Concentrations and distribution of novel brominated flame retardants in the atmosphere and soil of Ny-Ålesund and London Island, Svalbard, Arctic

Novel brominated flame retardants (NBFRs) were investigated in Arctic air and soil samples collected from Ny-Ålesund and London Island, Svalbard, during Chinese scientific research expeditions to the Arctic during 2014-2015. The concentrations of Σ₉NBFRs in the Arctic air and soil were 4.9-8.7 pg/m³ (average 6.8 pg/m³) and 101-201 pg/g dw (average 150 pg/g dw), respectively. The atmospheric concentration of hexabromobenzene (HBB) was significantly correlated with that of pentabromotoluene (PBT) and pentabromobenzene (PBBz), suggesting similar source and environmental fate in the Arctic air. No significant spatial difference was observed among the different sampling sites, both for air and soil samples, indicating that the effects of the scientific research stations on the occurrence of NBFRs in the Arctic were minor. The fugacities from soil to air of pentabromoethylbenzene (PBEB), 2,3-dibromopropyl 2,4,6-tribromophenyl ether (DPTE), and decabromodiphenylethane 1,2-bis (pentabromophenyl) ethane (DBDPE) were lower than the equilibrium value, indicating a nonequilibrium state of these compounds between air and soil, the dominant impact of deposition and the net transport from air to soil. The correlation analysis between the measured and predicted soil-atmosphere coefficients based on the absorption model showed that the impact of the soil organic matter on the distribution of NBFRs in the Arctic region was minor. To the best of our knowledge, this work is one of the limited reports on atmospheric NBFRs in the Arctic and the first study to investigate the occurrence and fate of NBFRs in the Arctic soil.

Comparing nanoparticle polymeric micellar paclitaxel and solvent-based paclitaxel as first-line treatment of advanced non-small-cell lung cancer: an open-label, randomized, multicenter, phase III trial

BACKGROUND

Polymeric micellar paclitaxel (pm-Pac) is a novel Cremophor EL-free, nanoparticle micellar formulation of paclitaxel. We aimed to compare the efficacy and safety between pm-Pac plus cisplatin and solvent-based paclitaxel (sb-Pac) plus cisplatin in advanced non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

A total of 448 stage IIIB to IV NSCLC patients were randomly assigned (2:1) to receive six 3-week cycles of either pm-Pac (230 mg/m²) plus cisplatin (70 mg/m²; n = 300), followed by dose escalation of pm-Pac to 300 mg/m² from the second 3-week cycle if prespecified toxic effects were not observed after the first cycle, or sb-Pac (175 mg/m²) plus cisplatin (70 mg/m²; n = 148). The primary end point was objective response rate (ORR) assessed by independent review committees (IRCs). The secondary end points included IRC-assessed progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

Patients in the pm-Pac-plus-cisplatin group showed significant improvements in IRC-assessed ORR compared with those in the sb-Pac-plus-cisplatin group (50% versus 26%; rate ratio 1.91; P < 0.0001). Additionally, subgroup analysis showed that a higher ORR was consistently observed in both squamous and nonsquamous histological types. IRC-assessed median PFS was significantly higher in the pm-Pac-plus-cisplatin group than in the sb-Pac-plus-cisplatin group (6.4-month versus 5.3-month; hazard ratio 0.63; P = 0.0001). Median OS was not significantly different between the two groups. The incidence of treatment-related serious adverse events (9% versus 18%; P = 0.0090) was significantly lower in the pm-Pac-plus-cisplatin group than in the sb-Pac-plus-cisplatin group.

CONCLUSION

Pm-Pac plus cisplatin yielded superior ORR and PFS along with a favorable safety profile and should become an option for patients with advanced NSCLC.

CLINICAL TRIAL IDENTIFIER

ClinicalTrials.gov NCT02667743; https://clinicaltrials.gov/ct2/show/NCT02667743.

MicroRNA-579-3p promotes the progression of osteoporosis by inhibiting osteogenic differentiation of mesenchymal stem cells through regulating Sirt1

OBJECTIVE

To explore whether microRNA-579-3P was involved in the development of osteoporosis, and to investigate the possible molecular mechanisms.

PATIENTS AND METHODS

The messenger RNA (mRNA) expression levels of microRNA-579-3P, alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX2) and bone sialoprotein (BSP) in serum samples of osteoporosis patients and normal controls were detected by quantitative Real-time polymerase chain reaction (qRT-PCR), respectively. Meanwhile, the expressions of the above genes during osteogenic differentiation of human bone marrow mesenchymal stem cells (hMSCs) were examined as well. To investigate the effect of microRNA-579-3P on osteogenesis, microRNA-579-3P was overexpressed and knocked down in hMSCs. Subsequently, the mRNA and protein expression levels of osteogenesis-related genes, such as ALP, RUNX2 and BSP, were detected by qRT-PCR and Western blot, respectively. In addition, ALP activity and mineralization forming ability were evaluated by ALP staining and alizarin red staining. Bioinformatics predicted that Sirt1 was the target gene of microRNA-579-3P. Subsequent luciferase reporter gene assay was performed to verify the binding relationship of microRNA-579-3P to Sirt1. Meanwhile, qRT-PCR and Western blot were used to detect the changes in the mRNA and protein expression levels of Sirt1, respectively. After overexpression of microRNA-579-3P and Sirt1, qRT-PCR, Western blot, ALP staining and alizarin red staining assays were performed to detect the osteogenic differentiation of hMSCs.

RESULTS

The expression of microRNA-579-3P in serum of patients with osteoporosis was significantly higher than that of normal controls. Meanwhile, the expression of microRNA-579-3P decreased gradually during osteogenic differentiation of hMSCs. Overexpression of microRNA-579-3P significantly reduced the expressions of osteogenic related genes, including ALP, RUNX2 and BSP. Besides, ALP activity and mineralized nodule formation ability decreased obviously as well. Luciferase reporter gene assay showed that microRNA-579-3P could bind to Sirt1. After overexpression of microRNA-579-3P, the mRNA and protein expression levels of Sirt1 were significantly reduced, which were reversed after silence of microRNA-579-3P. Simultaneous overexpression of microRNA-579-3P and Sirt1 could reverse the inhibition of osteogenic differentiation of hMSCs caused by overexpression of microRNA-579-3P alone.

CONCLUSIONS

MicroRNA-579-3P could inhibit osteogenic differentiation of hMSCs by regulating Sirt1, thereby promoting the development of osteoporosis.

Genome-wide Analyses Identify a Novel Risk Locus for Nonsyndromic Cleft Palate

The 3 major subphenotypes observed in patients with nonsyndromic orofacial clefts (NSOFCs) are nonsyndromic cleft lip only (NSCLO), nonsyndromic cleft lip with palate (NSCLP), and nonsyndromic cleft palate only (NSCPO). However, the genetic architecture underlying NSCPO is largely unknown. Here we performed a 2-stage genome-wide association study (GWAS) on NSCPO and replication analyses of selected variants in other NSOFCs from the Chinese Han population. We identified a novel locus (15q24.3) and a known locus (1q32.2) where variants in or near the gene reached genome-wide significance (2.80 × 10^-13 < P < 1.72 × 10^-08) in a test for association with NSCPO in a case-control design. Although a variant from 15q24.3 was found to be significantly associated with both NSCPO and NSCLP, the direction of estimated effects on risk were opposite. Our functional annotation of the risk alleles within 15q24.3 coupled with previously established roles of the candidate genes within identified risk loci in periderm development, embryonic patterning, and/or regulation of cellular processes supports their involvement in palate development and the pathogenesis of cleft palate. Our study advances the understanding of the genetic basis of NSOFCs and provides novel insights into the pathogenesis of NSCPO.

Occurrence and distribution of organophosphate esters in the air and soils of Ny-Ålesund and London Island, Svalbard, Arctic

The levels of eight organophosphate esters (OPEs) were analyzed in air and soil samples collected at Ny-Ålesund and London Island, Svalbard during the Chinese Scientific Research Expedition to the Arctic during 2014-2015. The concentrations of total OPEs (∑OPEs) ranged from 357 pg/m³ to 852 pg/m³ in the air and from 1.33 ng/g to 17.5 ng/g dry weight (dw) in the soils. Non-Cl OPEs accounted for 56 ± 13% and 62 ± 16% of ∑OPEs for the air and soil, respectively. Tris(2-chloroethyl) phosphate (TCEP) was the dominant compound in the air, with an average concentration of 180 ± 122 pg/m³. Triphenyl phosphate, tri(1-chloro-2-propyl) phosphate, and TCEP were the most abundant OPEs in the soils, with mean values of 1.77, 2.13, and 1.02 ng/g dw, respectively. Compared with the levels of polybrominated diphenyl ethers found in Arctic regions in previous studies, OPEs showed significantly higher concentrations, thereby indicating the large production and wide usage of OPEs globally. In addition, the fugacity fraction results indicated that net deposition from air to soil was dominated in the area. Overall, the occurrence and distribution of OPEs in the air and soils in the Arctic region indicated that OPEs can undergo long-range atmospheric transport and accumulate in remote regions.

Erratum: Evolution of π^{0} Suppression in Au+Au Collisions from sqrt[s_{NN}]=39 to 200 GeV [Phys. Rev. Lett. 109, 152301 (2012)]

This corrects the article DOI: 10.1103/PhysRevLett.109.152301.

Novel brominated flame retardants in West Antarctic atmosphere (2011-2018): Temporal trends, sources and chiral signature

Novel brominated flame retardants (NBFRs) were comprehensively investigated in both gaseous and particle phase samples collected using a high-volume active air sampler (HV-AAS) at the Chinese Great Wall Station in King George Island, West Antarctica from 2011 to 2018. The concentrations of ∑₁₂NBFRs ranged from 0.27 to 3.0 pg m^-3, with a mean value of 1.1 ± 0.50 pg m^-3 and the levels showed a slightly increasing trend over the eight years. Decabromodiphenyl ethane (DBDPE) was the predominant NBFR with a relative contribution of 50% on average. Most of the studied NBFRs tended to distribute in gaseous phase with an average ratio of 72 ± 16% while NBFRs with higher log K_OA values had higher proportions in particle phase. The gas/particle partitioning models were employed to evaluate the environmental behavior of NBFRs. Compared to the equilibrium-state-based model, the steady-state-based model performed much better to predict the gas/particle partitioning of NBFRs in the West Antarctic atmosphere. Additionally, no temperature dependence was found for NBFRs except rac-(1R,2R,5R,6R)-1,2,5,6-tetrabromocyclooctane (β-TBCO). The annual mean concentrations of ∑₁₂NBFRs showed a significantly negative correlation with the frequency of east-southeast (ESE, 112.5°) wind and calm wind (~0 m s^-1) (p < 0.05), and a significantly positive correlation with the frequency of wind from northwest interval (west to north-northwest, 270° to 337.5°) (p < 0.05), suggesting a significant effect of air mass from the ocean area. Furthermore, the chiral signature of NBFRs showed commonly non-racemic residue in the atmosphere. The enantiomer fractions (EF) of rac-(1R,2R)-1,2-dibromo-(4S)-4-((1R)-1,2-dibromoethly)cyclohexane (α-TBECH) and β-TBCO were 0.115-0.962 and 0.281-0.795, revealing secondary sources of NBFRs, e.g., seawater-air exchange and/or non-racemic residue in the source regions. As far as we know, this is one of very few studies on NBFRs in the Antarctic atmosphere.

OP0090 EFFICACY OF SUBCUTANEOUS TANEZUMAB FOR THE TREATMENT OF CHRONIC LOW BACK PAIN: AN ANALYSIS OF BRIEF PAIN INVENTORY-SHORT FORM SCORES FROM A 56-WEEK, RANDOMIZED, PLACEBO- AND TRAMADOL-CONTROLLED, PHASE 3 TRIAL

Background:

Tanezumab, a monoclonal antibody against nerve growth factor, was recently evaluated in an 80 week placebo and tramadol-controlled trial in patients with chronic low back pain (CLBP) and a history of inadequate response to standard-of-care analgesics (NSAIDs, opioids, etc). Primary endpoint was change in Low Back Pain Intensity (LBPI) at week 16 vs placebo. Key secondary endpoints were the proportion of patients with ≥50% improvement in LBPI at week 16, change in Roland Morris Disability Questionnaire score at week 16, and change in LBPI at week 2 (all vs placebo). Tanezumab 10mg met the primary and all key secondary endpoints. Tanezumab 5mg did not meet the primary endpoint, but improved 2 of 3 key secondary endpoints. Due to the primary endpoint result and the statistical gate-keeping approach to control for multiple comparisons, a conclusion of superiority over placebo could not be made for the 5mg dose.

Objectives:

To further characterize tanezumab’s effects on pain and function in this trial through analysis of Brief Pain Inventory-short form (BPI-sf) scores.

Methods:

Patients received placebo (n=406), subcutaneous (SC) tanezumab 5mg (every 8 weeks; n=407), SC tanezumab 10mg (every 8 weeks; n=407) or oral tramadol prolonged-release (100-300mg/day; n=605). Pre-specified secondary endpoints included BPI-sf worst pain, average pain, the overall pain interference index, and selected individual domains of the index (general activity, walking ability, sleep, and normal work). Least squares (LS) mean (standard error [SE]) changes from baseline in BPI-sf scores were compared between groups (unadjusted for multiplicity) at week 16 using an analysis of covariance model. Scores range from 0-10 with higher scores indicating greater pain severity or functional impairment.

Results:

LS mean (SE) differences from placebo for worst pain were -0.52 (0.19) for tanezumab 5mg (p≤0.01), -0.54 (0.19) for tanezumab 10mg (≤0.01), and -0.24 (0.17) for tramadol (p=0.17). LS mean (SE) differences from placebo for average pain were -0.37 (0.18) for tanezumab 5mg (p=0.04), -0.46 (0.18) for tanezumab 10mg (≤0.01), and -0.17 (0.16) for tramadol (p=0.29). LS mean (SE) differences from placebo for the pain interference index were -0.41 (0.18) for tanezumab 5mg (p=0.03), -0.58 (0.18) for tanezumab 10mg (≤0.01), and -0.15 (0.17) for tramadol (p=0.39). Effects of tanezumab were not statistically different (p>0.05) from tramadol for worst pain, average pain, and the pain interference index, with exception of the pain interference index for tanezumab 10mg (p=0.01). Mean dose of tramadol was 203mg/day at week 16.

Tanezumab 10mg significantly (p<0.05) improved individual domains of the pain interference index (general activity, walking ability, sleep, and normal work) vs placebo and vs tramadol. Tanezumab 5mg significantly (p<0.05) improved pain interference with general activity and normal work vs placebo, and sleep vs placebo and vs tramadol. No statistical differences in any domain was observed for tramadol vs placebo.

Conclusion:

Tanezumab 5mg and 10mg significantly improved worst pain, average pain, and overall pain interference index scores vs placebo in patients with CLBP. Tanezumab 10mg also significantly improved the overall pain interference index vs tramadol. Tanezumab 5mg significantly improved most individual domains of the pain interference index vs placebo, while tanezumab 10mg significantly improved all domains assessed vs placebo and vs tramadol.

Disclosure of Interests:

John Markman Consultant of: Consultant: Trigemina, Editas Medicine, and Plasma Surgical; Advisory board: Clexio Biosciences, Flexion Therapeutics, Quark Pharmaceuticals, Quartet Medicine, Collegium Pharmaceutical, Purdue Pharma, Biogen, Novartis, Aptinyx, Nektar, Allergan, Grünenthal, Eli Lilly and Company, Depomed, Janssen Pharmaceuticals, Teva Pharmaceutical Industries, KemPharm, Abbott Laboratories, Plasma Surgical, Chromocell, Convergence Pharmaceuticals, Inspirion, Pfizer, Sanofi, Daiichi Sankyo, and Trevena; Data safety monitoring boards for Novartis and Allergan, Serge Perrot Consultant of: Grunenthal, Pfizer, Lilly, MSD, Sanofi, Menarini, Seiji Ohtori: None declared, Thomas Schnitzer Consultant of: Pfizer, Lilly, AstraZeneca, GSK, Said Beydoun Grant/research support from: Argenx, Catalyst Pharma, Mallinckrodt, Pfizer, UCB, Consultant of: Alexion, Akcea, Alnylam, CSL, Takeda, Mitsubishi Tanabe, Speakers bureau: Alexion, Akcea, Alnylam, CSL, Takeda, Mitsubishi Tanabe, Lars Viktrup Shareholder of: Eli Lilly and Company, Employee of: Eli Lilly and Company, Ruoyong Yang Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Candace Bramson Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Christine West Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Ken Verburg Shareholder of: Pfizer Inc, Employee of: Pfizer Inc

AB0527 PHARMACOGENETICS AND PHARMACODYNAMICS OF RESPONSE TO APREMILAST IN A PHASE 3 CLINICAL STUDY IN SUBJECTS WITH ACTIVE BEHÇET’S DISEASE

Background:

Apremilast (APR), an oral phosphodiesterase 4 (PDE4) inhibitor, modulates inflammatory mediators1and has demonstrated efficacy in treating oral ulcers in a phase III Behçet’s syndrome study (BCT-002 [RELIEF]).2

Objectives:

To conduct an exploratory analysis of genetic polymorphisms, plasma biomarkers, and blood leukocytes with clinical response in RELIEF.

Methods:

Subjects with active Behçet’s disease (BD) were randomized (1:1) to APR 30 mg twice daily or placebo (PBO). The primary clinical efficacy endpoint was the area under the curve for the number of oral ulcers through Week 12 (AUCWk0-12). Among the 207 subjects enrolled, 140 provided consent for DNA genotyping, 116 for plasma biomarker testing, and 96 for leukocyte subset testing. Genotyping was performed on the Illumina Omni2.5 BeadChip (Covance Genomics Laboratory). TNF-α, IL-6, interferon-γ, and IL-17A levels were measured using Simoa Single Molecule Array; IL-8 and IL-23 were measured using the Human DiscoveryMAP multiplex panel (Myriad RBM). Th17, Treg, and CD3 T cells were counted using bisulfite-specific RT-PCR (Epiontis Gmbh). A rank ANCOVA model was used to estimate between-treatment differences (APR vs. PBO) in percent change from baseline for each biomarker/leukocyte subtype over the 12 weeks of treatment. Within each treatment group, the correlation of percent change from baseline at Week 12 in biomarker/leukocyte subtype with the primary efficacy endpoint AUCWk0-12was examined using a univariate regression model. A separate regression model was used to assess the interaction between treatment and the biomarker/leukocyte subtype clinical response.

Results:

Pharmacogenetic analysis of BD risk variants in HLA-B, IL-10, TLR2, ACE, TNF, GIMAP, PDGFRL, and UBAC2 + 55 genes associated with PDE4 biology yielded no candidate variants that were significantly associated with response to APR or PBO at a Bonferroni-correctedPvalue of 2 x 10−6. Clinical response to APR with respect to HLA-B51 yielded an odds ratio (OR) of 1.21 (95% CI, 0.53-2.75), indicating no significant relationship (Figure 1). Pharmacodynamic changes for IL-6, IL-3, IL-17A, IL-23, and TNF-α were not statistically significant. APR treatment was associated with a significant change in interferon-γ (mean: +107.4%; median: −19.2%) vs. PBO (mean: +78.8%; median: +7.9%) (P=0.0077). Using a univariate regression model, TNF-α showed strong positive correlation with AUCWk0-12in the APR group (r=0.90;P=0.0140); IL-8 had weak positive correlation with AUCWk0-12in the APR group (r=0.04;P=0.0333). A significant negative correlation was observed between the percent change from baseline in the number of Th17 cells and AUCWk0-12in the APR group (r=−0.79;P=0.0392) and a significant positive correlation was observed with the percent change from baseline in the number of Treg cells and AUCWk0-12in the PBO group (r=0.94;P=0.0182). Of all the biomarkers and leukocyte subtypes examined in a regression model using treatment as a factor, only Treg had a statistically significant treatment interaction (P=0.0069).

Conclusion:

Although there were no genetic predictors of clinical response to APR treatment, strong correlation was observed between the percent change from baseline in plasma TNF-α with AUCWk0-12in the APR group. A negative correlation was observed between percent change from baseline in Th17 cells and AUCWk0-12in the APR group and a positive association was observed between Treg cells and AUCW0-12in the PBO group.

References:

[1]Schafer P.Biochem Pharmacol. 2012; 83:1583-1590. 2. Hatemi G, et al. Presented at: ACR/ARHP Annual Meeting; November 8–13, 2019; Atlanta, GA. Presentation 0946.

Disclosure of Interests: :

Joseph Maranville Employee of: Celgene Corporation – employment at the time of study conduct, Irina Medvedeva Employee of: Celgene Corporation – employment at the time of study conduct, Robert Yang Employee of: Celgene Corporation – employment at the time of study conduct, Mindy Chen Employee of: Amgen Inc. – employment; Celgene Corporation – employment at the time of the conduct, Lorraine (Ruoying) Fang Employee of: Celgene Corporation – employment at the time of study conduct, Sandra Collazo Employee of: Amgen Inc. – employment; Celgene Corporation – employment at the time of the conduct, Shannon McCue Employee of: Amgen Inc. – employment; Celgene Corporation – employment at the time of the conduct, Peter Schafer Employee of: Bristol-Myers Squibb – employment; Celgene Corporation – employment at the time of study conduct

Age dependence accumulation of organochlorine pesticides and PAHs in needles with different forest types, southeast Tibetan Plateau

In this study, organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs) in needle leaves with different ages were measured in three prevalent coniferous forests including spruce, fir and pinus in southeast Tibetan Plateau (TP) to investigate accumulation behavior of persistent organic pollutants (POPs) during entire growth cycle of needles. The accumulation concentration of POPs was higher in pinus and fir needles than in spruce needles. Concentrations for most of OCPs significantly increased with needle ages, especially dichlorodiphenyltrichloroethane (DDT) and its metabolites showed more remarkable increasing trend than hexachlorocyclohexane isomers (HCHs) and hexachlorobenzene (HCB) in the three tree species. However, age dependence accumulation of PAHs was not observed in most cases, possibly due to its easier degradation property and the influence by dramatic change of ambient atmospheric concentration of PAHs. The lipid normalized concentrations in needles exhibited similar accumulation pattern with that of dry weight basis. The controlling factors for concentration variation in needles were identified using multiple linear regression. The suitability of these needle species acting as potential passive sampler for atmospheric POPs was evaluated. The different-age needles could reflect atmospheric OCP concentrations in the past long-term trend. Findings of this study provide guidance in use of needle as passive samples for the background monitoring of the atmospheric contamination at remote and poorly accessible locations such as the TP.

Spin-Canting-Induced Band Reconstruction in the Dirac Material Ca_{1-x}Na_{x}MnBi_{2}

The ternary AMnBi_{2} (A is alkaline as well as rare-earth atom) materials provide an arena for investigating the interplay between low-dimensional magnetism of the antiferromagnetic MnBi layers and the electronic states in the intercalated Bi layers, which harbor relativistic fermions. Here, we report on a comprehensive study of the optical properties and magnetic torque response of Ca_{1-x}Na_{x}MnBi_{2}. Our findings give evidence for a spin canting occurring at T_{s}∼50-100  K. With the support of first-principles calculations we establish a direct link between the spin canting and the reconstruction of the electronic band structure, having immediate implications for the spectral weight reshuffling in the optical response, signaling a partial gapping of the Fermi surface, and the dc transport properties below T_{s}.

Rapamycin-induced autophagy plays a pro-survival role by enhancing up-regulation of intracellular ferritin expression in acute lymphoblastic leukemia

Elevated mammalian target of rapamycin (mTOR) signaling has been reported to correlate with poor prognosis in acute lymphoblastic leukemia (ALL) patients. Rapamycin, an mTOR kinase inhibitor, and also a potent autophagy inducer, could not only effectively reverse glucocorticoid resistance, but also promote autophagy in the ALL cells. Autophagy has been suggested to play a paradoxical role in cancer treatment. The aim of this study was to address the role of the rapamycin-induced autophagy in the leukemia treatment.

MATERIALS AND METHODS

Cell proliferation was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay in ALL cell lines of CEM-C1 and CEM-C7. Western Blot analysis was performed to test protein expressions.

RESULTS

Inhibition of mTOR by rapamycin could reverse glucocorticoid resistance in CEM-C1 cells, and also induce autophagy in these cells by up-regulation of LC3-II and Beclin-1 expressions. This autophagy played a pro-survival role since its inhibition by 6-amino-3-methylpurine or chroloquine could enhance rapamycin-induced cell death. Rapamycin increased the expression of intracellular ferritin, and this effect could be totally blocked by 6-amino-3-methylpurine and chroloquine, suggesting that the protective role of autophagy might be mediated through up-regulation of ferritin, the major iron-binding stress protein. Ciclopirox olamine, an iron chelator, could enhance rapamycin's anti-leukemia effect by down-regulation of intracellular ferritin expression.

CONCLUSIONS

All these findings would suggest that rapamycin-induced autophagy plays a pro-survival role in leukemia cells and this effect might be mediated by up-regulation of intracellular ferritin expression. We hypothesize that the combination of mTOR pathway inhibitors and autophagy inhibition is rational and would induce strong anti-leukemia effects in ALL.

CTXA hip: the effect of partial volume correction on volumetric bone mineral density data for cortical and trabecular bone

This study compares the results of computed tomography X-ray absorptiometry (CTXA) hip volumetric BMD (vBMD) analyses of cortical and trabecular bone with and without partial volume correction. For cortical bone in some circumstances, corrected cortical volumes were negative and corrected vBMD was very high. For trabecular bone, the correction effects are smaller. CTXA volumetric data should be interpreted with caution.

PURPOSE

Previous studies have reported concerns about the reliability of CTXA hip cortical vBMD measurements generated using partial volume (PV) correction (the "default" analysis, with cortical PV correction). To date, no studies have examined the results of the alternative ("new") analysis (with trabecular PV correction). This study presents in vivo and phantom data comparing the corrected and uncorrected data for cortical and trabecular bone respectively.

METHODS

We used the commercial QCTPro CTXA software to analyze CT scans of 129 elderly Chinese men and women and an anthropomorphic European Proximal Femur phantom (EPFP) and accessed data for two alternative scan analyses using the database dump utility. The CTXA software gives the user two methods of performing the PV correction: (1) a default analysis in which only cortical bone results are corrected; (2) a new analysis in which only trabecular bone results are corrected. Both methods are based on a numerical recalculation of vBMD values without any change in volume of interest (VOI) placement.

RESULT

In vivo, the results of the two analyses for integral bone were the same while cortical and trabecular results were different. PV correction of cortical bone led to a decrease of cortical volume for all four VOIs: total hip (TH), femoral neck (FN), trochanter (TR), and intertrochanter (IT) volumes were reduced on average by 7.8 cm³, 0.9 cm³, 2.5 cm³, and 4.3 cm³ respectively. For TR, where cortex was thinnest, average corrected cortical volume was negative (- 0.4± 1.3 cm³). Corrected cortical vBMD values were much larger than uncorrected ones for TH, FN, and IT. Scatter plots of corrected cortical vBMD against cortical bone thickness showed that elevated results correlated with thinner cortices. When trabecular bone was corrected for the PV effect, trabecular volumes of TH, FN, TR, and IT were reduced on average by 7.9 cm³, 0.8 cm³, 2.6 cm³, and 4.4 cm³ respectively, while vBMD measurements were increased correspondingly. The trabecular volume and vBMD measurements of the two datasets both had highly positive correlations. For the EPFP, the PV-corrected FN data deviated from the nominal phantom value, but was closer for the TR and IT VOIs. Both corrected and uncorrected data overestimated trabecular vBMD, with the corrected results showing greater deviation from nominal values.

CONCLUSION

The default and new CTXA analyses for volumetric data generate different results, both for cortical and trabecular bone. For cortical bone, the uncorrected results are subject to partial volume effects but the correction method of the default analysis overcorrects the effect leading to in part unreasonable results for cortical bone volume and BMD. For trabecular bone, the correction effects are smaller. CTXA volumetric data should be interpreted with caution.

Porphyromonas gingivalis Induces Insulin Resistance by Increasing BCAA Levels in Mice

Insulin resistance is one of the critical pathogeneses of type 2 diabetes mellitus (T2DM). Elevated levels of plasma branched-chain amino acids (BCAAs) are associated with insulin resistance. Recent studies have demonstrated the role of Porphyromonas gingivalis in the development of insulin resistance. However, the mechanisms by which P. gingivalis induces insulin resistance are still unclear. The purpose of this study was to investigate whether P. gingivalis induces insulin resistance through BCAA biosynthesis. We established a murine model of periodontitis by infecting mice with P. gingivalis. Alveolar bone loss, insulin sensitivity, and the plasma level of BCAAs were measured. A P. gingivalis BCAA aminotransferase-deficient strain (∆bcat) was constructed, and its kinetic growth, biofilm formation, and in vivo colonization were compared with its wild-type strain. Alveolar bone loss, insulin sensitivity, and the plasma level of BCAAs of the mice infected with either wild-type strain or ∆bcat strain were further measured. We found that periodontal infection with P. gingivalis significantly upregulated the plasma level of BCAAs and aggravated the high-fat diet (HFD)-induced insulin resistance. Bcat deletion did not alter the growth, biofilm formation, and in vivo colonization of P. gingivalis. More important, the ∆bcat strain was unable to upregulate the plasma level of BCAAs and induce insulin resistance in HFD-fed mice. These findings suggest that the BCAA biosynthesis of P. gingivalis plays a critical role in the development of insulin resistance in the HFD-fed mice. The BCAA biosynthesis pathways may provide a potential target for the disruption of linkage between periodontitis and T2DM.

Exposure to organochlorine pesticides and the risk of type 2 diabetes in the population of East China

Organochlorine pesticides (OCPs) have been reported to be associated with an elevated risk of type 2 diabetes, although no study has focused on such associations in Chinese populations. In this case-control study, we aimed to explore the associations between OCPs and type 2 diabetes and their potential mechanisms in a population from East China. Participants diagnosed with type 2 diabetes and nondiabetic participants from Shandong Province, East China, were enrolled in this case-control study. Six OCPs (β-HCH, trans-chlordane, trans-nonachlor, p,p'-DDE, p,p'-DDT and mirex/kepone) were detected in more than 75% of serum samples. Logistic regression analysis and multiple linear regression analysis were used to assess the associations between OCP exposure and the outcomes. After adjusting for potential confounding factors such as age, sex and body mass index, all six OCPs showed positive associations with type 2 diabetes in a linear dose-response manner. Serum concentrations of β-HCH and p,p'-DDE were associated with higher levels of fasting plasma glucose in participants without diabetes, although no OCPs showed significant associations with hemoglobin A1c. In addition, certain OCPs showed significantly positive associations with triglycerides, total cholesterol, and low-density lipoprotein cholesterol and negative relationships with high-density lipoprotein cholesterol in nondiabetics, indicating that OCP exposure may disrupt lipid metabolism. Findings in the current study indicated that OCPs may be a diabetogenic factor in the population of this study. To our knowledge, this is the first study to investigate the associations between OCP exposure and type 2 diabetes in a Chinese population.

Feasibility of energy adaptive angular meshing for perpendicular and parallel magnetic fields in a grid based Boltzmann solver

PURPOSE

To develop the enabling algorithmic techniques which allow forward-peaked adaptive angular meshing to be compatible with angular advection of magnetic fields within a deterministic Grid Based Boltzmann Solver (GBBS) for MRI-guided radiotherapy, and establish appropriate energy adaptive meshing schemes which minimize total numerical degrees of freedom while preserving high dosimetric accuracy for parallel and perpendicular magnetic fields.

METHODS

A framework to independently adapt angular mesh resolution and basis function refinement of forward and backscattering hemispheres is developed, uniquely accommodating angular advection introduced by magnetic fields. Upwind stabilization techniques to accurately transfer fluence between hemispheres having different discretization are established. To facilitate oblique beam and magnetic field orientations, cardinal forward-peaked mesh orientations were devised to balance requirements for acyclic space-angle sweep ordering, while ensuring the beam predominantly overlaps the forward hemisphere. Energy-dependent fluence anisotropy is investigated, leading to adaptive angular meshing schemes for parallel and perpendicular magnetic fields. Calculated dose distributions were validated against GEANT4 Monte Carlo calculations on slab geometry and anthropomorphic phantoms.

RESULTS

Forward-peaked and isotropic energy adaptive angular meshing schemes were developed for parallel and perpendicular magnetic fields respectively, which reduce the number of elements solved by 52.8% and 47.7% respectively compared to static discretization using 32 quadratic elements while retaining over 97% of points passing the gamma 1%/1 mm criterion against Monte Carlo.

CONCLUSIONS

Techniques to preserve angular upwind-stabilization between hemispheres of a forward-peaked mesh and establish an acyclic directed space-angle sweep graph enabled energy-adaptive meshing schemes to be developed while accurately solving for magnetic fields. This substantially reduced the numerical degrees of freedom while retaining excellent dosimetric agreement with Monte Carlo. These algorithmic underpinnings contribute towards a fast deterministic GBBS for MRI-guided radiotherapy.

[Interaction of health literacy and second-hand smoke exposure on psychopathological symptoms of middle school students]

Objective: To explore the interaction of health literacy and second-hand smoke exposure on psychopathological symptoms of middle school students. Methods: From November 2015 to January 2016, 22 628 middle school students from Shenyang of Liaoning Province, Bengbu of Anhui Province, Xinxiang of Henan Province, Ulanqab of Inner Mongolia Autonomous Region, Chongqing Municipality, and Yangjiang of Guangdong Province were enrolled by using the multi-stage cluster convenience sampling method. A questionnaire was used to collect the data including demographic information, health literacy, second-hand smoke exposure, and psychopathological symptoms. A multivariate logistic regression model was used to analyze the interaction of health literacy and second-hand smoke exposure on psychopathological symptoms of middle school students. Results: The age of students was (15.36±1.79) years old, of which 10 990 were boys, accounting for 48.6% of total students. The detection rate of psychopathological symptoms was 29.1% (6 581/22 628). The detection rate of psychopathological symptoms in those who were exposed to second-hand smoke was 38.1% (2 401/6 304), which was higher than that in the non-second-hand smoke exposure group [25.6% (4 180/16 324)] (P<0.001). The OR (95%CI) of the interaction between medium and low levels of overall health literacy, low level of interpersonal dimension of health literacy and second-hand smoke exposure was 1.19 (1.15-1.24), 2.00 (1.92-2.10) and 1.59 (1.52-1.66), respectively. Conclusion: There was a positive interaction between middle and low levels of overall health literacy, low level of interpersonal dimension of health literacy and second-hand smoke exposure on psychopathological symptoms of middle school students.

Associations between the exposure to persistent organic pollutants and type 2 diabetes in East China: A case-control study

Persistent organic pollutants (POPs) have been associated with a high risk of type 2 diabetes in different regions, although few studies from China have been published. We aimed to investigate the associations between POP exposure and type 2 diabetes in Chinese population. A total of 158 participants diagnosed with type 2 diabetes and 158 participants without the disorder from Shandong Province were enrolled in this case-control study during 2016-2017. Nine polychlorinated biphenyl congeners (PCBs) and 2 polybrominated diphenyl ethers with detectable levels in ≥75% of the participants were selected for data analysis. The results showed that POP exposure was significantly and positively associated with the risk of diabetes after adjusting for age, sex, BMI, triglycerides and total cholesterol. However, we did not observe an obvious modified effect of adiposity on the associations between POP exposure and diabetes in the present study, as strong associations between POPs and diabetes were observed in both the higher-BMI (BMI≥25 kg/m²) and the lower-BMI (BMI<25 kg/m²) groups. POPs showed stronger associations with diabetes in males than in females. The odds ratio (OR) for the highest quartile of ∑POPs was 6.97 for males, nearly two times higher than that for females (OR = 3.58). All these findings suggest that POP exposure may impact the risk of diabetes in Chinese population.