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151.
An aqueous and alcoholic extract of the roots of Aralia cachemirica (Araliaceae) were evaluated for hypoglycemic activity in normal fasted and glucose induced hyperglycemic rats. The aqueous and alcoholic extracts at a dose of 250 mg/kg showed statistically significant (p < 0.01) hypoglycemic activity in glucose loaded animals however no effect was observed in normal fasted rats. 相似文献
152.
Toxicity and detoxification of lipid-derived aldehydes in cultured retinal pigmented epithelial cells 总被引:1,自引:0,他引:1
Choudhary S Xiao T Srivastava S Zhang W Chan LL Vergara LA Van Kuijk FJ Ansari NH 《Toxicology and applied pharmacology》2005,204(2):122-134
Age-related macular degeneration (ARMD) is the leading cause of blindness in the developed world and yet its pathogenesis remains poorly understood. Retina has high levels of polyunsaturated fatty acids (PUFAs) and functions under conditions of oxidative stress. To investigate whether peroxidative products of PUFAs induce apoptosis in retinal pigmented epithelial (RPE) cells and possibly contribute to ARMD, human retinal pigmented epithelial cells (ARPE-19) were exposed to micromolar concentrations of H2O2, 4-hydroxynonenal (HNE) and 4-hydroxyhexenal (HHE). A concentration- and time-dependent increase in H2O2-, HNE-, and HHE-induced apoptosis was observed when monitored by quantifying DNA fragmentation as determined by ELISA, flow cytometry, and Hoechst staining. The broad-spectrum inhibitor of apoptosis Z-VAD inhibited apoptosis. Treatment of RPE cells with a thionein peptide prior to exposure to H2O2 or HNE reduced the formation of protein-HNE adducts as well as alteration in mitochondrial membrane potential and apoptosis. Using 3H-HNE, various metabolic pathways to detoxify HNE by ARPE-19 cells were studied. The metabolites were separated by HPLC and characterized by ElectroSpray Ionization-Mass Spectrometry (ESI-MS) and gas chromatography-MS. Three main metabolic routes of HNE detoxification were detected: (1) conjugation with glutathione (GSH) to form GS-HNE, catalyzed by glutathione-S-transferase (GST), (2) reduction of GS-HNE catalyzed by aldose reductase, and (3) oxidation of HNE catalyzed by aldehyde dehydrogenase (ALDH). Preventing HNE formation by a combined strategy of antioxidants, scavenging HNE by thionein peptide, and inhibiting apoptosis by caspase inhibitors may offer a potential therapy to limit retinal degeneration in ARMD. 相似文献
153.
El Ansari W 《Public health》2005,119(9):758-770
Community/campus research collaborations face multiple challenges. An understanding of the community's background, history, habits and traditions, values and mode of operations is required. This article narrates a 3-year experience of undertaking collaborative public health research with five disadvantaged communities in various provinces of South Africa. Based on the experience, five main challenges exist: the value systems of those collaborating in the research; the stakeholders' costs and benefits of being involved; issues of empowerment and capacity transfer; the need for multidisciplinary research approaches; and the prerequisite of the clarity of relationships and roles between researcher and community. Categorized under the five main challenges are examples of 19 interlacing 'concepts' that detailed the South African research partnership from the perspective of the processes, dealings and daily difficulties. Examples of the challenges and concepts are highlighted from the author's research experiences with disadvantaged communities. These challenges increase exponentially with the inclusion of more research sites, more stakeholders or when undertaking cluster research. Possible preventative measures or solutions to the problems are suggested. Both the 'town' and 'gown' partners are required to attend to a multitude of factors when embarking on collaborative community-based research. 相似文献
154.
Intramedullary nailing through the piriform fossa results in some cases in loss of abduction strength and persistent pain. Nail insertion at the tip of the greater trochanter may be favourable. The aim of this study was to assess (possible) iatrogenic injury to the abductor and external rotator musculature, branches of the superior gluteal nerve and branches of the MFCA in relation to the two different entry points. In 10 fresh human cadaver femurs, five unreamed femoral nails (UFN) were inserted through the piriform fossa and five AO prototype nails (AFN) through the trochanteric tip. The iatrogenic injury at each nailing procedure was assessed. Various muscles and tendons, branches of the MFCA along with the hip joint capsule were injured or largely at risk during nail insertion through the piriform fossa. Most of these structures were not exposed during insertion through the trochanteric tip. The reported clinical morbidity after nailing through the piriform fossa may find its origin in direct soft tissue injury and may be reduced by choosing a lateral nail entry point. 相似文献
155.
156.
Kumar S Ansari J Blackburn ME Weerasena N 《Interactive Cardiovascular and Thoracic Surgery》2005,4(5):484-485
A term female newborn presented with right atrial isomerism and infra-diaphragmatic total anomalous pulmonary venous drainage associated with complex cardiac anatomy. The repair was performed utilizing circulatory arrest in deep hypothermia. However, in the post-operative period the patient could not be weaned off mechanical ventilation and underwent cardiac catheterisation. This revealed major aortopulmonary collaterals, which were occluded with coils. We review the literature with specific focus on the occurrence of this unusual combination and its implication in the management during the postoperative period. 相似文献
157.
158.
This article deals with a prospective study on the cytochemical, functional, and proliferative characteristics of promonocytes and bone marrow and peripheral blood monocytes of 20 patients with acute monocytic leukemia and 7 patients with chronic monocytic leukemia. The results show a wide variation in the peroxidase and esterase activities in these cells, whereas the percentages of mononuclear phagocytes with Fc gamma and C3b receptors did not differ appreciably from those in normal individuals. A discriminant analysis of these data and corresponding data from normal individuals showed that a below-normal peroxidase activity of circulating monocytes has predictive value for the presence of monocytic leukemia; a below-normal esterase activity has less, but nevertheless some, predictive value in this respect. An increase in the percentage of circulating monocytes, a decrease in the percentage of Fc gamma or C3b receptors, and a decline in the ability to phagocytose bacteria has no predictive value for the presence of monocytic leukemia. The mean percentage of patients' promonocytes that incorporated 3H-thymidine amounted to 80.9%, which is close to the control value in normal individuals. The mean values for the labeling indices of cultured bone marrow and peripheral blood monocytes are 1.0% and 0.74%, respectively; when 3H-thymidine was added to whole blood, the labeling index of the monocytes amounted to 3.6%. These percentages are only a little higher than those found for monocytes of normal individuals. These results indicate that the majority of the circulating monocytes in acute and chronic monocytic leukemia are not actively dividing or blast cells. 相似文献
159.
160.