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Chromium is an important alloying element of stainless steel (SS) and SS is the main constituent of structural material proposed for fusion reactors. Energy and double differential cross section data will be required to estimate nuclear responses in the materials used in fusion reactors. There are no experimental data of energy and double differential cross section, available for neutron induced reactions on natural chromium at 14 MeV neutron energy. In this study, energy and double differential cross section data of (n,p) and (n,α) reactions for all the stable isotopes of chromium have been estimated, using appropriate nuclear models in TALYS code. The cross section data of stable isotopes are later converted into the energy and double differential cross section data of natural Cr using the isotopic abundance. The contribution from compound, pre-equilibrium and direct nuclear reaction to total reaction have also been calculated for Cr(n,p) and Cr(n,α). The calculation of energy differential cross section shows that most of emitted protons and alpha particles are of 3 and 8 MeV respectively. The calculated data is compared with the data from EXFOR data library and is found to be in good agreement. [ABSTRACT FROM AUTHOR]

Background: Efflux pump mediated antibiotic resistance is an unnoticed and undetected mechanism in clinical microbiology laboratory. RND efflux systems are known for aminoglycoside and tetracycline resistance whereas their role in carbapenem non-susceptibility is not established. The study was undertaken to investigate the role of efflux pump in providing resistance against carbapenems and their response against concentration gradient carbapenem stress on the transcriptional level of the AcrAB gene in the clinical isolates of Escherichia coli from a tertiary referral hospital of Northeast India., Results: Out of 298 non-susceptible Escherichia coli isolates 98 isolates were found to have efflux pump mediated carbapenem non-susceptibility. Among them thirty-five were non carbapenemase producers and their expressional levels were verified using qRT-PCR under concentration gradient carbapenem stress. In this study, a strong correlation between ertapenem resistance and AcrA overexpression was observed which has not been reported previously. Further, it was observed that imipenem stress increased AcrB expression in Escherichia coli which holds the novelty of this study. Additionally, the transcription of AcrR was insistently increased which is much higher than the transcriptional level of AcrA under concentration gradient carbapenem stress condition., Conclusion: The study established that AcrAB pump is a relevant antibiotic resistance determinant in bacterial pathogen, has an important role in developing resistance against carbapenem group of antibiotics.

A Ru(II)-catalyzed regioselective C-H activation toward hydroxymethylation of β-carbolines and isoquinolines as effective directing groups has been developed, and the mechanism was probed by using online electrospray ionization-tandem mass spectrometry. The introduction of the hydroxymethyl group in the biologically relevant molecules routed via C-H functionalization remains an important task. Gratifyingly, this protocol draws attention to the regioselective formation of monohydroxymethylated β-carboline/isoquinoline products exclusively.

In the current study, a dimeric phenoloxidase (PO) from the hemolymph of healthy and diseased (pebrine infected) larvae of Antheraea assamensis Helfer was extracted and purified. The protein was subjected to purification using Sephacryl S-100 and CM Sepharose chromatography. The enzyme comprised of two subunits of ~76.8 and 76 kDa that showed PO activity in 6 mM l-3,4-dihydroxyphenylalanine (L-DOPA) and 8 mM catechol but not in hydroquinone. Optimum temperature for PO activity was 30°C in l-DOPA and 37°C in catechol. Optimum pH ranged from 6.8 to 7.0 in L-DOPA and 7.0-7.2 in catechol. Specific activity of the purified PO from healthy larvae was 53.9 µM/min per mg of protein per ml in L-DOPA and 50.77 µM/min per mg of protein per ml in catechol. Specific activity of PO from diseased larvae was 30.0 µM/min per mg of protein per ml in L-DOPA and 28.55 µM/min per mg of protein per ml in catechol. Purification fold was 3.27-4.21 for healthy and 2.38-2.56 for diseased fractions. The enzyme showed the Michaelis constant (K m ) of 2.46-2.85 mM for healthy and diseased fractions in L-DOPA. In catechol K m of 9.23-17.71 mM was observed. Peptidoglycan was the best activator of purified PO from both healthy and diseased fractions. Interactions between controls and activators appeared statistically significant (F = 767.5; df = 3; P < 0.0001). Na + , K + , and Cu 2+ increased, whereas Ca 2+ , Zn 2+ , Mg 2+ , and Co 2+ decreased PO activity. The overall interactions appeared highly significant (F = 217.0; df = 27; P < 0.0001). Kojic acid, dithiothreitol, thiourea, phenylthiourea, carbendazim, N-bromosuccinimide, N,N,N',N'-tetraacetic acid, and diethyldithiocarbamate inhibited PO activity., (© 2018 Wiley Periodicals, Inc.)

Rotavirus (RV) has been considered as one of the most important cause of severe gastroenteritis among human infants and the neonates of most farm animal species worldwide. The present study was undertaken to detect rotavirus from faecal samples of bovine calves and to investigate genotypic distribution of rotavirus among bovine population during the period from June 2014 to May 2015. A total of 196 faecal samples were collected from both diarrhoeic and non-diarrhoeic calves with age group up to 4 months from different places of Assam, India. Screening of the 196 samples by RNA-PAGE revealed 26 (13.26%) to be positive for bovine RV with characteristic migration pattern of group A RV. The same number samples screened by RT-PCR revealed 71 (36.22%) to be positive for both VP7 and VP4 genes of group A bovine RV. RT-PCR was found to be more sensitive than RNA-PAGE. All non-diarrhoeic samples were negative for RV. Genotyping of RV was carried out by nested-multiplex PCR using type-specific primers of common genotypes. Study revealed that, the most common genotype circulating among bovine population of Assam is G10P[11]. Of 71 RV positive samples, 24 (33.80%) samples were found to be typeable for G10P[11] RV genotype while rest 47 samples were either non-typeable or mixed type. [ABSTRACT FROM AUTHOR]

Citrus plants belonging to the family Rutaceae, are traditionally used by the local people India to treat scurvy, rheumatism, stomachic, diarrhea, liver disorders and used as an antioxidant. They are valuable source of phenolic and other biologically active compounds. Phenolic compounds have been reported to have multiple biological effects. In this paper quantitative determination of phenols and flavonoids of Citrus limon L Burmf leaves extracts was carried out using spectrophotometric methods. The plant material was collected from Assam, north eastern region of India. Total phenolic content was determined by Folin-Ciocalteu method and aluminium chloride method was used for flavonoid determination. Acetone and methanol extracts of leaves showed quite high amount of phenol as well as flavinoid contents compared to ethanol and ethyl acetate extracts. However, all the extracts exhibited significant results. [ABSTRACT FROM AUTHOR]

Classical swine fever virus ( CSFV) is the causative agent of a highly contagious disease, hog cholera in pigs. The disease is endemic in many parts of the world and vaccination is the only way to protect the animals from CSFV infection. Wild hogs belong to the species Sus Scrofa Cristatus under the family Suidae are quite susceptible to CSFV infection. The epidemiological role concerning classical swine fever ( CSF) in India is largely unknown. We report here the three isolated cases of CSF in wild hogs from three National parks, namely Kaziranga National Park, Manas National Park and Jaldapara National Park, from north-east part of India. The post-mortem and histopathological findings were clearly indicative for CSFV infection. The presence of CSFV genome was demonstrated in several organs and tissues collected from hogs died due to viral infection. In addition, CSF-specific antibodies were detected in two wild hogs as well as in eighteen feral pigs from the same locations. The phylogenetic analysis of the partial E2 protein gene and 5′ untranslated region of CSFV isolates from the wild hog showed identities with genotype 2.2 of the Indian isolates. Occurrence of CSF in wild hogs may pose a potent threat in the epidemiology of the virus in Northeast part of India. To the best of our knowledge, the report presented in the manuscript is the first comprehensive report on CSF in wild hogs form Northeast India. The findings reported would help us to understand the epidemiology and biology of CSFV in wild animals. [ABSTRACT FROM AUTHOR]

Abstract Previous studies have shown that the circadian system of Japanese quail is composed of multiple photic inputs and multiple oscillators. Among these are extraretinal photoreceptors that mediate both circadian and photoperiodic responses and circadian pacemakers in the eyes that, via neural and hormonal outputs, help to maintain rhythmicity of central circadian clocks (presumably located in the suprachiasmatic area of the hypothalamus). Furthermore, a component of the central circadian system is influenced by reproductive hormones. Under certain conditions, the circadian system of female quaff can be induced to split into two circadian components: one driven by ocular pacemakers and one driven by feedback from reproductive hormones. Importantly, ovulation is either inhibited or permitted as these two oscillators (or sets of oscillators) constantly change internal phase relationships with each other, suggesting an "internal coincidence" mechanism in the control of ovulation. The oviposition patterns of quaff in light-dark (LD) cycles also support an internal coincidence mechanism. The authors tested the hypothesis that the ocular pacemakers are an important component of an internal coincidence mechanism controlling ovulation by examining the effects of blinding by complete eye removal (EX), and the effects of eye-patching, on the body temperature and oviposition patterns of quail exposed to 24-h LD cycles. They also examined the effects of EX on quaff exposed to continuous light (LL) and to continuous darkness (DD). Neither EX nor eyepatching affected the oviposition patterns of birds in LD. Furthermore, robust body temperature and oviposition rhythms continued in EX birds in LL, but body temperature became arrhythmic in DD with the cessation of ovulation. The results do not show a role for ocular pacemakers in the control of ovulation, but they do support the hypotheses that (1) entrainment of the central oscillators by extraretinally perceived light is s... [ABSTRACT FROM AUTHOR]