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OBJECTIVE: The purpose of this study was to compare HER-2/neu expression on biopsies obtained from early stage cervical cancer, primary cell lines established therefrom, established cervical cancer cell lines, and metastatic or recurrent sites of disease; and to evaluate the sensitivity of primary cervical cancer cell lines to treatment with a humanized MAb against HER-2/neu (Herceptin). METHODS: Surface HER-2/neu expression on 18 cervical cancer cell lines was compared to HER-2/neu detection by immunohistochemistry on biopsies obtained from the original tumors (10 patients) and sites of recurrence (2 patients). Primary cell lines were tested for sensitivity to Herceptin-mediated antibody-dependent cellular cytotoxicity (ADCC) and sensitivity to Herceptin-mediated inhibition of proliferation. RESULTS: Nine out of 10 primary (90%) and 8 out of 8 (100%) established cervical cancer cell lines expressed HER-2/neu by flow cytometry. Surprisingly, all HER-2/neu-positive primary cell lines were derived from tumor biopsies that scored negative (i.e., 0 to 1+) for HER-2/neu expression by immunohistochemistry. Heavy staining for HER-2/neu (i.e., 3+) was found in the recurrent/metastatic lesions of the two relapsed patients. Importantly, all HER-2/neu-positive primary cell lines were highly sensitive to Herceptin-mediated ADCC, and their proliferation was also significantly inhibited by Herceptin. A significant enhancement of Herceptin-mediated ADCC was demonstrated when effector cells were exposed to low doses of IL-2 in vitro. CONCLUSIONS: Early stage cervical cancer may develop a population of HER-2/neu-positive cells with a selective growth advantage over HER-2/neu-negative cells. Therapy which targets HER-2/neu may be more effective in patients with cervical cancer than indicated by the commonly low expression of HER-2/neu in tumors removed at the time of primary treatment.  相似文献   
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OBJECTIVE: To investigate the prevalence of renal impairment in patients with ovarian cancer at the time of the diagnosis. STUDY DESIGN: Creatinine clearance was estimated according to Cockcroft and Gault (C&G Ccr), glomerular filtration rate (GFR) was determined as renal clearance of 99mTc-DTPA, and renal ultrasound was performed in 60 consecutive patients with newly diagnosed ovarian cancer. RESULTS: A 28% of the total population studied had a GFR <60 ml/min/1.73 m(2). A moderate/severe dilation of the upper urinary tract was found in 12% of patients. The length of kidneys ranged between 9.0 and 13.5 cm, and a statistically significant correlation was found between kidney length and values of GFR. CONCLUSION: A reduction in renal function and a moderate to severe dilation of upper urinary tract frequently occur in patients with ovarian cancer at the time of the diagnosis.  相似文献   
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The accuracy of a new bedside, rapid and quantitative D-Dimer assay (Cardiac D-Dimer) was evaluated in outpatients with clinically suspected deep vein thrombosis (DVT); VIDAS test was used as reference method. Eighty consecutive outpatients with suspected DVT of a lower limb were included in the study. Patients were classified as DVT positive or negative according to results of objective test (serial CUS), pretest clinical probability and 3-month follow-up. DVT was diagnosed in 32/80 patients (40%). The performance of the two D-Dimer assays was comparable, as indicated by the areas under the ROC curves (0.89 and 0.88, for Cardiac D-Dimer and VIDAS, respectively) and the coefficient of correlation (r=0.91). The reproducibility of the test was acceptable (from 6.2% to 12.0%). The sensitivity and negative predictive values were 100% for both tests. The specificity (SP) and positive predictive values (PPV) were similar (SP: 50.0% and 52.0%, PPV: 57.1% and 58.2%, for Cardiac D-Dimer and VIDAS, respectively). The Cardiac D-Dimer test proved to be very accurate and produced results fully comparable to those obtained with the VIDAS test. Since the test can be directly performed in the emergency room within a few minutes, it seems to have great clinical potential. The place of this assay in the diagnostic strategy of DVT remains to be determined in prospective management studies.  相似文献   
67.
This study set out to explore the frequency and correlates of suicidal ideation in a community sample of school-aged adolescents living in a northeastern area of Italy. The study involved a mixed male–female sample of 1000 adolescents, corresponding to 10% of the young population aged 15–19 in the district. We investigated psychological distress through the revised Symptom Checklist (SCL-90-R), from which we also derived our indicators on suicidality (items concerning hopelessness and suicidal ideation). Propensity to aggression was measured with an Italian version of the Aggression Questionnaire. Females scored significantly higher than males on all SCL-90-R subscales, with the exception of the hostility subscale. In our sample, 30.8% of females and 25.3% of males reported having thought about suicide; one adolescent out of 20 reported suicidal ideation of high intensity (5% out of the total sample in both genders). Males scored significantly higher than females on the Aggression Questionnaire. Both males and females who reported suicidal feelings had significantly higher scores on the Aggression Questionnaire than did those who denied suicidal ideation. Suicidal ideation is a rather widespread occurrence among adolescents and correlates with other indicators of psychological distress. Psychological distress in adolescence might also be expressed through turbulent behaviors and conduct disorders. Identification of the mental disorders underlying a higher propensity to aggression might help to prevent other negative outcomes such as suicide.  相似文献   
68.
The Lot1 gene encodes a zinc finger protein that, in vitro, concurrently regulates apoptosis and cell cycle arrest and belongs to a recently identified family of proteins with oncogenic and tumor-supressor functions. The present study, based on the development of the first antibody reportedly produced against rat Lot1, examines protein expression during normal development of the rat cerebellum and following methylazoxymethanol (MAM) administration, which results in hypoplasia of the cerebellar granule cell population. Using light microscopic immunocytochemistry, specific immunostaining for the Lot1 protein was observed at postnatal days 2 to 7 in the superficial external granule layer composed primarily of proliferating neuronal precursor cells. Purkinje cells showed distinct nuclear labeling at P7. In the adult cerebellum, the overall low Lot1 level was essentially associated with Purkinje cells. Experimentally altered developmental conditions, such as those obtained through MAM-induced microencephaly, did not drastically affect the pattern of Lot1 expression. In particular, Purkinje cells continued to show normal levels of immunoreactivity notwithstanding the altered cerebellar architecture. Primary cultures of cerebellar granule cells showed a temporal pattern of Lot1 expression resembling that of in vivo development, with mRNA and protein levels progressively decreasing with differentiation. When cerebellar granule cells were exposed to different neurotoxic challenges, Lot1 appeared not affected by purely apoptotic cell death, while transitorily induced by mixed necrotic-apoptotic cell death.  相似文献   
69.
EEG power spectra changes and forebrain ischemia in rats   总被引:5,自引:0,他引:5  
BACKGROUND: Several animal models of cerebral ischemia have been developed to investigate both pathophysiology and pharmacological treatment. The aim of this study was to verify the prognostic value of EEG power spectra analysis in a two-vessel plus hypotension rat model of transient global ischemia. METHODS: Spontaneously hypertensive rats (SHRs) and Wistar Kyoto rats (WKYs) were subjected to 20 min bilateral common carotid artery occlusion plus hypotension by sodium nitroprusside followed by reperfusion for seven days. Sham-operated animals served as controls. The changes after ischemia in EEG power spectra, and their relations with neuronal damage and astrocytic response were investigated. RESULTS: The EEG analysis revealed that in SHRs and WKYs, ischemia produced a dramatic increase in delta activity and a decrease in theta, beta and alpha activities derived from both cortical and hippocampal areas. EEG activity reverted to normal values more quickly in WKYs than in SHRs which did not recover cortical and hippocampal alpha and beta activities even at six days of reperfusion. SHRs presented more severe damage and intense astrocytosis than WKYs in almost all the brain regions analyzed. In SHRs, hippocampal delta activity was positively correlated with the degree of neuronal necrosis and astrocytic activation, whereas theta, alpha and beta activities correlated negatively. No correlations were found in WKYs. CONCLUSIONS: These data indicate that the hippocampal bioelectrical activity recorded in SHRs from the beginning of reperfusion could be useful for predicting the ischemic outcome and evaluating the effects of pharmacological interventions.  相似文献   
70.
Dopamine neurons of the substantia nigra pars compacta receive a prominent serotonin (5-HT) projection from the dorsal raphe nucleus and important functional interactions between the serotonergic and the dopaminergic system have been postulated. In the present report we examined the role of 5-HT in the modulation of the metabotropic glutamate receptor-mediated inhibitory postsynaptic current (mGluR-IPSC) in midbrain dopamine neurons, and we found a reversible depression of this synaptic response at concentrations of 5-HT ranging from 100 nm to 30 microm (EC50 1.06 microm). This resulted in a shift towards excitation of the overall dopamine neuron response to glutamatergic synaptic input. This effect was not because of a direct modulation of the Ca2+-sensitive K+ conductances underlying the mGluR-IPSC, but was associated with a decrease in the intracellular calcium signal triggered by mGluR stimulation. Similar results were obtained with alpha-methyl-5-hydroxytryptamine and 5-methoxytryptamine, but not with 5-carboxamidotryptamine or 1-(3-chlorophenyl) piperazine. No significant depression of the mGluR-IPSC by 5-HT was observed in the presence of the 5-HT2 antagonist cinanserin or the 5-HT4 receptor antagonist RS 23597-190, whereas the 5-HT2C antagonist RS 102221 was ineffective. Our results demonstrate a powerful inhibition of the mGluR-IPSC by 5-HT in midbrain dopamine neurons, most probably through stimulation of 5-HT2A and 5-HT4 receptors.  相似文献   
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