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161.
Impact of Cattaneo-Christov Heat Flux in Jeffrey Fluid Flow with Homogeneous-Heterogeneous Reactions
Two-dimensional stretched flow of Jeffrey fluid in view of Cattaneo-Christov heat flux is addressed. Effects of homogeneous-heterogeneous reactions are also considered. Suitable transformations are used to form ordinary differential equations. Convergent series solutions are computed. Impact of significant parameters on the velocity, temperature, concentration and skin friction coefficient is addressed. Analysis of thermal relaxation is made. The obtained results show that ratio of relaxation to retardation times and Deborah number have inverse relation for velocity profile. Temperature distribution has decreasing behavior for Prandtl number and thermal relaxation time. Also concentration decreases for larger values of strength of homogeneous reaction parameter while it increases for strength of heterogeneous reaction parameter. 相似文献
162.
Hassan Imran Afridi Tasneem Gul Kazi Naveed Kazi Ghulam Abbas Kandhro Jameel Ahmed Baig Mohammad Khan Jamali Mohammad Balal Arain Abdul Qadir Shah Faheem Shah Sumaira Khan Nida Fatima Kolachi 《Biological trace element research》2011,141(1-3):26-40
The exposure of toxic elements may directly or indirectly associate with different pathogenesis of heart diseases. In the present study, the association of arsenic (As), cadmium (Cd), cobalt (Co), lead (Pb), and nickel (Ni) in biological samples (whole blood and urine) and mortality from myocardial infarction (MI) patients at first, second, and third heart attacks was carried out. Both biological samples of 130 MI patients (77 male and 53 female), with ages ranging from 45 to 60?years, and 61 healthy persons (33 male and 28 female) of the same age group were collected. The elements in biological samples were assessed by electrothermal atomic absorption spectrophotometer, prior to microwave-assisted acid digestion. The validity of methodology was checked by the biological certified reference materials. During this study, 78% of 32 patients aged above 50?years, registered after third MI attack, died. In these subjects, the levels of As, Cd, Co, Ni, and Pb in blood samples were higher in MI patients as compared with referents (p?<?0.05), while increased by 11.7%, 12.2%, 5.55%, and 7.2%, respectively, in the blood samples of those patients who tolerated the third MI attack (p?=?0.12). The high level of understudied toxic elements may play a role in the mortality of MI patients. 相似文献
163.
164.
Kolachi NF Kazi TG Afridi HI Kazi N Khan S Kandhro GA Shah AQ Baig JA Wadhwa SK Shah F Jamali MK Arain MB 《Biological trace element research》2011,143(1):196-212
The mechanism of transport of trace elements from the mother to the newborn is still not well known. The aim of present study was to compare the status of trace toxic elements, arsenic (As), cadmium (Cd), and lead (Pb) in biological samples (whole blood, urine and scalp hair) of insulin-dependent diabetic mothers (age ranged 30-40) and their newly born infants (n = 76). An age and socioeconomics matched 68 nondiabetic mothers and their infants, residing in the same locality, who were selected as referents. The elemental concentrations in all three biological samples were determined by an electrothermal atomic absorption spectrometer, prior to microwave-assisted acid digestion. The mean values of As, Cd, and Pb in all biological samples of diabetic mothers and their infants were significantly higher as compared to the referent mother-infant pair samples (p < 0.01). The high levels of As, Cd, and Pb in biological samples of diabetic women may play a role in the pathogenesis of diabetes mellitus and impacts on their neonates. 相似文献
165.
166.
Shahzina Kanwal Yann Fardini Patrick Pagesy Thierry N’Tumba-Byn Cécile Pierre-Eugène Elodie Masson Cornelia Hampe Tarik Issad 《PloS one》2013,8(7)
O-GlcNAcylation (addition of N-acetyl-glucosamine on serine or threonine
residues) is a post-translational modification that regulates stability,
activity or localization of cytosolic and nuclear proteins. O-linked
N-acetylgluocosmaine transferase (OGT) uses UDP-GlcNAc, produced in the
hexosamine biosynthetic pathway to O-GlcNacylate proteins. Removal of O-GlcNAc
from proteins is catalyzed by the β-N-Acetylglucosaminidase (OGA). Recent
evidences suggest that O-GlcNAcylation may affect the growth of cancer cells.
However, the consequences of O-GlcNAcylation on anti-cancer therapy have not
been evaluated. In this work, we studied the effects of O-GlcNAcylation on
tamoxifen-induced cell death in the breast cancer-derived MCF-7 cells.
Treatments that increase O-GlcNAcylation (PUGNAc and/or glucosoamine) protected
MCF-7 cells from death induced by tamoxifen. In contrast, inhibition of OGT
expression by siRNA potentiated the effect of tamoxifen on cell death. Since the
PI-3 kinase/Akt pathway is a major regulator of cell survival, we used BRET to
evaluate the effect of PUGNAc+glucosamine on PIP3 production. We
observed that these treatments stimulated PIP3 production in MCF-7
cells. This effect was associated with an increase in Akt phosphorylation.
However, the PI-3 kinase inhibitor , which abolished the effect of
PUGNAc+glucosamine on Akt phosphorylation, did not impair the protective effects
of PUGNAc+glucosamine against tamoxifen-induced cell death. These results
suggest that the protective effects of O-GlcNAcylation are independent of the
PI-3 kinase/Akt pathway. As tamoxifen sensitivity depends on the estrogen
receptor (ERα) expression level, we evaluated the effect of PUGNAc+glucosamine
on the expression of this receptor. We observed that O-GlcNAcylation-inducing
treatment significantly reduced the expression of ERα mRNA and protein,
suggesting a potential mechanism for the decreased tamoxifen sensitivity induced
by these treatments. Therefore, our results suggest that inhibition of
O-GlcNAcylation may constitute an interesting approach to improve the
sensitivity of breast cancer to anti-estrogen therapy. LY294002相似文献
167.
168.
Ravi Datta Sharma Rajnee Kanwal Andrew M. Lynn Prerna Singh Syed Tazeen Pasha Tasneem Fatma Safdar Jawaid 《Journal of molecular modeling》2013,19(9):3993-4002
Heme containing proteins are associated with peroxidase activity. The proteins like hemoglobin, myoglobins, cytochrome c and micro-peroxidase other than peroxidases have been shown to exhibit weak peroxidase-like activity. This weak peroxidase–like activity in hemoglobin-like molecules is due to heme moiety. We conducted molecular dynamics (MD) studies to decipher the unfolding path of Ba-Glb (a truncated hemoglobin from Bacillus anthracis) and the role of heme moiety to its unfolding path. The similar unfolding path is also observed in vitro by UV/VIS spectroscopy. The data confirmed that the unfolding of Ba-Glb follows a three state process with a meta-stable (intermediate) state between the native and unfolded conformations. The present study is supported by several unfolding parameters like root-mean-square-deviation (RMSD), dictionary of protein secondary structure (DSSP), and free energy landscape. Understanding the structure of hemoglobin like proteins in unicellular dreaded pathogens like B. anthracis will pave way for newer drug discovery targets and in the disease management of anthrax. 相似文献
169.
Kanwal Harpreet Kaur Reddy M. Sudhakara 《World journal of microbiology & biotechnology》2011,27(3):687-691
The effect of different carbon, nitrogen sources and inducers on growth and ligninolytic activity by Morel mushroom Morchella crassipes was investigated. The maximum growth was observed in mineral salts broth containing glucose as the carbon source and sodium
nitrate as the nitrogen source. Among the inducers, chemical inducers inhibited the growth whereas in natural substrates,
growth was not affected much. Manganese peroxidase and lignin peroxidase activity were not detected in the medium with different
carbon and nitrogen sources, whereas laccase activity varied depending on carbon source (0.7–3.48 U/ml). Among the inducers,
natural inducers resulted in an increase in the enzyme activities. Maximum laccase activity was observed in rice straw (12.
6 U/ml) followed by ABTS (11.6 U/ml); Manganese peroxidase activity was maximum in rice straw (14.32 U/l) wheat straw (12.16 U/l)
and phenol red (15 U/l) as the inducers, whereas for Lignin peroxidase activity, rice straw (22 U/l), wheat straw (16 U/l)
and veratrylalcohol (20 U/l) served as the best inducers. 相似文献
170.
Nida F. Kolachi Tasneem G. Kazi Hassan I. Afridi Naveed G. Kazi Moeena A. Mughal Sumaira Khan 《Biological trace element research》2013,151(2):187-194
The use of natural remedies and pharmacological mineral supplements for liver disease treatment has a long history. In present study, the levels of selenium (Se) and zinc (Zn) were determined in biological samples (serum and whole blood) of female hepatitis C patients (n?=?132), age ranged 30–45 years, before and after 30 days treatment with herbal/pharmaceutical supplements. For comparative study, 128 age-matched female subjects, residing in the same residential areas and have socioeconomic status, were selected as referents. The Se and Zn in supplements, blood, and sera were determined by atomic absorption spectrometry. It was observed that Zn and Se in blood and serum samples of viral hepatitis C (HCV) patients were reduced in the range of 28.6–39 % and 24–36 %, respectively, as compared to those of referents. After herbal/pharmaceutical supplementations, 20.6–25.0 and 9.15–13.2 % of Zn and 10.6–12.1 and 19.6–21.4 % of Se were enhanced in sera and blood samples of HCV patients, respectively. The resulted data indicated that the levels of Se and Zn in addition to some biochemical parameters were improved in HCV patients after herbal/pharmaceutical supplementation. The effects of both supplements were not significantly different (p?>?0.05). 相似文献