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A monoclonal antibody (MoAb, SK-930) of the IgG2a subclass to human pancreatic carcinoma cells (MIA-PaCa 2) was obtained by hybridization of spleen cells from immunized Balb/c mice with murine myeloma cells. SK-930 was investigated for reacting in indirect immunofluorescence on FACS against a panel comprising 12 types of different origin. SK-930 reacted with seven out of 11 tumor cells and with one PBL. Immunoperoxidase techniques (ABC method) showed that SK-930 antigen was present on pancreatic adenocarcinoma cells, but could not be detected on normal pancreatic tissue. Immunoprecipitation experiments and SDS-PAGE analysis revealed that SK-930 recognized 134K dalton peptide on tumor cells. These results suggest that SK-930 reacts with a novel pancreatic cancer-associated antigen.  相似文献   
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Background and Objective: To further understand the precise process of the tumor cell degeneration after photodynamic therapy (PDT), laser hyperthermic therapy (LH), and combined treatments using an Nd:YAG laser. It is important to examine initial morphological alteration of tumor cells after these treatments. Study Design/Materials and Methods: In this study, nude mice bearing HeLa cell tumors were treated with PDT, LH, and combined treatments of the two. Tumor tissues obtained immediately after these treatments were analyzed using electron microscopy and morphometry. Results: In the combined treatments, which produced more severe effects on tumor cells, morphological features of apoptosis such as cytoplasmic condensation, blebs, and apoptotic bodies appeared in the cells, although the typical alteration in the nuclear chromatin was not seen. Conclusion: Cytoplasmic alterations may proceed more rapidly than nuclear alterations in the cellular degeneration induced by the single or combined treatments of PDT and LH.  相似文献   
4.
Five gastric adenocarcinomas and their metastatic nodules in the liver with high serum AFP levels were examined by histologic and immunohistochemical methods. The examination revealed that AFP-producing stomach cancers were poorly differentiated carcinoma cells, especially with medullary arrangements, or pleomorphic or multinucleated giant cells. Well-differentiated papillotubular adenocarcinoma tissues on the glandular epithelium were not stained with anti-AFP. One out of the five AFP-producing adenocarcinomas with medullary patterns resembled liver cell carcinoma on light microscopy. However, an ultrastructural study showed tumor cells of the intestinal type, since the cells possessed a ductal lumina with abundant microvilli and a secretory granules. The findings suggest that the tumor cells differentiated in an intestinal direction rather than hepatic direction. In addition, we noted three simultaneously CEA-positive cases out of five AFP-producing gastric carcinomas. CEA was strongly stained in well differentiated adenocarcinoma tissues in the glandular epithelium or in areas of medullary type carcinoma invasion. However, CEA was not detected in undifferentiated carcinoma cells.  相似文献   
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BACKGROUND: Inflammation has been proposed to play essential roles in the pathophysiology of endometriosis, in which neutrophils and mast cells have been suggested to be involved. We studied whether the protease-activated receptor 2 (PAR2), which is activated by enzymes from neutrophils and mast cells, in endometriotic stromal cells (ESC) has any implication in the development of the disease. METHODS: Cultured ESC were stimulated with various concentrations of a specific PAR2 agonist peptide. Proliferating activity of the cells was determined using immunostaining of proliferating cell nuclear antigen (a cell proliferation marker), 5-bromo-2'-deoxyuridine incorporation into DNA and cell count. The concentrations of interleukin (IL)-6 and IL-8 were measured using specific enzyme-linked immunosorbent assay kits. The phosphorylation of three mitogen-activated protein kinases (MAPK), i.e. p38 MAPK, p42/44 MAPK and stress-activated protein Kinase/c-jun N terminal Kinase, in ESC was examined with Western blot analysis. RESULTS: Activation of PAR2 stimulated the proliferation of ESC and the secretion of IL-6 and IL-8 from ESC in a dose-dependent manner. Activation of PAR2 stimulated the phosphorylation of all three MAPK, and inhibitors of each MAPK suppressed the PAR2 activation-induced proliferation of ESC. CONCLUSIONS: The activation of PAR2 in ESC may be involved in the pathophysiology of endometriosis by inducing the growth and inflammation of endometriotic lesions.  相似文献   
6.
Tumour necrosis factor alpha (TNFalpha), a proapoptotic cytokine, is known to be present in peritoneal fluid from women with endometriosis. An emerging view is that soluble TNF receptors (sTNFR) can modulate the effects of TNFalpha by acting as TNFalpha antagonists. To assess the relevance of sTNFRs in the pathophysiology of endometriosis, concentrations of sTNFR I, sTNFR II and TNFalpha in peritoneal fluid from women with endometriosis (n = 53) and without endometriosis (n = 40) were measured. Concentrations of both sTNFR I and sTNFR II in peritoneal fluid from women with endometriosis were significantly higher than in peritoneal fluid from women without endometriosis, both in the follicular and the luteal phases. TNFalpha concentrations did not differ in patients with and without endometriosis in both phases. When stratified by the stage of the disease, women with both stages I/II and stages III/IV exhibited significantly higher concentrations of sTNFR I and sTNFR II in peritoneal fluid, compared with women without endometriosis, whereas no appreciable difference in the concentrations was detected between stages I/II and stages III/IV. A significant correlation was found between the concentrations of sTNFR I and sTNFR II; while the correlations between TNFalpha and sTNFR I or sTNFR II, were either not significant or were very weak. Furthermore, mRNA for the membrane-associated TNF receptor type 1 and TNF receptor type 2, both of which convey the effects of TNFalpha, were shown to be expressed in endometriotic tissues as well as eutopic endometrium. Together, these findings suggest a possible involvement of sTNFRs in the pathophysiology of endometriosis.  相似文献   
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PurposeTo investigate and compare venous sac and feeding artery embolization (VFE) with feeding artery embolization (FAE) alone for treatment of pulmonary arteriovenous malformations (PAVMs), based on difference in outcomes in decrease of the size of the draining vein.Materials and MethodsTwenty-six patients (7 male and 19 female; median age [interquartile range], 58 years [46–65 years]) with 42 simple PAVMs treated with coil embolization between August 2005 and December 2018 were retrospectively evaluated. Twenty PAVMs were treated with FAE early in the study period and compared with 22 PAVMs treated with VFE later in the study period. Follow-up computed tomography images obtained 8–20 months after embolotherapy were used for outcome analysis. Data related to patient demographics; follow-up period; baseline diameters of the feeding artery, venous sac, and draining vein; draining vein diameter after treatment; and decrease in the size of the draining vein, including the number reaching a threshold of 70% decrease, were compared between the 2 groups.ResultsThe draining vein decreased in size by a median of 46.4% in the FAE group and 66.3% in the VFE group, and the difference between the 2 groups was statistically significant (P = .009). There were no significant differences in the other parameters.ConclusionsVFE leads to a greater decrease in the size of the draining vein than FAE, suggesting that VFE results in more complete occlusion than FAE for treatment of PAVMs.  相似文献   
9.

Purpose  

The purpose of this retrospective study was to investigate the efficacy of transarterial chemoembolization (TACE) using cisplatin as a second-line treatment for advanced hepatocellular carcinoma (HCC) unresponsive to TACE using epirubicin–Lipiodol emulsion at our institution.  相似文献   
10.
Periostin/OSF2 is a ligand for alphavbeta3 and alphavbeta5 integrins and activates the Akt/PKB pathway. Recent reports of periostin/OSF2 gene disrupted mice indicate that periostin/OSF-2 plays an important role in implantation. Quantitative RT-PCR revealed that the expression of periostin/OSF-2 mRNA in rat uteri was reduced to approximately 10% at 12 h after 17beta-estradiol (E2) injection, but was not changed after progesterone (P) injection. RT-PCR revealed the expression of periostin/OSF-2 in human endometrium, cultured human endometrial stromal cells (ESCs), and cultured human endometrial epithelial cells. In ESCs, the expression of periostin/OSF-2 mRNA was reduced to approximately 50% at 6 h after E2 treatment. The amount of periostin/OSF2 mRNA in human endometrium significantly increased during mid-proliferative and early secretory phases of menstrual cycle, and decreased during late-proliferative, mid-secretory and late secretory phases. The expression of periostin/OSF2 mRNA significantly decreased in ESCs decidualized by treatment with E2 and P for 7 and 11 days. By immunohistochemistry, the expression of periostin/OSF-2 was strongly detected in endometrial stromal cells during early proliferative, mid-proliferative and early secretory phases, and was strongly detected in endometrial epithelial cells during late secretory phase. This study demonstrated that the expression of periostin/OSF-2 is regulated by ovarian steroid hormones in rat uterus and human endometrium.  相似文献   
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