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101.
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WJ Mazzocco 《Canadian Metallurgical Quarterly》1998,101(10):17-19
104.
WJ Hoogendijk JS Purba MA Hofman RA de Vos EN Jansen DF Swaab 《Canadian Metallurgical Quarterly》1998,43(12):913-917
BACKGROUND: Depression is frequently encountered in Parkinson's disease (PD). In addition, more than half of the PD patients have a disturbed dexamethasone suppression test, which is associated with increased activity of corticotropin-releasing hormone (CRH) neurons. We recently found an increase in CRH neuron number, CRH-messenger RNA, and vasopressin colocalization in CRH neurons in the paraventricular nucleus (PVN) of depressed patients, which may be involved in the pathogenesis of depression. METHODS: The number of neurons expressing CRH was determined in the PVN of 6 depressed PD patients with a high score (> or = 13) on the Hamilton Depression Rating Scale, 6 nondepressed PD patients, and 6 controls. RESULTS: The three groups did not differ in the number of neurons expressing CRH. CONCLUSIONS: We hypothesize that activation of CRH neurons in the PVN, as we recently observed in idiopathic depression, does not play an essential role in depression in PD. 相似文献
105.
J van Ark-Otte MA Kedde WJ van der Vijgh AM Dingemans WJ Jansen HM Pinedo E Boven G Giaccone 《Canadian Metallurgical Quarterly》1998,77(12):2171-2176
Irinotecan (CPT-11) is a semisynthetic camptothecin derivative with a broad spectrum of anti-tumour activity. Carboxylesterase (CE) catalyses the conversion of CPT-11 to SN-38 (7-ethyl-10-hydroxycamptothecin), the active form of CPT-11. The antiproliferative effects of CPT-11 and SN-38, CE-activity and topoisomerase I protein expression were investigated in five human small-cell lung cancer (SCLC) cell lines and four human non-small-cell lung cancer (NSCLC) cell lines. Antiproliferative activity, expressed as IC50 values, was determined using the MTT assay. CPT-11 was significantly more active in SCLC than in NSCLC cell lines (P = 0.0036), whereas no significant difference between histological types was observed with SN-38. A significant correlation (r2 = 0.52, P = 0.028) was observed between CE activity and chemosensitivity to CPT-11 but not to SN-38, and significantly higher CE activity was observed in SCLC compared with NSCLC cell lines (P = 0.025). Western blotting experiments showed topoisomerase I protein expressions within a factor of 2, and a granular nuclear staining was detectable in all cell lines by immunocytochemistry of cytospins. No correlation was observed between protein expression and sensitivity to CPT-11 or SN-38. Cellular and medium concentrations of CPT-11 and SN-38 were measured by high-performance liquid chromatography (HPLC) in one SCLC cell line with high CE activity and high sensitivity to CPT-11, and one NSCLC cell line with low sensitivity to CPT-11 and CE activity. Intracellular concentrations of CPT-11 and SN-38 were higher in the SCLC cell line, and this was associated with an increase in cellular uptake of CPT-11 compared with the medium, and an increased intracellular formation of SN-38. In conclusion, CE activity appears to be associated with higher sensitivity to CPT-11 in human lung cancer cell lines and may partly explain the difference in the in vitro sensitivity to CPT-11 between SCLC and NSCLC cells. The assessment of CE activity in clinical material of lung cancer patients undergoing treatment with CPT-11 may be warranted. However, other mechanisms may influence sensitivity to CPT-11, possibly including drug transport. 相似文献
106.
Expression of the neural cell adhesion molecule, NCAM, in frozen sections has been associated with decreased postoperative survival in non-small cell lung carcinoma. Of the various isoforms of NCAM described, the highly sialylated isoform plays a role in the migration of embryonal cells from the neural crest and is expressed by highly malignant tumours such as small cell lung carcinomas. We investigated the clinical significance of expression of this NCAM isoform as a prognostic factor in a series of 96 non-small cell lung carcinomas resected with curative intent. We also evaluated the effect of microwave pre-treatment of formalin-fixed, paraffin-embedded sections on the NCAM immunostaining and related the outcome to the postoperative clinical course of disease. In addition, in an attempt to extend our search for possible molecular markers of unfavourable prognosis in lung cancer, we evaluated increased immunostaining for p53 and cyclin D1 in the same series. We did not find a significant relation between expression of NCAM or its highly sialylated isoform and the length of postoperative survival. The numbers of positive cases (9 and 14, respectively) were relatively low. Increased p53 and cyclin D1 immunostaining (50 and 55 of the 96 tumours) failed to show a significant relation with postoperative survival. In our material, tumour stage was the only significant prognostic factor. 相似文献
107.
JM Bae MY Ahn CH Harn WJ Jeong M Jung YP Lim JR Liu 《Canadian Metallurgical Quarterly》1998,8(4):466-470
STUDY OBJECTIVE: To determine whether an intensive educational campaign of emergency department personnel on the organ donor and procurement process would result in both increased organ donor referrals and organs procured. METHODS: A retrospective review of the performance of an urban teaching ED in identifying and referring potential organ donor candidates was performed. Subsequently an intensive educational campaign of all ED staff, in conjunction with the Regional Organ Procurement Agency of Southern California (ROPA), was initiated. Physicians and nurses were educated about the procurement process, and a ROPA representative was on call 24 hours a day to assist in this process. The need for aggressive resuscitation and vital sign maintenance in potential donors as a strategy to promote organ recovery was emphasized. Reeducation by ROPA occurred every 2 to 3 months. The identification and referral rates were then retrospectively reviewed to evaluate any improvement. RESULTS: In 1994 the initial referral rate of potential organ donors from the ED was 30% (3 of 10) resulting in no organs procured. After the intervention the referral rate increased to 100% (25 of 25) in 1995 (P < .0001). The number of actual donors procured was 0 in 1994, 5 in 1995, and 9 in 1996. The increased ED referrals resulted in 14 and 32 organs procured in 1995 and 1996, respectively. CONCLUSION: Emergency physicians are in a unique position as first caregivers to interact with both potential donors and their families. With intensive education of ED staff, proper identification and referral, as well as timely intervention by organ procurement representatives, the consent and donation rate of organs for transplantation can be increased and maintained. 相似文献
108.
GW Mathern JK Pretorius HI Kornblum D Mendoza A Lozada JP Leite L Chimelli DE Born I Fried AC Sakamoto JA Assirati WJ Peacock GA Ojemann PD Adelson 《Canadian Metallurgical Quarterly》1998,5(3):151-176
This study determined whether hippocampal kainate (KA) receptor mRNA levels were increased or decreased in temporal lobe epilepsy patients compared with nonseizure autopsies. Hippocampal sclerosis (HS; n = 17), nonsclerosis (non-HS; n = 11), and autopsy hippocampi (n = 9) were studied for KA1-2 and GluR5-7 mRNA levels using semiquantitative in situ hybridization techniques, along with neuron densities. Compared with autopsy hippocampi, HS and non-HS cases showed decreased GluR5 and GluR6 hybridization densities per CA2 and/or CA3 pyramid. Furthermore, HS patients demonstrated increased KA2 and GluR5 hybridization densities per granule cell compared with autopsy hippocampi. These findings indicate that chronic temporal lobe seizures were associated with differential changes in hippocampal KA1-2 and GluR5-7 hybridization densities that vary by subfield and pathology group. In temporal lobe epilepsy patients, these results support the hypothesis that pyramidal cell GluR5 and GluR6 mRNA levels are decreased as a consequence of seizures, and in HS patients granule cell KA2 and GluR5 mRNA levels are increased in association with aberrant fascia dentata mossy fiber sprouting and/or hippocampal neuronal loss. 相似文献
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I Hwang AG Balingit WJ Georgitis JC Sisson B Shapiro 《Canadian Metallurgical Quarterly》1998,39(8):1460-1463
Adrenal scintigraphy with 131I-labeled 6-beta-iodomethyl-19-norcholesterol (NP-59) is a technically demanding and complex procedure. However, it can provide crucial and unique information about the functional status of the adrenal glands and guide the appropriate therapeutic management of patients with biochemically proven disease. Since the introduction of this new investigational drug, scintigraphic imaging has been performed using conventional planar techniques. We present an interesting case of primary aldosteronism in which planar scintigraphy and SPECT were combined in an attempt to increase the sensitivity of the study. SPECT revealed scintigraphic evidence of bilateral adrenocortical hyperplasia. Interestingly, the CT scan of this patient showed only an equivocal abnormality in the left adrenal gland, suggestive of an adenoma. 相似文献