Objective To investigate the effect of MACC1 on RSL3-induced ferroptosis in colorectal cancer cells and explore its molecular mechanism.Methods MACC1 expression was detected in SW620,HCT116,LOVO and RKO cells using Western blotting.The effects of different concentrations of RSL3(an inducer of ferroptosis)or Fer-1(an inhibitor of ferroptosis)alone,or 10 μmol/L RLS3 combined with 10 μmol/L Fer-1,on viability of SW620 cells were examined using MTT assay.The survival of SW620 cells with mRNA interference of MACC1 was analyzed following treatment with RSL3,and RT-qPCR and Western blotting were performed to detect the changes in MACC1 expressions after RSL3 treatment at different concentrations and the changes in GPX4 expression after MACC1 knockdown.Flow cytometry and laser confocal microscopy were used to analyze the changes in ROS-induced lipid peroxidation in SW620 cells after MACC1 knockdown.Results SW620 cells had the highest MACC1 expression among the 4 colorectal cancer cell lines.Treatment with RSL3 significantly inhibited the viability of SW620 cells in a dose-dependent manner,while Fer-1 did not significantly affect the survival of SW620 cells.RSL3 alone reduced SW620 cell survival by 50%(P<0.01),and the combined treatment with RSL3 and Fer-1 caused no significant changes in cell survival(P>0.05).Treatment with RSL3 concentration-dependently suppressed MACC1 expressions at both the mRNA and protein levels in SW620 cells(P<0.01).MACC1 knockdown obviously enhanced the cytotoxic effect of RSL3,inhibited the expression of GPX4,and increased ROS-induced lipid peroxidation in SW620 cells(P<0.05).Conclusion MACC1 knockdown enhances RSL3-induced ferroptosis in cultured colorectal cancer cells by inhibiting the expression of GPX4.

Objective To investigate the effect of MACC1 on RSL3-induced ferroptosis in colorectal cancer cells and explore its molecular mechanism.Methods MACC1 expression was detected in SW620,HCT116,LOVO and RKO cells using Western blotting.The effects of different concentrations of RSL3(an inducer of ferroptosis)or Fer-1(an inhibitor of ferroptosis)alone,or 10 μmol/L RLS3 combined with 10 μmol/L Fer-1,on viability of SW620 cells were examined using MTT assay.The survival of SW620 cells with mRNA interference of MACC1 was analyzed following treatment with RSL3,and RT-qPCR and Western blotting were performed to detect the changes in MACC1 expressions after RSL3 treatment at different concentrations and the changes in GPX4 expression after MACC1 knockdown.Flow cytometry and laser confocal microscopy were used to analyze the changes in ROS-induced lipid peroxidation in SW620 cells after MACC1 knockdown.Results SW620 cells had the highest MACC1 expression among the 4 colorectal cancer cell lines.Treatment with RSL3 significantly inhibited the viability of SW620 cells in a dose-dependent manner,while Fer-1 did not significantly affect the survival of SW620 cells.RSL3 alone reduced SW620 cell survival by 50%(P<0.01),and the combined treatment with RSL3 and Fer-1 caused no significant changes in cell survival(P>0.05).Treatment with RSL3 concentration-dependently suppressed MACC1 expressions at both the mRNA and protein levels in SW620 cells(P<0.01).MACC1 knockdown obviously enhanced the cytotoxic effect of RSL3,inhibited the expression of GPX4,and increased ROS-induced lipid peroxidation in SW620 cells(P<0.05).Conclusion MACC1 knockdown enhances RSL3-induced ferroptosis in cultured colorectal cancer cells by inhibiting the expression of GPX4.

AIM:To investigate the molecular mechanism underlying ferroptosis induced by celastrol(Cel)in huamn pancreatic cancer cell line PANC-1.METHODS:The viability of PANC-1 cells was analyzed by MTT assay,and the effects of Cel on cell proliferation were analyzed using EdU and colony formation assays.Flow cytometry and fluores-cence microscopy were used to assess and observe changes in lipid reactive oxygen species(ROS)levels,respectively,while the levels of malondialdehyde(MDA),glutathione(GSH)and Fe2+were measured using specific kits.The protein expression of glutathione peroxidase 4(GPX4)was evaluated by Western blot,and GPX4 ubiquitination was measured by immunoprecipitation.RESULTS:It was found that the viability,proliferation and colony formation in PANC-1 cells de-creased gradually as the concentration of Cel increased.Addition of Cel alone to the cells reduced both cell rounding and viability,while treatment with ferrostatin-1(Fer-1)alone or in combination with Cel had no effect on either cell morpholo-gy or viability.Fluorescence staining of lipid ROS with BODIPYTM 581/591 C11 followed by flow cytometry analysis showed significantly increased levels of green fluorescence indicative of oxidized lipid ROS,which were further increased after treatment of the cells with Cel.Treatment of the cells with both Cel and Fer-1 reduced the green fluorescence and lip-id ROS levels.Treatment with Cel also increased the levels of MDA and Fe2+,relative to the controls,which reducing the levels of GSH,while addition of both Cel and Fer-1 to the cells restored the levels of MDA,Fe2+,and GSH to those of the control group.CONCLUSION:Treatment with Cel reduces the proliferation of pancreatic cancer cells by inducing fer-roptosis through promoting the ubiquitination and degradation of GPX4.

Objective To investigate spatial distribution and temporal trend of main water-soluble inorganic ions in PM_2.5 of Wuhan. Methods PM_2.5 samples were simultaneously collected at 5 sites in Wuhan from January 2017 to December 2017 (7 consecutive days per month). The main water-soluble ions in PM_2.5 were determined by weighing method and ion chromatography. The seasonal variations and spatial distribution differences were analyzed. Results The results showed that the mass concentration of PM_2.5 in Wuhan changed in different seasons. It was highest in winter, followed by spring and autumn, and lowest in summer. There were obvious seasonal changes in the mass concentrations and proportions of distinct ions. The concentrations of the four detected water-soluble inorganic ions were highest in winter. SO₄^2- had highest concentration and proportion, followed by NO₃^- and NH₄⁺, and Cl- was the lowest. In terms of spatial distribution, the total ion concentration and proportion was the largest in Wuchang and the lowest in Dongxihu. Conclusion The seasonal variation of main water-soluble inorganic ions in PM_2.5 was obvious, and the spatial distribution was also different in Wuhan.

AIM:This study aimed to explore the induction of ferroptosis in non-small-cell lung cancer(NSCLC)cells by tubeimoside II(TBMS II)and to elucidate the underlying molecular mechanisms.METHODS:H460 NSCLC cells were cultured in vitro.Cell survival rates were assessed by using MTT assays,and doses of TBMS II resulting in below 50%survival were selected for further experimentation.Cell migration was evaluated using Transwell assays and the effects of TBMS II on H460 cell proliferation were assessed by colony formation assays.Flow cytometry and fluores-cence microscopy were used to assess changes in lipid peroxidation(lipid ROS),and the levels of GSH,T-AOC,MDA,and Fe2+were measured using commercial kits.Protein levels of GPX4,SLC7A11,FTH1,NCOA4,P62,and LC3 were examined using Western blot.Changes in mitochondrial structure were detected by transmission electron microscopy,and immunofluorescence was used to assess LC3 co-localization of FTH1 and NCOA4,as well as co-localization of LC3 and NCOA4 with lysosomes.RESULTS:Compared with the control group,TBMS II dose-dependently reduced H460 cell via-bility,migration,and clone formation,accompanied by the appearance of vacuoles within the cells.TBMS II treatment al-so led to decreased GSH and T-AOC levels,while increasing the cellular contents of MDA,indicating oxidative stress.Ad-ditionally,there was a decrease in the expression of the antioxidant proteins SLC7A11 and GPX4 in the cells,while lipid ROS and Fe2+levels were increased in proportion to the TBMS II concentration.The ferroptosis inhibitor ferrostatin-1 re-versed cell death caused by TBMS II,suggesting ferroptosis induction.Furthermore,increasing the TBMS II concentra-tion resulted in an upregulation of the autophagy marker proteins LC3 II/LC3 I and P62,indicative of increased autopha-gy.TBMS II also affected mitochondrial morphology in the cells,as seen in reduced mitochondrial fluorescence intensity.Protein expression of NCOA4 increased with higher TBMS II concentrations,while that of FTH1 decreased.Co-localiza-tion of LC3 II with FTH1 and NCOA4,as well as the lysosomal association of LC3 II and FTH1,also increased in a dose-dependent manner.CONCLUSION:TBMS II induces ferritinophagy in H460 cells,leading to decreased cell viability and increased ferroptosis.

Objective To analyze the causes, characteristics and solutions of medical complaints against five tertiary general hospitals in Shandong province, and provide references for the hospitals to improve their quality of care and to build a harmonious relationship between doctors and patients. Methods A retrospective analysis method was used to analyze the causes, solutions and subjects of 1 049 medical complaints against five tertiary general hospitals in Shandong province from 2012 to 2015. Results Among the departments complained, orthopedics(165 cases, 15.7% ), and obstetrics and gynecology(136 cases, 13.0% )topped the rest. The causes of complaints mainly focued on the quality and effect of surgery(355 cases, 33.8% ), diagnosis and treatment(269 cases, 25.6% ), and service attitude(204 cases, 19.4% ). For outpatient/emergency departments, the patients mostly complained on " service attitude" (125 cases, 36.1% ), while the causes of complaints by inpatients were mainly " quality of surgery and effects" (332 cases, 44.8% ). In terms of the dispute solution pathways, consultation between doctors and patients became the most useful one(353 cases, 84.5%), and the third-party mediation approach(56 cases, 13.4% )also played an important role. Conclusions The hospitals should comprehensively strengthen their medical quality management, improve the quality of " service contact" and patient satisfaction. They are also recommended to establish a perfect complaint handling mechanism for higher patient satisfaction. The government should set up specialized courts for medical disputes and improve the efficiency of judicial solution of such disputes.

Objective To provide reference for service optimization of information suppliers and doctors through analyzing the residents'value cognition and utilization of online health information.Methods Questionnaires were distributed in June 2016 to 1 460 residents aged 18 or above and having experienced medical visits themselves or accompanying others in one year. They were surveyed to learn their health information cognition and utilization behavior. The data so acquired were subject to constituent ratio and Chi square test analysis. Results In terms of their use of online health information, 58.5% of the respondents would consult relevant information before medical visits, 64.3% would verify the doctor's diagnosis online following such visits. In case of any inconsistences, 28.2% of them would seek second opinion at another hospital. Statistical differences were discovered in the cognitive difference of residents of different sexes on "internet health information inquiry can relieve tension" , and in the utilization difference of residents of different ages and educational on " whether to consult online health information before medical visits" ( P<0.05). Conclusions The residents'value cognition of online health information is rational in general, but there are also some cognitive behaviors worthy of notice. Information conflicts may incur doctor-patient conflicts and repetitive medical visits. Stakeholders should ensure the professionalism and quality of the information providers. The doctors should master the communication skills and pay attention to the potential impact of online health information.

Objective To provide reference for bettering online health information supply and meeting residents' health needs by analyzing residents' access to and utilization rate of online health information. Methods 1 460 residents aged 18 years or above and having experienced medical visits themselves or accompanying others in one year were surveyed in June 2016. The survey covered their access to online health information and the utilization rate. χ2test, variance analysis, and important quadrant derivation model were used in the data analysis. Results 84.5% of the respondents used mobile phones as the most popular tool for accessing health information on the Internet, with more women than men. The importance quadrant analysis found that the residents have the highest utilization rate (72.6% ) of search engines, yet the reliability scoring of such engines was the lowest ( 62.8 ). Professional medical health websites scored the highest in reliability (81.8), yet the lowest utilization rate (2.1% ). Conclusions Search engines require stronger scrutiny to improve their information quality. Professional health and medical institutions'websites are encouraged to step up health information promotions, and health management Apps should be regulated in their development, to create convenient and reliable online health information platforms.

【Objective】 To study the CD4 T cell epitopes in Core and NS3 protein of genotype 1(GT1) and 6(GT6) of hepatitis C virus(HCV). 【Methods】 A total of 298 overlapping peptides(16-mer) spanning Core and NS3 protein of GT1 and GT6 HCV were synthesized. Peripheral blood mononuclear cells(PBMCs) from 17 HCV+ and 7 healthy blood donors were stimulated by peptide pools, followed by evaluating T cell response by IFN-γ ELISPOT, by which 21 peptides with positive results were found. These peptides were further applied to individually stimulate 20 HCV+ and 18 healthy PBMCs. The differences of responsive frequencies to the 21 positive peptides between the two study groups were compared. 【Results】 Pooled and individual peptide stimulation tests showed that HCV+ PBMCs were responsive to the stimulation of 5 peptides(GT1 NS31273-1288 and NS31315-1330; GT6 NS31033-1048, NS31087-1102 and NS31351-1366), with a responsive frequency ranging 18.9%-27.0%. In contrast, healthy PBMCs were not or low responsive(0%-4.0%) to these five peptides. The responsive frequencies were statistically different between the two groups(P<0.05). No reported epitopes in IEDB were found identical with these 5 peptides via sequence alignment. 【Conclusion】 Our study identified novel CD4 T cell epitopes in NS3 protein of GT1 and GT6 HCV, which has potential application value for the research and development of HCV vaccine.

【Objective】 To investigate the correlation of peripheral myeloid-derived suppressor cells (MDSC) with hepatitis c virus (HCV) infection. 【Methods】 109 voluntary blood donors who donated blood during February 2018 to September 2020 at Guangzhou Blood Center were recruited in this study. They were assigned to chronic hepatitis c (CHC) group (n=48), spontaneous clearance (SC) group (n=29) and healthy donors (control) group (n=32) according to the results of anti-HCV and HCV RNA tests. Blood samples were drawn from the participants and peripheral blood mononuclear cells (PBMC) were freshly isolated, followed by staining with fluorescently-labeled antibody against cell surface markers of MDSC, which were then applied to the detection of monocytic- (M) and polymorphonuclear (PMN)-MDSC by flow cytometry. Parameters for liver function including alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl transpeptidase (GGT), total bilirubin (TBIL) and direct bilirubin (DBIL) were also measured. One-way ANOVA tests were applied to compare the differences of M- and PMN-MDSC and liver function between three study groups. For pairwise comparisons, P values were adjusted for multiple comparisons by Bonferroni correction (Pc). 【Results】 The frequencies of M-MDSC (%) in CHC, SC and HC were 1.39±0.86, 0.85±0.63 and 0.57±0.23, respectively (P<0.01). Specifically, CHC presented significantly higher level of M-MDSC than SC (Pc<0.01) and control (Pc<0.05). There was no significant difference in the frequencies of PMN-MDSC among the three study groups (0.81±0.54 vs 0.65±0.40 vs 0.62±0.29, P>0.05). In addition, AST (34.4±19.2 vs 23.0±7.78 U/L) and GGT (40.8±31.4 vs 22.3±7.40 U/L) level were higher in CHC compared with control (Pc<0.05 and Pc<0.01, respectively). 【Conclusion】 The level of peripheral M-MDSC was significantly elevated in chronic HCV infected donors, which would related to the progression of chronicity after HCV infection.