Gonads annual development of Kelee shad, <Emphasis Type="Italic">Hilsa kelee</Emphasis> (Cuvier, 1829) from the coastal waters of Pakistan and its spawning ecology

Annual reproductive cycle and spawning ecology of Kelee shad, Hilsa kelee were studied. The sex ratios did not exhibit as 1: 1; whereas 69.19% were females. On the basis of histological examination, the maturity of female gonads of H. kelee was categorized in eight developmental stages: immature, developing, fully developed, hydrated, running ripe, partially spent, spent and post spawning. Whereas males of this species were categorized in five developmental stages: immature, developing, ripe, partially spent and spent. This fish is repeatedly spawner and spawns twice per year: in April to June and August to October. The values of exponent b in the length weight regressions (W = al ^b ) slightly varied in males b = 3.133, R ² = 0.96 and P < 0.01 and females b = 3.143, R ² = 0.95 and P < 0.001. The linear regressions of length-weight relationships were significant for both males and females.     

Active Rho kinase (ROK-alpha ) associates with insulin receptor substrate-1 and inhibits insulin signaling in vascular smooth muscle cells.

Recent studies from our laboratory have shown that insulin stimulates myosin-bound phosphatase (MBP) in vascular smooth muscle cells (VSMCs) by decreasing site-specific phosphorylation of the myosin-bound subunit (MBS) of MBP via nitric oxide/cGMP-mediated Rho/Rho kinase inactivation. Here we tested potential interactions between Rho kinase and insulin signaling pathways. In control VSMCs, insulin inactivates ROK-alpha, the major Rho kinase isoform in VSMCs, and inhibits thrombin-induced increase in ROK-alpha association with the insulin receptor substrate-1 (IRS-1). Hypertension (in spontaneous hypertensive rats) or expression of an active RhoA(V14) up-regulates Rho kinase activity and increases ROK-alpha/IRS-1 association resulting in IRS-1 serine phosphorylation that leads to inhibition of both insulin-induced IRS-1 tyrosine phosphorylation and phosphatidylinositol 3-kinase (PI3-kinase) activation. In contrast, expression of dominant negative RhoA or cGMP-dependent protein kinase type I alpha inactivates Rho kinase, abolishes ROK-alpha/IRS-1 association, and potentiates insulin-induced tyrosine phosphorylation and PI3-kinase activation leading to decreased MBS(T695) phosphorylation and decreased MBP inhibition. Collectively, these results suggest a novel function for ROK-alpha in insulin signal transduction at the level of IRS-1 and potential cross-talk between cGMP-dependent protein kinase type I alpha, Rho/Rho kinase signaling, and insulin signaling at the level of IRS-1/PI3-kinase.     

High prevalence of mouse mammary tumor virus-like gene sequences in breast cancer samples of Iranian women

Mouse mammary tumor virus (MMTV) is considered to be responsible for breast tumor development in mice. In several instances sequences homologous to the genome of this virus have been reported in human breast cancer samples.

Here we aimed to evaluate MMTV involvement in human breast cancer development. DNA was extracted from 118 formalin fixed and paraffin embedded malignant (n = 59) and benign (n = 59) breast lesions. Using two sets of outer and inner MMTV-like envelope specific primers, in a nested PCR setup, MMTV genome was detected in 19 samples out of 59 (%32.2) cases of breast carcinomas, while in non-malignant breast tissue samples, only 3 samples out of 59 (%5) were positive. The difference was statistically highly significant (p < 0.001). Alignment of PCR amplified sequences with BR6, GR and C3H mouse mammary tumor virus strains emerged to be around 99% identical which is indicative of tumor tissue infection by an exogenous mouse MMTV genome.     

Y-chromosome lineages trace diffusion of people and languages in southwestern Asia

The origins and dispersal of farming and pastoral nomadism in southwestern Asia are complex, and there is controversy about whether they were associated with cultural transmission or demic diffusion. In addition, the spread of these technological innovations has been associated with the dispersal of Dravidian and Indo-Iranian languages in southwestern Asia. Here we present genetic evidence for the occurrence of two major population movements, supporting a model of demic diffusion of early farmers from southwestern Iran-and of pastoral nomads from western and central Asia-into India, associated with Dravidian and Indo-European-language dispersals, respectively.     

A method for the assessment of disease associations with single-nucleotide polymorphism haplotypes and environmental variables in case-control studies

The rough draft of the human genome map has been used to identify most of the functional genes in the human genome, as well as to identify nucleotide variations, known as "single-nucleotide polymorphisms" (SNPs), in these genes. By use of advanced biotechnologies, researchers are beginning to genotype thousands of SNPs from biological samples. Among the many possible applications, one of them is the study of SNP associations with complex human diseases, such as cancers or coronary heart diseases, by using a case-control study design. Through the gathering of environmental risk factors and other lifestyle factors, such a study can be effectively used to investigate interactions between genes and environmental factors in their associations with disease phenotype. Earlier, we developed a method to statistically construct individuals' haplotypes and to estimate the distribution of haplotypes of multiple SNPs in a defined population, by use of estimating-equation techniques. Extending this idea, we describe here an analytic method for assessing the association between the constructed haplotypes along with environmental factors and the disease phenotype. This method is also robust to the model assumptions and is scalable to a large number of SNPs. Asymptotic properties of estimations in the method are proved theoretically and are tested for finite sample sizes by use of simulations. To demonstrate the use of the method, we applied it to assess the possible association between apolipoprotein CIII (six coding SNPs) and restenosis by using a case-control data set. Our analysis revealed two haplotypes that may reduce the risk of restenosis.     

A growth kinetic model of<Emphasis Type="Italic"> Kluyveromyces marxianus</Emphasis> cultures on cheese whey as substrate

This work presents a multi-route, non-structured kinetic model for determination of microbial growth and substrate consumption in an experimental batch bioreactor in which -galactosidase is produced by Kluyveromyces marxianus growing on cheese whey. The main metabolic routes for lactose, and oxygen consumption, cell growth, and ethanol production are derived based on experimental data. When these individual rates are combined into a single growth rate, by rewriting the model equations, the model re-interpretation has a complexity similar to that of the usual variations of the Monod kinetic model, available in the literature. Furthermore, the proposed model is in good agreement with the experimental data for different growth temperatures, being acceptable for dynamic simulations, processes optimization, and implementations of model-based control technologies.     

Evidence for a functional interaction between the ClC-2 chloride channel and the retrograde motor dynein complex

The ClC-2 chloride channel has been implicated in essential physiological functions. Analyses of ClC-2 knock-out mice suggest that ClC-2 expression in retinal pigment epithelia and Sertoli cells normally supports the viability of photoreceptor cells and male germ cells, respectively. Further, other studies suggest that ClC-2 expression in neurons may modify inhibitory synaptic transmission via the gamma-aminobutyric acid, type A receptor. However, complete understanding of the physiological functions of ClC-2 requires elucidation of the molecular basis for its regulation. Using cell imaging and biochemical and electrophysiological techniques, we show that expression of ClC-2 at the cell surface may be regulated via an interaction with the dynein motor complex. Mass spectrometry and Western blot analysis of eluate from a ClC-2 affinity matrix showed that heavy and intermediate chains of dynein bind ClC-2 in vitro. The dynein intermediate chain co-immunoprecipitates with ClC-2 from hippocampal membranes suggesting that they also interact in vivo. Disruption of dynein motor function perturbs ClC-2 localization and increases the functional expression of ClC-2 in the plasma membranes of COS7 cells. Thus, cell surface expression of ClC-2 may be regulated by dynein motor activity. This work is the first to demonstrate an in vivo interaction between an ion channel and the dynein motor complex.     

Decreased insulin action in skeletal muscle from patients with McArdle's disease

Insulin action is decreased by high muscle glycogen concentrations in skeletal muscle. Patients with McArdle's disease have chronic high muscle glycogen levels and might therefore be at risk of developing insulin resistance. In this study, six patients with McArdle's disease and six matched control subjects were subjected to an oral glucose tolerance test and a euglycemic-hyperinsulinemic clamp. The muscle glycogen concentration was 103 +/- 45% higher in McArdle patients than in controls. Four of six McArdle patients, but none of the controls, had impaired glucose tolerance. The insulin-stimulated glucose utilization and the insulin-stimulated increase in glycogen synthase activity during the clamp were significantly lower in the patients than in controls (51.3 +/- 6.0 vs. 72.6 +/- 13.1 micromol x min(-1) x kg lean body mass(-1), P < 0.05, and 53 +/- 15 vs. 79 +/- 9%, P < 0.05, n = 6, respectively). The difference in insulin-stimulated glycogen synthase activity between the pairs was significantly correlated (r = 0.96, P < 0.002) with the difference in muscle glycogen level. The insulin-stimulated increase in Akt phosphorylation was smaller in the McArdle patients than in controls (45 +/- 13 vs. 76 +/- 13%, P < 0.05, respectively), whereas basal and insulin-stimulated glycogen synthase kinase 3alpha and protein phosphatase-1 activities were similar in the two groups. Furthermore, the ability of insulin to decrease and increase fat and carbohydrate oxidation, respectively, was blunted in the patients. In conclusion, these data show that patients with McArdle's glycogen storage disease are insulin resistant in terms of glucose uptake, glycogen synthase activation, and alterations in fuel oxidation. The data further suggest that skeletal muscle glycogen levels play an important role in the regulation of insulin-stimulated glycogen synthase activity.