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1.
Eur J Surg Oncol ; 49(12): 107100, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37918318

RESUMO

INTRODUCTION: In view of the high therapeutic value of surgical resection for intrahepatic cholangiocarcinomas (ICC), our study addresses the question of clinical management and outcome in case of borderline resectability requiring hypertrophy induction of the future liver remnant prior to resection. METHODS: Clinical data was collected of all primary ICC cases receiving major liver resection with or without prior portal vein embolization (PVE) from a single high-volume center. PVE was performed via a percutaneous transhepatic access. Propensity score matching was performed. Perioperative morbidity was assessed as well as long-term survival with a minimum follow-up of 36 months. RESULTS: No significant difference in perioperative morbidity was seen between the PVE and the control group. For the PVE group, median OS was 28 months vs. 37 months for the control group (p = 0.418), median DFS 18 and 14 months (p = 0.703). Disease progression during hypertrophy was observed in 38% of cases. Here, OS and DFS was reduced to 18 months (p = 0.479) and 6 months (p = 0.013), respectively. In case of positive N-status or multifocal tumor (MF+) OS was also reduced (18 vs. 26 months, p = 0.033; MF+: 9 vs. 36months p = 0.013). CONCLUSION: Our results suggest that the surgical therapy in case of borderline resectability offers acceptable results with non-inferior OS rates compared to cases without preoperative hypertrophy induction and comparable oncological features. In the presence of additional risk factors (multifocal tumor, lymph node metastasis, PD during hypertrophy) the OS is notably reduced.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Embolização Terapêutica , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/secundário , Veia Porta/cirurgia , Colangiocarcinoma/cirurgia , Embolização Terapêutica/métodos , Hepatectomia/métodos , Ductos Biliares Intra-Hepáticos/cirurgia , Neoplasias dos Ductos Biliares/cirurgia , Hipertrofia/etiologia , Hipertrofia/cirurgia , Resultado do Tratamento
2.
Acta Biomater ; 98: 186-195, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31352109

RESUMO

Volume stable barrier membranes made of magnesium are very promising in Guided Bone Regeneration (GBR) to treat periodontal bone defects in dentistry due to their excellent biocompatibility and biodegradability. During the degradation process the cells are exposed to the alteration of various parameters, so called physical cues, involving surface alterations due to the formed corrosion layer and medium alterations arising from the dissolved corrosion products. Cell migration of human gingival fibroblasts (HGF), as a crucial parameter for optimal healing process in GBR, has been investigated on magnesium membranes and revealed that medium alterations by dissolved corrosion products have a higher impact on cell migration than surface alterations. However, the effect of each altered medium parameter on cell migration has not been adequately studied, but their roles are crucial to explain the slower migration rate on magnesium surfaces compared to titanium and tissue culture plastic surfaces. Our study investigates the single effect of Mg2+, Ca2+, H2 and increased osmolality as well as the effect of magnesium extracts, which contain a dynamic mixture of previous parameters on cell migration, proliferation and viability of HGF. We showed that at 75 mM Mg2+ concentration and at 0 mM Ca2+, respectively, the cell migration rate is greatly reduced. In complex magnesium extract media, we found that a temporarily increased ratio of Mg2+ to Ca2+ conditioned a slow HGF migration rate. Based on these findings and the characterization of supernatants from HGF migration assays on Mg membranes, we propose, that the slower migration rate of HGF can be explained by the altered ratio of Mg2+ to Ca2+, caused by increasing concentrations of Mg2+ and decreasing concentrations of Ca2+ in the vicinity of the corroding Mg implant, combined with a constantly increased molecular hydrogen concentration in the supernatant. These results are cell type specific and should be checked carefully, if necessary, for Mg implant performance. STATEMENT OF SIGNIFICANCE: The study is providing a systematic approach to explain the main effects of extract medium parameters (physical cues) such as magnesium or calcium ion concentration, osmolality and dissolved molecular hydrogen and CO2 in cell culture media modified by co-incubating with corroding magnesium implants on the migration rate of human gingival fibroblasts (HGF). This study uncovers for the first time the combinatory effect of slightly increased molecular hydrogen and the change in Mg2+/Ca2+ ratio on HGF cell migration.


Assuntos
Implantes Absorvíveis , Fibroblastos/citologia , Gengiva/citologia , Magnésio/farmacologia , Cálcio/farmacologia , Movimento Celular/efeitos dos fármacos , Corrosão , Meios de Cultura , Fibroblastos/efeitos dos fármacos , Humanos , Hidrogênio/farmacologia , Íons
3.
Z Gastroenterol ; 53(1): 28-32, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25594704

RESUMO

OBJECTIVE: The purpose of this study was to evaluate potential causes of Transjugular intrahepatic portosystemic shunt (TIPS) dysfunction. MATERIAL AND METHODS: We retrospectively evaluated 26 patients who required TIPS revision (group I) and 24 patients who did not require any further intervention (group II) within the first two years following TIPS implantation. The distance of the distal end of the stent to the hepatocaval junction was measured. Furthermore, the angle between the stent and the portal vein (inflow) and the angle between the stent and the hepatic vein (outflow) were measured. Furthermore, the following data were evaluated: pre- and postinterventional portal pressure gradients, maximal postinterventional flow and blood values [C-reactive protein (CRP), bilirubin, glutamic-oxaloacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT)]. RESULTS: Compared with control subjects, patients who required TIPS revision showed a significantly longer distance from the distal end of the stent to the hepatocaval junction (I: 17.3 ±â€Š10 mm, II: 6.7 ±â€Š5.7 mm, p < 0.001). There was a statistically significant correlation between the above named distance and the time to revision (Pearson's correlation coefficient, r = 0.5, p = 0.01). In addition, patients with TIPS revision had a significantly larger angle of portalvenous inflow (alpha angle) than the control group (I: 100.5 ±â€Š31.5°, II: 64.5 ±â€Š31.6°, p < 0.001). CONCLUSION: Our results show that the distance from the end of the stent to the hepatocaval junction and the angle of portalvenous inflow are technical factors that may influence the shunt's patency rate. Of these two, the distance to the hepatocaval junction can be influenced easily by the interventionalist.


Assuntos
Sobrevivência de Enxerto/fisiologia , Veias Hepáticas/fisiologia , Circulação Hepática/fisiologia , Derivação Portossistêmica Transjugular Intra-Hepática , Stents , Grau de Desobstrução Vascular/fisiologia , Velocidade do Fluxo Sanguíneo , Análise de Falha de Equipamento , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Estudos Retrospectivos , Resultado do Tratamento
4.
Artigo em Inglês | MEDLINE | ID: mdl-26737168

RESUMO

Macrophages within the liver are of particular importance for a functional defense against bacterial infection. They exhibit a complex response to lipopolysaccharide and secrete a variety of pro-inflammatory cytokines and chemokines that both coordinate the immune response and regulate activity of the macrophages, themselves. In this context, the dynamic of pathway activation and gene expression is important for a better understanding of the role of activated macrophages in healthy and diseased states. Therefore, we present a representative model of LPS-induced macrophage activation that covers the principle regulatory motifs. Based on that, we propose a simplified model with a reduced number of states and parameters that allows estimation of transcription factor activity from gene expression data and can be easily extended to describe the full spectrum of gene regulation in LPS-activated macrophages.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Lipopolissacarídeos/toxicidade , Macrófagos/metabolismo , Modelos Biológicos , Fatores de Transcrição/metabolismo , Animais , Quimiocinas/metabolismo , Citocinas/metabolismo , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Camundongos , NF-kappa B/metabolismo , RNA Mensageiro/metabolismo
5.
Cell Death Differ ; 21(7): 1050-60, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24531538

RESUMO

CD8(+) T-cell functions are critical for preventing chronic viral infections by eliminating infected cells. For healthy immune responses, beneficial destruction of infected cells must be balanced against immunopathology resulting from collateral damage to tissues. These processes are regulated by factors controlling CD8(+) T-cell function, which are still incompletely understood. Here, we show that the interferon regulatory factor 4 (IRF4) and its cooperating binding partner B-cell-activating transcription factor (BATF) are necessary for sustained CD8(+) T-cell effector function. Although Irf4(-/-) CD8(+) T cells were initially capable of proliferation, IRF4 deficiency resulted in limited CD8(+) T-cell responses after infection with the lymphocytic choriomeningitis virus. Consequently, Irf4(-/-) mice established chronic infections, but were protected from fatal immunopathology. Absence of BATF also resulted in reduced CD8(+) T-cell function, limited immunopathology, and promotion of viral persistence. These data identify the transcription factors IRF4 and BATF as major regulators of antiviral cytotoxic T-cell immunity.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/fisiologia , Linfócitos T CD8-Positivos/fisiologia , Fatores Reguladores de Interferon/fisiologia , Vírus da Coriomeningite Linfocítica/imunologia , Animais , Apoptose , Linfócitos T CD8-Positivos/virologia , Células Cultivadas , Citotoxicidade Imunológica , Memória Imunológica , Ativação Linfocitária , Camundongos Endogâmicos C57BL , Camundongos Knockout
6.
Int J Pharm ; 448(1): 87-95, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23524124

RESUMO

The interaction of aqueous nanoparticle dispersions, e.g. based on monoolein/poloxamer 407, with blood components is an important topic concerning especially the parenteral way of administration. Therefore, the influence of human and porcine plasma on dispersed cubic phases was investigated. Particle size measurements of mixtures with plasma indicated a decrease in particle size. In cryo-transmission electron micrographs, different structures could be found, which arose from the dispersed cubic phases under plasma contact. Non-cubic structures on the particle surface were decomposed first. Several phase transitions with the formation of smaller and sometimes larger particle fractions were observed beside remaining cubic structures. A very low but detectable hemolytic activity was found for the dispersed cubic phases based on monoolein and poloxamer 407, when compared to the hemolytic activity of cubic phases based on monoolein and poloxamer 188, on soy phosphatidylcholine, glycerol dioleate and polysorbate 80 or the parenteral fat emulsion Lipofundin MCT 20%.


Assuntos
Sangue/efeitos dos fármacos , Lipídeos/farmacologia , Nanopartículas , Poloxâmero/farmacologia , Animais , Células Cultivadas , Emulsificantes/química , Emulsificantes/farmacologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/patologia , Hemólise/efeitos dos fármacos , Humanos , Lipídeos/química , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Nanopartículas/ultraestrutura , Poloxâmero/química , Suínos
7.
Z Gastroenterol ; 51(3): 287-9, 2013 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-23487357

RESUMO

BACKGROUND: Due to the lack of symptoms an enterothorax frequently remains undetected in adults. Most symptomatic patients complain about bowel obstruction and a surgical repair of the diaphragmatic defect, particularly with a mesh, is mandatory. METHODS: This report presents the case of a 72-year-old female patient with a history of an upside-down stomach presenting with a painless jaundice and signs of liver cirrhosis. CLINICAL COURSE: The preoperative work-up revealed an enterothorax with compression of the main bile duct. Explorative laparotomy showed a liver cirrhosis with distinct intrahepatic cholestasis, a hydropic gallbladder and confirmed a right-sided diaphragmatic defect with an enterothorax. After reposition of the intestine, a cholecystectomy, bile duct revision and the closure of the diaphragmatic defect using a mesh were performed. CONCLUSION: Diaphragmatic defects are the basis for the formation of an enterothorax which may be associated with a complicated clinical course. Therefore, in cases of coincidental diagnosis, even in asymptomatic patients, surgical repair should be performed in order to prevent serious complications as presented in this case.


Assuntos
Colestase Intra-Hepática/diagnóstico , Colestase Intra-Hepática/cirurgia , Hérnia Diafragmática/diagnóstico , Hérnia Diafragmática/cirurgia , Idoso , Colestase Intra-Hepática/etiologia , Diagnóstico Diferencial , Feminino , Hérnia Diafragmática/complicações , Humanos , Resultado do Tratamento
9.
Curr Mol Med ; 12(4): 494-501, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22376065

RESUMO

By exposing cells of the U118MG glioblastoma cell line to protoporphyrin IX (PPIX) in culture, we found that the 18 kDa mitochondrial translocator protein (TSPO) prevents intracellular accumulation of PPIX. In particular, TSPO knockdown by stable transfection of TSPO silencing siRNA vectors into U118MG cells leads to mitochondrial PPIX accumulation. In combination with light exposure, the PPIX accumulation led to cell death of the TSPO knockdown cells. In the sham control cells (stable transfection of scrambled siRNA vectors), TSPO expression remained high and no PPIX accumulation was observed. The prevention of PPIX accumulation by TSPO was not due to conversion of PPIX to heme in the sham control cells. Similar to TSPO knockdown, the reactive oxygen species (ROS) scavenger glutathione (GSH) also enhanced PPIX accumulation. This suggests that that ROS generation as modulated by TSPO activation may present a mechanism to prevent accumulation of PPIX.


Assuntos
Fármacos Fotossensibilizantes/farmacologia , Protoporfirinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Receptores de GABA/fisiologia , Morte Celular/efeitos dos fármacos , Morte Celular/efeitos da radiação , Linhagem Celular Tumoral , Sequestradores de Radicais Livres/farmacologia , Técnicas de Silenciamento de Genes , Glutationa/farmacologia , Heme/metabolismo , Humanos , Mitocôndrias/metabolismo , Fármacos Fotossensibilizantes/metabolismo , Protoporfirinas/metabolismo , Interferência de RNA , Receptores de GABA/genética , Receptores de GABA/metabolismo
10.
Z Gastroenterol ; 49(6): 728-36, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21638239

RESUMO

The phospholipidfloppase MDR3 (gene symbol: ABCB4) is expressed in the canalicular membrane of hepatocytes and mediates the biliary excretion of phosphatidylcholine, which is required for the formation of mixed micelles in bile. Several mutations of ABCB4 have been identified, which cause cholestatic liver diseases of varying severity including progressive familial intrahepatic cholestasis type 3 (PFIC-3), intrahepatic cholestasis of pregnancy (ICP) and the low phospholipid associated cholelithiasis syndrome (LPAC). Here, we report on four new (S1076N; L 23Hfs16X; c.286 + 1G > A; Q 1181E) and one known (S27G) MDR3 mutations in eight patients of three families. The patients presented with a wide spectrum of liver diseases. The clinical presentation and decisive laboratory findings or the association to a trend-setting family history led to the identification of the genetic background in these patients. Even the same mutation may be associated with varying disease progression.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Envelhecimento/genética , Colestase Intra-Hepática/diagnóstico , Colestase Intra-Hepática/genética , Predisposição Genética para Doença/genética , Variação Genética/genética , Mutação/genética , Adulto , Pré-Escolar , Heterozigoto , Humanos , Lactente , Masculino , Linhagem
11.
Eur J Med Res ; 15: 319-22, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20696645

RESUMO

INTRODUCTION: Streptococcus intermedius - a member of the Streptococcus anginosus group - is part of the normal microbial flora of the oral cavity. Despite being regarded as a harmless apathogenic commensal, Streptococcus intermedius has been described to cause abscesses in various locations of the body. CASE PRESENTATION: We report the clinical case and course of treatment of a 18-year-old male patient presenting with multiple hepatic abscesses associated with an untreated pyogenic dental infection. CONCLUSION: Streptococcus intermedius can cause liver abscesses emerging from dental infectious foci even in previously healthy patients without underlying innate or aquired immunodeficiency. The case illustrates the potential danger and underestimated risk associated with untreated dental infections.


Assuntos
Infecção Focal Dentária/complicações , Abscesso Hepático Piogênico/microbiologia , Infecções Estreptocócicas/complicações , Streptococcus intermedius/isolamento & purificação , Infecção Focal Dentária/diagnóstico , Humanos , Imunocompetência , Abscesso Hepático Piogênico/diagnóstico , Masculino , Dente Molar/microbiologia , Infecções Estreptocócicas/diagnóstico , Adulto Jovem
12.
Br J Nutr ; 101(7): 961-6, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19353762

RESUMO

A study was conducted in healthy elderly living independently in senior housing to assess the impact of a probiotic yoghurt supplement on small intestinal bacterial overgrowth. Twenty-three participants with positive and thirteen participants with negative hydrogen breath test were studied before and after a period of 4 weeks of probiotic yoghurt administration. Intestinal permeability, plasma endotoxin levels, phagocytic activity of leucocytes, cytokine production by monocytes and free radical response of neutrophils were determined. Intestinal permeability was similar for the two groups and was unaffected by probiotic treatment. Both plasma endotoxin levels and the basal phagocytic activity of leucocytes decreased after yoghurt intake in the two groups. Exposure of monocytes and neutrophils ex vivo led to an increased cytokine response and free radical response, respectively. The normalisation of the various cytokine responses was more apparent in the group with positive breath test. In addition, the plasma levels of lipoplysaccharide binding protein and soluble CD14, lipoplysaccharide pattern recognition receptors and surrogate markers of lipoplysaccharide permeability were diminished by the end of the study. In conclusion, probiotic administration in the elderly normalises the response to endotoxin, and modulates activation markers in blood phagocytes, and therefore may help reduce low-grade chronic inflammation.


Assuntos
Infecções Bacterianas/dietoterapia , Ileíte/dietoterapia , Mucosa Intestinal/microbiologia , Intestino Delgado , Probióticos/administração & dosagem , Iogurte , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Infecções Bacterianas/diagnóstico , Translocação Bacteriana , Testes Respiratórios , Estudos de Casos e Controles , Citocinas/metabolismo , Endotoxemia/dietoterapia , Feminino , Seguimentos , Humanos , Ileíte/diagnóstico , Ileíte/microbiologia , Absorção Intestinal , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Fagocitose , Espécies Reativas de Oxigênio/análise , Estatísticas não Paramétricas
13.
Alcohol ; 42(5): 349-61, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18504085

RESUMO

This report is a summary of the symposium on Alcohol, Intestinal Bacterial Growth, Intestinal Permeability to Endotoxin, and Medical Consequences, organized by National Institute on Alcohol Abuse and Alcoholism, Office of Dietary Supplements, and National Institute of Diabetes and Digestive and Kidney Diseases of National Institutes of Health in Rockville, Maryland, October 11, 2006. Alcohol exposure can promote the growth of Gram-negative bacteria in the intestine, which may result in accumulation of endotoxin. In addition, alcohol metabolism by Gram-negative bacteria and intestinal epithelial cells can result in accumulation of acetaldehyde, which in turn can increase intestinal permeability to endotoxin by increasing tyrosine phosphorylation of tight junction and adherens junction proteins. Alcohol-induced generation of nitric oxide may also contribute to increased permeability to endotoxin by reacting with tubulin, which may cause damage to microtubule cytoskeleton and subsequent disruption of intestinal barrier function. Increased intestinal permeability can lead to increased transfer of endotoxin from the intestine to the liver and general circulation where endotoxin may trigger inflammatory changes in the liver and other organs. Alcohol may also increase intestinal permeability to peptidoglycan, which can initiate inflammatory response in liver and other organs. In addition, acute alcohol exposure may potentiate the effect of burn injury on intestinal bacterial growth and permeability. Decreasing the number of Gram-negative bacteria in the intestine can result in decreased production of endotoxin as well as acetaldehyde which is expected to decrease intestinal permeability to endotoxin. In addition, intestinal permeability may be preserved by administering epidermal growth factor, l-glutamine, oats supplementation, or zinc, thereby preventing the transfer of endotoxin to the general circulation. Thus reducing the number of intestinal Gram-negative bacteria and preserving intestinal permeability to endotoxin may attenuate alcoholic liver and other organ injuries.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Translocação Bacteriana/efeitos dos fármacos , Endotoxinas/metabolismo , Etanol/efeitos adversos , Bactérias Gram-Negativas/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Acetaldeído/metabolismo , Consumo de Bebidas Alcoólicas/metabolismo , Animais , Avena/metabolismo , Queimaduras/metabolismo , Endotoxinas/sangue , Receptores ErbB/metabolismo , Glutamina/metabolismo , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Negativas/metabolismo , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Intestinos/microbiologia , Hepatopatias Alcoólicas/etiologia , Hepatopatias Alcoólicas/metabolismo , Óxido Nítrico/metabolismo , Permeabilidade , Probióticos/uso terapêutico , Zinco/metabolismo
14.
Handb Exp Pharmacol ; (186): 67-103, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18491049

RESUMO

There is increasing awareness that processes, such as development, aging and cancer, are governed, to a considerable extent, by epigenetic processes, such as DNA and histone modifications. The sites of these modifications in turn reflect their position and role in the nuclear architecture. Since epigenetic changes are easier to reverse than mutations, drugs that remove or add the chemical tags are at the forefront of research for the treatment of cancerous and inflammatory diseases. This review will use selected examples to develop a unified view that might assist the systematic development of novel therapeutic regimens.


Assuntos
DNA/metabolismo , Sistemas de Liberação de Medicamentos , Regiões de Interação com a Matriz/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Desenho de Fármacos , Epigênese Genética/fisiologia , Humanos , Regiões de Interação com a Matriz/fisiologia , Neoplasias/tratamento farmacológico , Neoplasias/fisiopatologia
16.
Biochem Soc Trans ; 35(Pt 3): 612-7, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17511663

RESUMO

High-throughput technologies now afford the opportunity to directly determine the distribution of MARs (matrix attachment regions) throughout a genome. The utility of cosmid and oligonucleotide platforms to identify human chromosome 16 MARs from preparations that employed LIS (lithium di-iodosalicylic acid) and NaCl extraction protocols was examined. The effectiveness of the platforms was then evaluated by Q-PCR (quantitative real-time PCR). Analysis revealed that caution must be exercised, since the representation of non-coding regions varies among platforms. Nevertheless, several interesting trends were revealed. We expect that these technologies will prove useful in systems approaches directed towards defining the role of MARs in various cell types and cellular processes.


Assuntos
Matriz Nuclear/genética , Matriz Nuclear/metabolismo , Sítios de Ligação/genética , Cromossomos Humanos Par 16/genética , Cromossomos Humanos Par 16/metabolismo , Genoma Humano , Humanos , Análise de Sequência com Séries de Oligonucleotídeos
17.
Gut ; 55(10): 1475-83, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16527836

RESUMO

BACKGROUND: The hepatitis C virus (HCV) establishes chronic infection by incompletely understood mechanisms. The non-structural (NS) 3/4A protease/helicase has been proposed as a key complex in modulating the infected hepatocyte, although nothing is known about the effects this complex exerts in vivo. AIM: To generate mice with stable and transient hepatocyte expression of the HCV NS3/4A proteins to study its effects in vivo. METHODS: NS3/4A expression was determined by western blot and immunohistochemistry. Two independent pathologists determined the liver histology. Hepatic immunity was characterised by quantifying intrahepatic immune cell subsets. Liver damage was induced using carbon tetrachloride (CCl(4)), lipopolysaccaride (LPS), tumour necrosis factor alpha (TNFalpha), and anti-Fas antibody. RESULTS: Expression of NS3/4A was restricted to the cytoplasm of hepatocytes, and did not cause liver cancer or any spontaneous liver pathology. However, the presence of NS3/4A modulated the intrahepatic immunity, as follows: first, the CD4+ T cell and type I/II dendritic cell subsets were reduced in transgenic livers; second, NS3/4A protected hepatocytes from liver damage mediated in vivo by CCl(4), LPS, TNFalpha, but not FAS; and third, both stable and transiently NS3/4A transgenic mice were resistant to lethal doses of liver targeted TNFalpha, and the resistance could be reverted by treatment with a p38 mitogen activated protein kinase inhibitor (MAPK). CONCLUSIONS: Hepatic expression of NS3/4A does not induce spontaneous liver disease. NS3/4A does, however, alter the intrahepatic immune cell subsets and protects hepatocytes against TNFalpha induced liver damage in vivo. The TNFalpha resistance can be reverted by treatment with a p38 MAPK inhibitor. This represents a new immune evasion strategy conferred by NS3/4A.


Assuntos
Hepacivirus/imunologia , Hepatopatias/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Hepatócitos/metabolismo , Imuno-Histoquímica , Subpopulações de Linfócitos/imunologia , Camundongos , Camundongos Transgênicos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
18.
Z Gastroenterol ; 44(2): 167-72, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16456758

RESUMO

BACKGROUND: Whole gut lavage with a polyethylene glycol electrolyte solution (PEG) is a common bowel cleansing method for diagnostic and therapeutic colon interventions. Absorption of orally administered PEG from the gastrointestinal tract in healthy human beings is generally considered to be poor. In patients with inflammatory bowel disease (IBD), intestinal permeability and PEG absorption were previously reported to be higher than in normal subjects. In the current study, we investigated the absorption of PEG 3350 in patients undergoing routine gut lavage. METHODS AND RESULTS: Urine specimens were collected for 8 hours in 24 patients undergoing bowel cleansing with PEG 3350 for colonoscopy. The urinary excretion of PEG 3350, measured by size exclusion chromatography, ranged between 0.01 and 0.51 % of the ingested amount, corresponding to 5.8 and 896 mg in absolute amounts, respectively. Mean PEG excretion in patients with impaired mucosa such as inflammation or ulceration of the intestine (0.24 % +/- 0.19, n = 11) was not significantly higher (p = 0.173) compared to that in subjects with macroscopically normal intestinal mucosa (0.13 % +/- 0.13, n = 13). CONCLUSION: The results indicate that intestinal absorption of PEG 3350 is higher than previously assumed and underlies a strong inter-individual variation. Inflammatory changes of the intestine do not necessarily lead to a significantly higher permeability of PEG.


Assuntos
Colonoscopia/métodos , Doenças Inflamatórias Intestinais/patologia , Doenças Inflamatórias Intestinais/urina , Polietilenoglicóis/metabolismo , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Catárticos/administração & dosagem , Catárticos/análise , Humanos , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/análise , Urinálise
19.
Alcohol Clin Exp Res ; 29(11 Suppl): 166S-71S, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16344604

RESUMO

It is generally accepted that activation of the innate immune system and increased release of pro-inflammatory cytokines and other mediators plays an important role in the development of alcoholic liver disease (ALD). The mechanisms involved in the ethanol-induced activation of monocytes/macrophages (including Kupffer cells) are however, still a matter of debate. The brief review will summarize the published data from the literature on the two main pathomechanisms discussed until now: I) Gut-derived bacterial toxins, specially endotoxin; and II) metabolic changes induced by alcohol oxidation (independent of mechanism I). For pathomechanism I, clear evidence has been published from numerous groups: Alcohol induces mucosal injury in the upper gastrointestinal tract and leads to marked increase in the permeability of the gut mucosa to macromolecules such as endotoxin. The resulting endotoxemia then leads to activation of Kupffer cells and other macrophages. The increased release of pro-inflammatory mediators (e.g., TNF-alpha, Il-1, reacting oxygen species) and infiltration of other inflammatory cells (e.g., neutrophils) finally causes liver damage. Regarding the second pathomechanism it has repeatedly been argued that the metabolic alterations which are induced by chronic administration of ethanol to rats or mice might increase the sensitivity of monocytes/macrophages to secrete TNF-alpha and other pro-inflammatory mediators thereby increasing the susceptibility to ethanol-induced liver injury. However, in all feeding experiments the effect of ethanol on intestinal permeability and enhanced translocation of bacterial toxins (endotoxin) is likely to occur (or at least cannot be excluded). The latter holds true also for experiments using isolated macrophages/Kupffer cells from ethanol fed animals. Therefore, to clarify whether or not alterations related to ethanol metabolism ("direct" effects of ethanol) contribute to the activation of the innate immune system studies using germ-free animals are needed to exclude the "indirect" effect of ethanol via gut-derived bacterial toxins.


Assuntos
Toxinas Bacterianas/metabolismo , Etanol/farmacologia , Imunidade Inata/efeitos dos fármacos , Absorção Intestinal/efeitos dos fármacos , Hepatopatias Alcoólicas/imunologia , Fígado/imunologia , Animais , Endotoxemia/etiologia , Etanol/metabolismo , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/microbiologia , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Lipopolissacarídeos/metabolismo , Fígado/fisiopatologia , Hepatopatias Alcoólicas/fisiopatologia , Fator de Necrose Tumoral alfa/metabolismo
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