Total serum cholesterol by isotope dilution/mass spectrometry: a candidate definitive method

We describe a highly accurate and precise method for determination of total cholesterol in serum by isotope dilution/mass spectrometry. The method was developed for a Study Group of the Committee on Standards of the American Association for Clinical Chemistry, for use in establishing the accuracy of a candidate reference method for total cholesterol, and fulfills their criteria for a definitive method. Cholesterol-d7 is added to serum, with the weight ratio of cholesterol-d7 to total serum cholesterol kept near to 1:1. The esters are hydrolyzed and the cholesterol is separated and converted into the trimethylsilyl ether derivative for measurement by combined gas chromatography/mass spectrometry. The intensity ratio of the molecular ions at m/z 465 and 458 is measured for each sample and for two calibration mixtures, according to a prescribed bracketing protocol. A weight ratio for the sample is obtained by linear interpolation of the ion-intensity ratios, and the total cholesterol is then calculated. The method was applied four times over several weeks to each of five serum pools. Statistical analysis involving consideration of both replication error and variability between weeks gave a coefficient of variation for a single measurement of 0.36%. The absence of interferences in the method was demonstrated by measurements at several other masses.

Phase Separation of P3HT/PMMA Blend Film for Forming Semiconducting and Dielectric Layers in Organic Thin-Film Transistors for High-Sensitivity NO2 Detection

Formation of the semiconductor/dielectric double-layered films via vertical phase separations from polymer blends is an effective method to fabricate organic thin-film transistors (OTFTs). Here, we introduce a simple one-step processing method for the vertical phase separation of poly(3-hexylthiophene-2,5-diyl) (P3HT) and poly(methyl methacrylate) (PMMA) blends in OTFTs and their applications for high-performance nitrogen dioxide (NO₂) sensors. Compared to the conventional two-step coated OTFT sensors, one-step processed devices exhibit a great enhancement of the responsivity from 116 to 1481% for 30 ppm NO₂ concentration and a limit of detection of ∼0.7 ppb. Studies of the microstructures of the blend films and the electrical properties of the sensors reveal that the devices formed by the one-step vertical phase separation have better capability for the adsorption of NO₂ molecules. Moreover, a careful adjustment of the blend ratio between P3HT and PMMA can further improve the performance of the NO₂ sensors, ranging from sensitivity to selectivity and to the ability of recovery. This simple one-step processing method demonstrates a potential possibility for developing high-performance, low-cost, and large-area OTFT gas sensors.

MR-based cardiac and respiratory motion correction of PET: application to static and dynamic cardiac 18F-FDG imaging

Motion of the myocardium deteriorates the quality and quantitative accuracy of cardiac PET images. We present a method for MR-based cardiac and respiratory motion correction of cardiac PET data and evaluate its impact on estimation of activity and kinetic parameters in human subjects. Three healthy subjects underwent simultaneous dynamic ¹⁸F-FDG PET and MRI on a hybrid PET/MR scanner. A cardiorespiratory motion field was determined for each subject using navigator, tagging and golden-angle radial MR acquisitions. Acquired coincidence events were binned into cardiac and respiratory phases using electrocardiogram and list mode-driven signals, respectively. Dynamic PET images were reconstructed with MR-based motion correction (MC) and without motion correction (NMC). Parametric images of ¹⁸F-FDG consumption rates (K_i) were estimated using Patlak's method for both MC and NMC images. MC alleviated motion artifacts in PET images, resulting in improved spatial resolution, improved recovery of activity in the myocardium wall and reduced spillover from the myocardium to the left ventricle cavity. Significantly higher myocardium contrast-to-noise ratio and lower apparent wall thickness were obtained in MC versus NMC images. Likewise, parametric images of K_i calculated with MC data had improved spatial resolution as compared to those obtained with NMC. Consistent with an increase in reconstructed activity concentration in the frames used during kinetic analyses, MC led to the estimation of higher K_i values almost everywhere in the myocardium, with up to 18% increase (mean across subjects) in the septum as compared to NMC. This study shows that MR-based motion correction of cardiac PET results in improved image quality that can benefit both static and dynamic studies.

[Study on the relationship between smoking behavior and health literacy among grade 4-6 primary students in Shandong province]

Objective: To investigate the associations between smoking and literacy on health among 4-6 grade primary school students. Methods: A questionnaire survey was conducted to research on health literacy and smoking among 4-6 grade pupils in Shandong province, through a multi-stage stratified cluster random sampling method. Sociodemographic characteristics, health literacy level and smoking rate were collected from respondents. Binary logistic regression analysis was used to evaluate the association of smoking and health literacy. Results: A total of 9 240 questionnaires were distributed, with the rate of valid response as 99.7%. The current smoking rate of the students was 2.6%, on higher in boys (3.1%) than in girls (2.0%). 60.8% of 4-6 grade students were found to have adequate health literacy level. Levels of literacy health in both boy and girl school students appeared 56.7% and 64.9%, respectively. Results indicated that health literacy in smokers (14.4%) was lower than that in non-smokers (62.0%). Results from the binary logistic regression analysis showed that the independent influencing factors would include grade, father's education level, economic situation of the family, self-assessment on the school record and literacy on health (P<0.01). After controlling the other independent variables, the smoking rate was 8.62 (1/0.116) times in students with low literacy level on health, than those with high literacy level. Conclusions: Literacy on health was significantly associated with smoking in the 4-6 grade pupils of Shandong province.

THERMOLUMINESCENCE OF NEWLY DEVELOPED HIGHLY SENSITIVE α-Al2O3:C BY THE VERTICAL GRADIENT FREEZING METHOD

A highly sensitive α-Al2O3:C crystal was directly grown by the vertical gradient freezing (VGF) method using Al2O3 and graphite powder as the raw materials. The main thermoluminescence (TL) characteristics of α-Al2O3:C detectors grown by the VGF method and TLD-500K detectors were compared. The α-Al2O3:C grown by the VGF method shows good dosimetric properties, such as high TL sensitivity (152 times higher than that of the TLD-100 at heating rate of 1°C/s), an extremely low residual signal of 0.03%, a minimum measurable dose of 0.12 μGy and an excellent linear response within the dose range studied from 1 μGy to 10 Gy. The α-Al2O3:C detectors grown by the VGF method have a higher sensitivity and a better linear response compared to the TLD-500K detectors. Both kinds of α-Al2O3:C can be used in an unannealed form and to measure the very low dose in environmental monitoring and personnel dosimetry.

Blood Flow Regulates Zebrafish Caudal Vein Plexus Angiogenesis by ERK5-klf2a-nos2b Signaling

BACKGROUND

Vascular network formation induced by angiogenesis plays an important role in many physiological and pathological processes. However, the role of blood flow and underlying mechanisms in vascular network formation, for example for the development of the caudal vein plexus (CVP), is poorly understood.

OBJECTIVE

The aim of this study was to explore the role of ERK5-klf2a-nos2b signaling in the CVP angiogenesis.

METHOD AND RESULTS

In this study on tnnt2a-MO injection and chemical blood flow modulator treatment in zebrafish embryos, we demonstrated that decreased blood flow disrupted CVP formation. The hemodynamic force was quantitatively analyzed. Furthermore, CVP angiogenesis in zebrafish embryos was inhibited by disruption of the blood flow downstream effectors ERK5, klf2a, and nos2b in response to treatment with the ERK5 specific inhibitor and to injection of klf2a-MO, nos2b-MO. Overexpression of klf2a mRNA or nos2b mRNA restored vascular defects in tnnt2a or klf2a morphants. The data suggest that flow-induced ERK5-klf2a-nos2b signaling is involved in CVP angiogenesis in zebrafish embryos.

CONCLUSION

We have demonstrated that blood flow is essential for vascular network formation, specifically for CVP angiogenesis in zebrafish. A novel genetic and mechanical mechanism was discovered in which ERK5 facilitates the integration of blood flow with the downstream klf2a-nos2b signaling for CVP angiogenesis.

Mechanisms regulating radiosensitivity of glioma stem cells

Malignant glioblastoma (GBM) has become a very common and difficult brain tumor given its low cure rate and high recurrence rate. GBMs are resistant to treatments because glioma stem cells (GSCs)/glioma-initiating cells (GICs), a specific subpopulation of GBM, possess properties of tumor stem cells, such as unlimited proficiency, self-renewal, differentiation and resistance to chemotherapy and radiotherapy, and exhibit a very strong DNA repair capability. Radiotherapy has become a preponderant treatment, and researchers have found many significant tumor microenvironmental factors and valuable signaling pathways regulating the GSC radioresistance, including NOTCH, Wnt/β-catenin, Hedgehog, STAT3, and PI3K/AKT/mTOR. Therefore, we seek to boost GSC radiosensitivity through activating or inactivating pathways alone or together to eliminate the likely source of glioma and prolong survival of patients.

[Task-related functional connectivity of anterior cingutate in opiate drug addicts during physical detoxification: a task fMRI study]

Objective: To explore the brain areas which have abnormal functional connectivity with anterior cingutate in opiate drug dependence during physical detoxification using a task-related functional magnetic resonance imaging(fMRI), and to find out the role of anterior cingutate dysfunction in the relapse of opiate drug addicts during physical detoxification. Methods: From January to December 2016, eighteen participants of opiate drug addicts during physical detoxification who completed in Drug Rehabilitation Center of Anhui Province, and eighteen healthy controls recruited performed a cue-elicited craving task in a MRI scanner while signal data were collected. Two regions of interest were the right anterior cingutate and the left anterior cingutate, then the linear correlation between the whole brain and the anterior cingutates was calculated to find out the abnormal functional connectivity of the anterior cingutates. Results: Contrasted experimental group with the healthy controls, the functional connectivity of bilateral fusiform gyrus, caudate nucleus, and the anterior cingutates was increased in the opiate drug addicts during physical detoxification group (P<0.05),and the functional connectivity between anterior cingutates and polus temporalis, hippocampi, Middle frontal gyrus of orbit, Supplementary motor area, dorsolateral superior frontal gyrus was decreased(P<0.05). Conclusion: The anterior cingutates dysfunction of functional connectivity in a cue-elicited craving task may play a important role in the relapse of opiate drug addicts during physical detoxification.

[The value of platelet count in predicting the efficacy of rituximab treatment in adult patients with chronic primary immune thrombocytopenia]

目的

探讨血小板计数水平在成人慢性原发免疫性血小板减少症（ITP）患者利妥昔单抗疗效预测中的价值。

方法

回顾性分析2011年1月1日至2014年12月31日期间接受利妥昔单抗治疗（100 mg每周1次，连用4次）慢性ITP患者的临床资料，计算利妥昔单抗治疗后不同随访时间截点血小板计数预测疗效的敏感性、特异性和阳性预测值、阴性预测值，并通过ROC曲线下面积得出最佳截断点。

结果

103例患者纳入研究，男46例，女57例，中位年龄30（18~67）岁。首剂利妥昔单抗后第1、5、7天，成功组（治疗后PLT≥50×10⁹/L且未接受其他药物治疗）与无效组（治疗后PLT<50×10⁹/L）中位血小板计数差异均无统计学意义（P>0.05）；利妥昔单抗治疗后第14天，成功组中位血小板计数高于无效组[41（8~384）×10⁹/L对23（0~106）×10⁹/L，P=0.003]；在随后的各随访截点，成功组中位血小板计数进一步回升并维持于正常水平，无效组中位血小板计数均低于正常水平。以ROC曲线获得的预测治疗反应的优化界限值血小板计数50×10⁹/L为基础，首剂妥昔单抗治疗后第14、30、60天血小板计数能够组成一个预后评估体系。

结论

利妥昔单抗治疗后第14、30、60天血小板计数能够组成一个疗效预测评估体系，有助于随访和制定治疗计划。

Abstract P5-11-08: Genetic landscape of prior and resistance to CDK4/6 inhibition in targeted NGS panel analysis of palbociclib or abemaciclib and endocrine versus placebo and endocrine

Background: CDK4/6 inhibition combined with endocrine therapy is now a standard of care for advanced estrogen receptor (ER) positive breast cancer. Predictive genetic landscape and mechanisms of resistance to CDK4/6 inhibitors have not been described clearly because of limited evidence from clinical samples. We investigated the genetic landscape and mechanisms of resistance to CDK4/6 inhibitors (palbociclib or abemaciclib).

Methods: Using driver mutation targeted sequencing, we conducted longitudinal ctDNA analysis in 39 pairs of baseline of primary tumor and end of treatment or monitoring plasma samples. DNA were extracted and the genomic profiles were analyzed based on NGS.

Results: In our cohort, the most frequence mutations were PIK3CA (38.5%), TP53(17.9%), CCND1, ZNF703, FGFR1, MAP2K4, RB1, ARID1A, ATRX, DNMT3A. In five paitents harboring RB1 mutations prior to CDK4/6 inhibitor, only one case occured progressing early with 4mos of PFS, and the others were 5.5+, 6.5+, 13.5+, 21+months, it represented different from pre-clinical results that RB1 mutation was associated with resistance to CDK4/6 inhibitor. Interesting, patients with PIK3CA/PTEN/AKT1 mutations (n=15) were likely sensitivity to CDK4/6 inhibitor than those (n=11) with wild type (median PFS: 17 mos vs. 9.5mos, P=0.046). In another cohort of everolimus, new driver mutations emerged in both FGFR1 and ERBB3 at end of everolimus and significantly disappeared in AKT1 mutation. Three patients used palbociclib after progress disease of everolimus, the prognosis were poor with PFS of 1, 6, 9 mos. Evolution of driver gene mutations was uncommon in patients progressing on CDK4/6 inhibitors treatment, but common in patients progressing on everolimus treatment.

Conclusions: De novo PIK3CA/PTEN/AKT1 mutations were likely better prognosis biomarkers with the treatment of CDK4/6 inhibitor. RB1 mutation are common and may not contribute to CDK4/6 inhibitor resistance differ from PALOMA3 ctDNA analysis. Our small sample finding indicate it may be a bad stragegy for CDK4/6 inhibitor after progress disease with mTOR inhibitor everolimus.

Citation Format: Xu J, Sun T, Wang X. Genetic landscape of prior and resistance to CDK4/6 inhibition in targeted NGS panel analysis of palbociclib or abemaciclib and endocrine versus placebo and endocrine [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-11-08.

Mechanically Excited Multicolor Luminescence in Lanthanide Ions

Mechanoluminescence (ML) featuring photon emission by mechanical stimuli is promising for applications such as stress sensing, display, and artificial skin. However, the progress of utilizing ML processes is constrained by the limited range of available ML emission spectra. Herein, a general strategy for expanding the emission of ML through the use of lanthanide emitters is reported. A lithium-assisted annealing method for effective incorporation of various lanthanide ions (e.g., Tb³⁺ , Eu³⁺ , Pr³⁺ , Sm³⁺ , Er³⁺ , Dy³⁺ , Ho³⁺ , Nd³⁺ , Tm³⁺ , and Yb³⁺ ) into CaZnOS crystals that are identified as one of the most efficient host materials for ML is developed. These doped CaZnOS crystals show efficient and tunable ML spanning full spectrum from violet to near infrared. The multicolor ML materials are used to create encrypted anticounterfeiting patterns, which produce spatially resolvable optical codes under single-point dynamic pressure of a ballpoint pen.

Efficacy and safety of combined androgen blockade with antiandrogen for advanced prostate cancer

Background

Combined androgen blockade (cab) is a promising treatment modality for prostate cancer (pca). In the present meta-analysis, we compared the efficacy and safety of first-line cab using an antiandrogen (aa) with castration monotherapy in patients with advanced pca.

Methods

PubMed, embase, Cochrane, and Google Scholar were searched for randomized controlled trials (rcts) published through 12 December 2016. Hazard ratios (hrs) with 95% confidence intervals (cis) were determined for primary outcomes: overall survival (os) and progression-free survival (pfs). Subgroup analyses were performed for Western compared with Eastern patients and use of a nonsteroidal aa (nsaa) compared with a steroidal aa (saa).

Results

Compared with castration monotherapy, cab using an aa was associated with significantly improved os (n = 14; hr: 0.90; 95% ci: 0.84 to 0.97; p = 0.003) and pfs (n = 13; hr: 0.89; 95% ci: 0.80 to 1.00; p = 0.04). No significant difference in os (p = 0.71) and pfs (p = 0.49) was observed between the Western and Eastern patients. Compared with castration monotherapy, cab using a nsaa was associated with significantly improved os (hr: 0.88; 95% ci: 0.82 to 0.95; p = 0.0009) and pfs (hr: 0.85; 95% ci: 0.73 to 0.98; p = 0.007)-a result that was not achieved with cab using a saa. The safety profiles of cab and monotherapy were similar in terms of adverse events, including hot flushes, impotence, and grade 3 or 4 events, with the exception of risk of diarrhea and liver dysfunction or elevation in liver enzymes, which were statistically greater with cab using an aa.

Conclusions

Compared with castration monotherapy, first-line cab therapy with an aa, especially a nsaa, resulted in significantly improved os and pfs, and had an acceptable safety profile in patients with advanced pca.

[Comparison of the accuracy of neuronavigation and linear measurement in the positioning of parasagittal meningioma]

Objective: To explore the accuracy of preoperative positioning of neuronavigation and linear measurement localization in the parasagittal meningioma. Methods: Thirty-eight patients with parasagittal meningioma who underwent neurosurgery in the First Affiliated Hospital of Bengbu Medical College from January 2016 to April 2018 were preoperatively positioned with neuronavigation localization and linear measurement localization. The actual position of the tumor was observed during operation, and the accuracy of the two methods was compared. The time taken by the neural navigation positioning and the linear measurement positioning method was recorded, and the difference between the two methods was compared. Results: All cases were treated with neuronavigation and linear measurement, and the tumors were completely exposed after localization. Compared with the actual tumor center position measured during surgery, the average error distance between 38 nerve navigation and actual tumor center position was (2.7±1.9) mm, and the average error distance between linear measurement and actual tumor center position was (3.2±1.3) mm. The difference was not statistically significant, P value=0.207. Neuronavigation includes booting, data import, registration, positioning, etc., which takes an average of (22.3±2.3) minutes. The linear positioning method included image data measurement and localization, and the average time was(1.7±0.3) minutes. The difference between the two groups was statistically significant, and the P value was less than 0.001. Conclusion: The linear measurement localization method and the neuronavigation localization method have good accuracy for preoperative localization of the parasagittal meningioma.

[Efficacy and mechanism of loading dose clopidogrel in patients with transient ischemic attack and minor stroke]

Objective: To assess outcome, safety and possible mechanism of loading dose clopidogrel in patients with transient ischemic attack (TIA) and minor stroke. Methods: We reviewed patients with confirmed TIA and minor stroke admitted between July 2016 and December 2017 into the First Affiliated Hospital of Soochow University. Loss-of-function allele carriers of CYP2C19 were included and randomly divided into loading dose group (first dose of 300 mg clopidogrel) and standard dose group (first dose of 75 mg clopidogrel), 100 mg aspirin was gave at the same time, followed by aspirin 100 mg/d plus clopidogrel 75 mg/d maintaining for 20 days. Platelet aggregation (maximum aggregation ratio, MAR) induced by Adenosine diphosphate (ADP) was examined before and 3 days after administration. The National Institutes of Health Stroke Scale (NIHSS) score method was employed to assess the NIHSS scores before and after treatment in each group of patients; the modified Rankin Scale (mRS) was used to assess the 3-month functional outcome. Results: There was no significant difference in baseline data between the two groups (P>0.05).The proportion of early neurological function improvement in the two groups was 75.0% and 54.8%, and the difference was statistically significant (χ(2)=4.498, P=0.034). The 3-month prognosis was 79.5% and 61.3%, and the difference was statistically significant (χ(2)=4.000, P=0.045). Adverse events: 1 case in the loading dose group, 1 case in the standard dose group, the difference was not statistically significant (2.3% vs 1.6%, χ(2)=0.061, P=0.806). After 3 days of antiplatelet therapy, the MAR of the loading dose group decreased (11%±8%), and the MAR of the standard dose group decreased (9%±4%), the difference was statistically significant (P=0.013).In the loading dose group, there were 32 (72.7%)CYP2C19*2 carriers and 42 (95.5%)CYP2C19*2+*3 carriers; early neurological function improvement in 33 cases, accounting for 93.8% and 76.2%, respectively, and the difference was statistically significant (χ(2)=4.122, P=0.042). There were 35 patients with good prognosis in 3 months, accounting for 96.9% and 81.0%, respectively. The difference was statistically significant (χ(2)=4.310, P=0.038); MAR of CYP2C19*2 carrier was decreased (15%±5%), and MAR of CYP2C19*2+*3 carrier was decreased (12%±8%). The difference was statistically significant (P=0.039). Conclusions: Loading dose clopidogrel can improve the clinical prognosis of minor stroke/TIA without increasing the risk of bleeding. Loading dose clopidogrel may improve the prognosis of minor stroke/TIA by decreasing MAR of CYP2C19*2 carriers.

[Application of modified brain protection double-lumen drainage tube in external drainage of chronic subdural hematoma]

Objective: To compare the clinical effects of modified double-lumen drainage tube and traditional silicone tube in external drainage of chronic subdural hematoma. Methods: Selected 49 patients suffering from chronic subdural hematoma hospitalized in the Department of Neurosurgery, the First Affiliated Hospital of Bengbu Medical College between July 2016 and June 2018 who underwent external drainage, and divided them randomly into experimental groups (using modified brain protection double lumen drainage tube in 23 cases) and control group (using traditional silicone drainage tube in 26 cases). Comparison of postoperative hematoma residual volume, the tube indwelling time, the numbers of drainage tube contact with brain tissue and arachnoid membrane, the numbers of infections, the numbers of postoperative epilepsy cases, and changes in Modified Rankin Scale scores between the two groups. Results: At the time of extubation, the residual amount of hematoma in the experimental group was (13±7) ml, and that in the control group was (17±8) ml. There was no significantly statistical difference in the residual amount of hematoma between the experimental group and the control group (P>0.05). The tube indwelling time of the experimental group was (2.0±0.9) days, and that of the control group was (2.7±0.8) days. The difference between the experimental group and the control group in the drainage tube indwelling time was statistically significant (P<0.05). No cases of drainage tube contact with brain tissue and/or arachnoid membrane appeared in the experimental group, and 7 cases of drainage tube contact with brain tissue or arachnoid membrane appeared in the control group. No infection occurred in both groups. No cases of epilepsy occurred in preoperative, and there were 0 cases of epilepsy in the experimental group and 1 case in the control group in postoperative. There were significantly statistical differences in each of the two groups in the modified Rankin scale before and after surgery (P<0.001), there was no significant difference in postoperative Modified Rankin Scale scores between the two groups. Conclusion: The modified brain protection double-lumen drainage tube has good drainage effect in the external drainage of chronic subdural hematoma, and the short tube retention time, causing fewer complications. It is a safe and effective tool for treating chronic subdural hematoma, and it is worthy of clinical promotion.

[The anti-cancer effect of ZR30 protein via targeting extracellular signal proteins of different cell subpopulations of glioma]

Objective: To investigate the roles and anti-cancer mechanism of artificially synthesized EGF-containing fibulin-like extracellular matrix protein (EFEMP1) derived tumor suppressor ZR30 protein in glioma (GBM). Methods: ZR30 protein were in vitro expressed using a wheat germ cell-free system. GBM cell lines (U251, U251NS, and U87) were cultured for 2-3 days in the presence or absence of ZR30 treatment. MMP-2 level was detected by gelatin zymography assay, moreover, the expression of EGFR, Notch-1 and p-Akt/Akt levels were determined by western blot. Additionally, MTT assay was used to measure ZR30's effect on the cell proliferation of U251 and U251NS cells. Furthermore, pre-mixed U251-GFP and U251NS-RFP cells (1∶9) were injected into the brain of nude mice, and then ZR30 or PBS was injected into the intra-tumor after 10 and 21 days, respectively. Then DNA was extracted from the right brain of nude mice in each group. Comparative quantitative polymerase chain reaction (CQ-PCR) was used to examine the copy numbers of human gene hSPAG16, mouse gene mSpag16, GFP and RFP. The survival status of each group of nude mice was also observed. Results: The levels of activated MMP-2 in U87 and U251 cells were lower after 10, 50 and 100 ng/ml ZR30 treatment for 2-3 days. Western blot analysis showed that ZR30 treatment reduced the expression of EGFR, Notch-1 and p-Akt/Akt in U251 cells, and inhibited Notch-1 and p-Akt/Akt expression in U251NS cells, and then decreased the response of U251 cells to EGF stimulation. Moreover, ZR30 inhibited the cell proliferation of U251 and U251NS two days after exposure. The in vivo orthotopic GBM xenografts were successfully constructed. CQ-PCR results indicated that the hSPAG16/mSpag16 ratios of mice in PBS group and ZR30 treatment groups at 180, 700, and 1 800 ng dosages were 3.67±2.82, 1.18±0.97, 1.75±1.55 and 1.38±1.17, respectively, and ZR30 treatment groups showed significantly lower ratios than the PBS group (P<0.05 for all). Correspondingly, the ratios of GFP/RFP in each group were 1.97±0.80, 1.97±0.85, 1.48±0.71 and 1.73±0.77, respectively, showing no statistical significance (P>0.05 for all). When treatment was performed 10 d after cell implantation, and the median survival time of mice in PBS group and ZR30 group was 40.5 days and 59.0 days, respectively. When treatment was performed 21 d after cell implantation, the median survival time of mice in PBS group and ZR30 group was extended to 57.0 days and 74.5 days, respectively. The median survival time of ZR30 treatment groups significantly prolonged (P<0.05 for all). Conclusions: ZR30 inhibits in vitro cell growth, invasion, angiogenesis and stemness maintenance in glioma via suppressing activated MMP-2, EGFR, p-Akt/Akt and Notch-1 proteins. In vivo, ZR30 markedly increased survival of mice harboring glioma xenografts, even for only one intra-tumoral injection at the time of early tumor formation. Overall, the in vivo and in vitro experiments supported the therapeutic potential of ZR30 for GBM.

[Comparation study of incidental irradiation dose to the internal mammary chain during postmastectomy radiotherapy for patients treated with different irradiation techniques]

Objective: To evaluated the unplanned coverage dose to the internal mammary chain (IMC) in patient treated with postmastectomy radiotherapy (PMRT). Methods: One hundred and thirty eight patients with breast cancer receiving radiotherapy (RT) in our hospital were retrospectively analyzed. Patients were divided into three groups: three-dimensional conformal radiotherapy (3D-CRT) group, forward intensity-modulated radiotherapy (F-IMRT) group and inverse IMRT (I-IMRT) group. The IMC were contoured according to Radiation Therapy Oncology Group (RTOG) consensus, and were not include into the planning target volume (PTV). The incidental irradiation dose to IMC among the three groups and the first three intercostal spaces IMC (ICS-IMC 1-3) were all compared, and explored the relationship between the mean doses (Dmean) of IMC and the OARs (ipsilateral lung and heart). Results: The dose delivered to IMC showed no difference in CRT, F-IMRT and I-IMRT(33.80 Gy, 29.65 Gy and 32.95 Gy). And 10.42%, 2.04%, and 9.76% patients achieved ≥45 Gy when treated with CRT, F-IMRT and I-IMRT. For the IMC dose in the first three intercostal spaces (ICS1-3), there was no difference to the three treatment plannings. The Dmean, V(20), V(30), V(40) and V(50) of the ICS-IMC2 and ICS-IMC3 were all obviously superior than ICS-IMC1 for all these three plannings. Moderate positive correlation was founded between Dmean for IMC and Dmean for heart for left breast cancer patients underwent CRT (r=0.338, P=0.01). Whereas for F-IMRT and I-IMRT groups, positive correlation were founded between Dmean for IMC and Dmean and V(20) for ipsilateral lung for all patients (F-IMRT: r=0.366, P=0.010; r=0.318, P=0.026; I-IMRT: r=0.427, P=0.005; r=0.411, P=0.008). Conclusions: In 3D-CRT, F-IMRT and I-IMRT planning methods, partial patients get IMC irradiated doses that could achieve therapeutic doses. Compared with 3D-CRT, F-IMRT and I-IMRT further reduced the dose of irradiated organs. However, there is no difference in the dose coverage of IMC for the three planned approaches when the IMC made an unplanned target.

Pulsed electromagnetic fields preserve bone architecture and mechanical properties and stimulate porous implant osseointegration by promoting bone anabolism in type 1 diabetic rabbits

The effects of exogenous pulsed electromagnetic field (PEMF) stimulation on T1DM-associated osteopathy were investigated in alloxan-treated rabbits. We found that PEMF improved bone architecture, mechanical properties, and porous titanium (pTi) osseointegration by promoting bone anabolism through a canonical Wnt/β-catenin signaling-associated mechanism, and revealed the clinical potential of PEMF stimulation for the treatment of T1DM-associated bone complications.

INTRODUCTION

Type 1 diabetes mellitus (T1DM) is associated with deteriorated bone architecture and impaired osseous healing potential; nonetheless, effective methods for resisting T1DM-associated osteopenia/osteoporosis and promoting bone defect/fracture healing are still lacking. PEMF, as a safe and noninvasive method, have proven to be effective for promoting osteogenesis, whereas the potential effects of PEMF on T1DM osteopathy remain poorly understood.

METHODS

We herein investigated the effects of PEMF stimulation on bone architecture, mechanical properties, bone turnover, and its potential molecular mechanisms in alloxan-treated diabetic rabbits. We also developed novel nontoxic Ti2448 pTi implants with closer elastic modulus with natural bone and investigated the impacts of PEMF on pTi osseointegration for T1DM bone-defect repair.

RESULTS

The deteriorations of cancellous and cortical bone architecture and tissue-level mechanical strength were attenuated by 8-week PEMF stimulation. PEMF also promoted osseointegration and stimulated more adequate bone ingrowths into the pore spaces of pTi in T1DM long-bone defects. Moreover, T1DM-associated reduction of bone formation was significantly attenuated by PEMF, whereas PEMF exerted no impacts on bone resorption. We also found PEMF-induced activation of osteoblastogenesis-related Wnt/β-catenin signaling in T1DM skeletons, but PEMF did not alter osteoclastogenesis-associated RANKL/RANK signaling gene expression.

CONCLUSION

We reveal that PEMF improved bone architecture, mechanical properties, and pTi osseointegration by promoting bone anabolism through a canonical Wnt/β-catenin signaling-associated mechanism. This study enriches our basic knowledge for understanding skeletal sensitivity in response to external electromagnetic signals, and also opens new treatment alternatives for T1DM-associated osteopenia/osteoporosis and osseous defects in an easy and highly efficient manner.

[Microsurgical treatment of temporal cavernous malformation presenting with epilepsy]

Objective: To evaluate the efficacy and safety of microsurgical in the treatment of temporal lobe cerebral cavernous malformation (CCM) with epilepsy. Methods: Temporal lobe CCM patients with epilepsy admitted to our department were collected from January 2010 to September 2016. Locations of the CCM were divided into (1) lateral-lateral to the collateral sulcus; (2) mesial-mesial to the collateral sulcus. In the lateral group, patients were underwent intraoperative electrocorticography (ECoG)-guided resection of lesion and hemosiderin rim. In the medial group, a complete resection of the epileptogenic zone was performed in anterior temporal lobe and hippocampus and (or) amygdala according to lesion and hemosiderin rim. The follow-up period in all patients was at least 1 year. The outcome of epilepsy treatment was evaluated according to the standard Engel scale. Results: Eight patients belong to the lateral group, including 2 males and 6 females, mean age at epilepsy surgery was 35 years old, 100% of patients achieved Engel class Ⅰ the last follow up. The mesial group had 7 patients, including 4 males and 3 females, mean age at epilepsy surgery was 52 years old, 71.8% of the patients were Engel Class Ⅰ, 14% were Class Ⅱ, and 14% were Class Ⅲ. The patient who was Engel Class Ⅲ had a posterior temporal venous infarction due to injured the developmental venous anomalies (DVAs). Conclusions: CCM Patients with epilepsy could benefit greatly from complete resection of hemosiderin rim and lesion. The epilepsy prognosis were closely correlated with the location of CCM. Further research is necessary to determine therapeutic strategies of CCMs with associated DVAs.

Changes in nitric oxide levels and their relationship with callose deposition during the interaction between soybean and Soybean mosaic virus

The present study aimed to investigate changes in nitric oxide (NO) level and its relationship with callose deposition during the interaction between soybean and Soybean mosaic virus (SMV). Soybean cv. 'Jidou 7' and SMV strains N3 and SC-8 were used to constitute incompatible and compatible combinations. Intracellular NO was labelled with the NO-specific fluorescence probe DAF-FM DA. Confocal laser scanning microscopy (CLSM) was then used to observe changes in NO production during SMV infection-induced defence responses in soybean. The results showed NO fluorescence increased rapidly at 2-72 h post-inoculation, peaked at 72 h and then decreased in the incompatible combination. However, in the compatible combination, extremely weak NO fluorescence appeared in the early stage (2-24 h) post-inoculation, but was not observed thereafter. Injections of the NO scavenger c-PTIO prior to inoculation postponed the onset of NO production to 48 or 72 h post-inoculation. The same occurred when injections of NR or NOS inhibitors were applied prior to inoculation. The observation of callose fluorescence in the incompatible combination revealed that either the elimination or reduction of NO in the early stage led to a delay in callose formation, enabling the virus to cause systemic infection. Together with our previous findings, this study indicates that viral infection could induce NO production and callose deposition during the incompatible interaction between soybean and SMV. The production of NO involves NR and NOS enzymatic pathways, and NO mediates the process of callose deposition at plasmodesmata.

An upconversion nanoplatform with extracellular pH-driven tumor-targeting ability for improved photodynamic therapy

Upconversion nanoparticles (UCNPs) are widely utilized for photodynamic therapy (PDT) due to their specific upconverting luminescence that utilizes near infrared (NIR) light to excite photosensitizers (PSs) for PDT. The efficiency of UCNP-based PDT will be improved if the cancer-targeting property of nanomedicine is enhanced. Herein, we employed the pH low insertion peptide (pHLIP), a cancer-targeting moiety, to functionalize an 808 nm excited UCNP-based nanoplatform that has a minimized over-heating effect to perform PDT. pHLIP can bring cargo specifically into cancer cells under an acidic environment, realizing the effective active-targeting abilities to cancer cells or tumor due to acidosis. The pHLIP-functionalized nanoplatform was assembled and well characterized. The nanoplatform shows an efficient NIR-irradiated PDT effect in cancer cells, especially under a slightly acidic condition that mimics the tumor microenvironment, and this effectiveness is attributed to the targeting properties of pHLIP to cancer cells under acidic conditions that favor the entry of the nanoplatform. Furthermore, the pHLIP-functionalized nanoplatform shows a favorable safety profile in mice with a high maximum tolerated dose (MTD), which may broaden the availability of administration in vivo. The efficient in vivo antitumor activity is achieved through intratumor injection of the nanoplatform followed by NIR irradiation on the breast tumor. The nanoparticles are largely accumulated in the tumor site, revealing the excellent tumor-targeting properties of the pHLIP-functionalized nanoplatform, which ensures efficient PDT in vivo. Moreover, the nanoparticles have a long retention time in the bloodstream, indicating their stability in vivo. Overall, we provide an example of a UCNP-based nanosystem with tumor-targeting properties to perform efficient PDT both in vitro and in vivo.

Yb3+-sensitized upconversion and downshifting luminescence in Nd3+ ions through energy migration

A core-shell-shell nanostructure composed of NaGdF₄:Yb/Tm@NaGdF₄:Nd@NaYF₄ is developed to realize Yb³⁺-sensitized upconversion and downshifting luminescence in Nd³⁺ ions. The unusual photon conversion property stems from a gadolinium sublattice mediated Yb³⁺→ Tm³⁺→ Gd³⁺→ Nd³⁺ energy transfer pathway. The energy transfer processes are investigated by varying the dopant concentration and distribution, in conjunction with time decay measurements.

Core-Shell-Shell Upconversion Nanoparticles with Enhanced Emission for Wireless Optogenetic Inhibition

Recent advances in upconversion technology have enabled optogenetic neural stimulation using remotely applied optical signals, but limited success has been demonstrated for neural inhibition by using this method, primarily due to the much higher optical power and more red-shifted excitation spectrum that are required to work with the appropriate inhibitory opsin proteins. To overcome these limitations, core-shell-shell upconversion nanoparticles (UCNPs) with a hexagonal phase are synthesized to optimize the doping contents of ytterbium ions (Yb³⁺) and to mitigate Yb-associated concentration quenching. Such UCNPs' emission contains an almost three-fold enhanced peak around 540-570 nm, matching the excitation spectrum of a commonly used inhibitory opsin protein, halorhodopsin. The enhanced UCNPs are utilized as optical transducers to develop a fully implantable upconversion-based device for in vivo tetherless optogenetic inhibition, which is actuated by near-infrared (NIR) light irradiation without any electronics. When the device is implanted into targeted sites deep in the rat brain, the electrical activity of the neurons is reliably inhibited with NIR irradiation and restores to normal level upon switching off the NIR light. The system is further used to perform tetherless unilateral inhibition of the secondary motor cortex in behaving mice, achieving control of their motor functions. This study provides an important and useful supplement to the upconversion-based optogenetic toolset, which is beneficial for both basic and translational neuroscience investigations.

An upconversion nanoplatform for simultaneous photodynamic therapy and Pt chemotherapy to combat cisplatin resistance

Platinum-based antineoplastic drugs are among the first-line chemotherapeutic agents against a variety of solid tumors, but toxic side-effects and drug resistance issues limit their clinical optimization. Novel strategies and platforms to conquer cisplatin resistance are highly desired. Herein, we assembled a multimodal nanoplatform utilizing 808 nm-excited and biocompatible core-shell-shell upconversion nanoparticles (UCNPs) [NaGdF4:Yb/Nd@NaGdF4:Yb/Er@NaGdF4] that were covalently loaded with not only photosensitizers (PSs), but also Pt(iv) prodrugs, which were rose bengal (RB) and c,c,t-[Pt(NH3)2Cl2(OCOCH2CH2NH2)2], respectively. The UCNPs had the capability to convert near infrared (NIR) light to visible light, which was further utilized by RB to generate singlet oxygen. At the same time, the nanoplatform delivered the Pt(iv) prodrug into cancer cells. Thus, this upconversion nanoplatform was able to carry out combined and simultaneous photodynamic therapy (PDT) and Pt chemotherapy. The nanoplatform was well characterized and the energy transfer efficiency was confirmed. Compared with free cisplatin or UCNPs loaded with RB only, our nanoplatform showed significantly improved cytotoxicity upon 808 nm irradiation in both cisplatin-sensitive and -resistant human ovarian cancer cells. A mechanistic study showed that the nanoparticles efficiently delivered the Pt(iv) prodrug into cancer cells, resulting in Pt-DNA damage, and that the nanoplatform generated cellular singlet oxygen to kill cancer cells. We, therefore, provide a comprehensive strategy to use UCNPs for combined Pt chemotherapy and PDT against cisplatin resistance, and our nanoplatform can also be used as a theranostic tool due to its NIR bioimaging capacity.

Structural responses of metallic glasses under neutron irradiation

Seeking nuclear materials that possess a high resistance to particle irradiation damage is a long-standing issue. Permanent defects, induced by irradiation, are primary structural changes, the accumulation of which will lead to structural damage and performance degradation in crystalline materials served in nuclear plants. In this work, structural responses of neutron irradiation in metallic glasses (MGs) have been investigated by making a series of experimental measurements, coupled with simulations in ZrCu amorphous alloys. It is found that, compared with crystalline alloys, MGs have some specific structural responses to neutron irradiation. Although neutron irradiation can induce transient vacancy-like defects in MGs, they are fully annihilated after structural relaxation by rearrangement of free volumes. In addition, the rearrangement of free volumes depends strongly on constituent elements. In particular, the change in free volumes occurs around the Zr atoms, rather than the Cu centers. This implies that there is a feasible strategy for identifying glassy materials with high structural stability against neutron irradiation by tailoring the microstructures, the systems, or the compositions in alloys. This work will shed light on the development of materials with high irradiation resistance.

Effects of bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) release from polylactide-poly (ethylene glycol)-polylactide (PELA) microcapsule-based scaffolds on bone

Multiple growth factors can be administered to mimic the natural process of bone healing in bone tissue engineering. We investigated the effects of sequential release of bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) from polylactide-poly (ethylene glycol)-polylactide (PELA) microcapsule-based scaffolds on bone regeneration. To improve the double emulsion/solvent evaporation technique, VEGF was encapsulated in PELA microcapsules, to which BMP-2 was attached. The scaffold (BMP-2/PELA/VEGF) was then fused to these microcapsules using the dichloromethane vapor method. The bioactivity of the released BMP-2 and VEGF was then quantified in rat mesenchymal stem cells (rMSCs). Immunoblotting analysis showed that BMP-2/PELA/VEG promoted the differentiation of rMSCs into osteoblasts via the MAPK and Wnt pathways. Osteoblast differentiation was assessed through alkaline phosphatase expression. When compared with simple BMP-2 plus VEGF group and pure PELA group, osteoblast differentiation in BMP-2/PELA/VEGF group significantly increased. An MTT assay indicated that BMP-2-loaded PELA scaffolds had no adverse effects on cell activity. BMP-2/PELA/VEG promoted the differentiation of rMSCs into osteoblast via the ERK1/2 and Wnt pathways. Our findings indicate that the sequential release of BMP-2 and VEGF from PELA microcapsule-based scaffolds is a promising approach for the treatment of bone defects.

Energy Migration Upconversion in Ce(III)-Doped Heterogeneous Core-Shell-Shell Nanoparticles

One major challenge in upconversion research is to develop new materials and structures to expand the emission spectrum. Herein, a heterogeneous core-shell-shell nanostructure of NaYbF₄ :Gd/Tm@NaGdF₄ @CaF₂ :Ce is developed to realize efficient photon upconversion in Ce³⁺ ions through a Gd-mediated energy migration process. The design takes advantage of CaF₂ host that reduces the 4f-5d excitation frequency of Ce³⁺ to match the emission line of Gd³⁺ . Meanwhile, CaF₂ is isostructural with NaGdF₄ and can form a continuous crystalline lattice with the core layer. As a result, effective Yb³⁺ → Tm³⁺ → Gd³⁺ → Ce³⁺ energy transfer can be established in a single nanoparticle. This effect enables efficient ultraviolet emission of Ce³⁺ following near infrared excitation into the core layer. The Ce³⁺ upconversion emission achieved in the core-shell-shell nanoparticles features broad bandwidth and long lifetime, which offers exciting opportunities of realizing tunable lasing emissions in the ultraviolet spectral region.

Broadband Ce(III)-Sensitized Quantum Cutting in Core-Shell Nanoparticles: Mechanistic Investigation and Photovoltaic Application

Quantum cutting in lanthanide-doped luminescent materials is promising for applications such as solar cells, mercury-free lamps, and plasma panel displays because of the ability to emit multiple photons for each absorbed higher-energy photon. Herein, a broadband Ce³⁺-sensitized quantum cutting process in Nd³⁺ ions is reported though gadolinium sublattice-mediated energy migration in a NaGdF₄:Ce@NaGdF₄:Nd@NaYF₄ nanostructure. The Nd³⁺ ions show downconversion of one ultraviolet photon through two successive energy transitions, resulting in one visible photon and one near-infrared (NIR) photon. A class of NaGdF₄:Ce@NaGdF₄:Nd/Yb@NaYF₄ nanoparticles is further developed to expand the spectrum of quantum cutting in the NIR. When the quantum cutting nanoparticles are incorporated into a hybrid crystalline silicon (c-Si) solar cell, a 1.2-fold increase in short-circuit current and a 1.4-fold increase in power conversion efficiency is demonstrated under short-wavelength ultraviolet irradiation. These insights should enhance our ability to control and utilize spectral downconversion with lanthanide ions.

Genetic diversity and paternal origin of domestic donkeys

Numerous studies have been conducted to investigate genetic diversity, origins and domestication of donkey using autosomal microsatellites and the mitochondrial genome, whereas the male-specific region of the Y chromosome of modern donkeys is largely uncharacterized. In the current study, 14 published equine Y chromosome-specific microsatellites (Y-STR) were investigated in 395 male donkey samples from China, Egypt, Spain and Peru using fluorescent labeled microsatellite markers. The results showed that seven Y-STRs-EcaYP9, EcaYM2, EcaYE2, EcaYE3, EcaYNO1, EcaYNO2 and EcaYNO4-were male specific and polymorphic, showing two to eight alleles in the donkeys studied. A total of 21 haplotypes corresponding to three haplogroups were identified, indicating three independent patrilines in domestic donkey. These markers are useful for the study the Y-chromosome diversity and population genetics of donkeys in Africa, Europe, South America and China.

Prediction of G gene epitopes of viral hemorrhagic septicemia virus and eukaryotic expression of major antigen determinant sequence

This study aims to express fish Viral hemorrhagic septicemia virus (VHSV) G main antigen domain by using Bac-to-bac expression system. Using bioinformatics tools, B cell epitope of VHSV G gene was predicted, and G main antigen domain was optimized. GM gene was inserted into pFastBac1 vector, then transferred recombinant plasmid into DH10Bac to get recombinant rBacmid-GM. Obtained shuttle plasmid rBacmid-GM was transfected into sf9 cells. GM expression was examined using by PCR and western-blot. Results indicated that G main antigen domain gene of VHSV was successfully cloned and sequenced which contains 1209 bp. PCR proved that shuttle plasmid rBacmid-GM was constructed correctly. SDS-PAGE electrophoresis analysis detected a band of protein about 45kD in expression product of G gene. Obtained recombinant G protein reacted with VHSV-positive serum that was substantiated by western-blot analysis. In conclusion, the main antigen domain of VHSV G was successfully expressed in the Bac-to-Bac baculovirus system.

Active control of bright electron beams with RF optics for femtosecond microscopy

A frontier challenge in implementing femtosecond electron microscopy is to gain precise optical control of intense beams to mitigate collective space charge effects for significantly improving the throughput. Here, we explore the flexible uses of an RF cavity as a longitudinal lens in a high-intensity beam column for condensing the electron beams both temporally and spectrally, relevant to the design of ultrafast electron microscopy. Through the introduction of a novel atomic grating approach for characterization of electron bunch phase space and control optics, we elucidate the principles for predicting and controlling the phase space dynamics to reach optimal compressions at various electron densities and generating conditions. We provide strategies to identify high-brightness modes, achieving ∼100 fs and ∼1 eV resolutions with 10⁶ electrons per bunch, and establish the scaling of performance for different bunch charges. These results benchmark the sensitivity and resolution from the fundamental beam brightness perspective and also validate the adaptive optics concept to enable delicate control of the density-dependent phase space structures to optimize the performance, including delivering ultrashort, monochromatic, high-dose, or coherent electron bunches.

Intestinal Batf3-dependent dendritic cells are required for optimal antiviral T-cell responses in adult and neonatal mice

Although we know a great deal about which types of dendritic cells (DCs) promote T-cell priming in the periphery, less is known about which DC subset(s) provoke antiviral responses within the gut. Here we report that conventional Zbtb46-dependent DCs were critically required for antiviral CD8⁺ T-cell responses against rotavirus (RV), the major cause of childhood gastroenteritis worldwide. Furthermore, we found that in adult mice, Batf3-dependent DCs were required for generating optimal RV-specific CD8⁺ T-cell responses. However, in contrast to mice that lack Zbtb46-dependent DCs, a significant amount of interferon gamma-producing RV-specific CD8⁺ T cells were still detected in the small intestine of RV-infected adult Batf3^-/- mice, suggesting the existence of compensatory cross-presentation mechanisms in the absence of Batf3-dependent DCs. In contrast to adult mice, we found that Batf3-dependent DCs were absolutely required for generating RV-specific CD8⁺ T-cell responses in neonates. Loss of Batf3-dependent DCs also resulted in a skewed polyclonal CD4⁺ T-cell response in both adult and neonatal mice upon RV infection, although local and systemic RV-specific immunoglobulin A production kinetics and titers were unimpaired. Our results provide insights that inform early-life vaccination strategies against RV infection.

Reduction in fecal microbiota diversity and short-chain fatty acid producers in Methicillin-resistant Staphylococcus aureus infected individuals as revealed by PacBio single molecule, real-time sequencing technology

Methicillin-resistant Staphylococcus aureus (MRSA) may cause potentially lethal infections. Increasing evidence suggests that the gut microbiota is associated with human health. Yet, whether patients with MRSA infections carry specific signatures in their fecal microbiota composition has not been determined. Thus, this study aimed to compare the fecal microbiota profile of MRSA-positive patients (n=15) with individuals without MRSA infection (n=15) by using the PacBio single molecule, real-time (SMRT) DNA sequencing system and real-time quantitative polymerase chain reaction (qPCR). Mann-Whitney tests and unweighted UniFrac principal coordinate analysis (PCoA) showed that the profile of fecal microbiota was apparently different between the two populations. Both the community richness and diversity were reduced in the MRSA-positive group (p<0.050). The genera Acinetobacter and Enterococcus were highly enriched in the MRSA-positive group, whereas less short-chain fatty acid (SCFA)-producing bacteria, including Butyricimonas, Faecalibacterium, Roseburia, Ruminococcus, Megamonas and Phascolarctobacterium, were detected in the MRSA-positive group. At species level, the species Acinetobacter baumannii and Bacteroides thetaiotaomicron were prevalent in the MRSA-positive group, whereas opposite trends were observed in 17 other species, such as Faecalibacterium prausnitzii, Lactobacillus rogosae, Megamonas rupellensis and Phascolarctobacterium faecium. Positive correlations were observed between Acinetobacter baumannii and erythrocyte sedimentation rate (ESR) (R=0.554, p=0.001), as well as hypersensitive C reactive protein (hsCRP) (R=0.406, p=0.026). Faecalibacterium prausnitzii was negatively associated with ESR (R=-0.545, p=0.002), hsCRP (R=-0.401, p=0.028) and total bile acids (TBA) (R=-0.364, p=0.048). In conclusion, the fecal microbiota structure was different between MRSA-positive and -negative patients. The increase in potential pathogens with the reduction of beneficial populations, such as SCFA-producing bacteria, in MRSA-positive patients may affect prognosis.

Premelting hcp to bcc Transition in Beryllium

Beryllium (Be) is an important material with wide applications ranging from aerospace components to x-ray equipment. Yet a precise understanding of its phase diagram remains elusive. We have investigated the phase stability of Be using a recently developed hybrid free energy computation method that accounts for anharmonic effects by invoking phonon quasiparticles. We find that the hcp → bcc transition occurs near the melting curve at 0<P<11  GPa with a positive Clapeyron slope of 41±4  K/GPa, which is more consistent with recent experimental measurements. This work also demonstrates the validity of this theoretical framework based on the phonon quasiparticle to study the structural stability and phase transitions in strongly anharmonic materials.

A novel scale-down cell culture and imaging design for the mechanistic insight of cell colonisation within porous substrate

At the core of translational challenges in tissue engineering is the mechanistic understanding of the underpinning biological processes and the complex relationships among components at different levels, which is a challenging task due to the limitations of current tissue culture and assessment methodologies. Therefore, we proposed a novel scale-down strategy to deconstruct complex biomatrices into elementary building blocks, which were resembled by thin modular substrate and then evaluated separately in miniaturised bioreactors using various conventional microscopes. In order to investigate cell colonisation within porous substrate in this proof-of-concept study, TEM specimen supporters (10-30 μm thick) with fine controlled open pores (100∼600 μm) were selected as the modular porous substrate and suspended in 3D printed bioreactor systems. Noninvasive imaging of human dermal fibroblasts cultured on these free-standing substrate using optical microscopes illustrated the complicated dynamic processes used by both individual and coordinated cells to bridge and segment porous structures. Further in situ analysis via SEM and TEM provided high-quality micrographs of cell-cell and cell-scaffold interactions at microscale, depicted cytoskeletal structures in stretched and relaxed areas at nanoscale. Thus this novel scaled-down design was able to improve our mechanistic understanding of tissue formation not only at single- and multiple-cell levels, but also at micro- and nanoscales, which could be difficult to obtain using other methods.