Research Progress on role of Abnormal Tryptophan Metabolism in Immune Thrombocytopenia / 中国实验血液学杂志

Immune thrombocytopenia (ITP) is a common acquired autoimmune hematological disorders. Platelet autoantibodies lead to the decrease of platelet production and (or) increase of its destruction. The latest researches showed that the abnormal tryptophan metabolism mediated by indoleamine-2, 3-dioxygenase(IDO) is related with the pathogenesis of ITP. The patients with ITP show less expression of IDO, reduction of Treg cells and increase of autoreactive T cells and autoantibodies. CTLA-4-Ig can improve the expression of IDO in the patients with ITP, which also can inhibit the proliferation and activation of self-reactive T cells. Thus, clarifying the abnormal tryptophan metabolism mediated by IDO may provide a new idea for improving the understand of the pathogenesis and treatment of ITP. This review focuses on reasearch progress of the tryptophan metabolism mediated by IDO and ITP.

Relationship between polymorphisms of tumor necrosis factor alpha gene and primary myelodysplastic syndromes / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the association of single nucleus polymorphisms(SNP)of tumor necrosis factor alpha (TNF-α) gene (-308 G>A and -238 G>A genotypes) with susceptibility to primary myelodysplastic syndromes (MDS).</p><p><b>METHODS</b>Two SNPs (TNF-α-308 G>A,TNF-α-238 G>A) of TNF-α gene were detected by Taqman probes in 341 MDS patients and 365 unrelated-healthy controls.</p><p><b>RESULTS</b>Compared to healthy controls, the frequency of TNF-α-308 AA+AG genotype and A allele increased (18% vs 10%, P=0.015, 9% vs 5%, P=0.021, respectively) in refractory cytopenia with multilineage dysplasia (RCMD) patients. There was no correlation of TNF-α-308 G>A genotype and allele frequency between MDS and controls. No difference in the genotype and allele frequency of TNF-α-238 G>A were found between controls and MDS or the subtypes of MDS (P>0.05). We did not find any linkage between plasma level of TNF-α and TNF-α-308 G>A or TNF-α-238 G>A genotype. Statistic differences were observed between platelet count[58(1-611)×10⁹/L vs 90(7-352)×10⁹/L]and bone marrow blasts in MDS patients carrying TNF-α-308 G>A GG and AA+AG genotype (P=0.024, 0.019, respectively).</p><p><b>CONCLUSION</b>TNF-α-308 G>A polymorphism was correlated with susceptibility to MDS-RCMD.</p>

Analysis on 71 patients with polycythemia vera / 中国实验血液学杂志

The aim of this study was to analyse the clinical characteristics and laboratory data, treatment and prognosis of polycythemia vera (PV). A retrospective study was performed for 71 PV patients treated in our hospital during January 2001 to July 2011 including analysis of clinical characteristics, laboratory data, myelogram chromosome karyotypes, BCR/ABL and JAK2V617F genes, as well as lactate dehydrogenase (LDH) and neuron-specific enolase (NSE) levels in serum and so on. The results showed that 71 patients (37 males and 34 females with a average age of 57.8 years) were diagnosed. Thrombosis and embolism occurred in 34 patients (47.89%), hemorrhage in 10 patients (14.08%), splenomegaly occurred in 44 patients. The onset of the disease was insidious, 13 patients (18.31%) were found to have PV during the treatments for other diseases. The average hemoglobin at diagnosis was 206.31 (171 - 242) g/L. JAK2V617F mutation was detected in 31 (81.58%) of 38 patients studied. The average levels of serum LDH and NSE were higher than normal and both positively correlated with hemoglobin (P = 0.007, P = 0.005). The disease outcomes were myelofibrosis for 3 patients, death from cerebral hemorrhage for 1 patient, and death from ineffective chemotherapy in 1 patient with ANLL-M2. It is concluded that PV is a chronic myeloproliferative disorder characterized predominantly by thrombosis and hemorrhage. The serum LDH and NSE levels are higher than the normal values. It is inferred that the serum LDH and NSE levels can reflect the degree of malignant proliferation of bone marrow hematopoietic cells and also can be used as an indicator to judge the therapeutic effect of PV.

JAK2 exon 12 mutations in patients with Philadelphia (Ph) chromosome-negative myeloproliferative neoplasms / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate JAK2 exon 12 mutations in patients with Philadelphia (Ph) chromosome-negative myeloproliferative neoplasms (MPN) and the clinical characteristics of patients with JAK2 exon 12 mutants.</p><p><b>METHODS</b>Allele-specific PCR (AS-PCR) was applied to identify JAK2 V617F mutation. Genomic DNA corresponding to exon 12 of JAK2 gene and epigenetic regulator gene (TET2, ASXL1, EZH2) were amplified by polymerase chain reaction (PCR). Identification of mutants was by direct sequencing and classification of mutation types by sequencing followed by plasmid cloning. SNP genotyping of two 46/1 tag SNPs, rs12340895 and rs10974944, was analyzed using commercially available Taqman assays on the 7500HT real-time PCR instrument according to standard protocols.</p><p><b>RESULTS</b>No JAK2 exon 12 mutation was detected in patients with ET, PMF or JAK2 V617F positive PV. Among 13 JAK2 V617F negative PV patients, JAK2 exon 12 mutation was detected as N542-E543del in 2(15.4%) patients who presented with a phenotype of predominant erythrocytosis and erythroid colonic grown from their bone marrow samples in the absence of exogenous EPO, reduced serum erythropoietin (EPO) level, and no mutations in TET2, ASXL1 or EZH2 genes. One of the affected patients was heterozygous for 46/1 but the second was negative for this haplotype.</p><p><b>CONCLUSION</b>There was no need to detect JAK2 exon 12 mutation in ET, PMF or MPN-U patients without JAK2 V67F mutation. Ph negative MPN patients with JAK2 exon 12 mutations had somewhat unique clinical and laboratory features.</p>

Diagnosis of aortic intramural hematoma by electron beam CT / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the value of electron beam CT (EBCT) in the diagnosis of aortic intramural hematoma (AIH).</p><p><b>METHODS</b>Twenty-five patients who complained of acute chest and back pain were scanned with an EBCT scanner (Imatron C-150) using contrast-enhanced continuous volume scanning (CVS) for establish the diagnosis of AIH.</p><p><b>RESULTS</b>Seven patients were diagnosed as having Stanford type A, and the others as type B AIH. The direct features of AIH in EBCT included crescent or circular thickening (>5 mm) of the aortic wall without signs of lumen formation resulting from intimal rupture. The indirect features included calcification ingression (7 cases), penetrating ulcer (12 cases), atherosclerosis (18 cases) and leakages (5 cases). The complicating features included pericardial effusion (5 cases), pleural effusion (14 cases), involvement of the large branches (5 cases), aortic dissection (3 cases) and aneurysms (4 cases).</p><p><b>CONCLUSION</b>EBCT can provide important information for the diagnosis and treatment of AIH, and can be useful for follow-up observation of the patients.</p>