Objective To evaluate the detection methods for β‐lactamase in 3 kinds of Staphylococcus aureus to provide the basis for clinical laboratories selecting the best detection method .Methods 40 strains of Staphylococcus aureus were selected .With the BlaZ gene detection result as the gold standard for β‐lactamase detection ,the detection performance of the penicillin zone‐edge deter‐mination ,cloverleaf assay ,nitrocefin‐disk were evaluated .Results 20 strains of Staphylococcus aureus were the BlaZ gene positive detected by PCR and 20 strains were negative .The sensitivity of the penicillin zone‐edge determination method ,cloverleaf assay and nitrocefin‐disk were all 100 .00% and the specificity were 100 .00% .Conclusion Three kinds of β‐lactamase detection method have better sensitivity and specificity .So different laboratory can choose one of the method to detect β‐lactamase of staphylococcus aureus according to the actual situation .

Objective To investigate the distribution of blaOXA-51-like genes and the clonal relation-ship among Acinetobacter baumannii strains isolated from three teaching hospitals in Guangzhou , China. Methods Fifty-two Acinetobacter baumannii isolates were genotyped by multilocus sequence typing (MLST).eBURST algorithm was performed to define clonal complexes (CCs).blaOXA-51-like genes were am-plified by using polymerase chain reaction ( PCR) and sequenced .Results MLST grouped the A.bauman-nii isolates into 5 existing sequence types (STs) and 7 new STs.STn4 carried allele G1 with a T→C muta-tion at the 3rd nucleotide site (nt3) on the gpi111 locus.STn5 carried allele A1, possessing A→C muta-tions at nt156 and nt159 on the gltA1 locus.ST195 and ST208 accounted for 69.2%of all isolates.Clonal relationship analysis showed that ST 195 and ST208 belonged to CC92.Fifty-one A.baumannii isolates car-ried OXA-66 and the rest one carried OXA-199.Conclusion A.baumannii strains that belonged to CC92 and carried OXA-66 were the predominant genotype circulating in Guangzhou , China.

Objective:To investigate the correlations between perfused lung volumes, visual scores (using perfusion SPECT/CT) and right-heart catheter (RHC) hemodynamic parameters in patients with chronic thromboembolic pulmonary hypertension (CTEPH).Methods:A total of 51 consecutive CTEPH patients (17 males, 34 females, age (59±12) years) in the First Affiliated Hospital of Guangzhou Medical University between March 2015 and July 2019 were retrospectively analyzed. All patients underwent lung perfusion SPECT/CT imaging and RHC examinations. Perfused lung volumes were determined using threshold-based (15%-85%) segmentation. Visual semiquantitative scoring in each lung segment was performed using Begic method. RHC hemodynamic parameters including pulmonary artery systolic pressure (PASP), pulmonary arterial diastolic pressure (PADP), mean pulmonary artery pressure (mPAP), pulmonary arteriolar wedge pressure (PAWP), pulmonary vessel resistance (PVR), cardiac output (CO), cardiac index (CI) were recorded. Spearman correlation analysis was used to evaluate the correlations between perfused lung volumes, visual scores and hemodynamic parameters.Results:There were significant correlations between perfused lung volumes (30%-70% threshold) and mPAP ( rs values: from -0.414 to -0.302, all P<0.05). Among them, perfused lung volumes under the threshold of 40% and 45% were moderately correlated with mPAP ( rs values: -0.414, -0.412, both P<0.05). Perfused lung volume (40% threshold) was moderately negatively correlated with PASP, PADP ( rs values: -0.402, -0.440, both P<0.05), and slightly negatively correlated with PVR ( rs=-0.352, P<0.05). Visual scores were slightly positively correlated with the PADP ( rs=0.311, P<0.05), while there was no correlation between visual scores and other RHC hemodynamic parameters ( rs values: from -0.201 to 0.275, all P>0.05). Conclusion:Perfused lung volumes based on threshold-based segmentation in lung perfusion SPECT/CT imaging can accurately reflect hemodynamic status and may provide useful information for severity assessment of CTEPH.

OBJECTIVE To compare the effects of different drying processing methods in the producing area on the quality of Peucedanum praeruptorum， and screen the optimal drying processing in the producing area. METHODS P. praeruptorum was processed by traditional drying in the sun， drying in the shade， and modern drying processing methods such as electric heating and blast drying， vacuum drying， infrared drying， and vacuum freeze drying. Technique for order preference by similarity to ideal solution （TOPSIS） method was used to perform the comprehensive quality evaluation using drying rate， water content， extract content， color chroma value， and the contents of 4 coumarins as indexes. RESULTS Under different drying processing methods， the drying rates of 12 samples of P. praeruptorum were 31.56%-40.10%； the moisture contents were 6.96%-8.58%， and the extract contents were 27.56%-43.10%； the color chroma values red green degree， yellow blue degree and brightness were 1.80-7.50， 19.90- 30.20， 46.90-59.90， respectively. The contents of umbelliferolactone， praeruptorin A， praeruptorin B and praeruptorin E were ≤ 0.05， 3.70-14.05， 0.72-2.37， 0.81-3.90 mg/g， respectively； and the total contents were 5.47-19.65 mg/g. The comprehensive score of P. praeruptorum was the highest under the condition of drying at 40 ℃ by electric heating and blast . CONCLUSIONS The drying method at 40 ℃ by electric heating and blast is the first choice for P. praeruptorum in the producing area.

【Objective】 To analyze the demographic characteristics of whole blood donors who responded to blood donation initiatives launched by our blood center, so as to formulate an efficient recruitment strategy and provide scientific reference for solving seasonal, structural and acute blood supply tensions in this region. 【Methods】 Such characteristics as age, gender, household registration, occupation, blood type, education level, number of blood donations, blood donation location and recruitment method of 21 934 whole blood donors who responded to donation appointments issued by our blood center during January 2019 to June 2020 were analyzed, and the corresponding recruitment strategy in this region was established. 【Results】 39.79% of respondents were 36~45 years old, 69.61% were males, 70.49% were non-local permanent residents, and 62.96% were with education background from junior high school to high school. Workers accounted for 36.57%, 400 mL-donation accounted for 56.87%, the percentage of blood type O reached 42.18%, and blood donors with 2~5 donations accounted for 70.27%. The proportion of blood donors from Songshan Lake area(23.46%) ranked the highest, and that from Shuixiang area the lowest (3.26%). 76.42% of donation recruitment were issued via SMS. 【Conclusion】 Blood donors 36~45 years old, with 2~5 donations, donated 400 mL blood, non-local registered male, ordinary employees with the education level of junior high school, technical secondary school or high school should firstly be considered. The targeted areas are the Songshan Lake area, the main urban area coastal areas and southeastern Dongguan near Shenzhen.The corresponding recruitment strategies should be adjusted based on needs and emergency level.