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31.
The structure and function of the central nervous system strongly depend on the organization and efficacy of the incoming sensory input. A disruption of somesthetic input severely alters the metabolic activity, electrophysiological properties and even gross anatomical features of the primary somatosensory cortex. Here we examined, in the rat somatosensory cortex, the neuroprotective and therapeutic effects of artificial sensory stimulation after irreversible unilateral transection of a peripheral sensory nerve (the infraorbital branch of the trigeminal nerve). The proximal stump of the nerve was inserted into a silicon tube with stimulating electrodes, through which continuous electrical stimulation was applied for 12 h/day (square pulses of 100 μs, 3.0 V, at 20 Hz) for 4 weeks. Deafferented animals showed significant decreases in cortical evoked potentials, cytochrome oxidase staining intensity (layers II–IV), cortical volume (layer IV) and number of parvalbumin‐expressing (layers II–IV) and calbindin‐D28k‐expressing (layers II/III) interneurons. These deafferentation‐dependent effects were largely absent in the nerve‐stimulated animals. Together, these results provide evidence that chronic electrical stimulation has a neuroprotective and preservative effect on the sensory cortex, and raise the possibility that, by controlling the physical parameters of an artificial sensory input to a sectioned peripheral nerve, chronically deafferented brain regions could be maintained at near‐‘normal’ conditions. Our findings could be important for the design of sensory neuroprostheses and for therapeutic purposes in brain lesions or neural degenerative processes.  相似文献   
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Astrocytes are important sources of proinflammatory mediators such as iNOS and TNFalpha in the diseased central nervous system. In previous studies, we showed that the cytokine IL-1 plays a critical role in the activation of human astrocytes to express TNFalpha and the inducible form of nitric oxide synthase (iNOS). In the present study, we have addressed the role of the MAP-kinase pathway in the signaling events leading to the induction of these genes. Treatment with SB203580, a specific inhibitor of p38 mitogen-activated protein kinases (MAPK), potently inhibited IL-1-mediated induction of iNOS and TNFalpha in cultures of human fetal astrocytes. In contrast, PD98059, an upstream inhibitor of the extracellular regulated kinase (ERK)1/2 pathway, had little or no effect. Interestingly, SB203580 reduced the mRNA expression for iNOS, TNFalpha, and IL-6, indicating inhibition prior to translation. Transfection of astrocytes with a dominant-negative Jun-NH(2)-terminal kinase (JNK) construct also reduced iNOS expression. Western blot analysis showed phosphorylated p38 and JNK in IL-1-activated astrocytes, and phosphorylated ERK in both resting and activated cells. Electrophoretic mobility shift assay (EMSA) showed that IL-1 induced NF-kappaB and AP-1 DNA complex formation in astrocytes, and that SB203580 inhibited AP-1 complex formation. Taken together, these results demonstrate the differential roles played by the three MAP kinases in human astrocyte inflammatory gene activation and point to a crucial function of p38 and JNK MAP kinases in IL-1-mediated astrocyte activation.  相似文献   
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The General and Sport Nutrition Knowledge Questionnaire (GeSNK) is an instrument that has been developed and validated to assess the level of nutrition knowledge in adolescents and young adults. The aim of the present study was to validate the GeSNK questionnaire in a group of Spanish adolescents in the framework of a Nutrition Education Programme in Secondary Schools in Andalusia, Spain. This cross-sectional questionnaire validation study was developed in two phases: translation-cultural adaptation and validation. A total of 305 adolescents aged 11 to 17 years, studying from the first to the third year of compulsory secondary education, participated on a voluntary basis. The GeSNK questionnaire consists of 62 items: 29 items for the General Nutrition section and 33 items for the Sports Nutrition section. Cronbach’s alpha coefficient for the complete questionnaire (GeSNK Total) was: 0.934; for the GeSNK General Nutrition section it was 0.918; and for the GeSNK Sports Nutrition section it was 0.856. The stability measured by the correlation coefficient for the General Nutrition section was 0.406 (p = 0.000); for the Sports Nutrition section it was 0.198 (p = 0.017); and for GeSNK Total the stability was 0.545 (p = 0.000). The questionnaire also demonstrated adequate construct validity. We therefore conclude that the Spanish version of the GeSNK questionnaire is a valid instrument to measure the level of knowledge in general nutrition and sports nutrition in adolescents.  相似文献   
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Ultrasonography as part of the pre-natal diagnosis in high risk pregnancies may detect a number of fetal malformations that need to be re-evaluated for continuation or termination of pregnancy. Two fetuses, in two different patients with diabetes mellitus, were found to have significant intrauterine malformations detected by ultrasonography at 18 and 20 weeks gestational age, respectively. Post-mortem examination on both fetuses demonstrated the findings known as the caudal regression syndrome. The clinico-pathological features and obstetrical management of diabetic mothers whose pregnancies are complicated with this rare malformation are discussed.  相似文献   
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Seventy-four families of probands with oculoauriculovertebral anomaly were evaluated, including 116 parents and 195 off-spring. Relatives were examined to identify ear malformations, mandibular anomalies, and other craniofacial abnormalities. For segregation analysis using POINTER, selection of the sample was consistent with single as-certainment. Different population liabilities were used for probands and relatives, because affection was narrowly defined for probands and broadly defined for relatives. The hypothesis of no genetic transmission was rejected. The evidence favored autosomal dominant inheritance; recessive and polygenic models were not distinguishable. © 1992 Wiley-Liss, Inc.  相似文献   
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Objective

To determine the possible causes of recurrent miscarriage in our environment and the pregnancy rate in these couples.

Material and methods

An observational retrospective study was carried out in 172 women who attended our unit for two or more recurrent miscarriages between 2002 and 2008.

Results

A total of 80.2% of the women became pregnant. Of these, 81.2% carried the fetus to term. The results of clinical study were normal in 70.9%. The alterations found were uterine in 48%, genetic in 2% and coagulation alterations in 44%. These alterations were associated in 6% of the patients.

Conclusions

Most of the couples consulting for recurrent miscarriage will not receive an etiologic diagnosis after clinical study. Reproductive prognosis worsens as the number of miscarriages increases. However, up to 80.2% of these women become pregnant again, of whom 81.1% will deliver a healthy neonate.  相似文献   
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