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61.
Magnetic resonance imaging (MRI) is the current gold standard for the diagnosis of brain tumors. However, despite the development of MRI techniques, the differential diagnosis of central nervous system (CNS) primary pathologies, such as lymphoma and glioblastoma or tumor‐like brain lesions and glioma, is often challenging. MRI can be supported by in vivo magnetic resonance spectroscopy (MRS) to enhance its diagnostic power and multiproject‐multicenter evaluations of classification of brain tumors have shown that an accuracy around 90% can be achieved for most of the pairwise discrimination problems. However, the survival rate for patients affected by gliomas is still low. The High‐Resolution Magic‐Angle‐Spinning Nuclear Magnetic Resonance (HR‐MAS NMR) metabolomics studies may be helpful for the discrimination of gliomas grades and the development of new strategies for clinical intervention. Here, we propose to use T2‐filtered, diffusion‐filtered and conventional water‐presaturated spectra to try to extract as much information as possible, fusing the data gathered by these different NMR experiments and applying a chemometric approach based on Multivariate Curve Resolution (MCR). Biomarkers important for glioma's discrimination were found. In particular, we focused our attention on cystathionine (Cyst) that shows promise as a biomarker for the better prognosis of glioma tumors.  相似文献   
62.
OBJECTIVE: To report on clinical features, comorbidity, and response to pharmacotherapy in children and adolescents with obsessive-compulsive disorder (OCD) naturalistically followed and treated with serotonin reuptake inhibitors (SRIs). METHOD: A consecutive series of 94 patients (65 males, 29 females, age 13.6 +/- 2.8 years), referred in the period January 2001-April 2004, diagnosed with a clinical interview (Diagnostic Interview for Children and Adolescents-Revised), and followed for 10 +/- 6 months, were included in the study. RESULTS: Contamination obsessions and washing rituals were associated with less impairment than other subtypes of OCD. Aggressive sexual obsessions and checking rituals as well as symmetry obsessions and ordering-repeating rituals were more frequently comorbid with tic disorders. According to the Clinical Global Impressions-Improvement scale (score 1 or 2), 63 subjects (67%) were responders to treatment. Nonresponders were more severely impaired and had a higher number of comorbid disorders, namely, bipolar disorder and conduct disorder (p < .05). Forty-seven patients (50%) received an SRI monotherapy, whereas the other 47 (50%) needed other medications. Patients receiving SRI monotherapy were less severely impaired; had a later onset of OCD; were at a younger age at the visit, had higher rates of depression and anxiety and lower rates of bipolar disorder, attention-deficit/hyperactivity disorder, and conduct disorder (p < .05). CONCLUSIONS: Long-term naturalistic prospective studies in pediatric patients with OCD might represent an important source of information for everyday care regarding the effectiveness of a treatment over extended periods of time under routine clinical conditions.  相似文献   
63.
This study was designed to calculate the critical velocity (vcrit) and anaerobic distance capacity (ADC) of prepubescent children for running events. Thirty-four prepubertal children underwent a graded field test to exhaustion in order to determine peak oxygen uptake (peak VO2) and maximal aerobic velocity (MAV). Then, in random order, they performed five runs to exhaustion (tlim) at relative velocities corresponding to 90, 95, 100, 105, and 110% of MAV. The linear relationships between distance limit (dlim) and tlim were calculated in order to determine vcrit (slope of the relationship) and ADC (intercept). Very high individual coefficients of determination were found between dlim and tlim (0.98 < r2 < 0.99; p < 0.001). The vcrit was significantly correlated with peak VO2 (r = 0.73; p < 0.001). However, no relationship was found between ADC and the maximal accumulated oxygen deficit. In conclusion, our results indicated that, for children, the relationship between dlim and tlim could be calculated with tlim ranging from 2 to 10 min, and that vcrit is a good indicator of the aerobic fitness of children. Nevertheless, further studies will have to be conducted to validate the use of ADC as an indicator of children's anaerobic capacity.  相似文献   
64.
Trypanosoma cruzi, the flagellate protozoan which is the causative agent of the American trypanosomiasis, Chagas disease has carboxypeptidase activity. The enzyme has been purified to protein homogeneity, and shown to be a lysosomal monomeric glycoprotein with a molecular mass of about 54kDa. The enzyme has an optimum acidic pH (4.5 with furyl acryloyl-Phe-Phe as substrate), is highly specific for hydrophobic C-terminal amino acid residues, and is strongly inhibited by 3,4-dichloroisocoumarin (IC(50) value 0.3 microM). The enzyme is encoded by a number of genes arrayed in head-to-tail tandems; one of these genes has been cloned and sequenced. Sequence comparisons indicate that the enzyme belongs to the C group of serine carboxypeptidases, within the S10 serine peptidase family, and shows the higher similarity to plant and yeast enzymes. The residues involved in catalysis and most of those involved in substrate binding are conserved in the T. cruzi enzyme as well as 8 out of 10 Cys residues known to be involved in disulfide bridges in the yeast enzyme. This is the first report of an S10 family enzyme in trypanosomatids. The presence of serine carboxypeptidases is not restricted to T. cruzi, being possibly a general character of trypanosomatids.  相似文献   
65.
Smith  DK; Gilula  LA; Amadio  PC 《Radiology》1990,176(2):497-499
Excessive dorsiflexion (dorsal tilting) of the lunate on a lateral wrist radiograph can be an important sign of carpal injury. Lunate dorsiflexion is a well-recognized sign of an intercarpal ligamentous injury pattern known as dorsal intercalated segment instability (DISI). It is less well recognized that excessive dorsal tilting of the lunate (DISI configuration) can also be produced by displacement of a scaphoid waist fracture. Since the management and prognosis of displaced scaphoid fractures may be quite different from those for nondisplaced fractures, radiologists can make an important contribution by recognizing dorsal tilting of the lunate and appreciating that it may be an important, indirect sign of scaphoid fracture displacement, which may not be directly visualized with standard wrist radiography. In this setting, computed tomography or complex motion tomography may be helpful for further evaluation of the scaphoid fracture.  相似文献   
66.
Lung carcinoids occur sporadically and rarely in association with multiple endocrine neoplasia type 1 (MEN1). There are no well defined genetic abnormalities known to occur in these tumors. We studied 11 sporadic lung carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene were inactivated. All four tumors showed the presence of a MEN1 gene mutation and loss of the other allele. Observed mutations included a 1 bp insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide substitution affecting a donor splice site. Each mutation predicts truncation or potentially complete loss of menin. The remaining seven tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH. The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a complex germline MEN1 gene mutation. The data implicate the MEN1 gene in the pathogenesis of sporadic lung carcinoids, representing the first defined genetic alteration in these tumors.   相似文献   
67.
As more mutations are identified in genes of known sequence, there is a crucial need in the areas of medical genetics and genome analysis for rapid, accurate and cost-effective methods of mutation detection. We have developed a multiplex allele-specific diagnostic assay (MASDA) for analysis of large numbers of samples (> 500) simultaneously for a large number of known mutations (> 100) in a single assay. MASDA utilizes oligonucleotide hybridization to interrogate DNA sequences. Multiplex DNA samples are immobilized on a solid support and a single hybridization is performed with a pool of allele-specific oligonucleotide (ASO) probes. Any probes complementary to specific mutations present in a given sample are in effect affinity purified from the pool by the target DNA. Sequence-specific band patterns (fingerprints), generated by chemical or enzymatic sequencing of the bound ASO(s), easily identify the specific mutation(s). Using this design, in a single diagnostic assay, we tested samples for 66 cystic fibrosis (CF) mutations, 14 beta-thalassemia mutations, two sickle cell anemia (SCA) mutations, three Tay-Sachs mutations, eight Gaucher mutations, four mutations in Canavan disease, four mutations in Fanconi anemia, and five mutations in BRCA1. Each mutation was correctly identified. Finally, in a blinded study of 106 of these mutations in > 500 patients, all mutations were properly identified. There were no false positives or false negatives. The MASDA assay is capable of detecting point mutations as well as small insertion or deletion mutations. This technology is amenable to automation and is suitable for immediate utilization for high-throughput genetic diagnostics in clinical and research laboratories.   相似文献   
68.
Proliferative expansion and apoptotic cell death play prominent roles in T cell development. The molecular control of cell cycle progression and apoptosis appear to be inter-connected since the Bcl-2 protein can inhibit apoptosis and slow cell cycle progression in cortical thymocytes and mature T cells, particularly during the transition from the quiescent state into the cell cycle. Here the impact of bcl-2 transgene expression on CD3-CD4-CD8- T cell progenitors was assessed. Bcl-2 enhanced the survival of these progenitors at all of the four major differentiation stages, CD25- CD44+ (pro-T1), CD25 + CD44+ (pro- T2), CD25 + CD44- (pro-T3) and CD25-CD44- (pro-T4). However, it reduced cell cycling and slowed turnover only in the pro-T4 subset. From an analysis of bcl-2 transgenic mice expressing a TCR transgene or bearing a mutation in the scid or rag-1 gene we conclude that Bcl-2 inhibits proliferation only of T cell progenitors that are activated via the pre- TCR, not those stimulated via c-Kit and the IL-7 receptor.   相似文献   
69.
Clerodendrum umbellatum Poir (Verbenaceae) is traditionally used in Cameroon for the treatment of many diseases including intestinal helminthiasis. This study was undertaken to assess the in vivo antischistosomal activity of its leaves aqueous extract on a Schistosoma mansoni mice model and to determine the most effective dose of this extract. Mice showing a patent infection of S. mansoni were daily treated with C. umbellatum leaves aqueous extract at the doses of 40, 80 or 160 mg/kg body weight for 14 days. Seven days after administration of the extract, schistosomicidal activity was evaluated on the liver and spleen weights, faecal eggs releasing, liver egg count and worm burden. Treatment using C. umbellatum leaves aqueous extract resulted in an important reduction in faecal egg output by 75.49 % and 85.14 % for 80 mg/kg and 160 mg/kg of the extract respectively. These reduction rates did not differ significantly from the 100 % obtained in the group of infected mice treated with 100 mg/kg of praziquantel. C. umbellatum leaves aqueous extract was lethal to S. mansoni worm. A 100 % reduction rate was recorded in the group of infected mice treated with 160 mg/kg of the extract, as well as in praziquantel-treated mice. An amelioration of the hepatosplenomegaly was noticed in both the extract-treated mice and the praziquantel-treated mice. From these results, we can conclude that C. umbellatum leaves aqueous extract demonstrated schistosomicidal properties in S. mansoni model at doses of at least 80 mg/kg body weight.  相似文献   
70.
Spinocerebellar ataxia type 1 (SCA1) is an autosomal dominant neurodegenerative disorder caused by the expansion of a CAG trinucleotide repeat which encodes glutamine in the novel protein ataxin-1. In order to characterize the developmental expression pattern of SCA1 and to identify putative functional domains in ataxin-1, the murine homolog (Sca1) was isolated. Cloning and characterization of the murine Sca1 gene revealed that the gene organization is similar to that of the human gene. The murine and human ataxin-1 are highly homologous but the CAG repeat is virtually absent in the mouse sequence suggesting that the polyglutamine stretch is not essential for the normal function of ataxin-1 in mice. Cellular and developmental expression of the murine homolog was examined using RNA in situ hybridization. During cerebellar development, there is a transient burst of Sca1 expression at postnatal day 14 when the murine cerebellar cortex becomes physiologically functional. There is also marked expression of Sca1 in mesenchymal cells of the intervertebral discs during development of the spinal column. These results suggest that the normal Sca1 gene, has a role at specific stages of both cerebellar and vertebral column development.   相似文献   
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