Objective To study the biological effects of (Janus Kinase-Signal transducers and activators of transcription,AK-STATs)path-way in hair cell apoptosis by analyzing the expression level of signal transducers and activators of transcription (STATS) of apoptotic HEI-OC1 cells line induced by oxidative stress injury.Methods Using different poisoning concentrations (0,20,40,60μM) of(Tert-Butyl hydroperoxide,T-BHP) built the apoptotic HEI-OC1 cells model while 0 μM was used as the control group.The apoptosis level at different poisoning concentration groups was detected by Annexin V-FITC/PI and the expression level of STATs mRNA by real-time quantitative PCR detecting system.Results The apoptosis rates in different contamination groups(0,20,40,60 μM) were 3.9％,7.4％,32.0％,and 91.2％,respectively.Compared with control group,STAT1 mRNA,STAT3 mRNA,STATS mRNA,and STAT6 mRNA expression levels in different poisoning concentration groups declined significantly (F=5 534.302,P＜0.01;F=146.038,P＜0.01;F=685.929,P＜0.01;F=516.11,P＜ 0.01).No statistically significant differences were found among the poisoning concentration groups (P＞0.05).Compared with the control group,the STAT2 mRNA expression levels changed significantly (F=1 259.148,P＜ 0.01).The STAT2 mRNA expression level in 20 μM contamination group decreased while 40,60 μM contamination group increased significantly (P＜0.01).No expression of STAT4 in HEI-OC1 cell was noted.Conclusion The JAK-STAT2 signal pathway has the biological effects on leading oxidative stress injury apoptosis and JAK-STAT1/STAT3/STAT5/STAT6 has the biological effect of inhibit oxidative stress injury apoptosis.

Objective:To explore the safety and efficacy of retrograde machine perfusion of kidneys from deceased donors.Methods:From January 1, 2020 to July 1, 24 renal transplant recipients underwent organ donation.All grafts were preserved by Kidney Transporter machines(LifePort). Through a random number table, they were divided into two groups of retrograde perfusion(RP group, 12 cases)and anterograde perfusion group(AP group, 12cases). The incidence of delayed recovery of kidney/graft function was compared between two groups.Results:During a follow-up period of 1 month, kidney resistance remained stable in RP group during perfusion.No primary non-function occurred in neither groups.No inter-group difference existed in the incidence of delayed graft function (3 in RP and 2 in AP, P=0.62). At all timepoints within 30 days, both groups had comparable values of urine output, serum creatinine, estimated glomerular filtration rate, cystatin c and blood urea nitrogen.RP group with a resistance index of <0.4 had numerically better kidney function than those with a resistance index of ≥0.4. Conclusions:This novel technique may be an effective and safe alternative for kidney preservation.

OBJECTIVE: To analyze the influence of signal transducers and activators of transcription 2(STAT2) on the apoptosis of oxidative stress-induced HEI-OC1 hair cells. METHODS: With random number table method,HEI-OC1 hair cells were divided into interference group and non-interference group. The artificial synthesis design targeted STAT2 small interfering RNA(siRNA) and opti-modified Eagle medium(opti-MEM) were added into the interference group, and only the opti-MEM was added into the non-interfere group. The 0, 20, 40, 60 μmol/L of tertiary butyl peroxide hydrogen(t-BHP) was added into the interference and non-interference group. Western blotting was used to detect the relative expression of STAT2 and cysteine protease(caspase)-3. The apoptotic rate of hair cells was detected by flow cytometry. RESULTS: In the interference group and non-interference group, the apoptotic rate of HEI-OC1 cells and the relative expression level of STAT2, Caspase-3 increased with the dose of t-BHP(P<0.01). The apoptotic rate of HEI-OC1 cells and the relative expression level of Caspase-3 in the interference group with 20, 40, 60 μmol/L of t-BHP were higher than that of the 20, 40 μmol/L group(P<0.01). The apoptotic rate of HEI-OC1 cells in the interference group was higher than those in the non-interference group with the same dose(P<0.01), while the relative expression level of STAT2 was lower than those in the non-interference group with the same dose(P<0.01). CONCLUSION: Inhibiting oxidative stress and STAT2 expression in hair cells can lead to aggravation of apoptosis. STAT2 has anti-apoptotic effect.

Background The chronic injury of the hematopoietic system caused by ionizing radiation (IR) is often ignored. The essential cause of this injury is the damage of hematopoietic stem and progenitor cells (HSPCs). Objective To explore the long-term effects of IR at different radiation doses and at different radiation fractions of the same radiation dose on HSPCs in the bone marrow of mice, and to provide a scientific basis for reducing the chronic damage to the hematopoietic system caused by IR. Methods A total of 16 male C57BL/6 mice aged 8-10 weeks were randomly divided into four groups that received different doses or fractions of total body X-ray irradiation, including 1.5 Gy×4 irradiation group (n=5), 3 Gy irradiation group (n=4), 6 Gy irradiation group (n=4), and non-irradiation group (n=3). Two months after irradiation, bone marrow cells from each mouse were collected and counted. The clone forming ability of bone marrow cells was analyzed by cobblestone area-forming cell (CAFC) assay. The proportion of HSPCs was measured by flow cytometry. The cell cycle of HSPCs was assessed by antigen identified by monoclonal antibody Ki 67 (Ki-67) and 7-amino-actinomycin D (7-AAD) double staining. The reactive oxygen species (ROS) levels of HSPCs were estimated with a 2,7-dichlorodihydrofluorescein diacetate (DCFDA) probe. The cellular senescence of HSPCs was evaluated with a 5-dodecanoylaminofluorescein di-β-D-galactopyranoside (C12FDG) probe. The expression of senescence related genes such as P16, P19, P21, and P27 was measured by real-time fluorescence quantitative PCR. Results There was no significant change in the numbers of bone marrow cells 2 months after different doses and fractions of radiation (P>0.05). The clone forming ability of bone marrow cells was significantly decreased after 3 Gy and 6 Gy irradiation when compared to non-irradiated mice (P<0.01). HSPCs responded inconsistently to different doses and fractions of irradiation. Overall, there was no significant change in long-term hematopoietic stem cells (LT-HSCs) proportion after irradiation (P>0.05), the proportions of hematopoietic progenitor cells (HPCs), hematopoietic stem cells (HSCs), short-term hematopoietic stem cells (ST-HSCs), and multipotent progenitors 2 (MPP2) increased after irradiation (P<0.05), and the proportions of LSK, MPP1, MPP3, and MPP4 cells decreased after irradiation (P<0.05); except for HPCs and MPP2, the proportion of HSPCs in G0 phase was decreased (P<0.05). The ROS production in HSPCs was increased significantly after 6 Gy irradiation (P<0.05), while the ROS levels after 3 Gy and 1.5 Gy×4 irradiation were similar to that of the non-radiation group (P>0.05). The cellular senescent proportion of HPCs, LSK, and HSCs increased after irradiation (P<0.05). The expression levels of senescence related genes P16, P19, and P21 in HSCs were significantly increased (P<0.05). Conclusion The responses of HSPCs in bone marrow to IR vary depending on doses and fractions of irradiation. Increased ROS production and cellular senescence may be involved in the damage process of HSPCs under radiation settings.