The aim of this study was to qualitatively and quantitatively detect coronavirus(CoV)in the feces of bats from Qinghua Cave,Yunnan Province,China.CoV was qualitatively tested with reverse transcription polymerase chain reaction(RT-PCR),and homology and genetic evolution were analyzed with bioinformatics software.The established reverse transcription real-time fluores-cence quantitative PCR(qRT-PCR)method was applied to CoV quantification in bat feces.The positivity rate of CoV in 306 fecal samples collected from the fulvous fruit bat(Rousettus leschenaultia)was 7.8%(24/306)according to RT-PCR.All 24 strains of CoV belonged to β-CoV,and showed a similarity of 86.8%-100.0%at the nucleotide level and 95.2%-100.0%at the amino acid level,with respect to other β-CoV sequences in the NCBI database.The positivity rate of CoV was 18.6%(57/306)according to qRT-PCR,a value higher than that according to RT-PCR(χ2=25.3,P<0.05).The mean β-CoV load was 1.3×103 copies/μL.In conclusion,the bats in Qinghua Cave,Yunnan Province,carried CoV belonging to β-CoV.The established qRT-PCR method achieved good sensitiv-ity,accuracy,reproducibility,and a higher detection rate than that of RT-PCR,and can be used for rapid detection of β-CoV in bats.

The aim of this study was to qualitatively and quantitatively detect coronavirus(CoV)in the feces of bats from Qinghua Cave,Yunnan Province,China.CoV was qualitatively tested with reverse transcription polymerase chain reaction(RT-PCR),and homology and genetic evolution were analyzed with bioinformatics software.The established reverse transcription real-time fluores-cence quantitative PCR(qRT-PCR)method was applied to CoV quantification in bat feces.The positivity rate of CoV in 306 fecal samples collected from the fulvous fruit bat(Rousettus leschenaultia)was 7.8%(24/306)according to RT-PCR.All 24 strains of CoV belonged to β-CoV,and showed a similarity of 86.8%-100.0%at the nucleotide level and 95.2%-100.0%at the amino acid level,with respect to other β-CoV sequences in the NCBI database.The positivity rate of CoV was 18.6%(57/306)according to qRT-PCR,a value higher than that according to RT-PCR(χ2=25.3,P<0.05).The mean β-CoV load was 1.3×103 copies/μL.In conclusion,the bats in Qinghua Cave,Yunnan Province,carried CoV belonging to β-CoV.The established qRT-PCR method achieved good sensitiv-ity,accuracy,reproducibility,and a higher detection rate than that of RT-PCR,and can be used for rapid detection of β-CoV in bats.

Objective:In this study, the collected mosquito samples were subjected to viral isolation to identify the species and branch characteristics of arboviruses in five regions of Shanxi Province.Methods:Eight arboviruses in mosquito samples collected from July to September 2020 were detected by real-time fluorescent quantitative PCR, and virus isolation was carried out through cell culture. Virus isolates were identified and analyzed by molecular biology and bioinformatics method.Results:We detected 1 batch of positive samples of Japanese encephalitis virus, 2 batches of positive samples of Culex flavivirus and 8 batches of positive samples of Nam Dinh virus among 121 batches of mosquito samples. Seven virus isolates were isolated, numbered: SX-YJ-Cxp-4、SX-YJ-Ars-2、SX-YJ-Cxp-1、SX-LY-Cxp-10、SX-GP-Ars-5、SX-GP-Cxp-2、SX-GP-Cxp-4, all of which were identified as Nam Dinh virus, and the whole genome sequencing was performed on one of them, and the result showed that Shanxi Nam Dinh virus isolate and Yunnan Nam Dinh virus isolate belonged to the same evolutionary branch.Conclusions:Nam Dinh virus was isolated and identified on the specimen from Shanxi province for the first time.

Objective:To explore the effectiveness of college English curriculum reform for undergraduates in Chongqing Medical University from the perspective of English for specific purposes (ESP).Methods:A questionnaire survey was conducted among the nursing undergraduates in Batch 2018 for investigation of their needs on English curriculum setting, then corresponding reform measures were made and carried out among the nursing undergraduates in Batch 2019 for 1 school-term, and then their satisfaction degree to the college English curriculum reform was investigated. SPSS statistical software was used to count the number and proportion of each option for the collected data.Results:The results showed that 56.78% (272/479) of the respondents in Batch 2019 were satisfied with the college English curriculum reform and 88.1% (422/479) were satisfied with the reform of nursing English curriculum.Conclusion:The curriculum reform should take both learners' individual needs and their occupational target needs into full consideration. It is necessary to create more opportunities for learners to practice English speaking and reading. In addition, the ESP teachers can enhance their competence and confidence in ESP teaching by preparing lessons together. Needs analysis-based English curriculum reform is conducive to the improvement of English teaching effectiveness.

The formation of most proteins consists of two steps: the synthesis of precursor proteins and the synthesis of functional proteins. In these processes, propeptides play important roles in assisting protein folding or inhibiting its activity. As an important polypeptide chain coded by a gene sequence in lipase gene, propeptide usually functions as an intramolecular chaperone, assisting enzyme molecule folding. Meanwhile, some specific sites on propeptide such as glycosylated sites, have important effect on the activity, stability in extreme environment, methanol resistance and the substrate specificity of the lipase. Studying the mechanism of propeptide-mediated protein folding, as well as the influence of propeptide on lipases, will allow to regulate lipase by alternating the propeptide folding behavior and in turn pave new ways for protein engineering research.
Lipase/metabolism* ; Molecular Chaperones/metabolism* ; Protein Folding ; Protein Precursors ; Substrate Specificity

Objective:The matria-assisted laser desorption/ionization time of flight mass spectrometry(MALDI-TOF MS) and sequencing methods were performed to assess the methodology (biochemistry methods) for identifying the Pandoraea sputorum and provide the more preferred approach to identify Pandoraea species. Methods:This paper is a study on performance evaluation of identification method. Ten lines of Pandoraea sputorum were isolated from blood cultures of inpatients were collected at Zhongnan Hospital of Wuhan University from July to October 2018 and were confirmed by the cultural characteristics, colonial morphology and Gram′s stain. Further identification was carried out by using the manual biochemical method (API 20NE), automatic biochemistry systems(BioMerieuxVITEK 2 Compact, BD Phoenix-100andThemo ARIS 2X), MALDI-TOF MS (BioMerieuxVITEK MS and Bruker MALDI Biotyper) and the sequencing methods of the 16S rRNA to identify the Pandoraea sputorum. Results:Pandoraea sputorum was non-fermented gram-negative bacteria that are non-motile, oxidase positive, and catalase positive. Ten lines of Pandoraea sputorum were identified as Achromobacter denitrificans, Alcaligenes faecalis or Cupriavidus pauculus and the accuracy rate of genus and species identification was 0 by API 20NE. Among all the samples, six lines were identified as the Pandoraea spp. with the accuracy rate of genus identification was 6/10 by VITEK 2 Compact; whereas the other four lines were identified as the Burkholderia cepacia, Sphingomonas paucimobilis, Ralstonia pickettii, or "Low Discrim" . All of these were identified as "No Identification" by Phoenix-100, which the accuracy rate of genus and species identification was 0. Seven isolates were identified by ARIS 2X as Stenotrophomonas maltophilia, Acinetobacter lwoffii, Sphingomonas paucimobilis, Pseudomonas luteola, Acinetobacter baumannii/Acinetobacter haemolyticus; whereas the other three lines were identified as rare species, thus, the accuracy rate of genus and species identification was 0. Both VITEK MS and MALDI Biotyper indicated all the isolates were Pandoraea sputorum with the accuracy rate of genus and species identification was 10/10. 16S rRNA sequencing for the 10 isolates showed they have 100% of similarity to Pandoraea sputorum by blasting with Genebank. Conclusions:Methods based on biochemical reactions often failed to accurately identify the Pandoraea sputorum to species level. MALDL-TOF MS and 16S rRNA sequencing technology identify Pandoraea sputorum efficiently and precisely enough.

On October 3rd, 2017, one male patient, aged 27 years, was admitted to our hospital 6 hours after hydrothermal scald of torso, buttocks, and limbs. The total area of burn was about 60% total body surface area, and the depth was from deep partial-thickness burn to full-thickness burn. Immediately after admission, the patient was given symptomatic support treatments, such as anti-shock, fluid replacement, and anti-infection, etc. After being treated by debridement and xenogenic (porcine) skin grafting for 2 times, the wounds were healed well. On the 12th day of admission, linezolid was used to prevent infection according to the results of microbial culture and drug sensitivity test, since when the level of his blood lactate continued to increase. After 8 days, linezolid was discontinued and vitamin B1 was given orally for 1 week, and the level of lactic acid gradually decreased to normal in result. This case was used mainly to analyze whether linezolid could directly cause hyperlacticemia and its important mechanism, aiming at reminding clinicians of being alert to the risk of hyperlacticemia when using linezolid. If hyperlacticemia occurs, linezolid should be discontinued immediately and vitamin B1 should be taken orally to correct the high lactic acid value, and the treatment plan should be adjusted if necessary.

By removing a part of the structure, the tooth preparation provides restorative space, bonding surface, and finish line for various restorations on abutment. Preparation technique plays critical role in achieving the optimal result of tooth preparation. With successful application of microscope in endodontics for >30 years, there is a full expectation of microscopic dentistry. However, as relatively little progress has been made in the application of microscopic dentistry in prosthodontics, the following assumptions have been proposed: Is it suitable to choose the tooth preparation technique under the naked eye in the microscopic vision? Is there a more accurate preparation technology intended for the microscope? To obtain long-term stable therapeutic effects, is it much easier to achieve maximum tooth preservation and retinal protection and maintain periodontal tissue and oral function health under microscopic vision? Whether the microscopic prosthodontics is a gimmick or a breakthrough in obtaining an ideal tooth preparation should be resolved in microscopic tooth preparation. This article attempts to illustrate the concept, core elements, and indications of microscopic minimally invasive tooth preparation, physiological basis of dental pulp, periodontium and functions involved in tool preparation, position ergonomics and visual basis for dentists, comparison of tooth preparation by naked eyes and a microscope, and comparison of different designs of microscopic minimally invasive tooth preparation techniques. Furthermore, a clinical protocol for microscopic minimally invasive tooth preparation based on target restorative space guide plate has been put forward and new insights on the quantity and shape of microscopic minimally invasive tooth preparation has been provided.

Objective Molecular biological methods were used to classify and analyze the isolated Brucella strains,and to understand the geographical distribution characteristics,genetic types and regional distribution characteristics of Brucella in Qinghai Province.Methods Molecular biology typing of species of isolated Brucella strains in Qinghai was studied using Multiple Locus Variable-number tandem repeat Analysis (MLVA) technology.The classification results were described by geographical information system (GIS).Results There were 3 species Brucella melitensis,Brucella abortus,and Brucella suis among the 65 strains of Brucella in Qinghai.Brucella melitensis was the dominant species.The genotypes of MLVA were 42,43,47,28,36,112 and 6.The geographical distribution features showed that the 42 belonged to the evolutionary branches of A and B,which was widely distributed.The 43 of the C evolutionary branch and 47 of the E evolution branch were mainly in the hinterland of the Qinghai-Tibet Plateau.When searching in the Brucella2012 MLVA database,none of the genotypes obtained in this study were identical to those in the database.Conclusions The MLVA genotypes of Brucella are varied in Qinghai Tibet Plateau.They are widely distributed,completely different from those in other areas,and different genetic variations are found in different places.

Objective:To study the metabolites of 17β-estradiol via human cytochrome enzyme CYP 1B1 and analyze the genera-tion rate of products by a high performance liquid chromatography coupled with electrochemical detector (HPLC-ECD) method.Meth-ods:A Mightysil RP-18GP (250 mm ×3.0 mm, 5 μm) column was used at the temperature of 40 ℃.The electrochemical detector with E=+900 mV was applied, the mobile phase was 0.5％NaH2PO4(pH 3.0) and methanol (45:55), the flow rate was 0.5 ml · min-1 , and the injection volume was 5μl.Results:The main metabolite was 4-OH-E2 accompanied with a little of 2-OH-E2.The average hydroxylation rate of 4-OH-E2 was about five times as much as that of 2-OH-E2 at the same concentration of estrogen E 2 me-tabolized via CYP1B1.Conclusion:Taken together, CYP1B1 catalyzed hydroxylation sites of 17-beta estradiol based on NADPH me-tabolism are maily 4.