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41.
AIDS and Behavior - Injection drug use has been the leading route of HIV transmission in Iran. We assessed HIV prevalence, risk behaviors, and uptake of prevention services among people who inject...  相似文献   
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Prostate cancer is a serious threat to men's health, so it is necessary to develop the techniques for early detection of this malignancy. Radiolabeled peptides are the useful tools for diagnosis of prostate cancer. In this research, we designed a new HYNIC‐conjugated GnRH analogue and labeled it by 99mTc with tricine/EDDA as coligands. We used aminohexanoic acid (Ahx) as a hydrocarbon linker to generate 99mTc‐(tricine/EDDA)‐HYNIC‐Ahx‐[DLys6]GnRH. The radiopeptide exhibited high radiochemical purity and stability in solution and serum. Two human prostate cancer cell lines LN‐CaP and DU‐145 were used for cellular experiments. The binding specificity and affinity of radiopeptide for LN‐CaP were superior to DU‐145 cells. The Kd values for LN‐CaP and DU‐145 cells were 41.91 ± 7.03 nM and 55.96 ± 10.56 nM, respectively. High kidney uptake proved that the main excretion route of radiopeptide was through the urinary system. The tumor/muscle ratio of 99mTc‐HYNIC‐Ahx‐[DLys6]GnRH was 4.14 at 1 hr p.i. that decreased to 2.41 at 4 hr p.i. in LN‐CaP tumor‐xenografted nude mice. The blocking experiment revealed that the tumor uptake was receptor‐mediated. The lesion was visualized clearly using 99mTc‐[DLys6]GnRH at 1 hr p.i. Accordingly, this research highlights the capability of 99mTc‐(tricine/EDDA)‐HYNIC‐Ahx‐[DLys6]GnRH peptide as a promising agent for GnRHR‐expressing tumor imaging.  相似文献   
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Objectives/BackgroundMedical therapy is the first line of treatment for intracranial atherosclerotic disease (ICAD). Percutaneous transluminal angioplasty and stenting (PTAS) are mainly considered for those patients with severe stenosis and recurrent events despite aggressive medical therapy. In this review, we discuss the application of PTAS as a treatment option for ICAD and its future prospect.Materials and MethodsWe did the literature review of the key articles and guidelines to elaborate on the role of PTAS in the management of ICAD based on the current data and expert opinion. We searched PubMed, Google Scholar, and Scopus up to August 2020, and included articles published only in the English language.ResultsSince the publication of the results from SAMMPRIS and VISSIT trials, stenting is no longer recommended for secondary stroke prevention in patients with symptomatic ICAD. However, recent clinical studies on intracranial stenting for a subgroup of ICAD patients have shown promising results, likely due to better patient selection and continued advancement of endovascular techniques.ConclusionThere exists a lack of consensus regarding the best endovascular treatment approach (e.g., angioplasty alone or balloon mounted stent vs. self-expanding stent with or without prior angioplasty) or management of in-stent restenosis. Another area of clinical controversy relates to the ideal use and duration of antiplatelet therapy.  相似文献   
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Aging is an unavoidable fate that afflicts all life, during this process in mammals reactive oxygen species (ROS) are generated which stimulate tyrosinase, elastase and collagenase activities that actively participate in skin aging. Therefore, the maintenance of antioxidant homeostasis is an important anti-aging strategy for skin. Nature has excellent anti-aging remedies that act externally as well as internally to delay the visual signs of aging. In view of this fact, the present study investigates the in vitro anti-aging activity of five medicinal plants belonging to phenolic rich families namely Rosmarinus officinalis, Lavandula officinalis, Matricaria chamomilla, Camellia sinensis and Pelargonium graveolens. The selected plants are those most frequently used in the preparation of ethnomedicinal recipes for the prevention or treatment of aging. The inhibitory effects of the ethanolic and aqueous extracts of the five selected plants on the activity of tyrosinase, elastase, and collagenase enzymes were investigated. Furthermore, the chemical composition of the plants and the antioxidant capacity of their extracts were assessed. The results showed that R. officinalis had the highest total phenolics content which was correlated with its potent antioxidant and anti-aging activities. To pinpoint the active metabolites in the tested extracts, we evaluated the metabolite variations using ultra-performance liquid chromatography coupled with high resolution electrospray ionization-tandem mass spectrometry (UPLC-HR-ESI-MS/MS). Multivariate data analysis (MVDA) revealed that R. officinalis significantly accumulated metabolites from the aromatic diterpenoid, flavonoid and phenolic acid classes. These results indicate that rosemary can be used for further development of topical preparations with anti-aging properties.

Aging is an unavoidable fate that afflicts all life, during this process in mammals, reactive oxygen species (ROS) are generated which stimulate tyrosinase, elastase and collagenase activities that actively participate in skin aging.  相似文献   
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This study aimed to assess glutathione‐S–transferase (GST) enzyme‐ oxidative stress (OS) relationship in the internal spermatic vein (ISV) of infertile men associated with varicocele (Vx). Ninety five infertile oligoasthenoteratozoospemic (OAT) men associated with Vx were subjected to history taking, clinical examination and semen analysis. During inguinal varicocelectomy, GST, malondialdehyde (MDA) and glutathione peroxidase (GPx) were estimated in the blood samples drawn from ISV and median cubital veins. The mean levels of GST, GPx were significantly decreased and the mean level of GPx was significantly increased in the ISV compared with the peripheral blood. The mean level of GST and GPx in the ISV was significantly decreased, and the mean level of MDA was significantly increased in Vx grade III compared with Vx grade II cases. There was nonsignificant difference in the mean level of GST in the ISV in unilateral Vx cases compared with bilateral Vx cases. There was significant positive correlation of GST with sperm count, sperm motility, GPx and significant negative correlation with sperm abnormal forms, MDA. It is concluded that ISV of infertile men associated with Vx has decreased levels of GST compared with peripheral venous circulation that is correlated with both OS and Vx grade.  相似文献   
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Rats repeatedly intoxicated with alcohol (ethanol, three times daily) over a 4-day period display neuronal degeneration in the dentate gyrus; entorhinal, piriform, insular, orbital, and perirhinal cortices; and in the olfactory nerve fibers and terminals in the olfactory bulb. Postulating a role for excitotoxicity, we have attempted to prevent the degeneration using antagonists that are neuroprotective in this type of brain damage. In an initial study, continuous subcutaneous infusion of a high dose of the glutamate/NMDA receptor antagonist MK-801 (2 mg/kg/day) by itself caused extensive neuronal degeneration in several brain regions and severe behavioral intoxication that precluded survival if combined with high blood alcohol levels (~300 mg/dl). Moreover, the lower, nonneurotoxic blood alcohol levels (~150 mg/dl) that were compatible with survival worsened the MK-801-induced brain damage. In a subsequent experiment, daily intraperitoneal injections of a lower dose of MK-801 (1 mg/kg/day) resulted in no MK-801 toxicity and, when combined with neurotoxic levels of alcohol, no reduction in alcohol-induced neurotoxicity. Nimodipine, a voltage-gated Ca2+ channel blocker, reduced the neuronal damage in the dentate gyrus, but greatly increased it in the piriform cortex when administered intragastrically at 600 mg/kg/day; it provided no protection from alcohol-dependent degeneration when given intragastrically at 100 mg/kg/day. Continuous intracere-broventricular delivery of 0.24 to 0.29 mg/day of 6,7-dinitro-quinoxa-line-2,3-dione, a glutamate/α-amino-3-hydroxy-5-methyl-4-isoxazole receptor antagonist, failed to diminish alcohol-dependent neuronal damage in any brain region. We conclude that brain damage from episodic “binge” alcohol intoxication is not primarily mediated by excitotoxic mechanisms, implying that other, nonexcrtotoxic pathophysiological mechanisms, are involved. Furthermore, MK-801, far from protecting from the alcohol-induced damage, at high doses causes widespread neuropathology that is significantly potentiated by alcohol.  相似文献   
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