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1.
BMJ Open Gastroenterol ; 11(1)2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38302475

ABSTRACT

OBJECTIVE: Coeliac disease (CD) diagnosis generally depends on histological examination of duodenal biopsies. We present the first study analysing the concordance in examination of duodenal biopsies using digitised whole-slide images (WSIs). We further investigate whether the inclusion of immunoglobulin A tissue transglutaminase (IgA tTG) and haemoglobin (Hb) data improves the interobserver agreement of diagnosis. DESIGN: We undertook a large study of the concordance in histological examination of duodenal biopsies using digitised WSIs in an entirely virtual reporting setting. Our study was organised in two phases: in phase 1, 13 pathologists independently classified 100 duodenal biopsies (40 normal; 40 CD; 20 indeterminate enteropathy) in the absence of any clinical or laboratory data. In phase 2, the same pathologists examined the (re-anonymised) WSIs with the inclusion of IgA tTG and Hb data. RESULTS: We found the mean probability of two observers agreeing in the absence of additional data to be 0.73 (±0.08) with a corresponding Cohen's kappa of 0.59 (±0.11). We further showed that the inclusion of additional data increased the concordance to 0.80 (±0.06) with a Cohen's kappa coefficient of 0.67 (±0.09). CONCLUSION: We showed that the addition of serological data significantly improves the quality of CD diagnosis. However, the limited interobserver agreement in CD diagnosis using digitised WSIs, even after the inclusion of IgA tTG and Hb data, indicates the importance of interpreting duodenal biopsy in the appropriate clinical context. It further highlights the unmet need for an objective means of reproducible duodenal biopsy diagnosis, such as the automated analysis of WSIs using artificial intelligence.


Subject(s)
Celiac Disease , Humans , Celiac Disease/diagnosis , Transglutaminases , Artificial Intelligence , Observer Variation , Immunoglobulin A
2.
Genet Med ; 21(10): 2390-2400, 2019 10.
Article in English | MEDLINE | ID: mdl-30918358

ABSTRACT

PURPOSE: There are no internationally agreed upon clinical guidelines as to which women with gynecological cancer would benefit from Lynch syndrome screening or how best to manage the risk of gynecological cancer in women with Lynch syndrome. The Manchester International Consensus Group was convened in April 2017 to address this unmet need. The aim of the Group was to develop clear and comprehensive clinical guidance regarding the management of the gynecological sequelae of Lynch syndrome based on existing evidence and expert opinion from medical professionals and patients. METHODS: Stakeholders from Europe and North America worked together over a two-day workshop to achieve consensus on best practice. RESULTS: Guidance was developed in four key areas: (1) whether women with gynecological cancer should be screened for Lynch syndrome and (2) how this should be done, (3) whether there was a role for gynecological surveillance in women at risk of Lynch syndrome, and (4) what preventive measures should be recommended for women with Lynch syndrome to reduce their risk of gynecological cancer. CONCLUSION: This document provides comprehensive clinical guidance that can be referenced by both patients and clinicians so that women with Lynch syndrome can expect and receive appropriate standards of care.


Subject(s)
Colorectal Neoplasms, Hereditary Nonpolyposis/therapy , Endometrial Neoplasms/therapy , Genital Neoplasms, Female/therapy , Colorectal Neoplasms, Hereditary Nonpolyposis/epidemiology , Consensus , Early Detection of Cancer , Endometrial Neoplasms/epidemiology , Europe , Female , Genital Neoplasms, Female/epidemiology , Humans , Mass Screening , North America , Ovarian Neoplasms/epidemiology , Ovarian Neoplasms/therapy
3.
AIDS ; 30(9): 1375-83, 2016 06 01.
Article in English | MEDLINE | ID: mdl-26836788

ABSTRACT

OBJECTIVE: The study sought to establish the feasibility and acceptability of anal screening among men MSM. DESIGN: Prospective cohort study. SETTING: Sexual health clinics in tertiary care. PATIENTS: Known HIV-positive and negative MSM who have anoreceptive intercourse. INTERVENTION: Anal screening with human papilloma virus (HPV) testing, liquid-based cytology and high-resolution anoscopy with biopsy of anoscopic abnormalities. Participants completed questionnaires at baseline and at 6 months. RESULTS: Anal HPV was highly prevalent in MSM (HIV-positive, 88% and HIV-negative, 78%). Despite the high prevalence of cytological abnormality in both HIV-positive (46.2%) and negative (35.0%) MSM, almost half of anal intraepithelial neoplasia (AIN) of all grades were associated with negative cytology. Anoscopically directed biopsies detected AIN3 or worse (AIN3+) in 14 of 203 (6.9%) of HIV-positive MSM and three of 81 (3.7%) HIV-negative MSM. The corresponding prevalence of AIN2+ was 26.6 and 20.9%, respectively. One case of AIN3 was detected at the second visit. Screening was considered to be highly acceptable by participants. CONCLUSION: The high prevalence of high-risk-HPV and frequency of false negative cytology in this study suggest that high-resolution anoscopy would have most clinical utility, as a primary screening tool for anal cancer in a high-risk group. The prevalence of AIN3+ in HIV-positive MSM lends support for a policy of screening this group, but the high prevalence of lower grade lesions which do not warrant immediate treatment and the limitations of treating high-grade lesions requires careful consideration in terms of a screening policy.


Subject(s)
Anus Neoplasms/diagnosis , Early Detection of Cancer/statistics & numerical data , Papillomavirus Infections/diagnosis , Patient Acceptance of Health Care , Adult , Aged , Biopsy , Cytological Techniques , Endoscopy , HIV Infections/complications , Homosexuality, Male , Humans , Male , Middle Aged , Pathology , Prospective Studies , Surveys and Questionnaires
4.
Cancer Res ; 74(12): 3344-56, 2014 Jun 15.
Article in English | MEDLINE | ID: mdl-24713432

ABSTRACT

The c-Jun N-terminal protein kinase (JNK) and its two direct activators, namely the mitogen-activated protein kinase (MAPK) kinase 4 (MKK4) and MKK7, constitute a signaling node frequently mutated in human pancreatic ductal adenocarcinoma (PDAC). Here we demonstrate the cooperative interaction of endogenous expression of Kras(G12D) with loss-of-function mutations in mkk4 or both, mkk4 and mkk7 genes in the pancreas. More specifically, impaired JNK signaling in a subpopulation of Pdx1-expressing cells dramatically accelerated the appearance of Kras(G12D)-induced acinar-to-ductal metaplasia and pancreatic intraepithelial neoplasias, which rapidly progressed to invasive PDAC within 10 weeks of age. Furthermore, inactivation of mkk4/mkk7 compromised acinar regeneration following acute inflammatory stress by locking damaged exocrine cells in a permanently de-differentiated state. Therefore, we propose that JNK signaling exerts its tumor suppressive function in the pancreas by antagonizing the metaplastic conversion of acinar cells toward a ductal fate capable of responding to oncogenic stimulation.


Subject(s)
Carcinoma, Pancreatic Ductal/metabolism , MAP Kinase Kinase 4/genetics , MAP Kinase Kinase 7/genetics , Pancreatic Neoplasms/metabolism , Proto-Oncogene Proteins p21(ras)/genetics , Acinar Cells/enzymology , Animals , Carcinogenesis/metabolism , Carcinoma, Pancreatic Ductal/genetics , Cell Dedifferentiation , MAP Kinase Kinase 4/metabolism , MAP Kinase Kinase 7/metabolism , MAP Kinase Signaling System , Mice , Mice, Transgenic , Mutation, Missense , Pancreas/enzymology , Pancreas/pathology , Pancreas/physiopathology , Pancreatic Neoplasms/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Regeneration
5.
JOP ; 14(6): 610-7, 2013 Nov 10.
Article in English | MEDLINE | ID: mdl-24216546

ABSTRACT

CONTEXT: Microvascular thrombosis is a critical event in severe acute pancreatitis. Human recombinant activated protein C (Xigris®, Eli Lilly, Indianapolis, IN, USA) modulates the interplay between pro-inflammatory and pro-coagulant pathways and maintains microvascular patency. However, the anticoagulant properties of Xigris® may precipitate bleeding from the inflamed pancreas. OBJECTIVE: This study tests the hypothesis that Xigris® can ameliorate experimental acute pancreatitis without causing pancreatic haemorrhage. METHODS: Sprague Dawley rats were allocated as follows: Group 1: control (n=7); Group 2: acute pancreatitis (n=6); Group 3: administration of Xigris® 500 µg/kg body weight before induction of acute pancreatitis (n=6); and Group 4: Administration of Xigris® 500 µg/kg body weight 30 minutes after induction of acute pancreatitis (n=6). Acute pancreatitis was induced by intraperitoneal administration of L-arginine 300 mg/100 g body weight. Animals were sacrificed at 48 hours and biochemical, haematological, and histological markers of pancreatic haemorrhage and inflammation assessed. RESULTS: Median lipase in animals with acute pancreatitis was 10 U/mL (range: 7-16 U/mL) compared to 5.5 (range: 3-8 U/mL) in controls (P=0.028). Lipase was also elevated in animals given Xigris® both before (12 U/mL, range: 8-22 U/mL; P=0.031 vs. control group) and after (46 U/mL, range: 9-71 U/mL; P=0.015 vs. control group) induction of acute pancreatitis). Haemoglobin levels were similar among all groups (P=0.323). There was no histological evidence of pancreatic haemorrhage in animals treated with Xigris®. Pre-treatment with Xigris® was associated with a significant reduction in pancreatic injury. This effect was absent when Xigris® was administered after induction of acute pancreatitis. CONCLUSION: Xigris® did not lead to pancreatic haemorrhage in experimental acute pancreatitis. Administration of Xigris® prior to induction of acute pancreatitis was associated with amelioration of injury. This effect was not seen with administration of Xigris® after induction of acute pancreatitis.


Subject(s)
Anti-Infective Agents/pharmacology , Pancreas/drug effects , Pancreatitis/prevention & control , Protein C/pharmacology , Acute Disease , Amylases/blood , Animals , Anti-Infective Agents/administration & dosage , Anti-Infective Agents/adverse effects , Arginine , Hemorrhage/chemically induced , Humans , Injections, Intraperitoneal , Lipase/blood , Male , Pancreas/blood supply , Pancreas/pathology , Pancreatic Diseases/chemically induced , Pancreatic Diseases/diagnosis , Pancreatitis/blood , Pancreatitis/chemically induced , Protein C/administration & dosage , Protein C/adverse effects , Rats , Rats, Sprague-Dawley , Recombinant Proteins/administration & dosage , Recombinant Proteins/adverse effects , Recombinant Proteins/pharmacology , Treatment Outcome
6.
Biochim Biophys Acta ; 1689(3): 182-9, 2004 Aug 04.
Article in English | MEDLINE | ID: mdl-15276644

ABSTRACT

Autoimmune hepatitis (AIH) is a chronic liver disease of unknown aetiology characterized by circulating autoantibodies, hyperglobulinaemia and interface hepatitis. The mechanisms of progression from initial autoimmune attack to fibrosis and cirrhosis are unclear but oxidant stress may be involved. Markers of lipid peroxidation, antioxidant status, hepatic fibrogenesis and liver function were measured in blood and urine in 35 controls and in 33 patients with type-1 AIH; histology was assessed in 18 patients. In AIH, markers of lipid peroxidation were significantly elevated (8-isoprostane in both plasma and urine P < 0.001; plasma malondialdehyde P = 0.017). Total antioxidant capacity in protein-free serum and total glutathione in both whole blood and plasma were significantly reduced (P = 0.007, P = 0.037, P < 0.001, respectively). The antioxidants selenium, vitamin A and vitamin E were significantly decreased (P = 0.007, P < 0.001, P = 0.025, respectively); vitamin C was unchanged. Urinary 8-isoprostane correlated positively with interface hepatitis and necroinflammatory score and with hepatic fibrogenesis (type III procollagen peptide). Interface hepatitis correlated negatively with vitamin A and whole blood total glutathione. Oxidant stress, as reflected in blood and urine by a wide range of pro- and antioxidant markers, is a significant feature of AIH and provides a probable mechanism linking hepatic necroinflammation to fibrogenesis and disease progression.


Subject(s)
Hepatitis, Autoimmune/etiology , Liver Cirrhosis/complications , Oxidative Stress , Humans , Necrosis
7.
Kidney Int ; 64(5): 1755-64, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14531808

ABSTRACT

BACKGROUND: We have previously shown that the rat kidney reabsorbs metabolically significant amounts of iron and that it expresses the divalent metal transporter 1, DMT1. The Belgrade (b) rat carries a mutation in DMT1 gene, which causes hypochromic, microcytic anemia due to impaired intestinal iron absorption and transport of iron out of the transferrin cycle endosome. In the duodenum of b/b rats, expression of DMT1 mRNA and protein is increased, suggesting a feedback regulation by iron stores. The aim of this study was to investigate iron handling and DMT1 expression in the kidneys of Belgrade rats. METHODS: Animals were maintained for 3 weeks on a synthetic diet containing 185 mg/kg iron (FeSO4), after which functional and molecular parameters were analyzed in male heterozygous (+/b) and homozygous (b/b) rats (N = 4 to 6 for each group). RESULTS: Serum iron concentration was significantly higher in b/b compared to +/b rats while urinary iron excretion rates were unchanged in b/b compared to +/b rats. Northern analysis using a rat DMT1 probe showed comparable mRNA levels between +/b and b/b animals. Western analysis and immunofluorescence microscopy performed using a polyclonal antibody against rat DMT1 showed that DMT1-specific immunoreactivity was almost absent in the kidneys of b/b rats compared to that seen in +/b animals. CONCLUSION: Our results indicate that the G185R mutation of DMT1 causes protein instability in the kidneys of b/b rats. Given that +/b and b/b rats excrete comparable amounts of iron, the lack of DMT1 protein is compensated by an alternative, yet to be identified, mechanism.


Subject(s)
Anemia/metabolism , Cation Transport Proteins/genetics , Cation Transport Proteins/metabolism , Iron-Binding Proteins/genetics , Iron-Binding Proteins/metabolism , Iron/blood , Iron/urine , Kidney/metabolism , Anemia/pathology , Animals , Drinking , Eating , Feces , Female , Kidney/pathology , Magnesium/blood , Male , Point Mutation , Potassium/blood , RNA, Messenger/analysis , Rats , Rats, Mutant Strains , Urine
8.
J Pathol ; 200(5): 647-55, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12898602

ABSTRACT

Several mediators of systemic vasodilatation in liver cirrhosis have been reported. Among these is nitric oxide (NO), which has been proposed as one of the main mediators. In this study, sera and liver biopsies were analysed from 15 patients with clinically and pathologically diagnosed liver cirrhosis. In addition, sera from seven and liver biopsies from three healthy controls were used. Serum levels of nitrite (the end product of NO) were measured using the Griess reaction and the expression of the inducible nitric oxide synthase (iNOS) and constitutive nitric oxide synthase (ecNOS) proteins was investigated using immunohistochemistry. This study shows that serum nitrite levels (94 +/- 9.8 micro mol/l) in cirrhotic patients were significantly (p < 0.05) increased in comparison with the controls (36.6 +/- 11.03 micro mol/l). iNOS was completely absent from the control group but was highly expressed in the livers from the cirrhotic group. iNOS was seen mainly in the inflammatory cells infiltrating the portal tracts, blood monocyte-like cells, hepatocytes, sinusoidal cells, and endothelial cells. However, expression of ecNOS was only seen in the vascular endothelial cells of both the control and the cirrhotic groups, but was much higher in the latter. It is therefore clear that NO is augmented in cirrhotic patients and it is mainly produced by induction of iNOS. Moreover, NO up-regulation is dependent on the inflammatory stage of liver cirrhosis. ecNOS production could be a normal chronic adaptation mechanism of the endothelium to the chronically increased splanchnic blood flow secondary to portal hypertension. In the near future, the appropriate inhibition of NO activity by using NOS-active agents may provide a novel strategy for the treatment of patients with liver cirrhosis.


Subject(s)
Liver Cirrhosis/enzymology , Nitric Oxide Synthase/metabolism , Adult , Aged , Endothelium, Vascular/enzymology , Female , Humans , Immunoenzyme Techniques , Liver Cirrhosis/blood , Liver Cirrhosis/pathology , Male , Middle Aged , Nitric Oxide Synthase Type II , Nitric Oxide Synthase Type III , Nitrites/blood , Protein Isoforms/metabolism
9.
Am J Physiol Renal Physiol ; 285(6): F1050-9, 2003 Dec.
Article in English | MEDLINE | ID: mdl-12876064

ABSTRACT

Divalent metal transporter1 (DMT1; also known as DCT1 or NRAMP2) is an important component of the cellular machinery responsible for dietary iron absorption in the duodenum. DMT1 is also highly expressed in the kidney where it has been suggested to play a role in urinary iron handling. In this study, we determined the effect on renal DMT1 expression of feeding an iron-restricted diet (50 mg/kg) or an iron-enriched diet (5 g/kg) for 4 wk and measured urinary and fecal iron excretion rates. Feeding the low-iron diet caused a reduction in serum iron concentration and fecal iron output rate with an increase in renal DMT1 expression. Feeding an iron-enriched diet had the converse effect. Therefore, DMT1 expression in the kidney is sensitive to dietary iron intake, and the level of expression is inversely related to the dietary iron content. Changes in DMT1 expression occurred intracellularly in the proximal tubule and in the apical membrane and subapical region of the distal convoluted tubule. Increased DMT1 expression was accompanied by a decrease in urinary iron excretion rate and vice versa when DMT1 expression was reduced. Together, these findings suggest that modulation of renal DMT1 expression may influence renal iron excretion rate.


Subject(s)
Cation Transport Proteins/metabolism , Iron, Dietary/pharmacokinetics , Iron-Binding Proteins/metabolism , Kidney/metabolism , Animals , Cation Transport Proteins/biosynthesis , Diet , Immunohistochemistry , Iron, Dietary/urine , Iron-Binding Proteins/biosynthesis , Kidney/drug effects , Male , Rats , Rats, Wistar
10.
Biochim Biophys Acta ; 1637(2): 142-50, 2003 Mar 20.
Article in English | MEDLINE | ID: mdl-12633902

ABSTRACT

Primary biliary cirrhosis (PBC) is a chronic cholestatic disorder characterised by an immunological, and often granulomatous, attack on bile ducts leading to fibrosis, cirrhosis, liver failure and death. Animal and human studies suggest that oxidant stress plays a key role in progression of other liver diseases, but no comprehensive investigation has been performed previously in PBC. A wide range of lipid peroxidation and antioxidant markers were measured in the blood and urine of 41 patients with histologically confirmed PBC. Lipid peroxidation markers were significantly elevated [plasma and urinary 8-isoprostane, P<0.001; plasma malondialdehyde (MDA), P=0.007] compared to age- and sex-matched controls. The most striking antioxidant depletion occurred with plasma total glutathione where levels were significantly reduced (30% of controls). Total serum antioxidant levels were decreased (P=0.013) and serum selenium and vitamin A were also lower (both P<0.001); vitamins C and E were normal. Most patients had early disease biochemically and were Child-Pugh grade A. Urinary 8-isoprostane correlated positively with Ludwig stage and markers of hepatic injury and cholestasis. This study clearly demonstrates that oxidant stress, as reflected in a comprehensive spectrum of lipid peroxidation and antioxidant markers, is a significant feature of early-stage PBC.


Subject(s)
Dinoprost/analogs & derivatives , Liver Cirrhosis, Biliary/metabolism , Oxidative Stress , Antioxidants/analysis , Ascorbic Acid/blood , Biomarkers/blood , Biomarkers/urine , Cholestasis/pathology , F2-Isoprostanes/blood , F2-Isoprostanes/urine , Glutathione/blood , Humans , Lipid Peroxidation , Liver/pathology , Liver Cirrhosis, Biliary/blood , Liver Cirrhosis, Biliary/urine , Malondialdehyde/blood , Oxidants/blood , Oxidants/urine , Selenium/blood , Vitamin A/blood , Vitamin E/blood
11.
J Hepatol ; 36(6): 805-11, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12044532

ABSTRACT

BACKGROUND/AIMS: Chronic hepatitis C infection is a major world-wide problem, frequently progressing to cirrhosis, liver failure or hepatoma. The pathological mechanisms of disease progression are unclear but oxidant stress may play a role. METHODS: Markers of lipid peroxidation, antioxidant status, hepatic fibrogenesis and liver function were measured in blood or urine from 42 chronic hepatitis C patients. Fibrosis was graded histologically in a subgroup of 33 patients. RESULTS: The lipid peroxidation marker 8-isoprostane and the ratio of oxidized to reduced glutathione were significantly elevated (P<0.001, P=0.006). The antioxidants glutathione, selenium and vitamins A, C and E were significantly decreased (all P<0.001) compared to age and sex matched controls. Abnormal values were more marked in cirrhotics, but significant changes were also observed in the non-cirrhotic group. The fibrosis score correlated positively with urinary 8-isoprostane and type III procollagen peptide and negatively with vitamin A. CONCLUSIONS: Oxidant stress, as reflected in blood and urine by a wide range of pro- and antioxidant markers, is a significant feature of hepatitis C infection. Although more severe in the cirrhotic group, there was clear evidence of oxidant stress in non-cirrhotic patients. Antioxidant therapy may therefore have a role in slowing disease progression to cirrhosis.


Subject(s)
Dinoprost/analogs & derivatives , Hepatitis C, Chronic/metabolism , Oxidative Stress , Adult , Aged , Antioxidants/metabolism , Ascorbic Acid/metabolism , F2-Isoprostanes/metabolism , Female , Glutathione/metabolism , Humans , Lipid Peroxidation , Liver Cirrhosis/metabolism , Male , Middle Aged , Selenium/metabolism , Vitamin A/metabolism , Vitamin E/metabolism
13.
J Virol Methods ; 99(1-2): 53-61, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11684303

ABSTRACT

Hepatitis C virus (HCV) is a major cause of chronic hepatitis with liver-related death occurring in 20-25% of patients who develop cirrhosis. Detection of the virus RNA in liver is difficult since viral expression is very low. In situ polymerase chain reaction (PCR) in situ hybridisation (ISH) was developed for detection and localisation of viral RNA in formalin-fixed, paraffin-embedded liver tissue. Nested PCR technology was adapted for in situ use employing primers derived from the 5' end of the HCV genome. Seventeen liver blocks from known HCV-infected patients were examined. Viral RNA was detected in liver from eleven patients using solution phase reverse transcriptase-PCR. Of these positive samples, ten were positive by the in situ method. Positive signal was detected in the cytoplasm of hepatocytes and mononuclear cells. No Kupffer cell or bile duct epithelial positivity was observed. No positive signal was evident in any of the negative controls. A reliable method is described to demonstrate the presence and localisation of HCV RNA in liver tissue using an in situ PCR-ISH assay and it is believed that this will be a valuable tool for the understanding of HCV replication and pathogenesis.


Subject(s)
Hepacivirus/isolation & purification , Hepatocytes/virology , In Situ Hybridization/methods , Liver/virology , Polymerase Chain Reaction/methods , RNA, Viral/analysis , Hepacivirus/genetics , Hepatitis C, Chronic/virology , Humans
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