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  1. Antimicrobial resistances do not affect colonization parameters of intestinal E. coli in a small piglet group

    PubMed Central

    Schierack, Peter; Kadlec, Kristina; Guenther, Sebastian; Filter, Matthias; Schwarz, Stefan; Ewers, Christa; Wieler, Lothar H

    2009-01-01

    Background Although antimicrobial resistance and persistence of resistant bacteria in humans and animals are major health concerns worldwide, the impact of antimicrobial resistance on bacterial intestinal colonization in healthy domestic animals has only been rarely studied. We carried out a retrospective analysis of the antimicrobial susceptibility status and the presence of resistance genes in intestinal commensal E. coli clones from clinically healthy pigs from one production unit with particular focus on effects of pheno- and/or genotypic resistance on different nominal and numerical intestinal colonization parameters. In addition, we compared the occurrence of antimicrobial resistance phenotypes and genotypes with the occurrence of virulence associated genes typical for extraintestinal pathogenic E. coli. Results In general, up to 72.1% of all E. coli clones were resistant to ampicillin, chloramphenicol, kanamycin, streptomycin, sulfamethoxazole or tetracycline with a variety of different resistance genes involved. There was no significant correlation between one of the nominal or numerical colonization parameters and the absence or presence of antimicrobial resistance properties or resistance genes. However, there were several statistically significant associations between the occurrence of single resistance genes and single virulence associated genes. Conclusion The demonstrated resistance to the tested antibiotics might not play a dominant role for an intestinal colonization success in pigs in the absence of antimicrobial drugs, or cross-selection of other colonization factors e.g. virulence associated genes might compensate "the cost of antibiotic resistance". Nevertheless, resistant strains are not outcompeted by susceptible bacteria in the porcine intestine. Trial Registration The study was approved by the local animal welfare committee of the "Landesamt für Arbeitsschutz, Gesundheitsschutz und technische Sicherheit" Berlin, Germany (No. G0037/02). PMID

  2. ANALYSIS OF BIOMECHANICAL PARAMETERS IN COLONIC ANASTOMOSIS

    PubMed Central

    IWANAGA, Tiago Cavalcanti; AGUIAR, José Lamartine de Andrade; MARTINS-FILHO, Euclides Dias; KREIMER, Flávio; SILVA-FILHO, Fernando Luiz; de ALBUQUERQUE, Amanda Vasconcelos

    2016-01-01

    ABSTRACT Background: The use of measures in colonic anastomoses to prevent dehiscences is of great medical interest. Sugarcane molasses, which has adequate tolerability and compatibility in vivo, has not yet been tested for this purpose. Aim: To analyze the biomechanical parameters of colonic suture in rats undergoing colectomy, using sugarcane molasses polysaccharide as tape or gel. Methods: 45 Wistar rats (Rattus norvegicus albinus) were randomized into three groups of 15 animals: irrigation of enteric sutures with 0.9% saline solution; application of sugarcane molasses polysaccharide as tape; and sugarcane molasses polysaccharide as gel. The rats underwent colon ressection, with subsequent reanastomosis using polypropylene suture; they were treated according to their respective groups. Five rats from each group were evaluated at different times after the procedure: 30, 90 and 180 days postoperatively. The following variables were evaluated: maximum rupture force, modulus of elasticity and specific deformation of maximum force. Results: The biomechanical variables among the scheduled times and treatment groups were statistically calculated. The characteristics of maximum rupture force and modulus of elasticity of the specimens remained identical, regardless of treatment with saline, polysaccharide gel or tape, and treatment time. However, it was found that the specific deformation of maximum force of the intestinal wall was higher after 180 days in the group treated with sugarcane polysaccharide gel (p=0.09). Conclusion: Compared to control, it was detected greater elasticity of the intestinal wall in mice treated with sugarcane polysaccharide gel, without changing other biomechanical characteristics, regardless of type or time of treatment. PMID:27438033

  3. Indocyanine green alters transepithelial electrical parameters of the distal colon.

    PubMed

    Hameed, Burhan; Smith, David M; Verrechio, Jon J; Schmidt, J David; Gillooley, Leesa E; Valenzano, Mary Carmen; Lewis, Simon A; Mullin, James M

    2004-09-01

    Indocyanine green (ICG) is used as a dye marker of the vascular space in gastroenterology, ophthalmology, neurology, and critical care medicine. It is widely regarded to be inert. We report, however, that ICG demonstrates effects on colonic transepithelial electrical parameters which could form a basis for a growing number of deleterious gastrointestinal and other clinical effects. Short-circuit current (Iscc), transepithelial conductance (gt), and transepithelial paracellular flux of 14C-D-mannitol were monitored across sheets of rat distal colon. Dye was introduced to mucosal or serosal tissue surfaces at a concentration similar to that used in vivo (10 microg/ml). ICG decreased Iscc by over 50% and gt by over 10%. Transepithelial mannitol flux was not altered. Dye was effective only from the serosal surface. Cyclic AMP-induced spiking of Iscc was not affected by ICG. Preincubation with amiloride or furosemide did not affect the action of the dye on gt or Iscc. ICG at in vivo dosages is clearly capable of inhibiting ion transport across colon epithelial tissue. The serosal site of action indicates activity on a basal-lateral transport system or diffusion into the cell only across the basal-lateral membrane followed by inhibition of a transporter from the intracellular side. ICG should not be considered inert in vivo. Leakage of ICG from the vascular space into the interstitial fluid space will likely result in tissue morbidity. PMID:15481307

  4. Biobanking of Fresh-Frozen Human Adenocarcinomatous and Normal Colon Tissues: Which Parameters Influence RNA Quality?

    PubMed

    Galissier, Thibaut; Schneider, Christophe; Nasri, Saviz; Kanagaratnam, Lukshe; Fichel, Caroline; Coquelet, Christelle; Diebold, Marie-Danièle; Kianmanesh, Reza; Bellon, Georges; Dedieu, Stéphane; Marchal Bressenot, Aude; Boulagnon-Rombi, Camille

    2016-01-01

    Medical research projects become increasingly dependent on biobanked tissue of high quality because the reliability of gene expression is affected by the quality of extracted RNA. Hence, the present study aimed to determine if clinical, surgical, histological, and molecular parameters influence RNA quality of normal and tumoral frozen colonic tissues. RNA Quality Index (RQI) was evaluated on 241 adenocarcinomas and 115 matched normal frozen colon tissues collected between October 2006 and December 2012. RQI results were compared to patients' age and sex, tumor site, kind of surgery, anastomosis failure, adenocarcinoma type and grade, tumor cell percentage, necrosis extent, HIF-1α and cleaved caspase-3 immunohistochemistry, and BRAF, KRAS and microsatellites status. The RQI was significantly higher in colon cancer tissue than in matched normal tissue. RQI from left-sided colonic cancers was significantly higher than RQI from right-sided cancers. The RNA quality was not affected by ischemia and storage duration. According to histological control, 7.9% of the samples were unsatisfactory because of inadequate sampling. Biobanked tumoral tissues with RQI ≥5 had lower malignant cells to stromal cells ratio than samples with RQI <5 (p <0.05). Cellularity, necrosis extent and mucinous component did not influence RQI results. Cleaved caspase-3 and HIF-1α immunolabelling were not correlated to RQI. BRAF, KRAS and microsatellites molecular status did not influence RNA quality. Multivariate analysis revealed that the tumor location, the surgical approach (laparoscopy versus open colectomy) and the occurrence of anastomotic leakage were the only parameters influencing significantly RQI results of tumor samples. We failed to identify parameter influencing RQI of normal colon samples. These data suggest that RNA quality of colonic adenocarcinoma biospecimens is determined by clinical and surgical parameters. More attention should be paid during the biobanking procedure of

  5. Biobanking of Fresh-Frozen Human Adenocarcinomatous and Normal Colon Tissues: Which Parameters Influence RNA Quality?

    PubMed Central

    Galissier, Thibaut; Schneider, Christophe; Nasri, Saviz; Kanagaratnam, Lukshe; Fichel, Caroline; Coquelet, Christelle; Diebold, Marie-Danièle; Kianmanesh, Reza; Bellon, Georges; Dedieu, Stéphane; Marchal Bressenot, Aude

    2016-01-01

    Medical research projects become increasingly dependent on biobanked tissue of high quality because the reliability of gene expression is affected by the quality of extracted RNA. Hence, the present study aimed to determine if clinical, surgical, histological, and molecular parameters influence RNA quality of normal and tumoral frozen colonic tissues. RNA Quality Index (RQI) was evaluated on 241 adenocarcinomas and 115 matched normal frozen colon tissues collected between October 2006 and December 2012. RQI results were compared to patients’ age and sex, tumor site, kind of surgery, anastomosis failure, adenocarcinoma type and grade, tumor cell percentage, necrosis extent, HIF-1α and cleaved caspase-3 immunohistochemistry, and BRAF, KRAS and microsatellites status. The RQI was significantly higher in colon cancer tissue than in matched normal tissue. RQI from left-sided colonic cancers was significantly higher than RQI from right-sided cancers. The RNA quality was not affected by ischemia and storage duration. According to histological control, 7.9% of the samples were unsatisfactory because of inadequate sampling. Biobanked tumoral tissues with RQI ≥5 had lower malignant cells to stromal cells ratio than samples with RQI <5 (p <0.05). Cellularity, necrosis extent and mucinous component did not influence RQI results. Cleaved caspase-3 and HIF-1α immunolabelling were not correlated to RQI. BRAF, KRAS and microsatellites molecular status did not influence RNA quality. Multivariate analysis revealed that the tumor location, the surgical approach (laparoscopy versus open colectomy) and the occurrence of anastomotic leakage were the only parameters influencing significantly RQI results of tumor samples. We failed to identify parameter influencing RQI of normal colon samples. These data suggest that RNA quality of colonic adenocarcinoma biospecimens is determined by clinical and surgical parameters. More attention should be paid during the biobanking procedure of

  6. Tobacco smoking affects bacterial acquisition and colonization in oral biofilms.

    PubMed

    Kumar, Purnima S; Matthews, Chad R; Joshi, Vinayak; de Jager, Marko; Aspiras, Marcelo

    2011-11-01

    Recent evidence suggests that smoking affects the composition of the disease-associated subgingival biofilm, yet little is known about its effects during the formation of this biofilm. The present investigation was undertaken to examine the contributions of smoking to the composition and proinflammatory characteristics of the biofilm during de novo plaque formation. Marginal and subgingival plaque and gingival crevicular fluid samples were collected from 15 current smokers and from 15 individuals who had never smoked (nonsmokers) following 1, 2, 4, and 7 days of undisturbed plaque formation. 16S rRNA gene cloning and sequencing were used for bacterial identification, and multiplex bead-based flow cytometry was used to quantify the levels of 27 immune mediators. Smokers demonstrated a highly diverse, relatively unstable initial colonization of both marginal and subgingival biofilms, with lower niche saturation than that seen in nonsmokers. Periodontal pathogens belonging to the genera Fusobacterium, Cardiobacterium, Synergistes, and Selenomonas, as well as respiratory pathogens belonging to the genera Haemophilus and Pseudomonas, colonized the early biofilms of smokers and continued to persist over the observation period, suggesting that smoking favors early acquisition and colonization of pathogens in oral biofilms. Smokers also demonstrated an early proinflammatory response to this colonization, which persisted over 7 days. Further, a positive correlation between proinflammatory cytokine levels and commensal bacteria was observed in smokers but not in nonsmokers. Taken together, the data suggest that smoking influences both the composition of the nascent biofilm and the host response to this colonization.

  7. Modelling affect in terms of speech parameters.

    PubMed

    Stassen, H H

    1988-01-01

    It is well known that the human voice contains important information about the affective state of a speaker at a nonverbal level. Accordingly, we started an extensive investigation which aims at modelling intraindividual changes of the global affective state over time, as this state is reflected by the human voice, and can be inferred from measurable speech parameters. For the purpose of this investigation, a speech-recording procedure was designed which is especially suited to reveal intraindividual changes of voice patterns over time since each person serves as his or her own reference. On the other hand, the chosen experimental setup is less suited to classify patients in the sense of a traditional diagnostic scheme. In order to find an appropriate mathematical model on the basis of speech parameters, a calibration study with 190 healthy subjects was carried out which enabled us to investigate each parameter for its reproducibility, sensitivity and specificity. In particular, this calibration study yielded the information of how to draw the line between 'normal' fluctuations and 'significant' intraindividual changes over time. All speech parameters under discussion turned out to be sufficiently stable over time, whereas, in regard to their sensitivity to form and content of text, significant differences showed up. In a second step, a pilot study with 6 depressive patients was carried out in order to investigate the specificity of voice parameters with regard to psychopathology. It turned out that the registration procedure is realizable even if patients are considerably handicapped by their illness. However, no consistent correlations could be revealed between single speech parameters and psychopathological rating scales.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Yersinia enterocolitica Affects Intestinal Barrier Function in the Colon.

    PubMed

    Hering, Nina A; Fromm, Anja; Kikhney, Judith; Lee, In-Fah M; Moter, Annette; Schulzke, Jörg D; Bücker, Roland

    2016-04-01

    Infection with Yersinia enterocolitica causes acute diarrhea in early childhood. A mouse infection model presents new findings on pathological mechanisms in the colon. Symptoms involve diarrhea with watery feces and weight loss that have their functional correlates in decreased transepithelial electrical resistance and increased fluorescein permeability. Y. enterocolitica was present within the murine mucosa of both ileum and colon. Here, the bacterial insult was of focal nature and led to changes in tight junction protein expression and architecture. These findings are in concordance with observations from former cell culture studies and suggest a leak flux mechanism of diarrhea.

  9. Physical parameters affecting living cells in space

    NASA Astrophysics Data System (ADS)

    Langbein, Dieter

    The question is posed: Why does a living cell react to the absence of gravity? What sensors may it have? Does it note pressure, sedimentation, convection, or other parameters? If somewhere in a liquid volume sodium ions are replaced by potassium ions, the density of the liquid changes locally: the heavier regions sink, the lighter regions rise. This may contribute to species transport, to the metabolism. Under microgravity this mechanism is strongly reduced. On the other hand, other reasons for convection like thermal and solutal interface convection are left. Do they affect species transport? Another important effect of gravity is the hydrostatic pressure. On the macroscopic side, the pressure between our head and feet changes by 0.35 atmospheres. On the microscopic level the hydrostatic pressure on the upper half of a cell membrane is lower than on the lower half. This, by affecting the ion transport through the membrane, may change the surrounding electric potential. It has been suggested to be one of the reasons for graviperception. Following the discussion of these and other effects possibly important in life sciences in space, an order of magnitude analysis of the residual accelerations tolerable during experiments in materials sciences is outlined. In the field of life sciences only rough estimates are available at present.

  10. The influence of distal colon irritation on the changes of cystometry parameters to esophagus and colon distentions

    PubMed Central

    Kaddumi, Ezidin G.

    2016-01-01

    ABSTRACT The co-occurrence of multiple pathologies in the pelvic viscera in the same patient, such as, irritable bowel syndrome and interstitial cystitis, indicates the complexity of viscero-visceral interactions and the necessity to study these interactions under multiple pathological conditions. In the present study, the effect of distal colon irritation (DCI) on the urinary bladder interaction with distal esophagus distention (DED), distal colon distention (DCD), and electrical stimulation of the abdominal branches of vagus nerve (abd-vagus) were investigated using cystometry parameters. The DCI significantly decreased the intercontraction time (ICT) by decreasing the storage time (ST); nonetheless, DED and Abd-vagus were still able to significantly decrease the ICT and ST following DCI. However, DCD had no effect on ICT following the DCI. The DCI, also, significantly decreased the Intravesical pressure amplitude (P-amplitude) by increasing the resting pressure (RP). Although DED has no effect on the P-amplitude, both in the intact and the irritated animals, the abd-vagus significantly increased the P-amplitude following DCI by increasing the maximum pressure (MP). In the contrary, 3mL DCD significantly increased the P-amplitude by increasing the MP and lost that effect following the DCI. Concerning the pressure threshold (PT), none of the stimuli had any significant changes in the intact animals. However, DCI significantly decreased the PT, also, the abd-vagus and 3mL DCD significantly decreased the PT. The results of this study indicate that chemical irritation of colon complicates the effects of mechanical irritation of esophagus and colon on urinary bladder function. PMID:27286126

  11. The influence of distal colon irritation on the changes of cystometry parameters to esophagus and colon distentions.

    PubMed

    Kaddumi, Ezidin G

    2016-01-01

    The co-occurrence of multiple pathologies in the pelvic viscera in the same patient, such as, irritable bowel syndrome and interstitial cystitis, indicates the complexity of viscero-visceral interactions and the necessity to study these interactions under multiple pathological conditions. In the present study, the effect of distal colon irritation (DCI) on the urinary bladder interaction with distal esophagus distention (DED), distal colon distention (DCD), and electrical stimulation of the abdominal branches of vagus nerve (abd-vagus) were investigated using cystometry parameters. The DCI significantly decreased the intercontraction time (ICT) by decreasing the storage time (ST); nonetheless, DED and Abd-vagus were still able to significantly decrease the ICT and ST following DCI. However, DCD had no effect on ICT following the DCI. The DCI, also, significantly decreased the Intravesical pressure amplitude (P-amplitude) by increasing the resting pressure (RP). Although DED has no effect on the P-amplitude, both in the intact and the irritated animals, the abd-vagus significantly increased the P-amplitude following DCI by increasing the maximum pressure (MP). In the contrary, 3mL DCD significantly increased the P-amplitude by increasing the MP and lost that effect following the DCI. Concerning the pressure threshold (PT), none of the stimuli had any significant changes in the intact animals. However, DCI significantly decreased the PT, also, the abd-vagus and 3mL DCD significantly decreased the PT. The results of this study indicate that chemical irritation of colon complicates the effects of mechanical irritation of esophagus and colon on urinary bladder function. PMID:27286126

  12. Factors Affecting Staphylococcus aureus Colonization of the Nasopharynx in the First Six Months of Life

    PubMed Central

    Patel, Janak A; Alvarez-Fernandez, Pedro; Jennings, Kristofer; Loeffelholz, Michael; McCormick, David; Chonmaitree, Tasnee

    2015-01-01

    Background Staphylococcal aureus (SA) colonization in early infancy is common, but the pattern and factors affecting its acquisition and persistence in the first few months of life are not well studied. Objectives To study the rate of SA nasopharyngeal (NP) colonization at monthly intervals in the first six months of life, and its association with environmental and host factors, and other pathogenic NP bacteria. Methods Data from a prospective study were analyzed on bacterial cultures of 1765 NP swabs from 367 infants who were followed from birth to 6 months of age. Demographic, breastfeeding, cigarette smoke exposure and daycare attendance data were collected at each monthly visit. Results The rate of infants colonized with SA was highest at age 1 month (25%) and declined to lowest rate by age 6 months (12%). The proportion of SA strains that was methicillin-resistant (MRSA) was also highest at age 1 month and declined rapidly by age 4 months (18% vs 6%, P = 0.05). Colonization with Streptococcus pneumoniae (SP), nontypeable Haemophilus influenzae (HI) and Moraxella catarrhalis (MC) increased at different rates up to age 6 months. Univariate analysis showed that SA colonization rate was significantly lower with increasing age, black race, day care attendance, and colonization with NTHI, MC and SP (P <0.05). Multivariate analysis showed that this effect was independently associated only with increasing age and MC colonization (P ≤0.05). Furthermore, the time to first acquisition of SA from one month of age onwards was significantly associated with day care attendance, and NTHI and MC colonization. None of the infants colonized with SA developed SA infections through age 6 months. Conclusions SA colonization of NP begins very early in life and declines quickly. MRSA has lower ability to maintain prolonged colonization status than methicillin-susceptible strains in the first 6 months of life. As the NP is colonized with other respiratory bacterial pathogens, the

  13. Biotic interactions affect the colonization behavior of aquatic detritivorous macroinvertebrates in a heterogeneous environment

    NASA Astrophysics Data System (ADS)

    Verschut, Thomas A.; Meineri, Eric; Basset, Alberto

    2015-05-01

    It has previously been suggested that macroinvertebrates actively search for suitable patches to colonize. However, it is not well understood how the spatial arrangement of patches can affect colonization rates. In this study, we determined the importance of the environmental factors (distance, connectivity and resource availability) for patch colonization in an experimental system using Gammarus aequicauda (Amphipoda), Lekanesphaera hookeri (Isopoda) and Ecrobia ventrosa (Gastropoda). Furthermore, we also assessed how the relative importance of each of these environmental factors differed in interactions between the three species. The single species experiments showed that distance was the most important factor for G. aequicauda and E. ventrosa. However, while E. ventrosa preferred patches close to the release point, G. aequicauda strongly preferred patches further from the release point. High resource availability was a strong determinant for the patch colonization of G. aequicauda and L. hookeri. Connectivity was only of moderate importance in the study system for L. hookeri and E. ventrosa. The effects of the environmental factors were strongly affected by interspecific interactions in the multispecies experiments. For G. aequicauda, the distance preference was lowered in the presence of E. ventrosa. Moreover, while for L. hookeri the effect of resource availability was ruled out by the species interactions, resource availability gained importance for E. ventrosa in the presence of any of the other species. Our results suggest a strong link between environmental factors and biotic interactions in the colonization of habitat patches and indicate that the effect of biotic interactions is especially important for species sharing similar traits.

  14. Does posture affect cystometric parameters and diagnoses?

    PubMed

    Arunkalaivanan, A S; Mahomoud, S; Howell, M

    2004-01-01

    The objective of this study was to investigate the effect of lying and sitting positions on urodynamic parameters and diagnoses. This prospective study was carried out on 96 women with urinary incontinence who underwent urodynamic assessment. Cystometry was performed both in the lying and sitting positions. For filling cystometry, we infused normal saline at a rate of 50 ml/min. All the results were entered on the urodynamic database and were analysed using Minitab software release 13.30. Mean age was 49 (20-84) years. Sixty-four (67%) women complained of mixed incontinence, 16 (17%) of urgency alone, eight (8%) of stress incontinence and eight (8%) of urgency and urge incontinence. Two (2%) showed stress incontinence by lying cystometry, and 53 (55%) by sitting cystometry. During lying nine (9%) demonstrated detrusor overactivity, while 53 (55%) demonstrated detrusor overactivity in sitting position. No case of mixed incontinence was diagnosed by lying cystometry but 17 (18%) cases were detected by sitting cystometry. This study explains the higher detection rate of stress incontinence, detrusor overactivity and mixed incontinence by cystometry in sitting position. Therefore, we recommend that sitting posture is preferred over lying position for performing cystometry.

  15. Terahertz absorption and reflection imaging of carcinoma-affected colon tissues embedded in paraffin

    NASA Astrophysics Data System (ADS)

    Wahaia, Faustino; Kasalynas, Irmantas; Venckevicius, Rimvydas; Seliuta, Dalius; Valusis, Gintaras; Urbanowicz, Andrzej; Molis, Gediminas; Carneiro, Fatima; Carvalho Silva, Catia D.; Granja, Pedro L.

    2016-03-01

    In the present study, dehydrated human colon tissues embedded in paraffin were studied at THz frequency. A compact THz imaging system with high numerical aperture optics was developed for the analysis of adenocarcinoma-affected colon sections, in transmission and reflection geometry. A comprehensive analysis of the THz images revealed a contrast up to 23% between the neoplastic and control tissues. Absorption and reflection THz images demonstrated the possibility to distinguish adenocarcinoma-affected areas even without water in the tissue, as the main contrast mechanism in THz measurements has been observed to be water absorption in in vivo or freshly excised tissues. The present results corroborate with previous histologic findings in the same tissues, and confirm that the contrast prevails even in dehydrated tissues.

  16. Host-related metabolic cues affect colonization strategies of a root endophyte

    PubMed Central

    Lahrmann, Urs; Ding, Yi; Banhara, Aline; Rath, Magnus; Hajirezaei, Mohammad R.; Döhlemann, Stefanie; von Wirén, Nicolaus; Parniske, Martin; Zuccaro, Alga

    2013-01-01

    The mechanisms underpinning broad compatibility in root symbiosis are largely unexplored. The generalist root endophyte Piriformospora indica establishes long-lasting interactions with morphologically and biochemically different hosts, stimulating their growth, alleviating salt stress, and inducing local and systemic resistance to pathogens. Cytological studies and global investigations of fungal transcriptional responses to colonization of barley and Arabidopsis at different symbiotic stages identified host-dependent colonization strategies and host-specifically induced effector candidates. Here, we show that in Arabidopsis, P. indica establishes and maintains biotrophic nutrition within living epidermal cells, whereas in barley the symbiont undergoes a nutritional switch to saprotrophy that is associated with the production of secondary thinner hyphae in dead cortex cells. Consistent with a diversified trophic behavior and with the occurrence of nitrogen deficiency at the onset of saprotrophy in barley, fungal genes encoding hydrolytic enzymes and nutrient transporters were highly induced in this host but not in Arabidopsis. Silencing of the high-affinity ammonium transporter PiAMT1 gene, whose transcripts are accumulating during nitrogen starvation and in barley, resulted in enhanced colonization of this host, whereas it had no effect on the colonization of Arabidopsis. Increased levels of free amino acids and reduced enzymatic activity for the cell-death marker VPE (vacuolar-processing enzyme) in colonized barley roots coincided with an extended biotrophic lifestyle of P. indica upon silencing of PiAMT1. This suggests that PiAmt1 functions as a nitrogen sensor mediating the signal that triggers the in planta activation of the saprotrophic program. Thus, host-related metabolic cues affect the expression of P. indica’s alternative lifestyles. PMID:23918389

  17. Colon cancer: association of histopathological parameters and patients' survival with clinical presentation.

    PubMed

    Alexiusdottir, Kristin K; Snaebjornsson, Petur; Tryggvadottir, Laufey; Jonasson, Larus; Olafsdottir, Elinborg J; Björnsson, Einar Stefan; Möller, Pall Helgi; Jonasson, Jon G

    2013-10-01

    Available data correlating symptoms of colon cancer patients with the severity of the disease are very limited. In a population-based setting, we correlated information on symptoms of colon cancer patients with several pathological tumor parameters and survival. Information on all patients diagnosed with colon cancer in Iceland in 1995-2004 for this retrospective, population-based study was obtained from the Icelandic Cancer Registry. Information on symptoms of patients and blood hemoglobin was collected from patients' files. Pathological parameters were obtained from a previously performed standardized tumor review. A total of 768 patients entered this study; the median age was 73 years. Tumors in patients presenting at diagnosis with visible blood in stools were significantly more likely to be of lower grade, having pushing border, conspicuous peritumoral lymphocytic infiltration, and lower frequency of vessel invasion. Patients with abdominal pain and anemia were significantly more likely to have vessel invasion. Logistic regression showed that visible blood in stools was significantly associated with protecting pathological factors (OR range 0.38-0.83, p < 0.05). Tumors in patients presenting with abdominal pain were strongly associated with infiltrative margin and scarce peritumoral lymphocytic infiltration (OR = 1.95; 2.18 respectively, p < 0.05). Changes in bowel habits were strongly associated with vessel invasion (OR = 2.03, p < 0.05). Cox regression showed that blood in stools predicted survival (HR = 0.54). In conclusion, visible blood in stools correlates significantly with all the beneficial pathological parameters analyzed and with better survival of patients. Anemia, general symptoms, changes in bowel habits, acute symptoms, and abdominal pain correlate with more aggressive tumor characteristics and adverse outcome for patients.

  18. Cecal volatile fatty acids and broiler chick susceptibility to Salmonella typhimurium colonization as affected by aflatoxins and T-2 toxin.

    PubMed

    Kubena, L F; Bailey, R H; Byrd, J A; Young, C R; Corrier, D E; Stanker, L H; Rottinghaust, G E

    2001-04-01

    Four experiments were conducted using day-of-hatch, mixed-sex broiler chicks to evaluate the effects of aflatoxins and T-2 toxin on cecal volatile fatty acids (VFA) and the susceptibility to Salmonella colonization. All chicks in these experiments were challenged orally with 10(4) cfu of Salmonella typhimurium (ST) on Day 3. In Experiments 1 and 2, chicks were fed diets containing 0, 2.5, or 7.5 mg aflatoxins/kg of diet and were allowed to develop their microflora naturally. In Experiment 3, all chicks were orally gavaged on the day of hatch with a competitive exclusion (CE) culture (PREEMPT) and were fed diets containing 0, 2.5, or 7.5 mg T-2 toxin/kg. In Experiment 4, the chicks were fed diets containing 0, 7.5, or 15.0 mg T-2 toxin/kg and one-half of the chicks were orally gavaged on the day of hatch with the CE culture. In Experiments 1 and 2, with the exception of increased total VFA at 5 d in chicks fed the 7.5 mg T-2 aflatoxins/kg diet, there were no treatment effects on cecal propionic acid, total VFA, or incidence or severity of ST colonization. In Experiment 3, the only alteration in concentration of cecal propionic acid or total VFA was a significant reduction in total VFA at 5 d in chicks fed the 2.5 mg T-2 toxin/kg diet. No significant treatment differences were observed for numbers of Salmonella cecal culture-positive chicks or for numbers of ST in the cecal contents. In Experiment 4, with minor exceptions, the chicks treated with the CE culture had higher cecal concentrations of propionic acid and were less susceptible to Salmonella colonization than the non-CE-treated chicks. In the non-CE-treated chicks, T-2 toxin had no effect on any of the parameters, and 85 to 90% of the chicks were Salmonella cecal culture-positive. In the CE-treated chicks, there was a decrease in propionic acid concentration at 3 and 11 d and an increase in susceptibility to Salmonella colonization of the chicks fed the 15.0 mg T-2 toxin/kg diet. These results indicate that

  19. A review of the meteorological parameters which affect aerial application

    NASA Technical Reports Server (NTRS)

    Christensen, L. S.; Frost, W.

    1979-01-01

    The ambient wind field and temperature gradient were found to be the most important parameters. Investigation results indicated that the majority of meteorological parameters affecting dispersion were interdependent and the exact mechanism by which these factors influence the particle dispersion was largely unknown. The types and approximately ranges of instrumented capabilities for a systematic study of the significant meteorological parameters influencing aerial applications were defined. Current mathematical dispersion models were also briefly reviewed. Unfortunately, a rigorous dispersion model which could be applied to aerial application was not available.

  20. Campylobacter jejuni pdxA Affects Flagellum-Mediated Motility to Alter Host Colonization

    PubMed Central

    Asakura, Hiroshi; Hashii, Noritaka; Uema, Masashi; Kawasaki, Nana; Sugita-Konishi, Yoshiko; Igimi, Shizunobu; Yamamoto, Shigeki

    2013-01-01

    Vitamin B6 (pyridoxal-5'-phosphate, PLP) is linked to a variety of biological functions in prokaryotes. Here, we report that the pdxA (putative 4-hydroxy-L-threonine phosphate dehydrogenase) gene plays a pivotal role in the PLP-dependent regulation of flagellar motility, thereby altering host colonization in a leading foodborne pathogen, Campylobacter jejuni. A C. jejuni pdxA mutant failed to produce PLP and exhibited a coincident loss of flagellar motility. Mass spectrometric analyses showed a 3-fold reduction in the main flagellar glycan pseudaminic acid (Pse) associated with the disruption of pdxA. The pdxA mutant also exhibited reduced growth rates compared with the WT strain. Comparative metabolomic analyses revealed differences in respiratory/energy metabolism between WT C. jejuni and the pdxA mutant, providing a possible explanation for the differential growth fitness between the two strains. Consistent with the lack of flagellar motility, the pdxA mutant showed impaired motility-mediated responses (bacterial adhesion, ERK1/2 activation, and IL-8 production) in INT407 cells and reduced colonization of chickens compared with the WT strain. Overall, this study demonstrated that the pdxA gene affects the PLP-mediated flagellar motility function, mainly through alteration of Pse modification, and the disruption of this gene also alters the respiratory/energy metabolisms to potentially affect host colonization. Our data therefore present novel implications regarding the utility of PLP and its dependent enzymes as potent target(s) for the control of this pathogen in the poultry host. PMID:23936426

  1. Oxygen Affects Gut Bacterial Colonization and Metabolic Activities in a Gnotobiotic Cockroach Model

    PubMed Central

    Tegtmeier, Dorothee; Thompson, Claire L.; Schauer, Christine

    2015-01-01

    The gut microbiota of termites and cockroaches represents complex metabolic networks of many diverse microbial populations. The distinct microenvironmental conditions within the gut and possible interactions among the microorganisms make it essential to investigate how far the metabolic properties of pure cultures reflect their activities in their natural environment. We established the cockroach Shelfordella lateralis as a gnotobiotic model and inoculated germfree nymphs with two bacterial strains isolated from the guts of conventional cockroaches. Fluorescence microscopy revealed that both strains specifically colonized the germfree hindgut. In diassociated cockroaches, the facultatively anaerobic strain EbSL (a new species of Enterobacteriaceae) always outnumbered the obligately anaerobic strain FuSL (a close relative of Fusobacterium varium), irrespective of the sequence of inoculation, which showed that precolonization by facultatively anaerobic bacteria does not necessarily favor colonization by obligate anaerobes. Comparison of the fermentation products of the cultures formed in vitro with those accumulated in situ indicated that the gut environment strongly affected the metabolic activities of both strains. The pure cultures formed the typical products of mixed-acid or butyrate fermentation, whereas the guts of gnotobiotic cockroaches accumulated mostly lactate and acetate. Similar shifts toward more-oxidized products were observed when the pure cultures were exposed to oxygen, which corroborated the strong effects of oxygen on the metabolic fluxes previously observed in termite guts. Oxygen microsensor profiles of the guts of germfree, gnotobiotic, and conventional cockroaches indicated that both gut tissue and microbiota contribute to oxygen consumption and suggest that the oxygen status influences the colonization success. PMID:26637604

  2. Oxygen Affects Gut Bacterial Colonization and Metabolic Activities in a Gnotobiotic Cockroach Model.

    PubMed

    Tegtmeier, Dorothee; Thompson, Claire L; Schauer, Christine; Brune, Andreas

    2016-02-01

    The gut microbiota of termites and cockroaches represents complex metabolic networks of many diverse microbial populations. The distinct microenvironmental conditions within the gut and possible interactions among the microorganisms make it essential to investigate how far the metabolic properties of pure cultures reflect their activities in their natural environment. We established the cockroach Shelfordella lateralis as a gnotobiotic model and inoculated germfree nymphs with two bacterial strains isolated from the guts of conventional cockroaches. Fluorescence microscopy revealed that both strains specifically colonized the germfree hindgut. In diassociated cockroaches, the facultatively anaerobic strain EbSL (a new species of Enterobacteriaceae) always outnumbered the obligately anaerobic strain FuSL (a close relative of Fusobacterium varium), irrespective of the sequence of inoculation, which showed that precolonization by facultatively anaerobic bacteria does not necessarily favor colonization by obligate anaerobes. Comparison of the fermentation products of the cultures formed in vitro with those accumulated in situ indicated that the gut environment strongly affected the metabolic activities of both strains. The pure cultures formed the typical products of mixed-acid or butyrate fermentation, whereas the guts of gnotobiotic cockroaches accumulated mostly lactate and acetate. Similar shifts toward more-oxidized products were observed when the pure cultures were exposed to oxygen, which corroborated the strong effects of oxygen on the metabolic fluxes previously observed in termite guts. Oxygen microsensor profiles of the guts of germfree, gnotobiotic, and conventional cockroaches indicated that both gut tissue and microbiota contribute to oxygen consumption and suggest that the oxygen status influences the colonization success. PMID:26637604

  3. Oxygen Affects Gut Bacterial Colonization and Metabolic Activities in a Gnotobiotic Cockroach Model.

    PubMed

    Tegtmeier, Dorothee; Thompson, Claire L; Schauer, Christine; Brune, Andreas

    2015-12-04

    The gut microbiota of termites and cockroaches represents complex metabolic networks of many diverse microbial populations. The distinct microenvironmental conditions within the gut and possible interactions among the microorganisms make it essential to investigate how far the metabolic properties of pure cultures reflect their activities in their natural environment. We established the cockroach Shelfordella lateralis as a gnotobiotic model and inoculated germfree nymphs with two bacterial strains isolated from the guts of conventional cockroaches. Fluorescence microscopy revealed that both strains specifically colonized the germfree hindgut. In diassociated cockroaches, the facultatively anaerobic strain EbSL (a new species of Enterobacteriaceae) always outnumbered the obligately anaerobic strain FuSL (a close relative of Fusobacterium varium), irrespective of the sequence of inoculation, which showed that precolonization by facultatively anaerobic bacteria does not necessarily favor colonization by obligate anaerobes. Comparison of the fermentation products of the cultures formed in vitro with those accumulated in situ indicated that the gut environment strongly affected the metabolic activities of both strains. The pure cultures formed the typical products of mixed-acid or butyrate fermentation, whereas the guts of gnotobiotic cockroaches accumulated mostly lactate and acetate. Similar shifts toward more-oxidized products were observed when the pure cultures were exposed to oxygen, which corroborated the strong effects of oxygen on the metabolic fluxes previously observed in termite guts. Oxygen microsensor profiles of the guts of germfree, gnotobiotic, and conventional cockroaches indicated that both gut tissue and microbiota contribute to oxygen consumption and suggest that the oxygen status influences the colonization success.

  4. Colonic Diseases

    MedlinePlus

    ... where your body makes and stores stool. Many disorders affect the colon's ability to work properly. Some ... abdominal cramping and other symptoms Treatment for colonic diseases varies greatly depending on the disease and its ...

  5. Vanillin differentially affects azoxymethane-injected rat colon carcinogenesis and gene expression.

    PubMed

    Ho, Ket Li; Chong, Pei Pei; Yazan, Latifah Saiful; Ismail, Maznah

    2012-12-01

    Vanillin is the substance responsible for the flavor and smell of vanilla, a widely used flavoring agent. Previous studies reported that vanillin is a good antimutagen and anticarcinogen. However, there are also some contradicting findings showing that vanillin was a comutagen and cocarcinogen. This study investigated whether vanillin is an anticarcinogen or a cocarcinogen in rats induced with azoxymethane (AOM). Rats induced with AOM will develop aberrant crypt foci (ACF). AOM-challenged rats were treated with vanillin orally and intraperitoneally at low and high concentrations and ACF density, multiplicity, and distribution were observed. The gene expression of 14 colorectal cancer-related genes was also studied. Results showed that vanillin consumed orally had no effect on ACF. However, high concentrations (300 mg/kg body weight) of vanillin administered through intraperitoneal injection could increase ACF density and ACF multiplicity. ACF were mainly found in the distal colon rather than in the mid-section and proximal colon. The expression of colorectal cancer biomarkers, protooncogenes, recombinational repair, mismatch repair, and cell cycle arrest, and tumor suppressor gene expression were also affected by vanillin. Vanillin was not cocarcinogenic when consumed orally. However, it was cocarcinogenic when being administered intraperitoneally at high concentration. Hence, the use of vanillin in food should be safe but might have cocarcinogenic potential when it is used in high concentration for therapeutic purposes.

  6. Modulators affecting the immune dialogue between human immune and colon cancer cells

    PubMed Central

    Djaldetti, Meir; Bessler, Hanna

    2014-01-01

    cells leading to a balance in cytokine production. It is conceivable that the prevalence of anti-inflammatory cytokine production by PBMC in the affected colonic mucosa will contribute to the delay, or even to halt down malignant expansion. Targeting the interplay between immune and cancer cells by mediators capable to alter cytokine secretion toward increased anti-inflammatory cytokine release by PBMC and tumor associated macrophages, may serve as an additional strategy for treatment of malignant diseases. This review will focus on the inflammatory events preceding tumorigenesis in general, and on a number of modulators capable to affect colon cancer cell-induced production of inflammatory cytokines by PBMC through alteration of the immune cross-talk between PBMC and cancer cells. PMID:24834143

  7. Gastrointestinal Mucins of Fut2-Null Mice Lack Terminal Fucosylation without Affecting Colonization by Candida albicans

    PubMed Central

    Hurd, Elizabeth A.; Holmén, Jessica M.; Hansson, Gunnar C.; Domino, Steven E.

    2006-01-01

    Post-translational modification of apomucins by the sequential action of glycosyltransferases is required to produce mature mucins. The “Secretor” gene (FUT2) encodes an α(1,2)fucosyltransferase (E.C. 2.4.1.69) that catalyzes addition of terminal α(1,2)fucose residues on mucins and other molecules in mucosal epithelium. Mutant mice containing targeted replacement of Fut2 with the bacterial reporter gene lacZ were studied to determine the affect of the loss of Fut2 on glycosylation of mucins in the gastrointestinal tract. By whole organ X-gal staining, lacZ activity is prominently expressed in the foveolar pit and chief cells of the glandular stomach, Brunner's glands of the duodenum, and goblet cells in the large intestine of Fut2-LacZ null mice. Staining with Aleuria aurantia agglutinin demonstrates loss of l-fucosylated epithelial glycans throughout the gastrointestinal tract of Fut2-LacZ null mice, however, histologic appearance of the tissues appears normal. Analysis of oligosaccharides released from insoluble colonic mucins, largely Muc2, by mass spectrometry shows complete lack of terminal fucosylation of O-linked oligosaccharides in Fut2-LacZ null mice. Precursor glycans accumulate with no evidence of compensation by other fucosyltransferases or sialyltransferases on mucin glycosylation. Since Candida albicans has been reported to adhere to intestinal mucins creating a potential reservoir associated with vaginitis, Fut2-LacZ null and wild type mice were inoculated by gastric lavage with C. albicans. We observe no difference in colonization between genotypes suggesting mucin terminal fucosylation does not significantly influence C. albicans-host interaction in the intestine, highlighting that infections caused by the same organism at different mucosal surfaces are not equal. PMID:15958416

  8. Biofilm Formation by the Fish Pathogen Flavobacterium columnare: Development and Parameters Affecting Surface Attachment

    PubMed Central

    Cai, Wenlong; De La Fuente, Leonardo

    2013-01-01

    Flavobacterium columnare is a bacterial fish pathogen that affects many freshwater species worldwide. The natural reservoir of this pathogen is unknown, but its resilience in closed aquaculture systems posits biofilm as the source of contagion for farmed fish. The objectives of this study were (i) to characterize the dynamics of biofilm formation and morphology under static and flow conditions and (ii) to evaluate the effects of temperature, pH, salinity, hardness, and carbohydrates on biofilm formation. Nineteen F. columnare strains, including representatives of all of the defined genetic groups (genomovars), were compared in this study. The structure of biofilm was characterized by light microscopy, confocal laser scanning microscopy, and scanning electron microscopy. F. columnare was able to attach to and colonize inert surfaces by producing biofilm. Surface colonization started within 6 h postinoculation, and microcolonies were observed within 24 h. Extracellular polysaccharide substances and water channels were observed in mature biofilms (24 to 48 h). A similar time course was observed when F. columnare formed biofilm in microfluidic chambers under flow conditions. The virulence potential of biofilm was confirmed by cutaneous inoculation of channel catfish fingerlings with mature biofilm. Several physicochemical parameters modulate attachment to surfaces, with the largest influence being exerted by hardness, salinity, and the presence of mannose. Maintenance of hardness and salinity values within certain ranges could prevent biofilm formation by F. columnare in aquaculture systems. PMID:23851087

  9. Regulation of the proliferation of colon cancer cells by compounds that affect glycolysis, including 3-bromopyruvate, 2-deoxyglucose and biguanides.

    PubMed

    Lea, Michael A; Qureshi, Mehreen S; Buxhoeveden, Michael; Gengel, Nicolette; Kleinschmit, Jessica; Desbordes, Charles

    2013-02-01

    In previous studies performed by our group, we observed that 2-deoxyglucose blocked the acidification of the medium used for culture of colon cancer cells caused by incubation with biguanides and it had an additive inhibitory effect on growth. In the present work, we found that 3-bromopyruvate can also prevent the lowering of pH caused by biguanide treatment. 3-Bromopyruvate inhibited colonic cancer cell proliferation, but the effect was not always additive to that of biguanides and an additive effect was more notable in combined treatment with 3-bromopyruvate and 2-deoxyglucose. The induction of alkaline phosphatase activity by butyrate was not consistently affected by combination with other agents that modified glucose metabolism. The drug combinations that were examined inhibited proliferation of wild-type and p53-null cells and affected colonic cancer lines with different growth rates.

  10. Cell surface fucosylation does not affect development of colon tumors in mice with germline Smad3 mutation

    PubMed Central

    Domino, Steven E.; Karnak, David M.; Hurd, Elizabeth A.

    2006-01-01

    Background/Aims: Neoplasia-related alterations in cell surface α(1,2)fucosylated glycans have been reported in multiple tumors including colon, pancreas, endometrium, cervix, bladder, lung, and choriocarcinoma. Spontaneous colorectal tumors from mice with a germline null mutation of transforming growth factor-β signaling gene Smad3 (Madh3) were tested for α(1,2)fucosylated glycan expression. Methods: Ulex Europaeus Agglutinin-I lectin staining, fucosyltransferase gene northern blot analysis, and a cross of mutant mice with Fut2 and Smad3 germline mutations were performed. Results: Spontaneous colorectal tumors from Smad3 (-/-) homozygous null mice were found to express α(1,2)fucosylated glycans in an abnormal pattern compared to adjacent nonneoplastic colon. Northern blot analysis of α(1,2)fucosyltransferase genes Fut1 and Fut2 revealed that Fut2, but not Fut1, steady-state mRNA levels were significantly increased in tumors relative to adjacent normal colonic mucosa. Mutant mice with a Fut2-inactivating germline mutation were crossed with Smad3 targeted mice. In Smad3 (-/-)/Fut2 (-/-) double knock-out mice, UEA-I lectin staining was eliminated from colon and colon tumors, however, the number and size of tumors present by 24 weeks of age did not vary regardless of the Fut2 genotype. Conclusions: In this model of colorectal cancer, cell surface α(1,2)fucosylation does not affect development of colon tumors. PMID:17264540

  11. Parasitoid-specific induction of plant responses to parasitized herbivores affects colonization by subsequent herbivores.

    PubMed

    Poelman, Erik H; Zheng, Si-Jun; Zhang, Zhao; Heemskerk, Nanda M; Cortesero, Anne-Marie; Dicke, Marcel

    2011-12-01

    Plants are exposed to a suite of herbivorous attackers that often arrive sequentially. Herbivory affects interactions between the host plants and subsequently attacking herbivores. Moreover, plants may respond to herbivory by emitting volatile organic compounds (VOCs) that attract carnivorous natural enemies of the herbivores. However, information borne by VOCs is ubiquitous and may attract carnivores, such as parasitoids, that differ in their effectiveness at releasing the plant from its herbivorous attackers. Furthermore, the development of parasitoids within their herbivorous hosts, attacking a given host plant, may influence the elicitation of defensive reactions in the host plant. This may, in turn, affect the behavior of subsequent herbivores attacking the host plant. Here, we show that the species identity of a parasitoid had a more significant effect on defense responses of Brassica oleracea plants than the species identity of the herbivorous hosts of the parasitoids. Consequently, B. oleracea plants that were damaged by caterpillars (Pieris spp.) parasitized by different parasitoid species varied in the degree to which diamondback moths (Plutella xylostella) selected the plants for oviposition. Attracting parasitoids in general benefitted the plants by reducing diamondback moth colonization. However, the species of parasitoid that parasitized the herbivore significantly affected the magnitude of this benefit by its species-specific effect on herbivore-plant interactions mediated by caterpillar regurgitant. Our findings show that information-mediated indirect defense may lead to unpredictable consequences for plants when considering trait-mediated effects of parasitized caterpillars on the host plant and their consequences because of community-wide responses to induced plants. PMID:22084113

  12. Parasitoid-specific induction of plant responses to parasitized herbivores affects colonization by subsequent herbivores.

    PubMed

    Poelman, Erik H; Zheng, Si-Jun; Zhang, Zhao; Heemskerk, Nanda M; Cortesero, Anne-Marie; Dicke, Marcel

    2011-12-01

    Plants are exposed to a suite of herbivorous attackers that often arrive sequentially. Herbivory affects interactions between the host plants and subsequently attacking herbivores. Moreover, plants may respond to herbivory by emitting volatile organic compounds (VOCs) that attract carnivorous natural enemies of the herbivores. However, information borne by VOCs is ubiquitous and may attract carnivores, such as parasitoids, that differ in their effectiveness at releasing the plant from its herbivorous attackers. Furthermore, the development of parasitoids within their herbivorous hosts, attacking a given host plant, may influence the elicitation of defensive reactions in the host plant. This may, in turn, affect the behavior of subsequent herbivores attacking the host plant. Here, we show that the species identity of a parasitoid had a more significant effect on defense responses of Brassica oleracea plants than the species identity of the herbivorous hosts of the parasitoids. Consequently, B. oleracea plants that were damaged by caterpillars (Pieris spp.) parasitized by different parasitoid species varied in the degree to which diamondback moths (Plutella xylostella) selected the plants for oviposition. Attracting parasitoids in general benefitted the plants by reducing diamondback moth colonization. However, the species of parasitoid that parasitized the herbivore significantly affected the magnitude of this benefit by its species-specific effect on herbivore-plant interactions mediated by caterpillar regurgitant. Our findings show that information-mediated indirect defense may lead to unpredictable consequences for plants when considering trait-mediated effects of parasitized caterpillars on the host plant and their consequences because of community-wide responses to induced plants.

  13. Mutations Affecting Hyphal Colonization and Pyoverdine Production in Pseudomonads Antagonistic toward Phytophthora parasitica.

    PubMed

    Yang, C H; Menge, J A; Cooksey, D A

    1994-02-01

    In previous studies, Pseudomonas putida 06909 and Pseudomonas fluorescens 09906 suppressed populations of Phytophthora parasitica in the citrus rhizosphere, suggesting that these bacteria may be useful in biological control of citrus root rot. In this study we investigated the mechanisms of antagonism between the bacteria and the fungus. Both bacteria colonized Phytophthora hyphae and inhibited the fungus on agar media. A hyphal column assay was developed to measure the colonization of bacteria on fungal hyphae and to enrich for colonization-deficient mutants. In this way we identified Tn5 mutants of each pseudomonad that were not able to colonize the hyphae and inhibit fungal growth in vitro. Colonization-deficient mutants were nonmotile and lacked flagella. Survival of nonmotile mutants in a citrus soil was similar to survival of a random Tn5 mutant over a 52-day period. Additional screening of random Tn5 mutants of both pseudomonads for loss of fungal inhibition in vitro yielded two distinct types of mutants. Mutants of the first type were deficient in production of pyoverdines and in inhibition of the fungus in vitro, although they still colonized fungal hyphae. Mutants of the second type lacked flagella and were not able to colonize the hyphae or inhibit fungal growth. No role was found for antibiotic production by the two bacteria in the inhibition of the fungus. Our results suggest that both hyphal colonization and pyoverdine production are important in the inhibition of Phytophthora parasitica by P. fluorescens and P. putida in vitro. PMID:16349177

  14. Global sensitivity analysis and Bayesian parameter inference for solute transport in porous media colonized by biofilms

    NASA Astrophysics Data System (ADS)

    Younes, A.; Delay, F.; Fajraoui, N.; Fahs, M.; Mara, T. A.

    2016-08-01

    The concept of dual flowing continuum is a promising approach for modeling solute transport in porous media that includes biofilm phases. The highly dispersed transit time distributions often generated by these media are taken into consideration by simply stipulating that advection-dispersion transport occurs through both the porous and the biofilm phases. Both phases are coupled but assigned with contrasting hydrodynamic properties. However, the dual flowing continuum suffers from intrinsic equifinality in the sense that the outlet solute concentration can be the result of several parameter sets of the two flowing phases. To assess the applicability of the dual flowing continuum, we investigate how the model behaves with respect to its parameters. For the purpose of this study, a Global Sensitivity Analysis (GSA) and a Statistical Calibration (SC) of model parameters are performed for two transport scenarios that differ by the strength of interaction between the flowing phases. The GSA is shown to be a valuable tool to understand how the complex system behaves. The results indicate that the rate of mass transfer between the two phases is a key parameter of the model behavior and influences the identifiability of the other parameters. For weak mass exchanges, the output concentration is mainly controlled by the velocity in the porous medium and by the porosity of both flowing phases. In the case of large mass exchanges, the kinetics of this exchange also controls the output concentration. The SC results show that transport with large mass exchange between the flowing phases is more likely affected by equifinality than transport with weak exchange. The SC also indicates that weakly sensitive parameters, such as the dispersion in each phase, can be accurately identified. Removing them from calibration procedures is not recommended because it might result in biased estimations of the highly sensitive parameters.

  15. Polysaccharide from seeds of Plantago asiatica L. affects lipid metabolism and colon microbiota of mouse.

    PubMed

    Hu, Jie-Lun; Nie, Shao-Ping; Wu, Qi-Meng; Li, Chang; Fu, Zhi-Hong; Gong, Joshua; Cui, Steve W; Xie, Ming-Yong

    2014-01-01

    Polysaccharide from the seeds of Plantago asiatica L. was given via oral administration to mice (0.4 g/kg body weight, 30 days) to observe its effects on mouse nutrient metabolism and colon microbiota. It was found the polysaccharide intake could lower the apparent absorption of lipid. Total triglyceride, cholesterol, and atherogenic index in blood serum with total lipid and cholesterol levels in liver of polysaccharide group mice were all significantly lower than those of the control group (p < 0.05). Furthermore, the effect of the polysaccharide intake on mouse colon bacterial communities was investigated. Mice from the polysaccharide group showed a higher colon bacterial diversity than the control group. Bacteroides sp., Eubacterium sp., butyrate-producing bacteria Butyrivibrio sp., and probiotics Bifidobacterium bifidum , Lactobacillus fermentum , and Lactobacillus reuteri in mouse colon were all increased after polysaccharide intake. These indicated that the intake of polysaccharide from P. asiatica L. could be beneficial for lipid metabolism and colon microbiota. PMID:24341731

  16. Laboratory measurements of parameters affecting wet deposition of methyl iodide

    SciTech Connect

    Maeck, W.J.; Honkus, R.J.; Keller, J.H.; Voilleque, P.G.

    1984-09-01

    The transfer of gaseous methyl iodide (CH/sub 3/I) to raindrops and the initial retention by vegetation of CH/sub 3/I in raindrops have been studied in a laboratory experimental program. The measured air-to-drop transfer parameters and initial retention factors both affect the wet deposition of methyl iodide onto vegetation. No large effects on the air-to-drop transfer due to methyl iodide concentration, temperature, acidity, or rain type were observed. Differences between laboratory measurements and theoretical values of the mass transfer coefficient were found. Pasture grass, lettuce, and alfalfa were used to study the initial retention of methyl iodide by vegetation. Only a small fraction of the incident CH/sub 3/I in raindrops was held by any of the three vegetation types.

  17. [Alpha-1 Antitrypsin Affects U0126-Induced Cytotoxicity in Colon Cancer Cell Line (HCT116)].

    PubMed

    Ljujic, M; Mijatovic, S; Bulatovic, M Z; Mojic, M; Maksimovic-Ivanic, D; Radojkovic, D; Topic, A

    2016-01-01

    Alpha-1-antitrypsin (AAT), an acute phase protein, is the principal circulatory anti-protease. This multifunctional protein is encoded by the SERPINA1 gene. Although AAT was recognised as a potential tumour marker, its role in cancer biology remains unknown. Given that it has been demonstrated that AAT has an anti-apoptotic property against non-malignant cells, we aimed to investigate whether AAT affects apoptosis in a colon cancer cell line (HCT116). The presence of AAT in the HCT116 cell culture antagonized cytotoxicity of blockers of MEK1/2, PI3K/Akt pathways as well as NF-κB. The dominantly recovered cell viability was observed in the co-treatment with MEK1/2 inhibitor U0126. In addition, it was revealed that AAT almost completely abolished U0126-induced apoptosis through maintenance of the autophagy process. Our study revealed for the first time that the observed cyto-protection triggered by AAT was accompanied by sustained autophagy which opposed apoptosis. These results may contribute to understanding of the role of AAT in cancer development and evaluation of efficacy of cancer therapy.

  18. Carob fibre compounds modulate parameters of cell growth differently in human HT29 colon adenocarcinoma cells than in LT97 colon adenoma cells.

    PubMed

    Klenow, S; Glei, M; Haber, B; Owen, R; Pool-Zobel, B L

    2008-04-01

    An extract of the Mediterranean carob (Ceratonia siliqua L.) pod (carob fibre extract), products formed after its fermentation by the gut flora and the major phenolic ingredient gallic acid (GA), were comparatively investigated for their influence on survival and growth parameters of colon adenocarcinoma HT29 cells and adenoma LT97 cells. Hydrogen peroxide (H2O2) formation in the cell culture media was quantified. After 1h 97+/-4 microM or 70+/-15 microM were found in HT29 medium and 6+/-1 microM or 3+/-3 microM in LT97 medium for carob fibre extract or GA, respectively. After 72 h carob fibre extract reduced survival of rapidly proliferating HT29 cells (by 76.4+/-12.9%) whereas metabolic activity and DNA-synthesis were only transiently impaired. Survival of slower growing LT97 cells was less decreased (by 21.5+/-12.9%), but there were marked effects on DNA-synthesis (reduction by 95.6+/-7%, 72 h). GA and fermented carob fibre did not have comparable effects. Thus, carob fibre extract resulted in H2O2 formation, which, however, could not explain impairment of cell growth. The differently modulated growth of human colon cell lines was more related to proliferation rates and impairment of DNA-synthesis than to H2O2 formation.

  19. Parameters Affecting Ethyl Ester Production by Saccharomyces cerevisiae during Fermentation▿

    PubMed Central

    Saerens, S. M. G.; Delvaux, F.; Verstrepen, K. J.; Van Dijck, P.; Thevelein, J. M.; Delvaux, F. R.

    2008-01-01

    Volatile esters are responsible for the fruity character of fermented beverages and thus constitute a vital group of aromatic compounds in beer and wine. Many fermentation parameters are known to affect volatile ester production. In order to obtain insight into the production of ethyl esters during fermentation, we investigated the influence of several fermentation variables. A higher level of unsaturated fatty acids in the fermentation medium resulted in a general decrease in ethyl ester production. On the other hand, a higher fermentation temperature resulted in greater ethyl octanoate and decanoate production, while a higher carbon or nitrogen content of the fermentation medium resulted in only moderate changes in ethyl ester production. Analysis of the expression of the ethyl ester biosynthesis genes EEB1 and EHT1 after addition of medium-chain fatty acid precursors suggested that the expression level is not the limiting factor for ethyl ester production, as opposed to acetate ester production. Together with the previous demonstration that provision of medium-chain fatty acids, which are the substrates for ethyl ester formation, to the fermentation medium causes a strong increase in the formation of the corresponding ethyl esters, this result further supports the hypothesis that precursor availability has an important role in ethyl ester production. We concluded that, at least in our fermentation conditions and with our yeast strain, the fatty acid precursor level rather than the activity of the biosynthetic enzymes is the major limiting factor for ethyl ester production. The expression level and activity of the fatty acid biosynthetic enzymes therefore appear to be prime targets for flavor modification by alteration of process parameters or through strain selection. PMID:17993562

  20. Parameters affecting greywater quality and its safety for reuse.

    PubMed

    Maimon, Adi; Friedler, Eran; Gross, Amit

    2014-07-15

    Reusing greywater (GW) for on-site irrigation is becoming a common practice worldwide. Alongside its benefits, GW reuse might pose health and environmental risks. The current study assesses the risks associated with on-site GW reuse and the main factors affecting them. GW from 34 households in Israel was analyzed for physicochemical parameters, Escherichia coli (as an indicator for rotavirus), Pseudomonas aeruginosa and Staphylococcus aureus. Each participating household filled out a questionnaire about their GW sources, treatment and usages. Quantitative microbial risk assessment (QMRA) was performed based on the measured microbial quality, and on exposure scenarios derived from the questionnaires and literature data. The type of treatment was found to have a significant effect on the quality of the treated GW. The average E. coli counts in GW (which exclude kitchen effluent) treated by professionally-designed system resulted in acceptable risk under all exposure scenarios while the risk from inadequately-treated GW was above the accepted level as set by the WHO. In conclusion, safe GW reuse requires a suitable and well-designed treatment system. A risk-assessment approach should be used to adjust the current regulations/guidelines and to assess the performance of GW treatment and reuse systems.

  1. Colonization and persistence of urban ant populations as revealed by joint estimation of kinship and population genetic parameters.

    PubMed

    Yamamoto, Junpei; Uchida, Kei; Takami, Yasuoki

    2013-01-01

    The decrease in biodiversity due to increasing urbanization has been well documented, but the processes of colonization and maintenance of wildlife populations in urban areas remain poorly understood. We address this issue using 462 individuals from 10 urban populations of the ant Formica japonica in Kobe City, Japan. We sampled workers regardless of colony identity, genotyped them using 6 microsatellite loci, and estimated allele frequencies and genotypes of reproductive individuals, together with other population genetic parameters, by estimating kinship structure using a likelihood method. Estimated genetic diversity and effective size of populations were not associated with environmental parameters, suggesting that populations are unaffected by urbanization. However, effective population sizes were small, and frequent population bottlenecks were detected. These results suggest that urban F. japonica populations are unstable, and the possibility of frequent extinctions and recolonizations in urban habitats. Populations were moderately differentiated without isolation by distance, suggesting a strong dispersal ability that enables colonization of urban habitats. Dispersal was male biased. Collectively, F. japonica was regarded as an urban adapter, which can colonize urban habitats by virtue of its preference for open ground and high dispersal ability but can persist in urban populations for only a short time, showing a tendency as a temporary urban inhabitant.

  2. Both population size and patch quality affect local extinctions and colonizations.

    PubMed

    Franzén, Markus; Nilsson, Sven G

    2010-01-01

    Currently, the habitat of many species is fragmented, resulting in small local populations with individuals occasionally dispersing between the remaining habitat patches. In a solitary bee metapopulation, extinction probability was related to both local bee population sizes and pollen resources measured as host plant population size. Patch size, on the other hand, had no additional predictive power. The turnover rate of local bee populations in 63 habitat patches over 4 years was high, with 72 extinction events and 31 colonization events, but the pollen plant population was stable with no extinctions or colonizations. Both pollen resources and bee populations had strong and independent effects on extinction probability, but connectivity was not of importance. Colonizations occurred more frequently within larger host plant populations. For metapopulation survival of the bee, large pollen plant populations are essential, independent of current bee population size.

  3. Alcohol and Smoking Affect Risk of Uncomplicated Colonic Diverticulosis in Japan

    PubMed Central

    Nagata, Naoyoshi; Niikura, Ryota; Shimbo, Takuro; Kishida, Yoshihiro; Sekine, Katsunori; Tanaka, Shohei; Aoki, Tomonori; Watanabe, Kazuhiro; Akiyama, Junichi; Yanase, Mikio; Itoh, Toshiyuki; Mizokami, Masashi; Uemura, Naomi

    2013-01-01

    Colonic diverticula are located predominantly on the right side in Asia and on the left side in Europe and the United States. Factors associated with uncomplicated colonic diverticulosis and its distribution pattern have been unknown. Our aims are to investigate the prevalence and risk factors for uncomplicated colonic diverticulosis. We conducted a prospective cross-sectional study in adults who underwent colonoscopy. Alcohol, alcohol related flushing, smoking, medications, and comorbidities were assessed by interview on the colonoscopy day. Alcohol consumption was categorized as nondrinker, light (1–180 g/week), moderate (181–360 g/week), and heavy (≥361 g/week). Smoking index was defined as the number of cigarettes per day multiplied by the number of smoking years and categorized as nonsmoker, <400, 400–799, and ≥800. A total of 2,164 consecutive patients were enrolled. Overall, 542 patients (25.1%) had uncomplicated colonic diverticulosis located on the right side (50%), bilaterally (29%), and on the left side (21%). Univariate analysis revealed age, male, smoking index, alcohol consumption, aspirin use, anticoagulants use, corticosteroid use, hypertension, and atherosclerotic disease as factors significantly associated with diverticulosis. Alcohol related flushing was not associated with the disease. Multivariate analysis showed increasing age (P<0.01), increasing alcohol consumption (P<0.01) and smoking (P<0.01), and atherosclerotic disease (P<0.01) as significantly associated factors. Alcohol and smoking were associated with right-sided and bilateral diverticula. In conclusion, one in four Japanese adults have colonic diverticulosis (50% right-sided). Age, alcohol consumption, and smoking were found to be significant risk factors for uncomplicated colonic diverticulosis, particularly right-sided and bilateral. PMID:24339905

  4. Folate supplementation differently affects uracil content in DNA in the mouse colon and liver

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High folate intake may increase the risk of cancer, especially in the elderly. The present study examined the effects of ageing and dietary folate on uracil misincorporation into DNA, which has a mutagenic effect, in the mouse colon and liver. Old (18 months; n 42) and young (4 months; n 42) male C5...

  5. [Colonic balantidiasis].

    PubMed

    González de Canales Simón, P; del Olmo Martínez, L; Cortejoso Hernández, A; Arranz Santos, T

    2000-03-01

    Balantidium coli is a Protozoa that is not usually pathogenic in man, although epidemics have been described in tropical areas. It mainly affects the colon and clinical presentation varies from asymptomatic forms to severe dysenteric syndromes. We present a case of endoscopically diagnosed colonic balantidiasis and review the most important characteristics of this parasite-induced disease. PMID:10804691

  6. Folic Acid Supplementation Adversely Affects Chemosensitivity of Colon Cancer Cells to 5-fluorouracil.

    PubMed

    Ishiguro, Lisa; Yang, Michael; Sohn, Kyoung-Jin; Streutker, Catherine J; Grin, Andrea; Croxford, Ruth; Kim, Young-In

    2016-07-01

    Folic acid (FA) fortification and widespread supplemental use have significantly increased folate status in North America. Furthermore, >50% of colorectal cancer patients use FA supplement. The increased folate status may interfere with cancer chemotherapy. We investigated the effect of FA supplementation on chemosensitivity of human colon cancer cells to 5-fluorouracil (5-FU) using a xenograft model. Mice harboring human HCT116 colon cancer xenografts were randomized to receive the control, or 4× or 12.5× supplemental levels of FA. Within each diet group, mice were randomized to receive 5-FU+leucovorin or saline and xenograft growth and characteristics were determined. The expression of genes involved in folate metabolism and cancer treatment was determined. FA supplementation and 5-FU significantly interacted to influence xenograft growth (P < 0.007). At the control level, 5-FU significantly inhibited the growth of the xenografts (P < 0.0001). However, at the 4× supplemental level, 5-FU-treated xenografts grew faster than untreated xenografts (P = 0.048) while at the 12.5× supplemental level, 5-FU exhibited no effect. Cell proliferation, degree of necrosis, and expression of the selected genes did not significantly differ by the supplemental levels of FA. Our data suggest that FA supplementation may be detrimental to 5-FU chemotherapy of colon cancer and pose public health concern.

  7. Colonic epithelial ion transport is not affected in patients with diverticulosis

    PubMed Central

    Osbak, Philip S; Bindslev, Niels; Poulsen, Steen S; Kaltoft, Nicolai; Tilotta, Maria C; Hansen, Mark B

    2007-01-01

    Background Colonic diverticular disease is a bothersome condition with an unresolved pathogenesis. It is unknown whether a neuroepithelial dysfunction is present. The aim of the study was two-fold; (1) to investigate colonic epithelial ion transport in patients with diverticulosis and (2) to adapt a miniaturized Modified Ussing Air-Suction (MUAS) chamber for colonic endoscopic biopsies. Methods Biopsies were obtained from the sigmoid part of the colon. 86 patients were included. All patients were referred for colonoscopy on suspicion of neoplasia and they were without pathological findings at colonoscopy (controls) except for diverticulosis in 22 (D-patients). Biopsies were mounted in MUAS chambers with an exposed area of 5 mm2. Electrical responses to various stimulators and inhibitors of ion transport were investigated together with histological examination. The MUAS chamber was easy to use and reproducible data were obtained. Results Median basal short circuit current (SCC) was 43.8 μA·cm-2 (0.8 – 199) for controls and 59.3 μA·cm-2 (3.0 – 177.2) for D-patients. Slope conductance was 77.0 mS·cm-2 (18.6 – 204.0) equal to 13 Ω·cm2 for controls and 96.6 mS·cm-2 (8.4 – 191.4) equal to 10.3 Ω·cm2 for D-patients. Stimulation with serotonin, theophylline, forskolin and carbachol induced increases in SCC in a range of 4.9 – 18.6 μA·cm-2, while inhibition with indomethacin, bumetanide, ouabain and amiloride decreased SCC in a range of 6.5 – 27.4 μA·cm-2, and all with no significant differences between controls and D-patients. Histological examinations showed intact epithelium and lamina propria before and after mounting for both types of patients. Conclusion We conclude that epithelial ion transport is not significantly altered in patients with diverticulosis and that the MUAS chamber can be adapted for studies of human colonic endoscopic biopsies. PMID:17888183

  8. Importance and sensitivity of parameters affecting the Zion Seismic Risk

    SciTech Connect

    George, L.L.; O'Connell, W.J.

    1985-06-01

    This report presents the results of a study on the importance and sensitivity of structures, systems, equipment, components and design parameters used in the Zion Seismic Risk Calculations. This study is part of the Seismic Safety Margins Research Program (SSMRP) supported by the NRC Office of Nuclear Regulatory Research. The objective of this study is to provide the NRC with results on the importance and sensitivity of parameters used to evaluate seismic risk. These results can assist the NRC in making decisions dealing with the allocation of research resources on seismic issues. This study uses marginal analysis in addition to importance and sensitivity analysis to identify subject areas (input parameter areas) for improvements that reduce risk, estimate how much the improvement dfforts reduce risk, and rank the subject areas for improvements. Importance analysis identifies the systems, components, and parameters that are important to risk. Sensitivity analysis estimates the change in risk per unit improvement. Marginal analysis indicates the reduction in risk or uncertainty for improvement effort made in each subject area. The results described in this study were generated using the SEISIM (Systematic Evaluation of Important Safety Improvement Measures) and CHAIN computer codes. Part 1 of the SEISIM computer code generated the failure probabilities and risk values. Part 2 of SEISIM, along with the CHAIN computer code, generated the importance and sensitivity measures.

  9. Can a Short Term of Repeated Ejaculations Affect Seminal Parameters?

    PubMed Central

    Mayorga-Torres, Jose Manuel; Agarwal, Ashok; Roychoudhury, Shubhadeep; Cadavid, Angela; Cardona-Maya, Walter Dario

    2016-01-01

    Background: The aim of the study was to assess the effect of four repeated ejaculations on the same day at two-hour intervals on conventional and functional semen parameters. Methods: Three healthy men (32±3.6 years) donated the first semen samples after 3–4 days of sexual abstinence followed by three subsequent samples on the same day at two-hour interval each. Semen samples were processed and analyzed according to the World Health Organization (WHO) 2010 guidelines. Furthermore, intracellular reactive oxygen (ROS) production, sperm DNA fragmentation and mitochondrial function were evaluated by flow cytometry. Results: An overall decreasing trend was noted in the conventional semen parameters at second, third and fourth evaluations after two hours of abstinence in comparison to first evaluation after 3–4 days of abstinence. The statistical comparison of the conventional semen parameters at fourth evaluation after 2 hr of abstinence revealed significant reduction (p<0.05) in the parameters of concentration, total sperm count and total motile sperm count at fourth evaluation. The functional parameter of intracellular ROS production showed a decreasing trend with each subsequent evaluation, the difference being significant (p<0.05) at fourth evaluation in comparison to first evaluation. An increasing trend was noted for DNA fragmentation index (DFI), although it remained within acceptable levels (<29%). The ΔΨm high permatozoa and the integrity of the plasma membrane remained stable throughout the evaluations. Conclusion: The findings of the present study indicate the potential use of additional semen samples with repeated ejaculations at short abstinence times in assisted reproduction procedures particularly from severe oligospermic men. PMID:27478772

  10. How Does Calibration Timing and Seasonality Affect Item Parameter Estimates?

    ERIC Educational Resources Information Center

    Wyse, Adam E.; Babcock, Ben

    2016-01-01

    Continuously administered examination programs, particularly credentialing programs that require graduation from educational programs, often experience seasonality where distributions of examine ability may differ over time. Such seasonality may affect the quality of important statistical processes, such as item response theory (IRT) item…

  11. Carcinogen and dietary lipid regulate ras expression and localization in rat colon without affecting farnesylation kinetics.

    PubMed

    Davidson, L A; Lupton, J R; Jiang, Y H; Chapkin, R S

    1999-05-01

    Epidemiological and experimental data suggest that dietary fiber and fat are major determinants of colorectal cancer. However, the mechanisms by which these dietary constituents alter the incidence of colon cancer have not been elucidated. Evidence indicates that dominant gain-of-function mutations short-circuit protooncogenes and contribute to the pathogenesis of cancer. Therefore, we began to dissect the mechanisms whereby dietary fat and fiber, fed during the initiation, promotion and progression stages of colon tumorigenesis, regulate ras p21 localization, expression and mutation frequency. Male Sprague-Dawley rats (140) were provided with corn oil or fish oil and pectin or cellulose plus or minus the carcinogen azoxymethane (AOM) in a 2 x 2 x 2 factorial design and killed after 34 weeks. We have previously shown adenocarcinoma incidence in these animals to be 70.3% (52/74) for corn oil + AOM and 56.1% (37/66) for fish oil + AOM (P < 0.05). Total ras expression as well as ras membrane:cytosol ratio was 4- to 6-fold higher in colon tumors than in mucosa from AOM- or saline-injected rats. Expression of ras in the mucosal membrane fraction was 13% higher for animals fed corn oil compared with fish oil feeding (P < 0.05), which is noteworthy since ras must be localized at the plasma membrane to function. The elevated ras membrane:cytosol ratio in tumors was not due to increased farnesyl protein transferase activity or prenylation state, as nearly all detectable ras was in the prenylated form. Phosphorylated p42 and p44 mitogen activated protein kinase (ERK) expression was two-fold higher in tumor extracts compared with uninvolved mucosa from AOM- and saline-injected rats (P < 0.05). The frequency of K-ras mutations was not significantly different between the various groups, but there was a trend toward a greater incidence of mutations in tumors from corn oil fed rats (85%) compared with fish oil fed rats (58%). Our results indicate that the carcinogen

  12. Proteome analysis of the macroscopically affected colonic mucosa of Crohn’s disease and intestinal tuberculosis

    PubMed Central

    Rukmangadachar, Lokesh A.; Makharia, Govind K.; Mishra, Asha; Das, Prasenjit; Hariprasad, Gururao; Srinivasan, Alagiri; Gupta, Siddhartha Datta; Ahuja, Vineet; Acharya, Subrat K.

    2016-01-01

    Differentiation between intestinal tuberculosis (ITB) and Crohn’s disease (CD) is challenging in geographical regions where both these diseases are prevalent. There is a need of biomarkers for differentiation between these two disorders. Colonic biopsies from inflamed mucosa of treatment-naive patients with ITB, CD and controls were used for analysis. Protein extracted from biopsies was digested with trypsin and resulting peptides were labeled with iTRAQ reagents. The peptides were subsequently analyzed using LC-MS/MS for identification and quantification. Gene ontology annotation for proteins was analyzed in PANTHER. Validation experiments were done for six differentially expressed proteins using immunohistochemistry. 533 proteins were identified and 241 proteins were quantified from 5 sets of iTRAQ experiments. While 63 were differentially expressed in colonic mucosa of patients with CD and ITB in at least one set of iTRAQ experiment, 11 proteins were differentially expressed in more than one set of experiments. Six proteins used for validation using immunohistochemistry in a larger cohort of patients; none of them however was differentially expressed in patients with ITB and CD. There are differentially expressed proteins in tissue proteome of CD and ITB. Further experiments are required using a larger cohort of homogeneous tissue samples. PMID:26988818

  13. Methanolic extracts of bitter melon inhibit colon cancer stem cells by affecting energy homeostasis and autophagy.

    PubMed

    Kwatra, Deep; Subramaniam, Dharmalingam; Ramamoorthy, Prabhu; Standing, David; Moran, Elizabeth; Velayutham, Ravichandiran; Mitra, Ashim; Umar, Shahid; Anant, Shrikant

    2013-01-01

    Bitter melon fruit is recommended in ancient Indian and Chinese medicine for prevention/treatment of diabetes. However its effects on cancer progression are not well understood. Here, we have determined the efficacy of methanolic extracts of bitter melon on colon cancer stem and progenitor cells. Both, whole fruit (BMW) and skin (BMSk) extracts showed significant inhibition of cell proliferation and colony formation, with BMW showing greater efficacy. In addition, the cells were arrested at the S phase of cell cycle. Moreover, BMW induced the cleavage of LC3B but not caspase 3/7, suggesting that the cells were undergoing autophagy and not apoptosis. Further confirmation of autophagy was obtained when western blots showed reduced Bcl-2 and increased Beclin-1, Atg 7 and 12 upon BMW treatment. BMW reduced cellular ATP levels coupled with activation of AMP activated protein kinase; on the other hand, exogenous additions of ATP lead to revival of cell proliferation. Finally, BMW treatment results in a dose-dependent reduction in the number and size of colonospheres. The extracts also decreased the expression of DCLK1 and Lgr5, markers of quiescent, and activated stem cells. Taken together, these results suggest that the extracts of bitter melon can be an effective preventive/therapeutic agent for colon cancer. PMID:23533514

  14. Does bleeding affect fetal Doppler parameters during genetic amniocentesis?

    PubMed Central

    İskender, Cantekin; Tarım, Ebru; Çok, Tayfun; Kalaycı, Hakan; Parlakgümüş, Ayşe; Yalçınkaya, Cem

    2014-01-01

    Objective The aim of this study was to investigate the relationship between fetal Doppler parameters and bleeding at insertion points during amniocentesis. Material and Methods This prospective study was conducted between July 2010 and February 2011. A total of 215 amniocentesis procedures were performed during this period. Five patients with Down syndrome were excluded from the study. The remaining 210 patients were divided into Group 1 (bleeding at insertion site) and Group 2 as a control group. One needle type was used for all patients. Umbilical artery resistance index (UARI), umbilical artery pulsatility index (UAPI), middle cerebral artery resistance index (MCARI), middle cerebral artery pulsatility index (MCA PI), and middle cerebral artery peak systolic velocity (MCAPSV) were measured immediately and before and after amniocentesis. Results Bleeding at the insertion point during amniocentesis did not significantly change the UARI (34% increase for Group 1 and 46.5% increase for Group 2, p=0.238), the MCARI (52% increase for Group 1 and 45% increase for Group 2, p=0.622), or the MCAPSV (37% increase for Group 1 and 49% increase for Group 2, p=0.199). UARI, MCARI, MCA PI, and MCAPSV were not significantly altered following amniocentesis in Groups 1 and 2. There was a significant increase in UAPI following amniocentesis only in Group 2. Conclusion Bleeding during genetic amniocentesis did not change umbilical artery and middle cerebral artery Doppler parameters. PMID:24976776

  15. MDM2 promoter SNP55 (rs2870820) affects risk of colon cancer but not breast-, lung-, or prostate cancer.

    PubMed

    Helwa, Reham; Gansmo, Liv B; Romundstad, Pål; Hveem, Kristian; Vatten, Lars; Ryan, Bríd M; Harris, Curtis C; Lønning, Per E; Knappskog, Stian

    2016-01-01

    Two functional SNPs (SNP285G > C; rs117039649 and SNP309T > G; rs2279744) have previously been reported to modulate Sp1 transcription factor binding to the promoter of the proto-oncogene MDM2, and to influence cancer risk. Recently, a third SNP (SNP55C > T; rs2870820) was also reported to affect Sp1 binding and MDM2 transcription. In this large population based case-control study, we genotyped MDM2 SNP55 in 10,779 Caucasian individuals, previously genotyped for SNP309 and SNP285, including cases of colon (n = 1,524), lung (n = 1,323), breast (n = 1,709) and prostate cancer (n = 2,488) and 3,735 non-cancer controls, as well as 299 healthy African-Americans. Applying the dominant model, we found an elevated risk of colon cancer among individuals harbouring SNP55TT/CT genotypes compared to the SNP55CC genotype (OR = 1.15; 95% CI = 1.01-1.30). The risk was found to be highest for left-sided colon cancer (OR = 1.21; 95% CI = 1.00-1.45) and among females (OR = 1.32; 95% CI = 1.01-1.74). Assessing combined genotypes, we found the highest risk of colon cancer among individuals harbouring the SNP55TT or CT together with the SNP309TG genotype (OR = 1.21; 95% CI = 1.00-1.46). Supporting the conclusions from the risk estimates, we found colon cancer cases carrying the SNP55TT/CT genotypes to be diagnosed at younger age as compared to SNP55CC (p = 0.053), in particular among patients carrying the SNP309TG/TT genotypes (p = 0.009). PMID:27624283

  16. MDM2 promoter SNP55 (rs2870820) affects risk of colon cancer but not breast-, lung-, or prostate cancer

    PubMed Central

    Helwa, Reham; Gansmo, Liv B.; Romundstad, Pål; Hveem, Kristian; Vatten, Lars; Ryan, Bríd M.; Harris, Curtis C.; Lønning, Per E.; Knappskog, Stian

    2016-01-01

    Two functional SNPs (SNP285G > C; rs117039649 and SNP309T > G; rs2279744) have previously been reported to modulate Sp1 transcription factor binding to the promoter of the proto-oncogene MDM2, and to influence cancer risk. Recently, a third SNP (SNP55C > T; rs2870820) was also reported to affect Sp1 binding and MDM2 transcription. In this large population based case-control study, we genotyped MDM2 SNP55 in 10,779 Caucasian individuals, previously genotyped for SNP309 and SNP285, including cases of colon (n = 1,524), lung (n = 1,323), breast (n = 1,709) and prostate cancer (n = 2,488) and 3,735 non-cancer controls, as well as 299 healthy African-Americans. Applying the dominant model, we found an elevated risk of colon cancer among individuals harbouring SNP55TT/CT genotypes compared to the SNP55CC genotype (OR = 1.15; 95% CI = 1.01–1.30). The risk was found to be highest for left-sided colon cancer (OR = 1.21; 95% CI = 1.00–1.45) and among females (OR = 1.32; 95% CI = 1.01–1.74). Assessing combined genotypes, we found the highest risk of colon cancer among individuals harbouring the SNP55TT or CT together with the SNP309TG genotype (OR = 1.21; 95% CI = 1.00–1.46). Supporting the conclusions from the risk estimates, we found colon cancer cases carrying the SNP55TT/CT genotypes to be diagnosed at younger age as compared to SNP55CC (p = 0.053), in particular among patients carrying the SNP309TG/TT genotypes (p = 0.009). PMID:27624283

  17. Parameters affecting of Akkuyu's safety assessment for severe core damages

    NASA Astrophysics Data System (ADS)

    Kavun, Yusuf; Karasulu, Muzaffer

    2015-07-01

    We have looked at all past core meltdowns (Three Mile Island, Chernobyl and Fukushima incidents) and postulated the fourth one might be taking place in the future most probably in a newly built reactors anywhere of the earth in any type of NPP. The probability of this observation is high considering the nature of the machine and human interaction. Operation experience is a very significant parameter as well as the safety culture of the host nation. The concerns is not just a lack of experience with industry with the new comers, but also the infrastructure and established institutions who will be dealing with the Emergencies. Lack of trained and educated Emergency Response Organizations (ERO) is a major concern. The culture on simple fire drills even makes the difference when a severe condition occurs in the industry. The study assumes the fourth event will be taking place at the Akkuyu NGS and works backwards as required by the "what went wrong " scenarios and comes up with interesting results. The differences studied in depth to determine the impact to the severe accidents. The all four design have now core catchers. We have looked at the operator errors'like in TMI); Operator errors combined with design deficiencies(like in Chernobyl) and natural disasters( like in Fukushima) and found operator errors to be more probable event on the Akkuyu's postulated next incident. With respect to experiences of the operators we do not have any data except for long and successful operating history of the Soviet design reactors up until the Chernobyl incident. Since the Akkuyu will be built, own and operated by the Russians we have found no alarming concerns at the moment. At the moment, there is no body be able to operate those units in Turkey. Turkey is planning to build the required manpower during the transition period. The resolution of the observed parameters lies to work and educate, train of the host nation and exercise together.

  18. Does Methylphenidate Affect Cystometric Parameters in Spontaneously Hypertensive Rats?

    PubMed Central

    Kim, Khae Hawn; Jung, Ha Bum; Choi, Don Kyoung; Park, Geun Ho; Cho, Sung Tae

    2015-01-01

    Purpose: Methylphenidate (MPH) is one of the most commonly prescribed psychostimulants for attention deficit hyperactivity disorder (ADHD). However, there is limited research on its effects on lower urinary tract function. This study investigated changes in cystometric parameters after intragastric administration of MPH in conscious spontaneously hypertensive rats (SHRs), an animal model of ADHD. Methods: Fourteen- to 16-week-old male SHRs (n=10), weighing between 280 and 315 g, were used. Three micturition cycles were recorded before administering MPH. One hour after each intragastric MPH injection, three cycles of cystometrogram were obtained in the awake condition. Various cystometric parameters were evaluated, including basal pressure (BP), maximal pressure (MP), threshold pressure (TP), bladder capacity (BC), micturition volume (MV), micturition interval (MI), and residual volume (RV). The data were analyzed using paired Student t-tests. Results: Five SHRs were each administered a dose of 3-mg/kg MPH, and the other five received a dose of 6-mg/kg MPH. BP and MP increased significantly in the rats that received the 3-mg/kg MPH injection, but not in those that received the 6-mg/kg injection. BC, MV, and MI significantly increased in the rats that received the 6-mg/kg MPH injection, but not in those that received the 3-mg/kg injection. There were no significant changes in TP after either injection. Conclusions: Significant increases in BC, MV, and MI after the 6-mg/kg MPH injection suggest that the peripheral and the central nervous systems may play important roles in bladder function in those receiving MPH for ADHD. PMID:26126435

  19. Does Wheat Genetically Modified for Disease Resistance Affect Root-Colonizing Pseudomonads and Arbuscular Mycorrhizal Fungi?

    PubMed Central

    Foetzki, Andrea; Luginbühl, Carolin; Winzeler, Michael; Kneubühler, Yvan; Matasci, Caterina; Mascher-Frutschi, Fabio; Kalinina, Olena; Boller, Thomas; Keel, Christoph; Maurhofer, Monika

    2013-01-01

    This study aimed to evaluate the impact of genetically modified (GM) wheat with introduced pm3b mildew resistance transgene, on two types of root-colonizing microorganisms, namely pseudomonads and arbuscular mycorrhizal fungi (AMF). Our investigations were carried out in field trials over three field seasons and at two locations. Serial dilution in selective King's B medium and microscopy were used to assess the abundance of cultivable pseudomonads and AMF, respectively. We developed a denaturing gradient gel electrophoresis (DGGE) method to characterize the diversity of the pqqC gene, which is involved in Pseudomonas phosphate solubilization. A major result was that in the first field season Pseudomonas abundances and diversity on roots of GM pm3b lines, but also on non-GM sister lines were different from those of the parental lines and conventional wheat cultivars. This indicates a strong effect of the procedures by which these plants were created, as GM and sister lines were generated via tissue cultures and propagated in the greenhouse. Moreover, Pseudomonas population sizes and DGGE profiles varied considerably between individual GM lines with different genomic locations of the pm3b transgene. At individual time points, differences in Pseudomonas and AMF accumulation between GM and control lines were detected, but they were not consistent and much less pronounced than differences detected between young and old plants, different conventional wheat cultivars or at different locations and field seasons. Thus, we conclude that impacts of GM wheat on plant-beneficial root-colonizing microorganisms are minor and not of ecological importance. The cultivation-independent pqqC-DGGE approach proved to be a useful tool for monitoring the dynamics of Pseudomonas populations in a wheat field and even sensitive enough for detecting population responses to altered plant physiology. PMID:23372672

  20. Determination of the key parameters affecting historic communications satellite trends

    NASA Technical Reports Server (NTRS)

    Namkoong, D.

    1984-01-01

    Data representing 13 series of commercial communications satellites procured between 1968 and 1982 were analyzed to determine the factors that have contributed to the general reduction over time of the per circuit cost of communications satellites. The model by which the data were analyzed was derived from a general telecommunications application and modified to be more directly applicable for communications satellites. In this model satellite mass, bandwidth-years, and technological change were the variable parameters. A linear, least squares, multiple regression routine was used to obtain the measure of significance of the model. Correlation was measured by coefficient of determination (R super 2) and t-statistic. The results showed that no correlation could be established with satellite mass. Bandwidth-year however, did show a significant correlation. Technological change in the bandwidth-year case was a significant factor in the model. This analysis and the conclusions derived are based on mature technologies, i.e., satellite designs that are evolutions of earlier designs rather than the first of a new generation. The findings, therefore, are appropriate to future satellites only if they are a continuation of design evolution.

  1. Parameters affecting pharyngeal response to genioglossus stimulation in sleep apnoea.

    PubMed

    Dotan, Y; Golibroda, T; Oliven, R; Netzer, A; Gaitini, L; Toubi, A; Oliven, A

    2011-08-01

    Chronic stimulation of the hypoglossus nerve may provide a new treatment modality for obstructive sleep apnoea (OSA). In previous studies we observed large differences in response to stimulation of the genioglossus (GG). We hypothesised that both individual patient characteristics and the area of the GG stimulated are responsible for these differences. In the present study, we compared the response to GG electrical stimulation at the anterior area (GGa-ES), which activates the whole GG and the posterior area (GGp-ES), which activates preferentially the longitudinal fibres. Studies were performed in 14 propofol-sedated OSA patients. The parameters evaluated included cephalometry, pressure-flow relationship and pharyngeal shape and compliance assessed by pharyngoscopy. Compared with GGa-ES, GGp-ES resulted in significantly larger decreases in the critical value of end-expiratory pressure (P(crit)) (from 3.8 ± 2.2 to 2.9 ± 3.3 and -2.0 ± 3.9 cmH(2)O, respectively (p<0.001)). Both tongue size and velopharyngeal shape (anteroposterior to lateral ratio) correlated significantly with the decrease in P(crit) during GGp-ES (R = 0.53 and -0.66, respectively; p<0.05). In the patients with the larger tongue size (n = 7), the decrease in P(crit) reached 8.0 ± 2.2 cmH(2)O during GGp-ES. We conclude that directing stimulation to longitudinal fibres of the GG improves the flow-mechanical effect. In addition, patients with large tongues and narrow pharynx tend to respond better to GGp-ES.

  2. Drug membrane transporters and CYP3A4 are affected by hypericin, hyperforin or aristoforin in colon adenocarcinoma cells.

    PubMed

    Šemeláková, M; Jendželovský, R; Fedoročko, P

    2016-07-01

    Our previous results have shown that the combination of hypericin-mediated photodynamic therapy (HY-PDT) at sub-optimal dose with hyperforin (HP) (compounds of Hypericum sp.), or its stable derivative aristoforin (AR) stimulates generation of reactive oxygen species (ROS) leading to antitumour activity. This enhanced oxidative stress evoked the need for an explanation for HY accumulation in colon cancer cells pretreated with HP or AR. Generally, the therapeutic efficacy of chemotherapeutics is limited by drug resistance related to the overexpression of drug efflux transporters in tumour cells. Therefore, the impact of non-activated hypericin (HY), HY-PDT, HP and AR on cell membrane transporter systems (Multidrug resistance-associated protein 1-MRP1/ABCC1, Multidrug resistance-associated protein 2-MRP2/ABCC2, Breast cancer resistance protein - BCRP/ABCG2, P-glycoprotein-P-gp/ABCC1) and cytochrome P450 3A4 (CYP3A4) was evaluated. The different effects of the three compounds on their expression, protein level and activity was determined under specific PDT light (T0+, T6+) or dark conditions (T0- T6-). We found that HP or AR treatment affected the protein levels of MRP2 and P-gp, whereas HP decreased MRP2 and P-gp expression mostly in the T0+ and T6+ conditions, while AR decreased MRP2 in T0- and T6+. Moreover, HY-PDT treatment induced the expression of MRP1. Our data demonstrate that HP or AR treatment in light or dark PDT conditions had an inhibitory effect on the activity of individual membrane transport proteins and significantly decreased CYP3A4 activity in HT-29 cells. We found that HP or AR significantly affected intracellular accumulation of HY in HT-29 colon adenocarcinoma cells. These results suggest that HY, HP and AR might affect the efficiency of anti-cancer drugs, through interaction with membrane transporters and CYP3A4. PMID:27261575

  3. Microbial colonization affects the efficiency of photovoltaic panels in a tropical environment.

    PubMed

    Shirakawa, Marcia A; Zilles, Roberto; Mocelin, Andre; Gaylarde, Christine C; Gorbushina, Anna; Heidrich, Gabriele; Giudice, Mauro C; Del Negro, Gilda M B; John, Vanderley M

    2015-07-01

    Sub-aerial biofilm (SAB) development on solar panels was studied in São Paulo. After 6, 12 and 18 months' exposure, photovoltaic panels were covered by increasing proportions of organic matter (42%, 53% and 58%, respectively). Fungi were an important component of these biofilms; very few phototrophs were found. Major microorganisms detected were melanised meristematic ascomycetes and pigmented bacterial genera Arthrobacter and Tetracoccus. While diverse algae, cyanobacteria and bacteria were identified in biofilms at 6 and 12 months, diversity at a later stage was reduced to that typical for SAB: the only fungal group detected in 18 month biofilm was the meristematic Dothideomycetes and the only phototrophs Ulothrix and Chlorella. Photovoltaic modules showed significant power reductions after 6, 12 (both 7%) and 18 (11%) months. The lack of difference in power reduction between 6 and 12 months reflects the dual nature of soiling, which can result from the deposition of particulates as well as from SAB fouling. Although 12-month old SAB demonstrated an almost 10-fold increase in fungal colonization and a higher organic content, the larger non-microbial particles (above 10 μm), which were important for efficiency reduction of lightly-biofilmed panels, were removed by high rainfall just before the 12-month sampling.

  4. Microbial colonization affects the efficiency of photovoltaic panels in a tropical environment.

    PubMed

    Shirakawa, Marcia A; Zilles, Roberto; Mocelin, Andre; Gaylarde, Christine C; Gorbushina, Anna; Heidrich, Gabriele; Giudice, Mauro C; Del Negro, Gilda M B; John, Vanderley M

    2015-07-01

    Sub-aerial biofilm (SAB) development on solar panels was studied in São Paulo. After 6, 12 and 18 months' exposure, photovoltaic panels were covered by increasing proportions of organic matter (42%, 53% and 58%, respectively). Fungi were an important component of these biofilms; very few phototrophs were found. Major microorganisms detected were melanised meristematic ascomycetes and pigmented bacterial genera Arthrobacter and Tetracoccus. While diverse algae, cyanobacteria and bacteria were identified in biofilms at 6 and 12 months, diversity at a later stage was reduced to that typical for SAB: the only fungal group detected in 18 month biofilm was the meristematic Dothideomycetes and the only phototrophs Ulothrix and Chlorella. Photovoltaic modules showed significant power reductions after 6, 12 (both 7%) and 18 (11%) months. The lack of difference in power reduction between 6 and 12 months reflects the dual nature of soiling, which can result from the deposition of particulates as well as from SAB fouling. Although 12-month old SAB demonstrated an almost 10-fold increase in fungal colonization and a higher organic content, the larger non-microbial particles (above 10 μm), which were important for efficiency reduction of lightly-biofilmed panels, were removed by high rainfall just before the 12-month sampling. PMID:25909440

  5. Physcomitrella patens mutants affected on heat dissipation clarify the evolution of photoprotection mechanisms upon land colonization.

    PubMed

    Alboresi, Alessandro; Gerotto, Caterina; Giacometti, Giorgio M; Bassi, Roberto; Morosinotto, Tomas

    2010-06-15

    Light is the source of energy for photosynthetic organisms; when in excess, however, it also drives the formation of reactive oxygen species and, consequently, photoinhibition. Plants and algae have evolved mechanisms to regulate light harvesting efficiency in response to variable light intensity so as to avoid oxidative damage. Nonphotochemical quenching (NPQ) consists of the rapid dissipation of excess excitation energy as heat. Although widespread among oxygenic photosynthetic organisms, NPQ shows important differences in its machinery. In land plants, such as Arabidopsis thaliana, NPQ depends on the presence of PSBS, whereas in the green alga Chlamydomonas reinhardtii it requires a different protein called LHCSR. In this work, we show that both proteins are present in the moss Physcomitrella patens. By generating KO mutants lacking PSBS and/or LHCSR, we also demonstrate that both gene products are active in NPQ. Plants lacking both proteins are more susceptible to high light stress than WT, implying that they are active in photoprotection. These results suggest that NPQ is a fundamental mechanism for survival in excess light and that upon land colonization, photosynthetic organisms evolved a unique mechanism for excess energy dissipation before losing the ancestral one found in algae.

  6. Phenotypic differentiation does not affect tumorigenicity of primary human colon cancer initiating cells.

    PubMed

    Dubash, Taronish D; Hoffmann, Christopher M; Oppel, Felix; Giessler, Klara M; Weber, Sarah; Dieter, Sebastian M; Hüllein, Jennifer; Zenz, Thorsten; Herbst, Friederike; Scholl, Claudia; Weichert, Wilko; Werft, Wiebke; Benner, Axel; Schmidt, Manfred; Schneider, Martin; Glimm, Hanno; Ball, Claudia R

    2016-02-28

    Within primary colorectal cancer (CRC) a subfraction of all tumor-initiating cells (TIC) drives long-term progression in serial xenotransplantation. It has been postulated that efficient maintenance of TIC activity in vitro requires serum-free spheroid culture conditions that support a stem-like state of CRC cells. To address whether tumorigenicity is indeed tightly linked to such a stem-like state in spheroids, we transferred TIC-enriched spheroid cultures to serum-containing adherent conditions that should favor their differentiation. Under these conditions, primary CRC cells did no longer grow as spheroids but formed an adherent cell layer, up-regulated colon epithelial differentiation markers, and down-regulated TIC-associated markers. Strikingly, upon xenotransplantation cells cultured under either condition equally efficient formed serially transplantable tumors. Clonal analyses of individual lentivirally marked TIC clones cultured under either culture condition revealed no systematic differences in contributing clone numbers, indicating that phenotypic differentiation does not select for few individual clones adapted to unfavorable culture conditions. Our results reveal that CRC TIC can be propagated under conditions previously thought to induce their elimination. This phenotypic plasticity allows addressing primary human CRC TIC properties in experimental settings based on adherent cell growth.

  7. Affective state influences perception by affecting decision parameters underlying bias and sensitivity.

    PubMed

    Lynn, Spencer K; Zhang, Xuan; Barrett, Lisa Feldman

    2012-08-01

    Studies of the effect of affect on perception often show consistent directional effects of a person's affective state on perception. Unpleasant emotions have been associated with a "locally focused" style of stimulus evaluation, and positive emotions with a "globally focused" style. Typically, however, studies of affect and perception have not been conducted under the conditions of perceptual uncertainty and behavioral risk inherent to perceptual judgments outside the laboratory. We investigated the influence of perceivers' experienced affect (valence and arousal) on the utility of social threat perception by combining signal detection theory and behavioral economics. We compared 3 perceptual decision environments that systematically differed with respect to factors that underlie uncertainty and risk: the base rate of threat, the costs of incorrect identification threat, and the perceptual similarity of threats and nonthreats. We found that no single affective state yielded the best performance on the threat perception task across the 3 environments. Unpleasant valence promoted calibration of response bias to base rate and costs, high arousal promoted calibration of perceptual sensitivity to perceptual similarity, and low arousal was associated with an optimal adjustment of bias to sensitivity. However, the strength of these associations was conditional upon the difficulty of attaining optimal bias and high sensitivity, such that the effect of the perceiver's affective state on perception differed with the cause and/or level of uncertainty and risk.

  8. The Relationship between Serum Oxalic Acid, Central Hemodynamic Parameters and Colonization by Oxalobacter formigenes in Hemodialysis Patients

    PubMed Central

    Gulhan, Baris; Turkmen, Kultigin; Aydin, Merve; Gunay, Murat; Cıkman, Aytekin; Kara, Murat

    2015-01-01

    Background/Objective Elevated pulse wave velocity (PWV) and central aortic blood pressures are independent predictors of increased cardiovascular morbidity and mortality in hemodialysis (HD) patients. Oxalic acid is a uremic retention molecule that is extensively studied in the pathogenesis of calcium oxalate stones. Oxalobacter formigenes, a member of the colon microbiota, has important roles in oxalate homeostasis. Data regarding the colonization by and the exact role of O. formigenes in the pathogenesis of oxalic acid metabolism in HD patients are scant. Hence, we aimed to determine the relationship between fecal O. formigenes colonization, serum oxalic acid and hemodynamic parameters in HD patients with regard to the colo-reno-cardiac axis. Methods Fifty HD patients were enrolled in this study. PWV and central aortic systolic (cASBP) and diastolic blood pressures (cADBP) were measured with a Mobil-O-Graph (I.E.M. GmbH, Stolberg, Germany). Serum oxalic acid levels were assessed by ELISA, and fecal O. formigenes DNA levels were isolated and measured by real-time PCR. Results Isolation of fecal O. formigenes was found in only 2 HD patients. One of them had 113,609 copies/ml, the other one had 1,056 copies/ml. Serum oxalic acid levels were found to be positively correlated with PWV (r = 0.29, p = 0.03), cASBP (r = 0.33, p = 0.001) and cADBP (r = 0.42, p = 0.002) and negatively correlated with LDL (r = −0.30, p = 0.03). In multivariate linear regression analysis, PWV was independently predicted by oxalic acid, glucose and triglyceride. Conclusions This is the first study that demonstrates the absence of O. formigenes as well as a relation between serum oxalic acid and cASBP, cADBP and PWV in HD patients. Replacement of O. formigenes with pre- and probiotics might decrease serum oxalic acid levels and improve cardiovascular outcomes in HD patients. PMID:26195968

  9. Colon cancer metastasis in mouse liver is not affected by hypercoagulability due to Factor V Leiden mutation

    PubMed Central

    Klerk, CPW; Smorenburg, SM; Spek, CA; Van Noorden, CJF

    2007-01-01

    Abstract Clinical trials have shown life-prolonging effects of antithrombotics in cancer patients, but the molecular mechanisms remain unknown due to the multitude of their effects. We investigated in a mouse model whether one of the targets of antithrombotic therapy, fibrin deposition, stimulates tumour development. Fibrin may provide either protection of cancer cells in the circulation against mechanical stress and the immune system, or form a matrix for tumours and/or angiogenesis in tumours to develop. Mice homozygous for Factor V Leiden (FVL), a mutation in one of the coagulation factors that facilitates fibrin formation, were used to investigate whether hypercoagulability affects tumour development in an experimental metastasis model. Liver metastases of colon cancer were induced in mice with the FVL mutation and wild-type littermates. At day 21, number and size of tumours at the liver surface, fibrin/fibrinogen distribution, vessel density and the presence of newly formed vessels in tumours were analysed. Number and size of tumours did not differ between mice with and without the FVL mutation. Fibrin/fibrinogen was found in the cytoplasm of hepatocytes and cancer cells, in blood vessels in liver and tumour tissue and diffusely distributed outside vessels in tumours, indicating leaky vessels. Vessel density and angiogenesis varied widely between tumours, but a pre-dominance for vessel-rich or vessel-poor tumours or vessel formation could not be found in either genotype. In conclusion, the FVL mutation has no effect on the development of secondary tumours of colon cancer in livers of mice. Fibrin deposition and thus inhibition of fibrin formation by anticoagulants do not seem to affect tumour development in this model. PMID:17635646

  10. Glucocorticoids and the non-steroidal selective glucocorticoid receptor modulator, compound A, differentially affect colon cancer-derived myofibroblasts.

    PubMed

    Drebert, Zuzanna; Bracke, Marc; Beck, Ilse M

    2015-05-01

    The glucocorticoid receptor functions as a ligand-dependent transcription factor that positively or negatively regulates the transcription of various specific target genes. Not only steroidal glucocorticoids can bind and activate the glucocorticoid receptor, but also the intensively examined non-steroidal selective glucocorticoid receptor modulators can do so, albeit with a select effector profile skewed to glucocorticoid receptor transrepression. Glucocorticoids are widely used to treat inflammatory afflictions, but also as anti-cancer therapies or adjuvants thereof. As the impact of glucocorticoids and selective glucocorticoid receptor modulators has scarcely been researched in this setting, we focused on colon cancer and its stromal environment, in particular the stromal myofibroblasts, which are known to influence cancer cells via paracrine signaling. In these myofibroblasts, the glucocorticoid dexamethasone is able to drive the glucocorticoid receptor into the nucleus and thus negatively regulates the expression of particular pro-inflammatory genes in TNFα-stimulated cells. The selective glucocorticoid receptor modulator compound A has an impaired ability to translocate GR, presumably underpinning its modest anti-inflammatory properties in these cells. Only dexamethasone, and not compound A, can upregulate the glucocorticoid receptor transactivation-dependent GILZ expression. Neither dexamethasone, nor compound A affects myofibroblast cell viability. However, compound A retards the growth of this myofibroblast cell line. Additionally, dexamethasone can inhibit the expression of Tenascin C, hepatocyte growth factor, and TGFβ, which are all factors known for their impact on colon cancer cell invasion, in a glucocorticoid receptor-dependent manner. In contrast, compound A can only slightly diminish the expression of just hepatocyte growth factor, and not tenascin C or TGFβ. Combined, our results expose new tumor microenvironment-modulating effects of

  11. The impact of pre- and/or probiotics on human colonic metabolism: does it affect human health?

    PubMed

    De Preter, Vicky; Hamer, Henrike M; Windey, Karen; Verbeke, Kristin

    2011-01-01

    Since many years, the role of the colonic microbiota in maintaining the host's overall health and well-being has been recognized. Dietary modulation of the microbiota composition and activity has been achieved by the use of pre-, pro- and synbiotics. In this review, we will summarize the available evidence on the modification of bacterial metabolism by dietary intervention with pre-, pro- and synbiotics. Enhanced production of SCFA as a marker of increased saccharolytic fermentation is well documented in animal and in vitro studies. Decreased production of potentially toxic protein fermentation metabolites, such as sulfides, phenolic and indolic compounds, has been less frequently demonstrated. Besides, pre-, pro- and synbiotics also affect other metabolic pathways such as the deconjugation of secondary bile acids, bacterial enzyme activities and mineral absorption. Data from human studies are less conclusive. The emergence of new analytical techniques such as metabolite profiling has revealed new pathways affected by dietary intervention. However, an important challenge for current and future research is to relate changes in bacterial metabolism to concrete health benefits. Potential targets and expected benefits have been identified: reduced risk for the metabolic syndrome and prevention of colorectal cancer. PMID:21207512

  12. Virosecurinine induces apoptosis by affecting Bcl-2 and Bax expression in human colon cancer SW480 cells.

    PubMed

    Chen, Chuan-Rong; Xia, Yong-Hui; Yao, Shu-Yan; Zhang, Qing; Wang, Ying; Ji, Zhao-Ning

    2012-04-01

    Virosecurinine, the major alkaloid isolated from Securinega suffruticosa Pall Rehd was found to exhibit growth inhibition and cytotoxicity against huaman colon cancer SW480 cells via the microculture tetrazolium (MTT) assay. Due to its greater cytotoxic potency and selectivity towards SW480 cells, flow cytometry was used to analyze the cell cycle distribution of control and treated SW480 cells whereas Annexin V-FITC/PI flow cytometry analysis was carried out to confirm apoptosis induced by virosecurinine in SW480 cells. Apoptotic regulatory genes were determined by RT-PCR analysis. Virosecurinine was found to induce G1/S cell cycle arrest which led to predominantly apoptotic mode of cell death. Mechanistically, virosecurinine was found to up-regulated the Bax gene expression and down-regulated the Bcl-2 expression in SW480, The ratio of Bcl-2 to Bax was significantly decreased. Hence, we suggest that virosecurinine induced apoptosis in SW480 cells by affecting the expression of bcl-2 and bax. PMID:22570942

  13. Proliferation rate but not mismatch repair affects the long-term response of colon carcinoma cells to 5FU treatment.

    PubMed

    Choudhary, B; Hanski, M L; Zeitz, M; Hanski, C

    2012-07-01

    The role of mismatch repair (MMR) in the response of colon carcinoma cells to 5-fluorouracil (5FU) is not well understood. In most of the in vitro studies only short-term response was investigated. We focussed here on the influence of MMR status on the mechanism of the short- and long-term response to clinically relevant 5FU concentrations by using isogenic or semiisogenic cell line pairs expressing/nonexpressing the hMLH1 protein, an important component of the MMR system. We show that the lower survival of MMR-proficient than of MMR-deficient cells in the clonogenic survival assay is due to a more frequent early cell arrest and to subsequent senescence. By contrast, the long-term cell growth after treatment, which is also affected by long-term arrest and senescence, is independent from the MMR status. The overall effect on the long-term cell growth is a cumulative result of cell proliferation rate-dependent growth inhibition, apoptosis and necrotic cell death. The main long-term cytotoxic effect of 5FU is the inhibition of growth while apoptosis and the necrotic cell death are minor contributions.

  14. Study on spectral parameters and the support vector machine in surface enhanced Raman spectroscopy of serum for the detection of colon cancer

    NASA Astrophysics Data System (ADS)

    Li, Xiaozhou; Yang, Tianyue; Li, Siqi; Yao, Jun; Song, Youtao; Wang, Deli; Ding, Jianhua

    2015-11-01

    Surface enhanced Raman spectroscopy (SERS) has been recognized as an effective tool for the analysis of tissue samples and biofluids. In this work, a total of 27 spectral parameters were chosen and compared using SERS. Four parameters with the highest prediction ability were selected for further support vector machine (SVM) analysis. As a comparison, principal component analysis (PCA) was used on the same dataset for feature extraction. SVM was used with the above two data reduction methods separately to differentiate colon cancer and the control groups. Serum taken from 52 colon cancer patients and 60 healthy volunteers were collected and tested by SERS. The accuracy for Parameter-SVM was 95.0%, the sensitivity was 96.2%, and the specificity was 95.5%, which was much higher than the results using only one parameter, while for PCA-SVM, the results are 93.3%, 92.3%, and 92.9%, respectively. These results demonstrate that the SERS analysis method can be used to identify serum differences between colon cancer patients and normal people.

  15. Measures of GCM Performance as Functions of Model Parameters Affecting Clouds and Radiation

    NASA Astrophysics Data System (ADS)

    Jackson, C.; Mu, Q.; Sen, M.; Stoffa, P.

    2002-05-01

    This abstract is one of three related presentations at this meeting dealing with several issues surrounding optimal parameter and uncertainty estimation of model predictions of climate. Uncertainty in model predictions of climate depends in part on the uncertainty produced by model approximations or parameterizations of unresolved physics. Evaluating these uncertainties is computationally expensive because one needs to evaluate how arbitrary choices for any given combination of model parameters affects model performance. Because the computational effort grows exponentially with the number of parameters being investigated, it is important to choose parameters carefully. Evaluating whether a parameter is worth investigating depends on two considerations: 1) does reasonable choices of parameter values produce a large range in model response relative to observational uncertainty? and 2) does the model response depend non-linearly on various combinations of model parameters? We have decided to narrow our attention to selecting parameters that affect clouds and radiation, as it is likely that these parameters will dominate uncertainties in model predictions of future climate. We present preliminary results of ~20 to 30 AMIPII style climate model integrations using NCAR's CCM3.10 that show model performance as functions of individual parameters controlling 1) critical relative humidity for cloud formation (RHMIN), and 2) boundary layer critical Richardson number (RICR). We also explore various definitions of model performance that include some or all observational data sources (surface air temperature and pressure, meridional and zonal winds, clouds, long and short-wave cloud forcings, etc...) and evaluate in a few select cases whether the model's response depends non-linearly on the parameter values we have selected.

  16. Students' Perspective (Age Wise, Gender Wise and Year Wise) of Parameters Affecting the Undergraduate Engineering Education

    ERIC Educational Resources Information Center

    Kumari, Neeraj

    2014-01-01

    The objective of the study is to examine the students' perspective (age wise, gender wise and year wise) of parameters affecting the undergraduate engineering education system present in a private technical institution in NCR [National Capital Region], Haryana. It is a descriptive type of research in nature. The data has been collected with the…

  17. A Case Study Showing Parameters Affecting the Quality of Education: Faculty Perspective

    ERIC Educational Resources Information Center

    Kumari, Neeraj

    2014-01-01

    The study aims to examine the faculty members' perspective (age Wise, Gender Wise and Work Experience wise) of parameters affecting the quality of education in an affiliated Undergraduate Engineering Institution in Haryana. It is a descriptive type of research. The data has been collected with the help of 'Questionnaire Based Survey'. The sample…

  18. Weed control and cover crop management affect mycorrhizal colonization of grapevine roots and arbuscular mycorrhizal fungal spore populations in a California vineyard.

    PubMed

    Baumgartner, Kendra; Smith, Richard F; Bettiga, Larry

    2005-03-01

    Arbuscular mycorrhizal (AM) fungi naturally colonize grapevines in California vineyards. Weed control and cover cropping may affect AM fungi directly, through destruction of extraradical hyphae by soil disruption, or indirectly, through effects on populations of mycorrhizal weeds and cover crops. We examined the effects of weed control (cultivation, post-emergence herbicides, pre-emergence herbicides) and cover crops (Secale cereale cv. Merced rye, x Triticosecale cv.Trios 102) on AM fungi in a Central Coast vineyard. Seasonal changes in grapevine mycorrhizal colonization differed among weed control treatments, but did not correspond with seasonal changes in total weed frequency. Differences in grapevine colonization among weed control treatments may be due to differences in mycorrhizal status and/or AM fungal species composition among dominant weed species. Cover crops had no effect on grapevine mycorrhizal colonization, despite higher spring spore populations in cover cropped middles compared to bare middles. Cover crops were mycorrhizal and shared four AM fungal species (Glomus aggregatum, G. etunicatum, G. mosseae, G. scintillans) in common with grapevines. Lack of contact between grapevine roots and cover crop roots may have prevented grapevines from accessing higher spore populations in the middles. PMID:15133724

  19. [Research on the performance comparing and building of affective computing database based on physiological parameters].

    PubMed

    Li, Xin; Du, Xiaojuan; Zhang, Yunpeng; Ying, Lijuan; Li, Changwuz

    2014-08-01

    The validity and reasonableness of emotional data are the key issues in the cognitive affective computing research. Effects of the emotion recognition are decided by the quality of selected data directly. Therefore, it is an important part of affective computing research to build affective computing database with good performance, so that it is the hot spot of research in this field. In this paper, the performance of two classical cognitive affective computing databases, the Massachusetts Institute of Technology (MIT) cognitive affective computing database and Germany Augsburg University emotion recognition database were compared, their data structure and data types were compared respectively, and emotional recognition effect based on the data were studied comparatively. The results indicated that the analysis based on the physical parameters could get the effective emotional recognition, and would be a feasible method of pressure emotional evaluation. Because of the lack of stress emotional evaluation data based on the physiological parameters domestically, there is not a public stress emotional database. We hereby built a dataset for the stress evaluation towards the high stress group in colleges, candidates of postgraduates of Ph. D and master as the subjects. We then acquired their physiological parameters, and performed the pressure analysis based on this database. The results indicated that this dataset had a certain reference value for the stress evaluation, and we hope this research can provide a reference and support for emotion evaluation and analysis.

  20. Management of colonic volvulus.

    PubMed

    Gingold, Daniel; Murrell, Zuri

    2012-12-01

    Colonic volvulus is a common cause of large bowel obstruction worldwide. It can affect all parts of the colon, but most commonly occurs in the sigmoid and cecal areas. This disease has been described for centuries, and was studied by Hippocrates himself. Currently, colonic volvulus is the third most common cause of large bowel obstruction worldwide, and is responsible for ∼15% of large bowel obstructions in the United States. This article will discuss the history of colonic volvulus, and the predisposing factors that lead to this disease. Moreover, the epidemiology and diagnosis of each type of colonic volvulus, along with the various treatment options will be reviewed. PMID:24294126

  1. Modulation of intracellular calcium levels by calcium lactate affects colon cancer cell motility through calcium-dependent calpain.

    PubMed

    Sundaramoorthy, Pasupathi; Sim, Jae Jun; Jang, Yeong-Su; Mishra, Siddhartha Kumar; Jeong, Keun-Yeong; Mander, Poonam; Chul, Oh Byung; Shim, Won-Sik; Oh, Seung Hyun; Nam, Ky-Youb; Kim, Hwan Mook

    2015-01-01

    Cancer cell motility is a key phenomenon regulating invasion and metastasis. Focal adhesion kinase (FAK) plays a major role in cellular adhesion and metastasis of various cancers. The relationship between dietary supplementation of calcium and colon cancer has been extensively investigated. However, the effect of calcium (Ca2+) supplementation on calpain-FAK-motility is not clearly understood. We sought to identify the mechanism of FAK cleavage through Ca2+ bound lactate (CaLa), its downstream signaling and role in the motility of human colon cancer cells. We found that treating HCT116 and HT-29 cells with CaLa immediately increased the intracellular Ca2+ (iCa2+) levels for a prolonged period of time. Ca2+ influx induced cleavage of FAK into an N-terminal FAK (FERM domain) in a dose-dependent manner. Phosphorylated FAK (p-FAK) was also cleaved in to its p-N-terminal FAK. CaLa increased colon cancer cells motility. Calpeptin, a calpain inhibitor, reversed the effects of CaLa on FAK and pFAK cleavage in both cancer cell lines. The cleaved FAK translocates into the nucleus and modulates p53 stability through MDM2-associated ubiquitination. CaLa-induced Ca2+ influx increased the motility of colon cancer cells was mediated by calpain activity through FAK and pFAK protein destabilization. In conclusion, these results suggest that careful consideration may be given in deciding dietary Ca2+ supplementation to patient undergoing treatment for metastatic cancer.

  2. Modulation of Intracellular Calcium Levels by Calcium Lactate Affects Colon Cancer Cell Motility through Calcium-Dependent Calpain

    PubMed Central

    Sundaramoorthy, Pasupathi; Sim, Jae Jun; Jang, Yeong-Su; Mishra, Siddhartha Kumar; Jeong, Keun-Yeong; Mander, Poonam; Chul, Oh Byung; Shim, Won-Sik; Oh, Seung Hyun; Nam, Ky-Youb; Kim, Hwan Mook

    2015-01-01

    Cancer cell motility is a key phenomenon regulating invasion and metastasis. Focal adhesion kinase (FAK) plays a major role in cellular adhesion and metastasis of various cancers. The relationship between dietary supplementation of calcium and colon cancer has been extensively investigated. However, the effect of calcium (Ca2+) supplementation on calpain-FAK-motility is not clearly understood. We sought to identify the mechanism of FAK cleavage through Ca2+ bound lactate (CaLa), its downstream signaling and role in the motility of human colon cancer cells. We found that treating HCT116 and HT-29 cells with CaLa immediately increased the intracellular Ca2+ (iCa2+) levels for a prolonged period of time. Ca2+ influx induced cleavage of FAK into an N-terminal FAK (FERM domain) in a dose-dependent manner. Phosphorylated FAK (p-FAK) was also cleaved in to its p-N-terminal FAK. CaLa increased colon cancer cells motility. Calpeptin, a calpain inhibitor, reversed the effects of CaLa on FAK and pFAK cleavage in both cancer cell lines. The cleaved FAK translocates into the nucleus and modulates p53 stability through MDM2-associated ubiquitination. CaLa-induced Ca2+ influx increased the motility of colon cancer cells was mediated by calpain activity through FAK and pFAK protein destabilization. In conclusion, these results suggest that careful consideration may be given in deciding dietary Ca2+ supplementation to patient undergoing treatment for metastatic cancer. PMID:25629974

  3. Xylo-oligosaccharides and inulin affect genotoxicity and bacterial populations differently in a human colonic simulator challenged with soy protein.

    PubMed

    Christophersen, Claus T; Petersen, Anne; Licht, Tine R; Conlon, Michael A

    2013-09-23

    High dietary intakes of some protein sources, including soy protein, can increase colonic DNA damage in animals, whereas some carbohydrates attenuate this. We investigated whether inulin and xylo-oligosaccharides (XOS) could be protective against DNA strand breaks by adding them to a human colonic simulator consisting of a proximal vessel (PV) (pH 5.5) and a distal vessel (DV) (pH 6.8) inoculated with human faeces and media containing soy protein. Genotoxicity of the liquid phase and microbial population changes in the vessels were measured. Soy protein (3%) was fermented with 1% low amylose cornstarch for 10 day followed by soy protein with 1% XOS or 1% inulin for 10 day. Inulin did not alter genotoxicity but XOS significantly reduced PV genotoxicity and increased DV genotoxicity. Inulin and XOS significantly increased butyrate concentration in the DV but not PV. Numbers of the key butyrate-producing bacterium Faecalibacterium prausnitzii were significantly increased in the PV and DV by inulin but significantly decreased by XOS in both vessels. Other bacteria examined were also significantly impacted by the carbohydrate treatments or by the vessel (i.e., pH). There was a significant overall inverse correlation between levels of damage induced by the ferments and levels of sulphate-reducing bacteria, Bacteroides fragilis, and acetate. In conclusion, dietary XOS can potentially modulate the genotoxicity of the colonic environment and specific bacterial groups and short chain fatty acids may mediate this.

  4. Colon cancer

    MedlinePlus

    Colorectal cancer; Cancer - colon; Rectal cancer; Cancer - rectum; Adenocarcinoma - colon; Colon - adenocarcinoma ... In the United States, colorectal cancer is one of the leading causes of deaths due to cancer. Early diagnosis can often lead to a complete cure. Almost ...

  5. Variation in Growth, Colonization of Maize, and Metabolic Parameters of GFP- and DsRed-Labeled Fusarium verticillioides Strains.

    PubMed

    Wu, Lei; Conner, R L; Wang, Xiaoming; Xu, Rongqi; Li, Hongjie

    2016-08-01

    Autofluorescent proteins are frequently applied as visual markers in the labeling of filamentous fungi. Genes gfp and DsRed were transformed into the genome of Fusarium verticillioides via the Agrobacterium tumefaciens-mediated transformation method. The selected transformants displayed a bright green or red fluorescence in all the organelles of the growing fungal mycelia and spores (except for the vacuoles) both in cultures and in the maize (Zea mays) roots they colonized. The results of gene-specific polymerase chain reaction (PCR) analysis and the thermal asymmetrical interlaced (TAIL)-PCR analysis demonstrated that gfp and DsRed were integrated on different chromosomes of the fungus. Reductions in the colony growth on the plates at pH 4.0 and 5.5 was observed for the green fluorescent protein (GFP)-transformant G3 and the DsRed-transformant R4, but transformants G4 and R1 grew as well as the wild-type strain at pH 4.0. The speed of growth of all the transformants was similar to the wild-type strain at pH ≥ 7. The insertion of gfp and DsRed did not alter the production of extracellular enzymes and fumonisin B by F. verticillioides. The transformants expressing GFP and DsRed proteins were able to colonize maize roots. However, the four transformants examined produced fewer CFU in the root samples than the wild-type strain during a sampling period of 7 to 28 days after inoculation. PMID:27088391

  6. An analysis of the meteorological parameters affecting ambient concentrations of acid aerosols in Uniontown, Pennsylvania

    NASA Astrophysics Data System (ADS)

    Zelenka, Michael P.

    Ambient concentrations of aerosol strong acidity (H +) that were collected in Uniontown, Pennsylvania, during the summer of 1990 were evaluated to determine the relationships between meteorology and the magnitude of the H + concentrations. An extensive database containing 17 meteorological parameters was compiled for the Uniontown - Pittsburgh region. The database included both surface and upper air meteorological parameters. Concentrations of ambient acid sulfate aerosols collected in Uniontown, Pennsylvania, in the summer of 1990 were greatly affected by both local and regional meteorological conditions. Seven distinct meteorological synoptic types or regimes were identified for the summer months. A clear association was shown between episodic events of elevated ambient H + concentrations and one of the regimes, referred to here as synoptic type 5, which occurred when an anticyclone set up to the east of the mid-Atlantic states. Much of the variability (approximately 45%) in H + concentrations for the overall model was explained by the surface air temperature. Approximately 10% of the H' variability was explained by westerly winds as expressed by the U components of the morning 850 mb wind and the mean daily surface wind at Uniontown. Results showed that for days under the influence of synoptic type 5, which was associated with the highest levels of ambient H', the surface temperature explained approximately one-third of the variability in H' concentrations. The height of the mixing layer also affected the variability in H + concentrations, accounting for nearly a quarter of the variance. These results show that an analysis of the surface wind speed and direction alone will not adequately explain the variability in the concentrations of ambient acid aerosols. Analyses of the meteorological parameters affecting ambient concentrations of acid aerosols should include the mixing height, as well as the temperature, wind speed, and wind direction; both at the surface

  7. Identifying critical road geometry parameters affecting crash rate and crash type.

    PubMed

    Othman, Sarbaz; Thomson, Robert; Lannér, Gunnar

    2009-10-01

    The objective of this traffic safety investigation was to find critical road parameters affecting crash rate (CR). The study was based on crash and road maintenance data from Western Sweden. More than 3000 crashes, reported from 2000 to 2005 on median-separated roads, were collected and combined with road geometric and surface data. The statistical analysis showed variations in CR when road elements changed confirming that road characteristics affect CR. The findings indicated that large radii right-turn curves were more dangerous than left curves, in particular, during lane changing manoeuvres. However sharper curves are more dangerous in both left and right curves. Moreover, motorway carriageways with no or limited shoulders have the highest CR when compared to other carriageway widths, while one lane carriageway sections on 2+1 roads were the safest. Road surface results showed that both wheel rut depth and road roughness have negative impacts on traffic safety.

  8. Aboveground Epichloë coenophiala-Grass Associations Do Not Affect Belowground Fungal Symbionts or Associated Plant, Soil Parameters.

    PubMed

    Slaughter, Lindsey C; McCulley, Rebecca L

    2016-10-01

    Cool season grasses host multiple fungal symbionts, such as aboveground Epichloë endophytes and belowground arbuscular mycorrhizal fungi (AMF) and dark septate endophytes (DSEs). Asexual Epichloë endophytes can influence root colonization by AMF, but the type of interaction-whether antagonistic or beneficial-varies. In Schedonorus arundinaceus (tall fescue), Epichloë coenophiala can negatively affect AMF, which may impact soil properties and ecosystem function. Within field plots of S. arundinaceus that were either E. coenophiala-free (E-), infected with the common, mammal-toxic E. coenophiala strain (CTE+), or infected with one of two novel, non-toxic strains (AR542 NTE+ and AR584 NTE+), we hypothesized that (1) CTE+ would decrease AMF and DSE colonization rates and reduce soil extraradical AMF hyphae compared to E- or NTE+, and (2) this would lead to E- and NTE+ plots having greater water stable soil aggregates and C than CTE+. E. coenophiala presence and strain did not significantly alter AMF or DSE colonization, nor did it affect extraradical AMF hypha length, soil aggregates, or aggregate-associated C and N. Soil extraradical AMF hypha length negatively correlated with root AMF colonization. Our results contrast with previous demonstrations that E. coenophiala symbiosis inhibits belowground AMF communities. In our mesic, relatively nutrient-rich grassland, E. coenophiala symbiosis did not antagonize belowground symbionts, regardless of strain. Manipulating E. coenophiala strains within S. arundinaceus may not significantly alter AMF communities and nutrient cycling, yet we must further explore these relationships under different soils and environmental conditions given that symbiont interactions can be important in determining ecosystem response to global change.

  9. Aboveground Epichloë coenophiala-Grass Associations Do Not Affect Belowground Fungal Symbionts or Associated Plant, Soil Parameters.

    PubMed

    Slaughter, Lindsey C; McCulley, Rebecca L

    2016-10-01

    Cool season grasses host multiple fungal symbionts, such as aboveground Epichloë endophytes and belowground arbuscular mycorrhizal fungi (AMF) and dark septate endophytes (DSEs). Asexual Epichloë endophytes can influence root colonization by AMF, but the type of interaction-whether antagonistic or beneficial-varies. In Schedonorus arundinaceus (tall fescue), Epichloë coenophiala can negatively affect AMF, which may impact soil properties and ecosystem function. Within field plots of S. arundinaceus that were either E. coenophiala-free (E-), infected with the common, mammal-toxic E. coenophiala strain (CTE+), or infected with one of two novel, non-toxic strains (AR542 NTE+ and AR584 NTE+), we hypothesized that (1) CTE+ would decrease AMF and DSE colonization rates and reduce soil extraradical AMF hyphae compared to E- or NTE+, and (2) this would lead to E- and NTE+ plots having greater water stable soil aggregates and C than CTE+. E. coenophiala presence and strain did not significantly alter AMF or DSE colonization, nor did it affect extraradical AMF hypha length, soil aggregates, or aggregate-associated C and N. Soil extraradical AMF hypha length negatively correlated with root AMF colonization. Our results contrast with previous demonstrations that E. coenophiala symbiosis inhibits belowground AMF communities. In our mesic, relatively nutrient-rich grassland, E. coenophiala symbiosis did not antagonize belowground symbionts, regardless of strain. Manipulating E. coenophiala strains within S. arundinaceus may not significantly alter AMF communities and nutrient cycling, yet we must further explore these relationships under different soils and environmental conditions given that symbiont interactions can be important in determining ecosystem response to global change. PMID:27502203

  10. Experimental analyses of the major parameters affecting the intensity of outbursts of coal and gas.

    PubMed

    Nie, W; Peng, S J; Xu, J; Liu, L R; Wang, G; Geng, J B

    2014-01-01

    With an increase in mining depth and production, the intensity and frequency of outburst of coal and gas have a tendency to increase. Estimating the intensity of outbursts of coal and gas plays an important role because of its relation with the risk value. In this paper, we described the semiquantitative relations between major parameters and intensity of outburst based on physical experiments. The results showed increment of geostress simulated by horizontal load (from 1.4, 2.4, 3.2, to 3.4 MPa) or vertical load (from 2, 3, 3.6, to 4 MPa) improved the relative intensity rate (3.763-7.403% and 1.273-7.99%); the increment of porosity (from 1.57, 2.51, 3, to 3.6%) improved the relative intensity rate from 3.8 to 13.8%; the increment of gas pressure (from 0, 0.5, 0.65, 0.72, 1, to 1.5 Mpa) induced the relative intensity rate to decrease from 38.22 to 0%; the increment of water content (from 0, 2, 4, to 8%) caused the relative intensity rate to drop from 5.425 to 0.5%. Furthermore, sensitivity and range analysis evaluates coupled factors affecting the relative intensity. In addition, the distinction with initiation of outburst of coal and gas affected by these parameters is discussed by the relative threshold of gas content rate.

  11. Experimental Analyses of the Major Parameters Affecting the Intensity of Outbursts of Coal and Gas

    PubMed Central

    Nie, W.; Peng, S. J.; Xu, J.; Liu, L. R.; Wang, G.; Geng, J. B.

    2014-01-01

    With an increase in mining depth and production, the intensity and frequency of outburst of coal and gas have a tendency to increase. Estimating the intensity of outbursts of coal and gas plays an important role because of its relation with the risk value. In this paper, we described the semiquantitative relations between major parameters and intensity of outburst based on physical experiments. The results showed increment of geostress simulated by horizontal load (from 1.4, 2.4, 3.2, to 3.4 MPa) or vertical load (from 2, 3, 3.6, to 4 MPa) improved the relative intensity rate (3.763–7.403% and 1.273–7.99%); the increment of porosity (from 1.57, 2.51, 3, to 3.6%) improved the relative intensity rate from 3.8 to 13.8%; the increment of gas pressure (from 0, 0.5, 0.65, 0.72, 1, to 1.5 Mpa) induced the relative intensity rate to decrease from 38.22 to 0%; the increment of water content (from 0, 2, 4, to 8%) caused the relative intensity rate to drop from 5.425 to 0.5%. Furthermore, sensitivity and range analysis evaluates coupled factors affecting the relative intensity. In addition, the distinction with initiation of outburst of coal and gas affected by these parameters is discussed by the relative threshold of gas content rate. PMID:25162042

  12. Modeling of mouse eye and errors in ocular parameters affecting refractive state

    NASA Astrophysics Data System (ADS)

    Bawa, Gurinder

    Rodents eye are particularly used to study refractive error state of an eye and development of refractive eye. Genetic organization of rodents is similar to that of humans, which makes them interesting candidates to be researched upon. From rodents family mice models are encouraged over rats because of availability of genetically engineered models. Despite of extensive work that has been performed on mice and rat models, still no one is able to quantify an optical model, due to variability in the reported ocular parameters. In this Dissertation, we have extracted ocular parameters and generated schematics of eye from the raw data from School of Medicine, Detroit. In order to see how the rays would travel through an eye and the defects associated with an eye; ray tracing has been performed using ocular parameters. Finally we have systematically evaluated the contribution of various ocular parameters, such as radii of curvature of ocular surfaces, thicknesses of ocular components, and refractive indices of ocular refractive media, using variational analysis and a computational model of the rodent eye. Variational analysis revealed that variation in all the ocular parameters does affect the refractive status of the eye, but depending upon the magnitude of the impact those parameters are listed as critical or non critical. Variation in the depth of the vitreous chamber, thickness of the lens, radius of the anterior surface of the cornea, radius of the anterior surface of the lens, as well as refractive indices for the lens and vitreous, appears to have the largest impact on the refractive error and thus are categorized as critical ocular parameters. The radii of the posterior surfaces of the cornea and lens have much smaller contributions to the refractive state, while the radii of the anterior and posterior surfaces of the retina have no effect on the refractive error. These data provide the framework for further refinement of the optical models of the rat and mouse

  13. Dietary choice affects Shiga toxin-producing Escherichia coli (STEC) O157:H7 colonization and disease.

    PubMed

    Zumbrun, Steven D; Melton-Celsa, Angela R; Smith, Mark A; Gilbreath, Jeremy J; Merrell, D Scott; O'Brien, Alison D

    2013-06-01

    The likelihood that a single individual infected with the Shiga toxin (Stx)-producing, food-borne pathogen Escherichia coli O157:H7 will develop a life-threatening sequela called the hemolytic uremic syndrome is unpredictable. We reasoned that conditions that enhance Stx binding and uptake within the gut after E. coli O157:H7 infection should result in greater disease severity. Because the receptor for Stx, globotriaosylceramide, is up-regulated in the presence of butyrate in vitro, we asked whether a high fiber diet (HFD) that reportedly enhances butyrate production by normal gut flora can influence the outcome of an E. coli O157 infection in mice. To address that question, groups of BALB/c mice were fed high (10%) or low (2%) fiber diets and infected with E. coli O157:H7 strain 86-24 (Stx2+). Mice fed an HFD exhibited a 10- to 100-fold increase in colonization, lost 15% more body weight, exhibited signs of morbidity, and had 25% greater mortality relative to the low fiber diet (LFD)-fed group. Additionally, sections of intestinal tissue from HFD-fed mice bound more Stx1 and expressed more globotriaosylceramide than did such sections from LFD-fed mice. Furthermore, the gut microbiota of HFD-fed mice compared with LFD-fed mice contained reduced levels of native Escherichia species, organisms that might protect the gut from colonization by incoming E. coli O157:H7. Taken together, these results suggest that susceptibility to infection and subsequent disease after ingestion of E. coli O157:H7 may depend, at least in part, on individual diet and/or the capacity of the commensal flora to produce butyrate.

  14. Assessment, modeling and optimization of parameters affecting the formation of disinfection by-products in water.

    PubMed

    Gougoutsa, Chrysa; Christophoridis, Christophoros; Zacharis, Constantinos K; Fytianos, Konstantinos

    2016-08-01

    This study focused on (a) the development of a screening methodology, in order to determine the main experimental variables affecting chlorinated and brominated disinfection by-product (DBP) formation in water during chlorination experiments and (b) the application of a central composite design (CCD) using response surface methodology (RSM) for the mathematical description and optimization of DBP formation. Chlorine dose and total organic carbon (TOC) were proven to be the main factors affecting the formation of total chlorinated DBPs, while chlorine dose and bromide concentration were the main parameters affecting the total brominated THMs. Longer contact time promoted a rise in chlorinated DBPs' concentration even in the presence of a minimal amount of organic matter. A maximum production of chlorinated DBPs was observed under a medium TOC value and it reduced at high TOC concentrations, possibly due to the competitive production of brominated THMs. The highest concentrations of chlorinated THMs were observed at chlorine dose 10 mg L(-1) and TOC 5.5 mg L(-1). The formation of brominated DBPs is possible even with a minimum amount of NaOCl in the presence of high concentration of bromide ions. Brominated DBPs were observed in maximum concentrations using 8 mg L(-1) of chlorine in the presence of 300 μg L(-1) bromides. PMID:27178297

  15. Selection of meteorological parameters affecting rainfall estimation using neuro-fuzzy computing methodology

    NASA Astrophysics Data System (ADS)

    Hashim, Roslan; Roy, Chandrabhushan; Motamedi, Shervin; Shamshirband, Shahaboddin; Petković, Dalibor; Gocic, Milan; Lee, Siew Cheng

    2016-05-01

    Rainfall is a complex atmospheric process that varies over time and space. Researchers have used various empirical and numerical methods to enhance estimation of rainfall intensity. We developed a novel prediction model in this study, with the emphasis on accuracy to identify the most significant meteorological parameters having effect on rainfall. For this, we used five input parameters: wet day frequency (dwet), vapor pressure (e̅a), and maximum and minimum air temperatures (Tmax and Tmin) as well as cloud cover (cc). The data were obtained from the Indian Meteorological Department for the Patna city, Bihar, India. Further, a type of soft-computing method, known as the adaptive-neuro-fuzzy inference system (ANFIS), was applied to the available data. In this respect, the observation data from 1901 to 2000 were employed for testing, validating, and estimating monthly rainfall via the simulated model. In addition, the ANFIS process for variable selection was implemented to detect the predominant variables affecting the rainfall prediction. Finally, the performance of the model was compared to other soft-computing approaches, including the artificial neural network (ANN), support vector machine (SVM), extreme learning machine (ELM), and genetic programming (GP). The results revealed that ANN, ELM, ANFIS, SVM, and GP had R2 of 0.9531, 0.9572, 0.9764, 0.9525, and 0.9526, respectively. Therefore, we conclude that the ANFIS is the best method among all to predict monthly rainfall. Moreover, dwet was found to be the most influential parameter for rainfall prediction, and the best predictor of accuracy. This study also identified sets of two and three meteorological parameters that show the best predictions.

  16. Positional isomerism markedly affects the growth inhibition of colon cancer cells by NOSH-aspirin: COX inhibition and modeling☆

    PubMed Central

    Vannini, Federica; Chattopadhyay, Mitali; Kodela, Ravinder; Rao, Praveen P.N.; Kashfi, Khosrow

    2015-01-01

    We recently reported the synthesis of NOSH-aspirin, a novel hybrid that releases both nitric oxide (NO) and hydrogen sulfide (H2S). In NOSH-aspirin, the two moieties that release NO and H2S are covalently linked at the 1, 2 positions of acetyl salicylic acid, i.e. ortho-NOSH-aspirin (o-NOSH-aspirin). In the present study, we compared the effects of the positional isomers of NOSH-ASA (o-NOSH-aspirin, m-NOSH-aspirin and p-NOSH-aspirin) to that of aspirin on growth of HT-29 and HCT 15 colon cancer cells, belonging to the same histological subtype, but with different expression of cyclooxygenase (COX) enzymes; HT-29 express both COX-1 and COX-2, whereas HCT 15 is COX-null. We also analyzed the effect of these compounds on proliferation and apoptosis in HT-29 cells. Since the parent compound aspirin, inhibits both COX-1 and COX-2, we also evaluated the effects of these compounds on COX-1 and COX-2 enzyme activities and also performed modeling of the interactions between the positional isomers of NOSH-aspirin and COX-1 and COX-2 enzymes. We observed that the three positional isomers of NOSH aspirin inhibited the growth of both colon cancer cell lines with IC50s in the nano-molar range. In particular in HT-29 cells the IC50s for growth inhibition were: o-NOSH-ASA, 0.04±0.011 µM; m-NOSH-ASA, 0.24±0.11 µM; p-NOSH-ASA, 0.46±0.17 µM; and in HCT 15 cells the IC50s for o-NOSH-ASA, m-NOSH-ASA, and p-NOSH-ASA were 0.062 ±0.006 µM, 0.092±0.004 µM, and 0.37±0.04 µM, respectively. The IC50 for aspirin in both cell lines was >5 mM at 24 h. The reduction of cell growth appeared to be mediated through inhibition of proliferation, and induction of apoptosis. All 3 positional isomers of NOSH-aspirin preferentially inhibited COX-1 over COX-2. These results suggest that the three positional isomers of NOSH-aspirin have the same biological actions, but that o-NOSH-ASA displayed the strongest anti-neoplastic potential. PMID:26319435

  17. Positional isomerism markedly affects the growth inhibition of colon cancer cells by NOSH-aspirin: COX inhibition and modeling.

    PubMed

    Vannini, Federica; Chattopadhyay, Mitali; Kodela, Ravinder; Rao, Praveen P N; Kashfi, Khosrow

    2015-12-01

    We recently reported the synthesis of NOSH-aspirin, a novel hybrid that releases both nitric oxide (NO) and hydrogen sulfide (H2S). In NOSH-aspirin, the two moieties that release NO and H2S are covalently linked at the 1, 2 positions of acetyl salicylic acid, i.e. ortho-NOSH-aspirin (o-NOSH-aspirin). In the present study, we compared the effects of the positional isomers of NOSH-ASA (o-NOSH-aspirin, m-NOSH-aspirin and p-NOSH-aspirin) to that of aspirin on growth of HT-29 and HCT 15 colon cancer cells, belonging to the same histological subtype, but with different expression of cyclooxygenase (COX) enzymes; HT-29 express both COX-1 and COX-2, whereas HCT 15 is COX-null. We also analyzed the effect of these compounds on proliferation and apoptosis in HT-29 cells. Since the parent compound aspirin, inhibits both COX-1 and COX-2, we also evaluated the effects of these compounds on COX-1 and COX-2 enzyme activities and also performed modeling of the interactions between the positional isomers of NOSH-aspirin and COX-1 and COX-2 enzymes. We observed that the three positional isomers of NOSH aspirin inhibited the growth of both colon cancer cell lines with IC50s in the nano-molar range. In particular in HT-29 cells the IC50s for growth inhibition were: o-NOSH-ASA, 0.04±0.011 µM; m-NOSH-ASA, 0.24±0.11 µM; p-NOSH-ASA, 0.46±0.17 µM; and in HCT 15 cells the IC50s for o-NOSH-ASA, m-NOSH-ASA, and p-NOSH-ASA were 0.062 ±0.006 µM, 0.092±0.004 µM, and 0.37±0.04 µM, respectively. The IC50 for aspirin in both cell lines was >5mM at 24h. The reduction of cell growth appeared to be mediated through inhibition of proliferation, and induction of apoptosis. All 3 positional isomers of NOSH-aspirin preferentially inhibited COX-1 over COX-2. These results suggest that the three positional isomers of NOSH-aspirin have the same biological actions, but that o-NOSH-ASA displayed the strongest anti-neoplastic potential.

  18. Campylobacter colonization and proliferation in the broiler chicken upon natural field challenge is not affected by the bird growth rate or breed.

    PubMed

    Gormley, Fraser J; Bailey, Richard A; Watson, Kellie A; McAdam, Jim; Avendaño, Santiago; Stanley, William A; Koerhuis, Alfons N M

    2014-11-01

    The zoonotic association between Campylobacter bacteria in poultry and humans has been characterized by decades of research which has attempted to elucidate the epidemiology of this complex relationship and to reduce carriage within poultry. While much work has focused on the mechanisms facilitating its success in contaminating chicken flocks (and other animal hosts), it remains difficult to consistently exclude Campylobacter under field conditions. Within the United Kingdom poultry industry, various bird genotypes with widely varying growth rates are available to meet market needs and consumer preferences. However, little is known about whether any differences in Campylobacter carriage exist across this modern broiler range. The aim of this study was to establish if a relationship exists between growth rate or breed and cecal Campylobacter concentration after natural commercial flock Campylobacter challenge. In one investigation, four pure line genotypes of various growth rates were grown together, while in the second, eight different commercial broiler genotypes were grown individually. In both studies, the Campylobacter concentration was measured in the ceca at 42 days of age, revealing no significant difference in cecal load between birds of different genotypes both in mixed- and single-genotype pens. This is important from a public health perspective and suggests that other underlying reasons beyond genotype are likely to control and affect Campylobacter colonization within chickens. Further studies to gain a better understanding of colonization dynamics and subsequent proliferation are needed, as are novel approaches to reduce the burden in poultry.

  19. Functional RelBE-Family Toxin-Antitoxin Pairs Affect Biofilm Maturation and Intestine Colonization in Vibrio cholerae

    PubMed Central

    Hay, Amanda J.; Zhong, Zengtao; Zhu, Jun; Kan, Biao

    2015-01-01

    Toxin–antitoxin (TA) systems are small genetic elements that typically encode a stable toxin and its labile antitoxin. These cognate pairs are abundant in prokaryotes and have been shown to regulate various cellular functions. Vibrio cholerae, a human pathogen that is the causative agent of cholera, harbors at least thirteen TA loci. While functional HigBA, ParDE have been shown to stabilize plasmids and Phd/Doc to mediate cell death in V. cholerae, the function of seven RelBE-family TA systems is not understood. In this study we investigated the function of the RelBE TA systems in V. cholerae physiology and found that six of the seven relBE loci encoded functional toxins in E. coli. Deletion analyses of each relBE locus indicate that RelBE systems are involved in biofilm formation and reactive oxygen species (ROS) resistance. Interestingly, all seven relBE loci are induced under the standard virulence induction conditions and two of the relBE mutants displayed a colonization defect, which was not due to an effect on virulence gene expression. Although further studies are needed to characterize the mechanism of action, our study reveals that RelBE systems are important for V. cholerae physiology. PMID:26275048

  20. Estimation of the growth kinetic parameters of Bacillus cereus spores as affected by pulsed light treatment.

    PubMed

    Aguirre, Juan S; de Fernando, Gonzalo García; Hierro, Eva; Hospital, Xavier F; Ordóñez, Juan A; Fernández, Manuela

    2015-06-01

    Quantitative microbial risk assessment requires the knowledge of the effect of food preservation technologies on the growth parameters of the survivors of the treatment. This is of special interest in the case of the new non-thermal technologies that are being investigated for minimal processing of foods. This is a study on the effect of pulsed light technology (PL) on the lag phase of Bacillus cereus spores surviving the treatment and the maximum growth rate (μmax) of the survivors after germination. The D value was estimated as 0.35 J/cm(2) and our findings showed that PL affected the kinetic parameters of the microorganism. A log linear relationship was observed between the lag phase and the intensity of the treatment. Increasing the lethality lengthened the mean lag phase and proportionally increased its variability. A polynomial regression was fitted between the μmax of the survivors and the inactivation achieved. The μmax decreased as intensity increased. From these data, and their comparison to published results on the effect of heat and e-beam irradiation on B. cereus spores, it was observed that the shelf-life of PL treated foods would be longer than those treated with heat and similar to irradiated ones. These findings offer information of interest for the implementation of PL for microbial decontamination in the food industry. PMID:25755081

  1. Estimation of the growth kinetic parameters of Bacillus cereus spores as affected by pulsed light treatment.

    PubMed

    Aguirre, Juan S; de Fernando, Gonzalo García; Hierro, Eva; Hospital, Xavier F; Ordóñez, Juan A; Fernández, Manuela

    2015-06-01

    Quantitative microbial risk assessment requires the knowledge of the effect of food preservation technologies on the growth parameters of the survivors of the treatment. This is of special interest in the case of the new non-thermal technologies that are being investigated for minimal processing of foods. This is a study on the effect of pulsed light technology (PL) on the lag phase of Bacillus cereus spores surviving the treatment and the maximum growth rate (μmax) of the survivors after germination. The D value was estimated as 0.35 J/cm(2) and our findings showed that PL affected the kinetic parameters of the microorganism. A log linear relationship was observed between the lag phase and the intensity of the treatment. Increasing the lethality lengthened the mean lag phase and proportionally increased its variability. A polynomial regression was fitted between the μmax of the survivors and the inactivation achieved. The μmax decreased as intensity increased. From these data, and their comparison to published results on the effect of heat and e-beam irradiation on B. cereus spores, it was observed that the shelf-life of PL treated foods would be longer than those treated with heat and similar to irradiated ones. These findings offer information of interest for the implementation of PL for microbial decontamination in the food industry.

  2. Effect of welding parameters on the heat-affected zone of AISI409 ferritic stainless steel

    NASA Astrophysics Data System (ADS)

    Ranjbarnodeh, Eslam; Hanke, Stefanie; Weiss, Sabine; Fischer, Alfons

    2012-10-01

    One of the main problems during the welding of ferritic stainless steels is severe grain growth within the heat-affected zone (HAZ). In the present study, the microstructural characteristics of tungsten inert gas (TIG) welded AISI409 ferritic stainless steel were investigated by electron backscattered diffraction (EBSD), and the effects of welding parameters on the grain size, local misorientation, and low-angle grain boundaries were studied. A 3-D finite element model (FEM) was developed to predict the effects of welding parameters on the holding time of the HAZ above the critical temperature of grain growth. It is found that the base metal is not fully recrystallized. During the welding, complete recrystallization is followed by severe grain growth. A decrease in the number of low-angle grain boundaries is observed within the HAZ. FEM results show that the final state of residual strains is caused by competition between welding plastic strains and their release by recrystallization. Still, the decisive factor for grain growth is heat input.

  3. Atmospheric parameters affecting sea ice losses in the context of gravity desalination

    NASA Astrophysics Data System (ADS)

    Li, Ying; Gu, Wei; Chao, Jinlong; Li, Lantao; Liu, Chengyu; Xu, Yinjun; Chang, Zhiyun; Wu, Linhong; Chen, Jie

    2015-08-01

    Gravity desalination is an important method for obtaining fresh water from sea ice; however, the large amount of ice that is exposed to air for long periods of time sublimates and evaporates, which results in a reduction of the freshwater resource. This paper describes a study of sea ice sublimation and evaporation performed during the winter of 2013 at the western shore of Bohai Bay, China, to determine the relationship between the amount of sublimation and evaporation and the atmospheric parameters. Substantial amounts of the Bohai sea ice sublimated and evaporated, ranging from 15 to 35 % of the total. The sublimation and evaporation amount was significantly different between the day and night and was greater in the daytime because of the relative humidity difference. Sublimation and evaporation is primarily affected by atmospheric parameters, and the amount of sublimation and evaporation exhibits a good linear relationship with the relative humidity and the wind speed; a comprehensive parameters formula was determined for the Bohai Rim in China. A 10 % increase of daily relative humidity will reduce approximately 1.5 kg/m2/day of the sublimation and evaporation, and the amount of sublimation and evaporation increases by 1.76 kg/m2/day when the daily wind speed increases by 1 m/s. To reduce the sublimation and evaporation and maximize the amount of this freshwater resource, gravity desalination sites should be selected where the wind speed is low and the relative humidity is high, i.e., the sea ice should be configured to reduce the adverse effects of sunlight, low humidity, and air turbulence.

  4. External Load Affects Ground Reaction Force Parameters Non-uniformly during Running in Weightlessness

    NASA Technical Reports Server (NTRS)

    DeWitt, John; Schaffner, Grant; Laughlin, Mitzi; Loehr, James; Hagan, R. Donald

    2004-01-01

    Long-term exposure to microgravity induces detrimefits to the musculcskdetal system (Schneider et al., 1995; LeBlanc et al., 2000). Treadmill exercise is used onboard the International Space Station as an exercise countermeasure to musculoskeletal deconditioning due to spaceflight. During locomotive exercise in weightlessness (0G), crewmembers wear a harness attached to an external loading mechanism (EL). The EL pulls the crewmember toward the treadmill, and provides resistive load during the impact and propulsive phases of gait. The resulting forces may be important in stimulating bone maintenance (Turner, 1998). The EL can be applied via a bungee and carabineer clip configuration attached to the harness and can be manipulated to create varying amounts of load levels during exercise. Ground-based research performed using a vertically mounted treadmill found that peak ground reaction forces (GRF) during running at an EL of less than one body weight (BW) are less than those that occur during running in normal gravity (1G) (Davis et al., 1996). However, it is not known how the GRF are affected by the EL in a true OG environment. Locomotion while suspended may result in biomechanics that differ from free running. The purpose of this investigation was to determine how EL affects peak impact force, peak propulsive force, loading rate, and impulse of the GRF during running in 0G. It was hypothesized that increasing EL would result in increases in each GRF parameter.

  5. CONTINUOSLY STIRRED TANK REACTOR PARAMETERS THAT AFFECT SLUDGE BATCH 6 SIMULANT PROPERTIES

    SciTech Connect

    Newell, J.; Lambert, D.; Stone, M.; Fernandez, A.

    2010-05-28

    ). Precipitated MnO{sub 2} is combined with metal nitrates and fed into the CSTR. The metals are precipitated by a caustic NaOH stream. The rates at which these streams are added allows for pH adjustment of the mixture. A graphical representation of this process is given in Figure 1. In using the CSTR method for developing simulant, there are various parameters that can be adjusted in order to effectuate a physical change in the resulting simulant: pH, temperature, mixing speed, and flow rate. How will changing these parameters affect the physical properties of the sludge simulant? The ability to determine which parameter affects a particular property could allow one to develop a simulant that would better match the physical characteristics of HLW sludge.

  6. Colonization pattern of aquatic hyphomycetes on leaf packs in subtropical stream.

    PubMed

    Abdel-Raheem, A M

    1997-01-01

    Steralized leaf pieces of eight plants (Eucalyptus rostrata, Phoenix dactylifera, Phragmites australis, Musa nana, Salix subserrata, Cyperus alopecuroides, Ricinus communis and Eichhornia crassipes) were submerged in the Nile stream. Thirty-nine species of aquatic hyphomycetes were colonized on the plant leaves. Eucalyptus was the best substratum (30 species) for colonization by aquatic hyphomycetes. Phoenix (14 species), Phragmites (11 species), Salix (9 species), Musa (8 species), Ricinus and Cyperus (6 species) were also good substrata for aquatic hyphomycetes colonization. Echhornia (aquatic plant) was not suitable for aquatic hyphomycetes colonization. Alatospora acuminata, Triscelophorus monosporus and Tetracladium marchalianum were found to be the major colonizers on all leaf materials. Temperature and dissolved oxygen were the highest physico-chemical parameters affecting the aquatic hyphomycetes colonization. These results indicate that aquatic hyphomycetes have been shown to be successful colonizers on plants leaf in river Nile in Egypt as subtropical region.

  7. Correlation between nitrate concentration in groundwater and parameters affecting aquifer intrinsic vulnerability

    NASA Astrophysics Data System (ADS)

    Debernardi, Laura; de Luca, Domenico Antonio; Lasagna, Manuela

    2008-08-01

    This paper is the result of a study which was carried out in order to verify if the traditional methods to evaluate the intrinsic vulnerability or vulnerability related parameters, are able to clarify the problem of nitrate pollution in groundwater. In particular, the aim was to evaluate limitations and problems connected to aquifer vulnerability methods applied to nitrate contamination prevision in groundwater. The investigation was carried out by comparing NO3 - concentrations, measured in March and November 2004 in the shallow aquifer, and the vulnerability classes, obtained by using GOD and TOT methods. Moreover, it deals with a comparison between NO3 - concentrations and single parameters (depth to water table, land use and nitrogen input). The study area is the plain sector of Piemonte (Northern Italy), where an unconfined aquifer nitrate contamination exists. In this area the anthropogenic presence is remarkable and the input of N-fertilizers and zootechnical effluents to the soil cause a growing amount of nitrates in groundwater. This approach, used in a large area (about 10,000 km2) and in several monitoring wells (about 500), allowed to compare the efficiency of different vulnerability methods and to verify the importance of every parameter on the nitrate concentrations in the aquifer. Furthermore it allowed to obtain interesting correlations in different hydrogeological situations. Correlations between depth to water table, land use and nitrogen input to the soil with nitrate concentrations in groundwater show unclear situations: in fact these comparisons describe the phenomenon trend and highlight the maximum nitrate concentrations for each circumstance but often show wide ranges of possible nitrate concentrations. The same situation could be observed by comparing vulnerability indexes and nitrate concentrations in groundwater. These results suggest that neither single parameters nor vulnerability methods (GOD and TOT) are able to describe individually

  8. Acute exposure to the biopesticide azadirachtin affects parameters in the gills of common carp (Cyprinus carpio).

    PubMed

    Murussi, Camila R; Costa, Maiara D; Leitemperger, Jossiele W; Flores-Lopes, Fábio; Menezes, Charlene C; Loebens, Luisa; de Avila, Luis Antonio; Rizzetti, Tiele M; Adaime, Martha B; Zanella, Renato; Loro, Vania L

    2016-02-01

    The biopesticide, azadirachtin (Aza) is less hazardous to the environment, but may cause several toxic effects in aquatic organisms. The Cyprinus carpio (n=12, for all concentrations) after 10days of acclimation under controlled conditions, were exposed at 20, 40, and 60μL/L of Aza during 96h. After this period, fish were anesthetized and euthanized then mucus layer and gills collected. In this study, the effects of exposure to different Aza concentrations were analysed through a set of biomarkers: Na(+)/K(+-)ATPase, lipid peroxidation (TBARS), protein carbonyl (PC), superoxide dismutase (SOD), glutathione-S-transferase (GST), catalase (CAT), glutathione peroxidase (GPx), non-protein thiols (NPSH), ascorbic acid (AsA) and histological parameters and, yet, protein and glucose concentration in the surface area of mucous layer. Na(+)K(+-)ATPase was inhibited at 40 and 60μL/L compared to control. TBARS decreased at 40μL/L compared to control. PC, SOD and GST increased at 60μL/L in comparison to control. CAT increased at 20 and 60μL/L, and GPx increased in all Aza concentrations compared to control. NPSH decreased and AsA increased in all concentrations in comparison to control. Histological analyses demonstrated an increase in the intensity of the damage with increasing Aza concentration. Alterations in histological examination were elevation and hypertrophy of the epithelial cells of the secondary filament, hypertrophy and hyperplasia of the mucous and chlorate cells and lamellar aneurism. Glucose and protein concentrations in mucus layer increased at 60μL/L compared to control. In general, we suggest that 60μL/L Aza concentration affected several parameters causing disruptions carp metabolism. PMID:26689640

  9. Parameters affecting in vitro oxidation/folding of maurotoxin, a four-disulphide-bridged scorpion toxin.

    PubMed Central

    di Luccio, E; Azulay, D O; Regaya, I; Fajloun, Z; Sandoz, G; Mansuelle, P; Kharrat, R; Fathallah, M; Carrega, L; Estève, E; Rochat, H; De Waard, M; Sabatier, J M

    2001-01-01

    Maurotoxin (MTX) is a 34-mer scorpion toxin cross-linked by four disulphide bridges that acts on various K(+) channel subtypes. MTX adopts a disulphide bridge organization of the type C1-C5, C2-C6, C3-C4 and C7-C8, and folds according to the common alpha/beta scaffold reported for other known scorpion toxins. Here we have investigated the process and kinetics of the in vitro oxidation/folding of reduced synthetic L-MTX (L-sMTX, where L-MTX contains only L-amino acid residues). During the oxidation/folding of reduced L-sMTX, the oxidation intermediates were blocked by iodoacetamide alkylation of free cysteine residues, and analysed by MS. The L-sMTX intermediates appeared sequentially over time from the least (intermediates with one disulphide bridge) to the most oxidized species (native-like, four-disulphide-bridged L-sMTX). The mathematical formulation of the diffusion-collision model being inadequate to accurately describe the kinetics of oxidation/folding of L-sMTX, we have formulated a derived mathematical description that better fits the experimental data. Using this mathematical description, we have compared for the first time the oxidation/folding of L-sMTX with that of D-sMTX, its stereoisomer that contains only D-amino acid residues. Several experimental parameters, likely to affect the oxidation/folding process, were studied further; these included temperature, pH, ionic strength, redox potential and concentration of reduced toxin. We also assessed the effects of some cellular enzymes, peptidylprolyl cis-trans isomerase (PPIase) and protein disulphide isomerase (PDI), on the folding pathways of reduced L-sMTX and D-sMTX. All the parameters tested affect the oxidative folding of sMTX, and the kinetics of this process were indistinguishable for L-sMTX and D-sMTX, except when stereospecific enzymes were used. The most efficient conditions were found to be: 50 mM Tris/HCl/1.4 mM EDTA, pH 7.5, supplemented by 0.5 mM PPIase and 50 units/ml PDI for 0.1 m

  10. Immunoaffinity chromatography in antivenomics studies: Various parameters that can affect the results.

    PubMed

    Sintiprungrat, Kitisak; Chaisuriya, Papada; Watcharatanyatip, Kamolwan; Ratanabanangkoon, Kavi

    2016-09-01

    Antivenomics is a recently developed powerful method for the study of antivenom antibody profiles when bound to homologous and heterologous snake venoms. The information obtained is useful in gaining an understanding of venom protein immunogenicity, antivenom potency and also for the improvement of antivenom potency and paraspecificity. The preferred method used in this type of study is immunoaffinity chromatography of the venom proteins on an antivenom IgG (or F(ab')2) column where the bound and unbound proteins can be separated and identified. However, there are some parameters of the immunochromatography that can significantly affect the binding of the proteins to the immunoaffinity matrix and lead to imprecise results in antivenom immunoprofiling. The present study demonstrated that the ligand density (mg IgG/ml of the matrix), the buffers used for binding and washing the venom proteins, the amount of venom loaded, the abundance of some venom protein(s) and the eluting buffers can significantly alter the binding of the proteins to the matrix and consequently the conclusions drawn from antivenomics studies. Furthermore, the immunochromatographic procedure can be extended to include the estimation of the relative affinity of venom protein-antibody interactions that can provide additional information useful to antivenomics study. PMID:27256919

  11. Important parameters affecting the cell voltage of aqueous electrical double-layer capacitors

    NASA Astrophysics Data System (ADS)

    Wu, Tzu-Ho; Hsu, Chun-Tsung; Hu, Chi-Chang; Hardwick, Laurence J.

    2013-11-01

    This study discusses and demonstrates how the open-circuit potential and charges stored in the working potential window on positive and negative electrodes affect the cell voltage of carbon-based electrical double-layer capacitors (EDLCs) in aqueous electrolytes. An EDLC consisting of two activated carbon electrodes is employed as the model system for identifying these key parameters although the potential window of water decomposition can be simply determined by voltammetric methods. First, the capacitive performances of an EDLC with the same charge on positive and negative electrodes are evaluated by cyclic voltammetric, charge-discharge, electrochemical impedance spectroscopic (EIS) analyses, and inductance-capacitance-resistance meter (LCR meter). The principles for obtaining the highest acceptable cell voltage of such symmetric ECs with excellent reversibility and capacitor-like behaviour are proposed. Aqueous charge-balanced EDLCs can be operated as high as 2.0 V with high energy efficiency (about 90%) and only 4% capacitance loss after the 600-cycle stability checking. The necessity of charge balance (but not capacitance balance) for positive and negative electrodes is substantiated from the lower acceptable cell voltage of charge-unbalanced EDLCs.

  12. Study of parameters affecting the correlation of engine and chassis dynamometers emission tests

    SciTech Connect

    Salem, M.I.; Bata, R.M.

    1996-12-31

    The inventory of exhaust gas emissions data of mobile sources is currently based on vehicle tailpipe testing techniques. However, heavy duty engines are used in numerous applications such as vehicles, boats, power generation units, ... etc. Consequently, engine emissions data based on vehicle tailpipe testing for a given engine is different for non-vehicle applications of that same engine. For this reason Environmental Protection Agency (EPA) engine certification standards are based on engine tests. Finding a correlation between the emissions of engine tests and the emissions of engine in vehicle chassis tests is the subject of this study. Efforts have been underway to study possible parameters affecting this cumbersome correlation of a particular power train configuration. Literature has been surveyed on related topics such as simulating road loads, power train components, and effects of engine accessories. This has been done as an initial step toward developing a correlation between the exhaust gas emission results of Chassis Dynamometer (CD) and Engine Dynamometer (ED) tests for a specific vehicle. This study could be conducted on a specific power train system, using specific testing cycles that will make this correlation possible.

  13. Parameters affecting the photocatalytic degradation of dyes using TiO2: a review

    NASA Astrophysics Data System (ADS)

    Reza, Khan Mamun; Kurny, ASW; Gulshan, Fahmida

    2015-12-01

    Traditional chemical, physical and biological processes for treating wastewater containing textile dye have such disadvantages as high cost, high energy requirement and generation of secondary pollution during treatment process. The advanced oxidation processes technology has been attracting growing attention for the decomposition of organic dyes. Such processes are based on the light-enhanced generation of highly reactive hydroxyl radicals, which oxidize the organic matter in solution and convert it completely into water, CO2 and inorganic compounds. In this presentation, the photocatalytic degradation of dyes in aqueous solution using TiO2 as photocatalyst under solar and UV irradiation has been reviewed. It is observed that the degradation of dyes depends on several parameters such as pH, catalyst concentration, substrate concentration and the presence of oxidants. Reaction temperature and the intensity of light also affect the degradation of dyes. Particle size, BET-surface area and different mineral forms of TiO2 also have influence on the degradation rate.

  14. Parameters affecting light-induced excess conductivity in amorphous silicon doping-modulated multilayers

    SciTech Connect

    Su, F.C.; Levine, S.; Vanier, P.E.

    1986-01-01

    The phenomenon of light-induced excess conductivity (LEC) which occurs in a-Si:H npnp doping-modulated multilayers is found experimentally to be dependent on several different factors. The concentrations of the dopants in n-type and p-type layers affect the Fermi level position, the height of the barriers, and also the density of defects. These parameters are altered by different choices of inert gas diluent (Ar or He) and substrate temperature T/sub s/. For a given set of deposition conditions, the LEC effect can be maximized by varying the layer thickness. With undiluted silane at T/sub s/ = 250/sup 0/C, the effect was relatively small, reaching a maximum in relatively thick layers (540 A). The largest effects were obtained for films deposited from silane diluted in helium, using thinner (330 A) layers. However, for films deposited from silane diluted in argon, the magnitude of the effect and optimum layer thickness was intermediate (440 A). When T/sub s/ was varied, a minimum in LEC was found near 200 to 250/sup 0/C. The influence of internal field was examined by using nini, pipi and npnp multilayers. The internal field is a necessary factor to observe a large LEC effect. A compensated film shows a small LEC effect.

  15. A study of the parameters affecting the effectiveness of Moringa oleifera in drinking water purification

    NASA Astrophysics Data System (ADS)

    Pritchard, M.; Craven, T.; Mkandawire, T.; Edmondson, A. S.; O'Neill, J. G.

    The powder obtained from the seeds of the Moringa oleifera tree has been shown to be an effective primary coagulant for water treatment. When the seeds are dried, dehusked, crushed and added to water, the powder acts as a coagulant binding colloidal particles and bacteria to form agglomerated particles (flocs), which settle allowing the clarified supernatant to be poured off. Very little research has been undertaken on the parameters affecting the effectiveness of M. oleifera, especially in Malawi, for purification of drinking water and there is a great need for further testing in this area. Conclusive data needs to be compiled to demonstrate the effects of various water parameters have on the efficiency of the seeds. A parametric study was undertaken at Leeds Metropolitan University, UK, with the aim to establish the most appropriate dosing method; the optimum dosage for removal of turbidity; the influence of pH and temperature; together with the shelf life of the M. oleifera seeds. The study revealed that the most suitable dosing method was to mix the powder into a concentrated paste, hence forming a stock suspension. The optimum M. oleifera dose, for turbidity values between 40 and 200 NTU, ranged between 30 and 55 mg/l. With turbidity set at 130 NTU and a M. oleifera dose within the optimum range at 50 mg/l, pH levels were varied between 4 and 9. It was discovered that the coagulant performance was not too sensitive to pH fluctuations when conditions were within the optimum range. The most efficient coagulation, determined by the greatest reduction in turbidity, occurred at pH 6.5. Alkaline conditions were overall more favourable than acidic conditions; pH 9 had an efficiency of 65% of optimum, whilst at pH 5 the efficiency dropped to around 55%. The efficiency further dropped at pH 4, where the powder only produced results of around 10% of optimum conditions. A temperature range of 4-60 °C was studied in this research. Colder waters (<15 °C) were found to

  16. Sperm treatment affects capacitation parameters and penetration ability of ejaculated and epididymal boar spermatozoa.

    PubMed

    Matás, C; Sansegundo, M; Ruiz, S; García-Vázquez, F A; Gadea, J; Romar, R; Coy, P

    2010-11-01

    This work was designed to study how this ability is affected by different sperm treatments routinely used for in vitro fertilization (IVF) assay. In this study, boar sperm samples from epididymal or ejaculated origin were processed by three different methods: left unwashed (NW group), washed in Dulbecco's phosphate-buffered saline supplemented with 0.1% BSA (BSA group), and washed on a Percoll(®) gradient (PERCOLL group). After preparation of semen samples, changes in motility patterns were studied by CASA, calcium uptake by spectrofluorimetry, and ROS generation, spontaneous acrosome reaction, and lipid disorder by means of flow cytometry. Finally IVF assays were also performed with the different semen samples and penetrability results evaluated at 2 and 4 h post insemination (hpi). Independently of the sperm treatment, epididymal spermatozoa showed higher values of progressive motility, percentage of live cells with low lipid disorder, and penetration ability at 4 hpi than the corresponding ejaculated spermatozoa. Ejaculated spermatozoa showed higher levels of calcium uptake, ROS generation and percentage of spontaneous acrosome reaction than epididymal sperm. Regarding sperm treatments, PERCOLL group showed the highest values for some motility parameters (linearity of the curvilinear trajectory, straightness, and average path velocity/curvilinear velocity), ROS generation and penetration ability at 2 and 4 hpi; however this same group showed the lowest values for sperm curvilinear velocity and lateral head displacement. From all experimental groups, ejaculated-PERCOLL-treated spermatozoa showed the highest fertilization ability after 2 hpi. Results suggest that capacitation pathways can be regulated by suitable treatments making the ejaculated sperm able to reach capacitation and fertilize oocytes in similar levels than epididymal spermatozoa, although most of the studied capacitation-associated changes do not correlate with this ability. PMID:20688369

  17. Sperm treatment affects capacitation parameters and penetration ability of ejaculated and epididymal boar spermatozoa.

    PubMed

    Matás, C; Sansegundo, M; Ruiz, S; García-Vázquez, F A; Gadea, J; Romar, R; Coy, P

    2010-11-01

    This work was designed to study how this ability is affected by different sperm treatments routinely used for in vitro fertilization (IVF) assay. In this study, boar sperm samples from epididymal or ejaculated origin were processed by three different methods: left unwashed (NW group), washed in Dulbecco's phosphate-buffered saline supplemented with 0.1% BSA (BSA group), and washed on a Percoll(®) gradient (PERCOLL group). After preparation of semen samples, changes in motility patterns were studied by CASA, calcium uptake by spectrofluorimetry, and ROS generation, spontaneous acrosome reaction, and lipid disorder by means of flow cytometry. Finally IVF assays were also performed with the different semen samples and penetrability results evaluated at 2 and 4 h post insemination (hpi). Independently of the sperm treatment, epididymal spermatozoa showed higher values of progressive motility, percentage of live cells with low lipid disorder, and penetration ability at 4 hpi than the corresponding ejaculated spermatozoa. Ejaculated spermatozoa showed higher levels of calcium uptake, ROS generation and percentage of spontaneous acrosome reaction than epididymal sperm. Regarding sperm treatments, PERCOLL group showed the highest values for some motility parameters (linearity of the curvilinear trajectory, straightness, and average path velocity/curvilinear velocity), ROS generation and penetration ability at 2 and 4 hpi; however this same group showed the lowest values for sperm curvilinear velocity and lateral head displacement. From all experimental groups, ejaculated-PERCOLL-treated spermatozoa showed the highest fertilization ability after 2 hpi. Results suggest that capacitation pathways can be regulated by suitable treatments making the ejaculated sperm able to reach capacitation and fertilize oocytes in similar levels than epididymal spermatozoa, although most of the studied capacitation-associated changes do not correlate with this ability.

  18. Emissions from Electronic Cigarettes: Key Parameters Affecting the Release of Harmful Chemicals.

    PubMed

    Sleiman, Mohamad; Logue, Jennifer M; Montesinos, V Nahuel; Russell, Marion L; Litter, Marta I; Gundel, Lara A; Destaillats, Hugo

    2016-09-01

    Use of electronic cigarettes has grown exponentially over the past few years, raising concerns about harmful emissions. This study quantified potentially toxic compounds in the vapor and identified key parameters affecting emissions. Six principal constituents in three different refill "e-liquids" were propylene glycol (PG), glycerin, nicotine, ethanol, acetol, and propylene oxide. The latter, with mass concentrations of 0.4-0.6%, is a possible carcinogen and respiratory irritant. Aerosols generated with vaporizers contained up to 31 compounds, including nicotine, nicotyrine, formaldehyde, acetaldehyde, glycidol, acrolein, acetol, and diacetyl. Glycidol is a probable carcinogen not previously identified in the vapor, and acrolein is a powerful irritant. Emission rates ranged from tens to thousands of nanograms of toxicants per milligram of e-liquid vaporized, and they were significantly higher for a single-coil vs a double-coil vaporizer (by up to an order of magnitude for aldehydes). By increasing the voltage applied to a single-coil device from 3.3 to 4.8 V, the mass of e-liquid consumed doubled from 3.7 to 7.5 mg puff(-1) and the total aldehyde emission rates tripled from 53 to 165 μg puff(-1), with acrolein rates growing by a factor of 10. Aldehyde emissions increased by more than 60% after the device was reused several times, likely due to the buildup of polymerization byproducts that degraded upon heating. These findings suggest that thermal degradation byproducts are formed during vapor generation. Glycidol and acrolein were primarily produced by glycerin degradation. Acetol and 2-propen-1-ol were produced mostly from PG, while other compounds (e.g., formaldehyde) originated from both. Because emissions originate from reaction of the most common e-liquid constituents (solvents), harmful emissions are expected to be ubiquitous when e-cigarette vapor is present. PMID:27461870

  19. Key parameters affecting the initial leaky effect of hemoglobin-loaded nanoparticles as blood substitutes.

    PubMed

    Zhang, Xiaolan; Liu, Changsheng; Yuan, Yuan; Zhang, Shiyu; Shan, Xiaoqian; Sheng, Yan; Xu, Feng

    2008-06-01

    In order to realize long-term carrying/delivering oxygen and minimize the adverse effects of free hemoglobin (Hb) in vivo, Hb is desired to be confined in Hb-loaded nanoparticles (HbP), a novel blood substitute with potential clinical applications, and thus functions as the native red blood cells (RBCs). However, the initial burst release of Hb ("leaky effect") greatly underscores the significance of this work. The study described here wants to disclose the key preparative parameters, including polymer, excipients in the inner aqueous phase and solvent profile, affecting the Hb release behavior (the initial 24 h) from HbP fabricated by commonly used solvent diffusion/evaporation double emulsion technique. The results demonstrate that PEGlytated polymers, regardless of two- or tri-block copolymers show slower release compared with the corresponding non-PEGlytated ones. The higher polymer concentration yields lower initial release. PEG200, added as excipient facilitates Hb burst effect to about 38.4%, almost 17% increase compared to the control ( approximately 21%), whereas, PVA and Poloxamer188, due to amphiphilic nature, can effectively attenuate this leakage to about 13.0 and 5.1%, respectively. The diffusion/extraction rate from oil phase and the subsequent evaporation rate from the aqueous continuous phase of solvents impose different influences on Hb release. To reduce the burst effect, the initial diffusion/extraction rate should be slow, whereas, the concomitant evaporation rate should be as fast as possible. The results obtained here will be guidance's for the future tailored design of more desirable polymersome nanoparticle blood substitutes.

  20. Emissions from Electronic Cigarettes: Key Parameters Affecting the Release of Harmful Chemicals.

    PubMed

    Sleiman, Mohamad; Logue, Jennifer M; Montesinos, V Nahuel; Russell, Marion L; Litter, Marta I; Gundel, Lara A; Destaillats, Hugo

    2016-09-01

    Use of electronic cigarettes has grown exponentially over the past few years, raising concerns about harmful emissions. This study quantified potentially toxic compounds in the vapor and identified key parameters affecting emissions. Six principal constituents in three different refill "e-liquids" were propylene glycol (PG), glycerin, nicotine, ethanol, acetol, and propylene oxide. The latter, with mass concentrations of 0.4-0.6%, is a possible carcinogen and respiratory irritant. Aerosols generated with vaporizers contained up to 31 compounds, including nicotine, nicotyrine, formaldehyde, acetaldehyde, glycidol, acrolein, acetol, and diacetyl. Glycidol is a probable carcinogen not previously identified in the vapor, and acrolein is a powerful irritant. Emission rates ranged from tens to thousands of nanograms of toxicants per milligram of e-liquid vaporized, and they were significantly higher for a single-coil vs a double-coil vaporizer (by up to an order of magnitude for aldehydes). By increasing the voltage applied to a single-coil device from 3.3 to 4.8 V, the mass of e-liquid consumed doubled from 3.7 to 7.5 mg puff(-1) and the total aldehyde emission rates tripled from 53 to 165 μg puff(-1), with acrolein rates growing by a factor of 10. Aldehyde emissions increased by more than 60% after the device was reused several times, likely due to the buildup of polymerization byproducts that degraded upon heating. These findings suggest that thermal degradation byproducts are formed during vapor generation. Glycidol and acrolein were primarily produced by glycerin degradation. Acetol and 2-propen-1-ol were produced mostly from PG, while other compounds (e.g., formaldehyde) originated from both. Because emissions originate from reaction of the most common e-liquid constituents (solvents), harmful emissions are expected to be ubiquitous when e-cigarette vapor is present.

  1. Parameters Affecting Spore Recovery from Wipes Used in Biological Surface Sampling ▿ †

    PubMed Central

    Da Silva, Sandra M.; Filliben, James J.; Morrow, Jayne B.

    2011-01-01

    The need for the precise and reliable collection of potential biothreat contaminants has motivated research in developing a better understanding of the variability in biological surface sampling methods. In this context, the objective of this work was to determine parameters affecting the efficiency of extracting Bacillus anthracis Sterne spores from commonly used wipe sampling materials and to describe performance using the interfacial energy concept. In addition, surface thermodynamics was applied to understand and predict surface sampling performance. Wipe materials were directly inoculated with known concentrations of B. anthracis spores and placed into extraction solutions, followed by sonication or vortexing. Experimental factors investigated included wipe material (polyester, cotton, and polyester-rayon), extraction solution (sterile deionized water [H2O], deionized water with 0.04% Tween 80 [H2O-T], phosphate-buffered saline [PBS], and PBS with 0.04% Tween 80 [PBST]), and physical dissociation method (vortexing or sonication). The most efficient extraction from wipes was observed for solutions containing the nonionic surfactant Tween 80. The increase in extraction efficiency due to surfactant addition was attributed to an attractive interfacial energy between Tween 80 and the centrifuge tube wall, which prevented spore adhesion. Extraction solution significantly impacted the extraction efficiency, as determined by statistical analysis (P < 0.05). Moreover, the extraction solution was the most important factor in extraction performance, followed by the wipe material. Polyester-rayon was the most efficient wipe material for releasing spores into solution by rank; however, no statistically significant difference between polyester-rayon and cotton was observed (P > 0.05). Vortexing provided higher spore recovery in H2O and H2O-T than sonication, when all three wipe materials and the reference control were considered (P < 0.05). PMID:21296945

  2. Qualitative Parameters of the Colonic Flora in Patients with HNF1A-MODY Are Different from Those Observed in Type 2 Diabetes Mellitus

    PubMed Central

    Mrozinska, Sandra; Radkowski, Piotr; Gosiewski, Tomasz; Szopa, Magdalena; Bulanda, Malgorzata; Ludwig-Galezowska, Agnieszka H.; Morawska, Iwona; Sroka-Oleksiak, Agnieszka; Matejko, Bartlomiej; Kapusta, Przemyslaw; Salamon, Dominika; Malecki, Maciej T.; Wolkow, Pawel

    2016-01-01

    Background. Type 2 diabetes mellitus (T2DM) is determined by genetic and environmental factors. There have been many studies on the relationship between the composition of the gastrointestinal bacterial flora, T2DM, and obesity. There are no data, however, on the gut microbiome structure in monogenic forms of the disease including Maturity Onset Diabetes of the Young (MODY). Methods. The aim of the investigation was to compare the qualitative parameters of the colonic flora in patients with HNF1A-MODY and T2DM and healthy individuals. 16S sequencing of bacterial DNA isolated from the collected fecal samples using the MiSeq platform was performed. Results. There were significant between-group differences in the bacterial profile. At the phylum level, the amount of Proteobacteria was higher (p = 0.0006) and the amount of Bacteroidetes was lower (p = 0.0005) in T2DM group in comparison to the control group. In HNF1A-MODY group, the frequency of Bacteroidetes was lower than in the control group (p = 0.0143). At the order level, Turicibacterales was more abundant in HNF1A-MODY group than in T2DM group. Conclusions. It appears that there are differences in the gut microbiome composition between patients with HNF1A-MODY and type 2 diabetes. Further investigation on this matter should be conducted. PMID:27807544

  3. Population risk and physiological rate parameters for colon cancer. The union of an explicit model for carcinogenesis with the public health records of the United States.

    PubMed

    Herrero-Jimenez, P; Tomita-Mitchell, A; Furth, E E; Morgenthaler, S; Thilly, W G

    2000-01-17

    The relationship between the molecular mechanisms of mutagenesis and the actual processes by which most people get cancer is still poorly understood. One missing link is a physiologically based but quantitative model uniting the processes of mutation, cell growth and turnover. Any useful model must also account for human heterogeneity for inherited traits and environmental experiences. Such a coherent algebraic model for the age-specific incidence of cancer has been developing over the past 50 years. This development has been spurred primarily by the efforts of Nordling [N.O. Nordling, A new theory on the cancer-inducing mechanism, Br. J. Cancer 7 (1953) 68-72], Armitage and Doll [P. Armitage, R. Doll, The age distribution of cancer and a multi-stage theory of carcinogenesis, Br. J. Cancer 8 (1) (1954) 1-12; P. Armitage, R. Doll, A two-stage theory of carcinogenesis in relation to the age distribution of human cancer, Br. J. Cancer 9 (2) (1957) 161-169], and Moolgavkar and Knudson [S.H. Moolgavkar, A.G. Knudson Jr., Mutation and cancer: a model for human carcinogenesis. JNCI 66 (6) (1981) 1037-1052], whose work defined two rate-limiting stages identified with initiation and promotion stages in experimental carcinogenesis. Unfinished in these efforts was an accounting of population heterogeneity and a complete description of growth and genetic change during the growth of adenomas. In an attempt to complete a unified model, we present herein the first means to explicitly compute the essential parameters of the two-stage initiation-promotion model using colon cancer as an example. With public records from the 1930s to the present day, we first calculate the fraction at primary risk for each birth year cohort and note historical changes. We then calculate the product of rates for n initiation-mutations, the product of rates for m promotion-mutations and the average growth rate of the intermediate adenomatous colonies from which colon carcinomas arise. We find that the

  4. Intestinal Epithelial Toll-Like Receptor 4 Signaling Affects Epithelial Function and Colonic Microbiota and Promotes a Risk for Transmissible Colitis

    PubMed Central

    Dheer, Rishu; Santaolalla, Rebeca; Davies, Julie M.; Lang, Jessica K.; Phillips, Matthew C.; Pastorini, Cristhine; Vazquez-Pertejo, Maria T.

    2016-01-01

    Evidence obtained from gene knockout studies supports the role of Toll-like receptor 4 (TLR4) in intestinal inflammation and microbiota recognition. Increased epithelial TLR4 expression is observed in patients with inflammatory bowel disease. However, little is known of the effect of increased TLR4 signaling on intestinal homeostasis. Here, we examined the effect of increased TLR4 signaling on epithelial function and microbiota by using transgenic villin-TLR4 mice that overexpress TLR4 in the intestinal epithelium. Our results revealed that villin-TLR4 mice are characterized by increases in the density of mucosa-associated bacteria and bacterial translocation. Furthermore, increased epithelial TLR4 signaling was associated with an impaired epithelial barrier, altered expression of antimicrobial peptide genes, and altered epithelial cell differentiation. The composition of the colonic luminal and mucosa-associated microbiota differed between villin-TLR4 and wild-type (WT) littermates. Interestingly, WT mice cohoused with villin-TLR4 mice displayed greater susceptibility to acute colitis than singly housed WT mice did. The results of this study suggest that epithelial TLR4 expression shapes the microbiota and affects the functional properties of the epithelium. The changes in the microbiota induced by increased epithelial TLR4 signaling are transmissible and exacerbate dextran sodium sulfate-induced colitis. Together, our findings imply that host innate immune signaling can modulate intestinal bacteria and ultimately the host's susceptibility to colitis. PMID:26755160

  5. Soil moisture affects fatty acids and oil quality parameters in peanut

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drought affects yield of peanut, but its effect on oleic and linoleic acids that influence its oil quality of peanut genotypes with different levels of drought resistance has not been clearly investigated. Therefore, the aims of this research were to determine whether soil water levels could affect...

  6. Stability of Intercellular Exchange of Biochemical Substances Affected by Variability of Environmental Parameters

    NASA Astrophysics Data System (ADS)

    Mihailović, Dragutin T.; Budinčević, Mirko; Balaž, Igor; Mihailović, Anja

    Communication between cells is realized by exchange of biochemical substances. Due to internal organization of living systems and variability of external parameters, the exchange is heavily influenced by perturbations of various parameters at almost all stages of the process. Since communication is one of essential processes for functioning of living systems it is of interest to investigate conditions for its stability. Using previously developed simplified model of bacterial communication in a form of coupled difference logistic equations we investigate stability of exchange of signaling molecules under variability of internal and external parameters.

  7. Sensitivity Analysis of Parameters Affecting Protection of Water Resources at Hanford WA

    SciTech Connect

    DAVIS, J.D.

    2002-02-08

    The scope of this analysis was to assess the sensitivity of contaminant fluxes from the vadose zone to the water table, to several parameters, some of which can be controlled by operational considerations.

  8. Physical Parameters Affecting the Emanation of RADON-222 from Coal Ash.

    NASA Astrophysics Data System (ADS)

    Barton, Terence Patrick

    The Rn-222 emanation coefficients for coal ash and parameters which affected them were measured. Samples of ash from both stoker fired and pulverized coal fired boilers were obtained. The stoker ash samples were mechanically separated into size fractions. The pulverized samples were too fine for mechanical sizing and were categorized qualitatively according to origin. Bulk density of the stoker fractions was measured and ranged from .488 to .944 g-cm('-3), increasing as a function of decreasing particle size. Bulk density of the pulverized ash ranged from 1.254 to 1.520 g-cm('-3). Specific gravity of the stoker fractions ranged from 2.017 to 2.390 g-cm('-3), also increasing as a function of decreasing particle size. Specific gravity of the pulverized ash ranged from 2.357 to 2.588 g-cm(' -3). Ra-226 content of the samples was determined by gamma spectrometric analysis of the 352-KeV gamma of Pb -214 and the 609-KeV gamma of Bi-214 from sealed samples of ash. Ra-226 concentrations in the stoker fractions ranged from 11.82 to 16.77 dpm-g('-1), increasing as a function of decreasing particle size. Ra-226 concentrations in the pulverized ash ranged from 6.44 to 7.59 dpm-g(' -1). Scintillation cells were constructed out of commonly available materials and a commercial preparation of ZnS(Ag) scintillator. Emanation chambers which allowed for moderately large sample masses were constructed. The procedure used to measure emanation coefficients was shown to be insensitive to ingrowth time at greater than 3 days ingrowth and relatively insensitive to variations in sample porosity. Emanation coefficients of the stoker fractions were measured at moisture contents of 0, 1.0, 10, 20, and 40 percent by weight. Within each size fraction the emanation coefficient increased as a function of moisture content, ranging from 9.58 x 10('-4) to 4.13 x 10('-2) between 0 and 20 percent moisture, respectively. Emanation coefficients also increased as a function of decreasing particle size

  9. Fungal infection of the colon

    PubMed Central

    Praneenararat, Surat

    2014-01-01

    Fungi are pathogens that commonly infect immunocompromised patients and can affect any organs of the body, including the colon. However, the literature provides limited details on colonic infections caused by fungi. This article is an intensive review of information available on the fungi that can cause colon infections. It uses a comparative style so that its conclusions may be accessible for clinical application. PMID:25364269

  10. Deviations of Lambert-Beer's law affect corneal refractive parameters after refractive surgery.

    PubMed

    Jiménez, José R; Rodríguez-Marín, Francisco; Anera, Rosario G; Jiménez Del Barco, Luis

    2006-06-12

    We calculate whether deviations of Lambert-Beer's law, which regulates depth ablation during corneal ablation, significantly influence corneal refractive parameters after refractive surgery and whether they influence visual performance. For this, we compute a point-to-point correction on the cornea while assuming a non-linear (including a quadratic term) fit for depth ablation. Post-surgical equations for refractive parameters using a non-linear fit show significant differences with respect to parameters obtained from a linear fit (Lambert-Beer's law). Differences were also significant for corneal aberrations. These results show that corneal-ablation algorithms should include analytical information on deviations from Lambert-Beer's law for achieving an accurate eye correction.

  11. Plunger Kinematic Parameters Affecting Quality of High-Pressure Die-Cast Aluminum Alloys

    NASA Astrophysics Data System (ADS)

    Fiorese, Elena; Bonollo, Franco

    2016-07-01

    The selection of the optimal process parameters in high-pressure die casting has been long recognized as a complex problem due to the involvement of a large number of interconnected variables. Among these variables, the effect of the plunger motion has been proved to play a prominent role, even if a thorough and exhaustive study is still missing in the literature. To overcome this gap, this work aims at identifying the most relevant plunger kinematic parameters and estimates their correlation with the casting quality, by means of a statistically significant sample manufactured with different plunger motion profiles. In particular, slow and fast shot velocities and switching position between two stages have been varied randomly in accordance with design of experiment methodology. The quality has been assessed through the static mechanical properties and porosity percentage. As a further proof, the percentage of oxides has been estimated on the fracture surfaces. These measurements have been correlated to novel parameters, representing the mechanical energy and the inertial force related to the plunger motion, that have been extracted from the time-history of the displacement curves. The application of statistical methods demonstrates that these novel parameters accurately explain and predict the overall quality of castings.

  12. Sensitivity studies on parameters affecting gas release from an underground rock cavern

    SciTech Connect

    Schlueter, E.; Pruess, K.

    1990-01-01

    A series of numerical simulation experiments is performed to quantify the effects of the release and migration of non-condensible gas in water-saturated fractured rock formations. The relative importance of multiphase parameters such as relative permeability, capillary pressure, intrinsic permeability, and porosity on system behavior is studied. 10 refs., 28 figs., 5 tabs.

  13. Investigation of parameters affecting treatment time in MRI-guided transurethral ultrasound therapy

    NASA Astrophysics Data System (ADS)

    N'Djin, W. A.; Burtnyk, M.; Chopra, R.; Bronskill, M. J.

    2010-03-01

    MRI-guided transurethral ultrasound therapy shows promise for minimally invasive treatment of localized prostate cancer. Real-time MR temperature feedback enables the 3D control of thermal therapy to define an accurate region within the prostate. Previous in-vivo canine studies showed the feasibility of this method using transurethral planar transducers. The aim of this simulation study was to reduce the procedure time, while maintaining treatment accuracy by investigating new combinations of treatment parameters. A numerical model was used to simulate a multi-element heating applicator rotating inside the urethra in 10 human prostates. Acoustic power and rotation rate were varied based on the feedback of the temperature in the prostate. Several parameters were investigated for improving the treatment time. Maximum acoustic power and rotation rate were optimized interdependently as a function of prostate radius and transducer operating frequency, while avoiding temperatures >90° C in the prostate. Other trials were performed on each parameter separately, with the other parameter fixed. The concept of using dual-frequency transducers was studied, using the fundamental frequency or the 3rd harmonic component depending on the prostate radius. The maximum acoustic power which could be used decreased as a function of the prostate radius and the frequency. Decreasing the frequency (9.7-3.0 MHz) or increasing the power (10-20 W.cm-2) led to treatment times shorter by up to 50% under appropriate conditions. Dual-frequency configurations, while helpful, tended to have less impact on treatment times. Treatment accuracy was maintained and critical adjacent tissues like the rectal wall remained protected. The interdependence between power and frequency may require integrating multi-parametric functions inside the controller for future optimizations. As a first approach, however, even slight modifications of key parameters can be sufficient to reduce treatment time.

  14. Apramycin treatment affects selection and spread of a multidrug-resistant Escherichia coli strain able to colonize the human gut in the intestinal microbiota of pigs.

    PubMed

    Herrero-Fresno, Ana; Zachariasen, Camilla; Hansen, Monica Hegstad; Nielsen, Alexander; Hendriksen, Rene S; Nielsen, Søren Saxmose; Olsen, John Elmerdahl

    2016-01-07

    The effect of apramycin treatment on transfer and selection of an Escherichia coli strain (E. coli 912) in the intestine of pigs was analyzed through an in vivo experiment. The strain was sequenced and assigned to the sequence type ST101 and serotype O11. It carried resistance genes to apramycin/gentamicin, sulphonamide, tetracycline, hygromycin B, β-lactams and streptomycin [aac(3)-IV, sul2, tet(X), aph(4), bla TEM-1 and strA/B], with all but tet(X) located on the same conjugative plasmid. Nineteen pigs were randomly allocated into two inoculation groups, one treated with apramycin (pen 2) and one non-treated (pen 3), along with a non-inoculated control group (pen 1). Two pigs of pen 2 and 3 were inoculated intragastrically with a rifampicin resistant variant of the strain. Apramycin treatment in pen 2 was initiated immediately after inoculation. Strain colonization was assessed in the feces from all pigs. E. coli 912 was shown to spread to non-inoculated pigs in both groups. The selective effect did not persist beyond 3 days post-treatment, and the strain was not detected from this time point in pen 2. We demonstrated that E. coli 912 was able to spread between pigs in the same pen irrespective of treatment, and apramycin treatment resulted in significantly higher counts compared to the non-treated group. This represents the first demonstration of how antimicrobial treatment affects spread of resistant bacteria in pig production. The use of apramycin may lead to enhanced spread of gentamicin-resistant E. coli. Since gentamicin is a first-choice drug for human bacteremia, this is of concern.

  15. Metastatic Colonization

    PubMed Central

    Massagué, Joan; Obenauf, Anna C.

    2016-01-01

    Metastasis is the main cause of death from cancer. To colonize distant organs, circulating cancer cells must overcome many obstacles through mechanisms that we are starting to understand. Infiltrating distant tissue, evading immune defences, adapting to supportive niches, surviving as latent tumour-initiating seeds, and eventually breaking out to replace the host tissue, are key steps for metastatic colonization. These obstacles make metastasis a highly inefficient process, but once metastases are established current treatments frequently fail to provide durable responses. A better understanding of the mechanistic determinants of metastatic colonization is needed to better prevent and treat metastatic cancer. PMID:26791720

  16. Refining in silico simulation to study digestion parameters affecting the bioaccessibility of lipophilic nutrients and micronutrients.

    PubMed

    Marze, Sébastien

    2015-01-01

    Despite the considerable number of in vivo and in vitro studies on the digestive fate of lipophilic nutrients, micronutrients, and bioactives, the effects of the structure and composition of foods on the physicochemical mechanisms of luminal digestion are still poorly understood. Studying them is indeed complex because the number of parameters is high and many of them are interdependent. To solve this problem, an in silico simulation based on a multi-agent system was recently proposed to study the intestinal bioaccessibility of lipophilic nutrients and micronutrients from a single oil droplet. The roles of lipolysis and solubilization in bile salt were included. The effects of several food and digestion parameters were in line with those reported in the experimental literature. The goal of the research reported in this new article was to include more digestion parameters in the simulation in order to make it more realistic against complex cases. This was done in one specific digestion condition reflecting in vitro experiments, using droplets of tricaprylin or triolein containing vitamin A. The structure and principles of the original model were kept, with independent local modifications in order to study each factor separately. First, a gastric step was added where lipolysis took place, and only a marginal effect on the following intestinal step was found. Then, the chemical form of vitamin A, either non-hydrolyzed retinyl ester or retinyl ester instantly hydrolyzed into retinol, was investigated by considering different localizations in the droplet, resulting in a higher bioaccessibility for the retinol. The case of a mixture of tricaprylin and triolein indicated an influence of the oil phase viscosity. The consideration of mixed micelles compared to simple bile salt micelles was also investigated, and resulted in a higher vitamin A bioaccessibility, especially with triolein. Finally, a full model including the most influential parameters was tested to simulate

  17. Experimental Parameters Affecting Stripping of Rare Earth Elements from Loaded Sorptive Media in Simulated Geothermal Brines

    DOE Data Explorer

    Dean Stull

    2016-05-24

    Experimental results from several studies exploring the impact of pH and acid volume on the stripping of rare earth elements (REEs) loaded onto ligand-based media via an active column. The REEs in this experiment were loaded onto the media through exposure to a simulated geothermal brine with known mineral concentrations. The data include the experiment results, rare earth element concentrations, and the experimental parameters varied.

  18. Motion coordination affects movement parameters in a joint pick-and-place task.

    PubMed

    Vesper, Cordula; Soutschek, Alexander; Schubo, Anna

    2009-12-01

    This study examined influences of social context on movement parameters in a pick-and-place task. Participants' motion trajectories were recorded while they performed sequences of natural movements either working side-by-side with a partner or alone. It was expected that movement parameters would be specifically adapted to the joint condition to overcome the difficulties arising from the requirement to coordinate with another person. To disentangle effects based on participants' effort to coordinate their movements from effects merely due to the other's presence, a condition was included where only one person performed the task while being observed by the partner. Results indicate that participants adapted their movements temporally and spatially to the joint action situation: Overall movement duration was shorter, and mean and maximum velocity was higher when actually working together than when working alone. Pick-to-place trajectories were also shifted away from the partner in spatial coordinates. The partner's presence as such did not have an impact on movement parameters. These findings are interpreted as evidence for the use of implicit strategies to facilitate movement coordination in joint action tasks.

  19. Coated or doped carbon nanotube network sensors as affected by environmental parameters

    NASA Technical Reports Server (NTRS)

    Li, Jing (Inventor)

    2011-01-01

    Methods for using modified single wall carbon nanotubes ("SWCNTs") to detect presence and/or concentration of a gas component, such as a halogen (e.g., Cl.sub.2), hydrogen halides (e.g., HCl), a hydrocarbon (e.g., C.sub.nH.sub.2n+2), an alcohol, an aldehyde or a ketone, to which an unmodified SWCNT is substantially non-reactive. In a first embodiment, a connected network of SWCNTs is coated with a selected polymer, such as chlorosulfonated polyethylene, hydroxypropyl cellulose, polystyrene and/or polyvinylalcohol, and change in an electrical parameter or response value (e.g., conductance, current, voltage difference or resistance) of the coated versus uncoated SWCNT networks is analyzed. In a second embodiment, the network is doped with a transition element, such as Pd, Pt, Rh, Ir, Ru, Os and/or Au, and change in an electrical parameter value is again analyzed. The parameter change value depends monotonically, not necessarily linearly, upon concentration of the gas component. Two general algorithms are presented for estimating concentration value(s), or upper or lower concentration bounds on such values, from measured differences of response values.

  20. Retrospective surveillance of metabolic parameters affecting reproductive performance of Japanese Black breeding cows

    PubMed Central

    Watanabe, Urara; Yamato, Osamu; Otoi, Takeshige; Okamoto, Koji

    2014-01-01

    This retrospective study was conducted to confirm the relationship between pre- and postpartum metabolic parameters and postpartum reproductive performance and to clarify seasonal characteristics of the metabolic parameters by using our metabolic profile test (MPT) database of Japanese Black breeding herds. In evaluation 1, MPT databases of blood samples from multiparous cows collected prepartum and postpartum were divided into two groups according to calving interval, and each MPT parameter was compared. In evaluation 2, the same MPT databases used in evaluation 1 were divided into two groups according to the sampling period. Significant differences were found in the prepartal total protein and postpartal γ-glutamyltransferase in evaluation 1. In evaluation 2, significant differences were found in the prepartal and postpartal total protein, albumin/globulin ratio, and glucose. Clear seasonal differences in MPT results emphasized the usefulness of the MPT in breeding cattle herds fed home-pasture roughage and suggest that unsatisfactory reproductive performance during hot periods reflects inadequate nutritional content of the diet and possible reduced feed intake due to heat stress. PMID:24675835

  1. Parameters Affecting Image-guided, Hydrodynamic Gene Delivery to Swine Liver

    PubMed Central

    Kamimura, Kenya; Suda, Takeshi; Zhang, Guisheng; Aoyagi, Yutaka; Liu, Dexi

    2013-01-01

    Development of a safe and effective method for gene delivery to hepatocytes is a critical step toward gene therapy for liver diseases. Here, we assessed the parameters for gene delivery to the livers of large animals (pigs, 40–65 kg) using an image-guided hydrodynamics-based procedure that involves image-guided catheter insertion into the lobular hepatic vein and hydrodynamic injection of reporter plasmids using a computer-controlled injector. We demonstrated that injection parameters (relative position of the catheter in the hepatic vasculature, intravascular pressure upon injection, and injection volume) are directly related to the safety and efficiency of the procedure. By optimizing these parameters, we explored for the first time, the advantage of the procedure for sequential injections to multiple lobes in human-sized pigs. The optimized procedure resulted in sustained expression of the human α-1 antitrypsin gene in livers for more than 2 months after gene delivery. In addition, repeated hydrodynamic gene delivery was safely conducted and no adverse events were seen in the entire period of the study. Our results support the clinical applicability of the image-guided hydrodynamic gene delivery method for the treatment of liver diseases. PMID:24129227

  2. Parameters affecting drug release from inert matrices. 1: Monte Carlo simulation.

    PubMed

    Villalobos, Rafael; Viquez, Hugo; Hernández, Beatriz; Ganem, Adriana; Melgoza, Luz María; Young, Paul M

    2012-01-01

    This study investigates the use of Monte Carlo simulation for the determination of release properties from cubic inert matrices. Specifically, the study has focused on factors including porosity, surface area and tortuosity. The release platform was formed by simulating matrices with different ratios of drug and excipient, which undergo drug release in a uni-directional (two-face) or omni-directional (six-face) process. Upon completion of each simulation the matrix 'carcass' was examined and porosity and tortuosity of the medium evaluated. The tortuosity of the medium was evaluated directly by a blind random walk algorithm. These parameters as well as the release profile were then studied with respect to common mathematical models describing drug diffusion (the square-root, power and Weibull models). It was found that, depending on their composition, the matrices systems were either homogeneous or heterogeneous in nature. Furthermore, it was found that the physical parameters could be successfully fitted to the a and b constants of the Weibull model. This approach allows the prediction of drug release from an inert matrix system with the knowledge of a few physical parameters.

  3. Treatment parameters affecting the response of normal brain to photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Chen, Qun; Chopp, Michael; Dereski, Mary O.; Wilson, Brian C.; Patterson, Michael S.; Kessel, David; Heads, Larry; Hetzel, Fred W.

    1993-06-01

    Different aspects of photodynamic therapy in normal rat brain tissue have been studied, in an effort to understand and improve the dosimetry of this new modality in treatment of brain tumors. dosimetry parameters, including light energy dose, fluence rate and beam size, and drug dosage were studied. PDT induced lesion depth in brain was measured as a biological endpoint. Effective attenuation depth and absolute light fluence rate distribution under superficial irradiation were measured using invasive optical probes. Photosensitizer uptake was quantified using HPLC analysis. The results indicate that normal brain have a high intrinsic sensitivity to PDT treatment, based on the estimated photodynamic threshold.

  4. Cadmium toxicity for terrestrial invertebrates: taking soil parameters affecting bioavailability into account.

    PubMed

    Lock, K; Janssen, C R

    2001-10-01

    Acute and chronic ecotoxicity tests with cadmium were conducted with the earthworm Eisenia fetida, the potworm Enchytraeus albidus and the springtail Folsomia candida. To assess the influence of the soil type on cadmium bioavailability, these tests were carried out in a standard artificial soil, in a sandy and a loamy field soil. It was not possible to evaluate the influence of soil parameters on the bioavailability on the basis of the experiments that were conducted in only three different soil types, therefore, literature data were also included. However, even in the same standard artificial soils, toxicity data in the literature for Eisenia fetida and Folsomia candida varied considerably. Consequently, no models could be developed that allow a normalization of the ecotoxicity of cadmium to parameters controlling bioavailability. In contrast to zinc, effect concentrations of cadmium for terrestrial invertebrates were always much higher than background concentrations. As the effect of aging on the bioavailability of cadmium was never taken into account, because toxicity experiments were always carried out in freshly spiked soilds, these effect concentrations may even be regarded as conservative. Furthermore, the zinc-cadmium ratio in soils is usually so high that the risk of zinc ecotoxicity for terrestrial invertebrates will usually be much greater in comparison to cadmium ecotoxicity. PMID:11556119

  5. Does Body Mass Index in Pregnant Women Affect Laboratory Parameters in the Newborn?

    PubMed Central

    Raguž, Marjana Jerković; Brzica, Jerko

    2016-01-01

    Objective The objective of this study was to determine the effect of body mass index (BMI) during pregnancy in laboratory parameters in the serum of the three groups of pregnant women and in their newborns. Methods This prospective study is comparison between the three groups of pregnant women and their newborns categorized according to their BMI. The study included 128 pregnant women and their newborns. In this study, the concentration of blood count, iron, ferritin, and bilirubin were analyzed in the subjects. Results The pregnant women in the three groups significantly differ in the values of blood count (p < 0.001). Statistically significant difference in iron and ferritin was not found between individual three studied groups of pregnant women (p = 0.947). The newborn of the first group of pregnant women had significantly lower values of ferritin (p < 0.001), leucocytes (p < 0.001), and bilirubin (p < 0.001). Significant positive correlation between BMI of pregnant women and leucocytes, ferritin, and bilirubin of the newborn was found (p < 0.001). Conclusion In this study, the tested pregnant women do not have biochemical signs of anemia, neither do their newborns. It was noted that there was no negative correlation between individual tested biochemical parameters for anemia in pregnant women and their newborns. PMID:27119047

  6. Cadmium toxicity for terrestrial invertebrates: taking soil parameters affecting bioavailability into account.

    PubMed

    Lock, K; Janssen, C R

    2001-10-01

    Acute and chronic ecotoxicity tests with cadmium were conducted with the earthworm Eisenia fetida, the potworm Enchytraeus albidus and the springtail Folsomia candida. To assess the influence of the soil type on cadmium bioavailability, these tests were carried out in a standard artificial soil, in a sandy and a loamy field soil. It was not possible to evaluate the influence of soil parameters on the bioavailability on the basis of the experiments that were conducted in only three different soil types, therefore, literature data were also included. However, even in the same standard artificial soils, toxicity data in the literature for Eisenia fetida and Folsomia candida varied considerably. Consequently, no models could be developed that allow a normalization of the ecotoxicity of cadmium to parameters controlling bioavailability. In contrast to zinc, effect concentrations of cadmium for terrestrial invertebrates were always much higher than background concentrations. As the effect of aging on the bioavailability of cadmium was never taken into account, because toxicity experiments were always carried out in freshly spiked soilds, these effect concentrations may even be regarded as conservative. Furthermore, the zinc-cadmium ratio in soils is usually so high that the risk of zinc ecotoxicity for terrestrial invertebrates will usually be much greater in comparison to cadmium ecotoxicity.

  7. Administration of thyroxine affects the morphometric parameters and VEGF expression in the uterus and placenta and the uterine vascularization but does not affect reproductive parameters in gilts during early gestation.

    PubMed

    Souza, C A; Ocarino, N M; Silva, J F; Boeloni, J N; Nascimento, E F; Silva, I J; Castro, R D; Moreira, L P; Almeida, F R C L; Chiarini-Garcia, H; Serakides, R

    2011-02-01

    The aim of this study was to evaluate the effects of thyroxine administration on morphometric parameters, expression of vascular endothelial growth factor (VEGF) and vascularization in the uterus and placenta and reproductive parameters in gilts at 70 days of gestation. At 150 days of age, i.e., before first heat, 20 gilts were randomly divided into two experimental groups: treated (n=10) and control (n=10). The treated group received a daily dose of 400 μg of L-thyroxine (T(4)) in their diet until slaughter and the control group received only typical meals. Before artificial insemination, blood was collected to determine plasma total T(4). The gilts were inseminated in the second oestrus and slaughtered at 70 days of gestation. The foetal thyroid follicular epithelium height, number, size and weight of foetuses; foetal myogenesis, corpora lutea number, embryonic mortality rate, uterine weight, placental weight and placental fluid volume were measured. Histomorphometric and immunohistochemical analysis of uterus and placenta were determined. The averages of all variables were compared by the Student's t-test. The gilts treated with thyroxine showed significant increase of plasma total T(4). At 70 days of gestation, the heights of the trophoblastic epithelium, endometrial epithelium and endometrial gland epithelium were significantly higher in the group treated with T(4). The expression of cytoplasmatic and nuclear VEGF in trophoblastic cells and the number of blood vessels per field in endometrial stroma were significantly higher in the gilts treated with T(4). No other significant differences between groups were obtained with respect to other parameters (p>0.05). We conclude that oral administration of T(4) up to 70 days of pregnancy in gilts affects the morphometric parameters, the expression of placental VEGF and the uterine vascularization but does not affect reproductive parameters in gilts during early gestation.

  8. Use of Artificial Neural Networks to Examine Parameters Affecting the Immobilization of Streptokinase in Chitosan

    PubMed Central

    Modaresi, Seyed Mohamad Sadegh; Faramarzi, Mohammad Ali; Soltani, Arash; Baharifar, Hadi; Amani, Amir

    2014-01-01

    Streptokinase is a potent fibrinolytic agent which is widely used in treatment of deep vein thrombosis (DVT), pulmonary embolism (PE) and acute myocardial infarction (MI). Major limitation of this enzyme is its short biological half-life in the blood stream. Our previous report showed that complexing streptokinase with chitosan could be a solution to overcome this limitation. The aim of this research was to establish an artificial neural networks (ANNs) model for identifying main factors influencing the loading efficiency of streptokinase, as an essential parameter determining efficacy of the enzyme. Three variables, namely, chitosan concentration, buffer pH and enzyme concentration were considered as input values and the loading efficiency was used as output. Subsequently, the experimental data were modeled and the model was validated against a set of unseen data. The developed model indicated chitosan concentration as probably the most important factor, having reverse effect on the loading efficiency. PMID:25587327

  9. Analysis of Operational Parameters Affecting the Sulfur Content in Hot Metal of the COREX Process

    NASA Astrophysics Data System (ADS)

    Wu, Shengli; Wang, Laixin; Kou, Mingyin; Wang, Yujue; Zhang, Jiacong

    2016-10-01

    The COREX process, which has obvious advantages in environment protection, still has some disadvantages. It has a higher sulfur content in hot metal (HM) than the blast furnace has. In the present work, the distribution and transfer of sulfur in the COREX have been analyzed and several operational parameters related to the sulfur content in HM ([pct S]) have been obtained. Based on this, the effects of the coal rate, slag ratio, temperature of HM, melting rate, binary basicity (R 2), the ratio of MgO/Al2O3, utilization of reducing gas, top gas consumption per ton burden solid, metallization rate, oxidation degree of reducing gas, and coal and DRI distribution index on the sulfur content in HM are investigated. What's more, a linear model has been developed and subsequently used for predicting and controlling the S content in HM of the COREX process.

  10. A Monte Carlo study of parameters affecting computer simulations of crater saturation density

    NASA Astrophysics Data System (ADS)

    Woronow, A.

    1985-02-01

    Computer models of cratered surfaces often use inputs of uncertain nature and importance. This work evaluates the sensitivity of the resulting crater-saturation estimates to the input parameters, principally applicable to the study of craters upward from 8 km diameter. In order of decreasing importance, crater saturation simulations are found to be sensitive to: (1) the dynamic range of crater diameters used, (2) the effectiveness of ejecta-blanket obliteration assumed, and (3) the number of points taken to describe the crater rim. The size of the largest crater in proportion to the size of the simulated surface has no effect on the results when the edges of the simulated surface are correctly treated and craters are not counted simply by integers. Craters should be counted by their fractions lying within the simulated area. A similar procedure is recommended when gathering crater size-density data from images.

  11. A Monte Carlo study of parameters affecting computer simulations of crater saturation density

    NASA Technical Reports Server (NTRS)

    Woronow, A.

    1985-01-01

    Computer models of cratered surfaces often use inputs of uncertain nature and importance. This work evaluates the sensitivity of the resulting crater-saturation estimates to the input parameters, principally applicable to the study of craters upward from 8 km diameter. In order of decreasing importance, crater saturation simulations are found to be sensitive to: (1) the dynamic range of crater diameters used, (2) the effectiveness of ejecta-blanket obliteration assumed, and (3) the number of points taken to describe the crater rim. The size of the largest crater in proportion to the size of the simulated surface has no effect on the results when the edges of the simulated surface are correctly treated and craters are not counted simply by integers. Craters should be counted by their fractions lying within the simulated area. A similar procedure is recommended when gathering crater size-density data from images.

  12. A systematic experimental investigation of significant parameters affecting model tire hydroplaning

    NASA Technical Reports Server (NTRS)

    Wray, G. A.; Ehrlich, I. R.

    1973-01-01

    The results of a comprehensive parametric study of model and small pneumatic tires operating on a wet surface are presented. Hydroplaning inception (spin down) and rolling restoration (spin up) are discussed. Conclusions indicate that hydroplaning inception occurs at a speed significantly higher than the rolling restoration speed. Hydroplaning speed increases considerably with tread depth, surface roughness and tire inflation pressure of footprint pressure, and only moderately with increased load. Water film thickness affects spin down speed only slightly. Spin down speed varies inversely as approximately the one-sixth power of film thickness. Empirical equations relating tire inflation pressure, normal load, tire diameter and water film thickness have been generated for various tire tread and surface configurations.

  13. Potato Production as Affected by Crop Parameters and Meteoro Logical Elements

    NASA Astrophysics Data System (ADS)

    Pereira, André B.; Villa Nova, Nilson A.; Pereira, Antonio R.

    Meteorological elements directly influence crop potential productivity, regulating its transpiration, photosynthesis, and respiration processes in such a way as to control the growth and development of the plants throughout their physiological mechanisms at a given site. The interaction of the meteorological factors with crop responses is complex and has been the target of attention of many researchers from all over the world. There is currently a great deal of interest in estimating crop productivity as a function of climate by means of different crop weather models in order to help growers choose planting locations and timing to produce high yields with good tuber quality under site-specific atmospheric conditions. In this manuscript an agrometeorological model based on maximum carbon dioxide assimilation rates for C3 plants, fraction of photosynthetically active radiation, air temperature, photoperiod duration, and crop parameters is assessed as to its performance under tropical conditions. Crop parameters include leaf areaand harvest indexes, dry matter content of potato tubers, and crop cycles to estimate potato potential yields. Productivity obtained with the cultivar Itararé, grown with adequate soil water supply conditions at four different sites in the State of São Paulo (Itararé, Piracicaba, TatuÍ, and São Manuel), Brazil, were used to test the model. The results showed thatthe agrometeorological model tested under the climatic conditions of the State of São Paulo in general underestimated irrigated potato yield by less than 10%.This justifies the recommendation to test the performance of the model in study in other climaticregions for different crops and genotypes under optimal irrigationconditions in further scientific investigations. We reached the conclusion that the agrometeorological model taking into account information on leaf area index, photoperiod duration, photosynthetically active radiation and air temperature is feasible to estimate

  14. Fructose and glucose differentially affect aging and carbonyl/oxidative stress parameters in Saccharomyces cerevisiae cells.

    PubMed

    Semchyshyn, Halyna M; Lozinska, Liudmyla M; Miedzobrodzki, Jacek; Lushchak, Volodymyr I

    2011-05-15

    Fructose is commonly used as an industrial sweetener and has been excessively consumed in human diets in the last decades. High fructose intake is causative in the development of metabolic disorders, but the mechanisms underlying fructose-induced disturbances are under debate. Fructose compared to glucose has been found to be a more potent initiator of the glycation reaction. Therefore, we supposed that glucose and fructose might have different vital effects. Here we compare the effects of glucose and fructose on yeast cell viability and markers of carbonyl/oxidative stress. Analysis of the parameters in cells growing on glucose and fructose clearly reveals that yeast growing on fructose has higher levels of carbonyl groups in proteins, α-dicarbonyl compounds and reactive oxygen species. This may explain the observation that fructose-supplemented growth as compared with growth on glucose resulted in more pronounced age-related decline in yeast reproductive ability and higher cell mortality. The results are discussed from the point of view that fructose rather than glucose is more extensively involved in glycation and ROS generation in vivo, yeast aging and development of carbonyl/oxidative stress. It should be noted that carbohydrate restriction used in this study does not reveal a significant difference between markers of aging and carbonyl/oxidative stress in yeasts cultivated on glucose and fructose.

  15. Parameters affecting enzyme-assisted aqueous extraction of extruded sunflower meal.

    PubMed

    Campbell, Kerry A; Vaca-Medina, Guadalupe; Glatz, Charles E; Pontalier, Pierre-Yves

    2016-10-01

    Microscopic observation of sunflower meal before and after extraction indicated that extensive cellular disruption was achieved by extrusion, but that unextracted oil remained sequestered as coalesced oil within the void spaces of disrupted cotyledon cells. A full factorial design experiment was defined to develop aqueous extraction processing (AEP) with and without enzymes to improve vegetable oil extraction yields of extruded sunflower meal. This experimental design studied the influence of four parameters, agitation, liquid/solid (L/S) ratio, and cellulase and protease addition, on extraction yield of lipid and protein. Agitation and addition of cellulases increased oil extraction yield, indicating that emulsification of oil and alteration of the geometry of the confining cellular matrix were important mechanisms for improving yields. Protease and liquid-solid ratio of the extraction mixture did not have significant effects, indicating key differences with previously established soy oil extraction mechanisms. Maximum yields attained for oil and protein extraction were 39% and 90%, respectively, with the aid of a surfactant.

  16. Predictive Blood Chemistry Parameters for Pansteatitis-Affected Mozambique Tilapia (Oreochromis mossambicus).

    PubMed

    Bowden, John A; Cantu, Theresa M; Chapman, Robert W; Somerville, Stephen E; Guillette, Matthew P; Botha, Hannes; Hoffman, Andre; Luus-Powell, Wilmien J; Smit, Willem J; Lebepe, Jeffrey; Myburgh, Jan; Govender, Danny; Tucker, Jonathan; Boggs, Ashley S P; Guillette, Louis J

    2016-01-01

    One of the largest river systems in South Africa, the Olifants River, has experienced significant changes in water quality due to anthropogenic activities. Since 2005, there have been various "outbreaks" of the inflammatory disease pansteatitis in several vertebrate species. Large-scale pansteatitis-related mortality events have decimated the crocodile population at Lake Loskop and decreased the population at Kruger National Park. Most pansteatitis-related diagnoses within the region are conducted post-mortem by either gross pathology or histology. The application of a non-lethal approach to assess the prevalence and pervasiveness of pansteatitis in the Olifants River region would be of great importance for the development of a management plan for this disease. In this study, several plasma-based biomarkers accurately classified pansteatitis in Mozambique tilapia (Oreochromis mossambicus) collected from Lake Loskop using a commercially available benchtop blood chemistry analyzer combined with data interpretation via artificial neural network analysis. According to the model, four blood chemistry parameters (calcium, sodium, total protein and albumin), in combination with total length, diagnose pansteatitis to a predictive accuracy of 92 percent. In addition, several morphometric traits (total length, age, weight) were also associated with pansteatitis. On-going research will focus on further evaluating the use of blood chemistry to classify pansteatitis across different species, trophic levels, and within different sites along the Olifants River. PMID:27115488

  17. Does aerobic exercise intensity affect health-related parameters in overweight women?

    PubMed

    Botero, João P; Prado, Wagner L; Guerra, Ricardo L F; Speretta, Guilherme F F; Leite, Richard D; Prestes, Jonato; Sanz, Adrián V; Lyons, Scott; de Azevedo, Paulo H S M; Baldissera, Vilmar; Perez, Sergio E A; Dâmaso, Ana; da Silva, Rozinaldo G

    2014-03-01

    The aim of this study was to compare the effect of a cycling training programme performed at intensity corresponding to the lowest value of the respiratory quotient (RQ) versus at intensity corresponding to the ventilatory threshold (VT), on body composition and health-related parameters in overweight women. Thirty-two sedentary obese women (27-42 years old) were studied in a randomized trial of either RQ (n = 17) or VT (n = 15). RQ and VT training sessions were equalized by time (60 min) and performed in a cycloergometer. Anthropometry, body composition, lipid profile, glucose, basal metabolic rate (BMR) and fitness (maximal oxygen uptake) were evaluated before and after 12 weeks of intervention. Body weight, body mass index, fatness and fitness were improved in both groups (P<0·001). Triglycerides (TG) levels decreased only in response to RQ (P<0·001) and fat-free mass (FFM) to VT (P = 0·002). No differences were observed between groups. Both exercise intensities seem to be effective for improving health in overweight women. However, low-intensity compared with the high-intensity exercise training appears to have additional benefits on TG levels and to maintenance of FFM.

  18. Predictive Blood Chemistry Parameters for Pansteatitis-Affected Mozambique Tilapia (Oreochromis mossambicus)

    PubMed Central

    Chapman, Robert W.; Somerville, Stephen E.; Guillette, Matthew P.; Botha, Hannes; Hoffman, Andre; Luus-Powell, Wilmien J.; Smit, Willem J.; Lebepe, Jeffrey; Myburgh, Jan; Govender, Danny; Tucker, Jonathan; Boggs, Ashley S. P.

    2016-01-01

    One of the largest river systems in South Africa, the Olifants River, has experienced significant changes in water quality due to anthropogenic activities. Since 2005, there have been various “outbreaks” of the inflammatory disease pansteatitis in several vertebrate species. Large-scale pansteatitis-related mortality events have decimated the crocodile population at Lake Loskop and decreased the population at Kruger National Park. Most pansteatitis-related diagnoses within the region are conducted post-mortem by either gross pathology or histology. The application of a non-lethal approach to assess the prevalence and pervasiveness of pansteatitis in the Olifants River region would be of great importance for the development of a management plan for this disease. In this study, several plasma-based biomarkers accurately classified pansteatitis in Mozambique tilapia (Oreochromis mossambicus) collected from Lake Loskop using a commercially available benchtop blood chemistry analyzer combined with data interpretation via artificial neural network analysis. According to the model, four blood chemistry parameters (calcium, sodium, total protein and albumin), in combination with total length, diagnose pansteatitis to a predictive accuracy of 92 percent. In addition, several morphometric traits (total length, age, weight) were also associated with pansteatitis. On-going research will focus on further evaluating the use of blood chemistry to classify pansteatitis across different species, trophic levels, and within different sites along the Olifants River. PMID:27115488

  19. Predictive Blood Chemistry Parameters for Pansteatitis-Affected Mozambique Tilapia (Oreochromis mossambicus).

    PubMed

    Bowden, John A; Cantu, Theresa M; Chapman, Robert W; Somerville, Stephen E; Guillette, Matthew P; Botha, Hannes; Hoffman, Andre; Luus-Powell, Wilmien J; Smit, Willem J; Lebepe, Jeffrey; Myburgh, Jan; Govender, Danny; Tucker, Jonathan; Boggs, Ashley S P; Guillette, Louis J

    2016-01-01

    One of the largest river systems in South Africa, the Olifants River, has experienced significant changes in water quality due to anthropogenic activities. Since 2005, there have been various "outbreaks" of the inflammatory disease pansteatitis in several vertebrate species. Large-scale pansteatitis-related mortality events have decimated the crocodile population at Lake Loskop and decreased the population at Kruger National Park. Most pansteatitis-related diagnoses within the region are conducted post-mortem by either gross pathology or histology. The application of a non-lethal approach to assess the prevalence and pervasiveness of pansteatitis in the Olifants River region would be of great importance for the development of a management plan for this disease. In this study, several plasma-based biomarkers accurately classified pansteatitis in Mozambique tilapia (Oreochromis mossambicus) collected from Lake Loskop using a commercially available benchtop blood chemistry analyzer combined with data interpretation via artificial neural network analysis. According to the model, four blood chemistry parameters (calcium, sodium, total protein and albumin), in combination with total length, diagnose pansteatitis to a predictive accuracy of 92 percent. In addition, several morphometric traits (total length, age, weight) were also associated with pansteatitis. On-going research will focus on further evaluating the use of blood chemistry to classify pansteatitis across different species, trophic levels, and within different sites along the Olifants River.

  20. Kinetics of oxidative degradation of white wines and how they are affected by selected technological parameters.

    PubMed

    Ferreira, Antonio César Silva; de Pinho, Paula Guedes; Rodrigues, Paula; Hogg, Timothy

    2002-10-01

    The negative effects of oxygen on white wine quality and the various factors which influence it (including temperature, dissolved oxygen, pH, and free SO(2)) are well documented both at the sensory and compositional levels. What is less defined is the quantitative relationship between these parameters and the kinetics of the development of the negative effects of oxidation. The experiment presented here attempts to generate data which can be used to predictively model the oxidative degradation of white wines. Bottled wines were submitted to extreme conditions (45 degrees C temperature, O(2) saturation) during 3 months witth samples taken every 15 days for both sensorial and chemical analysis (GC-O/FPD/MS, 420 nm). The synergistic effects of increasing temperature and O(2) at lower pH are evident, both on the decrease in levels of terpene alcohols and norisoprenoids (which impart floral aromas), and on the development of off-flavors such as "honey-like", "boiled-potato", and "farm-feed" associated with the presence of phenylacetaldehyde, methional, and 1,1,6-trimethyl-1,2-dihydronaphthalene. PMID:12358460

  1. Dexamethasone acutely regulates endocrine parameters in stallions and subsequently affects gene expression in testicular germ cells.

    PubMed

    Ing, N H; Brinsko, S P; Curley, K O; Forrest, D W; Love, C C; Hinrichs, K; Vogelsang, M M; Varner, D D; Welsh, T H

    2015-01-01

    Testicular steroidogenesis and spermatogenesis are negatively impacted by stress-related hormones such as glucocorticoids. The effects of two injections of a therapeutic dose of dexamethasone (a synthetic glucocorticoid, 0.1mg/kg; i.v.) given 24h apart to each of three stallions were investigated and compared to three saline-injected control stallions. Dexamethasone decreased circulating concentrations of cortisol by 50% at 24h after the initial injection. Serum testosterone decreased by a maximum of 94% from 4 to 20h after the initial injection of dexamethasone. Semen parameters of the dexamethasone-treated stallions were unchanged in the subsequent two weeks. Two weeks after treatment, stallions were castrated. Functional genomic analyses of the testes revealed that, of eight gene products analyzed, dexamethasone depressed concentrations of heat shock protein DNAJC4 and sperm-specific calcium channel CATSPER1 mRNAs by more than 60%. Both genes are expressed in germ cells during spermiogenesis and have been related to male fertility in other species, including humans. This is the first report of decreased DNAJC4 and CATSPER1 mRNA concentrations in testes weeks after dexamethasone treatment. Concentrations of these mRNAs in sperm may be useful as novel markers of fertility in stallions. PMID:25487569

  2. Parameters affecting the accuracy of oxide thickness prediction in thin metal-oxide-semiconductor structures

    NASA Astrophysics Data System (ADS)

    Mohaidat, J. M.; Ahmad-Bitar, Riyad N.

    2004-01-01

    On the basis of the solution of the time dependent Schrödinger equation within the framework of the effective mass theory, a complete quantum mechanical electron tunneling through a biased square potential model with abrupt interfaces was deduced. Barriers of 3 eV height and widths up to 140 Å were investigated. Current density-voltage ( J- V) curves were computed for Al/SiO 2/ n+Si structure. The computed J- V curves exhibited oscillations at applied voltages above (Fowler-Nordheim tunneling) and below (direct tunneling) 3 V. For oxide thickness estimation, the position of the oscillation extrema from this quantum mechanical model were fitted to a wave interference formula and showed excellent agreement for oxide layer widths less than 50 Å. However, a systematic deviation appeared for layers larger than 50 Å. We show that the electron energy distribution at the injection layer and the electron effective mass on layers other than the oxide layer are important parameters for accurate oxide thickness estimation.

  3. Do fattening process and biological parameters affect the accumulation of metals in Atlantic bluefin tuna?

    PubMed

    Milatou, Niki; Dassenakis, Manos; Megalofonou, Persefoni

    2015-01-01

    The objective of this study was to determine the current levels of heavy metals and trace elements in Atlantic bluefin tuna muscle tissues and how they are influenced by the fattening process and various life history parameters to ascertain whether the concentrations in muscle tissue exceed the maximum levels defined by the European Commission Decision and to evaluate the health risk posed by fish consumption. A total of 20 bluefin tuna reared in sea cages, ranging from 160 to 295 cm in length and from 80 to 540 kg in weight, were sampled from a bluefin tuna farm in the Ionian Sea. The condition factor K of each specimen was calculated and their age was estimated. Heavy metal and trace element (Hg, Zn, Fe and Cu) contents were determined in muscle tissue using cold vapour atomic absorption spectrometry and flame and graphite furnace atomic absorption spectrometry. The total Hg concentrations ranged from 0.28 to 1.28 mg kg(-1) w/w, Zn from 5.81 to 76.37 mg kg(-1) w/w, Fe from 12.14 to 39.58 mg kg(-1) w/w, and Cu from 0.36 to 0.94 mg kg(-1) w/w. Only 5% of the muscle samples of tuna contained Hg above the maximum level laid down by the European Commission Decision. Moreover, 15% of the muscle samples contained Zn above the maximum level, while Fe and Cu concentrations were within the acceptable tolerable guideline values. The reared bluefin tuna had lower concentrations of Hg than the wild ones from the Mediterranean Sea. Hg and Fe concentrations showed a positive relationship with size and age of bluefin tuna, whereas negative relationships were found for the concentrations of Zn and Cu. The estimated dietary intake values of the analysed metals were mostly below the derived guidelines.

  4. Developmental methoxychlor exposure affects multiple reproductive parameters and ovarian folliculogenesis and gene expression in adult rats.

    PubMed

    Armenti, AnnMarie E; Zama, Aparna Mahakali; Passantino, Lisa; Uzumcu, Mehmet

    2008-12-01

    Methoxychlor (MXC) is an organochlorine pesticide with estrogenic, anti-estrogenic, and anti-androgenic properties. To investigate whether transient developmental exposure to MXC could cause adult ovarian dysfunction, we exposed Fischer rats to 20 microg/kg/day (low dose; environmentally relevant dose) or 100 mg/kg/day (high dose) MXC between 19 days post coitum and postnatal day 7. Multiple reproductive parameters, serum hormone levels, and ovarian morphology and molecular markers were examined from prepubertal through adult stages. High dose MXC accelerated pubertal onset and first estrus, reduced litter size, and increased irregular cyclicity (P<0.05). MXC reduced superovulatory response to exogenous gonadotropins in prepubertal females (P<0.05). Rats exposed to high dose MXC had increasing irregular estrous cyclicity beginning at 4 months of age, with all animals showing abnormal cycles by 6 months. High dose MXC reduced serum progesterone, but increased luteinizing hormone (LH). Follicular composition analysis revealed an increase in the percentage of preantral and early antral follicles and a reduction in the percentage of corpora lutea in high dose MXC-treated ovaries (P<0.05). Immunohistochemical staining and quantification of the staining intensity showed that estrogen receptor beta was reduced by high dose MXC while anti-Mullerian hormone was upregulated by both low- and high dose MXC in preantral and early antral follicles (P<0.05). High dose MXC significantly reduced LH receptor expression in large antral follicles (P<0.01), and down-regulated cytochrome P450 side-chain cleavage. These results demonstrated that developmental MXC exposure results in reduced ovulation and fertility and premature aging, possibly by altering ovarian gene expression and folliculogenesis.

  5. Developmental methoxychlor exposure affects multiple reproductive parameters and ovarian folliculogenesis and gene expression in adult rats

    SciTech Connect

    Armenti, AnnMarie E.; Zama, Aparna Mahakali; Passantino, Lisa; Uzumcu, Mehmet

    2008-12-01

    Methoxychlor (MXC) is an organochlorine pesticide with estrogenic, anti-estrogenic, and anti-androgenic properties. To investigate whether transient developmental exposure to MXC could cause adult ovarian dysfunction, we exposed Fischer rats to 20 {mu}g/kg/day (low dose; environmentally relevant dose) or 100 mg/kg/day (high dose) MXC between 19 days post coitum and postnatal day 7. Multiple reproductive parameters, serum hormone levels, and ovarian morphology and molecular markers were examined from prepubertal through adult stages. High dose MXC accelerated pubertal onset and first estrus, reduced litter size, and increased irregular cyclicity (P < 0.05). MXC reduced superovulatory response to exogenous gonadotropins in prepubertal females (P < 0.05). Rats exposed to high dose MXC had increasing irregular estrous cyclicity beginning at 4 months of age, with all animals showing abnormal cycles by 6 months. High dose MXC reduced serum progesterone, but increased luteinizing hormone (LH). Follicular composition analysis revealed an increase in the percentage of preantral and early antral follicles and a reduction in the percentage of corpora lutea in high dose MXC-treated ovaries (P < 0.05). Immunohistochemical staining and quantification of the staining intensity showed that estrogen receptor {beta} was reduced by high dose MXC while anti-Mullerian hormone was upregulated by both low- and high dose MXC in preantral and early antral follicles (P < 0.05). High dose MXC significantly reduced LH receptor expression in large antral follicles (P < 0.01), and down-regulated cytochrome P450 side-chain cleavage. These results demonstrated that developmental MXC exposure results in reduced ovulation and fertility and premature aging, possibly by altering ovarian gene expression and folliculogenesis.

  6. How Different Genetically Manipulated Brassica Genotypes Affect Life Table Parameters of Plutella xylostella (Lepidoptera: Plutellidae).

    PubMed

    Nikooei, Mehrnoosh; Fathipour, Yaghoub; Jalali Javaran, Mokhtar; Soufbaf, Mahmoud

    2015-04-01

    The fitness of Plutella xylostella L. on different genetically manipulated Brassica plants, including canola's progenitor (Brassica rapa L.), two cultivated canola cultivars (Opera and RGS003), one hybrid (Hyula401), one gamma-ray mutant-RGS003, and one transgenic (PF) genotype was compared using two-sex and female-based life table parameters. All experiments were conducted in a growth chamber at 25±1°C, 65±5% relative humidity, and a photoperiod of 16:8 (L:D) h. There were significant differences in duration of different life stages of P. xylostella on different plant genotypes. The shortest (13.92 d) and longest (24.61 d) total developmental time were on Opera and PF, respectively. The intrinsic rate of increase of P. xylostella ranged between 0.236 (Opera) and 0.071 day(-1) (PF). The highest (60.79 offspring) and lowest (7.88 offspring) net reproductive rates were observed on Opera and PF, respectively. Comparison of intrinsic rate of increase, net reproductive rates, finite rate of increase, mean generation time, fecundity, and survivorship of P. xylostella on the plant genotypes suggested that this pest performed well on cultivars (RGS003 and Opera) and performed poorly on the other manipulated genotypes especially on mutant-RGS003 and PF. Glucosinolate levels were significantly higher in damaged plants than undamaged ones and the lowest and highest concentrations of glucosinolates were found in transgenic genotype and canola's progenitor, respectively. Interestingly, our results showed that performance and fitness of this pest was better on canola's progenitor and cultivated plants, which had high levels of glucosinolate.

  7. How Different Genetically Manipulated Brassica Genotypes Affect Life Table Parameters of Plutella xylostella (Lepidoptera: Plutellidae).

    PubMed

    Nikooei, Mehrnoosh; Fathipour, Yaghoub; Jalali Javaran, Mokhtar; Soufbaf, Mahmoud

    2015-04-01

    The fitness of Plutella xylostella L. on different genetically manipulated Brassica plants, including canola's progenitor (Brassica rapa L.), two cultivated canola cultivars (Opera and RGS003), one hybrid (Hyula401), one gamma-ray mutant-RGS003, and one transgenic (PF) genotype was compared using two-sex and female-based life table parameters. All experiments were conducted in a growth chamber at 25±1°C, 65±5% relative humidity, and a photoperiod of 16:8 (L:D) h. There were significant differences in duration of different life stages of P. xylostella on different plant genotypes. The shortest (13.92 d) and longest (24.61 d) total developmental time were on Opera and PF, respectively. The intrinsic rate of increase of P. xylostella ranged between 0.236 (Opera) and 0.071 day(-1) (PF). The highest (60.79 offspring) and lowest (7.88 offspring) net reproductive rates were observed on Opera and PF, respectively. Comparison of intrinsic rate of increase, net reproductive rates, finite rate of increase, mean generation time, fecundity, and survivorship of P. xylostella on the plant genotypes suggested that this pest performed well on cultivars (RGS003 and Opera) and performed poorly on the other manipulated genotypes especially on mutant-RGS003 and PF. Glucosinolate levels were significantly higher in damaged plants than undamaged ones and the lowest and highest concentrations of glucosinolates were found in transgenic genotype and canola's progenitor, respectively. Interestingly, our results showed that performance and fitness of this pest was better on canola's progenitor and cultivated plants, which had high levels of glucosinolate. PMID:26470162

  8. Theoretical, numerical and experimental study of geometrical parameters that affect anisotropy measurements in polarization-resolved SHG microscopy.

    PubMed

    Teulon, Claire; Gusachenko, Ivan; Latour, Gaël; Schanne-Klein, Marie-Claire

    2015-04-01

    Polarization-resolved second harmonic generation (P-SHG) microscopy is an efficient imaging modality for in situ observation of biopolymers structure in tissues, providing information about their mean in-plane orientation and their molecular structure and 3D distribution. Nevertheless, P-SHG signal build-up in a strongly focused regime is not throroughly understood yet, preventing reliable and reproducible measurements. In this study, theoretical analysis, vectorial numerical simulations and experiments are performed to understand how geometrical parameters, such as excitation and collection numerical apertures and detection direction, affect P-SHG imaging in homogeneous collagen tissues. A good agreement is obtained in tendon and cornea, showing that detection geometry significantly affects the SHG anisotropy measurements, but not the measurements of collagen in-plane orientation. PMID:25968762

  9. Space colonization.

    PubMed

    2002-12-01

    NASA interest in colonization encompasses space tourism; space exploration; space bases in orbit, at L1, on the Moon, or on Mars; in-situ resource utilization; and planetary terraforming. Activities progressed during 2002 in areas such as Mars colonies, hoppers, and biomass; space elevators and construction; and in-situ consumables.

  10. Space colonization.

    PubMed

    2002-12-01

    NASA interest in colonization encompasses space tourism; space exploration; space bases in orbit, at L1, on the Moon, or on Mars; in-situ resource utilization; and planetary terraforming. Activities progressed during 2002 in areas such as Mars colonies, hoppers, and biomass; space elevators and construction; and in-situ consumables. PMID:12506926

  11. Altered membrane lipid composition and functional parameters of circulating cells in cockles (Cerastoderma edule) affected by disseminated neoplasia.

    PubMed

    Le Grand, Fabienne; Soudant, Philippe; Marty, Yanic; Le Goïc, Nelly; Kraffe, Edouard

    2013-01-01

    Membrane lipid composition and morpho-functional parameters were investigated in circulating cells of the edible cockle (Cerastoderma edule) affected by disseminated neoplasia (neoplastic cells) and compared to those from healthy cockles (hemocytes). Membrane sterol levels, phospholipid (PL) class and subclass proportions and their respective fatty acid (FA) compositions were determined. Morpho-functional parameters were evaluated through total hemocyte count (THC), mortality rate, phagocytosis ability and reactive oxygen species (ROS) production. Both morpho-functional parameters and lipid composition were profoundly affected in neoplastic cells. These dedifferentiated cells displayed higher THC (5×), mortality rate (3×) and ROS production with addition of carbonyl cyanide m-chloro phenylhydrazone (1.7×) but lower phagocytosis ability (½×), than unaffected hemocytes. Total PL amounts were higher in neoplastic cells than in hemocytes (12.3 and 5.1 nmol×10(-6) cells, respectively). However, sterols and a particular subclass of PL (plasmalogens; 1-alkenyl-2-acyl PL) were present in similar amounts in both cell type membranes. This led to a two times lower proportion of these membrane lipid constituents in neoplastic cells when compared to hemocytes (20.5% vs. 42.1% of sterols in total membrane lipids and 21.7% vs. 44.2% of plasmalogens among total PL, respectively). Proportions of non-methylene interrupted FA- and 20:1n-11-plasmalogen molecular species were the most impacted in neoplastic cells when compared to hemocytes (⅓× and ¼×, respectively). These changes in response to this leukemia-like disease in bivalves highlight the specific imbalance of plasmalogens and sterols in neoplastic cells, in comparison to the greater stability of other membrane lipid components.

  12. Altered membrane lipid composition and functional parameters of circulating cells in cockles (Cerastoderma edule) affected by disseminated neoplasia.

    PubMed

    Le Grand, Fabienne; Soudant, Philippe; Marty, Yanic; Le Goïc, Nelly; Kraffe, Edouard

    2013-01-01

    Membrane lipid composition and morpho-functional parameters were investigated in circulating cells of the edible cockle (Cerastoderma edule) affected by disseminated neoplasia (neoplastic cells) and compared to those from healthy cockles (hemocytes). Membrane sterol levels, phospholipid (PL) class and subclass proportions and their respective fatty acid (FA) compositions were determined. Morpho-functional parameters were evaluated through total hemocyte count (THC), mortality rate, phagocytosis ability and reactive oxygen species (ROS) production. Both morpho-functional parameters and lipid composition were profoundly affected in neoplastic cells. These dedifferentiated cells displayed higher THC (5×), mortality rate (3×) and ROS production with addition of carbonyl cyanide m-chloro phenylhydrazone (1.7×) but lower phagocytosis ability (½×), than unaffected hemocytes. Total PL amounts were higher in neoplastic cells than in hemocytes (12.3 and 5.1 nmol×10(-6) cells, respectively). However, sterols and a particular subclass of PL (plasmalogens; 1-alkenyl-2-acyl PL) were present in similar amounts in both cell type membranes. This led to a two times lower proportion of these membrane lipid constituents in neoplastic cells when compared to hemocytes (20.5% vs. 42.1% of sterols in total membrane lipids and 21.7% vs. 44.2% of plasmalogens among total PL, respectively). Proportions of non-methylene interrupted FA- and 20:1n-11-plasmalogen molecular species were the most impacted in neoplastic cells when compared to hemocytes (⅓× and ¼×, respectively). These changes in response to this leukemia-like disease in bivalves highlight the specific imbalance of plasmalogens and sterols in neoplastic cells, in comparison to the greater stability of other membrane lipid components. PMID:23333874

  13. Optimization of parameters affecting signal intensity in an LTQ-orbitrap in negative ion mode: A design of experiments approach.

    PubMed

    Lemonakis, Nikolaos; Skaltsounis, Alexios-Leandros; Tsarbopoulos, Anthony; Gikas, Evagelos

    2016-01-15

    A multistage optimization of all the parameters affecting detection/response in an LTQ-orbitrap analyzer was performed, using a design of experiments methodology. The signal intensity, a critical issue for mass analysis, was investigated and the optimization process was completed in three successive steps, taking into account the three main regions of an orbitrap, the ion generation, the ion transmission and the ion detection regions. Oleuropein and hydroxytyrosol were selected as the model compounds. Overall, applying this methodology the sensitivity was increased more than 24%, the resolution more than 6.5%, whereas the elapsed scan time was reduced nearly to its half. A high-resolution LTQ Orbitrap Discovery mass spectrometer was used for the determination of the analytes of interest. Thus, oleuropein and hydroxytyrosol were infused via the instruments syringe pump and they were analyzed employing electrospray ionization (ESI) in the negative high-resolution full-scan ion mode. The parameters of the three main regions of the LTQ-orbitrap were independently optimized in terms of maximum sensitivity. In this context, factorial design, response surface model and Plackett-Burman experiments were performed and analysis of variance was carried out to evaluate the validity of the statistical model and to determine the most significant parameters for signal intensity. The optimum MS conditions for each analyte were summarized and the method optimum condition was achieved by maximizing the desirability function. Our observation showed good agreement between the predicted optimum response and the responses collected at the predicted optimum conditions.

  14. Development of an auditory emotion recognition function using psychoacoustic parameters based on the International Affective Digitized Sounds.

    PubMed

    Choi, Youngimm; Lee, Sungjun; Jung, SungSoo; Choi, In-Mook; Park, Yon-Kyu; Kim, Chobok

    2015-12-01

    The purpose of this study was to develop an auditory emotion recognition function that could determine the emotion caused by sounds coming from the environment in our daily life. For this purpose, sound stimuli from the International Affective Digitized Sounds (IADS-2), a standardized database of sounds intended to evoke emotion, were selected, and four psychoacoustic parameters (i.e., loudness, sharpness, roughness, and fluctuation strength) were extracted from the sounds. Also, by using an emotion adjective scale, 140 college students were tested to measure three basic emotions (happiness, sadness, and negativity). From this discriminant analysis to predict basic emotions from the psychoacoustic parameters of sound, a discriminant function with overall discriminant accuracy of 88.9% was produced from training data. In order to validate the discriminant function, the same four psychoacoustic parameters were extracted from 46 sound stimuli collected from another database and substituted into the discriminant function. The results showed that an overall discriminant accuracy of 63.04% was confirmed. Our findings provide the possibility that daily-life sounds, beyond voice and music, can be used in a human-machine interface.

  15. A mathematical model to predict the size of the pellets formed in freeze pelletization techniques: parameters affecting pellet size.

    PubMed

    Cheboyina, Sreekhar; O'Haver, John; Wyandt, Christy M

    2006-01-01

    A mathematical model was developed based on the theory of drop formation to predict the size of the pellets formed in the freeze pelletization process. Further the model was validated by studying the effect of various parameters on the pellet size such as viscosity of the pellet forming and column liquids, surface/interfacial tension, density difference between pellet forming and column liquids; size, shape, and material of construction of the needle tips and temperatures maintained in the columns. In this study, pellets were prepared from different matrices including polyethylene glycols and waxes. The column liquids studied were silicone oils and aqueous glycerol solutions. The surface/interfacial tension, density difference between pellet forming and column liquids and needle tip size were found to be the most important factors affecting pellet size. The viscosity of the column liquid was not found to significantly affect the size of the pellets. The size of the pellets was also not affected by the pellet forming liquids of low viscosities. An increase in the initial column temperature slightly decreased the pellet size. The mathematical model developed was found to successfully predict the size of the pellets with an average error of 3.32% for different matrices that were studied.

  16. Genetic selection to increase bone strength affects prevalence of keel bone damage and egg parameters in commercially housed laying hens.

    PubMed

    Stratmann, A; Fröhlich, E K F; Gebhardt-Henrich, S G; Harlander-Matauschek, A; Würbel, H; Toscano, M J

    2016-05-01

    The prevalence of keel bone damage as well as external egg parameters of 2 pure lines divergently selected for high (H) and low (L) bone strength were investigated in 2 aviary systems under commercial conditions. A standard LSL hybrid was used as a reference group. Birds were kept mixed per genetic line (77 hens of the H and L line and 201 or 206 hens of the LSL line, respectively, per pen) in 8 pens of 2 aviary systems differing in design. Keel bone status and body mass of 20 focal hens per line and pen were assessed at 17, 18, 23, 30, 36, 43, 52, and 63 wk of age. External egg parameters (i.e., egg mass, eggshell breaking strength, thickness, and mass) were measured using 10 eggs per line at both 38 and 57 wk of age. Body parameters (i.e. tarsus and third primary wing feather length to calculate index of wing loading) were recorded at 38 wk of age and mortality per genetic line throughout the laying cycle. Bone mineral density (BMD) of 15 keel bones per genetic line was measured after slaughter to confirm assignment of the experimental lines. We found a greater BMD in the H compared with the L and LSL lines. Fewer keel bone fractures and deviations, a poorer external egg quality, as well as a lower index of wing loading were found in the H compared with the L line. Mortality was lower and production parameters (e.g., laying performance) were higher in the LSL line compared with the 2 experimental lines. Aviary design affected prevalence of keel bone damage, body mass, and mortality. We conclude that selection of specific bone traits associated with bone strength as well as the related differences in body morphology (i.e., lower index of wing loading) have potential to reduce keel bone damage in commercial settings. Also, the housing environment (i.e., aviary design) may have additive effects. PMID:26944960

  17. Genetic selection to increase bone strength affects prevalence of keel bone damage and egg parameters in commercially housed laying hens.

    PubMed

    Stratmann, A; Fröhlich, E K F; Gebhardt-Henrich, S G; Harlander-Matauschek, A; Würbel, H; Toscano, M J

    2016-05-01

    The prevalence of keel bone damage as well as external egg parameters of 2 pure lines divergently selected for high (H) and low (L) bone strength were investigated in 2 aviary systems under commercial conditions. A standard LSL hybrid was used as a reference group. Birds were kept mixed per genetic line (77 hens of the H and L line and 201 or 206 hens of the LSL line, respectively, per pen) in 8 pens of 2 aviary systems differing in design. Keel bone status and body mass of 20 focal hens per line and pen were assessed at 17, 18, 23, 30, 36, 43, 52, and 63 wk of age. External egg parameters (i.e., egg mass, eggshell breaking strength, thickness, and mass) were measured using 10 eggs per line at both 38 and 57 wk of age. Body parameters (i.e. tarsus and third primary wing feather length to calculate index of wing loading) were recorded at 38 wk of age and mortality per genetic line throughout the laying cycle. Bone mineral density (BMD) of 15 keel bones per genetic line was measured after slaughter to confirm assignment of the experimental lines. We found a greater BMD in the H compared with the L and LSL lines. Fewer keel bone fractures and deviations, a poorer external egg quality, as well as a lower index of wing loading were found in the H compared with the L line. Mortality was lower and production parameters (e.g., laying performance) were higher in the LSL line compared with the 2 experimental lines. Aviary design affected prevalence of keel bone damage, body mass, and mortality. We conclude that selection of specific bone traits associated with bone strength as well as the related differences in body morphology (i.e., lower index of wing loading) have potential to reduce keel bone damage in commercial settings. Also, the housing environment (i.e., aviary design) may have additive effects.

  18. Acute colonic ischaemia in rats results in long-term structural changes without alterations of colonic sensitivity

    PubMed Central

    Ravnefjord, Anna; Pettersson, Madeleine; Rehnström, Erika; Martinez, Vicente

    2008-01-01

    Colonic ischaemia and mast cells have been involved in the pathophysiology of the functional gastrointestinal disorder irritable bowel syndrome, although the cause–effect relationships remain unknown. We assessed long-term histopathological and functional changes associated to an acute ischaemic episode (1 h) of the colon, followed by 8-week recovery, in rats. Functional colonic alterations [sensitivity during colorectal distension (CRD), compliance and propulsive motility] were assessed regularly during the recovery. Colonic histopathology (presence of inflammation, morphometric alterations and variations in neuronal density in the enteric nervous system) 8-week postischaemia was assessed. Following ischaemia, none of the functional parameters tested (motility, sensitivity and compliance) were affected. At necropsy, the colon presented an overall normal appearance with an increase in weight of the ischaemic area (mg/cm: 99 ± 6; P < 0.05 vs. control: 81 ± 4 or sham ischaemia: 81 ± 3). Histopathological evaluations revealed the presence of a local infiltrate of mast cells in the area of ischaemia (nb of mast cells: 142 ± 50; P < 0.05 vs. control, 31 ± 14 or sham ischaemia: 40 ± 16), without other significant alterations. Animals subjected to colonic ischaemia and treated 8 weeks later with the mast cell degranulator, compound 48/80, showed no changes in CRD-related pain responses. These studies show that acute colonic ischaemia is associated with the presence of a long-term local infiltration of mast cells, located within the serosa and muscle layers, despite the absence of functional changes, including colonic sensitivity. Considering the important pathophysiological functions of mast cells, the observed mast cell infiltration may be involved in ischaemia-induced functional changes yet to be characterized. PMID:19134057

  19. Practice parameters for early colon cancer management: Italian Society of Colorectal Surgery (Società Italiana di Chirurgia Colo-Rettale; SICCR) guidelines.

    PubMed

    Bianco, F; Arezzo, A; Agresta, F; Coco, C; Faletti, R; Krivocapic, Z; Rotondano, G; Santoro, G A; Vettoretto, N; De Franciscis, S; Belli, A; Romano, G M

    2015-10-01

    Early colon cancer (ECC) has been defined as a carcinoma with invasion limited to the submucosa regardless of lymph node status and according to the Royal College of Pathologists as TNM stage T1 NX M0. As the potential risk of lymph node metastasis ranges from 6 to 17% and the preoperative assessment of lymph node metastasis is not reliable, the management of ECC is still controversial, varying from endoscopic to radical resection. A meeting on recent advances on the management of colorectal polyps endorsed by the Italian Society of Colorectal Surgery (SICCR) took place in April 2014, in Genoa (Italy). Based on this material the SICCR decided to issue guidelines updating the evidence and to write a position statement paper in order to define the diagnostic and therapeutic strategy for ECC treatment in context of the Italian healthcare system.

  20. Optimization of the parameters affecting the shape and position of crystal-melt interface in YAG single crystal growth

    NASA Astrophysics Data System (ADS)

    Asadian, Morteza; Seyedein, S. H.; Aboutalebi, M. R.; Maroosi, A.

    2009-01-01

    In Czochralski method, the shape of crystal-melt interface and its position play a major role on the quality of single crystals. In the Czochralski crystal growth process having a nearly flat interface, a single crystal with less structural defect, uniform physical properties and homogenous chemical composition is obtained. In the present study, firstly a 2-D fluid flow and solidification model was developed to simulate the YAG single crystal growth process using a finite volume method. The fluid flow and solidification heat transfer model was further tested by available experimental data. The verified fluid flow and solidification heat transfer model was used to build an artificial neural network and trained to optimize the parameters affecting the shape and position of the interface. Finally, the trained neural network was employed to optimize the operating parameters such as pulling rate, rotation speed of the crystal, ambient gas and temperature of crucible wall to obtain a closely flat crystal-melt interface. The optimized variables were eventually used in fluid flow model to evaluate the performance of the optimization model.

  1. Dynamic Testing of a Pre-stretched Flexible Tube for Identifying the Factors Affecting Modal Parameter Estimation

    NASA Astrophysics Data System (ADS)

    Unnikrishnan, Madhusudanan; Rajan, Akash; Basanthvihar Raghunathan, Binulal; Kochupillai, Jayaraj

    2016-06-01

    Experimental modal analysis is the primary tool for obtaining the fundamental dynamic characteristics like natural frequency, mode shape and modal damping ratio that determine the behaviour of any structure under dynamic loading conditions. This paper discusses about a carefully designed experimental method for calculating the dynamic characteristics of a pre-stretched horizontal flexible tube made of polyurethane material. The factors that affect the modal parameter estimation like the application time of shaker excitation, pause time between successive excitation cycles, averaging and windowing of measured signal, as well as the precautions to be taken during the experiment are explained in detail. The modal parameter estimation is done using MEscopeVESTM software. A finite element based pre-stressed modal analysis of the flexible tube is also done using ANSYS ver.14.0 software. The experimental and analytical results agreed well. The proposed experimental methodology may be extended for carrying out the modal analysis of many flexible structures like inflatables, tires and membranes.

  2. How do alternative root water uptake models affect the inverse estimation of soil hydraulic parameters and the prediction of evapotranspiration?

    NASA Astrophysics Data System (ADS)

    Gayler, Sebastian; Salima-Sultana, Daisy; Selle, Benny; Ingwersen, Joachim; Wizemann, Hans-Dieter; Högy, Petra; Streck, Thilo

    2016-04-01

    Soil water extraction by roots affects the dynamics and distribution of soil moisture and controls transpiration, which influences soil-vegetation-atmosphere feedback processes. Consequently, root water uptake requires close attention when predicting water fluxes across the land surface, e.g., in agricultural crop models or in land surface schemes of weather and climate models. The key parameters for a successful simultaneous simulation of soil moisture dynamics and evapotranspiration in Richards equation-based models are the soil hydraulic parameters, which describe the shapes of the soil water retention curve and the soil hydraulic conductivity curve. As measurements of these parameters are expensive and their estimation from basic soil data via pedotransfer functions is rather inaccurate, the values of the soil hydraulic parameters are frequently inversely estimated by fitting the model to measured time series of soil water content and evapotranspiration. It is common to simulate root water uptake and transpiration by simple stress functions, which describe from which soil layer water is absorbed by roots and predict when total crop transpiration is decreased in case of soil water limitations. As for most of the biogeophysical processes simulated in crop and land surface models, there exist several alternative functional relationships for simulating root water uptake and there is no clear reason for preferring one process representation over another. The error associated with alternative representations of root water uptake, however, contributes to structural model uncertainty and the choice of the root water uptake model may have a significant impact on the values of the soil hydraulic parameters estimated inversely. In this study, we use the agroecosystem model system Expert-N to simulate soil moisture dynamics and evapotranspiration at three agricultural field sites located in two contrasting regions in Southwest Germany (Kraichgau, Swabian Alb). The Richards

  3. Improvement of Oxidative and Metabolic Parameters by Cellfood Administration in Patients Affected by Neurodegenerative Diseases on Chelation Treatment

    PubMed Central

    Fulgenzi, Alessandro; Giuseppe, Rachele De; Bamonti, Fabrizia; Ferrero, Maria Elena

    2014-01-01

    Objective. This prospective pilot study aimed at evaluating the effects of therapy with antioxidant compounds (Cellfood, and other antioxidants) on patients affected by neurodegenerative diseases (ND), who displayed toxic metal burden and were subjected to chelation treatment with the chelating agent calcium disodium ethylenediaminetetraacetic acid (CaNa2EDTA or EDTA). Methods. Two groups of subjects were studied: (a) 39 patients affected by ND and (b) 11 subjects unaffected by ND (controls). The following blood parameters were analyzed before and after three months' treatment with chelation + Cellfood or chelation + other antioxidants: oxidative status (reactive oxygen species, ROS; total antioxidant capacity, TAC; oxidized LDL, oxLDL; glutathione), homocysteine, vitamin B12, and folate. Results. After 3-months' chelation + Cellfood administration oxLDL decreased, ROS levels were significantly lower, and TAC and glutathione levels were significantly higher than after chelation + other antioxidants treatment, both in ND patients and in controls. Moreover, homocysteine metabolism had also improved in both groups. Conclusions. Chelation + Cellfood treatment was more efficient than chelation + other antioxidants improving oxidative status and homocysteine metabolism significantly in ND patients and controls. Although limited to a small number of cases, this study showed how helpful antioxidant treatment with Cellfood was in improving the subjects' metabolic conditions. PMID:25114898

  4. TH-C-18A-09: Exam and Patient Parameters Affecting the DNA Damage Response Following CT Studies

    SciTech Connect

    Elgart, S; Adibi, A; Bostani, M; Ruehm, S; Enzmann, D; McNitt-Gray, M; Iwamoto, K

    2014-06-15

    Purpose: To identify exam and patient parameters affecting the biological response to CT studies using in vivo and ex vivo blood samples. Methods: Blood samples were collected under IRB approval from 16 patients undergoing clinically-indicated CT exams. Blood was procured prior to, immediately after and 30minutes following irradiation. A sample of preexam blood was placed on the patient within the exam region for ex vivo analysis. Whole blood samples were fixed immediately following collection and stained for γH2AX to assess DNA damage response (DDR). Median fluorescence of treated samples was compared to non-irradiated control samples for each patient. Patients were characterized by observed biological kinetic response: (a) fast — phosphorylation increased by 2minutes and fell by 30minutes, (b) slow — phosphorylation continued to increase to 30minutes and (c) none — little change was observed or irradiated samples fell below controls. Total dose values were normalized to exam time for an averaged dose-rate in dose/sec for each exam. Relationships between patient biological responses and patient and exam parameters were investigated. Results: A clearer dose response at 30minutes is observed for young patients (<61yoa; R2>0.5) compared to old patients (>61yoa; R{sup 2}<0.11). Fast responding patients were significantly younger than slow responding patients (p<0.05). Unlike in vivo samples, age did not significantly affect the patient response ex vivo. Additionally, fast responding patients received exams with significantly smaller dose-rate than slow responding patients (p<0.05). Conclusion: Age is a significant factor in the biological response suggesting that DDR may be more rapid in a younger population and slower as the population ages. Lack of an agerelated response ex vivo suggests a systemic response to radiation not present when irradiated outside the body. Dose-rate affects the biological response suggesting that patient response may be related to

  5. PillCam colon capsule endoscopy (PCCE) in colonic diseases

    PubMed Central

    Carter, Dan

    2016-01-01

    Diseases affecting the colon are common worldwide and can cause a major health problem. Colorectal cancer (CRC) as well as Inflammatory bowel diseases represent a major cause of morbidity and mortality in western countries. PillCam colon capsule endoscopy (PCCE) is a novel and promising technology that can be useful for the screening and monitoring of colonic diseases. In the recent years many articles examined the use of various versions of PCCE—the 1st and 2nd generation versus various other endoscopic or radiologic modalities both for detection of colonic polyps or cancer and in both ulcerative colitis (UC) and Crohn’s disease. The aim of the current review is to provide up to date information regarding the use and usefulness of this method in these disease.

  6. PillCam colon capsule endoscopy (PCCE) in colonic diseases.

    PubMed

    Carter, Dan; Eliakim, Rami

    2016-08-01

    Diseases affecting the colon are common worldwide and can cause a major health problem. Colorectal cancer (CRC) as well as Inflammatory bowel diseases represent a major cause of morbidity and mortality in western countries. PillCam colon capsule endoscopy (PCCE) is a novel and promising technology that can be useful for the screening and monitoring of colonic diseases. In the recent years many articles examined the use of various versions of PCCE-the 1st and 2nd generation versus various other endoscopic or radiologic modalities both for detection of colonic polyps or cancer and in both ulcerative colitis (UC) and Crohn's disease. The aim of the current review is to provide up to date information regarding the use and usefulness of this method in these disease. PMID:27668227

  7. PillCam colon capsule endoscopy (PCCE) in colonic diseases

    PubMed Central

    Carter, Dan

    2016-01-01

    Diseases affecting the colon are common worldwide and can cause a major health problem. Colorectal cancer (CRC) as well as Inflammatory bowel diseases represent a major cause of morbidity and mortality in western countries. PillCam colon capsule endoscopy (PCCE) is a novel and promising technology that can be useful for the screening and monitoring of colonic diseases. In the recent years many articles examined the use of various versions of PCCE—the 1st and 2nd generation versus various other endoscopic or radiologic modalities both for detection of colonic polyps or cancer and in both ulcerative colitis (UC) and Crohn’s disease. The aim of the current review is to provide up to date information regarding the use and usefulness of this method in these disease. PMID:27668227

  8. Colon cancer - resources

    MedlinePlus

    Resources - colon cancer ... The following organizations are good resources for information on colon cancer : American Cancer Society -- www.cancer.org/cancer/colonandrectumcancer/index Colon Cancer Alliance -- www.ccalliance.org National ...

  9. Growth media simulating ileal and colonic environments affect the intracellular proteome and carbon fluxes of enterohemorrhagic Escherichia coli O157:H7 strain EDL933.

    PubMed

    Polzin, Sabrina; Huber, Claudia; Eylert, Eva; Elsenhans, Ines; Eisenreich, Wolfgang; Schmidt, Herbert

    2013-06-01

    In this study, the intracellular proteome of Escherichia coli O157:H7 strain EDL933 was analyzed by two-dimensional gel electrophoresis and matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) spectrometry after growth in simulated ileal environment media (SIEM) and simulated colonic environment media (SCEM) under aerobic and microaerobic conditions. Differentially expressed intracellular proteins were identified and allocated to functional protein groups. Moreover, metabolic fluxes were analyzed by isotopologue profiling with [U-(13)C(6)]glucose as a tracer. The results of this study show that EDL933 responds with differential expression of a complex network of proteins and metabolic pathways, reflecting the high metabolic adaptability of the strain. Growth in SIEM and SCEM is obviously facilitated by the upregulation of nucleotide biosynthesis pathway proteins and could be impaired by exposition to 50 µM 6-mercaptopurine under aerobic conditions. Notably, various stress and virulence factors, including Shiga toxin, were expressed without having contact with a human host.

  10. Dissecting systemic RNA interference in the red flour beetle Tribolium castaneum: parameters affecting the efficiency of RNAi.

    PubMed

    Miller, Sherry C; Miyata, Keita; Brown, Susan J; Tomoyasu, Yoshinori

    2012-01-01

    The phenomenon of RNAi, in which the introduction of dsRNA into a cell triggers the destruction of the corresponding mRNA resulting in a gene silencing effect, is conserved across a wide array of plant and animal phyla. However, the mechanism by which the dsRNA enters a cell, allowing the RNAi effect to occur throughout a multicellular organism (systemic RNAi), has only been studied extensively in certain plants and the nematode Caenorhabditis elegans. In recent years, RNAi has become a popular reverse genetic technique for gene silencing in many organisms. Although many RNAi techniques in non-traditional model organisms rely on the systemic nature of RNAi, little has been done to analyze the parameters required to obtain a robust systemic RNAi response. The data provided here show that the concentration and length of dsRNA have profound effects on the efficacy of the RNAi response both in regard to initial efficiency and duration of the effect in Tribolium castaneum. In addition, our analyses using a series of short dsRNAs and chimeric dsRNA provide evidence that dsRNA cellular uptake (and not the RNAi response itself) is the major step affected by dsRNA size in Tribolium. We also demonstrate that competitive inhibition of dsRNA can occur when multiple dsRNAs are injected together, influencing the effectiveness of RNAi. These data provide specific information essential to the design and implementation of RNAi based studies, and may provide insight into the molecular basis of the systemic RNAi response in insects. PMID:23133513

  11. What are the stimulation parameters that affect the extent of twitch force potentiation in the adductor pollicis muscle?

    PubMed

    Mettler, Joni A; Griffin, Lisa

    2010-12-01

    Muscle force potentiation affects force output during electrical stimulation. Few studies have examined stimulation train parameters that influence potentiation such as pulse number, stimulation frequency, train duration, and force-time integral and peak force produced during the train. Pulse-matched trains (100 pulses) at 7.5, 15, 25, 30, 50, and 100 Hz, and trains of varying pulse number (50, 100, and 200 pulses) at 30 and 50 Hz were delivered to the ulnar nerve of 10 (5 male, 5 female; 23.4 ± 0.9 years), healthy individuals in random order. Single twitches of the adductor pollicis muscle were elicited before and after each train with a rest interval of at least 5 min between each train. No differences in potentiation occurred across the pulse-matched trains at frequencies of 15-50 Hz (38.9 ± 5.4-44.6 ± 5.5%). Twitch force potentiation following the highest (100 Hz) and lowest (7.5 Hz) frequency trains were not significantly different and were lower than the other 100 pulse-matched trains. As pulse number increased, potentiation increased for both the 30 and 50-Hz trains. There was a significant positive correlation between force potentiation and force-time integral produced by the stimulation train, r = 0.70. The results indicate that potentiation magnitude is dependent on the force-time integral produced during the test train and the number of pulses delivered, independent of stimulation frequency. PMID:20737164

  12. A comprehensive study of physical and physiological parameters that affect bio-sorption of metal pollutants from aqueous solutions

    NASA Astrophysics Data System (ADS)

    Fosso-Kankeu, E.; Mulaba-Bafubiandi, A. F.; Mamba, B. B.; Marjanovic, L.; Barnard, T. G.

    An attempt was made to remove silver (I), chromium (III), and lead (II) from aqueous solutions. To optimize the bio-sorption capacity of microorganisms ( Bacillus subtilis and Bacillaceae bacterium), the effect of process parameters such as pH, temperature, metal load and culture age on the metal uptake was investigated. Indigenous strains of B. subtilis and Bacillaceae bacterium found in gold and copper mines in South Africa were exposed to silver (I), chromium (III), and lead (II) solutions under different physico-chemical and physiological conditions. Optimum conditions for the uptake of silver (I), chromium (III) and lead (II) by microorganisms used in this study were determined. The pH range 7-8, higher temperature (45 °C) and stationary growth phase, were observed as being suitable physical and physiological conditions for optimum removal of metals (Ag-87.2%; Cr-94% and Pb-98.5%). On the other hand very low pH (3) adversely affected the metal removal ability of bacteria. Silver (I) was the most poorly uptaken metal. It was also found that silver inhibited bacteria growth. Attempt to elute metal from the above cell biomass showed that 56.6% silver (I) and 88.3% lead (II) could effectively be desorbed at pH 5. It was additionally observed that optimum conditions for metal removal were specific to microbial bio-sorbent and the targeted metal. Design and implementation of bioremediation processes therefore require thorough study of specific interactions among metals and bio-sorbents involved.

  13. Metabolism links bacterial biofilms and colon carcinogenesis.

    PubMed

    Johnson, Caroline H; Dejea, Christine M; Edler, David; Hoang, Linh T; Santidrian, Antonio F; Felding, Brunhilde H; Ivanisevic, Julijana; Cho, Kevin; Wick, Elizabeth C; Hechenbleikner, Elizabeth M; Uritboonthai, Winnie; Goetz, Laura; Casero, Robert A; Pardoll, Drew M; White, James R; Patti, Gary J; Sears, Cynthia L; Siuzdak, Gary

    2015-06-01

    Bacterial biofilms in the colon alter the host tissue microenvironment. A role for biofilms in colon cancer metabolism has been suggested but to date has not been evaluated. Using metabolomics, we investigated the metabolic influence that microbial biofilms have on colon tissues and the related occurrence of cancer. Patient-matched colon cancers and histologically normal tissues, with or without biofilms, were examined. We show the upregulation of polyamine metabolites in tissues from cancer hosts with significant enhancement of N(1), N(12)-diacetylspermine in both biofilm-positive cancer and normal tissues. Antibiotic treatment, which cleared biofilms, decreased N(1), N(12)-diacetylspermine levels to those seen in biofilm-negative tissues, indicating that host cancer and bacterial biofilm structures contribute to the polyamine metabolite pool. These results show that colonic mucosal biofilms alter the cancer metabolome to produce a regulator of cellular proliferation and colon cancer growth potentially affecting cancer development and progression.

  14. An investigation of the optimization of parameters affecting the implementation of fourier transform spectroscopy at 20-500 micron from the C-141 airborne infrared observatory

    NASA Technical Reports Server (NTRS)

    Thompson, R. I.; Erickson, E. F.

    1976-01-01

    A program for 20-500 micron spectroscopy from the NASA flying C141 infrared observatory is being carried out with a Michelson interferometer. The parameters affecting the performance of the instrument are studied and an optimal configuration for high performance on the C-141 aircraft is recommended. As each parameter is discussed the relative merits of the two modes of mirror motion (rapid scan or step and integrate) are presented.

  15. Inflammatory response in serrated precursor lesions of the colon classified according to WHO entities, clinical parameters and phenotype-genotype correlation.

    PubMed

    Rau, Tilman T; Atreya, Raja; Aust, Daniela; Baretton, Gustavo; Eck, Matthias; Erlenbach-Wünsch, Katharina; Hartmann, Arndt; Lugli, Alessandro; Stöhr, Robert; Vieth, Michael; Wirsing, Anna M; Zlobec, Inti; Katzenberger, Tiemo

    2016-04-01

    Studies on traditional serrated adenoma (TSA) and sessile serrated adenoma with dysplasia (SSA-D) are rare due to the low frequency of these lesions, which are well defined by the latest WHO classification. However, introducing new morphological criteria such as intra-epithelial lymphocytes (IELs) might facilitate colorectal polyp diagnoses. Additionally, the phenotype-genotype correlation needs to be updated as the terminology has repeatedly changed. This study analysed 516 polyps, consisting of 118 classical adenomas (CAD), 116 hyperplastic polyps (HPP), 179 SSAs, 41 SSA-Ds, and 62 TSAs. The lesions were analysed in relation to the patients' clinical parameters including gender, age, localisation, and size. The inflammatory background of the polyps was quantified and BRAF and KRAS mutations as well as MLH1 and CDKN2A promoter methylation were assessed. In multivariate analyses, an increase in IELs was an independent and robust new criterion for the diagnosis of SSA-D (p < 0.001). Superficial erosions and acute neutrophil granulocytes led to reactive changes potentially resembling dysplasia. KRAS and BRAF mutations were associated with CAD/TSA and HPP/SSA, respectively. However, almost half of TSAs had a BRAF mutation and were KRAS wild type. CDKN2A seems to precede MLH1 hyper-methylation within the serrated carcinogenesis model. The genotyping of WHO-based entities - and especially SSA - has sharpened in comparison to previously published data. TSAs can be sub-grouped according to their mutation status. Of note, the higher number of IELs in SSA-D reflects their close relationship to colorectal cancers with micro-satellite instability. Therefore, IELs might represent a new diagnostic tool for SSA-D. PMID:27499921

  16. Evolution of phenotypic plasticity in colonizing species.

    PubMed

    Lande, Russell

    2015-05-01

    I elaborate an hypothesis to explain inconsistent empirical findings comparing phenotypic plasticity in colonizing populations or species with plasticity from their native or ancestral range. Quantitative genetic theory on the evolution of plasticity reveals that colonization of a novel environment can cause a transient increase in plasticity: a rapid initial increase in plasticity accelerates evolution of a new optimal phenotype, followed by slow genetic assimilation of the new phenotype and reduction of plasticity. An association of colonization with increased plasticity depends on the difference in the optimal phenotype between ancestral and colonized environments, the difference in mean, variance and predictability of the environment, the cost of plasticity, and the time elapsed since colonization. The relative importance of these parameters depends on whether a phenotypic character develops by one-shot plasticity to a constant adult phenotype or by labile plasticity involving continuous and reversible development throughout adult life.

  17. Growth and some physiological parameters of four sugar beet (Beta vulgaris l.) cultivars as affected by salinity.

    PubMed

    Khavari-Nejad, R A; Najafi, F; Khavari-Nejad, S

    2008-05-15

    The comparative responses of certain biochemical and physiological characteristics to salinity were studied in 4 cultivars of sugar beet (Beta vulgaris L.) plants. Eight weeks old plants were treated with NaCl at 0, 25 and 50 mM in nutrient solutions. Plants were grown under controlled environment and harvested after 3 weeks for measurements of biochemical and physiological parameters. Results showed that in 25 mM NaCl for cultivars of ET5 and C3-3, soluble sugars in leaves, photosynthetic rate and growth parameters were significantly increased as compared to those of other cultivars. In 50 mM NaCl photosynthetic rate and soluble sugars were significantly increased only in ET5 cultivar as compared with those of others. Results indicated that in 25 mM NaCl, ET5 cultivar showed high growth responses and tolerated to 50 mM NaCl.

  18. Enterohemorrhagic Escherichia coli Colonization of Human Colonic Epithelium In Vitro and Ex Vivo

    PubMed Central

    Lewis, Steven B.; Cook, Vivienne; Tighe, Richard

    2014-01-01

    Enterohemorrhagic Escherichia coli (EHEC) is an important foodborne pathogen causing gastroenteritis and more severe complications, such as hemorrhagic colitis and hemolytic uremic syndrome. Pathology is most pronounced in the colon, but to date there is no direct clinical evidence showing EHEC binding to the colonic epithelium in patients. In this study, we investigated EHEC adherence to the human colon by using in vitro organ culture (IVOC) of colonic biopsy samples and polarized T84 colon carcinoma cells. We show for the first time that EHEC colonizes human colonic biopsy samples by forming typical attaching and effacing (A/E) lesions which are dependent on EHEC type III secretion (T3S) and binding of the outer membrane protein intimin to the translocated intimin receptor (Tir). A/E lesion formation was dependent on oxygen levels and suppressed under oxygen-rich culture conditions routinely used for IVOC. In contrast, EHEC adherence to polarized T84 cells occurred independently of T3S and intimin and did not involve Tir translocation into the host cell membrane. Colonization of neither biopsy samples nor T84 cells was significantly affected by expression of Shiga toxins. Our study suggests that EHEC colonizes and forms stable A/E lesions on the human colon, which are likely to contribute to intestinal pathology during infection. Furthermore, care needs to be taken when using cell culture models, as they might not reflect the in vivo situation. PMID:25534942

  19. Insertion depth of oral stomach tubes may affect the fermentation parameters of ruminal fluid collected in dairy cows.

    PubMed

    Shen, J S; Chai, Z; Song, L J; Liu, J X; Wu, Y M

    2012-10-01

    Six rumen-fistulated dairy cows were used in 2 trials to validate the technique for the collection of ruminal fluid by an oral stomach tube (OST). Trial 1 was conducted to compare the differences of ruminal fermentation parameters among rumen sites (cranial dorsal, cranial ventral, central, ventral, caudal dorsal, and caudal ventral). The ruminal fluid was collected once per day for 3 consecutive days through rumen cannula (RC). The samples were analyzed for pH, volatile fatty acids (VFA), ammonia N, sodium, potassium, calcium, chloride, and phosphorus concentrations. The ruminal fermentation parameters varied significantly among rumen sites. Compared with the central or ventral rumen, the cranial dorsal rumen had significantly higher pH, ammonia, and sodium concentrations and lower acetate, propionate, and butyrate concentrations, indicating that the sampling site may be one of the main factors contributing to the difference in ruminal fermentation parameters between the samples collected via the OST and RC. In trial 2, the fermentation parameters of ruminal fluid collected via OST at 2 insertion depths (180 or 200 cm) were compared with those of ruminal fluid collected via RC (ventral sac). Ruminal fluid was collected once per week at 5 to 6h after morning feeding. When the OST was inserted to a depth of 180 cm, the OST head was located in the cranial dorsal (atrium) of the rumen. The ruminal fluid collected via the OST had higher pH and sodium concentrations but lower VFA, potassium, calcium, and phosphorus concentrations than that collected via RC. However, when the OST was inserted to a depth of 200 cm, the OST head could pass through the front rumen pillar and reach the central rumen for sampling. No differences were found in pH, VFA, ammonia N, and ion concentrations between the samples collected via the 2 sampling methods. These results indicated that the OST should be inserted to reach the central rumen to obtain representative rumen fluid samples.

  20. The role of mechanical properties in cavitation erosion resistance. [parameters affecting metal fatigue under cavitation flow conditions

    NASA Technical Reports Server (NTRS)

    Gould, G. C.

    1974-01-01

    Methods for determining the correlations of erosion resistance and mechanical properties of materials are discussed. The most common method of testing cavitation erosion resistance of materials is the vibratory cavitation probe. The instrument and its operation are described. The use of the whirling arm device is considered as a second method. Metallographic investigations of the earliest stages of cavitation erosion damage of metallic materials was conducted. The materials show plastic deformation occurring during the incubation period and increasing until cracks form and metal fragments are lost. The parameters of the work done to cause material fractures are identified. The reactions obtained with specific materials are reported.

  1. Nitrogen in Hydroponic Growing Medium of Tomato Affects the Demographic Parameters of Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae).

    PubMed

    Hosseini, R S; Madadi, H; Hosseini, M; Delshad, M; Dashti, F

    2015-12-01

    We evaluated the effects of different nitrogen levels (380, 310, 240, and 174 ppm) on the life history parameters of Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) on hydroponically cultured tomato plants. Our data show that there is a positive correlation between the nitrogen content and the demographic parameters, as the intrinsic rate of increase of T. vaporariorum was the lowest (0.059 ± 0.007 day(-1)) at 174 ppm and the highest (0.088 ± 0.005 day(-1)) at 380 ppm of nitrogen. The net reproduction rate (R 0), finite rate of increase (λ), and mean developmental time (T) were significantly influenced by the nitrogen levels. The mean longevity of males and females showed a positive relationship with the nitrogen level, ranging from 64.8 ± 3.96 to 76.3 ± 2.44 for males and 61.6 ± 5.35 to 71.2 ± 2.44 for females, observed in the lowest and highest nitrogen levels, respectively. The relationship between nitrogen fertilization and T. vaporariorum management on tomato crops is discussed.

  2. Nitrogen in Hydroponic Growing Medium of Tomato Affects the Demographic Parameters of Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae).

    PubMed

    Hosseini, R S; Madadi, H; Hosseini, M; Delshad, M; Dashti, F

    2015-12-01

    We evaluated the effects of different nitrogen levels (380, 310, 240, and 174 ppm) on the life history parameters of Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) on hydroponically cultured tomato plants. Our data show that there is a positive correlation between the nitrogen content and the demographic parameters, as the intrinsic rate of increase of T. vaporariorum was the lowest (0.059 ± 0.007 day(-1)) at 174 ppm and the highest (0.088 ± 0.005 day(-1)) at 380 ppm of nitrogen. The net reproduction rate (R 0), finite rate of increase (λ), and mean developmental time (T) were significantly influenced by the nitrogen levels. The mean longevity of males and females showed a positive relationship with the nitrogen level, ranging from 64.8 ± 3.96 to 76.3 ± 2.44 for males and 61.6 ± 5.35 to 71.2 ± 2.44 for females, observed in the lowest and highest nitrogen levels, respectively. The relationship between nitrogen fertilization and T. vaporariorum management on tomato crops is discussed. PMID:26385237

  3. The Importance of Temporal Design: How Do Measurement Intervals Affect the Accuracy and Efficiency of Parameter Estimates in Longitudinal Research?

    PubMed

    Timmons, Adela C; Preacher, Kristopher J

    2015-01-01

    The timing (spacing) of assessments is an important component of longitudinal research. The purpose of the present study is to determine methods of timing the collection of longitudinal data that provide better parameter recovery in mixed effects nonlinear growth modeling. A simulation study was conducted, varying function type, as well as the number of measurement occasions, in order to examine the effect of timing on the accuracy and efficiency of parameter estimates. The number of measurement occasions was associated with greater efficiency for all functional forms and was associated with greater accuracy for the intrinsically nonlinear functions. In general, concentrating measurement occasions toward the left or at the extremes was associated with increased efficiency when estimating the intercepts of intrinsically linear functions, and concentrating values where the curvature of the function was greatest generally resulted in the best recovery for intrinsically nonlinear functions. Results from this study can be used in conjunction with theory to improve the design of longitudinal research studies. In addition, an R program is provided for researchers to run customized simulations to identify optimal sampling schedules for their own research.

  4. Defining Optimal Aerobic Exercise Parameters to Affect Complex Motor and Cognitive Outcomes after Stroke: A Systematic Review and Synthesis

    PubMed Central

    Hasan, S. M. Mahmudul; Rancourt, Samantha N.; Austin, Mark W.; Ploughman, Michelle

    2016-01-01

    Although poststroke aerobic exercise (AE) increases markers of neuroplasticity and protects perilesional tissue, the degree to which it enhances complex motor or cognitive outcomes is unknown. Previous research suggests that timing and dosage of exercise may be important. We synthesized data from clinical and animal studies in order to determine optimal AE training parameters and recovery outcomes for future research. Using predefined criteria, we included clinical trials of stroke of any type or duration and animal studies employing any established models of stroke. Of the 5,259 titles returned, 52 articles met our criteria, measuring the effects of AE on balance, lower extremity coordination, upper limb motor skills, learning, processing speed, memory, and executive function. We found that early-initiated low-to-moderate intensity AE improved locomotor coordination in rodents. In clinical trials, AE improved balance and lower limb coordination irrespective of intervention modality or parameter. In contrast, fine upper limb recovery was relatively resistant to AE. In terms of cognitive outcomes, poststroke AE in animals improved memory and learning, except when training was too intense. However, in clinical trials, combined training protocols more consistently improved cognition. We noted a paucity of studies examining the benefits of AE on recovery beyond cessation of the intervention. PMID:26881101

  5. Detecting the specific parameters that affect the maturation of farmed sea bass (Dicentrarchus labrax) fillets stored in sunflower oil.

    PubMed

    Baygar, Taçnur; Alparslan, Yunus; Okumuş, Melis; Güler, Merve

    2014-06-01

    In this study, it was aimed to detect the specific parameters that effect the maturation of farmed sea bass fillets stored in sunflower oil. Sea bass fillets were taken into the pickling solution (2.5% acetic acid and 11% sodium chloride) at 4 °C(±1). Fish meat in each group was analysed for the following parameters; pH, moisture%, acetic acid% and NaCl% in the maturation pickling solution and in sunflower oil. At the end of the 90 days storage, there were not any negative situations about the fish in terms of the scientific approach. It was detected that the skinless samples had the less NaCl and acidity values but scaly and scaleless samples had the higher values. Main reasons are: for the scaly and scaleless samples, the skin acted as a barrier in the pickling solution or oil and for scaly samples, scales depart from the skin and defeat the passing of NaCl and acid to the meat. When evaluating this study results, the fillet group samples which contain more salt and acetic acid are thought to be more appropriate for marinating in terms of shelf-life and quality. PMID:24876656

  6. Critical rearing parameters of Tetrastichus planipennisi (Hymenoptera: Eulophidae) as affected by host plant substrate and host-parasitoid group structure.

    PubMed

    Duan, Jian J; Oppel, Craig

    2012-06-01

    In laboratory assays, we evaluated the potential impact of host plant substrate types, host-parasitoid group sizes (densities), and parasitoid-to-host ratios on select fitness parameters of the larval endoparasitoid Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae), newly introduced for biological control of emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), in the United States. Results from our study showed that offspring production and critical fitness parameters (body size and sex ratio) of T. planipennisi from parasitized emerald ash borer larvae are significantly influenced by host plant substrate type, host-parasitoid group size, parasitoid-to-host ratio, or a combination in the primary exposure assay. The number of both female and male T. planipennisi progeny was significantly greater when emerald ash borer larvae were inserted into tropical ash [Fraxinus uhdei (Wenz.) Lingelsh.] logs rather than green ash (Fraxinus pensylvanica Marshall). When maintained at a constant 1:1 parasitoid-to-host ratio, assays with larger host-parasitoid group sizes (3:3-12:12) produced significantly greater numbers of both male and female offspring per parental wasp compared with those with the single host-parasitoid (1:1) group treatment. As the parasitoid-to-host ratio increased from 1:1 to 8:1 in the assay, the average brood size (number of offspring per parasitized emerald ash borer larva) increased significantly, whereas the average brood sex ratio (female to male) changed from being female-biased (6:1) to male-biased (1:2); body size of female offspring as measured by the length of ovipositor and left hind tibia also was reduced significantly. Based on these findings, we suggest that the current method of rearing T. planipennisi with artificially infested-emerald ash borer larvae use the tropical ash logs for emerald ash borer insertion, a larger (> or = 3:3) host-parasitoid group size and 1:1 parasitoid-to-host ratio in the primary

  7. Cell colonization in degradable 3D porous matrices

    PubMed Central

    Lawrence, Benjamin J

    2008-01-01

    Cell colonization is an important in a wide variety of biological processes and applications including vascularization, wound healing, tissue engineering, stem cell differentiation and biosensors. During colonization porous 3D structures are used to support and guide the ingrowth of cells into the matrix. In this review, we summarize our understanding of various factors affecting cell colonization in three-dimensional environment. The structural, biological and degradation properties of the matrix all play key roles during colonization. Further, specific scaffold properties such as porosity, pore size, fiber thickness, topography and scaffold stiffness as well as important cell material interactions such as cell adhesion and mechanotransduction also influence colonization. PMID:19262124

  8. Investigating the parameters affecting the adsorption of amino acids onto AgCl nanoparticles with different surface charges.

    PubMed

    Absalan, Ghodratollah; Ghaemi, Maryam

    2012-11-01

    In this paper, adsorption behaviors of typical neutral (alanine), acidic (glutamic acid) and basic (lysine) amino acids onto the surfaces of neutral as well as positively and negatively charged silver chloride nanoparticles were examined. Silver chloride nanoparticles with different charges and different water content were synthesized by reverse micelle method. The adsorptions of the above mentioned amino acids onto the surfaces of differently charged silver chloride nanoparticles were found to depend strongly on various parameters including pH of the aqueous solution, type of amino acid, water to surfactant mole ratio, and type of charges on the surfaces of silver chloride nanoparticles. It was found that the interaction of -NH(3) (+) groups of the amino acids with silver ion could be a driving force for adsorption of amino acids. Alanine and Glutamic acid showed almost similar trend for being adsorbed on the surface of silver chloride nanoparticles. Electrostatic interaction, hydrophobicity of both nanoparticle and amino acid, complex formation between amine group and silver ion, interaction between protonated amine and silver ion as well as the number of nanoparticles per unit volume of solution were considered for interpreting the observed results.

  9. Willingness to Use Microbicides Is Affected by the Importance of Product Characteristics, Use Parameters, and Protective Properties

    PubMed Central

    Morrow, Kathleen M.; Fava, Joseph L.; Rosen, Rochelle K.; Vargas, Sara; Barroso, Candelaria; Christensen, Anna L.; Woodsong, Cynthia; Severy, Lawrence

    2008-01-01

    Background Along with efficacy, a microbicide’s acceptability will be integral to its impact on the pandemic. Understanding Product Characteristics that users find most acceptable and determining who will use which type of product are key to optimizing use effectiveness. Objectives To evaluate psychometrically the Important Microbicide Characteristics (IMC) instrument and examine its relationship to willingness to use microbicides. Results Exploratory and confirmatory factor analyses revealed 2 IMC subscales (Cronbach’s coefficient α: Product Characteristics subscale (α = 0.84) and Protective Properties subscale (α = 0.89)). Significant differences on Product Characteristics subscale scores were found for history of douching (P = 0.002) and employment status (P = 0.001). Whether a woman used a method to prevent pregnancy or sexually transmitted disease (STD) in the last 3 months (P < 0.001) and whether she used a condom during the last vaginal sex episode (P < 0.001) were significantly related to her rating of the importance of microbicides being contraceptive. Product Characteristics (r = 0.21) and Protective Properties (r = 0.27) subscale scores and whether a microbicide had contraceptive properties (r = 0.24) were all significantly associated (P < 0.001) with willingness to use microbicides. Conclusions Formulation and use characteristics and product function(s) affect willingness to use microbicides and should continue to be addressed in product development. The IMC instrument serves as a template for future studies of candidate microbicides. PMID:17325607

  10. Visible Persistence of Single-Transient Random Dot Patterns: Spatial Parameters Affect the Duration of Fading Percepts.

    PubMed

    Bruchmann, Maximilian; Thaler, Kathrin; Vorberg, Dirk

    2015-01-01

    Visible persistence refers to the continuation of visual perception after the physical termination of a stimulus. We studied an extreme case of visible persistence by presenting two matrices of randomly distributed black and white pixels in succession. On the transition from one matrix to the second, the luminance polarity of all pixels within a disk- or annulus-shaped area reversed, physically creating a single second-order transient signal. This transient signal produces the percept of a disk or an annulus with an abrupt onset and a gradual offset. To study the nature of this fading percept we varied spatial parameters, such as the inner and the outer diameter of annuli (Experiment I) and the radius and eccentricity of disks (Experiment III), and measured the duration of visible persistence by having subjects adjust the synchrony of the onset of a reference stimulus with the onset or the offset of the fading percept. We validated this method by comparing two modalities of the reference stimuli (Experiment I) and by comparing the judgments of fading percepts with the judgments of stimuli that actually fade in luminance contrast (Experiment II). The results show that (i) irrespective of the reference modality, participants are able to precisely judge the on- and the offsets of the fading percepts, (ii) auditory reference stimuli lead to higher visible persistence durations than visual ones, (iii) visible persistence duration increases with the thickness of annuli and the diameter of disks, but decreases with the diameter of annuli, irrespective of stimulus eccentricity. These effects cannot be explained by stimulus energy, which suggests that more complex processing mechanisms are involved. Seemingly contradictory effects of disk and annulus diameter can be unified by assuming an abstract filling-in mechanism that speeds up with the strength of the edge signal and takes more time the larger the stimulus area is.

  11. Water-borne diclofenac affects kidney and gill integrity and selected immune parameters in brown trout (Salmo trutta f. fario).

    PubMed

    Hoeger, Birgit; Köllner, Bernd; Dietrich, Daniel R; Hitzfeld, Bettina

    2005-10-01

    health of affected fish populations.

  12. Generation of 4-hydroxy-2,5-dimethyl-3(2H)-furanone from rhamnose as affected by reaction parameters: experimental design approach.

    PubMed

    Illmann, Silke; Davidek, Tomas; Gouézec, Elisabeth; Rytz, Andreas; Schuchmann, Heike P; Blank, Imre

    2009-04-01

    The formation of 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF) was studied in aqueous model systems containing L-rhamnose and L-lysine. The approach consisted in systematically varying four reaction parameters (rhamnose concentration, rhamnose to lysine ratio, pH, and phosphate concentration) at 3 levels. A fractional factorial design was used to reduce the number of trials. The degradation of rhamnose was followed by high performance anion exchange chromatography and the formation of HDMF by solid phase extraction in combination with GC/MS. The study permitted the identification of critical reaction parameters that affect the formation of HDMF from rhamnose in aqueous systems. Although all studied parameters have some impact on the HDMF formation and rhamnose degradation kinetics, the effect of phosphate is by far the most important, followed by concentration of precursors and pH. The experimental design approach permitted us, with a limited number of experiments, to accurately model the effects of the four investigated reaction parameters on the kinetics of rhamnose degradation and HDMF formation (R(2)>0.93). Overall, the results indicate that rhamnose can be an excellent precursor of HDMF (yield >40 mol%), if the reaction conditions are well mastered. PMID:19256512

  13. Colon cancer screening

    MedlinePlus

    Screening for colon cancer; Colonoscopy - screening; Sigmoidoscopy - screening; Virtual colonoscopy - screening; Fecal immunochemical test; Stool DNA test; sDNA test; Colorectal cancer - screening; Rectal ...

  14. Bacterial Colonization of Particles: Growth and Interactions

    PubMed Central

    Grossart, Hans-Peter; Kiørboe, Thomas; Tang, Kam; Ploug, Helle

    2003-01-01

    Marine particles in the ocean are exposed to diverse bacterial communities, and colonization and growth of attached bacteria are important processes in the degradation and transformation of the particles. In an earlier study, we showed that the initial colonization of model particles by individual bacterial strains isolated from marine aggregates was a function of attachment and detachment. In the present study, we have investigated how this colonization process was further affected by growth and interspecific interactions among the bacteria. Long-term incubation experiments showed that growth dominated over attachment and detachment after a few hours in controlling the bacterial population density on agar particles. In the absence of grazing mortality, this growth led to an equilibrium population density consistent with the theoretical limit due to oxygen diffusion. Interspecific interaction experiments showed that the presence of some bacterial strains (“residents”) on the agar particles either increased or decreased the colonization rate of other strains (“newcomers”). Comparison between an antibiotic-producing strain and its antibiotic-free mutant showed no inhibitory effect on the newcomers due to antibiotic production. On the contrary, hydrolytic activity of the antibiotic-producing strain appeared to benefit the newcomers and enhance their colonization rate. These results show that growth- and species-specific interactions have to be taken into account to adequately describe bacterial colonization of marine particles. Changes in colonization pattern due to such small-scale processes may have profound effects on the transformation and fluxes of particulate matter in the ocean. PMID:12788756

  15. Bacterial colonization of particles: growth and interactions.

    PubMed

    Grossart, Hans-Peter; Kiørboe, Thomas; Tang, Kam; Ploug, Helle

    2003-06-01

    Marine particles in the ocean are exposed to diverse bacterial communities, and colonization and growth of attached bacteria are important processes in the degradation and transformation of the particles. In an earlier study, we showed that the initial colonization of model particles by individual bacterial strains isolated from marine aggregates was a function of attachment and detachment. In the present study, we have investigated how this colonization process was further affected by growth and interspecific interactions among the bacteria. Long-term incubation experiments showed that growth dominated over attachment and detachment after a few hours in controlling the bacterial population density on agar particles. In the absence of grazing mortality, this growth led to an equilibrium population density consistent with the theoretical limit due to oxygen diffusion. Interspecific interaction experiments showed that the presence of some bacterial strains ("residents") on the agar particles either increased or decreased the colonization rate of other strains ("newcomers"). Comparison between an antibiotic-producing strain and its antibiotic-free mutant showed no inhibitory effect on the newcomers due to antibiotic production. On the contrary, hydrolytic activity of the antibiotic-producing strain appeared to benefit the newcomers and enhance their colonization rate. These results show that growth- and species-specific interactions have to be taken into account to adequately describe bacterial colonization of marine particles. Changes in colonization pattern due to such small-scale processes may have profound effects on the transformation and fluxes of particulate matter in the ocean.

  16. Acute administration of 3,5-diiodo-L-thyronine to hypothyroid rats affects bioenergetic parameters in rat skeletal muscle mitochondria.

    PubMed

    Lombardi, Assunta; Lanni, Antonia; de Lange, Pieter; Silvestri, Elena; Grasso, Paola; Senese, Rosalba; Goglia, Fernando; Moreno, Maria

    2007-12-22

    We investigated the mechanism by which 3,5-diiodo-l-thyronine (T2) affects skeletal muscle mitochondrial bioenergetic parameters following its acute administration to hypothyroid rats. One hour after injection, T2 increased both coupled and uncoupled respiration rates by +27% and +42%, respectively. Top-down elasticity analysis revealed that these effects were the result of increases in the substrate oxidation and mitochondrial uncoupling. Discriminating between proton-leak and redox-slip processes, we identified an increased mitochondrial proton conductance as the "pathway" underlying the effect of T2 on mitochondrial uncoupling. As a whole, these results may provide a mechanism by which T2 rapidly affects energy metabolism in hypothyroid rats.

  17. Dehydropeptidase 1 promotes metastasis through regulation of E-cadherin expression in colon cancer

    PubMed Central

    Park, Sang Yoon; Lee, Seon-Jin; Cho, Hee Jun; Kim, Tae Woo; Kim, Jong-Tae; Kim, Jae Wha; Lee, Chul-Ho; Kim, Bo-Yeon; Yeom, Young Il; Lim, Jong-Seok; Lee, Younghee; Lee, Hee Gu

    2016-01-01

    Dehydropeptidase 1 (DPEP1) is a zinc-dependent metalloproteinase that is expressed aberrantly in several cancers. The role of DPEP1 in cancer remain controversial. In this study, we demonstrate that DPEP1 functions as a positive regulator for colon cancer cell metastasis. The expression of DPEP1 mRNA and proteins were upregulated in colon cancer tissues compared to normal mucosa. Gain-of-function and loss-of-function approaches were used to examine the malignant phenotype of DPEP1-expressing or DPEP1-depleted cells. DPEP1 expression caused a significant increase in colon cancer cell adhesion and invasion in vitro, and metastasis in vivo. In contrast, DPEP1 depletion induced opposite effects. Furthermore, cilastatin, a DPEP1 inhibitor, suppressed the invasion and metastasis of DPEP1-expressing cells. DPEP1 inhibited the leukotriene D4 signaling pathway and increased the expression of E-cadherin. We also show that DPEP1 mediates TGF-β-induced EMT. TGF-β transcriptionally repressed DPEP1 expression. TGF-β treatment decreased E-cadherin expression and promoted cell invasion in DPEP1-expressing colon cancer cell lines, whereas it did not affect these parameters in DPEP1-depleted cell lines. These results suggest that DPEP1 promotes cancer metastasis by regulating E-cadherin plasticity and that it might be a potential therapeutic target for preventing the progression of colon cancer. PMID:26824987

  18. Giant colonic diverticulum: radiographic and MDCT characteristics.

    PubMed

    Zeina, Abdel-Rauf; Mahamid, Ahmad; Nachtigal, Alicia; Ashkenazi, Itamar; Shapira-Rootman, Mika

    2015-12-01

    Giant colonic diverticulum (GCD), defined as a diverticulum larger than 4 cm, is a rare entity that is generally a manifestation of colonic diverticular disease. Because of its rarity and its variable and non-specific presentation, the diagnosis of GCD depends mainly on imaging findings. Knowledge of the spectrum of radiographic and CT features of the GCD is important in making the correct diagnosis and potentially preventing complications. This review focuses on imaging findings characteristic of GCD as well as its complications and radiographic mimics. Teaching points • Giant colonic diverticulum is a rare complication of diverticulosis.• The most common symptom is abdominal pain presenting in approximately 70 % of patients.• Diagnosis is based on imaging findings with plain abdominal radiographs and MDCT.• Treatment consists of en bloc resection of the diverticulum and affected adjacent colon.

  19. Treatment with D-penicillamine or zinc sulphate affects copper metabolism and improves but not normalizes antioxidant capacity parameters in Wilson disease.

    PubMed

    Gromadzka, Grażyna; Grażyna, Gromadzka; Karpińska, Agata; Agata, Karpińska; Przybyłkowski, Adam; Adam, Przybyłkowski; Litwin, Tomasz; Tomasz, Litwin; Wierzchowska-Ciok, Agata; Agata, Wierzchowska-Ciok; Dzieżyc, Karolina; Karolina, Dzieżyc; Chabik, Grzegorz; Grzegorz, Chabik; Członkowska, Anna; Anna, Członkowska

    2014-02-01

    Copper accumulation in tissues due to a biallelic pathogenic mutation of the gene: ATP7B results in a clinical phenotype known as Wilson disease (WD). Aberrations in copper homeostasis can create favourable conditions for superoxide-yielding redox cycling and oxidative tissue damage. Drugs used in WD treatment aim to remove accumulated copper and normalise the free copper concentration in the blood. In the current study the effect of decoppering treatment on copper metabolism and systemic antioxidant capacity parameters was analyzed. Treatment naïve WD patients (TNWD) (n = 33), those treated with anti-copper drugs (TWD) (n = 99), and healthy controls (n = 99) were studied. Both TNWD and TWD patients characterised with decreased copper metabolism parameters, as well as decreased total antioxidant potential (AOP), glutathione (GSH) level, activity of catalase, glutathione peroxidase (GPx), and S-transferase glutathione, compared to controls. TWD patients had significantly lower copper metabolism parameters, higher total AOP and higher levels of GSH than TWD individuals; however, no difference was observed between these two patient groups with respect to the rest of the antioxidant capacity parameters. Patients who had undergone treatment with D-penicillamine or zinc sulphate did not differ with respect to copper metabolism or antioxidant capacity parameters, with the exception of GPx that was lower in D-penicillamine treated individuals. These data suggest that anti-copper treatment affects copper metabolism as well as improves, but does not normalize, natural antioxidant capacity in patients with WD. We propose to undertake studies aimed to evaluate the usefulness of antioxidants as well as selenium as a supplemental therapy in WD.

  20. Clinical significance of HOTAIR expression in colon cancer

    PubMed Central

    Luo, Zhi-Fen; Zhao, Dan; Li, Xi-Qing; Cui, Yong-Xia; Ma, Ning; Lu, Chuang-Xin; Liu, Ming-Yue; Zhou, Yun

    2016-01-01

    AIM: To detect the expression of the long noncoding RNA HOTAIR in colon cancer and analyze its relationship with clinicopathological parameters of colon cancer. METHODS: Total RNA was extracted from 80 colon cancer tissues and matched tumor-adjacent normal colon tissues and reverse transcribed. Quantitative polymerase chain reaction was used to detect the expression of HOTAIR. The relationship between the expression of HOTAIR and clinicopathological parameters of colon cancer was analyzed. RESULTS: The expression of HOTAIR was significantly higher in colon cancer tissues than in matched tumor-adjacent normal colon tissues (P < 0.05). HOTAIR expression was significantly higher in cases with lymph node metastasis than in those without metastasis; in lowly differentiated and undifferentiated cases than in highly and moderately differentiated cases; and in stages III + IV cases than in stages I + II cases (P < 0.05). CONCLUSION: HOTAIR expression is upregulated in colon cancer, suggesting that HOTAIR plays an important role in the tumorigenesis, development and metastasis of colon cancer. HOTAIR may act as an oncogene and represents a new molecular target for the treatment of colon cancer. PMID:27298568

  1. Radionuclide transit in patients with colon interposition

    SciTech Connect

    Isolauri, J.; Koskinen, M.O.; Markkula, H.

    1987-10-01

    To assess radionuclide transit in interposed segments of the colon, we examined 25 patients with colon interposition for benign esophageal disease. No such assessment has been reported previously. The most common indications for operation were esophageal strictures that developed after lye ingestion and reflux strictures not responding to other treatment. The operations were performed without thoracotomy by blunt esophageal dissection in 80% of the patients. There were 18 antiperistaltic and seven isoperistaltic colon grafts. A large-field gamma camera and computer system were used. Data were collected at time intervals of 0.5 second during the first 30 seconds and at intervals of 30 seconds up to 20 minutes. The 5% and 90% stomach filling times, times to 50% and 25% activity levels, and residual activity levels as a percentage of the maxima were calculated in the upper, middle, and lower thirds of the colon grafts and of the normal esophagus of 10 healthy control subjects. The examinations were performed with the subject in a sitting position. All parameters showed that emptying of the colon graft was markedly slower than that of the normal esophagus. The intra-abdominal third of the graft had a residual activity of 50.5% +/- 15.7% after 20 minutes' observation. No differences between antiperistaltic and isoperistaltic grafts were observed. Reconstruction with proximal cologastric anastomosis and a short intra-abdominal colon graft segments is suggested.

  2. Giant colon diverticulum.

    PubMed

    Chater, C; Saudemont, A; Zerbib, P

    2015-11-01

    Giant colonic diverticulum is defined by a diverticulum whose diameter is greater than 4 cm. This is a rare entity, arising mainly in the sigmoid colon. The diagnosis is based on abdominal computed tomography that shows a gas-filled structure communicating with the adjacent colon, with a smooth, thin diverticular wall that does not enhance after injection of contrast. Surgical treatment is recommended even in asymptomatic diverticula, due to the high prevalence and severity of complications. The gold standard treatment is segmental colectomy. Some authors propose a diverticulectomy when the giant diverticulum is unique.

  3. Lunar Colonization and NASA's Exploration Changes

    NASA Astrophysics Data System (ADS)

    Gavert, Raymond B.

    2006-01-01

    Space colonization is not part of NASA's mission planning. NASA's exploration vision, mission goals and program implementations, however, can have an important affect on private lunar programs leading towards colonization. NASA's exploration program has been described as a journey not a race. It is not like the Apollo mission having tight schedules and relatively unchanging direction. NASA of this era has competing demands from the areas of aeronautics, space science, earth science, space operations and, there are competing demands within the exploration program itself. Under the journey not a race conditions, an entrepreneur thinking about building a hotel on the Moon, with a road to an exploration site, might have difficulty determining where and when NASA might be at a particular place on the Moon. Lunar colonization advocates cannot depend on NASA or other nations with space programs to lead the way to colonization. They must set their own visions, mission goals and schedules. In implementing their colonization programs they will be resource limited. They would be like ``hitchhikers'' following the programs of spacefaring nations identifying programs that might have a fit with their vision and be ready to switch to other programs that may take them in the colonization direction. At times they will have to muster their own limited resources and do things themselves where necessary. The purpose of this paper is to examine current changes within NASA, as a lunar colonization advocate might do, in order to see where there might be areas for fitting into a lunar colonization strategy. The approach will help understand how the ``hitchhiking'' technique might be better utilized.

  4. Colonic diverticulitis in adolescents: an index case and associated syndromes.

    PubMed

    Santin, Brian J; Prasad, Vinay; Caniano, Donna A

    2009-10-01

    Diverticular disease of the colon, a common problem among adults, is diagnosed rarely in children. We report an adolescent patient with sigmoid diverticulitis who required operative treatment. Pediatric patients with the complications of diverticula typically have conditions that result in genetic alterations affecting the components of the colonic wall. Our patient had Williams-Beuren syndrome, although Ehlers-Danlos syndrome, Marfan syndrome, and cystic fibrosis may also be associated with colonic diverticula in adolescence. Pediatric patients with these disorders who experience abdominal pain should be evaluated for the presence of colonic diverticular complications. PMID:19711089

  5. Investigating how fundamental parameters of XRF sample preparation and analysis affect the observed elemental concentration: an experiment using fluvial sediment from Sabah, Borneo.

    NASA Astrophysics Data System (ADS)

    Higton, Sam; Walsh, Rory

    2015-04-01

    X-Ray Fluorescence (XRF) is an important technique for measuring the concentrations of geochemical elements and inorganic contaminants adsorbed to sediments as an input to sediment tracing methods used to evaluate sediment transport dynamics in river catchments. In addition to traditional laboratory-based XRF instruments, the advent of increasingly advanced portable handheld XRF devices now mean that samples of fluvial sediment can be analysed in the field or in the laboratory following appropriate sample preparation procedures. There are limitations and sources of error associated with XRF sample preparation and analysis, however. It is therefore important to understand how fundamental parameters involved in sample preparation and analysis, such as sample compression and measurement exposure duration, affect observed variability in measurement results. Such considerations become important if the resulting measurement variability is high relative to the natural variability in element concentrations at a sample site. This paper deployed a simple experimental design to assess the impacts of varying a number of sample preparation and XRF analysis parameters on recorded measurements of elemental concentrations of the fine fraction (<63um) of bed-sediment samples. Specifically the study compared observed elemental concentrations measured using a Rigaku NEX-CG laboratory machine versus a handheld Niton XL3t-900 XRF elemental analyser. Helium purging was used on both machines to enable measurement of lighter geochemical elements. Sediment sub-samples were taken from a larger homogenised sample from a sediment core taken from an in-channel lateral bench deposit of the Brantian river in Sabah, Borneo; the core site is being used for research into multi-proxy sediment fingerprinting as part of the Stability of Altered Forest Ecosystems (SAFE) project. Some fundamental sample preparation procedures consistent with US EPA Method 6200 were applied to all sediment samples in

  6. Does the antibiotic amoxicillin affect haemocyte parameters in non-target aquatic invertebrates? The clam Ruditapes philippinarum and the mussel Mytilus galloprovincialis as model organisms.

    PubMed

    Matozzo, Valerio; Bertin, Valeria; Battistara, Margherita; Guidolin, Angelica; Masiero, Luciano; Marisa, Ilaria; Orsetti, Alessandro

    2016-08-01

    Amoxicillin (AMX) is one of the most widely used antibiotics worldwide, and its levels in aquatic ecosystems are expected to be detectable. At present, information concerning the toxic effects of AMX on non-target aquatic organisms, such as bivalves, is scarce. Consequently, in this study, we investigated for the first time the effects of AMX on the haemocyte parameters of two bivalve species, the clam Ruditapes philippinarum and the mussel Mytilus galloprovincialis, which share the same habitat in the Lagoon of Venice, in order to compare the relative sensitivity of the two species. The bivalves were exposed to 100, 200 and 400 μg AMX/L for 1, 3 and 7 days, and the effects on the total haemocyte count (THC), the diameter and volume of the haemocytes, haemocyte proliferation, lactate dehydrogenase (LDH) activity in cell-free haemolymph, the haemolymph pH, and the formation of micronuclei were evaluated. The actual concentrations of AMX in the seawater samples from the experimental tanks were also measured. Overall, the obtained results demonstrated that AMX affected slightly the haemocyte parameters of bivalves. In addition, no clear differences in terms of sensitivity to AMX exposure were recorded between the two bivalve species.

  7. Does the antibiotic amoxicillin affect haemocyte parameters in non-target aquatic invertebrates? The clam Ruditapes philippinarum and the mussel Mytilus galloprovincialis as model organisms.

    PubMed

    Matozzo, Valerio; Bertin, Valeria; Battistara, Margherita; Guidolin, Angelica; Masiero, Luciano; Marisa, Ilaria; Orsetti, Alessandro

    2016-08-01

    Amoxicillin (AMX) is one of the most widely used antibiotics worldwide, and its levels in aquatic ecosystems are expected to be detectable. At present, information concerning the toxic effects of AMX on non-target aquatic organisms, such as bivalves, is scarce. Consequently, in this study, we investigated for the first time the effects of AMX on the haemocyte parameters of two bivalve species, the clam Ruditapes philippinarum and the mussel Mytilus galloprovincialis, which share the same habitat in the Lagoon of Venice, in order to compare the relative sensitivity of the two species. The bivalves were exposed to 100, 200 and 400 μg AMX/L for 1, 3 and 7 days, and the effects on the total haemocyte count (THC), the diameter and volume of the haemocytes, haemocyte proliferation, lactate dehydrogenase (LDH) activity in cell-free haemolymph, the haemolymph pH, and the formation of micronuclei were evaluated. The actual concentrations of AMX in the seawater samples from the experimental tanks were also measured. Overall, the obtained results demonstrated that AMX affected slightly the haemocyte parameters of bivalves. In addition, no clear differences in terms of sensitivity to AMX exposure were recorded between the two bivalve species. PMID:27219711

  8. Transverse colon conduit diversion

    SciTech Connect

    Schmidt, J.D.; Buchsbaum, H.J.

    1986-05-01

    The versatility and other advantages of the transverse colon conduit for urinary diversion have been described and implemented in 50 patients. Because most patients considered for this procedure will be at high risk because of a history of significant pelvic irradiation, underlying malignancy, poor renal function, fistula, and so forth, the technical details of surgery and patient selection cannot be minimized. The transverse colon segment is indicated for primary supravesical diversion as well as for salvage of problems related to ileal conduits. Adenocarcinoma of the colon is an unlikely long-term complication of this form of diversion because the fecal stream is absent. Now that the transverse colon conduit has been used for more than 10 years, meaningful comparisons with ileal segments should soon be available.

  9. Laparoscopic Colon Resection

    MedlinePlus

    ... inches to complete the procedure. What are the Advantages of Laparoscopic Colon Resection? Results may vary depending ... type of procedure and patient’s overall condition. Common advantages are: Less postoperative pain May shorten hospital stay ...

  10. Nutraceuticals as potential therapeutic agents for colon cancer: a review

    PubMed Central

    Kuppusamy, Palaniselvam; Yusoff, Mashitah M.; Maniam, Gaanty Pragas; Ichwan, Solachuddin Jauhari Arief; Soundharrajan, Ilavenil; Govindan, Natanamurugaraj

    2014-01-01

    Colon cancer is a world-wide health problem and the second-most dangerous type of cancer, affecting both men and women. The modern diet and lifestyles, with high meat consumption and excessive alcohol use, along with limited physical activity has led to an increasing mortality rate for colon cancer worldwide. As a result, there is a need to develop novel and environmentally benign drug therapies for colon cancer. Currently, nutraceuticals play an increasingly important role in the treatment of various chronic diseases such as colon cancer, diabetes and Alzheimer׳s disease. Nutraceuticals are derived from various natural sources such as medicinal plants, marine organisms, vegetables and fruits. Nutraceuticals have shown the potential to reduce the risk of colon cancer and slow its progression. These dietary substances target different molecular aspects of colon cancer development. Accordingly, this review briefly discusses the medicinal importance of nutraceuticals and their ability to reduce the risk of colorectal carcinogenesis. PMID:26579381

  11. Colonization and epithelial adhesion in the pathogenesis of neonatal candidiasis.

    PubMed

    Bendel, Catherine M

    2003-10-01

    Candida species are important nosocomial pathogens in the newborn population, particularly among the premature very-low-birth-weight infants in neonatal intensive care units. Candida colonization of the neonatal skin and gastrointestinal tract is an important first step in the pathogenesis of invasive disease. C albicans is the most commonly isolated species in colonized or infected infants. Over the past decade the incidence of both colonization and infection with other Candida species, particularly C parapsilosis, has risen dramatically. Colonization of the infant occurs early in life and is affected by a variety of common practices in neonatal intensive care. Microbial factors also augment colonization, including the ability of Candida to adhere to human epithelium. A better understanding of the complex interactions between host risk factors and virulence traits of colonizing yeast may allow the risk of systemic spread to be reduced in the population of premature infants.

  12. Intestinal colonization resistance

    PubMed Central

    Lawley, Trevor D; Walker, Alan W

    2013-01-01

    Dense, complex microbial communities, collectively termed the microbiota, occupy a diverse array of niches along the length of the mammalian intestinal tract. During health and in the absence of antibiotic exposure the microbiota can effectively inhibit colonization and overgrowth by invading microbes such as pathogens. This phenomenon is called ‘colonization resistance’ and is associated with a stable and diverse microbiota in tandem with a controlled lack of inflammation, and involves specific interactions between the mucosal immune system and the microbiota. Here we overview the microbial ecology of the healthy mammalian intestinal tract and highlight the microbe–microbe and microbe–host interactions that promote colonization resistance. Emerging themes highlight immunological (T helper type 17/regulatory T-cell balance), microbiota (diverse and abundant) and metabolic (short-chain fatty acid) signatures of intestinal health and colonization resistance. Intestinal pathogens use specific virulence factors or exploit antibiotic use to subvert colonization resistance for their own benefit by triggering inflammation to disrupt the harmony of the intestinal ecosystem. A holistic view that incorporates immunological and microbiological facets of the intestinal ecosystem should facilitate the development of immunomodulatory and microbe-modulatory therapies that promote intestinal homeostasis and colonization resistance. PMID:23240815

  13. Enhanced attachment of Bradyrhizobium japonicum to soybean through reduced root colonization of internally seedborne microorganisms.

    PubMed

    Oehrle, N W; Karr, D B; Kremer, R J; Emerich, D W

    2000-07-01

    Internally seedborne microorganisms are those surviving common surface sterilization procedures. Such microbes often colonize the radicle surface of a germinating soybean (Glycine max) seed, introducing an undefined parameter into studies on attachment and infection by Bradyrhizobium japonicum. Bacterial isolates from surface-sterilized soybean seed, cv. Williams 82 and cv. Maverick, used in our studies, were identified as Agrobacterium radiobacter, Aeromonas sp., Bacillus spp., Chryseomonas luteola, Flavimonas oryzihabitans, and Sphingomonas paucimobilis. Growth of these microbes during seed germination was reduced by treating germinating seeds with 500 micrograms/mL penicillin G. The effects of this antibiotic on seedling development and on B. japonicum 2143 attachment, nodulation, and nitrogen fixation are reported here. Penicillin G treatment of seeds did not reduce seed germination or root tip growth, or affect seedling development. No differences in nodulation kinetics, nitrogen fixation onset or rates were observed. However, the number of B. japonicum attached to treated intact seedlings was enhanced 200-325%, demonstrating that other root-colonizing bacteria can interfere with rhizobial attachment. Penicillin G treatment of soybean seedlings can be used to reduce the root colonizing microbes, which introduce an undefined parameter into studies of attachment of B. japonicum to the soybean root, without affecting plant development.

  14. Cathelicidin suppresses colon cancer development by inhibition of cancer associated fibroblasts

    PubMed Central

    Cheng, Michelle; Ho, Samantha; Yoo, Jun Hwan; Tran, Deanna Hoang-Yen; Bakirtzi, Kyriaki; Su, Bowei; Tran, Diana Hoang-Ngoc; Kubota, Yuzu; Ichikawa, Ryan; Koon, Hon Wai

    2015-01-01

    Background Cathelicidin (LL-37 in humans and mCRAMP in mice) represents a family of endogenous antimicrobial and anti-inflammatory peptides. Cancer-associated fibroblasts can promote the proliferation of colon cancer cells and growth of colon cancer tumors. Methods We examined the role of cathelicidin in the development of colon cancer, using subcutaneous human HT-29 colon-cancer-cell-derived tumor model in nude mice and azoxymethane- and dextran sulfate-mediated colon cancer model in C57BL/6 mice. We also determined the indirect antitumoral mechanism of cathelicidin via the inhibition of epithelial–mesenchymal transition (EMT) of colon cancer cells and fibroblast-supported colon cancer cell proliferation. Results Intravenous administration of cathelicidin expressing adeno-associated virus significantly reduced the size of tumors, tumor-derived collagen expression, and tumor-derived fibroblast expression in HT-29-derived subcutaneous tumors in nude mice. Enema administration of the mouse cathelicidin peptide significantly reduced the size and number of colonic tumors in azoxymethane- and dextran sulfate-treated mice without inducing apoptosis in tumors and the adjacent normal colonic tissues. Cathelicidin inhibited the collagen expression and vimentin-positive fibroblast expression in colonic tumors. Cathelicidin did not directly affect HT-29 cell viability, but did significantly reduce tumor growth factor-β1-induced EMT of colon cancer cells. Media conditioned by the human colonic CCD-18Co fibroblasts promoted human colon cancer HT-29 cell proliferation. Cathelicidin pretreatment inhibited colon cancer cell proliferation mediated by media conditioned by human colonic CCD-18Co fibroblasts. Cathelicidin disrupted tubulin distribution in colonic fibroblasts. Disruption of tubulin in fibroblasts reduced fibroblast-supported colon cancer cell proliferation. Conclusion Cathelicidin effectively inhibits colon cancer development by interfering with EMT and fibroblast

  15. CT evaluation of the colon: inflammatory disease.

    PubMed

    Horton, K M; Corl, F M; Fishman, E K

    2000-01-01

    Computed tomography (CT) is valuable for detection and characterization of many inflammatory conditions of the colon. At CT, a dilated, thickened appendix is suggestive of appendicitis. A 1-4-cm, oval, fatty pericolic lesion with surrounding mesenteric inflammation is diagnostic of epiploic appendagitis. The key to distinguishing diverticulitis from other inflammatory conditions of the colon is the presence of diverticula in the involved segment. In typhlitis, CT demonstrates cecal distention and circumferential thickening of the cecal wall, which may have low attenuation secondary to edema. In radiation colitis, the clinical history is the key to suggesting the diagnosis because the CT findings can be nonspecific. The location of the involved segment and the extent and appearance of wall thickening may help distinguish Crohn disease and ulcerative colitis. In ischemic colitis, CT typically demonstrates circumferential, symmetric wall thickening with fold enlargement. CT findings of graft-versus-host disease include small bowel and colonic wall thickening, which may result in luminal narrowing and separation of bowel loops. In infectious colitis, the site and thickness of colon affected may suggest a specific organism. The amount of wall thickening in pseudomembranous colitis is typically greater than in any other inflammatory disease of the colon except Crohn disease. PMID:10715339

  16. Management of the colonic volvulus in 2016.

    PubMed

    Perrot, L; Fohlen, A; Alves, A; Lubrano, J

    2016-06-01

    Colonic volvulus is the third leading cause of colonic obstruction worldwide, occurring at two principal locations: the sigmoid colon and cecum. In Western countries, sigmoid volvulus preferentially affects elderly men whereas cecal volvulus affects younger women. Some risk factors, such as chronic constipation, high-fiber diet, frequent use of laxatives, personal past history of laparotomy and anatomic predispositions, are common to both locations. Clinical symptomatology is non-specific, including a combination of abdominal pain, gaseous distention, and bowel obstruction. Abdominopelvic computerized tomography is currently the gold standard examination, allowing positive diagnosis as well as detection of complications. Specific management depends on the location, patient comorbidities and colonic wall viability, but treatment is an emergency in every case. If clinical or radiological signs of gravity are present, emergency surgery is mandatory, but is associated with high morbidity and mortality rates. For sigmoid volvulus without criteria of gravity, the ideal strategy is an endoscopic detorsion procedure followed, within 2 to 5 days, by surgery that includes a sigmoid colectomy with primary anastomosis. Exclusively endoscopic therapy must be reserved for patients who are at excessive risk for surgical intervention. In cecal volvulus, endoscopy has no role and surgery is the rule. PMID:27132752

  17. Understanding your colon cancer risk

    MedlinePlus

    Colon cancer risk factors are things that increase the chance that you could get cancer. Some risk factors ... risk factors never get cancer. Other people get colon cancer but do not have any known risk factors. ...

  18. Streptococcus Adherence and Colonization

    PubMed Central

    Nobbs, Angela H.; Lamont, Richard J.; Jenkinson, Howard F.

    2009-01-01

    Summary: Streptococci readily colonize mucosal tissues in the nasopharynx; the respiratory, gastrointestinal, and genitourinary tracts; and the skin. Each ecological niche presents a series of challenges to successful colonization with which streptococci have to contend. Some species exist in equilibrium with their host, neither stimulating nor submitting to immune defenses mounted against them. Most are either opportunistic or true pathogens responsible for diseases such as pharyngitis, tooth decay, necrotizing fasciitis, infective endocarditis, and meningitis. Part of the success of streptococci as colonizers is attributable to the spectrum of proteins expressed on their surfaces. Adhesins enable interactions with salivary, serum, and extracellular matrix components; host cells; and other microbes. This is the essential first step to colonization, the development of complex communities, and possible invasion of host tissues. The majority of streptococcal adhesins are anchored to the cell wall via a C-terminal LPxTz motif. Other proteins may be surface anchored through N-terminal lipid modifications, while the mechanism of cell wall associations for others remains unclear. Collectively, these surface-bound proteins provide Streptococcus species with a “coat of many colors,” enabling multiple intimate contacts and interplays between the bacterial cell and the host. In vitro and in vivo studies have demonstrated direct roles for many streptococcal adhesins as colonization or virulence factors, making them attractive targets for therapeutic and preventive strategies against streptococcal infections. There is, therefore, much focus on applying increasingly advanced molecular techniques to determine the precise structures and functions of these proteins, and their regulatory pathways, so that more targeted approaches can be developed. PMID:19721085

  19. The role of colonic metabolism in lactose intolerance.

    PubMed

    He, T; Venema, K; Priebe, M G; Welling, G W; Brummer, R-J M; Vonk, R J

    2008-08-01

    Lactose maldigestion and intolerance affect a large part of the world population. The underlying factors of lactose intolerance are not fully understood. In this review, the role of colonic metabolism is discussed, i.e. fermentation of lactose by the colonic microbiota, colonic processing of the fermentation metabolites and how these processes would play a role in the pathophysiology of lactose intolerance. We suggest that the balance between the removal and production rate of osmotic-active components (lactose, and intermediate metabolites, e.g. lactate, succinate, etc.) in the colon is a key factor in the development of symptoms. The involvement of the colon may provide the basis for designing new targeted strategies for dietary and clinical management of lactose intolerance.

  20. Detection of colon cancer by terahertz techniques

    NASA Astrophysics Data System (ADS)

    Wahaia, Faustino; Valusis, Gintaras; Bernardo, Luis M.; Almeida, Abílio; Moreira, J. Agostinho; Lopes, Patricia C.; Macutkevic, Jan; Kasalynas, Irmantas; Seliuta, Dalius; Adomavicius, Ramunas; Henrique, Rui; Lopes, Machado

    2011-05-01

    Normal and cancer affected samples of colon tissue have been measured using transmission time-domain terahertz spectroscopy and continuous wave terahertz imaging. We show that it is possible to distinguish between normal and cancerous regions in the samples when they are fixed in formalin or embedded in paraffin. Plots of the refractive index of normal and cancer affected tissues as well as 2-D transmission THz images are shown. Experimental results will be presented and the conditions for discrimination between normal and affected tissue will be discussed.

  1. Salmonella induces prominent gene expression in the rat colon

    PubMed Central

    Rodenburg, Wendy; Keijer, Jaap; Kramer, Evelien; Roosing, Susanne; Vink, Carolien; Katan, Martijn B; van der Meer, Roelof; Bovee-Oudenhoven, Ingeborg MJ

    2007-01-01

    Background Salmonella enteritidis is suggested to translocate in the small intestine. In vivo it induces gene expression changes in the ileal mucosa and Peyer's patches. Stimulation of Salmonella translocation by dietary prebiotics fermented in colon suggests involvement of the colon as well. However, effects of Salmonella on colonic gene expression in vivo are largely unknown. We aimed to characterize time dependent Salmonella-induced changes of colonic mucosal gene expression in rats using whole genome microarrays. For this, rats were orally infected with Salmonella enteritidis to mimic a foodborne infection and colonic gene expression was determined at days 1, 3 and 6 post-infection (n = 8 rats per time-point). As fructo-oligosaccharides (FOS) affect colonic physiology, we analyzed colonic mucosal gene expression of FOS-fed versus cellulose-fed rats infected with Salmonella in a separate experiment. Colonic mucosal samples were isolated at day 2 post-infection. Results Salmonella affected transport (e.g. Chloride channel calcium activated 6, H+/K+ transporting Atp-ase), antimicrobial defense (e.g. Lipopolysaccharide binding protein, Defensin 5 and phospholipase A2), inflammation (e.g. calprotectin), oxidative stress related genes (e.g. Dual oxidase 2 and Glutathione peroxidase 2) and Proteolysis (e.g. Ubiquitin D and Proteosome subunit beta type 9). Furthermore, Salmonella translocation increased serum IFNγ and many interferon-related genes in colonic mucosa. The gene most strongly induced by Salmonella infection was Pancreatitis Associated Protein (Pap), showing >100-fold induction at day 6 after oral infection. Results were confirmed by Q-PCR in individual rats. Stimulation of Salmonella translocation by dietary FOS was accompanied by enhancement of the Salmonella-induced mucosal processes, not by induction of other processes. Conclusion We conclude that the colon is a target tissue for Salmonella, considering the abundant changes in mucosal gene expression

  2. Autofluorescence of normal and tumor mucosa of human colon: a comprehensive analysis

    NASA Astrophysics Data System (ADS)

    Bottiroli, Giovanni F.; Marchesini, Renato; Croce, Anna C.; Dal Fante, Marco; Cuzzoni, Carolina; Di Palma, Silvana; Spinelli, Pasquale

    1993-08-01

    Both 'in vivo' and 'ex vivo' spectrofluorometric studies of neoplastic and non-neoplastic mucosa of human colon have been carried out, in order to verify the potentials of tissue natural fluorescence as a possible parameter to distinguish normal from diseased tissues, Spectrofluorometric analysis performed at colonoscopy on patients affected by neoplasia, showed that adenocarcinoma, adenoma and non-neoplastic mucosa differ in the fluorescence emissions. The results have been interpreted according to the data obtained on cryostatic sections from biopsies by means of a microspectrofluorometric analysis carried out on each histological component.

  3. Investigation of computer-aided colonic crypt pattern analysis

    NASA Astrophysics Data System (ADS)

    Qi, Xin; Pan, Yinsheng; Sivak, Michael V., Jr.; Olowe, Kayode; Rollins, Andrew M.

    2007-02-01

    Colorectal cancer is the second leading cause of cancer-related death in the United States. Approximately 50% of these deaths could be prevented by earlier detection through screening. Magnification chromoendoscopy is a technique which utilizes tissue stains applied to the gastrointestinal mucosa and high-magnification endoscopy to better visualize and characterize lesions. Prior studies have shown that shapes of colonic crypts change with disease and show characteristic patterns. Current methods for assessing colonic crypt patterns are somewhat subjective and not standardized. Computerized algorithms could be used to standardize colonic crypt pattern assessment. We have imaged resected colonic mucosa in vitro (N = 70) using methylene blue dye and a surgical microscope to approximately simulate in vivo imaging with magnification chromoendoscopy. We have developed a method of computerized processing to analyze the crypt patterns in the images. The quantitative image analysis consists of three steps. First, the crypts within the region of interest of colonic tissue are semi-automatically segmented using watershed morphological processing. Second, crypt size and shape parameters are extracted from the segmented crypts. Third, each sample is assigned to a category according to the Kudo criteria. The computerized classification is validated by comparison with human classification using the Kudo classification criteria. The computerized colonic crypt pattern analysis algorithm will enable a study of in vivo magnification chromoendoscopy of colonic crypt pattern correlated with risk of colorectal cancer. This study will assess the feasibility of screening and surveillance of the colon using magnification chromoendoscopy.

  4. Inhibitory effects of zingerone, a pungent component of Zingiber officinale Roscoe, on colonic motility in rats.

    PubMed

    Iwami, Momoe; Shiina, Takahiko; Hirayama, Haruko; Shima, Takeshi; Takewaki, Tadashi; Shimizu, Yasutake

    2011-01-01

    Ginger (rhizome of Zingiber officinale Roscoe) is an herbal medicine for the treatment of gastrointestinal disorders including constipation and diarrhea. Zingerone is a likely active constituent responsible for the antidiarrheal activity of ginger. The current study was designed to characterize pharmacological actions of zingerone on colonic motility. To evaluate pharmacological effects of zingerone on colonic motility, we used isolated colonic segments from rats, in which mechanical responses were recorded in the longitudinal direction. In addition, we evaluated the effects on colonic motility in vivo by measuring intraluminal pressure changes and expelled fluid volume from the colon in anesthetized rats. Zingerone was applied to the lumen of the colon to allow the drug to access from the mucosal side. Zingerone inhibited spontaneous contractile movements in the isolated colonic segments in a dose-dependent manner. The inhibitory effects of zingerone on colonic movements were not affected by pretreatment with capsazepine, a typical antagonist of transient receptor potential vanilloid 1. In addition, tetrodotoxin, a blocker of voltage-dependent sodium channels on neurons, did not affect the suppression of colonic movements by zingerone, suggesting that zingerone acts on the smooth muscles directly. Zingerone also attenuated colonic motility in vivo without affecting blood pressure and heart rate. The effects were reversible and reproducible. Our findings suggest that zingerone can inhibit colonic motility via direct action on smooth muscles. Zingerone might exert beneficial therapeutic effects on hypermotility-induced diarrhea by abrogating excessive gastrointestinal motility. PMID:20799069

  5. Effect of black raspberry ( Rubus occidentalis L.) extract variation conditioned by cultivar, production site, and fruit maturity stage on colon cancer cell proliferation.

    PubMed

    Johnson, Jodee L; Bomser, Joshua A; Scheerens, Joseph C; Giusti, M Monica

    2011-03-01

    Black raspberries have been shown to inhibit multiple stages of oral, esophageal, and colon cancer. The objective of this study was to evaluate how black raspberry extract variability conditioned by horticultural factors affected the antiproliferative activity of 75 black raspberry extracts using an in vitro colon cancer cell model. HT-29 cells grown in 96-well plates were treated with freeze-dried extracts at 0.6 and 1.2 mg of extract/mL of medium. Percent cell growth inhibition for each concentration of the extracts was determined using the sulforhodamine B assay. All extracts significantly inhibited the growth of HT-29 colon cancer cells in a dose-dependent manner. Cell proliferation was significantly influenced by cultivar, production site, and stage of maturity. The lack of correlation between growth inhibition and extract total phenolic and total monomeric anthocyanin assays suggested horticultural parameters influence bioactivity in a complex manner.

  6. Parameter Stability of the Functional–Structural Plant Model GREENLAB as Affected by Variation within Populations, among Seasons and among Growth Stages

    PubMed Central

    Ma, Yuntao; Li, Baoguo; Zhan, Zhigang; Guo, Yan; Luquet, Delphine; de Reffye, Philippe; Dingkuhn, Michael

    2007-01-01

    Background and Aims It is increasingly accepted that crop models, if they are to simulate genotype-specific behaviour accurately, should simulate the morphogenetic process generating plant architecture. A functional–structural plant model, GREENLAB, was previously presented and validated for maize. The model is based on a recursive mathematical process, with parameters whose values cannot be measured directly and need to be optimized statistically. This study aims at evaluating the stability of GREENLAB parameters in response to three types of phenotype variability: (1) among individuals from a common population; (2) among populations subjected to different environments (seasons); and (3) among different development stages of the same plants. Methods Five field experiments were conducted in the course of 4 years on irrigated fields near Beijing, China. Detailed observations were conducted throughout the seasons on the dimensions and fresh biomass of all above-ground plant organs for each metamer. Growth stage-specific target files were assembled from the data for GREENLAB parameter optimization. Optimization was conducted for specific developmental stages or the entire growth cycle, for individual plants (replicates), and for different seasons. Parameter stability was evaluated by comparing their CV with that of phenotype observation for the different sources of variability. A reduced data set was developed for easier model parameterization using one season, and validated for the four other seasons. Key Results and Conclusions The analysis of parameter stability among plants sharing the same environment and among populations grown in different environments indicated that the model explains some of the inter-seasonal variability of phenotype (parameters varied less than the phenotype itself), but not inter-plant variability (parameter and phenotype variability were similar). Parameter variability among developmental stages was small, indicating that parameter

  7. Th22 cells control colon tumorigenesis through STAT3 and Polycomb Repression complex 2 signaling

    PubMed Central

    Sun, Danfeng; Lin, Yanwei; Hong, Jie; Chen, Haoyan; Nagarsheth, Nisha; Peng, Dongjun; Wei, Shuang; Huang, Emina; Fang, Jingyuan; Kryczek, Ilona; Zou, Weiping

    2016-01-01

    ABSTRACT Th22 cells traffic to and retain in the colon cancer microenvironment, and target core stem cell genes and promote colon cancer stemness via STAT3 and H3K79me2 signaling pathway and contribute to colon carcinogenesis. However, whether Th22 cells affect colon cancer cell proliferation and apoptosis remains unknown. We studied the interaction between Th22 cells and colon cancer cells in the colon cancer microenvironment. Colon cancer proliferation was examined by flow cytometry analysis and H3 thymidine incorporation. Cell cycle related genes were quantified by real-time PCR and Western blotting. We transfected colon cancer cells with lentiviral vector encoding specific gene shRNAs and used chromatin immunoprecipitation (ChIP) assay to determine the genetic signaling involved in interleukin (IL)-22-mediated colon cancer cell proliferation. We showed that Th22 cells released IL-22 and stimulated colon cancer proliferation. Mechanistically, IL-22 activated STAT3, and subsequently STAT3 bound to the promoter areas of the Polycomb Repression complex 2 (PRC2) components SUZ12 and EED, and stimulated the expression of PRC2. Consequently, the activated PRC2 catalyzed the promoters of the cell cycle check-point genes p16 and p21, and inhibited their expression through H3K27me3-mediated histone methylation, and ultimately caused colon cancer cell proliferation. Bioinformatics analysis revealed that the levels of IL-22 expression positively correlated with the levels of genes controlling cancer proliferation and cell cycling in colon cancer. In addition to controlling colon cancer stemness, Th22 cells support colon carcinogenesis via affecting colon cancer cell proliferation through a distinct histone modification. PMID:27622053

  8. Th22 cells control colon tumorigenesis through STAT3 and Polycomb Repression complex 2 signaling.

    PubMed

    Sun, Danfeng; Lin, Yanwei; Hong, Jie; Chen, Haoyan; Nagarsheth, Nisha; Peng, Dongjun; Wei, Shuang; Huang, Emina; Fang, Jingyuan; Kryczek, Ilona; Zou, Weiping

    2016-08-01

    Th22 cells traffic to and retain in the colon cancer microenvironment, and target core stem cell genes and promote colon cancer stemness via STAT3 and H3K79me2 signaling pathway and contribute to colon carcinogenesis. However, whether Th22 cells affect colon cancer cell proliferation and apoptosis remains unknown. We studied the interaction between Th22 cells and colon cancer cells in the colon cancer microenvironment. Colon cancer proliferation was examined by flow cytometry analysis and H(3) thymidine incorporation. Cell cycle related genes were quantified by real-time PCR and Western blotting. We transfected colon cancer cells with lentiviral vector encoding specific gene shRNAs and used chromatin immunoprecipitation (ChIP) assay to determine the genetic signaling involved in interleukin (IL)-22-mediated colon cancer cell proliferation. We showed that Th22 cells released IL-22 and stimulated colon cancer proliferation. Mechanistically, IL-22 activated STAT3, and subsequently STAT3 bound to the promoter areas of the Polycomb Repression complex 2 (PRC2) components SUZ12 and EED, and stimulated the expression of PRC2. Consequently, the activated PRC2 catalyzed the promoters of the cell cycle check-point genes p16 and p21, and inhibited their expression through H3K27me3-mediated histone methylation, and ultimately caused colon cancer cell proliferation. Bioinformatics analysis revealed that the levels of IL-22 expression positively correlated with the levels of genes controlling cancer proliferation and cell cycling in colon cancer. In addition to controlling colon cancer stemness, Th22 cells support colon carcinogenesis via affecting colon cancer cell proliferation through a distinct histone modification. PMID:27622053

  9. Alcoholism and the Impact of Intrafamilial Discord-Affect Parameters: A Conceptual Utilization of the Family as a Sub-System.

    ERIC Educational Resources Information Center

    Weil, Mildred W.; Jones, Jean

    Parameters of intrafamilial discord have been identified in this study by examining interaction in the family of orientation, establishing their relationship to alcoholism in the invididual. The sample was comprised of 96 problem drinkers, both public and private patients, who are receiving help from Straight and Narrow Incorporated, Paterson, New…

  10. Critical rearing parameters of Tetrastichus planipennisi (Hymenoptera: Eulophidae) as affected by host-plant substrate and host-parasitoid group structure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Laboratory studies were conducted to evaluate the potential impact of host-plant substrate types, host-parasitoid group size and host to parasitoid ratios on select fitness parameters of the larval parasitoid Tetrastichus planipennisi Yang, newly introduced for biological control of the invasive eme...

  11. Pathways to Colonization

    NASA Technical Reports Server (NTRS)

    Smitherman, David V., Jr.

    2003-01-01

    The steps required for space colonization are many to grow from our current 3-person International Space Station, now under construction, to an infrastructure that can support hundreds and eventually thousands of people in space. This paper will summarize the author's findings from numerous studies and workshops on related subjects and identify some of the critical next steps toward space colonization. Findings will be drawn from the author s previous work on space colony design, space infrastructure workshops, and various studies that addressed space policy. In conclusion, this paper will note that significant progress has been made on space facility construction through the International Space Station program, and that significant efforts are needed in the development of new reusable Earth to Orbit transportation systems. The next key steps will include reusable in space transportation systems supported by in space propellant depots, the continued development of inflatable habitat and space elevator technologies, and the resolution of policy issues that will establish a future vision for space development.

  12. [Colonic histiocytosis (author's transl)].

    PubMed

    Remmele, W; Endris, R

    1977-02-01

    Macrophages accumulating various substances can be detected in the mucosa of the small and large bowel under physiological and various pathological conditions. Among these the so-called PAS-positive macrophages have attracted much attention in recent times. Abundant occurrence of such cells in the intestinal mucosa has been termed "colonic histiocytosis". The occurrence of PAS-positive macrophages was investigated in 200 unselected and otherwise normal biopsy specimens of rectal mucosa; no correlation was found between the occurrence of these cells on the one hand and any intestinal or extraintestinal disease on the other. PAS-positive macrophages were mostly found close to the surface of the mucosa or to the cryptal epithelium as well as between the crypts. It is suggested to abandon the term "colonic histiocytosis" since it induces a false impression of a disease entity in the clinician (and may be related falsely e.g. to "histiocytosis X", and since the clinician may tend to attribute unnecessary importance to this harmless finding.

  13. Competition for space during bacterial colonization of a surface.

    PubMed

    Lloyd, Diarmuid P; Allen, Rosalind J

    2015-09-01

    Competition for space is ubiquitous in the ecology of both microorganisms and macro-organisms. We introduce a bacterial model system in which the factors influencing competition for space during colonization of an initially empty habitat can be tracked directly. Using fluorescence microscopy, we follow the fate of individual Escherichia coli bacterial cell lineages as they undergo expansion competition (the race to be the first to colonize a previously empty territory), and as they later compete at boundaries between clonal territories. Our experiments are complemented by computer simulations of a lattice-based model. We find that both expansion competition, manifested as differences in individual cell lag times, and boundary competition, manifested as effects of neighbour cell geometry, can play a role in colonization success, particularly when lineages expand exponentially. This work provides a baseline for investigating how ecological interactions affect colonization of space by bacterial populations, and highlights the potential of bacterial model systems for the testing and development of ecological theory.

  14. Anatomically correct deformable colon phantom

    NASA Astrophysics Data System (ADS)

    Norris, James A.; Barton, Michael D.; Davis, Brynmor J.; Bieszczad, Jerry; Meunier, Norm L.; Brown, Nathan W.; Kynor, David B.

    2011-03-01

    We describe a technique to build a soft-walled colon phantom that provides realistic lumen anatomy in computed tomography (CT) images. The technique begins with the geometry of a human colon measured during CT colonography (CTC). The three-dimensional air-filled colonic lumen is segmented and then replicated using stereolithography (SLA). The rigid SLA model includes large-scale features (e.g., haustral folds and tenia coli bands) down to small-scale features (e.g., a small pedunculated polyp). Since the rigid model represents the internal air-filled volume, a highly-pliable silicone polymer is painted onto the rigid model. This thin layer of silicone, when removed, becomes the colon wall. Small 3 mm diameter glass beads are affixed to the outer wall. These glass beads show up with high intensity in CT scans and provide a ground truth for evaluating performance of algorithms designed to register prone and supine CTC data sets. After curing, the silicone colon wall is peeled off the rigid model. The resulting colon phantom is filled with air and submerged in a water bath. CT images and intraluminal fly-through reconstructions from CTC scans of the colon phantom are compared against patient data to demonstrate the ability of the phantom to simulate a human colon.

  15. Bacterial Traits Involved in Colonization of Arabidopsis thaliana Roots by Bacillus amyloliquefaciens FZB42.

    PubMed

    Dietel, Kristin; Beator, Barbara; Budiharjo, Anto; Fan, Ben; Borriss, Rainer

    2013-03-01

    Colonization studies previously performed with a green-fluorescent-protein, GFP, labeled derivative of Bacillus amyloliquefaciens FZB42 revealed that the bacterium behaved different in colonizing surfaces of plant roots of different species (Fan et al., 2012). In order to extend these studies and to elucidate which genes are crucial for root colonization, we applied targeted mutant strains to Arabidopsis seedlings. The fates of root colonization in mutant strains impaired in synthesis of alternative sigma factors, non-ribosomal synthesis of lipopeptides and polyketides, biofilm formation, swarming motility, and plant growth promoting activity were analyzed by confocal laser scanning microscopy. Whilst the wild-type strain heavily colonized surfaces of root tips and lateral roots, the mutant strains were impaired in their ability to colonize root tips and most of them were unable to colonize lateral roots. Ability to colonize plant roots is not only dependent on the ability to form biofilms or swarming motility. Six mutants, deficient in abrB-, sigH-, sigD-, nrfA-, yusV and RBAM017410, but not affected in biofilm formation, displayed significantly reduced root colonization. The nrfA- and yusV-mutant strains colonized border cells and, partly, root surfaces but did not colonize root tips or lateral roots.

  16. Bacterial Traits Involved in Colonization of Arabidopsis thaliana Roots by Bacillus amyloliquefaciens FZB42

    PubMed Central

    Dietel, Kristin; Beator, Barbara; Budiharjo, Anto; Fan, Ben; Borriss, Rainer

    2013-01-01

    Colonization studies previously performed with a green-fluorescent-protein, GFP, labeled derivative of Bacillus amyloliquefaciens FZB42 revealed that the bacterium behaved different in colonizing surfaces of plant roots of different species (Fan et al., 2012). In order to extend these studies and to elucidate which genes are crucial for root colonization, we applied targeted mutant strains to Arabidopsis seedlings. The fates of root colonization in mutant strains impaired in synthesis of alternative sigma factors, non-ribosomal synthesis of lipopeptides and polyketides, biofilm formation, swarming motility, and plant growth promoting activity were analyzed by confocal laser scanning microscopy. Whilst the wild-type strain heavily colonized surfaces of root tips and lateral roots, the mutant strains were impaired in their ability to colonize root tips and most of them were unable to colonize lateral roots. Ability to colonize plant roots is not only dependent on the ability to form biofilms or swarming motility. Six mutants, deficient in abrB-, sigH-, sigD-, nrfA-, yusV and RBAM017410, but not affected in biofilm formation, displayed significantly reduced root colonization. The nrfA- and yusV-mutant strains colonized border cells and, partly, root surfaces but did not colonize root tips or lateral roots. PMID:25288929

  17. Approaches that ascertain the role of dietary compounds in colonic cancer cells

    PubMed Central

    Bordonaro, Michael; Venema, Koen; Putri, Adeline K; Lazarova, Darina

    2014-01-01

    Preventive approaches against cancer have not been fully developed and applied. For example, the incidence of some types of cancer, including colon cancer, is highly dependent upon lifestyle, and therefore, amenable to prevention. Among the lifestyle factors, diet strongly affects the incidence of colon cancer; however, there are no definitive dietary recommendations that protect against this malignancy. The association between diet-derived bioactives and development of colonic neoplasms will remain ill defined if we do not take into account: (1) the identity of the metabolites present in the colonic lumen; (2) their concentrations in the colon; and (3) the effect of the colonic contents on the function of individual bioactives. We review two approaches that address these questions: the use of fecal water and in vitro models of the human colon. Compared to treatment with individual diet-derived compounds, the exposure of colon cancer cells to samples from fecal water or human colon simulators mimics closer the in vitro conditions and allows for more reliable studies on the effects of diet on colon cancer development. The rationale and the advantages of these strategies are discussed from the perspective of a specific question on how to analyze the combined effect of two types of bioactives, butyrate and polyphenol metabolites, on colon cancer cells. PMID:24578783

  18. Gnotobiotic Human Colon Ex Vivo

    PubMed Central

    McDermott, Frank D.; Folan, David M. A.; Winter, Des C.; Folan, Michael A.; Baird, Alan W.

    2015-01-01

    Background A novel emulsion with efficacy as an agent for eliminating biofilms was selected. The aim of this study was to examine efficacy and effect of a formulation of ML:8 against commensal bacteria harvested from ex vivo human colonic tissues. Methods Mucosal sheets, obtained at the time of surgery, were exposed for 2 minutes to one of four solutions: Krebs-Hensleit (KH) solution, saline (NaCl; 0.9%), povidone iodine (1%), or ML:8 (2%); n = 4. Lumenal surfaces were swabbed for culture under aerobic or anaerobic conditions. Following treatment, each sheet was mounted in Ussing chambers and voltage clamped. Tissues were challenged with carbachol. Permeability coefficient (Papp) was determined using mannitol fluxes. At the end of each experiment, tissues were examined histologically. Results Similar colony forming units grew in aerobic and anaerobic conditions in both control and NaCl treated tissues. Iodine reduced and ML:8 virtually abolished viable bacteria. Basal electrophysiological parameters were not different between treatments. Transepithelial electrical resistance values did not differ between groups. All tissues responded to carbachol, although this was attenuated in iodine treated tissue. Papp values were slightly elevated in all treated tissues but this did not reach significance. Histopathological assessment revealed no overt damage to tissues. Conclusion Brief exposure to ML:8 reduced culturable bacterial burden from human intestinal tissues harvested at the time of surgical resection. Such gnotobiotic tissues retain structural and functional integrity. This is a novel approach to reduce bacterial burden. PMID:27785304

  19. Critical desertification transition in semi-arid ecosystems: The role of local facilitation and colonization rate

    NASA Astrophysics Data System (ADS)

    Corrado, Raffaele; Cherubini, Anna Maria; Pennetta, Cecilia

    2015-05-01

    In this work we study the effect of two different ecological mechanisms on the desertification transition in arid or semi-arid ecosystems, modeled by a stochastic cellular automaton. Namely we consider the role of the facilitation mechanism, i.e. the local positive effects of plants on their neighborhood and of colonization factors, such as seed production, survival and germination probabilities. Within the model, the strength of these two mechanisms is determined by the parameters f and b, respectively controlling the rates of the recovery and colonization processes. In particular we focus on the full desertification transition occurring at increasing value of the mortality rate m and we discuss how the values of f and b affect the critical mortality mc , the critical exponents β and γσ‧, determining the power-law scaling of the average vegetation density and of the root-mean-square deviation of the density fluctuations, and the character of the transition: continuous or abrupt. We show that mc strongly depends on both f and b, a dependence which accounts for the higher resilience of the ecosystems to external stresses as a consequence of an increased effectiveness of positive feedback effects. On the other hand, concerning the value of the exponents and the character of the transition, our results point out that both these features are unaffected by changes in the strength of the local facilitation. Viceversa, we show that an increase of the colonization factor b significantly modifies the values of the exponents and the order of the transition, changing a continuous transition into an abrupt one. We explain these results in terms of the different range of the interactions characterizing facilitation and colonization mechanisms.

  20. Colon interposition for oesophageal replacement.

    PubMed

    Thomas, Pascal A; Gilardoni, Adrian; Trousse, Delphine; D'Journo, Xavier B; Avaro, Jean-Philippe; Doddoli, Christophe; Giudicelli, Roger; Fuentes, Pierre

    2009-01-01

    The choice of the colon as an oesophageal substitute results primarily from the unavailability of the stomach. However, given its durability and function, colon interposition keeps elective indications in patients with benign or malignant oesophageal disease who are potential candidates for long survival. The choice of the colonic portion used for oesophageal reconstruction depends on the required length of the graft, and the encountered colonic vascular anatomy, the last being characterised by the near-invariability of the left colonic vessels, in contrast to the vascular pattern of the right side of the colon. Accordingly, the transverse colon with all or part of the ascending colon is the substitute of choice, positioned in the isoperistaltic direction, and supplied either from the left colic vessels for long grafts or middle colic vessels for shorter grafts. Technical key points are: full mobilisation of the entire colon, identification of the main colonic vessels and collaterals, and a prolonged clamping test to ensure the permeability of the chosen nourishing pedicle. Transposition through the posterior mediastinum in the oesophageal bed is the shortest one and thereby offers the best functional results. When the oesophageal bed is not available, the retrosternal route is the preferred alternative option. The food bolus travelling mainly by gravity makes straightness of the conduit of paramount importance. The proximal anastomosis is a single-layer hand-fashioned end-to-end anastomosis to prevent narrowing. When the stomach is available, the distal anastomosis is best performed at the posterior part of the antrum for the reasons of pedicle positioning and reflux prevention, and a gastric drainage procedure is added when the oesophagus and vagus nerves have been removed. In the other cases, a Roux-en-Y jejunal loop is preferable to prevent bile reflux into the colon. Additional procedures include re-establishment of the colonic continuity, a careful closure of

  1. Detection of colon cancer by terahertz techniques

    NASA Astrophysics Data System (ADS)

    Wahaia, Faustino; Valusis, Gintaras; Bernardo, Luis M.; Almeida, Abílio; Moreira, Joaquim A.; Lopes, Patricia C.; Macutkevic, Jan; Kasalynas, Irmantas; Seliuta, Dalius; Adomavicius, Ramunas; Henrique, Rui; Lopes, Machado

    2011-12-01

    Human normal and cancer affected samples of colon tissue have been measured using transmission time-domain terahertz spectroscopy and continuous wave terahertz imaging. We show that it is possible to distinguish between normal and cancerous regions in the samples when they are fixed in formalin or embedded in paraffin. The still noticeable contrast in the dried paraffin-embedded tissues could indicate that there are additional contrast-contributing factors other than water, which is the main goal of the present work. Plots of the refractive index of normal and cancer affected tissues as well as 2-D transmission THz images are shown. Experimental results are presented and the conditions for discrimination between normal and affected formalin-fixed and paraffin-embedded tissue are discussed.

  2. Hypokalemia Associated with Colonic Pseudo-Obstruction (Ogilvie's Syndrome).

    PubMed

    Sunnoqrot, Naseem; Reilly, Robert F

    2015-01-01

    We report a case of hypokalemia resulting from colonic pseudo-obstruction or Ogilvie's syndrome. Colonic pseudo-obstruction is characterized by profuse watery diarrhea that has a low sodium and high potassium concentration. It is seen in a variety of medical and surgical conditions, but its exact cause remains unknown. It is thought to result from an imbalance of sympathetic and parasympathetic input in the distal colon. The diarrhea is secretory and driven by potassium secretion rather than the inhibition of sodium reabsorption or chloride secretion, which are the most common pathophysiologic mechanisms of secretory diarrhea. Affected patients often lose >100 mmol of potassium daily. Colonic pseudo-obstruction is associated with a dramatic upregulation of the maxiK or BK potassium channel. This channel plays a prominent role in flow-mediated potassium secretion in the connecting tubule and collecting duct and is also upregulated in the distal colon in patients with advanced chronic kidney disease and end-stage renal disease. In vitro studies show that the channel is regulated by catecholamine binding to the β receptor and cyclic AMP upregulation, somatostatin and aldosterone, insights that can be used to help guide pharmacologic therapy. Nephrologists should be aware of colonic pseudo-obstruction as a cause of extrarenal potassium loss.

  3. Effect of trimebutine on colonic myoelectrical activity in IBS patients.

    PubMed

    Frexinos, J; Fioramonti, J; Bueno, L

    1985-01-01

    The effect of trimebutine 100 mg i.v. and placebo on colonic myoelectrical activity was investigated in 10 patients with the irritable bowel syndrome (IBS) (5 constipated and 5 diarrhoeic), using an intraluminal probe supporting 8 groups of electrodes. At each site examined from transverse to sigmoid colon, the electromyograms exhibited two kinds of spike bursts: short spike bursts (SSB) localized at one electrode site and appearing rhythmically at 10.3/min, and long spike bursts (LSB), isolated or propagated orally or aborally. Computerized analysis of the duration of each kind of spike burst showed that, as compared to the control, trimebutine 100 mg, selectively inhibited by 43 to 73% the mean duration of LSB activity in the transverse, descending and sigmoid colon, from 0 to 30 min after administration. The inhibitory effect was similar in constipated and diarrhoeic patients. Placebo injection did not significantly affect (p greater than 0.05) the duration of LSB and SSB activity. Variance analysis indicated that the inhibitory effect of trimebutine was significantly greater (p less than 0.05) on LSB activity in the transverse than the descending colon, and that it was absent from the sigmoid colon. The results suggest that trimebutine selectively inhibits the propulsive activity of the proximal two thirds of the colon in IBS patients, and that this effect cannot entirely explain its therapeutic efficacy in IBS. PMID:3987797

  4. Tamoxifen affects glucose and lipid metabolism parameters, causes browning of subcutaneous adipose tissue and transient body composition changes in C57BL/6NTac mice.

    PubMed

    Hesselbarth, Nico; Pettinelli, Chiara; Gericke, Martin; Berger, Claudia; Kunath, Anne; Stumvoll, Michael; Blüher, Matthias; Klöting, Nora

    2015-08-28

    Tamoxifen is a selective estrogen receptor (ER) modulator which is widely used to generate inducible conditional transgenic mouse models. Activation of ER signaling plays an important role in the regulation of adipose tissue (AT) metabolism. We therefore tested the hypothesis that tamoxifen administration causes changes in AT biology in vivo. 12 weeks old male C57BL/6NTac mice were treated with either tamoxifen (n = 18) or vehicle (n = 18) for 5 consecutive days. Tamoxifen treatment effects on body composition, energy homeostasis, parameters of AT biology, glucose and lipid metabolism were investigated up to an age of 18 weeks. We found that tamoxifen treatment causes: I) significantly increased HbA1c, triglyceride and free fatty acid serum concentrations (p < 0.01), II) browning of subcutaneous AT and increased UCP-1 expression, III) increased AT proliferation marker Ki67 mRNA expression, IV) changes in adipocyte size distribution, and V) transient body composition changes. Tamoxifen may induce changes in body composition, whole body glucose and lipid metabolism and has significant effects on AT biology, which need to be considered when using Tamoxifen as a tool to induce conditional transgenic mouse models. Our data further suggest that tamoxifen-treated wildtype mice should be characterized in parallel to experimental transgenic models to control for tamoxifen administration effects.

  5. Tamoxifen affects glucose and lipid metabolism parameters, causes browning of subcutaneous adipose tissue and transient body composition changes in C57BL/6NTac mice

    SciTech Connect

    Hesselbarth, Nico; Pettinelli, Chiara; Gericke, Martin; Berger, Claudia; Kunath, Anne; Stumvoll, Michael; Blüher, Matthias; Klöting, Nora

    2015-08-28

    Tamoxifen is a selective estrogen receptor (ER) modulator which is widely used to generate inducible conditional transgenic mouse models. Activation of ER signaling plays an important role in the regulation of adipose tissue (AT) metabolism. We therefore tested the hypothesis that tamoxifen administration causes changes in AT biology in vivo. 12 weeks old male C57BL/6NTac mice were treated with either tamoxifen (n = 18) or vehicle (n = 18) for 5 consecutive days. Tamoxifen treatment effects on body composition, energy homeostasis, parameters of AT biology, glucose and lipid metabolism were investigated up to an age of 18 weeks. We found that tamoxifen treatment causes: I) significantly increased HbA{sub 1c}, triglyceride and free fatty acid serum concentrations (p < 0.01), II) browning of subcutaneous AT and increased UCP-1 expression, III) increased AT proliferation marker Ki67 mRNA expression, IV) changes in adipocyte size distribution, and V) transient body composition changes. Tamoxifen may induce changes in body composition, whole body glucose and lipid metabolism and has significant effects on AT biology, which need to be considered when using Tamoxifen as a tool to induce conditional transgenic mouse models. Our data further suggest that tamoxifen-treated wildtype mice should be characterized in parallel to experimental transgenic models to control for tamoxifen administration effects. - Highlights: • Tamoxifen treatment causes significantly increased HbA{sub 1c}, triglyceride and free fatty acid serum concentrations. • Tamoxifen induces browning of subcutaneous AT and increased UCP-1 expression. • Tamoxifen changes adipocyte size distribution, and transient body composition.

  6. Two-spotted spider mite reared on resistant eggplant affects consumption rate and life table parameters of its predator, Typhlodromus bagdasarjani (Acari: Phytoseiidae).

    PubMed

    Khanamani, Mostafa; Fathipour, Yaghoub; Hajiqanbar, Hamidreza; Sedaratian, Amin

    2014-06-01

    The study of interactions between host plant cultivars and biological control agents is important in integrated pest management programs. In this study, the life table parameters and predation rate of Typhlodromus bagdasarjani Wainstein & Arutunjan were determined on two-spotted spider mites reared on a susceptible (Isfahan) or a resistant (Neishabour) eggplant cultivar. All experiments were carried out under laboratory conditions, at 25 ± 1 °C, 60 ± 5 % RH and a photoperiod of 16:8 (L:D) h. A significant difference was observed between mean developmental time of immature stages of T. bagdasarjani on the two eggplant cultivars: 6.6 versus 7.5 days, on the susceptible and resistant cultivar, respectively. Net reproductive rate (R 0) of T. bagdasarjani did not differ between the cultivars. Doubling time on the susceptible and resistant cultivars was 3.48 versus 5.72 days, mean generation time (T) was 10.13 versus 16.08 days, respectively. Total fecundity was higher on susceptible than on resistant eggplants, the intrinsic rate of population increase (r) was 0.188 versus 0.119 day(-1), respectively. Daily and total prey consumption of various life stages of T. bagdasarjani on two-spotted spider mite reared on susceptible versus resistant eggplant differed; total consumption was higher on spider mites reared on the resistant cultivar. However, the lower intrinsic rate of increase and higher mortality of the predator on the resistant eggplant (Neishabour) revealed that more attention should be devoted to integrated control of spider mites using resistant cultivars and phytoseiid mites.

  7. Blood parameters and corneal-reflex of finishing pigs with and without lung affections observed post mortem in two abattoirs stunning with CO₂.

    PubMed

    Fries, R; Rindermann, G; Siegling-Vlitakis, C; Bandick, N; Bräutigam, L; Buschulte, A; Irsigler, H; Wolf, K; Hartmann, H

    2013-02-01

    In two pig abattoirs of different slaughter capacities, the stunning efficacy of CO2 on finishing pigs with and without pneumonic lesions (observed post mortem) was reflected against the corneal-reflex and blood parameters (blood pH, pCO2 and pO2) from individual finishers. Stunning duration was 120 s (abattoir A) and 90 s (abattoir B), respectively. Pneumonia in finisher pigs is frequently observed during post mortem inspection, which may raise concerns about a delay of unconsciousness because of hampered gas exchange in the lungs. The aim of this study was to examine possible pneumonia consequences for stunning efficacy under commercial conditions. For that, corneal reflex, O2 and CO2 partial pressure in the blood as well as blood pH were measured in 2650 finishers from abattoir A and 2100 from abattoir B. The partial pressure of O2 after stunning accounted to about 3 kPa, the partial pressure of CO2 was found at levels of about 24 kPa in abattoir A (after 120 s CO2 exposure) and 17.5 kPa in abattoir B (after 90 s CO2 exposure). In abattoir A, the blood pH was at 6.9, and at 7.0 in abattoir B. The corneal reflex was observed in 6.2% of pigs in abattoir A and 17.1% of pigs in abattoir B. A correlation between pneumonic lesions and blood status was not observed. However, for some individual farms, a significant correlation between pneumonia and corneal reflex was observed. PMID:22898535

  8. Parameters affecting the stability of the digestate from a two-stage anaerobic process treating the organic fraction of municipal solid waste

    SciTech Connect

    Trzcinski, Antoine P.; Stuckey, David C.

    2011-07-15

    This paper focused on the factors affecting the respiration rate of the digestate taken from a continuous anaerobic two-stage process treating the organic fraction of municipal solid waste (OFMSW). The process involved a hydrolytic reactor (HR) that produced a leachate fed to a submerged anaerobic membrane bioreactor (SAMBR). It was found that a volatile solids (VS) removal in the range 40-75% and an operating temperature in the HR between 21 and 35 {sup o}C resulted in digestates with similar respiration rates, with all digestates requiring 17 days of aeration before satisfying the British Standard Institution stability threshold of 16 mg CO{sub 2} g VS{sup -1} day{sup -1}. Sanitization of the digestate at 65 {sup o}C for 7 days allowed a mature digestate to be obtained. At 4 g VS L{sup -1} d{sup -1} and Solid Retention Times (SRT) greater than 70 days, all the digestates emitted CO{sub 2} at a rate lower than 25 mg CO{sub 2} g VS{sup -1} d{sup -1} after 3 days of aeration, while at SRT lower than 20 days all the digestates displayed a respiration rate greater than 25 mg CO{sub 2} g VS{sup -1} d{sup -1}. The compliance criteria for Class I digestate set by the European Commission (EC) and British Standard Institution (BSI) could not be met because of nickel and chromium contamination, which was probably due to attrition of the stainless steel stirrer in the HR.

  9. Streptococcus pneumoniae Colonization Disrupts the Microbial Community within the Upper Respiratory Tract of Aging Mice

    PubMed Central

    Thevaranjan, Netusha; Whelan, Fiona J.; Puchta, Alicja; Ashu, Eta; Rossi, Laura; Surette, Michael G.

    2016-01-01

    Nasopharyngeal colonization by the Gram-positive bacterium Streptococcus pneumoniae is a prerequisite for pneumonia and invasive pneumococcal diseases. Colonization is asymptomatic, involving dynamic and complex interplay between commensals, the host immune system, and environmental factors. The elderly are at an increased risk of developing pneumonia, which might be due to changes in the respiratory microbiota that would impact bacterial colonization and persistence within this niche. We hypothesized that the composition of the upper respiratory tract (URT) microbiota changes with age and subsequently can contribute to sustained colonization and inefficient clearance of S. pneumoniae. To test this, we used a mouse model of pneumococcal colonization to compare the composition of the URT microbiota in young, middle-aged, and old mice in the naive state and during the course of colonization using nasal pharyngeal washes. Sequencing of variable region 3 (V3) of the 16S rRNA gene was used to identify changes occurring with age and throughout the course of S. pneumoniae colonization. We discovered that age affects the composition of the URT microbiota and that colonization with S. pneumoniae is more disruptive of preexisting communities in older mice. We have further shown that host-pathogen interactions following S. pneumoniae colonization can impact the populations of resident microbes, including Staphylococcus and Haemophilus. Together, our findings indicate alterations to the URT microbiota could be detrimental to the elderly, resulting in increased colonization of S. pneumoniae and decreased efficiency in its clearance. PMID:26787714

  10. Epigenetic maturation in colonic mucosa continues beyond infancy in mice.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Monozygotic twin and other epidemiologic studies indicate that epigenetic processes may play an important role in the pathogenesis of inflammatory bowel diseases that commonly affect the colonic mucosa. The peak onset of these disorders in young adulthood, suggests that epigenetic changes normally o...

  11. [Lactobacilli and colon carcinoma--A review].

    PubMed

    Wang, Shumei; Zhang, Lanwei; Shan, Yujuan

    2015-06-01

    Epidemiological studies showed that incidence of colon carcinoma is increased in the world. There are many difficulties to inhibit colon carcinoma because the causes of inducing colon carcinoma were various and interactive each other. Previous evidence supported the balance of the colonic microflora was critical in inhibiting colon carcinoma and the protection by colonic microflora could be improved by ingesting lactobacilli. Therefore, the biological functions and anticancer effects of lactobacilli attract attention of researchers. In this review we discussed the causes of colon carcinoma; the anticancer mechanisms of lactobacilli on the basis of our own studies. Eventually, we summarized the effects of anticancer of different components and metabolic products extracted from lactobacilli.

  12. Correlation of morphological and molecular parameters for colon cancer

    NASA Astrophysics Data System (ADS)

    Yuan, Shuai; Roney, Celeste A.; Li, Qian; Jiang, James; Cable, Alex; Summers, Ronald M.; Chen, Yu

    2010-02-01

    Colorectal cancer (CRC) is the second leading cause of cancer death in the United States. There is great interest in studying the relationship among microstructures and molecular processes of colorectal cancer during its progression at early stages. In this study, we use our multi-modality optical system that could obtain co-registered optical coherence tomography (OCT) and fluorescence molecular imaging (FMI) images simultaneously to study CRC. The overexpressed carbohydrate α-L-fucose on the surfaces of polyps facilitates the bond of adenomatous polyps with UEA-1 and is used as biomarker. Tissue scattering coefficient derived from OCT axial scan is used as quantitative value of structural information. Both structural images from OCT and molecular images show spatial heterogeneity of tumors. Correlations between those values are analyzed and demonstrate that scattering coefficients are positively correlated with FMI signals in conjugated. In UEA-1 conjugated samples (8 polyps and 8 control regions), the correlation coefficient is ranged from 0.45 to 0.99. These findings indicate that the microstructure of polyps is changed gradually during cancer progression and the change is well correlated with certain molecular process. Our study demonstrated that multi-parametric imaging is able to simultaneously detect morphology and molecular information and it can enable spatially and temporally correlated studies of structure-function relationships during tumor progression.

  13. Early colonizing Escherichia coli elicits remodeling of rat colonic epithelium shifting toward a new homeostatic state

    PubMed Central

    Tomas, Julie; Reygner, Julie; Mayeur, Camille; Ducroc, Robert; Bouet, Stephan; Bridonneau, Chantal; Cavin, Jean-Baptiste; Thomas, Muriel; Langella, Philippe; Cherbuy, Claire

    2015-01-01

    We investigated the effects of early colonizing bacteria on the colonic epithelium. We isolated dominant bacteria, Escherichia coli, Enterococcus faecalis, Lactobacillus intestinalis, Clostridium innocuum and a novel Fusobacterium spp., from the intestinal contents of conventional suckling rats and transferred them in different combinations into germfree (GF) adult rats. Animals were investigated after various times up to 21 days. Proliferative cell markers (Ki67, proliferating cell nuclear antigen, phospho-histone H3, cyclin A) were higher in rats monocolonized with E. coli than in GF at all time points, but not in rats monocolonized with E. faecalis. The mucin content of goblet cells declined shortly after E. coli administration whereas the mucus layer doubled in thickness. Fluorescence in situ hybridization analyses revealed that E. coli resides in this mucus layer. The epithelial mucin content progressively returned to baseline, following an increase in KLF4 and in the cell cycle arrest-related proteins p21CIP1 and p27KIP1. Markers of colonic differentiated cells involved in electrolyte (carbonic anhydrase II and slc26A3) and water (aquaglyceroporin3 (aqp3)) transport, and secretory responses to carbachol were modulated after E. coli inoculation suggesting that ion transport dynamics were also affected. The colonic responses to simplified microbiotas differed substantially according to whether or not E. coli was combined with the other four bacteria. Thus, proliferation markers increased substantially when E. coli was in the mix, but very much less when it was absent. This work demonstrates that a pioneer strain of E. coli elicits sequential epithelial remodeling affecting the structure, mucus layer and ionic movements and suggests this can result in a microbiota-compliant state. PMID:25012905

  14. Integrated datasets characterize metabolic interactions between mouse’s colonic mucosa, colonic-cecal contents and feces

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The pattern of metabolites produced by the gut microbiome comprises a phenotype indicative of the means by which that microbiome affects the gut. We characterized that phenotype by conducting metabolomic analyses of the colonic-cecal contents, comparing that to the metabolite patterns of feces and c...

  15. Cancers of the colon and rectum: identical or fraternal twins?

    PubMed

    Hong, Theodore S; Clark, Jeffrey W; Haigis, Kevin M

    2012-02-01

    Colorectal cancer represents a major cause of cancer morbidity and mortality, with approximately 1.2 million cases and 600,000 deaths worldwide each year. Because of the anatomic continuity of the colon into the rectum, cancers affecting these organs have historically been considered equivalent. In this Prospective, we discuss the clinical and experimental data suggesting that colon cancer and rectal cancer are highly related, but distinct, diseases. Reconsidering the relationship between these cancers has implications for the development of new therapeutic paradigms. PMID:22585856

  16. The Use of Flagella and Motility for Plant Colonization and Fitness by Different Strains of the Foodborne Pathogen Listeria monocytogenes

    PubMed Central

    Gorski, Lisa; Duhé, Jessica M.; Flaherty, Denise

    2009-01-01

    The role of flagella and motility in the attachment of the foodborne pathogen Listeria monocytogenes to various surfaces is mixed with some systems requiring flagella for an interaction and others needing only motility for cells to get to the surface. In nature this bacterium is a saprophyte and contaminated produce is an avenue for infection. Previous studies have documented the ability of this organism to attach to and colonize plant tissue. Motility mutants were generated in three wild type strains of L. monocytogenes by deleting either flaA, the gene encoding flagellin, or motAB, genes encoding part of the flagellar motor, and tested for both the ability to colonize sprouts and for the fitness of that colonization. The motAB mutants were not affected in the colonization of alfalfa, radish, and broccoli sprouts; however, some of the flaA mutants showed reduced colonization ability. The best colonizing wild type strain was reduced in colonization on all three sprout types as a result of a flaA deletion. A mutant in another background was only affected on alfalfa. The third, a poor alfalfa colonizer was not affected in colonization ability by any of the deletions. Fitness of colonization was measured in experiments of competition between mixtures of mutant and parent strains on sprouts. Here the flaA and motAB mutants of the three strain backgrounds were impaired in fitness of colonization of alfalfa and radish sprouts, and one strain background showed reduced fitness of both mutant types on broccoli sprouts. Together these data indicate a role for flagella for some strains to physically colonize some plants, while the fitness of that colonization is positively affected by motility in almost all cases. PMID:19357783

  17. The use of flagella and motility for plant colonization and fitness by different strains of the foodborne pathogen Listeria monocytogenes.

    PubMed

    Gorski, Lisa; Duhé, Jessica M; Flaherty, Denise

    2009-01-01

    The role of flagella and motility in the attachment of the foodborne pathogen Listeria monocytogenes to various surfaces is mixed with some systems requiring flagella for an interaction and others needing only motility for cells to get to the surface. In nature this bacterium is a saprophyte and contaminated produce is an avenue for infection. Previous studies have documented the ability of this organism to attach to and colonize plant tissue. Motility mutants were generated in three wild type strains of L. monocytogenes by deleting either flaA, the gene encoding flagellin, or motAB, genes encoding part of the flagellar motor, and tested for both the ability to colonize sprouts and for the fitness of that colonization. The motAB mutants were not affected in the colonization of alfalfa, radish, and broccoli sprouts; however, some of the flaA mutants showed reduced colonization ability. The best colonizing wild type strain was reduced in colonization on all three sprout types as a result of a flaA deletion. A mutant in another background was only affected on alfalfa. The third, a poor alfalfa colonizer was not affected in colonization ability by any of the deletions. Fitness of colonization was measured in experiments of competition between mixtures of mutant and parent strains on sprouts. Here the flaA and motAB mutants of the three strain backgrounds were impaired in fitness of colonization of alfalfa and radish sprouts, and one strain background showed reduced fitness of both mutant types on broccoli sprouts. Together these data indicate a role for flagella for some strains to physically colonize some plants, while the fitness of that colonization is positively affected by motility in almost all cases.

  18. Microprocessor-controlled colonic peristalsis: dynamic parametric modeling in dogs.

    PubMed

    Rashev, Peter Z; Amaris, Manuel; Bowes, Kenneth L; Mintchev, Martin P

    2002-05-01

    The study aimed at completing a model of functional colonic electric stimulation and testing it for artificial recreation of peristalsis in dogs. Dynamic measurements of invoked single contractions obtained from two unconscious dogs as well as previously reported static contraction properties were utilized to suggest the optimal stimulation parameters of: (1) length of the stimulating electrodes, (2) separation between the successive electrode sets, (3) duration, and (4) phase lag between the stimuli sequentially applied to the electrode sets. The derived electrode configuration and stimulation pattern were adjusted for different anatomical dimensions and tested in distended colon full of viscous content. Forward and backward propagating peristaltic waves were invoked in two other unconscious dogs, indicating that the recreation of colonic peristalsis under microprocessor control is feasible.

  19. Estimation of AM fungal colonization - Comparability and reliability of classical methods.

    PubMed

    Füzy, Anna; Biró, Ibolya; Kovács, Ramóna; Takács, Tünde

    2015-12-01

    The characterization of mycorrhizal status in hosts can be a good indicator of symbiotic associations in inoculation experiments or in ecological research. The most common microscopic-based observation methods, such as (i) the gridline intersect method, (ii) the magnified intersections method and (iii) the five-class system of Trouvelot were tested to find the most simple, easily executable, effective and objective ones and their appropriate parameters for characterization of mycorrhizal status. In a pot experiment, white clover (Trifolium repens L.) host plant was inoculated with 6 (BEG144; syn. Rhizophagus intradices) in pumice substrate to monitor the AMF colonization properties during host growth. Eleven (seven classical and four new) colonization parameters were estimated by three researchers in twelve sampling times during plant growth. Variations among methods, observers, parallels, or individual plants were determined and analysed to select the most appropriate parameters and sampling times for monitoring. The comparability of the parameters of the three methods was also tested. As a result of the experiment classical parameters were selected for hyphal colonization: colonization frequency in the first stage or colonization density in the later period, and arbuscular richness of roots. A new parameter was recommended to determine vesicule and spore content of colonized roots at later stages of symbiosis.

  20. Estimation of AM fungal colonization - Comparability and reliability of classical methods.

    PubMed

    Füzy, Anna; Biró, Ibolya; Kovács, Ramóna; Takács, Tünde

    2015-12-01

    The characterization of mycorrhizal status in hosts can be a good indicator of symbiotic associations in inoculation experiments or in ecological research. The most common microscopic-based observation methods, such as (i) the gridline intersect method, (ii) the magnified intersections method and (iii) the five-class system of Trouvelot were tested to find the most simple, easily executable, effective and objective ones and their appropriate parameters for characterization of mycorrhizal status. In a pot experiment, white clover (Trifolium repens L.) host plant was inoculated with 6 (BEG144; syn. Rhizophagus intradices) in pumice substrate to monitor the AMF colonization properties during host growth. Eleven (seven classical and four new) colonization parameters were estimated by three researchers in twelve sampling times during plant growth. Variations among methods, observers, parallels, or individual plants were determined and analysed to select the most appropriate parameters and sampling times for monitoring. The comparability of the parameters of the three methods was also tested. As a result of the experiment classical parameters were selected for hyphal colonization: colonization frequency in the first stage or colonization density in the later period, and arbuscular richness of roots. A new parameter was recommended to determine vesicule and spore content of colonized roots at later stages of symbiosis. PMID:26689879

  1. Taste sensing in the colon.

    PubMed

    Kaji, Izumi; Karaki, Shin-ichiro; Kuwahara, Atsukazu

    2014-01-01

    The colonic lumen is continually exposed to many compounds, including beneficial and harmful compounds that are produced by colonic microflora. The intestinal epithelia form a barrier between the internal and luminal (external) environments. Chemical receptors that sense the luminal environment are thought to play important roles as sensors and as modulators of epithelial cell functions. The recent molecular identification of various membrane receptor proteins has revealed the sensory role of intestinal epithelial cells. Nutrient sensing by these receptors in the small intestine is implicated in nutrient absorption and metabolism. However, little is known about the physiological roles of chemosensors in the large intestine. Since 1980s, researchers have examined the effects of short-chain fatty acids (SCFA), the primary products of commensal bacteria, on gut motility, secretion, and incretin release, for example. In this decade, the SCFA receptor genes and their expression were identified in the mammalian colon. Furthermore, many other chemical receptors, including taste and olfactory receptors have been found in colonic epithelial cells. These findings indicate that the large intestinal epithelia express chemosensors that detect the luminal contents, particularly bacterial metabolites, and induce the host defense systems and the modulation of systemic metabolism via incretin release. In this review, we describe the local effects of chemical stimuli on the lumen associated with the expression pattern of sensory receptors. We propose that sensory receptors expressed in the colonic mucosa play important roles in luminal chemosensing to maintain homeostasis.

  2. Serrated polyps of the colon.

    PubMed

    Sugumar, Aravind; Sinicrope, Frank A

    2010-12-17

    Until recently, colonic polyps were traditionally classified as either hyperplastic or adenomatous, and only the latter were believed to have the potential to progress to carcinoma. However, it is now appreciated that a subset of serrated polyps also appear to have malignant potential. Serrated polyps are a heterogeneous group of colon polyps that include hyperplastic polyps, sessile serrated adenomas (SSAs), traditional serrated adenomas, and mixed polyps. Insights into these polyps were derived, in part, from studies of patients with the hyperplastic polyposis syndrome. SSAs show a predilection for the right colon, have a distinct histology, and their molecular genetic profile has recently been linked to a pathway for colon tumorigenesis that is characterized by microsatellite instability. Based upon available evidence, it is recommended that patients with serrated adenomas undergo colonoscopic follow-up at the same frequency as for conventional adenomas. It is important that physicians are aware of serrated polyps, particularly serrated adenomas and their relationship to colon cancer, and their proper clinical management.

  3. Disturbance opens recruitment sites for bacterial colonization in activated sludge.

    PubMed

    Vuono, David C; Munakata-Marr, Junko; Spear, John R; Drewes, Jörg E

    2016-01-01

    Little is known about the role of immigration in shaping bacterial communities or the factors that may dictate success or failure of colonization by bacteria from regional species pools. To address these knowledge gaps, the influence of bacterial colonization into an ecosystem (activated sludge bioreactor) was measured through a disturbance gradient (successive decreases in the parameter solids retention time) relative to stable operational conditions. Through a DNA sequencing approach, we show that the most abundant bacteria within the immigrant community have a greater probability of colonizing the receiving ecosystem, but mostly as low abundance community members. Only during the disturbance do some of these bacterial populations significantly increase in abundance beyond background levels and in few cases become dominant community members post-disturbance. Two mechanisms facilitate the enhanced enrichment of immigrant populations during disturbance: (i) the availability of resources left unconsumed by established species and (ii) the increased availability of niche space for colonizers to establish and displace resident populations. Thus, as a disturbance decreases local diversity, recruitment sites become available to promote colonization. This work advances our understanding of microbial resource management and diversity maintenance in complex ecosystems. PMID:25727891

  4. Multicongenic fate mapping quantification of dynamics of thymus colonization.

    PubMed

    Ziętara, Natalia; Łyszkiewicz, Marcin; Puchałka, Jacek; Witzlau, Katrin; Reinhardt, Annika; Förster, Reinhold; Pabst, Oliver; Prinz, Immo; Krueger, Andreas

    2015-09-21

    Postnatal T cell development depends on continuous colonization of the thymus by BM-derived T lineage progenitors. Both quantitative parameters and the mechanisms of thymus seeding remain poorly understood. Here, we determined the number of dedicated thymus-seeding progenitor niches (TSPNs) capable of supporting productive T cell development, turnover rates of niche occupancy, and feedback mechanisms. To this end, we established multicongenic fate mapping combined with mathematical modeling to quantitate individual events of thymus colonization. We applied this method to study thymus colonization in CCR7(-/-)CCR9(-/-) (DKO) mice, whose TSPNs are largely unoccupied. We showed that ∼160-200 TSPNs are present in the adult thymus and, on average, 10 of these TSPNs were open for recolonization at steady state. Preconditioning of wild-type mice revealed a similar number of TSPNs, indicating that preconditioning can generate space efficiently for transplanted T cell progenitors. To identify potential cellular feedback loops restricting thymus colonization, we performed serial transfer experiments. These experiments indicated that thymus seeding was directly restricted by the duration of niche occupancy rather than long-range effects, thus challenging current paradigms of thymus colonization. PMID:26347471

  5. Colonic atresia in cattle: A prospective study of 43 cases

    PubMed Central

    Ducharme, Norm G.; Arighi, Mimi; Horney, F. Don; Barker, Ian K.; Livesey, Michael A.; Hurtig, Mark H.; Johnson, Roger P.

    1988-01-01

    This prospective study was initiated to document the success rate obtained in the treatment of colonic atresia in calves, identify factors that influence survival rate, and to report the histopathological appearance of the proximal blind end of the ascending colon. Forty-three calves with intestinal obstruction due to colonic atresia were admitted to the Ontario Veterinary College between September 1982 and May 1986. Parameters recorded prospectively in this study included age, breed, sex, history, vital signs, acid-base and electrolyte status, location of intestinal atresia, medical and surgical management, and outcome. The typical history and clinical signs included failure to pass meconium or feces, decreased appetite, and progressive depression and abdominal distension. The most common site of colonic atresia was the midportion of the spiral loop of the ascending colon (n = 25). Of the 43 calves, three (7%) were euthanized at surgery, 21 (49%) died in the hospital, and 19 (44%) survived and were discharged from the hospital. Four of the surviving calves died subsequent to discharge giving an overall long-term (mean 15.9 months) survival rate of 35%. No significant risk factors were identified, although experienced surgeons showed a trend towards increased survival rate. ImagesFigure 2.Figure 3.Figure 4.Figure 5. PMID:17423141

  6. Multicongenic fate mapping quantification of dynamics of thymus colonization

    PubMed Central

    Łyszkiewicz, Marcin; Puchałka, Jacek; Witzlau, Katrin; Reinhardt, Annika; Förster, Reinhold; Pabst, Oliver; Prinz, Immo

    2015-01-01

    Postnatal T cell development depends on continuous colonization of the thymus by BM-derived T lineage progenitors. Both quantitative parameters and the mechanisms of thymus seeding remain poorly understood. Here, we determined the number of dedicated thymus-seeding progenitor niches (TSPNs) capable of supporting productive T cell development, turnover rates of niche occupancy, and feedback mechanisms. To this end, we established multicongenic fate mapping combined with mathematical modeling to quantitate individual events of thymus colonization. We applied this method to study thymus colonization in CCR7−/−CCR9−/− (DKO) mice, whose TSPNs are largely unoccupied. We showed that ∼160–200 TSPNs are present in the adult thymus and, on average, 10 of these TSPNs were open for recolonization at steady state. Preconditioning of wild-type mice revealed a similar number of TSPNs, indicating that preconditioning can generate space efficiently for transplanted T cell progenitors. To identify potential cellular feedback loops restricting thymus colonization, we performed serial transfer experiments. These experiments indicated that thymus seeding was directly restricted by the duration of niche occupancy rather than long-range effects, thus challenging current paradigms of thymus colonization. PMID:26347471

  7. Multicongenic fate mapping quantification of dynamics of thymus colonization.

    PubMed

    Ziętara, Natalia; Łyszkiewicz, Marcin; Puchałka, Jacek; Witzlau, Katrin; Reinhardt, Annika; Förster, Reinhold; Pabst, Oliver; Prinz, Immo; Krueger, Andreas

    2015-09-21

    Postnatal T cell development depends on continuous colonization of the thymus by BM-derived T lineage progenitors. Both quantitative parameters and the mechanisms of thymus seeding remain poorly understood. Here, we determined the number of dedicated thymus-seeding progenitor niches (TSPNs) capable of supporting productive T cell development, turnover rates of niche occupancy, and feedback mechanisms. To this end, we established multicongenic fate mapping combined with mathematical modeling to quantitate individual events of thymus colonization. We applied this method to study thymus colonization in CCR7(-/-)CCR9(-/-) (DKO) mice, whose TSPNs are largely unoccupied. We showed that ∼160-200 TSPNs are present in the adult thymus and, on average, 10 of these TSPNs were open for recolonization at steady state. Preconditioning of wild-type mice revealed a similar number of TSPNs, indicating that preconditioning can generate space efficiently for transplanted T cell progenitors. To identify potential cellular feedback loops restricting thymus colonization, we performed serial transfer experiments. These experiments indicated that thymus seeding was directly restricted by the duration of niche occupancy rather than long-range effects, thus challenging current paradigms of thymus colonization.

  8. Parameters affecting solvent production by Clostridium pasteurianum

    SciTech Connect

    Dabrock, B.; Bahl, H.; Gottschalk, G. )

    1992-04-01

    The effect of pH, growth rate, phosphate and iron limitation, carbon monoxide, and carbon source on product formation by Clostridium pasteurianum was determined. Under phosphate limitation, glucose was fermented almost exclusively to acetate and butyrate independently of the pH and growth rate. Iron limitation caused lactate production (38 mol/100 mol) from glucose in batch and continuous culture. At 15% (vol/vol) carbon monoxide in the atmosphere, glucose was fermented to ethanol (24 mol/100 mol), lactate (32 mol/100 mol), and butanol (36 mol/100 mol) in addition to the usual products, acetate (38 mol/100 mol) and butyrate (17 mol/100 mol). During glycerol fermentation, a completely different product pattern was found. In continuous culture under phosphate limitation, acetate and butyrate were produced only in trace amounts, whereas ethanol (30 mol/10 mol), butanol (18 mol/100 mol), and 1,3-propanediol (18 mol/100 mol) were the major products. Under iron limitation, the ratio of these products could be changed in favor of 1,3-propanediol (34 mol/100 mol). In addition, lactate was produced in significant amounts (25 mol/100 mol). The tolerance of C. pasteurianum to glycerol was remarkably high; growth was not inhibited by glycerol concentrations up to 17% (wt/vol). Increasing glycerol concentrations favored the production of 1,3-propanediol.

  9. Physical stress and bacterial colonization

    PubMed Central

    Otto, Michael

    2014-01-01

    Bacterial surface colonizers are subject to a variety of physical stresses. During the colonization of human epithelia such as on the skin or the intestinal mucosa, bacteria mainly have to withstand the mechanical stress of being removed by fluid flow, scraping, or epithelial turnover. To that end, they express a series of molecules to establish firm attachment to the epithelial surface, such as fibrillar protrusions (pili) and surface-anchored proteins that bind to human matrix proteins. In addition, some bacteria – in particular gut and urinary tract pathogens – use internalization by epithelial cells and other methods such as directed inhibition of epithelial turnover to ascertain continued association with the epithelial layer. Furthermore, many bacteria produce multi-layered agglomerations called biofilms with a sticky extracellular matrix, providing additional protection from removal. This review will give an overview over the mechanisms human bacterial colonizers have to withstand physical stresses with a focus on bacterial adhesion. PMID:25212723

  10. Bacterial colonization of percutaneous sutures.

    PubMed

    Gristina, A G; Price, J L; Hobgood, C D; Webb, L X; Costerton, J W

    1985-07-01

    The direct electron microscopic examination of 15 sutures and 15 staples removed from 10 healed surgical wounds showed, on the intradermal portions, consistent colonization by bacteria growing in adherent biofilms. This clearly demonstrable bacterial colonization of biomaterials within the wound tract had not resulted in infection or perceptible inflammation in any of the wounds. These bacterial cells were of several morphotypes, including gram-positive cocci, and all specimens yielded cultures of the autochthonous (native) skin bacterium, Staphylococcus epidermidis. The bacteria within the wound tracts were enveloped by extracellular material that appeared on scanning electron microscopy to be a condensed amorphous residue and on transmission electron microscopy to be a fibrous extracellular matrix. We suggest that this mode of growth, in which the colonizing bacteria are enveloped in a copious exopolysaccharide glycocalix, protects the bacteria from host defense factors and accounts for their persistence on the suture surfaces until they are removed with the sutures.

  11. Physical stress and bacterial colonization.

    PubMed

    Otto, Michael

    2014-11-01

    Bacterial surface colonizers are subject to a variety of physical stresses. During the colonization of human epithelia such as on the skin or the intestinal mucosa, bacteria mainly have to withstand the mechanical stress of being removed by fluid flow, scraping, or epithelial turnover. To that end, they express a series of molecules to establish firm attachment to the epithelial surface, such as fibrillar protrusions (pili) and surface-anchored proteins that bind to human matrix proteins. In addition, some bacteria--in particular gut and urinary tract pathogens--use internalization by epithelial cells and other methods such as directed inhibition of epithelial turnover to ascertain continued association with the epithelial layer. Furthermore, many bacteria produce multilayered agglomerations called biofilms with a sticky extracellular matrix, providing additional protection from removal. This review will give an overview over the mechanisms human bacterial colonizers have to withstand physical stresses with a focus on bacterial adhesion.

  12. Biomarkers of human colonic cell growth are influenced differently by a history of colonic neoplasia and the consumption of acarbose.

    PubMed

    Weaver, G A; Tangel, C T; Krause, J A; Parfitt, M M; Stragand, J J; Jenkins, P L; Erb, T A; Davidson, R H; Alpern, H D; Guiney, W B; Higgins, P J

    2000-11-01

    The nutritional effects of butyrate on the colonic mucosa and studies of transformed cells suggest that butyrate has anti-colon cancer effects. If butyrate has antineoplastic effects, mucosal growth contrasts between normal subjects and those with a history of colonic neoplasia would parallel changes in growth characteristics caused by butyrate in a colon neoplasia population. To test this hypothesis, rectal biopsies from a survey of colonoscopy patients (n = 50) with and without a history of colonic neoplasia (controls) were compared. Similarly, rectal biopsies were compared from subjects (n = 44) with a colon neoplasia history in an acarbose-placebo crossover trial. Control subjects in the colonoscopy survey had higher bromodeoxyuridine (BrdU) uptake than subjects with a history of neoplasia (P = 0.05). The control subjects also had a higher correlation of BrdU and Ki-67 labeling (P = 0.003). Both findings were paralleled by acarbose use. Acarbose augmented BrdU uptake (P = 0.0001) and improved the correlation of BrdU and Ki-67 labeling (P = 0.013). Acarbose also augmented fecal butyrate (P = 0.0001), which was positively correlated with Ki-67 labeling (P = 0.003). p52 antigen had an earlier pattern of crypt distribution in subjects with a history of colon neoplasia but was not affected by acarbose use. Lewis-Y antigen was expressed earlier in the crypt with acarbose but had similar expression in the colonoscopy survey groups. The use of acarbose to enhance fecal butyrate concentration produced mucosal changes paralleling the findings in control subjects as opposed to those with neoplasia, supporting the concept of an antineoplastic role for butyrate.

  13. EphrinA5 suppresses colon cancer development by negatively regulating epidermal growth factor receptor stability.

    PubMed

    Wang, Tong-Hong; Chang, Junn-Liang; Ho, Jar-Yi; Wu, Hsiao-Chun; Chen, Tse-Ching

    2012-01-01

    Colon cancer is one of the most common human cancers worldwide. Owing to its aggressiveness and lethality, it is necessary to determine the mechanisms regulating the carcinogenesis of colon cancer. EphrinA5 has been reported to act as a putative tumor suppressor in glioma; however, little is known concerning the role of this protein in the context of colon cancer. To elucidate the biological significance of ephrinA5 in colon cancer, we examined ephrinA5 and epidermal growth factor receptor (EGFR) expression profiles in both colon cancer and normal tissues, using immunohistochemistry on a 96-spot tissue microarray. Gain-of-function and loss-of-function experiments were performed on the human colon cancer cell lines SW480 and WiDr to determine the biological effects of ephrinA5 in relation to cell proliferation, survival, and migration. It was found that ephrinA5 mRNA and protein levels were significantly reduced in colon cancer as compared with normal colon tissue specimens. EphrinA5 expression was also negatively associated with tumor differentiation and clinical stage. In colon cancer cell line models, ephrinA5 exerted an inhibitory effect on EGFR by promoting c-Cbl-mediated EGFR ubiquitination and degradation. EphrinA5 did not affect the transcriptional regulation of EGFR mRNA expression in colon cancer cells. Expression of ephrinA5 suppressed colon cancer cell proliferation, migration, and chemotherapeutic resistance. In conclusion, ephrinA5 inhibited colon cancer progression by promoting c-Cbl-mediated EGFR degradation. Our findings identify a novel mechanism that could be utilized to improve the therapeutic efficiency of EGFR-targeting strategies.

  14. Drugs Approved for Colon and Rectal Cancer

    MedlinePlus

    ... Professionals Questions to Ask about Your Treatment Research Drugs Approved for Colon and Rectal Cancer This page ... and rectal cancer that are not listed here. Drugs Approved for Colon Cancer Avastin (Bevacizumab) Bevacizumab Camptosar ( ...

  15. Teaching about the Colonization of Space.

    ERIC Educational Resources Information Center

    Huebner, Jay S.

    1979-01-01

    Describes an undergraduate course, The Colonization of Space, which introduces nonscience majors at the University of North Florida to current topics in the exploration, industrialization, and colonization of space. References to the audiovisual resources and literature are also included. (HM)

  16. Breast and Colon Cancer Family Registries

    Cancer.gov

    The Breast Cancer Family Registry and the Colon Cancer Family Registry were established by the National Cancer Institute as a resource for investigators to use in conducting studies on the genetics and molecular epidemiology of breast and colon cancer.

  17. Taxon interactions control the distributions of cryoconite bacteria colonizing a High Arctic ice cap.

    PubMed

    Gokul, Jarishma K; Hodson, Andrew J; Saetnan, Eli R; Irvine-Fynn, Tristram D L; Westall, Philippa J; Detheridge, Andrew P; Takeuchi, Nozomu; Bussell, Jennifer; Mur, Luis A J; Edwards, Arwyn

    2016-08-01

    Microbial colonization of glacial ice surfaces incurs feedbacks which affect the melting rate of the ice surface. Ecosystems formed as microbe-mineral aggregates termed cryoconite locally reduce ice surface albedo and represent foci of biodiversity and biogeochemical cycling. Consequently, greater understanding the ecological processes in the formation of functional cryoconite ecosystems upon glacier surfaces is sought. Here, we present the first bacterial biogeography of an ice cap, evaluating the respective roles of dispersal, environmental and biotic filtration occurring at local scales in the assembly of cryoconite microbiota. 16S rRNA gene amplicon semiconductor sequencing of cryoconite colonizing a Svalbard ice cap coupled with digital elevation modelling of physical parameters reveals the bacterial community is dominated by a ubiquitous core of generalist taxa, with evidence for a moderate pairwise distance-decay relationship. While geographic position and melt season duration are prominent among environmental predictors of community structure, the core population of taxa appears highly influential in structuring the bacterial community. Taxon co-occurrence network analysis reveals a highly modular community structured by positive interactions with bottleneck taxa, predominantly Actinobacteria affiliated to isolates from soil humus. In contrast, the filamentous cyanobacterial taxon (assigned to Leptolyngbya/Phormidesmis pristleyi) which dominates the community and binds together granular cryoconite are poorly connected to other taxa. While our study targeted one ice cap, the prominent role of generalist core taxa with close environmental relatives across the global cryosphere indicate discrete roles for cosmopolitan Actinobacteria and Cyanobacteria as respective keystone taxa and ecosystem engineers of cryoconite ecosystems colonizing ice caps. PMID:27261672

  18. Colon Cleansing: Health or Hype?

    MedlinePlus

    ... maintain a healthy bacterial composition, known as your microflora. “Your microflora plays a crucial role in protecting your body ... potassium Kidney damage Plus, colon cleansing changes your microflora. “You may think you’re getting rid of ...

  19. Colon Capsule Endoscopy: Review and Perspectives

    PubMed Central

    Modayil, Rani; Stavropoulos, Stavros

    2016-01-01

    Colon capsule endoscopy utilizing PillCam COLON 2 capsule allows for visualization potentially of the entire colon and is currently approved for patients who cannot withstand the rigors of traditional optical colonoscopy (OC) and associated sedation as well as those that had an OC that was incomplete for technical reasons other than a poor preparation. We will then describe the prior experience and current status of colon capsule endoscopy. PMID:27698664

  20. Arbuscular mycorrhizal colonization, plant chemistry, and aboveground herbivory on Senecio jacobaea

    NASA Astrophysics Data System (ADS)

    Reidinger, Stefan; Eschen, René; Gange, Alan C.; Finch, Paul; Bezemer, T. Martijn

    2012-01-01

    Arbuscular mycorrhizal fungi (AMF) can affect insect herbivores by changing plant growth and chemistry. However, many factors can influence the symbiotic relationship between plant and fungus, potentially obscuring experimental treatments and ecosystem impacts. In a field experiment, we assessed AMF colonization levels of individual ragwort ( Senecio jacobaea) plants growing in grassland plots that were originally sown with 15 or 4 plant species, or were unsown. We measured the concentrations of carbon, nitrogen and pyrrolizidine alkaloids (PAs), and assessed the presence of aboveground insect herbivores on the sampled plants. Total AMF colonization and colonization by arbuscules was lower in plots sown with 15 species than in plots sown with 4 species and unsown plots. AMF colonization was positively related to the cover of oxeye daisy ( Leucanthemum vulgare) and a positive relationship between colonization by arbuscules and the occurrence of a specialist seed-feeding fly ( Pegohylemyia seneciella) was found. The occurrence of stem-boring, leaf-mining and sap-sucking insects was not affected by AMF colonization. Total PA concentrations were negatively related to colonization levels by vesicles, but did not differ among the sowing treatments. No single factor explained the observed differences in AMF colonization among the sowing treatments or insect herbivore occurrence on S. jacobaea. However, correlations across the treatments suggest that some of the variation was due to the abundance of one plant species, which is known to stimulate AMF colonization of neighbouring plants, while AMF colonization was related to the occurrence of a specialist insect herbivore. Our results thus illustrate that in natural systems, the ecosystem impact of AMF through their influence on the occurrence of specialist insects can be recognised, but they also highlight the confounding effect of neighbouring plant species identity. Hence, our results emphasise the importance of field

  1. Evaluating Darwin's naturalization hypothesis in experimental plant assemblages: phylogenetic relationships do not determine colonization success.

    PubMed

    Castro, Sergio A; Escobedo, Victor M; Aranda, Jorge; Carvallo, Gastón O

    2014-01-01

    Darwin's naturalization hypothesis (DNH) proposes that colonization is less likely when the colonizing species is related to members of the invaded community, because evolutionary closeness intensifies competition among species that share similar resources. Studies that have evaluated DNH from correlational evidence have yielded controversial results with respect to its occurrence and generality. In the present study we carried out a set of manipulative experiments in which we controlled the phylogenetic relatedness of one colonizing species (Lactuca sativa) with five assemblages of plants (the recipient communities), and evaluated the colonizing success using five indicators (germination, growth, flowering, survival, and recruitment). The evolutionary relatedness was calculated as the mean phylogenetic distance between Lactuca and the members of each assemblage (MPD) and by the mean phylogenetic distance to the nearest neighbor (MNND). The results showed that the colonization success of Lactuca was not affected by MPD or MNND values, findings that do not support DNH. These results disagree with experimental studies made with communities of microorganisms, which show an inverse relation between colonization success and phylogenetic distances. We suggest that these discrepancies may be due to the high phylogenetic distance used, since in our experiments the colonizing species (Lactuca) was a distant relative of the assemblage members, while in the other studies the colonizing taxa have been related at the congeneric and conspecific levels. We suggest that under field conditions the phylogenetic distance is a weak predictor of competition, and it has a limited role in determining colonization success, contrary to prediction of the DNH. More experimental studies are needed to establish the importance of phylogenetic distance between colonizing species and invaded community on colonization success.

  2. Pineal gland function is required for colon antipreneoplastic effects of physical exercise in rats.

    PubMed

    Frajacomo, F T T; de Paula Garcia, W; Fernandes, C R; Garcia, S B; Kannen, V

    2015-10-01

    Light-at-night exposure enhances the risk of cancer. Colon cancer is among the most dangerous tumors affecting humankind. Physical exercise has shown positive effects against colon cancer. Here, we investigated whether pineal gland modulates antipreneoplastic effects of physical exercise in the colon. Surgical and non-surgical pineal impairments were performed to clarify the relationship between the pineal gland activity and manifestation of colonic preneoplastic lesions. Next, a progressive swimming training was applied in rats exposed or not to either non-surgical pineal impairment or carcinogen treatment for 10 weeks. Both surgical and non-surgical pineal impairments increased the development of colon preneoplasia. It was further found that impairing the pineal gland function, higher rates of DNA damage were induced in colonic epithelial and enteric glial cells. Physical exercise acted positively against preneoplasia, whereas impairing the pineal function with constant light exposure disrupts its positive effects on the development of preneoplastic lesions in the colon. This was yet related to increased DNA damage in glial cells and enteric neuronal activation aside from serum melatonin levels. Our findings suggest that protective effects of physical exercise against colon cancer are dependent on the pineal gland activity.

  3. Trade-off between competition and facilitation defines gap colonization in mountains.

    PubMed

    Lembrechts, Jonas J; Milbau, Ann; Nijs, Ivan

    2015-11-10

    Recent experimental observations show that gap colonization in small-stature (e.g. grassland and dwarf shrubs) vegetation strongly depends on the abiotic conditions within them. At the same time, within-gap variation in biotic interactions such as competition and facilitation, caused by distance to the gap edge, would affect colonizer performance, but a theoretical framework to explore such patterns is missing. Here, we model how competition, facilitation and environmental conditions together determine the small-scale patterns of gap colonization along a cold gradient in mountains, by simulating colonizer survival in gaps of various sizes. Our model adds another dimension to the known effects of biotic interactions along a stress gradient by focussing on the trade-off between competition and facilitation in the within-gap environment. We show that this trade-off defines a peak in colonizer survival at a specific distance from the gap edge, which progressively shifts closer to the edge as the environment gets colder, ultimately leaving a large fraction of gaps unsuitable for colonization in facilitation-dominated systems. This is reinforced when vegetation size and temperature amelioration are manipulated simultaneously with temperature in order to simulate an elevational gradient more realistically. Interestingly, all other conditions being equal, the magnitude of the realized survival peak was always lower in large than in small gaps, making large gaps harder to colonize. The model is relevant to predict effects of non-native plant invasions and climate warming on colonization processes in mountains.

  4. Trade-off between competition and facilitation defines gap colonization in mountains

    PubMed Central

    Lembrechts, Jonas J.; Milbau, Ann; Nijs, Ivan

    2015-01-01

    Recent experimental observations show that gap colonization in small-stature (e.g. grassland and dwarf shrubs) vegetation strongly depends on the abiotic conditions within them. At the same time, within-gap variation in biotic interactions such as competition and facilitation, caused by distance to the gap edge, would affect colonizer performance, but a theoretical framework to explore such patterns is missing. Here, we model how competition, facilitation and environmental conditions together determine the small-scale patterns of gap colonization along a cold gradient in mountains, by simulating colonizer survival in gaps of various sizes. Our model adds another dimension to the known effects of biotic interactions along a stress gradient by focussing on the trade-off between competition and facilitation in the within-gap environment. We show that this trade-off defines a peak in colonizer survival at a specific distance from the gap edge, which progressively shifts closer to the edge as the environment gets colder, ultimately leaving a large fraction of gaps unsuitable for colonization in facilitation-dominated systems. This is reinforced when vegetation size and temperature amelioration are manipulated simultaneously with temperature in order to simulate an elevational gradient more realistically. Interestingly, all other conditions being equal, the magnitude of the realized survival peak was always lower in large than in small gaps, making large gaps harder to colonize. The model is relevant to predict effects of non-native plant invasions and climate warming on colonization processes in mountains. PMID:26558706

  5. Transverse Colon Diverticulitis with Calcified Fecalith

    PubMed Central

    Solak, Aynur; Solak, Ilhami; Genç, Berhan; Sahin, Neslin; Yalaz, Seyhan

    2013-01-01

    Left colonic diverticula are common in Western populations, whereas right colonic diverticulosis primarily occurs in Oriental populations. Diverticulitis of the transverse colon is very rare, with very few cases reported in the literature. Herein, we report a case of transverse colon diverticulitis caused by a calcified stone in a 69-year-old female. This was a solitary diverticulum. The signs and symptoms of the disease are similar to acute pancreatitis. To the best of our knowledge, this is the first report describing the MRI findings of a patient with trans-verse colon diverticulitis caused by a calcified stone. PMID:25610254

  6. Volumetric Colon Wall Unfolding Using Harmonic Differentials

    PubMed Central

    Zeng, Wei; Marino, Joseph; Kaufman, Arie; Gu, Xianfeng David

    2011-01-01

    Volumetric colon wall unfolding is a novel method for virtual colon analysis and visualization with valuable applications in virtual colonoscopy (VC) and computer-aided detection (CAD) systems. A volumetrically unfolded colon enables doctors to visualize the entire colon structure without occlusions due to haustral folds, and is critical for performing efficient and accurate texture analysis on the volumetric colon wall. Though conventional colon surface flattening has been employed for these uses, volumetric colon unfolding offers the advantages of providing the needed quantities of information with needed accuracy. This work presents an efficient and effective volumetric colon unfolding method based on harmonic differentials. The colon volumes are reconstructed from CT images and are represented as tetrahedral meshes. Three harmonic 1-forms, which are linearly independent everywhere, are computed on the tetrahedral mesh. Through integration of the harmonic 1-forms, the colon volume is mapped periodically to a canonical cuboid. The method presented is automatic, simple, and practical. Experimental results are reported to show the performance of the algorithm on real medical datasets. Though applied here specifically to the colon, the method is general and can be generalized for other volumes. PMID:21765563

  7. [Lactobacilli and colon carcinoma--A review].

    PubMed

    Wang, Shumei; Zhang, Lanwei; Shan, Yujuan

    2015-06-01

    Epidemiological studies showed that incidence of colon carcinoma is increased in the world. There are many difficulties to inhibit colon carcinoma because the causes of inducing colon carcinoma were various and interactive each other. Previous evidence supported the balance of the colonic microflora was critical in inhibiting colon carcinoma and the protection by colonic microflora could be improved by ingesting lactobacilli. Therefore, the biological functions and anticancer effects of lactobacilli attract attention of researchers. In this review we discussed the causes of colon carcinoma; the anticancer mechanisms of lactobacilli on the basis of our own studies. Eventually, we summarized the effects of anticancer of different components and metabolic products extracted from lactobacilli. PMID:26562990

  8. Mechanical properties of the rat colon: the effect of age, sex and different conditions of storage.

    PubMed

    Watters, D A; Smith, A N; Eastwood, M A; Anderson, K C; Elton, R A

    1985-01-01

    The mechanical properties of the rat colon were studied in old and young Sprague-Dawley rats which were also grouped by sex. Different storage media were used. Rings of colonic tissue were submitted to pulls on an Instron 1026 tensiometer. Gender did not affect the properties of the young rat colon. The rat colon has a tensile strength of around 50 g/mm2 (which places it between the dog and the cat). It increased in strength from proximal to distal, though the rectum was weaker than the colon. The pre-strain of the rat colon was 10% and it was capable of stretching to 200% of its original dimensions. The strength and ability to stretch fell with age, although it initially increased, in the first year of life. Physiological saline at 4 degrees C preserved the burst strength, percentage elongation, hysteresis and Young's modulus between 25 and 100 g stress for up to 1 week. Young's modulus between 125 and 200 g fell progressively with each day of storage. Stress relaxation rose in the first 24 h and thereafter remained constant. Salt appeared to be a good long-term storage medium. Irradiation of the colons before storage did not affect the mechanical properties.

  9. Caesium inhibits the colonization of Medicago truncatula by arbuscular mycorrhizal fungi.

    PubMed

    Wiesel, Lea; Dubchak, Sergiy; Turnau, Katarzyna; Broadley, Martin R; White, Philip J

    2015-03-01

    Contamination of soils with radioisotopes of caesium (Cs) is of concern because of their emissions of harmful β and γ radiation. Radiocaesium enters the food chain through vegetation and the intake of Cs can affect the health of organisms. Arbuscular mycorrhizal (AM) fungi form mutualistic symbioses with plants through colonization of the roots and previous studies on the influence of AM on Cs concentrations in plants have given inconsistent results. These studies did not investigate the influence of Cs on AM fungi and it is therefore not known if Cs has a direct effect on AM colonization. Here, we investigated whether Cs influences AM colonization and if this effect impacts on the influence of Rhizophagus intraradices on Cs accumulation by Medicago truncatula. M. truncatula was grown with or without R. intraradices in pots containing different concentrations of Cs. Here, we present the first evidence that colonization of plants by AM fungi can be negatively affected by increasing Cs concentrations in the soil. Mycorrhizal colonization had little effect on root or shoot Cs concentrations. In conclusion, the colonization by AM fungi is impaired by high Cs concentrations and this direct effect of soil Cs on AM colonization might explain the inconsistent results reported in literature that have shown increased, decreased or unaffected Cs concentrations in AM plants.

  10. Single cutaneous metastasis of colon adenocarcinoma - Case report*

    PubMed Central

    Góes, Heliana Freitas de Oliveira; Lima, Caren dos Santos; de Souza, Mariana Boechat; Estrella, Rogério Ribeiro; Faria, Mônica Ali Novaes; Rochael, Mayra Carrijo

    2016-01-01

    Skin metastases are relatively rare and occur most often when the cancer is already advanced, invading other organs. As to location, they often seem to elect areas located close to the primary tumor, although distant sites, such as the scalp, may be affected with some frequency. We present a case of a 76-year-old woman with colon adenocarcinoma that had a single metastatic lesion on the scalp. PMID:27579752

  11. Detection of colon and rectum cancers by terahertz techniques

    NASA Astrophysics Data System (ADS)

    Wahaia, Faustino; Valusis, Gintaras; Bernardo, Luis M.; Oliveira, Albino; Macutkevic, Jan; Kasalynas, Irmantas; Seliuta, Dalius

    2010-04-01

    Based on experimental analyses of colon and rectal tissues by THz spectroscopy and THz imaging, we show it is possible to distinguish between healthy and cancerous zones. Plots of the absorption coefficient and the index of refraction of the healthy and cancer affected tissues as well as 2-D transmission THz images will be presented. The experimental results will be discussed and the conditions for the tissues discrimination will be established.

  12. Personalizing Colon Cancer Therapeutics: Targeting Old and New Mechanisms of Action

    PubMed Central

    Kline, Christina Leah B.; El-Deiry, Wafik S.

    2013-01-01

    The use of pharmaceuticals for colon cancer treatment has been increasingly personalized, in part due to the development of new molecular tools. In this review, we discuss the old and new colon cancer chemotherapeutics, and the parameters that have been shown to be predictive of efficacy and safety of these chemotherapeutics. In addition, we discuss how alternate pharmaceuticals have been developed in light of a potential lack of response or resistance to a particular chemotherapeutic. PMID:24276379

  13. Pneumoretroperitoneum and Pneumomediastinum Revealing a Left Colon Perforation

    PubMed Central

    Montori, Giulia; Di Giovanni, Giacomo; Mzoughi, Zeineb; Angot, Cedric; Al Samman, Sophie; Solaini, Leonardo; Cheynel, Nicolas

    2015-01-01

    Left colon perforation usually occurs in complicated diverticulitis or cancer. The most frequent signs are intraperitoneal abscess or peritonitis. In cases of retroperitoneal colonic perforation, diagnosis may be difficult. A 59-year-old woman presented with left thigh pain and with abdominal discomfort associated with mild dyspnea. Computed tomography scan showed air bubbles and purulent collection in the retroperitoneum, with subcutaneous emphysema extending from the left thigh to the neck. Computed tomography scan also revealed portal vein gas and thrombosis with multiple liver abscesses. An emergency laparotomy revealed a perforation of the proximal left colon. No masses were found. A left colectomy was performed. The retroperitoneum was drained and washed extensively. A negative pressure wound therapy was applied. A second-look laparotomy was performed 48 hours later. The retroperitoneum was drained and an end colostomy was performed. Intensive Care Unit postoperative stay was 9 days, and the patient was discharged on the 32nd postoperative day. Pneumoretroperitoneum and pneumomediastinum are rare signs of colonic retroperitoneal perforation. The diagnosis may be delayed, especially in the absence of peritoneal irritation. Clinical, laboratory, and especially radiologic parameters might be useful. Surgical treatment must be prompt to improve prognosis. PMID:26414818

  14. Pneumoretroperitoneum and Pneumomediastinum Revealing a Left Colon Perforation.

    PubMed

    Montori, Giulia; Di Giovanni, Giacomo; Mzoughi, Zeineb; Angot, Cedric; Al Samman, Sophie; Solaini, Leonardo; Cheynel, Nicolas

    2015-06-01

    Left colon perforation usually occurs in complicated diverticulitis or cancer. The most frequent signs are intraperitoneal abscess or peritonitis. In cases of retroperitoneal colonic perforation, diagnosis may be difficult. A 59-year-old woman presented with left thigh pain and with abdominal discomfort associated with mild dyspnea. Computed tomography scan showed air bubbles and purulent collection in the retroperitoneum, with subcutaneous emphysema extending from the left thigh to the neck. Computed tomography scan also revealed portal vein gas and thrombosis with multiple liver abscesses. An emergency laparotomy revealed a perforation of the proximal left colon. No masses were found. A left colectomy was performed. The retroperitoneum was drained and washed extensively. A negative pressure wound therapy was applied. A second-look laparotomy was performed 48 hours later. The retroperitoneum was drained and an end colostomy was performed. Intensive Care Unit postoperative stay was 9 days, and the patient was discharged on the 32nd postoperative day. Pneumoretroperitoneum and pneumomediastinum are rare signs of colonic retroperitoneal perforation. The diagnosis may be delayed, especially in the absence of peritoneal irritation. Clinical, laboratory, and especially radiologic parameters might be useful. Surgical treatment must be prompt to improve prognosis.

  15. Urinary pH and urea concentration correlate to the bacterial colonization rate in gastric, colonic, ileal and myoperitoneal bladder augmentation.

    PubMed

    Lauvetz, R W; Monda, J M; Kramer, S A; Husmann, D A

    1995-08-01

    We investigated how various types of augmentation cystoplasty alter the native bacteriostatic properties of urine, particularly urinary urea and pH, in the Sprague-Dawley rat. The augmentation cystoplasties studied included 1 cm.2 and 2 cm.2 patches of colon, ileum and stomach as well as myoperitoneal bladder flaps. Augmentations in order of decreasing incidence of bacteriuria and urinary pH are 2 cm.2 ileal greater than 1 cm.2 ileal greater than 2 cm.2 colonic greater than 1 cm.2 colonic greater than myoperitoneal greater than cystotomy alone greater than 1 cm.2 gastric greater than 2 cm.2 gastric. Urinary urea concentrations were similar between cystotomy alone, and myoperitoneal and gastric augments. In contrast, all colonic and ileal augments had significantly lower urea concentrations compared to the aforementioned groups. Our findings suggest that the type and size of augmentation directly affect urinary pH and urea nitrogen concentration, and the incidence of bacteriuria.

  16. Competition for space during bacterial colonization of a surface.

    PubMed

    Lloyd, Diarmuid P; Allen, Rosalind J

    2015-09-01

    Competition for space is ubiquitous in the ecology of both microorganisms and macro-organisms. We introduce a bacterial model system in which the factors influencing competition for space during colonization of an initially empty habitat can be tracked directly. Using fluorescence microscopy, we follow the fate of individual Escherichia coli bacterial cell lineages as they undergo expansion competition (the race to be the first to colonize a previously empty territory), and as they later compete at boundaries between clonal territories. Our experiments are complemented by computer simulations of a lattice-based model. We find that both expansion competition, manifested as differences in individual cell lag times, and boundary competition, manifested as effects of neighbour cell geometry, can play a role in colonization success, particularly when lineages expand exponentially. This work provides a baseline for investigating how ecological interactions affect colonization of space by bacterial populations, and highlights the potential of bacterial model systems for the testing and development of ecological theory. PMID:26333814

  17. Competition for space during bacterial colonization of a surface

    PubMed Central

    Lloyd, Diarmuid P.; Allen, Rosalind J.

    2015-01-01

    Competition for space is ubiquitous in the ecology of both microorganisms and macro-organisms. We introduce a bacterial model system in which the factors influencing competition for space during colonization of an initially empty habitat can be tracked directly. Using fluorescence microscopy, we follow the fate of individual Escherichia coli bacterial cell lineages as they undergo expansion competition (the race to be the first to colonize a previously empty territory), and as they later compete at boundaries between clonal territories. Our experiments are complemented by computer simulations of a lattice-based model. We find that both expansion competition, manifested as differences in individual cell lag times, and boundary competition, manifested as effects of neighbour cell geometry, can play a role in colonization success, particularly when lineages expand exponentially. This work provides a baseline for investigating how ecological interactions affect colonization of space by bacterial populations, and highlights the potential of bacterial model systems for the testing and development of ecological theory. PMID:26333814

  18. Post larval, short-term, colonization patterns: The effect of substratum complexity across subtidal, adjacent, habitats

    NASA Astrophysics Data System (ADS)

    García-Sanz, Sara; Tuya, Fernando; Navarro, Pablo G.; Angulo-Preckler, Carlos; Haroun, Ricardo J.

    2012-10-01

    Benthic habitats are colonized by organisms from the water column and adjacent habitats. There are, however, variations in the 'acceptability' of any habitat to potential colonists. We assessed whether the structural complexity of artificial substrata affected patterns of short-term colonization of post larval faunal assemblages across subtidal habitats within a coastal landscape. Specifically, we tested whether short-term colonization patterns on 3 types of artificial substrata encompassing a range of complexities, including a leaf-like unit, a cushion-shaped leaf-like unit and a cushion-shaped unit, were consistent across 4 adjacent habitats: macroalgal-dominated bottoms, urchin-grazed barrens, seagrass meadows and sandy patches, at Gran Canaria (eastern Atlantic). A total of 16,174 organisms were collected after 4 weeks and 4 taxonomic groups (Crustacea, Chordata, Echinodermata and Mollusca) dominated the assemblage. Despite considerable among-taxa variability being observed in response to habitat effects, the total abundance of colonizers, as well as the abundance of Arthropoda, Chordata and Echinodermata, was affected by the habitat where collectors were deployed, but did not differ among types of collectors. Similarly, the assemblage structure of colonizers was mainly affected by the habitat, but not by the type of collector; habitat contributed to explain most variation in the assemblage structure of the four dominant taxonomic groups (from ca. 5.44-19.23%), and obscured, in all cases, variation explained by the type of collector. As a result, the variation in short-term colonization patterns of faunal assemblages into artificial collectors was mostly affected by variation associated with habitats rather than by differences in the structural complexity of collectors. The largest abundances of colonizers, particularly Echinodermata, were found on sandy patches relative to other habitats, suggesting that the 'availability', rather than any particular attribute

  19. Label-free detection of tumor markers in a colon carcinoma tumor progression model by confocal Raman microspectroscopy

    NASA Astrophysics Data System (ADS)

    Scalfi-Happ, Claudia; Rück, Angelika; Udart, Martin; Hauser, Carmen; Dürr, Christine; Kriebel, Martin

    2013-06-01

    Living colon carcinoma cells were investigated by confocal Raman microspectroscopy. An in vitro model of tumor progression was established. Evaluation of data sets by cluster analysis reveals that lipid bodies might be a valuable diagnostic parameter for early carcinogenesis.

  20. Risk Factors for Acquisition and Loss of Clostridium difficile Colonization in Hospitalized Patients

    PubMed Central

    Reske, Kimberly A.; Seiler, Sondra; Hink, Tiffany; Kwon, Jennie H.

    2015-01-01

    Asymptomatic colonization may contribute to Clostridium difficile transmission. Few data identify which patients are at risk for colonization. We performed a prospective cohort study of C. difficile colonization and risk factors for C. difficile acquisition and loss in hospitalized patients. Patients admitted to medical or surgical wards at a tertiary care hospital were enrolled; interviews and chart review were performed to determine patient demographics, C. difficile infection (CDI) history, medications, and health care exposures. Stool samples/rectal swabs were collected at enrollment and discharge; stool samples from clinical laboratory tests were also included. Samples were cultured for C. difficile, and the isolates were tested for toxins A and B and ribotyped. Chi-square tests and univariate logistic regression were used for the analyses. Two hundred thirty-five patients were enrolled. Of the patients, 21% were colonized with C. difficile (toxigenic and nontoxigenic) at admission and 24% at discharge. Ribotype 027 accounted for 6% of the strains at admission and 12% at discharge. Of the patients colonized at admission, 78% were also colonized at discharge. Cephalosporin use was associated with C. difficile acquisition (47% of patients who acquired C. difficile versus 25% of patients who did not; P = 0.03). β-lactam–β-lactamase inhibitor combinations were associated with a loss of C. difficile colonization (36% of patients who lost C. difficile colonization versus 8% of patients colonized at both admission and discharge; P = 0.04), as was metronidazole (27% versus 3%; P = 0.03). Antibiotic use affects the epidemiology of asymptomatic C. difficile colonization, including acquisition and loss, and it requires additional study. PMID:25987626

  1. Ischemic Colitis Has a Worse Prognosis When Isolated to the Right Side of the Colon

    PubMed Central

    Sotiriadis, John; Brandt, Lawrence J.; Behin, Daniel S.; Southern, William N.

    2009-01-01

    BACKGROUND In general, ischemic colitis has a very good prognosis, but there is concern that when ischemia affects the right side of the colon in an isolated fashion, the prognosis may not be so favorable. OBJECTIVE The aim of this study was to compare the clinical features and outcomes of ischemia isolated to the right side of the colon with those of ischemia involving other areas of the colon. METHODS A retrospective study was undertaken of patients with colon ischemia hospitalized at the Moses and Weiler Divisions of the Montefiore Medical Center during the interval 1998–2005. Patients were identified using computerized searches of ICD-9 codes for colon ischemia and were divided into two groups: those with isolated right colon ischemia (IRCI) and those with colon ischemia not involving the right colon in an isolated fashion (non-IRCI). Only patients with biopsy-proven ischemic colitis were entered into our study. RESULTS A total of 273 cases of biopsy-proven ischemic colitis were identified, of which 71 (26.0%) were isolated to the right side. Of these IRCI cases, 59.2% had an unfavorable outcome compared with 17.3% of cases of non-ICRI: 54.9% of IRCI patients required surgery compared with 10.9% of non-IRCI patients; mortality in patients with IRCI was 22.5% compared with 11.9% in patients with non-IRCI. CONCLUSIONS A total of 273 cases of biopsy-proven ischemic colitis were identified of which 71 (26.0%) involved only the right side. Patients with IRCI had a worse outcome than those with colon ischemia involving other colon regions, including a fivefold need for surgery and a twofold mortality. PMID:17561968

  2. Vibrio cholerae Response Regulator VxrB Controls Colonization and Regulates the Type VI Secretion System.

    PubMed

    Cheng, Andrew T; Ottemann, Karen M; Yildiz, Fitnat H

    2015-05-01

    Two-component signal transduction systems (TCS) are used by bacteria to sense and respond to their environment. TCS are typically composed of a sensor histidine kinase (HK) and a response regulator (RR). The Vibrio cholerae genome encodes 52 RR, but the role of these RRs in V. cholerae pathogenesis is largely unknown. To identify RRs that control V. cholerae colonization, in-frame deletions of each RR were generated and the resulting mutants analyzed using an infant mouse intestine colonization assay. We found that 12 of the 52 RR were involved in intestinal colonization. Mutants lacking one previously uncharacterized RR, VCA0566 (renamed VxrB), displayed a significant colonization defect. Further experiments showed that VxrB phosphorylation state on the predicted conserved aspartate contributes to intestine colonization. The VxrB regulon was determined using whole genome expression analysis. It consists of several genes, including those genes that create the type VI secretion system (T6SS). We determined that VxrB is required for T6SS expression using several in vitro assays and bacterial killing assays, and furthermore that the T6SS is required for intestinal colonization. vxrB is encoded in a four gene operon and the other vxr operon members also modulate intestinal colonization. Lastly, though ΔvxrB exhibited a defect in single-strain intestinal colonization, the ΔvxrB strain did not show any in vitro growth defect. Overall, our work revealed that a small set of RRs is required for intestinal colonization and one of these regulators, VxrB affects colonization at least in part through its regulation of T6SS genes.

  3. Westernized diets lower arsenic gastrointestinal bioaccessibility but increase microbial arsenic speciation changes in the colon.

    PubMed

    Alava, Pradeep; Du Laing, Gijs; Tack, Filip; De Ryck, Tine; Van De Wiele, Tom

    2015-01-01

    Arsenic (As) is an important contaminant present in food and water. Several studies have indicated that the occurrence of As based skin lesions is significantly different when root and gourd rich diets are consumed compared to meat rich diets. Additionally, urinary As speciation from orally exposed individuals appears to depend on the composition of the diet. These observations imply that diet composition can affect both the bioavailable As fraction as the As speciation in the body. In this study, we used the in vitro gastrointestinal method (IVG) to evaluate how an Asian type diet (fiber rich) and a Western type diet (fat and protein rich), differ in their capability to release inorganic As (iAs(V)) and dimethyl arsinate (DMA(V)) from a rice matrix following gastrointestinal digestion. Moreover, we used a validated dynamic gut simulator to investigate whether diet background affects As metabolism by gut microbiota in a colon environment. An Asian diet background resulted in a larger As bioaccessibility (81.2%) than a Western diet background (63.4%). On the other hand, incubation of As contaminated rice with human colon microbiota in the presence of a Western type diet resulted in a larger amount of hazardous As species - monomethyl arsonite and monomethylmonothio arsonate - to be formed after 48 h. The permeability of these As species (60.5% and 50.5% resp.) across a Caco-2 cell line was significantly higher compared to iAs(V) and DMA(V) (46.5% and 28% resp.). We conclude that dietary background is a crucial parameter to incorporate when predicting bioavailability with bioaccessibility measurements and when assessing health risks from As following oral exposure. PMID:25192650

  4. Westernized diets lower arsenic gastrointestinal bioaccessibility but increase microbial arsenic speciation changes in the colon.

    PubMed

    Alava, Pradeep; Du Laing, Gijs; Tack, Filip; De Ryck, Tine; Van De Wiele, Tom

    2015-01-01

    Arsenic (As) is an important contaminant present in food and water. Several studies have indicated that the occurrence of As based skin lesions is significantly different when root and gourd rich diets are consumed compared to meat rich diets. Additionally, urinary As speciation from orally exposed individuals appears to depend on the composition of the diet. These observations imply that diet composition can affect both the bioavailable As fraction as the As speciation in the body. In this study, we used the in vitro gastrointestinal method (IVG) to evaluate how an Asian type diet (fiber rich) and a Western type diet (fat and protein rich), differ in their capability to release inorganic As (iAs(V)) and dimethyl arsinate (DMA(V)) from a rice matrix following gastrointestinal digestion. Moreover, we used a validated dynamic gut simulator to investigate whether diet background affects As metabolism by gut microbiota in a colon environment. An Asian diet background resulted in a larger As bioaccessibility (81.2%) than a Western diet background (63.4%). On the other hand, incubation of As contaminated rice with human colon microbiota in the presence of a Western type diet resulted in a larger amount of hazardous As species - monomethyl arsonite and monomethylmonothio arsonate - to be formed after 48 h. The permeability of these As species (60.5% and 50.5% resp.) across a Caco-2 cell line was significantly higher compared to iAs(V) and DMA(V) (46.5% and 28% resp.). We conclude that dietary background is a crucial parameter to incorporate when predicting bioavailability with bioaccessibility measurements and when assessing health risks from As following oral exposure.

  5. Colonic diverticular disease. Treatment and prevention.

    PubMed

    Gargallo Puyuelo, Carla J; Sopeña, Federico; Lanas Arbeloa, Angel

    2015-12-01

    Diverticular disease represents the most common disease affecting the colon in the Western world. Most cases remain asymptomatic, but some others will have symptoms or develop complications. The aims of treatment in symptomatic uncomplicated diverticular disease are to prevent complications and reduce the frequency and intensity of symptoms. Fibre, probiotics, mesalazine, rifaximin and their combinations seem to be usually an effective therapy. In the uncomplicated diverticulitis, outpatient management is considered the optimal approach in the majority of patients, and oral antibiotics remain the mainstay of treatment. Admission to hospital and intravenous antibiotic are recommended only when the patient is unable to intake food orally, affected by severe comorbidity or does not improve. However, inpatient management and intravenous antibiotics are necessary in complicated diverticulitis. The role of surgery is also changing. Most diverticulitis-associated abscesses can be treated with antibiotics and/or percutaneous drainage and emergency surgery is considered only in patients with acute peritonitis. Finally, patient related factors, and not the number of recurrences, play the most important role in selecting recipients of elective surgery to avoid recurrences. PMID:25979437

  6. Polymers for Colon Targeted Drug Delivery

    PubMed Central

    Rajpurohit, H.; Sharma, P.; Sharma, S.; Bhandari, A.

    2010-01-01

    The colon targeted drug delivery has a number of important implications in the field of pharmacotherapy. Oral colon targeted drug delivery systems have recently gained importance for delivering a variety of therapeutic agents for both local and systemic administration. Targeting of drugs to the colon via oral administration protect the drug from degradation or release in the stomach and small intestine. It also ensures abrupt or controlled release of the drug in the proximal colon. Various drug delivery systems have been designed that deliver the drug quantitatively to the colon and then trigger the release of drug. This review will cover different types of polymers which can be used in formulation of colon targeted drug delivery systems. PMID:21969739

  7. Primary Isolated Extramedullary Plasmacytoma in the Colon

    PubMed Central

    Lee, Seung-Hyun; Ahn, Byung-Kwon; Baek, Sung-Uhn; Chang, Hee-Kyung

    2013-01-01

    Primary isolated extramedullary plasmacytoma is a rare tumor. Although it commonly involves nasopharynx or upper respiratory tract, only 10% of cases involves the gastrointestinal tract. Stomach and small intestine are the most commonly involved sites in the gastrointestinal tract. Primary isolated extramedullary plasmacytoma of colon is extremely rare. We report a case of 45-year-old man who presented with 1-year history of lower abdominal pain. Colonoscopy showed a colonic stricture about 50 cm from the anal verge. Colonoscopic biopsy showed lymphoid hyperplasia. On computed tomography, enhancing circumferential wall thickening and luminal narrowing with pericolic lymph node enlargement in the transverse colon was identified. Patient underwent extended left hemicolectomy. Histopathologic examination of resected colon identified an isolated primary colonic plasmacytoma of 1.7 cm in diameter with regional lymph node involvement (8/50 positive). To administer adequate treatment, further study about clinical features of primary isolated extramedullary plasmacytoma of colon is necessary.

  8. The Relevance of the Colon to Zinc Nutrition

    PubMed Central

    Gopalsamy, Geetha Lavaniya; Alpers, David H; Binder, Henry J; Tran, Cuong D; Ramakrishna, B S; Brown, Ian; Manary, Mark; Mortimer, Elissa; Young, Graeme P

    2015-01-01

    Globally, zinc deficiency is widespread, despite decades of research highlighting its negative effects on health, and in particular upon child health in low-income countries. Apart from inadequate dietary intake of bioavailable zinc, other significant contributors to zinc deficiency include the excessive intestinal loss of endogenously secreted zinc and impairment in small intestinal absorptive function. Such changes are likely to occur in children suffering from environmental (or tropical) enteropathy (EE)—an almost universal condition among inhabitants of developing countries characterized by morphologic and functional changes in the small intestine. Changes to the proximal gut in environmental enteropathy will likely influence the nature and amount of zinc delivered into the large intestine. Consequently, we reviewed the current literature to determine if colonic absorption of endogenous or exogenous (dietary) zinc could contribute to overall zinc nutriture. Whilst we found evidence that significant zinc absorption occurs in the rodent colon, and is favoured when microbially-fermentable carbohydrates (specifically resistant starch) are consumed, it is unclear whether this process occur in humans and/or to what degree. Constraints in study design in the few available studies may well have masked a possible colonic contribution to zinc nutrition. Furthermore these few available human studies have failed to include the actual target population that would benefit, namely infants affected by EE where zinc delivery to the colon may be increased and who are also at risk of zinc deficiency. In conducting this review we have not been able to confirm a colonic contribution to zinc absorption in humans. However, given the observations in rodents and that feeding resistant starch to children is feasible, definitive studies utilising the dual stable isotope method in children with EE should be undertaken. PMID:25594440

  9. Colon Cancer Metastatic to the Biliary Tree

    PubMed Central

    Clayton, Steven B.; Markow, Michael; Mamel, Jay

    2016-01-01

    Metastasis of colon adenocarcinoma is commonly found in the lung, liver, or peritoneum. Common bile duct (CBD) tumors related to adenomas from familial adenomatous polyposis metastasizing from outside of the gastrointestinal tract have been reported. We report a case of biliary colic due to metastatic colon adenocarcinoma to the CBD. Obstructive jaundice with signs of acalculous cholecystitis on imaging in a patient with a history of colon cancer should raise suspicion for metastasis to CBD. PMID:27144209

  10. Spontaneous colonic adenocarcinoma in marmosets.

    PubMed

    Lushbaugh, C C; Humason, G L; Swartzendruber, D C; Richter, C B; Gengozian, N

    1978-01-01

    We find that colonic adenocarcinoma, which is an extremely rare neoplasm of all animals except man and carcinogen-treated rodents, occurs spontaneously in some marmosets. The cotton-topped Saguinus oedipus oedipus is particularly prone to develop it, but we have found it also at necropsy in Callimico goeldii (Goeldi's marmoset). Numerous metastases to regional lymph nodes develop. The cancers arise de novo in the mucosa and early invade the submucosa and lymphatic apparatus and paracolonic lymph nodes. These findings and the continuing occurrence of this cancer in our colony suggests that the marmoset may be the long-sought primate model for experimental intestinal carcinogenesis.

  11. Developmental pathways in colon cancer

    PubMed Central

    Bertrand, Fred E.; Angus, C. William; Partis, William J.; Sigounas, George

    2012-01-01

    A hallmark of cancer is reactivation/alteration of pathways that control cellular differentiation during developmental processes. Evidence indicates that WNT, Notch, BMP and Hedgehog pathways have a role in normal epithelial cell differentiation, and that alterations in these pathways accompany establishment of the tumorigenic state. Interestingly, there is recent evidence that these pathways are intertwined at the molecular level, and these nodes of intersection may provide opportunities for effective targeted therapies. This review will highlight the role of the WNT, Notch, BMP and Hedgehog pathways in colon cancer. PMID:23032367

  12. Electrosprayed inulin microparticles for microbiota triggered targeting of colon.

    PubMed

    Jain, Arvind K; Sood, Vishesh; Bora, Meghali; Vasita, Rajesh; Katti, Dhirendra S

    2014-11-01

    Inulin, a naturally occurring polysaccharide, was acetylated to make it processable by electrospraying, a facile and single step method for microparticle fabrication. Electrospraying process parameters were optimized for fabrication of spherical and monodisperse indomethacin (IDM) loaded inulin acetate (INA) microparticles. The apparent entrapment efficiency of IDM was determined to be 100%, whereas working encapsulation efficiency was estimated to be 35.39 ± 1.63%. Differential scanning calorimetry and X-ray diffraction analysis confirmed molecular dispersion of IDM in an amorphous state within the INA matrix. Finally, the results from in vitro release study performed in simulated gastro-intestinal fluids demonstrated that IDM was released only in simulated colonic fluid that contained inulinase. Therefore, this study demonstrates that acetylation of inulin does not alter its susceptibility to inulinase and that microparticles fabricated from INA can be developed as a colon targeting drug delivery system.

  13. Electrosprayed inulin microparticles for microbiota triggered targeting of colon.

    PubMed

    Jain, Arvind K; Sood, Vishesh; Bora, Meghali; Vasita, Rajesh; Katti, Dhirendra S

    2014-11-01

    Inulin, a naturally occurring polysaccharide, was acetylated to make it processable by electrospraying, a facile and single step method for microparticle fabrication. Electrospraying process parameters were optimized for fabrication of spherical and monodisperse indomethacin (IDM) loaded inulin acetate (INA) microparticles. The apparent entrapment efficiency of IDM was determined to be 100%, whereas working encapsulation efficiency was estimated to be 35.39 ± 1.63%. Differential scanning calorimetry and X-ray diffraction analysis confirmed molecular dispersion of IDM in an amorphous state within the INA matrix. Finally, the results from in vitro release study performed in simulated gastro-intestinal fluids demonstrated that IDM was released only in simulated colonic fluid that contained inulinase. Therefore, this study demonstrates that acetylation of inulin does not alter its susceptibility to inulinase and that microparticles fabricated from INA can be developed as a colon targeting drug delivery system. PMID:25129739

  14. Massive colonic haematoma following blunt trauma sustained playing rugby

    PubMed Central

    Rankin, Alan; Awwad, Amir; Harding, Brendan

    2009-01-01

    A case is presented of a 24-year-old man who sustained a forceful blow to the right side of the abdomen during a tackle while playing rugby union. The patient was thought to be “winded” and could not play on. He sought medical attention several hours later at the local hospital where initial evaluation revealed mild right iliac fossa tenderness with no signs of peritonism and clinical parameters showed haemodynamic stability. Subsequent ultrasound and CT evaluation revealed a large haematoma involving the caecum and ascending colon. Emergency right haemicolectomy with primary anastomosis was performed to remove the large haematoma within the intact colonic wall. He was observed in the high dependency unit and was discharged after 7 days following an uneventful postoperative course. He continues to make significant progress some 3 months later and a full return to contact sport is being proposed within 9–12 months. PMID:21754953

  15. Quantitative measurement of feline colonic transit

    SciTech Connect

    Krevsky, B.; Somers, M.B.; Maurer, A.H.; Malmud, L.S.; Knight, L.C.; Fisher, R.S.

    1988-10-01

    Colonic transit scintigraphy, a method for quantitatively evaluating the movement of the fecal stream in vivo, was employed to evaluate colonic transit in the cat. Scintigraphy was performed in duplicate in five cats and repeated four times in one cat. After instillation of an 111In marker into the cecum through a surgically implanted silicone cecostomy tube, colonic movement of the instillate was quantitated for 24 h using gamma scintigraphy. Antegrade and retrograde motion of radionuclide was observed. The cecum and ascending colon emptied rapidly, with a half-emptying time of 1.68 +/- 0.56 h (mean +/- SE). After 24 h, 25.1 +/- 5.2% of the activity remained in the transverse colon. The progression of the geometric center was initially rapid, followed later by a delayed phase. Geometric center reproducibility was found to be high when analyzed using simple linear regression (slope = 0.92; r = 0.73; P less than 0.01). Atropine (0.1 mg/kg im) was found to delay cecum and ascending colon emptying and delay progression of the geometric center. These results demonstrate both 1) the ability of colonic transit scintigraphy to detect changes in transit induced by pharmacological manipulation and 2) the fact that muscarinic blockade inhibits antegrade transit of the fecal stream. We conclude that feline colonic transit may be studied in a quantitative and reproducible manner with colonic transit scintigraphy.

  16. A Root-Colonizing Pseudomonad Lessens Stress Responses in Wheat Imposed by CuO Nanoparticles

    PubMed Central

    Wright, Melanie; Adams, Joshua; Yang, Kwang; McManus, Paul; Jacobson, Astrid; Gade, Aniket; McLean, Joan; Britt, David; Anderson, Anne

    2016-01-01

    Nanoparticle (NPs) containing essential metals are being considered in formulations of fertilizers to boost plant nutrition in soils with low metal bioavailability. This paper addresses whether colonization of wheat roots by the bacterium, Pseudomonas chlororaphis O6 (PcO6), protected roots from the reduced elongation caused by CuO NPs. There was a trend for slightly elongated roots when seedlings with roots colonized by PcO6 were grown with CuO NPs; the density of bacterial cells on the root surface was not altered by the NPs. Accumulations of reactive oxygen species in the plant root cells caused by CuO NPs were little affected by root colonization. However, bacterial colonization did reduce the extent of expression of an array of genes associated with plant responses to stress induced by root exposure to CuO NPs. PcO6 colonization also reduced the levels of two important chelators of Cu ions, citric and malic acids, in the rhizosphere solution; presumably because these acids were used as nutrients for bacterial growth. There was a trend for lower levels of soluble Cu in the rhizosphere solution and reduced Cu loads in the true leaves with PcO6 colonization. These studies indicate that root colonization by bacterial cells modulates plant responses to contact with CuO NPs. PMID:27776146

  17. [Measures to anatomic variations of the colonic vessels in laparoscopic operations].

    PubMed

    Pan, Kai

    2013-10-01

    In laparoscopic colorectal resection, the poor blood supply of the anastomosis after tumor excision is difficult to be determined during the operations sometimes. The change in blood supply of the bowel is mainly due to the mesenteric anatomy and the operative techniques. The direct blood supply of colon is the marginal vessels in the mesentery. The integrity and patency of the marginal vessels determine the vitality of the bowel. However, the marginal vessels are different in diameter, pulsation or even discontinue in various areas, affecting the excision of the colon and following anastomosis. The most common three dangerous areas to anastomosis include:(1)area between ileocolic artery and right colonic artery; (2)area between middle colonic artery and left colonic artery-the Griffiths point. (3)area between the terminal branch of sigmoid colonic artery and superior rectal artery-Sudeck dangerous area. In laparoscopic colorectal resection, one should pay attention to protect the blood supply of the bowel and the marginal blood vessels, and be vigilant to the three vascular variations above mentioned. The vessels should be ligated accurately to ensure sufficient blood supply to the anastomosis and consequent normal healing of the rectal and colonic anastomosis. More attention should be paid to the elderly, morbid, and diabetic patients. If the safety of the anastomosis is unsure, prophylactic ileostomy should be performed. PMID:24158864

  18. Forever competent: deep-sea bivalves are colonized by their chemosynthetic symbionts throughout their lifetime.

    PubMed

    Wentrup, Cecilia; Wendeberg, Annelie; Schimak, Mario; Borowski, Christian; Dubilier, Nicole

    2014-12-01

    Symbiotic bivalves at hydrothermal vents and cold seeps host chemosynthetic bacteria intracellularly in gill cells. In bivalves, the gills grow continuously throughout their lifetime by forming new filaments. We examined how newly developed gill tissues are colonized in bivalves with horizontal and vertical symbiont transmission (Bathymodiolus mussels versus a vesicoymid clam) using fluorescence in situ hybridization and transmission electron microscopy. Symbiont colonization was similar in mussels and clams and was independent of the transmission modes. Symbionts were absent in the growth zones of the gills, indicating that symbionts colonize newly formed gill filaments de novo after they are formed and that gill colonization is a continuous process throughout the host's lifetime. Symbiont abundance and distribution suggested that colonization is shaped by the developmental stage of host cells. Self-infection, in which new gill cells are colonized by symbionts from ontogenetically older gill tissues, may also play a role. In mussels, symbiont infection led to changes in gill cell structure similar to those described from other epithelial cells infected by intracellular pathogens, such as the loss of microvilli. A better understanding of the factors that affect symbiont colonization of bivalve gills could provide new insights into interactions between intracellular bacteria and epithelial tissues.

  19. Identification of bladder and colon afferents in the nodose ganglia of male rats.

    PubMed

    Herrity, April N; Rau, Kristofer K; Petruska, Jeffrey C; Stirling, David P; Hubscher, Charles H

    2014-11-01

    The sensory neurons innervating the urinary bladder and distal colon project to similar regions of the central nervous system and often are affected simultaneously by various diseases and disorders, including spinal cord injury. Anatomical and physiological commonalities between the two organs involve the participation of shared spinally derived pathways, allowing mechanisms of communication between the bladder and colon. Prior electrophysiological data from our laboratory suggest that the bladder also may receive sensory innervation from a nonspinal source through the vagus nerve, which innervates the distal colon as well. The present study therefore aimed to determine whether anatomical evidence exists for vagal innervation of the male rat urinary bladder and to assess whether those vagal afferents also innervate the colon. Additionally, the relative contribution to bladder and colon sensory innervation of spinal and vagal sources was determined. By using lipophilic tracers, neurons that innervated the bladder and colon in both the nodose ganglia (NG) and L6/S1 and L1/L2 dorsal root ganglia (DRG) were quantified. Some single vagal and spinal neurons provided dual innervation to both organs. The proportions of NG afferents labeled from the bladder did not differ from spinal afferents labeled from the bladder when considering the collective population of total neurons from either group. Our results demonstrate evidence for vagal innervation of the bladder and colon and suggest that dichotomizing vagal afferents may provide a neural mechanism for cross-talk between the organs. PMID:24845615

  20. Associations of Probiotics with Vitamin D and Leptin Receptors and their Effects on Colon Cancer.

    PubMed

    Ranji, Peyman; Akbarzadeh, Abolfazl; Rahmati-Yamchi, Mohammad

    2015-01-01

    Colorectal cancer (CRC) is one of most common causes of cancer-related death worldwide. Recent studies have suggested that microbial and environmental factors including diet and lifestyle can impact on colon cancer development. Vitamin D deficiency and dysfunction of vitamin D receptor (VDR) also correlate with colon cancer. Moreover, leptin, a 16-kDa polypeptide, participates in the regulation of food intake and is associated with other environmental factors affecting colon cancer through the leptin receptor. Altered levels of serum leptin and patterns of expression of its receptor (LPR) may be observed in human colon tumours. Furthermore, the collected data from in vitro and in vivo studies have indicated that consuming probiotic non-pathogenic lactic acid bacteria have beneficial effects on colon cancer. Probiotics, inflammation and vitamin D/VDR have been correlated with leptin and its receptor and are also with colon cancer. Thus, in this paper, we review recent progress on the roles of probiotic, vitamin D/VDR and leptin/LPR in inflammation and colon cancer. PMID:25987012

  1. Discordance between peripheral and colonic markers of inflammation during suppressive ART

    PubMed Central

    Dunham, Richard M.; Vujkovic-Cvijin, Ivan; Yukl, Steven A.; Broadhurst, Mara J.; Loke, P’ng; Albright, Rebecca G.; Wong, Joseph K.; Lederman, Michael M.; Somsouk, Ma; Hunt, Peter W.; Martin, Jeffrey N.; Deeks, Steven G.; McCune, Joseph M.

    2014-01-01

    Objective Persistent systemic inflammation is associated with the inability of some HIV-infected patients to normalize circulating CD4+ T-cell levels after years of suppressive antiretroviral therapy (ART). In this work, we sought to understand whether such systemic inflammation is also associated with detectable signs of inflammation in biopsies from the rectosigmoid colon. Design Immunologic and virologic parameters were studied in in the peripheral blood and in rectosigmoid colon biopsies from individuals with viral suppression for at least two years and with peripheral CD4+ T-cell levels <350 cell/mm3 (immunologic nonresponders, n=18) or >500 cell/mm3 (immunologic responders, n=16). Methods Peripheral blood and rectosigmoid colon biopsies were analyzed by flow cytometry, ELISA, and quantitative PCR. Results Non-responders had elevated T-cell activation and inflammatory cytokines in the circulation, but inflammatory gene expression in colon biopsies was not different as compared to responders and there was little relationship between blood and colon markers of inflammation. Blood inflammatory markers were positively associated with sCD14 levels indicative of monocyte activation. Conclusions These findings demonstrate that, in the context of treated HIV disease, it is easier to detect parameters of inflammation (including blood monocyte activation) in the peripheral blood than in isolated rectosigmoid colon biopsies. Accordingly, interventions to block such inflammation in this population might be most conveniently and accurately assessed in blood. PMID:24121758

  2. Milk skimming, heating, acidification, lysozyme, and rennet affect the pattern, repeatability, and predictability of milk coagulation properties and of curd-firming model parameters: A case study of Grana Padano.

    PubMed

    Stocco, G; Cipolat-Gotet, C; Cecchinato, A; Calamari, L; Bittante, G

    2015-08-01

    Milk coagulation properties are used to evaluate the cheesemaking aptitude of milk samples. No international standard procedure exists, although laboratories often mimic the production of a full-fat fresh cheese for milk coagulation properties. Questions have arisen about the predictability of such a procedure for different types of cheese production. The aim of this study was to establish a procedure mimicking the production conditions of a long-ripened hard cheese, taking Protected Designation of Origin Grana Padano as a case study. With respect to the traditional conditions (standard procedure; SP), the Grana Padano procedure (GP) modifications were the use of standardized milk, coagulation lower temperature, previous milk acidification, lysozyme addition, and rennet type. Each modification was tested in turn versus the SP and also all together in the GP. Another 3 tests were carried out: SP on naturally creamed milk, SP with double the quantity of rennet, and a simplified GP on a full-fat milk sample. The 10 procedures were tested on 2 subsamples with 2 replicates each and were repeated using individual milk samples from 15 dual-purpose Simmental cows in 4 sessions for a total of 600 tests. Two Formagraph instruments (Foss Electric A/S, Hillerød, Denmark) measuring curd firmness every 15 s were used, prolonging test duration to 60min to obtain 5 traditional single-point milk coagulation properties and 3 parameters of the curd firming model using all 240 points recorded for each replicate. The 8 traits of each replicate were analyzed according to a mixed model with fixed effects of 4 sessions, 10 treatments, 2 instruments, and 16microvats, and random effects of 15 animals and 300 subsamples. Compared with the SP, the coagulation and curd firming was slowed by low temperature and was accelerated by acidification and by adding a double amount of rennet; natural creaming, fat standardization, and rennet with 5% pepsin affected only some traits, whereas lysozyme

  3. Patch quality and context, but not patch number, drive multi-scale colonization dynamics in experimental aquatic landscapes.

    PubMed

    Resetarits, William J; Binckley, Christopher A

    2013-11-01

    Colonization and extinction are primary drivers of local population dynamics, community structure, and spatial patterns of biological diversity. Existing paradigms of island biogeography, metapopulation biology, and metacommunity ecology, as well as habitat management and conservation biology based on those paradigms, emphasize patch size, number, and isolation as primary characteristics influencing colonization and extinction. Habitat selection theory suggests that patch quality could rival size, number, and isolation in determining rates of colonization and resulting community structure. We used naturally colonized experimental landscapes to address four issues: (a) how do colonizing aquatic beetles respond to variation in patch number, (b) how do they respond to variation in patch quality, (c) does patch context affect colonization dynamics, and (d) at what spatial scales do beetles respond to habitat variation? Increasing patch number had no effect on per patch colonization rates, while patch quality and context were critical in determining colonization rates and resulting patterns of abundance and species richness at multiple spatial scales. We graphically illustrate how variation in immigration rates driven by perceived predation risk (habitat quality) can further modify dynamics of the equilibrium theory of island biogeography beyond predator-driven effects on extinction rates. Our data support the importance of patch quality and context as primary determinants of colonization rate, occupancy, abundance, and resulting patterns of species richness, and reinforce the idea that management of metapopulations for species preservation, and metacommunities for local and regional diversity, should incorporate habitat quality into the predictive equation. PMID:23609801

  4. Patch quality and context, but not patch number, drive multi-scale colonization dynamics in experimental aquatic landscapes.

    PubMed

    Resetarits, William J; Binckley, Christopher A

    2013-11-01

    Colonization and extinction are primary drivers of local population dynamics, community structure, and spatial patterns of biological diversity. Existing paradigms of island biogeography, metapopulation biology, and metacommunity ecology, as well as habitat management and conservation biology based on those paradigms, emphasize patch size, number, and isolation as primary characteristics influencing colonization and extinction. Habitat selection theory suggests that patch quality could rival size, number, and isolation in determining rates of colonization and resulting community structure. We used naturally colonized experimental landscapes to address four issues: (a) how do colonizing aquatic beetles respond to variation in patch number, (b) how do they respond to variation in patch quality, (c) does patch context affect colonization dynamics, and (d) at what spatial scales do beetles respond to habitat variation? Increasing patch number had no effect on per patch colonization rates, while patch quality and context were critical in determining colonization rates and resulting patterns of abundance and species richness at multiple spatial scales. We graphically illustrate how variation in immigration rates driven by perceived predation risk (habitat quality) can further modify dynamics of the equilibrium theory of island biogeography beyond predator-driven effects on extinction rates. Our data support the importance of patch quality and context as primary determinants of colonization rate, occupancy, abundance, and resulting patterns of species richness, and reinforce the idea that management of metapopulations for species preservation, and metacommunities for local and regional diversity, should incorporate habitat quality into the predictive equation.

  5. Contrasting preferences of arbuscular mycorrhizal and dark septate fungi colonizing boreal and subarctic Avenella flexuosa.

    PubMed

    Kauppinen, M; Raveala, K; Wäli, P R; Ruotsalainen, A L

    2014-04-01

    Arbuscular mycorrhizal (AM) and dark septate endophytic (DSE) fungi are ubiquitous in grass roots, but their colonizations may vary according to latitudinal gradient and site conditions. We investigated how vegetation zone (boreal vs. subarctic), humus thickness, and site openness affect root fungal colonizations of the grass Avenella flexuosa. More precisely, we hypothesized that AM and DSE fungal colonizations would have different responses to environmental conditions such that AM fungi could be more common in boreal zone, whereas we expected DSE fungi to be more affected by the amount of humus. We found site openness to affect AM and DSE fungi in a contrasting manner, in interaction with the vegetation zone. AM colonization was high at open coastal dunes, whereas DSE fungi were more common at forested sites, in the boreal zone. Humus thickness affected AM fungi negatively and DSE fungi positively. To conclude, the observed AM and DSE fungal colonization patterns were largely contrasting. AM fungi were favored in seashore conditions characterized by thin humus layer, whereas DSE fungi were favored in conditions of higher humus availability.

  6. Chicken Caecal Microbiome Modifications Induced by Campylobacter jejuni Colonization and by a Non-Antibiotic Feed Additive

    PubMed Central

    Thibodeau, Alexandre; Fravalo, Philippe; Yergeau, Étienne; Arsenault, Julie; Lahaye, Ludovic; Letellier, Ann

    2015-01-01

    Campylobacter jejuni is an important zoonotic foodborne pathogen causing acute gastroenteritis in humans. Chickens are often colonized at very high numbers by C. jejuni, up to 109 CFU per gram of caecal content, with no detrimental effects on their health. Farm control strategies are being developed to lower the C. jejuni contamination of chicken food products in an effort to reduce human campylobacteriosis incidence. It is believed that intestinal microbiome composition may affect gut colonization by such undesirable bacteria but, although the chicken microbiome is being increasingly characterized, information is lacking on the factors affecting its modulation, especially by foodborne pathogens. This study monitored the effects of C. jejuni chicken caecal colonization on the chicken microbiome in healthy chickens. It also evaluated the capacity of a feed additive to affect caecal bacterial populations and to lower C. jejuni colonization. From day-0, chickens received or not a microencapsulated feed additive and were inoculated or not with C. jejuni at 14 days of age. Fresh caecal content was harvested at 35 days of age. The caecal microbiome was characterized by real time quantitative PCR and Ion Torrent sequencing. We observed that the feed additive lowered C. jejuni caecal count by 0.7 log (p<0.05). Alpha-diversity of the caecal microbiome was not affected by C. jejuni colonization or by the feed additive. C. jejuni colonization modified the caecal beta-diversity while the feed additive did not. We observed that C. jejuni colonization was associated with an increase of Bifidobacterium and affected Clostridia and Mollicutes relative abundances. The feed additive was associated with a lower Streptococcus relative abundance. The caecal microbiome remained relatively unchanged despite high C. jejuni colonization. The feed additive was efficient in lowering C. jejuni colonization while not disturbing the caecal microbiome. PMID:26161743

  7. Chicken Caecal Microbiome Modifications Induced by Campylobacter jejuni Colonization and by a Non-Antibiotic Feed Additive.

    PubMed

    Thibodeau, Alexandre; Fravalo, Philippe; Yergeau, Étienne; Arsenault, Julie; Lahaye, Ludovic; Letellier, Ann

    2015-01-01

    Campylobacter jejuni is an important zoonotic foodborne pathogen causing acute gastroenteritis in humans. Chickens are often colonized at very high numbers by C. jejuni, up to 10(9) CFU per gram of caecal content, with no detrimental effects on their health. Farm control strategies are being developed to lower the C. jejuni contamination of chicken food products in an effort to reduce human campylobacteriosis incidence. It is believed that intestinal microbiome composition may affect gut colonization by such undesirable bacteria but, although the chicken microbiome is being increasingly characterized, information is lacking on the factors affecting its modulation, especially by foodborne pathogens. This study monitored the effects of C. jejuni chicken caecal colonization on the chicken microbiome in healthy chickens. It also evaluated the capacity of a feed additive to affect caecal bacterial populations and to lower C. jejuni colonization. From day-0, chickens received or not a microencapsulated feed additive and were inoculated or not with C. jejuni at 14 days of age. Fresh caecal content was harvested at 35 days of age. The caecal microbiome was characterized by real time quantitative PCR and Ion Torrent sequencing. We observed that the feed additive lowered C. jejuni caecal count by 0.7 log (p<0.05). Alpha-diversity of the caecal microbiome was not affected by C. jejuni colonization or by the feed additive. C. jejuni colonization modified the caecal beta-diversity while the feed additive did not. We observed that C. jejuni colonization was associated with an increase of Bifidobacterium and affected Clostridia and Mollicutes relative abundances. The feed additive was associated with a lower Streptococcus relative abundance. The caecal microbiome remained relatively unchanged despite high C. jejuni colonization. The feed additive was efficient in lowering C. jejuni colonization while not disturbing the caecal microbiome. PMID:26161743

  8. Classification of Colon Cancer Patients Based on the Methylation Patterns of Promoters

    PubMed Central

    Choi, Wonyoung; Lee, Jungwoo; Lee, Jin-Young; Lee, Sun-Min; Kim, Da-Won

    2016-01-01

    Diverse somatic mutations have been reported to serve as cancer drivers. Recently, it has also been reported that epigenetic regulation is closely related to cancer development. However, the effect of epigenetic changes on cancer is still elusive. In this study, we analyzed DNA methylation data on colon cancer taken from The Caner Genome Atlas. We found that several promoters were significantly hypermethylated in colon cancer patients. Through clustering analysis of differentially methylated DNA regions, we were able to define subgroups of patients and observed clinical features associated with each subgroup. In addition, we analyzed the functional ontology of aberrantly methylated genes and identified the G-protein-coupled receptor signaling pathway as one of the major pathways affected epigenetically. In conclusion, our analysis shows the possibility of characterizing the clinical features of colon cancer subgroups based on DNA methylation patterns and provides lists of important genes and pathways possibly involved in colon cancer development. PMID:27445647

  9. Genetic Control of Plant Root Colonization by the Biocontrol agent, Pseudomonas fluorescens

    SciTech Connect

    Cole, Benjamin J.; Fletcher, Meghan; Waters, Jordan; Wetmore, Kelly; Blow, Matthew J.; Deutschbauer, Adam M.; Dangl, Jeffry L.; Visel, Axel

    2015-03-19

    Plant growth promoting rhizobacteria (PGPR) are a critical component of plant root ecosystems. PGPR promote plant growth by solubilizing inaccessible minerals, suppressing pathogenic microorganisms in the soil, and directly stimulating growth through hormone synthesis. Pseudomonas fluorescens is a well-established PGPR isolated from wheat roots that can also colonize the root system of the model plant, Arabidopsis thaliana. We have created barcoded transposon insertion mutant libraries suitable for genome-wide transposon-mediated mutagenesis followed by sequencing (TnSeq). These libraries consist of over 105 independent insertions, collectively providing loss-of-function mutants for nearly all genes in the P.fluorescens genome. Each insertion mutant can be unambiguously identified by a randomized 20 nucleotide sequence (barcode) engineered into the transposon sequence. We used these libraries in a gnotobiotic assay to examine the colonization ability of P.fluorescens on A.thaliana roots. Taking advantage of the ability to distinguish individual colonization events using barcode sequences, we assessed the timing and microbial concentration dependence of colonization of the rhizoplane niche. These data provide direct insight into the dynamics of plant root colonization in an in vivo system and define baseline parameters for the systematic identification of the bacterial genes and molecular pathways using TnSeq assays. Having determined parameters that facilitate potential colonization of roots by thousands of independent insertion mutants in a single assay, we are currently establishing a genome-wide functional map of genes required for root colonization in P.fluorescens. Importantly, the approach developed and optimized here for P.fluorescens>A.thaliana colonization will be applicable to a wide range of plant-microbe interactions, including biofuel feedstock plants and microbes known or hypothesized to impact on biofuel-relevant traits including biomass productivity

  10. Dietary guar gum alters colonic microbial fermentation in azoxymethane-treated rats.

    PubMed

    Weaver, G A; Tangel, C; Krause, J A; Alpern, H D; Jenkins, P L; Parfitt, M M; Stragand, J J

    1996-08-01

    To assess the effects of guar gum on colonic microbial fermentation and cancer development, azoxymethane-treated rats were fed a partially hydrolyzed guar or control diet. Anaerobic fecal incubations were conducted at 8-wk intervals, either without added substrate or with cornstarch or hydrolyzed guar as substrates. Short-chain fatty acids in colonic contents and colonic carcinoma areas were measured at 27 wk. Fecal in vitro fermentation rates were higher for guar-fed rats than for control rats [three-way ANOVA (diet, time, in vitro substrates), P = 0.002]. Fecal in vitro butyrate production was greater for guar-fed rats than for control rats after 3-11 weeks of diet treatment (three-way ANOVA, P = 0.027). Butyrate concentrations of colonic contents at 27 wk were higher in guar-fed than in control rats and higher in the cecum than in the post-cecal colon (two-way ANOVA, P = 0.0001). A regression equation predicting colonic carcinoma area (r2 = 0.279) using propionate and butyrate concentrations of the contents of the post-cecal colon showed propionate as a positive predictor (P < 0.001) and butyrate as a negative predictor (P = 0.033). Our results show that patterns of short-chain fatty acid production may affect the results of fiber-carcinogenesis experiments. Dietary addition of hydrolyzed guar is associated with fecal fermentation low in propionate and high in butyrate; short-chain fatty acid concentrations are greater proximally than distally. These results suggest that butyrate protects against colonic neoplasia, whereas propionate enhances it, and demonstrate that colonic microbiota adapt to produce more butyrate if given time and the proper substrate.

  11. [Diffuse ulcerative lesions in the colon with intestinal Behçet's disease].

    PubMed

    Mori, S; Tokutomi, K; Kawamura, H; Takeuchi, A; Hashimoto, T

    1989-06-01

    Ileocecal region is most commonly affected in intestinal Behçet's disease. Localized deep ulcerations which have a punched-out or undermining appearance with well-defined margin placing in this region had been noted in many cases. 41 patients with intestinal Behçet's disease were observed by colonofiberscope in Teikyo University Hospital from January 1982 to June 1988. In 10% (4 cases) of these patients, diffuse ulcerative lesions in the transverse colon and the distal colon were found. These diffuse lesions in the colon with Behçet's disease were seemed to be much like those associated with inflammatory bowel disease as ulcerative colitis and Crohn's disease in morphological characteristics. The clinical symptoms of these four cases with Behçet's disease including oral aphtha, genital ulcer, joint pain, skin eruptions, and eye involvement, preceded each colonic ulceration. The first two cases were affected with ulcerative lesion in the distal portion of the recto-sigmoid colon and the descending colon. And the last two were involved in the whole transversing colon by multiple deep ulcerations. Wide-spreading ulcerative lesion in the colon with Behçet's disease is a rare condition in the Japanese, and only two papers has been reported previously. Because clinical manifestations between Behçet's disease and inflammatory bowel disease are very similar in many points as oral aphthous ulcers, arthritis, eye involvement, skin eruptions, phlebitis, arterial occlusions, then, an overlapping field or a part of a spectrum of disease has been suggested by some authors. But, in the present circumstances, they are distinct disease entities, we think that these four cases are in an atypical condition with intestinal Behçet's disease. PMID:2814706

  12. [The intraoperative colonic irrigation in emergency surgery].

    PubMed

    Kiss, L

    2001-01-01

    Bowel preparations is frequently impossible in various ante colonic diseases, such as left-sided colonic obstruction. The goal of intraoperative colonic irrigation is to obtain, during surgery, a bowel preparation offering the possibility of primary resection with immediate anastomosis, when preoperative bowel preparation has not been feasible. Technical aspects of intra-operative colonic irrigation are described. Indications for this methods are presented: left-sided obstructing carcinomas, diverticulitis, more rarely inflammatory stenosis or functional obstruction. The surgical management of left colonic emergencies has evolved in the past few decades. Recently, there has been increasing interest in resection with primary anastomosis in selected cases. The post operative mortality rate was 13 per cent. The incidence of clinical anastomotic leakage was 6.65 per cent. PMID:12731192

  13. Interaction between plants and bacteria: glucosinolates and phyllospheric colonization of cruciferous vegetables by Enterobacter radicincitans DSM 16656.

    PubMed

    Schreiner, Monika; Krumbein, Angelika; Ruppel, Silke

    2009-01-01

    For determining interactive plant-bacterial effects between glucosinolates and phyllospheric colonization by a plant growth-promoting strain, Enterobacter radicincitans DSM 16656, in cruciferous vegetables, the extent of bacterial colonization was assessed in 5 cruciferous vegetables (Brassica juncea, Brassica campestris, Brassica oleracea var. capitata, Brassica rapa var. alboglabra, Nasturtium officinale) using a species-specific TaqMan probe and quantitative real-time PCR. Colonization ability of inoculated E. radicincitans in the phyllosphere of these species varied from inability to colonize B. rapa up to a very good colonization rate of B. campestris. In addition to morphological factors and other plant compounds, the colonization rate was affected by different individual aromatic and aliphatic glucosinolates and their concentration, revealing that both plant pathogens and plant growth-promoting bacteria were affected by glucosinolates in their colonization behavior. In contrast, after E. radicincitans inoculation neither the total nor the individual glucosinolate concentrations in the phyllosphere of the 5 cruciferous species were affected, indicating that the nonpathogenic E. radicincitans might cause only poor cell damage by metabolizing plant cell components and does not induce a plant defense response and thus subsequently an increased glucosinolate concentration in the phyllosphere. Moreover, E. radicincitans induced no stimulation of indole glucosinolate biosynthesis by additional bacterial auxin supply.

  14. Interaction between plants and bacteria: glucosinolates and phyllospheric colonization of cruciferous vegetables by Enterobacter radicincitans DSM 16656.

    PubMed

    Schreiner, Monika; Krumbein, Angelika; Ruppel, Silke

    2009-01-01

    For determining interactive plant-bacterial effects between glucosinolates and phyllospheric colonization by a plant growth-promoting strain, Enterobacter radicincitans DSM 16656, in cruciferous vegetables, the extent of bacterial colonization was assessed in 5 cruciferous vegetables (Brassica juncea, Brassica campestris, Brassica oleracea var. capitata, Brassica rapa var. alboglabra, Nasturtium officinale) using a species-specific TaqMan probe and quantitative real-time PCR. Colonization ability of inoculated E. radicincitans in the phyllosphere of these species varied from inability to colonize B. rapa up to a very good colonization rate of B. campestris. In addition to morphological factors and other plant compounds, the colonization rate was affected by different individual aromatic and aliphatic glucosinolates and their concentration, revealing that both plant pathogens and plant growth-promoting bacteria were affected by glucosinolates in their colonization behavior. In contrast, after E. radicincitans inoculation neither the total nor the individual glucosinolate concentrations in the phyllosphere of the 5 cruciferous species were affected, indicating that the nonpathogenic E. radicincitans might cause only poor cell damage by metabolizing plant cell components and does not induce a plant defense response and thus subsequently an increased glucosinolate concentration in the phyllosphere. Moreover, E. radicincitans induced no stimulation of indole glucosinolate biosynthesis by additional bacterial auxin supply. PMID:19556746

  15. "Cat scratch colon" in a patient with ischemic colitis.

    PubMed

    Park, Eui Ju; Lee, Joon Seong; Lee, Tae Hee; Choi, Dae Han; Kim, Eui Bae; Jeon, Seong Ran; Hong, Su Jin; Kim, Jin-Oh

    2015-03-01

    "Cat scratch colon" is a gross finding characterized by hemorrhagic mucosal scratches on colonoscopy. It is usually associated with a normal colon and is rarely associated with collagenous colitis. In a previous report, cat scratch colon was noted in the cecum and ascending colon, but has also been observed in the distal transverse colon. The patient in this study was also diagnosed with ischemic colitis that may have played a role in the development of cat scratch colon.

  16. Calcite Precipitation at an Arctic Geothermal Spring Leads to Endolith Colonization and Ecological Succession

    NASA Astrophysics Data System (ADS)

    Starke, V.; Fogel, M. L.; Steele, A.

    2012-12-01

    A critical question in microbial ecology concerns how environmental conditions affect community makeup. Troll Springs, a geothermal spring at 79°23'N, 13°26'E on Svalbard in the high Arctic, provides an opportunity to study microbial communities and succession along steep environmental gradients that impose strong selective pressures. At Troll, warm water is released into cold, dry climate conditions. Precipitation of calcite from the spring's waters has built terraces that host a range of microbial communities. Microorganisms exist in warm water as periphyton, in moist granular materials, and in cold, dry rock as endoliths. Troll therefore has two distinct ecosystems, aquatic and terrestrial, in close proximity, with different underlying environmental factors shaping their microbial communities. We use microscopic and phylogeny-based molecular methods to study microbial community makeup at Troll Springs. Periphyton are entrapped by precipitation of calcite, becoming precursors for endolithic communities. Much of the pore space originally occupied by periphyton becomes inhabited either by organisms that were already present in minor quantities in the periphyton, or by new organisms that colonized an environment for which they were well suited. This process differs from most endolith colonization, where rock predates the communities that colonize it. In the aquatic environments, the strongest dependence of community makeup is on pH and temperature, with gradual changes in community makeup along a pH/temperature gradient among the pools. Illumination (as limited by calcite precipitation) and thermal stability also appear to exert influence. In contrast, in the granular and endolithic terrestrial environments, where water is scarce and therefore exerts selective pressure, there is a strong relationship between community makeup and water content. The richness, evenness, and diversity of microbial taxa are all strongly correlated at Troll Springs. These parameters all

  17. Influence of soil organic matter decomposition on arbuscular mycorrhizal fungi in terms of asymbiotic hyphal growth and root colonization.

    PubMed

    Gryndler, Milan; Hrselová, Hana; Cajthaml, Tomás; Havránková, Marie; Rezácová, Veronika; Gryndlerová, Hana; Larsen, John

    2009-04-01

    Soil organic matter is known to influence arbuscular mycorrhizal (AM) fungi, but limited information is available on the chemical components in the organic matter causing these effects. We studied the influence of decomposing organic matter (pure cellulose and alfalfa shoot and root material) on AM fungi after 30, 100, and 300 days of decomposition in nonsterile soil with and without addition of mineral N and P. Decomposing organic matter affected maize root length colonized by the AM fungus Glomus claroideum in a similar manner as other plant growth parameters. Colonized root length was slightly increased by both nitrogen and phosphorus application and plant materials, but not by application of cellulose. In vitro hyphal growth of Glomus intraradices was increased by soil extracts from the treatments with all types of organic materials independently of mineral N and P application. Pyrolysis of soil samples from the different decomposition treatments revealed in total 266 recognizable organic compounds and in vitro hyphal growth of G. intraradices in soil extract positively correlated with 33 of these compounds. The strongest correlation was found with 3,4,5-trimethoxybenzoic acid methyl ester. This compound is a typical product of pyrolysis of phenolic compounds produced by angiosperm woody plants, but in our experiment, it was produced mainly from cellulose by some components of the soil microflora. In conclusion, our results indicate that mycelia of AM fungi are influenced by organic matter decomposition both via compounds released during the decomposition process and also by secondary metabolites produced by microorganisms involved in organic matter decomposition.

  18. Effects of a Mediterranean Diet Intervention on Anti- and Pro-Inflammatory Eicosanoids, Epithelial Proliferation, and Nuclear Morphology in Biopsies of Normal Colon Tissue.

    PubMed

    Djuric, Zora; Turgeon, D Kim; Ren, Jianwei; Neilson, Andrew; Plegue, Missy; Waters, Ian G; Chan, Alexander; Askew, Leah M; Ruffin, Mack T; Sen, Ananda; Brenner, Dean E

    2015-01-01

    This randomized trial evaluated the effects of intervention with either a Healthy Eating or a Mediterranean diet on colon biomarkers in 120 healthy individuals at increased colon cancer risk. The hypothesis was that eicosanoids and markers of proliferation would be favorably affected by the Mediterranean diet. Colon epithelial biopsy tissues and blood samples were obtained at baseline and after 6 mo of intervention. Colonic eicosanoid concentrations were evaluated by HPLC-MS-MS, and measures of epithelial proliferation and nuclear morphology were evaluated by image analysis of biopsy sections. There was little change in proinflammatory eicosanoids and in plasma cytokine concentrations with either dietary intervention. There was, however, a 50% increase in colonic prostaglandin E3 (PGE3), which is formed from eicosapentanoic acid, in the Mediterranean arm. Unlike PGE2, PGE3, was not significantly affected by regular use of non-steroidal anti-inflammatory drugs at baseline, and normal weight subjects had significantly higher colon PGE3 than overweight or obese subjects. Increased proliferation in the colon at baseline, by Ki67 labeling, was associated with morphological features that defined smaller nuclei in the epithelial cells, lower colon leukotriene concentrations and higher plasma cytokine concentrations. Dietary intervention had little effect on measures of epithelial proliferation or of nuclear morphology. The increase in PGE3 with a Mediterranean diet indicates that in normal colon, diet might affect protective pathways to a greater extent than proinflammatory and proliferative pathways. Hence, biomarkers from cancer models might not be relevant in a true prevention setting.

  19. Differences in AM fungal root colonization between populations of perennial Aster species have genetic reasons.

    PubMed

    Pánková, Hana; Münzbergová, Zuzana; Rydlová, Jana; Vosátka, Miroslav

    2008-08-01

    We tested the hypothesis whether differences between plant populations in root colonization by arbuscular mycorrhizal (AM) fungi could be caused by genetic differentiation between populations. In addition, we investigated whether the response to AM fungi differs between plants from different populations and if it is affected by the soil in which the plants are cultivated. We used Aster amellus, which occurs in fragmented dry grasslands, as a model species and we studied six different populations from two regions, which varied in soil nutrient concentration. We found significant differences in the degree of mycorrhizal colonization of plant roots between regions in the field. To test if these differences were due to phenotypic plasticity or had a genetic basis, we performed a greenhouse experiment. The results suggested that Aster amellus is an obligate mycotrophic plant species with a high dependency upon mycorrhiza. Plant biomass was affected only by soil, and not by population or the interaction between the population and the soil. Mycorrhizal colonization was significantly affected by all three factors (soil, population, interaction of soil and population). Plants from the population originating from the soil with lower nutrient availability developed more mycorrhiza even when grown in soil with higher nutrient availability. The correspondence between mycorrhizal colonization of plants in the field and in both soils in the pot experiment suggests that the observed differences in root colonization have a genetic basis.

  20. Analysis of the depolarizing properties of normal and adenomatous polyps in colon mucosa for the early diagnosis of precancerous lesions

    NASA Astrophysics Data System (ADS)

    Ortega-Quijano, Noé; Fanjul-Vélez, Félix; de Cos-Pérez, Jesús; Arce-Diego, José Luis

    2011-09-01

    Optical characterization of biological tissues by means of polarimetric techniques is an area of growing interest. Polarized light can be used for malignant neoplasms detection. To our knowledge, few studies have so far focused on lesions that are prone to result in cancer. In this work we present a polarimetric study of depolarization in prepathological tissues. Specifically, we will focus on premalignant lesions in human colon due to their clinical relevance. Colonic adenoma, the potential precursor of malignant adenocarcinoma, provokes significant structural modifications in colon mucosa that affect light depolarization. The depolarizing properties of normal and adenomatous polyps mucosa are compared. The average linear degree of polarization is shown to present a strong dependence with the precancerous state of the colonic tissue. This method has the potential to enable an early diagnosis of colon cancer.

  1. Colonic mucin synthesis is increased by sodium butyrate.

    PubMed

    Finnie, I A; Dwarakanath, A D; Taylor, B A; Rhodes, J M

    1995-01-01

    The effects of sodium butyrate and sodium bromo-octanoate (an inhibitor of beta oxidation) on colonic mucus glycoprotein (mucin) synthesis have been assessed using tissue from colonic resection samples. Epithelial biopsy specimens were incubated for 16 hours in RPMI 1640 with glutamine, supplemented with 10% fetal calf serum and N-acetyl-[3H]-glucosamine ([3H]-Glc NAc), and differing concentrations of sodium butyrate. Incorporation of [3H] Glc NAc into mucin by normal epithelium at least 10 cm distant from colonic cancer was increased in the presence of sodium butyrate in a dose dependent manner, with maximum effect (476%) at a concentration of 0.1 mM (number of specimens = 24 from six patients, p < 0.001). The increase in response to butyrate was not seen when specimens were incubated in the presence of the beta oxidation inhibitor sodium bromo-octanoate 0.05 M. The striking increase in mucin synthesis that results when butyrate is added to standard nutrient medium suggests that this may be an important mechanism affecting the rate of mucin synthesis in vivo and may also explain the therapeutic effect of butyrate in colitis. PMID:7890244

  2. Human colon-derived soluble factors modulate gut microbiota composition.

    PubMed

    Hevia, Arancha; Bernardo, David; Montalvillo, Enrique; Al-Hassi, Hafid O; Fernández-Salazar, Luis; Garrote, Jose A; Milani, Christian; Ventura, Marco; Arranz, Eduardo; Knight, Stella C; Margolles, Abelardo; Sánchez, Borja

    2015-01-01

    The commensal microbiota modulates immunological and metabolic aspects of the intestinal mucosa contributing to development of human gut diseases including inflammatory bowel disease. The host/microbiota interaction often referred to as a crosstalk, mainly focuses on the effect of the microbiota on the host neglecting effects that the host could elicit on the commensals. Colonic microenvironments from three human healthy controls (obtained from the proximal and distal colon, both in resting conditions and after immune - IL-15- and microbiota - LPS-in vitro challenges) were used to condition a stable fecal population. Subsequent 16S rRNA gene-based analyses were performed to study the effect induced by the host on the microbiota composition and function. Non-supervised principal component analysis (PCA) showed that all microbiotas, which had been conditioned with colonic microenvironments clustered together in terms of relative microbial composition, suggesting that soluble factors were modulating a stable fecal population independently from the treatment or the origin. Our findings confirmed that the host intestinal microenvironment has the capacity to modulate the gut microbiota composition via yet unidentified soluble factors. These findings indicate that an appropriate understanding of the factors of the host mucosal microenvironment affecting microbiota composition and function could improve therapeutic manipulation of the microbiota composition. PMID:25918688

  3. Colonic mucin synthesis is increased by sodium butyrate.

    PubMed

    Finnie, I A; Dwarakanath, A D; Taylor, B A; Rhodes, J M

    1995-01-01

    The effects of sodium butyrate and sodium bromo-octanoate (an inhibitor of beta oxidation) on colonic mucus glycoprotein (mucin) synthesis have been assessed using tissue from colonic resection samples. Epithelial biopsy specimens were incubated for 16 hours in RPMI 1640 with glutamine, supplemented with 10% fetal calf serum and N-acetyl-[3H]-glucosamine ([3H]-Glc NAc), and differing concentrations of sodium butyrate. Incorporation of [3H] Glc NAc into mucin by normal epithelium at least 10 cm distant from colonic cancer was increased in the presence of sodium butyrate in a dose dependent manner, with maximum effect (476%) at a concentration of 0.1 mM (number of specimens = 24 from six patients, p < 0.001). The increase in response to butyrate was not seen when specimens were incubated in the presence of the beta oxidation inhibitor sodium bromo-octanoate 0.05 M. The striking increase in mucin synthesis that results when butyrate is added to standard nutrient medium suggests that this may be an important mechanism affecting the rate of mucin synthesis in vivo and may also explain the therapeutic effect of butyrate in colitis.

  4. Human Colon-Derived Soluble Factors Modulate Gut Microbiota Composition

    PubMed Central

    Hevia, Arancha; Bernardo, David; Montalvillo, Enrique; Al-Hassi, Hafid O.; Fernández-Salazar, Luis; Garrote, Jose A.; Milani, Christian; Ventura, Marco; Arranz, Eduardo; Knight, Stella C.; Margolles, Abelardo; Sánchez, Borja

    2015-01-01

    The commensal microbiota modulates immunological and metabolic aspects of the intestinal mucosa contributing to development of human gut diseases including inflammatory bowel disease. The host/microbiota interaction often referred to as a crosstalk, mainly focuses on the effect of the microbiota on the host neglecting effects that the host could elicit on the commensals. Colonic microenvironments from three human healthy controls (obtained from the proximal and distal colon, both in resting conditions and after immune – IL-15- and microbiota – LPS-in vitro challenges) were used to condition a stable fecal population. Subsequent 16S rRNA gene-based analyses were performed to study the effect induced by the host on the microbiota composition and function. Non-supervised principal component analysis (PCA) showed that all microbiotas, which had been conditioned with colonic microenvironments clustered together in terms of relative microbial composition, suggesting that soluble factors were modulating a stable fecal population independently from the treatment or the origin. Our findings confirmed that the host intestinal microenvironment has the capacity to modulate the gut microbiota composition via yet unidentified soluble factors. These findings indicate that an appropriate understanding of the factors of the host mucosal microenvironment affecting microbiota composition and function could improve therapeutic manipulation of the microbiota composition. PMID:25918688

  5. Human colon-derived soluble factors modulate gut microbiota composition.

    PubMed

    Hevia, Arancha; Bernardo, David; Montalvillo, Enrique; Al-Hassi, Hafid O; Fernández-Salazar, Luis; Garrote, Jose A; Milani, Christian; Ventura, Marco; Arranz, Eduardo; Knight, Stella C; Margolles, Abelardo; Sánchez, Borja

    2015-01-01

    The commensal microbiota modulates immunological and metabolic aspects of the intestinal mucosa contributing to development of human gut diseases including inflammatory bowel disease. The host/microbiota interaction often referred to as a crosstalk, mainly focuses on the effect of the microbiota on the host neglecting effects that the host could elicit on the commensals. Colonic microenvironments from three human healthy controls (obtained from the proximal and distal colon, both in resting conditions and after immune - IL-15- and microbiota - LPS-in vitro challenges) were used to condition a stable fecal population. Subsequent 16S rRNA gene-based analyses were performed to study the effect induced by the host on the microbiota composition and function. Non-supervised principal component analysis (PCA) showed that all microbiotas, which had been conditioned with colonic microenvironments clustered together in terms of relative microbial composition, suggesting that soluble factors were modulating a stable fecal population independently from the treatment or the origin. Our findings confirmed that the host intestinal microenvironment has the capacity to modulate the gut microbiota composition via yet unidentified soluble factors. These findings indicate that an appropriate understanding of the factors of the host mucosal microenvironment affecting microbiota composition and function could improve therapeutic manipulation of the microbiota composition.

  6. Colonization dynamics of ciliate morphotypes modified by shifting sandy sediments.

    PubMed

    Risse-Buhl, Ute; Felsmann, Katja; Mutz, Michael

    2014-08-01

    Sandy stream-bed sediments colonized by a diverse ciliate community are subject to various disturbance regimes. In microcosms, we investigated the effect of sediment shifting on the colonization dynamics of 3 ciliate morphotypes differing in morphology, behavior and feeding strategy. The dynamics of the ciliate morphotypes inhabiting sediment pore water and overlying water were observed at 3 sediment shifting frequencies: (1) stable sediments, (2) periodically shifting sediments such as migrating ripples, and (3) continuously shifting sediments as occurring during scour events of the uppermost sediment. Sediment shifting significantly affected the abundance and growth rate of the ciliate morphotypes. The free-swimming filter feeder Dexiostoma campylum was vulnerable to washout by sediment shifting since significantly higher numbers occurred in the overlying water than in pore water. Abundance of D. campylum only increased in pore water of stable sediments. On the contrary, the vagile grasper feeder Chilodonella uncinata and the sessile filter feeder Vorticella convallaria had positive growth rates and successfully colonized sediments that shifted periodically and continuously. Thus, the spatio-temporal pattern of sediment dynamics acts as an essential factor of impact on the structure, distribution and function of ciliate communities in sand-bed streams.

  7. Fermented dairy products modulate Citrobacter rodentium-induced colonic hyperplasia.

    PubMed

    Collins, James W; Chervaux, Christian; Raymond, Benoit; Derrien, Muriel; Brazeilles, Rémi; Kosta, Artemis; Chambaud, Isabelle; Crepin, Valerie F; Frankel, Gad

    2014-10-01

    We evaluated the protective effects of fermented dairy products (FDPs) in an infection model, using the mouse pathogen Citrobacter rodentium (CR). Treatment of mice with FDP formulas A, B, and C or a control product did not affect CR colonization, organ specificity, or attaching and effacing lesion formation. Fermented dairy product A (FDP-A), but neither the supernatant from FDP-A nor β-irradiated (IR) FDP-A, caused a significant reduction in colonic crypt hyperplasia and CR-associated pathology. Profiling the gut microbiota revealed that IR-FDP-A promoted higher levels of phylotypes belonging to Alcaligenaceae and a decrease in Lachnospiraceae (Ruminococcus) during CR infection. Conversely, FDP-A prevented a decrease in Ruminococcus and increased Turicibacteraceae (Turicibacter). Importantly, loss of Ruminococcus and Turicibacter has been associated with susceptibility to dextran sodium sulfate-induced colitis. Our results demonstrate that viable bacteria in FDP-A reduced CR-induced colonic crypt hyperplasia and prevented the loss of key bacterial genera that may contribute to disease pathology.

  8. Automated image-based colon cleansing for laxative-free CT colonography computer-aided polyp detection

    SciTech Connect

    Linguraru, Marius George; Panjwani, Neil; Fletcher, Joel G.; Summer, Ronald M.

    2011-12-15

    Purpose: To evaluate the performance of a computer-aided detection (CAD) system for detecting colonic polyps at noncathartic computed tomography colonography (CTC) in conjunction with an automated image-based colon cleansing algorithm. Methods: An automated colon cleansing algorithm was designed to detect and subtract tagged-stool, accounting for heterogeneity and poor tagging, to be used in conjunction with a colon CAD system. The method is locally adaptive and combines intensity, shape, and texture analysis with probabilistic optimization. CTC data from cathartic-free bowel preparation were acquired for testing and training the parameters. Patients underwent various colonic preparations with barium or Gastroview in divided doses over 48 h before scanning. No laxatives were administered and no dietary modifications were required. Cases were selected from a polyp-enriched cohort and included scans in which at least 90% of the solid stool was visually estimated to be tagged and each colonic segment was distended in either the prone or supine view. The CAD system was run comparatively with and without the stool subtraction algorithm. Results: The dataset comprised 38 CTC scans from prone and/or supine scans of 19 patients containing 44 polyps larger than 10 mm (22 unique polyps, if matched between prone and supine scans). The results are robust on fine details around folds, thin-stool linings on the colonic wall, near polyps and in large fluid/stool pools. The sensitivity of the CAD system is 70.5% per polyp at a rate of 5.75 false positives/scan without using the stool subtraction module. This detection improved significantly (p = 0.009) after automated colon cleansing on cathartic-free data to 86.4% true positive rate at 5.75 false positives/scan. Conclusions: An automated image-based colon cleansing algorithm designed to overcome the challenges of the noncathartic colon significantly improves the sensitivity of colon CAD by approximately 15%.

  9. Reversible Projection Technique for Colon Unfolding

    PubMed Central

    Yao, Jianhua; Chowdhury, Ananda S.; Aman, Javed; Summers, Ronald M.

    2015-01-01

    Colon unfolding provides an efficient way to navigate the colon in CT colonography. Most existing unfolding techniques only computed forward projections. When radiologists find abnormalities or conduct measurements on the unfolded view (which is often quicker and easier), it is difficult to locate the corresponding region on the 3D view for further examination (which is more accurate and reliable). To address this, we propose a reversible projection technique for colon unfolding. The method makes use of advanced algorithms including rotation-minimizing frames, recursive ring sets, mesh skinning and cylindrical projection. Both forward and reverse transformations are computed for points on the colon surface. Therefore, it allows for detecting and measuring polyps on the unfolded view and mapping them back to the 3D surface. We generated realistic colon simulation incorporating most colon characteristics such as curved centerline, variable distention, haustral folds, teniae coli and colonic polyps. Our method was tested on both the simulated data and 110 clinical CT colonography data. Comparison of polyp size measurements on the unfolded view and the 3D view clearly demonstrates the importance of our reversible projection technique. PMID:20542756

  10. Clinical impact of Clostridium difficile colonization.

    PubMed

    Hung, Yuan-Pin; Lee, Jen-Chieh; Lin, Hsiao-Ju; Liu, Hsiao-Chieh; Wu, Yi-Hui; Tsai, Pei-Jane; Ko, Wen-Chien

    2015-06-01

    Clostridium difficile can cause antibiotic-associated diarrhea in hospitalized patients. Asymptomatic colonization by C. difficile is common during the neonatal period and early infancy, ranging from 21% to 48%, and in childhood. The colonization rate of C. difficile in adult hospitalized patients shows geographic variation, ranging from 4.4% to 23.2%. Asymptomatic carriage in neonates caused no further disease in many studies, whereas adult patients colonized with toxigenic C. difficile were prone to the subsequent development of C. difficile-associated diarrhea (CDAD). However, the carriage of nontoxigenic C. difficile strains appears to prevent CDAD in hamsters and humans. Risk factors for C. difficile colonization include recent hospitalization, exposure to antimicrobial agents or gastric acid-suppressing drugs (such as proton-pump inhibitors and H2 blockers), a history of CDAD or cytomegalovirus infection, the presence of an underlying illness, receipt of immunosuppressants, the presence of antibodies against toxin B, and Toll-like receptor 4 polymorphisms. Asymptomatic C. difficile carriers are associated with significant skin and environmental contamination, similar to those with CDAD, and contact isolation and hand-washing practices should therefore be employed as infection control policies for the prevention of C. difficile spread. Treating patients with asymptomatic C. difficile colonization with metronidazole or vancomycin is not suggested by the currently available evidence. In conclusion, asymptomatic C. difficile colonization may lead to skin and environmental contamination by C. difficile, but more attention should be paid to the clinical impact of those with C. difficile colonization.

  11. Innate lymphoid cells sustain colon cancer through production of interleukin-22 in a mouse model.

    PubMed

    Kirchberger, Stefanie; Royston, Daniel J; Boulard, Olivier; Thornton, Emily; Franchini, Fanny; Szabady, Rose L; Harrison, Oliver; Powrie, Fiona

    2013-05-01

    Patients with inflammatory bowel disease (IBD) have an increased risk of colon cancer. However, the immune cells and cytokines that mediate the transition from intestinal inflammation to cancer are poorly understood. We show that bacteria-induced colon cancer is accompanied by differential accumulation of IL-17(+)IL-22(+) colonic innate lymphoid cells (cILCs), which are phenotypically distinct from LTi and NK-22 cells, and that their depletion in mice with dysplastic inflammation blocks the development of invasive colon cancer. Analysis of the functional role of distinct Type 17 cytokines shows that although blockade of IL-17 inhibits some parameters of intestinal inflammation, reduction in dysplasia and colorectal cancer (CRC) requires neutralization of IL-22 indicating a unique role for IL-22 in the maintenance of cancer in this model. Mechanistic analyses showed that IL-22 selectively acts on epithelial cells to induce Stat3 phosphorylation and proliferation. Importantly, we could detect IL-22(+)CD3(+) and IL-22(+)CD3(−) cells in human CRC. Our results describe a new activity of IL-22 in the colon as a nonredundant mediator of the inflammatory cascade required for perpetuation of CRC, highlighting the IL-22 axis as a novel therapeutic target in colon cancer.

  12. Circadian regulation of electrolyte absorption in the rat colon.

    PubMed

    Soták, M; Polidarová, L; Musílková, J; Hock, M; Sumová, A; Pácha, J

    2011-12-01

    The intestinal transport of nutrients exhibits distinct diurnal rhythmicity, and the enterocytes harbor a circadian clock. However, temporal regulation of the genes involved in colonic ion transport, i.e., ion transporters and channels operating in absorption and secretion, remains poorly understood. To address this issue, we assessed the 24-h profiles of expression of genes encoding the sodium pump (subunits Atp1a1 and Atp1b1), channels (α-, β-, and γ-subunits of Enac and Cftr), transporters (Dra, Ae1, Nkcc1, Kcc1, and Nhe3), and the Na(+)/H(+) exchanger (NHE) regulatory factor (Nherf1) in rat colonic mucosa. Furthermore, we investigated temporal changes in the spatial localization of the clock genes Per1, Per2, and Bmal1 and the genes encoding ion transporters and channels along the crypt axis. In rats fed ad libitum, the expression of Atp1a1, γEnac, Dra, Ae1, Nhe3, and Nherf1 showed circadian variation with maximal expression at circadian time 12, i.e., at the beginning of the subjective night. The peak γEnac expression coincided with the rise in plasma aldosterone. Restricted feeding phase advanced the expression of Dra, Ae1, Nherf, and γEnac and decreased expression of Atp1a1. The genes Atp1b1, Cftr, αEnac, βEnac, Nkcc1, and Kcc1 did not show any diurnal variations in mRNA levels. A low-salt diet upregulated the expression of βEnac and γEnac during the subjective night but did not affect expression of αEnac. Similarly, colonic electrogenic Na(+) transport was much higher during the subjective night than the subjective day. These findings indicate that the transporters and channels operating in NaCl absorption undergo diurnal regulation and suggest a role of an intestinal clock in the coordination of colonic NaCl absorption.

  13. Size matters: nest colonization patterns for twig-nesting ants.

    PubMed

    Jiménez-Soto, Estelí; Philpott, Stacy M

    2015-08-01

    Understanding the drivers of ant diversity and co-occurrence in agroecosystems is fundamental because ants participate in interactions that influence agroecosystem processes. Multiple local and regional factors influence ant community assembly.We examined local factors that influence the structure of a twig-nesting ant community in a coffee system in Mexico using an experimental approach. We investigated whether twig characteristics (nest entrance size and diversity of nest entrance sizes) and nest strata (canopy shade tree or coffee shrub) affected occupation, species richness, and community composition of twig-nesting ants and whether frequency of occupation of ant species varied with particular nest entrance sizes or strata.We conducted our study in a shaded coffee farm in Chiapas, Mexico, between March and June 2012. We studied ant nest colonization by placing artificial nests (bamboo twigs) on coffee shrubs and shade trees either in diverse or uniform treatments. We also examined whether differences in vegetation (no. of trees, canopy cover and coffee density) influenced nest colonization.We found 33 ant species occupying 73% of nests placed. Nest colonization did not differ with nest strata or size. Mean species richness of colonizing ants was significantly higher in the diverse nest size entrance treatment, but did not differ with nest strata. Community composition differed between strata and also between the diverse and uniform size treatments on coffee shrubs, but not on shade trees. Some individual ant species were more frequently found in certain nest strata and in nests with certain entrance sizes.Our results indicate that twig-nesting ants are nest-site limited, quickly occupy artificial nests of many sizes, and that trees or shrubs with twigs of a diversity of entrance sizes likely support higher ant species richness. Further, individual ant species more frequently occupy nests with different sized entrances promoting ant richness on individual coffee

  14. Size matters: nest colonization patterns for twig-nesting ants

    PubMed Central

    Jiménez-Soto, Estelí; Philpott, Stacy M

    2015-01-01

    Understanding the drivers of ant diversity and co-occurrence in agroecosystems is fundamental because ants participate in interactions that influence agroecosystem processes. Multiple local and regional factors influence ant community assembly. We examined local factors that influence the structure of a twig-nesting ant community in a coffee system in Mexico using an experimental approach. We investigated whether twig characteristics (nest entrance size and diversity of nest entrance sizes) and nest strata (canopy shade tree or coffee shrub) affected occupation, species richness, and community composition of twig-nesting ants and whether frequency of occupation of ant species varied with particular nest entrance sizes or strata. We conducted our study in a shaded coffee farm in Chiapas, Mexico, between March and June 2012. We studied ant nest colonization by placing artificial nests (bamboo twigs) on coffee shrubs and shade trees either in diverse or uniform treatments. We also examined whether differences in vegetation (no. of trees, canopy cover and coffee density) influenced nest colonization. We found 33 ant species occupying 73% of nests placed. Nest colonization did not differ with nest strata or size. Mean species richness of colonizing ants was significantly higher in the diverse nest size entrance treatment, but did not differ with nest strata. Community composition differed between strata and also between the diverse and uniform size treatments on coffee shrubs, but not on shade trees. Some individual ant species were more frequently found in certain nest strata and in nests with certain entrance sizes. Our results indicate that twig-nesting ants are nest-site limited, quickly occupy artificial nests of many sizes, and that trees or shrubs with twigs of a diversity of entrance sizes likely support higher ant species richness. Further, individual ant species more frequently occupy nests with different sized entrances promoting ant richness on individual

  15. Community assembly in epiphytic lichens in early stages of colonization.

    PubMed

    Gjerde, Ivar; Blom, Hans H; Lindblom, Louise; Saetersdal, Magne; Schei, Fride Høstad

    2012-04-01

    Colonization studies may function as natural experiments and have the potential of addressing important questions about community assembly. We studied colonization for a guild of epiphytic lichens in a former treeless heathland area of 170 km2 in southwest Norway. We investigated if epiphytic lichen species richness and composition on aspen (Populus tremula) trees corresponded to a random draw of lichen individuals from the regional species pool. We compared lichen communities of isolated young (55-120 yr) and old (140-200 yr) forest patches in the heathland area to those of aspen forest in an adjacent reference area that has been forested for a long time. All thalli (lichen bodies) of 32 selected lichen species on trunks of aspen were recorded in 35 aspen sites. When data for each site category (young, old, and reference) were pooled, we found the species richness by rarefaction to be similar for reference sites and old sites, but significantly lower for young sites. The depauperated species richness of young sites was accompanied by a skew in species composition and absence of several species that were common in the reference sites. In contrast, genetic variation screened with neutral microsatellite markers in the lichen species Lobaria pulmonaria showed no significant differences between site categories. Our null hypothesis of a neutral species assembly in young sites corresponding to a random draw from the regional species pool was rejected, whereas an alternative hypothesis based on differences in colonization capacity among species was supported. The results indicate that for the habitat configuration in the heathland area (isolated patches constituting < 0.4% of the area) lichen communities may need a colonization time of 100-150 yr for species richness to level off, but given enough time, isolation will not affect species richness. We suggest that this contradiction to expectations from classical island equilibrium theory results from low extinction rates.

  16. Aldosterone induces myofibroblast EGF secretion to regulate epithelial colonic permeability.

    PubMed

    Miró, Lluïsa; Pérez-Bosque, Anna; Maijó, Mònica; Amat, Concepció; Naftalin, Richard J; Moretó, Miquel

    2013-05-01

    In vivo studies show that raised aldosterone (Aldo) during low-Na adaptation regulates the growth of pericryptal myofibroblasts and reduces the permeability of the colonic epithelium. The aim of this study was to reproduce in vitro the in vivo condition of increased Aldo using human CCD-18Co myofibroblasts and T84 colonic epithelial cells to measure myofibroblast and epithelial proliferation and the expression of intercellular junction proteins. Proliferation was quantified by measuring 5-bromo-2'-deoxyuridine incorporation. The myofibroblast expression of EGF, VEGFa, and transforming growth factor-β1 (TGF-β1) was measured by real-time PCR and the expression of junctional complex proteins by Western blot. Aldo stimulated the proliferation of myofibroblasts by 70% (P < 0.05) and increased EGF mRNA expression by 30% (P < 0.05) without affecting VEGFa and TGF-β1. EGF concentration in the incubation medium increased by 30% (P < 0.05) 24 h after Aldo addition, and these effects were prevented by the addition of spironolactone. Myofibroblast proliferation in response to Aldo was mediated by EGF receptor (EGFR) and involved both MAPKK and phosphatidylinositol 3-kinase pathways. When T84 cells were incubated with medium from myofibroblasts stimulated with Aldo (conditioned medium), the expression of β-catenin and claudin IV was increased by 30% (P < 0.05) and proliferation by 40% (P < 0.05). T84 proliferation decreased when α-EGF, or the EGFR antagonist AG1478, was present. Results in vivo indicate that rats fed a low-salt diet showed an increased expression of EGF and EGFR in the colonic mucosa. These results support the view that changes in colonic permeability during low-Na adaptation are mediated by the EGF secreted by myofibroblasts in response to raised Aldo. PMID:23467299

  17. Sensitivity analysis of an Ocean Carbon Cycle Model in the North Atlantic: an investigation of parameters affecting the air-sea CO2 flux, primary production and export of detritus

    NASA Astrophysics Data System (ADS)

    Scott, V.; Kettle, H.; Merchant, C. J.

    2010-12-01

    The sensitivity of the biological parameters in a nutrient-phytoplankton-zooplankton-detritus (NPZD) model in the calculation of the air-sea CO2 flux, primary production and detrital export is analysed. The NPZD model is the Hadley Centre Ocean Carbon Cycle model (HadOCC) from the UK Met Office, used in the Hadley Centre Coupled Model 3 (HadCM3) and FAst Met Office and Universities Simulator (FAMOUS) GCMs. Here, HadOCC is coupled to the 1-D General Ocean Turbulence Model (GOTM) and forced with European Centre for Medium-Range Weather Forecasting meteorology to undertake a sensitivity analysis of its twenty biological parameters. Analyses are performed at three sites in the EuroSITES European Ocean Observatory Network: the Central Irminger Sea (60° N 40° W), the Porcupine Abyssal Plain (49° N 16° W) and the European Station for Time series in the Ocean Canary Islands (29° N 15° W) to assess variability in parameter sensitivities at different locations in the North Atlantic Ocean. Reasonable changes to the values of key parameters are shown to have a large effect on the calculation of the air-sea CO2 flux, primary production, and export of biological detritus to the deep ocean. Changes in the values of key parameters have a greater effect in more productive regions than in less productive areas. We perform the analysis using one-at-a-time perturbations and using a statistical emulator, and compare results. The most sensitive parameters are generic to many NPZD ocean ecosystem models. The air-sea CO2 flux is most influenced by variation in the parameters that control phytoplankton growth, detrital sinking and carbonate production by phytoplankton (the rain ratio). Primary production is most sensitive to the parameters that define the shape of the photosythesis-irradiance curve. Export production is most sensitive to the parameters that control the rate of detrital sinking and the remineralisation of detritus.

  18. ApoE deficiency promotes colon inflammation and enhances the inflammatory potential of oxidized-LDL and TNF-α in primary colon epithelial cells

    PubMed Central

    El-Bahrawy, Ali H.; Tarhuni, Abdelmetalab; Kim, Hogyoung; Subramaniam, Venkat; Benslimane, Ilyes; Elmajeed, Zakaria Y. Abd; Okpechi, Samuel C.; Ghonim, Mohamed A.; Hemeida, Ramadan A.M.; Abo-yousef, Amira M.; El-Sherbiny, Gamal A.; Abdel-Raheem, Ihab T.; Kim, Jong; Naura, Amarjit S.; Boulares, A. Hamid

    2016-01-01

    Although deficiency in Apolipoprotein E (ApoE) is linked to many diseases, its effect on colon homoeostasis remains unknown. ApoE appears to control inflammation by regulating nuclear factor-κB (NF-κB). The present study was designed to examine whether ApoE deficiency affects factors of colon integrity in vivo and given the likelihood that ApoE deficiency increases oxidized lipids and TNF-α, the present study also examined whether such deficiency enhances the inflammatory potential of oxidized-LDL (oxLDL) and TNF-α in colon epithelial cells (CECs), in vitro. Here we show that ApoE deficiency is associated with chronic inflammation systemically and in colonic tissues as assessed by TNF-α levels. Increased colon TNF-α mRNA coincided with a substantial increase in cyclooxygenase (COX)-2. ApoE deficiency enhanced the potential of oxLDL and TNF-α to induce COX-2 expression as well as several other inflammatory factors in primary CECs. Interestingly, oxLDL enhanced TGF-β expression only in ApoE−/−, but not in wild-type, epithelial cells. ApoE deficiency appears to promote COX-2 expression enhancement through a mechanism that involves persistent NF-κB nuclear localization and PI3 and p38 MAP kinases but independently of Src. In mice, ApoE deficiency promoted a moderate increase in crypt length, which was associated with opposing effects of an increase in cell proliferation and apoptosis at the bottom and top of the crypt respectively. Our results support the notion that ApoE plays a central role in colon homoeostasis and that ApoE deficiency may constitute a risk factor for colon pathologies. PMID:27538678

  19. A pilot study comparing protein expression in different segments of the normal colon and rectum and in normal colon versus adenoma in patients with Lynch syndrome

    PubMed Central

    Wei, Chongjuan; Chen, Jinyun; Pande, Mala; Lynch, Patrick M.; Frazier, Marsha L.

    2013-01-01

    Purpose Lynch syndrome (LS) is a common inherited predisposition to colorectal cancer (CRC). In LS patients, CRC is predominantly located in the right colon, as opposed to sporadic CRC, which usually affects the left colon or rectum. Previous studies have demonstrated a clear distinction in gene expression between sporadic CRC and normal colon at different locations in the colorectum. However, little is known about LS gene expression profiles in different areas of the colorectum. Here, we compared the protein expression profiles for normal colorectal samples among different locations as well as between adenomas and matched normal tissue in LS. Methods Protein from 33 tissue samples (27 normal tissues and 6 adenomas) from 9 patients with LS was extracted for reverse-phase protein array (RPPA) analysis. The antibody panel used for RPPA included 109 key proteins involved in various cancer-related pathways. Cluster 3.0 was used for unsupervised and supervised clustering analysis. Results IGF1R and COL6A1 were expressed significantly differently between the normal right and normal left colon (q<0.05); FN1, COL6A1, and IGF1R were expressed significantly differently between the normal right colon and normal rectum (q<0.05). In the adenomas and matched normal tissue, PEA-15 was the only protein with significantly different expression (q<0.05). Conclusion We found differences in protein expression between normal tissues from the right colon, left colon, and rectum as well as between adenomas and matched normal tissue. However, those differences should be further confirmed in a larger sample size. PMID:23604467

  20. Post-discharge mortality in patients hospitalized with MRSA infection and/or colonization.

    PubMed

    Sharma, A; Rogers, C; Rimland, D; Stafford, C; Satola, S; Crispell, E; Gaynes, R

    2013-06-01

    Methicillin-resistant Staphylococcus aureus (MRSA) infection is known to increase in-hospital mortality, but little is known about its association with long-term health. Two hundred and thirty-seven deaths occurred among 707 patients with MRSA infection at the time of hospitalization and/or nasal colonization followed for almost 4 years after discharge from the Atlanta Veterans Affairs Medical Center, USA. The crude mortality rate in patients with an infection and colonization (23·57/100 person-years) was significantly higher than the rate in patients with only colonization (15·67/100 person-years, P = 0·037). MRSA infection, hospitalization within past 6 months, and histories of cancer or haemodialysis were independent risk factors. Adjusted mortality rates in patients with infection were almost twice as high compared to patients who were only colonized: patients infected and colonized [hazard ratio (HR) 1·93, 95% confidence interval (CI) 1·31-2·84]; patients infected but not colonized (HR 1·96, 95% CI 1·22-3·17). Surviving MRSA infection adversely affects long-term mortality, underscoring the importance of infection control in healthcare settings.

  1. Impact of Phytolacca americana extracts on gene expression of colon cancer cells.

    PubMed

    Maness, L; Goktepe, I; Chen, H; Ahmedna, M; Sang, S

    2014-02-01

    Native Americans have used Phytolacca americana to treat breast ailments, gastrointestinal disorders, rashes, and inflammation. Some anti-cancer and anti-viral research has been reported on this perennial herb, but none has been published concerning the effects of its extracts on cancer cell genes. In this study, changes in gene expression at the transcription level were evaluated in HCT-116 colon cancer cells after exposure to P. americana ethanol extract and its water fraction using the Human Cancer Pathway Finder PCR Array. Of the genes significantly affected in HCT-116 cells exposed to the ethanol extract at 3200 µg/ml, changes in expression of MYC, PLAU, and TEK may benefit the treatment of colon cancer. Exposing the cells to 1600 µg/ml of the water fraction resulted in several gene changes that may also be beneficial in the treatment of colon cancer: NME4, TEK, and THBS1. A few genes on this array that are known to play a specific role in colon cancer had activities changed in a way that may be detrimental in the treatment of colon cancer. Further studies should be performed to understand how these changes would impact colon cancer treatment.

  2. Lack of functioning intratumoral lymphatics in colon and pancreas cancer tissue.

    PubMed

    Olszewski, Waldemar L; Stanczyk, Marek; Gewartowska, Magdalena; Domaszewska-Szostek, Anna; Durlik, Marek

    2012-09-01

    There are controversial views as to whether intratumoral or peritumoral lymphatics play a dominant role in the metastatic process. Most clinical observations originate from studies of colon cancer. Colon contains mucosa and submucosa rich in lymphatics and with high lymph formation rate. This seems to be a prerequisite for easy metastasis of cancer cells to regional lymph nodes. However, there are other tissues as pancreas with a rudimentary lymphatic network where cancer metastasis formation is as intensive as in colon cancer. This contradicts the common notion that intratumor lymphatics play major role in metastases. We visualized interstitial space and lymphatics in the central and peripheral regions of colon and pancreas tumors using the color stereoscopic lymphography and simultaneously immunohistochemical performed stainings specific for lymphatic and blood endothelial cells. The density of open and compressed lymphatic and blood vessels was measured in the tumor core and edge. There were very few lymphatics in the colon and pancreas tumor core but numerous minor fluid "lakes" with no visible connection to the peritumoral lymphatics. Lining of "lakes" did not express molecular markers specific for lymphatic endothelial cells. Dense connective tissue surrounding tumor foci did not contain lymphatics. Peritumoral lymphatics were irregularly distributed in both types of tumor and only sporadically contained cells that might be tumor cells. Similar lymphoscintigraphic and histological pictures were seen in colon and pancreas cancer despite of different structure of both tissues. This suggests a uniform reaction of tissues to the growing cancer irrespective of the affected organ.

  3. Interleukin-8 as an autocrine growth factor for human colon carcinoma cells in vitro.

    PubMed

    Brew, R; Erikson, J S; West, D C; Kinsella, A R; Slavin, J; Christmas, S E

    2000-01-01

    Cell lines derived from human colon carcinomas secrete interleukin 8 (IL-8) in vitro and this chemokine has also been detected immunohistochemically in human colon carcinoma specimens, in which it is tumour cell associated. In these experiments, IL-8 was shown to comprise an important component of the angiogenic activity of colon carcinoma cell line supernatants. The effect of modulating IL-8 activity upon the growth of the colon carcinoma cell lines HCT116A, HT29 and CaCo2 was investigated. Supplementing endogenously produced IL-8 by recombinant chemokine led to stimulation of cell growth. Neutralization of the effect of endogenously produced IL-8, either with the specific antagonist peptide AcRRWWCR or with blocking anti-IL-8 antibody, resulted in around 50% inhibition of cell growth (P<0.05). All of the colon carcinoma cell lines tested expressed mRNA for both IL-8RA and RB when grown at confluence. At the protein level, all cell lines expressed IL-8RA. Expression of IL-8RB was weak, although increased expression was seen in HCT116A cells as they approached confluence. Antibodies to IL-8RA and RB did not affect proliferation at low cell density but were strongly inhibitory when cells were cultured at a higher density. These data suggest that IL-8 acts as an autocrine growth factor for colon carcinoma cell lines and would support the concept that a similar autocrine loop operates in vivo.

  4. Mixed Adenoneuroendocrine Carcinoma Causing Colonic Intussusception

    PubMed Central

    Pinho, André Costa; Marques, Ana; Lopes, Joanne; Duarte, Alexandre; da Silva, Pedro Correia; Lopes, José Manuel; Maia, J. Costa

    2016-01-01

    Colonic intussusception is a rare cause of intestinal obstruction in adults and is caused by a malignant lesion in about 70% of cases. Early diagnosis and treatment are essential. We present a 64-year-old male patient with right colonic intussusception caused by a mixed adenoneuroendocrine carcinoma (MANEC), presenting as a giant pedunculated polyp (54 mm of largest diameter). The patient underwent right colectomy with primary anastomosis and adjuvant chemotherapy. The diagnosis of intussusception of the colon in adults is difficult because of its rarity and nonspecific clinical presentation. In this case, the cause was a rare histological type malignant tumor (MANEC). PMID:27525153

  5. Giant ascending colonic diverticulum presenting with intussusception.

    PubMed

    Kim, Ho Jin; Kim, Jin Ha; Moon, Ok In; Kim, Kyung Jong

    2013-10-01

    Diverticular disease of the colon is a common disease, and its incidence is increasing gradually. A giant colonic diverticulum (GCD) is a rare entity and is defined as a diverticulum greater than 4 cm in size. It mainly arises from the sigmoid colon, and possible etiology is a ball-valve mechanism permitting progressive enlargement. A plain abdominal X-ray can be helpful to make a diagnosis initially, and a barium enema and abdominal computed tomography may confirm the diagnosis. Surgical intervention is a definite treatment for a GCD. We report a case of an ascending GCD presenting with intussusception in a young adult.

  6. Fra-1 is a key driver of colon cancer metastasis and a Fra-1 classifier predicts disease-free survival

    PubMed Central

    Iskit, Sedef; Schlicker, Andreas; Wessels, Lodewyk; Peeper, Daniel S.

    2015-01-01

    Fra-1 (Fos-related antigen-1) is a member of the AP-1 (activator protein-1) family of transcription factors. We previously showed that Fra-1 is necessary for breast cancer cells to metastasize in vivo, and that a classifier comprising genes that are expressed in a Fra-1-dependent fashion can predict breast cancer outcome. Here, we show that Fra-1 plays an important role also in colon cancer progression. Whereas Fra-1 depletion does not affect 2D proliferation of human colon cancer cells, it impairs growth in soft agar and in suspension. Consistently, subcutaneous tumors formed by Fra-1-depleted colon cancer cells are three times smaller than those produced by control cells. Most remarkably, when injected intravenously, Fra-1 depletion causes a 200-fold reduction in tumor burden. Moreover, a Fra-1 classifier generated by comparing RNA profiles of parental and Fra-1-depleted colon cancer cells can predict the prognosis of colon cancer patients. Functional pathway analysis revealed Wnt as one of the central pathways in the classifier, suggesting a possible mechanism of Fra-1 function in colon cancer metastasis. Our results demonstrate that Fra-1 is an important determinant of the metastatic potential of human colon cancer cells, and that the Fra-1 classifier can be used as a prognostic predictor in colon cancer patients. PMID:26646695

  7. Evidence for tachykinin NK3 receptors-triggered peptide YY release from isolated guinea-pig distal colon.

    PubMed

    Kojima, Shu-ichi; Tohei, Atsushi; Kojima, Ken; Anzai, Naohiko

    2014-10-01

    The anorectic gut hormone, peptide YY (PYY), is released from colonic mucosal endocrine cells, but little is known about the role for tachykinin NK3 receptor in the control of PYY release from the colonic mucosa. We investigated the functional role for NK3 receptors in the control of PYY release from isolated guinea-pig distal colon, and the role for NK3 receptors-triggered PYY release in the control of colonic motility. Isolated colonic preparations were mounted in organ baths for measurement of PYY release and mechanical activity. The release of PYY from these preparations was determined by enzyme immunoassays. The NK3 receptor agonist senktide produced a tetrodotoxin/atropine-sensitive sustained increase in the release of PYY from the colonic preparations. Basal PYY release was transiently inhibited by the NK3 receptor antagonist SB222200. The neuropeptide Y1 receptor antagonist BIBO3304 produced a leftward shift of the concentration-response curves for senktide-evoked neurogenic contraction, but neither the neuropeptide Y2 receptor antagonist BIIE0246 nor the neuropeptide Y5 receptor antagonist CGP71683 affected the senktide concentration-response curves. NK3 receptors appear to play an important role in the control of PYY release from colonic mucosa, and NK3 receptor-triggered PYY release can exert Y1 receptor-mediated inhibition of tachykinergic neuromuscular transmission. This indicates a pathophysiological role for the NK3 receptor-triggered PYY release in the control of colonic motility.

  8. Colonic distention at screening CT colonography: role of spasmolytic agents and body habitus.

    PubMed

    Sakamoto, Takashi; Utsunomiya, Daisuke; Mitsuzaki, Katsuhiko; Matsuda, Katsuhiko; Kawakami, Megumi; Yamamura, Sadahiro; Urata, Joji; Arakawa, Akihiko; Yamashita, Yasuyuki

    2014-01-01

    Sufficient colonic dilation is important when using CT colonography (CTC) for colorectal cancer screening. We investigated the effect of antispasmodic agents and the patient body habitus on the degree of colonic dilation in screening CTC.We assessed the effect of clinical characteristics [age, gender, body mass index (BMI), and the presence of diverticula] and the use of antispasmodics on colonic distention in 140 patients who underwent CTC for colorectal cancer screening. The CTC was performed in both the supine- and prone positions. Seventy patients received antispasmodics prior to CT examination and the other 70 did not. Colonic distention was scored using a 5-point scale: 1=collapsed, 2=poorly visualized, 3=visualized but underdistended, 4=acceptable, and 5=excellent. Images scored as 4 or 5 were considered to be of diagnostic quality. The mean visual evaluation score was significantly higher in the supine- than the prone position (4.2±0.5 vs. 4.0±0.5, p<0.01). For the supine position, only the use of antispasmodic was statistically associated with sufficient colonic dilation by univariate logistic analysis (odds ratio=2.365, p=0.03). For the prone position, age, BMI, and the use of antispasmodic were statistically associated with sufficient colonic dilation by multivariate analysis. The odds ratio of these parameters was 0.955 (p=0.02), 0.874 (p=0.03), and 2.391 (p=0.02), respectively.We obtained sufficient colonic dilation with an antispasmodic for CTC in both positions. Younger age and a lower BMI were also associated with better colonic dilation in the prone position.

  9. Butyrate modulates antioxidant enzyme expression in malignant and non-malignant human colon tissues.

    PubMed

    Jahns, Franziska; Wilhelm, Anne; Jablonowski, Nadja; Mothes, Henning; Greulich, Karl Otto; Glei, Michael

    2015-04-01

    The induction of antioxidant enzymes is an important mechanism in colon cancer chemoprevention, but the response of human colon tissue to butyrate, a gut fermentation product derived from dietary fiber, remains largely unknown. Therefore, our study investigated the effect of a butyrate treatment on catalase (CAT) and superoxide dismutase (SOD2) in matched human colon tissues of different transformation stages (n = 3-15 in each group) ex vivo. By performing quantitative real-time PCR, Western blot, and spectrophotometric measurements, we found an increase in SOD2 at expression and activity level in colonic adenocarcinomas (mRNA: 1.96-fold; protein: 1.41-fold, activity: 1.8-fold; P < 0.05). No difference was detectable for CAT between normal, adenoma, and carcinoma colon tissues. Treatment of normal colon epithelium (12 h) with a physiologically relevant concentration of butyrate (10 mM) resulted in a significant increase (P < 0.05) in CAT mRNA (1.24-fold) and protein (1.39-fold), without affecting the enzymatic activity. Consequently, preliminary experiments failed to show any protective effect of butyrate against H2 O2 -mediated DNA damage. Despite a significantly lowered SOD2 transcript (0.51-fold, P < 0.01) and, to a lesser extent, protein level (0.86-fold) after butyrate exposure of normal colon cells, the catalytic activity was significantly enhanced (1.19-fold, P < 0.05), suggesting an increased protection against tissue superoxide radicals. In malignant tissues, greater variations in response to butyrate were observed. Furthermore, both enzymes showed an age-dependent decrease in activity in normal colon epithelium (CAT: r = -0.49, P = 0.09; SOD2: r = -0.58, P = 0.049). In conclusion, butyrate exhibited potential antioxidant features ex vivo but cellular consequences need to be investigated more in depth.

  10. The Value of Continuity between Primary Care and Surgical Care in Colon Cancer

    PubMed Central

    Hussain, Tanvir; Chang, Hsien-Yen; Luu, Ngoc-Phuong; Pollack, Craig Evan

    2016-01-01

    Background Improving continuity between primary care and cancer care is critical for improving cancer outcomes and curbing cancer costs. A dimension of continuity, we investigated how regularly patients receive their primary care and surgical care for colon cancer from the same hospital and whether this affects mortality and costs. Methods Using Surveillance, Epidemiology, and End Results Program Registry (SEER)-Medicare data, we performed a retrospective cohort study of stage I-III colon cancer patients diagnosed between 2000 and 2009. There were 23,305 stage I-III colon cancer patients who received primary care in the year prior to diagnosis and underwent operative care for colon cancer. Patients were assigned to the hospital where they had their surgery and to their primary care provider’s main hospital, and then classified according to whether these two hospitals were same or different. Outcomes examined were hazards for all-cause mortality, subhazard for colon cancer specific mortality, and generalized linear estimate for costs at 12 months, from propensity score matched models. Results Fifty-two percent of stage I-III colon patients received primary care and surgical care from the same hospital. Primary care and surgical care from the same hospital was not associated with reduced all-cause or colon cancer specific mortality, but was associated with lower inpatient, outpatient, and total costs of care. Total cost difference was $8,836 (95% CI $2,746–$14,577), a 20% reduction in total median cost of care at 12 months. Conclusions Receiving primary care and surgical care at the same hospital, compared to different hospitals, was associated with lower costs but still similar survival among stage I-III colon cancer patients. Nonetheless, health care policy which encourages further integration between primary care and cancer care in order to improve outcomes and decrease costs will need to address the significant proportion of patients receiving health care

  11. Nitrergic signalling via interstitial cells of Cajal regulates motor activity in murine colon.

    PubMed

    Lies, Barbara; Beck, Katharina; Keppler, Jonas; Saur, Dieter; Groneberg, Dieter; Friebe, Andreas

    2015-10-15

    In the enteric nervous systems, NO is released from nitrergic neurons as a major inhibitory neurotransmitter. NO acts via NO-sensitive guanylyl cyclase (NO-GC), which is found in different gastrointestinal (GI) cell types including smooth muscle cells (SMCs) and interstitial cells of Cajal (ICC). The precise mechanism of nitrergic signalling through these two cell types to regulate colonic spontaneous contractions is not fully understood yet. In the present study we investigated the impact of endogenous and exogenous NO on colonic contractile motor activity using mice lacking nitric oxide-sensitive guanylyl cyclase (NO-GC) globally and specifically in SMCs and ICC. Longitudinal smooth muscle of proximal colon from wild-type (WT) and knockout (KO) mouse strains exhibited spontaneous contractile activity ex vivo. WT and smooth muscle-specific guanylyl cyclase knockout (SMC-GCKO) colon showed an arrhythmic contractile activity with varying amplitudes and frequencies. In contrast, colon from global and ICC-specific guanylyl cyclase knockout (ICC-GCKO) animals showed a regular contractile rhythm with constant duration and amplitude of the rhythmic contractions. Nerve blockade (tetrodotoxin) or specific blockade of NO signalling (L-NAME, ODQ) did not significantly affect contractions of GCKO and ICC-GCKO colon whereas the arrhythmic contractile patterns of WT and SMC-GCKO colon were transformed into uniform motor patterns. In contrast, the response to electric field-stimulated neuronal NO release was similar in SMC-GCKO and global GCKO. In conclusion, our results indicate that basal enteric NO release acts via myenteric ICC to influence the generation of spontaneous contractions whereas the effects of elevated endogenous NO are mediated by SMCs in the murine proximal colon.

  12. Low concentrations of resveratrol inhibit Wnt signal throughput in colon-derived cells: Implications for colon cancer prevention

    PubMed Central

    Hope, Christopher; Kestutis, Planutis; Marina, Planutiene; Moyer, Mary P.; Johal, Karanjodh S.; Woo, Jaesung; Santoso, Calista; Hanson, Joseph A.; Holcombe, Randall F.

    2008-01-01

    Resveratrol is a bioflavonoid which is known to inhibit cell proliferation and induce apoptosis in cancer cell lines at concentrations above 50uM. It also has colon cancer prevention activity in mouse models and possibly in humans. We have examined the effects of low concentrations of resveratrol on a specific signaling pathway, the Wnt pathway, which is activated in over 85% of sporadic colon cancers. Two colon cancer (HT29 and RKO) and one normal mucosa-derived (NCM460) cell lines were utilized. Cell proliferation was not affected by resveratrol at ≤40uM for HT29 and NCM460 and <20uM for RKO though Wnt signal throughput, as measured by a reporter construct, was reduced in RKO and NCM460 at concentrations as low as 10uM (p<0.001). This effect was most easily appreciated following Wnt pathway stimulation with Wnt3a conditioned medium and LEF1 or LEF1/β-catenin transfection. Resveratrol did not inhibit Wnt throughput in mutationally activated HT29. Low concentrations of resveratrol significantly decreased the amount and proportion of β-catenin in the nucleus in RKO (p=0.002) and reduced the expression of lgs and pygoI, regulators of β-catenin localization in all cells lines. Thus, at low concentrations, in the absence of effects on cell proliferation, resveratrol significantly inhibits Wnt signaling in colon-derived cells which do not have a basally activated Wnt pathway. This inhibitory effect may be due in part to regulation of intracellular β-catenin localization. PMID:18504708

  13. Post-translational glycoprotein modifications regulate colon cancer stem cells and colon adenoma progression in Apc(min/+) mice through altered Wnt receptor signaling.

    PubMed

    Guo, Huabei; Nagy, Tamas; Pierce, Michael

    2014-11-01

    Deletion of GnT-V (MGAT5), which synthesizes N-glycans with β(1,6)-branched glycans, reduced the compartment of cancer stem cells (CSC) in the her-2 mouse model of breast cancer, leading to delay of tumor onset. Because GnT-V levels are also commonly up-regulated in colon cancer, we investigated their regulation of colon CSC and adenoma development. Anchorage-independent cell growth and tumor formation induced by injection of colon tumor cells into NOD/SCID mice were positively associated with GnT-V levels, indicating regulation of proliferation and tumorigenicity. Using Apc(min/+) mice with different GnT-V backgrounds, knock-out of GnT-V had no significant effect on the number of adenoma/mouse, but adenoma size was significantly reduced and accompanied increased survival of Apc(min/+) mice with GnT-V deletion (p < 0.01), suggesting an inhibition in the progression of colon adenoma caused by deletion of GnT-V. Decreased expression levels of GnT-V down-regulated the population of colon (intestine) CSC, affecting their ability for self-renewal and tumorigenicity in NOD/SCID mice. Furthermore, altered nuclear translocation of β-catenin and expression of Wnt target genes were positively associated with expression levels of GnT-V, indicating the regulation of canonical Wnt/β-catenin signaling. By overexpressing the Wnt receptor, FZD-7, in colon cancer cells, we found that FZD-7 receptors expressed N-linked β(1,6) branching, indicating that FZD-7 can be modified by GnT-V. The aberrant Wnt signaling observed after modulating GnT-V levels is likely to result from altered N-linked β(1,6) branching on FZD-7, thereby affecting Wnt signaling, the compartment of CSC, and tumor progression.

  14. Effects of female steroid hormones on A-type K+ currents in murine colon

    PubMed Central

    Beckett, Elizabeth A H; McCloskey, Conor; O'Kane, Neil; Sanders, Kenton M; Don Koh, Sang

    2006-01-01

    Idiopathic constipation is higher in women of reproductive age than postmenopausal women or men, suggesting that female steroid hormones influence gastrointestinal motility. How female hormones affect motility is unclear. Colonic motility is regulated by ion channels in colonic myocytes. Voltage-dependent K+ channels serve to set the excitability of colonic muscles. We investigated regulation of Kv4.3 channel expression in response to acute or chronic changes in female hormones. Patch clamp experiments and quantitative PCR were used to compare outward currents and transcript expression in colonic myocytes from male, non-pregnant, pregnant and ovariectomized mice. Groups of ovariectomized mice received injections of oestrogen or progesterone to investigate the effects of hormone replacement. The capacitance of colonic myocytes from non-pregnant females was larger than in males. Net outward current density in male and ovariectomized mice was higher than in non-pregnant females and oestrogen-treated ovariectomized mice. Current densities in late pregnancy were lower than in female controls. Progesterone had no effect on outward currents. A-type currents were decreased in non-pregnant females compared with ovariectomized mice, and were further decreased by pregnancy or oestrogen replacement. Kv4.3 transcripts did not differ significantly between groups; however, expression of the potassium channel interacting protein KChIP1 was elevated in ovariectomized mice compared with female controls and oestrogen-treated ovariectomized mice. Delayed rectifier currents were not affected by oestrogen. In the mouse colon, oestrogen suppresses A-type currents, which are important for regulating excitability. These observations suggest a possible link between female hormones and altered colonic motility associated with menses, pregnancy and menopause. PMID:16581861

  15. Drugs Approved for Colon and Rectal Cancer

    Cancer.gov

    This page lists cancer drugs approved by the Food and Drug Administration (FDA) for use in colon cancer and rectal cancer. The list includes generic names, brand names, and common drug combinations, which are shown in capital letters.

  16. Colon Cancer Risk Assessment - Gauss Program

    Cancer.gov

    An executable file (in GAUSS) that projects absolute colon cancer risk (with confidence intervals) according to NCI’s Colorectal Cancer Risk Assessment Tool (CCRAT) algorithm. GAUSS is not needed to run the program.

  17. Redefining Adjuvant Therapy for Colon Cancer

    Cancer.gov

    In this trial, patients with resected stage III colon cancer are being randomly assigned to receive FOLFOX chemotherapy for either 3 or 6 months and to take either a pill called celecoxib or a matching placebo pill for 3 years.

  18. Marine worms (genus Osedax) colonize cow bones

    PubMed Central

    Jones, William J; Johnson, Shannon B; Rouse, Greg W; Vrijenhoek, Robert C

    2007-01-01

    Bone-eating worms of the genus Osedax colonized and grew on cow bones deployed at depths ranging from 385 to 2893 m in Monterey Bay, California. Colonization occurred as rapidly as two months following deployment of the cow bones, similar to the time it takes to colonize exposed whalebones. Some Osedax females found on the cow bones were producing eggs and some hosted dwarf males in their tubes. Morphological and molecular examinations of these worms confirmed the presence of six Osedax species, out of the eight species presently known from Monterey Bay. The ability of Osedax species to colonize, grow and reproduce on cow bones challenges previous notions that these worms are ‘whale-fall specialists.’ PMID:18077256

  19. [Management of traumatic injuries of the colon].

    PubMed

    Wong, J C; Quintero, O; Andrade, R

    1989-01-01

    We have reviewed our experience with penetrating lesions of the colon at the Santo Tomás Hospital. Good results were obtained with immediate suture of the lesions without need for colostomy when favorable conditions permit.

  20. Intestinal Colonization Dynamics of Vibrio cholerae

    PubMed Central

    Almagro-Moreno, Salvador; Pruss, Kali; Taylor, Ronald K.

    2015-01-01

    To cause the diarrheal disease cholera, Vibrio cholerae must effectively colonize the small intestine. In order to do so, the bacterium needs to successfully travel through the stomach and withstand the presence of agents such as bile and antimicrobial peptides in the intestinal lumen and mucus. The bacterial cells penetrate the viscous mucus layer covering the epithelium and attach and proliferate on its surface. In this review, we discuss recent developments and known aspects of the early stages of V. cholerae intestinal colonization and highlight areas that remain to be fully understood. We propose mechanisms and postulate a model that covers some of the steps that are required in order for the bacterium to efficiently colonize the human host. A deeper understanding of the colonization dynamics of V. cholerae and other intestinal pathogens will provide us with a variety of novel targets and strategies to avoid the diseases caused by these organisms. PMID:25996593

  1. Preventing Second Cancers in Colon Cancer Survivors

    Cancer.gov

    In this phase III trial, people who have had curative surgery for colon cancer will be randomly assigned to take sulindac and a placebo, eflornithine and a placebo, both sulindac and eflornithine, or two placebo pills for 36 months.

  2. [Ultrasonography in the diagnosis of colonic obstruction].

    PubMed

    Legostaeva, T B; Klassovskaia, N Iu

    2007-01-01

    The authors of the present paper outline the results of studying the use of routine transabdominal sonography and ultrasound irrigoscopy (UI) in the diagnosis of acute colonic obstruction (ACO) in 70 patients. The cause of ACO was tumor-induced colonic luminal obturation in 55 patients and colonic evacuatory dysfunction due to congenital anomalies and acquired constrictions of inflammatory genesis in 15 cases. UI was used to determine the presence, degree, and causes of colonic obstruction. The paper details the UI procedure developed by the authors and the ultrasound semiotics of ACO, shown by routine transabdominal sonography and UI. Analysis of the results of the studies allows the authors to state that UI is as highly informative as X-ray irrigoscopy in the diagnosis of ACO and may be included into a diagnostic algorithm in these patients.

  3. Non-surgical factors influencing lymph node yield in colon cancer

    PubMed Central

    Wood, Patrick; Peirce, Colin; Mulsow, Jurgen

    2016-01-01

    There are numerous factors which can affect the lymph node (LN) yield in colon cancer specimens. The aim of this paper was to identify both modifiable and non-modifiable factors that have been demonstrated to affect colonic resection specimen LN yield and to summarise the pertinent literature on these topics. A literature review of PubMed was performed to identify the potential factors which may influence the LN yield in colon cancer resection specimens. The terms used for the search were: LN, lymphadenectomy, LN yield, LN harvest, LN number, colon cancer and colorectal cancer. Both non-modifiable and modifiable factors were identified. The review identified fifteen non-surgical factors: (13 non-modifiable, 2 modifiable) which may influence LN yield. LN yield is frequently reduced in older, obese patients and those with male sex and increased in patients with right sided, large, and poorly differentiated tumours. Patient ethnicity and lower socioeconomic class may negatively influence LN yield. Pre-operative tumour tattooing appears to increase LN yield. There are many factors that potentially influence the LN yield, although the strength of the association between the two varies greatly. Perfecting oncological resection and pathological analysis remain the cornerstones to achieving good quality and quantity LN yields in patients with colon cancer. PMID:27190586

  4. Effects of airborne particulate matter on alternative pre-mRNA splicing in colon cancer cells

    SciTech Connect

    Buggiano, Valeria; Petrillo, Ezequiel; Alló, Mariano; Lafaille, Celina; Redal, María Ana; Alghamdi, Mansour A.; Khoder, Mamdouh I.; Shamy, Magdy; Muñoz, Manuel J.; and others

    2015-07-15

    Alternative pre-mRNA splicing plays key roles in determining tissue- and species-specific cell differentiation as well as in the onset of hereditary disease and cancer, being controlled by multiple post- and co-transcriptional regulatory mechanisms. We report here that airborne particulate matter, resulting from industrial pollution, inhibits expression and specifically affects alternative splicing at the 5′ untranslated region of the mRNA encoding the bone morphogenetic protein BMP4 in human colon cells in culture. These effects are consistent with a previously reported role for BMP4 in preventing colon cancer development, suggesting that ingestion of particulate matter could contribute to the onset of colon cell proliferation. We also show that the underlying mechanism might involve changes in transcriptional elongation. This is the first study to demonstrate that particulate matter causes non-pleiotropic changes in alternative splicing. - Highlights: • Airborne particulate matter (PM10) affects alternative splicing in colon cells. • PM10 upregulates one of the two mRNA variants of the growth factor BMP-4. • This variant has a longer 5′ unstranslated region and introduces an upstream AUG. • By regulating BMP-4 mRNA splicing PM10 inhibits total expression of BMP-4 protein. • BMP-4 downregulation was previously reported to be associated to colon cancer.

  5. Colonic transit in rats: effect of ovariectomy, sex steroid hormones, and pregnancy

    SciTech Connect

    Ryan, J.P.; Bhojwani, A.

    1986-07-01

    In vitro studies suggest that the female sex steroid hormones (estrogen (E) and progesterone (P)) can affect the myoelectric and mechanical activity of colonic smooth muscle. The present study was designed to examine the influence of the hormones on colonic transit in vivo. Transit was assessed by quantifying the distribution within the colon of a radiolabeled marker (0.5 Ci Na2V CrO4), using the geometric center method of analysis. Studies were performed with adult male rats and the following groups of female rats: nonpregnant, ovariectomized, ovariectomy plus hormone pretreatment, and pregnant (day 18). Hormone-pretreated animals were studied 24 h following the fourth injection. The data can be summarized as follows. 1) Colonic transit was affected by the timing of the estrus cycle. 2) Ovariectomy eliminated the biphasic transit pattern observed in estruscycling females and resulted in a geometric center value comparable with that of the metestrus-diestrus animals. 3) E + P pretreatment of ovariectomized rats resulted in a significant decrease in the geometric center compared with the untreated ovariectomized rats. 4) The geometric center value in pregnant anials and hormone-pretreated animals. 5) Adult male rats had a geometric center value of 4.12 +/- 0.29. The results suggest that a relation exists between colonic transit and the circulating levels of the steroid hormones.

  6. Non-surgical factors influencing lymph node yield in colon cancer.

    PubMed

    Wood, Patrick; Peirce, Colin; Mulsow, Jurgen

    2016-05-15

    There are numerous factors which can affect the lymph node (LN) yield in colon cancer specimens. The aim of this paper was to identify both modifiable and non-modifiable factors that have been demonstrated to affect colonic resection specimen LN yield and to summarise the pertinent literature on these topics. A literature review of PubMed was performed to identify the potential factors which may influence the LN yield in colon cancer resection specimens. The terms used for the search were: LN, lymphadenectomy, LN yield, LN harvest, LN number, colon cancer and colorectal cancer. Both non-modifiable and modifiable factors were identified. The review identified fifteen non-surgical factors: (13 non-modifiable, 2 modifiable) which may influence LN yield. LN yield is frequently reduced in older, obese patients and those with male sex and increased in patients with right sided, large, and poorly differentiated tumours. Patient ethnicity and lower socioeconomic class may negatively influence LN yield. Pre-operative tumour tattooing appears to increase LN yield. There are many factors that potentially influence the LN yield, although the strength of the association between the two varies greatly. Perfecting oncological resection and pathological analysis remain the cornerstones to achieving good quality and quantity LN yields in patients with colon cancer. PMID:27190586

  7. Triclosan promotes Staphylococcus aureus nasal colonization.

    PubMed

    Syed, Adnan K; Ghosh, Sudeshna; Love, Nancy G; Boles, Blaise R

    2014-01-01

    The biocide triclosan is used in many personal care products, including toothpastes, soaps, clothing, and medical equipment. Consequently, it is present as a contaminant in the environment and has been detected in some human fluids, including serum, urine, and milk. Staphylococcus aureus is an opportunistic pathogen that colonizes the noses and throats of approximately 30% of the population. Colonization with S. aureus is known to be a risk factor for several types of infection. Here we demonstrate that triclosan is commonly found in the nasal secretions of healthy adults and the presence of triclosan trends positively with nasal colonization by S. aureus. We demonstrate that triclosan can promote the binding of S. aureus to host proteins such as collagen, fibronectin, and keratin, as well as inanimate surfaces such as plastic and glass. Lastly, triclosan-exposed rats are more susceptible to nasal colonization with S. aureus. These data reveal a novel factor that influences the ability of S. aureus to bind surfaces and alters S. aureus nasal colonization. IMPORTANCE Triclosan has been used as a biocide for over 40 years, but the broader effects that it has on the human microbiome have not been investigated. We demonstrate that triclosan is present in nasal secretions of a large portion of a test population and its presence correlates with Staphylococcus aureus nasal colonization. Triclosan also promotes the binding of S. aureus to human proteins and increases the susceptibility of rats to nasal colonization by S. aureus. These findings are significant because S. aureus colonization is a known risk factor for the development of several types of infections. Our data demonstrate the unintended consequences of unregulated triclosan use and contribute to the growing body of research demonstrating inadvertent effects of triclosan on the environment and human health. PMID:24713325

  8. Oncolytic reovirus against ovarian and colon cancer.

    PubMed

    Hirasawa, Kensuke; Nishikawa, Sandra G; Norman, Kara L; Alain, Tommy; Kossakowska, Anna; Lee, Patrick W K

    2002-03-15

    Reovirus selectively replicates in and destroys cancer cells with an activated Ras signaling pathway. In this study, we evaluated the feasibility of using reovirus (serotype 3, strain Dearing) as an antihuman colon and ovarian cancer agent. In in vitro studies, reovirus infection in human colon and ovarian cell lines was assessed by cytopathic effect as detected by light microscopy, [(35)S]Methionine labeling of infected cells for viral protein synthesis and progeny virus production by plaque assay. We observed that reovirus efficiently infected all five human colon cancer cell lines (Caco-2, DLD-1, HCT-116, HT-29, and SW48) and four human ovarian cancer cell lines (MDAH2774, PA-1, SKOV3, and SW626) which were tested, but not a normal colon cell line (CCD-18Co) or a normal ovarian cell line (NOV-31). We also observed that the Ras activity in the human colon and ovarian cancer cell lines was elevated compared with that in normal colon and ovarian cell lines. In animal models, intraneoplastic as well as i.v. inoculation of reovirus resulted in significant regression of established s.c. human colon and ovarian tumors implanted at the hind flank. Histological studies revealed that reovirus infection in vivo was restricted to tumor cells, whereas the surrounding normal tissue remained uninfected. Additionally, in an i.p. human ovarian cancer xenograft model, inhibition of ascites tumor formation and the survival of animals treated with live reovirus was significantly greater than of control mice treated with UV-inactivated reovirus. Reovirus infection in ex vivo primary human ovarian tumor surgical samples was also confirmed, further demonstrating the potential of reovirus therapy. These results suggest that reovirus holds promise as a novel agent for human colon and ovarian cancer therapy. PMID:11912142

  9. Osteopathic manipulative treatment for colonic inertia.

    PubMed

    Cohen-Lewe, Adam

    2013-03-01

    Surgical treatment options for patients with colonic inertia are costly and do not always relieve the pain associated with the condition. The author describes a case of a 41-year-old woman with colonic inertia who received osteopathic manipulative treatment targeted at the neuromusculoskeletal and gastrointestinal systems. The patient reported temporary improvement in pain and bowel function without pharmacotherapy or surgical intervention. Osteopathic manipulative treatment should be considered in patients with visceral as well as neuromusculoskeletal symptoms.

  10. Accessory spleen hypertrophy mimicking colon cancer metastasis.

    PubMed

    Ates, I; Yazici, O; Yazilitas, D; Ozdemir, N; Zengin, N

    2016-09-01

    Accessory spleen is a congenital form of an ectopic splenic tissue. In this report, we present a case of a patient who was followed with the diagnosis of rectal and sigmoid colon cancer and an accessory spleen hypertrophy, which was thought to be colon cancer metastasis in the left hypochondriac region. After colectomy and splenectomy, accessory spleen that mimics cancer metastasis was diffrentially diagnosed using scintigraphy. PMID:27685531

  11. Triclosan promotes Staphylococcus aureus nasal colonization.

    PubMed

    Syed, Adnan K; Ghosh, Sudeshna; Love, Nancy G; Boles, Blaise R

    2014-04-08

    The biocide triclosan is used in many personal care products, including toothpastes, soaps, clothing, and medical equipment. Consequently, it is present as a contaminant in the environment and has been detected in some human fluids, including serum, urine, and milk. Staphylococcus aureus is an opportunistic pathogen that colonizes the noses and throats of approximately 30% of the population. Colonization with S. aureus is known to be a risk factor for several types of infection. Here we demonstrate that triclosan is commonly found in the nasal secretions of healthy adults and the presence of triclosan trends positively with nasal colonization by S. aureus. We demonstrate that triclosan can promote the binding of S. aureus to host proteins such as collagen, fibronectin, and keratin, as well as inanimate surfaces such as plastic and glass. Lastly, triclosan-exposed rats are more susceptible to nasal colonization with S. aureus. These data reveal a novel factor that influences the ability of S. aureus to bind surfaces and alters S. aureus nasal colonization. IMPORTANCE Triclosan has been used as a biocide for over 40 years, but the broader effects that it has on the human microbiome have not been investigated. We demonstrate that triclosan is present in nasal secretions of a large portion of a test population and its presence correlates with Staphylococcus aureus nasal colonization. Triclosan also promotes the binding of S. aureus to human proteins and increases the susceptibility of rats to nasal colonization by S. aureus. These findings are significant because S. aureus colonization is a known risk factor for the development of several types of infections. Our data demonstrate the unintended consequences of unregulated triclosan use and contribute to the growing body of research demonstrating inadvertent effects of triclosan on the environment and human health.

  12. Clinical utility of colonic manometry in slow transit constipation

    PubMed Central

    Singh, Siddharth; Heady, Sarah; Coss-Adame, Enrique; Rao, Satish S.C.

    2013-01-01

    Background and Aims The clinical significance of colorectal sensori-motor evaluation in patients with slow transit constipation (STC) is unclear. We investigated whether colonic manometric evaluation is useful for characterizing colonic sensorimotor dysfunction and for guiding therapy in STC. Methods 24-hour ambulatory colonic manometry was performed in 80 patients (70 females) with STC by placing a 6 sensor solid state probe, along with assessment of colonic sensation with barostat. Anorectal manometry was also performed. Manometrically, patients were categorized as having colonic neuropathy or myopathy based on gastrocolonic response, waking response and high amplitude propagated contractions (HAPC); and based on colonic sensation, as colonic hyposensitivity or hypersensitivity. Clinical response to pharmacological, biofeedback and surgical treatment was assessed at 1yr and correlated with manometric findings. Results 59% of patients had abnormal colonic manometry with features suggestive of neuropathy (26%), and myopathy (33%); 41% had normal colonic manometry. 74% patients had abnormal colonic sensation and 61% had overlapping dyssynergic defecation. Patients with neuropathy were more likely to have colonic hyposensitivity. 64% of patients with colonic myopathy or normal manometry improved with medical/biofeedback therapy when compared to 15% with colonic neuropathy (p<0.01). Selected patients with colonic neuropathy had excellent response to surgery, but many developed bacterial overgrowth. Conclusions Colonic manometry demonstrates significant colonic sensori-motor dysfunction in STC patients and reveals considerable pathophysiological heterogeneity. It can be useful for characterizing the underlying pathophysiology and for guiding clinical management in STC, especially surgery. PMID:23384415

  13. Genetics of the pig tapeworm in Madagascar reveal a history of human dispersal and colonization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An intricate history of human dispersal and geographic colonization has strongly affected the distribution of obligate parasites circulating among people. Among these parasites, the pig tapeworm Taenia solium occurs throughout the world as the causative agent of cysticercosis, one of the most serio...

  14. Integrating multiple analytical datasets to compare metabolite profiles of mouse colonic-cecal contents and feces

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The pattern of metabolites produced by the gut microbiome comprises a phenotype indicative of the means by which that microbiome affects the gut. We characterized that phenotype in mice by conducting metabolomic analyses of the colonic-cecal contents, comparing that to the metabolite patterns of fec...

  15. Malakoplakia and colonic adenoma: a rare association.

    PubMed

    Rizzo, Elena; Sandmeier, Dominique; Hack, Isabelle; Matter, Maurice; Bouzourene, Hanifa

    2004-12-01

    We report the case of a 73-year-old woman who presented respectively a caecal adenocarcinoma, two high-grade dysplastic tubulo-villous adenomas of the right colon, and a well differentiated adenocarcinoma developed on a high-grade dysplastic tubulo-villous adenoma of the left colon. One of the right colonic adenomas was ulcerated and showed typical foci of malakoplakia in the lamina propria. Malakoplakia is a histiocytic inflammatory response that may be associated with inflammatory and infectious diseases, immunosuppressive therapy, or colorectal carcinoma. Association of malakoplakia with colonic adenoma is rare; only three cases have been described in the literature thus far. To verify if this association is more common than usually suspected, we reviewed 100 colonic adenomas measuring at least 2 cm. No other case of malakoplakia associated with adenoma was found. The patient did not suffer from any other inflammatory or infectious disease and she was not under any medication or immunosuppressive therapy. Our observation confirms the isolated association of malakoplakia and colonic adenomas and the rarity of this association.

  16. Colonic microbiome is altered in alcoholism

    PubMed Central

    Mutlu, Ece A.; Gillevet, Patrick M.; Rangwala, Huzefa; Sikaroodi, Masoumeh; Naqvi, Ammar; Engen, Phillip A.; Kwasny, Mary; Lau, Cynthia K.

    2012-01-01

    Several studies indicate the importance of colonic microbiota in metabolic and inflammatory disorders and importance of diet on microbiota composition. The effects of alcohol, one of the prominent components of diet, on colonic bacterial composition is largely unknown. Mounting evidence suggests that gut-derived bacterial endotoxins are cofactors for alcohol-induced tissue injury and organ failure like alcoholic liver disease (ALD) that only occur in a subset of alcoholics. We hypothesized that chronic alcohol consumption results in alterations of the gut microbiome in a subgroup of alcoholics, and this may be responsible for the observed inflammatory state and endotoxemia in alcoholics. Thus we interrogated the mucosa-associated colonic microbiome in 48 alcoholics with and without ALD as well as 18 healthy subjects. Colonic biopsy samples from subjects were analyzed for microbiota composition using length heterogeneity PCR fingerprinting and multitag pyrosequencing. A subgroup of alcoholics have an altered colonic microbiome (dysbiosis). The alcoholics with dysbiosis had lower median abundances of Bacteroidetes and higher ones of Proteobacteria. The observed alterations appear to correlate with high levels of serum endotoxin in a subset of the samples. Network topology analysis indicated that alcohol use is correlated with decreased connectivity of the microbial network, and this alteration is seen even after an extended period of sobriety. We show that the colonic mucosa-associated bacterial microbiome is altered in a subset of alcoholics. The altered microbiota composition is persistent and correlates with endotoxemia in a subgroup of alcoholics. PMID:22241860

  17. Colonic microbiome is altered in alcoholism.

    PubMed

    Mutlu, Ece A; Gillevet, Patrick M; Rangwala, Huzefa; Sikaroodi, Masoumeh; Naqvi, Ammar; Engen, Phillip A; Kwasny, Mary; Lau, Cynthia K; Keshavarzian, Ali

    2012-05-01

    Several studies indicate the importance of colonic microbiota in metabolic and inflammatory disorders and importance of diet on microbiota composition. The effects of alcohol, one of the prominent components of diet, on colonic bacterial composition is largely unknown. Mounting evidence suggests that gut-derived bacterial endotoxins are cofactors for alcohol-induced tissue injury and organ failure like alcoholic liver disease (ALD) that only occur in a subset of alcoholics. We hypothesized that chronic alcohol consumption results in alterations of the gut microbiome in a subgroup of alcoholics, and this may be responsible for the observed inflammatory state and endotoxemia in alcoholics. Thus we interrogated the mucosa-associated colonic microbiome in 48 alcoholics with and without ALD as well as 18 healthy subjects. Colonic biopsy samples from subjects were analyzed for microbiota composition using length heterogeneity PCR fingerprinting and multitag pyrosequencing. A subgroup of alcoholics have an altered colonic microbiome (dysbiosis). The alcoholics with dysbiosis had lower median abundances of Bacteroidetes and higher ones of Proteobacteria. The observed alterations appear to correlate with high levels of serum endotoxin in a subset of the samples. Network topology analysis indicated that alcohol use is correlated with decreased connectivity of the microbial network, and this alteration is seen even after an extended period of sobriety. We show that the colonic mucosa-associated bacterial microbiome is altered in a subset of alcoholics. The altered microbiota composition is persistent and correlates with endotoxemia in a subgroup of alcoholics. PMID:22241860

  18. Colon cancer: genomics and apoptotic events.

    PubMed

    Rupnarain, Charleen; Dlamini, Zodwa; Naicker, Sarala; Bhoola, Kanti

    2004-06-01

    Colon cancer is the third most common cancer globally. The risk of developing colon cancer is influenced by a number of factors that include age and diet, but is primarily a genetic disease, resulting from oncogene over-expression and tumour suppressor gene inactivation. The induction and progression of the disease is briefly outlined, as are the cellular changes that occur in its progression. While colon cancer is uniformly amenable to surgery if detected at the early stages, advanced carcinomas are usually lethal, with metastases to the liver being the most common cause of death. Oncogenes and genetic mutations that occur in colon cancer are featured. The molecules and signals that act to eradicate or initiate the apoptosis cascade in cancer cells, are elucidated, and these include caspases, Fas, Bax, Bid, APC, antisense hTERT, PUMA, 15-LOX-1, ceramide, butyrate, tributyrin and PPARgamma, whereas the molecules which promote colon cancer cell survival are p53 mutants, Bcl-2, Neu3 and COX-2. Cancer therapies aimed at controlling colon cancer are reviewed briefly. PMID:15255176

  19. The colon: from banal to brilliant.

    PubMed

    Sellers, Rani S; Morton, Daniel

    2014-01-01

    The colon serves as the habitat for trillions of microbes, which it must maintain, regulate, and sequester. This is managed by what is termed the mucosal barrier. The mucosal barrier separates the gut flora from the host tissues; regulates the absorption of water, electrolytes, minerals, and vitamins; and facilitates host-flora interactions. Colonic homeostasis depends on a complex interaction between the microflora and the mucosal epithelium, immune system, vasculature, stroma, and nervous system. Disruptions in the colonic microenvironment such as changes in microbial composition, epithelial cell function/proliferation/differentiation, mucus production/makeup, immune function, diet, motility, or blood flow may have substantial local and systemic consequences. Understanding the complex activities of the colon in health and disease is important in drug development, as xenobiotics can impact all segments of the colon. Direct and indirect effects of pharmaceuticals on intestinal function can produce adverse findings in laboratory animals and humans and can negatively impact drug development. This review will discuss normal colon homeostasis with examples, where applicable, of xenobiotics that disrupt normal function. PMID:24129758

  20. Effects of morphine and naloxone on feline colonic transit

    SciTech Connect

    Krevsky, B.; Libster, B.; Maurer, A.H.; Chase, B.J.; Fisher, R.S.

    1989-01-01

    The effects of endogenous and exogenous opioid substances on feline colonic transit were evaluated using colonic transit scintigraphy. Naloxone accelerated emptying of the cecum and ascending colon, and filling of the transverse colon. Endogenous opioid peptides thus appear to play a significant role in the regulation of colonic transit. At a moderate dose of morphine cecum and ascending colon transit was accelerated, while at a larger dose morphine had no effect. Since naloxone, a relatively nonspecific opioid antagonist, and morphine, a principally mu opioid receptor agonist, both accelerate proximal colonic transit, a decelerating role for at least one of the other opioid receptors is inferred.

  1. Ageing and gastrointestinal sensory function: altered colonic mechanosensory and chemosensory function in the aged mouse

    PubMed Central

    Keating, Christopher; Nocchi, Linda; Yu, Yang; Donovan, Jemma; Grundy, David

    2016-01-01

    Key points Remarkably little is known about how age affects the sensory signalling pathways in the gastrointestinal tract despite age‐related gastrointestinal dysfunction being a prime cause of morbidity amongst the elderly populationHigh‐threshold gastrointestinal sensory nerves play a key role in signalling distressing information from the gut to the brain.We found that ageing is associated with attenuated high‐threshold afferent mechanosensitivity in the murine colon, and associated loss of TRPV1 channel function.These units have the capacity to sensitise in response to injurious events, and their loss in ageing may predispose the elderly to lower awareness of GI injury or disease. Abstract Ageing has a profound effect upon gastrointestinal function through mechanisms that are poorly understood. Here we investigated the effect of age upon gastrointestinal sensory signalling pathways in order to address the mechanisms underlying these changes. In vitro mouse colonic and jejunal preparations with attached splanchnic and mesenteric nerves were used to study mechanosensory and chemosensory afferent function in 3‐, 12‐ and 24‐month‐old C57BL/6 animals. Quantitative RT‐PCR was used to investigate mRNA expression in colonic tissue and dorsal root ganglion (DRG) cells isolated from 3‐ and 24‐month animals, and immunohistochemistry was used to quantify the number of 5‐HT‐expressing enterochromaffin (EC) cells. Colonic and jejunal afferent mechanosensory function was attenuated with age and these effects appeared earlier in the colon compared to the jejunum. Colonic age‐related loss of mechanosensory function was more pronounced in high‐threshold afferents compared to low‐threshold afferents. Chemosensory function was attenuated in the 24‐month colon, affecting TRPV1 and serotonergic signalling pathways. High‐threshold mechanosensory afferent fibres and small‐diameter DRG neurons possessed lower functional TRPV1 receptor responses

  2. Is there an efficient trap or collection method for sampling Anopheles darlingi and other malaria vectors that can describe the essential parameters affecting transmission dynamics as effectively as human landing catches? - A Review

    PubMed Central

    Lima, José Bento Pereira; Rosa-Freitas, Maria Goreti; Rodovalho, Cynara Melo; Santos, Fátima; Lourenço-de-Oliveira, Ricardo

    2014-01-01

    Distribution, abundance, feeding behaviour, host preference, parity status and human-biting and infection rates are among the medical entomological parameters evaluated when determining the vector capacity of mosquito species. To evaluate these parameters, mosquitoes must be collected using an appropriate method. Malaria is primarily transmitted by anthropophilic and synanthropic anophelines. Thus, collection methods must result in the identification of the anthropophilic species and efficiently evaluate the parameters involved in malaria transmission dynamics. Consequently, human landing catches would be the most appropriate method if not for their inherent risk. The choice of alternative anopheline collection methods, such as traps, must consider their effectiveness in reproducing the efficiency of human attraction. Collection methods lure mosquitoes by using a mixture of olfactory, visual and thermal cues. Here, we reviewed, classified and compared the efficiency of anopheline collection methods, with an emphasis on Neotropical anthropophilic species, especially Anopheles darlingi, in distinct malaria epidemiological conditions in Brazil. PMID:25185008

  3. Patients with chronic obstructive pulmonary disease and chronically colonized with Haemophilus influenzae during stable disease phase have increased airway inflammation

    PubMed Central

    Tufvesson, Ellen; Bjermer, Leif; Ekberg, Marie

    2015-01-01

    Background Some patients with chronic obstructive pulmonary disease (COPD) show increased airway inflammation and bacterial colonization during stable phase. The aim of this study was to follow COPD patients and investigate chronic colonization with pathogenic bacteria during stable disease phase, and relate these findings to clinical parameters, inflammatory pattern, lung function, and exacerbations. Methods Forty-three patients with COPD were included while in a stable state and followed up monthly until exacerbation or for a maximum of 6 months. The patients completed the Clinical COPD Questionnaire and Medical Research Council dyspnea scale questionnaires, and exhaled breath condensate was collected, followed by spirometry, impulse oscillometry, and sputum induction. Results Ten patients were chronically colonized (ie, colonized at all visits) with Haemophilus influenzae during stable phase. These patients had higher sputum levels of leukotriene B4 (P<0.001), 8-isoprostane (P=0.002), myeloperoxidase activity (P=0.028), and interleukin-8 (P=0.02) during stable phase when compared with other patients. In addition, they had lower forced vital capacity (P=0.035) and reactance at 5 Hz (P=0.034), but there was no difference in forced expiratory volume in 1 second (FEV1), FEV1 % predicted, forced vital capacity % predicted, exhaled breath condensate biomarkers, C-reactive protein, or Clinical COPD Questionnaire and Medical Research Council dyspnea scale results. Three patients had intermittent colonization (colonized at only some visits) of H. influenzae during stable phase, and had lower levels of inflammatory biomarkers in sputum when compared with the chronically colonized patients. The difference in airway inflammation seen during stable phase in patients chronically colonized with H. influenzae was not observed during exacerbations. Conclusion Some COPD patients who were chronically colonized with H. influenzae during stable phase showed increased airway

  4. Type I Interferons Direct Gammaherpesvirus Host Colonization

    PubMed Central

    Tan, Cindy S. E.; Lawler, Clara; May, Janet S.; Belz, Gabrielle T.; Stevenson, Philip G.

    2016-01-01

    Gamma-herpesviruses colonise lymphocytes. Murid Herpesvirus-4 (MuHV-4) infects B cells via epithelial to myeloid to lymphoid transfer. This indirect route entails exposure to host defences, and type I interferons (IFN-I) limit infection while viral evasion promotes it. To understand how IFN-I and its evasion both control infection outcomes, we used Mx1-cre mice to tag floxed viral genomes in IFN-I responding cells. Epithelial-derived MuHV-4 showed low IFN-I exposure, and neither disrupting viral evasion nor blocking IFN-I signalling markedly affected acute viral replication in the lungs. Maximising IFN-I induction with poly(I:C) increased virus tagging in lung macrophages, but the tagged virus spread poorly. Lymphoid-derived MuHV-4 showed contrastingly high IFN-I exposure. This occurred mainly in B cells. IFN-I induction increased tagging without reducing viral loads; disrupting viral evasion caused marked attenuation; and blocking IFN-I signalling opened up new lytic spread between macrophages. Thus, the impact of IFN-I on viral replication was strongly cell type-dependent: epithelial infection induced little response; IFN-I largely suppressed macrophage infection; and viral evasion allowed passage through B cells despite IFN-I responses. As a result, IFN-I and its evasion promoted a switch in infection from acutely lytic in myeloid cells to chronically latent in B cells. Murine cytomegalovirus also showed a capacity to pass through IFN-I-responding cells, arguing that this is a core feature of herpesvirus host colonization. PMID:27223694

  5. Type I Interferons Direct Gammaherpesvirus Host Colonization.

    PubMed

    Tan, Cindy S E; Lawler, Clara; May, Janet S; Belz, Gabrielle T; Stevenson, Philip G

    2016-05-01

    Gamma-herpesviruses colonise lymphocytes. Murid Herpesvirus-4 (MuHV-4) infects B cells via epithelial to myeloid to lymphoid transfer. This indirect route entails exposure to host defences, and type I interferons (IFN-I) limit infection while viral evasion promotes it. To understand how IFN-I and its evasion both control infection outcomes, we used Mx1-cre mice to tag floxed viral genomes in IFN-I responding cells. Epithelial-derived MuHV-4 showed low IFN-I exposure, and neither disrupting viral evasion nor blocking IFN-I signalling markedly affected acute viral replication in the lungs. Maximising IFN-I induction with poly(I:C) increased virus tagging in lung macrophages, but the tagged virus spread poorly. Lymphoid-derived MuHV-4 showed contrastingly high IFN-I exposure. This occurred mainly in B cells. IFN-I induction increased tagging without reducing viral loads; disrupting viral evasion caused marked attenuation; and blocking IFN-I signalling opened up new lytic spread between macrophages. Thus, the impact of IFN-I on viral replication was strongly cell type-dependent: epithelial infection induced little response; IFN-I largely suppressed macrophage infection; and viral evasion allowed passage through B cells despite IFN-I responses. As a result, IFN-I and its evasion promoted a switch in infection from acutely lytic in myeloid cells to chronically latent in B cells. Murine cytomegalovirus also showed a capacity to pass through IFN-I-responding cells, arguing that this is a core feature of herpesvirus host colonization. PMID:27223694

  6. N-Acylethanolamine-hydrolyzing acid amidase inhibition increases colon N-palmitoylethanolamine levels and counteracts murine colitis

    PubMed Central

    Alhouayek, Mireille; Bottemanne, Pauline; Subramanian, Kumar V.; Lambert, Didier M.; Makriyannis, Alexandros; Cani, Patrice D.; Muccioli, Giulio G.

    2015-01-01

    N-Palmitoylethanolamine or palmitoylethanolamide (PEA) is an anti-inflammatory compound that was recently shown to exert peroxisome proliferator-activated receptor-α-dependent beneficial effects on colon inflammation. The actions of PEA are terminated following hydrolysis by 2 enzymes: fatty acid amide hydrolase (FAAH), and the less-studied N-acylethanolamine-hydrolyzing acid amidase (NAAA). This study aims to investigate the effects of inhibiting the enzymes responsible for PEA hydrolysis in colon inflammation in order to propose a potential therapeutic target for inflammatory bowel diseases (IBDs). Two murine models of IBD were used to assess the effects of NAAA inhibition, FAAH inhibition, and PEA on macroscopic signs of colon inflammation, macrophage/neutrophil infiltration, and the expression of proinflammatory mediators in the colon, as well as on the colitis-related systemic inflammation. NAAA inhibition increases PEA levels in the colon and reduces colon inflammation and systemic inflammation, similarly to PEA. FAAH inhibition, however, does not increase PEA levels in the colon and does not affect the macroscopic signs of colon inflammation or immune cell infiltration. This is the first report of an anti-inflammatory effect of a systemically administered NAAA inhibitor. Because NAAA is the enzyme responsible for the control of PEA levels in the colon, we put forth this enzyme as a potential therapeutic target in chronic inflammation in general and IBD in particular.—Alhouayek, M., Bottemanne, P., Subramanian, K. V., Lambert, D. M., Makriyannis, A., Cani, P. D., and Muccioli, G. G. N-Acylethanolamine-hydrolyzing acid amidase inhibition increases colon N-palmitoylethanolamine levels and counteracts murine colitis. PMID:25384424

  7. Laparoscopic colon surgery: past, present and future.

    PubMed

    Martel, Guillaume; Boushey, Robin P

    2006-08-01

    Since its first described case in 1991, laparoscopic colon surgery has lagged behind minimally invasive surgical methods for solid intra-abdominal organs in terms of acceptability, dissemination, and ease of learning. In colon cancer, initial concerns over port site metastases and adequacy of oncologic resection have considerably dampened early enthusiasm for this procedure. Only recently, with the publication of several large, randomized controlled trials, has the incidence of port site metastases been shown to be equivalent to that of open resection. Laparoscopic surgery for colon cancer has also been demonstrated to be at least equivalent to traditional laparotomy in terms of adequacy of oncologic resection, disease recurrence, and long-term survival. In addition, numerous reports have validated short-term benefits following laparoscopic resection for cancer, including shorter hospital stay, shorter time to recovery of bowel function, and decreased analgesic requirements, as well as other postoperative variables. In benign colonic disease, much less high-quality literature exists supporting the use of laparoscopic methods. Two recent randomized controlled trials have demonstrated some short-term benefits to laparoscopic ileocolic resection for CD, in addition to evident cosmetic advantages. On the other hand, the current evidence on laparoscopic surgery for UC does not support its routine use among nonexpert surgeons outside of specialized centers. Laparoscopic colonic resection for diverticular disease appears to provide several short-term benefits, although these advantages may not translate to cases of complicated diverticulitis. Despite the increasing acceptability of minimally invasive methods for the management of benign and malignant colonic pathologies, laparoscopic colon resection remains a prohibitively difficult technique to master. Numerous technological innovations have been introduced onto the market in an effort to decrease the steep learning

  8. Elements affecting runway traction

    NASA Technical Reports Server (NTRS)

    Horne, W. B.

    1974-01-01

    The five basic elements affecting runway traction for jet transport aircraft operation are identified and described in terms of pilot, aircraft system, atmospheric, tire, and pavement performance factors or parameters. Where possible, research results are summarized, and means for restoring or improving runway traction for these different conditions are discussed.

  9. The cure for colon cancer: results from the EUROCARE study.

    PubMed

    Verdecchia, A; De Angelis, R; Capocaccia, R; Sant, M; Micheli, A; Gatta, G; Berrino, F

    1998-07-29

    The interpretation of time trends and geographical differences of population-based survival rates is generally not easy, due to the difficulty in disentangling the effects of observational biases, diagnostic and therapeutic procedures and their interactions. Whereas descriptive analysis of relative survival is generally based on survival levels estimated at fixed time since diagnosis, interpretation issues can take advantage from the analysis of the shape of the considered relative survival. Parametric survival models allowing the estimation of the fraction of cured patients are applied here to analyze and discuss the differences in colon cancer relative survival between European countries, according to age and period of diagnosis. The survival curves of colon cancer patients are described according to 2 parameters: the proportion of cured patients and the mean survival time of fatal cases. These parameters are estimated by least square nonlinear regression of relative survival values derived from the EUROCARE Project publication. Exponential and Weibull survival functions are used to model the relative survival curve for the fraction of fatal cases. The Weibull model gives generally a better fit with respect to the exponential model, thus indicating that the mortality rate for fatal cases is decreasing with time since diagnosis. For the youngest patients, however, the 2 survival functions give practically overlapping estimates. The overall proportion of colon cancer patients in Europe that are estimated to be cured was 38.6%. This proportion increased from 36% to 40% for patients diagnosed in 1978-1980 and in 1983-1985, respectively. Accordingly, mean survival time of fatal cases increased from 1.18 to 1.52 years. According to age, the proportion of cured patients present a marked decrease from young (48.4% at age 15-44 years) to middle-aged patients (38.6% at age 5564 years) and only a mild decrease from these to the oldest patients (34.4% at age 75 or more). The

  10. Colon centerline extraction in fragmented segmentations.

    PubMed

    Krishnan, Karthik; Madrosiya, Akshay; Desai, Nasir

    2015-08-01

    In virtual colonoscopy, the clinical need is a smooth centered path from the rectum to the cecum, for interactive navigation along the colonic lumen. The primary challenge is breakages in the colon, due to fecal residue, abnormalities, poor insufflation and inadequate electronic cleansing. Here we propose a method, that is a modification of the classic energy minimized geodesic, that extracts centered paths through fragmented colons. To begin, we perform electronic cleansing, automatically localize 4 points: rectum, cecum, sphlenic and hepatic flexures; followed by region growing and heuristic approaches to generate the initial segmentation. This is followed by a daisy chaining procedure to link possibly large colon blobs that may have been missed as weaker candidate segmentations. We then perform a front propagation to extract a minimal energy path through the ordered set of points. This propagation is guided by multiple forces: (a) A strong force given by the distance to the colon segmentation surface (b) A weak force derived from the CT intensity (c) A weak force from the distance to the surface of weaker candidate colon segmentations (d) A geodesic repulsive force, where the other points exhibit an repelling force in their voronoi partition, the force proportional to the geodesic distance to the point. Our contribution is a path extraction method for the colon that is the energy minimized geodesic (a) favouring centeredness (b) punching through gaps, traversing in so far as possible through lower intensity regions and possibly centered within these gaps (c) ordered through the feature points. Results show improvements of the method over the standard minimal energy path approach. PMID:26736927

  11. Colonic Patch and colonic SILT development are independent and differentially-regulated events

    PubMed Central

    Baptista, AP; Olivier, BJ; Goverse, G; Greuter, M; Knippenberg, M; Kusser, K; Domingues, RG.; Veiga-Fernandes, H; Luster, AD; Lugering, A; Randall, TD; Cupedo, T; Mebius, RE

    2012-01-01

    Intestinal lymphoid tissues have to simultaneously ensure protection against pathogens and tolerance towards commensals. Despite such vital functions, their development in the colon is poorly understood. Here, we show that the two distinct lymphoid tissues of the colon–colonic patches and colonic SILTs–can easily be distinguished based on anatomical location, developmental timeframe and cellular organization. Furthermore, whereas colonic patch development depended on CXCL13-mediated LTi cell clustering followed by LTα-mediated consolidation, early LTi clustering at SILT anlagen did not require CXCL13, CCR6 or CXCR3. Subsequent dendritic cell recruitment to and gp38+VCAM-1+ lymphoid stromal cell differentiation within SILTs required LTα; B cell recruitment and follicular dendritic cell differentiation depended on MyD88-mediated signalling, but not the microflora. In conclusion, our data demonstrate that different mechanisms, mediated mainly by programmed stimuli, induce the formation of distinct colonic lymphoid tissues, therefore suggesting that these tissues may have different functions. PMID:22990625

  12. Supergranular Parameters

    NASA Astrophysics Data System (ADS)

    Udayashankar, Paniveni

    2016-07-01

    I study the complexity of supergranular cells using intensity patterns from Kodaikanal solar observatory. The chaotic and turbulent aspect of the solar supergranulation can be studied by examining the interrelationships amongst the parameters characterizing supergranular cells namely size, horizontal flow field, lifetime and physical dimensions of the cells and the fractal dimension deduced from the size data. The findings are supportive of Kolmogorov's theory of turbulence. The Data consists of visually identified supergranular cells, from which a fractal dimension 'D' for supergranulation is obtained according to the relation P α AD/2 where 'A' is the area and 'P' is the perimeter of the supergranular cells. I find a fractal dimension close to about 1.3 which is consistent with that for isobars and suggests a possible turbulent origin. The cell circularity shows a dependence on the perimeter with a peak around (1.1-1.2) x 105 m. The findings are supportive of Kolmogorov's theory of turbulence.

  13. Clinical and Economic Evaluation of Multidrug-Resistant Acinetobacter baumannii Colonization in the Intensive Care Unit

    PubMed Central

    2016-01-01

    Background The clinical and economic impact of multidrug-resistant (MDR) Acinetobacter baumannii colonization remains unclear. This study aimed to estimate and compare the mortality rates, length of stay (LOS), and hospitalization costs in the intensive care unit (ICU) for MDR A. baumannii colonized patients and a matched population. Materials and Methods We performed a retrospective propensity score matched cohort study comparing the outcomes of patients with MDR A. baumannii colonization with those of uncolonized subjects matched at the time they were admitted to the ICU between January 2012 and December 2014. Results During the study period, 375 (7.5%) of the 4,779 patients were colonized with MDR A. baumannii. One hundred and twenty-two MDR A. baumannii colonized patients were compared with 122 uncolonized patients using propensity score matching. MDR A. baumannii colonized patients were likely to have a higher mortality rate compared to uncolonized patients (49.2% vs 32.0%; odds ratio [OR], 3.64). A longer ICU LOS and total admission days were observed in the MDR A. baumannii colonized patient group (4.14 and 4.67 days increase, OR 1.41 and 1.19). MDR A. baumannii colonization patients had an average extra ICU and total admission cost of $1,179 (₩1,261,334) and $1,333 (₩1,422,032) according to a multivariable regression model (OR, 1.27 and 1.17). Multivariable analysis identified the factors affecting ICU cost, which included, MDR A. baumannii colonization (OR = 1.33; P = 0.001), ICU LOS (OR = 1.97; P <0.001), valvular heart disease (OR = 1.12; P = 0.005), invasive devices (OR = 1.15; P = 0.018), and surgery (OR = 1.1; P <0.001). Conclusion MDR A. baumannii colonization was associated with increased mortality, LOS, and costs in the ICU. A strict infection control program including preemptive isolation for high-risk groups would be helpful for reducing the burden of this infection. PMID:27659440

  14. Differential expression of nanog1 and nanogp8 in colon cancer cells

    SciTech Connect

    Ishiguro, Tatsuya; Sato, Ai; Ohata, Hirokazu; Sakai, Hiroaki; Nakagama, Hitoshi; Okamoto, Koji

    2012-02-10

    Highlights: Black-Right-Pointing-Pointer Nanog is expressed in a majority of colon cancer cell lines examined. Black-Right-Pointing-Pointer Both nanog1 and nanogp8 are expressed in colon cancer cells with varying ratios. Black-Right-Pointing-Pointer Nanog mediates cell proliferation of colon cancer cells. Black-Right-Pointing-Pointer Nanog predominantly localizes in cytoplasm of colon cancer cells. -- Abstract: Nanog, a homeodomain transcription factor, is an essential regulator for promotion of self-renewal of embryonic stem cells and inhibition of their differentiation. It has been demonstrated that nanog1 as well as nanogp8, a retrogene of nanog1, is preferentially expressed in advanced stages of several types of cancer, suggesting their involvement during cancer progression. Here, we investigated the expression of Nanog in well-characterized colon cancer cell lines. Expression of Nanog was detectable in 5 (HCT116, HT29, RKO, SW48, SW620) out of seven cell lines examined. RNA expression analyses of nanog1 and nanogp8 indicated that, while nanog1 was a major form in SW620 as well as in teratoma cells Tera-2, nanogp8 was preferentially expressed in HT29 and HCT116. In accordance with this, shRNA-mediated knockdown of nanog1 caused the reduction of Nanog in SW620 but not in HT29. Inhibition of Nanog in SW620 cells negatively affected cell proliferation and tumor formation in mouse xenograft. Biochemical subcellular fractionation and immunostaining analyses revealed predominant localization of Nanog in cytoplasm in SW620 and HT29, while it was mainly localized in nucleus in Tera-2. Our data indicate that nanog1 and nanogp8 are differentially expressed in colon cancer cells, and suggest that their expression contributes to proliferation of colon cancer cells.

  15. Above-ground herbivory causes rapid and sustained changes in mycorrhizal colonization of grasses.

    PubMed

    Wearn, James A; Gange, Alan C

    2007-10-01

    Arbuscular mycorrhizal fungi (AMF) play a vital role in ecosystem functioning. In most grasslands, herbivory by both vertebrate and invertebrate herbivores is common and thus in order to assess herbivore effects on multitrophic-level interactions both should be considered. This study investigated the effects of grazing by rabbit and insect herbivores on root-colonization of grasses by AMF in two lowland grasslands in southern England, UK. A long-term exclosure site was used to provide a temporal assessment in order to elucidate whether any short-term responses to herbivore removal were sustained. Root samples from three grass species at each site were analysed in terms of total mycorrhizal colonization and proportional colonization by individual mycorrhizal structures. Colonization levels were up to 1.6 times greater under moderate levels of rabbit grazing (with summer maxima of 25% and winter minima of 11%) than in intensely grazed swards or fenced plots at both sites. The change was fast (within 8 weeks), consistent throughout the sampled field plots, and temporally sustainable over a 19-year period. There was no significant effect of insect herbivory on total colonization but proportional colonization by different AM structures was affected on some sample dates where vertebrate herbivores had been removed, indicating a slight effect on fungal structure allocation. The results suggest that the type of herbivore and perhaps more importantly the intensity of grazing are key determinants of below-ground effects upon mycorrhizal-host plant symbiosis. The data suggest that the extent of mycorrhizal colonization within grass host plants is strongly influenced by C assimilation and allocation.

  16. Transcriptional recapitulation and subversion of embryonic colon development by mouse colon tumor models and human colon cancer

    PubMed Central

    Kaiser, Sergio; Park, Young-Kyu; Franklin, Jeffrey L; Halberg, Richard B; Yu, Ming; Jessen, Walter J; Freudenberg, Johannes; Chen, Xiaodi; Haigis, Kevin; Jegga, Anil G; Kong, Sue; Sakthivel, Bhuvaneswari; Xu, Huan; Reichling, Timothy; Azhar, Mohammad; Boivin, Gregory P; Roberts, Reade B; Bissahoyo, Anika C; Gonzales, Fausto; Bloom, Greg C; Eschrich, Steven; Carter, Scott L; Aronow, Jeremy E; Kleimeyer, John; Kleimeyer, Michael; Ramaswamy, Vivek; Settle, Stephen H; Boone, Braden; Levy, Shawn; Graff, Jonathan M; Doetschman, Thomas; Groden, Joanna; Dove, William F; Threadgill, David W; Yeatman, Timothy J; Coffey, Robert J; Aronow, Bruce J

    2007-01-01

    Background The expression of carcino-embryonic antigen by colorectal cancer is an example of oncogenic activation of embryonic gene expression. Hypothesizing that oncogenesis-recapitulating-ontogenesis may represent a broad programmatic commitment, we compared gene expression patterns of human colorectal cancers (CRCs) and mouse colon tumor models to those of mouse colon development embryonic days 13.5-18.5. Results We report here that 39 colon tumors from four independent mouse models and 100 human CRCs encompassing all clinical stages shared a striking recapitulation of embryonic colon gene expression. Compared to normal adult colon, all mouse and human tumors over-expressed a large cluster of genes highly enriched for functional association to the control of cell cycle progression, proliferation, and migration, including those encoding MYC, AKT2, PLK1 and SPARC. Mouse tumors positive for nuclear β-catenin shifted the shared embryonic pattern to that of early development. Human and mouse tumors differed from normal embryonic colon by their loss of expression modules enriched for tumor suppressors (EDNRB, HSPE, KIT and LSP1). Human CRC adenocarcinomas lost an additional suppressor module (IGFBP4, MAP4K1, PDGFRA, STAB1 and WNT4). Many human tumor samples also gained expression of a coordinately regulated module associated with advanced malignancy (ABCC1, FOXO3A, LIF, PIK3R1, PRNP, TNC, TIMP3 and VEGF). Conclusion Cross-species, developmental, and multi-model gene expression patterning comparisons provide an integrated and versatile framework for definition of transcriptional programs associated with oncogenesis. This approach also provides a general method for identifying pattern-specific biomarkers and therapeutic targets. This delineation and categorization of developmental and non-developmental activator and suppressor gene modules can thus facilitate the formulation of sophisticated hypotheses to evaluate potential synergistic effects of targeting within- and

  17. Space Colonization-Benefits for the World

    NASA Astrophysics Data System (ADS)

    Siegfried, W. H.

    2003-01-01

    We have begun to colonize space, even to the extent of early space tourism. Our early Vostok, Mercury, Gemini, Apollo, Skylab, Spacehab, Mir and now ISS are humankind's first ventures toward colonization. Efforts are underway to provide short space tours, and endeavors such as the X-Prize are encouraging entrepreneurs to provide new systems. Many believe that extended space travel (colonization) will do for the 21st century what aviation did for the 20th. Our current concerns including terrorism, hunger, disease, and problems of air quality, safe abundant water, poverty, and weather vagaries tend to overshadow long-term activities such as Space Colonization in the minds of many. Our leading ``think tanks'' such as the Woodrow Wilson International Center for Scholars and the Brookings Institute do not rate space travel high on lists of future beneficial undertakings even though many of the concerns listed above are prominently featured. It is the contention of this paper that Space Colonization will lead toward solutions to many of the emerging problems of our Earth, both technological and sociological. The breadth of the enterprise far exceeds the scope of our normal single-purpose missions and, therefore, its benefits will be greater.

  18. Crater lake colonization by neotropical cichlid fishes.

    PubMed

    Elmer, Kathryn R; Lehtonen, Topi K; Fan, Shaohua; Meyer, Axel

    2013-01-01

    Volcanic crater lakes are isolated habitats that are particularly well suited to investigating ecological and evolutionary divergence and modes of speciation. However, the mode, frequency, and timing of colonization of crater lakes have been difficult to determine. We used a statistical comparative phylogeographic approach, based on a mitochondrialDNA dataset, to infer the colonization history of two Nicaraguan crater lakes by populations of genetically and ecologically divergent cichlid lineages: Midas (Amphilophus cf. citrinellus complex) and moga (Hypsophrys nematopus). We compared estimates of diversity among populations within the two cichlid lineages and found that Midas were the most genetically diverse. From an approximate Bayesian computation analysis, we inferred that the crater lakes were each founded by both cichlid lineages in single waves of colonization: Masaya 5800 ± 300 years ago and Xiloá 5400 ± 750 years ago. We conclude that natural events are likely to have a dominant role in colonization of the crater lakes. Further, our findings suggest that the higher species richness and more rapid evolution of the Midas species complex, relative to other lineages of fishes in the same crater lakes, cannot be explained by earlier or more numerous colonization events.

  19. Nuclear microscopy of rat colon epithelial cells

    NASA Astrophysics Data System (ADS)

    Ren, M.; Rajendran, Reshmi; Ng, Mary; Udalagama, Chammika; Rodrigues, Anna E.; Watt, Frank; Jenner, Andrew Michael

    2011-10-01

    Using Nuclear microscopy, we have investigated iron distributions in the colons of Sprague Dawley rats, in order to elucidate heme uptake. Four groups of five Sprague Dawley rats (mean weight 180 g) were fed different purified diets containing either heme diet (2.5% w/w hemoglobin), high fat diet (HFD) (18% w/w fat, 1% w/w cholesterol), 'western' diet (combination of hemoglobin 2.5% and 18% fat, 1% cholesterol) or control diet (7% w/w fat). After 4 weeks, animals were sacrificed by exsanguination after anaesthesia. Thin sections of frozen colon tissue were taken, freeze dried and scanned using nuclear microscopy utilising the techniques PIXE, RBS and STIM. The new data acquisition system (IonDaq) developed in CIBA was used to obtain high resolution images and line scans were used to map the iron distributions across the colon boundaries. The nuclear microscope results indicate that when HFD is given in addition to heme, the iron content of the epithelial cells that line the colon decreases, and the zinc in the smooth muscle wall increases. This implies that the level of heme and fat in diet has an important role in colon health, possibly by influencing epithelial cells directly or changing luminal composition such as bacterial flora or levels of metabolites and cytotoxins.

  20. Chemopreventive effect of the non-psychotropic phytocannabinoid cannabidiol on experimental colon cancer.

    PubMed

    Aviello, Gabriella; Romano, Barbara; Borrelli, Francesca; Capasso, Raffaele; Gallo, Laura; Piscitelli, Fabiana; Di Marzo, Vincenzo; Izzo, Angelo A

    2012-08-01

    Colon cancer affects millions of individuals in Western countries. Cannabidiol, a safe and non-psychotropic ingredient of Cannabis sativa, exerts pharmacological actions (antioxidant and intestinal antinflammatory) and mechanisms (inhibition of endocannabinoid enzymatic degradation) potentially beneficial for colon carcinogenesis. Thus, we investigated its possible chemopreventive effect in the model of colon cancer induced by azoxymethane (AOM) in mice. AOM treatment was associated with aberrant crypt foci (ACF, preneoplastic lesions), polyps, and tumour formation, up-regulation of phospho-Akt, iNOS and COX-2 and down-regulation of caspase-3. Cannabidiol-reduced ACF, polyps and tumours and counteracted AOM-induced phospho-Akt and caspase-3 changes. In colorectal carcinoma cell lines, cannabidiol protected DNA from oxidative damage, increased endocannabinoid levels and reduced cell proliferation in a CB(1)-, TRPV1- and PPARγ-antagonists sensitive manner. It is concluded that cannabidiol exerts chemopreventive effect in vivo and reduces cell proliferation through multiple mechanisms.

  1. Effects of airborne particulate matter on alternative pre-mRNA splicing in colon cancer cells.

    PubMed

    Buggiano, Valeria; Petrillo, Ezequiel; Alló, Mariano; Lafaille, Celina; Redal, María Ana; Alghamdi, Mansour A; Khoder, Mamdouh I; Shamy, Magdy; Muñoz, Manuel J; Kornblihtt, Alberto R

    2015-07-01

    Alternative pre-mRNA splicing plays key roles in determining tissue- and species-specific cell differentiation as well as in the onset of hereditary disease and cancer, being controlled by multiple post- and co-transcriptional regulatory mechanisms. We report here that airborne particulate matter, resulting from industrial pollution, inhibits expression and specifically affects alternative splicing at the 5' untranslated region of the mRNA encoding the bone morphogenetic protein BMP4 in human colon cells in culture. These effects are consistent with a previously reported role for BMP4 in preventing colon cancer development, suggesting that ingestion of particulate matter could contribute to the onset of colon cell proliferation. We also show that the underlying mechanism might involve changes in transcriptional elongation. This is the first study to demonstrate that particulate matter causes non-pleiotropic changes in alternative splicing.

  2. Quantitative contribution of factors regulating rat colonic crypt epithelium: role of parenteral and enteral feeding, caloric intake, dietary cellulose level and the colon carcinogen DMH.

    PubMed

    Cameron, I L; Ord, V A; Hunter, K E; Van Nguyen, M; Padilla, G M; Heitman, D W

    1990-05-01

    To elucidate the role and quantitative contribution of several exogenous factors which may regulate colon crypt mitotic activity, proliferative zone height (PZH) and crypt height, groups of rats were subjected to various feeding regimens both with and without treatment with the colon carcinogen, 1,2-dimethylhydrazine (DMH). The rats were divided into two major groups and one group was given eight weekly injections of DMH base at 9.5 mg kg-1 body weight. Throughout this period and for two additional weeks the rats were isocalorically fed either a defined nutritionally complete diet with different levels of dietary cellulose or they were parenterally (i.v.) fed a nutritionally complete liquid formula with different caloric levels. The rats were then injected with colchicine 3 h prior to sacrifice to arrest and to collect dividing cells at metaphase. The results of multiple regression analysis of all data were interpreted to indicate that parenteral feeding caused dramatic suppression of the colon crypt height (CH) and of the number of metaphase figures per crypt (MC). Increased cellulose intake stimulated CH but suppressed MC. The CH was also stimulated by DMH. CH was positively correlated to PZH and MC. The MC was suppressed by cellulose intake and negatively correlated to PZH but was positively correlated to CH. The PZH was positively correlated to CH. These findings were related to the role of luminal food, functional workload, kcal intake and treatment with DMH on the measured colon crypt parameters. A quantitative assessment of factors that regulate the measured colonic crypt parameters was accomplished.

  3. Affective responses to dance.

    PubMed

    Christensen, Julia F; Pollick, Frank E; Lambrechts, Anna; Gomila, Antoni

    2016-07-01

    The objective of the present work was the characterization of mechanisms by which affective experiences are elicited in observers when watching dance movements. A total of 203 dance stimuli from a normed stimuli library were used in a series of independent experiments. The following measures were obtained: (i) subjective measures of 97 dance-naïve participants' affective responses (Likert scale ratings, interviews); and (ii) objective measures of the physical parameters of the stimuli (motion energy, luminance), and of the movements represented in the stimuli (roundedness, impressiveness). Results showed that (i) participants' ratings of felt and perceived affect differed, (ii) felt and perceived valence but not arousal ratings correlated with physical parameters of the stimuli (motion energy and luminance), (iii) roundedness in posture shape was related to the experience of more positive emotion than edgy shapes (1 of 3 assessed rounded shapes showed a clear effect on positiveness ratings while a second reached trend level significance), (iv) more impressive movements resulted in more positive affective responses, (v) dance triggered affective experiences through the imagery and autobiographical memories it elicited in some people, and (vi) the physical parameters of the video stimuli correlated only weakly and negatively with the aesthetics ratings of beauty, liking and interest. The novelty of the present approach was twofold; (i) the assessment of multiple affect-inducing mechanisms, and (ii) the use of one single normed stimulus set. The results from this approach lend support to both previous and present findings. Results are discussed with regards to current literature in the field of empirical aesthetics and affective neuroscience.

  4. Affective responses to dance.

    PubMed

    Christensen, Julia F; Pollick, Frank E; Lambrechts, Anna; Gomila, Antoni

    2016-07-01

    The objective of the present work was the characterization of mechanisms by which affective experiences are elicited in observers when watching dance movements. A total of 203 dance stimuli from a normed stimuli library were used in a series of independent experiments. The following measures were obtained: (i) subjective measures of 97 dance-naïve participants' affective responses (Likert scale ratings, interviews); and (ii) objective measures of the physical parameters of the stimuli (motion energy, luminance), and of the movements represented in the stimuli (roundedness, impressiveness). Results showed that (i) participants' ratings of felt and perceived affect differed, (ii) felt and perceived valence but not arousal ratings correlated with physical parameters of the stimuli (motion energy and luminance), (iii) roundedness in posture shape was related to the experience of more positive emotion than edgy shapes (1 of 3 assessed rounded shapes showed a clear effect on positiveness ratings while a second reached trend level significance), (iv) more impressive movements resulted in more positive affective responses, (v) dance triggered affective experiences through the imagery and autobiographical memories it elicited in some people, and (vi) the physical parameters of the video stimuli correlated only weakly and negatively with the aesthetics ratings of beauty, liking and interest. The novelty of the present approach was twofold; (i) the assessment of multiple affect-inducing mechanisms, and (ii) the use of one single normed stimulus set. The results from this approach lend support to both previous and present findings. Results are discussed with regards to current literature in the field of empirical aesthetics and affective neuroscience. PMID:27235953

  5. Lactose malabsorption and colonic fermentations alter host metabolism in rats.

    PubMed

    Alexandre, Virginie; Even, Patrick C; Larue-Achagiotis, Christiane; Blouin, Jean-Marc; Blachier, François; Benamouzig, Robert; Tomé, Daniel; Davila, Anne-Marie

    2013-08-01

    Lactose malabsorption is associated with rapid production of high levels of osmotic compounds, such as organic acids and SCFA in the colon, suspected to contribute to the onset of lactose intolerance. Adult rats are lactase deficient and the present study was conducted to evaluate in vivo the metabolic consequences of acute lactose ingestion, including host-microbiota interactions. Rats received diets of 25% sucrose (S25 control group) or 25% lactose (L25 experimental group). SCFA and lactic acid were quantified in intestinal contents and portal blood. Expression of SCFA transporter genes was quantified in the colonic mucosa. Carbohydrate oxidation (Cox) and lipid oxidation (Lox) were computed by indirect calorimetry. Measurements were performed over a maximum of 13 h. Time, diet and time × diet variables had significant effects on SCFA concentration in the caecum (P<0·001, P=0·004 and P=0·007, respectively) and the portal blood (P<0·001, P=0·04 and P<0·001, respectively). Concomitantly, expression of sodium monocarboxylate significantly increased in the colonic mucosa of the L25 group (P=0·003 at t = 6 h and P<0·05 at t = 8 h). During 5 h after the meal, the L25 group's changes in metabolic parameters (Cox, Lox) were significantly lower than those of the S25 group (P=0·02). However, after 5 h, L25 Cox became greater than S25 (P=0·004). Thus, enhanced production and absorption of SCFA support the metabolic changes observed in calorimetry. These results underline the consequences of acute lactose malabsorption and measured compensations occurring in the host's metabolism, presumably through the microbiota fermentations and microbiota-host interactions.

  6. PET-MRI in Diagnosing Patients With Colon or Rectal Cancer

    ClinicalTrials.gov

    2015-11-25

    Recurrent Colon Cancer; Recurrent Rectal Cancer; Stage IIA Colon Cancer; Stage IIA Rectal Cancer; Stage IIB Colon Cancer; Stage IIB Rectal Cancer; Stage IIC Colon Cancer; Stage IIC Rectal Cancer; Stage IIIA Colon Cancer; Stage IIIA Rectal Cancer; Stage IIIB Colon Cancer; Stage IIIB Rectal Cancer; Stage IIIC Colon Cancer; Stage IIIC Rectal Cancer; Stage IVA Colon Cancer; Stage IVA Rectal Cancer; Stage IVB Colon Cancer; Stage IVB Rectal Cancer

  7. Antiproliferative and proapoptotic effects of viable or heat-killed Lactobacillus paracasei IMPC2.1 and Lactobacillus rhamnosus GG in HGC-27 gastric and DLD-1 colon cell lines.

    PubMed

    Orlando, A; Refolo, M G; Messa, C; Amati, L; Lavermicocca, P; Guerra, V; Russo, F

    2012-01-01

    Data from literature suggest the possible use of probiotics as chemopreventive agents against colon cancer, but few investigations are available on their effects on gastric cancer proliferation. In our previous study, a specific Lactobacillus, strain L. paracasei IMPC2.1, was demonstrated to colonize the human gut and positively affect fecal bacteria and biochemical parameters. The aims of the present study were to investigate the effects of L. paracasei IMPC2.1, comparing them with those of Lactobacillus rhamnosus GG (L.GG), either as viable or heat-killed cells, on cell proliferation and apoptosis in a gastric cancer (HGC-27) and a colorectal cancer cell line (DLD-1). Both the gastric and colon cancer cells were sensitive to the growth inhibition and apoptosis induction by both viable or heat-killed cells from L. paracasei IMPC2.1 and L.GG. These findings suggest the possibility for a food supplement, based on dead probiotics, including L. paracasei IMPC2.1 cells, which could represent an effective component of a functional food strategy for cancer growth inhibition, with potential for cancer prevention. PMID:23061912

  8. Lack of CD24 expression in mice reduces the number of leukocytes in the colon.

    PubMed

    Bretz, Niko P; Salnikov, Alexei V; Doberstein, Kai; Garbi, Natalio; Kloess, Volker; Joumaa, Safwan; Naumov, Inna; Boon, Louis; Moldenhauer, Gerhard; Arber, Nadir; Altevogt, Peter

    2014-09-01

    CD24 is an extensively glycosylated membrane protein that is linked to the membrane via a glycosyl-phosphatidylinositol (GPI)-anchor. In mice, CD24 is expressed by hematopoietic and non-hematopoietic cells. CD24-/- mice do not have gross immunological defects, but detailed analysis revealed strongly reduced responses in an experimental autoimmune encephalomyelitis (EAE) model and a massive proliferation of T cells under lymphopenic conditions. It was also demonstrated that preB cells from CD24-/- mice are impaired in α4-integrin-mediated cell binding. Here we report that CD24-/- mice have strongly reduced numbers of leukocytes in the colon compared to wildtype mice. The reduction comprized all subpopulations. Leukocyte counts in spleen, mesenteric lymph nodes or small intestine were not significantly different. We find that beside leukocytes, CD24 is widely expressed in EpCAM+ epithelial and CD31+ endothelial cells of colon and small intestine. However, in CD24-/- mice the number of CD31+ endothelial cells in colons was strongly reduced and the number of epithelial cells was augmented. Leukocyte transfer experiments provided evidence that the CD24 status of recipient mice, rather than of the transferred cells, is crucial for leukocyte recruitment to the colon. We hypothesize that CD24 on colonic epithelial and endothelial cells is required for the retention and positioning of leukocytes most likely by affecting integrin function.

  9. Securing the demographic and genetic future of tuatara through assisted colonization.

    PubMed

    Miller, Kimberly A; Miller, Hilary C; Moore, Jennifer A; Mitchell, Nicola J; Cree, Alison; Allendorf, Fred W; Sarre, Stephen D; Keall, Susan N; Nelson, Nicola J

    2012-10-01

    Climate change poses a particular threat to species with fragmented distributions and little or no capacity to migrate. Assisted colonization, moving species into regions where they have not previously occurred, aims to establish populations where they are expected to survive as climatic envelopes shift. However, adaptation to the source environment may affect whether species successfully establish in new regions. Assisted colonization has spurred debate among conservation biologists and ecologists over whether the potential benefits to the threatened species outweigh the potential disruption to recipient communities. In our opinion, the debate has been distracted by controversial examples, rather than cases where assisted colonization may be a viable strategy. We present a strategic plan for the assisted migration of tuatara (Sphenodon punctatus), an endemic New Zealand reptile. The plan includes use of extant populations as reference points for comparisons with assisted-colonization populations with respect to demography, phenotypic plasticity, and phenology; optimization of genetic variation; research to fill knowledge gaps; consideration of host and recipient communities; and inclusion of stakeholders in the planning stage. When strategically planned and monitored, assisted colonization could meet conservation and research goals and ultimately result in the establishment of long-term sustainable populations capable of persisting during rapid changes in climate. PMID:22827440

  10. The dipeptidyl peptidase-4 inhibitor sitagliptin suppresses mouse colon tumorigenesis in type 2 diabetic mice.

    PubMed

    Yorifuji, Naoki; Inoue, Takuya; Iguchi, Munetaka; Fujiwara, Kaori; Kakimoto, Kazuki; Nouda, Sadaharu; Okada, Toshihiko; Kawakami, Ken; Abe, Yosuke; Takeuchi, Toshihisa; Higuchi, Kazuhide

    2016-02-01

    Patients with type 2 diabetes mellitus are known to have an increased risk of colorectal neoplasia. Dipeptidyl peptidase-4 (DPP-4) inhibitors have been used as a new therapeutic tool for type 2 diabetes. Since the substrates for DPP-4 include intestinotrophic hormones and chemokines such as GLP-2 and stromal cell-derived factor-1 (SDF-1), which are associated with tumor progression, DPP-4 inhibitors may increase the risk of colorectal tumors. However, the influence of DPP-4 inhibitors on colorectal neoplasia in patients with type 2 diabetes remains unknown. In the present study, we show that long-term administration of a DPP-4 inhibitor, sitagliptin (STG), suppressed colon carcinogenesis in leptin-deficient (ob/ob) C57BL/6J mice. Colonic mucosal concentrations of glucagon‑like peptide-1 (GLP-1) and GLP-2 were significantly elevated in the ob/ob mice. However, mucosal GLP concentrations and the plasma level of SDF-1 were not affected by the administration of STG. Real‑time PCR analysis revealed that colonic mucosal IL-6 mRNA expression, which was significantly upregulated in the ob/ob mice, was significantly suppressed by the long-term administration of STG. These results suggest that a DPP-4 inhibitor may suppress colon carcinogenesis in mice with type 2 diabetes in a GLP-independent manner. Since DPP-4 has multiple biological functions, further studies analyzing other factors related to colon carcinogenesis are needed.

  11. Integrating Multiple Analytical Datasets to Compare Metabolite Profiles of Mouse Colonic-Cecal Contents and Feces

    PubMed Central

    Zeng, Huawei; Grapov, Dmitry; Jackson, Matthew I.; Fahrmann, Johannes; Fiehn, Oliver; Combs, Gerald F.

    2015-01-01

    The pattern of metabolites produced by the gut microbiome comprises a phenotype indicative of the means by which that microbiome affects the gut. We characterized that phenotype in mice by conducting metabolomic analyses of the colonic-cecal contents, comparing that to the metabolite patterns of feces in order to determine the suitability of fecal specimens as proxies for assessing the metabolic impact of the gut microbiome. We detected a total of 270 low molecular weight metabolites in colonic-cecal contents and feces by gas chromatograph, time-of-flight mass spectrometry (GC-TOF) and ultra-high performance liquid chromatography, quadrapole time-of-flight mass spectrometry (UPLC-Q-TOF). Of that number, 251 (93%) were present in both types of specimen, representing almost all known biochemical pathways related to the amino acid, carbohydrate, energy, lipid, membrane transport, nucleotide, genetic information processing, and cancer-related metabolism. A total of 115 metabolites differed significantly in relative abundance between both colonic-cecal contents and feces. These data comprise the first characterization of relationships among metabolites present in the colonic-cecal contents and feces in a healthy mouse model, and shows that feces can be a useful proxy for assessing the pattern of metabolites to which the colonic mucosum is exposed. PMID:26378591

  12. Obesity-related colon cancer: dietary factors and their mechanisms of anticancer action.

    PubMed

    Zeng, Huawei; Lazarova, Darina L

    2012-02-01

    Overweight/obesity is an epidemic in the US as well as in other developed countries, affecting two-thirds of Americans and an estimated 2.3 billion people worldwide. Obesity increases the risk for Type 2 diabetes, cardiovascular disease and cancer. For example, epidemiological studies have established a strong association between obesity and colon cancer. It is generally accepted that metabolic changes associated with overweight/obesity, particularly abdominal obesity and changes in adipocyte function, contribute to the increased risk of colon cancer. Understanding the mechanisms underlying this association is important for the development of preventive strategies for colon cancer. Part of these preventive strategies may be based on dietary factors, such as vitamins, minerals (e.g. selenium), fibre, phytochemicals and phenolic compounds. These anticancer nutrients may counteract the molecular changes associated with obesity. The present article reviews the evidence that inflammation and insulin resistance induced by obesity are the molecular mediators of the association between obesity and colon cancer. We also evaluate the evidence for the ability of dietary factors to target the obesity-induced changes and, thus, protect against colon cancer.

  13. Integrating Multiple Analytical Datasets to Compare Metabolite Profiles of Mouse Colonic-Cecal Contents and Feces.

    PubMed

    Zeng, Huawei; Grapov, Dmitry; Jackson, Matthew I; Fahrmann, Johannes; Fiehn, Oliver; Combs, Gerald F

    2015-09-11

    The pattern of metabolites produced by the gut microbiome comprises a phenotype indicative of the means by which that microbiome affects the gut. We characterized that phenotype in mice by conducting metabolomic analyses of the colonic-cecal contents, comparing that to the metabolite patterns of feces in order to determine the suitability of fecal specimens as proxies for assessing the metabolic impact of the gut microbiome. We detected a total of 270 low molecular weight metabolites in colonic-cecal contents and feces by gas chromatograph, time-of-flight mass spectrometry (GC-TOF) and ultra-high performance liquid chromatography, quadrapole time-of-flight mass spectrometry (UPLC-Q-TOF). Of that number, 251 (93%) were present in both types of specimen, representing almost all known biochemical pathways related to the amino acid, carbohydrate, energy, lipid, membrane transport, nucleotide, genetic information processing, and cancer-related metabolism. A total of 115 metabolites differed significantly in relative abundance between both colonic-cecal contents and feces. These data comprise the first characterization of relationships among metabolites present in the colonic-cecal contents and feces in a healthy mouse model, and shows that feces can be a useful proxy for assessing the pattern of metabolites to which the colonic mucosum is exposed.

  14. Upregulation of activin A gene by butyrate in human colon cancer cell lines.

    PubMed

    Sonoyama, Kei; Pholnukulkit, Pimara; Toyoda, Masahiko; Rutatip, Suriya; Kasai, Takanori

    2003-06-01

    Activin A has been reported to play a role in the progression of colorectal cancer. Because dietary fiber protects against colorectal cancer, we hypothesized that butyrate, a fermentation product of dietary fiber, may affect the expression of activin A in colon cancer cells. Semiquantitative RT-PCR demonstrated that the activin A gene was upregulated by sodium butyrate in the human colon cancer cell lines HT-29 and Caco-2 in a concentration- and time-dependent manner. However, the activin A gene did not respond to sodium butyrate in the human normal colonic cell line FHC, rat normal intestinal epithelial cell (IEC) line IEC-6, and the explant of rat colon. Flow cytometry and agarose gel electrophoresis of genomic DNA revealed that cell cycle arrest and apoptosis were induced by sodium butyrate but not exogenous activin A in HT-29 cells, indicating that activin A could not act as an autocrine factor in colon cancer cells. By assuming that activin A promotes colorectal cancer spread as a paracrine factor, our findings suggest that butyrate could act as a tumor promoter in some circumstances.

  15. Colon capsule endoscopy: What we know and what we would like to know.

    PubMed

    Spada, Cristiano; Barbaro, Federico; Andrisani, Gianluca; Minelli Grazioli, Leonardo; Hassan, Cesare; Costamagna, Isabella; Campanale, Mariachiara; Costamagna, Guido

    2014-12-01

    Colonoscopy is usually perceived as an invasive and potentially painful procedure, being also affected by a small, but definite, risk of major complications (cardiopulmonary complications, perforation, hemorrhage) and even mortality. To improve both acceptability and safety, PillCam Colon Capsule Endoscopy (CCE) (Given Imaging Ltd, Yoqneam, Israel) has been developed. CCE represents a non-invasive technique that is able to explore the colon without sedation and air insufflation. The Second Generation of Colon Capsule Endoscopy (PillCam Colon 2) (CCE-2) was proven to be an accurate tool to detect colonic neoplastic lesions when used in average risk individuals. To date, the evidence supports the use of CCE-2 in case of colonoscopy failure, in patients unwilling to perform colonoscopy and when colonoscopy is contraindicated. Other potential applications, such as colorectal cancer screening or diagnostic surveillance of inflammatory bowel disease need to be clarified. In this paper, the current "state of the art", potential application of CCE and future needs are evaluated.

  16. Stercoral perforation of the colon during pregnancy.

    PubMed

    Matsushita, Tomoko; Yumoto, Yasuo; Fukushima, Kotaro; Hojo, Satoshi; Ohishi, Yoshihiro; Inoue, Shigetaka; Wake, Norio

    2011-11-01

    A 39-year-old Japanese woman was referred to our hospital for severe abdominal pain at 22 weeks and 2 days of gestation. Abdominal computed tomography (CT) suggested perforation of the gastrointestinal tract and emergency surgery was conducted. There was a fibrous adhesion between an enlarged uterus and the sigmoid colon. There was a 5.0-cm perforation near the adhesion in the posterior wall of the sigmoid colon. We performed a partial resection of the sigmoid colon and Hartmann's procedure with copious intraperitoneal lavage. Five hours following the laparotomy, uterine contractions could not be controlled and the patient delivered vaginally. The neonate died almost immediately after delivery. We conclude that although stercoral bowel perforation is rare, poor prognosis after perforation emphasizes the need to carry out a CT scan for patients who present with undiagnosed severe abdominal pain and compatible medical history, even if the patient is pregnant.

  17. The Actinobacterial Colonization of Etruscan Paintings

    PubMed Central

    Diaz-Herraiz, Marta; Jurado, Valme; Cuezva, Soledad; Laiz, Leonila; Pallecchi, Pasquino; Tiano, Piero; Sanchez-Moral, Sergio; Saiz-Jimenez, Cesareo

    2013-01-01

    The paintings from Tomba della Scimmia, in Tuscany, are representative of the heavy bacterial colonization experienced in most Etruscan necropolises. The tomb remained open until the late 70′s when it was closed because of severe deterioration of the walls, ceiling and paintings after decades of visits. The deterioration is the result of environmental changes and impacts suffered since its discovery in 1846. We show scanning electron microscopy and molecular studies that reveal the extent and nature of the biodeterioration. Actinobacteria, mainly Nocardia and Pseudonocardia colonize and grow on the tomb walls and this process is linked to the availability of organic matter, phyllosilicates (e.g. clay minerals) and iron oxides. Nocardia is found metabolically active in the paintings. The data confirm the specialization of the genera Nocardia and Pseudonocardia in the colonization of subterranean niches. PMID:23486535

  18. Adhesive bacterial colonization of exposed traumatized tendon.

    PubMed

    Webb, L X; Hobgood, C D; Meredith, J W; Gristina, A G

    1987-05-01

    Recent studies of compromised or damaged tissues, as well as biomaterials, have shown that they provide a particularly fertile substratum for bacterial colonization. Colonization in these environments is mediated by a process of microbial adhesion to surfaces of the substrata. In this report, we present electron microscopic studies of a portion of damaged and infected tendon. These studies demonstrate colonies of bacteria surrounded by a ruthenium red-staining exopolysaccharide biofilm and adhesion to the surface of the tendon by means of an exopolysaccharide polymer. We suggest that this adhesive form of bacterial colonization may partially explain the resistance of exposed tendon to effective debridement by simple mechanical measures and to coverage with granulation tissue, partial-thickness skin grafts, and vascularized tissue grafts.

  19. Pneumocystis jirovecii colonization in chronic pulmonary disease

    PubMed Central

    Gutiérrez, S.; Respaldiza, N.; Campano, E.; Martínez-Risquez, M.T.; Calderón, E.J.; De La Horra, C.

    2011-01-01

    Pneumocystis jirovecii causes pneumonia in immunosuppressed individuals. However, it has been reported the detection of low levels of Pneumocystis DNA in patients without signs and symptoms of pneumonia, which likely represents colonization. Several studies performed in animals models and in humans have demonstrated that Pneumocystis induces a local and a systemic response in the host. Since P. jirovecii colonization has been found in patients with chronic pulmonary diseases it has been suggested that P. jirovecii may play a role in the physiopathology and progression of those diseases. In this report we revise P. jirovecii colonization in different chronic pulmonary diseases such us, chronic obstructive pulmonary disease, interstitial lung diseases, cystic fibrosis and lung cancer. PMID:21678787

  20. The actinobacterial colonization of Etruscan paintings.

    PubMed

    Diaz-Herraiz, Marta; Jurado, Valme; Cuezva, Soledad; Laiz, Leonila; Pallecchi, Pasquino; Tiano, Piero; Sanchez-Moral, Sergio; Saiz-Jimenez, Cesareo

    2013-01-01

    The paintings from Tomba della Scimmia, in Tuscany, are representative of the heavy bacterial colonization experienced in most Etruscan necropolises. The tomb remained open until the late 70's when it was closed because of severe deterioration of the walls, ceiling and paintings after decades of visits. The deterioration is the result of environmental changes and impacts suffered since its discovery in 1846. We show scanning electron microscopy and molecular studies that reveal the extent and nature of the biodeterioration. Actinobacteria, mainly Nocardia and Pseudonocardia colonize and grow on the tomb walls and this process is linked to the availability of organic matter, phyllosilicates (e.g. clay minerals) and iron oxides. Nocardia is found metabolically active in the paintings. The data confirm the specialization of the genera Nocardia and Pseudonocardia in the colonization of subterranean niches.

  1. Prehistoric human colonization of India.

    PubMed

    Misra, V N

    2001-11-01

    Human colonization in India encompasses a span of at least half-a-million years and is divided into two broad periods, namely the prehistoric (before the emergence of writing) and the historic (after writing). The prehistoric period is divided into stone, bronze and iron ages. The stone age is further divided into palaeolithic, mesolithic and neolithic periods. As the name suggests, the technology in these periods was primarily based on stone. Economically, the palaeolithic and mesolithic periods represented a nomadic, hunting-gathering way of life, while the neolithic period represented a settled, food-producing way of life. Subsequently copper was introduced as a new material and this period was designated as the chalcolithic period. The invention of agriculture, which took place about 8000 years ago, brought about dramatic changes in the economy, technology and demography of human societies. Human habitat in the hunting-gathering stage was essentially on hilly, rocky and forested regions, which had ample wild plant and animal food resources. The introduction of agriculture saw it shifting to the alluvial plains which had fertile soil and perennial availability of water. Hills and forests, which had so far been areas of attraction, now turned into areas of isolation. Agriculture led to the emergence of villages and towns and brought with it the division of society into occupational groups. The first urbanization took place during the bronze age in the arid and semi-arid region of northwest India in the valleys of the Indus and the Saraswati rivers, the latter represented by the now dry Ghaggar-Hakra bed. This urbanization is known as the Indus or Harappan civilization which flourished during 3500-1500 B.C. The rest of India during this period was inhabited by neolithic and chalcolithic farmers and mesolithic hunter-gatherers. With the introduction of iron technology about 3000 years ago, the focus of development shifted eastward into the Indo-Gangetic divide and

  2. Prehistoric human colonization of India.

    PubMed

    Misra, V N

    2001-11-01

    Human colonization in India encompasses a span of at least half-a-million years and is divided into two broad periods, namely the prehistoric (before the emergence of writing) and the historic (after writing). The prehistoric period is divided into stone, bronze and iron ages. The stone age is further divided into palaeolithic, mesolithic and neolithic periods. As the name suggests, the technology in these periods was primarily based on stone. Economically, the palaeolithic and mesolithic periods represented a nomadic, hunting-gathering way of life, while the neolithic period represented a settled, food-producing way of life. Subsequently copper was introduced as a new material and this period was designated as the chalcolithic period. The invention of agriculture, which took place about 8000 years ago, brought about dramatic changes in the economy, technology and demography of human societies. Human habitat in the hunting-gathering stage was essentially on hilly, rocky and forested regions, which had ample wild plant and animal food resources. The introduction of agriculture saw it shifting to the alluvial plains which had fertile soil and perennial availability of water. Hills and forests, which had so far been areas of attraction, now turned into areas of isolation. Agriculture led to the emergence of villages and towns and brought with it the division of society into occupational groups. The first urbanization took place during the bronze age in the arid and semi-arid region of northwest India in the valleys of the Indus and the Saraswati rivers, the latter represented by the now dry Ghaggar-Hakra bed. This urbanization is known as the Indus or Harappan civilization which flourished during 3500-1500 B.C. The rest of India during this period was inhabited by neolithic and chalcolithic farmers and mesolithic hunter-gatherers. With the introduction of iron technology about 3000 years ago, the focus of development shifted eastward into the Indo-Gangetic divide and

  3. Piwil2 modulates the proliferation and metastasis of colon cancer via regulation of matrix metallopeptidase 9 transcriptional activity.

    PubMed

    Li, Dawei; Sun, Xing; Yan, Dongwang; Huang, Jianfeng; Luo, Qiongzhen; Tang, Huamei; Peng, Zhihai

    2012-10-01

    Piwi-like protein 2 (Piwil2) has recently emerged as a putative oncogene which is amplified in several human malignancies. However, the role of Piwil2 in colon cancer remains poorly understood. The aim of this study was to investigate the clinical and pathological significance of Piwil2, and the possible role in the proliferation and metastasis of colon cancer. Primary colon cancer paired with adjacent normal colon tissue and lymph node metastasis (LNM) lesions in 66 patients' tissue microarrays (TMA) were used to determine the expression of Piwil2. Knocked down Piwil2 expression in SW620 and SW480 colon cancer cell lines was performed to evaluate the role of Piwil2 in cell proliferation, invasion, metastasis in vitro and tumorigenicity in vivo. The possible roles of Piwil2 in the regulation of a 2 kb matrix metallopeptidase 9 (MMP9) promoter fragment and on the regulation of apoptotic pathways were evaluated by using a luciferase reporter construct and Western blots, respectively. Significantly higher expression levels of Piwil2 were observed in primary colon cancer tissue and in LNM in comparison with normal colon mucosa. Piwil2 expression significantly correlated with more aggressive clinical and pathological parameters with poorer five-year metastasis-free survival and overall survival. Piwil2 silencing significantly reduced cancer cell proliferation, colony formation ability and increased apoptosis in vitro and inhibited tumor growth in vivo. Piwil2 knockdown also attenuated migration and invasion of colon cancer cells via modulation of MMP9 transcriptional activities. Our results indicate that Piwil2 moderates the proliferation and metastasis potential of colon cancer.

  4. Metastatic colonization by circulating tumour cells.

    PubMed

    Massagué, Joan; Obenauf, Anna C

    2016-01-21

    Metastasis is the main cause of death in people with cancer. To colonize distant organs, circulating tumour cells must overcome many obstacles through mechanisms that we are only now starting to understand. These include infiltrating distant tissue, evading immune defences, adapting to supportive niches, surviving as latent tumour-initiating seeds and eventually breaking out to replace the host tissue. They make metastasis a highly inefficient process. However, once metastases have been established, current treatments frequently fail to provide durable responses. An improved understanding of the mechanistic determinants of such colonization is needed to better prevent and treat metastatic cancer.

  5. How to improve colon cancer screening rates.

    PubMed

    Alberti, Luiz Ronaldo; Garcia, Diego Paim Carvalho; Coelho, Debora Lucciola; De Lima, David Correa Alves; Petroianu, Andy

    2015-12-15

    Colorectal carcinoma is a common cause of death throughout the world and may be prevented by routine control, which can detect precancerous neoplasms and early cancers before they undergo malignant transformation or metastasis. Three strategies may improve colon cancer screening rates: convince the population about the importance of undergoing a screening test; achieve higher efficacy in standard screening tests and make them more available to the community and develop new more sensitive and efficacious screening methods and make them available as routine tests. In this light, the present study seeks to review these three means through which to increase colon cancer screening rates. PMID:26688708

  6. How to improve colon cancer screening rates

    PubMed Central

    Alberti, Luiz Ronaldo; Garcia, Diego Paim Carvalho; Coelho, Debora Lucciola; De Lima, David Correa Alves; Petroianu, Andy

    2015-01-01

    Colorectal carcinoma is a common cause of death throughout the world and may be prevented by routine control, which can detect precancerous neoplasms and early cancers before they undergo malignant transformation or metastasis. Three strategies may improve colon cancer screening rates: convince the population about the importance of undergoing a screening test; achieve higher efficacy in standard screening tests and make them more available to the community and develop new more sensitive and efficacious screening methods and make them available as routine tests. In this light, the present study seeks to review these three means through which to increase colon cancer screening rates. PMID:26688708

  7. Colonic biogeography in health and ulcerative colitis.

    PubMed

    Lavelle, Aonghus; Lennon, Grainne; Winter, Desmond C; O'Connell, P Ronan

    2016-09-01

    The relevance of biogeography to the distal gut microbiota has been investigated in both health and inflammatory bowel disease (IBD), however multiple factors, including sample type and methodology, microbiota characterization and interpersonal variability make the construction of a core model of colonic biogeography challenging. In addition, how phylogenetic classification relates to immunogenicity and whether consistent alterations in the microbiota are associated with ulcerative colitis (UC) remain open questions. This addendum seeks to review the human colonic microbiota in health and UC as currently understood, in the broader context of the human microbiome. PMID:27662587

  8. Experimental ulcerative disease of the colon.

    PubMed

    Watt, J; Marcus, R

    1975-01-01

    The oral administration to guinea-pigs of an aqueous solution of carrageenan derived from the red seaweed, Eucheuma spinosum, provides a useful, readily available experimental model for the study of ulcerative disease of the colon. Two types of ulcerative disease can be produced within a 4-6 week period, viz., ulceration localised mainly to the caecum by using 1% undegraded carrageenan in the drinking fluid, and extensive ulceration involving caecum, colon, and rectum by using 5% degraded carrageenan. Ulceration is probably due to the local action of carrageenan in the bowel. PMID:1202321

  9. Affective Learning.

    ERIC Educational Resources Information Center

    Brown, Charles T.

    This paper addresses itself to the question, "What does feeling have to do with knowing?" Two movements in affective education are discussed which have come into focus in recent years and which attempt to define the relationship between knowing and feeling. The first, a conscious application of the role of arousal in learning, emphasizes arousal…

  10. Bioimage analysis of Shigella infection reveals targeting of colonic crypts.

    PubMed

    Arena, Ellen T; Campbell-Valois, Francois-Xavier; Tinevez, Jean-Yves; Nigro, Giulia; Sachse, Martin; Moya-Nilges, Maryse; Nothelfer, Katharina; Marteyn, Benoit; Shorte, Spencer L; Sansonetti, Philippe J

    2015-06-23

    Few studies within the pathogenic field have used advanced imaging and analytical tools to quantitatively measure pathogenicity in vivo. In this work, we present a novel approach for the investigation of host-pathogen processes based on medium-throughput 3D fluorescence imaging. The guinea pig model for Shigella flexneri invasion of the colonic mucosa was used to monitor the infectious process over time with GFP-expressing S. flexneri. A precise quantitative imaging protocol was devised to follow individual S. flexneri in a large tissue volume. An extensive dataset of confocal images was obtained and processed to extract specific quantitative information regarding the progression of S. flexneri infection in an unbiased and exhaustive manner. Specific parameters included the analysis of S. flexneri positions relative to the epithelial surface, S. flexneri density within the tissue, and volume of tissue destruction. In particular, at early time points, there was a clear association of S. flexneri with crypts, key morphological features of the colonic mucosa. Numerical simulations based on random bacterial entry confirmed the bias of experimentally measured S. flexneri for early crypt targeting. The application of a correlative light and electron microscopy technique adapted for thick tissue samples further confirmed the location of S. flexneri within colonocytes at the mouth of crypts. This quantitative imaging approach is a novel means to examine host-pathogen systems in a tailored and robust manner, inclusive of the infectious agent. PMID:26056271

  11. Bioimage analysis of Shigella infection reveals targeting of colonic crypts.

    PubMed

    Arena, Ellen T; Campbell-Valois, Francois-Xavier; Tinevez, Jean-Yves; Nigro, Giulia; Sachse, Martin; Moya-Nilges, Maryse; Nothelfer, Katharina; Marteyn, Benoit; Shorte, Spencer L; Sansonetti, Philippe J

    2015-06-23

    Few studies within the pathogenic field have used advanced imaging and analytical tools to quantitatively measure pathogenicity in vivo. In this work, we present a novel approach for the investigation of host-pathogen processes based on medium-throughput 3D fluorescence imaging. The guinea pig model for Shigella flexneri invasion of the colonic mucosa was used to monitor the infectious process over time with GFP-expressing S. flexneri. A precise quantitative imaging protocol was devised to follow individual S. flexneri in a large tissue volume. An extensive dataset of confocal images was obtained and processed to extract specific quantitative information regarding the progression of S. flexneri infection in an unbiased and exhaustive manner. Specific parameters included the analysis of S. flexneri positions relative to the epithelial surface, S. flexneri density within the tissue, and volume of tissue destruction. In particular, at early time points, there was a clear association of S. flexneri with crypts, key morphological features of the colonic mucosa. Numerical simulations based on random bacterial entry confirmed the bias of experimentally measured S. flexneri for early crypt targeting. The application of a correlative light and electron microscopy technique adapted for thick tissue samples further confirmed the location of S. flexneri within colonocytes at the mouth of crypts. This quantitative imaging approach is a novel means to examine host-pathogen systems in a tailored and robust manner, inclusive of the infectious agent.

  12. An integrated analysis of the effects of past land use on forest herb colonization at the landscape scale

    USGS Publications Warehouse

    Verheyen, K.; Guntenspergen, G.R.; Biesbrouck, B.; Hermy, M.

    2003-01-01

    1 A framework that summarizes the direct and indirect effects of past land use on forest herb recolonization is proposed, and used to analyse the colonization patterns of forest under storey herbaceous species in a 360-ha mixed forest, grassland and arable landscape in the Dijle river valley (central Belgium). 2 Fine-scale distribution maps were constructed for 14 species. The species were mapped in 15946 forest plots and outside forests (along parcel margins) in 5188 plots. Forest stands varied in age between 1 and more than 224 years. Detailed land-use history data were combined with the species distribution maps to identify species-specific colonization sources and to calculate colonization distances. 3 The six most frequent species were selected for more detailed statistical analysis. 4 Logistic regression models indicated that species frcquency in forest parcels was a function of secondary forest age, distance from the nearest colonization source and their interaction. Similar age and distance effects were found within hedgerows. 5 In 199 forest stands, data about soils, canopy structure and the cover of competitive species were collected. The relative importance of habitat quality and spatio-temporal isolation tor the colonization of the forest herb species was quantified using structural equation modelling (SEM), within the framework proposed for the effects of past land use. 6 The results of the SEM indicate that, except for the better colonizing species, the measured habitat quality variables are of minor importance in explaining colonization patterns, compared with the combination of secondary forest age and distance from colonization sources. 7 Our results suggest the existence of a two-stage colonization process in which diaspore availability determines the initial pattern, which is affected by environmental sorting at later stages.

  13. An integrated analysis of the effects of past land use on forest herb colonization at the landscape scale

    USGS Publications Warehouse

    Verheyen, K.; Guntenspergen, G.R.; Beisbrouck, B.; Hermy, M.

    2003-01-01

    1. A framework that summarizes the direct and indirect effects of past land use on forest herb recolonization is proposed, and used to analyse the colonization patterns of forest understorey herbaceous species in a 360-ha mixed forest, grassland and arable landscape in the Dijle river valley (central Belgium). 2. Fine-scale distribution maps were constructed for 14 species. The species were mapped in 15 946 forest plots and outside forests (along parcel margins) in 5188 plots. Forest stands varied in age between 1 and more than 224 years. Detailed land-use history data were combined with the species distribution maps to identify species-specific colonization sources and to calculate colonization distances. 3. The six most frequent species were selected for more detailed statistical analysis. 4. Logistic regression models indicated that species frequency in forest parcels was a function of secondary forest age, distance from the nearest colonization source and their interaction. Similar age and distance effects were found within hedgerows. 5. In 199 forest stands, data about soils, canopy structure and the cover of competitive species were collected. The relative importance of habitat quality and spatio-temporal isolation for the colonization of the forest herb species was quantified using structural equation modelling (SEM), within the framework proposed for the effects of past land use. 6. The results of the SEM indicate that, except for the better colonizing species, the measured habitat quality variables are of minor importance in explaining colonization patterns, compared with the combination of secondary forest age and distance from colonization sources. 7. Our results suggest the existence of a two-stage colonization process in which diaspore availability determines the initial pattern, which is affected by environmental sorting at later stages.

  14. The use of sesame oil and other vegetable oils in the inhibition of human colon cancer growth in vitro.

    PubMed

    Salerno, J W; Smith, D E

    1991-01-01

    Sesame contains large quantities of the essential polyunsaturated fatty acid (PUFA), linoleic acid, in the form triglycerides. The antineoplastic properties of many PUFAs such as linoleic acid and their metabolites are known. We tested the hypothesis that natural vegetable oils, such as sesame oil and its component linoleic acid, when added to human colon adenocarcinoma cells growing in tissue culture would inhibit their growth and that normal colon cells would not be similarly affected. Three human colon cancer cell lines and one normal human colon cell line were exposed to the following: (1) pure linoleic acid; (2) lipase-digested sesame oil; (3) undigested sesame oil; (4) five additional common vegetable oils; (5) mineral oil. Linoleic acid inhibited the in vitro growth of all three malignant human colon adenocarcinoma cell lines. The normal colon cell line showed dramatically less inhibition of growth. Lipase-digested sesame oil (LDSO) and undigested sesame oil (UDSO) produced greater inhibition of growth of all three malignant colon cell lines than of the normal colon cells. Five other common vegetable oils containing various amounts of PUFAs such as corn, soybean, safflower, olive and coconut oils, all in their lipase-digested form, were found to dramatically inhibit the growth of the HT-29 malignant human colon cell line. Undigested olive and safflower oils also inhibited the HT-29 cells although not as markedly as the lipase-digested oils. Mineral oil did not inhibit the growth of HT-29 cells. Both lauric and palmitic acid, which are saturated fatty acids found in abundance in coconut oil inhibits the HT-29 cells more strongly than linoleic acid, while oleic acid did not inhibit. We conclude that many vegetable oils including sesame contain in vitro antineoplastic properties and that this finding warrants further investigation both in vitro and in vivo to assess their possible chemotherapeutic potential.

  15. DNA adduct formation and oxidative stress in colon and liver of Big Blue rats after dietary exposure to diesel particles.

    PubMed

    Dybdahl, Marianne; Risom, Lotte; Møller, Peter; Autrup, Herman; Wallin, Håkan; Vogel, Ulla; Bornholdt, Jette; Daneshvar, Bahram; Dragsted, Lars Ove; Weimann, Allan; Poulsen, Henrik Enghusen; Loft, Steffen

    2003-11-01

    Exposure to diesel exhaust particles (DEP) via the gastrointestinal route may impose risk of cancer in the colon and liver. We investigated the effects of DEP given in the diet to Big Blue rats by quantifying a panel of markers of DNA damage and repair, mutation, oxidative damage to proteins and lipids, and antioxidative defence mechanisms in colon mucosa cells, liver tissue and the blood compartment. Seven groups of rats were fed a diet with 0, 0.2, 0.8, 2, 8, 20 or 80 mg DEP/kg feed for 21 days. DEP induced a significant increase in DNA strand breaks in colon and liver. There was no effect on oxidative DNA damage (8-oxodG) in colon or liver DNA or in the urine. However, the mRNA expression of OGG1, encoding an enzyme involved in repair of 8-oxodG, was increased by DEP in both liver and colon. DNA adduct levels measured by 32P-post-labelling were elevated in colon and liver, and the expression of ERCC1 gene was affected in liver, but not in colon. In addition to these effects, DEP exposure induced apoptosis in liver. There was no significant change in mutation frequency in colon or liver. The levels of oxidative protein modifications (oxidized arginine and proline residues) were increased in liver accompanied by enhanced vitamin C levels. In plasma, we found no significant effects on oxidative damage to proteins and lipids, antioxidant enzymes or vitamin C levels. Our data indicate that gastrointestinal exposure to DEP induces DNA adducts and oxidative stress resulting in DNA strand breaks, enhanced repair capacity of oxidative base damage, apoptosis and protein oxidation in colon mucosa cells and liver.

  16. DNA adduct formation and oxidative stress in colon and liver of Big Blue rats after dietary exposure to diesel particles.

    PubMed

    Dybdahl, Marianne; Risom, Lotte; Møller, Peter; Autrup, Herman; Wallin, Håkan; Vogel, Ulla; Bornholdt, Jette; Daneshvar, Bahram; Dragsted, Lars Ove; Weimann, Allan; Poulsen, Henrik Enghusen; Loft, Steffen

    2003-11-01

    Exposure to diesel exhaust particles (DEP) via the gastrointestinal route may impose risk of cancer in the colon and liver. We investigated the effects of DEP given in the diet to Big Blue rats by quantifying a panel of markers of DNA damage and repair, mutation, oxidative damage to proteins and lipids, and antioxidative defence mechanisms in colon mucosa cells, liver tissue and the blood compartment. Seven groups of rats were fed a diet with 0, 0.2, 0.8, 2, 8, 20 or 80 mg DEP/kg feed for 21 days. DEP induced a significant increase in DNA strand breaks in colon and liver. There was no effect on oxidative DNA damage (8-oxodG) in colon or liver DNA or in the urine. However, the mRNA expression of OGG1, encoding an enzyme involved in repair of 8-oxodG, was increased by DEP in both liver and colon. DNA adduct levels measured by 32P-post-labelling were elevated in colon and liver, and the expression of ERCC1 gene was affected in liver, but not in colon. In addition to these effects, DEP exposure induced apoptosis in liver. There was no significant change in mutation frequency in colon or liver. The levels of oxidative protein modifications (oxidized arginine and proline residues) were increased in liver accompanied by enhanced vitamin C levels. In plasma, we found no significant effects on oxidative damage to proteins and lipids, antioxidant enzymes or vitamin C levels. Our data indicate that gastrointestinal exposure to DEP induces DNA adducts and oxidative stress resulting in DNA strand breaks, enhanced repair capacity of oxidative base damage, apoptosis and protein oxidation in colon mucosa cells and liver. PMID:12919963

  17. Campylobacter jejuni Colonization Is Associated with a Dysbiosis in the Cecal Microbiota of Mice in the Absence of Prominent Inflammation

    PubMed Central

    Lone, Abdul G.; Selinger, L. Brent; Uwiera, Richard R. E.; Xu, Yong; Inglis, G. Douglas

    2013-01-01

    Background Campylobacter jejuni causes enterocolitis in humans, but does not incite disease in asymptomatic carrier animals. To survive in the intestine, C. jejuni must successfully compete with the microbiota and overcome the host immune defense. Campylobacter jejuni colonization success varies considerably amongst individual mice, and we examined the degree to which the intestinal microbiota was affected in mice (i.e. a model carrier animal) colonized by C. jejuni at high relative to low densities. Methods Mice were inoculated with C. jejuni or buffer, and pathogen shedding and intestinal colonization were measured. Histopathologic scoring and quantification of mRNA expression for α-defensins, toll-like receptors, and cytokine genes were conducted. Mucosa-associated bacterial communities were characterized by two approaches: multiplexed barcoded pyrosequencing and terminal restriction fragment length polymorphism analysis. Results Two C. jejuni treatments were established based on the degree of cecal and colonic colonization; C. jejuni Group A animals were colonized at high cell densities, and C. jejuni Group B animals were colonized at lower cell densities. Histological examination of cecal and colonic tissues indicated that C. jejuni did not incite visible pathologic changes. Although there was no significant difference among treatments in expression of mRNA for α-defensins, toll-like receptors, or cytokine genes, a trend for increased expression of toll-like receptors and cytokine genes was observed for C. jejuni Group A. The results of the two methods to characterize bacterial communities indicated that the composition of the cecal microbiota of C. jejuni Group A mice differed significantly from C. jejuni Group B and Control mice. This difference was due to a reduction in load, diversity and richness of bacteria associated with the cecal mucosa of C. jejuni Group A mice. Conclusions High density colonization by C. jejuni is associated with a dysbiosis in

  18. An integrated analysis of the effects of past land use on forest herb colonization at the landscape scale

    USGS Publications Warehouse

    Verheyen, K.; Guntenspergen, Glenn R.; Biesbrouck, B.; Hermy, M.

    2003-01-01

    A framework that summarizes the direct and indirect effects of past land use on forest herb recolonization is proposed, and used to analyse the colonization patterns of forest understorey herbaceous species in a 360-ha mixed forest, grassland and arable landscape in the Dijle river valley (central Belgium).Fine-scale distribution maps were constructed for 14 species. The species were mapped in 15 946 forest plots and outside forests (along parcel margins) in 5188 plots. Forest stands varied in age between 1 and more than 224 years. Detailed land-use history data were combined with the species distribution maps to identify species-specific colonization sources and to calculate colonization distances.The six most frequent species were selected for more detailed statistical analysis.Logistic regression models indicated that species frequency in forest parcels was a function of secondary forest age, distance from the nearest colonization source and their interaction. Similar age and distance effects were found within hedgerows.In 199 forest stands, data about soils, canopy structure and the cover of competitive species were collected. The relative importance of habitat quality and spatio-temporal isolation for the colonization of the forest herb species was quantified using structural equation modelling (SEM), within the framework proposed for the effects of past land use.The results of the SEM indicate that, except for the better colonizing species, the measured habitat quality variables are of minor importance in explaining colonization p