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81.
Mark William Lopes Flávia Mahatma Schneider Soares Nelson de Mello Jean Costa Nunes Aurilene Gomes Cajado Daniel de Brito Fabiano Mendes de Cordova Rodrigo Maranguape Silva da Cunha Roger Walz Rodrigo Bainy Leal 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2013,226(2):153-163
The pilocarpine model in rodents reproduces the main features of mesial temporal lobe epilepsy related to hippocampus sclerosis (MTLE-HS) in humans. It has been demonstrated in this model that the phosphorylation of the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor GluR1 subunit is increased 1 h after pilocarpine treatment. Moreover, alterations in the levels of glutamate transporters have been associated with chronic epilepsy in humans. Despite these studies, the profile of these changes has not yet been addressed. We analyzed the protein content and phosphorylation profile of the AMPA receptor GluR1 subunit by western blotting. We also used quantitative real-time polymerase chain reaction to analyze the expression of glial glutamate transporters and the N-methyl-d-aspartate receptor NR1 subunit in the hippocampus (Hip) and cerebral cortex (Ctx) at different time points after pilocarpine-induced status epilepticus (Pilo-SE) in male adult Wistar rats. Biochemical analysis was performed in the Hip and Ctx at 1, 3, 12 h (acute period), 5 days (latent period), and 50 days (chronic period) after Pilo-SE. Key findings include an increase in the phosphorylation of GluR1-Ser845 in the Ctx and GluR1-Ser831 in the Hip at different times during the acute period, and a decrease in the total content of the GluR1 subunit in the Ctx in the latent period. There was a down-regulation of the mRNA expression and protein levels of EAAT1 and EAAT2, and a decrease of the NR1 mRNA expression, in the Ctx during the latent period. Notably, during the chronic period, the EAAT2 mRNA expression and protein levels decreased while the NR1 mRNA levels increased in the Hip. Taken together, our findings suggest a time- and structure-dependent imbalance of glutamatergic transmission in response to Pilo-SE, which might be associated with either epileptogenesis or the seizure threshold in MTLE-HS. 相似文献
82.
Silvia A.S. Vedovello Ana Letícia Mello de Carvalho Larissa C. de Azevedo Patrícia R. dos Santos Mario Vedovello-Filho Marcelo de C. Meneghim 《The Angle orthodontist》2020,90(4):564
ObjectivesTo evaluate the impact of anterior occlusal conditions in the mixed dentition on item-level analysis of oral health–related quality of life (OHRQoL).Materials and MethodsA population-based cross-sectional study of 787 children aged 8 to 10 years was conducted. The Child Perceptions Questionnaire (CPQ8-10) was used to evaluate OHRQoL, and the analysis of item levels was performed on CPQ8-10 domains. Anterior occlusal characteristics were diagnosed according to the Dental Aesthetic Index criteria. Individual analyses were performed relating the outcome as independent variables. The variables with P < .20 in the individual analyses were tested in multiple logistic regression models, and those with P < .10 remained in the model. The adjusted odds ratio (OR) was estimated with a 95% confidence interval (CI).ResultsNo associations were found with regard to anterior occlusal characteristics (P < .001) after the variables of the previous determinants were adjusted for multivariate analysis. However, the following variables were significantly associated with negative impact on OHRQoL item levels: sex, in oral symptoms (OR = 1.42; CI, 1.07–1.89) and emotional well-being (OR = 1.34; CI, 1.00–1.79); race, in oral symptoms (OR = 1.48; CI, 1.10–1.98), emotional well-being (OR = 1.54; CI, 1.14–2.06), and social well-being (OR = 1.34; CI, 1.00–1.80); and family income in functional limitation (OR = 1.46; CI, 1.06–2.02), emotional well-being (OR = 1.71; CI, 1.21–2.42), and social well-being (OR = 1.59; CI, 1.14–2.21).ConclusionsAnterior occlusal conditions did not affect the levels of OHRQoL items. 相似文献
83.
Cristiane Delgado Alves Rodrigues Marcos Mello Moreira Núbia Maria Freire Vieira Lima Luciana Castilho de Figueirêdo Ant?nio Luis Eiras Falc?o Orlando Petrucci Junior Desanka Dragosavac 《Brazilian Journal Of Cardiovascular Surgery》2015,30(1):24-32
Objective
A retrospective cohort study was preformed aiming to verify the presence of transient dysfunction of gas exchange in the postoperative period of cardiac surgery and determine if this disorder is linked to cardiorespiratory events.Methods
We included 942 consecutive patients undergoing cardiac surgery and cardiac procedures who were referred to the Intensive Care Unit between June 2007 and November 2011.Results
Fifteen patients had acute respiratory distress syndrome (2%), 199 (27.75%) had mild transient dysfunction of gas exchange, 402 (56.1%) had moderate transient dysfunction of gas exchange, and 39 (5.4%) had severe transient dysfunction of gas exchange. Hypertension and cardiogenic shock were associated with the emergence of moderate transient dysfunction of gas exchange postoperatively (P=0.02 and P=0.019, respectively) and were risk factors for this dysfunction (P=0.0023 and P=0.0017, respectively). Diabetes mellitus was also a risk factor for transient dysfunction of gas exchange (P=0.03). Pneumonia was present in 8.9% of cases and correlated with the presence of moderate transient dysfunction of gas exchange (P=0.001). Severe transient dysfunction of gas exchange was associated with patients who had renal replacement therapy (P=0.0005), hemotherapy (P=0.0001), enteral nutrition (P=0.0012), or cardiac arrhythmia (P=0.0451).Conclusion
Preoperative hypertension and cardiogenic shock were associated with the occurrence of postoperative transient dysfunction of gas exchange. The preoperative risk factors included hypertension, cardiogenic shock, and diabetes. Postoperatively, pneumonia, ventilator-associated pneumonia, renal replacement therapy, hemotherapy, and cardiac arrhythmia were associated with the appearance of some degree of transient dysfunction of gas exchange, which was a risk factor for reintubation, pneumonia, ventilator-associated pneumonia, and renal replacement therapy in the postoperative period of cardiac surgery and cardiac procedures. 相似文献84.
After laryngectomy for treatment of laryngeal cancer, the distal esophageal contractions have low amplitude. Our hypothesis is that proximal esophageal contractions are also impaired. We studied the proximal esophageal contractions in 20 laryngectomized patients (16 men) with a mean age of 44.2 years, 12 rehabilitated patients with esophageal speech, and 12 controls (7 men, mean age of 46.5 years). We used the manometric method with continuous perfusion. All subjects were studied in the sitting position and performed five swallows of a 5-ml bolus of water alternated with five dry swallows. The contractions were measured 2 cm below the high-pressure zone of the pharyngoesophageal transition. The results showed that the amplitude and duration of contractions were different in laryngectomized patients compared with controls. The amplitude of contractions of patients (wet swallows: 37.3 ± 20.7 mmHg, mean ± SD) was lower than that of controls (81.1 ± 31.7 mmHg). The duration of contractions was also lower in laryngectomized patients (2.2 ± 0.7 s) than in controls (2.6 ± 0.6 s). We conclude that the proximal esophageal contraction amplitude and duration of laryngectomized patients are lower than controls, a fact suggesting that laryngectomy may affect the proximal esophageal contractions. 相似文献
85.
86.
87.
Valéria de Mello Márcia Cristina de Azevedo Prata Márcio Roberto da Silva Erik Daemon Luciane Santos da Silva Flávia del Gaudio Guimarães Alessandra Ésther de Mendonça Evelize Folly Fernanda Maria Pinto Vilela Lilian Henriques do Amaral Lucio Mendes Cabral Maria da Penha Henriques do Amaral 《Parasitology research》2014,113(12):4431-4437
The cattle tick, Rhipicephalus (Boophilus) microplus, has caused serious harm to livestock raising in Brazil, considering the costs of controlling it, loss of revenue due to smaller production of milk and meat, and damage to leather, in addition to transmitting diseases. The use of medicinal plants is considered an alternative to the recurring resistance to chemicals. Due to the need for efficient alternatives with less environmental impact, this study aimed to develop contact formulations with essential oils from the Java citronella (Cymbopogon winterianus) and clove (Syzygium aromaticum) plants and to assess in vitro the effects in different stages of the tick cycle. In the present study, concentrations from 0.5–15.0 % of the essential oils incorporated in the formulations were used. The ticks from different geographical areas were treated with those formulations, and their effects on the production levels of eggs, on the larvae hatching, and their efficiency on ticks were assessed. The obtained results were compared with other commercial acaricidal products. After the 20th day of treatment, the formulations with citronella essential oil had 2.09–55.51 % efficiency, depending on the concentration of the oil incorporated. The efficiency of the treatment with formulations containing clove essential oil was higher, from 92.47–100 %. The results showed the acaricidal effects of the formulations tested when compared to commercial chemical products. In vivo studies should be performed in order to assess the efficiency of those formulations in the fields, aiming to use these products as an alternative for controlling cattle ticks. 相似文献
88.
D. A. C. Botte I. L. Noronha D. M. A. C. Malheiros T. V. Peixoto S. B. V. de Mello 《Clinical and experimental immunology》2014,177(2):381-390
Alpha‐melanocyte stimulating hormone (α‐MSH) is a neuropeptide exhibiting anti‐inflammatory activity in experimental models of autoimmune diseases. However, no studies thus far have examined the effects of α‐MSH on systemic lupus erythematosus (SLE). This study aimed to determine the effects of an α‐MSH agonist in induced murine lupus. Here we employed female Balb/cAn mice in which lupus was induced by pristane. Groups of lupus animals were treated daily with the α‐MSH analogue [Nle4, DPhe7]‐α‐MSH (NDP–MSH) (1·25 mg/kg) injected intraperitoneally or saline for 180 days. Normal animals comprised the control group. Arthritis incidence, plasma immunoglobulin (Ig)G isotypes, anti‐nuclear antibodies (ANA) and plasma cytokines were evaluated. Renal function was assessed by proteinuria and histopathological lesion. Glomerular levels of IgG, α‐smooth muscle actin (α‐SMA), inducible nitric oxide synthase (iNOS), C3, CD3, melanocortin receptors (MCR)1, corticotrophin‐releasing factor (CRF) and α‐MSH was estimated by immunohistochemistry. When compared with normal controls, lupus animals exhibited increased arthritis, IgG levels, ANA, interleukin (IL)‐6, IL‐10, proteinuria and mesangial cell proliferation together with glomerular expression of α‐SMA and iNOS. Glomerular expression of MCR1 was reduced in lupus animals. NDP‐MSH treatment reduced arthritis scores by 70% and also diminished IgG1 and IgG2a levels and ANA incidence. In the glomerulus, NDP–MSH treatment reduced cellularity by 50% together with reducing IgG deposits, and expression levels of α‐SMA, iNOS and CRF were also all decreased. Taken together, our results suggest for the first time that α‐MSH treatment improves several parameters of SLE disease activity in mice, and indicate that this hormone is an interesting potential future treatment option. 相似文献
90.
Concolino P Mello E Patrosso MC Penco S Zuppi C Capoluongo E 《Metabolism: clinical and experimental》2012,61(4):519-524
More than 90% of all cases of congenital adrenal hyperplasia (CAH) result from steroid 21-hydroxylase gene (CYP21A2) mutations. The CYP21A2 gene is located in the human leukocyte antigen (HLA) class III region on the short arm of chromosome 6p21.3, along with an inactive pseudogene, CYP21A1P, that is 98% homologous in its coding sequence with CYP21A2. Most CYP21A2 mutations result from intergenic recombinations between CYP21A2 and the closely linked CYP21A1P pseudogene. Rare mutations not generated by gene conversion account for only 5% to 10% of 21-hydroxylase deficiency alleles. However, detection of these rare and spontaneous mutations has continued to expand worldwide. We identified 2 novel CYP21A2 missense mutations (p.H282N and p.Y191H) in 2 Italian patients with simple-virilizing and nonclassic CAH forms. Functional analysis of these CYP21A2 mutations was performed. Functional in vitro assay for mutagenized CYP21A2 enzymes was performed in transiently transfected mammalian cells to test the residual enzyme activity and the apparent kinetic values. The residual activities obtained allowed us to classify the p.H282N and p.Y191H variants as simple-virilizing and nonclassic CAH associated mutations, respectively. These results correlate with the rate of severity of the patients' disease. This finding provides a further contribution for assisting in the diagnosis of CAH patients. 相似文献