Telomeric association: another characteristic of cancer chromosomes?

Telomeric associations between single chromatids and double chromatids of nonhomologous normal human chromosomes and altered markers were observed in two morphologically distinct squamous-cell carcinoma lines derived from a surgical specimen. Chromosomes 2, 3, 5, and 16 were associated by their telomeric ends more frequently than other chromosomes.     

Introgression of Recombinant 1RSWR.1BL Translocation and Rust Resistance Genes in Bread Wheat cv. HD2967 Through Marker-Assisted Selection

Bread wheat (Triticum aestivum L.) is one of the major cereal crops utilized worldwide for bread making. The presence of secalin locus on 1RS leads to the sticky dough and poor bread-making quality of wheat. In the present study, two donor parents, one with distal rye chromatin (1RS44:38) and another with distal wheat chromatin (Pavon MA1) without secalin, and one recipient elite wheat cultivar HD2967 were used. In 1RS44:38, the distal rye region has the Pm8 gene to which the QTL for superior root traits is linked, while in Pavon MA1 with Glu-B3/Gli-B1, the Pm8 gene was found to be absent. This distal rye region having root trait QTL was introgressed into the HD2967 derivatives using marker-assisted backcross selection. The derivatives with distal rye region introgression had higher root biomass, drought resistance, and 6–8% higher yield than the recipient parent cultivar. HD2967 is highly susceptible to yellow rust. Therefore, in the second backcross, the rust-resistant version of HD2967 (Lr57?+?Yr40) was used to introgress rust resistance in the derivatives. Background selection was done using polymorphic wheat anchored SSR markers of A, B, and D genomes of wheat which led to the selection of derivatives with?> 90% background of the recipient cultivar. The significant findings in this study include higher root biomass, improved yield, rust resistance in the derivatives, and retaining the alleles of Glu-B3/Gli-B1 along with Pm8 and the absence of secalin.

     

HIV risk among MSM in Senegal: a qualitative rapid assessment of the impact of enforcing laws that criminalize same sex practices

Men who have sex with men (MSM) are at high risk for HIV in Senegal, with a prevalence of 21.5%. In December 2008, nine male HIV prevention workers were imprisoned for "acts against nature" prohibited by Senegalese law. This qualitative study assessed the impact of these arrests on HIV prevention efforts. A purposive sample of MSM in six regions of Senegal was recruited by network referral. 26 in-depth interviews (IDIs) and 6 focus group discussions (FGDs) were conducted in July-August 2009. 14 key informants were also interviewed. All participants reported pervasive fear and hiding among MSM as a result of the December 2008 arrests and publicity. Service providers suspended HIV prevention work with MSM out of fear for their own safety. Those who continued to provide services noticed a sharp decline in MSM participation. An effective response to the HIV epidemic in Senegal should include active work to decrease enforcement of this law.     

Systems biological approach to investigate the lack of familial link between Down's Syndrome & Neural Tube Disorders

Systems Biology involves the study of the interactions of biological systems and ultimately their functions. Down''s syndrome (DS) is one of the most common genetic disorders which are caused by complete, or occasionally partial, triplication of chromosome 21, characterized by cognitive and language dysfunction coupled with sensory and neuromotor deficits. Neural Tube Disorders (NTDs) are a group of congenital malformations of the central nervous system and neighboring structures related to defective neural tube closure during the first trimester of pregnancy usually occurring between days 18-29 of gestation. Several studies in the past have provided considerable evidence that abnormal folate and methyl metabolism are associated with onset of DS & NTDs. There is a possible common etiological pathway for both NTDs and Down''s syndrome. But, various research studies over the years have indicated very little evidence for familial link between the two disorders. Our research aimed at the gene expression profiling of microarray datasets pertaining to the two disorders to identify genes whose expression levels are significantly altered in these conditions. The genes which were 1.5 fold unregulated and having a p-value <0.05 were filtered out and gene interaction network were constructed for both NTDs and DS. The top ranked dense clique for both the disorders were recognized and over representation analysis was carried out for each of the constituent genes. The comprehensive manual analysis of these genes yields a hypothetical understanding of the lack of familial link between DS and NTDs. There were no genes involved with folic acid present in the dense cliques. Only – CBL, EGFR genes were commonly present, which makes the allelic variants of these genes – good candidates for future studies regarding the familial link between DS and NTDs.

Abbreviations

NTD - Neural Tube Disorders, DS - Down''s Syndrome, MTHFR - Methylenetetrahydrofolate reductase, MTRR– 5 - methyltetrahydrofolate-homocysteine methyltransferase reductase.     

Transfer of grain softness from 5U-5A wheat-Aegilops triuncialis substitution line to bread wheat through induced homeologous pairing

Journal of Plant Biochemistry and Biotechnology - Bread wheat sustains genes for grain softness on “Ha” locus of short arm of 5D chromosome. Pina-D1 and Pinb-D1 alleles of...     

Bioinsecticidal activity of Murraya koenigii miraculin-like protein against Helicoverpa armigera and Spodoptera litura

Miraculin-like proteins, belonging to the Kunitz superfamily, are natural plant defense agents against pests and predators, and therefore are potential biopesticides for incorporation into pest-resistant crops. Here, a miraculin-like protein from Murraya koenigii was assessed for its in vitro and in vivo effects against two polyphagous lepidopteran insect pests, Helicoverpa armigera and Spodoptera litura. M. koenigii miraculin-like protein (MKMLP) inhibited the trypsin-like activity and total protease activity of H. armigera gut proteinases (HGP) by 78.5 and 40%, respectively, and S.litura gut proteinases (SGP) by 81 and 48%, respectively. The inhibitor was stable and actively inhibited the proteolysis of both HGP and SGP enzymes for up to 72 h. Incorporation of MKMLP into artificial diet adversely affected the growth and development of pests in a dose-dependent manner. After 10 days of feeding on diets containing 200 μM MKMLP, larval weight was reduced to 69 and 44.8% and larval mortality was increased to 40 and 43.3% for H. armigera and S litura, respectively. The LC(50) of MKMLP was 0.34 and 0.22% of the diet for H.armigera and S. litura, respectively. These results demonstrate the efficacy of MKMLP as a potential plant defense agent against H. armigera and S. litura.     

Antifertility effect of Melia azedarach Linn. (dharek) seed extract in female albino rats

In the present study, the effect of oral administration of Melia azedarach Linn. (dharek) seed extract on fertility index, uterine weight and various histological and biochemical parameters of uterus were studied in the adult cyclic Wistar rats. Average number of embryos and implantation losses in the pregnant animals treated with dharek seed extract was also studied. The extract was prepared using a flash evaporator at 35 degrees C and dissolved in olive oil to prepare doses on per kg body weight basis. The results indicated a reduction in fertility index and average number of embryos in mated rats treated with the dharek extract. Pre-implantation, post-implantation and total prenatal mortalities were increased in rats treated with dharek seed extract during early (D1-D7) and late (D7-D18) stages of gestation period at doses of 5, 10 and 20 mg kg(-1) body wt day(-1). Histological studies showed a significant reduction in myometrial thickness, uterine gland diameter, luminal diameter of uterine glands and luminal epithelial cell height in rats treated with dharek seed extract at 1mg kg(-1) body wt day(-1) for 18 days. Pits and folds in luminal epithelial, mitotic activity in luminal and glandular epithelial cells of uterus were observed to be absent. Biochemically, a significant increase in protein and glycogen contents was observed. Thus, in conclusion, the application of this plant extract in rodent control programme may help to elevate the socioeconomic status of the society.     

Rho kinase and Ca2+ entry mediate increased pulmonary and systemic vascular resistance in L-NAME-treated rats

The small GTP-binding protein and its downstream effector Rho kinase play an important role in the regulation of vasoconstrictor tone. Rho kinase activation maintains increased pulmonary vascular tone and mediates the vasoconstrictor response to nitric oxide (NO) synthesis inhibition in chronically hypoxic rats and in the ovine fetal lung. However, the role of Rho kinase in mediating pulmonary vasoconstriction after NO synthesis inhibition has not been examined in the intact rat. To address this question, cardiovascular responses to the Rho kinase inhibitor fasudil were studied at baseline and after administration of an NO synthesis inhibitor. In the intact rat, intravenous injections of fasudil cause dose-dependent decreases in systemic arterial pressure, small decreases in pulmonary arterial pressure, and increases in cardiac output. L-NAME caused a significant increase in pulmonary and systemic arterial pressures and a decrease in cardiac output. The intravenous injections of fasudil after L-NAME caused dose-dependent decreases in pulmonary and systemic arterial pressure and increases in cardiac output, and the percent decreases in pulmonary arterial pressure in response to the lower doses of fasudil were greater than decreases in systemic arterial pressure. The Ca(++) entry blocker isradipine also decreased pulmonary and systemic arterial pressure in L-NAME-treated rats. Infusion of sodium nitroprusside restored pulmonary arterial pressure to baseline values after administration of L-NAME. These data provide evidence in support of the hypothesis that increases in pulmonary and systemic vascular resistance following L-NAME treatment are mediated by Rho kinase and Ca(++) entry through L-type channels, and that responses to L-NAME can be reversed by an NO donor.