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91.
BACKGROUND: Cerebrovascular diseases are very common in hemodialysis (HD) patients. Silent cerebral infarction (SCI) has not been investigated in HD patients although it may be a significant risk factor for cerebrovascular diseases. HYPOTHESIS: Chronic renal failure may be an independent risk factor for SCI and cerebrovascular diseases. METHODS: Cranial magnetic resonance imaging (MRI) was performed on 123 HD patients without symptomatic cerebrovascular disease and on 52 control subjects. We investigated the prevalence of SCI and performed cross-sectional study using multiple logistic analysis to assess the relationship between SCI and the risk factors. RESULTS: The prevalence of SCI was significantly higher in HD patients than in the healthy control group (60 patients (48.8%) vs. 5 patients (9.6%), chi(2) = 22.4, p < 0.0001). Multiple logistic regression analysis with all subjects showed that independent risk factors of SCI were chronic renal failure, hypertension, smoking and age (R(2) = 0.468, p < 0.0001). In only the HD patient group, age and smoking were shown to be independent risk factors of SCI (R(2) = 0.378, p < 0.0001) while HD duration and hypertension were not. CONCLUSIONS: The findings of the present study indicate that chronic renal failure maintained by hemodialysis increases the prevalence of SCI and that age and smoking habits are also significantly associated with SCI in HD patients.  相似文献   
92.
This study examined the role of mitogen-activated protein (MAP) kinase in PDGF-BB-induced proliferation and gene expression of human mesangial cells (MC). PDGF-BB stimulation of MC increased mRNA for transforming growth factor-beta1 (TGF-beta1), monocyte chemoattractant protein-1 (MCP-1), and plasminogen activator inhibitor-1 (PAI-1) and increased the cell numbers. To inhibit activation of extracellular signal-regulated kinase (ERK), c-Jun amino-terminal kinase (JNK), and p38, MC were infected with recombinant adenovirus containing dominant-negative mutants of ERK, JNK, and p38 (Ad-DN-ERK, Ad-DN-JNK, Ad-DN-p38, respectively), respectively. Infection of MC with Ad-DN-ERK or Ad-DN-JNK inhibited PDGF-BB-induced increase in [(3)H]thymidine incorporation and cell numbers, whereas Ad-DN-p38 did not. Ad-DN-ERK inhibited MCP-1 and PAI-1 mRNA expression in MC, but not TGF-beta1. Ad-DN-JNK and Ad-DN-p38 inhibited TGF-beta1 and MCP-1 mRNA expression, but not PAI-1. The inhibition of activator protein-1 (AP-1) in MC, by adenovirus containing dominant-negative mutant of c-Jun (Ad-DN-c-Jun), inhibited PDGF-BB-induced cell proliferation and TGF-beta1, MCP-1, and PAI-1 expressions. Furthermore, Ad-DN-JNK or Ad-DN-p38, but not Ad-DN-ERK, attenuated PDGF-BB-induced AP-1 activation in MC, indicating the involvement of JNK and p38 in AP-1 activation. Our results indicated that ERK and JNK, but not p38, participated in PDGF-BB-induced MC proliferation. PDGF-BB-induced expression of TGF-beta1 was mediated by JNK and p38, MCP-1 expression was through ERK, JNK, and p38, whereas PAI-1 expression was due to only ERK. AP-1 activation, which was partially due to JNK and p38 activations, was involved in MC proliferation and these three gene expressions. Thus, three MAP kinases seem to contribute to progression of glomerular disease via different molecular mechanisms.  相似文献   
93.
BACKGROUND: Cytokeratin immunostaining is the most common method used to identify micrometastatic cancer cells from the lymph nodes. However, contamination with hyalinized cytokeratin particles, frequently observed in the lymph nodes of esophageal cancer patients, can lead to misinterpretation of cytokeratin immunostaining. MATERIALS AND METHODS: Cytokeratin immunostaining (AE1/AE3) of surgically removed lymph nodes was performed for 41 cases of node-negative, but locally advanced (T3, T4), esophageal cancer patients. Cytokeratin immunoreactivity (CK) was classified as micrometastasis (MM) or cytokeratin deposit (CD) by the presence or absence of tumor nuclei in serial sections given hematoxylin-eosin staining. RESULTS: CK (+) was observed in 18 patients (44%), including 11 with MM (+) (27%) and 10 with CD (+) (24%). There was no correlation between MM and CD, and neither was associated with clinicopathological factors, except for a high incidence of preoperative chemotherapy in CD (+) patients. The presence of CK did not affect postoperative survival of esophageal cancer patients at this limited stage, showing a 5-year survival rate of 57% for CK (+) and 64% for CK (-) (P = 0.6064). Interestingly, patients with MM (+) showed poorer prognosis than MM (-) (5-year survival: 28% vs 79%, P = 0.0188), while CD (+) patients tended to display better prognosis than CD (-) ones (5-year survival: 78% vs 56%, P = 0.1860). CONCLUSIONS: Evaluation by cytokeratin immunostaining of lymph nodes requires careful discrimination of CD from MM, in order to allow MM to be used as a prognostic factor for esophageal cancer patients.  相似文献   
94.
PURPOSE: The present study was aimed at clarifying the clinical significance of posterior cerebral artery (PCA) stenosis/occlusion in pediatric and adult moyamoya disease. SUBJECTS AND METHODS: This study included a total of 132 patients (52 children and 80 adults) who were diagnosed as by cerebral angiography having moyamoya disease. CT or MRI was performed to examine the location of cerebral infarction in all subjects. Cerebral blood flow and vasoreactivity to acetazolamide were measured in 80 patients before surgery, using single photon emission computed tomography (SPECT). Three-dimensional MR angiography (3D-MRA) was repeated in 32 pediatric patients after surgery in order to clarify the natural course of the PCA stenosis/occlusion. RESULTS: Of 264 sides in 132 patients, PCA stenosis/occlusion was observed in 50 sides of 40 patients (30.3%). Its incidence was significantly higher in ischemic-type patients than in hemorrhagic-type and asymptomatic patients, and was higher in patients in the advanced stage of the disease. The hemisphere ipsilateral to PCA stenosis/occlusion had higher incidence of ischemic symptoms, cerebral infarction, and impaired cerebral hemodynamics. TIA (hemianopsia) or cerebral infarction in the occipital lobe was noted in 4 (10%) of 40 patients during follow-up periods after bypass surgery for anterior circulation. Of 32 pediatric patients, none showed progression of PCA stenosis on 3D-MRA during follow-up periods. CONCLUSIONS: The present study showed that the involvement of PCA could increase the risk of TIA and/or cerebral infarction in both anterior and posterior circulation areas, suggesting that the PCA plays an important collateral role in moyamoya disease.  相似文献   
95.

Purpose

To establish the most effective methods of postoperative surveillance to detect early recurrence of lung adenocarcinoma.

Methods

The subjects of this retrospective study were 485 patients with p-stage I–III lung adenocarcinoma, who underwent postoperative surveillance. We examined the sites and detection modes of recurrence and calculated the recurrence-free probabilities. Patients with stage I disease were divided into low- and high-risk recurrence groups using a risk score calculated by assigning points proportional to risk factor regression coefficients.

Results

Of the 112 patients with recurrence, 86 had intrathoracic recurrence. Routine computed tomography (CT) revealed recurrence in 60 patients. The recurrence-free probability curves showed that 95% of recurrences were identified within the first 4 years after resection in patients with stage II/III disease. In patients with stage I disease, the predictors of recurrence included male sex, positive pleural lavage cytology, moderate-to-poor differentiation, and visceral pleural invasion. Postoperative recurrences were detected throughout the follow-up period in the high-risk group.

Conclusions

Routine chest CT plays an important role in the postoperative surveillance of lung adenocarcinoma. We recommend intensive follow-up during the early post-resection period for patients with advanced stage disease and long-term follow-up for high-risk patients with stage I disease.
  相似文献   
96.

Objective

The purpose of this study was to investigate the differences between spinal metastasis and osteoporotic compression fractures on plain X-ray images, focusing on asymmetrical vertebral collapse and fracture level.

Materials and methods

This study included 180 patients with pathological collapse from spinal metastasis (188 vertebrae) who were treated at our institution and 70 patients (92 vertebrae) with osteoporotic compression fractures. Anteroposterior X-ray images of the lower thoracic and lumbar spine were evaluated for asymmetrical collapse deformity.

Results

Asymmetrical collapse was found in 134 vertebrae (71.3%) with metastasis, and in 20 osteoporotic vertebrae (21.7%); this difference was significant (p < 0.0001). The asymmetrical collapse angle in spinal metastasis patients ranged from 0 to 18°, with a mean of 7.0 and a standard deviation (SD) of 4.5. In contrast, the asymmetrical collapse angle in patients with osteoporotic fractures ranged from 0 to 13°, with a mean of 3.1 and a SD of 2.8. The difference in collapse angle between the two groups was statistically significant (p < 0.001). The cutoff value to suspect spinal metastasis was determined to be 5° or more (sensitivity 0.67, specificity 0.74). Fracture at Th10 or below L3 was found in 20.2% of spinal metastasis patients; only 3% of osteoporotic fractures occurred at these levels.

Conclusion

Asymmetrical collapse with an angle of 5° or more and fractures at atypical levels on plain radiographs can be useful clues to spinal metastasis.  相似文献   
97.
Objective:   The management of lower urinary tract symptoms that persist after radical prostatectomy remains to be established. We investigated whether an α1-blocker, naftopidil, improves LUTS in patients ≥1 year after radical prostatectomy.
Methods:   A total of 29 male patients received 25 mg/day of naftopidil for the first week, then 75 mg/day for 4 weeks. The frequency-volume chart, international prostate symptom score and quality of life index (QOL) were examined before and at the end of the 5-week administration in all subjects.
Results:   Total international prostate symptom score (I-PSS) and I-PSS subtotals associated with voiding symptoms and storage symptoms were significantly decreased at 5 weeks compared with baseline ( P  < 0.001 each). QOL index was significantly improved with naftopidil for 5 weeks ( P  < 0.001). From analyses of the frequency-volume chart, mean and maximum volume/void were significantly increased ( P  < 0.05 each).
Conclusion:   Lower urinary tract symptoms detected in patients ≥1 year after radical prostatectomy were markedly improved with administration of naftopidil at 75 mg/day. These symptoms could represent a novel target for medical treatment by improved understanding of the symptom pathology in the near future.  相似文献   
98.
Purpose  We conducted a double-blind placebo-controlled study to investigate the effects of the intraoperative intravenous infusion of adenosine 5′-triphosphate (ATP) on intraoperative hemodynamics and postoperative pain in patients undergoing major orofacial surgery. Methods  Thirty patients (age, 16–42 years; 16 males/14 females) scheduled for sagittal split ramus osteotomy were assigned in a double-blind fashion to receive intraoperative intravenous infusion of ATP (n = 15) or saline (n = 15). Anesthesia was induced and maintained with propofol, fentanyl, and vecuronium. Local anesthesia was added for intraoperative analgesia. In the ATP group, ATP was infused at a rate of 160 μg·kg−1·min−1 throughout surgery. Postoperative pain was managed with intravenous patient-controlled analgesia (PCA) with morphine. The intensity of postoperative pain was assessed with a verbal numeric rating scale (NRS). Morphine consumption was also assessed. Results  There were no differences in demographic, anesthetic, and surgical data between the ATP and placebo groups. Intraoperatively, ATP effectively suppressed responses of blood pressure and heart rate to painful surgical stimuli. There were no differences in postoperative NRS scores between the two groups. However, postoperative morphine consumption was significantly less in the ATP group, compared with the placebo group, throughout the 72-h postoperative observation period. Cumulative morphine consumption for 72 h postoperatively was 47% less with ATP, compared with placebo. No adverse effect of ATP was observed. Conclusion  Our data suggest that intraoperative ATP infusion can blunt hemodynamic responses to surgical stimuli and produce prolonged analgesia in patients undergoing major orofacial surgery.  相似文献   
99.
Few studies have analyzed Cathepsin K (CatK) expression in human osteoarthritic tissues. We investigated CatK expression and activation in human articular cartilage using clinical specimens. Human osteoarthritic cartilage was obtained during surgery of total hip arthroplasty (n = 10), and control cartilage was from that of femoral head replacement for femoral neck fracture (n = 10). CatB, CatK, CatL, CatS, and Cystatin C (CysC) expressions were evaluated immunohistochemically and by real‐time PCR. Intracellular CatK protein was quantified by ELISA. Intracellular CatK activity was also investigated. Osteoarthritis (OA) chondrocytes were strongly stained with CatK, particularly in the superficial layer and more damaged areas. CatB, CatL, CatS, and CysC were weakly stained. CatK mRNA expression was significantly higher in OA group compared to that in control group (p = 0.043), whereas those of CatB, CatL, CatS, and CysC did not differ significantly. Mean CatK concentration (4.83 pmol/g protein) in OA chondrocytes was higher than that (3.91 pmol/g protein) in control chondrocytes (p = 0.001). CatK was enzymatically more activated in OA chondrocytes as compared with control chondrocytes. This study, for the first time, revealed increased CatK expression and activation in human OA cartilage, suggesting possible crucial roles for it in the pathogenesis of osteoarthritic change in articular cartilage. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:127–134, 2016.  相似文献   
100.

Background

We previously demonstrated validation of the Comprehensive International Classification of Functioning, Disability and Health Core Set for Diabetes Mellitus (ICF-CS for DM) in patients with diabetic nephropathy (DMN). The objective of the present study was to identify differences in experience of physical and psychosocial problems between DMN patients with and without hemodialysis (HD), and diabetes patients without nephropathy using the ICF-CS for DM.

Methods

A total of 302 diabetes outpatients (men, 68 %; mean age, 62 years) were interviewed using four components of the ICF-CS for DM including “Body functions”, “Body structures”, “Activities and participation”, and “Environmental factors”.

Results

The mean number of categories in which difficulty was experienced in the four components was significantly greater in DMN patients with HD followed by DMN patients without HD, and diabetes patients without nephropathy (23.9 vs. 18.0 vs. 13.1, respectively). Multivariate logistic regression models revealed that, compared with diabetes patients without nephropathy, diabetes patients with nephropathy were more likely to have difficulty with physical problems and social activities and participation. Among DMN patients, dialysis patients were found to have larger numbers of problems, and face difficulty with employment status after adjusting for sex, age, type, and duration of diabetes.

Conclusion

The results of this study using the ICF-CS for DM identified the areas for improvement among physical and psychosocial problems in DMN patients with and without HD in contrast to diabetes patients without nephropathy.
  相似文献   
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