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1.
A common factor V gene haplotype, the FVR2 haplotype (FVHR2), has been associated with a reduced cofactor activity in activated protein C-mediated activated factor VIII inactivation. Our aim was to investigate the role of FVHR2 as a possible determinant of factor VIII levels in a population study. A total of 516 individuals (401 men, 115 women; mean age 58.4 +/- 10.8 years) were enrolled within the frame of a regional cardiovascular survey, characterized for factor VIII coagulant activity (FVIII:c) and factor V coagulant activity (FV:c) levels, and genotyped for factor V polymorphisms. In men without signs of overt inflammation, FVHR2 carriers had higher levels of FVIII:c than noncarriers (154 IU/dl, 95% confidence interval = 143-166 versus 142 IU/dl, 95% confidence interval = 138-147; P = 0.045) and were more represented in individuals with high (> or = 150 IU/dl) FVIII:c levels (21.2 versus 10.8%; odds ratio = 2.27, 95% confidence interval = 1.17-4.39 after adjustment for age, blood group and high-sensitivity C-reactive protein levels). In conclusion, this clinical report suggests the common FVHR2 as a possible independent determinant of FVIII:c levels. The report concomitantly addresses the relationship between factor V and factor VIII levels and supports the hypothesis of a mild prothrombotic role of FVHR2 by means of increased factor VIII levels.  相似文献   
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OBJECTIVE: Sleep disturbances are frequent in Angelman syndrome (AS); however, beside the few studies which have investigated sleep disorders in AS by means of questionnaires, to our knowledge, no systematic polysomnographic recordings have been carried out in AS patients. The present study represents the first attempt to study sleep patterns of AS by polysomnography, to evaluate the influences of sleep on the paroxysmal electroencephalogram (EEG) patterns of AS and to assess the eventual age-related changes of sleep architecture and of sleep EEG abnormalities in children and adolescents with AS. METHODS: Fifteen children with AS (7 males and 8 females, mean age 7.2 years, range 3-16 years), attending the Sleep Center of the Department of Child Neurology and Psychiatry of the University of Rome 'La Sapienza' and the Sleep Research Centre of the Oasi Institute (IRCCS) of Troina were included and subdivided into two subgroups by age: subgroup 1, aged 3-5 years, and subgroup 2, aged 9-17 years. Two control groups of age-matched normal subjects were also included: one aged less than 8 years and another aged more than 8 years; additionally, two other groups of age-matched children with epilepsy and mental retardation of different origin, one aged less and one aged more than 9 years were taken into consideration. The statistical comparison between the sleep parameters obtained from the patients and those from the other groups was carried out by means of the non-parametric Kruskal-Wallis ANOVA and the Mann-Whitney U test. RESULTS: The most frequent EEG abnormality found in AS patients appeared to be the 2-3 c/s poorly defined spike/waves complexes. This pattern was influenced by sleep stages; the duration of the runs showed an increasing length with sleep deepening from sleep stage 1 to slow-wave sleep (SWS). Moreover, the 2-3 c/s bursts activity present in sleep stage 2 showed a slowing to 1-2 c/s during SWS. Regarding sleep architecture, in subjects with AS aged <8 year there was a significant reduction in sleep efficiency as compared to normal controls, while the percentage and duration of REM sleep was significantly lower and the percentage of SWS was significantly higher. REM sleep time was reduced in AS subjects aged >8 years than in normal controls. The comparison between AS groups and mental retardation with epilepsy groups did not show significant differences. CONCLUSIONS: Similarly to other types of genetically determined mental retardation syndromes, also subjects with AS seems to show important abnormalities of their sleep polysomnographic patterns. SIGNIFICANCE: This is the first study which reports, in detail, these abnormalities and opens a new path for further insight into the knowledge of additional sleep-related disturbances which are reported in sleep questionnaires by the caregivers of AS subjects.  相似文献   
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Idebenone (45 mg twice daily) was administered to 7 patients with moderate renal impairment (creatinine clearance 21-40 ml/min) for 10 days. Standard pharmacokinetic parameters were computed on day 1 (single administration) and on day 10. On day 1 the mean of the maximum plasma concentration values (C(max)) was 364 ng/ml (standard deviation (S.D.) 100); time to C(max) (t(max)) was in the range of 1-2 h for 6 patients and 12 h for the remaining patient: the mean was 3 h (S.D. 3.99); the mean area under the plasma concentration vs. time curve (AUC) was 3005 ng h/ml (S.D. 1152). On day 10 the mean C(max) was 531 ng/ml (S.D. 355.3), the mean t(max) was 0.07 h (S.D. 0.19), the mean AUC was 3167 ng/ml (S.D. 2944) and the mean elimination half-life (t(1/2)) was 4.9 h (S.D. 1.1). Idebenone metabolites (QS-4, QS-6 and QS-10) showed a kinetic profile similar to the parent compound, with pharmacokinetic parameters comparable to idebenone for QS-4 and lower than idebenone for QS-6 and QS-10. Idebenone was metabolized and easily excreted and no accumulation was observed for the compound and its metabolites. No significant modification of the biohumoral indexes and vital signs and no adverse reactions were observed.  相似文献   
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Overexpression of the hepatocyte growth factor receptor (Met/HGF receptor), a transmembrane tyrosine kinase encoded by the met proto-oncogene, has been associated with tumor progression in different human carcinomas. More recently, the Met/HGF receptor has also been described in tumor cell lines of mesenchymal origin, suggesting the existence of an autocrine loop that may contribute to the pathogenesis of sarcomas. In this study, we analyzed the expression of Met/HGF receptor by Western blotting and immunohistochemistry in frozen samples of 87 primary tumors of bone and soft tissues. Among benign tumors, overexpression was consistently found only in giant-cell tumor, a locally aggressive lesion that may also, although rarely, spread to the lung. Among malignant lesions, the presence of the Met/HGF receptor was detected in a relevant percentage of primaries and in almost all of the recurrences. The highest levels of Met/HGF receptor were found in osteosarcoma, a highly aggressive tumor that typically permeates the host bone and rapidly expands to the soft tissues. On the contrary, only low levels of Met/HGF receptor were found in chondrosarcoma, a slowly growing tumor that usually expands without massive destruction of the surrounding structures. These data indicate an association of Met/HGF expression with local aggressiveness in human mesenchymal tumors. The finding of Met/HGF receptor overexpression in all of the osteosarcomas suggests a role for the met proto-oncogene in the pathogenesis of this tumor.  相似文献   
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Experimental studies have demonstrated that the GABAergic system modulates acetylcholine release and, through GABAA receptors, tonically inhibits cholinergic activity. Little is known about the effects of GABA on the cholinergic activity in the human central nervous system. In vivo evaluation of some cholinergic circuits of the human brain has recently been introduced using a transcranial magnetic stimulation (TMS) protocol based on coupling peripheral nerve stimulation with TMS of the motor cortex. Peripheral nerve inputs have an inhibitory effect on motor cortex excitability at short intervals (short latency afferent inhibition, SAI). We investigated whether GABAA activity enhancement by lorazepam modifies SAI. We also evaluated the effects produced by lorazepam on a different TMS protocol of cortical inhibition, the short interval intracortical inhibition (SICI), which is believed to be directly related to GABAA activity. In 10 healthy volunteers, the effects of lorazepam were compared with those produced by quetiapine, a psychotropic drug with sedative effects with no appreciable affinity at cholinergic muscarinic and benzodiazepine receptors, and with those of a placebo using a randomized double-blind study design. Administration of lorazepam produced a significant increase in SICI  ( F 3,9= 3.19, P = 0.039)  . In contrast to SICI, SAI was significantly reduced by lorazepam  ( F 3,9= 9.39, P = 0.0002)  . Our findings demonstrate that GABAA activity enhancement determines a suppression of SAI and an increase of SICI.  相似文献   
7.
Background: Polydatin is a stilbenoid with important antioxidant, anti-inflammatory, and immunomodulating properties. The aim of this study was to assess the anti-inflammatory preventive effect of polydatin in the mouse model of acute arthritis induced by calcium pyrophosphate (CPP) crystals. Methods: Acute arthritis was induced by the injection of a suspension of sterile CPP crystals into the ankle joint of Balb/c mice. Animals were randomized to receive polydatin or colchicine (the control drug) according to a prophylactic and a therapeutic protocol. The primary outcome was the variation of ankle swelling obtained after crystal injection and treatment, while histological parameters such as leukocyte infiltration, IL-1ß and CXCL1 levels and tissue expression were considered as secondary outcomes. Results: Prophylactic treatment with PD significantly diminished ankle swelling after 48 h from crystal injection. Secondary outcomes such as leukocyte infiltration, necrosis, edema, and synovitis were also decreased. PD caused a reduction in circulating levels of IL-1ß and CXCL1, as well as their tissue expression. By contrast, the therapeutic administration of PD did not have any beneficial effect. Conclusions: PD can effectively prevent acute inflammatory response to crystals in the mouse model of CPP crystal-induced arthritis. These results suggest that this bioactive compound might be used in the prevention of crystal-induced acute attacks in humans.  相似文献   
8.
Background/PurposeMany studies on ex-preterm babies were conducted to evaluate their respiratory sequelae, but, to our knowledge, the condition described in this paper was never reported before and is not included in the classifications of thoracic anomalies proposed so far.MethodsClinical data and images of a novel thoracic deformity observed in the last 10 years are shown. This anomaly is characterized by an indentation of the ribs on both (less frequently one) anterolateral parts of the chest wall. All our patients with this condition were ex-preterm babies. We named this novel thoracic anomaly as “postprematurity thoracic dysplasia” (PPTD). Possible etiopathogenetic mechanisms and treatment options are discussed.ResultsWe observed 8 patients with variable range of respiratory symptoms. In 2 cases the malformation caused a severe functional restriction of lung volumes and surgery was performed to improve respiratory symptoms; in other cases the symptoms were mild or absent and the malformation was a matter of concern only for cosmesis.ConclusionsPPTD is a novel thoracic anomaly typical of ex-preterms. Clinical relevance is variable. In severe cases surgery can be considered.Level of evidenceIV.  相似文献   
9.
STUDY DESIGN: A case report. OBJECTIVES: To report and discuss a case of post-traumatic epidural hematoma of the craniocervical junction with concomitant brain stem infarction. SUMMARY OF BACKGROUND DATA: Post-traumatic epidural hematoma of the cervical spine and brain stem post-traumatic infarction are very rare disorders. Post-traumatic epidural hematoma is usually located dorsally in the epidural space. METHODS: The clinical, neuroradiologic, and neurophysiologic findings in one patient with post-traumatic epidural hematoma located ventrally at the cervicomedullary junction and associated with medial infarction at the pontomedullary junction are reported. RESULTS: The main clinical finding in this patient was bilateral corticospinal and corticobulbar tract involvement. A magnetic resonance image showed displacement and flattening of the medulla oblongata and of the most cranial portion of cervical cord, which were caused by the epidural hematoma associated with an ischemic lesion of the pontomedullary junction. Results of central motor conduction studies indicated that the abnormality of the central motor pathways was localized at brain stem level, and that there was normal conduction from the cervicomedullary junction to spinal cord. CONCLUSION: This is the first reported case of spinal epidural hematoma located ventrally in the cervical spine at the cervicomedullary junction level and concomitant infarction at the pontomedullary junction resulting from whiplash injury.  相似文献   
10.
New vessel formation is the result of the complex orchestration of various elements, such as cells, signalling molecules and extracellular matrix (ECM). In order to establish the suitable conditions for an effective cell response, the influence of vascular endothelial growth factor (VEGF) complexation with heparin sodium salt (Hp) on its pro-angiogenic activity has been evaluated by an in vitro capillary-like tube formation assay. VEGF with or without Hp was embedded into collagen gels, and the activated matrices were characterized in terms of VEGF activity and release kinetics. Taking into account the crucial role of Hp in VEGF stability and activity, VEGF/Hp complex was then encapsulated into microspheres based on poly(lactide-co-glycolide) (PLGA), and microsphere properties, VEGF/Hp release kinetics and VEGF in vitro activity over time were evaluated. Integrated microsphere/collagen matrices were developed in order to provide a continuous release of active VEGF/Hp inside the matrix but also a VEGF gradient at the boundary, which is an essential condition for endothelial cell attraction and scaffold invasion. The results confirmed a strong influence of Hp on VEGF configuration and, consequently, on its activity, while the encapsulation of VEGF/Hp complex in PLGA-microspheres guaranteed a sustained release of active VEGF for more than 30 days. This paper confirms the importance of VEGF stability and signal presentation to cells for an effective proangiogenic activity and highlights how the combination of two stabilizing approaches, namely VEGF/Hp complexation and entrapment within PLGA-based microspheres, may be a very effective strategy to achieve this goal.  相似文献   
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