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81.
Life-tables of the Daphnia species (D. longispina and D. obtusa), currently inhabiting the previously acidified Lake Orta,
were followed to study the side effects of liming on the demographic parameters (e.g. longevity, body size increment, eggs
and new-borns production), of both species. Different media were prepared to simulate the lake water pH's (5, 6 and 7), and
copper concentrations (40 μg l-1), before and after liming, using GF/C filtered lake water in such simulation and as a reference medium. The obtained results
have shown that, the individuals of D. longispina were only able to survive after the liming and the consequent reduction
in copper concentrations. However, due to shift occurred in the different media pH's after liming toward slightly alkaline
conditions, no significant variations in body size increment or in eggs and newborns production were detected of this species
in the different media (p = 0.38, p = 0.29, p = 0.09 respectively). On the other hand, the effect of the variations in pH
on the body size increment of the B. obtusa individuals was marginally significant (p = 0.07). A highly significant (p = 0.002),
increase in eggs production by D. obtusa individuals was detected in the different media after the CaCO3 addition. Conversely, a corresponding highly significant (p = 0.0007), decrease in the production of new-borns, accompanied
by the degeneration of about 78% of the produced eggs, was detected in the different media after liming. Our results suggest
that in Lake Orta the actual irregular abundance of the studied Daphnia species and the eggs degeneration phenomenon, observed
in our study, could be largely attributed to the interspecific competition resulting from species-specific sensitivity to
the continuous variations in the lake water Chemistry after the liming operation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
82.
Al-Soud WA Ouis IS Li DQ Ljungh S Wadström T 《FEMS immunology and medical microbiology》2005,44(2):177-182
The inhibitory effect of human and porcine bile samples to detect Helicobacter DNA was studied by adding different concentrations of bile samples to PCR mixtures of six thermostable DNA polymerases containing cagA specific primers and Helicobacter pylori DNA. PCR products were amplified by using the Rotorgene system and SYBR Green I. Among the six DNA polymerases tested, rTth had the lowest sensitivity to bile inhibitors, whereas Taq and Tfl had the highest sensitivity. Bile proteins did not inhibit AmpliTaq DNA polymerase, whereas the fraction containing mainly bile acids and their salts inhibited the amplification capacity of AmpliTaq. Heating human bile at 98 degrees C and adding casein and formamide to the reaction mixture reduced the PCR inhibitory effect of bile. Therefore, a pre-PCR treatment based on dilution and heating of bile, adding casein and formamide to the reaction mixture of rTth DNA polymerase was found efficient to amplify DNA directly in bile. 相似文献
83.
84.
Alpha lipoic acid prevents doxorubicin‐induced nephrotoxicity by mitigation of oxidative stress,inflammation, and apoptosis in rats 下载免费PDF全文
El‐Sayed M. El‐Sayed Ahmed M. Mansour Waleed S. El‐Sawy 《Journal of biochemical and molecular toxicology》2017,31(9)
This study aimed to evaluate the protective effects of alpha lipoic acid (ALA) against doxorubicin (DOX)‐induced nephrotoxicity in rats. A single dose of DOX (7.5 mg/kg i.v.) induced nephrotoxicity evidenced by significant elevations in kidney weight, kidney/body weight ratio, serum urea, creatinine, tumor necrosis factor alpha, and renal contents of malondialdehyde, nitric oxide, cyclooxygenase‐2, and caspase‐3. Also, it causes significant reduction in final body weight, serum albumin, renal contents of reduced glutathione and superoxide dismutase activity. Histopathological changes in the kidney tissue confirmed the nephrotoxic effect. In contrast, pretreatment with ALA (50 mg/kg, orally) for 14 days before DOX and for 7 days after DOX administration mitigated renal toxicity evidenced by greater improvement in the examined oxidative stress, inflammation, and apoptosis parameters. In conclusion, ALA had promising protective effects against DOX‐induced nephrotoxicity that might be attributed to its antioxidant, anti‐inflammatory, and antiapoptoic activities. 相似文献
85.
Cheung AW Danho W Swistok J Qi L Kurylko G Rowan K Yeon M Franco L Chu XJ Chen L Yagaloff K 《Bioorganic & medicinal chemistry letters》2003,13(7):1307-1311
A series of MT-II related cyclic peptides, based on potent but non-selective hMC4R agonist (Penta-c[Asp-His(6)-DPhe(7)-Arg(8)-Trp(9)-Lys]-NH(2)) was prepared in which His(6) residue was systematically substituted. Two of the most interesting peptides identified in this study are Penta-c[Asp-5-ClAtc-DPhe-Arg-Trp-Lys]-NH(2) and Penta-c[Asp-5-ClAtc-DPhe-Cit-Trp-Lys]-NH(2) which are potent hMC4R agonists and are either inactive or weak partial agonists (not tested for their antagonist activities) in hMC1R, hMC3R and hMC5R agonist assays. 相似文献
86.
Joshua C. Anderson Christopher D. Willey Amitkumar Mehta Karim Welaya Dongquan Chen Christine W. Duarte Pooja Ghatalia Waleed Arafat Ankit Madan Sunil Sudarshan Gurudatta Naik William E. Grizzle Toni K. Choueiri Guru Sonpavde 《PloS one》2015,10(9)
Despite the widespread use of kinase-targeted agents in clear cell renal cell carcinoma (CC-RCC), comprehensive kinase activity evaluation (kinomic profiling) of these tumors is lacking. Thus, kinomic profiling of CC-RCC may assist in devising a classification system associated with clinical outcomes, and help identify potential therapeutic targets. Fresh frozen CC-RCC tumor lysates from 41 clinically annotated patients who had localized disease at diagnosis were kinomically profiled using the PamStation®12 high-content phospho-peptide substrate microarray system (PamGene International). Twelve of these patients also had matched normal kidneys available that were also profiled. Unsupervised hierarchical clustering and supervised comparisons based on tumor vs. normal kidney and clinical outcome (tumor recurrence) were performed and coupled with advanced network modeling and upstream kinase prediction methods. Unsupervised clustering analysis of localized CC-RCC tumors identified 3 major kinomic groups associated with inflammation (A), translation initiation (B), and immune response and cell adhesions (C) processes. Potential driver kinases implicated include PFTAIRE (PFTK1), PKG1, and SRC, which were identified in groups A, B, and C, respectively. Of the 9 patients who had tumor recurrence, only one was found in Group B. Supervised analysis showed decreased kinase activity of CDK1 and RSK1-4 substrates in those which progressed compared to others. Twelve tumors with matching normal renal tissue implicated increased PIM’s and MAPKAPK’s in tumors compared to adjacent normal renal tissue. As such, comprehensive kinase profiling of CC-RCC tumors could provide a functional classification strategy for patients with localized disease and identify potential therapeutic targets. 相似文献
87.
Arch G. Mainous III Robert U. Wright Mary M. Hulihan Waleed O. Twal Christine E. McLaren Vanessa A. Diaz Gordon D. McLaren W. Scott Argraves Althea M. Grant 《Biometals》2014,27(1):135-141
We sought to examine the relationship between elevated transferrin saturation (TS) and measures of health status (telomere length and patient-reported health-related quality of life) to assess whether elevated TS is associated with negative patient outcomes beyond increased risk for morbidity and mortality, using a cross-sectional analysis of the Hemochromatosis and Iron Overload Screening Study supplemented with assays for leukocyte telomere length in adults ≥25 years old (n = 669). Among individuals with elevated TS (≥45 % for women and ≥50 % for men), who also had a usual source of care, only 5.2 % reported ever being told by a doctor that they had an elevated iron condition. In a fully adjusted general linear regression model controlling for demographic characteristics as well as health conditions associated with iron overload, elevated TS versus non-elevated TS was associated with worse general health status (60.4 vs. 63.8, P < 0.05), mental health status (76.5 vs. 82.2, P < 0.0001) and shorter telomere length (241.4 vs. 261.3, P < 0.05). Increased surveillance of elevated TS may be in order as elevated TS is associated with decreased health status and very few patients with elevated TS are aware of their condition. 相似文献
88.
Rapita Sood Waleed Minzel Gilad Rimon Sharon Tal Liza Barki-Harrington 《The Journal of biological chemistry》2014,289(45):31473-31479
The enzyme cyclooxygenase-2 (COX-2) plays an important role in the kidney by up-regulating the production of the vasoconstrictor hormone angiotensin II (AngII), which in turn down-regulates COX-2 expression via activation of the angiotensin II type 1 receptor (AT1) receptor. Chemical inhibition of the catalytic activity of COX-2 is a well-established strategy for treating inflammation but little is known of cellular mechanisms that dispose of the protein itself. Here we show that in addition to its indirect negative feedback on COX-2, AT1 also down-regulates the expression of the COX-2 protein via a pathway that does not involve G-protein or β-arrestin-dependent signaling. Instead, AT1 enhances the ubiquitination and subsequent degradation of the enzyme in the proteasome through elements in its cytosolic carboxyl tail (CT). We find that a mutant receptor that lacks the last 35 amino acids of its CT (Δ324) is devoid of its ability to reduce COX-2, and that expression of the CT sequence alone is sufficient to down-regulate COX-2. Collectively these results propose a new role for AT1 in regulating COX-2 expression in a mechanism that deviates from its canonical signaling pathways. Down-regulation of COX-2 by a short peptide that originates from AT1 may present as a basis for novel therapeutic means of eliminating excess COX-2 protein. 相似文献
89.
Al Gadban MM German J Truman JP Soodavar F Riemer EC Twal WO Smith KJ Heller D Hofbauer AF Oates JC Hammad SM 《Cellular immunology》2012,276(1-2):42-51
Systemic lupus erythematosus (SLE) patients display impaired endothelial nitric oxide synthase (eNOS) function required for normal vasodilatation. SLE patients express increased compensatory activity of inducible nitric oxide synthase (iNOS) generating excess nitric oxide that may result in inflammation. We examined the effects of genetic deletion of NOS2 and NOS3, encoding iNOS and eNOS respectively, on accelerated vascular disease in MRL/lpr lupus mouse model. NOS2 and NOS3 knockout (KO) MRL/lpr mice had higher plasma levels of triglycerides (23% and 35%, respectively), ceramide (45% and 21%, respectively), and sphingosine 1-phosphate (S1P) (21%) compared to counterpart MRL/lpr controls. Plasma levels of the anti-inflammatory cytokine interleukin 10 (IL-10) in NOS2 and NOS3 KO MRL/lpr mice were lower (53% and 80%, respectively) than counterpart controls. Nodule-like lesions in the adventitia were detected in aortas from both NOS2 and NOS3 KO MRL/lpr mice. Immunohistochemical evaluation of the lesions revealed activated endothelial cells and lipid-laden macrophages (foam cells), elevated sphingosine kinase 1 expression, and oxidized low-density lipoprotein immune complexes (oxLDL-IC). The findings suggest that advanced vascular disease in NOS2 and NOS3 KO MRL/lpr mice maybe mediated by increased plasma triglycerides, ceramide and S1P; decreased plasma IL-10; and accumulation of oxLDL-IC in the vessel wall. The results expose possible new targets to mitigate lupus-associated complications. 相似文献
90.
Yaseen M. Arabi Abdulrahman Aljumah Ousama Dabbagh Hani M. Tamim Asgar H. Rishu Abdulmajeed Al-Abdulkareem Bandar Al Knawy Ali H. Hajeer Waleed Tamimi Antoine Cherfan 《CMAJ》2010,182(18):1971-1977