A fast species redistribution approach to accelerate the kinetic Monte Carlo simulation for heterogeneous catalysis

The first-principles kinetic Monte Carlo (kMC) simulation has been demonstrated as a reliable multiscale modeling approach in silico to disclose the interplay among all the elementary steps in a complex reaction network for heterogeneous catalysis. Heterogeneous catalytic systems frequently contain fast surface diffusion processes of some adsorbates while the elementary steps in it would be much slower than those in fast diffusion. Consequently, the kMC simulation for these systems is easily trapped in the sub-basins of a super basin on a potential energy surface due to the continuous and repeated sampling of these fast processes, which would significantly increase the total accessible simulation time and even make it impossible to get the reasonable simulation results using the kMC simulation. In this work, we present an improved fast species redistribution (FSR) method for the kMC simulation to overcome the stiffness problem resulting from the low-barrier surface diffusion to accelerate the heterogeneous catalytic kMC simulation. Taking CO oxidations on Pt(111) and Pt(100) as examples, we demonstrate that the FSR approach can properly reproduce the results of an equivalent first-principles microkinetic model simulation with more reasonable reaction rates. The improved kMC simulation based on the FSR method can accurately incorporate the effect of the fast diffusion of species on the surface and provide several orders of magnitude of acceleration compared to the standard kMC simulation.

Reduced expression of CENP-E contributes to the development of hepatocellular carcinoma and is associated with adverse clinical features

Human kinesin centromere-associated protein E (CENP-E), one of spindle checkpoint proteins, has been identified as a tumor suppressor in several types of cancer, however, its role in hepatocarcinogenesis remains unknown. Here we investigated the role of CENP-E in human hepatocellular carcinoma (HCC) employing HCC cell lines (Hep3B, SMMC7721, and QGY7701), animal models, and patient's clinical samples and data. We demonstrated that down-regulation of CENP-E by CENP-E-silencing shRNAs significantly promoted HCC proliferation/growth both in vitro and in vivo. Further studies found that CENP-E suppressed the proliferation of HCC cells by halting cell cycle progression at the G1-S phase and accelerating cell apoptosis. Analyses of HCC patient samples and clinical data revealed that CENP-E was significantly down-regulated in HCC tissues and low CENP-E expression was significantly associated with patient's adverse clinicopathological features: poor prognosis, advanced TNM stage, metastasis, and larger tumor size. Multivariate analysis indicated that CENP-E was an independent prognostic factor predicting outcomes of advanced HCC patients. Our data suggest that loss of CENP-E contributes to HCC development and is strongly associated with adverse HCC clinical pathology. Thus, CENP-E could be a novel target for new treatments and a useful prognostic biomarker for HCC patients.

Sex-Based Diverse Plaque Microbiota in Children with Severe Caries

Severe early childhood caries (S-ECC) is a multifactorial disease that can lead to suffering and reduced oral health-related quality of life in young children. The bacterial and fungal composition of dental plaque and how children's sex is associated with S-ECC are largely unknown. In this study, V4-16S rRNA and ITS1 rRNA gene amplicon sequencing was used to compare the plaque bacteriome and mycobiome of children <72 mo of age: 40 with S-ECC (15 males, 25 females) and 40 caries-free (19 males, 21 females). Health- and nutrition-related questionnaire data were also investigated. This study aimed to analyze potential sex-based differences in the supragingival plaque microbiota of young children with S-ECC and those caries-free. Behavioral and nutritional habit differences were observed between children with S-ECC and those caries-free and between male and female children. Overall, higher levels of Veillonella dispar, Streptococcus mutans, and other bacterial species were found in the S-ECC group as compared with caries-free controls (P < 0.05). A significant difference in the abundance of Neisseria was observed between males and females with S-ECC (P < .05). Fungal taxonomic analysis showed significantly higher levels of Candida dubliniensis in the plaque of children with S-ECC as compared with those caries-free (P < 0.05), but no differences were observed with Candida albicans (P > 0.05). Significant differences in the relative abundance of Mycosphaerella, Cyberlindnera, and Trichosporon fungal species were also observed between the caries-free and S-ECC groups (P < 0.05). Machine learning analysis revealed the most important bacterial and fungal species for classifying S-ECC versus caries-free. Different patterns of crosstalk between microbial species were observed between male and female children. Our work demonstrates that plaque microbiota and sex may be important determinants for S-ECC and could be factors to consider for inclusion in caries risk assessment tools.

[Analysis of follow-up information and pregnancy outcomes of cell free DNA prenatal screening]

Objective: To evaluate the efficacy of cell free DNA (cf-DNA) screening in prenatal care by analyzing the follow-up information and pregnancy outcomes. Methods: All cf-DNA cases conducted in Women's Hospital of Nanjing Medical University from August 2011 to December 2017 were enrolled. The general information of the pregnancies, cf-DNA results, confirmatory testing results, and the follow-up results were collected. The pregnancy outcomes were analyzed in cases with low risk cf-DNA results as well as with high risk results for common trisomies, which were trisomy 21 (T21), trisomy 18 (T18), and trisomy 13 (T13). The sensitivity, specificity, positive predictive value and negative predictive value of cf-DNA screening were calculated. Results: (1) A total of 43 615 cf-DNA cases were involved, with 44 cases (0.10%, 44/43 615) test failure results, 314 cases (0.72%, 314/43 571) high risk results for common trisomies and 43 257 cases (99.27%, 43 257/43 571) low risk results. (2) Among 277 cases (88.21%, 277/314) high risk cases were successfully followed up, and 228 cases (82.31%, 228/277) underwent invasive confirmatory prenatal diagnosis. In the low risk results, 36 826 cases (85.13%, 36 826/43 257) were successfully followed up, and 572 (1.55%, 572/36 826) cases were found to have adverse pregnancy outcomes, among which 4 false negative cf-DNA results were confirmed. (3) In the 37 103 successfully followed up cf-DNA cases, the sensitivity for T21, T18, T13 were calculated as 97.96%, 96.67% and 100.00%, respectively; the specificity for T21, T18, T13 were calculated as 99.96%, 99.95% and 99.95%, respectively. The positive predictive value for T21, T18, T13 were calculated as 90.57%, 63.04% and 17.39%, respectively. The negative predictive value for T21, T18, T13 were calculated as 99.99%, 99.98% and 100.00%. Conclusions: Cf-DNA is effective in detecting common trisomies, with a high sensitivity and specificity. However, the follow-up information revealed several potential limitations in current clinical practice, such as a number of cases with high risk results rejected invasive confirmatory testing, as well as the genetic diagnostic results for most low risk cases with an adverse pregnancy outcome aren't obtained. Genetic counseling and the follow-up for all the cf-DNA cases should be emphasized in the future.

Piezoelectric modulation of broadband photoresponse of flexible tellurium nanomesh photodetectors

Flexible photodetector shows great potential applications in intelligent wearable devices, health monitoring, and biological sensing. In this work, single crystal β-tellurium nanowires were grown on flexible muscovite by molecular beam epitaxy, constructing high-density ordered nanomesh structure. The prepared photodetectors based on tellurium nanomesh exhibit excellent mechanical flexibility, fast response in a broad range from ultraviolet to near-infrared, and good photosensitivity. We found that the flexible photodetectors with Shottky contact drastically suppressed dark current, while the response speed was lowered in comparison to the devices with ohmic contact, as holes would take a long time to tunnel through the Shottky barrier between metal and p-type Te. Moreover, the photoresponse of flexible Shottky photodetectors can be modulated by piezoelectricity of tellurium, and pronounced photocurrent increase after bending many times. Under external stress, polarization charges could tune Shottky barrier height of the metal/tellurium, resulting in variation of photocurrent. This research not only explores the broadband photoresponse and piezoelectric effect of tellurium nanomesh, but also promotes the integration and development of broadband flexible optoelectronic devices.

[Correlation between alanine aminotransaminase level and hepatocellular carcinoma in antiviral therapy of chronic viral hepatitis]

Alanine aminotransferase (ALT) is the most abundant enzyme in human liver cells. When liver lesions occur, the permeability of liver cell membrane is enhanced and ALT is released into the blood. Clinically, the nature and degree of liver lesions are understood by measuring the level of ALT in peripheral blood. Serum ALT levels after chronic hepatitis B virus (HBV) infection are associated with the risk of hepatocellular carcinoma (HCC), while the normalization of ALT in antiviral therapy for chronic hepatitis B (CHB) patients is an independent surrogate indicator for predicting HCC development.

[Primary Ewing's sarcoma of the temporal bone: a rare case]

SummaryEwing's sarcoma is a malignant, round cell tumor arising from the bones and primarily affecting children and adolescent. Involvement of the skull bones is rarely reported, constituting 1%-6% of the total Ewing's sarcoma cases. We describe a 33 years old male patient having Ewing sarcoma of the mastoid and petrous parts of temporal bone, whose clinical presentation mimicked mastoiditis with facial nerve palsy. We discuss the clinical and therapeutic course of an extensive primary Ewing sarcoma of the temporal bone and review this entity's literature in detail. The etiopathology of an acute peripheral facial palsy is often hard to identify. If the facial weakness starts together with symptoms suggesting an inflammatory process, the differential diagnosis may be focused first on diseases like herpes zoster oticus and a severe course of acute purulent otitis media. As an uncommon tumor of the temporal bone, physicians should consider Ewing's sarcoma in the differential diagnosis of children and adolescents who present with facial nerve paralysis. And in the case of ambiguous clinical findings, a surgical exposure of the middle ear is recommended.

An effective structural descriptor to quantify the reactivity of lattice oxygen in CeO2 subnano-clusters

Subnano-clusters are commonly the important active components on many catalysts in heterogeneous catalysis and finding an effective structural descriptor is key to designing new catalysts. However, the progress of obtaining such a descriptor falls far-short of expectation due to their well-known complicated structures. Herein, we propose a function of sigmoid coordination number (f(SCN)) as a structural descriptor, and develop an explicit equation to predict adsorption energies on Ce_nO_2n (n = 1-10) subnano-clusters using H adsorption as an example because of the importance of (de)hydrogenation in heterogeneous catalysis. We show an excellent linear correlation between H-adsorption energies and f(SCN) with RMSE = 0.05 eV and R² = 0.97. The generality of this equation is also verified using other different sizes Ce_nO_2n (n = 12-14) subnano-clusters with RMSE = 0.02 eV. We demonstrate that the structural descriptor not only provides an excellent quantitative structure-reactivity relationship for metal oxide clusters, but also deepens the understanding of structure-reactivity relationship, which may have far-reaching implications in heterogeneous catalysis.

Achieving rational design of alloy catalysts using a descriptor based on a quantitative structure–energy equation

Rational design of high-activity alloy catalysts for NO oxidation.

Systematic analysis of copy-number variations associated with early pregnancy loss

OBJECTIVES

Embryonic numerical and structural chromosomal abnormalities are the most common cause of early pregnancy loss. However, the role of submicroscopic copy-number variations (CNVs) in early pregnancy loss is unclear, and little is known about the critical regions and candidate genes for miscarriage, because of the large size of structural chromosomal abnormalities. The aim of this study was to identify potential miscarriage-associated submicroscopic CNVs and critical regions of large CNVs as well as candidate genes for miscarriage.

METHODS

Over a 5-year period, 5180 fresh miscarriage specimens were investigated using quantitative fluorescent polymerase chain reaction/CNV sequencing or chromosomal microarray analysis. Statistically significant submicroscopic CNVs were identified by comparing the frequency of recurrent submicroscopic CNVs between cases and a published control cohort. Furthermore, genes within critical regions of miscarriage-associated CNVs were prioritized by integrating the Residual Variation Intolerance Score and the human gene expression dataset for identification of potential miscarriage candidate genes.

RESULTS

Results without significant maternal-cell contamination were obtained in 5003 of the 5180 (96.6%) cases. Clinically significant chromosomal abnormalities were identified in 59.1% (2955/5003) of these cases. Three recurrent submicroscopic CNVs (microdeletions in 22q11.21, 2q37.3 and 9p24.3p24.2) were significantly more frequent in miscarriage cases, and were considered to be associated with miscarriage. Moreover, 44 critical regions of large CNVs were observed, including 14 deletions and 30 duplications. There were 309 genes identified as potential miscarriage candidate genes through gene-prioritization analysis.

CONCLUSIONS

We identified potential miscarriage candidate CNVs and genes. These data demonstrate the importance of CNVs in the etiology of miscarriage and highlight the importance of ongoing analysis of CNVs in the study of miscarriage. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

An approach to calculate the free energy changes of surface reactions using free energy decomposition on ab initio brute-force molecular dynamics trajectories

To understand the mechanisms and kinetics of catalytic reactions in heterogeneous catalysis, ab initio molecular dynamics is one of the powerful methods used to explore the free energy surface (FES) of surface elementary steps.

Understanding supported noble metal catalysts using first-principles calculations

Heterogeneous catalysis on supported and nonsupported nanoparticles is of fundamental importance in the energy and chemical conversion industries. Rather than laboratory analysis, first-principles calculations give us an atomic-level understanding of the structure and reactivity of nanoparticles and supports, greatly reducing the efforts of screening and design. However, unlike catalysis on low index single crystalline surfaces, nanoparticle catalysis relies on the tandem properties of a support material as well as the metal cluster itself, often with charge transfer processes being of key importance. In this perspective, we examine current state-of-the-art quantum-chemical research for the modeling of reactions that utilize small transition metal clusters on metal oxide supports. This should provide readers with useful insights when dealing with chemical reactions on such systems, before discussing the possibilities and challenges in the field.

Bio-inspired iron-catalyzed oxidation of alkylarenes enables late-stage oxidation of complex methylarenes to arylaldehydes

It is a long-standing challenge to achieve efficient and highly selective aerobic oxidation of methylarenes to benzaldehydes, owing to overoxidation problem stemming from the oxidizability of benzaldehyde far higher than the toluene under usual aerobic conditions. Herein we report a bio-inspired iron-catalyzed polymethylhydrosiloxane-promoted aerobic oxidation of methylarenes to benzaldehydes with high yields and selectivities. Notably, this method can tolerate oxidation-labile and reactive boronic acid group, which is normally required to be transformed immediately after its introduction, and represents a significant advance in the area of the chemistry of organoboronic acids, including the ability to incorporate both aldehyde and ketone functionalities into unprotected arylboronic acids, a class that can be difficult to access by current means. The robustness of this protocol is demonstrated on the late-stage oxidation of complex bioactive molecules, including dehydroabietic acid, Gemfibrozil, Tocopherol nicotinate, a complex polyol structure, and structurally complex arylboronic acids.

Oxidation of toluenes to benzaldehydes is usually accompanied by overoxidation products. Here, the authors report an iron-catalysed aerobic oxidation of methylarenes to benzaldehydes with high yields and selectivities, even in presence of boronic acid groups and in complex natural products and drugs.

DFT study of furfural conversion on a Re/Pt bimetallic surface: synergetic effect on the promotion of hydrodeoxygenation

Density functional theory (DFT) calculations of furfural conversion were performed via hydrogenation and hydrodeoxygenation pathways on a bimetallic surface, namely, a thin oxygen-covered Re film on Pt(111). In the most stable adsorption conformation, the furyl ring component adsorbs on the Re edge site and the carbonyl oxygen also plays an important role in the adsorption strength. It was found that, while furfural conversion is kinetically favoured in the hydrogenation route to generate furfuryl alcohol, the hydrodeoxygenation mechanism to generate 2-methylfuran and water is thermodynamically favoured. Our results show that the hydrodeoxygenation product 2-methylfuran is achievable via the hydrogenation of furfural into hydroxyalkyl species, followed by C-OH bond cleavage, and successive hydrogenations of the furyl-CH intermediate. However, the production of 2-methylfuran is prohibited as the oxidised Re surface cannot accept further oxygen deposition, due to the oxygen-related species are difficult to remove in the form of water via hydrogenation. By comparing the results from the Re/Pt system to those on a monometallic flat Pt surface, we were able to demonstrate that incorporation of the oxophilic metals to active metals for hydrogenation could promote the hydrodeoxygenation route by reducing the barrier of C-O bond cleavage.

[Interpretations of EASL 2017 clinical practice guidelines on the management of hepatitis B virus infection]

The European Association for the Study of the Liver recently released the updated Clinical Practice Guidelines on the management of hepatitis B virus infection at the International Liver Congress(TM) 2017 in Amsterdam. The latest clinical practice guideline integrated the latest scientific advances on diagnosis and therapy of hepatitis B, thereby providing optimize the management of patients with either acute or chronic HBV. The latest clinical practice guideline includes new definitions of disease phases, expanded indications for initiating treatment, prevention of mother-to-child transmission, new stopping rules for antiviral therapy. Future treatment strategies to achieve 'cure' of disease and new biomarkers are discussed.

[The expression of P19ink4d in the pathogenesis and development of hearing loss]

Objective: This study aimed to investigate the P19ink4d expression in cochlea of mice model with noise induced hearing loss and the role of P19ink4d in the degeneration of inner ear cells. It also searched for P19ink4d gene alterations in patients with profound sensorineural deafness.Method: CBA/J mice were exposed to broad band noise at 101 dB SPL for 2 hours, auditory brainstem response (ABR) were examined to confirm noise lead to the permanent threshold shift. Immunohistochemical staining, Western blotting, and real-time polymerase chain reaction (PCR) were performed on cochlear tissues, to elucidate changes in P19ink4d expression in mice after noise exposure. For clinical evaluation, 400 children from unrelated families with severe or profound sensorineural hearing loss (SNHL) were recruited, genomic DNA was obtained from the patients and was subjected to DNA microarray to screen mutations in 4 most common genes. The sample that carried none of the common mutant alleles were subjected to PCR and sequenced to detect mutations in P19ink4d gene.Result: The ABR threshold shift of mice in the experimental group significantly increased after noise exposure and was higher than that in the null-noise group. The ABR of 1 day post noise was least among experimental groups and there is no statistical different between ABR of 7 days and 14 days post noise. The missing of outer hair cells occurred after noise exposure, while the inner hair cells hardly miss. It was found that the P19ink4d expression increased significantly in the inner ear cells 3 hours after noise exposure, then recovered in 24 hours. Western blot indicated that the amount of P19ink4d increased transitorily 3-6 h after the noise. However, no mutation existed within the coding exons of P19ink4d in the patients with profound sensorineural deafness.Conclusion: The results support the concept that P19ink4d may play an important role in the pathogenesis and development of noise induced hearing loss.

Correlations between the level of antibody against peptide of glutamate receptor NR3B subunit in the CSF and cognitive comorbidities of patients with epilepsy

OBJECTIVE

Autoimmune epilepsy is an under-recognized condition, and the mechanisms of antibody-mediated epileptogenesis are unknown. The N-methyl-D-aspartate (NMDA) receptor subunit 3 peptide B (NR3B) modulates Mg2+ sensitivity and Ca2+ mobilization of glutamate responses in the central nervous system (CNS). The levels of antibodies against NR3B (NR3B Ab's) in the cerebrospinal fluid (CSF) and the correlations between NR3B Ab's and cognitive comorbidities of epilepsy patients remain unclear.

PATIENTS AND METHODS

CSF samples were collected from 36 patients with consecutive epilepsy and 17 healthy controls. The levels of NR3B Ab's in the CSF were measured by ELISA. The cognitive function was assessed by Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE).

RESULTS

The results showed that the levels of NR3B Ab's were significantly higher in patients with epilepsy than those in the controls (p<0.01). Thirteen of 36 patients had higher levels of NR3B Ab's exceeding mean+ 2SD of all patients, and the scores of MMSE and MoCA of these 13 patients were significantly lower than the other 23 patients and controls (p<0.01; p<0.001). However, there were no significant differences in the scores of MMSE and MoCA between the 23 patients and the controls. Correlation analysis indicated a significant negative correlation between the levels of NR3B Ab's and the scores of MMSE (correlation coefficient: r=-0.543; p<0.01) or the scores of MoCA (correlation coefficient: r=-0.548; p<0.01).

CONCLUSIONS

We suggest that some patients with epilepsy may have immune process after onset and the presence of NR3B Ab's may be associated with cognitive comorbidities in patients with epilepsy.

Evidence of the O–Pd–O and Pd–O4 structure units as oxide seeds and their origin on Pd(211): revealing the mechanism of surface oxide formation

The formation of surface oxides on metal surfaces is not only important in materials science, but also of significance in heterogeneous catalysis due to the fact that during most oxidation reactions the metal catalysts are inevitably oxidized, which may cause dramatic consequences in the reactions.

A DFT study of direct furfural conversion to 2-methylfuran on the Ru/Co3O4 surface

We investigate the direct conversion of furfural to 2-methylfuran on Ru/Co₃O₄ using DFT calculations.

Interface-tuned selective reductive coupling of nitroarenes to aromatic azo and azoxy: a first-principles-based microkinetics study

It is of great importance to regulate a catalyst to control its selectivity. In general, the Pt catalyzed hydrogenation of nitrobenzene (PhNO₂) would produce aniline.

Interconversion of hydrated protons at the interface between liquid water and platinum

The free energy barriers for hydrogen transfer at the H₂O/Pt(111) interface calculated usingab initiomolecular dynamics and umbrella sampling.

Iron-catalyzed oxidative C–C(vinyl) σ-bond cleavage of allylarenes to aryl aldehydes at room temperature with ambient air

The iron-catalyzed C−C single bond cleavage and oxidation of allylarenes without the assistance of heteroatoms/directing groups to produce aryl aldehydes is disclosed.

Clinical relevance of the multidrug resistance‑associated protein 1 gene in non‑small cell lung cancer: A systematic review and meta‑analysis

The multidrug resistance‑associated protein 1 (MRP1) gene has been found to be consistently overexpressed in the majority of patients with non‑small cell lung cancer (NSCLC). MRP1 is known for its ability to actively decrease intracellular drug concentration, limiting the efficacy of cancer chemotherapy; however, data on the clinical relevance of MRP1 is inconclusive. In the present meta‑analysis, all available published data were combined to provide an updated view on the clinicopathological relevance of MRP1 in patients with NSCLC. A systematic search was conducted to obtain relevant studies published in English, Chinese and Japanese databases. All data from patients with NSCLC who underwent testing for MRP1, by either immunohistochemistry or reverse transcription‑polymerase chain reaction, were extracted and combined for further analysis. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for each selected study, with either the fixed‑effects model or the random‑effects model where appropriate. The quality of methodology, heterogeneities and publication bias of the included articles were also analyzed. A total of 36 clinical studies involving 3,278 patients were included in the study. It was found that the increased expression of the MRP1 gene was associated with the following subgroups of patients: Non‑smokers vs. smokers (OR, 2.54; 95% CI, 1.17‑5.54; P=0.019); adenocarcinoma vs. squamous cell carcinoma (OR, 1.58; 95% CI, 1.16‑2.17; P=0.004); clinical stage III‑IV vs. stage I‑II (OR, 1.36; 95% CI, 1.11‑1.66; P=0.003); lymph node metastases (OR, 1.32; 95% CI, 1.09‑1.61; P=0.005); poor response to chemotherapy (OR, 0.41; 95% CI, 0.23‑0.72; P=0.002) and reduced 3‑year survival rate (OR, 0.40; 95% CI, 0.23‑0.68; P=0.001). In conclusion, the findings from this study suggest that increase in MRP1 gene expression is associated with being a non‑smoker, adenocarcinoma, advanced clinical stages and a poor response to chemotherapy in patients with NSCLC. The results from the most extensive and updated data on MRP1 support the requirement for continued investigation into the potential use of MRP1 as a biomarker/clinical indicator for NSCLC.

[Changes and clinical significance of γδT cells in peripheral blood of patients with chronic hepatitis B during pegylated interferon α-2a treatment]

Objective: To observe the changes of γδT cells in the peripheral blood of patients with chronic hepatitis B (CHB) during pegylated interferon α-2a treatment, and to analyze the correlation between clinical indicators and curative effects. Methods: Peripheral blood of hepatitis B e antigen (HBeAg)-positive CHB patients were collected at different time points of Peg-IFNα-2a treatment, including 17 patients at 0 weeks, 20 patients at 12 weeks, 20 patients at 24 weeks, and 16 patients at 48 weeks. From these 11 patients, blood samples were frequently observed at 0, 12, 24, and 48 weeks of treatment. The frequencies of γδT and its subpopulation cells Vδ1T, Vδ2T, effector memory γδT (γδTem), central memory γδT (γδTcm), initial γδT (γδTnaive) and terminal differentiation effect γδT (γδTeff) cells in peripheral blood were detected by flow cytometry. Liver function, serum HBV markers and HBV DNA levels were measured simultaneously. SPSS 23.0 statistical software was used to analyze the differences in cell proportions at each treatment time point, and the correlation between cell proportions and alanine aminotransferase (ALT), HBsAg, HBeAg or HBV DNA levels. In addition, the correlation between the proportions of γδT and its subpopulation cells and the response to Peg-IFNα-2a treatment in the 11 patients with continuous follow-up were analyzed. Results: The percentage of γδT and Vδ2T cells in peripheral blood of patients with CHB decreased gradually during the period of 0-48 weeks of Peg-IFNα-2a treatment. The percentages of γδT cells and Vδ2T cells at 48 weeks were 6.89% (5%, 8.15%), 4.61% (2.16%, 6.50%), respectively; significantly lower than the 0 week [12.5% ​​(7.73%, 19%), 6.59% (3.86%, 13.62%)], the differences were statistically significant (P < 0.05). The proportions of Vδ1T, γδTem, γδTcm, γδTnaive, or γδTeff subpopulations were not statistically different at each time points (all P > 0.05). At the same time, the levels of ALT, HBsAg, HBeAg or HBV DNA were positively correlated with the ratio of γδT or Vδ2T cells (P < 0.05). Among the 11 patients with continuous followed- up, the proportion of γδTem cells in responders was significantly lower than that of non-responders at each time points, and the difference was statistically significant (P < 0.05). There was no statistically significant difference between the two groups (all P > 0.05). Conclusion: The proportion of γδT cells in the course of CHB treatment with Peg-IFNα-2a reduces the liver inflammation by decreasing the replication of HBV virus. Chronic hepatitis B patients with a lower proportion of effector memory (γδTem) cells may be more likely to get better response with Peg-IFNα-2a.

Copy Number Variations with Isolated Fetal Ventriculomegaly

BACKGROUND

Copy Number Variations (CNVs) are an important genetic cause of a number of neurodevelopmental disorders (NDs). However, the association between CNVs and the development and prognosis of fetal isolated mild ventriculomegaly (IMV) is unclear.

OBJECTIVES

To investigate possible associations between CNVs and the development of fetal IMV.

METHODS

This retrospective study recruited 154 subjects with ultrasound-confirmed fetal IMV and 190 subjects in a control cohort who underwent a high-risk prenatal serum screening program. The exclusion criteria included fetus G-banding chromosomal abnormality or positive fetus TORCH infection. DNA samples from all 344 fetuses were examined by an SNP-array. Developmental outcomes were assessed during postnatal follow-up.

RESULTS

Fourteen pathogenic CNVs (pCNVs) were identified in 13 out of 154 IMV fetuses. Three pCNVs were found in 3 out of 190 subjects in the prenatal screening high-risk cohort, with a significant difference (P value=0.016, X2 test). Notably, the 14 pCNVs detected in the IMV cohort were all associated with neurodevelopmental disorders (NDs), including autism, intellectual disability. Among the 13 IMV fetuses carrying pCNVs, five subjects were found in the postnatal follow-up to manifest NDs, including two with autism and three with mild neurodevelopmental delay. The other 8 subjects consisted of three normal infants younger than 12-months old, two lost in the follow-up, and three with the termination of pregnancy. Out of 141 IMV subjects without detectable pCNVs, 123 subjects showed normal development, 16 were lost in the follow-up, 2 subjects terminated the pregnancy due to fetal hydrocephalus or congenital heart disease in the late fetus development.

CONCLUSIONS

This study suggests an association between pCNVs and fetal IMV. pCNVs may be involved in the pathological process of fetal IMV and postnatal NDs. Identifying specific genomic alterations may provide an insight into pathogenetic mechanism and aid better diagnosis and prognosis of neurodevelopmental outcomes in fetal IMV.

Systematic review with meta-analysis: combination treatment of regimens based on pegylated interferon for chronic hepatitis B focusing on hepatitis B surface antigen clearance

BACKGROUND

The seroclearance of hepatitis B surface antigen (HBsAg) in patients with chronic hepatitis B (CHB) is considered to be associated with favourable clinical outcomes.

AIMS

This meta-analysis was performed to establish the proportion of HBsAg loss rates among CHB patients who received combination treatment based on pegylated interferon (PegIFN). Four combination strategies have been studied with the aim of improving HBsAg loss: "de novo," "NA-experienced," "switch-to" and "add-on." This meta-analysis was performed to determine which, if any, of these combination strategies was more effective.

METHODS

Medline, Web of Science and Embase databases were searched from inception to December 2017. The proportion of patients who achieved HBsAg loss after combination therapy was pooled using a random-effects model.

RESULTS

Twenty-four studies fulfilled the meta-analysis criteria. The overall pooled proportion suggested that the rate of HBsAg loss could be increased to 9% (95% CI: 7%-12%) based on the combination treatment in CHB patients. Compared with "de novo" strategy (8%, 95% CI: 6%-10%), the "nucleos(t)ide analogues-experienced" (11%, 95% CI: 8%-15%) was found to be more likely (P = 0.036) to achieve a response. Compared with the "add-on" strategy (8%, 95% CI: 5%-13%), the "switch-to" (14%, 95% CI: 9%-20%) was found to be more likely (P = 0.012) to achieve HBsAg loss.

CONCLUSION

The "nucleos(t)ide analogues-experienced" strategy was more effective than the "De novo" strategy in achieving HBsAg loss for CHB patients. Combination treatment using regimens based on Peg-IFN may be useful to help nucleos(t)ide analogues-treated patients, who have experienced at least 48 weeks of nucleot(s)ide analogue, achieve HBsAg seroclearance.

Topographical cues of direct metal laser sintering titanium surfaces facilitate osteogenic differentiation of bone marrow mesenchymal stem cells through epigenetic regulation

OBJECTIVES

To investigate the role of hierarchical micro/nanoscale topography of direct metal laser sintering (DMLS) titanium surfaces in osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), as well as the possible underlying epigenetic mechanism.

MATERIALS AND METHODS

Three groups of titanium specimens were prepared, including DMLS group, sandblasted, large-grit, acid-etched (SLA) group and smooth titanium (Ti) group. BMSCs were cultured on discs followed by surface characterization. Cell adhesion and proliferation were examined by SEM and CCK-8 assay, while osteogenic-related gene expression was detected by real-time RT-PCR. Immunofluorescence, western blotting and in vivo study were also performed to evaluate the potential for osteogenic induction of materials. In addition, to investigate the underlying epigenetic mechanisms, immunofluorescence and western blotting were performed to evaluate the global level of H3K4me3 during osteogenesis. The H3K4me3 and H3K27me3 levels at the promoter area of the osteogenic gene Runx2 were detected by ChIP assay.

RESULTS

The DMLS surface exhibits greater protein adsorption ability and shows better cell adhesion performance than SLA and Ti surfaces. Moreover, both in vitro and in vivo studies demonstrated that the DMLS surface is more favourable for the osteogenic differentiation of BMSCs than SLA and Ti surfaces. Accordingly, osteogenesis-associated gene expression in BMSCs is efficiently induced by a rapid H3K27 demethylation and increase in H3K4me3 levels at gene promoters upon osteogenic differentiation on DMLS titanium surface.

CONCLUSIONS

Topographical cues of DMLS surfaces have greater potential for the induction of osteogenic differentiation of BMSCs than SLA and Ti surfaces both in vitro and in vivo. A potential epigenetic mechanism is that the appropriate topography allows rapid H3K27 demethylation and an increased H3K4me3 level at the promoter region of osteogenesis-associated genes during the osteogenic differentiation of BMSCs.