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41.
42.
Ibrahim M. El-Deen El-Zend Manar A. Tantawy Mohamed A. Barakat Lamiaa A. A. 《Russian Journal of Bioorganic Chemistry》2022,48(2):380-390
Russian Journal of Bioorganic Chemistry - A series of coumarin and aza-coumarin derivatives (II–IX) were synthesized and identified using IR, 1H NMR, and 13C NMR spectral data. All the... 相似文献
43.
The pathogenesis of acute kidney injury (AKI) occurring due to sepsis is incompletely understood. Endothelial activation, defined as up-regulation of adhesion molecules by proinflammatory cytokines, may be central to the development of sepsis-induced AKI. Our aim was to determine levels of circulating adhesion molecules endothelial (E)-selectin, intercellular adhesion molecule (ICAM), and vascular cell adhesion molecule (VCAM), inflammatory mediators; tumor necrosis factor-α (TNF-α) and transforming growth factor-β (TGF-β), vasoactive mediators; endothelin-1 (ET-1) and nitric oxide (NO), soluble receptor for advanced glycated end products (sRAGE) and serum fetuin-A in septic AKI patients before and after antibiotic therapy. Nineteen AKI patients with sepsis and fifteen healthy controls were enrolled in this prospective study. Results revealed that 12 weeks of therapy caused amelioration of endothelial and inflammatory injuries as well as renal function markers. Moreover, the positive correlations between levels of RAGE and E-selectin (r=0.88), ET-1 (r=0.90), and TNF-α (r=0.94) and negative with NO (r=-0.75-0.95) suggest that possible interaction of RAGE and inflammation may contribute to endothelial dysfunction in septic AKI patients. 相似文献
44.
ElFihry Raouia Elmessaoudi-Idrissi Mohcine Jadid Fatima-Zahra Zaidane Imane Chihab Hajar Tahiri Mohamed Kabine Mostafa Badre Wafaa Chemin Isabelle Marchio Agnes Pineau Pascal Ezzikouri Sayeh Benjelloun Soumaya 《中国病毒学》2020,35(5):566-574
Virologica Sinica - Hepatitis C virus (HCV) is still one of the main causes of liver disease worldwide. Metabolic disorders, including non-alcoholic fatty liver disease (NAFLD), induced by HCV have... 相似文献
45.
Emilien Loeuillard Haquima El Mourabit Lin Lei Sara Lemoinne Chantal Housset Axelle Cadoret 《生物化学与生物物理学报:疾病的分子基础》2018,1864(12):3688-3696
Portal myofibroblasts (PMF) form a sub-population of highly proliferative and proangiogenic liver myofibroblasts that derive from portal mesenchymal progenitors. Endoplasmic reticulum (ER) stress was previously shown to modulate fibrogenesis, notably in the liver. Our aim was to determine if ER stress occurred in PMF and affected their functions. PMF were obtained after their expansion in vivo from bile duct-ligated (BDL) rats and referred to as BDL PMF. Compared to standard PMF obtained from normal rats, BDL PMF were more myofibroblastic, as assessed by higher alpha-smooth muscle actin expression and collagen 1 production. Their proangiogenic properties were also higher, whereas their proliferative and migratory capacities were lower. CHOP expression was detected in the liver of BDL rats, at the leading edge of portal fibrosis where PMF accumulate. BDL PMF displayed ER dilatation and an overexpression of the PERK pathway downstream targets, Chop, Gadd34 and Trb3, in comparison with standard PMF. In vitro, the induction of ER stress by tunicamycin in standard PMF, caused a decrease in their proliferative and migratory activity, and an increase in their proangiogenic activity, without affecting their myofibroblastic differentiation. Conversely, the treatment of BDL PMF with the PERK inhibitor GSK2656157 reduced ER stress, which caused a decrease in their angiogenic properties, and restored their proliferative and migratory capacity. In conclusion, PMF develop ER stress as they expand with the progression of fibrosis, which further increases their proangiogenic activity, but also inhibits their proliferation and migration. This phenotypic switch may restrict PMF expansion while they support angiogenesis. 相似文献
46.
Purkis Sam J. Gleason Arthur C. R. Purkis Charlotte R. Dempsey Alexandra C. Renaud Philip G. Faisal Mohamed Saul Steven Kerr Jeremy M. 《Coral reefs (Online)》2019,38(3):467-488
Coral Reefs - With compelling evidence that half the world’s coral reefs have been lost over the last four decades, there is urgent motivation to understand where reefs are located and their... 相似文献
47.
Ahmed Fahal EL Sheikh Mahgoub Ahmed Mohamed EL Hassan Angom Osman Jacoub Doaa Hassan 《PLoS neglected tropical diseases》2015,9(3)
Mycetoma is a unique neglected tropical disease which is endemic in what is known as the “mycetoma belt”. The disease has many devastating impacts on patients and communities in endemic area and is characterised by massive deformity, destruction and disability. Mycetoma is commonly seen in the foot and hand and less frequent in other parts of the body. Mycetoma of the head and neck is a rarity and is associated with high morbidity and even mortality if not treated early. In this communication we report on 49 patients with head and neck mycetoma followed up at the Mycetoma Research Centre in Khartoum. Most of the reported patients had actinomycetoma and the majority were young adult males from mycetoma endemic areas in the Sudan. Most of them were students, farmers and workers. Prior to presentation the majority had long disease duration and the cause was multifactorial. Advanced disease with massive lesion, deformity and disability was the common presentation. There was no obvious history of local trauma, familial tendency or other predisposing factor identified in this group of patients. MRI and CT scan were the most accurate diagnostic tools to determine the disease extent. The treatment outcome was rather poor and characterised by low cure rate, poor outcome and high follows-up dropout. Such a gloomy outcome calls for structured and objective health education programs. 相似文献
48.
Mohamed SA Fahmy AS Mohamed TM Hamdy SM 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2005,142(3):308-316
The ornithine-urea cycle has been investigated in Fasciola gigantica. Agrinase had very high activity compared to the other enzymes. Carbamoyl phosphate synthetase and ornithine carbamoyltransferase had very low activity. A moderate enzymatic activity was recorded for argininosuccinate synthetase and argininosuccinate lyase. The low levels of F. gigantica urea cycle enzymes except to the arginase suggest the urea cycle is operative but its role is of a minor important. The high level of arginase activity may benefit for the hydrolysis of the exogenous arginine to ornithine and urea. Two arginases Arg I and Arg II were separated by DEAE-Sepharose column. Further purification was restricted to Arg II with highest activity. The molecular weight of Arg II, as determined by gel filtration and SDS-PAGE, was 92,000. The enzyme was capable to hydrolyze l-arginine and to less extent l-canavanine at arginase:canavanase ratio (>10). The enzyme exhibited a maximal activity at pH 9.5 and Km of 6 mM. The optimum temperature of F. gigantica Arg II was 40 degrees C and the enzyme was stable up to 30 degrees C and retained 80% of its activity after incubation at 40 degrees C for 15 min and lost all of its activity at 50 degrees C. The order of effectiveness of amino acids as inhibitors of enzyme was found to be lysine>isoleucine>ornithine>valine>leucine>proline with 67%, 43%, 31%, 25%, 23% and 15% inhibition, respectively. The enzyme was activated with Mn2+, where the other metals Fe2+, Ca2+, Hg2+, Ni2+, Co2+ and Mg2+ had inhibitory effects. 相似文献
49.
A series of 10 3-(hetarylaminomethylene)quinolinediones, 12 3-(substituted aminopropenoyl)-4-hydroxyquinolinones, and 10 3-(substituted aminomethylene-5-oxo-pyrazolinyl)-4-hydroxyquinolinones were synthesized as novel enaminones derived from 3-(un)substituted 4-hydroxyquinolin-2(1H)-ones in 72-94% yields and assayed for their molluscicidal activities against Biomphalaria alexandrina and Lymnaea natalensis snails. Some of the tested enaminones presented high molluscicidal activities (LC(50)20ppm). The new compounds showed more potency against hatchability of B. alexandrina egg masses, the infection rate and prepatent period of the snails. In addition, these derivatives revealed potential larvicidal effects (100% mortality) on both miracidia and cercariae of Schistosoma mansoni at reduced exposure time. The selected active derivatives were examined against Daphnia magna and their nontoxic effect at all sublethal, lethal, and higher concentrations suggests that these compounds can play an important role as molluscicides and larvicides with environmental safe properties. 相似文献
50.
Amira Sfaxi-Bousbih Abdelilah Chaoui Ezzedine El Ferjani 《Biological trace element research》2010,137(1):110-116
Seeds of bean (Phaseolus vulgaris L.) were germinated by soaking in distilled water or copper chloride solution. The relationships among copper excess treatment,
germination rate, dry weight, sugar contents, and carbohydrase activities in cotyledon were investigated. Heavy metal stress
provoked a diminution in germination rate and biomass mobilization, as compared with the control. A drastic disorder in soluble
sugars export, especially glucose and fructose liberation, was also imposed after exposure to excess copper. This restricted
the starch and sucrose breakdown in reserve tissue, as evidenced by the inhibition in the activities of α-amylase and invertase
isoenzymes (soluble acid, soluble neutral, cell wall-bound acid). 相似文献