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991.
Autosomal recessive primary microcephaly (MCPH) is a rare neurodevelopmental disorder characterized by mental retardation and congenital microcephaly with a head circumference at least 4 SD below age and sex means, in the absence of other significant malformations or neurological deficits. Truncating alterations in the MCPH1 gene have previously been shown to exhibit a distinct cellular phenotype, with a high proportion of prophase-like cells (>10%) due to premature chromosome condensation in early G2- and delayed decondensation in early G1-phase of the cell cycle. We report here the first patient with a homozygous substitution of a highly conserved threonine residue by an arginine (c.80C>G, Thr27Arg) localized in the N-terminal BRCT domain of MCPH1. The cellular and clinical phenotype of this patient is much less pronounced than that of previously described patients with truncating alterations in the MCPH1 gene. Firstly, the fraction of prophase-like cells accounts for just 3-4% of the cell population. Secondly, clinically, he has only a very mild mental retardation with predominantly delayed motor skills but normal verbal IQ attainment. Additionally, head circumference was less severely affected, being -2.4 SD at birth and -3 SD at the age of six years. This justifies reconsideration and widening of the clinical phenotype definition of MCPH1.  相似文献   
992.
The aim of this study was to evaluate the parasitemia variation of three Hepatozoon species in Brazilian snakes. This study was conducted between 2001 and 2003 and included Hepatozoon terzii from Boa constrictor amarali, and Hepatozoon migonei and Hepatozoon cyclagrasi from Hydrodynastes gigas. It was observed that the parasitemia tended to decrease in all three Hepatozoon species but the parasites were not eliminated. This data suggest that Hepatozoon infection may be similar to Toxoplasma gondii infection, in that it persists throughout host life.  相似文献   
993.
Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is a fatal autosomal recessive disorder seen in infants. It is characterized by lower motor neuron degeneration, progressive muscle paralysis and respiratory failure, for which no effective treatment exists. The phenotype of neuromuscular degeneration (nmd) mice closely resembles the human SMARD1. The identification of the mutated mouse gene in nmd mice, Ighmbp2, led to the discovery of mutations of the homologous gene in humans with SMARD1. We have studied the nmd mouse model with in vivo electrophysiological techniques and evaluated the efficacy of Mab2256, a monoclonal antibody with agonist effect on the tyrosine kinase receptor C, trkC, on disease progression in nmd mice. Treatment with Mab2256 resulted in a significant but transient improvement of muscle strength in nmd mice, as well as normalization of the neuromuscular depression during high-frequency nerve stimulation. These results suggest the potential of using monoclonal agonist antibodies for neurotrophin receptors in lower motor neuron diseases such as SMARD1.  相似文献   
994.
Fluorescence in situ hybridization (FISH) analyses were performed on supernumerary marker chromosomes (SMCs) detected in 43,273 prenatal diagnoses over a period of 11 years, 1993-2003. A total of 42 pregnancies with SMC were identified, indicating a prevalence of one in 1032. A total of 15 SMCs were endowed with detectable euchromatin (prevalence, 1/2884), including six SMCs containing the cat eye critical region (CECR) on chromosome 22q11.21 (1/7212). De novo SMCs were found in 29 pregnancies (1/1492), including 14 euchromatic SMCs (48.2%). Follow-up studies were available for 24 cases. Nine pregnancies (37.5%) were terminated; two children (8.3%) were born with Pallister-Killian syndrome and cat eye syndrome (CES), respectively; 13 children (54.1%) showed apparently normal development. Familial SMCs were identified in 13 pregnancies (1/3328) from 11 unrelated women. They were all acrocentric. In all, 10 were heterochromatic and one was an extra der(22)t(11;22) chromosome. A total of 12 cases were available for follow-up. One pregnancy was terminated due to anhydramnios, spina bifida, and cystic-dysplastic kidneys; one child suffered from a der(22) syndrome; 10 children (83.3%) appeared unaffected. Studies for uniparental disomy were performed on seven pregnancies and revealed a case of maternal heterodisomy for chromosome 22. So far this is the largest FISH study of prenatally ascertained SMCs and the first study with detailed data on the prevalence. Findings illustrate the spectrum and clinical outcomes of prenatally diagnosed SMCs, and indicate a higher frequency of SMCs than generally assumed.  相似文献   
995.
The German short version of "Profile of Mood States" (POMS) was psychometrically tested in a representative sample (1009 subjects in Eastern Germany and 1034 subjects in Western Germany). The 35 items (7 point scale, instruction "How you have been feeling during the past 24 hours?") form the following scales: Depression/Anxiety, Fatigue, Vigor, Hostility. The POMS appears to be an internally consistent instrument (Cronbach's Alpha from 0.89 to 0.95). Replication of the postulated 4 factors was limited. There are hints for convergent validity of POMS-Scales using two questions: "1. Over the past two weeks, have you felt down, depressed, or helpless?" and "2. Over the past two weeks, have you felt little interest or pleasure in doing things?"  相似文献   
996.
Monocyte migration through the disrupted cerebral endothelial cell (EC) junctions plays an essential role in formation of multiple sclerosis (MS) demyelinating lesions. During pathogenesis of MS, activated ECs release endothelial microparticles (EMP), which possibly facilitate transendothelial migration (TEMIG) of monocytes. To assess functional roles of EMP in MS, specifically, their (i) interaction with monocytes, (ii) effect on monocyte TEMIG in an in vitro model of the brain microvascular endothelial cells (BMVEC), (iii) phenotypic profiles of EMP elicited by MS plasma and (iv) the effects of IFN-beta 1b on release of EMP and on TEMIG of monocytes (mono) and monocytes:EMP complexes (mono:EMP) through the BMVEC. The effect of IFN-beta 1b on the release of EMP and the TEMIG of mono and mono:EMP was assessed by preincubating BMVEC cultures of IFN-beta 1b prior to addition of plasma. Three EMP phenotypes, CD54, CD62E and CD31 were assayed. Plasma specimens from 20 patients with relapsing remitting MS (11 in exacerbation, MS-E, and 9 in remission, ME-R) and 10 healthy controls were studied. Incubation of BMVEC with MS-E plasma yielded elevated levels of EMPCD54, EMP62E and EMPCD31 relative to MS-R and control plasmas. MS-E but not MS-R or control plasma also augmented TEMIG of monocytes, respectively. Mono:EMP complexes further augmented TEMIG relative to mono alone, but only in the presence of MS-E plasma; there was no significant effect with MS-R or control plasmas. The presence of IFN-beta 1b inhibited TEMIG of mono and mono:EMP by 20% and 30%, respectively. MS-E but not MS-R plasma elicited release of activation-derived EMP and enhanced TEMIG of mono and mono:EMP. IFN-beta 1b inhibited TEMIG and release of EMP, suggesting a role of EMP and a novel therapeutic mechanism for IFN-beta 1b in MS.  相似文献   
997.
Clinical usefulness of the Parkinson's disease sleep scale   总被引:4,自引:0,他引:4  
OBJECTIVE: To test the usefulness of the Parkinson's disease sleep scale (PDSS) in identifying sleep disorders in the clinical practice setting. METHODS: Sixty-two PD patients were evaluated with the PDSS and the Epworth sleepiness scale (ESS). A cut-off of less than five for each PDSS item as an indicator of substantial sleep disturbance was chosen. If the ESS was equal to or greater than eight, patients were referred to a sleep disorder specialist and possible polysomnography. RESULTS: The mean total PDSS score was 104.7+/-21.5,which correlated with the mean Hoehn and Yahr score (1.9+/-0.9) as well as the mean ESS score (9.7+/-4.7). A significant correlation was also found between the ESS score and several items of the PDSS. CONCLUSIONS: The PDSS was useful in identifying sleep disturbances which were not previously diagnosed, such as sleep maintenance insomnia and excessive daytime sleepiness. Problems with the PDSS include ambiguities of some questions, lack of quantification and an inability to identify specific sleep disturbances such as sleep apnea.  相似文献   
998.
INTRODUCTION: This study examined the reproductive function and prevalence of polycystic ovary syndrome (PCOS) in women with bipolar disorder taking antimanic medications. METHOD: Women aged 18-45 treated for bipolar disorder and not taking steroid contraceptives were recruited to complete questionnaires about their menstrual cycle and to provide blood samples for measurement of a range of reproductive endocrine and metabolic hormone levels. Eighty women participated in completing the questionnaires and 72 of them provided blood samples. RESULTS: Fifty-two of the 80 women (65%) reported current menstrual abnormalities, 40 of which (50%) reported one or more menstrual abnormalities that preceded the diagnosis of bipolar disorder. Fifteen women (38%) reported developing menstrual abnormalities since treatment for bipolar disorder, 14 of which developed abnormalities since treatment with valproate (p = 0.04). Of the 15 patients reporting menstrual abnormalities since starting medication, 12 (80%) reported changes in menstrual flow (heavy or prolonged bleeding) and five (33%) reported changes in cycle frequency. No significant differences were observed between women receiving or not receiving valproate in mean levels of free or total serum testosterone levels. This was true for the total sample and for the sub-group without preexisting menstrual problems. However, within the valproate group, duration of use was significantly correlated with free testosterone levels (r = 0.33, p = 0.02). Three of the 50 women (6%) taking VPA, and 0% of the 22 taking other antimanic medications, met criteria for PCOS (p = 0.20). Other reproductive and metabolic values outside the normal range across treatment groups included elevated 17 alpha-OH progesterone levels, luteinizing hormone: follicle-stimulating hormone ratios, homeostatic model assessment (HOMA) values, and low estrogen and dehydroepiandrosterone sulfate (DHEAS) levels. Preexisting menstrual abnormalities predicted higher levels of 17 alpha-OH progesterone, free testosterone, and estrone as well as development of new menstrual abnormalities. Body mass index (BMI) was significantly positively correlated with free testosterone levels and insulin resistance (HOMA) across all subjects, regardless of medication used. CONCLUSIONS: Rates of menstrual disturbances are high in women with bipolar disorder and, in many cases, precede the diagnosis and treatment for the disorder. Treatment with valproate additionally contributes significantly to the development of menstrual abnormalities and an increase in testosterone levels over time. A number of bipolar women, regardless of type of medication treatment received, have reproductive and metabolic hormonal abnormalities, yet the etiology of such abnormalities requires further study. Women with preexisting menstrual abnormalities may represent a group at risk for development of reproductive dysfunction while being treated for bipolar disorder.  相似文献   
999.
Emergency physicians must often make assessments of complex hemodynamic parameters. To assess the utility of impedance cardiography (ICG) in the emergency department, the authors examined treating physicians' abilities to assess stroke volume (SV), cardiac output (CO), and systemic vascular resistance (SVR) by comparing the clinicians' estimates of these values to ICG measurements. Treating physicians were asked to estimate the SV, CO, and SVR of acutely ill patients as being low, normal, or high. ICG measurements of SV, CO, and SVR were also categorized as low, normal, or high. Physician estimates were compared with ICG measures for concordance. Changes of therapy initiated as a result of discordance between physician's estimates and ICG measurements were recorded. The treating physician assessments and ICG hemodynamic measurements were concordant in 62 of 101 (62%) cases for SV (kappa=0.068), in 53 of 101 (53%) cases for CO (p=0.125), and in 50 of 101 (50%) measurements for SVR (p=0.148). The low concordance suggests that treating physicians did not consistently estimate SV, CO, and SVR accurately. ICG provides noninvasive hemodynamic measurements of SV, CO, and SVR that offer clinical utility and potential value in the emergency department.  相似文献   
1000.
The isolated form of femoral bowing is an important differential diagnosis of campomelia. Therefore, knowledge of isolated anomalies is fundamental for prenatal diagnosis, especially for the differential diagnosis from severe syndromes. Four cases are presented to discuss the differential diagnosis of femoral bowing including a review of the literature. We report four newborn babies with unilateral bowing and shortening of the femur. Three had no further anomaly; one child had additional abnormalities due to coumarin embryopathy. The radiological findings were shortened femora with bowing and varus deformity and cortical thickening on the concave side. All other parts showed normal bone structure. The aetiology of femoral bowing is unknown. Early damage of the cartilaginous model followed by remodelling with thickening on the concave side of the bone similar to the healing of malaligned fractures is suspected. The isolated form of femoral bowing without any other anomalies has to be differentiated from complex and more often severe congenital syndromes such as campomelia. Postpartum radiological examination should be reduced to a single exposure of the affected limb and follow-up should be done by clinical examination.  相似文献   
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