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BACKGROUND: Cholera, an infectious disease caused by Vibrio cholerae, is a major public health problem and is a particularly burden in developing countries including Nepal. Although the recent worldwide outbreaks of cholera have been due to V. cholerae El Tor, the classical biotypes are still predominant in Nepal. Serogroup O1 of the V. cholerae classical biotype was the primary cause of a cholera outbreak in Kathmandu in 2012. Thus, this study was designed to know serotypes and biotypes of V. cholerae strains causing recent outbreak with reference to drug resistant patterns. Moreover, we also report the toxigenic strains of V. cholerae from both environmental and clinical specimens by detecting the ctx gene. METHODS: Twenty four V. cholerae (n = 22 from stool samples and n = 2 from water samples) isolated in this study were subjected to Serotyping and biotyping following the standard protocols as described previously. All of the isolates were tested for antimicrobial susceptibility patterns using the modified Kirby-Bauer disk diffusion method as recommended by CLSI guidelines. The screening of the ctx genes (ctxA2-B gene) were performed by PCR method using a pair of primers; C2F (5'-AGGTGTAAAATTCCTTGACGA-3') and C2R (5'-TCCTCAGGGTATCCTTCATC-3') to identify the toxigenic strains of V. cholerae. RESULTS: Among twenty four V. cholerae isolates, 91.7% were clinical and 8.3% were from water samples. Higher rate of V. cholerae infection was found among adults of aged group 20-30 years. All isolates were serogroups O1 of the V. cholerae classical biotype and sub serotype, Ogawa. All isolates were resistant to ampicillin, nalidixic acid and cotrimoxazole. 90.9% were resistant to erythromycin however, tetracycline was found to be the most effective drug for the isolates. All isolates were multidrug resistant (MDR) and possessed a ctx gene of approximately 400 base pairs indicating the toxigenic strains. CONCLUSION: Hundred percent strains of V. cholerae were MDR possessing a ctx gene. It suggests that toxigenic strains be identified and proper antibiotic susceptibility testing be conducted. This will allow effective empirical therapy to be used to treat and control cholera.

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Effective atomic numbers of some human organ tissue substitutes such as polyethylene terephthalate, red articulation wax, paraffin 1, paraffin 2, bolus, pitch, polyphenylene sulfide, polysulfone, polyvinylchloride, and modeling clay have been calculated by four different methods like Auto-Zeff, direct, interpolation, and power law. It was found that the effective atomic numbers computed by Auto-Zeff, direct and interpolation methods were in good agreement for intermediate energy region (0.1 MeV < E < 5 MeV) where the Compton interaction dominates. A large difference in effective atomic numbers by direct method and Auto-Zeff was observed in photo-electric and pair-production regions. Effective atomic numbers computed by power law were found to be close to direct method in photo-electric absorption region. The Auto-Zeff, direct and interpolation methods were found to be in good agreement for computation of effective atomic numbers in intermediate energy region (100 keV < E < 10 MeV). The direct method was found to be appropriate method for computation of effective atomic numbers in photo-electric region (10 keV < E < 100 keV). The tissue equivalence of the tissue substitutes is possible to represent by any method for computation of effective atomic number mentioned in the present study. An accurate estimation of Rayleigh scattering is required to eliminate effect of molecular, chemical, or crystalline environment of the atom for estimation of gamma interaction parameters.

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A comprehensive study of gamma-ray exposure build-up factors (EBFs) of fly-ash brick materials has been carried out for photon energies of 0.015-15 MeV up to a penetration depth of 40 mfp (mean free path) by a geometrical progression (GP) fitting method. The EBF values of the fly-ash brick materials were found to be dependent upon the photon energy, penetration depth and chemical composition, and were found to be higher than the values for mud bricks and common bricks. Above a photon energy of 3 MeV for large penetration depths (>10 mfp), the EBF becomes directly proportional to Zeq. EBFs of fly-ashes were found to be less than or equal to those of concrete for low penetration depths (<10 mfp) for intermediate photon energies up to 1.5 MeV. The EBF values of fly-ash materials were found to be almost independent of Si concentration. The fast neutron removal cross sections of the fly-ash brick materials, mud bricks and common bricks were also calculated to understand their shielding effectiveness. The shielding effectiveness of the fly-ash materials against gamma-ray radiation was lower than that of common and mud bricks.

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In a randomized controlled trial, a daily Oral Vitamin D supplementation was given in dose of 2000 IU for Group A, 1000 IU for Group B , 500 IU for Group C and placebo for Group D over 3 months period to assess the anti-inflammatory effect of vitamin D on gingivitis at various doses. The changes in gingival scores were measured at the period of 1 st , 2 nd and 3 rd month. Gingivitis score changed in direct proportion to the dose of vitamin D supplementation. Group A mean gingival scores were 2.4 (baseline); 1.7 (1 st month), 0.8 (2 nd month) and 0.3 (3 rd month). The group B the mean baseline gingival score from 2.3 reduced to 2.0 (month), 1.1 (two months) and 0.5 (third month). Group C had baseline gingival scores of 2.2 and 1.9 (1 st month), 1.4 (2 nd month) and 0.8 (last visit). Comparing baseline gingivitis scores with later visit score by Wilcoxon paired test, the anti-inflammatory effect was significantly seen in group A after one month itself, group B at two months and group C at 3 rd month after oral vitamin D supplementation. However, Group D did not show any significant anti-inflammatory effect.

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Direct reading dosemeter has been used for day-to-day radiation exposure control and management for last four decades in Indian nuclear power plants (NPPs). Recently new real time, alarm and pre-alarm on equivalent dose/dose rate, storage of dose/dose rate and maximum dose rate, user-friendly electronic active personal dosemeter (APD) has been implemented into practice for the first time at Kaiga Atomic Power Station-3&4,  of Indian NPPs. The dosemeter showed tolerance level (L) 0.1085±0.0450 compared with 0.1869±0.0729 (average±SD) for CaSO4:Dy, TL dosemeter, having narrow range trumpet curve, nil electromagnetic interference. Records of >29 000 for APD and TL dosemeter were analysed for comparasion of the measurement of the individual dose. APD followed general acceptance rule of ±25 % for dose >1 mSv. Monthly Station collective dose by TL dosemeters and APD for normal reactor operation as well as outage are found in good agreement. Operational experiences and statistical analysis support that an APD dosemeter is reasonably equivalent to CaSO4:Dy TL dosemeter. The accuracy, reproducibility and repeatability of the measurement of radiation for (137)Cs are comparable with CaSO4:Dy, TL dosemeter. Operational experience of APD during the normal operation as well as outage showed as one of the best ALARA tool for occupational dose monitoring, control, management and future outage planning.

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PURPOSE: To assess the anti-inflammatory effect of vitamin D on gingivitis at various doses. MATERIALS AND METHODS: In this randomized controlled trial, daily oral vitamin D supplementation was given in doses of 2000 IU for group A, 1000 IU for group B, 500 IU for group C and a placebo for group D over a 3-month period. The changes in gingival scores were measured after the 1st, 2nd and 3rd months. RESULTS: The gingivitis score changed in direct proportion to the dose of vitamin D supplementation. In group A, the mean gingival scores were 2.4 (baseline), 1.7 after the first month, 0.8 after the second month and 0.3 after the third month. The group B mean baseline gingival score of 2.3 decreased to 2.0 in the first month, 1.1 after the second month and 0.5 after the third month. In group C, the baseline gingival scores were 2.2 and 1.9 after one month, 1.4 after two months and 0.8 by the last visit. Comparing baseline gingivitis scores with the later-visit score using the Wilcoxon paired test, the significant anti-inflammatory effect was seen in group A after one month, in group B at two months and in group C at three months after oral vitamin D supplementation (P < 0.0001). However, group D did not show a significant antiinflammatory effect. CONCLUSION: There is a dose-dependent anti-inflammatory effect of vitamin D on gingivitis. Vitamin D is a safe and effective anti-inflammatory agent in doses ranging from 500 IU to 2000 IU. Results are apparent earlier with the higher dose of 2000 IU.

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Removal half-life (RHL) of tritium is one of the best means for optimising medical treatment, reduction of committed effective dose (CED) and quick/easy handling of a large group of workers for medical treatment reference. The removal of tritium from the body depends on age, temperature, relative humidity and daily rainfall; so tritium removal rate, its follow-up and proper data analysis and recording are the best techniques for management of accidental acute tritium exposed cases. The decision of referring for medical treatment or medical intervention (MI) would be based on workers' tritium RHL history taken from their bodies at the facilities. The workers with tritium intake up to 1 ALI shall not be considered for medical treatment as it is a derived limit of annual total effective dose. The short-term MI may be considered for tritium intake of 1-10 ALI; however, if the results show intake ≥100 ALI, extended strong medical/therapeutic intervention may be recommended based on the severity of exposure for maximum CED reduction requirements and annual total effective dose limit. The methodology is very useful for pressurized heavy water reactors (PHWRs) which are mainly operated by Canada and India and future fusion reactor technologies. Proper management will optimise the cases for medical treatment and enhance public acceptance of nuclear fission and fusion reactor technologies.

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Given the essential role of proteomics in understanding the biology of plants, we are establishing a global plant proteomics organization to properly organize, preserve and disseminate collected information on plant proteomics. We call this organization 'International Plant Proteomics Organization (INPPO; http://www.inppo.com).' Ten initiatives of INPPO are outlined along with how to address them in multiple phases. As our vision is global, we sincerely hope the scientific communities around the world will come together to support and join INPPO.

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The present study estimates biological half-life (BHL) of tritium by analysing routine bioassay samples of radiation workers. During 2007-2009 year, 72,100 urine bioassay samples of the workers were analysed by liquid scintillation counting technique for internal dose monitoring for tritium. Two hundred and two subjects were taken for study with minimum 3 µCiL(-1) tritium uptake in their body fluid. The BHL of tritium of subjects ranges from 1 to 16 d with an average of 8.19 d. Human data indicate that the biological retention time ranges from 4 to 18 d with an average of 10 d. The seasonal variations of the BHL of tritium are 3.09 ± 1.48, 6.87 ± 0.58 and 5.73 ± 0.76 d (mean ± SD) for summer, winter and rainy seasons, respectively, for free water tritium in the coastal region of Karnataka, India, which shows that the BHL in summer is twice that of the winter season. Also three subjects showed the BHL of 101.73-121.09 d, which reveals that organically bound tritium is present with low tritium uptake also. The BHL of tritium for all age group of workers is observed independent of age and is shorter during April to May. The distribution of cumulative probability vs. BHL of tritium shows lognormal distribution with a geometric mean of 9.11 d and geometric standard deviation of 1.77 d. The study of the subjects is fit for two-compartment model and also an average BHL of tritium is found similar to earlier studies.

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Higher rates of glucose usage generally correlate with poor prognosis in several types of malignant tumours. Experimental studies (both in vitro and in vivo) have shown that 2-deoxy-D-glucose (2-DG), a glucose analog and glycolytic inhibitor, enhances radiation-induced damage selectively in tumor cells while protecting normal cells, thereby suggesting that 2-DG can be used as a differential radiomodifier to improve the efficacy of radiotherapy. Clinical trials undertaken to study the feasibility, safety, and validity of this suggested approach will be described. Based on 2-DG-induced radiosensitization observed in primary organ cultures of cerebral glioma tissues, clinical trials were designed taking into consideration the radiobiology of gliomas and pharmacokinetics of 2-DG. Phase I/II clinical trials have unequivocally demonstrated that a combination of 2-DG (200-300 mg 2-DG per kg body weight orally administered after overnight fasting, 20 min before irradiation) with large weekly fractions (5 Gy/fraction) of low-LET radiotherapy is well tolerated without any acute toxicity or late radiation damage to the normal brain tissue. Nonserious transient side effects similar to hypoglycemia induced disturbances like restlessness, nausea, and vomiting were observed at the 2-DG doses used. Data from these trials involving more than 100 patients have clearly indicated a moderate increase in the survival, with a significant improvement in the quality of life with clinicopathological evidence of protection of normal brain tissue. A phase III multicentric trial to evaluate the efficacy of the combined treatment is in progress. Directions for future studies are discussed.

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AIMS AND OBJECTIVES: Diabetes mellitus (DM) is often termed as a disease of premature aging. Several studies have indicated lopsided redox balance due to pro oxidant environment as one of the important etiological factors. Some recent researches also indicate a causal relationship with oxidative stress (OS). So far, no study has been undertaken on this aspect in Nepali populations. We, therefore, aimed this maiden study in Nepali population to examine redox balance by measuring OS and antioxidant status along with lipid profile in 37 patients of DM type- 2 and 30 matched normal subjects. METHODOLOGY: Thirty seven patients of DM type-2 without any complications (mean age= 57.6+/- 10.6 years) and 30 normal subjects (mean age= 55.8 +/- 14.8 years) were included in this study. Body Mass Index (BMI) and Waist/Hip (W/H) ratio were measured. Fasting blood sample was collected for the analysis of total antioxidant activity (TAA), plasma and urinary thiobarbituric acid reactive substances (TBARS) and lipid profile by standard procedures in both the groups. The statistical analysis was done with SPSS 10 version. RESULTS: Total cholesterol, triglyceride, VLDL-cholesterol, LDL-cholesterol, plasma and urinary TBARS were significantly raised whereas, plasma TAA was significantly reduced in DM type-2 patients as compared to controls. The comparison of old and fresh cases revealed that though TAA was lower and PTBARS and UTBARS were higher in patients but did not attain the level of significance. W/H ratio is significantly higher in patients compared to normal subjects. But, no significant correlation of BMI and W/H with lipid profile is observed in both control and patients. CONCLUSION: Oxidative stress is raised in type 2 DM patients. This along with deranged lipid profile and decreased antioxidant status could be the risk factors in the development of complications associated with DM.

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OBJECTIVES: To assess the effect of cigarette smoking on lipid peroxidation induced oxidative stress, antioxidants, uric acid and blood sugar in normal subjects. METHODS: The study included 61 normal subjects with regular smoking habit and 57 never-smokers normal subjects matched in respect to socio-economic status, age and BMI. Information regarding smoking habit and other personal details were collected by oral questionnaire. Total antioxidant activity (TAA), reduced glutathione (GSH), alpha-tocopherol (alpha-T), ascorbic acid (AA), uric acid (UA), plasma and urinary thiobarbituric acid reactive substances (TBARS), fasting blood sugar (FBS) and urinary creatinine (Cr) were estimated by standard procedures in both the groups. Ferric Reducing Antioxidant Power (FRAP) procedure is used to estimate TAA which measures total dietary antioxidants. Statistical analysis was done with SPSS version 10. RESULTS: The mean pack years smoked by smokers was 14.4 +/- 15.8. The plasma TBARS level in smokers and never-smokers was 2.6 +/- 0.8 and 2.5 +/- 0.6 micromol/L respectively. The respective figure for urinary TBARS level was 4.6 +/- 2.7 and 3.7 +/- 1.4 micromol/gmCr. Smokers did not show any significant difference from never-smokers with respect to GSH, alpha-T, AA, plasma TBARS and FBS. However, the smokers had significantly lower levels of TAA (p<0.05) and raised level of urinary TBARS (p<0.05) and uric acid (p<0.01) as compared to never-smokers. CONCLUSION: Our study suggests that smoking induces mild lipid peroxidation but the body is able to compensate for it by removing its adducts. Importantly it also indicates enhanced oxidation of purines which are essential components of both DNA and RNA. Dietary antioxidants are consumed to scavenge free radicals (FR) and other reactive species (RS) in smoke. Female smokers are more prone to oxidative insult than male smokers. In summary RS present in smoke induce mild lipid peroxidation but are not the major contributors of redox imbalance in smoke induced toxicity in the selected subjects.

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In our search to identify gene(s) involved in the rice self-defense responses, we cloned a novel rice (Oryza sativa L. cv. Nipponbare) gene, OsATX, a single copy gene, from the JA treated rice seedling leaves cDNA library. This gene encodes a 69 amino acid polypeptide with a predicted molecular mass of 7649.7 and a pI of 5.6. OsATX was responsive to cutting (wounding by cutting the excised leaf), over its weak constitutive expression in the healthy leaves. The critical signalling molecules, jasmonic acid (JA), salicylic acid (SA), abscisic acid (ABA), and hydrogen peroxide, together with protein phosphatase inhibitors, effectively up-regulated the OsATX expression with time, over the excised leaf cut control, whereas ethylene had no affect. Furthermore, copper, a heavy metal, also up-regulated OsATX expression. Moreover, induced expression of OsATX mRNA was influenced by light signal(s), and showed a requirement for de novo synthesized protein factors. Additionally, co-application of either JA or ABA with SA drastically suppressed the induced OsATX mRNA level. Finally, the blast pathogen, Magnaporthe grisea, triggered OsATX mRNA accumulation. These results strongly suggest a function/role(s) for OsATX in defense/stress responses in rice.

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Several new 3-arylaminomethyl-7H-6-(6-substituted-3-coumarino)-s-triazol o-[3,4-b] [1,3,4]thiadiazines were synthesized by condensing 3-arylaminomethyl-4-amino-5-mercapto-1,2,4-triazoles with 3-bromoacetyl-6-substituted coumarins in dioxan medium. The structures of newly synthesized compounds were established on the basis of analytical, NMR and mass spectral data. Some selected compounds from this series were subjected to antibacterial studies.

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Thymine and cytosine as well as the intermediates in pyrimidine biosynthetic pathway dihydroorotic acid, orotic acid, carbamyl aspartate and 5'-uridine monophosphate and folic acid, was synergistic. 2-14C-Thymine, 6-14C-orotic acid and 14C-formate but not 2-14C-uracil, were incorporated into DNA more in the presence of aflatoxin. These findings indicated that aflatoxin inhibited the pyrimidine base synthesis which could be overcome to a great extent by the addition of thymine and folic acid to aflatoxin-treated cells.

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