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1.
Digestion ; 86(3): 218-27, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22964578

RESUMEN

BACKGROUND: Chronic hepatitis C virus genotype 1 (HCV-G1) infection is treated with pegylated interferon-α and ribavirin. Predictive factors for treatment success are even more important now as direct-acting antiviral agents are available. METHODS: Clinical and laboratory parameters were analyzed by uni- and multivariate statistical means in 264 patients with HCV-G1 infections with regard to treatment outcome. RESULTS: The overall sustained virological response (SVR) rate was 44%. Univariate analyses revealed SVRs to be associated with age, high alanine aminotransferase (ALT) and low γ-glutamyltransferase (γ-GT) serum activities, a low pretreatment γ-GT/ALT ratio, rapid virological response (RVR), and absence of steatosis. Multivariate analyses unveiled IL28B rs12979860 genotype (CC vs. CT: OR = 2.8, CI: 1.5-4.9, p = 0.001; CC vs. TT: OR = 7.1, CI: 3.1-16.7, p < 0.001), low pretreatment γ-GT/ALT ratio (OR = 2.5, CI: 1.7-3.3, p < 0.001), age (OR = 0.96, CI: 0.94-0.98, p = 0.001) and RVR (OR = 4.18, CI: 2.85-8.65, p < 0.001) to be significantly related to treatment outcome. Patients with the IL28B rs12979860 CC genotype and a low pretreatment γ-GT/ALT ratio achieved the highest rate of a SVR with the highest predictive values (OR = 26.7, 95% CI: 10-71.1, p < 0.0001). CONCLUSION: The pretreatment γ-GT/ALT ratio significantly enhances the predictability of the IL28B genotype. Employing this combination will help to identify patients who will most likely benefit from an interferon-α-based combination therapy in a nontriaged ordinary setting.


Asunto(s)
Alanina Transaminasa/sangre , Hepacivirus/genética , Hepatitis C Crónica/virología , Interleucinas/genética , Polimorfismo Genético , ARN Viral/análisis , gamma-Glutamiltransferasa/sangre , Adulto , Anciano , Antivirales/uso terapéutico , ADN/genética , Femenino , Genotipo , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/metabolismo , Humanos , Interferones , Interleucinas/metabolismo , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Adulto Joven
2.
Am J Transplant ; 12(10): 2601-7, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22813081

RESUMEN

Liver transplant recipients are at high risk of developing acute and chronic renal failure. Moreover, introduction of the model for end-stage liver disease (MELD) score for primary allocation of liver grafts favors patients with pretransplant kidney dysfunction, which in turn have a higher risk of posttransplant renal failure. Calcineurin inhibitors (CNI) further increase the risk of renal failure and therefore sparing CNI with the use of mycophenolate mofetil (MMF) may improve renal function. MMF may either be used de novo in the immediate posttransplant period in combination with low-dose CNI (scenario 1) or patients that receive immunosuppression based on CNI may be converted to MMF in combination with minimization or elimination of CNI (scenario 2). Although many retrospective cohort studies and nonrandomized trials have implicated efficacy of this approach the evidence from randomized controlled studies has not been summarized. In the current review we report the results of a systematic review and meta-analysis of randomized controlled trials.


Asunto(s)
Inhibidores de la Calcineurina , Inmunosupresores/uso terapéutico , Trasplante de Hígado , Ácido Micofenólico/análogos & derivados , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Ácido Micofenólico/uso terapéutico
4.
Comp Immunol Microbiol Infect Dis ; 34(1): 3-10, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19906427

RESUMEN

Four DNA vaccines against BoHV-1 were evaluated for their efficacy in calves. Twelve animals were divided into four groups which were injected with four different DNA vaccines: pVAX-tgD (Vaccine A); pVAX-tgD co-immunised with pVAX-48CpG (Vaccine B); pVAX-UbiLacI-tgD-L (Vaccine C); pVAX-UbiLacI-tgD-L co-immunised with pVAX-48CpG (Vaccine D). Three additional calves were given the plasmid vector and served as controls. Ninety days after the first vaccination all calves were challenge infected with BoHV-1. All animals developed a severe form of infections bovine rhinotracheitis. Only the calves given the pVAX-tgD co-immunised with pVAX-48CpG (Vaccine B) developed humoral antibodies against BoHV-1 between 56 and 90 days after the first vaccination, whereas in calves of other groups and in the controls, antibodies appeared only after the infection. In the calves vaccinated with either pVAX-tgD (Vaccine A) or pVAX-tgD combined with pVAX-48CpG (Vaccine B), BoHV-1-specific IFN-γ secreting cells were detected in PBMCs 90 days after the first vaccination and their number increased after challenge exposure. In the other groups the IFN-γ secreting cells were detected after virus infection and at low values.


Asunto(s)
Herpesvirus Bovino 1/inmunología , Rinotraqueítis Infecciosa Bovina/prevención & control , Vacunas de ADN/inmunología , Vacunas de ADN/normas , Vacunas Virales/inmunología , Vacunas Virales/normas , Animales , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Bovinos , Ensayo de Inmunoadsorción Enzimática , Herpesvirus Bovino 1/genética , Inmunidad Humoral/inmunología , Rinotraqueítis Infecciosa Bovina/inmunología , Rinotraqueítis Infecciosa Bovina/patología , Interferón gamma/metabolismo , Ganglios Linfáticos/patología , Vacunas de ADN/administración & dosificación , Vacunas de ADN/genética , Proteínas Virales/genética , Proteínas Virales/inmunología , Vacunas Virales/administración & dosificación , Esparcimiento de Virus
6.
Transplant Proc ; 42(9): 3880-2, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21094876

RESUMEN

In inflammatory bowel disease refractory to established therapies, treatment with biological agents such as monoclonal tumor necrosis factor-α antibodies is an established therapeutic option. However, application in renal allograft recipients is either not licensed or has not yet been systematically examined. Herein, we present 2 case reports of renal allograft recipients who had steroid-refractory ulcerative colitis who demonstrated improvement of symptoms after treatment with infliximab, without signs of effect on transplant function. In both patients, stool frequency decreased significantly. Colonoscopy controls and histologic examination after initiation of treatment revealed a state of remission. Renal function parameters and drug concentrations remained constant.


Asunto(s)
Antiinflamatorios/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Resistencia a Medicamentos , Inmunosupresores/uso terapéutico , Enfermedades Renales/cirugía , Trasplante de Riñón , Esteroides/uso terapéutico , Adulto , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/diagnóstico , Colonoscopía , Quimioterapia Combinada , Femenino , Humanos , Inmunosupresores/efectos adversos , Infliximab , Enfermedades Renales/complicaciones , Masculino , Persona de Mediana Edad , Trasplante Homólogo , Resultado del Tratamiento
7.
Case Rep Oncol ; 3(2): 154-159, 2010 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-20740189

RESUMEN

BACKGROUND: Second as well as higher-line therapies have a significant influence on progression-free and overall survival of metastatic colorectal cancer patients. However, treatment of late-stage disease remains suboptimal. Therefore, the introduction of new, effective and well-tolerated agents is of major importance. Case Reports: Here we describe the cases of 2 patients with metastatic KRAS wild-type colorectal cancer who received a fourth-line monotherapy with panitumumab after failure of 5-fluorouracil, irinotecan, oxaliplatin, and bevacizumab. RESULTS: Both patients achieved a partial remission, and for 11.5 and 18 months, respectively, they had a stable disease with initial reduction in the tumor marker carcinoembryonic antigen. Both patients reported a good tolerability of the treatment with improved quality of life (compared to receiving combined chemotherapy). CONCLUSION: Panitumumab monotherapy is an effective and well tolerated treatment of metastatic colorectal cancer in extensively pretreated KRAS wild-type patients. Our data have shown a response to panitumumab monotherapy for more than 11 months.

8.
Minerva Gastroenterol Dietol ; 55(4): 409-23, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19942826

RESUMEN

Amongst the different solid tumors, gastrointestinal stromal tumors (GISTs) can be considered as orphan tumors, as overall, they are rather rare. Up-to now, they do not find mention within epidemiological tumor statistics of the Western population. However, with the combined use of clinical and laboratory diagnostic tools these mesenchymal tumors are not only discovered more often, but also have been recognized as model tumors for the therapy with tyrosine kinase inhibitors. This review tries to give an overview of the clinical presentation and of the diagnostics employed for identifying these tumors. It also summarizes the recent advances in treatment especially in intermediate and high risk cases.


Asunto(s)
Tumores del Estroma Gastrointestinal , Benzamidas , Ensayos Clínicos Fase II como Asunto , Ensayos Clínicos Fase III como Asunto , Tumores del Estroma Gastrointestinal/diagnóstico , Tumores del Estroma Gastrointestinal/diagnóstico por imagen , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Tumores del Estroma Gastrointestinal/epidemiología , Tumores del Estroma Gastrointestinal/genética , Tumores del Estroma Gastrointestinal/terapia , Gastroscopía , Histocitoquímica , Humanos , Mesilato de Imatinib , Inmunofenotipificación , Imagen por Resonancia Magnética , Mutación , Piperazinas/uso terapéutico , Tomografía de Emisión de Positrones , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Pirimidinas/uso terapéutico , Factores de Riesgo , Tomografía Computarizada por Rayos X
9.
Growth Horm IGF Res ; 19(1): 51-60, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18632293

RESUMEN

OBJECTIVE: The acute-phase response (APR), a cytokine-induced defense reaction of the body that enhances the innate immunity mechanisms directed to eliminate the noxious agent and restrict the area of damage, is accompanied by numerous alterations of the IGF axis. The liver is a central organ of both the IGF system and the APR because it releases most of IGF-I and IGFBP-1 in the circulation and is the main target organ for acute-phase-cytokines such as IL-6. METHODS: In the current work the expression of IGF-I and IGFBP-1 was studied in the liver and extrahepatic tissues in a rat model of localized inflammation induced by intramuscular injection of turpentine oil (TO). The mRNA expression of IGF-I and IGFBP-1 was determined by Northern blot analysis and quantitative RT-PCR. Circulating levels of IGF-I and IGFBP-1 were evaluated by radioimmunoassay and [(125)I]-IGF-I ligand blotting, respectively. RESULTS: Administration of TO to the rats led to a significant reduction of IGF-I gene expression in the liver and spleen. These changes were accompanied by a reduction of serum IGF-I concentrations to approximately 50% of levels observed in control rats. In contrast to IGF-I, IGFBP-1 mRNA expression was rapidly elevated in the livers of TO-treated rats. IGFBP-1 transcripts were already detectable at 30 min after TO injection and reached their maximal levels by 6h. IGFBP-1 gene expression was also increased in the kidneys. This elevation, however, was delayed and less prominent than in the liver. CONCLUSIONS: Our data demonstrate that localized inflammation induced by intramuscular TO injection is accompanied not only by decreased IGF-I but also by increased IGFBP-1 gene expression explaining at least in part the catabolic changes of metabolism observed during the acute-phase response.


Asunto(s)
Reacción de Fase Aguda/inmunología , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Reacción de Fase Aguda/inducido químicamente , Reacción de Fase Aguda/metabolismo , Animales , Citocinas/inmunología , Inflamación/inducido químicamente , Inflamación/inmunología , Inflamación/metabolismo , Riñón/metabolismo , Hígado/metabolismo , Masculino , Especificidad de Órganos , Ratas , Ratas Wistar , Bazo/metabolismo , Trementina
10.
J Physiol Pharmacol ; 59 Suppl 1: 107-17, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18802219

RESUMEN

The liver is the largest organ of the body. It is located between the portal and the general circulation, between the organs of the gastrointestinal tract and the heart. The main function of the liver is to take up nutrients, to store them, and to provide nutrients to the other organs. At the same time has the liver to take up potentially damaging substances like bacterial products or drugs delivered by the portal blood or microorganisms, which reach the circulation. The liver is not only an important power and sewage treatment plant of the body. In fact, the liver is probably the best example for a cheap recycling system. Both parenchymal and nonparenchymal liver cells participate in the clearance activities. The function of the liver as clearance organ, however, harbors the danger that the substances that should be degraded and/or eliminated lead to tissue damage. Thus, effective defense mechanisms are necessary. Among the nonparenchymal cells Kupffer cells, sinusoidal endothelial cells, and natural killer (NK) lymphocytes exert cellular defense functions for the whole body but also for the liver itself. Furthermore, each cell type of the liver, including the hepatocytes, possesses its own defense apparatus.


Asunto(s)
Hepatitis/patología , Hepatitis/fisiopatología , Regeneración Hepática , Hígado/patología , Hígado/fisiopatología , Animales , Intoxicación por Tetracloruro de Carbono/patología , Intoxicación por Tetracloruro de Carbono/fisiopatología , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Enfermedad Hepática Inducida por Sustancias y Drogas/fisiopatología , Rayos gamma , Hepatitis/etiología , Hepatitis Viral Animal/patología , Hepatitis Viral Animal/fisiopatología , Hepatocitos/patología , Cirrosis Hepática/patología , Cirrosis Hepática/fisiopatología , Traumatismos Experimentales por Radiación/patología , Traumatismos Experimentales por Radiación/fisiopatología , Ratas
11.
Exp Clin Endocrinol Diabetes ; 116(8): 461-7, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18770489

RESUMEN

BACKGROUND: Diabetes in liver cirrhosis is associated with a blunted insulin response, which might be explained by an impaired release of the incretin hormone glucagon-like peptide 1 (GLP-1) into the portal circulation. AIMS: To investigate basal and stimulated portal venous and peripheral GLP-1 concentrations in non-diabetic (ND) and diabetic (D) patients with liver cirrhosis undergoing transjugular intrahepatic portosystemic stent shunt (TIPSS) implantation. PATIENTS AND METHODS: After elective TIPSS portalvenous and peripheral probes were drawn from 10 ND and 10 D patients with stable liver disease during an oral metabolic test and plasma glucose, immunoreactive GLP-1, insulin and C-peptide were measured. RESULTS: The study meal led to a significant rise in portal GLP-1 levels in ND and D. Basal and stimulated portal GLP-1 concentrations were not significantly different between ND and D. Peripheral GLP-1 did not differ significantly from portal venous levels. Insulin response in ND was more pronounced in the portal blood than in the periphery and was absent in D. CONCLUSION: TIPSS allows a direct evaluation of hormonal changes in the portal circulation during an oral metabolic tolerance test. A disturbed GLP-1 secretion does not play a role in blunting the insulin response observed in patients with hepatogenous diabetes.


Asunto(s)
Complicaciones de la Diabetes/sangre , Ingestión de Alimentos , Péptido 1 Similar al Glucagón/sangre , Circulación Hepática , Cirrosis Hepática Alcohólica/sangre , Cirrosis Hepática/sangre , Sistema Porta , Derivación Portosistémica Intrahepática Transyugular , Adulto , Anciano , Femenino , Humanos , Insulina/metabolismo , Insulina/fisiología , Secreción de Insulina , Cirrosis Hepática/complicaciones , Cirrosis Hepática/cirugía , Cirrosis Hepática Alcohólica/complicaciones , Cirrosis Hepática Alcohólica/cirugía , Masculino , Persona de Mediana Edad , Stents
12.
J Pathol ; 216(2): 225-35, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18729075

RESUMEN

Gastrointestinal stromal tumours (GISTs) with deletions in KIT exon 11 are characterized by higher proliferation rates and shorter disease-free survival times, compared to GISTs with KIT exon 11 point mutations. Up-regulation of cyclin D is a crucial event for entry into the G1 phase of the cell cycle, and links mitogenic signalling to cell proliferation. Signalling from activated KIT to cyclin D is directed through the RAS/RAF/ERK, PI3K/AKT/mTOR/EIF4E, and JAK/STATs cascades. ERK and STATs initiate mRNA transcription of cyclin D, whereas EIF4E activation leads to increased translation efficiency and reduced degradation of cyclin D protein. The aim of the current study was to analyse the mRNA and protein expression as well as protein phosphorylation of central hubs of these signalling cascades in primary GISTs, to evaluate whether tumours with KIT exon 11 deletions and point mutations differently utilize these pathways. GISTs with KIT exon 11 deletions had significantly higher mitotic counts, higher proliferation rates, and shorter disease-free survival times. In line with this, they had significantly higher expression of cyclin D on the mRNA and protein level. Furthermore, there was a significantly higher amount of phosphorylated ERK1/2, and a higher protein amount of STAT3, mTOR, and EIF4E. PI3K and phosphorylated AKT were also up-regulated, but this was not significant. Ultimately, GISTs with KIT exon 11 deletions had significantly higher phosphorylation of the central negative cell-cycle regulator RB. Phosphorylation of RB is accomplished by activated cyclin D/CDK4/6 complex, and marks a central event in the release of the cell cycle. Altogether, these observations suggest increased KIT signalling with up-regulation of cyclin D as the basis for the unfavourable clinical course in GISTs with KIT exon 11 deletions.


Asunto(s)
Ciclinas/genética , Tumores del Estroma Gastrointestinal/genética , Proteínas Proto-Oncogénicas c-kit/genética , Regulación hacia Arriba , Anciano , Anciano de 80 o más Años , Proliferación Celular , Ciclina D , Ciclinas/metabolismo , Supervivencia sin Enfermedad , Exones , Femenino , Tumores del Estroma Gastrointestinal/mortalidad , Tumores del Estroma Gastrointestinal/patología , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Análisis por Matrices de Proteínas , Proteínas Proto-Oncogénicas c-kit/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Eliminación de Secuencia , Transducción de Señal/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología
13.
Z Gastroenterol ; 46(7): 712-24, 2008 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-18618384

RESUMEN

On consideration of current medical and socio-economical factors, palliative care is becoming an increasingly important aspect of modern medicine in Germany. The German Society for Digestive and Metabolic Disorders (DGVS) has taken this into account by founding the working group "Palliative Gastroenterology". Patients with gastrointestinal malignancies or advanced non-malignant liver disease represent an important group that benefits from palliative care. Approximately 80 % of all palliative care patients suffer from gastrointestinal symptoms and endoscopic procedures performed by gastroenterologists play an important role in relieving symptoms such as obstruction. It is the object of this paper to evaluate the role of gastroenterologists in palliative medicine. It will give a brief definition, a historical review and the current legal background for palliative care in Germany and examine special aspects of ethics, decision making and research. Considering the current evidence on palliative endoscopic procedures this paper wants to establish the role of the gastroenterologist in palliative care far beyond the mere practicalities of endoscopy. The gastroenterologist is a crucial element of the interdisciplinary palliative care team and a partner to the patient in the process of decision-making. Finally, it is demonstrated how palliative care structures can be implemented in the setting of a university acute-care hospital.


Asunto(s)
Gastroenterología/métodos , Gastroenterología/tendencias , Neoplasias Gastrointestinales/rehabilitación , Cuidados Paliativos/métodos , Cuidados Paliativos/tendencias , Alemania , Humanos
14.
J Cardiovasc Surg (Torino) ; 49(4): 533-7, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18665118

RESUMEN

AIM: Valuable models of chronic heart failure to perform histological studies are scarce. The authors aimed at investigating histological changes of the heart, lung, liver and kidneys in a stable and reproducible animal model of chronic heart failure in sheep. METHODS: In 8 sheep (N.=8, 77+/-2 kg) chronic heart failure was induced by multiple sequential microembolization through bolus injection of polysterol microspheres (90 microm, N=25 000) into the left main coronary artery. Microembolization (ME) was repeated up to three times in two to three week intervals until animals started to develop stable signs of heart failure. Therefore, clinical and hemodynamic parameters were measured (Troponin T, heart and respiratory rate, cardiac output) after each embolization. Clinical examination was carried out by a veterinarian. All animals were followed for 3 months after first microembolization and then euthanized for histological examination. Histological data of the heart, lung, liver and the kidneys were analyzed in hematoxylin-eosin (HE) stains (10x, 25x, 100x) at baseline (control group) and at 3 months after first ME. Additionally preparations of heart tissue were stained with Picro-Sirius-Red (PSR) for planimetric quantification. A score from 0 to 4 according to Rassler et al. (2005) was used to assess the degree of lung injury. RESULTS: All animals developed histological signs of heart failure as indicated by island-like, patchy fibrosis of the heart. Planimetric quantification (PSR stain) of the heart revealed a significant increase of the total amount of fibrosis from 8+/-2% (base) to 21+/-4% (3 months) (P<0.05), which was distributed homogeneously throughout the left ventricle (20+/-3% left ventricular [LV] anterior wall, 21+/-4% LV posterior wall, 20+/-4% septum). Histologic analysis of the lung demonstrated a moderate degree of interstitial edema and pronounced peribronchial processes of inflammation with beginning proliferation of fibrotic tissue. Liver tissue showed histological changes in terms of pericentral adiposis as sign of hypoxia in course of lacking perfusion. Signs of liver congestion could be detected histological in form of central-venous accumulation of erythrocytes and dissolution of liver tissue in proximity of the central veins. Kidney preparations illustrated loss of endothelial function and vascular occlusions, caused by microspheres, with decline of renal parenchyma particularly of the tubules. CONCLUSION: Multiple sequential intracoronary microembolization can effectively induce myocardial dysfunction with histological signs of chronic ischemic cardiomyopathy and pathological changes of lung, liver and kidney, which can directly be coursed by chronic heart failure. Thus, the present model may be suitable in experimental work on heart failure and LV assist devices, e.g. for studying the impact of mechanical unloading, mechanisms of recovery and reverse remodeling.


Asunto(s)
Enfermedad de la Arteria Coronaria/complicaciones , Embolia/complicaciones , Insuficiencia Cardíaca/etiología , Miocardio/patología , Animales , Enfermedad Crónica , Enfermedad de la Arteria Coronaria/etiología , Enfermedad de la Arteria Coronaria/patología , Enfermedad de la Arteria Coronaria/fisiopatología , Modelos Animales de Enfermedad , Embolia/etiología , Embolia/patología , Embolia/fisiopatología , Insuficiencia Cardíaca/patología , Insuficiencia Cardíaca/fisiopatología , Inyecciones Intraarteriales , Riñón/patología , Hígado/patología , Pulmón/patología , Microesferas , Poliestirenos/administración & dosificación , Reproducibilidad de los Resultados , Ovinos
15.
Radiat Environ Biophys ; 47(3): 389-97, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18493784

RESUMEN

In a previous publication, we were able to show that irradiation of Kupffer cells, the liver resident macrophages, leads to an increased TNF-alpha concentration in the culture medium. The pathomechanisms underlying this phenomenon, however, remained to be elucidated. Here, we show that following irradiation of Kupffer cells, the apoptosis rate increased drastically within 48 h. At the same time, the total TNF-alpha concentration in cell lysates of Kupffer cells attached to the culture plate decreased. However, normalization of the TNF-alpha concentration with respect to cell number revealed that TNF-alpha concentration per attached cell remained constant during the observation period. Western blot analysis showed that heat shock protein 27 (Hsp27) is strongly downregulated and bax is upregulated in irradiated Kupffer cells as compared to sham-irradiated cells. Overexpression of Hsp27 in Kupffer cells was shown to prevent the effect of irradiation on bax expression, apoptosis and, at the same time, on increase of TNF-alpha concentration in the Kupffer cell medium. We conclude that irradiation of Kupffer cells leads to apoptosis because of downregulation of Hsp27 and consecutive upregulation of bax expression. Furthermore, we suggest that apoptosis of Kupffer cells leads to an increase of TNF-alpha concentration in the culture medium which may be due to cell death rather than active release or synthesis.


Asunto(s)
Apoptosis/efectos de la radiación , Proteínas de Choque Térmico/fisiología , Macrófagos del Hígado/efectos de la radiación , Proteínas de Neoplasias/fisiología , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Caspasas/metabolismo , Supervivencia Celular/efectos de la radiación , Células Cultivadas , Proteínas de Choque Térmico HSP27 , Proteínas de Choque Térmico/análisis , Masculino , Proteínas de Neoplasias/análisis , Ratas , Ratas Wistar , Proteína X Asociada a bcl-2/análisis
16.
J Pathol ; 215(3): 253-62, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18438954

RESUMEN

Loss of chromosome 9p is a reliable predictor of malignant behaviour in gastrointestinal stromal tumours (GISTs). p16INK4A located at 9p21 inhibits the CDK4/6/cyclin D complex from phosphorylating RB. Phosphorylation of RB through CDK4/6/cyclin D in early G(1) phase frees the transcription factor E2F1 from RB and enables mRNA transcription of genes essential for G(1)/S phase transition. This study aims to determine the impact of 9p loss on mRNA and protein expression of p16INK4A and further key cell cycle regulators in the different phases of the cell cycle. Sixty primary GISTs previously characterized for 9p loss by comparative genomic hybridization were analysed for mRNA expression of p16INK4A, p15INK4B, CDK4, CDK6, cyclin D, p21CIP1p27KIP1, CDK2, cyclin E, cyclin B, RB and E2F1, using quantitative RT-PCR. The protein expression of CDK6, CDK2, p21CIP1, p27KIP1 and phosphorylated RB (S807/S811) was evaluated using protein arrays as a novel and highly sensitive platform for profiling of protein abundance and protein phosphorylation. In parallel, the nuclear percentages of immunohistochemical staining for p16INK4A, cyclin D, E2F1 and RB were quantified on a tissue microarray. GISTs with 9p loss had significantly higher proliferation rates, higher metastatic behaviour and shorter disease-free survival. On the molecular level, GISTs with 9p loss had a significantly reduced mRNA as well as nuclear protein expression of p16INK4A. RB was significantly more phosphorylated in these tumours, together with increased mRNA expression and nuclear staining for E2F1. Furthermore, GISTs with 9p loss had up-regulation of the late G1/S phase promoters CDK2 and cyclin E. We conclude that loss of 9p accompanied by early G1 phase inhibitor p16(INK4A) down-regulation in GISTs facilitates phosphorylation of RB, enabling E2F1-dependent transcription of genes essential for late G1/S phase transition. This study provides a possible basis for the accelerated proliferation and particularly malignant behaviour in GISTs with 9p loss.


Asunto(s)
Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Tumores del Estroma Gastrointestinal/genética , Eliminación de Gen , Regulación Neoplásica de la Expresión Génica , Proteínas de Ciclo Celular/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina/análisis , Progresión de la Enfermedad , Factor de Transcripción E2F1/análisis , Factor de Transcripción E2F1/metabolismo , Expresión Génica , Perfilación de la Expresión Génica , Genes de Retinoblastoma , Humanos , Inmunohistoquímica , Análisis de Secuencia por Matrices de Oligonucleótidos , Modelos de Riesgos Proporcionales , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos
17.
Internist (Berl) ; 48(8): 863-9, 2007 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-17605114

RESUMEN

A 22 year old female patient presented with fever, night sweats, weight loss and hepatomegaly associated with elevated inflammatory parameters and liver enzymes. Computer tomography revealed a mass located between the inferior vena cava and the psoas muscle as well as enlarged celiac, retroperitoneal and retrocaval lymph nodes. Biopsies of the retrocaval mass led to the diagnosis of retroperitoneal fibrosis. Within a few days of treatment with corticosteroids clinical presentation improved and imaging studies detected complete regression of the retrocaval mass after 6 months.


Asunto(s)
Fiebre de Origen Desconocido/etiología , Hepatomegalia/etiología , Fibrosis Retroperitoneal/diagnóstico , Sudoración , Pérdida de Peso , Adulto , Biopsia , Diagnóstico Diferencial , Diagnóstico por Imagen , Femenino , Fiebre de Origen Desconocido/patología , Hepatomegalia/patología , Humanos , Fibrosis Retroperitoneal/patología , Espacio Retroperitoneal/patología
19.
Z Gastroenterol ; 45(1): 51-62, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17236121

RESUMEN

The liver plays a unique role in controlling carbohydrate metabolism by maintaining glucose concentrations in a normal range. This is achieved by a tightly regulated system of enzymes and kinases regulating either glucose breakdown or synthesis in hepatocytes. This process is under the control of glucoregulatory mediators among which insulin plays a key role. In type 2 diabetes, as well as in liver disease, alterations in hepatic glucose metabolism like an increased post-absorptive glucose production together with diminished glucose uptake following carbohydrate ingestion occur, implying insulin resistance as a central pathological principle. Knowledge of the processes involved in maintaining glucose homeostasis as well as insulin resistance is a prerequisite to develop new therapeutic approaches in diabetes as well as in liver disease. In the recent years, genetically-altered mouse models that have helped to identify enzymes, transcription factors and mediators that are essential for maintaining glucose homeostasis in the liver and provide a valuable tool to study carbohydrate metabolism in liver disease. In this current review, genetically manipulated animals either overexpressing or lacking key gluconeogenic enzymes, hepatic transcription factors, IGF-1, hepatic insulin receptors, adipokines and hepatitis C core antigen will be discussed in the context of human disease.


Asunto(s)
Metabolismo de los Hidratos de Carbono , Carbohidratos de la Dieta/metabolismo , Glucosa/metabolismo , Resistencia a la Insulina , Hepatopatías/metabolismo , Hígado/metabolismo , Modelos Biológicos , Animales , Humanos
20.
Z Gastroenterol ; 45(1): 77-86, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17236124

RESUMEN

Liver fibrosis is defined as an excessive deposition of extracellular matrix. It is the main complication of chronic liver damage and its endpoint, the liver cirrhosis, is responsible for impressive morbidity and mortality. The accumulation of extracellular matrix proteins in liver fibrosis and cirrhosis is due to different cell types which acquire a myofibroblastic phenotype--the hepatic stellate cells, located in the space of Disse, portal fibroblasts as well as myofibroblasts of the portal and pericentral areas. Further studies also suggest an impressive role of bone marrow-derived myofibroblasts. Differences have been reported between the two cell populations with respect to myofibroblastic differentiation, activation and "deactivation", proliferation and apoptosis. However, in most cases additional confirmation may be required; thus the biological and biochemical characterization of these cells, their interactions with inflammatory cells and the cytokine environment leading to their activation or cell death are essential to understand the mechanisms underlying the progressive development of excessive scarring in the liver as well as the ability of the liver for tissue repair and regeneration. All this information is required to estimate the value of already suggested possible treatments to specifically and efficiently target the cells responsible for the development of liver fibrosis/cirrhosis and as well as for liver regeneration.


Asunto(s)
Citocinas/inmunología , Hepatitis/inmunología , Hepatitis/patología , Factores Inmunológicos/inmunología , Cirrosis Hepática/inmunología , Cirrosis Hepática/patología , Regeneración Hepática/inmunología , Animales , Comunicación Celular/inmunología , Hepatocitos/inmunología , Humanos , Modelos Inmunológicos , Linfocitos T/inmunología
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