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891.
Al-Rashdan I Canatan H Al-Maghrebi M Yousif MH Khan SA Benter IF 《Cell biochemistry and function》2007,25(4):455-461
The present study was designed to see if acute local inhibition of Ras-GTPase before or after ischemia (during perfusion) would produce protection against ischemia and reperfusion (I/R)-induced cardiac dysfunction. The effect of glibenclamide, an inhibitor of cardiac mitochondrial ATP-sensitive potassium (mitoK(ATP)) channels, on Ras-GTPase-mediated cardioprotection was also studied. A 40 min episode of global ischemia followed by a 30 min reperfusion in perfused rat hearts produced significantly impaired cardiac function, measured as left ventricular developed pressure (P(max)) and left ventricular end-diastolic pressure (LVEDP). Perfusion with Ras-GTPase inhibitor FPT III before I/R [FPT(pre)], significantly enhanced cardiac recovery in terms of left ventricular contractility. P(max) was significantly higher at the end of 30 min reperfusion in FPT(pre)-treated hearts compared to pre-conditioned hearts. However, the degree of improvement in left ventricular contractility was significantly less when FPT III was given only after ischemia during reperfusion [FPT(post)]. Combination treatment with FPT III and glibenclamide before I/R resulted in significant reduction of FPT III-mediated cardioprotection. These data suggest that activation of Ras-GTPase signaling pathways during ischemia are critical in the development of left ventricular dysfunction and that opening of mitoK(ATP) channels, at least in part, contributes to cardioprotection produced by Ras-GTPase inhibition. 相似文献
892.
893.
Consequences of epididymal ligation on prepubertal rats 总被引:1,自引:0,他引:1
Aktug H Ozdedeli K Altay B Cüreklibatur I Turna B Yilmaz O 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2007,29(1):50-56
OBJECTIVE: To study prospectively experimental effects of unilateral epididymal obstruction on testis and epididymis histopathologically in prepubertal rats. STUDY DESIGN: Organ weights, mean seminiferous tubule diameter (MSTD), mean ductus epididymis diameter (MDED), mean tubular biopsy scores (MTBS) and histopathology of 21 male albino Wistar rats were compared with the immunostaining affinity of anti-desmin, anti-vimentin, anti-laminin and anti-collagen antibodies. RESULTS: Statistical analysis of mean weight of testes, MTBS, mean epididymal weight, MDED and MSTD was significant. Evaluation of testis and epididymis revealed cellular damage, basal membrane impairment and granulomatous infiltration. CONCLUSION: Histopathologic alterations with MSTD are early indicators for ipsilateral and contralateral injury. Even the presence of criteria such as intactness and cellular integrity does not guarantee there is no sperm leakage or immunologic damage. Therefore the impairment of basal integrity is a switch code in determining spermatogenic failure. 相似文献
894.
Ibrahim MA Elbehairy AM Ghoneim MA Amer HA 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(3-4):215-222
The current study was carried out to evaluate the potency of curcumin and chlorophyllin as natural antioxidants to reduce the oxidative stress markers induced by cyclophosphamide (CP) and benzo[a]pyrene [B(a)P] which were used as free radical inducers. For this purpose, 126 male albino rats were used. The animals were assigned into 4 main groups: negative control group; oxidant-treated group (subdivided into two subgroups: cyclophosphamide-treated group and benzo[a]pyrene-treated group); curcumin-treated group; and chlorophyllin-treated group. Liver samples were collected after two days post the oxidant inoculation and at the end of the experimental period (10 weeks). These samples were examined for determination of liver microsomal malondialdehyde (MDA), DNA fragmentation, restriction fragment length polymorphism (RFLP) and 8-hydroxy deoxyguanosine (8-OHdG) concentration. Both CP and B(a)P caused increments in DNA fragmentation percentages, liver microsomal MDA, concentration of 8-OHdG and induced point mutation. Treatment of rats with either curcumin or chlorophyllin revealed lower DNA fragmentation percentages, liver microsomal MDA concentration, concentration of 8-OHdG and prevented induction of mutations, i.e., reversed the oxidative stress induced by CP and B(a)P and proved that they were capable of protecting rats against the oxidative damage evoked by these oxidants. 相似文献
895.
Steert K El-Sayed I Van der Veken P Krishtal A Van Alsenoy C Westrop GD Mottram JC Coombs GH Augustyns K Haemers A 《Bioorganic & medicinal chemistry letters》2007,17(23):6563-6566
The synthesis of novel dipeptidyl alpha-fluorovinyl sulfones using a Horner-Wadsworth-Emmons approach on N-Boc-l-phenylalaninal is described. Inhibitory assays against a Leishmania mexicana cysteine protease (CPB2.8DeltaCTE) revealed low biological activity. Relative rates of Michael additions of 2'-(phenethyl)thiol with vinyl sulfone and alpha-fluorovinyl sulfone were determined, and ab initio calculations on several Michael acceptor model structures were performed; both were in agreement with the biological testing results. 相似文献
896.
Macrophage inflammatory protein-1α: A link between innate immunity and familial mediterranean fever?
Dizdar O Kalyoncu U Karadag O Akdogan A Kiraz S Ertenli I Barista I Calguneri M 《Cytokine》2007,37(1):92-95
The aim of this study is to investigate the relationship between chemokines and the inflammation in Familial Mediterranean Fever (FMF). Forty-nine patients with FMF (41 in remission and 8 in acute attack period) and 20 healthy controls were included in the study. Serum levels of macrophage inflammatory protein-1alpha (MIP-1alpha) were assessed in the patients and the controls, along with other parameters of disease activity, i.e., fibrinogen, C-reactive protein and erythrocyte sedimentation rate. Serum MIP-1alpha levels of the patients with FMF in acute attack period were significantly higher than the patients in remission and healthy controls (p=0.02 and p=0.038, respectively). MIP-1alpha levels were weakly correlated with CRP (r=0.32, p=0.032) levels. MIP-1alpha may have a role in the pathogenesis of FMF attacks. MIP-1alpha and other chemokines may constitute a link between the innate immune system and FMF. 相似文献
897.
The oxidative stress theory of aging offers the best mechanistic elucidation of the aging phenomenon and other age-related
diseases. The susceptibility of an individual depends on the antioxidant status of the body. In humans, the antioxidant system
includes a number of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT), nonenzymatic antioxidants
such as glutathione (GSH), protein –SH, ascorbic acid, and uric acid, and dietary antioxidants. Antioxidant enzymes form the
first line of defense against reactive oxygen species. In an earlier report, we showed that the plasma antioxidant potential
in humans decreases as a function of age and that there are compensatory mechanisms operating in the body which are induced
to maintain the antioxidant capacity during aging. In the present study, we report the relationship between human aging and
antioxidant enzymes SOD and CAT; we also correlate the activity of these enzymes with the antioxidant capacity of the plasma.
Our results show a significantly higher plasma SOD and CAT activity in older individuals than in younger individuals. The
induction in activity of SOD and CAT during human aging may be a compensatory response of the individual to an increased oxidative
stress. 相似文献
898.
Hassanen Eman I. Hussien Ahmed M. Hassan Neven H. Ibrahim Marwa A. Mehanna Sally 《Neurochemical research》2022,47(10):3051-3062
Neurochemical Research - Pesticides are widely used in agriculture to kill pests, but their action is non-selective and results in several hazardous effects on humans and animals. Pesticide... 相似文献
899.
Polat Derya Genc Durmaz Yasar Konar Nevzat Pirouzian Haniyeh Rasouli Toker Omer Said Palabiyik Ibrahim Tasan Murat 《Journal of applied phycology》2022,34(1):375-383
Journal of Applied Phycology - In this study, dried or encapsulated Nannochloropsis oculata microalgal biomass was used in spread samples (0.00–0.75 g (100 g)?1... 相似文献
900.
Elham A. Al-Taifi Al-Aghbari Sama A. Z. El-Ossaily Yasser A. Yeap Guan-Yeow Marae Islam S. Ibrahim Omaima F. Bakhite Etify A. 《Russian Journal of Bioorganic Chemistry》2022,48(2):423-429
Russian Journal of Bioorganic Chemistry - This work describes facile routes towards the synthesis of some novel thiophene derivatives. Thus, condensation of thiophene-2-carboxaldehyde with... 相似文献