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31.
High pre-treatment serum hepatitis B virus titre predicts failure of lamivudine prophylaxis and graft re-infection after liver transplantation 总被引:16,自引:0,他引:16
Mutimer D Pillay D Dragon E Tang H Ahmed M O'Donnell K Shaw J Burroughs N Rand D Cane P Martin B Buchan S Boxall E Barmat S Gutekunst K McMaster P Elias E 《Journal of hepatology》1999,30(4):715-721
BACKGROUND/AIMS: Orthotopic liver transplantation has an established role for the treatment of patients with chronic liver failure secondary to hepatitis B virus (HBV) infection. Unfortunately, recurrent infection of the graft can be associated with aggressive disease, and with diminished graft and patient survival. Currently, the role of nucleoside analogues for prevention of graft re-infection is being evaluated. Preliminary results are encouraging, but treatment failure has been associated with emergence of drug-resistant virus. METHODS: We have studied ten consecutive patients who received lamivudine prophylaxis for prevention of HBV graft reinfection. Sequential sera, collected prelamivudine then during treatment before and after liver transplantation, were examined. Conventional serological markers were measured, as were serum viral DNA levels with a sensitive quantitative polymerase chain reaction assay. RESULTS: Lamivudine treatment effected a reduction in serum HBV levels, but six patients still had measurable viral DNA at the time of transplantation. Five patients developed graft re-infection with lamivudine-resistant virus. Resistant virus emerged 8 to 15 months post-transplant. The likelihood of emergence of resistant virus was related to the pre-treatment serum HBV titre. Persistent serum viral DNA positivity and evidence of graft re-infection during the early post-transplant period did not predict the subsequent emergence of resistant virus. CONCLUSIONS: Our observations suggest that the resistant species may be present in the viral quasispecies in the serum and liver of patients with high-level replication prior to lamivudine exposure. The resistant species can persist during lamivudine treatment prior to transplantation, and emerge following transplantation. These observations suggest strategies which might prevent the emergence of drug-resistant species, and imply that graft re-infection may be a preventable phenomenon. 相似文献
32.
Fabrizio Cardin MD Massimo Graffeo MD P. Aiden McCormick MRCP Neil McIntyre FRCP Dr. Andrew Burroughs FRCP 《Digestive diseases and sciences》1992,37(3):335-339
The etiology of extrahepatic venous obstruction (EHVO) is unknown in 50% of cases. Recently the presence of a latent myeloproliferative disorder has been reported in adults with idiopathic EHVO. We evaluated the course of these patients to establish if any putative latent myeloproliferative disorder influenced the clinical course compared to those with a known cause. Among 132 EHVO patients, 78 (59%) had a known etiology, 7 (5%) with an overt myeloproliferative disorder. The idiopathic group had 54 patients; 24 (13 men, 11 women) were diagnosed after 15 years of age, (median 38 years, range 17–70) with a median follow up of 96 months (19–372). Only 2 (8%) developed an overt myeloproliferative disorder. These 24 had a similar pattern of bleeding and onset of ascites as those with known cause. In EHVO failure to diagnose a latent myeloproliferative disorder does not influence the course of variceal bleeding, and thus has little prognostic significance.Supported by R Farini Foundation for Gastroenterology Research. 相似文献
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34.
Jonathan Bryant-Genevier Carol Y. Rao Barbara Lopes-Cardozo Ahoua Kone Charles Rose Isabel Thomas Diana Orquiola Ruth Lynfield Dhara Shah Lori Freeman Scott Becker Amber Williams Deborah W. Gould Hope Tiesman Geremy Lloyd Laura Hill Ramona Byrkit 《MMWR. Morbidity and mortality weekly report》2021,70(26):947
35.
Gabrielle C Baxter Andrew J Patterson Ramona Woitek Iris Allajbeu Martin J Graves Fiona Gilbert 《The British journal of radiology》2021,94(1119)
Objective:To compare diffusion-weighted images (DWI) acquired using single-shot echo-planar imaging (ss-EPI) and multiplexed sensitivity encoding (MUSE) in breast cancer.Methods20 females with pathologically confirmed breast cancer (age 51 ± 12 years) were imaged with ss-EPI-DWI and MUSE-DWI. ADC, normalised ADC (nADC), blur and distortion metrics and qualitative image quality scores were compared. The Crété-Roffet and Mattes mutual information metrics were used to evaluate blurring and distortion, respectively. In a breast phantom, six permutations of MUSE-DWI with varying parallel acceleration factor and number of shots were compared. Differences in ADC and nADC were compared using the coefficient of variation in the phantom and a paired t-test in patients. Differences in blur, distortion and qualitative metrics were analysed using a Wilcoxon signed-rank test.Results:There was a low coefficient of variation (<2%) in ADC between ss-EPI-DWI and all MUSE-DWI permutations acquired using the phantom. 22 malignant and three benign lesions were identified in 20 patients. ADC values measured using MUSE were significantly lower compared to ss-EPI for malignant but not benign lesions (p < 0.001, p = 0.21). nADC values were not significantly different (p = 0.62, p = 0.28). Blurring and distortion improved with number of shots and acceleration factor, and significantly improved with MUSE in patients (p < 0.001, p = 0.002). Qualitatively, image quality improved using MUSE.Conclusion:MUSE improves the image quality of breast DWI compared to ss-EPI.Advances in knowledge:MUSE-DWI has superior image quality and reduced blurring and distortion compared to ss-EPI-DWI in breast cancer. 相似文献
36.
37.
Giorgio Minoli M.D. Vittorio Terruzzi M.D. Gianni Imperiali M.D. Guido Frigerio M.D. Enrico Colombo M.D. Umberto Comin M.D. Giuseppe Corsini M.D. Marcello Curzio M.D. Alberto Prada M.D. Francesco Rocca M.D. Renato Venturelli M.D. Andrew Kenneth Burroughs M.D. 《The American journal of gastroenterology》1994,89(1):72-78
Objective : To evaluate if tbere was periodicity in the manifestations of gastrointestinal bleeding (hemateme-sis and melena). Method : This is a multicenter prospective study carried out in the Endoscopy Units of eight hospitals. At the time of the emergency endoscopy, the following data were collected: age, sex, endoscopic diagnosis, solar hour of the first hematemesis (vomiting of bright red or tarry black material) and of the first melena (black or bloody soft stools), and any drugs taken during the week before the bleeding episode, regardless of the dose. Results : 806 patients were studied. Bleeding was from peptic ulcer in 405 patients (50%), from esophageal varices in 197 (24%), and from other sources in the remainder. Analysis using single cosinor statistics showed a nonrandom distribution in bleeding from peptic ulcer, whether presenting first with hematemesis (p = 0.02) or melena (p = 0.03). There were two peaks at 6:45 AM and 6:45 PM for hemate-mesis and at 7:25 AM and 7:25 PM for melena, representing a biphasic diurnal (ultradian) rhythm. Conclusions : This study shows that bleeding due to peptic ulcer has a biphasic diurnal periodicity. 1 his has potential importance for the pathogenesis of bleeding, for the management of gastrointestinal hemorrhage and the administration of drugs known to cause peptic ulcer bleeding. 相似文献
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Burroughs LM Woolfrey AE Storer BE Deeg HJ Flowers ME Martin PJ Carpenter PA Doney K Appelbaum FR Sanders JE Storb R 《British journal of haematology》2012,158(1):120-128
Allogeneic marrow transplantation offers curative therapy for children with severe aplastic anaemia (SAA). We report the outcomes of 148 children with SAA who received human leucocyte antigen (HLA)-matched related marrow grafts between 1971 and 2010. Patients were divided into three groups, reflecting changes in conditioning and graft-versus-host disease (GVHD) prophylaxis regimens that occurred over time. Patients in Group 1 were conditioned with cyclophosphamide (CY; 200 mg/kg) followed by 'long' (102 d) methotrexate (MTX). Patients in Groups 2 and 3 received CY alone (Group 2) or combined with anti-thymocyte globulin (Group 3) followed by 'short' (days 1, 3, 6, and 11) MTX and ciclosporin (until day 180). With a median follow-up of 25 years, the 5-year survivals were 66%, 95%, and 100% for Groups 1, 2, and 3, respectively (overall P < 0·0001). The 3-year estimates of graft rejection were 22%, 32%, and 7%, respectively. The probabilities of grades III-IV acute and 2-year chronic GVHD were 15%, 0%, and 3%, and 21%, 21%, and 10%, respectively. Advances in preparative and GVHD prophylaxis regimens, and supportive care during the past 40 years have led to improved outcomes for children with SAA. These results confirm the use of allogeneic marrow transplantation for children with SAA who have HLA-matched related donors. 相似文献