Objective:To investigate the immune characteristics of SARS-CoV-2 membrane (M) protein, especially the possibility of inducing antibody-dependent enhancement effect (ADE).Methods:Full-length SARS-CoV-2 M protein was prepared by prokaryotic expression system and purified. BALB/c mice were immunized subcutaneously three times (on day 1, day 14 and day 21) by purified M protein. Serum samples were collected before immunization and after each immunization. The specificity of immune sera against M protein was identified by Western blot, and the antibody titers were detected by ELISA and neutralization test. In the presence of anti-M protein serum, the proliferation of SARS-CoV-2 in dendritic cells, nature killer cells, T and B cells was detected in vitro. Results:The immune sera from BALB/c mice immunized with purified full-length M protein of SARS-CoV-2 specifically recognized viral M protein. The titer of anti-whole virus antibody in immune sera was about 1∶400, but the antibody could not neutralize live virus. Moreover, the antibody could not help the virus to infect and proliferate in the various types of immune cells with Fc receptor (FcR).Conclusions:Non-neutralizing antibody induced by M protein could not cause ADE through FcR pathway.

BACKGROUND: We aim to explore the association between self-reported snoring and hypertension among adults aged 30-79 in Chongqing, China. METHODS: A total of 23,342 individuals aged 30-79 were included at baseline from August 2018 to January 2019, and the final sample size for the analysis was 22,423. Face-to-face interviews and physical examinations were conducted by trained investigators. Logistic regression was performed to study age-specific and gender-specific associations between snoring and hypertension. RESULTS: Frequent snoring was associated with the risk of hypertension for each age and gender group, and the frequency of snoring was positively correlated with the risk for hypertension. For the three age groups (< 45, 45-59, ≥ 60), compared with the non-snoring group, those who snore often had a 64.5%, 53.3%, and 24.5% increased risk of hypertension (< 45: OR = 1.65, 95%CI 1.34-2.02; 45-59: OR = 1.53, 95%CI 1.37-1.72; ≥ 60: OR = 1.25, 95%CI 1.09-1.42), respectively. For men and women, those who snore often had a 46.8% and 97.2% increased risk of hypertension, respectively, than the non-snoring group (men: OR = 1.47, 95%CI 1.33-1.63; women: OR = 1.97, 95%CI 1.75-2.23). CONCLUSIONS People who snore frequently should pay close attention to their blood pressure levels in order to achieve early prevention of hypertension, particularly for snorers who are female and aged under 45; importance should be attached to their blood pressure control.
Adult ; Aged ; China/epidemiology* ; Cross-Sectional Studies ; Female ; Humans ; Hypertension/etiology* ; Male ; Middle Aged ; Self Report ; Snoring/complications*

Objective: To discuss the feasibility and effectiveness of using micro-CT in bone-implant contact (BIC) evaluation in dogs, and to provide reference for clinical and scientific research. Methods: Bilateral mandibular second premolar and first molar of six male Beagle dogs were extracted. After 3 months′ healing, eight implants were placed in bilateral mandible of each dog, four on each side. Dogs were sacrificed at 2 weeks, 4 weeks and 8 weeks after implant placement, two on each time point. Samples were scanned with micro-CT and digitally reconstructed. Bone-implant interface was analyzed at different analysis regions (25, 50 and 100 μm from implants′ surface), different detection range models were obtained (each time point consists 48 models), and BIC was evaluated, and the results were counted as micro-CT₂₅, micro-CT₅₀, and micro-CT₁₀₀ groups. Then undecalcified slides were made (three slides for each sample) and stained with toluidine blue for observation and analysis of BIC using an optical microscope, and the results were counted as optical microscope groups. The advantages and disadvantages, evaluation efficiency and BIC of different methods were analyzed. Results: To evaluate BIC of single sample, it took about 90 minutes by micro-CT, which was much lower than the time of 14 days by optical microscope. The success rates of modeling of micro-CT₂₅, micro-CT₅₀, and micro-CT₁₀₀ groups all were 100.0% (48/48), and total success rate of micro-CT group was 100.0% (144/144). For optical microscope groups, the success rates of making slides 2, 4, 8 weeks were 89.6% (43/48), 93.8% (45/48) and 93.8% (45/48), respectively, and total success rates of optical microscope group was 92.4% (133/144). At 2, 4,8 weeks after implantation, BIC in micro-CT₂₅ group was significantly smaller than that in optical microscope group at the same time point (P<0.05). However, at 2, 4,8 weeks after implantation, BIC of the micro-CT₅₀ and micro-CT₁₀₀ groups showed no significant difference with optical microscope groups at the same time point (P>0.05). A significant correlation (P<0.001, each) was seen between slides and micro-CT (25, 50, 100 μm groups) concerning BIC (r=0.680, r=0.892, r=0.713), and error bias was -19.4%, -0.9%, 3.0%, respectively. The probability within the 95% limits of agreement were 97.9%. Conclusions Micro-CT is a faster, simpler and more efficient way to analyze BIC at the implant-bone interface than optical microscope observation. BIC analysis by selecting 50 μm from implants′ surface as analysis region using micro-CT is in consistent with that using the optical microscope.

Objective To evaluate the changes in the expression of hippocampal long non-coding RNAs ( lncRNAs) and bioinformatics analysis in mice with perioperative neurocognitive disorders ( PND) . Methods Thirty clean-grade male C57BL∕6 mice, aged 12-14 weeks, weighing 25-30 g, were divided into 2 groups (n=15 each) according to the random number table method: control group (group C) and PND group. The model of PND was established by performing open tibial fracture with intramedullary fixa-tion under isoflurane anesthesia in anesthetized mice. The Morris water maze test, open field test and fear conditioning test were performed at 1, 3 and 7 days postoperatively. The animals were sacrificed after the end of behavioral testing on 3 days after operation, the hippocampus was obtained, the high-throughput gene sequencing was performed to identify the differentially expressed lncRNAs, and Gene Ontology func-tional analysis and Kyoto Encyclopedia of Genes and Genomes signaling pathway analysis were used to ana-lyze the results. Results Compared with group C, the escape latency was significantly prolonged, and the percentage of time spend in the target quadrant and percentage of freezing time in the fear conditioning test were decreased at different time points after operation in group PND ( P<0. 05) . A total of 121 differential-ly expressed lncRNAs were identified, of which 69 were up-regulated and 52 were down-regulated. The Gene Ontology functional analysis showed that there were differences in various biological processes, such as synaptic transmission, cholinergic neurotransmitters, or adiponectin secretion and regulation. The KEGG signaling pathway analysis showed that there were also differences in cholinergic synapses, MAPK signaling pathway, glucagon signaling pathway, TNF signaling pathway, NOD-like receptors, Toll-like re-ceptors, chemokine signaling pathway and etc. Conclusion There are 121 differentially expressed lncR-NAs in the hippocampus of PND mice, and lncRNAs- and the target gene-related inflammatory responses, synaptic transmission, energy metabolism and etc. may be related to the pathogenesis of PND.

Objective: To establish and verify the validity of a finite element(FE) model of fragment injury in swine mandibular composite tissue. Methods: Swine facial composite tissue digital information was obtained by 3D CT,the 3D model and the cylinder fragment with the diameter and height of 5. 5 mm were reconstructed and designed in mimics15. 0. The right mandibular angle region was impacted by the fragment with velocities in finite element analysis software. A two stage light gas gun was used to launch the same shape 30CrMnSi alloy fragment with the speed of 831,1 120 and 1 536 m/s respectively to impact swine mandibular angle area. The actual damage area and acceleration at jaw were measured and compared with the digital simulation results. Results: Compared with the data of digital simulation the fragment with the speed of 831,1 120 and 1 536 m/s resulted in the larger mandibular damage area of entry in the in vivo experiment by 13. 4％,23. 6％ and 22. 3％; that of exit by 18. 7％,23. 0％ and 26. 5％; the smallar accelaration peak by 16. 7％,15. 3％ and 14. 6％,respectively. Conclusion: A digital model of the swine mandible composite tissue fragment injury model is established. The simulation results of the FE model are consistent similar to those of the in vivo test data.

Objective To understand the risk factors of hospital-acquired pneumonia(HAP) due to Carbapenem-resistant Kleb-siella pneumonia (CRKP) ,and propose prevention and control measures to reduce the incidence of hospital infection rate .Methods A total of Klebsiella pneumonia infection 73 patients with HAP ,who were treated in the ICU of a tertiary hospital in Chongqing from January 2014 to March 2016 were included .The 27 cases with CRKP were assigned as case group ,46 cases with Carbapenem-susceptible Klebsiella pneumonia(CSKP) were included as control group .Univariate and the multivariate Logistic regression analy-sis was performed for the risk factors .Results Univariate analysis showed that ,before infection ,the use of antimicrobial agents≥7 days ,Carbopenems ,mechanical ventilation ≥7 days ,APACHE Ⅱ score ,and at least 11 factors were the risk factors for CRKP HAP .Multivariate Logistic regression analysis showed that ,Carbapenems ,and mechanical ventilation≥7 days before infection and APACHE Ⅱ score was an independent risk factor of CRKP HAP .Conclusion Carbapenems ,and mechanical ventilation≥7 days before infection and APACHE Ⅱ score are the independent risk factors for CRKP HAP .Rational use of antibiotics ,reducing me-chanical ventilation and doing good hand hygiene are effective measures to reduce the incidence of CRKP HAP .

Objective:To summarize the clinical features of clear cell sarcoma of the kidney (CCSK) in children and to evaluate the effica-cy and safety of the WT-2009 chemotherapy protocol. Methods:Clinical data of children with CCSK recorded between January 2009 and December 2014 were retrospectively analyzed. Follow-ups were conducted to monitor the postoperative conditions of the pa-tients. Results:Nine cases of CCSK were recruited, and another three cases were excluded for the analysis because of incomplete clini-cal data. All patients achieved complete remission when the treatment was finished. The estimated 3-year overall survival rate was 100％, and the estimated 3-year event-free survival rate was 83.3％. No report is available on the significant side effects associated with this treatment. Conclusion:CCSK is rare in children and is easily misdiagnosed. The chemotherapy based on the WT-2009 proto-col can produce a favorable prognosis and a high tolerance for patients with CCSK. However, the treatment for high-risk patient needs to be further explored, and follow-ups must be intensified.

Objective To investigate prevalence and epidemiologic features of Saffold virus (SAFV) in hospitalized children with acute respiratory infection or digestive tract infection Tianjin area. Methods Nasopharyngeal aspirates from children with acute respiratory infection and fecal samples from children with digestive tract infection in Tianjin Children ’s Hospital were collected from January 2013 to December 2013. Viral nucleic acid was extracted, and SAFV infection was determined by using real-time quantitative PCR. Positive PCR products were sequenced. The sequencing results were aligned with known gene sequences of SAFV sequences in GenBank. The positive viral infection rate of nasopharyngeal aspirates and fecal samples, viral positive constituent ratio and positive detection rate in different age groups, seasonal distribution of SAFV infection were calculated. Other common respiratory tract or digestive tract viruses were also detected. Results Fourty-three (11.9%) nasopharyngeal aspirates from children with acute respiratory infection tested positive for SAFV. There was no significant difference between male and female infected children (aged between 6 d and 12 years old). The 79%(34/43) of the patients with SAFV infection aged under 1 year old. The infection most occurred in summer and winter. The 63 (16.4%) fecal samples from children with digestive tract infection tested positive for SAFV. There was significant difference between male and female infected children (aged between 5 h and 11 years old). SAFV infection was found to be year round. There was no significant difference in different age groups of nasopharyngeal aspirates and fecal samples. The mixed infection rate with SAFV and other respiratory tract or digestive tract viruses were 7.0%(3/43)and 12.7%(8/63), respectively. Conclusion Infection of SAFV had occurred in children with acute respiratory infection or digestive tract infection in Tianjin. SAFV has high detection rate in these children and is more common in children
aged under 1 year old. The data suggest that some of acute respiratory infection or digestive tract infections in pediatric patients are related to SAFV. The Clinical doctors should pay attention to them .

Aim To investigate whether nicorandil (Nic)protects H9c2 cardiac cells against high glucose (HG)-induced injury and inflammation by inhibiting nuclear factor-κB (NF-κB )/cyclooxygenase-2 (COX-2 )pathway.Methods Cell viability was measured by cell counter kit-8 (CCK-8)assay.The expression lev-els of NF-κB,COX-2 and cleaved caspase-3 were de-termined by Western blot.The activity of lactate dehy-drogenase (LDH)in the culture medium was measured with commercial kits.The intracellular level of reactive oxygen species (ROS)was detected by 2′,7′-dichlor-fluorescein-diacetate (DCFH-DA)staining followed by photofluorography.The number of apoptotic cells was observed by Hoechst 33258 nuclear staining followed by photofluorography.Mitochondrial membrane poten-tial (MMP)was examined by rhodamine 123 staining followed by photofluorography.The secretion levels of interleukin-1β(IL-1β) and tumor necrosis factor-α(TNF-α) were detected by ELISA.Results After H9 c2 cardiac cells were treated with 35 mmol · L-1 glucose (high glucose,HG)for 24 h,the cell viability was significantly decreased .Pre-treatment of the cells with 20~100 μmol·L-1 Nic for 60 min or 50 μmol· L-1 Nic for 30~120 min before exposure to HG signif-icantly attenuated the decrease in viability induced by HG.On the other hand,HG increased the expression levels of phosphorated (p)-NF-κB p65 and cyclooxy-genase-2 (COX-2 )in H9c2 cardiac cells.Pre-treat-ment of the cells with 50 μmol·L-1 Nic for 60 min at-tenuated the up-regulation of p-NF-κB p65 and COX-2 expression levels induced by HG.Furthermore,HG induced considerable injuries and inflammatory re-sponse,leading to increases in LDH activity,ROS generation,MMP loss,the number of apoptotic cells, the expression of cleaved caspase-3 as well as the se-cretion levels of IL-1βand TNF-α.Pre-treatment of the cells with 50 μmol·L-1 Nic for 60 min before HG exposure,or co-treatment of the cells with 100 μmol· L-1 PDTC (an inhibitor of NF-κB)or 10 μmol·L-1 NS-398 (an inhibitor of COX-2)and HG for 24 h ob-viously reduced the above injuries and inflammatory re-sponse induced by HG. Conclusion Nic protects H9 c2 cardiac cells against HG-induced injury and in-flammation by inhibiting NF-κB/COX-2 pathway.

AIM:Tostudywhe ther theangiotens in-(1-7)[Ang-(1-7)]/Mas receptor axis protects cardio-myocytes against high glucose (HG)-induced injury by inhibiting nuclear factor-κB (NF-κB) pathway.METHODS:The cell viability was measured by CCK-8 assay.The intracellular levels of reactive oxygen species ( ROS) were detected by DCFH-DA staining .The number of apoptotic cells was tested by Hoechst 33258 nuclear staining .Mitochondrial membrane potential ( MMP) was examined by JC-1 staining.The levels of NF-κB p65 subunit and cleaved caspase-3 protein were de-termined by Western blotting.RESULTS: Treatment of H9c2 cardiac cells with 35 mmol/L glucose (HG) for 30, 60, 90, 120 and 150 min significantly enhanced the levels of phosphorated ( p) NF-κB p65, peaking at 60 min.Co-treatment of the cells with 1 μmol/L Ang-(1-7) and HG for 60 min attenuated the up-regulation of p-NF-κB p65 induced by HG. Co-treatment of the cells with Ang-(1-7) at concentrations of 0.1~30μmol/L and HG for 24 h inhibited HG-induced cy-totoxicity, evidenced by an increase in cell viability .On the other hand, 1 μmol/L Ang-(1-7) ameliorated HG-induced apoptosis, oxidative stress and mitochondrial damage , indicated by decreases in the number of apoptotic cells , cleaved caspase-3 level, ROS generation and MMP loss .However, the above cardioprotective effects of Ang-(1-7) were markedly blocked by A-779, an antagonist of Ang-(1-7) receptor (Mas receptor).Similarly, co-treatment of H9c2 cardiac cells with 100 μmol/L PDTC ( an inhibitor of NF-κB) and HG for 24 h also obviously reduced the above injuries induced by HG.CONCLUSION:Ang-(1-7)/Mas receptor axis prevents the cardiomyocytes from the HG-induced injury by inhibiting NF-κB pathway .