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Anthocyanins, which are responsible for a variety of bright colors (including red, blue, and purple) in fruits, vegetables, and flowers, are consumed as dietary polyphenols. Anthocyanin-containing fruits are thought to decrease coronary heart disease and are used in anti-diabetic preparations. Diabetes is associated with a variety of cardiovascular complications that may be mediated by endothelial dysfunction, and so this study was designed mainly to characterize the influence of a synthesized anthocyanidin derivative (HK-008) over acetylcholine (ACh)-induced relaxation in mesenteric arterial beds isolated from rats. In a glucose-tolerance test in intact rats, HK-008 (30 mg/kg) reduced the glucose level as effectively as the same dose of glibenclamide. The aortic relaxation induced by pinacidil (an ATP-sensitive potassium channel opener) was greatly inhibited by glibenclamide (10 microM), and also significantly inhibited by HK-008 (10 microM). Interestingly, the ACh-induced relaxation in the perfused, preconstricted mesenteric arterial bed was significantly enhanced by HK-008 (10 microM), and this enhancement was significantly attenuated by indomethacin (10 microM). The ACh-induced mesenteric relaxation was impaired by an increase in oxidative stress, viz. superoxide-generating treatment [xanthine oxidase (XO; 0.1 U/ml) plus hypoxanthine (HX; 10 microM)]. However, this impairment was strongly suppressed by HK-008 (10 microM). These results suggest that HK-008 increases endothelium-induced relaxation by suppressing oxidative stress or modulating prostanoids signaling. This compound may therefore be useful against certain cardiovascular disorders.  相似文献   
3.
One of the pyrimidine compounds, 2-piperadino-6-methyl-5-oxo-5,6-dihydro(7H)pyrrolo[3,4-d]pyrimidine (MS-818), has neurotropic effects in vitro. Therefore, we studied the effect of MS-818 on the regeneration of the peroneal nerve in C57BL/6J mice after a crush injury. Two test groups, which received a daily intraperitoneal injection of 5 mg/kg or 10 mg/kg MS-818, respectively, were compared with controls, which received daily intraperitoneal injections of physiological saline, over a 14-day period. The maximum foot-width ratio (crushed side/uncrushed side) was obtained on days 1, 8 and 14 after the crush injury, and the various morphometric parameters were evaluated at both 5 and 10 mm distal to the proximal portion of the crush site. The significant effects of MS-818 included a larger maximum foot width (P<0.04) and a greater number of unmyelinated axons per nerve at both levels (P<0.003) in both test groups than in controls. MS-818 had no significant effects on body weight, the increase of total transverse fascicular area after the crush injury, the total number of myelinated fibers with their size distributions, or the number of nuclei of Schwann cells and macrophages. Therefore, we conclude that MS-818 promotes axonal sprouting and elongation after a crush injury in mice.  相似文献   
4.
We examined the mechanisms of the inhibition of DNA synthesis by a new platinum compound, (-)-( R )-2-aminomethylpyrrolidine(1,1-cyclobutane-dicarboxylato)-2-platinum(II) monohydrate (DWA-2114R), a derivative of the antitumor drug cis- diamminedichloroplatinum(II) (CDDP), using prokaryotic and eukaryotic DNA polymerases. Preincubating activated DNA with CDDP or DWA-2114R reduced its template activity for prokaryotic and eukaryotic DNA polymerases in a dose-dependent manner. DWA2114R required six times greater drug concentration and two times longer incubation time to show the same decrease of the template activity compared to CDDP. Treatment of primed pUC118 ssDNA templates with the two drugs followed by second-strand synthesis by prokaryotic and eukaryotic DNA polymerases revealed that DWA2114R bound to DNA in a similar manner to CDDP and these adducts blocked DNA elongation by DNA polymerases of eukaryotes as well as of prokaryotes. With these two drugs, the elongations by E. coli DNA polymerase I (Klenow fragment), T7 DNA polymerase and calf thymus DNA polymerase α were strongly arrested at guanine-guanine sequences (GG). Stop bands were also observed at adenine-guanine sequences (AG) guanine-adenine-guanine sequences (GAG) and mono-guanine sequence (G). Calf testis DNA polymerase β was also arrested efficiently at AG, GAG and G, but much more weakly at GG. This pattern was common to DWA2114R and CDDP.  相似文献   
5.
A 16-year-old man was admitted to our hospital with nausea, general fatigue, and consciousness disturbance along with extreme hyperammoniemia eight days after the onset of symptoms. Familial history and the high concentration of orotic acid in urine lead us to a diagnosis of OTCD. We immediately initiated intensive treatment such as continuous hemodiafiltration and sodium benzoate administration; however, the patient died twelve days after admission. Since OTCD is not so rare and can be found in all ages, it should be considered fundamental for evaluation of hyperammoniemia. This case suggested that for a better prognosis of OTCD patients it is very important to prevent such an onset, and to make an as early as possible diagnosis and start to treatment.  相似文献   
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BACKGROUND: The objective of this study was to evaluate the clinical outcome after surgical management of renal cell carcinoma (RCC) extending to the inferior vena cava (IVC). METHODS: This study included a total of 55 patients (41 men and 14 women; mean age, 59.3 years) with RCC (39 right- and 16 left-sided tumors) involving the IVC, who underwent radical nephrectomy and tumor thrombectomy between 1983 and 2005 at a single institution in Japan. The level of thrombus was classified as follows: level I, infrahepatic; level II, intrahepatic; level III, suprahepatic; and level IV, extending to the atrium. Clinicopathological data from these patients were retrospectively reviewed to identify factors associated with survival. RESULTS: There were 11 and 18 patients who were diagnosed as having lymph node and distant metastases, respectively. Twenty-two patients had tumor thrombus in level I, 20 in level II, 10 in level III, and 3 in level IV. Pathological examinations demonstrated that 34 and 21 patients had clear cell carcinoma and non-clear cell carcinoma, respectively, 42, 9 and 4 were pT3b, pT3c and pT4, respectively, and 6, 35 and 14 were Grades 1, 2 and 3, respectively. Cancer-specific 1-, 3- and 5-year survival rates of these 55 patients were 74.5%, 51.4% and 30.3%, respectively. Among several factors examined, clinical stage (P = 0.047), lymph node metastasis (P = 0.016), histological subtype (P = 0.034) and tumor grade (P < 0.001) were significantly associated with cancer-specific survival by univariate analysis. Furthermore, multivariate analysis demonstrated clinical stage (P = 0.037) and tumor grade (P < 0.001) as independent predictors of cancer-specific survival irrespective of other significant factors identified by univariate analysis. CONCLUSIONS: In patients with RCC involving the IVC, biological aggressiveness characterized by tumor grade rather than tumor extension would have more potential prognostic importance; therefore, more intensive multimodal therapy should be considered in patients with high grade RCC with tumor thrombus extending into the IVC.  相似文献   
8.
BACKGROUND: The objective of this study was to evaluate the efficacy and safety of first-line high-dose chemotherapy (HDCT) combined with peripheral blood stem cell transplantation (PBSCT) for patients with advanced extragonadal germ cell tumors (EGGCT). METHODS: Six male patients with advanced non-seminomatous EGGCT were treated with HDCT combined with PBSCT following 2-3 cycles of conventional-dose induction chemotherapy. The regimens used for HDCT were carboplatin, etoposide and ifosfamide (ICE) in five patients and ICE plus paclitaxel (T-ICE) in one patient, and that for induction therapy was cisplatin, etoposide and bleomycin (PEB) in all patients. As a rule, HDCT was continuously administered until alpha-fetoprotein (AFP) and beta-human chorionic gonadotropin normalized (beta-HCG). RESULTS: Following 1-6 courses of HDCT (median, 4 courses), beta-HCG and AFP were normalized in all patients, and five and one patient were diagnosed as showing partial remission and stable disease, respectively. Five patients underwent surgical resection of residual tumors after HDCT, yielding necrotic tissue in two, mature teratoma in two, and viable cancer tissue in one, and the surgical margin was negative in all patients. At a median follow-up of 36 months, five patients were alive and disease-free, whereas the remaining one died of disease progression. Although all patients had grade 3 hematological toxicity, there was no treatment-related death by combining PBSCT. CONCLUSIONS: First-line HDCT with PBSCT could be safely administered to patients with advanced EGGCT, and the antitumor effect of this treatment was comparatively favorable. First-line HDCT therefore may represent an attractive option for patients with advanced EGGCT.  相似文献   
9.
OBJECTIVES: Lateral biopsies are thought to have a better cancer detection rate compared with standard sextant biopsies. This study aimed to determine whether lateral peripheral zone biopsies in Japanese men who underwent transrectal ultrasound-guided prostate biopsies provided a significantly higher cancer detection rate than sextant biopsies. METHODS: Between 1999 and 2004, data were collected from 461 men who underwent prostate biopsy and had enough data regarding the performance of lateral biopsies for statistical analysis. There were two categories in this study: (i) patients who underwent sextant prostate biopsies; and (ii) patients who underwent sextant biopsies plus lateral biopsies. RESULTS: Prostate cancer was detected in 141 (30.6%) of 461 patients. It was detected in 24 (22.2%) of 108 patients who underwent sextant biopsies and 117 (33.1%) of 353 patients who underwent sextant plus lateral biopsies. Lateral biopsies were not associated with a statistically higher rate of positive biopsy findings; however, we found a significantly higher ratio of patients with positive findings in those with prostate specific antigen (PSA) levels 10 ng/mL (one of 71, 1.4%) among those who had positive cores only in lateral biopsy samples (P < 0.0001). CONCLUSIONS: Lateral biopsies did not show a significantly higher detection ratio of prostate cancer compared to sextant biopsies. However, lateral biopsies were more effective than sextant biopsies in patients with lower PSA levels. Our findings might be useful for the establishment of biopsy strategies to detect prostate cancer, especially in patients with lower PSA levels.  相似文献   
10.

Background  

Nasal NK/T cell lymphoma is an aggressive disease and has a poor prognosis. Nasal NK/T cell lymphoma is refractory to conventional chemotherapy and has strong tendency of widespread relapse or dissemination into distant sites.  相似文献   
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