285 research outputs found
Further evidence for association of hepatitis C infection with parenteral schistosomiasis treatment in Egypt
BACKGROUND: Hepatitis C virus (HCV) infection and schistosomiasis are major public health problems in the Nile Delta of Egypt. To control schistosomiasis, mass treatment campaigns using tartar emetic injections were conducted in the 1960s through 1980s. Evidence suggests that inadequately sterilized needles used in these campaigns contributed to the transmission of HCV in the region. To corroborate this evidence, this study evaluates whether HCV infections clustered within houses in which household members had received parenteral treatment for schistosomiasis. METHODS: A serosurvey was conducted in a village in the Nile Delta and residents were questioned about prior treatment for schistosomiasis. Sera were evaluated for the presence of antibodies to HCV. The GEE2 approach was used to test for clustering of HCV infections, where correlation of HCV infections within household members who had been treated for schistosomiasis was the parameter of interest. RESULTS: A history of parenteral treatment for schistosomiasis was observed to cluster within households, OR for clustering: 2.44 (95% CI: 1.47–4.06). Overall, HCV seropositivity was 40% (321/796) and was observed to cluster within households that had members who had received parenteral treatment for schistosomiasis, OR for clustering: 1.76 (95% CI: 1.05–2.95). No such evidence for clustering was found in the remaining households. CONCLUSION: Clustering of HCV infections and receipt of parenteral treatment for schistosomiasis within the same households provides further evidence of an association between the schistosomiasis treatment campaigns and the high HCV seroprevalence rates currently observed in the Nile delta of Egypt
Mutations in ASXL1 are associated with poor prognosis across the spectrum of malignant myeloid diseases
The ASXL1 gene is one of the most frequently mutated genes in malignant myeloid diseases. The ASXL1 protein belongs to protein complexes involved in the epigenetic regulation of gene expression. ASXL1 mutations are found in myeloproliferative neoplasms (MPN), myelodysplastic syndromes (MDS), chronic myelomonocytic leukemia (CMML) and acute myeloid leukemia (AML). They are generally associated with signs of aggressiveness and poor clinical outcome. Because of this, a systematic determination of ASXL1 mutational status in myeloid malignancies should help in prognosis assessment
Combined mutations of ASXL1, CBL, FLT3, IDH1, IDH2, JAK2, KRAS, NPM1, NRAS, RUNX1, TET2 and WT1 genes in myelodysplastic syndromes and acute myeloid leukemias
<p>Abstract</p> <p>Background</p> <p>Gene mutation is an important mechanism of myeloid leukemogenesis. However, the number and combination of gene mutated in myeloid malignancies is still a matter of investigation.</p> <p>Methods</p> <p>We searched for mutations in the <it>ASXL1, CBL, FLT3, IDH1, IDH2, JAK2, KRAS, NPM1, NRAS, RUNX1, TET2 </it>and <it>WT1 </it>genes in 65 myelodysplastic syndromes (MDSs) and 64 acute myeloid leukemias (AMLs) without balanced translocation or complex karyotype.</p> <p>Results</p> <p>Mutations in <it>ASXL1 </it>and <it>CBL </it>were frequent in refractory anemia with excess of blasts. Mutations in <it>TET2 </it>occurred with similar frequency in MDSs and AMLs and associated equally with either <it>ASXL1 </it>or <it>NPM1 </it>mutations. Mutations of <it>RUNX1 </it>were mutually exclusive with <it>TET2 </it>and combined with <it>ASXL1 </it>but not with <it>NPM1</it>. Mutations in <it>FLT3 (</it>mutation and internal tandem duplication), <it>IDH1</it>, <it>IDH2</it>, <it>NPM1 </it>and <it>WT1 </it>occurred primarily in AMLs.</p> <p>Conclusion</p> <p>Only 14% MDSs but half AMLs had at least two mutations in the genes studied. Based on the observed combinations and exclusions we classified the 12 genes into four classes and propose a highly speculative model that at least a mutation in one of each class is necessary for developing AML with simple or normal karyotype.</p
WHO-defined ‘myelodysplastic syndrome with isolated del(5q)' in 88 consecutive patients: survival data, leukemic transformation rates and prevalence of JAK2, MPL and IDH mutations
The 2008 World Health Organization (WHO) criteria were used to identify 88 consecutive Mayo Clinic patients with ‘myelodysplastic syndrome with isolated del(5q)' (median age 74 years; 60 females). In all, 60 (68%) patients were followed up to the time of their death. Overall median survival was 66 months; leukemic transformation was documented in five (5.7%) cases. Multivariable analysis identified age ⩾70 years (P=0.01), transfusion need at diagnosis (P=0.04) and dysgranulopoiesis (P=0.02) as independent predictors of shortened survival; the presence of zero (low risk), one (intermediate risk) or ⩾2 (high risk) risk factors corresponded to median survivals of 102, 52 and 27 months, respectively. Janus kinase 2 (JAK2), thrombopoietin receptor (MPL), isocitrate dehydrogenase 1 (IDH1) and IDH2 mutational analysis was performed on archived bone marrows in 78 patients; JAK2V617F and MPLW515L mutations were shown in five (6.4%) and three (3.8%) patients, respectively, and did not seem to affect phenotype or prognosis. IDH mutations were not detected. Survival was not affected by serum ferritin and there were no instances of death directly related to iron overload. The current study is unique in its strict adherence to WHO criteria for selecting study patients and providing information on long-term survival, practical prognostic factors, baseline risk of leukemic transformation and the prevalence of JAK2, MPL and IDH mutations
Persistence of Plasmodium falciparum parasitemia after artemisinin combination therapy: evidence from a randomized trial in Uganda
Artemisinin resistance is rapidly spreading in Southeast Asia. The efficacy of artemisinin-combination therapy (ACT) continues to be excellent across Africa. We performed parasite transcriptional profiling and genotyping on samples from an antimalarial treatment trial in Uganda. We used qRT-PCR and genotyping to characterize residual circulating parasite populations after treatment with either ACT or ACT-primaquine. Transcripts suggestive of circulating ring stage parasites were present after treatment at a prevalence of >25% until at least 14 days post initiation of treatment. Greater than 98% of all ring stage parasites were cleared within the first 3 days, but subsequently persisted at low concentrations until day 14 after treatment. Genotyping demonstrated a significant decrease in multiplicity of infection within the first 2 days in both ACT and ACT-primaquine arms. However, multiple clone infections persisted until day 14 post treatment. Our data suggest the presence of genetically diverse persisting parasite populations after ACT treatment. Although we did not demonstrate clinical treatment failures after ACT and the viability and transmissibility of persisting ring stage parasites remain to be shown, these findings are of relevance for the interpretation of parasite clearance transmission dynamics and for monitoring drug effects in Plasmodium falciparum parasites
Recurrent DNMT3A R882 Mutations in Chinese Patients with Acute Myeloid Leukemia and Myelodysplastic Syndrome
Somatic mutations of DNMT3A gene have recently been reported in acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). We examined the entire coding sequences of DNMT3A gene by high-resolution melting analysis and sequencing in Chinese patients with myeloid malignancies. R882 mutations were found in 12/182 AML and in 4/51 MDS, but not in either 79 chronic myeloid leukemia (CML), or 57 myeloproliferative neoplasms (MPNs), or 4 chronic monomyelocytic leukemia. No other DNMT3A mutations were detected in all patients. R882 mutations were associated with old age and more frequently present in monoblastic leukemia (M4 and M5, 7/52) compared to other subtypes (5/130). Furthermore, 14/16 (86.6%) R882 mutations were observed in patients with normal karyotypes. The overall survival of mutated MDS patients was shorter than those without mutation (median 9 and 25 months, respectively). We conclude that DNMT3A R882 mutations are recurrent molecular aberrations in AML and MDS, and may be an adverse prognostic event in MDS
Tet2 disruption leads to enhanced self-renewal and altered differentiation of fetal liver hematopoietic stem cells
Somatic mutation of ten-eleven translocation 2 (TET2) gene is frequently found in human myeloid malignancies. Recent reports showed that loss of Tet2 led to pleiotropic hematopoietic abnormalities including increased competitive repopulating capacity of bone marrow (BM) HSCs and myeloid transformation. However, precise impact of Tet2 loss on the function of fetal liver (FL) HSCs has not been examined. Here we show that disruption of Tet2 results in the expansion of Lin−Sca-1+c-Kit+ (LSK) cells in FL. Furthermore, Tet2 loss led to enhanced self-renewal and long-term repopulating capacity of FL-HSCs in in vivo serial transplantation assay. Disruption of Tet2 in FL also led to altered differentiation of mature blood cells, expansion of common myeloid progenitors and increased resistance for hematopoietic progenitor cells (HPCs) to differentiation stimuli in vitro. These results demonstrate that Tet2 plays a critical role in homeostasis of HSCs and HPCs not only in the BM, but also in FL
Mutations with epigenetic effects in myeloproliferative neoplasms and recent progress in treatment: Proceedings from the 5th International Post-ASH Symposium
Immediately following the 2010 annual American Society of Hematology (ASH) meeting, the 5th International Post-ASH Symposium on Chronic Myelogenous Leukemia and BCR-ABL1-Negative Myeloproliferative Neoplasms (MPNs) took place on 7–8 December 2010 in Orlando, Florida, USA. During this meeting, the most recent advances in laboratory research and clinical practice, including those that were presented at the 2010 ASH meeting, were discussed among recognized authorities in the field. The current paper summarizes the proceedings of this meeting in BCR-ABL1-negative MPN. We provide a detailed overview of new mutations with putative epigenetic effects (TET oncogene family member 2 (TET2), additional sex comb-like 1 (ASXL1), isocitrate dehydrogenase (IDH) and enhancer of zeste homolog 2 (EZH2)) and an update on treatment with Janus kinase (JAK) inhibitors, pomalidomide, everolimus, interferon-α, midostaurin and cladribine. In addition, the new ‘Dynamic International Prognostic Scoring System (DIPSS)-plus' prognostic model for primary myelofibrosis (PMF) and the clinical relevance of distinguishing essential thrombocythemia from prefibrotic PMF are discussed
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