Iron overload as a risk factor for poor graft function following allogeneic hematopoietic stem cell transplantation.

Hematological malignancies are increasingly treated with allogeneic hematopoietic stem cell transplantation (allo-HSCT). Unfortunately, iron overload is a frequent adverse effect of allo-HSCT and is associated with poor prognosis. In the present study, we investigated hematopoiesis in iron-overloaded mice and elucidated the effects of iron overload on the bone marrow (BM) microenvironment. Iron-overloaded BALB/C mice were generated by injecting 20 mg/mL saccharated iron oxide intraperitoneally. Hematoxylin-eosin staining was performed to evaluate the effects of an iron overload in mice. BM cells obtained from C57BL/6 mice were transplanted into irradiated BALB/C mice (whole-body irradiation of 4 Gy, twice with a 4-hours interval) by tail vein injection. Two weeks after allo-HSCT, the hematopoietic reconstitution capacity was evaluated in recipients by colony-forming assays. Histopathological examinations showed brown-stained granular deposits, irregularly arranged lymphocytes in the liver tissues, and blue-stained blocks in the BM collected from mice received injections of high-dose saccharated iron oxide (20 mg/mL). Iron-overloaded mice showed more platelets, higher-hemoglobin (HGB) concentration, fewer granulocyte-macrophage colony-forming units (CFU-GM), erythrocyte colony-forming units (CFU-E), and mixed granulocyte/erythrocyte/monocyte/megakaryocyte colony-forming units (CFU-mix) than healthy mice. Iron-overloaded recipients presented with reduced erythrocytes and HGB concentration in peripheral blood, along with decreased marrow stroma cells, CFU-GM, CFU-E, and CFU-mix relative to healthy recipients. Taken together, our findings demonstrate that iron overload might alter the number of red blood cells after transplantation in mice by destroying the BM microenvironment, thereby affecting the recovery of BM hematopoietic function.

Severe renal impairment as an adverse prognostic factor for survival in newly diagnosed multiple myeloma patients.

BACKGROUND: Renal impairment (RI) is associated with poor survival in newly diagnosed multiple myeloma (MM) patients. Renal function recovery has been one of the main therapeutic goals in those patients. METHODS: The records from 393 newly diagnosed MM patients in our hospital between January 2012 and December 2016 were retrospectively analyzed. RI was defined as an eGFR < 40 mL/min according to the novel IMWG criteria. RI patients were categorized based on their renal function at diagnosis: severe RI: eGFR < 30 mL/min, and mild RI: 30 mL/min ≤ eGFR <40 mL/min. We explored whether RI, and particularly severe RI, was an adverse prognostic factor for survival, and investigated the impact of renal function recovery on survival. RESULTS: Severe RI, hemoglobin <100 g/L, LDH ≥ 245 U/L, hyperuricemia, 1q21 amplification, and lack of novel agent treatment were associated with decreased overall survival (OS). Severe RI patients with renal response had a median OS of 27 months compared with 18 months for those patients without renal response (P = .030), but their median OS was still significantly lower than that for patients without severe RI, which was 51 months. In severe RI patients, the overall renal response rate in bortezomib-based regimens was significantly higher than that in nonbortezomib-based regimens. CONCLUSION: Our results suggest that severe RI is an adverse prognostic factor for survival in newly diagnosed MM patients, restoration of renal function may improve survival, and bortezomib-based regimens may be the preferred treatment in patients with severe RI.

Bone marrow mesenchymal stem cells alleviate the daunorubicin-induced subacute myocardial injury in rats through inhibiting infiltration of T lymphocytes and antigen-presenting cells.

INTRODUCTION: Bone marrow mesenchymal stem cells (BMSCs) have been extensively investigated from a perspective on cardiac regeneration therapy. The current study aimed to investigate the protective effect conferred by BMSCs in subacute myocardial injury, and to identify an appropriate BMSC reinfusion time. METHODS: BMSCs were isolated from human bone marrow blood. Daunorubicin (DNR)-induced subacute myocardial models were subsequently established. The rats with DNR-induced subacute myocardial injury were injected with dexrazoxane (DZR) and/or BMSCs at varying time points, after which cardiac function was evaluated by assessing left ventricular ejection fraction (LVEF) and fraction shortening (FS). The myocardial structural changes were analyzed, after which the levels of CD3 and human leukocyte antigen DR (HLA-DR) were examined to further validate the mechanism by which BMSCs could influence subacute myocardial injury. RESULTS: BMSCs combined with DZR treatment enhanced the cardiac function of rats with DNR-induced myocardial injury, as reflected by increased LVEF and FS. DNR-induced myocardial injuries were mitigated via the application of BMSCs combined with treatment of DZR, accompanied by diminished infiltration or vacuolization. Moreover, BMSCs were observed to alleviate infiltration of T lymphocyte and antigen-presenting cells, as evidenced by reduced expression of CD3 and HLA-DR. CONCLUSION: Taken together, this study demonstrates that BMSCs could protect against DNR-induced myocardial injury, especially in the first three days of DNR administration. BMSCs combined with DZR exert a better therapeutic effect, but there are individual differences.

Distribution and drug resistance of pathogens of blood stream infection in patients with hematological malignancies after chemotherapy / 中华血液学杂志

Objective@#To investigate the distribution and resistance of pathogens isolated from blood cultures in patients with hematological malignancies after chemotherapy in Union Hospital of Fujian Medical University so as to understand the real situation of blood stream infection (BSI) and provide the basis for rational use of antibiotics in clinic.@*Methods@#The data of 657 strains isolated from blood culture specimens of patients with hematological malignancies from January 2013 to December 2016 were collected analyzed.@*Results@#A total of 657 cases of blood culture positive bacterial strains were included in the study, involving 410 cases (62.4%) with single Gram-negative bacteria (G- bacteria) , 163 cases (24.8%) with single Gram-positive bacteria (G+ bacteria) , 50 cases (7.6%) with single fungi. The most common 5 isolates in blood culture were Klebsiella pneumoniae (17.5%) , Escherichia coli (17.2%) , Coagulase negative staphylococci (CNS) (14.9%) , Pseudomonas aeruginosa (14.2%) and Staphylococcus aureus (3.5%) . The extended-spectrum beta-lactamase (ESBL) production rates of Klebsiella pneumoniae and Escherichia coli were 25.2% and 55.8%, respectively. ESBL producing strains were almost more resistant than non-ESBL producing strains. The resistance rates of Enterobacteriaceae to carbapenems, piperacillin/tazobactam and tigecycline were lower than 14.0%. The resistance rates of Pseudomonas aeruginosa to a variety of drugs were lower than 12.0%. Tigecycline-resistant Acinetobacter baumannii bacteria were not detected, and the resistance rates of Acinetobacter baumannii to cefixime and cefotaxime were 7.1%. Methicillin-resistant strains in CNS (MRCNS) and in Staphylococcus aureus (MRSA) accounted for 84.7% and 43.5%, respectively. Vancomycin, linezolid and tigecycline-resistant G+ bacteria were not detected.@*Conclusion@#The pathogens isolated from blood culture were widely distributed. Most of them were G- bacteria, and the resistance to antibiotics was quite common. Furhermore, vancomycin, linezolid and tigecycline can be chosen empirically to treat patiens who ar suspected to have G+ bacterial BSI.