Requirement for the SLP-76 adaptor GADS in T cell development

GADS is an adaptor protein implicated in CD3 signaling because of its ability to link SLP-76 to LAT. A GADS-deficient mouse was generated by gene targeting, and the function of GADS in T cell development and activation was examined. GADS- CD4-CD8- thymocytes exhibited a severe block in proliferation but still differentiated into mature T cells. GADS- thymocytes failed to respond to CD3 cross-linking in vivo and were impaired in positive and negative selection. Immunoprecipitation experiments revealed that the association between SLP-76 and LAT was uncoupled in GADS- thymocytes. These observations indicate that GADS is a critical adaptor for CD3 signaling.     

Carotenoid accumulation and characterization of cDNAs encoding phytoene synthase and phytoene desaturase in garlic (Allium sativum)

Phytoene synthase (PSY) and phytoene desaturase (PDS), which catalyze the first and second steps of the carotenoid biosynthetic pathway, respectively, are key enzymes for the accumulation of carotenoids in many plants. We isolated 2 partial cDNAs encoding PSY (AsPSY-1 and AsPSY-2) and a partial cDNA encoding PDS (AsPDS) from Allium sativum. They shared high sequence identity and conserved motifs with other orthologous genes. Quantitative real-time PCR analysis was used to determine the expression levels of AsPSY1, AsPSY2, and AsPDS in the bulbils, scapes, leaves, stems, bulbs, and roots of garlic. High-performance liquid chromatography demonstrated that carotenoids were not biosynthesized in the underground organs (roots and bulbs), but were very abundant in the photosynthetic organs (leaves) of A. sativum. A significantly higher amount of β-carotene (73.44 μg·g(-1)) was detected in the leaves of A. sativum than in the other organs.     

Rural income generation through improving crop-based pig production systems in Vietnam: Diagnostics,interventions, and dissemination

Sweetpotato-pig production is an important system that generates income, utilizes unmarketable crops, and provides manure for soil fertility maintenance. This system is widely practiced from Asia to Africa, with many local variations. Within this system, pigs are generally fed a low nutrient-dense diet, yielding low growth rates and low economic efficiency. Our project in Vietnam went through a process of situation analysis, participatory technology development (PTD), and scaling up over a seven-year period to improve sweetpotato-pig production and to disseminate developed technologies. The situation analysis included a series of pig production assessments in several provinces in northern and southern Vietnam, and pig supply-market chain identification was conducted in 13 provinces. The analysis of these studies informed the project of the following: (1) appropriate locations for our activities; (2) seasonal available feedstuff and farmers feeding practices; (3) market fluctuation and requirements; and (4) feeding and management improvement needs based on which the subsequent phase of PTD was designed. The PTD involved a limited number of farmers participating in sweetpotato varietal selection, sweetpotato root and vine silage processing, seasonal feeding combination, and pig feeding with balanced crop-feed diet and silage. Six years of multi-location and multi-season sweetpotato selection resulted in a few promising varieties that yielded up to 75% more dry matter and have since been formally released. The most significant results of silage processing and feeding trials include improved growth, higher feeding efficiency, increased year-round local feedstuff, and considerable labor reduction from eliminated cooking and vine cutting. Once these technologies were developed, a farmer-to-farmer training model was designed for scaling up the adoption and impact. Farmer trainers from seven communes in seven provinces received training in these technologies. In turn, they undertook the responsibility of training other farmers on sweetpotato selection, processing, and feeding. An impact study was also administered to monitor and evaluate (M&E) the dissemination process and to document the impact of the new technologies and farmer-to-farmer training model on pig growth and farmer income generation. The results showed that both participating and non-participating farmers have taken up the technologies, although the former demonstrates higher rates of adoption than the latter. The participants also generated more income and saved more labor from the adoption of the technologies. While the scaling up and M&E activities are on-going, the project has since broadened from a sweetpotato-pig system perspective to a pig-cropfeed system perspective based on farmers needs. It has included other crop feeds such as cassava and peanut stems in the research portfolio. New technologies based on on-going PTD will continuously be incorporated into the future training curriculum.Dai Peters is currently a senior scientist with the International Center for Tropical Agriculture (CIAT) based in Hanoi, Vietnam. This publication is based on research conducted while she was a research scientist with the International Potato Center (CIP). She holds a PhD from North Carolina State University. Her research interests include on-farm participatory research methodologies, agroenterprise development, and sweetpotato-pig farming systems in Vietnam and Papua, Indonesia. Her recent publications include a manual on crop-based pig feed systems, post-harvest fermentation of sweetpotato roots and vines, and agroenterprise development.Nguyen Thi Tinh is currently a coordinator of the sweetpotato-pig improvement project at the International Potato Center in Vietnam. Ms. Tinh holds a Masters degree in animal nutrition from Wageningen University, Netherlands. She participated in the project on pig feeding trials for five years.Mai Thach Hoanh is a sweetpotato breeder with the Root Crop Research Center of Vietnam Agricultural Science Institute (VASI). He holds a PhD in sweetpotato breeding from the same institute. He participated in the project for seven years on sweetpotato selection. Nguyen The Yen is a crop scientist in the Food Crop Research Institute of Vietnam. He holds a PhD in sweetpotato breeding from VASI. He participated in the project for five years on sweetpotato selection.Pham Ngoc Thach is a lecturer with the Hanoi Agricultural University. He holds a PhD in veterinarian science from the same university. He participated in the project for five years in controlling pig diseases during the feeding trials.Keith Fuglie is a regional coordinator and research scientist in the International Potato Center based at Bogor, Indonesia. He holds a PhD in agriculture economics from the University of Wisconsin. He designed the impact study for the project.     

Effect of foliar application of oligochitosan with different molecular weight on growth promotion and fruit yield enhancement of chili plant

Oligochitosan (OC) is effective biostimulant on growth promotion and elicitation against disease infection for plants. However, the range of OC molecular weight that exhibits the most effective activity is not fully understood and requires further investigation. In this study, OCs with different weight average molecular weight (Mw) were prepared by gamma Co-60 irradiation degradation of chitosan in solution and the effect on growth promotion and enhancement of fruit yield of chili plant (Capsicum frutescens L.) by foliar application of OCs particularly with Mw of 7.8, 5.0, and 2.5 kDa was investigated. Chili plants, cultivated in a greenhouse were sprayed with OC concentration of 50 mg/L for three times. Results indicated that among treatments, OC with 2.5 kDa proved to be the best, which increased the shoot fresh weight by 71.5%, shoot dry weight by 184%, total chlorophyll content by 12%, and fruit fresh weight by 49.8% for the control. Thus, OC with low Mw (2.5 kDa) that can be suitably produced on large scale by gamma Co-60 ray irradiation degradation of chitosan solution is potentially promising to apply as a biostimulant to enhance chili fruit yield significantly.     

Shotgun and TMT-Labeled Proteomic Analysis of the Ovarian Proteins of an Insect Vector,Aedes aegypti (Diptera: Culicidae)

Aedes aegypti [Linnaeus in Hasselquist; yellow fever mosquito] transmits several viruses that infect millions of people each year, including Zika, dengue, yellow fever, chikungunya, and West Nile. Pathogen transmission occurs during blood feeding. Only the females blood feed as they require a bloodmeal for oogenesis; in the bloodmeal, holo-transferrin and hemoglobin provide the females with a high iron load. We are interested in the effects of the bloodmeal on the expression of iron-associated proteins in oogenesis. Previous data showed that following digestion of a bloodmeal, ovarian iron concentrations doubles by 72 hr. We have used shotgun proteomics to identify proteins expressed in Ae. aegypti ovaries at two oogenesis developmental stages following blood feeding, and tandem mass tag-labeling proteomics to quantify proteins expressed at one stage following feeding of a controlled iron diet. Our findings provide the first report of mosquito ovarian protein expression in early and late oogenesis. We identify proteins differentially expressed in the two oogenesis development stages. We establish that metal-associated proteins play an important role in Ae. aegypti oogenesis and we identify new candidate proteins that might be involved in mosquito iron metabolism. Finally, this work identified a unique second ferritin light chain subunit, the first reported in any species. The shotgun proteomic data are available via ProteomeXchange with identifier PXD005893, while the tandem mass tag-labeled proteomic data are available with identifier PXD028242.     

Assessment of biochemical and antioxidant diversities in a shallot germplasm collection from Vietnam and its surrounding countries

The shallot is considered an important genetic resource for Allium breeding programs because, compared to the bulb onion, the shallot contains higher levels of several functional chemical compounds. However, there may be differences in content, composition and beneficial activity among shallot landraces. This study was carried out to characterize the differences in phenolic, quercetin, sugar, S-alk(en)yl-l-cystein sulfoxide (ACSO), and saponin contents and antioxidant capacities of a shallot germplasm including 31 strains derived from different regions of Vietnam and six other countries. A wide variation was observed in the quantitative analyses of the chemical contents. Shallots with high contents of polyphenols, saponins, and quercetins were found in the south of Vietnam and other low-latitude countries. Meanwhile, those possessing fairly high ACSO and sugar contents were observed in the north of Vietnam. Qualitative analysis of saponins via thin layer chromatography did not show clear variation among shallot strains, but polymorphism was observed between the shallot and other Allium species, such as A. roylei. The principal component analysis could clearly discriminate shallot strains by their geographical origins. All shallot strains showed potent antioxidant activities in a DPPH assay. The highest antioxidant capacity was in the strains possessing relatively high contents of polyphenol, quercetin, and saponin. Significant correlations were found between antioxidant capacity (IC ₅₀ ^?1 ) and four groups of chemical compounds (polyphenols, quercetins, saponins, and ACSOs) (r = 0.40–0.59). A strong correlation was observed between IC ₅₀ ^?1 and quercetin contents (r = 0.59, p < 0.01). The six Fusarium-inoculated shallot strains seemed to be adequately resistant against disease, and the levels of resistance may be related to the saponin content in the bulb tissues.     

越南马铃薯晚疫病的研究概况

晚疫病是越南马铃薯上最重要的病害。各马铃薯产区均有发生。在江河三角洲地区晚疫病的发生通常比较晚，从12月下旬即第二个生长季后半期开始发病，在1月至2月气温较低、湿度较大时，晚疫病常常严重流行。在Sapa地区（北京高原），整个生长晚疫病对马铃薯作物都是主要威胁。在感病品种上病害的发生和严重度可达到100％。在大叨地区，在干旱季节（11－4月）晚疫病发生最轻，而在雨季（5－10月）严重流行。在越南，还未进行晚疫病菌生物学和流行学方面的基础研究。对晚疫病防治研究主要集中在筛选新的杀菌剂。大部分工作集中在抗病育种和抗病品种的筛选。目前需要进行晚疫综合治疗、流行学、晚疫病菌生物学和抗病育方面的深入研究和培训。     

Zoonotic origin and transmission of Middle East respiratory syndrome coronavirus in the UAE

Since the emergence of Middle East respiratory syndrome coronavirus (MERS‐CoV) in 2012, there have been a number of clusters of human‐to‐human transmission. These cases of human‐to‐human transmission involve close contact and have occurred primarily in healthcare settings, and they are suspected to result from repeated zoonotic introductions. In this study, we sequenced whole MERS‐CoV genomes directly from respiratory samples collected from 23 confirmed MERS cases in the United Arab Emirates (UAE). These samples included cases from three nosocomial and three household clusters. The sequences were analysed for changes and relatedness with regard to the collected epidemiological data and other available MERS‐CoV genomic data. Sequence analysis supports the epidemiological data within the clusters, and further, suggests that these clusters emerged independently. To understand how and when these clusters emerged, respiratory samples were taken from dromedary camels, a known host of MERS‐CoV, in the same geographic regions as the human clusters. Middle East respiratory syndrome coronavirus genomes from six virus‐positive animals were sequenced, and these genomes were nearly identical to those found in human patients from corresponding regions. These data demonstrate a genetic link for each of these clusters to a camel and support the hypothesis that human MERS‐CoV diversity results from multiple zoonotic introductions.     

A study of genetic diversity of sesame (<Emphasis Type="Italic">Sesamum indicum</Emphasis> L.) in Vietnam and Cambodia estimated by RAPD markers

Sesame (Sesamum indicum L.) is a traditional oil crop cultivated throughout South East Asia. To estimate the genetic diversity of this crop in parts at the region, 22 sesame accessions collected in Vietnam and Cambodia were analyzed using 10 RAPD markers. The 10 primers generated 107 amplification products of which 88 were polymorphic fragments (83%). Genetic diversity of all populations was H_t = 0.34 when estimated by Nei’s genetic diversity and species diversity was H′_sp = 0.513 when estimated by Shannon diversity index. Genetic distance ranged from 0.03 to 0.43, with a mean genetic distance of 0.23. The unweighted pair group method with arithmetic averages (UPGMA) cluster analysis for the 22 accessions divided the material in four groups. The dendrogram revealed a clear division among the sesame accessions based on their geographical region. Interestingly, some geographically distant accessions clustered in the same group, which might indicate the human factor involved in the spreading of sesame varieties. The high level of polymorphism shown suggests that RAPD techniques can also be useful for the selection of parents in sesame (Sesamum indicum L.) breeding program and for cultivar differentiation.     

An assessment of genetic diversity and population structures of fifteen Vietnamese indigenous pig breeds for supporting the decision making on conservation strategies

Tropical Animal Health and Production - The study aimed to characterize genetic diversity, genetic clusters, and phylogenetic relationships of 15 Vietnamese indigenous pig breeds across the country...