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61.
62.
Vascular Ehlers–Danlos syndrome (vEDS) is a hereditary connective tissue disorder (HCTD) characterized by arterial dissection/aneurysm/rupture, sigmoid colon rupture, or uterine rupture. Diagnosis is confirmed by detecting heterozygous variants in COL3A1. This is the largest Asian case series and the first to apply an amplification-based next-generation sequencing through custom panels of causative genes for HCTDs, including a specific method of evaluating copy number variations. Among 429 patients with suspected HCTDs analyzed, 101 were suspected to have vEDS, and 33 of them (32.4%) were found to have COL3A1 variants. Two patients with a clinical diagnosis of Loeys–Dietz syndrome and/or familial thoracic aortic aneurysm and dissection were also found to have COL3A1 variants. Twenty cases (57.1%) had missense variants leading to glycine (Gly) substitutions in the triple helical domain, one (2.9%) had a missense variant leading to non-Gly substitution in this domain, eight (22.9%) had splice site alterations, three (8.6%) had nonsense variants, two (5.7%) had in-frame deletions, and one (2.9%) had a multi-exon deletion, including two deceased patients analyzed with formalin-fixed and paraffin-embedded samples. This is a clinically useful system to detect a wide spectrum of variants from various types of samples.  相似文献   
63.
Overexpression of P-glycoprotein (Pgp) in tumors is one of the major mechanisms which mediates the multidrug resistance (MDR) phenotype. To evaluate the prognostic significance of Pgp in breast cancer, Pgp expression was examined in paraffin-embedded tissue sections of 94 breast cancer specimens by immunohistochemistry. Tissue specimens were obtained by mastectomy without preoperative chemotherapy. UIC2 monoclonal antibody which recognizes an extracellular epitope of human Pgp was employed. Of the 94 breast cancer specimens, 35 (37.2%) were positive for Pgp expression. Pgp expression had no correlation with menopausal or hormone receptor status, axillary lymph node involvement or tumor size. However, a significant correlation was observed between Pgp expression and disease relapse (p = 0.0322). Pgp-positive patients showed a significantly shorter disease-free survival period than Pgp-negative patients by the Kaplan-Meier method (p = 0.0433). These results suggest that immunohistochemical detection of Pgp in breast cancer tissue may have prognostic value after radical operation.  相似文献   
64.
Liver Targeting of Interferon Through Pullulan Conjugation   总被引:1,自引:0,他引:1  
Xi  Keli  Tabata  Yasuhiko  Uno  Kazuko  Yoshimoto  Miwa  Kishida  Tsunataro  Sokawa  Yoshihiro  Ikada  Yoshito 《Pharmaceutical research》1996,13(12):1846-1850
Purpose. The purpose of this study was to actively target interferon (IFN) to the liver through its chemical conjugation with pullulan, a water-soluble polysaccharide with a high affinity for the liver. Methods. Chemical conjugation of IFN with pullulan was achieved by a cyanuric chloride method. Following intravenous injection of the conjugates to mice, their body distribution and the activity of an IFN-induced enzyme, 2,5-oligoadenylate (2-5A) synthetase in the liver and other organs, were evaluated. Results. The cyanuric chloride method enabled us to prepare an IFN-pullulan conjugate that retained approximately 7–9 % of the biological activity of IFN. Pullulan conjugation enhanced the liver accumulation of IFN and the retention period with the results being reproducible. When injected intravenously to mice, the IFN-pullulan conjugate enhanced the activity of 2-5A synthetase in the liver. The activity could be induced at IFN doses much lower than those of free IFN injection. In addition, the liver 2-5A synthetase induced by conjugate injection was retained for 3 days, whereas it was lost within the first day for the free IFN-injected mice. Conclusions. IFN-pullulan conjugation was promising for IFN targeting to the liver with efficient exertion of its antiviral activity therein.  相似文献   
65.
It has been shown that administration of cigarette smoke to rats leads to loss of neuronal nitric-oxide synthase (nNOS) activity and nNOS protein in penile tissue. The exact mechanism for this loss of activity and protein is not known. In the current study, we investigated whether extracts prepared from cigarette smoke or from the cigarette itself could directly inhibit nNOS activity. We discovered that the cigarette smoke extract and the cigarette extract cause a time-, concentration-, and calmodulin-dependent inactivation of nNOS in an in vitro system containing the purified enzyme. L-Arginine, but not D-arginine, protects nNOS from this time-dependent inactivation, suggesting an active site directed event. The kinetics of inactivation are consistent with the metabolism-based or suicide inactivation of nNOS. Based on studies with other metabolism-based inactivators, this cigarette-mediated inactivation may render nNOS more susceptible to proteasomal degradation and thereby may explain the loss of nNOS protein in vivo. The component(s) responsible for nNOS inactivation is not volatile, is not retained by a 3,000 molecular weight cut-off membrane, binds to activated charcoal, and is highly water-soluble under both acidic and basic conditions. The discovery of a direct inactivation of nNOS by an organic, cationic compound(s) present in tobacco and tobacco smoke provides a basis for further study of not only the mechanisms responsible for the biological effects of tobacco but also a search for a potentially novel inactivator of nNOS.  相似文献   
66.
PURPOSE: Valosin-containing protein (VCP; also known as p97) was shown to be associated with antiapoptotic function and metastasis via activation of nuclear factor kappa-B signaling pathway. In this study, association of VCP expression with recurrence of gastric carcinoma (GC), in which lymphatic vessels are the main route of spread, was examined. PATIENTS AND METHODS: VCP expression in 330 patients with GC (242 males and 88 females) with ages ranging from 26 to 81 years (median, 60 years) was analyzed by immunohistochemistry, in which staining intensity in tumor cells was categorized as weaker (level 1) or equal to or stronger (level 2) than that in endothelial cells. RESULTS: Ninety-four (28.7%) patient cases showed level 1 and 233 patient cases (71.3%) showed level 2 VCP expression. Patients with level 2 expression showed higher rates of large tumor size (P <.0001), undifferentiated histologic subtype (P <.05), presence of vascular and lymphatic invasion (P <.0001 for both), presence of lymph node metastasis (P <.0001), deep tumor invasion (P <.0001), and poorer disease-free and overall survivals (P <.0001 for both) compared with those with level 1 VCP expression. Multivariate analysis revealed VCP expression level as an independent prognosticator for disease-free and overall survival. VCP level was an indicator for disease-free and overall survival in the early (pT1; P <.01 and P <.05, respectively) and advanced (pT2-4; P <.05 for both) group of pathologic tumor-node-metastasis system classification. CONCLUSION: The prognostic significance of VCP expression level in GC was demonstrated.  相似文献   
67.
68.
Antitumor and antimetastatic activity of the angiogenesis inhibitor O-(chloroacetyl-carbamoyl) fumagillol (TNP-470), a semisynthetic analogue offumagillin, was evaluated in breast cancer cell lines. In an in vitro MTTassay, after 72 hrs continuous exposure to TNP-470, growth inhibition wasobserved in all seven cell lines of murine (JYG-A, JYG-B, DD-762, andBALB/c-MC) or human (KPL-1, MDA-MB-231, and MKL-F) origin, in which the50% inhibitory concentrations (IC50) at 72 hrstreatment were 4.6, 4.4, 4.6, 10.1, 35.0, 25.3, and 33.4 µg/ml,respectively. In an in vivo assay using JYG-A, JYG-B, KPL-1, and MDA-MB-231cells by orthotopic (right thoracic mammary fat pad) transplantation infemale nude mice, TNP-470 at 30 or 50 mg/kg body weight was injected s.c.every other day from the day of tumor cell inoculation until the end of theexperiment. The inhibitory effect on primary tumor growth was obtained inall four cell lines in a dose-dependent manner. In the 50 mg/kgTNP-470-treated group, the reductions in tumor weight of the JYG-A, JYG-B,KPL-1, and MDA-MB-231 cells with respect to the controls were 50%,30%, 4%, and 49%, respectively. Metastasis was seen inthe JYG-A, JYG-B, and KPL-1 cells. The numbers of mice bearing pulmonarymetastases of JYG-A and JYG-B cells and regional axillary lymph nodemetastases of KPL-1 cells were reduced, and TNP-470 at the 50 mg/kg dose toKPL-1 cells significantly reduced lymph node metastases compared with thecontrol. Although the weight gain was retarded in the TNP-470-treated mice,weight loss was not seen. TNP-470 was highly effective in the treatment ofbreast cancer cells. These results suggest that the clinical use of TNP-470may be a promising treatment for breast cancer patients.  相似文献   
69.
Paclitaxel and irinotecan are important new anticancer agents. The combination of these two agents has been considered for use against a variety of advanced solid tumors. Since the schedule-dependent effects of this combination may be crucial to its use, we studied the interaction of paclitaxel and SN-38 (the active metabolite of irinotecan) in various schedules in four human cancer cell lines in culture. Cell growth inhibition after 5 days was determined using an MTT assay. The effects of drug combinations at the IC80 level were analyzed by the isobologram method. Simultaneous exposure to paclitaxel and SN-38 for 24 h produced antagonistic (subadditive and protective) effects in the human lung cancer cell line A549, the breast cancer cell line MCF7, and the colon cancer cell line WiDr, and produced additive effects in the ovarian cancer cell line PA1. Sequential exposure to paclitaxel for 24 h followed by SN-38 for 24 h, and the reverse sequence, produced additive effects in all four cell lines. These findings suggest that sequential administration, not simultaneous administration, may be the appropriate schedule for the therapeutic combination of paclitaxel and irinotecan. Continued preclinical and clinical studies should provide further insights and assist in determining the optimal schedule for this combination in clinical use. Received: 25 February 1997 / Accepted: 6 November 1997  相似文献   
70.
The carcinoembryonic antigen (CEA) in the cyst fluid of ovarian mucinous and serous tumors was investigated. The molecular weight and antigenicity of the CEA from both ovarian tumors were very similar to those of colon cancer CEA as determined by SDS electrophoresis and double immunodiffusion on agar plates. In the cyst fluid of ovarian mucinous tumors, the amount of CEA was generally high and CEA of molecular weight (MW) 200,000 was increased. In contrast, in the cyst fluid of ovarian serous tumors, the CEA amount was low and CEA variants of MW 370,000 and 180,000 were present in addition to the main CEA of MW 200,000. Immunohistochemically, CEA was stained mainly in the intestinal type epithelium of ovarian mucinous tumors, and the CEA revealed a tendency to be stained more frequently and strongly with increasing degree of tumor malignancy. Thus, ovarian mucinous tumors (especially the intestinal type epithelium) produced large amounts of CEA which closely resembled colon cancer CEA, whereas ovarian serous tumors produced small amounts of CEA, including some CEA variants. In the study of ovarian epithelial tumors, CEA may be useful as a marker for the malignant transformation of ovarian mucinous tumors.  相似文献   
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