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21.
BACKGROUND: Tissue factor (TF) expression is induced on macrophages and endothelial cells during the immune response. We designed an antisense (AS) phosphorothioate oligodeoxynucleotide (ODN) to specifically inhibit the expression of rat TF to study the effects of the AS ODN on renal ischemia-reperfusion injury in the rat. METHOD: AS-1 ODN for TF was delivered intravenously to inhibit the expression of TF in endothelial cells. After 8 hr, the right kidney was harvested and the left renal artery and vein were clamped. The kidney was reperfused after 90 min of ischemia, and rats were killed at 0, 1.5, 5, 12, and 24 hr after reperfusion. TF expression was analyzed by immunohistochemical staining using monoclonal antibody. RESULTS: In the untreated ischemic group, 0 of 20 rats survived beyond day 3. However, treatment with AS-1/TF led to 12 of 20 rats surviving beyond day 4. TF was detected on distal tubular epithelial cells, endothelial cells, and blood vessels but not on necrotic and proximal tubular epithelial cells. The necrotic area extended and encompassed nearly all of the ischemic kidney within 12 hr after reperfusion. The necrotic area and the grade of TF staining were more significantly reduced in the AS-1/TF-treated group than in the control group. Furthermore, fluorescein isothiocyanate-labeled AS-1/TF was significantly intense in tubular epithelial cells 8 hr after intravenous administration. CONCLUSIONS: The results indicate that AS-1/TF inhibited the ischemia-reperfusion injury of the kidney. Microcirculatory incompetence resulting from microthrombus may cause the formation and development of necrosis.  相似文献   
22.
Purpose  This study was undertaken to evaluate the changes in the radiopacity and mechanics of polymethylmethacrylate (PMMA) bone cement with the addition of barium. Materials and methods  Barium sulfate powder was added to a PMMA bone cement with an initial 10% barium concentration. The changes in radiopacity and strength were evaluated by testing cement blocks containing four barium concentrations (10%, 20%, 30%, 40%). Radiopacity was evaluated by measuring the computed tomography (CT) values of the bone cement, and strength was evaluated by compressive, three-point bending, and impact load tests. Results  CT values increased in proportion to the barium concentration. The compressive load test showed that cement with a 40% barium concentration was significantly more fragile than cement with lower barium concentrations. The three-point bending load test showed that the cement became more fragile in proportion to the barium concentration. The impact load test showed that cement with 30% and 40% barium concentrations was significantly more fragile than cement with 10% and 20% barium concentrations. Conclusion  Radiopacity is increased and strength is reduced by adding increasing concentrations of barium powder to bone cement. The results of the present study suggest that adding barium permits the radiopacity and strength of bone cement to be adjusted in clinical practice.  相似文献   
23.
Although human complement‐dependent cytotoxicity (CDC) of α1,3‐galactosyltransferase gene‐knockout (GTKO) pig cells is significantly weaker than that of wild‐type (WT) cells, successful xenotransplantation will require pigs with multiple genetic modifications. Sera from healthy humans were tested by (i) flow cytometry for binding of IgM/IgG, and (ii) CDC assay against peripheral blood mononuclear cells and porcine aortic endothelial cells from five types of pig – WT, GTKO, GTKO transgenic for H‐transferase (GTKO/HT), WT transgenic for human complement regulatory protein CD46 (CD46) and GTKO/CD46. There was significantly higher mean IgM/IgG binding to WT and CD46 cells than to GTKO, GTKO/HT, and GTKO/CD46, but no difference between GTKO, GTKO/HT, and GTKO/CD46 cells. There was significantly higher mean CDC to WT than to GTKO, GTKO/HT, CD46, and GTKO/CD46 cells, but no difference between GTKO and GTKO/HT. Lysis of GTKO/CD46 cells was significantly lower than that of GTKO or CD46 cells. CD46 expression provided partial protection against serum from a baboon sensitized to a GTKO pig heart. GTKO/CD46 cells were significantly resistant to lysis by human serum and sensitized baboon serum. In conclusion, the greatest protection from CDC was obtained by the combination of an absence of Gal expression and the presence of CD46 expression, but the expression of HT appeared to offer no advantage over GTKO. Organs from GTKO/CD46 pigs are likely to be significantly less susceptible to CDC.  相似文献   
24.
Livers transplanted across major histocompatibility complex (MHC) barriers in mice are normally accepted without recipient immune suppression. To identify the cell type that contributes to induction of such a tolerance state, we established an allogeneic mixed hepatic constituent cell-lymphocyte reaction (MHLR) assay. Hepatic constituent cells were isolated from C57BL/6 (B6) and Balb/c mice as stimulators, and splenocytes were isolated from B6 mice as responders. Irradiated hepatic constituent cells were co-cultured with fluorescent dye (CFSE)-labeled B6 splenocytes. In the allogeneic MHLR using either whole hepatic constituent cells or parenchymal hepatocytes as stimulators, a lack of T-cell proliferation was observed. Only when CD105(+) cells, which are exclusively liver sinusoidal endothelial cells (LSECs), were depleted from hepatic constituent cell stimulators, the MHLR resulted in marked proliferation of both allo-reactive CD4(+) and CD8(+) T cells. These results indicate that CD105(+) LSECs have the capacity to induce nonresponsiveness of T cells across MHC barriers.  相似文献   
25.
OBJECTIVE: The purpose of the study was to examine the oncological and functional outcomes of multimodality therapy for patients with advanced malignant maxillary sinus tumors that invaded the orbit. STUDY DESIGN: Retrospective study. METHODS: The medical records of 26 patients with orbital invasion were retrospectively analyzed. The patient group consisted of 16 men and 10 women, with a median age of 58 years. The mean follow-up period was 73 months. The most common disease was squamous cell carcinoma. Seven patients had nodal disease. All patients underwent simultaneous combined therapy consisting of conservative surgery through a sublabial incision, radiotherapy, and regional chemotherapy. Patients with nodal disease were treated with either irradiation or selective neck dissection. RESULTS: The 5- and 10-year overall survival rates were 68% and 51%, respectively. The 5- and 10-year local control rates were 66% and 51%, respectively. Overall survival rates and local control rates were significantly worse in patients with disease other than squamous cell carcinoma. Local control rates were significantly worse in patients with orbital apex disease than in patients without orbital apex disease. All 26 patients, despite orbital involvement, retained their orbital contents. Nineteen of these patients demonstrated adequate ocular function. CONCLUSIONS: Combined therapy with conservative surgery, radiotherapy, and regional chemotherapy is an effective method for local control and preservation of ocular function. However, performing orbital conservation procedure in patients with disease other than squamous cell carcinoma and with orbital apex disease must be considered carefully.  相似文献   
26.
In Japan, information on daily Japanese cedar pollen counts is made public during pollen season. If symptom severity and treatment outcome are predictable according to these pollen counts, management of seasonal allergic rhinitis may become more precise. The aims of the study were to evaluate the relationship between airborne pollen counts, symptom severity and treatment outcome in Japanese cedar pollinosis patients. In the randomized study, patients with moderate to most severe Japanese pollinosis were treated with fexofenadine (60 mg BD) or fexofenadine and nasal corticosteroids for 2 weeks. During the same period daily airborne pollen counts were measured. A total of 105 adult patients were enrolled. No difference of treatment efficacy was seen among groups. Detailed results of efficacy and safety were previously described elsewhere. In univariate analysis, the mean cumulative amount of airborne pollen exposure for 4 days prior to the study tended to affect symptom severity (P = 0.053) and the mean cumulative amount of airborne pollen during the treatment period tended to show difference among five treatment outcome categories (P = 0.066). In multivariate analysis, the mean cumulative amount of airborne pollen exposure for 4 days prior to the study was identified as the only significant factor of symptom severity (P = 0.0327) and cumulative amount of airborne pollen during the treatment period (P = 0.027) and allergic history (P = 0.027) were significant factors of treatment outcomes. No serious adverse effect was reported during the study. The amount of airborne pollen may be predictive of both symptom severity and treatment outcome.  相似文献   
27.
PURPOSE: To identify the tomographic features of the branching vascular networks in patients with polypoidal choroidal vasculopathy (PCV). METHODS: We prospectively performed third-generation optical coherence tomography (OCT) and fluorescein angiography for 44 eyes of 42 patients (mean age +/- SD, 67.1 +/- 9.1 years) with PCV. All eyes had branching vascular networks and polypoidal lesions that were confirmed by indocyanine green angiography. RESULTS: OCT showed double reflective layers that consisted of retinal pigment epithelium (RPE) and another highly reflective layer beneath the RPE ("double-layer sign") in the area of the branching network vessels in 26 (59%) of 44 eyes. The remaining 18 eyes had no double-layer sign, but 17 (94%) of 18 eyes had a slightly elevated RPE. A serous retinal detachment was present in 23 (88%) of 26 eyes with a double-layer sign, while only 1 (6%) of 18 eyes without the sign had a serous retinal detachment. CONCLUSIONS: In PCV, the double-layer sign is seen frequently in the area of the network vessels, particularly in eyes with a serous retinal detachment. The sign may reflect fluid accumulation between RPE and Bruch membrane resulting from leakage from the network of abnormal vessels.  相似文献   
28.
AIM: The relative afferent pupillary defect (RAPD) is an important clinical sign of asymmetrical retinal ganglion cell and axonal damage. Although glaucoma essentially affects bilateral eyes, a subset of patients manifests asymmetrical glaucomatous optic neuropathy (GON), which exhibits an RPAD in the more advanced eyes. However, the degree to which axonal loss occurs before an RAPD is clinically detectable has not been substantiated. The purpose of this study is to assess the relationship between the depth of a clinically detectable RAPD and the reduction ratio of retinal nerve fiber layer (RNFL) thickness in the more advanced eyes relative to that in the contralateral less advanced eyes of patients with asymmetrical GON. METHODS: Enrolled were 29 consecutive glaucoma patients with the clinically detectable RAPD. An RAPD was quantified by placing log-scaled neutral density filters over the less advanced eyes while performing the swinging flashlight test. Average RNFL thickness was determined using the Fast RNFL thickness programme of optical coherence tomography 3000. Correlation coefficient and Linear regression analyses were used in assessing the relationship between the RAPD and the ratio of RNFL thickness in the more advanced eyes relative to that in the less advanced. RESULTS: RAPD ranged from 0.6 to 2.4 log units. The log-scaled RAPD had a statistically significantly inversed correlation with the average RNFL thickness ratio (r(s) = -0.729, p<0.0001). Linear regression analysis found an equation that the average RNFL thickness ratio in the more affected eyes relative to that in the less advanced (%) = (0.827-0.169xRAPD (log units))x100 (R(2) = 0.557, p<0.0001). CONCLUSIONS: When an RAPD is clinically detected, the RNFL thickness in the more advanced eyes was in average reduced to about 73% of that in the less advanced.  相似文献   
29.
OBJECTIVE: To investigate the link between a reduction in blood pressure (BP) and daily exercise. DESIGN: Cross-sectional and longitudinal clinical intervention study with exercise education. SUBJECTS: 43 overweight Japanese men aged 32-59 years (BMI, 29.0+/-2.3 kg/m2) at baseline. Among the participants, a randomly selected 23 overweight men (BMI, 28.5+/-1.7) were further enrolled into the 10 months exercise program. MEASUREMENTS: BP was measured every week and steps per day were also recorded every day throughout the observation period. Fat distribution was evaluated by visceral fat (V) and subcutaneous fat (S) areas measured with computed tomography (CT) scanning at umbilical level, at before, 5 months and after intervention. Anthropometric parameters were also measured at same point. Aerobic exercise level, muscle strength, flexibility and calorie intake and insulin resistance (HOMA index) were investigated at before and after the study. RESULTS: In a cross sectional analysis, systolic BP (SBP) and diastolic BP (DBP) were significantly correlated with body composition. In a second longitudinal analysis, SBP was significantly reduced at 2 months and DBP was also reduced at 3 months, and almost maintained until the end of the observation period. Increasing daily walking was observed in 3 months and maintained until 10 months. Body composition, aerobic exercise level, muscle strength, flexibility and insulin resistance were significantly improved. There was positive correlation between DeltaDBP and Deltavisceral fat area (1-5, 5-10, 1-10 months). By stepwise multiple regression analysis, only Deltavisceral fat area was independently related to DeltaDBP at a significant level (1-10 months: DeltaDBP=-0.608+0.105Deltavisceral fat area, r2=0.227, P=0.0334). CONCLUSION: The present study indicated daily exercise lowers BP and visceral fat area is the critical factor for BP change.  相似文献   
30.
Inverted ductal papilloma (IDP) is one of the least common benign papillary/cystic neoplasms of the salivary duct system, being characterized histologically by florid hyperplasia of duct-type epithelial cells into a cystic lumen near the orifice with occasional endophytic growth of the surface squamous epithelium along the terminus of the affected excretory duct. Given its rarity, the exact etiology of IDP remains to be defined. We herein present the first evidence of oncogenic HRAS mutation in a case of oral IDP. This finding, together with the frequent and specific BRAF mutations in sialadenoma papilliferum reported in the recent literature, supports an active role of the MAP-kinase cascade in the pathogenesis of benign papillary neoplasms of terminal duct origin.  相似文献   
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