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951.
Perinatal asphyxia remains as one of the most important causes of death and disability in children, without an effective treatment. Moreover, little is known about the long-lasting behavioral consequences of asphyxia at birth. Therefore, the main aim of the present study was to investigate the motor, emotional and cognitive functions of adult asphyctic rats. Experimental subjects consisted of rats born vaginally (CTL), by cesarean section (C+), or by cesarean section following 19 min of asphyxia (PA). At three months of age, animals were examined in a behavioral test battery including elevated plus maze, open field, Morris water maze, and an incentive downshift procedure. Results indicated that groups did not differ in anxiety-related behaviors, although a large variability was observed in the asphyctic group and therefore, the results are not completely conclusive. In addition, PA and C+ rats showed a deficit in exploration of new environments, but to a much lesser extent in the latter group. Spatial reference and working memory impairments were also found in PA rats. Finally, when animals were downshifted from a 32% to a 4% sucrose solution, an attenuated suppression of consummatory behavior was observed in PA rats. These results confirmed and extended those reported previously about the behavioral alterations associated with acute asphyxia around birth.  相似文献   
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Neurologists should anticipate and recognize the onset of respiratory failure in patients with neuromuscular diseases. Symptoms vary according to the speed of onset of respiratory muscle weakness. Catastrophic situations usually occur in three clinical scenarios: 1) incorrect management of acute respiratory failure of neuromuscular origin, autonomic dysfunction or during general anaesthesia of patients with neuromuscular diseases ; 2) incorrect prognosis and treatment due to the lack of a correct diagnosis. This situation is more common in ventilated patients with associated muscular weakness, acute neuropathies or motor neuron disease, and 3) inappropriate medical intervention in patients with neuromuscular disease with a definitive diagnosis but longstanding disease (amyotrophic lateral sclerosis, spinal muscular atrophy, myotonic dystrophy and other muscular dystrophies).  相似文献   
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We have investigated the effect of stem cell delivery on the release of hypoxia-inducible factor 1 alpha (HIF-1α) in peripheral circulation and myocardium in experimental myocardial ischemia. Closed-chest, reperfused myocardial infarction (MI) was created in domestic pigs. Porcine mesenchymal stem cells (MSCs) were cultured and delivered (9.8?±?1.2?×?106) either percutaneously NOGA-guided transendocardially (Group IM) or intracoronary (Group IC) 22?±?4 days post-MI. Pigs without MSC delivery served as sham control (Group S). Plasma HIF-1α was measured at baseline, immediately post- and at follow-up (FUP; 2 h or 24 h) post-MSC delivery by ELISA kit. Myocardial HIF-1α expression of infarcted, normal myocardium, or border zone was determined by Western blot. Plasma level of HIF-1α increased immediately post-MI (from 278?±?127 to 631?±?375 pg/ml, p?<?0.05). Cardiac delivery of MSCs elevated the plasma levels of HIF-1α significantly (p?<?0.05) in groups IC and IM immediately post-MSC delivery, and returned to baseline level at FUP, without difference between the groups IC and IM. The myocardial tissue HIF-1α expression in the infarcted area was higher in Group IM than in Group IC or S (1,963?±?586 vs. 1,307?±?392 vs. 271?±?110 activity per square millimeter, respectively, p?<?0.05), while the border zone contained similarly lower level of HIF-1α, but still significantly higher as compared with Group S. Trend towards increase in myocardial expression of HIF-1α was measured in Group IM at 24 h, in contrast to Group IC. In conclusion, both stem cell delivery modes increase the systemic and myocardial level of HIF-1α. Intramyocardial delivery of MSC seems to trigger the release of angiogenic HIF-1α more effectively than does intracoronary delivery.  相似文献   
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Tumour necrosis factor-alpha antagonist drugs represent a significant advance in the treatment of inflammatory diseases, such as rheumatoid arthritis, spondyloarthropathies, and intestinal inflammatory disease. The increase in tuberculosis with infliximab is known, but there is less data available that specifically associates tuberculosis with adalimumab. We present the cases of 2 patients with rheumatoid arthritis and one patient with ankylopoietic spondylitis on treatment with adalimumab, who developed pulmonary and disseminated tuberculosis, despite following the screening and prophylaxis measures recommended in guidelines. We also review the association between treatment with tumour necrosis factor-alpha antagonists and tuberculosis.  相似文献   
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Chronic hepatitis B is a major health problem, with more than 350 million people infected worldwide. Available therapies have limited efficacy and require long-term continuous and expensive treatments, which often lead to the selection of resistant viral variants and rarely eliminate the virus. Immunotherapies have been investigated as a promising new approach. Several vaccine formulations have been clinically tested in chronic patients, none of which have clearly demonstrated efficacy so far. In this study we evaluated a new vaccination strategy comprising the simultaneous co-administration by the nasal and parenteral routes of a multicomponent vaccine formulation in BALB/C and HBsAg-transgenic mice. The formulation under study contains the surface and nucleocapsid antigens of the HBV, and was co-administered by the nasal route and three parenteral routes. For parenteral administration we also evaluated the immunogenicity of the antigenic mixture with alum or without the adjuvant. The immune response was evaluated by ELISA and IFN-γ ELISPOT assays. Our results indicate that all variants generated a strong antibody response in the sera against both antigens, but differed in their capacity to induce cellular immune responses against the surface antigen. Mice immunized by the nasal and subcutaneous routes without alum generated the highest IFN-γ-secreting CD8+ T-cell response, and results in this transgenic mouse model showed that there is no need to include alum. In conclusion, our results indicate that the immunization routes have to be carefully selected before carrying out clinical trials to optimize the immune response and promote further clinical development.  相似文献   
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Novel Sr-substituted calcium phosphate cement (CPC) loaded with doxycycline hyclate (DOXY-h) was employed to elucidate the effect of strontium substitution on antibiotic delivery. The cement was prepared using as reactants Sr-substituted β-tricalcium phosphate (Sr-β-TCP) and acidic monocalcium phosphate monohydrate. Two different methods were used to load DOXY-h: (i) the adsorption on CPC by incubating the set cement in drug-containing solutions; and (ii) the use of antibiotic solution as the cement liquid phase. The results revealed that the Sr-substituted cement efficiently adsorbs the antibiotic, which is attributed to an enhanced accessibility to the drug-binding sites within this CPC. DOXY-h desorption is influenced by the initial adsorbed amount and the cement matrix type. Furthermore, the fraction of drug released from CPCs set with DOXY-h solution was higher, and the release rate was faster for the CPC prepared with 26.7% Sr-β-TCP. The analysis of releasing profiles points to Fickian diffusion as the mechanism responsible for antibiotic delivery. We can conclude that Sr substitution in secondary calcium phosphate cements improves their efficiency for DOXY-h adsorption and release. The antibiotic loading method provides a way to switch from rapid and complete to slower and prolonged drug release.  相似文献   
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