Total radical trapping antioxidant potential (TRAP) and exercise

The relationship between physical activity, physical fitness and total radical trapping antioxidant potential (TRAP) was examined in the Northern Ireland Health and Activity Survey. This was a cross-sectional population study (n = 1600) using a two-stage probability sample of the population. TRAP was calculated using the sum of the individual serum antioxidant concentrations (urate, protein thiols, ascorbate, alpha tocopherol and bilirubin) multiplied by their respective stoichiometric values. Physical fitness was determined by estimation of VO2max by extrapolation from submaximal oxygen uptake, and physical activity was recorded by computer-assisted interview. Mean serum TRAP concentrations were significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female smokers had significantly lower TRAP values than non-smokers (males p < 0.0001, females p = 0.02). In females, there was a positive relationship of TRAP with age (p < 0.001) and body mass index (p < 0.001) but a negative relationship with physical fitness (p < 0.05). The known beneficial effects of exercise and activity do not appear to be directly mediated through increased antioxidant status.      

Platelet membrane glycoprotein changes during the preparation and storage of platelet concentrates

Previous studies of platelet membrane glycoproteins during blood bank storage have reported conflicting results. This study assessed two major plasma membrane glycoproteins (GP Ib and GP IIb), an alpha-granule membrane protein (GMP-140), and the concentration of platelet membrane microparticles in cell-free plasma during routine hospital blood bank platelet storage. 125I-monoclonal antibody binding was used to measure membrane glycoproteins on the surface of intact platelets and to measure the concentration of membrane microparticles in cell-free plasma. Platelet concentrates were stored at room temperature in polyolefin bags for 7 days. In this blood bank, two types of rotators are routinely used for platelet concentrate storage: a 2-rpm circular tumbler rotator and a 6-rpm elliptical rotator. Different results were obtained with the rotators. With the tumbler rotator, there was no loss of platelets and antibody binding to GP Ib remained normal. With the elliptical rotator, one third of platelets were lost into clumps during storage, and a 50 percent decrease of antibody binding to GP Ib occurred in the remaining single platelets. There was no loss of antibody binding to GP IIb with either rotator. Antibody binding to GMP-140 increased equally in both rotators indicating that the remaining single platelets had secreted about 16 percent of their alpha-granule contents. The plasma concentration of platelet membrane microparticles was greater in the bags stored in the elliptical rotator. These results indicate that it is possible to maintain the normal concentration of platelet membrane glycoproteins Ib and IIb during 7 days of room-temperature blood bank storage.(ABSTRACT TRUNCATED AT 250 WORDS)     

In Vivo Feedback Predicts Parent Behavior Change in the Attachment and Biobehavioral Catch-up Intervention

Understanding mechanisms and active ingredients of intervention is critical to training clinicians, particularly when interventions are transported from laboratories to communities. One promising active ingredient of parenting programs is clinicians’ in vivo feedback regarding parent–child interactions. The present study examined whether a form of in vivo feedback, in the moment commenting, predicted treatment retention and parent behavior change when the Attachment and Biobehavioral Catch-up (ABC) intervention was implemented in a community setting. Observational data were collected from 78 parent–child dyads (96% mothers; M age = 29 years; 81% minority; infants’ M age = 12 months; 90% minority) across 640 sessions conducted by 9 clinicians (100% female, M age = 39; 67% minority) in Hawaii. Parental behavior was assessed with a semistructured play task before and after intervention. Clinicians’ in-the-moment feedback to parents was assessed from intervention session videos. Clinicians’ frequency and quality of in-the-moment feedback predicted change in parental intrusiveness and sensitivity at posttreatment. Frequency of in-the-moment feedback also predicted likelihood of retention. Hierarchical linear modeling demonstrated strong support for these associations at the between-clinician level, and limited additional support at the within-clinician (i.e., between-case) level. Thus, a hypothesized active ingredient of treatment, in-the-moment feedback, predicted community-based ABC outcomes. The results complement lab-based evidence to suggest that in vivo feedback may be a mechanism of change in parenting interventions. Helping clinicians to provide frequent, high-quality in vivo feedback may improve parenting program outcomes in community settings.     

91例胃粘膜EB病毒感染的检测

ＥＢ病毒是一种肿瘤病毒，与人类鼻咽癌、淋巴瘤关系密切。近年来ＥＢ病毒相关性胃癌在国外已有报道。本文通过胃镜活检，对９１例胃粘膜行ＰＣＲ方法检测ＥＢ病毒感染。一、材料与方法：９１例患者均为我院１９９６年３月～６月门诊及住院胃镜检查者。男５８例，女３３例...     

A technique for the flow cytometric analysis of lymphocytes bearing histamine receptors

Histamine receptors have been demonstrated on lymphocyte membranes by a variety of techniques. We now report a method that allows for the flow cytometric analysis of histamine receptors on human peripheral T cells. Histamine is conjugated to fluoresceinated human albumin by the coupling agent ECDI. This conjugated histamine compound (FHA-his) binds to approximately 45% of T cells. Fluoresceinated human albumin alone (FHA), not conjugated to histamine, does not bind to T cells. In addition, unconjugated histamine can inhibit completely the binding seen with FHA-his. We conclude that this technique demonstrates specific FHA-his binding to histamine receptors on T cells and can be used to determine the number of cells bearing such receptors. In addition, the reagent could be used with a cell sorter to isolate distinct histamine-receptor-bearing (HR+) cells for further immunologic study.     

Adoptive immunotherapy evaluating escalating doses of donor leukocytes for relapse of chronic myeloid leukemia after bone marrow transplantation: separation of graft-versus-leukemia responses from graft-versus-host disease

Infusions of large numbers (> 10(8)/kg) of donor leukocytes can induce remissions in patients with chronic myeloid leukemia (CML) who relapse after marrow transplantation. We wanted to determine if substantially lower numbers of donor leukocytes could induce remissions and, if so, whether this would reduce the 90% incidence of graft-versus-host disease (GVHD) associated with this therapy. Twenty-two patients with relapsed CML were studied: 2 in molecular relapse, 6 in cytogenetic relapse, 10 in chronic phase, and 4 in accelerated phase. Each patient received escalating doses of donor leukocytes at 4- to 33-week intervals. Leukocyte doses were calculated as T cells per kilogram of recipient weight. There were 8 dose levels between 1 x 10(5) and 5 x 10(8). Lineage-specific chimerism and residual leukemia detection were assessed using sensitive polymerase chain reaction (PCR) methodologies. Nineteen of the 22 patients achieved remission. Remissions were achieved at the following T-cell doses: 1 x 10(7) (n = 8), 5 x 10(7) (n = 4), 1 x 10(8) (n = 3), and 5 x 10(8) (n = 4). To date, 15 of the 17 evaluable patients have become BCR-ABL negative by PCR. The incidence of GVHD was correlated with the dose of T cells administered. Only 1 of the 8 patients who achieved remission at a T-cell dose of 1 x 10(7)/kg developed GVHD, whereas this complication developed in 8 of the 11 responders who received a T-cell dose of > or = 5 x 10(7)/kg. Three patients died in remission, 1 secondary to marrow aplasia, 1 of respiratory failure and 1 of complications of chronic GVHD. Sixteen patients who were mixed T-cell chimeras before treatment became full donor T-cell chimeras at the time of remission. Donor leukocytes with a T-cell content as low as 1 x 10(7)/kg can result in complete donor chimerism together with a potent graft-versus-leukemia (GVL) effect. The dose of donor leukocytes or T cells used may be important in determining both the GVL response and the incidence of GVHD. In many patients, this potent GVL effect can occur in the absence of clinical GVHD.     

Differential effect of Serratia protease on platelet surface glycoproteins Ib and V

The effect of a zinc metalloprotease from Serratia marcescens on platelet surface glycoproteins (GP) Ib and V was analyzed. Increasing protease treatments caused progressive loss of GP Ib with appearance of the major fragment, glycocalicin, in the supernatant solution. No GP V was detected in the supernatant solution, and protease-pretreated platelets had the same capacity as control platelets to release fragment 1 of GP V in response to thrombin. The Serratia protease- pretreated platelets did show the lag before thrombin-induced dense granule secretion, characteristic of platelets modified by pretreatment with other nonstimulating proteases. Treatment with Serratia protease gives the only demonstrated selective loss of GP Ib without apparent effect on GP V. It suggests that GP V (1) does not depend on GP Ib for its association with platelets and (2) is not the substrate for protease modification of platelet function.     

Erythroid failure in Diamond-Blackfan anemia is characterized by apoptosis

Programmed cell death, also known as apoptosis, is frequently initiated when cells are deprived of specific trophic factors. To investigate if accelerated apoptosis contributes to the pathogenesis of Diamond- Blackfan anemia (DBA), a rare pure red blood cell aplasia of childhood, we studied the effect of erythropoietin (epo) deprivation on erythroid progenitors and precursors from the bone marrow of DBA patients as compared with hematologically normal controls. Apoptosis in response to epo deprivation was evaluated by enumeration of colony-forming unit- erythroid (CFU-E)- and burst-forming unit-erythroid (BFU-E)-derived colonies in plasma clot semisolid culture and by the identification of typical DNA oligosomes by gel electrophoresis from marrow mononuclear cells in liquid culture. In all DBA patients there was a marked decrease in CFU-E- and BFU-E-derived colony formation compared with normal controls at comparable time points of epo deprivation, with a complete loss of CFU-E-derived colonies in semisolid culture by 9 hours of epo deprivation versus 48 hours in controls. The BFU-E-derived colony response to epo deprivation displayed a similar pattern of decrement. Apoptotic changes assessed by the presence of characteristic DNA fragmentation began in the absence of epo deprivation and were readily detected within 3 hours of epo deprivation in DBA cultures versus 9 hours in controls. We conclude that DBA is characterized by accelerated apoptosis as measured by the loss of erythroid progenitor clonogenicity and increased progenitor and precursor DNA fragmentation leading to the formation of characteristic oligosomes, consistent with an intrinsic erythroid-progenitor defect in which increased sensitivity to epo deprivation results in erythroid failure.