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Müllerian inhibiting substance (MIS) is produced by fetal Sertoli cells and causes regression of the Müllerian duct in male fetuses shortly after commitment of the bipotential embryonic gonad to testes differentiation. MIS is also produced by the Sertoli cells and granulosa cells of the adult gonads where it plays an important role in regulating steroidogenesis. We have previously shown that MIS can dramatically reduce testosterone synthesis in Leydig cells by inhibiting the expression of cytochrome P450 17alpha-hydroxylase/C(17-20) lyase (Cyp17) mRNA in vitro and in vivo. To characterize the signal transduction pathway used by MIS to control expression of endogenous Cyp17 in a mouse Leydig cell line, we demonstrate that MIS inhibits both LH- and cAMP-induced expression of Cyp17 at concentrations as low as 3.5 nM and for as long as 18 h. The induction of steroidogenic acute regulatory protein (StAR) mRNA by cAMP, however, was slightly increased by addition of MIS. Protein kinase A (PKA) inhibition with H-89 blocked Cyp17 mRNA induction, suggesting that MIS interferes with the PKA signal transduction pathway. Inhibition of Cyp17 induction was not seen with added U0126, and wortmannin inhibited the induction incompletely. In addition, phosphorylation of the cAMP responsive element binding protein (CREB) was not detected following 50 micro M cAMP exposure, a concentration sufficient for Cyp17 mRNA induction. Moreover, CREB phosphorylation, which was observed with addition of 500 micro M cAMP, was not inhibited by coincubation with MIS. Taken together, these results suggest that cAMP induces expression of Cyp17 by a PKA-mediated mechanism and that this induction, which is inhibited by MIS signal transduction, does not require CREB activity, and is distinct from that used to induce steroidogenic acute regulatory protein expression.  相似文献   
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Background:

This study tested the hypothesis that the low-grade inflammation presented in patients with bipolar disorder (BD) is associated with expansion of activated T cells, and this activated state may be due to a lack of peripheral regulatory cells.

Methods:

Specifically, we investigated the distribution of monocytes and lymphocyte subsets, and investigated Th1/Th2/Th17 cytokines in plasma by flow cytometry. Twenty-one BD type I patients and 21 age- and sex-matched controls were recruited for this study.

Results:

BD patients had increased proportions of monocytes (CD14+). Regarding lymphocyte populations, BD patients presented reduced proportions of T cells (CD3+) and cytotoxic T cells (CD3+CD8+). BD patients also exhibited a higher percentage of activated T CD4+CD25+ cells, and a lower percentage of IL-10 expressing Treg cells.

Conclusions:

Our data shed some light into the underlying mechanisms involved with the chronic low-grade inflammatory profile described in BD patients.  相似文献   
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Metabolic Brain Disease - Acetylcholine is an excitatory neurotransmitter that modulates synaptic plasticity and communication, and it is essential for learning and memory processes. This...  相似文献   
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Strabismus is a pathology that affects approximately 4 % of the population, causing aesthetic problems reversible at any age and irreversible sensory alterations that modify the vision mechanism. The Hirschberg test is one type of examination for detecting this pathology. Computer-aided detection/diagnosis is being used with relative success to aid health professionals. Nevertheless, the routine use of high-tech devices for aiding ophthalmological diagnosis and therapy is not a reality within the subspecialty of strabismus. Thus, this work presents a methodology to aid in diagnosis of syndromic strabismus through digital imaging. Two hundred images belonging to 40 patients previously diagnosed by an specialist were tested. The method was demonstrated to be 88 % accurate in esotropias identification (ET), 100 % for exotropias (XT), 80.33 % for hypertropias (HT), and 83.33 % for hypotropias (HoT). The overall average error was 5.6Δ and 3.83Δ for horizontal and vertical deviations, respectively, against the measures presented by the specialist.  相似文献   
77.
The degree of admixture in Brazil between historically isolated populations is complex and geographically variable. Studies differ as to what the genetic and phenotypic consequences of this mixing have been. In Northeastern Brazil, we enrolled 522 residents of Salvador and 620 of Fortaleza whose distributions of self-declared color were comparable to those in the national census. Using the program Structure and principal components analysis there was a clear correlation between biogeographic ancestry and categories of skin color. This correlation with African ancestry was stronger in Salvador (r=0.585; P<0.001) than in Fortaleza (r=0.236; P<0.001). In Fortaleza, although self-declared blacks had a greater proportion of European ancestry, they had more African ancestry than the other categories. When the populations were analyzed without pseudoancestors, as in some studies, the relationship of ‘race'' to genetic ancestry tended to diffuse or disappear. The inclusion of different African populations also influenced ancestry estimates. The percentage of unlinked ancestry informative markers in linkage disequilibrium, a measure of population structure, was 3–5 times higher in both Brazilian populations than expected by chance. We propose that certain methods, ascertainment bias and population history of the specific populations surveyed can result in failure to demonstrate a correlation between skin color and genetic ancestry. Population structure in Brazil has important implications for genetic studies, but genetic ancestry is irrelevant for how individuals are treated in society, their health, their income or their inclusion. These track more closely with perceived skin color than genetic ancestry.  相似文献   
78.
Objectives: To observe the distribution of patients who presented with low back pain (LBP) and to determine the between therapists’ interrater reliability of assessments in a private outpatient setting using treatment-based classification (TBC) subgroups.

Methods: An observational and methodological study was conducted. Four hundred and twenty-nine patients (231 male; 198 female) presenting LBP symptoms and referred to conservative treatment were assessed by 13 physical therapists who conducted a 60-min examination process utilizing TBC subgroups. Interrater reliability analyses from six raters were assessed using Fleiss’ kappa and previously recorded data (n = 30).

Results: In this study, 65.74% of patients were classified in only one subgroup, the most prevalent being stabilization (21.91%), followed by extension (15.38%), traction (11.89%), flexion (10.96%), manipulation (5.13%), and lateral shift (0.47%). Approximately 20.98% of patients were classified in two subgroups, where the most frequent overlaps were flexion + stabilization (7.46%), extension + stabilization (6.06%), flexion + traction (4.20%), extension + manipulation (1.86%), and 13.29% of patients were not classified in any TBC subgroup. Analysis of interrater reliability showed a kappa value of 0.62 and an overall agreement of 66% between raters.

Discussion: LBP is a heterogeneous clinical condition and several classification methods are proposed in the attempt to observe better outcomes for patients. Eighty-five percent of patients assessed were able to be classified when using the TBC assessment and reliability analysis showed a substantial agreement between raters.

Level of Evidence: 2c.  相似文献   

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