1.Effects of experiment-related factors on hematological parameters in SD rats
Jie CHENG ; Fei HUAN ; Suxiang JIN ; Wen QIAN ; Yihong ZHONG ; Yubang WANG
Chinese Journal of Comparative Medicine 2017;27(3):43-46
Objective To study the effects of experiment-related factors on hematological parameters in SD rats, analyze the data difference and causes, understand the effects of anesthetics and stress responses on the physiological aspects of animals, and to provide a reference for the standardization of animal welfare and compound toxicity testing methods.Methods According to gender (A), fasting time (B), anesthesia (C) and blood collection mode (D), SPF SD rats were divided into 24 groups.Blood samples were collected from each group.Then, red blood cell count, hemoglobin levels, white blood cell count and classification indicators were measured.Results The primary and secondary order of the factors affecting the white blood cell count was D > C > A > B, and the levels of white blood cell count of each factor were male rats > female rats, and venous blood > arterial blood, chloral hydrate > pentobarbital sodium > no anesthesia.The primary and secondary order of the factors affecting the white blood cell classification was C > D=A=B, and factors affecting the levels of white blood cell classification were chloral hydrate > pentobarbital sodium > no anesthesia.The primary and secondary order of the effects of the factors on the red blood cell count and hemoglobin level was C > D=A=B, and the levels of red blood cell count and hemoglobin level were pentobarbital sodium > chloral hydrate> no anesthesia.There was no significant difference in the blood indexes between the different fasting time groups.Conclusions There is no effect of fasting on hematological parameters, but there are differences in the blood parameters between arteries and veins.The effect of chloral hydrate anesthesia on the count and classification of white blood cells is greater than that of pentobarbital sodium.The effect of chloral hydrate anesthesia on the red blood cell count and hemoglobin level is greater than that of pentobarbital sodium.The two kinds of anesthesia methods have their own advantages and disadvantages.
2.Rapid detection of the bacterial drug susceptibility testing based on AIE technology
Lisha LAI ; Rentang DENG ; Lu ZHANG ; Yubang JIE ; Lingping XIE ; Zhihong HUANG ; Liming YIN ; Dujuan WANG ; Lijuan LI ; Junfa XU ; Lanfen PENG ; Wenjin FU
Chinese Journal of Laboratory Medicine 2023;46(11):1186-1192
Objective:Based on the principle that the aggregation-induced emission (AIE) fluorescent probe 6PD-DPAN could bind and aggregate with bacteria, and the fluorescence intensity could reflect the quantity of bacteria, a new method for rapid, convenient, and accurate bacterial drug sensitivity testing was established, which provided a basis for rapid and accurate clinical drug use.Methods:This was a methodological evaluation study. A total of 107 clinical isolates were collected from Houjie Hospital of Dongguan City from January to December 2022, among which 46 isolates were used for the establishment of the new method, and 61 isolates were used for methodological validation. The minimum inhibitory concentration (MIC) determined by broth microdilution method was used as the gold standard, and three antibacterial drugs, gentamicin, levofloxacin, and cefotaxime, were used as experimental drugs. The AIE plate was incubated for 4 hours, and the fluorescence intensity was measured every half an hour to draw a fluorescence change curve. The MIC results were compared with the CLSI breakpoints to determine the bacteria as sensitive, intermediate, or resistant. To simplify the detection process, the ratio of fluorescence intensity at 4 hours(R) was calculated, and the ROC curve was used to analyze the efficacy of R in determining bacterial growth and establish its cutoff value. The new method was used to determine the MIC of 61 clinical isolates, with broth microdilution method as the gold standard. The basic consistency, categorical consistency, very major errors, and major errors of the new method were analyzed, and the consistency between the two methods was determined by the Kappa test.Results:ROC curve analysis of the R after 4 hours of culture: The cut-off value was 3.0, with both sensitivity and specificity for determining bacterial growth being 100%. The median (interquartile) R for bacterial growth inhibition was 11.1 (8.6, 14.4); the median R-value for bacterial growth was 1.1 (1.0, 1.2). Compared to the gold standard, the newly established method showed 100% (61/61) essential agreement in detecting MICs of 61 clinical isolates, with a categorical agreement of 96.7% (59/61). There were no very major or major errors, and the Kappa value was 0.94, indicating good consistency between the newly established method and the microbroth dilution method.Conclusions:This study successfully established a new method for bacterial drug sensitivity testing based on AIE technology, which could obtain satisfactory results within 5 hours, providing a basis for early precision drug treatment in clinical practice.