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1.
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   
2.
Aminoglycosides are widely used, and clinicians continue to seek newer and better methods for initial dosing of these agents. Recently, three new methods were introduced: Thomson, Reesor Nimmo, and dosing in Tenopathy by easy-to-use multipliers (DREM). In comparing them with older, traditional dosing methods in patients with various degrees of renal function, the pharmacokinetic variables of gentamicin were determined from steady-state peak (Cmax) and trough (Cmin) serum concentrations using individualized regimens in 88 patients. Dosages were determined in each patient using the method of Hull-Sarubbi, rule of eights, and the three new methods, and the resultant Cmax and Cmin values were calculated from dosages generated by each method. The daily doses and Cmax values derived with the Hull-Sarubbi, Thomson, and Reesor Nimmo methods were not significantly different (p>0.05). The Hull-Sarubbi was the most precise (root mean squared prediction error 1.3) and least biased (mean prediction error −0.05) of the five methods in predicting target gentamicin serum peak concentrations (Cmax 6.5 mg/L). The Hull-Sarubbi (69%), Thomson (86%), and Reesor Nimmo (70%) methods yielded therapeutic Cmax (5–8 mg/L) in a significantly higher percentage of patients than did the rule of eights (32%) and DREM (35%), (p<0.05). Therefore, if gentamicin serum concentrations are not available, the first three appear to be reasonable methods for initiating gentamicin dosage regimens, but the last two may not be desirable to use in a clinical setting. These conclusions are based on the assumption that patients are adults with stable renal function and relatively stable clinical conditions.  相似文献   
3.
During the course of our studies on dental caries prevention by traditional medicines, fatty acids (myristic and oleic acids etc.) and procyanidins from betel nuts (the seed of Areca catechu L.) were respectively revealed to be the major antibacterial principles against a primary cariogenic bacterium, Streptococcus mutans, and the major inhibitory principles against glucosyltransferase from S. mutans.  相似文献   
4.
Between November 1986 and April 1989, 101 patients with superficial bladder cancer were treated with intravesical instillations of mitomycin C on day 1 and doxorubicin on day 2 of each week for 5 consecutive weeks. Of 61 complete responders, 23 patients with carcinoma in situ and 28 with papillary cancer were randomly assigned to a non-maintenance group or to a group receiving maintenance therapy consisting of monthly instillations of the same drugs for 12 months. The 2-year non-recurrence rate calculated for patients with carcinoma in situ was significantly better in the maintenance group than in the non-maintenance group. A similar tendency was observed for patients with papillary cancer, although the difference was not significant. Side effects were considerable, with moderate to severe bladder irritation occurring in approximately half of the patients. In addition to our previous findings, the present results indicate that this intravesical combination chemotherapy is effective in eliminating superficial bladder cancers and that since the effect is not durable, even in complete responders, maintenance therapy is necessary to reduce subsequent tumor recurrence.Presented at the 4th International Conference on Treatment of Urinary Tract Tumors with Adriamycin/Farmorubicin, 16–17 November 1990, Osaka, Japan  相似文献   
5.
The polypeptide compositions and antigenic components of Rickettsia tsutsugamushi were analyzed by modifying the solubilization conditions prior to polyacrylamide gel electrophoresis and by using monoclonal antibodies in immunoblotting experiments. Several polypeptides were converted to larger or smaller molecules by using various conditions for rickettsial sample preparation. Solubilization of a sample in 2-mercaptoethanol-containing buffer resulted in conversion of high-molecular-weight polypeptides to smaller polypeptides and conversion of some of the 43-kilodalton (43K) polypeptide to a 46K polypeptide. The heat modifiability of selected polypeptides was shown by heating samples at 100 degrees C. A major polypeptide on the rickettsial surface which showed strain-specific antigenicity appeared at the 43K position in samples solubilized at 37 degrees C but moved to the 56K position after samples were heated at 100 degrees C. Immunoblotting with an anti-56K polypeptide monoclonal antibody demonstrated that the reactive antigens existed predominantly as the higher-molecular-weight polypeptides. These polypeptides were converted to 43K polypeptides at 37 degrees C or the 56K polypeptides at 100 degrees C by cleavage of disulfide linkages with 2-mercaptoethanol treatment.  相似文献   
6.
7.
Electrogastrograms (EGGs) were recorded in patients both before and after receiving proximal gastrectomy plus jejunal interposition (PGJI) or just after receiving total gastrectomy plus jejunal interposition (TGJI). Intraluminal pressure was also recorded in some postoperative patients. The EGG 3 cpm component (2.5-4.9 cpm) remained after PGJI, but subsequently decreased with a significant reduction in the preoperative to postoperative ratio of the 3 cpm components (P<0.05). The mean frequency of the 3 cpm components increased significantly after PGJI (P<0.05) and its instability factor increased. The EGG 10 cpm components became relatively dominant compared to other frequency components in 2 out of 8 of patients having PGJI but the mean amplitude of 10 cpm decreased. In TGJI patients, only the 10 cpm component was conspicuous in EGG as in the case of total gastrectomy and Roux en Y anastomosis procedures. The spectral frequencies of intraluminal pressure in the interposed jejunum were similar to the EGG of 10 cpm components both in the case of PGJI and TGJI patients. In conclusion, surface EGG could record the electrical activities of the interposed jejunum more easily in patients having had TGJI than in PGJI.  相似文献   
8.
The inhibitory effects of glycoproteins separated from a hot water extract of corn silk (U-CSE) on the formation of IgE antibodies after primarily and secondarily challenged responses with dinitrophenyl (DNP)-ovalbumin (OVA) antigen in mice were investigated using the passive cutaneous anaphylaxis (PCA) test. When U-CSE was given intranasally or intraperitoneally the day before primary immunization, IgE antibody production was strongly inhibited. Furthermore, it was found that new formation of IgE antibodies was readily inhibited by U-CSE administration in mice with high levels of IgE after primary immunization. It was also found that U-CSE markedly suppressed IgE antibody formation in secondarily challenged responses with the antigen. U-CSE may be clinically applicable to type I allergic diseases.  相似文献   
9.
Background Cat cry syndrome is an autosomal disease accompanying abnormal deletion of chromosome 5 and occurs in only 1 of 50,000 neonates. Scoliosis has been reported as a skeletal complication in cat cry syndrome. The characteristics and causes of scoliosis in this rare syndrome are unknown. The purpose of this study was to present the characteristics of scoliosis in cat cry syndrome and to speculate on its causative mechanisms. Methods We report on 11 cases (5 boys and 6 girls) of cat cry syndrome. Detailed investigations of scoliosis, as well as physical and imaging examinations, were performed to characterize scoliosis and its causes. Average age at initial diagnosis of scoliosis was 4.3 years, and average age at final examination was 11.8 years. Results The incidence of scoliosis was as high as 73% (8/11). Most cases show a single right thoracic curve. Of the 8 patients with scoliosis, 3 patients who had increased muscular tone showed marked progression of scoliosis with growth. Conclusions Muscular hypertonia may play a key role in the progression of scoliosis in cat cry syndrome.  相似文献   
10.
We report herein the cases of two infants who developed right pneumonectomy syndrome, both of whom were born with gross C-type esophageal atresia (EA/TEF), and a hypoplastic right lung arising from the lower esophagus, being a bronchopulmonary foregut malformation (BPFM). Appropriate and well-timed treatments for a variety of sequelae primarily caused by the mediastinal shift must be considered after right pneumonectomy in early childhood.  相似文献   
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