AIM:To investigate the roles of up-regulated inwardly rectifier potassium channel 2.1(Kir2.1)in macrophage activation and cardiac inflammatory injury,in order to clarify the mechanism of Kir2.1 regulation in inflam-matory injury and cardiac repair.METHODS:The RAW264.7 macrophages were activated by lipopolysacharide(LPS)and treated with Kir2.1 agonist zacopride or lentivirus-Kir2.1 overexpression(Kir2.1-OE).Macrophages were randomly divided into control,LPS,LPS+zacopride(or LPS+Kir2.1-OE),and LPS+zacopride+BaCl2 groups.The effects of Kir2.1-OE and AG490[Janus kinase 2(JAK2)inhibitor]on the JAK2/signal transducer and activator of transcription 3(STAT3)signaling pathway in macrophages were also investigated.The expression of CD86,interleukin-6(IL-6)and Kir2.1 in M1 macrophages was detected by RT-qPCR or immunofluorescence staining.The expression of JAK2/STAT3 molecules was detected by Western blot.The RAW264.7 macrophages were incubated with LPS,LPS+zacopride or LPS+zacopride+BaCl2 for 12 h,and then co-cultured with H9C2(2-1)cardiomyocytes for 48 h.The expression of Kir2.1,IL-4,IL-6,IL-1β,B-cell lymphoma-2(Bcl-2),Bcl-2-associated X protein(Bax),caspase-3,cleaved caspase-3,calcium/calmodulin-dependent protein kinase II(CaMKII)and p-CaMKII in cardiomyocytes was detected by Western blot.We fur-ther compared the effects of zacopride and KN-93,a known CaMKII inhibitor,on cardiac CaMKII.After being incubated with LPS for 12 h and changed the medium,RAW264.7 macrophages were co-cultured with H9C2(2-1)cardiomyocytes which was pretreated with KN-93.The cardiomyocytes were divided into control,LPS,and LPS+KN-93 groups.The ex-pression of CaMKII and p-CaMKII were detected by Western blot.RESULTS:Zacopride inhibited LPS-induced M1-type polarization of macrophages in a Kir2.1-dependent manner as showed by a significant decrease in CD86(M1-type marker)and IL-6(P<0.05).Zacopride or Kir2.1-OE inhibited LPS-induced activation of JAK2/STAT3 inflammatory signaling pathway in macrophages,with effects similar to the JAK2 inhibitor AG490.The H9C2(2-1)cardiomyocytes were co-cul-tured with M1-polarized macrophages(P<0.05).Zacopride inhibited M1 macrophage-induced inflammatory injury in car-diomyocytes,which was manifested as decreased expression of IL-1β and IL-6,increased expression of IL-4,and de-creased apoptosis.Zacopride also inhibited activation of CaMKII in a Kir2.1-dependent manner in H9C2(2-1)cells co-cultured with macrophages(P<0.05).CONCLUSION:Up-regulation of Kir2.1 may inhibit LPS-induced M1-type polar-ization of macrophages via inhibiting JAK2/STAT3 signaling pathway.Up-regulation of macrophage Kir2.1 may play a pro-tective role in cardiac repair after myocardial infarction by negative regulation of CaMKII signaling.

AIM:To investigate the roles of up-regulated inwardly rectifier potassium channel 2.1(Kir2.1)in macrophage activation and cardiac inflammatory injury,in order to clarify the mechanism of Kir2.1 regulation in inflam-matory injury and cardiac repair.METHODS:The RAW264.7 macrophages were activated by lipopolysacharide(LPS)and treated with Kir2.1 agonist zacopride or lentivirus-Kir2.1 overexpression(Kir2.1-OE).Macrophages were randomly divided into control,LPS,LPS+zacopride(or LPS+Kir2.1-OE),and LPS+zacopride+BaCl2 groups.The effects of Kir2.1-OE and AG490[Janus kinase 2(JAK2)inhibitor]on the JAK2/signal transducer and activator of transcription 3(STAT3)signaling pathway in macrophages were also investigated.The expression of CD86,interleukin-6(IL-6)and Kir2.1 in M1 macrophages was detected by RT-qPCR or immunofluorescence staining.The expression of JAK2/STAT3 molecules was detected by Western blot.The RAW264.7 macrophages were incubated with LPS,LPS+zacopride or LPS+zacopride+BaCl2 for 12 h,and then co-cultured with H9C2(2-1)cardiomyocytes for 48 h.The expression of Kir2.1,IL-4,IL-6,IL-1β,B-cell lymphoma-2(Bcl-2),Bcl-2-associated X protein(Bax),caspase-3,cleaved caspase-3,calcium/calmodulin-dependent protein kinase II(CaMKII)and p-CaMKII in cardiomyocytes was detected by Western blot.We fur-ther compared the effects of zacopride and KN-93,a known CaMKII inhibitor,on cardiac CaMKII.After being incubated with LPS for 12 h and changed the medium,RAW264.7 macrophages were co-cultured with H9C2(2-1)cardiomyocytes which was pretreated with KN-93.The cardiomyocytes were divided into control,LPS,and LPS+KN-93 groups.The ex-pression of CaMKII and p-CaMKII were detected by Western blot.RESULTS:Zacopride inhibited LPS-induced M1-type polarization of macrophages in a Kir2.1-dependent manner as showed by a significant decrease in CD86(M1-type marker)and IL-6(P<0.05).Zacopride or Kir2.1-OE inhibited LPS-induced activation of JAK2/STAT3 inflammatory signaling pathway in macrophages,with effects similar to the JAK2 inhibitor AG490.The H9C2(2-1)cardiomyocytes were co-cul-tured with M1-polarized macrophages(P<0.05).Zacopride inhibited M1 macrophage-induced inflammatory injury in car-diomyocytes,which was manifested as decreased expression of IL-1β and IL-6,increased expression of IL-4,and de-creased apoptosis.Zacopride also inhibited activation of CaMKII in a Kir2.1-dependent manner in H9C2(2-1)cells co-cultured with macrophages(P<0.05).CONCLUSION:Up-regulation of Kir2.1 may inhibit LPS-induced M1-type polar-ization of macrophages via inhibiting JAK2/STAT3 signaling pathway.Up-regulation of macrophage Kir2.1 may play a pro-tective role in cardiac repair after myocardial infarction by negative regulation of CaMKII signaling.

Objective: To analyze the epidemiological characteristics of coronavirus disease 2019 (COVID-19) local infections in Zhejiang Province during the period between March and May, 2022, so as to provide the evidence for COVID-19 control. Methods: The individual investigation data and field epidemiological investigation data of local COVID-19 cases in Zhejiang Province from March to May 2022 were extracted from the National Diseases Prevention and Control Information System of China. The temporal, spatial and population distribution, identification and booster vaccination of local COVID-19 cases were analyzed using a descriptive epidemiological method. Factors affecting the severity of clinical symptoms were identified among local COVID-19 cases using a multivariable logistic regression model. Results: A total of 289 local COVID-19 epidemics occurred in Zhejiang Province from March to May 2022, and all infections were caused by the Omicron variant. A total of 1 598 local COVID-19 infections were reported, including 672 confirmed cases (42.05%) and 926 asymptomatic cases (57.95%), and the 672 confirmed case included 614 mild cases (91.37%), 58 normal cases (8.63%), while no severe, critically ill or dead cases were reported. The mean duration of COVID-zero community, mean duration of COVID-19 epidemics and mean length to COVID-19 peak calculated according to 7 epidemics with 50 and more cases were (6.14±1.07), (13.43±4.39), (3.00±1.63) d, respectively. COVID-19 infection was predominantly detected in centralized quarantine sites (1 105 cases, 69.15%), and 843 cases completed booster immunization of COVID-19 vaccines (52.75%). Multivariable logistic regression analysis showed that age (with ages of 60 years and older as the reference, age of 6 to 17 years, OR=0.111, 95%CI: 0.024-0.508; age of 18 to 44 years, OR=0.341, 95%CI: 0.163-0.713) and booster COVID-19 vaccination (OR=0.219, 95%CI: 0.117-0.410) were protective factors for developing more severe clinical symptoms following COVID-19 infections. Conclusions All local COVID-19 infections were caused by Omicron variant in Zhejiang Province during the period between March and May 2022, and all cases had mild clinical symptoms. Preschool children, middle-aged and elderly residents and individuals that did not complete booster COVID-19 vaccination may had relatively more severe clinical symptoms following COVID-19 infections.

Background: The influencing factors of diabetic kidney disease (DKD) in Chinese patients with type 2 diabetes mellitus (T2DM) were explored to develop and validate a DKD diagnostic tool based on nomogram approach for patients with T2DM. Methods: A total of 2,163 in-hospital patients with diabetes diagnosed from March 2015 to March 2017 were enrolled. Specified logistic regression models were used to screen the factors and establish four different diagnostic tools based on nomogram according to the final included variables. Discrimination and calibration were used to assess the performance of screening tools. Results: Among the 2,163 participants with diabetes (1,227 men and 949 women), 313 patients (194 men and 120 women) were diagnosed with DKD. Four different screening equations (full model, laboratory-based model 1 [LBM1], laboratory-based model 2 [LBM2], and simplified model) showed good discriminations and calibrations. The C-indexes were 0.8450 (95% confidence interval [CI], 0.8202 to 0.8690) for full model, 0.8149 (95% CI, 0.7892 to 0.8405) for LBM1, 0.8171 (95% CI, 0.7912 to 0.8430) for LBM2, and 0.8083 (95% CI, 0.7824 to 0.8342) for simplified model. According to Hosmer-Lemeshow goodness-of-fit test, good agreement between the predicted and observed DKD events in patients with diabetes was observed for full model (χ2=3.2756, P=0.9159), LBM1 (χ2=7.749, P=0.4584), LBM2 (χ2=10.023, P=0.2634), and simplified model (χ2=12.294, P=0.1387). Conclusion LBM1, LBM2, and simplified model exhibited excellent predictive performance and availability and could be recommended for screening DKD cases among Chinese patients with diabetes.

Background: The influencing factors of diabetic kidney disease (DKD) in Chinese patients with type 2 diabetes mellitus (T2DM) were explored to develop and validate a DKD diagnostic tool based on nomogram approach for patients with T2DM. Methods: A total of 2,163 in-hospital patients with diabetes diagnosed from March 2015 to March 2017 were enrolled. Specified logistic regression models were used to screen the factors and establish four different diagnostic tools based on nomogram according to the final included variables. Discrimination and calibration were used to assess the performance of screening tools. Results: Among the 2,163 participants with diabetes (1,227 men and 949 women), 313 patients (194 men and 120 women) were diagnosed with DKD. Four different screening equations (full model, laboratory-based model 1 [LBM1], laboratory-based model 2 [LBM2], and simplified model) showed good discriminations and calibrations. The C-indexes were 0.8450 (95% confidence interval [CI], 0.8202 to 0.8690) for full model, 0.8149 (95% CI, 0.7892 to 0.8405) for LBM1, 0.8171 (95% CI, 0.7912 to 0.8430) for LBM2, and 0.8083 (95% CI, 0.7824 to 0.8342) for simplified model. According to Hosmer-Lemeshow goodness-of-fit test, good agreement between the predicted and observed DKD events in patients with diabetes was observed for full model (χ2=3.2756, P=0.9159), LBM1 (χ2=7.749, P=0.4584), LBM2 (χ2=10.023, P=0.2634), and simplified model (χ2=12.294, P=0.1387). Conclusion LBM1, LBM2, and simplified model exhibited excellent predictive performance and availability and could be recommended for screening DKD cases among Chinese patients with diabetes.