Hydrostatic mechanisms may contribute to the pathogenesis of human re-expansion pulmonary edema

Objective The primary objective was to test the hypothesis that clinical re-expansion pulmonary edema is predominantly due to increased permeability of the alveolar-capillary barrier. A secondary objective was to determine if the alveolar epithelium was functionally intact in patients with re-expansion pulmonary edema by measuring net alveolar epithelial fluid transport in a subset of patients.Design Retrospective study of mechanically ventilated patients with re-expansion pulmonary edema.Setting Two academic tertiary care hospitals.Patients Seven patients with acute onset of re-expansion pulmonary edema after tube thoracostomy or thoracentesis.Interventions Pulmonary edema fluid and plasma were collected at the time of onset of re-expansion edema.Measurements and results Contrary to our hypothesis, the mean initial edema fluid to plasma protein ratio was 0.58±0.21, supporting a hydrostatic mechanism of edema formation. Four of the patients had an initial edema fluid to plasma protein ratio of less than 0.65, consistent with pure hydrostatic pulmonary edema, while the others had a slight increase in permeability (edema fluid to plasma ratios of 0.67, 0.71 and 0.77), perhaps due to capillary stress failure from hydrostatic stress. Alveolar fluid clearance (mean 9.8±8.0%/h) was intact in the subset of three patients in whom it was measured.Conclusions This study provides the first direct evidence that hydrostatic forces may contribute to the development of re-expansion pulmonary edema.This study was supported by NIH HL51856 (MAM) and NIH HL70521 (LBW)     

Response to chronic leukapheresis procedures and survival of chronic myelogenous leukemia patients

Cytoreduction of leukemic leukocytosis by continuous flow centrifugation was used in an intermittent or intensive schedule as primary therapy for an average of sixteen months for management of fifteen patients with chronic myelogenous leukemia. The clinical responses and subsequent survival of the patients was studied. Hematologic and chemical changes related to the procedures and the multiple infusions of the sedimenting agent, hydroxyethyl starch, were also studied. This mode of primary therapy offered no survival advantages to patients. There were no adverse effects of the repeated use of the sedimenting agent observed.     

CD^＋34干／祖细胞与纤维连接蛋白的粘附在慢性粒细胞白血？…

探讨ＣＤ＾＋３４干／祖细胞与纤维连接蛋白（ＦＮ）的粘附在慢性粒细胞白血病（ＣＭＬ）发病中的作用。方法①采用细胞术双标记法检测初治ＣＭＬ慢性期３０例正常骨髓１０份ＣＤ＾＋３４细胞上整合素β１链（ＣＤ２９）和α４链（ＣＤ４９ｄ）的表达;②结晶紫染色法观察免疫磁珠分选的ＣＭＬ慢性期５例和５名正常人骨髓ＣＤ＾＋３４细胞ＦＮ的粘附功能;③极限稀释液体微培养观察ＦＮ对正常和ＣＭＬ慢性期骨髓粒细胞－巨噬细胞祖细     

BCR／ABLDCDF—FISH信号特征与染色体核型的关系及其在慢性粒细胞白血病中的意义

目的探讨慢性粒细胞白血病（CML）BCR／ABL DCCF—FISH的信号特点及其与染色体核型的关系。结果使用BCR／ABL的DCDF探针对65例慢性粒细胞白血病骨髓标本进行荧光原位杂交及染色体核型检查。结果65例CML核型43例Ph阳性,1例阴性,其余21例未行核性检查或无可分析分裂相;FISH结果65例均为BCR／ABL阳性,其中9例伴ASS基因缺失,5例复杂易位,1例＋Ph伴ASS基因缺失。结论传统核型与DCDF-FISH,应互相结合,方可对遗传学特征作出更准确分析。     

建立BCR-ABL逆转录病毒介导的小鼠慢性粒细胞白血病模型的实验条件优化

目的探讨构建BCR-ABL逆转录病毒介导的小鼠慢性粒细胞白血病模型最佳实验条件,以简化实验过程、节约成本并提高建模成功率。方法不同剂量5-氟脲嘧啶(5-FU)注射受体鼠后观察骨髓中原始细胞占有核细胞百分比;纤维连接蛋白(FN)铺板后观察逆转录病毒感染效率的变化;分别用不同数量的骨髓细胞(0.2～0.6)×10~6个进行移植后通过形态学观察和荧光原位杂交技术(fluorescence in situ hybtidization,FISH)鉴定移植小鼠成模状况。结果研究剂量范围内5-FU量不影响骨髓原始细胞相对数量;纤维连接蛋白铺板后可使活细胞数量增加30%～50%,感染效率提高10%～20%;移植0.5×10~6个成功感染了BCR-ABL逆转录病毒的供体鼠骨髓细胞入受体小鼠即可成功建模。结论优化后的实验条件简化了程序,节约了成本,大大提高了建模成功率,为相关研究提供了良好的实验参考。     

Telomerase inhibition by retinoids precedes cytodifferentiation of leukemia cells and may contribute to terminal differentiation

Human promyelocytic leukemia HL60 cells display high telomerase activity, a phenotype related to their immortal status. All-trans retinoic acid (ATRA) is a clinically effective cytodifferentiating agent. To understand the mechanism underlying ATRA-induced cytodifferentiation, we did a kinetic analysis of the role of ATRA in inhibiting telomerase in HL60 cells. Our studies indicate that telomerase inhibition by ATRA occurred relatively early after treatment of HL60 cells due to a rapid decrease in hTERT gene expression. More importantly, however, we found through monitoring the expression of CD11b, a marker for granulocytic differentiation of HL60 cells, that down-regulation of telomerase preceded the differentiation of HL60 cells. These observations suggest that the hTERT gene may be a primary target of ATRA regulation of cellular differentiation and the antileukemia activity of ATRA may be mediated by its ability to induce the differentiation of the promyelocytic leukemia cells through down-regulation of the hTERT gene.     

慢性粒细胞白血病患者骨髓来源Flk1~+CD31~-CD34~-间充质干细胞中BCR/ABL融合基因的检测

背景:免疫表型为Flk1+CD31-CD34-的间充质干细胞体内外实验研究均证实在单细胞水平可以向造血及内皮细胞分化。目的:观察慢性粒细胞白血病患者骨髓BCR/ABL融合基因的表达情况。方法:体外培养扩增慢性粒细胞白血病患者骨髓来源原始间充质干细胞,测定其生长曲线,分析其细胞周期及免疫表型,使用RT-PCR和FISH的方法检测其BCR/ABL融合基因的表达情况。结果与结论:慢性粒细胞白血病患者骨髓来源的原始间充质干细胞呈成纤维样生长,大部分细胞处于G0/G1期,并且高表达Flk1,CD13,CD29,CD44,用RT-PCR和FISH的方法能够检测出BCR/ABL融合基因的表达。提出慢性粒细胞白血病的白血病基因转化可能发生在比造血干细胞更高的血液血管干细胞水平上。     

Evidence that spinal astrocytes but not microglia contribute to the pathogenesis of Paclitaxel-induced painful neuropathy

Paclitaxel often induces persistent painful neuropathy as its most common treatment-limiting side effect. Little is known concerning the underlying mechanisms. Given the prominent role of glial cells in many types of neuropathic pain, we investigated here the morphological and functional changes of spinal astrocytes and microglia in a rat model of paclitaxel-induced neuropathy. Immunohistochemistry, western blotting, and real-time polymerase chain reaction were performed with samples from 109 rats up to 28 days after paclitaxel treatment. Paclitaxel (2 mg/kg, i.p.) induced a rapid and persistent activation of spinal astrocytes assessed using glial fibrillary acidic protein, but not apparent activation of microglia assessed using OX42, Iba-1, and phosphorylated p38. In the context of astocyte activation, there was a significant downregulation of glial glutamate transporters GLAST and GLT-1 in spinal dorsal horn. The activation of spinal astrocytes by paclitaxel was not associated with expression of pro-inflammatory cytokines including tumor necrosis factor-α, interleukin-1β, or interleukin-6 in spinal dorsal horn. Systemic treatment with minocycline (50 mg/kg, i.p.) prevented activation of astrocytes and downregulation of glial glutamate transporters in spinal dorsal horn induced by paclitaxel. These data suggest the involvement of spinal astrocytes but not microglia in the pathogenesis of paclitaxel-induced neuropathy. PERSPECTIVE: Spinal astrocytes and/or glial glutamate transporters could be new therapeutic targets for paclitaxel-induced painful neuropathy.     

慢性粒细胞白血病病人Mcl一1基因和Bcr／Abl基因的表达及临床意义

目的探讨慢性粒细胞白血病（CML）病人Mcl—l基因和Bcr／Abl融合基因的表达水平及临床意义。方法应用实时荧光定量PCR技术检测了4l例cML病人（包括慢性期15倒、加速期6例、急变期6例、伊马替尼治疗后遗传学完全缓解8例及非伊马替尼治疗的未缓解的CML病人6例）骨髓标本Mel—l基因、Ber／Abl融合基因的表达水平,以10例正常人作为对照。结果CML各组Mcl—I和Bcr／AblmRNA的表达水平差异均有显著性（X2=19．12—36．08,P〈0．05）。伊马替尼治疗组与正常对照组Mel—lmRNA的表达明显低于其他各组（z=2．547—3．254,P〈0．05）;加速期、急变期及非伊马替尼治疗组之间Mcl—lmRNA的表达水平差异无显著性（z=0．481一1．922,P〉0．05）,但均明显高于慢性期（z=2．65—3．465,P〈0．05）。Ber／AblmRNA在慢性期、加速期、急变期及非伊马替尼治疗组之间表达差异无显著性（z=0．48—1．196,P〉0．05）。CML患者Mel—l与Bcr／AblmRNA的表达水平呈正相关（r=0．68,P〈0．05）。结论Mcl—l和Ber／Abl与CML的病情密切相关,参与cML的发生和发展,是判断病情进展及预后的分子标记物。     

RQ-PCR在慢性粒细胞白血病细胞BCR-ABL融合基因检测中的应用

目的探讨采用实时荧光定量逆转录聚合酶链反应(RQ-PCR)技术检测慢性粒细胞白血病(CML)细胞的BCRABLp210融合基因的临床价值。方法应用RQ-PCR技术对60例CML患者骨髓细胞BCR-ABLp210融合基因进行定量检测分析。结果 60例BCR-ABLp210融合基因阳性的CML患者中,慢性期33例,加速期13例,急变期14例,且CML急变期患者BCR-ABLp210转录本水平明显高于慢性期和加速期患者。经异基因造血干细胞移植治疗或经伊马替尼治疗6个月后,BCRABLp210转录本水平均较6个月前明显降低。但这两种方法治疗CML患者12个月后的效果比较差异无统计学意义(P0.05),而采用其他酪氨酸激酶抑制剂治疗CML 12个月后也可达到相似的治疗效果。结论 RQ-PCR技术监测CML患者细胞BCR-ABLp210融合基因表达有助于CML的诊断、治疗效果评价及微小残留的监测。     

Proteasome inhibition leads to significant reduction of Bcr-Abl expression and subsequent induction of apoptosis in K562 human chronic myelogenous leukemia cells

The chimeric oncogene bcr-abl is detected in virtually every case of chronic myelogenous leukemia. It has been shown that cells (such as K562) expressing Bcr-Abl/p210, a protein tyrosine kinase, not only undergo cellular transformation but also demonstrate multiple drug resistance. Recent studies also demonstrate that the proteasome is involved in the survival signaling pathway(s). In the current study, we tested the hypothesis that the proteasome might play a role in regulating Bcr-Abl function. We have demonstrated by using a variety of inhibitors that inhibition of the proteasome, but not of the cysteine protease, activity is able to activate the apoptotic cell death program in K562 cells. Proteasome inhibition-induced apoptosis is demonstrated by condensation and fragmentation of nuclei, appearance of an apoptotic population with sub-G1 DNA content, the internucleosomal fragmentation of DNA, and cleavage of poly(ADP-ribose) polymerase, and can be blocked by a specific caspase-3-like tetrapeptide inhibitor. Western blot analysis with specific antibodies to c-Abl and Bcr proteins show that treatment of K562 cells with a proteasome inhibitor results in significant reduction of Bcr-Abl protein expression, which occurs several hours before the onset of apoptotic execution. Levels of c-Abl/p145 and Bcr/p160 proteins, however, remain essentially unaltered at that time. Furthermore, reduced Bcr-Abl expression is reflected in significantly attenuated Bcr-Abl-mediated protein tyrosine phosphorylation. Taken together, these results indicate that proteasome inhibition is sufficient to inactivate Bcr-Abl function and subsequently activate the apoptotic death program in cells that are resistant to apoptosis induced by chemotherapy.     

bcl—2基因表达在慢性粒细胞白血病急变中的意义

目的探讨ｂｃｌ２基因表达在慢性粒细胞白血病（ＣＭＬ）急变中的生物学意义。方法采用碱性磷酸酶抗碱性磷酸酶免疫复合物方法和地高辛标记探针原位杂交技术检测各期ＣＭＬ患者６０例新鲜骨髓标本中ＢＣＬ２蛋白和ｂｃｌ２ｍＲＮＡ的表达,并对其中１９例标本进行流式细胞术分析骨髓细胞凋亡率及细胞周期。结果初诊和治疗后ＣＭＬ中ｂｃｌ２基因表达相近,但明显低于急变时。ｂｃｌ２ｍＲＮＡ表达与蛋白表达基本一致。ｂｃｌ２基因高表达与ＣＭＬ患者外周血血红蛋白、血小板、幼稚细胞及骨髓不成熟细胞比例相关。加速／急变期ＣＭＬ细胞凋亡率明显低于慢性期,但细胞周期无明显变化。结论ＣＭＬ急变时ｂｃｌ２基因表达增高,骨髓细胞凋亡率降低,这些现象部分地阐明了ＣＭＬ急变预后不良的机制,也为ＣＭＬ急变的早期诊断和治疗提供了实验依据。     

Interferon-alpha restores the deficient expression of the cytoadhesion molecule lymphocyte function antigen-3 by chronic myelogenous leukemia progenitor cells.

Hematopoietic cells from the malignant clone in chronic myelogenous leukemia (CML) maintain and expand a proliferative advantage over normal hematopoietic cells within the bone marrow. This advantage is often ameliorated or reversed in vivo by IFN alpha. Based upon earlier studies suggesting decreased adhesiveness of CML progenitor cells, we asked whether CML progenitor cells are deficient in their expression of the cytoadhesion molecule lymphocyte function antigen-3 (LFA-3, CD58) which is normally expressed on hematopoietic progenitors. Progenitor cells from untreated CML patients showed greatly reduced or absent LFA-3 expression, whereas progenitors from patients treated with IFN alpha in vivo or in vitro expressed surface LFA-3 at more normal levels. LFA-3-deficient CML progenitor cells were unable to stimulate normal regulatory proliferative responses in autologous T cells. We hypothesize that IFN alpha-sensitive LFA-3 deficiency reflects a cell surface cytoadhesion defect which may help explain adhesive abnormalities of CML progenitor cells in vitro and clonal proliferation in vivo.     

Dasatinib: a tyrosine kinase inhibitor for the treatment of chronic myelogenous leukemia and philadelphia chromosome-positive acute lymphoblastic leukemia

BACKGROUND: The Philadelphia chromosome is formed from a translocation of genetic material involving human chromosomes 9 and 22. The resulting gene product, BCR-ABL, encodes for an abnormal tyrosine kinase (TK) that is a factor in the pathology of chronic myelogenous leukemia (CML). Use of targeted therapy that inhibits BCR-ABL kinase activity may lead to hematologic and cytogenetic responses in affected individuals. The oral TK inhibitor dasatinib was approved in 2006 for use in patients with CML or Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL) who are unable to tolerate or have not responded to other treatments. OBJECTIVE: This paper reviews the available data on dasatinib, including its pharmacokinetic and pharmacodynamic properties, findings of in vitro and in vivo studies, adverse effects, and potential place in therapy. METHODS: Pertinent information was identified through searches of MEDLINE (1966-May 2007), EMBASE (1980-first quarter 2007), and International Pharmaceutical Abstracts (1970-May 2007) using the terms dasatinib, BMS-354825, chronic myelogenous leukemia, Sprycel, Philadelphia chromosome, and acute lymphoblastic leukemia. All clinical studies and case reports published at the time of the search were included in this review. RESULTS: Observed mutations in the amino acid sequence of BCR-ABL cause the failure of treatment with existing TK inhibitors. Dasatinib has shown in vitro and in vivo activity against BCR-ABL, including mutations that are resistant to other available TK inhibitors. Preliminary results are available from several noncomparative studies of dasatinib in patients who were unable to tolerate or were resistant to previous therapies. The 5 phases of START (SRC/ABL Tyrosine kinase inhibition Activity Research Trials of dasatinib) represent the largest and most comprehensive evaluation of dasatinib in the treatment of patients in all stages of CML or Philadelphia chromosome-positive ALL who had undergone previous treatment for leukemia. Dasatanib had the greatest benefit in patients in the chronic phase of CML, with complete hematologic responses in 90% of patients, 52% of whom achieved a major hematologic response. Compared with those in the chronic phase, patients in the accelerated phase or blast crisis of CML, or with Philadelphia chromosome-positive ALL had lower responses. In the START-R trial, which compared the response to dasatinib and high-dose imatinib (800 mg/d), both regimens had comparable ability to induce a complete hematologic response (95% and 93%, respectively), although more patients achieved a major cytogenetic response with dasatinib (32% vs 7%). Adverse effects include significant myelosuppression. Dasatinib may have the potential for use in the management of nonleukemic malignancies. CONCLUSIONS: Dasatinib has a wider spectrum of activity against a broader range of BCR-ABL forms than existing TK inhibitors. It has shown clinical benefit and tolerability in patients in all phases of CML, as well as in those with Philadelphia chromosome-positive ALL. Dasatinib illustrates the potential for targeted drug development based on an understanding of the genetic alterations leading to CML and the development of resistance to treatment.     

Biological validation of differentially expressed genes in chronic lymphocytic leukemia identified by applying multiple statistical methods to oligonucleotide microarrays

Oligonucleotide microarrays are a powerful tool for profiling the expression levels of thousands of genes. Different statistical methods for identifying differentially expressed genes can yield different results. To our knowledge, no experimental test has been performed to decide which method best identifies genes that are truly differentially expressed. We applied three statistical methods (dChip, t-test on log-transformed data, and Wilcoxon test) to identify differentially expressed genes in previously untreated patients with chronic lymphocytic leukemia (CLL). We used a training set of Affymetrix Hu133A microarray data from 11 patients with unmutated immunoglobulin (Ig) heavy chain variable region (VH) genes and 8 patients with mutated Ig VH genes. Differential expression was validated using semiquantitative real-time polymerase chain reaction assays and by validating models to predict the somatic mutation status of an independent test set of nine CLL samples. The methods identified 144 genes that were differentially expressed between cases of CLL with unmutated compared with mutated Ig VH genes. Eighty genes were identified by Wilcoxon test, 60 by t-test, and 65 by dChip, but only 11 were identified by all three methods. Greater agreement was found between the t-test and the Wilcoxon test. Differential expression was validated by semiquantitative real-time polymerase chain reaction assays for 83% of individual genes, regardless of the statistical method. However, the Wilcoxon test gave the most accurate predictions on new samples, and dChip, the least accurate. We found that all three methods were equally good for finding differentially expressed genes, but they found different genes. The genes selected by the nonparametric Wilcoxon test are the most robust for predicting the status of new cases. A comprehensive list of all differentially expressed genes can only be obtained by combining the results of multiple statistical tests.     

微卫星Mfd41和DCC的遗传不稳定性与慢性粒细胞白血病病程发展关系研究

目的：研究微卫星ＤＮＡｓ的遗传不稳定性与慢性粒细胞白血病（ＣＭＬ）加速、急变的关系。方法：采用基础ＰＣＲ银染方法对９例加速期和８例急变期ＣＭＬ患者的骨髓细胞与其慢性期标本位于染色体１７ｐ的Ｍｆｄ４１和１８ｑ的ＤＣＣ两个微卫星序列进行比较分析。结果：１７例ＣＭＬ加速期或急变期患者中有８例出现微卫星不稳定性（ＭＳＩ）或杂合性丢失（ＬＯＨ），占总病例数的４７．５％。６例（加速期２例，急变期４例）出现ＤＣＣ改变，占总病例数的３５．３％；２例（加速期和急变期各１例）出现Ｍｆｄ４１改变，占总病例数的１１．８％。结论：微卫星ＤＮＡｓ的遗传不稳定性可能参与ＣＭＬ加速或急变的演变     

Mechanisms underlying abnormal trafficking of malignant progenitors in chronic myelogenous leukemia. Decreased adhesion to stroma and fibronectin but increased adhesion to the basement membrane components laminin and collagen type IV.

We studied the adhesion of primitive and committed progenitors from chronic myelogenous leukemia (CML) and normal bone marrow to stroma and to several extracellular matrix components. In contrast to benign primitive progenitors from CML or normal bone marrow, Ph1-positive primitive progenitors from CML bone marrow fail to adhere to normal stromal layers and to fibronectin and its proteolytic fragments, but do adhere to collagen type IV, an extracellular matrix component of basement membranes. Similarly, multilineage colony-forming unit (CFU-MIX) progenitors from CML bone marrow do not adhere to fibronectin or its adhesion promoting fragments but adhere to collagen type IV. Unlike committed progenitors from normal bone marrow, CML single-lineage burst-forming units-erythroid and granulocyte/macrophage colony-forming units fail to adhere to fibronectin or its components but do adhere to both collagen type IV and laminin. Evaluation of adhesion receptor expression demonstrates that fibronectin receptors (alpha 4, alpha 5, and beta 1) are equally present on progenitors from normal and CML bone marrow. However, a fraction of CML progenitors express alpha 2 and alpha 6 receptors, associated with laminin and collagens, whereas these receptors are absent from normal progenitors. These observations indicate that the premature release of malignant Ph1-positive progenitors into the circulation may be caused by loss of adhesive interactions with stroma and/or fibronectin and acquisition of adhesive interactions with basement membrane components. Further study of the altered function of cell-surface adhesion receptors characteristic of the malignant clone in CML may lead to a better understanding of the mechanisms underlying both abnormal expansion and abnormal circulation of malignant progenitors in CML.     

CD34+干/祖细胞与纤维连接蛋白的粘附在慢性粒细胞白血病发病中的意义

目的探讨CD34 干／祖细胞与纤维连接蛋白（FN）的粘附在慢性粒细胞白血病（CML）发病中的作用。方法①采用流式细胞术双标记法检测初治CML慢性期30例和正常骨髓10份CD34 细胞上整合素β1链（CD29）和α4链（CD49d）的表达;②结晶紫染色法观察免疫磁珠分选的CML慢性期5例和5名正常人骨髓CD34 细胞与FN的粘附功能;③极限稀释液体微培养观察FN对正常和CML慢性期骨髓粒细胞-巨噬细胞祖细胞集落（CFU－GM）形成能力的影响。结果①CML慢性期骨髓CD34 细胞CD29和CD49d的表达与正常骨髓比较,差异无显著性;②CML骨髓CD34 细胞与FN的粘附明显低于正常（P＜0．01）;③FN显著抑制正常骨髓CFU-GM的形成（P＜0．01）,而对CML骨髓CFU-GM的形成无显著影响。结论CML骨髓CD34 干／祖细胞与FN的粘附功能减弱,因而缺乏FN对祖细胞增殖的调节作用是CML髓系扩增的原因之一。