Clinical characteristics and symptom burden of Thai myeloproliferative neoplasm patients.

ABSTRACTObjective Patients living with myeloproliferative neoplasms (MPNs) suffer from symptom burden that affect quality of life. Due to the differences in cultures, climates, and genetic background, we aimed to investigate the symptom burden of Thai MPN patients Methods A comprehensive survey using the MPN-10 questionnaire was carried out between September 1, 2014, and September 30, 2017. The scores obtained were then correlated with clinical outcomes.. Results A total of 145 patients were enrolled. Nearly 90% of patients reported being symptomatic. The mean MPN-10 score was 13.6 (SD = 11). The mean MPN-10 score was highest in PMF, whereas the mean score and intensity of individual items were surprisingly low in ET and PV. Notably, the mean MPN-10 score was significantly higher in patients with documented splenomegaly compared to those with a normal-sized spleen. However, there were no correlations between MPN-10 scores and the mutation status, disease complications such as thrombosis and hemorrhage, progression to myelofibrosis or leukemia, and mortality. Patients who needed regular transfusions reported a higher MPN-10 score compared to those who did not. Conclusion The MPN-10 score did not predict survival outcomes among Thai MPN patients. Higher MPN-10 was associated with more transfusion. Thai MPN patients reported lower MPN-10 compared to western population especially PV and ET.

Management of classical Philadelphia chromosome-negative myeloproliferative neoplasms in Asia: consensus of the Asian Myeloid Working Group.

Myeloproliferative neoplasms (MPN) are a heterogeneous group of clonal hematopoietic stem cell disorders characterized clinically by the proliferation of one or more hematopoietic lineage(s). The classical Philadelphia-chromosome (Ph)-negative MPNs include polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). The Asian Myeloid Working Group (AMWG) comprises representatives from fifteen Asian centers experienced in the management of MPN. This consensus from the AMWG aims to review the current evidence in the risk stratification and treatment of Ph-negative MPN, to identify management gaps for future improvement, and to offer pragmatic approaches for treatment commensurate with different levels of resources, drug availabilities and reimbursement policies in its constituent regions. The management of MPN should be patient-specific and based on accurate diagnostic and prognostic tools. In patients with PV, ET and early/prefibrotic PMF, symptoms and risk stratification will guide the need for early cytoreduction. In younger patients requiring cytoreduction and in those experiencing resistance or intolerance to hydroxyurea, recombinant interferon-α preparations (pegylated interferon-α 2A or ropeginterferon-α 2b) should be considered. In myelofibrosis, continuous risk assessment and symptom burden assessment are essential in guiding treatment selection. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) in MF should always be based on accurate risk stratification for disease-risk and post-HSCT outcome. Management of classical Ph-negative MPN entails accurate diagnosis, cytogenetic and molecular evaluation, risk stratification, and treatment strategies that are outcome-oriented (curative, disease modification, improvement of quality-of-life).

Good prognosis of adult hemophagocytic lymphohistiocytosis associated with the germline HAVCR2 mutation.

Hemophagocytic lymphohistiocytosis (HLH) in adults may be idiopathic or secondary to various conditions. Recent studies identified germline hepatitis A virus-cellular receptor 2 (HAVCR2) mutations in subcutaneous panniculitis-like T-cell lymphoma (SPTCL) with HLH. The roles of this mutation in HLH, especially in idiopathic group, have never been explored. Of the 65 HLH cases, we detected germline HAVCR2Y82C mutations in nine (13.8%) cases (five SPTCL and four idiopathic HLH). Other causes of HLH were hematologic malignancies excluding SPTCL (32.3%), idiopathic HLH without HAVCR2 mutation (29.2%), infections (15.3%), and autoimmune diseases (9.2%). Germline HAVCR2 mutation was significantly associated with less anemia and better survival. This defines a distinct subgroup of HLH.

Exploring Toxin Genes of Myanmar Russell's Viper, Daboia siamensis, through De Novo Venom Gland Transcriptomics.

The Russell's viper (Daboia siamensis) is a medically important venomous snake in Myanmar. Next-generation sequencing (NGS) shows potential to investigate the venom complexity, giving deeper insights into snakebite pathogenesis and possible drug discoveries. mRNA from venom gland tissue was extracted and sequenced on the Illumina HiSeq platform and de novo assembled by Trinity. The candidate toxin genes were identified via the Venomix pipeline. Protein sequences of identified toxin candidates were compared with the previously described venom proteins using Clustal Omega to assess the positional homology among candidates. Candidate venom transcripts were classified into 23 toxin gene families including 53 unique full-length transcripts. C-type lectins (CTLs) were the most highly expressed, followed by Kunitz-type serine protease inhibitors, disintegrins and Bradykinin potentiating peptide/C-type natriuretic peptide (BPP-CNP) precursors. Phospholipase A2, snake venom serine proteases, metalloproteinases, vascular endothelial growth factors, L-amino acid oxidases and cysteine-rich secretory proteins were under-represented within the transcriptomes. Several isoforms of transcripts which had not been previously reported in this species were discovered and described. Myanmar Russell's viper venom glands displayed unique sex-specific transcriptome profiles which were correlated with clinical manifestation of envenoming. Our results show that NGS is a useful tool to comprehensively examine understudied venomous snakes.

Germline HAVCR2 mutations and their relation to the clinical spectrum of subcutaneous panniculitis-like T-cell lymphoma and hemophagocytic lymphohistiocytosis: results from a multicenter study and meta-analysis.

Germline HAVCR2 mutations are frequently detected in subcutaneous panniculitis-like T-cell lymphoma (SPTCL) patients with/without hemophagocytic lymphohistiocytosis (HLH) but factors associated with variable manifestations remain undetermined. To evaluate clinical variations and associated factors in SPTCL and/or HLH with/without HAVCR2 mutations, we performed direct sequencing of HAVCR2 exon 2 using DNA from patients with SPTCL or idiopathic HLH/HLH-like systemic illnesses, defined by HLH alone without secondary causes. The systematic review and individual patient data (IPD) level meta-analysis which included the present and previously published studies reporting HAVCR2 mutations in SPTCL with/without HLH populations was subsequently conducted using random-effects meta-analysis and multivariate logistic regression. Among 34 patients enrolled, ten of 28 SPTCL patients developed HLH/HLH-like systemic illnesses. Six cases with HAVCR2Y82C mutation manifested with HLH without panniculitis. Male sex (P=0.03) and age <18 years (P=0.04) were associated with HLH, corresponding to the inverse correlation between age and HLH-2004 score (r=-0.40; P=0.02). Homozygous HAVCR2Y82C mutation was more common in the presence of HLH compared with the absence (75.0% vs. 44.4%; P=0.02). Using IPD from the present and the other three eligible cohorts (N=127), male sex, heterozygous and homozygous/compound heterozygous HAVCR2 mutations were associated with HLH by the adjusted odds ratio of 2.93 (95% confidence interval [CI]: 1.22-7.06), 4.77 (95% CI: 1.05-21.63) and 8.48 (95% CI: 2.98-24.10), respectively. Patients with male sex and/or germline HAVCR2 mutations showed an increased risk of developing HLH. Younger patients tended to manifest with HLH, while older patients typically presented with SPTCL with less frequent HLH/HLH-like systemic illnesses.

The reliability of FEbrile Neutropenia after ChEmotherapy (FENCE) scores in predicting granulocyte colony-stimulating factor breakthrough febrile neutropenia among patients with lymphoma undergoing first-cycle chemotherapy: A prospective observational study.

Background: A tool for estimating risk of febrile neutropenia (FN) after chemotherapy, namely the FEbrile Neutropenia after ChEmotherapy (FENCE) score, has been developed but has not been widely validated. This study aimed to validate the FENCE score as a tool for predicting granulocyte colony-stimulating factor (G-CSF) breakthrough FN among patients with lymphoma who underwent chemotherapy. Methods: This was a prospective observational study of treatment-naive adult patients with lymphoma who underwent their first cycle of chemotherapy between 2020 and 2021. The patients were followed up until the next cycle of chemotherapy to identify any infection events. Results: Among the 135 patients with lymphoma, 62 (50%) were men. In a comparison of the value of each FENCE parameter for predicting G-CSF breakthrough infection, the parameter of advanced-stage disease showed high sensitivity of 92.8%, and receipt of platinum chemotherapy showed high specificity of 95.33%. With a FENCE score of 12 as a cutoff for low risk, analysis across all patients with lymphoma resulted in a high AUROCC of 0.63 (95% CI = 0.5-0.74%; p = 0.059), and analysis across only patients with diffuse large B-cell lymphoma (DLBCL) resulted in an AUROCC of 0.65 (95% CI = 0.51-0.79%; p = 0.046). With a cutoff point of 12, FENCE score can predict breakthrough infection events at 30.0% (95% CI = 17.8-47.4%). Conclusion: This study divided patients with lymphoma into risk groups according to FENCE score, showing that this instrument has discriminatory ability in predicting FN events, these being more likely to occur in patients in the intermediate- and high-risk groups. Multicenter studies are needed to validate this clinical risk score.

Deferiprone, an iron chelator, alleviates platelet hyperactivity in patients with ß-thalassaemia/HbE.

Background: Hyperfunctional platelets play important roles in thromboembolism in patients with ß-thalassaemia/ haemoglobin E (ß-thal/HbE). Our previous study revealed ex vivo inhibitory effects of deferiprone on normal platelets. Herein, we aimed to investigate the in vivo effects on platelets in patients with ß-thal/HbE. Methods: A prospective, self-controlled clinical study on 30 patients with ß-thal/HbE who had received therapeutic deferiprone (20.8-94.5 mg/kg/day) was conducted. The study included a 4-week washout period followed by 4 and 12 weeks of deferiprone treatment. Platelet aggregation was performed by a turbidimetric method. Levels of deferiprone and soluble platelet (sP)-selectin in serum were measured by high-performance liquid chromatography (HPLC) and enzyme-linked immunosorbent assay (ELISA) kit, respectively. Results: The washout period significantly enhanced platelet hyperactivity both in patients who had undergone splenectomy and in those who had not. At 2 hours following the administration of a single dose of deferiprone, platelet sensitivity to ADP and arachidonic acid was significantly reduced. The inhibitory effects of deferiprone were gradually increased over the period of 4 and 12 weeks. Deferiprone also depressed sP-selectin levels, but the effect was stable over longer follow-up periods. Correlation analysis demonstrated the relationship between serum levels of deferiprone, sP-selectin, and platelet activities induced by ADP and arachidonic acid. Conclusion: We first demonstrated the in vivo antiplatelet effect and benefit of short-term treatment of deferiprone in patients with ß-thal/HbE. The impact on thrombotic outcomes deserves further study.

Immunogenicity and risks associated with impaired immune responses following SARS-CoV-2 vaccination and booster in hematologic malignancy patients: an updated meta-analysis.

Patients with hematologic malignancies (HM) have demonstrated impaired immune responses following SARS-CoV-2 vaccination. Factors associated with poor immunogenicity remain largely undetermined. A literature search was conducted using PubMed, EMBASE, Cochrane, and medRxiv databases to identify studies that reported humoral or cellular immune responses (CIR) following complete SARS-CoV-2 vaccination. The primary aim was to estimate the seroconversion rate (SR) following complete SARS-CoV-2 vaccination across various subtypes of HM diseases and treatments. The secondary aims were to determine the rates of development of neutralizing antibodies (NAb) and CIR following complete vaccination and SR following booster doses. A total of 170 studies were included for qualitative and quantitative analysis of primary and secondary outcomes. A meta-analysis of 150 studies including 20,922 HM patients revealed a pooled SR following SARS-CoV-2 vaccination of 67.7% (95% confidence interval [CI], 64.8-70.4%; I2 = 94%). Meta-regression analysis showed that patients with lymphoid malignancies, but not myeloid malignancies, had lower seroconversion rates than those with solid cancers (R2 = 0.52, P < 0.0001). Patients receiving chimeric antigen receptor T-cells (CART), B-cell targeted therapies or JAK inhibitors were associated with poor seroconversion (R2 = 0.39, P < 0.0001). The pooled NAb and CIR rates were 52.8% (95% CI; 45.8-59.7%, I2 = 87%) and 66.6% (95% CI, 57.1-74.9%; I2 = 86%), respectively. Approximately 20.9% (95% CI, 11.4-35.1%, I2 = 90%) of HM patients failed to elicit humoral and cellular immunity. Among non-seroconverted patients after primary vaccination, only 40.5% (95% CI, 33.0-48.4%; I2 = 87%) mounted seroconversion after the booster. In conclusion, HM patients, especially those with lymphoid malignancies and/or receiving CART, B-cell targeted therapies, or JAK inhibitors, showed poor SR after SARS-CoV-2 vaccination. A minority of patients attained seroconversion after booster vaccination. Strategies to improve immune response in these severely immunosuppressed patients are needed.

Comparison of Molecular International Prognostic Scoring System (M-IPSS) and Revised International Prognostic Scoring System (R-IPSS) in Thai patients with myelodysplastic neoplasms.

INTRODUCTION: Risk stratification is essential for treatment decision in myelodysplastic neoplasms (MDS). Molecular international prognostic scoring system (M-IPSS) has been recently developed combining somatic mutations and clinical information being used in the revised international prognostic scoring system (R-IPSS). OBJECTIVE: We aimed to explore the performances of M-IPSS and R-IPSS in Thai patients with MDS. METHOD: MDS patients were stratified into risk categories using R-IPSS and M-IPSS scores. The performance of both models were evaluated for prognostic prediction. RESULTS: One hundred and sixty-two MDS patients were recruited from the multicenter study. Survival analysis revealed that both R-IPSS and M-IPSS were good prediction models with the Concordance Index (C-index) of 0.71 (95% Confidence interval [CI] 0.64-0.78) and 0.75 (95% CI 0.69-0.80), respectively (p = 0.22). Comparing the two, 13 of 162 (8%) cases were re-staged between lower and higher risks which would have affected treatment decisions. CONCLUSION: Our study showed that R-IPSS score can be used for risk stratification in most Thai patients. A prediction model using somatic mutations specifically in Asian patients should be formulated in the future.

Genetic mutations associated with blood count abnormalities in myeloid neoplasms.

INTRODUCTION: Myelodysplastic syndromes (MDS) predominantly present with varying degrees of cytopenia, while myelodysplastic syndromes/myeloproliferative neoplasms (MDS/MPN) exhibit proliferative features. Genetic defects underlying different complete blood count (CBC) alterations remain to be defined. OBJECTIVE: We aimed to evaluate mutations and impacts on abnormal blood counts in MDS and MDS/MPN. METHOD: MDS and MDS/MPN patients were recruited and sequenced by targeted next-generation sequencing. Clinical parameters, especially CBC, were evaluated for the association with genetic abnormalities and clinical outcomes. RESULTS: A total of 168 patients with myeloid neoplasms were recruited (92 cases of low-risk MDS, 57 cases of high-risk MDS and 19 cases of MDS/MPN). Compared to low-risk MDS and MDS/MPN, patients with high-risk MDS were presented with more severe neutropenia with 17.5% showing absolute neutrophil counts (ANC) lower than 0.5 × 109/L. Patients with MDS/MPN more commonly harboured mutations and had a higher number of mutations per case than low-risk MDS (94.7% vs. 56.5%; p < 0.001 and 3 vs. 1; p < 0.001, respectively). Patients with SF3B1 mutations showed lower haemoglobin levels than wild-type (7.9 vs. 8.4 g/dL, p = 0.02), but were associated with normal platelet counts (286 vs. 93 × 109/L; p < 0.001). Patients with U2AF1 mutations were associated with more severe leukopenia than wild-type (3 vs. 4.18 × 109/L; p = 0.02). KRAS mutations were associated with monocytosis (p < 0.001). Multivariate analysis revealed high-risk MDS, MDS/MPN, severe neutropenia (ANC < 0.5 × 109/L), and mutations in ASXL1 and SETBP1 were associated with inferior survival outcomes. CONCLUSION: Certain mutations were related to more severe anaemia, lower white blood cell count or monocytosis in Asian MDS and MDS/MPN patients.

Thrombosis with thrombocytopenia after the second ChAdOx1 nCoV-19 vaccination: A possible immunological mechanism independent of anti-platelet factor 4 antibody.

BACKGROUND: Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a distinctive syndrome characterized by unusual site thrombosis accompanied by thrombocytopenia following adenoviral vector vaccines against severe acute respiratory syndrome coronavirus 2. Platelet-activating anti-platelet factor 4-dependent antibodies (anti-PF4 Abs) have been identified as pathogenic antibodies in almost all patients. OBJECTIVE: We proposed an immunological mechanism of VITT independent of anti-PF4 Abs. METHODS: Case report. RESULTS: A 68-year-old Thai woman developed pulmonary embolism and deep vein thrombosis with thrombocytopenia one week after the second ChAdOx1 nCoV-19 vaccination with undetectable anti-PF4 Abs. The platelet count responded rapidly to intravenous immunoglobulin and steroids. Therefore, the high clinical suspicion is essential for early recognition and prompt management irrespective of anti-PF4 Ab results. CONCLUSIONS: We hypothesize that platelet and endothelial activation following ChAdOx1 nCoV-19 vaccination may lead to generation of pathogenic antibodies which account for VITT independent of anti-PF4 Abs.

Expression of Programmed Cell Death-1 and Programmed Cell Death Ligands in Nodal Peripheral T-Cell Lymphoma: Expression Pattern and Potential Prognostic Relevance.

Programmed cell death (PD)/PD-ligands (PD-Ls) pathway plays an important role in the regulation of physiologic immune response. Several cancers, including lymphoma exhibit abnormal PD-1/PD-Ls expression, which may contribute to treatment failure, progression, and inferior outcomes. PD-1/PD-Ls expression has predominantly been described in B-cell lymphoma; such data in peripheral T-cell lymphoma (PTCL) is limited. We described PD-1/PD-Ls expression patterns and associations with clinical characteristics and outcomes, in patients with systemic PTCLs. Correlation between PD-1/PD-Ls expression and outcomes was analyzed in patients who received lymphoma-specific therapy. PD-1/PD-Ls expression was observed across all common PTCL histologies at different proportions (PD-1 0%-76.9%, PD-L1 38.5%-62.5%, and PD-L2 62.5%-100%) with PD-1 being highly expressed in angioimmunoblastic T-cell lymphoma. Baseline characteristics were comparable between PD-1/PD-Ls expression status. Of 47 patients who received lymphoma-specific therapy, outcomes were similar across all PD-L1/PD-L2 subgroups. In the Cox proportional hazard analysis, treatment response was the only factor associated with survival outcomes. However, PD-1/PD-Ls expression, either in lymphoma or stroma, was not a predictor for survival outcomes. In conclusion, differential PD-1/PD-Ls expressions were observed among various histological PTCL subtypes. In this study, we were unable to demonstrate an association between PD-1/PD-Ls expression, clinical characteristics, treatment response, and outcomes of PTCL patients.

Post-treatment anti-Mullerian hormone (AMH) levels predict long-term ovarian dysfunction in women with hematological malignancies.

Fertility is a concern in young female survivors of hematological malignancies. We evaluated post-treatment ovarian function in patients by measuring anti-Müllerian hormone (AMH) and conventional hormone levels to correlate with menstruation and fertility.The prospective cohort study included 29 reproductive-aged women diagnosed with Hodgkin lymphoma (n = 11), non-Hodgkin lymphoma (n = 9) or acute myeloid leukemia (n = 9). Hormone assays were measured after treatment was completed and compared to age-matched healthy controls. Menstrual changes and postmenopausal symptoms were assessed annually.Serum AMH levels were significantly lower compared to controls at 12 months after treatment [1.0 (0.18-1.8) vs. 2.2 (1.8-4.8) ng/mL; P < .001). At 12 months, FSH and LH levels were significantly higher compared to controls. The interruption of menstrual cycles was observed in 80% (22/27) of patients. Normal menstruation returned at a median of 1.5 months after cessation of treatment in 71% of patients, while 29% of patients had persistent amenorrhea. Low AMH levels at 12 months after therapy (<1 ng/mL) correlated more strongly with abnormal menstrual cycles than normal AMH levels (46% vs. 0%, P = .04). Four patients with low AMH consulted an infertility clinic.In summary, low serum AMH at 12 months after chemotherapy was associated with persistent menstrual abnormalities.

Mutated JAK2 signal transduction in human induced pluripotent stem cell (iPSC)-derived megakaryocytes.

Janus kinase 2 (JAK2) gene mutations are the main drivers for polycythemia vera (PV) and essential thrombocythemia (ET). The mechanisms of single altered gene causing two different diseases are unclear. Additionally, novel treatments specifically targeting mutated JAK2 proteins are needed. In this study, the induced pluripotent stem cells (iPSCs) were virally transduced to express wild-type JAK2 (JAK2WT), JAK2p.V617F (JAK2V617F) or JAK2p.N542_E543del (JAK2exon12) under a doxycycline-inducible system. The modified iPSCs which were differentiated into megakaryocytes in the presence vs. absence of doxycycline were compared to ensure that the differences were solely from mutated JAK2 expressions. The JAK2V617-expressing iPSCs yielded significantly higher numbers of megakaryocytes consistent with the ET phenotype, while there was no enhancement by JAK2exon12 expression compatible with the pure erythrocytosis in humans. Capillary Western analyses revealed significantly greater JAK2 phosphorylation in iPSCs carrying JAK2V617F but not in JAK2WT and JAK2exon12 iPSCs. Activation of STAT3, STAT5 and AKT was increased by JAK2V617F, while they were decreased in JAK2exon12 iPSCs. Notably, interferon alpha and/or arsenic trioxide inhibited megakaryocytes proliferation and reduced JAK2, STAT3, STAT5 and AKT phosphorylation in mutant JAK2-expressing iPSCs compared with those without induction. In conclusion, JAK2V617F expression in iPSCs preferentially promoted megakaryocytes with a signaling profile distinctive from JAK2exon12 expression. Treatments with interferon alpha or arsenic trioxide preferentially suppressed the mutated over wild-type JAK2 signaling. This iPSC model is helpful in mechanistic studies and novel therapy screen for myeloproliferative neoplasm.

Excellent Prognosis of Low-Risk Myelodysplastic Syndromes (MDS) Without Detectable Myeloid-Related Mutations.

BACKGROUND: Unexplained cytopenia (UC) and low-risk myelodysplastic syndrome (MDS) are distinguished mainly by morphologic dysplasia, which sometimes shows inter-observer discrepancy. We hypothesized that gene mutations are strong prognostic factors for these low-risk patients. MATERIALS AND METHODS: We enrolled patients from 4 medical centers with unexplained cytopenia of at least 1 lineage. Diagnosis of low-risk MDS was made according to WHO 2016 classification and a revised international prognostic scoring system (R-IPSS) score of ≤ 3.5. DNA was extracted from bone marrow or blood and sequenced by targeted next generation sequencing (NGS). RESULTS: One hundred twenty-one patients were recruited: 25% with UC and 75% with low-risk MDS. Complete blood counts were similar, but low-risk MDS patients carried higher numbers of mutations (1 vs. 0; P = .04) than UC patients. Overall, the most frequent mutated genes were TET2 (14.6%), SF3B1 (12.2%), and ASXL1 (9.7%). Survival rates of low-risk MDS patients versus UC patients were not significantly different. UC patients and low-risk MDS patients without genetic abnormalities showed superior 5-year progression free survival compared to MDS patients with mutations (100% vs. 76.0%; P = .005). Overall, ASXL1 mutations were associated with decreased 4-year overall survival compared to wild-type (59% vs. 31%; P = .01). In a multivariate analysis, ASXL1 and DNMT3A mutations in low-risk MDS patients were associated with a higher risk of disease progression with hazard ratios of 7.88 (95% CI 1.76-35.32, P = .01) and 7.45 (95% CI 1.61-34.46, P = .01), respectively. CONCLUSION: Mutation detection is important for proper risk stratification of patients presenting with idiopathic cytopenia.

Particulate Matter 2.5 and Hematological Disorders From Dust to Diseases: A Systematic Review of Available Evidence.

Particulate matter 2.5 (PM2.5) in the air enters the human body by diffusion into the blood. Therefore, hematological abnormalities might occur because of these toxic particles, but few studies on this issue have been reported. According to Cochrane guidance, we performed a systematic review on the relationship between exposure to PM2.5 and the risk of hematological disorders. Ten articles were included in this review. Anemia was found among children and elderly populations with 2- to 5-year PM2.5 exposure. Young children from mothers exposed to air pollution during pregnancy had a higher incidence of leukemia similar to the elderly. Supporting these data, outdoor workers also showed abnormal epigenetic modifications after exposure to very high PM2.5 levels. Adults living in high PM2.5 areas for 2 years were more likely to develop thrombocytosis. Finally, elderly populations with 7- to 8-year PM2.5 exposure showed increased risks of venous thromboembolism. In conclusion, the associations between PM2.5 and hematological aberrations among high-risk people with long-term exposure were reported.

High B-cell activating factor levels in multi-transfused thalassemia patients.

OBJECTIVES: To assess the associations between B-cell activating factor (BAFF) and alloimmunisation in multi-transfused thalassemia. BACKGROUND: Red blood cell (RBC) alloimmunisation is a complication of multi-transfused thalassemia. BAFF is promoting B cells that produce alloantibodies. METHODS/MATERIALS: Multi-transfused thalassemia, 15 years or older, were recruited in the cohort study. Alloantibodies and BAFF levels were analysed. RESULTS: Of 114 patients, the overall prevalence of RBC alloimmunisation was 29.8%. The most common alloantibodies were anti-E, anti-Mia and anti-c. BAFF levels were different among the three groups; the patients with baseline alloantibodies (median ± interquartile range 1251 ± 474 pg/ml), without alloantibodies (1098 ± 453) and healthy controls (719 ± 306), p < 0.001. The BAFF level was elevated in the >25 years old patients (vs. the <25, p = 0.011) and the buffy-coat-reduced blood recipients (vs. the pre-storage leukocyte-depletion, p = 0.005). Absolute lymphocyte count was higher in the patients without baseline alloantibodies (vs. with baseline alloantibodies, p = 0.049) and the splenectomised patients (vs. the non-splenectomised patients, p < 0.001). Of the 72 patients without baseline antibodies, four who developed new antibodies showed no statistically different BAFF levels compared with those without new antibodies after 40-month follow-up (1296 ± 734 vs. 1062 ± 460, p = 0.491). In multivariate analysis, BAFF to absolute lymphocyte ratio was independently associated with RBC alloimmunisation (odds ratio 3.07, 95% confidence interval 1.124-8.369, p = 0.029). CONCLUSION: B-cell activating factor (BAFF) levels were elevated in multi-transfused thalassemia and the BAFF to absolute lymphocyte ratio was associated with red blood cell (RBC) alloimmunisation.

Inhibitory Mechanisms of Lusianthridin on Human Platelet Aggregation.

Lusianthridin is a phenanthrene derivative isolated from Dendrobium venustum. Some phenanthrene compounds have antiplatelet aggregation activities via undefined pathways. This study aims to determine the inhibitory effects and potential mechanisms of lusianthridin on platelet aggregation. The results indicated that lusianthridin inhibited arachidonic acid, collagen, and adenosine diphosphate (ADP)-stimulated platelet aggregation (IC50 of 0.02 ± 0.001 mM, 0.14 ± 0.018 mM, and 0.22 ± 0.046 mM, respectively). Lusianthridin also increased the delaying time of arachidonic acid-stimulated and the lag time of collagen-stimulated and showed a more selective effect on the secondary wave of ADP-stimulated aggregations. Molecular docking studies revealed that lusianthridin bound to the entrance site of the cyclooxygenase-1 (COX-1) enzyme and probably the active region of the cyclooxygenase-2 (COX-2) enzyme. In addition, lusianthridin showed inhibitory effects on both COX-1 and COX-2 enzymatic activities (IC50 value of 10.81 ± 1.12 µM and 0.17 ± 1.62 µM, respectively). Furthermore, lusianthridin significantly inhibited ADP-induced suppression of cAMP formation in platelets at 0.4 mM concentration (p < 0.05). These findings suggested that possible mechanisms of lusianthridin on the antiplatelet effects might act via arachidonic acid-thromboxane and adenylate cyclase pathways.