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Physical or emotional stress can affect the female reproductive physiology and angiotensin II (Ang II) is a hormone that participates in the stress response and also in the control of reproductive hormones. The present study aimed at evaluating the effects of acute stress in the morning and afternoon of proestrus on sexual behavior and ovulation and the participation of Ang II in the stress-induced effects. Female rats with regular estrous cycles were used. Several different stress protocols were tested in the morning and in the afternoon of proestrus: restraint stress 10 min; restraint stress 1 h and ether stress, respectively. The participation of Ang II was evaluated by injecting Ang II receptor antagonists (losartan and PD123319) 15 min before stress. The lordosis quotient was recorded and the number of oocytes was counted. Plasma levels of luteinizing hormone, progesterone, prolactin and corticosterone were measured. All types of stress in the morning of proestrus induced a reduction in the number of oocytes. Restraint stress (1 h) in the afternoon of proestrus induced a significant reduction in the lordosis quotient. Peripheral and central losartan, but not PD123319, injections partly reverted the effects of stress on ovulation in the morning of proestrus. Acute stress in the morning of proestrus also reduced luteinizing hormone, progesterone and prolactin surges later on the same day. In conclusion, acute stress on the day of proestrus can affect female reproductive physiology. Moreover, the angiotensinergic system, through AT(1) receptors, participates in the effects of acute stress in the morning of proestrus.  相似文献   
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Euchroma Dejean, 1833 (Buprestidae: Coleoptera) is a monotypic genus comprising the species Euchroma gigantea, with populations presenting a degree of karyotypic variation/polymorphism rarely found within a single taxonomic (specific) unit, as well as drastically incompatible meiotic configurations in populations from extremes of the species range. To better understand the complex karyotypic evolution of E. gigantea, the karyotypes of specimens from five populations in Brazil were investigated using molecular cytogenetics and phylogenetic approaches. Herein, we used FISH with histone genes as well as sequencing of the COI to determine differential distribution of markers and relationships among populations. The analyses revealed new karyotypes, with variability for chromosome number and morphology of multiple sex chromosome mechanisms, occurrence of B chromosome variants (punctiform and large ones), and high dispersion of histone genes in different karyotypes. These data indicate that chromosomal polymorphism in E. gigantea is greater than previously reported, and that the species can be a valuable model for cytogenetic studies. The COI phylogenetic and haplotype analyses highlighted the formation of three groups with chromosomally polymorphic individuals. Finally, we compared the different karyotypes and proposed a model for the chromosomal evolution of this species. The species E. gigantea includes at least three cytogenetically polymorphic lineages. Moreover, in each of these lineages, different chromosomal rearrangements have been fixed. Dispersion of repetitive sequences may have favored the high frequency of these rearrangements, which could be related to both adaptation of the species to different habitats and the speciation process.  相似文献   
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There is a considerable gap between the offer and the demand for mental health treatment of children and adolescents, especially in low- and middle-income countries (LMICs). Permanent education in these countries is a promising and needed strategy to reduce this gap. This study was designed to evaluate the perceived impact of an educational intervention for child and adolescent mental health professionals in Brazil, the Child and Adolescent Mental Health Specialization Course (CESMIA). The intervention consisted of a 360-hour interprofessional postgraduation course. The CESMIA offered lectures and small-group case discussions for exchanging their experiences in dealing with the patients. The students were placed in these groups according to their professions in order to ensure a proportional distribution of healthcare professionals in each group. The evaluation employed a quasi-experimental design by the use of a knowledge, attitude, and practice (KAP) survey. The 39 participants reported significant improvement in all KAP dimensions. More specifically, the data indicated a 17% improvement for attitudes, a 9.4% increase for knowledge, and a 14% improvement for the practice dimensions. The CESMIA appeared to improve the level of knowledge of participants and their attitudes and actions towards patients, which reinforces the relevance of similar courses.  相似文献   
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Ageing is associated with changes in body composition that may result in sarcopenic obesity (SO). Interleukin-6 (IL-6) and C-reactive protein (CRP) are important inflammatory markers related to ageing. SO has been examined as an important public health problem, but its association with inflammatory markers has yet to be investigated. The aim of this study was to investigate the association between SO-related phenotypes and inflammatory markers in postmenopausal women. A total of 130 women (66·7 ± 5·2 years) underwent body composition evaluation using dual-energy X-ray absorptiometry. Volunteers were classified according to a SO definition previously described in the literature. Waist circumference (WC) and handgrip strength (HG) were also measured. Blood samples were collected for CRP, tumour necrosis factor and IL-6 measurements. All the inflammatory markers were higher in SO individuals when compared to non-SO; however, only IL-6 reached statistical significance (median 3·34 versus 1·37 pg ml−1; P<0·05). Also, CRP was significantly correlated (P<0·01) with body mass index (rs = 0·34), fat mass (FM; rs = 0·25) and WC (rs = 0·33). Similarly, IL-6 levels were significantly correlated (P<0·05) to age (rs = 0·19), FM (rs = 0·19) and WC (rs = 0·17). HG was found to be significantly reduced among subjects with higher IL-6 levels (= 0·02). In summary, the combination of reduced muscle mass and excess body fat (i.e. SO) is associated with elevated inflammatory markers in postmenopausal women. Moreover, CRP and IL-6 are associated with SO-related phenotypes in this population.  相似文献   
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This study evaluated, for the first time, the genetic diversity of Toxoplasma gondii isolates from free-range chickens from the state of Paraíba, Northeast Brazil. Tissue samples from 33 chickens from properties in five municipalities of Paraíba (Esperança, Olho d’Água, Malta, Monteiro, and Patos) were bioassayed in mice. The brains of mice infected with T. gondii cysts were used for DNA extraction and genotyping. Genotyping was performed using 11 PCR-RFLP markers and 15 microsatellite (MS) markers. Complete genotyping results were obtained for 29 isolates, with nine genotypes detected by RFLP and 15 genotypes identified by MS. Three genotypes (#273, #274, and #277) have only been recently identified from pigs in the region. Brazilian clonal types BrII and BrIII were identified from one isolate each. Clonal types I, II, and III were not detected by RFLP. Genotype #13 (Caribbean 1), detected in 48.3% (14/29) of isolates from four of the five municipalities investigated, was the most prevalent genotype in the state of Paraíba. However, the MS analysis showed that of these 14 isolates, only four were unique genotypes, and considering the distance between the municipalities from where they were collected, it is possible that only seven are independent isolates while the others are clones. The other genotypes were restricted to different microregions. The results indicate that the Caribbean 1 lineage of T. gondii is circulating widely in Northeast Brazil. The genotypic diversity of T. gondii in the state of Paraíba is high, and microsatellite analysis revealed this diversity with higher resolution than PCR-RFLP.

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