Ultrastructural morphology of ectoplacental cone trophoblasts of hamster embryos.

The invasiveness of trophoblast cells is well known, but it is not clear whether they achieve this property by being transformed to other cell types (like malignant ones) or remain benign. Trophoblasts, in culture, were studied ultrastructurally by examining the surface morphology of the cell vis-à-vis their cytoplasmic outgrowth, and the presence and/or absence of ruffling membranes, filopodia, microvilli, pinocytotic pits or bleb-like structures was observed. Results revealed formation of ruffling membranes only on the leading edge, a presence of slender filopodia and pinocytotic pits but an absence of microvilli and bleb-like structures, the characteristic features of a transformed cell. The study indicated that the trophoblast cells, in spite of being invasive, do not convert to any other cell type.     

Polymorphisms in the pituitary growth hormone gene and its receptor associated with coronary artery disease in a predisposed cohort from India

We investigated the promoter polymorphisms of the pituitary growth hormone gene (GH1) and exon 3 deletion polymorphism (GHRd3) in its receptor gene (GHR) in 299 angiographically proven patients with coronary artery disease (CAD) and 231 asymptomatic controls enrolled in the ongoing Indian Atherosclerosis Research Study. Real time PCR based analysis of the GHR variant showed significant association of the GHRd3 deletion allele with CAD (OR 0.48, 95% CI: 0.30–0.76, P = 0.0014) and a dominant model of inheritance (Akaike information criterion = 482). The deletion allele showed significant association with high plasma HDL-c levels (P = 0.001). Sequencing of the proximal promoter region of GH1 revealed 12 novel polymorphisms and a TAGA haplotype constituted by the functional SNPs rs2005171, rs11568828, rs2005172 and rs6171, that showed significant association with CAD alone (adjusted OR of 3.31 (95% CI = 1.33–8.29, P = 0.011) and in CAD patients with diabetes (P = 0.019). Mean standardized height was associated with three of the four haplotype-tagging SNPs in the cohort (P ≤ 0.03). Eleven of the 12 polymorphic promoter SNPs contributed to 14.7% of variation in height in females in the whole dataset (P = 0.029). CAD patients with history of stroke exhibited marginally significantly lower mean height as compared to rest of the cohort (P < 0.006). In conclusion, genetic polymorphisms in the GHR gene and its ligand, GH1, may modulate the risk of CAD in the Asian Indian population.     

Genotype-phenotype relationship of <Emphasis Type="Italic">F7</Emphasis> R353Q polymorphism and plasma factor VII coagulant activity in Asian Indian families predisposed to coronary artery disease

Elevated factor VII (FVII) level is a risk factor for coronary artery disease (CAD). We investigated the role of R353Q polymorphism in the F7 gene in 139 Indian families with CAD, comprising of 222 affected subjects, 105 unaffected subjects and 126 affected sibling pairs. Plasma per cent FVIIc activity (FVII.c activity) differed significantly across R353Q genotype (P < 0.0001). Frequency of subjects with RR and QQ genotypes were higher in 4th quartile and 1st quartile of FVII.c activity, respectively (P < 0.0001). F7 R353Q SNP was able to explain up to 7% of variation in FVII.c activity by regression analysis and an additive genetic component of variance of 28.04% by heritability analysis. Quantitative trait loci analysis showed suggestive linkage evidence of F7 SNP with per cent FVII.c activity (LOD score −1.82; P = 0.002). Individuals with RR and RQ genotypes carried an OR of 2.071 (95% c.i. = 1.506−2.850) and 2.472 (95% c.i. = 1.679−3.641), respectively, towards CAD risk. There was significant correlation of FVII.c activity with lipid markers, particularly among those with RR and RQ genotype after covariate adjustment. In conclusion, the F7 R353Q SNP appears to moderately influence plasma FVII.c activity and risk of CAD in Indians.     

Genetic evidence for distinct catalytic and regulatory subunits in yeast phosphofructokinase

Rat liver mitochondria contain an ATP-dependent proteolytic system which is localized on the outside of the inner membrane. It is capable of utilizating both the ATP produced within the mitochondria as well as that supplied externally. The system is dependent on Ca²⁺. Its physiological function is seen in the normal breakdown of mitochondria during their turnover. The system may be selective for the breakdown of the inner membranes.