Octahedral Distortion and Displacement-Type Ferroelectricity with Switchable Photovoltaic Effect in a 3d

Because of the half-filled t_{2g}-electron configuration, the BO_{6} octahedral distortion in a 3d^{3} perovskite system is usually very limited. In this Letter, a perovskitelike oxide Hg_{0.75}Pb_{0.25}MnO_{3} (HPMO) with a 3d^{3} Mn^{4+} state was synthesized by using high pressure and high temperature methods. This compound exhibits an unusually large octahedral distortion enhanced by approximately 2 orders of magnitude compared with that observed in other 3d^{3} perovskite systems like RCr^{3+}O_{3} (R=rare earth). Essentially different from centrosymmetric HgMnO_{3} and PbMnO_{3}, the A-site doped HPMO presents a polar crystal structure with the space group Ama2 and a substantial spontaneous electric polarization (26.5 µC/cm^{2} in theory) arising from the off-center displacements of A- and B-site ions. More interestingly, a prominent net photocurrent and switchable photovoltaic effect with a sustainable photoresponse were observed in the current polycrystalline HPMO. This Letter provides an exceptional d^{3} material system which shows unusually large octahedral distortion and displacement-type ferroelectricity violating the "d^{0}-ness" rule.

[The relationship between the expression of amplified in breast cancer 1、androgen receptor and tamoxifen resistance in breast cancer].

Objective: To discuss the value of amplified in breast cancer 1(AIB1) and androgen receptor (AR) for the resistance of adjuvant tamoxifen in estradiol receptor (ER) positive breast cancer. Methods: A total of 188 cases with breast cancer after receiving tamoxifen treatment in the Tianjin Medical University Cancer Institute and Hospital from June 2008 to July 2013 were enrolled in this study.Using immunohistochemical SP method to detect AIB1and AR expression in breast cancer tissue, analyzing the relationship of AIB1 and AR expression and the effect of tamoxifen.And verify the results of the experiment through the GEPIA database. Results: The response of tamoxifen was 80.3%. The response rate in AR positive group and AR negative group was 79.6% and 82.4%, with no significant difference (P=0.669). The response rate in AIB1 High expression group and AIB1 Low expression group was 68.4% and 93.3%, respectively, with a significant difference (P<0.001).The response rate in AR negative and AIB1 Low expression group, AR negative and AIB1 High expression group, AR positive and AIB1 Low expression group, AR positive and AIB1High expression group was 89.7%, 71.4%, 96.7%, 66.2%respectively, with a significant difference (P<0.001). Conclusions: The expression level of AIB1 is correlated with the therapeutic effect of tamoxifen in breast cancer. Its high expression can cause tamoxifen resistance, while AR positive and High expression of AIB1 are more likely to cause tamoxifen resistance, and AIB1 can be used as an independent influencing factor for breast cancer tamoxifentreatment.

[Recompensation of complications in patients with hepatitis B virus-related decompensated cirrhosis treated with entecavir antiviral therapy].

Objective: To analyze the occurrence of recompensation conditions in patients with chronic hepatitis B virus-related decompensated cirrhosis after entecavir antiviral therapy. Methods: Patients with hepatitis B virus-related decompensated cirrhosis with ascites as the initial manifestation were prospectively enrolled. Patients who received entecavir treatment for 120 weeks and were followed up every 24 weeks (including clinical endpoint events, hematological and imaging indicators, and others) were calculated for recompensation rates according to the Baveno VII criteria. Measurement data were compared using the Student t-test or Mann-Whitney U test between groups. Categorical data were compared by the χ (2) test or Fisher's exact probability method between groups. Results: 283 of the 320 enrolled cases completed the 120-week follow-up, and 92.2% (261/283) achieved a virological response (HBV DNA 20 IU/ml). Child-Pugh and MELD scores were significantly improved after treatment (8.33 ± 1.90 vs. 5.77 ± 1.37, t = 12.70, P < 0.001; 13.37 ± 4.44 vs. 10.45 ± 4.58, t = 5.963, P < 0.001). During the 120-week follow-up period, 14 cases died, two received liver transplants, 19 developed hepatocellular cancer, 11 developed gastroesophageal variceal bleeding, and four developed hepatic encephalopathy. 60.4% (171/283) (no decompensation events occurred for 12 months) and 56.2% (159/283) (no decompensation events occurred for 12 months and improved liver function) of the patients had achieved clinical recompensation within 120 weeks. Patients with baseline MELD scores > 15 after active antiviral therapy achieved higher recompensation than patients with baseline MELD scores ≤15 [50/74 (67.6%) vs. 109/209 (52.2%), χ (2) = 5.275, P = 0.029]. Conclusion: Antiviral therapy can significantly improve the prognosis of patients with hepatitis B virus-related decompensated cirrhosis. The majority of patients (56.2%) had achieved recompensation. Patients with severe disease did not have a lower probability of recompensation at baseline than other patients.

[Analysis of chromosome aberrations in peripheral blood lymphocyte of medical radiation workers in a tertiary hospital].

Objective: To analyze the level of chromosome aberration in lymphocytes of medical radiation workers and its influencing factors. Methods: From July to September 2020, 252 medical workers in a tertiary hospital were selected as the study subjects and 107 preserviceworkers were selected as the control group. The Chromosomal aberrations of peripheral blood lymphocytes were measured using conventional cytogenetic analysis method, and the differences were analyzed. Results: The frequencies of dicentric puls centric ring, total chromosome-type aberrations, and abnormal detection rate in the radiation group were significantly higher than those in the control group (Z=2.59, 3.74, 9.99, P<0.05). There was significant difference in the frequencies of dicentric plus centric ring and total chromosome-type aberrations among different types of work (χ(2)=8.59, 8.17, 11.39, P<0.05), and the frequencies of dicentric plus centric ring were significantly higher in the interventional radiology group than those in diagnostic radiology (χ(2)=2.90, P<0.05), While the rates of acentric fragment and total chromosome-type aberrations were significantly higher in the nuclear medicine group than those in diagnostic radiology (χ(2)=2.81, 3.19, P<0.05). The difference in the abnormal detection rate of chromosome aberrations between different types of work was statistically significant (P<0.05), and the rate in the interventional radiology group was significantly higher than that in the diagnostic radiology group (χ(2)=7.66, P<0.05). There was no significant difference in chromosome aberration level and abnormal detection rate among different working ages (P>0.05). Poisson regression analysis indicated that the type of work is a risk factor for chromosomal aberration [IRR=2.31 (nuclear medicine group), 1.66 (Radiation therapy), and 1.78 (interventional group) ; P<0.05]. Conclusion: Ionizing radiation causes certain radiation damage to medical radiology workers, and the frequencies of chromosome aberration in the radiation workers of nuclear medicine and interventional radiology groups are relatively high, so radiation protection should be strengthened to ensure the health of relevant workers.

[Study on 4 cases of mushroom poisoning with amanita and identification of poison].

Different kinds of poisonous mushrooms contain different toxic components. Acute liver injury caused by amanita mushroom is the main cause of death from poisonous mushroom poisoning in China. Consumption of poisonous mushrooms has an incubation period, there is a false recovery period in the clinical process, and the early performance is slight and does not attract enough attention from doctors, and it is easy to miss the treatment opportunity. The clinical characteristics, treatment and identification of mushrooms containing amanita in 4 patients were analyzed in order to improve clinicians' understanding of the diagnosis and treatment of mushroom poisoning and early species identification.

Primary hyperphosphatemic tumoral calcinosis: a case report.

Tumoral calcinosis (TC) is a rare disease characterized by periarticular soft tissue calcification. Some cases were reported in Africa and the Middle East. We report an 11-year-old Chinese girl presenting with recurrent multiple subcutaneous masses around the right elbow and hip regions. Although we found abnormalities in FGF23, a protein associated with phosphate metabolism, no positive results were observed in gene sequencing and analysis. The imaging features, laboratory examination, and pathology results confirmed our diagnosis. By using oral phosphorus-lowering drugs (acetazolamide) combined with complete surgical excision, good results were achieved, and no recurrence was reported during the follow-up of 18 months. We report a case of primary hyperphosphatemic TC. The combined use of oral phosphorus-lowering drugs (acetazolamide) and complete surgical excision produced good results, and no recurrence was reported during the follow-up of 18 months.

iTRAQ-based quantitative proteomics reveals biomarkers/pathways in psoriasis that can predict the efficacy of methotrexate.

BACKGROUND: Methotrexate (MTX) is the first-line medicine to treat psoriasis. So far, there has been less research on protein biomarkers to predict its efficacy by the proteomic technique. OBJECTIVES: To evaluate differentially expressed proteins in peripheral mononuclear cells (PBMCs) between good responders (GRs) and non-responders (NRs) after MTX treatment, compared with normal controls (NCs). METHODS: We quantified protein expression of PBMCs with four GRs and four NRs to MTX and four NCs by isobaric tags for relative and absolute quantification (iTRAQ), analysing and identifying proteins related to efficacy of MTX in 18 psoriatic patients. RESULTS: A total of 3177 proteins had quantitative information, and 403 differentially expressed proteins (fold change ≥1.2, P < 0.05) were identified. Compared to NCs, upregulated proteins (ANXA6, RPS27A, EZR, XRCC6), participating in the activation of NF-κB, the JAK-STAT pathway and neutrophil degranulation were detected in GRs. The proteins (GPV, FN1, STOM), involving platelet activation, signalling and aggregation as well as neutrophil degranulation were significantly downregulated in GRs. These proteins returned to normal levels after MTX treatment. Furthermore, Western blotting identified the expression of ANXA6 and STAT1 in PBMCs, which were significantly downregulated in GRs, but not in NRs. CONCLUSIONS: We identified seven differentially expressed and regulated proteins (ANXA6, GPV, FN1, XRCC6, STOM, RPS27A and EZR) as biomarkers to predict MTX efficacy in NF-κB signalling, JAK-STAT pathways, neutrophil degranulation, platelet activation, signalling and aggregation.

[Impact of bicuspid aortic valve or tricuspid aortic valve on hemodynamics and left ventricular reverse remodeling in patients after transcatheter aortic valve replacement].

Objective: To compare the impact of bicuspid aortic valve (BAV) or tricuspid aortic valve (TAV) on hemodynamics and left ventricular reverse remodeling after transcatheter aortic valve replacement (TAVR). Methods: We retrospectively analyzed the clinical data of patients who underwent TAVR in our hospital from January 2019 to March 2021. Patients were divided into BAV group and TAV group according to aortic contrast-enhanced CT. Each patient was followed up by N-terminal pro B-type natriuretic peptide (NT-proBNP) and echocardiography at four time points, namely before TAVR, 24 hours, 1 month and 6 months after TAVR. Echocardiographic data, including mean pressure gradient (MPG), aortic valve area (AVA), left ventricular ejection fraction (LVEF), left ventricle mass (LVM) and LV mass index (LVMi) were evaluated. Results: A total of 41 patients were included. The age was (75.0±8.6) years, and male patients accounted for 53.7%. There were 19 BAV patients and 22 TAV patients in this cohort. All patients undergoing TAVR using a self-expandable prosthesis Venus-A valve. MPG was (54.16±21.22) mmHg(1 mmHg=0.133 kPa) before TAVR, (21.11±9.04) mmHg at 24 hours after TAVR, (18.84±7.37) mmHg at 1 month after TAVR, (17.68±6.04) mmHg at 6 months after TAVR in BAV group. LVEF was (50.42±13.30)% before TAVR, (53.84±10.59)% at 24 hours after TAVR, (55.68±8.71)% at 1 month after TAVR and (57.42±7.78)% at 6 months after TAVR in BAV group. MPG and LVEF substantially improved at each time point after operation, and the difference was statistically significant (all P<0.05) in BAV group. MPG in TAV group improved at each time point after operation, and the difference was statistically significant (all P<0.05). LVMi was (164.13±49.53), (156.37±39.11), (146.65±38.84) and (134.13±39.83) g/m2 at the 4 time points and the value was significantly reduced at 1 and 6 months post TAVR compared to preoperative level(both P<0.05). LVEF in the TAV group remained unchanged at 24 hours after operation, but it was improved at 1 month and 6 months after operation, and the difference was statistically significant (all P<0.05). LVMi in TAV group substantially improved at each time point after operation, and the difference was statistically significant (all P<0.05). NT-proBNP in both two groups improved after operation, at 1 month and 6 months after operation, and the difference was statistically significant (all P<0.05). MPG in TAV group improved better than in BAV group during the postoperative follow-up (24 hours after TAVR: (11.68±5.09) mmHg vs. (21.11±9.04) mmHg, P<0.001, 1 month after TAVR: (10.82±3.71) mmHg vs. (18.84±7.37) mmHg, P<0.001, 6 months after TAVR: (12.36±4.42) mmHg vs. (17.68±6.04) mmHg, P=0.003). There was no significant difference in NT-proBNP between BAV group and TAV group at each time point after operation (all P>0.05). There was no significant difference in paravalvular regurgitation and second prosthesis implantation between the two groups (all P>0.05). Conclusions: AS patients with BAV or TAV experience hemodynamic improvement and obvious left ventricular reverse remodeling after TAVR, and the therapeutic effects of TAVR are similar between BAV and TAV AS patients in the short-term post TAVR.

Circadian time series proteomics reveals daily dynamics in cartilage physiology.

OBJECTIVE: Cartilage in joints such as the hip and knee experiences repeated phases of heavy loading and low load recovery during the 24-h day/night cycle. Our previous work has shown 24 h rhythmic changes in gene expression at transcript level between night and day in wild type mouse cartilage which is lost in a circadian clock knock-out mouse model. However, it remains unknown to what extent circadian rhythms also regulate protein level gene expression in this matrix rich tissue. METHODS: We investigated daily changes of protein abundance in mouse femoral head articular cartilage by performing a 48-h time-series LC-MS/MS analysis. RESULTS: Out of the 1,177 proteins we identified across all time points, 145 proteins showed rhythmic changes in their abundance within the femoral head cartilage. Among these were molecules that have been implicated in key cartilage functions, including CTGF, MATN1, PAI-1 and PLOD1 & 2. Pathway analysis revealed that protein synthesis, cytoskeleton and glucose metabolism exhibited time-of-day dependent functions. Analysis of published cartilage proteomics datasets revealed that a significant portion of rhythmic proteins were dysregulated in osteoarthritis and/or ageing. CONCLUSIONS: Our circadian proteomics study reveals that articular cartilage is a much more dynamic tissue than previously thought, with chondrocytes driving circadian rhythms not only in gene transcription but also in protein abundance. Our results clearly call for the consideration of circadian timing mechanisms not only in cartilage biology, but also in the pathogenesis, treatment strategies and biomarker detection in osteoarthritis.

Inhibitory effects of lactoferrin on pulmonary inflammatory processes induced by lipopolysaccharide by modulating the TLR4-related pathway.

This study tested the ability of lactoferrin to modulate pulmonary inflammation. To construct in vitro and in vivo inflammatory lung models, cells from the human lung adenocarcinoma cell line (A549) were exposed to lipopolysaccharide (LPS, 1 µg/mL), and mice (CD-1) were intratracheally administered LPS [10 mg/kg of body weight (BW), tracheal lumen injection], respectively. The A549 cells were preincubated with lactoferrin (10 mg/mL), and the mice were intraperitoneally injected with lactoferrin (100 mg/kg of BW), followed by LPS treatment. The concentrations of proinflammatory cytokines (IL-1ß and TNF-α) in culture medium of A549 cells and in bronchoalveolar lavage fluid of the mice were determined using enzyme-linked immunosorbent assays. The toll-like receptor 4-related pathway (TLR4/MyD88/IRAK1/TRAF6/NFκB) was determined at gene and protein expression levels in A549 cells and mouse lung tissue. Results showed that LPS treatment significantly elevated the concentrations of IL-1ß and TNF-α in the A549 cell culture medium and in bronchoalveolar lavage fluid of the mice; it also elevated both the mRNA and protein expressions of TLR4 and the TLR4 downstream factors in A549 cells and mouse lung tissue. Nevertheless, lactoferrin apparently depressed the releases of IL-1ß and TNF-α from A549 cells and lung tissues stimulated by LPS, and significantly suppressed the TLR4 signaling pathway. Lactoferrin also promoted the enhancement of miR-146a expression in A549 cells and mouse lung tissue. Moreover, 100°C heating for 3 min caused total loss of the previously listed bioactivity of lactoferrin. Collectively, we proved that lactoferrin intervened in LPS-induced inflammation in the pulmonary cell model and in the mouse model, through inhibiting the TLR4-related pathway.

[Intein-Mediated Protein trans-Splicing of the Recombinant Streptavidin on Magnetosomes].

When expressing streptavidin recombinant polypeptide on magnetosomes (called bacterial magnetic nanoparticles, or BMPs), the presence of endogenous bacterial biotin might be detrimental. In the study, the streptavidin monomer fragment (S1-116) was fused with the intein N-terminal (termed precursor S1-116-IN), and S1-116-IN was expressed in E. coli (BL21). Meanwhile, the SA117-160 fragment was fused with the C-terminal intein, and then this chimeric polypeptide was expressed on magnetosomes by fusion with magnetosome membrance protein MamF. In the in vitro protein splicing system, the purified engineered magnetosomes (BMP-SA117-160-IC) and the S1-116-IN precursor were mixed. Intein-mediated trans-splicing reaction was induced to produce the functional magnetic beads BMP-SA. Our results indicate that intein-mediated protein trans-splicing may lead to efficient synthesis of the recombinant streptavidin on the magnetosomes, showing its promising potential to produce other functional magnetic nanoparticles.

[Blue light regulates the expression of brain derived neurotrophic factor in the habenula nucleus of depression-like rats induced by light deprivation].

Objective: To investigate the regulatory effect of blue light on the expression of brain derived neurotrophic factor (BDNF) in the habenula nucleus of depression-like rats induced by light deprivation. Methods: male SD rats were exposed to white light (white light control group, 20 rats) and constant darkness (depression model group, 60 rats), respectively. 18 days later rats in depression model group were randomly divided into three groups: depression model group (treated with constant darkness), blue light group (treated with blue light) and red light group (treated with red light). Rats in white light control group were kept in white light. All rats exposed to light were in a standard 12∶12 h Light/Dark condition at 20 lx for 36 days. Sucrose preference test was applied to evaluate depression-like symptoms of rats. The c-fos+cells in the habenula nucleus, intergeniculate leaflet and ventral lateral geniculate nucleus were detected. The phosphoylation of cAMP-response element binding protein (CREB) and the relative BDNF protein level in the habenula nucleus were measured. Results: Sucrose intake per kg body weight increased in rats exposed to blue light and returned to the level of control group (P>0.05). Sucrose intake per kg body weight in red light group and depression model group were lower than control group (P<0.05). More c-fos+cells were detected in the habenula nucleus, intergeniculate leaflet and ventral lateral geniculate nucleus from blue light group than those from depression model group (P<0.05). The relative BDNF protein level and the phosphoylation of CREB in the habenula nucleus from blue light group were higher than those from depression model group (P<0.05). Conclusion: Blue light could relieve depression-like symptoms in light-deprived rats. Exposure to blue light could activate neurons in the habenula nucleus to which intrinsically photosensitive retinal ganglion cells projected. Blue-light-mediated antidepressant effect might involve in the activation of CREB/BDNF signal transduction pathways in the habenula nucleus.

[Vigilance against a highly lethal insecticide chlorfenapyr poisoning (report of 4 cases and literature review)].

In order to improve the clinical attention to the poisoning of chlorfenapyr, the diagnosis and treatment strategy of chlorfenapyr poisoning were discussed. This paper collected 4 cases of chlorfenapyr in the emergency department of the Second Hospital of Hebei Medical University and 4 cases of literature review, summarized the clinical characteristics of pesticide poisoning cases containing chlorfenapyr in China, and summarized and analyzed the clinical data of the cases. Seven of the 8 patients died from poisoning by chlorfenapyr. Exposure to chlorfenapyr through respiratory tract and digestive tract showed high mortality. Fever, hyperhidrosis, elevated muscle enzymes and progressive central nerve damage were its prominent clinical characteristics. Most of the initial symptoms of exposure were not serious. Some patients, especially those with low exposure dose, had a relatively stable stage with or without clinical diagnosis and treatment. In case of sweating, obvious fever and disturbance of consciousness, the condition would deteriorate rapidly, respiratory and circulatory failure and eventually die. With the increase of production capacity and market launch, people have more opportunities to be exposed to chlorfenapyr. It is urgent to strengthen the basic and clinical research of chlorfenapyr poisoning; Attention should be paid to the observation and treatment in the initial stable stage of poisoning, which can be used as a reference for the treatment of oxidative phosphoric acid dissolving coupling agent (sodium pentachlorophenol) poisoning.

A mixture of potassium sorbate and sodium benzoate improved fermentation quality of whole-plant corn silage by shifting bacterial communities.

AIMS: To investigate the changes in fermentation quality of whole-plant corn silage ensiled with varying dosages of mixed organic acid salts (MS), and link these dosage changes to shifts in bacterial composition. METHODS AND RESULTS: Fermentation quality and bacterial community of corn silage ensiled with MS at four application rates (0, 0·67 g kg-1 , 1·33 g kg-1 , and 2·00 g kg-1 ) were investigated. The MS consisted of 40% potassium sorbate and 60% sodium benzoate. The corn silages were conserved for 42 days. Dry matter losses and ammonia nitrogen concentration were linearly declined by up to 19·10 and 33·3% with increasing dosages of MS. MS treatments significantly reduced the pH of silage vs the control group. Further analysis indicated that the improvement of fermentation quality was the result of shifts in bacterial composition, the relative abundance of Lactobacillus paralimentarius and Pediococcus spp. increased while Lactobacillus reuteri, Lactobacillus coryniformis and Klebsiella declined with increasing dosages of MS. CONCLUSIONS: MS effectively improved the fermentation quality of whole-plant corn silage with an optimum dosage of 2·00 g kg-1 . SIGNIFICANCE AND IMPACT OF THE STUDY: The correlation between bacterial taxa and fermentation quality provides a potential for the development of novel silage inoculants and for the application of MS on controlling Klebsiella mastitis of livestock farms.

Calcium propionate supplementation alters the ruminal bacterial and archaeal communities in pre- and postweaning calves.

The aim of this study was to determine the effect of calcium propionate (CaP) on rumen microbiota, fermentation indicators, and weight gain in calves both pre- and postweaning. Twenty-four newborn calves were randomly divided into 4 groups (2 × 2 factorial treatment arrangement): either pre- (90 d) or postweaning (160 d), and either without or with dietary CaP supplementation (5% dry matter). The CaP supplementation increased the body weight and rumen weight of the calves and lowered NH3-N concentration in the rumen. Microbiota composition was characterized by sequencing the amplicons of the bacterial and archaeal 16S rRNA genes. The CaP supplementation decreased the relative abundance of the phylum Bacteroidetes but tended to increase that of Proteobacteria. In addition, CaP supplementation decreased the diversity of bacteria and archaea in the rumen compared with the calves fed the control diet. Linear discriminant analysis of the rumen microbiota revealed that Succinivibrionaceae and Methanobrevibacter were enriched in the CaP group postweaning. A correlation was also present between the acetate to propionate ratio and the species that acted as co-occurrence network hubs, including Succiniclasticum, Treponema, and Megasphaera. In conclusion, CaP supplementation can improve body weight gain and rumen growth and alter the ruminal microbiota in calves both pre- and postweaning.

[Detection and evaluation of SARS-CoV-2 nucleic acid contamination in corona virus disease 19 ward surroundings and the surface of medical staff's protective equipment].

OBJECTIVE: To determine the environmental contamination degree of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in corona virus disease 2019 (COVID-19) wards, to offer gui-dance for the infection control and to improve safety practices for medical staff, by sampling and detecting SARS-CoV-2 nucleic acid from the air of hospital wards, the high-frequency contact surfaces in the contaminated area and the surfaces of medical staff's protective equipment in a COVID-19 designated hospital in Wuhan, China. METHODS: From March 11 to March 19, 2020, we collected air samples from the clean area, the buffer room and the contaminated area respectively in the COVID-19 wards using a portable bioaerosol concentrator WA-15. And sterile premoistened swabs were used to sample the high-frequency contacted surfaces in the contaminated area and the surfaces of medical staff's protective equipment including outermost gloves, tracheotomy operator's positive pressure respiratory protective hood and isolation clothing. The SARS-CoV-2 nucleic acid of the samples were detected by real-time fluorescence quantitative PCR. During the isolation medical observation period, those medical staff who worked in the COVID-19 wards were detected for SARS-CoV-2 nucleic acid with oropharyngeal swabs, IgM and IgG antibody in the sera, and chest CT scans to confirm the infection status of COVID-19. RESULTS: No SARS-CoV-2 nucleic acid was detected in the tested samples, including the 90 air samples from the COVID-19 wards including clean area, buffer room and contaminated area, the 38 high-frequency contact surfaces samples of the contaminated area and 16 surface samples of medical staff's protective equipment including outermost gloves and isolation clothing. Moreover, detection of SARS-CoV-2 nucleic acid by oropharyngeal swabs and IgM, IgG antibodies in the sera of all the health-care workers who participated in the treatment for COVID-19 were all negative. Besides, no chest CT scan images of medical staff exhibited COVID-19 lung presentations. CONCLUSION: Good ventilation conditions, strict disinfection of environmental facilities in hospital wards, guidance for correct habits in patients, and strict hand hygiene during medical staff are important to reduce the formation of viral aerosols, cut down the aerosol load, and avoid cross-infection in isolation wards. In the face of infectious diseases that were not fully mastered but ma-naged as class A, it is safe for medical personnel to be equipped at a high level.

[Study on the expression of non-coding microRNA-376b-3p in serum exosomes of patients with malignant glioma and the mechanism of anti-angiogenesis].

Objective: To screen the different microRNAs in the serum exosomes of patients with malignant glioma, to explore the effect of non-coding microRNA-376b-3p (miR-376b-3p) on the proliferation, invasion and tumor vasculogenic mimicry of glioma cells, and to verify its targeting effect on HOXD10. Methods: HiSeq/MiSeq high-throughput sequencing was used to screen the different microRNA expression profiles, target genes and action pathways in the serum exosomes of patients with malignant glioma. Samples were used to evaluate the expression of candidate microRNAs in serum exosomes of high-grade gliomas. The effects of miR-376b-3p on the proliferation, invasion and angiogenesis of glioma cells were detected by MTT assay, Transwell migration assay and Matrigel vasculogenic mimicry assay. The mRNA and protein expression of HOXD10 were detected to evaluate the regulatory effect of miR-376b-3p on it. Results: There were 144 different expression microRNAs in the serum exosomes between malignant glioma and the normal control. Focal adhesion and tumor protein polysaccharides were involved in the regulation of glioma enriched by KEGG(Kyoto Encyclopedia of Genes and Genomes). MiR-376b-3p was down regulated in malignant glioma, and AUC of malignant glioma was 0.85 (P<0.01). MTT test showed that the proliferation ability of miR-376b-3p inhibitor group was higher than that of the control group, and that of miR-376b-3p mimic group was lower than that of the control group. Transwell migration test showed that the number of transmembrane cells in miR-376b-3p inhibitor group was higher than that in NC inhibitor group, and the number of transmembrane cells in miR-376b-3p mimic group was lower than that in NC mimic group. The number of tubes of vasculogenic mimicry in miR-376b-3p mimic group was lower than that in NC mimic group. MiR-376b-3p inhibitor decreased the expression level of HOXD10 mRNA and protein, and miR-376b-3p mimic increased the expression level of HOXD10 mRNA and protein. Conclusions: MiR-376b-3p is down-regulated in the serum exosomes of malignant glioma patients. The up-regulated miR-376b-3p can reduce the proliferation and invasion of glioma cells, inhibit the formation of vasculogenic mimicry, and increase the expression of HOXD10, which is expected to inhibit the formation of two forms of angiogenesis at the same time. MiR-376b-3p may be a new therapeutic target of anti-angiogenesis for malignant glioma.

[Analysis of online education for public health and preventive medicine].

Since the outbreak of the Coronavirus Disease 2019 (COVID-19), universities have carried out online education for public health and preventive medicine courses under the policy of "Suspending Classes Without Stopping Learning" launched by the Chinese government. The Public Health and Preventive Medicine Committee of the Ministry of Education Steering Committee for Medical Education investigated the online teaching activities in the member universities. This study presents the survey results, discusses the existing problems, and proposes suggestions for further reforms on mixed teaching activities.

[Treatment of vasoproliferative tumors of the retina].

Objective: To evaluate the treatment of vasoproliferative tumors of the retina (VPTR). Methods: Retrospective case series study. The clinical data of 20 VPTR patients (20 eyes) were retrospectively analyzed, including 2 eyes only treated by cryotherapy, 1 eye only treated by photocoagulation and 1 eye only treated by ruthenium-106 brachytherapy. The remaining 16 eyes had combined treatment of ruthenium-106 brachytherapy, photodynamic therapy, anti-VEGF therapy, photocoagulation and cryotherapy. Nine eyes were also treated by vitrectomy because of complications such as retinal detachment and vitreous hemorrhage. Results: Single or multiple yellow white or orange red, highly vascular tumor lesions were found in ocular fundi of the 20 eyes. All eyes were accompanied by complications, including intraretinal and subretinal exudations (100%), macular edema (n=19, 95%), epiretinal membrane (n=4, 20%), retinal detachment (n=8, 40%), vitreous hemorrhage (n=6, 30%), abnormal blood vessels (n=16, 80%) and proliferative membrane (n=7, 35%). In the follow-up, the tumor in the eye treated by ruthenium-106 brachytherapy alone was atrophied and the vision improved. Regarding the 2 eyes treated by cryotherapy alone, macular edema and abnormal blood vessels decreased and visual acuity improved in 1 eye, and visual acuity did not change significantly in another eye. More leakages and increased visual acuity were found in the eye treated by photocoagulation alone. Among the 16 eyes treated with combined therapy, 9 eyes had decreased complications and improved visual acuity, 3 eyes did not change significantly, and 2 eyes had increased complications and decreased visual acuity. Conclusions: The conditions of VPTR are complex and difficult to treat. According to the specific conditions, clinicians should choose appropriate treatment methods; different treatment methods can be combined. Laser photocoagulation and cryotherapy may be chosen to treat small tumors complicated with abnormal blood vessels. Ruthenium-106 brachytherapy could treat big tumors complicated with exudative retinal detachment. Vitreous surgery can be used in hemorrhage and tractional retinal detachment. Anti-VEGF therapy is effective in the treatment of macular edema. (Chin J Ophthalmol, 2020, 56:272-278).

MiR-15b is a key regulator of proliferation and apoptosis of chondrocytes from patients with condylar hyperplasia by targeting IGF1, IGF1R and BCL2.

OBJECTIVE: This study aimed to explore potential microRNAs (miRNAs), which participate in the pathological process of condylar hyperplasia (CH) through targeting specific proliferation- and apoptosis- related genes of chondrocytes. METHODS: Insulin-like growth factor 1 (IGF1), IGF1 receptor (IGF1R) and B-cell CLL/lymphoma 2 (BCL2) in CH cartilage were detected by real-time polymerase chain reaction (PCR), Western blot, immunohistochemistry and immunofluorescence. MiRanda and TargetScanS algorithms were used to predict certain miRNAs in CH chondrocytes concurrently modulating the above three genes. MiR-15b was screened and identified using real-time PCR. After transfection of miR-15b mimics or inhibitor into CH chondrocytes, expression of the above three genes was detected by real-time PCR and western blot, meanwhile, cell proliferation and apoptosis was examined by CCK8, cell cycle assays, flow cytometry and Hoechst staining. Dual luciferase activity was performed to identify the direct regulation of miR-15b on IGF1, IGF1R and BCL2. RESULTS: Expression of IGF1, IGF1R and BCL2 increased in CH cartilage. Seven microRNAs concurrently correlated with IGF1, IGF1R and BCL2. Among them, only miR-15b significantly changed in CH chondrocytes. Overexpression of miR-15b in CH chondrocytes suppressed the expression of IGF1, IGF1R and BCL2, while it increased when miR-15b was knockdown. Furthermore, miR-15b suppressed their expression by directly binding to its 3'-UTR in these cells. Besides, miR-15b hampered chondrocytes proliferation through targeting IGF1 and IGF1R and accelerated chondrocytes apoptosis through targeting BCL2. CONCLUSION: Suppressed miR-15b contributed to enhanced proliferation capacity and weakened apoptosis of chondrocytes through augmentation of IGF1, IGF1R and BCL2, thereby resulting in development of CH.