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991.
Hassan Imran Afridi Tasneem Gul Kazi Naveed Kazi Ghulam Abbas Kandhro Abdul Qadir Shah Jameel Ahmed Baig Sham Kumar Wadhwa Sumaira Khan Nida Fatima Kolachi Faheem Shah Mohammad Khan Jamali Mohammad Balal Arain 《Biological trace element research》2011,143(1):103-115
This study was designed to compare the levels of chromium (Cr) and manganese (Mn) in scalp hair, blood, and urine of night blindness in children age ranged (3–7) and (8–12) years of both genders, comparing them to sex- and age-matched controls. A microwave-assisted wet acid digestion procedure, was developed as a sample pretreatment, for the determination of Cr and Mn in biological samples of night blindness children. The proposed method was validated by using conventional wet digestion and certified reference samples of hair, blood and urine. The digests of all biological samples were analyzed for Cr and Mn by electrothermal atomic absorption spectrometry. The results indicated significantly higher levels of Cr, whilst low level of Mn in the biological samples (blood and scalp hair) of male and female night blindness children, compared with control subjects of both genders. These data present guidance to clinicians and other professional investigating deficiency of Mn and excessive level of Cr in biological samples (scalp hair and blood) of night blindness children. 相似文献
992.
Terry Yin Timothy E. Lindley Gregory W. Albert Raheel Ahmed Peter B. Schmeiser M. Sean Grady Matthew A. Howard Michael J. Welsh 《PloS one》2013,8(8)
Traumatic brain injury (TBI) is a common cause of morbidity and mortality in people of all ages. Following the acute mechanical insult, TBI evolves over the ensuing minutes and days. Understanding the secondary factors that contribute to TBI might suggest therapeutic strategies to reduce the long-term consequences of brain trauma. To assess secondary factors that contribute to TBI, we studied a lateral fluid percussion injury (FPI) model in mice. Following FPI, the brain cortex became acidic, consistent with data from humans following brain trauma. Administering HCO3− after FPI prevented the acidosis and reduced the extent of neurodegeneration. Because acidosis can activate acid sensing ion channels (ASICs), we also studied ASIC1a−/− mice and found reduced neurodegeneration after FPI. Both HCO3− administration and loss of ASIC1a also reduced functional deficits caused by FPI. These results suggest that FPI induces cerebral acidosis that activates ASIC channels and contributes to secondary injury in TBI. They also suggest a therapeutic strategy to attenuate the adverse consequences of TBI. 相似文献
993.
Davide Danovi Amos Folarin Sabine Gogolok Christine Ender Ahmed M. O. Elbatsh P?r G. Engstr?m Stefan H. Stricker Sladjana Gagrica Ana Georgian Ding Yu Kin Pong U Kevin J. Harvey Patrizia Ferretti Patrick J. Paddison Jane E. Preston N. Joan Abbott Paul Bertone Austin Smith Steven M. Pollard 《PloS one》2013,8(10)
Glioblastoma multiforme (GBM) is the most common primary brain cancer in adults and there are few effective treatments. GBMs contain cells with molecular and cellular characteristics of neural stem cells that drive tumour growth. Here we compare responses of human glioblastoma-derived neural stem (GNS) cells and genetically normal neural stem (NS) cells to a panel of 160 small molecule kinase inhibitors. We used live-cell imaging and high content image analysis tools and identified JNJ-10198409 (J101) as an agent that induces mitotic arrest at prometaphase in GNS cells but not NS cells. Antibody microarrays and kinase profiling suggested that J101 responses are triggered by suppression of the active phosphorylated form of polo-like kinase 1 (Plk1) (phospho T210), with resultant spindle defects and arrest at prometaphase. We found that potent and specific Plk1 inhibitors already in clinical development (BI 2536, BI 6727 and GSK 461364) phenocopied J101 and were selective against GNS cells. Using a porcine brain endothelial cell blood-brain barrier model we also observed that these compounds exhibited greater blood-brain barrier permeability in vitro than J101. Our analysis of mouse mutant NS cells (INK4a/ARF−/−, or p53−/−), as well as the acute genetic deletion of p53 from a conditional p53 floxed NS cell line, suggests that the sensitivity of GNS cells to BI 2536 or J101 may be explained by the lack of a p53-mediated compensatory pathway. Together these data indicate that GBM stem cells are acutely susceptible to proliferative disruption by Plk1 inhibitors and that such agents may have immediate therapeutic value. 相似文献
994.
This work aims at preparation and characterization of novel synthesized nanocomposites based on polystyrene (Psty) packaging material waste. Moreover, the antimicrobial and antioxidant properties were examined and evaluated. The Psty was grafted with two different monomers such as acrylic and maleic acids (AAc and MAc, respectively) in presence of montmorillonite (MMT) using potassium persulfate as initiator under nitrogen atmosphere. The prepared nanocomposites were characterized using Fourier transform infrared spectroscopy (FT-IR), transmission (TEM) and scanning electron microscopes (SEM). Moreover, the antimicrobial activity was evaluated using agar disc diffusion method against gram negative bacteria such as: Klebsiella pneumonia, and Escherichia coli and gram positive bacterium (Sarcina lutea); in addition to the yeast fungus (Candida albicans). Furthermore, the radical scavenging ability of the prepared nanocomposites has been examined using the DPPH assay. 相似文献
995.
M. Khawar Rauf Imtiaz-ud-Din Amin Badshah Marcel Gielen Masahiro Ebihara Dick de Vos Safeer Ahmed 《Journal of inorganic biochemistry》2009,103(8):1135-1144
A series of copper(I) complexes of N,N′-disubstituted thioureas, [C6H5CONHCSNHR]Cu(I)Cl where R = C6H5 (1a), 2-ClC6H4 (2a), 3-ClC6H4 (3a), 4-ClC6H4 (4a), 2,3-Cl2C6H3 (5a), 2,4-Cl2C6H3 (6a), 2,5-Cl2C6H3 (7a), 2,6-Cl2C6H3 (8a), 3,4-Cl2C6H3 (9a) and 3,5-Cl2C6H3 (10a) have been synthesized. These complexes (1a–10a) have been characterized by elemental analyses, IR, 1H and 13C NMR spectroscopy, cyclic voltammetry and single crystal XRD for 1a and 8a, and for ligand 7. The X-ray crystal structures reveal that the complexes 1a and 8a are mononuclear in the solid state in which the copper atoms adopt a distorted tetrahedral geometry. In both the cases, the neutral N,N′-disubstituted thiourea ligands have been coordinated to the Cu(I) through the sulphur atom in a terminal mode. The complexes have been screened for their in vitro cytotoxic activity in human cell lines carcinomas A498 (Renal), EVSA-T (Breast), H226 (Lung), IGROV (Ovarian), M19 (Melanoma-Skin), MCF-7 (Breast) and WIDR (Colon). They show a moderate cytotoxicity against these seven human cancer cell lines comparable to that of the less active standard chemotherapeutic drugs used for comparison. They were also screened for their anti-bacterial activity and were found less active than the standard drug Imipenem. 相似文献
996.
Mousa HM Omer OH Ali BH Al-Wabel N Ahmed SM 《Journal of physiology and biochemistry》2006,62(3):213-218
In this study, we measured the concentration of some antioxidant substances in erythrocytes hemolysate, liver, kidney and brain in young and adult camels. It has been found that the activity of the antioxidant enzymes glutathione peroxidase (GSH-Px), catalase (CAT), superoxide dismutase (SOD) and the concentration of glutathione, ascorbic acid and alpha-tocopherol are high in both young and adult camels. GSH-Px and CAT activities were higher in adult camels than in the young whereas no significant difference in the activity of SOD between young and adult camels was noticed. Glutathione was present in all tissues studied. Ascorbic acid was found to have significantly higher values in young camels. From this study it could be concluded that, as in other mammals, camel tissues contain a powerful antioxidant system. The liver has the highest contents of antioxidants and antioxidant enzymes indicating that it plays an important role in pro-oxidants detoxification. Age has a variable effect on the antioxidant system in camels. 相似文献
997.
Alexandra Vanessa Finsen Thor Ueland Ivar Sjaastad Trine Ranheim Mohammed S. Ahmed Christen P. Dahl Erik T. Askevold Svend Aakhus Cathrine Husberg Arnt E. Fiane Martin Lipp Lars Gullestad Geir Christensen P?l Aukrust Arne Yndestad 《PloS one》2014,9(11)
Background
CCL21 acting through CCR7, is termed a homeostatic chemokine. Based on its role in concerting immunological responses and its proposed involvement in tissue remodeling, we hypothesized that this chemokine could play a role in myocardial remodeling during left ventricular (LV) pressure overload.Methods and Results
Our main findings were: (i) Serum levels of CCL21 were markedly raised in patients with symptomatic aortic stenosis (AS, n = 136) as compared with healthy controls (n = 20). (ii) A CCL21 level in the highest tertile was independently associated with all-cause mortality in these patients. (iii) Immunostaining suggested the presence of CCR7 on macrophages, endothelial cells and fibroblasts within calcified human aortic valves. (iv). Mice exposed to LV pressure overload showed enhanced myocardial expression of CCL21 and CCR7 mRNA, and increased CCL21 protein levels. (v) CCR7−/− mice subjected to three weeks of LV pressure overload had similar heart weights compared to wild type mice, but increased LV dilatation and reduced wall thickness.Conclusions
Our studies, combining experiments in clinical and experimental LV pressure overload, suggest that CCL21/CCR7 interactions might be involved in the response to pressure overload secondary to AS. 相似文献998.
Prevalence and Risk Factors of Helicobacter pylori Infection in Saudi Children: A Three‐Year Prospective Controlled Study 下载免费PDF全文
999.
Thein M Cheng A Khanna P Zhang C Park EJ Ahmed D Goodrich CJ Asphahani F Wu F Smith NB Dong C Jiang X Zhang M Xu J 《Biosensors & bioelectronics》2011,27(1):25-33
We developed a new instrumental method by which human melanoma cells (LU1205) are sonoporated via radiation pressures exerted by highly-confined ultrasonic waves produced by high lateral-resolution ultrasonic micro-transducer arrays (UMTAs). The method enables cellular-level site-specific sonoporation within the cell monolayer due to UMTAs and can be applicable in the delivery of drugs and gene products in cellular assays. In this method, cells are seeded on the biochip that employs UMTAs for high spatial resolution and specificity. UMTAs are driven by 30-MHz sinusoidal signals and the resulting radiation pressures induce sonoporation in the targeted cells. The sonoporation degree and the effective lateral resolution of UMTAs are determined by performing fluorescent microscopy and analysis of carboxylic-acid-derivatized CdSe/ZnS quantum dots passively transported into the cells. Models representing the transducer-generated ultrasound radiation pressure, the ultrasound-inflicted cell membrane wound, and the transmembrane transport through the wound are developed to determine the ultrasound-pressure-dependent wound size and enhanced cellular uptake of nanoparticles. Model-based calculations show that the effective wound size and cellular uptake of nanoparticles increase linearly with increasing ultrasound pressure (i.e., at applied radiation pressures of 0.21, 0.29, and 0.40 MPa, the ultrasound-induced initial effective wound radii are 150, 460, and 650 nm, respectively, and the post-sonoporation intracellular quantum-dot concentrations are 7.8, 22.8, and 29.9 nM, respectively) and the threshold pressure required to induce sonoporation in LU1205 cells is ~0.12 MPa. 相似文献
1000.
Comuzzie AG Tejero ME Funahashi T Martin LJ Kissebah A Takahashi M Kihara S Tanaka S Rainwater DL Matsuzawa Y MacCluer JW Blangero J 《Human biology; an international record of research》2007,79(2):191-200
Results from previous studies suggest that adiponectin levels are associated with risk factors for cardiovascular disease and type 2 diabetes mellitus; however, the genetic and/or environmental components of this relationship have not been characterized. The aims of this study were (1) to assess the presence of pleiotropy between adiponectin levels and risk factors for cardiovascular disease and (2) to study the association of circulating levels of adiponectin with risk factors for cardiovascular disease in the absence and presence of obesity in Mexican American adults from the San Antonio Family Heart Study. Body composition and circulating levels of adiponectin, leptin, and lipid subfractions and measurements of glucose metabolism were measured in 898 subjects. The mean and standard error of the circulating levels of adiponectin was 8.7 +/- 3.2 microg/ml. Bivariate quantitative analyses between adiponectin levels and phenotypes related to cardiovascular disease and type 2 diabetes mellitus were conducted using the variance decomposition approach implemented in SOLAR. A second analysis in unrelated subjects compared these risk factors between sex- and age-matched lean and obese subjects with high and low adiponectin levels. We found significant evidence of pleiotropy (i.e., shared genetic effects) between plasma levels of adiponectin and well-established risk factors for cardiovascular disease and type 2 diabetes mellitus. Individuals with low adiponectin levels per body weight had more adverse risk profiles. These findings offer new insights into the genetic connection between increasing adiposity and risk for cardiovascular disease and type 2 diabetes mellitus, and they suggest that adiponectin may be an important risk factor for the development of these conditions. 相似文献