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121.
122.
Abruzzo LV Rosales CM Medeiros LJ Vega F Luthra R Manning JT Keating MJ Jones D 《The American journal of surgical pathology》2002,26(5):630-636
We describe five patients with treated low-grade B-cell neoplasms who subsequently developed Epstein-Barr virus (EBV)-positive B-cell lymphoproliferative disorders (BLPDs). The low-grade B-cell neoplasms were B-cell chronic lymphocytic leukemia in four patients and splenic marginal zone lymphoma in one patient. All patients had received treatment with fludarabine for the low-grade B-cell neoplasm, and three had also received Campath-1H. The EBV-BLPDs arose 2-12 months after completion of fludarabine therapy and morphologically resembled the EBV-BLPDs that occur in the setting of iatrogenic immunodeficiency. Molecular genetic studies showed that these lesions were clonally distinct from the low-grade B-cell neoplasm in three of four cases assessed. Two patients did not receive therapy for the EBV-BLPD. The lesions regressed spontaneously in both patients but recurred in one. One patient underwent surgical excision and remains without evidence of the EBV-BLPD. One patient received aggressive multiagent chemotherapy with a complete response initially, but the EBV-BLPD recurred after 12 months. One patient received antiviral therapy and responded completely but died 2 months later of an opportunistic infection. We conclude that patients with low-grade B-cell neoplasms treated with fludarabine, possibly in combination with other immune suppressive agents, may subsequently develop EBV-BLPDs that morphologically resemble other iatrogenic immunodeficiency-associated BLPDs. Most are clonally distinct from the underlying low-grade B-cell neoplasm. A subset of these lesions may regress without systemic therapy. 相似文献
123.
Repeatability and reproducibility of macular thickness measurements with the Humphrey OCT system 总被引:5,自引:0,他引:5
PURPOSE: To assess the accuracy, precision, repeatability, and reproducibility of measurements made by the Humphrey optical coherence tomography (OCT) system (Humphrey-Zeiss Medical Systems, San Leandro, CA). METHODS: The performance of the system was first investigated by scanning a test object containing an air gap of known size. Measurements were repeated with water or glycerin in the gap. In the clinical setting, macular thickness measurements were obtained from a control group of 20 normal subjects. For analysis, these scans were divided into eight sections, each containing 10 A-scans. RESULTS: The average gap thickness was found to be close to the true value in all cases. The overall coefficients of intersession reproducibility were less than 1% for the test object and 1.51% for the control group. There was no significant difference between scans acquired during different sessions. The overall coefficients of repeatability for the test object were between 0.2% and 1.1% and between 1% and 2% for the control group. The range of normal retinal thickness in terms of the 5th and 95th percentiles was 222 to 248 microm in women and 234 to 257 microm in men. CONCLUSIONS: Measurements made from OCT scans were found to be accurate and precise. Introducing water or glycerin into the test object resulted in considerable degradation of the signal, but measurements of gap thickness were still shown to be accurate, precise, reproducible, and repeatable. Retinal thickness measurements in the macular area were repeatable and reproducible. This demonstrates that OCT is a useful tool in the monitoring of patients with conditions that affect macular thickness, even when there is considerable degradation of the OCT signal. 相似文献
124.
A multicentre retrospective audit of outcome of patients undergoing curative resection for rectal cancer 总被引:2,自引:0,他引:2
AIM: This study describes the outcome of patients with rectal cancer treated in four New Zealand public hospitals before the advent of specialised colorectal units in order to provide a baseline against which any changes in management can be measured. METHODS: A retrospective review of case notes of patients who underwent resection of rectal cancer with curative intent over a period of 7-10 years up to 1995 in Christchurch, Wellington, Nelson, and Masterton Public Hospital's, was undertaken. Patients were identified from hospital records using a combination of methods (pathology data bases, clinical case mix data, operating logs and audit data). Metastatic disease was considered to be present if confirmed on histology or the clinical course of the patient was consistent with metastatic disease. Patients were excluded if there was perioperative evidence of metastatic disease or if they had transanal excision. Previously published results from Auckland and Dunedin Hospitals are compared. RESULTS: 524 patients with rectal cancer were identified who had undergone surgery with curative intent in the four hospitals. The overall permanent stoma rate was 37%. The overall 30-day mortality was 2.9%, five-year survival was 63% and local recurrence at five years was 26%. CONCLUSION: While low perioperative mortality and good long-term survival were achieved, there were high rates of local recurrence. These data are a baseline against which the impact of new approaches to curative resection for rectal cancer can be measured. 相似文献
125.
Bisoprolol: a review of its use in chronic heart failure 总被引:3,自引:0,他引:3
Bisoprolol is a highly selective beta(1)-adrenoceptor antagonist. Administration of bisoprolol to patients with chronic heart failure is associated with increases in left ventricular function and reductions in heart rate; increases in heart rate variability are also seen. Two major randomised, double-blind, placebo-controlled, multicentre trials have examined the clinical efficacy of bisoprolol in combination with ACE inhibitors and diuretics in patients with stable chronic heart failure (New York Heart Association class III or IV): the Cardiac Insufficiency Bisoprolol Study (CIBIS; n = 641) and CIBIS II (n = 2 647). All-cause mortality (primary endpoint) was significantly lower in bisoprolol than in placebo recipients in CIBIS II (11.8 vs 17.3%) and was reduced by bisoprolol regardless of dosage. All-cause mortality was also lower in CIBIS (16.6 vs 20.9%) although the difference did not achieve statistical significance. In a meta-analysis of CIBIS and CIBIS II (n = 3 288), a relative reduction of 29% in the incidence of all-cause mortality was seen in bisoprolol versus placebo recipients; this analysis also demonstrated that bisoprolol reduces mortality in patients with chronic heart failure regardless of aetiology or severity. In CIBIS II, there were significantly fewer cardiovascular deaths, admissions to hospital for any reason, or cardiovascular deaths or cardiovascular hospitalisations (combined endpoint) in bisoprolol, compared with placebo, recipients (secondary endpoints). Compared with standard treatment alone, the addition of bisoprolol was a cost-effective option in chronic heart failure in UK, French, German and Swedish pharmacoeconomic studies. Bisoprolol is generally well tolerated in patients with chronic heart failure. In CIBIS II, adverse events occurring more commonly in bisoprolol than placebo recipients, regardless of causal relationship with the study medication, included dizziness, bradycardia, hypotension and fatigue. Bisoprolol recipients were less likely than placebo recipients to experience worsening of heart failure, dyspnoea or tachycardia. In both CIBIS and CIBIS II there was no significant difference between bisoprolol and placebo recipients in the incidence of permanent treatment withdrawal. In conclusion, adding the highly selective beta(1)-blocker bisoprolol to a treatment regimen comprising an ACE inhibitor and a diuretic significantly improves survival in patients with stable chronic heart failure and reduces the need for hospitalisation. The use of bisoprolol in this disorder is generally well tolerated and is cost effective. Thus, bisoprolol should be considered a standard treatment option when selecting a beta-blocker for use in combination with ACE inhibitors and diuretics in patients with stable, moderate to severe chronic heart failure. 相似文献
126.
An extended-release formulation of methylphenidate (Ritalin LA), a CNS stimulant that inhibits dopamine and noradrenaline (norepinephrine) reuptake into presynaptic neurons, has been developed for use in patients with attention deficit/hyperactivity disorder (ADHD). In children with ADHD and healthy male adults, extended-release methylphenidate 20mg was rapidly absorbed and demonstrated two distinct peak plasma concentrations approximately 4 hours apart. The absorption pharmacokinetics of extended-release methylphenidate 20mg, which closely mimics those of immediate-release methylphenidate 10mg given in two doses 4 hours apart, permits once-daily administration. In a 2-week randomised, double-blind, placebo-controlled trial in 134 evaluable children aged 6 to 12 years with ADHD, symptoms improved to a significantly greater extent with extended-release methylphenidate 10 to 40mg once daily than with placebo. Extended-release methylphenidate improved both inattention and hyperactivity symptoms and was effective in children with combined- (inattentive and hyperactive/impulsive) type or predominantly inattentive-type ADHD. In clinical trials, the safety and tolerability profiles of extended-release methylphenidate were consistent with that of the immediate-release formulation. 相似文献
127.
Giles FJ Bekele BN O'Brien S Cortes JE Verstovsek S Balerdi M Yared M Zhou X Kantarjian HM Keating MJ Thall P Albitar M 《British journal of haematology》2003,121(4):578-585
As the abnormal expression of p53 protein is prognostically significant in some human cancers, its significance in patients with B-cell chronic lymphocytic leukaemia (CLL) was assessed. Two investigators evaluated the percentage of bone marrow mononuclear cells that stained for p53, using biopsies stained with anti-p53 monoclonal antibody (DO-7), and graded the degree of staining (0, +, ++, +++). Samples from a cohort of 90 patients with CLL were studied (median age 60 years, range 30-89 years; 57 patients were (63%) previously untreated, 22 patients (24%) had received one or two prior regimens, 11 patients had received (12%) three to seven regimens. The overall percentage of cells positive for p53 staining was a median of 43 (range 1-88). No investigator effect was detected either in overall percentage cells rated p53 positive or on the degree of staining (Pearson's correlation coefficient 0.980, P-value < 0.001). A Cox proportional hazards model showed that the percentage of ++ and +++ p53-positive cells correlated with various prognostic factors in CLL (P < 0.0001). A multivariate model incorporating prior therapy, Rai stage, beta2 microglobulin (beta2M) and p53 expression showed that only the percentage of p53-positive cells and beta2M were predictive of survival, and enabled the development of a highly predictive model of survival based on these two parameters. 相似文献
128.
129.
The clinical and diagnostic relevance of CD23 expression in the chronic lymphoproliferative disease 总被引:1,自引:0,他引:1
DiRaimondo F Albitar M Huh Y O'Brien S Montillo M Tedeschi A Kantarjian H Lerner S Giustolisi R Keating M 《Cancer》2002,94(6):1721-1730
BACKGROUND: CD23 antigen is a cell surface protein considered important in the differentiation of chronic lymphocytic leukemia (CLL) from other lymphoid leukemias. METHODS: To better clarify CD23 role as a diagnostic tool, the authors retrospectively evaluated clinical and laboratory features of 372 patients who were referred to M.D. Anderson Cancer Center with a diagnosis of CLL or B-cell chronic lymphoproliferative disease. RESULTS: Most of the patients (91%) were CD19+/CD5+. Only 6% of these CD19+/CD5+ patients were CD23-. Overall, CD23- patients had the worse prognostic features compared with CD23+ cases, including anemia (P = 0.03), massive splenomegaly (P = 0.000), high lactate dehydrogenase (P = 0.007), high beta2-microglobulin (P = 0.006), older age (P = 0.001), and male gender (P = 0.02). Surface immunoglobulin expression was moderate/strong in 19 (82%) patients, and FMC-7 was positive in 22 (96%) patients. None of the 13 patients tested for CD10 expressed the antigen. Based on morphology, of the CD23, 16 (70%) were diagnosed with mantle cell leukemia (MCL) was diagnosed in 16 (70%) CD23- patients, 3 (13%) with splenic marginal-zone leukemia, 3 (13%) with prolymphocytic leukemia (PLL) or PLL/CLL, and 1 (4%) with CLL. No cyclin D1 protein expression was noted by Western blot analysis in the one case that showed typical CLL morphology, and this patient did not require therapy. On the whole, the survival rate of CD23- patients was significantly worse than that of patients with CD23+. In contrast, 15 of 32 (49%) CD19+/CD5- patients were CD23-. CD23 negativity in this group was not associated with distinct clinical features or outcome. Eleven (73%) of these patients were classified as having splenic marginal-zone lymphoma and 4 as having follicular lymphoma. CONCLUSIONS: These data indicate that CD23 negativity is rare in typical B-cell CLL, and CD23 negativity in patients with CD19+/CD5+ is suggestive of mantle cell leukemia a more aggressive disease with poor response to conventional therapy in which newer chemotherapy regimens such as hyper-CVAD may be more effective. 相似文献
130.
Lai R McDonnell TJ O'Connor SL Medeiros LJ Oudat R Keating M Morgan MB Curiel TJ Ford RJ 《Leukemia research》2002,26(9):849-855
Mantle cell lymphoma (MCL) is a distinct type of B-cell non-Hodgkin's lymphoma characterized by cyclin D1 overexpression and the cytogenetic abnormality, the t(11;14)(q13;q32). MCL cell lines have been difficult to establish and in vitro studies of these neoplasms are scarce. We describe the establishment and characteristics of a new MCL cell line, Mino. The cells are large, growing singly and in small clumps in vitro. By flow cytometry, the immunophenotype was compatible with MCL (i.e. CD5+CD20+CD23-FMC7+). Conventional cytogenetics showed hyperdiploidy with multiple complex karyotypic abnormalities, but no evidence of the t(11;14), proven to be present only by fluorescence in situ hybridization and polymerase chain reaction (PCR) methods. Western blots showed expression of cyclin D1 but no detectable cyclin D2 and cyclin D3; the retinoblastoma protein was predominantly phosphorylated. There was expression of tumor suppressor gene products including p53, p16(INK4a), and p21(WAF1). Sequencing of the TP53 gene revealed a mutation (codon 147(valine-->glycine)) in exon 5. Epstein Barr virus was absent. In summary, Mino is a new MCL cell line that may be useful to study the pathogenesis of MCL. 相似文献