Improvement in metal vapor laser performance with reduction in localized electric field at electrodes.

Electrode geometry plays a vital role in metal vapor laser performance. It has been observed that by modifying the electrode geometry, the electric field enhancement near the electrode can be reduced. Reduction in the localized electric field causes reduction in the phantom current in the metal vapor laser. On replacing the electrode geometry having eight pins with an electrode having the zero-pin configuration, a 10% decrease in the phantom current and a 23% increase in optical output power are observed. The low phantom current is responsible for higher efficiencies, large specific average output power, and improved beam characteristics of that laser in reference to a conventional copper vapor laser. It was also observed that reduction in field enhancement causes reduction in the thermal loading at the cathode fall and in the probability of thermal instability, thereby improving the discharge stability and jitter in metal vapor lasers. This simple and effective technique can also be applied to the systems requiring high current and high-volume stable discharge.

Cissus quadrangularis Linn exerts dose-dependent biphasic effects: osteogenic and anti-proliferative, through modulating ROS, cell cycle and Runx2 gene expression in primary rat osteoblasts.

OBJECTIVES: This report highlights phytoconstituents present in Cissus quadrangularis (CQ) extract and examines biphasic (proliferative and anti-proliferative) effects of its extract on bone cell proliferation, differentiation, mineralization, ROS generation, cell cycle progression and Runx2 gene expression in primary rat osteoblasts. MATERIALS AND METHODS: Phytoconstituents were identified using gas chromatography-mass spectroscopy (GC-MS). Osteoblasts were exposed to different concentrations (10-100 µg/ml) of CQ extract and cell proliferation and cell differentiation were investigated at different periods of time. Subsequently, intracellular ROS intensity, apoptosis and matrix mineralization of osteoblasts were evaluated. We performed flow cytometry for DNA content and real-time PCR for Runx2 gene expression analysis. RESULTS: CQ extract's approximately 40 bioactive compounds of fatty acids, hydrocarbons, vitamins and steroidal derivatives were identified. Osteoblasts exposed to varying concentrations of extract exhibited biphasic variation in cell proliferation and differentiation as a function of dose and time. Moreover, lower concentrations (10-50 µg/ml) of extract slightly reduced ROS intensity, although they enhanced matrix mineralization, DNA content in S phase of the cell cycle, and levels of Runx2 expression. However, higher concentrations (75-100 µg/ml) considerably induced the ROS intensity and nuclear condensation in osteoblasts, while it reduced mineralization level, proportion of cells in S phase and Runx2 level of the osteogenic gene. CONCLUSIONS: These findings suggest that CQ extract revealed concentration-dependent biphasic effects, which would contribute notably to future assessment of pre-clinical efficacy and safety studies.

Measles outbreak investigation in Dwarahat block of District Almora, Uttarakhand.

BACKGROUND: We report an assessment of measles outbreak during the months of February 2014 to April 2014 in Dwarahat block of district Almora and the response mounted to it. MATERIALS AND METHODS: An intensive door-to-door search to six measles affected villages in Dwarahat block of district Almora, covering a population of 2,408 was carried out to identify the cases of measles by a rapid response team (RRT). A total of ten blood samples were randomly collected for detecting IgM antibody against measles. For all cases, information on personal details, place of residence, time of onset and status of immunization were obtained. RESULTS: Overall attack rate (AR) was 2.8%. AR among the population of age-group 0-16 was 7.2%. Statistically significant higher AR (16.26%) was seen for the age-group of 0-5 years as compare to 6-10 and 11-16 years of age (AR-8.71, relative risk-0.53, 95% confidence interval-0.32-0.88, P value-0.012 and AR-0.57%, relative risk-0.035, 95% confidence interval-0.00-0.14, P value-0.000, respectively). Males were affected more often than females 35 [59.2%] vs. 24 [40.8%]. Measles-related complications were seen in three children. No death was reported. Of the 10 samples, nine were positive for measles IgM antibodies by enzyme-linked immunosorbent assay (ELISA). CONCLUSION: The recognition of early warning signals, timely investigation and application of specific control measures can contain the outbreak. The unvaccinated or partially protected human beings serve as the reservoir of measles virus. Hence, there is a need for sero surveillance for measles in Uttarakhand and one catch up measles immunisation campaign to prevent future outbreak.

In silico and in vivo analysis of binding affinity of estrogens with estrogen receptor alpha in Channa punctatus (Bloch).

In the present study, potential interaction between natural estrogens i.e., estrone (E(1)), estradiol (E(2)) and estriol (E(3)) with human estrogen receptor (hER) was seen by in silico study. Molecular docking studies were carried out using Glide and ligand docking program. The binding affinity, assessed by Glide score, indicates stronger interaction of E(3) with hER followed by E(2) and E(1). Real-time PCR analysis of vga and vgb expressions, in the liver of different groups of Channa punctatus injected with the three natural estrogens, supported the docking analysis and indicated E(3) to be the most potent estrogen in inducing vga and vgb expressions followed by E(2) and E(1). This study lays the groundwork for studying interactions of various estrogenic substances with different estrogen receptors and to assess estrogenicity of various chemicals which are being released into the environment by employing molecular docking technique.

Characterization of incomplete vitellogenin (VgC) in the Indian freshwater murrel, Channa punctatus (Bloch).

A novel incomplete vitellogenin (VgC) was purified from the plasma of estradiol-treated male murrel, Channa punctatus, by gel filtration chromatography. The native mass of VgC protein was 180 kDa, and it resolved as a single peptide of 100 kDa on SDS-PAGE. The peptide on subjecting to matrix-assisted laser desorption/ionization-time of flight produced a peptide mass fingerprint. On tandem mass spectrometry, some of these peptides showed mass to charge (m/z) ratio and amino acid sequence similarity with VgC peptides of other teleosts. Phylogenetic analysis revealed a similarity of murrel VgC with fish species of the order Perciformes. Semi-quantitative RT-PCR assay was developed to study expression of vgc gene at variable levels of estradiol exposure. Presence of VgC in males indicates that fish has been exposed to estrogens; hence, it can be used as a biomarker for estrogenic exposure.

The leukemogenicity of Hoxa9 depends on alternative splicing.

Although the transforming potential of Hox genes is known for a long time, it is not precisely understood to which extent splicing is important for the leukemogenicity of this gene family. To test this for Hoxa9, we compared the leukemogenic potential of the wild-type Hoxa9, which undergoes natural splicing, with a full-length Hoxa9 construct, which was engineered to prevent natural splicing (Hoxa9FLim). Inability to undergo splicing significantly reduced in vivo leukemogenicity compared to Hoxa9-wild-typed. Importantly, Hoxa9FLim could compensate for the reduced oncogenicity by collaborating with the natural splice variant Hoxa9T, as co-expression of Hoxa9T and Hoxa9FLim induced acute myeloid leukemia (AML) after a comparable latency time as wild-type Hoxa9. Hoxa9T on its own induced AML after a similar latency as Hoxa9FLim, despite its inability to bind DNA. These data assign splicing a central task in Hox gene mediated leukemogenesis and suggest an important role of homeodomain-less splice variants in hematological neoplasms.

Purification, characterization and expression of two vitellogenins in the Indian freshwater murrel Channa punctatus.

The present study was undertaken to characterize different vitellogenins in Channa punctatus. Protein purification by gel chromatography followed by fast protein liquid chromatography (FPLC) revealed existence of two different Vg forms. Liquid chromatography tandem mass spectrophotometry (LC-MS/MS) suggested the existence of Vga and Vgb. Cloning of partial sequences of vga and vgb mRNA and phylogenetic analysis substantiated the existence of two vitellogenins. Real time PCR for vga and vgb genes from liver of estradiol-17ß (E2) treated fish reveals difference in expression levels of transcripts of these two genes. vgb is expressed at lower dose of estradiol suggesting a higher sensitivity to estradiol. The present study thus proposes different regulatory control for the expression of these two genes and vgb as a superior biomarker than vga to assess exposure of C. punctatus to environmental estrogens.

Vitellogenin genes in fish: differential expression on exposure to estradiol.

Three types of vitellogenins (Vgs) namely vitellogenin A (VgA), vitellogenin B (VgB) and vitellogenin C (VgC) have been identified in fishes. The existence of VgA and VgB is reported in the Indian freshwater murrel Channa punctatus. Gene-specific primers were designed using available nucleotide sequences in National Centre for Biotechnology Information (NCBI), for amplification of VgA and VgB cDNA. Differential processing of Vgs is evident in many fishes. Adult male murrel expressed both the VgA and VgB genes when estradiol-17ß (E(2)) is injected in vivo and Vg levels in blood quantified by Enzyme linked immunosorbent assay (ELISA) showed a dose-related response in such treatments. Cultured hepatocytes on treatment with E(2), however, expressed only VgB as detected by RT-PCR, suggesting different regulatory mechanism for the VgA and VgB genes.

Vitamin D replacement in pregnant women in rural north India: a pilot study.

Hypovitaminosis D is common in both urban and rural Indians. The dose of vitamin D needed for the treatment of its deficiency during pregnancy is not clear. We conducted a study in rural Indians to evaluate the effect of cholecalciferol supplementation during routine antenatal visits on maternal 25 hydroxyvitamin D (25OHD) at delivery. Pregnant women received either no cholecalciferol (Group A) or 60 000 U (Group B) in the fifth month of gestation or 120 000 U each in the fifth and seventh gestational months (Group C). Serum 25OHD was measured at baseline (n=139) and at delivery (n=84). Median (interquartile range) 25OHD at baseline was low: 32.3 nmol/l (22.8-50.1 nmol/l). A significant increase in 25OHD at delivery was obtained only in group C: 40.1 nmol/l (26.9-58.4 nmol/l) at baseline vs 53.4 nmol/l (41.2-88.0 nmol/l) after delivery, P<0.001. Only 20% of participants in Group C achieved 25OHD at delivery >80 nmol/l, not significantly different from Group B. Cholecalciferol in doses of 120 000 U each in fifth and seventh gestational months was effective in raising 25OHD at delivery.

The homeobox gene CDX2 is aberrantly expressed and associated with an inferior prognosis in patients with acute lymphoblastic leukemia.

Molecular characterization of acute lymphoblastic leukemia (ALL) has greatly improved the ability to categorize and prognostify patients with this disease. In this study, we show that the proto-oncogene CDX2 is aberrantly expressed in the majority of cases with B-lineage ALL and T-ALL. High expression of CDX2 correlated significantly with the ALL subtype pro-B ALL, cALL, Ph(+) ALL and early T-ALL. Furthermore, high expression of CDX2 was associated with inferior overall survival and showed up as a novel and strong risk factor for ALL in bivariate analysis. Functional analyses showed that overexpression of Cdx2 in murine bone marrow progenitors perturbed genes involved in lymphoid development and that depletion of CDX2 in the human ALL cell line Nalm6 inhibited colony formation. These data indicate that aberrant CDX2 expression occurs frequently and has prognostic impact in adult patients with ALL.

Candida colonization in preterm babies admitted to neonatal intensive care unit in the rural setting.

PURPOSE: Candida colonization in neonates results in significant morbidity and mortality. The purpose of this study was to determine colonization of Candida spp. in preterm babies and identify the risk factors. METHODS: Swabs from oral, rectum, groin and umblicus of 103 preterm and 100 term neonates were obtained within 24 hours of birth, day three, day five, day seven and thereafter every week till the neonate was admitted in the neonatal intensive care unit (NICU). Swabs were also collected from the mother's vagina prior to delivery. Twice every month, air of the NICU was sampled by settle plate and swabs were collected from the hands of health care workers and inanimate objects of NICU. Identification and speciation was done by standard methods. Antibiotic sensitivity was studied against amphotericin B, ketoconazole and fluconazole by disk diffusion method. RESULTS: Colonization with Candida was significantly higher in preterms. Earliest colonization was of oral mucosa and 77.1% of the preterms had colonised at various sites by the first week of life. Significant risk factors in colonized versus non-colonized preterms were male sex, longer duration of rupture of membranes (DROM), administration of steroids and antibiotics and vaginal colonization of mothers, whereas those in preterms versus terms were low birth weight and gestational age. C. albicans was the commonest species, both in the colonized preterms (45.9%) and vagina of mothers. Resistance was seen to fluconazole and ketoconazole only. No Candida spp. was isolated from health care personnel or environment. CONCLUSIONS: Colonization of preterms by Candida is a significant problem in NICU and the significant risk factors observed in colonized preterms were male sex, longer DROM, administration of steroids and antibiotics and vaginal colonization of mothers.

Characterization of the antiapoptotic (p35) gene homologue of Spodoptera litura nucleopolyhedrosis virus (SlNPV).

Antiapoptotic genes of baculoviruses have been shown to prevent virus induced apoptosis in insect cells. Dot blot and Southern hybridizations of EcoRI genomic library and genomic digests of Spodoptera litura nucleopolyhedrosis virus (SlNPV) respectively give strong hybridization signals with antiapoptotic DNA (p35 gene) probe of the prototype Autographa californica nucleopolyhedrosis virus (AcNPV). Both the hybridizations indicate the presence of a homologous gene in the 1.8 kb EcoRI-Y fragment of SlNPV. The sequence of 1.244 kb region of this fragment encompasses an open reading frame coding for a polypeptide of 296 amino acids under sequential early (TATA) and late (TAAG) promoter motifs like that in other baculovirus p35 genes. The putative SlNPV p35 ORF expresses abundantly as a 35 kDa protein in Spodopterafrugiperda (Sf9) cells when allowed to express under the polyhedrin promoter of AcNPV.