1.Determination of flavonoids in tender stem and leaf of Ampelosis prossedentata by differential spectrophotometry
Jieping QIN ; Shandan LIANG ; Cuiwei HE ;
Chinese Traditional and Herbal Drugs 1994;0(07):-
Object To develop a method for the determination of flavonoids from the tender stem and leaf of Ampelosis grossedentata (Hand. Mazz.) W. T. Wang, and for its quality control. Methods Differential spectrophotometry was used at the wavelength of (318?1) nm, while taking dihydromyricetin as index. Results The regression equation, within the range of the control concentration in 4 576~22 88 ?g/mL, was A=29 56 C+0 005 5, with a good linearity (r=0 999 8) between the absorbance and concentration. The average recovery rate was 100 8% and RSD was 1 9% (n=5). Conclusion The method is simple, reliable and easy to operate and suitable for the quality control of Chinese medicinal materials with a better reproducibility.
2.Estimation of expression of glycosylphosphatidylinositol-anchored protein in B lymphocytes for diagnosis of paroxysmal nocturnal hemoglobinuria.
Acta Academiae Medicinae Sinicae 2003;25(5):599-602
OBJECTIVETo estimate whether the expression of glycosylphosphatidylinositol (GPI)-anchored protein in B lymphocytes could be an indicator for detecting paroxysmal nocturnal hemoglobinuria (PNH).
METHODSFlow cytometry and two-color McAbs were used to detect CD59 expression in B lymphocytes and granulocytes of 92 clinical samples. The feasibility of the indicators for diagnosis of PNH was assessed.
RESULTSB lymphocytes from healthy individuals mainly showed a single population of cells strongly positive for CD59, as the percentage of CD59 expression was (96.3 +/- 1.2)%. In PNH patients, B lymphocytes showed decreased expression of CD59, as well as negative cells and partly-positive cells were observed, as the percentage of CD59 expression was 10.5%-92.3%. In 26 of 28 non-PNH anemia patients, CD59 expression in B lymphocyte was normal, and in the other 2 patients, CD59 expression were decreased (< 95%), but no negative cell peak was observed. The precision CV of CD59 in B lymphocyte assay is less than 4.4%, stained samples could be kept stable for 24 h, the CD59 in B lymphocyte assay was 100% in accordance with routine assay (CD59 in granulocyte assay). The sensitivity of the indicators (CD59 in B lymphocytes and granulocytes) was 100%, the specificity was 97.4%, misdiagnosis rate was 2.6%, the rate of failing to diagnosis was 0%, the rate of positive forecast was 87.5%, the rate of negative forecast was 100%, the accuracy was 97.8%.
CONCLUSIONSThe test of CD59 expression in B lymphocytes by flow cytometry was simple, accurate and reproduceable. It could be a good marker for diagnosis of PNH because of high sensitivity and specificity.
B-Lymphocytes ; metabolism ; Biomarkers ; CD59 Antigens ; blood ; Female ; Flow Cytometry ; Glycosylphosphatidylinositols ; biosynthesis ; Granulocytes ; metabolism ; Hemoglobinuria, Paroxysmal ; diagnosis ; Humans ; Male ; Membrane Proteins ; metabolism ; Sensitivity and Specificity
3.Assessment of atrial fibrillation inducibility based on epicardial mapping signals.
Journal of Biomedical Engineering 2020;37(3):487-495
Atrial fibrillation (AF) is the most common arrhythmia in clinic, which can cause hemodynamic changes, heart failure and stroke, and seriously affect human life and health. As a self-promoting disease, the treatment of AF can become more and more difficult with the deterioration of the disease, and the early prediction and intervention of AF is the key to curbing the deterioration of the disease. Based on this, in this study, by controlling the dose of acetylcholine, we changed the AF vulnerability of five mongrel dogs and tried to assess it by analyzing the electrophysiology of atrial epicardium under different states of sinus rhythm. Here, indices from four aspects were proposed to study the atrial activation rule. They are the variability of atrial activation rhythm, the change of the earliest atrial activation, the change of atrial activation delay and the left-right atrial dyssynchrony. By using binary logistic regression analysis, multiple indices above were transformed into the AF inducibility, which were used to classify the signals during sinus rhythm. The sensitivity, specificity and accuracy of classification reached 85.7%, 95.8% and 91.7%, respectively. As the experimental results show, the proposed method has the ability to assess the AF vulnerability of atrium, which is of great clinical significance for the early prediction and intervention of AF.