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1.
In acetabular dysplasia of the hip joint accompanied by a giant acetabular bone cyst, rotational acetabular osteotomy may cause serious complications, such as bone necrosis after surgery or fracture of the fragile acetabulum during the operation. In a patient with this condition, we performed a two-stage operation: first, autogenous bone grafting supplemented with hydroxyapatite filling, then rotational acetabular osteotomy (after new bone formation had been assured). Radiographs and CT scans showed favorable fusion of the grafted bone. Some 18 months after the second operation, arthrograms showed no inflow of contrast medium from the articular cavity into the bone cyst region, although this had been observed before treatment. Thus, an effective remodeling of bony congruency was indicated in the mobile acetabulum 5 years after the second operation. This two-stage operation appears to be useful for correcting acetabular dysplasia accompanied by a giant bone cyst and to carry a reduced risk of serious complications, such as deterioration of the articular surface of the acetabulum or necrosis of the translocated acetabulum.  相似文献   
2.
The selective increase in tumor blood flow under angiotensin II-induced hypertension was observed to be the result of passive vascular beds irresponsive to angiotensin II. We investigated whether or not increased tumor blood flow resulting from angiotensin II-induced hypertension could be recognized on angiographic findings. Angiography under angiotensin II-induced hypertension was performed in 51 patients with various cancers, and angiographic findings indicating increased tumor vascularity were recognized in 40 (78.4%) of them. Based on the assumption that the increase in tumor oxygen tension was brought about by increased tumor blood flow, the possibility of utilizing this phenomenon in hyperbaric oxygenation radiotherapy was suggested.  相似文献   
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To evaluate the biological reactions to metal ions potentially released from prosthetic implants, we examined the ability of metal ions to produce bone-resorbing cytokines and the underlying mechanism using synoviocytes and bone marrow (BM) macrophages. The cells were incubated with NiCl(2), CoCl(2), CrCl(3) or Fe(2)(SO(4))(3) at optimal concentrations, which are detectable in joint fluid following total joint arthroplasty. The production of interleukin-1beta, interleukin-6 and tumor necrosis factor-alpha were enhanced by all metal ions tested as determined by enzyme-linked immunosorbent assay. From the results of electrophoresis mobility shift assay, all metal ions enhanced the DNA-binding activity of nuclear factor kappaB (NF-kappaB), and p50-p65 heterodimers and p50 homodimers were the major subunits. These effects of the metal ions were considerably blocked by pyrrolidine dithiocarbamate (PDTC) known as a radical scavenger. An electron spin resonance study clearly demonstrated the ability of metal ions to generate activated oxygen species (AOS), especially hydroxyl radicals (*OH), which accounts for PDTC-blockade of metal ion-induced NF-kappaB activation and subsequent cytokine production. Taken together, our data raised the possibility that small amounts of metal ions released from prosthetic implants activate synoviocytes and BM macrophages through the AOS-mediated process (i.e. the redox pathway), and contribute to the initiation of osteolysis at the bone-implant interface.  相似文献   
5.
Immunohistochemical studies were performed to clarify the significance of the expression or overexpression of epidermal growth factor (EGF), EGF-receptor (EGFR), p53, v- erb B, ras p21 in 23 cases each of tubular adenoma and adenocarcinoma. The expression of EGF, EGFR, p53, v- erb B, and ras p21 in paraffin-embedded tissues, from 46 patients with colorectal tumors (adenoma: 23 cases; 14 mild dysplasia, six moderate dysplasia, three severe dysplasia, adenocarcinoma: 23 cases; 17 well differentiated, two moderately differentiated, three poorly differentiated, one mucinous carcinoma was analyzed immunohistochemically using anti-EGF, EGFR, p53, v- erb B and ras p21 antibodies. The EGF and ras p21 tended to express more strongly in carcinoma cases than in the adenoma cases, and in severe and moderate dysplasia than in mild dysplasia (EGF: stained positive in five adenomas [21.74%] and 17 adenocarcinomas [73.91%]; ras p21: stained positive in six adenomas [26.09%] and 14 adenocarcinomas [60.87%]. The EGFR stained positive in two adenomas (8.70%) and two adenocarcinomas (8.70%). The p53 and v- erb B showed positive staining only in the carcinoma cases (p53: stained positive in four cases [17.39%]; v- erb B: stained positive in eight cases [34.78%]). This study suggests that these factors seem to have some role in the progression of colon neoplasms. It suggests that genetic alteration is not always equal to the overexpression of protein products, but that it reflects them well, and that the staining makes some contribution to differential diagnosis in colorectal neoplasms.  相似文献   
6.
Two cytokines IL-4 and IL-12 are known to determine the balance between T(h)1 and T(h)2 development. In addition to IL-4 production of V(alpha)14(+) NKT cells, they have recently been demonstrated to have the capacity to stimulate IL-12 production by antigen-presenting cells (APC). This study demonstrates that IFN-gamma is absolutely required for the NKT cell-stimulated IL-12 production. Culture of B cell-depleted spleen cells from C57BL/6 mice with alpha-galactosylceramide (alpha-GalCer) capable of selectively stimulating V(alpha)14/J(alpha)281(+) NKT cells resulted in the production of IL-12 together with IL-4. Whereas IL-4 production occurred in culture of IFN-gamma(-/-) C57BL/6 splenocytes, the same culture failed to generate IL-12 production. While IL-12 production induced during culture of V(alpha)14(+) NKT cells and APC depended on the interaction between CD40 ligand on NKT cells and CD40 on APC, the expression levels of these key molecules were comparable in cells from wild-type and IFN-gamma(-/-) mice. Addition of rIFN-gamma to alpha-GalCer stimulated IFN-gamma(-/-) splenocyte culture, and administration of rIFN-gamma to alpha-GalCer-injected IFN-gamma(-/-) mice resulted in the restoration of IL-12 production in vitro and in vivo. These results illustrate a mandatory role for IFN-gamma in V(alpha)14(+) NKT cell-stimulated IL-12 production by APC.  相似文献   
7.
While poorly-absorbed sugar alcohols such as sorbitol are widely used as sweeteners, they may induce diarrhea in some individuals. However, the factors which determine an individual’s susceptibility to sugar alcohol-induced diarrhea remain unknown. Here, we show that specific gut bacteria are involved in the suppression of sorbitol-induced diarrhea. Based on 16S rDNA analysis, the abundance of Enterobacteriaceae bacteria increased in response to sorbitol consumption. We found that Escherichia coli of the family Enterobacteriaceae degraded sorbitol and suppressed sorbitol-induced diarrhea. Finally, we showed that the metabolism of sorbitol by the E. coli sugar phosphotransferase system helped suppress sorbitol-induced diarrhea. Therefore, gut microbiota prevented sugar alcohol-induced diarrhea by degrading sorbitol in the gut. The identification of the gut bacteria which respond to and degrade sugar alcohols in the intestine has implications for microbiome science, processed food science, and public health.  相似文献   
8.
A study of the intracellular Ca2+ ([Ca2+]i) response of differentiated neuroblastoma x glioma hybrid cells (NG108-15 cell) to enkephalin (EK) was carried out by fura-2 video-imaging. EK alone did not influence [Ca2+]i in single cells. The opioid did, however, induce a marked [Ca2+]i rise, when the cells were incubated with bradykinin (BK) prior to the EK treatment. Such BK-assisted stimulation of the differentiated hybridoma cells by EK was completely abolished by pertussis toxin treatment. These results suggest that in single NG108-15 cells, EK induces Ca2+ mobilization which is assisted by cross-talk between the EK and BK receptor systems via a pertussis toxin-sensitive G protein.  相似文献   
9.
The prevalence of microalbuminuria and its relationship to cardiovascular disease risk factors were examined in subjects participating in an annual physical and laboratory examination program. The urinary albumin concentration and the urinary albumin/creatinine ratio were determined in morning urine specimens. A turbidimetric immunoassay was used for the measurement of urinary albumin. Of the 731 subjects, 41 (5.6%) who were weakly positive or positive on a routine dipstick test for protein were excluded from the final analysis of data. Microalbuminuria was present in 14.5% of the men, in 12.4% of the women, and in 13.2% of the entire subject population when defined as a urinary albumin concentration of 30-299 microgram/ml. The prevalence of microalbuminuria was significantly higher in subjects with a high normal blood pressure (15.0%) or hypertension (26.2%) as compared with normotensive subjects (6.5%). Subjects with impaired glucose tolerance (24.3%) or hyperglycemic subjects (50.0%) had a significantly higher prevalence of microalbuminuria than normoglycemic subjects (11.3%). The prevalence of microalbuminuria was significantly higher in subjects with left ventricular hypertrophy (47.1%) as compared with those with normal electrocardiograms (11.3%). A good correlation was observed between urinary albumin concentration and albumin/creatinine ratio, and both showed a significant positive correlation with age, systolic and diastolic blood pressures, and fasting plasma glucose, total serum protein, albumin, and triglyceride levels, but not with angiotensin-converting enzyme activity. Multiple regression analysis demonstrated that both the urinary albumin concentration and the albumin/creatinine ratio show a significant positive correlation with systolic blood pressure and fasting plasma glucose. The prevalence of microalbuminuria was about 13% in this Japanese cohort, and the systolic blood pressure and the fasting plasma glucose level were demonstrated as independent risk indicators for both urinary microalbumin level and urinary microalbumin/creatinine ratio.  相似文献   
10.
Several factors such as proteinuria and renal fibrosis may be important in the progression of many forms of chronic renal diseases. The purposes of the current study were to investigate the progressive renal failure of the rats with surgical renal mass reduction (RMR) and the effect of the angiotensin-converting enzyme (ACE) inhibitor, lisinopril, and to document correlation of several factors associated with progressive renal failure. Rats were subtotal (5/6) nephrectomized by resection of the renal poles and sham-operated. The functional, histological and haematological changes of the rats were studied for up to 10 weeks. After 2 weeks of RMR, oral administration of lisinopril (10 mg kg(-1) per day) was performed for 8 weeks. RMR resulted in progressive renal failure with proteinuria, monocyte/macrophage (ED1+) infiltration, anaemia as assessed by haemoglobin and haematocrit (Htc), renal hypertrophy as assessed by left kidney to body weight ratio (BKW/BW), and renal fibrosis as assessed by glomerular lesions and tubulointerstitial changes. Lisinopril exhibited renoprotection with antiproteinuric effect and inhibition of monocyte/macrophage (ED1+) infiltration. However, beneficial effect of lisinopril on anaemia was not observed. At 10 weeks after surgery, severity of proteinuria positively correlated with plasma creatinine (Pcr), BKW/BW, histological damage, and systolic blood pressure, and negatively correlated with haemoglobin. Severity of tubulointerstitial changes positively correlated with Pcr and blood urea nitrogen, and negatively correlated with haemoglobin and Htc. Moreover, monocyte/macrophage (ED1+) infiltration positively correlated with severity of proteinuria and tubulointerstitial changes. These findings strongly support that proteinuria, monocyte/macrophage infiltration and renal fibrosis appear to play principal roles in the progressive renal failure with anaemia and renoprotection of ACE inhibition may be mediated by multiple actions of ACE inhibitor. The present study confirms that rats with RMR is useful to explore target molecules for renoprotective drugs and evaluate renoprotective effect of new molecular entities.  相似文献   
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