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Mohd Ishtikhar Tajjali Ilm Chandel Aamir Ahmad Mohd Sajid Ali Hamad A. Al-lohadan Ayman M. Atta Rizwan Hasan Khan 《PloS one》2015,10(9)
Quaternary amine of diethylaminoethyl rosin ester (QRMAE), chemically synthesized biocompatible rosin based cationic surfactant, has various biological applications including its use as a food product additive. In this study, we examined the amorphous aggregation behavior of mammalian serum albumins at pH 7.5, i.e., two units above their isoelectric points (pI ~5.5), and the roles played by positive charge and hydrophobicity of exogenously added rosin surfactant QRMAE. The study was carried out on five mammalian serum albumins, using various spectroscopic methods, dye binding assay, circular dichroism and electron microscopy. The thermodynamics of the binding of mammalian serum albumins to cationic rosin modified surfactant were established using isothermal titration calorimetry (ITC). It was observed that a suitable molar ratio of protein to QRMAE surfactant enthusiastically induces amorphous aggregate formation at a pH above two units of pI. Rosin surfactant QRMAE-albumins interactions revealed a unique interplay between the initial electrostatic and the subsequent hydrophobic interactions that play an important role towards the formation of hydrophobic interactions-driven amorphous aggregate. Amorphous aggregation of proteins is associated with varying diseases, from the formation of protein wine haze to the expansion of the eye lenses in cataract, during the expression and purification of recombinant proteins. This study can be used for the design of novel biomolecules or drugs with the ability to neutralize factor(s) responsible for the aggregate formation, in addition to various other industrial applications. 相似文献
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Biodiversity of Asian rice gall midge (Orseolia oryzae Wood Mason) from five countries examined by AFLP analysis. 总被引:8,自引:0,他引:8
S K Katiyar G Chandel Y Tan Y Zhang B Huang L Nugaliyadde K Fernando J S Bentur S Inthavong S Constantino J Bennett 《Génome》2000,43(2):322-332
Amplified fragment length polymorphism (AFLP) analysis was used to assess the biodiversity of one of the most important dipteran pests of cereals, the Asian rice gall midge (Orseolia oryzae Wood Mason). Larvae and pupae were collected at 15 locations in five Asian countries and preserved in 95% ethanol for storage, shipment, and DNA extraction using cetyltrimethylammonium bromide (CTAB). Although only approximately 1 microg of DNA was extracted from a single pupa or larva, the use of several AFLP primers in various combinations meant that this amount of DNA was sufficient to allow many DNA fingerprints to be made per individual. Fingerprints were sufficiently reproducible, especially during selective amplification, to allow the genetic diversity within a field population to be characterized. Extraction of DNA from a pool of 20 insects yielded AFLP fingerprints in which variation among individuals was sacrificed in favor of detecting differences among populations. For each location, pooled DNA was amplified with three primer pairs. A total of 261 distinct AFLP bands were identified for the 45 fingerprints. Cluster analysis, performed by the unweighted pair-group method (UPGMA), separated the populations into two distinct groups. Group I included two populations from Guangdong province of southern China and one each from Laos and Imphal in northeastern India, while group II was comprised of eleven populations from elsewhere in India (Assam, Orissa, Madhya Pradesh, Andhra Pradesh, and Kerala) and from Nepal and Sri Lanka. AFLP analysis provided insight into the origins of gall midge biotypes. In 1992, the prevailing biotype in Imphal changed from Indian biotype 3 to a new biotype 3M. Our data show that biotype 3M belongs to group I and did not arise by a recent mutation from biotype 3, which belongs to group II. By contrast, Indian biotypes 2 and 4 are likely to have diverged through recent mutation and selection, as are Chinese biotypes 1 and 4. The almost simultaneous emergence of new biotypes in Kerala and Sri Lanka during 1985-1988 was most probably coincidental, because these biotypes are not closely related. AFLP fingerprints were also able to detect sexual dimorphism in the DNA of adult gall midges and to distinguish gall midge from its major parasite Platygaster oryzae. 相似文献
35.
N Chandel B Sharma D Salhan M Husain A Malhotra S Buch PC Singhal 《American journal of physiology. Cell physiology》2012,303(6):C607-C615
Opiates have been reported to induce T cell loss. We evaluated the role of vitamin D receptor (VDR) and the activation of the renin-angiotensin system (RAS) in morphine-induced T cell loss. Morphine-treated human T cells displayed downregulation of VDR and the activation of the RAS. On the other hand, a VDR agonist (EB1089) enhanced T cell VDR expression both under basal and morphine-stimulated states. Since T cells with silenced VDR displayed the activation of the RAS, whereas activation of the VDR was associated with downregulation of the RAS, it appears that morphine-induced T cell RAS activation was dependent on the VDR status. Morphine enhanced reactive oxygen species (ROS) generation in a dose-dependent manner. Naltrexone (an opiate receptor antagonist) inhibited morphine-induced ROS generation and thus, suggested the role of opiate receptors in T cell ROS generation. The activation of VDR as well as blockade of ANG II (by losartan, an AT(1) receptor blocker) also inhibited morphine-induced T cell ROS generation. Morphine not only induced double-strand breaks (DSBs) in T cells but also attenuated DNA repair response, whereas activation of VDR not only inhibited morphine-induced DSBs but also enhanced DNA repair. Morphine promoted T cell apoptosis; however, this effect of morphine was inhibited by blockade of opiate receptors, activation of the VDR, and blockade of the RAS. These findings indicate that morphine-induced T cell apoptosis is mediated through ROS generation in response to morphine-induced downregulation of VDR and associated activation of the RAS. 相似文献
36.
Nitric oxide during ischemia attenuates oxidant stress and cell death during ischemia and reperfusion in cardiomyocytes 总被引:4,自引:1,他引:3
Iwase H Robin E Guzy RD Mungai PT Vanden Hoek TL Chandel NS Levraut J Schumacker PT 《Free radical biology & medicine》2007,43(4):590-599
Nitric oxide (NO) has been implicated as a cardioprotective agent during ischemia/reperfusion (I/R), but the mechanism of protection is unknown. Oxidant stress contributes to cell death in I/R, so we tested whether NO protects by attenuating oxidant stress. Cardiomyocytes and murine embryonic fibroblasts were administered NO (10-1200 nM) during simulated ischemia, and cell death was assessed during reperfusion without NO. In each case, NO abrogated cell death during reperfusion. Cells overexpressing endothelial NO synthase (NOS) exhibited a similar protection, which was abolished by the NOS inhibitor N(omega)-nitro-l-arginine methyl ester. Protection was not mediated by guanylate cyclase or the mitochondrial K(ATP) channel, as inhibitors of these systems failed to abolish protection. NO did not prevent decreases in mitochondrial potential, but cells protected with NO demonstrated recovery of potential at reperfusion. Measurements using C11-BODIPY reveal that NO attenuates lipid peroxidation during ischemia and reperfusion. Measurements of oxidant stress using the ratiometric redox sensor HSP-FRET demonstrate that NO attenuates protein oxidation during ischemia. These findings reveal that physiological levels of NO during ischemia can attenuate oxidant stress both during ischemia and during reperfusion. This response is associated with a remarkable attenuation of cell death, suggesting that ischemic cell death may be a regulated event. 相似文献
37.
Mark S Winterbone Mike J Sampson Shikha Saha Jackie C Hughes David A Hughes 《Cardiovascular diabetology》2007,6(1):1-6
Background
Little information is available on leptin concentrations in individuals with IGT. This study aims to determine and correlate leptin levels to anthropometric measures of obesity in pre-diabetic, (IFG and IGT), type 2 diabetic and normoglycaemic Saudis.Methods
308 adult Saudis (healthy controls n = 80; pre-diabetes n = 86; Type 2 diabetes n = 142) participated. Anthropometric parameters were measured and fasting blood samples taken. Serum insulin was analysed, using a solid phase enzyme amplified sensitivity immunoassay and also leptin concentrations, using radio-immunoassay. The remaining blood parameters were determined using standard laboratory procedures.Results
Leptin levels of diabetic and pre-diabetic men were higher than in normoglycaemic men (12.4 [3.2–72] vs 3.9 [0.8–20.0] ng/mL, (median [interquartile range], p = 0.0001). In females, leptin levels were significantly higher in pre-diabetic subjects (14.09 [2.8–44.4] ng/mL) than in normoglycaemic subjects (10.2 [0.25–34.8] ng/mL) (p = 0.046). After adjustment for BMI and gender, hip circumference was associated with log leptin (p = 0.006 with R2 = 0.086) among all subjects.Conclusion
Leptin is associated with measures of adiposity, hip circumference in particular, in the non-diabetic state among Saudi subjects. The higher leptin level among diabetics and pre-diabetics is not related to differences in anthropometric measures of obesity. 相似文献38.
39.
Shikha Verma Anamika Sharma Raj Kumar Charanjit Kaur Anju Arora Raghubir Shah Lata Nain 《Saudi Journal of Biological Sciences》2015,22(3):256-264
Nutrient management practices play a significant role in improving the nutritional quality of tomato. The present study deals with the evaluation of compost prepared using Effective Microorganisms (EM), on antioxidant and defense enzyme activities of Tomato (Lycopersicon esculentum). A field experiment with five treatments (control, chemical fertilizer and EM compost alone and in combination) was conducted in randomized block design. An increment of 31.83% in tomato yield was recorded with the combined use of EM compost and half recommended dose of chemical fertilizers (N50P30K25 + EM compost at the rate of 5 t ha−1). Similarly, fruit quality was improved in terms of lycopene content (35.52%), antioxidant activity (24–63%) and defense enzymes activity (11–54%), in tomatoes in this treatment as compared to the application of recommended dose of fertilizers. Soil microbiological parameters also exhibited an increase of 7–31% in the enzyme activities in this treatment. Significant correlation among fruit quality parameters with soil microbiological activities reveals the positive impact of EM compost which may be adopted as an eco-friendly strategy for production of high quality edible products. 相似文献
40.
Tanuja Rana Vanita Chandel Vipin Hallan Aijaz A. Zaidi 《Journal of plant biochemistry and biotechnology.》2011,20(1):138-141
Expression condition for maximum recovery of recombinant Apple chlorotic leaf spot virus (ACLSV) coat protein was standardized. The in vitro expressed fusion protein with 6xHis tag (~43 Kd) was purified from inclusion bodies and used as an antigen for raising polyclonal antiserum in rabbit. This antiserum consistently detected ACLSV in pome and stone fruits as well as herbaceous host plants by direct double antibody sandwich enzyme linked immunosorbent assay (DAS-ELISA) and direct tissue blot immunoassay (DTBIA). The conditions for immuno-capture RT-PCR (IC-RT-PCR) were also standardized. 相似文献