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Bronchiolitis obliterans syndrome (BOS) compromises lung transplant outcomes and is characterised by airway epithelial damage and fibrosis. The process whereby the normal epithelial configuration is replaced by fibroblastic scar tissue is poorly understood, but recent studies have implicated epithelial mesenchymal transition (EMT). The primary aim of this study was to assess the utility of flow cytometry in detecting and quantifying EMT in bronchial epithelial cells.
Large airway brushings were obtained at 33 bronchoscopies in 16 BOS-free and 6 BOS grade 1–3 patients at 2–120 months posttransplant. Flow cytometry was used to assess expression of the mesenchymal markers αSMA, S100A4 and ED-A FN and HLA-DR. TGF β1 and HGF were measured in Bronchoalveolar lavage (BAL). Expression of all three mesenchymal markers was increased in BOS, as was HLA-DR. BAL HGF, but not TGF β1 was increased in BOS. Longitudinal investigation of one patient revealed a 100% increase in EMT markers concurrent with a 6-fold increase in BAL TGF β1 and the diagnosis of BOS at 17 months posttransplant.
Flow cytometric evaluation of bronchial epithelium may provide a novel and rapid means to assess lung allografts at risk of BOS.  相似文献   
33.
Acute porphyria is rare in orientals. We describe a Chinese woman with recurrent generalised tonic-clonic seizures and abdominal pain. Genomic DNA studies identified a heterozygous base substitution from guanine to adenine at nucleotide position 503, resulting in substitution of arginine by histidine at position 168 of the protein (R168H). This genetic abnormality is similar to the mutation reported in Caucasians with variegate porphyria. To the best of our knowledge, this is the first report in the English literature a Chinese patient with variegate porphyria with an identifiable mutation. A brief review of porphyria is presented.  相似文献   
34.
Ultrasound guided transrectal core biopsies of the palpably abnormal prostate   总被引:11,自引:0,他引:11  
Ultrasound imaging and ultrasound guided transrectal core biopsies were performed in 251 consecutive men with abnormal prostates on digital rectal examination. A hypoechoic defect on ultrasound was identified in 227 of 251 patients (90 per cent) corresponding to the area of palpable nodularity or abnormal firmness. A mean of 6.25 biopsies were obtained per patient using a commercially available spring-loaded gun. Biopsies were positive for cancer in 165 of the 251 prostates (66 per cent). Palpable nodules more often were hypoechoic and more often contained cancer than less distinct areas of abnormal firmness on digital examination. Among the clinical stages B1, B2 and B3 nodules 70, 76 and 88 per cent, respectively, were positive for cancer, as were 100 per cent of the clinical stage C prostates. Of 77 abnormally firm, nonnodular prostates 36 per cent were positive for cancer. Random biopsy of the contralateral normal lobe in 56 men with clinical stage B1 or B2 nodules showed cancer present contralaterally in 42 and 60 per cent, respectively; 20 per cent had positive biopsies despite a contralateral isoechoic ultrasound. In 78 patients with prior digitally guided biopsies, ultrasound guided biopsies confirmed previously diagnosed cancers in 94 per cent. However, in 23 of 43 patients (53 per cent) with previous negative digitally guided biopsies, ultrasound guided biopsies made the new diagnosis of cancer. Complications, including post-biopsy fever and bleeding, occurred in 6 of 251 patients (2.4 per cent). The combination of the new spring-loaded biopsy guns and transrectal ultrasound guidance of biopsies provides the urologist with a tool that allows multiple prostate cores to be obtained safely and painlessly, reducing the sampling error and increasing the accuracy in diagnosing prostate cancer in the man with a palpable abnormality of the prostate.  相似文献   
35.
A total of 93 recipients of either HLA-identical (34) or 1-haplotype matched (59) living related donor renal transplants was assigned prospectively into immunosuppressive treatment groups on the basis of transfusion histories obtained at the initial evaluation for transplantation. Patients who received 0 to 2 third party transfusions were given no further transfusion, and received cyclosporine and prednisone immunosuppression after transplantation (cyclosporine group). Patients who received 3 or 4 third party transfusions were given additional transfusions until 5 had been received, and were managed with azathioprine and prednisone after transplantation (azathioprine group). Patients who already received 5 or more third party transfusions had no additional transfusions and were assigned to the azathioprine group. No patient had a positive crossmatch to the potential donor after initial evaluation and confirmation of a negative crossmatch. The number of rejection episodes per patient after transplantation was significantly higher in the azathioprine group for HLA-identical (p equals 0.001) and 1-haplotype (p equals 0.003) recipients. One-year patient survival rats for the HLA-identical cyclosporine and azathioprine groups were 100 and 94 per cent, respectively, with respective 1-year allograft survivals of 100 and 89 per cent in the 2 groups. In the 1-haplotype group 1-year patient survival rates were 95 and 94 per cent for the cyclosporine and azathioprine groups, respectively; allograft survival was 81 per cent for the cyclosporine group and 91 per cent for the azathioprine group. None of the observed differences in graft or patient survival between the 2 groups was statistically significant. Deliberate third party transfusions with conventional immunosuppression and cyclosporine immunosuppression are effective methods to treat recipients of living related donor renal transplants.  相似文献   
36.
To define an optimal regimen for mobilizing and collecting peripheral blood progenitor cells (PBPC) for use in allogeneic transplantation, we evaluated the kinetics of mobilization by filgrastim (recombinant met- human granulocyte colony-stimulating factor [r-metHuG-CSF]) in normal volunteers. Filgrastim was injected subcutaneously for up to 10 days at a dose of 3 (n = 10), 5 (n = 5), or 10 micrograms/kg/d (n = 15). A subset of volunteers from each dose cohort underwent a 7L leukapheresis on study day 6 (after 5 days of filgrastim). Granulocyte-macrophage colony-forming cell (GM-CFC) numbers in the blood were maximal after 5 days of filgrastim; a broader peak was evident for CD34+ cells between days 4 and 6. The 95% confidence intervals (CI) for mean number of PBPC per milliliter of blood in the three dose cohorts overlapped on each study day. However, on the peak day, CD34+ cells were significantly higher in the 10 micrograms/kg/d cohort than in a pool of the 3 and 5 micrograms/kg/d cohorts. Mobilization was not significantly influenced by volunteer age or sex. Leukapheresis products obtained at the 10 micrograms/kg/d dose level contained a median GM-CFC number of 93 x 10(4)/kg (range, 50 x 10(4)/kg to 172 x 10(4)/kg). Collections from volunteers receiving lower doses of filgrastim contained a median GM- CFC number of 36 x 10(4)/kg (range, 5 x 10(4)/kg to 204 x 10(4)/kg). The measurement of CD34+ cells per milliliter of blood on the day of leukapheresis predicted the total yield of PBPC in the leukapheresis product (r = .87, P < .0001). Assuming a minimum GM-CFC requirement of 50 x 10(4)/kg (based on our experience with autologous PBPC transplantation), all seven leukapheresis products obtained at the 10 micrograms/kg/d dose level were potentially sufficient for allogeneic transplantation purposes. We conclude that in normal donors, filgrastim 10 micrograms/kg/d for 5 days with a single leukapheresis on the following day is a highly effective regimen for PBPC mobilization and collection. Further studies are required to determine whether PBPC collected with this regimen reliably produce rapid and sustained engraftment in allogeneic recipients.  相似文献   
37.
BACKGROUND: To estimate the effect of dietary intake of lutein and zeaxanthin (L/Z) and fats on the progression of age-related macular degeneration (AMD). METHODS: Two hundred and fifty-four subjects identified with early age-related macular degeneration (AMD) were re-examined to determine 7-year AMD progression. Intakes of L/Z and fatty acids were estimated from food frequency questionnaires. Progression was defined by 3 different definitions, 2 quantitative and 1 qualitative, which varied in the stringency of the change required for the AMD to be deemed to have progressed. Covariates included age, smoking, AMD family history, source study, and follow-up duration. RESULTS: Energy-adjusted L/Z intake as a continuous variable was associated with AMD progression in the worse affected eye when defined by the most stringent criterion (odds ratio [OR] = 2.65, 95% confidence interval [CI] 1.13-6.22, p = 0.02). Similar associations were observed for the 2 other progression definitions (p = 0.18 and p = 0.13). Energy-adjusted omega-3 fatty acid intake modelled as a quintile median was associated with AMD progression only in the side-by-side assessment (OR = 2.56, 95% CI 1.11-5.91, p = 0.03), with borderline significance in the other 2 definitions (p = 0.05 and p = 0.08). No association of AMD progression was observed with the intake of either total fat or other subgroups: saturated, polyunsaturated, or monounsaturated fats; trans fatty acids; or omega-6 fatty acids. INTERPRETATION: The findings of the study are counterintuitive, suggesting that increased intakes of dietary L/Z and omega-3 fatty acids are associated with progression of AMD. These results may indicate that too much of a good thing might be harmful. It is possible that in this study participants adopted a more healthy diet, having been aware of their AMD status at the beginning of the study. This healthy diet was then reflected in the dietary questionnaire completed at the end of study. However, this explanation may not adequately explain why those whose AMD had progressed, on the basis of fundus signs and not symptoms such as visual acuity decline, adopted a healthier lifestyle more aggressively than those without progression.  相似文献   
38.
Eighteen highly exposed but persistently seronegative (HEPS) women (HW) and their human immunodeficiency virus (HIV) type 1-seropositive male partners were studied for HIV-specific T cells and other host factors. Circulating HIV-specific T cells were measured by interferon-gamma enzyme-linked immunospot assays, using recombinant vaccinia virus vectors expressing HIV proteins. Nine (50%) of the HW and all HIV-seropositive persons had HIV-specific T cell responses. Only 2 (22%) of the HEPS responders recognized Env, compared with 94% of HIV-seropositive persons. A high percentage (75%) of the HW with HIV-specific T cell responses reported recent HIV exposure. Remarkably, however, long-lived HIV-specific T cells were detected in 2 HW who had an extended period (>3.9 years) of no HIV exposure. These findings have important implications for HIV vaccine design.  相似文献   
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