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In Drosophila melanogaster, p53 (Dmp53) is an important mediator of longevity. Expression of dominant-negative (DN) forms of Dmp53 in adult neurons, but not in muscle or fat body cells, extends lifespan. The lifespan of calorie-restricted flies is not further extended by simultaneously expressing DN-Dmp53 in the nervous system, indicating that a decrease in Dmp53 activity may be a part of the CR lifespan-extending pathway in flies. In this report, we show that selective expression of DN-Dmp53 in only the 14 insulin-producing cells (IPCs) in the brain extends lifespan to the same extent as expression in all neurons and this lifespan extension is not additive with CR. DN-Dmp53-dependent lifespan extension is accompanied by reduction of Drosophila insulin-like peptide 2 (dILP2) mRNA levels and reduced insulin signaling (IIS) in the fat body, which suggests that Dmp53 may affect lifespan by modulating insulin signaling in the fly.  相似文献   
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The main aim of this study is to determine the causes and the epidemiological aspects of sudden natural deaths. Data were collected from 545 sudden natural autopsies in UMMC, Kuala Lumpur over a five-year period, from 1st January 2000 to 31st December 2004. There were 475 males and 70 females. The largest number of sudden natural deaths was in the age group of 41-50 years. 35.8%, 30.5% and 11.7% of the patients were Chinese, Indian and Malay, respectively. A majority of the patients were married (59.8%) and came from the semiskilled-unskilled group (30.6%). The monthly distribution was almost constant. Cardiovascular diseases were the most important cause contributing 64.9% in sudden natural deaths.  相似文献   
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Hypercholesterolaemia, increase in lipid peroxidation and hyperhomocysteinaemia may contribute to the pathogenesis of atherosclerosis. This study was performed to examine the effects of repeatedly heated palm oil mixed with 2% cholesterol diet on atherosclerosis in oestrogen-deficient postmenopausal rats. Ovariectomy causes disruption of tunica intima layer of the rat aorta simulating a postmenopausal condition in females. Twenty-four ovariectomized female Sprague–Dawley rats were divided into four groups. The control group received 2% cholesterol diet without palm oil. A diet with 2% cholesterol content fortified with fresh, once-heated and five-times-heated palm oil was given to the other treatment groups. The rats were sacrificed at the end of 4 months of study and the aortic arch tissue was processed for histomorphometry and electron microscopy. On observation, there was disruption of the intimal layer of the ovariectomized rat aorta. There was no obvious ultrastructural change in the aorta of the rats fed with fresh palm oil. The ultrastructural changes were minimal with once-heated palm oil, in which there was a focal disruption of the endothelial layer. The focal disruption was more pronounced with five-times-heated palm oil. The results of this study show that the ingestion of fresh palm oil may have a protective effect on the aorta but such a protective action may be lost when the palm oil is repeatedly heated. The study may be clinically important for all postmenopausal women who are susceptible to atherosclerosis.  相似文献   
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Four commercial repellents were evaluated in the laboratory against Leptotrombidium deliense chiggers. Both in vitro and in vivo methods were used to determine repellency of the compounds. The repellents were Kellis (containing citronella oil, jojoba oil and tea tree oil), Kaps (containing citronella oil), BioZ (containing citronella oil, geranium oil and lemon grass oil) and Off (containing DEET). The combination of three active ingredients: citronella oil, geranium oil, lemon grass oil gave the highest repellency (87%) followed by DEET (84%). In vitro repellencies ranged from 73% to 87%. There was no significant difference between the four products. All the repellents had 100% in vivo repellency compared to 41-57% for the controls.  相似文献   
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International Journal of Clinical Pharmacy - Background Increased harmful effects of medication resulting from polypharmacy, especially among older patients, is a significant concern globally....  相似文献   
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ContextAtherosclerosis predisposes individuals to adverse cardiovascular events. Clinacanthus nutans L. (Acanthaceae) is a traditional remedy used for diabetes and inflammatory conditions.ObjectivesTo investigate the anti-atherosclerotic activity of a C. nutans leaf methanol extract (CNME) in a type 2 diabetic (T2D) rat model induced by a high-fat diet (HFD) and low-dose streptozotocin.Materials and methodsSixty male Sprague-Dawley rats were divided into five groups: non-diabetic fed a standard diet (C), C + CNME (500 mg/kg, orally), diabetic fed an HFD (DM), DM + CNME (500 mg/kg), and DM + Metformin (DM + Met; 300 mg/kg). Treatment with oral CNME and metformin was administered for 4 weeks. Fasting blood glucose (FBG), serum lipid profile, atherogenic index (AI), aortic tissue superoxide dismutase levels (SOD), malondialdehyde (MDA), and tumour necrosis factor-alpha (TNF-α) were measured. The rats’ aortas were stained for histological analysis and intima-media thickness (IMT), a marker of subclinical atherosclerosis.ResultsThe CNME-treated diabetic rats had reduced serum total cholesterol (43.74%; p = 0.0031), triglycerides (80.91%; p = 0.0003), low-density lipoprotein cholesterol (56.64%; p = 0.0008), AI (51.32%; p < 0.0001), MDA (60.74%; p = 0.0026), TNF-α (61.78%; p = 0.0002), and IMT (39.35%; p < 0.0001) compared to untreated diabetic rats. SOD level, however, increased (53.36%; p = 0.0326). These CNME effects were comparable to those in the metformin-treated diabetic rats.ConclusionsC. nutans possesses anti-atherosclerotic properties, which may be due to reductions in vascular tissue oxidative stress, inflammation, and serum AI. Continued studies on atherosclerotic animal models are suggested.  相似文献   
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