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Off-pump coronary artery bypass grafting (OPCABG) has recently gained popularity. During OPCABG, patients remain vulnerable to ischemic-reperfusion injury due to a temporary coronary occlusion without any active cardioprotection. Some strategies such as ischemic preconditioning (IP) and an intracoronary shunt have been applied with a view to minimizing the effects of ischemia, but the effects of these strategies remain controversial. This study was carried out to investigate the protective effect of lidocaine against myocardial ischemic-reperfusion injury. Twenty-one pigs were assigned to three groups, each consisting of seven pigs. In the control group, using a left internal thoracic artery (LITA) bypass circuit, the left anterior descending coronary artery (LAD) was occluded for 45 min followed by two hours of reperfusion. In the IP group, five min of occlusion followed by 15 min of reperfusion was performed. In the lidocaine group, 2 mg/kg of lidocaine was administered directly into the LAD just before the LAD occlusion. Infarct size expressed as a percentage of the area at risk was significantly smaller in the lidocaine group (2.7+/-4.2%) than in the control group (79.9+/-6.0%, p<0.001) or the IP group (57.0+/-25.9%, p<0.001). Lidocaine exhibited a potent myocardial protective effect in the present OPCABG model.  相似文献   
3.
We cultivated kidney hematopoietic cells from clonal triploid ginbuna crucian carp, Carassius auratus langsdorfii. Proliferating cells from hematopoietic cell cultures were harvested and injected into tetraploid hybrids (clonal triploid ginbuna and goldfish hybrid) which possess three sets of chromosomes from a triploid clone and a haploid set of chromosomes from goldfish (Carassius auratus). After injection of cultured triploid cells (donor cells), blood samples were obtained from tetraploid hybrids (recipients) every other week. Blood cells stained with acridine orange were measured by flow cytometry to trace the injected donor cells by means of differences in DNA content. Although erythrocytes were not produced in donor cell cultures, such cultures maintained precursor cells capable of differentiation into erythrocytes in vivo. After 4-12 weeks of transplantation, mature erythrocytes derived from the donors were observed in the blood circulation of the recipient fish. These results indicated that the ginbuna hematopoietic cell culture system is an in vivo situation suitable for the study of hematopoietic control mechanisms.  相似文献   
4.
Amyloid enhancing factor (AEF) was extracted from spleens of mice that had received amyloidogenic stimulation. Sephacryl S 300 gel filtration of the crude AEF yielded five fractions, among which strong AEF activity was present in the first peak (Fl), and confirmed by an amyloid induction experiment. An anti AEF antiserum was obtained from a rabbit by immunization with Fl. This antibody reacted strongly with splenic polymorphonuclear leukocytes (PML) from mice given amyloidogenic stimulation, and weakly with those from normal untreated mice. Isoelectric focusing (IEF) analysis of both Fl and sera from mice given amyloidogenic stimulation was performed. A single band was observed on IEF analysis of Fl, whereas many bands were seen on IEF analysis of the sera. After the substances in the gel had been transferred to nitrocellulose membranes by capillary blotting, the membranes were made to react with the anti-AEF antiserum. The results suggested that AEF is a high molecular-weight substance derived from PML and increases in the serum at the time of, or shortly prior to, amyloid deposition in the spleen. Acta Pathol Jpn 39: 349∼355, 1989.  相似文献   
5.
Amyloid depositions of pancreatic islets were investigated with electron microscopy in a case of type III glycogenosis.

Beta cells adjoining small amyloid depositions were shown to have cytoplasmic invaginations where closely packed amyloid fibrils were disclosed regularly orientated amyloid bundles. In the cytoplasm of the beta cells, some membrane-bounded vesicles contained amyloid fibrils and a few beta granules directly transformed into the fibrils within the vesicles.

These findings indicate that, at least in this case, the beta cells play a crucial role in the formation of insular amyloid.  相似文献   
6.
Addition of various heparinoids to the lactose-introduced, water-soluble chitosan (CH-LA) aqueous solution produces an injectable chitosan/heparinoid hydrogel. In the present work, we examined the capability of the chitosan/non-anticoagulant heparin (periodate-oxidized (IO(4)-) heparin) hydrogel to immobilize fibroblast growth factor (FGF)-2, as well as the controlled release of FGF-2 molecules from the hydrogel in vitro and in vivo. The hydrogel was biodegraded in about 20 days after subcutaneous injection into the back of a mouse. When the FGF-2-incorporated hydrogel was subcutaneously injected into the back of both mice and rats, a significant neovascularization and fibrous tissue formation were induced near the injected site. These results indicate that the controlled release of biologically active FGF-2 molecules is caused by biodegradation of the hydrogel, and that subsequent induction of the vascularization occurs.  相似文献   
7.
Osteopontin (OPN) plays a pivotal role in various immune responses and inflammatory diseases. OPN is expressed in various granulomatous diseases; however, the cellular and molecular role of OPN in these diseases is not well known. We analyzed the role of OPN in a beta-glucan-induced hepatic granuloma model. First, we found that neither OPN deficiency nor overexpression of OPN affected the number and the size of hepatic granulomas at day 7, indicating that OPN is not involved in the formation of hepatic granulomas at the early stages. Importantly, OPN did not influence the liver tissue damage as defined by alanine aminotransferase and aspartate aminotransferase levels at early stages. Second, OPN deficiency resulted in the reduction of IL-12 and IFN-gamma production at early stages. Third, at late stages, OPN deficiency resulted in a decrease in the number and size of hepatic granulomas, and a reduction of liver tissue injury. This was due to the reduction of the cellular recruitment including macrophages, CD4 T cells and dendritic cells into the liver, and the reduction of tumor necrosis factor (TNF)-alpha production in the liver. In contrast, overexpression of OPN resulted in the persistence of granuloma formation. These data suggest that OPN affects the persistence of hepatic granuloma formation. Our results indicate that OPN up-regulates the production of IL-12 and IFN-gamma within the granulomas at early stages, and OPN has an additional role in the regulation of cellular recruitment and TNF-alpha production at late stages that determine the severity of liver tissue injury.  相似文献   
8.
A clone of NIH3T3 transformant (H3) can yield subcutaneous tumors and experimental pulmonary metastasis in nude mice. Compared to H3 in culture, the cells after in vivo tumor growth (H3-N) acquired enhanced tumorigenicity and metastatic ability. Also, indirect immunofluorescence revealed that cellular fibronectin (c-FN) of H3-N was decreased remarkably. We have studied the interactions between H3 and extracellular matrices to elucidate these phenomena. In the present study, we observed the effect of NIH3T3, H3, and H3-N cultured in type I collagen gel. Morphologically in the collagen gel, NIH3T3 assumed an extensive elongated fiber-like shape, H3 assumed a moderately elongated shape, and H3-N assumed a round or spindle shape with short pseudopodia. Compared to conventional cultures on dishes, cell proliferation of all three types was suppressed in collagen gel, but the degree of the suppression was least in H3-N. As a result, H3-N grew fastest in collagen gel. The variants which acquired growth advantage in the subcutaneum of mice also kept it in collagen gel. H3 cells were cultured in type I collagen gel for 4 weeks, a period comparable to that of tumor formation in nude mice. The cells after this long-term culture (H3-C) acquired enhanced tumorigenicity and metastatic ability nearly equal to that of H3-N. FACS analysis revealed that the c-FN of H3-C had decreased to a value comparable to that of H3-N. This means that type I collagen gel as well as subcutaneous tissues could select variants of H3 with less c-FN through proliferation. Moreover, it is suspected that lattices of type I collagen regulate cell proliferation of fibroblast via c-FN. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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Combined small cell and non-small cell carcinoma is relatively rare in the lung. Examination of the clonal relationship of different components in this type of tumor may give a clue to the rarity. We retrieved 6 such tumors; all 6 had small cell carcinoma and adenocarcinoma components, and 3 had an additional squamous cell carcinoma component. We examined the point mutations in the p53 gene and allelic loss (ie, the loss of heterozygosity [LOH] pattern) of chromosome 3p in each component. p53 mutations were detected in the small cell carcinoma component of 5 tumors and in the non-small cell carcinoma components of 2 tumors. In 1 case, the squamous cell carcinoma component had a p53 mutation locus identical to that in the small cell carcinoma component, but in the other case, the adenocarcinoma component had a different mutation than that in the small cell carcinoma component. Chromosome 3p LOH loci in the squamous cell carcinoma component were present in the small cell carcinoma component in all 3 cases, but some LOH loci were not identical in the small cell carcinoma and adenocarcinoma components in 3 cases. These results suggest that the small cell and squamous cell carcinoma components of combined small cell lung carcinomas have an intimate clonal relationship. On the other hand, the adenocarcinoma component often may be derived from a separate clone or, more likely, undergo a progressive process separate from the squamous cell-small cell carcinoma beginning in a very early stage, that is, before the appearance of p53 and chromosome 3p abnormalities. This tumorigenesis process may explain the relative rarity of combined small cell and non-small cell carcinoma, which occurs primarily in the peripheral lung, an infrequent site of squamous cell carcinoma.  相似文献   
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