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81.
82.
The behavioral and physiological traits of an individual are strongly influenced by early life events. One of the major systems implicated in the responses to environmental manipulations and stress is the hypothalamus-pituitary-adrenal (HPA) axis. Glucocorticoid hormones (cortisol in humans and corticosterone in rodents) represent the final step in the activation of the HPA system and play an important role in the effects induced by the perinatal environment. We demonstrated, in rats with some differences between males and females, that mothers whose drinking water was supplemented with moderate doses of corticosterone throughout the lactation period, give birth to offspring better able to meet the demands of the environment. The progeny of these mothers, as adults, show improved learning capabilities, reduced fearfulness in anxiogenic situations, lower metabotropic glutamate receptors and higher glucocorticoid receptors in the hippocampus with a persistent hyporeactivity of the HPA axis leading to a resistance to ischemic neuronal damage. Other studies performed in mice showed that low doses of corticosterone in the maternal drinking water, which, as in our rat model, may reflect a form of mild environmental stimulation, enhanced the offspring's ability to cope with different situations, while elevated doses, comparable to those elicited by strong stressors, caused developmental disruption. Significantly, adult rats and mice that had been nursed by mothers with a mild hypercorticosteronemia provide an example of how a moderate corticosterone increase mediates the salutary effects of some events occurring early in life. Both maternal and infantile plasma levels of the hormone may play a role in these effects, the first influencing maternal behavior, the second acting directly on the central nervous system of the developing rat.  相似文献   
83.
Various infectious agents, such as Toxoplasma gondii, have been hypothesized to be potentially relevant etiological factors in the onset of some cases of schizophrenia. We conducted a randomized, double-blind, placebo-controlled treatment trial in an attempt to explore the hypothesis that the symptoms of schizophrenia may be related to infection of the central nervous system with toxoplasma gondii. Systematically selected patients with ongoing and at least moderately severe schizophrenia from Butajira, in rural Ethiopia, were randomly allocated to trimethoprim or placebo, which were added on to participants'' regular antipsychotic treatments. Trial treatments were given for 6 months. The Positive and Negative Syndrome Scale (PANSS) was used to assess outcome. Ninety-one patients were included in the study, with 80 cases (87.9%) positive for T. gondii immunoglobulin G antibody. Seventy-nine subjects (87.0%) completed the trial. The mean age of subjects was 35.3 (SD = 8.0) years, with a mean duration of illness of 13.2 (SD = 6.7) years. Both treatment groups showed significant reduction in the overall PANSS score with no significant between-group difference. In this sample of patients with chronic schizophrenia, trimethoprim used as adjuvant treatment is not superior to placebo. However, it is not possible to draw firm conclusion regarding the etiological role of toxoplasmosis on schizophrenia based on this study because the timing and the postulated mechanisms through which toxoplasmosis produces schizophrenia are variable.  相似文献   
84.
This report describes the utility of antigens prepared from different coccoid and spiral forms of Helicobacter pylori in a serological method. The presence of IgM antibody to H. pylori was determined in 22 human sera on antigens prepared from 24 strains of H. pylori. Antigens prepared from spiral form of certain strains of H. pylori detected IgM in all confirmed positive sera. Antigens obtained from the coccoid cells of the same strains could not completely detect IgM in the same sera. Testing sera on boosted antigens of the coccoid cells showed reduction in the number of false negative, indicating that the coccoid cells do not have one or more antigenic fractions essential for accurate detection of antibody. Our data suggest that H. pylori may lose CagA during the coccoid conversion process and regain it in the spiral form. In conclusion, we suggest that the antigen used for the detection of antibodies to H. pylori in serological methods should contain a broad spectrum of antigenic fractions and should be prepared from certain strains and culturable cells of H. pylori.  相似文献   
85.
Necrotizing (malignant) external otitis (NEO) is an infection involving the temporal and the adjacent bones. It is a rare type of external otitis that occurs primarily in immunocompromised persons. The present study aimed to evaluate its management and outcome in recurrent cases. Ten patients attending the ENT Department, Alexandria University were included. They had recurrence of otitis externa over a period of 6 months after-cure, as well as severe night otalgia and high ESR level. Peri-auricular soft tissue swelling, cranial nerve paralysis and trismus were the main persistent or developing presentations in recurrent cases. Extensive surgical intervention was performed in four patients with unsatisfactory outcome. On the other hand, satisfactory results were obtained with those treated with specific medical therapy after culture and sensitivity test and those who underwent minimal surgical intervention. In conclusion, NEO is an aggressive disease that necessitates conservative management and local debridement of sequestrated tissues. The ESR is a good indicator of treatment response. It is recommended to be meticulous in treatment of cases with recurrent NEO and extensive surgical interventions are discouraged.  相似文献   
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87.
The myelin‐associated protein Nogo‐A contributes to the failure of axon regeneration in the mammalian central nervous system (CNS). Inhibition of axon growth by Nogo‐A is mediated by the Nogo‐66 receptor (NgR). Nonmammalian vertebrates, however, are capable of spontaneous CNS axon regeneration, and we have shown that retinal ganglion cell (RGC) axons regenerate in the lizard Gallotia galloti. Using immunohistochemistry, we observed spatiotemporal regulation of Nogo‐A and NgR in cell bodies and axons of RGCs during ontogeny. In the adult lizard, expression of Nogo‐A was associated with myelinated axon tracts and upregulated in oligodendrocytes during RGC axon regeneration. NgR became upregulated in RGCs following optic nerve injury. In in vitro studies, Nogo‐A‐Fc failed to inhibit growth of lizard RGC axons. The inhibitor of protein kinase A (pkA) activity KT5720 blocked growth of lizard RGC axons on substrates of Nogo‐A‐Fc, but not laminin. On patterned substrates of Nogo‐A‐Fc, KT5720 caused restriction of axon growth to areas devoid of Nogo‐A‐Fc. Levels of cyclic adenosine monophosphate (cAMP) were elevated over sustained periods in lizard RGCs following optic nerve lesion. We conclude that Nogo‐A and NgR are expressed in a mammalian‐like pattern and are upregulated following optic nerve injury, but the presence of Nogo‐A does not inhibit RGC axon regeneration in the lizard visual pathway. The results of outgrowth assays suggest that outgrowth‐promoting substrates and activation of the cAMP/pkA signaling pathway play a key role in spontaneous lizard retinal axon regeneration in the presence of Nogo‐A. Restriction of axon growth by patterned Nogo‐A‐Fc substrates suggests that Nogo‐A may contribute to axon guidance in the lizard visual system. J. Comp. Neurol. 525:936–954, 2017. © 2016 Wiley Periodicals, Inc.  相似文献   
88.
AIM: To identify patients with or without liver steatosis and its severity in treatment-na?ve patients affected by hepatitis C virus(HCV) infection.METHODS: We included 56 HCV infected patients, and assessed the amount of liver fat by histomorphometry, and its relationships with fat and lean mass at different parts of the body(by densitometry), hormones [insulin, homeostatic model assessment(HOMA)], adipokines(resistin, adiponectin, leptin), and cytokines(tumor necrosis factor α, interleukin-6).RESULTS: Although the intensity of liver steatosis is related to trunk fat mass and HOMA, 33% of patients showed no liver steatosis, and this finding was not related to body mass index or genotype. Besides trunkfat mass, no other factor was related to the presence or not of liver steatosis, or to the intensity of it, by multivariate analysis. Lean mass was not related to liver steatosis. Adiponectin levels were lower among patients. No differences were observed in leptin and resistin.CONCLUSION: Steatosis in HCV infection is common(67.2%), and closely related to trunk fat, and insulin resistance, but not with leg fat mass or adipokines.  相似文献   
89.
Major depression is a common, recurrent, and chronic disease that negatively affects the quality of life and increases the risk of mortality. Several studies have demonstrated that curcumin, the yellow‐pigmented substance of the turmeric, possesses antidepressant properties. The aim of this review is to meta‐analytically assess the antidepressant effect of curcumin in patients with major depressive disorders. We extensively searched the literature until August 2015. The random‐effect model was used to calculate the pooled standardized difference of means (SMD). Subgroup analyses were also performed to examine the effect of different study characteristics on the overall model. Six clinical trials met the inclusion criteria. Overall, curcumin administration showed a significantly higher reduction in depression symptoms [SMD = ?0.34; 95% confidence interval (CI) = ?0.56, ?0.13; p = 0.002]. Subgroup analyses showed that curcumin had the highest effect when given to middle‐aged patients (SMD = ?0.36; 95% CI = ?0.59; ?0.13; p = 0.002), for longer duration of administration (SMD = ?0.40; 95% CI = ?0.64, ?0.16; p = 0.001), and at higher doses (SMD = ?0.36; 95% CI = ?0.59, ?0.13; p = 0.002). The administration of new formulation of curcumin (BCM‐95) had non‐significantly higher effect on depression as compared with the conventional curcumin–piperine formula. We conclude that there is supporting evidence that curcumin administration reduces depressive symptoms in patients with major depression. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
90.
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