Objective:To prepare seven standard strains of 2019 novel coronavirus (2019-nCoV), including wild type (WT) strain, Beta variant, Delta variant, Omicron variants (BA.2, BA.5, BQ.1, XBB.1 branches), which could be used to apply for national standard strains.Methods:According to cytopathic effect (CPE), virus titer, whole-virus-genome-sequencing and detection of mycoplasma, the basic biological characteristics of clonal isolation were determined through plaque purification technology.Results:The CPE was mainly characterized by cell shrinkage and exfoliation in Vero cells after infection with seven 2019-nCoV clonal isolations (WT, Beta, Delta, Omicron, BA.2, BA.5, BQ.1 and XBB.1 branches). The result of mycoplasma detection were negative and titers of the clonal isolation from 2nd to 5th generations were stable at 10 5-10 8 TCID 50/ml; the electron microscope showed that the virions were all round or elliptical, with a diameter between 60 nm and 140 nm. The subtypes of 7 strains were identified by whole-virus-genome-sequencing and phylogenetic analysis, with genomic stability after the fifth successive generations of clonal isolation. Conclusions:The series clonal isolation of 2019-nCoV with typical CPE of coronavirus, clear morphological structure, good viral activity and stable genetic characteristics were prepared, and they could be used to apply for national standard strains.

Objective:To investigate the unqualified hepatitis C virus (HCV) detection result of blood donors from the served area of blood institutions.Methods:The data related to HCV markers detected of the first and repeat blood donors were collected from the system of practice comparison for the Chinese mainland blood institutions from 2017 to 2021. The anti-HCV reactive rate and the rates of anti-HCV negative but HCV-RNA reaction and all the relationship between rates and the annual, regional and different blood donors were statistically analyzed.Results:During 2017-2021, the number of anti-HCV reactive per 100 000 blood donors decreased from 444.3 to 250.44 in the served area of 22 blood institutions ( χ2=49.677, P<0.05). The number of HCV RNA detected positive per 100 000 anti-HCV negative increased from 0.69 to 2.05 year by year, but there was no statistical significance ( χ2=0.643, P>0.05). The anti-HCV unqualified rate was significantly different among regions ( χ2=3 260.283, P<0.05). The anti-HCV unqualified rate of the first blood donors was significantly higher than that of the repeated blood donors ( F=130.993, P < 0.05). The annual number of HCV RNA detected positive per 100 000 anti-HCV negative blood samples from donors ranged from 0 to 17.28. Conclusions:The anti-HCV unqualified rate of blood donors in the served area of 22 blood institutions decreased year by year. Compared with repeated blood donors, HCV infection should be emphasized in first-time blood donors. The implementation of HCV RNA test can detect out much more HCV infections and reduce the risk of transfusion transmitted infectious HCV.

Objective To explore the diagnostic value of morphology in patients with blastic plasmacytoid dendritic cell leukemiafrom bone marrow cell.Methods Clinical data of 5 patients with BPDCN leukemia in Peking Union Medical College Hospital from 2011 to 2016were collected.The morphological characteristics of the cell size,nuclei,chromatin and cytoplasm of the BPDCNtumor cells in the bone marrow smears were observed under the microscope.Results The clinical manifestation of the 5 cases involved skin lesions (5/5,100％),lymphadenopathy (4/5,80％),hepatomegaly (3/5,60％),splenomegaly (4/5,80％).Immunophenotype showed all cases were positive for CD4,CD56 and CD123.The morphologiesof BPDCN cell characterized by heterogenous clls,were frequent,including,frequent mediumsized cells with a round or irregular nucleus,lacy chromatin,basophilic cytoplasm with lack of granules,marked large pseudopodia and vacuolation which may arranged as pearl necklace along the cytoplasmic outline.They might mimicking pseudomonoblast,Pseudolymphoblast or Pseudolymphoma cell.Conclusions Plasmacytoid dendritic cells had some peculiar morphological features,the patients suffered from the clinical manifestation of skin lesion may highly suggested the diagnosis of BPDCN,Flow cytometry and pathological biopsy are necessary for the final diagnosis of BPDCN.

Objective To establish a method for the isolation of Zika virus and to gather experi-ences for viral isolation. Methods Suckling mice at age 1-3 days were inoculated with serum samples posi-tive for Zika virus through intracranial injection. All mice were sacrificed 6 days after the injection. Viral nu-cleic acids were extracted from brain, heart, liver, spleen, lung, kidney, muscle, skin and intestine tissue samples and analyzed by real-time RT-PCR. The supernatants of brain tissues positive for Zika virus were used for subculturing. Nested PCR was performed to amplify the NS5 gene of the isolated virus. The se-quences of NS5 gene were analyzed by using MEGA6. 0 software. Results All of the tissue samples were positive for Zika virus. Higher viral loads were detected in heart and brain tissue samples with cycle thresh-old (Ct) values of 24. 4 and 25. 3, respectively. The second generation of Zika virus was identified in suck-ling mice brain tissues 2 days after infection by using real-time RT-PCR. The amplified product of nested PCR was 972 bp in length. Sequencing analysis showed that the isolated Zika virus ( GDZ16002 strain) be-longed to the Asian lineage. Conclusion A strain of Zika virus was successfully isolated in China by using intracranial injection via a suckling mouse model. The isolated Zika virus belonged to the Asian lineage.

Objective To explore the preparation and quality control of As2 O3 nanoparticle .Methods PEG‐PLA was used as the vector material to prepare As2 O3 nanoparticle with ultrasonic emulsification method ,and the VEGFR‐2 was coupled to obtain VEGFR‐2/As2 O3‐PEG‐PLA nanoparticle .The particle size distribution ,Zata potential ,loading efficiency (LE) ,encapsulation effi‐ciency(EE) ,drug release in vitro and stability was determined ,and morphological characteristics was observed by transmission elec‐tron microscope(TEM) .Tweety‐four hepatocellular carcinoma nude mices were randomly divided into VEGFR‐2/As2O3‐PEG‐PLA nanoparticles group and As2 O3‐PEG‐PLA nanoparticles group ,by tail vein injection of nanoparticles .High performance liquid chro‐matography was used to determine content of As2 O3 .After 21 d ,six nude mices in each group were killed ,and the immunohisto‐chemistry and western blot method was used to detect the expression of VEGFR‐2 .Results The particle size of VEGFR‐2/As2 O3‐PEG‐PLA was determined to be (141 .9 ± 13 .2)nm ,Zata potential was (10 .2 ± 1 .1)mV .It was found to spherical or oval shape , with uniform size and dispersibility under TEM .LE and EE was (5 .51 ± 1 .83)% and (62 .12 ± 5 .98)% ,respectively .Drug release in vitro showed that VEGFR‐2/As2 O3‐PEG‐PLA exhibited controlled release effect ,with half of the release time as 10 h .Besides , VEGFR‐2/As2 O3‐PEG‐PLA showed a good stability in 3 days .Compared with As2 O3‐PEG‐PLA nanoparticles group ,the concen‐tration of As2 O3 in tumor and liver tissue was high ,the concentration of As2 O3 in blood ,heart ,kidney tissue was low ,the expression of VEGFR‐2 in tumor tissue was low in VEGFR‐2/As2O3‐PEG‐PLA nanoparticles group(P< 0 .05) .Conclusion The prepared As2 O3 nanoparticle using PEG‐PLA as vector and VEGFR‐2 as target showed uniform size ,high EE and LE ,good stability .And it preliminarily proved that VEGFR‐2 could be targeted in nude mice .

Objective To establish an inactivated viral particle-based ELISA for the detection of antibodies against Middle East respiratory syndrome coronavirus (MERS-CoV) in serum samples collected from a MERS-CoV associated case. Methods Serum samples were collected from 10 newborns and 40 healthy adults. A viral particle-based ELISA was established by using the inactivated MERS-CoV virions as antigen. The levels of IgM and IgG antibodies in the serum samples were detected by the established ELISA and the cut-off values for positive detection were determined. Then the inactivated MERS-CoV virion-based ELISA was used to detect the antibodies against MERS-CoV in 5 serum samples collected from the first im-ported MERS case in China. Results The cut-off values of IgM and IgG antibodies in serum samples for ELISA were determined to be A450 readings of 0. 32 and 0. 42, respectively. The titers of IgM and IgG anti-bodies in serum samples collected at early admission to hospital from the first imported MERS case in China were both 1 ︰ 40. Seroconversion occurred 2 weeks after his admission to hospital with the titers of IgM and IgG reaching to 1 ︰ 320. Conclusion The inactivated MERS-CoV virion-based ELISA was established successfully and could be used for the detection of serum antibodies (IgG and IgM) in MERS associated cases.

To investigate the genetic character and origin of the first imported infection case of middle East respiratory syndrome coronavirus (named as MERS-CoV_China GD01), RNA was extracted from swabs of this patient followed by RT-PCR amplification. All coding gene of structural (S, E, M, E) and accessory (ORF3, ORF4a, ORF4b, ORF5, ORF8b) proteins were sequenced and analyzed. Phylogenetic analyses of structural protein coding genes of MERS-CoV_ China GD01 indicates that several substitutes exists in S coding gene and its origin belong group 5 of MERS-CoV, which were recent circulated in Saudi Arabia area, while other three structural genes (N, E, M) were very conserved. Phylogenetic analyses of accessory protein coding genes of MERS-CoV China GD01 indicates that several substitutes exists among ORF3, ORF4a, ORF4b and ORF5, while ORF8b was conserved. In conclusion, genome of MERS-CoV_ China GD01 was general conserved although several genetic variations were found among structural and accessory protein coding genes. This is the first report on sequencing and phylogenetic analyses of the first imported MERS case in China, which may pay the way for prevention and control of imported MERS-CoV infection.
China ; Conserved Sequence ; Coronavirus Infections ; transmission ; virology ; Evolution, Molecular ; Genomics ; Humans ; Middle East Respiratory Syndrome Coronavirus ; genetics ; physiology ; Phylogeny ; Sequence Analysis ; Viral Proteins ; genetics

The nitrate-N content in KNO3 solution and soil was rapidly predicted using techniques of mid-infrared spectroscopy, in which 15 NO-3 and 14 NO-3 were distinguished and predicted. The results showed that the characteristic band of nitrate in solution and soil was 1200-1500 cm-1 , and compared with 14 NO-3 , the red shift of characteristic band of 15 NO-3 was about 35 cm-1 . In the characteristic band of nitrate, absorption band increased with the nitrate nitrogen concentration with less interference absorption. The linear regression was made between the first principal component of characteristic band and nitrate-N content, and correlation coefficient was more than 0 . 9840 , indicating that the technique of mid-infrared attenuated total reflectance spectroscopy could be applied for rapid monitoring of nitrate in solution and soil. Meanwhile, based on the red shift characteristic of 15 NO-3 absorption band, the method of partial least squares were involved to predict the nitrate-N of different N-isotope labeled in solution and soil, resulting that all the prediction models reached excellent levels. For 14 NO3-N and 15 NO3-N in solution, the correlation coefficients ( R2 ) were 0. 9980 and 0. 9982 respectively, and ration performance to standard deviations ( RPD ) were 6. 44 and 4. 76, respectively. While for 14 NO3-N and 15 NO3-N in soil, the correlation coefficients ( R2 ) were 0. 9794 and 0. 9679, and RPD were 5. 75 and 4. 78, respectively. Therefore, the technique of mid-infrared attenuated total reflectance spectroscopy can be applied for rapid monitoring different N-isotope labeled nitrate in solution and soil, to provide a new in situ and fast time method to study nitrification process in soil.

Soil particles are very heterogeneous in microscopic scale, which is manifested the double-layer structure made of the soil organic matter and mineral matter. In this work, Fourier by transform infrared photoacoustic spectroscopy ( FTIR-PAS) combined with independent component analysis ( ICA) was utilized for in situ depth-profiling of the manmade complex film, in order to lay a foundation of in situ characterizing the heterogeneous soil organic-mineral complex. The complex film was composed of the PE preservative film and office adhesive tape. The moving velocity of infrared photoacoustic spectrometer was set to 0. 16 cm/s, 0. 32 cm/s and 0. 64 cm/s, respectively. Independent component analysis ( ICA ) was performed on the photoacoustic spectra of the heterogeneous complex film. Results showed that the depth-resolved information of the complex film could be derived by changing the moving velocity, and the estimated thickness of PE film was 5. 4-7. 6 μm, which was close to the actual thickness 7 ± 1 μm. Moverover, the spectral features of the polyethylene ( PE) preservative film and office adhesive tape were extracted from the photoacoustic spectra of the heterogeneous complex film by means of ICA. Depth profiling of complex film samples showed that FTIR-PAS could be used as a new analytical tool to study heterogeneous soils, especially soil organic-mineral complexes.

Objective To assess the clustering of cardiovascular risk factors and their effects on target organ damage in elderly patients with hypertension .Methods 421 treated elderly hypertension patients were divided into 5 groups based on the number of risk factors :hypertension without additional risk factor (group A ,25 cases) ,and the other 4 groups were complicated with 1 (group B ,76 cases) ,2(group C ,127 cases) ,3(group D ,128 cases)and ≥ 4 (group E ,65 cases) risk factors .The structure and function of heart and carotid artery were examined by ultrasonography in order to evaluate the damage of target organ and the morbidity .Re-sults The patient groups with three or more risk factors showed significantly higher levels of BMI ,plasma glucose ,triglyceride , LDL-C cholesterol ,serum creatinine and serum uric acid ,and needed greater number of antihypertensive drugs ,compared with other groups(P<0 .05) .The patient groups with two or more risk factors showed significantly higher levels of LVMI ,IMT and MAU/Cr compared with group A(P<0 .05) ,and significantly lower levels of the creatinine clearance (P<0 .05) .In addition ,they showed significantly higher incidences of coronary heart disease and cerebrovascular disease and chronic kidney disease compared with group A (P<0 .05) .Conclusion These results suggest that the hypertensive patients with clustering risk factors required greater number of antihypertensive drugs .The more additional risk factors exit ,the more target organ damages and higher morbidity occur ,and more intensive intervension are required to control not only blood pressure but also other complicated risk factors .