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Purpose: Increasingly, evidence has shown that human papillomavirus (HPV) plays a role in the induction of certain carcinomas. The presence of HPV sequences in 56 previously untreated oral and pharyngolaryngeal carcinomas was examined by the polymerase chain reaction (PCR).Materials and Methods: After DNA extraction, samples underwent 40 replication cycles with specific oligonucleotide primers corresponding to sequences from the E6 open-reading frame of HPV-6b, HPV-16, and HPV-18. To determine the E6 genomic integration, positive samples were processed with specific primers for the corresponding HPV L1 genes. Genomic HPV DNA cloned into PBR 322 was used as positive control.Results: HPV E6 DNA of the 6b and 16 types was detected in 14 patients (25%). The L1 gene was not present.Conclusion: Detected HPV E6 DNA might be integrated into the cell genome in the positive cases as indicated by the absence of the L1 gene-coding for the viral capside. Histological and clinical parameters, such as tumor location, degree of differentiation, stage, recurrence, and survival rates, were unrelated to the presence of HPV.  相似文献   
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Aplidine is a promising antitumor agent derived from the Mediterranean tunicate Aplidium albicans. We have found that Aplidine at nM concentrations (10-100 nM) induced apoptosis in human leukemic cell lines and primary leukemic cell cultures from leukemic patients. Inhibition of the Fas (CD95)/Fas ligand (CD95L) signaling pathway with an antagonistic anti-Fas antibody partially inhibited Aplidine-induced apoptosis. L929 cells were resistant to Aplidine action but underwent apoptosis after transfection with human Fas cDNA. Aplidine induced a rapid and sustained c-Jun NH(2)-terminal kinase activation, and pretreatment with curcumin or SP600125 inhibited Aplidine-induced c-Jun NH(2)-terminal kinase activation and apoptosis. However, inhibition of extracellular signal-regulated kinase and p38 kinase signaling pathways did not affect Aplidine-induced apoptosis. Aplidine induced caspase-3 activation, and caspase inhibition prevented Aplidine-induced apoptosis. Aplidine failed to induce apoptosis in MCF-7 breast cancer cells, defective in caspase-3, additionally implicating caspase-3 in its proapoptotic action. Aplidine also triggered an early release of cytochrome c from mitochondria, and overexpression of bcl-2 by gene transfer abrogated mitochondrial cytochrome c release and apoptosis. Aplidine rapidly induced cleavage of Bid, a mediator that connects the Fas/CD95 cell death receptor to the mitochondrial apoptosis pathway. Primary cultures of normal human cells, including hepatocytes and resting peripheral blood lymphocytes, were spared or weakly affected after Aplidine treatment. Nevertheless, mitogen (phytohemagglutinin/interleukin-2)-activated T lymphocytes resulted sensitively to the apoptotic action of Aplidine. Thus, Aplidine is an extremely potent and rapid apoptotic inducer on leukemic cells that triggers Fas/CD95- and mitochondrial-mediated apoptotic signaling routes, and shows a rather selective apoptotic action on cancer cells and activated T cells.  相似文献   
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Sleep deprivation can exert antidepressant effects in humans in less than 24 h, making it the fastest acting antidepressant treatment. However, it is rarely used clinically because the effect disappears once the subject goes back to sleep. An understanding of the neurobiological mechanisms underlying the antidepressant effect of sleep deprivation should help to develop new rapidly acting antidepressant strategies. In the present report, an animal model of depression (the forced-swim test) was used to determine whether the effects of total sleep deprivation parallel those obtained with antidepressant drugs. Using the disk-over-water method, rats deprived of sleep for 24 h exhibited increased swimming behavior when compared to cage control rats, mimicking the effects of serotonergic antidepressants. After 48 h, sleep-deprived rats exhibited increased swimming when compared to both cage control and stimulus control rats, demonstrating that the effect is due to sleep deprivation per se, and not to extraneous factors inherent in the sleep deprivation protocol (such as stress and movement). We believe that this paradigm can be used to study the neurobiological mechanisms of rapid antidepressant effects induced by sleep deprivation.  相似文献   
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Chikungunya virus (CHIKV) vertical transmission occurs due to maternal viremia in the prepartum. Clinical presentation in neonates can be varied; however, the consequences of intrauterine exposure on the immune response are unclear. Thus, we aimed to analyze inflammatory alterations in children exposed to maternal CHIKV infection. This is a cross-sectional study that included children exposed to maternal CHIKV infection (confirmed by RT-qPCR and/or IgM). Circulant immune mediators were analyzed by a multiplex assay. RESULTS: We included 33 children, with a mean age of 3 ± 2.9 months-old, and 19 (57.6%) were male. Only one child presented neurological alterations. CHIKV-exposed infants showed elevated levels of MIP-1α, MIP-1β, and CCL-2 (p < 0.05). Pro-inflammatory cytokines such as TNFα, IL-6, and IL-7 (p < 0.0001) were also increased. In addition, lower levels of PDGF-BB and GM-CSF were observed in the same group (p < 0.0001). Principal component (PC) analysis highlighted a distinction in the inflammatory profile between groups, where PC explained 56.6% of the alterations. Our findings suggest that maternal exposure to CHIKV can affect the circulating levels of pro-inflammatory cytokines during the infants’ first year of life. The long-term clinical consequences of these findings should be investigated.  相似文献   
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ObjectiveThe aim of this study was to create and validate an abbreviated version of the Spanish Transsexual Voice Questionnaire for Male-to-Female Transsexuals (SvTVQMtF).SettingThe study was conducted by two referral hospitals for voice feminization surgery and by a university department of psychology and speech therapy, all in Spain.Subjects and methodsWe prospectively studied 51 male-to-female transsexuals who underwent voice feminization surgery between January 2017 and December 2018. The SvTVQMtF was completed before and after surgery, and the 10 items with the greatest variation were selected by clinical consensus of an expert panel to develop the short version of the SvTVQMtF (SvTVQMtF-10). The correlation between the total score and the score for each item on the SvTVQMtF and the SvTVQMtF-10 was studied. The internal consistency of the SvTVQMtF-10 was analysed.ResultsGood correlation (Pearson coefficient above .90) was found between the two questionnaires. A significant correlation was found between the total SvTVQMtF-10 score and the score for each item. A significant negative correlation was found between the SvTVQMtF and fundamental frequency after voice feminization surgery. Cronbach's α was .79.ConclusionThe SvTVQMtF-10 is a valid short version of the SvTVQMtF and can be used to quantify voice-related quality of life in MtF transsexuals.  相似文献   
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Bone tissue responds to gonadal steroid hormones and vitamin D. Bone turnover is the process of replacing deteriorated tissue, and estrogens play a significant role at the tissular, cellular and molecular levels. After menopause, bone resorption predominates and increases the risk of osteoporosis. The vitamin D endocrine system also regulates bone metabolism through specific receptors and non-genomic mechanisms. Vitamin D deficiency is widespread among the general population and has been related to low sun exposure and low dietary intake. Vitamin D supplementation is an important antiresorptive measure and helps to maintain musculoskeletal health.  相似文献   
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