Retrospective study of the incidence, risk factors, treatment outcomes of bacterial infections at uncommon sites in cirrhotic patients

BACKGROUND Bacterial infections(BI)negatively affect the natural course of cirrhosis.The most frequent BI are urinary tract infections(UTI),pneumonia,and spontaneousbacterial peritonitis(SBP).AIM To assess the relevance of bacterial infections beyond the commonly recognized types in patients with cirrhosis and to investigate their relationship with other clinical variables.METHODS We retrospectively analyzed patients with cirrhosis and BI treated between 2015 and 2018 at our tertiary care center.BIs were classified as typical and atypical,and clinical as well as laboratory parameters were compared between the two groups.RESULTS In a cohort of 488 patients with cirrhosis,we identified 225 typical BI(95 UTI,73 SBP,72 pulmonary infections)and 74 atypical BIs,predominantly cholangitis and soft tissue infections(21 each),followed by intra-abdominal BIs(n=9),cholecystitis(n=6),head/throat BIs(n=6),osteoarticular BIs(n=5),and endocarditis(n=3).We did not observe differences concerning age,sex,or etiology of cirrhosis in patients with typical vs atypical BI.Atypical BIs were more common in patients with more advanced cirrhosis,as evidenced by Model of End Stage Liver Disease(15.1±7.4 vs 12.9±5.1;P=0.005)and Child-Pugh scores(8.6±2.5 vs 8.0±2;P=0.05).CONCLUSION Atypical BIs in cirrhosis patients exhibit a distinct spectrum and are associated with more advanced stages of the disease.Hence,the work-up of cirrhosis patients with suspected BI requires detailed work-up to elucidate whether typical BI can be identified.

Phenotypic Characterization and Prevalence of Carbapenemase-Producing Acinetobacter baumanii Isolates in Four Health Facilities in Cameroon

Background and Objective: Nowadays, the clinical utility of carbapenems is threatened by the emergence of resistant bacteria, favored by its increasing use. According to the WHO, Acinetobacter baumannii: nosocomial infection agent, tops the list of priority antibiotic-resistant pathogens, considered to be the riskiest for humans. This study sought to determine the prevalence of carbapenemase-producing Acinetobacter baumannii strains in four health facilities in the Center and Littoral regions of Cameroon and the associated risk factors. Materials and Method: An analytical cross-sectional study was conducted over a six-month period from January to June 2022. All suspicious A. baumanii isolates obtained from pathological samples at the bacteriology laboratory of the different health facilities were systematically collected and re-identified. Re-identification and antimicrobial susceptibility Testing (AST) were performed using the VITEK 2 System and the Kirby-Bauer method according to the guidelines of the Clinical and Laboratory Standards Institute (CLSI). Detection and phenotypic characterization of carbapenemases was performed according to adequate standard procedures. Results: A total of 168/226 clinical isolates of Acinetobacter baumannii were confirmed after re-identification, among which 52.69% derived from male patients, 55.09% from participants aged between 10 - 39 years old, and 46.71% from pus samples. A very high resistance rates to all families of antibiotics was noted, except to colistin (10.2%). 40.12% of these isolates produced carbapenemase, represented by 62.69% of class B and 37.31% of class A. Carbapenemase production was observed only at HMR1, Centre region and at Laquintinie hospital, Littoral region with 53.33% and 50% respectively, even if there is no significant difference (P = 0.81). In addition, frequent hospitalisation was significantly associated to the production of carbapenemase among A. baumanii (Adjusted-OR = 16.53, P-value 0.0001). Conclusion: This study highlighted the emergence of carbapenemase-producing Acinetobacter baumannii which is increasingly growing. Continuous drug-resistant monitoring and preventive measures could help to prevent and curb the dissemination of A. baumanii resistance genes, especially in health settings.

Pathogenesis of hepatitis B virus infection

Infection with hepatitis B virus (HBV) leads to a wide spectrum of clinical presentations ranging from an asymptomatic carrier state to self-limited acute or fulminant hepatitis to chronic hepatitis with progression to cirrhosis and hepatocellular carcinoma. Infection with HBV is one of the most common viral diseases affecting man. Both viral factors as well as the host immune response have been implicated in the pathogenesis and clinical outcome of HBV infection. In this review, we will discuss the impact of virus-host interactions for the pathogenesis of HBV infection and liver disease. These interactions include the relevance of naturally occurring viral variants for clinical disease, the role of virus-induced apoptosis for HBV-induced liver cell injury and the impact of antiviral immune responses for outcome of infection.

Sclerosing cholangitis following severe trauma: Description of a remarkable disease entity with emphasis on possible pathophysiologic mechanisms

MM： Persistent cholestasis is a rare complication of severe trauma or infections. Little is known about the possible pathomechanisms and the clinical course.METHODS： Secondary sclerosing cholangitis was diagnosed in five patients with persistent jaundice after severe trauma （one burn injury, three accidents, one power current injury）. Medical charts were retrospectively reviewed with regard to possible trigger mechanisms for cholestasis, and the clinical course was recorded.RESULTS： Diagnosis of secondary sclerosing cholangitis was based in all patients on the primary sclerosing cholangitis （PSC）-Iike destruction of the intrahepatic bile ducts at cholangiography after exclusion of PSC. In four patients, arterial hypotension with subsequent ischemia may have caused the bile duct damage, whereas in the case of power current injury direct thermal damage was assumed to be the trigger mechanism. The course of secondary liver fibrosis was rapidly progressive and proceeded to liver cirrhosis in all four patients with a follow-up 〉2 years. Therapeutic possibilities were limited.CONCLUSION： Posttraumatic sderosing cholangitis is a rare but rapidly progressive disease, probably caused by ischemia of the intrahepatic bile ducts via the peribiliary capillary plexus due to arterial hypotension.Gastroenterologists should be aware of this disease in patients with persistent cholestasis after severe trauma.

Molecular determinants of the antitumor effects of trichostatin A in pancreatic cancer cells

AIM:To gain molecular insights into the action of the histone deacetylase inhibitor(HDACI) trichostatin-A(TSA) in pancreatic cancer(PC) cells.METHODS:Three PC cell lines,BxPC-3,AsPC-1 and CAPAN-1,were treated with various concentrations of TSA for def ined periods of time.DNA synthesis was assessed by measuring the incorporation of 5-bromo-2'deoxyuridine.Gene expression at the level of mRNA was quantif ied by real-time polymerase chain reaction.Expression and phosphorylation of proteins was monitored by immunoblotting,applying an infrared imaging technology.To study the role of p38 MAP kinase,the specif ic enzyme inhibitor SB202190 and an inactive control substance,SB202474,were employed.RESULTS:TSA most eff iciently inhibited BrdU incorporation in BxPC-3 cells,while CAPAN-1 cells displayed the lowest and AsPC-1 cells an intermediate sensitivity.The biological response of the cell lines correlated with the increase of histone H3 acetylation after TSA application.In BxPC-3 cells(which are wild-type for KRAS),TSA strongly inhibited phosphorylation of ERK 1/2 and AKT.In contrast,activities of ERK and AKT in AsPC-1 and CAPAN-1 cells(both expressing oncogenic KRAS) were not or were only modestly affected by TSA treatment.In all three cell lines,but most pronounced in BxPC-3 cells,TSA exposure induced an activation of the MAP kinase p38.Inhibition of p38 by SB202190 slightly but signif icantly diminished the antiproliferative effect of TSA in BxPC-3 cells.Interestingly,only BxPC-3 cells responded to TSA treatment by a signif icant increase of the mRNA levels of bax,a pro-apoptotic member of the BCL gene family.Finally,in BxPC-3 and AsPC-1 cells,but not in the cell line CAPAN-1,signif icantly higher levels of the cell cycle inhibitor protein p21Waf1 were observed after TSA application.CONCLUSION:The biological effect of TSA in PC cells correlates with the increase of acetyl-H3,p21Waf1,phospho-p38 and bax levels,and the decrease of phosphoERK 1/2 and phospho-AKT.

Interaction of hepatitis C virus envelope glycoprotein E2 with the large extracellular loop of tupaia CD81

AIM: To further analyze the interaction of tupaia CD81 with hepatitis C virus (HCV) envelope protein E2. METHODS: A tupaia CD81 large extracellular loop (CD81 LEL), which binds to HCV E2 protein, was cloned and expressed as a GST-fusion protein, and interaction of HCV E2 protein with a tupaia CD81 LEL was evaluated by enzyme-linked immunosorbent assay (EIA). RESULTS: Although tupaia and human CD81 LEL differed in 6 amino acid changes, tupaia CD81 LEL was strongly recognized by anti-CD81 antibodies against human CD81 LEL conformation-dependent epitopes. Investigating LEL CD81-E2 interactions by EIA, we demonstrated that binding of tupaia CD81 LEL GST fusion protein to recombinant HCV E2 protein was markedly reduced compared to binding of human CD81 LEL GST fusion protein to recombinant HCV E2 protein. CONCLUSION: These data suggest that the structural differences in-between the tupaia and human CD81 may alter the interaction of the large extracellular loop with HCV envelope glycoprotein E2. These findings may be important for the understanding of the mechanisms of binding and entry of HCV to PTHs.

Expression of tissue factor in pancreatic adenocarcinoma is associated with activation of coagulation

AIM： To study expression of tissue factor （TF） in pancreatic cancer and its role in the development of thromboembolism.METHODS： TF expression was studied in eight human pancreatic carcinoma cell lines by Northern blot and indirect immunofluorescence. Expression of alternatively spliced TF （asTF） was assessed by RT-PCR. In addition, TF expression was determined by immunofluorescence in pancreatic tissues of 19 patients with pancreatic adenocarcinoma （PCa）, 9 patients with chronic pancreatitis （CP） and 20 normal controls. Plasma samples （30 PCa-patients, 13 CP-patients and 20 controls） were investigated for soluble TF levels and coagulation activation markers [thrombin-antithrombin Ⅲ complex （TAT）, prothrombin fragment 1 ＋ 2 （F1 ＋ 2）]. RESULTS： All pancreatic carcinoma cell lines expressed TF （8/8） and most of them expressed asTF （6/8）. TF expression at the protein level did not correlate with the differentiation of the carcinoma cell line. All but two pancreatic cancer tissue samples stained positive for TF （17/19）. In all samples of CP weak staining was restricted to pancreatic duct cells, whereas only a few subendothelial cells were positive in 9/20 of normal controls. TF and TAT levels in PCa patients were significantly elevated compared to controls whereas elevated F1 ＋ 2 levels did not reach statistical significance compared to controls. In CP patients TAT and F1 ＋ 2 levels proved to be significantly elevated compared to controls, although TAT elevation was less pronounced than in PCa patients. CONCLUSION： We conclude that in addition to the upregulated expression of TF on the cell membrane, soluble TF might contribute to activation of the coagulation system in pancreatic cancer.

Enhanced expression of interleukin-18 in serum and pancreas of patients with chronic pancreatitis

AIM： To investigate interleukin-18 （IL-18） in patients with chronic panreatitis （CP）. METHODS： We studied 29 patients with CP and 30 healthy controls. Peripheral blood mononuclear cells （PBMC） were isolated and incubated with 50 mmol/L ethanol, lipopolysaccharide （LPS） （doses 25 g/L, 250 g/L, 2500 g/L） and both agents for 24 h. Levels of IL-18 in the supernatants, and levels of IL-18, IL-12, interferon （IFN）-T and soluble CD14 in the serum were analysed by EI_ISA technique. Expression of IL-18 in PBMC was investigated by reverse-transcription （RT）-PCR. IL-18 protein levels in CP tissue and in normal pancreas were studied by ELISA technique. IL-18 levels in PBMC and pancreatic tissue were determined by Westernblot. Immunohistochemistry for pancreatic IL-18 expression was performed.RESULTS： In patients, IL-18 serum levels were significantly enhanced by 76% （mean： 289.9 ± 167.7 ng/L） compared with controls （mean： 165.2 ± 43.6 ng/L; P 〈 0.0005）. IL-12 levels were enhanced by 25% in patients （18.3 ± 7.3 ng/L） compared with controls （14.7 ± 6.8 ng/L, P = 0.0576） although not reaching the statistical significance. IFN-γ, and soluble CD14 levels were not increased. In vitro, LPS stimulated significantly and dosedependently IL-18 secretion from PBMC. Incubation with ethanol reduced LPS-stimulated IL-18 secretion by about 50%. The mRNA expression of IL-18 in PBMC and the response of PBMC to ethanol and LPS was similar in CP patients and controls. In PBMC, no significant differences in IL-18 protein levels were detected between patients and controls. IL-18 protein levels were increased in CP tissues compared to normal pancreatic tissues. IL-18 was expressed by pancreatic acinar cells and by infiltrating inflammatory cells within the pancreas. CONCLUSION： IL-18 originates from the chronically inflammed pancreas and appears to be involved in the fibrotic destruction of the organ.

Mucin and phospholipids determine viscosity of gallbladder bile in patients with gallstones

AIM: An increased viscosity of gallbladder bile has been considered an important factor in the pathogenesis of gallstone disease. Besides lipids and proteins, mucin has been suggested to affect the viscosity of bile. To further clarify these issues we compared mucin, protein and the lipid componEnts of hepatic and gallbladder bile and its viscosity in patients with gallstones. METHODS: Viscosity of bile (mPa.s) was measured using rotation viscosimetry in regard to the non Newtonian property of bile at low shear rates. RESULTS: Biliary viscosity was markedly higher in gallbladder bile of patients with cholesterol (5.00 +/- 0.60 mPa.s, mean +/- SEM, r= 28) and mixed stones (3.50 +/- 0.68 mPa.s; r= 8) compared to hepatic bile (0.92 +/- 0.06 mPa.s, r= 6). A positive correlation between mucin and viscosity was found in gallbladder biles (r = 0.65; P 【 0.001) but not in hepatic biles. The addition of physiologic and supraphysiologic amounts of mucin to gallbladder bile resulted in a dose dependent non linear increase of its viscosity. A positive correlation was determined between phospholipid concentration and viscosity (r = 0.34, P 【 0.005) in gallbladder biles. However, no correlation was found between total protein or the other lipid concentrations and viscosity in both gallbladder and hepatic biles. CONCLUSION: The viscosity of gallbladder bile is markedly higher than that of hepatic bile in patients with gallstones. The concentration of mucin is the major determinant of biliary viscosity and may contribute by this mechanism to the role of mucin in the pathogenesis of gallstones.

Different characteristics of chronic dibutyltin dichloride-induced pancreatitis and cholangitis in mouse and rat

Background:Current animal models of chronic pancreatitis(CP)often provide only limited pathophysio-logical insights since they incompletely reflect the human disease.CP induced by injection of dibutyltin dichloride(DBTC-pancreatitis)shares with human CP the important feature of extended fibrosis and would be an even more attractive model if it could be transferred from rats to mice,as recently sug-gested in the context of combined ethanol and DBTC application.This study aimed to evaluate the effects of DBTC in pancreas and liver of C57BL/6 mice,a strain commonly used to engineer genetic mouse mod-els.Methods:C57BL/6 mice and Lewis rats were exposed to variable doses of DBTC.After an investigation period of up to 4 weeks,laboratory findings and histopathological changes of pancreas and liver were evaluated.Results:Chronic DBTC-pancreatitis in rats was characterized by acinar cell damage,ductal changes,fi-brosis,and inflammatory cell infiltrates.Mice treated with DBTC at 6–8 mg/kg body weight,the standard doses in rats,showed transient increases of lipase activities but no morphological signs of chronic DBTC-pancreatitis 4 weeks after injection of the drug.Increased doses of 10–12 mg/kg DBTC were intolerable due to their high toxicity.In contrast,mice and rats presented with a similar histopathology of the liver that can be characterized as a chronic-proliferative DBTC-cholangitis with predominating damage and proliferation of the small bile ducts as well as secondary portal inflammatory cell infiltrates and a begin-ning portal fibrosis.Conclusions:The DBTC-model cannot be transferred from rats to C57BL/6 mice with respect to chronic DBTC-pancreatitis,but might be of interest to study DBTC-cholangitis in both species.

Analysis of the nitric oxide-cyclic guanosine monophosphate pathway in experimental liver cirrhosis suggests phosphodiesterase-5 as potential target to treat portal hypertension

AIM To investigate the potential effect of inhibitors of phosphodiesterase-5(PDE-5) for therapy of portal hypertension in liver cirrhosis.METHODS In the rat model of thioacetamide-induced liver fibrosis/cirrhosis the nitric oxide-cyclic guanosine monophosphate(NO-cGMP) pathway was investigated. Expression and localization of PDE-5, the enzyme that converts vasodilating cGMP into inactive 5'-GMP, was in the focus of the study. Hepatic gene expression of key components of the NO-cGMP pathway was determined by qRT-PCR: Endothelial NO synthase(eNOS), inducible NO synthase(iNOS), soluble guanylate cyclase subunits α1 and β1(sGCa1, sGCb1), and PDE-5. Hepatic PDE-5 protein expression and localization were detected by immunohistochemistry. Serum cGMP concentrations were measured using ELISA. Acute effects of the PDE-5 inhibitor Sildenafil(0.1 mg/kg or 1.0 mg/kg) on portal and systemic hemodynamics were investigated using pressure transducers.RESULTS Hepatic gene expression of eNOS(2.2-fold; P = 0.003), sGCa1(1.7-fold; P = 0.003), sGCb1(3.0-fold; P = 0.003), and PDE-5(11-fold; P = 0.003) was increased in cirrhotic livers compared to healthy livers. Overexpression of PDE-5(7.7-fold; P = 0.006) was less pronounced in fibrotic livers. iNOS expression was only detected in fibrotic and cirrhotic livers. In healthy liver, PDE-5 protein was localized primarily in zone 3 hepatocytes and to a lesser extent in perisinusoidal cells. This zonation was disturbed in cirrhosis: PDE-5 protein expression in perisinusoidal cells was induced approximately 8-fold. In addition, PDE-5-expressing cells were also found in fibrous septa. Serum cGMP concentrations were reduced in rats with cirrhotic livers by approximately 40%. Inhibition of PDE-5 by Sildenafil caused a significant increase in serum cGMP concentrations [+ 64% in healthy rats(P = 0.024), + 85% in cirrhotic rats(P = 0.018)]. Concomitantly, the portal venous pressure was reduced by 19% in rats with liver cirrhosis. CONCLUSION Overexpression and abrogated zonation of PDE-5 likely contribute to the pathogenesis of cirrhotic portal hypertension. PDE-5 inhibition may therefore be a reasonable therapeutic approach for portal hypertension.

NOD2-and disease-specific gene expression profiles of peripheral blood mononuclear cells from Crohn's disease patients

AIM To investigate disease-specific gene expression profiles of peripheral blood mononuclear cells(PBMCs) from Crohn's disease(CD) patients in clinical remission.METHODS Patients with CD in clinical remission or with very low disease activity according to the Crohn's disease activity index were genotyped regarding nucleotidebinding oligomerization domain 2(NOD2),and PBMCs from wild-type(WT)-NOD2 patients,patients with homozygous or heterozygous NOD2 mutations and healthy donors were isolated for further analysis.The cells were cultured with vitamin D,peptidoglycan(PGN) and lipopolysaccharide(LPS) for defined periods of time before RNA was isolated and subjected to microarray analysis using Clariom S assays and quantitative realtime PCR.NOD2-and disease-specific gene expression profiles were evaluated with repeated measure ANOVA by a general linear model.RESULTS Employing microarray assays,a total of 267 genes were identified that were significantly up-or downregulated in PBMCs of WT-NOD2 patients,compared to healthy donors after challenge with vitamin D and/or a combination of LPS and PGN(P < 0.05;threshold:≥ 2-fold change).For further analysis by real-time PCR,genes with known impact on inflammation and immunity were selected that fulfilled predefined expression criteria.In a larger cohort of patients and controls,a disease-associated expression pattern,with higher transcript levels in vitamin D-treated PBMCs from patients,was observed for three of these genes,CLEC5 A(P < 0.030),lysozyme(LYZ;P < 0.047) and TREM1(P < 0.023).Six genes were found to be expressed in a NOD2-dependent manner(CD101,P < 0.002;CLEC5 A,P < 0.020;CXCL5,P < 0.009;IL-24,P < 0.044;ITGB2,P < 0.041;LYZ,P < 0.042).Interestingly,the highest transcript levels were observed in patients with heterozygous NOD2 mutations.CONCLUSION Our data identify CLEC5 A and LYZ as CD-and NOD2-associated genes of PBMCs and encourage further studies on their pathomechanistic roles.

High rate of complete histopathological response in hepatocellular carcinoma patients after combined transarterial chemoembolization and stereotactic body radiation therapy

BACKGROUND Liver transplantation(LT)presents a curative treatment option in patients with early stage hepatocellular carcinoma(HCC)who are not eligible for resection or ablation therapy.Due to a risk of up 30%for waitlist drop-out upon tumor progression,bridging therapies are used to halt tumor growth.Transarterial chemoembolization(TACE)and less commonly stereotactic body radiation therapy(SBRT)or a combination of TACE and SBRT,are used as bridging therapies in LT.However,it remains unclear if one of those treatment options is superior.The analysis of explant livers after transplantation provides the unique opportunity to investigate treatment response by histopathology.AIM To analyze histopathological response to a combination of TACE and SBRT in HCC in comparison to TACE or SBRT alone.METHODS In this multicenter retrospective study,27 patients who received liver transplantation for HCC were analyzed.Patients received either TACE or SBRT alone,or a combination of TACE and SBRT as bridging therapy to liver transplantation.Liver explants of all patients who received at least one TACE and/or SBRT were analyzed for the presence of residual vital tumor tissue by histopathology to assess differences in treatment response to bridging therapies.Statistical analysis was performed using Fisher-Freeman-Halton exact test,Kruskal-Wallis and Mann-Whitney-U tests.RESULTS Fourteen patients received TACE only,four patients SBRT only,and nine patients a combination therapy of TACE and SBRT.There were no significant differences between groups regarding age,sex,etiology of underlying liver disease or number and size of tumor lesions.Strikingly,analysis of liver explants revealed that almost all patients in the TACE and SBRT combination group(8/9,89%)showed no residual vital tumor tissue by histopathology,whereas TACE or SBRT alone resulted in significantly lower rates of complete histopathological response(0/14,0%and 1/4,25%,respectively,P value<0.001).CONCLUSION Our data suggests that a combination of TACE and SBRT increases the rate of complete histopathological response compared to TACE or SBRT alone in bridging to liver transplantation.

Molecular Therapy and Prevention of Liver Diseases

Molecular analyses have become an integral part of biomedical research as well as clinical medicine. The definition of the genetic basis of many human diseases has led to a better understanding of their pathogenesis and has in addition offered new perspectives for their diagnosis, therapy and prevention. Genetically, human diseases can be classified as hereditary monogenic, acquired monogenic and polygenic diseases. Based on this classification, gene therapy is based on six concepts: (1) gene repair, (2) gene substitution, (3) cell therapy, (4) block of gene expression or function, (5) DNA vaccination and (6) gene augmentation. While major advances have been made in all areas of gene therapy during the last years, various delivery, targeting and safety issues need to be addressed before these strategies will enter clinical practice. Nevertheless, gene therapy will eventually become part of the management of patients with various liver diseases, complementing or replacing existing therapeutic and preventive strategies.

Uncoupling protein 2 deficiency reduces proliferative capacity of murine pancreatic stellate cells

BACKGROUND： Uncoupling protein 2 （UCP2） has been suggested to inhibit mitochondrial production of reactive oxygen species （ROS） by decreasing the mitochondrial membrane potential. Experimental acute pancreatitis is associated with increased UCP2 expression, whereas UCP2 deficiency retards regeneration of aged mice from acute pancreatitis. Here, we have addressed biological and molecular functions of UCP2 in pancreatic stellate cells （PSCs）, which are involved in pancreatic wound repair and fibrogenesis. METHODS： PSCs were isolated from 12 months old （aged） UCP2^-/- mice and animals of the wild-type （WT） strain C57BL/6. Proliferation and cell death were assessed by em- ploying trypan blue staining and a 5-bromo-2＇-deoxyuridine incorporation assay. Intracellular fat droplets were visualized by oil red O staining. Levels of mRNA were determined by RT-PCR, while protein expression was analyzed by immunoblotting and immunofluorescence analysis. Intracellular ROS levels were measured with 2＇,7＇-dichlorofluorescin diacetate. Expression of senescence-associated β-galactosidase （SA β-Gal） was used as a surrogate marker of cellular senescence. RESULTS： PSCs derived from UCP2^-/- mice proliferated at a lower rate than cells from WT mice. In agreement with this observation, the UCP2 inhibitor genipin displayed dose- dependent inhibitory effects on WT PSC growth. Interestingly, ROS levels in PSCs did not differ between the two strains, and PSCs derived from UCP2^-/- mice did not senesce faster than those from corresponding WT cells. PSCs from UCP2^-/- mice and WT animals were also indistinguishable with respect to the activation-dependent loss of intracellular fat droplets, expression of the activation marker α-smooth muscle actin, type I collagen and the autocrine/paracrine mediators interleukin-6 and transforming growth factor-I~ 1. CONCLUSIONS： A reduced proliferative capacity of PSC from aged UCP2^-/- mice may contribute to the retarded regeneration after acute pancreatitis. Apart from their slower growth, PSC of UCP2^-/- mice displayed no functional abnormalities. The antifibrotic potential of UCP2 inhibitors deserves further attention.

Effect of eicosapentaenoic acid on regional arterial stiffness:Assessment by tissue Doppler imaging

AIM: To evaluate the effects of eicosapentaenoic acid (EPA) on regional arterial stiffness assessed by strain rate using tissue Doppler imaging. METHODS: Nineteen eligible patients were prospectively studied (mean age 62 ± 8 years, 68% men). Subjects with large vessel complications and/or diabetes mellitus were excluded. The strain rate of the ascending aorta was measured by tissue Doppler imaging as an index of regional arterial stiffness, and brachial-ankle pulse wave velocity (baPWV) was measured as an index of degree of systemic arteriosclerosis. These indices were compared before and after administration of EPA at 1800 mg/d for one year. RESULTS: The plasma concentration of EPA increased significantly after EPA administration (3.0% ± 1.1% to 8.5% ± 2.9%, P < 0.001). There were no significant changes in baPWV (1765 ± 335 cm/s to 1745 ± 374 cm/s), low-density lipoprotein cholesterol levels (114 ± 29 mg/dL to 108 ± 28 mg/dL), or systolic blood pressure (131 ± 16 mmHg to 130 ± 13 mmHg) before and after EPA administration. In contrast, the strain rate was significantly increased by administration of EPA (19.2 ± 5.6 s-1, 23.0 ± 6.6 s-1, P < 0.05). CONCLUSION: One year of administration of EPA resulted in an improvement in regional arterial stiffness which was independent of blood pressure or serum cholesterol levels.

Baseline neutrophil-lymphocyte ratio and platelet-lymphocyte ratio appear predictive of immune treatment related toxicity in hepatocellular carcinoma

BACKGROUND A well-recognized class effect of immune checkpoint inhibitors(ICI)is immune-related adverse events(IrAEs)ranging from low grade toxicities to life-threatening end organ damage requiring permanent discontinuation of ICI.Deaths are reported in<5%of patients treated with ICI.There are,however,no reliable markers to predict the onset and severity of IrAEs.We tested the association between neutrophil-lymphocyte ratio(NLR)and platelet-lymphocyte ratio(PLR)at baseline with development of clinically significant IrAEs(grade≥2)in hepatocellular carcinoma(HCC)patients treated with ICI.AIM To test the association between NLR and PLR at baseline with development of clinically significant IrAEs(grade≥2)in HCC patients treated with ICI.METHODS Data was extracted from an international database from a consortium of 11 tertiary-care referral centers.NLR=absolute neutrophil count/absolute lymphocyte count(ALC)and PLR=platelet count/ALC.Cutoff of 5 was used for NLR and 300 for PLR based on literature.We also tested the association between RESULTS Data was collected from 361 patients treated between 2016-2020 across the United States(67%),Asia(14%)and Europe(19%).Most patients received Nivolumab(n=255,71%).One hundred sixty-seven(46%)patients developed at least one IrAE,highest grade 1 in 80(48%),grade≥2 in 87(52%)patients.In a univariable regression model PLR>300 was significantly associated with a lower incidence of grade≥2 IrAEs(OR=0.40;P=0.044).Similarly,a trend was observed between NLR>5 and lower incidence of grade≥2 IrAEs(OR=0.58;P=0.097).Multivariate analyses confirmed PLR>300 as an independent predictive marker of grade≥2 IrAEs(OR=0.26;P=0.011),in addition to treatment with programmed cell death ligand 1(PD-1)/cytotoxic T lymphocyte-associated protein-4(OR=2.57;P=0.037)and PD-1/tyrosine kinase inhibitor(OR=3.39;P=0.01)combinations.Antibiotic use was not associated with IrAE incidence(OR=1.02;P=0.954).Patients treated with steroids had a>2-fold higher incidence of grade≥2 IrAEs(OR=2.74;P<0.001),although 74%were prescribed steroids for the treatment of IrAEs.CONCLUSION Given that high baseline NLR and PLR are associated with a decreased incidence of IrAEs,lower baseline NLR and PLR may be predictive biomarkers for the appearance of IrAEs in HCC treated with ICI.This finding is in keeping with several studies in solid tumors that have shown that baseline NLR and PLR appear predictive of IrAEs.

Trypsin in pancreatitis:The culprit,a mediator,or epiphenomenon?

Pancreatitis is a common,life-threatening inflammatory disease of the exocrine pancreas.Its pathogenesis remains obscure,and no specific or effective treatment is available.Gallstones and alcohol excess are major etiologies of pancreatitis;in a small portion of patients the disease is hereditary.Pancreatitis is believed to be initiated by injured acinar cells(the main exocrine pancreas cell type),leading to parenchymal necrosis and local and systemic inflammation.The primary function of these cells is to produce,store,and secrete a variety of enzymes that break down all categories of nutrients.Most digestive enzymes,including all proteases,are secreted by acinar cells as inactive proforms(zymogens)and in physiological conditions are only activated when reaching the intestine.The generation of trypsin from inactive trypsinogen in the intestine plays a critical role in physiological activation of other zymogens.It was proposed that pancreatitis results from proteolytic autodigestion of the gland,mediated by premature/inappropriate trypsinogen activation within acinar cells.The intra-acinar trypsinogen activation is observed in experimental models of acute and chronic pancreatitis,and in human disease.On the basis of these observations,it has been considered the central pathogenic mechanism of pancreatitis-a concept with a century-old history.This review summarizes the data on trypsinogen activation in experimental and genetic rodent models of pancreatitis,particularly the more recent genetically engineered mouse models that mimic mutations associated with hereditary pancreatitis;analyzes the mechanisms mediating trypsinogen activation and protecting the pancreas against its’damaging effects;discusses the gaps in our knowledge,potential therapeutic approaches,and directions for future research.We conclude that trypsin is not the culprit in the disease pathogenesis but,at most,a mediator of some pancreatitis responses.Therefore,the search for effective therapies should focus on approaches to prevent or normalize other intra-acinar pathologic processes,such as defective autophagy leading to parenchymal cell death and unrelenting inflammation.

First-line endoscopic treatment with over-the-scope clips significantly improves the primary failure and rebleeding rates in high-risk gastrointestinal bleeding: A single-center experience with 100 cases

AIM To evaluate rebleeding, primary failure(PF) and mortality of patients in whom over-the-scope clips(OTSCs) were used as first-line and second-line endoscopic treatment(FLET, SLET) of upper and lower gastrointestinal bleeding(UGIB, LGIB).METHODS A retrospective analysis of a prospectively collected database identified all patients with UGIB and LGIB in a tertiary endoscopic referral center of the University of Freiburg, Germany, from 04-2012 to 05-2016(n= 93) who underwent FLET and SLET with OTSCs. The complete Rockall risk scores were calculated from patients with UGIB. The scores were categorized as < or ≥ 7 and were compared with the original Rockall data. Differences between FLET and SLET were calculated. Univariate and multivariate analysis were performed to evaluate the factors that influenced rebleeding after OTSC placement.RESULTS Primary hemostasis and clinical success of bleeding lesions(without rebleeding) was achieved in 88/100(88%) and 78/100(78%), respectively. PF was significantly lower when OTSCs were applied as FLET compared to SLET(4.9% vs 23%, P = 0.008). In multivariate analysis, patients who had OTSC placement as SLET had a significantly higher rebleeding risk compared to those who had FLET(OR 5.3; P = 0.008). Patients with Rockall risk scores ≥ 7 had a significantly higher in-hospital mortality compared to those with scores < 7(35% vs 10%, P = 0.034). No significant differences were observed in patients with scores < or ≥ 7 in rebleeding and rebleeding-associated mortality.CONCLUSION Our data show for the first time that FLET with OTSC might be the best predictor to successfully prevent rebleeding of gastrointestinal bleeding compared to SLET. The type of treatment determines the success of primary hemostasis or primary failure.

CD4+ T cell responses in hepatitis C virus infection

Hepatitis C virus (HCV) infection is a major cause of liver damage, with virus-induced end-stage disease such as liver cirrhosis and hepatocellular carcinoma resulting in a high rate of morbidity and mortality worldwide. Evidence that CD4+ T cell responses to HCV play an important role in the outcome of acute infection has been shown in several studies. However, the mechanisms behind viral persistence and the failure of CD4+ T cell responses to contain virus are poorly understood. During chronic HCV infection, HCV-specific CD4+ T cell responses are rela- tively weak or absent whereas in resolved infection these responses are vigorous and multispecific. Persons with a T-helper type I profile, which promotes cellular effec- tor mechanisms are thought to be more likely to experi- ence viral clearance, but the overall role of these cells in the immunopathogenesis of chronic liver disease is not known. To define this, much more data is required on the function and specificity of virus-specific CD4+ T cells, especially in the early phases of acute disease and in the liver during chronic infection. The role and possible mechanisms of action of CD4+ T cell responses in deter- mining the outcome of acute and chronic HCV infection will be discussed in this review.