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91.
Vascular smooth muscle cell (VSMC) proliferation and extracellular matrix (ECM) accumulation play key roles in the development and the progression of vascular remodeling such as transplant arteriosclerosis and restenosis. The present study examined the effects of sirolimus (SRL) on platelet-derived growth factor (PDGF)-induced fibronectin secretion, collagen synthesis, and the related signaling pathways including reactive oxygen species (ROS) and mitogen-activated protein kinases (MAPK) in rat VSMCs. Primary rat VSMCs were isolated from male Sprague-Dawley rats. Growth arrested, synchronized cells were treated with various concentrations of SRL before the addition of PDGF at 10 ng/mL. Proliferating cell nuclear antigen expression, fibronectin secretion, and the activation of extracellular signal-regulated protein kinase (ERK) and p38 MAPK were assessed by Western blot analysis, collagen synthesis by [(3)H]-proline incorporation, and cellular ROS by flow cytometry. PDGF (10 ng/mL) increased VSMC proliferation by 1.7-fold, fibronectin secretion by 1.5-fold, collagen synthesis by 2.1-fold, cellular ROS by 1.6-fold, and activation of ERK and p38 MAPK by 3.3- and 3.9-fold compared to controls. SRL above 1 nmol/L inhibited PDGF-induced VSMC proliferation and collagen synthesis but not PDGF-induced fibronectin secretion, cellular ROS, and activation of ERK and p38 MAPK. These data demonstrated that PDGF increased ECM synthesis as well as proliferation through cellular ROS and subsequent MAPK activation and that SRL inhibited PDGF-induced VSMC proliferation and collagen synthesis in a cellular ROS- and MAPK activation-independent way.  相似文献   
92.
Anterior translocation of the pulmonary root was used as a new approach to the staged repair of Taussig-Bing anomaly with an interrupted aortic arch. It was performed to construct the right ventricle outflow tract with intraventricular baffling of the left ventricle to the aorta as the second stage operation after repair of the interrupted arch and pulmonary artery banding. This technique allows minimization of pulmonary regurgitation and has the major theoretical advantage for growth potential, which could diminish the need for reoperation.  相似文献   
93.
Inflammatory myofibroblastic tumor of the carina and the main bronchus is a rare tumor. The authors report here on a case of a 4-year-old boy with an inflammatory myofibroblastic tumor at the carina and extending to the left main bronchus. He presented with fever and a cough of 2 months' duration. Preoperative assessment of the tumor revealed an intraluminal round mass arising from the carina and extending into the left main bronchus, and this caused near-total obstruction of the left main bronchus and the subsequent total collapse of the entire left lung. The complete resection of the mass with carinal reconstruction was successful. The tumor was a round mass measuring 1.5 × 1 cm. It had characteristic features of an inflammatory myofibroblastic tumor, namely, the proliferation of spindle-shaped fibroblasts and myofibroblasts.  相似文献   
94.
Lim SW  Li C  Ahn KO  Kim J  Moon IS  Ahn C  Lee JR  Yang CW 《Transplantation》2005,80(5):691-699
BACKGROUND: The toll-like receptor (TLR) is stimulated by not only pathogen-associated molecular patterns but also endogenous TLR ligands provided by injured cells. The influence of cyclosporine A (CsA)-induced renal injury on TLR expression and subsequent signaling pathway was evaluated. METHODS: Induction of chronic CsA nephropathy was made by administering CsA (15 mg/kg/day) for 28 days in rats. The TLR2 and TLR4 mRNA and protein expression, TLR-signaling pathway (MYD88, NF-kappaB and AP-1), putative TLR ligand (heat shock protein 70 [HSP70]), and maturation of dendritic cells were evaluated in CsA-treated rat kidneys. RESULTS: Long-term CsA treatment upregulated TLR2 and TLR4 mRNA and protein expression on renal tubular cells, and these were accompanied by increased MYD88, NF-kappaB and AP-1 expression. Putative TLR ligand (HSP70) was also significantly increased in CsA-treated rat kidney compared with vehicle-treated rat kidney. CsA-treatment increased expression of TNF-alpha mRNA, the number of dendritic cells, and expression of MHC class II antigen. Double-labeling of markers of dendritic cells and MHC class II antigen revealed that matured dendritic cells increased in CsA-treated rat kidney. CONCLUSIONS: CsA-induced renal injury stimulates components of innate immunity, and this finding suggests close association between CsA-induced renal injury and activation of innate immunity.  相似文献   
95.
Risk factors for adjacent segment disease after lumbar fusion   总被引:1,自引:0,他引:1  
The incidence of adjacent segment problems after lumbar fusion has been found to vary, and risk factors for these problems have not been precisely verified, especially based on structural changes determined by magnetic resonance imaging. The purpose of this retrospective clinical study was to describe the incidence and clinical features of adjacent segment disease (ASD) after lumbar fusion and to determine its risk factors. We assessed the incidence of ASD in patients who underwent lumbar or lumbosacral fusions for degenerative conditions between August 1995 and March 2006 with at least a 1-year follow-up. Patients less than 35 years of age at the index spinal fusion, patients with uninstrumented fusion, and patients who had not achieved successful union were excluded. Of the 1069 patients who underwent fusions, 28 (2.62%) needed secondary operations because of ASD and were included in this study. In order to identify the risk factors, we matched a disease group and a control group. The disease group consisted of 26 of the 28 patients with ASD, excluding the 2 patients for whom we did not have initial MRI data. Each patient in the disease group was matched by age, sex, fusion level and follow-up period with a control patient. The assumed risk factors included disc and facet degeneration, instability, listhesis, rotational deformity, and disc wedging. The mean age of the 28 patients with ASD requiring surgical treatment was 58.4 years, which did not differ significantly from that of the population in which ASD did not develop (58.2 years, p = 0.894). Of the 21 patients who underwent floating fusion, only 1 developed distal ASD. Facet degeneration was a significant risk factor (p < 0.01) on logistic regression analysis. The incidence of distal ASD was much lower than that of proximal ASD. Pre-existing facet degeneration may be associated with a high risk of adjacent segment problems following lumbar fusion procedures.  相似文献   
96.

Background

We wanted to investigate the results of surgical treatment and analyze the factors that have an influence on the neurologic symptoms and prognosis of spinal intradural extramedullary (IDEM) tumors.

Methods

The spinal IDEM tumor patients (11 cases) who had been treated by surgical excision and who were followed up more than 1 year were retrospectively analyzed. Pain was evaluated by the visual analogue scale (VAS) and the neurologic function was assessed by Nurick''s grade. The pathological diagnosis, the preoperative symptom duration, the tumor location on the sagittal and axial planes and the percentage of tumor occupying the intradural space were investigated. In addition, all these factors were analyzed in relation to the degree of the preoperative symptoms and the prognosis. On the last follow-up, the MRI was checked to evaluate whether or not the tumor had recurred.

Results

The most common diagnosis was schwannomas (73%), followed by meningiomas (18%). The percentage of tumor occupying the intradural space was 82.9 ± 9.4%. The VAS score was reduced in all cases from 8.0 ± 1.2 to 1.2 ± 0.8 (p = 0.003) and the Nurick''s grade was improved in all cases from 3.0 ± 1.3 to 1.0 ± 0.0 (p = 0.005). The preoperative symptoms were correlated with only the percentage of tumor occupying the intradural space (VAS; r2 = 0.75, p = 0.010, Nurick''s grade; r2 = 0.69, p = 0.019). One case of schwannoma recurred.

Conclusions

The degree of neurologic symptoms was correlated with the percentage of tumor occupying the intradural space. All the tumors were able to be excised through the posterior approach. The postoperative neurologic recovery was excellent in all the cases regardless of any condition. Therefore, aggressive surgical excision is recommended even for cases with a long duration of symptoms or a severe neurologic deficit.  相似文献   
97.
Summary

The induction and rejoining of X-ray-induced double-strand breaks (dsb) in chromosomal DNA has been difficult to measure. We have developed a pulsed-field gel electrophoresis (PFGE)-based system for directly estimating DNA sizes between 0·2 and 10 million base pairs. With this system we can estimate average DNA sizes from randomly broken chromosomes by measuring the approximate molecular weight of the maximum DNA concentration. In practice this is effective where the average is between 1 and 4 million bp allowing both shoulders of the distribution to be observed. This corresponds to a dose range of 20–80 Gy. Qualitative differences from non-irradiated DNA can be observed down to about 5 Gy. We have confirmed the dose response by utilizing methotrexate-resistant mouse cells containing circular double-minute (dm) chromosomes of 1, 1·5, and 3 million bp. The kinetics of dsb rejoining from doses of 50 and 5 Gy was investigated: 50 Gy reduced the chromosomal DNA to an average size of approximately 1 million bp, followed by a constant repair rate of 44 dsb per minute per cell for 3 h (assuming a total genome size of 10 million bp).  相似文献   
98.
PurposeThe purpose of this study was to investigate the anticancer effects of combined RNA interference (RNAi) of the adenine nucleotide translocase-2 (ANT2) gene and ganciclovir (GCV) therapy for treatment of hepatocellular carcinoma cells (Huh 7) in an animal model.MethodsThe Huh 7/NTG stable cell line was established by transfection of a vector with the human sodium iodide symporter (hNIS), HSV1-sr39 thymidine kinase (tk), and enhanced green florescent protein (EGFP) fusion gene into Huh 7 cells. mRNA expressions of these genes were evaluated by RT-PCR analysis. The functions of hNIS and HSV1-sr39tk were verified with 125I uptake and 3H-penciclovir (PCV) uptake tests. EGFP and hNIS expression was confirmed with confocal microscopy after immunocytochemical staining. We treated the tumor cells with ANT2 shRNA or GCV or both ANT2 shRNA and GCV and treated the in vivo mouse model with a Huh 7/NTG tumor xenograft. The therapeutic effects of the in vivo study were assessed with caliper measurements and gamma camera imaging using 99mTc-pertechnetate.ResultsHuh 7/NTG cells showed a cell number-dependent increase in 125I uptake and a 24-fold higher 3H-PCV uptake compared to parent Huh 7 cells. Huh 7/NTG cells transfected with ANT2 shRNA had lower ANT2 mRNA expression and more impaired proliferation activity than cells transfected with scramble shRNA. Proliferation of Huh 7/NTG cells was also inhibited by GCV treatment. Combined GCV and ANT2 shRNA therapy further inhibited cell proliferation in the in vitro study. The combined therapy with GCV and ANT2 shRNA showed a further decrease in tumor growth in the mouse model.ConclusionsOur results suggest that the combined RNA interference with ANT2 and GCV therapy inhibited hepatocellular carcinoma cell proliferation more than single GCV therapy or ANT2 shRNA therapy in vitro and in vivo. Therefore it could be applied treating incurable hepatocellular carcinoma.  相似文献   
99.
A wide spectrum of pulmonary complications occurs in patients with pneumoconiosis. Those complications include chronic obstructive pulmonary disease, hemoptysis, pneumothorax, pleural disease, tuberculosis, autoimmune disease, anthracofibrosis, chronic interstitial pneumonia, and malignancy. Generally, imaging workup starts with plain chest radiography. However, sometimes, plain radiography has limited role in the diagnosis of pulmonary complications of pneumoconiosis because of overlapping pneumoconiotic infiltration. Computed tomography (CT), ultrasonography (US), and magnetic resonance imaging (MRI) are potentially helpful for the detection of pulmonary complications in patients with pneumoconiosis. CT, with its excellent contrast resolution, is more sensitive and specific method than plain radiograph in the evaluation of pulmonary abnormalities. CT is useful in detecting lung parenchymal abnormalities caused by infection, anthracofibrosis, and chronic interstitial pneumonia. Also, CT is valuable in distinguishing localized pneumothorax from bullae and aiding the identification of multiloculated effusions. US can be used in detection of complicated pleural effusions and guidance of the thoracentesis procedure. MRI is useful for differentiating between progressive massive fibrosis and lung cancer.  相似文献   
100.
PURPOSE: We evaluate terazosin therapy for chronic prostatitis/chronic pelvic pain syndrome. MATERIALS AND METHODS: The study included 100, 20 to-50-year-old subjects who met the consensus criteria for chronic prostatitis/chronic pelvic pain syndrome and had not received previous alpha-blockers. Subjects were randomized to receive terazosin with dose escalation from 1 to 5 mg. daily or placebo for 14 weeks. The primary criterion for response was scoring 2 or less ("delighted-to-mostly satisfied") on the National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) quality of life item. The secondary criterion for response was greater than 50% reduction in NIH-CPSI pain score at 14 weeks. Other outcomes included total and NIH-CPSI domain scores, International Prostate Symptom Score, peak urinary flow rate, post-void residual urine and adverse effects. RESULTS: Using the primary criterion 24 of 43 evaluable subjects (56%) responded in the terazosin group compared to 14 of 43 (36%) in the placebo group (p = 0.03). Using the secondary criterion 26 of 43 subjects (60%) responded in the terazosin group compared to 16 of 43 (37%) in the placebo group (p = 0.03). The terazosin group had greater reductions (p <0.05) in NIH-CPSI total score, individual domain scores and International Prostate Symptom Score than the placebo group. There was no difference in peak urinary flow rate or post-void residual. In the terazosin group 18 patients (42%) had side effects compared to 9 (21%) in the placebo group (p = 0.04). CONCLUSIONS: Terazosin proved superior to placebo for patients with chronic prostatitis/chronic pelvic pain syndrome who had not received alpha-blockers previously.  相似文献   
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