Objective To explore the methods of breeding ,reproduction and genotype of GJB2 knock -out (cCx26KO) mice and further study the critical role of GJB2 mutation in the onset of nonsyndromic hearing loss (NSHL) .Methods Two pairs of transgenic mice (Cx26loxp/loxp and Pax2 -Cre/+ ) were inbreeded to produce Cx26loxp/-_Pax2-Cre/+ ones ,female of which were used to mate with the male Cx26loxp/loxp ones to finally get the Cx26loxp/loxp_Pax2 -Cre/+ mice(cCx26KO) .The genotype was done by PCR and Agarose gel electro-phoresis using genome DNA extracted from the mice tails .The c-ABR was used to detect the hearing ability of the cCx26KO mice .Results Both breeding and reproduction of cCx26KO mice were successful .It was fruitful to obtain four genotype mice(Cx26loxp/loxp_ Pax2-Cre / + ,Cx26loxp / -_Pax2-Cre / + ,Cx26loxp/loxp ,Cx26loxp /-) by the breeding Cx26loxp / -_Pax2Cre / + and Cx26loxp/loxp mice .The results of breeding were met with the Mendel's law .The c-ABR revealed elevated response threshold around 95 dB SPL in cCx26KO mouse compared to the wild type ones ,which further validated the accuracy of the PCR method .Conclusion The PCR method is cor-rectly identified sub pups genotype and the female Cx26loxp/-_Pax2-Cre/+ mice mating with the male Cx26loxp/loxp ones is an effective way to obtain the cCx 26KO mice .

Objective By exploring the alteration of tissue plasminogen activator (t-PA) and tissue plasminogen activator inhibitor-1 (PAI-l) in plasma in Kawasaki disease (KD) patients to identify the pathophysiological mechanism of vascular damage and to detect the relationship between fibrinolytic system function and coronary artery lesion complications in Kawasaki disease patients. Method Plasma levels of t-PA, PAI-1 antigen were measured by enzyme-linked immunosorbent assay. Patients with KD were grouped into acute phase group, recovery phase group patients with coronary artery lesion group and non-coronary artery lesion group. Results Plasma t-PA and PAI-1 in acute phase and recovery phase groups were significantly higher than those in the healthy group (P

OBJECTIVETo investigate the effect of short and long term exposure to SiO2 nanoparticles on microRNA expression level in human bronchial epithelial cells(16HBE cells).

METHODSThe 16HBE cells were exposed to 5, 10, 15, 20, 25, 30 and 40 μg/ml SiO2 nanoparticles for 24 h to detect the cell viability by using CCK-8 assay. The inhibition rate of proliferation activity and half inhibitory concentration (IC50) were calculated. The 16HBE cells were exposed to 10 μg/ml SiO2 nanoparticles for 10 and 30 generations, named P10 and P30, and the control P0 was set. The cells were treated with SiO2 nanoparticles at 0, 1/4 IC50, 1/2 IC50 and IC50 concentration and μm-SiO2 at IC50 concentration for 24 h, and the control serum-free culture medium was set. Agilent miRNAs microarray chip was used to screen differentially expressed miRNAs in P10, P30 and P0 groups. The expression level of miRNA was detected by reverse transcription fluorescence quantitative polymerase chain reaction (qRT-PCR).

RESULTSThe inhibition rate of proliferation activity of 5, 10, 15, 20, 25,30,40 μg/ml group were (-3.33 ± 3.80)%, (20.40 ± 11.73)%, (39.08 ± 5.53)%, (55.10 ± 5.78)%, (66.42 ± 9.60)%, (71.67 ± 7.34)%, (81.43 ± 5.37)%, respectively; F=129.11, P<0.001. The IC50 (95%CI) was 18.35 (15.82-20.72) μg/ml. The expression level of miRNA-494-3p in P0, P10 and P30 were 1.00, 0.45 ± 0.08, 0.28 ± 0.07, respectively; F=60.77, P<0.001. miRNA-19a-3p were 1.00, 2.27 ± 0.45, 1.06 ± 0.19, respectively; F=30.05, P<0.001. miRNA-148b-3p were 1.00, 1.78 ± 0.29, 0.88 ± 0.19, respectively; F=30.23, P<0.001. Compared to control group, the expression level of miRNA-494-3p in 5, 10, 20 μg/ml SiO2 nanoparticles groups and 20 μg/ml μm-SiO2 group were 0.99 ± 0.04, 1.38 ± 0.19, 2.13 ± 0.14, 0.81 ± 0.25, respectively; F=57.03, P<0.001. miRNA-19a-3p were 0.91 ± 0.03, 1.12 ± 0.03, 0.53 ± 0.01, 0.86 ± 0.01, respectively; F=408.78, P<0.001. miRNA-148b-3p were 0.95 ± 0.02, 1.22 ± 0.00, 0.54 ± 0.02, 1.15 ± 0.04 respectively; F=264.14, P<0.001.

CONCLUSIONShort and long term exposure to SiO2 nanoparticles can affect the expression level of miRNAs in 16HBE cells. The expressions of miRNA-494-3p after long and short period exposure are different.

Cells, Cultured ; Epithelial Cells ; drug effects ; metabolism ; Humans ; MicroRNAs ; metabolism ; Nanoparticles ; chemistry ; Oligonucleotide Array Sequence Analysis ; Silicon Dioxide ; chemistry

Objective:To study the clinical significance of alveolar-arterial oxygen gradients (P A-aO 2) for late preterm and full-term infants with acute respiratory distress syndrome (ARDS). Methods:From January 2020 to June 2022, infants (gestational age ≥34 weeks) diagnosed with ARDS were admitted to the Neonatology Department of our hospital. The infants were assigned into the invasive group and the non-invasive group according to the ventilation mode. The infants with the same gestational age and diagnosed with neonatal wet lung were assigned into the control group. P A-aO 2 levels within 1 h after birth were compared among the three groups. The correlation of P A-aO 2 with ARDS, ventilation mode and duration were studied. Receiver operating characteristic (ROC) curve was used to determine the predictive value of P A-aO 2 within 1 h after birth for ARDS and the need of invasive ventilation. Results:A total of 36 cases were enrolled in the invasive group, 19 cases in the non-invasive group and 50 cases in the control group. Within 1 h after birth, P A-aO 2 in the invasive group was significantly higher than the non-invasive group and the control group ( P<0.05), and the non-invasive group higher than the control group ( P<0.05). Correlation analysis showed that P A-aO 2 within 1 h after birth in the invasive group was positively correlated with the duration of invasive ventilation and total mechanical ventilation ( r=0.601, P<0.001; r=0.504, P=0.002); P A-aO 2 before successful withdrawal of invasive ventilation was not correlated with subsequent non-invasive ventilation duration; and no correlation existed between P A-aO 2 within 1 h after birth and the duration of non-invasive ventilation in the non-invasive group. The area under the ROC curve for P A-aO 2 within 1 h after birth to predict ARDS was 0.875, with a sensitivity of 87.3% and a specificity of 72.0% at a cutoff value of 50.0 mmHg. The area under the ROC curve for predicting the need for invasive ventilation in infants with ARDS was 0.851, with a sensitivity of 80.0% at a cutoff value of 73.3 mmHg and a specificity of 75.0%. Conclusions:Late preterm and full-term infants have a higher risk of ARDS at P A-aO 2>50.0 mmHg within 1 h after birth. Infants with ARDS are more likely to require invasive ventilation if P A-aO 2>73.3 mmHg. The higher the level of P A-aO 2, the longer the duration of invasive ventilation and total duration of mechanical ventilation.