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71.
Wet dog shakes (WDS) and head shakes (HS) are associated with experimentally induced convulsive seizures. We sought to determine whether these behaviors are correlated or not with major (status epilepticus (SE) or fully kindled animals) or minor (non-SE or partially kindled animals) seizure severity. WDS are directly correlated with SE induced by intracerebral star fruit extract (Averrhoa carambola) injection and with kindled animals in the amygdala fast kindling model. On the other hand, WDS are inversely correlated with SE induced by intracerebral bicuculline and pilocarpine injections. Systemic pilocarpine in animals pretreated with methyl-scopolamine barely induced WDS or HS. The role of shaking behaviors may vary from ictal to anticonvulsant depending on the experimental seizure model, circuitries involved, and stimulus intensity. The physical presence of acrylic helmets may per se inhibit the HS response. Also, methyl-scopolamine, a drug incapable of crossing the blood-brain barrier, can induce HS in animals without acrylic helmets.  相似文献   
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73.
Zinc is present in high concentration in many structures of the limbic circuitry, however the role of zinc as a neuromodulator in such synapses is still uncertain. In this work, we verified the effects of zinc chelation in an animal model of epileptogenesis induced by amygdala rapid kindling.

The basolateral amygdala was electrically stimulated ten times per day for 2 days. A single stimulus was applied on the third day. Stimulated animals received injections of PBS or the zinc chelator diethildythiocarbamate acid (DEDTC) before each stimulus series. Animals were monitored with video-EEG and were perfused 3 h after the last stimulus for subsequent neo-Timm and Fluoro-Jade B analysis.

Zinc chelation decreased the duration of both behavioral seizures and electrical after-discharges, and also decreased the EEG spikes frequency, without changing the progression of behavioral seizure severity. These results indicate that the zinc ion may have a facilitatory role during kindling progression.  相似文献   

74.
Tumor-released microvesicles as vehicles of immunosuppression   总被引:10,自引:0,他引:10  
Tumor-released microvesicles, or exosomes, which are abundant in the body fluids of patients with cancer, are likely to be involved in tumor progression. We recently showed that microvesicles released by human melanoma and colorectal carcinoma cells can promote the differentiation of monocytes to myeloid-derived suppressor cells which support tumoral growth and immune escape. These findings underscore an important role for these extracellular organelles in remodeling tumor-stromal interactions to promote malignancy.  相似文献   
75.
BRAFV600E is the most represented somatic point mutation in cutaneous melanoma, thus providing a unique molecular marker for this disease. The development of efficient methods for its detection in free circulating DNA of patients may lead to the improvement of diagnostic and prognostic tools. With this aim, we evaluated whether BRAFV600E represents a detectable marker in the plasma/serum from melanoma patients in a pilot study. Circulating cell-free DNA was extracted from the serum or plasma of 15 healthy donors and 41 melanoma patients at different clinical stages and obtained either presurgery or after surgery during follow-up. Quantitative analysis showed higher levels of circulating free DNA in patients compared to controls, with the highest levels detected in samples obtained presurgery and at stage IV. Four different PCR methods were compared for their capacity to amplify a few copies of BRAFV600E in wild-type DNA. BRAFV600E was detectable in circulating DNA of 12 patients and in none of the controls; only 1 PCR method reproducibly amplified BRAFV600E. Positive samples were obtained from 8/13 patients at stage IV and from 4/24 patients at stage III, but not in 4 patients at stage I-II; half of the positives were obtained presurgery and half at follow-up. Correspondence between circulating DNA and related tumors were examined for 20 patients, and a correlation was found for stage IV patients. In conclusion, this method can be utilized for monitoring the disease in stage IV melanoma patients but it appears unsatisfactory for the early detection of melanoma.  相似文献   
76.
Background and aimsVariations in mixed platelet–leukocyte conjugate formation in human whole blood could be genetically determined. We quantified platelet and leukocyte activation and interaction in families with or without early myocardial infarction and evaluated their heritability, genetic correlation and linkage to the 9p21.3 region.Methods and resultsThe study population included 739 subjects (≥15 years old) from 54 large pedigrees, 23 with and 31 without familial myocardial infarction. Mixed platelet–leukocyte conjugates and markers of platelet or leukocyte activation (P-selectin, CD11b and L-selectin surface expression) were measured both before and after in vitro blood stimulation with collagen-ADP.All traits had significant genetic components (17.5–65.3% of the phenotypic variability), while shared household effects (0–39.6%) and environmental covariates (0–10.2%) tended to be smaller. Stimulated platelet-polymorphonuclear leukocyte (PMN) and platelet–monocyte conjugates showed the highest linkage to the 9p21.3 region (LOD = 0.94 and 1.33, respectively; empirical p value = 0.017 and 0.009). PMN markers resulted strongly genetically correlated between them in bivariate analysis among pairs of quantitative traits.ConclusionThis study supports a genetic regulation of human mixed platelet–leukocyte conjugates.  相似文献   
77.
A reduction in mean erythrocyte volume has been reported in some strains of genetically hypertensive rat, and more recently it has been suggested that a similar alteration might be found in human essential hypertension. The relationship between erythrocyte volume and blood pressure was therefore studied in a random sample of an untreated male working population (n = 317; age 45.1 +/- 6.4 years, mean +/- s.d.). Neither systolic nor diastolic blood pressures were found to be related to erythrocyte volume (r = 0.022 and r = -0.014, respectively); in fact, erythrocyte volume was not different across quintiles of blood pressure. Smokers (n = 171) had lower blood pressure and a greater erythrocyte volume than non-smokers or ex-smokers (n = 144; 91.6 +/- 4.7 versus 88.2 +/- 5.5 fl; P less than 0.001), and heavy drinkers (greater than 110 g ethanol/day) had higher blood pressure and a greater erythrocyte volume compared with the rest of the study population (P less than 0.01). However, after adjustment of erythrocyte volume for these two potentially confounding factors, again no statistical association was found with blood pressure. The present study, therefore, does not support the hypothesis of a negative association between erythrocyte volume and blood pressure, whereas it confirms that the smoking habit and habitual alcohol intake are strong determinants of erythrocyte volume.  相似文献   
78.
PURPOSE: Heat shock proteins (HSP) from tumor cells contain the gp96 polypeptide associated with cancer-specific antigenic peptides. Mice that are immunized with HSP/peptide-complex (HSPPC) derived from cancer tissue reject tumor from which HSPs are purified. We tested in humans whether vaccination with HSPPC-gp96 (Oncophage) from autologous liver metastases of colorectal carcinoma induces cancer-specific T-cell responses in patients rendered disease free by surgery. Experimental Design: Twenty-nine consecutive patients underwent radical resection of liver metastases [Memorial Sloan-Kettering Cancer Center (MSKCC) score 1-3 (good prognosis), 18 patients; score 4-5 (bad prognosis), 11 patients] and received autologous tumor-derived HSPPC-96. Two vaccine cycles were administered (four weekly injections followed by four biweekly injections after 8 weeks). Class-I HLA-restricted, anti-colon cancer lines T-cell response was measured by ELISPOT assay on peripheral blood mononuclear cells (PBMCs) obtained before and after vaccination. Feasibility, safety, and possible clinical benefits were also evaluated. RESULTS: Either a de novo induced or a significant increase of preexisting class I HLA-restricted T-cell-mediated anti-colon cancer response was observed in 15 (52%) of 29 patients. Frequency of CD3+, CD45RA+, and CCR7- T lymphocytes increased in immune responders. No relevant toxicity was observed. As expected, patients with good prognosis had a significantly better clinical outcome than those with poor prognosis [2-year overall survival (OS), 89 versus 64%, P = 0.001; disease-free survival (DFS), 46 versus 18%, P = 0.001]. Patients with immune response had a statistically significant clinical advantage over nonresponding subjects (2-year OS, 100% versus 50%, P = 0.001; DFS, 51% versus 8%, P = 0.0001). Occurrence of immune response led to better tumor-free survival, whatever the predicted prognosis was (hazard ratio, 0.11-0.12 with/without stratification; P = 0.0012-0.0003). CONCLUSIONS: HSPPC-96 vaccination after resection of colorectal liver metastases is safe and elicits a significant increase in CD8+ T-cell response against colon cancer. In this limited number of patients, two-year OS and DFS were significantly improved in subjects with postvaccination antitumor immune response, independently from other clinical prognostic factors.  相似文献   
79.
Prototheca species are ubiquitous, aerobic, unicellular algae closely related to the green algae Chlorella. Their involvement in human disease--in both immunocompetent and immunocompromised patients--has been reported with increasing frequency. The wide array of presentations has included cutaneous, subcutaneous, mucosal, bursal, catheter-related, and (in rare instances) systemic disease. We report a case of protothecosis complicating prolonged endotracheal intubation presenting as a nasopharyngeal ulceration with a soft-tissue mass, and we review the presentation, treatment, and outcome of the 59 previously reported cases of protothecosis. Optimal therapy for protothecosis includes excision (where possible) followed by systemic administration of amphotericin B; the sole exception is in the case of olecranon bursitis, where excision alone appears curative. The role of the newer imidazoles is yet to be determined.  相似文献   
80.
The characteristics of urinary o-cresol (o-C) and urinary toluene (TOL-U) as biomarkers of occupational exposure to toluene were comparatively evaluated. One hundred healthy male rotogravure printing workers and 161 male and female control subjects were studied. Personal exposure to airborne toluene (TOL-A) during the shift was determined as a time-weighted average. Simple analytical procedures based on solid phase microextraction followed by gas chromatography/mass spectometry analysis were applied to the determination of end-shift o-C and TOL-U. Median TOL-A was 48 (6.0-162.0) mg/m3 in printers and 0.021 (<0.003-0.137) mg/m3 in controls. o-C was 0.185 (0.032-0.948) mg/g creatinine in printers and 0.027 (<0.006-0.330) mg/g creatinine in the controls. TOL-U was 7.6 (1.8-23.9) microg/L in printers and 0.140 (0.094-0.593) microg/L in the controls. According to all indices, exposure to toluene was higher in printers than in the controls. Nevertheless, the distribution of o-C in the two groups partially overlapped, whereas such behavior was not found in TOL-U. Both o-C and TOL-U in printers were correlated with TOL-A (Pearson's on log10-transformed variables r = 0.704 and 0.844, respectively) and with each other (r = 0.683). Smoking habits significantly increased the excretion of o-C but not of TOL-U. From the point of view of sampling conditions and analytical requirements, TOL-U and o-C showed similar properties, but comparison of their intrinsic characteristics showed that TOL-U had higher specificity and sensitivity, lower background values, was better correlated with airborne exposure, and was not influenced by cigarette smoking. Therefore TOL-U may be considered superior to o-C as a biomarker of occupational exposure to toluene.  相似文献   
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