Objective To evaluate the limit of detection of eight enzyme-linked immunosorbent assay (ELISA) according to hospital grade assessment and ISO15189:2012.Methods According to the new health industry standard WS/T 514-2017:"Establishment and verification of detection capability for clinical laboratory measurement procedures",the limit of detection (LoD) was established,in the sameset of detection system,using two reagent lot,each lot for 5 consecutive days 4 consecutive days to assess the value of the concentration of five specimens were detected repeatedly,calculated the corresponding hit rate,then transform into probability units,and the corresponding concentration value production regression model,the hit rate of 95 ％ corresponds to the probability unit 1.645 substituted into the equation,the resulting concentration value was LoD estimates.The detection limit values were tested for 3 consecutive days of detection of two LoD concentrations near the declared concentration of the sample (diluted by the standard material) was detected 4 times repeatedly to calculate the positive result was greater than or equal to the percentage of LoD statement,greater than or equal to the critical value of 87％,then verified success.Results HBsAg:0.100 IU/ml,HBsAb:9.642 mIU/ml,HBeAg:0.666 NCU/ml,HBeAb:3.700 NCU/ml,HBcAb:0.786 IU /ml,HCV:0.506 NCU/ml,TP:2.236 mIU/ml and HIV:0.135 NCU/ml.The detection limit estimates were passed.Conclusion The verification limit of the verification project in the testing method and detection system of the laboratory meet the requirements Objective.

AIMTo investigate the antiarrhythmic effect of jumi (JM) extraction.

METHODSThe conventional antiarrhythmic methods were used.

RESULTSAdministration of JM extraction reduced the occurrence of ventricular fibrillation induced by chloroform in a dose-dependent manner in mice. Quinidine significantly decreased the number of ventricular premature beats and ventricular tachycardia, shortened the duration of arrhythmia in aconitine-treated rats. But JM extraction had no effect on aconitine-induced arrhythmia. Compared with control, arrhythmia score was lower in ischemia/reperfusion rats which pretreated with 2.0 g/kg of JM extraction.

CONCLUSIONJM extraction has obvious protection effects in chloroform- and ischemia-induced arrhythmia, but has no effect in aconitine-induced arrhythmia.

Animals ; Anti-Arrhythmia Agents ; therapeutic use ; Arrhythmias, Cardiac ; chemically induced ; drug therapy ; Female ; Male ; Mice ; Plant Extracts ; therapeutic use ; Rats ; Rats, Sprague-Dawley

Alanine Transaminase ; blood ; DNA, Viral ; blood ; Female ; Hepatitis B Antibodies ; blood ; Hepatitis B Surface Antigens ; blood ; Hepatitis B, Chronic ; virology ; Humans ; Male

AIMTo investigate the effect of interleukin-2(IL-2) on the cell contractility and calcium handling in cardiomyocytes during normoxia or anoxia/reoxygenation.

METHODSChemical anoxia introduced by Krebs-Henseleit(K-H) solution containing 10(-3) mol/L sodium dithionite was used in the enzymatically isolated rat ventricular myocytes. The video-tracking system and spectrofluorometric method were employed to verify the cell contraction and calcium handling of the single myocyte.

RESULTSDuring anoxia, the cell contraction, amplitude of calcium transient induced by electrical stimulation and Ca2+ release induced by caffeine were depressed while resting calcium level was elevated, but the activity of the L-type calcium channels were not changed. All the parameters could not return to the pre-anoxia level during reoxygenation. IL-2 at 2 x 10(5) U/L administrated during anoxia aggravated the effect of reoxygenation on cell contraction and the calcium handling.

CONCLUSIONCoexistence of IL-2 during anoxia aggravated the effect of reoxygenation on the cell contraction and calcium handling in the isolated rat ventricular myocytes, in which the reduced calcium release from sarcoplasmic reticulum was involved.

Animals ; Calcium ; metabolism ; Cell Hypoxia ; Cells, Cultured ; Heart Ventricles ; cytology ; Interleukin-2 ; pharmacology ; Male ; Myocardial Contraction ; drug effects ; Myocytes, Cardiac ; drug effects ; metabolism ; Oxygen ; metabolism ; Rats ; Rats, Sprague-Dawley ; Sarcoplasmic Reticulum ; metabolism

Aim To identify the potential biomarkers associated with carbon tetrachloride(CCl 4 )-induced a-cute hepatic injury in rats and explore the therapeutic effect of Hugan Tablets(HGT). Methods The model was established by intraperitoneal injection of CCl4 in oil(1 : 1,V/ V)with a dosage of 1 mL·kg - 1 body weight to rats once. The levels of aspartate aminotrans-ferase(AST),alanine aminotransferase(ALT),alka-line phosphatase (ALP ) and lactate dehydrogenase (LDH)in serum of rats were determined. Moreover,a proton nuclear magnetic resonance (1 H-NMR)based metabonomic approach in combination with multivariate data analysis was applied to demonstrate CCl4-induced acute hepatic injury metabolic perturbations in rat urine and feces and identify the corresponding metabolic bio-markers. The intervention effect of HGT was evaluated based on the changes of metabolic phenotype and po-tential biomarkers related to acute hepatic injury. Re-sults The levels of AST,ALT,ALP and LDH in ser-um of rats with acute hepatic injury were significantly reduced by administration of HGT,respectively. The disturbed metabolic state associated with CCl4-induced acute hepatic injury in rat urine and feces could be re-stored by HGT. Meanwhile,five potential biomarkers (2-oxoglutarate,citrate,creatinine,trimethylamine N-oxide,hippurate)in rat urine and three potential bio-markers(butyrate,glucose,uracil)in rat feces related to acute hepatic injury were reversed by administration of HGT,respectively. Conclusion HGT exerts pro-tective effects against CCl4-induced acute hepatic inju-ry in rats,which is probably mediated by regulation of tricarboxylic acid cycle and gut microbiota metabolism.

Objective To investigate the value of diffusion weighted imaging(DWI)in predicting delayed encephalopathy of the rabbits brain after carbon monoxide(CO)poisoning.Methods Sixty healthy rabbits were put into self-made poisoning cabinet and were poisoned by inhalation of CO.Aeration of CO was stopped when the rabbits became comatous,and the cabinet was kept airpoof for 6 h.The rabbits underwent MRI before poisoning,at 1 h,3 d,5 d,7 d,15 d,30 d,45 d,and 60 d after poisoning respectively. Axial and sagittal T_2WI,axial T_1WI and DWI were performed.In the rabbits that did not show symptoms of delayed encephalopathy,the observation was discontinued on the 60~(th)day.In the rabbit that showed the symptoms,the observation was discontinued on the 30~(th)——45~(th)day.The changing pattern of cortical ADC values before and after CO poisoning was observed and its relationship with delayed encephalopathy was investigated.Results In the group without delayed encephalopathy(15 rabbits),the ADC value at 1 h after poisoning[(7.58?0.36)?10~(-4)mm~2/s]decreased significantly compared with the pre-poisoning value[(8.02?0.35)?10~(-4)mm~2/s](q=0.4441,P0.05).In the group with delayed encephalopathy(15 rabbits),the ADC value at 1 h after poisoning [(7.40?0.32)?10~(-4)mm~2/s]decreased significantly compared with the pre-poisoning value[(8.08? 0.32)?10~(-4)mm~2/s](q=0.6728,P

OBJECTIVETo establish a multiplex RT-PCR-based reverse dot blot hybridization technique to detect influenza viruses.

METHODSObtain the HA nucleotide sequences of seasonal influenza H1N1, seasonal influenza H3N2, influenza H1N1 and human avian influenza H5N1 from GenBank. Design primers in conservative district and probes t in high variable region respectively, after analyzing the HA nucleotide sequences of influenza virus through the Vector NTI 9.0. Establish and optimize multiple RT-PCR system by comparing amplification efficiency and specificity at different primer concentrations. Establish the reverse dot hybridization system after optimizing the concentration of probes. To compare the sensitivity and specificity of this technique and the general RT-PCR Method through extracting the viral RNA of the mentioned influenza virus which are to be the reference substance.

RESULTSSuccessfully establish a multiplex RT-PCR-based reverse dot blot hybridization technique for detecting influenza viruses. This technique is 100-1000 times more sensitive than gel electrophoresis method, and it has a good specificity.

CONCLUSIONSuccessfully established multiplex RT-PCR-based reverse dot blot hybridization technique for detecting influenza viruses.

Humans ; Influenza A Virus, H1N1 Subtype ; genetics ; isolation & purification ; Influenza A Virus, H3N2 Subtype ; genetics ; isolation & purification ; Influenza A Virus, H5N1 Subtype ; genetics ; isolation & purification ; Influenza, Human ; diagnosis ; virology ; Nucleic Acid Hybridization ; methods ; Reverse Transcriptase Polymerase Chain Reaction ; methods ; Sensitivity and Specificity

Interleukin-2 (IL-2) therapy often results in potentially life-threatening side effects including hypotension. However, the mechanism has not been completely elucidated. In order to determine whether IL-2 modifies vascular tone, we investigated the effect of IL-2 on rat thoracic aorta rings and the underlying mechanisms. Effects of IL-2 on the contraction of high KCl and phenylephrine (PE) preconstricted rat thoracic aorta with or without endothelium were determined by organ bath technique. To explore the mechanism, nitric oxide synthase inhibitor L-N(G)-nitroarginine methyl ester (L-NAME), guanylyl cyclase inhibitor methylene blue, and cyclooxygenase inhibitor indomethacin were used. IL-2 (10-1000 U/ml) caused concentration-dependent relaxation of aorta rings preconstricted with PE (10 micromol/L) in endothelium-intact rings, but had no effect on KCl (120 mmol/L) preconstricted rings. Removal of the endothelium, or pretreatment with L-NAME (0.1 mmol/L) or methylene blue (10 micromol/L) or indomethacin (10 micromol/L), inhibited the relaxation of IL-2. The results indicate that the relaxation by IL-2 in rat aorta ring is endothelium-dependent and is possibly mediated by the NO-guanylyl cyclase pathway and cyclooxygenase-dependent pathway.
Animals ; Aorta, Thoracic ; drug effects ; physiology ; Endothelium, Vascular ; drug effects ; Endothelium-Dependent Relaxing Factors ; pharmacology ; Guanylate Cyclase ; metabolism ; In Vitro Techniques ; Interleukin-2 ; pharmacology ; Male ; NG-Nitroarginine Methyl Ester ; pharmacology ; Nitric Oxide ; metabolism ; Prostaglandin-Endoperoxide Synthases ; metabolism ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; drug effects ; Vasodilation ; drug effects ; Vasodilator Agents ; pharmacology

The aim of the present study was to explore the effect of nitric oxide (NO) on iron-induced toxicity in rat hearts. Langendorff perfused rat heart and enzymatically isolated cardiomyocytes were used. It was shown that lipophilic Fe-HQ reduced the contractile amplitude, velocity and end-diastolic cell length in the cardiomyocyte, while the left ventricular developed pressure (LVDP), +/-dp/dt(max), heart rate and coronary flow showed biphasic alterations, which increased in the first 2 min and then was followed by a decline in isolated perfused rat heart; the contents of lactate dehydrogenase (LDH) and creatine kinase (CK) in the coronary effluent and the malondialdehyde (MDA) in the myocardium were increased. L-arginine (L-Arg), an NO precursor, reduced the contractile amplitude and end-diastolic cell length in the cardiomyocyte; but reversibly increased LVDP, +/-dp/dt(max), and coronary flow in isolated perfused rat heart. Pretreatment with L-Arg aggravated the Fe-HQ-induced decrease in contractile amplitude, velocity and end-diastolic cell length in the cardiomyocyte; LVDP, +/-dp/dt(max), heart rate and coronary flow were significantly reduced in the perfused heart, and the levels of LDH and CK increased in the coronary effluent. In contrast, the NOS inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) blocked the Fe-HQ induced change in contractile amplitude, velocity and end-diastolic cell length in the cardio- myocyte; it inhibited the decrease in LVDP, LVEDP and +/-dp/dt(max), and reduced the LDH and CK. Removing endothelial cells in coronary vessels attenuated the increase in LVDP and +/-dp/dt(max) at the beginning of Fe-HQ perfusion. It is suggested that L-Arg aggravates the iron-induced cardiac dysfunction, NO can mediate the iron-induced toxicity in heart, and endothelial cells in coronary vessels play an important role in the early stage of the effect of iron.
Animals ; Arginine ; pharmacology ; Coronary Vessels ; cytology ; Creatine Kinase ; metabolism ; Endothelial Cells ; drug effects ; Heart ; drug effects ; Iron ; toxicity ; L-Lactate Dehydrogenase ; metabolism ; Malondialdehyde ; metabolism ; Myocardium ; metabolism ; Myocytes, Cardiac ; cytology ; NG-Nitroarginine Methyl Ester ; pharmacology ; Nitric Oxide ; metabolism ; Rats

OBJECTIVETo observe the effect of synchronous perfusion of specific respiratory chain complex IV inhibitor sodium azide (NaN3) in brain on rat ventromedial prefrontal cortex (mPFC) and acetylcholine (ACh) and choline (Ch) contents in hippocampal extra-cellular fluid, and establish the AD rat model induced by mitochondrial acute injury.

METHODThe synchronous dual-probe dual-channel brain microdialysis sampling technology was applied to synchronously perfuse modified Ringer's solution containing NaN3 (50 micro mol L-1) and neostigmine (2 micro mol L-1) into mPFC and hippocampus of conscious, freely moving normal rats, and continuously collect dialysates from different encephalic areas. Dynamic contents of ACh and Ch were determined by high performance liquid chromatography-post-column immobilized enzyme reactor-electrochemical process.

RESULTACh and Ch contents in mPFC extracellular fluid of normal rats were higher than that in hippocampus. During the process of perfusion, NaN3 could significantly reduce ACh in mPFC/hippocampal extra-cellular fluid, but remarkably increase Ch, and constantly inhibit the recovery of ACh and Ch contents in mPFC/hippocampus.

CONCLUSIONThe synchronous perfusion of NaN3in rat mPFC and hippocampus can injure functions of the cholinergic nerve projection area, and cause the acute AD model with ACh and Ch metabolic disorders. This model can be used in pathogenetic and pharmacological studies.

Acetylcholine ; metabolism ; Animals ; Choline ; metabolism ; Extracellular Fluid ; drug effects ; metabolism ; Hippocampus ; cytology ; Male ; Neurotransmitter Agents ; metabolism ; Perfusion ; Prefrontal Cortex ; cytology ; Rats ; Rats, Sprague-Dawley ; Sodium Azide ; administration & dosage ; pharmacology ; Time Factors