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951.
Pinheiro AP Galdo-Álvarez S Rauber A Sampaio A Niznikiewicz M Gonçalves OF 《Research in developmental disabilities》2011,32(1):133-147
Williams syndrome (WS), a neurodevelopmental genetic disorder due to a microdeletion in chromosome 7, is described as displaying an intriguing socio-cognitive phenotype. Deficits in prosody production and comprehension have been consistently reported in behavioral studies. It remains, however, to be clarified the neurobiological processes underlying prosody processing in WS.This study aimed at characterizing the electrophysiological response to neutral, happy, and angry prosody in WS, and examining if this response was dependent on the semantic content of the utterance. A group of 12 participants (5 female and 7 male), diagnosed with WS, with age range between 9 and 31 years, was compared with a group of typically developing participants, individually matched for chronological age, gender and laterality. After inspection of EEG artifacts, data from 9 participants with WS and 10 controls were included in ERP analyses.Participants were presented with neutral, positive and negative sentences, in two conditions: (1) with intelligible semantic and syntactic information; (2) with unintelligible semantic and syntactic information (‘pure prosody’ condition). They were asked to decide which emotion was underlying the auditory sentence.Atypical event-related potentials (ERP) components were related with prosodic processing (N100, P200, N300) in WS. In particular, reduced N100 was observed for prosody sentences with semantic content; more positive P200 for sentences with semantic content, in particular for happy and angry intonations; and reduced N300 for both types of sentence conditions.These findings suggest abnormalities in early auditory processing, indicating a bottom-up contribution to the impairment in emotional prosody processing and comprehension. Also, at least for N100 and P200, they suggest the top-down contributions of semantic processes in the sensory processing of speech. This study showed, for the first time, that abnormalities in ERP measures of early auditory processing in WS are also present during the processing of emotional vocal information. This may represent a physiological signature of underlying impaired on-line language and socio-emotional processing. 相似文献
952.
Bastos Gonçalves F Metz R Hendriks JM Rouwet EV Muhs BE Poldermans D Verhagen HJ 《The Journal of cardiovascular surgery》2010,51(5):657-667
Aortic dissection is a devastating cardiovascular condition with an incidence of 3,5:100 000. It is classified according to anatomic extent, mechanism of lesion, duration from index event and course (uncomplicated vs. complicated). Intramural hematoma and penetrating aortic ulcers share many of the features of classic dissections, but tend to occur in older patients with advanced atherosclerosis. In uncomplicated type-B dissection, conservative treatment with tight blood pressure and heart rate control is safe and effective. Early stent-graft implantation may, however, result in more favorable aortic remodeling and reduced late complications. For acute complicated cases intervention is usually required. Stent-graft coverage of the entry tear frequently resolves malperfusion, but the role of the false lumen in organ perfusion must be assessed and endovascular revascularization performed if necessary. In chronic type-B dissections, coverage of the entry tear likely results in continued pressurization of the false lumen due to rigidity of the dissecting membrane and distal fenestrations. Better understanding of the different disease mechanisms involved, imaging advances and introduction of dedicated stent-grafts are expected to further improve patient outcomes in the future. Primary and secondary pharmacological prevention, stricter follow-up protocols and screening of family members may also prove valuable. Better patient selection will allow preventive treatment with low morbidity for those at higher risk of complications. 相似文献
953.
954.
Background/Aims
In a previous issue published in Gut and Liver, we found that erosive changes in the esophagogastroduodenal mucosa were strongly correlated with increased levels of volatile sulfur-containing compounds (VSC), suggesting that halitosis could be a symptom reflecting the erosive status of the upper gut mucosa. Together with other studies showing a possible association between halitosis and gastroesophageal reflux disease (GERD), under the premise that halitosis could be one of extraesophageal manifestations of erosive GERD (ERD), we investigated the significance of Halimeter ppb levels on ERD compared to non-erosive gastroesophageal reflux disease (NERD).Methods
Subjects were assigned to the NERD group if there was no evidence of esophageal erosive changes on endoscopy, despite reflux symptoms, and to the ERD group if they had GERD A, B, C, or D (according to the Los Angeles classification). The VSC levels were measured in all patients with either a Halimeter (before endoscopy) or by gas chromatography of the gastric juices aspirated during endoscopy.Results
The VSC level differed significantly between the NERD and ERD groups (p<0.0001), suggesting that this can be used to discriminate between NERD and ERD. However, the VSC level did not differ significantly with the severity of GERD. Even though hiatal hernia and a body mass index of >24 kg/m2 was significantly associated with ERD, there was no correlation with Halimeter ppb levels. Minimal-change lesions exhibited the highest VSC levels, signifying that minimal change lesions can be classified as ERD based on our finding that halimeter ppb levels were descrimitive of erosive change.Conclusions
Erosive changes in the esophageal mucosa were strongly associated with VSC levels, supporting the hypothesis that halitosis can be a potential biomarker for the discrimination between ERD and NERD, reflecting the presence of erosive change in the lower esophagogastric junction. 相似文献955.
The authors describe ten cases of syringomyelia without hindbrain herniation depicted by preoperative magnetic resonance imaging (MRI) in supine position. However, the herniation was observed in all cases during the operation with the patient in sitting position. The postoperative MRI revealed an intense reduction of the syrinx in all patients, as well as it was also observed a clinical amelioration in all cases. The surgical treatment was based on a large craniectomy with the patient in sitting position, tonsillectomy, large opening of the fourth ventricle and duraplasty with creation of a large cisterna magna. 相似文献
956.
957.
Natacha Gonçalves‐Sousa Julie C. Ribot Ana deBarros Daniel V. Correia Íris Caramalho Bruno Silva‐Santos 《European journal of immunology》2010,40(1):61-70
γδ T cells are highly cytolytic lymphocytes that produce large amounts of pro‐inflammatory cytokines during immune responses to multiple pathogens. Furthermore, their ability to kill tumor cells has fueled the development of γδ‐T‐cell‐based cancer therapies. Thus, the regulation of γδ‐T‐cell activity is of great biological and clinical relevance. Here, we show that murine CD4+CD25+ αβ T cells, the vast majority of which express the Treg marker, Foxp3, abolish key effector functions of γδ T cells, namely the production of the pro‐inflammatory cytokines, IFN‐γ and IL‐17, cytotoxicity, and lymphocyte proliferation in vitro and in vivo. We further show that suppression is dependent on cellular contact between Treg and γδ T cells, results in the induction of an anergic state in γδ lymphocytes, and can be partially reversed by manipulating glucocorticoid‐induced TNF receptor‐related protein (GITR) signals. Our data collectively dissect a novel mechanism by which the expansion and pro‐inflammatory functions of γδ T cells are regulated. 相似文献
958.
We recently found that the antinociceptive effects produced by intrathecal administration of sildenafil, a phosphodiesterase 5 inhibitor, were reversed by a nonspecific adenosine receptor antagonist, suggesting that adenosine receptors are involved in sildenafil-induced antinociception. Four adenosine receptor subtypes have been identified: A1, A2A, A2B, and A3. We examined the involvement of spinal adenosine receptor subtypes in the antinociceptive effects of intrathecal sildenafil. Intrathecal catheters were implanted in male SD rats, and nociception was assessed using the formalin test, which consisted of a subcutaneous injection of 50 μl of 5% formalin solution into the hind paw. We examined the effects of an adenosine A1 receptor antagonist (CPT), an adenosine A2A receptor antagonist (CSC), an adenosine A2B receptor antagonist (alloxazine), and an adenosine A3 receptor antagonist (MRS 1220) on sildenafil-induced antinociception. Intrathecal sildenafil suppressed formalin-induced flinching during phases 1 and 2 of the test in a dose-dependent manner. Intrathecal CPT, CSC, alloxazine, and MRS 1220 all suppressed the antinociceptive effects of sildenafil during both phases of the formalin test. These results suggest that sildenafil is an effective treatment for acute pain and the facilitated pain state at the spinal level. Additionally, spinal adenosine A1, A2A, A2B, and A3 receptors may play a role in sildenafil-induced antinociception. 相似文献
959.
Torres BB Caldeira FM Gomes MG Serakides R de Marco Viott A Bertagnolli AC Fukushima FB de Oliveira KM Gomes MV de Melo EG 《International journal of experimental pathology》2010,91(6):530-536
Dantrolene has been shown to be neuroprotective by reducing neuronal apoptosis after brain injury in several animal models of neurological disorders. In this study, we investigated the effects of dantrolene on experimental spinal cord injury (SCI). Forty-six male Wistar rats were laminectomized at T13 and divided in six groups: GI (n = 7) underwent SCI with placebo and was euthanized after 32 h; GII (n = 7) underwent laminectomy alone with placebo and was euthanized after 32 h; GIII (n = 8) underwent SCI with dantrolene and was euthanized after 32 h; GIV (n = 8) underwent SCI with placebo and was euthanized after 8 days; GV (n = 8) underwent laminectomy alone with placebo and was euthanized after 8 days; and GVI (n = 8) underwent SCI with dantrolene and was euthanized after 8 days. A compressive trauma was performed to induce SCI. After euthanasia, the spinal cord was evaluated using light microscopy, TUNEL staining and immunochemistry with anti-Caspase-3 and anti-NeuN. Animals treated with dantrolene showed a smaller number of TUNEL-positive and caspase-3-positive cells and a larger number of NeuN-positive neurons, both at 32 h and 8 days (P ≤ 0.05). These results showed that dantrolene protects spinal cord tissue after traumatic SCI by decreasing apoptotic cell death. 相似文献
960.
Glauco A Westphal Anderson Roman Gon?alves Ant?nio Bedin Raquel Bissacotti Steglich Eliezer Silva Luiz Francisco Poli-de-Figueiredo 《Clinics (S?o Paulo, Brazil)》2010,65(2):189-194