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81.
Patients with germinal center B cell-like (GCB) and non-GCB diffuse large B cell lymphomas (DLBCL) receiving first line therapy have distinct prognosis. We explored the differences in outcome following salvage autologous hematopoietic stem cell (HSC) transplantation between patients with GCB and non-GCB DLBCL. Forty-four patients with relapsed and 15 patients with primary refractory chemosensitive disease undergoing BEAM (BCNU [carmustine], etoposide, cytarabine, melphalan) conditioning and autologous HSC were included. Immunohistochemical analysis was performed for CD10, BCL-6, MUM1 (allowing classification into GCB and non-GCB-like DLBCL) and BCL-2. Median follow-up of survivors was 25 months; median age at the time of transplantation was 60 years (range 17–77). Thirty-two patients (54%) were classified as having GCB and 27 (46%) as having non-GCB-like DLBCL. Patients with GCB and non-GCB DLBCL did not differ in the risk of progression after HSC transplant ( P  = 0·78) or overall survival ( P  = 0·48). In multivariate analysis, only time to progression after initial treatment impacted overall survival. We conclude that patients with relapsed or primary refractory chemosensitive GCB and non-GCB-like DLBCL derive similar benefit from autologous HSC transplant.  相似文献   
82.
3 new cases of dermatomyositis associated with diffuse interstitial pulmonary fibrosis and, more exceptionally, with Sj?gren's syndrome are reported. The pulmonary fibrosis observed in patients with dermatomyositis differs from that found in other connective tissue diseases in that it follows a more acute course and may respond to corticosteroids. Thus, in 2 of these patients treated with corticosteroids (combined in 1 case with cyclophosphamide) the high percentage of lymphocytes and polymorphonuclears in the broncho-alveolar lavage fluid, which reflects alveolitis activity, was reduced and the pulmonary fibrosis was cured in one patient and stabilized in the other.  相似文献   
83.
Gastrointestinal dysfunction in patients with cirrhosis may contribute to complications such as malnutrition and spontaneous bacterial peritonitis. To determine whether cirrhotic patients with ascites have altered intestinal function, we compared intestinal permeability and absorption in patients with liver disease and normal subjects. Intestinal permeability and absorption were investigated in 66 cirrhotic patients (48 with ascites, 18 without ascites) and 74 healthy control subjects. Timed recovery of 3-O-methyl-D-glucose, D-xylose, L-rhamnose, and lactulose in urine following oral administration was measured in order to assess active and passive carrier-mediated, and nonmediated, absorptive capacity, as well as intestinal large-pore/small-pore (lactulose/rhamnose) permeability. Test sugars were measured by quantitative thin-layer chromatography and results are expressed as a percentage of test dose recovered in a 5-h urine collection. Sugar excretion ratios relating to small intestinal permeability (lactulose/rhamnose) and absorption (rhamnose/3-O-methyl-D-glucose) were calculated to avoid the effects of nonmucosal factors such as renal clearance, portal hypertension, and ascites on the recovery of sugar probes in urine. Compared with normal subjects, the mean lactulose/rhamnose permeability ratio in cirrhotic patients with ascites was significantly higher (0.058 vs. 0.037, P < 0.001) but not in cirrhotic patients without ascites (0.041 vs. 0.037). Cirrhotic patients with ascites had significantly lower mean recoveries of 3-O-methyl-D-glucose (23.0 vs. 49.1%; P < 0.001), D-xylose (18.8 vs. 34.5%; P < 0.001), L-rhamnose (4.0 vs. 9.1%; P < 0.001), and lactulose (0.202 vs. 0.337%; P < 0.001) than normal subjects. However, the mean rhamnose/3-O-methyl-D-glucose ratio was the same in cirrhotic patients with ascites as normal subjects (0.189 vs. 0.189), indicating that the reduction in probe recovery was due to nonmucosal factors. Compared with normal subjects, cirrhotic patients with ascites have abnormal intestinal permeability, measured by urinary lactulose/rhamnose excretion, and normal small intestinal absorption, assessed by the urinary rhamnose/3-O-methyl-D-glucose ratio. Low urine recovery of sugar probes found in cirrhotic patients appears to be the result of nonintestinal factors affecting clearance rather than reduced intestinal absorption.  相似文献   
84.
Summary A 40-year-old man presented with peritonitis. Diagnosis of phlegmonous gastritis was made by laparotomy. Conservative treatment combined with antibiotics was successful. Multiple endoscopies with biopsies illustrate the natural history of this disease. The patient developed HIV-1 seroconversion during hospital stay. Prompt diagnosis and treatment may improve the prognosis of this often lethal disease.  相似文献   
85.
Summary In order to characterize the antigenic determinants of Leishmania aethiopica , we have analysed by immunoblotting the antibody reactivity of leishmaniasis patients with either the localized (LCL) or diffuse (DCL) clinical forms of disease. In this study we have compared the reactivity of antibodies from eight LCL and DCL patients to parasites isolated from each individual, or the parasite isolates of the other LCL and DCL patients studied. The immunoblot profiles of antibodies from LCL patients differed from the antibody profiles of DCL patients. Serum antibodies from LCL patients showed limited recognition of somatic antigens of < Mr 50000 which were recognized by antibodies present in DCL patients. A direct comparison of individual LCL and DCL patient derived promastigotes determined that the lack of antibody to these antigens in LCL patients was not due to the differential expression of these determinants by the LCL and DCL derived promastigotes. The results of this study suggest that although either LCL or DCL derived promastigotes express a wide variety of antigenic moieties which are potentially reactive with antibodies, only a subset of antibodies against these specificities develop in any individual patient, during active infection.  相似文献   
86.
There is controversy in the literature as to whether anaplastic large-cell lymphoma of B-cell phenotype is related to the t(2;5)-positive T- or 'null' cell lymphoma of the same morphology. We report a study of 24 lymphomas with morphological features of anaplastic large-cell lymphoma which expressed one or more B-cell markers and lacked T-lineage markers. Clinical features were more in keeping with large B-cell lymphoma than with classical t(2;5)-positive anaplastic large-cell lymphoma, and immunostaining for anaplastic lymphoma kinase (ALK) protein provided no evidence for the (2;5) translocation (or one of its variants). The staining patterns for CD20 and CD79 were typical of diffuse large B-cell lymphoma, CD30 expression was variable, and most cases (15/22) lacked epithelial membrane antigen (EMA). These findings support the view that 'B-cell anaplastic large-cell lymphoma' is unrelated to t(2;5)-positive (ALK-positive) lymphoma, and that it represents a morphological pattern occasionally encountered among diffuse large B-cell lymphomas. By the same reasoning, most tumours diagnosed as 'ALK-negative anaplastic large-cell lymphoma of T-cell or null phenotype' probably belong to the spectrum of peripheral T-cell lymphomas.  相似文献   
87.
BackgroundAn increase in fractional flow reserve (FFR) after percutaneous coronary intervention (PCI) is associated with improvement in angina. Coronary artery disease (CAD) patterns (focal vs diffuse) influence the FFR change after stenting and may predict angina relief.ObjectivesThe aim of this study was to investigate the differential improvement in patient-reported outcomes after PCI in focal and diffuse CAD as defined by the pullback pressure gradient (PPG).MethodsThis is a subanalysis of the TARGET-FFR (Trial of Angiography vs. pressure-Ratio-Guided Enhancement Techniques–Fractional Flow Reserve) randomized clinical trial. The 7-item Seattle Angina Questionnaire (SAQ-7) was administered at baseline and 3 months after PCI. The PPG index was calculated from manual pre-PCI FFR pullbacks. The median PPG value was used to define focal and diffuse CAD. Residual angina was defined as an SAQ-7 score <100.ResultsA total of 103 patients were analyzed. There were no differences in the baseline characteristics between patients with focal and diffuse CAD. Focal disease had larger increases in FFR after PCI than patients with diffuse disease (0.30 ± 0.14 vs 0.19 ± 0.12; P < 0.001). Patients with focal disease who underwent PCI for focal CAD had significantly higher SAQ-7 summary scores at follow-up than those with diffuse CAD (87.1 ± 20.3 vs 75.6 ± 24.4; mean difference = 11.5 [95% CI: 2.8-20.3]; P = 0.01). After PCI, residual angina was present in 39.8% but was significantly less in those with treated focal CAD (27.5% vs 51.9%; P = 0.020).ConclusionsResidual angina after PCI was almost twice as common in patients with a low PPG (diffuse disease), whereas patients with a high PPG (focal disease) reported greater improvement in angina and quality of life. The baseline pattern of CAD can predict the likelihood of angina relief. (Trial of Angiography vs. pressure-Ratio-Guided Enhancement Techniques–Fractional Flow Reserve [TARGET-FFR]; NCT03259815)  相似文献   
88.
Acute complicated diverticulitis, particularly with colon perforation, is a rare but serious condition in transplant recipients with high morbidity and mortality. Neither acute diverticulitis nor colon perforation has been reported in young heart-lung grafted patients. A case of subclinical peritonitis due to perforated acute sigmoid diverticulitis 14 years after heart-lung transplantation is reported. A 26-year-old woman, who received heart-lung transplantation 14 years ago, presented with vague abdominal pain. Physical examination was normal. Blood tests revealed leukocytosis. Abdominal X-ray showed air-fluid levels while CT demonstrated peritonitis due to perforated sigmoid diverticulitis. Sigmoidectomy and end-colostomy (Hartmann's procedure) were performed. Histopathology confirmed perforated acute sigmoid diverticulitis. The patient was discharged on the 8th postoperative day after an uneventful postoperative course. This is the first report of acute diverticulitis resulting in colon perforation in a young heart-lung transplanted patient. Clinical presentation, even in peritonitis, may be atypical due to the masking effects of immunosuppression. A high index of suspicion, urgent aggressive diagnostic investigation of even vague abdominal symptoms, adjustment of immunosuppression, broad-spectrum antibiotics, and immediate surgical treatment are critical. Moreover, strategies to reduce the risk of this complication should be implemented. Pretransplantation colon screening, prophylactic pretransplantation sigmoid resection in patients with diverticulosis, and elective surgical intervention in patients with nonoperatively treated acute diverticulitis after transplantation deserve consideration and further studies.  相似文献   
89.
BackgroundDiffuse large B‐cell lymphoma (DLBCL) is the most common category of non‐Hodgkin lymphoma (NHL). However, the underlying molecular mechanism of DLBCL remains unclear.MethodsReal‐time PCR and Western blot analysis were performed to assess the expression of ubiquitin‐specific peptidase 21 (USP21) or enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2). CCK8 assay and cell death staining were carried out to examine the role of USP21 in cell proliferation and cell death, respectively.ResultsWe found that the deubiquitinase USP21 was highly expressed in the DLBCL lymphoid tissue. The expression of USP21 promoted DLBCL cell proliferation, while it had no obvious effect on cell death. In addition, we found that USP21 regulated cell proliferation via cysteine 221, the catalytic site of USP21. Furthermore, we identified that USP21 could stabilize EZH2, a protein required for germinal center formation and lymphoma formation.ConclusionThe deubiquitinase USP21 promotes cell proliferation by maintaining the EZH2 protein level in DLBCL.  相似文献   
90.
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