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Abstract Background The application of calcium phosphate (CaP)-based bone substitutes plays an important role in periodontal regeneration, implant dentistry and alveolar bone reconstruction. The incorporation of strontium (Sr) into CaP-based bone substitutes appears to improve their biological properties, but the reported in vivo bone repair performance is inconsistent among studies. Herein, we conducted a systematic review and meta-analysis to investigate the in vivo performance of Sr-doped materials. Methods We searched PubMed, EMBASE (via OVIDSP), and reference lists to identify relevant animal studies. The search, study selection, and data extraction were performed independently by two investigators. Meta-analyses and sub-group analyses were conducted using Revman version 5.4.1. The heterogeneity between studies were assessed by I2. Publication bias was investigated through a funnel plot. Results Thirty-five studies were finally enrolled, of which 16 articles that reported on new bone formation (NBF) were included in the meta-analysis, covering 31 comparisons and 445 defects. The overall effect for NBF was 2.25 (95% CI 1.61–2.90, p

Series connection of multiple transistors is an attractive solution to achieve higher voltage capability. However, the voltage imbalance among the series-connected devices is a critical issue caused by mismatches of device characteristics and gate signals. To prevent the failure of devices from the voltage imbalance, voltage balancing control (VBC) is required. In this work, an active VBC for series-connected silicon carbide (SiC) mosfet submodules is proposed with a pulsewidth modulation (PWM) method. A submodule consists of two switches and one shunt capacitor, and the PWM method actively controls the capacitor voltages for balancing. The proposed VBC is simulated in MATLAB/Simulink and experimentally verified with six series-connected SiC mosfet submodules at up to 150 kHz. The voltage balancing is achieved within 3.9% of the targeted balanced voltage.

The Advent of modern power electronics has brought tremendous impact on emerging power systems. In an emerging smart grid, as the number of inverter- and converter-based devices increases to more than hundreds of thousands, it is rather intuitive that the state-of-the-art technical solutions and industry practices will no longer be sustainable. The combination of power electronics and advanced control technologies serve as the key enabler of a wide range of smart grid applications. While tremendous progress has been made in advancing the standalone power electronics technologies, much less attention has been paid to bridging the gap between traditionally disjoint research areas – power electronics, power systems, and intelligent control – ultimately facilitating the vision of 100% carbonneutral energy systems come to fruition. There is a growing interest in the concepts of power electronics-enabled power systems around the world. This special section includes two high-quality papers, which cover the trending topic on the control strategy for inverters that are essential for Smart Grid applications.

Objectives: The prevalence of G6PD deficiency has not been reported in Yangjiang, a western city in Guangdong province. This study aims to investigate the molecular characteristics of G6PD deficiency in this region. Methods: Blood samples were collected from adults at a local hospital to screen for G6PD deficiency. The deficient samples were subjected to further analysis using PCR and reverse dot blot to determine the specific G6PD variants. Results: Among the 3314 male subjects, 250 cases of G6PD deficiency were found using the G6PD enzyme quantitative assay, resulting in a prevalence of 7.54% (250/3314) in the Yangjiang region. The prevalence of G6PD deficiency in females was 3.42% (176/5145). Out of the 268 cases of G6PD deficiency tested for G6PD mutations, reverse dot blot identified 20 different G6PD variants. The most common G6PD variant was c.1388G>A (81/268), followed by c.1376G>T (48/268), c.95A>G (32/268), c.1024C>T (9/268), c.392G>T (7/268), and c.871G>A/c.1311C>T (6/268). It was observed that c.871G>A was always linked to the polymorphism of c.1311C>T in this population. Conclusion: This investigation into G6PD deficiency in this area is expected to significantly improve our understanding of the prevalence and molecular characterization of this condition. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) have been demonstrated for their involvement in virus biology and pathogenesis, including functioning as key determinants of virally-induced cancers. As an important oncogenic α-herpesvirus affecting poultry health, Marek’s disease virus serotype 1 [Gallid alphaherpesvirus 2 (GaHV-2)] induces rapid-onset T-cell lymphomatous disease commonly referred to as Marek’s disease (MD), an excellent biological model for the study of virally-induced cancer in the natural hosts. Previously, we have demonstrated that GaHV-2-encoded miRNAs (especially those within the Meq-cluster) have the potential to act as critical regulators of multiple processes such as virus replication, latency, pathogenesis, and/or oncogenesis. In addition to miR-M4-5p (miR-155 homolog) and miR-M3-5p, we have recently found that miR-M2-5p possibly participate in inducing MD lymphomagenesis. Here, we report the identification of two tumor suppressors, the RNA-binding protein 24 (RBM24) and myogenic differentiation 1 (MYOD1), being two biological targets for miR-M2-5p. Our experiments revealed that as a critical miRNA, miR-M2-5p promotes cell proliferation via regulating the RBM24-mediated p63 overexpression and MYOD1-mediated IGF2 signaling and suppresses apoptosis by targeting the MYOD1-mediated Caspase-3 signaling pathway. Our data present a new strategy of a single viral miRNA exerting dual role to potentially participate in the virally-induced T-cell lymphomagenesis by simultaneously promoting the cell proliferation and suppressing apoptosis.

Objective: To investigate the mechanism underlying the effects of berberine (BBR) in the treatment of Alzheimer's disease (AD). Methods: 3xTg AD mice were treated with BBR for 3months, then the open field test (OFT), the novel object recognition test (NOR) and the Morris water maze (MWM) test were performed to assess behavioral performance. Hematoxylin-eosin (HE) staining, Nissl staining were used to examine histopathological changes. The pharmacological and molecular properties of BBR were obtained from the TCMSP database. BBR-associated AD targets were identified using the PharmMapper (PM), the comparative toxicogenomics database (CTD), DisGeNet and the human gene database (GeneCards). Core networks and BBR targets for the treatment of AD were identified using PPI network and functional enrichment analyses. AutoDock software was used to model the interaction between BBR and potential targets. Finally, RT-qPCR, western blotting were used to validate the expression of core targets. Results: Behavioral experiments, HE staining and Nissl staining have shown that BBR can improve memory task performance and neuronal damage in the hippocampus of AD mice. 117 BBR-associated targets for the treatment of AD were identified, and 43 genes were used for downstream functional enrichment analysis in combination with the results of protein-protein interaction (PPI) network analysis. 2,230 biological processes (BP) terms, 67 cell components (CC) terms, 243 molecular function (MF) terms and 118 KEGG terms were identified. ALB, EGFR, CASP3 and five targets in the PI3K-AKT signaling pathway including AKT1, HSP90AA1, SRC, HRAS, IGF1 were selected by PPI network analysis, validated by molecular docking analysis and RT-q PCR as core targets for further analysis. Akt1 mRNA expression levels were significantly decreased in AD mice and significantly increased after BBR treatment (p<0.05). Besides, AKT and ERK phosphorylation decreased in the model group, and BBR significantly increased their phosphorylation levels. Conclusion: AKT1, HSP90AA1, SRC, HRAS, IGF1 and ALB, EGFR, CASP3 were core targets of BBR in the treatment of AD. BBR may exert a neuroprotective effect by modulating the ERK and AKT signaling pathways. [ABSTRACT FROM AUTHOR]

Objective(s): Osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) is an essential stage in bone formation. Autophagy plays a pivotal role in the self-renewal potential and pluripotency of stem cells. This study aimed to explore the function of autophagy-related genes during osteogenic differentiation of BMSCs. Materials and Methods: The differentially expressed autophagy-related genes (ARGs) were obtained from the GEO and HADb databases. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed using R software. The PPI and hub gene mining networks were constructed using the STRING database and Cytoscape. Finally, the RT-qPCR was conducted to validate the expression level of ARGs in BMSCs. Results: Thirty-seven differentially expressed ARGs were finally obtained, including 12 upregulated and 25 downregulated genes. GO and KEGG enrichment analysis showed that most of these genes were enriched in apoptosis and autophagy. The PPI network revealed strong interactions between differentially expressed ARGs. The expression level of differentially expressed ARGs tested by RTqPCR showed 6 upregulated ARGs, including FOXO1, MAP1LC3C, CTSB, FOXO3, CALCOCO2, FKBP1A, and 4 downregulated ARGs, including MAPK8IP1, NRG1, VEGFA, and ITGA6 were consistent with the expression of high-throughput sequencing data. Conclusion: We identified 37 ARGs during osteogenic differentiation using bioinformatics analysis. FOXO1, MAP1LC3C, CTSB, FOXO3, CALCOCO2, FKBP1A, MAPK8IP1, NRG1, VEGFA, and ITGA6 may regulate osteogenic differentiation of hBMSCs by involving autophagy pathway. This study provides new insight into the osteogenic differentiation of hBMSCs and may be available in developing therapeutic strategies for maxillofacial bone defects. [ABSTRACT FROM AUTHOR]

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This paper focuses on analysis and suppression of circulating harmonic currents in a modular multilevel converter (MMC) considering the impact of dead time in medium-voltage applications. A continuous equivalent model of the MMC containing two ideal transformer models is presented. Using this model, the impact of a harmonic voltage upon the dc side is analyzed and the production mechanism of circulating harmonic currents is elucidated. At the same time, the impact of dead time and insulated gate bipolar transistor (IGBT) voltage drop (DTVD) is studied, which indicates that capacitor voltages, output harmonics, and circulating harmonic currents are influenced. Based on this analysis, an open-loop control strategy to suppressing circulating harmonic currents caused by the output current and DTVD is presented. Finally, all these conclusions are verified using a simulation platform with 14 modules per arm fed by a 14-kV dc voltage source and a downscaled experimental platform with four modules per arm fed by a 560-V dc voltage source. [ABSTRACT FROM AUTHOR]

DC arc fault introduces major safety concerns in a wide variety of components in dc networks. However, the randomness and instability of dc arc makes it difficult to be detected. In this paper, an experimental system was designed and tested at different load current, dc source voltage, and gap length to evaluate the impact of each parameter to the dc arc. Based on the experimental results, characteristics in the electrical behavior were studied and fault detection oriented analysis was conducted. A detection algorithm utilizing both time and time-frequency domain characteristics was proposed to differentiate between dc arc fault and normal condition. The detection algorithm was then realized on a digital signal processing board and tested to verify the effectiveness. Experimental results show that the proposed algorithm can detect arc fault in a timely manner and is free of nuisance trip from normal circuit operations such as load change condition. [ABSTRACT FROM AUTHOR]

Our aim was to investigate cancer department nurses' attitudes and practices in response to pelvic radiation patients' sexual issues in Sichuan, China. A self-made questionnaire survey was conducted with 150 registered nurses of six hospitals in China. Nurses were asked about their experiences regarding consultation about sexual issues and attitudes toward the sex-related statements of pelvic radiation patients. We analyzed the correlation factors for the attitudes about dealing with patients' sexual issues by using the ff-test. Of the survey sample, 128 nurses (85.33%) responded. Of the respondents, 46.88% had been consulted about sexual issues by patients or families. In addition, 87.5% of the nurses believed that 'reliable information on sexual in pelvic radiotherapy is lacking', and 77.34% reported having 'an inter-est in undertaking education of knowledge about pelvic radiation patients' sexual issues'; yet only 4.69% had completed professional sexual education about pelvic radiation patients. The hospital type and bed number as well as nurse age and seniority also affected the responses. This study shows that discussing sexuality is still repressed in the patient-nurse rela-tionship, and most nurses' in Chinese cancer departments lack knowledge about pelvic radiation patients' sextial problems. [ABSTRACT FROM AUTHOR]

The choice of the materials used as the dielectric media in large transformers continues to be a combination of pressboard and mineral oil. However, a number of failures in the field have been attributed to the surface discharge or creeping discharge over the oil/pressboard interface. This paper reports on an experiment to study surface discharge over oil/pressboard. The TJ (triple-junction) model was used to study the characteristic of partial discharge (PD) from inception to flashover. The max PD charge, pattern, frequency and current pulse were measured during the flashover process. Four oil/pressboard specimens with different aging degrees were used and their influence on the flashover process over oil/paper interface was studied in this experiment. The results indicate that the max PD charge and PD frequency increase with the increase of applied voltage. The oil aging has great influence while the pressboard aging has little influence on PD characteristic over oil/pressboard. The PD pattern and current pulse shape show great difference for various applied voltages. The results therefore suggest that the PD detection on the oil/pressboard can be used effectively to implement the early monitor of surface discharge thereby to avoid the formation of surface flashover. [ABSTRACT FROM AUTHOR]

The continuous test on oil impregnated pressboard insulation with internal void defect was developed and the phase resolved partial discharge (PRPD) pattern of partial discharge (PD) signals during the electrical aging process was measured. Two different void structures which have different void volume were used in this experiment. It shows that the PD pattern could be classified into five stages and a great diversity in the first four stages is observed. The larger void volume leads to larger PD magnitude. The computer numerical simulation model which is based on a physical discharge process was used and the causes of PD pattern change were interpreted by comparison with computer numerical simulation results. The initial values and change tendency of gas pressure and surface conductivity were determined through experiment. The model parameters in different stages have been studied as well as the insight into the physical changes in the void during electrical aging. The results provide rules for the identification of the electrical aging stage through the partial discharge measurements. [ABSTRACT FROM AUTHOR]

In postgenomic age, with the avalanche of protein sequences generated and relatively slow progress in determining their structures by experiments, it is important to develop automated methods to predict the structure of a protein from its sequence. The membrane proteins are a special group in the protein family accounts for approximately 30% of all proteins; however, solved membrane protein structures only represent less than 1% of known protein structures to date. Although a great success has been achieved for developing computational intelligence techniques to predict secondary structures in both globular and membrane proteins, there is still much challenging work in this regard. In this review article, we firstly summarize the recent progress of automation methodology development in predicting protein secondary structures, especially in membrane proteins; we will then give some future directions in this research field. [ABSTRACT FROM AUTHOR]

Objective: Cancer patients and their families differed in their attitude toward truth telling. The objective is to investigate different attitudes of Chinese patients or families toward whether and how to disclose diagnosis to patients with different stages of cancer and to examine the difference between the two groups. Methods: A questionnaire was delivered to 1023 participants. Results: Three hundred and eighty-two patients and 482 families completed the questionnaire. Cancer patients were more likely than families to believe that patient should be informed of the diagnosis (early-stage, 90.8 vs 69.9%, P<0.001; terminal stage, 60.5 vs 34.4%, P<0.001), and that doctor-in-charge was the appropriate person to disclose the diagnosis. Most participants thought that patient should be disclosed immediately after the diagnosis. Nearly half of participants reported that patient should be disclosed in a quiet and undisturbed room. When the hypothetic diagnosis changed from early-stage cancer to terminal illness, the number of participants, who wanted patient to know the diagnosis, decreased significantly. Conclusion: Our findings indicated that Chinese cancer patients and their families differed in their attitude toward truth telling and the attitudes toward such a disclosure were influenced by disease stage. Physicians should realize this phenomenon and pay more attention to the skills of how to disclose the cancer diagnosis. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome (SARS) coronavirus (SCoV) spike (S) protein is the major surface antigen of the virus and is responsible for receptor binding and the generation of neutralizing antibody. To investigate SCoV S protein, full-length and individual domains of S protein were expressed on the surface of insect cells and were characterized for cleavability and reactivity with serum samples obtained from patients during the convalescent phase of SARS. S protein could be cleaved by exogenous trypsin but not by coexpressed furin, suggesting that the protein is not normally processed during infection. Reactivity was evident by both flow cytometry and Western blot assays, but the pattern of reactivity varied according to assay and sequence of the antigen. The antibody response to SCoV S protein involves antibodies to both linear and conformational epitopes, with linear epitopes associated with the carboxyl domain and conformational epitopes associated with the amino terminal domain. Recombinant SCoV S protein appears to be a suitable antigen for the development of an efficient and sensitive diagnostic test for SARS, but our data suggest that assay format and choice of S antigen are important considerations. [ABSTRACT FROM AUTHOR]

Background: Thalassemia presents a higher incidence in southern China. The objective of this study is to analyze the genotype distribution of thalassemia in Yangjiang, a western city of Guangdong Province in China.Methods: The genotypes of suspected cases with thalassemia were tested by PCR and reverse dot blot (RDB). Unidentified rare thalassemia genotypes of the samples were further ascertained by PCR and direct DNA sequencing.Results: Among 22467 suspected cases with thalassemia, 7658 cases were found with thalassemia genotypes using our PCR-RDB kit. Among these 7658 cases, 5313 cases were found with α-thalassemia (α-thal) alone, --SEA/αα was the most common genotype, accounting for 61.75% of α-thal genotypes, and the following mutations were found: α3.7/αα, -α4.2/αα, αCSα/αα, αWSα/αα, and αQSα/αα. A total of 2032 cases were found with β-thalassemia (β-thal) alone. βCD41-42/βN, βIVS−II−654/βN, and β−28/βN accounted for 80.9% of all β-thal genotypes, and the following genotypes were found: βCD17/βN, βCD71-72/βN, and βE/βN. Compound heterozygotes of β-thal and β-thalassemia homozygotes were identified in 11 and five cases, respectively, in this study. α-thal combined with β-thal was identified in 313 cases, showing 57 genotype combinations of the coincidence of both Hb disorders; one extreme patient had a genotype of --SEA/αWSα and βCD41-42/β−28. In addition, four rare α-mutations (--THAI, HKαα, Hb Q-Thailand, and CD31 AGG>AAG) and six rare β-mutations (CD39 CAG>TAG, IVS-Ⅱ-2 (−T), −90(C>T), Chinese Gγ+(Aγδβ)0, CD104 (-G), and CD19 A>G) were also found in this study population.Conclusion: This study provided detailed genotypes of thalassemia in Yangjiang of western Guangdong Province in China and reflected the complexity of genotypes in this high-prevalence region, and this would be valuable for diagnosis and counseling for thalassemia in this area.

Magnolia sinostellata Chiu & Chen is a rare and endangered species endemic to subtropical China. Here we assembled and annotated the complete chloroplast (cp) genome of M. sinostellata. The chloroplast genome of M. sinostellata is 160,076 bp in length and encodes 79 protein-coding genes, 30 transfer RNA (tRNA) genes and four ribosomal RNA (rRNA) genes. The maximum-likelihood (ML) phylogenetic analysis result reveals that M. sinostellata is most closely related to M. biondii.

Background and Objectives: Peroral supplementation with trivalent-chromium (Cr) or magnesium (Mg) has been shown to improve insulin resistance (IR). The objective of this study was to determine whether combined peroral supplementation with Cr and Mg improves IR more effectively than Cr or Mg alone. Methods and Study Design: Subjects (n=120, age range 45-59 years old) and diagnosed with IR were randomly divided into four groups and monitored for a period of 3 months: group 1 (the placebo control group), group 2 (160 μg/d Cr), group 3 (200 mg/d Mg), and group 4 (160 μg/d Cr plus 200 mg/d Mg). Fasting blood glucose (FBG), fasting insulin (FIns), erythrocyte Cr and Mg content, and glucose-transporter-4 (GLUT4) and glycogen-synthase-kinase-3β (GSK3β) mRNA levels in activated T-lymphocytes were measured, and insulin resistant index (IRI) was calculated. Results: Significant decreases between the baseline and study conclusion values of FBG (0.37 mmol/L, p<0.01), FIns (2.91 μIU/mL, p<0.01) and IRI (0.60, p<0.01) were observed in group 4, but not groups 1-3. Similarly, compared with baseline, significant changes in GLUT4 (2.9-fold increase, p<0.05) and GSK3β (2.2-fold decrease, p<0.05) mRNA levels in activated T-lymphocyte were observed at the study's conclusion in group 4, but not in groups 1-3. Conclusions: Our results indicate that combining peroral supplementation with Cr and Mg improves IR more effectively than Cr or Mg alone, and this may be attributable to increased induction and repression, respectively, of GLUT4 and GSK3β expression. [ABSTRACT FROM AUTHOR]

Objective: Preterm birth is one of the most important health problems in the world. Feeding intolerance is one of the most common and serious complications of premature infant. The purpose of this study was to explore the effect of Chinese pediatric Tuina on the prevention of feeding intolerance in favour of weight gain in premature infants., Methods: A prospective randomized controlled study was conducted in the Department of Neonatology in our hospital. Premature infants were recruited and randomly assigned to an intervention group or a control group. Premature infants in the intervention group received a Chinese pediatric Tuina intervention by professional chiropractors, while premature infants in the control group received standard care. The incidence of feeding intolerance and weight gain situation were compared between the two groups., Result: After 1 week of intervention, the body weight (2.5±0.5 vs 2.0±0.4, p=0.038), head circumference (32.8±1.7 vs 29.9±1.4, p=0.041), albumin (34.6±5.8 vs 28.4±6.1, p-0.026) and prealbumin (155.8±35.2 vs 113.6±36.8, p=0.021) of preterm infants in the intervention group were significantly better than those in the control group. The incidence of feeding intolerance (7 vs 15, p=0.032) in the intervention group was significantly lower than that in the control group. Although there were no statistically significant differences (P>0.05), the incidences of gastrointestinal bleeding, necrotizing enterocolitis, and liver insufficiency were lower in the intervention group than in the control group., Conclusion: Chinese pediatric Tuina can effectively prevent the occurrence of feeding intolerance in premature infants and be conducive to the weight gain and improving nutritional status of premature infants., Competing Interests: The authors declare that they have no competing interests., (© 2023 Li S-S et al.)

Aim: To investigate the associations between miRNA-103 (miR-103) and insulin resistance and nonalcoholic fatty liver disease (NAFLD)., Methods: Serum samples were collected from 50 NAFLD patients who were overweight or obese (NAFLD group) and from 30 healthy subjects who served as controls (normal control group). Quantitative polymerase chain reaction was used to detect expression of miR-103. Fasting plasma glucose, fasting insulin, and triglyceride (TG) levels were measured. Homeostasis model assessment was used to evaluate basal insulin resistance (HOMA-IR). Patient height and weight were measured to calculate body mass index (BMI)., Results: Compared with the normal control group, higher serum levels of miR-103 were expressed in the NAFLD group (8.18 ± 0.73 vs 4.23 ± 0.81, P = 0.000). When P = 0.01 (bilateral), miR-103 was positively correlated with HOMA-IR (r = 0.881), TG (r = 0.774) and BMI (r = 0.878), respectively. miR-103, TG and BMI were all independent factors for HOMA-IR (β = 0.438/0.657/0.251, P = 0.000/0.007/0.001). miR-103, TG, BMI and HOMA-IR were all risk factors for NAFLD (odds ratio = 2.411/16.196/1.574/19.11, P = 0.009/0.022/0.01/0.014)., Conclusion: miR-103 is involved in insulin resistance and NAFLD, and may be a molecular link between insulin resistance and NAFLD and a therapeutic target for these disorders.