Structure and specificity of T cell receptor gamma/delta on major histocompatibility complex antigen-specific CD3+, CD4-, CD8- T lymphocytes.

Analyses of TCR-bearing murine and human T cells have defined a unique subpopulation of T cells that express the TCR-gamma/delta proteins. The specificity of TCR-gamma/delta T cells and their role in the immune response have not yet been elucidated. Here we examine alloreactive TCR-gamma/delta T cell lines and clones that recognize MHC-encoded antigens. A BALB/c nu/nu (H-2d)-derived H-2k specific T cell line and derived clones were both cytolytic and released lymphokines after recognition of a non-classical H-2 antigen encoded in the TL region of the MHC. These cells expressed the V gamma 2/C gamma 1 protein in association with a TCR-delta gene product encoded by a Va gene segment rearranged to two D delta and one J delta variable elements. A second MHC-specific B10 nu/nu (H-2b) TCR-gamma/delta T cell line appeared to recognize a classical H-2D-encoded MHC molecule and expressed a distinct V gamma/C gamma 4-encoded protein. These data suggest that many TCR-gamma/delta-expressing T cells may recognize MHC-linked antigens encoded within distinct subregions of the MHC. The role of MHC-specific TCR-gamma/delta cells in immune responses and their immunological significance are discussed

Energy density of foods and beverages in the Australian food supply: influence of macronutrients and comparison to dietary intake.

OBJECTIVES: The energy density (ED) of the diet is considered an important determinant of total energy intake and thus energy balance and weight change. We aimed to compare relationships between ED and macronutrient content in individual food and beverage items as well as population diet in a typical Western country. DESIGN: Nutrient data for 3673 food items and 247 beverage items came from the Australian Food and Nutrient database (AusNut). Food and beverage intake data came from the 1995 Australian National Nutrition Survey (a 24-h dietary recall survey in 13 858 people over the age of 2). Relationships between ED and macronutrient and water content were analysed by linear regression with 95% prediction bands. RESULTS: For both individual food items and population food intake, there was a positive relationship between ED and percent energy as fat and negative relationships between ED and percent energy as carbohydrate and percent water by weight. In all cases, there was close agreement between the slopes of the regression lines between food items and dietary intake. There were no clear relationships between ED and macronutrient content for beverage items. Carbohydrate (mostly sucrose) contributed 91, 47, and 25% of total energy for sugar-based, fat-based, and alcohol-based beverages respectively. CONCLUSIONS: The relationship between ED and fat content of foods holds true across both population diets and individual food items available in the food supply in a typical Western country such as Australia. As high-fat diets are associated with a high BMI, population measures with an overall aim of reducing the ED of diets may be effective in mediating the growing problem of overweight and obesity

Food and Feeding Habits of Catfish (Synodontis nigrita Cuvier And Valenciennes) In River Rima, Sokoto, Nigeria

The food and feeding habits of Synodontis nigrita (Cuvier and Valenciennes) from River Rima were studied. One hundred and three samples were collected from September to October 2006. The stomachs were analyzed using frequency of occurrence method. The mean total length of the samples was 13.04±2.55SD, mean total weight 30.42±21.84SD and mean gut length 39.57±8.92SD. The fish is an omnivore, feeding mainly on phytoplankton, zooplankton, detritus, plant tissues, insects, crustaceans and insect parts. The presence of detritus in almost all the stomachs indicated bottom feeding. The fish gut length was 3 times the body length

A survey of farmers’ perceptions and management strategies of the sweet potato weevil in Homa bay county, Kenya

Sweet potato (Ipomoea batatas L.) is one of the most widely grown root cropsworldwide. In Africa, it is grown in small plots by poorer farmers. Production of thecrop is extremely low in Kenya as compared to other African countries due to theexistence of common insect pests. Sweet potato weevil (Cylas spp.) is known as thebiggest pit fall for production and productivity of the crop in the country. This studysought to determine the opinion of sweet potato farmers concerning sweet potatoresistance to Cylas spp. and determine control strategies employed by sweet potatofarmers in managing the pest. The study also sought to determine the sweet potatoproduction constraints faced by the farmers in Homa Bay County, Kenya. The studywas conducted using a Participatory Rural Appraisal approach in which 269 farmers inthe County were interviewed on the sweet potato varieties with field resistance to Cylasspp., the crops’ production constraints (with emphasis on damage by Cylas spp.) andfarmers’ control strategies in regard to the weevil. Data were also collected from thefarmers whose sample size was determined using the table on sample size selection andstandardization equation. Data were analysed using descriptive statistical techniquesthat were frequencies, percentages and standard errors. The study established thatmajority of the farmers from Rachuonyo (89.7%) and Ndhiwa (91.9%) were not awareof any variety that had field resistance to Cylas spp. However, 10.5% of the farmers inRachuonyo and 8.1% of the farmers in Ndhiwa identified nine varieties which haveshown relative field resistance to root damage by Cylas spp. The varieties that wereidentified to be resistant to Cylas spp. by farmers in Rachuonyo were Kalamb Nyerere,Tombra, Sinia, Odinga, Kemb 10, Wera and Zapallo. However, the varieties that wereidentified to be resistant to Cylas spp. by farmers in Ndhiwa were Amina, Mugandeand Ndege Oyiejo. Further, the findings revealed that Cylas spp. was the mostproblematic pest by 90.3% and 96.8% of households in Rachuonyo and Ndhiwa,respectively. Majority (64.5%) of the farmers in Ndhiwa did not use any methods tomanage Cylas spp. However, farmers in Rachuonyo (26.2%) and Ndhiwa (15.3%)preferred re-ridging during weeding as a management strategy in regard to Cylas spp.These findings reiterate the importance of the sweet potato weevil in rural sweet potatofarming systems and thus innovative management strategies are necessary.Key words: Sweet potato, control strategies, Cylas spp., resistance, pest, variety,constraint

Photosensitization of ZnO Crystals with Iodide-Capped PbSe Quantum Dots

© 2016 American Chemical Society. Lead selenide (PbSe) quantum dots (QDs) are an attractive material for application in photovoltaic devices due to the ability to tune their band gap, efficient multiple exciton generation, and high extinction coefficients. However, PbSe QDs are quite unstable to oxidation in air. Recently there have been multiple studies detailing postsynthetic halide treatments to stabilize lead chalcogenide QDs. We exploit iodide-stabilized PbSe QDs in a model QD-sensitized solar cell configuration where zinc oxide (ZnO) single crystals are sensitized using cysteine as a bifunctional linker molecule. Sensitized photocurrents stable for >1 h can be measured in aqueous KI electrolyte that is usually corrosive to QDs under illumination. The spectral response of the sensitization extended out to 1700 nm, the farthest into the infrared yet observed. Hints of the existence of multiple exciton generation and collection as photocurrent, as would be expected in this system, are speculated and discussed

The Children’s Hospital of Philadelphia Family Partners Program: Promoting child and family-centered care in pediatrics

Involving Family Advisory Councils in decisions that impact pediatric healthcare demonstrates hospitals’ commitment to child- and family-centered care. Yet, reliance on advisors as the sole source of family input has several limitations: infrequent meetings impedes the council’s capacity to address emerging concerns in a timely manner; feedback obtained from a small number of highly-engaged family members may not represent the perspectives of “typical” patients and families; advisors provide feedback in a reactive manner and are generally not equitably involved in problem identification or the initial development of solutions. In recognition of the need to strengthen and advance family partnerships, the Children’s Hospital of Philadelphia made significant structural and operational changes to advance and expand the family centered care model. The Family Partners Program, a component of the broader family centered care portfolio, is a centralized institution-wide resource that enables practitioners, researchers, and healthcare leaders to collaborate with trained family representatives. This paper describes the Family Partner Program infrastructure; approaches to recruiting, onboarding, training, and mentoring parents and caregivers; and the many ways that Family Partners promote the core principles of child- and family-centeredness in clinical care, quality improve, and research contexts

Reduced metabolism supports hypoxic flight in the high-flying bar-headed goose (Anser indicus)

This is the final version. Available on open access from eLife Sciences Publications via the DOI in this recordThe bar-headed goose is famed for migratory flight at extreme altitude. To better understand the physiology underlying this remarkable behavior, we imprinted and trained geese, collecting the first cardiorespiratory measurements of bar-headed geese flying at simulated altitude in a wind tunnel. Metabolic rate during flight increased 16-fold from rest, supported by an increase in the estimated amount of O2 transported per heartbeat and a modest increase in heart rate. The geese appear to have ample cardiac reserves, as heart rate during hypoxic flights was not higher than in normoxic flights. We conclude that flight in hypoxia is largely achieved via the reduction in metabolic rate compared to normoxia. Arterial Po2 was maintained throughout flights. Mixed venous PO2 decreased during the initial portion of flights in hypoxia, indicative of increased tissue O2 extraction. We also discovered that mixed venous temperature decreased during flight, which may significantly increase oxygen loading to hemoglobin.National Science FoundationNatural Sciences and Engineering Research Council of Canada (NSERC

Disruption of Escherichia coli Nissle 1917 K5 Capsule Biosynthesis, through Loss of Distinct kfi genes, Modulates Interaction with Intestinal Epithelial Cells and Impact on Cell Health

Escherichia coli Nissle 1917 (EcN) is among the best characterised probiotics, with a proven clinical impact in a range of conditions. Despite this, the mechanisms underlying these "probiotic effects" are not clearly defined. Here we applied random transposon mutagenesis to identify genes relevant to the interaction of EcN with intestinal epithelial cells. This demonstrated mutants disrupted in the kfiB gene, of the K5 capsule biosynthesis cluster, to be significantly enhanced in attachment to Caco-2 cells. However, this phenotype was distinct from that previously reported for EcN K5 deficient mutants (kfiC null mutants), prompting us to explore further the role of kfiB in EcN:Caco-2 interaction. Isogenic mutants with deletions in kfiB (EcNΔkfiB), or the more extensively characterised K5 capsule biosynthesis gene kfiC (EcNΔkfiC), were both shown to be capsule deficient, but displayed divergent phenotypes with regard to impact on Caco-2 cells. Compared with EcNΔkfiC and the EcN wild-type, EcNΔkfiB exhibited significantly greater attachment to Caco-2 cells, as well as apoptotic and cytotoxic effects. In contrast, EcNΔkfiC was comparable to the wild-type in these assays, but was shown to induce significantly greater COX-2 expression in Caco-2 cells. Distinct differences were also apparent in the pervading cell morphology and cellular aggregation between mutants. Overall, these observations reinforce the importance of the EcN K5 capsule in host-EcN interactions, but demonstrate that loss of distinct genes in the K5 pathway can modulate the impact of EcN on epithelial cell health

Analysis of the genetic diversity of selected East African sweet potato (Ipomea batatas [L.] Lam.) accessions using microsatellite markers

Sweet potato (Ipomea batatas [L.] Lam.) is an economically important crop in East Africa chiefly grown by small holder farmers. Sharing of vines for planting is a very common occurrence among these farmers and eventually varieties are given local names, making it hard to trace the original pedigree. It is therefore important to characterise the sweet potato germplasm for purposes of breeding and germplasm conservation. In this study, 68 sweet potato accessions were evaluated for diversity using 12 microsatellite markers. The genetic relationship of the germplasm was evaluated using the Jaccard’s coefficient for dissimilarity analysis, unweighted pair group method with arithmetic means (UPGMA) tree and principal component analysis (PCoA) on DARwin software, while summary statistics was done using PowerMarker and Popgene softwares. The polymorphic information content of the markers ranged from 0.1046 for markers J67b and J67 to 0.3671 for marker J1809a, with a mean value of 0.2723. The total number of alleles amplified was 21. The major allele frequency ranged from 0.5882 for marker JB1809a to 0.9412 for markers J67b and J67c. Cluster analysis divided the accessions into four major clusters. Principle component analysis divided the accession into four groups which were different from those by cluster analysis. This study was able to identify several distinct accessions as well as a few possible duplicate accessions that overlapped on the cluster analysis.Key words: Sweet potato, cluster analysis, genetic diversity, principal component analysis, Simple SequenceRepeats