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1.
Summary:  Purpose: To identify a specific neuropsychological profile associated with myoclonic astatic epilepsy (MAE) and Lennox-Gastaut syndrome (LGS).
Methods: Seven patients diagnosed with MAE and four patients diagnosed with LGS were selected from patients referred to our Child Neurology Unit. The patients were assessed both clinically (awake, sleep, Holter EEG, seizures frequency, and semiology) and neuropsychologically (IQ, language, attention, visuospatial and visuomotor abilities, and behavior). One representative case of each syndrome is presented here.
Results: The clinical picture of the MAE patient resembled that of an MAE condition associated with transitory epileptic encephalopathy. The neuropsychological findings suggest that electroclinical anomalies can temporarily affect cognitive and behavioral functioning. Early effective antiepileptic drug (AED) treatment was found to improve cognitive outcome. In contrast, LGS was associated with mental retardation, which persisted after seizure control.
Conclusions: At present, it remains difficult to delineate a precise neuropsychological profile associated with MAE and LGS. The cognitive outcome of MAE is variable and depends on the clinical pattern. With regard to LGS, the hypothesis of a genetic predisposition underlying both the epilepsy and the mental retardation is still valid. Alternatively, exposure to subclinical electrophysiological anomalies during a critical period of cerebral development may be responsible for the mental retardation. At the time the clinical manifestations appear, drug treatment, even if effective, would have only limited impact on cognitive outcome. However, early multidisciplinary intervention may help to improve behavior and communicative abilities, enhancing the quality of life of these children and their families.  相似文献   
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Gastric MALT lymphoma usually develops from chronic gastritis, the vast majority of which (>90%) is associated with Helicobacter pylori infection. We sequenced the third complementarity determining region (CDR3) of immunoglobulin heavy chain genes in 19 gastric MALT lymphoma clones to determine the pattern of variable (V), diversity (D) and joining (J) gene utilization during immunoglobulin gene rearrangement.
DNA was extracted from paraffin-embedded sections and the rearranged CDR3 regions were amplified using a semi-nested polymerase chain reaction (with primers complementary to the conserved framework-three segment of the variable region [FR3A] and J regions). The DNA used for cloning and sequencing was obtained after purification of monoclonal bands excised from polyacrylamide gels. The N-D-N region specific to each clone was compared with known germline D sequences.
Similarly to that observed in normal and leukaemic B cells, our series of gastric MALT lymphomas showed apparent preferential utilization of genes from the DXP family. In two cases no similarity between the CDR3 nucleotide sequences of the neoplastic clones and the known germline D sequences could be found. In 10/19 analysed alleles the lymphoma B-cell clones appeared to contain two D gene segments (D-D recombination), a rare occurrence in normal individuals but one which has been described as a significant event in the determination of idiotype expression and antigen-binding affinity. Remarkably, despite the use of different D and J segments, the resultant amino acid sequences matched in two patients, suggesting the presence of a common selecting antigen.
The observed pattern of D gene rearrangement suggests that MALT lymphoma B-cell clones have undergone antigen selection, which seems to indicate that the antigen stimulation plays a pivotal role in the development of the lymphoma.  相似文献   
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The main features of central 5-HT1 receptors   总被引:1,自引:0,他引:1  
The 5-HT1 receptor family comprises five different pharmacologic subtypes, designated 5-HT1A, 5-HT1B, 5-HT1C, 5-HT1D, and 5-HT1E, whose common property is to bind 5-HT with nanomolar affinity. Recent investigations with molecular biology approaches led to the cloning and sequencing of 5-HT1A receptors in the rat and in the human, and of the 5-HT1C receptor in the rat. Although the 5-HT1A and 5-HT1C protein binding subunits exhibit the same structure with seven hydrophobic transmembrane domains, an extracellular N terminal and an intracellular C tail, their respective amino-acid sequences are markedly different. Indeed, a higher degree of sequence homology is found between the 5-HT1C and 5-HT2 receptors than between the former and 5-HT1A receptors, suggesting that the 5-HT1C subtype in fact belongs to the 5-HT2 class of central 5-HT receptors. All other 5-HT1 receptor subtypes are negatively coupled to adenylyl cyclase, whereas the 5-HT1C subtype, like 5-HT2 receptors, is positively coupled to phospholipase C. The respective regional distributions and regulatory properties, as well as pending questions regarding the ultrastructural localization, synthesis, mutual interactions, and axonal flow of 5-HT1 receptor subtypes, are also discussed.  相似文献   
6.
One hundred eighty-one patients with measurable recurrent or metastatic colorectal cancer, who had not received prior chemotherapy, were randomized in a prospective controlled trial to receive 5-fluorouracil (5FU), 13.5 mg/kg, for five days (arm A) or high-dose folinic acid [Cyanamid-Lederle, Italy] (FA), 200 mg/m2, for five days and 5FU, 400 mg/m2 for five days (arm B). The treatments were repeated every four weeks. One hundred fifty-five patients were evaluable for response. The two arms were balanced for all potential prognostic factors studied. The response rate (CR+PR) was 18% in the 5FU arm and 16% in the 5FU plus FA arm. Median duration of response was 56 weeks for 5FU alone and 42 weeks for the combination (p = 0.48). Median time to failure (TTF) was 20 weeks for arm A and 21 for arm B (p = 0.62). Median survival was 62 weeks on the 5FU arm and 53 weeks on the FA plus 5FU arm (p = 0.14). Dose intensity (DI) delivered was the same in both arms. Diarrhea and mucositis were the most frequent adverse reactions in arm B; 20% of the patients in arm A and 38% of those in arm B experienced diarrhea (p = 0.008). Mucositis occurred in 34% of patients in arm A and 42% in arm B (p = 0.04). In general nausea and vomiting were moderate. Hematological toxicity was more severe in patients treated with 5FU alone: 31% in arm A and 14% in arm B developed leukopenia (p = 0.015). In the combination arm one patient died due to gastrointestinal and hematological toxicity after the seventh cycle. This study indicates that, in advanced colorectal cancer, the combination of high-dose FA and 5FU is not superior to 5FU alone when utilized at standard high-dose intensity.  相似文献   
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In situ hybridization in conjunction with three-dimensional reconstruction was used to examine the topology of satellite DNA (sDNA) sequences in hippocampal CA1 neurons. In slices fixed immediately after preparation, 4-5 signals/nucleus were detected in CA1, CA3 and dentate neurons. 70-80% of 154 neurons examined in these 3 areas displayed all signals at the nuclear periphery. In the remaining fraction of neurons, sDNA signals were divided between the nucleolus and the nuclear periphery. sDNA signals were consistently localized to the nuclear midplane. Slices left to equilibrate in artificial cerebral spinal fluid for 1 h, in the absence of potentiation, exhibited a significant increase in the total number of signals/nucleus in CA1 and dentate neurons. This increase in the number of signals occurred in both nucleolar and peripheral compartments, with the number of the nucleolar compartment nearly doubling. The total number of signals/nucleus was found to be consistently reduced in tetanized CA1 neurons (4.89 +/- 0.09 signals/nucleus, n = 195, P less than 0.05) as compared to neurons from unpotentiated slices (5.27 +/- 0.10 signals/nucleus, n = 81). A similar decrease in the total number of signals/nucleus was also observed in CA1 neurons exposed to N-methyl-D-aspartate (NMDA), from 5.27 +/- 0.10 signals/nucleus (n = 81) to 5.00 +/- 0.08 signals/nucleus (n = 215, P less than 0.05). In contrast, dentate neurons, employed as internal controls, did not exhibit any change in number and compartmentalization of sDNA signals.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
Treatment of metastatic malignant melanoma with dacarbazine plus tamoxifen.   总被引:8,自引:0,他引:8  
BACKGROUND. Endocrine factors may affect the clinical course of malignant melanoma and the response to the treatment of this disease. The presence of estrogen receptors in melanomas has been suggested, and occasional responses to antiestrogen therapy have been reported. METHODS AND RESULTS. We randomly assigned 117 patients with metastatic malignant melanoma to treatment with dacarbazine alone or dacarbazine in combination with tamoxifen. The overall rate of response, measured objectively, was higher (28 percent vs. 12 percent, P = 0.03) and survival was longer (median, 48 vs. 29 weeks, P = 0.02) among the patients who received dacarbazine plus tamoxifen than among those who received dacarbazine alone. Among women, both the response rate (38 percent vs. 10 percent, P = 0.04) and the median survival (69 vs. 30 weeks, P = 0.008) were better with dacarbazine plus tamoxifen than with dacarbazine alone, whereas among men the differences were smaller and not statistically significant. Among the patients given dacarbazine alone, there were no significant differences between women and men in response rate (10 percent vs. 13 percent) or survival (30 vs. 27 weeks), whereas among those given dacarbazine plus tamoxifen, women had better outcomes, as indicated by both response rate (38 percent vs. 19 percent, P = 0.15) and survival (69 vs. 31 weeks, P = 0.02). When we analyzed the Quetelet body-mass index (the weight in kilograms divided by the square of the height in meters) as an indirect indicator of the levels of endogenous estrogens in postmenopausal women and in men, survival was not affected by the body-mass index in the group given dacarbazine alone, whereas in the group given dacarbazine plus tamoxifen, survival was longer among patients whose Quetelet index was above the median value than among those with a Quetelet index lower than the median value (60 vs. 26 weeks, P less than 0.001). CONCLUSIONS. In the treatment of metastatic malignant melanoma, dacarbazine plus tamoxifen is more effective than dacarbazine alone, as indicated by both the response rate and the median survival; the difference in efficacy is among women.  相似文献   
9.
Several genes with an essential role in the regulation of eating behavior and body weight are considered candidates involved in the etiology of eating disorders (ED), but no relevant susceptibility genes with a major effect on anorexia nervosa (AN) or bulimia nervosa (BN) have been identified. Brain-derived neurotrophic factor (BDNF) has been implicated in the regulation of food intake and body weight in rodents. We previously reported a strong association of the Met66 allele of the Val66Met BDNF variant with restricting AN (ANR) and low minimum body mass index in Spanish patients. Another single nucleotide polymorphism located in the promoter region of the BDNF gene (-270C>T) showed lack of association with any ED phenotype. In order to replicate these findings in a larger sample, we performed a case-control study in 1142 Caucasian patients with ED consecutively recruited in six different centers from five European countries (France, Germany, Italy, Spain and UK) participating in the 'Factors in Healthy Eating' project. We have found that the Met66 variant is strongly associated to all ED subtypes (AN, ANR, binge-eating/purging AN and BN), and that the -270C BDNF variant has an effect on BN and late age at onset of weight loss. These are the first two variants associated with the pathophysiology of ED in different populations and support a role for BDNF in the susceptibility to aberrant eating behaviors.  相似文献   
10.
Two patients affected with two different forms of Osteogenesis Imperfecta were examined in order to study collagen and glycosaminoglycans (GAGs) in skin and iliac crest cartilage. A sharp decrease of the galactosamine to glucosamine ratio due to a reduced content of chondroitin sulfate was evidenced in both patients. Moreover the structure of proteoglycans appeared altered, this being more evident in the severe form of the disease. Morphological examination in light and electron microscopy of cartilage of the less severely diseased patient showed that GAGs in the extracellular matrix did not present regular connection with collagen fibers. Chondrocytes, elongated and disorderly scattered, showed large lipidic inclusions and, on histochemical basis, were devoid of UDPG dehydrogenase activity. Treatment with (+)-catechin produced an improvement, in both patients, of the biochemical pattern of collagen and GAGs. Similarly a shift of the cellular activity and of the matrix morphology towards normality was observed in the investigated cartilage of the less severely affected patient.  相似文献   
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