Genetic structure and diversity within and among six populations of Capparis decidua (forssk.) edgew. from Saudi Arabia

Capparis decidua is a rangeland plant species growing in isolated populations in Saudi Arabia. Genetic diversity within and among six populations (Madina, Farasan island, Hawayer Assos, Khor Assos, Raudhat Khuraim, and Taif) of C. decidua was studied using RAPD technique. Of the 25 random primers were used, eighteen (18) primers generated discernible and reproducible bands. A total of 152 reproducible RAPD bands across the 36 individuals were amplified. Out of those, 117 (76.2%) RAPD bands were polymorphic. The number of polymorphic bands per primer ranged between 3 and 11 with an average of 6.5 bands per primer. Populations differed in the level of genetic diversity as shown from the percentage of polymorphic bands. Farasan population had the highest level of genetic diversity (24.3%) and two populations Khor Assos (5.9%) and Taif (4.6%) had the lowest genetic diversity. Analysis of molecular variance (AMOVA) showed highly significant differences among populations. Among the population variance accounted, there is a higher percentage of the total variance (average 77.67%, SD±8.21) than within populations (average 22.33%, SD±8.21). There is no significant correlation between geographical distance and genetic distance was found. However, there was a significant positive correlation between molecular genetic variation and actual population size. The implication of the results of this study in devising strategy for conservation of C. decidua is discussed.Key words: Capparis decidua, Tandhab, Assos, Population size, RAPD markers, Genetic diversity

Comparative analysis of diversity based on morphoagronomic traits and molecular markers in durum wheat under heat stress

The objectives of this study were to compare the application and utility of sequence-related amplified polymorphism (SRAP) and target region amplification polymorphism (TRAP) techniques for the analysis of genetic diversity among durum wheat genotypes under heat stress and to compare genetic diversity estimated using molecular markers with morpho-agronomic performance under heat stress. Six durum wheat genotypes were used in this study. They were evaluated phenotypically for heat tolerance. The dendrogram generated from standardized morpho-agronomic data separated the six durum wheat genotypes into three main groups. The dendrogram generated from the standardized morpho-agronomic data separated the six durum wheat genotypes into three clusters, which diverged at similarity index of 0.72. The dendrogram based on SRAP markers differed from that based on TRAP markers. The combined dendrogram (SRAP, TRAP and morpho-agronomic data) agrees better with the grouping of these durum wheat genotypes depending on pedigree and the dendrogram generated by morpho-agronomic data alone.Key words: Durum wheat, genetic diversity, heat tolerance, morpho-agronomic, sequence-related amplified polymorphism (SRAP) markers, target region amplification polymorphism (TRAP) markers

Using molecular techniques for rapid detection of Salmonella serovars in frozen chicken and chicken products collected from Riyadh, Saudi Arabia

The current study was aimed to investigate the incidence of different Salmonella serovars in chicken products either from local or imported source. A total of 152 samples of chicken and chicken productswere collected from different retail establishment markets in Riyadh, KSA including 38 local whole frozen chickens, 62 imported whole frozen chickens, 22 whole poultry eggs and 30 local chicken cuts samples and examined by standard microbiological techniques (SMT). Salmonella isolation revealed a total percentage of 5.92%; chicken cuts revealed a high incidence among the examined samples (10%), followed by local frozen chickens and imported frozen chicken samples with incidence of 7.89 and 4.83%, respectively. For this experiment, the whole chicken eggs were negative for Salmonella species by SMT. Salmonella enteritidis was dominating among the recovered Salmonella serovars, followed bySalmonella typhimurium, while only two strains of Salmonella agona and Salmonella newport were isolated. The PCR assay combined with Rappaport- Vassiliadis (RV) selective broth (PCR-RV) for the detection of Salmonella species in the collected field samples revealed the same positive samples directly from the imported frozen chickens and whole chicken eggs which gave negative results by SMT. Thus PCR-RV technique is rapid, time saving and applicable to detect Salmonella serovarsdirectly from chicken samples

Multiplex polymerase chain reaction for detection and characterization of shiga toxigenic Escherichia coli (STEC)

Escherichia coli is ubiquitous in the cow's environment that is contaminated by feces, and it is also a frequent cause of bovine mastitis. Thus, the present study was targeted at the rapid detection and characterization of shiga toxigenic E. coli (STEC) in bovine fecal and milk samples. Twenty two strains of E. coli (39.29%) were isolated from 56 diarrheic calves, while only 5 strains (20.83%) were isolated from apparently normal contact calves. Moreover, 20 strains of E. coli (25%) were isolated from milk samples collected from 80 animals suffering from mastitis and subclinical mastitis. E. coli serovars yielded from bacteriological examination of milk samples were similar to that of fecal samples. Serogroup-specific multiplex polymerase chain reaction (PCR) assay could detect all the bacteriologically positive samples as well as 4 strains (7.98%), O157:H7 and 3 strains (5.36%), O111 from diarrheic calves and 2 strains (8.33%), O111 from normal calves. Such samples were proved to be negative by bacteriological examination. Multiplex PCR for detection of genes encoding accessorySTEC virulence factors, such as shiga toxin type-2 (stx2) and intimin gene (eaeA) revealed the specificity of such gene to O157:H7 serovars and small number of other sero-groups

Integrating genetic and gene expression data: application to cardiovascular and metabolic traits in mice

The millions of common DNA variations that occur in the human population, or among inbred strains of mice and rats, perturb the expression (transcript levels) of a large fraction of the genes expressed in a particular tissue. The hundreds or thousands of common cis-acting variations that occur in the population may in turn affect the expression of thousands of other genes by affecting transcription factors, signaling molecules, RNA processing, and other processes that act in trans. The levels of transcripts are conveniently quantitated using expression arrays, and the cis- and trans-acting loci can be mapped using quantitative trait locus (QTL) analysis, in the same manner as loci for physiologic or clinical traits. Thousands of such expression QTL (eQTL) have been mapped in various crosses in mice, as well as other experimental organisms, and less detailed maps have been produced in studies of cells from human pedigrees. Such an integrative genetics approach (sometimes referred to as “genetical genomics”) is proving useful for identifying genes and pathways that contribute to complex clinical traits. The coincidence of clinical trait QTL and eQTL can help in the prioritization of positional candidate genes. More importantly, mathematical modeling of correlations between levels of transcripts and clinical traits in genetic crosses can allow prediction of causal interactions and the identification of “key driver” genes. An important objective of such studies will be to model biological networks in physiologic processes. When combined with high-density single nucleotide polymorphism (SNP) mapping, it should be feasible to identify genes that contribute to transcript levels using association analysis in outbred populations. In this review we discuss the basic concepts and applications of this integrative genomic approach to cardiovascular and metabolic diseases

Conceptualizing pathways linking women's empowerment and prematurity in developing countries.

BackgroundGlobally, prematurity is the leading cause of death in children under the age of 5. Many efforts have focused on clinical approaches to improve the survival of premature babies. There is a need, however, to explore psychosocial, sociocultural, economic, and other factors as potential mechanisms to reduce the burden of prematurity. Women's empowerment may be a catalyst for moving the needle in this direction. The goal of this paper is to examine links between women's empowerment and prematurity in developing settings. We propose a conceptual model that shows pathways by which women's empowerment can affect prematurity and review and summarize the literature supporting the relationships we posit. We also suggest future directions for research on women's empowerment and prematurity.MethodsThe key words we used for empowerment in the search were "empowerment," "women's status," "autonomy," and "decision-making," and for prematurity we used "preterm," "premature," and "prematurity." We did not use date, language, and regional restrictions. The search was done in PubMed, Population Information Online (POPLINE), and Web of Science. We selected intervening factors-factors that could potentially mediate the relationship between empowerment and prematurity-based on reviews of the risk factors and interventions to address prematurity and the determinants of those factors.ResultsThere is limited evidence supporting a direct link between women's empowerment and prematurity. However, there is evidence linking several dimensions of empowerment to factors known to be associated with prematurity and outcomes for premature babies. Our review of the literature shows that women's empowerment may reduce prematurity by (1) preventing early marriage and promoting family planning, which will delay age at first pregnancy and increase interpregnancy intervals; (2) improving women's nutritional status; (3) reducing domestic violence and other stressors to improve psychological health; and (4) improving access to and receipt of recommended health services during pregnancy and delivery to help prevent prematurity and improve survival of premature babies.ConclusionsWomen's empowerment is an important distal factor that affects prematurity through several intervening factors. Improving women's empowerment will help prevent prematurity and improve survival of preterm babies. Research to empirically show the links between women's empowerment and prematurity is however needed