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121.
Although long known and the most prevalent movement disorder, pathophysiology of essential tremor (ET) remains controversial. The most accepted hypothesis is that it is caused by a dysfunction of the olivocerebellar system. Vilela Filho et al. [2001; Stereotact Funct Neurosurg 77:149–150], however, reported a patient with unilateral hand ET that was completely relieved after a stroke restricted to the contralateral posterior putamen and suggested that ET could be the clinical manifestation of posterior putamen hyperactivity. The present study was designed to evaluate this hypothesis in the most often used model of ET, harmaline‐induced tremor in rats. Fifty‐four male Wistar rats were randomly distributed into three groups: experimental (EG), surgical control (SCG), and pharmacological control (PCG) groups. EG animals underwent stereotactic unilateral posterior striatotomy. SCG rats underwent sham lesion at the same target. PCG served exclusively as controls for harmaline effects. All animals received, postoperatively, intraperitoneal harmaline, and the induced tremor was video‐recorded for later evaluation by a blind observer. Thirteen animals were excluded from the study. Limb tremor was reduced ipsilaterally to the operation in 20 of 21 rats of EG and in two of nine of SCG, being asymmetric in one of 10 of PCG rats. Comparisons between EG × SCG and EG × PCG were statistically significant, but not between SCG × PCG. Limb tremor reduction was greater in anterior than in posterior paws. Lateral lesions yielded better results than medial lesions. These results suggest that the posterior striatum is involved with harmaline‐induced tremor in rats and support the hypothesis presented. © 2013 Wiley Periodicals, Inc.  相似文献   
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Activation of protein kinase C? (PKC?) confers protection against neuronal ischemia/reperfusion. Activation of PKC? leads to its translocation to multiple intracellular sites, so a mitochondria‐selective PKC? activator was used to test the importance of mitochondrial activation to the neuroprotective effect of PKC?. PKC? can regulate key cytoprotective mitochondrial functions, including electron transport chain activity, reactive oxygen species (ROS) generation, mitochondrial permeability transition, and detoxification of reactive aldehydes. We tested the ability of mitochondria‐selective activation of PKC? to protect primary brain cell cultures or mice subjected to ischemic stroke. Pretreatment with either general PKC? activator peptide, TAT‐Ψ?RACK, or mitochondrial‐selective PKC? activator, TAT‐Ψ?HSP90, reduced cell death induced by simulated ischemia/reperfusion in neurons, astrocytes, and mixed neuronal cultures. The protective effects of both TAT‐Ψ?RACK and TAT‐Ψ?HSP90 were blocked by the PKC? antagonist ?V1–2, indicating that protection requires PKC? interaction with its anchoring protein, TAT‐?RACK. Further supporting a mitochondrial mechanism for PKC?, neuroprotection by TAT‐Ψ?HSP90 was associated with a marked delay in mitochondrial membrane depolarization and significantly attenuated ROS generation during ischemia. Importantly, TAT‐Ψ?HSP90 reduced infarct size and reduced neurological deficit in C57/BL6 mice subjected to middle cerebral artery occlusion and 24 hr of reperfusion. Thus selective activation of mitochondrial PKC? preserves mitochondrial function in vitro and improves outcome in vivo, suggesting potential therapeutic value clinically when brain ischemia is anticipated, including neurosurgery and cardiac surgery. © 2013 Wiley Periodicals, Inc.  相似文献   
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Background

Exercise improves quality of life (QoL). However, little is known concerning the effects of different volumes of strength exercise on QoL. The aims of this study are to: (1) evaluate the effects of water-based strength exercise on QoL of healthy young women and (2) compare the effects of different volumes of water-based strength exercises on QoL of healthy young women.

Methods

Sixty-six participants were randomly allocated into four groups with different volumes of exercise. The participants performed water-based strength exercises for 20 weeks, two times a week, supervised by trained physiologists.

Results

A significant improvement was found in overall QoL (F = 5.96; p = 0.018) and in physical (F = 22.01; p < 0.001), psychological (F = 8.408; p = 0.006) and environment domains (F = 8.34; p = 0.006). In addition, a significant decrease of depressive symptoms was found (F = 22.32; p < 0.001). No difference was found between groups in any domain of QoL or depressive symptoms.

Conclusion

Water-based strength exercise improves specific domains of QoL and decreases depressive symptoms of young healthy women. Different volumes of exercise promote similar effects on QoL and depressive symptoms.
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The key lesions in antibody‐mediated kidney transplant rejection (ABMR) are microcirculation inflammation (peritubular capillaritis and/or glomerulitis lesions, abbreviated “pg”) and glomerular double contours (cg lesions). We used these features to explore subphenotypes in 164 indication biopsies with ABMR‐related diagnoses: 137 ABMR (109 pure and 28 mixed with T cell–mediated rejection [TCMR]) and 27 transplant glomerulopathy (TG), identified from prospective multicenter studies. The lesions indicated three ABMR subphenotypes: pgABMR, cgABMR, and pgcgABMR. Principal component analysis confirmed these subphenotypes and showed that TG can be reclassified as pgcgABMR (n = 17) or cgABMR (n = 10). ABMR‐related biopsies included 45 pgABMR, 90 pgcgABMR, and 25 cgABMR, with four unclassifiable. Dominating all time intervals was the subphenotype pgcgABMR. The pgABMR subphenotype presented earliest (median <2 years), frequently mixed with TCMR, and was most associated with nonadherence. The cgABMR subphenotype presented late (median 9 years). Subphenotypes differed in their molecular changes, with pgABMR having the most histologic–molecular discrepancies (i.e. potential errors). Donor‐specific antibody (DSA) was not identified in 29% of pgcgABMR and 46% of cgABMR, but failure rates and molecular findings were similar to cases where DSA was known to be positive. Thus, ABMR presents distinct subphenotypes, early pg‐dominant, late cg‐dominant, and combined pgcg phenotype, differing in time, molecular features, accompanying TCMR, HLA antibody, and probability of nonadherence.  相似文献   
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This study tested the adequacy of feeding as an unconditioned stimulus (US) to condition an endocrine response (plasma cortisol increase) in the cichlid fish Nile tilapia (Oreochromis niloticus). In a first study, conditioning was confirmed in grouped fish in the only experiment using single-held Nile tilapia. In this test a conditioned stimulus (CS - aeration off) was associated with a stressor (air emersion for 2 min- US). We then assessed whether several events of paired CS-US resulted in a conditioned endocrine response (CR), in this case an increase in plasma cortisol after presentation of the CS only. Before testing feeding as US, the postprandial or social holding condition for feeding effects on cortisol levels was tested. Nile tilapia showed increased cortisol after feeding associated to social context (grouped fish), but not to food only (single-held fish). In a third study, feeding was tested as US in an experiment similar to the first study but an increase in feeding-induced cortisol could not be conditioned. The absence of CR suggests that the stressor affects acquisition of this response, which may be a consequence of stimulus intensity or biological relevance. This study expands the recently reported Pavlovian conditioning paradigm for endocrine response in fish.  相似文献   
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Introduction: Bruxism is among the most chronic dental problems worldwide, and its perception may increase indicatively the condition of people’s health, avoiding future health problems. Technologic solutions have improved considerably owing to new diagnostic and treatment technologies and their automation. This review aims to assess therapeutic methods for bruxism through analysis of patent applications spanning recent decades.

Areas covered: Patent families of bruxism, and products available on the market. Data were obtained through Questel Orbit from the European Patent Office on a worldwide basis using Cooperative Patent Classification (CPC), analyzing 134 patent families. The products on the market were mapped and classified as used for diagnosis, treatment, or both.

Expert opinion: This technological prospect has shown that the technological field of bruxism is growing toward smaller, automated devices; there is still no predominant owner of the technologies. Products are expected to provide home use with a high degree of reliability and specificity, using the Internet of Things (telemedicine associated with industry 4.0) and enabling real-time diagnosis.  相似文献   

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