OBJECTIVE To understand the pathogens and their drugs resistance in general surgery department and provide rational suggestion of antibiotics use for clinic treatment.METHODS A total of 158 cases with nosocomial infection among the general surgery department inpatients from Jun 2006 to Oct 2008 were retrospectively analyzed and summarized.RESULTS The common nosocomial infection sites were the lower respiratory tract,gastrointestinal tract,urinary tract and surgical sites.The G-bacilli of nosocomial infections in turn were Escherichia coli(18.02%),Acinetobacter baumannii(11.26%),Pseudomonas aeruginosa(7.66%),and Klebsiella pneumoniae(4.50%).The main G+cocci were Staphylococcus aureus(21.62%),Enterococcus faecium(5.86%)and E.faecalis(3.15%)in turn.In G-bacilli,the sensitivity to imipenem was the highest from 58.82% to 100.00%.The sensitivity to amikacin were more than 70.00% except A.baumannii,and to sulbactam/cefoperazone were more than 50.00% except Pseudomonas aeruginosa.In G+ cocci,the sensitivity to vancomycin of S.aureus and E.faecium was 100.00% and 84.62%.CONCLUSIONS Investigating the pathogens and their drug resistance in general surgery department is very important to prevent and control nosocomial infections.

ObjectiveTo design a fast fourier transform (FFT) processor to meet the needs for high-speed and real-time signal processing. MethodsA 1 024-point, 32-bit, fixed, complex FFT processor was designed based on field programmable gate array (FPGA) by using radix-2 decimation in frequency(DIF) algorithm and pipeline structure in the butterfly module and ping-pong operation in data storage unit. ResultsWhen the primary clock was 100 MHz, 1 024-point FFT calculation took about 62.95us. The processor was fast enough for processing highspeed and real-time signals. ConclusionThe results provides reference value that theoretical study of the FFT algorithm can be applied in the adaptive dynamic filter of ultrasonic diagnostic system and ultrasonic doppler flow measurement system.

The lack of effective in vitro infection model for hepatitis E virus (HEV) has greatly hindered the quantitative analysis of neutralizing titers of anti-HEV antibodies and human sera, thus impeding further studies of HEV-stimulated antibody responses and the immunological mechanisms. In order to improve this situation, the infection of HepG2 cells that are inefficient for HEV replication was continuously monitored until the viral load reached the limit of detection on day 13, the results of which confirmed the feasibility of using this cell line to establish the infection model. Then, neutralization assays of five anti-HEV murine monoclonal antibodies and serum samples collected from four HEV vaccine recipients (collected before and after vaccination) were performed by 96 multi-channel parallel infections, nucleic acid extraction, and qPCR. The results showed that the cell model can be applied for quantitative evaluation of the neutralizing capacity of different antibodies and antiserum samples from HEV vaccine recipients. In this study, we have successfully established a high-throughput in vitro HEV replication model, which will prove to be useful for the evaluation of HEV vaccines and studies of HEV epitopes.
Animals ; Antibodies, Viral ; analysis ; immunology ; Hepatitis Antibodies ; analysis ; immunology ; Hepatitis E ; immunology ; virology ; Hepatitis E virus ; chemistry ; immunology ; physiology ; High-Throughput Screening Assays ; methods ; Humans ; Mice ; Mice, Inbred BALB C ; Neutralization Tests ; methods ; Virus Replication

By combining interleukin2 (IL-2) with a tumor specific antibody, immunotherapy of tumors may become more effective in the future. Anti-GD2 single chain antibody directed to the extracellular domain of GD2 disialoganglioside can result in an antitumor response in some pateins with tumors expressing GD2. In this study, the fusion protein consisting of GD2 single chain antibody (ScFv) and IL-2(Ala125) was constructed. Anti-GD2 ScFv and IL-2 genes were obtained by PCR, then the ScFv-IL-2 gene was constructed by over lap PCR. The gene was inserted into the pMD18-T easy vector. Genes from pMD18-T -vector were inserted into expression vector pSE380. Recombinant expression vector was identified by restriction enzyme-cutting and then was transformed into BL21. SDS-PAGE and Western blot analysis confirmed that the transformed E. Coli BL21 could express ScFv-IL-2 fusion-proteins and the molecular weight is 43 kDa. The fusion protein was purified by affinity chromatograph and Sephacryl S-200HR then was identified through ELISA. The results show that the fusion protein retains the activities of both antigen binding and IL-2.
Antibodies ; genetics ; metabolism ; Antibodies, Monoclonal ; biosynthesis ; genetics ; Base Sequence ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Gangliosides ; immunology ; Humans ; Immunoglobulin Fragments ; biosynthesis ; genetics ; immunology ; Interleukin-2 ; biosynthesis ; genetics ; Molecular Sequence Data ; Recombinant Fusion Proteins ; biosynthesis ; genetics

This study sought to construct a recombinant vector that expresses anti-GD2/anti-CD16 bispecific single-chain antibody(sc-BsAb), and to assess its biological activities. The anti-GD2 gene and the anti-CD16 gene (NM3E2) were obtained using PCR amplification technique, and then the fusion gene was constructed by overlapping PCR. The sc-BsAb gene was subcloned into the pET-22b(+) plasmid from the pMD18-T easy vector by digestion with NcoI, Hind III restriction endonucleases, whose sites exist in both the vectors. Then the combinant plasmids were transferred into E. coli BL21 (DE3). The expression product in the periplasmic was analyzed by both SDS-PAGE and Western blot technique, then was purified with Ni2+ -NTA superflow affinity chromatography. It was demonstrated that the linker in the sc-BsAb fusion protein is SerGly4Ser. and the molecular is 53 KD.
Antibodies, Bispecific ; biosynthesis ; genetics ; Antibodies, Neoplasm ; biosynthesis ; genetics ; Base Sequence ; Cell Line, Tumor ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Gangliosides ; immunology ; HeLa Cells ; Humans ; Melanoma ; pathology ; Molecular Sequence Data ; Receptors, IgG ; immunology ; Recombinant Fusion Proteins ; biosynthesis ; genetics

Pyruvate dehydrogenase E1 component subunit beta-1 (PDHB-1) is a gene encoding the β-subunit of pyruvate dehydrogenase complex, which plays an important role in fruit acid accumulation. The aim of this study was to investigate the evolution characteristics of apple PDHB-1 family and its expression in apples with different acid contents. Bioinformatics analysis was performed using databases including NCBI, Pfam and software including ClustalX, MEGA, and TBtools. By combining titratable acid content determination and quantitative real-time PCR (qRT-PCR), the expression of this family genes in the peel and pulp of apple 'Asda' and 'Chengji No.1' with different acid content were obtained, respectively. The family members were mainly located in chloroplast, cytoplasm and mitochondria. α-helix and random coil were the main factors for the formation of secondary structure in this family. Tissue-specific expression profiles showed that the expression of most members were higher in fruit than in other tissues. qRT-PCR results showed that the expression profile of most members was consistent with the profile of titratable acid contents. In the peel, the expression levels of 14 members in 'Asda' apples with high acid content were significantly higher than that in 'Chengji No.1' apples with low acid content, where the expression difference of MdPDHB1-15 was the most significant. In the pulp, the expression levels of 17 members in 'Asda' apples were significantly higher than that in 'Chengji No.1' apples, where MdPDHB1-01 was the most highly expressed. It was predicted that PDHB-1 gene family in apple plays an important role in the regulation of fruit acidity.
Malus/metabolism* ; Fruit/genetics* ; Protein Structure, Secondary

【Objective】 To develop a new approach for the preparation of 0.7~0.8 hematocrit concentrated washed red blood cells(RBCs) for fetal anemia in utero transfusion and apply it in clinical. 【Methods】 The erythrocyte suspension and frozen stored erythrocytes within expiry date in Guangzhou Blood Center from March 2020 to February 2021 were taken to prepare concentrated washed RBCs. According to the derivation formula, corresponding weight of RBC preservation solution was added to obtain 0.7~0.8 hematocrit concentrated washed RBCs. Routine blood test data were statistically analyzed by single-sample t test, and P<0.05 was considered statistically significant. Qualified Rh-negative/ O-type 0.7~0.8 hematocrit concentrated RBCs within expiry date were used in clinical intrauterine blood transfusion. 【Results】 The hematocrit of concentrated washing RBCs prepared by the new approach could reach 0.7~0.8. The RBCs count (8.389 ±0.808)×1 0¹²/ L and hemoglobin content(233.730±15.498)g/L were higher while the erythrocyte count (0.732±0.469)×10⁹ /L and platelets count(26.000±26.276)×10⁹/L were lower than the normal values of adults. The mean erythrocyte volume(fL), hemoglobin content(pg) and concentration(g/L )were 88.123±6.359, 30.004±2.809 and 339.980±11.865, respectively, which were normal values of adults. Fetal anemia was significantly improved and the prognosis was good after intrauterine blood transfusion. 【Conclusion】 The 0.7~0.8 hematocrit concentrated washed RBCs prepared by the new approach is consistent with the special blood requirements during fetal anaemia transfusion, meets the clinical treatment standards, and can be applied in clinical.