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31.
Exposure of aqueous solutions of native human choriogonadotropin (hCG), asialo-hCG (A-hCG), and chemically deglycosylated hCG (DG-hCG) to heat treatment revealed significant differences in their stability. Solutions of hCG and A-hCG were rapidly inactivated above 50 degrees C. On the other hand, solutions of DG-hCG were comparatively more stable under similar conditions as shown by the retention of significant receptor binding, immunological, and hormonal antagonistic activities. Heated solutions (100 degrees C) of hCG and A-hCG quickly lost their ability to enhance the fluorescence of the probe 1-anilino-8-naphthalenesulfonate (1,8-ANS) indicating dissociation into subunits. DG-hCG solutions were more stable in this respect suggesting significant preservation of conformational features required for the interaction with 1,8-ANS. Solutions of hCG and A-hCG which had been thermally denatured (100 degrees C, 10 min) required almost 48 h at 37 degrees C to regain complete ANS binding ability as well as receptor binding activity. Under the same conditions, heated solutions of DG-hCG completely regained these abilities in less than 2 h. A similar pattern was observed with acid (pH 2.0)-dissociated hCG, A-hCG, and DG-hCG. While heated solutions of hCG had no effect on the action of native hCG in vitro, heated DG-hCG solutions still retained their ability to antagonize the cyclic AMP accumulation or steroidogenesis induced by native hCG in rat interstitial cells. Thus, removal of carbohydrate residues (approximately 75% loss) from hCG renders the hormone more resistant to thermal denaturation. 相似文献
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The effects of urea and glycine-betaine (GB) osmolytes on the hydrophobic interactions of neopentane in water have been studied using molecular dynamics simulations. From the study of the potentials of mean force, it is observed that both urea and GB decrease the association and solvation of neopentane. The calculated equilibrium constants show that urea and GB decrease the population of solvent-separated minima of neopentane. The hydrophobic association as well as solvation of neopentane molecules are stabilised by entropy and enthalpy in the mixtures. The radial distribution functions (RDFs) and running coordination numbers of water, urea and GB molecules show that neopentane shows salting-in behaviour in aqueous-GB, aqueous-urea and aqueous-urea-GB mixtures. Neopentane is preferentially solvated by GB in aqueous-GB and preferentially solvated by urea in aqueous-urea-GB solutions. The preferential solvation of neopentane by GB suggests that GB decreases the interaction between neopentane molecules i.e. salting-in of neopentane. The calculated solvation free energies and radial density profiles of neopentane also support the salting-in behaviour of neopentane in the mixtures of these osmolytes. 相似文献
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Basavegowdanadoddi Marinaik Chandranaik Sonnahallipura Munivenkatappa Byregowda Mudalagiri Dasappagupta Venkatesha Kantharajapura Ramanna Ramesha Poojappa Nandini Poorvi Reddy Thushara Bindu KV Beechagondahalli Papanna Shivashankar Byadarahalli Puttaswamy Shankar Methuku Sobha Rani 《European Journal of Wildlife Research》2018,64(1):4
We report the molecular epidemiology of highly pathogenic avian influenza (HPAI) virus involved in an outbreak causing death in free-ranging wild birds at Mysore, Karnataka state of India. The virus was typed as HPAI A(H5N8) by conventional and TaqMan probe based real-time PCR assays. Six isolates of HPAI virus were recovered in 9-day-old embryonated chicken eggs. Haemagglutinin gene-based phylogeny of virus isolates showed >?99.9% nucleotide sequence identity with HPAI A(H5N8) isolates from migratory birds and domestic poultry from China and Korea indicating either these wild birds have routed their migration through Korea and/or eastern China or these dead birds must have directly or indirectly contacted with wild birds migrating from Eastern China and/or Korean regions. The study emphasises the role of migratory wild birds in spread of HPAI across the globe. 相似文献
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L. Nivethitha A. Mooventhan N. K. Manjunath Lokesh Bathala Vijay K. Sharma 《Applied psychophysiology and biofeedback》2018,43(1):87-92
Various pranayama techniques are known to produce different physiological effects. We evaluated the effect of three-different pranayama techniques on cerebrovascular hemodynamics. Eighteen healthy volunteers with the mean?±?standard deviation age of 23.78?±?2.96 years were performed three-different pranayama techniques: (1) Bhramari, (2) Kapalbhati and (3) Bahir-Kumbhaka in three-different orders. Continuous transcranial Doppler (TCD) monitoring was performed before, during and after the pranayama techniques. TCD parameters such as peak systolic velocity, end diastolic velocity (EDV), mean flow velocity (MFV) and pulsatility index (PI) of right middle cerebral artery were recorded. Practice of Kapalbhati showed significant reductions in EDV and MFV with significant increase in PI while, Bahir-Kumbhaka showed significant increase in EDV and MFV with significant reduction in PI. However, no such significant changes were observed in Bhramari pranayama. Various types of pranayama techniques produce different cerebrovascular hemodynamic changes in healthy volunteers. 相似文献
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A. Desai K. Murali-Krishna B. Ramireddy V. Ravi R. Manjunath 《Journal of biosciences》1997,22(1):33-45
Japanese encephalitis virus (JEV) is a positive stranded RNA virus that belongs to the flavivirus group. JEV infection damages
the central nervous system (CNS) and is one of the main causative agents of acute encephalitis. H-2 restricted virus-specific
cytotoxic T lymphocytes (CTL) have been generated specifically against JEV in our laboratory and these CTL have been shown
to protect mice against lethal challenge with JEV. Virus replication was found to be inhibited in the brains of animals that
were adoptively transferred with JEV specific CTL as revealed by immunohistological staining as well as viral plaque assays.
We further show that virus specific CTL could be recovered from such protected mice as long as 45 days after adoptive transfer. 相似文献
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