Phenotypic markers and BCL-1 gene rearrangements in B-cell chronic lymphocytic leukemia: a Cancer and Leukemia Group B study

The markers, CD11b, CD11c, CD14, CD21, CD23, CD25, CD38, and FMC7 were correlated with morphologic and other laboratory and clinical characteristics of 127 patients with untreated CD5+ chronic lymphocytic leukemia (CLL). Only CD38 and CD21 were significantly associated with atypical CLL morphology. The integrin associated markers CD11b and CD11c were associated with lower leukocyte count (white blood cell count [WBC]) and lower Rai stage. By contrast, the activation antigen CD23 was associated with a higher WBC, higher Rai stage, younger age group, and the presence of lymphadenopathy. Therefore, we conclude that CD23 positivity may reflect a more aggressive form of CLL, and CD11b and CD11c positivity a less aggressive form. The BCL-1 gene rearrangement was present in 5 of 84 (6%) CLL cases examined and was associated with atypical morphology and surface expression of CD11b. Patients with a BCL-1 gene rearrangement may represent a CLL subset or possibly a different B-cell disease.     

The Impact of Modern Noninvasive Cardiac Imaging on Coronary Intervention Rates

Objectives

It remains still unclear whether the use of modern noninvasive diagnostic modalities for evaluation of coronary artery disease (computed tomography coronary angiography (CTCA), nuclear myocardial perfusion imaging (MPI)) were able to change the “diagnostic yield” of invasive coronary angiography (ICA).

Methods

The total number of ICA in the years 2000–2009 was related to the number of percutaneous interventions (PCIs) and we assessed whether there was a significant trend over time using time series analyses. We compared these data with the number of patients undergoing CTCA and nuclear MPI in the same time period.

Results

During the 10‐year observational period, 23,397 ICA were performed. The proportion of purely diagnostic ICA (without PCI) remained stable over the whole study period (tau = ?0.111, P = 0.721). A CTCA program was initiated in 2005 and 1,407 examinations were performed until 2009. Similarly, the number of nuclear MPI increased from 2,284 in the years 2000–2004 to 5,260 in the years 2005–2009 (P = 0.009).

Conclusion

Despite increasing availability, noninvasive testing modalities did not significantly alter the rate of purely diagnostic ICA, and still are underused as gatekeeper to ICA. Further effort is needed to optimize the use of noninvasive imaging modalities in the work‐up process for coronary artery disease. (J Interven Cardiol 2014;27:50–57)

     

Pharmacokinetics of [18F]flutemetamol in wild-type rodents and its binding to beta amyloid deposits in a mouse model of Alzheimer’s disease

Purpose

The aim of this study was to investigate the potential of [¹⁸F]flutemetamol as a preclinical PET tracer for imaging β-amyloid (Aβ) deposition by comparing its pharmacokinetics to those of [¹¹C]Pittsburgh compound B ([¹¹C]PIB) in wild-type Sprague Dawley rats and C57Bl/6N mice. In addition, binding of [¹⁸F]flutemetamol to Aβ deposits was studied in the Tg2576 transgenic mouse model of Alzheimer’s disease.

Methods

[¹⁸F]Flutemetamol biodistribution was evaluated using ex vivo PET methods and in vivo PET imaging in wild-type rats and mice. Metabolism and binding of [¹¹C]PIB and [¹⁸F]flutemetamol to plasma proteins were analysed using thin-layer chromatography and ultrafiltration methods, respectively. Radiation dose estimates were calculated from rat ex vivo biodistribution data. The binding of [¹⁸F]flutemetamol to Aβ deposits was also studied using ex vivo and in vitro autoradiography. The location of Aβ deposits in the brain was determined with thioflavine S staining and immunohistochemistry.

Results

The pharmacokinetics of [¹⁸F]flutemetamol resembled that of [¹¹C]PIB in rats and mice. In vivo studies showed that both tracers readily entered the brain, and were excreted via the hepatobiliary pathway in both rats and mice. The metabolism of [¹⁸F]flutemetamol into radioactive metabolites was faster than that of [¹¹C]PIB. [¹⁸F]Flutemetamol cleared more slowly from the brain than [¹¹C]PIB, particularly from white matter, in line with its higher lipophilicity. Effective dose estimates for [¹¹C]PIB and [¹⁸F]flutemetamol were 2.28 and 6.65?μSv/MBq, respectively. Autoradiographs showed [¹⁸F]flutemetamol binding to fibrillar Aβ deposits in the brain of Tg2576 mice.

Conclusion

Based on its pharmacokinetic profile, [¹⁸F]flutemetamol showed potential as a PET tracer for preclinical imaging. It showed good brain uptake and was bound to Aβ deposits in the brain of Tg2576 mice. However, its high lipophilicity might complicate the analysis of PET data, particularly in small-animal imaging.     

Functional and biophysical analyses of the class XIV Toxoplasma gondii Myosin D

Summary The obligate intracellular parasite Toxoplasma gondii uses gliding motility to migrate across the biological barriers of the host and to invade cells. This unique form of locomotion requires an intact actin cytoskeleton and involves at least one motor protein (TgMyoA) that belongs to the class XIV of the myosin superfamily. TgMyoA is anchored in the inner membrane complex and is essential for the gliding motion, host cell invasion and egress of T. gondii tachyzoites. TgMyoD is the smallest T. gondii myosin and is structurally very closely related to TgMyoA. We show here that TgMyoD exhibits similar transient kinetic properties as the fast single-headed TgMyoA. To determine if TgMyoD also contributes to parasite gliding motility, the TgMyoD gene was disrupted by double homologous recombination. In contrast to TgMyoA, TgMyoD gene is dispensable for tachyzoite propagation and motility. Parasites lacking TgMyoD glide normally and their virulence is not compromised in mice. The fact that TgMyoD is predominantly expressed in bradyzoites explains the absence of a phenotype observed with myodko in tachyzoites and does not exclude a role of this motor in gliding that would be restricted to the cyst forming but nevertheless motile stage of the parasite.Both authors contributed equally to the work.     

Bone marrow transplantation for refractory acute leukemia in 34 patients with identical twins

Thirty-four patients aged 4-67 yr (median 17) with acute lymphocytic leukemia (ALL) (18 patients) or acute nonlymphocytic leukemia (ANL) (16 patients) who failed to enter complete remission (CR) or relapsed on conventional chemotherapy were treated with cyclophosphamide (CY), 60 mg/kg/day for 2 days, 1000 rad total body irradiation, and a marrow transplant from a genotypically identical normal twin. Sixteen of the patients received additional chemotherapy within the week before CY. After the transplant, 23 patients received immunotherapy consisting of killed autologous leukemic cells and/or normal twin peripheral blood lymphocytes, 16 as part of a prospectively randomized study. One moribund patient died before engraftment. Nine patients (6 ALL, 3 ANL) continued to have detectable leukemic cells. Twenty-four patients (70%) achieved CR. One of them died of viral hepatitis at 1 mo and another of viral interstitial pneumonitis at 4 mo in CR. Fourteen patients (7 ALL, 7 ANL) relapsed 2-16 mo (median 4) after transplantation. However, 8 patients (24%) (3 ALL, 5 ANL) remain in CR without any maintenance chemotherapy at 29-103 mo (median 80) after the transplant. The end results were not signficantly influenced by the type of leukemia, the immediated pre-CY chemotherapy, or the immunotherapy. The results show that this approach, even when applied to endstage patients with acute leukemia in relapse, causes tolerable morbidity, rare nonleukemic deaths, and frequent remissions, some of which represent cures.     

A prospective randomized comparison of total body irradiation-etoposide versus busulfan-cyclophosphamide as preparatory regimens for bone marrow transplantation in patients with leukemia who were not in first remission: a Southwest Oncology Group study

Two novel preparatory regimens for conditioning of patients with leukemia for allogeneic bone marrow transplantation (BMT) from histocompatible sibling donors have been tested in a phase III trial under the auspices of the Southwest Oncology Group (SWOG 8612). These two regimens consisted either of fractionated total body irradiation and etoposide (FTBI/VP-16) or high-dose busulfan with cyclophosphamide (BU/CY). Only patients who had failed prior conventional management at least once were study eligible, ie, no patients with acute leukemia in first remission (CR) or in first chronic phase (CP) of chronic myelogenous leukemia (CML) participated. Patients were stratified according to the following risk criteria: "good-risk" patients were those who were in second CR of their acute leukemia or in accelerated phase (AP) of CML; "poor-risk" patients had further advanced stages of leukemia. During a 52-month period, 131 patients were registered of whom 122 (93%) were study eligible. Sixty-one eligible patients were randomized to the FTBI/VP-16 arm and 61 to the BU/CY regimen. Of these 122 patients, 114 (93%) proceeded to BMT according to protocol. Posttransplant immunosuppression to prevent graft-versus-host disease (GVHD) consisted of cyclosporine and prednisone (CSA/PSE). Neither overall survival nor disease-free survival (DFS) differed significantly between the two treatment groups (P = .89 and .69, respectively). Estimated DFS for "good-risk" patients who had been prepared with the FTBI/VP-16 regimen was 55% +/- 11%, as compared with patients treated with BU/CY whose DFS figure was 34% +/- 10% (P = .30). For "poor-risk" candidates, the DFS rates at 24 months were 17% +/- 6% (for FTBI/VP-16) and 24% +/- 8% (for BU/CY), respectively (P = .81). These figures do not differ significantly, especially in view of the fact that the "good- risk" patients prepared with the FTBI/VP-16 regimen were younger than those treated with BU/CY. Both regimens were well tolerated with no regimen-related deaths encountered during the 6-week period after BMT. This study also confirmed the efficacy of the CSA/PSE combination in the prevention of GVHD with 23 of 113 (20%) of BMT recipients developing moderate to severe acute GVHD. The leading cause for treatment failure was leukemic relapse (45 of the 114 BMT recipients suffered a recurrence of their leukemia), whereas 38 patients died without evidence of relapse. Thirty-one patients are alive and in continued CR after marrow transplantation; four are alive in relapse.(ABSTRACT TRUNCATED AT 400 WORDS)     

The influence of sera, follicular fluids and seminal plasma on human sperm-zona pellucida binding

The purpose of this study was to assess the influence of male, female and fetal cord sera, follicular fluid, and seminal plasma on human sperm-zona pellucida binding, using the hemizona assay. Steroids, gonadotrophins, growth hormone and prolactin concentrations in follicular fluid and sera were also analysed. The influence of follicular fluid (10 or 50%, v/v) and sera (10%) on sperm-zona pellucida binding was investigated by supplementing the sperm processing medium as well as the sperm-hemizona incubation medium. Different seminal plasma concentrations (1 or 10%) were added to the sperm-hemizona incubation medium. Supplementation with 10% day 3 donor serum was used as a control throughout experimentation. Although supplementation with male sera and fetal cord serum exerted a stimulatory effect (36 and 90% respectively; P < 0.029) on sperm-zona pellucida binding, hemizona indices obtained with addition of male sera, fetal cord serum and sera obtained from sub-fertile in-vitro fertilization (IVF) patients on day 12 of their menstrual cycle did not differ significantly (P > 0.05). Final progesterone concentrations in sperm-zona pellucida incubation media (10% follicular fluid supplementation), which ranged from 0.788 to 3.85 microg/ml, enhanced sperm binding to the zonae by >100% (P < 0.02). The utilization of follicular fluid (10%) as a natural physiological stimulus to enhance sperm-zona pellucida binding in an IVF setting is recommended. The presence of seminal plasma in the spermzona pellucida incubation media showed no beneficial effect on the binding ability of sperm, and can be viewed as an unfavourable substance in the proximity of the oocyte.