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Chronic intermittent hypoxia (CIH), the main feature of obstructive sleep apnea, enhances carotid body (CB) chemosensory responses to acute hypoxia. In spite of that, the primary molecular target of CIH in the CB remains unknown. A key step of the hypoxic response in the CB is the chemoreceptor cell depolarization elicited by the inhibition of K+ channels. Thus, we tested the hypothesis that CIH potentiates the hypoxic-induced depolarization of rat CB chemoreceptor cells by enhancing the inhibition of a background K+ TASK-like channel. Membrane potential, single channel and macroscopic currents were recorded in the presence of TEA and 4-aminopyridine in CB chemoreceptor cells isolated from adult rats exposed to CIH. The CIH treatment did not modify the resting membrane properties but the hypoxic-evoked depolarization increased by 2-fold. In addition, the hypoxic inhibition of the TASK-like channel current was larger and faster in glomus cells from CIH-treated animals. This novel effect of CIH may contribute to explain the enhancing effect of CIH on CB oxygen chemoreception.  相似文献   
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A 47-year-old woman was diagnosed with dural carotid cavernous fistula (CCF) in her right eye (RE). Scans of the choroid using Spectralis optic coherence tomography (OCT) demonstrated significant asymmetry in subfoveal choroidal thickness (RE 451 μm, left eye (LE) 367 μm). This asymmetry disappeared after the fistula was embolizated through the ophthalmic artery (RE 341 μm; LE 340 μm). This case suggests that OCT should be considered as an ancillary test in the diagnosis of CCF.  相似文献   
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A 38-year-old male presented to the emergency room suffering acute pain in his left eye. Two months before he had been submitted to uneventful non-penetrating deep sclerectomy and one month before to YAG-laser goniopuncture. Examination showed iris herniation into the trabeculo-descemet’s window. Surgical reduction was carried out through a peripheral corneal incision, and a large air bubble was injected into the anterior chamber. Four days later a wide laser peripheral iridotomy was performed. This technique can transform a non-penetrating technique into a full-trabeculectomy, without reopening the superficial flap.  相似文献   
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In recent years, efforts to improve cancer therapy have focused on developing new anticancer agents, such as mitocans. These agents include vitamin E analogues and suppress cancer by inducing apoptosis by targeting mitochondria. Alpha tocopheryl succinate (α-TOS) is the most effective form of vitamin E analogues causing inhibition of proliferation and apoptosis of cancer cells. Both in vitro and in vivo studies have demonstrated that α-TOS selectively kills tumor cells with little or no effect on normal cells. Treatment with α-TOS shows great promise for future clinical applications, as it causes cell death, at least in part, by selectively inducing apoptosis by mitochondrial destabilization. This review presents an overview of perspectives on α-TOS and the potential uses of α-TOS in cancer treatment and other clinical applications.  相似文献   
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Lymphocytopenia and CD4+ T lymphocytopenia can be associated with many bacterial, fungal, parasite and viral infections. They can also be found in autoimmune and neoplastic diseases, common variable immunodeficiency syndrome, physical, psychological and traumatic stress, malnutrition and immunosuppressive therapy. Besides, they can also be brought into relation, without a known cause, with idiopathic CD4+ T lymphocytopenia. Among viral infections, the Retrovirus, specially the human immunodeficiency virus, is the most frequently cause. However, many acute viral infections, including cytomegalovirus and Epstein Barr virus can be associated with transient lymphocytopenia and CD4+ T lymphocytopenia. As is well known, transient lymphocytopenia and CD4+ T lymphocytopenia are temporary and overcome when the disease improves. Nonetheless, severe CD4+ T Lymphocytopenia associated with chronic infections by human herpes virus has not been reported. We describe 6 cases of human immunodeficiency virus negative patients, with chronic cytomegalovirus and Epstein Barr virus infections and profound lymphocytopenia with clinical symptoms of cellular immunodeficiency. These patients improved rapidly with ganciclovir or valganciclovir treatment. We claim here that it is important to consider the chronic human herpes virus infection in the differential diagnosis of profoundly CD4+ T lymphocytopenia etiology, when human immunodeficiency virus is absent, in order to start effective treatment and to determine, in future studies, the impact of chronic human herpes virus infection in human beings'' health.  相似文献   
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The objective of this study is to establish whether there is an association between the presence of FCGR3A V(176) polymorphism with SLE or its manifestations. We included 94 patients according to the 1982 ACR criteria as well as 98 controls matched by age and gender. The 11 ACR diagnostic criteria were analyzed on the clinical files. The polymorphism FCGR3A V(176) was determined by direct sequencing. There was not an association between the polymorphism FCGR3A V(176) with SLE or its main manifestations. The allelic frequency for F(176) was: 0.80 and 0.72 in cases and controls, respectively (P?=?0.09, IC95%: 0.42?C1.07); and the genotypic frequency in the group of cases was: 0.65 for homozygotes F(176)/F(176), 0.30 for heterozygotes and 0.05 for the homozygotes V(176)/V(176), while for the control group it was 0.53, 0.39 and 0.08, respectively. The polymorphism FCGR3A V(176) is not associated with SLE or any of its manifestations in patients with SLE from the West of Mexico.  相似文献   
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