ABSTRACT
ObjectiveExplore best upper respiratory tract sampling time of suspected novel coronavirus pneumonia cases. MethodsWe collected dates of patients from Hangzhou, Shenzhen, Jinhua city and so on who had the clear exposure history of a novel coronavirus pneumonia(COVID-19). We retrospected demographic data, exposure time, onset time, visiting time and positive time for novel coronavirus nucleic acid detection in respiratory specimens. There were 256 patients from January 20,2020-February 12,2020 from eight cities included in our study. 106 cases appeared symptoms before January 25th and 150 after. ResultsThere were 136(53.1%)male infected cases. The mean age of all patients was 43.80{+/-}14.85. The median time from exposure to onset was 5(3,8) days. The median time of the first time of positive nucleic acid detection was 11(9,14)days and mode number was 13. The median time from onset to the first time of positive nucleic acid detection was 6(4,8)days and mode number was 5. The time from onset to definite diagnosis was 5(3,7) days before January 25th while it was 7.5(5,10)days after which was significantly shorter before January 25th(U=3885.5,P<0.001). The time from exposure to definite diagnosis was 11(9,14)days and 11(9,14)days before January 25th and after and without significant difference. The time from exposure to definite diagnosis was 11(9,13)days in first-tier cities and 13(11,15)days in second and third-tier cities. The difference was significantly shorter of first-tier cities(U=1355.5, P=0.039). And also the time was short from visiting to definite diagnosis which was 2(2,3)days in first-tier cities and 3(2,4)days in second and third-tier cities but without significant difference(U=842.5, P=0.054). ConclusionsFrom our study we found that the best upper respiratory tract sampling time for novel coronavirus pneumonia suspects was 13days after exposure. The time from onset to definite diagnosis was shorter after January 25th. The patients were diagnosed faster in the first-tier cities after exposure.
ABSTRACT
Objective This study aimed to investigate the effect of splenic CD11clow CD45RBhigh dendritic cell (DC)derived from endotoxin tolerance (ET)mice on the expression of zinc finger protein A20 in acute liver failure (ALF)and to clarify the possible mechanism.Methods ET mice were modeled. CD11clow CD45RBhigh DC were isolated from spleen by magnetic activated cell sorting (MACS).One hundred and twenty-six healthy male BALB/c mice were randomly divided into four groups:control group (group A,n=6),ALF group (group B,n =40),normal CD11clow CD45RBhigh DC-treated group (group C,n=40),ET-CD11clow CD45RBhigh DC-treated group (group D,n=40).Mice in group B,C and D were injected with D-galactosamine (D-GalN)600 mg/kg and lipopolysaccharides (LPS)10 μg/mouse.Mice in group A were given the same volume of normal saline (NS).Half an hour after the D-GalN/LPS injection,mice in group C were treated with splenic CD11clow CD45RBhigh DC derived from normal mice (1 ×10 6/mouse,0.2 mL/mouse).Mice in group D were treated with splenic CD11clow CD45RBhigh DC derived from ET mice (1 × 10 6/mouse,0.2 mL/mouse).Mice in group A and B were given the same volume of 0.9% NaCl solution (0.2 mL/mouse).Alanine aminotransferase (ALT)and aspartate aminotransferase (AST)levels were measured at each time point.Liver histopathological changes were confirmed by hematoxglin and eosin methods.Expressions of tumor necrosis factor-α (TNF-α),nuclear factor-kappa B (NF-κB),and zinc finger protein A20 were measured by reverse transcriptase polymerase chain reaction(RT-PCR)and Western blot.One-way analysis of variance was used to compare means between groups.Normal distribution and homogeneity of variance were tested.LSD test was conducted in patients accorded with homogeneity of variance.Results ALT and AST levels increased 2 h after modeling in group B and peaked at 24 h,which were significantly higher than groups A (t = 31 .00, 11 .52,both P <0.05).ALT and AST levels also increased after 2 h after modeling and peaked at 24 h in group C and group D,which were both significantly higher than group B (t =14.60,26.43,both P <0.05).The mRNA levels and protein expressions of TNF-αand NF-κB in group B increased gradually and peaked at 12 h after D-GalN/LPS injection.Compared to that of group A,the differences were both statistically significant (t = 427.58,122.42,179.35 ,165 .98,all P < 0.05 ).The mRNA level and protein expression of zinc finger protein A20 in group B decreased gradually and reached the minimum at 12 h after D-GalN/LPS injection,which was statistically different compared to group A (t = 90.80, 160.43,both P <0.05).On the contrary,the levels of zinc finger protein A20 in group C and D increased gradually and peaked at 12 h after D-GalN/LPS injection.The expression level of zinc finger protein A20 in group D was significantly higher than group C (t = 11 .21 ,24.80,both P < 0.05 ).Conclusion Treatment of splenic CD11clow CD45RBhigh DC derived from ET mice contributes to liver protection against D-GalN/LPS-induced ALF.
