流式细胞术检测健康成年人淋巴细胞亚群

淋巴细细胞亚群在维持机体免疫功能中起重要作用,淋巴细胞亚群检测广泛应用于肿瘤、艾滋病和自身免疫病的诊断、治疗及预后。文献检索发现,淋巴细胞亚群检测受地区、年龄、性别及民族等因素影响,不同国家和地区应建立健康成年人淋巴细胞亚群参考值范围。现就流式细胞术检测健康成年人外周血淋巴细胞亚群做一综述。     

Flow cytometric analysis of the functional ability of neutrophils from patients with autoimmune neutropenia

Flow cytometry has been used to evaluate the functional ability of neutrophils and the expression of IgG Fc receptors (FcRII and FcRIII) in autoimmune neutropenia. Quantification of the neutrophil oxidative burst was made by assaying the production of 2′7′-dichlorofluorescein (DCF) from non-fluorescent 2′7′-dichlorofluorescin trapped within the cell, by flow cytometric analysis of cellular fluorescence. In the present study the DCF assay was used to examine the response of neutrophils to stimulation by opsonized and non-opsonized Staphylococcus aureus. In addition, the rate of uptake of S. aureus labelled with the red nuclear dye propidium iodide was determined. The presence of surface-bound immunoglobulin, which may affect the phagocytic capacity of the neutrophil, was also measured. No correlation between the neutrophil count and level of membrane-bound IgG or the rate of bacterial uptake was found. The studies were performed on twenty patients with autoimmune neutropenia, twelve with other autoimmune disorders and fourteen normal controls. The rate of uptake of bacteria was considered in relation to the expression of FcRII and FcRIII. Good correlation was found with the level of expression of FcRII, the major receptor for neutrophil activation, and the rate of uptake of bacteria (r = 0.64).     

The value of assessing cell proliferation in breast cancer

Using three methods to measure cell proliferation, namely DNA cell cycle; anti-proliferating cell monoclonal antibody (MAb) (Ki67, P145) analysis by flow cytometry; and the histological silver (argyrophilic) staining technique to visualize nuclear-organizing regions (AgNOR), twenty-two paired samples of primary breast tumour and axillary lymph node were analysed. The results showed variable levels of correlation between the methods used for the tumour group (r = 0.915, P <0.001 for Ki677 versus P145; r = 0.42, P <0.005 for percentage S/G2/M-phase versus P145; r = 0.16, P <0.5 for percentage S/G2/M-phase versus AgNOR; r = 0.400, P < 0.1 for Ki67 versus AgNOR). The lymph-node group showed slightly poorer correlations, yet involved nodes showed a consistently higher level of proliferation than non-involved nodes by all methods used. Overall, MAb binding of Ki67 or P145 was seen to be a good indicator of cycling cells, detecting G1-phase cells in addition to S/G2/M-phase cells indentified by the other methods used. However, no advantage was found over the usual DNA flow cytometric analysis of cells, which had clear prognostic value. AgNOR scores were found to be able to discriminate between diploid and aneuploid; and dividing and non-dividing cells, but areas of score overlap limited the application of this technique to that of a positive discriminator only.     

检测早期细胞凋亡的流式细胞术

探讨了采用多参数流式细胞术分析氧化应激造成的心肌细胞凋亡过程中线粒体膜电位的改变。应用荧光探针JC-l可敏感检测到这种改变，是一种检测早期细胞凋亡改变的理想手段。     

Rapid assay for pathogenic salmonella organisms by immunofluorescence flow cytometry

Multi-parameter flow cytometry was investigated for the rapid detection of specific serotypes of salmonellas (S. typhimurium and S. montevideo) labelled with fluorescent monoclonal antibodies, both in pure culture and in a typical food matrix (full-fat milk). In all cases, the method was accurate to levels of below 10⁴ target cells per ml for a total assay time of about 30 min. After 6 h non-selective enrichment in the presence of a 10 000-fold excess of competing micro-organisms (Escherichia coli) the corresponding detection limit was about 20 cells ml^?1. These results suggest that flow cytometry has significant potential for the detection of pathogenic micro-organisms in the food industry.     

Automated classification and visualization of fluorescent live cell microscopy images

Robotic, high‐throughput microscopy is a powerful tool for small molecule screening and classifying cell phenotype, proteomic and genomic data. An important hurdle in the field is the automated classification and visualization of results collected from a data set of tens of thousands of images. We present a method that approaches these problems from the perspective of flow cytometry with supporting open‐source code. Image analysis software was created that allowed high‐throughput microscopy data to be analysed in a similar manner as flow cytometry. Each cell on an image is considered an object and a series of gates similar to flow cytometry is used to classify and quantify the properties of cells including size and level of fluorescent intensity. This method is released with open‐source software and code that demonstrates the method's implementation. Accuracy of the software was determined by measuring the levels of apoptosis in a primary murine myoblast cell line after exposure to staurosporine and comparing these results to flow cytometry.     

应用流式细胞术检测大鼠心肌细胞缺氧/复氧后内质网应急引起细胞凋亡

利用流式细胞仪观察西洋参茎叶总皂甘通诱导大鼠心肌细胞后内质网应急引起细胞凋亡。选用原代培养心肌细胞,将心肌细胞分为正常细胞对照组,缺氧/复氧组和缺氧/复氧后加入西洋参茎叶总皂苷组。按照40mg/L,80mg/L,160mg/L浓度培养24h后,应用流式细胞仪采用Annexin-V/PI诱导凋亡。结果显示应用流式细胞仪检测最终浓度为160mg/L西洋参茎叶总皂苷凋亡率明显低于缺氧/复氧组。流式细胞仪检测由内质网应急诱导细胞凋亡对研究细胞凋亡的机理提供一种快速、准确检测方法。     

皮托静压管的流量测量及不确定度评估

本文介绍了皮托静压管的结构原理及使用场合,讨论了使用皮托静压管进行流量测量时的测量计算方法,分析了实际测量条件下不同因素对流量测量结果的影响,并对测量结果的不确定度进行评估.     

Combined flow cytometry and image cytometry of the same cytological sample

Flow cytometry and image cytometry, two measuring techniques in the field of analytical cytology, can be used sequentially on the same cytological sample. Cells stained with a fluorochrome for the determination of for example, DNA or RNA content are first analysed in suspension by flow cytometry. The results of the fluorescence analysis of the individual cells are presented after data processing as frequency histograms of the DNA or RNA content of all the cells of the sample. In these histograms certain cell populations such as those with an increased DNA content are defined and these are then selected for further investigation. This is achieved by sorting cells of interest into centrifugation buckets by means of electrostatic deflection of the droplets containing such cells. Sorted cell populations are then centrifuged on to glass slides and stained according to the acriflavine Feulgen–SITS staining procedure, a quantitative method for DNA and protein. Image cytometry of these stained cells is performed with a computer controlled television based image analysis system (LEYTAS). With this system abnormal cells with elevated DNA content or increased chromatin contrast are automatically detected, thereby eliminating almost all artefacts and normal cells. Subsequently detected objects are stored in grey-value memories after the automated analysis for visual examination by the cytologist. The possibilities of combined flow cytometry and image cytometry are illustrated in typical examples in the field of cervical, bladder and mammary cytology.     

Influence of blockage and upstream disturbances on the performance of a vortex flowmeter with a trapezoidal bluff body

Experimental investigations are conducted on vortex flowmeter with the differential wall pressure measurement method. The bluff body employed is trapezoidal in shape and water is used as the working fluid. Three different blockages (0.14, 0.24 and 0.3) are considered in this study. The performance of the vortex flowmeter is studied both under fully developed condition and in the presence of flow disturbances. The flow disturbance is created using 45° swirl generator and gate valve placed at different upstream distances. The performance of the flowmeter is also evaluated in the presence of a Laws Vanes flow conditioner placed downstream of the swirl generator. The blockage ratio of 0.3 is found to be the best among all the blockages studied under both disturbed and undisturbed conditions.     

Rapid estimation of bacterial antibiotic susceptibility with flow cytometry

Bacterial antibiotic susceptibility was rapidly estimated for Escherichia coli and Staphylococcus spp. by flow cytometry. This was achieved by measuring the uptake of a negatively charged membrane potential sensitive dye bis-(1,3-dibutylbarbituric acid) trimethine oxonol and observing changes in low-angle light scatter (excitation light scattered by up to 15°). Estimations of ampicillin, gentamicin and ciprofloxacin susceptibilities were possible within 2–5 h from a plate culture, depending on the species and antibiotic used. This includes the time necessary to establish steady-state growth in liquid culture.     

Natural gas flow computer with open architecture using intelligent instrumentation and field bus

A new approach to natural gas flow computer design is presented in this paper. The developed system runs on a personal computer and employs the state-of-the-art mathematical models for corrections of some aspects of fluid flow dynamics, as well as for compressible behavior of gaseous fluid considerations. Orifice plates were used as primary elements. Measurements were performed through intelligent sensors. Results of the system metrological tests are also presented.     

A novel scheme for fault detection of reciprocating compressor valves based on basis pursuit,wave matching and support vector machine

A scheme for fault detection of compressor valves based on basis pursuit (BP), wave matching and support vector machine (SVM) is presented. BP is applied to extract the main vibration component in the signal and suppress background noise. Wave matching is a new feature extraction method proposed in this paper. Instead of extracting features through commonly used indicators such as statistic measures or information entropy, wave matching extracts features by matching the vibration signal with parameterized waveform optimized by differential evolution (DE) algorithm. It only produces a small number of features and the features have clear physical meaning. SVM is employed in the fault classification because of its superiority in dealing with small sample problems. The results of real compressor valve signal analysis confirm that the proposed scheme can differentiate compressor valve faults with high accuracy and reliability.