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41.

The effects of the water extract of Sinomeni Caulis et Rhizoma (SCR-WE) and its major constituents, sinomenine (SIN) and magnoflorine (MAG), on moderate hemolysis induced by lysophosphatidylcholine (LPC) were investigated in rat erythrocytes and compared with the anti-hemolytic effects of lidocaine (LID) and propranolol (PRO) as reference drugs. LPC caused hemolysis at concentrations above the critical micelle concentration (CMC), and the concentration of LPC producing moderate hemolysis (60 %) was approximately 10 μM. SCR-WE at 1 ng/mL–100 μg/mL significantly inhibited the hemolysis induced by LPC. SIN and MAG attenuated LPC-induced hemolysis in a concentration-dependent manner from very low to high concentrations (1 nM–100 μM and 10 nM–100 μM, respectively). In contrast, the inhibiting effects of LID and PRO on LPC-induced hemolysis were observed at higher concentrations (1–100 μM) but not at lower concentrations (1–100 nM). Neither SIN nor MAG affected micelle formation of LPC, nor, at concentrations of 1 nM–1 μM, did they attenuate the hemolysis induced by osmotic imbalance (hypotonic hemolysis). Similarly, SCR-WE also did not modify micelle formation or hypotonic hemolysis, except at the highest concentration. These results suggest that SIN and MAG potently protect the erythrocyte membrane from LPC-induced damage and contribute to the beneficial action of SCR-WE. The protective effects of SIN and MAG are mediated by some mechanism other than prevention of micelle formation or protection of the erythrocyte membrane against osmotic imbalance.

  相似文献   
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Although side-to-side isoperistaltic anastomosis is a useful strictureplasty technique when long segments of intestinal stenosis complicate Crohns disease, concerns have been raised regarding disease recurrence adjacent to the anastomosis. We performed side-to-side isoperistaltic anastomosis without spatulated intestinal ends as a method of reconstruction after intestinal resection for Crohns disease; both intestinal ends were transversely closed like a Heineke-Mikulicz-type strictureplasty. With this procedure, the luminal diameter proximal and distal to the anastomosis became wider than the original diameter of the intestine. This new procedure, which we refer to as the modified side-to-side isoperistaltic anastomosis with double Heineke-Mikulicz procedure could become an alternative operation after intestinal resection in persons with Crohns disease, although long-term outcome analysis is necessary.  相似文献   
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Nonenzymatic glycosylation of plasma proteins may contribute to the excess risk of developing atherosclerosis in patients with diabetes mellitus. Although it is believed that high-density lipoprotein (HDL) is glycosylated at an increased level in diabetic individuals, little is known about a possible linkage between glycated HDL and endothelial dysfunction in diabetes. To clarify whether glucose-modified HDL affects the function of endothelial cells, we first examined herein the level of H(2)O(2) generation from cultured human aortic endothelial cells (HAECs) exposed to a glycated oxidized HDL (gly-ox-HDL) prepared in vitro. Incubation for 48 hours with 100 microg/mL of gly-ox-HDL induced significant release of H(2)O(2) from cells and gly-ox-HDL-induced H(2)O(2) formation was inhibited in the presence of diphenyleneiodonium, an inhibitor of NADPH oxidase. In addition, stimulation of HAECs with gly-ox-HDL for 48 hours elicited a marked downregulation of catalase and Cu(2+), Zn(2+)-superoxide dismutase (CuZn-SOD), suggesting H(2)O(2) formation by gly-ox-HDL to be due to a disturbance involving oxidant and antioxidant enzymes in the cells. Treatment of HAECs with gly-ox-HDL attenuated the expression of endothelial nitric oxide synthase (eNOS), but not inducible nitric oxide synthase (iNOS), and this was followed by decreased production of nitric oxide (NO) by the cells. Furthermore, in vitro experiments with glycated HDL (gly-HDL) in the presence of 2 mmol/L EDTA and Cu(2+)-oxidized HDL suggested the effect of gly-HDL on endothelial function to be possibly potentiated by additional oxidative modification. Taking all of the above findings together, gly-ox-HDL may lead to the deterioration of vascular function through altered production of reactive oxygen species and reactive nitrogen species in endothelial cells.  相似文献   
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Objectives:   Macrophages (Mφs) have various functions and play a critical role in host defense and the maintenance of homeostasis. Mφs exist in every tissue in the body, but Mφs from different tissues exhibit a wide range of phenotypes with regard to their morphology, cell surface antigen expression and function, and are called by different names. However, the precise mechanism of the generation of macrophage heterogeneity is not known. In the present study, the authors examined the functional heterogeneity of Mφs generated from human monocytes under the influence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and macrophage-CSF (M-CSF).
Methodology:   CD14 positive human monocytes (Mos) were incubated with M-CSF and GM-CSF for 6–7 days to stimulate the generation of M-CSF-induced monocyte-derived Mφs (M-Mφs) and GM-CSF-induced monocyte-derived Mφs (GM-Mφs), respectively. The expression of cell surface antigens and several functions such as antigen presenting cell activity, susceptibility to oxidant stress, and the susceptibility to HIV-1 and mycobacterium tuberculosis infection were examined.
Results:   GM-Mφs and M-Mφs are distinct in their morphology, cell surface antigen expression, and functions examined. The phenotype of GM-Mφs closely resembles that of human Alveolar-Mφs (A-Mφs), indicating that CSF-induced human monocyte-derived Mφs are useful to clarify the molecular mechanism of heterogeneity of human Mφs, and GM-Mφs will become a model of human A-Mφs.  相似文献   
46.
Staphylococcus aureus is a leading cause of ventricular assist device-related infections. This study evaluated the protective effect against S. aureus infection of active and passive immunization that targeted 3 proteins involved in bacterial attachment to a murine intra-aortic polyurethane patch. Active immunization of mice with a combination of the A domains of clumping factor A (ClfA), fibronectin-binding protein A (FnBPA) and fibronectin-binding protein B or passive immunization with monoclonal antibodies against ClfA and FnBPA resulted in a higher level of protection than that obtained by vaccination with either protein or antibody alone. The combination of antibodies or protein antigens appears to provide enhanced protection against prosthetic-device infection.  相似文献   
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