Serological chemiluminescence immunoassay for the diagnosis of SARS-CoV-2 infection.

OBJECTIVE: Dynamic monitoring of the concentration variation of IgM and IgG in patients with SARS-CoV-2 infections and exploring their diagnostic value for coronavirus disease-19 (COVID-19). METHODS: A total of 15 patients with SARS-CoV-2 infection were enrolled as the COVID-19 group, and 50 patients were enrolled as the control group. The concentrations of SARS-CoV-2-specific antibodies (IgM and IgG) were detected by a chemiluminescence immunoassay (CLIA). RESULTS: According to the cutoff value recommended by the manufacturer (cutoff = 10 AU/mL), the sensitivity, specificity, Youden index (YI), positive predictive value (PPV), and negative predictive value (NPV) of IgM were 60%, 100%, 60%, 100%, and 89.29%, respectively; and 86.67%, 100%, 86.67%, 100%, and 96.15%, respectively, for IgG. We reassessed the cutoff value of IgM. When the cutoff value for SARS-CoV-2 IgM was 1.83 AU/mL, the sensitivity, specificity, YI, PPV, and NPV were 93.33%, 98%, 91.33%, 93.33%, and 98%, respectively. During dynamic monitoring of the concentrations of IgM and IgG in COVID-19 patients, we found the shortest times before a patient became IgM and IgG seropositive after symptom onset were 1.5 and 2 days, respectively. The longest times were 7 and 8 days, respectively. The positive rates of SARS-CoV-2 IgM and IgG both reached 100% in 8-14 days after symptom onset. CONCLUSION: The IgM cutoff value of 1.83 AU/mL for the diagnosis of COVID-19 was much better than the cutoff suggested by the manufacturer. SARS-CoV-2 infection can be ruled out if antibodies against SARS-CoV-2 are still undetectable 14 days after symptom onset.

Application of PBL combined with LBL in clinical teaching for international students / 现代临床护理

Objective To explore the effects of problem based learning(PBL)and lecture based learning(LBL)in the clinical teaching for international students.Method According to the different time for clinical teaching,107 international students were divided into control group(n=53)and experiment group(n=54):the former were given LBL and the latter the combination of PBL and LBL.The teaching effects were assessed by way of practical examination and questionnaires.Result The scores in the experiment group were significantly higher than those in the control group.Conclusion The combination of PBL and LBL in clinical teaching for international students can not only improve teaching effects but also win the recognition of international students at the same time, which is worth popularizing and applying in clinical teaching.

Antidepressant effect of curcumin in mice / 中国组织工程研究

BACKGROUND: The development of safe and powerful antidepressant agents from traditional Chinese herbs has become a hotspot in studies on anti-depression therapy. OBJECTIVE: To investigate the anti-depressive effect and possible mechanism of curcumin by behavioral and neurochemical procedures. DESIGN: Randomized grouping design and controlled experiment. SETTING: Depart, ment of Pharmacology, School of Basic Medical Sciences of Peking University.MATERIALS: This study was carried out in the laboratory of the Department of Pharmacology, School of Basic Medical Sciences of Peking University, between November 2003 and October 2004. A total of 240 male ICR mice were recruited. METHODS: The whole experiment was divided into 4 tests. ① Antagonism of reserpine-induced hypothermia: Totally 60 mice were randomly chosen and divided into 6 groups: normal control group, groups of various doses of curcumin (1.25, 2.50, 5.00 and 10.00 mg/kg), and positive control group (imipramine 10 mg/kg). Normal temperature of the mice was measured before experiment. The animals were given a single injection of reserpine (2.5 mg/kg). The mice were administered with drugs 18 hours later, namely, curcumin of different concentrations by gastric perfusion, groundnut oil (0.1 mL/10g by gastric perfusion) as well as imipramine (10 mg/kg by intraperitoneal injection). Rectal temperature was measured 60, 90, 120,150 and 180 minutes after administration, respectively. ② Potentiation of 5-hydroxytryptophan (5-HTP)-induced head twitches: animal grouping was the same as above, and the drug in positive control group was replaced by fluoxetine. The mice received gastric perfusion and the dose of curcumin given was the same as above. Groundnut oil and fluoxetine (10 mg/kg) and 5-HTP (70 mg/kg) were injected into the vein of the tail one hour later.The number of head twitches was counted within 5-10 minutes after 5-HTP treatment. ③ Antagonism of apomorphine-induced hypothermia: Mice grouping was the same as above; the drug in positive control group was replaced by imipramine. Curcumin was give as above at 4 doses, and groundnut oil and imipramine were also given. Large-dose apomorphine was injected subcutaneously (16 mg/kg). Rectal temperature was measured before injection, as well as 30 minutes and 60 minutes after injection. ④Determination of monoamine and metabolites: Mice grouping was the same as above. The drug in positive control group was replaced by imipramine.Curcumin was give as above at 4 doses, and groundnut oil and imipramine were also given. The content of monoamine and metabolites in the mice was measured with high performance liquid chromatography. ⑤ Dunnett's t test was used for comparison between groups.MAIN OUTCOME MEASURES: ① In reserpine-induced hypothermia test, the change of body temperature before and after administration. ② In 5-HTP-induced head twitches test, whether the times of head twitches were increased. ③ In apomorphine-induced hypothermia test, the change of body temperature after administration. ④ Effect of drugs on the content of monoamine.RESULTS: Totally 240 mice entered the result analysis. ① Experiment results of reserpine-induced hypothermia: Curcumin (5 mg/kg and 10 mg/kg)produced an antagonism against reserpine-induced hypothermia, and the results were significantly different from those in control group (P ＜ 0.05,P＜0.01). Curcumin of 10.00 mg/kg produced the similar effect compared as that of imipramine in positive control group. ② Results of 5-HTPinduced head twitches: Curcumin (5 and 10 mg/kg) could significantly increase the times of 5-HTP-induced head twitches (P ＜0.05, P＜0.01). ③Results of apomorphine-induced hypothermia test: 2.50, 5.00 mg/kg and 10.00 mg/kg of curcumin could significantly increase the content of 5-HTP, and 10 mg/kg of curcumin could significantly increase the content of norepinephrine and dopamine. There was significant difference from that in control group (P ＜ 0.05). By contrast, curcumin had no obvious effect on the content of metabolite 5-hydroxyindol acetic acid and 3,4-dihydroxyphenylacetic acid. Imipramine of 10 mg/kg as the positive control drug could significantly increase the content of 5-hydroxyindol acetic acid and norepinephrine (P＜0.05).CONCLUSION: Curcumin has an antidepressant effect and the effect exerted may be related to monoaminergic neurotransmitter system.