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111.
Naratriptan: biological profile in animal models relevant to migraine   总被引:2,自引:0,他引:2  
The biological profile of naratriptan (N-methyl-3-(1-methyl-4-piperidinyl)-1H-indole-5-ethane-sulphona-mide), a novel 5HT1B/1D receptor agonist, was investigated in a variety of experimental models of relevance to migraine. Naratriptan has high affinity for human recombinant 5HT1B and 5HT1D receptors (pKi = 8.70.03 and 8.30.1, respectively) and causes contractions of dog isolated basilar and middle cerebral artery (EC50 values of 0.11 and 0.07 M, respectively). Naratriptan causes small contractions of human isolated coronary arteries (EC50 value of 0.17 M; maximum contraction equivalent to 33% of 5HT maximum). In anaesthetized dogs, naratriptan causes selective vasoconstriction of the carotid arterial bed (CD50 dose = 193 g kg−1) and, in anaesthetized rats, naratriptan selectively inhibits neurogenic plasma protein extravasation in the dura (ID50 = 4.1 g kg−1). In a variety of antinociceptive tests, naratriptan has no effect even at high doses. In conscious rats and dogs, naratriptan has high oral bioavailability (71% and 95%, respectively). The data show that naratriptan is a selective agonist at 5HT1B/1D receptors, with a pharmacological profile very similar to that of sumatriptan, albeit 2-3 fold more potent. These observations, coupled with high oral bioavailability in animals, suggest that naratriptan has the profile of an orally effective anti-migraine drug.  相似文献   
112.

Background  

Rearrangement of the short arm of chromosome 8 (8p) is very common in epithelial cancers such as breast cancer. Usually there is an unbalanced translocation breakpoint in 8p12 (29.7 Mb – 38.5 Mb) with loss of distal 8p, sometimes with proximal amplification of 8p11-12. Rearrangements in 8p11-12 have been investigated using high-resolution array CGH, but the first 30 Mb of 8p are less well characterised, although this region contains several proposed tumour suppressor genes.  相似文献   
113.
HIV-1-infected patients exhibit severe damages of the aortic endothelium, develop angioproliferative lesions such as Kaposi's sarcoma (KS), and have an increased risk of cardiovascular diseases and atherosclerosis. An increased adhesion of leukocytes to the endothelium is a common pathogenic parameter of AIDS-associated vascular diseases. Here we show that the HIV-1 Tat protein, a regulatory protein of HIV-1 released by infected cells, and TNF-alpha, a cytokine increased in sera and tissues of HIV-1-infected patients, activate synergistically the adhesion of leukocytes to endothelial cells both in vitro and in vivo. This effect is selectively mediated by HIV-1 Tat, since HIV-1 Nef, another HIV-1 regulatory protein, and the HIV-1 envelope protein gp41, had no effect. In vitro adhesion assays with PBMC and quantitative cell type analysis of adherent cells by FACS demonstrated that HIV-1 Tat selectively activates the adhesion of T-cells and monocytes but not of B-cells. Intravital microscopic studies in mice confirmed the synergistic activity of HIV-1 Tat and TNF-alpha on leukocyte adhesion to the endothelium in vivo. These data indicate that HIV-1 Tat in cooperation with TNF-alpha may contribute to the vascular damage and cardiovascular diseases observed in AIDS patients but also to the prominent extravasation of T-cells and monocytes which is a key process in the formation and progression of KS lesions.  相似文献   
114.
The aim of this phase I/II nonrandomized trial was to assess feasibility, safety as well as immunological and clinical responses of a mRNA-based vaccination in patients with stage IV renal cell cancer using granulocyte-macrophage colony stimulating factor (GM-CSF) as adjuvant. Intradermal injections of in vitro transcribed naked mRNA, which was generated using plasmids coding for the tumor-associated antigens mucin 1(MUC1), carcinoembryonic (CEA), human epidermal growth factor receptor 2 (Her-2/neu), telomerase, survivin, and melanoma-associated antigen 1 (MAGE-A1) were performed in 30 enrolled patients. In the first 14 patients (cohort A) vaccinations were administered on days 0, 14, 28, and 42 (20 µg/antigen) while in the consecutive 16 patients (cohort B) an intensified protocol consisting of injections at days 0–3, 7–10, 28, and 42 (50 µg/antigen) was used. In both cohorts, after this induction period, vaccinations were repeated monthly until tumor progression analyzed by Response Evaluation Criteria In Solid Tumors criteria (RECIST). Vaccinations were well tolerated with no severe side effects and induced clinical responses [six stable diseases (SD) and one partial response in cohort A and nine SD in cohort B]. In cohort A, 35.7% survived 4 years (median survival 24 months) compared to 31.25% in cohort B (median survival 29 months). Induction of CD4+ and CD8+ T cell responses was shown for several tumor-associated antigens (TAA) using interferon-γ (IFN-γ) enzyme-linked immunosorbent spot (ELISpot) and Cr-release assays.  相似文献   
115.
Prior to 1990, many patients with inherited bleeding disorders were infected with hepatitis C virus (HCV). This study assessed the risk of end-stage liver disease (ESLD) in patients with hemophilia with chronic hepatitis C. Patients were infected between 1961 and 1990 and were followed up to August 2005. Of 847 anti-HCV(+) patients, 160 (19%) spontaneously cleared HCV and 687 (81%) developed chronic hepatitis C. Coinfection with HIV was present in 210 patients. After 35 years of infection the cumulative incidence of ESLD was 11.5% (95% CI, 8.2%-14.8%) in HIV(-) patients and 35.1% (95% CI, 29.2%-41.0%; P < .001) in patients coinfected with HIV. Independent risk factors of ESLD were HIV coinfection (hazard ratio 13.8; 95% CI, 7.5-25.3), older age at infection (hazard ratio 2.3 per 10 years; 95% CI, 2.0-2.8), alcohol abuse (hazard ratio 4.9; 95% CI, 2.5-9.6), and presence of HCV genotype 1 (hazard ratio 2.2; 95% CI, 1.1-4.2). With longer duration of HCV infection, the risk of developing ESLD is emerging in patients with inherited bleeding disorders. Risk factors for rapid progression to ESLD are alcohol abuse, coinfection with HIV, older age at infection, and presence of HCV genotype 1.  相似文献   
116.
117.
Expression of HLA antigens and beta 2-microglobulin was studied by immunoperoxidase staining of frozen sections of 9 mucinous and 10 nonmucinous colorectal adenocarcinomas, 1 cloacogenic carcinoma, 12 colorectal adenomas and 4 samples of normal colorectal mucosa using monoclonal antibodies (MAbs). Staining results were related to histopathological features. HLA Class I antigens were strongly expressed in morphologically normal colorectal epithelium, in all adenomas tested and in all non-mucinous carcinomas. In contrast, expression of HLA class I antigens by the majority of tumour cells was present in only 2 of the 9 mucinous carcinomas, whereas 2 of these mucinous carcinomas were completely negative. In the mucinous carcinomas a striking scarcity of mononuclear inflammatory infiltrate, especially around the mucus accumulations, was observed. HLA class II antigen expression was not detected in normal epithelium and was only focally present in 1 of the 12 adenomas. In 6 out of the 20 carcinomas tested between 20% and 90% of the tumour cells were stained by MAbs against HLA class II antigens. Apart from the low expression of HLA class I antigens in mucinous carcinomas no relationship was found between expression of HLA antigens and histological features of the tumours. The relative poor prognosis of mucinous colorectal carcinoma as reported in the literature may be associated with low expression of HLA class I antigens and scant mononuclear inflammatory infiltrate, which may be a reflection of a weak immune response to the tumour cells.  相似文献   
118.
Linkage studies on familial adenomatous polyposis (FAP) reported so far suggest that FAP is a genetically homogeneous disease. Recently, we found that the putative gene for Turcot syndrome, an apparently autosomal recessive clinical variant of FAP, is not allelic to FAP. Here we describe another family, segregating for an autosomal dominant disease clinically indistinguishable from FAP but genetically not linked to the APC locus, adding further evidence for the occurrence of non-allelic heterogeneity of FA. These observations have implications to the linkage-based genetic counselling of persons at risk for FAP especially when they are drawn from small families giving insufficient information. © 1993 Wiley-Liss, Inc.  相似文献   
119.
PURPOSE: Metallothionein (MT) is a small protein with a high affinity for divalent heavy metal ions. This metalloproteinis involved in many (patho)physiological processes, like metal homeostasis and detoxification, cell proliferation, apoptosis, therapy resistance, and protection against oxidative damage. Alterations in the immunohistochemical expression of MT have been reported for various human tumors, and a high expression has been found to be associated with a poor clinical outcome. We showed previously that gastrointestinal cancer is accompanied by a decrease in MT expression, but the most malignant phenotypes had the highest MT levels. The purpose of the present study was to assess the clinical relevance of MT in gastrointestinal cancer. EXPERIMENTAL DESIGN: In this study, we determined the MT levels, by radioimmunoassay, in intestinal tissue of 251 patients with colorectal cancer and 81 patients with gastric cancer and assessed the relation with the overall survival of these patients. RESULTS: More than 74% of the carcinomas were found to have a lower MT level than their corresponding normal mucosa. In colorectal cancer patients, but not in gastric cancer patients, a high MT level in both the carcinomas and normal mucosa was, however, significantly associated with a poor overall survival, independently from clinicopathological features. CONCLUSIONS: Overexpression of MT in intestinal tissue of colorectal cancer patients is a prognostic marker for a poor overall survival. In gastric cancer, however, MT expression in the gastric mucosa is not of prognostic significance. This observation emphasizes the clinical relevance of this multifunctional metalloprotein in colorectal carcinogenesis and therapy.  相似文献   
120.
Although there have been great advances in cancer diagnosis in recent years, it remains difficult to transfer tumor location information from cross-sectional computed tomographic (CT) scans or magnetic resonance images to the simulation and verification films used in planning radiotherapy. A newly developed system uses radioopaque markers attached to the patient as reference points. These markers are identified on both CT scans and simulation films and their locations entered into the treatment planning computer. The tumor and any desired normal structures are then outlined manually on each CT section. Transparent overlays produced by the computer show the position of the reference markers and tumor outlines for any combination of gantry angles and source-film distance. Because the overlays are scaled to the simulation films, the reference points enable precise alignment of overlay and film. The tumor outline thus appears on the simulation or verification films exactly as it is "seen" by the therapy beam, making field verification straightforward and accurate, even on oblique films.  相似文献   
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