Olmesartan, an AT1 antagonist, attenuates oxidative stress, endoplasmic reticulum stress and cardiac inflammatory mediators in rats with heart failure induced by experimental autoimmune myocarditis

Studies have demonstrated that angiotensin II has been involved in immune and inflammatory responses which might contribute to the pathogenesis of immune-mediated diseases. Recent evidence suggests that oxidative stress may play a role in myocarditis. Here, we investigated whether olmesartan, an AT(1)R antagonist protects against experimental autoimmune myocarditis (EAM) by suppression of oxidative stress, endoplasmic reticulum (ER) stress and inflammatory cytokines. EAM was induced in Lewis rats by immunization with porcine cardiac myosin, were divided into two groups and treated with either olmesartan (10 mg/kg/day) or vehicle for a period of 21 days. Myocardial functional parameters measured by hemodynamic and echocardiographic analyses were significantly improved by the treatment with olmesartan compared with those of vehicle-treated rats. Treatment with olmesartan attenuated the myocardial mRNA expressions of proinflammatory cytokines, [Interleukin (IL)-1β, monocyte chemoattractant protein-1, tumor necrosis factor-α and interferon-γ)] and the protein expression of tumor necrosis factor-α compared with that of vehicle-treated rats. Myocardial protein expressions of AT(1)R, NADPH oxidase subunits (p47phox, p67phox, gp91phox) and the expression of markers of oxidative stress (3-nitrotyrosine and 4-hydroxy-2-nonenal), and the cardiac apoptosis were also significantly decreased by the treatment with olmesartan compared with those of vehicle-treated rats. Furthermore, olmesartan treatment down-regulated the myocardial expressions of glucose regulated protein-78, growth arrest and DNA damage-inducible gene, caspase-12, phospho-p38 mitogen-activated protein kinase (MAPK) and phospho-JNK. These findings suggest that olmesartan protects against EAM in rats, at least in part via suppression of oxidative stress, ER stress and inflammatory cytokines.     

Non-Syndromic Hearing Impairment in India: High Allelic Heterogeneity among Mutations in TMPRSS3, TMC1, USHIC,CDH23 and TMIE

Mutations in the autosomal genes TMPRSS3, TMC1, USHIC, CDH23 and TMIE are known to cause hereditary hearing loss. To study the contribution of these genes to autosomal recessive, non-syndromic hearing loss (ARNSHL) in India, we examined 374 families with the disorder to identify potential mutations. We found four mutations in TMPRSS3, eight in TMC1, ten in USHIC, eight in CDH23 and three in TMIE. Of the 33 potentially pathogenic variants identified in these genes, 23 were new and the remaining have been previously reported. Collectively, mutations in these five genes contribute to about one-tenth of ARNSHL among the families examined. New mutations detected in this study extend the allelic heterogeneity of the genes and provide several additional variants for structure-function correlation studies. These findings have implications for early DNA-based detection of deafness and genetic counseling of affected families in the Indian subcontinent.     

Determinants of exclusive breastfeeding in rural South India

Background

While breastfeeding rates have improved globally, disparities in breastfeeding practices persist particularly in rural and low resource settings. In India, only 56% of Indian mothers practice exclusive breastfeeding (EBF) for the recommended six months. As India leads the world in the number of preterm births, under 5 years of age malnutrition and neonatal mortality, understanding the factors associated with EBF can help improve the nutritional status for millions of infants. We assessed the factors associated with EBF in rural Mysore, India.

Methods

This cross-sectional analysis was nested within a cohort study assessing the feasibility and uptake of mobile prenatal care and HIV counseling and testing intervention in Mysore District. Multivariable logistic regression was used to identify the factors associated with EBF for infants between birth and six months. Exclusive breastfeeding was defined as breastfeeding with no other liquids or breastfeeding substitutes given to infants exceptfor medicine or oral rehydration solution, between birth and 6 months and was assessed at six months postpartum.

Results

We surveyed mothers who delivered in rural Mysore taluk between 2008 and March 2011. A total of 1292 mothers participated in the study. The overall breastfeeding rate at six months postpartum was 74.9% and the EBF rate was 48.5%. Factors associated with EBF included higher maternal age (Adjusted Odds Ratio[aOR] 1.04; 95% Confidence Interval [CI] 1.00, 1.09), lower maternal education (aOR1.56, 95% CI 1.10, 2.21), and 7–10 antenatal visits (aOR 1.57; 95% CI 1.09, 2.27). The most common reason for non-exclusive breastfeeding was the mother’s feeling that she did not have enough milk (23.7%). Infants that were not exclusively breastfed were most commonly fed formula/animal milk (42.6%) or castor oil/ghee (18.4%).

Conclusions

Less than half of the mothers in our sample reported exclusive breastfeeding in a rural region of Karnataka, India in the first six months, a rate lower than national and state level rates. Future interventions should evaluate whether antenatal education can improve breastfeeding outcomes. The only modifiable factor was number of antenatal visits. Breastfeeding education should be emphasized at every antenatal visit so that even mothers with fewer than 7–10 antenatal visits can learn the best techniques and benefits of breastfeeding.

     

Large-scale expression of recombinant sialyltransferases and comparison of their kinetic properties with native enzymes

Values ofK _m were determined for three purified sialyltransferases and the corresponding recombinant enzymes. The enzymes were Gal1-4GlcNAc 2-6sialyltransferase and Gal1-3(4)GlcNAc 2-3sialyltransferase from rat liver; these enzymes are responsible for the attachment of sialic acid to N-linked oligosaccharide chains; and the Gal1-3GalNAc 2-3sialyltransferase from porcine submaxillary gland that is responsible for the attachment of sialic acid to O-linked glycoproteins and glycolipids. A procedure for the large scale expression of active sialyltransferases from recombinant baculovirus-infected insect cells is described. For the liver enzymes values ofK _m were determined using rat and human asialo₁ acid glycoprotein andN-acetyllactosamine as variable substrates; lacto-N-tetraose was also used with the Gal1-3(4)GlcNAc 2-3sialyltransferase. Antifreeze glycorprotein was used as the macromolecular acceptor for the porcine enzyme. Values forK _m were also determined using CMP-NeuAc as the variable substrate.Abbreviations NeuAc N-acetylneuraminic acid - Gal galactose - GlcNAc N-acetylglucosamine Enzymes: Gal1-4GlcNAc 2-6sialyltransferase, EC 2.4.99.1; Gal1-3(4)GlcNAc 2-3sialyltransferase, EC 2.4.99.5; Gal1-3GalNAc 2-3sialyltransferase, EC 2.4.99.4.     

Permanent Smears of Leaf Tips for the Study of Chromosomes

Young leaf tips are soaked in a saturated aqueous esculin (aesculine) solution at 10-12° C for 15 min to 24 hr and fixed in acetic-alcohol, 1:1. The materials are then stained in a mixture of 2% aceto-orcein and 12V HCl (9:1), 3-4 sec over a flame followed by 30 min or longer at 30° C and then smeared in 1% aceto-orcein. Preparations are made permanent by loosening the cover glass in tertiary butyl alcohol and mounting directly in Canada balsam.     

Mycobiome of the Bat White Nose Syndrome Affected Caves and Mines Reveals Diversity of Fungi and Local Adaptation by the Fungal Pathogen Pseudogymnoascus (Geomyces) destructans

Current investigations of bat White Nose Syndrome (WNS) and the causative fungus Pseudogymnoascus (Geomyces) destructans (Pd) are intensely focused on the reasons for the appearance of the disease in the Northeast and its rapid spread in the US and Canada. Urgent steps are still needed for the mitigation or control of Pd to save bats. We hypothesized that a focus on fungal community would advance the understanding of ecology and ecosystem processes that are crucial in the disease transmission cycle. This study was conducted in 2010–2011 in New York and Vermont using 90 samples from four mines and two caves situated within the epicenter of WNS. We used culture-dependent (CD) and culture-independent (CI) methods to catalogue all fungi (‘mycobiome’). CD methods included fungal isolations followed by phenotypic and molecular identifications. CI methods included amplification of DNA extracted from environmental samples with universal fungal primers followed by cloning and sequencing. CD methods yielded 675 fungal isolates and CI method yielded 594 fungal environmental nucleic acid sequences (FENAS). The core mycobiome of WNS comprised of 136 operational taxonomic units (OTUs) recovered in culture and 248 OTUs recovered in clone libraries. The fungal community was diverse across the sites, although a subgroup of dominant cosmopolitan fungi was present. The frequent recovery of Pd (18% of samples positive by culture) even in the presence of dominant, cosmopolitan fungal genera suggests some level of local adaptation in WNS-afflicted habitats, while the extensive distribution of Pd (48% of samples positive by real-time PCR) suggests an active reservoir of the pathogen at these sites. These findings underscore the need for integrated disease control measures that target both bats and Pd in the hibernacula for the control of WNS.