ObjectiveTo explore the molecular mechanisms by which serum containing Gegen Qinlian Tang （GQT） inhibits glycolysis and enhances chemotherapy sensitivity in 5-fluorouracil （5-FU）-resistant colorectal cancer （CRC） cells based on the cyclin-dependent kinase 16 （CDK16）/MYC proto-oncogene （MYC） pathway. MethodsHCT-116/5-FU cells were treated with different concentrations （5%， 10%， 20%， 30%） of GQT-containing serum. Cell viability and 5-FU sensitivity were assessed using the cell counting kit-8 （CCK-8） assay， and the experimental concentrations of 5-FU and GQT for subsequent experiments were determined. Cell proliferation and apoptosis under individual 5-FU， GQT， and combined 5-FU + GQT treatments were evaluated using 5-ethynyl-2′-deoxyuridine （EDU） staining and annexin V-FITC/PI double staining， respectively. Glucose consumption， adenosine triphosphate （ATP） production， and lactate levels were measured by colorimetric assays. Expression levels of glycolysis-related proteins， CDK16， MYC， and phosphorylated MYC were detected by Western blot. Co-immunoprecipitation （CoIP） was used to examine the protein interaction between CDK16 and MYC， and cycloheximide （CHX） treatment was applied to assess the effect of CDK16 overexpression on MYC protein stability. ResultsCCK-8 assays showed that 2.5 mg·L^-1 5-FU significantly inhibited HCT-116 cell viability in a dose-dependent manner. In HCT-116/5-FU cells， significant inhibition was observed only at 5 mg·L^-1 5-FU （P<0.05）， which was used for model establishment. Compared with 5-FU alone， addition of 5% GQT-containing serum significantly suppressed HCT-116/5-FU cell viability （P<0.05）， with stronger inhibition at higher serum concentrations. Thus， 5% GQT-containing serum was used in subsequent experiments. Compared with the control group， 5-FU， GQT， and 5-FU + GQT treatments all significantly reduced cell proliferation （P<0.05） and increased apoptosis （P<0.01）. The 5-FU + GQT combination showed superior inhibition of proliferation compared with 5-FU or GQT alone （P<0.01）， accompanied by more pronounced reductions in glucose consumption， ATP production， and lactate generation （P<0.01）. Additionally， compared with control， 5-FU， and GQT groups， the 5-FU + GQT group exhibited stronger suppression of MYC and its phosphorylated forms （P<0.01） and greater inhibition of glycolytic enzymes， including hexokinase 2 （HK2）， 3-phosphoinositide-dependent protein kinase 1 （PDK1）， lactate dehydrogenase A （LDHA）， and pyruvate kinase M2 （PKM2） （P<0.01）. CDK16， MYC， and MYC phosphorylation expression levels were significantly downregulated in the 5-FU + GQT group compared with the 5-FU group （all P<0.01）. MYC protein stability decreased in a time-dependent manner in the 5-FU + GQT group （P<0.05）， which was rescued by CDK16 overexpression （P<0.05）. ConclusionGQT significantly enhances the sensitivity of HCT-116/5-FU cells to 5-FU， potentially by inhibiting CDK16 and thereby reducing MYC-mediated glycolysis.

ObjectiveTo explore the molecular mechanisms by which serum containing Gegen Qinlian Tang （GQT） inhibits glycolysis and enhances chemotherapy sensitivity in 5-fluorouracil （5-FU）-resistant colorectal cancer （CRC） cells based on the cyclin-dependent kinase 16 （CDK16）/MYC proto-oncogene （MYC） pathway. MethodsHCT-116/5-FU cells were treated with different concentrations （5%， 10%， 20%， 30%） of GQT-containing serum. Cell viability and 5-FU sensitivity were assessed using the cell counting kit-8 （CCK-8） assay， and the experimental concentrations of 5-FU and GQT for subsequent experiments were determined. Cell proliferation and apoptosis under individual 5-FU， GQT， and combined 5-FU + GQT treatments were evaluated using 5-ethynyl-2′-deoxyuridine （EDU） staining and annexin V-FITC/PI double staining， respectively. Glucose consumption， adenosine triphosphate （ATP） production， and lactate levels were measured by colorimetric assays. Expression levels of glycolysis-related proteins， CDK16， MYC， and phosphorylated MYC were detected by Western blot. Co-immunoprecipitation （CoIP） was used to examine the protein interaction between CDK16 and MYC， and cycloheximide （CHX） treatment was applied to assess the effect of CDK16 overexpression on MYC protein stability. ResultsCCK-8 assays showed that 2.5 mg·L^-1 5-FU significantly inhibited HCT-116 cell viability in a dose-dependent manner. In HCT-116/5-FU cells， significant inhibition was observed only at 5 mg·L^-1 5-FU （P<0.05）， which was used for model establishment. Compared with 5-FU alone， addition of 5% GQT-containing serum significantly suppressed HCT-116/5-FU cell viability （P<0.05）， with stronger inhibition at higher serum concentrations. Thus， 5% GQT-containing serum was used in subsequent experiments. Compared with the control group， 5-FU， GQT， and 5-FU + GQT treatments all significantly reduced cell proliferation （P<0.05） and increased apoptosis （P<0.01）. The 5-FU + GQT combination showed superior inhibition of proliferation compared with 5-FU or GQT alone （P<0.01）， accompanied by more pronounced reductions in glucose consumption， ATP production， and lactate generation （P<0.01）. Additionally， compared with control， 5-FU， and GQT groups， the 5-FU + GQT group exhibited stronger suppression of MYC and its phosphorylated forms （P<0.01） and greater inhibition of glycolytic enzymes， including hexokinase 2 （HK2）， 3-phosphoinositide-dependent protein kinase 1 （PDK1）， lactate dehydrogenase A （LDHA）， and pyruvate kinase M2 （PKM2） （P<0.01）. CDK16， MYC， and MYC phosphorylation expression levels were significantly downregulated in the 5-FU + GQT group compared with the 5-FU group （all P<0.01）. MYC protein stability decreased in a time-dependent manner in the 5-FU + GQT group （P<0.05）， which was rescued by CDK16 overexpression （P<0.05）. ConclusionGQT significantly enhances the sensitivity of HCT-116/5-FU cells to 5-FU， potentially by inhibiting CDK16 and thereby reducing MYC-mediated glycolysis.

[摘 要] 目的：探讨绿茶单体表没食子儿茶素没食子酸酯（EGCG）对大鼠肝癌发生过程中肠道菌群结构变化的影响。方法：建立二乙基亚硝胺（DEN）诱导的肝癌大鼠模型。将26只SD大鼠随机分成3组，分别为正常对照组、肝癌组和EGCG干预组。从实验开始第1天起，EGCG干预组每日给予EGCG（40 mg/kg）灌胃，正常对照组和肝癌组给予等量生理盐水灌胃，1次/日，持续至第20周。灌胃结束后，采集大鼠粪便样本，提取DNA，进行高通量16S rRNA V3-V4区测序；处死大鼠，取肝，观察肿瘤形成情况，并计算肝癌发生率。对测序数据进行生物信息学分析：经质控、聚类获得操作分类单元（OTU）表，据此计算α多样性指数（包括Observed species、Chao1、Shannon和Simpson指数），并进行β多样性分析。同时，对物种进行分类学注释，比较各组间菌群组成与丰度差异。结果： EGCG干预组大鼠（8只）肝脏肿瘤形成率明显低于肝癌组（10只）（50% vs 100%， P = 0.023），正常对照组（8只）大鼠无肿瘤发生。在肠道菌群方面，肝癌组操作分类单元（OTU）数量远低于正常对照组（P <0.001），而EGCG干预组OTU数量总体上高于肝癌组（P = 0.021）。α多样性分析显示，肝癌组Shannon指数低于正常对照组（P < 0.05）；此外，与肝癌组相比，EGCG干预组的Observed species指数、Chao1指数、Shannon指数和Simpson指数均显著提高（P < 0.05）。β多样性分析及主坐标分析（PCoA）表明，三组肠道菌群结构存在显著分离（PERMANOVA， R² = 0.3918， P = 0.001），其中EGCG干预组群落结构介于肝癌组与正常对照组之间，并更接近于正常对照组。肝癌组大鼠较正常大鼠肠道菌群中链球菌等潜在致病菌富集，丁酸产生相关菌（如丁酸球菌属、瘤胃球菌属等）丰度显著降低（P < 0.05）。相比之下，在EGCG干预肝癌发生过程中，大鼠肠道菌群结构相对稳定。厚壁菌门/拟杆菌门比值较肝癌组显著提高（P < 0.05），益生菌（如双歧杆菌属、乳杆菌属等）和丁酸产生相关菌（如丁酸球菌属）富集。结论：EGCG干预可降低DEN诱导的大鼠肝癌发生率，并有助于稳定肠道菌群结构，其作用可能与增加菌群多样性、促进益生菌及丁酸产生菌富集、恢复菌群平衡有关。

ObjectiveTo observe the prognosis effect of soluble programmed death ligand-1（sPD-L1） in treating patients with advanced lung adenocarcinoma treated with epidermal growth factor receptor-tyrosine kinase inhibitors（EGFR-TKIs） and the influence of Yiqi Yangyin Jiedu prescription. MethodA prospective cohort-controlled study was conducted to enroll patients treated with EGFR-TKIs in the first line of treatment，who were admitted to the Oncology Department of Longhua Hospital and Shanghai Chest Hospital from May 1^st， 2021 to June 30^th， 2023， and they were evaluated as non-progressive and identified with deficiency of Qi and Yin after one month of treatment. The patients were divided into an exposed group （EGFR-TKIs combined with Yiqi Yangyin Jiedu prescription） and a non-exposed group （EGFR-TKIs alone）according to whether or not they were treated with Yiqi Yangyin Jiedu prescription and were treated until disease progression， or death and intolerable adverse reactions occurred. The enzyme-linked immunosorbent assay （ELISA） was applied to detect the level of sPD-L1 in patients at the time of enrollment and disease progression，and Cox risk proportionality model was used to analyze the independent prognostic factors affecting disease progression of patients treated with EGFR-TKIs. ResultA total of 90 patients （39 in the exposed group and 51 in the non-exposed group） undergoing disease progression after EGFR-TKI treatment were enrolled. At the time of enrolment and after disease progression，the levels of serum sPD-L1 in the 90 patients were 12.06 （27.54） ng·L^-1 and 41.99 （62.93） ng·L^-1，respectively. Compared with that at the time of enrollment， the serum sPD-L1 level in the 90 patients was significantly increased after disease progression （P<0.01）. The serum sPD-L1 level in patients in the exposed group was 12.27 （24.78） ng·L^-1 and 29.57 （61.12）ng·L^-1 respectively at the time of enrolment and after disease progression. In the non-exposed group， patients had serum sPD-L1 levels of 11.81 （28.46） ng·L^-1 and 49.54 （74.12） ng·L^-1 respectively at the time of enrolment and after disease progression. Compared with that at the time of enrollment， the serum sPD-L1 level in the two groups of patients was significantly increased after disease progression （P<0.01）. In addition， compared with that in the non-exposed group， the sPD-L1 level in the exposed group was greatly reduced after disease progression（P<0.01）. Cox multifactorial analysis showed that sPD-L1 level and age at the time of enrolment were associated with patients' progression-free survival（PFS），and that low levels of sPD-L1 （<12.06 ng·L^-1） prolonged the PFS and reduced the risk of disease progression in patients treated with EGFR-TKIs compared with high levels of sPD-L1. ConclusionElevated sPD-L1 level is a poor prognostic factor for the long-term efficacy of EGFR-TKIs，and treatment with Yiqi Yangiin Jiedu prescription can down-regulate sPD-L1 level of patients treated with EGFR-TKIs.

ObjectiveTo investigate the clinical efficacy and safety of state-target formula Angelica and Safflower spot removal essence in the treatment of melasma. MethodsA randomized，double-blind，placebo-controlled parallel-group trial was conducted，selecting patients with Qi stagnation and blood stasis type of melasma who visited the dermatology outpatient department of Beijing Hospital of Integrated Traditional Chinese and Western Medicine from September 2022 to February 2023. In accordance with the double-blind principle，a random number table was generated to randomly divide the patients into an experimental group （50 cases） and a control group （50 cases）. The experimental group applied the Angelica and Safflower spot removal essence topically，while the control group applied a placebo topically，with continuous treatment for 8 weeks and a follow-up of 1 month. Melasma Area and Severity Index （MASI），Physician Global Assessment （PGA），patient self-assessment scoring，VISIA detection and scoring were performed before medication and on the first day after stopping medication，and all adverse events were recorded. ResultsIn a study involving 100 patients，87 cases were included in the analysis. The experimental group consisted of 45 cases，with 5 dropouts，and the control group had 42 cases，with 8 dropouts. The baseline data of the patients in both groups were consistent，with no statistically significant differences. After treatment，the total effective rate of the experimental group was 75.56% （34/45），significantly higher than the control group's 2.38% （1/42），and the difference was statistically significant （χ²=48.38，P<0.01）. Compared with before treatment，after treatment，the MASI score，VISIA image spot，brown spot，and red area score of the experimental group patients were significantly reduced （P<0.05，P<0.01），while there was no statistically significant difference in the control group patients. Compared with the control group after treatment，the experimental group showed more significant improvement （P<0.05，P<0.01）. VISIA image analysis showed that after 8 weeks of treatment，the experimental group showed significant improvement in surface spots，deep spots，and red areas，while the control group remained unchanged or showed an increasing trend. 42.22% （19/45） of the experimental group had a PGA score of 3 or below，while 88.89% （40/45） had a PGA score of 4 or below. 80.95% （34/42） of the control group had a PGA score of 5 or above，and the difference between the two groups was statistically significant （χ²=38.26，P<0.01）. There was no statistically significant difference in the recurrence rate and adverse reaction rate within one month between the experimental group and the control group. ConclusionThe state-target formula Angelica and Safflower spot removal essence is clinically effective and safe in the treatment of melasma.

The incomplete degradation of tumour cells by macrophages (Mϕ) is a contributing factor to tumour progression and metastasis, and the degradation function of Mϕ is mediated through phagosomes and lysosomes. In our preliminary experiments, we found that overactivation of NADPH oxidase 2 (NOX2) reduced the ability of Mϕ to degrade engulfed tumour cells. Above this, we screened out liquiritin from Glycyrrhiza uralensis Fisch, which can significantly inhibit NOX2 activity and inhibit tumours, to elucidate that suppressing NOX2 can enhance the ability of Mϕ to degrade tumour cells. We found that the tumour environment could activate the NOX2 activity in Mϕ phagosomes, causing Mϕ to produce excessive reactive oxygen species (ROS), thus prohibiting the formation of phagolysosomes before degradation. Conversely, inhibiting NOX2 in Mϕ by liquiritin can reduce ROS and promote phagosome-lysosome fusion, therefore improving the enzymatic degradation of tumour cells after phagocytosis, and subsequently promote T cell activity by presenting antigens. We further confirmed that liquiritin down-regulated the expression of the NOX2 specific membrane component protein gp91 phox, blocking its binding to the NOX2 cytoplasmic component proteins p67 phox and p47 phox, thereby inhibiting the activity of NOX2. This study elucidates the specific mechanism by which Mϕ cannot degrade tumour cells after phagocytosis, and indicates that liquiritin can promote the ability of Mϕ to degrade tumour cells by suppressing NOX2.

The incomplete degradation of tumour cells by macrophages(Mφ)is a contributing factor to tumour progression and metastasis,and the degradation function of Mφ is mediated through phagosomes and lysosomes.In our preliminary experiments,we found that overactivation of NADPH oxidase 2(NOX2)reduced the ability of Mφ to degrade engulfed tumour cells.Above this,we screened out liquiritin from Glycyrrhiza uralensis Fisch,which can significantly inhibit NOX2 activity and inhibit tumours,to elucidate that suppressing NOX2 can enhance the ability of Mφ to degrade tumour cells.We found that the tumour environment could activate the NOX2 activity in Mφ phagosomes,causing Mφ to produce excessive reactive oxygen species(ROS),thus prohibiting the formation of phagolysosomes before degradation.Conversely,inhibiting NOX2 in Mφ by liquiritin can reduce ROS and promote phagosome-lysosome fusion,therefore improving the enzymatic degradation of tumour cells after phagocytosis,and subse-quently promote T cell activity by presenting antigens.We further confirmed that liquiritin down-regulated the expression of the NOX2 specific membrane component protein gp91 phox,blocking its binding to the NOX2 cytoplasmic component proteins p67 phox and p47 phox,thereby inhibiting the activity of NOX2.This study elucidates the specific mechanism by which Mφ cannot degrade tumour cells after phagocytosis,and indicates that liquiritin can promote the ability of Mφ to degrade tumour cells by suppressing NOX2.

Objective:To explore the funding status and research hotspots of the National Natural Science Foundation of China (NSFC) for projects in the field of TCM for the prevention and treatment of heart failure.Methods:The research projects of TCM in the prevention and treatment of heart failure funded were retrieved from NSFC Big Data Knowledge Management Service Platform from January 1, 2010 to December 31, 2023. Excel 2022 software was used to analyze the data of the number of funded projects, the amount of funding, the supporting units and the regions. VOSviewer 1.6.20 software was used to analyze the co-occurrence of keywords with frequency≥3.Results:A total of 202 research projects were funded with a total funding amount of 89.8 million RMB, and the number and amount of projects showed a fluctuating upward trend. The funding categories were mainly general programs and youth science foundation projects. There were 42 supporting units involved, and TCM universities and colleges were the main recipients of funding. Regional distribution was uneven, mainly in Beijing, Shanghai, Guangdong and other regions. There were 17 secondary discipline codes involved, and the discipline categories were concentrated in Internal Medicine of TCM (H3108), Clinical Basis of Integrative Medicine (H3302) and Cardiovascular Pharmacology of Chinese Medicine (H3209). Therapeutic modalities covered compounding, monomers, proprietary Chinese medicines, and drug pairs, and research hotspots included aspects of myocardial energy metabolism remodeling, mitochondrial autophagy, macrophage polarization, endoplasmic reticulum stress, calcium homeostasis, ferroptosis, exosomes, micro-RNAs, and so on.Conclusion:NSFC has provided strong support to the research in the field of TCM for heart failure. In the future, the supporting units should pay attention to the interdisciplinary integration and development to promote the vigorous development of TCM.

Under the background of the Healthy China strategy， the integration of traditional Chinese medicine （TCM） into the public health emergency response system has become an important measure to enhance the capacity for coping with public health emergencies. In recent years， the role of TCM in responding to such emergencies has become increasingly prominent. Taking major emerging epidemics as an example， TCM has developed a rich theoretical system and practical experience in epidemic prevention and treatment over thousands of years， and has played a significant role in successive outbreaks with its unique advantages. Based on the concept of ''preventing disease before its onset'' and the theoretical framework of treatment based on syndrome differentiation， TCM has achieved remarkable results through early intervention and full participation in the integrated model of TCM and Western medicine， from severe acute respiratory syndrome （SARS） to corona virus disease-2019 （COVID-19）， in improving clinical symptoms and outcomes， reducing adverse reactions， and promoting recovery. From the perspective of the Healthy China strategy， this paper systematically reviews the historical development of TCM in epidemic prevention and treatment， with particular attention to recent epidemics such as SARS， influenza A （H1N1）， and COVID-19. It further examines the similarities and differences between TCM and Western medicine in responding to major emerging epidemics， as well as relevant policies related to TCM in epidemic prevention and control. In addition， it summarizes the existing problems in TCM's role in the prevention and treatment of major emerging epidemics， and explores measures to improve its rapid response capacity under the Healthy China strategy. This study not only provides a ''Chinese solution'' for the prevention and control of newly emerging infectious diseases worldwide， but also offers theoretical and practical references for strengthening the public health emergency response system， carrying strategic significance for promoting the modernization and internationalization of TCM.

Objective:To explore the effect of necroptosis inhibitor necrosulfonamide (NSA) on traumatic brain injury (TBI) mouse model and BV2 cell pyroptosis model and their mechanisms.Methods:(1) In vivo experiments: 50 mice were randomly divided into sham-operated group, TBI group, TBI+1 mg/kg NSA group, TBI+5 mg/kg NSA group, and TBI+10 mg/kg NSA group, with 10 mice in each group. TBI model was established using a modified Feeney's weight-drop method; 4 h after modeling, 90% corn oil, 1 mg/kg NSA, 5 mg/kg NSA, or 10 mg/kg NSA was administered into the mice, respectively. Mice in the sham-operated group only had circular bone window opened without being subjected to impact. At 48 hours after modeling, neurological function was evaluated by modified neurological function score (mNSS), serum lactate dehydrogenase (LDH) content was detected by LDH detection kit, contents of interleukin (IL)-18, IL-1β and tumor necrosis factor-α (TNF-α) in the brain tissues were detected by enzyme-linked immunosorbent assay (ELISA), and expressions and localizations of ionized calcium binding adaptor molecule 1 (IBA-1), cysteinyl aspartate specific proteinase-1 (Caspase-1) p20 and gasdermin D (GSDMD) in the injured parietal cortex were detected by double immunofluorescent staining. (2) In vitro experiments: BV2 cells were divided into control group, lipopolysaccharide (LPS)+adenosine triphosphate (ATP)+dimethyl sulfoxide (DMSO) group, LPS+ATP+5 μmol/L NSA group, LPS+ATP+10 μmol/L NSA group, and LPS+ATP+15 μmol/L NSA group. Cells in the latter 4 groups were induced by LPS+ATP to establish BV2 cell pyroptosis model, and incubated with 2 μL DMSO, 5 μmol/L NSA, 10 μmol/L NSA, and 15 μmol/L NSA for 1 hour, respectively; cells in the control group were cultured conventionally. Contents of LDH, IL-1β, IL-18, and TNF-α in the cell culture supernatant were detected by ELISA; pyroptosis was detected by calcein acetoxymethyl ester (CAM)/propidium iodide (PI) double staining; protein expressions of nucleotide binding domain-like receptor protein 3 (NLRP3), Caspase-1 p20, GSDMD, and N-terminal fragment of GSDMD (GSDMD-N) were detected by Western blotting. Results:(1) Compared with the TBI group, the TBI+1 mg/kg NSA group, TBI+5 mg/kg NSA group and TBI+10 mg/kg NSA group had decreased mNSS score and serum LDH content, decreased IL-1β and IL-18 contents in the brain tissues and number of Caspase-1 p20 + cells in the injured parietal cortex, successively, with significant differences ( P<0.05). Compared with the TBI group ([287.80±12.26] cells/mm 2), the TBI+1 mg/kg NSA group, TBI+5 mg/kg NSA group, and TBI+10 mg/kg NSA group had decreased number of Iba-1 +GSDMD + cells in the injured parietal cortex ([213.70±11.87] cells/mm 2, [205.30±9.15] cells/mm 2, [131.70±13.69] cells/mm 2),successively, with significant differences ( P<0.05). Compared with the TBI group, the TBI+5 mg/kg NSA group and TBI+10 mg/kg NSA group had significantly decreased number of Iba-1 + cells in the injured parietal cortex, and the TBI+10 mg/kg NSA group had significantly decreased TNF-α content in the brain tissues and number of GSDMD + cells in the injured parietal cortex ( P<0.05). Compared with the TBI group ([247.20±9.88] cells/mm 2), the TBI+10 mg/kg NSA group had significantly decreased number of Iba-1 +Caspase-1 p20 + cells in the injured parietal cortex ([181.70±9.37] cells/mm 2, P<0.05). (2) Compared with the LPS+ATP+DMSO group, the LPS+ATP+5 μmol/L NSA group, LPS+ATP+10 μmol/L NSA group, and LPS+ATP+15 μmol/L NSA group had decreased IL-18 content in the supernatant, successively, with significant differences ( P<0.05); and compared with the LPS+ATP+DMSO group, the LPS+ATP+10 μmol/L NSA group and LPS+ATP+15 μmol/L NSA group had significantly decreased contents of LDH, IL-1β, and TNF-α in the supernatant and ratio of PI +/CAM + cell counts ( P<0.05). Compared with the LPS+ATP+DMSO group (2.62±0.50), the LPS+ATP+10 μmol/L NSA group and LPS+ATP+15 μmol/L NSA group had significantly decreased Caspase-1 p20 protein expression (1.36±0.14, 1.32±0.07, P<0.05). Compared with the LPS+ATP+DMSO group (5.00±1.67), the LPS+ATP+5 μmol/L NSA group and LPS+ATP+15 μmol/L NSA group had significantly decreased GSDMD protein expression (1.42±0.26, 1.68±0.32, P<0.05). Compared with the LPS+ATP+DMSO group (2.28±0.24), the LPS+ATP+15 μmol/L NSA group had significantly decreased GSDMD-N protein expression (1.23±0.08, P<0.05). Conclusion:NSA can inhibit microglial pyroptosis after TBI by inhibiting the Caspase-1 p20/GSDMD pathway, thereby playing a neuroprotective role.