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81.
Metastatic renal cell carcinoma has occasionally been reported to mimic malignant pleural mesothelioma. Morphologically, histochemically and immunohistochemically, similarities in the two tumours exist making their differentiation difficult, particularly in biopsy specimens. The aim of this study was to make a comparative immunohistochemical analysis of the two tumours by use of a panel of four antibodies (Leu M1; Ber EP4; thrombomodulin and Tamm-Horsfall protein). Their suitability in differentiating between the two tumours was assessed. We examined 20 cases of renal cell carcinoma and 20 cases of malignant pleural mesothelioma. On immunostaining with Leu M1, 14 of 20 renal cell carcinomas were positive, yielding 70% sensitivity and 95% specificity and one of 20 mesotheliomas. In comparison, Ber EP4 antibody stained only seven of 20 of the renal cell carcinomas. In addition, it was noted that four tubulopapillary pattern renal cell carcinomas stained positively with both anti-Leu M1 antibody and Ber EP4 antibody. Thrombomodulin immunostaining was present in 11 of 20 mesotheliomas (55% sensitivity and demonstrated 95% specificity) and one of 20 renal cell carcinomas. For epithelial mesotheliomas only, thromobomodulin staining was identified in 10 of 14 cases. In the differentiation of renal cell carcinoma from epithelial mesothelioma we recommend the use of Leu M1 and thrombomodulin as diagnostically useful markers. None of the antibodies used in this study was effective in distinguishing sarcomatoid renal cell carcinoma from sarcomatous mesothelioma. Tamm-Horsfall protein showed little diagnostic utility in differentiating the two tumours. 相似文献
82.
G. Wu S. F. Fan Z.-H. Lu R. W. Ledeen S. M. Crain 《Journal of neuroscience research》1995,42(4):493-503
Prolongation of the action potential duration of dorsal root ganglion (DRG) neurons by low (nM) concentrations of opioids occurs through activation of excitatory opioid receptors that are positively coupled via Gs regulatory protein to adenylate cyclase. Previous results suggested GM1 ganglioside to have an essential role in regulating this excitatory response, but not the inhibitory (APD-shortening) response to higher (μM) opioid concentrations. Furthermore, it was proposed that synthesis of GM1 is upregulated by prolonged activation of excitatory opioid receptor functions. To explore this possibility we have utilized cultures of hybrid F11 cells to carry out closely correlated electrophysiological and biochemical analyses of the effects of chronic opioid treatment on a homogeneous population of clonal cells which express many functions characteristic of DRG neurons. We show that chronic opioid exposure of F11 cells does, in fact, result in elevated levels of GM1 as well as cyclic adenosine monophosphate (AMP), concomitant with the onset of opioid excitatory supersensitivity as manifested by naloxone-evoked decreases in voltage-dependent membrane K+ currents. Such elevation of GM1 would be expected to enhance the efficacy of excitatory opioid receptor activation of the Gs/adenylate cyclase/cyclic AMP system, thereby providing a positive feedback mechanism that may account for the remarkable supersensitivity of chronic opioid-treated neurons to the excitatory effects of opioid agonists as well as antagonists. These in vitro findings may provide novel insights into the mechanisms underlying naloxone-precipitated withdrawal syndromes and opioid-induced hyperalgesia after chronic opiatf addiction in vivo. © 1995 Wiley-Liss, Inc. 相似文献
83.
Dr. S. Eggstein MD G. Manthey MT T. Hirsch PhD F. Baas MA B. U. V. Specht MD E. H. Farthmann MD 《Digestive diseases and sciences》1996,41(6):1069-1075
Epidermal growth factor receptors (EGFR) andras mutations are known to play a significant role in controlling cell growth and tumor promotion. Both of them transmit mitogenic signals to the nucleus by activation of Raf-1 kinase. In this study, the expression of EGFR and mutant Ras proteins, and, for the first time, the expression, phosphorylation and kinase activity of Raf-1 kinase have been determined in paired samples of colorectal cancer and mucosa. The tumor and mucosa samples did not differ significantly with regard to Raf-1 kinase content and activity. A major difference between tumors and mucosa was found, however, in the phosphorylation of Raf-1. Most of the mucosa samples (13/20), but only 1/20 of the cancer samples, contained hyperphosphorylated Raf-1. EGFR were significantly (p=0.0025) decreased in the tumors. The decreased phosphorylation of Raf-1 in colonic carcinomas could be the result of activation of Raf-1 phosphatases or inactivation of kinases phosphorylating Raf-1. New forms of treatment based on EGFR overexpression do not seem to be suitable for the majority of colonic cancers.This work was supported by the state of Baden-Württemberg (Verbundforschungsprojekt: Aufklärung von Mechanismen der Tumorentstehung und Tumorabwehr). 相似文献
84.
M. Vrethem B. Lindvall S. Kihlstrand E. Bckman T. Brismar P. Fredman K.G. Henriksson 《European journal of neurology》1996,3(2):156-159
We report improvement in muscle strength in a patient with multifocal motor neuropathy (MMN) when given high-dose intravenous immunoglobin (i.v.-Ig) treatment. The patient had asymmetrical limb weakness, atrophy and absent or weak reflexes, but no sensory disturbances. Neurography showed multiple conduction blocks in peripheral motor nerves but no sensory nerve abnormalities. Serum and anti-GM1 antibodies were not found, however, the patient had serum antibodies against the glycolipid LK1, an epitope found both in glycolipid and also in some glycoproteins in peripheral nerve myelin. Muscle strength improved 5 days after i.v.-Ig therapy, and lasted about 10 weeks. Repeated courses of treatment resulted in similar improvement. This is, to our knowledge, the first patient reported with MMN found to have antibodies against the glycolipid LK1. 相似文献
85.
Elizabeth E. Epstein Barbara S. McCrady Linda S. Hirsch 《Alcoholism, clinical and experimental research》1997,21(3):547-556
Current knowledge about alcohol and marital functioning is limited by restrictive sample selection, inattention to the literature on individual-based alcoholic subtypes, and lack of research linking individual differences among alcoholics to marital functioning. The present study was designed to study marital functioning of alcoholics in light of current alcohol typologies. Subjects were part of a larger study on conjoint treatment of alcoholic males and their female partners. Four typologies—including Type 1/2, In-Home/Out-of-home, SteadyIEpisodic, and EarlyILate Onset—were tested for replicability and discriminant validity before linking them to marital functioning. Discriminant validity was found only for the Early (59%)-versus Late (41 %)-Onset typology; thus, further analyses linked only this typology with marital functioning. At baseline, Early-Onset couples reported more marital instability, and the females in these couples were more distressed. During treatment, Early-Onset couples reported higher daily marital satisfaction than Late-Onset couples. Regardless of age of onset, males reported higher marital satisfaction than their spouses during treatment, but their satisfaction did not increase during treatment. Female partners' marital satisfaction increased during treatment. Female partners of Late-Onset males reported particularly low marital satisfaction during treatment. Parsing the sample according to the early-/late-onset typology yielded different predictors of marital satisfaction for males and females within each subtype. For female partners of Early-Onset alcoholics, psychological distress unrelated to her pattner's drinking severity was most associated with her own marital satisfaction, whereas marital adjustment of female partners of Late-Onset alcoholics was most associated with the male's level of perceptual accuracy regarding her needs. This pattern was reversed for the males; marital adjustment of Early-Onset alcoholics was most associated with his partner's perceptual accuracy of his needs, whereas marital functioning of Late-Onset alcoholics was best accounted for by his own psychological distress. 相似文献
86.
87.
硒和/或维生素E预防大鼠内皮细胞损伤的实验研究 总被引:15,自引:1,他引:14
用含硒(Se0.5mg/kg)和/或维生素E(VE0.6g/kg)的高脂饲料喂养成年雄性Wistar大鼠12周。结果:高脂对照组大鼠血浆前列腺素Flα(6-酮-PGF1α)水平下降,而血清脂质过氧化物(LPO)、血浆血栓素(TXB2)及内皮素(ET)水平上升;补Se、VE及Se+VE可明显降低大鼠血清LPO、血浆TXB2、ET及TXB2/6-酮-PGF1α比值。同时,除了明显提高血浆谷胱甘肽过氧化物酶(GSH-Px)活力外,血浆6-酮-PGF1α浓度明显升高。实验提示,Se和/或VE有调节花生四烯酸代谢及保护内皮细胞的作用。 相似文献
88.
Purpose. To determine whether the non-toxic pentameric B subunit of Cholera toxin (CTB) binding to ganglioside GM1 on both the lipid vesicles and epithelial cells may provide a means to target lipid vesicles to mucosal cells expressing surface GM1.
Methods. Sonicated lipid vesicles containing ganglioside GM1 were prepared. Inter-vesicle cross-linking due to pentameric CTB binding to these GM1 vesicles was determined with a sub-micron particle analyzer. Association of CTB to GM1 vesicles was analyzed with continuous sucrose gradient centrifugation. CTB-mediated binding of GM1 vesicles to human mucosal epithelial cells (Caco-2 and HT-29), mucous membranes of mouse trachea, and nasal tissues were detected with fluorescent labeled vesicles.
Results. An increase in lipid particle size due to binding of CTB to lipid vesicles and inter-vesicles cross-linking was detected. At a 30-to-1 mole ratio of membrane-bound GMl-to-CTB, optimum increase in GM1 vesicle aggregation, was detected. Under such conditions, all the added CTB molecules were associated with GM1 vesicles. Time course analysis showed that inter-vesicles cross linking by CTB was detectable within 10 min. and reached a maximum value at 60 min. CTB associated GM1-vesicles bind to mucosal epithelial cells HT-29 and Caco-2 with similar affinity [Kd = 7.8 × 10–4 M lipid (Caco-2) and 7.6 × 10–4 M lipid (HT-29)]. GM1 mediated binding specificity was demonstrated by blocking with anti-GMl antibody and the insignificant degree of CTB-associated GM1 vesicle binding to GM1 deficient C6 cells.
Conclusions. The CTB-mediated GM1 binding to multiple membrane surfaces provides selective localization of GM1 vesicles to GM1 expressing mucosal cells and tissues. The strategy may be useful in localizing drugs and proteins to gut and respiratory tract mucosa. 相似文献
89.
Zusammenfassung
Eine neu aufgetretene Dyspnoesymptomatik und eine symmetrische, apikal betonte retikulonodul?re Zeichnungsvermehrung im R?ntgen-Thorax
bei jungen rauchenden Erwachsenen müssen an das seltene Krankheitsbild der pulmonalen Histiocytosis X denken lassen. Klinischer
Befund, laborchemische- und Lungenfunktionsuntersuchungen zeigen unspezifische Befunde. Neue radiologische Verfahren wie die
hochaufl?sende Computertomographie (HRCT) leisten bei gezielter Indikationsstellung eine entscheidende differentialdiagnostische
Hilfestellung.
Dieser Fall verdeutlicht die M?glichkeit einer Diagnosesicherung durch transbronchiale Biopsien unter Verzicht auf offene
Lungenbiopsien. Eine ambulante Diagnostik war m?glich, das h?here Risiko eines operativen Eingriffes konnte vermieden werden.
Die Indikation zur Therapie ist nicht gesichert und wird daher durch den Grad der subjektiven bzw. funktionellen Einschr?nkung
sowie den Verlauf bestimmt. 相似文献
90.
PACAP is a hypothalamic hypophysiotropic factor that acts upon a number of pituitary cells, including gonadotrophs. In the gonadotroph-derived αT3-1 cell line, PACAP acts via PVR1 receptors to stimulate adenylyl cyclase and phosphoinositidase C. PACAP-stimulated cAMP accumulation is inhibited by protein kinase C-activating phorbol esters in these cells and the current work was undertaken primarily to establish whether it is also subject to homologous regulation. In acute experiments, PACAP27-stimulated cAMP accumulation (intracellular plus extracellular) was measured (in the presence of phosphodiesterase inhibitor) both in intact cells and in cell membranes. The peptide increased cAMP accumulation, but initial rates of PACAP27-stimulated cAMP accumulation were reduced to between 10 and 50% within 10 min of stimulation in both cells and membranes. The initial rate of forskolin-stimulated cAMP accumulation was maintained in membranes but not in intact cells (although the deviation from linearity was less pronounced than with PACAP27). Thus, rapid homologous desensitization to PACAP27 occurs in intact αT3-1 cells, but is not entirely receptor specific. Rapid homologous desensitization of PACAP27-stimulated cAMP accumulation also occurred in the presence of a protein kinase C activating phorbol ester, which inhibited cAMP accumulation without altering the kinetics of the PACAP27 effect. Brief pre-treatment (3 min) with PACAP27 also reduced the ability of PACAP27, but not gonadotrophin-releasing hormone, to cause a spike-type elevation of cytosolic Ca2+ concentration (a consequence of phosphoinositidase C activation). In chronic desensitization studies, pre-treatment for 6 h with PACAP27 caused a dose-dependent (IC50 approximately 10 nM) reduction of PACAP-stimulated cAMP accumulation and down regulated cell surface PVR1 receptors (to approximately 50%). Thus, it appears that PACAP27-stimulated (PVR-1 receptor mediated) adenylyl cyclase undergoes rapid homologous desensitization in αT3-1 cells, which is paralleled by homologous desensitization of PACAP27-stimulated phosphoinositidase C activity and involves mechanisms distinct from those underlying heterologous desensitization by phorbol esters. Chronic desensitization of PACAP-stimulated cAMP accumulation and down-regulation of cell surface PVR-1 receptors also occurs in these cells although the receptor loss may not entirely explain the observed desensitization. 相似文献