INTRODUÇÃO: A isquemia cerebral é uma doença freqüente e de difícil tratamento médico. De particular interesse neurocirúrgico são as situações de vasoespasmo após hemorragia subaracnóidea, de oclusão ...temporária de vasos nas neurocirurgias e de tromboses de artérias intracranianas. A lesão cerebral resultante da isquemia depende da sua duração e pode ser agravada pela reperfusão do território isquêmico. Vários estudos clínicos e experimentais têm sido realizados para melhor entender esses fenômenos. OBJETIVO: Este trabalho visou a avaliação precoce dos efeitos da isquemia focal seguida da reperfusão no cérebro de gatos. MÉTODOS: A isquemia cerebral foi provocada por clipagem temporária da artéria cerebral média por tempos determinados com reperfusão durante 10 minutos, e avaliação foi efetuada através da análise da respiração mitocondrial no tecido isquemiado. Resultados - Houve redução significativa no consumo de O2 nas amostras de tecido cerebral isquemiado por 60 minutos, seguidos de 10 minutos de reperfusão, quando comparadas ao tecido cerebral contralateral (não isquemiado). CONCLUSÕES: Com base nos resultados obtidos, pode-se concluir que o tempo de duração da isquemia foi um fator determinante na alteração da respiração mitocondrial de gatos submetidos à isquemia e reperfusão de curta duração (alterações significativas apenas após 60 minutos de isquemia seguidos de 10 de reperfusão).
Peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha) is considered to play a pivotal role in the exercise-induced metabolic adaptation of skeletal muscle. Although the ...oxidized form of nicotinamide adenine dinucloetide (NAD(+))-dependent histone deacetylase SIRT1 has been shown to mediate PGC-1alpha-induced metabolic adaptation, the effect of endurance exercise on the SIRT1 protein remains to be elucidated. The purposes of this study were (1) to investigate the distribution of SIRT1 and PGC-1alpha proteins in skeletal muscle and (2) to examine the effects of acute endurance exercise and low- or high-intensity exercise training on SIRT1 and PGC-1alpha protein expressions and on the metabolic components in rat skeletal muscle. Both the SIRT1 and PGC-1alpha proteins preferentially accumulate in red oxidative muscles. Acute endurance exercise on a motor-driven treadmill (20 m/min, 18.5% incline, 45 minutes) increases the PGC-1alpha protein expression at 18 hours after exercise and the SIRT1 protein expression at 2 hours after exercise in the soleus muscle. In the training experiment, the rats were divided into control, low-intensity (20 m/min, 18.5% incline, 90 min/d), and high-intensity (30 m/min, 18.5% incline, 60 min/d) training groups. After 14 days of training, the SIRT1 and PGC-1alpha proteins, hexokinase activity, mitochondrial proteins and enzyme activities, and glucose transporter 4 protein in the soleus muscle were increased by both trainings. In the plantaris muscle, SIRT1, hexokinase activity, mitochondrial proteins and enzyme activities, and glucose transporter 4 were increased by high-intensity training whereas the PGC-1alpha was not. These results suggest that endurance exercise increases the skeletal muscle SIRT1 protein content. In addition, the findings also raise the possibility that the SIRT1 protein expression may play a potentially important role in such adaptations, whereas an increase in the PGC-1alpha protein expression is not necessary for such adaptations.
Abstract The vascular supercharge (additional microvascular anastomosis) has rarely been used for free flaps, and the blood circulation in the transferred tissue has not been recorded. We have made ...double vascular anastomoses during free jejunal transfer to reduce the possibility of loss of the flap from vascular occlusion. To evaluate the efficacy of additional arterial and venous anastomoses to improve the circulation in the transferred tissue, we analysed the results of blood gas measurements including venous partial pressure of oxygen ( p O2 ) and carbon dioxide ( p CO2 ) from the distal arcade vein. The free jejunal transfer was made using two pairs of arterial and venous anastomoses. Blood gas concentrations were analysed in samples drawn from the vein in the jejunal arcade before harvest, after the anastomosis of one paired artery and vein, after an additional arterial anastomosis, and after anastomoses of two pairs of artery/vein. The results showed that the venous p CO2 was not changed by increasing the number of anastomosed vessels. The venous p O2 was raised both by an additional arterial anastomosis and by two pairs of anastomoses, compared with that at the other two time points measured ( p = 0.04, p = 0.02, respectively). An additional arterial anastomosis seemed to have more effect on the p O2 than an additional artery/vein pair. Additional arterial and venous supercharging therefore has a similar effect on hyperbaric oxygenation. This effect is mainly caused by arterial supercharging.
Three gene polymorphisms of Nrf2, which regulate the expression of detoxifying and antioxidant genes, have been identified. We attempted to clarify the relationship of these polymorphisms with the ...carcinogenesis in the stomach.
The study was performed in 209 patients with gastric cancer and 198 patients with no evidence of gastric malignancies on upper gastroduodenal endoscopy. We employed PCR-SSCP method to detect gene polymorphisms.
Overall, both polymorphisms at position of -686/-684 and -650 were not significant risk factors of carcinogenesis in the stomach. However, the -686/-684 A/G allele carrier had a significantly reduced risk for gastric carcinogenesis (p = 0.022), especially of diffuse type (p = 0.020), in H. pylori-negative cases. The activity and inflammation scores in Nrf2 -686/-684 A/G carriers were significantly lower than those in the non-A/G carriers (p = 0.038 and p = 0.019, respectively).
The -686/-684 haplotype of Nrf2 gene may be associated with the development of gastric inflammation and with gastric carcinogenesis without the influence of H. pylori infection, although overall association with gastric carcinogenesis seems to be none.
Signaling by fibroblast growth factor (FGF) receptor (FGFR) 2IIIb regulates branching morphogenesis in the mammalian lung. FGFR2IIIb is primarily expressed in epithelial cells, whereas its ligands, ...FGF-10 and keratinocyte growth factor (KGF; FGF-7), are expressed in mesenchymal cells. FGF-10 null mice lack lungs, whereas KGF null animals have normal lung development, indicating that FGF-10 regulates lung branching morphogenesis. In this study, we determined the effects of FGF-10 on lung branching morphogenesis and accompanying gene expression in cultures of embryonic rat lungs.
Embryonic day 14 rat lungs were cultured with FGF-10 (0-250 ng/ml) in the absence or presence of heparin (30 ng/ml) for 4 days. Gene expression profiles were analyzed by Affymetrix microchip array including pathway analysis. Some of these genes, functionally important in FGF-10 signaling, were further analyzed by Northern blot, real-time PCR, in situ hybridization and immunohistochemistry.
Exogenous FGF-10 inhibited branching and induced cystic lung growth only in cultures containing heparin. In total, 252 upregulated genes and 164 downregulated genes were identified, and these included Spry1 (Sprouty-1), Spry2 (Sprouty-2), Spred-1, Bmp4 (bone morphogenetic protein-4, BMP-4), Shh (sonic hedgehog, SHH), Pthlh (parathyroid hormone-related protein, PTHrP), Dusp6 (MAP kinase phosphatase-3, MKP-3) and Clic4 (chloride intracellular channel-4, CLIC-4) among the upregulated genes and Igf1 (insulin-like growth factor-1, IGF-1), Tcf21 (POD), Gyg1 (glycogenin 1), Sparc (secreted protein acidic and rich in cysteine, SPARC), Pcolce (procollagen C-endopeptidase enhancer protein, Pro CEP) and Lox (lysyl oxidase) among the downregulated genes. Gsk3β and Wnt2, which are involved in canonical Wnt signaling, were up- and downregulated, respectively.
Unlike FGF-7, FGF-10 effects on lung branching morphogenesis are heparin-dependent. Sprouty-2, BMP-4, SHH, IGF-1, SPARC and POD are known to regulate branching morphogenesis; however, potential roles of CLIC-4 and MKP-3 in lung branching morphogenesis remain to be investigated. FGF-10 may also function in regulating branching morphogenesis or inducing cystic lung growth by inhibiting Wnt2/β-catenin signaling.
The contribution of cell wall components and nonstructural carbohydrate (NSC) to grain filling in rice (Oryza sativa L.) was clarified by investigating the differences in the dynamics of ...hemicellulose, sugar composition of hemicellulose, β-(1->3),(1->4)-glucan, and NSC among cultivars with different grain filling capacities. This investigation was performed using the stems of standard, high yield and low harvest index (HI) cultivars. Hemicellulose concentration in stems tended to decrease slightly during the grain filling stage. This decrease was attributed to a decrease in β-(1->3),(1->4)-glucan concentration, which was detected as a decrease in glucose composition of hemicellulose in the stems during the grain filling stage. The rate of decrease and decrease in the amount of β-(1->3),(1->4)-glucan in the stems differed among the cultivars. These were higher in high yield and high HI cultivars than in relatively low yield and low HI cultivars. Moreover, a positive correlation was observed between the rate of decrease in β-(1->3),(1->4)-glucan and NSC, indicating similarities in the dynamics of β-(1->3),(1->4)-glucan and NSC among the cultivars. When the top half of panicle was removed, β-(1->3),(1->4)-glucan and NSC concentrations in the culm and leaf sheath did not decrease during the grain filling stage. Therefore, the β-(1->3),(1->4)-glucan in stems might be one of the sources that supply substrate to panicle as well as NSC.
Noncoding microRNAs regulate the expression of various mRNAs. We attempted to clarify the relationship between miR-27a genome polymorphism and chronic gastritis. The study was performed in 179 ...patients with no evidence of gastric malignancy. The severity of histologic chronic gastritis was classified according to the updated Sydney system. The frequency of miR-27a G allele was 34.6%. Although the frequencies of miR-27a G allele were increased in subjects with peptic ulcer or severe mucosal atrophy, no significant differences were seen. The miR-27a polymorphism showed an interaction with gender in relation to gastric mucosal atrophy (P=.090). In only male subjects, the miR-27a polymorphism was associated with the gastric mucosal atrophy (P=.039) and both atrophy and metaplasia scores in G/G group were significantly higher than those in the other groups. The miR-27a genome region polymorphism may be an important definitive factor to develop the gastric mucosal atrophy in Japanese male subjects.
The dispersibility of mixed powder consisting of mullite and SiC whisker in solvents was assessed by carrying out sedimentation tests and viscosity measurements. The dispersibility was improved with ...increasing dispersant content and became good by adding dispersant over 0.5mass%. On the other hand, the dispersibility of mixed powder consisting of mullite and carbon-coated SiC whisker W(AC) was better than that of mixed powder consisting of mullite and W(A), despite the dispersibility of W(AC) being worse than that of W(A) if their particles existed alone in solvent. However, the dispersibility of the mixed powder consisting of mullite and W(AC) was lowered on addition of 0.5mass% dispersant and improved again on addition of 1.0mass%. The strength of SiC whisker-reinforced mullite composites became maximum by addition of 0.5-1.0mass% dispersant to the solvent used in powder-mixing.
A 69-year-old type 2 diabetic man was admitted due to diabetic gangrane. He had a history of subtotal gastrectomy. During hospitalization, he was treated with regular insulin and 300 mg/day of ...acarbose. He developed a low grade fever, cough and nasal discharge, and was given a compound "cold" remedy with anticholenergic properties. The next day, he suffered from a paralytic ileus. Oral intake and acarbose were withheld and the ileus spontaneously resolved after 2 days. These finding indicate the possibility that the ileus was triggered by drugs with anticholinergic properties in this elderly diabetic patient treated with α-glucosidase inhibitors.
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