Biochanin A impedes STAT3 activation by upregulating p38δ MAPK phosphorylation in IL-6-stimulated macrophages

Inflammation Research - IL-6-induced STAT3 activation is associated with various chronic inflammatory diseases. In this study, we investigated the anti-STAT3 mechanism of the dietary polyphenol,...     

Dilated cardiomyopathy: a new insight into the rare but common cause of heart failure

Heart Failure Reviews - Heart failure is a global health burden responsible for high morbidity and mortality with a prevalence of greater than 60 million individuals worldwide. One of the major...     

Characterization of fibrillar collagen isoforms in infarcted mouse hearts using second harmonic generation imaging

We utilized collagen specific second harmonic generation (SHG) signatures coupled with correlative immunofluorescence imaging techniques to characterize collagen structural isoforms (type I and type III) in a murine model of myocardial infarction (MI). Tissue samples were imaged over a four week period using SHG, transmitted light microscopy and immunofluorescence imaging using fluorescently-labeled collagen antibodies. The post-mortem cardiac tissue imaging using SHG demonstrated a progressive increase in collagen deposition in the left ventricle (LV) post-MI. We were able to monitor structural morphology and LV remodeling parameters in terms of extent of LV dilation, stiffness and fiber dimensions in the infarcted myocardium.     

Cholera Toxin Production by the El Tor Variant of Vibrio cholerae O1 Compared to Prototype El Tor and Classical Biotypes

Vibrio cholerae O1 El Tor variant strains produced much more cholera toxin than did prototype El Tor strains. The amount of cholera toxin produced by El Tor variant strains both in vitro and in vivo was more or less equivalent to that produced by classical strains.Vibrio cholerae O1 is classified into classical and El Tor biotypes. Among other genetic, biochemical, and physiological differences, each biotype has unique gene sequences encoding cholera toxin B subunit (CTB), that is, classical ctxB and El Tor ctxB. Besides these two prototype biotypes of V. cholerae O1, Nair et al. (9) in 2002 in Bangladesh isolated strains that possess phenotypic properties of both classical and El Tor biotypes carrying classical ctxB. The same group also isolated El Tor strains that had classical ctxB (10). For these new types of strains of V. cholerae O1, we have recently proposed the designations of hybrid and El Tor variants, respectively (13). Subsequent to the isolation of the El Tor variant in Bangladesh by Nair et al. (10), El Tor variant strains were isolated from several countries and areas in Asia and Africa (1, 11, 15-18). In Kolkata, India, we showed that El Tor variant strains appeared in 1990 and that a complete replacement of prototype El Tor strains by El Tor variant strains has occurred since 1995 (14).In this study, we investigated the amount of cholera toxin (CT) produced both in vitro and in vivo by V. cholerae O1 El Tor variant strains isolated in Kolkata during a period from 1996 to 2007. It was found that El Tor variant strains produced a much larger amount of CT than did prototype El Tor strains and that the amount of CT produced by El Tor variant strains was more or less equivalent to that produced by classical strains.V. cholerae O1 strains used in this study are listed in Table ​Table1.1. AKI (3) and Syncase medium (2) were used for culturing the test strains. The rationale for selecting these media was that AKI preferentially supports the production of El Tor CT (3) while Syncase medium is reported to be the best medium supporting the production of CT by the classical biotype (2). Measurement of CT concentration produced by V. cholerae O1 strains was carried out as follows. Each strain was cultured either in AKI medium at 37°C for 20 h without shaking or in Syncase medium at 37°C for 20 h with shaking, and the optical density of the culture was measured at 600 nm (OD₆₀₀). After centrifugation, the supernatants were collected and the concentration of CT (ng/ml/OD₆₀₀) in the samples was measured by bead enzyme-linked immunosorbent assay (ELISA). The method of the bead ELISA employed was essentially that described by Oku et al. (12). In brief, a polystyrene bead (6.5 mm in diameter) was coated with anti-CT IgG and used as a solid phase. The coated bead was first incubated with the sample and then incubated with anti-CT IgG [F(ab′)]-horseradish peroxidase conjugate. Peroxidase activity was determined colorimetrically with 3,3′,5,5′-tetramethylbenzidine as the substrate. The absorbance at 450 nm (OD₄₅₀) was linear between 0 and 0.5, representing CT concentrations of 0 to 20 ng/ml. The sample prepared as described above (the supernatant of the culture of the strain) was appropriately diluted so that the OD₄₅₀ fell in the range of 0.1 to 0.5, and the amount of CT produced by the strain was expressed as ng/ml/OD₆₀₀.

TABLE 1.

V. cholerae O1 strains used

Lack of significant association between -1021C-->T polymorphism in the dopamine beta hydroxylase gene and attention deficit hyperactivity disorder

Recent trends in medications for attention deficit hyperactivity disorder (ADHD) suggest that norepinephrine (NE) deficiency may contribute to the disease etiology. Dopamine beta hydroxylase (DBH) is the key enzyme which converts dopamine to NE and since DBH gene is considered a major quantitative trait locus for plasma DBH activity, genetic polymorphism may lead to altered NE neurotransmission. Several polymorphisms including a 5' flanking -1021C-->T polymorphism, was reported to be associated with changed DBH activity and an association between -1021C-->T polymorphism with ADHD was observed in Han Chinese children. We have carried out family-based studies with three polymorphisms in the DBH gene, -1021C-->T polymorphism, exon 2*444g/a and intron 5 TaqI RFLP, to explore their association with Indian ADHD cases. Allele and genotype frequency of these polymorphisms in ADHD cases were compared with that of their parents and a control group. Haplotypes obtained were analyzed for linkage disequilibrium (LD). Haplotype-based haplotype relative risk analysis and transmission disequilibrium test showed lack of significant association between transmission of the polymorphisms and ADHD. A haplotype comprising of allele 1 of all polymorphisms showed a slight positive trend towards transmission from parents to ADHD probands. Strong LD was observed between *444g/a and TaqI RFLP in all the groups. However, low D' values and corresponding log of odds scores in the control group as compared to the ADHD families indicated that, the incidence of the two polymorphisms being transmitted together could be higher in ADHD families.     

Association of metabolic syndrome in polycystic ovarian syndrome: an observational study

Objectives

To find out the prevalence of metabolic syndrome (MBS) in women with PCOS and assess their strength of association. Methods: Total 50 apparently healthy non-pregnant PCOS subjects of 15 to 35 years were studied for having the features of MBS from May 2006 to April 2007. MBS was diagnosed by National Cholesterol Education Program’s Adult Treatment Panel III 2001 criteria. Student’s t test & Mann-Whitney U test were used for statistical analysis.

Results

21 subjects out of 50 (42%) met criteria for the MBS. 15(71.5%) belonged to 26–35 years and six (20.7%) in 15–25 years. Prevalence of waist circumference > 88 cm were noted in 34%, HDL cholesterol< 50 mg/dl in 50%, triglycerides ≥ 150 mg/dl in 40%, BP ≥130/85 mm Hg in 50% and FBS≥ 110 mg/dl in 16%. Women with higher insulin resistance and free testosterone levels significantly (P<0.01) correlated with higher prevalence of MBS.

Conclusion

The metabolic syndrome and its individual components are common in PCOS, particularly among women with hyperinsulinemia and hyperandrogenism.