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991.
Early onset of absence seizures (<3 years) is rare and usually associated with a poor cognitive prognosis. Familial cases have not been reported to date. We observed a family in which two out of three sibs showed early-onset absences and mild mental retardation. Linkage to the ECA1 locus, where one clinical subtype of CAE is mapped, was excluded by haplotype analysis. Direct sequencing of the candidate genes CLCN2 ,GABRG2 and CHRNA4 showed no mutations. We suggest the possibility of a specific epileptic syndrome with a putative AR inheritance. Further report of affected patients might allow a better classification.  相似文献   
992.
Hereditary neuroblastoma in a pair of identical twins is reported. In one of the twins the tumor occurred in fetal life and caused death of the twin before birth; in the other one, the tumor occurred at two months of life as IV-S neuroblastoma in the liver with primary tumor undetected. The unusual clinical course of the latter case is described: twice there was tumor regression, but in spite of treatment, fatal uncontrolled growth occurred. The family history, characterized by neoplasms of dissimilar cell types but without additional cases of neuroblastoma, is also detailed.  相似文献   
993.
Sardinian alcohol non-preferring (sNP) rats, selected for their low ethanol preference and consumption, carry a point mutation (R100Q) in the gene coding for GABA(A) receptor alpha(6) subunit, which becomes more sensitive to diazepam-evoked GABA currents. We performed binding studies in the cerebellum of normal (RR) and mutated (QQ) sNP rats using [3H]Ro 15-4513, an inverse agonist for the benzodiazepine site which binds both diazepam insensitive and diazepam sensitive sites. Saturation curves performed on cerebellar membrane from genotyped rats indicated an higher affinity of [3H]Ro 15-4513 for GABA(A) receptors in QQ with respect to RR rats (K(d) values 4.0+/-0.67 and 6.24+/-0.95 nM, respectively), with similar B(max) values (3.5+/-0.25 and 3.9+/-0.39 pmol/mg protein, respectively). Diazepam displacement curves showed a two component model for both genotypes, with similar K(i1) values for QQ and RR (3.6+/-0.62 and 4.9+/-0.33 nM, respectively). In QQ rats diazepam is able to completely displace [3H]Ro 15-4513 (K(i2)=1.48+/-0.27 microM), while in RR rats the diazepam sensitive sites are still present (K(i2)>10 microM). The basal mRNA and protein expression level of the alpha(6) subunit were similar in RR and QQ rats. The electrophysiological profile of oocytes of Xenopus laevis injected with cerebellar synaptosomes showed that ethanol positively modulated GABA-evoked currents significantly more in QQ than in RR rats. These data contribute to the characterization of the function of GABA(A) alpha(6) subunit and its involvement in determining alcohol related behavior.  相似文献   
994.

Background

Advances in comprehension of molecular biology of glioblastoma (GBM) have led to the development of targeted therapies. The aim of the present study was to evaluate the efficacy and safety of a targeted therapeutic approach in which administration of bevacizumab and erlotinib was tailored on the molecular profile of recurrent GBM.

Methods

We prospectively enrolled ten adult patients suffering from recurrent GBM who had undergone surgical resection and standard chemo-radiotherapy. Tumor tissue was assessed for the expression of EGFRvIII and MGMT promoter methylation by RT-PCR, and for PTEN and VEGF expression by immunohistochemistry. Normal PTEN status was required for inclusion. Patients with VEGF overexpressing tumors (10/10) were treated with bevacizumab (10 mg/kg iv every 2 weeks in 6-week?cycles); patients whose tumor expressed EGFRvIII (4/10) added erlotinib (150 mg/day orally; 300 mg/day if on enzyme-inducing antiepileptic drugs). Therapy was continued until disease progression or unacceptable toxicity. Primary endpoints of the study were response rate (RR), 6-month progression-free survival (PFS-6), and safety profile.

Results

The RR and PFS-6 were 100 % (4/4) and 50 % (3/6) in patients treated with bevacizumab+erlotinib (n?=?4) and bevacizumab (n?=?6), respectively. In the whole cohort (n?=?10), RR and PFS-6 were both 70 % (7/10); median PFS and overall survival (OS) were 8.0 (3.0–31.0) and 9.5 (5.0–31.0) months, respectively. No grade 3/4 adverse events were observed; three patients treated with bevacizumab+erlotinib displayed grade 1/2 rash not requiring dose reduction; one patient treated with bevacizumab developed intratumoral hemorrhage requiring treatment discontinuation.

Conclusion

To our knowledge, this is the first study on recurrent GBM in which administration of bevacizumab and erlotinib was tailored on the molecular profile of the patient’s tumor. Although we treated a limited number of patients, we obtained significantly higher RR and PFS-6 than those reported in a previous trial lacking molecular tumor analysis.  相似文献   
995.

Objective

The aim of our study was to determine the role of fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) and indium-111 Octreotide single photon emission tomography (111In-Octreotide SPECT) in the evaluation of metastatic medullary thyroid carcinoma (MMTC).

Methods

Twenty-five MMTC patients were retrospectively evaluated. All patients had undergone whole-body 18F-FDG-PET/CT including 20 who had also undergone 111In-Octreotide SPECT within a maximum interval of 6 weeks. Diagnostic contrast-enhanced computed tomography (CT) alone or as part of 18F-FDG-PET/CT examination was performed in all patients.

Results

Contrast-enhanced CT detected a total of 131 lesions including 79 enlarged lymph nodes and 14 bone lesions. 18F-FDG-PET/CT visualized a total of 92 true positive lesions (SUVmax range 1.1–10.0, mean 4.0 ± 1.7) including 66 lymph nodes, 7 of which were not enlarged on CT, and 8 bone metastases. In the 20 patients studied with both techniques, a total of 64 and 46 true positive lesions were detected by 18F-FDG-PET/CT and 111In-Octreotide SPECT, respectively. In particular, 18F-FDG uptake was found in 43 lymph nodes and in 7 bone metastases whereas 111In-Octreotide uptake was detected in 27 lymph nodes and in 10 bone metastases.

Conclusions

In MMTC patients, 18F-FDG-PET/CT provides a useful contribution mainly in evaluating lymph node involvement whereas 111In-Octreotide SPECT can contribute to the detection and somatostatin receptor characterization especially of bone lesions.
  相似文献   
996.
PURPOSE: Presently abdominoperineal resection still remains the most diffuse modality of treatment of low rectal cancer. However, a new surgical approach is now available to avoid such a demolitive surgery and a definitive colostomy. METHODS: From March 1990 to March 1993, 58 total rectal resections were performed in 55 patients affected with primary or recurring cancers of the low rectum. As a restorative procedure, a colic J-shaped pouch and a handsewn pouch-endoanal anastomosis was adopted. All of the primary lesions were within 7 cm of the anal verge; in 74 percent the distal tumor margin was located less than 6 cm from the cutaneous edge. RESULTS: Histologic clearance of the rectum cut edge was documented in all cases. Seven patients relapsed locally from 7 to 14 months after surgery and in 3 more cases distant metastases were documented. Postoperative morbidity is low. After colostomy closure in 78 percent of patients, perfect continence was achieved and in 74 percent less than two bowel movements a day were recorded. Fifty patients are presently alive, 46 without evidence of disease. The follow-up ranged from 2 to 37 (median, 13) months. CONCLUSION: This experience, along with data obtained from last year's literature, indicates that a conservative surgical procedure, such as total rectal resection and coloendoanal anastomosis, can be considered a feasible and radical option for treatment of low rectal cancer.  相似文献   
997.
INAMA, G., et al.: Far-Field R Wave Oversensing in Dual Chamber Pacemakers Designed for Atrial Arrhythmia Management: Effect of Pacing Site and Lead Tip to Ring Distance. The aim of the study was to determine the incidence and practical implications of far-field R wave oversensing (FFRWO) and its association with pacing site and lead tip to ring spacing (TTRS) in implantable devices designed to diagnose and treat atrial tachyarrhythmias and programmed with a fixed and short postventricular blanking period. The study included 395 patients who were implanted with a DDDRP pacemaker and prospectively followed. At implant and follow-up visits FFRWO was assessed by analyzing lead electrical measures and atrial tachyarrhythmic episodes collected in the device diagnostics. During a median follow-up of 12 months 11 (2.8%) of 395 patients showed a clinically significant FFRWO that induced inappropriate detection or pacemaker malfunctioning. The atrial pacing site of these 11 patients was right atrium appendage (RAA) for 3 patients, representing 1.1% of 254 RAA patients, coronary sinus ostium (CSO) for 7 patients, representing 7.4% of 94 CSO patients (P < 0.005 vs RAA), and lateral wall (LW) for 1 (2.9%) of 34 LW patients. The minimal value of the FFRWO to P wave ratio, measured at implant, associated with a clinically significant FFRWO was 0.6; therefore, a value of 0.5 was used as a cutoff to identify patients at risk of undesirable device behavior induced by FFRWO: there were 11 (9.6%) of 114 of RAA patients with short (< or = 10 mm) TTRS, 22 (18.8%) of 117 of RAA patients with long (> or = 17 mm) TTRS (P < 0.05 vs short TTRS), 21 (30.6%) of 64 of CSO patients short TTRS (P < 0.001 vs RAA patients with short TTRS) and 3 (30%) of 10 of CSO patients with long TTRS. The analysis showed that, despite the short postventricular blanking time, FFRWO inducing undesired functioning in AT500 pacemakers is infrequent (2.8% of patients). Compared to RAA, the CSO lead position was more frequently associated with FFRWO.TTRS < 10 mm was associated with lower risk of clinically significant FFRWO in RAA. (PACE 2004; 27:1221-1230).  相似文献   
998.
A diverse T cell receptor (TCR) repertoire is essential for protection against a variety of pathogens, and TCR repertoire size is believed to decline with age. However, the precise size of human TCR repertoires, in both total and subsets of T cells, as well as their changes with age, are not fully characterized. We conducted a longitudinal analysis of the human blood TCRα and TCRβ repertoire of CD4+ and CD8+ T cell subsets using a unique molecular identifier–based (UMI-based) RNA-seq method. Thorough analysis of 1.9 × 108 T cells yielded the lower estimate of TCR repertoire richness in an adult at 3.8 × 108. Alterations of the TCR repertoire with age were observed in all 4 subsets of T cells. The greatest reduction was observed in naive CD8+ T cells, while the greatest clonal expansion was in memory CD8+ T cells, and the highest increased retention of TCR sequences was in memory CD8+ T cells. Our results demonstrated that age-related TCR repertoire attrition is subset specific and more profound for CD8+ than CD4+ T cells, suggesting that aging has a more profound effect on cytotoxic as opposed to helper T cell functions. This may explain the increased susceptibility of older adults to novel infections.  相似文献   
999.
The objective of this study was to describe the functional profiles of patients with Parkinson's disease (PD), and the relationships between impairment in body functions, limitations in activities, and environmental factors, using the World Health Organization's International Classification of Functioning, Disability, and Health (ICF). Patients were consecutively enrolled, and the ICF checklist was administered. Two count-based indices were developed: 'extension', containing ICF categories rated with qualifiers 1-4 and 'severity', containing ICF categories rated with qualifiers 3-4. Categories rated with qualifiers 1-4 in at least 50% of patients are described separately. Spearman's correlation analysis was carried out to identify the relationships between impairments in body functions (BF) and body structures, activities and participation, and environmental factors (EF); linear regressions were performed to identify the best predictors of performance indices in activities and participation. A total of 96 patients were enrolled; 34 categories rated with qualifiers 1-4 in at least 50% of patients are reported, and most of them describe impairment in movement-related functions and limitations in mobility and self-care. Performance indices are significantly lower than capacity and significant relationships with both BF impairments and EF are observed. High difficulties in activities and participation performance are connected with both presence of severe BF symptoms and relevant barriers in EF. Both BF and EF play a relevant role in improving functioning of the patients with PD. The connection between EF barriers and severe problems in activities and participation performance suggests the need of fostering participation of patients with PD by promoting facilitators among EFs. Methodologies and tools are needed to couple information on symptoms, on the difficulties in executing activities, and on environmental features.  相似文献   
1000.
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