We aimed to establish a rat TR model to further investigate the mechanisms of right heart remodeling and organ damage induced by TR. Intervention group rats (n = 6) underwent coronary stent system implantation via transjugular approach. The control group (n = 6) underwent the same procedure, except for coronary stent implantation. All rats survived at 8 weeks follow-up postoperatively. TR occurred immediately after the implantation of coronary stent in the intervention group. The right ventricular fractional area change (FAC) decreased by 33.9

Objective Aortic dissection (AD) is a fatal cardiovascular emergency that is predominantly induced by long-term uncontrolled hypertension.Materials and methods The mouse AD model was established by combining β-aminopropionitrile with angiotensin II. The incidence rate, rupture rate, and survival status of the mice were evaluated. The structural damage of the aorta was observed using tissue staining technology, the extracellular matrix status, and macrophage pyroptosis were evaluated by immunofluorescence staining, the infiltration of inflammatory cells was detected by immunohistochemistry, the expression of pyroptosis-related molecules, and inflammatory factors was analyzed by Western blotting and enzyme-linked immunosorbent assay (ELISA). Cell proliferation was detected by EdU staining, and cell apoptosis was detected by flow cytometry.Results In the aortic tissues of AD model mice, the expression of APN, and the content of APN in the serum were significantly decreased. APN intervention can alleviate the thickening of the aortic media, rupture of elastic fibers, and degradation of the extracellular matrix. APN inhibits the proliferation, apoptosis, and phenotypic transformation of vascular smooth muscle cells (VSMCs). At the same time, it can inhibit the infiltration of neutrophils and macrophages and the inflammatory response. Underlying mechanism, it was found that APN inhibited NLRP3-mediated pyroptosis by reducing the release of inflammatory factors; this effect was dependent on the phosphorylation activation of AMPKα and APN receptor.Conclusion APN plays a protective role in AD. Its underlying mechanism is related to the activation of the AMPK pathway, which in turn inhibits macrophage pyroptosis and vascular inflammation. This study offers a new perspective for the pathological mechanism of AD.

Background: The diagnosis, treatment, and prognosis of early postoperative constrictive pericarditis (EPCP) have not been discussed in depth. The objective of this study was to devise and propose a management strategy for EPCP. Methods: In this study, constrictive pericarditis (CP) within 6 months after cardiac surgery was defined as EPCP, and patients were divided into two groups based on intraoperative findings: a parietal thickening group and a visceral thickening group. Results: A total of 20 patients were included in this study, and the incidence rate of recurrent pericardiectomy was 0.32% among all patients undergoing cardiovascular surgery. EPCP after valve surgery occurred in 85.0% of patients. Pleural effusion was the most common preoperative symptom, occurring in 90% of patients. Pericardial thickening occurred in the visceral layer in seven cases and in the parietal layer in 13 cases. There were no differences in comorbidities, C -reactive protein (CRP) level, or erythrocyte sedimentation rate (ESR) between the two groups. Most patients with visceral thickening (83.3%) needed cardiopulmonary bypass (CPB) assistance during surgery and had a longer hospital stay than those with parietal thickening (52.8 +/- 21.8 vs. 34.9 +/- 13.8 days, P=0.049). Central venous pressure (CVP) was decreased in all patients after pericardiectomy (24.9 +/- 6.96 vs. 8.9 +/- 2.92 cmH 2 O, P<0.001), and the cardiac function improved significantly in patients with parietal thickening [New York Heart Association (NYHA) grade >= III accounted for 28.6% of patients]. The long-term survival rate of patients with parietal thickening was 92.3% and that of patients with visceral thickening was 57.1%, and there was no significant difference between them (P=0.056). Conclusions: Recurrent episodes of chest tightness, pleural effusion, and elevated CVP within 6 months after cardiac surgery should be considered highly suggestive of EPCP. There are few points of difference between pericarditis with thickening of the parietal and visceral layers. After failure of conservative medical treatment, pericardiectomy results in significant improvements in cardiac function and quality of life, especially in patients with thickening of the parietal layer.

Achondroplastic dwarfism is a rare hereditary metabolic disorder associated with a higher incidence of cardiovascular disease.There are few epidemiological data and surgical experience of rheumatic valvular disease in this population.This report is the only one to date on mitral replacement in an achondroplastic dwarfism.In addition, our approach involves placing the mechanical aortic valve prosthesis upside down in the mitral position.The 10-year results show benefits, but intraoperative management, valve type, and anticoagulation regimen are real challenges.

BACKGROUND:Defecation delay is a common symptom in patients after tricuspid valve replacement (TVR). Previous studies have demonstrated that defecation delay was associated with worse clinical outcomes of critically ill patients. Our study aimed to investigate the incidence and risk factors of defecation delay in patients after TVR and its adverse clinical outcomes. METHODS:A retrospective study was conducted in 206 patients undergoing TVR under cardiopulmonary bypass from May 2005 to July 2021. According to the first postoperative defecation time after surgery, patients were divided into the delayed group (>3 days) and control group (≤3 days). Baseline characteristics and preoperative, intraoperative, and postoperative data were collected to investigate the clinical outcomes of defecation delay. RESULTS:Among the 206 patients, 51.9% (107/206) cases were classified into the defecation delay group. Univariate analysis showed that age (P = 0.043), preoperative platelets (PLT) (P < 0.001), cardiopulmonary bypass (CPB) time (P = 0.013), minimum rectal temperature (P = 0.042), and the use of prokinetic drugs (P = 0.015) were significantly different in the two groups. In addition, the perioperative adverse events in the defecation delay group were significantly higher than that of the control group. Logistic regression analysis indicated that the mortality of patients was associated with postoperative renal dysfunction (P = 0.047) and postoperative respiratory failure (P = 0.004) but was not associated with defecation delay (P > 0.05). CONCLUSION:Patients with defecation delay after TVR were more likely to appear adverse events, however, defecation delay was not associated with mortality after TVR.

BACKGROUND:As one of the most important members in clinical trials, the number of clinical research nurses (CRN) can't keep up with the growth of experimental projects, so it is urgent to build clinical research training and strengthen the background knowledge of nurses.AIM:To construct CRN training program based on position competence, accelerate the construction of CRN talent pool, and provide scientific guidance significance for CRN training.METHODS:Based on the position competence model, combined with literature research and qualitative interview results, the first draft was prepared of the CRN training program. Two rounds of correspondence with 16 experts were conducted using the Delphi method to determine the training program.RESULTS:The effective recovery rate of the expert correspondence questionnaire was 100% and the authority coefficients of the 2 rounds of experts were 0.826 and 0.895. Finally, 4 first-level indicators and determine 15 s-level indicators of training objectives. The training program included 4 first-level indicators, training requirements, content, methods, assessment and evaluation, 15 s-level indicators, and 74 third-level indicators.CONCLUSION:The CRN training program based on position competence is scientific and extendable, providing a basis for participation in CRN training.

Object:Knowledge about the risk factors of in-hospital mortality for acute type A aortic dissection (ATAAD) patients who received total arch procedure is limited. This study aims to investigate preoperative and intraoperative risk factors of in-hospital mortality of these patients.Methods:From May 2014 to June 2018, 372 ATAAD patients received the total arch procedure in our institution. These patients were divided into survival and death groups, and patients` in-hospital data were retrospectively collected. Receiver operating characteristic curve analysis was adopted to determine the optimal cut-off value of continuous variables. Univariate and multivariable logistic regression analyses were used to detect independent risk factors for in-hospital mortality.Results:A total of 321 patients were included in the survival group and 51 in the death group. Preoperative details showed that patients in the death group were older (55.4 ± 11.7 vs. 49.3 ± 12.6, P = 0.001), had more renal dysfunction (29.4% vs. 10.9%, P = 0.001) and coronary ostia dissection (29.4% vs. 12.2%, P = 0.001), and decreased left ventricular ejection fraction (LVEF) (57.5 ± 7.9% vs. 59.8 ± 7.3%, P = 0.032). Intraoperative results showed that more patients in the death group experienced concomitant coronary artery bypass grafting (35.3% vs. 15.3%, P = 0.001) with increased cardiopulmonary bypass (CPB) time (165.7 ± 39.0 vs. 149.4 ± 35.8 min, P = 0.003), cross-clamp time (98.4 ± 24.5 vs. 90.2 ± 26.9 min, P = 0.044), and red blood cell transfusion (913.7 ± 629.0 vs. 709.7 ± 686.6 ml, P = 0.047). Logistic regression analysis showed that age >55 years, renal dysfunction, CPB time >144 min, and RBC transfusion >1,300 ml were independent risk factors for in-hospital mortality in patients with ATAAD.Conclusion:In the present study, we identified that older age, preoperative renal dysfunction, long CPB time, and intraoperative massive transfusion were risk factors for in-hospital mortality in ATAAD patients with the total arch procedure.

为了总结窦管交界(STJ)成形术治疗继发于升主动脉瘤或扩张所致主动脉瓣关闭不全(AR)的技术和疗效，探讨其手术适应证，我们于2008年1月至2019年6月对68例继发于升主动脉瘤或扩张所致AR的患者施行了STJ成形术，术前中度AR 46例，重度AR 22例，瓣环直径(23.6±1.4)mm，窦部直径(36.3±3.6)mm，升主动脉直径(53.6±10.2)mm，65例升主动脉置换人工血管直径为22～28 mm，其中24 mm、26 mm占54例，升主动脉成形术3例。同期手术包括全弓置换7例、二尖瓣和/或三尖瓣手术9例，冠状动脉旁路移植术(CABG) 5例。术中经食管超声心动图评估纠正AR效果，术后随访3～116个月，平均(36.7±18.3)个月。全组手术死亡2例，术毕经食管超声心动图评估AR轻度以下47例，无中度AR。51例在术后3～6个月随访期间超声心动图显示中度AR 5例，轻度或以下46例。随访超声心动图3年的42例患者中，中度AR 3例，轻度或以下AR 39例。STJ成形术对于继发于升主动脉瘤或扩张所致的AR有优良的早、中期效果，轻度反流的主要原因是瓣叶小体的局部增厚对合欠佳所致。判断AR是由单纯STJ扩张所致、选择合适的STJ缩小直径、以及均匀缩小STJ的直径是重要的手术技术和影响疗效的关键。

心脏肿瘤发病率极低,其中恶性心脏肿瘤约占10％ [1 - 2].恶性心脏肿瘤患者就诊多以胸闷、气促为首发症状,出现症状时一般已发展至中晚期.如治疗不积极,患者保守生存期仅 6～ 12 个月[3].积极外科手术虽能适当延长患者生存时间,但结局并不理想.

Objective:To analyze the therapeutic effects of reduction ascending aortoplasty (RAA) on bicuspid aortic valve (BAV) with ascending aortic dilatation.Methods:Two hundred and eight patients with BAV complicating ascending aortic dilatation who underwent aortic valve replacement (AVR) and RAA in Changhai Hospital were analyzed retrospectively from Jan 2006 to Dec 2015.The patients were divided into BAV group and tricuspid aortic valve (TAV) group according to the aortic valve.In BAV group, the patients were divided into <30 mm group and ≥30 mm group according to the target diameter of ascending aorta during the operation.Results:Post-operative mortality, complication rate, reoperation rate, and diameter of ascending aorta during follow-up had no significant difference between BAV and TAV group (all P>0.05).The diameter of ascending aorta during follow-up was significantly shorter and the degree of dilatation in ascending aorta was smaller at 5 and 9 years after operation in patients whose diameter of ascending aortas <30 mm during operation than those in patients whose diameter of ascending aorta ≥30 mm (all P<0.05).Conclusion:In patients with BAV complicating ascending aortic dilatation, BAV is not an adverse factor of RAA, and the medium-long term therapeutic effect is better if the target diameter of ascending aorta is controlled under 30 mm during RAA.

Accumulating evidence indicates that Voltage Dependent Anion Channel 1 (VDAC1) correlates with the initiation and progression of non-small cell lung cancer (NSCLC). However, the regulatory mechanism of VDAC1 in NSCLC remains unclear. Previous studies have reported that expression of miR-320a was decreased in human primary squamous cell lung carcinoma, which prompted us to investigate whether there is a functional link between decreased miR-320a and a high expression of VDAC1. In the present report, using computational analysis, we first show that miR-320a has a potential binding site on VDAC1 mRNA, and expression of miR-320a was decreased in NSCLC cell lines. Using gain-of-function and rescue experiments, we demonstrate that VDAC1 is a direct target of miR-320a in NSCLC cells, and miR-320a inhibits VDAC1 expression in NSCLC cells. Further we show that MiR-320a was significantly decreased in NSCLC tissues compared with adjacent non-tumor tissues, and MiR-320a level is negatively correlated with VDAC1 in NSCLC tissues by Pearson's correlation coefficient analysis. Moreover, using cellular ATP assay, we found that suppression of VDAC1 expression may inhibit cell proliferation and invasion of NSCLC by decreasing cell energy and metabolism. Importantly, we showed that ectopic overexpression of miR-320a blocked tumor cell proliferation and invasion, both in vitro and in vivo, through inhibiting VDAC1. Our results suggest that reduced expression of miR-320a facilitates the development of NSCLCs by increasing VDAC1 expression. We identified a novel regulatory mechanism between miR-320a and VDAC1, and miR-320a may serve as a tumor suppressor gene and a promising therapeutic target of NSCLCs.

Background: To investigate the correlation between consumption of whole grains and the risk of all-cause, cardiovascular disease (CVD), and diabetes-specific mortality according to a dose-response meta-analysis of prospective cohort studies.Methods: Observational cohort studies, which reported associations between whole grains and the risk of death outcomes, were identified by searching articles in the MEDLINE, EMBASE, and the reference lists of relevant articles. The search was up to November 30, 2015. Data extraction was performed by 2 independent investigators, and a consensus was reached with involvement of a third.Results: Ten prospective cohort studies (9 publications) were eligible in this meta-analysis. During follow-up periods ranging from 5.5 to 26 years, there were 92,647 deaths among 782,751 participants. Overall, a diet containing greater amounts of whole grains may be associated with a lower risk of all-cause, CVD-, and coronary heart disease (CHD)-specificmortality. The summary relative risks (RRs) were 0.93 (95% confidence intervals [CIs]: 0.91-0.95; P-heterogeneity<0.001) for all-cause mortality, 0.95 (95% CIs: 0.92-0.98; P-heterogeneity<0.001) for CVD-specific mortality, and 0.92 (95% CIs: 0.88-0.97; P-heterogeneity<0.001) for CHD-specific mortality for an increment of 1 serving (30g) a day of whole grain intake. The combined estimates were robust across subgroup and sensitivity analyses. Higher consumption of whole grains was not appreciably associated with risk of mortality from stroke and diabetes.Conclusion: Evidence from observational cohort studies indicates inverse associations of intake of whole grains with risk of mortality from all-cause, CVD, and CHD. However, no associations with risk of deaths from stroke and diabetes were observed.

BACKGROUND:MicroRNAs (miRNAs) are small noncoding RNAs that post-transcriptional regulate gene expression in a variety of cancers. Increasing evidences indicate that miR-30 expression is down-regulated in numerous human cancers including non-small cell lung cancer (NSCLC) which hypothesizes that miR-30 may play an important role in tumorigenesis. The aim of this study was to investigate the target gene of miR-30 and its roles in tumor growth of NSCLC.METHODS:Luciferase reporter assays were employed to validate regulation of a putative target of miR-30. The effect of miR-30 on endogenous levels of this target were subsequently confirmed via Western blot (WB). Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was performed to determine the expression level of miR-30 in NSCLC specimens and adjacent non-tumor tissues. MTT assays were conducted to explore the impact of miR-30 overexpression on the proliferation of human NSCLC cells.RESULTS:Both miR-30b and miR-30c (miR-30b/c) were found having target site in same region of Rab18 mRNA. Luciferase assays using a reporter carrying a putative miR-30b/c target site in the coding DNA sequence (CDS) region of Rab18 revealed that miR-30b/c directly targeted Rab18. Overexpression of miR-30b/c led to down-regulation of Rab18 in A549 and H23 cells at protein levels but not mRNA levels. Down-regulation of miR-30b/c and up-regulation of Rab18 protein levels were detected in NSCLC specimens compared with adjacent non-tumor tissues. Overexpression of miR-30b/c suppressed NSCLC cells growth. Knockdown of Rab18 by siRNA significantly inhibited the proliferation of NSCLC cells.CONCLUSIONS:We demonstrated that miR-30b/c was down-regulated in NSCLC specimens compared with adjacent non-tumor tissues. miR-30b/c directly targeted and down-regulated Rab18 expression and inhibited NSCLC cells proliferation. These data indicated that miR-30b/c could serve as a tumor suppressor gene involved in NSCLC pathogenesis.

Objective To study the regulatory effect of urocortin(UCN) on ischemia/reperfusion(I/R)-induced myocardial autophagy,so as to explore the myocardial protection mechanism of UCN.Methods Cardiac I/R model was established with rats and hypoxia/reoxygenation(H/R) model was also established with neonatal rat cardiomyocytes.The injury was created by ischemic/hypoxia for 1 h plus reperfusion/reoxygenation for 2 h,and UCN pretreatment was given 1 h before ischemia/hypoxia.The I/R or H/R-induced myocardial injury,myocardial autophagy and autophagy-related gene expression were observed 2 h after reperfusion/reoxygenation.Results UCN pretreatment greatly reduced I/R-induced myocardial damage by decreasing the infarct size,serum creatine kinase(CK) and lactate dehydrogenase(LDH) concentration,increasing the vitality of H/R cardiomyocytes in vitro,and reducing LDH level in the culture supernatant.Moreover,UCN pretreatment also inhibited H/R-induced myocardial autophagy by reducing the ratio of LC3BⅡ/LC3BⅠ and inhibiting expression of autophagy-related genes(Beclin1 and Bnip3).Conclusion UCN can inhibit I/R-induced myocardial autophagy,which may play an important role in the protection against I/R injury.

Objective To evaluate the safety and efficacy of radiofrequecy ablation for atrial fibrillation during minimally invasive mitral valve surgery via right thoracotomy.Methods From Jan.2008 to Dec.2011,30 patients underwent radiofrequecy Maze Ⅲ procedure for atrial fibrillation during mini-invasive mitral valve surgery(study group).Another 30 patients with atrial fibrillation undergoing mitral valve surgery through median sternotomy without Maze procedure during the same period were taken as controls.The pre-treatment data of the patients were matchable between the two groups.The study group received mitral valve repair/replacement and radiofrequecy Maze Ⅲ procedure for atrial fibrillation.The operative outcome,postoperative complication and elimination rate of atrial fibrillation were compared between the two groups.Results No patient in the study group was transferred to median sternotomy during operation,and there was no reoperation,prolonged incubation,failure of important organs,hemoglobinuria or death.Compared with the control group,the study group had significantly longer mean circulation arrest time and cardiopulmonary bypass time,significantly reduced chest drainage and blood transfusion volume,and significantly shortened hospital study(P0.05).The elimination rates of atrial fibrillation at immediately after operation,discharge and 6 months after operation were 96.7%,66.7% and 73.3% in the study group,and 50%,23.3% and 16.7% in the control group,respectively,with significant difference found between the two groups(P0.01).Compared with the control group,better heart function recovery was achieved in the study group at 6 month after operation.Conclusion Radiofrequecy ablation for atrial fibrillation during minimally invasive mitral valve surgery via right thoracotomy is safe and effective.Importantly,it does not increase risks and complications of surgery.The early and middle term effects are satisfactory.

Objective To determine the prevalence of CAD detectable by angiography and its relation to angina pectoris and CAD risk factors in patients with rheumatic aortic valve disease.Methods A consecutive series of 669 patients who underwent aortic valve replacement with rheumatic valve disease during 1998 and 2009 in Changhai hospital was retrospectively analyzed.The chi-square method was used to determine the relationship between angina pectoris and CAD,and logistic regression was employed to screen the CAD risk factors.Results(1)61 patients had angina pectoris and 40 of them had CAD,Pearsonχ2=161.4,P<0.001;(2)The independent coronary risk factors include age(OR=2.347),angina(OR=25.135),hypertension(OR=5.514)and hypercholesterolemia(OR=3.808).Conclusions(1)Angina pectoris was a predictive coronary risk factor in patients with RAVD,all the patients with angina pectoris should undergo CAG screening,but the absence of angina dose not excluded angiographically significant CAD;(2)Patients with CAD risk factors,including age≥50 years,hypertension,hypercholesterolemia,should receive CAG screening,while patients without the coronary risk factors can be excluded from CAG screening.

We sought to explore the pulmonary haemodynamic changes in rheumatic mitral stenosis patients with secondary pulmonary hypertension. The pulmonary artery resistance and compliance of 35 patients with rheumatic mitral stenosis and 12 controls without cardiopulmonary vascular disease were evaluated by using an improved method, which is based on making calculations with parameters obtained from right heart catheterisation. The results are as follows: (1) pulmonary artery compliance in patients with secondary pulmonary hypertension was significantly lower than that of the control group (P < 0.01); (2) linear correlation analyses showed that preoperative mean pulmonary artery pressure (mPAP) closely correlated with zero-pressure compliance in the mitral stenosis group

Objective To study the influence of age on quality of life(QOL) of patients with rheumatic valve disease after aortic valve replacement.Methods A total of 42 patients with rheumatic aortic valve disease who received aortic valve replacement in Changhai Hospital during March 2010 to Dec 2010 were prospectively studied.The patients were divided into 3 groups according their ages:(1) group A,45 years,(2) group B,≥45 years and 65 years,and(3) group C,≥65 years.QOL of patients was measured at baseline and at 3 months,6 months and 12 months after operation using Short Form 36-Item(SF-36) Health Survey.Wilcoxon matched pairs rank test was used to analyze the changes of patients' QOL after surgery,and repeated measurement was used to analyze the influence of age on QOL of rheumatic patients.Results(1) Four of the eight domains of the SF-36,including role-physical(RP),general health(GH),vitality(VT),and mental health(MH) were significantly improved in group A and C at 3 months after operation(P0.05),and all the eight domains were significantly improved at 6 and 12 months after operation(P0.05).For group B,four domains,including RP,GH,VT and social function(SF),were significantly improved at 3 months after operation(P0.05);all the domains but MH were significantly improved at 6 months after operation(P0.05),and all the 8 domains were significantly improved at 12 months after surgery(P0.05).(2) All the domains but GH had no significant difference between the 3 groups.The GH score in group A were significantly improved than that in group B and C(P=0.000).Conclusion The QOL of patients with rheumatic heart valve disease is improved after operation.Age is not a risk factor of QOL in patients with rheumatic heart valve disease after aortic valve replacement;younger patients seem to benefit more from the surgery for the GH score.

目的分析前列地尔注射液对冠状动脉旁路移植(CABG)术后血糖的影响。方法将45例冠心病合并糖尿病(需胰岛素治疗)接受CABG术的患者经匹配性别、纽约心功能分级、术前胰岛素用量和空腹血糖水平,分为三组:A组为对照组;B组经中心静脉缓慢注射前列地尔注射液10μg+生理盐水10ml,12h1次,术后连续48h;C组经中心静脉缓慢注射前列地尔注射液10μg+生理盐水10ml,6h1次,术后连续48h。测量术后2h、6h、12h、24h、48h血糖及48h内胰岛素使用总量,分析前列地尔对术后血糖的影响。结果三组术后血糖变化Greenhouse-Geisser,有统计学差异(F=24.607,P<0.001);组间比较:A组与B组无统计学差异(P=0.295);A组与C组有统计学差异(P=0.003);B组与C组有统计学差异(P=0.047)。三组术后48h胰岛素使用总量有统计学差异(P=0.010)。组间比较:A组与B组,B组与C组,均无统计学差异(P=0.101,P=0.134);A组与C组有统计学差异(P=0.003)。结论 (1)前列地尔注射液对CABG术后血糖控制有良好的效果;(2)前列地尔注射液持续给药(10μg+10ml生理盐水,6h1次)效果更佳。

BACKGROUND AND OBJECTIVE Lung cancer is a major worldwide health problem. The aim of this study is to establish a novel Chinese human lung adenocarcinoma cell line and examine its biological characteristics. METHODS Lung adenocarcinoma specimens were freshly resected during surgery. The tissues were incubated in vitro and the cell line was named Ch-Huang-1. The biological characteristics of the cells were investigated by light microscopy, chromosome analysis, and transplantation experiment. RESULTS Light microscopy revealed that cells from the primary tumor, Ch-Huang-1 cell line, and transplanted tumor possessed the characteristics of a malignant glandular epithelial tumor. The cell growth curve, doubling time, and mitotic index were also observed in vitro. Nuclear chromosome analysis revealed that the tumor was a subtriploid with a mode of 35-44 per cell. Tumor nodes were observed under the skin of nude mice by heterogenic transplantation. CONCLUSION The characteristics of the established cell line suggest that it is a newly established human adenocarcinoma cell line.