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101.
Relationship of epileptic seizures to sleep stage and sleep depth   总被引:10,自引:0,他引:10  
Minecan D  Natarajan A  Marzec M  Malow B 《Sleep》2002,25(8):899-904
STUDY OBJECTIVES: Interictal epileptiform discharges (IEDs) are facilitated by NREM stages 3 and 4 sleep and as sleep is deepening. To determine whether sleep influences seizures in a similar way to IEDs, we examined seizure rates in various stages of sleep in epilepsy patients undergoing overnight video-EEG-polysomnography (VPSG). DESIGN: Cross-sectional study. SETTING: Neurology Department. PATIENTS, MEASUREMENTS, AND INTERVENTIONS: We reviewed VPSGs from our Sleep and Epilepsy Laboratories to identify patients with recorded seizures during sleep. A total of 55 patients having 117 seizures were identified. RESULTS: Ninety-five percent of seizures occurred in NREM sleep (61% in stage 2, 20% in stage 1, 14% in stages 3 and 4 combined), and 5% in REM sleep. Adjusting for time spent in each stage of sleep, patients had 0.34 seizures per hour in stage 1, 0.38 seizures per hour in stage 2, 0.29 seizures/hr in stage 3 and 4 combined, and 0.09 seizures per hour in REM sleep. Seizures/hour was higher in NREM sleep (0.35 for NREM and 0.09 for REM; p=0.0001). For single seizures occurring in 1 night, seizure rate was significantly higher in NREM stages 1 and 2 as compared to NREM stages 3 and 4 sleep. A significant increase in log delta power, an automated measure of sleep depth, was observed in the 10 minutes prior to seizures. CONCLUSIONS: Both seizures and IEDs are facilitated by NREM sleep. While deeper stages of NREM sleep activate IEDs, lighter stages of NREM sleep promote seizures, at least for single seizures occurring in 1 night.  相似文献   
102.
We report a new case of mesothelioma that presented with an isolated lingual metastasis 14 months after initial diagnosis. The patient was a 71-year-old man with a history of pleural decortication and chemotherapy for epithelioid mesothelioma who recently complained of chronic bleeding from a nodular consolidation of tongue. There was no clinical or instrumental evidence of extrathoracic tumor spread. Microscopic examination of a lingual biopsy specimen revealed nests of atypical polygonal cells with moderate cytoplasm, immunopositive for keratins, epithelial membrane antigen, vimentin, thrombomodulin, and calretinin. This case provides additional evidence that mesothelioma could rarely, but not exceptionally, metastatize, to unusual sites such as the tongue. In that location it can mimic primary poorly differentiated squamous carcinoma or adenocarcinoma as well as a number of other metastatic malignancies. In addition to obvious medicolegal implication, metastatic mesothelioma should be correctly recognized so as to avoid useless radical treatment.  相似文献   
103.
Although the haemagglutination inhibition assay is considered the "gold standard" for antigenic characterisation of influenza viruses, some limitations of this technique are well known. A new microneutralisation assay, as a tool for antigenic characterisation of influenza B viruses, has been standardised and its performance evaluated in comparison with the haemagglutination inhibition test in the light of molecular characterisation of the haemagglutinin. Twelve B viruses belonging to the two lineages and the four sub-lineages discriminated by phylogenetic analysis of HA were tested. The microneutralisation assay clearly distinguishes viruses belonging to different lineages and, in addition, discriminates strains belonging to different sub-lineages that are poorly or not discriminated using the haemagglutination inhibition test. This new microneutralisation assay could provide a useful tool for antigenic characterisation of circulating influenza viruses and contribute, together with the haemagglutination inhibition test and sequence analysis of the haemagglutinin and neuraminidase, in the choice of the strain for use in vaccine composition.  相似文献   
104.
The surface expression of given HLA class I alleles protects target cells from lysis mediated by natural killer (NK) clones specific for these (or related) alleles. We could define two groups of NK clones specifically recognizing either Cw4 and related C alleles (“group 1”) or Cw3 and related C alleles (“group 2”), respectively. Monoclonal antibodies (mAb) to class I molecules should interfere with the interaction between NK receptors and class I molecules, thus resulting in lysis of protected target cells. However, none of the numerous available mAb to class I molecules had this effect. Therefore, we attempted to select new mAb on the basis of their ability to induce lysis of Cw4- or Cw3-protected lymphoblastoid cell lines by “group 1” or “group 2” NK clones, respectively. From mice immunized with phytohemagglutinin (PHA)-activated lymphocytes expressing either Cw3 or Cw4 alleles, two mAb were selected, the 6A4 (IgG1) and the A6-136 (IgM), on the basis of their ability to induce lysis of protected target cell. Both mAb immunoprecipitated molecules which, in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, gave two bands of 45 and 12 kDa, typical of the class I heavy chain and β2 microglobulin, respectively. It has been proposed (but not proven), that self major histocompatibility complex class I molecules protect normal cells from autologous NK cell lysis. Thus, we used the 6A4 and A6-136 mAb to assess this possibility directly. Cw4-specific (“group 1”) and Cw3-specific (“group 2”) NK clones were isolated from donors expressing the corresponding (or related) protective C alleles. None of these clones lysed autologous PHA-induced blasts, used as target cells. However, addition of the F(ab′)2 of 6A4 mAb or the A6-136 mAb resulted in lysis of autologous target cells by “group 1” or “group 2” NK clones, respectively. These data provide direct evidence that the expression of class I molecules protects normal cells from lysis by autologous NK cells.  相似文献   
105.
We have evaluated the effects of a treatment with soluble interleukin-1 receptor (sIL-1R) in the accelerated model of autoimmune diabetes induced by cyclophosphamide (CY) in the non-obese diabetic (NOD) mouse. Prior to the CY challenge (350 mg/kg body weight), female euglycemic NOD mice were randomly divided into three groups (A–C). Groups B and C were treated daily from 1 day before to 13 days after the CY challenge with sIL-1R at doses of 0.2 and 2 mg/kg body weight. Group A was treated with PBS. By 2 weeks after CY administration, an acute form of autoimmune diabetes with glycosuria, hyperglycemia and severe insulitis occurred in the majority (13/20, 65%) of the control mice (group A). In contrast, repeated injections with sIL-1R protected NOD mice from insulin-dependent diabetes mellitus (IDDM) development in a dose-dependent fashion; the incidence of IDDM was 53.3% (8/15) in the mice treated with 0.2 mg/kg and only 6.7% (1/15) in those treated with 2 mg/kg. However, none of the doses of the sIL-1R reduced the extent of insulitis in NOD mice. Importantly, the anti-diabetogenic property of sIL-1R may not involve major T cell function impairment; accordingly, in parallel experiments, splenic lymphoid cells from NOD mice not challenged with CY, but treated with 2 mg/kg sIL-1R for 5 consecutive days showed a normal distribution of mononuclear cell subsets and maintained their capacity to secrete interferon-γ and IL-2 and to proliferate in response to polyclonal mitogenic stimulation with concanavalin A.  相似文献   
106.
E-selectin, an adhesion molecule of the selectin family, is involved in leukocyte adhesion to the endothelium and in the cellular immunological reactions. Expression of this molecule, in fact, is physiologically absent, but it becomes evident on sinusoidal lining cells during inflammatory liver disease. The aim of this study was to evaluate the behavior of E-selectin in chronic hepatitis C (CH-C) patients with persistently normal transaminase in comparison to patients with CH-C and elevated transaminase, and its changes during alpha-interferon therapy. Immunohistochemical localization of E-selectin was also performed on liver tissue specimens of both groups. Fifty-eight subjects were divided into 3 groups: group A included 18 patients with CH-C and persistently normal transaminase; group B 20 patients with CH-C and persistently elevated transaminase levels and group C included 20 healthy subjects, representing the control group. The first two groups were treated with r-IFN at a dose of 6 MU 3 times a week for 3 months and followed-up with 3 MU 3 times a week for another 3 months. Serum baseline values of E-selectin in groups A and B were significantly higher than those in group C (P < 0.04), but there was no difference between groups A and B. Furthermore, there was a trend toward higher E-selectin values as histological severity increased (r = 0.69; P < 0.0001). Post-treatment E-selectin serum values showed a moderate decrease in both groups, but only among responder patients; while E-selectin levels were unchanged in non responders. Immunohistochemical localization showed no staining for E-selectin in normal liver specimens, while there was a quite similar staining for E-selectin in the two groups of patients. In conclusion, this study shows that serum E-selectin levels in patients with CH-C and persistently normal transaminase are higher than in controls and they are associated with severity of liver disease. Liver of these patients express E-selectin molecules, suggesting an activation of the immune system almost identical to that of patients with CH-C and elevated transaminase. In both groups only responder patients showed a moderate decrease below baseline serum values.  相似文献   
107.
The prognostic value of the extent of neovascularization in cutaneous melanoma is a highly controversial issue. The aim of the current study was to evaluate whether the morphometric analysis of tumor vascularity may be helpful in predicting the clinical outcome of patients with thick cutaneous melanomas. A series of 15 patients with melanoma (>3 mm in thickness) who did not experience disease progression after long-term follow-up (10 years) and 30 matched controls who underwent recurrence and/or metastases were selected for the study. Microvessels were immunohistochemically stained with anti-CD31 antibody. Several parameters, including vessel number, vascular density, vessel area, equivalent circle diameter, perimeter, shape factor, compactness, and the number of vascular ramifications per 100 vessel sections, were quantitatively assessed by a computer-aided semi-automatic image analysis system. Mean vessel area was 341.69 microm2 in cases without progression and 512.55 microm2 in the progressed melanomas (P=0.008, Mann-Whitney U test). The mean equivalent circle diameter was 18.95 microm in non-progressed melanomas and 22.57 microm in progressed melanomas (P=0.009). The mean number of ramifications was 0.8 in cases without progression and 1.9 in the controls (P=0.03). Microvessel count and vascular density were higher in progressed cases (17.37 vs. 11.73 and 28.94/mm2 vs. 19.55/mm2, respectively), but the difference did not reach statistical significance (P=0.06). Our results suggest that neovascularization is a critical event in the progression of thick melanoma. Its prognostic significance is better assessed by quantification of vessel area, equivalent circle diameter, and microvessel branching, whereas microvessel count and vascular density do not provide significant prognostic information.  相似文献   
108.
Fatal Familial Insomnia is a hereditary prion disease characterized by a mutation at codon 178 of the prion protein gene cosegregating with the methionine polymorphism at codon 129 of the mutated allele. It is characterized by disturbances of the wake-sleep cycle, dysautonomia and somatomotor manifestations (myoclonus, ataxia, dysarthria, spasticity). PET studies disclose severe thalamic and additionally cortical hypometabolism. Neuropathology shows marked neuronal loss and gliosis in the thalamus, especially the medio-dorsal and anterior-ventral nuclei, olivary hypertrophy and some spongiosis of the cerebral cortex. Detailed analysis of 14 cases from 5 unrelated families showed that patients ran either a short (9.1+ 1.1 months) or a prolonged (30.8 + 21.3 months) clinical course according to whether they were homozygote met/met or heterozygote met/val at codon 129. Moreover, homozygotes had more prominent oneiric episodes, insomnia and dysautonomia at onset, whereas heterozygotes showed ataxia and dysarthria at onset, earlier sphincter loss and epileptic Grand Mai seizures; they also displayed more extensive cortical involvement on PET and at postmortem examination. Our data suggest that the phenotype expression of Fatal Familial Insomnia is related, at least partly, to the polymorphism at codon 129 of the prion protein-gene.  相似文献   
109.
110.
Evidence for an inherited component in the determination of the preferred eye in sighting dominance is presented that replicates the earlier findings by Merrell (1957). Significantly more left-sighting-preferent individuals were found in the progeny of R×L and L×L matings than in the R×R matings.The preparation of this study was supported by National Institute of Mental Health Grant MH-21989.  相似文献   
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