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BACKGROUND AND AIMS: Few data are available regarding the combination of biologics or small molecules in inflammatory bowel disease (IBD) patients. We report safety and efficacy of such combinations through a retrospective multicentre series. METHODS: Combination therapy was defined as the concomitant use of two biologics or one biologic with a small molecule. Patient demographics, disease characteristics and types of combinations were recorded. Safety was evaluated according to the occurrence of serious infection, opportunistic infection, hospitalisation, life-threatening event, worsening of IBD or immune-mediated inflammatory diseases (IMID), cancer and death. Efficacy was evaluated as the physician global assessment of the combination and comparison of clinical/endoscopic scores of IBD/IMID activity prior and during combination. RESULTS: A total of 104 combinations were collected in 98 patients. Concomitant IMID were present in 41 patients. Reasons for starting combination therapy were active IBD (67%), active IMID or extra-intestinal manifestations (EIM) (22%), both (10%) and unclassified in 1. Median duration of combination was 8 months (interquartile range 5-16). During 122 patient-years of follow-up, 42 significant adverse events were observed, mostly related to uncontrolled IBD. There were 10 significant infections, 1 skin cancer and no death. IBD disease activity was clinically improved in 70% and IMID/EIM activity in 81% of the patients. Overall, combination was continued in 55% of the patients. CONCLUSIONS: Combination of biologics and small molecules in patients with IBD and IMID/EIM seems to be a promising therapeutic strategy but is also associated with a risk of opportunistic infections or infections leading to hospitalisation in 10%. ispartof: UNITED EUROPEAN GASTROENTEROLOGY JOURNAL vol:9 issue:10 pages:1136-1147 ispartof: location:England status: published

Aim: Crohn's anal fistula (CAF) is a complex condition, with no agreement on which patient characteristics should be routinely reported in studies. The aim of this study was to develop a core descriptor set of key patient characteristics for reporting in all CAF research.Method: Candidate descriptors were generated from published literature and stakeholder suggestions. Colorectal surgeons, gastroenterologists and specialist nurses in inflammatory bowel disease took part in three rounds of an international modified Delphi process using nine-point Likert scales to rank the importance of descriptors. Feedback was provided between rounds to allow refinement of the next ratings. Patterns in descriptor voting were assessed using principal component analysis (PCA). Resulting PCA groups were used to organize items in rounds two and three. Consensus descriptors were submitted to a patient panel for feedback. Items meeting predetermined thresholds were included in the final set and ratified at the consensus meeting.Results: One hundred and thirty three respondents from 22 countries completed round one, of whom 67.0% completed round three. Ninety seven descriptors were rated across three rounds in 11 PCA-based groups. Forty descriptors were shortlisted. The consensus meeting ratified a core descriptor set of 37 descriptors within six domains: fistula anatomy, current disease activity and phenotype, risk factors, medical interventions for CAF, surgical interventions for CAF, and patient symptoms and impact on quality of life.Conclusion: The core descriptor set proposed for all future CAF research reflects characteristics important to gastroenterologists and surgeons. This might aid transparent reporting in future studies.

BACKGROUND: Improving treatment outcomes with biological therapy is a demanding current need for patients with inflammatory bowel disease. Discovery of pretreatment prognostic indicators of response may facilitate patient selection and increase long-term remission rates. We aimed to identify baseline mucosal gene expression profiles with predictive value for subsequent response to or failure of treatment with the monoclonal antibody against integrin α4β7, vedolizumab, in patients with active ulcerative colitis (UC). METHODS: Mucosal expression of 84 immunological and inflammatory genes was quantified in RNA extracted from colonic biopsies before vedolizumab commencement and compared between patients with or without response to treatment. Significantly differentiated genes were further validated in a larger patient cohort and within available public data sets, and their functional profiles were studied accordingly. RESULTS: In the discovery cohort, we identified 21 genes with a statistically significant differential expression between 54-week responders and nonresponders to vedolizumab. Our validation study allowed us to recognize a "core" mucosal profile that was preserved in both discovery and validation cohorts and in the public database. The applied functional annotation and analysis revealed candidate dysregulated pathways in nonresponders to vedolizumab, including immune cell trafficking, TNF receptor superfamily members mediating noncanonical NF-kB pathway, in addition to interleukin signaling, MyD88 signaling, and toll-like receptors (TLRs) cascade. CONCLUSIONS: Nonresponse to vedolizumab in UC is associated with specific pretreatment gene-expression mucosal signatures and dysregulation of particular immunological and inflammatory pathways. Baseline mucosal and/or systemic molecular profiling may help in the optimal stratification of patients to receive vedolizumab for active UC. © 2021 Crohn’s & Colitis Foundation. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Background: Optimization of treatment with biologics is currently an unmet need for patients with ulcerative colitis (UC). Real-world studies provide neutral estimates of drug efficacy and safety within unselected patient populations and allow for the recognition of specific characteristics that affect response to therapy. Aims: We aimed to depict the efficacy of vedolizumab in patients with UC in a real-world setting and identify prognosticators of improved outcomes. Methods: Patients with active UC who commenced treatment with vedolizumab were prospectively followed up. Patient-reported outcomes (PROs) and clinical/endoscopic-reported outcomes were recorded at baseline and at weeks 14 and 54. Predefined endpoints of early and persistent efficacy were analyzed against clinical characteristics to identify prognostic factors for response. Results: We included 96 patients (anti-TNF-exposed = 38.5%). At week 14, 73 patients (76%) had clinical response and 54 (56.3%) clinical remission. At week 54, the primary endpoint of vedolizumab persistence was met by 72 patients (75%), whereas steroid-free clinical remission by 59.4%. Among patients who had endoscopy, rates for mucosal healing (Mayo endoscopic score of 0) were 29.8% at week 14 and 44.6% at week 54, respectively. Vedolizumab treatment led to significant improvements in quality of life. Corticosteroid-refractory or anti-TNF-refractory disease, articular manifestations, and high baseline UC-PRO2 were associated with decreased efficacy of vedolizumab in the primary and secondary outcomes. Conclusions: Vedolizumab is characterized by high efficacy and long-term treatment persistence in UC. More aggressive disease, as indicated by refractoriness to steroids or anti-TNFs and elevated baseline PROs, may predict suboptimal response and help pre-treatment prognostic stratification of patients. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.

OBJECTIVES: COVID-19 has evolved into a global health crisis, variably affecting the management of patients with chronic illnesses. Patients with inflammatory bowel disease (IBD) may represent a vulnerable population due to frequent administration of immune-modifying treatments. We aimed to depict the natural history of COVID-19 infection in Greek patients with IBD at a nationwide level via unbiased reporting of all cases that were registered during the sequential waves of the pandemic. METHODS: Following a national call from the Hellenic Society for the study of IBD, we enrolled all IBD patients with established diagnoses of COVID-19. Clinical and epidemiological data, including COVID-19 modifying factors and IBD-associated therapies, were analyzed against adverse outcomes (hospitalization, ICU admission and death). RESULTS: We identified 154 IBD patients who were diagnosed with COVID-19 (men: 58.4%; mean age=41.7 years [SD = 14.9]; CD: 64.3%). Adverse outcomes were reported in 34 patients (22.1%), including 3 ICU admissions (1.9%) and two deaths (1.3%). Multivariate logistic regression analysis showed that age (OR = 1.04, 95% CI, 1-1.08) and dyspnea at presentation (OR = 7.36, 95% CI, 1.84-29.46) were associated with worse outcomes of COVID-19 infection. In contrast, treatment with biologics, in particular anti-TNF agents, exerted a protective effect against an unfavorable COVID-19 disease course (OR = 0.4, 95% CI, 0.16-0.99). Patients on subcutaneous biologics were more likely to halt treatment due to the infection as compared to those on intravenous biologics. CONCLUSIONS: IBD patients who developed COVID-19 had a benign course with adverse outcomes being infrequent. Treatment with anti-TNF biologics had a protective effect, thus, supporting continuation of therapy during the pandemic. Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.

Objective The LRG, HMGB1, MMP3 and ANXA1 proteins have been implicated in different inflammatory pathways in ulcerative colitis (UC), but their role as specific biomarkers of both endoscopic and histological activity has yet to be elucidated. In the present study, we aimed to evaluate the LRG1, HMGB1, MMP3 and ANXA1 as potential serum biomarkers for UC endoscopic and histological activity. Methods This cross-sectional study included UC patients under 5-ASA, and healthy controls (HC) undergoing colonoscopy. Blood and biopsy samples were obtained and endoscopic Mayo sub-score (Ms) was recorded for the UC patients. Intramucosal calprotectin as a marker of histologic activity was evaluated in all biopsy samples and serum LRG1, HMGB1, MMP3 and ANXA1 levels were measured in the blood samples. Results The HCs ANXA1 level was lower compared to that of the UC group [P = 0.00, area under the curve (AUC) = 0.881] and so was the HCs MMP3 level compared to that of patients (P = 0.00, AUC = 0.835). The HCs ANXA1 levels were also lower compared to these of the independent Ms groups, even to the Ms = 0 (P = 0.00, AUC = 0.913). UC endoscopic activity was associated with MMP3 levels (r = 0.54, P = 0.000) but not with ANXA1, LRG1 and HMGB1 levels Conclusion Serum ANXA1 is a potential diagnostic biomarker of UC and serum MMP3 is a potential biomarker of UC endoscopic and histological activity. © 2020 Lippincott Williams and Wilkins. All rights reserved.

Even though anti-TNF therapy significantly improves the rates of remission in inflammatory bowel disease (IBD) patients, there is a noticeable subgroup of patients who do not respond to treatment. Dysbiosis emerges as a key factor in IBD pathogenesis. The aim of the present study is to profile changes in the gut microbiome and transcriptome before and after administration of the anti-TNF agent Infliximab (IFX) and investigate their potential to predict patient response to IFX at baseline. Mucosal biopsy samples from 20 IBD patients and nine healthy controls (HC) were examined for differences in microbiota composition (16S rRNA gene sequencing) and mucosal gene expression (RT-qPCR) at baseline and upon completion of IFX treatment, accordingly, via an in silico pipeline. Significant differences in microbiota composition were found between the IBD and HC groups. Several bacterial genera, which were found only in IBD patients and not HC, had their populations dramatically reduced after anti-TNF treatment regardless of response. Alpha and beta diversity metrics showed significant differences between our study groups. Correlation analysis revealed six microbial genera associated with differential expression of inflammation-associated genes in IFX treatment responders at baseline. This study shows that IFX treatment has a notable impact on both the gut microbial composition and the inflamed tissue transcriptome in IBD patients. Importantly, our results identify enterotypes that correlate with transcriptome changes and help differentiate IFX responders versus non-responders at baseline, suggesting that, in combination, these signatures can be an effective tool to predict anti-TNF response. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

Background: To compare the clinical, serological and histologic features between male and female patients with Sjögren’s syndrome (SS) and explore the potential effect of gender on lymphoma development. Methods: From a multicenter population (Universities of Udine, Pisa and Athens, Harokopion and Ioannina (UPAHI)) consisting of consecutive SS patients fulfilling the 2016 ACR/EULAR criteria, male patients were identified, matched and compared with female controls. Data-driven multivariable logistic regression analysis was applied to identify independent lymphoma-associated factors. Results: From 1987 consecutive SS patients, 96 males and 192 matched female controls were identified and compared. Males had a higher frequency of lymphoma compared to females (18% vs. 5.2%, OR = 3.89, 95% CI: 1.66 to 8.67; p = 0.0014) and an increased prevalence of serum anti-La/SSB antibodies (50% vs. 34%, OR = 1.953, 95% CI: 1.19 to 3.25; p = 0.0128). No differences were observed in the frequencies of lymphoma predictors between the two genders. Data-driven multivariable logistic regression analysis revealed negative association of the female gender with lymphoma and positive association with lymphadenopathy. Conclusion: Male SS patients carry an increased risk of lymphoma development. Although statistics showed no difference in classical lymphoma predictors compared to females, data-driven analysis revealed gender and lymphadenopathy as independent lymphoma-associated features. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

Background: We sought to compare clinical outcomes of concomitant cholecystectomy during four different types of bariatric surgery vs. bariatric surgery alone. Data sources: A systematic literature search of PubMed and Cochrane databases was conducted in accordance with the PRISMA guidelines. Thirty studies were included in this study, reporting data on 13,675 patients. Our findings suggest a higher rate of anastomotic leak/stricture in the case of concomitant cholecystectomy with gastric bypass compared to those who had gastric bypass alone. The scarcity of data concerning sleeve gastrectomy, adjustable gastric banding and biliopancreatic diversion prevented us from quantifying possible difference of outcomes between the examined treatment groups. Conclusions: This study highlights the small number and poor quality of available studies referring to the role of simultaneous cholecystectomy during bariatric surgery. © 2019 Elsevier Inc.

Unambiguously, great progress has been achieved in the unraveling of more pathological pathways implicated in the development and progression of ulcerative colitis during the last decades. Novel effective drugs that have augmented the management armamentarium have been developed alongside this growing comprehension of the disease, rendering mucosal healing not only a feasible but the optimal goal of every therapy. Clinical evaluation, colonoscopy and biomarkers are the tools used by practitioners for the diagnosis and assessment of the status of the disease in order to achieve clinical remission and mucosal healing for their patients. Among these tools, colonoscopy is the gold method for the cause but is still an invasive, high-cost procedure with possible adverse events such as perforation. While clinical evaluation entails much subjectivity, biomarkers are objective, easily reproducible, non-invasive, cheap and potent surrogate tools of mucosal inflammation. Unfortunately, the well-established, currently in use serum biomarkers, such as C-reactive protein, erythrocyte sedimentation rate and others, do not display sufficiently acceptable sensitivity and specificity rates for the diagnosis of ulcerative colitis and, most importantly, do not represent precisely the mucosal inflammation status of the disease. Therefore, the discovery of new serum biomarkers has been the cause of several studies attempting to discover an “optimal” serum biomarker during the recent years. After thorough research, collection and examination of current data, this review focuses on and selectively presents promising, potential, novel serum biomarkers of ulcerative colitis as they are indicated by studies on the patient over the last years. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Background: The optimal treatment for advanced heart failure (HF) patients with regards to mortality remains unknown. Heart transplantation (HTx) and left ventricular assist devices (LVAD) used either as a bridge to transplant (BTT) or destination therapy (DT) have been compared in a number of studies, without definite conclusions with regards to mortality benefit. We sought to systematically review the pertinent literature and perform a meta-analysis of all the available studies presenting head-to-head comparisons between HTx and LVAD BTT or LVAD DT for late ( > 6 months) all-cause mortality. Methods: We performed a systematic search of Medline and Cochrane Central databases in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We conducted a meta-analysis of late mortality comparing HTx vs. BTT LVAD and HTx vs. DT LVAD using a random effects model. Results: Eight studies were included in our meta-analysis, reporting data on 7,957 patients in total. Although the available studies are of high quality [8 stars in Newcastle-Ottawa Scale (NOS) on average], there is paucity of mortality data. Specifically, seven studies compared HTx with BTT and five studies compared HTx with DT for 1-year mortality. Our pooled estimates showed that there was no difference in late mortality among these strategies. Conclusions: Our meta-analysis highlights the small number and the heterogeneity of available studies referring to the optimal invasive management of advanced HF, and shows that there are no differences between HTx and LVAD for these patients with regards to late mortality. © Annals of Cardiothoracic Surgery.

Live commensal intestinal bacteria are present in the peripheral blood where they can induce inflammation. Objective To evaluate the intestinal bacteria composition and translocation of bacteria in IBD. Methods Both blood and tissue biopsy samples were collected from adult patients with active/inactive Crohn's disease (CD), active/inactive ulcerative colitis (UC) and healthy individuals. Most of the patients were newly diagnosed and none of them received antibiotics. Using a reverse transcription-quantitative real-time PCR (RT-qPCR) method, we determined the composition of microbiota. NOD2/CARD15 genotyping was also studied. Results Total bacterial DNA concentration was increased in tissue and blood samples of IBD patients compared to healthy controls. Furthermore, the active IBD cases had higher total bacterial DNA concentration levels compared to the inactive cases. Three species characterized dysbiosis in IBD, namely an increase of Bacteroides spp in active and inactive IBD samples, and a decrease in Clostridium leptum group (IV), and Faecalibacterium prausnitzi in both active and inactive IBD patients. No significant association between bacterial translocation and NOD2/CARD15 mutations was found. Conclusions The composition of the microbiota in IBD patients differs from that of healthy controls. The high rate of bacterial DNA in the blood samples indicates translocation in inflammatory bowel disease. © Copyright 2017 Liu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

The Macedonian Question has attracted much attention since the 1990s due to the emergence of the dispute over the name of Macedonia between Greece and the Republic of Macedonia. In Greece there is a prolific literature on this subject, but some basic questions remain unanswered. In particular, the role of the government, and of government institutions – especially the Ministry of Foreign Affairs – have attracted little or no attention: on the contrary, historians have focused on the 'heroes' of the conflict, the fighters themselves, the result being that the Macedonian Question is understood as a military fight of good versus evil. In this D.Phil. thesis, we examine how the government got involved with the Macedonian Question and second, in what ways it was involved, especially given that an official acknowledgement of the government's involvement with the paramilitary operations was diplomatically impossible. We approached these questions by examining the personal archives of Greek politicians and diplomats (most notably of the Dragoumis family) and the Archives of the Ministry of Foreign Affairs, especially the Archives of the Greek Embassies in London, Paris and Constantinople, which have only recently become available. The key finding is that the Greek government, despite its declarations to the opposite effect, was involved heavily with the paramilitary fighting in Macedonia, but also that the official involvement with Macedonia was constrained and influenced by electoral concerns and by the powerful Macedonian lobbies in Athens. Decisions were rarely made in a rational, bureaucratic way, but were more often reached after consultations with journalists, military officers and intellectuals and always bearing domestic political realities in mind. These findings suggest that future research should move away from understanding the 'Macedonian Struggle' solely as a military issue, and put it into the wider context of early twentieth-century Greek political and diplomatic history.

Aim: To investigate CYP2E1 IgG4 autoantibody levels and liver biochemical markers in adult patients after anesthesia with desflurane. Methods: Forty patients who were > 18 years old and undergoing elective surgery under general anesthesia with desflurane were studied. Alpha-glutathione- S-transferase (aGST) and IgG4 antibodies against CYP2E1 were measured preoperatively and 96 h postoperatively, as well as complete blood count, prothrombin time (PT), activated partial thromboplastin time (aPTT), international normalized ratio (INR), aspartate aminotransferase (SGOT), alanine aminotransferase (SGPT), g-glutamyl-transpeptidase (gGT), alkaline phosphatase, total serum proteins, albumin and bilirubin. A separate group of 8 patients who received regional anesthesia was also studied for calibration of the methodology used for CYP2E1 IgG4 and aGST measurements. Student's t-test and the Mann-Whitney U test were used for comparison of the continuous variables, and Fisher's exact test was used for the categorical variables. All tests were two-tailed, with statistical significance set as P < 0.05. Results: None of the patients developed postoperative liver dysfunction, and all patients were successfully discharged from the hospital. No statistically significant difference was observed regarding liver function tests (SGOT, SGPT, ?GT, bilirubin, INR), aGST and CYP2E1 IgG4, before and after exposure to desflurane. After dividing patients into two subgroups based on whether or not they had received general anesthesia in the past, no significant difference in the levels of CYP2E1 IgG4 was observed at baseline or 96 h after desflurane administration (P = 0.099 and P = 0.051, respectively). Alpha-GST baseline levels and levels after the intervention also did not differ significantly between these two subgroups (P > 0.1). The mean aGST differences were statistically elevated in men by 2.15 ng/mL compared to women when adjusted for BMI, duration of anesthesia, number of times anesthesia was administered previously and length of hospital stay. No significant difference was observed between patients who received desflurane and those who received regional anesthesia at any time point. Conclusion: There was no difference in CYP2E1 IgG4 or aGST levels after desflurane exposure; further research is required to investigate their role in desflurane-induced liver injury. © 2014 Baishideng Publishing Group Inc.

Bcl-2 protein blocks apoptosis and is involved in human intrahepatic bile-duct development. Formalin-fixed, paraffin-embedded archival tissue from 42 HBV and HCV hepatitis [20 acute AH, 22 chronic hepatitis (CH)], 12 active cirrhosis (CR) and 20 hepatocellular carcinoma (HCC) was immunostained for bcl-2 protein. In all cases, bcl-2 protein was detected in portal and intralobular lymphocytes but not in hepatocytes or Kupffer cells. Bcl-2 was positive in the cytoplasm of small portal bile ducts of chronic hepatitis, while it was strongly expressed in newly formed bile-ductules of the limiting plate, mainly in CH with marked activity and CR. Bcl-2 was detected in small bile ducts in only one case of acute hepatitis and was not detected in any case of HCC. Bcl-2 seems to be involved in the regulation of growth and apoptosis of cholangiolar cells. Its expression in small bile ducts and in newly-formed ductules especially in CH with marked activity and CR, implies that the embryonic model of intrahepatic bile duct development may be recapitulated in chronic hepatic disease. Moreover, it supports evidence for the existence of the controversial long-lived stem population in the liver. Bcl-2 does not seem to be involved in hepatocarcinogenesis.

Administration of 2-acetylaminofluorene (2-AAF) given before a two-thirds partial hepatectomy (PHx), results in suppression of hepatocyte proliferation and stimulation of oval cell proliferation. Our objective in this study was to examine the oval cell response and associated alpha-fetoprotein (AFP) gene expression by combining 2-AAF with selective hepatic damage caused by either carbon tetrachloride (CCl4) exposure or by PHx. We also examined oval cell response with the above two protocols (2-AAF/CCl4 and 2-AAF/PHx) as affected by previous bile ductular damage caused by 4,4'-methylene dianiline (4,4'-diaminodiphenylmethane, DAPM) exposure. DAPM is an aromatic diamine, known to cause bile ductular damage in both humans and animals. Using the protocols of 2-AAF/ CCl4 and 2-AAF/PHx, when DAPM was given 24 hours before the hepatic injury, no oval cell proliferation was seen (histological) and AFP expression was not detected by Northern blot analysis. These results provide direct evidence that oval cells are closely associated with the biliary epithelial cells and supports the theory that hepatic oval cells may originate from cells derived from either intraportal or periportal ductules.

The ductular reaction to acute submassive necrosis was studied in human livers removed at the time of orthotopic liver transplantation. Single, double, and triple immunohistochemical labeling in combination with morphometry was used to analyze the phenotype and proliferative and apoptotic rates of various epithelial cell compartments. These were divided on the basis of immunohistochemistry and morphology into three subtypes: 1) CK19+/AE1+ mature bile duct epithelium, 2) HEP-PAR+ mature hepatocytes (HEPs), and 3) CK19+/AE1+ ductular hepatocyte (DH) cells lying at the interface between the portal tract connective tissue and the hepatic lobules. Cycling cells were defined as those showing Ki-67+ (MIB-1) nuclear labeling. Apoptotic cells were identified with in situ labeling using the terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick end labeling assay. Special emphasis was placed on DHs that appeared at the interface between the portal tracts and hepatic lobules. During the recovery phase from submassive hepatic necrosis, subtraction of the rate of cell death from the proliferative index shows that all of the epithelial compartments experience a net increase in the number of cells. The highest proliferation rate occurs in the DHs, which is significantly (P < 0.0001) higher than the proliferation rate seen in either the HEP or bile duct epithelium compartments. Immunohistochemical analysis of the highly proliferative DH compartment shows it to be a heterogeneous population with unique phenotypic features. Like epithelial cells in the ductal plate of fetal liver and cholangiocarcinomas, DHs are positioned on a laminin-rich matrix and focally express vimentin and Lewis(x) and show up-regulation of bcl-2 and type IV collagenase. However, unlike ductal plate cells, DHs are CD34 and alpha-fetoprotein negative. Although a subpopulation of DHs share phenotypic features with mature bile duct epithelium (AE1/cytokeratin 19 and type IV collagenase positive) or HEP (HEP-PAR, albumin, and alpha-1-antitrypsin positive), they are also clearly separate from both populations; DHs are negative or only weakly stain for glutathione-S-transferase-pi and are type IV collagenase positive. Moreover, occasional DHs also co-expressed HEP-PAR or alpha-1-antitrypsin and AE1, indicative of both hepatocyte and ductular differentiation. These findings suggest that DHs seen in human livers after submassive necrosis may represent a transient amplifying population arising from a progenitor population located in or near the canals of Herring. In addition, injured hepatocytes can express cytokeratin 19 and AE1, which normally are biliary intermediate filaments.

Hepatocyte growth factor, also known as scatter factor, is a complete mitogen for hepatocytes that bears sequence and structural homology with plasminogen. Because it exists in both a mitogenically inactive single-chain form and an active two-chain form, we were interested in determining whether plasminogen activators could properly cleave single-chain hepatocyte growth factor to generate active two-chain hepatocyte growth factor. Herein we report that both urokinase-type plasminogen activator and tissue-type plasminogen activator can cleave single-chain hepatocyte growth factor, generating two-chain hepatocyte growth factor. When equal quantities of plasminogen activator-treated and activator-untreated hepatocyte growth factor are compared in serum-free in vitro bioassays, the treated hepatocyte growth factor is mitotically more active. Also, urokinase-type plasminogen activator was inactive against hepatocyte growth factor molecules with a mutated cleavage site. This suggests that urokinase-type and tissue-type plasminogen activator may be natural biological regulators of hepatocyte growth factor. Because the active form of hepatocyte growth factor is a powerful stimulator of DNA synthesis and cell motility, these findings may be relevant in understanding the role of plasminogen activators in the biology of cancer invasion and metastasis.

The human proto-oncogene c-MET encodes a heterodimeric 190 kDa transmembrane protein (p190c-met) with structural features of a tyrosine kinase receptor. The ligand for this putative receptor has not yet been identified. By Northern blot hybridization we found that, among a restricted number of human tissues, c-MET is highly expressed in the liver. This prompted us to test the hypothesis of a functional interaction between the c-MET receptor and Hepatocyte Growth Factor (HGF), a heparin-binding polypeptide consisting of heavy and light chains of 65 and 35 kDa. Nanomolar concentrations of highly purified HGF added to GTL-16 cells, which overexpress the c-MET receptor, enhanced the phosphorylation on tyrosine of the p190c-met kinase. Addition of other known growth factors or serum was ineffective. The kinase activity of the c-MET receptor was also stimulated by HGF in an in vitro assay, after detergent solubilization and partial purification of p190c-met. Moreover, elution of immunoprecipitates obtained with anti-MET antibodies from GTL-16 cell lysates yielded an HGF-responsive kinase activity. These results suggest that HGF, or a growth factor structurally related to HGF, is a candidate ligand for the receptor encoded by c-MET.

Aldehyde dehydrogenase (ALDH) activity was measured in primary cultures of normal human hepatocytes and of the human hepatoma cell line HepG2 after application of phenobarbital (PB) or 3-methylcholanthrene (MC) for 5 days. Treatment with PB alone resulted in a significant increase in both protein and DNA content at concentrations of 2 and 3 mM. Treatment with MC at a concentration as low as 5 microM led to a significant loss of cells when it lasted more than 5 days. Concentrations of 3-5 mM of PB in the media of HepG2 cell cultures caused a 2-fold enhancement of the activity of ALDH, as measured with NAD and propionaldehyde (P/NAD) or benzaldehyde (B/NAD). On the other hand, MC-treated cultures (5 microM) showed a 20-fold increase in enzyme activity measured with NADP and benzaldehyde (B/NADP), and a 2-fold increase in B/NAD activity. Combined treatment with both PB and MC led to an effect of dynamic synergism as far as B/NAD and B/NADP activities are concerned, suggesting a metabolite of MC as the mediator for the increase of ALDH activity. Normal human hepatocytes in primary cultures responded to PB (3 mM) in a similar way as HepG2 cells as far as DNA and protein content and ALDH activity are concerned. It is concluded, that HepG2 hepatoma cells behave similar to the normal hepatocytes in terms of ALDH regulation and can be used for studies on the activity of ALDH as modified by added xenobiotics. Chem Biol Interact

Aldehyde dehydrogenase was measured in primary cultures of hepatocytes obtained with a two-step collagenase perfusion either from human hepatic tissue or from livers of Fisher rats. Basal enzyme activity declines gradually as a function of time in culture, but remains at all times higher when measured with propionaldehyde and NAD (P/NAD) than with benzaldehyde and NADP (B/NADP). Treatment of the cultures with 2 microM of 3-methylcholanthrene for four days significantly increased the B-NADP activity of human and rat hepatocytes (tenfold and eightfold respectively). In human hepatocytes 3-methylcholanthrene increases also the P/NAD activity, but to a lesser extent (twofold), compared to the B/NADP activity. Due to the significant enhancement of B/NADP activity in cultures of human and rat hepatocytes after application of 3-methylcholanthrene, the initial difference in the basal activity levels between the P/NAD and B/NADP forms diminishes or, in the case of human hepatocytes, is even inverted. These results show for the first time that aldehyde dehydrogenase activity is increased in cultured human hepatocytes. This biochemical property is preserved in human and rat hepatocyte cultures, despite the rather quick loss of the basal aldehyde dehydrogenase activity. Cell Biol Toxicol

Το καλοκαίρι του 1988 παρατηρήθηκε έξαρση της προσβολής των εσπεριδοειδών, και της σουλτανίνας σε μικρότερο βαθμό, από αλευρώδη. Η κύρια εστία εντοπίστηκε στην βορειοδυτική Πελοπόννησο. Στα δείγματα που λήφθηκαν από τις περιοχές Ξυλοκάστρου και Πύργου, διαπιστώθηκε η παρουσία του είδους Parabemisia myricae (Kuwana), για πρώτη φορά σε Ευρωπαϊκή χώρα. Ο αλευρώδης αυτός που ενδημεί σε γειτονικές χώρες της Βόρειας Αφρικής και της Μέσης Ανατολής προσβάλει ξυλώδη φυτά προκαλώντας κυρίως έμμεσες ζημιές από τις οποίες η σημαντικότερη είναι η ποιοτική υποβάθμιση των καρπών από την ανάπτυξη μυκήτων πάνω στα εκκρίματα του.Η βιολογία του έχει μελετηθεί σχετικά λίγο. Είναι γνωστό ότι τα θηλυκά γεννούν αποκλειστικά σε πολύ τρυφερή βλάστηση. Βρέθηκε ότι η γρήγορη ωρίμανση των φύλλων προκαλεί θνησιμότητα των ατελών μορφών. Αναφέρεται ότι ο βιολογικός του κύκλος στη διάρκεια του καλοκαιριού διαρκεί περί τις τρεις εβδομάδες., Citrus groves of Corfu had been attacked during the last decade by citrus whitefly Dialeurodes citri (Ashmead). It presumably expanded later, and it was found to cause a serious infestation on lemon trees of Achaia region during summer of 1986, while it disappeared later existing today only in very small pockets on ornamental citrus species in Attica area. Late in August 1988, the leaves of citrus trees, and to a lesser extent of grapevines, in the region of Corinthia, NE Peloponnesos, in South Greece were covered by larvae, pupae and adults of a whitefly that was different from D. citri. In autumn of the same year, it was noticed that the infestation of this new whitefly had expanded to other parts of Peloponnese such as Argos, Patras and Ilia region. Samples of citrus and grapevine leaves with nymphs of the insect were sent for identification to British Museum of Natural History. Dr. J. H. Martin identified the species as Parabemisia myricae (Kuwana) (Homoptera: Aleyrodidae), making the first record of the species in Greece. The species is a native of Japan and possibly of other eastern asian countries such as Taiwan and West Malaysia. Today, the insect has been recorded in USA (California), Cyprus, Israel and Turkey, Egypt (Martin personal communication) and it is a pest of woody plants, especially citrus trees and grapevines. The damage caused to the plants by this insect, as a feeder, can be serious in cases of large populations accompanied with problems associated with the development of sooty mould on the excreted honeydew. In the autumn of 1988, infestation was high (more than 20 nymphs/leaf) in Achaia and Corinthia regions of N. Peloponnese, causing great concern to citrus growers. This species of whitefly was not included in the lists of known plant pests of Greece. It is probable that it invaded Greece from Israel. P. myricae is a newly introduced pest in citrus growing countries and there is little information available on its biology and control. Most of the published data comes from Israel and California on the biology and biological control of the insect. Additional data have been published on flight behaviour, oviposition behaviour, and survival of young nymphs on leaves of different age citrus leaves. The adults of P. myricae are smaller than D. citri adults and they have a dusty blue gray or lavender appearance. The females oviposit on very young leaves, often in circles. Preference for oviposition on very young leaves seems to be related to properties of the leaf cuticle. Leaf age is a critical factor for survival of nymphs. This gives a good explanation for the observed high rates of mortality in spring for nymphs growing on rapidly maturing leaves. It has been observed that on orange trees less eggs are layed on the lower surface of the leaves, while on lemon trees they tend to be layed equally on both surfaces. Initially eggs are off-white, while after about one day they gradually turn to brownish and finally black, before they hatch. First instar crawlers settle on the surface of the young leaves with a preference to the lower surface. First flights of adults were noticed in this area in late February of 1989. By end of March early April the emergence of adults of the first 1989 generation had been completed. It seems that it produces a quite large number of generations during the year, as it requires only 21 days at temperatures fluctuating between 210oC and 17.3oC and 65-100 percent relative humidity, to complete its cycle in glasshouse. Being a pest of Citrus and grapevines (Vitis vinifera) it has also been found on hosts like Ficus, Persea, Prunus, Psidium and Thea. As a matter of fact it has also been found in small colonies on Prunus cerasi in Northern Peloponnese in autumn 1988. Work on the control of Parabemisia myricae with the insect growth regulator Buprofezin has started in Greece in 1988 and is expected to be concluded in 1990.

Aldehyde dehydrogenase (ALDH) was measured in primary cultures of hepatocytes obtained with collagenase perfusion from livers of Long-Evans rats. After seven days in culture, basal ALDH activity, protein content and DNA content are significantly decreased. Exposure of the cultures to phenobarbital (PB, 3 mM in the media) does not prevent the decrease of DNA content, although it keeps protein at relatively higher levels. The activity of ALDH is not only preserved, but also significantly enhanced, when propionaldehyde, phenylacetaldehyde, benzaldehyde and D-glucuronolactone are used as substrates and NAD as the coenzyme. A relative increase of activity is also noted when ALDH is measured with benzaldehyde and NADP. Treatment of Long-Evans animals with PB (1 mg/ml, in drinking water for 2 weeks) leads to similar relative increases of the ALDH activity. In absolute values, however, enzyme activities found after in vivo treatment with PB are higher, compared to those obtained after in vitro exposure. These results show that ALDH activity can be greatly enhanced by PB in primary hepatocyte cultures, free from any indirect endogenous influences. Acta Pharmacol Toxicol (Copenh)

The activity of aldehyde dehydrogenase (ALDH) was measured in primary and metastatic human colonic adenocarcinomas. The enzyme was determined with either propionaldehyde and NAD (P-NAD) or with benzaldehyde and NADP(B-NADP). Primary colonic adenocarcinomas had levels of P-NAD activity similar to those of the adjacent normal mucosa, but relatively higher B-NADP activity. Also the metastatic colonic adenocarcinomas of the liver had lower P-NAD and higher B-NADP activity than the normal hepatic parenchyma. The level of ALDH was in general lower in the normal colonic mucosa, when compared to the liver. Histochemical staining of cryostat tissue sections revealed that the enzyme is exclusively confined to the epithelial cells of the glandular ducts of the colonic mucosa. This may explain, along with the significant anaplastic changes of the mucosa, the variation of ALDH activity detected in the homogenates of the primary and metastatic adenocarcinomas. However, the ratio of B-NADP activity in the adenocarcinomas versus the adjacent normal tissues was constantly and significantly high. Cancer Lett