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BACKGROUND: Dehydroepiandrosterone (DHEA) is among the most abundant steroids in the human body and appears to have diverse biochemical activities. This multifunctional hormone has long been a compound of interest to research psychiatrists. Its recent promotion and availability as an over-the-counter supplement to the general public has led to widespread use. Little is known about potential adverse effects of DHEA when consumed on an acute or chronic basis. We report a case of mania in an older man acutely admitted to our psychiatric facility with no previous personal or family history of bipolar disorder that appeared to be related to recent DHEA use. The patient had initiated DHEA use 6 months prior to admission and was taking 200-300 mg/day at the time of presentation. METHODS: He was treated with valproic acid 500 mg twice daily. RESULTS: The patient showed sufficient improvement to be discharged following a 7-day inpatient hospitalization. CONCLUSIONS: A wide range of medications have been associated with the induction of hypomania and mania, and we have provided a brief discussion of the potential for DHEA to trigger manic symptoms.  相似文献   
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Immunocytochemical examination for mitochondrial protein and cytochrome oxidase was performed to demonstrate oncocytes in normal adenohypophysis obtained from 28 patients of various age. A small number of solitary large epithelial cells showed intense cytoplasmic granular immunoreactivities for mitochondrial protein and cytochrome oxidase. The proportions of the cells positive for the former and the latter ranged from 0% to 5.9% (mean+/-SD; 1.5+/-1.7%) and from 0% to 4.9% (1.4+/-1.6%), respectively. These cells were either absent or extremely rare in young patients (under 10 years) but tended to increase in number with age (P < 0.0001). On the other hand, the mirror section technique showed that most of these cells were negative for adenohypophysial hormones, but a few of them were faintly positive for: alpha-subunit (8.0%), beta-subunits of follicle-stimulating hormone (4.8%), luteinizing hormone (2.5%), thyroid-stimulating hormone (1.0%), and growth hormone (0.5%), and were negative for prolactin and adrenocorticotropic hormone. We considered that these cells represent oncocytes that exist in varying numbers in normal adenohypophysis. It was suggested that oncocytes in normal adenohypophysis share various common features with tumorous oncocytes of pituitary oncocytomas.  相似文献   
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In only three chemical operations, natural trioxane lactone artemisinin (1) was converted into a series of C-10 carbon-substituted 10-deoxoartemisinin compounds 4-9. The three steps involved lactone reduction, replacement of the anomeric lactol OH by F using diethylaminosulfur trifluoride, and finally boron trifluoride-promoted substitution of F by aryl, heteroaryl, and acetylide nucleophiles. All of these C-10 nonacetal, chemically robust, enantiomerically pure compounds 4-9 have high antimalarial potencies in vitro against Plasmodium falciparum malaria parasites, and furans 5a and 5b and pyrrole 7a are antimalarially potent also in vivo even when administered to rodents orally.  相似文献   
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A series of 2-amino-3-substituted-6-[(E)-1-phenyl-2-(N-methylcarbamoyl)vinyl]+ ++imid azo[1,2-a]pyridines 1a-i, structurally related to Enviroxime and its analogous benzimidazoles, was designed and prepared for testing as antirhinovirus agents. The imidazo ring in this class of compounds was constructed starting from the aminopyridine after tosylation and subsequent treatment with the appropriate acetamides. The key steps in the synthesis include the development and use of a new Horner-Emmons reagent for the direct incorporation of methyl vinylcarboxamide. The reaction was stereospecific in the substrates 5a-f leading exclusively to the desired E-isomer and avoiding the use of reverse-phase preparative HPLC for the separation of both possible isomers before antiviral activity evaluation. The isopropylsulfonyl group, known as the best substituent at the 1-position in the benzimidazole SAR in terms of activity, was introduced in this new series of imidazo[1,2-a]pyridines via halogen-metal exchange and subsequent treatment with isopropyl isopropanethiolsulfonate. Compounds 1a-i were evaluated in plaque reduction assay and in a cytopathic effect assay. Compounds 1b-d,h exhibited a strong antirhinovirus activity, and no apparent cellular toxicity was visible. The substitution at the 3-position was required for activity. Surprisingly the isopropylsulfonyl in this family of compounds did not enhance the activity as in the case of benzimidazoles. Instead, compound 1i was 4 times less active than its phenyl and sulfide partners. The chemistry as well as the biological evaluation are discussed.  相似文献   
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Two soybean cDNA clones, SPK-3 and SPK-4, encoding putative protein kinases were isolated and characterized. Both cDNAs encoded approximately 40-kDa serine/threonine kinases with unusual stretches of acidic amino acids in their carboxy-terminal regions, which are highly homologous to PKABA1 from wheat and ASKs from Arabidopsis. These kinases are encoded by one- or two-copy genes in the soybean genome. Notably, SPK-3 and -4 showed different patterns of expression in various soybean tissues. SPK-3 is highly expressed in dividing and elongating tissues of young seedlings but relatively weakly in tissues of mature plants. In contrast, SPK-4 showed relatively high and constitutive expression in all the tissues examined except for leaf tissues of mature plants. Although various stressors, such as dehydration and high salinity, increased the expression of both genes, the induction kinetics were different. The two genes also differed in their response to abscisic acid (ABA). SPK-3 was induced but SPK-4 was not affected by exogenously supplied abscisic acid. In accordance with these expression data analysis of the activity of a chimeric SPK-3 promoter::beta-glucuronidase (GUS) reporter gene by transient expression in tobacco leaves confirmed the inducibility of SPK-3 by salt and ABA. Polyclonal antibodies raised against a recombinant SPK-4 protein produced in Escherichia coli specifically recognized both recombinant SPK-3 and -4 proteins. Kinase assays using affinity-purified SPK-4/ antibody complexes with crude soybean extracts as substrate identified specific phosphorylation of two 41 and 170 kDa soybean proteins that were phosphorylated on serine residues. Taken together, our results suggest that SPK-3, and/or SPK-4 are functional serine protein kinase(s). Furthermore, SPK-3 and -4 may play different roles in the transduction of various environmental stresses.  相似文献   
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