Lithium augments GM-CSA generation in canine cyclic hematopoiesis

Cyclic hematopoiesis in gray collie dogs can be cured by lithium treatment. We examined the mechanism of lithium's effect by developing an assay for the canine equivalent of GM-CSF (called GM-CSA). Phytohemagglutinin (PHA)-stimulated canine blood mononuclear cells produce GM-CSA in a dose-dependent manner; this GM-CSA stimulates more neutrophil-containing colonies than does endotoxin-treated dog serum. Production of GM-CSA by PHA-stimulated normal dog cells was not altered by lithium. However, cells from gray collies during their neutrophilic period increased their GM-CSA when lithium (2 mEq/L) was added to low doses of PHA, whereas neutropenic gray collie cells did not. These data suggest that lithium could modulate cyclic hematopoiesis by increasing intramedullary GM-CSA at the time when marrow neutrophilic progenitor cells are at their nadir.     

Recipient humoral immunity against leukoreduced allogeneic platelets is suppressed by aminoguanidine, a selective inhibitor of inducible nitric oxide synthase

Leukoreduced allogeneic platelet transfusions have been previously shown to initially stimulate an in vitro cellular cytotoxicity and subsequently Induce the formation of immunoglobulin G (IgG) antidonor alloantibodies. To further characterize these responses and determine if they are related, recipient BALB/c H-2d mice were treated with aminoguanidine (AMG), a selective inhibitor of inducible nitric oxide synthase (iNOS), and transfused weekly with 2 x 10(8) C57BL/6 H2b platelets. In control, non-AMG-treated mice, transfusion significantly (P < .01) increased serum levels of interferon-gamma (IFN-gamma) by day 1 posttransfusion (PT). IFN-gamma returned to pretransfusion levels by day 3 PT, and its production was not affected by AMG treatment. Serum interleukin-4 (IL-4), on the other hand, was undetectable before and during the transfusion protocol. By day 3 PT, recipient spleen cells could mediate in vitro anti-P815 (auto), anti-EL4 (allo), and anti-R1.1 (third-party MHC) cytotoxicity, and these responses were maximal by day 7 PT. Concurrently, a significant reduction in the vitro ability of recipient splenocytes to respond to Concanavalin A (ConA) was observed; this was not seen with lipopolysaccharide (LPS) stimulation. Elevated levels of NO2- were found in the ConA culture supernatants from transfused mice at day 3 PT. Serum antidonor alloantibodies were detected by the fifth platelet transfusion. AMG treatment of recipient mice significantly inhibited the transfusion. Induced cytotoxicity and ConA-stimulated NO2- production, and restored ConA-induced proliferation to normal levels. AMG appeared to selectively inhibit platelet-induced alloantibody production in that it did not affect antibody production induced by transfusions with 10(5) allogeneic leukocytes or by immunization with a foreign protein antigen, human gamma globulin, in adjuvant therapy. These results indicate that an in vivo AMG-sensitive mechanism is essential for recipients to initiate a humoral IgG immune response against allogeneic platelets.     

Hypermethylation of the 5' region of the calcitonin gene is a property of human lymphoid and acute myeloid malignancies

An abnormal increase in numbers of CCGG sites methylated in the 5' region of the human calcitonin (CT) gene occurred in tumor cell DNA samples from 90% (17 of 19) of patients with non-Hodgkin's T and B cell lymphoid neoplasms and in 95% (21 of 22) of tumor cell DNA samples from patients with acute nonlymphocytic leukemia (ANLL). The changes were not seen in patients with chronic myelogenous leukemia (0 of 9). The abnormal methylation patterns appear to be a property only of transformed or malignant cells since they were not found in DNA from nonneoplastic adult tissues including sperm, early myeloid progenitor cells, benign lymphoid hyperplasia, peripheral lymphocytes stimulated to divide, or early myeloid progenitor cells (obtained by immunoaffinity using anti-My-10 antibody), but they did appear after Epstein-Barr virus transformation of lymphocytes. Moreover, during the course of therapy in patients with ANLL, the hypermethylation pattern reflects the presence of the leukemic clone even in normal-appearing granulocytes derived from this clone. The increased methylation of the CT gene may then provide an important molecular marker for biologic events in human cell transformation or tumor progression and may prove clinically useful in monitoring patients with lymphoid and acute myelogenous neoplasms.     

Heterogeneity of the T-cell receptor delta gene indicating subclone formation in acute precursor B-cell leukemias

Precursor B-cell acute lymphoblastic leukemias (B-ALLs) have been shown to be oligoclonal at the Ig heavy-chain (IgH) gene level in up to 40% of cases by Southern blot hybridization. In contrast, oligoclonality as deduced from diversity of T-cell receptor (TcR)-delta gene rearrangements of the immature types (ie, V delta 2-D delta 3, D delta 2-D delta 3) has not been reported, so far. We detected oligoclonality characterized by the coexistence of different junctional regions of identical V delta 2-D delta 3 rearrangements in four childhood precursor B-ALLs. No variation was found in the IgH gene status. Therefore, we define these populations as subclones. Two leukemias displayed the variants in an unequal proportion. In the other two leukemias, for which similar quantities of the coexisting rearrangements were detected, single cell-nuclei polymerase chain reaction (PCR) showed two separate leukemic populations. Subclone formation could not be demonstrated by Southern blot hybridization, but was detectable after PCR amplification of the V delta 2-D delta 3 rearrangement and separation by polyacrylamide gel electrophoresis. The variants arose independently from each other, as deduced from their individual sequences. Using subclone-specific oligonucleotides for hybridization to amplified DNA obtained at diagnosis and during follow- up from bone marrow samples, we demonstrate, (1) specificity of all subclone-deduced probes, (2) that one residual leukemic cell can be detected in 10(4) to 10(5) normal mononuclear cells in a semiquantitative assay, and (3) that none of the subclones persisted after induction therapy. We propose that in a leukemic cell population, TcR-delta gene diversity arises after rearrangements of the IgH genes resulting in apparent clonality at the IgH gene level. However, cells are oligoclonal, if the TcR-delta gene rearrangements are considered. As various subclones may respond differently to chemotherapy, they may hamper the detection of minimal residual disease. Therefore, we use all subclone-specific oligonucleotides for hybridization to amplified DNA from follow-up samples.     

Pathologic effects of plasma from patients with thrombotic thrombocytopenic purpura on platelets and cultured vascular endothelial cells

The pathologic hallmarks of thrombotic thrombocytopenic purpura (TTP) include endothelial cell proliferation and subendothelial hyalin deposits in the microvasculature leading to symptomatic thrombotic occlusions. Plasma or sera from three consecutive patients with TTP were subjected to multiple analyses to determine whether they induce endothelial injury and/or platelet activation, two pathogenic mechanisms that may account for this disorder. Sera were utilized in a microcytotoxicity assay against cultured human umbilical vein endothelial cells (EC). These cells were assessed ultrastructurally and with immunofluorescence techniques to ascertain the nature of inflicted cell damage. Control plasmas were obtained from healthy volunteers as well as patients with immune complex disease and the adult hemolytic uremic syndrome. In the presence of TTP serum, cell kill of 3H-proline- labeled EC averaged 42% versus 8.6% for control sera. Cytotoxicity induced by an IgG fraction of TTP sera averaged 70% versus 16.8% for control IgG. Removal of IgG by immune precipitation diminished cytotoxicity by 70%. Using indirect immunofluorescence, IgG was detected on EC incubated with TTP serum but not on EC treated with control serum. Ultrastructural changes became apparent within 30 min after exposure of cultured EC to TTP serum. Virtually every cell developed numerous cytoplasmic inclusions rarely seen in EC in the presence of normal serum. Prolonged incubation with the TTP serum led to progressive cytolysis, terminating with complete cytoplasmic and nuclear degeneration. Plasma from all three patients with TTP caused spontaneous aggregation of normal washed platelets as monitored by aggregometry. No spontaneous aggregation occurred in response to control plasmas. These results indicate that the sera of the three TTP patients studied were able to mediate time-dependent immune destruction of human cultured endothelial cells and that their plasmas were capable of causing spontaneous aggregation of normal human platelets in vitro. It would seem likely that these mechanisms are also operative in vivo to produce the endothelial destruction as well as the thrombotic vascular occlusions seen in this disorder.     

Platelet modulation of polymorphonuclear leukocyte shear induced aggregation

A cone and plate viscometer and Coulter Counter were used to study platelet modulation of polymorphonuclear leukocyte (PMNL) aggregation caused by controlled shear stress. As an index of aggregation, the large-particle percentage (LPP) was calculated. This represents the ratio of aggregated cell count to total cell count. PMNL suspensions in buffer (1.0 X 10(7) cells per milliliter, final concentration) did not show any aggregate formation at shear stresses below 150 dynes/cm2 for one minute exposure time (LPP less than 3%). However, there was PMNL aggregation in mixed PMNL and platelet-rich plasma suspensions in this shear stress range. Supernatant plasma from sheared platelets initiated PMNL aggregation at moderate shear stress (150 dynes/cm2 for one minute; LPP, 20.3% +/- 2.5%). In contrast, platelet release factors, such as adenosine diphosphate (2 mumol/L) and serotonin (2 mumol/L) did not cause PMNL aggregation (LPP, 2.9% +/- 1.2% and 3.3% +/- 0.8%, respectively). The use of a cyclo-oxygenase inhibitor (acetylsalicylic acid, 50 mumol/L) did not suppress the aggregation of PMNLs after shear (LPP, 20.1% +/- 2.4%). However, preincubation with nordihydroguaiaretic acid (10 mumol/L), an inhibitor of C-5 and C-12 lipoxygenase, and 6,9- deepoxy-6,9-(phenylimino)-6,8-prostaglandin I1 (U-60257, 10 mumol/L), an inhibitor of C-5 lipoxygenase in human leukocytes, suppressed this aggregation (LPP, 9.1% +/- 2.5% and 10.4% +/- 3.2%, respectively). Also, the formation of lipoxygenase products (5-HETE, 12-HETE, 15-HETE, and LTB4) activated by shear stress was documented by reversed phase- high-performance liquid chromatography (RP-HPLC). These data support the possibility of a cooperation between platelets and leukocytes in shear-induced PMNL aggregation that is dependent on C-12 or C-5 lipoxygenase activity, or both.     

应用OHIP-14评价2种种植系统OHRQoL的差异

目的 研究2种种植系统修复治疗后口腔健康相关生活质量（OHRQoL）的差异,为临床种植系统的选择和治疗效果的评估提供参考。方法 临床收集门诊且符合纳入标准的种植义齿修复患者100例,其中50例A组行安多健（Anthogry）种植系统修复,50例B组行士卓曼（Straumann）种植系统修复。采用口腔健康影响程度量表（OHIP-14）中文版作为测量方法研究2种种植系统修复6个月后患者OHRQoL的得分情况,比较两种种植系统修复后患者的OHRQoL的差异。结果 A组："生理性疼痛"得分最高（P₅₀=3.00）,其次为"心理不适,心理障碍"（P₅₀=2.00）;"吃什么东西都不舒服"最常给牙列缺损患者带来负面影响。B组："生理性疼痛"、"心理不适"、"生理障碍"三者得分最高（P₅₀=2.00）,其次为"心理障碍"（P₅₀=1.5）;"对自己的饮食很不满意"最常给牙列缺损患者带来负面影响。治疗后Anthogry与Straumann量表总得分差异无统计学意义（P>0.05）。结论 2种种植系统均能改善患者口腔健康状况,患者对两种系统的整体主观感受并无明显差异。     

补肺健脾益肾方治疗对老年COPD稳定期患者T淋巴细胞亚群、BODE指数及生活质量的影响

目的:评价补肺健脾益肾方治疗老年慢性阻塞性肺疾病(COPD)稳定期的疗效及对患者外周血T淋巴细胞亚群、BODE指数及生活质量的影响.方法:将80例中医辨证为肺脾肾气虚型COPD稳定期患者随机分组,对照组(40例)仅采取常规西医治疗,而观察组(40例)在常规西医治疗的基础上联合补肺健脾益肾汤,治疗8周后比较临床疗效及患者外周血T淋巴细胞亚群、BODE指数及生活质量的变化.结果:经治疗后观察组BODE指数及BMI积分、FEV1积分、MMRC积分、6MWT积分均较对照组明显减少,差异具有统计学意义(P＜0.05);经治疗后观察组CD3+、CD4+及CD4+/CD8+较对照组明显升高,CD8 +水平较对照组明显降低,差异具有统计学意义(P＜0.05);两组经治疗后肺功能指标FEV1和FEV1/FVC均较治疗前有明显改善,差异具有统计学意义(P＜0.05);两组治疗后SGRQ评分均较治疗前明显降低,但观察组治疗后SGRQ评分明显低于对照组,差异具有统计学意义(P＜0.05).结论:补肺健脾益肾方用于老年COPD稳定期治疗可改善患者肺功能及BODE指数,提高生活质量,增强细胞免疫功能.     

Toxic effect of puromycin on erythrocyte membranes which is unrelated to inhibition of protein synthesis

Exposure of rabbit or human erythrocytes to concentrations of puromycin as low as 7 x 10(-4)M for 2 hr causes damage to the cell membrane, as evidenced by increased susceptibility of the cells to hyposmotic lysis, increased cell rigidity, and ultrastructural changes consistent with severe membrane damage. Puromycin causes a concentration-dependent internalization of the erythrocyte membrane, resulting in vacuolization of the cells, at concentrations between 7 x 10(-4) M and 10(-2) M. Since the erythrocyte does not synthesize protein, the data indicate that puromycin has a direct toxic effect on erythroid cell membranes which is unrelated to its action in inhibiting the synthesis of protein.