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Oral vancomycin is associated with improved inflammatory bowel disease clinical outcomes in primary sclerosing cholangitis-associated inflammatory bowel disease (PSC-IBD): A matched analysis from the Paediatric PSC Consortium. Aliment Pharmacol Ther 2024; 59:1236-1247. [PMID: 38462727 DOI: 10.1111/apt.17936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 09/18/2023] [Accepted: 02/22/2024] [Indexed: 03/12/2024]
Abstract
BACKGROUND Data on oral vancomycin for primary sclerosing cholangitis (PSC)-associated inflammatory bowel disease (IBD) are limited. AIMS Using data from the Paediatric PSC Consortium, to examine the effect of vancomycin on IBD activity. METHODS In this retrospective multi-centre cohort study, we matched vancomycin-treated and untreated patients (1:3) based on IBD duration at the time of primary outcome assessment. The primary outcome was Physician Global Assessment (PGA) of IBD clinical activity after 1 year (±6 months) of vancomycin. We used generalised estimating equations (GEE) to examine the association between vancomycin and PGA remission, adjusting for IBD type, severity and medication exposures. Secondary outcomes included serum labs and endoscopic remission (global rating of no activity) among those with available data and also analysed with GEE. RESULTS 113 PSC-IBD patients received vancomycin (median age 12.7 years, 63% male). The matched cohort included 70 vancomycin-treated and 210 untreated patients. Vancomycin was associated with greater odds of IBD clinical remission (odds ratio [OR] 3.52, 95% CI 1.97-6.31; adjusted OR [aOR] 5.24, 95% CI 2.68-10.22). Benefit was maintained in sensitivity analyses restricted to non-transplanted patients and those with baseline moderate-severe PGA. Vancomycin was associated with increased odds of endoscopic remission (aOR 2.76, 95% CI 1.002-7.62; N = 101 with data), and with lower CRP (p = 0.03) and higher haemoglobin and albumin (both p < 0.01). CONCLUSION Vancomycin was associated with greater odds of IBD clinical and endoscopic remission. Additional, preferably randomised, controlled studies are needed to characterise efficacy using objective markers of mucosal inflammation, and to examine safety and define optimal dosing.
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Antimicrobial susceptibility patterns of aerobic bacteria isolated from canine urinary samples in South East Queensland, 2013 to 2018. Aust Vet J 2024. [PMID: 38654674 DOI: 10.1111/avj.13333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 03/10/2024] [Accepted: 04/01/2024] [Indexed: 04/26/2024]
Abstract
Urinary tract infections are a common diagnosis in dogs presenting to veterinary practice. Veterinarians often treat suspected infections empirically, either in the absence of culture and susceptibility testing results or whilst waiting for them. This study aimed to identify the bacteria most frequently isolated from canine urinary samples and their antimicrobial susceptibility patterns in South East Queensland (SEQ) to help guide responsible empirical antimicrobial prescription by the veterinary community in this geographical location. Cumulative antibiograms were generated from the results of 1284 culture-positive urinary samples in SEQ, obtained from a commercial veterinary laboratory over a 5-year period. Escherichia coli was the most commonly isolated bacterial species (43%), followed by Staphylococcus spp. (23%), Proteus spp. (21%) and Enterococcus spp. (10%). Of the six most common isolates, 97% had susceptibility to at least one low-importance antimicrobial. Susceptibility to the low-importance and first-line antimicrobial recommendation, amoxicillin, was 81% for E. coli and 24% for Staphylococcus spp. Susceptibility of both E. coli and Staphylococcus spp. to medium-importance and commonly recommended empirical antimicrobials, trimethoprim sulphonamides and amoxicillin-clavulanic acid was ≥85% and >92% for high-importance antimicrobials enrofloxacin and ceftiofur. Of the E. coli and Staphylococcus spp. isolates, 8.8% and 4%, respectively, were considered multidrug resistant. There was no increase in resistance to antimicrobials detected over the study period. Susceptibilities suggest low- and medium-importance antimicrobials remain acceptable first-line empirical treatments. However, this should be continually assessed and updated using local surveillance data.
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Autoimmune hepatitis: Brighton Collaboration case definition and guidelines for data collection, analysis, and presentation of immunisation safety data. Vaccine 2024; 42:1812-1825. [PMID: 38368225 DOI: 10.1016/j.vaccine.2024.01.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 01/05/2024] [Indexed: 02/19/2024]
Abstract
This report introduces a Brighton Collaboration (BC) case definition for autoimmune hepatitis (AIH), which has been classified as a priority adverse event of special interest (AESI), as there were possible cases seen following COVID-19 vaccination. The case definition was developed by a group of subject matter and BC process experts to facilitate safety data comparability across pre- and post-licensure clinical trials, as well as pharmacovigilance activities in multiple settings with diverse resources and healthcare access. The usual BC case definition development process was followed in an expedited manner, and took two months to complete, including finalising the manuscript for publication, instead of the usual 1 year development time. It includes a systematic review of the literature and an expert consensus to define levels of diagnostic certainty for AIH, and provides specific guidelines for data collection and analysis. Histology, serological and biochemical tests and exclusion of alternate diagnosis were considered necessary to define the levels of certainty (definitive, probable and possible). AEFI reports of suspected AIH were independently classified by the WG members to test its useability and these classifications were used to finalise the case definition. The document underwent peer review by external AIH experts and a Reference Group of vaccine safety stakeholders in high-, low- and middle-income countries to ensure case definition useability, applicability, and scientific integrity. The expedited process can be replicated for development of other standardised case definitions for priority AESIs for endemics and epidemics. While applicable to cases reported following immunisation, the case definition is independent of lapsed time following vaccination and, as such, can also be used to determine background incidence for vaccinated and unvaccinated control groups in studies of causal association. While use of this case definition is also appropriate for the study of safety of other products including drugs, it is not meant to guide clinical case management.
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Does High-Intensity Exercise Cause Acute Liver Injury in Patients with Fontan Circulation? A Prospective Pilot Study. Pediatr Cardiol 2023:10.1007/s00246-023-03193-y. [PMID: 37219588 DOI: 10.1007/s00246-023-03193-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 05/15/2023] [Indexed: 05/24/2023]
Abstract
The Fontan procedure results in chronic hepatic congestion and Fontan-associated liver disease (FALD) characterized by progressive liver fibrosis and cirrhosis. Exercise is recommended in this population, but may accelerate the progression of FALD from abrupt elevations in central venous pressure. The aim of this study was to assess if acute liver injury occurs after high-intensity exercise in patients with Fontan physiology. Ten patients were enrolled. Nine had normal systolic ventricular function and one had an ejection fraction < 40%. During cardiopulmonary exercise testing, patients had near-infrared spectroscopy (NIRS) to measure oxygen saturation of multiple organs, including the liver, and underwent pre- and post-exercise testing with liver elastography, laboratory markers, and cytokines to assess liver injury. The hepatic and renal NIRS showed a statistically significant decrease in oxygenation during exercise, and the hepatic NIRS had the slowest recovery compared to renal, cerebral, and peripheral muscle NIRS. A clinically significant increase in shear wave velocity occurred after exercise testing only in the one patient with systolic dysfunction. There was a statistically significant, albeit trivial, increase in ALT and GGT after exercise. Fibrogenic cytokines traditionally associated with FALD did not increase significantly in our cohort; however, pro-inflammatory cytokines that predispose to fibrogenesis did significantly rise during exercise. Although patients with Fontan circulation demonstrated a significant reduction in hepatic tissue oxygenation based on NIRS saturations during exercise, there was no clinical evidence of acute increase in liver congestion or acute liver injury following high-intensity exercise.
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Serum biomarkers correlated with liver stiffness assessed in a multicenter study of pediatric cholestatic liver disease. Hepatology 2023; 77:530-545. [PMID: 36069569 PMCID: PMC10151059 DOI: 10.1002/hep.32777] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 07/26/2022] [Accepted: 08/03/2022] [Indexed: 01/28/2023]
Abstract
BACKGROUND AND AIMS Detailed investigation of the biological pathways leading to hepatic fibrosis and identification of liver fibrosis biomarkers may facilitate early interventions for pediatric cholestasis. APPROACH AND RESULTS A targeted enzyme-linked immunosorbent assay-based panel of nine biomarkers (lysyl oxidase, tissue inhibitor matrix metalloproteinase (MMP) 1, connective tissue growth factor [CTGF], IL-8, endoglin, periostin, Mac-2-binding protein, MMP-3, and MMP-7) was examined in children with biliary atresia (BA; n = 187), alpha-1 antitrypsin deficiency (A1AT; n = 78), and Alagille syndrome (ALGS; n = 65) and correlated with liver stiffness (LSM) and biochemical measures of liver disease. Median age and LSM were 9 years and 9.5 kPa. After adjusting for covariates, there were positive correlations among LSM and endoglin ( p = 0.04) and IL-8 ( p < 0.001) and MMP-7 ( p < 0.001) in participants with BA. The best prediction model for LSM in BA using clinical and lab measurements had an R2 = 0.437; adding IL-8 and MMP-7 improved R2 to 0.523 and 0.526 (both p < 0.0001). In participants with A1AT, CTGF and LSM were negatively correlated ( p = 0.004); adding CTGF to an LSM prediction model improved R2 from 0.524 to 0.577 ( p = 0.0033). Biomarkers did not correlate with LSM in ALGS. A significant number of biomarker/lab correlations were found in participants with BA but not those with A1AT or ALGS. CONCLUSIONS Endoglin, IL-8, and MMP-7 significantly correlate with increased LSM in children with BA, whereas CTGF inversely correlates with LSM in participants with A1AT; these biomarkers appear to enhance prediction of LSM beyond clinical tests. Future disease-specific investigations of change in these biomarkers over time and as predictors of clinical outcomes will be important.
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Risk of variceal hemorrhage and pretransplant mortality in children with biliary atresia. Hepatology 2022; 76:712-726. [PMID: 35271743 PMCID: PMC9378352 DOI: 10.1002/hep.32451] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 02/24/2022] [Accepted: 02/25/2022] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND AIMS The natural history of gastroesophageal variceal hemorrhage (VH) in biliary atresia (BA) is not well characterized. We analyzed risk factors, incidence, and outcomes of VH in a longitudinal multicenter study. APPROACH AND RESULTS Participants enrolled in either an incident (Prospective Database of Infants with Cholestasis [PROBE]) or prevalent (Biliary Atresia Study of Infants and Children [BASIC]) cohort of BA were included. Variceal hemorrhage (VH) was defined based on gastrointestinal bleeding in the presence of varices accompanied by endoscopic or nontransplant surgical intervention. Cumulative incidence of VH and transplant-free survival was compared based on features of portal hypertension (e.g., splenomegaly, thrombocytopenia) and clinical parameters at baseline in each cohort (PROBE: 1.5 to 4.5 months after hepatoportoenterostomy [HPE]; BASIC: at enrollment > 3 years of age). Analyses were conducted on 869 children with BA enrolled between June 2004 and December 2020 (521 in PROBE [262 (51%) with a functioning HPE] and 348 in BASIC). The overall incidence of first observed VH at 5 years was 9.4% (95% CI: 7.0-12.4) in PROBE and 8.0% (5.2-11.5) in BASIC. Features of portal hypertension, platelet count, total bilirubin, aspartate aminotransferase (AST), albumin, and AST-to-platelet ratio index at baseline were associated with an increased risk of subsequent VH in both cohorts. Transplant-free survival at 5 years was 45.1% (40.5-49.6) in PROBE and 79.2% (74.1-83.4) in BASIC. Two (2.5%) of 80 participants who had VH died, whereas 10 (12.5%) underwent transplant within 6 weeks of VH. CONCLUSIONS The low risk of VH and associated mortality in children with BA needs to be considered in decisions related to screening for varices and primary prophylaxis of VH.
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Impact of long-term administration of maralixibat on children with cholestasis secondary to Alagille syndrome. Hepatol Commun 2022; 6:1922-1933. [PMID: 35672955 PMCID: PMC9315125 DOI: 10.1002/hep4.1992] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 04/03/2022] [Indexed: 11/10/2022] Open
Abstract
There is growing interest in, but limited data about, intestinal bile acid transport inhibitors as treatment for cholestatic liver disease. The current analyses combine two similar randomized placebo-controlled trials with subsequent extension phases investigating the impact of maralixibat in children with severe cholestasis secondary to Alagille Syndrome (n = 57). The primary outcomes were measures of pruritus (ItchRO[Obs]) and clinician scratch scale (CSS), both increasing in severity from 0 to 4) and quality of life (QoL) (Parent PedsQL and Multidimensional Fatigue Scale module [MFS] scaled 0-100 with increased QoL) at week 48 of the extension phase relative to the baseline of the placebo-controlled trials (week 13). Secondary assessments included other clinical and biochemical parameters assessed in participants at week 72 or end of treatment (after week 48). At week 48, statistically and clinically significant least square mean (95% CI) improvements in pruritus and QoL were observed (ItchRO[Obs] -1.59 [-1.81, -1.36], CSS -1.36 [-1.67, -1.05], PedsQL +10.17 [4.48, 15.86], and multidimension fatigue [MFS] +13.97 [7.85, 20.08]). At week 48, serum bile acids, platelet count, and cholesterol decreased, whereas alanine aminotransferase (ALT) increased and total bilirubin (TB) and albumin were stable. Changes were durable at week 72 and end of treatment. There were no deaths; 2 participants underwent liver transplantation. Study drug was discontinued in 9 participants after treatment-emergent adverse events, 6 of which were events of increased ALT or TB. Conclusion: Maralixibat administration was associated with marked improvement in pruritus and QoL. Interpretation of these findings is complicated by the complex natural history of severe cholestasis in Alagille syndrome.
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Maralixibat for the treatment of PFIC: Long-term, IBAT inhibition in an open-label, Phase 2 study. Hepatol Commun 2022; 6:2379-2390. [PMID: 35507739 PMCID: PMC9426380 DOI: 10.1002/hep4.1980] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 04/13/2022] [Accepted: 04/16/2022] [Indexed: 01/13/2023] Open
Abstract
Children with progressive familial intrahepatic cholestasis, including bile salt export pump (BSEP) and familial intrahepatic cholestasis–associated protein 1 (FIC1) deficiencies, suffer debilitating cholestatic pruritus that adversely affects growth and quality of life (QoL). Reliance on surgical interventions, including liver transplantation, highlights the unmet therapeutic need. INDIGO was an open‐label, Phase 2, international, long‐term study to assess the efficacy and safety of maralixibat in children with FIC1 or BSEP deficiencies. Thirty‐three patients, ranging from 12 months to 18 years of age, were enrolled. Eight had FIC1 deficiency and 25 had BSEP deficiency. Of the latter, 6 had biallelic, protein truncating mutations (t)‐BSEP, and 19 had ≥ 1 nontruncating mutation (nt)‐BSEP. Patients received maralixibat 266 μg/kg orally, once daily, from baseline to Week 72, with twice‐daily dosing permitted from Week 72. Long‐term efficacy was determined at Week 240. Serum bile acid (sBA) response (reduction in sBAs of > 75% from baseline or concentrations <102.0 μmol/L) was achieved in 7 patients with nt‐BSEP, 6 during once‐daily dosing, and 1 after switching to twice‐daily dosing. sBA responders also demonstrated marked reductions in sBAs and pruritus, and increases in height, weight, and QoL. All sBA responders remained liver transplant–free after > 5 years. No patients with FIC1 deficiency or t‐BSEP deficiency met the sBA responder criteria during the study. Maralixibat was generally well‐tolerated throughout the study. Conclusion: Response to maralixibat was dependent on progressive familial intrahepatic cholestasis subtype, and 6 of 19 patients with nt‐BSEP experienced rapid and sustained reductions in sBA levels. The 7 responders survived with native liver and experienced clinically significant reductions in pruritus and meaningful improvements in growth and QoL. Maralixibat may represent a well‐tolerated alternative to surgical intervention.
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Standardized evaluation of the quality and persuasiveness of mobile health applications for diabetes management. Sci Rep 2022; 12:3639. [PMID: 35256661 PMCID: PMC8901695 DOI: 10.1038/s41598-022-07544-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 02/02/2022] [Indexed: 11/08/2022] Open
Abstract
This study evaluates diabetes self-management mobile health applications available from European app stores with respect to quality, concordance with recommended self-management tasks and implementation of persuasive system design principles. The European Play Store and Apple App Store were systematically searched and relevant apps were tested. Two raters independently assessed app quality using the Mobile Application Rating Scale and conducted a content analysis of provided persuasive system design principles and self-management tasks. A total of 2,269 mobile health applications were identified and 120 could be included in the evaluation. The overall quality was rated as moderate M = 3.20 (SD = 0.39, min = 2.31, max = 4.62), with shortcomings in the subcategories of engagement (M = 2.80, SD = 0.67) and information quality (M = 2.26, SD = 0.48). Scientific evidence is available for 8% of the apps. The reviewed apps implemented a median of three persuasive system design principles (range 0-15) and targeted a median of 4.5 (range 1-8) self-management tasks, however, with a lack of information about psychosocial coping strategies. Most available diabetes self-management apps lack a scientific evidence base. Persuasive system design features are underrepresented and may form a promising tool to improve app quality. Furthermore, the interaction of physical and behavioral health should be improved in existing diabetes self-management mobile health applications.
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Peripherally administered amylin inhibits stress-like behaviors and enhances cognitive performance. Physiol Behav 2022; 244:113668. [PMID: 34863999 DOI: 10.1016/j.physbeh.2021.113668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 11/29/2021] [Accepted: 11/30/2021] [Indexed: 11/28/2022]
Abstract
Amylin, a 37 amino acid peptide pancreatic hormone co-secreted with insulin, normalizes the altered eating patterns induced by chronic stress in the rat. Because these stress-induced changes are driven, in part, by brain corticotropin-releasing factor and corticosterone, and because alterations in the activity of these molecules and the stress system are commonly associated with neuropsychiatric diseases like anxiety, depression, and schizophrenia, we hypothesized that amylin might mitigate behavioral states associated with stress. Therefore, we tested the effects of rat amylin in rodent-based behavioral assays sensitive to neuropsychiatric drugs, including anxiolytic, antidepressant, antipsychotic, and cognitive enhancing drugs: stress-induced hyperthermia (SIH); marble burying; elevated plus maze (EPM)), forced swim test (FST), pre-pulse inhibition, and phencyclidine-induced locomotion. To assess the neural underpinnings of amylin's anxiolytic-like effects, we examined the effect of amylin on SIH after lesioning the area postrema (AP), which mediates amylin's metabolic effects. Amylin injection (IP, 0.1, 1.0, & 10 mg/kg) significantly (P < 0.05) decreased SIH (97% below vehicle) and AP lesions inhibited this effect. Amylin also reduced marble burying (72% below vehicle), but had no effect in the EPM. Together, these effects suggest anxiolytic-like activity or potential. Amylin injection also enhanced cognitive performance in the novel object recognition test. When administered continuously by implanted osmotic pumps, amylin (300 mg/kg/d) blocked SIH when tested at 1 and 4 weeks. Compared to vehicle, amylin infusion (1 and 3 mg/kg/d) reduced the time immobile in the FST (P < 0.05; 30% below vehicle), suggesting antidepressant-like potential. Although further testing is needed, our findings support a potential for peripherally administered amylin to access and benefit pathways that regulate memory, emotion, and mood.
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Cholangitis Definition and Treatment after Kasai Hepatoportoenterostomy for Biliary Atresia: A Delphi Process and International Expert Panel. J Clin Med 2022; 11:jcm11030494. [PMID: 35159946 PMCID: PMC8836553 DOI: 10.3390/jcm11030494] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 01/14/2022] [Indexed: 12/17/2022] Open
Abstract
(1) Background: Acute cholangitis during the first year after Kasai hepatoportoenterostomy (HPE) has a negative impact on patient and native liver survival. There are no consistent guidelines for the definition, treatment, and prophylaxis of cholangitis after HPE. The aim of this study was to develop definition, treatment, and prophylaxis guidelines to allow for expeditious management and for standardization in reporting. (2) Methods: the Delphi method, an extensive literature review, iterative rounds of surveys, and expert panel discussions were used to establish definition, treatment, and prophylaxis guidelines for cholangitis in the first year after HPE. (3) Results: Eight elements (pooled into two groups: clinical and laboratory/imaging) were identified to define cholangitis after HPE. The final proposed definitions for suspected and confirmed cholangitis are a combination of one element, respectively, two elements from each group; furthermore, the finding of a positive blood culture was added to the definition of confirmed cholangitis. The durations for prophylaxis and treatment of suspected and confirmed cholangitis were uniformly agreed upon by the experts. (4) Conclusions: for the first time, an international consensus was found for guidelines for definition, treatment, and prophylaxis for cholangitis during the first year after Kasai HPE. Applicability will need further prospective multicentered studies.
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Severe Seronegative Hepatitis-associated Aplastic Anemia: Looking for the Best Treatment. J Pediatr Gastroenterol Nutr 2021; 73:e48. [PMID: 34016886 PMCID: PMC8373680 DOI: 10.1097/mpg.0000000000003166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
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The Sclerosing Cholangitis Outcomes in Pediatrics (SCOPE) Index: A Prognostic Tool for Children. Hepatology 2021; 73:1074-1087. [PMID: 32464706 PMCID: PMC8557635 DOI: 10.1002/hep.31393] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 04/21/2020] [Accepted: 05/03/2020] [Indexed: 12/16/2022]
Abstract
BACKGROUND AND AIMS Disease progression in children with primary sclerosing cholangitis (PSC) is variable. Prognostic and risk-stratification tools exist for adult-onset PSC, but not for children. We aimed to create a tool that accounts for the biochemical and phenotypic features and early disease stage of pediatric PSC. APPROACH AND RESULTS We used retrospective data from the Pediatric PSC Consortium. The training cohort contained 1,012 patients from 40 centers. We generated a multivariate risk index (Sclerosing Cholangitis Outcomes in Pediatrics [SCOPE] index) that contained total bilirubin, albumin, platelet count, gamma glutamyltransferase, and cholangiography to predict a primary outcome of liver transplantation or death (TD) and a broader secondary outcome that included portal hypertensive, biliary, and cancer complications termed hepatobiliary complications (HBCs). The model stratified patients as low, medium, or high risk based on progression to TD at rates of <1%, 3%, and 9% annually and to HBCs at rates of 2%, 6%, and 13% annually, respectively (P < 0.001). C-statistics to discriminate outcomes at 1 and 5 years were 0.95 and 0.82 for TD and 0.80 and 0.76 for HBCs, respectively. Baseline hepatic fibrosis stage was worse with increasing risk score, with extensive fibrosis in 8% of the lowest versus 100% with the highest risk index (P < 0.001). The model was validated in 240 children from 11 additional centers and performed well. CONCLUSIONS The SCOPE index is a pediatric-specific prognostic tool for PSC. It uses routinely obtained, objective data to predict a complicated clinical course. It correlates strongly with biopsy-proven liver fibrosis. SCOPE can be used with families for shared decision making on clinical care based on a patient's individual risk, and to account for variable disease progression when designing future clinical trials.
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Oral Vancomycin, Ursodeoxycholic Acid, or No Therapy for Pediatric Primary Sclerosing Cholangitis: A Matched Analysis. Hepatology 2021; 73:1061-1073. [PMID: 32946600 PMCID: PMC8557636 DOI: 10.1002/hep.31560] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 08/21/2020] [Accepted: 08/27/2020] [Indexed: 02/06/2023]
Abstract
BACKGROUND AND AIMS Many children with primary sclerosing cholangitis (PSC) receive oral vancomycin therapy (OVT) or ursodeoxycholic acid (UDCA). There is a paucity of data on whether these medications improve outcomes. APPROACH AND RESULTS We analyzed retrospective data from the Pediatric PSC Consortium. Children treated with OVT were matched 1:1:1 to those treated with UDCA or managed with observation (no treatment) based on the closest propensity score, ensuring similar baseline characteristics. Two hundred sixty-four patients (88 each with OVT, UDCA, or observation) had matching propensity scores and were similar in demographics, phenotype, immunosuppression, baseline biochemistry, and hepatic fibrosis. After 1 year in an intention-to-treat analysis, all outcome metrics were similar regardless of treatment group. In OVT, UDCA, and untreated groups, respectively: Gamma-glutamyltransferase normalized in 53%, 49%, and 52% (P = not significant [NS]), liver fibrosis stage was improved in 20%, 13%, and 18% and worsened in 11%, 29%, and 18% (P = NS), and the 5-year probability of liver transplant listing was 21%, 10%, and 12% (P = NS). Favorable outcome was associated with having a mild phenotype of PSC and minimal hepatic fibrosis. CONCLUSIONS We presented the largest-ever description of outcomes on OVT in PSC and compared them to carefully matched patients on UDCA or no therapy. Neither OVT nor UDCA showed improvement in outcomes compared to a strategy of observation. Patients progressed to end-stage liver disease at similar rates. Spontaneous normalization of biochemistry is common in children receiving no therapy, particularly in the majority of children with a mild phenotype and an early stage of disease. Placebo-controlled treatment trials are needed to identify effective treatments for pediatric PSC.
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Abstract
OBJECTIVES Hepatitis-associated aplastic anemia (HAAA) is a potentially life-threatening diagnosis without clear treatment guidelines. The goal of the study was to characterize the presentation, evaluation, histopathology, and outcomes of therapy in children with HAAA to guide future research and to develop standardized care guidelines for this rare disease. METHODS Retrospective chart review of 4 patients with HAAA who presented to Children's Hospital Colorado between 2016 and 2019 was conducted. Patient presentation, evaluation, bone marrow and liver pathology, interventions, and clinical course were collected. Immunohistochemistry of liver biopsies was performed. RESULTS We treated 4 patients with HAAA without liver failure. All had evidence of systemic hyperinflammation and CD8+ T cell predominant liver tissue infiltration. One had a genetic mutation predisposing him to immune-mediated disease, but all other genetic testing was negative. In 3 of the 4 patients, hepatitis was poorly responsive to standard therapy with steroids, azathioprine, or tacrolimus; however, sustained biochemical remission of hepatitis was induced after more aggressive immunosuppressive therapies including Anti-Thymocyte Globulin (ATG) at standard immunosuppressive therapy (IST) dosing for severe Aplastic Anemia (sAA). Two patients underwent hematopoietic stem cell transplant (HSCT); 1 as first line therapy and 1 for refractory sAA. CONCLUSIONS We found that ATG-based IST induced remission of hepatitis in patients with steroid-refractory HAAA. This is also an appropriate initial treatment for severe Aplastic Anemia, though may not prevent the need for HSCT. We propose that equine ATG based IST at standard dosing regimen for sAA is a therapy that in select cases can be considered early on in the treatment course and could lead to a sustained remission of both hepatitis and sAA. This should be considered in collaboration with a pediatric hematologist.
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Ileal bile acid transporter inhibition as an anticholestatic therapeutic target in biliary atresia and other cholestatic disorders. Hepatol Int 2020; 14:677-689. [PMID: 32653991 DOI: 10.1007/s12072-020-10070-w] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 06/22/2020] [Indexed: 12/20/2022]
Abstract
Biliary atresia is a rare cholestatic liver disease that presents in infants and rapidly advances to death in the absence of intervention. As a result of blockage or destruction of the biliary tract, bile acids accumulate and drive inflammation, fibrosis, and disease progression. The standard of care, Kasai portoenterostomy (KPE), is typically performed shortly after diagnosis (currently at ~ 2 months of age) and aims to restore bile flow and relieve cholestasis. Nevertheless, most patients continue to experience liver injury from accumulation of bile acids after KPE, since there are no known effective therapeutics that may enhance survival after KPE. Improving cholestasis via interruption of the enterohepatic circulation of bile acids may directly attenuate hepatic bile acid retention and reduce the risk of early organ failure. Directly addressing intrahepatic accretion of bile acids to avoid inherent bile acid toxicities provides an attractive and plausible therapeutic target for biliary atresia. This review explores the novel therapeutic concept of inhibiting the sole ileal bile acid transporter (IBAT), also known as ASBT (apical sodium-bile acid transporter, encoded by SLC10A2), as a means to reduce hepatic bile acid concentration after KPE. By reducing return of bile acids to the cholestatic liver, IBAT inhibitors may potentially lessen or delay liver damage associated with the hepatotoxicity and cholangiopathy of bile acid accumulation. The clinical programs of 2 IBAT inhibitors in development for the treatment of pediatric cholestatic liver diseases, maralixibat and odevixibat, are highlighted.
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A Prospective Trial of Withdrawal and Reinstitution of Ursodeoxycholic Acid in Pediatric Primary Sclerosing Cholangitis. Hepatol Commun 2019; 3:1482-1495. [PMID: 31701072 PMCID: PMC6824074 DOI: 10.1002/hep4.1421] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 07/27/2019] [Indexed: 12/15/2022] Open
Abstract
Ursodeoxycholic acid (UDCA) is commonly used to treat several liver disorders in adults and children, including primary sclerosing cholangitis (PSC) for which it is not U.S. Food and Drug Administration approved. UDCA treatment has an uncertain impact on disease outcomes and has been reported in high doses to be associated with worse outcome in adults with PSC. In this context, controlled withdrawal and reintroduction of UDCA in children with PSC were studied. Prior to study initiation, participants were required to have alanine aminotransferase (ALT) and gamma‐glutamyl transpeptidase (GGT) <2 times the upper limit of normal on stable UDCA dosing. The study included four phases: I (stable dosing), II (50% UDCA reduction), III (UDCA discontinuation), IV (UDCA reintroduction), with a primary endpoint of change in ALT and GGT between phases I and III. We enrolled 27 participants (22 completed) between March 2011 and June 2016. Changes in mean ALT and GGT between phases I and III were ALT, +29.5 IU/L (P = 0.105) and GGT, +60.4 IU/L (P = 0.003). In 7 participants, ALT and GGT ≤29 IU/L did not rise above 29 IU/L (null response group). Eight participants had increases of ALT or GGT >100 IU/L (flare group). None developed elevated bilirubin. All flares responded to UDCA reinstitution. Serum GGT, interleukin‐8, and tumor necrosis factor α levels were higher in the flare group at baseline. Liver biochemistries increased in children with PSC during controlled UDCA withdrawal; one third increased above 100 IU/L and one third remained normal during UDCA withdrawal. Conclusion: The impact of prolonged UDCA use in childhood PSC and the significance of a biochemical flare are unclear. Further studies of the natural history and treatment of pediatric PSC and UDCA use are needed.
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From Hepatocyte to Cholangiocyte: The Remarkable Potential of Transdifferentiation to Treat Cholestatic Diseases. Hepatology 2019; 69:1828-1830. [PMID: 30179266 DOI: 10.1002/hep.30250] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Gamma Glutamyltransferase Reduction Is Associated With Favorable Outcomes in Pediatric Primary Sclerosing Cholangitis. Hepatol Commun 2018; 2:1369-1378. [PMID: 30411083 PMCID: PMC6211333 DOI: 10.1002/hep4.1251] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 07/13/2018] [Indexed: 12/15/2022] Open
Abstract
Adverse clinical events in primary sclerosing cholangitis (PSC) happen too slowly to capture during clinical trials. Surrogate endpoints are needed, but no such validated endpoints exist for children with PSC. We evaluated the association between gamma glutamyltransferase (GGT) reduction and long-term outcomes in pediatric PSC patients. We evaluated GGT normalization (< 50 IU/L) at 1 year among a multicenter cohort of children with PSC who did or did not receive treatment with ursodeoxycholic acid (UDCA). We compared rates of event-free survival (no portal hypertensive or biliary complications, cholangiocarcinoma, liver transplantation, or liver-related death) at 5 years. Of the 287 children, mean age of 11.4 years old, UDCA was used in 81% at a mean dose of 17 mg/kg/day. Treated and untreated groups had similar GGT at diagnosis (314 versus 300, P= not significant [NS]). The mean GGT was reduced at 1 year in both groups, with lower values seen in treated (versus untreated) patients (99 versus 175, P= 0.002), but 5-year event-free survival was similar (74% versus 77%, P= NS). In patients with GGT normalization (versus no normalization) by 1 year, regardless of UDCA treatment status, 5-year event-free survival was better (91% versus 67%, P< 0.001). Similarly, larger reduction in GGT over 1 year (> 75% versus < 25% reduction) was also associated with improved outcome (5-year event-free survival 88% versus 61%, P= 0.005). Conclusion:A GGT < 50 and/or GGT reduction of > 75% by 1 year after PSC diagnosis predicts favorable 5-year outcomes in children. GGT has promise as a potential surrogate endpoint in future clinical trials for pediatric PSC.
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Metabolite profiles evaluated, according to sex, do not predict resting energy expenditure and lean body mass in healthy non-obese subjects. Eur J Nutr 2018; 58:2207-2217. [PMID: 29974226 PMCID: PMC6689277 DOI: 10.1007/s00394-018-1767-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 06/29/2018] [Indexed: 12/16/2022]
Abstract
PURPOSE Differences in resting energy expenditure (REE) between men and women mainly result from sex-related differences in lean body mass (LBM). So far, a little is known about whether REE and LBM are reflected by a distinct human metabolite profile. Therefore, we aimed to identify plasma and urine metabolite patterns that are associated with REE and LBM of healthy subjects. METHODS We investigated 301 healthy male and female subjects (18-80 years) under standardized conditions in the cross-sectional KarMeN (Karlsruhe Metabolomics and Nutrition) study. REE was determined by indirect calorimetry and LBM by dual X-ray absorptiometry. Fasting blood and 24 h urine samples were analyzed by targeted and non-targeted metabolomics methods using GC × GC-MS, GC-MS, LC-MS, and NMR. Data were evaluated by predictive modeling of combined data using different machine learning algorithms, namely SVM, glmnet, and PLS. RESULTS When evaluating data of men and women combined, we were able to predict REE and LBM with high accuracy (> 90%). This, however, was a clear effect of sex, which is supported by the high degree of overlap in identified important metabolites for LBM, REE, and sex, respectively. The applied machine learning algorithms did not reveal a metabolite pattern predictive of REE or LBM, when analyzing data for men and women, separately. CONCLUSIONS We could not identify a sex independent predictive metabolite pattern for REE or LBM. REE and LBM have no impact on plasma and urine metabolite profiles in the KarMeN Study participants. Studies applying metabolomics in healthy humans need to consider sex specific data evaluation.
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The natural history of primary sclerosing cholangitis in 781 children: A multicenter, international collaboration. Hepatology 2017; 66:518-527. [PMID: 28390159 DOI: 10.1002/hep.29204] [Citation(s) in RCA: 126] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 02/07/2017] [Accepted: 04/04/2017] [Indexed: 12/14/2022]
Abstract
UNLABELLED There are limited data on the natural history of primary sclerosing cholangitis (PSC) in children. We aimed to describe the disease characteristics and long-term outcomes of pediatric PSC. We retrospectively collected all pediatric PSC cases from 36 participating institutions and conducted a survival analysis from the date of PSC diagnosis to dates of diagnosis of portal hypertensive or biliary complications, cholangiocarcinoma, liver transplantation, or death. We analyzed patients grouped by disease phenotype and laboratory studies at diagnosis to identify objective predictors of long-term outcome. We identified 781 patients, median age 12 years, with 4,277 person-years of follow-up; 33% with autoimmune hepatitis, 76% with inflammatory bowel disease, and 13% with small duct PSC. Portal hypertensive and biliary complications developed in 38% and 25%, respectively, after 10 years of disease. Once these complications developed, median survival with native liver was 2.8 and 3.5 years, respectively. Cholangiocarcinoma occurred in 1%. Overall event-free survival was 70% at 5 years and 53% at 10 years. Patient groups with the most elevated total bilirubin, gamma-glutamyltransferase, and aspartate aminotransferase-to-platelet ratio index at diagnosis had the worst outcomes. In multivariate analysis PSC-inflammatory bowel disease and small duct phenotypes were associated with favorable prognosis (hazard ratios 0.6, 95% confidence interval 0.5-0.9, and 0.7, 95% confidence interval 0.5-0.96, respectively). Age, gender, and autoimmune hepatitis overlap did not impact long-term outcome. CONCLUSION PSC has a chronic, progressive course in children, and nearly half of patients develop an adverse liver outcome after 10 years of disease; elevations in bilirubin, gamma-glutamyltransferase, and aspartate aminotransferase-to-platelet ratio index at diagnosis can identify patients at highest risk; small duct PSC and PSC-inflammatory bowel disease are more favorable disease phenotypes. (Hepatology 2017;66:518-527).
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Analysis of surgical interruption of the enterohepatic circulation as a treatment for pediatric cholestasis. Hepatology 2017; 65:1645-1654. [PMID: 28027587 PMCID: PMC5397365 DOI: 10.1002/hep.29019] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 11/21/2016] [Accepted: 12/20/2016] [Indexed: 12/12/2022]
Abstract
UNLABELLED To evaluate the efficacy of nontransplant surgery for pediatric cholestasis, 58 clinically diagnosed children, including 20 with Alagille syndrome (ALGS), 16 with familial intrahepatic cholestasis-1 (FIC1), 18 with bile salt export pump (BSEP) disease, and 4 others with low γ-glutamyl transpeptidase disease (levels <100 U/L), were identified across 14 Childhood Liver Disease Research Network (ChiLDReN) centers. Data were collected retrospectively from individuals who collectively had 39 partial external biliary diversions (PEBDs), 11 ileal exclusions (IEs), and seven gallbladder-to-colon (GBC) diversions. Serum total bilirubin decreased after PEBD in FIC1 (8.1 ± 4.0 vs. 2.9 ± 4.1 mg/dL, preoperatively vs. 12-24 months postoperatively, respectively; P = 0.02), but not in ALGS or BSEP. Total serum cholesterol decreased after PEBD in ALGS patients (695 ± 465 vs. 457 ± 319 mg/dL, preoperatively vs. 12-24 months postoperatively, respectively; P = 0.0001). Alanine aminotransferase levels increased in ALGS after PEBD (182 ± 70 vs. 260 ± 73 IU/L, preoperatively vs. 24 months; P = 0.03), but not in FIC1 or BSEP. ALGS, FIC1, and BSEP patients experienced less severely scored pruritus after PEBD (ALGS, 100% vs. 9% severe; FIC1, 64% vs. 10%; BSEP, 50% vs. 20%, preoperatively vs. >24 months postoperatively, respectively; P < 0.001). ALGS patients experienced a trend toward greater freedom from xanthomata after PEBD. There was a trend toward decreased pruritus in FIC1 after IE and GBC. Vitamin K supplementation increased in ALGS after PEBD (33% vs. 77%; P = 0.03). Overall, there were 15 major complications after surgery. Twelve patients (3 ALGS, 3 FIC1, and 6 BSEP) subsequently underwent liver transplantation. CONCLUSION This was a multicenter analysis of nontransplant surgical approaches to intrahepatic cholestasis. Approaches vary, are well tolerated, and generally, although not uniformly, result in improvement of pruritus and cholestasis. (Hepatology 2017;65:1645-1654).
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RLS around the globe: Diagnosis and epidemiology. Sleep Med 2013. [DOI: 10.1016/j.sleep.2013.11.644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Twin-screw extrusion of multi walled carbon nanotubes reinforced polycarbonate composites: Investigation of electrical and mechanical properties. ACTA ACUST UNITED AC 2012. [DOI: 10.1088/1757-899x/40/1/012020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
A variety of anatomic, infectious, autoimmune, and metabolic diseases can lead to conjugated hyperbilirubinemia, both in the newborn period and later in childhood. The pediatric practitioner is most likely to encounter conjugated hyperbilirubinemia in the neonatal period.It is crucial to maintain a high degree of suspicion for cholestasis in the persistently jaundiced newborn. The goal is recognition of conjugated hyperbilirubinemia between 2 and 4 weeks after birth, allowing for the prompt identification and management of infants who have biliary atresia, which remains the most common cause of neonatal cholestasis.
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Impaired bone microenvironment: correlation between bone density and presence of disseminated tumor cells. Anticancer Res 2011; 31:4423-4428. [PMID: 22199310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
BACKGROUND Disseminated tumor cells (DTCs) in bone marrow (BM) occur in 30-40% of primary breast cancer patients. An impaired bone microenvironment may lead to reduced bone density and osteoporosis affecting the BM as a homing site for DTCs. The bone mineral density (BMD) and its correlation to DTC in BM was evaluated. MATERIALS AND METHODS One hundred and eighty-one women (70 premenopausal, 111 postmenopausal) underwent quantitative ultrasonometry before adjuvant chemotherapy. BM aspirates were analyzed by immunocytochemistry using the ACIS system (Chromavision) based on immunostaining. RESULTS DTCs were detected in 39% of the patients. Positive BM status correlated significantly with the nodal status. BMD was significantly reduced in the postmenopausal patients (p=0.003). Smaller tumors and higher BMD correlated significantly (p<0.014). Fifty percent of the patients with preclinical osteoporosis were BM positive, whereas 37% with normal or osteopenic BMD had DTCs. CONCLUSION An impaired bone micro-environment as found in preclinical osteoporosis might be a homing site for DTCs.
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Regulatory T cell perturbation in biliary atresia (115.4). THE JOURNAL OF IMMUNOLOGY 2011. [DOI: 10.4049/jimmunol.186.supp.115.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Biliary atresia (BA) is an inflammatory disease of the biliary system which leads to cirrhosis and the need for liver transplantation in the majority of children. The etiology of BA is unknown and one theory is that bile duct injury is due to a virus-induced, subsequent autoreactive T cell-mediated inflammatory insult. Perturbation of the quantity or function of regulatory T cells (Tregs) in BA could result in unchecked autoimmunity. The aim of this study is to determine if Tregs are diminished or dysfunctional in murine and human BA. Murine BA results from infection of BALB/c neonates with Rhesus rotavirus (RRV). Mice infected with RRV on day 1 that received either Tregs or control T cells on day 5 led to a difference in disease status as early as 4 days post-transfer. This trend continued and biliary disease occurred in 67% of controls vs. 39% of Tregs recipients at 17 days of life. Secondly, ablation of functional Tregs in 4 day-old mice by treatment with a CD25-depleting antibody followed by RRV infection 3 days later results in increased bile duct infiltrate and disease incidence at 3 weeks of age. Finally, analysis of human PBMCs revealed a decreased percentage of FoxP3+ Tregs in BA patients (1.5±0.3%) compared to age-matched controls (4.1±0.7%). These studies suggest that lack of or dysregulation of Tregs is present in the murine model of BA and that diminished numbers of Tregs may be implicated in human BA progression.
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Do early stages of lumbar intervertebral disc degeneration really cause instability? Evaluation of an in vitro database. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2010; 20:578-84. [PMID: 21125299 DOI: 10.1007/s00586-010-1635-z] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 09/18/2010] [Accepted: 11/14/2010] [Indexed: 11/29/2022]
Abstract
Early stages of intervertebral disc degeneration are postulated to cause instability. In the literature, however, some authors report the opposite. These contradictory positions are probably supported by the mostly small number of segments which are investigated. The aim of this project therefore was to investigate the influence of intervertebral disc degeneration on lumbar spine rotational stability using a large data set. The flexibility data from all spine specimens tested in our institute so far were collected in a large in vitro database. From this database, all lumbar spine specimens were selected, which had been tested for flexibility under pure moment loads of ±7.5 N m and for which radiographs were accessible. 203 segments met these criteria. Their radiographic degree of disc degeneration was determined on a scale from 0 (no degeneration) to 3 (severe degeneration) and their influence on the respective range of motion and neutral zone was examined. The different lumbar levels differ in flexibility, which increases the variability of the data if pooled together. To minimise this effect a statistical model was fitted. The model-based mean estimates showed a decrease of the range of motion from grade 0 to 3 in flexion/extension (by 3.1°, p < 0.05) and lateral bending (by 3.4°, p < 0.05). In contrast, in axial rotation the range of motion tended to increase; however, not only from grade 0 to 1 but also towards grade 3 (by 0.2°) (p > 0.05). The neutral zone was affected in a similar way but to a smaller degree (p > 0.05). In conclusion, the results indicated that early stages of intervertebral disc degeneration do not necessarily cause rotational instability. In contrast, stability increased in flexion/extension and lateral bending. Only in axial rotation stability tended to decrease.
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XC. An exact formula for Qk(n), the probable number of k-aggregates in a random distribution of n points. ACTA ACUST UNITED AC 2010. [DOI: 10.1080/14786444808521801] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Abstract
Interspinous spacers are commonly used to treat lumbar spinal stenosis or facet joint arthritis. The aims of implanting interspinous devices are to unload the facet joints, restore foraminal height, and provide stability especially in extension but still allow motion. This paper summarizes several in vitro studies, which compared four different interspinous implants - Coflex, Wallis, DIAM, and X-STOP - in terms of their three-dimensional primary stability, the intradiscal pressure, and stability after cyclic loading. 24 human lumbar spine specimens were divided into four equal groups and tested with pure moments in flexion/extension, lateral bending, and axial rotation: intact, after decompression with hemifacetectomy, and after implantation. Implantation had similar biomechanical effects with all four implants. In extension, they overcompensated the instability caused by the defect and restricted extension to about 50% compared to the intact state. In contrast, in flexion, lateral bending, and axial rotation the values of the range of motion stayed similar compared to the defective state. Intradiscal pressure after implantation was similar to that of the intact specimens in flexion, lateral bending, and axial rotation but much smaller during extension; 50,000 load cycles increased the range of motion in all motion planes by no more than 20%, but in extension motion this was still less than in the intact state.
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Metal–biomass interactions: a comparison of visualisation techniques available in South Africa. S AFR J SCI 2010. [DOI: 10.4102/sajs.v105i3/4.61] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Biomechanical effect of different lumbar interspinous implants on flexibility and intradiscal pressure. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2008; 17:1049-56. [PMID: 18584219 DOI: 10.1007/s00586-008-0657-2] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2007] [Revised: 01/17/2008] [Accepted: 03/11/2008] [Indexed: 10/21/2022]
Abstract
Interspinous implants are used to treat lumbar spinal stenosis or facet joint arthritis. The aims of implanting interspinous devices are to unload the facet joints, restore foraminal height and provide stability especially in extension but still allow motion. The aim of this in vitro study was to compare four different interspinous implants--Colfex, Wallis, Diam and X-Stop--in terms of their three-dimensional flexibility and the intradiscal pressure. Twenty-four human lumbar spine specimens were divided into four equal groups and tested with pure moments in flexion/extension, lateral bending and axial rotation: (1) intact, (2) defect, (3) after implantation. Range of motion and the intradiscal pressure were determined. In each implant-group the defect caused an increase in range of motion by about 8% in lateral bending to 18% in axial rotation. Implantation had similar effects with all four implants. In extension, Coflex, Wallis, Diam, and X-Stop all overcompensated the instability caused by the defect and allowed about 50% of the range of motion of the intact state. In contrast, in flexion, lateral bending and axial rotation the values of the range of motion stayed about the values of the defect state. Similarly the intradiscal pressure after implantation was similar to that of the intact specimens in flexion, lateral bending and axial rotation but much smaller during extension. All tested interspinous implants had a similar effect on the flexibility: they strongly stabilized and reduced the intradiscal pressure in extension, but had almost no effect in flexion, lateral bending and axial rotation.
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Antiobesity effects of the beta-cell hormone amylin in combination with phentermine or sibutramine in diet-induced obese rats. Int J Obes (Lond) 2008; 32:1201-10. [PMID: 18560368 DOI: 10.1038/ijo.2008.91] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVE To characterize the interactive effects of amylin with phentermine or sibutramine on food intake, body weight/composition and gene expression in diet-induced obese (DIO) rats. DESIGN DIO rats were intraperitoneally injected with a single dose of amylin (10 microg kg(-1)) and/or phentermine (1 mg kg(-1)) or chronically infused with amylin (100 microg kg(-1) d(-1)) or vehicle with or without phentermine (0.5-10 mg kg(-1) d(-1)) or sibutramine (3 mg kg(-1) d(-1)) using two surgically implanted subcutaneous osmotic mini-pumps. MEASUREMENTS Twenty-four hour food intake, locomotor activity and components of meal microstructure (meal size, latency, duration and intermeal interval) were measured following acute administration (amylin, phentermine or amylin+phentermine). Body weight and composition (for amylin and/or sibutramine or phentermine) and metabolism-related gene mRNA expression in the liver (fatty acid synthase, stearoyl-CoA desaturase-1 and carnitine palmitoyltransferase-1) and brown fat (beta-adrenergic receptors and uncoupling protein-1) were measured (for amylin and/or phentermine) after sustained infusion (2 weeks). RESULTS Acute co-administration of amylin (10 microg kg(-1)) and phentermine (1 mg kg(-1)) reduced acute food intake (up to 19 h) more than either monotherapy. In two studies, sustained subcutaneous infusion of amylin for 2 weeks decreased cumulative food intake (22%) and vehicle-corrected body weight gain ( approximately 4-8%). Phentermine's anorexigenic (10-17%) and weight-reducing effects ( approximately 0-5%) were only evident at the highest dose tested (10 mg kg(-1) d(-1)). Combination of amylin (100 microg kg(-1) d(-1)) and phentermine reduced food intake (30-43%), body weight (8-12%) and adiposity to a greater extent than either monotherapy. Amylin prevented phentermine-induced reductions in UCP-1 mRNA in brown adipose tissue. When amylin+sibutramine were infused, mathematically additive decreases in food intake (up to 45%) and body weight (up to 12%) were evident. Similar to amylin+phentermine treatment, amylin+sibutramine mediated weight loss was attributable to significant reductions in fat mass. CONCLUSIONS Combined treatment of DIO rats with the pancreatic beta-cell hormone amylin and phentermine or sibutramine resulted in additive anorexigenic, weight- and fat-reducing effects.
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Can a modified interspinous spacer prevent instability in axial rotation and lateral bending? A biomechanical in vitro study resulting in a new idea. Clin Biomech (Bristol, Avon) 2008; 23:242-7. [PMID: 17981380 DOI: 10.1016/j.clinbiomech.2007.09.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2007] [Revised: 09/04/2007] [Accepted: 09/06/2007] [Indexed: 02/07/2023]
Abstract
BACKGROUND Interspinous spacers are mainly used to treat lumbar spinal stenosis and facet arthrosis. Biomechanically, they stabilise in extension but do not compensate instability in axial rotation and lateral bending. It would therefore be desirable to have an interspinous spacer available, which provides for more stability also in these two planes. At the same time, the intervertebral disc should not completely be unloaded to keep it viable. To meet these requirements, a new version of the Coflex interspinous implant was developed, called "Coflex rivet", which can be more rigidly attached to the spinous processes. The aim was to investigate whether this new implant compensates instability but still allows some load to be transferred through the disc. METHODS Twelve human lumbar spine segments were equally divided into two groups, one for Coflex rivet and one for the original Coflex implant. The specimens were tested for flexibility under pure moment loads in the three main planes. These tests were carried out in the intact condition, after creation of a destabilising defect and after insertion of either of the two implants. Before implantation, the interspinous spacers were equipped with strain gauges to measure the load transfer. FINDINGS Compared to the defect condition, both implants had a strong stabilising effect in extension (P<0.05). Coflex rivet also strongly stabilised in flexion and to a smaller degree in lateral bending and axial rotation (P<0.05). In contrast, in these three loading directions, the original Coflex implant could not compensate the destabilising effect of the defect (P>0.05). The bending moments transferred through the implants were highest in extension and flexion. Yet, they were no more than 1.2 Nm in median. INTERPRETATION The new Coflex rivet seems be a suitable option to compensate instability. Its biomechanical characteristics might even make it suitable as an adjunct to fusion, which would be a new indication for this type of implant.
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Combination therapy with amylin and PYY(3–36) in diet-induced obese rats: A response surface analysis. Appetite 2007. [DOI: 10.1016/j.appet.2007.03.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Abstract
Biosorption has emerged as a low-cost and often low-tech option for removal or recovery of base metals from aqueous wastes. The conditions under which precious metals such as gold, platinum and palladium are sorbed by biomass are often very different to those under which base metals are sorbed. This, coupled with the increasingly high demand for precious metals, drives the increase in research into efficient recovery of precious metal ions from all waste material, especially refining wastewaters. Common biosorbents for precious metal ions include various derivatives of chitosan, as well as other compounds with relatively high surface amine functional group content. This is generally due to the ability of the positively charged amine groups to attract anionic precious metal ions at low pH. Recent research regarding the biosorption of some precious metals is reviewed here, with emphasis on the effects of the biosorption environment and the biosorption mechanisms identified.
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Generation of T-cell Hybridomas Specific for Bile Duct and Rhesus Rotavirus Antigens in a Murine Model of Biliary Atresia (130.27). THE JOURNAL OF IMMUNOLOGY 2007. [DOI: 10.4049/jimmunol.178.supp.130.27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Abstract
Rhesus rotavirus (RRV)-inoculated neonatal BALB/c mice develop an immune mediated inflamation of both extra- and intraheptatic bile ducts which progresses to biliary obstruction and death by 3 weeks of age. The livers of diseased animals demonstrate increased numbers of T-lymphocytes along with elevated expression of Th1 type cytokines at both one and two weeks. Previous work in our laboratory has demonstrated that the liver infiltrating T-lymphocytes are both RRV-reactive and autoreactive to bile duct antigens. In addition, transfer of T-cells from diseased animals leads to inflamation of bile ducts in SCID mice. This inflamation occurs in the absence of virus, suggesting that bile duct antigens alone are capable of soliciting this response. In order to identify the antigens being targeted, and to determine if the autoreactivity arises via an epitope spreading or molecular mimicry mechanism, we have generated T-cell hybridomas from the livers of 2 week old diseased mice. Initial analysis of these hybridomas reveals four classes of hybridomas.
TCR positive but non-reactive to tested antigens,RRV-specific,bile duct-specific, anddual reactive to both RRV and bile duct antigens.
Further study of these hybridomas should clarify what mechanism is occuring and assist in identification of autoantigens.
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O0050 Restless legs syndrome patients: International Restless Legs Scale scores, serum ferritin levels and Suggested Immobilization Test results. Sleep Med 2007. [DOI: 10.1016/s1389-9457(07)70232-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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WITHDRAWN: Increased preference for standard versus palatable chow during long-term amylin treatment. Appetite 2006. [DOI: 10.1016/j.appet.2006.03.249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Bone mass in patients with primary breast cancer: Measurements of the calcaneus by ultrasonometry. J Clin Oncol 2005. [DOI: 10.1200/jco.2005.23.16_suppl.827] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Lost working days, productivity, and restraint use among occupants of motor vehicles that crashed in the United States. Inj Prev 2004; 10:314-9. [PMID: 15470014 PMCID: PMC1730133 DOI: 10.1136/ip.2004.005850] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND In 2001, 6.3 million passengers were involved in motor vehicle crashes. This study aimed to determine the number of work days lost as a result of motor vehicle crashes and factors that influenced people's return to work. METHODS This was a retrospective, population based cohort study of occupants in motor vehicles involved in crashes from the 1993-2001 Crashworthiness Data System produced by the National Highway Traffic Safety Administration. The sample population of people aged 18-65 years included two groups: occupants who survived and were working before the crash and occupants who were injured fatally and were estimated to have been working before the crash. Multivariate linear regression was used to analyze the impact of restraint use and injury type on return to work. RESULTS Overall, 30.1% of occupants of vehicles that crashed missed one or more days of work. A crash resulted in a mean 28.0 (95% confidence interval 15.8 to 40.1) days lost from work, including losses associated with fatalities. The 2.1 million working occupants of vehicles that crashed in 2001 lost a total of 60 million days of work, resulting in annual productivity losses of over $7.5 billion (2964 to 12 075). Unrestrained vehicle occupants accounted for $5.6 billion in lost productivity. CONCLUSIONS Motor vehicle crashes result in large and potentially preventable productive losses that are mostly attributable to fatal injuries.
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Abstract
The molecular basis for the embryonic and perinatal clinical forms of biliary atresia is largely undefined. In this study, we aimed to: 1) determine if the clinical forms can be differentiated at the transcriptional level, and 2) search for molecular mechanisms underlying phenotypic differences. To this end, we generated biotinylated cRNA probes from livers of age-matched infants with the embryonic (n = 5) and perinatal (n = 6) forms of biliary atresia at the time of diagnosis and hybridized them against the Affymetrix human HG-U133 A and B microarrays containing 44,760 gene products. Data filtering and two-way cluster analysis of the gene expression platform identified 230 genes with an expression profile that is highly distinctive of the clinical phenotypes. Functionally, the profile did not reveal a higher-order function for a specific cell type; instead, it uncovered a coordinated expression of regulatory genes. These regulatory genes were predominantly represented in the embryonic form (45% of genes), with a unique pattern of expression of genes involved in chromatin integrity/function (Smarca-1, Rybp, and Hdac3) and the uniform overexpression of five imprinted genes (Igf2, Peg3, Peg10, Meg3, and IPW), implying a failure to downregulate embryonic gene programs. In conclusion, embryonic and perinatal forms of biliary atresia are distinguished by gene expression profiling. The coordinate expression of regulators of chromatin structure/function and of imprinted genes provides evidence for a transcriptional basis for the pathogenesis of the embryonic form of biliary atresia. Further studies exploring these biological processes are required to determine the significance of these findings.
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Notes - Reactions of Sodium Phenylacetylide and Sodium Alkoxide with Tosyl and Mesyl Azides. J Org Chem 2003. [DOI: 10.1021/jo01101a604] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Production process monitoring by serial mapping of microbial carbon flux distributions using a novel Sensor Reactor approach: II--(13)C-labeling-based metabolic flux analysis and L-lysine production. Metab Eng 2003; 5:96-107. [PMID: 12850132 DOI: 10.1016/s1096-7176(03)00005-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Corynebacterium glutamicum is intensively used for the industrial large-scale (fed-) batch production of amino acids, especially glutamate and lysine. However, metabolic flux analyses based on 13C-labeling experiments of this organism have hitherto been restricted to small-scale batch conditions and carbon-limited chemostat cultures, and are therefore of questionable relevance for industrial fermentations. To lever flux analysis to the industrial level, a novel Sensor Reactor approach was developed (El Massaoudi et al., Metab. Eng., submitted), in which a 300-L production reactor and a 1-L Sensor Reactor are run in parallel master/slave modus, thus enabling 13C-based metabolic flux analysis to generate a series of flux maps that document large-scale fermentation courses in detail. We describe the successful combination of this technology with nuclear magnetic resonance (NMR) analysis, metabolite balancing methods and a mathematical description of 13C-isotope labelings resulting in a powerful tool for quantitative pathway analysis during a batch fermentation. As a first application, 13C-based metabolic flux analysis was performed on exponentially growing, lysine-producing C. glutamicum MH20-22B during three phases of a pilot-scale batch fermentation. By studying the growth, (co-) substrate consumption and (by-) product formation, the similarity of the fermentations in production and Sensor Reactor was verified. Applying a generally applicable mathematical model, which included metabolite and carbon labeling balances for the analysis of proteinogenic amino acid 13C-isotopomer labeling data, the in vivo metabolic flux distribution was investigated during subsequent phases of exponential growth. It was shown for the first time that the in vivo reverse C(4)-decarboxylation flux at the anaplerotic node in C. glutamicum significantly decreased (70%) in parallel with threefold increased lysine formation during the investigated subsequent phases of exponential growth.
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The reduction in apparent particle concentration with multiple strokes of the Owens jet dust counter. ACTA ACUST UNITED AC 2002. [DOI: 10.1088/0508-3443/4/10/107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Faith in stem cells. Stem Cells 2002; 19:269-70. [PMID: 11463945 DOI: 10.1634/stemcells.19-4-269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Radiation Therapy Oncology Group. Research Plan 2002-2006. Head and Neck Cancer Committee. Int J Radiat Oncol Biol Phys 2002; 51:39-43. [PMID: 11641013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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Abstract
Biliary atresia, a progressive sclerosis of the extrahepatic biliary tree that occurs only within the first 3 months of life, is one of the most common causes of neonatal cholestasis and accounts for over half of children who undergo liver transplantation. In biliary atresia, a number of prenatal or perinatal insults to the biliary tree appear to culminate in complete obliteration of the lumen of the extrahepatic biliary tree and continued injury and sclerosis of intrahepatic bile ducts, even after portoenterostomy is successful. A minority of cases of biliary atresia may be caused by defects in morphogenesis of the bile ducts. Potential etiologies for the more common perinatal form of biliary atresia include viral infections, immune-mediated bile duct injury, and autoimmune disease involving the bile ducts. Two viruses, reovirus and rotavirus, have received increasing attention as possible inciters of an immune-mediated injury to the biliary tree. Fas ligand upregulation and apoptosis of bile duct epithelia have been demonstrated in human specimens, as well as T-lymphocyte and macrophage activation in portal tracts. An experimental model using rotavirus infection in newborn mice has been useful in characterizing the mechanisms underlying bile duct injury. It is proposed that virally induced neoantigens displayed on biliary epithelium may play a role in initiating the immune processes involved in destruction of the extrahepatic bile duct and ongoing intrahepatic ductal injury in the perinatal form of biliary atresia. The short window of time after birth during which this disease presents suggests that immaturity of the neonatal immune system and genetic susceptibility also may be key factors. Delineation of the mechanisms underlying bile duct injury will be essential to the development of new potential therapies for this important pediatric disorder.
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Down-regulation of cell adhesion molecules LFA-1 and ICAM-1 after in vitro treatment with the anti-TNF-alpha agent thalidomide. Cell Mol Biol (Noisy-le-grand) 2001; 47:1105-14. [PMID: 11838958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
The tumor necrosis factor-alpha (TNF-alpha) inhibitor thalidomide is known to be a potent modulator of host immunity, a potential treatment for autoimmune disorders such as rheumatoid arthritis (RA) and a treatment for complications of HIV-1 infection. RA is an autoimmune disease of the joints that has been associated with hyperactivity of lymphocytes and other leukocytes, over-expression of pro-inflammatory cytokines (TNF-alpha and IL-1) and chronic debilitating inflammation. Thalidomide may play a role in RA treatment by altering leukocyte function through down-modulation of cell adhesion molecules necessary for leukocyte migration to inflammatory sites. The present study investigates down-regulation of cell adhesion molecules (ICAM-1 and LFA-1) and decreases in cell-cell contacts between human T leukemic (CEM) cells and human umbilical vein endothelial cells (HUVEC) after thalidomide exposure. CEM cells were cultured in RPMI 1640 medium with 0, 10 or 50 microg/ml thalidomide, stained with fluorescent monoclonal antibodies specific to ICAM-1 and LFA-1 and expression was measured with flow cytometry. For cell-cell adhesion measurements, monolayers of HUVEC cultured in Kaign's F-12 medium were incubated with thalidomide treated CEM cells stained with calcein AM. Specific cell adhesion between the two cell types was visualized with fluorescence microscopy. Thalidomide treatment significantly reduced cell adhesion molecule expression in a dose-dependent fashion and inhibited HUVEC/CEM cell adhesion. These data support the hypothesis that thalidomide has modulatory actions on leukocyte functions through expression of cell adhesion molecules.
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