[CDK1, CCNB1 and NDC80 are associated with prognosis and progression of hepatitis B virus-associated hepatocellular carcinoma: a bioinformatic analysis]

OBJECTIVE

To identify the key genes involved in the transformation of hepatitis B virus (HBV) into hepatocellular carcinoma (HCC) and explore the underlying molecular mechanisms.

METHODS

We analyzed the mRNA microarray data of 119 HBV-related HCC tissues and 252 HBV-related non-tumor tissues in GSE55092, GSE84044 and GSE121248 from the GEO database, and the "sva" R package was used to remove the batch effects. Integration analysis was performed to identify the differentially expressed genes (DEGs) in HBV-related liver cancer and liver tissues with HBV infection. The significant DEGs were functionally annotated using GO and KEGG analyses, and the most important modules and hub genes were explored with STRING analysis. Kaplan-Meier and Oncomine databases were used to verify the HCC gene expression data in the TCGA database to explore the correlations of the hub genes with the occurrence, progression and prognosis of HCC. We also examined the expressions of the hub genes in 17 pairs of surgical specimens of HCC and adjacent tissues using RT-qPCR.

RESULTS

We identified a total of 121 DEGs and 3 genetic markers in HCC (P < 0.01). These DEGs included cyclin1 (CDK1), cyclin B1 (CCNB1), and nuclear division cycle 80 (NDC80), which participated in cell cycle, pyrimidine metabolism and DNA replication and were highly correlated (P < 0.05). Analysis of the UALCAN database confirmed high expressions of these 3 genes in HCC tissues, which were correlated with a low survival rate of the patients, as shown by Kaplan-Meier analysis of the prognostic data from the UALCAN database. CDK1, CCNB1 and NDC80 were all correlated with the clinical grading of HCC (P < 0.05). The results of RT-qPCR on the surgical specimens verified significantly higher expressions of CDK1, CCNB1 and NDC80 mRNA in HCC tissues than in the adjacent tissues.

CONCLUSION

CDK1, CCNB1 and NDC80 genes can be used as prognostic markers of HBV-related HCC and may serve as potential targets in preclinical studies and clinical treatment of HCC.

Electrochemiluminescent chiral discrimination with chiral Ag2S quantum dots/few-layer carbon nitride nanosheets

Well-dispersed chiral Ag₂S quantum dots (Ag₂S QDs) were facilely synthesized by using N-acetyl-L-cysteine (NALC) as the chiral ligand and loaded onto nanosheets of two-dimensional (2D) few-layer carbon nitride (C₃N₄). The resultant nanocomposite (Ag₂S QDs/few-layer C₃N₄) shows enhanced electrochemiluminescence (ECL) while maintaining the chirality of Ag₂S QDs, which can be used for the chiral discrimination of the enantiomers of tyrosine (Tyr). Due to the higher affinity of chiral Ag₂S QDs toward L-Tyr than toward its enantiomer, the ECL intensity of Ag₂S QDs/few-layer C₃N₄ is significantly decreased after its incubation with L-Tyr, and thus the Tyr enantiomers can be discriminated. The developed ECL chiral sensor exhibits high stability and reproducibility. The universality of the ECL chiral sensor for the discrimination of other chiral amino acids is also studied, and the results indicate that it can work only in the case of chiral aromatic amino acids.

Clinical benefits of TNF-α inhibitors in Chinese adult patients with NLRP3-associated autoinflammatory disease

BACKGROUND

Nucleotide-binding oligomerization domain-like receptor family, pyrin domain containing 3 (NLRP3)-associated autoinflammatory disease (NLRP3-AID) is a rare, heterogeneous disease entity associated with mutations in NLRP3. Biologic therapy for NLRP3-AID yields diverse results.

OBJECTIVES

We aimed to evaluate the clinical features and outcomes of Chinese adult patients with NLRP3-AID who were treated with tumour necrosis factor (TNF)-α inhibitors.

METHODS

Five patients with NLRP3-AID were diagnosed and treated with TNF-α inhibitors at Peking Union Medical College Hospital between 2017 and 2020 and were followed up for 6 to 12 months. All patients were systematically studied for treatment outcomes, including clinical manifestations and inflammatory markers.

RESULTS

All five adult NLRP3-AID patients were Chinese Han, and four patients were males. The mean age at disease onset was 4.2 ± 4.1 years, and the mean time of diagnosis delay was 19.8 ± 6 years. All patients received TNF-α inhibitors with or without methotrexate/prednisone. During follow-up, all patients achieved remarkable clinical remission of skin lesions and polyarthritis and showed improvements in acute-phase reactants, inflammatory cytokines, patient visual analogue scale, physician global assessment and 36-item Short Form (SF-36).

CONCLUSIONS

Early diagnosis and effective therapy for NLRP3-AID are essential for avoiding irreversible organ damage. TNF-α inhibitors might serve as a therapeutic alternative for patients with NLRP3-AID who have unsatisfactory responses or no access to interleukin-1 inhibitors.

Correlation between culprit vessel/tirofiban and reperfusion bradyarrhythmia in patients with ST-segment elevation myocardial infarction after emergency PCI

OBJECTIVE

To evaluate the correlation between culprit vessel/tirofiban and reperfusion bradyarrhythmia in patients with ST-segment elevation myocardial infarction (STEMI) after emergency percutaneous coronary intervention (PCI).

PATIENTS AND METHODS

A total of 123 STEMI patients undergoing emergency PCI in our hospital from September 2018 to September 2019 were selected and divided into the reperfusion arrhythmias (RA) group (50 cases) and non-RA group (NRA, 73 cases) according to whether RA occurring during PCI. The baseline data such as age and underlying disease were statistically analyzed. Then, the differences were compared between the two groups. According to whether reperfusion bradyarrhythmia (RB) occurring during PCI, 123 STEMI patients were divided into the RB group (63 cases) and non-RB group (60 cases). The relation between culprit vessel/tirofiban and RB was analyzed. ROC curves analysis and multivariate logistic regression were conducted for the risk factors of RA and RB.

RESULTS

Among 123 patients with STEMI after PCI treatment, 73 patients had RA (59.35%), including RB 63 cases and tachyarrhythmia 10 cases. Results of single factor analysis showed that there was statistical significance in 3 factors including the patient age, infarction area and vascular blood flow TIMI classification between RA group and NRA group (p<0.05). ROC curve analysis indicated that the continuous variable patent ages had predictive value in the prevalence of RA, which resulting in an AUC 0.624 and a cut-off pointed age 57 (sensitivity 72.60, specificity 52.00). Multivariate regression analysis showed that the patient age (>57 years old), infarction area in inferior wall and grade 0 lesion vascular blood flow TIMI classification in RA group was significantly higher than that in NRA group (p<0.05). Tirofiban was not associated with RB in STEMI patients treated with emergency PCI, while culprit vessel was statistically significant between RB group and NRB group (p<0.05). Multivariate regression analysis indicated that culprit vessel of the right coronary artery and grade 0 lesions vascular blood flowed TIMI classification was independent risk factors to occurring RB in the STEMI patients with emergency PCI.

CONCLUSIONS

Tirofiban was not associated with RB in STEMI patients treated with emergency PCI. However, it may increase the risk of RB development when the culprit vessel is the right coronary artery. Therefore, timely corresponding treatments and reduction of reperfusion damage are of great significance for those patients.

A novel micro-tensile system for full-field deformation measurement of thin films

We propose a novel micro-tensile system fit for mechanical property characterization of low-dimensional materials. The micro-tensile system was integrated with a micro-tensile apparatus driven by a piezoelectric transducer (PZT) and an optical microscope. The displacement provided by the PZT actuator was amplified by a lever structure on the micro-tensile apparatus. A stalloy was designed to transmit the displacement and reduce the mechanical resistance to the PZT actuator. Quantitative analysis was conducted for the designed apparatus. A calibration experiment was performed based on the micro-scale digital image correlation under the optical microscope. To validate the feasibility, the PET film specimen with a V-notch was tested by the proposed system. The results indicate that the proposed micro-tensile system is reliable and powerful.

[Evaluation on applicationof virtual reality technology in dental implant process training]

Objective: To explore the application effect and evaluation of virtual reality technology in oral implant therapy training. Methods: In November 2018, one adult patient (female, 36 years old) with missing right mandibular first molar was treated in the Department of Implantology, School and Hospital of Stomatology, Fujian Medical University. The three-dimensional virtual models of mandible and implant surgery tools were established, and the virtual reality software (Unity 3D 5.5.1) was imported. Combined with the virtual reality head mounted display, a virtual reality training system simulating the dental implant treatment process was independently developed. Ten refresher doctors and 20 graduate students in Department of Implantology, School and Hospital of Stomatology, Fujian Medical University from September 2018 to December 2019 were recruited as the experimental objects (no clinical experience was found). According to the level and seniority of doctors, they were randomly divided into virtual training group and conventional training control group, which made the two groups comparable, with 15 in each group. Subjective scores (including anatomical structure, surgical field of vision, cavity preparation, implant placement and process mastery) were given after the corresponding training in the two groups, and the virtual reality training system was used to test. The mesial and distal direction, buccolingual direction, depth and angle deviation of implants before and after the training were analyzed, and the differences between the two groups were compared. Results: The subjective scores of five dimensions in the virtual training group were significantly higher than those in the conventional training control group (P<0.05). In the virtual training group, the mesial and distal, buccolingual, depth and angle deviation of implants were (0.73±0.33), (0.78±0.41), (0.61±0.32) mm and 6.66°±3.87°. All of them were significantly lower than those in the control group [(0.85±0.32), (1.12±0.38), (0.89±0.24) mm and 9.68°±3.74°] (P<0.05). Conclusions: The self-developed virtual reality system of oral implant has good application effect, good operability and predictability. It can be effectively carried out in implant education and training, and it can strengthen skills of doctors, and is conducive to the practical operation.

[Genetic and clinical analysis of X-linked hypophosphatemic rickets]

Objective: To investigate the clinical and genetic features, and treatment of X-linked hypophosphatemic rickets (XLH). Methods: In this retrospective study, we reviewed the medical records of 25 pediatric patients with XLH who were admitted to Department of Endocrinology Genetics and Metabolism,Beijing Children's Hospital from January 2010 to January 2020. The clinical characteristics, PHEX gene variants, as well as clinical outcome of the patients were summarized. To analyze the correlation between genotype and phenotype, the patients were divided into different subgroups according to the location of the variants, including N-terminal-located vs. C-terminal-located variant, and Zn-binding domain exon 17 or 19 variant vs. non-exon 17 or 19 variant. The age at onset, height standard deviation score (HtSDS), intercondylar or intermalleolar distance, fasting serum phosphorus, and HtSDS and intercondylar or intermalleolar distance at the final follow-up were compared by rank sum test or t text. Results: Among the 25 children with XLH, 8 were boys and 17 were girls. The median age of onset was 1.2 (1.0, 1.8) years, and the median age of diagnosis was 2.5 (1.5, 4.3) years. The main clinical manifestations were abnormal gait and lower limb deformity. The HtSDS was -2.0(-3.2, -0.8), and the intercondylar or intermalleolar distance was 4.5 (3.0, 6.0) cm. The fasting serum phosphorus level was 0.8 (0.7, 0.9) mmol/L, while the serum alkaline phosphatase level was (721±41) U/L and the serum calcium level was (2.5±0.1) mmol/L. Three patients (12%) had parathyroid hormone levels above the upper limit of the normal range. Twenty-five patients (100%) showed radiographic changes of active rickets. Nephrocalcinosis was found in 2 cases (9%). Twenty-four different PHEX variations were detected in 25 patients, among whom 11 (44%) had not been reported previously. No hot spot variation was found. No statistical differences (all P>0.05) were identified in clinical features and outcomes either in comparing patients with N-terminal (21 cases) and C-terminal (4 cases) variants, or in comparing patients with variant located in exon 17 or 19 (4 cases) or not (21 cases). Twenty-four cases (96%) were treated regularly with phosphate supplements and active vitamin D. After 2.7 (1.6, 5.0) years of follow-up, clinical symptoms were relieved in 96% (24/25) of the patients. The HtSDS after treatment had no significant difference compared to that before treatment (-2.0(-3.2, -0.8) vs.-2.0(-2.8, -1.1),Z =-0.156, P>0.05), while the intercondylar or intermalleolar distance after treatment was significantly reduced compared to that before treatment (4.5(3.0, 6.0) vs. 1.5(0, 3.3) cm, Z =-3.043, P<0.05). Bone X-rays were reexamined in 17 cases after treatment, and radiographic signs of rickets were improved. Eighteen cases had secondary hyperparathyroidism and 7 cases had nephrocalcinosis. Conclusions: The main clinical manifestations of XLH are abnormal gait, lower limb deformity and short stature. A high proportion of novel variations of PHEX gene but no hot spot variation neither genotype-phenotype correlation are found. Regular treatment with phosphate supplements and active vitamin D can significantly improve the symptoms except for the height. However, the rate of adverse events including secondary hyperparathyroidism and nephrocalcinosis seems to be high.

[Surveillance of human soil-transmitted nematodiasis in Jurong City from 2016 to 2020]

OBJECTIVE

To investigate the prevalence of soil-transmitted nematode human infections in Jurong City from 2016 to 2020, so as to provide the scientific evidence for formulating the control strategy.

METHODS

During the period from 2016 to 2020, the permanent residents at ages of over 3 years living in Jurong City were selected as the study subjects. Stool samples were collected for the detection of soil-transmitted nematode eggs using the modified Kato-Katz thick smear method (two detections for one stool sample), and the species of hookworm was identified in stool-positive stool samples using the culture method. The prevalence and intensity of soil-transmitted nematode infections were calculated, and the change of the infection prevalence among years was examined using the Cochran-Armitage test for trend.

RESULTS

A total of 10 011 people-time populations were detected for soil-transmitted nematode infections in Jurong City from 2016 to 2020, and 56 egg-positives were identified, with mean prevalence of 0.56%. The prevalence of soil-transmitted nematode human infections appeared a tendency towards a decline year by year in Jurong City (χ²_trend = 5.15, P < 0.01). The mean prevalence of hookworm, Ascaris lumbricoides and Trichuris trichiura infections was 0.44%, 0.11% and 0.20% in Jurong City from 2016 to 2020, respectively, and individuals with hookworm infections accounted for 78.57% of all cases with soil-transmitted nematode infections. Single parasite (98.21%) and mild infection were pre-dominant in individuals with soil-transmitted nematode infections, and no multiple infections were seen after 2016.

CONCLUSIONS

The prevalence of human soil-transmitted nematodiasis is low in Jurong City. Based on reinforcement of soil-transmitted nematodiasis surveillance, an increase in the health education investment is required to consolidate the control achievements.

Strategies to Achieve a Ferrocene-Based Polymer with Reversible Redox Activity for Chiral Electroanalysis of Nonelectroactive Amino Acids

In the past, various chiral isomers accompanied by electroactive units have been distinguished using electrochemical techniques, which can produce electrochemical signals by themselves. However, it is still difficult to use an electrochemical technique to detect nonelectroactive samples. To address this bottleneck, an electroactive chiral polymer (S,S)-p-CVB-Fc that contains one redox-active ferrocene unit was designed and synthesized in this study. The electroactive polymer can give electrochemical signals as an alternative to the tested chiral samples, regardless of whether the isomers have electroactive units. Then, it was fixed on the surface of a glassy carbon electrode as an electrochemical chiral sensor. When nonelectroactive amino acids including proline, threonine, and alanine were examined by the sensor, clear discrimination in the response of peak current could be observed toward l- and d-isomers at pH 6.5. The peak current ratios (I_L/I_D) for proline and alanine were 1.47 and 1.48, respectively. In contrast, for threonine, the d-isomer exhibited a higher peak current than the l -isomer with a ratio of 2.59. In summary, the results ensure that the current work can enlarge the testing scope of chiral samples in the field of chiral electroanalysis using an electroactive sensor.

Long non-coding RNA PLAC2 suppresses the survival of gastric cancer cells through down-regulating C-Myc

OBJECTIVE

The aim of this study was to explore the effects of long non-coding ribonucleic acid (lncRNA) placenta-specific protein 2 (PLAC2) on the biological behaviors of gastric cancer (GC) cells by regulating the expression of c-Myc gene and its mechanism.

PATIENTS AND METHODS

The expression of PLAC2 in GC tissues and different GC cell lines was detected via quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR). The effects of PLAC2 on apoptosis and cycle, migration, and invasion of GC cells were detected using flow cytometry, wound healing assay, and transwell assay, respectively. After interference in PLAC2 expression, the changes in c-Myc expression were determined through qRT-PCR and Western blotting.

RESULTS

The expression level of PLAC2 was downregulated in 38 out of 45 cases of GC tissues compared with that in normal gastric tissues, and it also declined in GC cells. The results of flow cytometry showed that after overexpression of PLAC2, the cell cycle was arrested in the G1/G0 phase, and the apoptosis rate was increased. The results of wound healing assay and transwell assay revealed that both migration and invasion of GC cells were inhibited. After overexpression of PLAC2, the mRNA and protein expression levels of c-Myc declined.

CONCLUSIONS

LncRNA PLAC2 affects the biological behaviors of GC cells by regulating the expression of c-Myc gene.

Recent advances of the ionic chiral selectors for chiral resolution by chromatography, spectroscopy and electrochemistry

Ionic chiral selectors have been received much attention in the field of asymmetric catalysis, chiral recognition, and preparative separation. It has been shown that the addition of ionic chiral selectors can enhance the recognition efficiency dramatically due to the presence of multiple intermolecular interactions, including hydrogen bond, π-π interaction, van der Waals force, electrostatic ion-pairing interaction, and ionic-hydrogen bond. In the initial research stage of the ionic chiral selectors, most of work center on the application in chromatographic separation (capillary electrophoresis, high-performance liquid chromatography, and gas chromatography). Differently, more and more attention has been paid on the spectroscopy (nuclear magnetic resonance, fluorescence, ultraviolet and visible absorption spectrum, and circular dichroism spectrum) and electrochemistry in recent years. In this tutorial review as regards the ionic chiral selectors, we discuss in detail the structural features, properties, and their application in chromatography, spectroscopy, and electrochemistry.

Fluorometric discrimination of tyrosine isomers based on the inner filter effect of chiral Au nanoparticles on MoS2 quantum dots

A fluorescent chiral sensor is proposed based on the inner filter effect (IFE) of chiral Au nanoparticles (AuNPs) on MoS2 quantum dots (MoS2 QDs), which can be used for the discrimination of the isomers of tyrosine (Tyr). l-Tyrosine (l-Tyr) can induce obvious agglomeration of the chiral AuNPs, leading to an attenuated IFE of the chiral AuNPs and greatly restored fluorescence of the MoS2 QDs, and thus the enantioselective recognition of the Tyr isomers can be achieved. Also, l-Tyr but not d-Tyr induced agglomeration of the chiral AuNPs is confirmed by the larger association constant between l-Tyr and the chiral sensor.

Measurement of the Cosmic Ray Helium Energy Spectrum from 70 GeV to 80 TeV with the DAMPE Space Mission

The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the Dark Matter Particle Explorer (DAMPE) is reported in this work. A hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of 4.3σ. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out.

[A multi-center retrospective study of perioperative chemotherapy for gastric cancer based on real-world data]

Objective: To explore the effect of perioperative chemotherapy on the prognosis of gastric cancer patients under real-world condition. Methods: A retrospective cohort study was carried out. Real world data of gastric cancer patients receiving perioperative chemotherapy and surgery + adjuvant chemotherapy in 33 domestic hospitals from January 1, 2014 to January 31, 2016 were collected. Inclusion criteria: (1) gastric adenocarcinoma was confirmed by histopathology, and clinical stage was cT2-4aN0-3M0 (AJCC 8th edition); (2) D2 radical gastric cancer surgery was performed; (3) at least one cycle of neoadjuvant chemotherapy (NAC) was completed; (4) at least 4 cycles of adjuvant chemotherapy (AC) [SOX (S-1+oxaliplatin) or CapeOX (capecitabine + oxaliplatin)] were completed. Exclusion criteria: (1) complicated with other malignant tumors; (2) radiotherapy received; (3) patients with incomplete data. The enrolled patients who received neoadjuvant chemotherapy and adjuvant chemotherapy were included in the perioperative chemotherapy group, and those who received only postoperative adjuvant chemotherapy were included in the surgery + adjuvant chemotherapy group. Propensity score matching (PSM) method was used to control selection bias. The primary outcome were overall survival (OS) and progression-free survival (PFS) after PSM. OS was defined as the time from the first neoadjuvant chemotherapy (operation + adjuvant chemotherapy group: from the date of operation) to the last effective follow-up or death. PFS was defined as the time from the first neoadjuvant chemotherapy (operation + adjuvant chemotherapy group: from the date of operation) to the first imaging diagnosis of tumor progression or death. The Kaplan-Meier method was used to estimate the survival rate, and the Cox proportional hazards model was used to evaluate the independent effect of perioperative chemo therapy on OS and PFS. Results: 2 045 cases were included, including 1 293 cases in the surgery+adjuvant chemotherapy group and 752 cases in the perioperative chemotherapy group. After PSM, 492 pairs were included in the analysis. There were no statistically significant differences in gender, age, body mass index, tumor stage before treatment, and tumor location between the two groups (all P>0.05). Compared with the surgery + adjuvant chemotherapy group, patients in the perioperative chemotherapy group had higher proportion of total gastrectomy (χ(2)=40.526, P<0.001), smaller maximum tumor diameter (t=3.969, P<0.001), less number of metastatic lymph nodes (t=1.343, P<0.001), lower ratio of vessel invasion (χ(2)=11.897, P=0.001) and nerve invasion (χ(2)=12.338, P<0.001). In the perioperative chemotherapy group and surgery + adjuvant chemotherapy group, 24 cases (4.9%) and 17 cases (3.4%) developed postoperative complications, respectively, and no significant difference was found between two groups (χ(2)=0.815, P=0.367). The median OS of the perioperative chemotherapy group was longer than that of the surgery + adjuvant chemotherapy group (65 months vs. 45 months, HR: 0.74, 95% CI: 0.62-0.89, P=0.001); the median PFS of the perioperative chemotherapy group was also longer than that of the surgery+adjuvant chemotherapy group (56 months vs. 36 months, HR=0.72, 95% CI:0.61-0.85, P<0.001). The forest plot results of subgroup analysis showed that both men and women could benefit from perioperative chemotherapy (all P<0.05); patients over 45 years of age (P<0.05) and with normal body mass (P<0.01) could benefit significantly; patients with cTNM stage II and III presented a trend of benefit or could benefit significantly (P<0.05); patients with signet ring cell carcinoma benefited little (P>0.05); tumors in the gastric body and gastric antrum benefited more significantly (P<0.05). Conclusion: Perioperative chemotherapy can improve the prognosis of gastric cancer patients.

THz-TDS Reflection Measurement of Coating Thicknesses at Non-Perpendicular Incidence: Experiment and Simulation

Time-domain spectroscopy (TDS) in the terahertz (THz) frequency range is gaining in importance in nondestructive testing of dielectric materials. One application is the layer thickness measurement of a coating layer. To determine the thickness from the measurement data, the refractive index of the coating layer must be known in the surveyed frequency range. For perpendicular incidence of the radiation, methods exist to extract the refractive index from the measurement data themselves without prior knowledge. This paper extends these methods for non-perpendicular incidence, where the polarization of the radiation becomes important. Furthermore, modifications considering effects of surface roughness of the coating are introduced. The new methods are verified using measurement data of a sample of Inconel steel coated with yttria-stabilized zirconia (YSZ) and with COMSOL simulations of the measurement setup. To validate the thickness measurements, scanning electron microscopy (SEM) images of the layer structure are used. The results show good agreement with an average error of 1% for the simulation data and under 4% for the experimental data compared to reference measurements.

[Molecular-related epidemic characteristics of influenza A (H3N2) viruses in Guangzhou, 2019]

Objective: To isolate the influenza A (H3N2) viruses from different sources in Guangzhou in 2019 and analyze these viruses' evolution and variation characteristics. Methods: The hemagglutinin (HA) and neuraminidase (NA) genes of H3N2 isolates from outpatient monitoring, influenza outbreaks, and inpatient severe cases in Guangzhou in 2019 were sequenced. Bioinformatics software analyzed the variations and evolution characteristics of HA and NA genes. Results: The epidemic peaks of influenza A (H3N2) viruses were made up of period Ⅰ (from January to August) and period Ⅱ (from November to December). The positive rate of influenza A (H3N2) in males was 13.46% (703/5 221), which was higher than that in females (11.50%, 510/4 435) (χ²=8.43,P=0.00). The group's positive rate of 10-20 years old was the highest (25.18%,665/2 641). The isolates from different sources were highly homologous and closely related to 3C.2a.1 branches, which could be further divided into three small groups of Group 1-3. Gene recombination was observed between different branches. The mutations of HA antigen sites gradually appeared from Group 1 to Group 3, leading to new antigen drift. Variations of HA antigenic sites mainly occurred in the region of A and B. The mutations of receptor binding sites of Group 1 and Group 3 viruses occurred in the anterior and posterior walls. There were two glycosylation sites lacked on region A of HA antigen observed in the isolates of Group 2-3. Conclusions: Genetic variations of H3N2 influenza viruses in Guangzhou included gene mutations and gene recombination. Under the pressure of the vaccine, the evolution of viruses was rapid. Therefore, the monitoring of molecular-related epidemic characteristics of the H3N2 influenza virus was necessary.

Nanowired NiMoO4/NiSe2/MoSe2 prepared through in situ selenylation as a high performance supercapacitor electrode

After in situ selenylation, hydrothermally synthesized NiMoO4 was partially converted to NiSe2 and MoSe2, and the obtained NiMoO4/NiSe2/MoSe2 nanowires were used as a supercapacitor electrode material. The specific capacitance of the nanowired NiMoO4/NiSe2/MoSe2 was significantly higher than that of NiMoO4 at a current density of 1 A g-1 (955 vs. 489 F g-1). NiMoO4/NiSe2/MoSe2 also exhibited a high capacitance retention of 86.1% after 5000 cycles at 10 A g-1. The high supercapacitive performance of NiMoO4/NiSe2/MoSe2 can be ascribed to the obvious heterointerfaces, rich defects and remarkably increased electrical conductivity after in situ selenylation of NiMoO4.

Kinetic study of quantum two-stream instability by Wigner approach

Classical plasma are typically of low density and/or high temperature. Two of its basic properties are Landau damping and two-stream instabilities. When increasing the plasma density, quantum effects appear and beam-plasma interactions show behavior different from the classical cases. We revisit Landau damping and two-stream instabilities under conditions when quantum hydrodynamic and quantum kinetic theory can be applied, the latter accounting for wave-particle interactions. We find that the instability growth rate behaves as pure two-stream instability without Landau damping when the countering stream velocity exceeds a certain threshold, which differs from the classical case.

Circ_0032627 accelerates proliferation of gastric cancer cells through regulating miR-502-5p expression

OBJECTIVE

To explore the biological functions of circ_0032627 in the progression of gastric cancer (GC).

MATERIALS AND METHODS

The expression level of circ_0032627 in GC cell lines and gastric mucosal cell lines was measured via quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR). Methyl thiazolyl tetrazolium (MTT) assay, colony formation assay, and FACS were performed to examine the influences of circ_0032627 on the proliferation and apoptosis of GC cells. The relationship between circ_0032627 and micro ribonucleic acids (miRNAs) was predicted on-line using StarBase software, and whether circ_0032627 can act as the sponge of the selected miRNAs was verified via Dual-Luciferase reporter assay and qRT-PCR. Finally, MTT assay was conducted to detect the influences of the co-knockdown of circ_0032627 and the selected miRNAs on the proliferation of GC cells.

RESULTS

Compared with that in gastric mucosal cell lines, the expression level of circ_0032627 was upregulated in the selected four GC cell lines, and circ_0032627 knockdown substantially inhibited the proliferation of GC cells, but promoted their apoptosis. Circ_0032627 could act as a sponge of miR-502-5p, and miR-502-3p knockdown reversed the inhibitory effect of circ_0032627 on the proliferation of GC cells.

CONCLUSIONS

The expression level of circ_0032627 is raised in GC cells, and circ_0032627 affects the proliferation and apoptosis of GC cells by sponging miR-502-5p.

Photoinduced multistage phase transitions in Ta2NiSe5

Ultrafast control of material physical properties represents a rapidly developing field in condensed matter physics. Yet, accessing the long-lived photoinduced electronic states is still in its early stages, especially with respect to an insulator to metal phase transition. Here, by combining transport measurement with ultrashort photoexcitation and coherent phonon spectroscopy, we report on photoinduced multistage phase transitions in Ta2NiSe5. Upon excitation by weak pulse intensity, the system is triggered to a short-lived state accompanied by a structural change. Further increasing the excitation intensity beyond a threshold, a photoinduced steady new state is achieved where the resistivity drops by more than four orders at temperature 50 K. This new state is thermally stable up to at least 350 K and exhibits a lattice structure different from any of the thermally accessible equilibrium states. Transmission electron microscopy reveals an in-chain Ta atom displacement in the photoinduced new structure phase. We also found that nano-sheet samples with the thickness less than the optical penetration depth are required for attaining a complete transition.