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151.
A single dose of S‐ketamine induces long‐term antidepressant effects and decreases oxidative stress in adulthood rats following maternal deprivation 下载免费PDF全文
Gislaine Z. Réus Anelise S. Carlessi Stephanie E. Titus Helena M. Abelaira Zuleide M. Ignácio Jaine R. da Luz Beatriz I. Matias Livia Bruchchen Drielly Florentino Andriele Vieira Fabricia Petronilho João Quevedo 《Developmental neurobiology》2015,75(11):1268-1281
Ketamine, an antagonist of N‐methyl‐d ‐aspartate receptors, has produced rapid antidepressant effects in patients with depression, as well as in animal models. However, the extent and duration of the antidepressant effect over longer periods of time has not been considered. This study evaluated the effects of single dose of ketamine on behavior and oxidative stress, which is related to depression, in the brains of adult rats subjected to maternal deprivation. Deprived and nondeprived Wistar rats were divided into four groups nondeprived + saline; nondeprived + S‐ketamine (15 mg/kg); deprived + saline; deprived + S‐ketamine (15 mg/kg). A single dose of ketamine or saline was administrated during the adult phase, and 14 days later depressive‐like behavior was assessed. In addition, lipid damage, protein damage, and antioxidant enzyme activities were evaluated in the rat brain. Maternal deprivation induces a depressive‐like behavior, as verified by an increase in immobility and anhedonic behavior. However, a single dose of ketamine was able to reverse these alterations, showing long‐term antidepressant effects. The brains of maternally deprived rats had an increase in protein oxidative damage and lipid peroxidation, but administration of a single dose of ketamine reversed this damage. The activities of antioxidant enzymes superoxide dismutase and catalase were reduced in the deprived rat brains. However, ketamine was also able to reverse these changes. In conclusion, these findings indicate that a single dose of ketamine is able to induce long‐term antidepressant effects and protect against neural damage caused by oxidative stress in adulthood rats following maternal deprivation. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 75: 1268–1281, 2015 相似文献
152.
G Correia de Faria Santarém R de Cleva Marco Aurélio Santo Aline Biaseto Bernhard Alexandre Vieira Gadducci Julia Maria D’Andrea Greve Paulo Roberto Santos Silva 《PloS one》2015,10(6)
Background
Obesity is associated with mobility reduction due to mechanical factors and excessive body fat. The six-minute walk test (6MWT) has been used to assess functional capacity in severe obesity.Objective
To determine the association of BMI, total and segmental body composition with distance walked (6MWD) during the six-minute walk test (6MWT) according to gender and obesity grade.Setting
University of São Paulo Medical School, Brazil; Public Practice.Methods
Functional capacity was assessed by 6MWD and body composition (%) by bioelectrical impedance analysis in 90 patients.Results
The mean 6MWD was 514.9 ± 50.3 m for both genders. The male group (M: 545.2 ± 46.9 m) showed a 6MWD higher (p = 0.002) than the female group (F: 505.6 ± 47.9 m). The morbid obese group (MO: 524.7 ± 44.0 m) also showed a 6MWD higher (p = 0.014) than the super obese group (SO: 494.2 ± 57.0 m). There was a positive relationship between 6MWD and fat free mass (FFM), FFM of upper limps (FFM_UL), trunk (FFM_TR) and lower limbs (FFM_LL). Female group presented a positive relationship between 6MWD and FFM, FFM_UL and FFM_LL and male group presented a positive relationship between 6MWD and FFM_TR. In morbid obese group there was a positive relationship between 6MWD with FFM, FFM_UL, FFM_TR and FFM_LL. The super obese group presented a positive relationship between 6MWD with FFM, FFM_TR and FFM_LL.Conclusions
Total and segmental FFM is associated with a better walking capacity than BMI. 相似文献153.
Nícholas F. de Camargo Juliana F. Ribeiro Amabílio J. A. de Camargo Emerson M. Vieira 《Acta theriologica》2014,59(1):183-191
Investigation of the effect of endogenous and exogenous factors on the diet of animals is necessary for a better understanding of their feeding habits. This approach can provide relevant information on the autoecology of a species and its ecological interactions. We investigated the composition and intraspecific variation in the diet of the marsupial Gracilinanus agilis in areas of dry woodland forests (i.e., cerradão) in the Cerrado of Central Brazil, taking into consideration the availability of prey (arthropods) in the environment. We found insects, spiders, birds, and fruits in the scats of G. agilis. Insects (orders Hymenoptera, Isoptera, Hemiptera, and Coleoptera) and fruits were the most frequently consumed resources. Males fed more heavily on insects than females did, whereas during the warm–wet season (October to April), the reproductive females fed on insects more than the nonreproductive females did. On the other hand, the consumption of fruits and vertebrates did not vary between seasons, sexes, or according to female reproductive condition. Moreover, reproductive females fed more frequently on ants and beetles than nonreproductive females did. We also detected both positive (for Isoptera and Hemiptera) and negative (for Hymenoptera) selection of insects during the cool–dry season, whereas in the warm–wet season, these resources were consumed according to their availability in the environment. Our study revealed that G. agilis is an insectivore–omnivore species, but fruits also are a relevant part of its diet. This marsupial seemed to select their prey qualitatively according to its energy demands and nutritional requirements. 相似文献
154.
Ivandilson Pessoa Pinto de Menezes Fernanda Amato Gaiotto Lucia Vieira Hoffmann Ana Yamaguishi Ciampi Paulo Augusto Vianna Barroso 《Genetica》2014,142(1):99-108
Gossypium mustelinum is a wild cotton relative found only in the semiarid region of Bahia state in Brazil, and changes caused by humans in the natural habitat of this species have endangered the existence of several natural populations. Information about the occurrence and genetic composition of these populations is necessary to design effective conservation measures. The aim of this study was to characterize the in situ maintenance mode and assess the genetic diversity of G. mustelinum populations in the basin of the De Contas River. A sample of 205 G. mustelinum specimens was collected from the margins of the Jacaré, Riacho Quixaba, Riacho Serra Azul, and Riacho Riachão rivers and genotyped using 13 SSR primer pairs. In general, all G. mustelinum populations exhibit inadequate in situ maintenance, predominantly due to the deforestation of riparian vegetation and herbivory. The observed total genetic diversity of G. mustelinum was significant (H E = 0.489), highly structured (F ST = 0.534), and organized in homozygous genotypes (F IS = 0.873). The high observed inbreeding level is consistent with the predominance of self-fertilization and geitonogamy (t m = 0.234). In addition, the pattern of genetic structure tended to form groups that coincided with the collection sites, i.e., first clustering within subpopulations, then within populations, and finally within the closest populations. Thus, the observed genetic diversity is likely to be rapidly lost, and conservation measures should therefore be undertaken. 相似文献
155.
156.
Vieira Mde L Singh RP Derendorf H 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(29):2967-2973
A specific and reliable HPLC-PDA method for the quantitative determination of triamcinolone acetonide, budesonide and fluticasone propionate (as internal standards) in small volumes of microdialysate and rat plasma was developed. An efficient solid-phase extraction (SPE) procedure for plasma samples yielded extremely clean extracts with overall recovery of 104.3% and 95.7% for triamcinolone acetonide (TA) and fluticasone propionate, respectively. Plasma extracts obtained after SPE and microdialysis samples were directly injected on a C18 column to separation. The method has been validated with good linearity, sensitivity, specificity and high accuracy (RE -5.28% to 9.14%) and precision (CV 0.50% to 6.62%) on both matrices. In stability studies, TA and budesonide were stable during storage and assay procedures. The method was applied to a pharmacokinetic study in rodents using microdialysis to determine protein unbound TA concentrations in blood and muscle. 相似文献
157.
Valente F Lago BV Castro CA Almeida AJ Gomes SA Soares CC 《Memórias do Instituto Oswaldo Cruz》2010,105(8):970-977
An estimated 360 million people are infected with hepatitis B virus (HBV) worldwide. Among these, 65 million live in Africa. Despite the high levels of hepatitis B in Africa, HBV epidemiology is still poorly documented in most African countries. In this work, the epidemiological and molecular characteristics of HBV infection were evaluated among the staff, visitors and adult patients (n = 508) of a public hospital in Luanda, Angola. The overall prevalence of hepatitis B core antibody (anti-HBc) and hepatitis B surface antigen was 79.7% and 15.1%, respectively. HBV infection was higher in males and was more prevalent in individuals younger than 50 years old. HBV-DNA was detected in 100% of HBV "e" antigen-positive serum samples and in 49% of anti-hepatitis Be antibody-positive samples. Thirty-five out of the 40 HBV genotypes belonged to genotype E. Circulation of genotypes A (4 samples) and D (1 sample) was also observed. The present study demonstrates that HBV infection is endemic in Luanda, which has a predominance of genotype E. This genotype is only sporadically found outside of Africa and is thought to have emerged in Africa at a time when the trans-Atlantic slave trade had stopped. 相似文献
158.
159.
160.
Ana R Seabra Cristina P Vieira Julie V Cullimore Helena G Carvalho 《BMC plant biology》2010,10(1):183