Dysfunction of the ubiquitin ligase ube3a may be associated with synaptic pathophysiology in a mouse model of huntington disease

Huntington disease (HD) is a hereditary neurodegenerative disorder characterized by progressive cognitive, psychiatric, and motor symptoms. The disease is caused by abnormal expansion of CAG repeats in the gene encoding huntingtin, but how mutant huntingtin leads to early cognitive deficits in HD is poorly understood. Here, we demonstrate that the ubiquitin ligase Ube3a, which is implicated in synaptic plasticity and involved in the clearance of misfolded polyglutamine protein, is strongly recruited to the mutant huntingtin nuclear aggregates, resulting in significant loss of its functional pool in different regions of HD mouse brain. Interestingly, Arc, one of the substrates of Ube3a linked with synaptic plasticity, is also associated with nuclear aggregates, although its synaptic level is increased in the hippocampus and cortex of HD mouse brain. Different regions of HD mouse brain also exhibit decreased levels of AMPA receptors and various pre- and postsynaptic proteins, which could be due to the partial loss of function of Ube3a. Transient expression of mutant huntingtin in mouse primary cortical neurons further demonstrates recruitment of Ube3a into mutant huntingtin aggregates, increased accumulation of Arc, and decreased numbers of GluR1 puncta in the neuronal processes. Altogether, our results suggest that the loss of function of Ube3a might be associated with the synaptic abnormalities observed in HD.     

Expression, purification and development of neutralizing antibodies from synthetic BoNT/B LC and its application in detection of botulinum toxin serotype B

Botulism is a neuroparalytic disease caused by Clostridium botulinum, which produces seven (A-G) neurotoxins (BoNTs). The mouse bioassay is the gold standard for the detection of botulinum neurotoxins, however it requires at least 3-4 days for completion. Most of the studies were carried out in botulinum toxin A and less on type B. Attempts have been made to develop an ELISA based detection system, which is potentially an easier and more rapid method of botulinum neurotoxin detection. In the present study, the synthetic BoNT/B LC gene was constructed using PCR overlapping primers, cloned in a pET28a+ vector and expressed in E. coli BL21DE3. The maximum yield of recombinant proteins was optimized after 16 hrs of post induction at 21°C and purified the recombinant protein in soluble form. Antibodies were raised in Mice and Rabbit. The IgG antibody titer in the case of Mice was 1: 1,024,000 and Rabbit was 1: 512,000 with alum as adjuvant via intramascular route. The biological activity of the recombinant protein was confirmed by in-vitro studies using PC12 cells by the synaptobrevin cleavage, the rBoNT/B LC protein showed the maximum blockage of acetylcholine release at a concentration of 150nM rBoNT/B LC in comparison to the control cells. When the cells were incubated with rBoNT/B LC neutralized by the antisera raised against it, the acetylcholine release was equivalent to the control. IgG specific to rBoNT/B LC was purified from raised antibodies. The results showed that the developed antibody against rBoNT/B LC protein were able to detect botulinum toxin type B approximately up to 1 ng/ml. These developed high titer antibodies may prove useful for the detection of botulinum neurotoxins in food and clinical samples.     

Synthesis of 3-(1-alkyl/aminoalkyl-3-vinyl-piperidin-4-yl)-1-(quinolin-4-yl)-propan-1-ones and their 2-methylene derivatives as potential spermicidal and microbicidal agents

A series of twenty two derivatives of 3-(1-alkyl/aminoalkyl-3-vinyl-piperidin-4-yl)-1-(quinolin-4-yl)-propan-1-one and their 2-methylene derivatives were synthesized from naturally abundant cinchonine (I). Tartarate salts of these compounds were prepared and evaluated for spermicidal activity. The most active compounds (24, 27, 34, 36, and 38) showing potent spermicidal activity were further evaluated against different strains of Trichomonas vaginalis, for antimicrobial activity, in HeLa cell lines for cytotoxicity and against Lactobacillus jensenii for eco-safety. The tartarate of 3-(1-pentyl-3-vinyl-piperidin-4-yl)-1-(quinolin-4-yl)-propan-1-one (27) was found to be more active than N-9 in spermicidal activity.     

Association of educational, occupational and socioeconomic status with cardiovascular risk factors in asian indians: a cross-sectional study

Background

To determine correlation of multiple parameters of socioeconomic status with cardiovascular risk factors in India.

Methods

The study was performed at eleven cities using cluster sampling. Subjects (n = 6198, men 3426, women 2772) were evaluated for socioeconomic, demographic, biophysical and biochemical factors. They were classified into low, medium and high socioeconomic groups based on educational level (<10, 10–15 and >15 yr formal education), occupational class and socioeconomic scale. Risk factor differences were evaluated using multivariate logistic regression.

Results

Age-adjusted prevalence (%) of risk factors in men and women was overweight or obesity in 41.1 and 45.2, obesity 8.3 and 15.8, high waist circumference 35.7 and 57.5, high waist-hip ratio 69.0 and 83.8, hypertension 32.5 and 30.4, hypercholesterolemia 24.8 and 25.3, low HDL cholesterol 34.1 and 35.1, high triglycerides 41.2 and 31.5, diabetes 16.7 and 14.4 and metabolic syndrome in 32.2 and 40.4 percent. Lifestyle factors were smoking 12.0 and 0.5, other tobacco use 12.7 and 6.3, high fat intake 51.2 and 48.2, low fruits/vegetables intake 25.3 and 28.9, and physical inactivity in 38.8 and 46.1%. Prevalence of > = 3 risk factors was significantly greater in low (28.0%) vs. middle (23.9%) or high (22.1%) educational groups (p<0.01). In low vs. high educational groups there was greater prevalence of high waist-hip ratio (odds ratio 2.18, confidence interval 1.65–2.71), low HDL cholesterol (1.51, 1.27–1.80), hypertriglyceridemia (1.16, 0.99–1.37), smoking/tobacco use (3.27, 2.66–4.01), and low physical activity (1.15, 0.97–1.37); and lower prevalence of high fat diet (0.47, 0.38–0.57),overweight/obesity (0.68, 0.58–0.80) and hypercholesterolemia (0.79, 0.66–0.94). Similar associations were observed with occupational and socioeconomic status.

Conclusions

Low educational, occupational and socioeconomic status Asian Indians have greater prevalence of truncal obesity, low HDL cholesterol, hypertriglyceridemia, smoking or tobacco use and low physical activity and clustering of > = 3 major cardiovascular risk factors.     

Cis-by-Trans regulatory divergence causes the asymmetric lethal effects of an ancestral hybrid incompatibility gene

The Dobzhansky and Muller (D-M) model explains the evolution of hybrid incompatibility (HI) through the interaction between lineage-specific derived alleles at two or more loci. In agreement with the expectation that HI results from functional divergence, many protein-coding genes that contribute to incompatibilities between species show signatures of adaptive evolution, including Lhr, which encodes a heterochromatin protein whose amino acid sequence has diverged extensively between Drosophila melanogaster and D. simulans by natural selection. The lethality of D. melanogaster/D. simulans F1 hybrid sons is rescued by removing D. simulans Lhr, but not D. melanogaster Lhr, suggesting that the lethal effect results from adaptive evolution in the D. simulans lineage. It has been proposed that adaptive protein divergence in Lhr reflects antagonistic coevolution with species-specific heterochromatin sequences and that defects in LHR protein localization cause hybrid lethality. Here we present surprising results that are inconsistent with this coding-sequence-based model. Using Lhr transgenes expressed under native conditions, we find no evidence that LHR localization differs between D. melanogaster and D. simulans, nor do we find evidence that it mislocalizes in their interspecific hybrids. Rather, we demonstrate that Lhr orthologs are differentially expressed in the hybrid background, with the levels of D. simulans Lhr double that of D. melanogaster Lhr. We further show that this asymmetric expression is caused by cis-by-trans regulatory divergence of Lhr. Therefore, the non-equivalent hybrid lethal effects of Lhr orthologs can be explained by asymmetric expression of a molecular function that is shared by both orthologs and thus was presumably inherited from the ancestral allele of Lhr. We present a model whereby hybrid lethality occurs by the interaction between evolutionarily ancestral and derived alleles.     

Localization of PBP3 in Caulobacter crescentus is highly dynamic and largely relies on its functional transpeptidase domain

In rod-shaped bacteria, septal peptidoglycan synthesis involves the late recruitment of the ftsI gene product (PBP3 in Escherichia coli) to the FtsZ ring. We show that in Caulobacter crescentus, PBP3 accumulates at the new pole at the beginning of the cell cycle. Fluorescence recovery after photobleaching experiments reveal that polar PBP3 molecules are, constantly and independently of FtsZ, replaced by those present in the cellular pool, implying that polar PBP3 is not a remnant of the previous division. By the time cell constriction is initiated, all PBP3 polar accumulation has disappeared in favour of an FtsZ-dependent localization near midcell, consistent with PBP3 function in cell division. Kymograph analysis of time-lapse experiments shows that the recruitment of PBP3 to the FtsZ ring is progressive and initiated very early on, shortly after FtsZ ring formation and well before cell constriction starts. Accumulation of PBP3 near midcell is also highly dynamic with a rapid exchange of PBP3 molecules between midcell and cellular pools. Localization of PBP3 at both midcell and pole appears multifactorial, primarily requiring the catalytic site of PBP3. Collectively, our results suggest a role for PBP3 in pole morphogenesis and provide new insights into the process of peptidoglycan assembly during division.     

Diverse mechanisms adopted by fluorescent <Emphasis Type="Italic">Pseudomonas</Emphasis> PGC2 during the inhibition of <Emphasis Type="Italic">Rhizoctonia solani</Emphasis> and <Emphasis Type="Italic">Phytophthora capsici</Emphasis>

Rhizoctonia solani and Phytophthora capsici are two of the most destructive phytopathogens occurring worldwide and are only partly being managed by traditional control strategies. Fluorescent Pseudomonas isolates PGC1 and PGC2 were checked for the antifungal potential against R. solani and P. capsici. Both the isolates were screened for the ability to produce a range of antifungal compounds. The results of this study indicated the role of chitinase and β-1,3-glucanase in the inhibition of R. solani, however, antifungal metabolites of a non-enzymatic nature were responsible for inhibition of P. capsici. The study confirmed that multiple and diverse mechanisms are adopted by the same antagonist to suppress different phytopathogens, as evidenced in case of R. solani and P. capsici.     

Modulation of haloperidol induced electrophysiological alterations on cardiac action potential by various risk factors and gender difference

Haloperidol (HPL), well known antipsychotic drug can induce a marked QT prolongation and polymorphic arrhythmias. In this study we evaluated the influence of various induced risk factors such as electrolyte imbalance (hypokalemia and hypomagnesemia), gender difference, low pacing frequency, ischemia reperfusion insult on electrophysiological effect by haloperidol on electrically driven action potentials recorded from guinea pig papillary muscle. The doses of HPL ranging from 1 to 16 μM were used in this investigation. Action potentials (APs) were elicited electrically and recorded by classical microelectrode technique. HPL caused dose dependent prolongation of APD₉₀ the final stage of repolarization, increased triangulation, and led into dispersion of action potential, conduction delay and conduction block. Magnitude of the effect of haloperidol was amplified significantly by most of the risk factors. Among the various risk factors, electrolyte imbalance (hypokalemia, hypomagnesemia) caused more amplification of HPL effect. Most of the risk factors amplified prolongation of APD₉₀ by HPL. This effect is mainly due to the influence of these electrolytes and sex hormone on various ion channels involved in the repolarization phase of cardiac AP. This is the first report which provides an experimental evidence of amplification of electrophysiological effects of HPL in the presence of various risk factors.