Efficacy of bioabsorbable dressing combined with antibacterial spray for treatment of third-degree burns.

OBJECTIVE: To evaluate the clinical efficacy of a bioabsorbable dressing in combination with antibacterial spray in treating third-degree burns. METHOD: Patients with third-degree burns in our hospital from February 2019 to February 2020 were enrolled and divided into an experimental group and a control group. In all patients, two wound repair surgeries were performed. During the first surgery, bioabsorbable dressing (PELNAC, Gunze Medical Equipment (Shenzhen) Co. Ltd., China) was used for wound treatment. During the second surgery, autologous split-thickness skin graft was performed. For patients in the experimental group, bioabsorbable dressings (PELNAC) were uniformly applied with antibacterial spray during the operation and during postoperative dressing. For patients in the control group, antibacterial spray was not used. RESULTS: A total of 68 patients took part in the study (experimental group n=36; control group n=32). Infection rate in the experimental group was significantly lower than that in the control group (2.8% versus 21.9%, respectively; p<0.05). The mean wound healing time in the experimental group was shorter by 3.2 days and the wound healing rate of the experimental group was significantly higher than that in the control group (p<0.05). Vancouver Scar Scale (VSS) scores at specific postoperative time intervals were significantly reduced in the experimental group compared with those in the control group (p<0.05). CONCLUSION: Bioabsorbable dressing combined with antibacterial spray could reduce infection rate, shorten wound healing time and reduce scar formation in repairing third-degree burns.

Discovery and distribution of and response to arbovirus in China over the past seven decades / 中国血吸虫病防治杂志

Arbovirus is a group of virus transmitted by blood-sucking arthropod bites, which infects both arthropods and vertebrates. More than 600 arboviruses have been characterized worldwide until now, including 65 highly pathogenic viruses, which pose a high threat to public health. The risk of arbovirus transmission is increasing due to climate change, international trade and urbanization. The review summarizes the discovery and distribution of emerging and reemerging arboviruses and novel arboviruses with potential pathogenic risks, and proposes responses to the arbovirus transmission risk, so as to provide insights into the research and management of arboviruses and arthropod-borne infectious diseases in China.

Preclinical evaluation of RQ3013, a broad-spectrum mRNA vaccine against SARS-CoV-2 variants

The global emergence of SARS-CoV-2 variants has led to increasing breakthrough infections in vaccinated populations, calling for an urgent need to develop more effective and broad-spectrum vaccines to combat COVID-19. Here we report the preclinical development of RQ3013, an mRNA vaccine candidate intended to bring broad protection against SARS-CoV-2 variants of concern (VOCs). RQ3013, which contains pseudouridine-modified mRNAs formulated in lipid nanoparticles, encodes the spike(S) protein harboring a combination of mutations responsible for immune evasion of VOCs. Here we characterized the expressed S immunogen and evaluated the immunogenicity, efficacy, and safety of RQ3013 in various animal models. RQ3013 elicited robust immune responses in mice, hamsters, and nonhuman primates (NHP). It can induce high titers of antibodies with broad cross-neutralizing ability against the Wild-type, B.1.1.7, B.1.351, B.1.617.2, and the omicron B.1.1.529 variants. In mice and NHP, two doses of RQ3013 protected the upper and lower respiratory tract against infection by SARS-CoV-2 and its variants. We also proved the safety of RQ3013 in NHP models. Our results provided key support for the evaluation of RQ3013 in clinical trials.

Single-dose AAV-based vaccine induces a high level of neutralizing antibodies and provides long-term protection against SARS-CoV-2 in rhesus macaques

Coronavirus disease 2019 (COVID-19), which is triggered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, continues to threaten global public health. Developing a vaccine that only requires single immunization but provides long-term protection for the prevention and control of COVID-19 is important. Here, we developed an adeno-associated virus (AAV)-based vaccine expressing a stable receptor-binding domain (SRBD) protein. The vaccine requires only a single shot but provides effective neutralizing antibodies (NAbs) over 598 days in rhesus macaques (Macaca mulatta). Importantly, our results showed that the NAbs were kept in high level and long lasting against authentic wild-type SARS-CoV-2, Beta, Delta and Omicron variants using plaque reduction neutralization test. Of note, although we detected pre-existing AAV2/9 antibodies before immunization, the vaccine still induced high and effective NAbs against COVID-19 in rhesus macaques. AAV-SRBD immune serum also efficiently inhibited the binding of ACE2 with RBD in the SARS-CoV-2 B.1.1.7 (Alpha), B.1.351 (Beta), P.1/P.2 (Gamma), B.1.617.2 (Delta), B.1.617.1/3(Kappa), and C.37 (Lambda) variants. Thus, these data suggest that the vaccine has great potential to prevent the spread of SARS-CoV-2.

A human antibody with blocking activity to RBD proteins of multiple SARS-CoV-2 variants including B.1.351 showed potent prophylactic and therapeutic efficacy against SARS-CoV-2 in rhesus macaques

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which causes coronavirus disease-2019 (COVID-19), interacts with the host cell receptor angiotensin-converting enzyme 2 (hACE2) via its spike 1 protein for infection. After the virus sequence was published, we identified two potent antibodies against SARS-CoV-2 RBD from antibody libraries using a phage-to-yeast (PtY) display platform in only 10 days. Our lead antibody JMB2002, now in a phase I clinical trial, showed broad-spectrum in vitro blocking activity against hACE2 binding to the RBD of multiple SARS-CoV-2 variants including B.1.351 that was reportedly much more resistant to neutralization by convalescent plasma, vaccine sera and some clinical stage neutralizing antibodies. Furthermore, JMB2002 has demonstrated complete prophylactic and potent therapeutic efficacy in a rhesus macaque disease model. Prophylactic and therapeutic countermeasure intervention of SARS-CoV-2 using JMB2002 would likely slow down the transmission of currently emerged SARS-CoV-2 variants and result in more efficient control of the COVID-19 pandemic.

Advances of phage receptor binding proteins / 生物工程学报

Bacteriophages bind to the bacteria receptor through the receptor binding proteins (RBPs), a process that requires the involvement of complex atomic structures and conformational changes. In response to bacteriophage infection, bacteria have developed a variety of resistance mechanisms, while bacteriophages have also evolved multiple antagonistic mechanisms to escape host resistance. The exploration of the "adsorption-anti adsorption-escape process" between bacteriophages and bacteria helps us better understand the co-evolution process of bacteriophages and bacteria, which is important for the development of phage therapeutic technologies and phage-based biotechnologies. This review summarizes the bacteriophage adsorption related proteins, how bacteriophages escape host resistance based on the RBP alternations, and the recent progress of RBP-related biotechnologies.

First study on surveillance of SARS-CoV-2 RNA in wastewater systems and related environments in Wuhan: Post-lockdown

Wastewater-based epidemiology (WBE) has emerged as an effective environmental surveillance tool in monitoring fecal-oral pathogen infections within a community. Congruently, SARS-CoV-2 virus, the etiologic agent of COVID-19, has been demonstrated to infect the gastrointestinal tissues, and be shed in feces. In the present study, SARS-CoV-2 RNA was concentrated from wastewater, sludge, surface water, ground water, and soil samples of municipal and hospital wastewater systems and related environment in Wuhan during the COVID-19 middle and low risk periods, and the viral RNA copies quantified using RT-qPCR. From the findings of this study, during the middle risk period, one influent sample and three secondary treatment effluents collected from Waste Water Treatment Plant 2 (WWTP2), as well as two influent samples from wastewater system of Hospital 2 were SARS-CoV-2 RNA positive. One sludge sample collected from Hospital 4; which was obtained during low risk period, was positive for SARS-CoV-2 RNA. These study findings demonstrate the significance of WBE in continuous surveilling and monitoring of SARS-CoV-2 at the community level, even when the COVID19 prevalence is low. Therefore, the application of WBE is principally useful in tracking the level of infections in communities and the risk assessment of the secondary environment.

Current status and future challenges of high-level biosafety laboratories in China.

High-level biosafety laboratories are safe and secure platforms which integrate reliable containment, well-trained personnel, and specific biosafety manuals and practices to protect researchers from being infected while manipulating microbial pathogens and prevent pathogens from being released into the outside environment. During the past decades, laboratories with different protection levels have been constructed and operated, the legal framework and a laboratory biosafety management system have been established, and these operational laboratories have played an essential role in combatting emerging and re-emerging infectious diseases in China. Here, we have summarized the significant achievements of high-level laboratory planning, construction, and operation in China, as well as the challenges that we face in the future. Additionally, we have briefly discussed the national plan for construction of high-level biosafety laboratories from 2016-2025 and "biosafety-motivated" management system. This review might be informative for further understanding the present situation and future function of high-level biosafety laboratories in China.

Recombinant Crimean-Congo hemorrhagic fever virus with Nanoluciferase reporter and its potential application for rapid antiviral compounds screening / 中华实验和临床病毒学杂志

Objective@#To construct the recombinant Crimean-Congo hemorrhagic fever virus (CCHFV) which can express the secreted nanoluciferase (NanoLuc) and investigate its potential application for rapid antiviral compounds screening.@*Methods@#The ORF of NanoLuc and the mucin encoded by the M segment of CCHFV were merged, and the recombinant CCHFV (rCCHFV) was rescued through reverse genetic system. Then rCCHFV was used to evaluate the antiviral effect for ribavirin and Furin inhibitor in vitro.@*Results@#The rCCHFV_mucin_NLuc with NanoLuc reporter was obtained, and the relative light unit (RLU) which can reflect NanoLuc activity was positively correlated with median tissue culture infective dose (TCID50) in the infected cell supernatant (cor=0.998, P=0.001). When the concentration for the compounds was 10 μmol/L, there was no significant difference for the NanoLuc activity in the infected cell supernatant between Furin inhibitor and ribavirin (P > 0.1) from day 1 to 3 after treatment. But at day 4, the NanoLuc activity in Fruin inhibitor treated group was significantly higher than that of ribavirin treated group (P=0.001), and no significant difference was found between the Furin inhibitor and untreated group (P > 0.1).@*Conclusions@#The rCCHFV with NanoLuc reporter was recovered successfully and it could be used for the primary rapid screening of antiviral compounds in future.

Expression of lncRNA TUSC7 in melanoma A375 cell line and its effect on proliferation and apoptosis of melanoma cells / 临床与实验病理学杂志

Purpose To investigate the expression level and the role of TUSC7 in human cutaneous malignant melanoma (CMM).Methods Quantitative real time-PCR (qRT-PCR) assay was performed to detect the expression of TUSC7 in 60 cases of CMM tissues,20 cases of benign nevus,4 CMM cell lines,and one normal human epidermal melanocytes.Then overexpression of TUSC7 was performed and its role in tumor progression was explored.Results TUSC7 expression was significantly downregulated in primary CMM tissues (n =60) compared to benign nevi (n =20),which were significantly downregulated in all the four melanoma cell lines,especially in A375 cells,compared with the normal melanocytes cells (all P ＜ 0.05).In comparison with the A375 cells transfected with the empty plasmid,those transfected with pcDNA-TUSC7 showed an obvious decrease in the proliferation and colony formation activity,while increase in the apoptosis rate (all P ＜ 0.05).Conclusion Our results suggested that the dysregulation of TUSC7 may play an important role in the CMM progression.

Synchronous treatment of combined choledochoscopy, duodenoscopy and laparoscopy for management-failed biliary calculi / 中国内镜杂志

Objective To summarize the experience of applying choledochoscopy, duodenoscopy and laparoscopy, one-stage suturing of common bile duct, to treat cholecystolithiasis and choledocholithiasis that failed to respond to ordinary endoscopic sphincterotomy (EST). Methods Retrospectively analyzed the clinical data of twenty-five pa-tients with choledocholithiasis complicated with cholecystolithiasis. 25 cases of failure to endoscopic stone extraction underwent LC and laparoscopic common bile duct exploration with primary suture of (BD) from June 2013 to June 2015. Results One patient was converted to laparotomy with small incision. The other one had residual stones and therefore underwent a second EST. After the treatment, two patients developed hyperamylasemia, which was cured by conservative therapy; One patient had bile leakage, which was treated by percutaneous drainage with no serious complications and death. No long-term complication was found in a portion of patients followed up until now. Conclusion In properly selected patients of duodenoscopy management-failed, synchronous treatment of combined application of three endoscopies in laparoscopic surgery with primary suture of (BD) is feasible, effective and safe.

Transformation and standardization of the inactivation test method for virus suspension in biosafety laboratory / 中国比较医学杂志

Chemical disinfectants are generally used for virus inactivation and environment disinfection in biosafety laboratory, and the efficacy and evaluation of the disinfection are critical to ensure the laboratory biosafety.However, there is a current lack of applied standard to evaluate the virucidal efficacy of chemical disinfectants in our country.In this paper, a European Union standard“Method and Requirements of Virucidal Quantitative Suspension Test Method for Chemical Disinfectants Used in Human Medicine” was analyzed and a standard transformation scheme has been proposed.It is suggested that the model viruses should be increased from 3 to 6, including the surrogate viruses to substitute highly pathogenic viruses, and that the method to remove the residual chemical disinfectant and the calculation of 95%confidence interval should be incorporated into the standard.The suggestion will improve the scientific and operational standards related to disinfection and sterilization in biosafety laboratory in China.

Critical role of Dengue Virus NS1 protein in viral replication / 中国病毒学·英文版

Dengue virus (DENV) nonstructural protein 1 (NS1) is a highly conserved 46-kDa protein that contains 2 glycosylation sites (Asn-130 and Asn-207) and 12 conserved cysteine (Cys) residues. Here, we performed site-directed mutagenesis to generate systematic mutants of viral strain TSV01. The results of the subsequent analysis showed that an alanine substitution at the second N-linked glycan Asn-207 in NS1 delayed viral RNA synthesis, reduced virus plaque size, and weakened the cytopathic effect. Three mutants at Cys sites (Cys-4, Cys-55, Cys-291) and a C-terminal deletion (ΔC) mutant signiifcantly impaired RNA synthesis, and consequently abolished viral growth, whereas alanine mutations at Asn-130 and Glu-173 resulted in phenotypes that were similar to the wild-type (WT) virus. Further analysis showed that the Asn-207 mutation slightly delayed viral replication. These results suggest that the three conserved disulifde bonds and the second N-linked glycan in NS1 are required for DENV-2 replication.

Survey on dietary intake of phytosterols in middle-aged and elderly populations in Guangzhou / 中华临床营养杂志

ObjectiveTo investigate the dietary intake of phytosterols in middle-aged and elderly residents in Guangzhou.Methods The dietary data were collected from 599 middle-aged and elderly residents (222 men and 377 women) recruited by stratified cluster random sampling in Guangzhou.All the subjects were surveyed using Food Frequency Questionnaire (FFQ).The dietary intake of phytosterols was estimated using Chinese data of phytosterol composition of a range of foods.ResultsThe dietary intake of total phytosterols was 336.36 ±142.88 mg/d,which included β-sitosterol 218.53 ± 95.20 mg/d,campesterol 48.33 ± 23.69 mg/d,stigmasterol 36.40 ± 14.38 mg/d,β-sitostanol 30.65 ± 13.62 mg/d,and campestanol 4.67 ±2.77 mg/d.Women had a significantly higher intake of phytosterols than men [ (345.45 ±141.06) mg/d vs.(320.93 ±144.95) mg/d,P=0.0425].Edible oil,vegetable,cereal,and fruit were the four major food sources of phytosterols,representing 37.2％,19.8％,18.5％,and 12.5％ of the total phytosterols intake respectively.Energy-adjusted intake of phytosterols was (42.94 ± 15.66) mg/1000 kJ,and women had a significantly higher intake than men [ (46.04 ±15.90) mg/1000 kJ vs.(37.69 ± 13.76) mg/1000 kJ,P =0.0000 ].ConclusionAmong the middle-aged and elderly residents in Guangzhou,women have higher phytosterols intake than men.

Rapid Detection of Filoviruses by Real-time TaqMan Polymerase Chain Reaction Assays / 中国病毒学·英文版

Ebola virus (EBOV) and Marburg virus (MARV) are causative agents of severe hemorrhagic fever with high mortality rates in humans and non-human primates and there is currently no licensed vaccine or therapeutics.To date,there is no specific laboratory diagnostic test in China,while there is a national need to provide differential diagnosis during outbreaks and for instituting acceptable quarantine procedures.In this study,the TaqMan RT-PCR assays targeting the nucleoprotein genes of the Zaire Ebolavirus (ZEBOV) and MARV were developed and their sensitivities and specificities were investigated.Our results indicated that the assays were able to make reliable diagnosis over a wide range of virus copies from 103 to 109,corresponding to the threshold of a standard RNA transcript.The results showed that there were about 1010 RNA copies per milliliter of virus culture supernatant,equivalent to 10,000 RNA molecules per infectious virion,suggesting the presence of many non-infectious particles.These data indicated that the TaqMan RT-PCR assays developed in this study will be suitable for future surveillance and specific diagnosis of ZEBOV and MARV in China.

Surface Display of Domain Ⅲ of Japanese Encephalitis Virus E Protein on Salmonella Typhimurium by Using an Ice Nucleation Protein / 中国病毒学·英文版

A bacterial cell surface display technique based on an ice nucleation protein has been employed for the development of live vaccine against viral infection.Due to its ubiquitous ability to invade host cells,Salmonella typhimurium might be a good candidate for displaying viral antigens.We demonstrated the surface display of domain III of Japanese encephalitis virus E protein and the enhanced green fluorescent protein on S.typhimurium BRD509 using the ice nucleation protein.The effects of the motif in the ice nucleation protein on the effective display of integral protein were also investigated.The results showed that display motifs in the protein can target integral foreign protein on the surface of S.typhimurium BRD509.Moreover,recombinant strains with surface displayed viral proteins retained their invasiveness,suggesting that the recombinant S.typhimurium can be used as live vaccine vector for eliciting complete immunogenicity.The data may yield better understanding of the mechanism by which ice nucleation protein displays foreign proteins in the Salmonella strain.

A Virus-type Specific Serological Diagnosis of Flavivirus Infection Using Virus-like Particles / 中国病毒学·英文版

Many flaviviruses are emerging and reemerging pathogens, such as West Nile virus (WNV), dengue virus (DENV), yellow fever virus (YFV), and Japanese encephalitis virus. Serological assay is the dominant method for diagnosis of flavivirus infections in human. Because antibodies generated during flavivirus infections cross-react with other flavivirus members, plaque reduction neutralization test (PRNT) is the only available assay to determine the infecting flavivirus type.Since PRNT requires culturing raw viruses, it must be performed in biosafety level-3 or level-4 containment for many flaviviruses, and takes more than ten days to complete. To overcome these problems, we have developed flavivirus viral-like particles (VLPs) that could be used to replace raw viruses in the neutralization assay. The VLPs were prepared by trans packaging a luciferase-reporting replicon with viral structural proteins. This novel assay involves three simple steps: (ⅰ) VLPs from a panel of flaviviruses are incubated with flavivirus-infected sera at 37℃ for 1 h; (ⅱ)the neutralized VLPs are used to infect Vero cells; and (ⅲ) the infected cells are measured for luciferase activities at 22 h post-infection. The virus type whose VLP is most efficiently neutralized by the serum specimen (as quantified by the luciferase activities) is the etiologic agent. As a proof-of-concept, we show that a WNV-infected mouse serum neutralized the WNV VLP more efficiently and selectively than the DENV and YFV VLPs. Our results demonstrate that the VLP neutralization assay maintains the "gold standard" of the classic PRNT; importantly, it shortens the assay time from ＞10 days to ＜1 day, and can be performed in biosafety level-2 facility.

Preliminary characterization of a thermostable DNA polymerase I from a mesophilic Bacillus sphaericus strain C3-41.

A thermostable DNA polymerase I from a mesophilic Bacillus sphaericus strain C3-41 was characterized in this study. The polI was cloned, sequenced and over-expressed in Escherichia coli. The expressed 110 kDa fusion protein of PolI was stable at 70 degrees C for 1 h. Compared with DNA polymerase I of E. coli (TaKaRa), the relative polymerase activity of this PolI was 3.33 +/- 0.1 RFU microl(-1) at 37 degrees C using fluorescent quantitative analysis. It showed higher polymerase activity than E. coli PolI at higher temperature, with a relative activity of 3.75 +/- 0.1 RFU microl(-1) at 70 degrees C. The polI sequence analysis and the protein structure prediction indicated that this protein had a high similarly to other PolI from thermophilic micro-organisms. This information is of importance for future study for evolution of the house-keeping gene polI in entomopathogenic bacterium B. sphaericus.

Effect of comprehensive rehabilitation therapy on ADL of old patients with stroke / 中国康复理论与实践

@# ObjectiveTo study the effect of comprehensive rehabilitation therapy on activity of daily living(ADL) of old patients with stroke.Methods56 old patients with stroke were rehabilitated by the therapy of Bobath,Brunnstrom,Rood,PNF and psychotherapy for 3 months.The Modified Barthel Index (MBI) was applied to measure ADL before and after treatment.ResultsAfter treatment,the MBI of the patients was markedly higher than before(P<0.01),which was relative with the recovery of movement function and the psychology.ConclusionsThe rehabilitation therapy can improve ADL of old patients on stroke.