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991.
Levels of pyruvate and alpha-ketoglutarate in the cerebrospinal fluid (CSF) of 26 children, aged 4 months to 5 1/2 years, with febrile seizures and of 19 children, aged 4 months to 14 years, with the diagnosis of epilepsy were not different from values seen in 119 "normal" children 8 days to 14 years of age. The CSF samples from 24 adults, 24 to 81 years of age, suspected of having a herniated disk were also examined. In the pediatric age group, the data showed a highly significant downward trend of CSF and plasma alpha-ketoglutarate values with age; pyruvate values did not change. A correlation of the values of the two keto acids in the blood and CSF of 42 other children without apparent neurologic disease was also made. Findings in a child with thiamine deficiency suggest that CSF alpha-ketoglutarate may be a more sensitive indicator of deficiency than plasma alpha-ketoglutarate or pyruvate. Measurements of these keto acids in plasma and CSF may be diagnostically useful in a variety of metabolic disorders. Findings in 155 children from birth (20 minutes) to 17 years of age without neurologic disease are submitted as a standard of reference.  相似文献   
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The regulation of the dopamine (DA) receptors is of considerable interest, in part because treatment with antipsychotic drugs is known to upregulate striatal D2-like receptors. While previous studies have focused on the regulation of striatal DA receptors, less is known about the pharmacological regulation of cortical DA receptors. The purpose of this study was to examine the regulation of DA mRNA receptor expression in the cortex compared to the striatum following treatment with antipsychotic agents. Adult male Sprague-Dawley rats were injected daily with haloperidol (2 mg/kg/day), clozapine (20 mg/kg/day) or a control vehicle for a period of 14 days. Following treatment, brains were subjected to in situ hybridization for the mRNAs encoding the five dopamine receptors; only D1, D2, and D3 receptor mRNAs were detected in these regions. Haloperidol tended to either modestly upregulate or have no effect on dopamine receptor mRNAs detected in striatal structures, while clozapine generally downregulated these mRNAs. On the other hand, in the cortex, both drugs had striking effects on D1 and D2 mRNA levels. Cortical D1 mRNA was upregulated by haloperidol, but this effect was primarily restricted to cingulate cortex; clozapine also upregulated D1 mRNA, but primarily in parietal regions. Haloperidol downregulated D2 mRNA in the majority of cortical regions, but most dramatically in frontal and cingulate regions; clozapine typically upregulated this mRNA, but primarily in regions other than frontal and cingulate cortex. These results indicate that clozapine and haloperidol each have regionally-specific effects, and differentially regulate dopamine receptor mRNA expression in striatal and cortical regions of the rat brain.  相似文献   
996.
The authors have briefly discussed the molecular structure, regulation, and function of progesterone receptors in the mammalian ovary. Particularly important is the contrast in the regulatory mechanisms of PR induction in the ovary (gonadotropins/membrane receptor mediated) and other well-known progesterone target tissues, such as the uterus and mammary gland (estrogen/nuclear receptor mediated). Future research will focus on how the PR gene responds to these hormonal regulatory signals in this cell-specific manner. Equally important in this discussion has been the mounting evidence indicating that PRs are an essential component of the ovulatory process. The observation that PR-/- knockout mice are incapable of undergoing ovulation, even in response to gonadotropin challenge, further supports the previous physiological evidence indicating that PRs in preovulatory follicles are induced before, and are necessary for, ovulation. Further studies are required to determine the identity of PR-regulated target genes during the periovulatory period. Although our knowledge of PR structure, regulation, and function has increased dramatically during the past decade, many exciting questions remain related to the regulation and function(s) of PRs in the ovary and other tissues.  相似文献   
997.

Background  

The primary objective was to determine whether consumption of conjugated linoleic acids (CLAs) affected the fecal microbiota composition, fecal enzyme activity or fecal composition.  相似文献   
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Monoclonal antibodies (MoAbs) that selectively identify Muc-1 core protein (MoAbs DF3-P, VU-4H5) determinants were used to identify the Muc-1 glycoform present on 7 multiple myeloma (MM) cell lines, 5 MM patient plasma cells, 12 MM patient B cells, as well as 32 non-MM cell lines and normal hematopoietic cells. Flow cytometry studies demonstrated that all MM cell lines, MM patient plasma cells, and MM patient B cells expressed Muc-1 core protein epitopes. Circulating B cells from 4 normal donors also expressed Muc-1 core protein. In contrast, Muc-1 core protein was absent on 28 of 32 non-MM neoplastic cell lines, 17 of which expressed Muc-1. Splenic and tonsillar B cells, CD34(+) stem cells, resting T cells, and bone marrow plasma cells obtained from normal donors both lacked Muc-1 glycoforms. We next studied the effects of estrogen, progesterone, and glucocorticoid receptor agonists and antagonists on Muc-1 expression, because consensus sequences for the response elements of these steroids are present on the Muc-1 gene promoter. These studies showed that dexamethasone (Dex) induced Muc-1 expression on MM cell lines, as determined by both flow cytometry and Western blot analyses. Dex also induced upregulation of Muc-1 on prostate and ovarian cancer cell lines. Time and dose-response studies demonstrated that Dex induced maximal cell surface Muc-1 expression by 24 hours at concentrations of 10(-8) mol/L. Dex induced Muc-1 upregulation could be blocked with a 10-fold excess of the glucocorticoid receptor antagonist RU486, confirming that Dex was acting via the glucocorticoid receptor. No changes in Muc-1 expression were observed on MM cells treated with estrogen and progesterone receptor agonists and antagonists or with RU486. These studies provide the framework for targeting Muc-1 core protein in vaccination and serotherapy trials in MM. In addition, the finding that Muc-1 expression on MM cells can be augmented by Dex at pharmacologically achievable levels suggests their potential utility in enhancing treatments targeting Muc-1 in MM.  相似文献   
999.
In contrast to organic anions, substrates for the canalicular mdr1a and b are usually organic cations and are often sequestered in high concentrations in intracellular acidic compartments. Because many of these compounds are therapeutic agents, we investigated if their sequestration could be regulated. We used isolated perfused rat liver (IPRL), isolated rat hepatocyte couplets (IRHC), and WIF-B cells to study the cellular localization and biliary excretion of the fluorescent cation, daunorubicin (DNR). Despite rapid (within 15 minutes) and efficient (>90%) cellular uptake in the IPRL, only approximately 10% of the dose administered (0.2-20 micromol) was excreted in bile after 85 minutes. Confocal microscopy revealed fluorescence predominantly in vesicles in the pericanalicular region in IPRL, IRHC, and WIF-B cells. Treatment of these cells with chloroquine and bafilomycin A, agents that disrupt the pH gradient across the vesicular membrane, resulted in a loss of vesicular fluorescence, reversible in the case of bafilomycin A. Taurocholate (TC) and dibutyryl cAMP (DBcAMP), stimulators of transcytotic vesicular transport, increased the biliary recovery of DNR significantly above controls, by 70% and 35%, respectively. The microtubule destabilizer, nocodazole, decreased biliary excretion of DNR. No effect on secretion was noted in TR- mutant rats deficient in mrp2. Coadministration of verapamil, an inhibitor of mdr1, also decreased DNR excretion. While TC and DBcAMP did not affect the fluorescent intensity or pattern of distribution in IRHC, nocodazole resulted in redistribution of DNR to peripheral punctuate structures. These findings suggest that the organic cation, DNR, is largely sequestered in cells such as hepatocytes, yet its excretion can still be modulated.  相似文献   
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