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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.
Allergic Predisposition Among Infants with Bronchiolitis   总被引:1,自引:0,他引:1  
Allergic predisposition among infants with bronchiolitis was examined. The number of infants with serum IgE exceeding mean +1 SD was 31/70 (44.3%). The rate of positive radioallergosorbent test (RAST) scores of 1 or more to mites, egg white, or milk was 31/71 (43.7%) and that of scores over 2 was 11/71 (15.5%). Eosinophils and/or mast cells were found in their nasal smears on several occasions. These results indicated that allergic predisposition may be observed among infants with bronchiolitis.  相似文献   
4.
A 67-year-old woman, who presented polyneuropathy, pleural effusion, ascites and sclerosing changes in the ribs, was admitted to our hospital on June 17, 1987. On admission, cerebrospinal examination showed a marked protein-cell dissociation and a delay in nerve conduction velocity. Bence-Jones protein was detected in urine, and the immunohistochemical study of biopsied bone marrow of the rib revealed lambda-chain positive plasmacytoma. Serum immunoelectrophoresis, however, showed no monoclonal gamma-globulinemia. From the findings described above, she was diagnosed as having Crow-Fukase syndrome associated with lambda-type light chain disease. Even with a therapy by prednisolone, platelet counts progressively declined to 10,000/ml3. Bone marrow aspiration showed normal number of megakaryocytes. Since platelet-associated IgG was increased to 452 ng/1.0 x 10(8) plt, a diagnosis of autoimmune thrombocytopenia was considered. Melphalan and cyclophosphamide to plasmacytoma resulted in a marked improvement of platelets. In addition, the level of platelet-associated IgG returned to normal range. Polyneuropathy, however, didn't respond to those therapies. It was suggested that both Crow-Fukase syndrome and thrombocytopenia were closely concerned with plasmacytoma but developed in a different manner.  相似文献   
5.
The anti-allergic activity of bryonolic acid (1) isolated from the cultured cells of Luffa cylindrica L. (Cucurbitaceae) was compared with that of glycyrrhetinic acid (2), the aglycone of glycyrrhizin from licorice. Compound 1, when administered to rats intraperitoneally at a dose of 600 mg/kg, inhibited homologous passive cutaneous anaphylaxis more strongly than 2 at the same dose. Compound 1 also significantly inhibited delayed hypersensitivity in mice which could not be inhibited by 2. In contrast to 2, 1 showed not only little toxicity but no visible side effects on mice, without impairing the activity of the hepatic enzyme (4,5 beta-dihydrocortisone:NADP+ delta 4-oxidoreductase) involved in steroid catabolism.  相似文献   
6.
The incidence of stonestreet formation after extracorporeal shock wave lithotripsy (ESWL) rises with increasing stone burden. However, stonestreet after ESWL is often experienced even in stones smaller than 20 mm. To examine whether the non-contrast helical computed tomography (CT) data could predict stonestreet formation in these stones, 53 radiopaque stones of 5-20 mm treated with ESWL were evaluated. Maximal dimension was measured on plain radiograph. From an attenuation value histogram graphed from the CT data, total stone volume and mean attenuation value were calculated. Seven stonestreets longer than 25 mm developed. There was no significant difference in maximal dimension and total stone volume between stones that did and stones that did not develop stonestreet. Mean attenuation value was the sole significant predictive factor. Application of mean attenuation value with cut-off level of 650 HU would anticipate stonestreet formation with a sensitivity of 85.7% and a specificity of 71.7%. The estimated risk of stonestreet formation is high in the treatment of stones with higher mean attenuation value.  相似文献   
7.
BACKGROUND: The precise mechanism of high altitude pulmonary oedema (HAPE) remains unclear. The purpose of this study was to evaluate the role of cytokines and P-selectin in the development of HAPE which occurred at moderate altitude in Japan. METHODS: The following cellular and biochemical markers and chemotactic cytokines were measured in the bronchoalveolar (BAL) fluid from four patients with HAPE at 2857-3180 m in the Japanese Alps: total proteins, albumin, lactate dehydrogenase (LDH), and interleukin (IL)-1 alpha, IL-1 beta, IL-1 receptor antagonist (ra), IL-6, IL-8, IL-10, tumour necrosis factor (TNF)-alpha, and the soluble form of P-selectin. RESULTS: At admission there were significant increases in the levels of total cells, especially macrophages and neutrophils, total protein, albumin and LDH when compared with 13 healthy individuals. Furthermore, the levels of IL-1 beta, IL-6, IL-8, and TNF-alpha were also considerably increased but returned quickly to the normal ranges or were not detected after recovery. The levels of IL-1 alpha, IL-10, and P-selectin did not change. CONCLUSIONS: These results suggest that an inflammatory process almost identical with acute respiratory distress syndrome (ARDS) may occur in HAPE, but that these changes are transient and are not associated with any increase in P-selectin levels in the BAL fluid.  相似文献   
8.
Effects of dual-action genistein derivatives on relaxation in rat aorta.   总被引:1,自引:0,他引:1  
Protein tyrosine kinases and nitric oxide (NO) play important roles in several cardiovascular diseases. In this study, we examined the actions of two compounds, each has structure of genistein (a tyrosine kinase inhibitor) and an NO donor, on endothelium-independent relaxation responses in the isolated rat aorta. By rational drug design, genistein was modified to acquire an NO donor, and we synthesized two such compounds (G-II, G-VI). These compounds and genistein induced dose-dependent relaxation responses in endothelium-denuded aortic strips, the rank order of potencies being G-VI > G-II > genistein. Incubation of endothelium-denuded strips with 1H-[1,2,4] oxadiazolo[4,3-a]-quinoxalin-1-one (ODQ, 10 microM), a guanylyl cyclase inhibitor, inhibited both the G-II- and G-VI-induced relaxations, but not the genistein-induced relaxation. The residual relaxations induced by these two compounds were similar to the genistein-induced relaxation. Incubation of endothelium-denuded strips with lysophosphatidylcholine (LPC, 20 microM)-which is a major atherogenic lysophospholipid component of oxidized low-density lipoprotein and is known to activate tyrosine kinase-caused a significant rightward shift in the dose-response curve for genistein. LPC also shifted the G-II- and G-VI-induced relaxation curves to the right; however, these relaxations in the presence of LPC were greater than that induced by genistein. The sodium nitroprusside-induced relaxation in endothelium-denuded strips was similar between in the absence and presence of LPC. These results suggest that each of our newly developed G-II and G-VI compounds has a dual action, as an NO donor and a tyrosine kinase inhibitor. These compounds may be useful against certain cardiovascular diseases.  相似文献   
9.
A 52-year-old woman had a newly recognized disorder of familial hypoceruloplasminemia, blepharospasm, retinal degeneration, and high-density areas in CT of the basal ganglia and liver scan. Immunofixation electrophoresis disclosed apoceruloplasmin deficiency. Kinetic, x-ray analysis, and histochemical study showed accumulation of iron in liver and brain, but not of copper. Intestinal copper absorption was reduced, but liver uptake was increased. Ceruloplasmin is involved in iron metabolism, and the findings suggest that hypoceruloplasminemia due to lack of apoceruloplasmin was causally linked to the iron deposition in basal ganglia and other organs, leading to blepharospasm and retinal degeneration.  相似文献   
10.
Community-acquired pneumonia is one of the major respiratory diseases causing hospital admission in previously healthy patients. Prompt and appropriate antibiotic selection is essential for recovery. The authors tried to determine the distribution of the etiologic agents of community-acquired pneumonias and to analyze predictive factors. Out of 188 cases of community-acquired pneumonia presenting to our hospital, etiologic agents were determined in 106 cases (56%). Twenty-nine cases were due to Streptococcus pneumoniae, 27 cases due to Mycoplasma, 17 cases due to Haemophilus influenzae and 21 cases due to Mycobacterium tuberculosis. M. tuberculosis was the cause in 11% of all cases and the importance of pulmonary tuberculosis must be emphasized as a community-acquired pneumonia. Out of 58 cases under 50 years old, Mycoplasma pneumoniae was the etiologic agent in 23 cases (40%) and S. pneumoniae in 7 cases (12%). Out of 62 cases not less than 70 years old. M. tuberculosis was the most common etiologic agent (15 cases, 24%). S. pneumoniae followed, being causative in 13 cases (21%). M. tuberculosis was the cause in 10 cases out of 31 cases who did not complain of fever at presentation. In 86 cases who did not show leukocytosis on admission, 21 cases were due to Mycoplasma (24%) and 15 cases were due to M. tuberculosis (17%). In particular 17 cases were due to Mycoplasma among 28 cases under 50 years old without leukocytosis (61%), and 11 cases were due to M. tuberculosis in the 27 cases no less than 70 years old without leukocytosis (41%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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