ObjectiveTo screen for the patients with metabolic dysfunction-associated fatty liver disease （MAFLD） among the physical examination population， to observe the characteristics of MAFLD patients， and to compare the differences in lifestyle between the MAFLD population and the non-MAFLD population. MethodsA cross-sectional study was conducted among 6 206 individuals who underwent physical examination in a physical examination institution in Beijing from December 2015 to December 2019， and according to the new diagnostic criteria for MAFLD， the examination population was divided into MAFLD group and non-MAFLD group. Based on body mass index （BMI）， the MAFLD group was further divided into lean MAFLD group （BMI<24 kg/m²） and non-lean MAFLD group （BMI ≥24 kg/m²）. Related data were compared between groups， including demographic indicators， education level， work pressure， physical measurement indicators， and lifestyles such as sleep， diet， and exercise. The independent-samples t test was used for comparison of normally distributed continuous data between two groups， the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups， and the chi-square test was used for comparison of categorical data between groups. ResultsOf all individuals in this study， 1 926 （31.1%） had MAFLD and 4 280 （68.9%） did not have MAFLD. Compared with the non-MAFLD group， the MAFLD group had significantly higher age （Z=-14.459， P<0.001）， proportion of male patients （χ²=72.004， P<0.001）， work pressure （χ²=7.744， P=0.005）， body weight （Z=-43.508， P<0.001）， BMI （Z=-47.621， P<0.001）， waist circumference （Z=-48.515， P<0.001）， hip circumference （Z=-42.121， P<0.001）， and waist-hip ratio （Z=-43.535， P<0.001）， as well as a significantly lower education level （χ²=33.583， P<0.001）. In terms of behavior， the MAFLD group had a significantly shorter sleep time （χ²=5.820， P=0.016） and a significantly faster eating speed （χ²=74.476， P<0.001）. In terms of diet， the patients in the MAFLD group consumed more high-sodium， high-sugar， and high-calorie diets （χ²=42.667， P<0.001） and low-fiber diet （χ²=4.367， P=0.008）. In terms of exercise， the MAFLD group had a significantly higher proportion of patients without exercise habits （χ²=10.278， P=0.001）. Further analysis showed that there were 202 individuals （10.5%） in the lean MAFLD group and 1 724 （89.5%） in the non-lean MAFLD group. Compared with the non-lean MAFLD group， the lean MAFLD group had significantly higher age （Z=3.368， P=0.001） and education level （χ²=9.647， P=0.002） and significantly lower proportion of male patients （χ²=27.664， P<0.001）， body weight （Z=-18.483， P<0.001）， BMI （Z=-23.286， P<0.001）， waist circumference （Z=-18.565， P<0.001）， and hip circumference （Z=-18.097， P<0.001）， and in terms of behavior， the non-lean MAFLD group had a significantly faster eating speed （χ²=4.549， P=0.033）. ConclusionThere is a relatively high prevalence rate of MAFLD among the physical examination population in Beijing， with a higher number of people with unhealthy lifestyles compared with the non-MAFLD population.

BACKGROUND: Inflammation plays a critical role in severe cerebral venous thrombosis (CVT) pathogenesis, but the benefits of anti-inflammatory therapies remain unclear. This study aimed to investigate the association between steroid therapy combined with anticoagulation and the prognosis of acute/subacute severe CVT patients. METHODS: A prospective cohort study enrolled patients with acute/subacute severe CVT at Xuanwu Hospital (July 2020-January 2024). Patients were allocated into steroid and non-steroid groups based on the treatment they received. Functional outcomes (modified Rankin scale [mRS]) were evaluated at admission, discharge, and 6 months after discharge. Serum high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), cerebrospinal fluid (CSF) IL-6, and intracranial pressure were measured at admission and discharge in the steroid group. Fundoscopic Frisén grades were assessed at admission and 6 months after discharge. Univariate and multivariate logistic regression were used to evaluat associations between steroid use and favorable outcomes (mRS ≤2) at the 6-month follow-up. Paired tests assessed changes in hs-CRP and other variables before and after treatment, and Spearman's correlations were used to analyze relationships between these changes and functional improvements. RESULTS: A total of 107 and 58 patients in the steroid and non-steroid groups, respectively, were included in the analysis. Compared with the non-steroid group, the steroid group had a higher likelihood of achieving an mRS score of 0-2 (93.5% vs . 82.5%, odds ratio [OR] = 2.98, P  = 0.037) at the 6-month follow-up. After adjusting for confounding factors, the result remained consistent. Pulsed steroid therapy did not increase mortality during hospitalization or follow-up, nor did it lead to severe steroid-related complications (all P  >0.05). Patients in the steroid group showed a significant reduction in serum hs-CRP, IL-6, CSF IL-6, and intracranial pressure at discharge compared to at admission, as well as a significant reduction in the fundoscopic Frisén grade at the 6-month follow-up compare to at admission (all P  <0.001). A reduction in serum inflammatory marker levels during hospitalization positively correlated with improvements in functional outcomes ( P  <0.05). CONCLUSION: Short-term steroid use may be an effective and safe adjuvant therapy for acute/subacute severe CVT when used alongside standard anticoagulant treatments, which are likely due to suppression of the inflammatory response. However, these findings require further validation in randomized controlled trials. TRAIL REGISTRATION ClinicalTrials.gov , NCT05990894.
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Anticoagulants/therapeutic use* ; C-Reactive Protein/metabolism* ; Interleukin-6/metabolism* ; Intracranial Thrombosis/drug therapy* ; Prospective Studies ; Steroids/therapeutic use* ; Venous Thrombosis/drug therapy*

Epilepsy is a chronic neurological disorder affecting ~65 million individuals worldwide. Abnormal synaptic plasticity is one of the most important pathological features of this condition. We investigated how ubiquitin-specific peptidase 47 (USP47) influences synaptic plasticity and its link to epilepsy. We found that USP47 enhanced excitatory postsynaptic transmission and increased the density of total dendritic spines and the proportion of mature dendritic spines. Furthermore, USP47 inhibited the degradation of the ubiquitinated α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) subunit glutamate receptor 1 (GluR1), which is associated with synaptic plasticity. In addition, elevated levels of USP47 were found in epileptic mice, and USP47 knockdown reduced the frequency and duration of seizure-like events and alleviated epileptic seizures. To summarize, we present a new mechanism whereby USP47 regulates excitatory postsynaptic plasticity through the inhibition of ubiquitinated GluR1 degradation. Modulating USP47 may offer a potential approach for controlling seizures and modifying disease progression in future therapeutic strategies.
Animals ; Receptors, AMPA/metabolism* ; Neuronal Plasticity/physiology* ; Seizures/physiopathology* ; Disease Models, Animal ; Mice, Inbred C57BL ; Mice ; Ubiquitin Thiolesterase/genetics* ; Male ; Excitatory Postsynaptic Potentials/physiology* ; Ubiquitination ; Dendritic Spines/metabolism* ; Hippocampus/metabolism*

ObjectiveTo identify the patients with metabolic dysfunction-associated fatty liver disease （MAFLD） among the health check-up population， and to perform stratified management of patients with the low， medium， and high risk of advanced fibrosis based on noninvasive fibrosis scores. MethodsA cross-sectional study was conducted among 3 125 individuals who underwent physical examination in Beijing Physical Examination Center from December 2017 to December 2019， and they were divided into MAFLD group with 1 068 individuals and non-MAFLD group with 2 057 individuals. According to BMI， the MAFLD group was further divided into lean MAFLD group （125 individuals with BMI<24 kg/m²） and non-lean MAFLD group （943 individuals with BMI≥24 kg/m²）. Indicators including demographic data， past history， laboratory examination， and liver ultrasound were compared between groups. Fibrosis-4 （FIB-4） score， NAFLD fibrosis score （NFS）， aspartate aminotransferase-to-platelet ratio index （APRI）， and BARD score were calculated for the patients in the MAFLD group to assess the risk of advanced fibrosis. The independent-samples t test was used for comparison of normally distributed continuous data between two groups， and the Mann-Whitney U rank sum test was used for comparison of non-normally distributed continuous data between two groups； the chi-square test or the Fisher’s exact test was used for comparison of categorical data between groups. A logistic regression analysis was used to investigate the influence of each indicator in MAFLD. ResultsCompared with the non-MAFLD group， the MAFLD group had significantly higher age （Z=-9.758， P<0.05）， proportion of male patients （χ²=137.555， P<0.05）， and levels of body weight （Z=-27.987， P<0.05）， BMI （Z=-32.714， P<0.05）， waist circumference （Z=-31.805， P<0.05）， hip circumference （Z=-26.342， P<0.05）， waist-hip ratio （Z=-28.554， P<0.05）， alanine aminotransferase （ALT） （Z=-25.820， P<0.05）， aspartate aminotransferase （AST） （Z=-16.894， P<0.05）， gamma-glutamyl transpeptidase （GGT） （Z=-25.069， P<0.05）， alkaline phosphatase （Z=-12.533， P<0.05）， triglyceride （Z=-27.559）， total cholesterol （Z=-7.833， P<0.05）， low-density lipoprotein cholesterol （LDL-C） （Z=-8.222， P<0.05）， and uric acid （UA） （Z=-20.024， P<0.05）， as well as a significantly higher proportion of patients with metabolic syndrome （MetS） （χ²=578.220， P<0.05）， significantly higher prevalence rates of hypertension （χ²=241.694， P<0.05）， type 2 diabetes （χ²=796.484， P<0.05）， and dyslipidemia （χ²=369.843， P<0.05）， and a significant reduction in high-density lipoprotein cholesterol （HDL-C） （Z=23.153， P<0.001）. The multivariate logistic regression analysis showed that male sex （odds ratio ［OR］=1.45， 95% confidence interval ［CI］： 1.203‍ ‍—‍ ‍1.737）， ALT （OR=1.05， 95%CI： 1.046‍ ‍—‍ ‍1.062）， LDL-C （OR=1.23， 95%CI： 1.102‍ ‍—‍ ‍1.373）， and comorbidity with MetS （OR=5.97， 95%CI： 4.876‍ ‍—‍ ‍7.316） were independently associated with MAFLD. Compared with the non-lean MAFLD group， the lean MAFLD group had significantly higher age （Z=3.736， P<0.05） and HDL-C （Z=2.679， P<0.05） and significant reductions in the proportion of male patients （χ²=28.970， P<0.05）， body weight （Z=-14.230， P<0.05）， BMI （Z=-18.188， P<0.05）， waist circumference （Z=-13.451， P<0.05）， hip circumference （Z=-13.317， P<0.05）， ALT （Z=-4.519， P<0.05）， AST （Z=-2.258， P<0.05）， GGT （Z=-4.592， P<0.05）， UA （Z=-4.415， P<0.05）， the proportion of patients with moderate or severe fatty liver disease or MetS （χ²=42.564， P<0.05）， and the prevalence rates of hypertension （χ²=12.057， P<0.05） and type 2 diabetes （χ²=3.174， P<0.05）. Among the patients with MAFLD， 10 patients （0.9%） had an FIB-4 score of >2.67， 4 patients （0.4%） had an NFS score of >0.676， 8 patients （0.7%） had an APRI of >1， and 551 patients （51.6%） had a BARD score of ≥2. ConclusionThere is a relatively high prevalence rate of MAFLD among the health check-up population in Beijing， but with a relatively low number of patients with a high risk of advanced fibrosis， and such patients need to be referred to specialized hospitals for liver diseases.

Objective:To explore patterns of traditional Chinese medicine (TCM) use among patients with inflammatory bowel disease (IBD) in Jiangsu Province, China from 2019 to 2023.Methods:Using data from the IBD health data platform of the National Healthcare Big Data (Eastern) Center, a retrospective cohort study was conducted. We performed descriptive analyses on hospitalised patients diagnosed with IBD between 2019 and 2023, who received TCM treatment.Results:The study included 11 095 case records from 4 760 patients, with TCM diagnoses primarily indicating diarrhoea and abdominal pain. Ulcerative colitis (UC) accounted for 4 782 hospitalizations (3 103 patients), while Crohn's disease (CD) accounted for 6 313 hospitalizations (1 657 patients). Patient demographics showed a trend towards younger age and a higher proportion of males. Treatment utilisation was highest in southern Jiangsu compared with the central and northern regions. In terms of disease burden, all treatment costs showed a downward trend. In terms of external TCM therapies, UC patients tend to prefer plasters and enemas, while CD patients are more inclined to use acupuncture. Regarding herbal medicine, licorice, white atractylodes, and white peony root are commonly used single herbs for IBD patients.Conclusions:The number of IBD patients treated with TCM in Jiangsu Province has steadily increased from 2019 to 2023. It is important to identify effective TCM treatment methods to reduce the burden of patients.

Objective:To explore the clinical efficacy and safety of endoscopic multi-band ligation (EMBL) in the management of refractory gastroesophageal reflux disease (RGERD) combined with esophageal hiatal hernia (HH).Methods:This study was a prospective, multicenter, small-sample cohort study. Patients who were diagnosed as having RGERD combined with HH at Inner Mongolia Medical University Cancer Hospital and Inner Mongolia Medical University Hospital from January 2020 to June 2022 were selected to undergo EMBL. The 24-hour esophageal pH monitoring and high-resolution manometry (HRM) related indicators, gastroesophageal reflux index (GERI), gastroesophageal reflux disease questionnaire (GERD-Q) scores, and gastroesophageal reflux disease health-related quality of life (GERD-HRQL) scores were compared before and after the operation. The patient satisfaction and complications were also investigated.Results:A total of 25 patients were included, all of whom were successfully treated with EMBL. Reflux symptoms were relieved to varied degrees in all patients. There were no serious complications during or after the operation, such as perforation, bleeding, and dysphagia. Postoperative follow-up at 6 and 12 months showed a significant decrease in DeMeester scores [18.00 (5.83, 54.75) points, 16.30 (4.38, 60.00) points] compared to preoperative baseline [105.00 (60.80, 147.70) points, Z=-3.72, P<0.001; Z=-3.82, P<0.001]. The percentage of time of pH<4 [8.80 (6.10, 11.80)%, 8.95 (5.15, 10.90)%] significantly decreased compared to the baseline [31.15 (16.75, 54.75)%, Z=-3.72, P<0.001; Z=-3.72, P<0.001], the number of long refluxes [7.90 (4.93, 11.75) times, 6.90 (4.00, 10.75) times] significantly decreased compared to the baseline [33.00 (13.00, 43.00) times, Z=-3.82, P<0.001; Z=-3.58, P<0.001], and the number of acid refluxes (14.86±8.71 times, 12.93±5.51 times) significantly decreased compared to before (30.42±17.99 times, t=5.88, P<0.001; t=4.79, P<0.001). Lower esophageal sphincter resting pressure [9.70 (5.80, 19.58) mmHg, 11.70 (5.40, 19.78) mmHg] was significantly higher compared to before [4.70 (3.25, 7.00) mmHg, Z=-2.84, P<0.001; Z=-3.10, P<0.001]. GERD-Q scores (10.00±2.01 points, 9.43±1.74 points) were significantly higher compared to before (15.34±1.51 points, t=8.90, P<0.001; t=9.87, P<0.001), GERD-HRQL scores [7.00 (5.00, 7.75) points, 6.00 (5.75, 8.25) points] significantly decreased compared to preoperative baseline [13.50 (11.00, 21.25), Z=-3.73, P<0.001; Z=-3.72, P<0.001], and GERI (2.26%±1.58%, 2.07%±1.17%) significantly decreased compared to before (5.72%±2.27%, t=8.92, P<0.001; t=9.86, P<0.001). At 6 and 12 months postoperative follow-up, patient satisfaction [68.00% (15/25), 84.00% (21/25)] significantly increased compared to before [0.00% (0/25), Z=-4.63, P<0.001; Z=-6.48, P<0.001]. Conclusion:Preliminary small-sample study has shown that EMBL is safe, reliable and effective for the treatment of RGERD with HH.

Objective To investigate the clinical and metabolic factors associated with the development and regression of metabolic dysfunction-associated fatty liver disease(MAFLD)in the physical examination population.Methods A retrospective observational study was conducted on 6 809 individuals who underwent physical examination in a physical examination institution in Beijing from December 2013 to December 2019,with a mean follow-up time of 52.1±13.5 months.According to the new diagnostic criteria for MAFLD,these individuals were divided into MAFLD group and non-MAFLD group,and the two groups were compared in terms of demographic indicators,body measurement indicators,and laboratory indicators at the first(baseline)and last physical examinations.The two-independent-samples t test was used for comparison of normally distributed continuous data between two groups,and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups;the chi-square test was used for comparison of categorical data.A Logistic regression analysis was used to investigate the impact of various observation indicators on the development and regression of MAFLD.Results In this study,there were 4 533 individuals(66.6%)in the non-MAFLD group at baseline,among whom 15.6%developed MAFLD at the last physical examination.Compared with the non-MAFLD population,the MAFLD population had significantly higher age(Z=-6.739),number of male patients(χ2=178.534),body weight(Z=-22.302),body mass index(BMI)(Z=-22.818),waist circumference(Z=-23.117),hip circumference(Z=-18.446),systolic blood pressure(SBP)(Z=-13.301),diastolic blood pressure(DBP)(Z=-13.491),fasting blood glucose(FBG)(Z=-11.787),triglyceride(TG)(Z=-16.623),low-density lipoprotein cholesterol(LDL-C)(Z=-10.256),alanine aminotransferase(ALT)(Z=-14.250),aspartate aminotransferase(AST)(Z=-7.481),and proportion of patients with metabolic syndrome(MetS)at baseline(χ2=185.283),and there were more patients with increases in body weight,waist circumference,hip circumference,TG,TC,ALT,and AST at the final physical examination(all P<0.05);these patients had a lower level of HDL-C at baseline(Z=15.416),and there were more patients with a reduction at the last physical examination(P<0.05).There were 2 276 individuals(33.4%)in the MAFLD group at baseline,among whom 23.8%showed regression of MAFLD at the last physical examination.Compared with the population without regression of MAFLD,the population with regression of MAFLD had a significantly younger age(Z=2.185),a significantly higher number of female patients(χ2=0.340),significantly lower levels of body weight(Z=-8.909),BMI(Z=-10.205),waist circumference(Z=-11.183),hip circumference(Z=-7.178),SBP(Z=-3.627),DBP(Z=-3.443),TG(Z=-5.945),ALT(Z=-9.664),and AST(Z=-5.904),and a significantly lower proportion of patients with MetS(χ2=42.082),and there were more patients with reductions in body weight,waist circumference,hip circumference,blood pressure,TG,TC,ALT,and AST at the final physical examination(all P<0.05);these patients had a higher level of HDL-C at baseline(Z=6.778),and there were more patients with an increase at the last physical examination(P<0.05).The multivariate Logistic regression analysis showed that sex and changes in body weight and HDL-C during physical examination were independently associated with the development and regression of MAFLD(all P<0.05).Conclusion There is a relatively high prevalence rate of MAFLD among the physical examination population in Beijing,with a higher proportion of male patients.There are significant metabolic disorders and liver function abnormalities,and changes in body weight and HDL-C are the most important predictive indicators for the development and regression of MAFLD.

Objective To investigate the effect of indigo on inflammatory factors and the aryl hydrocarbon receptor(AhR)/NOD-like receptor thermal protein domain associated protein 3(NLRP3)signaling pathway in lipopolysaccharide(LPS)-induced keratinocytes(HaCaT cells).Methods An LPS-induced HaCaT cell model was established,and experimental groups were set as follows:blank group,model group,indigo group,AhR agonist(2,3,7,8-tetrachlorodibenzo-p-dioxin,TCDD)group,AhR inhibitor(CH-223191)group,and indigo+AhR inhibitor group.The Cell Counting Kit-8(CCK-8)assay was used to detect the effects of different concentrations of indigo,TCDD,and CH-223191 on HaCaT cell viability after 24 hours of intervention.Quantitative real-time PCR(qPCR)was employed to measure the mRNA expression levels of interleukin-1β(IL-1β),nuclear factor kappa B(NF-κB),tumor necrosis factor-α(TNF-α),AhR,cytochrome P450 family 1 subfamily A member 1(CYP1A1),NLRP3,Caspase-1,and apoptosis-associated speck-like protein(ASC)in each group.Western Blot analysis was used to assess changes in the cellular localization of AhR protein expression.Results(1)The IC50 of indigo intervention in HaCaT cells was 118.7 μmol·L-1.Treatment with different concentrations of CH-223191 and TCDD for 24 hours had no significant effect on HaCaT cell viability.(2)Compared with the model group,the indigo group showed decreased mRNA expression levels of IL-1β,NF-κB,NLRP3,and Caspase-1(P＜0.05 or P＜0.000 1),while the mRNA expression levels of AhR and CYP1A1 were significantly increased(P＜0.05 or P＜0.000 1).(3)Compared with the blank group,the indigo group reduced cytoplasmic AhR protein expression and increased nuclear AhR protein expression(P＜0.001 or P＜0.000 1).(4)Compared with the model group,both the indigo group and the AhR agonist group significantly increased AhR mRNA expression levels(P＜0.05),while the AhR inhibitor group decreased AhR and CYP1A1 mRNA expression levels(P＜0.05)and increased IL-1β and NLRP3 mRNA expression levels(P＜0.05).(5)Compared with the AhR inhibitor group,the indigo+AhR inhibitor group showed increased mRNA expression levels of AhR and CYP1A1(P＜0.05)and decreased mRNA expression levels of NLRP3,Caspase-1,and IL-1β(P＜0.05).Conclusion Indigo reduces inflammatory factors in LPS-induced HaCaT cells and participates in inhibiting the occurrence and development of psoriasis by activating AhR to negatively regulate the NLRP3 inflammasome.

Objective To evaluate the influencing factors of aspiration in neurological critically ill patients by Meta-analysis.Methods PubMed,Embase,Web of Science,CNKI,and Wanfang Data were searched from inception to 1 October,2023,to obtain relevant studies on influencing fac-tors of aspiration in neurological critically ill patients.The literature screening,data extraction and quality evaluation were completed by two researchers.RevMan 5.4 and Stata 13.0 software were ap-plied for pooled Meta-analysisand assessed publication bias,respectively.Results A total of 8 arti-cles,including 1,315 neurocritical care patients,were included in this study.Nine influencing factors related to aspiration were extracted for Meta-analysis.The Meta-analysis results showed that the three influencing factors that caused aspiration in neurocritical care patients were stroke history(OR=5.03,95％CI,2.71 to 9.32,P＜0.000 01),National Institutes of Health Stroke Scale(NIHSS)score＞10(OR=3.35,95％CI,1.75 to 6.42,P=0.000 3),and gastric residual volume＞150mL(OR=7.13,95％CI,2.55 to 9.96,P=0.001).Conclusion This study provides a scientific basis for clinical healthcare professionals to early identify high-risk patients for aspiration,take targeted inter-vention measures,and prevent the occurrence of aspiration.

Objective To investigate the mechanisms through which Qinggan Yipi formula(QgYp)may alleviate liver fibrosis by integrating network pharmacology with experiments.Methods The active ingredients and gene targets of QgYp,associated with liver fibrosis,were sourced from several databases,including the Traditional Chinese Medicine Systems Pharmacology Database(TCMSP),various professional chemical databases,the HERB database,the GeneCards database,and the Online Mendelian Inheritance in Man(OMIM)database.Protein-protein interaction(PPI)networks were developed using the STRING database and visualized through Cytoscape software.Furthermore,GO enrichment analysis and KEGG pathway analysis were conducted with the Metascape database,alongside molecular docking studies using the CB-DOCK 2 platform.HSC-T6 cells were used as the research model,and the MTT assay along with Western blotting were applied to evaluate cell proliferation and protein expression levels,and the expression of related proteins was also detected in the animal experiment.Results A total of 22 bioactive components and 124 gene targets were identified within the formula.Enrichment analyses revealed 896 GO entries and 123 signaling pathways,notably including the IL-7,TNF,Toll-like receptor,and NF-kappa B pathways.Molecular docking indicated that the key components of the formula exhibited a strong binding affinity with proteins involved in the TLR4/NF-κB signaling pathway.Additionally,experiments confirmed that QgYp effectively inhibited the proliferation of HSC-T6 cells induced by LPS,and the expression of α-SMA,COL-1,TLR4,IκB-α,and NF-κB p65 proteins in both HSC-T6 cells and rats with liver fibrosis decreased.Conclusion QgYp can effectively inhibit the TLR4/NF-κB signaling pathway and has a suppressive effect on the fibrosis process in hepatic stellate cells,offering a theoretical basis for its clinical application in treating liver fibrosis.