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Superoxide Anion Production and Expression of gp91phox and p47phox Are Increased in Glomeruli and Proximal Tubules of Cisplatin‐Treated Rats 下载免费PDF全文
Joyce Trujillo Eduardo Molina‐Jijón Omar Noel Medina‐Campos Rafael Rodríguez‐Muñoz José Luis Reyes Diana Barrera José Pedraza‐Chaverri 《Journal of biochemical and molecular toxicology》2015,29(4):149-156
The chemotherapeutic drug cisplatin has some side effects including nephrotoxicity that has been associated with reactive oxygen species production, particularly superoxide anion. The major source of superoxide anion is nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) oxidase. However, the specific segment of the nephron in which superoxide anion is produced has not been identified. Rats were sacrificed 72 h after cisplatin injection (7.5 mg/kg), and kidneys were obtained to isolate glomeruli and proximal and distal tubules. Cisplatin induced superoxide anion production in glomeruli and proximal tubules but not in distal tubules. This enhanced superoxide anion production was prevented by diphenylene iodonium, an inhibitor of NADPH oxidase. Consistently, this effect was associated with the increased expression of gp91phox and p47phox, subunits of NADPH oxidase. The enhanced superoxide anion production in glomeruli and proximal tubules, associated with the increased expression of gp91phox and p47phox, is involved in the oxidative stress in cisplatin‐induced nephrotoxicity. 相似文献
163.
Laura Del Latte Francesca Bortolin Omar Rota-Stabelli Giuseppe Fusco Lucio Bonato 《ZooKeys》2015,(510):31-47
Stenotaenia is one of the largest and most widespread genera of geophilid centipedes in the Western Palearctic, with a very uniform morphology and about fifteen species provisionally recognized. For a better understanding of Stenotaenia species-level taxonomy, we have explored the possibility of using molecular data. As a preliminary assay, we sampled twelve populations, mainly from the Italian region, and analyzed partial sequences of the two genes COI and 28S. We employed a DNA-barcoding approach, complemented by a phylogenetic analysis coupled with divergence time estimation. Assuming a barcoding gap of 10–16% K2P pairwise distances, we found evidence for the presence of at least six Stenotaenia species in the Italian region, which started diverging about 50 million years ago, only partially matching with previously recognized species. We found that small-sized oligopodous species belong to a single clade that originated about 33 million years ago, and obtained some preliminary evidence of the related genus Tuoba being nested within Stenotaenia. 相似文献
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Mesarwi Omar A. Sharma Ellora V. Jun Jonathan C. Polotsky Vsevolod Y. 《Sleep and biological rhythms》2015,13(1):2-17
Sleep and Biological Rhythms - It has recently become clear that obstructive sleep apnea (OSA) is an independent risk factor for the development of metabolic syndrome, a disorder of defective... 相似文献
167.
Gut microbiota richness promotes its stability upon increased dietary fibre intake in healthy adults 下载免费PDF全文
168.
Nurlisa Yusuf Ammar Zakaria Mohammad Iqbal Omar Ali Yeon Md Shakaff Maz Jamilah Masnan Latifah Munirah Kamarudin Norasmadi Abdul Rahim Nur Zawatil Isqi Zakaria Azian Azamimi Abdullah Amizah Othman Mohd Sadek Yasin 《BMC bioinformatics》2015,16(1)
Background
Effective management of patients with diabetic foot infection is a crucial concern. A delay in prescribing appropriate antimicrobial agent can lead to amputation or life threatening complications. Thus, this electronic nose (e-nose) technique will provide a diagnostic tool that will allow for rapid and accurate identification of a pathogen.Results
This study investigates the performance of e-nose technique performing direct measurement of static headspace with algorithm and data interpretations which was validated by Headspace SPME-GC-MS, to determine the causative bacteria responsible for diabetic foot infection. The study was proposed to complement the wound swabbing method for bacterial culture and to serve as a rapid screening tool for bacteria species identification. The investigation focused on both single and poly microbial subjected to different agar media cultures. A multi-class technique was applied including statistical approaches such as Support Vector Machine (SVM), K Nearest Neighbor (KNN), Linear Discriminant Analysis (LDA) as well as neural networks called Probability Neural Network (PNN). Most of classifiers successfully identified poly and single microbial species with up to 90% accuracy.Conclusions
The results obtained from this study showed that the e-nose was able to identify and differentiate between poly and single microbial species comparable to the conventional clinical technique. It also indicates that even though poly and single bacterial species in different agar solution emit different headspace volatiles, they can still be discriminated and identified using multivariate techniques. 相似文献169.
Omar EstradaJuan Manuel González-Guzmán Margarita Salazar-BookamanAna Z. Fernández Alfonso CardozoClaudia Alvarado-Castillo 《Phytomedicine》2011,18(6):464-469
Pomolic acid has recently shown hypotensive effect in rats. The purpose of this investigation was to determine the vascular effects of this triterpenoid and to examine its mode of action. Functional experiments in rat aortic rings precontracted with norepinephrine were performed to evaluate the vasorelaxant effect of pomolic acid. This triterpenoid induced a vasorelaxation (IC50 = 2.45 μM) in a concentration- and endothelium-dependent manner and showed no effect on contractions evoked by KCl (25 mM). Pre-treatment of aortic rings with l-NAME (100 μM), methylene blue (100 μM) or glibenclamide (10 μM), totally prevented the vasorelaxation induced by pomolic acid, while indomethacin (10 μM) had no effect on this response. Additionally, pomolic acid relaxation was unaffected under the muscarinic- and β-adrenergic-receptor blocked ensured for atropine and propanolol respectively (10 μM each). In contrast, the vasorelaxant effect of pomolic acid was abolished under the purinergic-receptor blocked ensured for suramin (10 μM). Finally, apyrase (0.8 U/ml) an enzyme which hydrolyses ATP and ADP did not affect pomolic acid relaxation. In summary, pomolic acid has a potent endothelium-dependent vasorelaxant effect, possibly acting through the direct activation of endothelial purinergic receptors via NO-cGMP signaling pathway, which could be part of the mechanism underlying its hypotensive effect. 相似文献
170.
The mammary gland is composed of two major cellular compartments: a highly dynamic epithelium that undergoes cycles of proliferation, differentiation and apoptosis in response to local and endocrine signals and the underlying stroma comprised of fibroblasts, endothelial cells and adipocytes, which collectively form the mammary fat pad. Breast cancer originates from subversions of normal growth regulatory pathways in mammary epithelial cells due to genetic mutations and epigenetic modifications in tumor suppressors, oncogenes and DNA repair genes. Diet is considered a highly modifiable determinant of breast cancer risk; thus, considerable efforts are focused on understanding how certain dietary factors may promote resistance of mammary epithelial cells to growth dysregulation. The recent indications that stromal cells contribute to the maintenance of the mammary epithelial ‘niche’ and the increasing appreciation for adipose tissue as an endocrine organ with a complex secretome have led to the novel paradigm that the mammary stromal compartment is itself a relevant target of bioactive dietary factors. In this review, we address the potential influence of dietary factors on mammary epithelial-stromal bidirectional signaling to provide mechanistic insights into how dietary factors may promote early mammary epithelial differentiation to decrease adult breast cancer risk. 相似文献