Reversal of MYB-dependent suppression of MAFB expression overrides leukaemia phenotype in MLL-rearranged AML.

The transcription factor MYB plays a pivotal role in haematopoietic homoeostasis and its aberrant expression is involved in the genesis and maintenance of acute myeloid leukaemia (AML). We have previously demonstrated that not all AML subtypes display the same dependency on MYB expression and that such variability is dictated by the nature of the driver mutation. However, whether this difference in MYB dependency is a general trend in AML remains to be further elucidated. Here, we investigate the role of MYB in human leukaemia by performing siRNA-mediated knock-down in cell line models of AML with different driver lesions. We show that the characteristic reduction in proliferation and the concomitant induction of myeloid differentiation that is observed in MLL-rearranged and t(8;21) leukaemias upon MYB suppression is not seen in AML cells with a complex karyotype. Transcriptome analyses revealed that MYB ablation produces consensual increase of MAFB expression in MYB-dependent cells and, interestingly, the ectopic expression of MAFB could phenocopy the effect of MYB suppression. Accordingly, in silico stratification analyses of molecular data from AML patients revealed a reciprocal relationship between MYB and MAFB expression, highlighting a novel biological interconnection between these two factors in AML and supporting new rationales of MAFB targeting in MLL-rearranged leukaemias.

The efficacy and safety of triplet regimens based on pomalidomide and dexamethasone for treatment of relapsed/refractory multiple myeloma: a systematic review and meta-analysis.

OBJECTIVE: Triplet regimens based on pomalidomide and dexamethasone have been applied to treat relapsed/refractory multiple myeloma, but the safety and efficacy are not yet very clear. This meta-analysis aimed at comparing the safety and efficacy of different triplet therapies and analyzing the best therapy regimen. MATERIALS AND METHODS: A comprehensive literature search identified a total of 615 studies, and 22 studies assessing 1,889 subjects met the inclusion criteria of this meta: phase II/III trial, over 2 median lines of prior therapy, and detailed efficacy outcomes like overall response rate (ORR), overall survival, and progression-free survival (PFS). All statistical analyses were performed by Revman version 5.3, and the heterogeneity was tested by I2 (25% indicating low heterogeneity, 50% moderate, and 75% high). For those with less heterogeneity, fixed-effect model was used. With a significant high heterogeneity, a random-effect model was used. RESULTS: Pooled analysis showed ORR 66.2% across all triplet regimens based on pomalidomide and dexamethasone. Among all triplet regimens, therapy containing bortezomib showed the highest ORR (90.3%), and the one containing elotuzumab showed the lowest ORR (41.2%). The pooled ORRs for the remaining treatment regimens are as follows: cyclophosphamide (70.1%), isatuximab (66.3%), daratumumab (61.2%), clarithromycin (60.0%), pembrolizumab (47.3%). A total of 21 adverse events appeared in the included studies, with neutropenia being the highest incidence of hematologic adverse events (32.1%) and cough being the highest incidence of non-hematologic adverse events (43.3.%). CONCLUSIONS: Three-drug regimens based on pomalidomide and dexamethasone could yield excellent overall response rate to relapsed/refractory multiple myeloma, but there are still various adverse events; therefore, consequent studies should address these adverse events.

Performance of the new biological small- and wide-angle X-ray scattering beamline 13A at the Taiwan Photon Source.

Recent developments in the instrumentation and data analysis of synchrotron small-angle X-ray scattering (SAXS) on biomolecules in solution have made biological SAXS (BioSAXS) a mature and popular tool in structural biology. This article reports on an advanced endstation developed at beamline 13A of the 3.0 GeV Taiwan Photon Source for biological small- and wide-angle X-ray scattering (SAXS-WAXS or SWAXS). The endstation features an in-vacuum SWAXS detection system comprising two mobile area detectors (Eiger X 9M/1M) and an online size-exclusion chromatography system incorporating several optical probes including a UV-Vis absorption spectrometer and refractometer. The instrumentation and automation allow simultaneous SAXS-WAXS data collection and data reduction for high-throughput biomolecular conformation and composition determinations. The performance of the endstation is illustrated with the SWAXS data collected for several model proteins in solution, covering a scattering vector magnitude q across three orders of magnitude. The crystal-model fittings to the data in the q range ∼0.005-2.0 Å-1 indicate high similarity of the solution structures of the proteins to their crystalline forms, except for some subtle hydration-dependent local details. These results open up new horizons of SWAXS in studying correlated local and global structures of biomolecules in solution.

Optical design and performance of the biological small-angle X-ray scattering beamline at the Taiwan Photon Source.

The optical design and performance of the recently opened 13A biological small-angle X-ray scattering (SAXS) beamline at the 3.0 GeV Taiwan Photon Source of the National Synchrotron Radiation Research Center are reported. The beamline is designed for studies of biological structures and kinetics in a wide range of length and time scales, from angstrom to micrometre and from microsecond to minutes. A 4 m IU24 undulator of the beamline provides high-flux X-rays in the energy range 4.0-23.0 keV. MoB4C double-multilayer and Si(111) double-crystal monochromators (DMM/DCM) are combined on the same rotating platform for a smooth rotation transition from a high-flux beam of ∼4 × 1014 photons s-1 to a high-energy-resolution beam of ΔE/E ≃ 1.5 × 10-4; both modes share a constant beam exit. With a set of Kirkpatrick-Baez (KB) mirrors, the X-ray beam is focused to the farthest SAXS detector position, 52 m from the source. A downstream four-bounce crystal collimator, comprising two sets of Si(311) double crystals arranged in a dispersive configuration, optionally collimate the DCM (vertically diffracted) beam in the horizontal direction for ultra-SAXS with a minimum scattering vector q down to 0.0004 Å-1, which allows resolving ordered d-spacing up to 1 µm. A microbeam, of 10-50 µm beam size, is tailored by a combined set of high-heat-load slits followed by micrometre-precision slits situated at the front-end 15.5 m position. The second set of KB mirrors then focus the beam to the 40 m sample position, with a demagnification ratio of ∼1.5. A detecting system comprising two in-vacuum X-ray pixel detectors is installed to perform synchronized small- and wide-angle X-ray scattering data collections. The observed beamline performance proves the feasibility of having compound features of high flux, microbeam and ultra-SAXS in one beamline.

Enhanced anticancer activity and endocytic mechanisms by polymeric nanocarriers of n-butylidenephthalide in leukemia cells.

PURPOSE: The purpose of this study was to investigate the antitumor mechanisms of n-butylidenephthalide (BP) and to further examine the delivery efficacy of polycationic liposome containing PEI and polyethylene glycol complex (LPPC)-encapsulated BP in leukemia cells. METHODS: MTS, flow cytometric and TUNEL assays were performed to assess cell viability and apoptosis. BP and BP/LPPC complex delivery efficiency was analyzed by full-wavelength fluorescent scanner and fluorescence microscope. The expressions of cell cycle- and apoptosis-related proteins were conducted by Western blotting. RESULTS: The results showed that BP inhibited leukemia cell growth by inducing cell cycle arrest and cell apoptosis. LPPC-encapsulated BP rapidly induced endocytic pathway activation, resulting in the internalization of BP into leukemia cells, causing cell apoptosis within 1 h. CONCLUSIONS: LPPC encapsulation enhanced the cytotoxic activity of BP and did not influence the effects of BP induction that suggested LPPC-encapsulated BP might be developed as anti-leukemia drugs in future.

[Analysis of pathogen spectrum and antimicrobial resistance of pathogens associated with hospital-acquired infections collected from 11 teaching hospitals in 2018].

Objective: To investigate the spectrum and antimicrobial resistance of major pathogens causing nosocomial infections in China, 2018. Methods: Non-duplicated nosocomial cases as well as pathogens causing bloodstream infections (BSI), hospital-acquired pneumonia (HAP) and intra-abdominal infections (IAI) from 11 teaching hospitals across China were collected. The minimum inhibitory concentrations (MICs) of clinically significant strains were determined by agar dilution method or broth microdilution method. The Clinical and Laboratory Standards Institute (CLSI) M100-S29 criteria were used for interpretation, and the WHONET-5.6 software was used in data analysis. Results: A total of 1 590 cases were collected, including 831 cases from BSI, 450 cases from HAP and 309 cases from IAI. The most prevalent pathogens causing BSI were Escherichia coli (29.2%, 243/831), Klebsiella pneumoniae (16.2%, 135/831) and Staphylococcus aureus (10.1%, 84/831); the most prevalent pathogens causing IAI were E. coli (26.2%, 81/309), Enterococcus faecium (15.5%, 48/309) and K. pneumoniae (13.3%, 41/309); while Acinetobacter baumanii (24.7%, 111/450), Pseudomonas aeruginosa (20.7%, 93/450) and K. pneumoniae (16.2%, 73/450) were dominated in HAP. All S. aureus were susceptible to tigecycline, linezolid, daptomycin and glycopeptides; 77.8% (105/135) of S. aureus strains were susceptible to ceftaroline. Methicillin-resistant S. aureus (MRSA) accounted for 29.6% (40/135) of all the S. aureus, and was lower than the accounted rate of methicillin-resistant coagulase-negative Staphylococcus (MRCNS) (83.7%, 41/49). One E. faecium strain (1.1%, 1/95) resistant to vacomycin and teicoplanin and one E. faecalis strain (2.3%, 1/43) resistant to linezolid was found. The prevalence of extended-spectrum ß-lactamase (ESBL) was 56.1% (193/344) in E. coli and 22.1% (55/249) in K. pneumonia; the rate of carbapenem resistant E. coli and K. pneumonia was 4.1% (14/344) and 22.9% (57/249), respectively; the percentage of ceftazidime/avibactam resistant E. coli and K. pneumonia was 2.3% (8/344) and 2.0% (5/249), respectively; the percentage of colistin resistant E. coli and K. pneumonia was 1.5% (5/344) and 7.6% (19/249), respectively; no E. coli and K. pneumonia strains were found resistant to tigecycline. The rate of carbapenem resistant A. baumanii and P. aeruginosa were 78.9% (146/185) and 36.7% (66/180), respectively. A. baumanii showed low susceptibility to the antimicrobial agents except colistin (99.5%, 184/185) and tigecycline (91.4%, 169/185). Colistin, amikacin and ceftazidime/avibactam demonstrated high antibacterial activity against P. aeruginosa with susceptility rate of 100% (180/180), 93.3% (168/180) and 85.6% (154/180), respectively. Conclusions: Nosocomial Gram-negative pathogens show high susceptibilities to tigecycline, colistin and ceftazidime/avibactam in vitro. Antimicrobial resistance in A. baumannii is a serious problem. The prevalence of carbapenem-resistant Enterobacteriaceae has increased, which should be monitored continuously in China.

Pithecellobium clypearia extract enriched in gallic acid and luteolin has antibacterial activity against MRSA and reduces resistance to erythromycin, ceftriaxone sodium and levofloxacin.

AIMS: Antibiotic adjuvants can give a second life to the antibiotics to which bacteria are highly resistant. We evaluated the antimicrobial effects of extracts from Pithecellobium clypearia against methicillin-resistant Staphylococcus aureus (MRSA) and also the potential for synergy with several antibiotics. METHODS AND RESULTS: For this study, four extracts from P. clypearia were tested on MRSA using the broth microdilution method for activity assessment. The ethyl acetate fraction (S20b) had the strongest antibacterial activity against MRSA among the fractions tested. In all, 14 compounds such as gallic acid and luteolin in S20b were analysed by UFLC-Q-TOF-MS/MS. S20b combined with erythromycin showed synergy effects against MRSA and combined with ceftriaxone sodium and levofloxacin showed additive effects against MRSA. Electron microscopy showed that extract S20b damaged the MRSA cell wall and K+ efflux measurements indicated that extract S20b increased cell membrane permeability. Moreover, S20b suppression of PBP2a expression was assessed by Western blot. Furthermore, an in vivo study was used to investigate the therapeutic potential of S20b based on a mouse pneumonia model. CONCLUSIONS: The in vitro study results have shown that S20b not only inhibits MRSA growth directly but also reduces the resistance of MRSA to the evaluated antibacterial agents. Based on the in vivo study, it can be concluded that S20b can treat pneumonia in the mouse model. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first research to demonstrate that S20b can inhibit MRSA growth and reduce drug resistance of clinical isolates to antibiotics. S20b has the potential to be used as a therapeutic agent against MRSA and treatment for MRSA pneumonia.

Analysis of Damage and Wound Healing in the Retinal Pigmented Epithelium.

Previous studies of retinal pigment epithelium (RPE) morphology found cell-level and spatial patterning differences in many quantitative metrics in comparing normal and disease conditions. However, most of these studies examined eyes from deceased animals. Here we sought to compare noninvasively imaged RPE cells from live mice to histopathology. We describe changes to improve noninvasive imaging of RPE in the live mouse. In retinal diseases, there can be invasion by Iba1-positive cells, which can be detected by noninvasive imaging techniques. Here we can detect potential Iba1-positive cells at the level of the RPE noninvasively.

Estimating the performance of lithium beam measurements of current density and electron density in an H-mode pedestal.

The lithium beam is an effective diagnostic tool for investigation of stability and particle transport in the pedestal. It was used successfully to measure edge current density on DIII-D, achieving qualitative agreement with neoclassical models. Electron density profiles were also measured. Proposed upgrades will continue these measurements with higher reliability as well as explore edge current measurements using spectroscopy. The optics will be redesigned to optimize throughput and aperture broadening and to replace the photomultiplier tubes with avalanche photodiodes. The new system will yield detailed measurements of the pedestal, complementing existing diagnostics for investigating pedestal stability, edge localized mode cycle, and particle transport through the pedestal.

MiR-425 involves in the development and progression of renal cell carcinoma by inhibiting E2F6.

OBJECTIVE: To investigate the effect of miR-425 on the proliferation and apoptosis of clear cell renal carcinoma (ccRCA) cells, and to explore the underlying mechanism. PATIENTS AND METHODS: A total of 80 pairs of human clear cell renal carcinoma (ccRCA) and cancer-adjacent normal tissue samples were collected in this study. Human ccRCA cell line (786-O) and normal human kidney cell line (HK-2) were used in cellular research. The expression level of miR-425 was detected in ccRCA tissues and cells, respectively. Target genes of miR-425 were predicted by bioinformatics and verified by luciferase reporter gene assay. Moreover, the role of miR-425 in regulating E2F6 as well as its effect on the proliferation and apoptosis of ccRCA cells were detected. RESULTS: Quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) results showed that the expression of miR-425 was significantly decreased in ccRCA tissues and cells. The proliferation ability and cell cycle of 786-O cells were significantly inhibited after miR-425 overexpression. The percentage of cells in G0/G1 phase was remarkably increased, while the percentage of cells in S and G2/M phases was significantly decreased. Besides, the number of apoptotic cells was significantly increased in the miR-425 intervention group. On-line target gene prediction software indicated that E2F6 was the potential downstream target gene of miR-425. RT-PCR, Western blotting and luciferase reporter gene assay demonstrated that the expression of E2F6 was negatively regulated by miR-425. In addition, subsequent experiments showed that the up-regulation of E2F6 could suppress the inhibitory effect of miR-425 on the proliferation and apoptosis of ccRCA cells. CONCLUSIONS: Our research demonstrated the inhibitory function of miR-425 in ccRCA. Therefore, the miR-425/E2F6 axis was expected to be one of the targets of ccRCA targeted therapy.

Free-breathing coronary CT angiography using 16-cm wide-detector for challenging patients: comparison with invasive coronary angiography.

AIM: To investigate the superiority of free-breathing coronary computed tomography angiography (CCTA) with 16-cm wide-detector CT for challenging patients who cannot hold their breath. MATEIALS AND METHODS: A total of 76 patients (62% with either heart rate >75 beats/min or arrhythmia) who were unable to breath-hold underwent both free-breathing CCTA and invasive coronary angiography (ICA) were included. Two reviewers evaluated coronary arteries on a per-segment, per-vessel, and per-patient basis for image quality using a four-point scale and stenosis degree. CCTA results were compared with ICA to calculate the diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). RESULTS: Out of 1,368 segments, 228 (16.7%) were <1.5 mm in diameter and were excluded. Thirty-two (2.3%) with calcification and 26 (1.9%) with motion artefacts were considered positive at CT. One thousand and eighty-two segments (79.1%) were evaluated both on CCTA and ICA, and 128 (11.8%) segments had ≥50% stenosis on ICA. The diagnostic accuracy, sensitivity, specificity, PPV, and NPV of CCTA were 90.8%, 88.3%, 91.1%, 57.1%, and 98.3% on a per-segment basis; 93.4%, 90.6%, 94.2%, 80.5% and 97.4% on a per-vessel basis; and 92.1%, 100%, 85%, 85.7% and 100% on a per-patient basis. For patients with high heart rates or arrhythmia, 81% (versus 79.1%) segments were evaluable, and the accuracy, sensitivity, specificity, PPV, and NPV were statistically the same as the entire study population. CONCLUSION: Free-breathing CCTA using 16-cm wide-detector CT has high accuracy compared to ICA for detecting coronary artery stenosis for challenging patients.

[Progress in clinical research of IgG4 related diseases in otology].

Summary Immunoglobulin G4-related disease is a systemic idiopathic inflammatory lesion.It is mainly characterized by infiltration of dense IgG4-positive plasma cells,typical storiform fibrosis,obliterative phlebitis and increased serum levels of IgG4.Patients with IgG4-related disease have frequently multiple organs involvement including structural damages of head and neck.But reports of temporal bone involvement in this kind of disease are rarely seen.This article reviews the recent progress in clinical research of lgG4-related disease in otology.

Three-dimensional magnetic resonance pelvimetry: A new technique for evaluating the female pelvis in pregnancy.

OBJECTIVE: To describe three-dimensional (3D) magnetic resonance imaging (MRI) pelvimetry methods and to establish the pelvimetric reference in a large population of Chinese females at term pregnancy. METHODS: Three-hundred one pregnant women at term who underwent MRI were included. Three-dimensional pelvic models were reconstructed using Mimics. 10.0 software based on MRI data sets, and measurements of these models were made. Pelvimetric results according to delivery modality were presented. Additionally, the previously described CT 3D pelvimetry method for predicting cephalopelvic disproportion (CPD) was used to validate its accuracy. RESULTS: Two hundred ten women underwent vaginal delivery, and 13 underwent caesarean delivery for CPD. 3D modelling of the pelvis of pregnant women was feasible using MR data sets. Pelvimetric parameters in the vaginal delivery group were as follows: transverse diameter, 134.7 mm ±â€¯7.5; obstetric conjugate, 126.9 mm ±â€¯8.3; interspinous distance, 113.4 mm ±â€¯8.2; sagittal midpelvis, 117.8 mm ±â€¯8.1; intertuberous distance, 127.1 mm ±â€¯10.4; sagittal outlet, 110.2 mm ±â€¯8.9, and posterior sagittal outlet, 59.7 mm ±â€¯8.1. According to the previously described CT 3D pelvimetry method for predicting CPD, 67.6% (142/210) of women in the vaginal delivery group were diagnosed with CPD. CONCLUSION: 3D MR pelvimetry is a novel method for determining pelvic dimensions at term pregnancy. A prospective trial is needed to establish a useful value for predicting CPD in Chinese females at high risk of CPD.

Saccharomyces cerevisiae Hog1 MAP kinase pathway is activated in response to honokiol exposure.

AIM: The goal of the study was to investigate the cellular tolerance mechanism in response to honokiol exposure. METHODS AND RESULTS: The broth microdilution method was employed to test the sensitivity of different Saccharomyces cerevisiae strains to honokiol. Intracellular levels of reactive oxygen species (ROSs) were determined by DCFH-DA staining. The phosphorylation of Hog1 was evaluated by Western blot analysis. The mRNA expressions of genes involved in the Ras-cyclic AMP (cAMP) pathway were analysed by real-time reverse transcription polymerase chain reaction. We found that the sod1▵ mutant was hypersensitive to honokiol and produced more ROS compared with wild-type and sod2▵ cells. Hog1 was phosphorylated in response to honokiol exposure and deletion of HOG1 increased the sensitivity to honokiol. The expressions of genes involved in the Ras-cAMP pathway were down-regulated after honokiol exposure; exogenous cAMP significantly reduced the phosphorylation of Hog1, although the level was higher than the control level. CONCLUSIONS: In addition to SOD1, the Ras-cAMP cascade and Hog1 MAP kinase pathway is essential for protecting against honokiol-induced oxidative stress. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results provide insight into the understanding of the action mechanism of honokiol.

Development of separation techniques for analysis of Nb-94 in radwaste samples.

A chemical separation technique for removing interfering gamma-ray radionuclides by combined precipitation of Nb pentoxide and anion exchange was proposed, thereby allowing detection of trace 94Nb in low-level radwastes. The detection limit for 94Nb was improved by a factor of 10-103, and the scaling factor (94Nb/60Co) of the radwastes was estimated to be less than 10-5. This technique can be used for low-level radwaste classification and power reactor decommissioning.

Simultaneous detection of 45 fusion genes in leukemia by dual-color fluorescence real-time PCR.

INTRODUCTION: Detection of recurrent genetic abnormalities is of great significance for a refined diagnosis and assessment of prognosis in leukemia. Conventional nested reverse transcription PCR is labor intensive and time-consuming. METHODS: We have developed a novel dual-color TaqMan probe-based real-time PCR method for the simultaneous screening of 45 fusion transcripts in 12 parallel reactions. The method was tested and validated with cell lines carrying known fusion transcripts and patient samples. RESULTS: A multiplex real-time PCR method was successfully developed for rapid detection of 45 fusion genes and validated for 15 of the more commonly detected fusion genes. Intra-assay reproducibility assessed for the most frequent rearrangements ranged from 0.41% to 0.74% for the coefficient of variation (CV) of cycle threshold (Ct) and the interassay reproducibility ranged from 1.62% to 2.83% in five separate experiments. The lowest detection limit for the translocations tested ranged between 1 : 16 000 and 1 : 32 000. Validation of the method with 213 patient samples showed 100% specificity and excellent consistence with conventional nested RT-PCR. CONCLUSION: Overall, we believe that this method is easily applicable, cost-effective, and clinically useful for a rapid screening of fusion genes in the initial diagnostic phase of leukemia. Its use can also be extended to the monitoring of minimal residual disease.

In utero exposure of high-dose di- n-butyl phthalate resulted in opposite effects on testicular cell apoptosis in late embryonic and pubertal male rat offspring.

OBJECTIVE: To investigate the effects of in utero exposure to high-dose di- n-butyl phthalate (DBP) on testicular cell apoptosis in late embryonic and pubertal male rat offspring. METHODS: Twenty pregnant Sprague-Dawley (SD) rats were divided into two groups. During gestation day (GD) 12 to GD 19, control group was given 1 ml day-1 of olive oil and experimental group was given DBP 500 mg kg-1 day-1 by gavage. On GD 19.5 and postnatal day (PND) 45, the testes were removed. Morphological analysis of the testes was observed by transmission electron microscopy and hematoxylin and eosin (H&E) staining. Testicular cell apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL). The expression of Bcl-2, Bax, and p53 was presented by immunohistochemistry (IHC) and western blot. Data of the two groups was compared using independent samples t-test and Mann-Whitney test by SPSS 20.0. RESULTS: H&E staining showed that spermatogenetic cells were significantly decreased in DBP exposed pubertal rat testis. The apoptosis index of testes in DBP-treated group was significantly lower on GD 19.5 but higher on PND 45 than that of the controls ( p < 0.01). IHC and western blot revealed significantly increased expression of Bcl-2 in GD 19.5 rat testis and Bax and p53 in PND 45 rat testis after DBP exposure, compared with the control ( p < 0.05). CONCLUSION: In utero exposure of high-dose DBP resulted in opposite effects on testicular cell apoptosis in late embryonic and pubertal rat offspring. The overexpression of Bcl-2, Bax, and p53 might be related to the occurrence of abnormal apoptosis and finally produce male infertility.