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71.
Phorbol myristate acetate (PMA)-induced superoxide radical (O(2)(-))-production in guinea pig peritoneal polymorphonuclear leukocytes (PMNs) was significantly lower than that in peripheral cells. To determine the role of phosphotyrosine proteins in the lower O(2)(-) production, the effect of ST638 and genistein, tyrosine kinase inhibitors, on PMA-induced O(2)(-) production in peritoneal PMNs was examined. PMA-induced O(2)(-)-production of the cells was increased by the pretreatment with ST638 or genistein, the increment depending on the inhibitor concentration. The p47phox level in the plasma membrane of PMA-stimulated PMNs was increased by the pretreatment with ST638, although the phosphorylated p47phox level in the cells was not altered by ST638. On the other hand, PMA-induced O(2)(-)-production of peripheral PMNs was not affected by the pretreatment with ST638, but that of cytochalasin B (CB)-primed peripheral PMNs significantly increased by further treatment with ST638. The phosphotyrosine protein level of peritoneal PMNs was higher than that of the peripheral cells, especially in cytosolic proteins including 50-60 and 70-85 kDa proteins, and that of the CB-primed peripheral cells was also higher than that of the intact cells in similar cytosolic proteins to those above. Further treatment of CB-primed peripheral cells with ST638 resulted in a lower level of phosphotyrosine proteins. These findings suggest that phosphorylation of some protein(s) at specific tyrosine residues inhibits the translocation of p47phox to the plasma membrane from the cytosol, resulting in lower O(2)(-)-generation in casein-induced peritoneal exudate PMNs.  相似文献   
72.
OBJECTIVES: A minilaparotomy approach (skin incision less than 7 cm) to resection of colon cancer is technically feasible, but objective data supporting its benefit are scarce. The aim of this study was to clarify whether minilaparotomy is independently associated with a reduction in the acute inflammatory response after resection of colorectal cancer. DESIGN: Thirty-one patients who underwent surgical resection of colorectal cancer using minilaparotomy or conventional laparotomy were included in this nonrandomized prospective study. Inflammatory responses were evaluated with serum interleukin-6 (IL-6) and C-reactive protein (CRP) levels. RESULTS: In both the minilaparotomy and conventional laparotomy groups, serum IL-6 and CRP levels significantly increased 24 h after the operation (1POD) compared to preoperative levels (p < 0.0001 and p < 0.0001, respectively). Median serum levels of IL-6 and CRP in the minilaparotomy group were significantly lower at 1POD versus the conventional group (p = 0.0066 and p = 0.0033, respectively). Multivariate analyses showed that a smaller increase in serum IL-6 or CRP levels at 1POD [less than 75th percentile (112.9 or 10.6 mg/ml, respectively)] was independently related to only minilaparotomy. CONCLUSIONS: These data in this nonrandomized trial suggest that minilaparotomy may be independently associated with reduced inflammatory responses in colorectal cancer resection.  相似文献   
73.
PURPOSE: The purpose of this study was to clarify whether or not preoperative serum levels of interleukin-6 (IL-6) correlate with well-established prognostic variables (serum level of carcinoembryonic antigen (CEA), stage, histological grade, lymphatic and venous invasion) in colorectal cancer patients. PATIENTS AND METHODS: Serum levels of IL-6 and CEA were determined in 62 patients who underwent resection of colorectal cancer. The patients were divided into two groups based on a selected cut-off value: high and low IL-6 and CEA groups. RESULTS: The median serum level of IL-6 in colorectal cancer patients was significantly higher than the median level in normal controls (p = 0.0014). Multivariate logistic regression analysis showed that a high serum level of CEA is an independent predictor for a high serum level of IL-6 (odds ratio, 4.10; p = 0.046). CONCLUSION: A high serum level of IL-6 is significantly associated with a high serum level of CEA in preoperative colorectal cancer patients.  相似文献   
74.
PURPOSE: We evaluated the contribution of a nucleoside transporter (NT) consisting of an equilibrative NT (ENT) and a concentrative Na(+)/nucleoside cotransporter (CNT) to the uptake of THP and DOX by mouse Ehrlich ascites carcinoma cells. METHODS. Transport experiments were performed using a silicone layer method. The expression of CNT isoforms was confirmed by RT-PCR analysis. RESULTS: The effects of inhibition of the ENT inhibitors, nitrobenzylthioinosine (NBMPR) and nitrobenzylthioguanosine, on THP and DOX uptake by Ehrlich cells was negligible. THP uptake, but not DOX uptake, partially depended on an inwardly directed Na(+) gradient, and the uptake was inhibited by all the inhibitors of CNT examined. Furthermore, efflux of [(3)H]uridine from Ehrlich cells was stimulated by the addition of THP to the extracellular compartment, which was definitive evidence of CNT-mediated uptake of THP. The mRNA for CNT2, but not that for CNT3, was detected in Ehrlich cells, which is consistent with the characteristics of [(3)H]uridine uptake. In the cells, formycin B, a representative CNT2 ligand, had cis-inhibitory and trans-stimulatory effects on THP uptake. CONCLUSION: These results demonstrate that THP, but not DOX, is taken up into Ehrlich cells partially via a uridine-transportable CNT.  相似文献   
75.
PURPOSE: This study examined whether a short-term physical or mental training reduces the physiological load and perceived exertion of the in-clothes swimming. METHODS: The study included 24 male inter-collegiate competitive swimmers with no previous experience of the in-clothes swimming. Prior to the training, the subjects performed 200-meter swimming with two styles of swimming, namely the crawl and elementary backstroke, and the degree of perceived exertion in the Borg scale, heart rate, and blood lactic acid level were determined. Following this baseline determination, the subjects were divided into 4 groups with 6 individuals each. These four groups were Group A "in-clothes training", Group B "image training", Group C "swimsuit training", and Group N "no training". Group A and C were lectured on the in-clothes swimming and practiced 7.5 min-long in-clothes swimming per day for a week with the two swimming styles, with Group A subjects wearing daily clothes and Group C subjects in swimsuits. Group B received 15 min of nonphysical mental practice primarily through viewing video recording of swimming performance everyday for a week. No training was given to Group N. At the completion of the training session, the subjects underwent the 2nd 200-meter swimming, and the physiological parameters were determined. RESULTS: The 1st in-clothes swimming load test showed that the elementary backstroke swimming resulted in significantly lower values of heart rate, blood lactic acid level, and perceived exertion than the crawl. For Group N, no difference was observed in the physiological parameters between the 1st and 2nd load test with either the elementary backstroke or crawl. Upon the 2nd in-clothes load test with the elementary backstroke, all three parameters were lower for Group A, B, and C than those seen for the 1st load test, and these differences were statistically significant, except for blood lactic acid in Group A. The 2nd in-clothes load test with the crawl showed that both heart rate and blood lactic acid were lower than those of the 1st load test for all three groups, with the differences in heart rate and blood lactic acid in Group A and that in blood lactic acid in Group B reaching the statistic significance. With respect to perceived exertion, the Borg score determined after the in-clothes load test with the crawl was significantly reduced for Group A, B, and C. The score after the in-clothes load test with the elementary backstroke was significantly reduced only for Group A. CONCLUSION: The elementary backstroke, when practiced in-clothes, imposes a relatively less physiological load. The present training methods can reduce physiological load and/or perceived exertion of the in-clothes swimming. Thus, both image training and swimsuit swimming are equally effective as a training method of the in-clothes swimming.  相似文献   
76.
BACKGROUND: Angiotensin II (Ang II), which contracts vascular smooth muscle cells (VSMCs), has been reported to regulate VSMC growth. Recently formed transgenic mice without angiotensinogen or Ang II receptors showed vascular alterations. However, it is still unclear how their VSMCs alter. We explored the role of Ang II via the Ang II type 1a receptor (AT1a) in VSMCs in vivo using AT1a null mutant mice. METHODS: We analyzed the ultrastructure of the intrarenal arteries in AT1a null mutant mice that were homozygous for a targeted disruption of AT1a receptor gene using light and electron microscopy. RESULTS: The structural changes of the intrarenal arteries in AT1a null mutant mice showed the wall thickening, which in the interlobar, arcuate, and proximal interlobular arteries consisted of two additional populations of VSMCs, on the luminal and abluminal sides of the media. The luminal overpopulation of smooth muscle cells (SMCs) was arranged in a longitudinal direction separated by increased interposed elastic laminae. The abluminal overpopulation of SMCs ran in circumferential directions separated from the main population. The cytological structure of VSMCs in AT1a null mutant mice was smaller in size, contained more organelles for protein synthesis and secretion than in control mice, and had poorly developed contractile apparatus. CONCLUSIONS: The lack of AT1a signaling causes structural abnormalities in the renal vascular system and transforms the phenotype of VSMCs into cell proliferation, induces the escape of VSMCs from the circular mechanical integrity, and results in increased synthesis of extracellular matrices.  相似文献   
77.

Background

Although electronic health record systems (EHRs) and emergency department information systems (EDISs) enable safe, efficient, and high-quality care, these systems have not yet been studied well. Here, we assessed (1) the prevalence of EHRs and EDISs, (2) changes in efficiency in emergency medical practices after introducing EHR and EDIS, and (3) barriers to and expectations from the EHR-EDIS transition in EDs of medical facilities with EHRs in Japan.

Materials and methods

A survey regarding EHR (basic or comprehensive) and EDIS implementation was mailed to 466 hospitals. We examined the efficiency after EHR implementation and perceived barriers and expectations regarding the use of EDIS with existing EHRs. The survey was completed anonymously.

Results

Totally, 215 hospitals completed the survey (response rate, 46.1%), of which, 76.3% had basic EHRs, 4.2% had comprehensive EHRs, and 1.9% had EDISs. After introducing EHRs and EDISs, a reduction in the time required to access previous patient information and share patient information was noted, but no change was observed in the time required to produce medical records and the overall time for each medical care. For hospitals with EHRs, the most commonly cited barriers to EDIS implementation were inadequate funding for adoption and maintenance and potential adverse effects on workflow. The most desired function in the EHR-EDIS transition was establishing appropriate clinical guidelines for residents within their system.

Conclusion

To attract EDs to EDIS from EHR, systems focusing on decreasing the time required to produce medical records and establishing appropriate clinical guidelines for residents are required.  相似文献   
78.
We attempted to detect the bcr-abl fusion gene and ras gene family in CML by the in vitro focus forming assay and the tumorigenicity assay. Eight of 14 chronic phase and both of two blastic phase cases showed transforming activity in the tumorigenicity assay. However, only one chronic phase sample was positive in the in vitro focus forming assay. Among these 10 transformants, we found N-ras activation in one chronic phase, and K-ras activation in another chronic phase case. The bcr-abl fusion gene was activated in one chronic phase and all of the blastic phase cases by the tumorigenicity assay. The present result showed that the bcr-abl fusion gene transfected N1H3T3 cells formed tumors in nude mice in contrast to the in vitro focus forming assay. The bcr-abl fusion gene may play important roles in the progression as well as the pathogenesis of CML.  相似文献   
79.
80.
Human epidermal keratinocytes, immortalized by the introduction of SV40-adenovirus recombinants (9), were maintained in a low calcium (0.15 mM) defined medium. When differentiation was induced by a higher extracellular calcium concentration (1.5 mM), these cells altered in shape and developed stratification with formation of desmosomes, while they demonstrated limited terminal keratinization. The expression of involucrin, one of the precursor proteins of the cornified envelope, became elevated as the cell density increased, but was not affected by calcium. These results indicate that the SV40 immortalized human keratinocytes, maintained in a low calcium defined medium, partially respond to changes in extracellular calcium concentration.  相似文献   
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