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61.
Trisomy 12 defines a group of CLL with atypical morphology: correlation between cytogenetic, clinical and laboratory features in 544 patients 总被引:7,自引:0,他引:7
E. Matutes D. Oscier J. Garcia-Marco J. Ellis A. Copplestone R. Gillingham T. Hamblin D. Lens G. J. Swansbury & D. Catovsky 《British journal of haematology》1996,92(2):382-388
We have analysed the clinical and laboratory features in 544 patients with chronic lymphocytic leukaemia (CLL) with available cytogenetics and fluorescence in-situ hybridization (FISH) analysis for trisomy 12 in half of them, to examine the correlation between chromosome abnormalities and clinical or laboratory parameters. Five chromosome groups were defined: (1) trisomy 12 (18%), detected as the sole abnormality or associated with other changes; (2) del(13)(q12–14) (7%); (3) other abnormal karyotypes (20%); (4) normal karyotype (41%); and (5) no divisions (14%). There were no differences in the age distribution between the five groups. Clinical stages (Binet) were: A (74%), B (12%) and C (14%). Stage A was common in cases with del(13q)(82%), normal (84%) and other abnormal karyotypes (74%), whereas it was less common in trisomy 12 cases (64%) and those with no divisions (48%). Typical CLL morphology was found in 83% of cases; 10% had more than 10% prolymphocytes (CLL/PL) and 7% had other atypical features. CLL with trisomy 12 was the only group with a high frequency of either CLL/PL (31%) or atypical morphology (24%). Atypical morphology and CLL/PL were even more frequent when trisomy 12 was associated with other chromosomal abnormalities (70% v 46%). The incidence of cases with CLL/PL and other atypical morphology was significantly lower in the other chromosome groups ( P <0.001. There were no differences in immunophenotype among the various groups except for a higher frequency of stronger Smlg and FMC7 expression in cases with trisomy 12, particularly those with CLL/PL and other atypical morphology. Our findings confirm that trisomy 12 defines a subgroup of CLL with more frequent atypical morphology, including CLL/PL, stronger SmIg and FMC7 expression, more advanced stages (B and C in 18%) and possibly worse prognosis. 相似文献
62.
目的:评价6mm巩膜小切口不缝合白内障超声乳化技术的疗效。方法:对91例老年性白内障患者行超声乳化并植 入光学部分为6mm的PMMA人工晶体,外切口位于角膜缘后1.0mm,内切口位于角膜缘内2.0mm的透明角膜处。结果:术前及术后1天,1周,1个月,3个月的角膜散光度分别为0.79±0.29D,1.19±0.58D,1.08±0.48D,1.06±0.56D,1.07±0.63D。术后1周内裸眼视力达到或高于0.5者占93.0%。结论:6mm巩膜小切口不缝合白内障超声乳化技术后角膜散光小,早期裸眼视力好且稳定。可植入PMMA人工晶体,降低手术费用。 相似文献
63.
Susanne M. A. Lens Paul Drillenburg Bianca F. A. den Drijver Gijs van Schijndel Steven T. Pals René A. W. van Lier & Marinus H. J. van Oers 《British journal of haematology》1999,106(2):491-503
In normal lymphoid tissues the tumour necrosis factor-receptor family member CD27 and its ligand CD70 have a restricted expression pattern. Previously, we reported that expression of CD27 is deregulated in B-cell leukaemias and lymphomas. Here we show that, although infrequently expressed by normal human B cells in vivo, CD70 is found on 50% of B-CLLs, 33% of follicle centre lymphomas, 71% of large B-cell lymphomas, and 25% of mantle cell lymphomas. Interestingly, in the majority of leukaemias and lymphomas examined, CD70 was found to have a capped appearance, a feature that coincided with co-expression of CD27. Functional analysis showed that a subset of B-CLLs could proliferate vigorously in response to CD70 mAb but not to CD27 mAb. This response was synergistically enhanced by ligation of CD40 but inhibited by the presence of IL-4. Additional experiments indicated that the proliferative response was due to an agonistic signal delivered via CD70, rather than blocking of negative signalling by CD27. Thus, next to its role as ligand, in a subset of malignant B cells CD70 can operate as receptor and as such might contribute to progression of these B-cell malignancies. 相似文献
64.
Katja C. Wolthers Sigrid A. Otto Susanne M. A. Lens Dinanda N. Kolbach Ren A. W. van Lier Frank Miedema Linde Meyaard 《European journal of immunology》1996,26(8):1700-1706
T cells express CD28 and CD27 which transduce co-stimulatory signals after interaction with their ligands on antigen-presenting cells (APC). These ligands, CD80, CD86 and CD70, are also expressed to some extent on activated T cells. Here, we show that in human immunodeficiency virus (HIV)-infected individuals, CD28 and CD27 expression is decreased on CD8+ T cells. On the other hand, T cell stimulation in vitro induced high CD80, CD86 and CD70 expression on T cells from HIV-infected individuals. It appeared that an inverted CD4:CD8 T cell ratio could explain this enhanced expression of co-stimulatory ligands. Indeed, high expression levels of CD80, CD86 and CD70 were found on activated CD8+ T cells from HIV− individuals cultured in the absence of CD4+ T cells. Addition of CD4+ T cells prevented this up-regulation. However, in HIV-infected individuals, addition of excess autologous or healthy control CD4+ T cells did not completely counteract up-regulation of co-stimulatory ligand expression on CD8+ T cells. Thus, to some extent, CD8+ T cells in HIV-infected individuals appeared to be refractory to CD4+ T cell-mediated regulation of ligand expression in vitro. Activated T cells from HIV-infected individuals and activated CD8+ T cells from healthy controls were able to act as accessory cells in CD3-induced T cell proliferation, which was dependent on cell-cell contact. Thus, we showed that T cells from HIV-infected individuals express enhanced levels of co-stimulatory ligands upon activation, which provides them with accessory cell properties. Enhanced stimulatory potential of these nonprofessional APC may contribute to persistently high levels of immune activation in HIV infection related to disease progression. 相似文献
65.
The binding of 125I-labelled recombinant human TNF alpha and IFN gamma to isolated human blood alpha 2-macroglobulin has been investigated using molecular sieving procedures and non-denaturing PA gel electrophoresis in combination with autoradiography. These studies revealed that both cytokines readily bind to the electrophoretically fast form of alpha 2M generated by methylamine or protease treatment of this protein. PAGE/SDS gel investigations indicated that TNF alpha bound non-covalently while the IFN gamma interaction was covalent in nature. Preliminary competition studies also indicate that cold TNF alpha and IL-2 are more effective than cold IFN gamma at inhibiting the binding of labelled IFN gamma to alpha 2M. Bioassays revealed that "native" alpha 2M or its derivatives at 2 mg/ml concentration did not impair the antiproliferative effects of TNF alpha and IFN gamma on susceptible bladder tumour cell lines. Furthermore they did not interfere in the induction of Class II antigen expression by IFN gamma on inducible cell lines or in a 2-site ELISA assay for TNF. 相似文献
66.
P Schneider H Takatsuka A Wilson F Mackay A Tardivel S Lens T G Cachero D Finke F Beermann J Tschopp 《The Journal of experimental medicine》2001,194(11):1691-1697
B cells undergo a complex series of maturation and selection steps in the bone marrow and spleen during differentiation into mature immune effector cells. The tumor necrosis factor (TNF) family member B cell activating factor of the TNF family (BAFF) (BLyS/TALL-1) plays an important role in B cell homeostasis. BAFF and its close homologue a proliferation-inducing ligand (APRIL) have both been shown to interact with at least two receptors, B cell maturation antigen (BCMA) and transmembrane activator and cyclophilin ligand interactor (TACI), however their relative contribution in transducing BAFF signals in vivo remains unclear. To functionally inactivate both BAFF and APRIL, mice transgenic for a soluble form of TACI were generated. They display a developmental block of B cell maturation in the periphery, leading to a severe depletion of marginal zone and follicular B2 B cells, but not of peritoneal B1 B cells. In contrast, mice transgenic for a soluble form of BCMA, which binds APRIL, have no detectable B cell phenotype. This demonstrates a crucial role for BAFF in B cell maturation and strongly suggests that it signals via a BCMA-independent pathway and in an APRIL-dispensable way. 相似文献
67.
68.
Jardi R Rodriguez F Buti M Costa X Valdes A Allende H Schaper M Galimany R Esteban R Guardia J 《Journal of hepatology》2004,40(3):507-514
BACKGROUND/AIMS: To determine the prevalence and significance of hepatitis B virus (HBV) basic core promoter (BCP) mutations and to establish their relationship with precore (preC) mutations, HBV genotypes and HBV-DNA levels. METHODS: BCP and preC mutations and genotypes were determined by sequencing. RESULTS: Genomic analysis was performed in 129 (71%) of 182 patients. BCP mutations were detected in 83% of 18 HBeAg-negative (e-) chronic hepatitis B (CHB) patients with fluctuating ALT levels, and in 76% of 58 e- CHB with elevated ALT. The prevalence was lower and similar, 55% in 30 HBeAg-positive CHB (e+ CHB) with elevated ALT and in 23 e- inactive carriers. Frequency of preC mutations was higher in e- CHB (80%) than in e- inactive carriers (65%). Among e- CHB, patients with elevated ALT and preC mutations at nt 1896 showed highest HBV-DNA, regardless of BCP mutations. BCP mutations were similar in genotypes A and D, while preC mutations were most common in genotype D (82 vs. 40%). Simultaneous presence of the main BCP (1762, 1764) and preC (1896, 1899) mutations was associated with the degree of histological injury. CONCLUSIONS: Combined BCP and preC mutational and genotype analysis provides clinically relevant information in the study of HBV infection. 相似文献
69.
Sabela Lens Jose L Calleja Ana Campillo Jose A Carrión Teresa Broquetas Christie Perello Juan de la Revilla Zoe Mari?o María-Carlota Londo?o Jose M Sánchez-Tapias álvaro Urbano-Ispizua Xavier Forns 《World journal of gastroenterology : WJG》2015,21(17):5421-5426
Telaprevir and Boceprevir are the first direct acting antivirals approved for chronic hepatitis C in combination with peg-interferon alfa and ribavirin.Pancytopenia due to myelotoxicity caused by these drugs may occur,but severe hematological abnormalities or aplastic anemia(AA) have not been described.We collected all cases of severe pancytopenia observed during triple therapy with telaprevir in four Spanish centers since approval of the drug in 2011.Among 142 cirrhotic patients receiving treatment,7 cases of severe pancytopenia(5%) were identified and three were consistent with the diagnosis of AA.Mean age was 59 years,five patients had compensated cirrhosis and two patients had severe hepatitis C recurrence after liver transplantation.Severe pancytopenia was diagnosed a median of 10 wk after the initiation of therapy.Three patients had pre-treatment hematological abnormalities related to splenomegaly.In six patients,antiviral treatment was interrupted at the onset of hematological abnormalities.Two patients died due to septic complications and one patient due to acute alveolar hemorrhage.The remaining patients recovered.Severe pancytopenia and especially AA,are not rare during triple therapy with telaprevir in patients with advanced liver disease.Close monitoring is imperative in this setting to promptly detect serious hematological disorders and to prevent further complications. 相似文献
70.
Zoe Mariño Anna Darnell Sabela Lens Victor Sapena Alba Díaz Ernest Belmonte Christie Perelló Jose Luis Calleja Maria Varela Manuel Rodriguez Carlos Rodriguez de Lope Susana Llerena Xavier Torras Adolfo Gallego Margarita Sala Rosa María Morillas Beatriz Minguez Jordi Llaneras María Reig 《Journal of hepatology》2021,74(2):491