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51.
Clotrimazole, an imidazole antimycotic, interferes with the rise in cytosolic Ca2+ and inhibits cell proliferation in a reversible manner. Here we describe the effect of clotrimazole on vascular endothelial cells (ECs). Clotrimazole inhibited the proliferation of ECs stimulated with typical angiogenic growth factors; vascular endothelial growth factor and basic fibroblast growth factor (bFGF). This inhibitory effect of clotrimazole was dose-dependent and the maximal inhibition was observed at a concentration of 10 m M . We did not observe any increase in 51Cr release from ECs during treatment with 10 μ M . clotrimazole. Moreover, clotrimazole inhibited the basal and bFGF-stimulated migration of ECs. As clotrimazole inhibited two principle components of angiogenesis; the proliferation and migration of ECs, we examined whether clotrimazole inhibited angiogenesis. Tube formation by ECs in type 1 collagen gel was investigated, and clotrimazole was found to be significantly inhibitory. The inhibitory effect of clotrimazole on angiogenesis was further confirmed in an in vivo angiogenesis model of murine Matrigel plug assay. These results demonstrate that clotrimazole is a potent inhibitor of angiogenesis.  相似文献   
52.
OBJECTIVE: Vacuolar H(+)-adenosine triphosphatase plays a pivotal role in pH regulation and molecular transport across the vacuolar membranes and is involved in cell proliferation and transformation. In the present study, possible involvement of vacuolar H(+)-adenosine triphosphatase in neointimal formation was investigated in an organ culture model of human saphenous vein. Methods and results: Cultured saphenous vein segments developed neointimal formation and marked thickening of the media within 14 days. Neointimal formation and medial thickening were completely inhibited by 10 nmol/L bafilomycin A(1), a selective inhibitor of vacuolar H(+)-adenosine triphosphatase, although structurally related macrolide antibiotics FK-506 and erythromycin were without an effect. The neointimal cells were positive for alpha-smooth muscle actin and vimentin but negative for desmin, indicative of myofibroblasts. The emergence of myofibroblasts was inhibited, and endothelial cells were preserved in the saphenous vein segments treated with bafilomycin A(1). Uptake of bromodeoxyuridine, a proliferation marker, by myofibroblasts was abrogated in the saphenous vein segments treated with 10 nmol/L bafilomycin A(1). Detection of apoptotic cells by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling concomitant with identification of desmin-expressing smooth muscle cells demonstrated that neointimal myofibroblasts, but not medial smooth muscle cells, that expressed desmin underwent apoptosis by treatment with bafilomycin A(1). CONCLUSIONS: These results suggest that vacuolar H(+)-adenosine triphosphatase may be involved in myofibroblast growth that contributes to neointimal formation and medial thickening in cultured human saphenous vein. Increased sensitivity of myofibroblasts, but not endothelial cells, and differentiated smooth muscle cells to bafilomycin A(1) may have potential therapeutic implications in the treatment for vein graft disease.  相似文献   
53.
We investigated whether the species difference in the biliary excretion activity of some Mrp2 substrates was attributable to the intrinsic transport potential or the expression level of Mrp2, especially in rat and dog. Dog Mrp2 cDNA was isolated from beagle dog liver, and a vesicle transport study was performed using recombinant rat and dog Mrp2 expressed in insect Sf9 cells. The ATP-dependent transport of 17beta-estradiol 17-(beta-D-glucuronide) ([3H]E(2)17betaG) and leukotriene C4 ([3H]LTC4), normalized by the absolute protein expression level, was similar in both Mrp2s. The Mrp2 protein expression in dog liver was only 10% of that in rat liver and was comparable with the reported difference in the biliary excretion clearance of temocaprilat as Mrp2 substrate. In contrast to LTC4, unique transport kinetics for E(2)17betaG were evident in dog Mrp2. In addition to the high-affinity site with a K(m) value of 3.25 +/- 0.10 microM, which is similar to that in rat Mrp2 (4.81 +/- 1.21 microM), dog Mrp2 has an additional low-affinity site (>75 microM), which makes a major contribution to the transport of E(2)17betaG (65% of the total transport capacity at tracer concentration). In summary, the difference in the biliary excretion activity of Mrp2 substrates between rat and dog depends on the Mrp2 protein expression level rather than the intrinsic transport activity of the transporter molecules. The unique transport properties of glucuronide conjugates by dog Mrp2 may lead to the species difference involving the drug-drug interaction or drug-induced hyperbilirubinemia on the bile canalicular membrane.  相似文献   
54.
A patient with recurrent gastric cancer which infiltrated the pelvic muscle after the treatment of paraaortic lymph node and ovarian metastases was successfully managed by a novel oral anticancer drug, TS-1. TS-1 was administered at a dose of 80 mg/day. One course consisted of two repetitions of consecutive administration of TS-1 for 14 days and withdrawal of TS-1 for 14 days. Adverse reactions were mild and the patient did not request hospitalization after two courses had been completed. Subjective symptoms such as difficulty in walking improved after one week and a partial response was obtained after 2 weeks of treatment. At the end of 4 courses we could remove an indwelling pyelocatheter for the ureter stricture. As of 14 months after the beginning of administration of TS-1, the patient is being treated as an outpatient and has attained a better QOL than before.  相似文献   
55.
Hepatoma-derived growth factor (HDGF), unrelated to hepatocyte growth factor, is a heparin-binding protein originally purified from human hepatoma HuH-7 cells. HDGF exhibits mitogenic activities for certain hepatoma cells, fibroblasts and vascular smooth muscle cells, and angiogenic activities through nuclear targeting. Recently, HDGF was found to be a mitogen for lung epithelial cells in vitro and in vivo. This suggests that HDGF may play a critical role in the development and progression of lung cancer. We investigated, immunohistochemically, the relationship between HDGF expression and clinicopathological variables, and the prognostic significance of HDGF in 102 patients with completely resected non-small-cell lung cancer (NSCLC: 70 adenocarcinomas and 32 squamous cell carcinomas). To address the mechanism of action of HDGF, we evaluated the contribution of HDGF to tumor cell proliferation and intratumor angiogenesis using anti-Ki-67 and anti-CD31 antibodies, respectively. HDGF expression was strongly detected in the nucleus of cancer cells; the HDGF-labeling index (LI) was 20-95% (median 64.5%). There was no significant association between HDGF-expression level and clinicopathological variables. Patients with NSCLC showing a high HDGF-LI (> or =65%) had significantly worse overall and disease-free survivals than those with NSCLC showing a low HDGF-LI. Multivariate analysis revealed that HDGF is a significant independent prognostic factor, more powerful than pathological stage. Moreover, HDGF expression correlated with Ki-67-LI and intratumor microvessel density. We consider HDGF as a useful prognostic marker for patients with completely resected NSCLC and it may play a critical role in the pathobiology of lung cancer through its mitogenic and angiogenic activities.  相似文献   
56.
Purpose: This multicenter phase II study was conducted to investigate the efficacy and safety of carboplatin in combination with paclitaxel administered according to a biweekly schedule as a first-line chemotherapy for advanced non-small-cell lung cancer (NSCLC). Patients and methods: Eligibility criteria included histologically or cytologically confirmed NSCLC (stage IIIb or IV), no prior treatment, and measurable or evaluable disease. Paclitaxel (140 mg/m2) was administered intravenously on day 1, in combination with carboplatin at an area under the concentration time curve (AUC) of 3, every 2 weeks. Results: Seventy-four patients (45 men) with a median age of 62 years (range 40–74) and a median ECOG performance status of 1 (range 0–2) were enrolled. The response rate was 35.1% [95% confidence interval (CI): 24.4–47.1%], with 26 partial responses. The median survival was 357 days, and the median time to progression was 218 days. Toxicity was generally mild; National Cancer Institute-Common Toxicity Criteria (NCI-CTC) grades 3 and 4 neutropenia was observeded in 50.0% of the patients, and grades 3 and 4 nausea/vomiting in 4.1%. Conclusions: Biweekly carboplatin combined with paclitaxel demonstrated anti-tumor activity in advanced NSCLC, with response and survival rates similar to those of carboplatin combined with paclitaxel administered every 3 weeks but with a more favorable toxicity profile, and the present data indicate that the regimen is suitable for use on an outpatient basis.  相似文献   
57.
58.
Simple and rapid analysis of aristolochic acid (AA) in crude drugs and Kampo extracts using a solid-phase extraction method and HPLC-PDA analysis was investigated. Extraction of AA from samples was accomplished by adding methanol containing 1% ammonia. The addition of ammonia ionized the AA of acidic substances so that they adhered to an acrylamide copolymer of a strong anion exchange resin (Sep-Pak QMA) coupled to diol silica easily. Furthermore, a mixture of acetonitrile–water–phosphoric acid (75:25:2, v/v) was effective in isolating AA from its carrier. Since almost all interfering peaks originating from contaminants in crude drugs and Kampo extract formulations could be removed, a satisfactory HPLC chromatogram of AA was obtained. A good result was also obtained when Aristolochiaceae and crude drugs containing AA were tested. Particularly in the case of the medicinal parts of Asarum, several interfering peaks and a ghost peak detected near the AA peak were eliminated. The AA contents of two Kampo extract formulations, tokishigyakukagoshuyushokyoto and ryutanshakanto, were calculated by HPLC analysis. The AA content (the sum of AA-I and AA-II) was 1.25–6.13 mg per daily dose. From an additional recovery experiment for Kampo formulations, high recovery rates of AA were obtained. Neither LC/MS nor special instrumentation was necessary. Our results suggest that this simple, quick, and sensitive analytical method to detect AA in crude drugs and Kampo extract formulations would be valuable in safety inspections of AA in crude drugs and their products.  相似文献   
59.
Free and acylcarnitine in serum and urine samples were measured in five patients with hyperammonemia associated with anticonvulsant therapy including sodium valproate, of whom three had a Reye-like syndrome. All had considerable reduction in serum free carnitine and slight increase of acylcarnitine concentrations, suggesting increased conversion of free to acylcarnitine by valproate administration. Urinary excretion of both free and acylcarnitine was increased, accompanied by depressed reabsorption of free carnitine and decreased acylcarnitine/free carnitine clearance ratio. These results indicate a decreased threshold for free carnitine. The combination of these several factors may be responsible for carnitine deficiency in patients with hyperammonemia taking valproate.  相似文献   
60.
Background and aim:Acute exacerbation (AE) of idiopathic pulmonary fibrosis (IPF) is a fatal condition with no established treatment. Intravenous immunoglobulin (IVIG) is a unique therapy with both anti-inflammatory and anti-infective effects. Therefore, we hypothesized that IVIG may have a positive effect on AE of interstitial pneumonia. This study aimed to determine the effect of IVIG in patients with AE of fibrotic idiopathic interstitial pneumonias (IIPs), including IPF.Methods:We retrospectively analyzed consecutive patients who were diagnosed with AE of fibrotic IIPs and treated with pulse corticosteroid therapy (methylprednisolone 500–1000 mg/day for 3 days) between April 2018 and May 2021 at Kagawa Rosai Hospital and KKR Takamatsu Hospital.Results:This study included 52 patients with AE of fibrotic IIPs (IPF,41; fibrotic IIPs other than IPF,11). Thirteen patients received IVIG (5 g/day for 3–5 days) concurrently with pulse corticosteroid therapy. The remaining 39 patients were assigned to the control group. The survival rate on day 90 was significantly higher in the IVIG group than that in the control group (76.9% vs. 38.5%, p = 0.02). IVIG administration (odds ratio [OR], 0.11; 95% confidence interval [CI], 0.02–0.69; p = 0.02) and C- reactive protein (OR, 1.19; 95% CI, 1.06–1.33, p < 0.01) were independently associated with 90-day mortality.Conclusions:The results indicate that administration of IVIG may improve the survival of patients with AE of fibrotic IIPs. We are now conducting a prospective study to confirm the effect of IVIG on AE of IPF since May 2022 (jRCT1061220010).  相似文献   
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