Multilevel and Latent Variable Modeling with Composite Links and Exploded Likelihoods
ERIC Educational Resources Information Center
Rabe-Hesketh, Sophia; Skrondal, Anders
2007-01-01
Composite links and exploded likelihoods are powerful yet simple tools for specifying a wide range of latent variable models. Applications considered include survival or duration models, models for rankings, small area estimation with census information, models for ordinal responses, item response models with guessing, randomized response models,…
Hepatitis C virus recurrence after liver transplantation: a 10-year evaluation.
Gitto, Stefano; Belli, Luca Saverio; Vukotic, Ranka; Lorenzini, Stefania; Airoldi, Aldo; Cicero, Arrigo Francesco Giuseppe; Vangeli, Marcello; Brodosi, Lucia; Panno, Arianna Martello; Di Donato, Roberto; Cescon, Matteo; Grazi, Gian Luca; De Carlis, Luciano; Pinna, Antonio Daniele; Bernardi, Mauro; Andreone, Pietro
2015-04-07
To evaluate the predictors of 10-year survival of patients with hepatitis C recurrence. Data from 358 patients transplanted between 1989 and 2010 in two Italian transplant centers and with evidence of hepatitis C recurrence were analyzed. A χ(2), Fisher's exact test and Kruskal Wallis' test were used for categorical and continuous variables, respectively. Survival analysis was performed at 10 years after transplant using the Kaplan-Meier method, and a log-rank test was used to compare groups. A P level less than 0.05 was considered significant for all tests. Multivariate analysis of the predictive role of different variables on 10-year survival was performed by a stepwise Cox logistic regression. The ten-year survival of the entire population was 61.2%. Five groups of patients were identified according to the virological response or lack of a response to antiviral treatment and, among those who were not treated, according to the clinical status (mild hepatitis C recurrence, "too sick to be treated" and patients with comorbidities contraindicating the treatment). While the 10-year survival of treated and untreated patients was not different (59.1% vs 64.7%, P = 0.192), patients with a sustained virological response had a higher 10-year survival rate than both the "non-responders" (84.7% vs 39.8%, P < 0.0001) and too sick to be treated (84.7% vs 0%, P < 0.0001). Sustained virological responders had a survival rate comparable to patients untreated with mild recurrence (84.7% vs 89.3%). A sustained virological response and young donor age were independent predictors of 10-year survival. Sustained virological response significantly increased long-term survival. Awaiting the interferon-free regimen global availability, antiviral treatment might be questionable in selected subjects with mild hepatitis C recurrence.
NASA Astrophysics Data System (ADS)
Solimun
2017-05-01
The aim of this research is to model survival data from kidney-transplant patients using the partial least squares (PLS)-Cox regression, which can both meet and not meet the no-multicollinearity assumption. The secondary data were obtained from research entitled "Factors affecting the survival of kidney-transplant patients". The research subjects comprised 250 patients. The predictor variables consisted of: age (X1), sex (X2); two categories, prior hemodialysis duration (X3), diabetes (X4); two categories, prior transplantation number (X5), number of blood transfusions (X6), discrepancy score (X7), use of antilymphocyte globulin(ALG) (X8); two categories, while the response variable was patient survival time (in months). Partial least squares regression is a model that connects the predictor variables X and the response variable y and it initially aims to determine the relationship between them. Results of the above analyses suggest that the survival of kidney transplant recipients ranged from 0 to 55 months, with 62% of the patients surviving until they received treatment that lasted for 55 months. The PLS-Cox regression analysis results revealed that patients' age and the use of ALG significantly affected the survival time of patients. The factor of patients' age (X1) in the PLS-Cox regression model merely affected the failure probability by 1.201. This indicates that the probability of dying for elderly patients with a kidney transplant is 1.152 times higher than that for younger patients.
Vukmir, Rade B
2004-03-01
There are many variables that can have an effect on survival in cardiopulmonary arrest. This study examined the effect of urban, suburban, or rural location on the outcome of prehospital cardiac arrest as a secondary end point in a study evaluating the effect of bicarbonate on survival. The proportion of survivors within a type of EMS provider system as well as response times were compared. This prospective, randomized, double-blind clinical intervention trial enrolled 874 prehospital cardiopulmonary arrest patients encountered by prehospital urban, suburban, and rural regional EMS area. Population density (patients per square mile) calculation allowed classification into urban (>2000/mi2), suburban (>400/mi2), and rural (0-399/mi2) systems. This group underwent standard advanced cardiac life support (ACLS) intervention with or without early empiric administration of bicarbonate in a 1-mEq/kg dose. A group of demographic, diagnostic, and therapeutic variables were analyzed for their effect on survival. Times were measured from collapse until onset of medical intervention and survival measured as the presence of ED vital signs on arrival. Data analysis used chi-squared with Pearson correlation for survivorship and Student t test comparisons for response times. The overall survival rate was approximately 13.9% (110 of 793), ranging from 9% rural, 14% for suburban, and 23% for urban sites for 372 patients (P=.007). Survival differences were associated with classification of arrest locale in this sample-best for urban, suburban, followed by rural sites. There was no difference in time to bystander cardiopulmonary resuscitation, but medical response time (basic life support) was decreased for suburban or urban sites, and intervention (ACLS) and transport times were decreased for suburban sites alone. Although response times were differentiated by location, they were not necessarily predictive of survival. Factors other than response time such as patient population or resuscitation skill could influence survival from cardiac arrest occurring in diverse prehospital service areas.
Outbreeding increases offspring survival in wild greater horseshoe bats (Rhinolophus ferrumequinum).
Rossiter, S. J.; Jones, G.; Ransome, R. D.; Barratt, E. M.
2001-01-01
The factors influencing the survival of greater horseshoe bat (Rhinolophus ferrumequinum) offspring born over seven years at a maternity colony in south-west Britain were studied. The effects of a range of phenotypic and maternal variables were analysed using a historical data set. In addition, the influence of two genetic measures on mortality, individual heterozygosity and a new measure of outbreeding, termed mean d(2), was assessed. Logistic regressions were undertaken with survival modelled as a binary response variable. Survival to two life stages was studied for each variable and all models were developed for both sexes separately and together. Only one variable, mean d(2), was significantly associated with survival. Male offspring with high mean d(2) scores were more likely to survive to their first and second summers. The influence of mean d(2) was not due to a single locus under selection but a wider multilocus effect and probably represents heterosis as opposed to solely inbreeding depression. Therefore, the extent to which an individual is outbred may determine survival more than widely used phenotypic characteristics such as size and mass. Mean d(2) may reflect immunocompetence, which influences mortality. Protection of mating sites in order to facilitate gene flow and, therefore, outbreeding may help to promote population stability and growth. PMID:11375090
Schmutz, Joel A.; Thomson, David L.; Cooch, Evan G.; Conroy, Michael J.
2009-01-01
Stochastic variation in survival rates is expected to decrease long-term population growth rates. This expectation influences both life-history theory and the conservation of species. From this expectation, Pfister (1998) developed the important life-history prediction that natural selection will have minimized variability in those elements of the annual life cycle (such as adult survival rate) with high sensitivity. This prediction has not been rigorously evaluated for bird populations, in part due to statistical difficulties related to variance estimation. I here overcome these difficulties, and in an analysis of 62 populations, I confirm her prediction by showing a negative relationship between the proportional sensitivity (elasticity) of adult survival and the proportional variance (CV) of adult survival. However, several species deviated significantly from this expectation, with more process variance in survival than predicted. For instance, projecting the magnitude of process variance in annual survival for American redstarts (Setophaga ruticilla) for 25 years resulted in a 44% decline in abundance without assuming any change in mean survival rate. For most of these species with high process variance, recent changes in harvest, habitats, or changes in climate patterns are the likely sources of environmental variability causing this variability in survival. Because of climate change, environmental variability is increasing on regional and global scales, which is expected to increase stochasticity in vital rates of species. Increased stochasticity in survival will depress population growth rates, and this result will magnify the conservation challenges we face.
Fonseca, E; Cruz, J J; Dueñas, A; Gómez, A; Sánchez, P; Martín, G; Nieto, A; Soria, P; Muñoz, A; Gómez, J L; Pardal, J L
1996-01-01
Neoadjuvant chemotherapy for head and neck carcinoma is still an important treatment modality. The prognostic value of patient and tumor parameters has been extensively evaluated in several trials, yielding mixed results. We report the prognostic factors emerging from a group of patients undergoing neoadjuvant chemotherapy. From April 1986 to June 1992, 149 consecutive patients received cisplatin-5-fluorouracil-based neoadjuvant chemotherapy. After four courses of chemotherapy, patients underwent local-regional treatment with surgery, radiation or both. A variety of patient and tumor characteristics were evaluated as predictors for response to chemotherapy and survival. The complete response, partial response and no response rates to NAC were 52%, 33% and 15%, respectively. No parameters predicted response to chemotherapy. At a maximum follow-up of 87 months, overall survival was 39% and disease-free survival was 49%. Variables shown to be predictors of survival in univariate analyses were age, performance status, histology, site, T, N, stage, and response to chemotherapy. Using the Cox regression analysis, only complete response to induction chemotherapy (P = 0.0006), performance status (P = 0.03), stage (P = 0.01), age (P = 0.03) and primary tumor site (P = 0.04) emerged as independent prognostic factors for survival. Complete response to chemotherapy was confirmed as the strongest prognostic factor influencing survival. However, conventional clinicopathologic factors did not predict response, hence, potential prognostic biologic and molecular factors for response must be sought. At present, much effort must be made for the improvement of the complete response rate, which seems to be a requisite to prolong survival.
Toxicity Relationship Analysis Program (TRAP) Version 1.21
The Toxicity Relationship Analysis Program (TRAP) fits a sigmoidal toxic response versus exposure variable relationship to standard toxicity test data. It will analyze binary (e.g., survival) or continuous (e.g., growth, reproduction) biological effect variables as a function o...
Sananes, Nicolas; Rodo, Carlota; Peiro, Jose Luis; Britto, Ingrid Schwach Werneck; Sangi-Haghpeykar, Haleh; Favre, Romain; Joal, Arnaud; Gaudineau, Adrien; Silva, Marcos Marques da; Tannuri, Uenis; Zugaib, Marcelo; Carreras, Elena; Ruano, Rodrigo
2016-09-01
To evaluate the independent association of fetal pulmonary response and prematurity to postnatal outcomes after fetal tracheal occlusion for congenital diaphragmatic hernia. Fetal pulmonary response, prematurity (<37 weeks at delivery) and extreme prematurity (<32 weeks at delivery) were evaluated and compared between survivors and non-survivors at 6 months of life. Multivariable analysis was conducted with generalized linear mixed models for variables significantly associated with survival in univariate analysis. Eighty-four infants were included, of whom 40 survived (47.6%) and 44 died (52.4%). Univariate analysis demonstrated that survival was associated with greater lung response (p=0.006), and the absence of extreme preterm delivery (p=0.044). In multivariable analysis, greater pulmonary response after FETO was an independent predictor of survival (aOR 1.87, 95% CI 1.08-3.33, p=0.023), whereas the presence of extreme prematurity was not statistically associated with mortality after controlling for fetal pulmonary response (aOR 0.52, 95% CI 0.12-2.30, p=0.367). Fetal pulmonary response after FETO is the most important factor associated with survival, independently from the gestational age at delivery.
Uriarte, María; Muscarella, Robert; Zimmerman, Jess K
2018-02-01
Predicting the fate of tropical forests under a changing climate requires understanding species responses to climatic variability and extremes. Seedlings may be particularly vulnerable to climatic stress given low stored resources and undeveloped roots; they also portend the potential effects of climate change on future forest composition. Here we use data for ca. 50,000 tropical seedlings representing 25 woody species to assess (i) the effects of interannual variation in rainfall and solar radiation between 2007 and 2016 on seedling survival over 9 years in a subtropical forest; and (ii) how spatial heterogeneity in three environmental factors-soil moisture, understory light, and conspecific neighborhood density-modulate these responses. Community-wide seedling survival was not sensitive to interannual rainfall variability but interspecific variation in these responses was large, overwhelming the average community response. In contrast, community-wide responses to solar radiation were predominantly positive. Spatial heterogeneity in soil moisture and conspecific density were the predominant and most consistent drivers of seedling survival, with the majority of species exhibiting greater survival at low conspecific densities and positive or nonlinear responses to soil moisture. This environmental heterogeneity modulated impacts of rainfall and solar radiation. Negative conspecific effects were amplified during rainy years and at dry sites, whereas the positive effects of radiation on survival were more pronounced for seedlings existing at high understory light levels. These results demonstrate that environmental heterogeneity is not only the main driver of seedling survival in this forest but also plays a central role in buffering or exacerbating impacts of climate fluctuations on forest regeneration. Since seedlings represent a key bottleneck in the demographic cycle of trees, efforts to predict the long-term effects of a changing climate on tropical forests must take into account this environmental heterogeneity and how its effects on regeneration dynamics play out in long-term stand dynamics. © 2017 John Wiley & Sons Ltd.
Price, Melanie A; Butow, Phyllis N; Bell, Melanie L; deFazio, Anna; Friedlander, Michael; Fardell, Joanna E; Protani, Melinda M; Webb, Penelope M
2016-06-01
Women with advanced ovarian cancer generally have a poor prognosis but there is significant variability in survival despite similar disease characteristics and treatment regimens. The aim of this study was to determine whether psychosocial factors predict survival in women with ovarian cancer, controlling for potential confounders. The sample comprised 798 women with invasive ovarian cancer recruited into the Australian Ovarian Cancer Study and a subsequent quality of life study. Validated measures of depression, optimism, minimization, helplessness/hopelessness, and social support were completed 3-6 monthly for up to 2 years. Four hundred nineteen women (52.5 %) died over the follow-up period. Associations between time-varying psychosocial variables and survival were tested using adjusted Cox proportional hazard models. There was a significant interaction of psychosocial variables measured prior to first progression and overall survival, with higher optimism (adjusted hazard ratio per 1 standard deviation (HR) = 0.80, 95 % confidence interval (CI) 0.65-0.97), higher minimization (HR = 0.79, CI 0.66-0.94), and lower helplessness/hopelessness (HR = 1.40, CI 1.15-1.71) associated with longer survival. After disease progression, these variables were not associated with survival (optimism HR = 1.10, CI 0.95-1.27; minimization HR = 1.12, CI 0.95-1.31; and helplessness/hopelessness HR = 0.86, CI 0.74-1.00). Depression and social support were not associated with survival. In women with invasive ovarian cancer, psychosocial variables prior to disease progression appear to impact on overall survival, suggesting a preventive rather than modifying role. Addressing psychosocial responses to cancer and their potential impact on treatment decision-making early in the disease trajectory may benefit survival and quality of life.
Pre-disposition and epigenetics govern variation in bacterial survival upon stress.
Ni, Ming; Decrulle, Antoine L; Fontaine, Fanette; Demarez, Alice; Taddei, Francois; Lindner, Ariel B
2012-01-01
Bacteria suffer various stresses in their unpredictable environment. In response, clonal populations may exhibit cell-to-cell variation, hypothetically to maximize their survival. The origins, propagation, and consequences of this variability remain poorly understood. Variability persists through cell division events, yet detailed lineage information for individual stress-response phenotypes is scarce. This work combines time-lapse microscopy and microfluidics to uniformly manipulate the environmental changes experienced by clonal bacteria. We quantify the growth rates and RpoH-driven heat-shock responses of individual Escherichia coli within their lineage context, stressed by low streptomycin concentrations. We observe an increased variation in phenotypes, as different as survival from death, that can be traced to asymmetric division events occurring prior to stress induction. Epigenetic inheritance contributes to the propagation of the observed phenotypic variation, resulting in three-fold increase of the RpoH-driven expression autocorrelation time following stress induction. We propose that the increased permeability of streptomycin-stressed cells serves as a positive feedback loop underlying this epigenetic effect. Our results suggest that stochasticity, pre-disposition, and epigenetic effects are at the source of stress-induced variability. Unlike in a bet-hedging strategy, we observe that cells with a higher investment in maintenance, measured as the basal RpoH transcriptional activity prior to antibiotic treatment, are more likely to give rise to stressed, frail progeny.
Evidence of population resistance to extreme low flows in a fluvial-dependent fish species
Katz, Rachel A.; Freeman, Mary C.
2015-01-01
Extreme low streamflows are natural disturbances to aquatic populations. Species in naturally intermittent streams display adaptations that enhance persistence during extreme events; however, the fate of populations in perennial streams during unprecedented low-flow periods is not well-understood. Biota requiring swift-flowing habitats may be especially vulnerable to flow reductions. We estimated the abundance and local survival of a native fluvial-dependent fish species (Etheostoma inscriptum) across 5 years encompassing historic low flows in a sixth-order southeastern USA perennial river. Based on capturemark-recapture data, the study shoal may have acted as a refuge during severe drought, with increased young-of-the-year (YOY) recruitment and occasionally high adult immigration. Contrary to expectations, summer and autumn survival rates (30 days) were not strongly depressed during low-flow periods, despite 25%-80% reductions in monthly discharge. Instead, YOY survival increased with lower minimum discharge and in response to small rain events that increased low-flow variability. Age-1+ fish showed the opposite pattern, with survival decreasing in response to increasing low-flow variability. Results from this population dynamics study of a small fish in a perennial river suggest that fluvial-dependent species can be resistant to extreme flow reductions through enhanced YOY recruitment and high survival
Hydrothermal assessment of temporal variability in seedbed microclimate
Stuart P. Hardegree; Corey A. Moffet; Gerald N. Flerchinger; Jaepil Cho; Bruce A. Roundy; Thomas A. Jones; Jeremy J. James; Patrick E. Clark; Frederick B. Pierson
2013-01-01
The microclimatic requirements for successful seedling establishment are much more restrictive than those required for adult plant survival. The purpose of the current study was to use hydrothermal germination models and a soil energy and water flux model to evaluate intra- and interannual variability in seedbed microclimate relative to potential germination response...
Modulating cell-to-cell variability and sensitivity to death ligands by co-drugging
NASA Astrophysics Data System (ADS)
Flusberg, Deborah A.; Sorger, Peter K.
2013-06-01
TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) holds promise as an anti-cancer therapeutic but efficiently induces apoptosis in only a subset of tumor cell lines. Moreover, even in clonal populations of responsive lines, only a fraction of cells dies in response to TRAIL and individual cells exhibit cell-to-cell variability in the timing of cell death. Fractional killing in these cell populations appears to arise not from genetic differences among cells but rather from differences in gene expression states, fluctuations in protein levels and the extent to which TRAIL-induced death or survival pathways become activated. In this study, we ask how cell-to-cell variability manifests in cell types with different sensitivities to TRAIL, as well as how it changes when cells are exposed to combinations of drugs. We show that individual cells that survive treatment with TRAIL can regenerate the sensitivity and death-time distribution of the parental population, demonstrating that fractional killing is a stable property of cell populations. We also show that cell-to-cell variability in the timing and probability of apoptosis in response to treatment can be tuned using combinations of drugs that together increase apoptotic sensitivity compared to treatment with one drug alone. In the case of TRAIL, modulation of cell-to-cell variability by co-drugging appears to involve a reduction in the threshold for mitochondrial outer membrane permeabilization.
ERIC Educational Resources Information Center
Linn, Bernard S.; Linn, Margaret W.
1981-01-01
Studied (N=120) terminally ill cancer patients over several months on quality of life variables, functional status and survival. Counseled patients changed significantly more than controls by three months. Overall, response to counseling was similar in young and old patients, with both improving. (Author/JAC)
Brabeck, Kalina M; Guzmán, Michele R
2009-01-01
Women's responses to partner abuse are shaped by their particular sociocultural contexts. In this study, quantitative data were collected from 75 Mexican-origin women who survived intimate partner abuse, to identify variables associated with help-seeking to survive relationship abuse. Help-seeking was defined as use of formal (e.g., shelter) and informal (e.g., family) sources. Variables included two cultural variables: machismo (i.e., adherence to traditional gender roles) and familismo (i.e., valuing family cohesion and reciprocity), and four sociostructural variables: income, education, English proficiency, and immigrant status. Results indicated participants with higher levels of familismo sought informal help more frequently than those with lower levels. Women with grade school education, no English proficiency, and undocumented status sought formal help less frequently than those not constrained by these barriers.
β-Blocker pharmacogenetics in heart failure
Shin, Jaekyu
2009-01-01
β-Blockers (metoprolol, bisoprolol, and carvedilol) are a cornerstone of heart failure (HF) treatment. However, it is well recognized that responses to a β-blocker are variable among patients with HF. Numerous studies now suggest that genetic polymorphisms may contribute to variability in responses to a β-blocker, including left ventricular ejection fraction improvement, survival, and hospitalization due to HF exacerbation. This review summarizes the pharmacogenetic data for β-blockers in patients with HF and discusses the potential implications of β-blocker pharmacogenetics for HF patients. PMID:18437562
NASA Astrophysics Data System (ADS)
Botsford, L. W.; Moloney, C. L.; Hastings, A.; Largier, J. L.; Powell, T. M.; Higgins, K.; Quinn, J. F.
We synthesize the results of several modelling studies that address the influence of variability in larval transport and survival on the dynamics of marine metapopulations distributed along a coast. Two important benthic invertebrates in the California Current System (CCS), the Dungeness crab and the red sea urchin, are used as examples of the way in which physical oceanographic conditions can influence stability, synchrony and persistence of meroplanktonic metapopulations. We first explore population dynamics of subpopulations and metapopulations. Even without environmental forcing, isolated local subpopulations with density-dependence can vary on time scales roughly twice the generation time at high adult survival, shifting to annual time scales at low survivals. The high frequency behavior is not seen in models of the Dungeness crab, because of their high adult survival rates. Metapopulations with density-dependent recruitment and deterministic larval dispersal fluctuate in an asynchronous fashion. Along the coast, abundance varies on spatial scales which increase with dispersal distance. Coastwide, synchronous, random environmental variability tends to synchronize these metapopulations. Climate change could cause a long-term increase or decrease in mean larval survival, which in this model leads to greater synchrony or extinction respectively. Spatially managed metapopulations of red sea urchins go extinct when distances between harvest refugia become greater than the scale of larval dispersal. All assessments of population dynamics indicate that metapopulation behavior in general dependes critically on the temporal and spatial nature of larval dispersal, which is largely determined by physical oceanographic conditions. We therfore explore physical influences on larval dispersal patterns. Observed trends in temperature and salinity applied to laboratory-determined responses indicate that natural variability in temperature and salinity can lead to variability in larval development period on interannual (50%), intra-annual (20%) and latitudinal (200%) scales. Variability in development period significantly influences larval survival and, thus, net transport. Larval drifters that undertake diel vertical migration in a primitive equation model of coastal circulation (SPEM) demonstrate the importance of vertical migration in determining horizontal transport. Empirically derived estimates of the effects of wind forcing on larval transport of vertically migrating larvae (wind drift when near the surface and Ekman transport below the surface) match cross-shelf distributions in 4 years of existing larval data. We use a one-dimensional advection-diffusion model, which includes intra-annual timing of cross-shelf flows in the CCS, to explore the combined effects on settlement: (1) temperature- and salinity-dependent development and survival rates and (2) possible horizontal transport due to vertical migration of crab larvae. Natural variability in temperature, wind forcing, and the timing of the spring transition can cause the observed variability in recruitment. We conclude that understanding the dynamics of coastally distributed metapopulations in response to physically-induced variability in larval dispersal will be a critical step in assessing the effects of climate change on marine populations.
Li, X; Li, B; Xing, G; Meng, L
2017-02-01
To extrapolate the influence of plant cultivars varying in resistance levels to hosts on parasitoid life history traits, we estimated variation in parasitoid developmental and reproductive performances as a function of resistance in soybean cultivars, which were randomly chosen from a line of resistant genotypes. Our study showed that the parasitoid Meteorus pulchricornis varied widely in offspring survival and lifetime fecundity, but varied slightly in development time and adult body size, in response to the soybean cultivars that varied in resistance to the host Spodoptera litura. Furthermore, the variability in survival and lifetime fecundity was different between attacking the 2nd and the 4th instar host larvae, varying more in survival but less in lifetime fecundity when attacking the 4th than 2nd instar larvae. Our study provides further evidence supporting that plant resistance to herbivorous hosts have variable effects on different life history traits of higher trophic level parasitoids.
San Miguel, Jesus F.; Weisel, Katja C.; Song, Kevin W.; Delforge, Michel; Karlin, Lionel; Goldschmidt, Hartmut; Moreau, Philippe; Banos, Anne; Oriol, Albert; Garderet, Laurent; Cavo, Michele; Ivanova, Valentina; Alegre, Adrian; Martinez-Lopez, Joaquin; Chen, Christine; Renner, Christoph; Bahlis, Nizar Jacques; Yu, Xin; Teasdale, Terri; Sternas, Lars; Jacques, Christian; Zaki, Mohamed H.; Dimopoulos, Meletios A.
2015-01-01
Pomalidomide is a distinct oral IMiD® immunomodulatory agent with direct antimyeloma, stromal-support inhibitory, and immunomodulatory effects. The pivotal, multicenter, open-label, randomized phase 3 trial MM-003 compared pomalidomide + low-dose dexamethasone vs high-dose dexamethasone in 455 patients with refractory or relapsed and refractory multiple myeloma after failure of bortezomib and lenalidomide treatment. Initial results demonstrated significantly longer progression-free survival and overall survival with an acceptable tolerability profile for pomalidomide + low-dose dexamethasone vs high-dose dexamethasone. This secondary analysis describes patient outcomes by treatment history and depth of response. Pomalidomide + low-dose dexamethasone significantly prolonged progression-free survival and favored overall survival vs high-dose dexamethasone for all subgroups analyzed, regardless of prior treatments or refractory status. Both univariate and multivariate analyses showed that no variable relating to either the number (≤ or > 3) or type of prior treatment was a significant predictor of progression-free survival or overall survival. No cross-resistance with prior lenalidomide or thalidomide treatment was observed. Patients achieving a minimal response or better to pomalidomide + low-dose dexamethasone treatment experienced a survival benefit, which was even higher in those achieving at least a partial response (17.2 and 19.9 months, respectively, as compared with 7.5 months for patients with less than minimal response). These data suggest that pomalidomide + low-dose dexamethasone should be considered a standard of care in patients with refractory or relapsed and refractory multiple myeloma regardless of prior treatment. ClinicalTrials.gov: NCT01311687; EudraCT: 2010-019820-30. PMID:26160879
Modelling survival: exposure pattern, species sensitivity and uncertainty.
Ashauer, Roman; Albert, Carlo; Augustine, Starrlight; Cedergreen, Nina; Charles, Sandrine; Ducrot, Virginie; Focks, Andreas; Gabsi, Faten; Gergs, André; Goussen, Benoit; Jager, Tjalling; Kramer, Nynke I; Nyman, Anna-Maija; Poulsen, Veronique; Reichenberger, Stefan; Schäfer, Ralf B; Van den Brink, Paul J; Veltman, Karin; Vogel, Sören; Zimmer, Elke I; Preuss, Thomas G
2016-07-06
The General Unified Threshold model for Survival (GUTS) integrates previously published toxicokinetic-toxicodynamic models and estimates survival with explicitly defined assumptions. Importantly, GUTS accounts for time-variable exposure to the stressor. We performed three studies to test the ability of GUTS to predict survival of aquatic organisms across different pesticide exposure patterns, time scales and species. Firstly, using synthetic data, we identified experimental data requirements which allow for the estimation of all parameters of the GUTS proper model. Secondly, we assessed how well GUTS, calibrated with short-term survival data of Gammarus pulex exposed to four pesticides, can forecast effects of longer-term pulsed exposures. Thirdly, we tested the ability of GUTS to estimate 14-day median effect concentrations of malathion for a range of species and use these estimates to build species sensitivity distributions for different exposure patterns. We find that GUTS adequately predicts survival across exposure patterns that vary over time. When toxicity is assessed for time-variable concentrations species may differ in their responses depending on the exposure profile. This can result in different species sensitivity rankings and safe levels. The interplay of exposure pattern and species sensitivity deserves systematic investigation in order to better understand how organisms respond to stress, including humans.
Modelling survival: exposure pattern, species sensitivity and uncertainty
NASA Astrophysics Data System (ADS)
Ashauer, Roman; Albert, Carlo; Augustine, Starrlight; Cedergreen, Nina; Charles, Sandrine; Ducrot, Virginie; Focks, Andreas; Gabsi, Faten; Gergs, André; Goussen, Benoit; Jager, Tjalling; Kramer, Nynke I.; Nyman, Anna-Maija; Poulsen, Veronique; Reichenberger, Stefan; Schäfer, Ralf B.; van den Brink, Paul J.; Veltman, Karin; Vogel, Sören; Zimmer, Elke I.; Preuss, Thomas G.
2016-07-01
The General Unified Threshold model for Survival (GUTS) integrates previously published toxicokinetic-toxicodynamic models and estimates survival with explicitly defined assumptions. Importantly, GUTS accounts for time-variable exposure to the stressor. We performed three studies to test the ability of GUTS to predict survival of aquatic organisms across different pesticide exposure patterns, time scales and species. Firstly, using synthetic data, we identified experimental data requirements which allow for the estimation of all parameters of the GUTS proper model. Secondly, we assessed how well GUTS, calibrated with short-term survival data of Gammarus pulex exposed to four pesticides, can forecast effects of longer-term pulsed exposures. Thirdly, we tested the ability of GUTS to estimate 14-day median effect concentrations of malathion for a range of species and use these estimates to build species sensitivity distributions for different exposure patterns. We find that GUTS adequately predicts survival across exposure patterns that vary over time. When toxicity is assessed for time-variable concentrations species may differ in their responses depending on the exposure profile. This can result in different species sensitivity rankings and safe levels. The interplay of exposure pattern and species sensitivity deserves systematic investigation in order to better understand how organisms respond to stress, including humans.
Fitting Cure Rate Model to Breast Cancer Data of Cancer Research Center.
Baghestani, Ahmad Reza; Zayeri, Farid; Akbari, Mohammad Esmaeil; Shojaee, Leyla; Khadembashi, Naghmeh; Shahmirzalou, Parviz
2015-01-01
The Cox PH model is one of the most significant statistical models in studying survival of patients. But, in the case of patients with long-term survival, it may not be the most appropriate. In such cases, a cure rate model seems more suitable. The purpose of this study was to determine clinical factors associated with cure rate of patients with breast cancer. In order to find factors affecting cure rate (response), a non-mixed cure rate model with negative binomial distribution for latent variable was used. Variables selected were recurrence cancer, status for HER2, estrogen receptor (ER) and progesterone receptor (PR), size of tumor, grade of cancer, stage of cancer, type of surgery, age at the diagnosis time and number of removed positive lymph nodes. All analyses were performed using PROC MCMC processes in the SAS 9.2 program. The mean (SD) age of patients was equal to 48.9 (11.1) months. For these patients, 1, 5 and 10-year survival rates were 95, 79 and 50 percent respectively. All of the mentioned variables were effective in cure fraction. Kaplan-Meier curve showed cure model's use competence. Unlike other variables, existence of ER and PR positivity will increase probability of cure in patients. In the present study, Weibull distribution was used for the purpose of analysing survival times. Model fitness with other distributions such as log-N and log-logistic and other distributions for latent variable is recommended.
Peterson, Jennifer K.; Graham, Andrea L.; Dobson, Andrew P.; Chávez, Omar Triana
2015-01-01
The effect of a parasite on the life history of its vector is important for understanding and predicting disease transmission. Chagas disease agent Trypanosoma cruzi is a generalist parasite that is diverse across scales from its genetic diversity to the 100s of mammal and vector species it infects. Its vertebrate hosts show quite variable responses to infection, however, to date there are no studies looking at how T. cruzi variability might result in variable outcomes in its invertebrate host. Therefore, we investigated the effect of different T. cruzi I strains on Rhodnius prolixus survival and development. We found significant variation between insects infected with different strains, with some strains having no effect, as compared with uninfected insects, and others with significantly lower survival and development. We also found that different variables had varying importance between strains, with the effect of time postinfection and the blood:weight ratio of the infective meal significantly affecting the survival of insects infected with some strains, but not others. Our results suggest that T. cruzi can be pathogenic not only to its vertebrate hosts but also to its invertebrate hosts. PMID:26078316
Laws, Angela Nardoni; Belovsky, Gary E
2010-04-01
An important challenge facing ecologists is to understand how climate change may affect species performance and species interactions. However, predicting how changes in abiotic variables associated with climate change may affect species performance also depends on the biotic context, which can mediate species responses to climatic change. We conducted a 3-yr field experiment to determine how the herbivorous grasshopper Camnula pellucida (Scudder) responds to manipulations of temperature and population density. Grasshopper survival and fecundity decreased with density, indicating the importance of intraspecific competition. Female fecundity tended to increase with temperature, whereas grasshopper survival exhibited a unimodal response to temperature, with highest survival at intermediate temperatures. Grasshopper performance responses to temperature also depended on density. Peak survival in the low-density treatment occurred in warmer conditions than for the high-density treatment, indicating that the intensity of intraspecific competition varies with temperature. Our data show that changes to the temperature regimen can alter grasshopper performance and determine the intensity of intraspecific competition. However, the effects of temperature on grasshopper performance varied with density. Our data indicate the importance of the biotic context in mediating species responses to climatic factors associated with global change.
Lauren S. Urgenson; Charles B. Halpern; Paul D. Anderson
2013-01-01
We studied patterns of conifer regeneration over 12 years as part of a regional-scale experiment in variable-retention harvest in the Pacific Northwest, the DEMO Study. We compared survival and height growth of planted conifers and density and seral composition of natural regeneration among treatments with differing retention levels (15% versus 40%) and patterns (...
Lammert, Craig; Juran, Brian D.; Schlicht, Erik; Chan, Landon L.; Atkinson, Elizabeth J.; de Andrade, Mariza; Lazaridis, Konstantinos N.
2014-01-01
Background Biochemical response to Ursodeoxycholic Acid among patients with Primary Biliary Cirrhosis remains variable and there is no agreement of an ideal model. Novel assessment of response coupled to histologic progression was recently defined by the Toronto criteria. We retrospectively assessed transplant-free survival and clinical outcomes associated with Ursodeoxycholic Acid response to evaluate the Toronto criteria using a large North American cohort of PBC patients. Methods 398 PBC patients from the Mayo Clinic PBC Genetic Epidemiology (MCPGE) Registry were assessed for Ursodeoxycholic Acid treatment and biochemical response per the Toronto criteria. Responders were defined by reduction in alkaline phosphatase to less than or equal to 1.67 times the upper normal limit by 2 years of treatment, whereas non-responders had alkaline phosphatase values greater than 1.67 times the upper normal limit. Probability of survival was estimated using the Kaplan-Meier method. Results 302 (76%) patients were responders and 96 (24%) were non-responders. Significantly more non-responders developed adverse events related to chronic liver disease compared to responders (Hazard Ratio (HR): 2.77, P = 0.001). Biochemical responders and early-stage disease at treatment start was associated with improved overall transplant-free survival compared to non-responders (HR: 1.9) and patients with late stage disease (HR: 2.7) after age and sex adjustment. Conclusions The Toronto criteria are capable of identifying Ursodeoxycholic Acid-treated Primary Biliary Cirrhosis patients at risk of poor transplant-free survival and adverse clinical outcomes. Our data reveal that despite advanced disease at diagnosis, biochemical response per the Toronto criteria associates with improved overall transplant-free survival. PMID:24317935
Lammert, Craig; Juran, Brian D; Schlicht, Erik; Chan, Landon L; Atkinson, Elizabeth J; de Andrade, Mariza; Lazaridis, Konstantinos N
2014-10-01
Biochemical response to ursodeoxycholic acid among patients with primary biliary cirrhosis remains variable, and there is no agreement of an ideal model. Novel assessment of response coupled to histologic progression was recently defined by the Toronto criteria. We retrospectively assessed transplant-free survival and clinical outcomes associated with ursodeoxycholic acid response to evaluate the Toronto criteria using a large North American cohort of PBC patients. Three hundred and ninety-eight PBC patients from the Mayo Clinic PBC Genetic Epidemiology Registry were assessed for ursodeoxycholic acid treatment and biochemical response per the Toronto criteria. Responders were defined by reduction in alkaline phosphatase to less than or equal to 1.67 times the upper normal limit by 2 years of treatment, whereas non-responders had alkaline phosphatase values greater than 1.67 times the upper normal limit. Probability of survival was estimated using the Kaplan-Meier method. Three hundred and two (76 %) patients were responders and 96 (24 %) were non-responders. Significantly more non-responders developed adverse events related to chronic liver disease compared to responders (hazard ratio (HR) 2.77, P = 0.001). Biochemical responders and early-stage disease at treatment start was associated with improved overall transplant-free survival compared to non-responders (HR 1.9) and patients with late-stage disease (HR 2.7) after age and sex adjustment. The Toronto criteria are capable of identifying ursodeoxycholic acid-treated primary biliary cirrhosis patients at risk of poor transplant-free survival and adverse clinical outcomes. Our data reveal that despite advanced disease at diagnosis, biochemical response per the Toronto criteria associates with improved overall transplant-free survival.
Resistance is not futile: The response of hardwoods to fire-caused wounding
Elaine Kennedy Sutherland; Kevin Smith
2000-01-01
Fires wound trees; but not all of them, and not always. Specific fire behavior and differences among tree species and individual trees produce variable patterns of wounding and wound response. Our work focuses on the relationships between fire behavior and tree biology to better understand how hardwood trees resist injury to the lower stem and either survive or succumb...
Combining multiple sources of data to inform conservation of Lesser Prairie-Chicken populations
Ross, Beth; Haukos, David A.; Hagen, Christian A.; Pitman, James
2018-01-01
Conservation of small populations is often based on limited data from spatially and temporally restricted studies, resulting in management actions based on an incomplete assessment of the population drivers. If fluctuations in abundance are related to changes in weather, proper management is especially important, because extreme weather events could disproportionately affect population abundance. Conservation assessments, especially for vulnerable populations, are aided by a knowledge of how extreme events influence population status and trends. Although important for conservation efforts, data may be limited for small or vulnerable populations. Integrated population models maximize information from various sources of data to yield population estimates that fully incorporate uncertainty from multiple data sources while allowing for the explicit incorporation of environmental covariates of interest. Our goal was to assess the relative influence of population drivers for the Lesser Prairie-Chicken (Tympanuchus pallidicinctus) in the core of its range, western and southern Kansas, USA. We used data from roadside lek count surveys, nest monitoring surveys, and survival data from telemetry monitoring combined with climate (Palmer drought severity index) data in an integrated population model. Our results indicate that variability in population growth rate was most influenced by variability in juvenile survival. The Palmer drought severity index had no measurable direct effects on adult survival or mean number of offspring per female; however, there were declines in population growth rate following severe drought. Because declines in population growth rate occurred at a broad spatial scale, declines in response to drought were likely due to decreases in chick and juvenile survival rather than emigration outside of the study area. Overall, our model highlights the importance of accounting for environmental and demographic sources of variability, and provides a thorough method for simultaneously evaluating population demography in response to long-term climate effects.
Modelling survival: exposure pattern, species sensitivity and uncertainty
Ashauer, Roman; Albert, Carlo; Augustine, Starrlight; Cedergreen, Nina; Charles, Sandrine; Ducrot, Virginie; Focks, Andreas; Gabsi, Faten; Gergs, André; Goussen, Benoit; Jager, Tjalling; Kramer, Nynke I.; Nyman, Anna-Maija; Poulsen, Veronique; Reichenberger, Stefan; Schäfer, Ralf B.; Van den Brink, Paul J.; Veltman, Karin; Vogel, Sören; Zimmer, Elke I.; Preuss, Thomas G.
2016-01-01
The General Unified Threshold model for Survival (GUTS) integrates previously published toxicokinetic-toxicodynamic models and estimates survival with explicitly defined assumptions. Importantly, GUTS accounts for time-variable exposure to the stressor. We performed three studies to test the ability of GUTS to predict survival of aquatic organisms across different pesticide exposure patterns, time scales and species. Firstly, using synthetic data, we identified experimental data requirements which allow for the estimation of all parameters of the GUTS proper model. Secondly, we assessed how well GUTS, calibrated with short-term survival data of Gammarus pulex exposed to four pesticides, can forecast effects of longer-term pulsed exposures. Thirdly, we tested the ability of GUTS to estimate 14-day median effect concentrations of malathion for a range of species and use these estimates to build species sensitivity distributions for different exposure patterns. We find that GUTS adequately predicts survival across exposure patterns that vary over time. When toxicity is assessed for time-variable concentrations species may differ in their responses depending on the exposure profile. This can result in different species sensitivity rankings and safe levels. The interplay of exposure pattern and species sensitivity deserves systematic investigation in order to better understand how organisms respond to stress, including humans. PMID:27381500
Karadima, Maria L; Saetta, Angelica A; Chatziandreou, Ilenia; Lazaris, Andreas C; Patsouris, Efstratios; Tsavaris, Nikolaos
2016-10-01
Our aim was to evaluate the predictive and prognostic influence of BRAF mutation and other molecular, clinical and laboratory parameters in stage IV colorectal cancer (CRC). 60 patients were included in this retrospective analysis, and 17 variables were examined for their relation with treatment response and survival. KRAS mutation was identified in 40.3 % of cases, BRAF and PIK3CA in 8.8 % and 10.5 % respectively. 29.8 % of patients responded to treatment. Median survival time was 14.3 months. Weight loss, fever, abdominal metastases, blood transfusion, hypoalbuminaimia, BRAF and PIK3CA mutations, CRP and DNA Index were associated with survival. In multivariate analysis, male patients had 3.8 times higher probability of response, increased DNA Index was inversely correlated with response and one unit raise of DNA Index augmented 6 times the probability of death. Our findings potentiate the prognostic role of BRAF, PIK3CA mutations and ploidy in advanced CRC.
Brooks, Steven C; Schmicker, Robert H; Cheskes, Sheldon; Christenson, Jim; Craig, Alan; Daya, Mohamud; Kudenchuk, Peter J; Nichol, Graham; Zive, Dana; Morrison, Laurie J
2017-08-01
Some patients with out-of-hospital cardiac arrest (OHCA) assessed by emergency medical services (EMS) do not receive attempts at resuscitation on the basis of perceived futility. 1) To measure variability in the initiation of resuscitation attempts in EMS-assessed OHCA patients across EMS agencies, 2) to evaluate the association between selected EMS agency characteristics and the proportion of patients receiving resuscitation attempts, and 3) to evaluate the association between proportion receiving resuscitation attempts and survival. A retrospective cohort study using data from 129 EMS agencies participating in the Resuscitation Outcomes Consortium (ROC) epidemiologic registry (EPISTRY) - Cardiac Arrest from 12/01/2005 to 12/31/2010. We included non-traumatic OHCA patients assessed by EMS. We included 86,912 OHCA patients. Overall, 54.8% had resuscitation attempted by EMS providers, varying from 23.9% to 100% (p=<0.001) across EMS agencies. The proportion of patients receiving a resuscitation attempt was 7.87% less (95% CI 3.73-12.0) among agencies with longer average response intervals (≥6min) compared with shorter average response intervals (<6min) and 16.9% less (95% CI 11.9-21.9) among agencies with higher levels of advanced life support (ALS) availability (≥50% of available units) compared with lower levels of ALS availability (<50% of available units). There was a moderate positive correlation between the proportion of patients with resuscitation attempts and survival to hospital discharge (r=0.54, p<0.001). The proportion of patients with OHCA who receive resuscitation attempts is variable across EMS agencies and is associated with EMS response interval, ALS unit availability and geographic region. On average, survival was higher among EMS agencies more likely to initiate resuscitation. Copyright © 2017 Elsevier B.V. All rights reserved.
Cardiovascular response to dobutamine stress predicts outcome in severe sepsis and septic shock.
Kumar, Anand; Schupp, Elizabeth; Bunnell, Eugene; Ali, Amjad; Milcarek, Barry; Parrillo, Joseph E
2008-01-01
During septic shock, resistance to the haemodynamic effects of catecholamine vasopressors and inotropes is a well-recognised marker of mortality risk. However, the specific cardiovascular or metabolic response elements that are most closely associated with outcome have not been well defined. The objective of this study was to assess cardiovascular and metabolic responses to dobutamine as correlates of outcome in patients with severe sepsis or septic shock. A prospective, non-randomised, non-blinded interventional study of graded dobutamine challenge (0, 5, 10, and 15 mug/kg/min) in adult patients who had undergone pulmonary artery catheterisation within 48 hours of onset of severe sepsis or septic shock (8 survivors/15 non-survivors) was performed. Radionuclide cineangiography during graded infusion was used to determine biventricular ejection fractions at each increment of dobutamine. In univariate analysis, a variety of cardiovascular or haemodynamic and oxygen transport or metabolic variables (at the point of maximum cardiac index response for a given subject) were associated with survival including: increased stroke volume index (p = 0.0003); right ventricular end-diastolic volume index (p = 0.0047); left ventricular stroke work index (p = 0.0054); oxygen delivery index (p = 0.0084); cardiac index (p = 0.0093); systolic blood pressure/left ventricular end-systolic volume index ratio (p = 0.0188); left ventricular ejection fraction (p = 0.0160); venous oxygen content (p = 0.0208); mixed venous oxygen saturation (p = 0.0234); pulse pressure (p = 0.0403); decreased pulmonary artery diastolic pressure (p = 0.0133); systemic vascular resistance index (p = 0.0154); extraction ratio (p = 0.0160); and pulmonary vascular resistance index (p = 0.0390). Increases of stroke volume index of greater than or less than 8.5 mL/m2 were concordant with survival or death in 21 of 23 cases. Multivariate profile construction showed stroke volume index as the dominant discriminating variable for survival with the systolic blood pressure/left ventricular end-systolic volume index ratio alone among all other variables significantly improving the model. Survivors maintain cardiac responsiveness to catecholamine stimulation during septic shock. Survival from severe sepsis or septic shock is associated with increased cardiac performance and contractility indices during dobutamine infusion. Further studies are required to determine whether these parameters are predictive of outcome in a larger severe sepsis/septic shock population.
Lescroël, Amélie; Dugger, Katie M; Ballard, Grant; Ainley, David G
2009-07-01
1. Heterogeneity in individual quality (i.e. individuals having different performance levels that are consistent throughout life) can drive the demography of iteroparous species, but quality in the context of environmental variability has rarely been evaluated. 2. We investigated the demographic responses of a long-lived seabird, the Adélie penguin (Pygoscelis adeliae), to contrasting environmental conditions as a function of reproductive success, breeding quality (BQ) and experience. A continuous index of BQ (BQI) was developed to reflect an individual's ability, relative to others, to produce viable offspring. 3. First, we assessed the relative importance of costs of reproduction vs. heterogeneity in quality by comparing survival and reproductive probabilities among deferred, successful and unsuccessful breeders under 'demanding' conditions using multistate capture-mark-recapture modelling. Then, we quantified the influence of BQI on adult survival among experienced breeders vs. the whole study population under both 'normal' and 'demanding' conditions. 4. Higher survival rates were exhibited by successful (74-76%) compared to unsuccessful breeders (64%); the former also more frequently reproduced successfully at year t + 1. 5. From 1997 to 2006, adult survival ranged from 64-79%, with BQI accounting for 91% of variability in the entire study population, but only 17% in experienced breeders. The weakened relationship between BQI and survival in experienced breeders supports the theory that selection during the first reproductive event accounts for a more homogeneous pool of experienced breeders. 6. No significant effect of environmental covariates on survival was evident, suggesting that what appeared to be demanding conditions were within the range that could be buffered by this species. 7. For the first time in seabirds, a quadratic relationship between adult survival and BQI showed that adult survival is shaped by both heterogeneity in quality and reproductive costs. Our study confirms that population demographic patterns are affected by factors at the individuals' level (e.g., individual quality) that are obscured at population-scale levels.
Dose-Response Calculator for ArcGIS
Hanser, Steven E.; Aldridge, Cameron L.; Leu, Matthias; Nielsen, Scott E.
2011-01-01
The Dose-Response Calculator for ArcGIS is a tool that extends the Environmental Systems Research Institute (ESRI) ArcGIS 10 Desktop application to aid with the visualization of relationships between two raster GIS datasets. A dose-response curve is a line graph commonly used in medical research to examine the effects of different dosage rates of a drug or chemical (for example, carcinogen) on an outcome of interest (for example, cell mutations) (Russell and others, 1982). Dose-response curves have recently been used in ecological studies to examine the influence of an explanatory dose variable (for example, percentage of habitat cover, distance to disturbance) on a predicted response (for example, survival, probability of occurrence, abundance) (Aldridge and others, 2008). These dose curves have been created by calculating the predicted response value from a statistical model at different levels of the explanatory dose variable while holding values of other explanatory variables constant. Curves (plots) developed using the Dose-Response Calculator overcome the need to hold variables constant by using values extracted from the predicted response surface of a spatially explicit statistical model fit in a GIS, which include the variation of all explanatory variables, to visualize the univariate response to the dose variable. Application of the Dose-Response Calculator can be extended beyond the assessment of statistical model predictions and may be used to visualize the relationship between any two raster GIS datasets (see example in tool instructions). This tool generates tabular data for use in further exploration of dose-response relationships and a graph of the dose-response curve.
Reassessment of the relationship between M-protein decrement and survival in multiple myeloma.
Palmer, M; Belch, A; Hanson, J; Brox, L
1989-01-01
The relationship between percentage M-protein decrement and survival is assessed in 134 multiple myeloma patients. The correlation did not achieve statistical significance (P = 0.069). Multivariate analysis using the Cox proportional hazards model, including a number of previously recognised prognostic factors, showed only percentage M-protein decrement, creatinine and haemoglobin to be significantly correlated with survival. However, the R'-statistic for each of these variables was low, indicating that their prognostic power is weak. We conclude that neither the percentage M-protein decrement nor the response derived from it can be used as an accurate means of assessing the efficacy of treatment in myeloma. Mature survival data alone should be used for this purpose.
Reassessment of the relationship between M-protein decrement and survival in multiple myeloma.
Palmer, M.; Belch, A.; Hanson, J.; Brox, L.
1989-01-01
The relationship between percentage M-protein decrement and survival is assessed in 134 multiple myeloma patients. The correlation did not achieve statistical significance (P = 0.069). Multivariate analysis using the Cox proportional hazards model, including a number of previously recognised prognostic factors, showed only percentage M-protein decrement, creatinine and haemoglobin to be significantly correlated with survival. However, the R'-statistic for each of these variables was low, indicating that their prognostic power is weak. We conclude that neither the percentage M-protein decrement nor the response derived from it can be used as an accurate means of assessing the efficacy of treatment in myeloma. Mature survival data alone should be used for this purpose. PMID:2757916
Individual traits as determinants of time to death under extreme drought in Pinus sylvestris L.
Garcia-Forner, Núria; Sala, Anna; Biel, Carme; Savé, Robert; Martínez-Vilalta, Jordi
2016-10-01
Plants exhibit a variety of drought responses involving multiple interacting traits and processes, which makes predictions of drought survival challenging. Careful evaluation of responses within species, where individuals share broadly similar drought resistance strategies, can provide insight into the relative importance of different traits and processes. We subjected Pinus sylvestris L. saplings to extreme drought (no watering) leading to death in a greenhouse to (i) determine the relative effect of predisposing factors and responses to drought on survival time, (ii) identify and rank the importance of key predictors of time to death and (iii) compare individual characteristics of dead and surviving trees sampled concurrently. Time until death varied over 3 months among individual trees (from 29 to 147 days). Survival time was best predicted (higher explained variance and impact on the median survival time) by variables related to carbon uptake and carbon/water economy before and during drought. Trees with higher concentrations of monosaccharides before the beginning of the drought treatment and with higher assimilation rates prior to and during the treatment survived longer (median survival time increased 25-70 days), even at the expense of higher water loss. Dead trees exhibited less than half the amount of nonstructural carbohydrates (NSCs) in branches, stem and relative to surviving trees sampled concurrently. Overall, our results indicate that the maintenance of carbon assimilation to prevent acute depletion of NSC content above some critical level appears to be the main factor explaining survival time of P. sylvestris trees under extreme drought. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Adaptive and plastic responses of Quercus petraea populations to climate across Europe.
Sáenz-Romero, Cuauhtémoc; Lamy, Jean-Baptiste; Ducousso, Alexis; Musch, Brigitte; Ehrenmann, François; Delzon, Sylvain; Cavers, Stephen; Chałupka, Władysław; Dağdaş, Said; Hansen, Jon Kehlet; Lee, Steve J; Liesebach, Mirko; Rau, Hans-Martin; Psomas, Achilleas; Schneck, Volker; Steiner, Wilfried; Zimmermann, Niklaus E; Kremer, Antoine
2017-07-01
How temperate forests will respond to climate change is uncertain; projections range from severe decline to increased growth. We conducted field tests of sessile oak (Quercus petraea), a widespread keystone European forest tree species, including more than 150 000 trees sourced from 116 geographically diverse populations. The tests were planted on 23 field sites in six European countries, in order to expose them to a wide range of climates, including sites reflecting future warmer and drier climates. By assessing tree height and survival, our objectives were twofold: (i) to identify the source of differential population responses to climate (genetic differentiation due to past divergent climatic selection vs. plastic responses to ongoing climate change) and (ii) to explore which climatic variables (temperature or precipitation) trigger the population responses. Tree growth and survival were modeled for contemporary climate and then projected using data from four regional climate models for years 2071-2100, using two greenhouse gas concentration trajectory scenarios each. Overall, results indicated a moderate response of tree height and survival to climate variation, with changes in dryness (either annual or during the growing season) explaining the major part of the response. While, on average, populations exhibited local adaptation, there was significant clinal population differentiation for height growth with winter temperature at the site of origin. The most moderate climate model (HIRHAM5-EC; rcp4.5) predicted minor decreases in height and survival, while the most extreme model (CCLM4-GEM2-ES; rcp8.5) predicted large decreases in survival and growth for southern and southeastern edge populations (Hungary and Turkey). Other nonmarginal populations with continental climates were predicted to be severely and negatively affected (Bercé, France), while populations at the contemporary northern limit (colder and humid maritime regions; Denmark and Norway) will probably not show large changes in growth and survival in response to climate change. © 2017 John Wiley & Sons Ltd.
Herrero, M Lucrecia; Torres, Romina C; Renison, Daniel
2016-02-01
We asked whether prescribed fire could be a useful management tool to reduce invasion by non-native plants in an ecosystem where native plants are supposed to be adapted to fires. Specifically, we compare the post-fire resprouting response of native and non-native woody species in Chaco Serrano forest of central Argentina. The measurements were carried out in five burnt areas where we selected ten native and seven non-native species. Our response variables were (1) post-fire survival, (2) types of resprouts, and (3) the growth of the resprouts. Our main results show that one year after the fire, survivals of native and non-native species were 0.84 and 0.89, respectively, with variances in survival seven times smaller in the native species group. Type of resprout was also less variable in native species, while growth of the resprouts was similar in native and non-native groups. We interpret that in most cases, the burning a forest with mixed native and non-native plants through prescribed fires will not differentially stop the invasion by non-native woody species even in ecosystems which are presumed to be relatively resistant to fires such as our study area.
High and variable mortality of leatherback turtles reveal possible anthropogenic impacts.
Santidrián Tomillo, P; Robinson, N J; Sanz-Aguilar, A; Spotila, J R; Paladino, F V; Tavecchia, G
2017-08-01
The number of nesting leatherback turtles (Dermochelys coriacea) in the eastern Pacific Ocean has declined dramatically since the late 1980s. This decline has been attributed to egg poaching and interactions with fisheries. However, it is not clear how much of the decline should also be ascribed to variability in the physical characteristics of the ocean. We used data on individually marked turtles that nest at Playa Grande, Costa Rica, to address whether climatic variability affects survival and inter-breeding interval. Because some turtles might nest undetected, we used capture-recapture models to model survival probability accounting for a detection failure. In addition, as the probability of reproduction is constrained by past nesting events, we formulated a new parameterization to estimate inter-breeding intervals and contrast hypotheses on the role of climatic covariates on reproductive frequency. Average annual survival for the period 1993-2011 was low (0.78) and varied over time ranging from 0.49 to 0.99 with a negative temporal trend mainly due to the high mortality values registered after 2004. Survival probability was not associated with the Multivariate ENSO Index of the South Pacific Ocean (MEI) but this index explained 24% of the temporal variability in the reproductive frequency. The probability of a turtle to permanently leave after the first encounter was 26%. This high proportion of transients might be associated with a high mortality cost of the first reproduction or with a long-distance nesting dispersal after the first nesting season. Although current data do not allow separating these two hypotheses, low encounter rate at other locations and high investment in reproduction, supports the first hypothesis. The low and variable annual survival probability has largely contributed to the decline of this leatherback population. The lack of correlation between survival probability and the most important climatic driver of oceanic processes in the Pacific discards a climate-related decline and point to anthropogenic sources of mortality as the main causes responsible for the observed population decline. © 2017 by the Ecological Society of America.
Kowalczyk, Nicole D; Reina, Richard D; Preston, Tiana J; Chiaradia, André
2015-08-01
Marine animals forage in areas that aggregate prey to maximize their energy intake. However, these foraging 'hot spots' experience environmental variability, which can substantially alter prey availability. To survive and reproduce animals need to modify their foraging in response to these prey shifts. By monitoring their inter-annual foraging behaviours, we can understand which environmental variables affect their foraging efficiency, and can assess how they respond to environmental variability. Here, we monitored the foraging behaviour and isotopic niche of little penguins (Eudyptula minor), over 3 years (2008, 2011, and 2012) of climatic and prey variability within Port Phillip Bay, Australia. During drought (2008), penguins foraged in close proximity to the Yarra River outlet on a predominantly anchovy-based diet. In periods of heavy rainfall, when water depth in the largest tributary into the bay (Yarra River) was high, the total distance travelled, maximum distance travelled, distance to core-range, and size of core- and home-ranges of penguins increased significantly. This larger foraging range was associated with broad dietary diversity and high reproductive success. These results suggest the increased foraging range and dietary diversity of penguins were a means to maximize resource acquisition rather than a strategy to overcome local depletions in prey. Our results demonstrate the significance of the Yarra River in structuring predator-prey interactions in this enclosed bay, as well as the flexible foraging strategies of penguins in response to environmental variability. This plasticity is central to the survival of this small-ranging, resident seabird species.
NASA Astrophysics Data System (ADS)
Astuti Thamrin, Sri; Taufik, Irfan
2018-03-01
Dengue haemorrhagic fever (DHF) is an infectious disease caused by dengue virus. The increasing number of people with DHF disease correlates with the neighbourhood, for example sub-districts, and the characteristics of the sub-districts are formed from individuals who are domiciled in the sub-districts. Data containing individuals and sub-districts is a hierarchical data structure, called multilevel analysis. Frequently encountered response variable of the data is the time until an event occurs. Multilevel and spatial models are being increasingly used to obtain substantive information on area-level inequalities in DHF survival. Using a case study approach, we report on the implications of using multilevel with spatial survival models to study geographical inequalities in all cause survival.
Fariña-Sarasqueta, A; Gosens, M J E M; Moerland, E; van Lijnschoten, I; Lemmens, V E P P; Slooter, G D; Rutten, H J T; van den Brule, Adriaan J C
2011-08-01
Although the predictive and prognostic value of thymidylate synthase (TS) expression and gene polymorphism in colon cancer has been widely studied, the results are inconclusive probably because of methodological differences. With this study, we aimed to elucidate the role of TS gene polymorphisms genotyping in therapy response in stage III colon carcinoma patients treated with 5-FU adjuvant chemotherapy. 251 patients diagnosed with stage III colon carcinoma treated with surgery followed by 5-FU based adjuvant therapy were selected. The variable number of tandem repeats (VNTR) and the single nucleotide polymorphism (SNP) in the 5'untranslated region of the TS gene were genotyped. There was a positive association between tumor T stage and the VNTR genotypes (p = 0.05). In both univariate and multivariate survival analysis no effects of the studied polymorphisms on survival were found. However, there was an association between both polymorphisms and age. Among patients younger than 60 years, the patients homozygous for 2R seemed to have a better overall survival, whereas among the patients older than 67 this longer survival was seen by the carriers of other genotypes. We conclude that the TS VNTR and SNP do not predict response to 5-FU therapy in patients with stage III colon carcinoma. However, age appears to modify the effects of TS polymorphisms on survival.
Fariña-Sarasqueta, A; Gosens, M J E M; Moerland, E; van Lijnschoten, I; Lemmens, V E P P; Slooter, G D; Rutten, H J T; van den Brule, A J C
2010-01-01
Although the predictive and prognostic value of thymidylate synthase (TS) expression and gene polymorphism in colon cancer has been widely studied, the results are inconclusive probably because of methodological differences. With this study, we aimed to elucidate the role of TS gene polymorphisms genotyping in therapy response in stage III colon carcinoma patients treated with 5-FU adjuvant chemotherapy. 251 patients diagnosed with stage III colon carcinoma treated with surgery followed by 5-FU based adjuvant therapy were selected. The variable number of tandem repeats (VNTR) and the single nucleotide polymorphism (SNP) in the 5'-untranslated region of the TS gene were genotyped. There was a positive association between tumor T stage and the VNTR genotypes (p=0.05).In both univariate and multivariate survival analysis no effects of the studied polymorphisms on survival were found. However, there was an association between both polymorphisms and age. Among patients younger than 60 years, the patients homozygous for 2R seemed to have a better overall survival, whereas among the patients older than 67 this longer survival was seen by the carriers of other genotypes. We conclude that the TS VNTR and SNP do not predict response to 5-FU therapy in patients with stage III colon carcinoma. However, age appears to modify the effects of TS polymorphisms on survival.
Fariña-Sarasqueta, A.; Gosens, M. J. E. M.; Moerland, E.; van Lijnschoten, I.; Lemmens, V. E. P. P.; Slooter, G. D.; Rutten, H. J. T.; van den Brule, A. J. C.
2010-01-01
Aim: Although the predictive and prognostic value of thymidylate synthase (TS) expression and gene polymorphism in colon cancer has been widely studied, the results are inconclusive probably because of methodological differences. With this study, we aimed to elucidate the role of TS gene polymorphisms genotyping in therapy response in stage III colon carcinoma patients treated with 5-FU adjuvant chemotherapy. Patients and Methods: 251 patients diagnosed with stage III colon carcinoma treated with surgery followed by 5-FU based adjuvant therapy were selected. The variable number of tandem repeats (VNTR) and the single nucleotide polymorphism (SNP) in the 5′-untranslated region of the TS gene were genotyped. Results: There was a positive association between tumor T stage and the VNTR genotypes (p=0.05). In both univariate and multivariate survival analysis no effects of the studied polymorphisms on survival were found. However, there was an association between both polymorphisms and age. Among patients younger than 60 years, the patients homozygous for 2R seemed to have a better overall survival, whereas among the patients older than 67 this longer survival was seen by the carriers of other genotypes. Conclusion: We conclude that the TS VNTR and SNP do not predict response to 5-FU therapy in patients with stage III colon carcinoma. However, age appears to modify the effects of TS polymorphisms on survival. PMID:20966539
Doxorubicin chemotherapy for presumptive cardiac hemangiosarcoma in dogs†.
Mullin, C M; Arkans, M A; Sammarco, C D; Vail, D M; Britton, B M; Vickery, K R; Risbon, R E; Lachowicz, J; Burgess, K E; Manley, C A; Clifford, C A
2016-12-01
Sixty-four dogs were treated with single-agent doxorubicin (DOX) for presumptive cardiac hemangiosarcoma (cHSA). The objective response rate (CR + PR) was 41%, and the biologic response rate (CR + PR + SD), or clinical benefit, was 68%. The median progression-free survival (PFS) for treated dogs was 66 days. The median survival time (MST) for this group was 116 days and was significantly improved compared to a MST of 12 days for untreated control dogs (P = 0.0001). Biologic response was significantly associated with improved PFS (P < 0.0001) and OS (P < 0.0001). Univariate analysis identified larger tumour size as a variable negatively associated with PFS. The high rate of clinical benefit and improved MST suggest that DOX has activity in canine cHSA. © 2014 John Wiley & Sons Ltd.
Santo, A; Mattana, E; Frigau, L; Marzo Pastor, A; Picher Morelló, M C; Bacchetta, G
2017-05-01
Brassica insularis is a protected plant that grows on both coastal and inland cliffs in the western Mediterranean Basin. The objective of this study was to test if any variability exists in the salt stress response during seed germination and seedling development in this species relative to its provenance habitat. Variability among three populations in the salt stress effects on seed germination and recovery under different temperatures was evaluated. The effect of nebulisation of a salt solution on seedling development was evaluated between populations growing at different distances from the sea. Seeds of B. insularis could germinate at NaCl concentrations up to 200 mm. Seed viability was negatively affected by salt, and recovery ability decreased with increasing temperature or salinity. Inter-population variability was detected in salt response during the seed germination phase, as well as in seedling salt spray tolerance. The inland population seedlings had drastically decreased survival and life span and failed to survive to the end of the experiment. In contrast, at least 90% of the coastal seedlings survived, even when sprayed at the highest frequency with salt solution. This study allowed investigation of two natural factors, soil salinity and marine aerosols, widely present in the B. insularis habitat, and provided the first insights into ecology of this protected species and its distribution in the Mediterranean. These results might be useful in understanding the actual distributions of other species with the same ecology that experience these same abiotic parameters. © 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.
Immunostimulants in fish diets
Gannam, A.L.; Schrock, R.M.
1999-01-01
Various immunostimulants and their methods of application in fish culture are examined in this review. Important variables such as life stage and innate disease resistance of the fish; immunostimulant used, its structure and mode of action; and the fish's environment are discussed. Conflicting results have been published about the efficacy of immunostimulants in fish diets. Some researchers have had positive responses demonstrated as increased fish survival, others have not. Generally, immunostimulants enhance individual components of the non-specific immune response but that does not always translate into increased fish survival. In addition, immunostimulants fed at too high a dose or for too long can be immunosuppressive. [Article copies available for a fee from The Haworth Document Delivery Service: 1-800-342-9678. E-mail address: getinfo@haworthpressinc.com ].
Chomsky, D B; Lang, C C; Rayos, G H; Shyr, Y; Yeoh, T K; Pierson, R N; Davis, S F; Wilson, J R
1996-12-15
Peak exercise oxygen consumption (Vo2), a noninvasive index of peak exercise cardiac output (CO), is widely used to select candidates for heart transplantation. However, peak exercise Vo2 can be influenced by noncardiac factors such as deconditioning, motivation, or body composition and may yield misleading prognostic information. Direct measurement of the CO response to exercise may avoid this problem and more accurately predict prognosis. Hemodynamic and ventilatory responses to maximal treadmill exercise were measured in 185 ambulatory patients with chronic heart failure who had been referred for cardiac transplantation (mean left ventricular ejection fraction, 22 +/- 7%; mean peak Vo2, 12.9 +/- 3.0 mL. min-1.kg-1). CO response to exercise was normal in 83 patients and reduced in 102. By univariate analysis, patients with normal CO responses had a better 1-year survival rate (95%) than did those with reduced CO responses (72%) (P < .0001). Survival in patients with peak Vo2 of > 14 mL.min-1.kg-1 (88%) was not different from that of patients with peak Vo2 of < or = 14 mL.min-1.kg-1 (79%) (P = NS). However, survival was worse in patients with peak Vo2 of < or = 10 mL.min-1.kg-1 (52%) versus those with peak Vo2 of > 10 mL.min-1.kg-1 (89%) (P < .0001). By Cox regression analysis, exercise CO response was the strongest independent predictor of survival (risk ratio, 4.3), with peak Vo2 dichotomized at 10 mL. min-1.kg-1 (risk ratio, 3.3) as the only other independent predictor. Patients with reduced CO responses and peak Vo2 of < or = 10 mL.min-1.kg-1 had an extremely poor 1-year survival rate (38%). Both CO response to exercise and peak exercise Vo2 provide valuable independent prognostic information in ambulatory patients with heart failure. These variables should be used in combination to select potential heart transplantation candidates.
Charrieau, Laurie M; Filipsson, Helena L; Nagai, Yukiko; Kawada, Sachiko; Ljung, Karl; Kritzberg, Emma; Toyofuku, Takashi
2018-07-01
Coastal areas display natural large environmental variability such as frequent changes in salinity, pH, and carbonate chemistry. Anthropogenic impacts - especially ocean acidification - increase this variability, which may affect the living conditions of coastal species, particularly, calcifiers. We performed culture experiments on living benthic foraminifera to study the combined effects of lowered pH and salinity on the calcification abilities and survival of the coastal, calcitic species Ammonia sp. and Elphidium crispum. We found that in open ocean conditions (salinity ∼35) and lower pH than usual values for these species, the specimens displayed resistance to shell (test) dissolution for a longer time than in brackish conditions (salinity ∼5 to 20). However, the response was species specific as Ammonia sp. specimens survived longer than E. crispum specimens when placed in the same conditions of salinity and pH. Living, decalcified juveniles of Ammonia sp. were observed and we show that desalination is one cause for the decalcification. Finally, we highlight the ability of foraminifera to survive under Ω calc < 1, and that high salinity and [Ca 2+ ] as building blocks are crucial for the foraminiferal calcification process. Copyright © 2018 Elsevier Ltd. All rights reserved.
Hypoxia tolerance in reptiles, amphibians, and fishes: life with variable oxygen availability.
Bickler, Philip E; Buck, Leslie T
2007-01-01
The ability of fishes, amphibians, and reptiles to survive extremes of oxygen availability derives from a core triad of adaptations: profound metabolic suppression, tolerance of ionic and pH disturbances, and mechanisms for avoiding free-radical injury during reoxygenation. For long-term anoxic survival, enhanced storage of glycogen in critical tissues is also necessary. The diversity of body morphologies and habitats and the utilization of dormancy have resulted in a broad array of adaptations to hypoxia in lower vertebrates. For example, the most anoxia-tolerant vertebrates, painted turtles and crucian carp, meet the challenge of variable oxygen in fundamentally different ways: Turtles undergo near-suspended animation, whereas carp remain active and responsive in the absence of oxygen. Although the mechanisms of survival in both of these cases include large stores of glycogen and drastically decreased metabolism, other mechanisms, such as regulation of ion channels in excitable membranes, are apparently divergent. Common themes in the regulatory adjustments to hypoxia involve control of metabolism and ion channel conductance by protein phosphorylation. Tolerance of decreased energy charge and accumulating anaerobic end products as well as enhanced antioxidant defenses and regenerative capacities are also key to hypoxia survival in lower vertebrates.
Improving Defibrillation Efficiency in Area Schools.
Thomas, Vincent C; Shen, Jay J; Stanley, Ramona; Dahlke, Jeffrey; McPartlin, Sheri; Row, Lynn
2016-07-01
Sudden cardiac arrest (SCA) in the young is a rare event but the effects can be devastating. We sought to identify variables that would lead to an improvement in time to defibrillation (TDFB), a previously noted factor significantly influencing survival from cardiac arrest. During the 2013-2014 academic year, the Clark county school district performed quarterly drills to practice the coordinated automated external defibrillator (AED) response. Variables including school, AED carrier, and drill characteristics were measured to determine influence on TDFB. Schools were grouped by TDFB at a cutoff of three minutes. Characteristics were sought for schools with TDFB below three minutes. A mixed regression model taking into account repeated measures was created to determine which variables influenced TDFB. Time to overhead announcement, distance of AED from drill site, and time to setup AED were the variables influencing TDFB with statistical significance (P <.01). This study supports the notion of early recognition, announcement, and close proximity to an AED during a SCA to ensure an early TDFB. These results are consistent with basic life support and the chain of survival tenets of the American Heart Association. © 2016 Wiley Periodicals, Inc.
Horswill, Catharine; Matthiopoulos, Jason; Green, Jonathan A; Meredith, Michael P; Forcada, Jaume; Peat, Helen; Preston, Mark; Trathan, Phil N; Ratcliffe, Norman
2014-01-01
Understanding the demographic response of free-living animal populations to different drivers is the first step towards reliable prediction of population trends. Penguins have exhibited dramatic declines in population size, and many studies have linked this to bottom-up processes altering the abundance of prey species. The effects of individual traits have been considered to a lesser extent, and top-down regulation through predation has been largely overlooked due to the difficulties in empirically measuring this at sea where it usually occurs. For 10 years (2003–2012), macaroni penguins (Eudyptes chrysolophus) were marked with subcutaneous electronic transponder tags and re-encountered using an automated gateway system fitted at the entrance to the colony. We used multistate mark–recapture modelling to identify the different drivers influencing survival rates and a sensitivity analysis to assess their relative importance across different life stages. Survival rates were low and variable during the fledging year (mean = 0·33), increasing to much higher levels from age 1 onwards (mean = 0·89). We show that survival of macaroni penguins is driven by a combination of individual quality, top-down predation pressure and bottom-up environmental forces. The relative importance of these covariates was age specific. During the fledging year, survival rates were most sensitive to top-down predation pressure, followed by individual fledging mass, and finally bottom-up environmental effects. In contrast, birds older than 1 year showed a similar response to bottom-up environmental effects and top-down predation pressure. We infer from our results that macaroni penguins will most likely be negatively impacted by an increase in the local population size of giant petrels. Furthermore, this population is, at least in the short term, likely to be positively influenced by local warming. More broadly, our results highlight the importance of considering multiple causal effects across different life stages when examining the survival rates of seabirds. PMID:24846695
A retrospective study of feline gastric lymphoma in 16 chemotherapy-treated cats.
Gustafson, Tanya L; Villamil, Armando; Taylor, Bonnie E; Flory, Andrea
2014-01-01
The purposes of this study were to describe cases of feline gastric lymphoma with regards to signalment, clinical presentation, laboratory and ancillary study findings, response to therapy, and outcomes and to identify prognostic variables. Sixteen cats with stage I and II gastric lymphoma treated with chemotherapy were included in this study. Seventy-five percent of cats experienced remission. Overall, first remission duration was 108 days. Response to treatment was prognostic as in other types of feline lymphoma. Cats with a complete remission (CR) had longer survival times compared with cats with a partial remission (PR). Sex and treatment with a rescue protocol were found to be prognostic with castrated males having longer survivals than spayed females. Cats that received rescue chemotherapy had shorter first remission durations than those that did not. Prior treatment with steroids and stage were not found to be significant prognostic variables. This study characterizes gastric lymphoma treated with chemotherapy in cats. Further studies are needed to determine the comparative efficacy of surgical and chemotherapeutic treatments for feline gastric lymphoma.
Bahnassy, Abeer A; Fawzy, Mohamed; El-Wakil, Mohamed; Zekri, Abdel-Rahman N; Abdel-Sayed, Ahmed; Sheta, Marwa
2015-03-01
Hepatoblastoma (HB) is an embryonal tumor of the liver in children. Prognosis and response to treatment in HB are highly variable. Cancer stem cells (CSCs) constitute a population of cells, which contribute to the development and progression of many tumors. However, their role in HB is not well defined yet. We assessed the prognostic and predictive values of some CSC markers in HB patients. Protein and messenger RNA expressions of the CSC markers CD133, CD90, and CD44 were assessed in 43 HB patients and 20 normal hepatic tissues using immunohistochemistry and quantitative real-time polymerase chain reaction. The expression levels of these markers were correlated to standard prognostic factors, patients' response to treatment, overall survival (OS), and disease-free survival (DFS). CD44, CD90, and CD133 proteins were detected in 48.8%, 32.6%, and 48.8% compared with 46.5%, 41.7%, and 58.1% RNA, respectively (concordance, 77.8%-96%). None of the normal tissue samples was positive for any of the markers. Significant correlations were reported between α-fetoprotein and both CD44 and CD133 (P = 0.02) as well as between tumor types CD90 and CD133 (P = 0.009). Reduced OS correlated with CD44, CD90, and CD133 expressions (P < 0.001), advanced stage (P < 0.001), response to treatment (P < 0.001), and total excision of the tumor. Reduced DFS correlated with CD44 and CD133 expressions (P < 0.001) only. In conclusion, CD133, CD44, and CD90 could be used as prognostic and predictive markers in HB. High expression of these markers is significantly associated with poor response to treatment and reduced survival. Moreover, complete surgical resection and systemic chemotherapy are essential to achieve good response and prolonged survival, especially in early stage patients. Copyright © 2015 Elsevier Inc. All rights reserved.
Detecting subject-specific activations using fuzzy clustering
Seghier, Mohamed L.; Friston, Karl J.; Price, Cathy J.
2007-01-01
Inter-subject variability in evoked brain responses is attracting attention because it may reflect important variability in structure–function relationships over subjects. This variability could be a signature of degenerate (many-to-one) structure–function mappings in normal subjects or reflect changes that are disclosed by brain damage. In this paper, we describe a non-iterative fuzzy clustering algorithm (FCP: fuzzy clustering with fixed prototypes) for characterizing inter-subject variability in between-subject or second-level analyses of fMRI data. The approach identifies the contribution of each subject to response profiles in voxels surviving a classical F-statistic criterion. The output identifies subjects who drive activation in specific cortical regions (local effects) or in voxels distributed across neural systems (global effects). The sensitivity of the approach was assessed in 38 normal subjects performing an overt naming task. FCP revealed that several subjects had either abnormally high or abnormally low responses. FCP may be particularly useful for characterizing outlier responses in rare patients or heterogeneous populations. In these cases, atypical activations may not be detected by standard tests, under parametric assumptions. The advantage of using FCP is that it searches all voxels systematically and can identify atypical activation patterns in a quantitative and unsupervised manner. PMID:17478103
Gundogdu, Ozan; da Silva, Daiani T; Mohammad, Banaz; Elmi, Abdi; Wren, Brendan W; van Vliet, Arnoud H M; Dorrell, Nick
2016-01-01
Campylobacter jejuni is the leading cause of bacterial foodborne diarrhoeal disease worldwide. Despite the microaerophilic nature of the bacterium, C. jejuni can survive the atmospheric oxygen conditions in the environment. Bacteria that can survive either within a host or in the environment like C. jejuni require variable responses to survive the stresses associated with exposure to different levels of reactive oxygen species. The MarR-type transcriptional regulators RrpA and RrpB have recently been shown to play a role in controlling both the C. jejuni oxidative and aerobic stress responses. Analysis of 3,746 C. jejuni and 486 C. coli genome sequences showed that whilst rrpA is present in over 99% of C. jejuni strains, the presence of rrpB is restricted and appears to correlate with specific MLST clonal complexes (predominantly ST-21 and ST-61). C. coli strains in contrast lack both rrpA and rrpB . In C. jejuni rrpB + strains, the rrpB gene is located within a variable genomic region containing the IF subtype of the type I Restriction-Modification ( hsd ) system, whilst this variable genomic region in C. jejuni rrpB - strains contains the IAB subtype hsd system and not the rrpB gene. C. jejuni rrpB - strains exhibit greater resistance to peroxide and aerobic stress than C. jejuni rrpB + strains. Inactivation of rrpA resulted in increased sensitivity to peroxide stress in rrpB + strains, but not in rrpB - strains. Mutation of rrpA resulted in reduced killing of Galleria mellonella larvae and enhanced biofilm formation independent of rrpB status. The oxidative and aerobic stress responses of rrpB - and rrpB + strains suggest adaptation of C. jejuni within different hosts and niches that can be linked to specific MLST clonal complexes.
NASA Astrophysics Data System (ADS)
Hapugoda, J. C.; Sooriyarachchi, M. R.
2017-09-01
Survival time of patients with a disease and the incidence of that particular disease (count) is frequently observed in medical studies with the data of a clustered nature. In many cases, though, the survival times and the count can be correlated in a way that, diseases that occur rarely could have shorter survival times or vice versa. Due to this fact, joint modelling of these two variables will provide interesting and certainly improved results than modelling these separately. Authors have previously proposed a methodology using Generalized Linear Mixed Models (GLMM) by joining the Discrete Time Hazard model with the Poisson Regression model to jointly model survival and count model. As Aritificial Neural Network (ANN) has become a most powerful computational tool to model complex non-linear systems, it was proposed to develop a new joint model of survival and count of Dengue patients of Sri Lanka by using that approach. Thus, the objective of this study is to develop a model using ANN approach and compare the results with the previously developed GLMM model. As the response variables are continuous in nature, Generalized Regression Neural Network (GRNN) approach was adopted to model the data. To compare the model fit, measures such as root mean square error (RMSE), absolute mean error (AME) and correlation coefficient (R) were used. The measures indicate the GRNN model fits the data better than the GLMM model.
Cyjon, A; Neuman-Levin, M; Rakowsky, E; Greif, F; Belinky, A; Atar, E; Hardoff, R; Brenner, B; Sulkes, A
2001-01-01
This study was designed to determine response rate, survival and toxicity associated with combination chemotherapy delivered intra-arterially to liver in patients with hepatic metastases of colorectal origin refractory to standard systemic treatment. A total of 28 patients who failed prior systemic treatment with fluoropyrimidines received a median of 5 cycles of intra-arterial treatment consisting of 5-fluorouracil 700 mg/m2/d, leucovorin 120 mg/m2/d, and cisplatin 20 mg/m2/d for 5 consecutive days. Cycles were repeated at intervals of 5–6 weeks. A major response was achieved in 48% of patients: complete response in 8% and partial response in 40%. The median duration of response was 11.5 months. Median survival was 12 months at a median follow up of 12 months. On multivariate analysis, the only variables with a significant impact on survival were response to treatment and performance status. Toxicity was moderate: grades III–IV neutropenia occurred in 29% of patients. Most of the patients complained of fatigue lasting for a few days following each cycle. There were no cases of hepatobiliary toxicity. These findings indicate that regional intra-arterial treatment should be considered in selected patients with predominantly liver disease following failure of standard treatment. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11506487
In vivo response of Mesocestoides vogae to human insulin.
Canclini, L; Esteves, A
2009-02-01
Successful host invasion by parasitic helminths involves detection and appropriate response to a range of host-derived signals. Insulin signal response pathways are ancient and highly-conserved throughout the metazoans. However, very little is known about helminth insulin signalling and the potential role it may play in host-parasite interactions. The response of Mesocestoides vogae (Cestoda: Cyclophyllidea) larvae to human insulin was investigated, focusing on tyrosine-phosphorylation status, glucose content, survival and asexual reproduction rate. Parasite larvae were challenged with different levels of insulin for variable periods. The parameters tested were influenced by human insulin, and suggested a host-parasite molecular dialogue.
An evaluation of the seven-day toxicity test with Americamysis bahia (formerly Mysidopsis bahia)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lussier, S.M.; Kuhn, A.; Comeleo, R.
The 7-d test measuring survival, growth, and fecundity of Americamysis bahia (formerly Mysidopsis bahia) was developed for estimating the chronic toxicity of effluents and associated receiving waters for National Pollutant Discharge Elimination System permits. Currently, this test and its derivatives are also used in toxicity identification evaluation (TIE), risk assessment, and other applications. To evaluate the relative sensitivity of three measurement endpoints (survival, growth, and fecundity), the authors analyzed results from 115 tests with effluents, organic or inorganic chemicals, and receiving waters suspected of being toxic. Controls for 78 of these achieved acceptable survival and growth. Fifty of these 78more » tests also achieved acceptable control fecundity. In the 47 tests with significant effects, survival was the most sensitive response in 57%, fecundity in 30%, and growth in 30%. There was little duplication in responses. Improving pretest holding conditions by decreasing the maximum density from {approximately}20 to 10 animals/L and increasing the temperature from {approximately}26 C to a range of 26 to 27 C improved the growth and fecundity in controls. Although the percentage of tests achieving acceptable control survival and growth decreased from 93 to 86%, the percentage achieving acceptable fecundity in controls increased from 60 to 97%. Seasonal differences in fecundity were detected among control groups. Although variable, fecundity is often the most sensitive measure of response. The 7-d mysid test estimates the chronic toxicity of effluents most effectively when all three endpoints are used.« less
Prognostic factors in multiple myeloma: selection using Cox's proportional hazard model.
Pasqualetti, P; Collacciani, A; Maccarone, C; Casale, R
1996-01-01
The pretreatment characteristics of 210 patients with multiple myeloma, observed between 1980 and 1994, were evaluated as potential prognostic factors for survival. Multivariate analysis according to Cox's proportional hazard model identified in the 160 dead patients with myeloma, among 26 different single prognostic variables, the following factors in order of importance: beta 2-microglobulin; bone marrow plasma cell percentage, hemoglobinemia, degree of lytic bone lesions, serum creatinine, and serum albumin. By analysis of these variables a prognostic index (PI), that considers the regression coefficients derived by Cox's model of all significant factors, was obtained. Using this it was possible to separate the whole patient group into three stages: stage I (PI < 1.485, 67 patients), stage II (PI: 1.485-2.090, 76 patients), and stage III (PI > 2.090, 67 patients), with a median survivals of 68, 36 and 13 months (P < 0.0001), respectively. Also the responses to therapy (P < 0.0001) and the survival curves (P < 0.00001) presented significant differences among the three subgroups. Knowledge of these factors could be of value in predicting prognosis and in planning therapy in patients with multiple myeloma.
Samson, Pamela; Robinson, Clifford; Bradley, Jeffrey; Lockhart, A Craig; Puri, Varun; Broderick, Stephen; Kreisel, Daniel; Krupnick, A Sasha; Patterson, G Alexander; Meyers, Bryan; Crabtree, Traves
2016-12-01
The aim of this study was to evaluate differences in pathologic complete response (pCR) rates and overall survival among patients receiving either neoadjuvant chemotherapy or chemoradiation before esophagectomy for locally advanced esophageal cancer. Patients with esophageal cancer receiving either neoadjuvant chemotherapy or chemoradiation before esophagectomy were identified using the National Cancer Database. Univariate analysis compared patient, tumor, and postoperative outcome characteristics. Logistic regression was performed to identify variables associated with achieving pCR. Kaplan-Meier analysis was performed to compare overall median survival by neoadjuvant therapy type and pCR status. Finally, a Cox proportional hazards model was fitted to identify variables associated with increased mortality hazard. From 2006 to 2012, a total of 916 of 7338 of patients (12.5%) received neoadjuvant chemotherapy whereas 6422 (87.5%) received neoadjuvant chemoradiation. Patients who received neoadjuvant chemoradiation were more likely to achieve a pCR (17.2% versus 6.4%, p < 0.001) and less likely to have positive margins (5.6% versus 11.5%, p < 0.001) than were patients who received neoadjuvant chemotherapy, with no difference in 30- or 90-day mortality. Achieving a pCR was associated with improved overall median survival (59.5 ± 4.0 months versus 30.1 ± 0.76 months for those with persistent disease, p < 0.001). On logistic regression, neoadjuvant chemoradiation therapy was independently associated with achieving a pCR (OR = 2.75, 95% confidence interval: 2.01-3.77, p < 0.001). Despite improvement in the pCR rate with neoadjuvant chemoradiation, neoadjuvant therapy type was not independently associated with long-term survival (hazard ratio = 1.12; 95% confidence interval: 0.97-1.30, p = 0.12). Although neoadjuvant chemoradiation is more successful in downstaging esophageal cancer before esophagectomy, it was not independently prognostic for improved long-term survival. Other factors affecting long-term survival among pathologic complete responders and among patients with persistent disease should be investigated to clarify this association. Copyright © 2016 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.
Lee D. Hansen; Bruce N. Smith; Richard S. Criddle; J. N. Church
2001-01-01
The Arrhenius activation energies, and therefore temperature coefficients, for rates of catabolic production of ATP and for anabolic use of ATP differ. Because the intracellular concentration of ATP and the phosphorylation potential must be controlled within a narrow range for cell survival, a mechanism must exist to balance these rates during temperature variation in...
USDA-ARS?s Scientific Manuscript database
Response surface methodology was applied to investigate the combined effect of apple skin polyphenols (ASP), acetic acid (AA), oregano essential oil (O) and carvacrol (C) on the inactivation of Salmonella on sliced cooked ham. A full factorial experimental design was employed with control variables ...
Ferrucci, Pier F; Minchella, Ida; Mosconi, Massimo; Gandini, Sara; Verrecchia, Francesco; Cocorocchio, Emilia; Passoni, Claudia; Pari, Chiara; Testori, Alessandro; Coco, Paola; Munzone, Elisabetta
2015-06-01
The combined treatment of dacarbazine with an antiangiogenic drug such as bevacizumab may potentiate the therapeutic effects of dacarbazine in metastatic melanoma (MM). Preliminary antitumour activity of dacarbazine plus bevacizumab is evaluated, together with the toxicity and safety profile, in MM patients. This prospective, open-label, phase II study included patients with previously untreated MM or unresectable melanoma. Patients received dacarbazine and bevacizumab until progressive disease or unacceptable toxicity. The primary efficacy variable was the overall response rate. The secondary efficacy parameters included duration of response, duration of stable disease, time to progression/progression-free survival, time to treatment failure and overall survival. The safety analysis included recordings of adverse events and exposure to study treatment. The intention-to-treat population included 37 patients (24 men and 13 women, mean age 54.2±13.1 years). Overall response rate was 18.9% (seven patients achieved a response) and clinical benefit was 48.6%. In patients who achieved a response, the median duration of response was 16.9 months and the median duration of stable disease was 12.5 months. The median time to progression/progression-free survival and time to treatment failure were 5.5 and 3.1 months, respectively. The median overall survival was 11.4 months. Almost all patients (94.6%) experienced at least one adverse event; however, no new area of toxicity of bevacizumab emerged. The dacarbazine/bevacizumab combination provides benefits compared with dacarbazine monotherapy in historical controls, with an acceptable safety profile. This combination appears to be a valid option in specific subgroups of patients, namely, those triple negative (BRAF, C-KIT and NRAS wild type) or with a BRAF mutation who have already received, or are not eligible for, immunomodulating or targeted agents.
Clinical findings and survival in 56 sick neonatal New World camelids.
Bertin, F R; Squires, J M; Kritchevsky, J E; Taylor, S D
2015-01-01
Information pertaining to clinical presentation and outcome of neonatal New World camelids (NWC) is limited when compared to calves and foals. Values of variables at admission and subsequent treatment would predict survival in sick neonatal NWC. Fifty-six client-owned sick neonatal NWC presented over a 10-year period to the Purdue University Veterinary Teaching Hospital. A retrospective study was performed. Inclusion criteria were NWC less than 30 days of age with complete medical records that presented between 2000 and 2010. The median age at presentation was 1 day (range 1-20). The most common diagnoses were systemic inflammatory response syndrome (50%), congenital defects (41%), ophthalmic lesions (21%), sepsis (16%), and gastrointestinal diseases (16%). Sixty-six percent of NWC survived to discharge. Clinicopathologic findings on admission were variable and not specific for disorders. Factors associated with survival were absence of choanal atresia (P = .001, OR: 55.9 [2.5-1,232]), administration of llama plasma (P = .013, OR: 4.9 [1.4-17.7]), and antimicrobial treatment with trimethoprim-sulfamethoxazole (TMS) (P = .016, OR: 6.5 [1.3-32.2]). The use of antibiotics, particularly TMS, and llama plasma are recommended in sick neonatal NWC. Results from this study could contribute toward defining a NWC-specific sepsis scoring system. Copyright © 2014 by the American College of Veterinary Internal Medicine.
Survival of white-tailed deer neonates in Minnesota and South Dakota
Grovenburg, T.W.; Swanson, C.C.; Jacques, C.N.; Klaver, R.W.; Brinkman, T.J.; Burris, B.M.; Deperno, C.S.; Jenks, J.A.
2011-01-01
Understanding the influence of intrinsic (e.g., age, birth mass, and sex) and habitat factors on survival of neonate white-tailed deer improves understanding of population ecology. During 2002–2004, we captured and radiocollared 78 neonates in eastern South Dakota and southwestern Minnesota, of which 16 died before 1 September. Predation accounted for 80% of mortality; the remaining 20% was attributed to starvation. Canids (coyotes [Canis latrans], domestic dogs) accounted for 100% of predation on neonates. We used known fate analysis in Program MARK to estimate survival rates and investigate the influence of intrinsic and habitat variables on survival. We developed 2 a priori model sets, including intrinsic variables (model set 1) and habitat variables (model set 2; forested cover, wetlands, grasslands, and croplands). For model set 1, model {Sage-interval} had the lowest AICc (Akaike's information criterion for small sample size) value, indicating that age at mortality (3-stage age-interval: 0–2 weeks, 2–8 weeks, and >8 weeks) best explained survival. Model set 2 indicated that habitat variables did not further influence survival in the study area; β-estimates and 95% confidence intervals for habitat variables in competing models encompassed zero; thus, we excluded these models from consideration. Overall survival rate using model {Sage-interval} was 0.87 (95% CI = 0.83–0.91); 61% of mortalities occurred at 0–2 weeks of age, 26% at 2–8 weeks of age, and 13% at >8 weeks of age. Our results indicate that variables influencing survival may be area specific. Region-specific data are needed to determine influences of intrinsic and habitat variables on neonate survival before wildlife managers can determine which habitat management activities influence neonate populations.
Asparaginase and MOPP treatment of dogs with lymphoma.
Brodsky, E M; Maudlin, G N; Lachowicz, J L; Post, G S
2009-01-01
Dogs with multicentric lymphoma are treated with various cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP)-based chemotherapy protocols with variable success. To describe the progression-free survival (PFS) time and overall survival time (OST) of dogs with T-cell lymphoma or hypercalcemic lymphoma treated with L-asparaginase and mechlorethamine, vincristine, prednisone, procarbazine (MOPP). Fifty dogs with T-cell lymphoma, hypercalcemic lymphoma, or both treated at 3 referral veterinary hospitals. Retrospective study. Case were selected based on histologic or cytologic diagnosis of lymphoma; presence of the T-cell phenotype, presence of hypercalcemia or both; and absence of previous chemotherapy. The T-cell phenotype was determined by flow cytometry, immunocytochemistry, immunohistochemistry, or polymerase chain reaction of antigen receptor rearrangement. The overall response rate was 98% (78% complete response, 20% partial response). The median PFS for the entire study population was 189 days with 25% PFS at 939 days. The median OST for the entire study population was 270 days with 25% surviving 939 days. Twenty percent of the dogs required hospitalization for treatment related complications. L-Asp/MOPP chemotherapy might result in longer PFS and OST for dogs with multicentric T-cell lymphoma, dogs with hypercalcemic lymphoma or both, than achieved with CHOP.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ball, D
In this paper, we will examine how Russia's military and security forces might react to the detonation of a 10-kiloton nuclear weapon placed next to the walls surrounding the Kremlin. At the time of this 'big bang,' Putin is situated outside Moscow and survives the explosion. No one claims responsibility for the detonation. No other information is known. Numerous variables will determine how events ultimately unfold and how the military and security forces will respond. Prior to examining these variables in greater detail, it is imperative to elucidate first what we mean by Russia's military and security forces.
Management of metastatic renal cell carcinoma in the era of targeted therapies.
Webber, K; Cooper, A; Kleiven, H; Yip, D; Goldstein, D
2011-08-01
Metastatic renal cell cancer is associated with poor prognosis and survival and is resistant to conventional chemotherapy. Therapeutic targeting of molecular pathways for tumour angiogenesis and other specific activation mechanisms offers improved tumour response and prolonged survival. To conduct a retrospective audit of metastatic renal cell carcinoma patients treated with targeted therapies. Data were extracted from clinical records of patients undergoing targeted treatment between 2005 and 2009 at two hospital sites. Data collected included pathology, systemic therapy class, toxicity and survival. Univariate and multivariate survival analyses were performed. Sixty-one patients were treated with 102 lines of therapy with a median overall survival (OS) of 23 months, median time to failure of first-line treatment (TTF1) of 10 months and median time to failure of second-line treatment (TTF2) of 5.2 months. Time from first diagnosis to treatment >12 months was significantly associated with improved OS, longer TTF1, TTF2 and response to first-line anti-vascular endothelial growth factor receptor tyrosine kinase inhibitors (anti-VEGF TKI) therapy. Variables associated with tumour biology, natural history and the systemic inflammatory response were associated with improved OS and TTF1. Development of hypertension was predictive of anti-VEGF TKI outcome. Toxicities were as expected for each drug class. Survival and toxicity outcomes from two Australian sites are comparable to published data. The adverse event profile differs to conventional chemotherapy. Clinicians caring for patients with metastatic renal cancer will need to become familiar with these toxicities and their management as these agents enter widespread use. © 2011 The Authors. Internal Medicine Journal © 2011 Royal Australasian College of Physicians.
Inherited functional variants of the lymphocyte receptor CD5 influence melanoma survival
Potrony, Miriam; Carreras, Esther; Aranda, Fernando; Zimmer, Lisa; Puig-Butille, Joan-Anton; Tell-Martí, Gemma; Armiger, Noelia; Sucker, Antje; Giménez-Xavier, Pol; Martínez-Florensa, Mario; Carrera, Cristina; Malvehy, Josep; Schadendorf, Dirk; Puig, Susana; Lozano, Francisco
2017-01-01
Despite the recent progress in treatment options, malignant melanoma remains a deadly disease. Besides therapy, inherited factors might modulate clinical outcome, explaining in part widely varying survival rates. T-cell effector function regulators on antitumor immune responses could also influence survival. CD5, a T-cell receptor inhibitory molecule, contributes to the modulation of antimelanoma immune responses as deduced from genetically-modified mouse models. The CD5 SNPs rs2241002 (NM_014207.3:c.671C>T, p.Pro224Leu) and rs2229177 (NM_014207.3:c.1412C>T, p.Ala471Val) constitute an ancestral haplotype (Pro224-Ala471) that confers T-cell hyper-responsiveness and worsens clinical autoimmune outcome. The assessment of these SNPs on survival impact from two melanoma patient cohorts (Barcelona, N=493 and Essen, N=216) reveals that p.Ala471 correlates with a better outcome (OR= 0.57, 95% CI=0.33-0.99, Adj. P=0.043, in Barcelona OR=0.63, 95% CI=0.40-1.01, Adj. P=0.051, in Essen). While, p.Leu224 was associated with increased melanoma-associated mortality in both cohorts (OR=1.87, 95% CI=1.07-3.24, Adj. P=0.030 in Barcelona and OR=1.84, 95% CI=1.04-3.26, Adj. P=0.037, in Essen). Furthermore survival analyses showed that the Pro224-Ala471 haplotype in homozygosis improved melanoma survival in the entire set of patients (HR=0.27, 95% CI 0.11 to 0.67, Adj. P=0.005). These findings highlight the relevance of genetic variability in immune-related genes for clinical outcome in melanoma. PMID:27169428
Effects of multiple levels of social organization on survival and abundance.
Ward, Eric J; Semmens, Brice X; Holmes, Elizabeth E; Balcomb Iii, Ken C
2011-04-01
Identifying how social organization shapes individual behavior, survival, and fecundity of animals that live in groups can inform conservation efforts and improve forecasts of population abundance, even when the mechanism responsible for group-level differences is unknown. We constructed a hierarchical Bayesian model to quantify the relative variability in survival rates among different levels of social organization (matrilines and pods) of an endangered population of killer whales (Orcinus orca). Individual killer whales often participate in group activities such as prey sharing and cooperative hunting. The estimated age-specific survival probabilities and survivorship curves differed considerably among pods and to a lesser extent among matrilines (within pods). Across all pods, males had lower life expectancy than females. Differences in survival between pods may be caused by a combination of factors that vary across the population's range, including reduced prey availability, contaminants in prey, and human activity. Our modeling approach could be applied to demographic rates for other species and for parameters other than survival, including reproduction, prey selection, movement, and detection probabilities. Conservation Biology ©2010 Society for Conservation Biology. No claim to original US government works.
Maeno, Koutaro O.; Piou, Cyril; Ould Babah, Mohamed A.; Nakamura, Satoshi
2013-01-01
Locusts are grasshopper species that express phase polyphenism: modifying their behavior, morphology, coloration, life history and physiology in response to crowding. Desert locusts, Schistocerca gregaria, epigenetically modify progeny quality and quantity in response to crowding. Gregarious (crowded) females produce larger but fewer progeny than do solitarious (isolated) ones. The variability of progeny quality within single egg pod and the reasons why gregarious progeny have a better survival rate than solitarious ones remains unclear. This study investigated 1) the effects of rearing density on the variation in egg size within single egg pods 2) the starvation tolerance of hatchlings from mothers with different phases and 3) the physiological differences in hatchling energy reserve. Isolated females produced smaller but more eggs than did crowded ones. The variation in egg size within egg pods was greater in the latter than in the former. A negative relationship between egg size and number of eggs per egg pod was observed for both groups. Under starvation conditions, gregarious hatchlings survived significantly longer than solitarious ones. Among the solitarious hatchlings, the survival time was longer with increased hatchling body size. However, small individuals survived as long as large ones among the gregarious hatchlings. The percentage of water content per fresh body weight was almost equal between the two phases, before and after starvation. In contrast, the percentage of lipid content per dry body weight was significantly higher in gregarious hatchlings than in solitarious ones before starvation, but became almost equal after starvation. These results demonstrate that female locusts not only trade-off to modify their progeny size and number, but also vary progenies' energy reserves. We hypothesize that gregarious females enhance their fitness by producing progeny differently adapted to high environmental variability and particularly to starvation conditions. PMID:24363645
Psallidas, Ioannis; Kanellakis, Nikolaos I; Gerry, Stephen; Thézénas, Marie Laëtitia; Charles, Philip D; Samsonova, Anastasia; Schiller, Herbert B; Fischer, Roman; Asciak, Rachelle; Hallifax, Robert J; Mercer, Rachel; Dobson, Melissa; Dong, Tao; Pavord, Ian D; Collins, Gary S; Kessler, Benedikt M; Pass, Harvey I; Maskell, Nick; Stathopoulos, Georgios T; Rahman, Najib M
2018-06-13
The prevalence of malignant pleural effusion is increasing worldwide, but prognostic biomarkers to plan treatment and to understand the underlying mechanisms of disease progression remain unidentified. The PROMISE study was designed with the objectives to discover, validate, and prospectively assess biomarkers of survival and pleurodesis response in malignant pleural effusion and build a score that predicts survival. In this multicohort study, we used five separate and independent datasets from randomised controlled trials to investigate potential biomarkers of survival and pleurodesis. Mass spectrometry-based discovery was used to investigate pleural fluid samples for differential protein expression in patients from the discovery group with different survival and pleurodesis outcomes. Clinical, radiological, and biological variables were entered into least absolute shrinkage and selection operator regression to build a model that predicts 3-month mortality. We evaluated the model using internal and external validation. 17 biomarker candidates of survival and seven of pleurodesis were identified in the discovery dataset. Three independent datasets (n=502) were used for biomarker validation. All pleurodesis biomarkers failed, and gelsolin, macrophage migration inhibitory factor, versican, and tissue inhibitor of metalloproteinases 1 (TIMP1) emerged as accurate predictors of survival. Eight variables (haemoglobin, C-reactive protein, white blood cell count, Eastern Cooperative Oncology Group performance status, cancer type, pleural fluid TIMP1 concentrations, and previous chemotherapy or radiotherapy) were validated and used to develop a survival score. Internal validation with bootstrap resampling and external validation with 162 patients from two independent datasets showed good discrimination (C statistic values of 0·78 [95% CI 0·72-0·83] for internal validation and 0·89 [0·84-0·93] for external validation of the clinical PROMISE score). To our knowledge, the PROMISE score is the first prospectively validated prognostic model for malignant pleural effusion that combines biological and clinical parameters to accurately estimate 3-month mortality. It is a robust, clinically relevant prognostic score that can be applied immediately, provide important information on patient prognosis, and guide the selection of appropriate management strategies. European Respiratory Society, Medical Research Funding-University of Oxford, Slater & Gordon Research Fund, and Oxfordshire Health Services Research Committee Research Grants. Copyright © 2018 Elsevier Ltd. All rights reserved.
Intention-to-treat survival benefit of liver transplantation in patients with hepatocellular cancer.
Lai, Quirino; Vitale, Alessandro; Iesari, Samuele; Finkenstedt, Armin; Mennini, Gianluca; Spoletini, Gabriele; Hoppe-Lotichius, Maria; Vennarecci, Giovanni; Manzia, Tommaso M; Nicolini, Daniele; Avolio, Alfonso W; Frigo, Anna Chiara; Graziadei, Ivo; Rossi, Massimo; Tsochatzis, Emmanouil; Otto, Gerd; Ettorre, Giuseppe M; Tisone, Giuseppe; Vivarelli, Marco; Agnes, Salvatore; Cillo, Umberto; Lerut, Jan
2017-12-01
The debate about the best approach to select patients with hepatocellular cancer (HCC) waiting for liver transplantation (LT) is still ongoing. This study aims to identify the best variables allowing to discriminate between "high-" and "low-benefit" patients. To do so, the concept of intention-to-treat (ITT) survival benefit of LT has been created. Data of 2,103 adult HCC patients consecutively enlisted during the period 1987-2015 were analyzed. Three rigorous statistical steps were used in order to create the ITT survival benefit of LT: the development of an ITT LT and a non-LT survival model, and the individual prediction of the ITT survival benefit of LT defined as the difference between the median ITT survival with (based on the first model) and without LT (based on the second model) calculated for each enrolled patient. Four variables (Model for End-Stage Liver Disease, alpha-fetoprotein, Milan-Criteria status, and radiological response) displayed a high effect in terms of delta benefit. According to these risk factors, four benefit groups were identified. Patients with three to four factors ("no-benefit group"; n = 405 of 2,103; 19.2%) had no benefit of LT compared to alternative treatments. Conversely, patients without any risk factor ("large-benefit group"; n = 108; 5.1%) yielded the highest benefit from LT reaching 60 months. The ITT transplant survival benefit presented here allows physicians to better select HCC patients waiting for LT. The obtained stratification may lead to an improved and more equitable method of organ allocation. Patients without benefit should be de-listed, whereas patients with large benefit ratio should be prioritized for LT. (Hepatology 2017;66:1910-1919). © 2017 by the American Association for the Study of Liver Diseases.
The H-ARS Dose Response Relationship (DRR): Validation and Variables.
Plett, P Artur; Sampson, Carol H; Chua, Hui Lin; Jackson, William; Vemula, Sasidhar; Sellamuthu, Rajendran; Fisher, Alexa; Feng, Hailin; Wu, Tong; MacVittie, Thomas J; Orschell, Christie M
2015-11-01
Manipulations of lethally-irradiated animals, such as for administration of pharmaceuticals, blood sampling, or other laboratory procedures, have the potential to induce stress effects that may negatively affect morbidity and mortality. To investigate this in a murine model of the hematopoietic acute radiation syndrome, 20 individual survival efficacy studies were grouped based on the severity of the administration (Admn) schedules of their medical countermeasure (MCM) into Admn 1 (no injections), Admn 2 (1-3 injections), or Admn 3 (29 injections or 6-9 oral gavages). Radiation doses ranged from LD30/30 to LD95/30. Thirty-day survival of vehicle controls in each group was used to construct radiation dose lethality response relationship (DRR) probit plots, which were compared statistically to the original DRR from which all LDXX/30 for the studies were obtained. The slope of the Admn 3 probit was found to be significantly steeper (5.190) than that of the original DRR (2.842) or Admn 2 (2.009), which were not significantly different. The LD50/30 for Admn 3 (8.43 Gy) was less than that of the original DRR (8.53 Gy, p < 0.050), whereas the LD50/30 of other groups were similar. Kaplan-Meier survival curves showed significantly worse survival of Admn 3 mice compared to the three other groups (p = 0.007). Taken together, these results show that stressful administration schedules of MCM can negatively impact survival and that dosing regimens should be considered when constructing DRR to use in survival studies.
Villablanca, Judith G; Ji, Lingyun; Shapira-Lewinson, Adi; Marachelian, Araz; Shimada, Hiroyuki; Hawkins, Randall A; Pampaloni, Miguel; Lai, Hollie; Goodarzian, Fariba; Sposto, Richard; Park, Julie R; Matthay, Katherine K
2018-05-01
The New Approaches to Neuroblastoma Therapy Response Criteria (NANTRC) were developed to optimize response assessment in patients with recurrent/refractory neuroblastoma. Response predictors and associations of the NANTRC version 1.0 (NANTRCv1.0) and prognostic factors with outcome were analyzed. A retrospective analysis was performed of patients with recurrent/refractory neuroblastoma enrolled from 2000 to 2009 on 13 NANT Phase 1/2 trials. NANTRC overall response integrated CT/MRI (Response Evaluation Criteria in Solid Tumors [RECIST]), metaiodobenzylguanidine (MIBG; Curie scoring), and percent bone marrow (BM) tumor (morphology). Fourteen (6.9%) complete response (CR) and 14 (6.9%) partial response (PR) occurred among 203 patients evaluable for response. Five-year progression-free survival (PFS) was 16 ± 3%; overall survival (OS) was 27 ± 3%. Disease sites at enrollment included MIBG-avid lesions (100% MIBG trials; 84% non-MIBG trials), measurable CT/MRI lesions (48%), and BM (49%). By multivariable analysis, Curie score of 0 (P < 0.001), lower Curie score (P = 0.003), no measurable CT/MRI lesions (P = 0.044), and treatment on peripheral blood stem cell (PBSC) supported trials (P = 0.005) were associated with achieving CR/PR. Overall response of stable disease (SD) or better was associated with better OS (P < 0.001). In multivariable analysis, MYCN amplification (P = 0.037) was associated with worse PFS; measurable CT/MRI lesions (P = 0.041) were associated with worse OS; prior progressive disease (PD; P < 0.001/P < 0.001), Curie score ≥ 1 (P < 0.001; P = 0.001), higher Curie score (P = 0.048/0.037), and treatment on non-PBSC trials (P = < 0.001/0.003) were associated with worse PFS and OS. NANTRCv1.0 response of at least SD is associated with better OS in patients with recurrent/refractory neuroblastoma. Patient and tumor characteristics may predict response and outcome. Identifying these variables can optimize Phase 1/2 trial design to select novel agents for further testing. © 2018 Wiley Periodicals, Inc.
A metadata template for ocean acidification data
NASA Astrophysics Data System (ADS)
Jiang, L.
2014-12-01
Metadata is structured information that describes, explains, and locates an information resource (e.g., data). It is often coarsely described as data about data, and documents information such as what was measured, by whom, when, where, and how it was sampled, analyzed, with what instruments. Metadata is inherent to ensure the survivability and accessibility of the data into the future. With the rapid expansion of biological response ocean acidification (OA) studies, the lack of a common metadata template to document such type of data has become a significant gap for ocean acidification data management efforts. In this paper, we present a metadata template that can be applied to a broad spectrum of OA studies, including those studying the biological responses of organisms on ocean acidification. The "variable metadata section", which includes the variable name, observation type, whether the variable is a manipulation condition or response variable, and the biological subject on which the variable is studied, forms the core of this metadata template. Additional metadata elements, such as principal investigators, temporal and spatial coverage, platforms for the sampling, data citation are essential components to complete the template. We explain the structure of the template, and define many metadata elements that may be unfamiliar to researchers. For that reason, this paper can serve as a user's manual for the template.
Berger, Massimo; Albiani, Roberto; Sini, Bruno; Fagioli, Franca
2015-04-01
Extracorporeal photopheresis (ECP) has been shown as active therapy for graft-versus-host disease (GVHD). The aim was to ascertain the role of ECP in 71 patients with steroid-refractory or -dependent acute and chronic GVHD (aGVHD and cGVHD) with special focus on hematologic variables and GVHD staging classification. A total of 34 patients were treated for aGVHD and 37 for cGVHD. The overall response rate (ORR) for aGVHD was 65% and the complete aGVHD-free survival was 50% (95% confidence interval [CI], 36%-70%). The ORR for cGVHD response was 81% while the complete cGVHD-free survival was 50% (95% CI, 34%-73%). The aGVHD-free survival was associated with aGVHD grading (Grade II 81%, Grade III 33%, and Grade IV 0%, p ≤ 0.00) and the absence of visceral involvement (77% vs. 33%, p = 0.03). The cGVHD-free survival was associated with the female sex (67% vs. 25%, p = 0.01) and with the limited form according to the Seattle classification (67% vs. 20%, p = 0.003). No role for hematologic values or apheresis cell count was found, except for the cGVHD ORR (p = 0.037). Transplant-related mortality and overall survival were associated with ECP response 0% versus 54% (p = 0.0001) and 77% versus 45% (p = 0.03) for aGVHD patients and 7% versus 14% (p = 0.02) and 73% versus 20% (p = 0.0003) for cGVHD patients, respectively. While confirming a higher probability of GVHD responses for early GVHD, our study shows no role of hematologic values or apheresis cell count on GVHD response. © 2014 The Authors. Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.
Protein phosphatase 2A (PP2A) inhibitor CIP2A indicates resistance to radiotherapy in rectal cancer.
Birkman, Eva-Maria; Elzagheid, Adam; Jokilehto, Terhi; Avoranta, Tuulia; Korkeila, Eija; Kulmala, Jarmo; Syrjänen, Kari; Westermarck, Jukka; Sundström, Jari
2018-03-01
Preoperative (chemo)radiotherapy, (C)RT, is an essential part of the treatment of rectal cancer patients, but tumor response to this therapy among patients is variable. Thus far, there are no clinical biomarkers that could be used to predict response to (C)RT or to stratify patients into different preoperative treatment groups according to their prognosis. Overexpression of cancerous inhibitor of protein phosphatase 2A (CIP2A) has been demonstrated in several cancers and is frequently associated with reduced survival. Recently, high CIP2A expression has also been indicated to contribute to radioresistance in head and neck squamous cell carcinoma, but few studies have examined the connection between CIP2A and radiation response regarding other malignancies. We have evaluated CIP2A protein expression levels in relation to tumor regression after preoperative (C)RT and survival of rectal adenocarcinoma patients. The effects of CIP2A knockdown by siRNA on cell survival were further investigated in colorectal cancer cells exposed to radiation. Patients with low-CIP2A-expressing tumors had more frequently moderate or excellent response to long-course (C)RT than patients with high-CIP2A-expressing tumors. They also had higher 36-month disease-specific survival (DSS) rate in categorical analysis. In the multivariate analysis, low CIP2A expression level remained as an independent predictive factor for increased DSS. Suppression of CIP2A transcription by siRNA was found to sensitize colorectal cancer cells to irradiation and decrease their survival in vitro. In conclusion, these results suggest that by contributing to radiosensitivity of cancer cells, low CIP2A protein expression level associates with a favorable response to long-course (C)RT in rectal cancer patients. © 2018 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.
Baquero, Maria T; Lostritto, Karen; Gustavson, Mark D; Bassi, Kimberly A; Appia, Franck; Camp, Robert L; Molinaro, Annette M; Harris, Lyndsay N; Rimm, David L
2011-11-02
Microtubule associated proteins (MAPs) endogenously regulate microtubule stabilization and have been reported as prognostic and predictive markers for taxane response. The microtubule stabilizer, MAP-tau, has shown conflicting results. We quantitatively assessed MAP-tau expression in two independent breast cancer cohorts to determine prognostic and predictive value of this biomarker. MAP-tau expression was evaluated in the retrospective Yale University breast cancer cohort (n = 651) using tissue microarrays and also in the TAX 307 cohort, a clinical trial randomized for TAC versus FAC chemotherapy (n = 140), using conventional whole tissue sections. Expression was measured using the AQUA method for quantitative immunofluorescence. Scores were correlated with clinicopathologic variables, survival, and response to therapy. Assessment of the Yale cohort using Cox univariate analysis indicated an improved overall survival (OS) in tumors with a positive correlation between high MAP-tau expression and overall survival (OS) (HR = 0.691, 95% CI = 0.489-0.974; P = 0.004). Kaplan Meier analysis showed 10-year survival for 65% of patients with high MAP-tau expression compared to 52% with low expression (P = .006). In TAX 307, high expression was associated with significantly longer median time to tumor progression (TTP) regardless of treatment arm (33.0 versus 23.4 months, P = 0.010) with mean TTP of 31.2 months. Response rates did not differ by MAP-tau expression (P = 0.518) or by treatment arm (P = 0.584). Quantitative measurement of MAP-tau expression has prognostic value in both cohorts, with high expression associated with longer TTP and OS. Differences by treatment arm or response rate in low versus high MAP-tau groups were not observed, indicating that MAP-tau is not associated with response to taxanes and is not a useful predictive marker for taxane-based chemotherapy.
Demographic Responses To Climate Manipulations Across a Species Range
NASA Astrophysics Data System (ADS)
Oldfather, M. F.
2016-12-01
Species biogeographic responses to climate change will occur through the local extinction and establishment of populations. The overall performance of populations across a species range is shaped by the idiosyncratic sensitivities of demographic rates to the changing climate conditions. Heterogeneous topography partially decouples temperature and soil moisture presenting an opportunity to disentangle demographic sensitivity to multiple local climate variables and refine range shift predictions in response to complex climate change. Since 2013, I have monitored 16 populations of a long-lived alpine plant, Ivesia lycopodioides var. scandularis (Rosaceae) across the entirety of its altitudinal range in the arid White Mountains, CA (3350 - 4420m). I quantified microclimatic soil moisture and temperature, and the demographic rates of over 4,000 individuals. Demographic rates exhibited sensitivity to accumulated degree-days (ex. reproduction), soil volumetric water content (ex. germination), or the interaction between these climate variables (ex. survival). These observations motivated an experimental test of the relationship between demography and local climate with manipulations of increased summertime temperature and precipitation in nine populations. All demographic rates were sensitive to the climate manipulations and the magnitude of the demographic response depended on the population's location within the range. However, the modeled population growth rate was only minimally affected by the manipulations in most populations. The inverse responses of many of the demographic rates may allow populations to demographically buffer against the climate manipulations. However, in one low elevation edge population the negative effect of heating on survival overwhelmed the positive effect on germination, indicating that the capacity of populations to demographically buffer may have a limit.
Boldness towards novelty and translocation success in captive-raised, orphaned Tasmanian devils.
Sinn, David L; Cawthen, Lisa; Jones, Susan M; Pukk, Chrissy; Jones, Menna E
2014-01-01
Translocation of endangered animals is common, but success is often variable and/or poor. Despite its intuitive appeal, little is known with regards to how individual differences amongst translocated animals influence their post-release survival, growth, and reproduction. We measured consistent pre-release responses to novelty in a familiar environment (boldness; repeatability=0.55) and cortisol response in a group of captive-reared Tasmanian devils, currently listed as "Endangered" by the IUCN. The devils were then released at either a hard- or soft-release site within their mothers' population of origin, and individual growth, movement, reproduction (females only), and survival across 2-8 months post-release was measured. Sex, release method, cohort, behavior, and cortisol response did not affect post-release growth, nor did these factors influence the home range size of orphan devils. Final linear distances moved from the release site were impacted heavily by the release cohort, but translocated devils' movement overall was not different from that in the same-age wild devils. All orphan females of reproductive age were subsequently captured with offspring. Overall survival rates in translocated devils were moderate (∼42%), and were not affected by devil sex, release method, cohort, release weight, or pre-release cortisol response. Devils that survived during the study period were, however, 3.5 times more bold than those that did not (effect size r=0.76). Our results suggest that conservation managers may need to provide developmental conditions in captivity that promote a wide range of behaviors across individuals slated for wild release. © 2013 Wiley Periodicals, Inc.
Mallik, Shreyashee; Mallik, Girijasankar; Macabulos, Shireen Teves; Dorigo, Andrew
2016-04-01
Hypercalcaemia is a potentially fatal paraneoplastic complication of malignancy. It primarily manifests during the advanced phase of cancer, with the life expectancy of patients ranging from weeks to months. The mainstay of treatment is with bisphosphonates, but these are not frequently used in a palliative population due to potential conflict with goals of care. The goals of this study was to determine the reversibility of hypercalcaemia amongst patients whose underlying malignancy is not being treated and assess whether correction results in improvement in symptoms attributable to hypercalcaemia, while identifying risk factors that can predict responsiveness. We conducted a retrospective cohort study of 63 patients aged >18 years who were admitted to the St Joseph's Palliative Care Unit, Australia between 2007 and 2013, having evidence of malignancy-associated hypercalcaemia which was treated with bisphosphonates. We assessed the response to bisphosphonates based on improvement of symptoms attributable to hypercalcaemia, as well as a reduction in serum calcium. We used the Kaplan-Meier survival method and parametric survival analysis to estimate the effect of the independent variables on time till death. Thirty-six of sixty three patients achieved normocalcaemia following treatment with an intravenous bisphosphonate. Complete response was influenced by the number of instances of hypercalcaemia in the past and patient factors, such as age and albumin levels. We found that a reduction in calcium level was associated with a significantly prolonged survival, as well as symptomatic improvement, irrespective of whether normocalcaemia was achieved. Our study suggests that bisphosphonates can be recommended as a palliative measure for selected patients to improve symptoms and prolong survival.
TNF-α levels in cancer patients relate to social variables
Marucha, Phillip T.; Crespin, Timothy R.; Shelby, Rebecca A.; Andersen, Barbara L.
2008-01-01
Tumor necrosis factor-α (TNF-α) is an important cytokine associated with tumor regression and increased survival time for cancer patients. Research evidence relates immune factors (e.g., natural killer (NK) cell counts, NK cell lysis, lymphocyte profile, and lymphocyte proliferation) to the frequency and quality of social relations among cancer patients. We hypothesized that disruptions in social relations would be associated with lower TNF-α responses, and conversely, that reports of positive changes in social relations correlate with stronger responses. A prospective design measured changes in social activity and relationship satisfaction with a partner in 44 breast cancer patients at the time of cancer diagnosis, and initial surgery and 12 months later. Results indicated that patients reporting increased social activities or satisfaction exhibited stronger stimulated TNF-α responses. This is the first study to link changes in patient social relations with a cancer-relevant immune variable. PMID:15890493
Dazard, Jean-Eudes; Choe, Michael; LeBlanc, Michael; Rao, J. Sunil
2015-01-01
PRIMsrc is a novel implementation of a non-parametric bump hunting procedure, based on the Patient Rule Induction Method (PRIM), offering a unified treatment of outcome variables, including censored time-to-event (Survival), continuous (Regression) and discrete (Classification) responses. To fit the model, it uses a recursive peeling procedure with specific peeling criteria and stopping rules depending on the response. To validate the model, it provides an objective function based on prediction-error or other specific statistic, as well as two alternative cross-validation techniques, adapted to the task of decision-rule making and estimation in the three types of settings. PRIMsrc comes as an open source R package, including at this point: (i) a main function for fitting a Survival Bump Hunting model with various options allowing cross-validated model selection to control model size (#covariates) and model complexity (#peeling steps) and generation of cross-validated end-point estimates; (ii) parallel computing; (iii) various S3-generic and specific plotting functions for data visualization, diagnostic, prediction, summary and display of results. It is available on CRAN and GitHub. PMID:26798326
Andersen, N S; Jensen, M K; de Nully Brown, P; Geisler, C H
2002-02-01
This study presents the first large clinical analysis of 105 unselected mantle cell lymphoma (MCL) patients diagnosed from 1992 to 2000 in a well-defined Danish population. The annual incidences were 0.7/100000 for men and 0.2/100000 for women, with no significant change during the study period. Of 97 evaluable cases, 43% achieved a complete response (CR) after initial therapy. The median disease-free (DFS) and overall survival (OS) rates were 15 and 30 months, respectively. In multivariate analysis, splenomegaly (P=0.002), anaemia (P=0.0001) and age (P=0.002), but not the international prognostic index (IPI) and the Ann Arbor staging system, had an independent impact on survival. Moreover, in a sub-analysis of 45 younger MCL patients (<65 years), a trend towards an OS plateau of 58% was observed in cases without splenomegaly and anaemia (n=29). Thus, in contrast to previously suggested prognostic factors, these variables may prove useful for clinical decisions in a significant subset of MCL patients.
Contrael, Katlynd M; Killian, Alley J; Gregg, Sara R; Buchman, Timothy G; Coopersmith, Craig M
2013-10-01
The Surviving Sepsis Campaign suggests giving hydrocortisone to septic patients only if their "blood pressure is poorly responsive to fluid resuscitation and vasopressor therapy." Because the definition of "poorly responsive" is not provided, the purpose of this study was to identify prescribing triggers for hydrocortisone in septic shock. Retrospective chart review of patients with septic shock over 17 months, who received hydrocortisone, followed by a survey of all intensivists who attended in the study ICUs to determine whether provider attitudes matched clinical practice. Eight ICUs in an academic hospital and a hybrid academic/community hospital. A total of 155 patients with septic shock in whom vasopressors were initiated and hydrocortisone was prescribed. Ninety-nine patients (64%) were already receiving two vasopressors before hydrocortisone was prescribed. An additional 22 patients were on a single high-dose vasopressor prior to corticosteroid initiation. Of patients who survived to have their hydrocortisone dose changed, 57% had their corticosteroids tapered, whereas 43% were abruptly discontinued. Seventy-six percent of patients were no longer on vasopressors when the first dosing change was made. Twenty-seven out of 36 intensivists (75%) completed the survey. The majority (72%) defined "poorly responsive to vasopressors" as the presence of two vasopressors, and 70% stated that they required patients to be off vasopressors prior to altering the corticosteroid dose. Significant variability exists when corticosteroids are prescribed for septic shock, with the most common interpretation in our institution of "poorly responsive to fluid resuscitation and vasopressor therapy" being the presence of two vasopressors. The method and timing of corticosteroid discontinuation also differed among providers. Self-described prescribing patterns from intensivists closely matched their actual behavior, suggesting variability is due to differing interpretations of the guidelines themselves, rather than a deficit in knowledge translation.
Wright, Marvin N; Dankowski, Theresa; Ziegler, Andreas
2017-04-15
The most popular approach for analyzing survival data is the Cox regression model. The Cox model may, however, be misspecified, and its proportionality assumption may not always be fulfilled. An alternative approach for survival prediction is random forests for survival outcomes. The standard split criterion for random survival forests is the log-rank test statistic, which favors splitting variables with many possible split points. Conditional inference forests avoid this split variable selection bias. However, linear rank statistics are utilized by default in conditional inference forests to select the optimal splitting variable, which cannot detect non-linear effects in the independent variables. An alternative is to use maximally selected rank statistics for the split point selection. As in conditional inference forests, splitting variables are compared on the p-value scale. However, instead of the conditional Monte-Carlo approach used in conditional inference forests, p-value approximations are employed. We describe several p-value approximations and the implementation of the proposed random forest approach. A simulation study demonstrates that unbiased split variable selection is possible. However, there is a trade-off between unbiased split variable selection and runtime. In benchmark studies of prediction performance on simulated and real datasets, the new method performs better than random survival forests if informative dichotomous variables are combined with uninformative variables with more categories and better than conditional inference forests if non-linear covariate effects are included. In a runtime comparison, the method proves to be computationally faster than both alternatives, if a simple p-value approximation is used. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Quantifying expert diagnosis variability when grading tumor-infiltrating lymphocytes
NASA Astrophysics Data System (ADS)
Toro, Paula; Corredor, Germán.; Wang, Xiangxue; Arias, Viviana; Velcheti, Vamsidhar; Madabhushi, Anant; Romero, Eduardo
2017-11-01
Tumor-infiltrating lymphocytes (TILs) have proved to play an important role in predicting prognosis, survival, and response to treatment in patients with a variety of solid tumors. Unfortunately, currently, there are not a standardized methodology to quantify the infiltration grade. The aim of this work is to evaluate variability among the reports of TILs given by a group of pathologists who examined a set of digitized Non-Small Cell Lung Cancer samples (n=60). 28 pathologists answered a different number of histopathological images. The agreement among pathologists was evaluated by computing the Kappa index coefficient and the standard deviation of their estimations. Furthermore, TILs reports were correlated with patient's prognosis and survival using the Pearson's correlation coefficient. General results show that the agreement among experts grading TILs in the dataset is low since Kappa values remain below 0.4 and the standard deviation values demonstrate that in none of the images there was a full consensus. Finally, the correlation coefficient for each pathologist also reveals a low association between the pathologists' predictions and the prognosis/survival data. Results suggest the need of defining standardized, objective, and effective strategies to evaluate TILs, so they could be used as a biomarker in the daily routine.
Survival of patients with Ewing's sarcoma in Yazd-Iran.
Akhavan, Ali; Binesh, Fariba; Shamshiri, Hadi; Ghanadi, Fazllolah
2014-01-01
The Ewing's sarcoma family is a group of small round cell tumors which accounts for 10-15% of all primary bone neoplasms. The aim of this study was to evaluate the survival of Ewing's sarcoma patients in our province and to determine of influencing factors. All patients with documented Ewing's sarcoma/ primitive neuroectodermal tumor(PNET) family pathology were enrolled in this study during a period of eight years. For all of them local and systemic therapy were carried out. Overall and event free survival and prognostic factors were evaluated. Thirty two patients were enrolled in the study. The median age was 17.5 years. Twenty (65.2%) were male and 9 (28.1%) were aged 14 years or less. Mean disease free survival was 26.8 (95%CI; 13.8-39.9) months and five year disease free survival was 26%. Mean overall survival was 38.7 months (95%CI; 25.9-50.6) and median overall survival was 24 months. Five year overall survival was 25%. From the variables evaluated , only presence of metastatic disease at presentation (p value=0. 028) and complete response (p value =0. 006) had significant relations to overall survival. Survival of Ewing's sarcoma in our province is disappointing. It seems to be mostly due to less effective treatment. Administration of adequate chemotherapy dosage, resection of tumor with negative margins and precise assessment of irradiation volume may prove helpful.
Ng, Tsz Wai; Chan, Wing Lam; Lai, Ka Man
2017-12-01
Other than the needs for infection control to investigate the survival and inactivation of airborne bacterial pathogens, there has been a growing interest in exploring bacterial communities in the air and the effect of environmental variables on them. However, the innate biological mechanism influencing the bacterial viability is still unclear. In this study, a mutant-based approach, using Escherichia coli as a model, was used to prove the concept that common stress-response genes are important for airborne survival of bacteria. Mutants with a single gene knockout that are known to respond to general stress (rpoS) and oxidative stress (oxyR, soxR) were selected in the study. Low relative humidity (RH), 30-40% was more detrimental to the bacteria than high RH, >90%. The log reduction of ∆rpoS was always higher than that of the parental strain at all RH levels but the ∆oxyR had a higher log reduction than the parental strain at intermediate RH only. ∆soxR had the same viability compared to the parental strain at all RH levels. The results hint that although different types and levels of stress are produced under different RH conditions, stress-response genes always play a role in the bacterial viability. This study is the first reporting the association between stress-response genes and viability of airborne bacteria.
Hojman, D E
1996-03-01
This analysis involves empirically testing a theoretical model among 22 Central American and Caribbean countries during the 1990s that explains differences in infant and child mortality. Explanatory measures capture demographic, economic, health care, and educational characteristics. The model is expected to allow for an assessment of the potential impact of structural adjustment and external debt. It is pointed out that birth rates and child mortality rates followed similar patterns over time and between countries. In this study's regression analyses all variables in the three models that explain infant mortality are exogenous: low birth weight, immunization, gross domestic product per capita, years of schooling for women, population/nurse, and debt as a proportion of gross national product. As nations became richer, infant mortality declined. Infant mortality was lower in countries with high external debt. In models for explaining the birth rate and the child mortality rate, the best fit included variables for debt, real public expenditure on health care, water supply, and malnutrition. Analysis in a simultaneous model for 10 countries revealed that the birth rate and the child mortality rate were more responsive to shocks in exogenous variables in Barbados than in the Dominican Republic, and more responsive in the Dominican Republic than in Guatemala. The impact of each exogenous variable varied by country. In Barbados education was four times more effective in explaining the birth rate than water. In Guatemala, the most effective exogenous variable was malnutrition. Child mortality rates were affected more by multiplier effects. In richer countries, the most important impact on child survival was improved access to safe water, and the most important impact on the birth rate was increased real public expenditure on education per capita. For the poorest countries, findings suggest first improvement in malnutrition and then improvement in safe water supplies. Structural adjustment variables were found to have small impacts on the birth rate or limited impacts on child survival in poorer countries.
George, S; Primrose, J; Talbot, R; Smith, J; Mullee, M; Bailey, D; du Boulay, C; Jordan, H
2006-01-01
To investigate the relationship between survival in colorectal cancer patients and the number of lymph nodes examined by a pathologist, previously attributed to stage migration, we used data from a cohort of 5174 colorectal cancer patients recruited between September 1991 and August 1994, and followed-up for 5 years. We selected cases with data present on all prognostic variables, and stratified them into three groups by number of nodes examined. We made a multivariate survival comparison using a Cox regression model. In all, there were 3592 cases with data present on all prognostic variables. Patients who had >10 nodes identified had a significant survival advantage over those who had 5–10 identified, who had in turn a similar advantage over those with 0–4 identified (P<0.001). This effect was present in the whole group and at all Dukes' stages, although statistically significant only in stages B (P=0.004) and C (P=0.019). The effect remained after adjustment in a Cox regression model in which the mean number of nodes taken out by each surgical firm did not predict survival. In a sub-group with data on lymphocytic infiltration into the primary tumour a survival advantage was noted in those with prominent rather than mild infiltration (P<0.001): the former also tended to have more nodes found (P=0.015). Stage migration alone cannot explain these results, as survival advantages are noted across the whole population independent of stage. Lymphocytic infiltration into the primary tumour is prognostically important, and is associated with the number of nodes found. Reactive enlargement of lymph nodes in the mesentery may make them easier to find, reflect immune response to the tumour, and thus indirectly impact upon survival. PMID:16969342
Local-scale drivers of tree survival in a temperate forest.
Wang, Xugao; Comita, Liza S; Hao, Zhanqing; Davies, Stuart J; Ye, Ji; Lin, Fei; Yuan, Zuoqiang
2012-01-01
Tree survival plays a central role in forest ecosystems. Although many factors such as tree size, abiotic and biotic neighborhoods have been proposed as being important in explaining patterns of tree survival, their contributions are still subject to debate. We used generalized linear mixed models to examine the relative importance of tree size, local abiotic conditions and the density and identity of neighbors on tree survival in an old-growth temperate forest in northeastern China at three levels (community, guild and species). Tree size and both abiotic and biotic neighborhood variables influenced tree survival under current forest conditions, but their relative importance varied dramatically within and among the community, guild and species levels. Of the variables tested, tree size was typically the most important predictor of tree survival, followed by biotic and then abiotic variables. The effect of tree size on survival varied from strongly positive for small trees (1-20 cm dbh) and medium trees (20-40 cm dbh), to slightly negative for large trees (>40 cm dbh). Among the biotic factors, we found strong evidence for negative density and frequency dependence in this temperate forest, as indicated by negative effects of both total basal area of neighbors and the frequency of conspecific neighbors. Among the abiotic factors tested, soil nutrients tended to be more important in affecting tree survival than topographic variables. Abiotic factors generally influenced survival for species with relatively high abundance, for individuals in smaller size classes and for shade-tolerant species. Our study demonstrates that the relative importance of variables driving patterns of tree survival differs greatly among size classes, species guilds and abundance classes in temperate forest, which can further understanding of forest dynamics and offer important insights into forest management.
Local-Scale Drivers of Tree Survival in a Temperate Forest
Wang, Xugao; Comita, Liza S.; Hao, Zhanqing; Davies, Stuart J.; Ye, Ji; Lin, Fei; Yuan, Zuoqiang
2012-01-01
Tree survival plays a central role in forest ecosystems. Although many factors such as tree size, abiotic and biotic neighborhoods have been proposed as being important in explaining patterns of tree survival, their contributions are still subject to debate. We used generalized linear mixed models to examine the relative importance of tree size, local abiotic conditions and the density and identity of neighbors on tree survival in an old-growth temperate forest in northeastern China at three levels (community, guild and species). Tree size and both abiotic and biotic neighborhood variables influenced tree survival under current forest conditions, but their relative importance varied dramatically within and among the community, guild and species levels. Of the variables tested, tree size was typically the most important predictor of tree survival, followed by biotic and then abiotic variables. The effect of tree size on survival varied from strongly positive for small trees (1–20 cm dbh) and medium trees (20–40 cm dbh), to slightly negative for large trees (>40 cm dbh). Among the biotic factors, we found strong evidence for negative density and frequency dependence in this temperate forest, as indicated by negative effects of both total basal area of neighbors and the frequency of conspecific neighbors. Among the abiotic factors tested, soil nutrients tended to be more important in affecting tree survival than topographic variables. Abiotic factors generally influenced survival for species with relatively high abundance, for individuals in smaller size classes and for shade-tolerant species. Our study demonstrates that the relative importance of variables driving patterns of tree survival differs greatly among size classes, species guilds and abundance classes in temperate forest, which can further understanding of forest dynamics and offer important insights into forest management. PMID:22347996
Merckx, Thomas; Serruys, Mélanie; Van Dyck, Hans
2015-04-01
Recent anthropogenic eutrophication has meant that host plants of nettle-feeding insects became quasi-omnipresent in fertile regions of Western Europe. However, host plant resource quality - in terms of microclimate and nutritional value - may vary considerably between the 'original' forest habitat and 'recent' agricultural habitat. Here, we compared development in both environmental settings using a split-brood design, so as to explore to what extent larval survival and adult morphology in the nettle-feeding butterfly Aglais urticae are influenced by the anthropogenic environment. Nettles along field margins had higher C/N ratios and provided warmer microclimates to larvae. Larvae developed 20% faster and tended to improve their survival rates, on the agricultural land compared to woodland. Our split-brood approach indicated plastic responses within families, but also family effects in the phenotypic responses. Adult males and females had darker wing pigmentation in the drier and warmer agricultural environment, which contrasts with the thermal melanism hypothesis. Developmental plasticity in response to this microclimatically different and more variable habitat was associated with a broader phenotypic parameter space for the species. Both habitat expansion and developmental plasticity are likely contributors to the ecological and evolutionary success of these nettle-feeding insects in anthropogenic environments under high nitrogen load.
Impact of tumor grade on prognosis in pancreatic cancer: should we include grade in AJCC staging?
Wasif, Nabil; Ko, Clifford Y; Farrell, James; Wainberg, Zev; Hines, Oscar J; Reber, Howard; Tomlinson, James S
2010-09-01
AJCC staging of pancreatic cancer (PAC) is used to determine prognosis, yet survival within each stage shows wide variation and remains unpredictable. We hypothesized that tumor grade might be responsible for some of this variation and that the addition of grade to current AJCC staging would provide improved prognostication. The Surveillance, Epidemiology, and End Results (SEER) database (1991-2005) was used to identify 8082 patients with resected PAC. The impact of grade on overall and stage-specific survival was assessed using Cox regression analysis. Variables in the model were age, sex, tumor size, lymph node status, and tumor grade. For each AJCC stage, survival was significantly worse for high-grade versus low-grade tumors. On multivariate analysis, high tumor grade was an independent predictor of survival for the entire cohort (hazard ratio [HR] 1.40, 95% confidence interval [95% CI] 1.31-1.48) as well as for stage I (HR 1.28, 95% CI 1.07-1.54), stage IIA (HR 1.43, 95% CI 1.26-1.61), stage IIB (HR 1.38, 95% CI 1.27-1.50), stage III (HR 1.28, 95% CI 1.02-1.59), and stage IV (HR 1.58, 95% CI 1.21-2.05) patients. The addition of grade to staging results in a statistically significant survival discrimination between all stages. Tumor grade is an important prognostic variable of survival in PAC. We propose a novel staging system incorporating grade into current AJCC staging for pancreas cancer. The improved prognostication is more reflective of tumor biology and may impact therapy decisions and stratification of future clinical trials.
Konlaan, B B; Bygren, L O; Johansson, S E
2000-09-01
The aim of this study was to ascertain the possible influence of attending various kinds of cultural events or visiting cultural institutions as a determinant of survival. A cohort of individuals aged 25-74 years from a random sample were interviewed by trained non-medical interviewers in 1982 and 1983. The interviews covered standard-of-living variables. Our independent variables covered visiting cultural institutions and attendance at cultural events, reading books or periodicals, and music making. The non-response rate was about 25%. The cohort was followed with respect to survival for 14 years up to 31st December 1996. The background covariates that were used for control purposes were age, sex, cash buffer, educational standard, long-term disease, smoking, and physical exercise. Our setting was the Swedish survey of living conditions among the adult Swedish population aged 25-74 years. About 10,609 individuals were interviewed in 1982 and 1983. The outcome measure was survival until 31st December 1996. In all, 916 men and 600 women died during this period. We found a higher mortality risk for those people who rarely visited the cinema, concerts, museums, or art exhibitions compared with those visiting them most often. The significant relative risks ranging between RR 1.14 (95% CI. 1.01-1.31) of attending art exhibitions, and RR 1.42 (CI. 1.25-1.60) of attending museums, when adjusting for the nine other variables. Visits to the cinema and concerts gave significant RR in between. We could not discern any beneficial effect of attending the theatre, church service or sports event as a spectator or any effect of reading or music making. Our conclusion is that attendance at certain kinds of cultural events may have a beneficial effect on longevity.
Pérez-Beteta, Julián; Molina-García, David; Ortiz-Alhambra, José A; Fernández-Romero, Antonio; Luque, Belén; Arregui, Elena; Calvo, Manuel; Borrás, José M; Meléndez, Bárbara; Rodríguez de Lope, Ángel; Moreno de la Presa, Raquel; Iglesias Bayo, Lidia; Barcia, Juan A; Martino, Juan; Velásquez, Carlos; Asenjo, Beatriz; Benavides, Manuel; Herruzo, Ismael; Revert, Antonio; Arana, Estanislao; Pérez-García, Víctor M
2018-07-01
Purpose To evaluate the prognostic and predictive value of surface-derived imaging biomarkers obtained from contrast material-enhanced volumetric T1-weighted pretreatment magnetic resonance (MR) imaging sequences in patients with glioblastoma multiforme. Materials and Methods A discovery cohort from five local institutions (165 patients; mean age, 62 years ± 12 [standard deviation]; 43% women and 57% men) and an independent validation cohort (51 patients; mean age, 60 years ± 12; 39% women and 61% men) from The Cancer Imaging Archive with volumetric T1-weighted pretreatment contrast-enhanced MR imaging sequences were included in the study. Clinical variables such as age, treatment, and survival were collected. After tumor segmentation and image processing, tumor surface regularity, measuring how much the tumor surface deviates from a sphere of the same volume, was obtained. Kaplan-Meier, Cox proportional hazards, correlations, and concordance indexes were used to compare variables and patient subgroups. Results Surface regularity was a powerful predictor of survival in the discovery (P = .005, hazard ratio [HR] = 1.61) and validation groups (P = .05, HR = 1.84). Multivariate analysis selected age and surface regularity as significant variables in a combined prognostic model (P < .001, HR = 3.05). The model achieved concordance indexes of 0.76 and 0.74 for the discovery and validation cohorts, respectively. Tumor surface regularity was a predictor of survival for patients who underwent complete resection (P = .01, HR = 1.90). Tumors with irregular surfaces did not benefit from total over subtotal resections (P = .57, HR = 1.17), but those with regular surfaces did (P = .004, HR = 2.07). Conclusion The surface regularity obtained from high-resolution contrast-enhanced pretreatment volumetric T1-weighted MR images is a predictor of survival in patients with glioblastoma. It may help in classifying patients for surgery. © RSNA, 2018 Online supplemental material is available for this article.
Pérez-Beteta, Julián; Molina-García, David; Ortiz-Alhambra, José A; Fernández-Romero, Antonio; Luque, Belén; Arregui, Elena; Calvo, Manuel; Borrás, José M; Meléndez, Bárbara; Rodríguez de Lope, Ángel; Moreno de la Presa, Raquel; Iglesias Bayo, Lidia; Barcia, Juan A; Martino, Juan; Velásquez, Carlos; Asenjo, Beatriz; Benavides, Manuel; Herruzo, Ismael; Revert, Antonio; Arana, Estanislao; Pérez-García, Víctor M
2018-04-03
Purpose To evaluate the prognostic and predictive value of surface-derived imaging biomarkers obtained from contrast material-enhanced volumetric T1-weighted pretreatment magnetic resonance (MR) imaging sequences in patients with glioblastoma multiforme. Materials and Methods A discovery cohort from five local institutions (165 patients; mean age, 62 years ± 12 [standard deviation]; 43% women and 57% men) and an independent validation cohort (51 patients; mean age, 60 years ± 12; 39% women and 61% men) from The Cancer Imaging Archive with volumetric T1-weighted pretreatment contrast-enhanced MR imaging sequences were included in the study. Clinical variables such as age, treatment, and survival were collected. After tumor segmentation and image processing, tumor surface regularity, measuring how much the tumor surface deviates from a sphere of the same volume, was obtained. Kaplan-Meier, Cox proportional hazards, correlations, and concordance indexes were used to compare variables and patient subgroups. Results Surface regularity was a powerful predictor of survival in the discovery (P = .005, hazard ratio [HR] = 1.61) and validation groups (P = .05, HR = 1.84). Multivariate analysis selected age and surface regularity as significant variables in a combined prognostic model (P < .001, HR = 3.05). The model achieved concordance indexes of 0.76 and 0.74 for the discovery and validation cohorts, respectively. Tumor surface regularity was a predictor of survival for patients who underwent complete resection (P = .01, HR = 1.90). Tumors with irregular surfaces did not benefit from total over subtotal resections (P = .57, HR = 1.17), but those with regular surfaces did (P = .004, HR = 2.07). Conclusion The surface regularity obtained from high-resolution contrast-enhanced pretreatment volumetric T1-weighted MR images is a predictor of survival in patients with glioblastoma. It may help in classifying patients for surgery. © RSNA, 2018 Online supplemental material is available for this article.
VALLADARES, FERNANDO; HERNÁNDEZ, LIBERTAD G.; DOBARRO, IKER; GARCÍA‐PÉREZ, CRISTINA; SANZ, RUBÉN; PUGNAIRE, FRANCISCO I.
2003-01-01
Different plant species and organs within a plant differ in their plastic response to light. These responses influence their performance and survival in relation to the light environment, which may range from full sunlight to deep shade. Plasticity, especially with regard to physiological features, is linked to a greater capacity to exploit high light and is usually low in shade‐tolerant species. Among photosynthetic organs, green stems, which represent a large fraction of the total photosynthetic area of certain species, are hypothesized to be less capable of adjustment to light than leaves, because of biomechanical and hydraulic constraints. The response to light by leaves and stems of six species of leguminous, green‐stemmed shrubs from dry and high‐light environments was studied by growing seedlings in three light environments: deep shade, moderate shade and sun (3, 30 and 100 % of full sunlight, respectively). Survival in deep shade ranged from 2 % in Retama sphaerocarpa to 74 % in Ulex europaeus. Survival was maximal at moderate shade in all species, ranging from 80 to 98 %. The six species differed significantly in their ratio of leaf to total photosynthetic area, which influenced their light response. Survival in deep shade increased significantly with increasing ratio of leaf to total photosynthetic area, and decreased with increasing plasticity in net photosynthesis and dark respiration. Responses to light differed between stems and leaves within each species. Mean phenotypic plasticity for the variables leaf or stem specific mass, chlorophyll content, chlorophyll a/b ratio, and carotenoid to chlorophyll ratio of leaves, was inversely related to that of stems. Although mean plasticity of stems increased with the ratio of leaf to total photosynthetic area, the mean plasticity of leaves decreased. Shrubs with green stems and a low ratio of leaf to total photosynthetic area are expected to be restricted to well‐lit habitats, at least during the seedling stage, owing to their inefficient light capture and the low plasticity of their stems. PMID:12646502
Hot temperatures during the dry season reduce survival of a resident tropical bird.
Woodworth, Bradley K; Norris, D Ryan; Graham, Brendan A; Kahn, Zachary A; Mennill, Daniel J
2018-05-16
Understanding how climate change will shape species distributions in the future requires a functional understanding of the demographic responses of animals to their environment. For birds, most of our knowledge of how climate influences population vital rates stems from research in temperate environments, even though most of Earth's avian diversity is concentrated in the tropics. We evaluated effects of Southern Oscillation Index (SOI) and local temperature and rainfall at multiple temporal scales on sex-specific survival of a resident tropical bird, the rufous-and-white wren Thryophilus rufalbus , studied over 15 years in the dry forests of northwestern Costa Rica. We found that annual apparent survival of males was 8% higher than females, more variable over time, and responded more strongly to environmental variation than female survival, which did not vary strongly with SOI or local weather. For males, mean and maximum local temperatures were better predictors of survival than either rainfall or SOI, with high temperatures during the dry season and early wet season negatively influencing survival. These results suggest that, even for species adapted to hot environments, further temperature increases may threaten the persistence of local populations in the absence of distributional shifts. © 2018 The Author(s).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gielda, Benjamin T., E-mail: Benjamin_gielda@rush.edu; Mehta, Par; Khan, Atif
Background: Preoperative concurrent chemoradiotherapy (CRT) is an accepted treatment for potentially resectable, locally advanced, non-small-cell lung cancer (NSCLC). We reviewed a decade of single institution experience with preoperative split-course CRT followed by surgical resection to evaluate survival and identify factors that may be helpful in predicting outcome. Methods and Materials: All patients treated with preoperative split-course CRT and resection at Rush University Medical Center (RUMC) between January 1999 and December 2008 were retrospectively analyzed. Endpoints included overall survival (OS), progression-free survival (PFS), local-regional progression-free survival (LRPFS), and distant metastasis-free survival (DMFS). Patient and treatment related variables were assessed for correlationmore » with outcomes. Results: A total of 54 patients were analyzed, 76% Stage IIIA, 18% Stage IIIB, and 6% oligometastatic. The pathologic complete response (pCR) rate was 31.5%, and the absence of nodal metastases (pN0) was 64.8%. Median OS and 3-year actuarial survival were 44.6 months and 50%, respectively. Univariate analysis revealed initial stage (p < 0.01) and percent weight change during CRT (p < 0.01) significantly correlated with PFS/OS. On multivariate analysis initial stage (HR, 2.4; 95% CI, 1.18-4.90; p = 0.02) and percent weight change (HR, 0.79; 95% CI, 0.67-0.93; p < 0.01) maintained significance with respect to OS. There were no cases of Grade 3+ esophagitis, and there was a single case of Grade 3 febrile neutropenia. Conclusions: The strong correlation between weight change during CRT and OS/PFS suggests that this clinical parameter may be useful as a complementary source of predictive information in addition to accepted factors such as pathological response.« less
Sánchez-Fayos, M P; Hernández Guío, C; Rivas, M C; Outeiriño, J; González-Campos, C; Lobo, F
1993-12-01
To evaluate in retrospect the response to therapy and long-term evolution of a series of primitive intestinal lymphomas. The series was comprised of 42 patients diagnosed in our hospital during 1960-1962. The mean age was 34.5 years (range, 3-73), the M/F ratio was 21/21, and the histopathology distributes as follows: high grade (HG), 24 cases, low grade (LG), 12 cases, and mixed (LG/HG), 6 cases. B/T immunophenotype: 40/2. Staging: IE1,29 cases, IIE2-IV, 11 cases. The treatment applied in the series was classified in various types: ample surgical resection (aSR), 21 cases; partial surgical resection (pSR), 9 cases; abdominal radiation therapy (RT), 7 cases; monochemotherapy (MCT), 7 cases, and polychemotherapy (PCT), 28 cases. The correlation of clinicobiological variables with immediate response to treatment was evaluated by means of the chi square test, and the acturial post-therapeutic survival curves in accordance to the life tables, differences being calculated by the log rank test. Small intestine was the commonest site of involvement, 31 cases; ileocecal region, 7 cases; colon, 2 cases, and colon plus small intestine, 2 cases. Regardless of therapy type, complete remission (CR) was attained in 20 patients (47.5%), partial remission in 5; 11 cases were unresponsive (26.5%) and early death occurred in 6 instances (14.2%). The acturial post-therapeutic survival offered an 8-year expectancy of 47%. The correlation between immediate complete response and 16 clinico-biologic variables showed favourable significance for tumoral proliferation index (i.e., Pc10-positive cells < 15%) and for therapeutic regimens including PCT+aSR. On the other hand, the necessity of emergency surgery for diagnosis was a poor-risk factor. The correlation between a post-therapeutic survival and 19 other variables showed the following as favorable data: female sex, tumour proliferative index (i.e., Pc10-positive cells < 15%), the use of PCT+aSR, and attaining CR. Poor-risk factors were the need of emergency surgery, multicentric lymphomatous involvement and serum LDH rates 350 UI/L. Although immediate response (CR) and long-term results (survival) were better in the patients with favourable histology (LG+LG/HG) and in those with loco-regional disease (stages IE-IE1), the differences had no statistical significance, possibly due to the low number of cases. 1) Even though these findings should be carefully evaluated, dut to lack of homogeneity of the series and the fact of being a retrospective study, the rate of CR in this series (47.5%) is similar to that of current studies. 2) Female sex, type of therapy, multifocal involvement, the need of emergency surgery and high LDH levels have significant value in univariate analyses.
Gut microbes contribute to variation in solid organ transplant outcomes in mice.
McIntosh, Christine M; Chen, Luqiu; Shaiber, Alon; Eren, A Murat; Alegre, Maria-Luisa
2018-05-25
Solid organ transplant recipients show heterogeneity in the occurrence and timing of acute rejection episodes. Understanding the factors responsible for such variability in patient outcomes may lead to improved diagnostic and therapeutic approaches. Rejection kinetics of transplanted organs mainly depends on the extent of genetic disparities between donor and recipient, but a role for environmental factors is emerging. We have recently shown that major alterations of the microbiota following broad-spectrum antibiotics, or use of germ-free animals, promoted longer skin graft survival in mice. Here, we tested whether spontaneous differences in microbial colonization between genetically similar individuals can contribute to variability in graft rejection kinetics. We compared rejection kinetics of minor mismatched skin grafts in C57BL/6 mice from Jackson Laboratory (Jax) and Taconic Farms (Tac), genetically similar animals colonized by different commensal microbes. Female Tac mice rejected skin grafts from vendor-matched males more quickly than Jax mice. We observed prolonged graft survival in Tac mice when they were exposed to Jax mice microbiome through co-housing or fecal microbiota transplantation (FMT) by gastric gavage. In contrast, exposure to Tac mice did not change graft rejection kinetics in Jax mice, suggesting a dominant suppressive effect of Jax microbiota. High-throughput sequencing of 16S rRNA gene amplicons from Jax and Tac mice fecal samples confirmed a convergence of microbiota composition after cohousing or fecal transfer. Our analysis of amplicon data associated members of a single bacterial genus, Alistipes, with prolonged graft survival. Consistent with this finding, members of the genus Alistipes were absent in a separate Tac cohort, in which fecal transfer from Jax mice failed to prolong graft survival. These results demonstrate that differences in resident microbiome in healthy individuals may translate into distinct kinetics of graft rejection, and contribute to interpersonal variability in graft outcomes. The association between Alistipes and prolonged skin graft survival in mice suggests that members of this genus might affect host physiology, including at sites distal to the gastrointestinal tract. Overall, these findings allude to a potential therapeutic role for specific gut microbes to promote graft survival through the administration of probiotics, or FMT.
Mainou-Fowler, T; Copplestone, J A; Prentice, A G
1995-01-01
AIMS--To investigate the effects of interleukin (IL) 1, 2, 4, and 5 on the proliferation and survival of peripheral blood B cells from patients with B chronic lymphocytic leukaemia (B-CLL) and compare them with the effects on normal peripheral blood B cells. METHODS--The proliferation and survival of pokeweed mitogen (PWM) activated B cells from B-CLL (n = 12) and normal peripheral blood (n = 5) were studied in vitro in response to IL-1, IL-2 IL-4, and IL-5. Survival of cells in cultures with or without added interleukins was studied by microscopic examination of cells and DNA agarose gel electrophoresis. RESULTS--Proliferation was observed in both B-CLL and normal peripheral blood cells on culture with IL-2 alone and also in some, but not all, B-CLL and normal peripheral blood cells with IL-1 and IL-4. However, there was greater variability in B-CLL cell responses than in normal peripheral blood cells. Il-5 did not affect normal peripheral blood cell proliferation but it increased proliferation in two B-CLL cases. Synergistic effects of these cytokines were not detected. IL-4 inhibited normal peripheral blood and B-CLL cell proliferation after the addition of IL-2. Inhibition of B-CLL cell responses to IL-2 was also observed with IL-5 and Il-1. Survival of B-CLL cells in cultures was enhanced with IL-4 not by an increase in proliferation but by reduced apoptosis. No such effect was seen in normal peripheral blood cells. IL-2 had a less noticeable antiapoptotic effect; IL-5 enhanced apoptosis in B-CLL cells. CONCLUSIONS--B-CLL and normal peripheral blood cells proliferated equally well in response to IL-2. IL-4 had a much lower effect on B-CLL cell proliferation, but had noticeable antiapoptotic activity. IL-5 enhanced cell death by apoptosis. Images PMID:7629299
Atlantic salmon (Salmo salar) smolt production: the relative importance of survival and body growth
Horton, G.E.; Letcher, B.H.; Bailey, M.M.; Kinnison, M.T.
2009-01-01
The complex life history of Atlantic salmon (Salmo salar) coupled with interacting abiotic and biotic factors leads to extreme demographic variability across the species' range. Our goal was to evaluate the relative importance of survival and body growth in determining smolt production across space and time. We used passive integrated transponder tags and capture-mark-recapture analyses to estimate survival, emigration, and growth for six cohorts of presmolt Atlantic salmon in two streams (three cohorts per stream) in New England, USA. We observed remarkable among-cohort consistency in mean monthly survival during a 17-month period from age-0+ autumn to age-2+ spring yet high variability in monthly survival over shorter time intervals (seasons). Despite this latter variability, survival did not translate into amongcohort differences in proportions of age-2+ versus age-3+ smolts. Alternatively, the high variability across seasons and cohorts in mean individual growth rate did lead to differences in within-cohort proportions of age-2+ versus age-3+ smolts (regardless of stream). We conclude that in our two small study streams, variability in growth and size impacted smolt age and, ultimately, smolt production. Density-dependent effects on growth at the scale of the entire study site represent a possible mechanism underlying our observations.
Italian regional health system structure and expected cancer survival.
Vercelli, Marina; Lillini, Roberto; Quaglia, Alberto; Capocaccia, Riccardo
2014-01-01
Few studies deal with the association of socioeconomic and health system resource variables with cancer survival at the Italian regional level, where the greatest number of decisions about social and health policies and resource allocations are taken. The present study aimed to describe the causal relationships between socioeconomic and health system resource factors and regional cancer survival and to compute the expected cancer survival at provincial, regional and area levels. Age-standardized relative survival at 5 years from diagnosis of cases incident in 1995-1998 and followed up to 2004 were derived by gender for 11 sites from the Italian Association of Cancer Registries data bank. The socioeconomic and health system resource variables, describing at a regional level the macro-economy, demography, labor market, and health resources for 1995-2005, came from the Health for All database. A principal components factor analysis was applied to the socioeconomic and health system resource variables. For every site, linear regression models were computed considering the relative survival at 5 years as a dependent variable and the principal components factor analysis factors as independent variables. The factors described the socioeconomic and health-related features of the regional systems and were causally related to the characteristics of the patient taken in charge. The models built by the factors allowed computation of the expected relative survival at 5 years with very good concordance with those observed at regional, macro-regional and national levels. In the regions without any cancer registry, survival was coherent with that of neighboring regions with similar socioeconomic and health system resources characteristics. The models highlighted the causal correlations between socioeconomic and health system resources and cancer survival, suggesting that they could be good evaluation tools for the efficiency of the resources allocation and use.
Survival strategies of Bacillus spores in food.
Stecchini, Mara Lucia; Del Torre, Manuela; Polese, Pierluigi
2013-11-01
Control of bacterial spores is one of the major problem in the food preservation. Spores of Bacillus genus are commonly present in different environments, including soil and the gut of insects and animals and, as a result, they can be spread to all kind of foods. Due to their high resistance properties, their complete inactivation in food is often impossible without changing the product characteristics. Surviving spores can germinate and grow out to vegetative cells, with the consequent great risk of food spoilage and food poisoning after consumption. Spores have evolved various mechanisms, including phenotypic variability, to protect themselves from a wide range of damage resulting from food preservation treatments. Even if the phenotypic heterogeneity contributes to increase the chances of survival of Bacillus spore to conventional preservation treatments, in some specific instances, an homogeneous response could be the result of a strategy adopted by the spores to increase resistance to those treatments.
Polgarova, Kamila; Vargova, Karina; Kulvait, Vojtech; Dusilkova, Nina; Minarik, Lubomir; Zemanova, Zuzana; Pesta, Michal; Jonasova, Anna; Stopka, Tomas
2017-01-01
Azacitidine (AZA) for higher risk MDS patients is a standard therapy with limited durability. To monitor mutation dynamics during AZA therapy we utilized massive parallel sequencing of 54 genes previously associated with MDS/AML pathogenesis. Serial sampling before and during AZA therapy of 38 patients (reaching median overall survival 24 months (Mo) with 60% clinical responses) identified 116 somatic pathogenic variants with allele frequency (VAF) exceeding 5%. High accuracy of data was achieved via duplicate libraries from myeloid cells and T-cell controls. We observed that nearly half of the variants were stable while other variants were highly dynamic. Patients with marked decrease of allelic burden upon AZA therapy achieved clinical responses. In contrast, early-progressing patients on AZA displayed minimal changes of the mutation pattern. We modeled the VAF dynamics on AZA and utilized a joint model for the overall survival and response duration. While the presence of certain variants associated with clinical outcomes, such as the mutations of CDKN2A were adverse predictors while KDM6A mutations yield lower risk of dying, the data also indicate that allelic burden volatility represents additional important prognostic variable. In addition, preceding 5q- syndrome represents strong positive predictor of longer overall survival and response duration in high risk MDS patients treated with AZA. In conclusion, variants dynamics detected via serial sampling represents another parameter to consider when evaluating AZA efficacy and predicting outcome. PMID:29340104
Syal, Kirtimaan; Bhardwaj, Neerupma; Chatterji, Dipankar
2017-01-01
Earlier, vitamin C was demonstrated to sterilize Mycobacterium tuberculosis culture via Fenton's reaction at high concentration. It alters the regulatory pathways associated with stress response and dormancy. Since (p)ppGpp is considered to be the master regulator of stress response and is responsible for bacterial survival under stress, we tested the effect of vitamin C on the formation of (p)ppGpp. In vivo estimation of (p)ppGpp showed a decrease in (p)ppGpp levels in vitamin C-treated M. smegmatis cells in comparison to the untreated cells. Furthermore, in vitro (p)ppGpp synthesis using Rel MSM enzyme was conducted in order to confirm the specificity of the inhibition in the presence of variable concentrations of vitamin C. We observed that vitamin C at high concentration can inhibit the synthesis of (p)ppGpp. We illustrated binding of vitamin C to Rel MSM by isothermal titration calorimetry. Enzyme kinetics was followed where K 0.5 was found to be increased with the concomitant reduction of V max value suggesting mixed inhibition. Both long-term survival and biofilm formation were inhibited by vitamin C. The experiments suggest that vitamin C has the potential to be developed as the inhibitor of (p)ppGpp synthesis and stress response, at least in the concentration range used here. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Distiller, Larry A; Joffe, Barry I; Melville, Vanessa; Welman, Tania; Distiller, Greg B
2006-01-01
The factors responsible for premature coronary atherosclerosis in patients with type 1 diabetes are ill defined. We therefore assessed carotid intima-media complex thickness (IMT) in relatively long-surviving patients with type 1 diabetes as a marker of atherosclerosis and correlated this with traditional risk factors. Cross-sectional study of 148 patients with relatively long-surviving (>18 years) type 1 diabetes (76 men and 72 women) attending the Centre for Diabetes and Endocrinology, Johannesburg. The mean common carotid artery IMT and presence or absence of plaque was evaluated by high-resolution B-mode ultrasound. Their median age was 48 years and duration of diabetes 26 years (range 18-59 years). Traditional risk factors (age, duration of diabetes, glycemic control, hypertension, smoking and lipoprotein concentrations) were recorded. Three response variables were defined and modeled. Standard multiple regression was used for a continuous IMT variable, logistic regression for the presence/absence of plaque and ordinal logistic regression to model three categories of "risk." The median common carotid IMT was 0.62 mm (range 0.44-1.23 mm) with plaque detected in 28 cases. The multiple regression model found significant associations between IMT and current age (P=.001), duration of diabetes (P=.033), BMI (P=.008) and diagnosed hypertension (P=.046) with HDL showing a protective effect (P=.022). Current age (P=.001) and diagnosed hypertension (P=.004), smoking (P=.008) and retinopathy (P=.033) were significant in the logistic regression model. Current age was also significant in the ordinal logistic regression model (P<.001), as was total cholesterol/HDL ratio (P<.001) and mean HbA(1c) concentration (P=.073). The major factors influencing common carotid IMT in patients with relatively long-surviving type 1 diabetes are age, duration of diabetes, existing hypertension and HDL (protective) with a relatively minor role ascribed to relatively long-standing glycemic control.
Feedback-driven response to multidecadal climatic variability at an alpine treeline
Alftine, K.J.; Malanson, G.P.; Fagre, D.B.
2003-01-01
The Pacific Decadal Oscillation (PDO) has significant climatological and ecological effects in northwestern North America. Its possible effects and their modification by feedbacks are examined in the forest-tundra ecotone in Glacier National Park, Montana, USA. Tree ring samples were collected to estimate establishment dates in 10 quadrats. Age-diameter regressions were used to estimate the ages of uncored trees. The temporal pattern of establishment and survival was compared to the pattern of the PDO. A wave of establishment began in the mid-1940s, rose to a peak rate in the mid-1970s, and dropped precipitously beginning ca. 1980 to near zero for the 1990s. The period of establishment primarily coincided with the negative phase of the PDO, but the establishment and survival pattern is not correlated with the PDO index. The pattern indicates a period during which establishment was possible and was augmented by positive feedback from surviving trees. Snow may be the most important factor in the feedback, but studies indicate that its effects vary locally. Spatially differentiated analyses of decadal or longer periodicity may elucidate responses to climatic variation. ?? 2003 by V. H. Winston and Son, Inc. All rights reserved.
Tissue Platinum Concentration and Tumor Response in Non–Small-Cell Lung Cancer
Kim, Eric S.; Lee, J. Jack; He, Guangan; Chow, Chi-Wan; Fujimoto, Junya; Kalhor, Neda; Swisher, Stephen G.; Wistuba, Ignacio I.; Stewart, David J.; Siddik, Zahid H.
2012-01-01
Purpose Platinum resistance is a major limitation in the treatment of advanced non–small-cell lung cancer (NSCLC). Reduced intracellular drug accumulation is one of the most consistently identified features of platinum-resistant cell lines, but clinical data are limited. We assessed the effects of tissue platinum concentrations on response and survival in NSCLC. Patients and Methods We measured total platinum concentrations by flameless atomic absorption spectrophotometry in 44 archived fresh-frozen NSCLC specimens from patients who underwent surgical resection after neoadjuvant platinum-based chemotherapy. Tissue platinum concentration was correlated with percent reduction in tumor size on post- versus prechemotherapy computed tomography scans. The relationship between tissue platinum concentration and survival was assessed by univariate and multicovariate Cox proportional hazards regression model analysis and Kaplan-Meier analysis. Results Tissue platinum concentration correlated significantly with percent reduction in tumor size (P < .001). The same correlations were seen with cisplatin, carboplatin, and all histology subgroups. Furthermore, there was no significant impact of potential variables such as number of cycles and time lapse from last chemotherapy on platinum concentration. Patients with higher platinum concentration had longer time to recurrence (P = .034), progression-free survival (P = .018), and overall survival (P = .005) in the multicovariate Cox model analysis after adjusting for number of cycles. Conclusion This clinical study established a relationship between tissue platinum concentration and response in NSCLC. It suggests that reduced platinum accumulation might be an important mechanism of platinum resistance in the clinical setting. Further studies investigating factors that modulate intracellular platinum concentration are warranted. PMID:22891266
Coupling suitable prey field to in situ fish larval condition and abundance in a subtropical estuary
NASA Astrophysics Data System (ADS)
Machado, Irene; Calliari, Danilo; Denicola, Ana; Rodríguez-Graña, Laura
2017-03-01
Survival of fish larvae is influenced by the suitability of the prey field and its variability in time and space. Relationships among food quality, quantity and recruitment have been explored in temperate ecosystems where spawning and secondary production are strongly seasonal, but for subtropical estuaries the mechanisms responsible for larval survival remain poorly identified. This study evaluated the nutritional condition (feeding incidence and AARS activity) and abundance of a multi-specific assemblage of fish larvae from a subtropical estuary in South America (Solís Grande, Uruguay) during the fish reproductive season; and related both variables to prey abundance, composition, size and fatty acids content. The larval assemblage was composed of 13 species belonging to different functional groups and composition varied seasonally. Contrary to expectations larval condition did not match an increase in prey quality. Food availability was high throughout the study period, although significant changes existed in the size and taxonomic structure of the prey assemblage. The temporal succession of complementary factors - temperature, prey composition, abundance and quality - promoted a wide window of opportunity for larvae, where quality seemed to have compensated quantity. Such combination of factors could allow an extended larval survival along the spawning season. These findings underline the importance of a better understanding of subtropical estuaries as nursery areas.
2012-01-01
Background We explore the benefits of applying a new proportional hazard model to analyze survival of breast cancer patients. As a parametric model, the hypertabastic survival model offers a closer fit to experimental data than Cox regression, and furthermore provides explicit survival and hazard functions which can be used as additional tools in the survival analysis. In addition, one of our main concerns is utilization of multiple gene expression variables. Our analysis treats the important issue of interaction of different gene signatures in the survival analysis. Methods The hypertabastic proportional hazards model was applied in survival analysis of breast cancer patients. This model was compared, using statistical measures of goodness of fit, with models based on the semi-parametric Cox proportional hazards model and the parametric log-logistic and Weibull models. The explicit functions for hazard and survival were then used to analyze the dynamic behavior of hazard and survival functions. Results The hypertabastic model provided the best fit among all the models considered. Use of multiple gene expression variables also provided a considerable improvement in the goodness of fit of the model, as compared to use of only one. By utilizing the explicit survival and hazard functions provided by the model, we were able to determine the magnitude of the maximum rate of increase in hazard, and the maximum rate of decrease in survival, as well as the times when these occurred. We explore the influence of each gene expression variable on these extrema. Furthermore, in the cases of continuous gene expression variables, represented by a measure of correlation, we were able to investigate the dynamics with respect to changes in gene expression. Conclusions We observed that use of three different gene signatures in the model provided a greater combined effect and allowed us to assess the relative importance of each in determination of outcome in this data set. These results point to the potential to combine gene signatures to a greater effect in cases where each gene signature represents some distinct aspect of the cancer biology. Furthermore we conclude that the hypertabastic survival models can be an effective survival analysis tool for breast cancer patients. PMID:23241496
Variable selection in discrete survival models including heterogeneity.
Groll, Andreas; Tutz, Gerhard
2017-04-01
Several variable selection procedures are available for continuous time-to-event data. However, if time is measured in a discrete way and therefore many ties occur models for continuous time are inadequate. We propose penalized likelihood methods that perform efficient variable selection in discrete survival modeling with explicit modeling of the heterogeneity in the population. The method is based on a combination of ridge and lasso type penalties that are tailored to the case of discrete survival. The performance is studied in simulation studies and an application to the birth of the first child.
Francis, Jasmine H; Iyer, Saipriya; Gobin, Y Pierre; Brodie, Scott E; Abramson, David H
2017-10-01
To compare the efficacy and toxicity of treating class 3 retinoblastoma vitreous seeds with ophthalmic artery chemosurgery (OAC) alone versus OAC with intravitreous chemotherapy. Retrospective cohort study. Forty eyes containing clouds (class 3 vitreous seeds) of 40 retinoblastoma patients (19 treated with OAC alone and 21 treated with OAC plus intravitreous and periocular chemotherapy). Ocular survival, disease-free survival and time to regression of seeds were estimated with Kaplan-Meier estimates. Ocular toxicity was evaluated by clinical findings and electroretinography: 30-Hz flicker responses were compared at baseline and last follow-up visit. Continuous variables were compared with Student t test, and categorical variables were compared with the Fisher exact test. Ocular survival, disease-free survival, and time to regression of seeds. There were no disease- or treatment-related deaths and no patient demonstrated externalization of tumor or metastatic disease. There was no significant difference in the age, laterality, disease, or disease status (treatment naïve vs. previously treated) between the 2 groups. The time to regression of seeds was significantly shorter for eyes treated with OAC plus intravitreous chemotherapy (5.7 months) compared with eyes treated with OAC alone (14.6 months; P < 0.001). The 18-month Kaplan-Meier estimates of disease-free survival were significantly worse for the OAC alone group: 67.1% (95% confidence interval, 40.9%-83.6%) versus 94.1% (95% confidence interval, 65%-99.1%) for the OAC plus intravitreous chemotherapy group (P = 0.05). The 36-month Kaplan-Meier estimates of ocular survival were 83.3% (95% confidence interval, 56.7%-94.3%) for the OAC alone group and 100% for the OAC plus intravitreous chemotherapy group (P = 0.16). The mean change in electroretinography responses was not significantly different between groups, decreasing by 11 μV for the OAC alone group and 22 μV for the OAC plus intravitreous chemotherapy group (P = 0.4). Treating vitreous seed clouds with OAC and intravitreous and periocular chemotherapy, compared with OAC alone, resulted in a shorter time to regression and was associated with fewer recurrences requiring additional treatment and fewer enucleations. The toxicity to the retina does not seem to be significantly worse in the OAC plus intravitreous chemotherapy group. Copyright © 2017 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
Nemelc, R M; Stadhouder, A; van Royen, B J; Jiya, T U
2014-11-01
Purpose: To evaluate outcome and survival and to identify prognostic variables for patients surgically treated for spinal metastases. Methods: A retrospective study was performed on 86 patients, surgically treated for spinal metastases. Preoperative analyses of the ASIA and spinal instability neoplastic scores (SINS) were performed. Survival curves of different prognostic variables were made by Kaplan–Meier analysis and the variables entered in a Cox proportional hazards model to determine their significance on survival. The correlation between preoperative radiotherapy and postoperative wound infections was also evaluated. Results: Survival analysis was performed on 81 patients,37 women and 44 men. Five patients were excluded due to missing data. Median overall survival was 38 weeks [95 % confidence interval (CI) 27.5–48.5 weeks], with a 3-month survival rate of 81.5 %. Breast tumor had the best median survival of 127 weeks and lung tumor the worst survival of 18 weeks. Univariate analysis showed tumor type, preoperative ASIA score (p = 0.01) and visceral metastases(p = 0.18) were significant prognostic variables for survival.Colon tumors had 5.53 times hazard ratio compared to patients with breast tumor. ASIA-C score had more than 13.03 times the hazard ratio compared to patients with an ASIA-E score. Retrospective analysis of the SINS scores showed 34 patients with a score of 13–18 points, 44 patients with a score of 7–12 points, and 1 patient with a score of 6 points. Preoperative radiotherapy had no influence on the postoperative incidence of deep surgical wound infections (p = 0.37). Patients with spinal metastases had a median survival of 38 weeks postoperative. The primary tumor type and ASIA score were significant prognostic factors for survival. Preoperative radiotherapy neither had influence on survival nor did it constitute a risk for postoperative surgical wound infections.
Quantifying the Variability in Species' Vulnerability to Ocean Acidification
NASA Astrophysics Data System (ADS)
Kroeker, K. J.; Kordas, R. L.; Crim, R.; Gattuso, J.; Hendriks, I.; Singh, G. G.
2012-12-01
Ocean acidification represents a threat to marine species and ecosystems worldwide. As such, understanding the potential ecological impacts of acidification is a high priority for science, management, and policy. As research on the biological impacts of ocean acidification continues to expand at an exponential rate, a comprehensive understanding of the generalities and/or variability in organisms' responses and the corresponding levels of certainty of these potential responses is essential. Meta-analysis is a quantitative technique for summarizing the results of primary research studies and provides a transparent method to examine the generalities and/or variability in scientific results across numerous studies. Here, we perform the most comprehensive meta-analysis to date by synthesizing the results of 228 studies examining the biological impacts of ocean acidification. Our results reveal decreased survival, calcification, growth, reproduction and development in response to acidification across a broad range of marine organisms, as well as significant trait-mediated variation among taxonomic groups and enhanced sensitivity among early life history stages. In addition, our results reveal a pronounced sensitivity of molluscs to acidification, especially among the larval stages, and enhanced vulnerability to acidification with concurrent exposure to increased seawater temperatures across a diversity of organisms.
Bertolde, Fabiana Zanelato; De Almeida, Alex-Alan Furtado; Corrêa, Ronan Xavier; Gomes, Fábio Pinto; Gaiotto, Fernanda Amato; Baligar, Virupax C; Loguercio, Leandro Lopes
2010-01-01
In soil, anoxia conditions generated by waterlogging induce changes in genetic, morphological and physiological processes, altering the growth and development of plants. Mass propagation of cacao (Theobroma cacao L.) plantlets (clones) is affected by waterlogging caused by heavy rains and irrigation methods used to induce rooting. An experiment was undertaken to assess the effects of a 45-day flooding (anoxia) on physiological and morphological traits of 35 elite cacao genotypes, aiming at potentially identifying those with greater tolerance to flooding of the growth substrate. Eighteen fluorochrome-labeled microsatellite (SSR) primer pairs were used to assess genetic variability among clones, with 248 alleles being amplified and used to calculate similarity coefficients. The resulting dendrogram indicated the presence of four major groups, in which two represented 60% and 31% of the genotypes tested. A general trend toward high levels of heterozygosity was also found for physiological and morphological traits. The survival index (IS) for flood tolerance observed varied from 30 to 96%. Clones TSA-654, TSA-656, TSA-792, CA-1.4, CEPEC-2009 and PH-17 showed an IS value above 94%, whereas CEPEC-2010, CEPEC-2002, CA-7.1 and VB-903 clones were those mostly affected by waterlogging, with IS value below 56%. All genotypes displayed lenticel and adventitious root formation in response to waterlogging, although with different intensities. To determine whether patterns of physiological response could be associated with tolerance to anoxia, a similarity-grouping analysis was performed using the ratio between waterlogged and control values obtained for a series of physiological variables assessed. No specific pattern of physiological and morphological responses to waterlogging was strictly associated with survival of plantlets. However, results revealed by the dendrogram suggest that absence of leaf chlorosis may be a proper trait to indicate cacao clones with higher survival rates under flooding conditions. Consequences of these findings are discussed in the context of developing improved strategies for mass production of clones from elite cacao genotypes.
Drennan, Ian R; Strum, Ryan P; Byers, Adam; Buick, Jason E; Lin, Steve; Cheskes, Sheldon; Hu, Samantha; Morrison, Laurie J
2016-04-05
The increasing number of people living in high-rise buildings presents unique challenges to care and may cause delays for 911-initiated first responders (including paramedics and fire department personnel) responding to calls for out-of-hospital cardiac arrest. We examined the relation between floor of patient contact and survival after cardiac arrest in residential buildings. We conducted a retrospective observational study using data from the Toronto Regional RescuNet Epistry database for the period January 2007 to December 2012. We included all adult patients (≥ 18 yr) with out-of-hospital cardiac arrest of no obvious cause who were treated in private residences. We excluded cardiac arrests witnessed by 911-initiated first responders and those with an obvious cause. We used multivariable logistic regression to determine the effect on survival of the floor of patient contact, with adjustment for standard Utstein variables. During the study period, 7842 cases of out-of-hospital cardiac arrest met the inclusion criteria, of which 5998 (76.5%) occurred below the third floor and 1844 (23.5%) occurred on the third floor or higher. Survival was greater on the lower floors (4.2% v. 2.6%, p = 0.002). Lower adjusted survival to hospital discharge was independently associated with higher floor of patient contact, older age, male sex and longer 911 response time. In an analysis by floor, survival was 0.9% above floor 16 (i.e., below the 1% threshold for futility), and there were no survivors above the 25th floor. In high-rise buildings, the survival rate after out-of-hospital cardiac arrest was lower for patients residing on higher floors. Interventions aimed at shortening response times to treatment of cardiac arrest in high-rise buildings may increase survival. © 2016 Canadian Medical Association or its licensors.
Merckx, Thomas; Serruys, Mélanie; Van Dyck, Hans
2015-01-01
Recent anthropogenic eutrophication has meant that host plants of nettle-feeding insects became quasi-omnipresent in fertile regions of Western Europe. However, host plant resource quality – in terms of microclimate and nutritional value – may vary considerably between the ‘original’ forest habitat and ‘recent’ agricultural habitat. Here, we compared development in both environmental settings using a split-brood design, so as to explore to what extent larval survival and adult morphology in the nettle-feeding butterfly Aglais urticae are influenced by the anthropogenic environment. Nettles along field margins had higher C/N ratios and provided warmer microclimates to larvae. Larvae developed 20% faster and tended to improve their survival rates, on the agricultural land compared to woodland. Our split-brood approach indicated plastic responses within families, but also family effects in the phenotypic responses. Adult males and females had darker wing pigmentation in the drier and warmer agricultural environment, which contrasts with the thermal melanism hypothesis. Developmental plasticity in response to this microclimatically different and more variable habitat was associated with a broader phenotypic parameter space for the species. Both habitat expansion and developmental plasticity are likely contributors to the ecological and evolutionary success of these nettle-feeding insects in anthropogenic environments under high nitrogen load. PMID:25926881
Vishnubalaji, Radhakrishnan; Manikandan, Muthurangan; Fahad, Mohamed; Hamam, Rimi; Alfayez, Musaad; Kassem, Moustapha; Aldahmash, Abdullah; Alajez, Nehad M
2018-03-02
Tumour heterogeneity leads to variable clinical response and inaccurate diagnostic and prognostic assessment. Cancer stem cells (CSCs) represent a subpopulation responsible for invasion, metastasis, therapeutic resistance, and recurrence in many human cancer types. However, the true identity of colorectal cancer (CRC) SCs remains elusive. Here, we aimed to characterize and define the gene expression portrait of CSCs in CRC-model SW403 cells. We found that ALDH + positive cells are clonogenic and highly proliferative; their global gene expression profiling-based molecular signature revealed gene enrichment related to DNA damage, MAPK, FAK, oxidative stress response, and Wnt signalling. ALDH + cells showed enhanced ROS stress resistance, whereas MAPK/FAK pathway pharmacologic inhibition limited their survival. Conversely, 5-fluorouracil increased the ALDH + cell fraction among the SW403, HCT116 and SW620 CRC models. Notably, analysis of ALDH1A1 and POU5F1 expression levels in cohorts of 462 or 420 patients for overall (OS) or disease-free (DFS) survival, respectively, obtained from the Cancer Genome Atlas CRC dataset, revealed strong association between elevated expression and poor OS ( p = 0.006) and poor DFS ( p = 0.05), thus implicating ALDH1A1 and POU5F1 in CRC prognosis. Our data reveal distinct molecular signature of ALDH + CSCs in CRC and suggest pathways relevant for successful targeted therapies and management of CRC.
2011-01-01
Introduction Microtubule associated proteins (MAPs) endogenously regulate microtubule stabilization and have been reported as prognostic and predictive markers for taxane response. The microtubule stabilizer, MAP-tau, has shown conflicting results. We quantitatively assessed MAP-tau expression in two independent breast cancer cohorts to determine prognostic and predictive value of this biomarker. Methods MAP-tau expression was evaluated in the retrospective Yale University breast cancer cohort (n = 651) using tissue microarrays and also in the TAX 307 cohort, a clinical trial randomized for TAC versus FAC chemotherapy (n = 140), using conventional whole tissue sections. Expression was measured using the AQUA method for quantitative immunofluorescence. Scores were correlated with clinicopathologic variables, survival, and response to therapy. Results Assessment of the Yale cohort using Cox univariate analysis indicated an improved overall survival (OS) in tumors with a positive correlation between high MAP-tau expression and overall survival (OS) (HR = 0.691, 95% CI = 0.489-0.974; P = 0.004). Kaplan Meier analysis showed 10-year survival for 65% of patients with high MAP-tau expression compared to 52% with low expression (P = .006). In TAX 307, high expression was associated with significantly longer median time to tumor progression (TTP) regardless of treatment arm (33.0 versus 23.4 months, P = 0.010) with mean TTP of 31.2 months. Response rates did not differ by MAP-tau expression (P = 0.518) or by treatment arm (P = 0.584). Conclusions Quantitative measurement of MAP-tau expression has prognostic value in both cohorts, with high expression associated with longer TTP and OS. Differences by treatment arm or response rate in low versus high MAP-tau groups were not observed, indicating that MAP-tau is not associated with response to taxanes and is not a useful predictive marker for taxane-based chemotherapy. PMID:21888627
Sodhi, Kanwalpreet; Singla, Manender Kumar; Shrivastava, Anupam
2015-02-01
Despite advances in cardiopulmonary resuscitation and widespread life-support trainings, the outcomes of resuscitation are variable. There is a definitive need for organizational inputs to strengthen the resuscitation process. Our hospital authorities introduced certain changes at the organizational level in our in-house resuscitation protocol. We aimed to study the impact of these changes on the outcomes of resuscitation. The hospital code blue committee decided to reformulate the resuscitation protocols and reframe the code blue team. Various initiatives were taken in the form of infrastructural changes, procurement of equipment, organising certified training programs, conduct of mock code and simulation drills etc. A prospective and retrospective observational study was made over 6 years: a pre-intervention period, which included all cardiac arrests from January 2007 to December 2009, before the implementation of the program, and a post-intervention period from January 2010 to December 2012, after the implementation of the program. The outcomes of interest were response time, immediate survival, day/night survival and survival to discharge ratio. 2,164 in-hospital cardiac arrests were included in the study, 1,042 during the pre-intervention period and 1,122 during the post-intervention period. The survival percentage increased from 26.7 to 40.8 % (p < 0.05), and the survival to discharge ratio increased from 23.4 to 66.6 % (p < 0.05). Both day- and night-time survival improved (p < 0.05) and response time improved from 4 to 1.5 min. A strong hospital-based resuscitation policy with well-defined protocols and infrastructure has potential synergistic effect and plays a big role in improving the outcomes of resuscitation.
Romano, Francesco Jacopo; Guadagno, Elia; Solari, Domenico; Borrelli, Giorgio; Pignatiello, Sara; Cappabianca, Paolo; Del Basso De Caro, Marialaura
2018-06-01
Glioblastoma is one of the most malignant cancers, with a distinguishing dismal prognosis: surgery followed by chemo- and radiotherapy represents the current standard of care, and chemo- and radioresistance underlie disease recurrence and short overall survival of patients suffering from this malignancy. ATM is a kinase activated by autophosphorylation upon DNA doublestrand breaks arising from errors during replication, byproducts of metabolism, chemotherapy or ionizing radiations; TP53 is one of the most popular tumor suppressor, with a preeminent role in DNA damage response and repair. To study the effects of the immunohistochemical expression of p-ATM and p53 in glioblastoma patients, 21 cases were retrospectively examined. In normal brain tissue, p-ATM was expressed only in neurons; conversely, in tumors cells, the protein showed a variable cytoplasmic expression (score: +,++,+++), with being completely undetectable in three cases. Statistical analysis revealed that high p-ATM score (++/+++) strongly correlated to shorter survival (P = 0.022). No difference in overall survival was registered between p53 normally expressed (NE) and overexpressed (OE) glioblastoma patients (P = 0.669). Survival analysis performed on the results from combined assessment of the two proteins showed that patients with NE p53 /low pATM score had longer overall survival than the NE p53/ high pATM score counterpart. Cox-regression analysis confirmed this finding (HR = 0.025; CI 95% = 0.002-0.284; P = 0.003). Our study outlined the immunohistochemical expression of p-ATM/p53 in glioblastomas and provided data on their possible prognostic/predictive of response role. A "non-oncogene addiction" to ATM for NEp53 glioblastoma could be postulated, strengthening the rationale for development of ATM inhibiting drugs. © 2018 Wiley Periodicals, Inc.
Shin, Su-Jin; Jeon, Yoon Kyung; Cho, Yong Mee; Lee, Jae-Lyun; Chung, Doo Hyun; Park, Ji Young
2015-01-01
Background. Vascular endothelial growth factor pathway (VEGF)-tyrosine kinase inhibitors (TKIs) are used as the first-line treatment for patients with metastatic clear cell renal cell carcinoma (mCCRCC). Recently, programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) blockade emerged as promising therapy for renal cell carcinoma. However, the expression pattern and prognostic implication of programmed death-ligands (PD-Ls) in mCCRCC patients receiving VEGF-TKI remain unclear. Patients and Methods. PD-L1 and PD-L2 expression in tumor cells and the quantities of PD-1+ tumor-infiltrating lymphocytes were immunohistochemically evaluated in 91 mCCRCC patients treated with VEGF-TKI, and their associations with VEGF-TKI responsiveness and clinical outcome were analyzed. Results. PD-L1 immunopositivity was observed in 17.6% and significantly associated with a high International Society of Urological Pathology grade (p = .031) and sarcomatoid features (p = .014). PD-L2 immunopositivity was observed in 39.6% and was not associated with any of the assessed clinicopathological variables. PD-L1-positive cases showed poor VEGF-TKI responsiveness (p = .012) compared with PD-L1-negative cases. In univariate survival analysis, PD-L1 immunopositivity was significantly associated with shorter overall survival (OS) (p = .037) and progression-free survival (PFS) (p = .043). Multivariate survival analysis revealed that PD-L1 expression was independently associated with poor OS (p = .038) and PFS (p = .013) in addition to tumor necrosis (p = .006; p = .029, respectively) and Memorial Sloan Kettering Cancer Center score (p = .018; p = .032, respectively). PD-L2 expression was neither associated with VEGF-TKI responsiveness nor patients’ outcome. Conclusion. PD-L1 expression was significantly related to lack of VEGF-TKI responsiveness and independently associated with shorter survival in mCCRCC patients after VEGF-TKI treatment. PD-L1 may have a predictive and prognostic value for determining the value of VEGF-TKI treatment in patients with mCCRCC. Implications for Practice: Vascular endothelial growth factor pathway (VEGF)-tyrosine kinase inhibitors (TKIs) are essential for the treatment of metastatic renal cell carcinoma patients, but the treatment suffers from a lack of predictive markers. This study demonstrates that PD-L1 expression is a predictor for unfavorable response to VEGF-TKI and a prognostic indicator for poor overall survival and progression-free survival in patients with metastatic clear cell renal cell carcinoma receiving VEGF-TKI. PMID:26424759
New cohort growth and survival in variable retention harvests of a pine ecosystem in Minnesota, USA
Rebecca A. Montgomery; Brian J. Palik; Suzanne B. Boyden; Peter B. Reich
2013-01-01
There is significant interest in silvicultural systems such as variable retention harvesting (VRH) that emulate natural disturbance and increase structural complexity, spatial heterogeneity, and biological diversity in managed forests. However, the consequences of variable retention harvesting for new cohort growth and survival are not well characterized in many forest...
Low Survival Rates of Oral and Oropharyngeal Squamous Cell Carcinoma
da Silva Júnior, Francisco Feliciano; dos Santos, Karine de Cássia Batista; Ferreira, Stefania Jeronimo
2017-01-01
Aim To assess the epidemiological and clinical factors that influence the prognosis of oral and oropharyngeal squamous cell carcinoma (SCC). Methods One hundred and twenty-one cases of oral and oropharyngeal SCC were selected. The survival curves for each variable were estimated using the Kaplan-Meier method. The Cox regression model was applied to assess the effect of the variables on survival. Results Cancers at an advanced stage were observed in 103 patients (85.1%). Cancers on the tongue were more frequent (23.1%). The survival analysis was 59.9% in one year, 40.7% in two years, and 27.8% in 5 years. There was a significant low survival rate linked to alcohol intake (p = 0.038), advanced cancer staging (p = 0.003), and procedures without surgery (p < 0.001). When these variables were included in the Cox regression model only surgery procedures (p = 0.005) demonstrated a significant effect on survival. Conclusion The findings suggest that patients who underwent surgery had a greater survival rate compared with those that did not. The low survival rates and the high percentage of patients diagnosed at advanced stages demonstrate that oral and oropharyngeal cancer patients should receive more attention. PMID:28638410
Individual Differences in Well-Being in Older Breast Cancer Survivors
Perkins, Elizabeth A.; Small, Brent J.; Balducci, Lodovico; Extermann, Martine; Robb, Claire; Haley, William E.
2007-01-01
Older women who survive breast cancer may differ significantly in their long-term well-being. Using a risk and protective factors model, we studied predictors of well-being in 127 women age 70 and above with a history of at least one year's survival of breast cancer. Mean post-cancer survivorship was 5.1 years. Using life satisfaction, depression and general health perceptions as outcome variables, we assessed whether demographic variables, cancer-related variables, health status and psychosocial resources predicted variability in well-being using correlational and hierarchical regression analyses. Higher age predicted increased depression but was not associated with life satisfaction or general health perceptions. Cancer-related variables, including duration of survival, and type of cancer treatment, were not significantly associated with survivors' well-being. Poorer health status was associated with poorer well-being in all three dependent variables. After controlling for demographics, cancer-related variables, and health status, higher levels of psychosocial resources including optimism, mastery, spirituality and social support predicted better outcome in all three dependent variables. While many older women survive breast cancer without severe sequelae, there is considerable variability in their well-being after survivorship. Successful intervention with older breast cancer survivors might include greater attention not only to cancer-specific concerns, but also attention to geriatric syndromes and functional impairment, and enhancement of protective psychosocial resources. PMID:17240157
Wieder, Robert; Shafiq, Basit; Adam, Nabil
2016-01-01
BACKGROUND: African American race negatively impacts survival from localized breast cancer but co-variable factors confound the impact. METHODS: Data sets were analyzed from the Surveillance, Epidemiology and End Results (SEER) directories from 1973 to 2011 consisting of patients with designated diagnosis of breast adenocarcinoma, race as White or Caucasian, Black or African American, Asian, American Indian or Alaskan Native, Native Hawaiian or Pacific Islander, age, stage I, II or III, grade 1, 2 or 3, estrogen receptor or progesterone receptor positive or negative, marital status as single, married, separated, divorced or widowed and laterality as right or left. The Cox Proportional Hazards Regression model was used to determine hazard ratios for survival. Chi square test was applied to determine the interdependence of variables found significant in the multivariable Cox Proportional Hazards Regression analysis. Cells with stratified data of patients with identical characteristics except African American or Caucasian race were compared. RESULTS: Age, stage, grade, ER and PR status and marital status significantly co-varied with race and with each other. Stratifications by single co-variables demonstrated worse hazard ratios for survival for African Americans. Stratification by three and four co-variables demonstrated worse hazard ratios for survival for African Americans in most subgroupings with sufficient numbers of values. Differences in some subgroupings containing poor prognostic co-variables did not reach significance, suggesting that race effects may be partly overcome by additional poor prognostic indicators. CONCLUSIONS: African American race is a poor prognostic indicator for survival from breast cancer independent of 6 associated co-variables with prognostic significance. PMID:27698895
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fairchild, Alysa; Goh, Philiz; Sinclair, Emily
2008-03-01
Purpose: Eleven randomized controlled trials (RCT) comparing various radiotherapy (RT) schedules for locally advanced lung cancer published since 1991 found no difference in palliation of intrathoracic symptoms. The most commonly prescribed schedule by Canadian Radiation Oncologists (RO) (20 Gy in five fractions [20 Gy/5]), when first evaluated versus 10 Gy/1 in a 2002 RCT, showed a significant survival benefit. A subsequent RCT assessing 20 Gy/5 found worse survival versus 16 Gy/2. This study examines whether the RT prescription for lung cancer palliation in the Rapid Response Radiotherapy Program (RRRP) has changed over time. Methods and Materials: Chart review was conductedmore » for patients treated with palliative thoracic RT across three periods (1999-2006). Patient demographics, tumor, treatment, and organizational factors were analyzed descriptively. Chi-square test was used to detect differences in proportions between unordered categorical variables. Continuous variables were tested using analysis of variance. Multivariate logistic regression was used to identify independent predictors of RT schedule prescribed. Results: A total of 117 patients received 121 courses of palliative thoracic RT. The most common dose (20 Gy/5) comprised 65% of courses in 1999, 68% in 2003, and 60% in 2005-2006 (p = 0.76). The next most common dose was 30 Gy/10 (13%). Overall, the median survival was 14.9 months, independent of RT schedule (p = 0.68). Multivariate analysis indicated palliative chemotherapy and certification year of RO were significant predictors of prescription of 20 Gy/5. Conclusion: RT schedule for palliation of intrathoracic symptoms did not mirror the results of sequential, conflicting RCTs, suggesting that factors other than the literature influenced practice patterns in palliative thoracic RT.« less
Variability in urban soils influences the health and growth of native tree seedlings
Clara C. Pregitzer; Nancy F. Sonti; Richard A. Hallett
2016-01-01
Reforesting degraded urban landscapes is important due to the many benefits urban forests provide. Urban soils are highly variable, yet little is known about how this variability in urban soils influences tree seedling performance and survival. We conducted a greenhouse study to assess health, growth, and survival of four native tree species growing in native glacial...
Wensveen, Felix M; van Gisbergen, Klaas P J M; Eldering, Eric
2012-09-01
Lymphocyte activation via the antigen receptor is associated with radical shifts in metabolism and changes in requirements for nutrients and cytokines. Concomitantly, drastic changes occur in the expression of pro-and anti-apoptotic proteins that alter the sensitivity of lymphocytes to limiting concentrations of key survival factors. Antigen affinity is a primary determinant for the capacity of activated lymphocytes to access these vital resources. The shift in metabolic needs and the variable access to key survival factors is used by the immune system to eliminate activated low-affinity cells and to generate an optimal high-affinity response. In this review, we focus on the control of apoptosis regulators in activated lymphocytes by nutrients, cytokines, and costimulation. We propose that the struggle among individual clones that leads to the formation of high-affinity effector cell populations is in effect an 'invisible' fourth signal required for effective immune responses. © 2012 John Wiley & Sons A/S.
Krzyzanowski, Michelle C.; Wood, Jordan F.; Brueggemann, Chantal; Bowitch, Alexander; Bethke, Mary; L’Etoile, Noelle D.; Ferkey, Denise M.
2016-01-01
All animals rely on their ability to sense and respond to their environment to survive. However, the suitability of a behavioral response is context-dependent, and must reflect both an animal’s life history and its present internal state. Based on the integration of these variables, an animal’s needs can be prioritized to optimize survival strategies. Nociceptive sensory systems detect harmful stimuli and allow for the initiation of protective behavioral responses. The polymodal ASH sensory neurons are the primary nociceptors in C. elegans. We show here that the guanylyl cyclase ODR-1 functions non-cell-autonomously to downregulate ASH-mediated aversive behaviors and that ectopic cGMP generation in ASH is sufficient to dampen ASH sensitivity. We define a gap junction neural network that regulates nociception and propose that decentralized regulation of ASH signaling can allow for rapid correlation between an animal’s internal state and its behavioral output, lending modulatory flexibility to this hard-wired nociceptive neural circuit. PMID:27459302
Krzyzanowski, Michelle C; Woldemariam, Sarah; Wood, Jordan F; Chaubey, Aditi H; Brueggemann, Chantal; Bowitch, Alexander; Bethke, Mary; L'Etoile, Noelle D; Ferkey, Denise M
2016-07-01
All animals rely on their ability to sense and respond to their environment to survive. However, the suitability of a behavioral response is context-dependent, and must reflect both an animal's life history and its present internal state. Based on the integration of these variables, an animal's needs can be prioritized to optimize survival strategies. Nociceptive sensory systems detect harmful stimuli and allow for the initiation of protective behavioral responses. The polymodal ASH sensory neurons are the primary nociceptors in C. elegans. We show here that the guanylyl cyclase ODR-1 functions non-cell-autonomously to downregulate ASH-mediated aversive behaviors and that ectopic cGMP generation in ASH is sufficient to dampen ASH sensitivity. We define a gap junction neural network that regulates nociception and propose that decentralized regulation of ASH signaling can allow for rapid correlation between an animal's internal state and its behavioral output, lending modulatory flexibility to this hard-wired nociceptive neural circuit.
Comonotonic bounds on the survival probabilities in the Lee-Carter model for mortality projection
NASA Astrophysics Data System (ADS)
Denuit, Michel; Dhaene, Jan
2007-06-01
In the Lee-Carter framework, future survival probabilities are random variables with an intricate distribution function. In large homogeneous portfolios of life annuities, value-at-risk or conditional tail expectation of the total yearly payout of the company are approximately equal to the corresponding quantities involving random survival probabilities. This paper aims to derive some bounds in the increasing convex (or stop-loss) sense on these random survival probabilities. These bounds are obtained with the help of comonotonic upper and lower bounds on sums of correlated random variables.
Season-dependent and independent responses of Mediterranean scrub to light conditions.
Zunzunegui, María; Díaz-Barradas, Mari Cruz; Jáuregui, Juan; Rodríguez, Herminia; Álvarez-Cansino, Leonor
2016-05-01
Semi-arid plant species cope with excess of solar radiation with morphological and physiological adaptations that assure their survival when other abiotic stressors interact. At the leaf level, sun and shade plants may differ in the set of traits that regulate environmental stressors. Here, we evaluated if leaf-level physiological seasonal response of Mediterranean scrub species (Myrtus communis, Halimium halimifolium, Rosmarinus officinalis, and Cistus salvifolius) depended on light availability conditions. We aimed to determine which of these responses prevailed independently of the marked seasonality of Mediterranean climate, to define a leaf-level strategy in the scrub community. Thirty six leaf response variables - involving gas exchange, water status, photosystem II photochemical efficiency, photosynthetic pigments and leaf structure - were seasonally measured in sun exposed and shaded plants under field conditions. Physiological responses showed a common pattern throughout the year, in spite of the marked seasonality of the Mediterranean climate and of species-specific differences in the response to light intensity. Variables related to light use, CO2 assimilation, leaf pigment content, and LMA (leaf mass area) presented differences that were consistent throughout the year, although autumn was the season with greater contrast between sun and shade plants. Our data suggest that in Mediterranean scrub shade plants the lutein pool could have an important role in the photoprotection of the photosynthetic tissues. There was a negative linear correlation between the ratio lutein/total chlorophylls and the majority of leaf level variables. The combined effect of abiotic stress factors (light and drought or light and cold) was variable-specific, in some cases enhancing differences between sun and shade plants, while in others leading to unified strategies in all scrub species. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Borgarelli, M; Savarino, P; Crosara, S; Santilli, R A; Chiavegato, D; Poggi, M; Bellino, C; La Rosa, G; Zanatta, R; Haggstrom, J; Tarducci, A
2008-01-01
There are few studies evaluating the natural history and prognostic variables in chronic mitral valve disease (CMVI) in a heterogeneous population of dogs. To estimate survival and prognostic value of clinical and echocardiographic variables in dogs with CMVI of varying severity. Five hundred and fifty-eight dogs belonging to 36 breeds were studied. Dogs were included after clinical examination and echocardiography. Long-term outcome was assessed by telephone interview with the owner. The mean follow-up time was 22.7 +/- 13.6 months, and the median survival time was 19.5 +/- 13.2 months. In univariate analysis, age>8 years, syncope, HR>140 bpm, dyspnea, arrhythmias, class of heart failure (International Small Animal Cardiac Health Council), furosemide therapy, end-systolic volume-index (ESV-I)>30 mL/m(2), left atrial to aortic root ratio (LA/Ao)>1.7, E wave transmitral peak velocity (Emax)>1.2 m/s, and bilateral mitral valve leaflet engagement were associated with survival time when all causes of death were included. For the cardiac-related deaths, all the previous variables except dyspnea and EDV-I>100 mL/m(2) were significantly associated with survival time. Significant variables in multivariate analysis (all causes of death) were syncope, LA/Ao>1.7 m/s, and Emax>1.2 m/s. For cardiac-related death, the only significant variable was LA/Ao>1.7. Mild CMVI is a relatively benign condition in dogs. However, some clinical variables can identify dogs at a higher risk of death; these variables might be useful to identify individuals that need more frequent monitoring or therapeutic intervention.
Folguera, Guillermo; Bastías, Daniel A; Caers, Jelle; Rojas, José M; Piulachs, Maria-Dolors; Bellés, Xavier; Bozinovic, Francisco
2011-07-01
Global climate change is one of the greatest threats to biodiversity; one of the most important effects is the increase in the mean earth surface temperature. However, another but poorly studied main characteristic of global change appears to be an increase in temperature variability. Most of the current analyses of global change have focused on mean values, paying less attention to the role of the fluctuations of environmental variables. We experimentally tested the effects of environmental temperature variability on characteristics associated to the fitness (body mass balance, growth rate, and survival), metabolic rate (VCO(2)) and molecular traits (heat shock protein expression, Hsp70), in an ectotherm, the terrestrial woodlouse Porcellio laevis. Our general hypotheses are that higher values of thermal amplitude may directly affect life-history traits, increasing metabolic cost and stress responses. At first, results supported our hypotheses showing a diversity of responses among characters to the experimental thermal treatments. We emphasize that knowledge about the cellular and physiological mechanisms by which animals cope with environmental changes is essential to understand the impact of mean climatic change and variability. Also, we consider that the studies that only incorporate only mean temperatures to predict the life-history, ecological and evolutionary impact of global temperature changes present important problems to predict the diversity of responses of the organism. This is because the analysis ignores the complexity and details of the molecular and physiological processes by which animals cope with environmental variability, as well as the life-history and demographic consequences of such variability. Copyright © 2011 Elsevier Inc. All rights reserved.
Scheidegger, Stephan; Fuchs, Hans U; Zaugg, Kathrin; Bodis, Stephan; Füchslin, Rudolf M
2013-01-01
In order to overcome the limitations of the linear-quadratic model and include synergistic effects of heat and radiation, a novel radiobiological model is proposed. The model is based on a chain of cell populations which are characterized by the number of radiation induced damages (hits). Cells can shift downward along the chain by collecting hits and upward by a repair process. The repair process is governed by a repair probability which depends upon state variables used for a simplistic description of the impact of heat and radiation upon repair proteins. Based on the parameters used, populations up to 4-5 hits are relevant for the calculation of the survival. The model describes intuitively the mathematical behaviour of apoptotic and nonapoptotic cell death. Linear-quadratic-linear behaviour of the logarithmic cell survival, fractionation, and (with one exception) the dose rate dependencies are described correctly. The model covers the time gap dependence of the synergistic cell killing due to combined application of heat and radiation, but further validation of the proposed approach based on experimental data is needed. However, the model offers a work bench for testing different biological concepts of damage induction, repair, and statistical approaches for calculating the variables of state.
Application of neural networks and sensitivity analysis to improved prediction of trauma survival.
Hunter, A; Kennedy, L; Henry, J; Ferguson, I
2000-05-01
The performance of trauma departments is widely audited by applying predictive models that assess probability of survival, and examining the rate of unexpected survivals and deaths. Although the TRISS methodology, a logistic regression modelling technique, is still the de facto standard, it is known that neural network models perform better. A key issue when applying neural network models is the selection of input variables. This paper proposes a novel form of sensitivity analysis, which is simpler to apply than existing techniques, and can be used for both numeric and nominal input variables. The technique is applied to the audit survival problem, and used to analyse the TRISS variables. The conclusions discuss the implications for the design of further improved scoring schemes and predictive models.
Vercelli, Marina; Lillini, Roberto; Capocaccia, Riccardo; Quaglia, Alberto
2012-12-01
The main aim of this work is to compute expected cancer survival for Italian provinces by Socio-Economic and health Resources and Technologic Supplies (SERTS) models, based on demographic, socioeconomic variables and information describing the health care system (SEH). Five-year age-standardised relative survival rates by gender for 11 cancer sites and all cancers combined of patients diagnosed in 1995-1999, were obtained from the Italian Association of Cancer Registries (CRs) database. The SEH variables describe at provincial level macro-economy, demography, labour market, health resources in 1995-2005. A principal components factor analysis was applied to the SEH variables to control their strong mutual correlation. For every considered cancer site, linear regression models were estimated considering the 5-RS% as dependent variable and the principal components factors of the SEH variables as independent variables. The model composition was correlated to the characteristics of take in charge of patients. SEH factors were correlated with the observed survival for all cancer combined and colon-rectum in both sexes, prostate, kidney and non Hodgkin's lymphomas in men, breast, corpus uteri and melanoma in women (R(2) from 40% to 85%). In the provinces without any CR the survival was very similar with that of neighbouring provinces with analogous social, economic and health characteristics. The SERTS models allowed us to interpret the survival outcome of oncologic patients with respect to the role of the socio-economic and health related system characteristics, stressing how the peculiarities of the take in charge at the province level could address the decisions regarding the allocation of resources. Copyright © 2012 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Hasyim, M.; Prastyo, D. D.
2018-03-01
Survival analysis performs relationship between independent variables and survival time as dependent variable. In fact, not all survival data can be recorded completely by any reasons. In such situation, the data is called censored data. Moreover, several model for survival analysis requires assumptions. One of the approaches in survival analysis is nonparametric that gives more relax assumption. In this research, the nonparametric approach that is employed is Multivariate Regression Adaptive Spline (MARS). This study is aimed to measure the performance of private university’s lecturer. The survival time in this study is duration needed by lecturer to obtain their professional certificate. The results show that research activities is a significant factor along with developing courses material, good publication in international or national journal, and activities in research collaboration.
Alonso-Álvarez, Sara; Magnano, Laura; Alcoceba, Miguel; Andrade-Campos, Marcio; Espinosa-Lara, Natalia; Rodríguez, Guillermo; Mercadal, Santiago; Carro, Itziar; Sancho, Juan M; Moreno, Miriam; Salar, Antonio; García-Pallarols, Francesc; Arranz, Reyes; Cannata, Jimena; Terol, María José; Teruel, Ana I; Rodríguez, Antonia; Jiménez-Ubieto, Ana; González de Villambrosia, Sonia; Bello, José L; López, Lourdes; Monsalvo, Silvia; Novelli, Silvana; de Cabo, Erik; Infante, María S; Pardal, Emilia; García-Álvarez, María; Delgado, Julio; González, Marcos; Martín, Alejandro; López-Guillermo, Armando; Caballero, María D
2017-09-01
The diagnostic criteria for follicular lymphoma (FL) transformation vary among the largest series, which commonly exclude histologically-documented transformation (HT) mandatorily. The aims of this retrospective observational multicentre study by the Spanish Grupo Español de Linfoma y Transplante Autólogo de Médula Ósea, which recruited 1734 patients (800 males/934 females; median age 59 years), diagnosed with FL grades 1-3A, were, (i) the cumulative incidence of HT (CI-HT); (ii) risk factors associated with HT; and (iii) the role of treatment and response on survival following transformation (SFT). With a median follow-up of 6·2 years, 106 patients developed HT. Ten-year CI-HT was 8%. Considering these 106 patients who developed HT, median time to transformation was 2·5 years. High-risk FL International Prognostic Index [Hazard ratio (HR) 2·6, 95% confidence interval (CI): 1·5-4·5] and non-response to first-line therapy (HR 2·9, 95% CI: 1·3-6·8) were associated with HT. Seventy out of the 106 patients died (5-year SFT, 26%). Response to HT first-line therapy (HR 5·3, 95% CI: 2·4-12·0), autologous stem cell transplantation (HR 3·9, 95% CI: 1·5-10·1), and revised International Prognostic Index (HR 2·2, 95% CI: 1·1-4·2) were significantly associated with SFT. Response to treatment and HT were the variables most significantly associated with survival in the rituximab era. Better therapies are needed to improve response. Inclusion of HT in clinical trials with new agents is mandatory. © 2017 John Wiley & Sons Ltd.
Liu, Hui; Zhang, Tiantuo; Ye, Jin; Li, Hongtao; Huang, Jing; Li, Xiaodong; Wu, Benquan; Huang, Xubing; Hou, Jinghui
2012-10-01
Accumulating preclinical evidence suggests that anticancer immune responses contribute to the success of chemotherapy. The predictive significance of tumor-infiltrating lymphocytes (TILs) for response to neoadjuvant chemotherapy in non-small cell lung cancer (NSCLC) remains unknown. The aim of this study was to investigate the prognostic and predictive value of TIL subtypes in patients with advanced NSCLC treated with platinum-based chemotherapy. In total, 159 patients with stage III and IV NSCLC were retrospectively enrolled. The prevalence of CD3(+), CD4(+), CD8(+) and Foxp3(+) TILs was assessed by immunohistochemistry in tumor tissue obtained before chemotherapy. The density of TILs subgroups was treated as dichotomous variables using the median values as cutoff. Survival curves were estimated by the Kaplan-Meier method, and differences in overall survival between groups were determined using the Log-rank test. Prognostic effects of TIL subsets density were evaluated by Cox regression analysis. The presence of CD3(+), CD4(+), CD8(+), and FOXP3(+) TILs was not correlated with any clinicopathological features. Neither the prevalence of TILs nor combined analysis displayed obvious prognostic performances for overall survival in Cox regression model. Instead, higher FOXP3(+)/CD8(+) ratio in tumor sites was an independent factor for poor response to platinum-based chemotherapy in overall cohort. These findings suggest that immunological CD8(+) and FOXP3(+)Tregs cell infiltrate within tumor environment is predictive of response to platinum-based neoadjuvant chemotherapy in advanced NSCLC patients. The understanding of the clinical relevance of the microenvironmental immunological milieu might provide an important clue for the design of novel strategies in cancer immunotherapy.
Ross, Cliff; Olsen, Kevin; Henry, Michael; Pierce, Richard
2015-04-01
The declining health of coral reefs is intensifying worldwide at an alarming rate due to the combined effects of land-based sources of pollution and climate change. Despite the persistent use of mosquito control pesticides in populated coastal areas, studies examining the survival and physiological impacts of early life-history stages of non-targeted marine organisms are limited. In order to better understand the combined effects of mosquito pesticides and rising sea surface temperatures, we exposed larvae from the coral Porites astreoides to selected concentrations of two major mosquito pesticide ingredients, naled and permethrin, and seawater elevated +3.5 °C. Following 18-20 h of exposure, larvae exposed to naled concentrations of 2.96 µg L(-1) or greater had significantly reduced survivorship compared to controls. These effects were not detected in the presence of permethrin or elevated temperature. Furthermore, larval settlement, post-settlement survival and zooxanthellae density were not impacted by any treatment. To evaluate the sub-lethal stress response of larvae, several oxidative stress endpoints were utilized. Biomarker responses to pesticide exposure were variable and contingent upon pesticide type as well as the specific biomarker being employed. In some cases, such as with protein carbonylation and catalase gene expression, the effects of naled exposure and temperature were interactive. In other cases pesticide exposure failed to induce any sub-lethal stress response. Overall, these results demonstrate that P. astreoides larvae have a moderate degree of resistance against short-term exposure to ecologically relevant concentrations of pesticides even in the presence of elevated temperature. In addition, this work highlights the importance of considering the complexity and differential responses encountered when examining the impacts of combined stressors that occur on varying spatial scales.
Huang, Steven Y; Odisio, Bruno C; Sabir, Sharjeel H; Ensor, Joe E; Niekamp, Andrew S; Huynh, Tam T; Kroll, Michael; Gupta, Sanjay
2017-07-01
Our purpose was to develop a predictive model for short-term survival (i.e. <6 months) following inferior vena cava filter placement in patients with venous thromboembolism (VTE) and solid malignancy. Clinical and laboratory parameters were retrospectively reviewed for patients with solid malignancy who received a filter between January 2009 and December 2011 at a tertiary care cancer center. Multivariate Cox proportional hazards modeling was used to assess variables associated with 6 month survival following filter placement in patients with VTE and solid malignancy. Significant variables were used to generate a predictive model. 397 patients with solid malignancy received a filter during the study period. Three variables were associated with 6 month survival: (1) serum albumin [hazard ratio (HR) 0.496, P < 0.0001], (2) recent or planned surgery (<30 days) (HR 0.409, P < 0.0001), (3) TNM staging (stage 1 or 2 vs. stage 4, HR 0.177, P = 0.0001; stage 3 vs. stage 4, HR 0.367, P = 0.0002). These variables were used to develop a predictive model to estimate 6 month survival with an area under the receiver operating characteristic curve of 0.815, sensitivity of 0.782, and specificity of 0.715. Six month survival in patients with VTE and solid malignancy requiring filter placement can be predicted from three patient variables. Our predictive model could be used to help physicians decide whether a permanent or retrievable filter may be more appropriate as well as to assess the risks and benefits for filter retrieval within the context of survival longevity in patients with cancer.
Diet and gut morphology of male mallards during winter in North Dakota
Olsen, R.E.; Cox, R.R.; Afton, A.D.; Ankney, C.D.
2011-01-01
A free-ranging Mallard (Anas platyrhynchos) population was investigated during winter (December-January 1996-1999) below the Garrison Dam, North Dakota, USA, to relate diet to gut morphology variation in males. Four explanatory variables (fish consumption, male age, winter, and body size) were evaluated as to whether they influenced five response variables associated with gut characteristics of Mallards. Response variables were lower gastro-intestinal tract mass (LGIT), dry liver mass, dry gizzard mass, small intestine length, and ceca length. Diets of Mallards were comprised primarily of Rainbow Smelt (Osmerus mordax) and concomitantly variation in gizzard mass was small. LGIT mass of juveniles was larger than that of adults, greater for those that consumed fish, and greater during the coldest and snowiest winter. Liver mass and small intestine length of Mallards that consumed fish were greater than those that did not. Mallards may maintain lengthy intestines to increase digestive efficiency. Gut size variation was not entirely attributable to dietary composition but also influenced by body size and environmental conditions such that over-winter survival is maximized.
Individual-scale inference to anticipate climate-change vulnerability of biodiversity.
Clark, James S; Bell, David M; Kwit, Matthew; Stine, Anne; Vierra, Ben; Zhu, Kai
2012-01-19
Anticipating how biodiversity will respond to climate change is challenged by the fact that climate variables affect individuals in competition with others, but interest lies at the scale of species and landscapes. By omitting the individual scale, models cannot accommodate the processes that determine future biodiversity. We demonstrate how individual-scale inference can be applied to the problem of anticipating vulnerability of species to climate. The approach places climate vulnerability in the context of competition for light and soil moisture. Sensitivities to climate and competition interactions aggregated from the individual tree scale provide estimates of which species are vulnerable to which variables in different habitats. Vulnerability is explored in terms of specific demographic responses (growth, fecundity and survival) and in terms of the synthetic response (the combination of demographic rates), termed climate tracking. These indices quantify risks for individuals in the context of their competitive environments. However, by aggregating in specific ways (over individuals, years, and other input variables), we provide ways to summarize and rank species in terms of their risks from climate change.
Pereira, Deolinda; Assis, Joana; Gomes, Mónica; Nogueira, Augusto; Medeiros, Rui
2016-05-01
The success of chemotherapy in ovarian cancer (OC) is directly associated with the broad variability in platinum response, with implications in patients survival. This heterogeneous response might result from inter-individual variations in the platinum-detoxification pathway due to the expression of glutathione-S-transferase (GST) enzymes. We hypothesized that GSTM1 and GSTT1 polymorphisms might have an impact as prognostic and predictive determinants for OC. We conducted a hospital-based study in a cohort of OC patients submitted to platinum-based chemotherapy. GSTM1 and GSTT1 genotypes were determined by multiplex PCR. GSTM1-null genotype patients presented a significantly longer 5-year survival and an improved time to progression when compared with GSTM1-wt genotype patients (log-rank test, P = 0.001 and P = 0.013, respectively). Multivariate Cox regression analysis indicates that the inclusion of genetic information regarding GSTM1 polymorphism increased the predictive ability of risk of death after OC platinum-based chemotherapy (c-index from 0.712 to 0.833). Namely, residual disease (HR, 4.90; P = 0.016) and GSTM1-wt genotype emerged as more important predictors of risk of death (HR, 2.29; P = 0.039; P = 0.036 after bootstrap). No similar effect on survival was observed regarding GSTT1 polymorphism, and there were no statistically significant differences between GSTM1 and GSTT1 genotypes and the assessed patients' clinical-pathological characteristics. GSTM1 polymorphism seems to have an impact in OC prognosis as it predicts a better response to platinum-based chemotherapy and hence an improved survival. The characterization of the GSTM1 genetic profile might be a useful molecular tool and a putative genetic marker for OC clinical outcome.
Jatem Escalante, Elías; Segarra Medrano, Alfons; Carnicer Cáceres, Clara; Martín-Gómez, M Adoración; Salcedo Allende, María Teresa; Ostos Roldan, Helena; Agraz Pamplona, Irene
2015-01-01
In membranous nephropathy, the presence of antibodies against M-type phospholipase A2 receptor is considered highly specific for idiopathic forms. However, no specific association to a particular clinical profile has been found for such antibodies. To assess potential differences in initial clinical profile, course and prognosis of idiopathic membranous nephropathy depending on the presence of anti-PLA2R antibodies. Eighty-five patients with idiopathic membranous nephropathy were included (55 anti-PLA2R-positive and 30 anti-PLA2R-negative). Clinical, biochemical and pathological variables were recorded at the time of diagnosis. Frequency of spontaneous remission, incidence of response to first-line therapy, frequency and number of recurrences, survival of renal function free from renal replacement therapy, survival of renal function free from chronic renal insufficiency and frequency of occurrence of malignant, infectious or autoimmune diseases during follow-up were recorded. At the time of diagnosis, anti-PLA2R-negative patients were significantly older and had a higher frequency of spontaneous remission. No differences were noted in the response to first-line treatment, frequency and number of recurrences, survival of renal function free from renal replacement therapy, or survival of renal function free from chronic renal insufficiency. Anti-PLA2R-negative patients with idiopathic membranous nephropathy were older and experienced spontaneous remission more often than anti-PLA2R-positive patients. No differences in terms of treatment response, recurrences, and final prognosis were observed between both groups of patients. Copyright © 2015 The Authors. Published by Elsevier España, S.L.U. All rights reserved.
NASA Astrophysics Data System (ADS)
Kim, Jung Jin; Stockhausen, William; Kim, Suam; Cho, Yang-Ki; Seo, Gwang-Ho; Lee, Joon-Soo
2015-11-01
To understand interannual variability in the distribution of the early life stages of Todarodes pacificus summer spawning population, and to identify the key transport processes influencing this variability, we used a coupled bio-physical model that combines an individual-based model (IBM) incorporating ontogenetic vertical migration for paralarval behavior and temperature-dependent survival process with a ROMS oceanographic model. Using the distribution of paralarvae observed in the northern East China Sea (ECS) during several field cruises as an end point, the spawning ground for the summer-spawning population was estimated to extend from southeast Jeju Island to the central ECS near 29°N by running the model backwards in time. Running the model forward, interannual variability in the distribution of paralarvae predicted by the model was consistent with that observed in several field surveys; surviving individuals in the northern ECS were substantially more abundant in late July 2006 than in 2007, in agreement with observed paralarval distributions. The total number of surviving individuals at 60 days after release based on the simulation throughout summer spawning period (June-August) was 20,329 for 2006, compared with 13,816 for 2007. The surviving individuals were mainly distributed in the East/Japan Sea (EJS), corresponding to a pathway following the nearshore branch of the Tsushima Warm Current flowing along the Japanese coast during both years. In contrast, the abundance of surviving individuals was extremely low in 2007 compared to 2006 on the Pacific side of Japan. Interannual variability in transport and survival processes made a substantial impact on not only the abundance of surviving paralarvae, but also on the flux of paralarvae to adjacent waters. Our simulation results for between-year variation in paralarval abundance coincide with recruitment (year n + 1) variability of T. pacificus in the field. The agreement between the simulation and field data indicates our model may be useful for predicting the recruitment of T. pacificus.
Sanjay, Pandanaboyana; de Figueiredo, Rodrigo S; Leaver, Heather; Ogston, Simon; Kulli, Christoph; Polignano, Francesco M; Tait, Iain S
2012-03-10
There is paucity of data on the prognostic value of pre-operative inflammatory response and post-operative lymph node ratio on patient survival after pancreatic-head resection for pancreatic ductal adenocarcinoma. To evaluate the role of the preoperative inflammatory response and postoperative pathology criteria to identify predictive and/or prognostic variables for pancreatic ductal adenocarcinoma. All patients who underwent pancreaticoduodenectomy for pancreatic ductal adenocarcinoma between 2002 and 2008 were reviewed retrospectively. The following impacts on patient survival were assessed: i) preoperative serum CRP levels, white cell count, neutrophil count, neutrophil/lymphocyte ratio, lymphocyte count, platelet/lymphocyte ratio; and ii) post-operative pathology criteria including lymph node status and lymph node ratio. Fifty-one patients underwent potentially curative resection for pancreatic ductal adenocarcinoma during the study period. An elevated preoperative CRP level (greater than 3 mg/L) was found to be a significant adverse prognostic factor (P=0.015) predicting a poor survival, whereas white cell count (P=0.278), neutrophil count (P=0.850), neutrophil/lymphocyte ratio (P=0.272), platelet/lymphocyte ratio (P=0.532) and lymphocyte count (P=0.721) were not significant prognosticators at univariate analysis. Presence of metastatic lymph nodes did not adversely affect survival (P=0.050), however a raised lymph node ratio predicted poor survival at univariate analysis (P<0.001). The preoperative serum CRP level retained significance at multivariate analysis (P=0.011), together with lymph node ratio (P<0.001) and tumour size (greater than 2 cm; P=0.008). A pre-operative elevated serum CRP level and raised post-operative lymph node ratio represent significant independent prognostic factors that predict poor prognosis in patients undergoing curative resection for pancreatic ductal adenocarcinoma. There is potential for future neo-adjuvant and adjuvant treatment strategies in pancreatic cancer to be tailored based on preoperative and postoperative factors that predict a poor survival.
Samad, Manar D; Ulloa, Alvaro; Wehner, Gregory J; Jing, Linyuan; Hartzel, Dustin; Good, Christopher W; Williams, Brent A; Haggerty, Christopher M; Fornwalt, Brandon K
2018-06-09
The goal of this study was to use machine learning to more accurately predict survival after echocardiography. Predicting patient outcomes (e.g., survival) following echocardiography is primarily based on ejection fraction (EF) and comorbidities. However, there may be significant predictive information within additional echocardiography-derived measurements combined with clinical electronic health record data. Mortality was studied in 171,510 unselected patients who underwent 331,317 echocardiograms in a large regional health system. We investigated the predictive performance of nonlinear machine learning models compared with that of linear logistic regression models using 3 different inputs: 1) clinical variables, including 90 cardiovascular-relevant International Classification of Diseases, Tenth Revision, codes, and age, sex, height, weight, heart rate, blood pressures, low-density lipoprotein, high-density lipoprotein, and smoking; 2) clinical variables plus physician-reported EF; and 3) clinical variables and EF, plus 57 additional echocardiographic measurements. Missing data were imputed with a multivariate imputation by using a chained equations algorithm (MICE). We compared models versus each other and baseline clinical scoring systems by using a mean area under the curve (AUC) over 10 cross-validation folds and across 10 survival durations (6 to 60 months). Machine learning models achieved significantly higher prediction accuracy (all AUC >0.82) over common clinical risk scores (AUC = 0.61 to 0.79), with the nonlinear random forest models outperforming logistic regression (p < 0.01). The random forest model including all echocardiographic measurements yielded the highest prediction accuracy (p < 0.01 across all models and survival durations). Only 10 variables were needed to achieve 96% of the maximum prediction accuracy, with 6 of these variables being derived from echocardiography. Tricuspid regurgitation velocity was more predictive of survival than LVEF. In a subset of studies with complete data for the top 10 variables, multivariate imputation by chained equations yielded slightly reduced predictive accuracies (difference in AUC of 0.003) compared with the original data. Machine learning can fully utilize large combinations of disparate input variables to predict survival after echocardiography with superior accuracy. Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Fogarty, Dillon T; Elmore, R Dwayne; Fuhlendorf, Samuel D; Loss, Scott R
2017-08-01
Habitat selection by animals is influenced by and mitigates the effects of predation and environmental extremes. For birds, nest site selection is crucial to offspring production because nests are exposed to extreme weather and predation pressure. Predators that forage using olfaction often dominate nest predator communities; therefore, factors that influence olfactory detection (e.g., airflow and weather variables, including turbulence and moisture) should influence nest site selection and survival. However, few studies have assessed the importance of olfactory cover for habitat selection and survival. We assessed whether ground-nesting birds select nest sites based on visual and/or olfactory cover. Additionally, we assessed the importance of visual cover and airflow and weather variables associated with olfactory cover in influencing nest survival. In managed grasslands in Oklahoma, USA, we monitored nests of Northern Bobwhite ( Colinus virginianus ), Eastern Meadowlark ( Sturnella magna ), and Grasshopper Sparrow ( Ammodramus savannarum ) during 2015 and 2016. To assess nest site selection, we compared cover variables between nests and random points. To assess factors influencing nest survival, we used visual cover and olfactory-related measurements (i.e., airflow and weather variables) to model daily nest survival. For nest site selection, nest sites had greater overhead visual cover than random points, but no other significant differences were found. Weather variables hypothesized to influence olfactory detection, specifically precipitation and relative humidity, were the best predictors of and were positively related to daily nest survival. Selection for overhead cover likely contributed to mitigation of thermal extremes and possibly reduced detectability of nests. For daily nest survival, we hypothesize that major nest predators focused on prey other than the monitored species' nests during high moisture conditions, thus increasing nest survival on these days. Our study highlights how mechanistic approaches to studying cover informs which dimensions are perceived and selected by animals and which dimensions confer fitness-related benefits.
NASA Astrophysics Data System (ADS)
Tran, Annelise; Goutard, Flavie; Chamaillé, Lise; Baghdadi, Nicolas; Lo Seen, Danny
2010-02-01
Recent studies have highlighted the potential role of water in the transmission of avian influenza (AI) viruses and the existence of often interacting variables that determine the survival rate of these viruses in water; the two main variables are temperature and salinity. Remote sensing has been used to map and monitor water bodies for several decades. In this paper, we review satellite image analysis methods used for water detection and characterization, focusing on the main variables that influence AI virus survival in water. Optical and radar imagery are useful for detecting water bodies at different spatial and temporal scales. Methods to monitor the temperature of large water surfaces are also available. Current methods for estimating other relevant water variables such as salinity, pH, turbidity and water depth are not presently considered to be effective.
Carrera, Gemma; Garcia-Albeniz, Xabier; Ayuso, Juan Ramón; Aparicio, Jorge; Castells, Antoni; Codony-Servat, Jordi; Feliu, Jaime; Fuster, David; Gallego, Rosa; Pagés, Mario; Torres, Ferran; Maurel, Joan
2011-05-01
Meta-analytic reviews of Randomized Clinical Trials (RCT) have reached contradictory conclusions regarding the benefit of medical interventions in Advanced Colorectal Cancer (ACRC). Surrogate markers of survival benefit, such as response rate (RR) and progression free-survival (PFS) often show contradictory and highly variable correlations. These contradictions can be due to differences in 1) the studies analysed (sources), 2) the quality of clinical trials (intrinsic bias in the design, biased data analysis, heterogeneous PFS definitions) and 3) the second-line strategies between arms. PFS is a more vulnerable target than overall survival (OS), but the latter can also be affected by different biases and additional medical interventions such as secondary resection of metastases or second-line therapies. Therefore the correlation between PFS and survival must be clearly stated if PFS is to be considered as a primary endpoint. Of the differences between studies, only the quality of clinical trials can be improved by a deeper knowledge of both the area of study (i.e. colorectal cancer) and the methodology needed (i.e., clinical and translational trials). The aim of this manuscript is to offer the basic resources to develop experimental trials in ACRC. To this end, techniques for diagnosis and for response assessment are discussed, prognostic factors and treatment standards are critically exposed, and notes about how to design useful translational studies are provided.
Rossi, F; Sabattini, S; Vascellari, M; Marconato, L
2018-05-27
In dogs, inflammatory mammary carcinoma is a clinicopathological entity characterized by rapid progression and aggressive behavior from onset of disease. Reported median survival time is short, with no effective treatment options. The aims of this prospective, noncontrolled clinical trial were to investigate outcome variables and safety profile of toceranib, thalidomide and piroxicam with or without hypofractionated radiation therapy in dogs with measurable histologically confirmed inflammatory mammary carcinoma that underwent a complete staging. Eighteen dogs were enrolled: 14 received medical treatment, and 4 were treated with hypofractionated radiation therapy and medical therapy. Overall, median time to progression was 34 days and median survival time was 109 days. In dogs treated with medical therapy, overall response rate was 21%, and clinical benefit rate (CBR) was 64%; median time to progression was 28 days and median survival time was 59 days. In dogs receiving medical therapy and undergoing radiation therapy, overall response rate and clinical benefit rate were 100%, with significantly longer time to progression (156 days) and survival time (180 days). Overall, treatment was well tolerated, with mild gastrointestinal and dermatological adverse events. Although the optimal treatment to this disease remains uncertain, the current approach consisting of systemic anti-angiogenic drugs with or without hypofractionated radiation therapy, provided clinical benefit in a significant proportion of dogs and should, therefore, be further explored. © 2018 John Wiley & Sons Ltd.
Austin, Peter C
2018-01-01
Propensity score methods are frequently used to estimate the effects of interventions using observational data. The propensity score was originally developed for use with binary exposures. The generalized propensity score (GPS) is an extension of the propensity score for use with quantitative or continuous exposures (e.g. pack-years of cigarettes smoked, dose of medication, or years of education). We describe how the GPS can be used to estimate the effect of continuous exposures on survival or time-to-event outcomes. To do so we modified the concept of the dose-response function for use with time-to-event outcomes. We used Monte Carlo simulations to examine the performance of different methods of using the GPS to estimate the effect of quantitative exposures on survival or time-to-event outcomes. We examined covariate adjustment using the GPS and weighting using weights based on the inverse of the GPS. The use of methods based on the GPS was compared with the use of conventional G-computation and weighted G-computation. Conventional G-computation resulted in estimates of the dose-response function that displayed the lowest bias and the lowest variability. Amongst the two GPS-based methods, covariate adjustment using the GPS tended to have the better performance. We illustrate the application of these methods by estimating the effect of average neighbourhood income on the probability of survival following hospitalization for an acute myocardial infarction.
Hwang, Jeong-Hwa; Misumi, Shigeki; Curran-Everett, Douglas; Brown, Kevin K; Sahin, Hakan; Lynch, David A
2011-08-01
The aim of this study was to evaluate the prognostic implications of computed tomography (CT) and physiologic variables at baseline and on sequential evaluation in patients with fibrosing interstitial pneumonia. We identified 72 patients with fibrosing interstitial pneumonia (42 with idiopathic disease, 30 with collagen vascular disease). Pulmonary function tests and CT were performed at the time of diagnosis and at a median follow-up of 12 months, respectively. Two chest radiologists scored the extent of specific abnormalities and overall disease on baseline and follow-up CT. Rate of survival was estimated using the Kaplan-Meier method. Three Cox proportional hazards models were constructed to evaluate the relationship between CT and physiologic variables and rate of survival: model 1 included only baseline variables, model 2 included only serial change variables, and model 3 included both baseline and serial change variables. On follow-up CT, the extent of mixed ground-glass and reticular opacities (P<0.001), pure reticular opacity (P=0.04), honeycombing (P=0.02), and overall extent of disease (P<0.001) was increased in the idiopathic group, whereas these variables remained unchanged in the collagen vascular disease group. Patients with idiopathic disease had a shorter rate of survival than those with collagen vascular disease (P=0.03). In model 1, the extent of honeycombing on baseline CT was the only independent predictor of mortality (P=0.02). In model 2, progression in honeycombing was the only predictor of mortality (P=0.005). In model 3, baseline extent of honeycombing and progression of honeycombing were the only independent predictors of mortality (P=0.001 and 0.002, respectively). Neither baseline nor serial change physiologic variables, nor the presence of collagen vascular disease, was predictive of rate of survival. The extent of honeycombing at baseline and its progression on follow-up CT are important determinants of rate of survival in patients with fibrosing interstitial pneumonia.
Nuclear fear and children: the impact of parental nuclear activism, responsivity, and fear
DOE Office of Scientific and Technical Information (OSTI.GOV)
LaGuardia, M.R.
1986-01-01
This study examines the extent to which parental nuclear fear, parental activism, and parental responsivity is associated with children's (age 10) nuclear fear. Other associated variables investigated include: nuclear denial, general anxiety and fear, and the personal characteristics of sex, socio-economic status, and academic aptitude. Findings indicate that children attend to nuclear issues when their parents attend to a significant degree. Children's hopelessness about the arms race is increased as parents' worry about nuclear war increases. Children's fear about not surviving a nuclear war increases as parents' worry about survivability decreases. Children who have more general fears also indicated thatmore » they have a high level of hopelessness, pervasive worry, and much concern about being able to survive a nuclear war. Children with a high degree of general anxiety did not indicate high degrees of nuclear fears. Children with high academic aptitude were more knowledgeable about nuclear issues and expressed more fears about the nuclear threat. Boys demonstrated more knowledge about nuclear issues than girls, and girls expressed much more frequent fear and worry about the nuclear threat than boys. Parents of lower socio-economic statues (SES) expressed more denial about the nuclear threat and were more pro-military than the higher SES parents.« less
Niemira, Brendan A; Sommers, Christopher H; Boyd, Glenn
2003-10-01
Six strains of Salmonella (Anatum F4317, Dublin 15480, Enteritidis 13076, Enteritidis WY15159, Stanley H0588, and Typhimurium 14028) were individually inoculated into orange juice concentrate (OJC) and frozen to -20 degrees C. The frozen samples were treated with 0 (nonirradiated), 0.5, 1.0, or 2.0 kGy of gamma radiation and held frozen for 1 h, and the surviving bacterial population was assessed. The strains showed significant variability in their response to freezing and to freezing in combination with irradiation. The response was dose dependent. Relative to the nonfrozen, nonirradiated control, the reduction following the highest dose (2.0 kGy) ranged from 1.29 log CFU/ml (Salmonella Typhimurium) to 2.17 log CFU/ml (Salmonella Stanley). Samples of OJC inoculated with Salmonella Enteritidis WY15159 and irradiated were stored at -20 degrees C for 1, 2, 7, or 14 days, and the surviving population was determined. Relative to the nonfrozen, nonirradiated control, after 14 days, the population was reduced by 1.2 log CFU/ml in the nonirradiated samples and by 3.3 log CFU/ml following treatment with 2.0 kGy. The combination of frozen storage plus irradiation resulted in greater overall reductions than either process alone.
Massie, Michelle R.; Lapoczka, Elizabeth M.; Boggs, Kristy D.; Stine, Karen E.; White, Glenn E.
2003-01-01
Historically, sodium azide has been used to anesthetize the nematode Caenorhabditis elegans; however, the mechanism by which it survives this exposure is not understood. In this study, we report that exposure of wild-type C elegans to 10 mM sodium azide for up to 90 minutes confers thermotolerance (defined as significantly increased survival probability [SP] at 37°C) on the animal. In addition, sodium dodecyl sulfate–polyacrylamide gel electrophoresis revealed enhanced Hsp70 expression, whereas Western blot analysis revealed the induction of Hsp16. We also tested the only known C elegans Hsp mutant daf-21 (codes for Hsp90), which constitutively enters the stress-resistant state known as the dauer larvae. Daf-21 mutants also acquire sodium azide–induced thermotolerance, whereas 3 non-Hsp, constitutive dauer-forming mutants exhibited a variable response to azide exposure. We conclude that the ability of C elegans to survive exposure to azide is associated with the induction of at least 2 stress proteins. PMID:12820649
Surrogate Endpoints and Risk Adaptive Strategies in Previously Untreated Follicular Lymphoma.
Narkhede, Mayur S; Cheson, Bruce D
2018-05-05
Follicular lymphoma is the second most common subtype of non-Hodgkin lymphoma with an estimated 3.18 cases per 100,000 people. Despite the prolongation of survival with chemoimmunotherapy, variability in response to initial treatment and outcome still exists. Whereas prolonging overall survival is important, it is generally an unreasonable primary endpoint in the front-line setting. The long follow-up needed and the influence of subsequent therapies creates a potential bias. Thus, clinical trials require approximately 5 to 8 years from activation to completion and analysis of outcomes. This duration results in enormous cost and a delay in developing newer therapies. Thus, there is a need to identify markers or surrogate endpoints that can be used in clinical trials to expedite the development of new treatments. This review will discuss various clinical, radiologic, and laboratory measures used to assess outcomes and overall survival in patients with untreated follicular lymphoma, and gauge their utility in clinical trials as surrogate endpoints. Copyright © 2018 Elsevier Inc. All rights reserved.
Wilson, Reda J; O'Neil, M E; Ntekop, E; Zhang, Kevin; Ren, Y
2014-01-01
Calculating accurate estimates of cancer survival is important for various analyses of cancer patient care and prognosis. Current US survival rates are estimated based on data from the National Cancer Institute's (NCI's) Surveillance, Epidemiology, and End RESULTS (SEER) program, covering approximately 28 percent of the US population. The National Program of Cancer Registries (NPCR) covers about 96 percent of the US population. Using a population-based database with greater US population coverage to calculate survival rates at the national, state, and regional levels can further enhance the effective monitoring of cancer patient care and prognosis in the United States. The first step is to establish the coding completeness and coding quality of the NPCR data needed for calculating survival rates and conducting related validation analyses. Using data from the NPCR-Cancer Surveillance System (CSS) from 1995 through 2008, we assessed coding completeness and quality on 26 data elements that are needed to calculate cancer relative survival estimates and conduct related analyses. Data elements evaluated consisted of demographic, follow-up, prognostic, and cancer identification variables. Analyses were performed showing trends of these variables by diagnostic year, state of residence at diagnosis, and cancer site. Mean overall percent coding completeness by each NPCR central cancer registry averaged across all data elements and diagnosis years ranged from 92.3 percent to 100 percent. RESULTS showing the mean percent coding completeness for the relative survival-related variables in NPCR data are presented. All data elements but 1 have a mean coding completeness greater than 90 percent as was the mean completeness by data item group type. Statistically significant differences in coding completeness were found in the ICD revision number, cause of death, vital status, and date of last contact variables when comparing diagnosis years. The majority of data items had a coding quality greater than 90 percent, with exceptions found in cause of death, follow-up source, and the SEER Summary Stage 1977, and SEER Summary Stage 2000. Percent coding completeness and quality are very high for variables in the NPCR-CSS that are covariates to calculating relative survival. NPCR provides the opportunity to calculate relative survival that may be more generalizable to the US population.
Wijgerde, Tim; Dini-Andreote, Francisco; Eriksson, Britas Klemens; Salles, Joana Falcão; Pen, Ido; Wild, Christian
2017-01-01
Recent research suggests that prior exposure of several months to elevated irradiance induces enhanced thermal tolerance in scleractinian corals. While this tolerance has been reported at the species level, individual coral colonies may react differently due to individual variability in thermal tolerance. As thermal anomalies are predicted to become common in the upcoming future, intraspecific variation may be key to the survival of coral populations. In order to study light-history based thermal stress responses on individual colonies, we developed a preliminary microcosm experiment where three randomly chosen, aquacultured colonies of the model coral Stylophora pistillata were exposed to two irradiance treatments (200 and 400 μmol photons m−2 s−1) for 31 days, followed by artificially induced heat stress (∼33.4 °C). We found different responses to occur at both the intraspecific and the intracolonial levels, as indicated by either equal, less severe, delayed, and/or even non-necrotic responses of corals previously exposed to the irradiance of 400 compared to 200 μmol photons m−2 s−1. In addition, all individual colonies revealed light-enhanced calcification. Finally, elevated irradiance resulted in a lower chlorophyll a concentration in one colony compared to the control treatment, and the same colony displayed more rapid bleaching compared to the other ones. Taken together, this study highlights the potential importance of intra-individual variability in physiological responses of scleractinian corals and provides recommendations for improving methodological designs for future studies. PMID:29038747
What are the physiological and immunological responses of coral to climate warming and disease?
Mydlarz, Laura D; McGinty, Elizabeth S; Harvell, C Drew
2010-03-15
Coral mortality due to climate-associated stress is likely to increase as the oceans get warmer and more acidic. Coral bleaching and an increase in infectious disease are linked to above average sea surface temperatures. Despite the uncertain future for corals, recent studies have revealed physiological mechanisms that improve coral resilience to the effects of climate change. Some taxa of bleached corals can increase heterotrophic food intake and exchange symbionts for more thermally tolerant clades; this plasticity can increase the probability of surviving lethal thermal stress. Corals can fight invading pathogens with a suite of innate immune responses that slow and even arrest pathogen growth and reduce further tissue damage. Several of these responses, such as the melanin cascade, circulating amoebocytes and antioxidants, are induced in coral hosts during pathogen invasion or disease. Some components of immunity show thermal resilience and are enhanced during temperature stress and even in bleached corals. These examples suggest some plasticity and resilience to cope with environmental change and even the potential for evolution of resistance to disease. However, there is huge variability in responses among coral species, and the rate of climate change is projected to be so rapid that only extremely hardy taxa are likely to survive the projected changes in climate stressors.
Vishnubalaji, Radhakrishnan; Manikandan, Muthurangan; Fahad, Mohamed; Hamam, Rimi; Alfayez, Musaad; Kassem, Moustapha; Aldahmash, Abdullah; Alajez, Nehad M.
2018-01-01
Tumour heterogeneity leads to variable clinical response and inaccurate diagnostic and prognostic assessment. Cancer stem cells (CSCs) represent a subpopulation responsible for invasion, metastasis, therapeutic resistance, and recurrence in many human cancer types. However, the true identity of colorectal cancer (CRC) SCs remains elusive. Here, we aimed to characterize and define the gene expression portrait of CSCs in CRC-model SW403 cells. We found that ALDH+ positive cells are clonogenic and highly proliferative; their global gene expression profiling-based molecular signature revealed gene enrichment related to DNA damage, MAPK, FAK, oxidative stress response, and Wnt signalling. ALDH+ cells showed enhanced ROS stress resistance, whereas MAPK/FAK pathway pharmacologic inhibition limited their survival. Conversely, 5-fluorouracil increased the ALDH+ cell fraction among the SW403, HCT116 and SW620 CRC models. Notably, analysis of ALDH1A1 and POU5F1 expression levels in cohorts of 462 or 420 patients for overall (OS) or disease-free (DFS) survival, respectively, obtained from the Cancer Genome Atlas CRC dataset, revealed strong association between elevated expression and poor OS (p = 0.006) and poor DFS (p = 0.05), thus implicating ALDH1A1 and POU5F1 in CRC prognosis. Our data reveal distinct molecular signature of ALDH+ CSCs in CRC and suggest pathways relevant for successful targeted therapies and management of CRC. PMID:29568377
Feinerman, Ofer; Jentsch, Garrit; Tkach, Karen E; Coward, Jesse W; Hathorn, Matthew M; Sneddon, Michael W; Emonet, Thierry; Smith, Kendall A; Altan-Bonnet, Grégoire
2010-01-01
Understanding how the immune system decides between tolerance and activation by antigens requires addressing cytokine regulation as a highly dynamic process. We quantified the dynamics of interleukin-2 (IL-2) signaling in a population of T cells during an immune response by combining in silico modeling and single-cell measurements in vitro. We demonstrate that IL-2 receptor expression levels vary widely among T cells creating a large variability in the ability of the individual cells to consume, produce and participate in IL-2 signaling within the population. Our model reveals that at the population level, these heterogeneous cells are engaged in a tug-of-war for IL-2 between regulatory (Treg) and effector (Teff) T cells, whereby access to IL-2 can either increase the survival of Teff cells or the suppressive capacity of Treg cells. This tug-of-war is the mechanism enforcing, at the systems level, a core function of Treg cells, namely the specific suppression of survival signals for weakly activated Teff cells but not for strongly activated cells. Our integrated model yields quantitative, experimentally validated predictions for the manipulation of Treg suppression. PMID:21119631
Radiation Gene-expression Signatures in Primary Breast Cancer Cells.
Minafra, Luigi; Bravatà, Valentina; Cammarata, Francesco P; Russo, Giorgio; Gilardi, Maria C; Forte, Giusi I
2018-05-01
In breast cancer (BC) care, radiation therapy (RT) is an efficient treatment to control localized tumor. Radiobiological research is needed to understand molecular differences that affect radiosensitivity of different tumor subtypes and the response variability. The aim of this study was to analyze gene expression profiling (GEP) in primary BC cells following irradiation with doses of 9 Gy and 23 Gy delivered by intraoperative electron radiation therapy (IOERT) in order to define gene signatures of response to high doses of ionizing radiation. We performed GEP by cDNA microarrays and evaluated cell survival after IOERT treatment in primary BC cell cultures. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to validate candidate genes. We showed, for the first time, a 4-gene and a 6-gene signature, as new molecular biomarkers, in two primary BC cell cultures after exposure at 9 Gy and 23 Gy respectively, for which we observed a significantly high survival rate. Gene signatures activated by different doses of ionizing radiation may predict response to RT and contribute to defining a personalized biological-driven treatment plan. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.
Non-operative management of rectal cancer: understanding tumor biology.
Wei, Iris H; Garcia-Aguilar, Julio
2018-05-24
The management of locally advanced rectal cancer involves a combination of chemotherapy, chemoradiation, and surgical resection to provide excellent local tumor control and overall survival. However, aspects of this multimodality approach are associated with significant morbidity and longterm sequelae. In addition, there is growing evidence that patients with a clinical complete response to chemotherapy and chemoradiation treatments may be safely offered initial non-operative management in a rigorous surveillance program. Developing effective methods, such as molecular biomarkers, to predict a patient's response to therapies are therefore needed to help guide personalized treatment strategies. The treatment of locally advanced rectal cancer focuses on a multimodality approach of systemic chemotherapy, radiation, and total mesorectal excision to maximize oncologic outcomes. While combined modality treatment for LARC results in excellent local tumor control and patient survival, the treatments are associated with significant morbidity and long-term functional complications that can impair quality of life. In addition, the tumor response to neoadjuvant therapy is quite variable.2 Weighed against the morbidity and significant sequelae of rectal resection, recognizing how to best optimize nonoperative strategies without compromising oncologic outcomes is critical to our understanding and treatment of this disease.
Haga, Yoshio; Ikejiri, Koji; Wada, Yasuo; Ikenaga, Masakazu; Koike, Shoichiro; Nakamura, Seiji; Koseki, Masato
2015-06-01
Surgical audit is an essential task for the estimation of postoperative outcome and comparison of quality of care. Previous studies on surgical audits focused on short-term outcomes, such as postoperative mortality. We propose a surgical audit evaluating long-term outcome following colorectal cancer surgery. The predictive model for this audit is designated as 'Estimation of Postoperative Overall Survival for Colorectal Cancer (EPOS-CC)'. Thirty-one tumor-related and physiological variables were prospectively collected in 889 patients undergoing elective resection for colorectal cancer between April 2005 and April 2007 in 16 Japanese hospitals. Postoperative overall survival was assessed over a 5-years period. The EPOS-CC score was established by selecting significant variables in a uni- and multivariate analysis and allocating a risk-adjusted multiplication factor to each variable using Cox regression analysis. For validation, the EPOS-CC score was compared to the predictive power of UICC stage. Inter-hospital variability of the observed-to-estimated 5-years survival was assessed to estimate quality of care. Among the 889 patients, 804 (90%) completed the 5-years follow-up. Univariate analysis displayed a significant correlation with 5-years survival for 14 physiological and nine tumor-related variables (p < 0.005). Highly significant p-values below 0.0001 were found for age, ASA score, severe pulmonary disease, respiratory history, performance status, hypoalbuminemia, alteration of hemoglobin, serum sodium level, and for all histological variables except tumor location. Age, TNM stage, lymphatic invasion, performance status, and serum sodium level were independent variables in the multivariate analysis and were entered the EPOS-CC model for the prediction of survival. Risk-adjusted multiplication factors between 1.5 (distant metastasis) and 0.16 (serum sodium level) were accorded to the different variables. The predictive power of EPOS-CC was superior to the one of UICC stage; area under the curve 0.87, 95% CI 0.85-0.90 for EPOS-CC, and 0.80, 0.76-0.83 for UICC stage, p < 0.001. Quality of care did not differ between hospitals. The EPOS-CC score including the independent variables age, performance status, serum sodium level, TNM stage, and lymphatic invasion is superior to the UICC stage in the prediction of 5-years overall survival. This higher accuracy might be explained by the inclusion of physiological factors, thus also taking non-tumor-associated deaths into account. Furthermore, EPOS-CC score may compare quality of care among different institutions. Future studies are necessary to further evaluate this score and help improving the prediction of long-term survival following colorectal cancer surgery.
Kim, Ellen; Kim, Jong S; Choi, Mehee; Thomas, Charles R
2016-04-01
Conditional survival can provide valuable information for both patients and healthcare providers about the changing prognosis in surviving patients over time. This study estimated conditional survival for patients with anal cancer in the United States through analysis of a national population-based cancer registry. Log-rank test identified significant covariates of cause-specific survival (defined as time from diagnosis until death from anal cancer). Significant covariates were considered in the multivariable regression of cause-specific survival using Cox proportional hazards models. Covariates included cancer stage and demographic variables. Patients in Surveillance, Epidemiology, and End Results regions diagnosed with anal squamous cell carcinoma as their first and only cancer diagnosis from 1988 to 2012 were selected from this database, and 5145 patients were included in the retrospective cohort study. Five-year conditional survival stratified by each variable in the final Cox models was measured : The final multivariable models of overall and cause-specific survivals included stage, grade, sex, age, race, and relationship status. Over the first 6 years after diagnosis, conditional survival of distant stage increased from 37% to 89%, whereas regional stage increased from 65% to 93% and localized stage increased from 84% to 96%. The other variables had increasing prognosis as well, but the subgroups increased at a more similar rate over time. The data source used does not include information on chemotherapy treatment, patient comorbidities, or socioeconomic status. Conditional survival showed improvement over time. Patients with advanced stage had the greatest improvement in conditional survival. This is the first study to provide specific conditional survival probabilities for patients with anal cancer.
Causal inference in survival analysis using pseudo-observations.
Andersen, Per K; Syriopoulou, Elisavet; Parner, Erik T
2017-07-30
Causal inference for non-censored response variables, such as binary or quantitative outcomes, is often based on either (1) direct standardization ('G-formula') or (2) inverse probability of treatment assignment weights ('propensity score'). To do causal inference in survival analysis, one needs to address right-censoring, and often, special techniques are required for that purpose. We will show how censoring can be dealt with 'once and for all' by means of so-called pseudo-observations when doing causal inference in survival analysis. The pseudo-observations can be used as a replacement of the outcomes without censoring when applying 'standard' causal inference methods, such as (1) or (2) earlier. We study this idea for estimating the average causal effect of a binary treatment on the survival probability, the restricted mean lifetime, and the cumulative incidence in a competing risks situation. The methods will be illustrated in a small simulation study and via a study of patients with acute myeloid leukemia who received either myeloablative or non-myeloablative conditioning before allogeneic hematopoetic cell transplantation. We will estimate the average causal effect of the conditioning regime on outcomes such as the 3-year overall survival probability and the 3-year risk of chronic graft-versus-host disease. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Schofield, Pamela J.; Peterson, Mark S.; Lowe, Michael R.; Brown-Peterson, Nancy J.; Slack, William T.
2011-01-01
The physiological tolerances of non-native fishes is an integral component of assessing potential invasive risk. Salinity and temperature are environmental variables that limit the spread of many non-native fishes. We hypothesised that combinations of temperature and salinity will interact to affect survival, growth, and reproduction of Nile tilapia, Oreochromis niloticus, introduced into Mississippi, USA. Tilapia withstood acute transfer from fresh water up to a salinity of 20 and survived gradual transfer up to 60 at typical summertime (30°C) temperatures. However, cold temperature (14°C) reduced survival of fish in saline waters ≥10 and increased the incidence of disease in freshwater controls. Although fish were able to equilibrate to saline waters in warm temperatures, reproductive parameters were reduced at salinities ≥30. These integrated responses suggest that Nile tilapia can invade coastal areas beyond their point of introduction. However, successful invasion is subject to two caveats: (1) wintertime survival depends on finding thermal refugia, and (2) reproduction is hampered in regions where salinities are ≥30. These data are vital to predicting the invasion of non-native fishes into coastal watersheds. This is particularly important given the predicted changes in coastal landscapes due to global climate change and sea-level rise.
Factors affecting viability of Bifidobacterium bifidum during spray drying.
Shokri, Zahra; Fazeli, Mohammad Reza; Ardjmand, Mehdi; Mousavi, Seyyed Mohammad; Gilani, Kambiz
2015-01-25
There is substantial clinical data supporting the role of Bifidobacterium bifidum in human health particularly in benefiting the immune system and suppressing intestinal infections. Compared to the traditional lyophilization, spray-drying is an economical process for preparing large quantities of viable microorganisms. The technique offers high production rates and low operating costs but is not usually used for drying of substances prone to high temperature. The aim of this study was to establish the optimized environmental factors in spray drying of cultured bifidobacteria to obtain a viable and stable powder. The experiments were designed to test variables such as inlet air temperature, air pressure and also maltodextrin content. The combined effect of these variables on survival rateand moisture content of bacterial powder was studied using a central composite design (CCD). Sub-lethal heat-adaptation of a B. bifidum strain which was previously adapted to acid-bile-NaCl led to much more resistance to high outlet temperature during spray drying. The resistant B. bifidum was supplemented with cost friendly permeate, sucrose, yeast extract and different amount of maltodextrin before it was fed into a Buchi B-191 mini spray-dryer. Second-order polynomials were established to identify the relationship between the responses andthe three variables. Results of verification experiments and predicted values from fitted correlations were in close agreement at 95% confidence interval. The optimal values of the variables for maximum survival and minimum moisture content of B. bifidum powder were as follows: inlet air temperature of 111.15°C, air pressure of 4.5 bar and maltodextrin concentration of 6%. Under optimum conditions, the maximum survival of 28.38% was achieved while moisture was maintained at 4.05%. Viable and cost effective spray drying of Bifidobacterium bifidum could be achieved by cultivating heat and acid adapted strain into the culture media containing nutritional protective agents.
Long-term population dynamics of a managed burrowing owl colony
Barclay, John H.; Korfanta, Nicole M.; Kauffman, Matthew J.
2011-01-01
We analyzed the population dynamics of a burrowing owl (Athene cunicularia) colony at Mineta San Jose International Airport in San Jose, California, USA from 1990-2007. This colony was managed by using artificial burrows to reduce the occurrence of nesting owls along runways and within major airport improvement projects during the study period. We estimated annual reproduction in natural and artificial burrows and age-specific survival rates with mark-recapture techniques, and we estimated the relative contribution of these vital rates to population dynamics using a life table response experiment. The breeding colony showed 2 distinct periods of change: high population growth from 7 nesting pairs in 1991 to 40 pairs in 2002 and population decline to 17 pairs in 2007. Reproduction was highly variable: annual nesting success (pairs that raised =1 young) averaged 79% and ranged from 36% to 100%, whereas fecundity averaged 3.36 juveniles/pair and ranged from 1.43 juveniles/pair to 4.54 juveniles/pair. We estimated annual adult survival at 0.710 during the period of colony increase from 1996 to 2001 and 0.465 during decline from 2002 to 2007, but there was no change in annual survival of juveniles between the 2 time periods. Long-term population growth rate (lambda) estimated from average vital rates was lambdaa=1.072 with lambdai=1.288 during colony increase and lambdad=0.921 (DELTA lambda=0.368) during decline. A life table response experiment showed that change in adult survival rate during increasing and declining phases explained more than twice the variation in growth rate than other vital rates. Our findings suggest that management and conservation of declining burrowing owl populations should address factors that influence adult survival.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yu, S; Green, G; Sehgal, V
Purpose: The purpose of this study is to assess the dose response of radioembolization using yttrium-90 (Y-90) microspheres in patients treated for unresectable cholangiocarcinoma. This study utilized partition dosimetry model for the dose calculation. The results show survival benefit with dose escalation. Methods: Between February 2009 and March 2013, ten patients with pathology proven unresectable cholangiocarcinoma were radioembolized with Y-90 microspheres. Patients underwent initial pre-treatment angiographic assessment for blood flow and 99mTc- MAA for lung shunt evaluation. Activity of Y-90 administration was calculated using the Body Surface Area (BSA) and target volumes which were determined by contouring the pre-treatment MRI/CTmore » images using a radiation therapy treatment planning system. Medical Internal Radiation Dose (MIRD) method was used to assess the dosimetric results of Y90. Partition model based on the tumor to-liver activity uptake estimated from pretreatment 99mTc- MAA study was used to calculate the dose delivered to the target. The variables assessed included: administered dose, toxicity based on clinical changes, imaging based tumor response, and survival. Results: Ten patients were radioembolized with Y-90 microspheres to either one hepatic lobe or both left and right lobes. Patients were stratified by dose. Four patients who received dose greater than 140Gy (p < 0.05) all survived. The corresponding activity they received was greater than 35 mCi. Six out of ten patients died of disease with median survival of 18 weeks (range 12–81wks). Conclusion: Given the growing body of data for Y-90 microspheres in the context of cholangiocarcinoma, radioembolization may become an important treatment modality for an appropriately selected group of patients. Our study further substantiates past studies and shows additional evidence of a survival benefit with dose escalation.« less
Griffis-Kyle, Kerry L; Ritchie, Mark E
2007-07-01
Mineral nitrogen (N) has been suggested as a potential factor causing declines in amphibian populations, especially in agricultural landscapes; however, there is a question as to whether it remains in the water column long enough to be toxic. We explored the hypothesis that mineral N can cause both lethal and sublethal toxic effects in amphibian embryos and larvae in a manipulative field experiment. We sampled 12 ponds, fertilizing half with ammonium nitrate fertilizer early in the spring, and measured hatching, survival, development, growth, and the incidence of deformities in native populations of wood frog (Rana sylvatica) and eastern tiger salamander (Ambystoma tigrinum tigrinum) embryos and larvae held in in situ enclosures. We found that higher ammonium concentrations negatively affect R. sylvatica more strongly than A. tigrinum. R. sylvatica tended to have lower survival as embryos and young tadpoles, slowed embryonic development, and an increased proportion of hatchlings with deformities at experimentally elevated ammonium. A. tigrinum did not experience significantly reduced survival, but their larval development was slowed in response to elevated ammonium and the abundance of large invertebrate predators. Variable species susceptibility, such as that shown by R sylvatica and A. tigrinum, could have large indirect effects on aquatic community structure through modification of competitive or predator-prey relationships. Ammonium and nitrate + nitrite concentrations were not correlated with other measures that might have affected amphibians, such as pH, pond area, depth, or vegetation. Our results highlight the potential importance of elevated ammonium on the growth, development and survival of amphibians, especially those that breed in surface waters receiving anthropogenic N inputs.
The UK Out of Hospital Cardiac Arrest Outcome (OHCAO) project.
Perkins, Gavin D; Brace-McDonnell, Samantha J
2015-10-01
Reducing premature death is a key priority for the UK National Health Service (NHS). NHS Ambulance services treat approximately 30 000 cases of suspected cardiac arrest each year but survival rates vary. The British Heart Foundation and Resuscitation Council (UK) have funded a structured research programme--the Out of Hospital Cardiac Arrest Outcomes (OHCAO) programme. The aim of the project is to establish the epidemiology and outcome of OHCA, explore sources of variation in outcome and establish the feasibility of setting up a national OHCA registry. This is a prospective observational study set in UK NHS Ambulance Services. The target population will be adults and children sustaining an OHCA who are attended by an NHS ambulance emergency response and where resuscitation is attempted. The data collected will be characterised broadly as system characteristics, emergency medical services (EMS) dispatch characteristics, patient characteristics and EMS process variables. The main outcome variables of interest will be return of spontaneous circulation and medium-long-term survival (30 days to 10-year survival). Ethics committee permissions were gained and the study also has received approval from the Confidentiality Advisory Group Ethics and Confidentiality committee which provides authorisation to lawfully hold identifiable data on patients without their consent. To identify the key characteristics contributing to better outcomes in some ambulance services, reliable and reproducible systems need to be established for collecting data on OHCA in the UK. Reports generated from the registry will focus on data completeness, timeliness and quality. Subsequent reports will summarise demographic, patient, process and outcome variables with aim of improving patient care through focus quality improvement initiatives. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Cardiovascular reactivity patterns and pathways to hypertension: a multivariate cluster analysis.
Brindle, R C; Ginty, A T; Jones, A; Phillips, A C; Roseboom, T J; Carroll, D; Painter, R C; de Rooij, S R
2016-12-01
Substantial evidence links exaggerated mental stress induced blood pressure reactivity to future hypertension, but the results for heart rate reactivity are less clear. For this reason multivariate cluster analysis was carried out to examine the relationship between heart rate and blood pressure reactivity patterns and hypertension in a large prospective cohort (age range 55-60 years). Four clusters emerged with statistically different systolic and diastolic blood pressure and heart rate reactivity patterns. Cluster 1 was characterised by a relatively exaggerated blood pressure and heart rate response while the blood pressure and heart rate responses of cluster 2 were relatively modest and in line with the sample mean. Cluster 3 was characterised by blunted cardiovascular stress reactivity across all variables and cluster 4, by an exaggerated blood pressure response and modest heart rate response. Membership to cluster 4 conferred an increased risk of hypertension at 5-year follow-up (hazard ratio=2.98 (95% CI: 1.50-5.90), P<0.01) that survived adjustment for a host of potential confounding variables. These results suggest that the cardiac reactivity plays a potentially important role in the link between blood pressure reactivity and hypertension and support the use of multivariate approaches to stress psychophysiology.
Salazar-Fraile, José; Ripoll-Alandes, Carmen; Bobes, Julio
2010-01-01
Although a high prevalence of personality disorders has been reported in substance users, the literature on their value for predicting treatment response is controversial. On the other hand, while the predictive validity of personality traits as predictors of response to drug abuse or dependence has been studied, research on the validity of narcissistic personality traits is scarce. To study the predictive value of personality disorders, narcissistic personality traits and self-esteem for predicting treatment response. We assessed 78 patients attended at an addiction treatment unit using personality disorder diagnoses and measures of self-esteem, narcissism and covert (hypersensitive) narcissism. These variables were used in a Cox survival model as predictive variables of time to relapse into drug use. Hypersensitive (covert) narcissism and borderline and passive-aggressive personality disorders were risk factors for relapse into drug use, while open narcissism was a protective factor. Self-esteem did not show predictive validity. Personality disorders characterized by impulsivity-instability and passivity-resentfulness show higher risk of relapse into drug abuse. Personality traits characterized by high sensitivity to humiliation increase the risk of relapse, whereas pride and self-confidence are protective factors.
NASA Astrophysics Data System (ADS)
Ganendran, L. B.; Sidhu, L. A.; Catchpole, E. A.; Chambers, L. E.; Dann, P.
2016-08-01
Seabirds are subject to the influences of local climate variables during periods of land-based activities such as breeding and, for some species, moult; particularly if they undergo a catastrophic moult (complete simultaneous moult) as do penguins. We investigated potential relationships between adult penguin survival and land-based climate variables (ambient air temperature, humidity and rainfall) using 46 years of mark-recapture data of little penguins Eudyptula minor gathered at a breeding colony on Phillip Island in southeastern Australia. Our results showed that adult penguin survival had a stronger association with land-based climate variables during the moult period, when birds were unable to go to sea for up to 3 weeks, than during the breeding period, when birds could sacrifice breeding success in favour of survival. Annual adult survival probability was positively associated with humidity during moult and negatively associated with rainfall during moult. Prolonged heat during breeding and moult had a negative association with annual adult survival. Local climate projections suggest increasing days of high temperatures, fewer days of rainfall which will result in more droughts (and by implication, lower humidity) and more extreme rainfall events. All of these predicted climate changes are expected to have a negative impact on adult penguin survival.
JCDSA: a joint covariate detection tool for survival analysis on tumor expression profiles.
Wu, Yiming; Liu, Yanan; Wang, Yueming; Shi, Yan; Zhao, Xudong
2018-05-29
Survival analysis on tumor expression profiles has always been a key issue for subsequent biological experimental validation. It is crucial how to select features which closely correspond to survival time. Furthermore, it is important how to select features which best discriminate between low-risk and high-risk group of patients. Common features derived from the two aspects may provide variable candidates for prognosis of cancer. Based on the provided two-step feature selection strategy, we develop a joint covariate detection tool for survival analysis on tumor expression profiles. Significant features, which are not only consistent with survival time but also associated with the categories of patients with different survival risks, are chosen. Using the miRNA expression data (Level 3) of 548 patients with glioblastoma multiforme (GBM) as an example, miRNA candidates for prognosis of cancer are selected. The reliability of selected miRNAs using this tool is demonstrated by 100 simulations. Furthermore, It is discovered that significant covariates are not directly composed of individually significant variables. Joint covariate detection provides a viewpoint for selecting variables which are not individually but jointly significant. Besides, it helps to select features which are not only consistent with survival time but also associated with prognosis risk. The software is available at http://bio-nefu.com/resource/jcdsa .
Ganendran, L B; Sidhu, L A; Catchpole, E A; Chambers, L E; Dann, P
2016-08-01
Seabirds are subject to the influences of local climate variables during periods of land-based activities such as breeding and, for some species, moult; particularly if they undergo a catastrophic moult (complete simultaneous moult) as do penguins. We investigated potential relationships between adult penguin survival and land-based climate variables (ambient air temperature, humidity and rainfall) using 46 years of mark-recapture data of little penguins Eudyptula minor gathered at a breeding colony on Phillip Island in southeastern Australia. Our results showed that adult penguin survival had a stronger association with land-based climate variables during the moult period, when birds were unable to go to sea for up to 3 weeks, than during the breeding period, when birds could sacrifice breeding success in favour of survival. Annual adult survival probability was positively associated with humidity during moult and negatively associated with rainfall during moult. Prolonged heat during breeding and moult had a negative association with annual adult survival. Local climate projections suggest increasing days of high temperatures, fewer days of rainfall which will result in more droughts (and by implication, lower humidity) and more extreme rainfall events. All of these predicted climate changes are expected to have a negative impact on adult penguin survival.
Gupta, Digant; Patel, Kamal; Lis, Christopher G
2015-09-04
We have previously reported that higher patient satisfaction (PS) with service quality is associated with favorable survival outcomes in a variety of cancers. However, we argued that patients with greater satisfaction might be the ones with better self-rated health (SRH), a recognized predictor of cancer survival. We therefore investigated whether SRH can supersede patient satisfaction as a predictor of survival in prostate cancer. Nine hundred seventeen prostate cancer treated at four Cancer Treatment Centers of America(®) hospitals between July 2011 and March 2013. PS was measured on a 7-point scale ranging from "completely dissatisfied" to "completely satisfied". SRH was measured on a 7-point scale ranging from "very poor" to "excellent". Both were dichotomized into two categories: top box response (7) versus all others (1-6). Patient survival was the primary end point. Cox regression was used to evaluate the association between PS and survival controlling for covariates. The response rate for this study was 72%. Majority of patients (n = 517) had stage II disease. Seven hundred eighty-seven (85.8%) patients were "completely satisfied". Three hundred nineteen (34.8%) patients had "excellent" SRH. There was a weak but significant correlation between satisfaction and SRH (Kendall's tau b = 0.18; p < 0.001). On univariate analysis, "completely satisfied" patients had a significantly lower risk of mortality (HR = 0.46; 95% CI: 0.25-0.85; p = 0.01). Similarly, patients with "excellent" SRH had a significantly lower risk of mortality (HR = 0.25; 95% CI: 0.11-0.58; p = 0.001). On multivariate analysis, SRH was found to be a significant predictor of survival (HR = 0.31; 95% CI: 0.12-0.79; p = 0.01) while patient satisfaction was not (HR = 0.76; 95% CI: 0.40-1.5; p = 0.40). SRH supersedes patient satisfaction with service quality as a predictor of survival in prostate cancer. SRH should be used as a control variable in analyses involving patient satisfaction as a predictor of clinical cancer outcomes.
Flynn, R Wesley; Scott, David E; Kuhne, Wendy; Soteropoulos, Diana; Lance, Stacey L
2015-03-01
Many metals are acutely toxic to aquatic organisms at high concentrations and for some metals, such as copper (Cu), even low-level chronic contamination may be cause for conservation concern. Amphibian susceptibility to Cu has been examined in only a few species, and susceptibility is highly variable. The lethal and sublethal effects were examined of chronic aqueous Cu exposure on embryonic and larval eastern narrowmouth toads, Gastrophryne carolinensis. Copper levels as low as 10 μg Cu/L reduced embryonic and larval survival. Embryonic survivorship varied within- and between-source populations, with embryos derived from uncontaminated-wetland parents having greater survival at lower Cu levels than embryos from parents from a metal-contaminated constructed wetland. At 30 μg/L, embryos from the contaminated site had greater survival. Overall survival from oviposition to metamorphosis was 68.9% at 0 μg/L and 5.4% at 10 μg/L. Similarly, embryos exposed to ≥50 μg/L demonstrated developmental delays in transition from embryo to free-swimming larva. These results demonstrate a negative population-specific response to environmentally relevant levels of Cu. © 2014 SETAC.
Metamorphosis of two amphibian species after chronic cadmium exposure in outdoor aquatic mesocosms
James, S.M.; Little, E.E.; Semlitsch, R.D.
2005-01-01
Amphibian larvae at contaminated sites may experience an alteration of metamorphic traits and survival compared to amphibians in uncontaminated conditions. Effects of chronic cadmium (Cd) exposure on the metamorphosis of American toads (Bufo americanus) and southern leopard frogs (Rana sphenocephala) were determined. The two species were reared separately from shortly after hatching through metamorphosis in outdoor mesocosms (1,325-L polyethylene cattle tanks) that simulated natural ponds and enhanced environmental realism relative to the laboratory. Both species exhibited a decrease in survival with increasing initial nominal aqueous Cd concentration. Cadmium treatment did not influence mass at metamorphosis for either species when survival was included as a covariate, but increased the age at metamorphosis for the American toads. The whole body Cd content of metamorphs increased with aqueous Cd treatment level for both species, and the American toads tended to possess more elevated residues. Cadmium quickly partitioned out of the water column and accumulated in and altered the abundance of the tadpoles' diet. Cadmium-contaminated sites may produce fewer metamorphs, and those that survive will metamorphose later and contain Cd. Interspecific differences in the response variables illustrate the importance of testing multiple species when assessing risk.
Thermal tolerance breadths among groundwater crustaceans living in a thermally constant environment.
Mermillod-Blondin, F; Lefour, C; Lalouette, L; Renault, D; Malard, F; Simon, L; Douady, C J
2013-05-01
The climate variability hypothesis assumes that the thermal tolerance breadth of a species is primarily determined by temperature variations experienced in its environment. If so, aquatic invertebrates living in thermally buffered environments would be expected to exhibit narrow thermal tolerance breadths (stenothermy). We tested this prediction by studying the thermal physiology of three isopods (Asellidae, Proasellus) colonizing groundwater habitats characterized by an annual temperature amplitude of less than 1°C. The species responses to temperature variation were assessed in the laboratory using five physiological variables: survival, locomotor activity, aerobic respiration, immune defense and concentrations of total free amino acids and sugars. The three species exhibited contrasted thermal physiologies, although all variables were not equally informative. In accordance with the climate variability hypothesis, two species were extremely sensitive even to moderate changes in temperature (2°C) below and above their habitat temperature. In contrast, the third species exhibited a surprisingly high thermal tolerance breadth (11°C). Differences in response to temperature variation among Proasellus species indicated that their thermal physiology was not solely shaped by the current temperature seasonality in their natural habitats. More particularly, recent gene flow among populations living in thermally constant yet contrasted habitats might explain the occurrence of eurytherm species in thermally buffered environments.
Weiser, Emily L.; Lanctot, Richard B.; Brown, Stephen C.; Gates, H. River; Bentzen, Rebecca L.; Bêty, Joël; Boldenow, Megan L.; English, Willow B.; Franks, Samantha E.; Koloski, Laura; Kwon, Eunbi; Lamarre, Jean-Francois; Lank, David B.; Liebezeit, Joseph R.; McKinnon, Laura; Nol, Erica; Rausch, Jennie; Saalfeld, Sarah T.; Senner, Nathan R.; Ward, David H.; Woodard, Paul F.; Sandercock, Brett K.
2018-01-01
Many Arctic shorebird populations are declining, and quantifying adult survival and the effects of anthropogenic factors is a crucial step toward a better understanding of population dynamics. We used a recently developed, spatially explicit Cormack–Jolly–Seber model in a Bayesian framework to obtain broad-scale estimates of true annual survival rates for 6 species of shorebirds at 9 breeding sites across the North American Arctic in 2010–2014. We tested for effects of environmental and ecological variables, study site, nest fate, and sex on annual survival rates of each species in the spatially explicit framework, which allowed us to distinguish between effects of variables on site fidelity versus true survival. Our spatially explicit analysis produced estimates of true survival rates that were substantially higher than previously published estimates of apparent survival for most species, ranging from S = 0.72 to 0.98 across 5 species. However, survival was lower for the arcticolasubspecies of Dunlin (Calidris alpina arcticola; S = 0.54), our only study taxon that migrates through the East Asian–Australasian Flyway. Like other species that use that flyway, arcticola Dunlin could be experiencing unsustainably low survival rates as a result of loss of migratory stopover habitat. Survival rates of our study species were not affected by timing of snowmelt or summer temperature, and only 2 species showed minor variation among study sites. Furthermore, although previous reproductive success, predator abundance, and the availability of alternative prey each affected survival of one species, no factors broadly affected survival across species. Overall, our findings of few effects of environmental or ecological variables suggest that annual survival rates of adult shorebirds are generally robust to conditions at Arctic breeding sites. Instead, conditions at migratory stopovers or overwintering sites might be driving adult survival rates and should be the focus of future studies.
Kumar, N B; Cantor, A; Allen, K; Cox, C E
2000-06-15
Although a large body of research exists concerning pathologic prognostic indicators of the rate of incidence and survival from breast carcinoma, to the authors' knowledge very few studies have examined the effects of anthropometric variables such as height, obesity, weight gain in adulthood, timing of weight gain, and body composition to survival, although these variables are related to the incidence rate. The survival status of 166 patients diagnosed with primary breast carcinoma and followed for at least 10 years was obtained from the Cancer Center's registry, and significant anthropometric and other known prognostic indicators regarding survival after diagnosis were determined by Cox proportional hazards analysis. Eighty-three of 166 breast carcinoma patients (50%) with up to 10 years of follow-up died of disease. Android body fat distribution, as indicated by a higher suprailiac:thigh ratio, was a statistically significant (P < 0.0001) prognostic indicator for survival after controlling for stage of disease, with a hazards ratio of 2.6 (95% confidence interval [95% CI], 1.63-4.17). Adult weight gain, as indicated specifically by weight at age 30 years, was a statistically significant (P < 0.05) prognostic indicator for survival with a hazards ratio of 1.15 (95% CI, 1.0-1.28). In addition, the authors observed the Quatelet Index, a negatively significant (P < 0.01) prognostic indicator for survival with a hazards ratio of 0.92 (95% CI, 0.87-0.98). Other markers of general obesity such as weight at diagnosis, percent body fat, and body surface area were not significant markers influencing survival. Similarly, height; triceps, biceps; subscapular, suprailiac, abdominal, and thigh skinfolds; waist and hip circumferences; family history; and reproductive and hormonal variables at the time of diagnosis showed no apparent significant relation to survival. The results of the current study provide some evidence that android body fat distribution at diagnosis and increased weight at age 30 years increases a woman's risk of dying of breast carcinoma. Copyright 2000 American Cancer Society.
Liver Transplantation for Fulminant Hepatic Failure
Farmer, Douglas G.; Anselmo, Dean M.; Ghobrial, R. Mark; Yersiz, Hasan; McDiarmid, Suzanne V.; Cao, Carlos; Weaver, Michael; Figueroa, Jesus; Khan, Khurram; Vargas, Jorge; Saab, Sammy; Han, Steven; Durazo, Francisco; Goldstein, Leonard; Holt, Curtis; Busuttil, Ronald W.
2003-01-01
Objective To analyze outcomes after liver transplantation (LT) in patients with fulminant hepatic failure (FHF) with emphasis on pretransplant variables that can potentially help predict posttransplant outcome. Summary Background Data FHF is a formidable clinical problem associated with a high mortality rate. While LT is the treatment of choice for irreversible FHF, few investigations have examined pretransplant variables that can potentially predict outcome after LT. Methods A retrospective review was undertaken of all patients undergoing LT for FHF at a single transplant center. The median follow-up was 41 months. Thirty-five variables were analyzed by univariate and multivariate analysis to determine their impact on patient and graft survival. Results Two hundred four patients (60% female, median age 20.2 years) required urgent LT for FHF. Before LT, the majority of patients were comatose (76%), on hemodialysis (16%), and ICU-bound. The 1- and 5-year survival rates were 73% and 67% (patient) and 63% and 57% (graft). The primary cause of patient death was sepsis, and the primary cause of graft failure was primary graft nonfunction. Univariate analysis of pre-LT variables revealed that 19 variables predicted survival. From these results, multivariate analysis determined that the serum creatinine was the single most important prognosticator of patient survival. Conclusions This study, representing one of the largest published series on LT for FHF, demonstrates a long-term survival of nearly 70% and develops a clinically applicable and readily measurable set of pretransplant factors that determine posttransplant outcome. PMID:12724633
Nicholson, Brian D; Mant, David; Neal, Richard D; Hart, Nigel; Hamilton, Willie; Shinkins, Bethany; Rubin, Greg; Rose, Peter W
2016-02-01
Variation in cancer survival persists between comparable nations and appears to be due, in part, to primary care practitioners (PCPs) having different thresholds for acting definitively in response to cancer-related symptoms. To explore whether cancer guidelines, and adherence to them, differ between jurisdictions and impacts on PCPs' propensity to take definitive action on cancer-related symptoms. A secondary analysis of survey data from six countries (10 jurisdictions) participating in the International Cancer Benchmarking Partnership. PCPs' responses to five clinical vignettes presenting symptoms and signs of lung (n = 2), colorectal (n = 2), and ovarian cancer (n = 1) were compared with investigation and referral recommendations in cancer guidelines. Nine jurisdictions had guidelines covering the two colorectal vignettes. For the lung vignettes, although eight jurisdictions had guidelines for the first, the second was covered by a Swedish guideline alone. Only the UK and Denmark had an ovarian cancer guideline. Survey responses of 2795 PCPs (crude response rate: 12%) were analysed. Guideline adherence ranged from 20-82%. UK adherence was lower than other jurisdictions for the lung vignette covered by the guidance (47% versus 58%; P <0.01) but similar (45% versus 46%) or higher (67% versus 38%; P <0.01) for the two colorectal vignettes. PCPs took definitive action least often when a guideline recommended a non-definitive action or made no recommendation. UK PCPs adhered to recommendations for definitive action less than their counterparts (P <0.01). There wasno association between jurisdictional guideline adherence and 1-year survival. Cancer guideline content is variable between similarly developed nations and poor guideline adherence does not explain differential survival. Guidelines that fail to cover high-risk presentations or that recommend non-definitive action may reduce definitive diagnostic action. © British Journal of General Practice 2016.
Kim, Youn H.; Tavallaee, Mahkam; Sundram, Uma; Salva, Katrin A.; Wood, Gary S.; Li, Shufeng; Rozati, Sima; Nagpal, Seema; Krathen, Michael; Reddy, Sunil; Hoppe, Richard T.; Nguyen-Lin, Annie; Weng, Wen-Kai; Armstrong, Randall; Pulitzer, Melissa; Advani, Ranjana H.; Horwitz, Steven M.
2015-01-01
Purpose In contrast to Hodgkin lymphoma and systemic anaplastic large-cell lymphoma, CD30 expression of malignant lymphocytes in mycosis fungoides (MF) and Sézary syndrome (SS) is quite variable. Clinical activity and safety of brentuximab vedotin, a CD30 targeting antibody-drug conjugate, was evaluated in MF and SS. Tissue and blood biomarkers of clinical response were explored. Patients and Methods In this phase II study, patients with MF or SS with negligible to 100% CD30 expression levels were treated with brentuximab vedotin (1.8 mg/kg) every 3 weeks for a maximum of sixteen doses. The primary end point was overall global response rate. Secondary end points included correlation of tissue CD30 expression level with clinical response, time to response, duration of response, progression-free and event-free survivals, and safety. Results Of the 32 patients enrolled and treated, 30 patients had available efficacy evaluations. Objective global response was observed in 21 (70%) of 30 patients (90% CI, 53% to 83%). CD30 expression assessed by immunohistochemistry was highly variable, with a median CD30max of 13% (range, 0% to 100%). Those with <5% CD30 expression had a lower likelihood of global response than did those with 5% or greater CD30 expression (P < .005). CD163 positive tumor-associated macrophages, many of which coexpress CD30, were abundant in tissue. Peripheral neuropathy was the most common adverse event. Conclusion Brentuximab vedotin demonstrated significant clinical activity in treatment-refractory or advanced MF or SS with a wide range of CD30 expression levels. Additional biomarker studies may help optimize rational design of combination therapies with brentuximab vedotin. PMID:26195720
Dim light at night disrupts the short-day response in Siberian hamsters.
Ikeno, Tomoko; Weil, Zachary M; Nelson, Randy J
2014-02-01
Photoperiodic regulation of physiology, morphology, and behavior is crucial for many animals to survive seasonally variable conditions unfavorable for reproduction and survival. The photoperiodic response in mammals is mediated by nocturnal secretion of melatonin under the control of a circadian clock. However, artificial light at night caused by recent urbanization may disrupt the circadian clock, as well as the photoperiodic response by blunting melatonin secretion. Here we examined the effect of dim light at night (dLAN) (5lux of light during the dark phase) on locomotor activity rhythms and short-day regulation of reproduction, body mass, pelage properties, and immune responses of male Siberian hamsters. Short-day animals reduced gonadal and body mass, decreased spermatid nuclei and sperm numbers, molted to a whiter pelage, and increased pelage density compared to long-day animals. However, animals that experienced short days with dLAN did not show these short-day responses. Moreover, short-day specific immune responses were altered in dLAN conditions. The nocturnal activity pattern was blunted in dLAN hamsters, consistent with the observation that dLAN changed expression of the circadian clock gene, Period1. In addition, we demonstrated that expression levels of genes implicated in the photoperiodic response, Mel-1a melatonin receptor, Eyes absent 3, thyroid stimulating hormone receptor, gonadotropin-releasing hormone, and gonadotropin-inhibitory hormone, were higher in dLAN animals than those in short-day animals. These results suggest that dLAN disturbs the circadian clock function and affects the molecular mechanisms of the photoperiodic response. Copyright © 2013 Elsevier Inc. All rights reserved.
Somatic Mutations and Clonal Hematopoiesis in Aplastic Anemia.
Yoshizato, Tetsuichi; Dumitriu, Bogdan; Hosokawa, Kohei; Makishima, Hideki; Yoshida, Kenichi; Townsley, Danielle; Sato-Otsubo, Aiko; Sato, Yusuke; Liu, Delong; Suzuki, Hiromichi; Wu, Colin O; Shiraishi, Yuichi; Clemente, Michael J; Kataoka, Keisuke; Shiozawa, Yusuke; Okuno, Yusuke; Chiba, Kenichi; Tanaka, Hiroko; Nagata, Yasunobu; Katagiri, Takamasa; Kon, Ayana; Sanada, Masashi; Scheinberg, Phillip; Miyano, Satoru; Maciejewski, Jaroslaw P; Nakao, Shinji; Young, Neal S; Ogawa, Seishi
2015-07-02
In patients with acquired aplastic anemia, destruction of hematopoietic cells by the immune system leads to pancytopenia. Patients have a response to immunosuppressive therapy, but myelodysplastic syndromes and acute myeloid leukemia develop in about 15% of the patients, usually many months to years after the diagnosis of aplastic anemia. We performed next-generation sequencing and array-based karyotyping using 668 blood samples obtained from 439 patients with aplastic anemia. We analyzed serial samples obtained from 82 patients. Somatic mutations in myeloid cancer candidate genes were present in one third of the patients, in a limited number of genes and at low initial variant allele frequency. Clonal hematopoiesis was detected in 47% of the patients, most frequently as acquired mutations. The prevalence of the mutations increased with age, and mutations had an age-related signature. DNMT3A-mutated and ASXL1-mutated clones tended to increase in size over time; the size of BCOR- and BCORL1-mutated and PIGA-mutated clones decreased or remained stable. Mutations in PIGA and BCOR and BCORL1 correlated with a better response to immunosuppressive therapy and longer and a higher rate of overall and progression-free survival; mutations in a subgroup of genes that included DNMT3A and ASXL1 were associated with worse outcomes. However, clonal dynamics were highly variable and might not necessarily have predicted the response to therapy and long-term survival among individual patients. Clonal hematopoiesis was prevalent in aplastic anemia. Some mutations were related to clinical outcomes. A highly biased set of mutations is evidence of Darwinian selection in the failed bone marrow environment. The pattern of somatic clones in individual patients over time was variable and frequently unpredictable. (Funded by Grant-in-Aid for Scientific Research and others.).
Prescott, Anna T; Hull, Jay G; Dionne-Odom, J Nicholas; Tosteson, Tor D; Lyons, Kathleen Doyle; Li, Zhigang; Li, Zhongze; Dragnev, Konstantin H; Hegel, Mark T; Steinhauser, Karen E; Ahles, Tim A; Bakitas, Marie A
2017-12-01
Randomized controlled trials (RCTs) of early palliative care interventions in advanced cancer have positively impacted patient survival, yet the mechanisms remain unknown. This secondary analysis of 2 RCTs assessed whether an early palliative care intervention moderates the relationship between depressive symptoms and survival. The relationships among mood, survival, and early palliative care intervention were studied among 529 advanced cancer patients who participated in 2 RCTs. The first (N = 322) compared intervention versus usual care. The second (N = 207) compared early versus delayed intervention (12 weeks after enrollment). The interventions included an in-person consultation, weekly nurse coach-facilitated phone sessions, and monthly follow-up. Mood was measured using the Center for Epidemiologic Studies-Depression (CES-D) scale. Cox proportional hazard analyses were used to examine the effects of baseline CES-D scores, the intervention, and their interaction on mortality risk while controlling for demographic variables, cancer site, and illness severity. The combined sample was 56% male (M = 64.7 years). Higher baseline CES-D scores were significantly associated with greater mortality risk (hazard ratio [HR] = 1.042, 95% confidence interval [CI] [1.017, 1.067], p = .001). However, participants with higher CES-D scores who received the intervention had a lower mortality risk (HR = .963, CI [0.933, 0.993], p = .018) even when controlling for demographics, cancer site, and illness-related variables. This study is the first to demonstrate that patients with advanced cancer who also have depressive symptoms benefit the most from early palliative care. Future research should be devoted to exploring the mechanisms responsible for these relationships. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
CASAS: Cancer Survival Analysis Suite, a web based application
Rupji, Manali; Zhang, Xinyan; Kowalski, Jeanne
2017-01-01
We present CASAS, a shiny R based tool for interactive survival analysis and visualization of results. The tool provides a web-based one stop shop to perform the following types of survival analysis: quantile, landmark and competing risks, in addition to standard survival analysis. The interface makes it easy to perform such survival analyses and obtain results using the interactive Kaplan-Meier and cumulative incidence plots. Univariate analysis can be performed on one or several user specified variable(s) simultaneously, the results of which are displayed in a single table that includes log rank p-values and hazard ratios along with their significance. For several quantile survival analyses from multiple cancer types, a single summary grid is constructed. The CASAS package has been implemented in R and is available via http://shinygispa.winship.emory.edu/CASAS/. The developmental repository is available at https://github.com/manalirupji/CASAS/. PMID:28928946
CASAS: Cancer Survival Analysis Suite, a web based application.
Rupji, Manali; Zhang, Xinyan; Kowalski, Jeanne
2017-01-01
We present CASAS, a shiny R based tool for interactive survival analysis and visualization of results. The tool provides a web-based one stop shop to perform the following types of survival analysis: quantile, landmark and competing risks, in addition to standard survival analysis. The interface makes it easy to perform such survival analyses and obtain results using the interactive Kaplan-Meier and cumulative incidence plots. Univariate analysis can be performed on one or several user specified variable(s) simultaneously, the results of which are displayed in a single table that includes log rank p-values and hazard ratios along with their significance. For several quantile survival analyses from multiple cancer types, a single summary grid is constructed. The CASAS package has been implemented in R and is available via http://shinygispa.winship.emory.edu/CASAS/. The developmental repository is available at https://github.com/manalirupji/CASAS/.
Koyama, Kento; Hokunan, Hidekazu; Hasegawa, Mayumi; Kawamura, Shuso
2016-01-01
ABSTRACT Despite effective inactivation procedures, small numbers of bacterial cells may still remain in food samples. The risk that bacteria will survive these procedures has not been estimated precisely because deterministic models cannot be used to describe the uncertain behavior of bacterial populations. We used the Poisson distribution as a representative probability distribution to estimate the variability in bacterial numbers during the inactivation process. Strains of four serotypes of Salmonella enterica, three serotypes of enterohemorrhagic Escherichia coli, and one serotype of Listeria monocytogenes were evaluated for survival. We prepared bacterial cell numbers following a Poisson distribution (indicated by the parameter λ, which was equal to 2) and plated the cells in 96-well microplates, which were stored in a desiccated environment at 10% to 20% relative humidity and at 5, 15, and 25°C. The survival or death of the bacterial cells in each well was confirmed by adding tryptic soy broth as an enrichment culture. Changes in the Poisson distribution parameter during the inactivation process, which represent the variability in the numbers of surviving bacteria, were described by nonlinear regression with an exponential function based on a Weibull distribution. We also examined random changes in the number of surviving bacteria using a random number generator and computer simulations to determine whether the number of surviving bacteria followed a Poisson distribution during the bacterial death process by use of the Poisson process. For small initial cell numbers, more than 80% of the simulated distributions (λ = 2 or 10) followed a Poisson distribution. The results demonstrate that variability in the number of surviving bacteria can be described as a Poisson distribution by use of the model developed by use of the Poisson process. IMPORTANCE We developed a model to enable the quantitative assessment of bacterial survivors of inactivation procedures because the presence of even one bacterium can cause foodborne disease. The results demonstrate that the variability in the numbers of surviving bacteria was described as a Poisson distribution by use of the model developed by use of the Poisson process. Description of the number of surviving bacteria as a probability distribution rather than as the point estimates used in a deterministic approach can provide a more realistic estimation of risk. The probability model should be useful for estimating the quantitative risk of bacterial survival during inactivation. PMID:27940547
Koyama, Kento; Hokunan, Hidekazu; Hasegawa, Mayumi; Kawamura, Shuso; Koseki, Shigenobu
2017-02-15
Despite effective inactivation procedures, small numbers of bacterial cells may still remain in food samples. The risk that bacteria will survive these procedures has not been estimated precisely because deterministic models cannot be used to describe the uncertain behavior of bacterial populations. We used the Poisson distribution as a representative probability distribution to estimate the variability in bacterial numbers during the inactivation process. Strains of four serotypes of Salmonella enterica, three serotypes of enterohemorrhagic Escherichia coli, and one serotype of Listeria monocytogenes were evaluated for survival. We prepared bacterial cell numbers following a Poisson distribution (indicated by the parameter λ, which was equal to 2) and plated the cells in 96-well microplates, which were stored in a desiccated environment at 10% to 20% relative humidity and at 5, 15, and 25°C. The survival or death of the bacterial cells in each well was confirmed by adding tryptic soy broth as an enrichment culture. Changes in the Poisson distribution parameter during the inactivation process, which represent the variability in the numbers of surviving bacteria, were described by nonlinear regression with an exponential function based on a Weibull distribution. We also examined random changes in the number of surviving bacteria using a random number generator and computer simulations to determine whether the number of surviving bacteria followed a Poisson distribution during the bacterial death process by use of the Poisson process. For small initial cell numbers, more than 80% of the simulated distributions (λ = 2 or 10) followed a Poisson distribution. The results demonstrate that variability in the number of surviving bacteria can be described as a Poisson distribution by use of the model developed by use of the Poisson process. We developed a model to enable the quantitative assessment of bacterial survivors of inactivation procedures because the presence of even one bacterium can cause foodborne disease. The results demonstrate that the variability in the numbers of surviving bacteria was described as a Poisson distribution by use of the model developed by use of the Poisson process. Description of the number of surviving bacteria as a probability distribution rather than as the point estimates used in a deterministic approach can provide a more realistic estimation of risk. The probability model should be useful for estimating the quantitative risk of bacterial survival during inactivation. Copyright © 2017 Koyama et al.
Evaluation of stream flow effects on smolt survival in the Yakima River basin, Washington
Courter,; Garrison,; Kock, Tobias J.; Perry, Russell W.
2012-01-01
Yearling Chinook smolt survival and travel time estimates from 2012 suggest that migration rates and survival rates in the Roza Reach may be associated with stream flow, water temperature, release timing (i.e. migratory disposition), and fish size, but the extent to which each variable influenced survival is yet to be determined. The lowest survival rate (61%) and longest travel time (median 2.26 days) was observed in Release Group 1, which had the smallest size distribution and experienced the lowest flows, lowest temperatures, and earliest release date among the three groups. Release Groups 2 and 3 survived at 96% and 98% respectively and traveled through the Roza Reach in less than eight hours. The primary focus of years two and three of this study will be to collect data that minimizes the effect of confounding explanatory variables, so that flow effects on emigration survival can be quantified independent of these other influential factors.
Modeling the survival kinetics of Salmonella in tree nuts for use in risk assessment.
Santillana Farakos, Sofia M; Pouillot, Régis; Anderson, Nathan; Johnson, Rhoma; Son, Insook; Van Doren, Jane
2016-06-16
Salmonella has been shown to survive in tree nuts over long periods of time. This survival capacity and its variability are key elements for risk assessment of Salmonella in tree nuts. The aim of this study was to develop a mathematical model to predict survival of Salmonella in tree nuts at ambient storage temperatures that considers variability and uncertainty separately and can easily be incorporated into a risk assessment model. Data on Salmonella survival on raw almonds, pecans, pistachios and walnuts were collected from the peer reviewed literature. The Weibull model was chosen as the baseline model and various fixed effect and mixed effect models were fit to the data. The best model identified through statistical analysis testing was then used to develop a hierarchical Bayesian model. Salmonella in tree nuts showed slow declines at temperatures ranging from 21°C to 24°C. A high degree of variability in survival was observed across tree nut studies reported in the literature. Statistical analysis results indicated that the best applicable model was a mixed effect model that included a fixed and random variation of δ per tree nut (which is the time it takes for the first log10 reduction) and a fixed variation of ρ per tree nut (parameter which defines the shape of the curve). Higher estimated survival rates (δ) were obtained for Salmonella on pistachios, followed in decreasing order by pecans, almonds and walnuts. The posterior distributions obtained from Bayesian inference were used to estimate the variability in the log10 decrease levels in survival for each tree nut, and the uncertainty of these estimates. These modeled uncertainty and variability distributions of the estimates can be used to obtain a complete exposure assessment of Salmonella in tree nuts when including time-temperature parameters for storage and consumption data. The statistical approach presented in this study may be applied to any studies that aim to develop predictive models to be implemented in a probabilistic exposure assessment or a quantitative microbial risk assessment. Published by Elsevier B.V.
Lunkenheimer, Erika; Lichtwarck-Aschoff, Anna; Hollenstein, Tom; Kemp, Christine J.; Granic, Isabela
2016-01-01
Objective Parent-child coercive cycles have been associated with both rigidity and inconsistency in parenting behavior. To explain these mixed findings, we examined real-time variability in maternal responses to children's off-task behavior to determine whether this common trigger of the coercive cycle (responding to child misbehavior) is associated with rigidity or inconsistency in parenting. We also examined the effects of risk factors for coercion (maternal hostility, maternal depressive symptoms, child externalizing problems, and dyadic negativity) on patterns of parenting. Design Mother-child dyads (N = 96; M child age = 41 months) completed a difficult puzzle task, and observations were coded continuously for parent (e.g., directive, teaching) and child behavior (e.g., on-task, off-task). Results Multilevel continuous-time survival analyses revealed that parenting behavior is less variable when children are off-task. However, when risk factors are higher, a different profile emerges. Combined maternal and child risk is associated with markedly lower variability in parenting behavior overall (i.e., rigidity) paired with shifts towards higher variability specifically when children are off-task (i.e., inconsistency). Dyadic negativity (i.e., episodes when children are off-task and parents engage in negative behavior) are also associated with higher parenting variability. Conclusions Risk factors confer rigidity in parenting overall, but in moments when higher-risk parents must respond to child misbehavior, their parenting becomes more variable, suggesting inconsistency and ineffectiveness. This context-dependent shift in parenting behavior may help explain prior mixed findings and offer new directions for family interventions designed to reduce coercive processes. PMID:28190978
Dazard, Jean-Eudes; Ishwaran, Hemant; Mehlotra, Rajeev; Weinberg, Aaron; Zimmerman, Peter
2018-01-01
Unraveling interactions among variables such as genetic, clinical, demographic and environmental factors is essential to understand the development of common and complex diseases. To increase the power to detect such variables interactions associated with clinical time-to-events outcomes, we borrowed established concepts from random survival forest (RSF) models. We introduce a novel RSF-based pairwise interaction estimator and derive a randomization method with bootstrap confidence intervals for inferring interaction significance. Using various linear and nonlinear time-to-events survival models in simulation studies, we first show the efficiency of our approach: true pairwise interaction-effects between variables are uncovered, while they may not be accompanied with their corresponding main-effects, and may not be detected by standard semi-parametric regression modeling and test statistics used in survival analysis. Moreover, using a RSF-based cross-validation scheme for generating prediction estimators, we show that informative predictors may be inferred. We applied our approach to an HIV cohort study recording key host gene polymorphisms and their association with HIV change of tropism or AIDS progression. Altogether, this shows how linear or nonlinear pairwise statistical interactions of variables may be efficiently detected with a predictive value in observational studies with time-to-event outcomes. PMID:29453930
Dazard, Jean-Eudes; Ishwaran, Hemant; Mehlotra, Rajeev; Weinberg, Aaron; Zimmerman, Peter
2018-02-17
Unraveling interactions among variables such as genetic, clinical, demographic and environmental factors is essential to understand the development of common and complex diseases. To increase the power to detect such variables interactions associated with clinical time-to-events outcomes, we borrowed established concepts from random survival forest (RSF) models. We introduce a novel RSF-based pairwise interaction estimator and derive a randomization method with bootstrap confidence intervals for inferring interaction significance. Using various linear and nonlinear time-to-events survival models in simulation studies, we first show the efficiency of our approach: true pairwise interaction-effects between variables are uncovered, while they may not be accompanied with their corresponding main-effects, and may not be detected by standard semi-parametric regression modeling and test statistics used in survival analysis. Moreover, using a RSF-based cross-validation scheme for generating prediction estimators, we show that informative predictors may be inferred. We applied our approach to an HIV cohort study recording key host gene polymorphisms and their association with HIV change of tropism or AIDS progression. Altogether, this shows how linear or nonlinear pairwise statistical interactions of variables may be efficiently detected with a predictive value in observational studies with time-to-event outcomes.
Local weather, regional climate, and annual survival of the northern spotted owl
Glenn, E.M.; Anthony, R.G.; Forsman, E.D.; Olson, G.S.
2011-01-01
We used an information-theoretical approach and Cormack-Jolly-Seber models for open populations in program MARK to examine relationships between survival rates of Northern Spotted Owls and a variety of local weather variables and long-term climate variables. In four of the six populations examined, survival was positively associated with wetter than normal conditions during the growing season or high summer temperatures. At the three study areas located at the highest elevations, survival was positively associated with winter temperature but also had a negative or quadratic relation with the number of storms and winter precipitation. A metaanalysis of all six areas combined indicated that annual survival was most strongly associated with phase shifts in the Southern Oscillation and Pacific Decadal Oscillation, which reflect large-scale temperature and precipitation patterns in this region. Climate accounted for a variable amount (1-41%) of the total process variation in annual survival but for more year-to-year variation (3-66%) than did spatial variation among owl territories (0-7%). Negative associations between survival and cold, wet winters and nesting seasons were similar to those found in other studies of the Spotted Owl. The relationships between survival and growing-season precipitation and regional climate patterns, however, had not been reported for this species previously. Climate-change models for the first half of the 21st century predict warmer, wetter winters and hotter, drier summers for the Pacific Northwest. Our results indicate that these conditions could decrease Spotted Owl survival in some areas. Copyright ?? The Cooper Ornithological Society 2011.
Baili, Paolo; Di Salvo, Francesca; Marcos-Gragera, Rafael; Siesling, Sabine; Mallone, Sandra; Santaquilani, Mariano; Micheli, Andrea; Lillini, Roberto; Francisci, Silvia
2015-10-01
Overall survival after cancer is frequently used when assessing a health care service's performance as a whole. It is mainly used by the public, politicians and the media, and is often dismissed by clinicians because of the heterogeneous mix of different cancers, risk factors and treatment modalities. Here we give survival details for all cancers combined in Europe, correlating it with economic variables to suggest reasons for differences. We computed age and cancer site case-mix standardised relative survival for all cancers combined (ACRS) for 29 countries participating in the EUROCARE-5 project with data on more than 7.5million cancer cases from 87 population-based cancer registries, using complete and period approach. Denmark, United Kingdom (UK) and Eastern European countries had lower survival than neighbouring countries. Five-year ACRS has been increasing throughout Europe, and substantial increases, between 1999-2001 and 2005-2007, have been achieved in countries where survival was lower in the past. Five-year ACRS for men and women are positively correlated with macro-economic variables like the Gross Domestic Product (GDP) and Total National Expenditure on Health (TNEH) (R 2 about 70%). Countries with recent larger increases in GDP and TNEH had greater increases in cancer survival. ACRS serves to compare all cancer survival in Europe taking account of the geographical variability in case-mixes. The EUROCARE-5 data on ACRS confirm previous EUROCARE findings. Survival appears to correlate with macro-economic determinants, particularly with investments in the health care system. Copyright © 2015 Elsevier Ltd. All rights reserved.
Uttley, M; Crawford, M H
1994-02-01
In 1980 and 1981 Mennonite descendants of a group of Russian immigrants participated in a multidisciplinary study of biological aging. The Mennonites live in Goessel, Kansas, and Henderson, Nebraska. In 1991 the survival status of the participants was documented by each church secretary. Data are available for 1009 individuals, 177 of whom are now deceased. They ranged from 20 to 95 years in age when the data were collected. Biological ages were computed using a stepwise multiple regression procedure based on 38 variables previously identified as being related to survival, with chronological age as the dependent variable. Standardized residuals place participants in either a predicted-younger or a predicted-older group. The independence of the variables biological age and survival status is tested with the chi-square statistic. The significance of biological age differences between surviving and deceased Mennonites is determined by t test values. The two statistics provide consistent results. Predicted age group classification and survival status are related. The group of deceased participants is generally predicted to be older than the group of surviving participants, although neither statistic is significant for all subgroups of Mennonites. In most cases, however, individuals in the predicted-older groups are at a relatively higher risk of dying compared with those in the predicted-younger groups, although the increased risk is not always significant.
Moschino, Vanessa; Delaney, Eugenia; Meneghetti, Francesca; Ros, Luisa Da
2011-06-01
Transplanted Mytilus galloprovincialis and native Ruditapes philippinarum were deployed in 10 sampling stations with different pollution impact within the Lagoon of Venice to evaluate the temporal variations and the suitability of the following cytochemical and histochemical biomarkers just as indicators of environmental stress: lysosomal membrane stability, lipofuscins, neutral lipids and lysosome to cytoplasm volume ratio. The physiological status of the organisms was also investigated by determining the survival in air capability and the reburrowing rate (clams). The biological parameters were assessed in June and October. Furthermore, for a better definition of the environmental aspects of the study sites, heavy metal, PAH and PCB concentrations were also evaluated in the sediments. As a whole, the biological responses examined in both species from all the sampling sites showed significant differences between the two seasonal campaigns, only lysosomal membrane stability exhibited less variability. Pollutants in sediments generally showed low-intermediate contamination levels, few hotspots persisting mostly in the inner areas of the lagoon, the most influenced by the industrial zone. Transplanted mussels were more responsive than native clams and the biological responses of both species varied temporally. The range of the spatial variability was always narrow and reflected only partially the broader variability shown by the chemical content in the sediments. In this sense, biological responses seemed to be particularly influenced by the high temporal and spatial heterogeneity that characterise the Lagoon of Venice, as well as most of the transitional environments.
Esque, Todd C.; Medica, Phil A.; Shryock, Daniel F.; Defalco, Lesley A.; Webb, Robert H.; Hunter, Richard B.
2015-01-01
• Conclusions: A rare establishment event for Y. brevifolia during 1983–1984, triggered by above-average summer rainfall, provided a unique opportunity to track early survival and growth. Infrequent but acute episodes of herbivory during drought influenced demography for decades. Variability in survival among young Y. brevifolia indicates that size-dependent demographic variables will improve forecasts for this long-lived desert species under predicted regional climate change.
Individual-tree probability of survival model for the Northeastern United States
Richard M. Teck; Donald E. Hilt
1990-01-01
Describes a distance-independent individual-free probability of survival model for the Northeastern United States. Survival is predicted using a sixparameter logistic function with species-specific coefficients. Coefficients are presented for 28 species groups. The model accounts for variability in annual survival due to species, tree size, site quality, and the tree...
Morales-Buenrostro, Luis E; Marino-Vázquez, Lluvia A; Alberú, Josefina
2009-01-01
This is a retrospective study that includes four decades of kidney transplant program at our Institute, with a total of 923 kidney transplants in 872 recipients. In this report, the effect of variables in recipient, donor, and transplant on long-term graft survival was analyzed using the Kaplan Meier method with log-rank test for survival comparisons. Global graft survival at our center-analyzed by censoring for death-with-functioning-graft-for 1, 5 and 10 years was 93%, 83% and 74%, respectively, with median survival of 24.5 years. When analyzed for all-cause graft loss, 1, 5 and 10 year survival was 90%, 76% and 61%, with 12.8-year median survival. Variables associated with lower graft survival censored for death-with-functioning-graft were transplantation in an earlier decade, less histocompatibility, younger kidney transplant recipients, no induction therapy, and double drug initial immunosuppression. After Cox's regression multivariate analysis, the risk factors that remained associated with worse survival were younger recipient, earlier transplant decade, and deceased donor.
Fatigue of restorative materials.
Baran, G; Boberick, K; McCool, J
2001-01-01
Failure due to fatigue manifests itself in dental prostheses and restorations as wear, fractured margins, delaminated coatings, and bulk fracture. Mechanisms responsible for fatigue-induced failure depend on material ductility: Brittle materials are susceptible to catastrophic failure, while ductile materials utilize their plasticity to reduce stress concentrations at the crack tip. Because of the expense associated with the replacement of failed restorations, there is a strong desire on the part of basic scientists and clinicians to evaluate the resistance of materials to fatigue in laboratory tests. Test variables include fatigue-loading mode and test environment, such as soaking in water. The outcome variable is typically fracture strength, and these data typically fit the Weibull distribution. Analysis of fatigue data permits predictive inferences to be made concerning the survival of structures fabricated from restorative materials under specified loading conditions. Although many dental-restorative materials are routinely evaluated, only limited use has been made of fatigue data collected in vitro: Wear of materials and the survival of porcelain restorations has been modeled by both fracture mechanics and probabilistic approaches. A need still exists for a clinical failure database and for the development of valid test methods for the evaluation of composite materials.
NASA Astrophysics Data System (ADS)
Giménez, Luis
2002-12-01
Chasmagnathus granulata is a South American crab occurring in estuarine salt marshes of the Brazilian, Uruguayan and Argentine coasts. Life history is characterized by an export strategy of its larval stages. I reviewed information on experimental manipulation of salinity during embryonic and larval development (pre- and posthatching salinities), and on habitat characteristics of C. granulata in order to determine potential effects of larval response to salinity in the field and to suggest consequences for the population structure. Local populations are spread over coastal areas with different physical characteristics. Benthic phases occupy estuaries characterized by different patterns of salinity variation, and release larvae to coastal waters characterized by strong salinity gradients. The zoea 1 of C. granulata showed a strong acclimatory response to low salinity. This response operated only during the first weeks of development (during zoeae 1 and 2) since subsequent larval survival at low posthatching salinities was consistently low. Larvae developing at low salinity frequently followed a developmental pathway with five instead of four zoeal stages. The ability to acclimate and the variability in larval development (i.e. the existence of alternative developmental pathways) could be interpreted as a strategy to buffer environmental variability at spatial scales of local or population networks. Early survivorship and production of larvae may be relatively high across a rather wide range of variability in salinity (5-32‰). Plastic responses to low salinity would therefore contribute to maintain a certain degree of population connectivity and persistence regardless of habitat heterogeneity.
NASA Astrophysics Data System (ADS)
Giménez, Luis
2003-01-01
Chasmagnathus granulata is a South American crab occurring in estuarine salt marshes of the Brazilian, Uruguayan and Argentine coasts. Life history is characterized by an export strategy of its larval stages. I reviewed information on experimental manipulation of salinity during embryonic and larval development (pre- and posthatching salinities), and on habitat characteristics of C. granulata in order to determine potential effects of larval response to salinity in the field and to suggest consequences for the population structure. Local populations are spread over coastal areas with different physical characteristics. Benthic phases occupy estuaries characterized by different patterns of salinity variation, and release larvae to coastal waters characterized by strong salinity gradients. The zoea 1 of C. granulata showed a strong acclimatory response to low salinity. This response operated only during the first weeks of development (during zoeae 1 and 2) since subsequent larval survival at low posthatching salinities was consistently low. Larvae developing at low salinity frequently followed a developmental pathway with five instead of four zoeal stages. The ability to acclimate and the variability in larval development (i.e. the existence of alternative developmental pathways) could be interpreted as a strategy to buffer environmental variability at spatial scales of local or population networks. Early survivorship and production of larvae may be relatively high across a rather wide range of variability in salinity (5-32‰). Plastic responses to low salinity would therefore contribute to maintain a certain degree of population connectivity and persistence regardless of habitat heterogeneity.
Coates, Peter S.; Brussee, Brianne E.; Ricca, Mark A.; Dudko, Jonathan E.; Prochazka, Brian G.; Espinosa, Shawn P.; Casazza, Michael L.; Delehanty, David J.
2017-08-10
Greater sage-grouse (Centrocercus urophasianus; hereinafter, "sage-grouse") are highly dependent on sagebrush (Artemisia spp.) dominated vegetation communities for food and cover from predators. Although this species requires the presence of sagebrush shrubs in the overstory, it also inhabits a broad geographic distribution with significant gradients in precipitation and temperature that drive variation in sagebrush ecosystem structure and concomitant shrub understory conditions. Variability in understory conditions across the species’ range may be responsible for the sometimes contradictory findings in the scientific literature describing sage-grouse habitat use and selection during important life history stages, such as nesting. To help understand the importance of this variability and to help guide management actions, we evaluated the nesting and brood-rearing microhabitat factors that influence selection and survival patterns in the Great Basin using a large dataset of microhabitat characteristics from study areas spanning northern Nevada and a portion of northeastern California from 2009 to 2016. The spatial and temporal coverage of the dataset provided a powerful opportunity to evaluate microhabitat factors important to sage-grouse reproduction, while also considering habitat variation associated with different climatic conditions and areas affected by wildfire. The summary statistics for numerous microhabitat factors, and the strength of their association with sage-grouse habitat selection and survival, are provided in this report to support decisions by land managers, policy-makers, and others with the best-available science in a timely manner.
NASA Astrophysics Data System (ADS)
Towler, Erin; Saab, Victoria A.; Sojda, Richard S.; Dickinson, Katherine; Bruyère, Cindy L.; Newlon, Karen R.
2012-12-01
Given the projected threat that climate change poses to biodiversity, the need for proactive response efforts is clear. However, integrating uncertain climate change information into conservation planning is challenging, and more explicit guidance is needed. To this end, this article provides a specific example of how a risk-based approach can be used to incorporate a species' response to climate into conservation decisions. This is shown by taking advantage of species' response (i.e., impact) models that have been developed for a well-studied bird species of conservation concern. Specifically, we examine the current and potential impact of climate on nest survival of the Lewis's Woodpecker ( Melanerpes lewis) in two different habitats. To address climate uncertainty, climate scenarios are developed by manipulating historical weather observations to create ensembles (i.e., multiple sequences of daily weather) that reflect historical variability and potential climate change. These ensembles allow for a probabilistic evaluation of the risk posed to Lewis's Woodpecker nest survival and are used in two demographic analyses. First, the relative value of each habitat is compared in terms of nest survival, and second, the likelihood of exceeding a critical population threshold is examined. By embedding the analyses in a risk framework, we show how management choices can be made to be commensurate with a defined level of acceptable risk. The results can be used to inform habitat prioritization and are discussed in the context of an economic framework for evaluating trade-offs between management alternatives.
Towler, Erin; Saab, Victoria A.; Sojda, Richard S.; Dickinson, Katherine; Bruyere, Cindy L.; Newlon, Karen R.
2012-01-01
Given the projected threat that climate change poses to biodiversity, the need for proactive response efforts is clear. However, integrating uncertain climate change information into conservation planning is challenging, and more explicit guidance is needed. To this end, this article provides a specific example of how a risk-based approach can be used to incorporate a species' response to climate into conservation decisions. This is shown by taking advantage of species' response (i.e., impact) models that have been developed for a well-studied bird species of conservation concern. Specifically, we examine the current and potential impact of climate on nest survival of the Lewis's Woodpecker (Melanerpes lewis) in two different habitats. To address climate uncertainty, climate scenarios are developed by manipulating historical weather observations to create ensembles (i.e., multiple sequences of daily weather) that reflect historical variability and potential climate change. These ensembles allow for a probabilistic evaluation of the risk posed to Lewis's Woodpecker nest survival and are used in two demographic analyses. First, the relative value of each habitat is compared in terms of nest survival, and second, the likelihood of exceeding a critical population threshold is examined. By embedding the analyses in a risk framework, we show how management choices can be made to be commensurate with a defined level of acceptable risk. The results can be used to inform habitat prioritization and are discussed in the context of an economic framework for evaluating trade-offs between management alternatives.
Oztekin, Asil; Delen, Dursun; Kong, Zhenyu James
2009-12-01
Predicting the survival of heart-lung transplant patients has the potential to play a critical role in understanding and improving the matching procedure between the recipient and graft. Although voluminous data related to the transplantation procedures is being collected and stored, only a small subset of the predictive factors has been used in modeling heart-lung transplantation outcomes. The previous studies have mainly focused on applying statistical techniques to a small set of factors selected by the domain-experts in order to reveal the simple linear relationships between the factors and survival. The collection of methods known as 'data mining' offers significant advantages over conventional statistical techniques in dealing with the latter's limitations such as normality assumption of observations, independence of observations from each other, and linearity of the relationship between the observations and the output measure(s). There are statistical methods that overcome these limitations. Yet, they are computationally more expensive and do not provide fast and flexible solutions as do data mining techniques in large datasets. The main objective of this study is to improve the prediction of outcomes following combined heart-lung transplantation by proposing an integrated data-mining methodology. A large and feature-rich dataset (16,604 cases with 283 variables) is used to (1) develop machine learning based predictive models and (2) extract the most important predictive factors. Then, using three different variable selection methods, namely, (i) machine learning methods driven variables-using decision trees, neural networks, logistic regression, (ii) the literature review-based expert-defined variables, and (iii) common sense-based interaction variables, a consolidated set of factors is generated and used to develop Cox regression models for heart-lung graft survival. The predictive models' performance in terms of 10-fold cross-validation accuracy rates for two multi-imputed datasets ranged from 79% to 86% for neural networks, from 78% to 86% for logistic regression, and from 71% to 79% for decision trees. The results indicate that the proposed integrated data mining methodology using Cox hazard models better predicted the graft survival with different variables than the conventional approaches commonly used in the literature. This result is validated by the comparison of the corresponding Gains charts for our proposed methodology and the literature review based Cox results, and by the comparison of Akaike information criteria (AIC) values received from each. Data mining-based methodology proposed in this study reveals that there are undiscovered relationships (i.e. interactions of the existing variables) among the survival-related variables, which helps better predict the survival of the heart-lung transplants. It also brings a different set of variables into the scene to be evaluated by the domain-experts and be considered prior to the organ transplantation.
Population dynamics of king eiders breeding in northern Alaska
Bentzen, Rebecca L.; Powell, Abby N.
2012-01-01
The North American population of king eiders (Somateria spectabilis) has declined by more than 50% since the late 1970s for unknown reasons. King eiders spend most of their lives in remote areas, forcing managers to make regulatory and conservation decisions based on very little information. We incorporated available published estimates of vital rates with new estimates to build a female, stage-based matrix population model for king eiders and examine the processes underlying population dynamics of king eiders breeding at 2 sites, Teshekpuk and Kuparuk, on the coastal plain of northern Alaska and wintering around the Bering Sea (2001–2010). We predicted a decreasing population (λ = 0.981, 95% CI: 0.978–0.985), and that population growth was most sensitive to changes in adult female survival (sensitivity = 0.92). Low duckling survival may be a bottleneck to productivity (variation in ducking survival accounted for 66% of retrospective variation in λ). Adult survival was high (0.94) and invariant (σ = 0.0002, 95% CI: 0.0000–0.0007); however, catastrophic events could have a major impact and we need to consider how to mitigate and manage threats to adult survival. A hypothetical oil spill affecting breeding females in a primary spring staging area resulted in a severe population decline; although, transient population dynamics were relatively stable. However, if no catastrophic events occur, the more variable reproductive parameters (duckling and nest survival) may be more responsive to management actions.
Costanzo, K S; Schelble, S; Jerz, K; Keenan, M
2015-06-01
Several studies have examined how climatic variables such as temperature and precipitation may affect life history traits in mosquitoes that are important to disease transmission. Despite its importance as a seasonal cue in nature, studies investigating the influence of photoperiod on such traits are relatively few. This study aims to investigate how photoperiod alters life history traits, survival, and blood-feeding activity in Aedes albopictus (Skuse) and Aedes aegypti (Linnaeus). We performed three experiments that tested the effects of day length on female survival, development time, adult size, fecundity, adult life span, and propensity to blood feed in Ae. albopictus and Ae. aegypti. Each experiment had three photoperiod treatments: 1) short-day (10L:14D), 2) control (12L:12D), and 3) long-day (14L:10D). Aedes albopictus adult females were consistently larger in size when reared in short-day conditions. Aedes aegypti adult females from short-day treatments lived longer and were more likely to take a blood meal compared to other treatments. We discuss how species-specific responses may reflect alternative strategies evolved to increase survival during unfavorable conditions. We review the potential impacts of these responses on seasonal transmission patterns, such as potentially increasing vectorial capacity of Ae. aegypti during periods of shorter day lengths. © 2015 The Society for Vector Ecology.
Tang, Z H; Geng, Z M; Chen, C; Si, S B; Cai, Z Q; Song, T Q; Gong, P; Jiang, L; Qiu, Y H; He, Y; Zhai, W L; Li, S P; Zhang, Y C; Yang, Y
2018-05-01
Objective: To investigate the clinical value of Bayesian network in predicting survival of patients with advanced gallbladder cancer(GBC)who underwent curative intent surgery. Methods: The clinical data of patients with advanced GBC who underwent curative intent surgery in 9 institutions from January 2010 to December 2015 were analyzed retrospectively.A median survival time model based on a tree augmented naïve Bayes algorithm was established by Bayesia Lab software.The survival time, number of metastatic lymph nodes(NMLN), T stage, pathological grade, margin, jaundice, liver invasion, age, sex and tumor morphology were included in this model.Confusion matrix, the receiver operating characteristic curve and area under the curve were used to evaluate the accuracy of the model.A priori statistical analysis of these 10 variables and a posterior analysis(survival time as the target variable, the remaining factors as the attribute variables)was performed.The importance rankings of each variable was calculated with the polymorphic Birnbaum importance calculation based on the posterior analysis results.The survival probability forecast table was constructed based on the top 4 prognosis factors. The survival curve was drawn by the Kaplan-Meier method, and differences in survival curves were compared using the Log-rank test. Results: A total of 316 patients were enrolled, including 109 males and 207 females.The ratio of male to female was 1.0∶1.9, the age was (62.0±10.8)years.There was 298 cases(94.3%) R0 resection and 18 cases(5.7%) R1 resection.T staging: 287 cases(90.8%) T3 and 29 cases(9.2%) T4.The median survival time(MST) was 23.77 months, and the 1, 3, 5-year survival rates were 67.4%, 40.8%, 32.0%, respectively.For the Bayesian model, the number of correctly predicted cases was 121(≤23.77 months) and 115(>23.77 months) respectively, leading to a 74.86% accuracy of this model.The prior probability of survival time was 0.503 2(≤23.77 months) and 0.496 8(>23.77 months), the importance ranking showed that NMLN(0.366 6), margin(0.350 1), T stage(0.319 2) and pathological grade(0.258 9) were the top 4 prognosis factors influencing the postoperative MST.These four factors were taken as observation variables to get the probability of patients in different survival periods.Basing on these results, a survival prediction score system including NMLN, margin, T stage and pathological grade was designed, the median survival time(month) of 4-9 points were 66.8, 42.4, 26.0, 9.0, 7.5 and 2.3, respectively, there was a statistically significant difference in the different points( P <0.01). Conclusions: The survival prediction model of GBC based on Bayesian network has high accuracy.NMLN, margin, T staging and pathological grade are the top 4 risk factors affecting the survival of patients with advanced GBC who underwent curative resection.The survival prediction score system based on these four factors could be used to predict the survival and to guide the decision making of patients with advanced GBC.
The effect of the AED and AED programs on survival of individuals, groups and populations.
Stokes, Nathan Allen; Scapigliati, Andrea; Trammell, Antoine R; Parish, David C
2012-10-01
The automated external defibrillator (AED) is a tool that contributes to survival with mixed outcomes. This review assesses the effectiveness of the AED, consistencies and variations among studies, and how varying outcomes can be resolved. A worksheet for the International Liaison Committee on Resuscitation (ILCOR) 2010 science review focused on hospital survival in AED programs was the foundation of the articles reviewed. Articles identified in the search covering a broader range of topics were added. All articles were read by at least two authors; consensus discussions resolved differences. AED use developed sequentially. Use of AEDs by emergency medical technicians (EMTs) compared to manual defibrillators showed equal or superior survival. AED use was extended to trained responders likely to be near victims, such as fire/rescue, police, airline attendants, and casino security guards, with improvement in all venues but not all programs. Broad public access initiatives demonstrated increased survival despite low rates of AED use. Home AED programs have not improved survival; in-hospital trials have had mixed results. Successful programs have placed devices in high-risk sites, maintained the AEDs, recruited a team with a duty to respond, and conducted ongoing assessment of the program. The AED can affect survival among patients with sudden ventricular fibrillation (VF). Components of AED programs that affect outcome include the operator, location, the emergency response system, ongoing maintenance and evaluation. Comparing outcomes is complicated by variations in definitions of populations and variables. The effect of AEDs on individuals can be dramatic, but the effect on populations is limited.
Valsangkar, Nakul P; Bush, Devon M; Michaelson, James S; Ferrone, Cristina R; Wargo, Jennifer A; Lillemoe, Keith D; Fernández-del Castillo, Carlos; Warshaw, Andrew L; Thayer, Sarah P
2013-02-01
We evaluated the prognostic accuracy of LN variables (N0/N1), numbers of positive lymph nodes (PLN), and lymph node ratio (LNR) in the context of the total number of examined lymph nodes (ELN). Patients from SEER and a single institution (MGH) were reviewed and survival analyses performed in subgroups based on numbers of ELN to calculate excess risk of death (hazard ratio, HR). In SEER and MGH, higher numbers of ELN improved the overall survival for N0 patients. The prognostic significance (N0/N1) and PLN were too variable as the importance of a single PLN depended on the total number of LN dissected. LNR consistently correlated with survival once a certain number of lymph nodes were dissected (≥13 in SEER and ≥17 in the MGH dataset). Better survival for N0 patients with increasing ELN likely represents improved staging. PLN have some predictive value but the ELN strongly influence their impact on survival, suggesting the need for a ratio-based classification. LNR strongly correlates with outcome provided that a certain number of lymph nodes is evaluated, suggesting that the prognostic accuracy of any LN variable depends on the total number of ELN.
Macalady, Alison K.; Bugmann, Harald
2014-01-01
The processes leading to drought-associated tree mortality are poorly understood, particularly long-term predisposing factors, memory effects, and variability in mortality processes and thresholds in space and time. We use tree rings from four sites to investigate Pinus edulis mortality during two drought periods in the southwestern USA. We draw on recent sampling and archived collections to (1) analyze P. edulis growth patterns and mortality during the 1950s and 2000s droughts; (2) determine the influence of climate and competition on growth in trees that died and survived; and (3) derive regression models of growth-mortality risk and evaluate their performance across space and time. Recent growth was 53% higher in surviving vs. dying trees, with some sites exhibiting decades-long growth divergences associated with previous drought. Differential growth response to climate partly explained growth differences between live and dead trees, with responses wet/cool conditions most influencing eventual tree status. Competition constrained tree growth, and reduced trees’ ability to respond to favorable climate. The best predictors in growth-mortality models included long-term (15–30 year) average growth rate combined with a metric of growth variability and the number of abrupt growth increases over 15 and 10 years, respectively. The most parsimonious models had high discriminatory power (ROC>0.84) and correctly classified ∼70% of trees, suggesting that aspects of tree growth, especially over decades, can be powerful predictors of widespread drought-associated die-off. However, model discrimination varied across sites and drought events. Weaker growth-mortality relationships and higher growth at lower survival probabilities for some sites during the 2000s event suggest a shift in mortality processes from longer-term growth-related constraints to shorter-term processes, such as rapid metabolic decline even in vigorous trees due to acute drought stress, and/or increases in the attack rate of both chronically stressed and more vigorous trees by bark beetles. PMID:24786646
Macalady, Alison K; Bugmann, Harald
2014-01-01
The processes leading to drought-associated tree mortality are poorly understood, particularly long-term predisposing factors, memory effects, and variability in mortality processes and thresholds in space and time. We use tree rings from four sites to investigate Pinus edulis mortality during two drought periods in the southwestern USA. We draw on recent sampling and archived collections to (1) analyze P. edulis growth patterns and mortality during the 1950s and 2000s droughts; (2) determine the influence of climate and competition on growth in trees that died and survived; and (3) derive regression models of growth-mortality risk and evaluate their performance across space and time. Recent growth was 53% higher in surviving vs. dying trees, with some sites exhibiting decades-long growth divergences associated with previous drought. Differential growth response to climate partly explained growth differences between live and dead trees, with responses wet/cool conditions most influencing eventual tree status. Competition constrained tree growth, and reduced trees' ability to respond to favorable climate. The best predictors in growth-mortality models included long-term (15-30 year) average growth rate combined with a metric of growth variability and the number of abrupt growth increases over 15 and 10 years, respectively. The most parsimonious models had high discriminatory power (ROC>0.84) and correctly classified ∼ 70% of trees, suggesting that aspects of tree growth, especially over decades, can be powerful predictors of widespread drought-associated die-off. However, model discrimination varied across sites and drought events. Weaker growth-mortality relationships and higher growth at lower survival probabilities for some sites during the 2000s event suggest a shift in mortality processes from longer-term growth-related constraints to shorter-term processes, such as rapid metabolic decline even in vigorous trees due to acute drought stress, and/or increases in the attack rate of both chronically stressed and more vigorous trees by bark beetles.
Rajan, Shahzleen; Wissenberg, Mads; Folke, Fredrik; Hansen, Steen Møller; Gerds, Thomas A; Kragholm, Kristian; Hansen, Carolina Malta; Karlsson, Lena; Lippert, Freddy K; Køber, Lars; Gislason, Gunnar H; Torp-Pedersen, Christian
2016-12-20
Bystander-initiated cardiopulmonary resuscitation (CPR) increases patient survival after out-of-hospital cardiac arrest, but it is unknown to what degree bystander CPR remains positively associated with survival with increasing time to potential defibrillation. The main objective was to examine the association of bystander CPR with survival as time to advanced treatment increases. We studied 7623 out-of-hospital cardiac arrest patients between 2005 and 2011, identified through the nationwide Danish Cardiac Arrest Registry. Multiple logistic regression analysis was used to examine the association between time from 911 call to emergency medical service arrival (response time) and survival according to whether bystander CPR was provided (yes or no). Reported are 30-day survival chances with 95% bootstrap confidence intervals. With increasing response times, adjusted 30-day survival chances decreased for both patients with bystander CPR and those without. However, the contrast between the survival chances of patients with versus without bystander CPR increased over time: within 5 minutes, 30-day survival was 14.5% (95% confidence interval [CI]: 12.8-16.4) versus 6.3% (95% CI: 5.1-7.6), corresponding to 2.3 times higher chances of survival associated with bystander CPR; within 10 minutes, 30-day survival chances were 6.7% (95% CI: 5.4-8.1) versus 2.2% (95% CI: 1.5-3.1), corresponding to 3.0 times higher chances of 30-day survival associated with bystander CPR. The contrast in 30-day survival became statistically insignificant when response time was >13 minutes (bystander CPR vs no bystander CPR: 3.7% [95% CI: 2.2-5.4] vs 1.5% [95% CI: 0.6-2.7]), but 30-day survival was still 2.5 times higher associated with bystander CPR. Based on the model and Danish out-of-hospital cardiac arrest statistics, an additional 233 patients could potentially be saved annually if response time was reduced from 10 to 5 minutes and 119 patients if response time was reduced from 7 (the median response time in this study) to 5 minutes. The absolute survival associated with bystander CPR declined rapidly with time. Yet bystander CPR while waiting for an ambulance was associated with a more than doubling of 30-day survival even in case of long ambulance response time. Decreasing ambulance response time by even a few minutes could potentially lead to many additional lives saved every year. © 2016 American Heart Association, Inc.
Spectral analysis of heart rate variability predicts mortality and instability from vascular injury.
Koko, Kiavash R; McCauley, Brian D; Gaughan, John P; Fromer, Marc W; Nolan, Ryan S; Hagaman, Ashleigh L; Brown, Spencer A; Hazelton, Joshua P
2018-04-01
Spectral analysis of continuous blood pressure and heart rate variability provides a quantitative assessment of autonomic response to hemorrhage. This may reveal markers of mortality as well as endpoints of resuscitation. Fourteen male Yorkshire pigs, ranging in weight from 33 to 36 kg, were included in the analysis. All pigs underwent laparotomy and then sustained a standardized retrohepatic inferior vena cava injury. Animals were then allowed to progress to class 3 hemorrhagic shock and where then treated with abdominal sponge packing followed by 6 h of crystalloid resuscitation. If the pigs survived the 6 h resuscitation, they were in the survival (S) group, otherwise they were placed in the nonsurvival (NS) group. Fast Fourier transformation calculations were used to convert the components of blood pressure and heart rate variability into corresponding frequency classifications. Autonomic tones are represented as the following: high frequency (HF) = parasympathetic tone, low frequency (LF) = sympathetic, and very low frequency (VLF) = renin-angiotensin aldosterone system. The relative sympathetic to parasympathetic tone was expressed as LF/HF ratio. Baseline hemodynamic parameters were equal for the S (n = 11) and NS groups. LF/HF was lower at baseline for the NS group but was higher after hemorrhage and the resuscitation period indicative of a predominately parasympathetic response during hemorrhagic shock before mortality. HF signal was lower in the NS group during the resuscitation indicating a relatively lower sympathetic tone during hemorrhagic shock, which may have contributed to mortality. Finally, the NS group had a lower VLF signal at baseline (e.g., [S] 16.3 ± 2.5 versus [NS] 4.6 ± 2.9 P < 0.05,) which was predictive of mortality and hemodynamic instability in response to a similar hemorrhagic injury. An increased LF/HF ratio, indicative of parasympathetic predominance following injury and during resuscitation of hemorrhagic shock was a marker of impending death. Spectral analysis of heart rate variability can also identify autonomic lability following hemorrhagic injuries with implications for first responder triage. Furthermore, a decreased VLF signal at baseline indicates an additional marker of hemodynamic instability and marker of mortality following a hemorrhagic injury. These data indicate that continuous quantitative assessment of autonomic response can be a predictor of mortality and potentially guide resuscitation of patients in hemorrhagic shock. Copyright © 2017 Elsevier Inc. All rights reserved.
Smith, Brian H.; Burden, Christina M.
2014-01-01
Insects modify their responses to stimuli through experience of associating those stimuli with events important for survival (e.g., food, mates, threats). There are several behavioral mechanisms through which an insect learns salient associations and relates them to these events. It is important to understand this behavioral plasticity for programs aimed toward assisting insects that are beneficial for agriculture. This understanding can also be used for discovering solutions to biomedical and agricultural problems created by insects that act as disease vectors and pests. The Proboscis Extension Response (PER) conditioning protocol was developed for honey bees (Apis mellifera) over 50 years ago to study how they perceive and learn about floral odors, which signal the nectar and pollen resources a colony needs for survival. The PER procedure provides a robust and easy-to-employ framework for studying several different ecologically relevant mechanisms of behavioral plasticity. It is easily adaptable for use with several other insect species and other behavioral reflexes. These protocols can be readily employed in conjunction with various means for monitoring neural activity in the CNS via electrophysiology or bioimaging, or for manipulating targeted neuromodulatory pathways. It is a robust assay for rapidly detecting sub-lethal effects on behavior caused by environmental stressors, toxins or pesticides. We show how the PER protocol is straightforward to implement using two procedures. One is suitable as a laboratory exercise for students or for quick assays of the effect of an experimental treatment. The other provides more thorough control of variables, which is important for studies of behavioral conditioning. We show how several measures for the behavioral response ranging from binary yes/no to more continuous variable like latency and duration of proboscis extension can be used to test hypotheses. And, we discuss some pitfalls that researchers commonly encounter when they use the procedure for the first time. PMID:25225822
Delay of Treatment Initiation Does Not Adversely Affect Survival Outcome in Breast Cancer.
Yoo, Tae-Kyung; Han, Wonshik; Moon, Hyeong-Gon; Kim, Jisun; Lee, Jun Woo; Kim, Min Kyoon; Lee, Eunshin; Kim, Jongjin; Noh, Dong-Young
2016-07-01
Previous studies examining the relationship between time to treatment and survival outcome in breast cancer have shown inconsistent results. The aim of this study was to analyze the overall impact of delay of treatment initiation on patient survival and to determine whether certain subgroups require more prompt initiation of treatment. This study is a retrospective analysis of stage I-III patients who were treated in a single tertiary institution between 2005 and 2008. Kaplan-Meier survival analysis and Cox proportional hazards regression model were used to evaluate the impact of interval between diagnosis and treatment initiation in breast cancer and various subgroups. A total of 1,702 patients were included. Factors associated with longer delay of treatment initiation were diagnosis at another hospital, medical comorbidities, and procedures performed before admission for surgery. An interval between diagnosis and treatment initiation as a continuous variable or with a cutoff value of 15, 30, 45, and 60 days had no impact on disease-free survival (DFS). Subgroup analyses for hormone-responsiveness, triple-negative breast cancer, young age, clinical stage, and type of initial treatment showed no significant association between longer delay of treatment initiation and DFS. Our results show that an interval between diagnosis and treatment initiation of 60 days or shorter does not appear to adversely affect DFS in breast cancer.
Using physiology to predict the responses of ants to climatic warming.
Diamond, Sarah E; Penick, Clint A; Pelini, Shannon L; Ellison, Aaron M; Gotelli, Nicholas J; Sanders, Nathan J; Dunn, Robert R
2013-12-01
Physiological intolerance of high temperatures places limits on organismal responses to the temperature increases associated with global climatic change. Because ants are geographically widespread, ecologically diverse, and thermophilic, they are an ideal system for exploring the extent to which physiological tolerance can predict responses to environmental change. Here, we expand on simple models that use thermal tolerance to predict the responses of ants to climatic warming. We investigated the degree to which changes in the abundance of ants under warming reflect reductions in the thermal niche space for their foraging. In an eastern deciduous forest system in the United States with approximately 40 ant species, we found that for some species, the loss of thermal niche space for foraging was related to decreases in abundance with increasing experimental climatic warming. However, many ant species exhibited no loss of thermal niche space. For one well-studied species, Temnothorax curvispinosus, we examined both survival of workers and growth of colonies (a correlate of reproductive output) as functions of temperature in the laboratory, and found that the range of thermal tolerances for colony growth was much narrower than for survival of workers. We evaluated these functions in the context of experimental climatic warming and found that the difference in the responses of these two attributes to temperature generates differences in the means and especially the variances of expected fitness under warming. The expected mean growth of colonies was optimized at intermediate levels of warming (2-4°C above ambient); yet, the expected variance monotonically increased with warming. In contrast, the expected mean and variance of the survival of workers decreased when warming exceeded 4°C above ambient. Together, these results for T. curvispinosus emphasize the importance of measuring reproduction (colony growth) in the context of climatic change: indeed, our examination of the loss of thermal niche space with the larger species pool could be missing much of the warming impact due to these analyses being based on survival rather than reproduction. We suggest that while physiological tolerance of temperature can be a useful predictive tool for modeling responses to climatic change, future efforts should be devoted to understanding the causes and consequences of variability in models of tolerance calibrated with different metrics of performance and fitness.
Climate variability slows evolutionary responses of Colias butterflies to recent climate change.
Kingsolver, Joel G; Buckley, Lauren B
2015-03-07
How does recent climate warming and climate variability alter fitness, phenotypic selection and evolution in natural populations? We combine biophysical, demographic and evolutionary models with recent climate data to address this question for the subalpine and alpine butterfly, Colias meadii, in the southern Rocky Mountains. We focus on predicting patterns of selection and evolution for a key thermoregulatory trait, melanin (solar absorptivity) on the posterior ventral hindwings, which affects patterns of body temperature, flight activity, adult and egg survival, and reproductive success in Colias. Both mean annual summer temperatures and thermal variability within summers have increased during the past 60 years at subalpine and alpine sites. At the subalpine site, predicted directional selection on wing absorptivity has shifted from generally positive (favouring increased wing melanin) to generally negative during the past 60 years, but there is substantial variation among years in the predicted magnitude and direction of selection and the optimal absorptivity. The predicted magnitude of directional selection at the alpine site declined during the past 60 years and varies substantially among years, but selection has generally been positive at this site. Predicted evolutionary responses to mean climate warming at the subalpine site since 1980 is small, because of the variability in selection and asymmetry of the fitness function. At both sites, the predicted effects of adaptive evolution on mean population fitness are much smaller than the fluctuations in mean fitness due to climate variability among years. Our analyses suggest that variation in climate within and among years may strongly limit evolutionary responses of ectotherms to mean climate warming in these habitats. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
Survival and predictors of death among primary immunodeficient patients: a registry-based study.
Al-Herz, Waleed; Moussa, Mohamed A A
2012-06-01
The aims of this study were to investigate survival among patients with primary immunodeficiency disorders (PID) in Kuwait and to determine whether certain variables were associated with increased risk of death. The data of 176 patients (98 males and 78 females) were extracted from the Kuwait National Primary Immunodeficiency Disorders Registry and the observation period was from January 2004 to July 2011. The distribution of the reported patients was combined T- and B-cell immunodeficiencies (30.1%), predominantly antibody immunodeficiency (19.9%), other well-defined immunodeficiencies (25%), diseases of immune dysregulation (14.8%), congenital defects of phagocyte number, function or both (6.25%), and complement deficiencies (4.0%). In a total of 619.1 patient-years at risk, 48 patients died (mortality incidence rate 77.53 per 1,000 person-years). The overall survival in the studied cohort was 72.7% (72.4% for males and 73.1% for females). The most common cause of death was sepsis (46%) followed by pneumonia (29%). The probabilities that a patient survived 2, 4, and 6 years after onset of symptoms were 76%, 73%, and 69%, respectively. The variables that were found to be predictors for death are parental consanguinity, sepsis, adenovirus and CMV infections, failure to thrive, PID category, and onset age <6 months. Patients with PID have decreased probabilities of survival that are variable between PID categories. Early diagnosis and aggressive therapeutic interventions specifically of patients with history of the variables associated with increased risk of death may help increase their chance of survival.
Zheng, Wenjing; van der Laan, Mark
2017-01-01
In this paper, we study the effect of a time-varying exposure mediated by a time-varying intermediate variable. We consider general longitudinal settings, including survival outcomes. At a given time point, the exposure and mediator of interest are influenced by past covariates, mediators and exposures, and affect future covariates, mediators and exposures. Right censoring, if present, occurs in response to past history. To address the challenges in mediation analysis that are unique to these settings, we propose a formulation in terms of random interventions based on conditional distributions for the mediator. This formulation, in particular, allows for well-defined natural direct and indirect effects in the survival setting, and natural decomposition of the standard total effect. Upon establishing identifiability and the corresponding statistical estimands, we derive the efficient influence curves and establish their robustness properties. Applying Targeted Maximum Likelihood Estimation, we use these efficient influence curves to construct multiply robust and efficient estimators. We also present an inverse probability weighted estimator and a nested non-targeted substitution estimator for these parameters. PMID:29387520
Asano, Junichi; Hirakawa, Akihiro; Hamada, Chikuma; Yonemori, Kan; Hirata, Taizo; Shimizu, Chikako; Tamura, Kenji; Fujiwara, Yasuhiro
2013-01-01
In prognostic studies for breast cancer patients treated with neoadjuvant chemotherapy (NAC), the ordinary Cox proportional-hazards (PH) model has been often used to identify prognostic factors for disease-free survival (DFS). This model assumes that all patients eventually experience relapse or death. However, a subset of NAC-treated breast cancer patients never experience these events during long-term follow-up (>10 years) and may be considered clinically "cured." Clinical factors associated with cure have not been studied adequately. Because the ordinary Cox PH model cannot be used to identify such clinical factors, we used the Cox PH cure model, a recently developed statistical method. This model includes both a logistic regression component for the cure rate and a Cox regression component for the hazard for uncured patients. The purpose of this study was to identify the clinical factors associated with cure and the variables associated with the time to recurrence or death in NAC-treated breast cancer patients without a pathologic complete response, by using the Cox PH cure model. We found that hormone receptor status, clinical response, human epidermal growth factor receptor 2 status, histological grade, and the number of lymph node metastases were associated with cure.
Alternative Glycerol Balance Strategies among Saccharomyces Species in Response to Winemaking Stress
Pérez-Torrado, Roberto; Oliveira, Bruno M.; Zemančíková, Jana; Sychrová, Hana; Querol, Amparo
2016-01-01
Production and balance of glycerol is essential for the survival of yeast cells in certain stressful conditions as hyperosmotic or cold shock that occur during industrial processes as winemaking. These stress responses are well-known in S. cerevisiae, however, little is known in other phylogenetically close related Saccharomyces species associated with natural or fermentation environments such as S. uvarum, S. paradoxus or S. kudriavzevii. In this work we have investigated the expression of four genes (GPD1, GPD2, STL1, and FPS1) crucial in the glycerol pool balance in the four species with a biotechnological potential (S. cerevisiae; S. paradoxus; S. uvarum; and S. kudriavzevii), and the ability of strains to grow under osmotic and cold stresses. The results show different pattern and level of expression among the different species, especially for STL1. We also studied the function of Stl1 glycerol symporter in the survival to osmotic changes and cell growth capacity in winemaking environments. These experiments also revealed a different functionality of the glycerol transporters among the different species studied. All these data point to different strategies to handle glycerol accumulation in response to winemaking stresses as hyperosmotic or cold-hyperosmotic stress in the different species, with variable emphasis in the production, influx, or efflux of glycerol. PMID:27064588
Swords, Ronan T; Azzam, Diana; Al-Ali, Hassan; Lohse, Ines; Volmar, Claude-Henry; Watts, Justin M; Perez, Aymee; Rodriguez, Ana; Vargas, Fernando; Elias, Roy; Vega, Francisco; Zelent, Arthur; Brothers, Shaun P; Abbasi, Taher; Trent, Jonathan; Rangwala, Shaukat; Deutsch, Yehuda; Conneally, Eibhlin; Drusbosky, Leylah; Cogle, Christopher R; Wahlestedt, Claes
2018-01-01
A precision medicine approach is appealing for use in AML due to ease of access to tumor samples and the significant variability in the patients' response to treatment. Attempts to establish a precision medicine platform for AML, however, have been unsuccessful, at least in part due to the use of small compound panels and having relatively slow turn over rates, which restricts the scope of treatment and delays its onset. For this pilot study, we evaluated a cohort of 12 patients with refractory AML using an ex vivo drug sensitivity testing (DST) platform. Purified AML blasts were screened with a panel of 215 FDA-approved compounds and treatment response was evaluated after 72h of exposure. Drug sensitivity scoring was reported to the treating physician, and patients were then treated with either DST- or non-DST guided therapy. We observed survival benefit of DST-guided therapy as compared to the survival of patients treated according to physician recommendation. Three out of four DST-treated patients displayed treatment response, while all of the non-DST-guided patients progressed during treatment. DST rapidly and effectively provides personalized treatment recommendations for patients with refractory AML. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
A nomogram to predict the survival of stage IIIA-N2 non-small cell lung cancer after surgery.
Mao, Qixing; Xia, Wenjie; Dong, Gaochao; Chen, Shuqi; Wang, Anpeng; Jin, Guangfu; Jiang, Feng; Xu, Lin
2018-04-01
Postoperative survival of patients with stage IIIA-N2 non-small cell lung cancer (NSCLC) is highly heterogeneous. Here, we aimed to identify variables associated with postoperative survival and develop a tool for survival prediction. A retrospective review was performed in the Surveillance, Epidemiology, and End Results database from January 2004 to December 2009. Significant variables were selected by use of the backward stepwise method. The nomogram was constructed with multivariable Cox regression. The model's performance was evaluated by concordance index and calibration curve. The model was validated via an independent cohort from the Jiangsu Cancer Hospital Lung Cancer Center. A total of 1809 patients with stage IIIA-N2 NSCLC who underwent surgery were included in the training cohort. Age, sex, grade, histology, tumor size, visceral pleural invasion, positive lymph nodes, lymph nodes examined, and surgery type (lobectomy vs pneumonectomy) were identified as significant prognostic variables using backward stepwise method. A nomogram was developed from the training cohort and validated using an independent Chinese cohort. The concordance index of the model was 0.673 (95% confidence interval, 0.654-0.692) in training cohort and 0.664 in validation cohort (95% confidence interval, 0.614-0.714). The calibration plot showed optimal consistency between nomogram predicted survival and observed survival. Survival analyses demonstrated significant differences between different subgroups stratified by prognostic scores. This nomogram provided the individual survival prediction for patients with stage IIIA-N2 NSCLC after surgery, which might benefit survival counseling for patients and clinicians, clinical trial design and follow-up, as well as postoperative strategy-making. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.
Kruse, M A; Holmes, E S; Balko, J A; Fernandez, S; Brown, D C; Goldschmidt, M H
2013-07-01
Osteosarcoma is the most common bone tumor in dogs. However, current literature focuses primarily on appendicular osteosarcoma. This study examined the prognostic value of histological and clinical factors in flat and irregular bone osteosarcomas and hypothesized that clinical factors would have a significant association with survival time while histological factors would not. All osteosarcoma biopsy samples of the vertebra, rib, sternum, scapula, or pelvis were reviewed while survival information and clinical data were obtained from medical records, veterinarians, and owners. Forty-six dogs were included in the analysis of histopathological variables and 27 dogs with complete clinical data were included in the analysis of clinical variables. In the histopathologic cox regression model, there was no significant association between any histologic feature of osteosarcoma, including grade, and survival time. In the clinical cox regression model, there was a significant association between the location of the tumor and survival time as well as between the percent elevation of alkaline phosphatase (ALP) above normal and survival time. Controlling for ALP elevation, dogs with osteosarcoma located in the scapula had a significantly greater hazard for death (2.8) compared to dogs with tumors in other locations. Controlling for tumor location, every 100% increase in ALP from normal increased the hazard for death by 1.7. For canine osteosarcomas of the flat and irregular bones, histopathological features, including grade do not appear to be rigorous predictors of survival. Clinical variables such as increased ALP levels and tumor location in the scapula were associated with decreased survival times.
Smyth, Elizabeth C.; Fassan, Matteo; Cunningham, David; Allum, William H.; Okines, Alicia F.C.; Lampis, Andrea; Hahne, Jens C.; Rugge, Massimo; Peckitt, Clare; Nankivell, Matthew; Langley, Ruth; Ghidini, Michele; Braconi, Chiara; Wotherspoon, Andrew; Grabsch, Heike I.
2016-01-01
Purpose The Medical Research Council Adjuvant Gastric Infusional Chemotherapy (MAGIC) trial established perioperative epirubicin, cisplatin, and fluorouracil chemotherapy as a standard of care for patients with resectable esophagogastric cancer. However, identification of patients at risk for relapse remains challenging. We evaluated whether pathologic response and lymph node status after neoadjuvant chemotherapy are prognostic in patients treated in the MAGIC trial. Materials and Methods Pathologic regression was assessed in resection specimens by two independent pathologists using the Mandard tumor regression grading system (TRG). Differences in overall survival (OS) according to TRG were assessed using the Kaplan-Meier method and compared using the log-rank test. Univariate and multivariate analyses using the Cox proportional hazards method established the relationships among TRG, clinical-pathologic variables, and OS. Results Three hundred thirty resection specimens were analyzed. In chemotherapy-treated patients with a TRG of 1 or 2, median OS was not reached, whereas for patients with a TRG of 3, 4, or 5, median OS was 20.47 months. On univariate analysis, high TRG and lymph node metastases were negatively related to survival (Mandard TRG 3, 4, or 5: hazard ratio [HR], 1.94; 95% CI, 1.11 to 3.39; P = .0209; lymph node metastases: HR, 3.63; 95% CI, 1.88 to 7.0; P < .001). On multivariate analysis, only lymph node status was independently predictive of OS (HR, 3.36; 95% CI, 1.70 to 6.63; P < .001). Conclusion Lymph node metastases and not pathologic response to chemotherapy was the only independent predictor of survival after chemotherapy plus resection in the MAGIC trial. Prospective evaluation of whether omitting postoperative chemotherapy and/or switching to a noncross-resistant regimen in patients with lymph node-positive disease whose tumor did not respond to preoperative epirubicin, cisplatin, and fluorouracil may be appropriate. PMID:27298411
Gama-Flores, José Luis; Huidobro-Salas, María Elena; Sarma, S S S; Nandini, S
2017-01-01
In this study, we quantified intergenerational, demographic variability of Moina macrocopa subjected to cadmium stress. Exposure of M macrocopa to cadmium (0.2, 0.3, and 0.4 mg/L as CdCl 2 ) through 4 consecutive generations revealed changes in demographic responses not only in survivorship variables but also in reproductive parameters. Long-term demographic responses varied differently, depending on the demographic trait and the concentration of heavy metal in the medium. With the exception of generation time, all life history traits were significantly and adversely influenced due to increase in Cd concentrations. The average life span of M macrocopa varied up to 40% depending on Cd level and the generation of exposure. The highest gross reproductive rates were recorded in controls, while the lowest (∼30% less) were recorded at the highest Cd level. Survival-weighted net reproductive rates were reduced by nearly 50% due to Cd toxicity. The rate of population increase per day of M macrocopa was also significantly affected (∼25%) by Cd as compared to controls. This cladoceran showed a dose-response to Cd toxicity with a significance in both magnitude and frequency of offspring production.
Gama-Flores, José Luis; Huidobro-Salas, María Elena; Sarma, S.S.S.; Nandini, S.
2017-01-01
In this study, we quantified intergenerational, demographic variability of Moina macrocopa subjected to cadmium stress. Exposure of M macrocopa to cadmium (0.2, 0.3, and 0.4 mg/L as CdCl2) through 4 consecutive generations revealed changes in demographic responses not only in survivorship variables but also in reproductive parameters. Long-term demographic responses varied differently, depending on the demographic trait and the concentration of heavy metal in the medium. With the exception of generation time, all life history traits were significantly and adversely influenced due to increase in Cd concentrations. The average life span of M macrocopa varied up to 40% depending on Cd level and the generation of exposure. The highest gross reproductive rates were recorded in controls, while the lowest (∼30% less) were recorded at the highest Cd level. Survival-weighted net reproductive rates were reduced by nearly 50% due to Cd toxicity. The rate of population increase per day of M macrocopa was also significantly affected (∼25%) by Cd as compared to controls. This cladoceran showed a dose–response to Cd toxicity with a significance in both magnitude and frequency of offspring production. PMID:28835748
NASA Astrophysics Data System (ADS)
Bi, R.; Liu, H.
2016-02-01
Understanding how biological components respond to environmental changes could be insightful to predict ecosystem trajectories under different climate scenarios. Zooplankton are key components of marine ecosystems and changes in their dynamics could have major impact on ecosystem structure. We developed an individual-based model of a common coastal calanoid copepod Acartia tonsa to examine how environmental factors affect zooplankton population dynamics and explore the role of individual variability in sustaining population under various environmental conditions consisting of temperature, food concentration and salinity. Total abundance, egg production and proportion of survival were used to measure population success. Results suggested population benefits from high level of individual variability under extreme environmental conditions including unfavorable temperature, salinity, as well as low food concentration, and selection on fast-growers becomes stronger with increasing individual variability and increasing environmental stress. Multiple regression analysis showed that temperature, food concentration, salinity and individual variability have significant effects on survival of A. tonsa population. These results suggest that environmental factors have great influence on zooplankton population, and individual variability has important implications for population survivability under unfavorable conditions. Given that marine ecosystems are at risk from drastic environmental changes, understanding how individual variability sustains populations could increase our capability to predict population dynamics in a changing environment.
Zidan, Jamal; Karen, Drumea; Stein, Moshe; Rosenblatt, Edward; Basher, Walid; Kuten, Abraham
2003-03-01
The follicular variant of papillary thyroid carcinoma (FVPTC) is a common subtype of papillary thyroid carcinoma. Few studies have compared the clinical behavior and treatment outcome of patients with FVPTC with the outcome of patients with pure papillary carcinoma (PTC). A retrospective study was performed to identify the influence of FVPTC compared with PTC on therapeutic variables, prognostic variables, and survival. A clinicopathologic analysis of 243 patients with papillary carcinoma was performed. One hundred forty-three tumors were PTC, and 100 tumors were FVPTC. The following variables were evaluated: age at diagnosis, tumor size, stage of tumor, treatment, capsular invasion, and survival. The median follow-up was 11.5 years. The median age was 43 years in the PTC group and 44 years in the FVPTC group. The median tumor size, disease stage, and type of initial surgery and iodine 131 ablation were similar. More patients had capsular invasion by the tumor and less metastases to cervical lymph nodes in the FVPTC group. The actuarial survival of patients age < 40 years was higher compared with the survival of patients age > 50 years in both groups. The 21-year overall actuarial survival was 82% in patients with PTC and 86% in patients with FVPTC (P value not significant). The pathologic and clinical behaviors of PTC and FVPTC were comparable. Prognostic factors, treatment, and survival also were similar. Patients in both groups must be treated identically. Copyright 2003 American Cancer Society.
Improved Endpoints for Cancer Immunotherapy Trials
Eggermont, Alexander M. M.; Janetzki, Sylvia; Hodi, F. Stephen; Ibrahim, Ramy; Anderson, Aparna; Humphrey, Rachel; Blumenstein, Brent; Wolchok, Jedd
2010-01-01
Unlike chemotherapy, which acts directly on the tumor, cancer immunotherapies exert their effects on the immune system and demonstrate new kinetics that involve building a cellular immune response, followed by changes in tumor burden or patient survival. Thus, adequate design and evaluation of some immunotherapy clinical trials require a new development paradigm that includes reconsideration of established endpoints. Between 2004 and 2009, several initiatives facilitated by the Cancer Immunotherapy Consortium of the Cancer Research Institute and partner organizations systematically evaluated an immunotherapy-focused clinical development paradigm and created the principles for redefining trial endpoints. On this basis, a body of clinical and laboratory data was generated that supports three novel endpoint recommendations. First, cellular immune response assays generate highly variable results. Assay harmonization in multicenter trials may minimize variability and help to establish cellular immune response as a reproducible biomarker, thus allowing investigation of its relationship with clinical outcomes. Second, immunotherapy may induce novel patterns of antitumor response not captured by Response Evaluation Criteria in Solid Tumors or World Health Organization criteria. New immune-related response criteria were defined to more comprehensively capture all response patterns. Third, delayed separation of Kaplan–Meier curves in randomized immunotherapy trials can affect results. Altered statistical models describing hazard ratios as a function of time and recognizing differences before and after separation of curves may allow improved planning of phase III trials. These recommendations may improve our tools for cancer immunotherapy trials and may offer a more realistic and useful model for clinical investigation. PMID:20826737
Sequential resection of lung metastasis following partial hepatectomy for colorectal cancer.
Ike, H; Shimada, H; Togo, S; Yamaguchi, S; Ichikawa, Y; Tanaka, K
2002-09-01
Multiple organ metastases from colorectal carcinoma may be considered incurable, but long survival after both liver and lung resection for metastases has been reported. A retrospective analysis of 48 patients who underwent lung resection for metastatic colorectal cancer between 1992 and 1999 was undertaken. Twenty-seven patients had lung metastasis alone, 15 had previous partial hepatectomy, and six had previous resection of local or lymph node recurrence. The relationship of clinical variables to survival was assessed. Survival was calculated from the time of first pulmonary resection. Five-year survival rates after resection of lung metastasis were 73 per cent in patients without preceding recurrence, 50 per cent following previous partial hepatectomy and zero after resection of previous local recurrence. Independent prognostic variables that significantly affected survival after thoracotomy were primary tumour histology and type of preceding recurrence. There was no significant difference in survival after lung resection between patients who had sequential liver and lung resection versus those who had lung resection alone. Sequential lung resection after partial hepatectomy for metastatic colorectal cancer may lead to long-term survival.
Ma, M A; Laguna-Teniente, I R
2016-03-01
To improve survival after kidney transplantation, it is important to identify the variables that affect it. The aim of this work was to determine the survival of renal grafts from living and cadaveric donors and the survival of patients with graft failure in a tertiary medical unit in northwest Mexico. We performed a retrospective cohort study of patients who received transplants since 2004 at the center. Database and medical records of patients were reviewed. The data were captured in a database previously designed in the SPSS v21.1 program for statistical processing. A descriptive analysis with frequencies and percentages and numeric variables measure of central tendency and dispersion was conducted. The survival analysis was made with the Kaplan-Meier method to estimate the graft survive. A total of 412 transplantations were performed during the 2004-2013 period. We analyzed 331 records, and the 10-year survival rates of donor allografts from living and cadaveric donors were 86.64% and 72.78%, respectively. Copyright © 2016 Elsevier Inc. All rights reserved.
Zhong, Dong Ta; Shi, Chun Mei; Chen, Qiang; Huang, Jing Ze; Liang, Jian Gang
2012-11-01
Non-Hodgkin's lymphoma (NHL) remains the second most common malignant complication in patients with human immunodeficiency virus (HIV) infection. Even though NHL is commonly chemosensitive to primary treatment, failure or relapse still occurs in a large number of patients. We conducted this retrospective study to evaluate the efficacy and safety of gemcitabine, dexamethasone, and cisplatin (GDP) for relapsed or refractory AIDS-related NHL (AIDS-NHL). Forty-eight patients with relapsed or refractory AIDS-NHL were treated with intravenous combination chemotherapy with GDP. The overall objective response rate was 54.1% (95% confidence interval, CI, 40.1-68.3%), with 10 complete responses and 16 partial responses. The 2-year overall survival rate (OS) was 70.8% (95% CI 58.0-83.7%), and the 5-year OS was 41.7% (95% CI 27.7-55.6%). The 2-year progression-free survival rate (PFS) was 37.5% (95% CI 23.8-51.2%), and the 5-year PFS was 25.0% (95% CI 12.8-37.3%). The median progression-free survival was 8.8 months (95% CI 0-20.3 months), and the median overall survival was 40.6 months (95% CI 22.6-58.6 months). Patients with B cell tumors who relapsed but had no B symptoms were clinical stage I/II, had infiltration fewer than two extranodal sites, had CD4⁺ counts >200 cells/μL, and had lactate dehydrogenase (LDH) less than the upper limit of normal benefited from GDP. The level of LDH had a significant impact on the response rate to chemotherapy with GDP (P = 0.015). Myelosuppression was the main side effect; the incidence of grade 3-4 anemia was 8.3%; leukopenia, 37.5%; and thrombocytopenia, 48.3%. Univariate and multivariate analyses were performed to determine variables for OS and PFS. This study confirms that GDP is an effective and safe salvage regimen in relapsed or refractory AIDS-NHL, was associated with modest declines in CD4⁺ lymphocyte counts, and did not promote HIV-1 viral replication.
Assessing the effects of legacy contaminants on egg and ...
Great Lakes Areas of Concern (AOCs) are affected by many stressors, some of which are environmental contaminants including PCBs, PBDEs, persistent organochlorine pesticides, dioxins, benzenes, and other chemicals. These toxicants can accumulate in aquatic biota and ultimately transfer to insectivorous birds that use the aquatic areas within AOCs. We used a relatively new multistate survival modeling approach to examine the relationship between avian egg and nestling survival and 11 contaminant concentrations in representative eggs of Tree Swallows (Tachycineta bicolor) nestling at reference (n=10) and contaminated sites (n=59) within 27 AOCs around the Great Lakes. A total of 1,303 nests and 7,752 eggs were included in the modeling effort. Our analyses controlled for other common sources of variation in egg survival, including female age, date within season, year, and both site and AOC. Site, date within year, year, and female age all proved to be important variables in explaining egg survival. Among environmental contaminants, we found few associations between egg and nestling failure and contaminant concentration in representative eggs. Total dioxin furan toxicity equivalents (TDFTEQ) was significantly positively associated with egg failure, but significantly negatively associated with nestling death. Across the full dose response for this contaminant, empirically observed values of TDFTEQ were concentrated at the low end, with only a few values at the
Phenotypic plasticity in a population of odonates.
Bowman, Randi M; Schmidt, Sharol; Weeks, Chelsea; Clark, Hunter; Brown, Christopher; Latta, Leigh C; Edgehouse, Michael
2018-05-31
The maintenance of phenotypic plasticity within a species ensures survival through environmental flux. Plastic strategies are increasingly important given the number and magnitude of modern anthropogenic threats to the environment. We tested for phenotypic plasticity in the odonate Argia vivida in response to resource limitation. By limiting food availability, effectively inducing hunger, we were able to quantify shifts in agonistic behavior during intraspecific interactions. Scoring behavior in one-on-one combat trials after 1 and 4 days without food revealed phenotypic plasticity. Three classes of genotypes were identified, genotypes exhibiting either increased aggression, decreased aggression, or no phenotypic plasticity, in response to resource limitation. The variable plastic strategies in this population of odonates likely aids in maintaining fitness in fluctuating environments.
Peng, Silvio; Tasara, Taurai; Hummerjohann, Jörg; Stephan, Roger
2011-05-01
The ability of foodborne pathogens to survive in certain foods mainly depends on stress response mechanisms. Insight into molecular properties enabling pathogenic bacteria to survive in food is valuable for improvement of the control of pathogens during food processing. Raw milk cheeses are a potential source for human infections with Shiga toxin-producing Escherichia coli (STEC). In this review, we focused on the stress response mechanisms important for allowing STEC to survive raw milk cheese production processes. The major components and regulation pathways for general, acid, osmotic, and heat shock stress responses in E. coli and the implications of these responses for the survival of STEC in raw milk cheeses are discussed.
Effects of Sex, Strain, and Energy Intake on Hallmarks of Aging in Mice.
Mitchell, Sarah J; Madrigal-Matute, Julio; Scheibye-Knudsen, Morten; Fang, Evandro; Aon, Miguel; González-Reyes, José A; Cortassa, Sonia; Kaushik, Susmita; Gonzalez-Freire, Marta; Patel, Bindi; Wahl, Devin; Ali, Ahmed; Calvo-Rubio, Miguel; Burón, María I; Guiterrez, Vincent; Ward, Theresa M; Palacios, Hector H; Cai, Huan; Frederick, David W; Hine, Christopher; Broeskamp, Filomena; Habering, Lukas; Dawson, John; Beasley, T Mark; Wan, Junxiang; Ikeno, Yuji; Hubbard, Gene; Becker, Kevin G; Zhang, Yongqing; Bohr, Vilhelm A; Longo, Dan L; Navas, Placido; Ferrucci, Luigi; Sinclair, David A; Cohen, Pinchas; Egan, Josephine M; Mitchell, James R; Baur, Joseph A; Allison, David B; Anson, R Michael; Villalba, José M; Madeo, Frank; Cuervo, Ana Maria; Pearson, Kevin J; Ingram, Donald K; Bernier, Michel; de Cabo, Rafael
2016-06-14
Calorie restriction (CR) is the most robust non-genetic intervention to delay aging. However, there are a number of emerging experimental variables that alter CR responses. We investigated the role of sex, strain, and level of CR on health and survival in mice. CR did not always correlate with lifespan extension, although it consistently improved health across strains and sexes. Transcriptional and metabolomics changes driven by CR in liver indicated anaplerotic filling of the Krebs cycle together with fatty acid fueling of mitochondria. CR prevented age-associated decline in the liver proteostasis network while increasing mitochondrial number, preserving mitochondrial ultrastructure and function with age. Abrogation of mitochondrial function negated life-prolonging effects of CR in yeast and worms. Our data illustrate the complexity of CR in the context of aging, with a clear separation of outcomes related to health and survival, highlighting complexities of translation of CR into human interventions. Published by Elsevier Inc.
Re-evaluating the northeastern Minnesota moose decline and the role of wolves
Mech, L. David; Fieberg, John
2014-01-01
We re-evaluated findings from Lenarz et al. (2009) that adult moose (Alces alces) survival in northeastern Minnesota was related to high January temperatures and that predation by wolves (Canis lupus) played a minor role. We found significant inverse relationships between annual wolf numbers in part of the moose range and various moose demographics from 2003 to 2013 that suggested a stronger role of wolves than heretofore believed. To re-evaluate the temperature findings, we conducted a simulation study, mimicking the approach taken by Lenarz et al. (2009), to explore the potential for concluding a significant relationship exists between temperature and survival, when no association exists. We found that the high R2s and low probabilities associated with the regression models in Lenarz et al. (2009) should be viewed cautiously in light of the large number of fitted models (m = 45) and few observations (n = 6 for each of 5 response variables).
Descriptive epidemiology of breast cancer in China: incidence, mortality, survival and prevalence.
Li, Tong; Mello-Thoms, Claudia; Brennan, Patrick C
2016-10-01
Breast cancer is the most common neoplasm diagnosed amongst women worldwide and is the leading cause of female cancer death. However, breast cancer in China is not comprehensively understood compared with Westernised countries, although the 5-year prevalence statistics indicate that approximately 11 % of worldwide breast cancer occurs in China and that the incidence has increased rapidly in recent decades. This paper reviews the descriptive epidemiology of Chinese breast cancer in terms of incidence, mortality, survival and prevalence, and explores relevant factors such as age of manifestation and geographic locations. The statistics are compared with data from the Westernised world with particular emphasis on the United States and Australia. Potential causal agents responsible for differences in breast cancer epidemiology between Chinese and other populations are also explored. The need to minimise variability and discrepancies in methods of data acquisition, analysis and presentation is highlighted.
Julianna M. A. Jenkins; Frank R. Thompson; John Faaborg
2016-01-01
We can improve our ability to assess population viability and forecast population growth under different scenarios by understanding factors that limit population parameters in each stage of the annual cycle. Postfledging mortality rates may be as variable as nest survival across regions and fragmentation gradients, although factors that negatively impact nest survival...
Schmid, Matthias; Küchenhoff, Helmut; Hoerauf, Achim; Tutz, Gerhard
2016-02-28
Survival trees are a popular alternative to parametric survival modeling when there are interactions between the predictor variables or when the aim is to stratify patients into prognostic subgroups. A limitation of classical survival tree methodology is that most algorithms for tree construction are designed for continuous outcome variables. Hence, classical methods might not be appropriate if failure time data are measured on a discrete time scale (as is often the case in longitudinal studies where data are collected, e.g., quarterly or yearly). To address this issue, we develop a method for discrete survival tree construction. The proposed technique is based on the result that the likelihood of a discrete survival model is equivalent to the likelihood of a regression model for binary outcome data. Hence, we modify tree construction methods for binary outcomes such that they result in optimized partitions for the estimation of discrete hazard functions. By applying the proposed method to data from a randomized trial in patients with filarial lymphedema, we demonstrate how discrete survival trees can be used to identify clinically relevant patient groups with similar survival behavior. Copyright © 2015 John Wiley & Sons, Ltd.
RESPONSES OF MALE TROPICAL MOCKINGBIRDS TO VARIATION IN WITHIN-SONG AND BETWEEN-SONG VERSATILITY
Botero, Carlos A.; Vehrencamp, Sandra L.
2007-01-01
Despite their large vocal repertoires and otherwise highly versatile singing style, male mockingbirds sometimes sing in a highly repetitive fashion. We conducted a playback experiment to determine the possible signal value of different syllable presentation patterns during simulated male intrusions in the Tropical Mockingbird (Mimus gilvus) testing the hypothesis that more repetitive singing represents a stronger threat and generates a stronger aggressive response. Responses were measured in terms of approach and singing behavior and were analyzed using McGregor’s (1992) multivariate method. We also introduce the use of survival analysis for analyzing response variables for which subjects do not perform the behavior in question in at least one of the replicates (known as ‘right-censored variables’ in the statistical literature). As predicted by theory, experimental subjects responded more aggressively to songs composed of a single note than to variable ones. However, versatility at the between-song level had an opposite effect as high song switching rates generated stronger responses than low ones. Given the lack of a statistical interaction between within-song versatility and switching rate, we conclude that these two parameters may serve independent purposes and possibly transmit different information. We discuss the possibility that the signal value of variation in vocal versatility lies in the mediation of territorial conflicts, the attraction of female partners and/or the mediation of conflicts over access to reproductive females. PMID:18509510
Blakely, Collin M.; Pazarentzos, Evangelos; Olivas, Victor; Asthana, Saurabh; Yan, Jenny Jiacheng; Tan, Irena; Hrustanovic, Gorjan; Chan, Elton; Lin, Luping; Neel, Dana S.; Newton, William; Bobb, Kathryn; Fouts, Timothy; Meshulam, Jeffrey; Gubens, Matthew A.; Jablons, David M.; Johnson, Jeffrey R.; Bandyopadhyay, Sourav; Krogan, Nevan J.; Bivona, Trever G.
2015-01-01
Summary Although oncogene-targeted therapy often elicits profound initial tumor responses in patients, responses are generally incomplete because some tumor cells survive initial therapy as residual disease that enables eventual acquired resistance. The mechanisms underlying tumor cell adaptation and survival during initial therapy are incompletely understood. Here, through the study of EGFR-mutant lung adenocarcinoma we show that NF-κB signaling is rapidly engaged upon initial EGFR inhibitor treatment to promote tumor cell survival and residual disease. EGFR oncogene inhibition induced an EGFR-TRAF2-RIP1-IKK complex that stimulated an NF-κB-mediated transcriptional survival program. The direct NF-κB inhibitor PBS-1086 suppressed this adaptive survival program and increased the magnitude and duration of initial EGFR inhibitor response in multiple NSCLC models, including a patient-derived xenograft. These findings unveil NF-κB activation as a critical adaptive survival mechanism engaged by EGFR oncogene inhibition and provide rationale for EGFR and NF-κB co-inhibition to eliminate residual disease and enhance patient responses. PMID:25843712
Sasaki, Koji; Kantarjian, Hagop M; Jain, Preetesh; Jabbour, Elias J; Ravandi, Farhad; Konopleva, Marina; Borthakur, Gautam; Takahashi, Koichi; Pemmaraju, Naveen; Daver, Naval; Pierce, Sherry A; O'Brien, Susan M; Cortes, Jorge E
2016-01-15
Tyrosine kinase inhibitors (TKIs) significantly improve survival in patients with chronic myeloid leukemia in chronic phase (CML-CP). Conditional probability provides survival information in patients who have already survived for a specific period of time after treatment. Cumulative response and survival data from 6 consecutive frontline TKI clinical trials were analyzed. Conditional probability was calculated for failure-free survival (FFS), transformation-free survival (TFS), event-free survival (EFS), and overall survival (OS) according to depth of response within 1 year of the initiation of TKIs, including complete cytogenetic response, major molecular response, and molecular response with a 4-log or 4.5-log reduction. A total of 483 patients with a median follow-up of 99.4 months from the initiation of treatment with TKIs were analyzed. Conditional probabilities of FFS, TFS, EFS, and OS for 1 additional year for patients alive after 12 months of therapy ranged from 92.0% to 99.1%, 98.5% to 100%, 96.2% to 99.6%, and 96.8% to 99.7%, respectively. Conditional FFS for 1 additional year did not improve with a deeper response each year. Conditional probabilities of TFS, EFS, and OS for 1 additional year were maintained at >95% during the period. In the era of TKIs, patients with chronic myeloid leukemia in chronic phase who survived for a certain number of years maintained excellent clinical outcomes in each age group. Cancer 2016;122:238-248. © 2015 American Cancer Society. © 2015 American Cancer Society.
Pediatric defibrillation after cardiac arrest: initial response and outcome
Rodríguez-Núñez, Antonio; López-Herce, Jesús; García, Cristina; Domínguez, Pedro; Carrillo, Angel; Bellón, Jose María
2006-01-01
Introduction Shockable rhythms are rare in pediatric cardiac arrest and the results of defibrillation are uncertain. The objective of this study was to analyze the results of cardiopulmonary resuscitation that included defibrillation in children. Methods Forty-four out of 241 children (18.2%) who were resuscitated from inhospital or out-of-hospital cardiac arrest had been treated with manual defibrillation. Data were recorded according to the Utstein style. Outcome variables were a sustained return of spontaneous circulation (ROSC) and one-year survival. Characteristics of patients and of resuscitation were evaluated. Results Cardiac disease was the major cause of arrest in this group. Ventricular fibrillation (VF) or pulseless ventricular tachycardia (PVT) was the first documented electrocardiogram rhythm in 19 patients (43.2%). A shockable rhythm developed during resuscitation in 25 patients (56.8%). The first shock (dose, 2 J/kg) terminated VF or PVT in eight patients (18.1%). Seventeen children (38.6%) needed more than three shocks to solve VF or PVT. ROSC was achieved in 28 cases (63.6%) and it was sustained in 19 patients (43.2%). Only three patients (6.8%), however, survived at 1-year follow-up. Children with VF or PVT as the first documented rhythm had better ROSC, better initial survival and better final survival than children with subsequent VF or PVT. Children who survived were older than the finally dead patients. No significant differences in response rate were observed when first and second shocks were compared. The survival rate was higher in patients treated with a second shock dose of 2 J/kg than in those who received higher doses. Outcome was not related to the cause or the location of arrest. The survival rate was inversely related to the duration of cardiopulmonary resuscitation. Conclusion Defibrillation is necessary in 18% of children who suffer cardiac arrest. Termination of VF or PVT after the first defibrillation dose is achieved in a low percentage of cases. Despite a sustained ROSC being obtained in more than one-third of cases, the final survival remains low. The outcome is very poor when a shockable rhythm develops during resuscitation efforts. New studies are needed to ascertain whether the new international guidelines will contribute to improve the outcome of pediatric cardiac arrest. PMID:16882339
Fernández-Chacón, Albert; Genovart, Meritxell; Álvarez, David; Cano, José M; Ojanguren, Alfredo F; Rodriguez-Muñoz, Rolando; Nicieza, Alfredo G
2015-06-01
In organisms such as fish, where body size is considered an important state variable for the study of their population dynamics, size-specific growth and survival rates can be influenced by local variation in both biotic and abiotic factors, but few studies have evaluated the complex relationships between environmental variability and size-dependent processes. We analysed a 6-year capture-recapture dataset of brown trout (Salmo trutta) collected at 3 neighbouring but heterogeneous mountain streams in northern Spain with the aim of investigating the factors shaping the dynamics of local populations. The influence of body size and water temperature on survival and individual growth was assessed under a multi-state modelling framework, an extension of classical capture-recapture models that considers the state (i.e. body size) of the individual in each capture occasion and allows us to obtain state-specific demographic rates and link them to continuous environmental variables. Individual survival and growth patterns varied over space and time, and evidence of size-dependent survival was found in all but the smallest stream. At this stream, the probability of reaching larger sizes was lower compared to the other wider and deeper streams. Water temperature variables performed better in the modelling of the highest-altitude population, explaining over a 99 % of the variability in maturation transitions and survival of large fish. The relationships between body size, temperature and fitness components found in this study highlight the utility of multi-state approaches to investigate small-scale demographic processes in heterogeneous environments, and to provide reliable ecological knowledge for management purposes.
Woods, P.F.
1985-01-01
The survival and growth rates of rainbow trout (Salmo gairdnieri) were concurrently measured with selected limnological characteristics in nine small (surface area < 25 sq hectometers) lakes in the Matanuska-Susitna Borough. The project goal was to develop empirical models for predicting rainbow trout growth rates from the following variables: total phosphorus concentration, chlorophyll a concentration, Secchi disc transparency, or the morphoedaphic index--a means of characterizing potential biological productivity. No suitable model could be developed from the data collected during 1982 and 1983. The lack of significant correlation was attributed in part to the wide variation in survival of rainbow trout. Winterkills, caused by severe depletion of dissolved oxygen, were suspected in four of the lakes. Varied levels of fishing pressure and competition with threespine stickleback (Gasterosteus aculeatus) also influenced survival of rainbow trout but their effects were overshadowed by winterkill. Predictive capability was also reduced because of inconsistencies in rankings generated by each of the four limnological variables chosen as indicators of potential biological productivity. A lake ranked low in productivity by one variable was commonly ranked high in productivity by another variable. The survivability of rainbow trout stocked in lakes such as these nine may be a more important indicator of potential biomass production than are indicators of lake fertility. Assessments of a lake 's susceptibility to winterkill and the degree of competition with threespine stickleback are suggested as important topics for additional research. (Author 's abstract)
Muths, Erin L.; Chambert, Thierry A.; Schmidt, B. R.; Miller, D. A. W.; Hossack, Blake R.; Joly, P.; Grolet, O.; Green, D. M.; Pilliod, David S.; Cheylan, M.; Fisher, Robert N.; McCaffery, R. M.; Adams, M. J.; Palen, W. J.; Arntzen, J. W.; Garwood, J.; Fellers, Gary M.; Thirion, J. M.; Grant, Evan H. Campbell; Besnard, A.
2017-01-01
The pervasive and unabated nature of global amphibian declines suggests common demographic responses to a given driver, and quantification of major drivers and responses could inform broad-scale conservation actions. We explored the influence of climate on demographic parameters (i.e., changes in the probabilities of survival and recruitment) using 31 datasets from temperate zone amphibian populations (North America and Europe) with more than a decade of observations each. There was evidence for an influence of climate on population demographic rates, but the direction and magnitude of responses to climate drivers was highly variable among taxa and among populations within taxa. These results reveal that climate drivers interact with variation in life-history traits and population-specific attributes resulting in a diversity of responses. This heterogeneity complicates the identification of conservation ‘rules of thumb’ for these taxa, and supports the notion of local focus as the most effective approach to overcome global-scale conservation challenges.
Population ecology of polar bears in Davis Strait, Canada and Greenland
Peacock, Elizabeth; Taylor, Mitchell K.; Laake, Jeffrey L.; Stirling, Ian
2013-01-01
Until recently, the sea ice habitat of polar bears was understood to be variable, but environmental variability was considered to be cyclic or random, rather than progressive. Harvested populations were believed to be at levels where density effects were considered not significant. However, because we now understand that polar bear demography can also be influenced by progressive change in the environment, and some populations have increased to greater densities than historically lower numbers, a broader suite of factors should be considered in demographic studies and management. We analyzed 35 years of capture and harvest data from the polar bear (Ursus maritimus) subpopulation in Davis Strait, including data from a new study (2005–2007), to quantify its current demography. We estimated the population size in 2007 to be 2,158 ± 180 (SE), a likely increase from the 1970s. We detected variation in survival, reproductive rates, and age-structure of polar bears from geographic sub-regions. Survival and reproduction of bears in southern Davis Strait was greater than in the north and tied to a concurrent dramatic increase in breeding harp seals (Pagophilus groenlandicus) in Labrador. The most supported survival models contained geographic and temporal variables. Harp seal abundance was significantly related to polar bear survival. Our estimates of declining harvest recovery rate, and increasing total survival, suggest that the rate of harvest declined over time. Low recruitment rates, average adult survival rates, and high population density, in an environment of high prey density, but deteriorating and variable ice conditions, currently characterize the Davis Strait polar bears. Low reproductive rates may reflect negative effects of greater densities or worsening ice conditions.
Coutand, Catherine; Chevolot, Malia; Lacointe, André; Rowe, Nick; Scotti, Ivan
2010-02-01
In rain forests, sapling survival is highly dependent on the regulation of trunk slenderness (height/diameter ratio): shade-intolerant species have to grow in height as fast as possible to reach the canopy but also have to withstand mechanical loadings (wind and their own weight) to avoid buckling. Recent studies suggest that mechanosensing is essential to control tree dimensions and stability-related morphogenesis. Differences in species slenderness have been observed among rainforest trees; the present study thus investigates whether species with different slenderness and growth habits exhibit differences in mechanosensitivity. Recent studies have led to a model of mechanosensing (sum-of-strains model) that predicts a quantitative relationship between the applied sum of longitudinal strains and the plant's responses in the case of a single bending. Saplings of five different neotropical species (Eperua falcata, E. grandiflora, Tachigali melinonii, Symphonia globulifera and Bauhinia guianensis) were subjected to a regimen of controlled mechanical loading phases (bending) alternating with still phases over a period of 2 months. Mechanical loading was controlled in terms of strains and the five species were subjected to the same range of sum of strains. The application of the sum-of-strain model led to a dose-response curve for each species. Dose-response curves were then compared between tested species. The model of mechanosensing (sum-of-strain model) applied in the case of multiple bending as long as the bending frequency was low. A comparison of dose-response curves for each species demonstrated differences in the stimulus threshold, suggesting two groups of responses among the species. Interestingly, the liana species B. guianensis exhibited a higher threshold than other Leguminosae species tested. This study provides a conceptual framework to study variability in plant mechanosensing and demonstrated interspecific variability in mechanosensing.
Hutchings, Jeffrey A
2015-01-01
Abstract The level of phenotypic plasticity displayed within a population (i.e. the slope of the reaction norm) reflects the short-term response of a population to environmental change, while variation in reaction norm slopes among populations reflects spatial variation in these responses. Thus far, studies of thermal reaction norm variation have focused on geographically driven adaptation among different latitudes, altitudes or habitats. Yet, thermal variability is a function of both space and time. For organisms that reproduce at different times of year, such variation has the potential to promote adaptive variability in thermal responses for critical early life stages. Using common-garden experiments, we examined the spatial scale of genetic variation in thermal plasticity for early life-history traits among five populations of endangered Atlantic cod (Gadus morhua) that spawn at different times of year. Patterns of plasticity for larval growth and survival suggest that population responses to climate change will differ substantially, with increasing water temperatures posing a considerably greater threat to autumn-spawning cod than to those that spawn in winter or spring. Adaptation to seasonal cooling or warming experienced during the larval stage is suggested as a possible cause. Furthermore, populations that experience relatively cold temperatures during early life might be more sensitive to changes in temperature. Substantial divergence in adaptive traits was evident at a smaller spatial scale than has previously been shown for a marine fish with no apparent physical barriers to gene flow (∼200 km). Our findings highlight the need to consider the impact of intraspecific variation in reproductive timing on thermal adaptation when forecasting the effects of climate change on animal populations. PMID:27293712
Oomen, Rebekah A; Hutchings, Jeffrey A
2015-01-01
The level of phenotypic plasticity displayed within a population (i.e. the slope of the reaction norm) reflects the short-term response of a population to environmental change, while variation in reaction norm slopes among populations reflects spatial variation in these responses. Thus far, studies of thermal reaction norm variation have focused on geographically driven adaptation among different latitudes, altitudes or habitats. Yet, thermal variability is a function of both space and time. For organisms that reproduce at different times of year, such variation has the potential to promote adaptive variability in thermal responses for critical early life stages. Using common-garden experiments, we examined the spatial scale of genetic variation in thermal plasticity for early life-history traits among five populations of endangered Atlantic cod (Gadus morhua) that spawn at different times of year. Patterns of plasticity for larval growth and survival suggest that population responses to climate change will differ substantially, with increasing water temperatures posing a considerably greater threat to autumn-spawning cod than to those that spawn in winter or spring. Adaptation to seasonal cooling or warming experienced during the larval stage is suggested as a possible cause. Furthermore, populations that experience relatively cold temperatures during early life might be more sensitive to changes in temperature. Substantial divergence in adaptive traits was evident at a smaller spatial scale than has previously been shown for a marine fish with no apparent physical barriers to gene flow (∼200 km). Our findings highlight the need to consider the impact of intraspecific variation in reproductive timing on thermal adaptation when forecasting the effects of climate change on animal populations.
USDA-ARS?s Scientific Manuscript database
Adult house flies ingest variable numbers of bacteria when they encounter microbe-rich substrates. Bacterial abundance may affect survival within the fly gut, which subsequently impacts vector potential. This study investigated the dose-dependent survival of GFP-expressing Salmonella enterica serova...
Hung, Giun-Yi; Yen, Hsiu-Ju; Yen, Chueh-Chuan; Wu, Po-Kuei; Chen, Cheng-Fong; Chen, Paul C-H; Wu, Hung-Ta H; Chiou, Hong-Jen; Chen, Wei-Ming
2016-04-01
The aim of this study was to compare survival before and after 2004 and define the prognostic factors for high-grade osteosarcomas beyond those of typical young patients with localized extremity disease. Few studies have reported the long-term treatment outcomes of high-grade osteosarcoma in Taiwan. A total of 202 patients with primary high-grade osteosarcoma who received primary chemotherapy at Taipei Veterans General Hospital between January 1995 and December 2011 were retrospectively evaluated and compared by period (1995-2003 vs 2004-2011). Patients of all ages and tumor sites and those following or not following controlled protocols were included in analysis of demographic, tumor-related, and treatment-related variables and survival. Overall survival and progression-free survival at 5 years were, respectively, 67.7% and 48% for all patients (n = 202), 77.3% and 57.1% for patients without metastasis (n = 157), and 33.9% and 14.8% for patients with metastasis (n = 45). The survival rates of patients treated after 2004 were significantly higher (by 13%-16%) compared with those of patients treated before 2004, with an accompanying 30% increase in histological good response rate (P = .002). Factors significantly contributing to inferior survival in univariate and multivariate analyses were diagnosis before 2004, metastasis at diagnosis, and being a noncandidate for a controlled treatment protocol. By comparison with the regimens used at our institution before 2004, the current results support the effectiveness of the post-2004 regimens, which consisted of substantially reduced cycles of high-dose methotrexate and a higher dosage of ifosfamide per cycle, cisplatin, and doxorubicin, for treating high-grade osteosarcoma in Asian patients.
Benson, Thomas J; Chiavacci, Scott J; Ward, Michael P
2013-06-01
Declines of migratory birds have led to increased focus on causative factors for these declines, including the potential adverse effects of habitat fragmentation on reproductive success. Although numerous studies have addressed how proximity to a habitat edge, patch size, or landscape context influence nest survival or brood parasitism, many have failed to find the purported effects. Furthermore, many have sought to generalize patterns across large geographic areas and habitats. Here, we examined evidence for effects of edge proximity, patch size, and landscape context on nest survival and brood parasitism of grassland birds, a group of conservation concern. The only consistent effect was a positive association between edge proximity and brood parasitism. We examined effects of patch size on nest survival (37 studies) and brood parasitism (30 studies) representing 170 and 97 different estimates, respectively, with a total sample size of > 14000 nests spanning eastern North America. Nest survival weakly increased with patch size in the Great Plains, but not in the Midwestern or Eastern United States, and brood parasitism was inversely related to patch size and consistently greater in the Great Plains. The consistency in brood parasitism relative to nest survival patterns is likely due to parasitism being caused by one species, while nest survival is driven by a diverse and variable suite of nest predators. Often, studies assume that predators responsible for nest predation, the main driver of nest success, either are the same or exhibit the same behaviors across large geographic areas. These results suggest that a better mechanistic understanding of nest predation is needed to provide meaningful conservation recommendations for improving grassland bird productivity, and that the use of general recommendations across large geographic areas should only be undertaken when sufficient data are available from all regions.
Farr, Alex; Stolz, Myriam; Baumann, Lukas; Bago-Horvath, Zsuzsanna; Oppolzer, Elisabeth; Pfeiler, Georg; Seifert, Michael; Singer, Christian F
2017-06-01
The effect of obesity in breast cancer patients undergoing neoadjuvant chemotherapy (NAC) remains controversial. The aim of this study was to determine the obesity-related effect on pathological complete response (pCR) and survival in women receiving full uncapped doses of NAC. We retrospectively analyzed the data of all consecutive women who underwent anthracycline-taxane-based NAC for primary breast cancer between 2005 and 2015 at the Department of Obstetrics and Gynecology, Medical University of Vienna. Following the WHO criteria, women with a body mass index (BMI) ≥30 kg/m 2 at baseline were considered obese, whereas those with a BMI <30 kg/m 2 were considered non-obese. Those with dose reductions or dose capping were not eligible for study inclusion. Cox regression and logistic regression were performed. The Kaplan-Meier method was used to analyze disease-free, progression-free, and overall survival. The pCR served as the main outcome measure. Among 120 women who received neoadjuvant epirubicin plus cyclophosphamide and docetaxel, 28 (23.3%) were obese and 92 (76.7%) were non-obese. In the multivariate logistic regression model that adjusted for potentially confounding variables, obesity had an independent positive predictive effect on pCR (OR 4.29, 95% CI, 1.42-13.91; p = 0.011), which was significant in the postmenopausal subgroup (OR 4.72, 95% CI, 1.47-15.84; p = 0.01). When comparing non-obese with obese women, we found that obese women experienced longer progression-free survival (HR 0.10, 95% CI, 8.448 × 10 -4 -0.81; p = 0.025). Obese women receiving full uncapped doses of anthracycline-taxane-based NAC have increased pCR and favorable progression-free survival. This could result from increased dose intensity with increased efficacy and toxicity. Copyright © 2017 Elsevier Ltd. All rights reserved.
Frantz, Mack W.; Wood, Petra B.; Sheehan, James; George, Gregory
2018-01-01
Shale gas development continues to outpace the implementation of best management practices for wildlife affected by development. We examined demographic responses of the Louisiana Waterthrush (Parkesia motacilla) to shale gas development during 2009–2011 and 2013–2015 in a predominantly forested landscape in West Virginia, USA. Forest cover across the study area decreased from 95% in 2008 to 91% in 2015, while the area affected by shale gas development increased from 0.4% to 3.9%. We quantified nest survival and productivity, a source–sink threshold, riparian habitat quality, territory density, and territory length by monitoring 58.1 km of forested headwater streams (n = 14 streams). Across years, we saw annual variability in nest survival, with a general declining trend over time. Of 11 a priori models tested to explain nest survival (n = 280 nests), 4 models that included temporal, habitat, and shale gas covariates were supported, and 2 of these models accounted for most of the variation in daily nest survival rate. After accounting for temporal effects (rainfall, nest age, and time within season), shale gas development had negative effects on nest survival. Population-level nest productivity declined and individual productivity was lower in areas disturbed by shale gas development than in undisturbed areas, and a source–sink threshold suggested that disturbed areas were more at risk of being sink habitat. Riparian habitat quality scores, as measured by a U.S. Environmental Protection Agency index and a waterthrush-specific habitat suitability index, differed by year and were negatively related to the amount of each territory disturbed by shale gas development. Territory density was not related to the amount of shale gas disturbance, but decreased over time as territory lengths increased. Overall, our results suggest a decline in waterthrush site quality as shale gas development increases, despite relatively small site-wide forest loss.
Lustosa de Sousa, Daniel Willian; de Almeida Ferreira, Francisco Valdeci; Cavalcante Félix, Francisco Helder; de Oliveira Lopes, Marcos Vinicios
2015-01-01
Objective To describe the clinical and laboratory features of children and adolescents with acute lymphoblastic leukemia treated at three referral centers in Ceará and evaluate prognostic factors for survival, including age, gender, presenting white blood cell count, immunophenotype, DNA index and early response to treatment. Methods Seventy-six under 19-year-old patients with newly diagnosed acute lymphoblastic leukemia treated with the Grupo Brasileiro de Tratamento de Leucemia da Infância – acute lymphoblastic leukemia-93 and -99 protocols between September 2007 and December 2009 were analyzed. The diagnosis was based on cytological, immunophenotypic and cytogenetic criteria. Associations between variables, prognostic factors and response to treatment were analyzed using the chi-square test and Fisher's exact test. Overall and event-free survival were estimated by Kaplan–Meier analysis and compared using the log-rank test. A Cox proportional hazards model was used to identify independent prognostic factors. Results The average age at diagnosis was 6.3 ± 0.5 years and males were predominant (65%). The most frequently observed clinical features were hepatomegaly, splenomegaly and lymphadenopathy. Central nervous system involvement and mediastinal enlargement occurred in 6.6% and 11.8%, respectively. B-acute lymphoblastic leukemia was more common (89.5%) than T-acute lymphoblastic leukemia. A DNA index >1.16 was found in 19% of patients and was associated with favorable prognosis. On Day 8 of induction therapy, 95% of the patients had lymphoblast counts <1000/μL and white blood cell counts <5.0 × 109/L. The remission induction rate was 95%, the induction mortality rate was 2.6% and overall survival was 72%. Conclusion The prognostic factors identified are compatible with the literature. The 5-year overall and event-free survival rates were lower than those reported for developed countries. As shown by the multivariate analysis, age and baseline white blood cell count were independent prognostic factors. PMID:26190424
Arendt, Michael D.; Schwenter, Jeffrey A.; Witherington, Blair E.; Meylan, Anne B.; Saba, Vincent S.
2013-01-01
A recent analysis suggested that historical climate forcing on the oceanic habitat of neonate sea turtles explained two-thirds of interannual variability in contemporary loggerhead (Caretta caretta) sea turtle nest counts in Florida, where nearly 90% of all nesting by this species in the Northwest Atlantic Ocean occurs. Here, we show that associations between annual nest counts and climate conditions decades prior to nest counts and those conditions one year prior to nest counts were not significantly different. Examination of annual nest count and climate data revealed that statistical artifacts influenced the reported 31-year lag association with nest counts. The projected importance of age 31 neophytes to annual nest counts between 2020 and 2043 was modeled using observed nest counts between 1989 and 2012. Assuming consistent survival rates among cohorts for a 5% population growth trajectory and that one third of the mature female population nests annually, the 41% decline in annual nest counts observed during 1998–2007 was not projected for 2029–2038. This finding suggests that annual nest count trends are more influenced by remigrants than neophytes. Projections under the 5% population growth scenario also suggest that the Peninsular Recovery Unit could attain the demographic recovery criteria of 106,100 annual nests by 2027 if nest counts in 2019 are at least comparable to 2012. Because the first year of life represents only 4% of the time elapsed through age 31, cumulative survival at sea across decades explains most cohort variability, and thus, remigrant population size. Pursuant to the U.S. Endangered Species Act, staggered implementation of protection measures for all loggerhead life stages has taken place since the 1970s. We suggest that the 1998–2007 nesting decline represented a lagged perturbation response to historical anthropogenic impacts, and that subsequent nest count increases since 2008 reflect a potential recovery response. PMID:24339901
Arendt, Michael D; Schwenter, Jeffrey A; Witherington, Blair E; Meylan, Anne B; Saba, Vincent S
2013-01-01
A recent analysis suggested that historical climate forcing on the oceanic habitat of neonate sea turtles explained two-thirds of interannual variability in contemporary loggerhead (Caretta caretta) sea turtle nest counts in Florida, where nearly 90% of all nesting by this species in the Northwest Atlantic Ocean occurs. Here, we show that associations between annual nest counts and climate conditions decades prior to nest counts and those conditions one year prior to nest counts were not significantly different. Examination of annual nest count and climate data revealed that statistical artifacts influenced the reported 31-year lag association with nest counts. The projected importance of age 31 neophytes to annual nest counts between 2020 and 2043 was modeled using observed nest counts between 1989 and 2012. Assuming consistent survival rates among cohorts for a 5% population growth trajectory and that one third of the mature female population nests annually, the 41% decline in annual nest counts observed during 1998-2007 was not projected for 2029-2038. This finding suggests that annual nest count trends are more influenced by remigrants than neophytes. Projections under the 5% population growth scenario also suggest that the Peninsular Recovery Unit could attain the demographic recovery criteria of 106,100 annual nests by 2027 if nest counts in 2019 are at least comparable to 2012. Because the first year of life represents only 4% of the time elapsed through age 31, cumulative survival at sea across decades explains most cohort variability, and thus, remigrant population size. Pursuant to the U.S. Endangered Species Act, staggered implementation of protection measures for all loggerhead life stages has taken place since the 1970s. We suggest that the 1998-2007 nesting decline represented a lagged perturbation response to historical anthropogenic impacts, and that subsequent nest count increases since 2008 reflect a potential recovery response.
Santillán, Orlando; Ramírez-Romero, Miguel A; Lozano, Luis; Checa, Alberto; Encarnación, Sergio M; Dávila, Guillermo
2016-01-01
Sigma factors are RNA polymerase subunits engaged in promoter recognition and DNA strand separation during transcription initiation in bacteria. Primary sigma factors are responsible for the expression of housekeeping genes and are essential for survival. RpoD, the primary sigma factor of Escherichia coli, a γ-proteobacteria, recognizes consensus promoter sequences highly similar to those of some α-proteobacteria species. Despite this resemblance, RpoD is unable to sustain transcription from most of the α-proteobacterial promoters tested so far. In contrast, we have found that SigA, the primary sigma factor of Rhizobium etli, an α-proteobacteria, is able to transcribe E. coli promoters, although it exhibits only 48% identity (98% coverage) to RpoD. We have called this the transcriptional laxity phenomenon. Here, we show that SigA partially complements the thermo-sensitive deficiency of RpoD285 from E. coli strain UQ285 and that the SigA region σ4 is responsible for this phenotype. Sixteen out of 74 residues (21.6%) within region σ4 are variable between RpoD and SigA. Mutating these residues significantly improves SigA ability to complement E. coli UQ285. Only six of these residues fall into positions already known to interact with promoter DNA and to comprise a helix-turn-helix motif. The remaining variable positions are located on previously unexplored sites inside region σ4, specifically into the first two α-helices of the region. Neither of the variable positions confined to these helices seem to interact directly with promoter sequence; instead, we adduce that these residues participate allosterically by contributing to correct region folding and/or positioning of the HTH motif. We propose that transcriptional laxity is a mechanism for ensuring transcription in spite of naturally occurring mutations from endogenous promoters and/or horizontally transferred DNA sequences, allowing survival and fast environmental adaptation of α-proteobacteria.
Mack, Philip C; Gandara, David R; Lara, Primo N
2012-12-01
Historically, notable variability has been observed in clinical trial outcomes between different regions and populations worldwide, even when employing the same cytotoxic regimen in lung cancer. These divergent results underscore the inherent challenges in interpreting trials conducted abroad and raise questions regarding the general applicability of transnational clinical trials. Various reasons have been postulated to account for these differences in efficacy and toxicity, including trial design, eligibility criteria, patient demographics and, perhaps most intriguingly, population-related pharmacogenomics. However, without methodology to control for such variables, these hypotheses remain largely untested. The authors previously developed the 'common arm' approach in order to directly compare efficacy and toxicity results of trials simultaneously performed in different countries. By standardizing clinical trial-associated variables such as treatment regimens (dose, schedule, and so on), eligibility, staging, response and toxicity criteria, this approach has the potential to determine the underlying reasons for divergences in trial outcomes across countries, and whether population-associated polymorphisms contribute to these differences. In the past decade, Japanese and US investigators have applied the common arm analytic method to trials in both extensive-stage small-cell lung cancer (SCLC) and advanced nonSCLC. In the SCLC analysis, a comparison of the cisplatin/irinotecan arms from both trials revealed significant differences in response rates and overall survival. Significant differences were also observed in the distribution of gender and performance status. The common arm analysis in nonSCLC included two trials from Japan and one from the USA, each containing a 'common' carboplatin/paclitaxel arm. Clinical results were similar in the two Japanese trials, but were significantly different from the US trial with regard to survival, neutropenia, febrile neutropenia and anemia. The underlying basis for these divergent outcomes is discussed. The common arm methodology provides a template for identifying and interpreting patient outcome differences across populations, and is an instructive lesson in the burgeoning era of clinical trials globalization.
Santillán, Orlando; Ramírez-Romero, Miguel A.; Lozano, Luis; Checa, Alberto; Encarnación, Sergio M.; Dávila, Guillermo
2016-01-01
Sigma factors are RNA polymerase subunits engaged in promoter recognition and DNA strand separation during transcription initiation in bacteria. Primary sigma factors are responsible for the expression of housekeeping genes and are essential for survival. RpoD, the primary sigma factor of Escherichia coli, a γ-proteobacteria, recognizes consensus promoter sequences highly similar to those of some α-proteobacteria species. Despite this resemblance, RpoD is unable to sustain transcription from most of the α-proteobacterial promoters tested so far. In contrast, we have found that SigA, the primary sigma factor of Rhizobium etli, an α-proteobacteria, is able to transcribe E. coli promoters, although it exhibits only 48% identity (98% coverage) to RpoD. We have called this the transcriptional laxity phenomenon. Here, we show that SigA partially complements the thermo-sensitive deficiency of RpoD285 from E. coli strain UQ285 and that the SigA region σ4 is responsible for this phenotype. Sixteen out of 74 residues (21.6%) within region σ4 are variable between RpoD and SigA. Mutating these residues significantly improves SigA ability to complement E. coli UQ285. Only six of these residues fall into positions already known to interact with promoter DNA and to comprise a helix-turn-helix motif. The remaining variable positions are located on previously unexplored sites inside region σ4, specifically into the first two α-helices of the region. Neither of the variable positions confined to these helices seem to interact directly with promoter sequence; instead, we adduce that these residues participate allosterically by contributing to correct region folding and/or positioning of the HTH motif. We propose that transcriptional laxity is a mechanism for ensuring transcription in spite of naturally occurring mutations from endogenous promoters and/or horizontally transferred DNA sequences, allowing survival and fast environmental adaptation of α-proteobacteria. PMID:27468278
Contributions of vital rates to growth of a protected population of American black bears
Mitchell, M.S.; Pacifici, L.B.; Grand, J.B.; Powell, R.A.
2009-01-01
Analyses of large, long-lived animals suggest that adult survival generally has the potential to contribute more than reproduction to population growth rate (??), but because survival varies little, high variability in reproduction can have a greater influence. This pattern has been documented for several species of large mammals, but few studies have evaluated such contributions of vital rates to ?? for American black bears (Ursus americanus). We used variance-based perturbation analyses (life table response experiments, LTRE) and analytical sensitivity and elasticity analyses to examine the actual and potential contributions of variation of vital rates to variation in growth rate (??) of a population of black bears inhabiting the Pisgah Bear Sanctuary in the southern Appalachian Mountains of North Carolina, using a 22-year dataset. We found that recruitment varied more than other vital rates; LTRE analyses conducted over several time intervals thus indicated that recruitment generally contributed at least as much as juvenile and adult survival to observed variation in ??, even though the latter 2 vital rates had the greater potential to affect ??. Our findings are consistent with predictions from studies on polar bears (U. maritimus) and grizzly bears (U. arctos), but contrast with the few existing studies on black bears in ways that suggest levels of protection from human-caused mortality might explain whether adult survival or recruitment contribute most to variation in ?? for this species. We hypothesize that ?? is most strongly influenced by recruitment in protected populations where adult survival is relatively high and constant, whereas adult survival will most influence ?? for unprotected populations. ?? 2009 International Association for Bear Research and Management.
Mixed-grass prairie passerines exhibit weak and variable responses to patch size
Davis, S.K.; Brigham, R.M.; Shaffer, T.L.; James, P.C.
2006-01-01
Much of our current understanding of the demographic effects of habitat fragmentation on bird populations is derived from studies of passerines in forests and tallgrass prairie surrounded by woody vegetation. We quantified grassland bird density, nest survival, and productivity in 41 native mixed-grass prairie pastures during 1997-2000 in southern Saskatchewan, Canada. Pastures ranged in size from 18 ha to 11,600 ha and were typically surrounded by agriculture (i.e., ranching and annual cropping). Grassland passerines did not respond strongly or uniformly to patch size. Sprague's Pipit (Anthus spragueii) was the only species whose density increased with pasture size. Patch size had minimal influence on nest survival of Sprague's Pipit or Clay-colored Sparrow (Spizella pallida); whereas nest survival increased with patch size for Savannah Sparrow (Passerculus sandwichensis) and declined for Baird's Sparrow (Ammodramus bairdii), Chestnut-collared Longspur (Calcarius ornatus), and Western Meadowlark (Sturnella neglecta). Time-specific factors (i.e., nest age, date, and year) were more important predictors of nest survival than patch size. Exploratory analyses indicated that effects of edge distance, pasture shape, or landscape on nest survival were just as likely as patch-size effects. However, effects of edge on Chestnut-collared Longspurs may be governed by landscape-level factors, because nest survival decreased with distance to edge in landscapes with increased amounts of cropland. Our results indicate that mixed-grass prairie parcels ≥18 ha play a role in the conservation of several grassland passerine species currently in decline, but the conservation of Sprague's Pipit likely depends on maintaining larger tracts of native prairie.
Estimating piecewise exponential frailty model with changing prior for baseline hazard function
NASA Astrophysics Data System (ADS)
Thamrin, Sri Astuti; Lawi, Armin
2016-02-01
Piecewise exponential models provide a very flexible framework for modelling univariate survival data. It can be used to estimate the effects of different covariates which are influenced by the survival data. Although in a strict sense it is a parametric model, a piecewise exponential hazard can approximate any shape of a parametric baseline hazard. In the parametric baseline hazard, the hazard function for each individual may depend on a set of risk factors or explanatory variables. However, it usually does not explain all such variables which are known or measurable, and these variables become interesting to be considered. This unknown and unobservable risk factor of the hazard function is often termed as the individual's heterogeneity or frailty. This paper analyses the effects of unobserved population heterogeneity in patients' survival times. The issue of model choice through variable selection is also considered. A sensitivity analysis is conducted to assess the influence of the prior for each parameter. We used the Markov Chain Monte Carlo method in computing the Bayesian estimator on kidney infection data. The results obtained show that the sex and frailty are substantially associated with survival in this study and the models are relatively quite sensitive to the choice of two different priors.
Rubin, Samuel J; Kirke, Diana N; Ezzat, Waleed H; Truong, Minh T; Salama, Andrew R; Jalisi, Scharukh
Determine whether marital status is a significant predictor of survival in human papillomavirus-positive oropharyngeal cancer. A single center retrospective study included patients diagnosed with human papilloma virus-positive oropharyngeal cancer at Boston Medical Center between January 1, 2010 and December 30, 2015, and initiated treatment with curative intent at Boston Medical Center. Demographic data and tumor-related variables were recorded. Univariate analysis was performed using a two-sample t-test, chi-squared test, Fisher's exact test, and Kaplan Meier curves with a log rank test. Multivariate survival analysis was performed using a Cox regression model. A total of 65 patients were included in the study with 24 patients described as married and 41 patients described as single. There was no significant difference in most demographic variables or tumor related variables between the two study groups, except single patients were significantly more likely to have government insurance (p=0.0431). Furthermore, there was no significant difference in 3-year overall survival between married patients and single patients (married=91.67% vs single=87.80%; p=0.6532) or 3-year progression free survival (married=79.17% vs single=85.37%; p=0.8136). After adjusting for confounders including age, sex, race, insurance type, smoking status, treatment, and AJCC combined pathologic stage, marital status was not a significant predictor of survival [HR=0.903; 95% CI (0.126,6.489); p=0.9192]. Although previous literature has demonstrated that married patients with head and neck cancer have a survival benefit compared to single patients with head and neck cancer, we were unable to demonstrate the same survival benefit in a cohort of patients with human papilloma virus-positive oropharyngeal cancer. Copyright © 2017 Elsevier Inc. All rights reserved.
Recruitment Variability in North Atlantic Cod and Match-Mismatch Dynamics
Kristiansen, Trond; Drinkwater, Kenneth F.; Lough, R. Gregory; Sundby, Svein
2011-01-01
Background Fisheries exploitation, habitat destruction, and climate are important drivers of variability in recruitment success. Understanding variability in recruitment can reveal mechanisms behind widespread decline in the abundance of key species in marine and terrestrial ecosystems. For fish populations, the match-mismatch theory hypothesizes that successful recruitment is a function of the timing and duration of larval fish abundance and prey availability. However, the underlying mechanisms of match-mismatch dynamics and the factors driving spatial differences between high and low recruitment remain poorly understood. Methodology/Principal Findings We used empirical observations of larval fish abundance, a mechanistic individual-based model, and a reanalysis of ocean temperature data from 1960 to 2002 to estimate the survival of larval cod (Gadus morhua). From the model, we quantified how survival rates changed during the warmest and coldest years at four important cod spawning sites in the North Atlantic. The modeled difference in survival probability was not large for any given month between cold or warm years. However, the cumulative effect of higher growth rates and survival through the entire spawning season in warm years was substantial with 308%, 385%, 154%, and 175% increases in survival for Georges Bank, Iceland, North Sea, and Lofoten cod stocks, respectively. We also found that the importance of match-mismatch dynamics generally increased with latitude. Conclusions/Significance Our analyses indicate that a key factor for enhancing survival is the duration of the overlap between larval and prey abundance and not the actual timing of the peak abundance. During warm years, the duration of the overlap between larval fish and their prey is prolonged due to an early onset of the spring bloom. This prolonged season enhances cumulative growth and survival, leading to a greater number of large individuals with enhanced potential for survival to recruitment. PMID:21408215
Monticelli, David; Ramos, Jaime A.; Hines, James E.; Nichols, James D.; Spendelow, Jeffrey A.
2008-01-01
Many demographic studies on long-lived seabirds have focused on the estimation of adult survival, but much less is known about survival during the early years of life, especially in tropical species. We report analyses of a capture–recapture dataset of 685 roseate terns ringed as fledglings and adults between 1998 and 2005 on Aride Island, Seychelles, and recaptured/resighted at the same colony site over a 5 yr (2002 to 2006) period. A multistate model was used to estimate survival for different age classes, including juvenile (first-year) birds returning as non-breeding prospectors. The effect of infestation by parasites (ticks) on survival was also examined. Overall, the estimated return of first-year individuals to the natal colony was very variable, ranging from 2 to 22%. Conditioned on survival, the probability of returning from Age 2 yr onwards increased to 70%. Survival rates were best modeled as time-specific, with estimates varying from 0.02 to 1.00 (mean 0.69) in first-year birds with a marked negative effect of tick infestation. In older birds (minimum age of 2 yr), the annual estimates fell between 0.69 and 0.86 (mean 0.77). Using a components of variance approach for estimation of year-to-year variation, we found high temporal variability for first-year individuals (coefficient of variation [CV] = 65%) compared to much less variation in the survival rate of older birds (CV = 9%). These findings agree with the life-history prediction that demographic rates of juveniles are usually lower and more variable than those of older individuals. Our results are also consistent with the predicted negative effect of tick parasitism on juvenile survival. Compared with data from other roseate tern populations, survival over the first 2 yr (Age 0 to 2 yr) was 18 to 40% higher in this study, suggesting that a high ‘young’ survival rate may be an important demographic trait in this tropical population to compensate for the low annual reproductive success. Our data show that estimating survival of young individuals may be crucial to elucidating the demographic tactics of seabirds.
Remontet, Laurent; Uhry, Zoé; Bossard, Nadine; Iwaz, Jean; Belot, Aurélien; Danieli, Coraline; Charvat, Hadrien; Roche, Laurent
2018-01-01
Cancer survival trend analyses are essential to describe accurately the way medical practices impact patients' survival according to the year of diagnosis. To this end, survival models should be able to account simultaneously for non-linear and non-proportional effects and for complex interactions between continuous variables. However, in the statistical literature, there is no consensus yet on how to build such models that should be flexible but still provide smooth estimates of survival. In this article, we tackle this challenge by smoothing the complex hypersurface (time since diagnosis, age at diagnosis, year of diagnosis, and mortality hazard) using a multidimensional penalized spline built from the tensor product of the marginal bases of time, age, and year. Considering this penalized survival model as a Poisson model, we assess the performance of this approach in estimating the net survival with a comprehensive simulation study that reflects simple and complex realistic survival trends. The bias was generally small and the root mean squared error was good and often similar to that of the true model that generated the data. This parametric approach offers many advantages and interesting prospects (such as forecasting) that make it an attractive and efficient tool for survival trend analyses.
Ma, Jinbo; Wang, Zhaoyang; Wang, Chengde; Chen, Ercheng; Dong, Yaozong; Song, Yipeng; Wang, Wei; You, Dong; Jiang, Wei; Zang, Rukun
2017-02-01
To determine whether individualized radiation dose escalation after planned chemoradiation based on the decrease in tumor and normal tissue constraints can improve survival in patients with esophageal carcinoma. From August 2005 to December 2010, 112 patients with squamous esophageal carcinoma were treated with radical concurrent chemoradiation. Patients received positron emission tomography-computer tomography scan twice, before radiation and after radiation dose of 50.4 Gy. All patients were noncomplete metabolic response groups according to the Response Evaluation Criteria in solid tumors. Only 52 patients with noncomplete metabolic response received individualized dose escalation based on tumor and normal tissue constraints. Survival and treatment failure were observed and analyzed using SPSS (13.0). The rate of complete metabolic response for patients with noncomplete metabolic response after dose escalation reached 17.3% (9 of 52). The 2-year overall survival rates for patients with noncomplete metabolic response in the conventional and dose-escalation groups were 20.5% and 42.8%, respectively( P = .001). The 2-year local control rates for patients were 35.7% and 76.2%, respectively ( P = .002). When patients were classified into partial metabolic response and no metabolic response, 2-year overall survival rates for patients with partial metabolic response were significantly different in conventional and dose-escalation groups (33.8% vs 78.4%; P = .000). The 2-year overall survival rates for patients with no metabolic response in two groups (8.6% vs 15.1%) did not significantly differ ( P = .917). Individualized radiation dose escalation has the potential to improve survival in patients with esophageal carcinoma according to increased rate of complete metabolic response. However, further trials are needed to confirm this and to identify patients who may benefit from dose escalation.
Sparks, Morgan M; Westley, Peter A H; Falke, Jeffrey A; Quinn, Thomas P
2017-12-01
An important unresolved question is how populations of coldwater-dependent fishes will respond to rapidly warming water temperatures. For example, the culturally and economically important group, Pacific salmon (Oncorhynchus spp.), experience site-specific thermal regimes during early development that could be disrupted by warming. To test for thermal local adaptation and heritable phenotypic plasticity in Pacific salmon embryos, we measured the developmental rate, survival, and body size at hatching in two populations of sockeye salmon (Oncorhynchus nerka) that overlap in timing of spawning but incubate in contrasting natural thermal regimes. Using a split half-sibling design, we exposed embryos of 10 families from each of two populations to variable and constant thermal regimes. These represented both experienced temperatures by each population, and predicted temperatures under plausible future conditions based on a warming scenario from the downscaled global climate model (MIROC A1B scenario). We did not find evidence of thermal local adaptation during the embryonic stage for developmental rate or survival. Within treatments, populations hatched within 1 day of each other, on average, and among treatments, did not differ in survival in response to temperature. We did detect plasticity to temperature; embryos developed 2.5 times longer (189 days) in the coolest regime compared to the warmest regime (74 days). We also detected variation in developmental rates among families within and among temperature regimes, indicating heritable plasticity. Families exhibited a strong positive relationship between thermal variability and phenotypic variability in developmental rate but body length and mass at hatching were largely insensitive to temperature. Overall, our results indicated a lack of thermal local adaptation, but a presence of plasticity in populations experiencing contrasting conditions, as well as family-specific heritable plasticity that could facilitate adaptive change. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.
Sparks, Morgan M.; Westley, Peter A. H.; Falke, Jeffrey A.; Quinn, Thomas P.
2017-01-01
An important unresolved question is how populations of coldwater-dependent fishes will respond to rapidly warming water temperatures. For example, the culturally and economically important group, Pacific salmon (Oncorhynchus spp.), experience site-specific thermal regimes during early development that could be disrupted by warming. To test for thermal local adaptation and heritable phenotypic plasticity in Pacific salmon embryos, we measured the developmental rate, survival, and body size at hatching in two populations of sockeye salmon (Oncorhynchus nerka) that overlap in timing of spawning but incubate in contrasting natural thermal regimes. Using a split half-sibling design, we exposed embryos of 10 families from each of two populations to variable and constant thermal regimes. These represented both experienced temperatures by each population, and predicted temperatures under plausible future conditions based on a warming scenario from the downscaled global climate model (MIROC A1B scenario). We did not find evidence of thermal local adaptation during the embryonic stage for developmental rate or survival. Within treatments, populations hatched within 1 day of each other, on average, and amongtreatments, did not differ in survival in response to temperature. We did detect plasticity to temperature; embryos developed 2.5 times longer (189 days) in the coolest regime compared to the warmest regime (74 days). We also detected variation in developmental rates among families within and among temperature regimes, indicating heritable plasticity. Families exhibited a strong positive relationship between thermal variability and phenotypic variability in developmental rate but body length and mass at hatching were largely insensitive to temperature. Overall, our results indicated a lack of thermal local adaptation, but a presence of plasticity in populations experiencing contrasting conditions, as well as family-specific heritable plasticity that could facilitate adaptive change.
Kroeker, Kristy J; Kordas, Rebecca L; Crim, Ryan; Hendriks, Iris E; Ramajo, Laura; Singh, Gerald S; Duarte, Carlos M; Gattuso, Jean-Pierre
2013-01-01
Ocean acidification represents a threat to marine species worldwide, and forecasting the ecological impacts of acidification is a high priority for science, management, and policy. As research on the topic expands at an exponential rate, a comprehensive understanding of the variability in organisms' responses and corresponding levels of certainty is necessary to forecast the ecological effects. Here, we perform the most comprehensive meta-analysis to date by synthesizing the results of 228 studies examining biological responses to ocean acidification. The results reveal decreased survival, calcification, growth, development and abundance in response to acidification when the broad range of marine organisms is pooled together. However, the magnitude of these responses varies among taxonomic groups, suggesting there is some predictable trait-based variation in sensitivity, despite the investigation of approximately 100 new species in recent research. The results also reveal an enhanced sensitivity of mollusk larvae, but suggest that an enhanced sensitivity of early life history stages is not universal across all taxonomic groups. In addition, the variability in species' responses is enhanced when they are exposed to acidification in multi-species assemblages, suggesting that it is important to consider indirect effects and exercise caution when forecasting abundance patterns from single-species laboratory experiments. Furthermore, the results suggest that other factors, such as nutritional status or source population, could cause substantial variation in organisms' responses. Last, the results highlight a trend towards enhanced sensitivity to acidification when taxa are concurrently exposed to elevated seawater temperature. PMID:23505245
Kroeker, Kristy J; Kordas, Rebecca L; Crim, Ryan; Hendriks, Iris E; Ramajo, Laura; Singh, Gerald S; Duarte, Carlos M; Gattuso, Jean-Pierre
2013-06-01
Ocean acidification represents a threat to marine species worldwide, and forecasting the ecological impacts of acidification is a high priority for science, management, and policy. As research on the topic expands at an exponential rate, a comprehensive understanding of the variability in organisms' responses and corresponding levels of certainty is necessary to forecast the ecological effects. Here, we perform the most comprehensive meta-analysis to date by synthesizing the results of 228 studies examining biological responses to ocean acidification. The results reveal decreased survival, calcification, growth, development and abundance in response to acidification when the broad range of marine organisms is pooled together. However, the magnitude of these responses varies among taxonomic groups, suggesting there is some predictable trait-based variation in sensitivity, despite the investigation of approximately 100 new species in recent research. The results also reveal an enhanced sensitivity of mollusk larvae, but suggest that an enhanced sensitivity of early life history stages is not universal across all taxonomic groups. In addition, the variability in species' responses is enhanced when they are exposed to acidification in multi-species assemblages, suggesting that it is important to consider indirect effects and exercise caution when forecasting abundance patterns from single-species laboratory experiments. Furthermore, the results suggest that other factors, such as nutritional status or source population, could cause substantial variation in organisms' responses. Last, the results highlight a trend towards enhanced sensitivity to acidification when taxa are concurrently exposed to elevated seawater temperature. © 2013 Blackwell Publishing Ltd.
Corrado, C; Santarelli, M T; Pavlovsky, S; Pizzolato, M
1989-12-01
Four hundred ten previously untreated multiple myeloma patients entered onto two consecutive Grupo Argentino de Tratamiento de la Leucemia Aguda (GATLA) protocols were analyzed to identify significant prognostic factors influencing survival. The univariate analysis selected the following variables: performance status, renal function, percentage of bone marrow plasma cells at diagnosis, hemoglobin, and age. A multivariate analysis showed that performance status, renal function, percentage of bone marrow plasma cells, hemoglobin, and age were the best predictive variables for survival. A score was assigned to each patient according to these variables, which led to their classification in three groups: good, intermediate, and poor risk, with a probability of survival of 26% and 10% at 96 months, and 5% at 56 months, and median survival of 60, 37, and 14 months, respectively (P = .0000). In our patient population, this model proved to be superior to the Durie-Salmon staging system in defining prognostic risk groups, and separating patients with significantly different risks within each Durie-Salmon stage.
Brosschot, Jos F; Verkuil, Bart; Thayer, Julian F
2016-06-01
From a combined neurobiological and evolution-theoretical perspective, the stress response is a subcortically subserved response to uncertainty that is not 'generated' but 'default': the stress response is 'always there' but as long as safety is perceived, the stress response is under tonic prefrontal inhibition, reflected by high vagally mediated heart rate variability. Uncertainty of safety leads to disinhibiting the default stress response, even in the absence of threat. Due to the stress response's survival value, this 'erring on the side of caution' is passed to us via our genes. Thus, intolerance of uncertainty is not acquired during the life cycle, but is a given property of all living organisms, only to be alleviated in situations of which the safety is learned. When the latter is deficient, generalized unsafety ensues, which underlies chronic anxiety and stress and their somatic health risks, as well as other highly prevalent conditions carrying such risks, including loneliness, obesity, aerobic unfitness and old age. Copyright © 2016 Elsevier Ltd. All rights reserved.
Comorbidity and prognosis in advanced hypopharyngeal-laryngeal cancer under combined therapy.
Montero, Elena Hernández; Trufero, Javier Martínez; Romeo, Javier Azúa; Terré, Fernando Clau
2008-01-01
The success of combined treatment in head and neck cancer resides largely in its completion, which can be compromised when the patient's general health status is precarious. The objective of this investigation was to study the role of comorbidity as a prognostic factor in a large, homogeneous population affected by locally advanced pharyngeal-laryngeal cancer, under a combined protocol treatment. The a priori hypothesis is that comorbidity strongly conditions overall survival and specific overall survival in these patients and can aid in the selection and individualization of treatments. After a 24-month follow-up, a univariate and multivariate retrospective analysis of survival and prognostic factors was performed using 14 clinical, pathological and molecular variables including the comorbidity index calculated following the Picarillo method. The settings were the Otolaryngology, Oncology and Pathology Departments of the Miguel Servet University Hospital, Zaragoza, Spain, a referral center of the National Health System. Of the original 114 patients selected, 15 were withdrawn because the tumor spread to maxillofacial areas, or due to the lack of attendance at the clinic, incomplete clinical data or coexistent primary tumors. The group under analysis consisted of the 99 remaining patients affected by stage III and IV laryngeal and/or hypopharyngeal cancers that had not received previous treatments. The main outcomes to analyze were overall survival, specific overall survival and relative risk. Overall survival at 2.5 years was 68.1% (95% CI, 57.7-78.5). Specific overall survival at 2.5 years was 74.8% (95% CI, 64.9-84.6). In the multivariate analysis, tumor staging, neoadjuvant chemotherapy response and comorbidity (RR = 1.55 and 1.44 for overall and specific overall survival, respectively) present themselves as three prognostic factors independent of overall and specific overall survival. The role of comorbidity as an independent prognostic factor in patients affected by laryngeal and/or hypopharyngeal cancer treated with chemo-radiotherapy should be taken into account in the tailoring of treatments and the improvement of therapeutic results.
Knollmann, Friedrich D; Kumthekar, Rohan; Fetzer, David; Socinski, Mark A
2014-03-01
We set out to investigate whether volumetric tumor measurements allow for a prediction of treatment response, as measured by patient survival, in patients with advanced non-small-cell lung cancer (NSCLC). Patients with nonresectable NSCLC (stage III or IV, n = 100) who were repeatedly evaluated for treatment response by computed tomography (CT) were included in a Health Insurance Portability and Accountability Act (HIPAA)-compliant retrospective study. Tumor response was measured by comparing tumor volumes over time. Patient survival was compared with Response Evaluation Criteria in Solid Tumors (RECIST) using Kaplan-Meier survival statistics and Cox regression analysis. The median overall patient survival was 553 days (standard error, 146 days); for patients with stage III NSCLC, it was 822 days, and for patients with stage IV disease, 479 days. The survival differences were not statistically significant (P = .09). According to RECIST, 5 patients demonstrated complete response, 39 partial response, 44 stable disease, and 12 progressive disease. Patient survival was not significantly associated with RECIST class, the change of the sum of tumor diameters (P = .98), nor the change of the sum of volumetric tumor dimensions (P = .17). In a group of 100 patients with advanced-stage NSCLC, neither volumetric CT measurements of changes in tumor size nor RECIST class significantly predicted patient survival. This observation suggests that size response may not be a sufficiently precise surrogate marker of success to steer treatment decisions in individual patients. Copyright © 2014 Elsevier Inc. All rights reserved.
Effects of weather on survival in populations of boreal toads in Colorado
Scherer, R. D.; Muths, E.; Lambert, B.A.
2008-01-01
Understanding the relationships between animal population demography and the abiotic and biotic elements of the environments in which they live is a central objective in population ecology. For example, correlations between weather variables and the probability of survival in populations of temperate zone amphibians may be broadly applicable to several species if such correlations can be validated for multiple situations. This study focuses on the probability of survival and evaluates hypotheses based on six weather variables in three populations of Boreal Toads (Bufo boreas) from central Colorado over eight years. In addition to suggesting a relationship between some weather variables and survival probability in Boreal Toad populations, this study uses robust methods and highlights the need for demographic estimates that are precise and have minimal bias. Capture-recapture methods were used to collect the data, and the Cormack-Jolly-Seber model in program MARK was used for analysis. The top models included minimum daily winter air temperature, and the sum of the model weights for these models was 0.956. Weaker support was found for the importance of snow depth and the amount of environmental moisture in winter in modeling survival probability. Minimum daily winter air temperature was positively correlated with the probability of survival in Boreal Toads at other sites in Colorado and has been identified as an important covariate in studies in other parts of the world. If air temperatures are an important component of survival for Boreal Toads or other amphibians, changes in climate may have profound impacts on populations. Copyright 2008 Society for the Study of Amphibians and Reptiles.
Pedro, Brigite M; Alves, Joana V; Cripps, Peter J; Stafford Johnson, Mike J; Martin, Mike W S
2011-12-01
The purpose of this study was to investigate the prognostic value of QRS duration in dogs with dilated cardiomyopathy (DCM) by studying its relationship with survival time. The medical records of dogs diagnosed with DCM were retrospectively searched for good quality ECG tracings. The QRS duration was measured from the ECG tracing and two different models were used: binary variable (dogs were divided into 2 groups based on a QRS duration of <60 ms or ≥60 ms) and continuous variable. The survival times were analysed by the Kaplan-Meier method and Cox's proportional hazard model. 266 dogs met the inclusion and exclusion criteria. A QRS duration ≥60 ms was associated with a reduced survival time compared to those with a QRS duration <60 ms (Hazard Ratio of 1.34, 95% CI 1.05-1.71, P = 0.02). When considered as a continuous variable the Hazard Ratio was 1.015 for each increase in QRS duration of 1 ms (95% CI 1.006-1.024, p = 0.001).Dogs with a QRS duration < 60 ms had a median survival time (IQ range) of 25 weeks (97-65) and dogs with a QRS duration ≥60 ms had a median survival time (IQ range) of 13 weeks (3-34). The measurement of QRS duration is relatively simple to perform from a surface ECG recording. A duration ≥60 ms is associated with shorter survival times in dogs with DCM, which may provide practitioners with additional prognostic information. Copyright © 2011 Elsevier B.V. All rights reserved.
Moses, Martin R; Frey, Jennifer K; Roemer, Gary W
2012-01-01
Modest increases in global temperature have been implicated in causing population extirpations and range shifts in taxa inhabiting colder environs and in ectotherms whose thermoregulation is more closely tied to environmental conditions. Many arid-adapted endotherms already experience conditions at their physiological limits, so it is conceivable that they could be similarly affected by warming temperatures. We explored how climatic variables might influence the apparent survival of the banner-tailed kangaroo rat (Dipodomys spectabilis), a rodent endemic to the Chihuahuan Desert of North America and renowned for its behavioral and physiological adaptations to arid environments. Relative variable weight, strength of variable relationships, and other criteria indicated that summer, diurnal land surface temperature (SD_LST) was the primary environmental driver of apparent survival in these arid-adapted rodents. Higher temperatures had a negative effect on apparent survival, which ranged from 0.15 (SE = 0.04) for subadults to 0.50 (SE = 0.07) for adults. Elevated SD_LST may negatively influence survival through multiple pathways, including increased water loss and energy expenditure that could lead to chronic stress and/or hyperthermia that could cause direct mortality. Land surface temperatures are predicted to increase by as much 6.5°C by 2099, reducing apparent survival of adults to ~0.15 in some regions of the species' range, possibly causing a shift in their distribution. The relationship between SD_LST and survival suggests a mechanism whereby physiological tolerances are exceeded resulting in a reduction to individual fitness that may ultimately cause a shift in the species' range over time.
Teo, Min Yuen; Bambury, Richard M; Zabor, Emily C; Jordan, Emmet; Al-Ahmadie, Hikmat; Boyd, Mariel E; Bouvier, Nancy; Mullane, Stephanie A; Cha, Eugene K; Roper, Nitin; Ostrovnaya, Irina; Hyman, David M; Bochner, Bernard H; Arcila, Maria E; Solit, David B; Berger, Michael F; Bajorin, Dean F; Bellmunt, Joaquim; Iyer, Gopakumar; Rosenberg, Jonathan E
2017-07-15
Purpose: Platinum-based chemotherapy remains the standard treatment for advanced urothelial carcinoma by inducing DNA damage. We hypothesize that somatic alterations in DNA damage response and repair (DDR) genes are associated with improved sensitivity to platinum-based chemotherapy. Experimental Design: Patients with diagnosis of locally advanced and metastatic urothelial carcinoma treated with platinum-based chemotherapy who had exon sequencing with the Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT) assay were identified. Patients were dichotomized based on the presence/absence of alterations in a panel of 34 DDR genes. DDR alteration status was correlated with clinical outcomes and disease features. Results: One hundred patients were identified, of which 47 harbored alterations in DDR genes. Patients with DDR alterations had improved progression-free survival (9.3 vs. 6.0 months, log-rank P = 0.007) and overall survival (23.7 vs. 13.0 months, log-rank P = 0.006). DDR alterations were also associated with higher number mutations and copy-number alterations. A trend toward positive correlation between DDR status and nodal metastases and inverse correlation with visceral metastases were observed. Different DDR pathways also suggested variable impact on clinical outcomes. Conclusions: Somatic DDR alteration is associated with improved clinical outcomes in platinum-treated patients with advanced urothelial carcinoma. Once validated, it can improve patient selection for clinical practice and future study enrollment. Clin Cancer Res; 23(14); 3610-8. ©2017 AACR . ©2017 American Association for Cancer Research.
Amato, Eliana; Fassan, Matteo; Novello, Silvia; Peretti, Umberto; Vavalà, Tiziana; Kinspergher, Stefania; Righi, Luisella; Santo, Antonio; Brunelli, Matteo; Corbo, Vincenzo; Giglioli, Eliana; Sperduti, Isabella; Milella, Michele; Chilosi, Marco; Scarpa, Aldo; Tortora, Giampaolo
2015-01-01
Cancer molecular heterogeneity might explain the variable response of EGFR mutant lung adenocarcinomas to tyrosine kinase inhibitors (TKIs). We assessed the mutational status of 22 cancer genes by next-generation sequencing (NGS) in poor, intermediate or good responders to first-line gefitinib. Clinical outcome was correlated with Additional Coexisting Mutations (ACMs) and the EGFR Proportion of Mutated Alleles (PMA). Thirteen ACMs were found in 10/17 patients: TP53 (n=6), KRAS (n=2), CTNNB1 (n=2), PIK3CA, SMAD4 and MET (n=1 each). TP53 mutations were exclusive of poor/intermediate responders (66.7% versus 0, p=0.009). Presence of ACMs significantly affected both PFS (median 3.0 versus 12.3 months, p=0.03) and survival (3.6 months versus not reached, p=0.03). TP53 mutation was the strongest negative modifier (median PFS 4.0 versus 14.0 months). Higher EGFR PMA was present in good versus poor/intermediate responders. Median PFS and survival were longer in patients with EGFR PMA ≥0.36 (12.0 versus 4.0 months, p=0.31; not reached versus 18.0 months, p=0.59). Patients with an EGFR PMA ≥0.36 and no ACMs fared significantly better (p=0.03), with a trend towards increased survival (p=0.06). Our exploratory data suggest that a quantitative (PMA) and qualitative (ACMs) molecular heterogeneity assessment using NGS might be useful for a better selection of patients. PMID:25904052
Survival curve estimation with dependent left truncated data using Cox's model.
Mackenzie, Todd
2012-10-19
The Kaplan-Meier and closely related Lynden-Bell estimators are used to provide nonparametric estimation of the distribution of a left-truncated random variable. These estimators assume that the left-truncation variable is independent of the time-to-event. This paper proposes a semiparametric method for estimating the marginal distribution of the time-to-event that does not require independence. It models the conditional distribution of the time-to-event given the truncation variable using Cox's model for left truncated data, and uses inverse probability weighting. We report the results of simulations and illustrate the method using a survival study.
Dying like rabbits: general determinants of spatio-temporal variability in survival.
Tablado, Zulima; Revilla, Eloy; Palomares, Francisco
2012-01-01
1. Identifying general patterns of how and why survival rates vary across space and time is necessary to truly understand population dynamics of a species. However, this is not an easy task given the complexity and interactions of processes involved, and the interpopulation differences in main survival determinants. 2. Here, using European rabbits (Oryctolagus cuniculus) as a model and information from local studies, we investigated whether we could make inferences about trends and drivers of survival of a species that are generalizable to large spatio-temporal scales. To do this, we first focused on overall survival and then examined cause-specific mortalities, mainly predation and diseases, which may lead to those patterns. 3. Our results show that within the large-scale variability in rabbit survival, there exist general patterns that are explained by the integration of factors previously known to be important at the local level (i.e. age, climate, diseases, predation or density dependence). We found that both inter- and intrastudy survival rates increased in magnitude and decreased in variability as rabbits grow old, although this tendency was less pronounced in populations with epidemic diseases. Some causes leading to these higher mortalities in young rabbits could be the stronger effect of rainfall at those ages, as well as, other death sources like malnutrition or infanticide. 4. Predation is also greater for newborns and juveniles, especially in population without diseases. Apart from the effect of diseases, predation patterns also depended on factors, such as, density, season, and type and density of predators. Finally, we observed that infectious diseases also showed general relationships with climate, breeding (i.e. new susceptible rabbits) and age, although the association type varied between myxomatosis and rabbit haemorrhagic disease. 5. In conclusion, large-scale patterns of spatio-temporal variability in rabbit survival emerge from the combination of different factors that interrelate both directly and through density dependence. This highlights the importance of performing more comprehensive studies to reveal combined effects and complex relationships that help us to better understand the mechanisms underlying population dynamics. © 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society.
Racial disparity in colorectal cancer: the role of equal treatment.
Laryea, Jonathan A; Siegel, Eric; Klimberg, Suzanne
2014-03-01
Racial disparity exists in colorectal cancer outcomes. The reasons for this are multifactorial. The aim of this study was to evaluate the role of equal treatment of blacks and whites in the elimination of racial disparity in colorectal cancer outcomes. A retrospective cohort study of 878 patients with colorectal cancer diagnosed between 1998 and 2008 was done at a University tertiary referral center. Demographic variables including age, sex, and race were abstracted. Tumor-specific variables including American Joint Committee on Cancer stage, anatomic tumor location, vital status, and survival were obtained. Treatment-specific variables including surgery, chemotherapy, radiotherapy, and follow-up were also obtained. Racial differences in these variables were studied and their effect on overall survival was determined by using univariate and multivariate analyses. The findings were then compared with previous data from our institution. University tertiary referral center. The primary outcomes measured were overall survival and cancer-specific mortality. A total of 878 patients met the inclusion criteria, 186 (21.2%) of whom were black. Blacks were significantly younger at diagnosis in comparison with whites, with a median (quartiles) age of 55 years (28-87) compared with 59 years (23-94) (p = 0.0012). Equal proportions of blacks (78.5%) and whites (79.2%) underwent surgery (p = 0.84), similar proportions of blacks (55.4%) and whites (60.8%) received chemotherapy (p = 0.18), and similar proportions of blacks (17.2%) and whites (20.5%) received radiation therapy (p = 0.31). There was no difference in overall survival or cancer-specific mortality between the 2 racial groups. Univariate analysis showed American Joint Committee on Cancer stage and surgery as the only statistically significant factors for overall survival. On multivariate analysis, stage, surgery, and chemotherapy were the only statistically significant factors. Race was not an independent determinant of survival. There were no differences in overall survival and cancer-related mortality between blacks and whites, and this may have resulted from identical treatment. The previously noted disparities in treatment and overall survival at our institution have disappeared.
Abdullah, Wan Zawiah Wan; Mackey, Bernard M; Karatzas, Kimon Andreas G
2018-01-01
Salmonella is an important foodborne pathogen, whose ability to resist stress and survive can vary among strains. This variability is normally not taken into account when predictions are made about survival in foods with negative consequences. Therefore, we examined the contribution of variable phenotypic properties to survival under stress in 10 Salmonella serovars. One strain (Typhimurium 10) was intentionally RpoS-negative; however, another strain (Heidelberg) showed an rpoS mutation, rendering it inactive. We assessed an array of characteristics (motility, biofilm formation, bile resistance, acid resistance, and colony morphology) that show major variability among strains associated with a 10- to 19-fold difference between the highest and the lowest strain for most characteristics. The RpoS status of isolates did not affect variability in the characteristics, with the exception of resistance to NaCl, acetic acid, lactic acid, and the combination of acetic acid and salt, where the variability between the highest and the lowest strain was reduced to 3.1-fold, 1.7-fold, 2-fold, and 1.7-fold, respectively, showing that variability was significant among RpoS-positive strains. Furthermore, we also found a good correlation between acid resistance and lysine decarboxylase activity, showing its importance for acid resistance, and demonstrated a possible role of RpoS in the lysine decarboxylase activity in Salmonella.
Ozgul, Arpat; Armitage, Kenneth B; Blumstein, Daniel T; Oli, Madan K
2006-04-01
Spatiotemporal variation in age-specific survival rates can profoundly influence population dynamics, but few studies of vertebrates have thoroughly investigated both spatial and temporal variability in age-specific survival rates. We used 28 years (1976-2003) of capture-mark-recapture (CMR) data from 17 locations to parameterize an age-structured Cormack-Jolly-Seber model, and investigated spatial and temporal variation in age-specific annual survival rates of yellow-bellied marmots (Marmota flaviventris). Survival rates varied both spatially and temporally, with survival of younger animals exhibiting the highest degree of variation. Juvenile survival rates varied from 0.52 +/- 0.05 to 0.78 +/- 0.10 among sites and from 0.15 +/- 0.14 to 0.89 +/- 0.06 over time. Adult survival rates varied from 0.62 +/- 0.09 to 0.80 +/- 0.03 among sites, but did not vary significantly over time. We used reverse-time CMR models to estimate the realized population growth rate (lamda), and to investigate the influence of the observed variation in age-specific survival rates on lamda. The realized growth rate of the population closely covaried with, and was significantly influenced by, spatiotemporal variation in juvenile survival rate. High variability in juvenile survival rates over space and time clearly influenced the dynamics of our study population and is also likely to be an important determinant of the spatiotemporal variation in the population dynamics of other mammals with similar life history characteristics.
Complex life cycles and the responses of insects to climate change.
Kingsolver, Joel G; Woods, H Arthur; Buckley, Lauren B; Potter, Kristen A; MacLean, Heidi J; Higgins, Jessica K
2011-11-01
Many organisms have complex life cycles with distinct life stages that experience different environmental conditions. How does the complexity of life cycles affect the ecological and evolutionary responses of organisms to climate change? We address this question by exploring several recent case studies and synthetic analyses of insects. First, different life stages may inhabit different microhabitats, and may differ in their thermal sensitivities and other traits that are important for responses to climate. For example, the life stages of Manduca experience different patterns of thermal and hydric variability, and differ in tolerance to high temperatures. Second, life stages may differ in their mechanisms for adaptation to local climatic conditions. For example, in Colias, larvae in different geographic populations and species adapt to local climate via differences in optimal and maximal temperatures for feeding and growth, whereas adults adapt via differences in melanin of the wings and in other morphological traits. Third, we extend a recent analysis of the temperature-dependence of insect population growth to demonstrate how changes in temperature can differently impact juvenile survival and adult reproduction. In both temperate and tropical regions, high rates of adult reproduction in a given environment may not be realized if occasional, high temperatures prevent survival to maturity. This suggests that considering the differing responses of multiple life stages is essential to understand the ecological and evolutionary consequences of climate change. © The Author 2011. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved.
Ibrutinib as Initial Therapy for Patients with Chronic Lymphocytic Leukemia
Burger, Jan A.; Tedeschi, Alessandra; Barr, Paul M.; Robak, Tadeusz; Owen, Carolyn; Ghia, Paolo; Bairey, Osnat; Hillmen, Peter; Bartlett, Nancy L.; Li, Jianyong; Simpson, David; Grosicki, Sebastian; Devereux, Stephen; McCarthy, Helen; Coutre, Steven; Quach, Hang; Gaidano, Gianluca; Maslyak, Zvenyslava; Stevens, Don A.; Janssens, Ann; Offner, Fritz; Mayer, Jiří; O'Dwyer, Michael; Hellmann, Andrzej; Schuh, Anna; Siddiqi, Tanya; Polliack, Aaron; Tam, Constantine S.; Suri, Deepali; Cheng, Mei; Clow, Fong; Styles, Lori; James, Danelle F.; Kipps, Thomas J.
2016-01-01
BACKGROUND Chronic lymphocytic leukemia (CLL) primarily affects older persons who often have coexisting conditions in addition to disease-related immunosuppression and myelosuppression. We conducted an international, open-label, randomized phase 3 trial to compare two oral agents, ibrutinib and chlorambucil, in previously untreated older patients with CLL or small lymphocytic lymphoma. METHODS We randomly assigned 269 previously untreated patients who were 65 years of age or older and had CLL or small lymphocytic lymphoma to receive ibrutinib or chlorambucil. The primary end point was progression-free survival as assessed by an independent review committee. RESULTS The median age of the patients was 73 years. During a median follow-up period of 18.4 months, ibrutinib resulted in significantly longer progression-free survival than did chlorambucil (median, not reached vs. 18.9 months), with a risk of progression or death that was 84% lower with ibrutinib than that with chlorambucil (hazard ratio, 0.16; P<0.001). Ibrutinib significantly prolonged overall survival; the estimated survival rate at 24 months was 98% with ibrutinib versus 85% with chlorambucil, with a relative risk of death that was 84% lower in the ibrutinib group than in the chlorambucil group (hazard ratio, 0.16; P=0.001). The overall response rate was higher with ibrutinib than with chlorambucil (86% vs. 35%, P<0.001). The rates of sustained increases from baseline values in the hemoglobin and platelet levels were higher with ibrutinib. Adverse events of any grade that occurred in at least 20% of the patients receiving ibrutinib included diarrhea, fatigue, cough, and nausea; adverse events occurring in at least 20% of those receiving chlorambucil included nausea, fatigue, neutropenia, anemia, and vomiting. In the ibrutinib group, four patients had a grade 3 hemorrhage and one had a grade 4 hemorrhage. A total of 87% of the patients in the ibrutinib group are continuing to take ibrutinib. CONCLUSIONS Ibrutinib was superior to chlorambucil in previously untreated patients with CLL or small lymphocytic lymphoma, as assessed by progression-free survival, overall survival, response rate, and improvement in hematologic variables. (Funded by Pharmacyclics and others; RESONATE-2 ClinicalTrials.gov number, NCT01722487.) PMID:26639149
DOE Office of Scientific and Technical Information (OSTI.GOV)
Riley, Joseph, M., Jr.; Jones, Robert, H.
2003-01-01
Riley, J.M. Jr., and R.H.Jones. 2003. Factors limiting regeneration of Quercus alba and Cornus florida in formerly cultivated coastal plain sites, South Carolina. For. Ecol., and Mgt. 177:571-586. To determine the extent that resources, conditions, and herbivoryy limit regeneration of Quercus alba L. and Cornus florida L. in formerly cultivated coastal plain uplands, we planted seedlings of the two species in two pine and one pine-hardwood forest understory and three adjacent clearcuts. Soil carbon and moisture, available nitrogen and phosphorous, and gap light index (GLI) were measured next to each seedling. Over two growing seasons, stem and leaf herbivory weremore » estimated and survival was recorded. At the end of 2 years, all surviving stems were harvested to determine total leaf area and 2-year biomass growth. Survival to the end of the study was not significantly different between clearcuts and understories. However, clearcuts led to significantly greater biomass growth and leaf area for both Q. alba and C. florida. Soil moisture and available nutrients were also greater in the clearcuts. Using separate multiple linear (growth) or logistic (survival) regressions for each combination of three sites, two cutting treatments and two species, we found that soil moisture significantly affected survival in 12.5% and biomass growth in 8.3% of the regressions. Light availability significantly impacted biomass growth in 16.7% of the regressions. Stem and leaf herbivory had very little impact on survival (8.3%), but when combined, these two factors significantly impacted leaf area or biomass growth in 33.3% of the regressions. Seedling responses were highly variable, and no regression model accounted for more that 70.0% of this variation. In our study, stand-scalevariation in seedling responses (especially the difference between clearcut and understory) was much greater than within-stand variation. Of the within stand factors measured, herbivory was clearly the most important. To establish these species in mesic upland coastal plain sites, we recommend planting immediately after clearcutting.« less
Ibrutinib as Initial Therapy for Patients with Chronic Lymphocytic Leukemia.
Burger, Jan A; Tedeschi, Alessandra; Barr, Paul M; Robak, Tadeusz; Owen, Carolyn; Ghia, Paolo; Bairey, Osnat; Hillmen, Peter; Bartlett, Nancy L; Li, Jianyong; Simpson, David; Grosicki, Sebastian; Devereux, Stephen; McCarthy, Helen; Coutre, Steven; Quach, Hang; Gaidano, Gianluca; Maslyak, Zvenyslava; Stevens, Don A; Janssens, Ann; Offner, Fritz; Mayer, Jiří; O'Dwyer, Michael; Hellmann, Andrzej; Schuh, Anna; Siddiqi, Tanya; Polliack, Aaron; Tam, Constantine S; Suri, Deepali; Cheng, Mei; Clow, Fong; Styles, Lori; James, Danelle F; Kipps, Thomas J
2015-12-17
Chronic lymphocytic leukemia (CLL) primarily affects older persons who often have coexisting conditions in addition to disease-related immunosuppression and myelosuppression. We conducted an international, open-label, randomized phase 3 trial to compare two oral agents, ibrutinib and chlorambucil, in previously untreated older patients with CLL or small lymphocytic lymphoma. We randomly assigned 269 previously untreated patients who were 65 years of age or older and had CLL or small lymphocytic lymphoma to receive ibrutinib or chlorambucil. The primary end point was progression-free survival as assessed by an independent review committee. The median age of the patients was 73 years. During a median follow-up period of 18.4 months, ibrutinib resulted in significantly longer progression-free survival than did chlorambucil (median, not reached vs. 18.9 months), with a risk of progression or death that was 84% lower with ibrutinib than that with chlorambucil (hazard ratio, 0.16; P<0.001). Ibrutinib significantly prolonged overall survival; the estimated survival rate at 24 months was 98% with ibrutinib versus 85% with chlorambucil, with a relative risk of death that was 84% lower in the ibrutinib group than in the chlorambucil group (hazard ratio, 0.16; P=0.001). The overall response rate was higher with ibrutinib than with chlorambucil (86% vs. 35%, P<0.001). The rates of sustained increases from baseline values in the hemoglobin and platelet levels were higher with ibrutinib. Adverse events of any grade that occurred in at least 20% of the patients receiving ibrutinib included diarrhea, fatigue, cough, and nausea; adverse events occurring in at least 20% of those receiving chlorambucil included nausea, fatigue, neutropenia, anemia, and vomiting. In the ibrutinib group, four patients had a grade 3 hemorrhage and one had a grade 4 hemorrhage. A total of 87% of the patients in the ibrutinib group are continuing to take ibrutinib. Ibrutinib was superior to chlorambucil in previously untreated patients with CLL or small lymphocytic lymphoma, as assessed by progression-free survival, overall survival, response rate, and improvement in hematologic variables. (Funded by Pharmacyclics and others; RESONATE-2 ClinicalTrials.gov number, NCT01722487.).
Johnsen, Bjørn Helge; Hansen, Anita L; Murison, Robert; Eid, Jarle; Thayer, Julian F
2012-01-01
The aim of the paper was to study the relationship between heart rate variability (HRV) and cortisol release during cognitive challenging tasks. Forty-nine male naval cadets from the Royal Norwegian Naval Academy were administered computerised versions of attentional and working memory tests. The results from this study support the hypothesis of a negative correlation between HRV and cortisol secretion during cognitive tasks. Confirmation of the hypothesis with the low HRV group scoring higher on cortisol only during performance of cognitive tasks and recovery was also found. Furthermore, a replication of the previous findings of a negative association between cortisol levels and performance were supported when using uncorrected comparisons. None of the correlations survived Bonferonin corrections. The findings are discussed in relation to factors increasing HRV, thus improving tolerance to cognitive stress in onboard environments.
Implications of genome-wide association studies in cancer therapeutics.
Patel, Jai N; McLeod, Howard L; Innocenti, Federico
2013-09-01
Genome wide association studies (GWAS) provide an agnostic approach to identifying potential genetic variants associated with disease susceptibility, prognosis of survival and/or predictive of drug response. Although these techniques are costly and interpretation of study results is challenging, they do allow for a more unbiased interrogation of the entire genome, resulting in the discovery of novel genes and understanding of novel biological associations. This review will focus on the implications of GWAS in cancer therapy, in particular germ-line mutations, including findings from major GWAS which have identified predictive genetic loci for clinical outcome and/or toxicity. Lessons and challenges in cancer GWAS are also discussed, including the need for functional analysis and replication, as well as future perspectives for biological and clinical utility. Given the large heterogeneity in response to cancer therapeutics, novel methods of identifying mechanisms and biology of variable drug response and ultimately treatment individualization will be indispensable. © 2013 The British Pharmacological Society.
Brain connectivity reflects human aesthetic responses to music
Sachs, Matthew E.; Ellis, Robert J.; Schlaug, Gottfried
2016-01-01
Abstract Humans uniquely appreciate aesthetics, experiencing pleasurable responses to complex stimuli that confer no clear intrinsic value for survival. However, substantial variability exists in the frequency and specificity of aesthetic responses. While pleasure from aesthetics is attributed to the neural circuitry for reward, what accounts for individual differences in aesthetic reward sensitivity remains unclear. Using a combination of survey data, behavioral and psychophysiological measures and diffusion tensor imaging, we found that white matter connectivity between sensory processing areas in the superior temporal gyrus and emotional and social processing areas in the insula and medial prefrontal cortex explains individual differences in reward sensitivity to music. Our findings provide the first evidence for a neural basis of individual differences in sensory access to the reward system, and suggest that social–emotional communication through the auditory channel may offer an evolutionary basis for music making as an aesthetically rewarding function in humans. PMID:26966157
Holmgren, Milena; Gómez-Aparicio, Lorena; Quero, José Luis; Valladares, Fernando
2012-06-01
The combined effects of shade and drought on plant performance and the implications for species interactions are highly debated in plant ecology. Empirical evidence for positive and negative effects of shade on the performance of plants under dry conditions supports two contrasting theoretical models about the role of shade under dry conditions: the trade-off and the facilitation hypotheses. We performed a meta-analysis of field and greenhouse studies evaluating the effects of drought at two or more irradiance levels on nine response variables describing plant physiological condition, growth, and survival. We explored differences in plant response across plant functional types, ecosystem types and methodological approaches. The data were best fit using quadratic models indicating a humped-back shape response to drought along an irradiance gradient for survival, whole plant biomass, maximum photosynthetic capacity, stomatal conductance and maximal photochemical efficiency. Drought effects were ameliorated at intermediate irradiance, becoming more severe at higher or lower light levels. This general pattern was maintained when controlling for potential variations in the strength of the drought treatment among light levels. Our quantitative meta-analysis indicates that dense shade ameliorates drought especially among drought-intolerant and shade-tolerant species. Wet tropical species showed larger negative effects of drought with increasing irradiance than semiarid and cold temperate species. Non-linear responses to irradiance were stronger under field conditions than under controlled greenhouse conditions. Non-linear responses to drought along the irradiance gradient reconciliate opposing views in plant ecology, indicating that facilitation is more likely within certain range of environmental conditions, fading under deep shade, especially for drought-tolerant species.
Carceller, Fernando; Bautista, Francisco J; Fowkes, Lucy A; Marshall, Lynley V; Sirvent, Sara I; Chisholm, Julia C; Pearson, Andrew D J; Koh, Dow-Mu; Moreno, Lucas
2016-08-01
RECIST guidelines constitute the reference for radiological response assessment in most paediatric trials of anticancer agents. However, these criteria have not been validated in children. We evaluated the outcomes and patterns of progression of children/adolescents enrolled in phase I trials in two paediatric drug development units. Patients aged ≤21 assessed with RECIST (v1.0 or v1.1) were eligible. Clinico-radiological data were analysed using Mann-Whitney U and log-rank tests to correlate response categories and sum of longest diameters (SLD) with time-to-event variables and overall survival (OS). Sixty-one patients (71 enrolments) were evaluated; median age: 12.7 years (range, 3.1-20.9). Overall, 7% achieved complete/partial response (n = 5) and 31% disease stabilisation (n = 22). Median (95% CI) OS (in months) was 29.1 (27.6-30.6) with complete/partial response, 8.9 (2.0-15.8) with stable disease and 2.8 (2.3-3.3) with disease progression (P < 0.001); 32.6% patients with measurable disease presented exclusive progression of existing non-target lesions and/or new lesions. The change in SLD at best response showed a linear correlation with duration of response (r = -0.605; P = 0.004) and time on trial (r = -0.61; P = 0.003), but the change in SLD at progression did not correlate with time to progression (r = -0.219; P = 0.206). Response assessment according to RECIST correlated with OS in children/adolescents treated on phase I trials. The reduction in SLD at best response correlated with more prolonged responses. Tumour size did not constitute an optimal method to assess disease progression in one third of patients with measurable disease. Further refinement of current response assessment guidelines will enable the development of paediatric-specific radiological criteria. © 2016 Wiley Periodicals, Inc.
Hastings, Kelly K; Jemison, Lauri A; Pendleton, Grey W
2018-01-01
Population dynamics of long-lived vertebrates depend critically on adult survival, yet factors affecting survival and covariation between survival and other vital rates in adults remain poorly examined for many taxonomic groups of long-lived mammals (e.g. actuarial senescence has been examined for only 9 of 34 extant pinniped species using longitudinal data). We used mark-recapture models and data from 2795 Steller sea lion ( Eumetopias jubatus ) pups individually marked at four of five rookeries in southeastern Alaska (SEAK) and resighted for 21 years to examine senescence, annual variability and covariation among life-history traits in this long-lived, sexually dimorphic pinniped. Sexes differed in age of onset (approx. 16-17 and approx. 8-9 years for females and males, respectively), but not rate (-0.047 and -0.046/year of age for females and males) of senescence. Survival of adult males from northern SEAK had greatest annual variability (approx. ±0.30 among years), whereas survival of adult females ranged approximately ±0.10 annually. Positive covariation between male survival and reproductive success was observed. Survival of territorial males was 0.20 higher than that of non-territorial males, resulting in the majority of males alive at oldest ages being territorial.
Jemison, Lauri A.; Pendleton, Grey W.
2018-01-01
Population dynamics of long-lived vertebrates depend critically on adult survival, yet factors affecting survival and covariation between survival and other vital rates in adults remain poorly examined for many taxonomic groups of long-lived mammals (e.g. actuarial senescence has been examined for only 9 of 34 extant pinniped species using longitudinal data). We used mark–recapture models and data from 2795 Steller sea lion (Eumetopias jubatus) pups individually marked at four of five rookeries in southeastern Alaska (SEAK) and resighted for 21 years to examine senescence, annual variability and covariation among life-history traits in this long-lived, sexually dimorphic pinniped. Sexes differed in age of onset (approx. 16–17 and approx. 8–9 years for females and males, respectively), but not rate (−0.047 and −0.046/year of age for females and males) of senescence. Survival of adult males from northern SEAK had greatest annual variability (approx. ±0.30 among years), whereas survival of adult females ranged approximately ±0.10 annually. Positive covariation between male survival and reproductive success was observed. Survival of territorial males was 0.20 higher than that of non-territorial males, resulting in the majority of males alive at oldest ages being territorial. PMID:29410794
Milner, Rowan J; Peyton, Jamie; Cooke, Kirsten; Fox, Leslie E; Gallagher, Alexander; Gordon, Patti; Hester, Juli
2005-10-01
To determine response rates and survival times for cats with lymphoma treated with the University of Wisconsin-Madison chemotherapy protocol. Retrospective study. 38 cats with lymphoma. Medical records were reviewed, and information on age, sex, breed, FeLV and FIV infection status, anatomic form, clinical stage, and survival time was obtained. Immunophenotyping was not performed. Mean +/- SD age of the cats was 10.9 +/- 4.4 years. Overall median survival time was 210 days (interquartile range, 90 to 657 days), and overall duration of first remission was 156 days (interquartile range, 87 to 316 days). Age, sex, anatomic form, and clinical stage were not significantly associated with duration of first remission or survival time. Eighteen of the 38 (47%) cats had complete remission, 14 (37%) had partial remission, and 6 (16%) had no response. Duration of first remission was significantly longer for cats with complete remission (654 days) than for cats with partial remission (114 days). Median survival time for cats with complete remission (654 days) was significantly longer than median survival time for cats with partial remission (122 days) and for cats with no response (11 days). Results suggested that a high percentage of cats with lymphoma will respond to treatment with the University of Wisconsin-Madison chemotherapy protocol. Age, sex, anatomic form, and clinical stage were not significantly associated with duration of first response or survival time, but initial response to treatment was.
Swinburne, Nathaniel C; Biederman, Derek M; Besa, Cecilia; Tabori, Nora E; Fischman, Aaron M; Patel, Rahul S; Nowakowski, Francis Scott; Gunasekaran, Ganesh; Schwartz, Myron E; Lookstein, Robert A; Kim, Edward
2017-06-01
The optimal palliative treatment for unresectable intrahepatic cholangiocarcinoma (ICC) remains controversial. While selective internal radiation therapy (SIRT) using yttrium-90 microspheres is a well-accepted treatment for hepatocellular carcinoma, data related to its use for locally advanced ICC remain relatively scarce. Twenty-nine patients (mean age 66 ± 11 years; 15 female) with unresectable biopsy-proven ICC treated with SIRT between June 2008 and April 2015 were retrospectively evaluated for post-treatment toxicity, overall survival, and imaging response using response evaluation criteria in solid tumors (RECIST) 1.1 criteria. RECIST 1.1 response was evaluable following 26 treatments [complete response (CR):0, partial response (PR):3; stable disease (SD):16, progression of disease (PD):7]. Objective response rate (CR+PR) was 12%. Disease control rate (CR+PR+SD) was 73%. Median time to progression was 5.6 [95% confidence interval (CI): 0-12.0] months. Median survival following SIRT was 9.1 (95% CI: 1.7-16.4) months. Post-treatment survival was prolonged in patients with absence of extrahepatic disease (p = 0.03) and correlated with RECIST 1.1 response (p = 0.02). Toxicities were limited to grade I severity and occurred following 27% of treatments. These findings support the safe, effective use of SIRT for unresectable ICC. Post-treatment survival is prolonged in patients with absence of extrahepatic disease at baseline. RECIST 1.1 response following SIRT for ICC is predictive of survival.
Chen, Ligong; Schiffer, Jarad M; Dalton, Shannon; Sabourin, Carol L; Niemuth, Nancy A; Plikaytis, Brian D; Quinn, Conrad P
2014-11-01
Humoral and cell-mediated immune correlates of protection (COP) for inhalation anthrax in a rhesus macaque (Macaca mulatta) model were determined. The immunological and survival data were from 114 vaccinated and 23 control animals exposed to Bacillus anthracis spores at 12, 30, or 52 months after the first vaccination. The vaccinated animals received a 3-dose intramuscular priming series (3-i.m.) of anthrax vaccine adsorbed (AVA) (BioThrax) at 0, 1, and 6 months. The immune responses were modulated by administering a range of vaccine dilutions. Together with the vaccine dilution dose and interval between the first vaccination and challenge, each of 80 immune response variables to anthrax toxin protective antigen (PA) at every available study time point was analyzed as a potential COP by logistic regression penalized by least absolute shrinkage and selection operator (LASSO) or elastic net. The anti-PA IgG level at the last available time point before challenge (last) and lymphocyte stimulation index (SI) at months 2 and 6 were identified consistently as a COP. Anti-PA IgG levels and lethal toxin neutralization activity (TNA) at months 6 and 7 (peak) and the frequency of gamma interferon (IFN-γ)-secreting cells at month 6 also had statistically significant positive correlations with survival. The ratio of interleukin 4 (IL-4) mRNA to IFN-γ mRNA at month 6 also had a statistically significant negative correlation with survival. TNA had lower accuracy as a COP than did anti-PA IgG response. Following the 3-i.m. priming with AVA, the anti-PA IgG responses at the time of exposure or at month 7 were practicable and accurate metrics for correlating vaccine-induced immunity with protection against inhalation anthrax. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
Miao, Yi; Yan, Qin; Li, Shuangdi; Li, Bilan; Feng, Youji
2016-06-07
The aim of present study was to investigate the role of preoperative neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) used as prognostic markers for predicting chemotherapeutic response and survival outcomes in patients with epithelial ovarian cancer (EOC) who are receiving platinum-based chemotherapy. A total of 344 patients diagnosed with EOC who are receiving platinum-based chemotherapy from 2005 to 2010 in the hospital were enrolled. NLR and PLR were calculated from complete blood cell count taken before operation. The patients were divided into platinum-resistant (P-R) group and platinum-sensitive (P-S) group according to chemotherapeutic response. Clinicopathologic variables and outcomes were retrospectively collected and compared among groups. We used receiver operating characteristic (ROC) curves to calculate optimal cut-off values for NLR and PLR to predict chemotherapeutic response and prognosis. The AUC, sensitivity, specificity of NLR > 3.02 to predict platinum resistance were 0.819, 75.0% and 81.45%, respectively. The corresponding values of PLR > 207 were 0.727, 60.42% and 85.48%, respectively. Patients with lower value of NLR (NLR < 3.02) or PLR (PLR < 207) had a longer progression-free survival (PFS) and overall survival (OS). In multivariate analysis, NLR and PLR showed a significant association with PFS (hazard ratio [HR], 1.733; 95%CI, 1.225-2.453, P = 0.002 and HR, 1.952; 95%CI, 1.430-2.662, P < 0.001) and OS (HR, 1.616; 95%CI, 1.138-2.297, P = 0.007, and HR, 2.167; 95%CI, 1.565-3.000, P < 0.001). These results suggest that the assessment of NLR and PLR could assist the identification of patients with poor prognosis and had potential clinical value in predicting platinum resistance in patients with EOC.
Apatinib for advanced sarcoma: results from multiple institutions' off-label use in China.
Xie, Lu; Guo, Wei; Wang, Ye; Yan, Taiqiang; Ji, Tao; Xu, Jie
2018-04-06
Anti-angiogenesis Tyrosine kinase inhibitors (TKIs) have been proved to show promising effects on prolonging progression-free survival (PFS) for advanced sarcoma after failure of standard multimodal Therapy. Methylsulfonic apatinib is one of those TKIs which specifically inhibits VEGFR-2. This paper summarizes the experience of three Peking University affiliated hospitals in off-label use of apatinib in the treatment of extensively pre-treated sarcoma. We retrospectively analysed files of patients with advanced sarcoma not amenable to curative treatment, who were receiving an apatinib-containing regimen between June 1, 2015 and December 1, 2016. Fifty-six patients were included: 22 osteosarcoma, 10 Ewing's sarcoma, 3 chondrosarcoma and 21 soft tissue sarcoma. With median follow-up time of 6 months (range, 0.7-18.0 m), thirty-five (62.5%) patients had partial response, and disease was stable in 11 (19.6%). The 4-month and 6-month progression-free survival rates were 46.3 and 36.5%, respectively. The median duration of response was 3.8 months (95% CI 1.9-5.6 m), with much variability among disease subtypes. The median overall survival was 9.9 months (95% CI 7.6-12.2 m). Grade 3 and 4 toxicities were observed in 8 (14.3%) patients, the most common being hypertension, pneumothorax, wound-healing problems, anorexia, and rash or desquamation. Apatinib might be effective, with a high objective response rate, in an off-label study of sarcoma patients with advanced, previously treated disease. The duration of response was consistent with reports in different subtypes of sarcomas. Prospective trials of apatinib in the treatment of selected subtypes of sarcomas are needed. Retrospectively registered in the Medical Ethics Committee of Peking University People's Hospital, Peking University Shougang Hospital and Peking University International Hospital. The trial registration number is 2017PHB176-03 and the date of registration is January 20th 2017.
Marital status is a prognostic factor in amyotrophic lateral sclerosis.
Spataro, R; Volanti, P; Lo Coco, D; La Bella, V
2017-12-01
Several variables have been linked to a shorter survival in patients with amyotrophic lateral sclerosis (ALS), for example, female sex, older age, site of disease onset, rapid disease progression, and a relatively short diagnostic delay. With regard to marital status, previous studies suggested that living with a partner might be associated to a longer survival and a higher likelihood to proceed to tracheostomy. Therefore, to further strengthen this hypothesis, we investigated the role of marital status as a prognostic variable in a cohort of ALS patients. We performed a retrospective analysis on 501 consecutive ALS patients for which a complete disease's natural history and clinical/demographic data were available. At diagnosis, 409 patients (81.6%) were married or lived with a stable partner, whereas 92 patients (18.4%) were single/widowed/divorced. In our ALS cohort, being married was associated with a median longer survival (married, 35 months [24-50] vs unmarried, 27 months [18-42]; P<.004). Moreover, married and unmarried patients were significantly different in many clinical and demographic variables, including age at disease onset, gender, body mass index, and number of children. Cox regression analysis showed that age at onset, diagnostic delay, and marital status were independent predictors of survival. In unmarried patients, female sex was also significantly associated with shorter survival. Marital status is a prognostic factor in ALS, and it significantly affects survival. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Survival and selection of migrating salmon from capture-recapture models with individual traits
Zabel, R.W.; Wagner, T.; Congleton, J.L.; Smith, S.G.; Williams, J.G.
2005-01-01
Capture-recapture studies are powerful tools for studying animal population dynamics, providing information on population abundance, survival rates, population growth rates, and selection for phenotypic traits. In these studies, the probability of observing a tagged individual reflects both the probability of the individual surviving to the time of recapture and the probability of recapturing an animal, given that it is alive. If both of these probabilities are related to the same phenotypic trait, it can be difficult to distinguish effects on survival probabilities from effects on recapture probabilities. However, when animals are individually tagged and have multiple opportunities for recapture, we can properly partition observed trait-related variability into survival and recapture components. We present an overview of capture-recapture models that incorporate individual variability and develop methods to incorporate results from these models into estimates of population survival and selection for phenotypic traits. We conducted a series of simulations to understand the performance of these estimators and to assess the consequences of ignoring individual variability when it exists. In addition, we analyzed a large data set of > 153 000 juvenile chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) of known length that were PIT-tagged during their seaward migration. Both our simulations and the case study indicated that the ability to precisely estimate selection for phenotypic traits was greatly compromised when differential recapture probabilities were ignored. Estimates of population survival, however, were far more robust. In the chinook salmon and steelhead study, we consistently found that smaller fish had a greater probability of recapture. We also uncovered length-related survival relationships in over half of the release group/river segment combinations that we observed, but we found both positive and negative relationships between length and survival probability. These results have important implications for the management of salmonid populations. ?? 2005 by the Ecological Society of America.
Effects of harvest and climate on population dynamics of northern bobwhites in south Florida
Rolland, V.; Hostetler, J.A.; Hines, T.C.; Johnson, F.A.; Percival, H.F.; Oli, M.K.
2011-01-01
Context Hunting-related (hereafter harvest) mortality is assumed to be compensatory in many exploited species. However, when harvest mortality is additive, hunting can lead to population declines, especially on public land where hunting pressure can be intense. Recent studies indicate that excessive hunting may have contributed to the decline of a northern bobwhite (Colinus virginianus) population in south Florida. Aims This study aimed to estimate population growth rates to determine potential and actual contribution of vital rates to annual changes in population growth rates, and to evaluate the role of harvest and climatic variables on bobwhite population decline. Methods We used demographic parameters estimated from a six-year study to parameterise population matrix models and conduct prospective and retrospective perturbation analyses. Key results The stochastic population growth rate (?? S=0.144) was proportionally more sensitive to adult winter survival and survival of fledglings, nests and broods from first nesting attempts; the same variables were primarily responsible for annual changes in population growth rate. Demographic parameters associated with second nesting attempts made virtually no contribution to population growth rate. All harvest scenarios consistently revealed a substantial impact of harvest on bobwhite population dynamics. If the lowest harvest level recorded in the study period (i.e. 0.08 birds harvested per day per km2 in 2008) was applied, S would increase by 32.1%. Winter temperatures and precipitation negatively affected winter survival, and precipitation acted synergistically with harvest in affecting winter survival. Conclusions Our results suggest that reduction in winter survival due to overharvest has been an important cause of the decline in our study population, but that climatic factors might have also played a role. Thus, for management actions to be effective, assessing the contribution of primary (e.g. harvesting) but also secondary factors (e.g. climate) to population decline may be necessary. Implications Reducing hunting pressure would be necessary for the recovery of the bobwhite population at our study site. In addition, an adaptive harvest management strategy that considers weather conditions in setting harvest quota would help reverse the population decline further. ?? 2011 CSIRO.
The Impact of Water Table Drawdown and Drying on Subterranean Aquatic Fauna in In-Vitro Experiments
Stumpp, Christine; Hose, Grant C.
2013-01-01
The abstraction of groundwater is a global phenomenon that directly threatens groundwater ecosystems. Despite the global significance of this issue, the impact of groundwater abstraction and the lowering of groundwater tables on biota is poorly known. The aim of this study is to determine the impacts of groundwater drawdown in unconfined aquifers on the distribution of fauna close to the water table, and the tolerance of groundwater fauna to sediment drying once water levels have declined. A series of column experiments were conducted to investigate the depth distribution of different stygofauna (Syncarida and Copepoda) under saturated conditions and after fast and slow water table declines. Further, the survival of stygofauna under conditions of reduced sediment water content was tested. The distribution and response of stygofauna to water drawdown was taxon specific, but with the common response of some fauna being stranded by water level decline. So too, the survival of stygofauna under different levels of sediment saturation was variable. Syncarida were better able to tolerate drying conditions than the Copepoda, but mortality of all groups increased with decreasing sediment water content. The results of this work provide new understanding of the response of fauna to water table drawdown. Such improved understanding is necessary for sustainable use of groundwater, and allows for targeted strategies to better manage groundwater abstraction and maintain groundwater biodiversity. PMID:24278111
Zugck, C; Krüger, C; Kell, R; Körber, S; Schellberg, D; Kübler, W; Haass, M
2001-10-01
The performance of a US-American scoring system (Heart Failure Survival Score, HFSS) was prospectively evaluated in a sample of ambulatory patients with congestive heart failure (CHF). Additionally, it was investigated whether the HFSS might be simplified by assessment of the distance ambulated during a 6-min walk test (6'WT) instead of determination of peak oxygen uptake (peak VO(2)). In 208 middle-aged CHF patients (age 54+/-10 years, 82% male, NYHA class 2.3+/-0.7; follow-up 28+/-14 months) the seven variables of the HFSS: CHF aetiology; heart rate; mean arterial pressure; serum sodium concentration; intraventricular conduction time; left ventricular ejection fraction (LVEF); and peak VO(2), were determined. Additionally, a 6'WT was performed. The HFSS allowed discrimination between patients at low, medium and high risk, with mortality rates of 16, 39 and 50%, respectively. However, the prognostic power of the HFSS was not superior to a two-variable model consisting only of LVEF and peak VO(2). The areas under the receiver operating curves (AUC) for prediction of 1-year survival were even higher for the two-variable model (0.84 vs. 0.74, P<0.05). Replacing peak VO(2) with 6'WT resulted in a similar AUC (0.83). The HFSS continued to predict survival when applied to this patient sample. However, the HFSS was inferior to a two-variable model containing only LVEF and either peak VO(2) or 6'WT. As the 6'WT requires no sophisticated equipment, a simplified two-variable model containing only LVEF and 6'WT may be more widely applicable, and is therefore recommended.
Work, family, and gender: elements for a theory of work-family balance.
Cantera, Leonor M; Cubells, Ma Eugenia; Martínez, Luz Ma; Blanch, Josep M
2009-11-01
Over last century, work was not only a means of economic survival, but also a very strong factor of psychological structuring and of organization of personal, family, and everyday life. The new world of work provides new challenges to the balance of work and family life. A questionnaire was administered to a sample of 453 people with the aim of analyzing the relation between variables such as family burdens and domestic responsibilities, and the appraisal of work and family, values involved in work-family balance. The results of this study show that, in the present economic and cultural context, assuming family burdens and domestic responsibilities increases the positive appraisal of work and family, both in men and women. This has theoretical and practical implications concerning the challenge of work-family balance.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kirkland, Robert S.; Nanda, Ronica H., E-mail: rhazari@emory.edu; Alazraki, Adina
Purpose: Chest computed tomography (CT) is currently accepted as the main modality for initial disease staging and response assessment in Wilms tumor (WT). However, there is great variability in the number and size of lung metastases at the time of diagnosis and after induction chemotherapy. There is a lack of clinical evidence as to how this variability in tumor burden affects choice of therapy and disease outcome. This study sought to evaluate a previously proposed lung metastases risk stratification system based on CT findings and clinical outcomes in stage IV WT patients. Methods and Materials: Thirty-five pediatric patients with amore » diagnosis of stage IV WT with evaluable pre- and postdiagnosis CT scans between 1997 and 2012 were included in the analysis. Patients were divided into low-, intermediate-, and high-risk categories based on the size and number of pulmonary metastases before and after 6 weeks of chemotherapy. Association of the lung risk groups with lung recurrence-free survival and overall survival at each time point was analyzed with relevant covariates. Results: Risk group distribution both at diagnosis and after induction chemotherapy was not influenced by tumor histology. Initial risk grouping suggested an association with disease-free survival at 5 years (P=.074); however, the most significant correlation was with postinduction chemotherapy disease status (P=.027). In patients with an intermediate or high burden of disease after 6 weeks of chemotherapy, despite receiving whole-lung and boost irradiation, survival outcomes were poorer. Conclusions: Pulmonary tumor burden in stage IV WT on chest CT can predict disease outcome. Patients with intermediate- or low-risk disease, especially after induction therapy, have a higher risk for recurrence. After prospective validation, this method may become a valuable tool in adaptation of therapy to improve outcome.« less
THE ROLE OF INDIVIDUAL VARIABILITY IN POPULATION DYNAMICS UNDER CHANGING ENVIRONMENTAL CONDITIONS
Environmental variability can influence species distributions through changes in
survival, fecundity, behavior, and metabolic activities. As worldwide coastal populations rise, the associated deforestation and development can increase both quantities and variability in runoff...
Bradley, Darcy; Conklin, Eric; Papastamatiou, Yannis P.; McCauley, Douglas J.; Pollock, Kydd; Kendall, Bruce E.; Gaines, Steven D.; Caselle, Jennifer E.
2017-01-01
For broadly distributed, often overexploited species such as elasmobranchs (sharks and rays), conservation management would benefit from understanding how life history traits change in response to local environmental and ecological factors. However, fishing obfuscates this objective by causing complex and often mixed effects on the life histories of target species. Disentangling the many drivers of life history variability requires knowledge of elasmobranch populations in the absence of fishing, which is rarely available. Here, we describe the growth, maximum size, sex ratios, size at maturity, and offer a direct estimate of survival of an unfished population of grey reef sharks (Carcharhinus amblyrhynchos) using data from an eight year tag-recapture study. We then synthesized published information on the life history of C. amblyrhynchos from across its geographic range, and for the first time, we attempted to disentangle the contribution of fishing from geographic variation in an elasmobranch species. For Palmyra’s unfished C. amblyrhynchos population, the von Bertalanffy growth function (VBGF) growth coefficient k was 0.05 and asymptotic length L∞ was 163.3 cm total length (TL). Maximum size was 175.5 cm TL from a female shark, length at maturity was estimated at 116.7–123.2 cm TL for male sharks, maximum lifespan estimated from VBGF parameters was 18.1 years for both sexes combined, and annual survival was 0.74 year-1. Consistent with findings from studies on other elasmobranch species, we found significant intraspecific variability in reported life history traits of C. amblyrhynchos. However, contrary to what others have reported, we did not find consistent patterns in life history variability as a function of biogeography or fishing. Ultimately, the substantial, but not yet predictable variability in life history traits observed for C. amblyrhynchos across its geographic range suggests that regional management may be necessary to set sustainable harvest targets and to recover this and other shark species globally. PMID:28207874
Bradley, Darcy; Conklin, Eric; Papastamatiou, Yannis P; McCauley, Douglas J; Pollock, Kydd; Kendall, Bruce E; Gaines, Steven D; Caselle, Jennifer E
2017-01-01
For broadly distributed, often overexploited species such as elasmobranchs (sharks and rays), conservation management would benefit from understanding how life history traits change in response to local environmental and ecological factors. However, fishing obfuscates this objective by causing complex and often mixed effects on the life histories of target species. Disentangling the many drivers of life history variability requires knowledge of elasmobranch populations in the absence of fishing, which is rarely available. Here, we describe the growth, maximum size, sex ratios, size at maturity, and offer a direct estimate of survival of an unfished population of grey reef sharks (Carcharhinus amblyrhynchos) using data from an eight year tag-recapture study. We then synthesized published information on the life history of C. amblyrhynchos from across its geographic range, and for the first time, we attempted to disentangle the contribution of fishing from geographic variation in an elasmobranch species. For Palmyra's unfished C. amblyrhynchos population, the von Bertalanffy growth function (VBGF) growth coefficient k was 0.05 and asymptotic length L∞ was 163.3 cm total length (TL). Maximum size was 175.5 cm TL from a female shark, length at maturity was estimated at 116.7-123.2 cm TL for male sharks, maximum lifespan estimated from VBGF parameters was 18.1 years for both sexes combined, and annual survival was 0.74 year-1. Consistent with findings from studies on other elasmobranch species, we found significant intraspecific variability in reported life history traits of C. amblyrhynchos. However, contrary to what others have reported, we did not find consistent patterns in life history variability as a function of biogeography or fishing. Ultimately, the substantial, but not yet predictable variability in life history traits observed for C. amblyrhynchos across its geographic range suggests that regional management may be necessary to set sustainable harvest targets and to recover this and other shark species globally.
The Art of Being Flexible: How to Escape from Shade, Salt, and Drought1
Pierik, Ronald; Testerink, Christa
2014-01-01
Environmental stresses, such as shading of the shoot, drought, and soil salinity, threaten plant growth, yield, and survival. Plants can alleviate the impact of these stresses through various modes of phenotypic plasticity, such as shade avoidance and halotropism. Here, we review the current state of knowledge regarding the mechanisms that control plant developmental responses to shade, salt, and drought stress. We discuss plant hormones and cellular signaling pathways that control shoot branching and elongation responses to shade and root architecture modulation in response to drought and salinity. Because belowground stresses also result in aboveground changes and vice versa, we then outline how a wider palette of plant phenotypic traits is affected by the individual stresses. Consequently, we argue for a research agenda that integrates multiple plant organs, responses, and stresses. This will generate the scientific understanding needed for future crop improvement programs aiming at crops that can maintain yields under variable and suboptimal conditions. PMID:24972713
Climate variability drives population cycling and synchrony
Lars Y. Pomara; Benjamin Zuckerberg
2017-01-01
Aim There is mounting concern that climate change will lead to the collapse of cyclic population dynamics, yet the influence of climate variability on population cycling remains poorly understood. We hypothesized that variability in survival and fecundity, driven by climate variability at different points in the life cycle, scales up from...
Vera, L.; Pérez-Beteta, J.; Molina, D.; Borrás, J. M.; Benavides, M.; Barcia, J. A.; Velásquez, C.; Albillo, D.; Lara, P.; Pérez-García, V. M.
2017-01-01
Abstract Introduction: Machine learning methods are integrated in clinical research studies due to their strong capability to discover parameters having a high information content and their predictive combined potential. Several studies have been developed using glioblastoma patient’s imaging data. Many of them have focused on including large numbers of variables, mostly two-dimensional textural features and/or genomic data, regardless of their meaning or potential clinical relevance. Materials and methods: 193 glioblastoma patients were included in the study. Preoperative 3D magnetic resonance images were collected and semi-automatically segmented using an in-house software. After segmentation, a database of 90 parameters including geometrical and textural image-based measures together with patients’ clinical data (including age, survival, type of treatment, etc.) was constructed. The criterion for including variables in the study was that they had either shown individual impact on survival in single or multivariate analyses or have a precise clinical or geometrical meaning. These variables were used to perform several machine learning experiments. In a first set of computational cross-validation experiments based on regression trees, those attributes showing the highest information measures were extracted. In the second phase, more sophisticated learning methods were employed in order to validate the potential of the previous variables predicting survival. Concretely support vector machines, neural networks and sparse grid methods were used. Results: Variables showing high information measure in the first phase provided the best prediction results in the second phase. Specifically, patient age, Stupp regimen and a geometrical measure related with the irregularity of contrast-enhancing areas were the variables showing the highest information measure in the first stage. For the second phase, the combinations of patient age and Stupp regimen together with one tumor geometrical measure and one tumor heterogeneity feature reached the best quality prediction. Conclusions: Advanced machine learning methods identified the parameters with the highest information measure and survival predictive potential. The uninformed machine learning methods identified a novel feature measure with direct impact on survival. Used in combination with other previously known variables multi-indexes can be defined that can help in tumor characterization and prognosis prediction. Recent advances on the definition of those multi-indexes will be reported in the conference. Funding: James S. Mc. Donnell Foundation (USA) 21st Century Science Initiative in Mathematical and Complex Systems Approaches for Brain Cancer [Collaborative award 220020450 and planning grant 220020420], MINECO/FEDER [MTM2015-71200-R], JCCM [PEII-2014-031-P].
Tomasello, Gianluca; Petrelli, Fausto; Ghidini, Michele; Russo, Alessandro; Passalacqua, Rodolfo; Barni, Sandro
2017-07-13
The combination of fluorouracil, oxaliplatin, and irinotecan plus bevacizumab (FOLFOXIRI-Bev) is an established and effective first-line chemotherapy regimen for metastatic colorectal cancer. However, resection rates of metastases and overall survival with this schedule have never been systematically evaluated in published studies including, but not limited to, the TRIBE (TRIplet plus BEvacizumab) trial. To assess the clinical efficacy of FOLFOXIRI-Bev, including outcomes and rates of surgical conversions. A systematic review was conducted in October 2016 in concordance with the PRISMA guidelines of PubMed, the Cochrane Central Register of Controlled Trials, SCOPUS, Web of Science, Google Scholar, CINAHL, Ovid, and EMBASE using the terms FOLFOXIRI and bevacizumab and (colorectal cancer). Clinical trials, retrospective case series, and prospective case series that used FOLFOXIRI-Bev for the treatment of initially unresectable metastatic colorectal cancer in humans were included. Individual case reports and retrospective case series with fewer than 10 patients were excluded. Data were extracted independently by 2 reviewers on a predesigned, standardized form. Ultimately, data were aggregated to obtain the pooled effect size of efficacy, according to the random-effects model and weighted for the number of patients included in each trial. Median overall survival and progression-free survival, overall response rates, and rates of R0 surgical conversions and overall surgical conversions. Eleven FOLFOXIRI-Bev studies published between 2010 and 2016 met the inclusion criteria and were pooled for analysis. The studies included 889 patients, with 877 patients clinically evaluable for overall response rates. The objective response rate to FOLFOXIRI-Bev was 69% (95% CI, 65%-72%; I2 = 25%). The rate of overall surgical conversions was 39.1% (95% CI, 26.9%-52.8%), and the rate of R0 surgical conversions was 28.1% (95% CI, 18.1%-40.8%). Median pooled overall survival was 30.2 months (95% CI, 26.5-33.7 months) in 6 trials with data available, and progression-free survival was 12.4 months (95% CI, 10.0-14.3 months) in 9 trials with data available. In meta-regression analysis, variables significantly associated with conversion surgery were disease limited to the liver and a higher median number of cycles (close to 12). For patients with surgically unresectable metastatic colorectal cancer, FOLFOXIRI-Bev is associated with a significant overall response rate. Such an effective regimen leads to a probability of surgical conversion of distant metastases approaching 40%, with more than one-fourth of patients having an R0 resection.
NASA Technical Reports Server (NTRS)
Dolvin, Douglas J.
1992-01-01
The superior survivability of a multirole fighter is dependent upon balanced integration of technologies for reduced vulnerability and susceptability. The objective is to develop a methodology for structural design optimization with survivability dependent constraints. The design criteria for optimization will be survivability in a tactical laser environment. The following analyses are studied to establish a dependent design relationship between structural weight and survivability: (1) develop a physically linked global design model of survivability variables; and (2) apply conventional constraints to quantify survivability dependent design. It was not possible to develop an exact approach which would include all aspects of survivability dependent design, therefore guidelines are offered for solving similar problems.
Retrospective cohort study of the clinical performance of 1-stage dental implants.
Carr, Alan B; Choi, Yong-Geun; Eckert, Steven E; Desjardins, Ronald P
2003-01-01
To evaluate long-term clinical performance of 1-stage dental implant prostheses at a single clinic, emphasizing clinical and demographic characteristics that affect implant survival. Dental records of all 308 patients (674 implants) treated with 1-stage implants at Mayo Clinic from October 1993 through May 2000 were reviewed from implant placement to last visit. Exposure and outcome variables affecting performance were collected separately to control bias in the data collection process. Additional confounding factors (age and sex) were adjusted with the stratified Cox proportional hazards model. Implant survival was determined by means of a Kaplan-Meier survival estimate. The log-rank test was used to determine the role of clinical and demographic variables in implant survival. The relative risk associated with the possible effect of clinical and demographic variables on implant survival was estimated with the Cox proportional hazards model. The implant survival rate (n = 654 implants) was 97% (mean +/- SD follow-up, 21.0 +/- 18.8 months; range, 1 to 78 months). Performance bias was limited because nearly all patients were treated by 1 prosthodontist. Two implants failed after loading (6 and 9 months). The incidence of complications was less than 4%. Among the implant failures, use of heterogeneous bone graft was associated with 4.8 times more failures than was use of autogenous bone graft (P = .04). After augmentation, delaying implant placement for 5 to 6 months resulted in 8.6 times more failures than the rate after earlier placement (P < .001). Retrospective review of the clinical performance of a 1-stage dental implant system yielded a 97% survival rate, with no failures noted after 13 months. Prosthetic complications were low, especially for fixed implant prostheses. Clinical performance of 1-stage dental implant prostheses between 1993 and 2000 demonstrated a high level of predictability.
Formica, Vincenzo; Benassi, Michaela; Del Vecchio Blanco, Giovanna; Doldo, Elena; Martano, Laura; Portarena, Ilaria; Nardecchia, Antonella; Lucchetti, Jessica; Morelli, Cristina; Giudice, Emilia; Rossi, Piero; Anselmo, Alessandro; Sileri, Pierpaolo; Sica, Giuseppe; Orlandi, Augusto; Santoni, Riccardo; Roselli, Mario
2018-05-02
A platinum salt (oxaliplatin or cisplatin) is widely used to enhance chemoradation (CRT) response. The potential of cisplatin in neoadjuvant CRT for locally advanced rectal cancer (LARC) has not been fully investigated. Consecutive patients with histologically confirmed LARC were treated with standard pelvic radiotherapy and concurrent cisplatin plus capecitabine (CisCape CRT). Surgery and eight cycles of adjuvant FOLFOX4 were offered to all patients after CRT. Common biochemical variables and key germline genetic polymorphisms were analyzed as predictors of pathological complete response (pCR). Fifty-one patients were enrolled. pCR (regression AJCC grade 0) was documented in 7 patients (14%), nearly complete response (AJCC grade 1) in 10 pts. There was a strong association between disease-free survival and AJCC grade (p 0.0047). Grade 3-4 toxicities (mainly diarrhea) was observed in 41% of patients. Among all analyzed variables, baseline hemoglobin (Hb) was significantly associated with AJCC grade 0-1 response (p 0.027). As for the pharmacogenetic analysis, XRCC1 rs25487 polymorphism was significantly associated with AJCC grade 0-1, Odds Ratio 25.8, p 0.049. AJCC grade 0-1 response rate for patients with high Hb and/or XRCC1 rs25487 G/G genotype was as high as 57%. Baseline Hb and XRCC1 polymorphisms are valuable selection criteria for the CisCape CRT regimen, given its otherwise meaningful toxicity.
von Arx, Georg; Archer, Steven R; Hughes, Malcolm K
2012-05-01
Plasticity in structural and functional traits related to water balance may determine plant performance and survival in ecosystems characterized by water limitation or high levels of rainfall variability, particularly in perennial herbaceous species with long generation cycles. This paper addresses whether and the extent to which several such seasonal to long-term traits respond to changes in moisture availability. Using a novel approach that integrates ecology, physiology and anatomy, a comparison was made of lifetime functional traits in the root xylem of a long-lived perennial herb (Potentilla diversifolia, Rosaceae) growing in dry habitats with those of nearby individuals growing where soil moisture had been supplemented for 14 years. Traditional parameters such as specific leaf area (SLA) and above-ground growth were also assessed. Individuals from the site receiving supplemental moisture consistently showed significant responses in all considered traits related to water balance: SLA was greater by 24 %; roots developed 19 % less starch storing tissue, an indicator for drought-stress tolerance; and vessel size distributions shifted towards wider elements that collectively conducted water 54 % more efficiently - but only during the years for which moisture was supplemented. In contrast, above-ground growth parameters showed insignificant or inconsistent responses. The phenotypic changes documented represent consistent, dynamic responses to increased moisture availability that should increase plant competitive ability. The functional plasticity of xylem anatomy quantified in this study constitutes a mechanistic basis for anticipating the differential success of plant species in response to climate variability and change, particularly where water limitation occurs.
NASA Astrophysics Data System (ADS)
Karaoz, U.; Couradeau, E.; da Rocha, U. N.; Chien Lim, H.; Garcia-Pichel, F.; Northen, T.; Brodie, E.
2016-12-01
Biological soil crusts (biocrusts), critical components of dryland ecosystem, successionally develop to deliver a suite of ecosystem services. Biocrust assemblages are extremely well adapted to survive desiccation and then take advantage of pulses of precipitation typical of arid climate, yet we know little about how these microbial communities of different developmental stages respond to wetup. Here we focus on the wetup response of incipient cyanobacterial crusts as they progress from "light" to "dark". We sampled a cyanobacterial biocrust chronosequence pre- (dry) and post-wetup within a day, and used high-throughput 16S rRNA sequencing to decipher wetup response of microbial communities. Overall, changes in phylogenetic beta-diversity attributable to crust successional stage were at least as large as those for wetup. Notably, more mature crusts showed significantly higher resistance to pulse hydration. Taxonomically, a drastic bloom of handful Firmicutes taxa, primarily from Bacillales order was apparent 18 hrs. after wetup. The wetup response of filamentous cyanobacteria was variable across the successional gradient, with populations collapsing in less developed light crusts but rising in dark crusts. Strong phylogenetic clustering that significantly increased with crust development and wetup suggested conservation and an evolutionary basis for the response of biocrust microbial communities to wetup. The consistent Bacillales bloom accompanied by the variable collapse of the Microcoleus we documented across the successional gradient suggests that the cumulative effects of increased precipitation frequencies on C cycling will depend on crust maturity.
Adam de Beaumais, Tiphaine; Jacqz-Aigrain, Evelyne
2012-09-01
The backbone of drug therapy used in acute lymphoblastic leukemia (ALL) in children includes 6-mercaptopurine (6-MP). Intracellular metabolism of this prodrug is a key component of the therapeutic response. Many metabolizing enzymes are involved in 6-MP disposition and active 6-MP metabolites are represented by 6-thioguanine nucleotides (6-TGN) and methylated metabolites primarily methylated by the thiopurine S-methyltransferase enzyme (TPMT). The genetic polymorphism affecting TPMT activity displays an important inter-subject variability in metabolites pharmacokinetics and influences the balance between 6-MP efficacy and toxicity: patients with high 6-TGN levels are at risk of myelosuppression while patients with high levels of methylated derivates are at hepatotoxic risk. However, the genetic TPMT polymorphism does not explain all 6-MP adverse events and some severe toxicities leading to life-threatening conditions remain unexplained. Additional single nucleotide polymorphisms (SNPs) in genes encoding enzymes involved in 6-MP metabolism and 6-MP transporters may also be responsible for this inter-individual 6-MP response variability. This review presents the pharmacogenetic aspects of 6-MP metabolism in great detail. We have focused on published data on ALL treatment supporting the great potential of 6-MP pharmacogenetics to improve efficacy, tolerance, and event-free survival rates in children with ALL.
NASA Astrophysics Data System (ADS)
Guadagno, C. R.; Beverly, D.; Pleban, J. R.; Speckman, H. N.; Ewers, B. E.; Weinig, C.
2017-12-01
Aridity is one of the most pronounced environmental limits to plant survival, and understanding how plants respond to drought and recovery is crucial for predicting impacts on managed and natural ecosystems. Changes in soil moisture conditions induce a suite of physiological responses from the cell to ecosystem scale, complicating the assessment of drought effects. Characterizing early indicators of water scarcity across species can inform biophysical models with improved understanding of plant hydraulics. While indexes exist for drought monitoring across scales, many are unable to identify imminent vegetative drought. We explore a method of early diagnosis using leaf-level and kinetic imaging measures of variable chlorophyll a fluorescence. This is a fast and reliable tool capturing leaf physiological changes in advance of changes in NDVI or passive solar induced fluorescence. Both image and leaf level Pulse Amplitude Method (PAM) measurements illustrate the utility of variable chlorophyll a fluorescence for monitoring vegetative drought. Variable fluorescence was monitored across populations of crops, desert shrubs, montane conifers and riparian deciduous trees under variable water regimes. We found a strong correlation (R = 0.85) between the maximum efficiency of photosystem II measured using variable fluorescence (Fv'Fm') and leaf level electrolyte leakage, a proximal cause of drought stress induced by cellular damage in leaves. This association was confirmed in two gymnosperm species (Picea engelmannii and Pinus contorta) and for diverse varieties of the crop species Brassica rapa. The use of chlorophyll a fluorescence per image also allowed for early detection of drought in aspen (Populus tremuloides). These results provide evidence that variable chlorophyll fluorescence decreases between 25% and 70% in mild and severely droughted twigs with respect to ones collected from trees in wet soil conditions. While current systems for monitoring variable fluorescence are limited in scale, chlorophyll fluorescence comprises an indicator of drought stress across multiple spatial scales, from leaf to ecosystem level.
Long-term demographic consequences of habitat fragmentation to a tropical understory bird community
Korfanta, N.M.; Newmark, W.D.; Kauffman, M.J.
2012-01-01
Tropical deforestation continues to cause population declines and local extinctions in centers of avian diversity and endemism. Although local species extinctions stem from reductions in demographic rates, little is known about how habitat fragmentation influences survival of tropical bird populations or the relative importance of survival and fecundity in ultimately shaping communities. We analyzed 22 years of mark-recapture data to assess how fragmentation influenced apparent survival, recruitment, and realized population growth rate within 22 forest understory bird species in the Usambara Mountains, Tanzania. This represents the first such effort, in either tropical or temperate systems, to characterize the effect of deforestation on avian survival across such a broad suite of species. Long-term demographic analysis of this suite of species experiencing the same fragmented environment revealed considerable variability in species' responses to fragmentation, in addition to general patterns that emerged from comparison among species. Across the understory bird community as a whole, we found significantly lower apparent survival and realized population growth rate in small fragments relative to large, demonstrating fragmentation effects to demographic rates long after habitat loss. Demographic rates were depressed across five feeding guilds, suggesting that fragmentation sensitivity was not limited to insectivores. Seniority analyses, together with a positive effect of fragmentation on recruitment, indicated that depressed apparent survival was the primary driver of population declines and observed extinctions. We also found a landscape effect, with lower vital rates in one mountain range relative to another, suggesting that fragmentation effects may add to other large-scale drivers of population decline. Overall, realized population growth rate (λ) estimates were < 1 for most species, suggesting that future population persistence even within large forest fragments is uncertain in this biodiversity hotspot.
Martin, Lisa; Watanabe, Sharon; Fainsinger, Robin; Lau, Francis; Ghosh, Sunita; Quan, Hue; Atkins, Marlis; Fassbender, Konrad; Downing, G Michael; Baracos, Vickie
2010-10-01
To determine whether elements of a standard nutritional screening assessment are independently prognostic of survival in patients with advanced cancer. A prospective nested cohort of patients with metastatic cancer were accrued from different units of a Regional Palliative Care Program. Patients completed a nutritional screen on admission. Data included age, sex, cancer site, height, weight history, dietary intake, 13 nutrition impact symptoms, and patient- and physician-reported performance status (PS). Univariate and multivariate survival analyses were conducted. Concordance statistics (c-statistics) were used to test the predictive accuracy of models based on training and validation sets; a c-statistic of 0.5 indicates the model predicts the outcome as well as chance; perfect prediction has a c-statistic of 1.0. A training set of patients in palliative home care (n = 1,164) was used to identify prognostic variables. Primary disease site, PS, short-term weight change (either gain or loss), dietary intake, and dysphagia predicted survival in multivariate analysis (P < .05). A model including only patients separated by disease site and PS with high c-statistics between predicted and observed responses for survival in the training set (0.90) and validation set (0.88; n = 603). The addition of weight change, dietary intake, and dysphagia did not further improve the c-statistic of the model. The c-statistic was also not altered by substituting physician-rated palliative PS for patient-reported PS. We demonstrate a high probability of concordance between predicted and observed survival for patients in distinct palliative care settings (home care, tertiary inpatient, ambulatory outpatient) based on patient-reported information.
Variable ecological conditions promote male helping by changing banded mongoose group composition.
Marshall, Harry H; Sanderson, Jennifer L; Mwanghuya, Francis; Businge, Robert; Kyabulima, Solomon; Hares, Michelle C; Inzani, Emma; Kalema-Zikusoka, Gladys; Mwesige, Kenneth; Thompson, Faye J; Vitikainen, Emma I K; Cant, Michael A
2016-01-01
Ecological conditions are expected to have an important influence on individuals' investment in cooperative care. However, the nature of their effects is unclear: both favorable and unfavorable conditions have been found to promote helping behavior. Recent studies provide a possible explanation for these conflicting results by suggesting that increased ecological variability, rather than changes in mean conditions, promote cooperative care. However, no study has tested whether increased ecological variability promotes individual-level helping behavior or the mechanisms involved. We test this hypothesis in a long-term study population of the cooperatively breeding banded mongoose, Mungos mungo , using 14 years of behavioral and meteorological data to explore how the mean and variability of ecological conditions influence individual behavior, body condition, and survival. Female body condition was more sensitive to changes in rainfall leading to poorer female survival and pronounced male-biased group compositions after periods of high rainfall variability. After such periods, older males invested more in helping behavior, potentially because they had fewer mating opportunities. These results provide the first empirical evidence for increased individual helping effort in more variable ecological conditions and suggest this arises because of individual differences in the effect of ecological conditions on body condition and survival, and the knock-on effect on social group composition. Individual differences in sensitivity to environmental variability, and the impacts this has on the internal structure and composition of animal groups, can exert a strong influence on the evolution and maintenance of social behaviors, such as cooperative care.
Variable ecological conditions promote male helping by changing banded mongoose group composition
Sanderson, Jennifer L.; Mwanghuya, Francis; Businge, Robert; Kyabulima, Solomon; Hares, Michelle C.; Inzani, Emma; Kalema-Zikusoka, Gladys; Mwesige, Kenneth; Thompson, Faye J.; Vitikainen, Emma I. K.; Cant, Michael A.
2016-01-01
Ecological conditions are expected to have an important influence on individuals’ investment in cooperative care. However, the nature of their effects is unclear: both favorable and unfavorable conditions have been found to promote helping behavior. Recent studies provide a possible explanation for these conflicting results by suggesting that increased ecological variability, rather than changes in mean conditions, promote cooperative care. However, no study has tested whether increased ecological variability promotes individual-level helping behavior or the mechanisms involved. We test this hypothesis in a long-term study population of the cooperatively breeding banded mongoose, Mungos mungo, using 14 years of behavioral and meteorological data to explore how the mean and variability of ecological conditions influence individual behavior, body condition, and survival. Female body condition was more sensitive to changes in rainfall leading to poorer female survival and pronounced male-biased group compositions after periods of high rainfall variability. After such periods, older males invested more in helping behavior, potentially because they had fewer mating opportunities. These results provide the first empirical evidence for increased individual helping effort in more variable ecological conditions and suggest this arises because of individual differences in the effect of ecological conditions on body condition and survival, and the knock-on effect on social group composition. Individual differences in sensitivity to environmental variability, and the impacts this has on the internal structure and composition of animal groups, can exert a strong influence on the evolution and maintenance of social behaviors, such as cooperative care. PMID:27418750
Leontovich, Alexey A; Dronca, Roxana S; Nevala, Wendy K; Thompson, Michael A; Kottschade, Lisa A; Ivanov, Leonid V; Markovic, Svetomir N
2017-02-01
Skin cancer affects more individuals in the USA than any other malignancy and malignant melanoma is particularly deadly because of its metastatic potential. Melanoma has been recognized as one of the most immunogenic malignancies; therefore, understanding the mechanisms of tumor-immune interaction is key for developing more efficient treatments. As the tumor microenvironment shows an immunosuppressive action, immunotherapeutic agents promoting endogenous immune response to cancer have been tested (interleukin-2, anticytotoxic-T-lymphocyte-associated antigen 4, and antiprogrammed cell death protein 1 monoclonal antibodies) as well as combinations of cytotoxic chemotherapy agents and inhibitors of angiogenesis (taxol/carboplatin/avastin). However, clinical outcomes are variable, with only a minority of patients achieving durable complete responses. The variability of immune homeostasis, which may be more active or more tolerant at any given time, in cancer patients and the interaction of the immune system with the tumor could explain the inconsistency in clinical outcomes among these patients. Recently, the role of the lymphocyte-to-monocyte-ratio (LMR) in the peripheral blood has been investigated and has been proven to be an independent predictor of survival in different hematological malignancies and in solid tumors. In melanoma, our group has validated the significance of LMR as a predictor of relapse after resection of advanced melanoma. In this study, we examined the dynamics in the immune system of patients with advanced melanoma by performing serial multiday concentration measurements of cytokines and immune cell subsets in the peripheral blood. The analysis of outcomes of chemotherapy administration as related to LMR on the day of treatment initiation showed that progression-free survival was improved in the patients who received chemotherapy on the day when LMR was elevated.
Ibáñez, Inés; McCarthy-Neumann, Sarah
2014-02-01
Understanding the dynamics of tree establishment is critical to assess forests' composition, management practices, and current responses to global change. We carried out a field seedling transplant experiment to assess not only the direct effects of resources influencing recruitment of four tree species, but also their indirect and combined effects. Our analysis integrated first growing season demographic data together with estimates of mycorrhizal fungal colonization and resource availability (light, soil moisture, and soil nitrogen). Only by considering both the direct and indirect effects of resources we were able to account for most of the variability observed during seedling recruitment. Contrary to expectations, increasing light levels were not always beneficial for recruitment even in low light habitats, and soil moisture availability benefited seedling growth but not survival. In addition, mycorrhizal fungal colonization was not always favored by high light levels or by increasing soil moisture. Seedling survival for all species was lower in plots with higher arbuscular mycorrhizal fungi, while the association with ectomycorrhizal fungi varied from beneficial to detrimental. When integrating the direct, indirect, and interactive effects of resource availability and mycorrhizal fungal colonization on tree recruitment dynamics we found that species responded in a nonlinear fashion to increasing resource levels, and we also identified thresholds, i.e., shifts in the direction of the response, along the resource gradient. Our integrated assessment considerably outperformed a null model where only direct effects of resources were accounted for. These results illustrate how the combination of direct, indirect, and combined effects of driving variables better represents the complexity of the processes determining tree species recruitment than simple resource availability mechanisms.
Sánchez-Gómez, David; Valladares, Fernando; Zavala, Miguel A
2006-11-01
We investigated the differential roles of physiological and morphological features on seedling survivorship along an experimental irradiance gradient in four dominant species of cool temperate-Mediterranean forests (Quercus robur L., Quercus pyrenaica Willd., Pinus sylvestris L. and Pinus pinaster Ait.). The lowest photochemical efficiency (F(v)/F(m) in dark-adapted leaves) was reached in deep shade (1% of full sunlight) in all species except Q. robur, which had the lowest photochemical efficiency in both deep shade and 100% of full sunlight. Species differed significantly in their survival in 1% of full sunlight but exhibited similar survivorship in 6, 20 and 100% of full sunlight. Shade-tolerant oaks had lower leaf area ratios, shoot to root ratios, foliage allocation ratios and higher rates of allocation to structural biomass (stem plus thick roots) than shade-intolerant pines. Overall phenotypic plasticity for each species, estimated as the difference between the minimum and the maximum mean values of the ecophysiological variables studied at the various irradiances divided by the maximum mean value of those variables, was inversely correlated with shade tolerance. Observed morphology, allocation and plasticity conformed to a conservative resource-use strategy, although observed differences in specific leaf area, which was higher in shade-tolerant species, supported a carbon gain maximization strategy. Lack of a congruent suite of traits underlying shade tolerance in the studied species provides evidence of adaptation to multiple selective forces. Although the study was based on only four species, the importance of ecophysiological variables as determinants of interspecific differences in survival in limiting light was demonstrated.
Influence of habitat and intrinsic characteristics on survival of neonatal pronghorn
Jacques, Christopher N.; Jenks, Jonathan A.; Grovenburg, Troy W.; Klaver, Robert W.
2015-01-01
Increased understanding of the influence of habitat (e.g., composition, patch size) and intrinsic (e.g., age, birth mass) factors on survival of neonatal pronghorn (Antilocapra americana) is a prerequisite to successful management programs, particularly as they relate to population dynamics and the role of population models in adaptive species management. Nevertheless, few studies have presented empirical data quantifying the influence of habitat variables on survival of neonatal pronghorn. During 2002–2005, we captured and radiocollared 116 neonates across two sites in western South Dakota. We documented 31 deaths during our study, of which coyote (Canis latrans) predation (n = 15) was the leading cause of mortality. We used known fate analysis in Program MARK to investigate the influence of intrinsic and habitat variables on neonatal survival. We generated a priori models that we grouped into habitat and intrinsic effects. The highest-ranking model indicated that neonate mortality was best explained by site, percent grassland, and open water habitat; 90-day survival (0.80; 90% CI = 0.71–0.88) declined 23% when grassland and water increased from 80.1 to 92.3% and 0.36 to 0.40%, respectively, across 50% natal home ranges. Further, our results indicated that grassland patch size and shrub density were important predictors of neonate survival; neonate survival declined 17% when shrub density declined from 5.0 to 2.5 patches per 100 ha. Excluding the site covariates, intrinsic factors (i.e., sex, age, birth mass, year, parturition date) were not important predictors of survival of neonatal pronghorns. Further, neonatal survival may depend on available land cover and interspersion of habitats. We have demonstrated that maintaining minimum and maximum thresholds for habitat factors (e.g., percentages of grassland and open water patches, density of shrub patches) throughout natal home ranges will in turn, ensure relatively high (>0.50) neonatal survival rates, especially as they relate to coyote predation. Thus, landscape level variables (particularly percentages of open water, grassland habitats, and shrub density) should be incorporated into the development or implementation of pronghorn management plans across sagebrush steppe communities of the western Dakotas, and potentially elsewhere within the geographic range of pronghorn.
Liebezeit, J R; Kendall, S J; Brown, S; Johnson, C B; Martin, P; McDonald, T L; Payer, D C; Rea, C L; Streever, B; Wildman, A M; Zack, S
2009-09-01
Nest predation may influence population dynamics of birds on the Arctic Coastal Plain (ACP) of Alaska, USA. Anthropogenic development on the ACP is increasing, which may attract nest predators by providing artificial sources of food, perches, den sites, and nest sites. Enhanced populations or concentrations of human-subsidized predators may reduce nest survival for tundra-nesting birds. In this study, we tested the hypothesis that nest survival decreases in proximity to human infrastructure. We monitored 1257 nests of 13 shorebird species and 619 nests of four passerine species at seven sites on the ACP from 2002 to 2005. Study sites were chosen to represent a range of distances to infrastructure from 100 m to 80 km. We used Cox proportional hazards regression models to evaluate the effects of background (i.e., natural) factors and infrastructure on nest survival. We documented high spatial and temporal variability in nest survival, and site and year were both included in the best background model. We did not detect an effect of human infrastructure on nest survival for shorebirds as a group. In contrast, we found evidence that risk of predation for passerine nests increased within 5 km of infrastructure. This finding provides quantitative evidence of a relationship between infrastructure and nest survival for breeding passerines on the ACP. A posteriori finer-scale analyses (within oil field sites and individual species) suggested that Red and Red-necked Phalaropes combined (Phalaropus fulicarius, P. lobatus) had lower productivity closer to infrastructure and in areas with higher abundance of subsidized predators. However, we did not detect such a relationship between infrastructure and nest survival for Semipalmated and Pectoral Sandpipers (Calidris pusilla, C. melanotos), the two most abundant shorebirds. High variability in environmental conditions, nest survival, and predator numbers between sites and years may have contributed to these inconsistent results. We recommend targeted management actions to minimize anthropogenic effects and suggest new research needed on this issue as expanding development is planned for the ACP of Alaska. In particular, we recommend research on demography of key predators and their importance with respect to nest survival, and experimental studies that better address challenges posed by high natural variability.
Aubry, Lise M; Cam, Emmanuelle; Koons, David N; Monnat, Jean-Yves; Pavard, Samuel
2011-03-01
1. We assessed the relative influence of variability in recruitment age, dynamic reproductive investment (time-specific reproductive states) and frailty (unobserved differences in survival abilities across individuals) on survival in the black-legged kittiwake. Furthermore, we examined whether observed variability in survival trajectories was best explained by immediate reproductive investment, cumulative investment, or both. 2. Individuals that delayed recruitment (≥ age 7) suffered a higher mortality risk than early recruits (age 3), especially later in life, suggesting that recruitment age may be an indicator of individual quality. Although recruitment age helped explain variation in survival, time-varying reproductive investment had a more substantial influence. 3. The dichotomy of attempting to breed or not explained variability in survival across life better than other parameterizations of reproductive states such as clutch size, brood size or breeding success. In the kittiwake, the sinequanon condition to initiate reproduction is to hold a nest site, which is considered a very competitive activity. This might explain why attempting to breed is the key level of investment that affects survival, independent of the outcome (failure or success). 4. Interestingly, the more individuals cumulate reproductive attempts over life, the lower their mortality risk, indicating that breeding experience may be a good indicator of parental quality as well. In contrast, attempting to breed at time t increased the risk of mortality between t and t + 1. We thus detected an immediate trade-off between attempting to breed and survival in this population; however, the earlier individuals recruited, and the more breeding experience they accumulated, the smaller the cost. 5. Lastly, unobserved heterogeneity across individuals improved model fit more (1·3 times) than fixed and dynamic sources of observed heterogeneity in reproductive investment, demonstrating that it is critical to account for both sources of individual heterogeneity when studying survival trajectories. Only after simultaneously accounting for both sources of heterogeneity were we able to detect the 'cost' of immediate reproductive investment on survival and the 'benefit' of cumulative breeding attempts (experience), a proxy to individual quality. © 2010 The Authors. Journal of Animal Ecology © 2010 British Ecological Society.
Local Variability Mediates Vulnerability of Trout Populations to Land Use and Climate Change
Penaluna, Brooke E.; Dunham, Jason B.; Railsback, Steve F.; Arismendi, Ivan; Johnson, Sherri L.; Bilby, Robert E.; Safeeq, Mohammad; Skaugset, Arne E.
2015-01-01
Land use and climate change occur simultaneously around the globe. Fully understanding their separate and combined effects requires a mechanistic understanding at the local scale where their effects are ultimately realized. Here we applied an individual-based model of fish population dynamics to evaluate the role of local stream variability in modifying responses of Coastal Cutthroat Trout (Oncorhynchus clarkii clarkii) to scenarios simulating identical changes in temperature and stream flows linked to forest harvest, climate change, and their combined effects over six decades. We parameterized the model for four neighboring streams located in a forested headwater catchment in northwestern Oregon, USA with multi-year, daily measurements of stream temperature, flow, and turbidity (2007–2011), and field measurements of both instream habitat structure and three years of annual trout population estimates. Model simulations revealed that variability in habitat conditions among streams (depth, available habitat) mediated the effects of forest harvest and climate change. Net effects for most simulated trout responses were different from or less than the sum of their separate scenarios. In some cases, forest harvest countered the effects of climate change through increased summer flow. Climate change most strongly influenced trout (earlier fry emergence, reductions in biomass of older trout, increased biomass of young-of-year), but these changes did not consistently translate into reductions in biomass over time. Forest harvest, in contrast, produced fewer and less consistent responses in trout. Earlier fry emergence driven by climate change was the most consistent simulated response, whereas survival, growth, and biomass were inconsistent. Overall our findings indicate a host of local processes can strongly influence how populations respond to broad scale effects of land use and climate change. PMID:26295478
Local variability mediates vulnerability of trout populations to land use and climate change
Penaluna, Brooke E.; Dunham, Jason B.; Railsback, Steve F.; Arismendi, Ivan; Johnson, Sherri L.; Bilby, Robert E; Safeeq, Mohammad; Skaugset, Arne E.
2015-01-01
Land use and climate change occur simultaneously around the globe. Fully understanding their separate and combined effects requires a mechanistic understanding at the local scale where their effects are ultimately realized. Here we applied an individual-based model of fish population dynamics to evaluate the role of local stream variability in modifying responses of Coastal Cutthroat Trout (Oncorhynchus clarkii clarkii) to scenarios simulating identical changes in temperature and stream flows linked to forest harvest, climate change, and their combined effects over six decades. We parameterized the model for four neighboring streams located in a forested headwater catchment in northwestern Oregon, USA with multi-year, daily measurements of stream temperature, flow, and turbidity (2007–2011), and field measurements of both instream habitat structure and three years of annual trout population estimates. Model simulations revealed that variability in habitat conditions among streams (depth, available habitat) mediated the effects of forest harvest and climate change. Net effects for most simulated trout responses were different from or less than the sum of their separate scenarios. In some cases, forest harvest countered the effects of climate change through increased summer flow. Climate change most strongly influenced trout (earlier fry emergence, reductions in biomass of older trout, increased biomass of young-of-year), but these changes did not consistently translate into reductions in biomass over time. Forest harvest, in contrast, produced fewer and less consistent responses in trout. Earlier fry emergence driven by climate change was the most consistent simulated response, whereas survival, growth, and biomass were inconsistent. Overall our findings indicate a host of local processes can strongly influence how populations respond to broad scale effects of land use and climate change.
Local Variability Mediates Vulnerability of Trout Populations to Land Use and Climate Change.
Penaluna, Brooke E; Dunham, Jason B; Railsback, Steve F; Arismendi, Ivan; Johnson, Sherri L; Bilby, Robert E; Safeeq, Mohammad; Skaugset, Arne E
2015-01-01
Land use and climate change occur simultaneously around the globe. Fully understanding their separate and combined effects requires a mechanistic understanding at the local scale where their effects are ultimately realized. Here we applied an individual-based model of fish population dynamics to evaluate the role of local stream variability in modifying responses of Coastal Cutthroat Trout (Oncorhynchus clarkii clarkii) to scenarios simulating identical changes in temperature and stream flows linked to forest harvest, climate change, and their combined effects over six decades. We parameterized the model for four neighboring streams located in a forested headwater catchment in northwestern Oregon, USA with multi-year, daily measurements of stream temperature, flow, and turbidity (2007-2011), and field measurements of both instream habitat structure and three years of annual trout population estimates. Model simulations revealed that variability in habitat conditions among streams (depth, available habitat) mediated the effects of forest harvest and climate change. Net effects for most simulated trout responses were different from or less than the sum of their separate scenarios. In some cases, forest harvest countered the effects of climate change through increased summer flow. Climate change most strongly influenced trout (earlier fry emergence, reductions in biomass of older trout, increased biomass of young-of-year), but these changes did not consistently translate into reductions in biomass over time. Forest harvest, in contrast, produced fewer and less consistent responses in trout. Earlier fry emergence driven by climate change was the most consistent simulated response, whereas survival, growth, and biomass were inconsistent. Overall our findings indicate a host of local processes can strongly influence how populations respond to broad scale effects of land use and climate change.
Prognostic indicators for dogs with dilated cardiomyopathy.
Borgarelli, Michele; Santilli, Roberto A; Chiavegato, David; D'Agnolo, Gino; Zanatta, Renato; Mannelli, Alessandro; Tarducci, Alberto
2006-01-01
The purpose of this study was to investigate the prognostic value of various clinical, ECG, echocardiographic, and Doppler echocardiographic variables in dogs with dilated cardiomyopathy. The relationship to survival of 11 variables was evaluated in 63 dogs. Studied variables were age at time of diagnosis, class of heart failure (HF), dyspnea, ascites, atrial fibrillation (AF), ejection fraction (EF), E-point septal separation, end-diastolic volume index, end-systolic volume index (ESV-I), and restrictive or nonrestrictive transmitral flow (TMF) pattern. Median survival time was 671 days (lower 95% confidence limit, 350 days). Survival curves showed that severity of HF, ascites, ESV-I greater than 140 mL/m2, EF less than 25%, and restrictive TMF pattern had a significant negative relation to survival time. Thirty-nine dogs with both sinus rhythm and AF presented adequate TMF recordings; in these dogs, after stratification by TMF pattern, the restrictive TMF pattern was the most important negative prognostic indicator. We conclude that in dogs with dilated cardiomyopathy the restrictive TMF pattern appears to represent a useful prognostic indicator. Class of HF, ascites, ESV-I, and EF are also useful indexes if an adequate TMF pattern is not recorded.
Blum Murphy, Mariela; Xiao, Lianchum; Patel, Viren R; Maru, Dipen M; Correa, Arlene M; G Amlashi, Fatemeh; Liao, Zhongxing; Komaki, Ritsuko; Lin, Steven H; Skinner, Heath D; Vaporciyan, Ara; Walsh, Garrett L; Swisher, Stephen G; Sepesi, Boris; Lee, Jeffrey H; Bhutani, Manoop S; Weston, Brian; Hofstetter, Wayne L; Ajani, Jaffer A
2017-11-01
Reports are limited regarding clinical and pretreatment features that might predict a pathological complete response (pathCR) after treatment in patients with esophageal cancer (EC). This might allow patient selection for different strategies. This study examines the association of a pathCR with pretreatment variables, overall survival (OS), recurrence-free survival (RFS), and patterns of recurrence in a large cohort from a single institution. The baseline clinical features of 911 consecutive patients with EC who were treated with trimodality therapy from January 2000 to November 2013 were analyzed. A pathCR was defined as a surgical specimen with no residual carcinoma (primary or nodes). Logistic regressions were used to identify independent baseline features associated with a pathCR. We applied log-rank testing and Cox models to determine the association between a pathCR and the time-to-event outcomes (OS and RFS). Of 911 patients, 218 (23.9%) achieved a pathCR. The pathCR rate was 23.1% for adenocarcinoma and 32.2% for squamous cell carcinoma. A lower pathCR rate was observed for 1) older patients (>60 years), 2) patients with poorly differentiated tumors, 3) patients with signet ring cells (SRCs), and 4) patients with a higher T stage. Patients with a pathCR had longer OS and RFS than those without a pathCR (P = .0021 and P = .0011, respectively). Recurrences occurred more in non-pathCR patients. Distant metastases were the most common type of recurrence. PathCR patients developed brain metastases at a marginally higher rate than non-pathCR patients (P = .051). In this large cohort study, a pathCR is confirmed to be associated with better OS and RFS. The presence of a poorly differentiated tumor or SRCs reduces the likelihood of a pathCR. Future research should focus on molecular classifiers. Cancer 2017;123:4106-4113. © 2017 American Cancer Society. © 2017 American Cancer Society.
De Santis, R J; Poon, I; Lee, J; Karam, I; Enepekides, D J; Higgins, K M
2016-08-02
The literature reports various treatment methodologies, such as trans-oral laser microsurgery, radiation therapy, total/partial laryngectomies, and concurrent radiation chemotherapy for patients with early larynx cancer. However, at the forefront of early glottis treatment is trans-oral laser microsurgery and radiation therapy, likely due to better functional and survival outcomes. Here we conduct the largest Canadian head-to-head comparison of consecutive patients treated with either radiation therapy or trans-oral laser microsurgery. Additionally, we compare these two treatments and their 5-year survival rates post treatment to add to the existing literature. Charts of patients who were diagnosed with early glottic cancer between 2006 and 2013 were reviewed. Seventy-five patients were identified, and split into 2 groups based on their primary treatment, trans-oral laser microsurgery and radiation therapy. Kaplan-Meier survival curves, life-tables, and the log-rank statistic were reported to determine if there was a difference between the two treatment groups and their disease-specific survival, disease-free survival, and total laryngectomy-free survival. Additionally, each different survival analysis was stratified by potential confounding variables, to help conclude which treatment is more efficacious in this population. The 5-year disease-specific survival rate is 93.3 % σ = 0.063 and 90.8 % σ = 0.056 for patients treated with trans-oral laser microsurgery and radiation therapy, respectively (χ (2) < 0.001, p = 0.983). The disease free survival rate is 60.0 % (σ =0.121) for patients treated with trans-oral laser microsurgery, and 67.2 % (σ = 0.074) for those who received RT (χ (2) = 0.19, p = 0.663). Additionally, the total laryngectomy-free survival rate is 84.1 % (σ = 0.1) and 79.1 % (σ = 0.072) for patients' early glottic cancer treated by trans-oral laser microsurgery and radiation therapy, respectively (χ (2) = 0.235, p = 0.628). Chi-square analysis of age-group versus treatment group (χ (2) = 6.455, p = 0.04) and T-stage versus treatment group (χ (2) = 11.3, p = 0.001) revealed a statistically significant relationship, suggesting survival analysis should be stratified by these variables. However, after stratification, there was no statistically significant difference between the trans-oral laser microsurgery and radiation therapy groups in any of the survival analyses. No difference was demonstrated in the 5-year disease-specific survival, disease-free survival, and total laryngectomy-free survival, between the RT and TLM treatment groups. Additionally, both groups showed similar 5-year survival after stratifying by confounding variables.
Mainou, Maria; Madenidou, Anastasia-Vasiliki; Liakos, Aris; Paschos, Paschalis; Karagiannis, Thomas; Bekiari, Eleni; Vlachaki, Efthymia; Wang, Zhen; Murad, Mohammad Hassan; Kumar, Shaji; Tsapas, Apostolos
2017-06-01
We performed a systematic review and meta-regression analysis of randomized control trials to investigate the association between response to initial treatment and survival outcomes in patients with newly diagnosed multiple myeloma (MM). Response outcomes included complete response (CR) and the combined outcome of CR or very good partial response (VGPR), while survival outcomes were overall survival (OS) and progression-free survival (PFS). We used random-effect meta-regression models and conducted sensitivity analyses based on definition of CR and study quality. Seventy-two trials were included in the systematic review, 63 of which contributed data in meta-regression analyses. There was no association between OS and CR in patients without autologous stem cell transplant (ASCT) (regression coefficient: .02, 95% confidence interval [CI] -0.06, 0.10), in patients undergoing ASCT (-.11, 95% CI -0.44, 0.22) and in trials comparing ASCT with non-ASCT patients (.04, 95% CI -0.29, 0.38). Similarly, OS did not correlate with the combined metric of CR or VGPR, and no association was evident between response outcomes and PFS. Sensitivity analyses yielded similar results. This meta-regression analysis suggests that there is no association between conventional response outcomes and survival in patients with newly diagnosed MM. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Yang, Hao-Jie; Jiang, Jing-Hang; Yang, Yu-Ting; Guo, Zhe; Li, Ji-Jia; Liu, Xuan-Han; Lu, Fei; Zeng, Feng-Hua; Ye, Jin-Song; Zhang, Ke-Lan; Chen, Neng-Zhi; Xiang, Bang-De; Li, Le-Qun
2017-03-01
The aspartate aminotransferase-to-platelet ratio index has been reported to predict prognosis of patients with hepatocellular carcinoma. This study examined the prognostic potential of stratified aspartate aminotransferase-to-platelet ratio index for hepatocellular carcinoma patients undergoing curative liver resection. A total of 661 hepatocellular carcinoma patients were retrieved and the associations between aspartate aminotransferase-to-platelet ratio index and clinicopathological variables and survivals (overall survival and disease-free survival) were analyzed. Higher aspartate aminotransferase-to-platelet ratio index quartiles were significantly associated with poorer overall survival (p = 0.002) and disease-free survival (p = 0.001). Multivariate analysis showed aspartate aminotransferase-to-platelet ratio index to be an independent risk factor for overall survival (p = 0.018) and disease-free survival (p = 0.01). Patients in the highest aspartate aminotransferase-to-platelet ratio index quartile were at 44% greater risk of death than patients in the first quartile (hazard ratio = 1.445, 95% confidence interval = 1.081 - 1.931, p = 0.013), as well as 49% greater risk of recurrence (hazard ratio = 1.49, 95% confidence interval = 1.112-1.998, p = 0.008). Subgroup analysis also showed aspartate aminotransferase-to-platelet ratio index to be an independent predictor of poor overall survival and disease-free survival in patients positive for hepatitis B surface antigen or with cirrhosis (both p < 0.05). Similar results were obtained when aspartate aminotransferase-to-platelet ratio index was analyzed as a dichotomous variable with cutoff values of 0.25 and 0.62. Elevated preoperative aspartate aminotransferase-to-platelet ratio index may be independently associated with poor overall survival and disease-free survival in hepatocellular carcinoma patients following curative resection.
A multi-year analysis of passage and survival at McNary Dam, 2004-09
Adams, Noah S.; Walker, C.E.; Perry, R.W.
2011-01-01
We analyzed 6 years (2004–09) of passage and survival data collected at McNary Dam to determine how dam operations and environmental conditions affect passage and survival of juvenile salmonids. A multinomial logistic regression was used to examine how environmental variables and dam operations relate to passage behavior of juvenile salmonids at McNary Dam. We used the Cormack-Jolly-Seber release-recapture model to determine how the survival of juvenile salmonids passing through McNary Dam relates to environmental variables and dam operations. Total project discharge and the proportion of flow passing the spillway typically had a positive effect on survival for all species and routes. As the proportion of water through the spillway increased, the number of fish passing the spillway increased, as did overall survival. Additionally, survival generally was higher at night. There was no meaningful difference in survival for fish that passed through the north or south portions of the spillway or powerhouse. Similarly, there was no difference in survival for fish released in the north, middle, or south portions of the tailrace. For subyearling Chinook salmon migrating during the summer season, increased temperatures had a drastic effect on passage and survival. As temperature increased, survival of subyearling Chinook salmon decreased through all passage routes and the number of fish that passed through the turbines increased. During years when the temporary spillway weirs (TSWs) were installed, passage through the spillway increased for spring migrants. However, due to the changes made in the location of the TSW between years and the potential effect of other confounding environmental conditions, it is not certain if the increase in spillway passage was due solely to the presence of the TSWs. The TSWs appeared to improve forebay survival during years when they were operated.
Survival estimates for Florida manatees from the photo-identification of individuals
Langtimm, C.A.; Beck, C.A.; Edwards, H.H.; Fick-Child, K. J.; Ackerman, B.B.; Barton, S.L.; Hartley, W.C.
2004-01-01
We estimated adult survival probabilities for the endangered Florida manatee (Trichechus manatus latirostris) in four regional populations using photo-identification data and open-population capture-recapture statistical models. The mean annual adult survival probability over the most recent 10-yr period of available estimates was as follows: Northwest - 0.956 (SE 0.007), Upper St. Johns River - 0.960 (0.011), Atlantic Coast - 0.937 (0.008), and Southwest - 0.908 (0.019). Estimates of temporal variance independent of sampling error, calculated from the survival estimates, indicated constant survival in the Upper St. Johns River, true temporal variability in the Northwest and Atlantic Coast, and large sampling variability obscuring estimates for the Southwest. Calf and subadult survival probabilities were estimated for the Upper St. Johns River from the only available data for known-aged individuals: 0.810 (95% CI 0.727-0.873) for 1st year calves, 0.915 (0.827-0.960) for 2nd year calves, and 0.969 (0.946-0.982) for manatee 3 yr or older. These estimates of survival probabilities and temporal variance, in conjunction with estimates of reproduction probabilities from photoidentification data can be used to model manatee population dynamics, estimate population growth rates, and provide an integrated measure of regional status.
Janssen, Stefan; Hansen, Heinke C; Schild, Steven E; Rades, Dirk
2018-06-01
Patients with cerebral metastases from gynecological cancer who receive whole-brain irradiation (WBI) alone require personalized therapy. This study contributes to personalized care by creating an instrument to predict 6-month survival probability. In 49 patients, six pre-treatment variables, namely age, Eastern Cooperative Oncology Group performance score (ECOG-PS), primary tumor type, number of cerebral metastases, metastasis outside the brain, and interval between diagnosis of gynecological cancer and WBI, were analyzed for survival. Of the six pre-treatment variables, ECOG-PS was significantly associated with survival (p=0.014) and metastasis outside the brain showed a trend for association (p=0.096). Six-month survival rates divided by 10 resulted in scores of 0, 2 or 7 points for ECOG-PS and of 2 or 7 points for metastasis outside the brain. Scores for individual patients were 2, 4, 7, 9 or 14 points. Three groups were created, those with 2-7, 9 and 14 points, with 6-month survival rates of 10%, 53% and 100%, respectively (p=0.004). An instrument was designed to predict the 6-month survival of patients receiving WBI for cerebral metastases from gynecological cancer and facilitate personalized care. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.
Kato, Takao; Pezzella, Francesco; Steers, Graham; Campo, Leticia; Leek, Russell D; Turley, Helen; Kameoka, Shingo; Nishikawa, Toshio; Harris, Adrian L; Gatter, Kevin C; Fox, Stephen
2014-01-01
This study was undertaken to investigate the associations of blood vessel invasion (BVI), lymphatic vessel invasion (LVI) or other variables and long-term survival in 173 Japanese and 184 British patients with primary invasive breast cancer, and whether they are associated with survival differences between Japanese and British patients. BVI was detected by objective methods, using both factor VIII-related antigen (F-VIII) staining and elastica van Gieson (E v G) staining. BVI was classified into three subtypes. 1) BVI e, BVI detected by E v G staining alone, 2) BVI f, BVI detected by F-VIII staining alone, 3) BVIef, BVI evaluated by combining BVIf and BVIe. LVI was also detected by objective methods, using lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1) staining alone. There was a borderline significance between the frequencies for BVIef of British patients and those of Japanese patients (8.2% vs 3.5%; P = 0.06) but not for LVI (P = 0.36). British patients had a significantly worse relapse-free survival (RFS) and overall survival (OS) than Japanese patients (P < 0.01, P < 0.01, respectively) even though their tumors were smaller and more ER-positive with a similar prevalence of lymph-node involvement. LVI was not significantly associated with RFS and OS, however, BVIef positive tumors had a significantly worse RFS and OS compared with BVIef negative patients, after statistical adjustment for the other variables (P = 0.02, P = 0.01, respectively). The present study shows that BVIef variability might contribute to the Japanese and British disparities in breast cancer outcomes. PMID:25550840
Bygren, L O; Konlaan, B B; Johansson, S E
To investigate the possible influence of attendance at cultural events, reading books or periodicals, making music or singing in a choir as determinants for survival. A simple random sample was drawn of 15,198 individuals aged 16-74 years. Of these, 85% (12,982) were interviewed by trained non-medical interviewers between 1982 and 1983 about cultural activities. They were followed up with respect to survival until 31 December 1991. Swedish interview survey of living conditions comprising a random sample of the adult Swedish population. 12,675 people interviewed between 1982 and 1983. Survival of subjects after controlling for eight confounding variables: age, sex, education level, income, long term disease, social network, smoking, and physical exercise. 6,301 men and 6,374 women were followed up; 533 men and 314 women died during this period. The control variables influenced survival in the expected directions except for social network for men; a significant negative effective was found when the analysis was made separately for men and women. We found an influence on mortality when the eight control variables were controlled for in people who rarely attended events compared with those attending most often, the relative risk being 1.57 (95% confidence interval 1.18 to 2.09). Attendance at cultural events may have a positive influence on survival. Long term follow up of large samples with confounders that are well controlled for and with the cultural stimulation more highly specified should be used to try to falsify the hypothesis before experiments start.
Ten-year results of a ponderosa pine progeny test in the Black Hills
Wayne D. Shepperd; Sue E. McElderry
1986-01-01
Ten-year survival and growth of seedlings from 77 parent trees from throughout the Black Hills were compared, using a cluster-analysis technique. Five clusters were identified that account for most of the variability in survival and growth of the open-pollinated families. One cluster, containing 6 families, exhibited exceptional survival and growth. Another, containing...
Shear, Katherine; Newth, Christopher J.L.; Harrison, Rick; Berger, John; Zimmerman, Jerry; Anand, K.J.S.; Carcillo, Joseph; Donaldson, Amy E.; Dean, J. Michael; Willson, Douglas F.; Nicholson, Carol
2011-01-01
Abstract Objective We previously demonstrated that parents whose children die in a pediatric intensive care unit (PICU) have a high level of complicated grief symptoms 6 months after the death. In this study, we investigate the change in the extent of complicated grief symptoms among these parents between 6 and 18 months postdeath and identify factors predicting improvement. Methods One hundred thirty-eight parents of 106 children completed surveys at 6 and 18 months. Surveys included the Inventory of Complicated Grief (ICG), measures of grief avoidance, attachment, caregiving and social support, and demographics. Multivariable analysis was performed using generalized estimating equations to identify characteristics independently associated with improvement in ICG score. Results ICG scores were 33.4 ± 13.6 at 6 months and 28.0 ± 13.5 at 18 months, representing an improvement in ICG score of 5.4 + 8.0 (95% confidence interval [CI] 4.1–6.8, p < 0.001). Variables independently associated with greater improvement in ICG score included traumatic death and greater grief avoidance. Variables independently associated with less improvement included being the biological parent and having more responsive caregiving. Parents with one or two surviving children had more improvement in ICG score than those with no surviving children whereas parents with three or more surviving children had less improvement. Conclusion Complicated grief symptoms decrease among parents between 6 and 18 months after their child's death in the PICU; however, high symptom levels persists for some. Better understanding of the trajectory of complicated grief will allow parents at risk for persistent distress to receive professional support. PMID:21281122
Ballesteros, Daniel; Sershen; Varghese, Boby; Berjak, Patricia; Pammenter, Norman W
2014-08-01
Cryopreservation is the most promising option for the long-term germplasm conservation of recalcitrant-seeded species. However, the variable post-cryo success achieved with the excised zygotic explants traditionally used for cryopreservation has been a concern for some time. Differential drying rates amongst explants of different species, uneven drying amongst explants within a batch of seeds and uneven drying across tissues within individual embryos could be contributory factors to this variable success and these phenomena form the foci of the present study. Using zygotic explants from a range of recalcitrant-seeded species, which included sub-tropical dicotyledonous trees and sub-tropical monocotyledonous geophytes, the study showed that embryo morphology and anatomy are critical determinants of the drying characteristics of the different tissues composing the explant and hence, post-cryo survival. The results suggest that the rates of drying of explants to water contents (WCs) in the theoretically optimal range for successful cryopreservation are species-specific, and that more rapid drying rates may promote post-cryo survival. However, the large variation in WC amongst individual explants in bulk samples challenges the selection of the theoretically optimum WC for cryopreservation. As a consequence of differential drying rates across the different tissues composing explants, either lethal ice crystal damage or desiccation damage may sometimes be likely in tissues responsible for the onwards development of the embryo. Drying times for cryopreservation of such explants should, therefore, be selected on the basis of WC of segments containing root or shoot meristem, rather than embryo bulk WC. Drying intensity and duration also interact with explant morphology and embryo/axis size and anatomy to bring about - or preclude - post-cryo survival. Copyright © 2014 Elsevier Inc. All rights reserved.
Survival analysis of cervical cancer using stratified Cox regression
NASA Astrophysics Data System (ADS)
Purnami, S. W.; Inayati, K. D.; Sari, N. W. Wulan; Chosuvivatwong, V.; Sriplung, H.
2016-04-01
Cervical cancer is one of the mostly widely cancer cause of the women death in the world including Indonesia. Most cervical cancer patients come to the hospital already in an advanced stadium. As a result, the treatment of cervical cancer becomes more difficult and even can increase the death's risk. One of parameter that can be used to assess successfully of treatment is the probability of survival. This study raises the issue of cervical cancer survival patients at Dr. Soetomo Hospital using stratified Cox regression based on six factors such as age, stadium, treatment initiation, companion disease, complication, and anemia. Stratified Cox model is used because there is one independent variable that does not satisfy the proportional hazards assumption that is stadium. The results of the stratified Cox model show that the complication variable is significant factor which influent survival probability of cervical cancer patient. The obtained hazard ratio is 7.35. It means that cervical cancer patient who has complication is at risk of dying 7.35 times greater than patient who did not has complication. While the adjusted survival curves showed that stadium IV had the lowest probability of survival.
Drought responses of flood-tolerant trees in Amazonian floodplains
Parolin, Pia; Lucas, Christine; Piedade, Maria Teresa F.; Wittmann, Florian
2010-01-01
Background Flood-tolerant tree species of the Amazonian floodplain forests are subjected to an annual dry period of variable severity imposed when low river-water levels coincide with minimal precipitation. Although the responses of these species to flooding have been examined extensively, their responses to drought, in terms of phenology, growth and physiology, have been neglected hitherto, although some information is found in publications that focus on flooding. Scope The present review examines the dry phase of the annual flooding cycle. It consolidates existing knowledge regarding responses to drought among adult trees and seedlings of many Amazonian floodplain species. Main Findings Flood-tolerant species display variable physiological responses to dry periods and drought that indicate desiccation avoidance, such as reduced photosynthetic activity and reduced root respiration. However, tolerance and avoidance strategies for drought vary markedly among species. Drought can substantially decrease growth, biomass and photosynthetic activity among seedlings in field and laboratory studies. When compared with the responses to flooding, drought can impose higher seedling mortality and slower growth rates, especially among evergreen species. Results indicate that tolerance and avoidance strategies for drought vary markedly between species. Both seedling recruitment and photosynthetic activity are affected by drought, Conclusions For many species, the effects of drought can be as important as flooding for survival and growth, particularly at the seedling phase of establishment, ultimately influencing species composition. In the context of climate change and predicted decreases in precipitation in the Amazon Basin, the effects of drought on plant physiology and species distribution in tropical floodplain forest ecosystems should not be overlooked. PMID:19880423
Ahmed, Haitham M; Al-Mallah, Mouaz H; McEvoy, John W; Nasir, Khurram; Blumenthal, Roger S; Jones, Steven R; Brawner, Clinton A; Keteyian, Steven J; Blaha, Michael J
2015-03-01
To determine which routinely collected exercise test variables most strongly correlate with survival and to derive a fitness risk score that can be used to predict 10-year survival. This was a retrospective cohort study of 58,020 adults aged 18 to 96 years who were free of established heart disease and were referred for an exercise stress test from January 1, 1991, through May 31, 2009. Demographic, clinical, exercise, and mortality data were collected on all patients as part of the Henry Ford ExercIse Testing (FIT) Project. Cox proportional hazards models were used to identify exercise test variables most predictive of survival. A "FIT Treadmill Score" was then derived from the β coefficients of the model with the highest survival discrimination. The median age of the 58,020 participants was 53 years (interquartile range, 45-62 years), and 28,201 (49%) were female. Over a median of 10 years (interquartile range, 8-14 years), 6456 patients (11%) died. After age and sex, peak metabolic equivalents of task and percentage of maximum predicted heart rate achieved were most highly predictive of survival (P<.001). Subsequent addition of baseline blood pressure and heart rate, change in vital signs, double product, and risk factor data did not further improve survival discrimination. The FIT Treadmill Score, calculated as [percentage of maximum predicted heart rate + 12(metabolic equivalents of task) - 4(age) + 43 if female], ranged from -200 to 200 across the cohort, was near normally distributed, and was found to be highly predictive of 10-year survival (Harrell C statistic, 0.811). The FIT Treadmill Score is easily attainable from any standard exercise test and translates basic treadmill performance measures into a fitness-related mortality risk score. The FIT Treadmill Score should be validated in external populations. Copyright © 2015 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.
Geographic variation in the response of Culex pipiens life history traits to temperature.
Ruybal, Jordan E; Kramer, Laura D; Kilpatrick, A Marm
2016-02-29
Climate change is predicted to alter the transmission of many vector-borne pathogens. The quantitative impact of climate change is usually estimated by measuring the temperature-performance relationships for a single population of vectors, and then mapping this relationship across a range of temperatures or locations. However, life history traits of different populations often differ significantly. Specifically, performance across a range of temperatures is likely to vary due to local adaptation to temperature and other factors. This variation can cause spatial variation in pathogen transmission and will influence the impact of climate change on the transmission of vector-borne pathogens. We quantified variation in life history traits for four populations of Culex pipiens (Linnaeus) mosquitoes. The populations were distributed along altitudinal and latitudinal gradients in the eastern United States that spanned ~3 °C in mean summer temperature, which is similar to the magnitude of global warming expected in the next 3-5 decades. We measured larval and adult survival, development rate, and biting rate at six temperatures between 16 and 35 °C, in a common garden experiment. Temperature had strong and consistent non-linear effects on all four life history traits for all four populations. Adult female development time decreased monotonically with increasing temperature, with the largest decrease at cold temperatures. Daily juvenile and adult female survival also decreased with increasing temperature, but the largest decrease occurred at higher temperatures. There was significant among-population variation in the thermal response curves for the four life history traits across the four populations, with larval survival, adult survival, and development rate varying up to 45, 79, and 84 % among populations, respectively. However, variation was not correlated with local temperatures and thus did not support the local thermal adaptation hypothesis. These results suggest that the impact of climate change on vector-borne disease will be more variable than previous predictions, and our data provide an estimate of this uncertainty. In addition, the variation among populations that we observed will shape the response of vectors to changing climates.
RNA-Mediated cis Regulation in Acinetobacter baumannii Modulates Stress-Induced Phenotypic Variation
Ching, Carly; Gozzi, Kevin; Heinemann, Björn; Chai, Yunrong
2017-01-01
ABSTRACT In the nosocomial opportunistic pathogen Acinetobacter baumannii, RecA-dependent mutagenesis, which causes antibiotic resistance acquisition, is linked to the DNA damage response (DDR). Notably, unlike the Escherichia coli paradigm, recA and DDR gene expression in A. baumannii is bimodal. Namely, there is phenotypic variation upon DNA damage, which may provide a bet-hedging strategy for survival. Thus, understanding recA gene regulation is key to elucidate the yet unknown DDR regulation in A. baumannii. Here, we identify a structured 5′ untranslated region (UTR) in the recA transcript which serves as a cis-regulatory element. We show that a predicted stem-loop structure in this 5′ UTR affects mRNA half-life and underlies bimodal gene expression and thus phenotypic variation in response to ciprofloxacin treatment. We furthermore show that the stem-loop structure of the recA 5′ UTR influences intracellular RecA protein levels and, in vivo, impairing the formation of the stem-loop structure of the recA 5′ UTR lowers cell survival of UV treatment and decreases rifampin resistance acquisition from DNA damage-induced mutagenesis. We hypothesize that the 5′ UTR allows for stable recA transcripts during stress, including antibiotic treatment, enabling cells to maintain suitable RecA levels for survival. This innovative strategy to regulate the DDR in A. baumannii may contribute to its success as a pathogen. IMPORTANCE Acinetobacter baumannii is an opportunistic pathogen quickly gaining antibiotic resistances. Mutagenesis and antibiotic resistance acquisition are linked to the DNA damage response (DDR). However, how the DDR is regulated in A. baumannii remains unknown, since unlike most bacteria, A. baumannii does not follow the regulation of the Escherichia coli paradigm. In this study, we have started to uncover the mechanisms regulating the novel A. baumannii DDR. We have found that a cis-acting 5′ UTR regulates recA transcript stability, RecA protein levels, and DNA damage-induced phenotypic variation. Though 5′ UTRs are known to provide stability to transcripts in bacteria, this is the first example in which it regulates a bimodal DDR response through recA transcript stabilization, potentially enabling cells to have enough RecA for survival and genetic variability. PMID:28320880
Memon, Sameer; Lynch, A Craig; Akhurst, Timothy; Ngan, Samuel Y; Warrier, Satish K; Michael, Michael; Heriot, Alexander G
2014-10-01
Advances in the management of rectal cancer have resulted in an increased application of multimodal therapy with the aim of tailoring therapy to individual patients. Complete pathological response (pCR) is associated with improved survival and may be potentially managed without radical surgical resection. Over the last decade, there has been increasing interest in the ability of functional imaging to predict complete response to treatment. The aim of this review was to assess the role of (18)F-flurordeoxyglucose positron emission tomography (FDG-PET) in prediction of pCR and prognosis in resectable locally advanced rectal cancer. A search of the MEDLINE and Embase databases was conducted, and a systematic review of the literature investigating positron emission tomography (PET) in the prediction of pCR and survival in rectal cancer was performed. Seventeen series assessing PET prediction of pCR were included in the review. Seven series assessed postchemoradiation SUVmax, which was significantly different between response groups in all six studies that assessed this. Nine series assessed the response index (RI) for SUVmax, which was significantly different between response groups in seven series. Thirteen studies investigated PET response for prediction of survival. Metabolic complete response assessed by SUV2max or visual response and RISUVmax showed strong associations with disease-free survival (DFS) and overall survival (OS). SUV2max and RISUVmax appear to be useful FDG-PET markers for prediction of pCR and these parameters also show strong associations with DFS and OS. FDG-PET may have a role in outcome prediction in patients with advanced rectal cancer.
Tumor Response and Survival Predicted by Post-Therapy FDG-PET/CT in Anal Cancer
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schwarz, Julie K.; Siegel, Barry A.; Dehdashti, Farrokh
2008-05-01
Purpose: To evaluate the response to therapy for anal carcinoma using post-therapy imaging with positron emission tomography (PET)/computed tomography and F-18 fluorodeoxyglucose (FDG) and to compare the metabolic response with patient outcome. Patients and Methods: This was a prospective cohort study of 53 consecutive patients with anal cancer. All patients underwent pre- and post-treatment whole-body FDG-PET/computed tomography. Patients had been treated with external beam radiotherapy and concurrent chemotherapy. Whole-body FDG-PET was performed 0.9-5.4 months (mean, 2.1) after therapy completion. Results: The post-therapy PET scan did not show any abnormal FDG uptake (complete metabolic response) in 44 patients. Persistent abnormal FDGmore » uptake (partial metabolic response) was found in the anal tumor in 9 patients. The 2-year cause-specific survival rate was 94% for patients with a complete vs. 39% for patients with a partial metabolic response in the anal tumor (p = 0.0008). The 2-year progression-free survival rate was 95% for patients with a complete vs. 22% for patients with a partial metabolic response in the anal tumor (p < 0.0001). A Cox proportional hazards model of survival outcome indicated that a complete metabolic response was the most significant predictor of progression-free survival in our patient population (p = 0.0003). Conclusions: A partial metabolic response in the anal tumor as determined by post-therapy FDG-PET is predictive of significantly decreased progression-free and cause-specific survival after chemoradiotherapy for anal cancer.« less
ERIC Educational Resources Information Center
Birkeland, Karl W.; Halfpenny, James C.
1987-01-01
Discusses some of the ecological variables involved with plant and animal survival during the winter months. Addresses the effects of changing climatic conditions on habitats, foot-loading indexes, and the overall concept of adaptation. Provides some simple teaching activities dealing with winter survival. (TW)
Goeppert, Benjamin; Frauenschuh, Lena; Zucknick, Manuela; Roessler, Stephanie; Mehrabi, Arianeb; Hafezi, Mohammadreza; Stenzinger, Albrecht; Warth, Arne; Pathil, Anita; Renner, Marcus; Schirmacher, Peter; Weichert, Wilko
2015-01-01
Background: Biliary tract cancers (BTC) are rare malignant tumours with a poor prognosis. Previously, we have presented a detailed characterisation of the inflammatory infiltrate in BTC. Here, we analysed the impact of the expression of major histocompatibility complex class I (MHC I) on patient survival and the quantity, as well as the quality of tumour-infiltrating immune cell types in BTC. Methods: MHC I expression was assessed semi-quantitatively in 334 BTC, including extrahepatic (n=129) and intrahepatic cholangiocarcinomas (n=146), as well as adenocarcinomas of the gallbladder (n=59). In addition, 71 high-grade biliary intraepithelial lesions (BilIN 3) were included. Results were correlated with data on antitumour inflammation and investigated with respect to their association with clinicopathological variables and patient survival. Results: BTC showed a wide spectrum of different MHC I expression patterns ranging from complete negativity in some tumours to strong homogenous expression in others. In BilIN 3, significantly higher MHC I expression levels were seen compared to invasive tumours (P=0.004). Patients with strong tumoural MHC I expression had a significantly higher overall survival probability (median survival benefit: 8 months; P=0.006). MHC I expression strongly correlated with the number of tumour-infiltrating T-lymphocytes (CD4+ and CD8+) and macrophages. Conclusions: Differences of MHC I expression predict patient outcome and show correlations with specific components of the inflammatory infiltrate in BTC. These findings contribute to a better understanding of immune response and immune escape phenomena in cholangiocarcinogenesis. PMID:26461054
Equilino, Mirjam; Théodoloz, Vincent; Gorgas, Daniela; Doherr, Marcus G; Heilmann, Romy M; Suchodolski, Jan S; Steiner, Jörg M; Burgener Dvm, Iwan A
2015-01-01
To evaluate serum concentrations of biochemical markers and survival time in dogs with protein-losing enteropathy (PLE). Prospective study. 29 dogs with PLE and 18 dogs with food-responsive diarrhea (FRD). Data regarding serum concentrations of various biochemical markers at the initial evaluation were available for 18 of the 29 dogs with PLE and compared with findings for dogs with FRD. Correlations between biochemical marker concentrations and survival time (interval between time of initial evaluation and death or euthanasia) for dogs with PLE were evaluated. Serum C-reactive protein concentration was high in 13 of 18 dogs with PLE and in 2 of 18 dogs with FRD. Serum concentration of canine pancreatic lipase immunoreactivity was high in 3 dogs with PLE but within the reference interval in all dogs with FRD. Serum α1-proteinase inhibitor concentration was less than the lower reference limit in 9 dogs with PLE and 1 dog with FRD. Compared with findings in dogs with FRD, values of those 3 variables in dogs with PLE were significantly different. Serum calprotectin (measured by radioimmunoassay and ELISA) and S100A12 concentrations were high but did not differ significantly between groups. Seventeen of the 29 dogs with PLE were euthanized owing to this disease; median survival time was 67 days (range, 2 to 2,551 days). Serum C-reactive protein, canine pancreatic lipase immunoreactivity, and α1-proteinase inhibitor concentrations differed significantly between dogs with PLE and FRD. Most initial biomarker concentrations were not predictive of survival time in dogs with PLE.
Alarcón, Graciela S; McGwin, Gerald; Bertoli, Ana M; Fessler, Barri J; Calvo-Alén, Jaime; Bastian, Holly M; Vilá, Luis M; Reveille, John D
2007-09-01
In patients with systemic lupus erythematosus (SLE), hydroxychloroquine prevents disease flares and damage accrual and facilitates the response to mycophenolate mofetil in those with renal involvement. A study was undertaken to determine whether hydroxychloroquine also exerts a protective effect on survival. Patients with SLE from the multiethnic LUMINA (LUpus in MInorities: NAture vs nurture) cohort were studied. A case-control study was performed within the context of this cohort in which deceased patients (cases) were matched for disease duration (within 6 months) with alive patients (controls) in a proportion of 3:1. Survival was the outcome of interest. Propensity scores were derived by logistic regression to adjust for confounding by indication as patients with SLE with milder disease manifestations are more likely to be prescribed hydroxychloroquine. A conditional logistic regression model was used to estimate the risk of death and hydroxychloroquine use with and without the propensity score as the adjustment variable. There were 608 patients, of whom 61 had died (cases). Hydroxychloroquine had a protective effect on survival (OR 0.128 (95% CI 0.054 to 0.301 for hydroxychloroquine alone and OR 0.319 (95% CI 0.118 to 0.864) after adding the propensity score). As expected, the propensity score itself was also protective. Hydroxychloroquine, which overall is well tolerated by patients with SLE, has a protective effect on survival which is evident even after taking into consideration the factors associated with treatment decisions. This information is of importance to all clinicians involved in the care of patients with SLE.
Motlló, Cristina; Ribera, Josep-Maria; Morgades, Mireia; Granada, Isabel; Montesinos, Pau; Mercadal, Santiago; González-Campos, José; Moreno, María-José; Barba, Pere; Cervera, Marta; Barrios, Manuel; Novo, Andrés; Bernal, Teresa; Hernández-Rivas, Jesús-María; Abella, Eugenia; Amigo, María-Luz; Tormo, Mar; Martino, Rodrigo; Lavilla, Esperanza; Bergua, Juan; Serrano, Alfons; García-Belmonte, Daniel; Guàrdia, Ramon; Grau, Javier; Feliu, Evarist
2018-01-01
About 25-35% of adult patients with acute lymphoblastic leukemia show the Philadelphia (Ph) chromosome. Few series have evaluated the prognosis of additional cytogenetic alterations (ACA) to the Ph chromosome. We analyzed the frequency, type and prognostic significance ofACA in adults (18-60 years) treated in the ALL-Ph-08 trial. Fifty-two out of 74 patients (70%) showed ACA and 19 (26%) presented monosomies associated with t(9;22) (monosomal karyotype, MK). Similar complete response (CR) rate, CR duration, overall survival and event-free survival (EFS) were observed in patients with or without ACA, but patients with MK showed shorter CR duration and EFS than the remaining. On multivariate analysis, the only variable with prognostic impact for CR duration and EFS was the presence of MK (p = .003 and p = .036, respectively). Although ACA associated with the Ph chromosome are frequent, only monosomies were associated with poor prognosis in this group of patients.
Kanakasetty, Govind Babu; Kuntejowdahalli, Lakshmaiah; Thanky, Aditi Harsh; Dasappa, Lokanatha; Jacob, Linu Abraham; Mallekavu, Suresh Babu; Kumari, Prasanna
2017-01-01
Chronic myeloid leukemia (CML) is a myeloproliferative disorder characterized by Philadelphia (Ph) chromosome with classical t(9;22)(q34;q11) seen in up to 90% of cases. However 5% to 10% of patients who present with variant Ph translocations (vPh) have been an area of research for their significance in predicting response to various therapies including tyrosine kinase inhibitors as well as prognosticating survival outcomes for many years involving varied patient populations, with conflicting results. We retrospectively analyzed our data from January 2002 to December 2014. Patients with vPh in chronic phase of CML (CML-CP) were analyzed with respect to their demographic parameters, response to imatinib therapy, and survival and their data were compared with data of patients with classical Ph translocation (cPh). Of 615 patients diagnosed with CML-CP, 72 patients (11.7%) showed vPh. Most common chromosomes involved in these translocations were 14 (13.9%), 11 (12.5%), 19 (9.7%), and 7 (8.3%). Rates of complete hematological response, complete cytogenetic response, and major molecular response were not statistically different between the groups. At 5 years, event-free survival, failure-free survival, progression-free survival, and overall survival were 60% versus 67.9%, 62.7% versus 69.7%, 84.7% versus 92.1%, and 87.5% versus 92.4%, respectively, in vPh and cPh. The differences in survival were statistically not significant. To our knowledge, this is the largest series of variant translocations in CML-CP, pertaining to the Indian population. Our data suggest that the presence of vPh in CML has no significant effect in predicting response to imatinib as well as in prognosticating survival. Copyright © 2016 Elsevier Inc. All rights reserved.
Ji, Yan; Vogel, Rachel Isaksson; Lou, Emil
2016-01-01
Background Pituitary carcinomas (PC) and atypical pituitary adenomas (APA) are rare variants of pituitary tumors for which no evidence-based treatment currently exists. We sought to determine whether temozolomide represents an effective chemotherapeutic option for patients with PC and APA. Methods A systematic review was performed using all published cases of PC and APA treated with temozolomide, and for which information on treatment regimen, clinical response, and survival could be identified. The primary goal of this analysis was to describe overall survival and progression-free survival among PC and APA patients after temozolomide treatment. Secondary goals included assessment of response rate and biomarkers of response. Results We identified 57 cases and obtained follow-up data on 54 patients (31 APA and 23 PC) for analysis. Estimates of 5-year progression-free survival and overall survival were 21.9% and 57.4% for patients with APA and 36.1% and 56.2% for patients with PC. Among those who responded to temozolomide, overall survival was marginally statistically significantly greater for patients on long-term temozolomide therapy compared with those who were not (5-year overall survival 91.7% vs 54.1%, P = .08); Progression-free survival results were similar but not statistically significant. The objective response rate was 48.4% for patients with APA and 65.2% for patients with PC. Stable disease occurred in 29% of APA and 17.4% of PC patients. Neither histology nor expression of Ki-67 correlated with response; however, negative O6-methylguanine-DNA methyltransferase staining was strongly related to response to temozolomide in patients with APA (P < .001). Conclusions Temozolomide is an effective treatment of both PC and APA, and long-term treatment can be considered for particularly aggressive cases. PMID:27551432
Kaseb, Ahmed O; Shindoh, Junichi; Patt, Yehuda Z; Roses, Robert E; Zimmitti, Giuseppe; Lozano, Richard D; Hassan, Manal M; Hassabo, Hesham M; Curley, Steven A; Aloia, Thomas A; Abbruzzese, James L; Vauthey, Jean-Nicolas
2013-09-15
The purpose of this study was to evaluate the factors associated with response rate, resectability, and survival after cisplatin/interferon α-2b/doxorubicin/5-fluorouracil (PIAF) combination therapy in patients with initially unresectable hepatocellular carcinoma. The study included 2 groups of patients treated with conventional high-dose PIAF (n = 84) between 1994 and 2003 and those without hepatitis or cirrhosis treated with modified PIAF (n = 33) between 2003 and 2012. Tolerance of chemotherapy, best radiographic response, rate of conversion to curative surgery, and overall survival were analyzed and compared between the 2 groups, and multivariate and logistic regression analyses were applied to identify predictors of response and survival. The modified PIAF group had a higher median number of PIAF cycles (4 versus 2, P = .049), higher objective response rate (36% versus 15%, P = .013), higher rate of conversion to curative surgery (33% versus 10%, P = .004), and longer median overall survival (21.3 versus 10.6 months, P = .002). Multivariate analyses confirmed that positive hepatitis B serology (hazard ratio [HR] = 1.68; 95% confidence interval [CI] = 1.08-2.59) and Eastern Cooperative Oncology Group performance status ≥ 2 (HR = 1.75; 95% CI = 1.04-2.93) were associated with worse survival whereas curative surgical resection after PIAF treatment (HR = 0.15; 95% CI = 0.07-0.35) was associated with improved survival. In patients with initially unresectable hepatocellular carcinoma, the modified PIAF regimen in patients with no hepatitis or cirrhosis is associated with improved response, resectability, and survival. © 2013 American Cancer Society.
Kaseb, Ahmed O.; Shindoh, Junichi; Patt, Yehuda Z.; Roses, Robert E.; Zimmitti, Giuseppe; Lozano, Richard D.; Hassan, Manal M.; Hassabo, Hesham M.; Curley, Steven A.; Aloia, Thomas A.; Abbruzzese, James L.; Vauthey, Jean-Nicolas
2013-01-01
Purpose The purposes of this study was to evaluate the factors associated with response rate, resectability, and survival after cisplatin/interferon α-2b/doxorubicin/5-flurouracil (PIAF) combination therapy in patients with initially unresectable hepatocellular carcinoma (HCC). Patients and Methods The study included two groups of patients treated with conventional high-dose PIAF (n=84) between 1994 and 2003 and those without hepatitis or cirrhosis treated with modified PIAF (n=33) between 2003 and 2012. Tolerance of chemotherapy, best radiographic response, rate of conversion to curative surgery, and overall survival were analyzed and compared between the two groups, and multivariate and logistic regression analyses were applied to identify predictors of response and survival. Results The modified PIAF group had a higher median number of PIAF cycles (4 vs. 2, P = .049), higher objective response rate (36% vs. 15%, P = .013), higher rate of conversion to curative surgery (33% vs. 10%, P = .004), and longer median overall survival (21.3 vs. 10.6 months, P = .002). Multivariate analyses confirmed that positive hepatitis B serology (hazard ratio [HR], 1.68; 95% CI, 1.08 to 2.59) and Eastern Cooperative Oncology Group performance status ≥2 (HR, 1.75; 95% CI 1.04 to 2.93) were associated with worse survival while curative surgical resection after PIAF treatment (HR, 0.15; 95% CI, 0.07 to 0.35) was associated with improved survival. Conclusions In patients with initially unresectable HCC, the modified PIAF regimen in patients with no hepatitis or cirrhosis is associated with improved response, resectability, and survival. PMID:23821538
Modeling demographic performance of northern spotted owls relative to forest habitat in Oregon
Olson, Gail S.; Glenn, Elizabeth M.; Anthony, Robert G.; Forsman, Eric D.; Reid, Janice A.; Loschl, Peter J.; Ripple, William J.
2004-01-01
Northern spotted owls (Strix occidentalis caurina) are known to be associated with late-successional forests in the Pacific Northwest of the United States, but the effects of habitat on their demographic performance are relatively unknown. We developed statistical models relating owl survival and productivity to forest cover types within the Roseburg Study Area in the Oregon Coast Range of Oregon, USA. We further combined these demographic parameters using a Leslie-type matrix to obtain an estimate of habitat fitness potential for each owl territory (n = 94). We used mark–recapture methods to develop models for survival and linear mixed models for productivity. We measured forest composition and landscape patterns at 3 landscape scales centered on nest and activity sites within owl territories using an aerial photo-based map and a Geographic Information System (GIS). We also considered additional covariates such as age, sex, and presence of barred owls (Strix varia), and seasonal climate variables (temperature and precipitation) in our models. We used Akaike's Information Criterion (AIC) to rank and compare models. Survival had a quadratic relationship with the amount of late- and mid-seral forests within 1,500 m of nesting centers. Survival also was influenced by the amount of precipitation during the nesting season. Only 16% of the variability in survival was accounted for by our best model, but 85% of this was due to the habitat variable. Reproductive rates fluctuated biennially and were positively related to the amount of edge between late- and mid-seral forests and other habitat classes. Reproductive rates also were influenced by parent age, amount of precipitation during nesting season, and presence of barred owls. Our best model accounted for 84% of the variability in productivity, but only 3% of that was due to the habitat variable. Estimates of habitat fitness potential (which may range from 0 to infinity) for the 94 territories ranged from 0.74 to 1.15 (x̄ = 1.05, SE = 0.07). All but 1 territory had 95% confidence intervals overlapping 1.0, indicating a potentially stable population based on habitat pattern. Our results seem to indicate that while mid- and late-seral forests are important to owls, a mixture of these forest types with younger forest and nonforest may be best for owl survival and reproduction. Our results are consistent with those of researchers in northern California, USA, who used similar methods in their analyses. However, we believe that given the low variability in survival and productivity attributed to habitat, further study is needed to confirm our conclusions before they can be used to guide forest management actions for spotted owls.
Correlates of engaging in survival sex among homeless youth and young adults.
Walls, N Eugene; Bell, Stephanie
2011-09-01
Using a sample of 1,625 homeless youth and young adults aged 10 to 25 from 28 different states in the United States, this study examines the correlates of having engaged in survival sex. Findings suggest that differences exist based on demographic variables (gender, age, race, and sexual orientation), lifetime drug use (inhalants, Valium™, crack cocaine, alcohol, Coricidin™, and morphine), recent drug use (alcohol, ecstasy, heroin, and methamphetamine), mental health variables (suicide attempts, familial history of substance use, and having been in substance abuse treatment), and health variables (sharing needles and having been tested for HIV). In addition to replicating previous findings, this study's findings suggest that African American youth; gay, lesbian, or bisexual youth; and youth who had been tested for HIV were significantly more likely to have engaged in survival sex than White, heterosexual youth, and youth who had not been tested for HIV, respectively. Implications for interventions with youth and suggestions for future research are discussed.
Yang, Guo-Jing; Tanner, Marcel; Utzinger, Jürg; Malone, John B; Bergquist, Robert; Chan, Emily Y Y; Gao, Qi; Zhou, Xiao-Nong
2012-12-21
A sound understanding of malaria transmission patterns in the People's Republic of China (P.R. China) is crucial for designing effective surveillance-response strategies that can guide the national malaria elimination programme (NMEP). Using an established biology-driven model, it is expected that one may design and refine appropriate surveillance-response strategies for different transmission zones, which, in turn, assist the NMEP in the ongoing implementation period (2010-2020) and, potentially, in the post-elimination stage (2020-2050). Environmental data obtained from 676 locations across P.R. China, such as monthly temperature and yearly relative humidity (YRH), for the period 1961-2000 were prepared. Smoothed surface maps of the number of months suitable for parasite survival derived from monthly mean temperature and YRH were generated. For each decade, the final malaria prediction map was overlaid by two masked maps, one showing the number of months suitable for parasite survival and the other the length of YRH map in excess of 60%. Considering multiple environmental factors simultaneously, the environmental variables suitable for malaria transmission were found to have shifted northwards, which was especially pronounced in northern P.R. China. The unstable suitable regions (transmission periods between five and six months) showed increased transmission intensity due to prolonged suitable periods, especially in the central part of the country. Adequate and effective surveillance-response strategies for NMEP should be designed to achieve the goal of malaria elimination in P.R. China by 2020, especially in the zones predicted to be the most vulnerable for climate change.
Suryan, Robert M.; Saba, Vincent S.; Wallace, Bryan P.; Hatch, Scott A.; Frederiksen, Morten; Wanless, Sarah
2009-01-01
Variation in life history traits of organisms is thought to reflect adaptations to environmental forcing occurring from bottom-up and top-down processes. Such variation occurs not only among, but also within species, indicating demographic plasticity in response to environmental conditions. From a broad literature review, we present evidence for ocean basin- and large marine ecosystem-scale variation in intra-specific life history traits, with similar responses occurring among trophic levels from relatively short-lived secondary producers to very long-lived apex predators. Between North Atlantic and North Pacific Ocean basins, for example, species in the Eastern Pacific exhibited either later maturation, lower fecundity, and/or greater annual survival than conspecifics in the Western Atlantic. Parallel variations in life histories among trophic levels also occur in adjacent seas and between eastern vs. western ocean boundaries. For example, zooplankton and seabird species in cooler Barents Sea waters exhibit lower fecundity or greater annual survival than conspecifics in the Northeast Atlantic. Sea turtles exhibit a larger size and a greater reproductive output in the Western Pacific vs. Eastern Pacific. These examples provide evidence for food-web-wide modifications in life history strategies in response to environmental forcing. We hypothesize that such dichotomies result from frequency and amplitude shifts in resource availability over varying temporal and spatial scales. We review data that supports three primary mechanisms by which environmental forcing affects life history strategies: (1) food-web structure; (2) climate variability affecting the quantity and seasonality of primary productivity; (3) bottom-up vs. top-down forcing. These proposed mechanisms provide a framework for comparisons of ecosystem function among oceanic regions (or regimes) and are essential in modeling ecosystem response to climate change, as well as for creating dynamic ecosystem-based marine conservation strategies.
The deprivation syndrome is the driving force of phylogeny, ontogeny and oncogeny.
Heininger, K
2001-01-01
Energy is the motor of life. Energy ensures the organism's survival and competitive advantage for reproductive success. For almost 3 billion years, unicellular organisms were the only life form on earth. Competition for limited energy resources and raw materials exerted an incessant selective pressure on organisms. In the adverse environment and due to their 'feast and famine' life style, hardiness to a variety of stressors, particularly to nutrient deprivation, was the selection principle. Both resistance and mutagenic adaptation to stressors were established as survival strategies by means of context-specific processes creating stability or variability of DNA sequence. The conservation of transduction pathways and functional homology of effector molecules clearly bear witness that the principles of life established during prokaryotic and eukaryotic unicellular evolution, although later diversified, have been unshakably cast to persist during metazoan phylogenesis. A wealth of evidence suggests that unicellular organisms evolved the phenomena of differentiation and apoptosis, sexual reproduction, and even aging, as responses to environmental challenges. These evolutionary accomplishments were elaborated from the dichotomous resistance/mutagenesis response and sophisticated the capacity of cells to tune their genetic information to changing environmental conditions. Notably, the social deprivation responses, differentiation and apoptosis, evolved as intercellularly coordinated events: a multitude of differentiation processes were elaborated from sporulation, the prototypic stress resistance response, while apoptosis, contrary to current concepts, is no altruistic cell suicide but was programmed as a mutagenic survival response; this response, however, is socially thwarted leading into mutagenic error catastrophe. In the hybrid differentiation-apoptosis process, cytocide and cannibalism of apoptotic cells thus serve the purpose of fueling the survival of the selfish genes in the differentiating cells. However, successful mutagenesis, although repressed, persisted in the asocial stress response of carcinogenesis as a regression to primitive unicellular behavior following failure of intercellular communication. While somatic mutagenesis was largely prevented, Metazoa elaborated germ cell mutagenesis as an evolutionary vehicle. Genetic competence, a primitive, stress-induced mating behavior, evolved into sexual reproduction which harnessed mutagenesis by subjecting highly mutable germ cells to a rigid viability selection. These processes were programmatically fixed as life- and cell-cycle events but retained their deprivation response phenotypes. Thus, the differentiation-apoptosis tandem evolved as the 'clay' to mold the specialized structures and functions of a multicellular organism while sexual reproduction elaborated the principle of quality-checked mutagenesis to create the immense diversity of Metazoa following the Cambrian explosion. Throughout these events, reactive oxygen and nitrogen species, which are regulated by energy homeostasis, shape the genetic information in a regulated but random, uncoded process providing the fitness-related feedback of phenotype to genotype. The interplay of genes and environment establishes a dynamic stimulus-response feedback cycle which, in animate nature, may be the organizing principle to contrive the reciprocal duality of energy and matter.
Balar, Arjun V; Galsky, Matthew D; Rosenberg, Jonathan E; Powles, Thomas; Petrylak, Daniel P; Bellmunt, Joaquim; Loriot, Yohann; Necchi, Andrea; Hoffman-Censits, Jean; Perez-Gracia, Jose Luis; Dawson, Nancy A; van der Heijden, Michiel S; Dreicer, Robert; Srinivas, Sandy; Retz, Margitta M; Joseph, Richard W; Drakaki, Alexandra; Vaishampayan, Ulka N; Sridhar, Srikala S; Quinn, David I; Durán, Ignacio; Shaffer, David R; Eigl, Bernhard J; Grivas, Petros D; Yu, Evan Y; Li, Shi; Kadel, Edward E; Boyd, Zachary; Bourgon, Richard; Hegde, Priti S; Mariathasan, Sanjeev; Thåström, AnnChristine; Abidoye, Oyewale O; Fine, Gregg D; Bajorin, Dean F
2017-01-01
Summary Background First-line chemotherapy for patients with cisplatin-ineligible locally-advanced or metastatic urothelial carcinoma (mUC) is associated with short response duration, poor survival, and high toxicity. This multicenter, 2-cohort phase 2 study evaluated atezolizumab (anti–programmed death-ligand 1 [PD-L1]) as treatment for mUC in this setting, as well as in later lines. Methods In a cohort of previously untreated patients who were cisplatin ineligible, atezolizumab was given 1200 mg every 3 weeks until progression. The primary endpoint was independently confirmed objective response rate per Response Evaluation Criteria In Solid Tumors v1.1 (central review), evaluated in pre-specified subgroups based on PD-L1 expression and in all patients. Secondary endpoints included response duration, progression-free survival, overall survival, and safety. Exploratory analyses included biomarker correlates of response and survival. This study is registered with ClinicalTrials.gov, number NCT02108652. Findings Of 119 patients who received atezolizumab in the first-line setting, 83 (70%) had baseline renal impairment, and 24 (20%) had Eastern Cooperative Oncology Group performance status 2. At 17·2 months’ median follow-up, the objective response rate was 23% (95% CI 16–31), the complete response rate was 9%, and 19 of 27 responses were ongoing. Median response duration was not reached. Responses occurred across all PD-L1 and poor prognostic factor subgroups. Median progression-free survival was 2·7 months. Median overall survival was 15·9 months. Tumour mutation load was associated with response. Treatment-related adverse events ≥10% were fatigue, diarrhoea, and pruritus. One treatment-related death (sepsis) occurred. Nine patients (8%) had an adverse event leading to treatment discontinuation. Immune-mediated events occurred in 14 (12%) patients. Interpretation Atezolizumab demonstrated encouraging durable response rates, survival, and tolerability, supporting its therapeutic use in untreated mUC. Funding F. Hoffmann-La Roche Ltd./Genentech, Inc., a member of the Roche Group. PMID:27939400
Stanley, Thomas R.; Aldridge, Cameron L.; Joanne Saher,; Theresa Childers,
2015-01-01
The Gunnison Sage-Grouse (Centrocercus minimus) is a species of conservation concern and is a candidate for listing under the U.S. Endangered Species Act because of substantial declines in populations from historic levels. It is thought that loss, fragmentation, and deterioration of sagebrush (Artemisia spp.) habitat have contributed to the decline and isolation of this species into seven geographically distinct subpopulations. Nest survival is known to be a primary driver of demography of Greater Sage-Grouse (C. urophasianus), but no unbiased estimates of daily nest survival rates (hereafter nest survival) exist for Gunnison Sage-Grouse or published studies identifying factors that influence nest survival. We estimated nest survival of Gunnison Sage-Grouse for the western portion of Colorado's Gunnison Basin subpopulation, and assessed the effects and relative importance of local- and landscape-scale habitat characteristics on nest survival. Our top performing model was one that allowed variation in nest survival among areas, suggesting a larger landscape-area effect. Overall nest success during a 38-day nesting period (egg-laying plus incubation) was 50% (daily survival rate; SE = 0.982 [0.003]), which is higher than previous estimates for Gunnison Sage-Grouse and generally higher than published for the closely related Greater Sage-Grouse. We did not find strong evidence that local-scale habitat variables were better predictors of nest survival than landscape-scale predictors, nor did we find strong evidence that any of the habitat variables we measured were good predictors of nest survival. Nest success of Gunnison Sage-Grouse in the western portion of the Gunnison Basin was higher than previously believed.
Prognostic discrimination in "good-risk" chronic granulocytic leukemia.
Sokal, J E; Cox, E B; Baccarani, M; Tura, S; Gomez, G A; Robertson, J E; Tso, C Y; Braun, T J; Clarkson, B D; Cervantes, F
1984-04-01
The prognostic significance of disease features recorded at the time of diagnosis was examined among 813 patients with Philadelphia chromosome-positive, nonblastic chronic granulocytic leukemia (CGL) collected from six European and American series. The survival pattern for this population was typical of "good-risk" patients, and median survival was 47 mo. There were multiple interrelationships among different disease features, which led to highly significant correlations with survival for some that had no primary prognostic significance, such as hematocrit. Multivariable regression analysis indicated that spleen size and the percentage of circulating blasts were the most important prognostic indicators. These features, and age, behaved as continuous variables with progressively unfavorable import at higher values. The platelet count did not influence survival significantly at values below 700 X 10(9)/liter but was increasingly unfavorable above this level. Basophils plus eosinophils over 15%, more than 5% marrow blasts, and karyotypic abnormalities in addition to the Ph1 were also significant unfavorable signs. The Cox model, generated with four variables representing percent blasts, spleen size, platelet count, and age, provided a useful representation of risk status in this population, with good fit between predicted and observed survival over more than a twofold survival range. A hazard function derived from half of the patient population successfully segregated the remainder into three groups with significantly different survival patterns. We conclude that it should be possible to identify a lower risk group of patients with a 2-yr survival of 90%, subsequent risk averaging somewhat less than 20%/yr and median survival of 5 yr, an intermediate group, and a high-risk group with a 2-yr survival of 65%, followed by a death rate of about 35%/yr and median survival of 2.5 yr.
NASA Astrophysics Data System (ADS)
El Naqa, I.; Suneja, G.; Lindsay, P. E.; Hope, A. J.; Alaly, J. R.; Vicic, M.; Bradley, J. D.; Apte, A.; Deasy, J. O.
2006-11-01
Radiotherapy treatment outcome models are a complicated function of treatment, clinical and biological factors. Our objective is to provide clinicians and scientists with an accurate, flexible and user-friendly software tool to explore radiotherapy outcomes data and build statistical tumour control or normal tissue complications models. The software tool, called the dose response explorer system (DREES), is based on Matlab, and uses a named-field structure array data type. DREES/Matlab in combination with another open-source tool (CERR) provides an environment for analysing treatment outcomes. DREES provides many radiotherapy outcome modelling features, including (1) fitting of analytical normal tissue complication probability (NTCP) and tumour control probability (TCP) models, (2) combined modelling of multiple dose-volume variables (e.g., mean dose, max dose, etc) and clinical factors (age, gender, stage, etc) using multi-term regression modelling, (3) manual or automated selection of logistic or actuarial model variables using bootstrap statistical resampling, (4) estimation of uncertainty in model parameters, (5) performance assessment of univariate and multivariate analyses using Spearman's rank correlation and chi-square statistics, boxplots, nomograms, Kaplan-Meier survival plots, and receiver operating characteristics curves, and (6) graphical capabilities to visualize NTCP or TCP prediction versus selected variable models using various plots. DREES provides clinical researchers with a tool customized for radiotherapy outcome modelling. DREES is freely distributed. We expect to continue developing DREES based on user feedback.
The Effect of Ballistic Impacts on the High Cycle Fatigue Properties of Ti-48Al-2Nb-2Cr (at.%)
NASA Technical Reports Server (NTRS)
Draper, S. L.; Lerch, B. A.; Pereira, J. M.; Nathal, M. V.; Austin, C. M.; Erdman, O.
2000-01-01
The ability of gamma - TiAl to withstand potential foreign and/or domestic object damage is a technical risk to the implementation of gamma - TiAl in low pressure turbine (LPT) blade applications. The overall purpose of the present study was to determine the influence of ballistic impact damage on the high cycle fatigue strength of gamma - TiAl simulated LPT blades. Impact and specimen variables included ballistic impact energy, projectile hardness, impact temperature, impact location, and leading edge thickness. The level of damage induced by the ballistic impacting was studied and quantified on both the impact (front) and backside of the specimens. Multiple linear regression was used to model the cracking and fatigue response as a function of the impact variables. Of the impact variables studied, impact energy had the largest influence on the response of gamma - TiAl to ballistic impacting. Backside crack length was the best predictor of remnant fatigue strength for low energy impacts (<0.74J) whereas Hertzian crack length (impact side damage) was the best predictor for higher energy impacts. The impacted gamma - TiAl samples displayed a classical mean stress dependence on the fatigue strength. For the fatigue design stresses of a 6th stage LPT blade in a GE90 engine, a Ti-48Al-2Nb-2Cr LPT blade would survive an impact of normal service conditions.
Gouvêa, Devin Y.; Aprison, Erin Z.; Ruvinsky, Ilya
2015-01-01
Natural environments are considerably more variable than laboratory settings and often involve transient exposure to stressful conditions. To fully understand how organisms have evolved to respond to any given stress, prior experience must therefore be considered. We investigated the effects of individual and ancestral experience on C. elegans reproduction. We documented ways in which cultivation at 15°C or 25°C affects developmental time, lifetime fecundity, and reproductive performance after severe heat stress that exceeds the fertile range of the organism but is compatible with survival and future fecundity. We found that experience modulates multiple aspects of reproductive physiology, including the male and female germ lines and the interaction between them. These responses vary in their environmental sensitivity, suggesting the existence of complex mechanisms for coping with unpredictable and stressful environments. PMID:26713620
Far-field mission planning for nap-of-the-earth flight
NASA Technical Reports Server (NTRS)
Deutsch, Owen L.; Desai, Mukund; Mcgee, Leonard A.
1987-01-01
In the face of numerically superior hostile forces, deployment of individual vehicles to the right place, at the right time, and the ability to plan missions with less conservatism, will become significant force multipliers. Far-field mission planning is one of the enabling technologies that will facilitate force coordination through management of mission timeline, vehicle survivability and fuel constraints. On-board replanning is required to deal responsively with departures from nominal plan execution that result from imperfect knowledge of and temporal variability in the mission environment. The far-field planning problem is posed as a constrained optimization problem and algorithms and structural organization are proposed for the solution.
Outcomes in patients with mucosal melanomas.
Keller, Deborah S; Thomay, Alan A; Gaughan, John; Olszanski, Anthony; Wu, Hong; Berger, Adam C; Farma, Jeffrey M
2013-12-01
Our goal was to evaluate the different subtypes of mucosal melanoma and describe specific variables that predict outcomes. Prospective review of two tertiary care center databases identified 76 mucosal melanoma patients; 73 with complete records were included. Demographic and clinical data were analyzed. Cox regression determined variables impacting recurrence and survival. In the 73 patients, the mean age was 64 years, and 74% were female. Sixty-seven percent presented with lymph node involvement, and 73% had ulcerated tumors. Major sites affected were nasal/palate/oral (36%), vulvar/vaginal/cervical (48%), and anorectal (15%). Mean overall and disease-free survival were 56.9 and 27.2 months. Variables associated with decreased survival included: lymphovascular invasion (HR17.70, P = 0.0093), Caucasian race (HR3.02, P = 0.0362), nasal/palate/oral sub-group (HR1.85, P = 0.026), Breslow thickness (HR1.23, P = 0.00004), T stage (HR1.34, P = 0.0075), M stage (HR3.03, P = 0.0039), and chemotherapy (HR3.13, P = 0.0002). The worst prognosis was seen in the nasal/palate/oral sub-group, with a median overall survival of 9.7 months and recurrence-free time of 4.5 months. This subtype also demonstrated high lymph node positivity, ulceration, and larger tumor size. The nasal, palate, oral subtype has the worst prognosis compared to other mucosal melanoma locations. Studies are ongoing to evaluate pathologic and genomic variables that may predict outcomes. © 2013 Wiley Periodicals, Inc.
Interaction between Hydrosphere and Biosphere: Challenges and Opportunities
NASA Astrophysics Data System (ADS)
Kumar, P.; Sivapalan, M.
2007-12-01
Vegetated terrestrial ecosystems and the overlying atmosphere are dynamically linked though the continuous transfer of mass, energy and momentum. The hydrologic variability interacts with the vegetation at time scales ranging from hours to days to inter-annual and decadal. The existing distribution of ecosystems is a result of evolutionary selections in response to environmental constraints which are themselves modified as terrestrial systems evolve until reaching a dynamic equilibrium. However this balance is changing, often rapidly, in response to anthropogenic influences such as climate change, land use/land cover change, and urban and agricultural expansions. Evidence suggests that vegetation response is adaptive in that they alter their survival strategies in response to environmental change, for example, through development of deep rooting and using hydraulic redistribution to better utilize the available moisture in the deeper soil layers. Yet little is known on how this impacts the hydrologic cycle and its variability. Active and adaptive control of vegetation and atmospheric flow moves soil-moisture that is no longer constrained by watershed boundaries. How do the atmospheric and terrestrial moisture, and vegetation interact to produce the observed variability in the water cycle and how does/will this variability change in response to the anthropogenic influences? What are the ecological consequences of this change? These broad questions lie at the heart of understanding the interaction between the hydrosphere and biosphere. Some specific questions to address are: · How does biosphere mediate the interaction between long time scale sub-surface hydrology and short time scale atmospheric hydrologic cycle? · How has this interaction given rise to the observed self-organized patterns of ecosystems and how do these ecosystems sustain the hydrologic regime needed for their own sustenance? · How are the dynamic regimes of ecohydrologic interactions affected by the anthropogenic impacts of land use/land cover change, elevated CO2 and temperature, water use, etc? · How do these linkages and changes there in alter the biogeochemical cycling in a region? Addressing these challenges is a sub-theme of the synthesis project supported by NSF. In this talk we will describe the progress made in regard to these issues.
Graft-versus-Host Disease Treatment: Predictors of Survival
Levine, John E.; Logan, Brent; Wu, Juan; Alousi, Amin M.; Ho, Vincent; Bolaños-Meade, Javier; Weisdorf, Daniel
2010-01-01
Acute graft-versus-host disease (aGVHD) following allogeneic hematopoietic cell transplant (HCT) is the major reason for non-relapse mortality and thus is a major determinant of long term survival. Clinical trials of new aGVHD treatments are needed in order to identify approaches that will ultimately improve upon HCT survival. At present it is not clear how quickly response to GVHD treatment needs to be established in order to reliably categorize patients at high risk for death or to promptly identify those who might benefit from alternate treatment. Therefore, we analyzed time to response from onset of aGVHD treatment in 180 patients who were enrolled on a national, randomized, phase II aGVHD treatment clinical trial whose initial treatment of GVHD consisted of high dose steroids plus a second immunosuppressive agent. The aim of this analysis was to determine whether time to aGVHD treatment response predicts patient outcomes, especially survival. We used response at 14, 28 and 56 days from initiation of aGVHD treatment to categorize patients for non-relapse mortality and survival. Multivariate analyses and specificity/sensitivity analyses identified that day 28 response (complete or partial response) best categorized patients by non-relapse mortality and survival at 9 months from start of aGVHD treatment. If verified as a reliable predictor of late outcomes following other aGVHD treatment approaches, day 28 response should serve as a standard early endpoint for future trials of aGVHD therapy. PMID:20541024
Conde, Sofia; Borrego, Margarida; Teixeira, Tânia; Teixeira, Rubina; Sá, Anabela; Soares, Paula
2012-01-01
To evaluate the prognostic factors and impact on survival of neoadjuvant oral and infusional chemoradiotherapy in patients with locally advanced rectal cancer. There is still no definitive consensus about the prognostic factors and the impact of neoadjuvant chemoradiotherapy on survival. Some studies have pointed to an improvement in overall survival (OS) and progression-free survival (PFS) in patients with tumor downstaging (TD) and nodal downstaging (ND). A set of 159 patients with LARC were treated preoperatively. Group A - 112 patients underwent concomitant oral chemoradiotherapy: capecitabine or UFT + folinic acid. Group B - 47 patients submitted to concomitant chemoradiation with 5-FU in continuous infusion. 63.6% of patients were submitted to adjuvant chemotherapy. pathologic complete response (pCR) - 18.7%; TD - 55.1%; ND - 76%; loco-regional response - 74.8%. Group B: pCR - 11.4%; TD - 50%; ND - 55.8%; LRR - 54.5%. The loco-regional control was 95.6%. There was no difference in survival between both groups. Those with loco-regional response had better PFS. Tumor and nodal downstaging, loco-regional response and a normal CEA level turned out to be important prognostic factors in locally advanced rectal cancer. Nodal downstaging and loco-regional response were higher in Group A. Those with tumor downstaging and loco-regional response from Group A had better OS. Adjuvant chemotherapy had no impact on survival except in those patients with loco-regional response who achieved a higher PFS.
Does private religious activity prolong survival? A six-year follow-up study of 3,851 older adults.
Helm, H M; Hays, J C; Flint, E P; Koenig, H G; Blazer, D G
2000-07-01
Previous studies have linked higher religious attendance and longer survival. In this study, we examine the relationship between survival and private religious activity. A probability sample of elderly community-dwelling adults in North Carolina was assembled in 1986 and followed for 6 years. Level of participation in private religious activities such as prayer, meditation, or Bible study was assessed by self-report at baseline, along with a wide variety of sociodemographic and health variables. The main outcome was time (days) to death or censoring. During a median 6.3-year follow-up period, 1,137 subjects (29.5%) died. Those reporting rarely to never participating in private religious activity had an increased relative hazard of dying over more frequent participants, but this hazard did not remain significant for the sample as a whole after adjustment for demographic and health variables. When the sample was divided into activity of daily living (ADL) impaired and unimpaired, the effect did not remain significant for the ADL impaired group after controlling for demographic variables (hazard ratio [RH] 1.11, 95% confidence interval [CI] 0.91-1.35). However, the increased hazard remained significant for the ADL unimpaired group even after controlling for demographic and health variables (RH 1.63, 95% CI 1.20-2.21), and this effect persisted despite controlling for numerous explanatory variables including health practices, social support, and other religious practices (RH 1.47, 95% CI 1.07-2.03). Older adults who participate in private religious activity before the onset of ADL impairment appear to have a survival advantage over those who do not.
González-Vicent, Marta; Marín, Catalina; Madero, Luis; Sevilla, Julián; Díaz, Miguel Angel
2005-10-01
The authors retrospectively analyzed postransplantation events in 198 children who underwent hematopoietic stem cell transplantation (HSCT) between 1998 and 2002 to obtain a risk score for pediatric intensive care unit (PICU) admission and to ascertain variables predicting a poor outcome. Thirty-six patients (18%) were admitted to the PICU. Median age was 9 years (range 1-18). On univariate analysis, variables significantly associated with PICU admission were male gender (P = 0.01), more than first complete remission (P = 0.003), allogeneic transplantation (P = 0.001), engraftment syndrome (P = 0.03), and acute graft-versus-host disease grade of at least two (P = 0.05). According to this, patients were divided in two levels of risk (low and high), with a respective probability of PICU admission of 8.8 +/- 2.2% and 63.8 +/- 8.8% (P < 0.0001). Seventeen (47%) patients were discharged from the PICU. The probability of event-free survival after PICU admission at 3 years was 24.2 +/- 7%. On univariate analysis, variables with a negative impact on event-free survival were type of transplantation, inotropic support, a C-reactive protein level of at least 10 mg/dL, and a high O-PRISM score. On multivariate analysis, the only variable that influenced event-free survival was the O-PRISM score (< or =10 points, 54.6 +/- 15.3%; >10 points, 8.6 +/- 5.8%; P = 0.007). In conclusion, the risk of PICU admission may be easily estimated using simple variables. A high O-PRISM score at the time of PICU admission predicts a dismal outcome.
NASA Astrophysics Data System (ADS)
Huret, M.; Petitgas, P.; Woillez, M.
2010-10-01
Dispersal of fish early life stages explains part of the recruitment success, through interannual variability in spawning, transport and survival. Dispersal results from a complex interaction between physical and biological processes acting at different temporal and spatial scales, and at the individual or population level. In this paper we quantify the response of anchovy egg and larval dispersal in the Bay of Biscay to the following sources of variability: vertical larval behaviour, drift duration, adult spawning location and timing, and spatio-temporal variability in the hydrodynamics. We use simulations of Lagrangian trajectories in a 3-dimensional hydrodynamic model, as well as spatial indices describing different properties of the dispersal kernel: the mean transport (distance, direction), its variance, occupation of space by particles and their aggregation. We show that larval drift duration has a major impact on the dispersion at scales of ˜100 km, but that vertical behaviour becomes dominant reducing dispersion at scales of ˜1-10 km. Spawning location plays a major role in explaining connectivity patterns, in conjunction with spawning temporal variability. Interannual variability in the circulation dominates over seasonal variability. However, seasonal patterns become predominant for coastal spawning locations, revealing a recurrent shift in the direction of dispersal during the anchovy spawning season.
Survival analysis: Part I — analysis of time-to-event
2018-01-01
Length of time is a variable often encountered during data analysis. Survival analysis provides simple, intuitive results concerning time-to-event for events of interest, which are not confined to death. This review introduces methods of analyzing time-to-event. The Kaplan-Meier survival analysis, log-rank test, and Cox proportional hazards regression modeling method are described with examples of hypothetical data. PMID:29768911
Rayar, Michel; Tron, Camille; Jézéquel, Caroline; Beaurepaire, Jean Marie; Petitcollin, Antoine; Houssel-Debry, Pauline; Camus, Christophe; Verdier, Marie Clémence; Dehlawi, Ammar; Lakéhal, Mohamed; Desfourneaux, Véronique; Meunier, Bernard; Sulpice, Laurent; Bellissant, Eric; Boudjema, Karim; Lemaitre, Florian
2018-03-01
Tacrolimus (TAC) is the cornerstone of immunosuppressive regimen in liver transplantation (LT). Its pharmacokinetics is characterized by a high interpatient and intrapatient variability (IPV) leading to an unpredictable dose-response relationship. The aim of our study was to evaluate the impact of TAC IPV (IPV) on graft and patient outcomes after LT. We retrospectively analyzed 812 LT recipients treated with TAC. The IPV of TAC concentrations was estimated by calculating the coefficient of variation (CV) of whole blood trough concentrations. Patients were categorized in 2 groups: low IPV (CV < 40%) and high IPV (CV ≥ 40%). There were significantly more neurologic complications (31.2% vs 16.6%, P < 0.001), cardiovascular complications (19.7% vs 9.7%, P < 0.001), and acute renal failure requiring dialysis (8.5% vs 2.2%, P < 0.001) in the high CV group than in the low CV group. Moreover, graft survival was significantly poorer in the high CV group (hazard ratio, 1.42; 95% confidence interval, 1.04-1.95; P = 0.03). A pretransplantation elevated Model for End-Stage Liver Disease score (P < 0.001) and Child-Pugh grade (P < 0.001) were identified as risk factors for presenting a high CV. A high CV of TAC concentrations was found to be predictive of TAC-related toxicity and poorer survival.
Govarthanan, Muthusamy; Lee, Gun-Woong; Park, Jung-Hee; Kim, Jae Su; Lim, Sung-Sik; Seo, Sang-Ki; Cho, Min; Myung, Hyun; Kamala-Kannan, Seralathan; Oh, Byung-Taek
2014-08-01
This study was aimed at assess the potential of diazotrophic bacteria, Herbaspirillum sp. GW103, for bioleaching of Cu in mine soil. The strain exhibited resistance to As (550mgL(-1)), Cu (350mgL(-1)), Zn (300mgL(-1)) and Pb (200mgL(-1)). The copper resistance was further confirmed by locating copA and copB genes. The survival of the isolate GW103 during bioleaching was analyzed using green fluorescent protein tagged GW103. Response surface methodology based Box-Behnken design was used to optimize the physical and chemical conditions for Cu bioleaching. Five significant variables (temperature, incubation time, CaCO3, coconut oil cake (COC), agitation rate) were selected for the optimization. Second-order polynomials were established to identify the relationship between Cu bioleaching and variables. The optimal conditions for maximum Cu bioleaching (66%) were 30°C, 60h of incubation with 1.75% of CaCO3 and 3% COC at 140rpm. The results of Cu sequential extraction studies indicated that the isolate GW103 leached Cu from ion-exchangeable, reducible, strong organic and residual fractions. Obtained results point out that the isolate GW103 could be used for bioleaching of Cu from mine soils. Copyright © 2014 Elsevier Ltd. All rights reserved.
Fridman, Masha; Barnes, Vanessa; Whyman, Andrew; Currell, Alex; Bernard, Stephen; Walker, Tony; Smith, Karen L
2007-11-01
This study describes the epidemiology of sudden cardiac arrest patients in Victoria, Australia, as captured via the Victorian Ambulance Cardiac Arrest Register (VACAR). We used the VACAR data to construct a new model of out-of-hospital cardiac arrest (OHCA), which was specified in accordance with observed trends. All cases of cardiac arrest in Victoria that were attended by Victorian ambulance services during the period of 2002-2005. Overall survival to hospital discharge was 3.8% among 18,827 cases of OHCA. Survival was 15.7% among 1726 bystander witnessed, adult cardiac arrests of presumed cardiac aetiology, presenting in ventricular fibrillation or ventricular tachycardia (VF/VT), where resuscitation was attempted. In multivariate logistic regression analysis, bystander CPR, cardiac arrest (CA) location, response time, age and sex were predictors of VF/VT, which, in turn, was a strong predictor of survival. The same factors that affected VF/VT made an additional contribution to survival. However, for bystander CPR, CA location and response time this additional contribution was limited to VF/VT patients only. There was no detectable association between survival and age younger than 60 years or response time over 15min. The new model accounts for relationships among predictors of survival. These relationships indicate that interventions such as reduced response times and bystander CPR act in multiple ways to improve survival.
Martinussen, Torben; Vansteelandt, Stijn; Tchetgen Tchetgen, Eric J; Zucker, David M
2017-12-01
The use of instrumental variables for estimating the effect of an exposure on an outcome is popular in econometrics, and increasingly so in epidemiology. This increasing popularity may be attributed to the natural occurrence of instrumental variables in observational studies that incorporate elements of randomization, either by design or by nature (e.g., random inheritance of genes). Instrumental variables estimation of exposure effects is well established for continuous outcomes and to some extent for binary outcomes. It is, however, largely lacking for time-to-event outcomes because of complications due to censoring and survivorship bias. In this article, we make a novel proposal under a class of structural cumulative survival models which parameterize time-varying effects of a point exposure directly on the scale of the survival function; these models are essentially equivalent with a semi-parametric variant of the instrumental variables additive hazards model. We propose a class of recursive instrumental variable estimators for these exposure effects, and derive their large sample properties along with inferential tools. We examine the performance of the proposed method in simulation studies and illustrate it in a Mendelian randomization study to evaluate the effect of diabetes on mortality using data from the Health and Retirement Study. We further use the proposed method to investigate potential benefit from breast cancer screening on subsequent breast cancer mortality based on the HIP-study. © 2017, The International Biometric Society.
Monceviciūte-Eringiene, E
2005-01-01
In the present review, a new theory that the mechanisms of general evolutionary persistent resistance to damaging factors are closely related to the development of tumour cells is introduced. Evolutionary resistance and its variability have an immense power to drive and control the process of carcinogenesis and the success of microbial and antitumour chemotherapy. First, this phenomenon of adaptation is characteristic of microbial cells whose resistance to antibiotics and other chemotherapeutic drugs is manifested through ATP-dependent transmembrane transporters. The structure and function of some multidrug transporters of resistance are conserved from microorganisms to mammals. When somatic cells are exposed to carcinogens and develop into tumour cells, they also acquire resistance to the toxic effects of carcinogens through these same transmembrane transporters (P-glycoprotein, glutathione S-transferases and other products of evolutionary resistance-related genes arisen for detoxification and exportation of cytotoxic xenobiotics and drugs). Cancerous cells acquire a persistent evolutionary resistance to chemotherapy drugs or irradiation through the same ATP-dependent transporters encountered in prokaryotic and eukaryotic cells. The mechanism of acquired resistance of cells to damaging factors, which becomes manifested during tumorigenic process formation, is a general biological law of primary significance in carcinogenesis. This resistance can be called malignant as, once formed, it does not disappear, as does also a clone of malignant cells. In tumorous cells, the mutagenic processes, morphological and functional modifications are a mechanism of secondary significance in carcinogenesis, contributing to formation of damage-resistant cells. This mechanism characterizes the processes of simplification arising in damage-resistant cells. Such cells acquire parasitic features. To survive under unfavourable conditions, they get adapted as if returning down the evolutionary stairs back to a more primitive stage of atavistic regression, which is characteristic of primitive forms of existence. Therefore they cease obeying the growth-regulating mechanisms in the organism and acquire the potential of unlimited division and accelerated growth (metastases) as do unicellular organisms or their forms resistant to damaging factors in the environment and in the host organism. Thus, cancer is a natural self-protective response of the damaged cells to the biological, physical and chemical damage and oxidative stress. This response has been developed in the process of evolution under the impact of the general biological Darwinian law of nature--to survive through variability and adaptation to the changed environmental conditions. Thus, malignization is the consequence of an evolutionary variety of the general biological resistance of cells to damage and stress in order to survive.
Chao, Tung-Bo; Li, Chien-Feng; Lin, Ching-Yih; Tian, Yu-Feng; Chang, I-Wei; Sheu, Ming-Jen; Lee, Ying-En; Chan, Ti-Chun; He, Hong-Lin
2016-06-01
This study aimed to investigate the prognostic significance of DSG3 and its association with response to neoadjuvant concurrent chemoradiotherapy (CCRT) in rectal cancer. Data mining of a publicly available dataset was performed to find genes associated with CCRT response. Immunohistochemistry was applied to evaluate DSG3 expression. The relationships between DSG3 expression and various clinicopathological parameters and survival were analyzed. The DSG3 gene was significantly associated with CCRT response. The expression of DSG3 negatively correlated with poorer tumor regression (p < 0.001) and had an independent negative impact on disease-specific survival (p = 0.011), local recurrence-free survival (p = 0.031) and metastasis-free survival (p = 0.029). DSG3 was a key prognostic factor and predictor for CCRT response in rectal cancer patients.
Regehr, E.V.; Lunn, N.J.; Amstrup, Steven C.; Stirling, I.
2007-01-01
Some of the most pronounced ecological responses to climatic warming are expected to occur in polar marine regions, where temperature increases have been the greatest and sea ice provides a sensitive mechanism by which climatic conditions affect sympagic (i.e., with ice) species. Population-level effects of climatic change, however, remain difficult to quantify. We used a flexible extension of Cormack-Jolly-Seber capture-recapture models to estimate population size and survival for polar bears (Ursus maritimus), one of the most ice-dependent of Arctic marine mammals. We analyzed data for polar bears captured from 1984 to 2004 along the western coast of Hudson Bay and in the community of Churchill, Manitoba, Canada. The Western Hudson Bay polar bear population declined from 1,194 (95% CI = 1,020-1,368) in 1987 to 935 (95% CI = 794-1,076) in 2004. Total apparent survival of prime-adult polar bears (5-19 yr) was stable for females (0.93; 95% CI = 0.91-0.94) and males (0.90; 95% CI = 0.88-0.91). Survival of juvenile, subadult, and senescent-adult polar bears was correlated with spring sea ice breakup date, which was variable among years and occurred approximately 3 weeks earlier in 2004 than in 1984. We propose that this correlation provides evidence for a causal association between earlier sea ice breakup (due to climatic warming) and decreased polar bear survival. It may also explain why Churchill, like other communities along the western coast of Hudson Bay, has experienced an increase in human-polar bear interactions in recent years. Earlier sea ice breakup may have resulted in a larger number of nutritionally stressed polar bears, which are encroaching on human habitations in search of supplemental food. Because western Hudson Bay is near the southern limit of the species' range, our findings may foreshadow the demographic responses and management challenges that more northerly polar bear populations will experience if climatic warming in the Arctic continues as projected.
Burgos, P I; Vilá, L M; Reveille, J D; Alarcón, G S
2009-12-01
To determine the factors associated with peripheral vascular damage in systemic lupus erythematosus patients and its impact on survival from Lupus in Minorities, Nature versus Nurture, a longitudinal US multi-ethnic cohort. Peripheral vascular damage was defined by the Systemic Lupus International Collaborating Clinics Damage Index (SDI). Factors associated with peripheral vascular damage were examined by univariable and multi-variable logistic regression models and its impact on survival by a Cox multi-variable regression. Thirty-four (5.3%) of 637 patients (90% women, mean [SD] age 36.5 [12.6] [16-87] years) developed peripheral vascular damage. Age and the SDI (without peripheral vascular damage) were statistically significant (odds ratio [OR] = 1.05, 95% confidence interval [CI] 1.01-1.08; P = 0.0107 and OR = 1.30, 95% CI 0.09-1.56; P = 0.0043, respectively) in multi-variable analyses. Azathioprine, warfarin and statins were also statistically significant, and glucocorticoid use was borderline statistically significant (OR = 1.03, 95% CI 0.10-1.06; P = 0.0975). In the survival analysis, peripheral vascular damage was independently associated with a diminished survival (hazard ratio = 2.36; 95% CI 1.07-5.19; P = 0.0334). In short, age was independently associated with peripheral vascular damage, but so was the presence of damage in other organs (ocular, neuropsychiatric, renal, cardiovascular, pulmonary, musculoskeletal and integument) and some medications (probably reflecting more severe disease). Peripheral vascular damage also negatively affected survival.
Witlin, A G; Saade, G R; Mattar, F; Sibai, B M
2000-03-01
We sought to characterize predictors of neonatal outcome in women with severe preeclampsia or eclampsia who were delivered of their infants preterm. We performed a retrospective analysis of 195 pregnancies delivered between 24 and 33 weeks' gestation because of severe preeclampsia or eclampsia. Multiple logistic regression and univariate chi(2) analysis were performed for the dependent outcome variables of survival and respiratory distress syndrome by use of independent fetal and maternal variables. A P value of <.05 was considered significant. In the multivariate analysis, respiratory distress syndrome was inversely related to gestational age at delivery (P =.0018) and directly related to cesarean delivery (P =.02), whereas survival was directly related to birth weight (P =.00025). There was no correlation in the multivariate analysis between respiratory distress syndrome or survival and corticosteroid use, composite neonatal morbidity, mean arterial pressure, eclampsia, or abruptio placentae. In the univariate analysis respiratory distress syndrome was associated with cesarean delivery (odds ratio, 7.19; 95% confidence interval, 2. 91-18.32). The incidence of intrauterine growth restriction increased as gestational age advanced. Furthermore, intrauterine growth restriction decreased survival in both the multivariate (P =. 038; odds ratio, 13.2; 95% confidence interval, 1.16-151.8) and univariate (P =.001; odds ratio, 5.88; 95% confidence interval, 1. 81-19.26) analyses. The presence of intrauterine growth restriction adversely affected survival independently of other variables. Presumed intrauterine stress, as reflected by the severity of maternal disease, did not improve neonatal outcome.
Facciorusso, Antonio; Del Prete, Valentina; Antonino, Matteo; Neve, Viviana; Amoruso, Annabianca; Crucinio, Nicola; Di Leo, Alfredo; Barone, Michele
2015-10-01
Survival estimates are commonly reported as survival from the first observation, but future survival probability changes based on the survival time already accumulated after therapy, otherwise known as conditional survival (CS). The aim of the study was to describe CS according to different prognostic variables in hepatocellular carcinoma (HCC) patients treated with radiofrequency ablation (RFA). Data on 125 very early/early HCC patients treated with RFA between 1999 and 2007 were analyzed. Actuarial survival estimates were computed by means of Kaplan-Meier method and compared by log-rank test. The 5-year CS was calculated with stratification by several predictors for patients who had already survived up to 5 years from diagnosis. Median overall survival (OS) was 72 months (95% confidence interval [CI], 58-86). Age, Child-Pugh (CP), α-fetoprotein (AFP), Cancer of the Liver Italian Program (CLIP) score and type of recurrence (early vs late) were significant predictors of OS. The 5-year CS rates of the entire study cohort assessed at 1, 2, 3 and 5 years from the treatment were 49%, 48%, 30% and 34%, respectively. Subgroup analysis confirmed age and CP as significant predictors of CS at all time points, while the CS of subgroups stratified by AFP and CLIP did not differ significantly from the 3rd year after RFA onward, as more advanced patients had probably escaped early recurrence. CS analysis showed that the impact of different variables influencing OS is not linear over time after RFA. Information derived from the study can improve the current management of HCC patients. © 2014 The Japan Society of Hepatology.
Interleukin-6 predicts recurrence and survival among head and neck cancer patients.
Duffy, Sonia A; Taylor, Jeremy M G; Terrell, Jeffrey E; Islam, Mozaffarul; Li, Yun; Fowler, Karen E; Wolf, Gregory T; Teknos, Theodoros N
2008-08-15
Increased pretreatment serum interleukin (IL)-6 levels among patients with head and neck squamous cell carcinoma (HNSCC) have been shown to correlate with poor prognosis, but sample sizes in prior studies have been small and thus unable to control for other known prognostic variables. A longitudinal, prospective cohort study determined the correlation between pretreatment serum IL-6 levels, and tumor recurrence and all-cause survival in a large population (N = 444) of previously untreated HNSCC patients. Control variables included age, sex, smoking, cancer site and stage, and comorbidities. Kaplan-Meier plots and univariate and multivariate Cox proportional hazards models were used to study the association between IL-6 levels, control variables, and time to recurrence and survival. The median serum IL-6 level was 13 pg/mL (range, 0-453). The 2-year recurrence rate was 35.2% (standard error, 2.67%). The 2-year death rate was 26.5% (standard error, 2.26%). Multivariate analyses showed that serum IL-6 levels independently predicted recurrence at significant levels [hazard ratio (HR) = 1.32; 95% confidence interval (CI), 1.11 to 1.58; P = .002] as did cancer site (oral/sinus). Serum IL-6 level was also a significant independent predictor of poor survival (HR = 1.22; 95% CI, 1.02 to 1.46; P = .03), as were older age, smoking, cancer site (oral/sinus), higher cancer stage, and comorbidities. Pretreatment serum IL-6 could be a valuable biomarker for predicting recurrence and overall survival among HNSCC patients. Using IL-6 as a biomarker for recurrence and survival may allow for earlier identification and treatment of disease relapse. 2008 American Cancer Society
Bygren, L. O.; Konlaan, B. B.; Johansson, S. E.
1996-01-01
OBJECTIVES: To investigate the possible influence of attendance at cultural events, reading books or periodicals, making music or singing in a choir as determinants for survival. DESIGN: A simple random sample was drawn of 15,198 individuals aged 16-74 years. Of these, 85% (12,982) were interviewed by trained non-medical interviewers between 1982 and 1983 about cultural activities. They were followed up with respect to survival until 31 December 1991. SETTING: Swedish interview survey of living conditions comprising a random sample of the adult Swedish population. SUBJECTS: 12,675 people interviewed between 1982 and 1983. MAIN OUTCOME MEASURES: Survival of subjects after controlling for eight confounding variables: age, sex, education level, income, long term disease, social network, smoking, and physical exercise. RESULTS: 6,301 men and 6,374 women were followed up; 533 men and 314 women died during this period. The control variables influenced survival in the expected directions except for social network for men; a significant negative effective was found when the analysis was made separately for men and women. We found an influence on mortality when the eight control variables were controlled for in people who rarely attended events compared with those attending most often, the relative risk being 1.57 (95% confidence interval 1.18 to 2.09). CONCLUSION: Attendance at cultural events may have a positive influence on survival. Long term follow up of large samples with confounders that are well controlled for and with the cultural stimulation more highly specified should be used to try to falsify the hypothesis before experiments start. PMID:8990990
Querin, G; El Mendili, M M; Lenglet, T; Delphine, S; Marchand-Pauvert, V; Benali, H; Pradat, P-F
2017-08-01
Assessing survival is a critical issue in patients with amyotrophic lateral sclerosis (ALS). Neuroimaging seems to be promising in the assessment of disease severity and several studies also suggest a strong relationship between spinal cord (SC) atrophy described by magnetic resonance imaging (MRI) and disease progression. The aim of the study was to determine the predictive added value of multimodal SC MRI on survival. Forty-nine ALS patients were recruited and clinical data were collected. Patients were scored on the Revised ALS Functional Rating Scale and manual muscle testing. They were followed longitudinally to assess survival. The cervical SC was imaged using the 3 T MRI system. Cord volume and cross-sectional area (CSA) at each vertebral level were computed. Diffusion tensor imaging metrics were measured. Imaging metrics and clinical variables were used as inputs for a multivariate Cox regression survival model. On building a multivariate Cox regression model with clinical and MRI parameters, fractional anisotropy, magnetization transfer ratio and CSA at C2-C3, C4-C5, C5-C6 and C6-C7 vertebral levels were significant. Moreover, the hazard ratio calculated for CSA at the C3-C4 and C5-C6 levels indicated an increased risk for patients with SC atrophy (respectively 0.66 and 0.68). In our cohort, MRI parameters seem to be more predictive than clinical variables, which had a hazard ratio very close to 1. It is suggested that multimodal SC MRI could be a useful tool in survival prediction especially if used at the beginning of the disease and when combined with clinical variables. To validate it as a biomarker, confirmation of the results in bigger independent cohorts of patients is warranted. © 2017 EAN.
Sebastián Sebastián, C; García Mur, C; Cruz Ciria, S; Rosero Cuesta, D S; Gros Bañeres, B
2016-01-01
To analyze what factors in magnetic resonance imaging (MRI) and histological study of triple-negative breast cancers are related to tumor recurrence and to shorter disease-free survival. To analyze survival and recurrence in function of the presence of an in situ component. This was a retrospective study of MRI staging examinations in 122 women with triple-negative breast cancer done from 2007 through 2014. In the MRI, we evaluated morphological variables (size, margins, morphology, internal signal in T2-weighted sequences) and dynamic variables (perfusion and diffusion). In the histological study, we evaluated Ki67, p53, CK5/6, nuclear grade, and Scarff-Bloom grade, as well as the presence of an in situ component and tumor grade (high grade or not high grade). We compared the variables between patients with tumor recurrence and those without, and we conducted a survival analysis. Non-nodular enhancement was more common in patients with tumor recurrence (p=0.038) and was associated with shorter disease-free survival (p=0.023). Neither diffusion restriction (p=0.079) nor ki67 (p=0.052) was associated with a worse prognosis. An in situ component was detected in 44% of triple-negative tumors, and a greater proportion of patients in the group with tumor recurrence had an in situ component; however, the presence of an in situ component was not associated with shorter survival (p = 0.185). Non-nodular enhancement was associated with a worse prognosis. Diffusion restriction, ki67, and the presence of an in situ component were not associated with shorter disease-free survival. Copyright © 2016 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.
Review of in vivo studies of dimethyl sulfoxide cryopreserved platelets.
Slichter, Sherrill J; Jones, Melinh; Ransom, Janet; Gettinger, Irena; Jones, Mary Kay; Christoffel, Todd; Pellham, Esther; Bailey, S Lawrence; Corson, Jill; Bolgiano, Doug
2014-10-01
A literature review was conducted to assess the efficacy and safety of dimethyl sulfoxide (DMSO) cryopreserved platelets for potential military use. In vivo DMSO cryopreserved platelet studies published between 1972 and June of 2013 were reviewed. Assessed were the methods of cryopreservation, posttransfusion platelet responses, prevention or control of bleeding, and adverse events. Using the Department of Defense's preferred 6% DMSO cryopreservation method with centrifugation to remove the DMSO plasma before freezing at -65°C and no postthaw wash, mean radiolabeled platelet recoveries in 32 normal subjects were 33% ± 10% (52% ± 12% of the same subject's fresh platelet recoveries), and survivals were 7.5 ± 1.2 days (89% ± 15% of fresh platelet survivals). Using a variety of methods to freeze autologous platelets from 178 normal subjects, mean radiolabeled platelet recoveries were consistently 39% ± 9%, and survivals, 7.4 ± 1.4 days. More than 3000 cryopreserved platelet transfusions were given to 1334 patients. There were 19 hematology/oncology patient studies, and, in 9, mean 1-hour corrected count increments were 11 100 ± 3600 (range, 5700-15 800) after cryopreserved autologous platelet transfusions. In 5 studies, bleeding times improved after transfusion; in 3, there was either no improvement or a variable response. In 4 studies, there was immediate cessation of bleeding after transfusion; in 3 studies, patients being supported only with cryopreserved platelets had no bleeding. In 1 cardiopulmonary bypass study, cryopreserved platelets resulted in significantly less bleeding vs standard platelets. In 3 trauma studies, cryopreserved platelets were hemostatically effective. No significant adverse events were reported in any study. In summary, cryopreserved platelets have platelet recoveries that are about half of fresh platelets, but survivals are only minimally reduced. The platelets appear hemostatically effective and have no significant adverse events. Copyright © 2014 Elsevier Inc. All rights reserved.
Bashan, Yoav; Salazar, Bernardo G; Moreno, Manuel; Lopez, Blanca R; Linderman, Robert G
2012-07-15
Restoration of highly eroded desert land was attempted in the southern Sonoran Desert that had lost its natural capacity for self-revegetation. In six field experiments, the fields were planted with three native leguminous trees: mesquite amargo Prosopis articulata, and yellow and blue palo verde Parkinsonia microphylla and Parkinsonia florida. Restoration included inoculation with two of plant growth-promoting bacteria (PGPB; Azospirillum brasilense and Bacillus pumilus), native arbuscular mycorrhizal (AM) fungi, and small quantities of compost. Irrigation was applied, when necessary, to reach a rainy year (300 mm) of the area. The plots were maintained for 61 months. Survival of the trees was marginally affected by all supplements after 30 months, in the range of 60-90%. This variation depended on the plant species, where all young trees were established after 3 months. Plant density was a crucial variable and, in general, low plant density enhanced survival. High planting density was detrimental. Survival significantly declined in trees 61 months after planting. No general response of the trees to plant growth-promoting microorganisms and compost was found. Mesquite amargo and yellow palo verde responded well (height, number of branches, and diameter of the main stem) to inoculation with PGPB, AM fungi, and compost supplementation after three months of application. Fewer positive effects were recorded after 30 months. Blue palo verde did not respond to most treatments and had the lowest survival. Specific plant growth parameters were affected to varying degrees to inoculations or amendments, primarily depending on the tree species. Some combinations of tree/inoculant/amendment resulted in small negative effects or no response when measured after extended periods of time. Using native leguminous trees, this study demonstrated that restoration of severely eroded desert lands was possible. Copyright © 2012 Elsevier Ltd. All rights reserved.
Parametric analysis for matched pair survival data.
Manatunga, A K; Oakes, D
1999-12-01
Hougaard's (1986) bivariate Weibull distribution with positive stable frailties is applied to matched pairs survival data when either or both components of the pair may be censored and covariate vectors may be of arbitrary fixed length. When there is no censoring, we quantify the corresponding gain in Fisher information over a fixed-effects analysis. With the appropriate parameterization, the results take a simple algebraic form. An alternative marginal ("independence working model") approach to estimation is also considered. This method ignores the correlation between the two survival times in the derivation of the estimator, but provides a valid estimate of standard error. It is shown that when both the correlation between the two survival times is high, and the ratio of the within-pair variability to the between-pair variability of the covariates is high, the fixed-effects analysis captures most of the information about the regression coefficient but the independence working model does badly. When the correlation is low, and/or most of the variability of the covariates occurs between pairs, the reverse is true. The random effects model is applied to data on skin grafts, and on loss of visual acuity among diabetics. In conclusion some extensions of the methods are indicated and they are placed in a wider context of Generalized Estimation Equation methodology.
Wolfensberger, M
1992-01-01
One of the major short comings of the traditional TNM system is its limited potential for prognostication. With the development of multifactorial analysis techniques, such as Cox's proportional hazards model, it has become possible to simultaneously evaluate a large number of prognostic variables. Cox's model allows both the identification of prognostically relevant variables and the quantification of their prognostic influence. These characteristics make it a helpful tool for analysis as well as for prognostication. The goal of the present study was to develop a prognostic index for patients with carcinoma of the upper aero-digestive tract which makes use of all prognostically relevant variables. To accomplish this, the survival data of 800 patients with squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx or larynx were analyzed. Sixty-one variables were screened for prognostic significance; of these only 19 variables (including age, tumor location, T, N and M stages, resection margins, capsular invasion of nodal metastases, and treatment modality) were found to significantly correlate with prognosis. With the help of Cox's equation, a prognostic index (PI) was computed for every combination of prognostic factors. To test the proposed model, the prognostic index was applied to 120 patients with carcinoma of the oral cavity or oropharynx. A comparison of predicted and observed survival showed good overall correlation, although actual survival tended to be better than predicted.
Zareen, Nusrat; Khan, Muhammad Yunus; Minhas, Liaqat Ali
2009-01-01
The possible adverse effects of Electromagnetic Fields (EMFs) emitted from mobile phones present a major public concern today. Some studies indicate EMFs effects on genes, free radical production, immunological and carcinogenic effects. On the other hand there are studies which do not support the hypothesis of any biological impacts of EMFs. This study was designed to observe the effects of mobile phone induced EMFs on survival and general growth and development of chick embryo, investigating dose-response relationship if any. This was an experimental study in which developing chick embryos were exposed to different doses of mobile phone induced EMFs. For this purpose a mobile phone was placed in the incubator in the centre of fertilised eggs in silent ringing mode and was 'rung' upon from any other line or cell phone. After incubation for 10 or 15 days the eggs were opened and the developmental mile-stones of the surviving embryos were compared with the non exposed subgroup. EMFs exposure significantly decreased the survivability of the chick embryos. The lower doses of EMFs caused growth retardation. However, this effect of growth retardation reallocated to partial growth enhancement on increasing the dose of EMFs and shifted over to definite growth enhancement on further raising the dose. There is an adverse effect of EMFs exposure on embryo survivability. Chick embryos developmental process is influenced by EMFs. However, these effects are variable depending upon the dose of EMFs exposure.
Scott, H. Morgan; Soskolne, Colin L.; Lissemore, Kerry D.; Martin, S. Wayne; Shoukri, Mohamed M.; Coppock, Robert W.; Guidotti, Tee L.
2003-01-01
This paper describes the results of an investigation into the effects of air emissions from sour gas processing plants on indices of retainment or survival of adult female dairy cattle on farms in Alberta; namely, the productive lifespan of individual animals, and annual herd-level risks for culling and mortality. Using a geographical information system, 2 dispersion models — 1 simple and 1 complex — were used to assess historical exposures to sour gas emissions at 1382 dairy farm sites from 1985 through to 1994. Multivariable survival models, adjusting for the dependence of survival responses within a herd over time, as well as potential confounding variables, were utilized to determine associations between sour gas exposure estimates and the time from the first calving date to either death or culling of 150 210 dairy cows. Generalized linear models were used to model the relationship between herd-level risks for culling and mortality and levels of sour gas exposure. No significant (P < 0.05) associations were found with the time to culling (n = 70 052). However, both dispersion model exposure estimates were significantly associated (P < 0.05) with a decreased hazard for mortality; that is, in cases where cattle had died on-farm (n = 8743). There were no significant associations (P > 0.05) between herd culling risks and the 2 dispersion model exposure estimates. There was no measurable impact of plant emissions on the annual herd risk of mortality. PMID:12528823
Linking vital rates to invasiveness of a perennial herb.
Ramula, Satu
2014-04-01
Invaders generally show better individual performance than non-invaders and, therefore, vital rates (survival, growth, fecundity) could potentially be used to predict species invasiveness outside their native range. Comparative studies have usually correlated vital rates with the invasiveness status of species, while few studies have investigated them in relation to population growth rate. Here, I examined the influence of five vital rates (plant establishment, survival, growth, flowering probability, seed production) and their variability (across geographic regions, habitat types, population sizes and population densities) on population growth rate (λ) using data from 37 populations of an invasive, iteroparous herb (Lupinus polyphyllus) in a part of its invaded range in Finland. Variation in vital rates was often related to habitat type and population density. The performance of the populations varied from declining to rapidly increasing independently of habitat type, population size or population density, but differed between regions. The population growth rate increased linearly with plant establishment, and with the survival and growth of vegetative individuals, while the survival of flowering individuals and annual seed production were not related to λ. The vital rates responsible for rapid population growth varied among populations. These findings highlight the importance of both regional and local conditions to plant population dynamics, demonstrating that individual vital rates do not necessarily correlate with λ. Therefore, to understand the role of individual vital rates in a species ability to invade, it is necessary to quantify their effect on population growth rate.
Yin, Ben-feng; Zhang, Yuan-ming; Lou, An-ru
2017-01-01
Moss crusts play important roles in biological soil crusts biomass and soil surface stabilization. However, because of increasingly intensive human activities, especially grazing, the growth and survival of shrubs are seriously threatened. This study aimed to test whether the presence of shrubs affects the physiological state of the bryophyte Syntrichia caninervis Mitt. in this desert ecosystem. We simulated animal-grazed shrubs at three levels in the Gurbantunggut Desert and compared these simulations to exposed areas, measuring the indicators of growth and stress tolerance exhibited by bryophytes. The results showed that the removal of shrubs significantly decreased chlorophyll fluorescence activity and soluble protein content in S. caninervis, especially under the total shrub removal treatment. The ratio between the total removal of shrubs and other treatments in antioxidative enzymes and in osmotic adjustment substances of S. caninervis exhibited two types of responses. With the exception of malonyldialdehyde (MDA) and superoxide dismutase (SOD), the variables examined fitted as downward parabolic then upward parabolic temporal dynamics. The removal of shrubs is harmful to the survival of S.caninervis. In resource-constrained conditions, SOD is an important antioxidant enzyme that of peroxidase (POD), catalase (CAT) and osmotic adjustment substances, for S. caninervis survival. PMID:28374741
Yin, Ben-Feng; Zhang, Yuan-Ming; Lou, An-Ru
2017-04-04
Moss crusts play important roles in biological soil crusts biomass and soil surface stabilization. However, because of increasingly intensive human activities, especially grazing, the growth and survival of shrubs are seriously threatened. This study aimed to test whether the presence of shrubs affects the physiological state of the bryophyte Syntrichia caninervis Mitt. in this desert ecosystem. We simulated animal-grazed shrubs at three levels in the Gurbantunggut Desert and compared these simulations to exposed areas, measuring the indicators of growth and stress tolerance exhibited by bryophytes. The results showed that the removal of shrubs significantly decreased chlorophyll fluorescence activity and soluble protein content in S. caninervis, especially under the total shrub removal treatment. The ratio between the total removal of shrubs and other treatments in antioxidative enzymes and in osmotic adjustment substances of S. caninervis exhibited two types of responses. With the exception of malonyldialdehyde (MDA) and superoxide dismutase (SOD), the variables examined fitted as downward parabolic then upward parabolic temporal dynamics. The removal of shrubs is harmful to the survival of S.caninervis. In resource-constrained conditions, SOD is an important antioxidant enzyme that of peroxidase (POD), catalase (CAT) and osmotic adjustment substances, for S. caninervis survival.
de Miranda, Marcos Lopes; Pereira, Sandra J; Santos, Ana O M T; Villela, Nivaldo R; Kraemer-Aguiar, Luiz Guilherme; Bouskela, Eliete
2015-01-01
Apart from its inotropic property, milrinone has vasodilator, anti-inflammatory and antithrombotic effects that could assist in the reversal of septic microcirculatory changes. This paper investigates the effects of milrinone on endotoxemia-related microcirculatory changes and compares them to those observed with the use of norepinephrine. After skinfold chamber implantation procedures and endotoxemia induction by intravenous Escherichia coli lipopolysaccharide administration (2 mg.kg-1), male golden Syrian hamsters were treated with two regimens of intravenous milrinone (0.25 or 0.5 μg.kg-1.min-1). Intravital microscopy of skinfold chamber preparations allowed quantitative analysis of microvascular variables. Macro-hemodynamic, biochemical, and hematological parameters and survival rate were also analyzed. Endotoxemic non-treated animals, endotoxemic animals treated with norepinephrine (0.2 μg.kg-1.min-1), and non-endotoxemic hamsters served as controls. Milrinone (0.5 μg.kg-1.min-1) was effective in reducing lipopolysaccharide-induced arteriolar vasoconstriction, capillary perfusion deficits, and inflammatory response, and in increasing survival. Norepinephrine treated animals showed the best mean arterial pressure levels but the worst functional capillary density values among all endotoxemic groups. Our data suggests that milrinone yielded protective effects on endotoxemic animals' microcirculation, showed anti-inflammatory properties, and improved survival. Norepinephrine did not recruit the microcirculation nor demonstrated anti-inflammatory effects.
A meta-analysis of the effects of exposure to microplastics on fish and aquatic invertebrates.
Foley, Carolyn J; Feiner, Zachary S; Malinich, Timothy D; Höök, Tomas O
2018-08-01
Microplastics are present in aquatic ecosystems the world over and may influence the feeding, growth, reproduction, and survival of freshwater and marine biota; however, the extent and magnitude of potential effects of microplastics on aquatic organisms is poorly understood. In the current study, we conducted a meta-analysis of published literature to examine impacts of exposure to microplastics on consumption (and feeding), growth, reproduction, and survival of fish and aquatic invertebrates. While we did observe within-taxa negative effects for all four categories of responses, many of the effects summarized in our study were neutral, indicating that the effects of exposure to microplastics are highly variable across taxa. The most consistent effect was a reduction in consumption of natural prey when microplastics were present. For some taxa, negative effects on growth, reproduction and even survival were also evident. Organisms that serve as prey to larger predators, e.g., zooplankton, may be particularly susceptible to negative impacts of exposure to microplastic pollution, with potential for ramifications throughout the food web. Future work should focus on whether microplastics may be affecting aquatic organisms more subtly, e.g., by influencing exposure to contaminants and pathogens, or by acting at a molecular level. Copyright © 2018 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Yin, Ben-Feng; Zhang, Yuan-Ming; Lou, An-Ru
2017-04-01
Moss crusts play important roles in biological soil crusts biomass and soil surface stabilization. However, because of increasingly intensive human activities, especially grazing, the growth and survival of shrubs are seriously threatened. This study aimed to test whether the presence of shrubs affects the physiological state of the bryophyte Syntrichia caninervis Mitt. in this desert ecosystem. We simulated animal-grazed shrubs at three levels in the Gurbantunggut Desert and compared these simulations to exposed areas, measuring the indicators of growth and stress tolerance exhibited by bryophytes. The results showed that the removal of shrubs significantly decreased chlorophyll fluorescence activity and soluble protein content in S. caninervis, especially under the total shrub removal treatment. The ratio between the total removal of shrubs and other treatments in antioxidative enzymes and in osmotic adjustment substances of S. caninervis exhibited two types of responses. With the exception of malonyldialdehyde (MDA) and superoxide dismutase (SOD), the variables examined fitted as downward parabolic then upward parabolic temporal dynamics. The removal of shrubs is harmful to the survival of S.caninervis. In resource-constrained conditions, SOD is an important antioxidant enzyme that of peroxidase (POD), catalase (CAT) and osmotic adjustment substances, for S. caninervis survival.
Villanueva, Paola A.; Lopez, Jorge; Torres, Rodrigo; Navarro, Jorge M.; Bacigalupe, Leonardo D.
2017-01-01
Phenotypic plasticity is expected to play a major adaptive role in the response of species to ocean acidification (OA), by providing broader tolerances to changes in pCO2 conditions. However, tolerances and sensitivities to future OA may differ among populations within a species because of their particular environmental context and genetic backgrounds. Here, using the climatic variability hypothesis (CVH), we explored this conceptual framework in populations of the sea urchin Loxechinus albus across natural fluctuating pCO2/pH environments. Although elevated pCO2 affected the morphology, physiology, development and survival of sea urchin larvae, the magnitude of these effects differed among populations. These differences were consistent with the predictions of the CVH showing greater tolerance to OA in populations experiencing greater local variation in seawater pCO2/pH. Considering geographical differences in plasticity, tolerances and sensitivities to increased pCO2 will provide more accurate predictions for species responses to future OA. PMID:28179409
Gaitán-Espitia, Juan Diego; Villanueva, Paola A; Lopez, Jorge; Torres, Rodrigo; Navarro, Jorge M; Bacigalupe, Leonardo D
2017-02-01
Phenotypic plasticity is expected to play a major adaptive role in the response of species to ocean acidification (OA), by providing broader tolerances to changes in p CO 2 conditions. However, tolerances and sensitivities to future OA may differ among populations within a species because of their particular environmental context and genetic backgrounds. Here, using the climatic variability hypothesis (CVH), we explored this conceptual framework in populations of the sea urchin Loxechinus albus across natural fluctuating p CO 2 /pH environments. Although elevated p CO 2 affected the morphology, physiology, development and survival of sea urchin larvae, the magnitude of these effects differed among populations. These differences were consistent with the predictions of the CVH showing greater tolerance to OA in populations experiencing greater local variation in seawater p CO 2 /pH. Considering geographical differences in plasticity, tolerances and sensitivities to increased p CO 2 will provide more accurate predictions for species responses to future OA. © 2017 The Author(s).
2014-01-01
Response surface methodology using a face-centered cube design was used to describe and predict spore inactivation of Bacillus anthracis ∆Sterne and Bacillus thuringiensis Al Hakam spores after exposure of six spore-contaminated materials to hot, humid air. For each strain/material pair, an attempt was made to fit a first or second order model. All three independent predictor variables (temperature, relative humidity, and time) were significant in the models except that time was not significant for B. thuringiensis Al Hakam on nylon. Modeling was unsuccessful for wiring insulation and wet spores because there was complete spore inactivation in the majority of the experimental space. In cases where a predictive equation could be fit, response surface plots with time set to four days were generated. The survival of highly purified Bacillus spores can be predicted for most materials tested when given the settings for temperature, relative humidity, and time. These predictions were cross-checked with spore inactivation measurements. PMID:24949256
Prevention of lyme disease: promising research or sisyphean task?
Krupka, Michal; Zachova, Katerina; Weigl, Evzen; Raska, Milan
2011-08-01
Borrelia burgdorferi sensu lato (Spirochaetes) is a group of at least 12 closely related species, some of which are responsible for chronic zoonotic infection that may cause Lyme disease. The only experimentally confirmed vector transmitting Borrelia to mammals is the Ixodes ticks. Borrelia is a highly adapted pathogen that can survive in the host organism in spite of the intense immune responses. Some patients have chronic long-lasting complications despite antibiotic therapy, probably due to adverse effects of the immune responses. A preventive vaccine against this bacterium has not been available due to the relatively broad spectrum and antigenic variability of Borrelia-surface lipoproteins and the different epitope recognition by experimental animals and humans. Although a human vaccine was marketed in the USA, it has been already pulled off the market. In addition, this vaccine was effective only in the USA, where the only pathogenic species is B. burgdorferi sensu stricto. Recent data indicate that a broadly effective vaccine will to be composed of a mixture of several antigens or multiple epitopes.
Brain connectivity reflects human aesthetic responses to music.
Sachs, Matthew E; Ellis, Robert J; Schlaug, Gottfried; Loui, Psyche
2016-06-01
Humans uniquely appreciate aesthetics, experiencing pleasurable responses to complex stimuli that confer no clear intrinsic value for survival. However, substantial variability exists in the frequency and specificity of aesthetic responses. While pleasure from aesthetics is attributed to the neural circuitry for reward, what accounts for individual differences in aesthetic reward sensitivity remains unclear. Using a combination of survey data, behavioral and psychophysiological measures and diffusion tensor imaging, we found that white matter connectivity between sensory processing areas in the superior temporal gyrus and emotional and social processing areas in the insula and medial prefrontal cortex explains individual differences in reward sensitivity to music. Our findings provide the first evidence for a neural basis of individual differences in sensory access to the reward system, and suggest that social-emotional communication through the auditory channel may offer an evolutionary basis for music making as an aesthetically rewarding function in humans. © The Author (2016). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.
Atcheson, Margaret E.; Myers, Katherine W.; Beauchamp, David A.; Mantua, Nathan J.
2012-01-01
Energetic responses of steelhead Oncorhynchus mykiss to climate-driven changes in marine conditions are expected to affect the species’ ocean distribution, feeding, growth, and survival. With a unique 18-year data series (1991–2008) for steelhead sampled in the open ocean, we simulated interannual variation in prey consumption and growth efficiency of steelhead using a bioenergetics model to evaluate the temperature-dependent growth response of steelhead to past climate events and to estimate growth potential of steelhead under future climate scenarios. Our results showed that annual ocean growth of steelhead is highly variable depending on prey quality, consumption rates, total consumption, and thermal experience. At optimal growing temperatures, steelhead can compensate for a low-energy diet by increasing consumption rates and consuming more prey, if available. Our findings suggest that steelhead have a narrow temperature window in which to achieve optimal growth, which is strongly influenced by climate-driven changes in ocean temperature.
Dale, O T; Sood, S; Shah, K A; Han, C; Rapozo, D; Mehanna, H; Winter, S C
2016-11-01
This study investigated long-term survival outcomes in surgically treated oropharyngeal cancer patients with known human papilloma virus status. A case note review was performed of all patients undergoing primary surgery for oropharyngeal cancer in a single centre over a 10-year period. Human papilloma virus status was determined via dual modality testing. Associations between clinicopathological variables and survival were identified using a log-rank test. Of the 107 cases in the study, 40 per cent (n = 41) were human papilloma virus positive. The positive and negative predictive values of p16 immunohistochemistry for human papilloma virus status were 57 per cent and 100 per cent, respectively. At a mean follow up of 59.5 months, 5-year overall and disease-specific survival estimates were 78 per cent and 69 per cent, respectively. Human papilloma virus status (p = 0.014), smoking status (p = 0.021) and tumour stage (p = 0.03) were significant prognostic indicators. The long-term survival rates in surgically treated oropharyngeal cancer patients were comparable to other studies. Variables including human papilloma virus status and tumour stage were associated with survival in patients treated with primary surgery; however, nodal stage and presence of extracapsular spread were non-prognostic.
Evaluating disease management program effectiveness: an introduction to survival analysis.
Linden, Ariel; Adams, John L; Roberts, Nancy
2004-01-01
Currently, the most widely used method in the disease management industry for evaluating program effectiveness is the "total population approach." This model is a pretest-posttest design, with the most basic limitation being that without a control group, there may be sources of bias and/or competing extraneous confounding factors that offer plausible rationale explaining the change from baseline. Survival analysis allows for the inclusion of data from censored cases, those subjects who either "survived" the program without experiencing the event (e.g., achievement of target clinical levels, hospitalization) or left the program prematurely, due to disenrollement from the health plan or program, or were lost to follow-up. Additionally, independent variables may be included in the model to help explain the variability in the outcome measure. In order to maximize the potential of this statistical method, validity of the model and research design must be assured. This paper reviews survival analysis as an alternative, and more appropriate, approach to evaluating DM program effectiveness than the current total population approach.
Gold, Philip J.; Goldman, Bryan; Iqbal, Syma; Leichman, Lawrence P.; Zhang, Wu; Lenz, Heinz-Josef; Blanke, Charles D.
2010-01-01
Introduction Esophageal adenocarcinomas commonly express the Epidermal Growth Factor Receptor (EGFR). This trial assessed the six month overall survival probability in metastatic esophageal cancer patients treated with cetuximab as second line therapy. Methods This was a multicenter, open-label phase II study of single agent cetuximab for metastatic esophageal adenocarcinoma patients who failed one prior chemotherapy regimen. Adequate organ function and Zubrod performance status of 0-2 were required. Patients received cetuximab 400mg/m2 IV on week one, and 250 mg/m2 IV weekly thereafter. The primary objective was to determine 6 month overall survival. Secondary endpoints included progression-free survival, response rate, and toxicity. Tumor tissue was collected for correlative studies. Results Sixty-three patients were registered, with 8 ineligible or never treated. Fifty-five eligible patients (male=49, female=6; median age=61.2 years [range 30.7-88.5]) were enrolled. Twenty patients survived > 6 months for a 6-month overall survival rate of 36% (95% CI: 24%, 50%). The median overall survival was 4.0 months (95% CI: 3.2, 5.9). Median progression-free survival was 1.8 months (95% CI: 1.7, 1.9). One partial response and 2 unconfirmed partial responses were observed. Two patients experienced grade 4 fatigue. There was one treatment-related death due to pneumonitis. Germline polymorphisms of EGFR, EGF, IL-8, COX-2, VEGF, CCND1, NRP1 and Kras mutational status were not associated with response or survival. Conclusions The 6-month overall survival rate of 36% observed on this study failed to meet the primary survival objective. Thus, cetuximab alone cannot be recommended in the second-line treatment of metastatic esophageal cancer. PMID:20631636
Fertility response to child survival in Nigeria: an analysis of microdata from Bendel State.
Okojie, C E
1991-01-01
A researcher used data on 2145 15-50 year old ever married women from a 1985 fertility survey in Bendel State, Nigeria to estimate fertility response to own child survival. For 35-50 year old women, fertility fell steadily with higher levels of education even when she controlled for the age education interaction. Education did not have a significant effect for younger women, however. Yet husband's education had a significant positive effect on fertility. Further the proportion of surviving children (the survival ratio) was negatively associated with fertility for all women and for all age groups, especially 25-34 year old women. The fact that the survival ratio was still negatively associated with fertility for women =or+ 35 years old suggested that women adjusted to their own experience of child mortality by the end of childbearing. Further it implied that a rise in child survival would inevitably lower fertility. The researcher then compared the fertility behavior of rural and urban women in terms of child survival. Since the survival rate was significant for rural women, it is suggested that own child survival had a considerable influence on fertility behavior. For urban women, however, it was significant perhaps because access to water did not differ much in the urban sample or account for child mortality. Own child mortality was 36.7% for rural women compared to 23.7% for urban women. The stronger reproductive response among older women and among rural women implied that behavior factors had a stronger role in the reproductive response than biological factors. These results suggested that own child mortality and community mortality may be more important than national average mortality. Further research on aggregate mortality trends and individual child survival experience and their link to individual reproductive behavior in Nigeria are needed.
Long-term survival based on pathologic response to neoadjuvant therapy in esophageal cancer.
Tiesi, Gregory; Park, Wungki; Gunder, Meredith; Rubio, Gustavo; Berger, Michael; Ardalan, Bach; Livingstone, Alan; Franceschi, Dido
2017-08-01
Neoadjuvant treatment is standard for locally advanced esophageal cancer. However, whether the addition of radiation to neoadjuvant regimen improves survival remains unclear. The aim of this study was to compare survival in locally advanced esophageal cancer treated with neoadjuvant chemotherapy versus chemoradiation. A prospectively maintained database of esophagectomies (1999-2012) was analyzed. We identified 297 patients with locally advanced esophageal cancer that underwent either neoadjuvant chemotherapy (n = 231) or chemoradiation (n = 66) followed by esophagectomy. Pretreatment and pathologic staging were compared to assess response. Overall survival was recorded. Most patients in the chemotherapy and chemoradiation groups had pretreatment stage III disease (66.7% versus 65.2%; P = 0.44). Median follow-up was 79.3 and 64.9 mo for chemotherapy and chemoradiation cohorts, respectively. Complete response rate was higher in chemoradiation than chemotherapy groups (30.3% versus 13.8%; P < 0.001). Overall survival was similar between complete responders in both groups (median not reached versus 121.1 mo; chemotherapy versus chemoradiation). However, partial responders in the chemotherapy cohort had improved median survival (147.2 mo) versus those in the chemoradiation cohort (83.7 mo, P < 0.03). Within the chemotherapy-only group, partial responders had improved survival compared with nonresponders (P = 0.041); however, there was no difference in survival between partial and complete responders (P = 0.36). In patients undergoing esophagectomy for locally advanced esophageal cancer, neoadjuvant chemotherapy was associated with an equivalent overall survival, when compared with neoadjuvant chemoradiotherapy. Adding neoadjuvant radiation may enhance complete response rates but does not appear to be associated with improved survival. Copyright © 2017 Elsevier Inc. All rights reserved.
Dekutoski, Mark B; Clarke, Michelle J; Rose, Peter; Luzzati, Alessandro; Rhines, Laurence D; Varga, Peter P; Fisher, Charles G; Chou, Dean; Fehlings, Michael G; Reynolds, Jeremy J; Williams, Richard; Quraishi, Nasir A; Germscheid, Niccole M; Sciubba, Daniel M; Gokaslan, Ziya L; Boriani, Stefano
2016-07-01
OBJECTIVE Primary spinal osteosarcomas are rare and aggressive neoplasms. Poor outcomes can occur, as obtaining marginal margins is technically demanding; further Enneking-appropriate en bloc resection can have significant morbidity. The goal of this study is to identify prognostic variables for local recurrence and mortality in surgically treated patients diagnosed with a primary osteosarcoma of the spine. METHODS A multicenter ambispective database of surgically treated patients with primary spine osteosarcomas was developed by AOSpine Knowledge Forum Tumor. Patient demographic, diagnosis, treatment, perioperative morbidity, local recurrence, and cross-sectional survival data were collected. Tumors were classified in 2 cohorts: Enneking appropriate (EA) and Enneking inappropriate (EI), as defined by pathology margin matching Enneking-recommended surgical margins. Prognostic variables were analyzed in reference to local recurrence and survival. RESULTS Between 1987 and 2012, 58 patients (32 female patients) underwent surgical treatment for primary spinal osteosarcoma. Patients were followed for a mean period of 3.5 ± 3.5 years (range 0.5 days to 14.3 years). The median survival for the entire cohort was 6.7 years postoperative. Twenty-four (41%) patients died, and 17 (30%) patients suffered a local recurrence, 10 (59%) of whom died. Twenty-nine (53%) patients underwent EA resection while 26 (47%) patients underwent EI resection with a postoperative median survival of 6.8 and 3.7 years, respectively (p = 0.048). EI patients had a higher rate of local recurrence than EA patients (p = 0.001). Patient age, previous surgery, biopsy type, tumor size, spine level, and chemotherapy timing did not significantly influence recurrence and survival. CONCLUSIONS Osteosarcoma of the spine presents a significant challenge, and most patients die in spite of aggressive surgery. There is a significant decrease in recurrence and an increase in survival with en bloc resection (EA) when compared with intralesional resection (EI). The effect of adjuvant and neoadjuvant chemotherapeutics, as well as method of biopsy, requires further exploration.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shapiro, Lauren Q.; Beal, Kathryn, E-mail: bealk@mskcc.org; Goenka, Anuj
2013-03-01
Purpose: Concurrent bevacizumab with hypofractionated stereotactic radiation therapy (HSRT) is safe and effective for the treatment of recurrent high-grade gliomas (HGG). The objective of this study was to characterize the patterns of failure after this treatment regimen. Methods and Materials: Twenty-four patients with recurrent enhancing HGG were previously treated on an institutional review board-approved protocol of concurrent bevacizumab and reirradiation. Patients received 30 Gy in 5 fractions to the recurrent tumor with HSRT. Brain magnetic resonance imaging (MRI) was performed every 2 cycles, and bevacizumab was continued until clinical or radiographic tumor progression according to the criteria of Macdonald etmore » al. MRI at the time of progression was fused to the HSRT treatment plan, and the location of recurrence was classified on the basis of volume within the 95% isodose line. Outcomes based on patient characteristics, tumor grade, recurrence pattern, and best response to treatment were analyzed by the Kaplan-Meier method. Results: Twenty-two patients experienced either clinical or radiographic progression. Recurrent tumor was enhancing in 15 (71.4%) and nonenhancing in 6 (28.6%) patients. Eleven patients (52.4%) had recurrence within the radiation field, 5 patients (23.8%) had marginal recurrence, and 5 patients had recurrence outside the radiation field. Pattern of enhancement and location of failure did not correlate with overall survival or progression-free survival. Radiographic response was the only variable to significantly correlate with progression-free survival. Conclusions: Despite the promising initial response seen with the addition of HSRT to bevacizumab as salvage treatment for recurrent HGG, approximately half of patients ultimately still experience failure within the radiation field. The rate of local failure with the addition of HSRT seems to be lower than that seen with bevacizumab alone in the salvage setting. Our data underscore the radioresistance of HGG and the need for better salvage treatments.« less
Environmental conditions and prey-switching by a seabird predator impact juvenile salmon survival
Wells, Brian K.; Santora, Jarrod A.; Henderson, Mark J.; Warzybok, Pete; Jahncke, Jaime; Bradley, Russell W.; Huff, David D.; Schroeder, Isaac D.; Nelson, Peter; Field, John C.; Ainley, David G.
2017-01-01
Due to spatio-temporal variability of lower trophic-level productivity along the California Current Ecosystem (CCE), predators must be capable of switching prey or foraging areas in response to changes in environmental conditions and available forage. The Gulf of the Farallones in central California represents a biodiversity hotspot and contains the largest common murre (Uria aalge) colonies along the CCE. During spring, one of the West Coast's most important Chinook salmon (Oncorhynchus tshawytscha) populations out-migrates into the Gulf of the Farallones. We quantify the effect of predation on juvenile Chinook salmon associated with ecosystem-level variability by integrating long-term time series of environmental conditions (upwelling, river discharge), forage species abundance within central CCE, and population size, at-sea distribution, and diet of the common murre. Our results demonstrate common murres typically forage in the vicinity of their offshore breeding sites, but in years in which their primary prey, pelagic young-of-year rockfish (Sebastesspp.), are less available they forage for adult northern anchovies (Engraulis mordax) nearshore. Incidentally, while foraging inshore, common murre consumption of out-migrating juvenile Chinook salmon, which are collocated with northern anchovy, increases and population survival of the salmon is significantly reduced. Results support earlier findings that show timing and strength of upwelling, and the resultant forage fish assemblage, is related to Chinook salmon recruitment variability in the CCE, but we extend those results by demonstrating the significance of top-down impacts associated with these bottom-up dynamics. Our results demonstrate the complexity of ecosystem interactions and impacts between higher trophic-level predators and their prey, complexities necessary to quantify in order to parameterize ecosystem models and evaluate likely outcomes of ecosystem management options.
Environmental conditions and prey-switching by a seabird predator impact juvenile salmon survival
NASA Astrophysics Data System (ADS)
Wells, Brian K.; Santora, Jarrod A.; Henderson, Mark J.; Warzybok, Pete; Jahncke, Jaime; Bradley, Russell W.; Huff, David D.; Schroeder, Isaac D.; Nelson, Peter; Field, John C.; Ainley, David G.
2017-10-01
Due to spatio-temporal variability of lower trophic-level productivity along the California Current Ecosystem (CCE), predators must be capable of switching prey or foraging areas in response to changes in environmental conditions and available forage. The Gulf of the Farallones in central California represents a biodiversity hotspot and contains the largest common murre (Uria aalge) colonies along the CCE. During spring, one of the West Coast's most important Chinook salmon (Oncorhynchus tshawytscha) populations out-migrates into the Gulf of the Farallones. We quantify the effect of predation on juvenile Chinook salmon associated with ecosystem-level variability by integrating long-term time series of environmental conditions (upwelling, river discharge), forage species abundance within central CCE, and population size, at-sea distribution, and diet of the common murre. Our results demonstrate common murres typically forage in the vicinity of their offshore breeding sites, but in years in which their primary prey, pelagic young-of-year rockfish (Sebastes spp.), are less available they forage for adult northern anchovies (Engraulis mordax) nearshore. Incidentally, while foraging inshore, common murre consumption of out-migrating juvenile Chinook salmon, which are collocated with northern anchovy, increases and population survival of the salmon is significantly reduced. Results support earlier findings that show timing and strength of upwelling, and the resultant forage fish assemblage, is related to Chinook salmon recruitment variability in the CCE, but we extend those results by demonstrating the significance of top-down impacts associated with these bottom-up dynamics. Our results demonstrate the complexity of ecosystem interactions and impacts between higher trophic-level predators and their prey, complexities necessary to quantify in order to parameterize ecosystem models and evaluate likely outcomes of ecosystem management options.
Wunderle, Marius; Gass, Paul; Häberle, Lothar; Flesch, Vivien M; Rauh, Claudia; Bani, Mayada R; Hack, Carolin C; Schrauder, Michael G; Jud, Sebastian M; Emons, Julius; Erber, Ramona; Ekici, Arif B; Hoyer, Juliane; Vasileiou, Georgia; Kraus, Cornelia; Reis, Andre; Hartmann, Arndt; Lux, Michael P; Beckmann, Matthias W; Fasching, Peter A; Hein, Alexander
2018-05-03
BRCA1/2 mutations influence the molecular characteristics and the effects of systemic treatment of breast cancer. This study investigates the impact of germline BRCA1/2 mutations on pathological complete response and prognosis in patients receiving neoadjuvant systemic chemotherapy. Breast cancer patients were tested for a BRCA1/2 mutation in clinical routine work and were treated with anthracycline-based or platinum-based neoadjuvant chemotherapy between 1997 and 2015. These patients were identified in the tumor registry of the Breast Center of the University of Erlangen (Germany). Logistic regression and Cox regression analyses were performed to investigate the associations between BRCA1/2 mutation status, pathological complete response, disease-free survival, and overall survival. Among 355 patients, 59 had a mutation in BRCA1 or in BRCA2 (16.6%), 43 in BRCA1 (12.1%), and 16 in BRCA2 (4.5%). Pathological complete response defined as "ypT0; ypN0" was observed in 54.3% of BRCA1/2 mutation carriers, but only in 22.6% of non-carriers. The adjusted odds ratio was 2.48 (95% CI 1.26-4.91) for BRCA1/2 carriers versus non-carriers. Patients who achieved a pathological complete response had better disease-free survival and overall survival rates compared with those who did not achieve a pathological complete response, regardless of BRCA1/2 mutation status. BRCA1/2 mutation status leads to better responses to neoadjuvant chemotherapy in breast cancer. Pathological complete response is the main predictor of disease-free survival and overall survival, independently of BRCA1/2 mutation status.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yoo, Tae; Lee, Woo Jin; Woo, Sang Myung
2011-11-15
Purpose: The use of chemoradiotherapy (CRT) for localized and unresectable pancreatic cancer has been disputed because of high probability of distant metastasis. Thus, we analyzed the effect of clinical parameters on tumor response, early distant metastasis within 3 months (DM{sup 3m}), and overall survival to identify an indicator for selecting patients who would benefit from CRT. Methods and Materials: This study retrospectively analyzed the data from 84 patients with localized and unresectable pancreatic cancer who underwent CRT between August 2002 and October 2009. Sex, age, tumor size, histological differentiation, N classification, pre- and post-treatment carbohydrate antigen (CA) 19-9 level, andmore » CA 19-9 percent decrease were analyzed to identify risk factors associated with tumor response, DM{sup 3m}, and overall survival. Results: For all 84 patients, the median survival time was 12.5 months (range, 2-31.9 months), objective response (complete response or partial response) to CRT was observed in 28 patients (33.3%), and DM{sup 3m} occurred in 24 patients (28.6%). Multivariate analysis showed that pretreatment CA 19-9 level ({<=}400 vs. >400 U/ml) was significantly associated with tumor response (45.1% vs. 15.2%), DM{sup 3m} (19.6% vs. 42.4%), and median overall survival time (15.1 vs. 9.7 months) (p < 0.05 for all three parameters). Conclusion: For patients with localized and unresectable pancreatic cancer, pretreatment CA 19-9 level could be helpful in predicting tumor response, DM{sup 3m}, and overall survival and identifying patients who will benefit from CRT.« less
Complex effect of projected sea temperature and wind change on flatfish dispersal.
Lacroix, Geneviève; Barbut, Léo; Volckaert, Filip A M
2018-01-01
Climate change not only alters ocean physics and chemistry but also affects the biota. Larval dispersal patterns from spawning to nursery grounds and larval survival are driven by hydrodynamic processes and shaped by (a)biotic environmental factors. Therefore, it is important to understand the impacts of increased temperature rise and changes in wind speed and direction on larval drift and survival. We apply a particle-tracking model coupled to a 3D-hydrodynamic model of the English Channel and the North Sea to study the dispersal dynamics of the exploited flatfish (common) sole (Solea solea). We first assess model robustness and interannual variability in larval transport over the period 1995-2011. Then, using a subset of representative years (2003-2011), we investigate the impact of climate change on larval dispersal, connectivity patterns and recruitment at the nursery grounds. The impacts of five scenarios inspired by the 2040 projections of the Intergovernmental Panel on Climate Change are discussed and compared with interannual variability. The results suggest that 33% of the year-to-year recruitment variability is explained at a regional scale and that a 9-year period is sufficient to capture interannual variability in dispersal dynamics. In the scenario involving a temperature increase, early spawning and a wind change, the model predicts that (i) dispersal distance (+70%) and pelagic larval duration (+22%) will increase in response to the reduced temperature (-9%) experienced by early hatched larvae, (ii) larval recruitment at the nursery grounds will increase in some areas (36%) and decrease in others (-58%) and (iii) connectivity will show contrasting changes between areas. At the regional scale, our model predicts considerable changes in larval recruitment (+9%) and connectivity (retention -4% and seeding +37%) due to global change. All of these factors affect the distribution and productivity of sole and therefore the functioning of the demersal ecosystem and fisheries management. © 2017 John Wiley & Sons Ltd.
Archer, D C; Pinchbeck, G L; Proudman, C J
2011-08-01
Epiploic foramen entrapment (EFE) has been associated with reduced post operative survival compared to other types of colic but specific factors associated with reduced long-term survival of these cases have not been evaluated in a large number of horses using survival analysis. To describe post operative survival of EFE cases and to identify factors associated with long-term survival. A prospective, multicentre, international study was conducted using clinical data and long-term follow-up information for 126 horses diagnosed with EFE during exploratory laparotomy at 15 clinics in the UK, Ireland and USA. Descriptive data were generated and survival analysis performed to identify factors associated with reduced post operative survival. For the EFE cohort that recovered following anaesthesia, survival to hospital discharge was 78.5%. Survival to 1 and 2 years post operatively was 50.6 and 34.3%, respectively. The median survival time of EFE cases undergoing surgery was 397 days. Increased packed cell volume (PCV) and increased length of small intestine (SI) resected were significantly associated with increased likelihood of mortality when multivariable analysis of pre- and intraoperative variables were analysed. When all pre-, intra- and post operative variables were analysed separately, only horses that developed post operative ileus (POI) were shown to be at increased likelihood of mortality. Increased PCV, increased length of SI resected and POI are all associated with increased likelihood of mortality of EFE cases. This emphasises the importance of early diagnosis and treatment and the need for improved strategies in the management of POI in order to reduce post operative mortality in these cases. The present study provides evidence-based information to clinicians and owners of horses undergoing surgery for EFE about long-term survival. These results are applicable to university and large private clinics over a wide geographical area. © 2011 EVJ Ltd.
Plastic and evolutionary responses to climate change in fish
Crozier, Lisa G; Hutchings, Jeffrey A
2014-01-01
The physical and ecological ‘fingerprints’ of anthropogenic climate change over the past century are now well documented in many environments and taxa. We reviewed the evidence for phenotypic responses to recent climate change in fish. Changes in the timing of migration and reproduction, age at maturity, age at juvenile migration, growth, survival and fecundity were associated primarily with changes in temperature. Although these traits can evolve rapidly, only two studies attributed phenotypic changes formally to evolutionary mechanisms. The correlation-based methods most frequently employed point largely to ‘fine-grained’ population responses to environmental variability (i.e. rapid phenotypic changes relative to generation time), consistent with plastic mechanisms. Ultimately, many species will likely adapt to long-term warming trends overlaid on natural climate oscillations. Considering the strong plasticity in all traits studied, we recommend development and expanded use of methods capable of detecting evolutionary change, such as the long term study of selection coefficients and temporal shifts in reaction norms, and increased attention to forecasting adaptive change in response to the synergistic interactions of the multiple selection pressures likely to be associated with climate change. PMID:24454549
What Is a Mild Winter? Regional Differences in Within-Species Responses to Climate Change.
Vetter, Sebastian G; Ruf, Thomas; Bieber, Claudia; Arnold, Walter
2015-01-01
Climate change is known to affect ecosystems globally, but our knowledge of its impact on large and widespread mammals, and possibly population-specific responses is still sparse. We investigated large-scale and long-term effects of climate change on local population dynamics using the wild boar (Sus scrofa L.) as a model species. Our results show that population increases across Europe are strongly associated with increasingly mild winters, yet with region-specific threshold temperatures for the onset of exponential growth. Additionally, we found that abundant availability of critical food resources, e.g. beech nuts, can outweigh the negative effects of cold winters on population growth of wild boar. Availability of beech nuts is highly variable and highest in years of beech mast which increased in frequency since 1980, according to our data. We conclude that climate change drives population growth of wild boar directly by relaxing the negative effect of cold winters on survival and reproduction, and indirectly by increasing food availability. However, region-specific responses need to be considered in order to fully understand a species' demographic response to climate change.
Plastic and evolutionary responses to climate change in fish.
Crozier, Lisa G; Hutchings, Jeffrey A
2014-01-01
The physical and ecological 'fingerprints' of anthropogenic climate change over the past century are now well documented in many environments and taxa. We reviewed the evidence for phenotypic responses to recent climate change in fish. Changes in the timing of migration and reproduction, age at maturity, age at juvenile migration, growth, survival and fecundity were associated primarily with changes in temperature. Although these traits can evolve rapidly, only two studies attributed phenotypic changes formally to evolutionary mechanisms. The correlation-based methods most frequently employed point largely to 'fine-grained' population responses to environmental variability (i.e. rapid phenotypic changes relative to generation time), consistent with plastic mechanisms. Ultimately, many species will likely adapt to long-term warming trends overlaid on natural climate oscillations. Considering the strong plasticity in all traits studied, we recommend development and expanded use of methods capable of detecting evolutionary change, such as the long term study of selection coefficients and temporal shifts in reaction norms, and increased attention to forecasting adaptive change in response to the synergistic interactions of the multiple selection pressures likely to be associated with climate change.
Variability in Migration Routes Influences Early Marine Survival of Juvenile Salmon Smolts
Furey, Nathan B.; Vincent, Stephen P.; Hinch, Scott G.; Welch, David W.
2015-01-01
Variability in animal migratory behavior is expected to influence fitness, but few empirical examples demonstrating this relationship exist. The initial marine phase in the migration of juvenile salmon smolts has been identified as a potentially critical life history stage to overall population productivity, yet how fine-scale migration routes may influence survival are unknown. Large-scale acoustic telemetry studies have estimated survival rates of outmigrant Pacific salmon smolts through the Strait of Georgia (SOG) along the British Columbian coastline to the Pacific Ocean, but these data have not been used to identify and characterize fine-scale movements. Data collected on over 850 sockeye salmon (Oncorhynchus nerka) and steelhead (Oncorhynchus mykiss) smolts detected at an array in the Strait of Georgia in 2004–2008 and 2010–2013 were analyzed to characterize migration routes and link movements to subsequent survival at an array 250 km further along the marine migration pathway. Both species exhibited disproportionate use of the most eastern route in the Strait of Georgia (Malaspina Strait). While many smolts moved across the northern Strait of Georgia acoustic array with no indication of long-term milling or large-scale east-to-west movements, large proportions (20–40% of sockeye and 30–50% of steelhead) exhibited a different behavior, apparently moving in a westward or counterclockwise pattern. Variability in migratory behavior for both species was linked to subsequent survival through the Strait of Georgia. Survival for both species was influenced by initial east-to-west location, and sockeye were further influenced by migration timing and duration of time spent near the northern Strait of Georgia array. Westward movements result in a net transport of smolts from Malaspina Strait to the Strait of Georgia, particularly for steelhead. Counterclockwise movements may be due to the currents in this area during the time of outmigration, and the higher proportion of steelhead smolts exhibiting this counterclockwise behavior may reflect a greater exposure to wind-altered currents for the more surface-oriented steelhead. Our results provide an empirical example of how movements can affect migration survival, for which examples remain rare in movement ecology, confirming that variability in movements themselves are an important part of the migratory process. PMID:26451837
Zimmitti, Giuseppe; Shindoh, Junichi; Mise, Yoshihiro; Kopetz, Scott; Loyer, Evelyne M; Andreou, Andreas; Cooper, Amanda B; Kaur, Harmeet; Aloia, Thomas A; Maru, Dipen M; Vauthey, Jean-Nicolas
2015-03-01
RAS mutations have been reported to be a potential prognostic factor in patients with colorectal liver metastases (CLM). However, the impact of RAS mutations on response to chemotherapy remains unclear. The purpose of this study was to investigate the correlation between RAS mutations and response to preoperative chemotherapy and their impact on survival in patients undergoing curative resection of CLM. RAS mutational status was assessed and its relation to morphologic response and pathologic response was investigated in 184 patients meeting inclusion criteria. Predictors of survival were assessed. The prognostic impact of RAS mutational status was then analyzed using two different multivariate models, including either radiologic morphologic response (model 1) or pathologic response (model 2). Optimal morphologic response and major pathologic response were more common in patients with wild-type RAS (32.9 and 58.9%, respectively) than in patients with RAS mutations (10.5 and 36.8%; P = 0.006 and 0.015, respectively). Multivariate analysis confirmed that wild-type RAS was a strong predictor of optimal morphologic response [odds ratio (OR), 4.38; 95% CI 1.45-13.15] and major pathologic response (OR, 2.61; 95% CI 1.17-5.80). RAS mutations were independently correlated with both overall survival and recurrence free-survival (hazard ratios, 3.57 and 2.30, respectively, in model 1, and 3.19 and 2.09, respectively, in model 2). Subanalysis revealed that RAS mutational status clearly stratified survival in patients with inadequate response to preoperative chemotherapy. RAS mutational status can be used to complement the current prognostic indicators for patients undergoing curative resection of CLM after preoperative modern chemotherapy.
Konishi, Hirotaka; Fujiwara, Hitoshi; Shiozaki, Atsushi; Hiramoto, Hidekazu; Kosuga, Toshiyuki; Komatsu, Shuhei; Ichikawa, Daisuke; Okamoto, Kazuma; Otsuji, Eigo
2016-02-01
Neo-adjuvant chemotherapy (NAC) followed by radical esophagectomy has been shown to prolong survival in patients with locally advanced esophageal squamous cell carcinoma (ESCC). However, neutropenia, one of the major adverse events due to NAC, influences the therapeutic course. The aim of this study is to clarify the relationship between neutropenia and therapeutic response in ESCC with NAC. A total of 117 patients with clinical stage II/III ESCC who had undergone NAC followed by radical esophagectomy were retrospectively analyzed in terms of the relationship between neutropenia and clinicopathological features or outcomes. Neutropenia was the major adverse event observed in 56 % (66/117) and grade 3/4 neutropenia occurred in 29 % of patients. Grade 3/4 neutropenia correlated with a high histological response (Grade 1b-3) (p < 0.01). Correlative analysis identified grade 3/4 neutropenia and poor differentiation as independent predictors of a high histological response (odds ratio 5.13 and 3.25, p < 0.01 and p = 0.01, respectively). Survival analysis showed that patients with a high histological response had significantly longer survival than those with a low histological response (Grade 0-1a) (p = 0.03), whereas no significant differences were found for survival according to the grade of neutropenia (p = 0.45). In a subgroup analysis according to histological response, grade 3/4 neutropenia correlated with worse survival in patients with a low histological response (p = 0.05). Severe neutropenia due to NAC correlates with a high histological response in ESCC. However, severe neutropenia may also result in a worse prognosis for patients with a low histological response.
Blood pressure response to patterns of weather fluctuations and effect on mortality.
Aubinière-Robb, Louise; Jeemon, Panniyammakal; Hastie, Claire E; Patel, Rajan K; McCallum, Linsay; Morrison, David; Walters, Matthew; Dawson, Jesse; Sloan, William; Muir, Scott; Dominiczak, Anna F; McInnes, Gordon T; Padmanabhan, Sandosh
2013-07-01
Very few studies have looked at longitudinal intraindividual blood pressure responses to weather conditions. There are no data to suggest that specific response to changes in weather will have an impact on survival. We analyzed >169 000 clinic visits of 16 010 Glasgow Blood Pressure Clinic patients with hypertension. Each clinic visit was mapped to the mean West of Scotland monthly weather (temperature, sunshine, rainfall) data. Percentage change in blood pressure was calculated between pairs of consecutive clinic visits, where the weather alternated between 2 extreme quartiles (Q(1)-Q(4) or Q(4)-Q(1)) or remained in the same quartile (Q(n)-Q(n)) of each weather parameter. Subjects were also categorized into 2 groups depending on whether their blood pressure response in Q(1)-Q(4) or Q(4)-Q(1) were concordant or discordant to Q(n)-Q(n). Generalized estimating equations and Cox proportional hazards model were used to model the effect on longitudinal blood pressure and mortality, respectively. Q(n)-Q(n) showed a mean 2% drop in blood pressure consistently, whereas Q(4)-Q(1) showed a mean 2.1% and 1.6% rise in systolic and diastolic blood pressure, respectively. However, Q(1)-Q(4) did not show significant changes in blood pressure. Temperature-sensitive subjects had significantly higher mortality (1.35 [95% confidence interval, 1.06-1.71]; P=0.01) and higher follow-up systolic blood pressure (1.85 [95% confidence interval, 0.24-3.46]; P=0.02) compared with temperature-nonsensitive subjects. Blood pressure response to temperature may be one of the underlying mechanisms that determine long-term blood pressure variability. Knowing a patient's blood pressure response to weather can help reduce unnecessary antihypertensive treatment modification, which may in turn increase blood pressure variability and, thus, risk.
Soares, Paulo C; Abdelhay, Eliana S; Thuler, Luiz Claudio S; Soares, Bruno Moreira; Demachki, Samia; Ferro, Gessica Valéria Rocha; Assumpção, Paulo P; Lamarão, Leticia Martins; Ribeiro Pinto, Luis Felipe; Burbano, Rommel Mario Rodríguez
2018-02-21
Anal residual tumors are consensually identified within six months of chemoradiotherapy and represent a persistent lesion that may have prognostic value for overall survival. The aim of this study was to evaluate the association of HPV and HIV status, p16 expression level and TP53 mutations with the absence of residual tumors (local response) in Squamous Cell Carcinoma (SCC) of the anal canal after chemoradiotherapy. We performed a study on 78 patients with SCC of the anal canal who submitted to chemoradiotherapy and were followed for a six-month period to identify the absence or presence of residual tumors. HPV DNA was identified by polymerase chain reaction and direct sequencing, HIV RNA was detected by TaqMan amplification, p16 expression was detected by western blotting, and the mutational analysis of TP53 was performed by direct sequencing; additionally, samples carrying mutations underwent fluorescent in sit hybridization. The evaluation of the tumor response to treatment was conducted six months after the conclusion of chemoradiotherapy. The following classifications were used to evaluate the outcomes: a) no response (presence of residual tumor) and b) complete response (absence of residual tumor). The significant variables associated with the absence of residual tumors were HPV positive, p16 overexpressed, wild-type TP53, female gender, and stages I and II. Only the presence of HPV was independently correlated with the clinical response; this variable increased the chances of a response within six months by 31-fold. The presence of HPV in tumor cells was correlated with the absence of a residual tumor. This correlation is valuable and can direct future therapeutic approaches in the anal canal.
Octogenarian liver grafts: Is their use for transplant currently justified?
Jiménez-Romero, Carlos; Cambra, Felix; Caso, Oscar; Manrique, Alejandro; Calvo, Jorge; Marcacuzco, Alejandro; Rioja, Paula; Lora, David; Justo, Iago
2017-05-07
To analyse the impact of octogenarian donors in liver transplantation. We present a retrospective single-center study, performed between November 1996 and March 2015, that comprises a sample of 153 liver transplants. Recipients were divided into two groups according to liver donor age: recipients of donors ≤ 65 years (group A; n = 102), and recipients of donors ≥ 80 years (group B; n = 51). A comparative analysis between the groups was performed. Quantitative variables were expressed as mean values and SD, and qualitative variables as percentages. Differences in properties between qualitative variables were assessed by χ 2 test. Comparison of quantitative variables was made by t -test. Graft and patient survivals were estimated using the Kaplan-Meier method. One, 3 and 5-year overall patient survival was 87.3%, 84% and 75.2%, respectively, in recipients of younger grafts vs 88.2%, 84.1% and 66.4%, respectively, in recipients of octogenarian grafts ( P = 0.748). One, 3 and 5-year overall graft survival was 84.3%, 83.1% and 74.2%, respectively, in recipients of younger grafts vs 84.3%, 79.4% and 64.2%, respectively, in recipients of octogenarian grafts ( P = 0.524). After excluding the patients with hepatitis C virus cirrhosis (16 in group A and 10 in group B), the 1, 3 and 5-year patient ( P = 0.657) and graft ( P = 0.419) survivals were practically the same in both groups. Multivariate Cox regression analysis demonstrated that overall patient survival was adversely affected by cerebrovascular donor death, hepatocarcinoma, and recipient preoperative bilirubin, and overall graft survival was adversely influenced by cerebrovascular donor death, and recipient preoperative bilirubin. The standard criteria for utilization of octogenarian liver grafts are: normal gross appearance and consistency, normal or almost normal liver tests, hemodynamic stability with use of < 10 μg/kg per minute of vasopressors before procurement, intensive care unit stay < 3 d, CIT < 9 h, absence of atherosclerosis in the hepatic and gastroduodenal arteries, and no relevant histological alterations in the pre-transplant biopsy, such as fibrosis, hepatitis, cholestasis or macrosteatosis > 30%.
Octogenarian liver grafts: Is their use for transplant currently justified?
Jiménez-Romero, Carlos; Cambra, Felix; Caso, Oscar; Manrique, Alejandro; Calvo, Jorge; Marcacuzco, Alejandro; Rioja, Paula; Lora, David; Justo, Iago
2017-01-01
AIM To analyse the impact of octogenarian donors in liver transplantation. METHODS We present a retrospective single-center study, performed between November 1996 and March 2015, that comprises a sample of 153 liver transplants. Recipients were divided into two groups according to liver donor age: recipients of donors ≤ 65 years (group A; n = 102), and recipients of donors ≥ 80 years (group B; n = 51). A comparative analysis between the groups was performed. Quantitative variables were expressed as mean values and SD, and qualitative variables as percentages. Differences in properties between qualitative variables were assessed by χ2 test. Comparison of quantitative variables was made by t-test. Graft and patient survivals were estimated using the Kaplan-Meier method. RESULTS One, 3 and 5-year overall patient survival was 87.3%, 84% and 75.2%, respectively, in recipients of younger grafts vs 88.2%, 84.1% and 66.4%, respectively, in recipients of octogenarian grafts (P = 0.748). One, 3 and 5-year overall graft survival was 84.3%, 83.1% and 74.2%, respectively, in recipients of younger grafts vs 84.3%, 79.4% and 64.2%, respectively, in recipients of octogenarian grafts (P = 0.524). After excluding the patients with hepatitis C virus cirrhosis (16 in group A and 10 in group B), the 1, 3 and 5-year patient (P = 0.657) and graft (P = 0.419) survivals were practically the same in both groups. Multivariate Cox regression analysis demonstrated that overall patient survival was adversely affected by cerebrovascular donor death, hepatocarcinoma, and recipient preoperative bilirubin, and overall graft survival was adversely influenced by cerebrovascular donor death, and recipient preoperative bilirubin. CONCLUSION The standard criteria for utilization of octogenarian liver grafts are: normal gross appearance and consistency, normal or almost normal liver tests, hemodynamic stability with use of < 10 μg/kg per minute of vasopressors before procurement, intensive care unit stay < 3 d, CIT < 9 h, absence of atherosclerosis in the hepatic and gastroduodenal arteries, and no relevant histological alterations in the pre-transplant biopsy, such as fibrosis, hepatitis, cholestasis or macrosteatosis > 30%. PMID:28533667
The Role of High Dose Interleukin-2 in the Era of Targeted Therapy.
Gills, Jessie; Parker, William P; Pate, Scott; Niu, Sida; Van Veldhuizen, Peter; Mirza, Moben; Holzbeierlein, Jeffery M; Lee, Eugene K
2017-09-01
We assessed survival outcomes following high dose interleukin-2 in a contemporary cohort of patients during the era of targeted agents. We retrospectively reviewed the records of patients with metastatic renal cell carcinoma treated with high dose interleukin-2 between July 2007 and September 2014. Clinicopathological data were abstracted and patient response to therapy was based on RECIST (Response Evaluation Criteria In Solid Tumors), version 1.1 criteria. The Kaplan-Meier method was used to estimate progression-free and overall survival in the entire cohort, the response to high dose interleukin-2 in regard to previous targeted agent therapy and the response to the targeted agent in relation to the response to high dose interleukin-2. We identified 92 patients, of whom 87 had documentation of a response to high dose interleukin-2. Median overall survival was 34.4 months from the initiation of high dose interleukin-2 therapy in the entire cohort. Patients who received targeted therapy before high dose interleukin-2 had overall survival (median 34.4 and 30.0 months, p = 0.88) and progression-free survival (median 1.5 and 1.7 months, p = 0.8) similar to those in patients who received no prior therapy, respectively. Additionally, patients with a complete or partial response to high dose interleukin-2 had similar outcomes for subsequent targeted agents compared to patients whose best response was stable or progressive disease (median overall survival 30.1 vs 25.4 months, p = 0.4). Our data demonstrate that patient responses to high dose interleukin-2 and to targeted agents before and after receiving high dose interleukin-2 are independent. As such, carefully selected patients should be offered high dose interleukin-2 for the possibility of a complete and durable response without the fear of limiting the treatment benefit of targeted agents. Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Zanaga, L.P.; Vigani, A.G.; Angerami, R.N.; Giorgetti, A.; Escanhoela, C.A.F.; Ataíde, E.C.; Boin, I.F.S.F.; Stucchi, R.S.B.
2017-01-01
Recurrent hepatitis C after orthotopic liver transplantation (OLT) is universal and can lead to graft failure and, consequently, reduced survival. Hepatitis C treatment can be used to prevent these detrimental outcomes. The aim of this study was to describe rates of hepatitis C recurrence and sustained virological response (SVR) to interferon-based treatment after OLT and its relationship to survival and progression of liver disease through retrospective analysis of medical records of 127 patients who underwent OLT due to cirrhosis or hepatocellular carcinoma secondary to chronic hepatitis C between January 2002 and December 2013. Fifty-six patients were diagnosed with recurrent disease, 42 started interferon-based therapy and 37 completed treatment. Demographic, treatment- and outcome-related variables were compared between SVR and non-responders (non-SVR). There was an overall 54.1% SVR rate with interferon-based therapies. SVR was associated with longer follow-up after treatment (median 66.5 vs 37 months for non-SVR, P=0.03) and after OLT (median 105 vs 72 months, P=0.074), and lower rates of disease progression (15 vs 64.7%, P=0.0028) and death (5 vs 35.3%, P=0.033). Regardless of the result of therapy (SVR or non-SVR), there was a significant difference between treated and untreated patients regarding the occurrence of death (P<0.001) and months of survival (P<0.001). Even with suboptimal interferon-based therapies (compared to the new direct-acting antivirals) there is a 54.1% SVR rate to treatment. SVR is associated with improved survival and reduced risks of clinical decompensation, loss of the liver graft and death. PMID:28076451
Fulkerson, Daniel H; White, Ian K; Rees, Jacqueline M; Baumanis, Maraya M; Smith, Jodi L; Ackerman, Laurie L; Boaz, Joel C; Luerssen, Thomas G
2015-10-01
Patients with traumatic brain injury (TBI) with low presenting Glasgow Coma Scale (GCS) scores have very high morbidity and mortality rates. Neurosurgeons may be faced with difficult decisions in managing the most severely injured (GCS scores of 3 or 4) patients. The situation may be considered hopeless, with little chance of a functional recovery. Long-term data are limited regarding the clinical outcome of children with severe head injury. The authors evaluate predictor variables and the clinical outcomes at discharge, 1 year, and long term (median 10.5 years) in a cohort of children with TBI presenting with postresuscitation GCS scores of 3 and 4. A review of a prospectively collected trauma database was performed. Patients treated at Riley Hospital for Children (Indianapolis, Indiana) from 1988 to 2004 were reviewed. All children with initial GCS (modified for pediatric patients) scores of 3 or 4 were identified. Patients with a GCS score of 3 were compared with those with a GCS score of 4. The outcomes of all patients at the time of death or discharge and at 1-year and long-term follow-up were measured with a modified Glasgow Outcome Scale (GOS) that included a "normal" outcome. Long-term outcomes were evaluated by contacting surviving patients. Statistical "classification trees" were formed for survival and outcome, based on predictor variables. Sixty-seven patients with a GCS score of 3 or 4 were identified in a database of 1636 patients (4.1%). Three of the presenting factors differed between the GCS 3 patients (n = 44) and the GCS 4 patients (n = 23): presence of hypoxia, single seizure, and open basilar cisterns on CT scan. The clinical outcomes were statistically similar between the 2 groups. In total, 48 (71.6%) of 67 patients died, remained vegetative, or were severely disabled by 1 year. Eight patients (11.9%) were normal at 1 year. Ten of the 22 patients with long-term follow-up were either normal or had a GOS score of 5. Multiple clinical, historical, and radiological factors were analyzed for correlation with survival and clinical outcome. Classification trees were formed to stratify predictive factors. The pupillary response was the factor most predictive of both survival and outcome. Other factors that either positively or negatively correlated with survival included hypothermia, mechanism of injury (abuse), hypotension, major concurrent symptoms, and midline shift on CT scan. Other factors that either positively or negatively predicted long-term outcome included hypothermia, mechanism of injury, and the assessment of the fontanelle. In this cohort of 67 TBI patients with a presenting GCS score of 3 or 4, 56.6% died within 1 year. However, approximately 15% of patients had a good outcome at 10 or more years. Factors that correlated with survival and outcome included the pupillary response, hypothermia, and mechanism. The authors discuss factors that may help surgeons make critical decisions regarding their most serious pediatric trauma patients.
Chandrakesan, Parthasarathy; May, Randal; Weygant, Nathaniel; Qu, Dongfeng; Berry, William L; Sureban, Sripathi M; Ali, Naushad; Rao, Chinthalapally; Huycke, Mark; Bronze, Michael S; Houchen, Courtney W
2016-11-23
Crypt epithelial survival and regeneration after injury require highly coordinated complex interplay between resident stem cells and diverse cell types. The function of Dclk1 expressing tuft cells regulating intestinal epithelial DNA damage response for cell survival/self-renewal after radiation-induced injury is unclear. Intestinal epithelial cells (IECs) were isolated and purified and utilized for experimental analysis. We found that small intestinal crypts of Villin Cre ;Dclk1 f/f mice were hypoplastic and more apoptotic 24 h post-total body irradiation, a time when stem cell survival is p53-independent. Injury-induced ATM mediated DNA damage response, pro-survival genes, stem cell markers, and self-renewal ability for survival and restitution were reduced in the isolated intestinal epithelial cells. An even greater reduction in these signaling pathways was observed 3.5 days post-TBI, when peak crypt regeneration occurs. We found that interaction with Dclk1 is critical for ATM and COX2 activation in response to injury. We determined that Dclk1 expressing tuft cells regulate the whole intestinal epithelial cells following injury through paracrine mechanism. These findings suggest that intestinal tuft cells play an important role in regulating the ATM mediated DNA damage response, for epithelial cell survival/self-renewal via a Dclk1 dependent mechanism, and these processes are indispensable for restitution and function after severe radiation-induced injury.
Public goods games in populations with fluctuating size.
McAvoy, Alex; Fraiman, Nicolas; Hauert, Christoph; Wakeley, John; Nowak, Martin A
2018-05-01
Many mathematical frameworks of evolutionary game dynamics assume that the total population size is constant and that selection affects only the relative frequency of strategies. Here, we consider evolutionary game dynamics in an extended Wright-Fisher process with variable population size. In such a scenario, it is possible that the entire population becomes extinct. Survival of the population may depend on which strategy prevails in the game dynamics. Studying cooperative dilemmas, it is a natural feature of such a model that cooperators enable survival, while defectors drive extinction. Although defectors are favored for any mixed population, random drift could lead to their elimination and the resulting pure-cooperator population could survive. On the other hand, if the defectors remain, then the population will quickly go extinct because the frequency of cooperators steadily declines and defectors alone cannot survive. In a mutation-selection model, we find that (i) a steady supply of cooperators can enable long-term population survival, provided selection is sufficiently strong, and (ii) selection can increase the abundance of cooperators but reduce their relative frequency. Thus, evolutionary game dynamics in populations with variable size generate a multifaceted notion of what constitutes a trait's long-term success. Copyright © 2018 Elsevier Inc. All rights reserved.
Isik, Arda; Peker, Kemal; Firat, Deniz; Yilmaz, Bahri; Sayar, Ilyas; Idiz, Oguz; Cakir, Coskun; Demiryilmaz, Ismail; Yilmaz, Ismayil
2014-01-01
Background The aim of this study was to evaluate the prognostic importance of the metastatic lymph node ratio for stage III colon cancer patients and to find a cut-off value at which the overall survival and disease-free survival change. Material/Methods Patients with pathological stage III colon cancer were retrospectively evaluated for: age; preoperative values of Crp, Cea, Ca 19-9, and Afp; pathologic situation of vascular, perineural, lymphatic, and serosal involvement; and metastatic lymph node ratio values were calculated. Results The study included 58 stage III colon cancer patients: 20 (34.5%) females and 38 (65.5%) males were involved in the study. Multivariate analysis was applied to the following variables to evaluate significance for overall survival and disease-free survival: age, Crp, Cea, perineural invasion, and metastatic lymph node ratio. The metastatic lymph node ratio (<0.25 or ≥0.25) is the only independent variable significant for overall and disease-free survival. Conclusions Metastatic lymph node ratio is an ideal prognostic marker for stage III colon cancer patients, and 0.25 is the cut-off value for prognosis. PMID:25087904
Surviving Sepsis: Taming a Deadly Immune Response
... Issues Subscribe August 2014 Print this issue Surviving Sepsis Taming a Deadly Immune Response En español Send ... Mouth? Looking at Lupus Wise Choices Signs of Sepsis Sepsis can be hard to spot, because its ...
Miller, David A.; Grand, J.B.; Fondell, T.F.; Anthony, M.
2006-01-01
1. Predation plays an integral role in many community interactions, with the number of predators and the rate at which they consume prey (i.e. their functional response) determining interaction strengths. Owing to the difficulty of directly observing predation events, attempts to determine the functional response of predators in natural systems are limited. Determining the forms that predator functional responses take in complex systems is important in advancing understanding of community interactions. 2. Prey survival has a direct relationship to the functional response of their predators. We employed this relationship to estimate the functional response for bald eagle Haliaeetus leucocepalus predation of Canada goose Branta canadensis nests. We compared models that incorporated eagle abundance, nest abundance and alternative prey presence to determine the form of the functional response that best predicted intra-annual variation in survival of goose nests. 3. Eagle abundance, nest abundance and the availability of alternative prey were all related to predation rates of goose nests by eagles. There was a sigmoidal relationship between predation rate and prey abundance and prey switching occurred when alternative prey was present. In addition, predation by individual eagles increased as eagle abundance increased. 4. A complex set of interactions among the three species examined in this study determined survival rates of goose nests. Results show that eagle predation had both prey- and predator-dependent components with no support for ratio dependence. In addition, indirect interactions resulting from the availability of alternative prey had an important role in mediating the rate at which eagles depredated nests. As a result, much of the within-season variation in nest survival was due to changing availability of alternative prey consumed by eagles. 5. Empirical relationships drawn from ecological theory can be directly integrated into the estimation process to determine the mechanisms responsible for variation in observed survival rates. The relationship between predator functional response and prey survival offers a flexible and robust method to advance our understanding of predator-prey interactions in many complex natural systems where prey populations are marked and regularly visited. ?? 2006 British Ecological Society.
Predictive factors of response to mTOR inhibitors in neuroendocrine tumours.
Zatelli, Maria Chiara; Fanciulli, Giuseppe; Malandrino, Pasqualino; Ramundo, Valeria; Faggiano, Antongiulio; Colao, Annamaria
2016-03-01
Medical treatment of neuroendocrine tumours (NETs) has drawn a lot of attention due to the recent demonstration of efficacy of several drugs on progression-free survival, including somatostatin analogs, small tyrosine kinase inhibitors and mTOR inhibitors (or rapalogs). The latter are approved as therapeutic agents in advanced pancreatic NETs and have been demonstrated to be effective in different types of NETs, with variable efficacy due to the development of resistance to treatment. Early detection of patients that may benefit from rapalogs treatment is of paramount importance in order to select the better treatment and avoid ineffective and expensive treatments. Predictive markers for therapeutic response are under intensive investigation, aiming at a tailored patient management and more appropriate resource utilization. This review summarizes the available data on the tissue, circulating and imaging markers that are potentially predictive of rapalog efficacy in NETs. © 2016 Society for Endocrinology.
Rojas-Zamora, Oscar; Insuasty-Torres, Jennyfer; de Cardenas, Camilo los Angeles; Ríos, Orlando Vargas
2013-03-01
Ecological restoration of the Andean paramos faces several ecological barriers mainly at the phase of dispersal and establishment of native species. With the aim to contribute to the enrichment of degraded areas, different strategies have to be developed to overcome those barriers. In this work we studied the response of individuals of Espeletia grandiflora (Asteraceae) to the relocation as a strategy for ecological restoration programs. We also evaluated the effect of size of relocated individuals on their survival and development. The work was carried out in an experimental plot at 3 424m altitude in the sector "Lagunas de Siecha" of Chingaza National Park, Colombia. We relocated 200 plants that belonged to three different size classes: 5, 10 and 15cm of initial height. The following variables were registered: survival, plant height, number of living leaves and stem diameter of each individual. We also evaluated the differences between individuals in survival and development. In terms of survival the most efficient size classes corresponded to 15cm high; the survival was 85% after two years. The relative growth rates for height and stem diameter decreases with the increase in size, but the absolute increase in height did not show significant differences between the three sizes tested. Since the stem diameter was found the strongest survival predictor after two years of relocation activities, we suggest its use as a criterion for selection of relocation individuals. The relocation of individuals of E. grandiflora had a positive side effect, carrying other species that may contribute to the enrichment and restoration of degraded areas. Among these, we found species of the genus Hypericum, as well as Arcytophyllum nitidum and Calamagrostis effusa, which should be evaluated in terms of survival and development for the subsequent implementation of the relocation strategy. In this study we verified the successful relocation of individuals of E. grandiflora as a strategy for enrichment of paramos, and provided values of survival and growth, which should be useful for planning and predicting with greater certainty the success of restoration programs in the paramo.
Ellingson, Benjamin M.; Lai, Albert; Nguyen, Huytram N.; Nghiemphu, Phioanh L.; Pope, Whitney B.; Cloughesy, Timothy F.
2015-01-01
Purpose Evaluation of nonenhancing tumor (NET) burden is an important, yet challenging part of brain tumor response assessment. The current study focuses on using dual echo turbo spin echo MRI as a means of quickly estimating tissue T2, which can be used to objectively define NET burden. Experimental Design A series of experiments were performed to establish the use of T2 maps for defining NET burden. First, variation in T2 was determined using ACR water phantoms in 16 scanners evaluated over 3 years. Next, sensitivity and specificity of T2 maps for delineating NET from other tissues was examined. Then, T2-defined NET was used to predict survival in separate subsets of glioblastoma patients treated with radiation therapy, concurrent radiation and chemotherapy, or bevacizumab at recurrence. Results Variability in T2 in the ACR phantom was 3-5%. In training data, ROC analysis suggested that 125ms < T2 < 250ms could delineate NET with a sensitivity >90% and specificity >65%. Using this criterion, NET burden after completion of radiation therapy alone, or concurrent radiation therapy and chemotherapy, was shown to be predictive of survival (Cox, P<0.05), and the change in NET volume before and after bevacizumab therapy in recurrent glioblastoma was also a predictive of survival (P<0.05). Conclusions T2 maps using dual echo data are feasible, stable, and can be used to objectively define NET burden for use in brain tumor characterization, prognosis, and response assessment. The use of effective T2 maps for defining NET burden should be validated in a randomized clinical trial. PMID:25901082
Rodríguez, Marta; Cantos, Blanca; Sabín, Pilar; Quero, Cristina; García-Arroyo, Francisco R.; Rueda, Antonio; Maximiano, Constanza; Rodríguez-Abreu, Delvys; Sánchez, Antonio; Silva, Javier
2017-01-01
Purpose To determine the feasibility of mRNAs (C-MYC, BCL-XL, BCL-6, NF-κβ, PTEN and AKT) in exosomes of plasma as a liquid biopsy method for monitoring and prognostic evolution in B-cell lymphomas. Patients and Methods Exosomes were isolated from 98 patients with B-cell Lymphoma and 68 healthy controls. mRNAs were analyzed by quantitative PCR. An additional 31 post-treatment samples were also studied. Results In the general and follicular lymphoma series, the presence of AKT mRNA was associated with poor response to rituximab-based treatment. Patients with first relapse or disease progression showed a lower percentage of PTEN and BCL-XL mRNA. The presence of BCL-6 mRNA was associated with a high death rate. The absence of PTEN mRNA in the general series, and presence of C-MYC mRNA in follicular lymphomas, were associated with short progression-free survival. BCL-6 and C-MYC mRNA were independent prognostic variables of overall survival. C-MYC mRNA may provide prognostic information with respect to overall survival. BCL-XL mRNA and increase of BCL-6 mRNA in post-treatment samples could serve as molecular monitoring markers. Conclusions This is the first large study to evaluate the prognostic and predictive values of pretreatment tumor-associated mRNA in exosomes. BCL-6 and C-MYC mRNA positivity in pretreatment samples were predictors of worse PFS compared to patients with mRNA negativity. C-MYC mRNA positivity was also a statistically significant predictor of inability to obtain complete response with first-line therapy. PMID:28881619
Provencio, Mariano; Rodríguez, Marta; Cantos, Blanca; Sabín, Pilar; Quero, Cristina; García-Arroyo, Francisco R; Rueda, Antonio; Maximiano, Constanza; Rodríguez-Abreu, Delvys; Sánchez, Antonio; Silva, Javier; García, Vanesa
2017-08-01
To determine the feasibility of mRNAs ( C-MYC, BCL-XL, BCL-6, NF-κβ, PTEN and AKT ) in exosomes of plasma as a liquid biopsy method for monitoring and prognostic evolution in B-cell lymphomas. Exosomes were isolated from 98 patients with B-cell Lymphoma and 68 healthy controls. mRNAs were analyzed by quantitative PCR. An additional 31 post-treatment samples were also studied. In the general and follicular lymphoma series, the presence of AKT mRNA was associated with poor response to rituximab-based treatment. Patients with first relapse or disease progression showed a lower percentage of PTEN and BCL-XL mRNA. The presence of BCL-6 mRNA was associated with a high death rate. The absence of PTEN mRNA in the general series, and presence of C-MYC mRNA in follicular lymphomas, were associated with short progression-free survival. BCL-6 and C-MYC mRNA were independent prognostic variables of overall survival. C-MYC mRNA may provide prognostic information with respect to overall survival. BCL-XL mRNA and increase of BCL-6 mRNA in post-treatment samples could serve as molecular monitoring markers. This is the first large study to evaluate the prognostic and predictive values of pretreatment tumor-associated mRNA in exosomes. BCL-6 and C-MYC mRNA positivity in pretreatment samples were predictors of worse PFS compared to patients with mRNA negativity. C-MYC mRNA positivity was also a statistically significant predictor of inability to obtain complete response with first-line therapy.
Behavioural fever is a synergic signal amplifying the innate immune response.
Boltaña, Sebastian; Rey, Sonia; Roher, Nerea; Vargas, Reynaldo; Huerta, Mario; Huntingford, Felicity Anne; Goetz, Frederick William; Moore, Janice; Garcia-Valtanen, Pablo; Estepa, Amparo; Mackenzie, S
2013-09-07
Behavioural fever, defined as an acute change in thermal preference driven by pathogen recognition, has been reported in a variety of invertebrates and ectothermic vertebrates. It has been suggested, but so far not confirmed, that such changes in thermal regime favour the immune response and thus promote survival. Here, we show that zebrafish display behavioural fever that acts to promote extensive and highly specific temperature-dependent changes in the brain transcriptome. The observed coupling of the immune response to fever acts at the gene-environment level to promote a robust, highly specific time-dependent anti-viral response that, under viral infection, increases survival. Fish that are not offered a choice of temperatures and that therefore cannot express behavioural fever show decreased survival under viral challenge. This phenomenon provides an underlying explanation for the varied functional responses observed during systemic fever. Given the effects of behavioural fever on survival and the fact that it exists across considerable phylogenetic space, such immunity-environment interactions are likely to be under strong positive selection.
Alza, Carissa M; Donnelly, Maureen A; Whitfield, Steven M
2016-12-01
Amphibian populations are declining globally, and multiple anthropogenic stressors, including contamination by pesticides and shifting climates, are driving these declines. Climate change may increase average temperatures or increase temperature variability, either of which may affect the susceptibility of nontarget organisms to contaminants. Eight-day ecotoxicological assays were conducted with red-eyed treefrog (Agalychnis callidryas) larvae to test for additive and interactive effects of exposure to the fungicide chlorothalonil, average temperature, and temperature variability on tadpole growth and survival. Egg masses were collected from seasonal ponds at La Selva Biological Station in Costa Rica, and tadpoles were exposed to a series of chlorothalonil concentrations across a range of ecologically relevant mean temperatures (23.4-27.3 °C) and daily temperature fluctuations (1.1-9.9 °C). Survival was measured each day, and tadpole growth was measured at the end of each trial. Concentrations of chlorothalonil ≥60 µg/L reduced survival, although survival was not affected by mean temperature or daily temperature range, and there were no synergistic interactions between chlorothalonil and temperature regime on survival. Chlorothalonil suppressed tadpole growth at relatively low concentrations (∼15 µg/L). There were impacts of both average temperature and daily temperature range on tadpole growth, although there were no synergistic interactions between temperature regimes and chlorothalonil. The results should inform efforts to manage ecosystems impacted by multiple large-scale anthropogenic stressors as well as methods for the design of ecologically appropriate toxicology trials. Environ Toxicol Chem 2016;35:2998-3004. © 2016 SETAC. © 2016 SETAC.
The predicted influence of climate change on lesser prairie-chicken reproductive parameters
Grisham, Blake A.; Boal, Clint W.; Haukos, David A.; Davis, D.; Boydston, Kathy K.; Dixon, Charles; Heck, Willard R.
2013-01-01
The Southern High Plains is anticipated to experience significant changes in temperature and precipitation due to climate change. These changes may influence the lesser prairie-chicken (Tympanuchus pallidicinctus) in positive or negative ways. We assessed the potential changes in clutch size, incubation start date, and nest survival for lesser prairie-chickens for the years 2050 and 2080 based on modeled predictions of climate change and reproductive data for lesser prairie-chickens from 2001-2011 on the Southern High Plains of Texas and New Mexico. We developed 9 a priori models to assess the relationship between reproductive parameters and biologically relevant weather conditions. We selected weather variable(s) with the most model support and then obtained future predicted values from climatewizard.org. We conducted 1,000 simulations using each reproductive parameter's linear equation obtained from regression calculations, and the future predicted value for each weather variable to predict future reproductive parameter values for lesser prairie-chickens. There was a high degree of model uncertainty for each reproductive value. Winter temperature had the greatest effect size for all three parameters, suggesting a negative relationship between above-average winter temperature and reproductive output. The above-average winter temperatures are correlated to La Nina events, which negatively affect lesser prairie-chickens through resulting drought conditions. By 2050 and 2080, nest survival was predicted to be below levels considered viable for population persistence; however, our assessment did not consider annual survival of adults, chick survival, or the positive benefit of habitat management and conservation, which may ultimately offset the potentially negative effect of drought on nest survival.
The predicted influence of climate change on lesser prairie-chicken reproductive parameters.
Grisham, Blake A; Boal, Clint W; Haukos, David A; Davis, Dawn M; Boydston, Kathy K; Dixon, Charles; Heck, Willard R
2013-01-01
The Southern High Plains is anticipated to experience significant changes in temperature and precipitation due to climate change. These changes may influence the lesser prairie-chicken (Tympanuchus pallidicinctus) in positive or negative ways. We assessed the potential changes in clutch size, incubation start date, and nest survival for lesser prairie-chickens for the years 2050 and 2080 based on modeled predictions of climate change and reproductive data for lesser prairie-chickens from 2001-2011 on the Southern High Plains of Texas and New Mexico. We developed 9 a priori models to assess the relationship between reproductive parameters and biologically relevant weather conditions. We selected weather variable(s) with the most model support and then obtained future predicted values from climatewizard.org. We conducted 1,000 simulations using each reproductive parameter's linear equation obtained from regression calculations, and the future predicted value for each weather variable to predict future reproductive parameter values for lesser prairie-chickens. There was a high degree of model uncertainty for each reproductive value. Winter temperature had the greatest effect size for all three parameters, suggesting a negative relationship between above-average winter temperature and reproductive output. The above-average winter temperatures are correlated to La Niña events, which negatively affect lesser prairie-chickens through resulting drought conditions. By 2050 and 2080, nest survival was predicted to be below levels considered viable for population persistence; however, our assessment did not consider annual survival of adults, chick survival, or the positive benefit of habitat management and conservation, which may ultimately offset the potentially negative effect of drought on nest survival.
Survivalism and Public Opinion on Criminality: A Cross-National Analysis of Prostitution
ERIC Educational Resources Information Center
Stack, Steven; Adamczyk, Amy; Cao, Liqun
2010-01-01
Explanations of variability in public opinion on crime have drawn disproportionately from the literature on specific symbolic orientations including religious fundamentalism and racial prejudice. In contrast, this article hypothesizes that public opinion is linked to the strength of a general cultural axis of nations: survivalism vs.…
Choi, Seung Hee; Terrell, Jeffrey E; Fowler, Karen E; McLean, Scott A; Ghanem, Tamer; Wolf, Gregory T; Bradford, Carol R; Taylor, Jeremy; Duffy, Sonia A
2016-01-01
The Institute of Medicine (IOM) report, "Unequal Treatment," which defines disparities as racially based, indicates that disparities in cancer diagnosis and treatment are less clear. While a number of studies have acknowledged cancer disparities, they have limitations of retrospective nature, small sample sizes, inability to control for covariates, and measurement errors. The purpose of this study was to examine disparities as predictors of survival among newly diagnosed head and neck cancer patients recruited from 3 hospitals in Michigan, USA, while controlling for a number of covariates (health behaviors, medical comorbidities, and treatment modality). Longitudinal data were collected from newly diagnosed head and neck cancer patients (N = 634). The independent variables were median household income, education, race, age, sex, and marital status. The outcome variables were overall, cancer-specific, and disease-free survival censored at 5 years. Kaplan-Meier curves and univariate and multivariate Cox proportional hazards models were performed to examine demographic disparities in relation to survival. Five-year overall, cancer-specific, and disease-free survival were 65.4% (407/622), 76.4% (487/622), and 67.0% (427/622), respectively. Lower income (HR, 1.5; 95% CI, 1.1-2.0 for overall survival; HR, 1.4; 95% CI, 1.0-1.9 for cancer-specific survival), high school education or less (HR, 1.4; 95% CI, 1.1-1.9 for overall survival; HR, 1.4; 95% CI, 1.1-1.9 for cancer-specific survival), and older age in decades (HR, 1.4; 95% CI, 1.2-1.7 for overall survival; HR, 1.2; 95% CI, 1.1-1.4 for cancer-specific survival) decreased both overall and disease-free survival rates. A high school education or less (HR, 1.4; 95% CI, 1.0-2.1) and advanced age (HR, 1.3; 95% CI, 1.1-1.6) were significant independent predictors of poor cancer-specific survival. Low income, low education, and advanced age predicted poor survival while controlling for a number of covariates (health behaviors, medical comorbidities, and treatment modality). Recommendations from the Institute of Medicine's Report to reduce disparities need to be implemented in treating head and neck cancer patients.
Rise and Shock: Optimal Defibrillator Placement in a High-rise Building.
Chan, Timothy C Y
2017-01-01
Out-of-hospital cardiac arrests (OHCA) in high-rise buildings experience lower survival and longer delays until paramedic arrival. Use of publicly accessible automated external defibrillators (AED) can improve survival, but "vertical" placement has not been studied. We aim to determine whether elevator-based or lobby-based AED placement results in shorter vertical distance travelled ("response distance") to OHCAs in a high-rise building. We developed a model of a single-elevator, n-floor high-rise building. We calculated and compared the average distance from AED to floor of arrest for the two AED locations. We modeled OHCA occurrences using floor-specific Poisson processes, the risk of OHCA on the ground floor (λ 1 ) and the risk on any above-ground floor (λ). The elevator was modeled with an override function enabling direct travel to the target floor. The elevator location upon override was modeled as a discrete uniform random variable. Calculations used the laws of probability. Elevator-based AED placement had shorter average response distance if the number of floors (n) in the building exceeded three quarters of the ratio of ground-floor OHCA risk to above-ground floor risk (λ 1 /λ) plus one half (n ≥ 3λ 1 /4λ + 0.5). Otherwise, a lobby-based AED had shorter average response distance. If OHCA risk on each floor was equal, an elevator-based AED had shorter average response distance. Elevator-based AEDs travel less vertical distance to OHCAs in tall buildings or those with uniform vertical risk, while lobby-based AEDs travel less vertical distance in buildings with substantial lobby, underground, and nearby street-level traffic and OHCA risk.
2012-01-01
Background A sound understanding of malaria transmission patterns in the People’s Republic of China (P.R. China) is crucial for designing effective surveillance-response strategies that can guide the national malaria elimination programme (NMEP). Using an established biology-driven model, it is expected that one may design and refine appropriate surveillance-response strategies for different transmission zones, which, in turn, assist the NMEP in the ongoing implementation period (2010–2020) and, potentially, in the post-elimination stage (2020–2050). Methods Environmental data obtained from 676 locations across P.R. China, such as monthly temperature and yearly relative humidity (YRH), for the period 1961–2000 were prepared. Smoothed surface maps of the number of months suitable for parasite survival derived from monthly mean temperature and YRH were generated. For each decade, the final malaria prediction map was overlaid by two masked maps, one showing the number of months suitable for parasite survival and the other the length of YRH map in excess of 60%. Results Considering multiple environmental factors simultaneously, the environmental variables suitable for malaria transmission were found to have shifted northwards, which was especially pronounced in northern P.R. China. The unstable suitable regions (transmission periods between five and six months) showed increased transmission intensity due to prolonged suitable periods, especially in the central part of the country. Conclusion Adequate and effective surveillance-response strategies for NMEP should be designed to achieve the goal of malaria elimination in P.R. China by 2020, especially in the zones predicted to be the most vulnerable for climate change. PMID:23256579
Biotic context and soil properties modulate native plant responses to enhanced rainfall.
Eskelinen, Anu; Harrison, Susan
2015-11-01
The environmental and biotic context within which plants grow have a great potential to modify responses to climatic changes, yet few studies have addressed both the direct effects of climate and the modulating roles played by variation in the biotic (e.g. competitors) and abiotic (e.g. soils) environment. In a grassland with highly heterogeneous soils and community composition, small seedlings of two native plants, Lasthenia californica and Calycadenia pauciflora, were transplanted into factorially watered and fertilized plots. Measurements were made to test how the effect of climatic variability (mimicked by the watering treatment) on the survival, growth and seed production of these species was modulated by above-ground competition and by edaphic variables. Increased competition outweighed the direct positive impacts of enhanced rainfall on most fitness measures for both species, resulting in no net effect of enhanced rainfall. Both species benefitted from enhanced rainfall when the absence of competitors was accompanied by high soil water retention capacity. Fertilization did not amplify the watering effects; rather, plants benefitted from enhanced rainfall or competitor removal only in ambient nutrient conditions with high soil water retention capacity. The findings show that the direct effects of climatic variability on plant fitness may be reversed or neutralized by competition and, in addition, may be strongly modulated by soil variation. Specifically, coarse soil texture was identified as a factor that may limit plant responsiveness to altered water availability. These results highlight the importance of considering the abiotic as well as biotic context when making future climate change forecasts. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Gittins, John R; D'Angelo, Cecilia; Oswald, Franz; Edwards, Richard J; Wiedenmann, Jörg
2015-01-01
The genomic framework that enables corals to adjust to unfavourable conditions is crucial for coral reef survival in a rapidly changing climate. We have explored the striking intraspecific variability in the expression of coral pigments from the green fluorescent protein (GFP) family to elucidate the genomic basis for the plasticity of stress responses among reef corals. We show that multicopy genes can greatly increase the dynamic range over which corals can modulate transcript levels in response to the light environment. Using the red fluorescent protein amilFP597 in the coral Acropora millepora as a model, we demonstrate that its expression increases with light intensity, but both the minimal and maximal gene transcript levels vary markedly among colour morphs. The pigment concentration in the tissue of different morphs is strongly correlated with the number of gene copies with a particular promoter type. These findings indicate that colour polymorphism in reef corals can be caused by the environmentally regulated expression of multicopy genes. High-level expression of amilFP597 is correlated with reduced photodamage of zooxanthellae under acute light stress, supporting a photoprotective function of this pigment. The cluster of light-regulated pigment genes can enable corals to invest either in expensive high-level pigmentation, offering benefits under light stress, or to rely on low tissue pigment concentrations and use the conserved resources for other purposes, which is preferable in less light-exposed environments. The genomic framework described here allows corals to pursue different strategies to succeed in habitats with highly variable light stress levels. In summary, our results suggest that the intraspecific plasticity of reef corals' stress responses is larger than previously thought. © 2014 The Authors Molecular Ecology Published by John Wiley & Sons Ltd.
Buscardo, Erika; Freitas, Helena; Pereira, João Santos; De Angelis, Paolo
2011-08-01
Natural seedling regeneration and establishment after stand replacing wildfires is influenced by a series of environmental and biological constraints. In this study, we characterized the diversity and structure of the ectomycorrhizal (ECM) fungal community associated with post-fire naturally regenerated maritime pine saplings, and individuate the environmental factors responsible for fungal species distribution. We also identify the main environmental factors responsible for maritime pine regeneration variability and assessed the relation between saplings performance and ECM fungal diversity indices. Fungal species were identified by direct sequencing of internal transcribed spacer regions. Five years after the disturbance event, a total of 30 taxa colonized the pine saplings. The ECM fungal community was dominated by ruderal species of the genus Rhizopogon (present in almost half of the samples). Almost one third of the identified ECM fungal species belonged to the family Thelephoraceae. Typical k-selected species like Amanita pantherina, Boletus aestivalis, Lactarius chrysorrheus, and Russula densifolia were found on pine saplings collected in proximity of unburnt pine trees, in correspondence with low erosion extents. Pine regeneration varied throughout the study areas and was enhanced at higher elevations, in correspondence with moderate slopes, shallower soils, and a reduced cover of ericaceous shrubs and bare ground. These conditions were found in close proximity to patches of pine trees that survived the disturbance event and were previously characterized by a higher pre-fire pine biomass. Even though no correlations were found between saplings performance and ECM fungal diversity indices, common environmental factors (i.e., ericaceous shrub cover, extent of erosion, slope, and soil depth) were responsible for shaping the ECM fungal distribution and for describing most of the explained regeneration variability.
Quality of life scores predict survival among patients with head and neck cancer.
Karvonen-Gutierrez, Carrie A; Ronis, David L; Fowler, Karen E; Terrell, Jeffrey E; Gruber, Stephen B; Duffy, Sonia A
2008-06-01
The purpose of this study was to examine whether quality of life (QOL) scores predict survival among patients with head and neck cancer, controlling for demographic, health behavior, and clinical variables. A self-administered questionnaire was given to 495 patients being treated for head and neck cancer while they were waiting to be seen for a clinic appointment. Data collected from the survey included demographics, health behaviors, and QOL as measured by Short Form-36 (SF-36) physical and mental component scores and the Head and Neck QOL scores. Clinical measures were collected by chart abstraction. Kaplan-Meier plots and univariate and multivariate Cox proportional hazards models were used to determine the association between QOL scores and survival time. After controlling for age, time since diagnosis, marital status, education, tumor site and stage, comorbidities, and smoking, the SF-36 physical component score and three of the four Head and Neck QOL scales (pain, eating, and speech domains) were associated with survival. Controlling for the same variables, the SF-36 mental component score and the emotional domain of the Head and Neck QOL were not associated with survival. QOL instruments may be valuable screening tools to identify patients who are at high risk for poor survival. Those with low QOL scores could be followed more closely, with the potential to identify recurrence earlier and perform salvage treatments, thereby possibly improving survival for this group of patients.
Roué, Tristan; Labbé, Sylvain; Belliardo, Sophie; Plenet, Juliette; Douine, Maylis; Nacher, Mathieu
2016-08-01
The prognosis of patients with breast cancer in French Guiana is worse than in France, with 23 deaths per 100 incident cases versus 17 per 100 in metropolitan France. This study aimed to compare the relative survival of patients with invasive breast cancer (IBC) between women from French Guiana and metropolitan France and to determine risk factors influencing breast cancer survival in French Guiana. Data were collected from the Cancer Registry of French Guiana. We compared the relative survival of women with IBC between French Guiana and metropolitan France. We used the Cox proportional hazard regression to evaluate the effect of prognostic factors on cancer-specific mortality in French Guiana. We included all 269 cases of IBC in women diagnosed in French Guiana between 2003 and 2009. The overall 5-year relative survival rate of patients with IBC was 79% in French Guiana and 86% in metropolitan France. The place of birth (foreign country vs. French territory), the tumor stage at the time of diagnosis, the mode of diagnosis (symptoms vs. screening), the presence of hormone receptors in the tumor, and the histologic type were the variables associated with survival differences. None of the other study variables were significantly associated with prognosis. Access to care for migrants is challenging, which leads to health inequalities. Early detection through prevention programs is crucial to increase IBC survival, notably for foreign-born patients. Copyright © 2016 Elsevier Inc. All rights reserved.
[Surgical treatment of the primary tumor in stage IV breast cancer].
Jiménez Anula, Juan; Sánchez Andújar, Belén; Machuca Chiriboga, Pablo; Navarro Cecilia, Joaquín; Dueñas Rodríguez, Basilio
2015-01-01
The aim of the study was to analyze the impact of loco-regional surgery on survival of patients with stage IV breast cancer. Retrospective study that included patients with breast cancer and synchronous metastases. Patients with ECOG above 2 and high-risk patients were excluded. The following variables were evaluated: age, tumor size, nodal involvement, histological type, histological grade, hormone receptor status, HER2 overexpression, number of affected organs, location of metastases and surgical treatment. The impact of surgery and several clinical and pathologic variables on survival was analyzed by Cox regression model. A total of 69 patients, of whom 36 (52.2%) underwent surgery (study group) were included. After a mean follow-up of 34 months, the median survival of the series was 55 months and no significant differences between the study group and the group of patients without surgery (P=0.187) were found. Two factors associated with worse survival were identified: the number of organs with metastases (HR=1.69, IC 95%: 1.05-2.71) and triple negative breast cancer (HR=3.49, IC 95%: 1.39-8.74). Loco-regional surgery, however, was not associated with survival. Loco-regional surgical treatment was not associated with improved survival inpacientes with stage IV breast cancer. The number of organs with metastases and tumors were triple negative prognostic factors for survival. Copyright © 2014 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.
Yeung, J M C; Kalff, V; Hicks, R J; Drummond, E; Link, E; Taouk, Y; Michael, M; Ngan, S; Lynch, A C; Heriot, A G
2011-05-01
Complete pathological response has proven prognostic benefits in patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy. Sequential 18-FDG PET may be an early surrogate for pathological response to chemoradiotherapy. The aim of this study was to identify whether metabolic response measured by FDG PET following chemoradiotherapy is prognostic for tumor recurrence and survival following neoadjuvant therapy and surgical treatment for primary rectal cancer. Patients with primary rectal cancer treated by long-course neoadjuvant chemoradiotherapy followed by surgery had FDG PET performed before and 4 weeks after treatment, before surgical resection was performed. Retrospective chart review was undertaken for patient demographics, tumor staging, recurrence rates, and survival. : Between 2000 and 2007, 78 patients were identified (53 male, 25 female; median age, 64 y). After chemoradiotherapy, 37 patients (47%) had a complete metabolic response, 26 (33%) had a partial metabolic response, and 14 (18%) had no metabolic response as assessed by FDG PET (1 patient had missing data). However, only 4 patients (5%) had a complete pathological response. The median postoperative follow-up period was 3.1 years during which 14 patients (19%) had a recurrence: 2 local, 9 distant, and 3 with both local and distant. The estimated percentage without recurrence was 77% at 5 years (95% CI 66%-89%). There was an inverse relationship between FDG PET metabolic response and the incidence of recurrence within 3 years (P = .04). Kaplan-Meier analysis of FDG PET metabolic response and overall survival demonstrated a significant difference in survival among patients in the 3 arms: complete, partial, and no metabolic response (P = .04); the patients with complete metabolic response had the best prognosis. Complete or partial metabolic response on PET following neoadjuvant chemoradiotherapy and surgery predicts a lower local recurrence rate and improved survival compared with patients with no metabolic response. Metabolic response may be used to stratify prognosis in patients with rectal cancer.
Parvez, Aatif; Tau, Noam; Hussey, Douglas; Maganti, Manjula; Metser, Ur
2018-05-12
To determine whether metabolic tumor parameters and radiomic features extracted from 18 F-FDG PET/CT (PET) can predict response to therapy and outcome in patients with aggressive B-cell lymphoma. This institutional ethics board-approved retrospective study included 82 patients undergoing PET for aggressive B-cell lymphoma staging. Whole-body metabolic tumor volume (MTV) using various thresholds and tumor radiomic features were assessed on representative tumor sites. The extracted features were correlated with treatment response, disease-free survival (DFS) and overall survival (OS). At the end of therapy, 66 patients (80.5%) had shown complete response to therapy. The parameters correlating with response to therapy were bulky disease > 6 cm at baseline (p = 0.026), absence of a residual mass > 1.5 cm at the end of therapy CT (p = 0.028) and whole-body MTV with best performance using an SUV threshold of 3 and 6 (p = 0.015 and 0.009, respectively). None of the tumor texture features were predictive of first-line therapy response, while a few of them including GLNU correlated with disease-free survival (p = 0.013) and kurtosis correlated with overall survival (p = 0.035). Whole-body MTV correlates with response to therapy in patient with aggressive B-cell lymphoma. Tumor texture features could not predict therapy response, although several features correlated with the presence of a residual mass at the end of therapy CT and others correlated with disease-free and overall survival. These parameters should be prospectively validated in a larger cohort to confirm clinical prognostication.
Andreou, Andreas; Aloia, Thomas A.; Brouquet, Antoine; Dickson, Paxton V.; Zimmitti, Giuseppe; Maru, Dipen M.; Kopetz, Scott; Loyer, Evelyne M.; Curley, Steven A.; Abdalla, Eddie K.; Vauthey, Jean-Nicolas
2013-01-01
Objective To determine the impact of surgical margin status on overall survival (OS) of patients undergoing hepatectomy for colorectal liver metastases (CLM) after modern preoperative chemotherapy. Summary Background Data In the era of effective chemotherapy for CLM, the association between surgical margin status and survival has become controversial. Methods Clinicopathologic data and outcomes for 378 patients treated with modern preoperative chemotherapy and hepatectomy were analyzed. The effect of positive margins on OS was analyzed in relation to pathologic and computed tomography-based morphologic response to chemotherapy. Results Fifty-two of 378 resections (14%) were R1 resections (tumor-free margin < 1 mm). The 5-year OS rates for patients with R0 resection (margin ≥ 1 mm) and R1 resection were 55% and 26%, respectively (P=0.017). Multivariate analysis identified R1 resection (P=0.03) and minor pathologic response to chemotherapy (P=0.002) as the 2 factors independently associated with worse survival. The survival benefit associated with negative margins (R0 vs. R1 resection) was greater in patients with suboptimal morphologic response (5-year OS rate: 62% vs. 11%, P=0.007) than in patients with optimal response (3-year OS rate: 92% vs. 88%, P=0.917) and greater in patients with minor pathologic response (5-year OS rate: 46% vs. 0%, P=0.002) than in patients with major response (5-year OS rate: 63% vs. 67%, P=0.587). Conclusions In the era of modern chemotherapy, negative margins remain an important determinant of survival and should be the primary goal of surgical therapy. The impact of positive margins is most pronounced in patients with suboptimal response to systemic therapy. PMID:23426338
Andreou, Andreas; Aloia, Thomas A; Brouquet, Antoine; Dickson, Paxton V; Zimmitti, Giuseppe; Maru, Dipen M; Kopetz, Scott; Loyer, Evelyne M; Curley, Steven A; Abdalla, Eddie K; Vauthey, Jean-Nicolas
2013-06-01
To determine the impact of surgical margin status on overall survival (OS) of patients undergoing hepatectomy for colorectal liver metastases after modern preoperative chemotherapy. In the era of effective chemotherapy for colorectal liver metastases, the association between surgical margin status and survival has become controversial. Clinicopathologic data and outcomes for 378 patients treated with modern preoperative chemotherapy and hepatectomy were analyzed. The effect of positive margins on OS was analyzed in relation to pathologic and computed tomography-based morphologic response to chemotherapy. Fifty-two of 378 resections (14%) were R1 resections (tumor-free margin <1 mm). The 5-year OS rates for patients with R0 resection (margin ≥1 mm) and R1 resection were 55% and 26%, respectively (P = 0.017). Multivariate analysis identified R1 resection (P = 0.03) and a minor pathologic response to chemotherapy (P = 0.002) as the 2 factors independently associated with worse survival. The survival benefit associated with negative margins (R0 vs R1 resection) was greater in patients with suboptimal morphologic response (5-year OS rate: 62% vs 11%; P = 0.007) than in patients with optimal response (3-year OS rate: 92% vs 88%; P = 0.917) and greater in patients with a minor pathologic response (5-year OS rate: 46% vs 0%; P = 0.002) than in patients with a major response (5-year OS rate: 63% vs 67%; P = 0.587). In the era of modern chemotherapy, negative margins remain an important determinant of survival and should be the primary goal of surgical therapy. The impact of positive margins is most pronounced in patients with suboptimal response to systemic therapy.
Wang, Ching-Yun; Cullings, Harry; Song, Xiao; Kopecky, Kenneth J.
2017-01-01
SUMMARY Observational epidemiological studies often confront the problem of estimating exposure-disease relationships when the exposure is not measured exactly. In the paper, we investigate exposure measurement error in excess relative risk regression, which is a widely used model in radiation exposure effect research. In the study cohort, a surrogate variable is available for the true unobserved exposure variable. The surrogate variable satisfies a generalized version of the classical additive measurement error model, but it may or may not have repeated measurements. In addition, an instrumental variable is available for individuals in a subset of the whole cohort. We develop a nonparametric correction (NPC) estimator using data from the subcohort, and further propose a joint nonparametric correction (JNPC) estimator using all observed data to adjust for exposure measurement error. An optimal linear combination estimator of JNPC and NPC is further developed. The proposed estimators are nonparametric, which are consistent without imposing a covariate or error distribution, and are robust to heteroscedastic errors. Finite sample performance is examined via a simulation study. We apply the developed methods to data from the Radiation Effects Research Foundation, in which chromosome aberration is used to adjust for the effects of radiation dose measurement error on the estimation of radiation dose responses. PMID:29354018
Hulshof, Catherine M; Stegen, James C; Swenson, Nathan G; Enquist, Carolyn A F; Enquist, Brian J
2012-01-01
Plants are expected to differentially allocate resources to reproduction, growth, and survival in order to maximize overall fitness. Life history theory predicts that the allocation of resources to reproduction should occur at the expense of vegetative growth. Although it is known that both organism size and resource availability can influence life history traits, few studies have addressed how size dependencies of growth and reproduction and variation in resource supply jointly affect the coupling between growth and reproduction. In order to understand the relationship between growth and reproduction in the context of resource variability, we utilize a long-term observational data set consisting of 670 individual trees over a 10-year period within a local population of Bursera simaruba (L.) Sarg. We (1) quantify the functional form and variability in the growth-reproduction relationship at the population and individual-tree level and (2) develop a theoretical framework to understand the allometric dependence of growth and reproduction. Our findings suggest that the differential responses of allometric growth and reproduction to resource availability, both between years and between microsites, underlie the apparent relationship between growth and reproduction. Finally, we offer an alternative approach for quantifying the relationship between growth and reproduction that accounts for variation in allometries.
Sakaguchi, Hirotoshi; Nishio, Nobuhiro; Hama, Asahito; Kawashima, Nozomu; Wang, Xinan; Narita, Atsushi; Doisaki, Sayoko; Xu, Yinyan; Muramatsu, Hideki; Yoshida, Nao; Takahashi, Yoshiyuki; Kudo, Kazuko; Moritake, Hiroshi; Nakamura, Kazuhiro; Kobayashi, Ryoji; Ito, Etsuro; Yabe, Hiromasa; Ohga, Shouichi; Ohara, Akira; Kojima, Seiji
2014-01-01
Predicting the response to immunosuppressive therapy could provide useful information to help the clinician define treatment strategies for patients with aplastic anemia. In our current study, we evaluated the relationship between telomere length of lymphocytes at diagnosis and the response to immunosuppressive therapy in 64 children with aplastic anemia, using flow fluorescence in situ hybridization. Median age of patients was ten years (range 1.5–16.2 years). Severity of the disease was classified as very severe in 23, severe in 21, and moderate in 20 patients. All patients were enrolled in multicenter studies using antithymocyte globulin and cyclosporine. The response rate to immunosuppressive therapy at six months was 52% (33 of 64). The probability of 5-year failure-free survival and overall survival were 56% (95% confidence interval (CI): 41–69%) and 97% (95%CI: 87–99%), respectively. Median telomere length in responders was −0.4 standard deviation (SD) (−2.7 to +3.0 SD) and −1.5 SD (−4.0 to +1.6 (SD)) in non-responders (P<0.001). Multivariate analysis showed that telomere length shorter than −1.0 SD (hazard ratio (HR): 22.0; 95%CI: 4.19–115; P<0.001), platelet count at diagnosis less than 25×109/L (HR: 13.9; 95%CI: 2.00–96.1; P=0.008), and interval from diagnosis to immunosuppressive therapy longer than 25 days (HR: 4.81; 95%CI: 1.15–20.1; P=0.031) were the significant variables for poor response to immunosuppressive therapy. Conversely to what has been found in adult patients, measurement of the telomere length of lymphocytes at diagnosis is a promising assay in predicting the response to immunosuppressive therapy in children with aplastic anemia. PMID:24816243