Microvesicles of osteoblasts modulate bone marrow mesenchymal stem cell-induced apoptosis to curcumin in myeloid leukemia cells

Microvesicles (MVs) derived from bone marrow niche components have an important role in genetic reprogramming and subsequent drugs induce apoptosis in leukemic cells. Here, we have found that undertreatment of curcumin or daunorubicin, the cross-talk through MVs of KG-1-bone marrow mesenchymal stem cells (BMSCs), significantly downregulates the expression of the survival gene osteopontin (OPN), CXCL-12, IL-6 (interleukin-6), STAT-3, and VCAM-1 (vascular cell adhesion molecule 1) in treated-KG-1 cells as well as exclusively upregulates CXCL-12 in BMSCs. Drug treated-cell populations’ MVs of both single cultured osteoblasts (OBs) and cocultured KG-1 + BMSCs + OBs similarly upregulate survival mediators’ OPN, CXCL-12, IL-6, STAT-3, and VCAM-1 in treated-KG-1 cells. Likewise, isolated MVs from KG-1 cells or communication between KG-1, BMSCs, and OBs treated by drugs increase the expression of genes OPN, CXCL-12, IL-6, STAT3, and VCAM-1 by OBs. MVs derived from KG-1 + BMSCs + OBs reduce drug-induced apoptosis in KG-1 cells. This suggests MVs-mediated information transfer is a procedure whereby OBs could overcome BMSCs-induced apoptosis in drug-treated-KG-1 cells.     

A new analytical formula for neutron capture gamma dose calculations in double-bend mazes in radiation therapy

BackgroundPhotoneutrons are produced in radiation therapy with high energy photons. Also, capture gamma rays are the byproduct of neutrons interactions with wall material of radiotherapy rooms.AimIn the current study an analytical formula was proposed for capture gamma dose calculations in double bend mazes in radiation therapy rooms.Materials and methodsA total of 40 different layouts with double-bend mazes and a 18 MeV photon beam of Varian 2100 Clinac were simulated using MCNPX Monte Carlo (MC) code. Neutron capture gamma ray dose equivalent was calculated by the MC method along the maze and at the maze entrance door of all the simulated rooms. Then, all MC resulted data were fitted to an empirical formula for capture gamma dose calculations. Wu–McGinley analytical formula for capture gamma dose equivalent at the maze entrance door in single-bend mazes was also used for comparison purposes.ResultsFor capture gamma dose equivalents at the maze entrance door, the difference of 2–11% was seen between MC and the derived equation, while the difference of 36–87% was found between MC and the Wu–McGinley methods.ConclusionOur results showed that the derived formula results were consistent with the MC results for all of 40 different geometries. However, as a new formula, further evaluations are required to validate its use in practical situations. Finally, its application is recommend for capture gamma dose calculations in double-bend mazes to improve shielding calculations.     

Effect of carboxymethylation conditions on the water-binding capacity of chitosan-based superabsorbents

A superabsorbent polymer (SAP) from chitosan was provided via carboxymethylation of chitosan, followed by cross-linking with glutaraldehyde and freeze-drying. This work was focused on an investigation of the effects of monochloroacetic acid (MCAA), sodium hydroxide, and reaction time on preparation of carboxymethyl chitosan (CMCS). The CMCS products were characterized using FTIR spectroscopy, and their degrees of substitution (DS) were measured using conductimetry and FTIR analysis. The highest DS value was obtained when the carboxymethylation reaction was carried out using 1.75 g MCAA and 1.75 g NaOH per g of chitosan in 4 h. The water solubilities of the CMCS products at various pHs were also evaluated, and the results indicated a significant impact of the reaction parameters on the solubility of CMCS. The CMCSs with the highest DS value resulted in SAPs having the highest water-binding capacity (WBC). The WBC of the best SAP measured after 10 min exposure in distilled water, 0.9% NaCl solution, synthetic urine, and artificial blood was 104, 33, 30, and 57 g/g, respectively. The WBC of this SAP at pH 2-9 passed a maximum at pH 6.     

Conditions to improve expansion of human mesenchymal stem cells based on rat samples

AIM: To improve the isolation and expansion of human marrow-derived mesenchymal stem cells (MSCs) based on rat samples. METHODS: Based on the fact that rat MSCs are relatively easy to obtain from a small aspirate, bone marrow-derived MSCs from rat were cultured and characterized to set up the different protocols used in this study. Then, accordingly, almost the same protocols were performed on human healthy bone marrow samples, after obtaining approval of the ethics committee and gaining informed consent. We used different protocols and culture conditions, including the type of basal media and the culture composition. The MSCs were characterized by immunophenotyping and differentiation. RESULTS: There was no difference in morphology and proliferation capacity between different culture media at the first passage. During the 5-7th passages, the cells gradually lost their morphology and proliferation potential on Dulbecco’s modified Eagle’s medium (DMEM) high glucose and α modified Eagle’s medium. Although the cells expanded rapidly for up to 10 passages on DMEM low glucose containing 10% to 15% fetal calf serum (FCS), their proliferation was arrested without change in morphology and differentiation capacity at the third passage on 5% FCS. Flow cytometric analysis and functional tests confirmed that more than 90% of marrow cells which were isolated and expanded by our selective protocols were MSCs. CONCLUSION: We improved the isolation and expansion of human bone marrow derived MSCs, based on rat sample experiments, for further experimental and clinical use.     

Neurofeedback Training for Opiate Addiction: Improvement of Mental Health and Craving

Psychological improvements in patients with substance use disorders have been reported after neurofeedback treatment. However, neurofeedback has not been commonly accepted as a treatment for substance dependence. This study was carried out to examine the effectiveness of this therapeutic method for opiate dependence disorder. The specific aim was to investigate whether treatment leads to any changes in mental health and substance craving. In this experimental study with a pre-post test design, 20 opiate dependent patients undergoing Methadone or Buprenorphine maintenance treatment were examined and matched and randomized into two groups. While both experimental and control groups received their usual maintenance treatment, the experimental group received 30 sessions of neurofeedback treatment in addition. The neurofeedback treatment consisted of sensory motor rhythm training on Cz, followed by an alpha-theta protocol on Pz. Data from the general health questionnaire and a heroin craving questionnaire were collected before and after treatment. Multivariate analysis of covariance showed that the experimental group achieved improvement in somatic symptoms, depression, and total score in general mental health; and in anticipation of positive outcome, desire to use opioid, and relief from withdrawal of craving in comparison with the control group. The study supports the effectiveness of neurofeedback training as a therapeutic method in opiate dependence disorder, in supplement to pharmacotherapy.