Use of CHROMagar in the Differentiation of Common Species of <Emphasis Type="Italic">Candida</Emphasis>

CHROMagar has been reported to be useful for the rapid and accurate identification of Candida species. We tested 135 isolates of Candida species isolated from oropharyngeal candidiasis in HIV patients and found that it was useful in the presumptive identification of Candida albicans and Candida krusei. Occasional strains of C. tropicalis produced colonies with a greenish tinge making it difficult to differentiate from C. albicans.     

Dose-dependent effect of galangin on fructose-mediated insulin resistance and oxidative events in rat kidney

Galangin is an antioxidant flavonol present in high concentrations in the rhizome of Alpinia galanga. We investigated the effect of galangin on whole-body insulin resistance and kidney oxidative stress in a fructose-induced rat model of metabolic syndrome. Male albino Wistar rats were divided into 6 groups containing six animals each. Groups I and VI received a starch-based control diet, while groups II, III, IV and V were fed a high fructose diet (60 g/100 g). Groups III, IV and V additionally received galangin (50, 100 and 200 μg/kg body weight, respectively) while group VI received 200 μg galangin/kg body weight. At the end of 60 days, fructose-fed rats exhibited insulin resistance, increased levels of peroxidation end products and diminished antioxidant status. galangin, dose-dependently normalized blood glucose and insulin levels. The minimum effective dose was 100 μg galangin/kg body weight. At this dose, galangin also prevented the development of insulin resistance and the exaggerated the response to oral glucose challenge. The oxidant-antioxidant balance was maintained by galangin. Micro-albuminuria and tubular and glomerular changes observed in fructose-treated rats were significantly prevented by galangin (100 μg/kg body weight). These findings imply that galangin potentiates insulin sensitivity and antioxidant capacity and reduces renal damage in this dietary model of metabolic syndrome.     

Synthesis, pulse radiolysis, and in vitro radioprotection studies of melatoninolipoamide, a novel conjugate of melatonin and alpha-lipoic acid

A novel conjugate of melatonin 2 and alpha-lipoic acid 4 has been prepared using DCC mediated coupling. The conjugate named melatoninolipoamide has been assigned its structure 1 on the basis of spectral analysis (UV, IR, NMR, and EI-MS). Pulse radiolysis studies of the conjugate were carried out in aqueous solutions with both oxidizing and reducing radicals. The results indicate that the melatonin moiety of the conjugate reacts preferably with oxidizing radicals and the lipoic acid moiety exhibits preferential reaction with reducing radicals. The in vitro radioprotection ability of 1 was examined by gamma-radiation induced lipid peroxidation in liposomes and hemolysis of erythrocytes, and compared the results with those of melatonin and alpha-lipoic acid. The studies suggest that the conjugate can be explored as a probable radioprotector.     

Lysosomal localization of TRPML3 depends on TRPML2 and the mucolipidosis-associated protein TRPML1

Mucolipidosis type IV is an autosomal recessive lysosomal storage disorder characterized by severe neurodegeneration, achlorhydria, and visual impairments such as corneal opacity and strabismus. The disease arises due to mutations in a group 2 transient receptor potential (TRP)-related cation channel, TRPML1. Mammals encode two additional TRPML proteins named TRPML2 and TRPML3. Information regarding the propensity of these proteins to multimerize, their subcellular distribution and mechanisms that regulate their trafficking are limited. Here we demonstrate that TRPMLs interact to form homo- and heteromultimers. Moreover, the presence of either TRPML1 or TRPML2 specifically influences the spatial distribution of TRPML3. TRPML1 and TRPML2 homomultimers are lysosomal proteins, whereas TRPML3 homomultimers are in the endoplasmic reticulum. However, TRPML3 localizes to lysosomes when coexpressed with either TRPML1 or TRPML2 and is comparably mislocalized when lysosomal targeting of TRPML1 and TRPML2 is disrupted. Conversely, TRPML3 does not cause retention of TRPML1 or TRPML2 in the endoplasmic reticulum. These data demonstrate that there is a hierarchy controlling the subcellular distributions of the TRPMLs such that TRPML1 and TRPML2 dictate the localization of TRPML3 and not vice versa.     

Synthesis and photoluminescence properties of red emitting phosphor La2–xEuxLi0.5Al0.5O4 [x = 0.2–2] with K2NiF4 structure

Europium (Eu)³⁺‐substituted La₂Li_0.5Al_0.5O₄ red emitting phosphors were prepared by a conventional high‐temperature solid‐state reaction method. Powder X‐ray diffraction, diffuse reflectance spectra and spectrofluorometry were used as vital characterizing tools for the phosphors. The Eu concentration dependence luminescence properties and Judd–Ofelt intensity parameters were investigated and calculated, respectively. All compositions showed an orange red emission (due to the magnetic and electric dipole transitions of the Eu³⁺ ion) with the appropriate Commission Internationale de l'Eclairage (CIE) colour gamut under near ultraviolet or blue ray light excitation. The calculated critical distance showed that the energy transfer occured between Eu to Eu via an exchange mechanism. The Eu_1.4La_0.6Li_0.5Al_0.5O₄ composition showed the highest red emission intensity with CIE colour saturation compared with that of the commercial Eu‐activated yttrium oxysulfide red phosphor.     

Adaptive mechanisms to compensate for overnutrition-induced cardiovascular abnormalities

In conditions of overnutrition, cardiac cells must cope with a multitude of extracellular signals generated by changes in nutrient load (glucose, amino acids, and lipids) and the hormonal milieu [increased insulin (INS), ANG II, and adverse cytokine/adipokine profile]. Herein, we review the diverse compensatory/adaptive mechanisms that counter the deleterious effects of excess nutrients and growth factors. We largely focus the discussion on evidence obtained from Zucker obese (ZO) and Zucker diabetic fatty (ZDF) rats, which are useful models to evaluate adaptive and maladaptive metabolic, structural, and functional cardiac remodeling. One adaptive mechanism present in the INS-resistant ZO, but absent in the diabetic ZDF heart, involves an interaction between the nutrient sensor kinase mammalian target of rapamycin complex 1 (mTORC1) and ANG II-type 2 receptor (AT2R). Recent evidence supports a cardioprotective role for the AT2R; for example, suppression of AT2R activation interferes with antihypertrophic/antifibrotic effects of AT1R blockade, and AT2R agonism improves cardiac structure and function. We propose a scenario, whereby mTORC1-signaling-mediated increase in AT2R expression in the INS-resistant ZO heart is a cardioprotective adaptation to overnutrition. In contrast to the ZO rat, heart tissues of ZDF rats do not show activation of mTORC1. We posit that such a lack of activation of the mTOR?AT2R integrative pathway in cardiac tissue under conditions of obesity-induced diabetes may be a metabolic switch associated with INS deficiency and clinical diabetes.     

Influence of carbon-dioxide on the growth of Spirulina sp. (MCRC-A0003) isolated from Muttukadu backwaters,South India

Growth of Spirulina sp. (MCRC-A0003), a cyanobacterium, was evaluated under different concentrations of carbon-dioxide (CO₂) (4–50 %) in a closed glass photobioreactor. Although significant CO₂ utilization by the cyanobacterial strain was observed up to 50 % concentration, complete utilization was observed only at 4, 10 and 20 % concentrations on 3rd, 6th and 8th day respectively. However, considerable reduction was witnessed in reactors containing 30–50 % CO₂ only between 6th and 9th day. A corresponding increase in the biomass and primary metabolites like chlorophyll-a, carbohydrate and protein were observed. Biomass productivity of Spirulina in reactors sparged with 4, 10 and 20 % CO₂ were 13.7, 43 and 44 % more than that in control reactor without CO₂. While CO₂ increased the levels of primary metabolites in the cyanobacterial cells, it was quite prominent in 10 % CO₂ concentration with the chlorophyll-a, carbohydrate and protein contents were 64, 183 and 626 mg g^?1 respectively. While 10 and 6.6 % increase were noticed in chlorophyll-a and protein, 17 % increase in carbohydrate levels was observed in Spirulina cells, which could be attributed to the conversion of CO₂ to carbohydrate by the cyanobacterium.