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41.
BACKGROUND: We previously reported that the level of interleukin (IL)-6 is increased in the peritoneal fluid of women with endometriosis. This study was undertaken to assess the effects of IL-6 and soluble IL-6 receptor (sIL-6R) on in vitro sperm motility. METHODS: Sperm (n = 20) were cultured with IL-6 or sIL-6R, or with a combination of both. After 24 h cultures, sperm motility was evaluated using a computer-assisted semen analysis system. Gene and protein expressions of IL-6, IL-6 receptor (IL-6R), and glycoprotein 130 (gp130) were examined in sperm by RT-PCR analysis and western blot analysis. RESULTS: Addition of IL-6 or sIL-6R individually to the culture media had no affect on sperm motion. However, adding a combination of IL-6 and sIL-6R dose-dependently reduced the percentage of motile and rapidly moving sperm. Adding anti-IL-6R antibody abolished these adverse effects. Sperm expressed the gp130 gene and protein, but not IL-6 or IL-6R. CONCLUSIONS: A combination of IL-6 and sIL-6R may be associated with gp130 expressed in the sperm and reduce sperm motility. IL-6 and sIL-6R may contribute to the pathogenesis of endometriosis-associated infertility.  相似文献   
42.
Serotonin (5-HT) has been a candidate for neurotransmitters in cutaneous type I mechanoreceptors (i.e., Merkel cell-nerve endings). Although recent electrophysiological studies have suggested the presence of the 5-HT2 and 3 receptors in the Merkel cell-nerve endings, the histological localization of these receptors are obscure. We thus immunohistochemically examined the presence of 5-HT1, 2, 3 receptors in Merkel cell-nerve endings in sinus hair follicles of the rat whisker pad. We also studied the immunohistochemical localization of the 5-HT transporter to confirm the site of 5-HT secretion. For this purpose, we used antibodies for the 5-HT1A, 5-HT1B, 5-HT2A, 5-HT2C and 5-HT3 receptors, and for the 5-HT transporter, as well as antibodies for cytokeratin 20 (as a marker of Merkel cells) and neurofilament H (a marker of type I sensory nerve terminals). The immuno-stained sections were analyzed under a laser-scanning microscope. It was found that the sensory nerve terminals in the Merkel cell-nerve endings showed strong positive immunoreactions of 5-HT1A and 1B receptors but not 5-HT2A, 2C, and 3 receptors. Furthermore, both the Merkel cells and related axon terminals showed strong immunoreactions of the 5-HT transporter. These findings support the idea that 5-HT molecules are released from the Merkel cells during mechanical reception and indirectly regulate neural actions of sensory neurons via 5-HT1 receptors. The localization of the 5-HT transporter found in this study also suggests a possibility that axon terminals in the Merkel cell-nerve endings also release 5-HT.  相似文献   
43.
The gene Bcl11b, which encodes zinc finger proteins, and its paralog, Bcl11a, are associated with immune-system malignancies. We have generated Bcl11b-deficient mice that show a block at the CD4-CD8- double-negative stage of thymocyte development without any impairment in cells of B- or gammadelta T cell lineages. The Bcl11b-/- thymocytes showed unsuccessful recombination of V(beta) to D(beta) and lacked the pre-T cell receptor (TCR) complex on the cell surface, owing to the absence of Tcrb mRNA expression. In addition, we saw profound apoptosis in the thymus of neonatal Bcl11b-/- mice. These results suggest that Bcl11b is a key regulator of both differentiation and survival during thymocyte development.  相似文献   
44.
Corneal epithelial lesions distinguish vernal keratoconjunctivitis (VKC) from other ocular allergic diseases. Such lesions result from degradation of the corneal epithelial basement membrane, which comprises mostly type IV collagen and laminin. Matrix metalloproteinase 2 (MMP-2) and MMP-9 catalyze the degradation of these 2 extracellular matrix proteins. The possible role of MMP-2 and MMP-9 in the pathogenesis of corneal lesions associated with VKC was investigated by assaying tear fluid for the presence of these enzymes. Tear fluid was collected from 6 eyes of 6 patients with active VKC, 14 eyes of 14 patients with active allergic conjunctivitis, and 6 eyes of 6 nonallergic healthy volunteers. Gelatin zymography revealed that the tear fluid of healthy volunteers contained inactive proforms of both MMP-2 and MMP-9 but not the active forms of these enzymes. Active forms of MMP-2 or MMP-9 were detected in a minority of patients with allergic conjunctivitis. However, with the exception of one individual for whom active MMP-9 was not detected, tear fluid from all patients with VKC contained both proforms and active forms of MMP-2 and MMP-9. These results implicate MMP-2 and MMP-9 in the pathogenesis of corneal epithelial disorders associated with VKC.  相似文献   
45.
An autopsy case of pulmonary candidiasis occurring in a neonatal girl was reported. The mycological examination of the lung taken at autopsy revealed only Candida albicans and followed by the elucidation under the microscopic sections prepared with special stains; periodic acid-Schiff and methenamine silver, in the lung, stomach, umbilical cord, and amnion. The presence of Candida vaginitis in her mother supported the concept that Candida albicans was the etiological agent of the pulmonary candidiasis.  相似文献   
46.
After receiving information from afferent nerves, the hypothalamus sends signals to peripheral organs, including the liver, to keep homeostasis. There are two ways for the hypothalamus to signal to the peripheral organs: by stimulating the autonomic nerves and by releasing hormones from the pituitary gland. In order to reveal the involvement of the autonomic nervous system in liver function, we focus in this study on autonomic nerves and neuroendocrine connections between the hypothalamus and the liver. The hypothalamus consists of three major areas: lateral, medial, and periventricular. Each area has some nuclei. There are two important nuclei and one area in the hypothalamus that send out the neural autonomic information to the peripheral organs: the ventromedial hypothalamic nucleus (VMH) in the medial area, the lateral hypothalamic area (LHA), and the periventricular hypothalamic nucleus (PVN) in the periventricular area. VMH sends sympathetic signals to the liver via the celiac ganglia, the LHA sends parasympathetic signals to the liver via the vagal nerve, and the PVN integrates information from other areas of the hypothalamus and sends both autonomic signals to the liver. As for the afferent nerves, there are two pathways: a vagal afferent and a dorsal afferent nerve pathway. Vagal afferent nerves are thought to play a role as sensors in the peripheral organs and to send signals to the brain, including the hypothalamus, via nodosa ganglia of the vagal nerve. On the other hand, dorsal afferent nerves are primary sensory nerves that send signals to the brain via lower thoracic dorsal root ganglia. In the liver, many nerves contain classical neurotransmitters (noradrenaline and acetylcholine) and neuropeptides (substance P, calcitonin gene-related peptide, neuropeptide Y, vasoactive intestinal polypeptide, somatostatin, glucagon, glucagon-like peptide, neurotensin, serotonin, and galanin). Their distribution in the liver is species-dependent. Some of these nerves are thought to be involved in the regulation of hepatic function as well as of hemodynamics. In addition to direct neural connections, the hypothalamus can affect metabolic functions by neuroendocrine connections: the hypothalamus-pancreas axis, the hypothalamus-adrenal axis, and the hypothalamus-pituitary axis. In the hypothalamus-pancreas axis, autonomic nerves release glucagon and insulin, which directly enter the liver and affect liver metabolism. In the hypothalamus-adrenal axis, autonomic nerves release catecholamines such as adrenaline and noradrenaline from the adrenal medulla, which also affects liver metabolism. In the hypothalamus-pituitary axis, release of glucocorticoids and thyroid hormones is stimulated by pituitary hormones. Both groups of hormones modulate hepatic metabolism. Taken together, the hypothalamus controls liver functions by neural and neuroendocrine connections.  相似文献   
47.
After approximately one and a half decades of intensive studies, the exact mechanisms to explain HIV-mediated cytopathicity are still enigmatic and need closer scrutiny. There has been a dichotomy between virological and immunological viewpoints in understanding HIV-mediated cytopathicity, the former emphasizing a killing of infected cells by HIV-1 and the latter emphasizing indirect mechanisms wherein HIV or its soluble component(s) alter CD4 T-cell function and induce susceptibility to apoptosis. Accumulating evidence points to the notion that apoptosis might be a major contributor to the depletion of CD4 T-cells in HIV infection. This review summarizes current information about the regulatory mechanisms of T-cell apoptosis and the role of apoptosis in HIV pathogenesis with the goal of providing an integrated view of HIV cytopathicity.  相似文献   
48.
Abnormal spontaneous firing of primary sensory neurons is considered to be a cause of neuropathic pain. However, pathogenic mechanisms of hyperexcitable sensory neurons in neuropathic model animals are unclear. We examined effects of chronic treatment of nerve growth factor (NGF), one of candidate mediators for the pathogenesis, on excitability of sensory neurons by voltage-clamped recording in a cell-attached configuration. From rat dorsal root ganglion (DRG) neurons cultured without NGF, only stable holding currents without spontaneous firing activity were recorded. On the other hand, more than 20% neurons cultured in the presence of NGF for more than 3 days showed spontaneous current spikes at frequencies between 0.1 and 5 Hz. Each spikes had an initial inward phase followed by the outward phase, resulted from spontaneous transient depolarization followed by transient hyperpolarization. These spontaneous spikes were abolished by tetrodotoxin, lidocaine and reduction of extracellular concentration of Na+ from 154 mM to 100 mM, in all-or-none fashion, suggesting that spontaneous current spikes reflected spontaneous action potentials. From these results, it became evident that DRG neurons of adult rats had a nature to respond to NGF and obtained the abnormal hyperexcitability to fire spontaneously.  相似文献   
49.
50.
The chemokine receptors CCR5 and CXCR4 are an obvious target for HIV therapies. Two compounds, T-22 and AMD-3100, have been shown to inhibit infection of CXCR4-using HIV-1 isolates. The specificity of T-22 and AMD-3100 was further confirmed by their ability to block entry of HIV-1 in GHOST-CXCR4 transfected cells with no effect on viral entry in the GHOST-CCR5 cells. The ability of T-22 to block replication of diverse HIV-1 isolates (group M, subtypes A, B, D, E, and F as well as group O) and HIV-2 primary isolates with varying coreceptor specificities ranging from exclusive CCR5 usage to multiple coreceptor usage was examined in detail. T-22 was found to be highly effective (>90%) at blocking infection of diverse HIV-1 (subtypes A-F, and group O) and HIV-2 isolates that use multiple coreceptors in human PBMCs homozygous for a 32-bp deletion in CCR5 (CCR5-/-), but less effective in CCR5 +/+ PBMCs. Additionally, sequential primary HIV-1 isolates obtained from a longitudinal cohort who had switched from single coreceptor usage to a broad range of multiple receptors could be blocked effectively by both T-22 and AMD-3100 in CCR5-/- PBMCs. Our data suggest that CXCR4 antagonistic compounds are highly effective in blocking the entry of X4-tropic HIV-1, and that these compounds could be a useful additive to current anti-retroviral therapy for clinical management of HIV disease.  相似文献   
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