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101.
To investigate the role of p53 abnormalities in predicting the survival of patients with non-small cell lung cancer (NSCLC), polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and immunohistochemical analyses were performed on 74 and 67 tumor samples, respectively, from patients with pathological stage I-IIIa NSCLC. An abnormally migrating SSCP band was observed in 21 of 74 (28%) tumor specimens. DNA sequence analysis revealed 23 intragenic mutations including 3 small deletions and 20 point mutations. Immunohistochemical analysis using the DO-7 monoclonal antibody showed abnormal expression of p53 in 27 of 67 (40%) patients. The concordance rate between immunohistochemical and PCRSSCP analyses was 73% (49/67) in this study. Univariate and multivariate analyses demonstrated that abnormal expression of p53 may be associated with prolonged survival (p=0.0997 and 0.0099, respectively). In contrast, no relationship was observed between p53 mutation and overall survival (0.6968). These results suggest that p53 status and the survival outcome changes between immunohistochemical and mutational analyses in stage I-IIIa NSCLC.  相似文献   
102.
Three myoepitheliomas (MEOs) derived from the salivary glands were examined immunohistochemically. Proliferating cell nuclear antigen (PCNA)-positive cells were very rare (less than 2% of all tumor cells) in localized tumors of case 1 (epithelioid) (E-oid) cells) and case 2 (plasmacytoid) (P-toid) cells with a small number of spindle-shaped cells), but the percentage of PCNA-positive cells was high (21.8%) in case 3 (clear cells) exhibiting bone destruction. Strong c-myc expression was detected in all the tumors, but p53 or c-erbB-2 protein was not detected in any of the cases. More than half of the clear cells were positive for epidermal growth factor (EGF), while fewer tumor cells in cases 1 and 2 expressed EGF. A few tumor cells in cases 2 and 3 were positive for EGF-receptor (R). Keratin was most prominent in the E-oid cells, The P-toid cells were most strongly positive for S-100 protein followed by the E-oid and clear cells. More than half of the spindle-shaped cells and one-third of the E-oid cells were positive for alpha-smooth muscle actin (alpha-SMA), but less than 5% of the clear cells and none of the P-toid cells were positive for alpha-SMA. These results suggest that tumor cells in MEO are heterogenous and have different proliferation activities.  相似文献   
103.
It is well known that physical exercise can reduce coronary risk factors. But how an aerobic exercise modifies coronary risk factors in relation to severity and physical fitness is still controversial. Fifty-four middle-aged women (mean age, 55 years) completed a 6-month on-site and home-based anaerobic threshold-level exercise program. The changes in coronary risk factor profiles were observed during the pre-intervention and intervention periods. Before the intervention (during control period), most coronary risk factors showed a rather unfavorable trend. After the program, their mean body weight decreased from 56.7 to 55.7 kg (p>0.05) and the proportion of body fat from 30.9 to 27.9% (p>0.05) without any reduction in lean body mass. Systolic blood pressure (SBP) decreased from 129.0 to 125.0 mm Hg (p>0.05) and diastolic blood pressure from 79.5 to 76.6 mm Hg (p>0.05). Fasting plasma glucose (FPG) declined from 109.6 to 103.4 mg/dl (p>0.05). Changes in SBP and FPG were most remarkable in their respective worst tertile. Serum lipids improved only modestly. Maximum oxygen uptake increased from 23.6 to 26.1 ml/kg/min (p>0.01). However, no significant correlations were found between changes in coronary risk factors and those in physical fitness. We conclude that the 6-month aerobic exercise program would modify women’s coronary risk factors depending on their initial values, probably independently of the changes in physical fitness.  相似文献   
104.
We describe a case of pilocytic astrocytoma of the cerebellum mimicking an acoustic schwannoma. The tumour protruded into the porus acusticus and enlarged the internal auditory meatus, which is a quite unusual characteristic of glial tumours. Received: 2 February 1999 Accepted: 21 April 1999  相似文献   
105.
Liver regeneration in a patient with fulminant hepatic failure (FHF) who underwent living-related partial liver transplantation (LRLT) was investigated regarding hepatic growth factors. The patient was a 16-yr-old Japanese male who developed severe subacute FHF. LRLT was performed using an extended left lobe of the ABO matched patient's mother. In the recipient, the pre-transplant levels of both plasma hepatocyte growth factor (HGF) and transforming growth factor (TGF)-beta were extremely high and rapidly decreased following the liver replacement. The liver volume evaluated using a CAT scan increased 195% after 2 wk in graft liver and 110% after 2 wk in the hepatectomized donor. The explanted liver (FHF liver), the liver from donor (normal liver), and the graft liver [the 3rd post-transplant day (POD 3)] were all investigated immunohistochemically. FHF liver: No liver regeneration was observed [proliferative cell nuclear antigen (PCNA) labeling index (L.I.): 0%]. In the liver, both HGF in the hepatocytes and c-met on the membrane of the hepatocytes were positive. TGF-beta was positive in the hepatocytes and no apoptosis was detected by the TUNEL method. Donor liver (POD 0): Few PCNA stained hepatocytes were detected. No HGF was detected but c-met was clearly detected on the cell membrane of the hepatocytes. Neither TGF-beta nor apoptosis was detected. Graft liver (POD 3): The PCNA L.I. was conspicuous at 40%. HGF was positive in non-parenchymal cells and c-met was positive in the cytoplasm of the hepatocytes. TGF-beta was negative while apoptosis was positive in the zone 3 hepatocytes. In conclusion, these findings suggested that the liver of the patient with FHF did not respond to liver regenerative stimulus, in part, through involvement of inhibitor TGF-beta. On POD 3, the transplanted graft was in a vigorous regenerative status in comparison to that in the hepatectomized donor. The HGF/c-met system is thought to be involved in the mechanism of regeneration. Intrahepatic apoptosis was detected in the graft on the 3rd post-transplant day probably due to transient ischemia in the liver, which was not related to the Fas/Fas-ligand system.  相似文献   
106.
The spontaneously immortalized S16 Schwann cell line expresses higher levels of myelin-associated glycoprotein (MAG) and PO glycoprotein and their messenger RNAs when grown at high density than at low density [Sasagasako et al: J Neurochem 1996;66:1432-1439]. This up-regulation of myelin protein expression at high density is not associated with decreased cellular proliferation and may be caused by direct cell-to-cell contact. To investigate the hypothesis that increased mRNA levels for myelin proteins are caused by contact between Schwann cells, sparse S16 cell cultures were treated for 48 h with plasma-membrane-enriched fractions isolated from dense S16 cells. The treatment had no effect on the proliferation of the cells, but MAG and PO mRNAs were elevated 2- and 1.3-fold, respectively, in comparison to untreated cells. These effects on levels of myelin protein mRNAs were eliminated by pretreatment of the membrane fraction with heat or trypsin and were not caused by plasma membrane fractions from NIH 3T3 cells. These data support the hypothesis that homotypic contact between Schwann cells up-regulates expression of myelin proteins and suggest the possibility of autotypic contact-mediated regulation of myelinogenesis by adjacent spiraled membranes of individual Schwann cells.  相似文献   
107.
BACKGROUND: The renin-angiotensin system is thought to be involved in the progression of glomerulonephritis (GN) into end-stage renal failure (ESRF) because of the observed renoprotective effects of angiotensin-converting enzyme inhibitors (ACEIs). However, ACEIs have pharmacological effects other than ACE inhibition that may help lower blood pressure and preserve glomerular structure. We previously reported a new animal model of progressive glomerulosclerosis induced by a single intravenous injection of an anti-Thy-1 monoclonal antibody, MoAb 1-22-3, in uninephrectomized rats. Using this new model of progressive GN, we examined the hypothesis that ACEIs prevent the progression to ESRF by modulating the effects of angiotensin II (Ang II) on the production of transforming growth factor-beta (TGF-beta) and extracellular matrix components. METHODS: We studied the effect of an ACEI (cilazapril) and an Ang II type 1 receptor antagonist (candesartan) on the clinical features and morphological lesions in the rat model previously reported. After 10 weeks of treatment with equihypotensive doses of cilazapril, cilazapril plus Hoe 140 (a bradykinin receptor B2 antagonist), candesartan, and hydralazine, we examined systolic blood pressure, urinary protein excretion, creatinine clearance, the glomerulosclerosis index, and the tubulointerstitial lesion index. We performed a semiquantitative evaluation of glomerular immunostaining for TGF-beta and collagen types I and III by immunofluorescence study and of these cortical mRNA levels by Northern blot analysis. RESULTS: Untreated rats developed massive proteinuria, renal dysfunction, and severe glomerular and tubulointerstitial injury, whereas uninephrectomized control rats did not. There was a significant increase in the levels of glomerular protein and cortical mRNA for TGF-beta and collagen types I and III in untreated rats. Cilazapril and candesartan prevented massive proteinuria, increased creatinine clearance, and ameliorated glomerular and tubulointerstitial injury. These drugs also reduced levels of glomerular protein and cortical mRNA for TGF-beta and collagen types I and III. Hoe 140 failed to blunt the renoprotective effect of cilazapril. Hydralazine did not exhibit a renoprotective effect. CONCLUSION: These results indicate that ACEIs prevent the progression to ESRF by modulating the effects of Ang II via Ang II type 1 receptor on the production of TGF-beta and collagen types I and III, as well as on intrarenal hemodynamics, but not by either increasing bradykinin activity or reducing blood pressure in this rat model of mesangial proliferative GN.  相似文献   
108.
BACKGROUND: The pathogenesis of IgA nephropathy is still obscure. The aim of this study was to investigate whether the fundamental pathogenesis of IgA nephropathy lies in bone marrow stem cells (BMCs). METHODS: We used donors of two different strains for bone marrow transplantation (BMT) into mice with a high content of serum IgA (ddY strain, HIGA mice), a murine model of IgA nephropathy. One group (B6-->HIGA, N = 5) received BMCs of C57BL/6j (B6) mice, and the other (HIGA-->HIGA, N = 8) were reconstituted with BMCs of HIGA mice. RESULTS: Twenty-six weeks after BMT, in B6-->HIGA mice, mesangial deposits of IgA and C3 were statistically milder than those in HIGA-->HIGA mice. Light microscopic observations disclosed that glomerular sclerosis and mesangial matrix expansion in B6-->HIGA mice were decreased compared with those in HIGA-->HIGA mice. These B6-->HIGA mice also excreted less urinary albumin than HIGA-->HIGA mice. Furthermore, serum levels of IgA in B6-->HIGA mice were markedly lower than those in HIGA-->HIGA mice. Size analysis of serum IgA revealed that macromolecular IgA were notably lower in B6-->HIGA mice than in HIGA-->HIGA mice. CONCLUSIONS: Our results suggest that qualitative and quantitative changes of serum IgA are determined at the level of stem cells, and that BMT from normal donors can attenuate glomerular lesions in HIGA mice. This approach may offer a new avenue to study the pathogenesis of IgA nephropathy.  相似文献   
109.
BACKGROUND/AIMS: Eyes with epiretinal membranes (ERMs) often have alterations of retinal vessels. The authors studied perifoveal microcirculation in eyes with epiretinal membranes (ERMs) using scanning laser ophthalmoscope (SLO) fluorescein angiography. METHODS: Mean capillary blood flow velocity (CFV) was measured as an index of perifoveal microcirculation by SLO fluorescein angiography in 26 eyes with ERMs (19 eyes with idiopathic epiretinal membranes, seven eyes with epiretinal membranes after retinal detachment surgery) before and 6 months after vitreous surgery, and in 23 healthy control subjects. RESULTS: The mean CFV was significantly reduced in eyes with ERMs compared with healthy controls (p=0.012), and the postoperative mean CFV was significantly increased compared with the preoperative mean CFV (p=0.041). CONCLUSION: Significant changes of capillary blood flow velocity in the perifoveal areas were observed between normal subjects and eyes with epiretinal membranes. This indicates that eyes with ERMs show abnormal haemodynamics in the perifoveal capillaries.  相似文献   
110.
Ocular involvement, mainly uveitis or retinochoroiditis, is common in various systemic diseases, such as endogenous endophthalmitis, Lyme disease, human T-cell lymphotropic virus type I infection, toxoplasmosis, and toxocariasis. Recent progress, especially in laboratory microbiologic testing, has enabled us to reliably diagnose many formerly idiopathic intraocular inflammatory diseases. A group of systemic infectious diseases, including those discussed here, are implicated as a body of emerging or re-emerging diseases that have appeared in the past two decades and are thought to have a close relation with global socioenvironmental changes. This paper discusses recent clinical and experimental studies of the most important systemic infectious diseases that affect the eye.  相似文献   
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