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1.
Talita da Silva Mendes de Farias Ariclécio Cunha de Oliveira Sandra Andreotti Fernanda Gaspar do Amaral Patrícia Chimin André Ricardo Alves de Proença Francisco Leonardo Torres Leal Rogério Antonio Laurato Sertié Amanda Baron Campana Andressa Bolsoni Lopes Arnaldo Henrique de Souza José Cipolla‐Neto Fabio Bessa Lima 《Journal of pineal research》2015,58(3):251-261
Melatonin, the main hormone produced by the pineal gland, is secreted in a circadian manner (24‐hr period), and its oscillation influences several circadian biological rhythms, such as the regulation of clock genes expression (chronobiotic effect) and the modulation of several endocrine functions in peripheral tissues. Assuming that the circadian synchronization of clock genes can play a role in the regulation of energy metabolism and it is influenced by melatonin, our study was designed to assess possible alterations as a consequence of melatonin absence on the circadian expression of clock genes in the epididymal adipose tissue of male Wistar rats and the possible metabolic repercussions to this tissue. Our data show that pinealectomy indeed has impacts on molecular events: it abolishes the daily pattern of the expression of Clock, Per2, and Cry1 clock genes and Pparγ expression, significantly increases the amplitude of daily expression of Rev‐erbα, and affects the pattern of and impairs adipokine production, leading to a decrease in leptin levels. However, regarding some metabolic aspects of adipocyte functions, such as its ability to synthesize triacylglycerols from glucose along 24 hr, was not compromised by pinealectomy, although the daily profile of the lipogenic enzymes expression (ATP‐citrate lyase, malic enzyme, fatty acid synthase, and glucose‐6‐phosphate dehydrogenase) was abolished in pinealectomized animals. 相似文献
2.
Rubens Souza de OLIVEIRA Lanna Jamile Corrêa da COSTA Fernanda Atanaena Gon?alves de ANDRADE Wilson UIEDA Luzia Fátima Alves MARTORELLI Ana Paula de Arruda Geraldes KATAOKA Elizabeth Salbé Travassos da ROSA Pedro Fernando da Costa VASCONCELOS Armando de Souza PEREIRA Ant?nio Ismael Barros do CARMO Marcus Emanuel Barroncas FERNANDES 《Revista do Instituto de Medicina Tropical de S?o Paulo》2015,57(6):497-503
The outbreaks of rabies in humans transmitted by Desmodus rotundus in 2004 and 2005,
in the northeast of the Brazilian State of Para, eastern Amazon basin, made this a
priority area for studies on this zoonosis. Given this, the present study provides
data on this phenomenon in an urban context, in order to assess the possible
circulation of the classic rabies virus (RABV) among bat species in Capanema, a town
in the Amazon basin. Bats were collected, in 2011, with mist nets during the wet and
dry seasons. Samples of brain tissue and blood were collected for virological and
serological survey, respectively. None of the 153 brain tissue samples analyzed
tested positive for RABV infection, but 50.34% (95% CI: 45.67-55.01%) of the serum
samples analyzed were seropositive. Artibeus planirostris was the most common
species, with a high percentage of seropositive individuals (52.46%, 95% CI: 52.31
52.60%). Statistically, equal proportions of seropositive results were obtained in
the rainy and dry seasons (c2 = 0.057, d.f. = 1, p = 0.88). Significantly
higher proportions of males (55.96%, 95% CI: 48.96-62.96%) and adults (52.37%, 95%
CI: 47.35-57.39%) were seropositive. While none of the brain tissue samples tested
positive for infection, the high proportion of seropositive specimens indicates that
RABV may be widespread in this urban area. 相似文献
3.
4.
J J de Souza T Perlmann A A Herman O J Ransome R W Kantor 《Suid-Afrikaanse tydskrif vir geneeskunde》1987,71(11):690-692
The value of maternal C-reactive protein (CRP) levels as predictors of fetal and maternal infective morbidity and fetal mortality was assessed prospectively over a 6-month period in all cases of premature rupture of the fetal membranes or suspected premature labour. Statistical analysis of results showed that CRP at a level of 1.32 mg/dl is a sensitive marker of infective morbidity in mother and neonate. Furthermore, there was a significant association between raised CRP levels and low-birth-weight babies, suggesting that intra-uterine infection is a major cause of prematurity in the study population. 相似文献
5.
C Jardim C E Rochitte M Humbert G Rubenfeld D Jasinowodolinski C R R Carvalho R Souza 《The European respiratory journal》2007,29(3):476-481
Pulmonary arterial hypertension (PAH) is a disease of the small vessels in which there is a substantial increase in pulmonary vascular resistance leading to right ventricle failure and death. Invasive haemodynamic evaluation is mandatory not only for diagnosis confirmation but also to address prognosis and eligibility for the use of calcium-channel blockers through an acute vasodilator challenge. Noninvasive surrogate response markers to the acute vasodilator test have been sought. In the present study, the relationship between pulmonary artery distensibility, assessed using magnetic resonance imaging (MRI), and response to acute vasodilator tests was investigated. In total, 19 patients diagnosed with idiopathic PAH without any specific treatment were evaluated. Within a 48-h window after pulmonary artery catheterisation, patients underwent cardiac MRI. Cardiac index, calculated after the determination (invasively and noninvasively) of cardiac output, showed excellent correlation, as did right atrial pressure and right ventricle ejection fraction. Pulmonary artery distensibility was significantly higher in responders. A receiver operating characteristic curve analysis has shown that 10% distensibility was able to differentiate responders from nonresponders with 100% sensitivity and 56% specificity. The present findings suggest that magnetic resonance imaging and pulmonary artery distensibility may be useful noninvasive tools for the evaluation of patients with pulmonary hypertension. 相似文献
6.
Unusual central chorioretinitis as the first manifestation of early secondary syphilis 总被引:1,自引:0,他引:1
E C de Souza A E Jalkh C L Trempe S Cunha C L Schepens 《American journal of ophthalmology》1988,105(3):271-276
Three young, otherwise healthy patients had a similar picture of unilateral central chorioretinitis associated with severe visual loss. Fluorescein angiography disclosed diffuse leakage under the neurosensory retina in the posterior pole, associated with multifocal areas of staining along the retinal vessels. Systemic examination showed a positive fluorescent treponemal antibody absorption test and a sharp increase in VDRL titers, indicative of active secondary syphilis. The patients responded dramatically to penicillin treatment, with visual recovery and resolution of the fundus lesions. 相似文献
7.
8.
9.
Raph Hamers Sander Bontemps Marjan van den Akker Ruy Souza Júlio Penaforte Niels Chavannes 《Primary care respiratory journal》2006,15(5):299-306
AIMS: The developing world is particularly at risk of an increasing health burden due to an increased prevalence of Chronic Obstructive Pulmonary Disease (COPD) secondary to increasing tobacco consumption. However, research is scarce. The objectives of this study were to assess the current competence for diagnosing COPD in primary care in a resource-limited setting in Brazil, and to develop a local patient profile for case-finding. METHODS: 34 general practitioners (GPs) in five areas of northern Brazil recruited adult patients with principal complaints of cough and/or shortness of breath who then had spirometry (n = 142). RESULTS: For the dichotomous variable 'COPD' the degree of agreement between GP diagnosis (n = 64, 18.3%) and spirometric outcome (n = 36, 25.4%) was poor, with Kappa = 0.055 (SE 0.087) and DOR = 1.35. False-positive and false-negative diagnosis proportions were 19.8% and 75%, respectively. Independent risk factors were 'smoking history of more than five pack years' and 'presence of both dyspnoea and cough'. It requires the testing of 2.2 smokers with more than five pack years to detect one patient at risk. CONCLUSIONS: COPD is a common yet underdiagnosed disease in Brazilian primary care. Spirometry improves diagnostic competence and case-finding substantially. If applied in a pre-selected high-risk population, we believe spirometry can be a cost-effective diagnostic tool for case-finding in the resource-limited setting. This study provides important baseline information for effective guideline implementation. 相似文献
10.
Effects of age and age-related hearing loss on the neural representation of speech cues. 总被引:6,自引:0,他引:6
OBJECTIVE: To examine the effects of aging and age-related hearing loss on the perception and neural representation of a time-varying speech cue. METHODS: P1, N1 and P2 cortical responses were recorded from younger and older normal-hearing adults, as well as older adults with age-related hearing loss. Synthetic speech tokens representing 10 ms increments along a /ba/-/pa/ voice-onset-time (VOT) continuum were used to evoke the responses. Each participant's ability to discriminate the speech tokens was also assessed. RESULTS: Compared with younger participants, older adults with and without hearing loss had more difficulty discriminating 10 ms VOT contrasts. In addition, both older groups elicited abnormal neural response patterns. There were no significant age-related findings for P1 latency; however, N1 latencies were prolonged for both older groups in response to stimuli with increased VOT durations. Also, P2 latencies were delayed for both older groups. The presence of age-related hearing loss resulted in a significant increase in N1 amplitude in response to voiceless stimuli. CONCLUSIONS: Aging and age-related hearing loss alter temporal response properties in the central auditory system. Because both older groups had difficulty discriminating these same speech stimuli, we conclude that some of the perceptual difficulties described by older adults might be due to age-related changes regulating excitatory and inhibitory processes. SIGNIFICANCE: Some of the speech understanding difficulties expressed by elderly adults may be related to impaired temporal precision in the aging auditory system. This might explain why older adults frequently complain that wearing a hearing aid makes speech louder, but does not necessarily improve their ability to understand speech. 相似文献