Epithelioid hemangioendotheliomas of the liver and lung in children and adolescents.

PubMed

Hettmer, Simone; Andrieux, Geoffroy; Hochrein, Jochen; Kurz, Philipp; Rössler, Jochen; Lassmann, Silke; Werner, Martin; von Bubnoff, Nikolas; Peters, Christoph; Koscielniak, Ewa; Sparber-Sauer, Monika; Niemeyer, Charlotte; Mentzel, Thomas; Busch, Hauke; Boerries, Melanie

2017-12-01

Epithelioid hemangioendothelioma (EHE) is a rare, vascular sarcoma. Visceral forms arise in the liver/ lungs. We review the clinical and molecular phenotype of pediatric visceral EHE based on the case of a 9-year-old male child with EHE of the liver/lungs. His tumor expressed the EHE-specific fusion oncogene WWTR1-CAMTA1. Molecular characterization revealed a low somatic mutation rate and activated interferon signaling, angiogenesis regulation, and blood vessel remodeling. After polychemotherapy and resection of lung tumors, residual disease remained stable on oral lenalidomide. Literature review identified another 24 children with EHE of the liver/lungs. Most presented with multifocal, systemic disease. Only those who underwent complete resection achieved complete remission. Four children experienced rapid progression and died. In six children, disease remained stable for years without therapy. Two patients died from progressive EHE 21 and 24 years after first diagnosis. Natural evolution of pediatric visceral EHE is variable, and long-term prognosis remains unclear. © 2017 Wiley Periodicals, Inc.

The nucleotide-free state of heterotrimeric G proteins α-subunit adopts a highly stable conformation.

PubMed

Andhirka, Sai Krishna; Vignesh, Ravichandran; Aradhyam, Gopala Krishna

2017-08-01

Deciphering the mechanism of activation of heterotrimeric G proteins by their cognate receptors continues to be an intriguing area of research. The recently solved crystal structure of the ternary complex captured the receptor-bound α-subunit in an open conformation, without bound nucleotide has improved our understanding of the activation process. Despite these advancements, the mechanism by which the receptor causes GDP release from the α-subunit remains elusive. To elucidate the mechanism of activation, we studied guanine nucleotide-induced structural stability of the α-subunit (in response to thermal/chaotrope-mediated stress). Inherent stabilities of the inactive (GDP-bound) and active (GTP-bound) forms contribute antagonistically to the difference in conformational stability whereas the GDP-bound protein is able to switch to a stable intermediate state, GTP-bound protein loses this ability. Partial perturbation of the protein fold reveals the underlying influence of the bound nucleotide providing an insight into the mechanism of activation. An extra stable, pretransition intermediate, 'empty pocket' state (conformationally active-state like) in the unfolding pathway of GDP-bound protein mimics a gating system - the activation process having to overcome this stable intermediate state. We demonstrate that a relatively more complex conformational fold of the GDP-bound protein is at the core of the gating system. We report capturing this threshold, 'metastable empty pocket' conformation (the gate) of α-subunit of G protein and hypothesize that the receptor activates the G protein by enabling it to achieve this structure through mild structural perturbation. © 2017 Federation of European Biochemical Societies.

Changes in Physical Activity in the School, Afterschool, and Evening Periods During the Transition From Elementary to Middle School.

PubMed

Lau, Erica Y; Dowda, Marsha; McIver, Kerry L; Pate, Russell R

2017-07-01

We examined longitudinal changes in children's physical activity during the school day, afterschool, and evening across fifth, sixth, and seventh grades. The analytical sample included children who had valid accelerometer data in fifth grade and at least one other time-point, and provided complete sociodemographic information (N = 768, 751, and 612 for the 3 time-periods studied). Accelerometer-derived total physical activity (TPA) and moderate-to-vigorous physical activity (MVPA) were expressed in minutes per hour for the school day (∼7:45 am to 3:30 pm), afterschool (∼2:25 to 6:00 pm), and evening (6:00 to 10:00 pm) periods. We used growth curve analyses to examine changes in TPA and MVPA. School day TPA and MVPA declined significantly; we observed a greater decrease from fifth to sixth grades than from sixth to seventh grades. Afterschool TPA declined significantly, but MVPA increased significantly among girls and remained stable for boys. Evening TPA decreased significantly and MVPA declined significantly in girls and remained stable among boys. To inform the development of effective intervention strategies, research should focus on examining factors associated with the decline in physical activity during the transition from elementary to middle school, particularly during the hours when children are in school. © 2017, American School Health Association.

Identifying Low pH Active and Lactate-Utilizing Taxa within Oral Microbiome Communities from Healthy Children Using Stable Isotope Probing Techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

McLean, Jeffrey S.; Fansler, Sarah J.; Majors, Paul D.

Many human microbial infectious diseases including dental caries are polymicrobial in nature and how these complex multi-species communities evolve from a healthy to a diseased state is not well understood. Although many health- or disease-associated oral microbes have been characterized in vitro, their physiology in vivo in the presence of the complex oral microbiome is difficult to determine with current approaches. In addition, about half of these oral species remain uncultivated to date and little is known except their 16S rRNA sequence. Lacking culture-based physiological analyses, the functional roles of uncultivated microorganisms will remain enigmatic despite their apparent disease correlation.more » To start addressing these knowledge gaps, we applied a novel combination of in vivo Magnetic Resonance Spectroscopy (MRS) with RNA and DNA based Stable Isotope Probing (SIP) to oral plaque communities from healthy children for temporal monitoring of carbohydrate utilization, organic acid production and identification of metabolically active and inactive bacterial species.« less

Imaging Features of Patients Undergoing Active Surveillance for Ductal Carcinoma in Situ.

PubMed

Grimm, Lars J; Ghate, Sujata V; Hwang, E Shelley; Soo, Mary Scott

2017-11-01

The aim of this study was to describe the imaging appearance of patients undergoing active surveillance for ductal carcinoma in situ (DCIS). We retrospectively identified 29 patients undergoing active surveillance for DCIS from 2009 to 2014. Twenty-two patients (group 1) refused surgery or were not surgical candidates. Seven patients (group 2) enrolled in a trial of letrozole and deferred surgical excision for 6-12 months. Pathology and imaging results at the initial biopsy and follow-up were recorded. In group 1, the median follow-up was 2.7 years (range: 0.6-13.9 years). Fifteen patients (68%) remained stable. Seven patients (32%) underwent additional biopsies with invasive ductal carcinoma diagnosed in two patients after 3.9 and 3.6 years who developed increasing calcifications and new masses. In group 2, one patient (14%) was upstaged to microinvasive ductal carcinoma at surgery. Among the patients in both groups with calcifications (n = 26), there was no progression to invasive disease among those with stable (50%, 13/26) or decreased (19%, 5/26) calcifications. Among a DCIS active surveillance cohort, invasive disease progression presented as increasing calcifications and a new mass following more than 3.5 years of stable imaging. In contrast, there was no progression to invasive disease among cases of DCIS with stable or decreasing calcifications. Close imaging is a key follow-up component in active surveillance. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Application of extracellular lipopeptide biosurfactant produced by endophytic Bacillus subtilis K1 isolated from aerial roots of banyan (Ficus benghalensis) in microbially enhanced oil recovery (MEOR).

PubMed

Pathak, Khyati V; Keharia, Hareshkumar

2014-02-01

Bacillus subtilis K1 isolated from aerial roots of banyan tree secreted mixture of surfactins, iturins and fengycins with high degree of heterogeneity. The extracellular extract consisting of mixture of these cyclic lipopeptides exhibited very good emulsification activity as well as excellent emulsion stability. The culture accumulated maximum surfactant up to 48 h of growth during batch fermentation in Luria broth. The emulsion of hexane, heptane and octane prepared using 48-h-old culture supernatant of B. subtilis K1 remained stable up to 2 days while emulsion of four stroke engine oil remained stable for more than a year. The critical micelle concentration of crude lipopeptide biosurfactant extracted by acid precipitation from 48-h-old fermentation broth of B. subtilis K1 was found to be 20.5 μg/mL. The biosurfactant activity was found to be stable at 100 °C for 2 h, over a pH range of 6-12 h and over an NaCl concentration up to 10 % (w/v). The application of biosurfactant on laboratory scale sand pack column saturated with four stroke engine oil resulted in ~43 % enhanced oil recovery, suggesting its suitability in microbially enhanced oil recovery.

Emergence of a Stable Cortical Map for Neuroprosthetic Control

PubMed Central

Ganguly, Karunesh; Carmena, Jose M.

2009-01-01

Cortical control of neuroprosthetic devices is known to require neuronal adaptations. It remains unclear whether a stable cortical representation for prosthetic function can be stored and recalled in a manner that mimics our natural recall of motor skills. Especially in light of the mixed evidence for a stationary neuron-behavior relationship in cortical motor areas, understanding this relationship during long-term neuroprosthetic control can elucidate principles of neural plasticity as well as improve prosthetic function. Here, we paired stable recordings from ensembles of primary motor cortex neurons in macaque monkeys with a constant decoder that transforms neural activity to prosthetic movements. Proficient control was closely linked to the emergence of a surprisingly stable pattern of ensemble activity, indicating that the motor cortex can consolidate a neural representation for prosthetic control in the presence of a constant decoder. The importance of such a cortical map was evident in that small perturbations to either the size of the neural ensemble or to the decoder could reversibly disrupt function. Moreover, once a cortical map became consolidated, a second map could be learned and stored. Thus, long-term use of a neuroprosthetic device is associated with the formation of a cortical map for prosthetic function that is stable across time, readily recalled, resistant to interference, and resembles a putative memory engram. PMID:19621062

Two-step membrane binding by the bacterial SRP receptor enable efficient and accurate Co-translational protein targeting.

PubMed

Hwang Fu, Yu-Hsien; Huang, William Y C; Shen, Kuang; Groves, Jay T; Miller, Thomas; Shan, Shu-Ou

2017-07-28

The signal recognition particle (SRP) delivers ~30% of the proteome to the eukaryotic endoplasmic reticulum, or the bacterial plasma membrane. The precise mechanism by which the bacterial SRP receptor, FtsY, interacts with and is regulated at the target membrane remain unclear. Here, quantitative analysis of FtsY-lipid interactions at single-molecule resolution revealed a two-step mechanism in which FtsY initially contacts membrane via a Dynamic mode, followed by an SRP-induced conformational transition to a Stable mode that activates FtsY for downstream steps. Importantly, mutational analyses revealed extensive auto-inhibitory mechanisms that prevent free FtsY from engaging membrane in the Stable mode; an engineered FtsY pre-organized into the Stable mode led to indiscriminate targeting in vitro and disrupted FtsY function in vivo. Our results show that the two-step lipid-binding mechanism uncouples the membrane association of FtsY from its conformational activation, thus optimizing the balance between the efficiency and fidelity of co-translational protein targeting.

Development of a New Generation of Stable, Tunable, and Catalytically Active Nanoparticles Produced by the Helium Nanodroplet Deposition Method

DOE PAGES

Wu, Qiyuan; Ridge, Claron J.; Zhao, Shen; ...

2016-07-13

Nanoparticles (NPs) are revolutionizing many areas of science and technology, often delivering unprecedented improvements to properties of the conventional materials. However, despite important advances in NPs synthesis and applications, numerous challenges still remain. Development of alternative synthetic method capable of producing very uniform, extremely clean and very stable NPs is urgently needed. If successful, such method can potentially transform several areas of nanoscience, including environmental and energy related catalysis. Here we present the first experimental demonstration of catalytically active NPs synthesis achieved by the helium nanodroplet isolation method. This alternative method of NPs fabrication and deposition produces narrowly distributed, clean,more » and remarkably stable NPs. The fabrication is achieved inside ultra-low temperature, superfluid helium nanodroplets, which can be subsequently deposited onto any substrate. Lastly, this technique is universal enough to be applied to nearly any element, while achieving high deposition rates for single element as well as composite core-shell NPs.« less

Relationship between consumption of MRSA-active antibiotics and burden of MRSA in acute care hospitals in Catalonia, Spain.

PubMed

Grau, Santiago; Fondevilla, Esther; Freixas, Núria; Mojal, Sergi; Sopena, Nieves; Bella, Feliu; Gudiol, Francesc

2015-04-01

To analyse the possible relationship between consumption of old and new MRSA-active antibiotics and burden of MRSA in acute care hospitals in Catalonia during the period 2007-12. Fifty-four hospitals participating in the VINCat Programme were included. Proportion of MRSA (resistant isolates of Staphylococcus aureus per 100 isolates of S. aureus tested), incidence of new cases of infection [new cases of MRSA per 1000 occupied bed-days (OBD)] and incidence of cases of bacteraemia (MRSA bacteraemia cases per 1000 OBD) were determined to estimate the annual MRSA burden. Antibiotic consumption was calculated in DDD/100 OBD. Cost was expressed in euros/100 OBD. MRSA rates remained stable over the study period, with the proportion of MRSA ranging from 20% to 22.82% in 2007 and 2012, respectively (P=0.864). Consumption of old MRSA-active antibiotics (vancomycin and teicoplanin) did not change significantly, with values from 1.51 to 2.07 DDD/100 OBD (P=0.693). Consumption of new MRSA-active antibiotics (linezolid and daptomycin) increased significantly, with values rising from 0.24 to 1.49 DDD/100 OBD (P<0.001). Cost increased by almost 200%. A widespread and steady increase in consumption of new MRSA-active antibiotics was observed among acute care hospitals in Catalonia, in spite of a stable MRSA burden. At the same time, consumption of old drugs remained stable. Such trends resulted in a significant increase in cost. Our findings suggest that factors other than the proportion of methicillin resistance among S. aureus may influence the use of old and new MRSA-active antibiotics in the clinical setting. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

PSYCHOLOGICAL FACTORS IN 155 PATIENTS WITH FUNCTIONAL UTERINE BLEEDING.

PubMed

DUTTON, W A

1965-02-20

One hundred and fifty-five women with functional uterine bleeding were studied to evaluate the importance of concomitant psychological disorders. Psychological illnesses were diagnosed in 128 patients (82.6%), most of which arose from problems directly related to sexual or reproductive functions. The remaining 27 patients (17.4%) were different in that they were psychologically stable and all but two were at puberty or approaching the menopause.Histological studies of endometrial samples from 135 of these patients indicated little evidence of abnormal sex hormone activity; 77 (57%) showed normal secretory phase endometrium and 32 (23.7%), proliferative phase endometrium. The remaining 26 (19.2%) showed evidence of some endocrine dysfunction, 15 such specimens being obtained from psychologically stable patients.It is probable that psychological disturbances are the principal cause of functional uterine bleeding during the prime reproductive years. The psychological component of the illness is the most important and determines the ultimate prognosis.

Development of a Freeze-Dried, Heat-Stable Influenza Subunit Vaccine Formulation

PubMed Central

Flood, Alexander; Chen, Dexiang

2016-01-01

An influenza pandemic remains a major public health concern. A key strategy to prevent a pandemic is to stockpile and pre-position stable influenza vaccine to allow rapid deployment in response to an outbreak. However, most influenza vaccines today are formulated as liquids that are stable only within a temperature range of 2°C to 8°C and require use of a cold chain, making vaccine transportation, distribution, and storage complicated and expensive, particularly for developing countries. To support the National Strategy for Pandemic Influenza preparedness in the United States and internationally, we developed two lead dry formulations of stable H1N1 influenza subunit vaccines using freeze-drying technology. The stable formulations contain an excipient combination of a disaccharide, such as sucrose or trehalose, and glycine, in addition to a surfactant and phosphate buffer. The freeze-dried vaccines were shown to be safe and remained immunogenic in an in vivo study in mice. Moreover, the lead formulations demonstrated no significant loss of activity after 40 months at storage temperatures of 25°C and 37°C. This stability can be particularly attractive as it could eliminate the need to use a cold chain for vaccine deployment and facilitate integration of vaccine distribution with general drug distribution where appropriate. These freeze-dried thermostable influenza subunit vaccines could also reduce the frequency of vaccine stockpile turnover, offering a cost-effective option for pandemic preparedness. PMID:27851765

Development of a Freeze-Dried, Heat-Stable Influenza Subunit Vaccine Formulation.

PubMed

Flood, Alexander; Estrada, Marcus; McAdams, David; Ji, Yuhua; Chen, Dexiang

2016-01-01

An influenza pandemic remains a major public health concern. A key strategy to prevent a pandemic is to stockpile and pre-position stable influenza vaccine to allow rapid deployment in response to an outbreak. However, most influenza vaccines today are formulated as liquids that are stable only within a temperature range of 2°C to 8°C and require use of a cold chain, making vaccine transportation, distribution, and storage complicated and expensive, particularly for developing countries. To support the National Strategy for Pandemic Influenza preparedness in the United States and internationally, we developed two lead dry formulations of stable H1N1 influenza subunit vaccines using freeze-drying technology. The stable formulations contain an excipient combination of a disaccharide, such as sucrose or trehalose, and glycine, in addition to a surfactant and phosphate buffer. The freeze-dried vaccines were shown to be safe and remained immunogenic in an in vivo study in mice. Moreover, the lead formulations demonstrated no significant loss of activity after 40 months at storage temperatures of 25°C and 37°C. This stability can be particularly attractive as it could eliminate the need to use a cold chain for vaccine deployment and facilitate integration of vaccine distribution with general drug distribution where appropriate. These freeze-dried thermostable influenza subunit vaccines could also reduce the frequency of vaccine stockpile turnover, offering a cost-effective option for pandemic preparedness.

Conducting polymer nanostructures for photocatalysis under visible light

NASA Astrophysics Data System (ADS)

Ghosh, Srabanti; Kouamé, Natalie A.; Ramos, Laurence; Remita, Samy; Dazzi, Alexandre; Deniset-Besseau, Ariane; Beaunier, Patricia; Goubard, Fabrice; Aubert, Pierre-Henri; Remita, Hynd

2015-05-01

Visible-light-responsive photocatalysts can directly harvest energy from solar light, offering a desirable way to solve energy and environment issues. Here, we show that one-dimensional poly(diphenylbutadiyne) nanostructures synthesized by photopolymerization using a soft templating approach have high photocatalytic activity under visible light without the assistance of sacrificial reagents or precious metal co-catalysts. These polymer nanostructures are very stable even after repeated cycling. Transmission electron microscopy and nanoscale infrared characterizations reveal that the morphology and structure of the polymer nanostructures remain unchanged after many photocatalytic cycles. These stable and cheap polymer nanofibres are easy to process and can be reused without appreciable loss of activity. Our findings may help the development of semiconducting-based polymers for applications in self-cleaning surfaces, hydrogen generation and photovoltaics.

Physical activity decreased by a quarter in the 11- to 12-year-old Swedish boys between 2000 and 2013 but was stable in girls: a smartphone effect?

PubMed

Raustorp, Anders; Pagels, Peter; Fröberg, Andreas; Boldemann, Cecilia

2015-08-01

This study explored physical activity, body mass index (BMI) and overweight and obesity from 2000 to 2013 using a convenience sample of second- and fifth-grade Swedish schoolchildren aged 8-9 years and 11-12 years, respectively. We examined cross-sectional cohorts of 126 second-grade children in 2000, 84 in 2006 and 44 in 2013 and 105 fifth-grade children in 2000 and 38 in 2013. No fifth graders were available in 2006. Physical activity data were collected based on pedometer readings over four consecutive weekdays, and height and weight were measured. Identical instruments and procedures were used in all three years. There was an increase in physical activity in second-grade girls from 2000 to 2006 (p < 0.01), which then stabilised between 2006 and 2013, but second-grade boys and fifth-grade girls were stable throughout the study period. Fifth-grade boys decreased significantly (24%) from 16 670 to 12 704 steps per day (p < 0.01) from 2000 to 2013. Mean BMI scores remained stable over time. Time trends in physical activity differed between boys and girls. Second-grade boys and fifth-grade girls were stable throughout, whereas second-grade girls increased from 2000 to 2006 before stabilising. Fifth-grade boys showed a significant 24% reduction from 2000 to 2013. Changes in recess and leisure time habits, such as smartphone use, may have influenced the result. ©2015 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Time-Resolved Records of Magnetic Activity on the Pallasite Parent Body and Psyche

NASA Astrophysics Data System (ADS)

Bryson, J. F. J.; Nichols, C. I. O.; Herrero-Albillos, J.; Kronast, F.; Kasama, T.; Alimadadi, H.; van der Laan, G.; Nimmo, F.; Harrison, R. J.

2014-12-01

Although many small bodies apparently generated dynamo fields in the early solar system, the nature and temporal evolution of these fields has remained enigmatic. Time-resolved records of the Earth's planetary field have been essential in understanding the dynamic history of our planet, and equivalent information from asteroids could provide a unique insight into the development of the solar system. Here we present time-resolved records of magnetic activity on the main-group pallasite parent body and (16) Psyche, obtained using newly-developed nanomagnetic imaging techniques. For the pallasite parent body, the inferred field direction remained relatively constant and the intensity was initially stable at ~100 μT before it decreased in two discrete steps down to 0 μT. We interpret this behaviour as due to vigorous dynamo activity driven by compositional convection in the core, ultimately transitioning from a dipolar to multipolar field as the inner core grew from the bottom-up. For Psyche (measured from IVA iron meteorites), the inferred field direction reversed, while the intensity remained stable at >50 μT. Psyche cooled rapidly as an unmantled core, although the resulting thermal convection alone cannot explain these observations. Instead, this behaviour required top-down core solidification, and is attributed either to compositional convection (if the core also solidified from the bottom-up) or convection generated directly by top-down solidification (e.g. Fe-snow). The mechanism governing convection in small body cores is an open question (due partly to uncertainties in the direction of core solidification), and these observations suggest that unconventional (i.e. not thermal) mechanisms acted in the early solar system. These mechanisms are very efficient at generating convection, implying a long-lasting and widespread epoch of dynamo activity among small bodies in the early solar system.

Acetabular Cup Revision.

PubMed

Kim, Young-Ho

2017-09-01

The use of acetabular cup revision arthroplasty is on the rise as demands for total hip arthroplasty, improved life expectancies, and the need for individual activity increase. For an acetabular cup revision to be successful, the cup should gain stable fixation within the remaining supportive bone of the acetabulum. Since the patient's remaining supportive acetabular bone stock plays an important role in the success of revision, accurate classification of the degree of acetabular bone defect is necessary. The Paprosky classification system is most commonly used when determining the location and degree of acetabular bone loss. Common treatment options include: acetabular liner exchange, high hip center, oblong cup, trabecular metal cup with augment, bipolar cup, bulk structural graft, cemented cup, uncemented cup including jumbo cup, acetabular reinforcement device (cage), trabecular metal cup cage. The optimal treatment option is dependent upon the degree of the discontinuity, the amount of available bone stock and the likelihood of achieving stable fixation upon supportive host bone. To achieve successful acetabular cup revision, accurate evaluation of bone defect preoperatively and intraoperatively, proper choice of method of acetabular revision according to the evaluation of acetabular bone deficiency, proper technique to get primary stability of implant such as precise grafting technique, and stable fixation of implant are mandatory.

Effect of physical activity level on biomarkers of inflammation and insulin resistance over 5 years in outpatients with coronary heart disease (from the Heart and Soul Study).

PubMed

Jarvie, Jennifer L; Whooley, Mary A; Regan, Mathilda C; Sin, Nancy L; Cohen, Beth E

2014-10-15

Higher levels of physical activity are associated with lower rates of coronary heart disease (CHD). Previous studies have suggested that this is due partly to lower levels of inflammation and insulin resistance. The aim of this study was to determine whether physical activity level was associated with inflammation or insulin resistance during a 5-year period in outpatients with known CHD. A total of 656 participants from the Heart and Soul Study, a prospective cohort study of outpatients with documented CHD, were evaluated. Self-reported physical activity frequency was assessed at baseline and after 5 years of follow-up. Participants were classified as low versus high activity at each visit, yielding 4 physical activity groups: stable low activity, decreasing activity (high at baseline to low at year 5), increasing activity (low at baseline to high at year 5), and stable high activity. Year 5 markers of inflammation (C-reactive protein [CRP], interleukin-6, and fibrinogen) and insulin resistance (insulin, glucose, and glycated hemoglobin) were compared across the 4 activity groups. After 5 years of follow-up, higher activity was associated with lower mean levels of all biomarkers. In the fully adjusted regression models, CRP, interleukin-6, and glucose remained independently associated with physical activity frequency (log CRP, p for trend across activity groups = 0.03; log interleukin-6, p for trend = 0.01; log glucose, p for trend = 0.003). Subjects with stable high activity typically had the lowest levels of biomarkers. In conclusion, in this novel population of outpatients with known CHD followed for 5 years, higher physical activity frequency was independently associated with lower levels of CRP, interleukin-6, and glucose. Copyright © 2014 Elsevier Inc. All rights reserved.

Janus droplets: liquid marbles coated with dielectric/semiconductor particles.

PubMed

Bormashenko, Edward; Bormashenko, Yelena; Pogreb, Roman; Gendelman, Oleg

2011-01-04

The manufacturing of water droplets wrapped with two different powders, carbon black (semiconductor) and polytetrafluoroethylene (dielectric), is presented. Droplets composed of two hemispheres (Janus droplets) characterized by various physical and chemical properties are reported first. Watermelon-like striped liquid marbles are reported. Janus droplets remained stable on solid and liquid supports and could be activated with an electric field.

Production of Cellulolytic and Hemicellulolytic Enzymes From Aureobasidium pulluans on Solid State Fermentation

NASA Astrophysics Data System (ADS)

Leite, Rodrigo Simões Ribeiro; Bocchini, Daniela Alonso; da Silva Martins, Eduardo; Silva, Dênis; Gomes, Eleni; da Silva, Roberto

This article investigates a strain of the yeast Aureobasidium pullulans for cellulase and hemicellulase production in solid state fermentation. Among the substrates analyzed, the wheat bran culture presented the highest enzymatic production (1.05 U/mL endoglucanase, 1.3 U/mL β-glucosidase, and 5.0 U/mL xylanase). Avicelase activity was not detected. The optimum pH and temperature for xylanase, endoglucanase and β-glucosidase were 5.0 and 50, 4.5 and 60, 4.0 and 75°C, respectively. These enzymes remained stable between a wide range of pH. The β-glucosidase was the most thermostable enzyme remaining 100% active when incubated at 75°C for 1 h.

Fish skin gelatin hydrolysates produced by visceral peptidase and bovine trypsin: Bioactivity and stability.

PubMed

Ketnawa, Sunantha; Benjakul, Soottawat; Martínez-Alvarez, Oscar; Rawdkuen, Saroat

2017-01-15

The peptidase from the viscera of farmed giant catfish was used for producing gelatin hydrolysates (HG) and compared with those produced from commercial bovine trypsin (HB). The degree of hydrolysis (DH) observed suggests that proteolytic cleavage rapidly occurred within the first 120min of incubation, and there was higher DH in HG than in HB. HG demonstrated the highest ACE-inhibitory activity, DPPH, ABTS radical scavenging activity, and FRAP. HB showed the highest FRAP activity. The DPPH radical scavenging activity of HG was quite stable over the pH range of 1-11, but it increased slightly when the heating duration time reached 240min at 100°C. The ACE-inhibitory activity of HG showed the highest stability at a pH of 7, and it remained very stable at 100°C for over 15-240min. The visceral peptidase from farmed giant catfish could be an alternative protease for generating protein hydrolysates with desirable bioactivities. The resulting hydrolysates showed good stability, making them potential functional ingredients for food formulations. Copyright © 2016 Elsevier Ltd. All rights reserved.

Preparation of novel stable antibacterial nanoparticles using hydroxyethylcellulose and application in paper.

PubMed

Wei, Dafu; Chen, Yan; Zhang, Youwei

2016-01-20

Taking advantage of the self-assembly between the components, novel stable antibacterial nanoparticles were efficiently fabricated via a facile one-step co-polymerization of acrylic acid (AA) and N,N'-methylenebisacrylamide (MBA) on a mixed aqueous solution of poly(hexamethylene guanidine hydrochloride) (PHMG) and hydroxyethylcellulose (HEC). The z-average hydrodynamic diameters of the nanoparticles ranged from 220 nm to 450 nm. The inner layer of the nanoparticles is composed of water-insoluble interpolymer complexes of PHMG and PAA networks, while the outer layer is composed of PHMG and HEC. The nanoparticles are stabilized by electrostatic interactions, hydrogen bonding interactions, and the chemical bonds. The nanoparticle solution remained stable in a wide pH range of 2.0-12.0 and at salt concentrations below 0.25 mol/L. The nanoparticles were incorporated into handsheets using a dipping treatment. The resulted handsheets exhibited excellent antimicrobial activities even after multiple water washing treatments. The nanoparticles are promising in fabricating paper, water-based coatings and textiles with permanent antibacterial activity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Increasing physical activity, but persisting social gaps among middle-aged people: trends in Northern Sweden from 1990 to 2007.

PubMed

Ng, Nawi; Söderman, Kerstin; Norberg, Margareta; Öhman, Ann

2011-01-01

Physical activity is identified as one important protective factor for chronic diseases. Physical activity surveillance is important in assessing healthy population behaviour over time. Many countries lack population trends on physical activity. To present trends in physical activity levels in Västerbotten County, Sweden and to evaluate physical activity among women and men with various educational levels. Population-based cross-sectional and panel data from the Västerbotten Intervention Programme (VIP) during 1990-2007 were used. All individuals in Västerbotten County who turned 40, 50, or 60 years old were invited to their local primary health care for a health screening. Physical activity during commuting, recreational activities, physical exercise, and socio-demographic data were collected using a self-administered questionnaire. Respondents were categorised as sedentary, moderate physically active, or physically active. The prevalences of physically active behaviours increased from 16 to 24.2% among men and from 12.6 to 30.4% among women. Increases are observed in all educational groups, but gaps between educational groups widened recently. The level of sedentary behaviour was stable over the time period studied. The 10-year follow-up data show that the prevalences of physically active behaviours increased from 15.8 to 21.4% among men and 12.7 to 23.3% among women. However, 10.2% of men and 3.8% of women remained sedentary. Despite the promising evidence of increasing physical activity levels among the population in Västerbotten County, challenges remain for how to reduce the stable levels of sedentary behaviours in some subgroups. Persisting social gaps in physical activity levels should be addressed further. An exploration of people's views on engaging in physical activity and barriers to doing so will allow better formulation of targeted interventions within this population. Global Health Action 2011. © 2011 N. Ng et al.

Substitutions of cysteine residues of Escherichia coli heat-stable enterotoxin by oligonucleotide-directed mutagenesis.

PubMed Central

Okamoto, K; Okamoto, K; Yukitake, J; Kawamoto, Y; Miyama, A

1987-01-01

The Escherichia coli 18-amino-acid, heat-stable enterotoxin STp has six cysteine residues linked intramolecularly by three disulfide bonds. These disulfide bonds are important for toxic activity, but the precise role of each bond is not clear. We substituted cysteine residues of STp in vivo by oligonucleotide-directed site-specific mutagenesis to dissociate each disulfide bond and examined the biological activities of the resulting mutants. The Cys-6----Ala and Cys-17----Ala mutations caused a complete loss of toxic activity. The Cys-5----Ala, Cys-10----Ser, and Gly-16, Cys-17----Cys-16, Gly-17 mutations caused a large decrease in toxic activity. These results mean that all three disulfide bonds formed at fixed positions are required for full expression of the biological activity of STp. However, a weak but significant toxicity still remained after three mutations, Cys-5----Ala, Cys-10----Ser, and Gly-16, Cys-17----Cys-16, Gly-17. This indicates that STp has some flexibilities in its conformation to exert toxic activity and that the role of each disulfide bond exerting toxic activity is not quite the same. Images PMID:3305364

Structure and Activity Changes of Phytohemagglutinin from Red Kidney Bean (Phaseolus vulgaris) Affected by Ultrahigh-Pressure Treatments.

PubMed

Lu, Yunjun; Liu, Cencen; Zhao, Mouming; Cui, Chun; Ren, Jiaoyan

2015-11-04

Phytohemagglutin (PHA), purified from red kidney beans (Phaseolus vulgaris) by Affi-Gel blue affinity chromatography, was subjected to ultrahigh-pressure (UHP) treatment (150, 250, 350, and 450 MPa). The purified PHA lost its hemagglutination activity after 450 MPa treatment and showed less pressure tolerance than crude PHA. However, the saccharide specificity and α-glucosidase inhibition activity of the purified PHA did not change much after UHP treatment. Electrophoresis staining by periodic acid-Schiff (PAS) manifested that the glycone structure of purified PHA remained stable even after 450 MPa pressure treatment. However, electrophoresis staining by Coomassie Blue as well as circular dichroism (CD) and differential scanning calorimetry (DSC) assay proved that the protein unit structure of purified PHA unfolded when treated at 0-250 MPa but reaggregates at 250-450 MPa. Therefore, the hemagglutination activity tends to be affected by the protein unit structure, while the stability of the glycone structure contributed to the remaining α-glucosidase inhibition activity.

Phytosynthesis of Silver Nanoparticles Using Myrtus communis L. Leaf Extract and Investigation of Bactericidal Activity

NASA Astrophysics Data System (ADS)

Ajdari, M. R.; Tondro, G. H.; Sattarahmady, N.; Parsa, A.; Heli, H.

2017-12-01

Silver nanoparticles have been synthesized using only Myrtus communis L. leaf extract by a facile procedure without other reagents. The extract played the roles of both reducing and capping agent. The nanoparticles were characterized using field-emission scanning microscopy, and remained stable for at least 3 weeks. Antibacterial activity of the nanoparticles was evaluated toward Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, and Enterococcus faecalis based on inhibition zone disk diffusion assays. The minimum inhibitory and bactericidal concentrations of the nanoparticles were obtained. Mechanisms for the antibacterial activity were proposed.

Experimental Civilian Personnel Office Project (EXPO): Final Report for Nonappropriated Fund Sites

DTIC Science & Technology

1991-07-01

existing data bases; budgetary data; and other documents provided by the test sites. The results indicate that EXPO initiatives had a positive impact on...EXPO has had a positive impact on NAF operations and profitability of revenue-generating activities has remained stable. Important findings include...appropriate education and training resources are available. v viii VllI CONTENTS INTRO DU CTIO N

Ab initio study of Fe(+)-benzyne

NASA Technical Reports Server (NTRS)

Bauschlicher, Charles W., Jr.

1993-01-01

The interaction of Fe(+) with benzyne is studied using the self-consistent-field (SCF), complete active space SCF, and modified-coupled-pair functional levels of theory. The most stable structure is planar, where the Fe(+) has inserted into the in-plane pi bond, although the C-C bond distance suggests that some in-plane pi bonding remains. This system is compared with Sc(+) bonding to benzyne and other ligands.

Surface engineering of hierarchical platinum-cobalt nanowires for efficient electrocatalysis

DOE PAGES

Bu, Lingzheng; Guo, Shaojun; Zhang, Xu; ...

2016-06-29

Despite intense research in past decades, the lack of high-performance catalysts for fuel cell reactions remains a challenge in realizing fuel cell technologies for transportation applications. Here we report a facile strategy for synthesizing hierarchical platinum-cobalt nanowires with high-index, platinum-rich facets and ordered intermetallic structure. These structural features enable unprecedented performance for the oxygen reduction and alcohol oxidation reactions. The specific/mass activities of the platinum-cobalt nanowires for oxygen reduction reaction are 39.6/33.7 times higher than commercial Pt/C catalyst, respectively. Density functional theory simulations reveal that the active threefold hollow sites on the platinum-rich high-index facets provide an additional factor inmore » enhancing oxygen reduction reaction activities. The nanowires are stable in the electrochemical conditions and also thermally stable. Furthermore, this work may represent a key step towards scalable production of high performance platinum-based nanowires for applications in catalysis and energy conversion.« less

Computational Chemistry-Based Identification of Ultra-Low Temperature Water-Gas-Shift Catalysts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Manos Mavrikakis

2008-08-31

The current work seeks to identify novel, catalytically-active, stable, poison-resistant LWGS catalysts that retain the superior activity typical of conventional Cu catalysts but can be operated at similar or lower temperatures. A database for the Binding Energies (BEs) of the LWGS relevant species, namely CO, O and OH on the most-stable, close-packed facets of a set of 17 catalytically relevant transition metals was established. This BE data and a database of previously established segregation energies was utilized to predict the stability of bimetallic NSAs that could be synthesized by combinations of the 17 parent transition metals. NSAs that were potentiallymore » stable both in vacuo and under the influence of strong-binding WGS intermediates were then selected for adsorption studies. A set of 40 NSAs were identified that satisfied all three screener criteria and the binding energies of CO, O and OH were calculated on a set of 66, 43 and 79 NSA candidates respectively. Several NSAs were found that bound intermediates weaker than the monometallic catalysts and were thus potentially poison-resistant. Finally, kinetic studies were performed and resulted in the discovery of a specific NSA-based bimetallic catalyst Cu/Pt that is potentially a promising LWGS catalyst. This stable Cu/Pt subsurface alloy is expected to provide facile H{sub 2}O activation and remain relatively resistant from the poisoning by CO, S and formate intermediates.« less

Use of birth control pills, condoms, and withdrawal among U.S. high school students.

PubMed

Everett, S A; Warren, C W; Santelli, J S; Kann, L; Collins, J L; Kolbe, L J

2000-08-01

To examine the use of contraception at last sexual intercourse among currently sexually active adolescents. We analyzed data from national school-based Youth Risk Behavior Surveys (YRBS) conducted in 1991, 1993, 1995, and 1997. The YRBS is a self-administered, anonymous survey which uses a national probability sample of U.S. students in public and private schools from grades 9 through 12. From 1991 to 1997, condom use significantly increased (from 46% to 57%), birth control pill use decreased (from 21% to 17%), and use of withdrawal significantly decreased (from 18% to 13%). In 1997, although more students were using condoms, 13% reported using withdrawal and 15% reported using no method to prevent pregnancy at last sexual intercourse. In 1997, condom use among females was significantly lower in the 9th grade than in the 12th grade (p <.001), whereas birth control pill use was higher (p <.001) and use of withdrawal remained stable. Among males, condom use and withdrawal use remained stable from 9th to 12th grade, whereas birth control pill use by their partner increased (p <.001). Inadequate contraceptive use among sexually active adolescents continues to be a major public health problem in the United States. For young people who will not remain sexually abstinent, families, health care providers, schools, and other influential societal institutions should promote the correct and continued use of condoms as essential protection against sexually transmitted diseases and human immunodeficiency virus infection.

Physical and antimicrobial properties of thyme oil emulsions stabilized by ovalbumin and gum arabic.

PubMed

Niu, Fuge; Pan, Weichun; Su, Yujie; Yang, Yanjun

2016-12-01

Natural biopolymer stabilized oil-in-water emulsions were formulated using ovalbumin (OVA), gum arabic (GA) solutions and their complexes. The influence of interfacial structure of emulsion (OVA-GA bilayer and OVA/GA complexes emulsions) on the physical properties and antimicrobial activity of thyme oil (TO) emulsion against Escherichia coli (E. coli) was evaluated. The results revealed that the two types of emulsions with different oil phase compositions remained stable during a long storage period. The oil phase composition had an appreciable influence on the mean particle diameter and retention of the TO emulsions. The stable emulsion showed a higher minimum inhibitory concentration (MIC), and the TO emulsions showed an improved long-term antimicrobial activity compared to the pure thyme oil, especially complexes emulsion at pH 4.0. These results provided useful information for developing protection and delivery systems for essential oil using biopolymer. Copyright © 2016 Elsevier Ltd. All rights reserved.

Expression, purification and characterization of soluble red rooster laforin as a fusion protein in Escherichia coli.

PubMed

Brewer, M Kathryn; Husodo, Satrio; Dukhande, Vikas V; Johnson, Mary Beth; Gentry, Matthew S

2014-04-02

The gene that encodes laforin, a dual-specificity phosphatase with a carbohydrate-binding module, is mutated in Lafora disease (LD). LD is an autosomal recessive, fatal progressive myoclonus epilepsy characterized by the intracellular buildup of insoluble, hyperphosphorylated glycogen-like particles, called Lafora bodies. Laforin dephosphorylates glycogen and other glucans in vitro, but the structural basis of its activity remains unknown. Recombinant human laforin when expressed in and purified from E. coli is largely insoluble and prone to aggregation and precipitation. Identification of a laforin ortholog that is more soluble and stable in vitro would circumvent this issue. In this study, we cloned multiple laforin orthologs, established a purification scheme for each, and tested their solubility and stability. Gallus gallus (Gg) laforin is more stable in vitro than human laforin, Gg-laforin is largely monomeric, and it possesses carbohydrate binding and phosphatase activity similar to human laforin. Gg-laforin is more soluble and stable than human laforin in vitro, and possesses similar activity as a glucan phosphatase. Therefore, it can be used to model human laforin in structure-function studies. We have established a protocol for purifying recombinant Gg-laforin in sufficient quantity for crystallographic and other biophysical analyses, in order to better understand the function of laforin and define the molecular mechanisms of Lafora disease.

Activation of intentional mechanisms through utilization of nonsymbolic movements in aphasia rehabilitation.

PubMed

Richards, Katherine; Singletary, Floris; Rothi, Leslie J Gonzalez; Koehler, Shirley; Crosson, Bruce

2002-01-01

Intentional mechanisms play an important role in complex self-initiated actions, such as language and gesturing. Deficits demonstrated in nonfluent aphasia may be a result of a disconnection between or damage to the initiation (intention) and production mechanisms in the left hemisphere. In chronic nonfluent aphasias, damaged language production mechanisms in the left hemisphere may switch to homologous regions in the right hemisphere while the initiation mechanisms remain active in the left hemisphere. A treatment was developed to prime right-hemisphere initiation mechanisms with movements of the nondominant hand, thereby bringing initiation into the right hemisphere where the language production mechanisms have been shifted. Three subjects with stable, chronic nonfluent aphasias were trained in daily sessions with a therapist to perform a complex nonsymbolic movement sequence with their nondominant hand to initiate naming trials of simple line drawings. Naming probes were administered during pre treatment baseline sessions and before each treatment session. All three subjects demonstrated a stable baseline and a significant increase over baseline performance in the percentage correct on naming probes during the treatment. Findings indicate that more extensive investigations of this newly developed treatment are justified and suggest that activation of right-hemisphere initiation mechanisms may enhance word production accuracy in stable, chronic nonfluent aphasias.

Neural Activity Associated with Visual Search for Line Drawings on AAC Displays: An Exploration of the Use of fMRI.

PubMed

Wilkinson, Krista M; Dennis, Nancy A; Webb, Christina E; Therrien, Mari; Stradtman, Megan; Farmer, Jacquelyn; Leach, Raevynn; Warrenfeltz, Megan; Zeuner, Courtney

2015-01-01

Visual aided augmentative and alternative communication (AAC) consists of books or technologies that contain visual symbols to supplement spoken language. A common observation concerning some forms of aided AAC is that message preparation can be frustratingly slow. We explored the uses of fMRI to examine the neural correlates of visual search for line drawings on AAC displays in 18 college students under two experimental conditions. Under one condition, the location of the icons remained stable and participants were able to learn the spatial layout of the display. Under the other condition, constant shuffling of the locations of the icons prevented participants from learning the layout, impeding rapid search. Brain activation was contrasted under these conditions. Rapid search in the stable display was associated with greater activation of cortical and subcortical regions associated with memory, motor learning, and dorsal visual pathways compared to the search in the unpredictable display. Rapid search for line drawings on stable AAC displays involves not just the conceptual knowledge of the symbol meaning but also the integration of motor, memory, and visual-spatial knowledge about the display layout. Further research must study individuals who use AAC, as well as the functional effect of interventions that promote knowledge about array layout.

relA-dependent RNA polymerase activity in Escherichia coli.

PubMed Central

Ryals, J; Bremer, H

1982-01-01

Parameters relating to RNA synthesis were measured after a temperature shift from 30 to 42 degrees C, in a relA+ and relA- isogenic pair of Escherichia coli strains containing a temperature-sensitive valyl tRNA synthetase. The following results were obtained: (i) the rRNA chain growth rate increased 2-fold in both strains; (ii) newly synthesized rRNA became unstable in both strains; (iii) the stable RNA gene activity (rRNA and tRNA, measured as stable RNA synthesis rate relative to the total instantaneous rate of RNA synthesis) decreased 1.7-fold in the relA+ strain and increased 1.9-fold in the relA mutant; and (iv) the RNA polymerase activity (measured by the percentage of total RNA polymerase enzyme active in transcription an any instant) decreased from 20 to 3.6% in the relA+ strain and remained unchanged (or increased at most to 22%) in the relA mutant. It is suggested that both rRNA gene activity and the RNA polymerase activity depend on the intracellular concentration of guanosine tetraphosphate, whereas the altered chain elongation rate and stability of rRNA are temperature or amino acid starvation effects, respectively, without involvement of relA function. PMID:6174501

Physical activity and inflammatory markers over 10 years: follow-up in men and women from the Whitehall II cohort study.

PubMed

Hamer, Mark; Sabia, Severine; Batty, G David; Shipley, Martin J; Tabák, Adam G; Singh-Manoux, Archana; Kivimaki, Mika

2012-08-21

Inflammatory processes are putative mechanisms underlying the cardioprotective effects of physical activity. An inverse association between physical activity and inflammation has been demonstrated, but no long-term prospective data are available. We therefore examined the association between physical activity and inflammatory markers over a 10-year follow-up period. Participants were 4289 men and women (mean age, 49.2 years) from the Whitehall II cohort study. Self-reported physical activity and inflammatory markers (serum high-sensitivity C-reactive protein and interleukin-6) were measured at baseline (1991) and follow-up (2002). Forty-nine percent of the participants adhered to standard physical activity recommendations for cardiovascular health (2.5 h/wk moderate to vigorous physical activity) across all assessments. Physically active participants at baseline had lower C-reactive protein and interleukin-6 levels, and this difference remained stable over time. Compared with participants who rarely adhered to physical activity guidelines over the 10-year follow-up, the high-adherence group displayed lower log(e) C-reactive protein (β=-0.07; 95% confidence interval, -0.12 to -0.02) and log(e) interleukin-6 (β=-0.07; 95% confidence interval, -0.10 to -0.03) at follow-up after adjustment for a range of covariates. Compared with participants who remained stable, those who reported an increase in physical activity of at least 2.5 h/wk displayed lower log(e) C-reactive protein (β coefficient=-0.05; 95% confidence interval, -0.10 to -0.001) and log(e) interleukin-6 (β coefficient=-0.06; 95% confidence interval, -0.09 to -0.03) at follow-up. Regular physical activity is associated with lower markers of inflammation over 10 years of follow-up and thus may be important in preventing the proinflammatory state seen with aging.

Extraction, purification and characterization of a protease from Micrococcus sp. VKMM 037.

PubMed

Manikandan, Muthu; Kannan, Vijayaraghavan; Pasić, Lejla

2011-10-01

The haloalkaliphilic bacterium Micrococcus sp. VKMM 037, isolated from an effluent of the caustic soda industry, was found to produce a protease. Maximal proteolytic activity was observed in cell culture grown at 40 degrees C using 2% (w/v) glycerol, 2% (w/v) beef extract and 2% (w/v) peptone as nutrients in medium also containing 0.85 M NaCl with a pH of 10.0. An efficient purification procedure combining ammonium sulphate precipitation and Q-Sepharose ion-exchange chromatography was developed. The purified 41 kDa protease was stable in a temperature range between 20 degrees C and 60 degrees C. The protease remained active over a wide range of pH values (4.0-12.0) and NaCl concentrations (0-3.42 M) with an optimum at pH 10.0 and 0.85 M NaCl, respectively. Furthermore, the enzyme remained stable or was only marginally inhibited in the presence of various organic solvents, surfactants and reducing agents. The purified protease of Micrococcus sp. VKMM 037 efficiently removed blood stains within 40 minutes of treatment. Given the biochemical characteristics determined, this novel protease could be exploited as an additive in the detergent industry and also for the synthesis of biomolecules and the degradation of protein.

Lactose digestion by yogurt beta-galactosidase: influence of pH and microbial cell integrity.

PubMed

Martini, M C; Bollweg, G L; Levitt, M D; Savaiano, D A

1987-02-01

Lactase-deficient subjects more effectively digest lactose in yogurt than lactose in other dairy products, apparently due to yogurt microbial beta-galactosidase (beta-gal) which is active in the GI tract. We evaluated the effects of buffering capacity of yogurt, gastric pH, and microbial cell disruption on beta-gal activity and lactose digestion. Three times more acid was required to acidify yogurt than to acidify milk. Yogurt beta-gal was stable at pH 4.0 but inactivated at lower pH. When yogurt was sonicated to disrupt microbial cell structure, only 20% activity remained after incubation at pH 4.0 for 60 min. In vivo gastric pH remained greater than 2.7 for 3 h after ingestion of yogurt. Acidified milk alone or with disrupted yogurt microorganisms caused twice as much lactose malabsorption as did acidified milk containing intact yogurt microorganisms. The results provide a possible explanation for the survival of beta-gal activity from yogurt in the GI tract.

Isolation and characterization of a cold-active, alkaline, detergent stable α-amylase from a novel bacterium Bacillus subtilis N8.

PubMed

Arabacı, Nihan; Arıkan, Burhan

2018-05-28

A cold-active alkaline amylase producer Bacillus subtilis N8 was isolated from soil samples. Amylase synthesis optimally occurred at 15°C and pH 10.0 on agar plates containing starch. The molecular weight of the enzyme was found to be 205 kDa by performing SDS-PAGE. While the enzyme exhibited the highest activity at 25°C and pH 8.0, it was highly stable in alkaline media (pH 8.0-12.0) and retained 96% of its original activity at low temperatures (10-40°C) for 24 hr. While the amylase activity increased in the presence of β-mercaptoethanol (103%); Ba 2+ , Ca 2+ , Na + , Zn 2+ , Mn 2+ , H 2 O 2 , and Triton X-100 slightly inhibited the activity. The enzyme showed resistance to some denaturants: such as SDS, EDTA, and urea (52, 65, and 42%, respectively). N8 α-amylase displayed the maximum remaining activity of 56% with 3% NaCl. The major final products of starch were glucose, maltose, and maltose-derived oligosaccharides. This novel cold-active α-amylase has the potential to be used in the industries of detergent and food, bioremediation process and production of prebiotics.

Aging accelerates memory extinction and impairs memory restoration in Drosophila.

PubMed

Chen, Nannan; Guo, Aike; Li, Yan

2015-05-15

Age-related memory impairment (AMI) is a phenomenon observed from invertebrates to human. Memory extinction is proposed to be an active inhibitory modification of memory, however, whether extinction is affected in aging animals remains to be elucidated. Employing a modified paradigm for studying memory extinction in fruit flies, we found that only the stable, but not the labile memory component was suppressed by extinction, thus effectively resulting in higher memory loss in aging flies. Strikingly, young flies were able to fully restore the stable memory component 3 h post extinction, while aging flies failed to do so. In conclusion, our findings reveal that both accelerated extinction and impaired restoration contribute to memory impairment in aging animals. Copyright © 2015 Elsevier Inc. All rights reserved.

Changes in aerobic performance, body composition, and physical activity in polar explorers during a year-long stay at the polar station in the Arctic

NASA Astrophysics Data System (ADS)

Maciejczyk, Marcin; Araźny, Andrzej; Opyrchał, Marta

2017-04-01

The aim of this study was to evaluate changes in physical activity, aerobic performance, and body composition in polar explorers during a 1-year stay at the polar station. The study group consisted of 10 people, including 8 men and 2 women. Aerobic performance (maximal oxygen uptake), physical activity, body mass, and composition were evaluated for the polar explores of the Polish Polar Station prior to departure, and then during their stay at the station for a period of 1 year. The measurements were performed every 3 months. Compared to the measurements taken before going to the polar station, aerobic performance significantly ( p = 0.02) increased in the first 3 months of residing at the polar station and then remained relatively stable for the following duration of the stay. In the first 3 months of the stay, we also observed the highest level of physical activity in participants. In the polar explorers, no significant ( p > 0.05) body fatness changes were noted. Nonetheless, lean body mass, body mass, and BMI significantly increased compared to the measurements taken before departure to the polar station. The greatest changes in aerobic performance, physical activity, and body composition were observed during the first 3 months after arrival to the Arctic and then, despite changing biometeorological conditions, they remained stable for the next months of the stay. We recommend the introduction of a physical preparation program before departing to the polar station to improve explorers' physical fitness, so that they can meet the physical challenges they are faced with immediately after arrival to the polar station.

The effect of unstable sandals on instability in gait in healthy female subjects.

PubMed

Price, Carina; Smith, Laura; Graham-Smith, Philip; Jones, Richard

2013-07-01

Unstable footwear generally lacks thorough peer-review published research to support concepts and marketing claims. The purpose of this study was to investigate the instability induced by four (FitFlop, Masai Barefoot Technology, Reebok Easy-Tone and Skechers Tone-Ups) commercially available unstable sandals and one stable control sandal (Earth) in walking in 15 females (mean±SD age was 29±6.7 years, mass 62.6±6.9kg and height 167.1±4.2cm). Three-dimensional motion with synchronised electromyography and kinetic data were collected. Walking speed and step length remained consistent between conditions, however double support time decreased in Masai Barefoot Technology. Centre of pressure data identified no consistent difference between the stable control and the unstable sandals, however Masai Barefoot Technology reduced the anterior-posterior range of centre of pressure. Muscle activity differed significantly at the ankle in the unstable footwear. FitFlop, Reebok and Skechers increased peroneal activity during pre-swing, whereas Masai Barefoot Technology increased medial gastrocnemius and decreased tibialis anterior activity in loading response and mid-stance. The larger rocker sole of the Masai Barefoot Technology altered gait and muscle activation with regard to braking and progression in the sagittal plane. Reebok, Skechers and FitFlop, with softer, less stable foreparts increased evertor action at toe-off, having their effect in the coronal plane. The study highlighted that any instability induced by the shoes is design-specific. Copyright © 2013 Elsevier B.V. All rights reserved.

Self-assembled air-stable magnesium hydride embedded in 3-D activated carbon for reversible hydrogen storage.

PubMed

Shinde, S S; Kim, Dong-Hyung; Yu, Jin-Young; Lee, Jung-Ho

2017-06-01

The rational design of stable, inexpensive catalysts with excellent hydrogen dynamics and sorption characteristics under realistic environments for reversible hydrogen storage remains a great challenge. Here, we present a simple and scalable strategy to fabricate a monodispersed, air-stable, magnesium hydride embedded in three-dimensional activated carbon with periodic synchronization of transition metals (MHCH). The high surface area, homogeneous distribution of MgH 2 nanoparticles, excellent thermal stability, high energy density, steric confinement by carbon, and robust architecture of the catalyst resulted in a noticeable enhancement of the hydrogen storage performance. The resulting MHCH-5 exhibited outstanding hydrogen storage performance, better than that of most reported Mg-based hydrides, with a high storage density of 6.63 wt% H 2 , a rapid kinetics loading in <5 min at 180 °C, superior reversibility, and excellent long-term cycling stability over ∼435 h. The significant reduction of the enthalpy and activation energy observed in the MHCH-5 demonstrated enhancement of the kinetics of de-/hydrogenation compared to that of commercial MgH 2 . The origin of the intrinsic hydrogen thermodynamics was elucidated via solid state 1 H NMR. This work presents a readily scaled-up strategy towards the design of realistic catalysts with superior functionality and stability for applications in reversible hydrogen storage, lithium ion batteries, and fuel cells.

210Po and 210Pb trophic transfer within the phytoplankton-zooplankton-anchovy/sardine food web: a case study from the Gulf of Lion (NW Mediterranean Sea).

PubMed

Strady, Emilie; Harmelin-Vivien, Mireille; Chiffoleau, Jean François; Veron, Alain; Tronczynski, Jacek; Radakovitch, Olivier

2015-05-01

The transfer of (210)Po and (210)Pb in the food web of small pelagic fishes (from phytoplankton and zooplankton to anchovy Engraulis encrasicolus and sardine Sardina pilchardus) is investigated in the Gulf of Lion (GoL). We present original data of (210)Po and (210)Pb activity concentrations, C and N stable isotope ratios, measured (i) from different size classes of phytoplankton and zooplankton during spring and winter in different environments of the GoL, and (ii) in two fish species. Significant spatial patterns based on (210)Po, (210)Pb activity concentrations and (210)Po/(210)Pb ratios in the different plankton size classes are evidenced by hierarchical clustering, both in spring and winter. This variability, also observed for C and N stable isotopes ratios, is connected to local specific pelagic habitats and hydrodynamics. The sampling strategy suggests that (210)Po bioaccumulation in the GoL remains at a constant level from the first (dominated by phytoplankton) to the second trophic level (zooplankton), while (210)Pb bioaccumulation shows an increase in winter. Based on stable N isotope ratios and (210)Po activity concentrations measured in anchovies and sardines, we evidence (210)Po bio-magnification along the trophic food web of these two planktivorous pelagic fishes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Operating principles of tristable circuits regulating cellular differentiation

NASA Astrophysics Data System (ADS)

Jia, Dongya; Jolly, Mohit Kumar; Harrison, William; Boareto, Marcelo; Ben-Jacob, Eshel; Levine, Herbert

2017-06-01

Many cell-fate decisions during embryonic development are governed by a motif comprised of two transcription factors (TFs) A and B that mutually inhibit each other and may self-activate. This motif, called as a self-activating toggle switch (SATS), can typically have three stable states (phenotypes)—two corresponding to differentiated cell fates, each of which has a much higher level of one TF than the other—≤ft(A,~B\\right)=≤ft(1,~0\\right) or ≤ft(0,~1\\right) —and the third state corresponding to an ‘undecided’ stem-like state with similar levels of both A and B—≤ft(A,~B\\right)=≤ft(1/2,1/2\\right) . Furthermore, two or more SATSes can be coupled together in various topologies in different contexts, thereby affecting the coordination between multiple cellular decisions. However, two questions remain largely unanswered: (a) what governs the co-existence and relative stability of these three stable states? (b) What orchestrates the decision-making of coupled SATSes? Here, we first demonstrate that the co-existence and relative stability of the three stable states in an individual SATS can be governed by the relative strength of self-activation, external signals activating and/or inhibiting A and B, and mutual degradation between A and B. Simultaneously, we investigate the effects of these factors on the decision-making of two coupled SATSes. Our results offer novel understanding into the operating principles of individual and coupled tristable self-activating toggle switches (SATSes) regulating cellular differentiation and can yield insights into synthesizing three-way genetic circuits and understanding of cellular reprogramming.

The effects of surface condition on abdominal muscle activity during single-legged hold exercise.

PubMed

Ha, Sung-min; Oh, Jae-seop; Jeon, In-cheol; Kwon, Oh-yun

2015-02-01

To treat low-back pain, various spinal stability exercises are commonly used to improve trunk muscle function and strength. Because human movement for normal daily activity occurs in multi-dimensions, the importance of exercise in multi-dimensions or on unstable surfaces has been emphasized. Recently, a motorized rotating platform (MRP) for facilitating multi-dimensions dynamic movement was introduced for clinical use. However, the abdominal muscle activity with this device has not been reported. The purpose of this study was to compare the abdominal muscle activity (rectus abdominis, external and internal oblique muscles) during an active single-leg-hold (SLH) exercise on a floor (stable surface), foam roll, and motorized rotating platform (MRP). Thirteen healthy male subjects participated in this study. Using electromyography, the abdominal muscle activity was measured while the subjects performed SLH exercises on floor (stable surface), foam roll, and MRP. There were significant differences in the abdominal muscle activities among conditions (P<.05), except for left EO (P>.05) (Fig. 2). After the Bonferroni correction, however, no significant differences among conditions remained, except for differences in both side IO muscle activity between the floor and foam roll conditions (padj<0.017). The findings suggest that performing the SLH exercises on a foam roll and MRP is more effective increased activities of both side of RA and IO, and Rt. EO compared to floor condition. However, there were no significant differences in abdominal muscles activity in the multiple comparison between conditions (mean difference were smaller than the standard deviation in the abdominal muscle activities) (padj>0.017), except for differences in both side IO muscle activity between the floor (stable surface) and foam roll (padj<0.017) (effect size: 0.79/0.62 (non-supporting/supporting leg) for foam-roll versus floor). Copyright © 2014 Elsevier Ltd. All rights reserved.

Characterization of tobermolite as a bed material for selective growth of methanotrophs in biofiltration.

PubMed

Kim, Tae Gwan; Jeong, So-Yeon; Cho, Kyung-Suk

2014-03-10

Tobermolite was characterized as a bed material for methanotrophic biofiltration. A lab-scale biofilter packed with tobermolite was operated for different operation times under identical conditions. The three different runs showed similar acclimation patterns of methane oxidation, with methane removal efficiency increasing rapidly for the first few days and peaking within three weeks, after which the efficiency remained stable. The mean methane removal capacities ranged from 766gm(-3)d(-1) to 974gm(-3)d(-1) after acclimation. Pyrosequencing indicated that the methanotrophic proportion (methanotroph/bacteria) increased to 71-94% within three weeks. Type I methanotrophs Methylocaldum and Methylosarcina were dominant during the initial growth period, then Methylocaldum alone dominated the methanotrophic community. A community comparison showed that total bacterial and methanotrophic communities were temporally stable after the initial growth period. Quantitative PCR showed that methanotrophic density increased during the first 3-4 weeks, then remained stable over 120 days. Tobermolite can provide a special habitat for the selective growth of methanotrophs, resulting in rapid acclimation. Tobermolite also allows the microbial community and methanotrophic density to remain stable, resulting in stable methane biofiltration. Copyright © 2014 Elsevier B.V. All rights reserved.

Design of active and stable Co-Mo-S x chalcogels as pH-universal catalyst for the hydrogen evolution reaction

DOE PAGES

Staszak-Jirkovský, Jakub; Malliakas, Christos D.; Lopes, Pietro P.; ...

2015-11-30

Three of the fundamental catalytic limitations that have plagued the electrochemical production of hydrogen for decades still remain: low efficiency, short lifetime of catalysts and a lack of low-cost materials. Here, we address these three challenges by establishing and exploring an intimate functional link between the reactivity and stability of crystalline (CoS 2 and MoS 2) and amorphous (CoS x and MoS x) hydrogen evolution catalysts. We propose that Co 2+ and Mo 4+ centers promote the initial discharge of water (alkaline solutions) or hydronium ions (acid solutions). We establish that although CoS x materials are more active than MoSmore » x they are also less stable, suggesting that the active sites are defects formed after dissolution of Co and Mo cations. Finally, by combining the higher activity of CoS x building blocks with the higher stability of MoS x units into a compact and robust CoMoS x structure, we are able to design a low-cost alternative to noble metal catalysts for efficient electrocatalytic production of hydrogen in both alkaline and acidic environments.« less

First Line Treatment Response in Patients with Transmitted HIV Drug Resistance and Well Defined Time Point of HIV Infection: Updated Results from the German HIV-1 Seroconverter Study

PubMed Central

zu Knyphausen, Fabia; Scheufele, Ramona; Kücherer, Claudia; Jansen, Klaus; Somogyi, Sybille; Dupke, Stephan; Jessen, Heiko; Schürmann, Dirk; Hamouda, Osamah; Meixenberger, Karolin; Bartmeyer, Barbara

2014-01-01

Background Transmission of drug-resistant HIV-1 (TDR) can impair the virologic response to antiretroviral combination therapy. Aim of the study was to assess the impact of TDR on treatment success of resistance test-guided first-line therapy in the German HIV-1 Seroconverter Cohort for patients infected with HIV between 1996 and 2010. An update of the prevalence of TDR and trend over time was performed. Methods Data of 1,667 HIV-infected individuals who seroconverted between 1996 and 2010 were analysed. The WHO drug resistance mutations list was used to identify resistance-associated HIV mutations in drug-naïve patients for epidemiological analysis. For treatment success analysis the Stanford algorithm was used to classify a subset of 323 drug-naïve genotyped patients who received a first-line cART into three resistance groups: patients without TDR, patients with TDR and fully active cART and patients with TDR and non-fully active cART. The frequency of virologic failure 5 to 12 months after treatment initiation was determined. Results Prevalence of TDR was stable at a high mean level of 11.9% (198/1,667) in the HIV-1 Seroconverter Cohort without significant trend over time. Nucleotide reverse transcriptase inhibitor resistance was predominant (6.0%) and decreased significantly over time (OR = 0.92, CI = 0.87–0.98, p = 0.01). Non-nucleoside reverse transcriptase inhibitor (2.4%; OR = 1.00, CI = 0.92–1.09, p = 0.96) and protease inhibitor resistance (2.0%; OR = 0.94, CI = 0.861.03, p = 0.17) remained stable. Virologic failure was observed in 6.5% of patients with TDR receiving fully active cART, 5,6% of patients with TDR receiving non-fully active cART and 3.2% of patients without TDR. The difference between the three groups was not significant (p = 0.41). Conclusion Overall prevalence of TDR remained stable at a rather high level. No significant differences in the frequency of virologic failure were identified during first-line cART between patients with TDR and fully-active cART, patients with TDR and non-fully active cART and patients without TDR. PMID:24788613

Impact of monotherapy on HIV-1 reservoir, immune activation, and co-infection with Epstein-Barr virus

PubMed Central

Petrara, Maria Raffaella; Cattelan, Anna Maria; Sasset, Lolita; Freguja, Riccardo; Carmona, Francesco; Sanavia, Silvia; Zanchetta, Marisa; Del Bianco, Paola

2017-01-01

Objectives Although monotherapy (mART) effectiveness in maintaining viral suppression and CD4 cell count has been extensively examined in HIV-1-infected patients, its impact on HIV-1 reservoir, immune activation, microbial translocation and co-infection with Epstein-Barr Virus (EBV) is unclear. Methods This retrospective study involved 32 patients who switched to mART; patients were studied at baseline, 48 and 96 weeks after mART initiation. Thirty-two patients who continued combined antiretroviral therapy (cART) over the same period of time were included in the study. Markers of HIV-1 reservoir (HIV-1 DNA and intracellular HIV-1 RNA) were quantified by real-time PCR. Markers of T-(CD3+CD8+CD38+) and B-(CD19+CD80/86+ and CD19+CD10-CD21lowCD27+) cell activation were evaluated by flow cytometry. Plasma levels of microbial translocation markers were quantified by real-time PCR (16S ribosomal DNA and mitochondrial [mt]DNA) or by ELISA (LPS and sCD14). EBV was typed and quantified by multiplex real-time PCR. Results At baseline, no differences were found between mART and cART groups. Three (10%) mART-treated patients had a virological failure vs none in the cART group. Levels of HIV-1 DNA, intracellular HIV-1 RNA and EBV-DNA remained stable in the mART group, while decreased significantly in the cART group. Percentages of T- and B-activated cells significantly increased in the mART-treated patients, while remained at low levels in the cART-treated ones (p = 0.014 and p<0.001, respectively). Notably, levels of mtDNA remained stable in the cART group, but significantly rose in the mART one (p<0.001). Conclusions Long-term mART is associated with higher levels of T- and B-cell activation and, conversely to cART, does not reduce the size of HIV-1 reservoir and EBV co-infection. PMID:28926641

MTCL1 crosslinks and stabilizes non-centrosomal microtubules on the Golgi membrane.

PubMed

Sato, Yoshinori; Hayashi, Kenji; Amano, Yoshiko; Takahashi, Mikiko; Yonemura, Shigenobu; Hayashi, Ikuko; Hirose, Hiroko; Ohno, Shigeo; Suzuki, Atsushi

2014-11-04

Recent studies have revealed the presence of a microtubule subpopulation called Golgi-derived microtubules that support Golgi ribbon formation, which is required for maintaining polarized cell migration. CLASPs and AKAP450/CG-NAP are involved in their formation, but the underlying molecular mechanisms remain unclear. Here, we find that the microtubule-crosslinking protein, MTCL1, is recruited to the Golgi membranes through interactions with CLASPs and AKAP450/CG-NAP, and promotes microtubule growth from the Golgi membrane. Correspondingly, MTCL1 knockdown specifically impairs the formation of the stable perinuclear microtubule network to which the Golgi ribbon tethers and extends. Rescue experiments demonstrate that besides its crosslinking activity mediated by the N-terminal microtubule-binding region, the C-terminal microtubule-binding region plays essential roles in these MTCL1 functions through a novel microtubule-stabilizing activity. These results suggest that MTCL1 cooperates with CLASPs and AKAP450/CG-NAP in the formation of the Golgi-derived microtubules, and mediates their development into a stable microtubule network.

Termination of T cell priming relies on a phase of unresponsiveness promoting disengagement from APCs and T cell division.

PubMed

Bohineust, Armelle; Garcia, Zacarias; Beuneu, Hélène; Lemaître, Fabrice; Bousso, Philippe

2018-05-07

T cells are primed in secondary lymphoid organs by establishing stable interactions with antigen-presenting cells (APCs). However, the cellular mechanisms underlying the termination of T cell priming and the initiation of clonal expansion remain largely unknown. Using intravital imaging, we observed that T cells typically divide without being associated to APCs. Supporting these findings, we demonstrate that recently activated T cells have an intrinsic defect in establishing stable contacts with APCs, a feature that was reflected by a blunted capacity to stop upon T cell receptor (TCR) engagement. T cell unresponsiveness was caused, in part, by a general block in extracellular calcium entry. Forcing TCR signals in activated T cells antagonized cell division, suggesting that T cell hyporesponsiveness acts as a safeguard mechanism against signals detrimental to mitosis. We propose that transient unresponsiveness represents an essential phase of T cell priming that promotes T cell disengagement from APCs and favors effective clonal expansion. © 2018 Bohineust et al.

Stable metal–organic framework-supported niobium catalysts

DOE PAGES

Ahn, Sol; Thornburg, Nicholas E.; Li, Zhanyong; ...

2016-10-31

In this study by developing structurally well-defined, supported oxide catalysts remains a significant challenge. Here, we report the grafting of Nb(V) oxide sites onto the nodes of the Zr-based metal organic framework (MOF) NU-1000 as a stable, well-defined catalyst support. Nb(V) oxide was deposited with loadings up to 1.6 mmol/g via two post-synthetic methods: atomic layer deposition in a MOF (AIM), and solution-phase grafting in a MOF (SIM). Difference envelope density (DED) measurements indicated that the two synthetic methods resulted in different local structures of the Nb(V) ions within NU-1000. Despite their high Nb(V) loadings, which were equivalent to >60%more » surface coverage, nearly all Nb(V) sites of the MOF-supported catalysts were active sites for alkene epoxidation, as confirmed by phenylphosphonic acid titration. The MOF-supported catalysts were more selective than the control Nb-ZrO 2 catalyst for cyclohexene epoxidation with aqueous H 2O 2, and were far more active on a gravimetric basis.« less

Stable Concentrated Emulsions of the 1-Monoglyceride of Capric Acid (Monocaprin) with Microbicidal Activities against the Food-Borne Bacteria Campylobacter jejuni, Salmonella spp., and Escherichia coli

PubMed Central

Thormar, Halldor; Hilmarsson, Hilmar; Bergsson, Gudmundur

2006-01-01

Of 11 fatty acids and monoglycerides tested against Campylobacter jejuni, the 1-monoglyceride of capric acid (monocaprin) was the most active in killing the bacterium. Various monocaprin-in-water emulsions were prepared which were stable after storage at room temperature for many months and which retained their microbicidal activity. A procedure was developed to manufacture up to 500 ml of 200 mM preconcentrated emulsions of monocaprin in tap water. The concentrates were clear and remained stable for at least 12 months. They were active against C. jejuni upon 160- to 200-fold dilution in tap water and caused a >6- to 7-log10 reduction in viable bacterial count in 1 min at room temperature. The addition of 0.8% Tween 40 to the concentrates as an emulsifying agent did not change the microbicidal activity. Emulsions of monocaprin killed a variety of Campylobacter isolates from humans and poultry and also killed strains of Campylobacter coli and Campylobacter lari, indicating a broad anticampylobacter activity. Emulsions of 1.25 mM monocaprin in citrate-lactate buffer at pH 4 to 5 caused a >6- to 7-log10 reduction in viable bacterial counts of Salmonella spp. and Escherichia coli in 10 min. C. jejuni was also more susceptible to monocaprin emulsions at low pH. The addition of 5 and 10 mM monocaprin emulsions to Campylobacter-spiked chicken feed significantly reduced the bacterial contamination. These results are discussed in view of the possible utilization of monocaprin emulsions in controlling the spread of food-borne bacteria from poultry to humans. PMID:16391087

Population trends, reproductive success, and organochlorine chemical contaminants in waterbirds nesting in Galveston Bay, Texas

USGS Publications Warehouse

King, K.A.; Krynitsky, A.J.

1986-01-01

The effects of environmental contaminants on the reproductive success of olivaceous cormorants (Phalacrocorax olivaceus ), Laughing gulls (Larus atricilla ), and black skimmers (Rhynchops niger ) nesting in Galveston Bay, Texas were investigated from 1980 through 1982. Populations of cormorants and gulls have remained stable in recent years, but skimmer numbers may have declined. Cormorants produced 1.9 to 2.8 young per pair in nests that remained active throughout the season. Gull and skimmer reproduction was seriously limited by storms and predation. DDE and polychlorinated biphenyl (PCB) residues in carcasses and eggs generally were below levels associated with chronic poisoning and reproductive problems in most species of birds.

MORPHOLOGICAL CELL TRANSFORMATION OF C3H10T1/2CL8 MOUSE EMBRYO CELLS BY THE K-REGION DIHYDRODIOL OF BENZO[A]PYRENE OCCURS IN COINCIDENCE WITH DNA DAMAGE, BUT WITHOUT THE FORMATION OF DETECTABLE STABLE COVALENT DNA ADDUCTS

EPA Science Inventory

Abstract:

Benzo[a]pyrene (B[a]P) has been the most thoroughly studied polycyclic aromatic hydrocarbon (PAH). Many mechanisms have been suggested to explain its carcinogenic activity, yet many questions still remain. K-region diols of PAHs are common metabolic inter...

Supramolecular Approaches to Nanoscale Morphological Control in Organic Solar Cells

PubMed Central

Haruk, Alexander M.; Mativetsky, Jeffrey M.

2015-01-01

Having recently surpassed 10% efficiency, solar cells based on organic molecules are poised to become a viable low-cost clean energy source with the added advantages of mechanical flexibility and light weight. The best-performing organic solar cells rely on a nanostructured active layer morphology consisting of a complex organization of electron donating and electron accepting molecules. Although much progress has been made in designing new donor and acceptor molecules, rational control over active layer morphology remains a central challenge. Long-term device stability is another important consideration that needs to be addressed. This review highlights supramolecular strategies for generating highly stable nanostructured organic photovoltaic active materials by design. PMID:26110382

Longitudinal changes in health related quality of life in children with migrant backgrounds.

PubMed

Villalonga-Olives, Ester; Kawachi, Ichiro; Almansa, Josue; von Steinbüchel, Nicole

2017-01-01

Little is known about longitudinal changes in the Health Related Quality of Life (HRQoL) among children with migrant backgrounds. The sample comprised 350 children with predominantly migrant backgrounds enrolled in 7 kindergartens in Frankfurt and Darmstadt, Germany. At baseline, the participants' mean age was 4.4 years (SD 0.9). Data collection started in May 2009. Two waves of data were collected one year apart (94% response rate). HRQoL was evaluated with the Kiddy-KINDL. The other variables under study were sex, age, socioeconomic status, country of origin, developmental status (WET) and individual behavior (VBV). Data were collected from the children, parents and teachers. Structural equation modeling (SEM) was used to assess the Wilson and Cleary theoretical framework on changes in HRQoL and Generalized Estimated Equations (GEE) to model the longitudinal trend in HRQoL. Overall HRQoL remained stable between baseline and follow-up. SEM model fit was χ2 = 8.51; df = 5; p = 0.13; SRMR = 0.02 RMSEA = 0.06 and indicated that there were differences in kindergarten activities (p<0.05). The GEE model elucidated that the differences in HRQoL between the baseline and follow-up varied according to kindergarten activities that the children were assigned to (music, art, or no activities) (p<0.05), but that there were no differences in terms of country of origin. On average, girls reported better HRQoL. Overall HRQoL scores remained stable over follow-up in a sample of migrant children and there were no differences in terms of origin. However, there was heterogeneity in the results depending on the kindergarten activities that the children were assigned to.

Public health strategies promoting physical activity and healthy eating in Canada: are we changing paradigms?

PubMed

Maximova, Katerina; Hanusaik, Nancy; Kishchuk, Natalie; Paradis, Gilles; O'Loughlin, Jennifer L

2016-06-01

To compare the extent to which Canadian public health organizations incorporated the Ottawa Charter for Health Promotion action areas in promoting physical activity and healthy eating in 2004 and 2010. Data were available from repeat censuses of all regional, provincial, and national organizations with mandates to promote physical activity [n = 134 (2004); n = 118 (2010)] or healthy eating [n = 137 (2004); n = 130 (2010)]. Eleven strategies to promote these behaviors were grouped according to the five action areas. Descriptive analyses were conducted to document the level of involvement in each action area over time. The proportion of organizations promoting physical activity and "heavily involved" in creating supportive environments increased from 51 % (2004) to 70 % (2010). The proportion also increased for reorienting health services (29 % to 39 %). The proportion of organizations promoting healthy eating and "heavily involved" in building healthy public policy increased from 47 to 53 %. Individual skill building remained stable for physical activity but declined for healthy eating. While developing personal skills remains important in promoting physical activity and healthy eating in Canada, public health organizations increased involvement in structural-level strategies.

GTSE1 tunes microtubule stability for chromosome alignment and segregation by inhibiting the microtubule depolymerase MCAK

PubMed Central

Bendre, Shweta; Hall, Conrad; Lin, Yu-Chih

2016-01-01

The dynamic regulation of microtubules (MTs) during mitosis is critical for accurate chromosome segregation and genome stability. Cancer cell lines with hyperstabilized kinetochore MTs have increased segregation errors and elevated chromosomal instability (CIN), but the genetic defects responsible remain largely unknown. The MT depolymerase MCAK (mitotic centromere-associated kinesin) can influence CIN through its impact on MT stability, but how its potent activity is controlled in cells remains unclear. In this study, we show that GTSE1, a protein found overexpressed in aneuploid cancer cell lines and tumors, regulates MT stability during mitosis by inhibiting MCAK MT depolymerase activity. Cells lacking GTSE1 have defects in chromosome alignment and spindle positioning as a result of MT instability caused by excess MCAK activity. Reducing GTSE1 levels in CIN cancer cell lines reduces chromosome missegregation defects, whereas artificially inducing GTSE1 levels in chromosomally stable cells elevates chromosome missegregation and CIN. Thus, GTSE1 inhibition of MCAK activity regulates the balance of MT stability that determines the fidelity of chromosome alignment, segregation, and chromosomal stability. PMID:27881713

Intestinal receptor for heat-stable enterotoxin of Escherichia coli is tightly coupled to a novel form of particulate guanylate cyclase.

PubMed Central

Waldman, S A; Kuno, T; Kamisaki, Y; Chang, L Y; Gariepy, J; O'Hanley, P; Schoolnik, G; Murad, F

1986-01-01

A novel form of particulate guanylate cyclase tightly coupled by cytoskeletal components to receptors for heat-stable enterotoxin (ST) produced by Escherichia coli can be found in membranes from rat intestinal mucosa. Intestinal particulate guanylate cyclase was resistant to solubilization with detergent alone, with only 30% of the total enzyme activity being extracted with Lubrol-PX. Under similar conditions, 70% of this enzyme was solubilized from rat lung membranes. The addition of high concentrations of sodium chloride to the extraction buffer resulted in greater solubilization of particulate guanylate cyclase from intestinal membranes. Although extraction of intestinal membranes with detergent and salt resulted in greater solubilization of guanylate cyclase, a small fraction of the enzyme activity remained associated with the particulate fraction. This activity was completely resistant to solubilization with a variety of detergents and chaotropes. Particulate guanylate cyclase and the ST receptor solubilized by detergent retained their abilities to produce cyclic GMP and bind ST, respectively. However, ST failed to activate particulate guanylate cyclase in detergent extracts. In contrast, guanylate cyclase resistant to solubilization remained functional and coupled to the ST receptor since enzyme activation by ST was unaffected by various extraction procedures. The possibility that the ST receptor and particulate guanylate cyclase were the same molecule was explored. ST binding and cyclic GMP production were separated by affinity chromatography on GTP-agarose. Similarly, guanylate cyclase migrated as a 300,000-dalton protein, while the ST receptor migrated as a 240,000-dalton protein on gel filtration chromatography. Also, thiol-reactive agents such as cystamine and N-ethylmaleimide inhibited guanylate cyclase activation by ST, with no effect on receptor binding of ST. These data suggest that guanylate cyclase and the ST receptor are independent proteins coupled by cytoskeletal components in membranes of intestinal mucosa. PMID:2867046

Match-to-match variation in physical activity and technical skill measures in professional Australian Football.

PubMed

Kempton, Thomas; Sullivan, Courtney; Bilsborough, Johann C; Cordy, Justin; Coutts, Aaron J

2015-01-01

To determine the match-to-match variability in physical activity and technical performance measures in Australian Football, and examine the influence of playing position, time of season, and different seasons on these measures of variability. Longitudinal observational study. Global positioning system, accelerometer and technical performance measures (total kicks, handballs, possessions and Champion Data rank) were collected from 33 players competing in the Australian Football League over 31 matches during 2011-2012 (N=511 observations). The global positioning system data were categorised into total distance, mean speed (mmin(-1)), high-speed running (>14.4 kmh(-1)), very high-speed running (>19.9 kmh(-1)), and sprint (>23.0 kmh(-1)) distance while player load was collected from the accelerometer. The data were log transformed to provide coefficient of variation and the between subject standard deviation (expressed as percentages). Match-to-match variability was increased for higher speed activities (high-speed running, very high-speed running, sprint distance, coefficient of variation %: 13.3-28.6%) compared to global measures (speed, total distance, player load, coefficient of variation %: 5.3-9.2%). The between-match variability was relativity stable for all measures between and within AFL seasons, with only few differences between positions. Higher speed activities (high-speed running, very high-speed running, sprint distance), but excluding mean speed, total distance and player load, were all higher in the final third phase of the season compared to the start of the season. While global measures of physical performance are relatively stable, higher-speed activities and technical measures exhibit a large degree of between-match variability in Australian Football. However, these measures remain relatively stable between positions, and within and between Australian Football League seasons. Copyright © 2013 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

The aggregation and characteristics of radiation-induced defects in lithium fluoride nanocrystals

NASA Astrophysics Data System (ADS)

Voitovich, A. P.; Kalinov, V. S.; Korzhik, M. V.; Martynovich, E. F.; Runets, L. P.; Stupak, A. P.

2013-02-01

It has been established that diffusion activation energies for anion vacancies and centres ? in lithium fluoride nanocrystals are higher than those in bulk crystals. In nanocrystals, ? centres migrating in the range of the temperature close to room temperature is not observed and these centres remain stable. The ratio of centres ? and F 2 concentrations in nanocrystals is higher than in bulk crystals. A new type of colour centres, which is absent in bulk crystals, is discovered in nanocrystals.

Preschool Executive Functions, Single-Parent Status, and School Quality Predict Diverging Trajectories of Classroom Inattention in Elementary School

PubMed Central

Sasser, Tyler R.; Beekman, Charles R.; Bierman, Karen L.

2016-01-01

A sample of 356 children recruited from Head Start (58% European American, 25% African American, and 17% Hispanic; 54% girls; Mage ¼ 4.59 years) were followed longitudinally from prekindergarten through fifth grade. Latent profile analyses of teacher-rated inattention from kindergarten through third grade identified four developmental trajectories: stable low (53% of the sample), stable high (11.3%), rising over time (16.4%), and declining over time (19.3%). Children with stable low inattention had the best academic outcomes in fifth grade, and children exhibiting stable high inattention had the worst, with the others in between. Self-regulation difficulties in preschool (poor executive function skills and elevated opposition–aggression) differentiated children with rising versus stable low inattention. Elementary schools characterized by higher achievement differentiated children with declining versus stable high inattention. Boys and children from single-parent families were more likely to remain high or rise in inattention, whereas girls and children from dual-parent families were more likely to remain low or decline in inattention. PMID:25200465

Preschool executive functions, single-parent status, and school quality predict diverging trajectories of classroom inattention in elementary school.

PubMed

Sasser, Tyler R; Beekman, Charles R; Bierman, Karen L

2015-08-01

A sample of 356 children recruited from Head Start (58% European American, 25% African American, and 17% Hispanic; 54% girls; M age = 4.59 years) were followed longitudinally from prekindergarten through fifth grade. Latent profile analyses of teacher-rated inattention from kindergarten through third grade identified four developmental trajectories: stable low (53% of the sample), stable high (11.3%), rising over time (16.4%), and declining over time (19.3%). Children with stable low inattention had the best academic outcomes in fifth grade, and children exhibiting stable high inattention had the worst, with the others in between. Self-regulation difficulties in preschool (poor executive function skills and elevated opposition-aggression) differentiated children with rising versus stable low inattention. Elementary schools characterized by higher achievement differentiated children with declining versus stable high inattention. Boys and children from single-parent families were more likely to remain high or rise in inattention, whereas girls and children from dual-parent families were more likely to remain low or decline in inattention.

Isomerization of glucose into fructose by environmentally friendly Fe/β zeolite catalysts.

PubMed

Xu, Siquan; Zhang, Lei; Xiao, Kehao; Xia, Haian

2017-06-29

Herein, the environmentally friendly Fe/β zeolite for glucose isomerization to fructose in aqueous media was reported for the first time. The effects of various reaction conditions including reaction temperature, reaction time, catalyst dosage, etc. on the isomerization reaction over Fe/β zeolite were studied in detail. Under the optimized conditions, yield of fructose higher than 20% were obtained. Moreover, the Fe/β zeolite catalysts were stable and remained constant catalytic activity after five consecutive runs. The possible active Fe species for isomerization of glucose in Fe/β zeolite is also discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Stability of rotors and focal sources for human atrial fibrillation: focal impulse and rotor mapping (FIRM) of AF sources and fibrillatory conduction.

PubMed

Swarup, Vijay; Baykaner, Tina; Rostamian, Armand; Daubert, James P; Hummel, John; Krummen, David E; Trikha, Rishi; Miller, John M; Tomassoni, Gery F; Narayan, Sanjiv M

2014-12-01

Several groups report electrical rotors or focal sources that sustain atrial fibrillation (AF) after it has been triggered. However, it is difficult to separate stable from unstable activity in prior studies that examined only seconds of AF. We applied phase-based focal impulse and rotor mapping (FIRM) to study the dynamics of rotors/sources in human AF over prolonged periods of time. We prospectively mapped AF in 260 patients (169 persistent, 61 ± 12 years) at 6 centers in the FIRM registry, using baskets with 64 contact electrodes per atrium. AF was phase mapped (RhythmView, Topera, Menlo Park, CA, USA). AF propagation movies were interpreted by each operator to assess the source stability/dynamics over tens of minutes before ablation. Sources were identified in 258 of 260 of patients (99%), for 2.8 ± 1.4 sources/patient (1.8 ± 1.1 in left, 1.1 ± 0.8 in right atria). While AF sources precessed in stable regions, emanating activity including spiral waves varied from collision/fusion (fibrillatory conduction). Each source lay in stable atrial regions for 4,196 ± 6,360 cycles, with no differences between paroxysmal versus persistent AF (4,290 ± 5,847 vs. 4,150 ± 6,604; P = 0.78), or right versus left atrial sources (P = 0.26). Rotors and focal sources for human AF mapped by FIRM over prolonged time periods precess ("wobble") but remain within stable regions for thousands of cycles. Conversely, emanating activity such as spiral waves disorganize and collide with the fibrillatory milieu, explaining difficulties in using activation mapping or signal processing analyses at fixed electrodes to detect AF rotors. These results provide a rationale for targeted ablation at AF sources rather than fibrillatory spiral waves. © 2014 Wiley Periodicals, Inc.

The Activity of Cholinesterases in Diapausing and Flying Red Mason Bees Osmia bicornis (Megachilidae).

PubMed

Dmochowska-Slezak, Kamila; Zaobidna, Ewa; Domeracka, Joanna; Swiatkowska, Marta; Rusznica, Małgorzata; Zółtowska, Krystyna

2015-01-01

The red mason bee (Osmia bicornis) is a highly effective pollinator that is exposed to various xenobiotics. The organism's potential resistance to the toxic effects of xenobiotics can be determined based on cholinesterase activity. The activity of cholinesterases (ChEs) towards acetylcholine (ACh) and butyrylcholine (BCh) was determined in extracts of diapausing (between October and late March) and flying bees (May). In both males and females, enzyme activity was higher towards ACh than towards BCh. The ratio of ACh/BCh activity was determined in the range of 1.43 to 4.15 in diapausing females and 3.00 to 7.18 in diapausing males. No significant changes in ChE activity towards ACh were observed in females before December and in males before February. Enzyme activity towards ACh increased dynamically in the second half of March. Enzyme activity towards BCh remained stable in both sexes until mid-March, after which it increased significantly. Excluding mid-March, enzyme BCh activity was significantly higher in females than in males. The activity of carboxylesterase towards 4-p-nitrophenyl butyrate was determined in females to assess the involvement of non-specific esterases in the hydrolysis of choline esters. Carboxylesterase activity was low in comparison with cholinesterase activity, and it remained practically unchanged throughout diapause, suggesting that choline esters in female O. bicornis extracts were hydrolyzed mainly by acetylcholinesterases.

Body weight and body composition of depot medroxyprogesterone acetate users.

PubMed

Dal'Ava, Natália; Bahamondes, Luis; Bahamondes, M Valeria; Bottura, Bruna F; Monteiro, Ilza

2014-08-01

Weight gain is a concern with the contraceptive depot-medroxyprogesterone acetate (DMPA); however, this issue remains controversial. The objective of this study was to compare body weight (BW) and body composition (BC) in DMPA and copper intrauterine device (IUD) users at baseline and after one year of use. We enrolled new DMPA users and age and weight matched new IUD users into this prospective study. Weight and height were measured, BC (fat and lean mass) was evaluated using dual-energy X-ray absorptiometry, and physical activity was assessed at baseline and at 12 months. Student's paired t test and the Wilcoxon paired test for matched samples were used. Ninety-seven women were enrolled for the study; 26 matched pairs continued using the initial method for at least one year, and completed the baseline and 12 month assessments. An increase of 1.9 kg occurred in BW (p=.02) in DMPA users at 12 months of use, resulting from an increase in fat mass of 1.6 kg (p=.03). Weight remained stable in IUD users; however, there was an increase in lean mass at 12 months of use (p=.001). The number of women practicing physical activity increased in this group. There was a significant difference between the groups regarding the variation in the percentage of central fat (p=.04). Weight gain in the DMPA group after the first year of use resulted from an increase in fat mass. Weight remained stable in the IUD group; however, an increase in lean mass and a reduction in localized abdominal fat mass occurred, possibly because more users were practicing physical activity. There was a greater increase in body weight in DMPA users compared to TCu380A IUD users in the first year of use of the contraceptive method. Furthermore, the weight increase in users of DMPA occurred principally as the result of an increase in fat mass. Physical activity probably could increase the lean mass in the users of TCu380A IUD. Copyright © 2014 Elsevier Inc. All rights reserved.

Neandertal cannibalism and Neandertal bones used as tools in Northern Europe

PubMed Central

Rougier, Hélène; Crevecoeur, Isabelle; Beauval, Cédric; Posth, Cosimo; Flas, Damien; Wißing, Christoph; Furtwängler, Anja; Germonpré, Mietje; Gómez-Olivencia, Asier; Semal, Patrick; van der Plicht, Johannes; Bocherens, Hervé; Krause, Johannes

2016-01-01

Almost 150 years after the first identification of Neandertal skeletal material, the cognitive and symbolic abilities of these populations remain a subject of intense debate. We present 99 new Neandertal remains from the Troisième caverne of Goyet (Belgium) dated to 40,500–45,500 calBP. The remains were identified through a multidisciplinary study that combines morphometrics, taphonomy, stable isotopes, radiocarbon dating and genetic analyses. The Goyet Neandertal bones show distinctive anthropogenic modifications, which provides clear evidence for butchery activities as well as four bones having been used for retouching stone tools. In addition to being the first site to have yielded multiple Neandertal bones used as retouchers, Goyet not only provides the first unambiguous evidence of Neandertal cannibalism in Northern Europe, but also highlights considerable diversity in mortuary behaviour among the region’s late Neandertal population in the period immediately preceding their disappearance. PMID:27381450

Mitotically Stable Modification of DNA Methylation in IGF2/H19 Imprinting Control Region Is Associated with Activated Hepatic IGF2 Expression in Offspring Rats from Betaine-Supplemented Dams.

PubMed

Yang, Shu; Zhao, Nannan; Yang, Yang; Hu, Yun; Dong, Haibo; Zhao, Ruqian

2018-03-21

The growth-promoting action of betaine involves activation of GH/IGF-1 signaling, yet it remains unclear whether insulin-like growth factor 2 (IGF2), an imprinting gene, is affected by maternal dietary betaine supplementation. In this study, F1 offspring rats derived from dams fed basal or betaine-supplemented diet were examined at D21 and D63. Maternal betaine significantly upregulated the hepatic expression of IGF2 mRNA and protein in offspring rats at both D21 and D63, which was accompanied by enhanced hepatic IGF2 immunoreactivity and elevated serum IGF-2 level. Higher protein expression of betaine-homocysteine methyltransferase and DNA methyltransferase 1 was detected in the betaine group at D21, but not D63. However, hypermethylation of the imprinting control region of the IGF2/H19 locus at D21 was maintained at D63. These results indicate that maternal betaine modifies DNA methylation of IGF2/H19 imprinting control region in a mitotically stable fasion, which was associated with the activation hepatic IGF2 expression in offspring rats.

Self-organization of synchronous activity propagation in neuronal networks driven by local excitation

PubMed Central

Bayati, Mehdi; Valizadeh, Alireza; Abbassian, Abdolhossein; Cheng, Sen

2015-01-01

Many experimental and theoretical studies have suggested that the reliable propagation of synchronous neural activity is crucial for neural information processing. The propagation of synchronous firing activity in so-called synfire chains has been studied extensively in feed-forward networks of spiking neurons. However, it remains unclear how such neural activity could emerge in recurrent neuronal networks through synaptic plasticity. In this study, we investigate whether local excitation, i.e., neurons that fire at a higher frequency than the other, spontaneously active neurons in the network, can shape a network to allow for synchronous activity propagation. We use two-dimensional, locally connected and heterogeneous neuronal networks with spike-timing dependent plasticity (STDP). We find that, in our model, local excitation drives profound network changes within seconds. In the emergent network, neural activity propagates synchronously through the network. This activity originates from the site of the local excitation and propagates through the network. The synchronous activity propagation persists, even when the local excitation is removed, since it derives from the synaptic weight matrix. Importantly, once this connectivity is established it remains stable even in the presence of spontaneous activity. Our results suggest that synfire-chain-like activity can emerge in a relatively simple way in realistic neural networks by locally exciting the desired origin of the neuronal sequence. PMID:26089794

Metronidazole-triazole conjugates: Activity against Clostridium difficile and parasites

PubMed Central

Jarrad, Angie M.; Karoli, Tomislav; Debnath, Anjan; Tay, Chin Yen; Huang, Johnny X.; Kaeslin, Geraldine; Elliott, Alysha G.; Miyamoto, Yukiko; Ramu, Soumya; Kavanagh, Angela M.; Zuegg, Johannes; Eckmann, Lars; Blaskovich, Mark A.T.; Cooper, Matthew A.

2015-01-01

Metronidazole has been used clinically for over 50 years as an antiparasitic and broad-spectrum antibacterial agent effective against anaerobic bacteria. However resistance to metronidazole in parasites and bacteria has been reported, and improved second-generation metronidazole analogues are needed. The copper catalysed Huigsen azide-alkyne 1,3-dipolar cycloaddition offers a way to efficiently assemble new libraries of metronidazole analogues. Several new metronidazole-triazole conjugates (Mtz-triazoles) have been identified with excellent broad spectrum antimicrobial and antiparasitic activity targeting Clostridium difficile, Entamoeba histolytica and Giardia lamblia. Cross resistance to metronidazole was observed against stable metronidazole resistant C. difficile and G. lamblia strains. However for the most potent Mtz-triazoles, the activity remained in a therapeutically relevant window. PMID:26117821

Boron doped graphene wrapped silver nanowires as an efficient electrocatalyst for molecular oxygen reduction

NASA Astrophysics Data System (ADS)

Nair, Anju K.; Thazhe Veettil, Vineesh; Kalarikkal, Nandakumar; Thomas, Sabu; Kala, M. S.; Sahajwalla, Veena; Joshi, Rakesh K.; Alwarappan, Subbiah

2016-12-01

Metal nanowires exhibit unusually high catalytic activity towards oxygen reduction reaction (ORR) due to their inherent electronic structures. However, controllable synthesis of stable nanowires still remains as a daunting challenge. Herein, we report the in situ synthesis of silver nanowires (AgNWs) over boron doped graphene sheets (BG) and demonstrated its efficient electrocatalytic activity towards ORR for the first time. The electrocatalytic ORR efficacy of BG-AgNW is studied using various voltammetric techniques. The BG wrapped AgNWs shows excellent ORR activity, with very high onset potential and current density and it followed four electron transfer mechanism with high methanol tolerance and stability towards ORR. The results are comparable to the commercially available 20% Pt/C in terms of performance.

Effects of tethering a multistate folding protein to a surface

NASA Astrophysics Data System (ADS)

Wei, Shuai; Knotts, Thomas A.

2011-05-01

Protein/surface interactions are important in a variety of fields and devices, yet fundamental understanding of the relevant phenomena remains fragmented due to resolution limitations of experimental techniques. Molecular simulation has provided useful answers, but such studies have focused on proteins that fold through a two-state process. This study uses simulation to show how surfaces can affect proteins which fold through a multistate process by investigating the folding mechanism of lysozyme (PDB ID: 7LZM). The results demonstrate that in the bulk 7LZM folds through a process with four stable states: the folded state, the unfolded state, and two stable intermediates. The folding mechanism remains the same when the protein is tethered to a surface at most residues; however, in one case the folding mechanism changes in such a way as to eliminate one of the intermediates. An analysis of the molecular configurations shows that tethering at this site is advantageous for protein arrays because the active site is both presented to the bulk phase and stabilized. Taken as a whole, the results offer hope that rational design of protein arrays is possible once the behavior of the protein on the surface is ascertained.

Protein expression changes caused by spaceflight as measured for 18 Russian cosmonauts.

PubMed

M Larina, Irina; Percy, Andrew J; Yang, Juncong; Borchers, Christoph H; M Nosovsky, Andrei; I Grigoriev, Anatoli; N Nikolaev, Evgeny

2017-08-15

The effects of spaceflight on human physiology is an increasingly studied field, yet the molecular mechanisms driving physiological changes remain unknown. With that in mind, this study was performed to obtain a deeper understanding of changes to the human proteome during space travel, by quantitating a panel of 125 proteins in the blood plasma of 18 Russian cosmonauts who had conducted long-duration missions to the International Space Station. The panel of labeled prototypic tryptic peptides from these proteins covered a concentration range of more than 5 orders of magnitude in human plasma. Quantitation was achieved by a well-established and highly-regarded targeted mass spectrometry approach involving multiple reaction monitoring in conjunction with stable isotope-labeled standards. Linear discriminant function analysis of the quantitative results revealed three distinct groups of proteins: 1) proteins with post-flight protein concentrations remaining stable, 2) proteins whose concentrations recovered slowly, or 3) proteins whose concentrations recovered rapidly to their pre-flight levels. Using a systems biology approach, nearly all of the reacting proteins could be linked to pathways that regulate the activities of proteases, natural immunity, lipid metabolism, coagulation cascades, or extracellular matrix metabolism.

An intermittent control model of flexible human gait using a stable manifold of saddle-type unstable limit cycle dynamics

PubMed Central

Fu, Chunjiang; Suzuki, Yasuyuki; Kiyono, Ken; Morasso, Pietro; Nomura, Taishin

2014-01-01

Stability of human gait is the ability to maintain upright posture during walking against external perturbations. It is a complex process determined by a number of cross-related factors, including gait trajectory, joint impedance and neural control strategies. Here, we consider a control strategy that can achieve stable steady-state periodic gait while maintaining joint flexibility with the lowest possible joint impedance. To this end, we carried out a simulation study of a heel-toe footed biped model with hip, knee and ankle joints and a heavy head-arms-trunk element, working in the sagittal plane. For simplicity, the model assumes a periodic desired joint angle trajectory and joint torques generated by a set of feed-forward and proportional-derivative feedback controllers, whereby the joint impedance is parametrized by the feedback gains. We could show that a desired steady-state gait accompanied by the desired joint angle trajectory can be established as a stable limit cycle (LC) for the feedback controller with an appropriate set of large feedback gains. Moreover, as the feedback gains are decreased for lowering the joint stiffness, stability of the LC is lost only in a few dimensions, while leaving the remaining large number of dimensions quite stable: this means that the LC becomes saddle-type, with a low-dimensional unstable manifold and a high-dimensional stable manifold. Remarkably, the unstable manifold remains of low dimensionality even when the feedback gains are decreased far below the instability point. We then developed an intermittent neural feedback controller that is activated only for short periods of time at an optimal phase of each gait stride. We characterized the robustness of this design by showing that it can better stabilize the unstable LC with small feedback gains, leading to a flexible gait, and in particular we demonstrated that such an intermittent controller performs better if it drives the state point to the stable manifold, rather than directly to the LC. The proposed intermittent control strategy might have a high affinity for the inverted pendulum analogy of biped gait, providing a dynamic view of how the step-to-step transition from one pendular stance to the next can be achieved stably in a robust manner by a well-timed neural intervention that exploits the stable modes embedded in the unstable dynamics. PMID:25339687

An intermittent control model of flexible human gait using a stable manifold of saddle-type unstable limit cycle dynamics.

PubMed

Fu, Chunjiang; Suzuki, Yasuyuki; Kiyono, Ken; Morasso, Pietro; Nomura, Taishin

2014-12-06

Stability of human gait is the ability to maintain upright posture during walking against external perturbations. It is a complex process determined by a number of cross-related factors, including gait trajectory, joint impedance and neural control strategies. Here, we consider a control strategy that can achieve stable steady-state periodic gait while maintaining joint flexibility with the lowest possible joint impedance. To this end, we carried out a simulation study of a heel-toe footed biped model with hip, knee and ankle joints and a heavy head-arms-trunk element, working in the sagittal plane. For simplicity, the model assumes a periodic desired joint angle trajectory and joint torques generated by a set of feed-forward and proportional-derivative feedback controllers, whereby the joint impedance is parametrized by the feedback gains. We could show that a desired steady-state gait accompanied by the desired joint angle trajectory can be established as a stable limit cycle (LC) for the feedback controller with an appropriate set of large feedback gains. Moreover, as the feedback gains are decreased for lowering the joint stiffness, stability of the LC is lost only in a few dimensions, while leaving the remaining large number of dimensions quite stable: this means that the LC becomes saddle-type, with a low-dimensional unstable manifold and a high-dimensional stable manifold. Remarkably, the unstable manifold remains of low dimensionality even when the feedback gains are decreased far below the instability point. We then developed an intermittent neural feedback controller that is activated only for short periods of time at an optimal phase of each gait stride. We characterized the robustness of this design by showing that it can better stabilize the unstable LC with small feedback gains, leading to a flexible gait, and in particular we demonstrated that such an intermittent controller performs better if it drives the state point to the stable manifold, rather than directly to the LC. The proposed intermittent control strategy might have a high affinity for the inverted pendulum analogy of biped gait, providing a dynamic view of how the step-to-step transition from one pendular stance to the next can be achieved stably in a robust manner by a well-timed neural intervention that exploits the stable modes embedded in the unstable dynamics.

Dual-radiolabeled nanoparticle probes for depth-independent in vivo imaging of enzyme activation

NASA Astrophysics Data System (ADS)

Black, Kvar C. L.; Zhou, Mingzhou; Sarder, Pinaki; Kuchuk, Maryna; Al-Yasiri, Amal Y.; Gunsten, Sean P.; Liang, Kexian; Hennkens, Heather M.; Akers, Walter J.; Laforest, Richard; Brody, Steven L.; Cutler, Cathy S.; Achilefu, Samuel

2018-02-01

Quantitative and noninvasive measurement of protease activities has remained an imaging challenge in deep tissues such as the lungs. Here, we designed a dual-radiolabeled probe for reporting the activities of proteases such as matrix metalloproteinases (MMPs) with multispectral single photon emission computed tomography (SPECT) imaging. A gold nanoparticle (NP) was radiolabeled with 125I and 111In and functionalized with an MMP9-cleavable peptide to form a multispectral SPECT imaging contrast agent. In another design, incorporation of 199Au radionuclide into the metal crystal structure of gold NPs provided a superior and stable reference signal in lungs, and 111In was linked to the NP surface via a protease-cleavable substrate, which can serve as an enzyme activity reporter. This work reveals strategies to correlate protease activities with diverse pathologies in a tissue-depth independent manner.

Akt Suppression of TGFβ Signaling Contributes to the Maintenance of Vascular Identity in Embryonic Stem Cell-Derived Endothelial Cells

PubMed Central

Israely, Edo; Ginsberg, Michael; Nolan, Daniel; Ding, Bi-Sen; James, Daylon; Elemento, Olivier; Rafii, Shahin; Rabbany, Sina Y

2016-01-01

The ability to generate and maintain stable in vitro cultures of mouse endothelial cells (EC) has great potential for genetic dissection of the numerous pathologies involving vascular dysfunction as well as therapeutic applications. However, previous efforts at achieving sustained cultures of primary stable murine vascular cells have fallen short, and the cellular requirements for EC maintenance in vitro remain undefined. In this study, we have generated vascular ECs from mouse embryonic stem (ES) cells, and show that active Akt is essential to their survival and propagation as homogeneous monolayers in vitro. These cells harbor the phenotypical, biochemical, and functional characteristics of ECs, and expand throughout long-term cultures, while maintaining their angiogenic capacity. Moreover, Akt-transduced embryonic ECs form functional perfused vessels in vivo that anastomose with host blood vessels. We provide evidence for a novel function of Akt in stabilizing EC identity, whereby the activated form of the protein protects mouse ES cell-derived ECs from TGFβ-mediated transdifferentiation by downregulating SMAD3. These findings identify a role for Akt in regulating the developmental potential of ES cell-derived ECs, and demonstrate that active Akt maintains endothelial identity in embryonic ECs by interfering with active TGFβ-mediated processes that would ordinarily usher these cells to alternate fates. PMID:23963623

The unique GH5 cellulase member in the extreme halotolerant fungus Aspergillus glaucus CCHA is an endoglucanase with multiple tolerance to salt, alkali and heat: prospects for straw degradation applications.

PubMed

Li, Zhengqun; Pei, Xue; Zhang, Ziyu; Wei, Yi; Song, Yanyue; Chen, Lina; Liu, Shouan; Zhang, Shi-Hong

2018-07-01

In a halotolerant fungus Aspergillus glaucus CCHA, several functional proteins with stress-tolerant activity have been studied, but no secretory enzymes have been identified yet. The unique GH5 cellulase candidate from A. glaucus, an endoglucanase termed as AgCMCase, was cloned, expressed in the Pichia pastoris system and the purified enzyme was characterized. A large amount of recombinant enzyme secreted by the P. pastoris GS115 strain was purified to homogeneity. The molecular weight of the purified endoglucanase is about 55.0 kDa. The AgCMCase exhibited optimum catalytic activity at pH 5.0 and 55 °C. However, it remained relatively stable at temperatures ranging from 45 to 80 °C and pH ranging from 4.0 to 9.0. In addition, it showed higher activity at extreme NaCl concentrations from 1.0 to 4.0 M, suggesting it is an enzyme highly stable under heat, acid, alkaline and saline conditions. To evaluate the catalytic activity of AgCMCase, the hydrolysis products of rice and corn straws were successfully studied. In conclusion, the AgCMCase is a thermostable and salt-tolerant cellulase with potential for industrial application.

Akt suppression of TGFβ signaling contributes to the maintenance of vascular identity in embryonic stem cell-derived endothelial cells.

PubMed

Israely, Edo; Ginsberg, Michael; Nolan, Daniel; Ding, Bi-Sen; James, Daylon; Elemento, Olivier; Rafii, Shahin; Rabbany, Sina Y

2014-01-01

The ability to generate and maintain stable in vitro cultures of mouse endothelial cells (ECs) has great potential for genetic dissection of the numerous pathologies involving vascular dysfunction as well as therapeutic applications. However, previous efforts at achieving sustained cultures of primary stable murine vascular cells have fallen short, and the cellular requirements for EC maintenance in vitro remain undefined. In this study, we have generated vascular ECs from mouse embryonic stem (ES) cells and show that active Akt is essential to their survival and propagation as homogeneous monolayers in vitro. These cells harbor the phenotypical, biochemical, and functional characteristics of ECs and expand throughout long-term cultures, while maintaining their angiogenic capacity. Moreover, Akt-transduced embryonic ECs form functional perfused vessels in vivo that anastomose with host blood vessels. We provide evidence for a novel function of Akt in stabilizing EC identity, whereby the activated form of the protein protects mouse ES cell-derived ECs from TGFβ-mediated transdifferentiation by downregulating SMAD3. These findings identify a role for Akt in regulating the developmental potential of ES cell-derived ECs and demonstrate that active Akt maintains endothelial identity in embryonic ECs by interfering with active TGFβ-mediated processes that would ordinarily usher these cells to alternate fates. © AlphaMed Press.

Stereoselective Syntheses of Soman Analog

DTIC Science & Technology

1993-04-28

only one pseudorotatomer cycle exists. Surprisingly. la-f are hydrolytically stable in the absence of acid ; phosphorane lb, for example, remained...unchanged in CDCl3 for at least 2 weeks even in the presence of water or 0.1 N NaOH at room temperature. However, la-f are extremely labile to aqueous acids ...1 and 2 are hydrolytically stable in neutral and basic conditions, but extremely labile to aqueous acids : they remained unchanged for at least 3 days

Use of stable isotope-labelled cells to identify active grazers of picocyanobacteria in ocean surface waters.

PubMed

Frias-Lopez, Jorge; Thompson, Anne; Waldbauer, Jacob; Chisholm, Sallie W

2009-02-01

Prochlorococcus and Synechococcus are the two most abundant marine cyanobacteria. They represent a significant fraction of the total primary production of the world oceans and comprise a major fraction of the prey biomass available to phagotrophic protists. Despite relatively rapid growth rates, picocyanobacterial cell densities in open-ocean surface waters remain fairly constant, implying steady mortality due to viral infection and consumption by predators. There have been several studies on grazing by specific protists on Prochlorococcus and Synechococcus in culture, and of cell loss rates due to overall grazing in the field. However, the specific sources of mortality of these primary producers in the wild remain unknown. Here, we use a modification of the RNA stable isotope probing technique (RNA-SIP), which involves adding labelled cells to natural seawater, to identify active predators that are specifically consuming Prochlorococcus and Synechococcus in the surface waters of the Pacific Ocean. Four major groups were identified as having their 18S rRNA highly labelled: Prymnesiophyceae (Haptophyta), Dictyochophyceae (Stramenopiles), Bolidomonas (Stramenopiles) and Dinoflagellata (Alveolata). For the first three of these, the closest relative of the sequences identified was a photosynthetic organism, indicating the presence of mixotrophs among picocyanobacterial predators. We conclude that the use of RNA-SIP is a useful method to identity specific predators for picocyanobacteria in situ, and that the method could possibly be used to identify other bacterial predators important in the microbial food-web.

Characterization of Lactobacillus salivarius strains B37 and B60 capable of inhibiting IL-8 production in Helicobacter pylori-stimulated gastric epithelial cells.

PubMed

Panpetch, Wimonrat; Spinler, Jennifer K; Versalovic, James; Tumwasorn, Somying

2016-10-18

Interleukin (IL)-8 is the key agent for initiating an inflammatory response to infection with Helicobacter pylori. Some strains of Lactobacillus spp. are known to colonize the stomach and suppress inflammation caused by H. pylori. In this study, we characterized two gastric-derived lactobacilli, Lactobacillus salivarius (LS) strains B37 and B60, capable of inhibiting H. pylori-induced IL-8 production by gastric epithelial cells. Conditioned media from LS-B37 and LS-B60 suppressed H. pylori-induced IL-8 production and mRNA expression from AGS cells without inhibiting H. pylori growth. These conditioned media suppressed the activation of NF-κB but did not suppress c-Jun activation. IL-8 inhibitory substances in conditioned media of LS-B37 and LS-B60 are heat-stable and larger than 100 kDa in size. The inhibitory activity of LS-B37 was abolished when the conditioned medium was treated with α-amylase but still remained when treated with either proteinase K, trypsin, lipase or lysozyme. The activity of LS-B60 was abolished when the conditioned medium was treated with either amylase or proteinase K but still remained when treated with lysozyme. Treatment with lipase and trypsin also significantly affected the inhibitory activity of LS-B60 although the conditioned medium retained IL-8 suppression statistically different from media control. These results suggest that L. salivarius strains B37 and B60 produce different immunomodulatory factors capable of suppressing H. pylori-induced IL-8 production from gastric epithelial cells. Our results suggest that the large, heat-stable immunomodulatory substance(s) present in the LCM of LS-B37 is a polysaccharide, while the one(s) of LS-B60 is either complex consisting of components of polysaccharide, lipid and protein or includes multiple components such as glycoprotein and lipoprotein.

Highly stable noble-metal nanoparticles in tetraalkylphosphonium ionic liquids for in situ catalysis.

PubMed

Banerjee, Abhinandan; Theron, Robin; Scott, Robert W J

2012-01-09

Gold and palladium nanoparticles were prepared by lithium borohydride reduction of the metal salt precursors in tetraalkylphosphonium halide ionic liquids in the absence of any organic solvents or external nanoparticle stabilizers. These colloidal suspensions remained stable and showed no nanoparticle agglomeration over many months. A combination of electrostatic interactions between the coordinatively unsaturated metal nanoparticle surface and the ionic-liquid anions, bolstered by steric protection offered by the bulky alkylated phosphonium cations, is likely to be the reason behind such stabilization. The halide anion strongly absorbs to the nanoparticle surface, leading to exceptional nanoparticle stability in halide ionic liquids; other tetraalkylphosphonium ionic liquids with non-coordinating anions, such as tosylate and hexafluorophosphate, show considerably lower affinities towards the stabilization of nanoparticles. Palladium nanoparticles stabilized in the tetraalkylphosphonium halide ionic liquid were stable, efficient, and recyclable catalysts for a variety of hydrogenation reactions at ambient pressures with sustained activity. Aerial oxidation of the metal nanoparticles occurred over time and was readily reversed by re-reduction of oxidized metal salts. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Vacancy clustering and acceptor activation in nitrogen-implanted ZnO

NASA Astrophysics Data System (ADS)

Børseth, Thomas Moe; Tuomisto, Filip; Christensen, Jens S.; Monakhov, Edouard V.; Svensson, Bengt G.; Kuznetsov, Andrej Yu.

2008-01-01

The role of vacancy clustering and acceptor activation on resistivity evolution in N ion-implanted n -type hydrothermally grown bulk ZnO has been investigated by positron annihilation spectroscopy, resistivity measurements, and chemical profiling. Room temperature 220keV N implantation using doses in the low 1015cm-2 range induces small and big vacancy clusters containing at least 2 and 3-4 Zn vacancies, respectively. The small clusters are present already in as-implanted samples and remain stable up to 1000°C with no significant effect on the resistivity evolution. In contrast, formation of the big clusters at 600°C is associated with a significant increase in the free electron concentration attributed to gettering of amphoteric Li impurities by these clusters. Further annealing at 800°C results in a dramatic decrease in the free electron concentration correlated with activation of 1016-1017cm-3 acceptors likely to be N and/or Li related. The samples remain n type, however, and further annealing at 1000°C results in passivation of the acceptor states while the big clusters dissociate.

Course of chronic hilar sarcoidosis in relation to markers of granulomatous activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Israel, H.L.; Sperber, M.; Steiner, R.M.

Studies of the course of sarcoidosis have emphasized that patients with hilar or mediastinal adenopathy usually recover within several years or develop dissemination to the lungs. Chronic hilar and mediastinal adenopathy persisting with little or no change for many decades is an important subgroup that has not received adequate attention. Twelve such patients have been studied. Seven remained asymptomatic, despite persistent adenopathy, for a mean period of 16 years; two with disfiguring facial sarcoids received corticosteroids for 18 and 27 years, respectively, and three patients after ten years of stable adenopathy developed pulmonary infiltrates. Tests performed on patients with hilarmore » adenopathy to evaluate cellular activity after a mean interval of over 16 years included Kveim reaction (positive in nine of ten), serum angiotensin converting enzyme (elevated in eight of 12), and gallium-67 scanning (hilar uptake in all eight tested). Results were similar for patients who remained well and for those who had symptomatic or progressive disease, indicating that these parameters of granulomatous activity do not reflect the duration of the disease, its outcome, or the need for treatment.« less

Evaluating the use of stable isotope analysis to infer the feeding ecology of a growing US gray seal (Halichoerus grypus) population.

PubMed

Lerner, Jacob E; Ono, Kathryn; Hernandez, Keith M; Runstadler, Jonathan A; Puryear, Wendy B; Polito, Michael J

2018-01-01

Gray seals (Halichoerus grypus) have been rapidly recolonizing the Northeast US coast, eliciting concern from the fishing industry. However, the ecological effect of this recovery is still unknown and as such, research is needed to better understand how the diet composition of gray seals in US waters will contribute to the ecological impact. While previous research on seal diets has focused on the analysis of hard prey remains, stable isotope analysis presents an alternative method that can be used to describe marine mammal diets when direct observation is impossible. To address this issue, we used stable isotope analysis of gray seal pup vibrissae and lanugo from Monomoy Island, Cape Cod, MA during the 2015/2016 winter breeding season to estimate adult female diet composition during pregnancy. Stable isotope mixing models (SIMM) suggested adult female gray seals were consuming greater amounts of cephalopod prey and less sand lance than previously indicated from analysis of hard prey remains. However, using SIMMs to estimate the diet composition of gray seals remains difficult due to the large number of isotopically similar prey species and uncertainty in tissue-specific, stable isotope trophic enrichment factors. Even so, by combining prey sources into ecologically informative groups and integrating prior information into SIMMs it is possible to obtain additional insights into the diet of this generalist predator.

Stable, semi-stable populations and growth potential.

PubMed

Bourgeois-Pichat, J

1971-07-01

Abstract Starting from the definition of a Malthusian population given by Alfred J. Lotka, the author recalls how the concept of stable population is introduced in demography, first as a particular case of stable populations, and secondly as a limit of a demographic evolutionary process in which female age-specific fertility rates and age-specific mortality rates remain constant. Then he defines a new concept: the semi-stable population which is a population with a constant age distribution. He shows that such a population coincides at any point of time with the stable population corresponding to the mortality and the fertility at this point of time. In the remaining part of the paper it is shown how the concept of a stable population can be used for defining a coefficient of inertia which measures the resistance of a population to modification of its course as a consequence of changing fertility and mortality. Some formulae are established to calculate this coefficient first for an arbitrary population, and secondly for a semistable population. In this second case the formula is particularly simple. It appears as a product of three terms: the expectation of life at birth in years, the crude birth rate, and a coefficient depending on the rate of growth and for which a numerical table is easy to establish.

New trends in the development of opioid peptide analogues as advanced remedies for pain relief.

PubMed

Gentilucci, Luca

2004-01-01

The search for new peptides to be used as analgesics in place of morphine has been mainly directed to develop peptide analogues or peptidomimetics having higher biological stability and receptor selectivity. Indeed, most of the alkaloid opioid counterindications are due to the scarce stability and the contemporary activation of different receptor types. However, the development of several extremely stable and selective peptide ligands for the different opioid receptors, and the recent discovery of the micro-receptor selective endomorphins, rendered this search less fundamental. In recent years, other opioid peptide properties have been investigated in the search for new pharmacological tools. The utility of a drug depends on its ability to reach appropriate receptors at the target tissue and to remain metabolically stable in order to produce the desired effect. This review deals with the recent investigations on peptide bioavailability, in particular barrier penetration and resistance against enzymatic degradation; with the development of peptides having activity at different receptors; with chimeric peptides, with propeptides, and with non-conventional peptides, lacking basic pharmacophoric features.

Incidence of Chlamydia trachomatis infections and screening compliance, U.S. Army active duty females under 25 years of age, 2011-2014.

PubMed

Tourdot, Laura E; Jordan, Nikki N; Leamer, Nicole K; Nowak, Gosia; Gaydos, Joel C

2016-02-01

Reported chlamydia infection rates among active duty U.S. Army females less than 25 years old declined by 20% from 2011 to 2014 (11,028 infections per 100,000 person-years [p-yrs] to 8,793 infections per 100,000 p-yrs, respectively). An overall decline in the proportions of high-risk female soldiers tested for chlamydia occurred during the same period, declining from a high of 85% in 2011 to a low of 71% in 2012, with an increase to 80% in 2014. Chlamydia laboratory testing volume also decreased from 2011 to 2013 but the test positivity rate remained stable at 6.0%-6.4%. By using projected incidence rates based on 100% of at-risk women being screened with a stable laboratory positivity rate, there was an estimated 15% decline in chlamydia incidence from 2011 to 2014 (12,794 to 10,991 infections per 100,000 p-yrs, respectively). Surveillance for chlamydia infections must include consideration of screening program performance in addition to passive reporting.

Characterization of a BODIPY Dye as an Active Species for Redox Flow Batteries.

PubMed

Kosswattaarachchi, Anjula M; Friedman, Alan E; Cook, Timothy R

2016-12-08

An all-organic redox flow battery (RFB) employing a fluorescent boron-dipyrromethene (BODIPY) dye (PM567) was investigated. In a RFB, the stability of the electrolyte in all charged states is critically linked to coulombic efficiency. To evaluate stability, bulk electrolysis and cyclic voltammetry (CV) experiments were performed. Oxidized and reduced, PM567 does not remain intact; however, the products of bulk electrolysis evolve over time to show stable redox behavior, making the dye a precursor for the active species of an RFB. A theoretical cell potential of 2.32 V was predicted from CV experiments with a working discharge voltage of approximately 1.6 V in a static test cell. Mass spectrometry was used to identify the products of bulk electrolysis. Related experiments were carried out using ferrocene and cobaltocenium hexafluorophosphate as redox-stable benchmarks to further explain the stability results. The coulombic efficiency of a model cell using PM567 as a precursor for charge carriers stabilized around 73 %. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

A novel nonionic surfactant- and solvent-stable alkaline serine protease from Serratia sp. SYBC H with duckweed as nitrogen source: production, purification, characteristics and application.

PubMed

Li, G Y; Cai, Y J; Liao, X R; Yin, J

2011-07-01

A novel nonionic surfactant- and hydrophilic solvent-stable alkaline serine protease was purified from the culture supernatant of Serratia sp. SYBC H with duckweed as nitrogen source. The molecular mass of the purified protease is about 59 kDa as assayed via SDS-PAGE. The protease is highly active over the pH range between 5.0 and 11.0, with the maximum activity at pH 8.0. It is also fairly active over the temperature range between 30 and 80°C, with the maximum activity at 40°C. The protease activity was substantially stimulated by Mn(2+) and Na(+) (5 mM), up to 837.9 and 134.5% at 40°C, respectively. In addition, Mn(2+) enhanced the thermostability of the protease significantly at 60°C. Over 90% of its initial activity remained even after incubating for 60 min at 40°C in 50% (v/v) hydrophilic organic solvents such as DMF, DMSO, acetone and MeOH. The protease retained 81.7, 83.6 and 76.2% of its initial activity in the presence of nonionic surfactants 20% (v/v) Tween 80, 25% (v/v) glycerol and Triton X-100, respectively. The protease is strongly inhibited by PMSF, suggesting that it is a serine protease. Washing experiments revealed that the protease has an excellent ability to remove blood stains.

Electron beam-induced immobilization of laccase on porous supports for waste water treatment applications.

PubMed

Jahangiri, Elham; Reichelt, Senta; Thomas, Isabell; Hausmann, Kristin; Schlosser, Dietmar; Schulze, Agnes

2014-08-08

The versatile oxidase enzyme laccase was immobilized on porous supports such as polymer membranes and cryogels with a view of using such biocatalysts in bioreactors aiming at the degradation of environmental pollutants in wastewater. Besides a large surface area for supporting the biocatalyst, the aforementioned porous systems also offer the possibility for simultaneous filtration applications in wastewater treatment. Herein a "green" water-based, initiator-free, and straightforward route to highly reactive membrane and cryogel-based bioreactors is presented, where laccase was immobilized onto the porous polymer supports using a water-based electron beam-initiated grafting reaction. In a second approach, the laccase redox mediators 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and syringaldehyde were cross-linked instead of the enzyme via electron irradiation in a frozen aqueous poly(acrylate) mixture in a one pot set-up, yielding a mechanical stable macroporous cryogel with interconnected pores ranging from 10 to 50 µm in size. The membranes as well as the cryogels were characterized regarding their morphology, chemical composition, and catalytic activity. The reactivity towards waste- water pollutants was demonstrated by the degradation of the model compound bisphenol A (BPA). Both membrane- and cryogel-immobilized laccase remained highly active after electron beam irradiation. Apparent specific BPA removal rates were higher for cryogel- than for membrane-immobilized and free laccase, whereas membrane-immobilized laccase was more stable with respect to maintenance of enzymatic activity and prevention of enzyme leakage from the carrier than cryogel-immobilized laccase. Cryogel-immobilized redox mediators remained functional in accelerating the laccase-catalyzed BPA degradation, and especially ABTS was found to act more efficiently in immobilized than in freely dissolved state.

Explaining pathological changes in axonal excitability through dynamical analysis of conductance-based models

NASA Astrophysics Data System (ADS)

Coggan, Jay S.; Ocker, Gabriel K.; Sejnowski, Terrence J.; Prescott, Steven A.

2011-10-01

Neurons rely on action potentials, or spikes, to relay information. Pathological changes in spike generation likely contribute to certain enigmatic features of neurological disease, like paroxysmal attacks of pain and muscle spasm. Paroxysmal symptoms are characterized by abrupt onset and short duration, and are associated with abnormal spiking although the exact pathophysiology remains unclear. To help decipher the biophysical basis for 'paroxysmal' spiking, we replicated afterdischarge (i.e. continued spiking after a brief stimulus) in a minimal conductance-based axon model. We then applied nonlinear dynamical analysis to explain the dynamical basis for initiation and termination of afterdischarge. A perturbation could abruptly switch the system between two (quasi-)stable attractor states: rest and repetitive spiking. This bistability was a consequence of slow positive feedback mediated by persistent inward current. Initiation of afterdischarge was explained by activation of the persistent inward current forcing the system to cross a saddle point that separates the basins of attraction associated with each attractor. Termination of afterdischarge was explained by the attractor associated with repetitive spiking being destroyed. This occurred when ultra-slow negative feedback, such as intracellular sodium accumulation, caused the saddle point and stable limit cycle to collide; in that regard, the active attractor is not truly stable when the slowest dynamics are taken into account. The model also explains other features of paroxysmal symptoms, including temporal summation and refractoriness.

Ag-bridged Ag2O nanowire network/TiO2 nanotube array p-n heterojunction as a highly efficient and stable visible light photocatalyst.

PubMed

Liu, Chengbin; Cao, Chenghao; Luo, Xubiao; Luo, Shenglian

2015-03-21

A unique Ag-bridged Ag2O nanowire network/TiO2 nanotube array p-n heterojunction (Ag-Ag2O/TiO2 NT) was fabricated by simple electrochemical method. Ag nanoparticles were firstly electrochemically deposited onto the surface of TiO2 NT and then were partly oxidized to Ag2O nanowires while the rest of Ag mother nanoparticles were located at the junctions of Ag2O nanowire network. The Ag-Ag2O/TiO2 NT heterostructure exhibited strong visible-light response, effective separation of photogenerated carriers, and high adsorption capacity. The integration of Ag-Ag2O self-stability structure and p-n heterojunction permitted high and stable photocatalytic activity of Ag-Ag2O/TiO2 NT heterostructure photocatalyst. Under 140-min visible light irradiation, the photocatalytic removal efficiency of both dye acid orange 7 (AO7) and industrial chemical p-nitrophenol (PNP) over Ag-Ag2O/TiO2 NT reached nearly 100% much higher than 17% for AO7 or 13% for PNP over bare TiO2 NT. After 5 successive cycles under 600-min simulated solar light irradiation, Ag-Ag2O/TiO2 NT remained highly stable photocatalytic activity. Copyright © 2014 Elsevier B.V. All rights reserved.

Stable Sequential Activity Underlying the Maintenance of a Precisely Executed Skilled Behavior.

PubMed

Katlowitz, Kalman A; Picardo, Michel A; Long, Michael A

2018-05-21

A vast array of motor skills can be maintained throughout life. Do these behaviors require stability of individual neuron tuning or can the output of a given circuit remain constant despite fluctuations in single cells? This question is difficult to address due to the variability inherent in most motor actions studied in the laboratory. A notable exception, however, is the courtship song of the adult zebra finch, which is a learned, highly precise motor act mediated by orderly dynamics within premotor neurons of the forebrain. By longitudinally tracking the activity of excitatory projection neurons during singing using two-photon calcium imaging, we find that both the number and the precise timing of song-related spiking events remain nearly identical over the span of several weeks to months. These findings demonstrate that learned, complex behaviors can be stabilized by maintaining precise and invariant tuning at the level of single neurons. Copyright © 2018 Elsevier Inc. All rights reserved.

Nickel-silicide colloid prepared under mild conditions as a versatile Ni precursor for more efficient CO2 reforming of CH4 catalysts.

PubMed

Baudouin, David; Szeto, Kaï Chung; Laurent, Pierre; De Mallmann, Aimery; Fenet, Bernard; Veyre, Laurent; Rodemerck, Uwe; Copéret, Christophe; Thieuleux, Chloé

2012-12-26

Preparing highly active and stable non-noble-metal-based dry reforming catalysts remains a challenge today. In this context, supported nickel nanoparticles with sizes of 1.3 ± 0.2 and 2.1 ± 0.2 nm were synthesized on silica and ceria, respectively, via a two-step colloidal approach. First, 2-nm nickel-silicide colloids were synthesized from Ni(COD)(2) and octylsilane at low temperature; they were subsequently dispersed onto supports prior to reduction under H(2). The resulting catalysts display high activity in dry reforming compared to their analogues prepared using conventional approaches, ceria providing greatly improved catalyst stability.

Applications of stable isotope analysis in mammalian ecology.

PubMed

Walter, W David; Kurle, Carolyn M; Hopkins, John B

2014-01-01

In this editorial, we provide a brief introduction and summarize the 10 research articles included in this Special Issue on Applications of stable isotope analysis in mammalian ecology. The first three articles report correction and discrimination factors that can be used to more accurately estimate the diets of extinct and extant mammals using stable isotope analysis. The remaining seven applied research articles use stable isotope analysis to address a variety of wildlife conservation and management questions from the oceans to the mountains.

Synthesis of adriamycin-coupled polyglutaraldehyde microspheres and evaluation of their cytostatic activity

NASA Technical Reports Server (NTRS)

Tokes, Z. A.; Rogers, K. E.; Rembaum, A.

1982-01-01

Adriamycin was coupled to polyglutaraldehyde microspheres having an average diameter of 4500 A. The coupled microspheres remained stable during incubation with cells. Full cytostatic activity was observed when the coupled adriamycin was tested with murine or human leukemia and murine sarcoma cell lines. A 10-fold increase in sensitivity was obtained with drug-resistant human leukemia cell lines. Repeated use of the coupled microspheres in the cytostatic assays did not decrease their activity, indicating that these complexes can be recycled. The results suggest that coupled adriamycin sufficiently perturbs the plasma membrane to lead to cytostatic activity. It is proposed that this mode of drug delivery provides multiple and repetitious sites for drug-cell interactions. In addition, the drug-polymer complexes may overcome those forms of resistance that are the result of decreased drug binding at the cell surface.

High-level heterologous expression and properties of a novel lipase from Ralstonia sp. M1.

PubMed

Quyen, Dinh Thi; Giang Le, Thi Thu; Nguyen, Thi Thao; Oh, Tae-Kwang; Lee, Jung-Kee

2005-01-01

The mature lipase LipA and its 56aa-truncated chaperone DeltaLipBhis (with 6xhis-tag) from Ralstonia sp. M1 were over-expressed in Escherichia coli BL21 under the control of T7 promoter with a high level of 70 and 12mg protein per gram of wet cells, respectively. The simply purified lipase LipA was effectively refolded by Ni-NTA purified chaperone DeltaLipBhis in molar ratio 1:1 at 4 degrees C for 24 hours in H2O. The in vitro refolded lipase LipA had an optimal activity in the temperature range of 50-55 degrees C and was stable up to 45 degrees C with more than 84% activity retention. The maximal activity was observed at pH 10.75 for hydrolysis of olive oil and found to be stable over alkaline pH range 8.0-10.5 with more than 52% activity retention. The enzyme was found to be highly resistant to many organic solvents especially induced by ethanolamine (remaining activity 137-334%), but inhibited by 1-butanol and acetonitrile (40-86%). Metal ions Cu2+, Sn2+, Mn2+, Mg2+, and Ca2+ stimulated the lipase slightly with increase in activity by up to 22%, whereas Zn2+ significantly inhibited the enzyme with the residual activity of 30-65% and Fe3+ to a lesser degree (activity retention of 77-86%). Tween 80, Tween 60, and Tween 40 induced the activation of the lipase LipA (222-330%) and 0.2-1% (w/v) of Triton X-100, X-45, and SDS increased the lipase activity by up to 52%. However, 5% (w/v) of Triton X-100, X-45, and SDS inhibited strongly the activity by 31-89%. The inhibitors including DEPC, EDTA, PMSF, and 2-mercaptoethanol (0.1-10mM) inhibited moderately the lipase with remaining activity of 57-105%. The lipase LipA hydrolyzed a wide range of triglycerides, but preferentially short length acyl chains (C4 and C6). In contrast to the triglycerides, medium length acyl chains (C8 and C14) of p-nitrophenyl (p-NP) esters were preferential substrates of this lipase. The enzyme preferentially catalyzed the hydrolysis of cottonseed oil (317%), cornoil (227%), palm oil (222%), and wheatgerm oil (210%) in comparison to olive oil (100%).

Neuromodulation to the Rescue: Compensation of Temperature-Induced Breakdown of Rhythmic Motor Patterns via Extrinsic Neuromodulatory Input

PubMed Central

Städele, Carola; Heigele, Stefanie; Stein, Wolfgang

2015-01-01

Stable rhythmic neural activity depends on the well-coordinated interplay of synaptic and cell-intrinsic conductances. Since all biophysical processes are temperature dependent, this interplay is challenged during temperature fluctuations. How the nervous system remains functional during temperature perturbations remains mostly unknown. We present a hitherto unknown mechanism of how temperature-induced changes in neural networks are compensated by changing their neuromodulatory state: activation of neuromodulatory pathways establishes a dynamic coregulation of synaptic and intrinsic conductances with opposing effects on neuronal activity when temperature changes, hence rescuing neuronal activity. Using the well-studied gastric mill pattern generator of the crab, we show that modest temperature increase can abolish rhythmic activity in isolated neural circuits due to increased leak currents in rhythm-generating neurons. Dynamic clamp-mediated addition of leak currents was sufficient to stop neuronal oscillations at low temperatures, and subtraction of additional leak currents at elevated temperatures was sufficient to rescue the rhythm. Despite the apparent sensitivity of the isolated nervous system to temperature fluctuations, the rhythm could be stabilized by activating extrinsic neuromodulatory inputs from descending projection neurons, a strategy that we indeed found to be implemented in intact animals. In the isolated nervous system, temperature compensation was achieved by stronger extrinsic neuromodulatory input from projection neurons or by augmenting projection neuron influence via bath application of the peptide cotransmitter Cancer borealis tachykinin-related peptide Ia (CabTRP Ia). CabTRP Ia activates the modulator-induced current IMI (a nonlinear voltage-gated inward current) that effectively acted as a negative leak current and counterbalanced the temperature-induced leak to rescue neuronal oscillations. Computational modelling revealed the ability of IMI to reduce detrimental leak-current influences on neuronal networks over a broad conductance range and indicated that leak and IMI are closely coregulated in the biological system to enable stable motor patterns. In conclusion, these results show that temperature compensation does not need to be implemented within the network itself but can be conditionally provided by extrinsic neuromodulatory input that counterbalances temperature-induced modifications of circuit-intrinsic properties. PMID:26417944

Effects of transgenic Bt rice on the active rhizospheric methanogenic archaeal community as revealed by DNA-based stable isotope probing.

PubMed

Han, Cheng; Liu, Biao; Zhong, Wenhui

2018-05-30

This study aimed to investigate the influence of planting Cry1Ab/Cry1Ac gene expressing rice (Bt rice) on rhizospheric active methanogenic archaeal communities. The non-transgenic parental line was used as the control (Ck rice). DNA-based stable isotope probing (DNA-SIP) technology traced the rhizospheric active methanogens at the tillering stage. The results revealed significantly lower CH 4 emission flux from Bt soil than that from Ck soil during the whole growth period. The active methanogenic community composition remained stable. The RC-I lineage (77.9-79.8%) and Methanosaetaceae (13.9-15.1%) were the predominant active methanogens in Bt and Ck rice rhizospheres. However, the abundance of functionally active methanogens in the Bt rice rhizosphere was significantly reduced. Lower levels of root exudates (that included carbohydrate and organic acids) from Bt rice were also detected at the tillering stage. This study found that the genetic modification of rice reduced the potential methanogenic substrates came from plant-derived root exudates, which represented an important factor in reducing CH 4 generation and active methanogenic archaeal abundance in Bt rhizosphere soil. The effect of genetically modified (GM) insect-resistant crops on soil microorganisms has become an issue of public concern, especially the indirect effect of plant metabolisms caused by the insertion of foreign genes. Methanogenesis, which is regarded as a critical ecological process in paddy soil, is influenced by plant root exudates; these are mainly derived from photosynthesis. The variations in root exudates across the Bt and Ck rice suggested the indirect influence of foreign gene insertion. DNA-SIP successfully traced the active methanogenic archaeal populations assimilating 13 C-labeled photosynthetic carbon and found a strong influence of planting Bt rice on active methanogens. As a consequence, we proposed that analysis of functionally active microorganisms is more suitable for monitoring and predicting the environmental influence of GM plants. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Psychosocial work conditions, social participation and social capital: a causal pathway investigated in a longitudinal study.

PubMed

Lindström, Martin

2006-01-01

Social capital is often claimed to be promoted by stable social structures such as low migration rates between neighbourhoods and social networks that remain stable over time. However, stable social structures may also inhibit the formation of social capital in the form of social networks and social participation. One example is psychosocial conditions at work, which may be determined by characteristics such as demand and control in the work situation. The study examines the active workforce subpopulation within the Swedish Malmö Shoulder Neck Study. A total of 7836 individuals aged 45-69 years, were interviewed at baseline between 1992 and 1994, and at a 1-year follow-up. Four groups of baseline psychosocial work conditions categories defined by the Karasek-Theorell model (jobstrain, passive, active, relaxed) were analysed according to 13 different social participation items during the past year reported at the 1-year follow-up. Odds ratios and 95% confidence intervals with the jobstrain group as a reference were estimated. A multivariate logistic regression model was used to assess differences in different aspects of social participation between the four psychosocial work conditions groups. The results show that the respondents within the active category in particular but also the relaxed category, have significantly higher participation in many of the 13 social participation items, even after multivariate adjustments. The results strongly suggest that psychosocial work conditions may be an important determinant of social capital measured as social participation, a finding of immediate public health relevance because of the well known positive association between social participation and health-related behaviours.

Activity of Culicoides spp. (Diptera: Ceratopogonidae) inside and outside of livestock stables in late winter and spring.

PubMed

Kameke, Daniela; Kampen, Helge; Walther, Doreen

2017-03-01

Culicoides Latreille, 1809 midge species are the putative vectors of Bluetongue virus (BTV) and Schmallenberg virus (SBV) in Europe. To gain a better understanding of the epidemiology of the diseases, basic knowledge about the overwintering of the vectors is needed. Therefore, we investigated culicoid activity in relation to air temperature at livestock stables during late winter and spring season. Ceratopogonids were captured weekly indoors and outdoors on three cattle farms, three horse farms and one sheep farm in the federal state of Brandenburg, Germany between January and May, 2015 by BG-Sentinel UV-light suction traps. First seasonal activity was measured inside a sheep barn and cattle stables in mid-March, suggesting the existence of a preceding vector-free period. The first species at all trapping sites were members of the Obsoletus Complex followed by Culicoides punctatus (Meigen), 1804 and Culicoides pulicaris (Linnaeus), 1758 simultaneously. In total, 160 collections were made, including 3465 Culicoides specimens with 2790 (80.6%) of them being members of the Obsoletus Complex. The remaining 675 individuals belonged to six other culicoid species. 59.8% of all Culicoides were collected indoors, and almost five times as many midges were sampled on cattle farms as on horse farms. Cattle farms harboured seven species while only two species were found on the horse and the sheep farms, respectively. Temperatures, husbandry practises and the presence/quality of potential breeding sites might be responsible for the difference in species and numbers of caught specimens between livestock holdings.

[The kinological identification of individual scents in the traces of the vital activities of 4 vertebrate species].

PubMed

Sokolov, V E; Sulimov, K T; Krutova, V I

1990-01-01

One can successfully identify individual odors of almost any terrestrial vertebrates using laboratory dogs. The excretions can be collected on adsorbent paper and conserved for subsequent identification. It has been experimentally shown that the odor of house mice remains stable during the whole life span and that the stabilization of dog-identifiable odors finishes in young mice at 14 day. The method tested will allow to create individual banks of animal odors, e.g. for identification of rare species.

Health of Women after Wartime Deployments: Correlates of Risk for Selected Medical Conditions among Females after Initial and Repeat Deployments to Afghanistan and Iraq, Active Component, U.S. Armed Forces

DTIC Science & Technology

2012-07-01

719.xx Peripheral enthesopathies, allied syndromes 726.xx Reproductive system disorders Disorders of menstruation /other abnormal bleeding 626.xx...range, 2.0%-2.8%), while the percentages diagnosed with “disorders of menstruation ” remained stable (range, 7.6%-8.0%), with increasing number...between the condi- tions. For example, in multivariate analyses, MSMR Vol. 19 No. 7 July 2012Page 6 Reproductive system disorders Menstruation

Injectable nanocarriers for biodetoxification

NASA Astrophysics Data System (ADS)

Leroux, Jean-Christophe

2007-11-01

Hospitals routinely treat patients suffering from overdoses of drugs or other toxic chemicals as a result of illicit drug consumption, suicide attempts or accidental exposures. However, for many life-threatening situations, specific antidotes are not available and treatment is largely based on emptying the stomach, administering activated charcoal or other general measures of intoxication support. A promising strategy for managing such overdoses is to inject nanocarriers that can extract toxic agents from intoxicated tissues. To be effective, the nanocarriers must remain in the blood long enough to sequester the toxic components and/or their metabolites, and the toxin bound complex must also remain stable until it is removed from the bloodstream. Here, we discuss the principles that govern the use of injectable nanocarriers in biodetoxification and review the pharmacological performance of a number of different approaches.

Chameleon-like elastomers with molecularly encoded strain-adaptive stiffening and coloration

NASA Astrophysics Data System (ADS)

Vatankhah-Varnosfaderani, Mohammad; Keith, Andrew N.; Cong, Yidan; Liang, Heyi; Rosenthal, Martin; Sztucki, Michael; Clair, Charles; Magonov, Sergei; Ivanov, Dimitri A.; Dobrynin, Andrey V.; Sheiko, Sergei S.

2018-03-01

Active camouflage is widely recognized as a soft-tissue feature, and yet the ability to integrate adaptive coloration and tissuelike mechanical properties into synthetic materials remains elusive. We provide a solution to this problem by uniting these functions in moldable elastomers through the self-assembly of linear-bottlebrush-linear triblock copolymers. Microphase separation of the architecturally distinct blocks results in physically cross-linked networks that display vibrant color, extreme softness, and intense strain stiffening on par with that of skin tissue. Each of these functional properties is regulated by the structure of one macromolecule, without the need for chemical cross-linking or additives. These materials remain stable under conditions characteristic of internal bodily environments and under ambient conditions, neither swelling in bodily fluids nor drying when exposed to air.

Interactions of oxygen and ethylene with submonolayer Ag films supported on Ni(111).

PubMed

Rettew, Robert E; Meyer, Axel; Senanayake, Sanjaya D; Chen, Tsung-Liang; Petersburg, Cole; Ingo Flege, J; Falta, Jens; Alamgir, Faisal M

2011-06-21

We investigate the oxidation of, and the reaction of ethylene with, Ni(111) with and without sub-monolayer Ag adlayers as a function of temperature. The addition of Ag to Ni(111) is shown to enhance the activity towards the ethylene epoxidation reaction, and increase the temperature at which ethylene oxide is stable on the surface. We present a systematic study of the formation of chemisorbed oxygen on the Ag-Ni(111) surfaces and correlate the presence and absence of O(1-) and O(2-) surface species with the reactivity towards ethylene. By characterizing the samples with low-energy electron microscopy (LEEM) in combination with X-ray photoelectron spectroscopy (XPS), we have identified specific growth of silver on step-edge sites and successfully increased the temperature at which the produced ethylene oxide remains stable, a trait which is desirable for catalysis.

Boron doped graphene wrapped silver nanowires as an efficient electrocatalyst for molecular oxygen reduction

PubMed Central

Nair, Anju K.; Thazhe veettil, Vineesh; Kalarikkal, Nandakumar; Thomas, Sabu; Kala, M. S.; Sahajwalla, Veena; Joshi, Rakesh K.; Alwarappan, Subbiah

2016-01-01

Metal nanowires exhibit unusually high catalytic activity towards oxygen reduction reaction (ORR) due to their inherent electronic structures. However, controllable synthesis of stable nanowires still remains as a daunting challenge. Herein, we report the in situ synthesis of silver nanowires (AgNWs) over boron doped graphene sheets (BG) and demonstrated its efficient electrocatalytic activity towards ORR for the first time. The electrocatalytic ORR efficacy of BG-AgNW is studied using various voltammetric techniques. The BG wrapped AgNWs shows excellent ORR activity, with very high onset potential and current density and it followed four electron transfer mechanism with high methanol tolerance and stability towards ORR. The results are comparable to the commercially available 20% Pt/C in terms of performance. PMID:27941954

Persistently active neurons in human medial frontal and medial temporal lobe support working memory

PubMed Central

Kamiński, J; Sullivan, S; Chung, JM; Ross, IB; Mamelak, AN; Rutishauser, U

2017-01-01

Persistent neural activity is a putative mechanism for the maintenance of working memories. Persistent activity relies on the activity of a distributed network of areas, but the differential contribution of each area remains unclear. We recorded single neurons in the human medial frontal cortex and the medial temporal lobe while subjects held up to three items in memory. We found persistently active neurons in both areas. Persistent activity of hippocampal and amygdala neurons was stimulus-specific, formed stable attractors, and was predictive of memory content. Medial frontal cortex persistent activity, on the other hand, was modulated by memory load and task set but was not stimulus-specific. Trial-by-trial variability in persistent activity in both areas was related to memory strength, because it predicted the speed and accuracy by which stimuli were remembered. This work reveals, in humans, direct evidence for a distributed network of persistently active neurons supporting working memory maintenance. PMID:28218914

Seasonal variations in photosystem I compared with photosystem II of three alpine evergreen broad-leaf tree species.

PubMed

Huang, Wei; Yang, Ying-Jie; Hu, Hong; Zhang, Shi-Bao

2016-12-01

Low temperature associated with high light can induce photoinhibition of photosystem I (PSI) and photosystem II (PSII). However, the photosynthetic electron flow and specific photoprotective responses in alpine evergreen broad-leaf plants in winter is unclear. We analyzed seasonal changes in PSI and PSII activities, and energy quenching in PSI and PSII in three alpine broad-leaf tree species, Quercus guyavifolia (Fagaceae), Rhododendron decorum (Ericaceae), Euonymus tingens (Celastraceae). In winter, PSII activity remained stable in Q. guyavifolia but decreased significantly in R. decorum and E. tingens. Q. guyavifolia showed much higher capacities of cyclic electron flow (CEF), water-water cycle (WWC), non-photochemical quenching (NPQ) than R. decorum and E. tingens in winter. These results indicated that in alpine evergreen broad-leaf tree species the PSII activity in winter was closely related to these photoprotective mechanisms. Interestingly, unlike PSII, PSI activity was maintained stable in winter in the three species. Meanwhile, photosynthetic electron flow from PSII to PSI (ETRII) was much higher in Q. guyavifolia, suggesting that the mechanisms protecting PSI activity against photoinhibition in winter differed among the three species. A high level of CEF contributed the stability of PSI activity in Q. guyavifolia. By comparison, R. decorum and E. tingens prevented PSI photoinhibition through depression of electron transport to PSI. Taking together, CEF, WWC and NPQ played important roles in coping with excess light energy in winter for alpine evergreen broad-leaf tree species. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of physical activity training in patients with Alzheimer's dementia: results of a pilot RCT study.

PubMed

Holthoff, Vjera A; Marschner, Kira; Scharf, Maria; Steding, Julius; Meyer, Shirin; Koch, Rainer; Donix, Markus

2015-01-01

There is evidence that physical activity (PA) is of cognitive benefit to the ageing brain, but little is known on the effect in patients with Alzheimer's disease (AD). The present pilot study assessed the effect of a home-based PA training on clinical symptoms, functional abilities, and caregiver burden after 12 and 24 weeks. In an RCT thirty patients (aged 72.4±4.3 years) with AD (MMSE: 20.6±6.5 points) and their family caregivers were allocated to a home-based 12-week PA intervention program or the usual care group. The program changed between passive, motor-assisted or active resistive leg training and changes in direction on a movement trainer in order to combine physical and cognitive stimuli. Analysis of activities of daily living in the patients (ADCS ADL total score) revealed a significant group × time interaction effect (95% CI of the difference between both groups at T2: 5.01-10.51). The control group experienced decreases in ADL performance at week 12 and 24 whereas patients in the intervention group remained stable. Analyses of executive function and language ability revealed considerable effects for semantic word fluency with a group × time interaction (95% CI of the difference between both groups at T2: 0.18-4.02). Patients in the intervention group improved during the intervention and returned to initial performance at week 12 whereas the controls revealed continuous worsening. Analyses of reaction time, hand-eye quickness and attention revealed improvement only in the intervention group. Caregiver burden remained stable in the intervention group but worsened in the control group. This study suggests that PA in a home-based setting might be an effective and intrinsically attractive way to promote PA training in AD and modulate caregiver burden. The results demonstrate transfer benefits to ADL, cognitive and physical skill in patients with AD. ClinicalTrials.gov NCT02196545.

Identifying low pH active and lactate-utilizing taxa within oral microbiome communities from healthy children using stable isotope probing techniques.

PubMed

McLean, Jeffrey S; Fansler, Sarah J; Majors, Paul D; McAteer, Kathleen; Allen, Lisa Z; Shirtliff, Mark E; Lux, Renate; Shi, Wenyuan

2012-01-01

Many human microbial infectious diseases including dental caries are polymicrobial in nature. How these complex multi-species communities evolve from a healthy to a diseased state is not well understood. Although many health- or disease-associated oral bacteria have been characterized in vitro, their physiology within the complex oral microbiome is difficult to determine with current approaches. In addition, about half of these species remain uncultivated to date with little known besides their 16S rRNA sequence. Lacking culture-based physiological analyses, the functional roles of uncultivated species will remain enigmatic despite their apparent disease correlation. To start addressing these knowledge gaps, we applied a combination of Magnetic Resonance Spectroscopy (MRS) with RNA and DNA based Stable Isotope Probing (SIP) to oral plaque communities from healthy children for in vitro temporal monitoring of metabolites and identification of metabolically active and inactive bacterial species. Supragingival plaque samples from caries-free children incubated with (13)C-substrates under imposed healthy (buffered, pH 7) and diseased states (pH 5.5 and pH 4.5) produced lactate as the dominant organic acid from glucose metabolism. Rapid lactate utilization upon glucose depletion was observed under pH 7 conditions. SIP analyses revealed a number of genera containing cultured and uncultivated taxa with metabolic capabilities at pH 5.5. The diversity of active species decreased significantly at pH 4.5 and was dominated by Lactobacillus and Propionibacterium species, both of which have been previously found within carious lesions from children. Our approach allowed for identification of species that metabolize carbohydrates under different pH conditions and supports the importance of Lactobacilli and Propionibacterium in the development of childhood caries. Identification of species within healthy subjects that are active at low pH can lead to a better understanding of oral caries onset and generate appropriate targets for preventative measures in the early stages.

Transient impairment of olfactory threshold in acute multiple sclerosis relapse.

PubMed

Bsteh, Gabriel; Hegen, Harald; Ladstätter, Felix; Berek, Klaus; Amprosi, Matthias; Wurth, Sebastian; Auer, Michael; Di Pauli, Franziska; Deisenhammer, Florian; Lutterotti, Andreas; Berger, Thomas

2018-05-18

Impairment of olfactory threshold is a feature of early and active relapsing remitting multiple sclerosis (RRMS). It predicts inflammatory disease activity and was reported to be transient. However, the timing of onset and resolve of olfactory threshold impairment remains unclear. To prospectively assess the development of olfactory threshold in acute MS relapse over time in comparison to stable MS patients. In a prospective observational design, we measured olfactory threshold by performing the Sniffin' Sticks test (minimum score 0, maximum score 16 reflecting optimal olfactory function) at baseline and after 4, 12 and 24 weeks. We included 30 RRMS patients with acute MS relapse and 30 clinically stable RRMS patients (defined as no relapse within the last 12 months) as a control group. Olfactory threshold was impaired in patients with acute MS relapse at baseline (median difference = -3.5; inter-quartile range [IQR] -4.5- - 2.5; p < 0.001), week 4 (-2.5; IQR -3.0 - -2.0; p < 0.001), week 12 (-1.5; IQR -2.0 - -0.5; p = 0.002) and week 24 (-0.5; IQR -1.0 - 0.0; p = 0.159) compared to stable MS patients. Of note, in relapsing patients in whom disease-modifying treatment was initiated or escalated after relapse, threshold did not differ anymore from stable patients at week 12 (-0.5; IQR -1.0 - 0.5; p = 0.247) and week 24 (0.0; IQR -1.0 - 1.0; p = 0.753). Olfactory threshold impairment seems to be a transient bystander feature of MS relapse. It may be correlated to the level of inflammation within the CNS and might be a useful biomarker in this regard. Copyright © 2018 Elsevier B.V. All rights reserved.

Ultrathin MoS2-coated Ag@Si nanosphere arrays as an efficient and stable photocathode for solar-driven hydrogen production

NASA Astrophysics Data System (ADS)

Zhou, Qingwei; Su, Shaoqiang; Hu, Die; Lin, Lin; Yan, Zhibo; Gao, Xingsen; Zhang, Zhang; Liu, Jun-Ming

2018-03-01

Solar-driven photoelectrochemical (PEC) water splitting has attracted a great deal of attention recently. Silicon (Si) is an ideal light absorber for solar energy conversion. However, the poor stability and inefficient surface catalysis of Si photocathodes for the hydrogen evolution reaction (HER) have remained key challenges. Alternatively, MoS2 has been reported to exhibit excellent catalysis performance if sufficient active sites for the HER are available. Here, ultrathin MoS2 nanoflakes are directly synthesized to coat arrays of Ag-core Si-shell nanospheres (Ag@Si NSs) by using chemical vapor deposition. Due to the high surface area ratio and large curvature of these NSs, the as-grown MoS2 nanoflakes can accommodate more active sites. In addition, the high-quality coating of MoS2 nanoflakes on the Ag@Si NSs protects the photocathode from damage during the PEC reaction. An photocurrent density of 33.3 mA cm-2 at a voltage of -0.4 V is obtained versus the reversible hydrogen electrode. The as-prepared nanostructure as a hydrogen photocathode is evidenced to have high stability over 12 h PEC performance. This work opens up opportunities for composite photocathodes with high activity and stability using cheap and stable co-catalysts.

Characterization of a novel high-pH-tolerant laccase-like multicopper oxidase and its sequence diversity in Thioalkalivibrio sp.

PubMed

Ausec, Luka; Črnigoj, Miha; Šnajder, Marko; Ulrih, Nataša Poklar; Mandic-Mulec, Ines

2015-12-01

Laccases are oxidoreductases mostly studied in fungi, while bacterial laccases remain poorly studied despite their high genetic diversity and potential for biotechnological application. Our previous bioinformatic analysis identified alkaliphilic bacterial strains Thioalkalivibrio sp. as potential sources of robust bacterial laccases that would be stable at high pH. In the present work, a gene for a laccase-like enzyme from Thioalkalivibrio sp. ALRh was cloned and expressed as a 6× His-tagged protein in Escherichia coli. The purified enzyme was a pH-tolerant laccase stable in the pH range between 2.1 and 9.9 at 20 °C as shown by intrinsic fluorescence emission spectrometry. It had optimal activities at pH 5.0 and pH 9.5 with the laccase substrates 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,6-dimethoxyphenol, respectively. In addition, it could oxidize several other monophenolic compounds and potassium hexacyanoferrate(II) but not tyrosine. It showed highest activity at 50 °C, making it suitable for prolonged incubations at this temperature. The present study shows that Thioalkalivibrio sp. encodes an active, alkaliphilic, and thermo-tolerant laccase and contributes to our understanding of the versatility of bacterial laccase-like multicopper oxidases in general.

Ultrathin MoS2-coated Ag@Si nanosphere arrays as an efficient and stable photocathode for solar-driven hydrogen production.

PubMed

Zhou, Qingwei; Su, Shaoqiang; Hu, Die; Lin, Lin; Yan, Zhibo; Gao, Xingsen; Zhang, Zhang; Liu, Jun-Ming

2018-01-30

Solar-driven photoelectrochemical (PEC) water splitting has attracted a great deal of attention recently. Silicon (Si) is an ideal light absorber for solar energy conversion. However, the poor stability and inefficient surface catalysis of Si photocathodes for the hydrogen evolution reaction (HER) have remained key challenges. Alternatively, MoS 2 has been reported to exhibit excellent catalysis performance if sufficient active sites for the HER are available. Here, ultrathin MoS 2 nanoflakes are directly synthesized to coat arrays of Ag-core Si-shell nanospheres (Ag@Si NSs) by using chemical vapor deposition. Due to the high surface area ratio and large curvature of these NSs, the as-grown MoS 2 nanoflakes can accommodate more active sites. In addition, the high-quality coating of MoS 2 nanoflakes on the Ag@Si NSs protects the photocathode from damage during the PEC reaction. An photocurrent density of 33.3 mA cm -2 at a voltage of -0.4 V is obtained versus the reversible hydrogen electrode. The as-prepared nanostructure as a hydrogen photocathode is evidenced to have high stability over 12 h PEC performance. This work opens up opportunities for composite photocathodes with high activity and stability using cheap and stable co-catalysts.

Pt-Richcore/Sn-Richsubsurface/Ptskin Nanocubes As Highly Active and Stable Electrocatalysts for the Ethanol Oxidation Reaction.

PubMed

Rizo, Rubén; Arán-Ais, Rosa M; Padgett, Elliot; Muller, David A; Lázaro, Ma Jesús; Solla-Gullón, José; Feliu, Juan M; Pastor, Elena; Abruña, Héctor D

2018-03-14

Direct ethanol fuel cells are one of the most promising electrochemical energy conversion devices for portable, mobile and stationary power applications. However, more efficient and stable and less expensive electrocatalysts are still required. Interestingly, the electrochemical performance of the electrocatalysts toward the ethanol oxidation reaction can be remarkably enhanced by exploiting the benefits of structural and compositional sensitivity and control. Here, we describe the synthesis, characterization, and electrochemical behavior of cubic Pt-Sn nanoparticles. The electrochemical activity of the cubic Pt-Sn nanoparticles was found to be about three times higher than that obtained with unshaped Pt-Sn nanoparticles and six times higher than that of Pt nanocubes. In addition, stability tests indicated the electrocatalyst preserves its morphology and remains well-dispersed on the carbon support after 5000 potential cycles, while a cubic (pure) Pt catalyst exhibited severe agglomeration of the nanoparticles after a similar stability testing protocol. A detailed analysis of the elemental distribution in the nanoparticles by STEM-EELS indicated that Sn dissolves from the outer part of the shell after potential cycling, forming a ∼0.5 nm Pt skin. This particular atomic composition profile having a Pt-rich core, a Sn-rich subsurface layer, and a Pt-skin surface structure is responsible for the high activity and stability.

Efficient Parvovirus Replication Requires CRL4Cdt2-Targeted Depletion of p21 to Prevent Its Inhibitory Interaction with PCNA

PubMed Central

Pintel, David J.

2014-01-01

Infection by the autonomous parvovirus minute virus of mice (MVM) induces a vigorous DNA damage response in host cells which it utilizes for its efficient replication. Although p53 remains activated, p21 protein levels remain low throughout the course of infection. We show here that efficient MVM replication required the targeting for degradation of p21 during this time by the CRL4Cdt2 E3-ubiquitin ligase which became re-localized to MVM replication centers. PCNA provides a molecular platform for substrate recognition by the CRL4Cdt2 E3-ubiquitin ligase and p21 targeting during MVM infection required its interaction both with Cdt2 and PCNA. PCNA is also an important co-factor for MVM replication which can be antagonized by p21 in vitro. Expression of a stable p21 mutant that retained interaction with PCNA inhibited MVM replication, while a stable p21 mutant which lacked this interaction did not. Thus, while interaction with PCNA was important for targeting p21 to the CRL4Cdt2 ligase re-localized to MVM replication centers, efficient viral replication required subsequent depletion of p21 to abrogate its inhibition of PCNA. PMID:24699724

Efficient parvovirus replication requires CRL4Cdt2-targeted depletion of p21 to prevent its inhibitory interaction with PCNA.

PubMed

Adeyemi, Richard O; Fuller, Matthew S; Pintel, David J

2014-04-01

Infection by the autonomous parvovirus minute virus of mice (MVM) induces a vigorous DNA damage response in host cells which it utilizes for its efficient replication. Although p53 remains activated, p21 protein levels remain low throughout the course of infection. We show here that efficient MVM replication required the targeting for degradation of p21 during this time by the CRL4Cdt2 E3-ubiquitin ligase which became re-localized to MVM replication centers. PCNA provides a molecular platform for substrate recognition by the CRL4Cdt2 E3-ubiquitin ligase and p21 targeting during MVM infection required its interaction both with Cdt2 and PCNA. PCNA is also an important co-factor for MVM replication which can be antagonized by p21 in vitro. Expression of a stable p21 mutant that retained interaction with PCNA inhibited MVM replication, while a stable p21 mutant which lacked this interaction did not. Thus, while interaction with PCNA was important for targeting p21 to the CRL4Cdt2 ligase re-localized to MVM replication centers, efficient viral replication required subsequent depletion of p21 to abrogate its inhibition of PCNA.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koepf, Matthieu; Bergkamp, Jesse J.; Teillout, Anne-Lucie

The association of different metals in stable, well-defined molecular assemblies remains a great challenge of supramolecular chemistry. In such constructs, the emergence of synergism, or cooperative effects between the different metal centers is particularly intriguing. These effects can lead to uncommon reactivity or remarkable physico-chemical properties that are not otherwise achievable. For example, the association of alkaline or alkaline-earth cations and transition metals is pivotal for the activity of several biomolecules and human-made catalysts that carry out fundamental redox transformations (water oxidation, nitrogen reduction, water–gas shift reaction, etc.). In many cases the precise nature of the interactions between the alkaline-earthmore » cations and the redox-active transition metals remains elusive due to the difficulty of building stable molecular heterometallic assemblies that associate transition metals and alkaline or alkaline-earth cations in a controlled way. In this work we present the rational design of porphyrin-based ligands possessing a second binding site for alkaline-earth cations above the porphyrin macrocycle primary complexation site. We demonstrate that by using a combination of crown ether and carboxylic acid substituents suitably positioned on the periphery of the porphyrin, bitopic ligands can be obtained. The binding of calcium, a typical alkaline-earth cation, by the newly prepared ligands has been studied in detail and we show that a moderately large binding constant can be achieved in protic media using ligands that possess some degree of structural flexibility. The formation of Zn–Ca assemblies discussed in this work is viewed as a stepping stone towards the assembly of well defined molecular transition metal-alkaline earth bimetallic centers using a versatile organic scaffold.« less

Effects of polysaccharopeptide from Trametes versicolor and amoxicillin on the gut microbiome of healthy volunteers: a randomized clinical trial.

PubMed

Pallav, Kumar; Dowd, Scot E; Villafuerte, Javier; Yang, Xiaotong; Kabbani, Toufic; Hansen, Joshua; Dennis, Melinda; Leffler, Daniel A; Newburg, David S; Kelly, Ciarán P

2014-07-01

Interactions between the microbial flora of the intestine and the human host play a critical role inmaintaining intestinal health and in the pathophysiology of a wide variety of disorders such as antibiotic associated diarrhea, Clostridium difficile infection, and inflammatory bowel disease. Prebiotics can confer health benefits by beneficial effects on the intestinal microbiome, whereas antibiotics can disrupt the microbiome leading to diarrhea andother side effects. To compare the effects of the prebiotic, polysaccharopeptide from Trametes versicolor, to those of the antibiotic,amoxicillin, on the human gut microbiome Twenty-four healthy volunteers were randomized to receive PSP, amoxicillin, or no treatment (control).Stool specimens were analyzed using bTEFAP microbial ecology methods on seven occasions over 8 weeks from each participant in the active treatment groups and on three occasions for the controls. Twenty-two of 24 participants completed the protocol. PSP led to clear and consistent microbiome changes consistent with its activity as a prebiotic. Despite the diversity of the human microbiome we noted strong microbiome clustering among subjects. Baseline microbiomes tended to remain stable and to overshadow the treatment effects.Amoxicillin treatment caused substantial microbiome changes most notably an increase in Escherichia/Shigella. Antibiotic associated changes persisted to the end of the study, 42 days after antibiotic therapy ended. The microbiomes of healthy individuals show substantial diversity but remain stable over time.The antibiotic amoxicillin alters the microbiome and recovery from this disruption can take several weeks. PSP from T. versicolor acts as a prebiotic to modulate human intestinal microbiome composition.

Inhibition of AMPK catabolic action by GSK3

PubMed Central

Suzuki, Tsukasa; Bridges, Dave; Nakada, Daisuke; Skiniotis, Georgios; Morrison, Sean J.; Lin, Jiandie; Saltiel, Alan R.; Inoki, Ken

2013-01-01

SUMMARY AMP-activated protein kinase (AMPK) regulates cellular energy homeostasis by inhibiting anabolic and activating catabolic processes. While AMPK activation has been extensively studied, mechanisms that inhibit AMPK remain elusive. Here we report that glycogen synthase kinase 3 (GSK3) inhibits AMPK function. GSK3 forms a stable complex with AMPK through interactions with the AMPK β regulatory subunit and phosphorylates the AMPK α catalytic subunit. This phosphorylation enhances the accessibility of the activation loop of the α subunit to phosphatases, thereby inhibiting AMPK kinase activity. Surprisingly, PI3K-Akt signaling, which is a major anabolic signaling and normally inhibits GSK3 activity, promotes GSK3 phosphorylation and inhibition of AMPK, thus revealing how AMPK senses anabolic environments in addition to cellular energy levels. Consistently, disrupting GSK3 function within the AMPK complex sustains higher AMPK activity and cellular catabolic processes even under anabolic conditions, indicating that GSK3 acts as a critical sensor for anabolic signaling to regulate AMPK. PMID:23623684

A single-centre 10-year experience with Candida bloodstream infections

PubMed Central

Labbé, Annie-Claude; Pépin, Jacques; Patiño, Carlos; Castonguay, Stéphanie; Restieri, Christiane; Laverdiere, Michel

2009-01-01

OBJECTIVE: To describe the clinical and microbiological features associated with Candida bloodstream infections observed at Hôpital Maisonneuve-Rosemont (Montreal, Quebec) between August 1996 and July 2006. METHODS: Episodes were retrieved from the microbiology laboratory. Different patient episodes and different isolate episodes in the same patient were selected. Antifungal susceptibility was determined by the Clinical and Laboratory Standards Institute’s (USA) M27A2 method. RESULTS: A total of 190 different episodes of candidemia in 185 patients were identified. Eleven (6%) episodes occurred in outpatients. Candida albicans was identified in the majority of episodes (57%). Its frequency remained stable over the years. The proportion of Candida krusei candidemia episodes increased between 2003 and 2006, but this was not statistically significant. A central venous indwelling catheter or a peripherally inserted central catheter line was present in the majority of patients (167 [88%]). Of the indwelling catheters removed at the time of diagnosis, 39% were positive for Candida species on culture. Overall, voriconazole was the most active agent (the minimum inhibitory concentration required to inhibit the growth of 90% of organisms was 0.5 mg/L). Resistance to fluconazole was observed in 26 (14%) isolates (C albicans, 4%; versus non-albicans Candida species, 27%; P<0.001). Being on the hematology-oncology unit at the time of diagnosis (adjusted OR 7.8; 95% CI 2.3 to 27.1; P=0.001) and having received fluconazole or itraconazole within the past three months (adjusted OR 8.3; 95% CI 2.8 to 24.4; P<0.001) were significantly associated with resistance to fluconazole in multivariate analysis. CONCLUSIONS: At Hôpital Maisonneuve-Rosemont, the frequency and species distribution of blood isolates of Candida remained stable over the past decade. In vitro resistance of C albicans to fluconazole and itraconazole remained minimal; resistance of non-albicans Candida species to fluconazole did not increase significantly. The new antifungal agents all had high in vitro activity against the bloodstream Candida isolates. PMID:20514159

Technetium-fibrinogen lung scanning in canine lung contusion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geller, E.; Khaw, B.A.; Strauss, H.W.

1984-07-01

To detect experimentally induced acute lung contusion in anesthetized dogs, serial radionuclide images of the lung were recorded following intravenous infusion of 99mTc-labelled human fibrinogen (Tc-HF). The accumulation of Tc-HF in canine lungs was serially quantitated for up to 20 hours after lung contusion. A contusion (number1) was produced in one lung, Tc-HF was injected IV after 15 minutes, and 75 minutes later a contralateral lung contusion (number2) was produced in a series of 14 dogs. At autopsy the excised lungs were scanned, sectioned, and counted for radioactivity. Radiolabelled fibrinogen accumulated within 2-4 minutes of contusion number2 and remained stablemore » over the next 20 hours in 14 dogs; contusion number1 was barely visible in four dogs. Lung Tc-HF activity in the central region of contusion number2 remained sixfold higher than in normal lung tissue. These data suggest that following lung contusion, fibrinogen deposition occurs rapidly and remains stable over a 20-hour interval of observation.« less

A competent catalytic active site is necessary for substrate induced dimer assembly in triosephosphate isomerase.

PubMed

Jimenez-Sandoval, Pedro; Vique-Sanchez, Jose Luis; Hidalgo, Marisol López; Velazquez-Juarez, Gilberto; Diaz-Quezada, Corina; Arroyo-Navarro, Luis Fernando; Moran, Gabriela Montero; Fattori, Juliana; Jessica Diaz-Salazar, A; Rudiño-Pinera, Enrique; Sotelo-Mundo, Rogerio; Figueira, Ana Carolina Migliorini; Lara-Gonzalez, Samuel; Benítez-Cardoza, Claudia G; Brieba, Luis G

2017-11-01

The protozoan parasite Trichomonas vaginalis contains two nearly identical triosephosphate isomerases (TvTIMs) that dissociate into stable monomers and dimerize upon substrate binding. Herein, we compare the role of the "ball and socket" and loop 3 interactions in substrate assisted dimer assembly in both TvTIMs. We found that point mutants at the "ball" are only 39 and 29-fold less catalytically active than their corresponding wild-type counterparts, whereas Δloop 3 deletions are 1502 and 9400-fold less active. Point and deletion mutants dissociate into stable monomers. However, point mutants assemble as catalytic competent dimers upon binding of the transition state substrate analog PGH, whereas loop 3 deletions remain monomeric. A comparison between crystal structures of point and loop 3 deletion monomeric mutants illustrates that the catalytic residues in point mutants and wild-type TvTIMs are maintained in the same orientation, whereas the catalytic residues in deletion mutants show an increase in thermal mobility and present structural disorder that may hamper their catalytic role. The high enzymatic activity present in monomeric point mutants correlates with the formation of dimeric TvTIMs upon substrate binding. In contrast, the low activity and lack of dimer assembly in deletion mutants suggests a role of loop 3 in promoting the formation of the active site as well as dimer assembly. Our results suggest that in TvTIMs the active site is assembled during dimerization and that the integrity of loop 3 and ball and socket residues is crucial to stabilize the dimer. Copyright © 2017 Elsevier B.V. All rights reserved.

Muscarinic receptor regulates extracellular signal regulated kinase by two modes of arrestin binding.

PubMed

Jung, Seung-Ryoung; Kushmerick, Christopher; Seo, Jong Bae; Koh, Duk-Su; Hille, Bertil

2017-07-11

Binding of agonists to G-protein-coupled receptors (GPCRs) activates heterotrimeric G proteins and downstream signaling. Agonist-bound GPCRs are then phosphorylated by protein kinases and bound by arrestin to trigger desensitization and endocytosis. Arrestin plays another important signaling function. It recruits and regulates activity of an extracellular signal-regulated kinase (ERK) cascade. However, molecular details and timing of ERK activation remain fundamental unanswered questions that limit understanding of how arrestin-dependent GPCR signaling controls cell functions. Here we validate and model a system that tracks the dynamics of interactions of arrestin with receptors and of ERK activation using optical reporters. Our intermolecular FRET measurements in living cells are consistent with β-arrestin binding to M 1 muscarinic acetylcholine receptors (M 1 Rs) in two different binding modes, transient and stable. The stable mode persists for minutes after agonist removal. The choice of mode is governed by phosphorylation on key residues in the third intracellular loop of the receptor. We detect a similar intramolecular conformational change in arrestin in either binding mode. It develops within seconds of arrestin binding to the M 1 receptor, and it reverses within seconds of arrestin unbinding from the transient binding mode. Furthermore, we observed that, when stably bound to phosphorylated M 1 R, β-arrestin scaffolds and activates MEK-dependent ERK. In contrast, when transiently bound, β-arrestin reduces ERK activity via recruitment of a protein phosphatase. All this ERK signaling develops at the plasma membrane. In this scaffolding hypothesis, a shifting balance between the two arrestin binding modes determines the degree of ERK activation at the membrane.

Muscarinic receptor regulates extracellular signal regulated kinase by two modes of arrestin binding

PubMed Central

Jung, Seung-Ryoung; Kushmerick, Christopher; Seo, Jong Bae; Koh, Duk-Su

2017-01-01

Binding of agonists to G-protein–coupled receptors (GPCRs) activates heterotrimeric G proteins and downstream signaling. Agonist-bound GPCRs are then phosphorylated by protein kinases and bound by arrestin to trigger desensitization and endocytosis. Arrestin plays another important signaling function. It recruits and regulates activity of an extracellular signal-regulated kinase (ERK) cascade. However, molecular details and timing of ERK activation remain fundamental unanswered questions that limit understanding of how arrestin-dependent GPCR signaling controls cell functions. Here we validate and model a system that tracks the dynamics of interactions of arrestin with receptors and of ERK activation using optical reporters. Our intermolecular FRET measurements in living cells are consistent with β-arrestin binding to M1 muscarinic acetylcholine receptors (M1Rs) in two different binding modes, transient and stable. The stable mode persists for minutes after agonist removal. The choice of mode is governed by phosphorylation on key residues in the third intracellular loop of the receptor. We detect a similar intramolecular conformational change in arrestin in either binding mode. It develops within seconds of arrestin binding to the M1 receptor, and it reverses within seconds of arrestin unbinding from the transient binding mode. Furthermore, we observed that, when stably bound to phosphorylated M1R, β-arrestin scaffolds and activates MEK-dependent ERK. In contrast, when transiently bound, β-arrestin reduces ERK activity via recruitment of a protein phosphatase. All this ERK signaling develops at the plasma membrane. In this scaffolding hypothesis, a shifting balance between the two arrestin binding modes determines the degree of ERK activation at the membrane. PMID:28652372

Hydrogen production via reforming of biogas over nanostructured Ni/Y catalyst: Effect of ultrasound irradiation and Ni-content on catalyst properties and performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharifi, Mahdi; Reactor and Catalysis Research Center; Haghighi, Mohammad, E-mail: haghighi@sut.ac.ir

2014-12-15

Highlights: • Synthesis of nanostructured Ni/Y catalyst by sonochemical and impregnation methods. • Enhancement of size distribution and active phase dispersion by employing sonochemical method. • Evaluation of biogas reforming over Ni/Y catalyst with different Ni-loadings. • Preparation of highly active and stable catalyst with low Ni content for biogas reforming. • Getting H{sub 2}/CO very close to equilibrium ratio by employing sonochemical method. - Abstract: The effect of ultrasound irradiation and various Ni-loadings on dispersion of active phase over zeolite Y were evaluated in biogas reforming for hydrogen production. X-ray diffraction, field emission scanning electron microscopy, energy dispersive X-ray,more » Brunauer–Emmett–Teller, Fourier transform infrared analysis and TEM analysis were employed to observe the characteristics of nanostructured catalysts. The characterizations implied that utilization of ultrasound irradiation enhanced catalyst physicochemical properties including high dispersion of Ni on support, smallest particles size and high catalyst surface area. The reforming reactions were carried out at GHSV = 24 l/g.h, P = 1 atm, CH{sub 4}/CO{sub 2} = 1 and temperature range of 550–850 °C. Activity test displayed that ultrasound irradiated Ni(5 wt.%)/Y had the best performance and the activity remained stable during 600 min. Furthermore, the proposed reaction mechanism showed that there are three major reaction channels in biogas reforming.« less

Incident diagnoses of cancers and cancer-related deaths, active component, U.S. Armed Forces, 2000-2011.

PubMed

2012-06-01

In the United States, cancer is one of the five leading causes of death in all age groups among both men and women; overall, approximately one in four deaths is attributable to cancer. Compared to the general U.S. population, military members have been estimated to have lower incidence rates of several cancers including colorectal, lung, and cervical cancers and higher rates of prostate, breast, and thyroid cancer. Between 2000 and 2011 in active component members of the U.S. military, crude incidence rates of most cancer diagnoses have remained stable. 9,368 active component service members were diagnosed with one of the cancers of interest and no specific increasing or decreasing trends were observed. Cancer is an uncommon cause of death among service members on active duty and accounted for a total of 1,185 deaths during the 12-year surveillance period.

The relationship between solar activity and coronal hole evolution

NASA Technical Reports Server (NTRS)

Nolte, J. T.; Davis, J. M.; Gerassimenko, M.; Krieger, A. S.; Solodyna, C. V.; Golub, L.

1978-01-01

The relationship between coronal hole evolution and solar active regions during the Skylab period is examined. A tendency is found for holes to grow or remain stable when the activity nearby, seen as calcium plages and bright regions in X-rays, is predominantly large, long-lived regions. It is also found that there is a significantly higher number of small, short-lived active regions, as indicated by X-ray bright points, in the vicinity of decaying holes than there is near other holes. This is interpreted to mean that holes disappear at least in part because they become filled with many small scale, magnetically closed, X-ray emitting features. This interpretation, together with the observation that the number of X-ray bright points was much larger near solar minimum than it was during the Skylab period, provides a possible explanation for the disappearance of the large, near-equatorial coronal holes at the time of solar minimum.

Effects of boiling and in vitro gastrointestinal digestion on the antioxidant activity of Sonchus oleraceus leaves.

PubMed

Mawalagedera, S M M R; Ou, Zong-Quan; McDowell, Arlene; Gould, Kevin S

2016-03-01

Leaves of Sonchus oleraceus L. are especially rich in phenolic compounds and have potent extractable antioxidants. However, it is not known how their antioxidant activity changes after cooking and gastrointestinal digestion. We recorded the profile of phenolics and their associated antioxidant activity in both raw and boiled S. oleraceus leaf extracts after in vitro gastric and intestinal digestion, and quantified their antioxidant potentials using Caco-2 and HepG2 cells. Boiling significantly diminished the oxygen radical absorbance capacity (ORAC) and concentrations of ascorbate and chicoric acid in the soluble fractions. In contrast, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and concentrations of caftaric and chlorogenic acids were unaffected. Phenolics in the soluble fraction were absorbed into cultured human cells and exerted antioxidant activity. Only chlorogenic acid content remained stable during gastrointestinal digestion. S. oleraceus appears to be an excellent dietary source of phenolic antioxidants.

Developing, implementing, and evaluating a condom promotion program targeting sexually active adolescents.

PubMed

Alstead, M; Campsmith, M; Halley, C S; Hartfield, K; Goldbaum, G; Wood, R W

1999-12-01

This article describes the development, implementation, and evaluation of the Condom Campaign, a 1995 HIV prevention program promoting condom use among sexually active adolescents in three King County, Washington, urban communities. This program employed three main strategies: (a) mobilizing all levels of the target communities to support and guide program development and implementation; (b) creating and implementing a mass media campaign targeting sexually active teenagers that promoted correct condom use and favorable attitudes toward condoms; and (c) recruiting public agencies, community organizations, and businesses to distribute condoms from bins and vending machines. We evaluated the program through a series of cross-sectional interviews conducted in the three communities chosen for their elevated levels of adolescent sexual risk behavior. Overall, 73% of target youth reported exposure to the Condom Campaign; exposure did not differ by age, gender, race, or level of sexual experience. Levels of sexual activity remained stable throughout the media campaign.

Ultrathin dendrimer-graphene oxide composite film for stable cycling lithium-sulfur batteries.

PubMed

Liu, Wen; Jiang, Jianbing; Yang, Ke R; Mi, Yingying; Kumaravadivel, Piranavan; Zhong, Yiren; Fan, Qi; Weng, Zhe; Wu, Zishan; Cha, Judy J; Zhou, Henghui; Batista, Victor S; Brudvig, Gary W; Wang, Hailiang

2017-04-04

Lithium-sulfur batteries (Li-S batteries) have attracted intense interest because of their high specific capacity and low cost, although they are still hindered by severe capacity loss upon cycling caused by the soluble lithium polysulfide intermediates. Although many structure innovations at the material and device levels have been explored for the ultimate goal of realizing long cycle life of Li-S batteries, it remains a major challenge to achieve stable cycling while avoiding energy and power density compromises caused by the introduction of significant dead weight/volume and increased electrochemical resistance. Here we introduce an ultrathin composite film consisting of naphthalimide-functionalized poly(amidoamine) dendrimers and graphene oxide nanosheets as a cycling stabilizer. Combining the dendrimer structure that can confine polysulfide intermediates chemically and physically together with the graphene oxide that renders the film robust and thin (<1% of the thickness of the active sulfur layer), the composite film is designed to enable stable cycling of sulfur cathodes without compromising the energy and power densities. Our sulfur electrodes coated with the composite film exhibit very good cycling stability, together with high sulfur content, large areal capacity, and improved power rate.

Novel phases and superconductivity of tin sulfide compounds

NASA Astrophysics Data System (ADS)

Gonzalez, Joseph M.; Nguyen-Cong, Kien; Steele, Brad A.; Oleynik, Ivan I.

2018-05-01

Tin sulfides, SnxSy, are an important class of materials that are actively investigated as novel photovoltaic and water splitting materials. A first-principles evolutionary crystal structure search is performed with the goal of constructing the complete phase diagram of SnxSy and discovering new phases as well as new compounds of varying stoichiometry at ambient conditions and pressures up to 100 GPa. The ambient phase of SnS2 with P 3 ¯ m 1 symmetry remains stable up to 28 GPa. Another ambient phase, SnS, experiences a series of phase transformations including α-SnS to β-SnS at 9 GPa, followed by β-SnS to γ-SnS at 40 GPa. γ-SnS is a new high-pressure metallic phase with P m 3 ¯ m space group symmetry stable up to 100 GPa, which becomes a superconductor with a maximum Tc = 9.74 K at 40 GPa. Another new metallic compound, Sn3S4 with I 4 ¯ 3 d space group symmetry, is predicted to be stable at pressures above 15 GPa, which also becomes a superconductor with relatively high Tc = 21.9 K at 30 GPa.

Flotsam samples can help explain the δ13C and δ15N values of invertebrate resting stages in lake sediment

NASA Astrophysics Data System (ADS)

van Hardenbroek, Maarten; Rinta, Päivi; Wooller, Matthew J.; Schilder, Jos; Stötter, Tabea; Heiri, Oliver

2018-06-01

The stable isotopic composition of chitinous remains of Cladocera (water fleas) and freshwater Bryozoa (moss animals) preserved in lake sediment records can provide supporting insights into past environmental and ecosystem changes in lakes. Here we explore whether analyses of these remains isolated from lake flotsam can provide information on the driving variables affecting the isotopic composition of these remains. We collected flotsam in 53 lakes and found enough material in 33 lakes to measure the stable carbon and nitrogen isotope ratios (expressed as δ13C and δ15N values, respectively) of resting stages. These values were compared with lake characteristics, water chemistry measurements, and the isotopic composition of sedimentary organic matter (SOM) in the lakes. Mean δ13C values of cladoceran ephippia and SOM were correlated and both were also negatively correlated with deep water methane concentrations and indicators of lake stratification. This supports the findings of previous studies that methane-derived carbon can provide a significant proportion of carbon entering planktonic food webs. Mean δ15N values of bryozoan statoblasts and SOM were correlated, suggesting that both reflect the δ15N values of phytoplankton. Our results provide information on how environmental variables in lakes can influence the δ13C and δ15N values in resting stages, but flotsam samples can also potentially be used to assess seasonal stable isotope variability of resting stages. Both types of information are important to improve palaeoenvironmental interpretations of stable isotope records based on these remains in lake sediments.

[Fifty years of population growth and absorbing manual labor in Brazil, 1950-2000].

PubMed

Paiva, P D

1986-01-01

The economically active population has grown rapidly in Brazil, resulting either from population growth or increased female participation in the work force. This rhythm of growth will continue at least until the end of this century. The authors suggest that the impact of the recent decline in fertility will be moderate and will only affect the younger age groups. Despite the rapid growth of employment in the processing industry, the relative size of the so-called informal sector has remained stable since 1950. It is further predicted that, given the economically active population's rate of growth and the decrease in employment in agriculture, there will be a great demand for urban employment in the next 20 years.

Drug Therapy for Stable Angina Pectoris.

PubMed

Rousan, Talla A; Mathew, Sunil T; Thadani, Udho

2017-03-01

Chronic stable angina pectoris refers to the predictable, reproducible occurrence of pressure or a choking sensation in the chest or adjacent areas caused by myocardial ischemia in association with physical or emotional stress, and cessation of exertion and or sublingual nitroglycerin invariably relieves the discomfort. It is a common presenting symptom of severe narrowing of one or more coronary arteries, non-obstructive coronary arteries, or even when the coronary arteries are angiographically normal. Patients often avoid activities which precipitate symptoms and have impaired quality of life. Most patients with angina pectoris can be managed with lifestyle changes, especially abstinence from smoking and regular exercise, and anti-anginal drugs. However, the choice of initial or combination antianginals as recommended in the guidelines is not evidence based. In addition, patients with stable angina due to coronary artery disease should also receive aspirin and a statin. Treatment of patients with angina and normal coronary arteries remains to be established. The aim of this article is to provide the readers not only with a guideline-based approach, which varies from one country to another, but also an individual-based approach, which takes into consideration circulatory status and the presence or absence of comorbidities in the treatment decision-making process. This manuscript primarily deals with drug therapy of stable angina pectoris and not coronary artery revascularization, which also provides angina relief but is usually reserved for patients who fail to respond to adequate drug therapy.

Evaluating gull diets: A comparison of conventional methods and stable isotope analysis

USGS Publications Warehouse

Weiser, Emily L.; Powell, Abby N.

2011-01-01

Samples such as regurgitated pellets and food remains have traditionally been used in studies of bird diets, but these can produce biased estimates depending on the digestibility of different foods. Stable isotope analysis has been developed as a method for assessing bird diets that is not biased by digestibility. These two methods may provide complementary or conflicting information on diets of birds, but are rarely compared directly. We analyzed carbon and nitrogen stable isotope ratios of feathers of Glaucous Gull (Larus hyperboreus) chicks from eight breeding colonies in northern Alaska, and used a Bayesian mixing model to generate a probability distribution for the contribution of each food group to diets. We compared these model results with probability distributions from conventional diet samples (pellets and food remains) from the same colonies and time periods. Relative to the stable isotope estimates, conventional analysis often overestimated the contributions of birds and small mammals to gull diets and often underestimated the contributions of fish and zooplankton. Both methods gave similar estimates for the contributions of scavenged caribou, miscellaneous marine foods, and garbage to diets. Pellets and food remains therefore may be useful for assessing the importance of garbage relative to certain other foods in diets of gulls and similar birds, but are clearly inappropriate for estimating the potential impact of gulls on birds, small mammals, or fish. However, conventional samples provide more species-level information than stable isotope analysis, so a combined approach would be most useful for diet analysis and assessing a predator's impact on particular prey groups.

France's Administrative Tertiary: Stable Numbers for Occupations in Flux.

ERIC Educational Resources Information Center

Liaroutzos, Olivier; Meriot, Sylvie-Anne

1995-01-01

During the past decade, the number of jobs in France's administrative service sector has remained stable. General administrative work has become more infrequent; however, the basic occupations of secretary and accountancy have been maintained. Although the number of typists has declined, the number of "secretarial" jobs has increased…

Robustly photogenerating H2 in water using FeP/CdS catalyst under solar irradiation

PubMed Central

Cheng, Huanqing; Lv, Xiao-Jun; Cao, Shuang; Zhao, Zong-Yan; Chen, Yong; Fu, Wen-Fu

2016-01-01

Photosplitting water for H2 production is a promising, sustainable approach for solar-to-chemical energy conversion. However, developing low-cost, high efficient and stable photocatalysts remains the major challenge. Here we report a composite photocatalyst consisting of FeP nanoparticles and CdS nanocrystals (FeP/CdS) for photogenerating H2 in aqueous lactic acid solution under visible light irradiation. Experimental results demonstrate that the photocatalyst is highly active with a H2-evolution rate of 202000 μmol h−1 g−1 for the first 5 h (106000 μmol h−1 g−1 under natural solar irradiation), which is the best H2 evolution activity, even 3-fold higher than the control in situ photo-deposited Pt/CdS system, and the corresponding to an apparent quantum efficiency of over 35% at 520 nm. More important, we found that the system exhibited excellent stability and remained effective after more than 100 h in optimal conditions under visible light irradiation. A wide-ranging analysis verified that FeP effectively separates the photoexcited charge from CdS and showed that the dual active sites in FeP enhance the activity of FeP/CdS photocatalysts. PMID:26818001

The cytoprotective enzyme heme oxygenase-1 suppresses Ebola virus replication.

PubMed

Hill-Batorski, Lindsay; Halfmann, Peter; Neumann, Gabriele; Kawaoka, Yoshihiro

2013-12-01

Ebola virus (EBOV) is the causative agent of a severe hemorrhagic fever in humans with reported case fatality rates as high as 90%. There are currently no licensed vaccines or antiviral therapeutics to combat EBOV infections. Heme oxygenase-1 (HO-1), an enzyme that catalyzes the rate-limiting step in heme degradation, has antioxidative properties and protects cells from various stresses. Activated HO-1 was recently shown to have antiviral activity, potently inhibiting the replication of viruses such as hepatitis C virus and human immunodeficiency virus. However, the effect of HO-1 activation on EBOV replication remains unknown. To determine whether the upregulation of HO-1 attenuates EBOV replication, we treated cells with cobalt protoporphyrin (CoPP), a selective HO-1 inducer, and assessed its effects on EBOV replication. We found that CoPP treatment, pre- and postinfection, significantly suppressed EBOV replication in a manner dependent upon HO-1 upregulation and activity. In addition, stable overexpression of HO-1 significantly attenuated EBOV growth. Although the exact mechanism behind the antiviral properties of HO-1 remains to be elucidated, our data show that HO-1 upregulation does not attenuate EBOV entry or budding but specifically targets EBOV transcription/replication. Therefore, modulation of the cellular enzyme HO-1 may represent a novel therapeutic strategy against EBOV infection.

Robustly photogenerating H2 in water using FeP/CdS catalyst under solar irradiation

NASA Astrophysics Data System (ADS)

Cheng, Huanqing; Lv, Xiao-Jun; Cao, Shuang; Zhao, Zong-Yan; Chen, Yong; Fu, Wen-Fu

2016-01-01

Photosplitting water for H2 production is a promising, sustainable approach for solar-to-chemical energy conversion. However, developing low-cost, high efficient and stable photocatalysts remains the major challenge. Here we report a composite photocatalyst consisting of FeP nanoparticles and CdS nanocrystals (FeP/CdS) for photogenerating H2 in aqueous lactic acid solution under visible light irradiation. Experimental results demonstrate that the photocatalyst is highly active with a H2-evolution rate of 202000 μmol h-1 g-1 for the first 5 h (106000 μmol h-1 g-1 under natural solar irradiation), which is the best H2 evolution activity, even 3-fold higher than the control in situ photo-deposited Pt/CdS system, and the corresponding to an apparent quantum efficiency of over 35% at 520 nm. More important, we found that the system exhibited excellent stability and remained effective after more than 100 h in optimal conditions under visible light irradiation. A wide-ranging analysis verified that FeP effectively separates the photoexcited charge from CdS and showed that the dual active sites in FeP enhance the activity of FeP/CdS photocatalysts.

Leucaena sp. recombinant cinnamyl alcohol dehydrogenase: purification and physicochemical characterization.

PubMed

Patel, Parth; Gupta, Neha; Gaikwad, Sushama; Agrawal, Dinesh C; Khan, Bashir M

2014-02-01

Cinnamyl alcohol dehydrogenase is a broad substrate specificity enzyme catalyzing the final step in monolignol biosynthesis, leading to lignin formation in plants. Here, we report characterization of a recombinant CAD homologue (LlCAD2) isolated from Leucaena leucocephala. LlCAD2 is 80 kDa homo-dimer associated with non-covalent interactions, having substrate preference toward sinapaldehyde with Kcat/Km of 11.6×10(6) (M(-1) s(-1)), and a possible involvement of histidine at the active site. The enzyme remains stable up to 40 °C, with the deactivation rate constant (Kd(*)) and half-life (t1/2) of 0.002 and 5h, respectively. LlCAD2 showed optimal activity at pH 6.5 and 9 for reduction and oxidation reactions, respectively, and was stable between pH 7 and 9, with the deactivation rate constant (Kd(*)) and half-life (t1/2) of 7.5×10(-4) and 15 h, respectively. It is a Zn-metalloenzyme with 4 Zn(2+) per dimer, however, was inhibited in presence of externally supplemented Zn(2+) ions. The enzyme was resistant to osmolytes, reducing agents and non-ionic detergents. Copyright © 2013 Elsevier B.V. All rights reserved.

Targeting Stable Rotors to Treat Atrial Fibrillation.

PubMed

Narayan, Sanjiv M; Krummen, David E

2012-09-01

Therapy for atrial fibrillation (AF) remains suboptimal, in large part because its mechanisms are unclear. While pulmonary vein ectopy may trigger AF, it remains uncertain how AF, once triggered, is actually sustained. Recent discoveries show that human AF is maintained by a small number of rotors or focal sources. AF sources are widely distributed in patient-specific locations, often remote from pulmonary veins and in the right atrium and stable for prolonged periods of time. In a multicentre experience, brief targeted ablation at sources (focal impulse and rotor modulation [FIRM]) terminated AF predominantly to sinus rhythm prior to pulmonary vein isolation and eliminated AF on rigorous followup. This review summarises the evidence for stable rotors and focal sources of human AF and their clinical role as ablation targets to eliminate paroxysmal, persistent and long-standing persistent AF.

Cardiac rehabilitation and mid-term follow-up after transcatheter aortic valve implantation

PubMed Central

Zanettini, Renzo; Gatto, Gemma; Mori, Ileana; Pozzoni, Maria Beatrice; Pelenghi, Stefano; Martinelli, Luigi; Klugmann, Silvio

2014-01-01

Background Evaluation of patient outcomes following transcatheter aortic valve implantation (TAVI) has usually been based on survival and clinical improvement. Studies on quality of life are limited, and data from comprehensive assessments after the procedure are lacking. Methods Sixty patients referred for cardiac rehabilitation after TAVI underwent in-hospital and after-discharge multidimensional assessments to evaluate clinical, functional, and nutritional statuses, degree of autonomy, cognitive impairment, depression and quality of life. Results On admission to rehabilitation, approximately half of the patients had severe functional impairment and dependence for basic activities of daily living. During their hospital stay, one-third of the patients suffered significant clinical complications and two had to be transferred to the implantation center. Despite this, the overall outcome was very good. All of the remaining patients were clinically stable at discharge and functional status, autonomy and quality of life were improved in most. During a mean follow-up of 540 days (range: 192–738 days), five patients died from noncardiac causes, three were hospitalized for cardiac events, and nine for non cardiac reasons. Functional status and autonomy remained satisfactory in the majority of patients and most continued to live independently. Conclusions Patients referred for rehabilitation after TAVI are often very frail, with a high grade of functional impairment, dependence on others and high risk of clinical complications. During a rehabilitation programme, based on a multidimensional assessment and intervention, most patients showed significant improvement in functional status, quality of life, and autonomy, which remained stable in the majority of subjects during mid-term follow-up. PMID:25593575

Efficient production of a gene mutant cell line through integrating TALENs and high-throughput cell cloning.

PubMed

Sun, Changhong; Fan, Yu; Li, Juan; Wang, Gancheng; Zhang, Hanshuo; Xi, Jianzhong Jeff

2015-02-01

Transcription activator-like effectors (TALEs) are becoming powerful DNA-targeting tools in a variety of mammalian cells and model organisms. However, generating a stable cell line with specific gene mutations in a simple and rapid manner remains a challenging task. Here, we report a new method to efficiently produce monoclonal cells using integrated TALE nuclease technology and a series of high-throughput cell cloning approaches. Following this method, we obtained three mTOR mutant 293T cell lines within 2 months, which included one homozygous mutant line. © 2014 Society for Laboratory Automation and Screening.

Asymmetry and basic pathways in sleep-stage transitions

NASA Astrophysics Data System (ADS)

Lo, Chung-Chuan; Bartsch, Ronny P.; Ivanov, Plamen Ch.

2013-04-01

We study dynamical aspects of sleep micro-architecture. We find that sleep dynamics exhibits a high degree of asymmetry, and that the entire class of sleep-stage transition pathways underlying the complexity of sleep dynamics throughout the night can be characterized by two independent asymmetric transition paths. These basic pathways remain stable under sleep disorders, even though the degree of asymmetry is significantly reduced. Our findings demonstrate an intriguing temporal organization in sleep micro-architecture at short time scales that is typical for physical systems exhibiting self-organized criticality (SOC), and indicates nonequilibrium critical dynamics in brain activity during sleep.

Direct demonstration of persistent Na+ channel activity in dendritic processes of mammalian cortical neurones

PubMed Central

Magistretti, Jacopo; Ragsdale, David S; Alonso, Angel

1999-01-01

Single Na+ channel activity was recorded in patch-clamp, cell-attached experiments performed on dendritic processes of acutely isolated principal neurones from rat entorhinal-cortex layer II. The distances of the recording sites from the soma ranged from ≈20 to ≈100 μm.Step depolarisations from holding potentials of −120 to −100 mV to test potentials of −60 to +10 mV elicited Na+ channel openings in all of the recorded patches (n= 16).In 10 patches, besides transient Na+ channel openings clustered within the first few milliseconds of the depolarising pulses, prolonged and/or late Na+ channel openings were also regularly observed. This ‘persistent’ Na+ channel activity produced net inward, persistent currents in ensemble-average traces, and remained stable over the entire duration of the experiments (≈9 to 30 min).Two of these patches contained <= 3 channels. In these cases, persistent Na+ channel openings could be attributed to the activity of one single channel.The voltage dependence of persistent-current amplitude in ensemble-average traces closely resembled that of whole-cell, persistent Na+ current expressed by the same neurones, and displayed the same characteristic low threshold of activation.Dendritic, persistent Na+ channel openings had relatively high single-channel conductance (≈20 pS), similar to what is observed for somatic, persistent Na+ channels.We conclude that a stable, persistent Na+ channel activity is expressed by proximal dendrites of entorhinal-cortex layer II principal neurones, and can contribute a significant low-threshold, persistent Na+ current to the dendritic processing of excitatory synaptic inputs. PMID:10601494

Plackett-Burman Design for rGILCC1 Laccase Activity Enhancement in Pichia pastoris: Concentrated Enzyme Kinetic Characterization.

PubMed

Morales-Álvarez, Edwin D; Rivera-Hoyos, Claudia M; Cardozo-Bernal, Ángela M; Poutou-Piñales, Raúl A; Pedroza-Rodríguez, Aura M; Díaz-Rincón, Dennis J; Rodríguez-López, Alexander; Alméciga-Díaz, Carlos J; Cuervo-Patiño, Claudia L

2017-01-01

Laccases are multicopper oxidases that catalyze aromatic and nonaromatic compounds with concomitant reduction of molecular oxygen to water. They are of great interest due to their potential biotechnological applications. In this work we statistically improved culture media for recombinant GILCC1 (rGILCC1) laccase production at low scale from Ganoderma lucidum containing the construct pGAPZ α A- GlucPost -Stop in Pichia pastoris . Temperature, pH stability, and kinetic parameter characterizations were determined by monitoring concentrate enzyme oxidation at different ABTS substrate concentrations. Plackett-Burman Design allowed improving enzyme activity from previous work 36.08-fold, with a laccase activity of 4.69 ± 0.39 UL -1 at 168 h of culture in a 500 mL shake-flask. Concentrated rGILCC1 remained stable between 10 and 50°C and retained a residual enzymatic activity greater than 70% at 60°C and 50% at 70°C. In regard to pH stability, concentrated enzyme was more stable at pH 4.0 ± 0.2 with a residual activity greater than 90%. The lowest residual activity greater than 55% was obtained at pH 10.0 ± 0.2. Furthermore, calculated apparent enzyme kinetic parameters were a V max of 6.87 × 10 -5  mM s -1 , with an apparent K m of 5.36 × 10 -2  mM. Collectively, these important stability findings open possibilities for applications involving a wide pH and temperature ranges.

Plackett-Burman Design for rGILCC1 Laccase Activity Enhancement in Pichia pastoris: Concentrated Enzyme Kinetic Characterization

PubMed Central

Morales-Álvarez, Edwin D.; Rivera-Hoyos, Claudia M.; Cardozo-Bernal, Ángela M.; Pedroza-Rodríguez, Aura M.; Díaz-Rincón, Dennis J.; Rodríguez-López, Alexander; Alméciga-Díaz, Carlos J.; Cuervo-Patiño, Claudia L.

2017-01-01

Laccases are multicopper oxidases that catalyze aromatic and nonaromatic compounds with concomitant reduction of molecular oxygen to water. They are of great interest due to their potential biotechnological applications. In this work we statistically improved culture media for recombinant GILCC1 (rGILCC1) laccase production at low scale from Ganoderma lucidum containing the construct pGAPZαA-GlucPost-Stop in Pichia pastoris. Temperature, pH stability, and kinetic parameter characterizations were determined by monitoring concentrate enzyme oxidation at different ABTS substrate concentrations. Plackett-Burman Design allowed improving enzyme activity from previous work 36.08-fold, with a laccase activity of 4.69 ± 0.39 UL−1 at 168 h of culture in a 500 mL shake-flask. Concentrated rGILCC1 remained stable between 10 and 50°C and retained a residual enzymatic activity greater than 70% at 60°C and 50% at 70°C. In regard to pH stability, concentrated enzyme was more stable at pH 4.0 ± 0.2 with a residual activity greater than 90%. The lowest residual activity greater than 55% was obtained at pH 10.0 ± 0.2. Furthermore, calculated apparent enzyme kinetic parameters were a Vmax of 6.87 × 10−5 mM s−1, with an apparent Km of 5.36 × 10−2 mM. Collectively, these important stability findings open possibilities for applications involving a wide pH and temperature ranges. PMID:28421142

App Usage Factor: A Simple Metric to Compare the Population Impact of Mobile Medical Apps.

PubMed

Lewis, Thomas Lorchan; Wyatt, Jeremy C

2015-08-19

One factor when assessing the quality of mobile apps is quantifying the impact of a given app on a population. There is currently no metric which can be used to compare the population impact of a mobile app across different health care disciplines. The objective of this study is to create a novel metric to characterize the impact of a mobile app on a population. We developed the simple novel metric, app usage factor (AUF), defined as the logarithm of the product of the number of active users of a mobile app with the median number of daily uses of the app. The behavior of this metric was modeled using simulated modeling in Python, a general-purpose programming language. Three simulations were conducted to explore the temporal and numerical stability of our metric and a simulated app ecosystem model using a simulated dataset of 20,000 apps. Simulations confirmed the metric was stable between predicted usage limits and remained stable at extremes of these limits. Analysis of a simulated dataset of 20,000 apps calculated an average value for the app usage factor of 4.90 (SD 0.78). A temporal simulation showed that the metric remained stable over time and suitable limits for its use were identified. A key component when assessing app risk and potential harm is understanding the potential population impact of each mobile app. Our metric has many potential uses for a wide range of stakeholders in the app ecosystem, including users, regulators, developers, and health care professionals. Furthermore, this metric forms part of the overall estimate of risk and potential for harm or benefit posed by a mobile medical app. We identify the merits and limitations of this metric, as well as potential avenues for future validation and research.

Efficacy of 99mTc-EDDA/HYNIC-TOC scintigraphy in differential diagnosis of solitary pulmonary nodules.

PubMed

Płachcińska, Anna; Mikołajczak, Renata; Maecke, Helmut; Kozak, Józef; Michalski, Andrzej; Rzeszutek, Katarzyna; Kuśmierek, Jacek

2004-10-01

Fifty consecutive patients with solitary pulmonary nodules (SPN) on chest radiographs were studied scintigraphically after the administration of a somatostatin analog 99mTc-EDDA/HYNIC-TOC. The activity amounted to 740-925 MBq and a single photon emission computed tomography (SPECT) technique was applied. Verification of the nodule etiology was based on histology or cytology and bacteriology. As additional criterion for nodule benignity, its stable size in a chest radiograph for at least 3 years was accepted. In 31 patients, malignant etiologies of nodules were found. The diagnoses included: 11 adenocarcinomas, 6 squamous-cell carcinomas, 2 large-cell carcinomas, 6 nonsmall-cell lung cancers (NSCLC) of unspecified, more detailed morphology, 2 small-cell lung cancers (SCLC), 2 typical carcinoids, and 2 metastatic tumors: leiomyosarcoma and malignant melanoma. In 19 patients, the following benign tumors were diagnosed: 6 tuberculomas, 2 other granulomas, 4 hamartomas, 2 nonspecific inflammatory infiltrates, 1 abscess, 1 peripheral carcinoid of morphological characteristics of a benign tumor, 1 ectopic lesion of thyroid tissue, and 2 benign tumors of unspecified etiology, with stable size over 3 and 5 years. Positive scintigraphic results were obtained in 28 of 31 patients (90%) with malignant SPNs; among these there were 26 of 27 (96%) cases of primary pulmonary carcinoma. The remaining 2 false-negative cases included metastatic tumors: liposarcoma and melanoma. Among 19 benign lesions, 15 (79%) did not accumulate the radiopharmaceutical. The remaining 4 tumors visible on scintigrams included: 1 tuberculoma, 1 hamartoma, 1 abscess, and 1 case of nonestablished diagnosis (with stable size over 3 years). In conclusion, scintigraphy with 99mTc-EDDA/HYNIC-TOC appears to be an effective procedure for differentiation between malignant and benign SPNs.

Influence of palmitoyl pentapeptide and Ceramide III B on the droplet size of nanoemulsion

NASA Astrophysics Data System (ADS)

Sondari, Dewi; Haryono, Agus; Harmami, Sri Budi; Randy, Ahmad

2010-05-01

The influence of the Palmitoyl Pentapeptide (PPp) and Ceramide IIIB (Cm III B) as active ingredients on the droplet size of nano-emulsion was studied using different kinds of oil (avocado oil, sweet almond oil, jojoba oil, mineral oil and squalene). The formation of nano-emulsions were prepared in water mixed non ionic surfactant/oils system using the spontaneous emulsification mechanism. The aqueous solution, which consist of water and Tween® 20 as a hydrophilic surfactant was mixed homogenously. The organic solution, which consist of oil and Span® 80 as a lipophilic surfactant was mixed homogenously in ethanol. Ethanol was used as a water miscible solvent, which can help the formation of nano-emulsion. The oil phase (containing the blend of surfactant Span® 80, ethanol, oil and active ingredient) and the aqueous phase (containing water and Tween® 20) were separately prepared at room temperatures. The oil phase was slowly added into aqueous phase under continuous mechanical agitation (18000 rpm). All samples were subsequently homogenized with Ultra-Turrax for 30 minutes. The characterizations of nano-emulsion were carried out using photo-microscope and particle size analyzer. Addition of active ingredients on the formation of nano-emulsion gave smallest droplet size compared without active ingredients addition on the formation of nano-emulsion. Squalene oil with Palmitoyl Pentapeptide (PPm) and Ceramide IIIB (Cm IIIB) gave smallest droplet size (184.0 nm) compared without Palmitoyl Pentapeptide and Ceramide IIIB (214.9 nm), however the droplets size of the emulsion prepared by the other oils still in the range of nano-emulsion (below 500 nm). The stability of nano-emulsion was observed using two methods. In one method, the stability of nano-emulsion was observed for three months at temperature of 5°C and 50°C, while in the other method, the stability nano-emulsion was observed by centrifuged at 12000 rpm for 30 minutes. Nanoemulsion with active ingredient was remained stable even when stored until three months. Coalescence process between the droplets was not occurred significantly and droplet size was still below 500 nm. Over all, the emulsion remained stable, even it was centrifuged at 12000 rpm for 30 minutes.

The Effects of Intellectual, Physical, and Social Activity on Further Prognosis in Mild Cognitive Impairment.

PubMed

Bidzan, Leszek; Bidzan, Mariola; Pąchalska, Maria

2016-07-19

BACKGROUND Our goal was to specify the relationship between the level of activity (intellectual, physical, and social) in persons diagnosed with mild cognitive impairment (MCI) and the further progression of cognitive dysfunction. MATERIAL AND METHODS We examined 193 patients diagnosed with MCI (according to the criteria of the Working Group on Mild Cognitive Impairment) and under treatment at our Mental Disorders Clinic. It was assumed that these persons would remain under systematic psychiatric observation until dementia was diagnosed. The present study results from a seven-year observation period. The mini-mental state examination (MMSE), the Activity Scale (with the intellectual, physical, and social subscales), and the Instrumental Activities of Daily Living (IADL) scale were used to evaluate the participants' status at baseline. The MMSE was re-administered after one year and again at the end of the observation (either upon diagnosis of dementia or after seven years). At each meeting with the participant, the clinical diagnosis was verified to determine if the patient had dementia or not. Of the 193 people initially qualified for the study, 75 were available for the final analysis. RESULTS It was found that there was no statistically significant difference in the baseline MMSE scores between the persons with stable MCI and the persons who had progressed to dementia. However, statistically significant differences in the level of activity at baseline on both the global IADL scale and the Activity Scale between those with stable MCI and those who had progressed to dementia were found. These differences were manifested in the IADL subscales for telephone use, shopping, transportation, and personal finances, and in the physical activity subscale. CONCLUSIONS An evaluation of intellectual, physical, and social activity can be useful in determining the prognosis for the future course of MCI.

Quality of Clotting Factor Activity in Fresh Frozen Plasma at Thaw with a Microwave System and after Storage at 4 degrees C for 48 Hours.

PubMed

Kuta, Piotr; Hauck-Dlimi, Barbara; Strobel, Julian; Zimmermann, Robert; Eckstein, Reinhold

2016-01-01

Uncontrolled hemorrhage in polytrauma patients usually results in rapid need of blood products. Despite the shorter thawing times of microwave devices for heating fresh frozen plasma (FFP), their use has remained controversial, and just a few laboratory analyses have been published on this topic. The aim of this study was to analyse the quality of clotting factors immediately after thawing FFP with a microwave device and after 48-hour post thaw storage at 4 degrees C. 24 FFP units of all four ABO blood groups (six of each blood group) were thawed with a Transfusio-therm 2000 and later stored at 4 degrees C for 48 hours. Samples were drawn aseptically and investigated on various clotting factors and protein proteases (fibrinogen, antithrombin, FII, FV, FVII, FVIII, FIX, FX, FXI, FXIII, vWF antigen and activity, protein S, and protein C) using standard coagulation and chromogenic assays immediately after thawing and again after a 48-hour storage period at 4 degrees C. All units were tested for both anaerobic and aerobic microbial contamination using standard operating procedures immediately after thawing. After thawing, all coagulation factors and protein protease activities were within normal ranges. Blood group O individuals had approximately 25% lower plasma levels of vWF antigen and activity. After a 48-hour storage period at 4 degrees C, FVIII and FIX activities declined significantly in all blood groups, whereas the remaining clotting factors remained comparably stable. Immediately after rapid thawing using a microwave system, all FFP units contained adequate coagulation factor activities to maintain hemostatic activity at the time of product thaw. The post thaw refrigerated storage caused an anticipated decrease in factor VIII and IX activities, but retained normal coagulation factor levels of many plasma proteins. Therefore we conclude that the Transfusio-therm 2000 has no clinically significant influence on the activity of clotting factors and plasma proteases in FFP units.

Internal desynchronization in a model of night-work by forced activity in rats.

PubMed

Salgado-Delgado, R; Angeles-Castellanos, M; Buijs, M R; Escobar, C

2008-06-26

Individuals engaged in shift- or night-work show disturbed diurnal rhythms, out of phase with temporal signals associated to the light/dark (LD) cycle, resulting in internal desynchronization. The mechanisms underlying internal desynchrony have been mainly investigated in experimental animals with protocols that induce phase shifts of the LD cycle and thus modify the activity of the suprachiasmatic nucleus (SCN). In this study we developed an animal model of night-work in which the light-day cycle remained stable and rats were required to be active in a rotating wheel for 8 h daily during their sleeping phase (W-SP). This group was compared with rats that were working in the wheel during their activity phase (W-AP) and with undisturbed rats (C). We provide evidence that forced activity during the sleeping phase (W-SP group) alters not only activity, but also the temporal pattern of food intake. In consequence W-SP rats showed a loss of glucose rhythmicity and a reversed rhythm of triacylglycerols. In contrast W-AP rats did not show such changes and exhibited metabolic rhythms similar to those of the controls. The three groups exhibited the nocturnal corticosterone increase, in addition the W-SP and W-AP groups showed increase of plasma corticosterone associated with the start of the working session. Forced activity during the sleep phase did not modify SCN activity characterized by the temporal patterns of PER1 and PER2 proteins, which remained in phase with the LD cycle. These observations indicate that a working regimen during the sleeping period elicits internal desynchronization in which activity combined with feeding uncouples metabolic functions from the biological clock which remains fixed to the LD cycle. The present data suggest that in the night worker the combination of work and eating during working hours may be the cause of internal desynchronization.

Variation of glucose tolerance in adult patients with cystic fibrosis: What is the potential contribution of insulin sensitivity?

PubMed

Boudreau, Valérie; Coriati, Adèle; Hammana, Imane; Ziai, Sophie; Desjardins, Katherine; Berthiaume, Yves; Rabasa-Lhoret, Rémi

2016-11-01

Reduced insulin secretion is a key factor to explain high prevalence of glucose intolerance in patients with cystic fibrosis (CF). However, the role of insulin sensitivity remains unclear. The aim of this study is to investigate the association of insulin secretion and sensitivity with the evolution of glucose tolerance. A total of 152 patients without known diabetes from the Montreal CF cohort underwent two 2-h oral glucose tolerance tests (OGTT) at baseline and again after 21.2±5.5months. Pulmonary function and anthropometric measurements were also collected at each visit. At both visits, based on their OGTT results, patients were categorized in glucose tolerance groups (normal glucose tolerance, impaired glucose tolerance or CF-related diabetes) and stratified in 3 groups according to the variation of their glucose tolerance: stable, improved or deteriorated. At baseline, patients in the deteriorated group had a better sensitivity to insulin than those in the improved group (P=0.029). At follow-up glucose tolerance remained stable in 55.3%, improved in 14.5% and deteriorated in 30.3% of patients. During follow-up, insulin secretion remained stable in all 3 groups. While insulin sensitivity remained stable in patients without changes in glucose tolerance it worsened in patients who deteriorated glucose tolerance (P<0.001) and improved in patients who improved their glucose tolerance (P=0.003). In a context of significantly reduced insulin secretion, variations of insulin sensitivity are associated with variations of glucose tolerance in adult patients with CF. Copyright © 2016 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

Diplogelasinospora grovesii IMI 171018 immobilized in polyurethane foam. An efficient biocatalyst for stereoselective reduction of ketones.

PubMed

Quezada, M A; Carballeira, J D; Sinisterra, J V

2012-05-01

Diplogelasinospora grovesii has been reported as a very active biocatalyst in the reduction of ketones. Along the text, the properties of this filamentous fungus as an immobilized catalyst are described. For this purpose, several immobilization supports as agar and polyurethane foam were tested. Experimental assays were also performed to test different co-substrates for the regeneration of the required enzyme cofactor. The fungus immobilized in polyurethane foam lead to the most stable and active catalyst. This derivative, using i-PrOH as co-substrate, could be reused at least 18 times without appreciable activity loss (>90% activity remains). Kinetic runs experiments shown that the reduction of cyclohexanone, selected as model substrate, followed a pseudo-first kinetic order and that the rate controlling step was the mass transfer through the cell wall. The deactivation kinetic constants were also determined. The reduction of different chiral ketones showed that the ketone reductase activity followed the Prelog's rule. Copyright © 2012 Elsevier Ltd. All rights reserved.

Preliminary evidence for increased parasympathetic activity during social inclusion and exclusion in adolescents with functional abdominal pain.

PubMed

Gulewitsch, Marco Daniel; Jusyte, Aiste; Mazurak, Nazar; Weimer, Katja; Schönenberg, Michael

2017-07-01

Peer victimization (e.g. social exclusion) has been shown to be associated with physical health problems such as functional somatic complaints and especially symptoms of pain. To date, no study has investigated the mechanisms underlying this association in clinical pediatric samples. The aim of this study was to evaluate the parasympathetic activity during a social exclusion experience in adolescents with functional abdominal pain (FAP). Twenty adolecents with FAP and 21 matched healthy participants were compared regarding parameters of parasympathetic activation before, during, and after participating in the Cyberball-game, a well-established paradigm to induce social exclusion. Adolescents with FAP showed an increase in parasympathetic activation during both consecutive phases of the Cyberball game (inclusion as well as exclusion condition) whereas the healthy control group remained stable. There were no differences in subjective experience of in- and exclusion between the groups. The parasympathetic activation pattern may indicate altered processing of social stimuli in adolescents with FAP. Copyright © 2017 Elsevier Inc. All rights reserved.

Electron capture activation of the disulfide bond. The role of the asymmetry and electronegativity.

PubMed

Gámez, José A; Serrano-Andrés, Luis; Yáñez, Manuel

2010-02-07

The effects of electron capture on the structure of XSSX' disulfide derivatives in which the substituents attached to the sulfur atoms have different electronegativites have been investigated at different levels of theory, namely DFT, MP2, QCISD and CASSCF/CASPT2. Although it has been generally assumed that electron attachment to disulfide derivatives leads to a systematic and significant activation of the S-S bond, our results show that this is the case only when the substituents X or X' have low electronegativity. Otherwise, the S-S bond in the anion remains practically unperturbed and only the S-X bond is largely activated or even broken, because the extra electron occupies the sigma*(S-X) rather than the sigma*(S-S) antibonding orbital. Our results also show that S-S activation yields a system with a unique anion, whereas when the S-X activation is significant, two stable anionic species, stretched and bent, are formed.

Enzymatic activity inside and outside of water-stable aggregates in soils under different land use

NASA Astrophysics Data System (ADS)

Garbuz, S. A.; Yaroslavtseva, N. V.; Kholodov, V. A.

2016-03-01

A method is presented for assessing the distribution of enzymatic activity inside and outside of water-stable aggregates. Two samples of water-stable aggregates >1 mm have been isolated from dry aggregates of 1-2 mm. To determine the enzymatic activity, a substrate has been added to one of the samples without disaggregation; the other sample has been preliminarily disaggregated. Enzymatic activity within waterstable aggregates has been assessed from the difference between the obtained results under the supposition that the penetration of substrate within the water-saturated aggregates is hampered, and enzymatic reactions occur only at the periphery. The levels and distributions of enzymatic (peroxidase, polyphenol oxidase, and catalase) activities in water-stable aggregates of soddy-podzolic soils under forest and plowland and typical chernozems of long-term field experiments have been studied. The peroxidase, polyphenol oxidase, and catalase activities of water-stable aggregates vary from 6 to 23, from 7 to 30, and from 5 to 7 mmol/(g h), respectively. The ratio between the enzymatic activities inside and outside of soil aggregates showed a higher dependence on soil type and land use, as well as on the input of organic matter and the structural state, than the general activity level in water-stable aggregates.

Spatiotemporal dynamics of large-scale brain activity

NASA Astrophysics Data System (ADS)

Neuman, Jeremy

Understanding the dynamics of large-scale brain activity is a tough challenge. One reason for this is the presence of an incredible amount of complexity arising from having roughly 100 billion neurons connected via 100 trillion synapses. Because of the extremely high number of degrees of freedom in the nervous system, the question of how the brain manages to properly function and remain stable, yet also be adaptable, must be posed. Neuroscientists have identified many ways the nervous system makes this possible, of which synaptic plasticity is possibly the most notable one. On the other hand, it is vital to understand how the nervous system also loses stability, resulting in neuropathological diseases such as epilepsy, a disease which affects 1% of the population. In the following work, we seek to answer some of these questions from two different perspectives. The first uses mean-field theory applied to neuronal populations, where the variables of interest are the percentages of active excitatory and inhibitory neurons in a network, to consider how the nervous system responds to external stimuli, self-organizes and generates epileptiform activity. The second method uses statistical field theory, in the framework of single neurons on a lattice, to study the concept of criticality, an idea borrowed from physics which posits that in some regime the brain operates in a collectively stable or marginally stable manner. This will be examined in two different neuronal networks with self-organized criticality serving as the overarching theme for the union of both perspectives. One of the biggest problems in neuroscience is the question of to what extent certain details are significant to the functioning of the brain. These details give rise to various spatiotemporal properties that at the smallest of scales explain the interaction of single neurons and synapses and at the largest of scales describe, for example, behaviors and sensations. In what follows, we will shed some light on this issue.

Robust Representation of Stable Object Values in the Oculomotor Basal Ganglia

PubMed Central

Yasuda, Masaharu; Yamamoto, Shinya; Hikosaka, Okihide

2012-01-01

Our gaze tends to be directed to objects previously associated with rewards. Such object values change flexibly or remain stable. Here we present evidence that the monkey substantia nigra pars reticulata (SNr) in the basal ganglia represents stable, rather than flexible, object values. After across-day learning of object–reward association, SNr neurons gradually showed a response bias to surprisingly many visual objects: inhibition to high-valued objects and excitation to low-valued objects. Many of these neurons were shown to project to the ipsilateral superior colliculus. This neuronal bias remained intact even after >100 d without further learning. In parallel with the neuronal bias, the monkeys tended to look at high-valued objects. The neuronal and behavioral biases were present even if no value was associated during testing. These results suggest that SNr neurons bias the gaze toward objects that were consistently associated with high values in one’s history. PMID:23175843

Training the elderly on the ability factors of spatial orientation and inductive reasoning.

PubMed

Willis, S L; Schaie, K W

1986-09-01

We examined the effects of cognitive training with elderly participants from the Seattle Longitudinal Study. Subjects were classified as having remained stable or having declined over the previous 14-year interval on each of two primary abilities, spatial orientation and inductive reasoning. Subjects who had declined on one of these abilities received training on that ability; subjects who had declined on both abilities or who had remained stable on both were randomly assigned to the spatial orientation or inductive reasoning training programs. Training outcomes were examined within an ability-measurement framework with empirically determined factorial structure. Significant training effects, at the level of the latent ability constructs, occurred for both spatial orientation and inductive reasoning. These effects were general, in that no significant interactions with decline status or gender were found. Thus, training interventions were effective both in remediating cognitive decline on the target abilities and in improving the performance of stable subjects.

Highly-efficient liposome-mediated transformation system for the basidiomycetous fungus Flammulina velutipes.

PubMed

Shi, Liang; Chen, Dongdong; Xu, Chao; Ren, Ang; Yu, Hanshou; Zhao, Mingwen

2017-07-11

Flammulina velutipes is a well-known edible mushroom cultivated all over the world. However, because of the low transformation frequency, the expensive instruments required, and the complicated, time-consuming procedures necessary, there is insufficient genetic research on F. velutipes. In this study, we report a liposome-mediated transformation (LMT) system for the genetic transformation of F. velutipes. Using the LMT system, we obtained 82 ± 4 stable F. velutipes transformants per 10 5 protoplasts, which is a clear increase in transformation frequency compared to the other methods used. We were able to detect the expression of an EGFP reporter gene in the F. velutipes transformants using fluorescence imaging assays. Furthermore, we used this method to transfer the laccase gene into F. velutipes and found that the transcriptional level and enzymatic activity increased in these transformants. Mitotic stability analysis showed that all of the selected transformants remained mitotically stable, even after five successive rounds of sub-culturing. These results demonstrate a new transgenic approach that will facilitate F. velutipes research.

Plausible authentication of manuka honey and related products by measuring leptosperin with methyl syringate.

PubMed

Kato, Yoji; Fujinaka, Rie; Ishisaka, Akari; Nitta, Yoko; Kitamoto, Noritoshi; Takimoto, Yosuke

2014-07-09

Manuka honey, obtained from Leptospermum scoparium flowers in New Zealand, has strong antibacterial properties. In this study, plausible authentication of the manuka honey was inspected by measuring leptosperin, methyl syringate 4-O-β-D-gentiobiose, along with methyl syringate. Despite a gradual decrease in methyl syringate content over 30 days at 50 °C, even at moderate 37 °C, leptosperin remained stable. A considerable correlation between nonperoxide antibacterial activity and leptosperin content was observed in 20 certified manuka honey samples. Leptosperin and methyl syringate in manuka honey and related products were analyzed using HPLC connected with mass spectrometry. One noncertified brand displayed significant variations in the leptosperin and methyl syringate contents between two samples obtained from different regions. Therefore, certification is clearly required to protect consumers from disguised and/or low-quality honey. Because leptosperin is stable during storage and specific to manuka honey, its measurement may be applicable for manuka honey authentication.

Uncovering inherent cellular plasticity of multiciliated ependyma leading to ventricular wall transformation and hydrocephalus.

PubMed

Abdi, Khadar; Lai, Chun-Hsiang; Paez-Gonzalez, Patricia; Lay, Mark; Pyun, Joon; Kuo, Chay T

2018-04-25

Specialized, differentiated cells often perform unique tasks that require them to maintain a stable phenotype. Multiciliated ependymal cells (ECs) are unique glial cells lining the brain ventricles, important for cerebral spinal fluid circulation. While functional ECs are needed to prevent hydrocephalus, they have also been reported to generate new neurons: whether ECs represent a stable cellular population remains unclear. Via a chemical screen we found that mature ECs are inherently plastic, with their multiciliated state needing constant maintenance by the Foxj1 transcription factor, which paradoxically is rapidly turned over by the ubiquitin-proteasome system leading to cellular de-differentiation. Mechanistic analyses revealed a novel NF-κB-independent IKK2 activity stabilizing Foxj1 in mature ECs, and we found that known IKK2 inhibitors including viruses and growth factors robustly induced Foxj1 degradation, EC de-differentiation, and hydrocephalus. Although mature ECs upon de-differentiation can divide and regenerate multiciliated ECs, we did not detect evidence supporting EC's neurogenic potential.

Overcoming the Instability of Nanoparticle-Based Catalyst Films in Alkaline Electrolyzers by using Self-Assembling and Self-Healing Films.

PubMed

Barwe, Stefan; Masa, Justus; Andronescu, Corina; Mei, Bastian; Schuhmann, Wolfgang; Ventosa, Edgar

2017-07-10

Engineering stable electrodes using highly active catalyst nanopowders for electrochemical water splitting remains a challenge. We report an innovative and general approach for attaining highly stable catalyst films with self-healing capability based on the in situ self-assembly of catalyst particles during electrolysis. The catalyst particles are added to the electrolyte forming a suspension that is pumped through the electrolyzer. Particles with negatively charged surfaces stick onto the anode, while particles with positively charged surfaces stick to the cathode. The self-assembled catalyst films have self-healing properties as long as sufficient catalyst particles are present in the electrolyte. The proof-of-concept was demonstrated in a non-zero gap alkaline electrolyzer using NiFe-LDH and Ni x B catalyst nanopowders for anode and cathode, respectively. Steady cell voltages were maintained for at least three weeks during continuous electrolysis at 50-100 mA cm -2 . © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Associates of an elevated natriuretic peptide level in stable heart failure patients: implications for targeted management.

PubMed

Jan, Aftab; Dawkins, Ian; Murphy, Niamh; Collier, Patrick; Baugh, John; Ledwidge, Mark; McDonald, Kenneth; Watson, Chris J

2013-01-01

Persistently elevated natriuretic peptide (NP) levels in heart failure (HF) patients are associated with impaired prognosis. Recent work suggests that NP-guided therapy can improve outcome, but the mechanisms behind an elevated BNP remain unclear. Among the potential stimuli for NP in clinically stable patients are persistent occult fluid overload, wall stress, inflammation, fibrosis, and ischemia. The purpose of this study was to identify associates of B-type natriuretic peptide (BNP) in a stable HF population. In a prospective observational study of 179 stable HF patients, the association between BNP and markers of collagen metabolism, inflammation, and Doppler-echocardiographic parameters including left ventricular ejection fraction (LVEF), left atrial volume index (LAVI), and E/e prime (E/e') was measured. Univariable associates of elevated BNP were age, LVEF, LAVI, E/e', creatinine, and markers of collagen turnover. In a multiple linear regression model, age, creatinine, and LVEF remained significant associates of BNP. E/e' and markers of collagen turnover had a persistent impact on BNP independent of these covariates. Multiple variables are associated with persistently elevated BNP levels in stable HF patients. Clarification of the relative importance of NP stimuli may help refine NP-guided therapy, potentially improving outcome for this at-risk population.

A pilot randomized trial to prevent sexual dysfunction in postmenopausal breast cancer survivors starting adjuvant aromatase inhibitor therapy.

PubMed

Advani, Pragati; Brewster, Abenaa M; Baum, George P; Schover, Leslie R

2017-08-01

A randomized pilot trial evaluated the hypothesis that early intervention lessens sexual dysfunction in the first year on aromatase inhibitors. A secondary aim was comparing the efficacy of two vaginal moisturizers. Fifty-seven postmenopausal women with early stage breast cancer starting aromatase inhibitors were randomized to three treatment groups. All received a handout on managing sexual and other side effects. The Usual Care group received no additional therapy. The Active Treatment groups received a 6-month supply of a vaginal moisturizer (hyaluronic acid-based in Active Group-H and prebiotic in Active Group-P) and a vaginal lubricant and dilator, plus access to an educational website and phone coaching. Questionnaires completed at baseline, 6, and 12 months included the Female Sexual Function Index (FSFI), Menopausal Sexual Interest Questionnaire (MSIQ), Female Sexual Distress Scale-Revised (FSDS-R), and a menopausal symptom scale. Forty-nine women (86%) provided follow-up data. Mean age was 59 and 77% were non-Hispanic Caucasian. Sexual function was impaired at baseline, but remained stable over 12 months for all groups. The combined active treatment group had less dyspareunia (P = 0.07) and sexual distress (P = 0.02) at 6 months than the Usual Care group. At 6 months, the Active-H group improved significantly more than the Active-P group on FSFI total score (P = 0.04). Sexual counseling helped women maintain stable sexual function on aromatase inhibitors. Active intervention resulted in better outcomes at 6 months. This promising pilot trial suggests a need for more research on preventive counseling to maintain sexual function during aromatase inhibitor treatment.

Unscrambling the effect of C-terminal tail deletion on the stability of a cold-adapted, organic solvent stable lipase from Staphylococcus epidermidis AT2.

PubMed

Kamarudin, Nor Hafizah Ahmad; Rahman, Raja Noor Zaliha Raja Abd; Ali, Mohd Shukuri Mohamad; Leow, Thean Chor; Basri, Mahiran; Salleh, Abu Bakar

2014-08-01

Terminal moieties of most proteins are long known to be disordered and flexible. To unravel the functional role of these regions on the structural stability and biochemical properties of AT2 lipase, four C-terminal end residues, (Ile-Thr-Arg-Lys) which formed a flexible, short tail-like random-coil segment were targeted for mutation. Swapping of the tail-like region had resulted in an improved crystallizability and anti-aggregation property along with a slight shift of the thermostability profile. The lipolytic activity of mutant (M386) retained by 43 % compared to its wild-type with 18 % of the remaining activity at 45 °C. In silico analysis conducted at 25 and 45 °C was found to be in accordance to the experimental findings in which the RMSD values of M386 were more stable throughout the total trajectory in comparison to its wild-type. Terminal moieties were also observed to exhibit large movement and flexibility as denoted by high RMSF values at both dynamics. Variation in organic solvent stability property was detected in M386 where the lipolytic activity was stimulated in the presence of 25 % (v/v) of DMSO, isopropanol, and diethyl ether. This may be worth due to changes in the surface charge residues at the mutation point which probably involve in protein-solvent interaction.

Ultra-thin MoS₂ coated Ag@Si nanosphere arrays as efficient and stable photocathode for solar-driven hydrogen production.

PubMed

Zhou, Qingwei; Su, Shaoqiang; Hu, Die; Lin, Lin; Yan, Zhibo; Gao, Xingsen; Zhang, Zhang; Liu, Junming

2018-01-02

Solar-driven photoelectrochemical (PEC) water splitting has recently attracted much attention. Silicon (Si) is an ideal light absorber for solar energy conversion. However, the poor stability and inefficient surface catalysis of Si photocathode for hydrogen evolution reaction (HER) have been remained as the key challenges. Alternatively, MoS2 has been reported to exhibit the excellent catalysis performance if sufficient active sites for the HER are available. Here, ultra-thin MoS2 nanoflakes are directly synthesized to coat on the arrays of Ag-core Si-shell nanospheres (Ag@Si NSs) using the chemical vapor deposition (CVD). Due to the high surface area ratio and large curvature of these NSs, the as-grown MoS2 nanoflakes can accommodate more active sites. Meanwhile, the high-quality coating of MoS2 nanoflakes on the Ag@Si NSs protects the photocathode from damage during the PEC reaction. A high efficiency with a photocurrent of 33.3 mA cm-2 at a voltage of -0.4 V vs. the reversible hydrogen electrode is obtained. The as-prepared nanostructure as hydrogen photocathode is evidenced to have high stability over 12 hour PEC performance. This work opens opportunities for composite photocathode with high activity and stability using cheap and stable co-catalysts. © 2017 IOP Publishing Ltd.

Overexpression of an endo-1,4-β-glucanase V gene (EGV) from Trichoderma reesei leads to the accumulation of cellulase activity in transgenic rice.

PubMed

Li, X Y; Liu, F; Hu, Y F; Xia, M; Cheng, B J; Zhu, S W; Ma, Q

2015-12-21

The ectopic expression of cellulase in biomass can reduce the cost of biofuel conversion. This trait modification technique is highly beneficial for biofuel production. In this study, we isolated an endo-1,4-beta-glucanase gene (EGV) from Trichoderma reesei and inserted this gene downstream of a fragment encoding the signal peptide Apo-SP in a modified pCAMBIA1301 vector to obtain an Apo-SP and AsRed fusion protein. Transient expression of this fusion protein in onion epidermal cells showed that the Apo-SP signal was localized to the plastids. EGV transgenic rice plants that did not carry screening marker genes were obtained through overexpression of the pDTB double T-DNA vector. Western blotting showed that EGV was expressed in the dry straw of T0 generation transgenic rice plants and in fresh leaves of the T1 generation. More importantly, our results also showed that the peptide product of EGV in the transgenic plants folded correctly and was capable of digesting the cellulase substrate CMC. Additionally, cellulase activity remained stable in the straw that had been dried at room temperature for three months. This study presents an important technical approach for the development of transgenic rice straw that has stable cellulase activity and can be used for biofuel conversion.

[TRENDS IN THE RATE OF OCCUPATIONAL PHYSICIANS VERSUS MANPOWER IN ISRAEL - STATUS AND SOLUTIONS].

PubMed

Moshe, Shlomo; Chuwers, Patricia; Solomon Cohen, Efrat

2017-06-01

The specialization in occupational health was recognized in Israel in 1990. The number of specialists grew gradually over the years, yet a systematic analysis of occupational health physicians (OHP)/workers' ratio was never conducted. To determine the trends of OHP/workers' ratio in Israel and the future activities needed in order to achieve the standards of developed countries. The socio-demographic data was obtained by personal communication, from the Israeli Association of Occupational Medicine and Maccabi Health Services. The remaining data was obtained from publications of the Ministry of Health and the National Insurance Institute. By March 2014, 157 OHPs were registered in Israel, 104 active specialists and 25 residents. Among the specialists, 78 worked in the Health Maintenance Organizations (HMO), 18 in the public sector (other than HMOs) and 8 in the private sector. Even though the number of workers rises every year, the number of OHP has remained stable in the last 10 years, around 90-100 physicians. The ratio of occupational health physicians/workers in the HMOs is 1:48,000. The ratio of OHP/workers in Israel is comparable to the ratio in developing countries and 8-10 times less in comparison to the developed countries with a Gross Domestic Product (GDP) similar to Israel. The rate has decreased since 2007. The reason for the stable numbers is the lack of payments by the employers and the fact that the subject has been ignored by the regulatory authorities. The way to improve this situation is by doubling the number of residents every year by providing the required resources to support this new arrangement. The funds have to come from the employers, the Ministry of Economy and the Ministry of Health.

Effect of active zinc oxide dispersion on reduced graphite oxide for hydrogen sulfide adsorption at mid-temperature

NASA Astrophysics Data System (ADS)

Song, Hoon Sub; Park, Moon Gyu; Croiset, Eric; Chen, Zhongwei; Nam, Sung Chan; Ryu, Ho-Jung; Yi, Kwang Bok

2013-09-01

Composites of Zinc oxide (ZnO) with reduced graphite oxide (rGO) were synthesized and used as adsorbents for hydrogen sulfide (H2S) at 300 °C. Various characterization methods (TGA, XRD, FT-IR, TEM and XPS) were performed in order to link their H2S adsorption performance to the properties of the adsorbent's surface. Microwave-assisted reduction process of graphite oxide (GO) provided mild reduction environment, allowing oxygen-containing functional groups to remain on the rGO surface. It was confirmed that for the ZnO/rGO synthesize using the microwave-assisted reduction method, the ZnO particle size and the degree of ZnO dispersion remained stable over time at 300 °C, which was not the case for only the ZnO particles themselves. This stable highly dispersed feature allows for sustained high surface area over time. This was confirmed through breakthrough experiments for H2S adsorption where it was found that the ZnO/rGO composite showed almost four times higher ZnO utilization efficiency than ZnO itself. The effect of the H2 and CO2 on H2S adsorption was also investigated. The presence of hydrogen in the H2S stream had a positive effect on the removal of H2S since it allows a reducing environment for Znsbnd O and Znsbnd S bonds, leading to more active sites (Zn2+) to sulfur molecules. On the other hand, the presence of carbon dioxide (CO2) showed the opposite trend, likely due to the oxidation environment and also due to possible competitive adsorption between H2S and CO2.

Mechanisms of Soil Aggregation: a biophysical modeling framework

NASA Astrophysics Data System (ADS)

Ghezzehei, T. A.; Or, D.

2016-12-01

Soil aggregation is one of the main crosscutting concepts in all sub-disciplines and applications of soil science from agriculture to climate regulation. The concept generally refers to adhesion of primary soil particles into distinct units that remain stable when subjected to disruptive forces. It is one of the most sensitive soil qualities that readily respond to disturbances such as cultivation, fire, drought, flooding, and changes in vegetation. These changes are commonly quantified and incorporated in soil models indirectly as alterations in carbon content and type, bulk density, aeration, permeability, as well as water retention characteristics. Soil aggregation that is primarily controlled by organic matter generally exhibits hierarchical organization of soil constituents into stable units that range in size from a few microns to centimeters. However, this conceptual model of soil aggregation as the key unifying mechanism remains poorly quantified and is rarely included in predictive soil models. Here we provide a biophysical framework for quantitative and predictive modeling of soil aggregation and its attendant soil characteristics. The framework treats aggregates as hotspots of biological, chemical and physical processes centered around roots and root residue. We keep track of the life cycle of an individual aggregate from it genesis in the rhizosphere, fueled by rhizodeposition and mediated by vigorous microbial activity, until its disappearance when the root-derived resources are depleted. The framework synthesizes current understanding of microbial life in porous media; water holding and soil binding capacity of biopolymers; and environmental controls on soil organic matter dynamics. The framework paves a way for integration of processes that are presently modeled as disparate or poorly coupled processes, including storage and protection of carbon, microbial activity, greenhouse gas fluxes, movement and storage of water, resistance of soils against erosion.

Periodic optical variability of radio-detected ultracool dwarfs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harding, L. K.; Golden, A.; Singh, Navtej

2013-12-20

A fraction of very low mass stars and brown dwarfs are known to be radio active, in some cases producing periodic pulses. Extensive studies of two such objects have also revealed optical periodic variability, and the nature of this variability remains unclear. Here, we report on multi-epoch optical photometric monitoring of six radio-detected dwarfs, spanning the ∼M8-L3.5 spectral range, conducted to investigate the ubiquity of periodic optical variability in radio-detected ultracool dwarfs. This survey is the most sensitive ground-based study carried out to date in search of periodic optical variability from late-type dwarfs, where we obtained 250 hr of monitoring,more » delivering photometric precision as low as ∼0.15%. Five of the six targets exhibit clear periodicity, in all cases likely associated with the rotation period of the dwarf, with a marginal detection found for the sixth. Our data points to a likely association between radio and optical periodic variability in late-M/early-L dwarfs, although the underlying physical cause of this correlation remains unclear. In one case, we have multiple epochs of monitoring of the archetype of pulsing radio dwarfs, the M9 TVLM 513–46546, spanning a period of 5 yr, which is sufficiently stable in phase to allow us to establish a period of 1.95958 ± 0.00005 hr. This phase stability may be associated with a large-scale stable magnetic field, further strengthening the correlation between radio activity and periodic optical variability. Finally, we find a tentative spin-orbit alignment of one component of the very low mass binary, LP 349–25.« less

Forecasting Hospitalization and Emergency Department Visit Rates for Chronic Obstructive Pulmonary Disease. A Time-Series Analysis.

PubMed

Gershon, Andrea; Thiruchelvam, Deva; Moineddin, Rahim; Zhao, Xiu Yan; Hwee, Jeremiah; To, Teresa

2017-06-01

Knowing trends in and forecasting hospitalization and emergency department visit rates for chronic obstructive pulmonary disease (COPD) can enable health care providers, hospitals, and health care decision makers to plan for the future. We conducted a time-series analysis using health care administrative data from the Province of Ontario, Canada, to determine previous trends in acute care hospitalization and emergency department visit rates for COPD and then to forecast future rates. Individuals aged 35 years and older with physician-diagnosed COPD were identified using four universal government health administrative databases and a validated case definition. Monthly COPD hospitalization and emergency department visit rates per 1,000 people with COPD were determined from 2003 to 2014 and then forecasted to 2024 using autoregressive integrated moving average models. Between 2003 and 2014, COPD prevalence increased from 8.9 to 11.1%. During that time, there were 274,951 hospitalizations and 290,482 emergency department visits for COPD. After accounting for seasonality, we found that monthly COPD hospitalization and emergency department visit rates per 1,000 individuals with COPD remained stable. COPD prevalence was forecasted to increase to 12.7% (95% confidence interval [CI], 11.4-14.1) by 2024, whereas monthly COPD hospitalization and emergency department visit rates per 1,000 people with COPD were forecasted to remain stable at 2.7 (95% CI, 1.6-4.4) and 3.7 (95% CI, 2.3-5.6), respectively. Forecasted age- and sex-stratified rates were also stable. COPD hospital and emergency department visit rates per 1,000 people with COPD have been stable for more than a decade and are projected to remain stable in the near future. Given increasing COPD prevalence, this means notably more COPD health service use in the future.

Economic crisis and changes in drug use in the Spanish economically active population.

PubMed

Colell, Esther; Sánchez-Niubò, Albert; Delclos, George L; Benavides, Fernando G; Domingo-Salvany, Antonia

2015-07-01

To examine changes in the use of alcohol, cannabis and hypnotics/sedatives between two periods (before and during Spain's economic crisis), and to identify differences in the change between employed and unemployed individuals. Using cross-sectional data from four editions of the Spanish Household Survey on Alcohol and Drugs, we selected economically active individuals aged 16-64 years (total sample = 62 440) and defined two periods, pre-crisis [period 1 (P1) = 2005-07] and crisis (P2 = 2009-11). Poisson regression models with robust variance were fitted to obtain prevalence ratios (PR) of heavy and binge drinking and multinomial regression models to obtain relative risk ratios (RRR) of cannabis and hypnotic/sedative use between the two periods, also considering the interaction between period and employment status. While the prevalence of alcohol use remained stable, heavy drinking declined in P2 in men both overall [PR = 0.73; 95% confidence interval (CI) = 0.67-0.79] and in the two age groups (16-34 and 35-64 years), and also in women overall (PR = 0.86; 95% CI = 0.75-0.99) and in the older age group. In contrast, binge drinking increased overall in P2 in men (PR = 1.17; 95% CI = 1.12-1.22) and in women (PR = 1.62; 95% CI = 1.49-1.76), and in both age groups. No differences in the change were observed between employed and unemployed individuals. Overall cannabis use remained stable in P2, but unemployed men and women of the older age group were more likely to have increased sporadic use compared to their employed counterparts (RRR = 2.24; 95% CI = 1.36-3.68 and RRR = 3.21; 95% CI = 1.30-7.93, respectively). Hypnotic/sedative use remained stable in P2 in men, but unemployed men were less likely to have increased heavy use in P2 compared with employed men (RRR = 0.69; 95% CI = 0.49-0.97). In women, heavy use increased in P2 overall and in the older age group, irrespective of employment status. During a period of economic recession in Spain, heavy drinking decreased and binge drinking increased. Sporadic cannabis use increased among older unemployed men and women. Heavy use of hypnotics/sedatives increased among employed men while older women increased use irrespective of employment status. © 2015 Society for the Study of Addiction.

[Sarcopenia: toward its clinical utilisation].

PubMed

Bijlsma, Astrid Y; Meskers, Carel G M; Westendorp, Rudi G J; Maier, Andrea B

2013-01-01

Sarcopenia is a term that was introduced to describe 'low muscle mass'. There is no consensus definition for sarcopenia; a variety of criteria are being used to establish the diagnosis of 'sarcopenia'. Depending on the criteria used, the prevalence of sarcopenia in elderly varies from 7% to over 50%. The presence of sarcopenia often remains unrecognized when the loss of muscle mass is replaced by fat and connective tissue; body weight thus remains stable or even increases. Sarcopenia can be detected by measuring muscle mass with dual-energy X-ray absorptiometry (DEXA) or bioimpedance analysis (BIA). Besides the generation of strength, muscle tissue is an important internal organ involved in protein storage, glucose regulation, hormonal homeostasis and cellular communication. Systemic, cellular, neuromechanical factors and lifestyle are linked to the pathophysiology of sarcopenia. Sarcopenia is associated with higher mortality, dependency in activities of daily living, toxicity of chemotherapy, and disturbed glucose regulation.

Effect of conductive additives to gel electrolytes on activated carbon-based supercapacitors

NASA Astrophysics Data System (ADS)

Barzegar, Farshad; Dangbegnon, Julien K.; Bello, Abdulhakeem; Momodu, Damilola Y.; Johnson, A. T. Charlie; Manyala, Ncholu

2015-09-01

This article is focused on polymer based gel electrolyte due to the fact that polymers are cheap and can be used to achieve extended potential window for improved energy density of the supercapacitor devices when compared to aqueous electrolytes. Electrochemical characterization of a symmetric supercapacitor devices based on activated carbon in different polyvinyl alcohol (PVA) based gel electrolytes was carried out. The device exhibited a maximum energy density of 24 Wh kg-1 when carbon black was added to the gel electrolyte as conductive additive. The good energy density was correlated with the improved conductivity of the electrolyte medium which is favorable for fast ion transport in this relatively viscous environment. Most importantly, the device remained stable with no capacitance lost after 10,000 cycles.

Condylectomy and "surgery first" approach: An expedited treatment for condylar hyperplasia in a patient with facial asymmetry.

PubMed

López, Diego Fernando; Aristizábal, Juan Fernando; Martínez-Smit, Rosana

2017-01-01

Condylar Hyperplasia (CH) is a self-limiting pathology condition that produces severe facial deformity at the expense of mandibular asymmetry. In this case report a 15-year-old female patient was diagnosed with Unilateral Condylar Hiperplasia (UCH) by mean of single-photon emission computed tomography (SPECT) and histological study. A high condylectomy in the right condyle was performed to stop the active status of the hyperplasia. A month after condylectomy, orthognathic jaw impaction and asymmetric mandibular setback surgery was performed with the Surgery First Approach (SFA). After 10 days, orthodontic appointments were made every two weeks during 4 months. The active phase of treatment lasted 14 months. Excellent facial and occlusal outcomes were obtained and after 24 months in retention the results remained stable.

Consolidating the effects of waking and sleep on motor-sequence learning.

PubMed

Brawn, Timothy P; Fenn, Kimberly M; Nusbaum, Howard C; Margoliash, Daniel

2010-10-20

Sleep is widely believed to play a critical role in memory consolidation. Sleep-dependent consolidation has been studied extensively in humans using an explicit motor-sequence learning paradigm. In this task, performance has been reported to remain stable across wakefulness and improve significantly after sleep, making motor-sequence learning the definitive example of sleep-dependent enhancement. Recent work, however, has shown that enhancement disappears when the task is modified to reduce task-related inhibition that develops over a training session, thus questioning whether sleep actively consolidates motor learning. Here we use the same motor-sequence task to demonstrate sleep-dependent consolidation for motor-sequence learning and explain the discrepancies in results across studies. We show that when training begins in the morning, motor-sequence performance deteriorates across wakefulness and recovers after sleep, whereas performance remains stable across both sleep and subsequent waking with evening training. This pattern of results challenges an influential model of memory consolidation defined by a time-dependent stabilization phase and a sleep-dependent enhancement phase. Moreover, the present results support a new account of the behavioral effects of waking and sleep on explicit motor-sequence learning that is consistent across a wide range of tasks. These observations indicate that current theories of memory consolidation that have been formulated to explain sleep-dependent performance enhancements are insufficient to explain the range of behavioral changes associated with sleep.

Study of phenotype evolution during childhood in Marfan syndrome to improve clinical recognition.

PubMed

Stheneur, Chantal; Tubach, Florence; Jouneaux, Marlène; Roy, Carine; Benoist, Gregoire; Chevallier, Bertrand; Boileau, Catherine; Jondeau, Guillaume

2014-03-01

Because diagnosis of Marfan syndrome is difficult during infancy, we used a large cohort of children to describe the evolution of the Marfan syndrome phenotype with age. Two hundred and fifty-nine children carrying an FBN1 gene mutation and fulfilling Ghent criteria were compared with 474 non-Marfan syndrome children. Prevalence of skeletal features changed with aging: prevalence of pectus deformity increased from 43% at 0-6 years to 62% at 15-17 years, wrist signs increased from 28 to 67%, and scoliosis increased from 16 to 59%. Hypermobility decreased from 67 to 47% and pes planus decreased from 73 to 65%. Striae increased from 2 to 84%. Prevalence of ectopia lentis remained stable, varying from 66 to 72%, similar to aortic root dilatation (varying from 75 to 80%). Aortic root dilatation remained stable during follow-up in this population receiving β-blocker therapy. When comparing Marfan syndrome children with non-Marfan syndrome children, height appeared to be a simple and discriminant criterion when it was >3.3 SD above the mean. Ectopia lentis and aortic dilatation were both similarly discriminating. Ectopia lentis and aortic dilatation are the best-discriminating features, but height remains a simple discriminating variable for general practitioners when >3.3 SD above the mean. Mean aortic dilatation remains stable in infancy when children receive a β-blocker.

Seven and up: individual differences in male voice fundamental frequency emerge before puberty and remain stable throughout adulthood

NASA Astrophysics Data System (ADS)

Fouquet, Meddy; Pisanski, Katarzyna; Mathevon, Nicolas; Reby, David

2016-10-01

Voice pitch (the perceptual correlate of fundamental frequency, F0) varies considerably even among individuals of the same sex and age, communicating a host of socially and evolutionarily relevant information. However, due to the almost exclusive utilization of cross-sectional designs in previous studies, it remains unknown whether these individual differences in voice pitch emerge before, during or after sexual maturation, and whether voice pitch remains stable into adulthood. Here, we measured the F0 parameters of men who were recorded once every 7 years from age 7 to 56 as they participated in the British television documentary Up Series. Linear mixed models revealed significant effects of age on all F0 parameters, wherein F0 mean, minimum, maximum and the standard deviation of F0 showed sharp pubertal decreases between age 7 and 21, yet remained remarkably stable after age 28. Critically, men's pre-pubertal F0 at age 7 strongly predicted their F0 at every subsequent adult age, explaining up to 64% of the variance in post-pubertal F0. This finding suggests that between-individual differences in voice pitch that are known to play an important role in men's reproductive success are in fact largely determined by age 7, and may therefore be linked to prenatal and/or pre-pubertal androgen exposure.

Proviruses with Long-Term Stable Expression Accumulate in Transcriptionally Active Chromatin Close to the Gene Regulatory Elements: Comparison of ASLV-, HIV- and MLV-Derived Vectors

PubMed Central

Miklík, Dalibor; Šenigl, Filip; Hejnar, Jiří

2018-01-01

Individual groups of retroviruses and retroviral vectors differ in their integration site preference and interaction with the host genome. Hence, immediately after infection genome-wide distribution of integrated proviruses is non-random. During long-term in vitro or persistent in vivo infection, the genomic position and chromatin environment of the provirus affects its transcriptional activity. Thus, a selection of long-term stably expressed proviruses and elimination of proviruses, which have been gradually silenced by epigenetic mechanisms, helps in the identification of genomic compartments permissive for proviral transcription. We compare here the extent and time course of provirus silencing in single cell clones of the K562 human myeloid lymphoblastoma cell line that have been infected with retroviral reporter vectors derived from avian sarcoma/leukosis virus (ASLV), human immunodeficiency virus type 1 (HIV) and murine leukaemia virus (MLV). While MLV proviruses remain transcriptionally active, ASLV proviruses are prone to rapid silencing. The HIV provirus displays gradual silencing only after an extended time period in culture. The analysis of integration sites of long-term stably expressed proviruses shows a strong bias for some genomic features—especially integration close to the transcription start sites of active transcription units. Furthermore, complex analysis of histone modifications enriched at the site of integration points to the accumulation of proviruses of all three groups in gene regulatory segments, particularly close to the enhancer loci. We conclude that the proximity to active regulatory chromatin segments correlates with stable provirus expression in various retroviral species. PMID:29517993

Temporal Stability of Rotors and Atrial Activation Patterns in Persistent Human Atrial Fibrillation: A High-Density Epicardial Mapping Study of Prolonged Recordings.

PubMed

Walters, Tomos E; Lee, Geoffrey; Morris, Gwilym; Spence, Steven; Larobina, Marco; Atkinson, Victoria; Antippa, Phillip; Goldblatt, John; Royse, Alistair; O'Keefe, Michael; Sanders, Prashanthan; Morton, Joseph B; Kistler, Peter M; Kalman, Jonathan M

This study aimed to determine the spatiotemporal stability of rotors and other atrial activation patterns over 10 min in longstanding, persistent AF, along with the relationship of rotors to short cycle-length (CL) activity. The prevalence, stability, and mechanistic importance of rotors in human atrial fibrillation (AF) remain unclear. Epicardial mapping was performed in 10 patients undergoing cardiac surgery, with bipolar electrograms recorded over 10 min using a triangular plaque (area: 6.75 cm 2 ; 117 bipoles; spacing: 2.5 mm) applied to the left atrial posterior wall (n = 9) and the right atrial free wall (n = 4). Activations were identified throughout 6 discrete 10-s segments of AF spanning 10 min, and dynamic activation mapping was performed. The distributions of 4,557 generated activation patterns within each mapped region were compared between the 6 segments. The dominant activation pattern was the simultaneous presence of multiple narrow wave fronts (26%). Twelve percent of activations represented transient rotors, seen in 85% of mapped regions with a median duration of 3 rotations. A total of 87% were centered on an area of short CL activity (<100 ms), although such activity had a positive predictive value for rotors of only 0.12. The distribution of activation patterns and wave-front directionality were highly stable over time, with a single dominant pattern within a 10-s AF segment recurring across all 6 segments in 62% of mapped regions. In patients with longstanding, persistent AF, activation patterns are spatiotemporally stable over 10 min. Transient rotors can be demonstrated in the majority of mapped regions, are spatiotemporally associated with short CL activity, and, when recurrent, demonstrate anatomical determinism. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Effects of a 2-Year Supervised Exercise Program Upon the Body Composition and Muscular Performance of HIV-Infected Patients

PubMed Central

Paes, Lorena da Silva; Borges, Juliana Pereira; dos Santos, Fernanda Monteiro; de Oliveira, Taciana Pinto; Dupin, Jaciara Gomes; Harris, Elizabeth Assumpção; Farinatti, Paulo

2015-01-01

Background : There is a lack of research investigating long-term effects of exercise training upon the body composition and muscle function in HIV-infected patients (PHIV). The study investigated the influence of a 2-year supervised exercise program on body composition and strength of PHIV under highly active antiretroviral therapy (HAART). Methods : A training program including aerobic, strength and flexibility exercises was performed by 27 PHIV (17 men/ 10 women; age: 48.7±7.0 years; HAART: 150.7±65.3 months) during 1 year and 18 PHIV (10 men/ 8 women; age: 50.6±5.2 years; HAART: 176.6±53.1 months) during 2 years. Body composition and knee isokinetic strength were assessed at baseline and at the end of each year of intervention. Results : Body composition remained stable along the whole experiment vs baseline (1-year - total muscle mass: Δ men=1.1%, P=0.21; Δ women=1.4%, P=0.06; trunk fat: Δ men=-0.1%, P=0.65; Δ women=-1.5%, P=0.45; 2 years - total muscle mass: Δ men=2.7%, P=0.54; Δ women=-1.9%, P=0.71; trunk fat: Δ men=4.4%, P=0.96; Δ women=10.0%, P=0.30). After 1-year, peak torque increased in men (Δ extension=4.2%, P=0.01; Δ flexion=12.2%, P=0.04) and total work reduced in women (Δ extension=-15.4%, P=0.01, Δ flexion=-17.5%, P=0.05). All strength markers remained stable vs baseline after 2 years of intervention (P>0.05). Only men showed significant reduction in the risk of disability due to sarcopenia (P=0.05) after 1 year of intervention, which remained stable after 2 years. Conclusion : Long-term exercise training preserved strength and muscle mass in PHIV under HAART. Exercise programs should be part of HIV therapy to prevent sarcopenia of this population along the years. Trial Registration : ACTRN12610000683033; UTN U1111-1116-4416. PMID:26587076

CD4+CD25highFOXP3+ T regulatory cells as a biomarker of disease activity in systemic lupus erythematosus: a prospective study.

PubMed

Tselios, Konstantinos; Sarantopoulos, Alexandros; Gkougkourelas, Ioannis; Boura, Panagiota

2014-01-01

Several studies have reported low numbers of T regulatory cells (Tregs) in active systemic lupus erythematosus (SLE). However, it is not evident if these cells may be utilised as a biomarker in assessing disease activity. Tregs (CD4+CD25highFOXP3+) were prospectively assessed by flow cytometry in 285 separate blood samples from 100 white Caucasian SLE patients and 20 healthy controls. Patients were divided, according to disease activity (as measured by SLEDAI) into groups A (n=39, samples=94, SLEDAI=0), B (n=33, samples=92, SLEDAI=1-5), C (n=10, samples=53, SLEDAI=6-10) and D (n=18, samples=46, SLEDAI>10). Longitudinal measurements were performed in 131 cases (37 relapses, 44 remissions and 50 cases with stable disease activity) during three years. Statistics were performed by Student's t-test or one-way ANOVA; correlations with Pearson co-efficient, while p<0.05 was considered significant. Tregs were found significantly lower in severely active disease (group D), compared to healthy controls, inactive disease, mild and moderate disease activity (0.57±0.16% vs. 1.49±0.19%, 1.19±0.34% and 1.05±0.36%, 0.72±0.21%, p<0.05, respectively). There was a strongly inverse correlation between Tregs and SLEDAI (r=-0.644, p<0.001). Alterations in disease activity were characterised by inverse alterations in Tregs: relapse (from 1.23±0.44% to 0.64±0.19%, p<0.001, mean change 0.59±0.41%), remission (from 0.65±0.27% to 1.17±0.30%, p<0.001, mean change 0.52±0.35%). In cases with unaltered disease activity, Treg numbers remained stable (from 0.98±0.35% to 1.03±0.34%, p=0.245). Tregs were practically halved during relapse (mean reduction 42.6±22.2%), and doubled during remission (mean increment 113±120.9%). Mean change of Tregs in stable disease was significantly lower (7.3±20.6%, p<0.001). A clinically significant change in SLEDAI (sum of cases with relapse and remission, n=81) was followed by a significant (>20%) inverse change in Tregs in 71/81 cases (sensitivity 87.7%). In 50 cases of stable disease activity, Tregs were significantly changed (>20%) in 13 cases (specificity 74%). Positive predictive value (PPV) was 84.5% and negative predictive value (NPV) was 78.7%. CD4+CD25highFOXP3+ T regulatory cells displayed a strongly inverse correlation to disease activity in the long term. Treg alterations reflected changes in SLEDAI with high sensitivity. These cells may be a reliable biomarker for the assessment of disease activity in SLE by longitudinal measurements.

Ankle instability effects on joint position sense when stepping across the active movement extent discrimination apparatus.

PubMed

Witchalls, Jeremy; Waddington, Gordon; Blanch, Peter; Adams, Roger

2012-01-01

Individuals with and without functional ankle instability have been tested for deficits in lower limb proprioception with varied results. To determine whether a new protocol for testing participants' joint position sense during stepping is reliable and can detect differences between participants with unstable and stable ankles. Descriptive laboratory study. University clinical laboratory. Sample of convenience involving 21 young adult university students and staff. Ankle stability was categorized by score on the Cumberland Ankle Instability Tool; 13 had functional ankle instability, 8 had healthy ankles. Test-retest of ankle joint position sense when stepping onto and across the Active Movement Extent Discrimination Apparatus twice, separated by an interim test, standing still on the apparatus and moving only 1 ankle into inversion. Difference in scores between groups with stable and unstable ankles and between test repeats. Participants with unstable ankles were worse at differentiating between inversion angles underfoot in both testing protocols. On repeated testing with the stepping protocol, performance of the group with unstable ankles was improved (Cohen d = 1.06, P = .006), whereas scores in the stable ankle group did not change in the second test (Cohen d = 0.04, P = .899). Despite this improvement, the unstable group remained worse at differentiating inversion angles on the stepping retest (Cohen d = 0.99, P = .020). The deficits on proprioceptive tests shown by individuals with functional ankle instability improved with repeated exposure to the test situation. The learning effect may be the result of systematic exposure to ankle-angle variation that led to movement-specific learning or increased confidence when stepping across the apparatus.

The Recent Pathology Residency Graduate Job Search Experience: A Synthesis of 5 Years of College of American Pathologists Job Market Surveys.

PubMed

Gratzinger, Dita; Johnson, Kristen A; Brissette, Mark D; Cohen, David; Rojiani, Amyn M; Conran, Richard M; Hoffman, Robert D; Post, Miriam D; McCloskey, Cindy B; Roberts, Cory A; Domen, Ronald E; Talbert, Michael L; Powell, Suzanne Z

2018-04-01

- Pathology residents and fellows tailor their training and job search strategies to an actively evolving specialty in the setting of scientific and technical advances and simultaneous changes in health care economics. - To assess the experience and outcome of the job search process of pathologists searching for their first non-fellowship position. - The College of American Pathologists (CAP) Graduate Medical Education Committee has during the past 5 years sent an annual job search survey each June to CAP junior members and fellows in practice 3 years or less who have actively searched for a non-fellowship position. - Job market indicators including job interviews, job offers, positions accepted, and job satisfaction have remained stable during the 5 years of the survey. Most survey respondents who had applied for at least 1 position had accepted a position at the time of the survey, and most applicants who had accepted a position were satisfied or very satisfied. However, most attested that finding a non-fellowship position was difficult. Despite a perceived push toward subspecialization in surgical pathology, the reported number of fellowships completed was stable. Respondent demographics were not associated with job search success with 1 significant exception: international medical school graduate respondents reported greater perceived difficulty in finding a position, and indeed, fewer reported having accepted a position. - Pathology residents and fellows seeking their first position have faced a relatively stable job market during the last 5 years, with most accepting positions with which they were satisfied.

Arrested Hydrocephalus in Childhood: Case Series and Review of the Literature.

PubMed

Hurni, Yannick; Poretti, Andrea; Schneider, Jacques; Guzman, Raphael; Ramelli, Gian Paolo

2018-06-22

 Hydrocephalus can be progressive or spontaneously arrested. In arrested hydrocephalus, the balance between production and absorption of the cerebrospinal fluid is restored. Patients are mostly asymptomatic, and no surgical treatment is necessary for them.  We performed a two-center consecutive case series study, aimed at investigating the safety of nonsurgical management of hydrocephalus in selected pediatric patients. We retrospectively selected all consecutive patients, suspected to suffer from arrested hydrocephalus and referred to our two institutions between January 2011 and December 2013. Data on clinical and radiological follow-up were collected until June 2017.  Five children diagnosed with arrested hydrocephalus were included in the study. All patients presented macrocephaly as the main presenting sign. Associated mild-to-moderate stable motor disorders were assessed in four out of five cases. Typical symptoms and signs associated with acute raised intracranial pressure were absent in all patients. Magnetic resonance imaging studies showed ventriculomegaly in all patients. A diagnosis of arrested hydrocephalus was made in all five cases based on stable clinical and radiological findings during the initial observation. Conservative management based on active surveillance was, therefore, proposed. During the follow-up period, we observed stable or improved conditions in four out of five patients, while the remaining patient presented progressive hydrocephalus.  Making a distinction between arrested and progressive hydrocephalus is fundamental, because of the opposed appropriate management. Any newly discovered case of hydrocephalus, not characterized by clear signs of progressive hydrocephalus, should benefit from active surveillance before any definitive decision is taken. Georg Thieme Verlag KG Stuttgart · New York.

Climate, Environment and Early Human Innovation: Stable Isotope and Faunal Proxy Evidence from Archaeological Sites (98-59ka) in the Southern Cape, South Africa.

PubMed

Roberts, Patrick; Henshilwood, Christopher S; van Niekerk, Karen L; Keene, Petro; Gledhill, Andrew; Reynard, Jerome; Badenhorst, Shaw; Lee-Thorp, Julia

2016-01-01

The Middle Stone Age (MSA) of southern Africa, and in particular its Still Bay and Howiesons Poort lithic traditions, represents a period of dramatic subsistence, cultural, and technological innovation by our species, Homo sapiens. Climate change has frequently been postulated as a primary driver of the appearance of these innovative behaviours, with researchers invoking either climate instability as a reason for the development of buffering mechanisms, or environmentally stable refugia as providing a stable setting for experimentation. Testing these alternative models has proved intractable, however, as existing regional palaeoclimatic and palaeoenvironmental records remain spatially, stratigraphically, and chronologically disconnected from the archaeological record. Here we report high-resolution records of environmental shifts based on stable carbon and oxygen isotopes in ostrich eggshell (OES) fragments, faunal remains, and shellfish assemblages excavated from two key MSA archaeological sequences, Blombos Cave and Klipdrift Shelter. We compare these records with archaeological material remains in the same strata. The results from both sites, spanning the periods 98-73 ka and 72-59 ka, respectively, show significant changes in vegetation, aridity, rainfall seasonality, and sea temperature in the vicinity of the sites during periods of human occupation. While these changes clearly influenced human subsistence strategies, we find that the remarkable cultural and technological innovations seen in the sites cannot be linked directly to climate shifts. Our results demonstrate the need for scale-appropriate, on-site testing of behavioural-environmental links, rather than broader, regional comparisons.

Cenozoic episodic uplift and kinematic evolution between the Pamir and Southwestern Tien Shan

NASA Astrophysics Data System (ADS)

Liu, Dongliang; Li, Haibing; Sun, Zhiming; Cao, Yong; Wang, Leizhen; Pan, Jiawei; Han, Liang; Ye, Xiaozhou

2017-08-01

The Pamir Salient and Southwestern Tien Shan belong to two different systems, which collided due to the continuous northward drift of the Indian Plate during the Cenozoic, resulting in a shortening of 300 km. The uplift history and kinematic evolution of the Pamir-Southwestern Tien Shan remain unclear. In this study, we chose the 2025 m-thick Pakabulake formation in the East Wuqia section, at the southern-most margin of the Southwestern Tien Shan system, to obtain a high-resolution magnetostratigraphic record spanning 16.61 Ma to 9.78 Ma. Based on its high sedimentation rate, stable ca. E-W paleocurrents and stable magnetic susceptibility values, the nearby Southwestern Tien Shan was inferred to have undergone stable uplift during this period of sedimentation. Combining our results with the previous low-temperature thermochronology, magnetostratigraphy and re-calculated block rotations, we conclude that four episodic uplift events occurred in the Pamir-Southwestern Tien Shan during the Cenozoic, at times of 50-40 Ma, 35-16 Ma, 11-7 Ma and < 5 Ma, and that the first episodic uplift only occurred in the Pamir Salient. In addition, the Pamir Salient underwent a tectonic transformation from entire- to a half-oroclinal bending rotation during the Miocene, caused by activity along the Karakorum Fault and Kashgar-Yecheng Transfer System.

Orbitofrontal Cortex Signals Expected Outcomes with Predictive Codes When Stable Contingencies Promote the Integration of Reward History

PubMed Central

Shapiro, Matthew L.

2017-01-01

Memory can inform goal-directed behavior by linking current opportunities to past outcomes. The orbitofrontal cortex (OFC) may guide value-based responses by integrating the history of stimulus–reward associations into expected outcomes, representations of predicted hedonic value and quality. Alternatively, the OFC may rapidly compute flexible “online” reward predictions by associating stimuli with the latest outcome. OFC neurons develop predictive codes when rats learn to associate arbitrary stimuli with outcomes, but the extent to which predictive coding depends on most recent events and the integrated history of rewards is unclear. To investigate how reward history modulates OFC activity, we recorded OFC ensembles as rats performed spatial discriminations that differed only in the number of rewarded trials between goal reversals. The firing rate of single OFC neurons distinguished identical behaviors guided by different goals. When >20 rewarded trials separated goal switches, OFC ensembles developed stable and anticorrelated population vectors that predicted overall choice accuracy and the goal selected in single trials. When <10 rewarded trials separated goal switches, OFC population vectors decorrelated rapidly after each switch, but did not develop anticorrelated firing patterns or predict choice accuracy. The results show that, whereas OFC signals respond rapidly to contingency changes, they predict choices only when reward history is relatively stable, suggesting that consecutive rewarded episodes are needed for OFC computations that integrate reward history into expected outcomes. SIGNIFICANCE STATEMENT Adapting to changing contingencies and making decisions engages the orbitofrontal cortex (OFC). Previous work shows that OFC function can either improve or impair learning depending on reward stability, suggesting that OFC guides behavior optimally when contingencies apply consistently. The mechanisms that link reward history to OFC computations remain obscure. Here, we examined OFC unit activity as rodents performed tasks controlled by contingencies that varied reward history. When contingencies were stable, OFC neurons signaled past, present, and pending events; when contingencies were unstable, past and present coding persisted, but predictive coding diminished. The results suggest that OFC mechanisms require stable contingencies across consecutive episodes to integrate reward history, represent predicted outcomes, and inform goal-directed choices. PMID:28115481

Clinical and MRI outcomes after stopping or switching disease-modifying therapy in stable MS patients: a case series report.

PubMed

Berkovich, Regina

2017-10-01

To evaluate clinical and MRI outcomes after stopping or switching disease-modifying therapy in patients with stable MS. A retrospective chart review was conducted of stable MS patients who discontinued or switched their DMT from 2011 to 2015. Clinical and MRI outcomes were obtained at baseline and 1-year follow-up. For the DMT discontinuation group, 15 patients were included, with 67% female, 53% Caucasian, mean age of 45.3 ± 12.2 years, disease duration of 9.1 ± 4.3 years, MS type (80% RRMS, 20% SPMS), and EDSS of 3.7 ± 1.6. The average duration of stable MS course was 5.5 ± 3.7 years. Within a mean of 6.4 ± 2.2 months after DMT discontinuation, all 15 patients experienced worsening of MS disease. After re-evaluation of MS treatment options, all 15 patients were restarted on DMT, of which, 6 (40%) restarted on their prior DMT, 4 (26.7%) switched to another DMT due to adverse events on prior DMT, and 5 (33.3%) switched to a more potent DMT due to worsening of MS activity. One year follow-up showed 2 patients (13.3%) who were restarted on their prior DMT experienced a relapse and the remaining 13 patients (86.7%) had no clinical or MRI activities. For the DMT switch group, 23 patients were included, with 65% female, 61% Caucasian, a mean age of 46.9 ± 11.6 years, disease duration of 11.7 ± 5.1 years, MS Type (83% RRMS, 17% SPMS), and EDSS of 3.5 ± 0.9. After switching DMT, 9 (39.1%) patients experienced worsening of clinical or MRI outcomes at the 1-year follow-up. Of the 9 switch failures, the majority (N = 6) were due to switching to dimethyl fumarate. DMT discontinuation in stable MS patients resulted in worsening of MS disease course for all patients, which improved upon DMT restart or switch. In contrast, 39% of MS stable patients experienced worsening of MS disease course when switched to another DMT, with DMT selection potentially impacting switch outcomes. Copyright © 2017 Elsevier B.V. All rights reserved.

Highly cold-active pectinases under wine-like conditions from non-Saccharomyces yeasts for enzymatic production during winemaking.

PubMed

Merín, M G; Morata de Ambrosini, V I

2015-05-01

The influence of oenological factors on cold-active pectinases from 15 preselected indigenous yeasts belonging to Aureobasidium pullulans, Filobasidium capsuligenum, Rhodotorula dairenensis, Cryptococcus saitoi and Saccharomyces cerevisiae was investigated. Pectinolytic enzymes were constitutive or partially constitutive; and high glucose concentration (200 g l(-1) ) did not affect or increased pectinase production at 12°C and pH 3·5 (up to 113·9 U mg(-1) ) only in A. pullulans strains. SO2 (120 mg l(-1) ) slightly affected the growth of A. pullulans strains but did not affect pectinase production levels. Ethanol (15%) barely affected pectinase activity of A. pullulans strains but diminished relative activity to 12-79% of basidiomycetous yeasts. Moreover, non-Saccharomyces strains showed promising properties of oenological interest. This study demonstrates that cold-active pectinases from some A. pullulans strains were able to remain active at glucose, ethanol and SO2 concentrations usually found in vinification, and suggests their potential use as processing aids for low-temperature winemaking. Nowadays, there is increasing interest in low-temperature winemaking. Nevertheless, commercial oenological pectinases, produced by fungi, are rarely active at low temperatures. Cold-active pectinases that are stable under vinification conditions are needed. This study indicated that cold-active and acid-tolerant pectinases from non-Saccharomcyes yeasts were able to remain active at glucose, ethanol and SO2 concentrations usually found in winemaking. Furthermore, not only are these yeasts a source of cold-active pectinases, but the yeasts themselves are also potential adjunct cultures for oenology to produce these enzymes during cold-winemaking. © 2015 The Society for Applied Microbiology.

Complementing in vitro screening assays with in silico ...

EPA Pesticide Factsheets

High-throughput in vitro assays offer a rapid, cost-efficient means to screen thousands of chemicals across hundreds of pathway-based toxicity endpoints. However, one main concern involved with the use of in vitro assays is the erroneous omission of chemicals that are inactive under assay conditions but that can generate active metabolites under in vivo conditions. To address this potential issue, a case study will be presented to demonstrate the use of in silico tools to identify inactive parents with the ability to generate active metabolites. This case study used the results from an orthogonal assay designed to improve confidence in the identification of active chemicals tested across eighteen estrogen receptor (ER)-related in vitro assays by accounting for technological limitations inherent within each individual assay. From the 1,812 chemicals tested within the orthogonal assay, 1,398 were considered inactive. These inactive chemicals were analyzed using Chemaxon Metabolizer software to predict the first and second generation metabolites. From the nearly 1,400 inactive chemicals, over 2,200 first-generation (i.e., primary) metabolites and over 5,500 second-generation (i.e., secondary) metabolites were predicted. Nearly 70% of primary metabolites were immediately detoxified or converted to other metabolites, while over 70% of secondary metabolites remained stable. Among these predicted metabolites, those that are most likely to be produced and remain

Silver coated aluminium microrods as highly colloidal stable SERS platforms.

PubMed

Pazos-Perez, Nicolas; Borke, Tina; Andreeva, Daria V; Alvarez-Puebla, Ramon A

2011-08-01

We report on the fabrication of a novel material with the ability to remain in solution even under the very demanding conditions required for structural and dynamic characterization of biomacromolecule assays. This stability is provided by the increase in surface area of a low density material (aluminium) natively coated with a very hydrophilic surface composed of aluminium oxide (Al(2)O(3)) and metallic silver nanoparticles. Additionally, due to the dense collection of active hot spots on their surface, this material offers higher levels of SERS intensity as compared with the same free and aggregated silver nanoparticles. This journal is © The Royal Society of Chemistry 2011

Anaesthetic Management of Supratentorial Tumor Craniotomy Using Awake-Throughout Approach.

PubMed

Shafiq, Faraz; Salim, Fahad; Enam, Ather; Parkash, Jai; Faheem, Mohammad

2017-12-01

The authors are reporting an anaesthetic management of patient presenting with left parietal lobe space occupying lesion and scheduled for Awake-craniotomy. Awake-throughout approach using scalp block was planned. Among techniques reported for keeping patient awake during the surgery, this one is really underutilized. The successful conduct requires thorough preoperative assessment and psychological preparation. We used powerpoint presentation as a preoperative teaching tool. The anatomical landmark technique was used to institute scalp block, where individual nerves were targeted bilaterally. Patient remained stable throughout and participated actively in intraoperative neurological monitoring. Postoperative period showed remarkable recovery, better pain control, and shorter length of stay in hospital.

The State, Potential Distribution, and Biological Implications of Methane in the Martian Crust

NASA Technical Reports Server (NTRS)

Max, Michael D.; Clifford, Stephen M.

2000-01-01

The search for life on Mars has recently focused on its potential survival in deep (>2 km) subpermafrost aquifers where anaerobic bacteria, similar to those found in deep subsurface ecosystems on Earth, may have survived in an environment that has remained stable for billions of years. An anticipated by-product of this biological activity is methane. The detection of large deposits of methane gas and hydrate in the Martian cryosphere, or as emissions from deep fracture zones, would provide persuasive evidence of indigenous life and confirm the presence of a valuable in situ resource for use by future human explorers.

The Hippocampus Remains Activated over the Long Term for the Retrieval of Truly Episodic Memories

PubMed Central

Harand, Caroline; Bertran, Françoise; La Joie, Renaud; Landeau, Brigitte; Mézenge, Florence; Desgranges, Béatrice; Peigneux, Philippe; Eustache, Francis; Rauchs, Géraldine

2012-01-01

The role of the hippocampus in declarative memory consolidation is a matter of intense debate. We investigated the neural substrates of memory retrieval for recent and remote information using functional magnetic resonance imaging (fMRI). 18 young, healthy participants learned a series of pictures. Then, during two fMRI recognition sessions, 3 days and 3 months later, they had to determine whether they recognized or not each picture using the “Remember/Know” procedure. Presentation of the same learned images at both delays allowed us to track the evolution of memories and distinguish consistently episodic memories from those that were initially episodic and then became familiar or semantic over time and were retrieved without any contextual detail. Hippocampal activation decreased over time for initially episodic, later semantic memories, but remained stable for consistently episodic ones, at least in its posterior part. For both types of memories, neocortical activations were observed at both delays, notably in the ventromedial prefrontal and anterior cingulate cortices. These activations may reflect a gradual reorganization of memory traces within neural networks. Our data indicate maintenance and strengthening of hippocampal and cortico-cortical connections in the consolidation and retrieval of episodic memories over time, in line with the Multiple Trace theory (Nadel and Moscovitch, 1997). At variance, memories becoming semantic over time consolidate through strengthening of cortico-cortical connections and progressive disengagement of the hippocampus. PMID:22937055

Multiple μ-stability of neural networks with unbounded time-varying delays.

PubMed

Wang, Lili; Chen, Tianping

2014-05-01

In this paper, we are concerned with a class of recurrent neural networks with unbounded time-varying delays. Based on the geometrical configuration of activation functions, the phase space R(n) can be divided into several Φη-type subsets. Accordingly, a new set of regions Ωη are proposed, and rigorous mathematical analysis is provided to derive the existence of equilibrium point and its local μ-stability in each Ωη. It concludes that the n-dimensional neural networks can exhibit at least 3(n) equilibrium points and 2(n) of them are μ-stable. Furthermore, due to the compatible property, a set of new conditions are presented to address the dynamics in the remaining 3(n)-2(n) subset regions. As direct applications of these results, we can get some criteria on the multiple exponential stability, multiple power stability, multiple log-stability, multiple log-log-stability and so on. In addition, the approach and results can also be extended to the neural networks with K-level nonlinear activation functions and unbounded time-varying delays, in which there can store (2K+1)(n) equilibrium points, (K+1)(n) of them are locally μ-stable. Numerical examples are given to illustrate the effectiveness of our results. Copyright © 2014 Elsevier Ltd. All rights reserved.

Robust Working Memory in an Asynchronously Spiking Neural Network Realized with Neuromorphic VLSI

PubMed Central

Giulioni, Massimiliano; Camilleri, Patrick; Mattia, Maurizio; Dante, Vittorio; Braun, Jochen; Del Giudice, Paolo

2011-01-01

We demonstrate bistable attractor dynamics in a spiking neural network implemented with neuromorphic VLSI hardware. The on-chip network consists of three interacting populations (two excitatory, one inhibitory) of leaky integrate-and-fire (LIF) neurons. One excitatory population is distinguished by strong synaptic self-excitation, which sustains meta-stable states of “high” and “low”-firing activity. Depending on the overall excitability, transitions to the “high” state may be evoked by external stimulation, or may occur spontaneously due to random activity fluctuations. In the former case, the “high” state retains a “working memory” of a stimulus until well after its release. In the latter case, “high” states remain stable for seconds, three orders of magnitude longer than the largest time-scale implemented in the circuitry. Evoked and spontaneous transitions form a continuum and may exhibit a wide range of latencies, depending on the strength of external stimulation and of recurrent synaptic excitation. In addition, we investigated “corrupted” “high” states comprising neurons of both excitatory populations. Within a “basin of attraction,” the network dynamics “corrects” such states and re-establishes the prototypical “high” state. We conclude that, with effective theoretical guidance, full-fledged attractor dynamics can be realized with comparatively small populations of neuromorphic hardware neurons. PMID:22347151

Stable SET knockdown in breast cell carcinoma inhibits cell migration and invasion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Jie; Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen; Yang, Xi-fei

2014-10-10

Highlights: • We employed RNA interference to knockdown SET expression in breast cancer cells. • Knockdown of SET expression inhibits cell proliferation, migration and invasion. • Knockdown of SET expression increases the activity and expression of PP2A. • Knockdown of SET expression decreases the expression of MMP-9. - Abstract: Breast cancer is the most malignant tumor for women, however, the mechanisms underlying this devastating disease remain unclear. SET is an endogenous inhibitor of protein phosphatase 2A (PP2A) and involved in many physiological and pathological processes. SET could promote the occurrence of tumor through inhibiting PP2A. In this study, we exploremore » the role of SET in the migration and invasion of breast cancer cells MDA-MB-231 and ZR-75-30. The stable suppression of SET expression through lentivirus-mediated RNA interference (RNAi) was shown to inhibit the growth, migration and invasion of breast cancer cells. Knockdown of SET increases the activity and expression of PP2Ac and decrease the expression of matrix metalloproteinase 9 (MMP-9). These data demonstrate that SET may be involved in the pathogenic processes of breast cancer, indicating that SET can serve as a potential therapeutic target for the treatment of breast cancer.« less

Robust Working Memory in an Asynchronously Spiking Neural Network Realized with Neuromorphic VLSI.

PubMed

Giulioni, Massimiliano; Camilleri, Patrick; Mattia, Maurizio; Dante, Vittorio; Braun, Jochen; Del Giudice, Paolo

2011-01-01

We demonstrate bistable attractor dynamics in a spiking neural network implemented with neuromorphic VLSI hardware. The on-chip network consists of three interacting populations (two excitatory, one inhibitory) of leaky integrate-and-fire (LIF) neurons. One excitatory population is distinguished by strong synaptic self-excitation, which sustains meta-stable states of "high" and "low"-firing activity. Depending on the overall excitability, transitions to the "high" state may be evoked by external stimulation, or may occur spontaneously due to random activity fluctuations. In the former case, the "high" state retains a "working memory" of a stimulus until well after its release. In the latter case, "high" states remain stable for seconds, three orders of magnitude longer than the largest time-scale implemented in the circuitry. Evoked and spontaneous transitions form a continuum and may exhibit a wide range of latencies, depending on the strength of external stimulation and of recurrent synaptic excitation. In addition, we investigated "corrupted" "high" states comprising neurons of both excitatory populations. Within a "basin of attraction," the network dynamics "corrects" such states and re-establishes the prototypical "high" state. We conclude that, with effective theoretical guidance, full-fledged attractor dynamics can be realized with comparatively small populations of neuromorphic hardware neurons.

Birefringent Stable Glass with Predominantly Isotropic Molecular Orientation

NASA Astrophysics Data System (ADS)

Liu, Tianyi; Exarhos, Annemarie L.; Alguire, Ethan C.; Gao, Feng; Salami-Ranjbaran, Elmira; Cheng, Kevin; Jia, Tiezheng; Subotnik, Joseph E.; Walsh, Patrick J.; Kikkawa, James M.; Fakhraai, Zahra

2017-09-01

Birefringence in stable glasses produced by physical vapor deposition often implies molecular alignment similar to liquid crystals. As such, it remains unclear whether these glasses share the same energy landscape as liquid-quenched glasses that have been aged for millions of years. Here, we produce stable glasses of 9-(3,5-di(naphthalen-1-yl)phenyl)anthracene molecules that retain three-dimensional shapes and do not preferentially align in a specific direction. Using a combination of angle- and polarization-dependent photoluminescence and ellipsometry experiments, we show that these stable glasses possess a predominantly isotropic molecular orientation while being optically birefringent. The intrinsic birefringence strongly correlates with increased density, showing that molecular ordering is not required to produce stable glasses or optical birefringence, and provides important insights into the process of stable glass formation via surface-mediated equilibration. To our knowledge, such novel amorphous packing has never been reported in the past.

The Changing Lifeworld of Young People: Risk, Resume-Padding, and Civic Engagement. Circle Working Paper 40

ERIC Educational Resources Information Center

Friedland, Lewis A.; Morimoto, Shauna

2005-01-01

This research assumes a relatively stable lifeworld for young people. For example, it assumes that the meaning of volunteering or service is sufficiently similar across multiple contexts to remain a valid and stable indicator. By extension, it also assumes that the lifeworld of young people today is not undergoing a period of rapid, and perhaps…

The Role of Naturally Occurring Stable Isotopes in Mass Spectrometry, Part II: The Instrumentation

PubMed Central

Bluck, Les; Volmer, Dietrich A.

2013-01-01

In the second instalment of this tutorial, the authors explain the instrumentation for measuring naturally occurring stable isotopes, specifically the magnetic sector mass spectrometer. This type of instrument remains unrivalled in its performance for isotope ratio mass spectrometry (IRMS) and the reader is reminded of its operation and its technical advantages for isotope measurements. PMID:23772101

Germ-line transformation of the Queensland fruit fly, Bactrocera tryoni, using a piggyBac vector in the presence of endogenous piggyBac elements

USDA-ARS?s Scientific Manuscript database

We report the stable genetic transformation of the Queensland fruit fly Bactrocera tryoni using a piggyBac vector marked with either the fluorescent protein DsRed or EGFP.A transformation frequency of 5–10% was obtained.Inheritance of the transgenes has remained stable over eight generations despite...

The stable clustering ansatz, consistency relations and gravity dual of large-scale structure

NASA Astrophysics Data System (ADS)

Munshi, Dipak

2018-02-01

Gravitational clustering in the nonlinear regime remains poorly understood. Gravity dual of gravitational clustering has recently been proposed as a means to study the nonlinear regime. The stable clustering ansatz remains a key ingredient to our understanding of gravitational clustering in the highly nonlinear regime. We study certain aspects of violation of the stable clustering ansatz in the gravity dual of Large Scale Structure (LSS). We extend the recent studies of gravitational clustering using AdS gravity dual to take into account possible departure from the stable clustering ansatz and to arbitrary dimensions. Next, we extend the recently introduced consistency relations to arbitrary dimensions. We use the consistency relations to test the commonly used models of gravitational clustering including the halo models and hierarchical ansätze. In particular we establish a tower of consistency relations for the hierarchical amplitudes: Q, Ra, Rb, Sa,Sb,Sc etc. as a functions of the scaled peculiar velocity h. We also study the variants of popular halo models in this context. In contrast to recent claims, none of these models, in their simplest incarnation, seem to satisfy the consistency relations in the soft limit.

Personality stability is associated with better cognitive performance in adulthood: are the stable more able?

PubMed

Graham, Eileen K; Lachman, Margie E

2012-09-01

Although personality is relatively stable over time, there are individual differences in the patterns and magnitude of change. There is some evidence that personality change in adulthood is related to physical health and longevity. The present study expanded this work to consider whether personality stability or change would be associated with better cognitive functioning, especially in later adulthood. A total of 4,974 individuals participated in two waves of The Midlife in the United States Study (MIDUS) in 1994-1995 and 2004-2005. Participants completed the MIDUS personality inventory at both times and the Brief Test of Adult Cognition by Telephone cognitive battery at Time 2. Multiple regression and analysis of covariance analyses showed that, consistent with predictions, individuals remaining stable in openness to experience and neuroticism had faster reaction times and better inductive reasoning than those who changed. Among older adults, those who remained stable or decreased in neuroticism had significantly faster reaction times than those who increased. As predicted, personality stability on some traits was associated with more adaptive cognitive performance on reasoning and reaction time. Personality is discussed as a possible resource for protecting against or minimizing age-related declines in cognition.

Beta-Blockers and Nitrates: Pharmacotherapy and Indications.

PubMed

Facchini, Emanuela; Degiovanni, Anna; Cavallino, Chiara; Lupi, Alessandro; Rognoni, Andrea; Bongo, Angelo S

2015-01-01

Many clinically important differences exist between beta blockers. B1-selectivity is of clinical interest because at clinically used doses, b1- selective agents block cardiac b-receptors while having minor effects on bronchial and vascular b-receptors. Beta-adrenergic blocking agents significantly decrease the frequency and duration of angina pectoris, instead the prognostic benefit of beta-blockers in stable angina has been extrapolated from studies of post myocardial infarction but has not yet been documented without left ventricular disfunction or previous myocardial infarction. Organic nitrates are among the oldest drugs, but they still remain a widely used adjuvant in the treatment of symptomatic coronary artery disease. While their efficacy in relieving angina pectoris symptoms in acute settings and in preventing angina before physical or emotional stress is undisputed, the chronic use of nitrates has been associated with potentially important side effects such as tolerance and endothelial dysfunction. B-blockers are the firstline anti-anginal therapy in stable stable angina patients without contraindications, while nitrates are the secondline anti-anginal therapy. Despite 150 years of clinical practice, they remain fascinating drugs, which in a chronic setting still deserve investigation. This review evaluated pharmacotherapy and indications of Beta-blockers and nitrates in stable angina.

Heat reversal of activity-based anorexia: implications for the treatment of anorexia nervosa.

PubMed

Gutierrez, Emilio; Cerrato, María; Carrera, Olaia; Vazquez, Reyes

2008-11-01

Activity-based anorexia (ABA) provides an animal model of anorexia nervosa (AN). In this model, rats given restricted access to food but unrestricted access to activity wheels, run excessively while reducing food intake, lose a sizeable percentage of body weight, become hypothermic, and can fail to recover unless removed from these conditions. Once rats had lost 20% of body weight under standard ABA conditions, they were assigned to one of two ambient temperature (AT) conditions. Increased AT reduced running rates and led to weight gain in active rats. The effect of increasing AT on food intake was dependent on whether the rats were sedentary or active. Although warming reduced food intake in the sedentary rats their body weight remained stable, whereas in active rats increased AT did not reduce food intake and weight gain gradually rose. From a translational perspective, these findings offer a fresh perspective to the disorder, and underscore the need for further studies to assess the effects of heat treatment in patients as an innovative adjunctive treatment for anorexia nervosa.

Dynamic reorganization of human resting-state networks during visuospatial attention.

PubMed

Spadone, Sara; Della Penna, Stefania; Sestieri, Carlo; Betti, Viviana; Tosoni, Annalisa; Perrucci, Mauro Gianni; Romani, Gian Luca; Corbetta, Maurizio

2015-06-30

Fundamental problems in neuroscience today are understanding how patterns of ongoing spontaneous activity are modified by task performance and whether/how these intrinsic patterns influence task-evoked activation and behavior. We examined these questions by comparing instantaneous functional connectivity (IFC) and directed functional connectivity (DFC) changes in two networks that are strongly correlated and segregated at rest: the visual (VIS) network and the dorsal attention network (DAN). We measured how IFC and DFC during a visuospatial attention task, which requires dynamic selective rerouting of visual information across hemispheres, changed with respect to rest. During the attention task, the two networks remained relatively segregated, and their general pattern of within-network correlation was maintained. However, attention induced a decrease of correlation in the VIS network and an increase of the DAN→VIS IFC and DFC, especially in a top-down direction. In contrast, within the DAN, IFC was not modified by attention, whereas DFC was enhanced. Importantly, IFC modulations were behaviorally relevant. We conclude that a stable backbone of within-network functional connectivity topography remains in place when transitioning between resting wakefulness and attention selection. However, relative decrease of correlation of ongoing "idling" activity in visual cortex and synchronization between frontoparietal and visual cortex were behaviorally relevant, indicating that modulations of resting activity patterns are important for task performance. Higher order resting connectivity in the DAN was relatively unaffected during attention, potentially indicating a role for simultaneous ongoing activity as a "prior" for attention selection.

Radio Disappearance of the Magnetar XTE J1810-197 and Continued X-ray Timing

NASA Astrophysics Data System (ADS)

Camilo, F.; Ransom, S. M.; Halpern, J. P.; Alford, J. A. J.; Cognard, I.; Reynolds, J. E.; Johnston, S.; Sarkissian, J.; van Straten, W.

2016-04-01

We report on timing, flux density, and polarimetric observations of the transient magnetar and 5.54 s radio pulsar XTE J1810-197 using the Green Bank, Nançay, and Parkes radio telescopes beginning in early 2006, until its sudden disappearance as a radio source in late 2008. Repeated observations through 2016 have not detected radio pulsations again. The torque on the neutron star, as inferred from its rotation frequency derivative \\dot{ν }, decreased in an unsteady manner by a factor of three in the first year of radio monitoring, until approximately mid-2007. By contrast, during its final year as a detectable radio source, the torque decreased steadily by only 9%. The period-averaged flux density, after decreasing by a factor of 20 during the first 10 months of radio monitoring, remained relatively steady in the next 22 months, at an average of 0.7 ± 0.3 mJy at 1.4 GHz, while still showing day-to-day fluctuations by factors of a few. There is evidence that during this last phase of radio activity the magnetar had a steep radio spectrum, in contrast to earlier flat-spectrum behavior. No secular decrease presaged its radio demise. During this time, the pulse profile continued to display large variations; polarimetry, including of a new profile component, indicates that the magnetic geometry remained consistent with that of earlier times. We supplement these results with X-ray timing of the pulsar from its outburst in 2003 up to 2014. For the first 4 years, XTE J1810-197 experienced non-monotonic excursions in frequency derivative by at least a factor of eight. But since 2007, its \\dot{ν } has remained relatively stable near its minimum observed value. The only apparent event in the X-ray record that is possibly contemporaneous with the radio shutdown is a decrease of ≈20% in the hot-spot flux in 2008-2009, to a stable, minimum value. However, the permanence of the high-amplitude, thermal X-ray pulse, even after the (unexplained) radio demise, implies continuing magnetar activity.

Management of outpatients in France with stable coronary artery disease. Findings from the prospeCtive observational LongitudinAl RegIstry oF patients with stable coronary arterY disease (CLARIFY) registry.

PubMed

Danchin, Nicolas; Ferrieres, Jean; Guenoun, Maxime; Cattan, Simon; Rushton-Smith, Sophie K; Greenlaw, Nicola; Ferrari, Roberto; Steg, Philippe Gabriel

2014-01-01

Improvements in the treatment of coronary artery disease mean that an increasing number of patients survive acute cardiovascular events and live as outpatients with or without anginal symptoms. To determine the characteristics and management of contemporary outpatients with stable coronary artery disease in Western Europe, and to compare France with the other Western European countries. CLARIFY (prospeCtive observational LongitudinAl RegIstry oF patients with stable coronary arterY disease) is an international, prospective, observational, longitudinal study. Between November 2009 and July 2010, 32,954 adult outpatients with stable coronary artery disease (defined as a history of documented myocardial infarction [of >3 months], prior coronary revascularization, chest pain with myocardial ischaemia, or coronary stenosis of>50% proven by angiography) were enrolled in 45 countries. The demographics and management of CLARIFY patients enrolled in France were compared with those enrolled in other Western European countries (Austria, Belgium, Denmark, Germany, Greece, Ireland, Italy, Netherlands, Portugal, Spain, Switzerland and the UK). Of the 14,726 patients enrolled in Western Europe (mean age 66.2 [10.2] years; 79.6% male), 2432 (16.5%) were from France. The use of aspirin was lower in France than in other Western European countries (74.5% vs. 86.9%, respectively), whereas use of thienopyridines (48.5% vs. 21.7%), oral anticoagulants (12.3% vs. 9.0%) and lipid-lowering drugs (95.8% vs. 92.5%) was higher. Beta-blockers were used in 73% of both groups. Angina was less prevalent in France (6.3% vs. 15.5%) and French patients showed higher levels of physical activity than their counterparts in Western Europe. The management of patients with stable CAD in France appears favourable, with good adherence to guideline-based therapies, but there remains room for improvement in terms of symptom and risk factor control. Copyright © 2014. Published by Elsevier Masson SAS.

Effect of temperature on soluble invertase activity, and glucose, fructose and sucrose status of onion bulbs (Allium cepa) in store.

PubMed

Benkeblia, Noureddine; Onodera, Shuichi; Yoshihira, Taiki; Kosaka, Shinichi; Shiomi, Norio

2004-06-01

The activity of soluble invertase, and the variation in glucose, fructose and sucrose contents in onion bulbs (Allium cepa) during long-term storage at 10 degrees C and 20 degrees C were investigated. Invertase activity increased progressively after 8 weeks to 0.084 and 0.092 nkat/g fresh weight (FW), then sharply to 0.29 and 0.35 nkat/g FW at 20 degrees C and 10 degrees C, respectively, and remained high during 5 weeks. Then, activity decreased abruptly to 0.039 and 0.041 nkat/g, and remained low during the last 8 weeks and close to that observed initially. Glucose increased to 17.73 and 14.62 mg/g FW after 4 weeks at 20 degrees C and 10 degrees C, respectively, then decreased sharply between week 5 and week 7 to 4.13 and 4.91 mg/g FW, respectively, and remained rather stable ranging from 9 and 10 mg/g FW at both temperatures. Fructose showed a similar pattern and was 14.8 and 21.68 mg/g FW at 20 degrees C and 10 degrees C, respectively. Between week 10 and week 24, fructose ranged from 5 and 6 mg/g FW, and from 6 and 7 mg/g FW at 20 degrees C and 10 degrees C, respectively. Sucrose increased to 19.63 and 14.43 mg/g FW at 20 degrees C and 10 degrees C, respectively, decreased during 3 weeks, and then increased randomly from 5.69 to 9.42 mg/g FW at 20 degrees C, but remained in a steady state at 10 degrees C ranging 5.03 +/- 0.78 mg/g FW. During the last 6 weeks, the sucrose content was higher at 20 degrees C than at 10 degrees C. The fructose-glucose ratio varied during the first 8 weeks but remained at a steady level during the last 16 weeks. The (glucose+fructose)/sucrose ratio increased randomly at 10 degrees C, whereas at 20 degrees C the ratio increased during 10 weeks then decreased progressively during the final 14 weeks.

Resolution rate of isolated low-grade hydronephrosis diagnosed within the first year of life

PubMed Central

Madden-Fuentes, Ramiro J.; McNamara, Erin R.; Nseyo, Unwanaobong; Wiener, John S.; Routh, Jonathan C.; Ross, Sherry S.

2015-01-01

Objective Diagnosis of low-grade hydronephrosis often occurs prenatally, during evaluation after urinary tract infection (UTI), or imaging for non-urologic reasons within the first year of life. Its significance in terms of resolution, need for antibiotic prophylaxis, or progression to surgery remains uncertain. We hypothesized that isolated low-grade hydronephrosis in this population frequently resolves, UTIs are infrequent, and progression to surgical intervention is minimal. Patients and methods Children <12 months old diagnosed hydronephrosis (Society for Fetal Urology [SFU] grade 1 or 2) between January 2004 and December 2009 were identified by ICD9 code. Patients with other urological abnormalities were excluded. Stability of hydronephrosis, UTI (≥100,000 CFU/mL bacterial growth) or need for surgical intervention was noted. Results Of 1496 infants with hydronephrosis, 416 (623 renal units) met inclusion criteria. Of 398 renal units with grade 1 hydronephrosis, 385 (96.7%) resolved or remained stable. Only 13 (3.3%) worsened, of which one underwent ureteroneocystostomy. Of 225 renal units with grade 2 hydro-nephrosis, 222 (98.7%) resolved, improved or remained stable, three (1.3%) worsened, of which one required pyeloplasty. Only 0.7% of patients in the ambulatory setting had a febrile UTI. Conclusions Low-grade hydronephrosis diagnosed within the first year of life remains stable or improves in 97.4% of renal units. Given the low rate of recurrent UTI in the ambulatory setting, antibiotic prophylaxis has a limited role in management. PMID:25185821

Resolution rate of isolated low-grade hydronephrosis diagnosed within the first year of life.

PubMed

Madden-Fuentes, Ramiro J; McNamara, Erin R; Nseyo, Unwanaobong; Wiener, John S; Routh, Jonathan C; Ross, Sherry S

2014-08-01

Diagnosis of low-grade hydronephrosis often occurs prenatally, during evaluation after urinary tract infection (UTI), or imaging for non-urologic reasons within the first year of life. Its significance in terms of resolution, need for antibiotic prophylaxis, or progression to surgery remains uncertain. We hypothesized that isolated low-grade hydronephrosis in this population frequently resolves, UTIs are infrequent, and progression to surgical intervention is minimal. Children < 12 months old diagnosed hydronephrosis (Society for Fetal Urology [SFU] grade 1 or 2) between January 2004 and December 2009 were identified by ICD9 code. Patients with other urological abnormalities were excluded. Stability of hydronephrosis, UTI (≥ 100,000 CFU/mL bacterial growth) or need for surgical intervention was noted. Of 1496 infants with hydronephrosis, 416 (623 renal units) met inclusion criteria. Of 398 renal units with grade 1 hydronephrosis, 385 (96.7%) resolved or remained stable. Only 13 (3.3%) worsened, of which one underwent ureteroneocystostomy. Of 225 renal units with grade 2 hydronephrosis, 222 (98.7%) resolved, improved or remained stable, three (1.3%) worsened, of which one required pyeloplasty. Only 0.7% of patients in the ambulatory setting had a febrile UTI. Low-grade hydronephrosis diagnosed within the first year of life remains stable or improves in 97.4% of renal units. Given the low rate of recurrent UTI in the ambulatory setting, antibiotic prophylaxis has a limited role in management. Copyright © 2014. Published by Elsevier Ltd.

Correlations of serum cystatin C and hs-CRP with vascular endothelial cell injury in patients with active systemic lupus erythematosus.

PubMed

Gao, Dong; Shao, Juan; Jin, Waishu; Xia, Xiujuan; Qu, Yan

2018-05-22

To investigate the correlations of serum cystatin C and high-sensitivity C-reactive protein (hs-CRP) with vascular endothelial cell injury in patients with active systemic lupus erythematosus (SLE). A total of 80 patients with SLE treated in our hospital from January 2016 to September 2017 were selected and randomly divided into stable-stage group (n=40) and active-stage group (n=40) using a random number table. The expressions of cystatin C and hs-CRPin stable and active stages were compared, and the inner diameters of brachial artery and levels of vascular endothelial growth factors in stable and active stages were also compared.The correlationsof expressions of cystatin C and hs-CRP in active stage with the inner diameter of brachial artery and vascular endothelial growth factor were analyzed. At the same time, the correlation between vascular endothelial growth factor and inner diameter of brachial artery in active stage was analyzed. The level of cystatin C in active stage was higher than that in stable stage (P<0.05), and the expression level of hs-CRP in active stage was also higher than that in stable stage (P<0.05). The inner diameter of brachial artery in active stage was smaller than that in stable stage (P<0.05), butthe level of vascular endothelial growth factor was higher than that in stable stage (P<0.05). The expressions of cystatin C and hs-CRP were negatively correlated with the inner diameter of brachial artery in active stage (P<0.05). The expressions of cystatin C and hs-CRP were positively correlated with vascular endothelial growth factor in active stage (P<0.05). Moreover, there was a negative correlation between vascular endothelial growth factor and inner diameter of brachial artery in active stage (P<0.05). Levels of cystatin C and hs-CRP are significantly increased in patients with active SLE, and the increase degrees are negatively correlated with the inner diameter of brachial artery under ultrasound, but positively correlated with the level of vascular endothelial growth factor in vivo.

Condylectomy and “surgery first” approach: An expedited treatment for condylar hyperplasia in a patient with facial asymmetry

PubMed Central

López, Diego Fernando; Aristizábal, Juan Fernando; Martínez-Smit, Rosana

2017-01-01

ABSTRACT Condylar Hyperplasia (CH) is a self-limiting pathology condition that produces severe facial deformity at the expense of mandibular asymmetry. In this case report a 15-year-old female patient was diagnosed with Unilateral Condylar Hiperplasia (UCH) by mean of single-photon emission computed tomography (SPECT) and histological study. A high condylectomy in the right condyle was performed to stop the active status of the hyperplasia. A month after condylectomy, orthognathic jaw impaction and asymmetric mandibular setback surgery was performed with the Surgery First Approach (SFA). After 10 days, orthodontic appointments were made every two weeks during 4 months. The active phase of treatment lasted 14 months. Excellent facial and occlusal outcomes were obtained and after 24 months in retention the results remained stable. PMID:28902254

Cloning and expression of L-asparaginase gene in Escherichia coli.

PubMed

Wang, Y; Qian, S; Meng, G; Zhang, S

2001-08-01

The L-asparaginase (ASN) from Escherichia coli AS1.357 was cloned as a DNA fragment generated using polymerase chain reaction technology and primers derived from conserved regions of published ASN gene sequences. Recombinant plasmid pASN containing ASN gene and expression vector pBV220 was transformed in different E. coli host strains. The activity and expression level of ASN in the engineering strains could reach 228 IU/mL of culture fluid and about 50% of the total soluble cell protein respectively, more than 40-fold the enzyme activity of the wild strain. The recombinant plasmid in E. coli AS1.357 remained stable after 72 h of cultivation and 5 h of heat induction without selective pressure. The ASN gene of E. coli AS1.357 was sequenced and had high homology compared to the reported data.

Flashback phenomenon and residual neurological deficits after the use of "bath salt" 3, 4- methylenedioxypyrovalerone.

PubMed

Mangold, Aaron R; Bravo, Thomas P; Traub, Stephen J; Maher, Steven A; Lipinski, Christopher A

2014-01-01

The use and abuse of designer drugs has been recognized for decades; however there are many derivatives of compounds that make their way into the community. Abuse of compound(s) known on the street as "bath salt" is on the rise. We report the case of a 33-year-old man who complained of "flashbacks" and right arm shaking that followed a night of "bath salt" snorting. The active compound methylenedioxypyrovalerone methamphetamine (MDPV) was confirmed; however, analysis of three different "bath salt" products showed difference in their active components. The patient's symptoms remained stable and he was discharged home after observation in the emergency department with instructions to return for any symptom progression. Practitioners should be aware of the abuse of the compounds and that not all "bath salt" products contain MDPV.

Local Helioseismology of Emerging Active Regions: A Case Study

NASA Astrophysics Data System (ADS)

Kosovichev, Alexander G.; Zhao, Junwei; Ilonidis, Stathis

2018-04-01

Local helioseismology provides a unique opportunity to investigate the subsurface structure and dynamics of active regions and their effect on the large-scale flows and global circulation of the Sun. We use measurements of plasma flows in the upper convection zone, provided by the Time-Distance Helioseismology Pipeline developed for analysis of solar oscillation data obtained by Helioseismic and Magnetic Imager (HMI) on Solar Dynamics Observatory (SDO), to investigate the subsurface dynamics of emerging active region NOAA 11726. The active region emergence was detected in deep layers of the convection zone about 12 hours before the first bipolar magnetic structure appeared on the surface, and 2 days before the emergence of most of the magnetic flux. The speed of emergence determined by tracking the flow divergence with depth is about 1.4 km/s, very close to the emergence speed in the deep layers. As the emerging magnetic flux becomes concentrated in sunspots local converging flows are observed beneath the forming sunspots. These flows are most prominent in the depth range 1-3 Mm, and remain converging after the formation process is completed. On the larger scale converging flows around active region appear as a diversion of the zonal shearing flows towards the active region, accompanied by formation of a large-scale vortex structure. This process occurs when a substantial amount of the magnetic flux emerged on the surface, and the converging flow pattern remains stable during the following evolution of the active region. The Carrington synoptic flow maps show that the large-scale subsurface inflows are typical for active regions. In the deeper layers (10-13 Mm) the flows become diverging, and surprisingly strong beneath some active regions. In addition, the synoptic maps reveal a complex evolving pattern of large-scale flows on the scale much larger than supergranulation

Effect of dopamine injection on the hemocyte count and prophenoloxidase system of the white shrimp Litopenaeus vannamei

NASA Astrophysics Data System (ADS)

Pan, Luqing; Hu, Fawen; Zheng, Debin

2011-09-01

Effects of dopamine injection on the hemocyte count, phenoloxidase activity, serine proteinase activity, proteinase inhibitor activity and α2-macroglobulin-like activity in L. vannamei were studied. Results showed that dopamine injection resulted in a significant effect on the parameters measured ( P < 0.05), while no significant difference was observed in the control group (0.85% NaCl). In the experimental groups, the hemocyte count reached the minimum in 3 h; granular and semi-granular cells became stable after 12 h and hyaline cells and the total hemocyte count became stable after 18 h. Phenoloxidase activity reached the minimum in 6 h, and then became stable after 9 h. Serine protease activity and proteinase inhibitor activity reached the minimum in 3 h, and α2-macroglobulin-like activity reached the maximum in 3 h, and all the three parameters became stable after 12 h. The results suggest that the activating mechanisms of the proPO system triggered by dopamine are different from those triggered by invasive agents or spontaneously activated under a normal physical condition.

Climate, Environment and Early Human Innovation: Stable Isotope and Faunal Proxy Evidence from Archaeological Sites (98-59ka) in the Southern Cape, South Africa

PubMed Central

Keene, Petro; Gledhill, Andrew; Reynard, Jerome; Badenhorst, Shaw

2016-01-01

The Middle Stone Age (MSA) of southern Africa, and in particular its Still Bay and Howiesons Poort lithic traditions, represents a period of dramatic subsistence, cultural, and technological innovation by our species, Homo sapiens. Climate change has frequently been postulated as a primary driver of the appearance of these innovative behaviours, with researchers invoking either climate instability as a reason for the development of buffering mechanisms, or environmentally stable refugia as providing a stable setting for experimentation. Testing these alternative models has proved intractable, however, as existing regional palaeoclimatic and palaeoenvironmental records remain spatially, stratigraphically, and chronologically disconnected from the archaeological record. Here we report high-resolution records of environmental shifts based on stable carbon and oxygen isotopes in ostrich eggshell (OES) fragments, faunal remains, and shellfish assemblages excavated from two key MSA archaeological sequences, Blombos Cave and Klipdrift Shelter. We compare these records with archaeological material remains in the same strata. The results from both sites, spanning the periods 98–73 ka and 72–59 ka, respectively, show significant changes in vegetation, aridity, rainfall seasonality, and sea temperature in the vicinity of the sites during periods of human occupation. While these changes clearly influenced human subsistence strategies, we find that the remarkable cultural and technological innovations seen in the sites cannot be linked directly to climate shifts. Our results demonstrate the need for scale-appropriate, on-site testing of behavioural-environmental links, rather than broader, regional comparisons. PMID:27383620

Long-Term Stability of Motor Cortical Activity: Implications for Brain Machine Interfaces and Optimal Feedback Control.

PubMed

Flint, Robert D; Scheid, Michael R; Wright, Zachary A; Solla, Sara A; Slutzky, Marc W

2016-03-23

The human motor system is capable of remarkably precise control of movements--consider the skill of professional baseball pitchers or surgeons. This precise control relies upon stable representations of movements in the brain. Here, we investigated the stability of cortical activity at multiple spatial and temporal scales by recording local field potentials (LFPs) and action potentials (multiunit spikes, MSPs) while two monkeys controlled a cursor either with their hand or directly from the brain using a brain-machine interface. LFPs and some MSPs were remarkably stable over time periods ranging from 3 d to over 3 years; overall, LFPs were significantly more stable than spikes. We then assessed whether the stability of all neural activity, or just a subset of activity, was necessary to achieve stable behavior. We showed that projections of neural activity into the subspace relevant to the task (the "task-relevant space") were significantly more stable than were projections into the task-irrelevant (or "task-null") space. This provides cortical evidence in support of the minimum intervention principle, which proposes that optimal feedback control (OFC) allows the brain to tightly control only activity in the task-relevant space while allowing activity in the task-irrelevant space to vary substantially from trial to trial. We found that the brain appears capable of maintaining stable movement representations for extremely long periods of time, particularly so for neural activity in the task-relevant space, which agrees with OFC predictions. It is unknown whether cortical signals are stable for more than a few weeks. Here, we demonstrate that motor cortical signals can exhibit high stability over several years. This result is particularly important to brain-machine interfaces because it could enable stable performance with infrequent recalibration. Although we can maintain movement accuracy over time, movement components that are unrelated to the goals of a task (such as elbow position during reaching) often vary from trial to trial. This is consistent with the minimum intervention principle of optimal feedback control. We provide evidence that the motor cortex acts according to this principle: cortical activity is more stable in the task-relevant space and more variable in the task-irrelevant space. Copyright © 2016 the authors 0270-6474/16/363623-10$15.00/0.

Cellulose binding domain assisted immobilization of lipase (GSlip-CBD) onto cellulosic nanogel: characterization and application in organic medium.

PubMed

Kumar, Ashok; Zhang, Shaowei; Wu, Gaobing; Wu, Cheng Chao; Chen, JunPeng; Baskaran, R; Liu, Ziduo

2015-12-01

A cbd gene was cloned into the C-terminal region of a lip gene from Geobacillus stearothermophilus. The native lipase (43.5 kDa) and CBD-Lip fusion protein (60.2 kDa) were purified to homogeneity by SDS-PAGE. A highly stable cellulosic nanogel was prepared by controlled hydrolysis of microcrystalline cellulose onto which the CBD-lip fusion protein was immobilized through bio-affinity based binding. The nanogel-bound lipase showed optimum activity at 55 °C, and it remains stable and active at pH 10-10.5. Furthermore, the immobilized lipase showed an over two-fold increase of relative activity in the presence of DMSO, isopropanol, isoamyl alcohol and n-butanol, but a mild activity decrease at a low concentration of methanol and ethanol. The immobilized biocatalyst retained ~50% activity after eight repetitive hydrolytic cycles. Enzyme kinetic studies of the immobilized lipase showed a 1.24 fold increase in Vmax and 5.25 fold increase in kcat towards p-NPP hydrolysis. Additionally, the nanogel bound lipase was tested to synthesize a biodiesel ester, ethyl oleate in DMSO. Kinetic analysis showed the km 100.5 ± 4.3 mmol and Vmax 0.19 ± 0.015 mmolmin(-1) at varied oleic acid concentration. Also, the values of km and Vmax at varying concentration of ethanol were observed to be 95.9 ± 13.9 mmol and 0.22 ± 0.013 mmolmin(-1) respectively. The maximum yield of ethyl oleate 111.2 ± 1.24 mM was obtained under optimized reaction conditions in organic medium. These results suggest that this immobilized biocatalyst can be used as an efficient tool for the biotransformation reactions on an industrial scale. Copyright © 2015 Elsevier B.V. All rights reserved.

Heat tolerance in a wild Oryza species is attributed to maintenance of Rubisco activation by a thermally stable Rubisco activase ortholog.

PubMed

Scafaro, Andrew P; Gallé, Alexander; Van Rie, Jeroen; Carmo-Silva, Elizabete; Salvucci, Michael E; Atwell, Brian J

2016-08-01

The mechanistic basis of tolerance to heat stress was investigated in Oryza sativa and two wild rice species, Oryza meridionalis and Oryza australiensis. The wild relatives are endemic to the hot, arid Australian savannah. Leaf elongation rates and gas exchange were measured during short periods of supra-optimal heat, revealing species differences. The Rubisco activase (RCA) gene from each species was sequenced. Using expressed recombinant RCA and leaf-extracted RCA, the kinetic properties of the two isoforms were studied under high temperatures. Leaf elongation was undiminished at 45°C in O. australiensis. The net photosynthetic rate was almost 50% slower in O. sativa at 45°C than at 28°C, while in O. australiensis it was unaffected. Oryza meridionalis exhibited intermediate heat tolerance. Based on previous reports that RCA is heat-labile, the Rubisco activation state was measured. It correlated positively with leaf elongation rates across all three species and four periods of exposure to 45°C. Sequence analysis revealed numerous polymorphisms in the RCA amino acid sequence from O. australiensis. The O. australiensis RCA enzyme was thermally stable up to 42°C, contrasting with RCA from O. sativa, which was inhibited at 36°C. We attribute heat tolerance in the wild species to thermal stability of RCA, enabling Rubisco to remain active. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

The Education Review Board: A Mechanism for Managing Potential Conflicts of Interest in Medical Education.

PubMed

Borus, Jonathan F; Alexander, Erik K; Bierer, Barbara E; Bringhurst, F Richard; Clark, Christopher; Klanica, Kaley E; Stewart, Erin C; Friedman, Lawrence S

2015-12-01

Concerns about the influence of industry support on medical education, research, and patient care have increased in both medical and political circles. Some academic medical centers, questioning whether industry support of medical education could be appropriate and not a conflict of interest, banned such support. In 2009, a Partners HealthCare System commission concluded that interactions with industry remained important to Partners' charitable academic mission and made recommendations to transparently manage such relationships. An Education Review Board (ERB) was created to oversee and manage all industry support of Partners educational activities.Using a case review method, the ERB developed guidelines to implement the commission's recommendations. A multi-funder rule was established that prohibits industry support from only one company for any Partners educational activity. Within that framework, the ERB established guidelines on industry support of educational conferences, clinical fellowships, and trainees' expenses for attending external educational programs; gifts of textbooks and other educational materials; promotional opportunities associated with Partners educational activities; Partners educational activities under contract with an industry entity; and industry-run programs using Partners resources.Although many changes have resulted from the implementation of the ERB guidelines, the number of industry grants for Partners educational activities has remained relatively stable, and funding for these activities declined only moderately during the first three full calendar years (2011-2013) of ERB oversight. The ERB continually educates both the Partners community and industry about the rationale for its guidelines and its openness to their refinement in response to changes in the external environment.

Formation of multimeric antibodies for self-delivery of active monomers.

PubMed

Dekel, Yaron; Machluf, Yossy; Gefen, Tal; Eidelshtein, Gennady; Kotlyar, Alexander; Bram, Yaron; Shahar, Ehud; Reslane, Farah; Aizenshtein, Elina; Pitcovski, Jacob

2017-11-01

Proteins and peptides have been used as drugs for almost a century. Technological advances in the past 30 years have enabled the production of pure, stable proteins in vast amounts. In contrast, administration of proteins based on their native active conformation (and thus necessitating the use of subcutaneous injections) has remained solely unchanged. The therapeutic anti-HER2 humanized monoclonal immunoglobulin (IgG) Trastuzumab (Herceptin) is a first line of the treatment for breast cancer. Chicken IgY is a commercially important polyclonal antibody (Ab). These Abs were examined for their ability to self-assemble and form ordered aggregates, by several biophysical methods. Atomic force microscopy analyses revealed the formation of multimeric nanostructures. The biological activity of multimeric IgG or IgY particles was retained and restored, in a dilution/time-dependent manner. IgG activity was confirmed by a binding assay using HER2 + human breast cancer cell line, SKBR3, while IgY activity was confirmed by ELISA assay using the VP2 antigen. Competition assay with native Herceptin antibodies demonstrated that the binding availability of the multimer formulation remained unaffected. Under long incubation periods, IgG multimers retained five times more activity than native IgG. In conclusion, the multimeric antibody formulations can serve as a storage depositories and sustained-release particles. These two important characteristics make this formulation promising for future novel administration protocols and altogether bring to light a different conceptual approach for the future use of therapeutic proteins as self-delivery entities rather than conjugated/encapsulated to other bio-compounds.

Across the Great Divide

ERIC Educational Resources Information Center

Nelson, Cary

2008-01-01

There are two worlds that exist in the academe: a world where the tenure system remains strong and a world dominated by the absence of tenure. In this article, the author cites the differences between these two worlds. In a world where tenure remains strong, academic departments benefit from a stable, dedicated workforce composed of tenured and…

Stability of pyrimethamine in a liquid dosage formulation stored for three months.

PubMed

Nahata, M C; Morosco, R S; Hipple, T F

1997-12-01

The stability of pyrimethamine in a liquid dosage formulation stored for up to three months was studies. Commercially available 25-mg pyrimethamine tablets were crushed with a mortar and pestle and mixed with a 1:1 mixture of Simple Syrup, NF, and 1% methylcellulose to yield a suspension with a pyrimethamine concentration of 2 mg/mL. The suspension was poured into 10 amber plastic and 10 amber glass prescription bottles; 5 plastic and 5 glass bottles were stored at 4 degrees C, and the remaining bottles were kept at 25 degrees C. Samples were collected at intervals up to 91 days and tested for pyrimethamine concentration by stability-indicating high-performance liquid chromatography. Pyrimethamine remained stable throughout the three-month study period under all conditions. At 4 degrees C, pyrimethamine concentrations remained above 96% of the initial concentration; at 25 degrees C, pyrimethamine concentrations remained above 91%. No substantial changes in pH were observed. Pyrimethamine was stable for at least 91 days in an oral suspension stored in plastic or glass prescription bottles at 4 or 25 degrees C.

Synthesis and biological evaluation of novel 10-substituted-7-ethyl-10-hydroxycamptothecin (SN-38) prodrugs.

PubMed

Zhou, Mo; Liu, Meixia; He, Xinhua; Yu, Hong; Wu, Di; Yao, Yishan; Fan, Shiyong; Zhang, Ping; Shi, Weiguo; Zhong, Bohua

2014-11-27

In an attempt to improve the antitumor activity and reduce the side effects of irinotecan (2), novel prodrugs of SN-38 (3) were prepared by conjugating amino acids or dipeptides to the 10-hydroxyl group of SN-38 via a carbamate linkage. The synthesized compounds completely generated SN-38 in pH 7.4 buffer or in human plasma, while remaining stable under acidic conditions. All prodrug compounds demonstrated much greater in vitro antitumor activities against HeLa cells and SGC-7901 cells than irinotecan. The most active compounds, 5h, 7c, 7d, and 7f, exhibited IC50 values that were 1000 times lower against HeLa cells and 30 times lower against SGC-7901 cells than those of irinotecan, and the inhibitory activities of these prodrugs against acetylcholinesterase (AchE) were significantly reduced, with IC50 values more than 6.8 times greater than that of irinotecan. In addition, compound 5e exhibited the same level of tumor growth inhibitory activity as irinotecan (CPT-11) in a human colon xenograft model in vivo.

Characterization and potential use of cuttlefish skin gelatin hydrolysates prepared by different microbial proteases.

PubMed

Jridi, Mourad; Lassoued, Imen; Nasri, Rim; Ayadi, Mohamed Ali; Nasri, Moncef; Souissi, Nabil

2014-01-01

Composition, functional properties, and in vitro antioxidant activities of gelatin hydrolysates prepared from cuttlefish skin were investigated. Cuttlefish skin gelatin hydrolysates (CSGHs) were obtained by treatment with crude enzyme preparations from Bacillus licheniformis NH1, Bacillus mojavensis A21, Bacillus subtilis A26, and commercial alcalase. All CSGHs had high protein contents, 74.3-78.3%, and showed excellent solubility (over 90%). CSGH obtained by alcalase demonstrated high antioxidant activities monitored by β-carotene bleaching, DPPH radical scavenging, lipid peroxidation inhibition, and reducing power activity. Its antioxidant activity remained stable or increased in a wide range of pH (1-9), during heating treatment (100°C for 240 min) and after gastrointestinal digestion simulation. In addition, alcalase-CSGH was incorporated into turkey meat sausage to determine its effect on lipid oxidation during 35 days of storage period. At 0.5 mg/g, alcalase-CSGH delayed lipid oxidation monitored by TBARS and conjugated diene up to 10 days compared to vitamin C. The results reveal that CSGHs could be used as food additives possessing both antioxidant activity and functional properties.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eric S. Peterson; Jessica Trudeau; Bill Cleary

An active-surface membrane technology was used to separate a die lube manufacturing wastewater stream consisting of various oils, hydrocarbons, heavy metals, and silicones. The ultrafiltration membranes reduced organics from initial oil and grease contents by 20–25X, carbon oxygen demand (COD) by 1.5 to 2X, and total organic carbon (TOC) by 0.6, while the biological oxygen demand (BOD) remained constant. The active-surface membranes were not fouled as badly as non-active-surface systems and the active-surface membrane flux levels were consistently higher and more stable than those of the non-active-surface membranes tested. Field testing demonstrated that the rotary microfilter can concentrate the diemore » lube, i.e. remove the glycerin component, and produce a die lube suitable for recycling. The recycling system operated for six weeks with only seven cleaning cycles and no mechanical or electrical failures. Test data and quality records indicate that the die casting scrap was reduced from 8.4 to 7.8%. There is no doubt that this test yielded tremendous results. This separation process presents significant opportunities that can be evaluated further.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peterson, E. S.; Trudeau, J.; Cleary, B.

An active-surface membrane technology was used to separate a die lube manufacturing wastewater stream consisting of various oils, hydrocarbons, heavy metals, and silicones. The ultrafiltration membranes reduced organics from initial oil and grease contents by 20-25X, carbon oxygen demand (COD) by 1.5 to 2X, and total organic carbon (TOC) by 0.6, while the biological oxygen demand (BOD) remained constant. The active-surface membranes were not fouled as badly as non-active-surface systems and the active-surface membrane flux levels were consistently higher and more stable than those of the non-active-surface membranes tested. Field testing demonstrated that the rotary microfilter can concentrate the diemore » lube, i.e. remove the glycerin component, and produce a die lube suitable for recycling. The recycling system operated for six weeks with only seven cleaning cycles and no mechanical or electrical failures. Test data and quality records indicate that the die casting scrap was reduced from 8.4 to 7.8%. There is no doubt that this test yielded tremendous results. This separation process presents significant opportunities that can be evaluated further.« less

Stability of antimicrobial activity of peracetic acid solutions used in the final disinfection process.

PubMed

Costa, Solange Alves da Silva; Paula, Olívia Ferreira Pereira de; Silva, Célia Regina Gonçalves E; Leão, Mariella Vieira Pereira; Santos, Silvana Soléo Ferreira dos

2015-01-01

The instruments and materials used in health establishments are frequently exposed to microorganism contamination, and chemical products are used before sterilization to reduce occupational infection. We evaluated the antimicrobial effectiveness, physical stability, and corrosiveness of two commercial formulations of peracetic acid on experimentally contaminated specimens. Stainless steel specimens were contaminated with Staphylococcus aureus, Escherichia coli, Candida albicans, blood, and saliva and then immersed in a ready peracetic acid solution: 2% Sekusept Aktiv (SA) or 0.25% Proxitane Alpha (PA), for different times. Then, washes of these instruments were plated in culture medium and colony-forming units counted. This procedure was repeated six times per day over 24 non-consecutive days. The corrosion capacity was assessed with the mass loss test, and the concentration of peracetic acid and pH of the solutions were measured with indicator tapes. Both SA and PA significantly eliminated microorganisms; however, the SA solution was stable for only 4 days, whereas PA remained stable throughout the experiment. The concentration of peracetic acid in the SA solutions decreased over time until the chemical was undetectable, although the pH remained at 5. The PA solution had a concentration of 500-400 mg/L and a pH of 2-3. Neither formulation induced corrosion and both reduced the number of microorganisms (p = 0.0001). However, the differences observed in the performance of each product highlight the necessity of establishing a protocol for optimizing the use of each one.

Timing and causes of mid-Holocene mammoth extinction on St. Paul Island, Alaska

PubMed Central

Graham, Russell W.; Belmecheri, Soumaya; Choy, Kyungcheol; Culleton, Brendan J.; Davies, Lauren J.; Hritz, Carrie; Kapp, Joshua D.; Newsom, Lee A.; Rawcliffe, Ruth; Saulnier-Talbot, Émilie; Wang, Yue; Williams, John W.; Wooller, Matthew J.

2016-01-01

Relict woolly mammoth (Mammuthus primigenius) populations survived on several small Beringian islands for thousands of years after mainland populations went extinct. Here we present multiproxy paleoenvironmental records to investigate the timing, causes, and consequences of mammoth disappearance from St. Paul Island, Alaska. Five independent indicators of extinction show that mammoths survived on St. Paul until 5,600 ± 100 y ago. Vegetation composition remained stable during the extinction window, and there is no evidence of human presence on the island before 1787 CE, suggesting that these factors were not extinction drivers. Instead, the extinction coincided with declining freshwater resources and drier climates between 7,850 and 5,600 y ago, as inferred from sedimentary magnetic susceptibility, oxygen isotopes, and diatom and cladoceran assemblages in a sediment core from a freshwater lake on the island, and stable nitrogen isotopes from mammoth remains. Contrary to other extinction models for the St. Paul mammoth population, this evidence indicates that this mammoth population died out because of the synergistic effects of shrinking island area and freshwater scarcity caused by rising sea levels and regional climate change. Degradation of water quality by intensified mammoth activity around the lake likely exacerbated the situation. The St. Paul mammoth demise is now one of the best-dated prehistoric extinctions, highlighting freshwater limitation as an overlooked extinction driver and underscoring the vulnerability of small island populations to environmental change, even in the absence of human influence. PMID:27482085

Catalyst Architecture for Stable Single Atom Dispersion Enables Site-Specific Spectroscopic and Reactivity Measurements of CO Adsorbed to Pt Atoms, Oxidized Pt Clusters, and Metallic Pt Clusters on TiO2.

PubMed

DeRita, Leo; Dai, Sheng; Lopez-Zepeda, Kimberly; Pham, Nicholas; Graham, George W; Pan, Xiaoqing; Christopher, Phillip

2017-10-11

Oxide-supported precious metal nanoparticles are widely used industrial catalysts. Due to expense and rarity, developing synthetic protocols that reduce precious metal nanoparticle size and stabilize dispersed species is essential. Supported atomically dispersed, single precious metal atoms represent the most efficient metal utilization geometry, although debate regarding the catalytic activity of supported single precious atom species has arisen from difficulty in synthesizing homogeneous and stable single atom dispersions, and a lack of site-specific characterization approaches. We propose a catalyst architecture and characterization approach to overcome these limitations, by depositing ∼1 precious metal atom per support particle and characterizing structures by correlating scanning transmission electron microscopy imaging and CO probe molecule infrared spectroscopy. This is demonstrated for Pt supported on anatase TiO 2 . In these structures, isolated Pt atoms, Pt iso , remain stable through various conditions, and spectroscopic evidence suggests Pt iso species exist in homogeneous local environments. Comparing Pt iso to ∼1 nm preoxidized (Pt ox ) and prereduced (Pt metal ) Pt clusters on TiO 2 , we identify unique spectroscopic signatures of CO bound to each site and find CO adsorption energy is ordered: Pt iso ≪ Pt metal < Pt ox . Pt iso species exhibited a 2-fold greater turnover frequency for CO oxidation than 1 nm Pt metal clusters but share an identical reaction mechanism. We propose the active catalytic sites are cationic interfacial Pt atoms bonded to TiO 2 and that Pt iso exhibits optimal reactivity because every atom is exposed for catalysis and forms an interfacial site with TiO 2 . This approach should be generally useful for studying the behavior of supported precious metal atoms.

The relationship between social functioning and subjective memory complaints in older persons: a population-based longitudinal cohort study.

PubMed

Kuiper, Jisca S; Oude Voshaar, Richard C; Zuidema, Sytse U; Stolk, Ronald P; Zuidersma, Marij; Smidt, Nynke

2017-10-01

Poor social functioning is associated with cognitive decline in older adults. It is unclear whether social functioning is also associated with subjective memory complaints (SMC). We investigated the association between social functioning and incident SMC and SMC recovery. A population-based sample of 8762 older adults (aged ≥65 years) with good objective cognitive functioning at baseline (MMSE ≥26) from the LifeLines Cohort Study were followed for 1.5 years. Self-reported SMC were measured at baseline and after 1.5 years follow-up. Aspects of social functioning included marital status, household composition, social network size, social activity, quality of social relationships, social support, affection, behavioral confirmation, and status. Thirteen percent (513/3963) developed SMC during follow-up (incident SMC). Multivariate logistic regression analyses (adjusted for age, gender, education level, physical activity, alcohol use, smoking status, depression, arrhythmia, myocardial infarction, heart failure, stroke) showed that participants with better feelings of affection, behavioral confirmation and stable good social support had a lower risk of incident SMC. Thirty-four percent (1632/4799) reported recovery. Participants with good social functioning at baseline on all determinants reported more SMC recovery. People who remained stable in a relationship, stable in good quality of social relationships or increased in quality of social relationships more often report SMC recovery. Good social functioning is associated with less incident SMC and more SMC recovery over a follow-up period of 1.5 years. Albeit future confirmative studies are needed, we argue for targeting also social functioning when designing multidomain interventions to prevent or slow down cognitive decline. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Control of External Kink Instability

NASA Astrophysics Data System (ADS)

Navratil, Gerald

2004-11-01

A fundamental pressure and current limiting phenomenon in magnetically confined plasmas for fusion energy is the long wavelength ideal-MHD kink mode. These modes have been extensively studied in tokamak and reversed field pinch (RFP) devices. They are characterized by significant amplitude on the boundary of the confined plasma and can therefore be controlled by manipulation of the external boundary conditions. In the past ten years, the theoretically predicted stabilizing effect of a nearby conducting wall has been documented in experiments, which opens the possibility of a significant increase in maximum stable plasma pressure. While these modes are predicted to remain unstable when the stabilizing wall is resistive, their growth rates are greatly reduced from the hydrodynamic time scale to the time scale of magnetic diffusion through the resistive wall. These resistive wall slowed kink modes have been identified as limiting phenomena in tokamak (DIII-D, PBX-M, HBT-EP, JT-60U, JET, NSTX) and RFP (HBTX, Extrap, T2R) devices. The theoretical prediction of stabilization to nearly the ideal wall pressure limit by toroidal plasma rotation and/or active feedback control using coils has recently been realized experimentally. Sustained, stable operation at double the no-wall pressure limit has been achieved. Discovery of the phenomenon of resonant field amplification by marginally stable kink modes and its role in the momentum balance of rotationally stabilized plasmas has emerged as a key feature. A theoretical framework, based on an extension of the very successful treatment of the n=0 axisymmetric mode developed in the early 1990's, to understand the stabilization mechanisms and model the performance of active feedback control systems is now established. This allows design of kink control systems for burning plasma experiments like ITER.

Ankle Instability Effects on Joint Position Sense When Stepping Across the Active Movement Extent Discrimination Apparatus

PubMed Central

Witchalls, Jeremy; Waddington, Gordon; Blanch, Peter; Adams, Roger

2012-01-01

Context Individuals with and without functional ankle instability have been tested for deficits in lower limb proprioception with varied results. Objective To determine whether a new protocol for testing participants' joint position sense during stepping is reliable and can detect differences between participants with unstable and stable ankles. Design Descriptive laboratory study. Setting University clinical laboratory. Patients or Other Participants Sample of convenience involving 21 young adult university students and staff. Ankle stability was categorized by score on the Cumberland Ankle Instability Tool; 13 had functional ankle instability, 8 had healthy ankles. Intervention(s) Test-retest of ankle joint position sense when stepping onto and across the Active Movement Extent Discrimination Apparatus twice, separated by an interim test, standing still on the apparatus and moving only 1 ankle into inversion. Main Outcome Measure(s) Difference in scores between groups with stable and unstable ankles and between test repeats. Results Participants with unstable ankles were worse at differentiating between inversion angles underfoot in both testing protocols. On repeated testing with the stepping protocol, performance of the group with unstable ankles was improved (Cohen d = 1.06, P = .006), whereas scores in the stable ankle group did not change in the second test (Cohen d = 0.04, P = .899). Despite this improvement, the unstable group remained worse at differentiating inversion angles on the stepping retest (Cohen d = 0.99, P = .020). Conclusions The deficits on proprioceptive tests shown by individuals with functional ankle instability improved with repeated exposure to the test situation. The learning effect may be the result of systematic exposure to ankle-angle variation that led to movement-specific learning or increased confidence when stepping across the apparatus. PMID:23182010

Prognostic value of B-Type natriuretic peptides in patients with stable coronary artery disease: the PEACE Trial.

PubMed

Omland, Torbjørn; Sabatine, Marc S; Jablonski, Kathleen A; Rice, Madeline Murguia; Hsia, Judith; Wergeland, Ragnhild; Landaas, Sverre; Rouleau, Jean L; Domanski, Michael J; Hall, Christian; Pfeffer, Marc A; Braunwald, Eugene

2007-07-17

The purpose of this study was to assess the association between B-type natriuretic peptide (BNP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) and the incidence of specific cardiovascular events in low-risk patients with stable coronary disease, the incremental prognostic information obtained from these two biomarkers compared with traditional risk factors, and their ability to identify patients who may benefit from angiotensin-converting enzyme (ACE) inhibition. The prognostic value of BNPs in low-risk patients with stable coronary artery disease remains unclear. Baseline plasma BNP and NT-proBNP concentrations were measured in 3,761 patients with stable coronary artery disease and preserved left ventricular function participating in the PEACE (Prevention of Events With Angiotensin-Converting Enzyme Inhibition) study, a placebo-controlled trial of trandolapril. Multivariable Cox regression was used to assess the association between natriuretic peptide concentrations and the incidence of cardiovascular mortality, fatal or nonfatal myocardial infarction, heart failure, and stroke. The BNP and NT-proBNP levels were strongly related to the incidence of cardiovascular mortality, heart failure, and stroke but not to myocardial infarction. In multivariable models, BNP remained associated with increased risk of heart failure, whereas NT-proBNP remained associated with increased risk of cardiovascular mortality, heart failure, and stroke. By C-statistic calculations, BNP and NT-proBNP significantly improved the predictive accuracy of the best available model for incident heart failure, and NT-proBNP also improved the model for cardiovascular death. The magnitude of effect of ACE inhibition on the likelihood of experiencing cardiovascular end points was similar, regardless of either BNP or NT-proBNP baseline concentrations. In low-risk patients with stable coronary artery disease and preserved ventricular function, BNPs provide strong and incremental prognostic information to traditional risk factors.

Effect of a stable prostacyclin analogue on canine renal allograft rejection.

PubMed Central

Tobimatsu, M; Ueda, Y; Toyoda, K; Saito, S; Konomi, K

1987-01-01

The effect of OP-41483 (Ono Pharmaceutical Co., Osaka, Japan), a stable prostacyclin analogue, on canine renal allograft rejection was investigated. Administration for 4 days after transplantation significantly increased renal cortical blood flow and urine output when compared with untreated dogs with renal allografts. Serum creatinine levels remained relatively low during postoperative days 1-4. Mean animal survival time was prolonged. Vascular lesions and mononuclear cell infiltration were greatly diminished in biopsy specimens removed on day 4. This stable prostacyclin analogue provided a degree of protection against canine renal allograft rejection. Images Figs. 1A and B. PMID:3545109

Near-Field Receiving Water Monitoring of Trace Metals and a Benthic Community Near the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay, California: 2007

USGS Publications Warehouse

Lorenzi, Allison H.; Cain, Daniel J.; Parcheso, Francis; Thompson, Janet K.; Luoma, Samuel N.; Hornberger, Michelle I.; Dyke, Jessica

2008-01-01

Results reported herein include trace element concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica (Cohen and Carlton 1995)), clam reproductive activity, and benthic macroinvertebrate community structure for a mudflat one kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay. This report includes data collected for the period January 2007 to December 2007, and extends a critical long-term biogeochemical record dating back to 1974. These data serve as the basis for the City of Palo Alto?s Near-Field Receiving Water Monitoring Program, initiated in 1994. Metal concentrations in both sediments and clam tissue during 2007 remained consistent with results observed since 1990. Most notably, copper and silver concentrations in sediment and clam tissue are elevated for the second consecutive year, but the values remain well within the range of past findings. Other metals such as chromium, nickel, vanadium, and zinc remained relatively constant throughout the year except for maximum values that generally occur in winter months (January-March). Mercury levels in sediment and clam tissue were some of the lowest seen on record. Last year?s elevated selenium levels appear to be transient, and selenium concentrations have returned to background levels. Overall, metal concentrations in sediments and tissue remain within past findings. Analyses of the benthic-community structure of a mudflat in South San Francisco Bay over a 31-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinel clam, M. petalum, from the same area. Analysis of the reproductive activity of M. petalum shows increases in reproductive activity concurrent with the decline in metal concentrations in the tissues of this organism. Reproductive activity is presently stable, with almost all animals initiating reproduction in the fall and spawning the following spring of most years. The community has shifted from being dominated by several opportunistic species to a community where the species are more similar in abundance, a pattern that suggests a more stable community that is subjected to less stress. In addition, two of the opportunistic species (Ampelisca abdita and Streblospio benedicti) that brood their young and live on the surface of the sediment in tubes, have shown a continual decline in dominance coincident with the decline in metals. Heteromastus filiformis, a subsurface polychaete worm that lives in the sediment, consumes sediment and organic particles residing in the sediment, and reproduces by laying their eggs on or in the sediment, has shown a concurrent increase in dominance and is now showing signs of population stability. These changes in species dominance reflect a change in the community from one dominated by surface dwelling, brooding species to one with species with varying life history characteristics.

Responses of microbial capacity and community on the performance of mesophilic co-digestion of food waste and waste activated sludge in a high-frequency feeding CSTR.

PubMed

Li, Qian; Yuwen, Chaosui; Cheng, Xinru; Yang, Xiaohuan; Chen, Rong; Wang, Xiaochang C

2018-07-01

To understand the relationship between microbes and digester performance of high-frequency feeding CSTR, which could achieve stable CH 4 production at high OLR by easing instantaneous feeding shock, attentions were paid on the variations of methanogenic capacity (MC) and microbial community with OLR increasing. Results showed that the MC for feedstock degradation could satisfy the need of effective conversion from feedstock to CH 4 when the OLR remained below 16.4 g-TS/L/d. Furthermore, the MC for acetate, propionate and butyrate degradation increased by 73.8%, 303%, and 164%, respectively, with OLR increasing from 3.03 g-TS/L/d 12.6 g-TS/L/d. The evolution of both bacterial and archaeal communities provided additional information on the adaptation of functional microbes to environmental factors. The significant increase of abundance of Methanoculleus and Methanomassiliicoccus likely promoted the utilization of H 2 , thus facilitating syntrophic methanogenesis, and consequently ensuring efficient CH 4 production in stable stage. Copyright © 2018 Elsevier Ltd. All rights reserved.

Enzymatic degradation of endomorphins.

PubMed

Janecka, Anna; Staniszewska, Renata; Gach, Katarzyna; Fichna, Jakub

2008-11-01

Centrally acting plant opiates, such as morphine, are the most frequently used analgesics for the relief of severe pain, even though their undesired side effects are serious limitation to their usefulness. The search for new therapeutics that could replace morphine has been mainly focused on the development of peptide analogs or peptidomimetics with high selectivity for one receptor type and high bioavailability, that is good blood-brain barrier permeability and enzymatic stability. Drugs, in order to be effective, must be able to reach the target tissue and to remain metabolically stable to produce the desired effects. The study of naturally occurring peptides provides a rational and powerful approach in the design of peptide therapeutics. Endogenous opioid peptides, endomorphin-1 and endomorphin-2, are two potent and highly selective mu-opioid receptor agonists, discovered only a decade ago, which display potent analgesic activity. However, extensive studies on the possible use of endomorphins as analgesics instead of morphine met with failure due to their instability. This review deals with the recent investigations that allowed determine degradation pathways of endomorphins in vitro and in vivo and propose modifications that will lead to more stable analogs.

Enhanced thermal stability of a polymer solar cell blend induced by electron beam irradiation in the transmission electron microscope.

PubMed

Bäcke, Olof; Lindqvist, Camilla; de Zerio Mendaza, Amaia Diaz; Gustafsson, Stefan; Wang, Ergang; Andersson, Mats R; Müller, Christian; Kristiansen, Per Magnus; Olsson, Eva

2017-05-01

We show by in situ microscopy that the effects of electron beam irradiation during transmission electron microscopy can be used to lock microstructural features and enhance the structural thermal stability of a nanostructured polymer:fullerene blend. Polymer:fullerene bulk-heterojunction thin films show great promise for use as active layers in organic solar cells but their low thermal stability is a hindrance. Lack of thermal stability complicates manufacturing and influences the lifetime of devices. To investigate how electron irradiation affects the thermal stability of polymer:fullerene films, a model bulk-heterojunction film based on a thiophene-quinoxaline copolymer and a fullerene derivative was heat-treated in-situ in a transmission electron microscope. In areas of the film that exposed to the electron beam the nanostructure of the film remained stable, while the nanostructure in areas not exposed to the electron beam underwent large phase separation and nucleation of fullerene crystals. UV-vis spectroscopy shows that the polymer:fullerene films are stable for electron doses up to 2000kGy. Copyright © 2016 Elsevier B.V. All rights reserved.

Enhanced thermal stability of a polymer solar cell blend induced by electron beam irradiation in the transmission electron microscope.

PubMed

Bäcke, Olof; Lindqvist, Camilla; de Zerio Mendaza, Amaia Diaz; Gustafsson, Stefan; Wang, Ergang; Andersson, Mats R; Müller, Christian; Kristiansen, Per Magnus; Olsson, Eva

2017-02-01

We show by in situ microscopy that the effects of electron beam irradiation during transmission electron microscopy can be used to lock microstructural features and enhance the structural thermal stability of a nanostructured polymer:fullerene blend. Polymer:fullerene bulk-heterojunction thin films show great promise for use as active layers in organic solar cells but their low thermal stability is a hindrance. Lack of thermal stability complicates manufacturing and influences the lifetime of devices. To investigate how electron irradiation affects the thermal stability of polymer:fullerene films, a model bulk-heterojunction film based on a thiophene-quinoxaline copolymer and a fullerene derivative was heat-treated in-situ in a transmission electron microscope. In areas of the film that exposed to the electron beam the nanostructure of the film remained stable, while the nanostructure in areas not exposed to the electron beam underwent large phase separation and nucleation of fullerene crystals. UV-vis spectroscopy shows that the polymer:fullerene films are stable for electron doses up to 2000kGy. Copyright © 2017 Elsevier B.V. All rights reserved.

Vertically uniform formation pathways of tropospheric sulfate aerosols in East China detected from triple stable oxygen and radiogenic sulfur isotopes

NASA Astrophysics Data System (ADS)

Lin, Mang; Biglari, Saman; Zhang, Zhisheng; Crocker, Daniel; Tao, Jun; Su, Binbin; Liu, Lanzhong; Thiemens, Mark H.

2017-05-01

Sulfate aerosols (SO42-) in the continental outflow from East China significantly alter the atmospheric sulfur budget across the Pacific Rim, but its formation pathways, especially in the free troposphere (FT), remain poorly understood. Here we analyze stable oxygen (δ17O and δ18O) and radiogenic sulfur (35S) isotopes in SO42- collected at a mountain site in East China to investigate SO42- formation pathways at varying altitudes. We find that Δ17O (=δ17O-0.52 × δ18O) in SO42- is not correlated with 35S (a direct measure of high-altitude air masses). This pattern notably differs from the currently known 35S-Δ17O relation. The result implies that the formation pathway of tropospheric SO42- in East China is vertically uniform, likely due to large emissions and active convection in this region. Our measurements provide unambiguous isotopic constraints for reducing uncertainties in modeling SO42- in the FT over East China, which greatly affects regional climate but current models fail to accurately estimate.

Facile synthesis of high-temperature (1000 °C) phase-stable rice-like anatase TiO2 nanocrystals

NASA Astrophysics Data System (ADS)

Lv, Lizhen; Chen, Qirong; Liu, Xiuyun; Wang, Miaomiao; Meng, Xiangfu

2015-05-01

High-temperature phase-stable rice-like anatase TiO2 nanocrystals were synthesized by one-pot solvothermal method using soluble titania xerogel and isopropyl alcohol (IPA) as the precursor and the solvent, respectively. Sample characterization was carried out by powder X-ray diffraction, high-resolution transmission electron microscopy, field emission scanning electron microscope, X-ray photoelectron spectroscopy, and N2 adsorption-desorption isotherms. The results showed that TiO2 nanocrystals had rice-like shapes with an average size of 5 nm in width and 35 nm in length. The BET surface area was 153 m2/g. Unexpectedly, the rice-like TiO2 nanocrystals exhibited high-temperature phase stability, which could remain as pure anatase phase after calcinations at 1000 °C. Growth mechanism investigation revealed that the IPA solvent played a key role in nucleation and growth of rice-like anatase TiO2 nanocrystals. The photodegradation of rhodamine B demonstrated that rice-like anatase TiO2 nanocrystals exhibited enhanced photocatalytic activity under visible light irradiation.

Single embryo transfer - state of the art.

PubMed

De Neubourg, Diane; Gerris, Jan

2003-12-01

Every practitioner active in the field of assisted reproduction treatment is aware of the risks and complications related to twin and higher-order multiple pregnancies. Introduction of single embryo transfer (SET) into IVF/intracytoplasmic sperm injection (ICSI) is one of the possible ways of reducing the rate of twin pregnancy. Careful selection of patients, in combination with elective SET, has been shown to decrease the twin pregnancy rate while maintaining a stable ongoing pregnancy rate. The combination of a woman younger than 38 years of age, in her first or second IVF/ICSI cycle and with an embryo with a high implantation potential is the key to successful SET. This article will discuss embryo selection and patient selection and review the data published on SET. In the Centre for Reproductive Medicine at Middelheim Hospital, 39% of all transfers in 2002 were SET; the ongoing pregnancy rate remained stable at 30.6%. The twin (multiple) pregnancy rate declined to 11.7%. Particular attention should be drawn to the augmenting effect of the pregnancy rate of frozen-thawed cycles. Health economic data available so far subscribe the plea for SET.

Trends in risk factors for coronary heart disease in the Netherlands.

PubMed

Koopman, C; Vaartjes, I; Blokstra, A; Verschuren, W M M; Visser, M; Deeg, D J H; Bots, M L; van Dis, I

2016-08-19

Favourable trends in risk factor levels in the general population may partly explain the decline in coronary heart disease (CHD) morbidity and mortality. Our aim was to present long-term national trends in established risk factors for CHD. Data were obtained from five data sources including several large scale population based surveys, cohort studies and general practitioner registers between 1988 and 2012. We applied linear regression models to age-standardized time trends to test for statistical significant trends. Analyses were stratified by sex and age (younger <65 and older ≥65 years adults). The results demonstrated favourable trends in smoking (except in older women) and physical activity (except in older men). Unfavourable trends were found for body mass index (BMI) and diabetes mellitus prevalence. Although systolic blood pressure (SBP) and total cholesterol trends were favourable for older persons, SBP and total cholesterol remained stable in younger persons. Four out of six risk factors for CHD showed a favourable or stable trend. The rise in diabetes mellitus and BMI is worrying with respect to CHD morbidity and mortality.

Autocrine IL-6 mediates pituitary tumor senescence

PubMed Central

Fuertes, Mariana; Ajler, Pablo; Carrizo, Guillermo; Cervio, Andrés; Sevlever, Gustavo; Stalla, Günter K.; Arzt, Eduardo

2017-01-01

Cellular senescence is a stable proliferative arrest state. Pituitary adenomas are frequent and mostly benign, but the mechanism for this remains unknown. IL-6 is involved in pituitary tumor progression and is produced by the tumoral cells. In a cell autonomous fashion, IL-6 participates in oncogene-induced senescence in transduced human melanocytes. Here we prove that autocrine IL-6 participates in pituitary tumor senescence. Endogenous IL-6 inhibition in somatotroph MtT/S shRNA stable clones results in decreased SA-β-gal activity and p16INK4a but increased pRb, proliferation and invasion. Nude mice injected with IL-6 silenced clones develop tumors contrary to MtT/S wild type that do not, demonstrating that clones that escape senescence are capable of becoming tumorigenic. When endogenous IL-6 is silenced, cell cultures derived from positive SA-β-gal human tumor samples decrease the expression of the senescence marker. Our results establish that IL-6 contributes to maintain senescence by its autocrine action, providing a natural model of IL-6 mediated benign adenoma senescence. PMID:27902467

App Usage Factor: A Simple Metric to Compare the Population Impact of Mobile Medical Apps

PubMed Central

Wyatt, Jeremy C

2015-01-01

Background One factor when assessing the quality of mobile apps is quantifying the impact of a given app on a population. There is currently no metric which can be used to compare the population impact of a mobile app across different health care disciplines. Objective The objective of this study is to create a novel metric to characterize the impact of a mobile app on a population. Methods We developed the simple novel metric, app usage factor (AUF), defined as the logarithm of the product of the number of active users of a mobile app with the median number of daily uses of the app. The behavior of this metric was modeled using simulated modeling in Python, a general-purpose programming language. Three simulations were conducted to explore the temporal and numerical stability of our metric and a simulated app ecosystem model using a simulated dataset of 20,000 apps. Results Simulations confirmed the metric was stable between predicted usage limits and remained stable at extremes of these limits. Analysis of a simulated dataset of 20,000 apps calculated an average value for the app usage factor of 4.90 (SD 0.78). A temporal simulation showed that the metric remained stable over time and suitable limits for its use were identified. Conclusions A key component when assessing app risk and potential harm is understanding the potential population impact of each mobile app. Our metric has many potential uses for a wide range of stakeholders in the app ecosystem, including users, regulators, developers, and health care professionals. Furthermore, this metric forms part of the overall estimate of risk and potential for harm or benefit posed by a mobile medical app. We identify the merits and limitations of this metric, as well as potential avenues for future validation and research. PMID:26290093

Chronic Electrical Stimulation with a Suprachoroidal Retinal Prosthesis: A Preclinical Safety and Efficacy Study

PubMed Central

Nayagam, David A. X.; Williams, Richard A.; Allen, Penelope J.; Shivdasani, Mohit N.; Luu, Chi D.; Salinas-LaRosa, Cesar M.; Finch, Sue; Ayton, Lauren N.; Saunders, Alexia L.; McPhedran, Michelle; McGowan, Ceara; Villalobos, Joel; Fallon, James B.; Wise, Andrew K.; Yeoh, Jonathan; Xu, Jin; Feng, Helen; Millard, Rodney; McWade, Melanie; Thien, Patrick C.; Williams, Chris E.; Shepherd, Robert K.

2014-01-01

Purpose To assess the safety and efficacy of chronic electrical stimulation of the retina with a suprachoroidal visual prosthesis. Methods Seven normally-sighted feline subjects were implanted for 96–143 days with a suprachoroidal electrode array and six were chronically stimulated for 70–105 days at levels that activated the visual cortex. Charge balanced, biphasic, current pulses were delivered to platinum electrodes in a monopolar stimulation mode. Retinal integrity/function and the mechanical stability of the implant were assessed monthly using electroretinography (ERG), optical coherence tomography (OCT) and fundus photography. Electrode impedances were measured weekly and electrically-evoked visual cortex potentials (eEVCPs) were measured monthly to verify that chronic stimuli were suprathreshold. At the end of the chronic stimulation period, thresholds were confirmed with multi-unit recordings from the visual cortex. Randomized, blinded histological assessments were performed by two pathologists to compare the stimulated and non-stimulated retina and adjacent tissue. Results All subjects tolerated the surgical and stimulation procedure with no evidence of discomfort or unexpected adverse outcomes. After an initial post-operative settling period, electrode arrays were mechanically stable. Mean electrode impedances were stable between 11–15 kΩ during the implantation period. Visually-evoked ERGs & OCT were normal, and mean eEVCP thresholds did not substantially differ over time. In 81 of 84 electrode-adjacent tissue samples examined, there were no discernible histopathological differences between stimulated and unstimulated tissue. In the remaining three tissue samples there were minor focal fibroblastic and acute inflammatory responses. Conclusions Chronic suprathreshold electrical stimulation of the retina using a suprachoroidal electrode array evoked a minimal tissue response and no adverse clinical or histological findings. Moreover, thresholds and electrode impedance remained stable for stimulation durations of up to 15 weeks. This study has demonstrated the safety and efficacy of suprachoroidal stimulation with charge balanced stimulus currents. PMID:24853376

Purification of Peroxisomes and Mitochondria from Spinach Leaf by Percoll Gradient Centrifugation 1

PubMed Central

Schwitzguebel, Jean-Paul; Siegenthaler, Paul-André

1984-01-01

A procedure was developed to purify simultaneously peroxisomes and mitochondria from spinach (Spinacia oleracea L.) leaf under isoosmotic and low viscosity conditions. This method involved differential centrifugation and density gradient centrifugation on four layers of Percoll. Chlorophyll-free preparations of highly intact and active organelles were obtained and cross-contamination was negligible. Both organelles were stable for several hours, even if they remained in Percoll. Purified mitochondria were able to carry out the oxidation of different substrates with excellent respiratory control and ADP:O ratios. The method described in the present work was also suitable to purify mitochondria and peroxisomes from potato (Solanum tuberosum L.) tubers. PMID:16663685

Tennessee's forest land area was stable 1999-2005 but early successional forest area declined

Treesearch

Christopher M. Oswalt

2008-01-01

A new analysis of the most recent (2005) annualized moving average data for Tennessee indicates that the area of forest land in the State remained stable between 1999 and 2005. Although trends in forest land area vary from region to region within the State, Tennessee neither lost nor gained forest land between 1999 and 2005. However, Tennessee had more than 2.5 times...

Stable Water Use Efficiency under Climate Change of Three Sympatric Conifer Species at the Alpine Treeline.

PubMed

Wieser, Gerhard; Oberhuber, Walter; Gruber, Andreas; Leo, Marco; Matyssek, Rainer; Grams, Thorsten Erhard Edgar

2016-01-01

The ability of treeline associated conifers in the Central Alps to cope with recent climate warming and increasing CO2 concentration is still poorly understood. We determined tree ring stable carbon and oxygen isotope ratios of Pinus cembra, Picea abies, and Larix decidua trees from 1975 to 2010. Stable isotope ratios were compared with leaf level gas exchange measurements carried out in situ between 1979 and 2007. Results indicate that tree ring derived intrinsic water-use efficiency (iWUE) of P. cembra, P. abies and L. decidua remained constant during the last 36 years despite climate warming and rising atmospheric CO2. Temporal patterns in Δ(13)C and Δ(18)O mirrored leaf level gas exchange assessments, suggesting parallel increases of CO2-fixation and stomatal conductance of treeline conifer species. As at the study site soil water availability was not a limiting factor iWUE remained largely stable throughout the study period. The stability in iWUE was accompanied by an increase in basal area increment (BAI) suggesting that treeline trees benefit from both recent climate warming and CO2 fertilization. Finally, our results suggest that iWUE may not change species composition at treeline in the Austrian Alps due to similar ecophysiological responses to climatic changes of the three sympatric study species.

Alkali metal pool boiler life tests for a 25 kWe advanced Stirling conversion system

NASA Technical Reports Server (NTRS)

Anderson, W. G.; Rosenfeld, J. H.; Noble, J.

1991-01-01

The overall operating temperature and efficiency of solar-powered Stirling engines can be improved by adding an alkali metal pool boiler heat transport system to supply heat more uniformly to the heater head tubes. One issue with liquid metal pool boilers is unstable boiling. Stable boiling is obtained with an enhanced boiling surface containing nucleation sites that promote continuous boiling. Over longer time periods, it is possible that the boiling behavior of the system will change. An 800-h life test was conducted to verify that pool boiling with the chosen fluid/surface combination remains stable as the system ages. The apparatus uses NaK boiling on a - 100 + 140 stainless steel sintered porous layer, with the addition of a small amount of xenon. Pool boiling remained stable to the end of life test. The pool boiler life test included a total of 82 cold starts, to simulate startup each morning, and 60 warm restarts, to simulate cloud cover transients. The behavior of the cold and warm starts showed no significant changes during the life test. In the experiments, the fluid/surface combination provided stable, high-performance boiling at the operating temperature of 700 C. Based on these experiments, a pool boiler was designed for a full-scale 25-kWe Stirling system.

An Update on the Global Initiative for Chronic Obstructive Lung Disease 2017 Guidelines With a Focus on Classification and Management of Stable COPD.

PubMed

Burkes, Robert M; Donohue, James F

2018-06-01

The 2017 Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines offer important changes to the assessment and management of stable COPD of importance to practitioners, respiratory therapists, pharmacists, and nurses who care for patients with COPD. Therapies are now chosen based on the burden of symptoms and the history of COPD exacerbations, and inhaler regimens are modifiable based on continual clinical reassessment. Although identifying the degree of airway obstruction remains important for informing the clinical status of the patient with COPD, FEV 1 is no longer used to direct the therapeutic approach. Therapies and modes of inhaled medication delivery for each GOLD grouping have been modified and reflect the need for reevaluation of patient symptoms and COPD exacerbation history as an indicator to add or withdraw therapies. As the knowledge of this important disease continues to expand, exacerbation and symptom prevention in patients with stable COPD will remain as an important target of COPD therapies and research. Novel drug combinations and delivery devices are sure to positively affect the practitioner's approach to patients with stable COPD. The new 2017 GOLD guidelines represent a step toward personalized care of the patient with COPD. Copyright © 2018 by Daedalus Enterprises.

Results of the engineering run of the Coherent Neutrino Nucleus Interaction Experiment (CONNIE)

NASA Astrophysics Data System (ADS)

Aguilar-Arevalo, A.; Bertou, X.; Bonifazi, C.; Butner, M.; Cancelo, G.; Castañeda Vázquez, A.; Cervantes Vergara, B.; Chavez, C. R.; Da Motta, H.; D'Olivo, J. C.; Dos Anjos, J.; Estrada, J.; Fernandez Moroni, G.; Ford, R.; Foguel, A.; Hernández Torres, K. P.; Izraelevitch, F.; Kavner, A.; Kilminster, B.; Kuk, K.; Lima, H. P., Jr.; Makler, M.; Molina, J.; Moreno-Granados, G.; Moro, J. M.; Paolini, E. E.; Sofo Haro, M.; Tiffenberg, J.; Trillaud, F.; Wagner, S.

2016-07-01

The CONNIE detector prototype is operating at a distance of 30 m from the core of a 3.8 GWth nuclear reactor with the goal of establishing Charge-Coupled Devices (CCD) as a new technology for the detection of coherent elastic neutrino-nucleus scattering. We report on the results of the engineering run with an active mass of 4 g of silicon. The CCD array is described, and the performance observed during the first year is discussed. A compact passive shield was deployed around the detector, producing an order of magnitude reduction in the background rate. The remaining background observed during the run was stable, and dominated by internal contamination in the detector packaging materials. The in-situ calibration of the detector using X-ray lines from fluorescence demonstrates good stability of the readout system. The event rates with the reactor ON and OFF are compared, and no excess is observed coming from nuclear fission at the power plant. The upper limit for the neutrino event rate is set two orders of magnitude above the expectations for the standard model. The results demonstrate the cryogenic CCD-based detector can be remotely operated at the reactor site with stable noise below 2 e- RMS and stable background rates. The success of the engineering test provides a clear path for the upgraded 100 g detector to be deployed during 2016.

The production and uses of Beauveria bassiana as a microbial insecticide.

PubMed

Mascarin, Gabriel Moura; Jaronski, Stefan T

2016-11-01

Among invertebrate fungal pathogens, Beauveria bassiana has assumed a key role in management of numerous arthropod agricultural, veterinary and forestry pests. Beauveria is typically deployed in one or more inundative applications of large numbers of aerial conidia in dry or liquid formulations, in a chemical paradigm. Mass production is mainly practiced by solid-state fermentation to yield hydrophobic aerial conidia, which remain the principal active ingredient of mycoinsecticides. More robust and cost-effective fermentation and formulation downstream platforms are imperative for its overall commercialization by industry. Hence, where economics allow, submerged liquid fermentation provides alternative method to produce effective and stable propagules that can be easily formulated as dry stable preparations. Formulation also continues to be a bottleneck in the development of stable and effective commercial Beauveria-mycoinsecticides in many countries, although good commercial formulations do exist. Future research on improving fermentation and formulation technologies coupled with the selection of multi-stress tolerant and virulent strains is needed to catalyze the widespread acceptance and usefulness of this fungus as a cost-effective mycoinsecticide. The role of Beauveria as one tool among many in integrated pest management, rather than a stand-alone management approach, needs to be better developed across the range of crop systems. Here, we provide an overview of mass-production and formulation strategies, updated list of registered commercial products, major biocontrol programs and ecological aspects affecting the use of Beauveria as a mycoinsecticide.

Optimizing sample pretreatment for compound-specific stable carbon isotopic analysis of amino sugars in marine sediment

NASA Astrophysics Data System (ADS)

Zhu, R.; Lin, Y.-S.; Lipp, J. S.; Meador, T. B.; Hinrichs, K.-U.

2014-01-01

Amino sugars are quantitatively significant constituents of soil and marine sediment, but their sources and turnover in environmental samples remain poorly understood. The stable carbon isotopic composition of amino sugars can provide information on the lifestyles of their source organisms and can be monitored during incubations with labeled substrates to estimate the turnover rates of microbial populations. However, until now, such investigation has been carried out only with soil samples, partly because of the much lower abundance of amino sugars in marine environments. We therefore optimized a procedure for compound-specific isotopic analysis of amino sugars in marine sediment employing gas chromatography-isotope ratio mass spectrometry. The whole procedure consisted of hydrolysis, neutralization, enrichment, and derivatization of amino sugars. Except for the derivatization step, the protocol introduced negligible isotopic fractionation, and the minimum requirement of amino sugar for isotopic analysis was 20 ng, i.e. equivalent to ~ 8 ng of amino sugar carbon. Our results obtained from δ13C analysis of amino sugars in selected marine sediment samples showed that muramic acid had isotopic imprints from indigenous bacterial activities, whereas glucosamine and galactosamine were mainly derived from organic detritus. The analysis of stable carbon isotopic compositions of amino sugars opens a promising window for the investigation of microbial metabolisms in marine sediments and the deep marine biosphere.

Optimizing sample pretreatment for compound-specific stable carbon isotopic analysis of amino sugars in marine sediment

NASA Astrophysics Data System (ADS)

Zhu, R.; Lin, Y.-S.; Lipp, J. S.; Meador, T. B.; Hinrichs, K.-U.

2014-09-01

Amino sugars are quantitatively significant constituents of soil and marine sediment, but their sources and turnover in environmental samples remain poorly understood. The stable carbon isotopic composition of amino sugars can provide information on the lifestyles of their source organisms and can be monitored during incubations with labeled substrates to estimate the turnover rates of microbial populations. However, until now, such investigation has been carried out only with soil samples, partly because of the much lower abundance of amino sugars in marine environments. We therefore optimized a procedure for compound-specific isotopic analysis of amino sugars in marine sediment, employing gas chromatography-isotope ratio mass spectrometry. The whole procedure consisted of hydrolysis, neutralization, enrichment, and derivatization of amino sugars. Except for the derivatization step, the protocol introduced negligible isotopic fractionation, and the minimum requirement of amino sugar for isotopic analysis was 20 ng, i.e., equivalent to ~8 ng of amino sugar carbon. Compound-specific stable carbon isotopic analysis of amino sugars obtained from marine sediment extracts indicated that glucosamine and galactosamine were mainly derived from organic detritus, whereas muramic acid showed isotopic imprints from indigenous bacterial activities. The δ13C analysis of amino sugars provides a valuable addition to the biomarker-based characterization of microbial metabolism in the deep marine biosphere, which so far has been lipid oriented and biased towards the detection of archaeal signals.

Deregulated activation of oncoprotein kinase Tpl2/Cot in HTLV-I-transformed T cells.

PubMed

Babu, Geetha; Waterfield, Michael; Chang, Mikyoung; Wu, Xuefeng; Sun, Shao-Cong

2006-05-19

Protein kinase Tpl2/Cot is encoded by a protooncogene that is cis-activated by retroviral insertion in murine T cell lymphomas. It has remained unclear whether this oncoprotein kinase is mutated or post-translationally activated in human cancer cells. We have shown here that Tpl2/Cot is constitutively activated in human leukemia cell lines transformed by the human T cell leukemia virus type I (HTLV-I). The kinase activity of Tpl2/Cot is normally suppressed through its physical interaction with an inhibitor, the NF-kappaB1 precursor protein p105. Interestingly, a large pool of Tpl2/Cot is liberated from p105 and exhibits constitutive kinase activity in HTLV-I-transformed T cells. In contrast to its labile property in normal cells, the pathologically activated Tpl2/Cot is remarkably stable. Further, whereas the physiological activation of Tpl2/Cot involves its long isoform, the HTLV-activated Tpl2/Cot is predominantly the short isoform. We have also shown that the HTLV-I-encoded Tax protein is able to activate Tpl2/Cot in transfected cells. Finally, Tpl2/Cot participates in the activation of NF-kappaB by Tax. These findings indicate that deregulated activation of Tpl2/Cot may occur in human cancer cells.

The potential of virtual reality-based training to enhance the functional autonomy of Alzheimer's disease patients in cooking activities: A single case study.

PubMed

Foloppe, Déborah A; Richard, Paul; Yamaguchi, Takehiko; Etcharry-Bouyx, Frédérique; Allain, Philippe

2018-07-01

Impairments in performing activities of daily living occur early in the course of Alzheimer's disease (AD). There is a great need to develop non-pharmacological therapeutic interventions likely to reduce dependency in everyday activities in AD patients. This study investigated whether it was possible to increase autonomy in these patients in cooking activities using interventions based on errorless learning, vanishing-cue, and virtual reality techniques. We recruited a 79-year-old woman who met NINCDS-ADRDA criteria for probable AD. She was trained in four cooking tasks for four days per task, one hour per day, in virtual and in real conditions. Outcome measures included subjective data concerning the therapeutic intervention and the experience of virtual reality, repeated assessments of training activities, neuropsychological scores, and self-esteem and quality of life measures. The results indicated that our patient could relearn some cooking activities using virtual reality techniques. Transfer to real life was also observed. Improvement of the task performance remained stable over time. This case report supports the value of a non-immersive virtual kitchen to help people with AD to relearn cooking activities.

Methyl Fluoride Affects Methanogenesis Rather than Community Composition of Methanogenic Archaea in a Rice Field Soil

PubMed Central

Daebeler, Anne; Gansen, Martina; Frenzel, Peter

2013-01-01

The metabolic pathways of methane formation vary with environmental conditions, but whether this can also be linked to changes in the active archaeal community structure remains uncertain. Here, we show that the suppression of aceticlastic methanogenesis by methyl fluoride (CH3F) caused surprisingly little differences in community composition of active methanogenic archaea from a rice field soil. By measuring the natural abundances of carbon isotopes we found that the effective dose for a 90% inhibition of aceticlastic methanogenesis in anoxic paddy soil incubations was <0.75% CH3F (v/v). The construction of clone libraries as well as t-RFLP analysis revealed that the active community, as indicated by mcrA transcripts (encoding the α subunit of methyl-coenzyme M reductase, a key enzyme for methanogenesis), remained stable over a wide range of CH3F concentrations and represented only a subset of the methanogenic community. More precisely, Methanocellaceae were of minor importance, but Methanosarcinaceae dominated the active population, even when CH3F inhibition only allowed for aceticlastic methanogenesis. In addition, we detected mcrA gene fragments of a so far unrecognised phylogenetic cluster. Transcription of this phylotype at methyl fluoride concentrations suppressing aceticlastic methanogenesis suggests that the respective organisms perform hydrogenotrophic methanogenesis. Hence, the application of CH3F combined with transcript analysis is not only a useful tool to measure and assign in situ acetate usage, but also to explore substrate usage by as yet uncultivated methanogens. PMID:23341965

FOXO/DAF-16 Activation Slows Down Turnover of the Majority of Proteins in C. elegans

DOE PAGES

Dhondt, Ineke; Petyuk, Vladislav A.; Cai, Huaihan; ...

2016-09-13

Most aging hypotheses assume the accumulation of damage, resulting in gradual physiological decline and, ultimately, death. Avoiding protein damage accumulation by enhanced turnover should slow down the aging process and extend the lifespan. But, lowering translational efficiency extends rather than shortens the lifespan in C. elegans. We studied turnover of individual proteins in the long-lived daf-2 mutant by combining SILeNCe (stable isotope labeling by nitrogen in Caenorhabditiselegans) and mass spectrometry. Intriguingly, the majority of proteins displayed prolonged half-lives in daf-2, whereas others remained unchanged, signifying that longevity is not supported by high protein turnover. We found that this slowdown wasmore » most prominent for translation-related and mitochondrial proteins. Conversely, the high turnover of lysosomal hydrolases and very low turnover of cytoskeletal proteins remained largely unchanged. The slowdown of protein dynamics and decreased abundance of the translational machinery may point to the importance of anabolic attenuation in lifespan extension, as suggested by the hyperfunction theory.« less

Stability of natamycin and its cyclodextrin inclusion complexes in aqueous solution.

PubMed

Koontz, John L; Marcy, Joseph E; Barbeau, William E; Duncan, Susan E

2003-11-19

Aqueous solutions of natamycin and its beta-cyclodextrin (beta-CD), hydroxypropyl beta-cyclodextrin, and gamma-cyclodextrin (gamma-CD) inclusion complexes were completely degraded after 24 h of exposure to 1000 lx fluorescent lighting at 4 degrees C. After 14 days of storage in darkness at 4 degrees C, 92.2% of natamycin remained in active form. The natamycin:beta-CD complex and natamycin:gamma-CD complex were significantly more stable (p < 0.05) than natamycin in its free state in aqueous solutions stored in darkness at 4 degrees C. Clear poly(ethylene terephthalate) packaging with a UV light absorber allowed 85.0% of natamycin to remain after 14 days of storage under 1000 lx fluorescent lighting at 4 degrees C. Natamycin:cyclodextrin complexes can be dissociated for analysis in methanol/water/acetic acid, 60:40:5, v/v/v. Natamycin and its complexes in dissociated form were quantified by reverse phase HPLC with detection by photodiode array at 304 nm.

Acute on Chronic Ivabradine Overdose: a Case Report.

PubMed

Maskell, Kevin; Tse, Adele; Wolf, Carl E; Troendle, Michelle

2016-06-01

Ivabradine is a newly approved medication which reduces the heart rate by antagonizing the If channel. We report a case of intentional overdose on ivabradine. A 26-year-old female presented after taking 250 mg ivabradine. On arrival, her vital signs and neurologic exam were unremarkable. Within 30 min, her heart rate decreased to 31 bpm, but she remained normotensive with no change in mentation. Her bradycardia resolved after treatment with atropine. She experienced two further bradycardic episodes responsive to atropine; the second episode was associated with hypotension, responsive to a fluid bolus. For the remainder of her hospitalization, she remained hemodynamically stable without further interventions. She was dispositioned to the psychiatry service approximately 36 h post-ingestion with a heart rate of 67 bpm. Laboratory analysis confirmed a serum ivabradine concentration of 525 ng/mL, greater than 50 times the mean level in therapeutic trials. Proposed treatments for ivabradine include activated charcoal, atropine, isoproterenol, and intravenous pacing. Further study is needed to identify ideal treatment modalities.

Health Benefits In 2016: Family Premiums Rose Modestly, And Offer Rates Remained Stable.

PubMed

Claxton, Gary; Rae, Matthew; Long, Michelle; Damico, Anthony; Whitmore, Heidi; Foster, Gregory

2016-10-01

The annual Kaiser Family Foundation/Health Research and Educational Trust Employer Health Benefits Survey found that in 2016, average annual premiums (employer and worker contributions combined) were $6,435 for single coverage and $18,142 for family coverage. The family premium in 2016 was 3 percent higher than that in 2015. On average, workers contributed 18 percent of the premium for single coverage and 30 percent for family coverage. The share of firms offering health benefits (56 percent) and of workers covered by their employers' plans (62 percent) remained statistically unchanged from 2015. Employers continued to offer financial incentives for completing wellness or health promotion activities. Almost three in ten covered workers were enrolled in a high-deductible plan with a savings option-a significant increase from 2014. The 2016 survey included new questions on cost sharing for specialty drugs and on the prevalence of incentives for employees to seek care at alternative settings. Project HOPE—The People-to-People Health Foundation, Inc.

Hemorrhagic Tamponade as Initial Manifestation of Systemic Lupus with Subsequent Refractory and Progressive Lupus Myocarditis Resulting in Cardiomyopathy and Mitral Regurgitation.

PubMed

Marijanovich, Nicole; Halalau, Alexandra

2018-01-01

Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease with a wide range of clinical and serological manifestations. Cardiac disease among patients with SLE is common and can involve the pericardium, myocardium, valves, conduction system, and coronary arteries. We are reporting a case of SLE in a young woman that is unique is unique in that initial symptoms consisted of pericarditis and hemorrhagic tamponade which remained progressive and resistant to aggressive immunosuppressive treatment and led to severe cardiomyopathy (ejection fraction of 25%) and severe (+4) mitral regurgitation. Her immunosuppressive treatment included hydroxychloroquine, high-dose steroids, intravenous immunoglobulins, azathioprine, and mycophenolate mofetil. Her disease progression was felt to be due to underlying uncontrolled SLE because the complement levels remained persistently low throughout the entire course and PET Myocardial Perfusion and Viability study showed stable persistent active inflammation. Eventually, she was treated with cyclophosphamide which led to improvement in ejection fraction to 55% with only mild mitral regurgitation.

Hemorrhagic Tamponade as Initial Manifestation of Systemic Lupus with Subsequent Refractory and Progressive Lupus Myocarditis Resulting in Cardiomyopathy and Mitral Regurgitation

PubMed Central

Marijanovich, Nicole

2018-01-01

Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease with a wide range of clinical and serological manifestations. Cardiac disease among patients with SLE is common and can involve the pericardium, myocardium, valves, conduction system, and coronary arteries. We are reporting a case of SLE in a young woman that is unique is unique in that initial symptoms consisted of pericarditis and hemorrhagic tamponade which remained progressive and resistant to aggressive immunosuppressive treatment and led to severe cardiomyopathy (ejection fraction of 25%) and severe (+4) mitral regurgitation. Her immunosuppressive treatment included hydroxychloroquine, high-dose steroids, intravenous immunoglobulins, azathioprine, and mycophenolate mofetil. Her disease progression was felt to be due to underlying uncontrolled SLE because the complement levels remained persistently low throughout the entire course and PET Myocardial Perfusion and Viability study showed stable persistent active inflammation. Eventually, she was treated with cyclophosphamide which led to improvement in ejection fraction to 55% with only mild mitral regurgitation. PMID:29610699

Gender and Facebook motives as predictors of specific types of Facebook use: A latent growth curve analysis in adolescence.

PubMed

Frison, Eline; Eggermont, Steven

2016-10-01

Despite increasing evidence that specific types of Facebook use (i.e., active private, active public, and passive Facebook use) are differently related to adolescents' well-being, little is known how these types function over the course of adolescence and whether gender and Facebook motives may predict the initial level and changes in these types over time. To address these gaps, Flemish adolescents (ages 12-19) were questioned at three different time points, with six months in between (NTime1 = 1866). Latent growth curve models revealed that active private Facebook use increased over the course of adolescence, whereas public Facebook use decreased. Passive Facebook use, however, remained stable. In addition, gender and Facebook motives were related to initial levels of specific types of Facebook use, and predictive of dynamic change in specific types of Facebook use over time. The discussion focuses on the understanding and implications of these findings. Copyright © 2016. Published by Elsevier Ltd.

Deep-biosphere methane production stimulated by geofluids in the Nankai accretionary complex

PubMed Central

Kubo, Yusuke; Hoshino, Tatsuhiko; Sakai, Sanae; Arnold, Gail L.; Case, David H.; Lever, Mark A.; Morita, Sumito; Nakamura, Ko-ichi

2018-01-01

Microbial life inhabiting subseafloor sediments plays an important role in Earth’s carbon cycle. However, the impact of geodynamic processes on the distributions and carbon-cycling activities of subseafloor life remains poorly constrained. We explore a submarine mud volcano of the Nankai accretionary complex by drilling down to 200 m below the summit. Stable isotopic compositions of water and carbon compounds, including clumped methane isotopologues, suggest that ~90% of methane is microbially produced at 16° to 30°C and 300 to 900 m below seafloor, corresponding to the basin bottom, where fluids in the accretionary prism are supplied via megasplay faults. Radiotracer experiments showed that relatively small microbial populations in deep mud volcano sediments (102 to 103 cells cm−3) include highly active hydrogenotrophic methanogens and acetogens. Our findings indicate that subduction-associated fluid migration has stimulated microbial activity in the mud reservoir and that mud volcanoes may contribute more substantially to the methane budget than previously estimated. PMID:29928689

An Optimal CDS Construction Algorithm with Activity Scheduling in Ad Hoc Networks

PubMed Central

Penumalli, Chakradhar; Palanichamy, Yogesh

2015-01-01

A new energy efficient optimal Connected Dominating Set (CDS) algorithm with activity scheduling for mobile ad hoc networks (MANETs) is proposed. This algorithm achieves energy efficiency by minimizing the Broadcast Storm Problem [BSP] and at the same time considering the node's remaining energy. The Connected Dominating Set is widely used as a virtual backbone or spine in mobile ad hoc networks [MANETs] or Wireless Sensor Networks [WSN]. The CDS of a graph representing a network has a significant impact on an efficient design of routing protocol in wireless networks. Here the CDS is a distributed algorithm with activity scheduling based on unit disk graph [UDG]. The node's mobility and residual energy (RE) are considered as parameters in the construction of stable optimal energy efficient CDS. The performance is evaluated at various node densities, various transmission ranges, and mobility rates. The theoretical analysis and simulation results of this algorithm are also presented which yield better results. PMID:26221627

Srs2 prevents Rad51 filament formation by repetitive motion on DNA.

PubMed

Qiu, Yupeng; Antony, Edwin; Doganay, Sultan; Koh, Hye Ran; Lohman, Timothy M; Myong, Sua

2013-01-01

Srs2 dismantles presynaptic Rad51 filaments and prevents its re-formation as an anti-recombinase. However, the molecular mechanism by which Srs2 accomplishes these tasks remains unclear. Here we report a single-molecule fluorescence study of the dynamics of Rad51 filament formation and its disruption by Srs2. Rad51 forms filaments on single-stranded DNA by sequential binding of primarily monomers and dimers in a 5'-3' direction. One Rad51 molecule binds to three nucleotides, and six monomers are required to achieve a stable nucleation cluster. Srs2 exhibits ATP-dependent repetitive motion on single-stranded DNA and this activity prevents re-formation of the Rad51 filament. The same activity of Srs2 cannot prevent RecA filament formation, indicating its specificity for Rad51. Srs2's DNA-unwinding activity is greatly suppressed when Rad51 filaments form on duplex DNA. Taken together, our results reveal an exquisite and highly specific mechanism by which Srs2 regulates the Rad51 filament formation.

A phenylalanine rotameric switch for signal-state control in bacterial chemoreceptors

NASA Astrophysics Data System (ADS)

Ortega, Davi R.; Yang, Chen; Ames, Peter; Baudry, Jerome; Parkinson, John S.; Zhulin, Igor B.

2013-12-01

Bacterial chemoreceptors are widely used as a model system for elucidating the molecular mechanisms of transmembrane signalling and have provided a detailed understanding of how ligand binding by the receptor modulates the activity of its associated kinase CheA. However, the mechanisms by which conformational signals move between signalling elements within a receptor dimer and how they control kinase activity remain unknown. Here, using long molecular dynamics simulations, we show that the kinase-activating cytoplasmic tip of the chemoreceptor fluctuates between two stable conformations in a signal-dependent manner. A highly conserved residue, Phe396, appears to serve as the conformational switch, because flipping of the stacked aromatic rings of an interacting F396-F396‧ pair in the receptor homodimer takes place concomitantly with the signal-related conformational changes. We suggest that interacting aromatic residues, which are common stabilizers of protein tertiary structure, might serve as rotameric molecular switches in other biological processes as well.

Highly Efficient Carbon Dioxide Hydrogenation to Methanol Catalyzed by Zigzag Platinum-Cobalt Nanowires.

PubMed

Bai, Shuxing; Shao, Qi; Feng, Yonggang; Bu, Lingzheng; Huang, Xiaoqing

2017-06-01

Carbon dioxide (CO 2 ) hydrogenation is an effective strategy for CO 2 utilization, while unsatisfied conversion efficiencies remain great challenges. It is reported herein that zigzag Pt-Co nanowires (NWs) with Pt-rich surfaces and abundant steps/edges can perform as highly active and stable CO 2 hydrogenation catalysts. It is found that tuning the Pt/Co ratio of the Pt-Co NWs, solvents, and catalyst supports could well optimize the CO 2 hydrogenation to methanol (CH 3 OH) with the Pt 4 Co NWs/C exhibiting the best performance, outperforming all the previous catalysts. They are also very durable with limited activity decays after six catalytic cycles. The diffuse reflectance infrared Fourier transform spectroscopy result of CO 2 adsorption shows that the Pt 4 Co NWs/C undergoes the adsorption/activation of CO 2 by forming appropriate carboxylate intermediates, and thus enhancing the CH 3 OH production. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

An activated energy approach for accelerated testing of the deformation of UHMWPE in artificial joints.

PubMed

Galetz, Mathias Christian; Glatzel, Uwe

2010-05-01

The deformation behavior of ultrahigh molecular polyethylene (UHMWPE) is studied in the temperature range of 23-80 degrees C. Samples are examined in quasi-static compression, tensile and creep tests to determine the accelerated deformation of UHMWPE at elevated temperatures. The deformation mechanisms under compression load can be described by one strain rate and temperature dependent Eyring process. The activation energy and volume of that process do not change between 23 degrees C and 50 degrees C. This suggests that the deformation mechanism under compression remains stable within this temperature range. Tribological tests are conducted to transfer this activated energy approach to the deformation behavior under loading typical for artificial knee joints. While this approach does not cover the wear mechanisms close to the surface, testing at higher temperatures is shown to have a significant potential to reduce the testing time for lifetime predictions in terms of the macroscopic creep and deformation behavior of artificial joints. Copyright 2010. Published by Elsevier Ltd.

Influence of Pre-Analytical Factors on Thymus- and Activation-Regulated Chemokine Quantitation in Plasma

PubMed Central

Zhao, Xuemei; Delgado, Liliana; Weiner, Russell; Laterza, Omar F.

2015-01-01

Thymus- and activation-regulated chemokine (TARC) in serum/plasma associates with the disease activity of atopic dermatitis (AD), and is a promising tool for assessing the response to the treatment of the disease. TARC also exists within platelets, with elevated levels detectable in AD patients. We examined the effects of pre-analytical factors on the quantitation of TARC in human EDTA plasma. TARC levels in platelet-free plasma were significantly lower than those in platelet-containing plasma. After freeze-thaw, TARC levels increased in platelet-containing plasma, but remained unchanged in platelet-free plasma, suggesting TARC was released from the platelets during the freeze-thaw process. In contrast, TARC levels were stable in serum independent of freeze-thaw. These findings underscore the importance of pre-analytical factors to TARC quantitation. Plasma TARC levels should be measured in platelet-free plasma for accurate quantitation. Pre-analytical factors influence the quantitation, interpretation, and implementation of circulating TARC as a biomarker for the development of AD therapeutics. PMID:28936246

A Computational Study of the Rheology and Structure of Surfactant Covered Droplets

NASA Astrophysics Data System (ADS)

Maia, Joao; Boromand, Arman; Jamali, Safa

2015-11-01

The use of different types of surface-active agents is ubiquitous practice in different industrial applications ranging from cosmetic and food industries to polymeric nano-composite and blends. This allows stable multiphasic systems like foams and emulsions to be produced. Stability and shelf-life of those products are directly determined by the efficiency of the surfactant molecules. Although the effect of molecular configuration of the surface-active molecules on the planar interfaces has been studied both experimentally and computationally, it remains challenging to track the efficiency and effectiveness of different surfactant molecules on curved interfaces. In this study we address this gap by using Dissipative Particle Dynamics, to study the effectiveness and efficiency of different surfactant molecules (linear vs. branched) on a curved interface in equilibrium and far from equilibrium. In particular, we are interested to relate interfacial properties of the surface covered droplets and its dynamics to the molecular configuration of the surface active molecules under equilibrium and far from equilibrium condition.

Metabolic behavior and enzymatic aspects of denitrifying EBPR sludge in a continuous-flow anaerobic-anoxic system.

PubMed

Zafiriadis, Ilias; Ntougias, Spyridon; Kapagiannidis, Anastasios G; Aivasidis, Alexander

2013-10-01

The metabolic aspects of enhanced biological phosphorus removal (EBPR) were investigated for the first time in a continuous-flow anaerobic-anoxic plant fed with acetate, propionate, or substrates which are involved in the tricarboxylic acid and/or glyoxylate cycle, i.e., fumarate, malate, or oxaloacetate, as the sole carbon source. Although the polyphosphate-accumulating organisms (PAOs) population remained stable with any carbon source examined, no typical EBPR metabolism was observed during fumarate, malate, or oxaloacetate utilization. Specific enzymatic activities related to EBPR were determined in activated sludge homogenates and directly correlated with the nutrient metabolic rates. The experimental results indicated the direct involvement of alkaline phosphatase, pyrophosphatase, and exopolyphosphatase in the denitrifying EBPR process. Metabolic aspects of glyoxylate cycle enzymes are discussed with regard to the biomass anaerobic and anoxic activity. Process performance was highly influenced by the kind of substrate utilized, indicating that specific metabolic pathways should be followed to favor efficient EBPR.

Respiratory Network Stability and Modulatory Response to Substance P Require Nalcn.

PubMed

Yeh, Szu-Ying; Huang, Wei-Hsiang; Wang, Wei; Ward, Christopher S; Chao, Eugene S; Wu, Zhenyu; Tang, Bin; Tang, Jianrong; Sun, Jenny J; Esther van der Heijden, Meike; Gray, Paul A; Xue, Mingshan; Ray, Russell S; Ren, Dejian; Zoghbi, Huda Y

2017-04-19

Respiration is a rhythmic activity as well as one that requires responsiveness to internal and external circumstances; both the rhythm and neuromodulatory responses of breathing are controlled by brainstem neurons in the preBötzinger complex (preBötC) and the retrotrapezoid nucleus (RTN), but the specific ion channels essential to these activities remain to be identified. Because deficiency of sodium leak channel, non-selective (Nalcn) causes lethal apnea in humans and mice, we investigated Nalcn function in these neuronal groups. We found that one-third of mice lacking Nalcn in excitatory preBötC neurons died soon after birth; surviving mice developed apneas in adulthood. Interestingly, in both preBötC and RTN neurons, the Nalcn current influences the resting membrane potential, contributes to maintenance of stable network activity, and mediates modulatory responses to the neuropeptide substance P. These findings reveal Nalcn's specific role in both rhythmic stability and responsiveness to neuropeptides within the respiratory network. Copyright © 2017 Elsevier Inc. All rights reserved.

Evaluation of the apparent diffusion coefficient in patients with recurrent glioblastoma under treatment with bevacizumab with radiographic pseudoresponse.

PubMed

A Auer, Timo; Breit, Hanns-Christian; Marini, Federico; Renovanz, Mirjam; A Brockmann, Marc; Tanyildizi, Yasemin

2018-05-04

Response Assessment in Neuro-Oncology Criteria (RANO), are used to asses response to first-line treatment of glioblastoma (GBM). Differentiation between response and pseudoresponse under treatment with Bevacizumab (BVZ) remains challenging. This study evaluates ADC changes in patients with radiographic pseudoresponse under treatment with (BVZ). Patients (n=40) with recurrent GBM under-treatment with BVZ underwent MRI before, two and four months after treatment with BVZ. In patients with radiological pseudoresponse (n=11), ADC analyses were performed. Areas with decreasing T1 contrast enhancement (CE) and FLAIR signal decrease were manually selected and compared to size and position matched healthy contralateral brain parenchyma. Histogram based ADC (10 -6 ×mm 2 /s) of these patients decreased significantly (P<0.005) from baseline MRI (T1-CE, FLAIR: 1124.9±160.3, 1098.4±226.2, respectively) to 2months (781.3±110.7, 783.3±103.3) and remained stable during 4months (777.0±138.5, 784.4±155.4, all mean±1 SD), despite progressive disease. Mean ADC values of the healthy contralateral brain tissue remained stable (P>0.05) (ADC values: baseline: 786.2±110.7, 2months: 781.1±76.2, 4months: 804.1±86.2). Treatment of GBM with BVZ leads to a decrease of ADC values in areas of pre-treatment T1-CE/FLAIR signal hyperintensity to levels of comparable with normal brain tissue. ADC values remained stable, even when progressive tumor growth was reported. Copyright © 2018. Published by Elsevier Masson SAS.

Factors Associated with Short-Term Transitions of Nondaily Smokers: Socio-demographic Characteristics and Other Tobacco Product Use

PubMed Central

Wang, Yingning; Sung, Hai-Yen; Yao, Tingting; Lightwood, James; Max, Wendy

2016-01-01

Aims To examine the transitions in smoking status among nondaily smokers who transitioned to daily or former smokers or remained as nondaily smokers over a 12-month period. We analyzed factors associated with these transitions, including the use of cigars and smokeless tobacco (SLT). Design Secondary data analyses using pooled data from the 2003, 2006/07 and 2010/11 Tobacco Use Supplements to the Current Population Survey (TUS-CPS). Setting USA Participants Self-respondents aged 18+ who have smoked for more than 5 years and were nondaily smokers 12 months before the interview (n = 13,673 or 14.5% of current smokers). Measurements Multinomial logistic regression model to determine the correlates of nondaily-to-daily, stable nondaily, and nondaily-to-former smoking transitions among nondaily smokers at baseline. The model controlled for socio-demographic factors and the use of cigars and SLT. Findings 2.6% of adults in our sample were nondaily smokers at baseline. Among these, 69.7% remained nondaily smokers (stable nondaily smokers), 18.4% became daily smokers (nondaily-to-daily smokers), and 11.9% quit smoking (nondaily-to-former smokers) after 12 months. The nondaily-to-daily vs. stable nondaily smoking transition was less likely among those who were aged 65+ (p=0.018), male (p<0.001), Hispanic (p<0.001), with income of $25,000–49,999 or ≥$75,000, and current users of SLT (p=0.003), but more likely among those without a college degree compared with the appropriate reference group. The nondaily-to-former vs. stable nondaily smoking transition was less likely among those aged 25+, male (p=0.013), non-Hispanic Asian (p=0.032), without a college degree, widowed/divorced/separated (p=0.013) or never married (p=0.011), and current users of cigars (p=0.003) compared with the appropriate reference group. Conclusions While over two-thirds of nondaily smokers in the USA remain as such after 12 months, others become daily smokers or quit. The likelihood of remaining stable nondaily smokers and of transition from nondaily-to-daily and nondaily-to-former smokers is associated with socio-demographics factors and current use of cigars and smokeless tobacco. PMID:27886652

Gene-activated fat grafts for the repair of spinal cord injury: a pilot study.

PubMed

Betz, Volker M; Sitoci-Ficici, K Hakan; Uckermann, Ortrud; Leipnitz, Elke; Iltzsche, Anne; Thirion, Christian; Salomon, Michael; Zwipp, Hans; Schackert, Gabriele; Betz, Oliver B; Kirsch, Matthias

2016-02-01

Spinal cord injury (SCI) is a complex disease requiring a concerted multi-target approach. The most appropriate combination of therapeutic gene, cellular vehicle, and space filling scaffold still has to be determined. We present an approach that employs syngeneic adipose tissue serving as a three-dimensional biological implant, source of progenitor cells, and delivery system for therapeutic genes. In this pilot experiment, we evaluated the feasibility and short-term effects using gene-activated autologous fat grafts after SCI. An experimental SCI model was established in syngeneic Fischer 344 rats by a T9-T10 hemimyelonectomy. Fat tissue was harvested from two donor rats. Animals were divided into four groups and treated with either (i) fat grafts activated by an adenoviral vector carrying the human NT-3 cDNA, (ii) or BDNF, (iii) or with untreated fat grafts or (iv) remained untreated. Animals were euthanized either 7 or 21 days after surgery, and spinal cord tissue was investigated by histological and immunohistochemical methods. NT-3 and BDNF were produced by gene-activated fat grafts for at least 21 days in vitro and in vivo. Fat tissue grafts remained stable at the site of implantation at 7 days and at 21 days. Neither BDNF-activated nor NT-3-activated fat graft had a detectable limiting effect on the neuronal degeneration. BDNF recruited microglia to perilesional site and attenuated their inflammatory response. Gene-activated syngeneic fat tissue serves as a three-dimensional biological material delivering therapeutic molecules to the site of SCI over an extended period of time. The BDNF-fat graft attenuated the inflammatory response. Whether these findings translate into functional recovery will require extended observation times.

1965 Oregon timber harvest.

Treesearch

Brian R. Wall

1966-01-01

Oregon maintained its high level of timber harvest in 1965 with an output of 9.4 billion board feet. This was the first time since 1926 that production remained unchanged in 2 consecutive years. The harvest from private lands remained stable at 4 billion feet, or 43 percent of the total. Forest industry's cut declined 2 percent (83 million board feet) from 1964,...

Phosphorylation of mitogen-activated protein kinase (MAPK) is required for cytokinesis and progression of cell cycle in tobacco BY-2 cells.

PubMed

Ma, Zhaowu; Yu, Guanghui

2010-02-15

The role of mitogen-activated protein kinase (MAPK) in plant cytokinesis remains largely uncharacterized. To elucidate its role, tobacco Bright Yellow-2 (BY-2) cells have been synchronized using a two-step procedure, and the different phases of the cell cycle identified by Histone 4 gene expression and the mitotic index. MAPK expression was analyzed by semi-quantitative (SQ) RT-PCR and protein gel blot analysis for phosphorylated MAPK during cell cycle progression. The SQ RT-PCR analysis indicated that MAPK expression is lower in mitosis than in interphase (G1, G2 and S). However, the amount of phosphorylated MAPK remained stable throughout the cell cycle, indicating that MAPK activity is predominantly regulated at the post-translational level and that phosphorylation of MAPK plays an important role in mitosis. Application of the specific MAPK phosphorylation inhibitor U0126 revealed that while U0126 treatment decreases the phosphorylation of MAPK and the progression from telophase to early cytokinesis is significantly inhibited. The formation of the phragmoplast is also negatively affected at this stage. These results demonstrate that MAPK phosphorylation is involved in the formation of the cell plate within the phragmoplast during cytokinesis and that MAPK predominantly functions during the cytokinesis stage of the cell cycle in tobacco BY-2 cells. Copyright 2009 Elsevier GmbH. All rights reserved.

Induction of plasma acetylcholinesterase activity in mice challenged with organophosphorus poisons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duysen, Ellen G.; Lockridge, Oksana, E-mail: olockrid@unmc.edu

2011-09-01

The restoration of plasma acetylcholinesterase activity in mice following inhibition by organophosphorus pesticides and nerve agents has been attributed to synthesis of new enzyme. It is generally assumed that activity levels return to normal, are stable and do not exceed the normal level. We have observed over the past 10 years that recovery of acetylcholinesterase activity levels in mice treated with organophosphorus agents (OP) exceeds pretreatment levels and remains elevated for up to 2 months. The most dramatic case was in mice treated with tri-cresyl phosphate and tri-ortho-cresyl phosphate, where plasma acetylcholinesterase activity rebounded to a level 250% higher thanmore » the pretreatment activity. The present report summarizes our observations on plasma acetylcholinesterase activity in mice treated with chlorpyrifos, chlorpyrifos oxon, diazinon, tri-ortho-cresyl phosphate, tri-cresyl phosphate, tabun thiocholine, parathion, dichlorvos, and diisopropylfluorophosphate. We have developed a hypothesis to explain the excess acetylcholinesterase activity, based on published observations. We hypothesize that acetylcholinesterase activity is induced when cells undergo apoptosis and that consequently there is a rise in the level of plasma acetylcholinesterase. - Highlights: > Acetylcholinesterase activity is induced by organophosphorus agents. > AChE induction is related to apoptosis. > Induction of AChE activity by OP is independent of BChE.« less

[A new way of financing the French healthcare system?].

PubMed

Elbaum, Mireille

2010-01-01

Several changes occurred lately in the regulation of the French healthcare system: the public health insurance deficit has been reduced until 2008, the ratio of health expenditure as percentage of GDP has remained fairly stable, activity-based payments have been implemented in public and private hospitals, and the government tried to promote more coordination and better prescriptions among practitioners. These changes have nevertheless limited impacts, and do not concern the "heart" of economic regulation: the system of prices, fees and reimbursement remains unchanged, and health insurance deficits have been repeatedly funded by new specific taxes and decreases in reimbursement. The part of expenses left to complementary insurances and out-of-pocket spending is increasing for ambulatory care, and government policies claiming for more "responsibility" in the use of health care mainly apply to patients. As these problems remain unsolved, the French health system has to tackle major short and medium-term challenges: the consolidation of deficits linked or not to the economic crisis, the long-term trend of health care expenditures resulting from population ageing, and the necessity to improve the efficiency of the system in a way which does not increase inequities in health care access.

Longitudinal CSF biomarkers in patients with early Parkinson disease and healthy controls.

PubMed

Mollenhauer, Brit; Caspell-Garcia, Chelsea J; Coffey, Christopher S; Taylor, Peggy; Shaw, Leslie M; Trojanowski, John Q; Singleton, Andy; Frasier, Mark; Marek, Kenneth; Galasko, Douglas

2017-11-07

To analyze longitudinal levels of CSF biomarkers in drug-naive patients with Parkinson disease (PD) and healthy controls (HC), examine the extent to which these biomarker changes relate to clinical measures of PD, and identify what may influence them. CSF α-synuclein (α-syn), total and phosphorylated tau (t- and p-tau), and β-amyloid 1-42 (Aβ42) were measured at baseline and 6 and 12 months in 173 patients with PD and 112 matched HC in the international multicenter Parkinson's Progression Marker Initiative. Baseline clinical and demographic variables, PD medications, neuroimaging, and genetic variables were evaluated as potential predictors of CSF biomarker changes. CSF biomarkers were stable over 6 and 12 months, and there was a small but significant increase in CSF Aβ42 in both patients with patients with PD and HC from baseline to 12 months. The t-tau remained stable. The p-tau increased marginally more in patients with PD than in HC. α-syn remained relatively stable in patients with PD and HC. Ratios of p-tau/t-tau increased, while t-tau/Aβ42 decreased over 12 months in patients with PD. CSF biomarker changes did not correlate with changes in Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale motor scores or dopamine imaging. CSF α-syn levels at 12 months were lower in patients with PD treated with dopamine replacement therapy, especially dopamine agonists. These core CSF biomarkers remained stable over 6 and 12 months in patients with early PD and HC. PD medication use may influence CSF α-syn. Novel biomarkers are needed to better profile progressive neurodegeneration in PD. Copyright © 2017 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.

Non-Acute Coronary Syndrome Anginal Chest Pain

PubMed Central

Agarwal, Megha; Mehta, Puja K.; Merz, C. Noel Bairey

2010-01-01

Anginal chest pain is one of the most common complaints in the outpatient setting. While much of the focus has been on identifying obstructive atherosclerotic coronary artery disease (CAD) as the cause of anginal chest pain, it is clear that microvascular coronary dysfunction (MCD) can also cause anginal chest pain as a manifestation of ischemic heart disease (IHD), and carries an increased cardiovascular risk. Epicardial coronary vasospasm, aortic stenosis, left ventricular hypertrophy, congenital coronary anomalies, mitral valve prolapse and abnormal cardiac nociception can also present as angina of cardiac origin. For non-acute coronary syndrome (ACS) stable chest pain, exercise treadmill testing (ETT) remains the primary tool for diagnosis of ischemia and cardiac risk stratification; however, in certain subsets of patients, such as women, ETT has a lower sensitivity and specificity for identifying obstructive CAD. When combined with an imaging modality, such as nuclear perfusion or echocardiography testing, the sensitivity and specificity of stress testing for detection of obstructive CAD improves significantly. Advancements in stress cardiac magnetic resonance imaging (MRI) enables detection of perfusion abnormalities in a specific coronary artery territory, as well as subendocardial ischemia associated with MCD. Coronary computed tomography angiography (CCTA) enables visual assessment of obstructive CAD, albeit with a higher radiation dose. Invasive coronary angiography (CA) remains the gold standard for diagnosis and treatment of obstructive lesions that cause medically refractory stable angina. Furthermore, in patients with normal coronary angiograms, the addition of coronary reactivity testing (CRT) can help diagnose endothelial dependent and independent microvascular dysfunction. Life-style modification and pharmacologic intervention remains the cornerstone of therapy to reduce morbidity and mortality in patients with stable angina. This review focuses on the pathophysiology, diagnosis, and treatment of stable, non-ACS anginal chest pain. PMID:20380951

Feasibilty of a sleep intervention during adjuvant breast cancer chemotherapy.

PubMed

Berger, Ann M; VonEssen, Susanna; Khun, Brett R; Piper, Barbara F; Farr, Lynne; Agrawal, Sangeeta; Lynch, James C; Higginbotham, Patti

2002-01-01

To evaluate the feasibility of an intervention designed to promote sleep and modify fatigue during four cycles of adjuvant breast cancer chemotherapy. Prospective, repeated measures, quasi-experimental feasibility study. Midwestern urban oncology clinics. 25 women between the ages of 40-65 (mean = 54.3) with stage I-II breast cancer receiving doxorubicin-based chemotherapy. Each woman developed, reinforced, and revised an individualized sleep promotion plan (ISPP) with four components: sleep hygiene, relaxation therapy, stimulus control, and sleep restriction techniques. A daily diary, the Pittsburgh Sleep Quality Index, a wrist actigraph, and the Piper Fatigue Scale were used to collect data two days before and seven days after each treatment. Adherence, sleep and wake outcomes, and fatigue. Adherence rates with the components of the ISPP varied during treatments one through four: sleep hygiene (68%-78%), relaxation therapy (57%-67%), stimulus control (46%-67%), and sleep restriction (76%-80%). Mean sleep and wake outcomes at baseline, peak, and rebound times were that (a) sleep latency remained brief (less than 30 minutes per night), (b) time awake after sleep onset exceeded the desired less than 30 minutes per night, (c) sleep efficiency scores remained stable at 85%-90%, (d) total rest time remained stable at 8-10 hours per night, (e) subjective ratings of feelings on arising were stable, and (f) nighttime awakenings were 8-10 per night. Fatigue outcomes were that fatigue was stable two days after each treatment and mean daily fatigue intensity was lower at treatment three than at treatment one but rebounded at treatment four. The intervention was feasible, adherence rates improved over time, and most sleep and wake patterns were consistent with normal values. Revisions will focus on decreasing nighttime awakenings. Adopting behaviors to promote sleep may assist in maintaining sleep and managing fatigue during chemotherapy.

Longitudinal CSF biomarkers in patients with early Parkinson disease and healthy controls

PubMed Central

Caspell-Garcia, Chelsea J.; Coffey, Christopher S.; Taylor, Peggy; Shaw, Leslie M.; Trojanowski, John Q.; Singleton, Andy; Frasier, Mark; Marek, Kenneth; Galasko, Douglas

2017-01-01

Objective: To analyze longitudinal levels of CSF biomarkers in drug-naive patients with Parkinson disease (PD) and healthy controls (HC), examine the extent to which these biomarker changes relate to clinical measures of PD, and identify what may influence them. Methods: CSF α-synuclein (α-syn), total and phosphorylated tau (t- and p-tau), and β-amyloid 1–42 (Aβ42) were measured at baseline and 6 and 12 months in 173 patients with PD and 112 matched HC in the international multicenter Parkinson's Progression Marker Initiative. Baseline clinical and demographic variables, PD medications, neuroimaging, and genetic variables were evaluated as potential predictors of CSF biomarker changes. Results: CSF biomarkers were stable over 6 and 12 months, and there was a small but significant increase in CSF Aβ42 in both patients with patients with PD and HC from baseline to 12 months. The t-tau remained stable. The p-tau increased marginally more in patients with PD than in HC. α-syn remained relatively stable in patients with PD and HC. Ratios of p-tau/t-tau increased, while t-tau/Aβ42 decreased over 12 months in patients with PD. CSF biomarker changes did not correlate with changes in Movement Disorder Society–sponsored revision of the Unified Parkinson’s Disease Rating Scale motor scores or dopamine imaging. CSF α-syn levels at 12 months were lower in patients with PD treated with dopamine replacement therapy, especially dopamine agonists. Conclusions: These core CSF biomarkers remained stable over 6 and 12 months in patients with early PD and HC. PD medication use may influence CSF α-syn. Novel biomarkers are needed to better profile progressive neurodegeneration in PD. PMID:29030452

Nicotine dependence and transitional shifts in exercise behavior among young U.S. adult smokers.

PubMed

Loprinzi, Paul D; Walker, Jerome F; Cardinal, Bradley J

2014-08-01

The aim of this study is to examine the association between nicotine dependence and longitudinal exercise transitional shift patterns among young U.S. adult daily smokers. Data from the 2003-2005 National Youth Smoking Cessation Survey was used, which is a longitudinal study over a two year period. Participants included 1168 US adult daily smokers (18-24years). Nicotine dependence was assessed using the modified Fagerstrom Test for Nicotine Dependence. Four transitional shift patterns were created based on meeting current exercise guidelines; stable inactive (inactive across time), activity relapsers (starts out active and then becomes inactive), activity adopters (inactive and then becomes active), and stable active (active across time). After adjustments, for every 1-unit increase in baseline nicotine dependence, participants had 16% (OR=1.16, p=0.01) greater odds of being in the stable inactive group compared to the stable active group. Nicotine dependence appears to play an important role in shaping longitudinal exercise patterns among young U.S. adult smokers. Copyright © 2014 Elsevier Inc. All rights reserved.

One-dimensional CuIn alloy nanowires as a robust and efficient electrocatalyst for selective CO2-to-CO conversion

NASA Astrophysics Data System (ADS)

Jang, Youn Jeong; Lee, Jaehyuk; Kim, Ju Hun; Lee, Byeong Jun; Lee, Jae Sung

2018-02-01

Electrical anodization of Cu foil produces one-dimensional Cu nanowires of high surface areas, which turns to CuIn alloy nanowires by indium electrodeposition replacing edge site Cu atoms. An electrochemical pre-activation forms a highly conformal amorphous In(OH)3 overlayer with oxygen vacancy on the CuIn alloy that facilitates CO2 adsorption to promote selective CO formation suppressing competing H2 adsorption. Thus the activated CuIn alloy nanowires catalyse electrochemical CO2 conversion to CO with high CO selectivity (>68.2%) and high current density (ca. -3.9 mAcm-2) at -0.6 VRHE, which represents the higher partial CO current density (ca. -2.66 mAcm-2) than that of previously reported CuIn alloy powders without nanostructuring. The performance remains stable for more than 15 h without significant degradation.

Domains and Determinants of Well-Being of Older Adults in India.

PubMed

Ladusingh, Laishram; Ngangbam, Sapana

2016-03-01

This study proposes a well-being index of older adults which integrates five domains, namely, activities of daily living, health status, psychological strength, life accomplishment and social ties, and examines potential socio-demographic, living arrangement, lifestyle and religiosity determinants of well-being. The present study uses micro data of 1255 older adults from the recent pilot survey for the Longitudinal Aging Study in India (LASI) conducted in 2010. The results suggest that normal activities of daily life, health, and social ties decline with advancing age, while life accomplishment remains stable over age. However, when all domains are integrated, well-being tends to fade out with advancing age. While smoking has a deterrent effect on well-being, better economic status, literacy, living in a joint family with spouse, religiosity, and regular physical exercise have a statistically significant positive effect on the well-being of older adults in India.

Eliminating Voltage Decay of Lithium-Rich Li 1.14Mn 0.54Ni 0.14Co 0.14O 2 Cathodes by Controlling the Electrochemical Process

DOE PAGES

Wei, Z.; Zhu, Y.; Zhang, W.; ...

2015-03-27

Lithium-rich material owns a particularly high capacity owing to the activation of electrochemical inactive Li 2MnO 3 phase. But at the same time, MnO 2 phase formed after Li 2MnO 3 activation confronts a severe problem of converting to spinel phase, and resulting in voltage decay. To our knowledge, this phenomenon is inherent property of layered manganese oxide materials and can hardly be overcome. Based on this, unlike previous reports, herein we design a method for the first time to accelerate the phase transformation by tuning the charge upper-limit voltage at a high value, so the phase transformation process canmore » be finished in a few cycles. Then material structure remains stable while cycling at a low upper-limit voltage. By this novel method voltage decay is eliminated significantly.« less

Active mode locking of quantum cascade lasers in an external ring cavity.

PubMed

Revin, D G; Hemingway, M; Wang, Y; Cockburn, J W; Belyanin, A

2016-05-05

Stable ultrashort light pulses and frequency combs generated by mode-locked lasers have many important applications including high-resolution spectroscopy, fast chemical detection and identification, studies of ultrafast processes, and laser metrology. While compact mode-locked lasers emitting in the visible and near infrared range have revolutionized photonic technologies, the systems operating in the mid-infrared range where most gases have their strong absorption lines, are bulky and expensive and rely on nonlinear frequency down-conversion. Quantum cascade lasers are the most powerful and versatile compact light sources in the mid-infrared range, yet achieving their mode-locked operation remains a challenge, despite dedicated effort. Here we report the demonstration of active mode locking of an external-cavity quantum cascade laser. The laser operates in the mode-locked regime at room temperature and over the full dynamic range of injection currents.

Active mode locking of quantum cascade lasers in an external ring cavity

PubMed Central

Revin, D. G.; Hemingway, M.; Wang, Y.; Cockburn, J. W.; Belyanin, A.

2016-01-01

Stable ultrashort light pulses and frequency combs generated by mode-locked lasers have many important applications including high-resolution spectroscopy, fast chemical detection and identification, studies of ultrafast processes, and laser metrology. While compact mode-locked lasers emitting in the visible and near infrared range have revolutionized photonic technologies, the systems operating in the mid-infrared range where most gases have their strong absorption lines, are bulky and expensive and rely on nonlinear frequency down-conversion. Quantum cascade lasers are the most powerful and versatile compact light sources in the mid-infrared range, yet achieving their mode-locked operation remains a challenge, despite dedicated effort. Here we report the demonstration of active mode locking of an external-cavity quantum cascade laser. The laser operates in the mode-locked regime at room temperature and over the full dynamic range of injection currents. PMID:27147409

Using Virtual Reality to Dynamically Setting an Electrical Wheelchair

NASA Astrophysics Data System (ADS)

Dir, S.; Habert, O.; Pruski, A.

2008-06-01

This work uses virtual reality to find or refine in a recurring way the best adequacy between a person with physically disability and his electrical wheelchair. A system architecture based on "Experiment→Analyze and decision-making→Modification of the wheelchair" cycles is proposed. This architecture uses a decision-making module based on a fuzzy inference system which has to be parameterized so that the system converges quickly towards the optimal solution. The first challenge consists in computing criteria which must represent as well as possible particular situations that the user meets during each navigation experiment. The second challenge consists in transforming these criteria into relevant modifications about the active or non active functionalities or into adjustment of intrinsic setting of the wheelchair. These modifications must remain most stable as possible during the successive experiments. Objectives are to find the best wheelchair to give a beginning of mobility to a given person with physically disability.

The recovery paradigm - a model of hope and change for alcohol and drug addiction.

PubMed

Best, David W; Lubman, Dan I

2012-08-01

Alcohol and drug disorders remain major health and social problems in Australia, contributing enormously to the global burden of disease and the everyday practice of primary care. A recent growth in recovery research and recovery focused policies are starting to have an impact in Australia, with implications for how we attempt to resolve these problems. In this article we discuss recent international findings in recovery research, and explore their implications for primary care. Research indicates that over half of dependent substance users will eventually achieve stable recovery. Key predictors of recovery are active engagement in the community and immersion in peer support groups and activities. Recovery requires a twin track approach: enabling and supporting individual recovery journeys, while creating environmental conditions that enable and support a 'social contagion' of recovery, in which recovery is transmitted through supportive social networks and dedicated recovery groups, such as mutual aid.

[Facilitation of a state of wakefulness by semi-chronic treatment with sulbutiamin (Arcalion) in Macaca mulatta].

PubMed

Balzamo, E; Vuillon-Cacciuttolo, G

1982-12-01

Cortical electroencephalographic (EEG) activities and nycthemeral states of vigilance organization were studied in 6 adult rhesus monkeys during subchronic administration (10 days) of Sulbutiamin, a synthesized derivative of thiamine (300 mg/kg/day). Sulbutiamin induced the following modifications: (1) In the EEG activities: increase in occurrence of fast rhythms (over 28 c/sec) during waking and also during slow sleep (SS) in which their amplitude doubled. SS spindles increased in number and amplitude. (2) In vigilance organization: waking was enhanced all along the 24 h recording and SS was reorganized (particularly at night), mostly light sleep: large decrease in stage 2 duration, increase in stage 1. REM sleep duration remained stable. These changes, occurring at around day 5 of the treatment, were more pronounced on day 10 and disappeared 2-5 days after withdrawal. This study demonstrated the clear action of Sulbutiamin upon the mechanisms regulating waking and light sleep.

Biogenic silver and gold nanoparticles synthesized using red ginseng root extract, and their applications.

PubMed

Singh, Priyanka; Kim, Yeon Ju; Wang, Chao; Mathiyalagan, Ramya; El-Agamy Farh, Mohamed; Yang, Deok Chun

2016-05-01

In the present study, we report a green methodology for the synthesis of silver and gold nanoparticles, using the root extract of the herbal medicinal plant Korean red ginseng. The silver and gold nanoparticles were synthesized within 1 h and 10 min respectively. The nanoparticles generated were not aggregated, and remained stable for a long time, which suggests the nature of nanoparticles. The phytochemicals and ginsenosides present in the root extract assist in reducing and stabilizing the synthesized nanoparticles. The red ginseng root extract-generated silver nanoparticles exhibit antimicrobial activity against pathogenic microorganisms including Vibrio parahaemolyticus, Staphylococcus aureus, Bacillus cereus, and Candida albicans. In addition, the silver nanoparticles exhibit biofilm degrading activity against S. aureus and Pseudomonas aeruginosa. Thus, the present study opens up a new possibility of synthesizing silver and gold nanoparticles in a green and rapid manner using Korean red ginseng root extract, and explores their biomedical applications.

Association of Longitudinal Changes of Physical Activity on Smoking Cessation Among Young Daily Smokers.

PubMed

Loprinzi, Paul D; Walker, Jerome F

2016-01-01

To our knowledge, no longitudinal epidemiological study among daily smokers has examined the effects of physical activity change/ trajectory on smoking cessation. The purpose of this study was to examine the longitudinal effects of changes in physical activity on smoking cessation among a national sample of young (16-24 y) daily smokers. Data from the 2003-2005 National Youth Smoking Cessation Survey were used (N = 1178). Using hierarchical agglomerative cluster analysis, 5 distinct self-reported physical activity trajectories over 3 time periods (baseline, 12-month, and 24-month follow-up) were observed, including stable low physical activity, decreasing physical activity, curvilinear physical activity, stable high physical activity, and increasing physical activity. Nicotine dependence (Heaviness of Smoking Index) and demographic parameters were assessed via survey. With stable low physical activity (16.2% quit smoking) serving as the referent group, those in the stable high physical activity (24.8% quit smoking) group had 1.8 greater odds of not smoking at the 24-month follow-up period (odds ratio = 1.81; 95% confidence interval, 1.12-2.91) after adjusting for nicotine dependence, age, gender, race-ethnicity, and education. Maintenance of regular physical activity among young daily smokers may help to facilitate smoking cessation.

Real-world glycemic, blood pressure, and weight control in patients with type 2 diabetes mellitus treated with canagliflozin-an electronic health-record-based study.

PubMed

Lefebvre, Patrick; Pilon, Dominic; Robitaille, Marie-Noëlle; Lafeuille, Marie-Hélène; Chow, Wing; Pfeifer, Michael; Duh, Mei Sheng

2016-06-01

Canagliflozin (CANA) has been shown to improve HbA1c, blood pressure (BP), and weight in patients with type 2 diabetes mellitus (T2DM) in clinical trials. This study describes HbA1c, BP, and weight in T2DM patients treated with CANA in a real-world setting. Adults with ≥1 diagnosis for T2DM and ≥12 months of clinical activity before the first CANA prescription (index) were identified in the IMS Health Real-World Data Electronic Medical Records - US database. Patient quality measures were described at baseline and 3, 6, 9, and 12 months post-index. Selected goals were HbA1c <7% (<53 mmol/mol), <8% (<64 mmol/mol), and >9% (>75 mmol/mol, poor control), BP <140/90 mmHg, and weight loss ≥5%. In total, 16,163 patients were identified (mean age = 58.5 years; 47.9% female; 75.8% white). At baseline, 90.4% of patients used ≥1 anti-hyperglycemic agent. Among patients with baseline HbA1c ≥7% (n = 10,478; 64.8%; mean HbA1c = 8.8%), 21.2%, 59.5%, and 17.6% had an HbA1c <7%, <8%, and >9% after 3 months, respectively; these proportions remained stable through 12 months. Among patients with baseline BP ≥140/90, 60.0% and 75.6% attained systolic BP <140 mmHg and diastolic BP <90 mmHg after 3 months, respectively; proportions remained stable through 12 months. Weight loss ≥5% was observed in 13.3% of patients at 3 months and the proportion increased to 25.8% at 12 months. This study relied on prescription data, which does not necessarily indicate that the medication was taken as prescribed. Some patients were also treated with other anti-hyperglycemics, anti-hypertensives, and weight loss medications during the follow-up, which may have contributed to the effects reported. Most patients with inadequate HbA1c and BP levels at baseline achieved respective goals after 3 months of CANA, and the proportions of responders remained stable through 12 months. Weight loss ≥5% was increasingly observed over time.

Evaluating the Tongue-Hold Maneuver Using High-Resolution Manometry and Electromyography

PubMed Central

Hammer, Michael J.; Jones, Corinne A.; Mielens, Jason D.; Kim, Chloe H.; McCulloch, Timothy M.

2014-01-01

The tongue-hold maneuver is a widely used clinical technique designed to increase posterior pharyngeal wall movement in individuals with dysphagia. It is hypothesized that the tongue-hold maneuver results in increased contraction of the superior pharyngeal constrictor. However, an electromyographic study of the pharynx and tongue during the tongue-hold is still needed to understand whether and how swallow muscle activity and pressure may change with this maneuver. We tested eight healthy young participants using simultaneous intramuscular electromyography with high-resolution manometry during three task conditions including (a) saliva swallow without maneuver, (b) saliva swallow with the tongue tip at the lip, and (c) saliva swallow during the tongue-hold maneuver. We tested the hypothesis that tongue and pharyngeal muscle activity would increase during the experimental tasks, but that pharyngeal pressure would remain relatively unchanged. We found that the pre-swallow magnitude of tongue, pharyngeal constrictor, and cricopharyngeus muscle activity increased. During the swallow, the magnitude and duration of tongue and pharyngeal constrictor muscle activity each increased. However, manometric pressures and durations remained unchanged. These results suggest that increased superior pharyngeal constrictor activity may serve to maintain relatively stable pharyngeal pressures in the absence of posterior tongue movement. Thus, the tongue-hold maneuver may be a relatively simple but robust example of how the medullary swallow center is equipped to dynamically coordinate actions between tongue and pharynx. Our findings emphasize the need for combined modality swallow assessment to include high-resolution manometry and intramuscular electromyography to evaluate the potential benefit of the tongue-hold maneuver for clinical populations. PMID:24969727

Effects of phosphate binders in moderate CKD.

PubMed

Block, Geoffrey A; Wheeler, David C; Persky, Martha S; Kestenbaum, Bryan; Ketteler, Markus; Spiegel, David M; Allison, Matthew A; Asplin, John; Smits, Gerard; Hoofnagle, Andrew N; Kooienga, Laura; Thadhani, Ravi; Mannstadt, Michael; Wolf, Myles; Chertow, Glenn M

2012-08-01

Some propose using phosphate binders in the CKD population given the association between higher levels of phosphorus and mortality, but their safety and efficacy in this population are not well understood. Here, we aimed to determine the effects of phosphate binders on parameters of mineral metabolism and vascular calcification among patients with moderate to advanced CKD. We randomly assigned 148 patients with estimated GFR=20-45 ml/min per 1.73 m(2) to calcium acetate, lanthanum carbonate, sevelamer carbonate, or placebo. The primary endpoint was change in mean serum phosphorus from baseline to the average of months 3, 6, and 9. Serum phosphorus decreased from a baseline mean of 4.2 mg/dl in both active and placebo arms to 3.9 mg/dl with active therapy and 4.1 mg/dl with placebo (P=0.03). Phosphate binders, but not placebo, decreased mean 24-hour urine phosphorus by 22%. Median serum intact parathyroid hormone remained stable with active therapy and increased with placebo (P=0.002). Active therapy did not significantly affect plasma C-terminal fibroblast growth factor 23 levels. Active therapy did, however, significantly increase calcification of the coronary arteries and abdominal aorta (coronary: median increases of 18.1% versus 0.6%, P=0.05; abdominal aorta: median increases of 15.4% versus 3.4%, P=0.03). In conclusion, phosphate binders significantly lower serum and urinary phosphorus and attenuate progression of secondary hyperparathyroidism among patients with CKD who have normal or near-normal levels of serum phosphorus; however, they also promote the progression of vascular calcification. The safety and efficacy of phosphate binders in CKD remain uncertain.

Stability and Longevity in the Publication Careers of U.S. Doctorate Recipients

PubMed Central

Waaijer, Cathelijn J. F.; Macaluso, Benoît; Sugimoto, Cassidy R.; Larivière, Vincent

2016-01-01

Since the 1950s, the number of doctorate recipients has risen dramatically in the United States. In this paper, we investigate whether the longevity of doctorate recipients’ publication careers has changed. This is achieved by matching 1951–2010 doctorate recipients with rare names in astrophysics, chemistry, economics, genetics and psychology in the dissertation database ProQuest to their publications in the publication database Web of Science. Our study shows that pre-PhD publication careers have changed: the median year of first publication has shifted from after the PhD to several years before PhD in most of the studied fields. In contrast, post-PhD publication career spans have not changed much in most fields. The share of doctorate recipients who have published for more than twenty years has remained stable over time; the shares of doctorate recipients publishing for shorter periods also remained almost unchanged. Thus, though there have been changes in pre-PhD publication careers, post-PhD career spans remained quite stable. PMID:27128633

The role of total elbow arthroplasty in traumatology.

PubMed

Mansat, P; Bonnevialle, N; Rongières, M; Bonnevialle, P

2014-10-01

Fractures of the distal humerus account for 5% of osteoporotic fractures in subjects older than 60 years. A history of osteoporosis, co-morbidities, and joint comminution make their management difficult. The therapeutic options are limited to functional treatments, osteosynthesis, or either partial or total arthroplasty. Functional treatment of distal humerus fractures in the elderly subject provide inconsistent results, often with persistence of pain with a stiff or unstable elbow. Osteosynthesis remains the reference treatment for these fractures, following the principle of stable and rigid osteosynthesis allowing early mobilization. However, joint comminution and a history of osteoporosis occasionally make it impossible to meet this objective, with a considerable rate of complications and surgical revisions. Total elbow arthroplasty remains an alternative to osteosynthesis with very satisfactory immediate results restoring a painless, stable, and functional elbow. These results seem reproducible and sustainable over time. The complication rate is not uncommon with an approximately 10% surgical revision rate. Elbow hemiarthroplasty remains to be validated in this indication. V. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

The causal role of breakfast in energy balance and health: a randomized controlled trial in lean adults.

PubMed

Betts, James A; Richardson, Judith D; Chowdhury, Enhad A; Holman, Geoffrey D; Tsintzas, Kostas; Thompson, Dylan

2014-08-01

Popular beliefs that breakfast is the most important meal of the day are grounded in cross-sectional observations that link breakfast to health, the causal nature of which remains to be explored under real-life conditions. The aim was to conduct a randomized controlled trial examining causal links between breakfast habits and all components of energy balance in free-living humans. The Bath Breakfast Project is a randomized controlled trial with repeated-measures at baseline and follow-up in a cohort in southwest England aged 21-60 y with dual-energy X-ray absorptiometry-derived fat mass indexes ≤11 kg/m² in women (n = 21) and ≤7.5 kg/m² in men (n = 12). Components of energy balance (resting metabolic rate, physical activity thermogenesis, energy intake) and 24-h glycemic responses were measured under free-living conditions with random allocation to daily breakfast (≥700 kcal before 1100) or extended fasting (0 kcal until 1200) for 6 wk, with baseline and follow-up measures of health markers (eg, hematology/biopsies). Contrary to popular belief, there was no metabolic adaptation to breakfast (eg, resting metabolic rate stable within 11 kcal/d), with limited subsequent suppression of appetite (energy intake remained 539 kcal/d greater than after fasting; 95% CI: 157, 920 kcal/d). Rather, physical activity thermogenesis was markedly higher with breakfast than with fasting (442 kcal/d; 95% CI: 34, 851 kcal/d). Body mass and adiposity did not differ between treatments at baseline or follow-up and neither did adipose tissue glucose uptake or systemic indexes of cardiovascular health. Continuously measured glycemia was more variable during the afternoon and evening with fasting than with breakfast by the final week of the intervention (CV: 3.9%; 95% CI: 0.1%, 7.8%). Daily breakfast is causally linked to higher physical activity thermogenesis in lean adults, with greater overall dietary energy intake but no change in resting metabolism. Cardiovascular health indexes were unaffected by either of the treatments, but breakfast maintained more stable afternoon and evening glycemia than did fasting.

Gut memories do not fade: epigenetic regulation of lasting gut homing receptor expression in CD4+ memory T cells.

PubMed

Szilagyi, B A; Triebus, J; Kressler, C; de Almeida, M; Tierling, S; Durek, P; Mardahl, M; Szilagyi, A; Floess, S; Huehn, J; Syrbe, U; Walter, J; Polansky, J K; Hamann, A

2017-11-01

The concept of a "topographical memory" in lymphocytes implies a stable expression of homing receptors mediating trafficking of lymphocytes back to the tissue of initial activation. However, a significant plasticity of the gut-homing receptor α 4 β 7 was found in CD8 + T cells, questioning the concept. We now demonstrate that α 4 β 7 expression in murine CD4 + memory T cells is, in contrast, imprinted and remains stable in the absence of the inducing factor retinoic acid (RA) or other stimuli from mucosal environments. Repetitive rounds of RA treatment enhanced the stability of de novo induced α 4 β 7 . A novel enhancer element in the murine Itga4 locus was identified that showed, correlating to stability, selective DNA demethylation in mucosa-seeking memory cells and methylation-dependent transcriptional activity in a reporter gene assay. This implies that epigenetic mechanisms contribute to the stabilization of α 4 β 7 expression. Analogous DNA methylation patterns could be observed in the human ITGA4 locus, suggesting that its epigenetic regulation is conserved between mice and men. These data prove that mucosa-specific homing mediated by α 4 β 7 is imprinted in CD4 + memory T cells, reinstating the validity of the concept of "topographical memory" for mucosal tissues, and imply a critical role of epigenetic mechanisms.

High copy and stable expression of the xylanase XynHB in Saccharomyces cerevisiae by rDNA-mediated integration.

PubMed

Fang, Cheng; Wang, Qinhong; Selvaraj, Jonathan Nimal; Zhou, Yuling; Ma, Lixin; Zhang, Guimin; Ma, Yanhe

2017-08-18

Xylanase is a widely-used additive in baking industry for enhancing dough and bread quality. Several xylanases used in baking industry were expressed in different systems, but their expression in antibiotic free vector system is highly essential and safe. In the present study, an alternative rDNA-mediated technology was developed to increase the copy number of target gene by integrating it into Saccharomyces cerevisiae genome. A xylanase-encoding gene xynHB from Bacillus sp. was cloned into pHBM367H and integrated into S. cerevisiae genome through rDNA-mediated recombination. Exogenous XynHB expressed by recombinant S. cerevisiae strain A13 exhibited higher degradation activity towards xylan than other transformants. The real-time PCR analysis on A13 genome revealed the presence of 13.64 copies of xynHB gene. Though no antibiotics have been used, the genetic stability and the xylanase activity of xynHB remained stable up to 1,011 generations of cultivation. S. cerevisiae strain A13 expressing xylanase reduced the required kneading time and increased the height and diameter of the dough size, which would be safe and effective in baking industry as no antibiotics-resistance risk. The new effective rDNA-mediated technology without using antibiotics here provides a way to clone other food related industrial enzymes for applications.

Evidence of Influence of Human Activities and Volcanic Eruptions on Environmental Perchlorate from a 300-Year Greenland Ice Core Record.

PubMed

Cole-Dai, Jihong; Peterson, Kari Marie; Kennedy, Joshua Andrew; Cox, Thomas S; Ferris, David G

2018-06-26

A 300-year (1700-2007) chronological record of environmental perchlorate, reconstructed from high-resolution analysis of a central Greenland ice core, shows that perchlorate levels in the post-1980 atmosphere were two-to-three times those of the pre-1980 environment. While this confirms recent reports of increased perchlorate in Arctic snow since 1980 compared with the levels for the prior decades (1930-1980), the longer Greenland record demonstrates that the Industrial Revolution and other human activities, which emitted large quantities of pollutants and contaminants, did not significantly impact environmental perchlorate, as perchlorate levels remained stable throughout the eighteenth, nineteenth, and much of the twentieth centuries. The increased levels since 1980 likely result from enhanced atmospheric perchlorate production, rather than from direct release from perchlorate manufacturing and applications. The enhancement is probably influenced by the emission of organic chlorine compounds in the last several decades. Prior to 1980, no significant long-term temporal trends in perchlorate concentration are observed. Brief (a few years) high concentration episodes appear frequently over an apparently stable and low background (~1 ng kg‒1). Several such episodes coincide in time with large explosive volcanic eruptions including the 1912 Novarupta/Katmai eruption in Alaska. It appears that atmospheric perchlorate production is impacted by large eruptions in both high and low latitudes, but not by small eruptions and non-explosive degassing.

Evaluation of autotrophic growth of ammonia-oxidizers associated with granular activated carbon used for drinking water purification by DNA-stable isotope probing.

PubMed

Niu, Jia; Kasuga, Ikuro; Kurisu, Futoshi; Furumai, Hiroaki; Shigeeda, Takaaki

2013-12-01

Nitrification is an important biological function of granular activated carbon (GAC) used in advanced drinking water purification processes. Newly discovered ammonia-oxidizing archaea (AOA) have challenged the traditional understanding of ammonia oxidation, which considered ammonia-oxidizing bacteria (AOB) as the sole ammonia-oxidizers. Previous studies demonstrated the predominance of AOA on GAC, but the contributions of AOA and AOB to ammonia oxidation remain unclear. In the present study, DNA-stable isotope probing (DNA-SIP) was used to investigate the autotrophic growth of AOA and AOB associated with GAC at two different ammonium concentrations (0.14 mg N/L and 1.4 mg N/L). GAC samples collected from three full-scale drinking water purification plants in Tokyo, Japan, had different abundance of AOA and AOB. These samples were fed continuously with ammonium and (13)C-bicarbonate for 14 days. The DNA-SIP analysis demonstrated that only AOA assimilated (13)C-bicarbonate at low ammonium concentration, whereas AOA and AOB exhibited autotrophic growth at high ammonium concentration. This indicates that a lower ammonium concentration is preferable for AOA growth. Since AOA could not grow without ammonium, their autotrophic growth was coupled with ammonia oxidation. Overall, our results point towards an important role of AOA in nitrification in GAC filters treating low concentration of ammonium. Copyright © 2013 Elsevier Ltd. All rights reserved.

Towards highly stable polymer electronics (Conference Presentation)

NASA Astrophysics Data System (ADS)

Nikolka, Mark; Nasrallah, Iyad; Broch, Katharina; Sadhanala, Aditya; Hurhangee, Michael; McCulloch, Iain; Sirringhaus, Henning

2016-11-01

Due to their ease of processing, organic semiconductors are promising candidates for applications in high performance flexible displays and fast organic electronic circuitry. Recently, a lot of advances have been made on organic semiconductors exhibiting surprisingly high performance and carrier mobilities exceeding those of amorphous silicon. However, there remain significant concerns about their operational and environmental stability, particularly in the context of applications that require a very high level of threshold voltage stability, such as active-matrix addressing of organic light-emitting diode (OLED) displays. Here, we report a novel technique for dramatically improving the operational stress stability, performance and uniformity of high mobility polymer field-effect transistors by the addition of specific small molecule additives to the polymer semiconductor film. We demonstrate for the first time polymer FETs that exhibit stable threshold voltages with threshold voltage shifts of less than 1V when subjected to a constant current operational stress for 1 day under conditions that are representative for applications in OLED active matrix displays. The approach constitutes in our view a technological breakthrough; it also makes the device characteristics independent of the atmosphere in which it is operated, causes a significant reduction in contact resistance and significantly improves device uniformity. We will discuss in detail the microscopic mechanism by which the molecular additives lead to this significant improvement in device performance and stability.

Low-Temperature (10°C) Anaerobic Digestion of Dilute Dairy Wastewater in an EGSB Bioreactor: Microbial Community Structure, Population Dynamics, and Kinetics of Methanogenic Populations

PubMed Central

Cysneiros, Denise; O'Flaherty, Vincent

2013-01-01

The feasibility of anaerobic digestion of dairy wastewater at 10°C was investigated in a high height : diameter ratio EGSB reactor. Stable performance was observed at an applied organic loading rate (OLR) of 0.5–2 kg COD m−3 d−1 with chemical oxygen demand (COD) removal efficiencies above 85%. When applied OLR increased to values above 2 kg COD m−3 d−1, biotreatment efficiency deteriorated, with methanogenesis being the rate-limiting step. The bioreactor recovered quickly (3 days) after reduction of the OLR. qPCR results showed a reduction in the abundance of hydrogenotrophic methanogenic Methanomicrobiales and Methanobacteriales throughout the steady state period followed by a sharp increase in their numbers (111-fold) after the load shock. Specific methanogenic activity and maximum substrate utilising rate (A max) of the biomass at the end of trial indicated increased activity and preference towards hydrogenotrophic methanogenesis, which correlated well with the increased abundance of hydrogenotrophic methanogens. Acetoclastic Methanosaeta spp. remained at stable levels throughout the trial. However, increased apparent half-saturation constant (K m) at the end of the trial indicated a decrease in the specific substrate affinity for acetate of the sludge, suggesting that Methanosaeta spp., which have high substrate affinity, started to be outcompeted in the reactor. PMID:24089597

Low-temperature (10°C) anaerobic digestion of dilute dairy wastewater in an EGSB bioreactor: microbial community structure, population dynamics, and kinetics of methanogenic populations.

PubMed

Bialek, Katarzyna; Cysneiros, Denise; O'Flaherty, Vincent

2013-01-01

The feasibility of anaerobic digestion of dairy wastewater at 10°C was investigated in a high height : diameter ratio EGSB reactor. Stable performance was observed at an applied organic loading rate (OLR) of 0.5-2 kg COD m(-3) d(-1) with chemical oxygen demand (COD) removal efficiencies above 85%. When applied OLR increased to values above 2 kg COD m(-3) d(-1), biotreatment efficiency deteriorated, with methanogenesis being the rate-limiting step. The bioreactor recovered quickly (3 days) after reduction of the OLR. qPCR results showed a reduction in the abundance of hydrogenotrophic methanogenic Methanomicrobiales and Methanobacteriales throughout the steady state period followed by a sharp increase in their numbers (111-fold) after the load shock. Specific methanogenic activity and maximum substrate utilising rate (A(max)) of the biomass at the end of trial indicated increased activity and preference towards hydrogenotrophic methanogenesis, which correlated well with the increased abundance of hydrogenotrophic methanogens. Acetoclastic Methanosaeta spp. remained at stable levels throughout the trial. However, increased apparent half-saturation constant (K(m)) at the end of the trial indicated a decrease in the specific substrate affinity for acetate of the sludge, suggesting that Methanosaeta spp., which have high substrate affinity, started to be outcompeted in the reactor.

Revisions to some parameters used in stochastic-method simulations of ground motion

USGS Publications Warehouse

Boore, David; Thompson, Eric M.

2015-01-01

The stochastic method of ground‐motion simulation specifies the amplitude spectrum as a function of magnitude (M) and distance (R). The manner in which the amplitude spectrum varies with M and R depends on physical‐based parameters that are often constrained by recorded motions for a particular region (e.g., stress parameter, geometrical spreading, quality factor, and crustal amplifications), which we refer to as the seismological model. The remaining ingredient for the stochastic method is the ground‐motion duration. Although the duration obviously affects the character of the ground motion in the time domain, it also significantly affects the response of a single‐degree‐of‐freedom oscillator. Recently published updates to the stochastic method include a new generalized double‐corner‐frequency source model, a new finite‐fault correction, a new parameterization of duration, and a new duration model for active crustal regions. In this article, we augment these updates with a new crustal amplification model and a new duration model for stable continental regions. Random‐vibration theory (RVT) provides a computationally efficient method to compute the peak oscillator response directly from the ground‐motion amplitude spectrum and duration. Because the correction factor used to account for the nonstationarity of the ground motion depends on the ground‐motion amplitude spectrum and duration, we also present new RVT correction factors for both active and stable regions.

Cerebral vascular structure in the motor cortex of adult mice is stable and is not altered by voluntary exercise.

PubMed

Cudmore, Robert H; Dougherty, Sarah E; Linden, David J

2017-12-01

The cerebral vasculature provides blood flow throughout the brain, and local changes in blood flow are regulated to match the metabolic demands of the active brain regions. This neurovascular coupling is mediated by real-time changes in vessel diameter and depends on the underlying vascular network structure. Neurovascular structure is configured during development by genetic and activity-dependent factors. In adulthood, it can be altered by experiences such as prolonged hypoxia, sensory deprivation and seizure. Here, we have sought to determine whether exercise could alter cerebral vascular structure in the adult mouse. We performed repeated in vivo two-photon imaging in the motor cortex of adult transgenic mice expressing membrane-anchored green fluorescent protein in endothelial cells (tyrosine endothelial kinase 2 receptor (Tie2)-Cre:mTmG). This strategy allows for high-resolution imaging of the vessel walls throughout the lifespan. Vascular structure, as measured by capillary branch point number and position, segment diameter and length remained stable over a time scale of months as did pericyte number and position. Furthermore, we compared the vascular structure before, during, and after periods of voluntary wheel running and found no alterations in these same parameters. In both running and control mice, we observed a low rate of capillary segment subtraction. Interestingly, these rare subtraction events preferentially remove short vascular loops.

Linear stable unity-feedback system - Necessary and sufficient conditions for stability under nonlinear plant perturbations

NASA Technical Reports Server (NTRS)

Desoer, C. A.; Kabuli, M. G.

1989-01-01

The authors consider a linear (not necessarily time-invariant) stable unity-feedback system, where the plant and the compensator have normalized right-coprime factorizations. They study two cases of nonlinear plant perturbations (additive and feedback), with four subcases resulting from: (1) allowing exogenous input to Delta P or not; 2) allowing the observation of the output of Delta P or not. The plant perturbation Delta P is not required to be stable. Using the factorization approach, the authors obtain necessary and sufficient conditions for all cases in terms of two pairs of nonlinear pseudostate maps. Simple physical considerations explain the form of these necessary and sufficient conditions. Finally, the authors obtain the characterization of all perturbations Delta P for which the perturbed system remains stable.

Endemism hotspots are linked to stable climatic refugia

PubMed Central

Noss, Reed

2017-01-01

Background Centres of endemism have received much attention from evolutionists, biogeographers, ecologists and conservationists. Climatic stability is often cited as a major reason for the occurrences of these geographic concentrations of species which are not found anywhere else. The proposed linkage between endemism and climatic stability raises unanswered questions about the persistence of biodiversity during the present era of rapidly changing climate. Key Questions The current status of evidence linking geographic centres of endemism to climatic stability over evolutionary time was examined. The following questions were asked. Do macroecological analyses support such an endemism–stability linkage? Do comparative studies find that endemic species display traits reflecting evolution in stable climates? Will centres of endemism in microrefugia or macrorefugia remain relatively stable and capable of supporting high biological diversity into the future? What are the implications of the endemism–stability linkage for conservation? Conclusions Recent work using the concept of climate change velocity supports the classic idea that centres of endemism occur where past climatic fluctuations have been mild and where mountainous topography or favourable ocean currents contribute to creating refugia. Our knowledge of trait differences between narrow endemics and more widely distributed species remains highly incomplete. Current knowledge suggests that centres of endemism will remain relatively climatically buffered in the future, with the important caveat that absolute levels of climatic change and species losses in these regions may still be large. PMID:28064195

Conformational Flexibility of a Short Loop near the Active Site of the SARS-3CLpro is Essential to Maintain Catalytic Activity

NASA Astrophysics Data System (ADS)

Li, Chunmei; Teng, Xin; Qi, Yifei; Tang, Bo; Shi, Hailing; Ma, Xiaomin; Lai, Luhua

2016-02-01

The SARS 3C-like proteinase (SARS-3CLpro), which is the main proteinase of the SARS coronavirus, is essential to the virus life cycle. This enzyme has been shown to be active as a dimer in which only one protomer is active. However, it remains unknown how the dimer structure maintains an active monomer conformation. It has been observed that the Ser139-Leu141 loop forms a short 310-helix that disrupts the catalytic machinery in the inactive monomer structure. We have tried to disrupt this helical conformation by mutating L141 to T in the stable inactive monomer G11A/R298A/Q299A. The resulting tetra-mutant G11A/L141T/R298A/Q299A is indeed enzymatically active as a monomer. Molecular dynamics simulations revealed that the L141T mutation disrupts the 310-helix and helps to stabilize the active conformation. The coil-310-helix conformational transition of the Ser139-Leu141 loop serves as an enzyme activity switch. Our study therefore indicates that the dimer structure can stabilize the active conformation but is not a required structure in the evolution of the active enzyme, which can also arise through simple mutations.

Caseinolytic and milk-clotting activities from Moringa oleifera flowers.

PubMed

Pontual, Emmanuel V; Carvalho, Belany E A; Bezerra, Ranilson S; Coelho, Luana C B B; Napoleão, Thiago H; Paiva, Patrícia M G

2012-12-01

This work reports the detection and characterization of caseinolytic and milk-clotting activities from Moringa oleifera flowers. Proteins extracted from flowers were precipitated with 60% ammonium sulphate. Caseinolytic activity of the precipitated protein fraction (PP) was assessed using azocasein, as well as α(s)-, β- and κ-caseins as substrates. Milk-clotting activity was analysed using skim milk. The effects of heating (30-100°C) and pH (3.0-11.0) on enzyme activities were determined. Highest caseinolytic activity on azocasein was detected after previous incubation of PP at pH 4.0 and after heating at 50°C. Milk-clotting activity, detected only in the presence of CaCl(2), was highest at incubation of PP at pH 3.0 and remained stable up to 50°C. The pre-treatment of milk at 70°C resulted in highest clotting activity. Enzyme assays in presence of protease inhibitors indicated the presence of aspartic, cysteine, serine and metallo proteases. Aspartic proteases appear to be the main enzymes involved in milk-clotting activity. PP promoted extensive cleavage of κ-casein and low level of α(s)- and β-caseins hydrolysis. The milk-clotting activity indicates the application of M. oleifera flowers in dairy industry. Copyright © 2012 Elsevier Ltd. All rights reserved.

Alginate coating as carrier of oligofructose and inulin and to maintain the quality of fresh-cut apples.

PubMed

Rössle, Christian; Brunton, Nigel; Gormley, Ronan T; Wouters, Rudy; Butler, Francis

2011-01-01

The aim of this study was to apply an edible coating containing prebiotics such as oligofructose and inulin to fresh-cut apple wedges. An assessment of the quality, sensory, polyphenol, and volatile attributes of coated and uncoated fresh-cut apple wedges was also undertaken. Fructan analysis showed that all prebiotics remained stable over the 14-d storage period and an intake of 100 g of apple supplies 1 to 3 g of prebiotics. Browning index, firmness, acidity remained stable throughout the 14 d compared to the control while applying prebiotic coatings resulted in an increase in soluble solids. Sensory and visual assessment indicated acceptable quality of apple wedges coated with prebiotics. HPLC analysis showed that levels of polyphenolic compounds were more stable in coated apple wedges (without prebiotic inclusions) than in uncoated control apples. No difference was found between O(2) and CO(2) headspace concentration of coated and uncoated samples. Significant differences (P < 0.001) were found for headspace volatile production between the samples. Most coated samples showed lower volatile production in the headspace than uncoated samples.

In vitro storage characteristics of platelet concentrates suspended in 70% SSP+(TM) additive solution versus plasma over a 14-day storage period.

PubMed

Saunders, C; Rowe, G; Wilkins, K; Holme, S; Collins, P

2011-08-01

The non-paired two-arm study compared the in vitro storage characteristics of platelets suspended as concentrates in either 100% plasma or a mixture of additive solution (SSP+™, MacoPharma, Mouveaux, France) and autologous plasma in a 70:30 ratio over a 14-day storage period. The buffy coat-derived pooled platelet concentrates were sampled on days 1, 2, 3, 6, 8, 10 and 14 and tests performed to determine platelet morphology, function, metabolism, activation and apoptosis-like activity. Swirling remained strong (score=3) in SSP+™, whilst scores of 1 and 0 were noted for plasma units by end of storage. In contrast to units in plasma, pH levels remained above seven in SSP+™ units, increasing after day 10. Percent positive expression of CD62P was similar in both groups on day 1 (median of 54% and 56% for plasma (n=13) and SSP+™ (n=12), respectively), with SSP+™ units showing a more moderate increase in activation after day 10. A progressive decrease in mitochondrial membrane potential was evident in both groups from day 1, whilst annexin V binding was relatively stable from days 1 to 3, with median values remaining below 6%. Subsequent to this, the percentage of platelets binding annexin V increased to approximately 30% by day 14. Platelets suspended in a medium of 70:30 SSP+™ to plasma ratio performed at least as well as platelets in 100% autologous plasma for up to 10 days of storage. Further, results are suggestive of an apoptosis-like process being involved in the platelet storage lesion. © 2011 The Author(s). Vox Sanguinis © 2011 International Society of Blood Transfusion.

Stable Overexpression of the Constitutive Androstane Receptor Reduces the Requirement for Culture with Dimethyl Sulfoxide for High Drug Metabolism in HepaRG Cells.

PubMed

van der Mark, Vincent A; Rudi de Waart, D; Shevchenko, Valery; Elferink, Ronald P J Oude; Chamuleau, Robert A F M; Hoekstra, Ruurdtje

2017-01-01

Dimethylsulfoxide (DMSO) induces cellular differentiation and expression of drug metabolic enzymes in the human liver cell line HepaRG; however, DMSO also induces cell death and interferes with cellular activities. The aim of this study was to examine whether overexpression of the constitutive androstane receptor (CAR, NR1I3), the nuclear receptor controlling various drug metabolism genes, would sufficiently promote differentiation and drug metabolism in HepaRG cells, optionally without using DMSO. By stable lentiviral overexpression of CAR, HepaRG cultures were less affected by DMSO in total protein content and obtained increased resistance to acetaminophen- and amiodarone-induced cell death. Transcript levels of CAR target genes were significantly increased in HepaRG-CAR cultures without DMSO, resulting in increased activities of cytochrome P450 (P450) enzymes and bilirubin conjugation to levels equal or surpassing those of HepaRG cells cultured with DMSO. Unexpectedly, CAR overexpression also increased the activities of non-CAR target P450s, as well as albumin production. In combination with DMSO treatment, CAR overexpression further increased transcript levels and activities of CAR targets. Induction of CYP1A2 and CYP2B6 remained unchanged, whereas CYP3A4 was reduced. Moreover, the metabolism of low-clearance compounds warfarin and prednisolone was increased. In conclusion, CAR overexpression creates a more physiologically relevant environment for studies on hepatic (drug) metabolism and differentiation in HepaRG cells without the utilization of DMSO. DMSO still may be applied to accomplish higher drug metabolism, required for sensitive assays, such as low-clearance studies and identification of (rare) metabolites, whereas reduced total protein content after DMSO culture is diminished by CAR overexpression. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

A novel L-asparaginase from Aquabacterium sp. A7-Y with self-cleavage activation.

PubMed

Sun, Zhibin; Li, Ding; Liu, Pingping; Wang, Wenhui; Ji, Kai; Huang, Yan; Cui, Zhongli

2016-01-01

We have identified a novel L-asparaginase, abASNase3, from Aquabacterium sp. A7-Y. abASNase3 is composed of 306 amino acids and exhibits 34 % sequence homology to human asparaginase (hASNase3). Further analysis revealed that abASNase3 belongs to the N-terminal nucleophile (Ntn) family of hydrolases. Previous reports about the Ntn hydrolase family and the results of our study suggest that abASNase3 must form two subunits by self-cleavage between Gly189 and Thr190 to attain catalytic activity. The two subunits remained tightly associated to build a single functional unit. The optimum pH for abASNase3 was found to be 8.0 in Tris-HCl buffer and the enzyme was found to be stable over a broad pH range from pH 6.0 to 12.0. The optimum temperature for abASNase3 was found to be approximately 40 °C, and the enzyme was stable below 65 °C. abASNase3 showed high substrate specificity toward L-asparagine and had no or only slight activity toward D-asparagine, L-glutamine and D-glutamine. abASNase3 was significantly activated by Mg(2+) and was substantially inhibited by Ni(2+), Cu(2+), Mn(2+) and Co(2+). The Michaelis-Menten constant and turnover number of abASNase3 for L-asparagine were estimated to be 3.37 × 10(-2) M and 8.72 × 10(-3) s(-1), respectively. Our results indicate that abASNase3 is a novel L-asparaginase in the Ntn family of hydrolases.

Stability and change: Stress responses and the shaping of behavioral phenotypes over the life span.

PubMed

Hennessy, Michael B; Kaiser, Sylvia; Tiedtke, Tobias; Sachser, Norbert

2015-01-01

In mammals, maternal signals conveyed via influences on hypothalamic-pituitary-adrenal (HPA) activity may shape behavior of the young to be better adapted for prevailing environmental conditions. However, the mother's influence extends beyond classic stress response systems. In guinea pigs, several hours (h) of separation from the mother activates not only the HPA axis, but also the innate immune system, which effects immediate behavioral change, as well as modifies behavioral responsiveness in the future. Moreover, the presence of the mother potently suppresses the behavioral consequences of this innate immune activation. These findings raise the possibility that long-term adaptive behavioral change can be mediated by the mother's influence on immune-related activity of her pups. Furthermore, the impact of social partners on physiological stress responses and their behavioral outcomes are not limited to the infantile period. A particularly crucial period for social development in male guinea pigs is that surrounding the attainment of sexual maturation. At this time, social interactions with adults can dramatically affect circulating cortisol concentrations and social behavior in ways that appear to prepare the male to best cope in its likely future social environment. Despite such multiple social influences on the behavior of guinea pigs at different ages, inter-individual differences in the magnitude of the cortisol response remain surprisingly stable over most of the life span. Together, it appears that throughout the life span, physiological stress responses may be regulated by social stimuli. These influences are hypothesized to adjust behavior for predicted environmental conditions. In addition, stable individual differences might provide a means of facilitating adaptation to less predictable conditions.

Hepatic macrophage activation and the LPS pathway in patients with alcoholic hepatitis: a prospective cohort study.

PubMed

Sandahl, Thomas Damgaard; Grønbaek, Henning; Møller, Holger Jon; Støy, Sidsel; Thomsen, Karen Luise; Dige, Anders Kirch; Agnholt, Jørgen; Hamilton-Dutoit, Stephen; Thiel, Steffen; Vilstrup, Hendrik

2014-11-01

Inflammatory activation of resident hepatic macrophages (Kupffer cells) by portal-derived lipopolysaccharide (LPS) has a primary role in animal models of alcoholic liver disease, but it has not been systematically or longitudinally studied in human alcoholic hepatitis (AH). We followed 50 patients with AH for 30 days. 26 patients with stable alcoholic cirrhosis and 20 healthy individuals were controls. We measured the plasma (P) concentrations of soluble CD163 (sCD163; a specific marker of inflammatory macrophage activation) and the expression of CD163 in liver tissue by immunohistochemistry and stereology of liver biopsies. We also measured the key components of the LPS pathway, P-LPS, sCD14, and LPS-binding protein (LBP), by enzyme-linked immunosorbent assay (ELISA). The 84-day mortality was registered. At study entry, the sCD163 concentration was 10-fold higher than in the healthy controls and 30% higher than in the stable cirrhotics (P<0.002), and it correlated with the Glasgow Alcoholic Hepatitis, Model for End-stage Liver Disease, and Child-Pugh scores (r>0.35, P<0.02, all). The liver biopsies confirmed markedly increased CD163 staining (P<0.01). P-LPS, P-CD14, and P-LBP were increased to the same degree as sCD163. During the follow-up, the sCD163 and LPS pathway components all decreased by ∼25% (P<0.05) but remained higher than in both control groups. sCD163 was an independent predictor of the 84-day mortality. The hepatic inflammation of human AH involves marked activation of hepatic macrophages, likely via the LPS pathway. Hepatic macrophages may thus present a target for biological therapy of AH.

Some probiotic and antibacterial properties of Lactobacillus acidophilus cultured from dahi a native milk product.

PubMed

Mahmood, Talat; Masud, Tariq; Sohail, Asma

2014-08-01

In this study, different strains of Lactobacillus acidophilus from dahi were analyzed for certain probiotic and antibacterial properties. Initially, these strains were confirmed by the amplification of 16S rRNA regions and then screened for antibacterial activities against food borne pathogens. The phenotypic relationship between apparent antibacterial activity and cell wall proteins were established by cluster analysis. It was observed that those strains, which have prominent bands having size 22-25 kDa possess antibacterial activity. On the basis of wide spectrum of killing pattern, a strain LA06FT was further characterized that showed no change in its behavior when subjected to the antibiotic protected environment and grow well in acid-bile conditions. The bacteriocin produced by this strain has specific antibacterial activity of 5369.13 AU mg(-1). It remained stable at 60-90 °C and pH range of 4.5-6.5 while proteolytic enzymes inactivate the bacteriocin that confirm its proteinic nature having molecular weight of ≤8.5 kDa.

Response surface methodology as an approach to determine the optimal activities of xylose reductase and xylitol dehydrogenase enzymes from Candida Mogii.

PubMed

Mayerhoff, Zea D V L; Roberto, Inês C; Franco, Telma T

2006-05-01

A central composite experimental design leading to a set of 16 experiments with different combinations of pH and temperature was performed to attain the optimal activities of xylose reductase (XR) and xylitol dehydrogenase (XDH) enzymes from Candida mogii cell extract. Under optimized conditions (pH 6.5 and 38 degrees C), the XR and XDH activities were found to be 0.48 U/ml and 0.22 U/ml, respectively, resulting in an XR to XDH ratio of 2.2. Stability, cofactor specificity and kinetic parameters of the enzyme XR were also evaluated. XR activity remained stable for 3 h under 4 and 38 degrees C and for 4 months of storage at -18 degrees C. Studies on cofactor specificity showed that only NADPH-dependent XR was obtained under the cultivation conditions employed. The XR present in C. mogii extracts showed a superior Km value for xylose when compared with other yeast strains. Besides, this parameter was not modified after enzyme extraction by aqueous two-phase system.

Catalytic properties of thermophilic lactate dehydrogenase and halophilic malate dehydrogenase at high temperature and low water activity.

PubMed

Hecht, K; Wrba, A; Jaenicke, R

1989-07-15

Thermophilic lactate dehydrogenases from Thermotoga maritima and Bacillus stearothermophilus are stable up to temperature limits close to the optimum growth temperature of their parent organisms. Their catalytic properties are anomalous in that Km shows a drastic increase with increasing temperature. At low temperatures, the effect levels off. Extreme halophilic malate dehydrogenase from Halobacterium marismortui exhibits a similar anomaly. Increasing salt concentration (NaCl) leads to an optimum curve for Km, oxaloacctate while Km, NADH remains constant. Previous claims that the activity of halophilic malate dehydrogenase shows a maximum at 1.25 M NaCl are caused by limiting substrate concentration; at substrate saturation, specific activity of halophilic malate dehydrogenase reaches a constant value at ionic strengths I greater than or equal to 1 M. Non-halophilic (mitochondrial) malate dehydrogenase shows Km characteristics similar to those observed for the halophilic enzyme. The drastic decrease in specific activity of the mitochondrial enzyme at elevated salt concentrations is caused by the salt-induced increase in rigidity of the enzyme, rather than gross structural changes.

A hybrid brain-computer interface based on the fusion of electroencephalographic and electromyographic activities

NASA Astrophysics Data System (ADS)

Leeb, Robert; Sagha, Hesam; Chavarriaga, Ricardo; Millán, José del R.

2011-04-01

Hybrid brain-computer interfaces (BCIs) are representing a recent approach to develop practical BCIs. In such a system disabled users are able to use all their remaining functionalities as control possibilities in parallel with the BCI. Sometimes these people have residual activity of their muscles. Therefore, in the presented hybrid BCI framework we want to explore the parallel usage of electroencephalographic (EEG) and electromyographic (EMG) activity, whereby the control abilities of both channels are fused. Results showed that the participants could achieve a good control of their hybrid BCI independently of their level of muscular fatigue. Thereby the multimodal fusion approach of muscular and brain activity yielded better and more stable performance compared to the single conditions. Even in the case of an increasing muscular fatigue a good control (moderate and graceful degradation of the performance compared to the non-fatigued case) and a smooth handover could be achieved. Therefore, such systems allow the users a very reliable hybrid BCI control although they are getting more and more exhausted or fatigued during the day.

Purification and characterization of a novel thermostable mycelial lectin from Aspergillus terricola.

PubMed

Singh, Ram Sarup; Bhari, Ranjeeta; Kaur, Hemant Preet; Vig, Monika

2010-11-01

Lectin has been isolated from mycelia of Aspergillus terricola by single step purification on porcine stomach mucin-Sepharose 4B affinity column. Lectin could be effectively purified with 75% recovery and 4.47-fold increase in specific activity. Lectin migrated as a single band on SDS-PAGE with an apparent molecular mass of 32.5 kDa. Sugar inhibition assay revealed that the lectin did not strongly interact with most carbohydrates and their derivatives tested while strong binding affinity to D-glucose, D-sucrose, N-acetyl-D-galactosamine, asialofetuin, porcine stomach mucin, and bovine submaxillary mucin was indicated. Neuraminidase and protease treatment to erythrocytes enhanced lectin titre. Lectin activity was stable within the pH range of 7.0-10.5. A. terricola lectin displayed remarkable thermostability and remained unaffected upon incubation at 70 degrees C for 2.5 h. Lectin did not require metal ions for its activity. Incubation with denaturants (urea, thiourea, and guanidine-HCl) substantially reduced lectin activity. Carbohydrate analysis revealed that it is a glycoprotein with 9.76% total sugars.

Glucose modulates food-related salience coding of midbrain neurons in humans.

PubMed

Ulrich, Martin; Endres, Felix; Kölle, Markus; Adolph, Oliver; Widenhorn-Müller, Katharina; Grön, Georg

2016-12-01

Although early rat studies demonstrated that administration of glucose diminishes dopaminergic midbrain activity, evidence in humans has been lacking so far. In the present functional magnetic resonance imaging study, glucose was intravenously infused in healthy human male participants while seeing images depicting low-caloric food (LC), high-caloric food (HC), and non-food (NF) during a food/NF discrimination task. Analysis of brain activation focused on the ventral tegmental area (VTA) as the origin of the mesolimbic system involved in salience coding. Under unmodulated fasting baseline conditions, VTA activation was greater during HC compared with LC food cues. Subsequent to infusion of glucose, this difference in VTA activation as a function of caloric load leveled off and even reversed. In a control group not receiving glucose, VTA activation during HC relative to LC cues remained stable throughout the course of the experiment. Similar treatment-specific patterns of brain activation were observed for the hypothalamus. The present findings show for the first time in humans that glucose infusion modulates salience coding mediated by the VTA. Hum Brain Mapp 37:4376-4384, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Polymerase III transcription factor B activity is reduced in extracts of growth-restricted cells.

PubMed Central

Tower, J; Sollner-Webb, B

1988-01-01

Extracts of cells that are down-regulated for transcription by RNA polymerase I and RNA polymerase III exhibit a reduced in vitro transcriptional capacity. We have recently demonstrated that the down-regulation of polymerase I transcription in extracts of cycloheximide-treated and stationary-phase cells results from a lack of an activated subform of RNA polymerase I which is essential for rDNA transcription. To examine whether polymerase III transcriptional down-regulation occurs by a similar mechanism, the polymerase III transcription factors were isolated and added singly and in pairs to control cell extracts and to extracts of cells that had reduced polymerase III transcriptional activity due to cycloheximide treatment or growth into stationary phase. These down-regulations result from a specific reduction in TFIIIB; TFIIIC and polymerase III activities remain relatively constant. Thus, although transcription by both polymerase III and polymerase I is substantially decreased in extracts of growth-arrested cells, this regulation is brought about by reduction of different kinds of activities: a component of the polymerase III stable transcription complex in the former case and the activated subform of RNA polymerase I in the latter. Images PMID:3352599

Development of a homogeneous, fluorescence resonance energy transfer-based in vitro recruitment assay for peroxisome proliferator-activated receptor delta via selection of active LXXLL coactivator peptides.

PubMed

Drake, Katherine A; Zhang, Ji-Hu; Harrison, Richard K; McGeehan, Gerald M

2002-05-01

The peroxisome proliferator-activated receptors (PPARs) are nuclear receptors activated by fatty acids and their metabolites. The PPARdelta subtype is believed to be involved in lipoprotein regulation and may have a role in reverse cholesterol transport. While the range of biological roles of PPARdelta still remains unclear, it is of therapeutic interest in cardiovascular diseases. Here we report a homogeneous in vitro assay for studying ligand activation of PPARdelta. We surveyed a panel of peptides containing the LXXLL motifs derived from coactivator protein sequences. Peptides with the best response were used to develop a sensitive and homogeneous recruitment assay for PPARdelta. The optimized assay has a signal-to-background ratio of about 8:1 and an assay quality parameter Z'-factor value of 0.8. The assay signal generated is stable for hours to even overnight. This simple recruitment assay can provide agonist and/or antagonist information that cannot be assessed by receptor-binding assay, and can be used for characterization and screening of ligands that modulate the activation of PPARdelta. (c)2002 Elsevier Science (USA).

The temperate Burkholderia phage AP3 of the Peduovirinae shows efficient antimicrobial activity against B. cenocepacia of the IIIA lineage.

PubMed

Roszniowski, Bartosz; Latka, Agnieszka; Maciejewska, Barbara; Vandenheuvel, Dieter; Olszak, Tomasz; Briers, Yves; Holt, Giles S; Valvano, Miguel A; Lavigne, Rob; Smith, Darren L; Drulis-Kawa, Zuzanna

2017-02-01

Burkholderia phage AP3 (vB_BceM_AP3) is a temperate virus of the Myoviridae and the Peduovirinae subfamily (P2likevirus genus). This phage specifically infects multidrug-resistant clinical Burkholderia cenocepacia lineage IIIA strains commonly isolated from cystic fibrosis patients. AP3 exhibits high pairwise nucleotide identity (61.7 %) to Burkholderia phage KS5, specific to the same B. cenocepacia host, and has 46.7-49.5 % identity to phages infecting other species of Burkholderia. The lysis cassette of these related phages has a similar organization (putative antiholin, putative holin, endolysin, and spanins) and shows 29-98 % homology between specific lysis genes, in contrast to Enterobacteria phage P2, the hallmark phage of this genus. The AP3 and KS5 lysis genes have conserved locations and high amino acid sequence similarity. The AP3 bacteriophage particles remain infective up to 5 h at pH 4-10 and are stable at 60 °C for 30 min, but are sensitive to chloroform, with no remaining infective particles after 24 h of treatment. AP3 lysogeny can occur by stable genomic integration and by pseudo-lysogeny. The lysogenic bacterial mutants did not exhibit any significant changes in virulence compared to wild-type host strain when tested in the Galleria mellonella moth wax model. Moreover, AP3 treatment of larvae infected with B. cenocepacia revealed a significant increase (P < 0.0001) in larvae survival in comparison to AP3-untreated infected larvae. AP3 showed robust lytic activity, as evidenced by its broad host range, the absence of increased virulence in lysogenic isolates, the lack of bacterial gene disruption conditioned by bacterial tRNA downstream integration site, and the absence of detected toxin sequences. These data suggest that the AP3 phage is a promising potent agent against bacteria belonging to the most common B. cenocepacia IIIA lineage strains.

Trends in disability of instrumental activities of daily living among older Chinese adults, 1997-2006: population based study.

PubMed

Liang, Yajun; Welmer, Anna-Karin; Möller, Jette; Qiu, Chengxuan

2017-08-28

Data on trends for disability in instrumental activity of daily living (IADL) are sparse in older Chinese adults. To assess trends in prevalence and incidence of IADL disability among older Chinese adults and to explore contributing factors. Population based study. 15 provinces and municipalities in China. Participants (age ≥60) were from four waves of the China Health and Nutrition Survey, conducted in 1997 (n=1533), 2000 (n=1581), 2004 (n=2028) and 2006 (n=2256), and from two cohorts constructed within the national survey: cohort 1997-2004 (n=712) and cohort 2000-2006 (n=823). IADL disability was defined as inability to perform one or more of the following: shopping, cooking, using transportation, financing and telephoning. Data were analysed with logistic regression and generalised estimating equation models. The prevalence of IADL disability significantly decreased from 1997 to 2006 in the total sample and in all of the subgroups by age, sex, living region and IADL items (all p trend <0.05). The incidence of IADL disability remained stable from cohort 1997-2004 to cohort 2000-2006 in the total sample and in all of the subgroups (all p>0.10). The recovery rate from IADL disability significantly increased over time in those aged 60-69 years (p=0.03). Living in a rural area or access to local clinics for healthcare was less disabling over time (p trend <0.02). The prevalence of IADL disability decreased among older Chinese adults during 1997-2006, whereas the incidence remained stable. The declining prevalence of IADL disability might be partly due to the decreased duration of IADL disability, and to improvements in living conditions and healthcare facilities over time. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

"Long-term stability of stimulating spiral nerve cuff electrodes on human peripheral nerves".

PubMed

Christie, Breanne P; Freeberg, Max; Memberg, William D; Pinault, Gilles J C; Hoyen, Harry A; Tyler, Dustin J; Triolo, Ronald J

2017-07-11

Electrical stimulation of the peripheral nerves has been shown to be effective in restoring sensory and motor functions in the lower and upper extremities. This neural stimulation can be applied via non-penetrating spiral nerve cuff electrodes, though minimal information has been published regarding their long-term performance for multiple years after implantation. Since 2005, 14 human volunteers with cervical or thoracic spinal cord injuries, or upper limb amputation, were chronically implanted with a total of 50 spiral nerve cuff electrodes on 10 different nerves (mean time post-implant 6.7 ± 3.1 years). The primary outcome measures utilized in this study were muscle recruitment curves, charge thresholds, and percent overlap of recruited motor unit populations. In the eight recipients still actively involved in research studies, 44/45 of the spiral contacts were still functional. In four participants regularly studied over the course of 1 month to 10.4 years, the charge thresholds of the majority of individual contacts remained stable over time. The four participants with spiral cuffs on their femoral nerves were all able to generate sufficient moment to keep the knees locked during standing after 2-4.5 years. The dorsiflexion moment produced by all four fibular nerve cuffs in the active participants exceeded the value required to prevent foot drop, but no tibial nerve cuffs were able to meet the plantarflexion moment that occurs during push-off at a normal walking speed. The selectivity of two multi-contact spiral cuffs was examined and both were still highly selective for different motor unit populations for up to 6.3 years after implantation. The spiral nerve cuffs examined remain functional in motor and sensory neuroprostheses for 2-11 years after implantation. They exhibit stable charge thresholds, clinically relevant recruitment properties, and functional muscle selectivity. Non-penetrating spiral nerve cuff electrodes appear to be a suitable option for long-term clinical use on human peripheral nerves in implanted neuroprostheses.

Metapopulation viability of an endangered shorebird depends on dispersal and human-created habitats: Piping plovers (Charadrius melodus) and prairie rivers

USGS Publications Warehouse

Catlin, Daniel H.; Zeigler, Sara; Bomberger Brown, M.; Dinan, Lauren R.; Fraser, James D.; Hunt, Kelsi L.; Jorgensen, Joel G.

2016-01-01

We found that functional connectivity, as measured by the rate of dispersal among subpopulations, increased as a result of the high flow event in our study metapopulation. Plovers also increased reproductive output following this event. Although the study metapopulation had a low overall probability of extinction, metapopulation persistence depended on anthropogenically created habitats that provided a small but stable source of nesting habitat and dispersers through time. However, all subpopulations remained small, even if persistent, making them individually vulnerable to extinction through stochastic events. Given the highly dynamic nature of habitat availability in this system, maintaining several subpopulations within the metapopulation and stable sources of habitat will be critical, and this species will likely remain conservation-reliant.

Georgia, 2011 - forest inventory and analysis factsheet

Treesearch

Richard A. Harper

2012-01-01

Georgia contains the largest area of forest cover in the South with 24.8 million acres, accounting for 67 percent of the State’s land area (table 1). The forest area has remained relatively stable over the last 50 years. Commercial timberland area (land available for production of forest products) comprises >98 percent of the total forest land area. The remaining...

Future Pacific Rim flows and prices of softwood logs, differentiated by grade.

Treesearch

Donald F. Flora; Andrea L. Anderson; Wendy J. McGInnls

1990-01-01

By 2000, prices are expected to rise significantly for medium-grade logs and modestly for low-grade logs. World economic cycles may obscure, however, the upward price trends. Exports from the United States of medium grades are expected to remain stable, while volumes of lower grades are projected to remain level through 1995 and then decline because of competition....

Time trends in physical activity from 1982 to 2012 in Finland.

PubMed

Borodulin, K; Harald, K; Jousilahti, P; Laatikainen, T; Männistö, S; Vartiainen, E

2016-01-01

The aim of this study was to examine population trends from 1982 to 2012 in Finland for leisure time physical activity (LTPA), commuting physical activity (CPA), occupational physical activity (OPA), and total physical activity. Furthermore, time trends in physical activity by educational levels and body mass index (BMI) categories were explored. Data were collected in independent cross-sectional population surveys, implemented every 5 years from 1982 to 2012. The data comprised 21,903 men and 24,311 women. Participants underwent a health examination and filled in questionnaires. Information on LTPA, CPA, and OPA was used both separately and combined to create an index of total physical activity. Between 1982 and 2012, high LTPA has increased in men (from 21% to 33%) and women (from 12% to 27%). High CPA and high OPA have decreased in men (from 17% to 12% and from 48% to 36%, respectively) and women (from 30% to 20% and from 26% to 21%, respectively). Total physical activity has remained fairly stable. Differences by education and BMI have increased, particularly for LTPA. Marked changes in physical activity have taken place over time. Differences in LTPA and OPA have grown wider across educational groups and BMI categories. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Evaluation of the sterility, stability, and efficacy of bevacizumab stored in multiple-dose vials for 6 months.

PubMed

Chen, Yi-Hao; Wu, Pei-Chang; Shiea, Jentaie; Lo, Li-Hua; Wu, Yi-Chen; Kuo, Hsi-Kung

2009-02-01

The aim of this study was to determine the sterility, stability, and efficacy of a commercially available brand of bevacizumab for 6 months of being stored in multidose vials at 4 degrees C. Bevacizumab was aseptically and repeatedly drawn four to five times from new vials into syringes for clinical use within the first month; the remaining bevacizumab was left in the vials and refrigerated at 4 degrees C for 0, 1, 3, and 6 months for research. Each time before bevacizumab was withdrawn and every weekend when it was not sampled, the rubber top of each vial was disinfected by using 10% povidone-iodine solution and an isopropyl alcohol wipe. Each vial had been sampled for less than 12 times during the experimental periods. All vials were analyzed for microbial growth. The stability of bevacizumab was analyzed by MALDI-TOF MS (matrix-assisted laser desorption ionization/time-of-flight mass spectrometry). The efficacy of bevacizumab was analyzed by enzyme-linked immunosorbent assay (ELISA). At each time period, bevacizumab was mixed with vascular endothelial growth factor (VEGF)-165 and left undisturbed for 3 h. The efficacy of bevacizumab was then evaluated by measuring the concentration of residual-free VEGF-165. No microbial growth was obtained from any of the bevacizumab samples during each time period, indicating that the bevacizumab stored at 4 degrees C after the vials had been pierced remained sterile. MALDI-TOF MS analysis revealed that the 1-, 3-, and 6-month samples were stable, and there were no molecular-weight changes among any of the samples. The level of degradation of bevacizumab at 1, 3, and 6 months was compared with that of the control (0 months). The results of ELISA showed less than 10% degradation at all time periods. This study suggests that if aseptic precautions are followed while using bevacizumab, the contents of multiple-dose vials stored at 4 degrees C will remain sterile. The anti-VEGF activity of bevacizumab stored at 4 degrees C will remain stable for up to 6 months.

The effect of long-term nitrate treatment on SRB activity, corrosion rate and bacterial community composition in offshore water injection systems.

PubMed

Bødtker, Gunhild; Thorstenson, Tore; Lillebø, Bente-Lise P; Thorbjørnsen, Bente E; Ulvøen, Rikke Helen; Sunde, Egil; Torsvik, Terje

2008-12-01

Biogenic production of hydrogen sulphide (H(2)S) is a problem for the oil industry as it leads to corrosion and reservoir souring. Continuous injection of a low nitrate concentration (0.25-0.33 mM) replaced glutaraldehyde as corrosion and souring control at the Veslefrikk and Gullfaks oil field (North Sea) in 1999. The response to nitrate treatment was a rapid reduction in number and activity of sulphate-reducing bacteria (SRB) in the water injection system biofilm at both fields. The present long-term study shows that SRB activity has remained low at < or =0.3 and < or =0.9 microg H(2)S/cm(2)/day at Veslefrikk and Gullfaks respectively, during the 7-8 years with continuous nitrate injection. At Veslefrikk, 16S rRNA gene based community analysis by PCR-DGGE showed that bacteria affiliated to nitrate-reducing sulphide-oxidizing Sulfurimonas (NR-SOB) formed major populations at the injection well head throughout the treatment period. Downstream of deaerator the presence of Sulfurimonas like bacteria was less pronounced, and were no longer observed 40 months into the treatment period. The biofilm community during nitrate treatment was highly diverse and relative stable for long periods of time. At the Gullfaks field, a reduction in corrosion of up to 40% was observed after switch to nitrate treatment. The present study show that nitrate injection may provide a stable long-term inhibition of SRB in sea water injection systems, and that corrosion may be significantly reduced when compared to traditional biocide treatment.

Stability of FeNO and airway hyperresponsiveness to mannitol in untreated asthmatics.

PubMed

Udesen, Pernille Bækgaard; Westergaard, Christian Grabow; Porsbjerg, Celeste; Backer, Vibeke

2017-06-01

Airway hyperresponsiveness and airway inflammation are important hallmarks of asthma and are useful in asthma diagnosing, monitoring and treatment. The aim of the study was to assess whether two commonly used clinical tests, the mannitol challenge and Fraction of exhaled NO (FeNO), were stable clinical indicators over time in stable untreated asthmatics. 54 non-smoking, asthma patients not treated with steroids were enrolled in the study and assessed at baseline and a median of 6 months later. At baseline and follow-up, FeNO and airway hyperesponsiveness to mannitol were measured, and asthma control was assessed with the Asthma Control Questionnaire (ACQ). A total of 41 subjects completed both visits. Mean (SD) FEV1% at baseline was 94.1% (17.7) and at re-examination 94.6% (19.7) (ns). The ACQ score was unchanged from baseline (Mean (SD): 0.90 (± 0.73)) to follow-up 0.90 (± 0.74) (ns), as was the FEV 1 % (94.1% (±17.1%) vs 94.6% (19.7%)(ns) indicating that patients were clinically stable during follow-up. The response to mannitol was unchanged at follow-up (Geometric mean (CI) of Response Dose Ratio (RDR) to mannitol: 0.026(0.013-0.046) vs 0.026(0.012-0.050) (ns). There was a slight decrease in FeNO at follow-up (25.5 ppb (19.7-32.9) to 21.9 ppb (17.1-28.2) (p < 0.001). In steroid-free non-smoking asthmatics with constant symptom scores and lung function, airway responsiveness to mannitol remained at the same level over a period of months, while a minor change in exhaled FeNO was reported. These results suggest that mannitol is a stable, reliable marker of clinical disease activity.

Hydraulic retention time and pH affect the performance and microbial communities of passive bioreactors for treatment of acid mine drainage.

PubMed

Aoyagi, Tomo; Hamai, Takaya; Hori, Tomoyuki; Sato, Yuki; Kobayashi, Mikio; Sato, Yuya; Inaba, Tomohiro; Ogata, Atsushi; Habe, Hiroshi; Sakata, Takeshi

2017-12-01

For acceleration of removing toxic metals from acid mine drainage (AMD), the effects of hydraulic retention time (HRT) and pH on the reactor performance and microbial community structure in the depth direction of a laboratory-scale packed-bed bioreactor containing rice bran as waste organic material were investigated. The HRT was shortened stepwise from 25 to 12 h, 8 h, and 6 to 5 h under the neutral condition using AMD neutralized with limestone (pH 6.3), and from 25 to 20 h, 12 h, and 8 to 7 h under the acid condition using AMD (pH 3.0). Under the neutral condition, the bioreactor stably operated up to 6 h HRT, which was shorter than under the acid condition (up to 20 h HRT). During stable sulfate reduction, both the organic matter-remaining condition and the low oxidation-reduction potential condition in lower parts of the reactor were observed. Principal coordinate analysis of Illumina sequencing data of 16S rRNA genes revealed a dynamic transition of the microbial communities at the boundary between stable and unstable operation in response to reductions in HRT. During stable operation under both the neutral and acid conditions, several fermentative operational taxonomic units (OTUs) from the phyla Firmicutes and Bacteroidetes dominated in lower parts of the bioreactor, suggesting that co-existence of these OTUs might lead to metabolic activation of sulfate-reducing bacteria. In contrast, during unstable operation at shorter HRTs, an OTU from the candidate phylum OP11 were found under both conditions. This study demonstrated that these microorganisms can be used to monitor the treatment of AMD, which suggests stable or deteriorated performance of the system.

Electromyographic activity and 6RM strength in bench press on stable and unstable surfaces.

PubMed

Saeterbakken, Atle H; Fimland, Marius S

2013-04-01

The purpose of the study was to compare 6-repetition maximum (6RM) loads and muscle activity in bench press on 3 surfaces, namely, stable bench, balance cushion, and Swiss ball. Sixteen healthy, resistance-trained men (age 22.5 ± 2.0 years, stature 1.82 ± 6.6 m, and body mass 82.0 ± 7.8 kg) volunteered for 3 habituation/strength testing sessions and 1 experimental session. In randomized order on the 3 surfaces, 6RM strength and electromyographic activity of pectoralis major, deltoid anterior, biceps brachii, triceps brachii, rectus abdominis, oblique external and erector spinae were assessed. Relative to stable bench, the 6RM strength was approximately 93% for balance cushion (p ≤ 0.001) and approximately 92% for Swiss ball (p = 0.008); the pectoralis major electromyographic (EMG) activity was approximately 90% using the balance cushion (p = 0.080) and approximately 81% using Swiss ball (p = 0.006); the triceps EMG was approximately 79% using the balance cushion (p = 0.028) and approximately 69% using the Swiss ball (p = 0.002). Relative to balance cushion, the EMG activity in pectoralis, triceps, and erector spinae using Swiss ball was approximately 89% (p = 0.016), approximately 88% (p = 0.014) and approximately 80% (p = 0.020), respectively. In rectus abdominis, the EMG activity relative to Swiss ball was approximately 69% using stable bench (p = 0.042) and approximately 65% using the balance cushion (p = 0.046). Similar EMG activities between stable and unstable surfaces were observed for deltoid anterior, biceps brachii, and oblique external. In conclusion, stable bench press had greater 6RM strength and triceps and pectoralis EMG activity compared with the unstable surfaces. These findings have implications for athletic training and rehabilitation, because they demonstrate an inferior effect of unstable surfaces on muscle activation of prime movers and strength in bench press. If an unstable surface in bench press is desirable, a balance cushion should be chosen instead of a Swiss ball.

Implications of HLA-allele associations for the study of type IV drug hypersensitivity reactions.

PubMed

Sullivan, A; Watkinson, J; Waddington, J; Park, B K; Naisbitt, D J

2018-03-01

Type IV drug hypersensitivity remains an important clinical problem and an obstacle to the development of new drugs. Several forms of drug hypersensitivity are associated with expression of specific HLA alleles. Furthermore, drug-specific T-lymphocytes have been isolated from patients with reactions. Despite this, controversy remains as to how drugs interact with immune receptors to stimulate a T-cell response. Areas covered: This article reviews the pathways of T-cell activation by drugs and how the ever increasing number of associations between expression of HLA alleles and susceptibility to hypersensitivity is impacting on our research effort to understanding this form of iatrogenic disease. Expert opinion: For a drug to activate a T-cell, a complex is formed between HLA molecules, an HLA binding peptide, the drug and the T-cell receptor. T-cell responses can involve drugs and stable or reactive metabolites bound covalently or non-covalently to any component of this complex. Recent research has linked the HLA associations to the disease through the characterization of drug-specific T-cell responses restricted to specific alleles. However, there is now a need to identify the additional genetic or environment factors that determine susceptibility and use our increased knowledge to develop predictive immunogenicity tests that offer benefit to Pharma developing new drugs.

Conservative treatment of an acute traumatic extensor carpi ulnaris tendon subluxation in a collegiate basketball player: a case report.

PubMed

Patterson, Steve M; Picconatto, William J; Alexander, Julie A; Johnson, Rachel L

2011-01-01

To present the case of an acute traumatic extensor carpi ulnaris (ECU) subluxation in a National Collegiate Athletic Association Division II female basketball player. The ECU tendon is stabilized in the ulnar groove by a subsheath located inferior to the extensor retinaculum. The subsheath can be injured with forced supination, ulnar deviation, and wrist flexion, resulting in the ECU tendon subluxing in the palmar and ulnar directions during wrist circumduction. Several methods of intervention exist, but controversy remains on how to best treat this condition. Distal ulnar fracture, ulnar collateral ligament sprain, triangular fibrocartilage complex lesion, lunotriquetral instability, distal radioulnar joint injury, pisotriquetral joint injury, ECU tendinopathy or subluxation. The wrist was placed in a short-arm cast in slight extension and radial deviation for 4 weeks. At that time, the patient was still able to actively sublux the ECU tendon, so a long-arm cast was applied with the wrist in slight extension, radial deviation, and pronation for an additional 4 weeks. The ECU tendon was then found to be stable. She wore a rigid wrist brace for 3 more weeks while she pursued rehabilitation. At the final follow-up appointment, the ECU tendon remained stable, and the wrist was asymptomatic. Subluxations of the ECU are rare. If the patient does not improve with conservative measures, surgical intervention is warranted to repair the sixth dorsal compartment. A long-arm cast with the elbow flexed to 90° and the wrist in approximately 30° of extension, radial deviation, and pronation was appropriate treatment for this type of injury.

Trends in the surgical management of stress urinary incontinence among female Medicare beneficiaries, 2002-2007.

PubMed

Rogo-Gupta, Lisa; Litwin, Mark S; Saigal, Christopher S; Anger, Jennifer T

2013-07-01

To describe trends in the surgical management of female stress urinary incontinence (SUI) in the United States from 2002 to 2007. As part of the Urologic Diseases of America Project, we analyzed data from a 5% national random sample of female Medicare beneficiaries aged 65 and older. Data were obtained from the Centers for Medicare and Medicaid Services carrier and outpatient files from 2002 to 2007. Women who were diagnosed with urinary incontinence identified by the International Classification of Diseases, Ninth Edition (ICD-9) diagnosis codes and who underwent surgical management identified by Current Procedural Terminology, Fourth Edition (CPT-4) procedure codes were included in the analysis. Trends were analyzed over the 6-year period. Unweighted procedure counts were multiplied by 20 to estimate the rate among all female Medicare beneficiaries. The total number of surgical procedures remained stable during the study period, from 49,340 in 2002 to 49,900 in 2007. Slings were the most common procedure across all years, which increased from 25,840 procedures in 2002 to 33,880 procedures in 2007. Injectable bulking agents were the second most common procedure, which accounted for 14,100 procedures in 2002 but decreased to 11,320 in 2007. Procedures performed in ambulatory surgery centers and physician offices increased, although those performed in inpatient settings declined. Hospital outpatient procedures remained stable. The surgical management of women with SUI shifted toward a dominance of procedures performed in ambulatory surgery centers from 2002 to 2007, although the overall number of procedures remained stable. Slings remained the dominant surgical procedure, followed by injectable bulking agents, both of which are easily performed in outpatient settings. Copyright © 2013 Elsevier Inc. All rights reserved.

Stable Water Use Efficiency under Climate Change of Three Sympatric Conifer Species at the Alpine Treeline

PubMed Central

Wieser, Gerhard; Oberhuber, Walter; Gruber, Andreas; Leo, Marco; Matyssek, Rainer; Grams, Thorsten Erhard Edgar

2016-01-01

The ability of treeline associated conifers in the Central Alps to cope with recent climate warming and increasing CO2 concentration is still poorly understood. We determined tree ring stable carbon and oxygen isotope ratios of Pinus cembra, Picea abies, and Larix decidua trees from 1975 to 2010. Stable isotope ratios were compared with leaf level gas exchange measurements carried out in situ between 1979 and 2007. Results indicate that tree ring derived intrinsic water-use efficiency (iWUE) of P. cembra, P. abies and L. decidua remained constant during the last 36 years despite climate warming and rising atmospheric CO2. Temporal patterns in Δ13C and Δ18O mirrored leaf level gas exchange assessments, suggesting parallel increases of CO2-fixation and stomatal conductance of treeline conifer species. As at the study site soil water availability was not a limiting factor iWUE remained largely stable throughout the study period. The stability in iWUE was accompanied by an increase in basal area increment (BAI) suggesting that treeline trees benefit from both recent climate warming and CO2 fertilization. Finally, our results suggest that iWUE may not change species composition at treeline in the Austrian Alps due to similar ecophysiological responses to climatic changes of the three sympatric study species. PMID:27375653

Litter type control on soil C and N stabilization dynamics in a temperate forest.

PubMed

Hatton, Pierre-Joseph; Castanha, Cristina; Torn, Margaret S; Bird, Jeffrey A

2015-03-01

While plant litters are the main source of soil organic matter (SOM) in forests, the controllers and pathways to stable SOM formation remain unclear. Here, we address how litter type ((13) C/(15) N-labeled needles vs. fine roots) and placement-depth (O vs. A horizon) affect in situ C and N dynamics in a temperate forest soil after 5 years. Litter type rather than placement-depth controlled soil C and N retention after 5 years in situ, with belowground fine root inputs greatly enhancing soil C (x1.4) and N (x1.2) retention compared with aboveground needles. While the proportions of added needle and fine root-derived C and N recovered into stable SOM fractions were similar, they followed different transformation pathways into stable SOM fractions: fine root transfer was slower than for needles, but proportionally more of the remaining needle-derived C and N was transferred into stable SOM fractions. The stoichiometry of litter-derived C vs. N within individual SOM fractions revealed the presence at least two pools of different turnover times (per SOM fraction) and emphasized the role of N-rich compounds for long-term persistence. Finally, a regression approach suggested that models may underestimate soil C retention from litter with fast decomposition rates. © 2014 John Wiley & Sons Ltd.

Dynamics of carbon pools in post-agrogenic sandy soils of southern taiga of Russia.

PubMed

Kalinina, Olga; Goryachkin, Sergey V; Karavaeva, Nina A; Lyuri, Dmitriy I; Giani, Luise

2010-04-26

Until recently, a lot of arable lands were abandoned in many countries of the world and, especially, in Russia, where about half a million square kilometers of arable lands were abandoned in 1961-2007. The soils at these fallows undergo a process of natural restoration (or self-restoration) that changes the balance of soil organic matter (SOM) supply and mineralization. A soil chronosequence study, covering the ecosystems of 3, 20, 55, 100, and 170 years of self-restoration in southern taiga zone, shows that soil organic content of mineral horizons remains relatively stable during the self-restoration. This does not imply, however, that SOM pools remain steady. The C/N ratio of active SOM reached steady state after 55 years, and increased doubly (from 12.5 - 15.6 to 32.2-33.8). As to the C/N ratio of passive SOM, it has been continuously increasing (from 11.8-12.7 to 19.0-22.8) over the 170 years, and did not reach a steady condition. The results of the study imply that soil recovery at the abandoned arable sandy lands of taiga is incredibly slow process. Not only soil morphological features of a former ploughing remained detectable but also the balance of soil organic matter input and mineralization remained unsteady after 170 years of self-restoration.

Dynamics of carbon pools in post-agrogenic sandy soils of southern taiga of Russia

PubMed Central

2010-01-01

Background Until recently, a lot of arable lands were abandoned in many countries of the world and, especially, in Russia, where about half a million square kilometers of arable lands were abandoned in 1961-2007. The soils at these fallows undergo a process of natural restoration (or self-restoration) that changes the balance of soil organic matter (SOM) supply and mineralization. Results A soil chronosequence study, covering the ecosystems of 3, 20, 55, 100, and 170 years of self-restoration in southern taiga zone, shows that soil organic content of mineral horizons remains relatively stable during the self-restoration. This does not imply, however, that SOM pools remain steady. The C/N ratio of active SOM reached steady state after 55 years, and increased doubly (from 12.5 - 15.6 to 32.2-33.8). As to the C/N ratio of passive SOM, it has been continuously increasing (from 11.8-12.7 to 19.0-22.8) over the 170 years, and did not reach a steady condition. Conclusion The results of the study imply that soil recovery at the abandoned arable sandy lands of taiga is incredibly slow process. Not only soil morphological features of a former ploughing remained detectable but also the balance of soil organic matter input and mineralization remained unsteady after 170 years of self-restoration. PMID:20420668

Organ donation and transplantation statistics in Belgium for 2012 and 2013.

PubMed

Desschans, B; Evrard, P

2014-11-01

The 2012 and 2013 solid organ transplantation statistics were presented during the annual meeting of the Belgian Transplant Society. All data presented were collected from Eurotransplant International Foundation and/or from all individual Belgian transplant centers. It was demonstrated that the highest number of deceased donors detected (1310) from which 47.8% were an effective organ donor that corresponded to 29 per million inhabitants (pmi) in 2012 and 27.4 pmi in 2013. Out of 626 effective deceased organ donors, 491 (79%) were donors after brain death (DBD) and 135 (21%) donors after circulatory death (DCD), respectively. The majority (125/135; 93%) of DCD donors were DCD Maastricht category III donors and there were 7 (5%) donations following euthanasia. Family refusal tended to be lower for DCD (10.4%) compared to DBD donors (13.4%). Despite the increasing DCD donation rate, DBD donation remains stable in Belgium. The donor age is still increasing, reaching a median age of 53 years (range 0-90). Spontaneous intracranial bleeding (39.3%) and cranio-cerebral trauma (25%) remained the most frequent reasons of death. The number of living related kidney transplantations (57 in 2012 and 63 in 2013) followed the international trend albeit in Belgium it is still very limited. Nevertheless this activity could explain that the number of patients waiting for kidney transplantation (770) reached an absolute minimum in 2013. Except the reduced waiting list for lung transplantation (from 119 patients in 2011 to 85 in 2013), the waiting list remained stable for the other organs but almost 200 patients still died while on the waiting list. Belgium demonstrated the highest number of effective organ donors that corresponded to 29 per million inhabitants (pmi) in 2012 and 27.4 pmi in 2013. Thus far, and in contrast with other countries, there is no erosion of DBD in the DCD donor organ pool, but it is the important responsibility of all transplant centers and donor hospitals to avoid a substitution from DBD by DCD donors.

Alternative catalysts for low-temperature CO-oxidation

NASA Technical Reports Server (NTRS)

Gardner, Steven D.; Hoflund, Gar B.; Schryer, David R.; Schryer, Jacqueline; Upchurch, Billy T.; Brown, David R.

1990-01-01

MnO sub x, Ag/MnO sub x, Cu/MnO sub x, Pt/MnO sub x, Ru/MnO sub x, Au/CeO sub x, and Au/Fe2O3 were synthesized and tested for CO oxidation activity in low concentrations of stoichiometric CO and O2 at 30 to 75 C. Catalytic activity was measured for periods as long as 18000 minutes. At 75 deg Au/MnO sub x is most active sustaining nearly 100 percent CO conversion for 10000 minutes. It also retains high activity at 50 and 30 C with negligible decay in activity. A direct comparison between an unpretreated 10 percent Au/MnO sub x catalyst and an optimized 19.5 percent Pt/SnO sub 2 (pretreated) catalyst shows that the Au/MnO sub x catalyst exhibits much higher catalytic activity and far superior decay characteristics. Other catalysts including Au/CeO sub x and Au/Fe2O3 also perform well. The Cu/MnO sub x exhibits a high initial activity which decays rapidly. After the decay period the activity remains very stable making Cu/MnO sub x a potential candidate for long-term applications such as CO2 lasers in space.

Changes in active travel of school children from 2004 to 2010 in New South Wales, Australia.

PubMed

Meron, Dafna; Rissel, Chris; Reinten-Reynolds, Tracie; Hardy, Louise L

2011-12-01

To describe changes in mode of commuting to school among Australia students between 2004 and 2010 and in relation to body mass index (BMI) and cardio respiratory fitness. Representative cross-sectional survey of school children in grades 6, 8 and 10 in 2004 (n=2750) and 2010 (n=4273). Information on how many days students use active and passive travel modes to and from school and measured BMI and cardio-respiratory fitness test were collected as part of the New South Wales (NSW) Schools Physical Activity and Nutrition Surveys (SPANS). Active travel to school remained stable between 2004 and 2010, although there was a small increase in minutes spent on active travel. There was no association between active travel and body mass index. In 2010 there was a significant association between frequent car use and low cardio-respiratory fitness (adjusted OR=1.7, CI 1.3-2.1). It is a positive finding that the generational decline in active travel may have levelled out. Student inactivity associated with regular car use is plausibly related to lower cardio-respiratory fitness, but active commuting may not be of sufficient energy expenditure to impact upon BMI. Copyright © 2011 Elsevier Inc. All rights reserved.

Topological defects in confined populations of spindle-shaped cells

NASA Astrophysics Data System (ADS)

Duclos, Guillaume; Erlenkämper, Christoph; Joanny, Jean-François; Silberzan, Pascal

2017-01-01

Most spindle-shaped cells (including smooth muscles and sarcomas) organize in vivo into well-aligned `nematic’ domains, creating intrinsic topological defects that may be used to probe the behaviour of these active nematic systems. Active non-cellular nematics have been shown to be dominated by activity, yielding complex chaotic flows. However, the regime in which live spindle-shaped cells operate, and the importance of cell-substrate friction in particular, remains largely unexplored. Using in vitro experiments, we show that these active cellular nematics operate in a regime in which activity is effectively damped by friction, and that the interaction between defects is controlled by the system’s elastic nematic energy. Due to the activity of the cells, these defects behave as self-propelled particles and pairwise annihilate until all displacements freeze as cell crowding increases. When confined in mesoscopic circular domains, the system evolves towards two identical +1/2 disclinations facing each other. The most likely reduced positions of these defects are independent of the size of the disk, the cells’ activity or even the cell type, but are well described by equilibrium liquid crystal theory. These cell-based systems thus operate in a regime more stable than other active nematics, which may be necessary for their biological function.

Metastable state en route to traveling-wave synchronization state

NASA Astrophysics Data System (ADS)

Park, Jinha; Kahng, B.

2018-02-01

The Kuramoto model with mixed signs of couplings is known to produce a traveling-wave synchronized state. Here, we consider an abrupt synchronization transition from the incoherent state to the traveling-wave state through a long-lasting metastable state with large fluctuations. Our explanation of the metastability is that the dynamic flow remains within a limited region of phase space and circulates through a few active states bounded by saddle and stable fixed points. This complex flow generates a long-lasting critical behavior, a signature of a hybrid phase transition. We show that the long-lasting period can be controlled by varying the density of inhibitory/excitatory interactions. We discuss a potential application of this transition behavior to the recovery process of human consciousness.

ON TEMPORAL VARIATIONS OF THE MULTI-TeV COSMIC RAY ANISOTROPY USING THE TIBET III AIR SHOWER ARRAY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Amenomori, M.; Bi, X. J.; Ding, L. K.

2010-03-01

We analyze the large-scale two-dimensional sidereal anisotropy of multi-TeV cosmic rays (CRs) by the Tibet Air Shower Array, with the data taken from 1999 November to 2008 December. To explore temporal variations of the anisotropy, the data set is divided into nine intervals, each with a time span of about one year. The sidereal anisotropy of magnitude, about 0.1%, appears fairly stable from year to year over the entire observation period of nine years. This indicates that the anisotropy of TeV Galactic CRs remains insensitive to solar activities since the observation period covers more than half of the 23rd solarmore » cycle.« less

Spin-labeling of Dexamethasone: Radical Stability vs. Temporal Resolution of EPR-Spectroscopy on Biological Samples

NASA Astrophysics Data System (ADS)

Walker, Karolina A.; Unbehauen, Michael L.; Lohan, Silke B.; Saeidpour, Siavash; Meinke, Martina C.; Zimmer, Reinhold; Haag, Rainer

2018-05-01

Spin-labeling active compounds is a convenient way to prepare them for EPR spectroscopy with minimal alteration of the target molecule. In this study we present the labeling reaction of dexamethasone (Dx) with either TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy) or PCA (3-(carboxy)-2,2,5,5-tetramethyl-1-pyrrolidinyloxy) with high yields. According to NMR data, both labels are attached at the primary hydroxy group of the steroid. In subsequent spin-stability measurements both compounds were applied onto HaCaT cells. When the signal of Dx-TEMPO decreased below the detection limit within 3 h, the signal of Dx-PCA remained stable for the same period of time.

Features of the damage produced by proflavine on transforming deoxyribonucleic acid.

PubMed

Cabrera-Juárez, E; Sánchez-Rincón, D A

1979-03-01

Proflavine formed a complex with transforming deoxyribonucleic acid (DNA) from Haemophilus influenzae, with optimal formation at a ratio of proflavine to DNA of 0.06. The rate of dissociation of the complex by dialysis increased in the order: native, denatured, renatured DNA. The transforming activity of the DNA was reduced by its interaction with proflavine. This inactivation was dependent on the physical state of the DNA, the proflavine concentration, and the temperature. DNA that had been denatured and renatured was most sensitive; native DNA was much less sensitive. The inactivation remained after dialysis and was stable to prolonged storage. It is concluded that the inactivation of transforming DNA by proflavine takes place by a mechanism different from that of DNA-proflavine complex formation.

Effectiveness of varicella vaccine in children infected with HIV.

PubMed

Son, Moeun; Shapiro, Eugene D; LaRussa, Philip; Neu, Natalie; Michalik, David E; Meglin, Michelle; Jurgrau, Andrea; Bitar, Wally; Vasquez, Marietta; Flynn, Patricia; Gershon, Anne A

2010-06-15

Although varicella vaccine is given to clinically stable human immunodeficiency virus (HIV)-infected children, its effectiveness is unknown. We assessed its effectiveness by reviewing the medical records of closely monitored HIV-infected children, including those receiving highly active antiretroviral therapy (HAART) between 1989 and 2007. Varicella immunization and development of varicella or herpes zoster were noted. Effectiveness was calculated by subtracting from 1 the rate ratios for the incidence rates of varicella or herpes zoster in vaccinated versus unvaccinated children. The effectiveness of the vaccine was 82% (95% confidence interval [CI], 24%-99%; P = .01) against varicella and was 100% (95% CI, 67%-100%; P < .001) against herpes zoster. When the analysis was controlled for receipt of HAART, vaccination remained highly protective against herpes zoster.

Trajectories of Quality of Life after Hematopoietic Cell Transplantation: Secondary Analysis of BMT CTN 0902 Data

PubMed Central

Jim, Heather S.L.; Sutton, Steven K.; Small, Brent J.; Jacobsen, Paul B.; Wood, William A.; Knight, Jennifer M.; Majhail, Navneet S.; Syrjala, Karen L.; Lee, Stephanie J.

2016-01-01

Summary Quality of life is increasingly recognized as an important secondary endpoint of hematopoietic cell transplantation (HCT). The current study examined the extent to which attrition results in biased estimates of patient quality of life. The study also examined whether patients differ in terms of trajectories of quality of life in the first six months post-transplant. A secondary data analysis was conducted of 701 participants who enrolled in the Blood and Marrow Transplantation Clinical Trials Network (BMT CTN) 0902 trial. Participants completed the SF-36, a measure of quality of life, prior to transplant and 100 and 180 days post-transplant. Results indicated that attrition resulted in slightly biased overestimates of quality of life but the amount of overestimation remained stable over time. Patients could be grouped into three distinct classes based on physical quality of life: 1) low and stable; 2) average and declining, then stable; and 3) average and stable. Four classes of patients emerged for mental quality of life: 1) low and stable; 2) average, improving, then stable; 3) higher than average (by almost 1 SD) and stable; and 4) average and stable. Taken together, these data provide a more comprehensive understanding of quality of life that can be used to educate HCT recipients and their caregivers. PMID:27538374

Enhanced Polysaccharide Binding and Activity on Linear β-Glucans through Addition of Carbohydrate-Binding Modules to Either Terminus of a Glucooligosaccharide Oxidase

PubMed Central

Foumani, Maryam; Vuong, Thu V.; MacCormick, Benjamin; Master, Emma R.

2015-01-01

The gluco-oligosaccharide oxidase from Sarocladium strictum CBS 346.70 (GOOX) is a single domain flavoenzyme that favourably oxidizes gluco- and xylo- oligosaccharides. In the present study, GOOX was shown to also oxidize plant polysaccharides, including cellulose, glucomannan, β-(1→3,1→4)-glucan, and xyloglucan, albeit to a lesser extent than oligomeric substrates. To improve GOOX activity on polymeric substrates, three carbohydrate binding modules (CBMs) from Clostridium thermocellum, namely CtCBM3 (type A), CtCBM11 (type B), and CtCBM44 (type B), were separately appended to the amino and carboxy termini of the enzyme, generating six fusion proteins. With the exception of GOOX-CtCBM3 and GOOX-CtCBM44, fusion of the selected CBMs increased the catalytic activity of the enzyme (kcat) on cellotetraose by up to 50%. All CBM fusions selectively enhanced GOOX binding to soluble and insoluble polysaccharides, and the immobilized enzyme on a solid cellulose surface remained stable and active. In addition, the CBM fusions increased the activity of GOOX on soluble glucomannan by up to 30 % and on insoluble crystalline as well as amorphous cellulose by over 50 %. PMID:25932926

Effects of the Menopausal Transition on Factors Related to Energy Balance. A MONET group Study

PubMed Central

Karine, Duval; Denis, Prud’homme; Rémi, Rabasa-Lhoret; Irene, Strychar; Martin, Brochu; Jean-Marc, Lavoie; Éric, Doucet

2016-01-01

Objectives Factors that influence weight gain during the menopausal transition are not fully understood. The purpose of this study was to investigate changes in energy expenditure (EE) across the menopausal transition. Methods One hundred and two premenopausal women (age: 49.9 ± 1.9 yrs; BMI: 23.3 ± 2.2 kg/m2) were followed for 5 years. Body composition (DXA), physical activity EE (accelerometer), resting EE and thermic effect of food (indirect calorimetry) were measured annually. Results Total EE decreased significantly over time in postmenopausal women (P < 0.05), which was mostly due to a decrease in physical activity EE (P < 0.05). Although average resting EE remained stable over time in postmenopausal women, a significant increase, over the 5-year period, was noted in women who were in the menopausal transition by year 5 (P < 0.05). Finally, the time spent in moderate physical activity decreased and the time spent in sedentary physical activity increased during the menopausal transition (P < 0.05). Conclusion These results suggest that menopausal transition is accompanied with a decline in EE mainly characterized by a decrease in physical activity EE and a shift to a more sedentary lifestyle. PMID:23422924

Effects of the menopausal transition on energy expenditure: a MONET Group Study.

PubMed

Duval, K; Prud'homme, D; Rabasa-Lhoret, R; Strychar, I; Brochu, M; Lavoie, J-M; Doucet, E

2013-04-01

Factors that influence weight gain during the menopausal transition are not fully understood. The purpose of this study was to investigate changes in energy expenditure (EE) across the menopausal transition. In all, 102 premenopausal women (age: 49.9 ± 1.9 years; body mass index: 23.3 ± 2.2 kg/m(2)) were followed for 5 years. Body composition (dual-energy X-ray absorptiometry), physical activity EE (accelerometer), resting EE and thermic effect of food (indirect calorimetry) were measured annually. Total EE decreased significantly over time in postmenopausal women (P<0.05), which was mostly due to a decrease in physical activity EE (P<0.05). Although average resting EE remained stable over time in postmenopausal women, a significant increase, over the 5-year period, was noted in women who were in the menopausal transition by year 5 (P<0.05). Finally, the time spent in moderate physical activity decreased and the time spent in sedentary physical activity increased during the menopausal transition (P<0.05). These results suggest that menopausal transition is accompanied with a decline in EE mainly characterized by a decrease in physical activity EE and a shift to a more sedentary lifestyle.

Angiotensin I-converting enzyme-inhibitory activity of the Norwegian autochthonous cheeses Gamalost and Norvegia after in vitro human gastrointestinal digestion.

PubMed

Qureshi, T M; Vegarud, G E; Abrahamsen, R K; Skeie, S

2013-02-01

The angiotensin I-converting enzyme (ACE) inhibitory activity of Gamalost cheese, its pH 4.6-soluble fraction, and Norvegia cheese was monitored before and after digestion with human gastric and duodenal juices. Both Gamalost and Norvegia cheeses showed an increased ACE-inhibitory activity during gastrointestinal digestion. However, only Norvegia showed pronounced increased activity after duodenal digestion. More peptides were detected in digested Gamalost compared with digested Norvegia. Most of the peptides in Gamalost were derived from β-casein (CN), some originated from α(s1)-CN, and only a very few originated from α(s2)-CN and κ-CN. In general, the number of peptides increased during gastrointestinal digestion, whereas some peptides were further degraded and disappeared; however, surprisingly, a few peptides remained stable. The aromatic amino acids, such as Tyr, Phe, and Trp; the positively charged amino acids (Arg and Lys); and Leu increased after simulated gastrointestinal digestion of Gamalost and Norvegia. After in vitro gastrointestinal digestion, both Gamalost and Norvegia showed high ACE-inhibitory activity, which may contribute in lowering of mild hypertension. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Characterization and Potential Use of Cuttlefish Skin Gelatin Hydrolysates Prepared by Different Microbial Proteases

PubMed Central

Jridi, Mourad; Lassoued, Imen; Nasri, Rim; Ayadi, Mohamed Ali; Nasri, Moncef

2014-01-01

Composition, functional properties, and in vitro antioxidant activities of gelatin hydrolysates prepared from cuttlefish skin were investigated. Cuttlefish skin gelatin hydrolysates (CSGHs) were obtained by treatment with crude enzyme preparations from Bacillus licheniformis NH1, Bacillus mojavensis A21, Bacillus subtilis A26, and commercial alcalase. All CSGHs had high protein contents, 74.3–78.3%, and showed excellent solubility (over 90%). CSGH obtained by alcalase demonstrated high antioxidant activities monitored by β-carotene bleaching, DPPH radical scavenging, lipid peroxidation inhibition, and reducing power activity. Its antioxidant activity remained stable or increased in a wide range of pH (1–9), during heating treatment (100°C for 240 min) and after gastrointestinal digestion simulation. In addition, alcalase-CSGH was incorporated into turkey meat sausage to determine its effect on lipid oxidation during 35 days of storage period. At 0.5 mg/g, alcalase-CSGH delayed lipid oxidation monitored by TBARS and conjugated diene up to 10 days compared to vitamin C. The results reveal that CSGHs could be used as food additives possessing both antioxidant activity and functional properties. PMID:25025053

Metal-Free Poly-Cycloaddition of Activated Azide and Alkynes toward Multifunctional Polytriazoles: Aggregation-Induced Emission, Explosive Detection, Fluorescent Patterning, and Light Refraction.

PubMed

Wu, Yongwei; He, Benzhao; Quan, Changyun; Zheng, Chao; Deng, Haiqin; Hu, Rongrong; Zhao, Zujin; Huang, Fei; Qin, Anjun; Tang, Ben Zhong

2017-09-01

The metal-free click polymerization (MFCP) of activated alkynes and azides or activated azide and alkynes have been developed into powerful techniques for the construction of polytriazoles without the obsession of metallic catalyst residues problem. However, the MFCP of activated azides and alkynes is rarely applied in preparation of functional polytriazoles. In this paper, soluble multifunctional polytriazoles (PIa and PIb) with high weight-average molecular weights (M w up to 32 000) are prepared via the developed metal-free poly-cycloaddition of activated azide and alkynes in high yields (up to 90%). The resultant PIa and PIb are thermally stable, and show aggregation-induced emission characteristics, enabling their aggregates to detect explosives with superamplification effect. Moreover, thanks to their containing aromatic rings and polar moieties, PIa and PIb exhibit high refractive indices. In addition, they can also be cross-linked upon UV irradiation to generate 2D fluorescent patterning due to their remaining azide groups and containing ester groups. Thus, these multifunctional polytriazoles are potentially applicable in the optoelectronic and sensing fields. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Consequences of lower food intake on the digestive enzymes activities, the energy reserves and the reproductive outcome in Gammarus fossarum.

PubMed

Charron, Laetitia; Geffard, Olivier; Chaumot, Arnaud; Coulaud, Romain; Jaffal, Ali; Gaillet, Véronique; Dedourge-Geffard, Odile; Geffard, Alain

2015-01-01

Digestive enzyme activity is often used as a sensitive response to environmental pollution. However, only little is known about the negative effects of stress on digestive capacities and their consequences on energy reserves and reproduction, although these parameters are important for the maintenance of populations. To highlight if changes in biochemical responses (digestive enzymes and reserves) led to impairments at an individual level (fertility), Gammarus fossarum were submitted to a lower food intake throughout a complete female reproductive cycle (i.e. from ovogenesis to offspring production). For both males and females, amylase activity was inhibited by the diet stress, whereas trypsin activity was not influenced. These results underline similar sensitivity of males and females concerning their digestive capacity. Energy reserves decreased with food starvation in females, and remained stable in males. The number of embryos per female decreased with food starvation. Lower digestive activity in males and females therefore appears as an early response. These results underline the ecological relevance of digestive markers, as they make it possible to anticipate upcoming consequences on reproduction in females, a key biological variable for population dynamics.

Requirement of T-lymphokine-activated killer cell-originated protein kinase for TRAIL resistance of human HeLa cervical cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwon, Hyeok-Ran; Lee, Ki Won; Dong, Zigang

2010-01-01

T-lymphokine-activated killer cell-originated protein kinase (TOPK) appears to be highly expressed in various cancer cells and to play an important role in maintaining proliferation of cancer cells. However, the underlying mechanism by which TOPK regulates growth of cancer cells remains elusive. Here we report that upregulated endogenous TOPK augments resistance of cancer cells to apoptosis induced by tumor necrosis factor-related apoptosis inducing ligand (TRAIL). Stable knocking down of TOPK markedly increased TRAIL-mediated apoptosis of human HeLa cervical cancer cells, as compared with control cells. Caspase 8 or caspase 3 activities in response to TRAIL were greatly incremented in TOPK-depleted cells.more » Ablation of TOPK negatively regulated TRAIL-mediated NF-{kappa}B activity. Furthermore, expression of NF-{kappa}B-dependent genes, FLICE-inhibitory protein (FLIP), inhibitor of apoptosis protein 1 (c-IAP1), or X-linked inhibitor of apoptosis protein (XIAP) was reduced in TOPK-depleted cells. Collectively, these findings demonstrated that TOPK contributed to TRAIL resistance of cancer cells via NF-{kappa}B activity, suggesting that TOPK might be a potential molecular target for successful cancer therapy using TRAIL.« less

Oviductal morphology in relation to hormonal levels in the snapping turtle, Chelydra serpentina.

PubMed

Alkindi, A Y A; Mahmoud, I Y; Woller, M J; Plude, J L

2006-02-01

Microscopic and in situ visual observations were used to relate circulating hormone levels to morphological changes in the oviduct of the snapping turtle Chelydra serpentina throughout the ovarian cycle. Increase in levels of progesterone (P), estradiol (E2) and testosterone (T) levels coincide with an increase in number and growth of endometrial glands, luminal epithelial cells and secretory droplets throughout the oviduct. Testosterone and estradiol levels rose significantly (P < 0.05) after the May-June period and remained high throughout the rest of the summer. Progesterone levels remained stable throughout the summer, with a brief decline in July due to luteolysis. Hormonal values declined significantly (P < 0.001) at the end of the ovarian cycle in the fall. In situ visual observation of fresh oviducts at different stages of gravidity in recently ovulated turtles revealed that proteinaceous like components from the endometrial glands were released into the lumen to form fibers. The morphological features of the oviduct remained active throughout the summer months even though the snapping turtle is a monoclutch species which deposits all the eggs in late-May to mid-June. The high steroid levels correlate with and may be responsible for the secretory activity present throughout the summer and their decline correlates with change to low secretory activity in the fall. Calcium deposition accompanied by morphological changes in luminal cells are suggestive of secretory activity. In the egg-bearing turtles, uterine Ca2+ concentrations measured by flame atomic absorption spectrophotometry revealed significantly higher Ca2+ concentrations (P < 0.001) in eggs with soft shell than eggs without shell. There was a significant increase in calcium granules and proteinaceous fibers in luminal surface of the uterus during the period of eggshelling. This supports the fact that in the snapping turtle like in other reptiles, eggshelling process occurs in the uterus.

Characterization of chitinases of polycentric anaerobic rumen fungi.

PubMed

Novotná, Z; Fliegerová, K; Simůnek, J

2008-01-01

Chitinolytic systems of anaerobic polycentric rumen fungi of genera Orpinomyces and Anaeromyces were investigated in three crude enzyme fractions - extracellular, cytosolic and cell-wall. Endochitinase was found as a dominant enzyme with highest activity in the cytosolic fraction. Endochitinases of both genera were stable at pH 4.5-7.0 with optimum at 6.5. The Orpinomyces endochitinase was stable up to 50 degrees C with an optimum for enzyme activity at 50 degrees C; similarly, Anaeromyces endochitinase was stable up to 40 degrees C with optimum at 40 degrees C. The most suitable substrate for both endochitinases was fungal cell-wall chitin. Enzyme activities were inhibited by Hg(2+) and Mn(2+), and activated by Mg(2+) and Fe(3+). Both endochitinases were inhibited by 10 mmol/L SDS and activated by iodoacetamide.

Structural, stability, and vibrational properties of BinPm clusters

NASA Astrophysics Data System (ADS)

Shen, Wanting; Han, Lihong; Liang, Dan; Zhang, Chunfang; Ruge, Quhe; Wang, Shumin; Lu, Pengfei

2018-04-01

An in-depth investigation is performed on stability mechanisms, electronic and optical properties of III-V semiconductor vapor phases clusters. First principles electronic structure calculations of CAM-B3LYP are performed on neutral BinPm (n + m ≤ 14) clusters. The geometrical evolution of all stable structures remains amorphous as the clusters size increases. Binding energies (BEs), energy gains and highest occupied molecular orbital and lowest unoccupied molecular orbital (HOMO-LUMO) gaps confirm that all four-atom structures of BinPm clusters have more stable optical properties. Orbitals composition and vibrational spectra of stable clusters are analyzed. Our calculations will contribute to the study of diluted bismuth alloys and compounds.

A long-term stable power supply μDMFC stack for wireless sensor node applications

NASA Astrophysics Data System (ADS)

Wu, Z. L.; Wang, X. H.; Teng, F.; Li, X. Z.; Wu, X. M.; Liu, L. T.

2013-12-01

A passive, air-breathing 4-cell micro direct methanol fuel cell (μDMFC) stack is presented featured by a fuel delivery structure for a long-term & stable power supply. The fuel is reserved in a T shape tank and diffuses through the porous diffusion layer to the catalyst at anode. The stack has a maximum power output of 110mW with 3M methanol at room temperature and output a stable power even thought 5% fuel is the remained in reservoir. Its performance decreases less than 3% for 100 hours continuous work. As such, it is believed to be more applicable for powering the wireless sensor nodes.

Synergistic effect of signaling from receptors of soluble platelet agonists and outside-in signaling in formation of a stable fibrinogen-integrin αIIbβ3-actin cytoskeleton complex.

PubMed

Budnik, Ivan; Shenkman, Boris; Savion, Naphtali

2015-01-01

Thrombus formation in the injured vessel wall is a highly complex process involving various blood-born components that go through specific temporal and spatial changes as observed by intravital videomicroscopy. Platelets bind transiently to the developing thrombus and may either become stably incorporated into or disengage from the thrombus. The aim of the present study was to reveal the processes involved in the formation of a stable thrombus. Platelet-rich plasma and washed platelets were studied by the aggregometer. The aggregate stability was challenged by eptifibatide. Platelet Triton-insoluble fraction was prepared and the actin and αIIb content in the cytoskeleton was analyzed by western blot. Maximal actin polymerization is achieved 1min after platelet activation while maximal αIIbβ3-actin cytoskeleton association requires 5 to 10min of activation and fibrinogen-mediated platelet-to-platelet bridging. Thus, actin polymerization is dependent on platelet activation and requires neither αIIbβ3 integrin occupation nor platelet aggregation. Formation of a stable aggregate requires platelet activation for more than 1min, complete increase in actin cytoskeleton fraction and partial association of αIIbβ3 with the actin cytoskeleton. However, direct αIIbβ3 activation is not sufficient for cytoskeleton complex formation. Thus, stable αIIbβ3-fibrinogen interaction, representing stable aggregate, is achieved after more than 1min agonist activation, involving inside-out and outside-in signaling but not after direct integrin activation, involving only outside-in signaling. Formation of a stable fibrinogen-αIIbβ3-actin cytoskeleton complex is the result of the combined effect of platelet stimulation by soluble agonists, activation of αIIbβ3, fibrinogen binding and platelet-to-platelet bridging. Copyright © 2014 Elsevier Ltd. All rights reserved.

Muscle length-dependent contribution of motoneuron Cav1.3 channels to force production in model slow motor unit.

PubMed

Kim, Hojeong

2017-07-01

Persistent inward current (PIC)-generating Ca v 1.3 channels in spinal motoneuron dendrites are thought to be actively recruited during normal behaviors. However, whether and how the activation of PIC channels influences force output of motor unit remains elusive. Here, building a physiologically realistic model of slow motor unit I demonstrated that force production induced by the PIC activation is much smaller for short than lengthened muscles during the regular firing of the motoneuron that transitions from the quiescent state by either a brief current pulse at the soma or a brief synaptic excitation at the dendrites. By contrast, the PIC-induced force potentiation was maximal for short muscles when the motoneuron switched from a stable low-frequency firing state to a stable high-frequency firing state by the current pulse at the soma. Under the synaptic excitation at the dendrites, however, the force could not be potentiated by the transitioning of the motoneuron from a low- to a high-frequency firing state due to the simultaneous onset of PIC at the dendrites and firing at the soma. The strong dependency of the input-output relationship of the motor unit on the neuromodulation and Ia afferent inputs for the PIC channels was further shown under static variations in muscle length. Taken together, these findings suggest that the PIC activation in the motoneuron dendrites may differentially affect the force production of the motor unit, depending not only on the firing state history of the motoneuron and the variation in muscle length but also on the mode of motor activity. NEW & NOTEWORTHY Ca v 1.3 channels in motoneuron dendrites are actively involved during normal motor activities. To investigate the effects of the activation of motoneuron Ca v 1.3 channels on force production, a model motor unit was built based on best-available data. The simulation results suggest that force potentiation induced by Ca v 1.3 channel activation is strongly modulated not only by firing history of the motoneuron but also by length variation of the muscle as well as neuromodulation inputs from the brainstem. Copyright © 2017 the American Physiological Society.

Enzymes from solvent-tolerant microbes: useful biocatalysts for non-aqueous enzymology.

PubMed

Gupta, Anshu; Khare, S K

2009-01-01

Solvent-tolerant microbes are a newly emerging class that possesses the unique ability to thrive in the presence of organic solvents. Their enzymes adapted to mediate cellular and metabolic processes in a solvent-rich environment and are logically stable in the presence of organic solvents. Enzyme catalysis in non-aqueous/low-water media is finding increasing applications for the synthesis of industrially important products, namely peptides, esters, and other trans-esterification products. Solvent stability, however, remains a prerequisite for employing enzymes in non-aqueous systems. Enzymes, in general, get inactivated or give very low rates of reaction in non-aqueous media. Thus, early efforts, and even some recent ones, have aimed at stabilization of enzymes in organic media by immobilization, surface modifications, mutagenesis, and protein engineering. Enzymes from solvent-tolerant microbes appear to be the choicest source for studying solvent-stable enzymes because of their unique ability to survive in the presence of a range of organic solvents. These bacteria circumvent the solvent's toxic effects by virtue of various adaptations, e.g. at the level of the cytoplasmic membrane, by degradation and transformation of solvents, and by active excretion of solvents. The recent screening of these exotic microbes has generated some naturally solvent-stable proteases, lipases, cholesterol oxidase, cholesterol esterase, cyclodextrin glucanotransferase, and other important enzymes. The unique properties of these novel biocatalysts have great potential for applications in non-aqueous enzymology for a range of industrial processes.

New insight in the structural features of haloadaptation in α-amylases from halophilic Archaea following homology modeling strategy: folded and stable conformation maintained through low hydrophobicity and highly negative charged surface

NASA Astrophysics Data System (ADS)

Zorgani, Mohamed Amine; Patron, Kevin; Desvaux, Mickaël

2014-07-01

Proteins from halophilic archaea, which live in extreme saline conditions, have evolved to remain folded, active and stable at very high ionic strengths. Understanding the mechanism of haloadaptation is the first step toward engineering of halostable biomolecules. Amylases are one of the main enzymes used in industry. Yet, no three-dimensional structure has been experimentally resolved for α-amylases from halophilic archaea. In this study, homology structure modeling of α-amylases from the halophilic archaea Haloarcula marismortui, Haloarcula hispanica, and Halalkalicoccus jeotgali were performed. The resulting models were subjected to energy minimization, evaluation, and structural analysis. Calculations of the amino acid composition, salt bridges and hydrophobic interactions were also performed and compared to a set of non-halophilic counterparts. It clearly appeared that haloarchaeal α-amylases exhibited lower propensities for helix formation and higher propensities for coil-forming regions. Furthermore, they could maintain a folded and stable conformation in high salt concentration through highly negative charged surface with over representation of acidic residues, especially Asp, and low hydrophobicity with increase of salt bridges and decrease in hydrophobic interactions on the protein surface. This study sheds some light on the stability of α-amylases from halophilic archaea and provides strong basis not only to understand haloadaptation mechanisms of proteins in microorganisms from hypersalines environments but also for biotechnological applications.

New insight in the structural features of haloadaptation in α-amylases from halophilic Archaea following homology modeling strategy: folded and stable conformation maintained through low hydrophobicity and highly negative charged surface.

PubMed

Zorgani, Mohamed Amine; Patron, Kevin; Desvaux, Mickaël

2014-07-01

Proteins from halophilic archaea, which live in extreme saline conditions, have evolved to remain folded, active and stable at very high ionic strengths. Understanding the mechanism of haloadaptation is the first step toward engineering of halostable biomolecules. Amylases are one of the main enzymes used in industry. Yet, no three-dimensional structure has been experimentally resolved for α-amylases from halophilic archaea. In this study, homology structure modeling of α-amylases from the halophilic archaea Haloarcula marismortui, Haloarcula hispanica, and Halalkalicoccus jeotgali were performed. The resulting models were subjected to energy minimization, evaluation, and structural analysis. Calculations of the amino acid composition, salt bridges and hydrophobic interactions were also performed and compared to a set of non-halophilic counterparts. It clearly appeared that haloarchaeal α-amylases exhibited lower propensities for helix formation and higher propensities for coil-forming regions. Furthermore, they could maintain a folded and stable conformation in high salt concentration through highly negative charged surface with over representation of acidic residues, especially Asp, and low hydrophobicity with increase of salt bridges and decrease in hydrophobic interactions on the protein surface. This study sheds some light on the stability of α-amylases from halophilic archaea and provides strong basis not only to understand haloadaptation mechanisms of proteins in microorganisms from hypersalines environments but also for biotechnological applications.

Synchrony, waves and ripple in spatially coupled Kuramoto oscillators with Mexican hat connectivity.

PubMed

Heitmann, Stewart; Ermentrout, G Bard

2015-06-01

Spatiotemporal waves of synchronized activity are known to arise in oscillatory neural networks with lateral inhibitory coupling. How such patterns respond to dynamic changes in coupling strength is largely unexplored. The present study uses analysis and simulation to investigate the evolution of wave patterns when the strength of lateral inhibition is varied dynamically. Neural synchronization was modeled by a spatial ring of Kuramoto oscillators with Mexican hat lateral coupling. Broad bands of coexisting stable wave solutions were observed at all levels of inhibition. The stability of these waves was formally analyzed in both the infinite ring and the finite ring. The broad range of multi-stability predicted hysteresis in transitions between neighboring wave solutions when inhibition is slowly varied. Numerical simulation confirmed the predicted transitions when inhibition was ramped down from a high initial value. However, non-wave solutions emerged from the uniform solution when inhibition was ramped upward from zero. These solutions correspond to spatially periodic deviations of phase that we call ripple states. Numerical continuation showed that stable ripple states emerge from synchrony via a supercritical pitchfork bifurcation. The normal form of this bifurcation was derived analytically, and its predictions compared against the numerical results. Ripple states were also found to bifurcate from wave solutions, but these were locally unstable. Simulation also confirmed the existence of hysteresis and ripple states in two spatial dimensions. Our findings show that spatial synchronization patterns can remain structurally stable despite substantial changes in network connectivity.

Anticipatory anxiety disrupts neural valuation during risky choice.

PubMed

Engelmann, Jan B; Meyer, Friederike; Fehr, Ernst; Ruff, Christian C

2015-02-18

Incidental negative emotions unrelated to the current task, such as background anxiety, can strongly influence decisions. This is most evident in psychiatric disorders associated with generalized emotional disturbances. However, the neural mechanisms by which incidental emotions may affect choices remain poorly understood. Here we study the effects of incidental anxiety on human risky decision making, focusing on both behavioral preferences and their underlying neural processes. Although observable choices remained stable across affective contexts with high and low incidental anxiety, we found a clear change in neural valuation signals: during high incidental anxiety, activity in ventromedial prefrontal cortex and ventral striatum showed a marked reduction in (1) neural coding of the expected subjective value (ESV) of risky options, (2) prediction of observed choices, (3) functional coupling with other areas of the valuation system, and (4) baseline activity. At the same time, activity in the anterior insula showed an increase in coding the negative ESV of risky lotteries, and this neural activity predicted whether the risky lotteries would be rejected. This pattern of results suggests that incidental anxiety can shift the focus of neural valuation from possible positive consequences to anticipated negative consequences of choice options. Moreover, our findings show that these changes in neural value coding can occur in the absence of changes in overt behavior. This suggest a possible pathway by which background anxiety may lead to the development of chronic reward desensitization and a maladaptive focus on negative cognitions, as prevalent in affective and anxiety disorders. Copyright © 2015 the authors 0270-6474/15/353085-15$15.00/0.

Purification and characterization of a novel endo-β-1,4-glucanases , AfEG22, from the giant snail, Achatina fulica frussac.

PubMed

Teng, Yigang; Yin, Qiuyu; ding, Ming; Zhao, Fukun

2010-10-01

In this study, we confirmed that at least three endo-β-1,4-glucanases existed in the digestive juice of the giant snail, Achatina fulica ferussac, by Congo red staining assay. One of these enzymes, a novel endo-β-1,4-glucanase (AfEG22), was purified 29.5-fold by gel filtration, anion exchange, and hydrophobic interaction chromatography. The carboxymethyl cellulose (CMC) hydrolytic activity of the purified enzyme was 12.3 U/mg protein. The molecular mass of AfEG22 was 22081 Da determined by MALDI-TOF. N-terminal amino acid sequencing revealed a sequence of EQRCTNQGGILKYYNT, which did not have significant homology with any proteins in BLAST database. The optimal pH and temperature for hydrolytic activity toward CMC were pH 4.0 and 50°C, respectively. AfEG22 was stable between pH 3.0 and pH 12.0 when incubated at 4°C for 3 h or at 37°C for 1 h. The enzyme remained more than 80% activity between pH 4.5 and pH 7.0 after incubation at 50°C for 1 h. AfEG22 possessed excellent thermostability as more than 70% activity was remained after incubation at 60°C for 3 h. Substrate specific analysis revealed that AfEG22 was a typical endo-β-1,4-glucanase. This is the first time to report a novel endo-β-1,4-glucanase with high stability from the digestive juice of A. fulica.

Antioxidant and molecular chaperone defences during estivation and arousal in the South American apple snail Pomacea canaliculata.

PubMed

Giraud-Billoud, Maximiliano; Vega, Israel A; Tosi, Martín E Rinaldi; Abud, María A; Calderón, María L; Castro-Vazquez, Alfredo

2013-02-15

The invasive Pomacea canaliculata estivates during periods of drought and should cope with harmful effects of reoxygenation during arousal. We studied thiobarbituric acid reactive substances (TBARS), enzymatic (superoxide dismutase, SOD and catalase, CAT) and non-enzymatic antioxidants (uric acid and reduced glutathione), and heat shock protein expression (Hsc70, Hsp70 and Hsp90) in (1) active control snails, (2) snails after 45 days of estivation, and (3) aroused snails 20 min and (4) 24 h after water exposure, in midgut gland, kidney and foot. Both kidney and foot (but not the midgut gland) showed a TBARS increase during estivation and a decrease after arousal. Tissue SOD and CAT did not change in any experimental groups. Uric acid increased during estivation in all tissues, and it decreased after arousal in the kidney. Allantoin, the oxidation product of uric acid, remained constant in the midgut gland but it decreased in the kidney until 20 min after arousal; however, allantoin levels rose in both kidney and foot 24 h after arousal. Reduced glutathione decreased during estivation and arousal, in both midgut gland and kidney, and it remained constant in the foot. Hsc70 and Hsp70 kidney levels were stable during the activity-estivation cycle and Hsp90 expression decreases during estivation and recovers in the early arousal. In foot, the expression of Hsp70 and Hsp90 was high during activity and estivation periods and disminished after arousal. Results indicate that a panoply of antioxidant and molecular chaperone defences may be involved during the activity-estivation cycle in this freshwater gastropod.

Annual Report: Reaching out to Every Member.

ERIC Educational Resources Information Center

Dillon, Donald W.

1983-01-01

The Music Educators National Conference (MENC) launched a new public relations plan; membership remained relatively stable; division meetings proved successful; and the Music in Our Schools Week campaign completed its best year ever. (RM)

Abnormal-induced theta activity supports early directed-attention network deficits in progressive MCI.

PubMed

Deiber, Marie-Pierre; Ibañez, Vicente; Missonnier, Pascal; Herrmann, François; Fazio-Costa, Lara; Gold, Gabriel; Giannakopoulos, Panteleimon

2009-09-01

The electroencephalography (EEG) theta frequency band reacts to memory and selective attention paradigms. Global theta oscillatory activity includes a posterior phase-locked component related to stimulus processing and a frontal-induced component modulated by directed attention. To investigate the presence of early deficits in the directed attention-related network in elderly individuals with mild cognitive impairment (MCI), time-frequency analysis at baseline was used to assess global and induced theta oscillatory activity (4-6Hz) during n-back working memory tasks in 29 individuals with MCI and 24 elderly controls (EC). At 1-year follow-up, 13 MCI patients were still stable and 16 had progressed. Baseline task performance was similar in stable and progressive MCI cases. Induced theta activity at baseline was significantly reduced in progressive MCI as compared to EC and stable MCI in all n-back tasks, which were similar in terms of directed attention requirements. While performance is maintained, the decrease of induced theta activity suggests early deficits in the directed-attention network in progressive MCI, whereas this network is functionally preserved in stable MCI.

Dynamics of runaway tails with time-dependent sub-Dreicer dc fields in magnetized plasmas

NASA Technical Reports Server (NTRS)

Moghaddam-Taaheri, E.; Vlahos, L.

1987-01-01

The evolution of runaway tails driven by sub-Dreicer time-dependent dc fields in a magnetized plasma are studied numerically using a quasi-linear code based on the Ritz-Galerkin method and finite elements. It is found that the runaway tail maintained a negative slope during the dc field increase. Depending on the values of the dc electric field at t = 0 and the electron gyrofrequency to the plasma frequency ratio the runaway tail became unstable to the anomalous Doppler resonance or remained stable before the saturation of the dc field at some maximum value. The systems that remained stable during this stage became unstable to the anomalous Doppler or the Cerenkov resonances when the dc field was kept at the saturation level or decreased. Once the instability is triggered, the runaway tail is isotropized.

Group size in social-ecological systems.

PubMed

Casari, Marco; Tagliapietra, Claudio

2018-03-13

Cooperation becomes more difficult as a group becomes larger, but it is unclear where it will break down. Here, we study group size within well-functioning social-ecological systems. We consider centuries-old evidence from hundreds of communities in the Alps that harvested common property resources. Results show that the average group size remained remarkably stable over about six centuries, in contrast to a general increase in the regional population. The population more than doubled, but although single groups experienced fluctuations over time, the average group size remained stable. Ecological factors, such as managing forest instead of pasture land, played a minor role in determining group size. The evidence instead indicates that factors related to social interactions had a significant role in determining group size. We discuss possible interpretations of the findings based on constraints in individual cognition and obstacles in collective decision making.

Changes in the respiratory microbiome during acute exacerbations of idiopathic pulmonary fibrosis.

PubMed

Molyneaux, Philip L; Cox, Michael J; Wells, Athol U; Kim, Ho Cheol; Ji, Wonjun; Cookson, William O C; Moffatt, Miriam F; Kim, Dong Soon; Maher, Toby M

2017-02-01

Acute exacerbations of idiopathic pulmonary fibrosis (AE-IPF) have been defined as events of clinically significant respiratory deterioration with an unidentifiable cause. They carry a significant mortality and morbidity and while their exact pathogenesis remains unclear, the possibility remains that hidden infection may play a role. The aim of this pilot study was to determine whether changes in the respiratory microbiota occur during an AE-IPF. Bacterial DNA was extracted from bronchoalveolar lavage from patients with stable IPF and those experiencing an AE-IPF. A hyper-variable region of the 16S ribosomal RNA gene (16S rRNA) was amplified, quantified and pyrosequenced. Culture independent techniques demonstrate AE-IPF is associated with an increased BAL bacterial burden compared to stable disease and highlight shifts in the composition of the respiratory microbiota during an AE-IPF.

Bilateral foveal retinoschisis accompanying unilateral peripheral retinoschisis.

PubMed

Kocak, Nilufer; Ozturk, Taylan A; Kaynak, Suleyman

2014-04-01

X-linked juvenile retinoschisis is a rare hereditary retinal disease characterized by a tangential splitting of the neurosensory retina which may cause early-onset visual impairment. Existence of the retinal neurosensory layer splitting on cross-sectional images of optical coherance tomography (OCT) and the absence of leakage on fluorescein angiography (FA) help confirming the diagnosis. Such diagnostic tests are also helpful in determining the management of the disease. However, most of the retinoschisis cavities remain stable and rarely extend to the posterior pole, many authors suggest laser prophylaxis to avoid the potential risk of retinal detachment due to holes in the outer retinal layer. Herein, we report a case with bilateral foveal retinoschisis accompanying unilateral peripheral retinoschisis who was evaluated with detailed ophthalmologic examination. Visual acuity, fundoscopy, OCT, and FA remained stable in the second year of follow-up after prophylactic argon laser treatment.

Endemism hotspots are linked to stable climatic refugia.

PubMed

Harrison, Susan; Noss, Reed

2017-01-01

Centres of endemism have received much attention from evolutionists, biogeographers, ecologists and conservationists. Climatic stability is often cited as a major reason for the occurrences of these geographic concentrations of species which are not found anywhere else. The proposed linkage between endemism and climatic stability raises unanswered questions about the persistence of biodiversity during the present era of rapidly changing climate. The current status of evidence linking geographic centres of endemism to climatic stability over evolutionary time was examined. The following questions were asked. Do macroecological analyses support such an endemism-stability linkage? Do comparative studies find that endemic species display traits reflecting evolution in stable climates? Will centres of endemism in microrefugia or macrorefugia remain relatively stable and capable of supporting high biological diversity into the future? What are the implications of the endemism-stability linkage for conservation? Recent work using the concept of climate change velocity supports the classic idea that centres of endemism occur where past climatic fluctuations have been mild and where mountainous topography or favourable ocean currents contribute to creating refugia. Our knowledge of trait differences between narrow endemics and more widely distributed species remains highly incomplete. Current knowledge suggests that centres of endemism will remain relatively climatically buffered in the future, with the important caveat that absolute levels of climatic change and species losses in these regions may still be large. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Factors associated with short-term transitions of non-daily smokers: socio-demographic characteristics and other tobacco product use.

PubMed

Wang, Yingning; Sung, Hai-Yen; Yao, Tingting; Lightwood, James; Max, Wendy

2017-05-01

To examine the transitions in smoking status among non-daily smokers who transitioned to daily or former smokers or remained as non-daily smokers during a 12-month period. We analyzed factors associated with these transitions, including the use of cigars and smokeless tobacco (SLT). Secondary data analyses using pooled data from the 2003, 2006/07 and 2010/11 Tobacco Use Supplements to the Current Population Survey (TUS-CPS). United States. Self-respondents aged 18+ who have smoked for more than 5 years and were non-daily smokers 12 months before the interview (n = 13 673, or 14.5% of current smokers). Multinomial logistic regression model to determine the correlates of non-daily to daily, stable non-daily and non-daily to former smoking transitions among non-daily smokers at baseline. The model controlled for socio-demographic factors and the use of cigars and SLT. Of the adults in our sample, 2.6% were non-daily smokers at baseline. Among these, 69.7% remained non-daily smokers (stable non-daily smokers), 18.4% became daily smokers (non-daily to daily smokers) and 11.9% quit smoking (non-daily to former smokers) after 12 months. The non-daily to daily versus stable non-daily smoking transition was less likely among those who were aged 65+ (P = 0.018), male (P < 0.001), Hispanic (P < 0.001), with an income of $25 000-49 999 or ≥$75 000 and current users of SLT (P = 0.003), but more likely among those without a college degree compared with the appropriate reference group. The non-daily to former versus stable non-daily smoking transition was less likely among those aged 25+, male (P = 0.013), non-Hispanic Asian (P = 0.032), without a college degree, widowed/divorced/separated (P = 0.013) or never married (P = 0.011) and current users of cigars (P = 0.003) compared with the appropriate reference group. While more than two-thirds of non-daily smokers in the United States remain as such after 12 months, others become daily smokers or quit. The likelihood of remaining stable non-daily smokers and of transition from non-daily to daily and non-daily to former smokers is associated with socio-demographic factors and current use of cigars and smokeless tobacco. © 2016 Society for the Study of Addiction.

Characterization of Terpenoids from the Root of Ceriops tagal with Antifouling Activity

PubMed Central

Chen, Jun-De; Yi, Rui-Zao; Lin, Yi-Ming; Feng, Dan-Qing; Zhou, Hai-Chao; Wang, Zhan-Chang

2011-01-01

One new dimeric diterpenoid, 8(14)-enyl-pimar-2′(3′)-en-4′(18′)-en-15′(16′)-endolabr- 16,15,2′,3′-oxoan-16-one (1) and five known terpenoids: Tagalsin C (2), Tagalsin I (3), lup-20(29)-ene-3β,28-diol (4), 3-oxolup-20(29)-en-28-oic acid (5) and 28-hydroxylup- 20(29)-en-3-one (6) were isolated from the roots of the mangrove plant Ceriops tagal. Their structures and relative stereochemistry were elucidated by means of extensive NMR, IR and MS analysis. The antifouling activity against larval settlement of the barnacle Balanus albicostatus were evaluated using capsaicin as a positive control. All these terpenoids exhibited antifouling activity against cyprid larvae of the barnacle without significant toxicity. The structure-activity relationship results demonstrated that the order of antifouling activity was diterpenoid (Compound 2) > triterpenoid (Compounds 4, 5 and 6) > dimeric diterpenoid (Compounds 1 and 3). The functional groups on the C-28 position of lupane triterpenoid significantly affect the antifouling activity. The diterpenoid dimmer with two identical diterpenoid subunits might display more potent antifouling activity than one with two different diterpenoid subunits. The stability test showed that Compounds 2, 4, 5 and 6 remained stable over 2-month exposure under filtered seawater. PMID:22072902

Sedimentation Investigation at Masirah Island, Oman.

DTIC Science & Technology

1983-11-01

source of fine-graine"’ rJ-.e.i _. BAt Is .iA Anchorage t-e botton is gravel and coarse sand. C’. rrents are so swift there, fine meterial will not settle...stable and with the proposed pier (a gravity structure to -3 m MLW) and the new intake groin, it will likely remain stable in the future. The volume of...US-BUILT SALTWATER INTAKE GROIN. This shore-normal gravity structure, which affects adjacent shores in .alythe same manner a groin would, was completed

Historical carbon footprinting and implications for sustainability planning: a case study of the Pittsburgh region.

PubMed

Hoesly, Rachel; Blackhurst, Mike; Matthews, H Scott; Miller, Jeffrey F; Maples, Amy; Pettit, Matthew; Izard, Catherine; Fischbeck, Paul

2012-04-17

This study estimates fossil-based CO(2) emissions and energy use from 1900-2000 for Allegheny County, PA. Total energy use and emissions increased from 1900 to 1970, reflecting the significant industrial, economic, and population growth that occurred in Allegheny County. From 1970 to 2000, Allegheny County experienced a 30% decrease in total emissions and energy use from peak values, primarily because of a decline in industrial activity (40% decrease in value added) and the loss of a quarter of its population. Despite these dramatic economic and demographic transitions, per capita emissions remained stable from 1970 to 2000, buoyed by relatively stable or slightly increasing emissions in the commercial and transportation sectors. Allegheny County's history suggests the scale of change needed to achieve local emissions reductions may be significant; given years of major technological, economic, and demographic changes, per capita emissions in 1940 were nearly the same in 2000. Most local governments are planning emissions reductions rates that exceed 1% per year, which deviate significantly from historical trends. Our results suggest additional resources and improved planning paradigms are likely necessary to achieve significant emissions reductions, especially for areas where emissions are still increasing.

Selective extinction of marine plankton at the end of the Mesozoic era: The fossil and stable isotope record

NASA Technical Reports Server (NTRS)

Herman, Y.; Bhattacharya, S. K.

1988-01-01

Floral, faunal and stable isotope evidence in a continuous sequence of latest Cretaceous and earliest Tertiary shallow water marine deposits in the Mangyshlak Peninsula, USSR suggest severe environmental changes at the Cretaceous/Tertiary (K/T) boundary. Time frame is provided by nanno, micro and macrofossils as well as by magnetic stratigraphy and an iridium spike. Oxygen isotopic analyses of the bulk sediments, composed of nanno and microplankton skeletal remains, show a sharp positive spike at the K/T boundary. This shift is primarily attributed to severe cooling possibly accompanied by increased salinities of the surface mixed layer. Floral and faunal extinctions were selective, affecting approximately 90 percent of the warm water calcareous phyto and zooplankton genera in the Tethyan-Paratethyan regions. These highly diverse taxa with many endemic representatives were at the peak of their evolutionary development. Geologic evidence indicates that the terminal Cretaceous temperature decline was coeval with widespread and intense volcanic activity which reached a peak at the close of the Mesozoic Era. Increased acidity temporarily prohibited calcite nucleation of the surface dwelling warm-water plankton. Superimposed upon decreased alkalinity, severe and rapid climatic changes caused the extinction of calcareous phyto and zooplankton.

Hydrothermal growth of two dimensional hierarchical MoS2 nanospheres on one dimensional CdS nanorods for high performance and stable visible photocatalytic H2 evolution

NASA Astrophysics Data System (ADS)

Chava, Rama Krishna; Do, Jeong Yeon; Kang, Misook

2018-03-01

The visible photocatalytic H2 production from water splitting considered as a clean and renewable energy source could solve the problem of greenhouse gas emission from fossil fuels. Despite tremendous efforts, the development of cost effective, highly efficient and more stable visible photocatalysts for splitting of water remains a great challenge. Here, we report the heteronanostructures consisting of hierarchical MoS2 nanospheres grown on 1D CdS nanorods referred to as CdS-MoS2 HNSs as a high performance visible photocatalyst for H2 evolution. The as-synthesized CdS-MoS2 HNSs exhibited ∼11 fold increment of H2 evolution rate when compared to pure CdS nanorods. This remarkable enhanced hydrogen evolution performance can be assigned to the positive synergetic effect from heteronanostructures formed between the CdS and MoS2 components which assist as an electron sink and source for abundant active edge sites and in turn increases the charge separation. This study presents a low-cost visible photocatalyst for solar energy conversion to achieve efficient H2.

The regulation of the Z- and G-box containing promoters by light signaling components, SPA1 and MYC2, in Arabidopsis.

PubMed

Gangappa, Sreeramaiah N; Maurya, Jay P; Yadav, Vandana; Chattopadhyay, Sudip

2013-01-01

Although many transcription factors and regulatory proteins have been identified and functionally characterized in light signaling pathways, photoperception to transcription remains largely fragmented. The Z-box is one of the LREs (Light responsive elements) that plays important role in the regulation of transcription during light-controlled Arabidopsis seedling development. The involvement of photoreceptors in the modulation of the activity of the Z-box containing promoters has been demonstrated. However, the role of downstream signaling components such as SPA1 and MYC2/ZBF1, which are functionally interrelated, remains unknown. In this study, we have investigated the regulation of the Z-box containing synthetic and native promoters by SPA1 and MYC2 by using stable transgenic lines. Our studies suggest that SPA1 negatively regulates the expression of CAB1 native promoter. MYC2 negatively regulates the activity of Z- and/or G-box containing synthetic as well as native promoters irrespective of light quality. Moreover, MYC2 negatively regulates the expression of Z/G-NOS101-GUS even in the darkness. Furthermore, analyses of tissue specific expression in adult plants suggest that MYC2 strongly regulates the activity of Z- and G-box containing promoters specifically in leaves and stems. In roots, whereas MYC2 positively regulates the activity of the Z-box containing synthetic promoter, it does not seem to control the activity of the G-box containing promoters. Taken together, these results provide insights into SPA1- and MYC2-mediated transcriptional regulation of the Z- and G-box containing promoters in light signaling pathways.

Development and Evaluation of Photoprotective O/W Emulsions Containing Hydroalcoholic Extract of Neoglaziovia variegata (Bromeliaceae)

PubMed Central

Souza, Grasielly Rocha; Ferraz, Christiane Adrielly Alves; de Oliveira, Ana Paula; Araújo, Camila de Souza; de Lima-Saraiva, Sarah Raquel Gomes; Gonçalves, Talita Mota; Rolim-Neto, Pedro José; César, Francine Celise Siqueira

2017-01-01

Neoglaziovia variegata is a Bromeliaceae plant species widely found in Brazil with several pharmacological properties, including photoprotective activity. Although herbal-based active ingredients have been applied in cosmetic products, especially for skin treatment, its application in sunscreen formulations remains unexplored. The aim of this work is to evaluate the photoprotective effect of cosmetic formulations containing hydroalcoholic extract of N. variegata (Nv-HA). Initially, the phenolic and flavonoid total content of Nv-HA were determined. The photoprotective activity of Nv-HA was subsequently assessed using a spectrophotometric method. Nv-HA was incorporated in O/W emulsions in the presence or absence of synthetic filters and their photoprotective efficacy was evaluated by spectrophotometric SPF determination. Finally, the stability study of the formulations was performed through the freezing/defrosting method. Nv-HA showed significant phenolic and flavonoids content (61.66 ± 5.14 mg GAE/g and 90.27 ± 5.03 mg CE/g, resp.). Nv-HA showed SPF values of 5.43 ± 0.07 and 11.73 ± 0.04 for the concentrations of 0.5 and 1.0% (v/v), respectively. It was verified that Nv-HA potentiated the photoprotective effect of formulations containing only synthetic filters. Furthermore, the formulations have remained stable at the end of the preliminary stability study. According to the results, it was concluded that Nv-HA can be used as a chemical filter in cosmetic formulations. PMID:28680948

Development and Evaluation of Photoprotective O/W Emulsions Containing Hydroalcoholic Extract of Neoglaziovia variegata (Bromeliaceae).

PubMed

de Oliveira-Júnior, Raimundo Gonçalves; Souza, Grasielly Rocha; Ferraz, Christiane Adrielly Alves; de Oliveira, Ana Paula; Araújo, Camila de Souza; de Lima-Saraiva, Sarah Raquel Gomes; Reis, Silvio Alan Gonçalves Bomfim; Gonçalves, Talita Mota; Rolim, Larissa Araújo; Rolim-Neto, Pedro José; César, Francine Celise Siqueira; Almeida, Jackson Roberto Guedes da Silva

2017-01-01

Neoglaziovia variegata is a Bromeliaceae plant species widely found in Brazil with several pharmacological properties, including photoprotective activity. Although herbal-based active ingredients have been applied in cosmetic products, especially for skin treatment, its application in sunscreen formulations remains unexplored. The aim of this work is to evaluate the photoprotective effect of cosmetic formulations containing hydroalcoholic extract of N. variegata (Nv-HA). Initially, the phenolic and flavonoid total content of Nv-HA were determined. The photoprotective activity of Nv-HA was subsequently assessed using a spectrophotometric method. Nv-HA was incorporated in O/W emulsions in the presence or absence of synthetic filters and their photoprotective efficacy was evaluated by spectrophotometric SPF determination. Finally, the stability study of the formulations was performed through the freezing/defrosting method. Nv-HA showed significant phenolic and flavonoids content (61.66 ± 5.14 mg GAE/g and 90.27 ± 5.03 mg CE/g, resp.). Nv-HA showed SPF values of 5.43 ± 0.07 and 11.73 ± 0.04 for the concentrations of 0.5 and 1.0% (v/v), respectively. It was verified that Nv-HA potentiated the photoprotective effect of formulations containing only synthetic filters. Furthermore, the formulations have remained stable at the end of the preliminary stability study. According to the results, it was concluded that Nv-HA can be used as a chemical filter in cosmetic formulations.

Design and stability study of a paediatric oral solution of methotrexate 2 mg/ml.

PubMed

Vrignaud, Sandy; Briot, Thomas; Launay, Aurélie; Kempf, Marie; Lagarce, Frédéric

2015-06-20

Oral paediatric forms development by pharmaceutical industry is still insufficient. The present study was performed to propose an adapted and pleasant formulation of liquid oral formulation of MTX. The solution is composed of injectable methotrexate, water, Ora Sweet(®) and sodium bicarbonate. After 120 days storage, pH remained stable at about 8 in all formulations, insuring no risk of MTX precipitation. MTX content in solution formulation, determined by high performance liquid chromatography measurements, remained in the specifications of >90% of the initial concentration when stored at 4 and 25°C. Forced degradation of MTX by heat and acidic conditions allowed formation and detection of degradation products by the analytical method. Microbial study of the preparation shows that the solution remains in the specifications during all the storage, or after one sample each week during one month, eventually indicating the microbial properties are not affected by patient use. To conclude, we here propose a new MTX liquid formulation stable for at least 120 days. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of surface stability on core muscle activity for dynamic resistance exercises.

PubMed

Willardson, Jeffrey M; Fontana, Fabio E; Bressel, Eadric

2009-03-01

To compare core muscle activity during resistance exercises performed on stable ground vs. the BOSU Balance Trainer. Twelve trained men performed the back squat, dead lift, overhead press, and curl lifts. The activity of the rectus abdominis, external oblique abdominis, transversus abdominis/internal oblique abdominis, and erector spinae muscles was assessed. Subjects performed each lift under three separate conditions including standing on stable ground with 50% of a 1-RM, standing on a BOSU Balance Trainer with 50% of a 1-RM, and standing on stable ground with 75% of a 1-RM. Significant differences were noted between the stable 75% of 1-RM and BOSU 50% of 1-RM conditions for the rectus abdominis during the overhead press and transversus abdominis/internal oblique abdominis during the overhead press and curl (P < .05). Conversely, there were no significant differences between the stable 75% of 1-RM and BOSU 50% of 1-RM conditions for the external obliques and erector spinae across all lifts examined. Furthermore, there were no significant differences between the BOSU 50% of 1-RM and stable 50% of 1-RM conditions across all muscles and lifts examined. The current study did not demonstrate any advantage in utilizing the BOSU Balance Trainer. Therefore, fitness trainers should be advised that each of the aforementioned lifts can be performed while standing on stable ground without losing the potential core muscle training benefits.

Activated carbon derived from waste coffee grounds for stable methane storage.

PubMed

Kemp, K Christian; Baek, Seung Bin; Lee, Wang-Geun; Meyyappan, M; Kim, Kwang S

2015-09-25

An activated carbon material derived from waste coffee grounds is shown to be an effective and stable medium for methane storage. The sample activated at 900 °C displays a surface area of 1040.3 m(2) g(-1) and a micropore volume of 0.574 cm(3) g(-1) and exhibits a stable CH4 adsorption capacity of ∼4.2 mmol g(-1) at 3.0 MPa and a temperature range of 298 ± 10 K. The same material exhibits an impressive hydrogen storage capacity of 1.75 wt% as well at 77 K and 100 kPa. Here, we also propose a mechanism for the formation of activated carbon from spent coffee grounds. At low temperatures, the material has two distinct types with low and high surface areas; however, activation at elevated temperatures drives off the low surface area carbon, leaving behind the porous high surface area activated carbon.

Activated carbon derived from waste coffee grounds for stable methane storage

NASA Astrophysics Data System (ADS)

Kemp, K. Christian; Baek, Seung Bin; Lee, Wang-Geun; Meyyappan, M.; Kim, Kwang S.

2015-09-01

An activated carbon material derived from waste coffee grounds is shown to be an effective and stable medium for methane storage. The sample activated at 900 °C displays a surface area of 1040.3 m2 g-1 and a micropore volume of 0.574 cm3 g-1 and exhibits a stable CH4 adsorption capacity of ˜4.2 mmol g-1 at 3.0 MPa and a temperature range of 298 ± 10 K. The same material exhibits an impressive hydrogen storage capacity of 1.75 wt% as well at 77 K and 100 kPa. Here, we also propose a mechanism for the formation of activated carbon from spent coffee grounds. At low temperatures, the material has two distinct types with low and high surface areas; however, activation at elevated temperatures drives off the low surface area carbon, leaving behind the porous high surface area activated carbon.

STABLE NITROGEN ISOTOPES AS INDICATORS OF ANTHOPOGENIC ACTIVITIES IN SMALL FRESHWATER SYSTEMS

EPA Science Inventory

Stable nitrogen isotope ratios ( 15N) were measured in fish, mussel, and sediment samples taken from 17 small freshwater sites to examine food chain length and trophic position across sites affected by differing levels of anthropogenic activity. Both shoreline development and fis...

[The Contribution of Vascular Capacity and Blood Volume to Maintain Stable Blood Circulation during General Anesthesia].

PubMed

Shigemi, Kenji

2016-05-01

To maintain proper cardiac preload is one of the most effective procedures for the systemic circulation remaining stable. In particular, the balance between vascular capacity and total blood volume must be maintained within appropriate range by the administration of fluids, blood and/or vasoactive drugs with mean circulatory filling pressure (Pmcf), central venous pressure (CVP) or stroke volume variation (SVV). End-diastolic left ventricular volume (Ved) is theoretically the best index of cardiac preload; however, without transesophageal echocardbalanceiogram we cannot directly monitor Ved during anesthesia. The infused fluid volume remaining in intravascular space, the vascular capacity controlled by autonomic nervous system and/or vasoactive agents, and the unstressed blood volume properly mobilized to excess blood volume are the crucial factors to maintain cardiac output The knowledge of vascular physiology contribute the decision making to manipulate such factors to control blood circulation during general anesthesia. For example, CVP is usually maintained in the narrow range and seems to be stable; however, it must be changed just after the circulatory disturbances, such as acute bleeding, blood transfusion, and fluid infusion, and followed by gradual returning to initial value, because of the solid mechanism to preserve cardiac output

Trends in Serial Measurements of Ultrasound Markers in Second and Third Trimester Down Syndrome Fetuses.

PubMed

Vos, F I; De Jong-Pleij, E A P; Bakker, M; Tromp, E; Bilardo, C M

2015-01-01

To evaluate trends of nasal bone length (NBL), prenasal thickness (PT), nuchal fold (NF), prenasal thickness to nasal bone length (PT-NBL) ratio, and prefrontal space ratio (PFSR), measured serially in second- and third-trimester Down syndrome (DS) fetuses. Prenatal databases were searched for cases of continuing DS pregnancies with serial measurements, taken at least two weeks apart. Trends were plotted on previously reported normal ranges. Serial measurements were available in 25 Down syndrome fetuses. Median gestational age (GA) was 25 weeks; average number of visits per case was 2.44, with a median interval of 39 days between investigations. In DS fetuses, NBL and PT showed fairly stable trends with gestation. PFSR, but especially NF, had a more unpredictable trend. The PT-NBL ratio was the most stable marker, remaining unchanged in 95% of cases. NBL, PT, and NF showed more deviance from the normal range with advancing gestation, but MoM values remained stable. All but two fetuses had ultrasound markers or structural anomalies, especially heart defects. The PT-NBL ratio is the most constant DS marker throughout gestation, following a predictable trend. © 2015 S. Karger AG, Basel.

Increased Plasma Levels of Heme Oxygenase-1 in Human Brucellosis.

PubMed

Chen, Zhe; Zhang, Yu-Xue; Fu, Dong-Wei; Gao, Qing-Feng; Ge, Feng-Xia; Liu, Wei-Hua

2016-08-01

Brucellosis is associated with inflammation and the oxidative stress response. Heme oxygenase-1 (HO-1) is a cytoprotective stress-responsive enzyme that has anti-inflammatory and anti-oxidant effects. Nevertheless, the role of HO-1 in human brucellosis has not yet been studied. The aim of this study was to examine the plasma levels of HO-1 in patients with brucellosis and to evaluate the ability of plasma HO-1 levels as an auxiliary diagnosis, a severity predictor, and a monitor for brucellosis treatments. A total of 75 patients with brucellosis were divided into the acute, subacute, chronic active, and chronic stable groups. An additional 20 volunteers were included as the healthy control group. The plasma HO-1 levels and other laboratory parameters were measured in all groups. Furthermore, the plasma levels of HO-1 in the acute group were compared before and after treatment. The plasma HO-1 levels were considerably increased in the acute (4.97 ± 3.55), subacute (4.98 ± 3.23), and chronic active groups (4.43 ± 3.00) with brucellosis compared to the healthy control group (1.03 ± 0.63) (p < 0.01). In the acute group, the plasma HO-1 levels in the post-treatment group (2.33 ± 2.39) were significantly reduced compared to the pre-treatment group (4.97 ± 3.55) (p < 0.01). On the other hand, the plasma HO-1 levels were higher in the chronic active group (4.43 ± 3.00) than the chronic stable group (2.74 ± 2.23) (p < 0.05). However, the plasma HO-1 levels in the chronic stable group (2.74 ± 2.23) remained higher than the levels in the healthy control group (1.03 ± 0.63) (p < 0.05). The HO-1 levels were positively correlated with the C-reactive protein (CRP) levels in patients with brucellosis (r = 0.707, p < 0.01). The plasma HO-1 levels can reflect patients' brucellosis status and may be used as a supplementary plasma marker for diagnosing brucellosis and monitoring its treatment.

Markers of endothelial dysfunction and severity of hypoxaemia in the Eisenmenger syndrome.

PubMed

de P S Soares, Rosangela; Maeda, Nair Y; Bydlowski, Sérgio P; Lopes, Antonio Augusto

2005-10-01

Endothelial dysfunction has been reported in hypoxaemic patients with the Eisenmenger syndrome, but a direct correlation between levels of endothelial markers and the severity of hypoxaemia has not been explored. With this in mind, we compared the levels in the plasma of tissue-type plasminogen activator, thrombomodulin, and von Willebrand factor in 25 patients with the Eisenmenger syndrome. They had a median age of 31 years, and were divided into 2 groups according to their recent clinical history. Thus, 18 patients were stable, being in functional class II or III, seen as outpatients, and having peripheral saturations of oxygen of 89 plus or minus 5 percent. In contrast, 7 patients were unstable, showing episodes of symptoms placing them in functional class IV, requiring care in hospital, and manifesting saturations of oxygen of 77 plus or minus 5 percent. We were able to follow 12 patients, 8 who were stable and 4 unstable, for 24 months. At baseline, levels of von Willebrand factor were higher in the unstable patients when compared to those who were stable, at 142 plus or minus 29 and 110 plus or minus 25 units per decilitre, respectively (p equal to 0.013). This correlated positively with oxygen desaturation (p less than 0.020). The structural abnormalities also correlated positively with the magnitude of hypoxaemia (p less than 0.020). Levels remained higher in the unstable patients throughout the period of follow-up (p equal to 0.006). Tissue-type plasminogen activator was also increased, at 14.3 plus or minus 8.4 versus 6.5 plus or minus 2.7 nanograms per millilitre in controls (p less than 0.001), whereas thrombomodulin was decreased, with values of 14.4 versus 34.6 nanograms per millilitre in controls (p for median values of less than 0.001). There was no correlation with saturations of oxygen. We conclude that measurement of von Willebrand factor, as compared with tissue-type plasminogen activator and thrombomodulin, will prove a better marker of endothelial response to hypoxaemia in patients with the Eisenmenger syndrome.

Healthcare utilization and costs in adults with stable and uncontrolled epilepsy.

PubMed

Cramer, Joyce A; Wang, Zhixiao J; Chang, Eunice; Powers, Annette; Copher, Ronda; Cherepanov, Dasha; Broder, Michael S

2014-02-01

Despite the availability of numerous antiepileptic drugs (AEDs), some epilepsies remain resistant to treatment. We compared utilization and costs in patients with uncontrolled epilepsy to those with stable epilepsy. Claims data (2007-2009) were used to identify adults with epilepsy requiring additional AED therapy (having uncontrolled epilepsy) and those not requiring additional AED therapy (having stable epilepsy). The date in 2008 on which an additional AED was started was the index date for patients with uncontrolled epilepsy, and a randomly selected date was used for patients with stable epilepsy, whose AED use was unchanged in the preceding year. In the postindex year, all pharmacy and medical claims were used to estimate overall utilization and costs; claims with epilepsy in any diagnosis field were used to estimate epilepsy-related outcomes. Outcomes were adjusted using multivariate analyses. We identified 1536 patients with uncontrolled epilepsy and 8571 patients with stable epilepsy (mean age: 42.8years; female: 48%). Patients with uncontrolled epilepsy had higher comorbidity rates (p<.02). A greater proportion of patients with uncontrolled epilepsy had ≥1 hospitalization or emergency department visit (p<.001). Patients with uncontrolled epilepsy had a greater mean length of hospital stay and more physician office visits (p<.034). After adjustment, the odds of hospitalization (OR: 1.8, any diagnosis; 2.2, epilepsy-related) and emergency department visit (OR: 1.6, any diagnosis; 1.9, epilepsy-related) were greater for patients with uncontrolled epilepsy. Annual overall ($23,238 vs. $13,839) and epilepsy-related ($12,399 vs. $5511) costs were higher in patients with uncontrolled epilepsy and remained higher after adjustment (p<.001). Patients with uncontrolled epilepsy use more services and incur higher costs compared with those with stable epilepsy. Epilepsy-related costs accounted for <50% of the total costs, suggesting that comorbid conditions and/or underidentification of utilization may substantially contribute to costs. © 2013.

Stimulating Fracture Healing in Ischemic Environments: Does Oxygen Direct Stem Cell Fate during Fracture Healing?

PubMed Central

Miclau, Katherine R.; Brazina, Sloane A.; Bahney, Chelsea S.; Hankenson, Kurt D.; Hunt, Thomas K.; Marcucio, Ralph S.; Miclau, Theodore

2017-01-01

Bone fractures represent an enormous societal and economic burden as one of the most prevalent causes of disability worldwide. Each year, nearly 15 million people are affected by fractures in the United States alone. Data indicate that the blood supply is critical for fracture healing; as data indicate that concomitant bone and vascular injury are major risk factors for non-union. However, the various role(s) that the vasculature plays remains speculative. Fracture stabilization dictates stem cell fate choices during repair. In stabilized fractures stem cells differentiate directly into osteoblasts and heal the injury by intramembranous ossification. In contrast, in non-stable fractures stem cells differentiate into chondrocytes and the bone heals through endochondral ossification, where a cartilage template transforms into bone as the chondrocytes transform into osteoblasts. One suggested role of the vasculature has been to participate in the stem cell fate decisions due to delivery of oxygen. In stable fractures, the blood vessels are thought to remain intact and promote osteogenesis, while in non-stable fractures, continual disruption of the vasculature creates hypoxia that favors formation of cartilage, which is avascular. However, recent data suggests that non-stable fractures are more vascularized than stable fractures, that oxygen does not appear associated with differentiation of stem cells into chondrocytes and osteoblasts, that cartilage is not hypoxic, and that oxygen, not sustained hypoxia, is required for angiogenesis. These unexpected results, which contrast other published studies, are indicative of the need to better understand the complex, spatio-temporal regulation of vascularization and oxygenation in fracture healing. This work has also revealed that oxygen, along with the promotion of angiogenesis, may be novel adjuvants that can stimulate healing in select patient populations. PMID:28523266

Scheduled Feeding Alters the Timing of the Suprachiasmatic Nucleus Circadian Clock in Dexras 1-Deficient Mice

PubMed Central

Bouchard-Cannon, Pascale; Cheng, Hai-Ying M.

2013-01-01

Restricted feeding (RF) schedules are potent zeitgebers capable of entraining metabolic and hormonal rhythms in peripheral oscillators in anticipation of food. Behaviorally, this manifests in the form of food anticipatory activity (FAA) in the hours preceding food availability. Circadian rhythms of FAA are thought to be controlled by a food-entrainable oscillator (FEO) outside of the suprachiasmatic nucleus (SCN), the central circadian pacemaker in mammals. Although evidence suggests that the FEO and the SCN are capable of interacting functionally under RF conditions, the genetic basis of these interactions remains to be defined. In this study, using dexras1-deficient (dexras1−/−) mice, the authors examined whether Dexras1, a modulator of multiple inputs to the SCN, plays a role in regulating the effects of RF on activity rhythms and gene expression in the SCN. Daytime RF under 12L:12D or constant darkness (DD) resulted in potentiated (but less stable) FAA expression in dexras1−/− mice compared with wild-type (WT) controls. Under these conditions, the magnitude and phase of the SCN-driven activity component were greatly perturbed in the mutants. Restoration to ad libitum (AL) feeding revealed a stable phase displacement of the SCN-driven activity component of dexras1−/− mice by ~2 h in advance of the expected time. RF in the late night/early morning induced a long-lasting increase in the period of the SCN-driven activity component in the mutants but not the WT. At the molecular level, daytime RF advanced the rhythm of PER1, PER2, and pERK expression in the mutant SCN without having any effect in the WT. Collectively, these results indicate that the absence of Dexras1 sensitizes the SCN to perturbations resulting from restricted feeding. PMID:22928915

Sediment amino acids as indicators of anthropogenic activities and potential environmental risk in Erhai Lake, Southwest China.

PubMed

Ni, Zhaokui; Wang, Shengrui; Zhang, Mianmian

2016-05-01

Total hydrolysable amino acids (THAAs) constitute the most important fraction of labile nitrogen. Anthropogenic activities directly influence various biogeochemical cycles and then accelerate lake ecosystem deterioration. This is the first study that has established the relationship between sediment THAAs and anthropogenic activities using dated sediment cores, and evaluated the possibility of THAAs release at the sediment interface based on changes in environmental conditions in Erhai Lake. The results showed that historical distribution and fractions of THAAs could be divided into three stages: a stable period before the 1970s, a clear increasing period from the 1970s to 1990s, and a gradually steady period that started after the 1990s. The chemical fraction, aromatic and sulfur amino acids (AAs) accounted for only ≤3% of THAAs. Basic AAs accounted for 5-17% of THAAs, and remained at a relatively stable level. However, acidic and neutral AAs, which accounted for 19-44% and 35-69% of THAAs, respectively, were the predominant factors causing THAAs to increase due to rapid agricultural intensification and intensification of contemporary sedimentation of phytoplankton or macrophytes since the 1970s. These trends were closely related to both anthropogenic activities and natural processes, which implied that sediment THAAs could act as an effective indicator that reflects anthropogenic activities and aquatic environmental characteristics. The current contributions of sediment THAAs on TN and TOC were <5% and 1.5%, respectively. However, the dramatic increase in THAAs in the sediment cores indicated that there was a huge potential source of labile nitrogen for the overlying water under certain environmental conditions. Correlation analysis suggested that the release of THAAs was negatively correlated with pH, whereas positively correlated with bacterial number and degree of OM mineralization, which particularly depend on the stability of HFOM. Therefore, the risk of sediment THAAs release might increase when the sediment environment continuously changes. Copyright © 2016 Elsevier B.V. All rights reserved.

Stable Isotope Ratios as Biomarkers of Diet for Health Research

PubMed Central

O’Brien, Diane M.

2016-01-01

Diet is a leading modifiable risk factor for chronic disease, but it remains difficult to measure accurately due to the error and bias inherent in self-reported methods of diet assessment. Consequently there is a pressing need for more objective biomarkers of diet for use in health research. The stable isotope ratios of light elements are a promising set of candidate biomarkers because they vary naturally and reproducibly among foods, and those variations are captured in molecules and tissues with high fidelity. Recent studies have identified valid isotopic measures of short and long-term sugar intake, meat intake, and fish intake in specific populations. These studies provide a strong foundation for validating stable isotopic biomarkers in the general United States population. Approaches to improve specificity for specific foods are needed, for example, by modeling intake using multiple stable isotope ratios, or by isolating and measuring specific molecules linked to foods of interest. PMID:26048703

Effects of constant immigration on the dynamics and persistence of stable and unstable Drosophila populations

PubMed Central

Dey, Snigdhadip; Joshi, Amitabh

2013-01-01

Constant immigration can stabilize population size fluctuations but its effects on extinction remain unexplored. We show that constant immigration significantly reduced extinction in fruitfly populations with relatively stable or unstable dynamics. In unstable populations with oscillations of amplitude around 1.5 times the mean population size, persistence and constancy were unrelated. Low immigration enhanced persistence without affecting constancy whereas high immigration increased constancy without enhancing persistence. In relatively stable populations with erratic fluctuations of amplitude close to the mean population size, both low and high immigration enhanced persistence. In these populations, the amplitude of fluctuations relative to mean population size went down due to immigration, and their dynamics were altered to low-period cycles. The effects of immigration on the population size distribution and intrinsic dynamics of stable versus unstable populations differed considerably, suggesting that the mechanisms by which immigration reduced extinction risk depended on underlying dynamics in complex ways. PMID:23470546

Directional reversals enable Myxococcus xanthus cells to produce collective one-dimensional streams during fruiting-body formation

PubMed Central

Thutupalli, Shashi; Sun, Mingzhai; Bunyak, Filiz; Palaniappan, Kannappan; Shaevitz, Joshua W.

2015-01-01

The formation of a collectively moving group benefits individuals within a population in a variety of ways. The surface-dwelling bacterium Myxococcus xanthus forms dynamic collective groups both to feed on prey and to aggregate during times of starvation. The latter behaviour, termed fruiting-body formation, involves a complex, coordinated series of density changes that ultimately lead to three-dimensional aggregates comprising hundreds of thousands of cells and spores. How a loose, two-dimensional sheet of motile cells produces a fixed aggregate has remained a mystery as current models of aggregation are either inconsistent with experimental data or ultimately predict unstable structures that do not remain fixed in space. Here, we use high-resolution microscopy and computer vision software to spatio-temporally track the motion of thousands of individuals during the initial stages of fruiting-body formation. We find that cells undergo a phase transition from exploratory flocking, in which unstable cell groups move rapidly and coherently over long distances, to a reversal-mediated localization into one-dimensional growing streams that are inherently stable in space. These observations identify a new phase of active collective behaviour and answer a long-standing open question in Myxococcus development by describing how motile cell groups can remain statistically fixed in a spatial location. PMID:26246416

Amyloid Oligomers and Protofibrils, but Not Filaments, Self-Replicate from Native Lysozyme

PubMed Central

2015-01-01

Self-assembly of amyloid fibrils is the molecular mechanism best known for its connection with debilitating human disorders such as Alzheimer’s disease but is also associated with various functional cellular responses. There is increasing evidence that amyloid formation proceeds along two distinct assembly pathways involving either globular oligomers and protofibrils or rigid monomeric filaments. Oligomers, in particular, have been implicated as the dominant molecular species responsible for pathogenesis. Yet the molecular mechanisms regulating their self-assembly have remained elusive. Here we show that oligomers/protofibrils and monomeric filaments, formed along distinct assembly pathways, display critical differences in their ability to template amyloid growth at physiological vs denaturing temperatures. At physiological temperatures, amyloid filaments remained stable but could not seed growth of native monomers. In contrast, oligomers and protofibrils not only remained intact but were capable of self-replication using native monomers as the substrate. Kinetic data further suggested that this prion-like growth mode of oligomers/protofibrils involved two distinct activities operating orthogonal from each other: autocatalytic self-replication of oligomers from native monomers and nucleated polymerization of oligomers into protofibrils. The environmental changes to stability and templating competence of these different amyloid species in different environments are likely to be important for understanding the molecular mechanisms underlying both pathogenic and functional amyloid self-assembly. PMID:24884889

Amyloid oligomers and protofibrils, but not filaments, self-replicate from native lysozyme.

PubMed

Mulaj, Mentor; Foley, Joseph; Muschol, Martin

2014-06-25

Self-assembly of amyloid fibrils is the molecular mechanism best known for its connection with debilitating human disorders such as Alzheimer's disease but is also associated with various functional cellular responses. There is increasing evidence that amyloid formation proceeds along two distinct assembly pathways involving either globular oligomers and protofibrils or rigid monomeric filaments. Oligomers, in particular, have been implicated as the dominant molecular species responsible for pathogenesis. Yet the molecular mechanisms regulating their self-assembly have remained elusive. Here we show that oligomers/protofibrils and monomeric filaments, formed along distinct assembly pathways, display critical differences in their ability to template amyloid growth at physiological vs denaturing temperatures. At physiological temperatures, amyloid filaments remained stable but could not seed growth of native monomers. In contrast, oligomers and protofibrils not only remained intact but were capable of self-replication using native monomers as the substrate. Kinetic data further suggested that this prion-like growth mode of oligomers/protofibrils involved two distinct activities operating orthogonal from each other: autocatalytic self-replication of oligomers from native monomers and nucleated polymerization of oligomers into protofibrils. The environmental changes to stability and templating competence of these different amyloid species in different environments are likely to be important for understanding the molecular mechanisms underlying both pathogenic and functional amyloid self-assembly.

Using Deep UV Raman Spectroscopy to Identify In Situ Microbial Activity

NASA Astrophysics Data System (ADS)

Sapers, H. M.; Wanger, G.; Amend, J.; Orphan, V. J.; Bhartia, R.

2017-12-01

Microbial communities living in close association with lithic substrates play a critical role in biogeochemical cycles. Understanding the interactions between microorganisms and their abiotic substrates requires knowledge of microbial activity. Identifying active cells adhered to complex environmental substrates, especially in low biomass systems, remains a challenge. Stable isotope probing (SIP) provides a means to trace microbial activity in environmental systems. Active members of the community take up labeled substrates and incorporate the labels into biomolecules that can be detected through downstream analyses. Here we show for the first time that Deep UV (248 nm) Raman spectroscopy can differentiate microbial cells labeled with stable isotopes. Previous studies have used Raman spectroscopy with a 532 nm source to identify active bacterial cells by measuring a Raman shift between peaks corresponding to amino acids incorporating 13C compared to controls. However, excitation at 532 nm precludes detection on complex substrates due to high autofluorescence of native minerals. Excitation in the DUV range offers non-destructive imaging on mineral surfaces - retaining critical contextual information. We prepared cultures of E. coli grown in 50 atom% 13C glucose spotted onto Al wafers to test the ability of DUV Raman spectroscopy to differentiate labeled and unlabeled cells. For the first time, we are able to demonstrate a distinct and repeatable shift between cells grown in labeled media and unlabeled media when imaged on Al wafers with DUV Raman spectroscopy. The Raman spectra are dominated by the characteristic Raman bands of guanine. The dominant marker peak for guanine attributed to N7-C8 and C8-N9 ring stretching and C8-H in-plane bending, is visible at 1480 cm-1 in the unlabeled cells and is blue-shifted by 20 wavenumbers to 1461 cm-1 in the labeled cells. The ability of DUV Raman to effectively identify regions containing cells that have incorporated isotopic labels will allow in situ detection of metabolically-targeted active community members on complex natural substrates providing a crucial link between microbial activity and environmental context.

Downhole pressure sensor

NASA Technical Reports Server (NTRS)

Berdahl, C. M.

1980-01-01

Sensor remains accurate in spite of varying temperatures. Very accurate, sensitive, and stable downhole pressure measurements are needed for vaiety of reservoir engineering applications, such as deep petroleum reservoirs, especially gas reservoirs, and in areas of high geothermal gradient.

Reactive attachment disorder of infancy or early childhood

MedlinePlus

... with the child. Counseling may help the caregiver work on problems, such as drug abuse or family violence. Social Services should follow the family to make sure the child remains in a safe, stable environment.

New lipopeptide produced by Corynebacterium aquaticum from a low-cost substrate.

PubMed

Martins, Paola Chaves; Bastos, Cibele Garcia; Granjeiro, Paulo Afonso; Martins, Vilásia Guimarães

2018-04-26

Conventional biosurfactants have high production costs. Therefore, the use of low-cost carbon sources for their production is attractive for industry. The ability to remain stable under various environmental conditions further extends industrial application. Here we aimed to evaluate the stability of a new lipopeptide produced by Corynebacterium aquaticum using fish residue as an unconventional energy source. The biosurfactant was produced using 3% fish residue, 2% of the microorganism, and mineral medium. Biosurfactant characterization was performed by thin layer chromatography (TLC), as well as by testing its infrared, surface tension, emulsifying activity, and ionic character. The stability of the biosurfactant was evaluated by testing its surface tension at a range of temperatures, pH, and saline concentrations, as well as after 6 months of storage. The biosurfactant was characterized as a lipopeptide due to its retention time, which was coincident with the amino acid and lipid chains obtained in the TLC analysis, being confirmed by some regions of absorption verified in the infrared analysis. The surface tension and emulsifying activity of the biosurfactant were 27.8 mN/m and 87.6%, respectively, and showed anionic character. The biosurfactant was stable at temperatures of 20 to 121 °C, in saline concentrations of 1 to 7%, and at pH close to neutrality. Based on our findings, it is possible to use unconventional sources of energy to produce a lipopeptide biosurfactant that can act under various environments.

Leprosy: too complex a disease for a simple elimination paradigm.

PubMed Central

Lockwood, Diana N. J.; Suneetha, Sujai

2005-01-01

Can leprosy be eliminated? This paper considers the question against the background of the WHO programme to eliminate leprosy. In 1991 the World Health Assembly set a target of eliminating leprosy as a public health problem by 2000. Elimination was defined as reaching a prevalence of < 1 case per 10 000 people. The elimination programme has been successful in delivering highly effective antibiotic therapy worldwide. However, despite this advance, new-case detection rates remain stable in countries with the highest rates of endemic leprosy, such as Brazil and India. This suggests that infection has not been adequately controlled by antibiotics alone. Leprosy is perhaps more appropriately classed as a chronic stable disease than as an acute infectious disease responsive to elimination strategies. In many countries activities to control and treat leprosy are being integrated into the general health-care system. This reduces the stigma associated with leprosy. However, leprosy causes long-term immunological complications, disability and deformity. The health-care activities of treating and preventing disabilities need to be provided in an integrated setting. Detecting new cases and monitoring disability caused by leprosy will be a challenge. One solution is to implement long-term surveillance in selected countries with the highest rates of endemic disease so that an accurate estimate of the burden of leprosy can be determined. It is also critical that broad-based research into this challenging disease continues until the problems are truly solved. PMID:15798849

Thermoluminescence dosimetric characteristics on cubic fluoroperovskite single crystal (KMgF3:Eu2+, Ce3+)

NASA Astrophysics Data System (ADS)

Joseph Daniel, D.; Madhusoodanan, U.; Annalakshmi, O.; Jose, M. T.; Ramasamy, P.

2015-07-01

This paper describes investigation of thermoluminescence radiation dosimetry characteristics of Eu2+ doped Potassium Magnesium Fluoride (KMgF3) single crystal co-doped with Ce3+ ions. The perovskite-like KMgF3 polycrystalline compounds were synthesized by standard solid state reaction technique. Phase purity of the synthesized compounds was analyzed by powder X-ray diffraction technique. Single crystals of KMgF3 have been grown from melt by using a vertical Bridgman-Stockbarger method. Thermoluminescence (TL) characteristics of KMgF3 samples doped with Eu2+ and Ce3+ have been studied after β-ray irradiation at room temperature. Order of kinetics (b), activation energy (E), and frequency factor (s) were determined by Chen's method and variable heating rate method. Results show that the TL glow peak of the KMgF3 samples obeys second-order kinetics. Analysis of the main dosimetric peak by using the methods mentioned above revealed that activation energy (E) is about 1.2 eV and the frequency factor (s) is in the range 1010-1011 s-1. The TL glow curve structure of the sample remained stable for higher doses of 90Sr/90Y beta source and it shows linearity up to 180 Gy. The time dependent fading behavior of the TL characteristics has also been investigated and is found to be quite stable over long time duration. The characteristic Eu2+ emissions are observed in the TL emission spectra.

Purification of Ovine Respiratory Complex I Results in a Highly Active and Stable Preparation*

PubMed Central

Letts, James A.; Degliesposti, Gianluca; Fiedorczuk, Karol; Skehel, Mark; Sazanov, Leonid A.

2016-01-01

NADH-ubiquinone oxidoreductase (complex I) is the largest (∼1 MDa) and the least characterized complex of the mitochondrial electron transport chain. Because of the ease of sample availability, previous work has focused almost exclusively on bovine complex I. However, only medium resolution structural analyses of this complex have been reported. Working with other mammalian complex I homologues is a potential approach for overcoming these limitations. Due to the inherent difficulty of expressing large membrane protein complexes, screening of complex I homologues is limited to large mammals reared for human consumption. The high sequence identity among these available sources may preclude the benefits of screening. Here, we report the characterization of complex I purified from Ovis aries (ovine) heart mitochondria. All 44 unique subunits of the intact complex were identified by mass spectrometry. We identified differences in the subunit composition of subcomplexes of ovine complex I as compared with bovine, suggesting differential stability of inter-subunit interactions within the complex. Furthermore, the 42-kDa subunit, which is easily lost from the bovine enzyme, remains tightly bound to ovine complex I. Additionally, we developed a novel purification protocol for highly active and stable mitochondrial complex I using the branched-chain detergent lauryl maltose neopentyl glycol. Our data demonstrate that, although closely related, significant differences exist between the biochemical properties of complex I prepared from ovine and bovine mitochondria and that ovine complex I represents a suitable alternative target for further structural studies. PMID:27672209

Carbon-nanotube-doped Pd-Ni bimetallic three-dimensional electrode for electrocatalytic hydrodechlorination of 4-chlorophenol: Enhanced activity and stability.

PubMed

Wu, Yifan; Gan, Ling; Zhang, Shupeng; Song, Haiou; Lu, Chang; Li, Wentao; Wang, Zheng; Jiang, Bicun; Li, Aimin

2018-08-15

A novel composite bimetallic electrode, palladium-nickel/multi-walled carbon nanotubes/graphite felt (Pd-Ni/MWCNTs/GF), was synthesized for the electrocatalytic hydrodechlorination of 4-chlorophenol (4-CP). GF with a three-dimensional structure was used as the electrode substrate, and doped with MWCNTs, which can improve the GF conductivity and serve as a skeleton for metal loading. Ni and Pd were deposited on the electrode surface stepwise to obtain a well-aligned, highly active and stable Pd-Ni/MWCNTs/GF electrode. The Pd-Ni/MWCNTs/GF cathode showed a high reactivity for the electrocatalytic hydrodechlorination of 4-CP; up to 100% removal of 4-CP was achieved within 30 min, and followed pseudo-first-order kinetics with a rate constant of 0.162 min -1 . Compared with other cathodes, the Pd-Ni/MWCNTs/GF electrode showed superior performance in 4-CP reduction. Excessive current will lower the reaction efficiency and current efficiency because of hydrogen evolution, and acidic solution conditions are more conducive to electrocatalytic reactions. Experiments confirmed that the Ni had a small amount of loss under acidic conditions but remained stable under neutral and alkaline conditions, whereas the loss of Pd for different pH values was constantly low. In cycle tests, the bimetallic electrode exhibits a better reactivity and stability than the single-metal Pd electrode in the long-term. Copyright © 2018 Elsevier B.V. All rights reserved.

Cell line with endogenous EGFRvIII expression is a suitable model for research and drug development purposes.

PubMed

Stec, Wojciech J; Rosiak, Kamila; Siejka, Paulina; Peciak, Joanna; Popeda, Marta; Banaszczyk, Mateusz; Pawlowska, Roza; Treda, Cezary; Hulas-Bigoszewska, Krystyna; Piaskowski, Sylwester; Stoczynska-Fidelus, Ewelina; Rieske, Piotr

2016-05-31

Glioblastoma is the most common and malignant brain tumor, characterized by high cellular heterogeneity. About 50% of glioblastomas are positive for EGFR amplification, half of which express accompanying EGFR mutation, encoding truncated and constitutively active receptor termed EGFRvIII. Currently, no cell models suitable for development of EGFRvIII-targeting drugs exist, while the available ones lack the intratumoral heterogeneity or extrachromosomal nature of EGFRvIII.The reports regarding the biology of EGFRvIII expressed in the stable cell lines are often contradictory in observations and conclusions. In the present study, we use DK-MG cell line carrying endogenous non-modified EGFRvIII amplicons and derive a sub-line that is near depleted of amplicons, whilst remaining identical on the chromosomal level. By direct comparison of the two lines, we demonstrate positive effects of EGFRvIII on cell invasiveness and populational growth as a result of elevated cell survival but not proliferation rate. Investigation of the PI3K/Akt indicated no differences between the lines, whilst NFκB pathway was over-active in the line strongly expressing EGFRvIII, finding further supported by the effects of NFκB pathway specific inhibitors. Taken together, these results confirm the important role of EGFRvIII in intrinsic and extrinsic regulation of tumor behavior. Moreover, the proposed models are stable, making them suitable for research purposes as well as drug development process utilizing high throughput approach.

Cell line with endogenous EGFRvIII expression is a suitable model for research and drug development purposes

PubMed Central

Stec, Wojciech J.; Rosiak, Kamila; Siejka, Paulina; Peciak, Joanna; Popeda, Marta; Banaszczyk, Mateusz; Pawlowska, Roza; Treda, Cezary; Hulas-Bigoszewska, Krystyna; Piaskowski, Sylwester; Stoczynska-Fidelus, Ewelina; Rieske, Piotr

2016-01-01

Glioblastoma is the most common and malignant brain tumor, characterized by high cellular heterogeneity. About 50% of glioblastomas are positive for EGFR amplification, half of which express accompanying EGFR mutation, encoding truncated and constitutively active receptor termed EGFRvIII. Currently, no cell models suitable for development of EGFRvIII-targeting drugs exist, while the available ones lack the intratumoral heterogeneity or extrachromosomal nature of EGFRvIII. The reports regarding the biology of EGFRvIII expressed in the stable cell lines are often contradictory in observations and conclusions. In the present study, we use DK-MG cell line carrying endogenous non-modified EGFRvIII amplicons and derive a sub-line that is near depleted of amplicons, whilst remaining identical on the chromosomal level. By direct comparison of the two lines, we demonstrate positive effects of EGFRvIII on cell invasiveness and populational growth as a result of elevated cell survival but not proliferation rate. Investigation of the PI3K/Akt indicated no differences between the lines, whilst NFκB pathway was over-active in the line strongly expressing EGFRvIII, finding further supported by the effects of NFκB pathway specific inhibitors. Taken together, these results confirm the important role of EGFRvIII in intrinsic and extrinsic regulation of tumor behavior. Moreover, the proposed models are stable, making them suitable for research purposes as well as drug development process utilizing high throughput approach. PMID:27004406

Marital quality and survivorship: slowed recovery for breast cancer patients in distressed relationships.

PubMed

Yang, Hae-Chung; Schuler, Tammy A

2009-01-01

Although marital distress has been implicated in difficulties with adjustment to a breast cancer diagnosis, its long-term effects, especially on physical recovery, are unknown. Longitudinal data from newly diagnosed breast cancer patients (N=100) who were married or cohabiting were used. Patients were assessed after diagnosis and surgery (baseline) and then reassessed every 4 or 6 months for the next 5 years. Women in stable, distressed relationships (n=28) were compared with those in stable, nondistressed relationships (n=72). Stress, health behavior, and health outcomes were examined using mixed-effects modeling. Overall, marital distress was associated with slowed recovery trajectories and poor outcomes. At baseline, both groups had equivalent, high levels of stress, but diverged thereafter. Stress declined more slowly for the Distressed group, and by 5 years it remained significantly higher. Differential reductions in physical activity were also observed. With regard to health, the Distressed group was found to have a slower recovery in performance status and more symptoms/signs of illness and treatment side effects through 3 years. Finally, all the effects were observed above and beyond reductions occurring with depressive symptomatology, which was significantly higher in the Distressed group. Marital distress is not only associated with worse psychologic outcomes for breast cancer survivors, but poorer health and a steeper decline in physical activity. These novel data demonstrate recovery trajectories for breast cancer survivors to be constrained for those also coping with ongoing difficulties in their marriage. Copyright (c) 2008 American Cancer Society.

[Long-term expansion of multipotent mesenchymal stromal cells under reduced oxygen tension].

PubMed

Rylova, Iu V; Buravkova, L B

2013-01-01

We have shown that the decrease in oxygen tension in the culture medium of multipotent mesenchymal stromal cells (MMSCs) results in a short-term reduction in the proportion of CD73(+)-cells in the population, without effecting the number of cells expressing other constitutive surface markers (CD90 and CD105). In this case, the heterogeneity of the cell population declined: large spread cells disappeared. The proliferative activity of MMSCs significantly increased and remained stable in conditions in which the oxygen content was close to the tissue oxygen levels (5% O2). At lower oxygen concentration, proliferative activity of the cells gradually reduced from passages 3-4. The increase in proliferative activity was not accompanied by increased expression of telomerase gene indicateding the alsance of cell transformation. However, genome-wide analysis of MMSC gene expression level revealed changes in expression of cyclins (CCND2 and PCNA), regulatory subunit cyclin-dependent kinase (CKS2) and an inhibitor of cyclin-dependent kinase (CDKN2C), regulating the cell cycle, which is obviously facilitated the increase in the proliferative capacity of cells at lower oxygen tension.

The nature and function of microbial enzymes in subsurface marine sediments

NASA Astrophysics Data System (ADS)

Steen, A. D.; Schmidt, J.

2016-02-01

Isotopic and genomic evidence indicates that marine sediments contain populations of active heterotrophic microorganisms which appear to metabolize old, detrital, apparently recalcitrant organic matter. In surface communities, heterotrophs use extracellular enzymes to access complex organic matter. In subsurface sediments, in which microbial doubling times can be on the order of hundreds or thousands of years, it is not clear whether extracellular enzymes could remain stable and active long enough to constitute a 'profitable' stragtegy for accessing complex organic carbon. Here we present evidence that a wide range of extracellular enzyme are active in subsurface sediments from two different environments: the White Oak River, NC, and deep (up to 80 m) sediments of the Baltic Sea Basin recovered from IODP Expedition 347. In the White Oak River, enzymes from deeper sediments appear to be better-adapted to highly-degraded organic matter than enzymes from surface sediments. In the Baltic Sea, preliminary data suggest that enzymes related to nitrogen acquisition are preferentially expressed. By characterizing the extracellular enzymes present in marine sediments, we hope to achieve a better understanding of the mechanisms that control sedimentary organic matter remineralization and preservation.

Construction of selenium nanoparticles/β-glucan composites for enhancement of the antitumor activity.

PubMed

Jia, Xuewei; Liu, Qingye; Zou, Siwei; Xu, Xiaojuan; Zhang, Lina

2015-03-06

We report on a green procedure for the stabilization of selenium nanoparticles (SeNPs) by a naturally occurring β-glucan with triple helical conformation known as Lentinan (t-LNT) in water after denaturing into single chains (s-LNT) at 140 °C. The results demonstrated that the s-LNT can interact with SeNPs through Se-O-H interaction. Transmission electron microscopy (TEM), energy dispersive X-ray (EDX) spectra, UV/vis, X-ray diffraction (XRD) and dynamic light scattering (DLS) showed that s-LNT coated SeNPs to form a stable nano-composite Se/s-LNT, leading to good dispersion of SeNPs. Especially, the as-prepared Se/s-LNT composite in the solution could remain homogeneous and translucent for 30 days without any precipitates. Different size distribution of SeNPs was prepared by simply controlling the concentrations of selenite sodium and the corresponding reducing agent ascorbic acid. The size effect of SeNPs on anti-tumor activity was revealed that the SeNPs with more evenly particle size distribution show the higher anticancer activity. Copyright © 2014 Elsevier Ltd. All rights reserved.

Functional and genetic screening of acute myeloid leukemia associated with mediastinal germ cell tumor identifies MEK inhibitor as an active clinical agent.

PubMed

Leonard, Jessica T; Raess, Philipp W; Dunlap, Jennifer; Hayes-Lattin, Brandon; Tyner, Jeffrey W; Traer, Elie

2016-03-31

Hematologic malignancies arising in the setting of established germ cell tumors have been previously described and have a dismal prognosis. Identification of targetable mutations and pathway dysregulation through massively parallel sequencing and functional assays provides new approaches to disease management. Herein, we report the case of a 23-year-old male who was diagnosed with a mediastinal germ cell tumor and subsequent acute myeloid leukemia. A shared clonal origin was demonstrated through identification of identical NRAS and TP53 somatic mutations in both malignancies. The patient's leukemia was refractory to standard therapies with short interval relapse. Functional assays demonstrated the patient's blasts to be sensitive to the mitogen-activated protein kinase kinase (MEK) inhibitor trametinib, correlating with the activating NRAS mutation. The patient experienced a sustained partial remission while on trametinib therapy but ultimately suffered relapse of the germ cell tumor. The leukemic clone remained stable and sensitive to trametinib at that time. This case highlights the potential power of combining genetic sequencing and in vitro functional assays with targeted therapies in the treatment of rare diseases.

Accumulation of Succinate in Cardiac Ischemia Primarily Occurs via Canonical Krebs Cycle Activity.

PubMed

Zhang, Jimmy; Wang, Yves T; Miller, James H; Day, Mary M; Munger, Joshua C; Brookes, Paul S

2018-05-29

Succinate accumulates during ischemia, and its oxidation at reperfusion drives injury. The mechanism of ischemic succinate accumulation is controversial and is proposed to involve reversal of mitochondrial complex II. Herein, using stable-isotope-resolved metabolomics, we demonstrate that complex II reversal is possible in hypoxic mitochondria but is not the primary succinate source in hypoxic cardiomyocytes or ischemic hearts. Rather, in these intact systems succinate primarily originates from canonical Krebs cycle activity, partly supported by aminotransferase anaplerosis and glycolysis from glycogen. Augmentation of canonical Krebs cycle activity with dimethyl-α-ketoglutarate both increases ischemic succinate accumulation and drives substrate-level phosphorylation by succinyl-CoA synthetase, improving ischemic energetics. Although two-thirds of ischemic succinate accumulation is extracellular, the remaining one-third is metabolized during early reperfusion, wherein acute complex II inhibition is protective. These results highlight a bifunctional role for succinate: its complex-II-independent accumulation being beneficial in ischemia and its complex-II-dependent oxidation being detrimental at reperfusion. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

A graded catalytic–protective layer for an efficient and stable water-splitting photocathode

DOE PAGES

Gu, Jing; Aguiar, Jeffery A.; Ferrere, Suzanne; ...

2017-01-09

Achieving solar-to-hydrogen efficiencies above 15% is key for the commercial success of photoelectrochemical water splitting devices. While tandem cells can reach those efficiencies, increasing the catalytic activity and long-term stability remains a significant challenge. We show that annealing a bilayer of amorphous titanium dioxide (TiO x) and molybdenum sulfide (MoS x) deposited onto GaInP 2 results in a photocathode with high catalytic activity (current density of 11 mA/cm -2 at 0 V vs. the reversible hydrogen electrode under 1 sun illumination) and stability (retention of 80% of initial photocurrent density over a 20 h durability test) for the hydrogen evolutionmore » reaction. Microscopy and spectroscopy reveal that annealing results in a graded MoS x/MoO x/TiO 2 layer that retains much of the high catalytic activity of amorphous MoS x but with stability similar to crystalline MoS 2. These findings demonstrate the potential of utilizing a hybridized, heterogeneous surface layer as a cost-effective catalytic and protective interface for solar hydrogen production.« less

APOBEC3G Interacts with ssDNA by Two Modes: AFM Studies

NASA Astrophysics Data System (ADS)

Shlyakhtenko, Luda S.; Dutta, Samrat; Banga, Jaspreet; Li, Ming; Harris, Reuben S.; Lyubchenko, Yuri L.

2015-10-01

APOBEC3G (A3G) protein has antiviral activity against HIV and other pathogenic retroviruses. A3G has two domains: a catalytic C-terminal domain (CTD) that deaminates cytidine, and a N-terminal domain (NTD) that binds to ssDNA. Although abundant information exists about the biological activities of A3G protein, the interplay between sequence specific deaminase activity and A3G binding to ssDNA remains controversial. We used the topographic imaging and force spectroscopy modalities of Atomic Force Spectroscopy (AFM) to characterize the interaction of A3G protein with deaminase specific and nonspecific ssDNA substrates. AFM imaging demonstrated that A3G has elevated affinity for deaminase specific ssDNA than for nonspecific ssDNA. AFM force spectroscopy revealed two distinct binding modes by which A3G interacts with ssDNA. One mode requires sequence specificity, as demonstrated by stronger and more stable complexes with deaminase specific ssDNA than with nonspecific ssDNA. Overall these observations enforce prior studies suggesting that both domains of A3G contribute to the sequence specific binding of ssDNA.

APOBEC3G Interacts with ssDNA by Two Modes: AFM Studies.

PubMed

Shlyakhtenko, Luda S; Dutta, Samrat; Banga, Jaspreet; Li, Ming; Harris, Reuben S; Lyubchenko, Yuri L

2015-10-27

APOBEC3G (A3G) protein has antiviral activity against HIV and other pathogenic retroviruses. A3G has two domains: a catalytic C-terminal domain (CTD) that deaminates cytidine, and a N-terminal domain (NTD) that binds to ssDNA. Although abundant information exists about the biological activities of A3G protein, the interplay between sequence specific deaminase activity and A3G binding to ssDNA remains controversial. We used the topographic imaging and force spectroscopy modalities of Atomic Force Spectroscopy (AFM) to characterize the interaction of A3G protein with deaminase specific and nonspecific ssDNA substrates. AFM imaging demonstrated that A3G has elevated affinity for deaminase specific ssDNA than for nonspecific ssDNA. AFM force spectroscopy revealed two distinct binding modes by which A3G interacts with ssDNA. One mode requires sequence specificity, as demonstrated by stronger and more stable complexes with deaminase specific ssDNA than with nonspecific ssDNA. Overall these observations enforce prior studies suggesting that both domains of A3G contribute to the sequence specific binding of ssDNA.

Total amino acid stabilization during cell-free protein synthesis reactions.

PubMed

Calhoun, Kara A; Swartz, James R

2006-05-17

Limitations in amino acid supply have been recognized as a substantial problem in cell-free protein synthesis reactions. Although enzymatic inhibitors and fed-batch techniques have been beneficial, the most robust way to stabilize amino acids is to remove the responsible enzymatic activities by genetically modifying the source strain used for cell extract preparation. Previous work showed this was possible for arginine, serine, and tryptophan, but cysteine degradation remained a major limitation in obtaining high protein synthesis yields. Through radiolabel techniques, we confirmed that cysteine degradation was caused by the activity of glutamate-cysteine ligase (gene gshA) in the cell extract. Next, we created Escherichia coli strain KC6 that combines a gshA deletion with previously described deletions for arginine, serine, and tryptophan stabilization. Strain KC6 grows well, and active cell extract can be produced from it for cell-free protein synthesis reactions. The extract from strain KC6 maintains stable amino acid concentrations of all 20 amino acids in a 3-h batch reaction. Yields for three different proteins improved 75-250% relative to cell-free expression using the control extract.

Mitochondrial flashes regulate ATP homeostasis in the heart

PubMed Central

Wang, Xianhua; Zhang, Xing; Wu, Di; Huang, Zhanglong; Hou, Tingting; Jian, Chongshu; Yu, Peng; Lu, Fujian; Zhang, Rufeng; Sun, Tao; Li, Jinghang; Qi, Wenfeng; Wang, Yanru; Gao, Feng; Cheng, Heping

2017-01-01

The maintenance of a constant ATP level (‘set-point’) is a vital homeostatic function shared by eukaryotic cells. In particular, mammalian myocardium exquisitely safeguards its ATP set-point despite 10-fold fluctuations in cardiac workload. However, the exact mechanisms underlying this regulation of ATP homeostasis remain elusive. Here we show mitochondrial flashes (mitoflashes), recently discovered dynamic activity of mitochondria, play an essential role for the auto-regulation of ATP set-point in the heart. Specifically, mitoflashes negatively regulate ATP production in isolated respiring mitochondria and, their activity waxes and wanes to counteract the ATP supply-demand imbalance caused by superfluous substrate and altered workload in cardiomyocytes. Moreover, manipulating mitoflash activity is sufficient to inversely shift the otherwise stable ATP set-point. Mechanistically, the Bcl-xL-regulated proton leakage through F1Fo-ATP synthase appears to mediate the coupling between mitoflash production and ATP set-point regulation. These findings indicate mitoflashes appear to constitute a digital auto-regulator for ATP homeostasis in the heart. DOI: http://dx.doi.org/10.7554/eLife.23908.001 PMID:28692422

Use of activated carbon to remove undesirable residual amylase from refinery streams

USDA-ARS?s Scientific Manuscript database

In recent years, there has been increased world-wide concern over residual (carry-over)activity of mostly high temperature (HT) and very high temperature (VHT) stable amylases in white, refined sugars from refineries to various food and end-user industries. HT and VHT stable amylases were developed ...

Self-Sealed Bionic Long Microchannels with Thin Walls and Designable Nanoholes Prepared by Line-Contact Capillary-Force Assembly.

PubMed

Lao, Zhao-Xin; Hu, Yan-Lei; Pan, Deng; Wang, Ren-Yan; Zhang, Chen-Chu; Ni, Jin-Cheng; Xu, Bing; Li, Jia-Wen; Wu, Dong; Chu, Jia-Ru

2017-06-01

Long microchannels with thin walls, small width, and nanoholes or irregular shaped microgaps, which are similar to capillaries or cancerous vessels, are urgently needed to simulate the physiological activities in human body. However, the fabrication of such channels remains challenging. Here, microchannels with designable holes are manufactured by combining laser printing with line-contact capillary-force assembly. Two microwalls are first printed by femtosecond laser direct-writing, and subsequently driven to collapse into a channel by the capillary force that arises in the evaporation of developer. The channel can remain stable in solvent due to the enhanced Van der Waals' force caused by the line-contact of microwalls. Microchannels with controllable nanoholes and almost arbitrary patterns can be fabricated without any bonding or multistep processes. As-prepared microchannels, with wall thicknesses less than 1 µm, widths less than 3 µm, lengths more than 1 mm, are comparable with human capillaries. In addition, the prepared channels also exhibit the ability to steer the flow of liquid without any external pump. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Functional impacts of exoskeleton-based rehabilitation in chronic stroke: multi-joint versus single-joint robotic training

PubMed Central

2013-01-01

Stroke is a major cause of disability in the world. The activities of upper limb segments are often compromised following a stroke, impairing most daily tasks. Robotic training is now considered amongst the rehabilitation methods applied to promote functional recovery. However, the implementation of robotic devices remains a major challenge for the bioengineering and clinical community. Latest exoskeletons with multiple degrees of freedom (DOF) may become particularly attractive, because of their low apparent inertia, the multiple actuators generating large torques, and the fact that patients can move the arm in the normal wide workspace. A recent study published in JNER by Milot and colleagues underlines that training with a 6-DOF exoskeleton impacts positively on motor function in patients being in stable phase of recovery after a stroke. Also, multi-joint robotic training was not found to be superior to single-joint robotic training. Although it is often considered that rehabilitation should start from simple movements to complex functional movements as the recovery evolves, this study challenges this widespread notion whose scientific basis has remained uncertain. PMID:24354518

Detectable close-in planets around white dwarfs through late unpacking

NASA Astrophysics Data System (ADS)

Veras, Dimitri; Gänsicke, Boris T.

2015-02-01

Although 25-50 per cent of white dwarfs (WDs) display evidence for remnant planetary systems, their orbital architectures and overall sizes remain unknown. Vibrant close-in (≃1 R⊙) circumstellar activity is detected at WDs spanning many Gyr in age, suggestive of planets further away. Here we demonstrate how systems with 4 and 10 closely packed planets that remain stable and ordered on the main sequence can become unpacked when the star evolves into a WD and experience pervasive inward planetary incursions throughout WD cooling. Our full-lifetime simulations run for the age of the Universe and adopt main-sequence stellar masses of 1.5, 2.0 and 2.5 M⊙, which correspond to the mass range occupied by the progenitors of typical present-day WDs. These results provide (i) a natural way to generate an ever-changing dynamical architecture in post-main-sequence planetary systems, (ii) an avenue for planets to achieve temporary close-in orbits that are potentially detectable by transit photometry and (iii) a dynamical explanation for how residual asteroids might pollute particularly old WDs.

Clinical, biochemical, and hygiene assessment of stabled horses provided continuous or intermittent access to drinking water.

PubMed

Freeman, D A; Cymbaluk, N F; Schott, H C; Hinchcliff, K; McDonnell, S M; Kyle, B

1999-11-01

To compare health, hydration status, and management of stabled pregnant mares provided drinking water continuously or via 1 of 3 intermittent delivery systems. 22 Quarter Horse (QH) or QH-crossbred mares and 18 Belgian or Belgian-crossbred mares (study 1); 24 QH or QH-crossbred mares and 18 Belgian or Belgian-crossbred mares (study 2). Stabled horses were provided water continuously or via 1 of 3 intermittent water delivery systems in 2 study periods during a 2-year period. Body temperature, attitude, appetite, water intake, and urine output were recorded daily. Hygiene of each horse and the stable were assessed weekly. Clinical and biochemical measures of hydration were determined 3 times during each study. Clinical measures of hydration included skin turgor, gum moisture, capillary refill time, and fecal consistency. Biochemical measures of hydration included PCV, plasma total protein concentration, serum osmolality, plasma vasopressin concentration, urine specific gravity, and urine osmolality. All horses remained healthy. Stable hygiene was worse when horses had continuous access to water. Clinical and biochemical measures of hydration did not differ among water delivery systems. Various continuous and intermittent water delivery systems provided adequate amounts of water to stabled horses to maintain health and hydration status. Providing intermittent access to water may be preferable on the basis of stable hygiene.

Adolescent pregnancy: do expectations affect intentions?

PubMed

Stevens-Simon, Catherine; Sheeder, Jeanelle; Beach, Roberta; Harter, Susan

2005-09-01

To establish the relationship between expectations about the effects of childbearing on specific aspects of life and the strength of the desire to remain nonpregnant during adolescence. We hypothesized that the absence of negative childbearing expectations is associated with an increase in the odds that sexually active, inadequately contracepting teenage girls are cognitively susceptible to conception. A racially and ethnically diverse group of 351 nulligravida, inadequately contracepting teenagers was studied. Participants responded to 60 items that asked about their expectation about the effects of becoming pregnant and not doing so. Analyses were performed to determine the factorial structure of the childbearing expectations items and their relationship to cognitive susceptibility to conception, defined as the lack of desire to remain nonpregnant. The analysis yielded a 9-factor solution for the childbearing expectations items. All 9 sub-scales exhibited acceptable reliability coefficients, stable factor patterns, and correlated significantly with the desire to remain nonpregnant. A dose-dependent relationship suggestive of causality was also apparent. In stepwise regression the sub-scales that assessed the anticipated effect of childbearing on future plans, self-esteem, and boyfriend relations remained significant and accounted for 56% of the variance in the desire to remain nonpregnant. The lengthy research instrument was reduced to an 8-item screening tool without loss of psychometric integrity or explanatory power. Childbearing expectations reflect distinct concepts and account for a significant portion of the variance in the desire to remain nonpregnant during adolescence. Thus the 8-item screening tool we validated might be used to formulate a differential diagnosis for the enigmatic behavior of teens who say they do not "want" to become pregnant but do not "mind" doing so enough to try to avoid conceiving by default.

Highly Stable and Active Catalyst for Sabatier Reactions

NASA Technical Reports Server (NTRS)

Hu, Jianli; Brooks, Kriston P.

2012-01-01

Highly active Ru/TiO2 catalysts for Sabatier reaction have been developed. The catalysts have shown to be stable under repeated shutting down/startup conditions. When the Ru/TiO2 catalyst is coated on the engineered substrate Fe-CrAlY felt, activity enhancement is more than doubled when compared with an identically prepared engineered catalyst made from commercial Degussa catalyst. Also, bimetallic Ru-Rh/TiO2 catalysts show high activity at high throughput.

Effects of hypoxia on dopamine concentration and the immune response of White Shrimp ( Litopenaeus vannamei)

NASA Astrophysics Data System (ADS)

Hu, Fawen; Pan, Luqing; Jing, Futao

2009-03-01

Effects of hypoxia on the dopamine concentration and the immune response of White Shrimp Litopenaeus vannamei were studied. The results showed that hypoxia had significant effects on the concentration of dopamine (DA) in the haemolymph, haemocyte count, phenoloxidase activity, phagocytic activity of haemocytes and bacteriolytic and antibacterial activity in the haemolymph ( P<0.05). The concentration of the dopamine in haemolymph reached its maximum in the 3.0 and 1.5 mg L-1 DO groups at 12 h and 6 h, and then returned to normal after 24 h and 12 h, respectively. All immune parameters decreased with the reduction of dissolved oxygen. Total haemocyte count (THC), the hyaline cells and semi-granular cells in the 3.0 mg L-1 DO group became stable after 12 h, while granular cells did so after 24 h. The THC and different haemocyte count (DHC) in the 1.5 mg L-1 DO group became stable after 24 h. Phenoloxidase activity and bacteriolytic activity in the 3.0 and 1.5 mg L-1 DO groups reached their stable levels after 24 h and 12 h respectively, while phagocytic activity and antibacterial activity became stable after 24 and 12, and 36 and 24 h, respectively. It was also indicated that the changes of dopamine concentrations in haemolymph, haemocyte count and phenoloxidase activity were obviously related to the exposure time under hypoxic conditions.

Assessing the applicability of stable isotope analysis to determine the contribution of landfills to vultures' diet.

PubMed

Tauler-Ametller, Helena; Hernández-Matías, Antonio; Parés, Francesc; Pretus, Joan Ll; Real, Joan

2018-01-01

Human activities cause changes to occur in the environment that affect resource availability for wildlife. The increase in the human population of cities has led to a rise in the amount of waste deposited in landfills, installations that have become a new food resource for both pest and threatened species such as vultures. In this study we used stable isotope analysis (SIA) and conventional identification of food remains from Egyptian Vultures (Neophron percnopterus) to assess the applicability of SIA as a new tool for determining the composition of the diets of vultures, a group of avian scavengers that is threatened worldwide. We focused on an expanding Egyptian Vulture population in NE Iberian Peninsula to determine the part played by landfills and livestock in the diet of these species, and aimed to reduce the biases associated with conventional ways of identifying food remains. We compared proportions of diet composition obtained with isotope mixing models and conventional analysis for five main prey. The greatest agreement between the two methods was in the categories 'landfills' and 'birds' and the greatest differences between the results from the two methods were in the categories 'livestock', 'carnivores' and 'wild herbivores'. Despite uncertainty associated to SIA, our results showed that stable isotope analysis can help to distinguish between animals that rely on waste and so present enriched levels of δ 13C than those that feed on the countryside. Indeed, a high proportion of food derived from landfills (nearly 50%) was detected in some breeding pairs. Furthermore we performed GLMM analyses that showed that high values of δ 13C in Egyptian Vulture feathers (a proxy of feeding in landfills) are related with high levels of humanization of territories. This method has the potential to be applied to other threatened vulture species for which there is a lack of information regarding resources they are consuming, being especially important as the main causes of vultures decline worldwide are related to the consumption and availability of food resources.

99mTc-EDDA/HYNIC-TOC scintigraphy in the differential diagnosis of solitary pulmonary nodules.

PubMed

Płachcińska, Anna; Mikołajczak, Renata; Maecke, Helmut R; Michalski, Andrzej; Rzeszutek, Katarzyna; Kozak, Józef; Kuśmierek, Jacek

2004-07-01

Forty-three consecutive patients with solitary pulmonary nodules (SPNs) on chest radiographs were studied scintigraphically after administration of the somatostatin analogue (99m)Tc-EDDA/HYNIC-TOC. The objective of the study was to assess the usefulness of the procedure for differentiation of SPNs as malignant or benign. The administered activity was 740-925 MBq, and a single-photon emission computed tomography imaging technique was employed. Verification of the nodule aetiology was based on histology or cytology and bacteriology. A stable tumour size on chest radiography for at least 3 years was accepted as an additional criterion of benignity. In 29 patients, nodules were found to be malignant. The diagnoses included ten adenocarcinomas, five squamous cell carcinomas, two large cell carcinomas, six non-small cell lung cancers without specification of the more detailed morphology, two small cell lung cancers, two typical carcinoids and two metastatic tumours (leiomyosarcoma and malignant melanoma). In 14 patients the following benign tumours were diagnosed: four tuberculomas, one other granuloma, three hamartomas, one non-specific inflammatory infiltrate, one abscess, one peripheral carcinoid with the morphological characteristics of a benign tumour, one ectopic lesion of thyroid tissue and two benign tumours of unspecified aetiology with a stable size over 3 and 5 years respectively. Positive scintigraphic results were obtained in 26 of the 29 patients (90%) with malignant SPNs; among these, 24 of the 25 (96%) cases of primary pulmonary carcinoma yielded positive results. The remaining two false negative cases were the metastatic tumours, liposarcoma and melanoma. Of the 14 benign lesions, ten (71%) did not accumulate the radiopharmaceutical. The remaining four benign tumours that were visible on scintigrams comprised one tuberculoma, one hamartoma, one abscess and one case in which the diagnosis could not be established (the tumour had a stable size over 3 years). In conclusion, scintigraphy with (99m)Tc-EDDA/HYNIC-TOC appears to be an effective procedure for differentiation between malignant and benign SPNs. A fully credible assessment of the clinical efficacy of this procedure requires further study in a larger number of patients.

Influence of time, storage temperature and freeze/thaw cycles on the activity of digestive enzymes from gilthead sea bream (Sparus aurata).

PubMed

Solovyev, Mikhail; Gisbert, Enric

2016-10-01

In this study, we tested the effects of long-term storage (2 years) at -20 °C and short-term storage (several hours) in ice and freeze/thaw cycles on the activities of pancreatic, gastric and intestinal (brush border and cytosolic) digestive enzymes in a teleost fish species. The results revealed a significant lose in activity of pancreatic (trypsin, chymotrypsin, total alkaline proteases and α-amylase) and intestinal cytosolic (leucine-alanine peptidase) enzymes between 140 and 270 days of storage at -20 °C, whereas in contrast, the activity of all the assayed brush border enzymes remained constant during the first 2 years of storage at -20 °C. During short-term storage conditions, the most stable enzymes assayed were those of the enterocytes of the brush border, which did not show any change in activity after being held for 5 h in ice. Five freezing and thawing cycles did not affect the activity of the intestinal brush border enzymes and the cytosolic ones, whereas the activity of trypsin, α-amylase and bile-salt-activated lipase was significantly affected by the number of freezing and thawing cycles. No changes in pepsin activity were found in samples exposed to 1 and 2 freezing and thawing cycles.

The nature and treatment of stuttering as revealed by fMRI A within- and between-group comparison.

PubMed

Neumann, Katrin; Euler, Harald A; von Gudenberg, Alexander Wolff; Giraud, Anne-Lise; Lanfermann, Heinrich; Gall, Volker; Preibisch, Christine

2003-01-01

This article reviews some of our recent functional magnetic resonance imaging (fMRI) studies of stuttering. Using event-related fMRI experiments, we investigated brain activation during speech production. Results of three studies comparing persons who stutter (PWS) and persons who do not stutter (PWNS) are outlined. Their findings point to a region in the right frontal operculum (RFO) that was consistently implicated in stuttering. During overt reading and before fluency shaping therapy, PWS showed higher and more distributed neuronal activation than PWNS. Immediately after therapy differential activations were even more distributed and left sided. They extended to frontal, temporal, and parietal regions, anterior cingulate, insula, and putamen. These over-activations were slightly reduced and again more right sided two years after therapy. Left frontal deactivations remained stable over two years of observation, and therefore possibly indicate a dysfunction. After therapy, we noted higher activations in persons who stutter moderately than in those who stutter severely. These activations might reflect patterns of compensation. We discuss why these findings suggest that fluency-inducing techniques might synchronize a disturbed signal transmission between auditory, speech motor planning, and motor areas. The reader will learn about and be able to: (1) identify regions of brain activations and deactivations specific for PWS; (2) describe brain activation changes induced by fluency shaping therapy; and (3) discuss the correlation between stuttering severity and brain activation.

Regulation of intestinal mucosa guanylate cyclase by hemin, heme and protoporphyrin IX.

PubMed

elDeib, M M; Parker, C D; White, A A

1987-04-02

Mg2+-dependent activity of intestinal brush border guanylate cyclase was stimulated 4-5-fold by 50-100 microM hemin. Higher concentrations were inhibitory. In the presence of 25% dimethyl sulfoxide, which stimulated activity 9-times, 50 microM hemin further increased activity 1.7-fold. However, when activity was stimulated 32-fold by the Escherichia coli heat-stable enterotoxin, or 26-fold by Lubrol PX, hemin produced only concentration-dependent inhibition. The first type of activation was more sensitive to hemin than the second. Reduction of hemin by dithiothreitol eliminated stimulation of basal activity, while inhibition of Lubrol PX-stimulated activity remained. Protoporphyrin IX also had no effect on basal activity, however, it inhibited enterotoxin- and Lubrol PX-stimulated activities similarly, but only to half the extent of hemin. Substitution of Mn2+ for Mg2+ elevated basal activity 15-fold, and this Mn2+-dependent activity was inhibited by hemin. Mn2+-dependent activity was stimulated (43%) by enterotoxin, however, the stimulated activity was more sensitive to hemin inhibition than the basal Mn2+-dependent activity and both inhibition curves were congruent above 50 microM hemin. Hemin inhibition of Lubrol PX-stimulated activity was much less with Mn2+ than with Mg2+. These results were interpreted as suggesting two sites of hemin inhibition; on an inhibitory regulator and on the enzyme. We also found that the secretory effect of enterotoxin in the suckling mouse bioassay was reduced 56% by the oral administration of hemin.

Within-Breath Control of Genioglossal Muscle Activation in Humans: Effect of Sleep-Wake State

PubMed Central

Fogel, Robert B; Trinder, John; Malhotra, Atul; Stanchina, Michael; Edwards, Jill K; Schory, Karen E; White, David P

2003-01-01

Pharyngeal dilator muscles are clearly important in the pathogenesis of obstructive sleep apnoea syndrome. Substantial data support the role of a local negative pressure reflex in modifying genioglossal activation across inspiration during wakefulness. Using a model of passive negative pressure ventilation, we have previously reported a tight relationship between varying intrapharyngeal negative pressures and genioglossal muscle activation (GGEMG) during wakefulness. In this study, we used this model to examine the slope of the relationship between epiglottic pressure (Pepi) and GGEMG, during stable NREM sleep and the transition from wakefulness to sleep. We found that there was a constant relationship between negative epiglottic pressure and GGEMG during both basal breathing (BB) and negative pressure ventilation (NPV) during wakefulness (slope GGEMG/Pepi 1.86 ± 0.3 vs. 1.79 ± 0.3 arbitrary units (a.u.) cmH2O−1). However, while this relationship remained stable during NREM sleep during BB, it was markedly reduced during NPV during sleep (2.27 ± 0.4 vs. 0.58 ± 0.1 a.u. cmH2O−1). This was associated with a markedly higher pharyngeal airflow resistance during sleep during NPV. At the transition from wakefulness to sleep there was also a greater reduction in peak GGEMG seen during NPV than during BB. These data suggest that while the negative pressure reflex is able to maintain GGEMG during passive NPV during wakefulness, this reflex is unable to do so during sleep. The loss of this protective mechanism during sleep suggests that an airway dependent upon such mechanisms (as in the patient with sleep apnoea) will be prone to collapse during sleep. PMID:12807995

fMRI characterisation of widespread brain networks relevant for behavioural variability in fine hand motor control with and without visual feedback.

PubMed

Mayhew, Stephen D; Porcaro, Camillo; Tecchio, Franca; Bagshaw, Andrew P

2017-03-01

A bilateral visuo-parietal-motor network is responsible for fine control of hand movements. However, the sub-regions which are devoted to maintenance of contraction stability and how these processes fluctuate with trial-quality of task execution and in the presence/absence of visual feedback remains unclear. We addressed this by integrating behavioural and fMRI measurements during right-hand isometric compression of a compliant rubber bulb, at 10% and 30% of maximum voluntary contraction, both with and without visual feedback of the applied force. We quantified single-trial behavioural performance during 1) the whole task period and 2) stable contraction maintenance, and regressed these metrics against the fMRI data to identify the brain activity most relevant to trial-by-trial fluctuations in performance during specific task phases. fMRI-behaviour correlations in a bilateral network of visual, premotor, primary motor, parietal and inferior frontal cortical regions emerged during performance of the entire feedback task, but only in premotor, parietal cortex and thalamus during the stable contraction period. The trials with the best task performance showed increased bilaterality and amplitude of fMRI responses. With feedback, stronger BOLD-behaviour coupling was found during 10% compared to 30% contractions. Only a small subset of regions in this network were weakly correlated with behaviour without feedback, despite wider network activated during this task than in the presence of feedback. These findings reflect a more focused network strongly coupled to behavioural fluctuations when providing visual feedback, whereas without it the task recruited widespread brain activity almost uncoupled from behavioural performance. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Hexavalent chromium induces malignant transformation of human lung bronchial epithelial cells via ROS-dependent activation of miR-21-PDCD4 signaling

PubMed Central

Divya, Sasidharan Padmaja; Turcios, Lilia; Roy, Ram Vinod; Hitron, John Andrew; Wang, Lei; Kim, Donghern; Dai, Jin; Asha, Padmaja; Zhang, Zhuo; Shi, Xianglin

2016-01-01

Hexavalent chromium [Cr(VI)] is a well-known human carcinogen associated with an increased risk of lung cancer. However, the mechanisms underlying Cr(VI)-induced carcinogenesis remain unclear. MicroRNA-21 (miR-21) is a key regulator of oncogenic processes. Studies have shown that miR-21 exerts its oncogenic activity by targeting the tumor suppressor gene programmed cell death 4 (PDCD4). The present study examined the role of miR-21-PDCD4 signaling in Cr(VI)-induced cell transformation and tumorigenesis. Results showed that Cr(VI) induces ROS generation in human bronchial epithelial (BEAS-2B) cells. Chronic exposure to Cr(VI) is able to cause malignant transformation in BEAS-2B cells. Cr(VI) caused a significant increase of miR-21 expression associated with an inhibition of PDCD4 expression. Notably, STAT3 transcriptional activation by IL-6 is crucial for the Cr(VI)-induced miR-21 elevation. Stable knockdown of miR-21 or overexpression of PDCD4 in BEAS-2B cells significantly reduced the Cr(VI)-induced cell transformation. Furthermore, the Cr(VI) induced inhibition of PDCD4 suppressed downstream E-cadherin protein expression, but promoted β-catenin/TCF-dependent transcription of uPAR and c-Myc. We also found an increased miR-21 level and decreased PDCD4 expression in xenograft tumors generated with chronic Cr(VI)-exposed BEAS-2B cells. In addition, stable knockdown of miR-21 and overexpression of PDCD4 reduced the tumorogenicity of chronic Cr(VI)-exposed BEAS-2B cells in nude mice. Taken together, these results demonstrate that the miR-21-PDCD4 signaling axis plays an important role in Cr(VI)-induced carcinogenesis. PMID:27323401

Stable isotope evidence for increasing dietary breadth in the European mid-Upper Paleolithic

PubMed Central

Richards, Michael P.; Pettitt, Paul B.; Stiner, Mary C.; Trinkaus, Erik

2001-01-01

New carbon and nitrogen stable isotope values for human remains dating to the mid-Upper Paleolithic in Europe indicate significant amounts of aquatic (fish, mollusks, and/or birds) foods in some of their diets. Most of this evidence points to exploitation of inland freshwater aquatic resources in particular. By contrast, European Neandertal collagen carbon and nitrogen stable isotope values do not indicate significant use of inland aquatic foods but instead show that they obtained the majority of their protein from terrestrial herbivores. In agreement with recent zooarcheological analyses, the isotope results indicate shifts toward a more broad-spectrum subsistence economy in inland Europe by the mid-Upper Paleolithic period, probably associated with significant population increases. PMID:11371652

Stable isotope evidence for increasing dietary breadth in the European mid-Upper Paleolithic.

PubMed

Richards, M P; Pettitt, P B; Stiner, M C; Trinkaus, E

2001-05-22

New carbon and nitrogen stable isotope values for human remains dating to the mid-Upper Paleolithic in Europe indicate significant amounts of aquatic (fish, mollusks, and/or birds) foods in some of their diets. Most of this evidence points to exploitation of inland freshwater aquatic resources in particular. By contrast, European Neandertal collagen carbon and nitrogen stable isotope values do not indicate significant use of inland aquatic foods but instead show that they obtained the majority of their protein from terrestrial herbivores. In agreement with recent zooarcheological analyses, the isotope results indicate shifts toward a more broad-spectrum subsistence economy in inland Europe by the mid-Upper Paleolithic period, probably associated with significant population increases.

Comparison of hamstring and quadriceps femoris electromyographic activity between men and women during a single-limb squat on both a stable and labile surface.

PubMed

Youdas, James W; Hollman, John H; Hitchcock, James R; Hoyme, Gregory J; Johnsen, Jeremiah J

2007-02-01

The purpose of this study was to determine if women are quadriceps dominant and men are hamstring dominant during the performance of a partial single-leg squat (SLS) on both a stable and labile ground surface against body weight resistance. Thirty healthy participants (15 men and 15 women) performed an SLS on both a stable surface and a 6.4-cm-thick vinyl pad. Surface electromyographic (EMG) recordings were obtained from the quadriceps femoris and hamstring muscles during the extension phase of the SLS. Statistical analysis revealed that women produced 14% more EMG activity (p = 0.04) in their quadriceps than the men during the SLS on a stable surface, whereas the men generated 18% more EMG activity (p = 0.04) in their hamstrings than the women during the SLS on a labile surface. Additionally, we found a statistically significant sex effect (p = 0.048) for the hamstring/quadriceps (H/Q) EMG ratio, which was 2.25 and 0.62, respectively, for men and women on the stable surface and 2.52 and 0.71, respectively, on the labile surface. We concluded that women are quadriceps dominant and men are hamstring dominant during the performance of SLS against body weight resistance on either a stable or labile surface condition. During an SLS, men showed an H/Q ratio approximately 3.5 times larger than their female counterparts, suggesting that men activate their hamstrings more effectively than women during an SLS. According to our data, the SLS may not be an ideal exercise for activating the hamstring muscles in women without additional neuromuscular training techniques, because women are quadriceps dominant during the SLS.

Application of thoracic endovascular aortic repair (TEVAR) in treating dwarfism with Stanford B aortic dissection: A case report.

PubMed

Qiu, Jian; Cai, Wenwu; Shu, Chang; Li, Ming; Xiong, Qinggen; Li, Quanming; Li, Xin

2018-04-01

To apply thoracic endovascular aortic repair (TEVAR) to treat dwarfism complicated with Stanford B aortic dissection. In this report, we presented a 63-year-old male patient of dwarfism complicated with Stanford B aortic dissection successfully treated with TEVAR. He was diagnosed with dwarfism complicated with Stanford B aortic dissection. After conservative treatment, the male patient underwent TEVAR at 1 week after hospitalization. After operation, he presented with numbness and weakness of his bilateral lower extremities, and these symptoms were significantly mitigated after effective treatment. At 1- and 3-week after TEVAR, the aorta status was maintained stable and restored. The patient obtained favorable clinical prognosis and was smoothly discharged. During subsequent follow-up, he remained physically stable. TEVAR is probably an option for treating dwarfism complicated with Stanford B aortic dissection, which remains to be validated by subsequent studies with larger sample size.

Effect of 11 September 2001 terrorist attacks in the USA on suicide in areas surrounding the crash sites.

PubMed

Claassen, Cynthia A; Carmody, Thomas; Stewart, Sunita M; Bossarte, Robert M; Larkin, Gregory L; Woodward, Wayne A; Trivedi, Madhukar H

2010-05-01

The terrorist attacks in the USA on 11 September 2001 affected suicide rates in two European countries, whereas overall US rates remained stable. The effect on attack site rates, however, has not been studied. To examine post-attack suicide rates in areas surrounding the three airline crash sites. Daily mortality rates were modelled using time series techniques. Where rate change was significant, both duration and geographic scope were analysed. Around the World Trade Center, post-attack 180-day rates dropped significantly (t = 2.4, P = 0.0046), whereas comparison condition rates remained stable. No change was observed for Pentagon or Flight 93 crash sites. The differential effect by site suggests that proximity may be less important that other event characteristics. Both temporal and geographic aspects of rate fluctuation after sentinel events appear measurable and further analyses may contribute valuable knowledge about how sociological forces affect these rates.

Bilateral foveal retinoschisis accompanying unilateral peripheral retinoschisis

PubMed Central

Kocak, Nilufer; Ozturk, Taylan A; Kaynak, Suleyman

2014-01-01

X-linked juvenile retinoschisis is a rare hereditary retinal disease characterized by a tangential splitting of the neurosensory retina which may cause early-onset visual impairment. Existence of the retinal neurosensory layer splitting on cross-sectional images of optical coherance tomography (OCT) and the absence of leakage on fluorescein angiography (FA) help confirming the diagnosis. Such diagnostic tests are also helpful in determining the management of the disease. However, most of the retinoschisis cavities remain stable and rarely extend to the posterior pole, many authors suggest laser prophylaxis to avoid the potential risk of retinal detachment due to holes in the outer retinal layer. Herein, we report a case with bilateral foveal retinoschisis accompanying unilateral peripheral retinoschisis who was evaluated with detailed ophthalmologic examination. Visual acuity, fundoscopy, OCT, and FA remained stable in the second year of follow-up after prophylactic argon laser treatment. PMID:23571248

A novel mode of enhancer evolution: The Tal1 stem cell enhancer recruited a MIR element to specifically boost its activity

PubMed Central

Smith, Aileen M.; Sanchez, Maria-Jose; Follows, George A.; Kinston, Sarah; Donaldson, Ian J.; Green, Anthony R.; Göttgens, Berthold

2008-01-01

Altered cis-regulation is thought to underpin much of metazoan evolution, yet the underlying mechanisms remain largely obscure. The stem cell leukemia TAL1 (also known as SCL) transcription factor is essential for the normal development of blood stem cells and we have previously shown that the Tal1 +19 enhancer directs expression to hematopoietic stem cells, hematopoietic progenitors, and to endothelium. Here we demonstrate that an adjacent region 1 kb upstream (+18 element) is in an open chromatin configuration and carries active histone marks but does not function as an enhancer in transgenic mice. Instead, it boosts activity of the +19 enhancer both in stable transfection assays and during differentiation of embryonic stem (ES) cells carrying single-copy reporter constructs targeted to the Hprt locus. The +18 element contains a mammalian interspersed repeat (MIR) which is essential for the +18 function and which was transposed to the Tal1 locus ∼160 million years ago at the time of the mammalian/marsupial branchpoint. Our data demonstrate a previously unrecognized mechanism whereby enhancer activity is modulated by a transposon exerting a “booster” function which would go undetected by conventional transgenic approaches. PMID:18687876

North Atlantic Storm Activity During the Younger Dryas

NASA Astrophysics Data System (ADS)

Toomey, M.

2015-12-01

The risks posed to cities along the Eastern Seaboard by a potential intensification of tropical cyclone activity over the coming decades remain poorly constrained, in part, due to a lack of available storm proxy records that extend beyond the relatively stable climates of the late Holocene. Previous work in the Bahamas shows that coarse-grained, high-energy event layers in carbonate bank margin sediments: (1) closely track recent historic hurricane events and (2) that the sensitivity of this proxy may be less affected by the deglacial changes in sea level that have limited our ability to reconstruct past hurricane activity using overwash records from back-barrier beach settings. Here we present a record of storm triggered turbidite deposition from a suite of well dated (e.g. Lynch-Stieglitz et al., 2011, Paleoceanography) jumbo piston cores taken offbank (300-500 mbsl) the Dry Tortugas, Florida, that spans abrupt transitions in North Atlantic sea surface temperature and thermohaline circulation during the Younger Dryas (12.9 - 11.5 kyr BP). This record, along with General Circulation Model output (TraCE: NCAR-CGD), indicates strong hurricane activity may have occurred along Southeastern US coasts through this interval despite considerably colder North Atlantic SSTs.

Compatibility and activity of enoxaparin sodium in 0.9% sodium chloride injection for 48 hours.

PubMed

Mewborn, A L; Kessler, J M; Joyner, K A

1996-01-15

The stability of enoxaparin sodium in 0.9% sodium chloride injection in polyvinyl chloride (PVC) containers was studied. Triplicate solutions of 120 mg (1.2 mL) of enoxaparin (as the sodium salt) and 98.8 mL of 0.9% sodium chloride injection were prepared in 250-mL PVC containers and stored at room temperature (20-22 degrees C). Samples were taken immediately after preparation and at 0.25, 0.5, 0.75, 1, 4, 12, 16, 24, and 48 hours. Inspections for color change and precipitation were performed with a clarity inspection station and a magnifying glass. Samples of the three admixtures were evaluated in duplicate for pharmacologic activity by an automated coagulation heparin assay. Throughout the 48-hour study period, the enoxaparin admixtures were free of color change, evolution of gas, and precipitates. The pharmacologic activity of enoxaparin in the PVC containers remained > 94% of the initial measured activity for 48 hours. Enoxaparin 1.2 mg/mL (as the sodium salt) in 0.9% sodium chloride injection in PVC containers was stable for up to 48 hours at 20-22 degrees C.

Characterization of a Thermostable d-Stereospecific Alanine Amidase from Brevibacillus borstelensis BCS-1

PubMed Central

Baek, Dae Heoun; Kwon, Seok-Joon; Hong, Seung-Pyo; Kwak, Mi-Sun; Lee, Mi-Hwa; Song, Jae Jun; Lee, Seung-Goo; Yoon, Ki-Hong; Sung, Moon-Hee

2003-01-01

A gene encoding a new thermostable d-stereospecific alanine amidase from the thermophile Brevibacillus borstelensis BCS-1 was cloned and sequenced. The molecular mass of the purified enzyme was estimated to be 199 kDa after gel filtration chromatography and about 30 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, indicating that the enzyme could be composed of a hexamer with identical subunits. The purified enzyme exhibited strong amidase activity towards d-amino acid-containing aromatic, aliphatic, and branched amino acid amides yet exhibited no enzyme activity towards l-amino acid amides, d-amino acid-containing peptides, and NH2-terminally protected amino acid amides. The optimum temperature and pH for the enzyme activity were 85°C and 9.0, respectively. The enzyme remained stable within a broad pH range from 7.0 to 10.0. The enzyme was inhibited by dithiothreitol, 2-mercaptoethanol, and EDTA yet was strongly activated by Co2+ and Mn2+. The kcat/Km for d-alaninamide was measured as 544.4 ± 5.5 mM−1 min−1 at 50°C with 1 mM Co2+. PMID:12571020

Economic conditions and suicide rates in New York City.

PubMed

Nandi, Arijit; Prescott, Marta R; Cerdá, Magdalena; Vlahov, David; Tardiff, Kenneth J; Galea, Sandro

2012-03-15

Extant analyses of the relation between economic conditions and population health were often based on annualized data and were susceptible to confounding by nonlinear time trends. In the present study, the authors used generalized additive models with nonparametric smoothing splines to examine the association between economic conditions, including levels of economic activity in New York State and the degree of volatility in the New York Stock Exchange, and monthly rates of death by suicide in New York City. The rate of suicide declined linearly from 8.1 per 100,000 people in 1990 to 4.8 per 100,000 people in 1999 and then remained stable from 1999 to 2006. In a generalized additive model in which the authors accounted for long-term and seasonal time trends, there was a negative association between monthly levels of economic activity and rates of suicide; the predicted rate of suicide was 0.12 per 100,000 persons lower when economic activity was at its peak compared with when it was at its nadir. The relation between economic activity and suicide differed by race/ethnicity and sex. Stock market volatility was not associated with suicide rates. Further work is needed to elucidate pathways that link economic conditions and suicide.

Identification and Functional Characterization of a Stable, Centrally Active Derivative of the Neurotensin (8–13) Fragment as a Potential First-in-Class Analgesic

PubMed Central

Hughes, Francis M.; Shaner, Brooke E.; May, Lisa A.; Zotian, Lyndsay; Brower, Justin O.; Woods, R. Jeremy; Cash, Michael; Morrow, Dustin; Massa, Fabienne; Mazella, Jean; Dix, Thomas A.

2010-01-01

The neurotensin hexapapetide fragment NT(8–13) is a potent analgesic when administered directly to the central nervous system, but does not cross the blood brain barrier. A total of 43 novel derivatives of NT(8–13) were evaluated with one, ABS212 (1), being most active in four rat models of pain when administered peripherally. Compound 1 binds to human neurotensin receptors 1 and 2 with IC50s of 10.6 and 54.2 nM, respectively and tolerance to the compound in a rat pain model did not develop after 12 days of daily administration. When administered peripherally, serum levels and neurotensin receptor binding potency of 1 peaked within 5 min and returned to baseline within 90–120 min, however analgesic activity remained near maximum for >240 min. This could be due to its metabolism into an active fragment; however, all 4- and 5-mer hydrolysis products were inactive. This pharmacokinetic/pharmacodynamic dichotomy is discussed. Compound 1 is a candidate for development as a first-in-class analgesic. PMID:20481538