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1.
J Viral Hepat ; 23(5): 375-86, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26833585

RESUMEN

The interferon-stimulated gene 15 (ISG15) plays an important role in the pathogenesis of hepatitis C virus (HCV) infection. ISG15-regulated proteins have previously been identified that putatively affect this proviral interaction. The present observational study aimed to elucidate the relation between ISG15 and these host factors during HCV infection. Transcriptomic and proteomic analyses were performed using liver samples of HCV-infected (n = 54) and uninfected (n = 10) or HBV-infected controls (n = 23). Primary human hepatocytes (PHH) were treated with Toll-like receptor ligands, interferons and kinase inhibitors. Expression of ISG15 and proteasome subunit alpha type-6 (PSMA6) was suppressed in subgenomic HCV replicon cell lines using specific siRNAs. Comparison of hepatic expression patterns revealed significantly increased signals for ISG15, IFIT1, HNRNPK and PSMA6 on the protein level as well as ISG15, IFIT1 and PSMA6 on the mRNA level in HCV-infected patients. In contrast to interferon-stimulated genes, PSMA6 expression occurred independent of HCV load and genotype. In PHH, the expression of ISG15 and PSMA6 was distinctly induced by poly(I:C), depending on IRF3 activation or PI3K/AKT signalling, respectively. Suppression of PSMA6 in HCV replicon cells led to significant induction of ISG15 expression, thus combined knock-down of both genes abrogated the antiviral effect induced by the separate suppression of ISG15. These data indicate that hepatic expression of PSMA6, which is upregulated during viral hepatitis, likely depends on TLR3 activation. PSMA6 affects the expression of immunoregulatory ISG15, a proviral factor in the pathogenesis of HCV infection. Therefore, the proteasome might be involved in the enigmatic interaction between ISG15 and HCV.


Asunto(s)
Citocinas/biosíntesis , Expresión Génica , Hepatitis C/patología , Complejo de la Endopetidasa Proteasomal/biosíntesis , Ubiquitinas/biosíntesis , Adulto , Biopsia , Células Cultivadas , Femenino , Perfilación de la Expresión Génica , Hepatocitos/fisiología , Humanos , Masculino , Persona de Mediana Edad , Proteoma/análisis
2.
J AIDS Clin Res ; 7(12)2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28255515

RESUMEN

OBJECTIVE: The spectrum of neuropsychiatric illness (NI) associated with the Human Immunodeficiency Virus (HIV) and/or the Hepatitis C Virus (HCV) is far reaching and significantly impacts the clinical presentation and outcome of infected persons; however, the etiological and pathophysiological background remains partially understood. The present work was aimed to investigate the potential significance of formin binding protein 1 (FNBP-1)-dependent pathways in NI-pathogenesis by elaborating on previous microarray-based research in HIV and/or HCV-infected patients receiving interferon-α (IFN-α) immunotherapy via a rigorous data mining procedure. METHODS: Using microarray data of peripheral whole blood (PB) samples obtained from HCV mono-infected persons (n=25, Affymetrix® HG-U133A_2) 12 h before and after the 1st dose of pegylated IFN-α (PegIFN-α), we re-applied the same analytical algorithm that we had developed and published in an earlier study with HIV/HCV co-infected subjects (N=28, Affymetrix® HG-U133A), in order to evaluate reproducibility of potential NI-related molecular findings in an independent cohort. RESULTS: Among 28 gene expression profiles (HIV/HCV: N=9 vs. HCV: N=19) selected by applying different thresholds (a Mean Fold Difference value (MFD) in gene expression of ≥ 0.38 (log2) and/or P value from <0.05 to ≤ 0.1) FNBP-1 was identified as the only overlapping marker, which also exhibited a consistent upregulation in association with the development of NI in both cohorts. Previous functional annotation analysis had classified FNBP-1 as molecule with significant enrichment in various brain tissues (P<0.01). CONCLUSION: Our current findings are strongly arguing for intensifying research into the FNBP-1-related mechanisms that may be conferring risk for or resistance to HIV- and/or HCV-related NI.

3.
Int J Med Microbiol ; 305(7): 627-35, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26384868

RESUMEN

HCV RNA assays are of central importance for virological diagnostics and for clinical planning and monitoring of an antiviral combination treatment of chronic HCV infections. The objective of the pre-market evaluation of the VERSANT HCV RNA 1.0 Assay (kPCR) was to collect analytical performance data for this new method of HCV RNA quantification and to compare them with the high standards that exist in this context. The assay exhibited a specificity of 100%. The mean intra- and inter-assay imprecision was 14.1% and 14.6%, respectively. The detection limit was determined to be 16IU/ml (95% confidence interval: 11.9-30.6IU/ml) and consequently corresponded to the manufacturer's claims (i.e. 15IU/ml). The test exhibited linearity for all HCV genotypes in a broad range from 15 to 10(8)IU HCV RNA/ml. Hence, the kPCR assay in general is well suitable for HCV RNA determinations in clinical practice. However, in a methodological comparison, a considerable under-quantification of the concentrations of HCV genotype 2 and 3 isolates was detected. Provided that the assay's manufacturer will quickly remedy this shortcoming, the VERSANT HCV RNA 1.0 (kPCR) can be called a completely reliable technique for HCV RNA quantification in routine virological diagnostics.


Asunto(s)
Monitoreo de Drogas/métodos , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/diagnóstico , ARN Viral/sangre , Carga Viral/métodos , Adolescente , Adulto , Anciano , Niño , Femenino , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Adulto Joven
4.
Z Gastroenterol ; 52(6): 564-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24905108

RESUMEN

BACKGROUND: More recently, autoimmune pancreatitis (AIP) in association with IgG4-positive cholangitis (IAC) has been recognised as a new and challenging entity. Currently, initiation of high dose steroids (e.g., prednisolone 0.5 - 1 mg/kg/day) followed by a steroid dose taper in combination with purine antagonists (e.g., azathioprine or 6-mercaptopurine) after resolution has been recommended as standard therapy. CASE REPORT: A 68-year-old male patient was referred to our institution in February 2012 for therapy evaluation of a steroid-dependent course of autoimmune pancreatitis type 1 with IgG4-associated cholangitis. Since the first diagnosis in March 2011, the patient was treated with high-dose steroids with good response. Whenever steroids were tapered down to a daily dose <20 mg, cholestatic liver enzymes increased dramatically despite concurrent immunosuppressive therapy primarily with azathioprine and 6-MP thereafter. Therefore, we restarted steroid therapy (1 mg/kg/day) in combination with tacrolimus achieving a target level of 5 - 7 ng/mL. During the down-tapering phase, follow-up examinations presented a patient in good general condition without jaundice. Moreover, liver and pancreatic enzymes and also immunoglobulins returned to normal values without any evidence of relapse up today (66 weeks). CONCLUSION: In this case, the combination of steroids with tacrolimus seems to be a reasonable alternative in a patient with steroid-dependent and thiopurine-refractory autoimmune pancreatitis with IgG4-associated cholangitis. To date, this is the first description of such a therapeutic approach for this entity.


Asunto(s)
Colangitis/tratamiento farmacológico , Colangitis/inmunología , Inmunoglobulina G/inmunología , Pancreatitis/tratamiento farmacológico , Pancreatitis/inmunología , Esteroides/administración & dosificación , Tacrolimus/administración & dosificación , Anciano , Azatioprina/administración & dosificación , Colangitis/diagnóstico , Quimioterapia Combinada/métodos , Humanos , Inmunosupresores/administración & dosificación , Masculino , Pancreatitis/diagnóstico , Insuficiencia del Tratamiento
5.
J Viral Hepat ; 21(7): 480-90, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24750363

RESUMEN

Chronic hepatitis C infection is associated with increased expression of interferon-sensitive genes (ISGs) in the liver, which is, paradoxically, correlated with the nonresponse to interferon (IFN)-based therapies. In the present study PHHs were isolated from HCV-infected or uninfected patients and stimulated with the TLR1-9 ligands for 6-24 h. Expression of cytokines and ISGs was determined by ELISA and qRT-PCR. A comparative analysis was performed for TLR3 signalling, which was also correlated with single nucleotide polymorphisms (SNPs) related to HCV pathogenesis. TLR-activated PHHs produced pro-inflammatory and anti-inflammatory cytokines, whereas IFNs were exclusively induced by TLR3 stimulation. Here, IL-29 and IL-28A were significantly highly expressed than IFN-α and IFN-ß. TLR3-induced IFN response was enhanced in hepatocytes isolated from patients with HCV infection. This hyper-responsiveness could be mimicked in naïve PHHs consistently stimulated with low dose of poly I:C, but not Guardiquimod. The higher responsiveness in PHH isolated from HCV-infected patients could be partially explained by higher frequencies of unfavourable SNP alleles of different SNPs associated with HCV progression and treatment outcome. These data suggest that durable activation of TLR3 but not TLR7, by low doses of viral replicative intermediates, increases the sensitivity to viral invasion. These findings shed new light on the relevance of TLR3 in the pathogenesis of HCV and may provide a possible explanation for the increased ISG expression during chronic HCV infection, the so-called IFN paradox.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Hepatocitos/efectos de los fármacos , Hepatocitos/inmunología , Poli I-C/farmacología , Receptor Toll-Like 3/inmunología , Citocinas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Perfilación de la Expresión Génica , Humanos
6.
Clin Radiol ; 69(5): e216-22, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24581959

RESUMEN

AIM: To assess the effect of gastroduodenal artery (GDA) occlusion prior to selective internal radiation therapy (SIRT) with regards to arterial hepato-intestinal collateralization (HIC). MATERIALS AND METHODS: Six hundred and six patients were scheduled for SIRT between 2006 and 2012 at University Hospital Essen, Germany. Digital subtraction angiography (DSA) followed by administration of 99m-technetium labelled human serum albumin microspheres ((99m)Tc-HSAM) and single-photon emission computed tomography combined with computed tomography (SPECT/CT) was initially performed. Depending on vascular anatomy and hepatic tumour load, GDA coil embolization was considered. In subsequent (99m)Tc-HSAM rescans or therapeutic DSA, HIC and its consequences for SIRT were analysed. RESULTS: The GDA was occluded in 86 of 606 patients (14%). Twenty-two of these 86 patients did not undergo SIRT due to the patients' clinical status or SIRT contraindications. In 28 of the remaining 64 patients, newly apparent or reopened HIC were seen either at the site of the proximal GDA (n = 21) or in the periphery of the hepatic arteries (n = 7). In 25 of these 28 patients, the HIC could be occluded or the catheter position could be changed achieving a safe (90)Y application. However, due to the newly visible HIC in three of 28 patients, SIRT was regarded as unsafe and was abandoned. CONCLUSION: Coil embolization of the GDA may induce arterial hepato-intestinal collaterals. Although most of these collaterals do not impede (90)Y administration, SIRT may become unfeasible in specific occasions. Hence, segmental or lobar SIRT instead of a whole-liver approach with coiling of the GDA is recommended.


Asunto(s)
Angiografía de Substracción Digital , Embolización Terapéutica/métodos , Arteria Hepática/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Radiofármacos , Agregado de Albúmina Marcado con Tecnecio Tc 99m , Tomografía Computarizada de Emisión de Fotón Único , Anciano , Duodeno/irrigación sanguínea , Femenino , Alemania/epidemiología , Arteria Hepática/patología , Humanos , Hígado/diagnóstico por imagen , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Selección de Paciente , Dosis de Radiación , Tomografía Computarizada de Emisión de Fotón Único/métodos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Carga Tumoral
7.
J Viral Hepat ; 21(12): 860-72, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24498958

RESUMEN

It has been recently shown that Toll-like receptor (TLR) signalling in murine nonparenchymal liver cells (NPCs) is suppressed in the presence of Hepatitis B virus surface antigen (HBsAg). It is not clear, however, whether this is also relevant for the adaptive immune responses and how this effect is mediated. Peripheral blood mononuclear cells (PBMCs) from Hepatitis B virus (HBV) patients and controls were stimulated by TLR ligands in the absence or presence of autologous serum. Interestingly, TLR-mediated cytokine expression (Interleukin-6 and -10) as well as TLR3-induced interferon (IFN) expression in PBMCs of HBV patients was significantly higher than in the healthy volunteers, showing a negative correlation with the levels of HBsAg. In addition, TLR3-mediated IFN-γ production was inhibited in the presence of HBV-containing serum. To mechanistically analyse this observation, murine Kupffer cells (KCs) and sinusoidal endothelial cells (LSECs) were stimulated with TLR3 ligands in the presence or absence of HBsAg. Mixed lymphocyte reactions were performed to study T-cell activation induced by TLR-stimulated NPCs. Gene expression of cytokines and TLR3 was analysed by quantitative rt-PCR, and activation of transcription factors was assessed by Western blot or reporter gene assays. TLR-induced expression of interferon γ, interferon sensitive genes and proinflammatory cytokines in murine KCs and LSECs was efficiently suppressed in the presence of HBsAg, whereas the expression of anti-inflammatory cytokines was enhanced. Activation of NFκB, IRF-3 and MAPKs in these liver cells was potently suppressed by HBsAg. T-cell activation mediated through TLR3-stimulated KCs or LSECs was suppressed by HBsAg which could be reverted by anti-IL-10 antibodies. These findings may, at least in part, explain how HBV evades innate and adaptive immune responses to maintain a persistent infection.


Asunto(s)
Citocinas/metabolismo , Antígenos de Superficie de la Hepatitis B/análisis , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/virología , Receptores Toll-Like/inmunología , Adulto , Animales , Western Blotting , Células Endoteliales/inmunología , Femenino , Perfilación de la Expresión Génica , Humanos , Macrófagos del Hígado/inmunología , Leucocitos Mononucleares/inmunología , Masculino , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Reacción en Cadena en Tiempo Real de la Polimerasa
8.
J Viral Hepat ; 21(2): 99-110, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24383923

RESUMEN

The hepatitis C virus (HCV) establishes persistent infections despite strong activation of the innate immune system through TLR3 and other sensors. Therefore, we analysed regulatory mechanisms of TLR3-induced immune responses in nonparenchymal liver cells (NPCs). Effects of Interleukin-10 (IL-10), transforming growth factor beta (TGF-ß) and immunoregulatory miR-155 on poly I:C-activated murine (C57BL/6) Kupffer cells (KC) and sinusoidal endothelial cells (LSEC) were assessed in vitro. NPCs were assayed for inflammatory and antiviral cytokines and T-cell (Balb/c)-activating factors. Gene expression of miR-155, IL-10, TGF-ß and interferon sensitive genes (ISGs) in biopsies of patients with HCV was determined by qrt-PCR. TLR3-induced antiviral activity in murine NPCs was potently suppressed by IL-10 and TGF-ß which correlated with decreased TLR3 expression and inhibition of NF-κB and IRF-3 activation. T-cell activation, induced by TLR3-activated NPCs, was also suppressed by IL-10 and TGF-ß, which was associated with a down-regulation of CD80 and CD86. Pretreatment with IL-10 or TGF-ß suppressed TLR3-induced miR-155 expression, which itself positively regulated poly I:C-mediated immune responses, thus counteracting IL-10 or TGF-ß-induced immunosuppression. In addition, hepatic expression of miR-155 was elevated in chronically infected patients with HCV, was associated with an IL-28B SNP (rs12979860) and was inversely correlated with HCV serum load and ISG expression levels. As miR-155 is a key regulator of anti-inflammatory mechanisms that control innate and adaptive hepatic immune responses during HCV infection, miR-155 based therapies may represent a novel mechanism to control HCV in the future.


Asunto(s)
Hepacivirus/inmunología , Hepatitis C Crónica/inmunología , Hígado/patología , MicroARNs/metabolismo , Receptor Toll-Like 3/inmunología , Animales , Células Endoteliales/inmunología , Perfilación de la Expresión Génica , Humanos , Macrófagos del Hígado/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL
9.
Clin Radiol ; 69(2): 172-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24209871

RESUMEN

AIM: To assess volume changes of treated and non-treated liver segments after selective internal radiation therapy (SIRT) in patients with hepatocellular carcinoma (HCC) and compromised hepatic function due to cirrhosis over a time course of 12 months after SIRT. MATERIALS AND METHODS: All patients underwent SIRT of the right liver lobe with yttrium 90 (Y-90). Absolute volumes of the right liver lobe (RLV) and left liver lobe (LLV) were assessed using computed tomography (CT) before and 1, 3, 6, 9, and 12 months after SIRT. Changes at follow-up relative to baseline volumes were analysed ("normalized" volumes). Furthermore, the relative volume of the LLV [LLV/(RLV + LLV)] was calculated ("relative" volumes). For statistical analysis p < 0.05 was considered statistically significant. RESULTS: Forty-five HCC patients (36 men, nine women, mean age 71.9 years, range 55-90 years) were studied. The mean baseline RLV and LLV reached 1116 ml [95% confidence intervals (CI): 1006-1226 ml] and 601 ml (95% CI: 514-688 ml), respectively. At 6 months following radioembolization, the LLV increased by 30.8% (RLV -33.9%), with the relative LLV increasing from 35% (pre-radioembolization) to 50.5%. RLV further decreased and LLV increased 12 months after SIRT (nRLV -44.9%, nLLV +40.1%, relative LLV 56.5%). All changes were significant. CONCLUSION: Constraints of liver function after radioembolization of one liver lobe can be partially compensated through hypertrophy of the contralateral lobe. The rate of volumetric changes is the highest in the first 6 months following radioembolization. The present data can also be the basis to propagate radiation lobectomy for selected patients, simultaneously providing tumour control and future remnant liver hypertrophy before curative hemihepatectomy.


Asunto(s)
Carcinoma Hepatocelular/radioterapia , Embolización Terapéutica/métodos , Neoplasias Hepáticas/radioterapia , Hígado/patología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Hígado/efectos de la radiación , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Radioisótopos de Itrio/uso terapéutico
10.
Br J Pharmacol ; 168(5): 1048-58, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23072338

RESUMEN

During most viral infections, the immediate host response is characterized by an induction of type I IFN. These cytokines have various biological activities, including anti-viral, anti-proliferative and immunomodulatory effects. After induction, they bind to their IFN-α/ß receptor, which leads to downstream signalling resulting in the expression of numerous different IFN-stimulated genes. These genes encode anti-viral proteins that directly inhibit viral replication as well as modulate immune function. Thus, the induction of type I IFN is a very powerful tool for the host to fight virus infections. Many viruses evade this response by various strategies like the direct suppression of IFN induction or inhibition of the IFN signalling pathway. Therefore, the therapeutic application of exogenous type I IFN or molecules that induce strong IFN responses should be of great potential for future immunotherapies against viral infections. Type I IFN is currently used as a treatment in chronic hepatitis B and C virus infection, but as yet is not widely utilized for other viral infections. One reason for this restricted clinical use is that type I IFN belongs to a multigene family that includes 13 different IFN-α subtypes and IFN-ß, whose individual anti-viral and immunomodulatory properties have so far not been investigated in detail to improve IFN therapy against viral infections in humans. In this review, we summarize the recent achievements in defining the distinct biological functions of type I IFN subtypes in cell culture and in animal models of viral infection as well as their clinical usage in chronic hepatitis virus infections.


Asunto(s)
Antivirales/uso terapéutico , Interferón Tipo I/uso terapéutico , Subunidades de Proteína/uso terapéutico , Virosis/tratamiento farmacológico , Animales , Antivirales/farmacología , Humanos , Interferón Tipo I/farmacología , Interferón Tipo I/fisiología , Subunidades de Proteína/farmacología
11.
J Viral Hepat ; 19(2): 128-37, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22239502

RESUMEN

Mechanisms causing liver fibrosis during chronic hepatitis C virus infection (cHCV) are not sufficiently understood. This study was aimed to identify biomarkers for early fibrosis (EF) and to investigate their potential role in cHCV-related fibrogenesis. To this end, peripheral whole blood (PB) samples from 36 patients with cHCV recruited from two independent cohorts were subjected to microarray analysis 12 h before initiation of peginterferon-alpha (Peg-IFN-α) and ribavirin therapy. Liver biopsies were evaluated using the Batts-Ludwig staging (BL-S) classification system for fibrosis. We showed that gene expression profiles (N = 8) distinguished between EF (BL-S: 0,1) and late fibrosis (LF; BL-S: 2,3,4) with 88.9% accuracy. Fibrosis-related functional annotations for chemokine-'C-C-motif'' ligand 5 (CCL5) provided foundation for focused investigation, and qRT-PCR confirmed that CCL5 mRNA levels (PB) reliably discriminate EF from LF (accuracy: 86.7%). Positive correlations (P < 0.05) with CCL5 mRNA levels and EF discovered gene expression profiles (PB) reflecting stable expression of IFN-α receptor 1, negative regulation of the MyD88-dependent toll-like receptor (TLR) pathway and decreased expression of TLR3 in vivo. Remarkably, Peg-IFN-α suppressed CCL5 mRNA levels (PB) in EF in vivo. These findings along with results from parallel in vitro investigation into the effect of IFN-α or poly I:C (TLR3-agonist) on CCL5 gene expression in hepatic stellate cells (HSC) attest to the multi-site involvement of these pathways in regulating fibrogenesis. In conclusion, we identified novel, reliable biomarkers for EF and exposed functional properties of the molecular network regulating CCL5 biosynthesis in peripheral or hepatic cell types with key roles in cHCV-related liver and/or immune pathogenesis.


Asunto(s)
Biomarcadores , Quimiocina CCL5/biosíntesis , Hepatitis C Crónica/complicaciones , Interferón-alfa/inmunología , Cirrosis Hepática/diagnóstico , ARN Mensajero/biosíntesis , Receptor Toll-Like 3/inmunología , Antivirales/administración & dosificación , Antivirales/inmunología , Biopsia , Perfilación de la Expresión Génica , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Factores Inmunológicos/administración & dosificación , Factores Inmunológicos/inmunología , Interferón-alfa/administración & dosificación , Leucocitos/inmunología , Hígado/patología , Cirrosis Hepática/patología , Análisis por Micromatrices , Reacción en Cadena en Tiempo Real de la Polimerasa , Ribavirina/administración & dosificación , Transducción de Señal
12.
Rofo ; 183(11): 1058-64, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21959887

RESUMEN

PURPOSE: Radioembolization using 90yttrium is an emerging therapy option for unresectable liver malignancies. In order to reduce the number of yttrium injections, endovascular occlusion of a segmental hepatic artery has been proposed. The aim of this study was to assess whether sufficient vascular redistribution of the occluded liver segments through intrahepatic collaterals can be observed. MATERIALS AND METHODS: 27 patients with hepatocellular carcinoma (n = 16) or hepatic metastases (n = 11) were studied. Hepatic angiography was performed on average 16 days prior to radioembolization. The segment II/III artery (n = 9) or the segment IV artery (n = 18) was occluded using coils. Technectium-99m-labeled macroaggregated albumin (99mTc-MAA) was injected into the right and the remaining part of the left hepatic artery in order to identify any hepatic volume not included in the perfused area. Patients underwent a SPECT/CT on average 1 h after the 99mTc-MAA injection. Two radiologists evaluated the SPECT/CT scans regarding the presence of non-perfused hepatic segments. Furthermore, hepatic perfusion was assessed by digital subtraction angiography (DSA) on the day of radioembolization. RESULTS: In 16/27 patients (59%) a perfusion of the occluded liver segment was visible on the SPECT/CT scan. In 8/11 patients without flow redistribution at the time of the SPECT/CT, perfusion of the occluded segment through hepatic collaterals was observed during angiography prior to radioembolization. Hence, flow redistribution was eventually found in 24/27 patients (89%). CONCLUSION: Flow redistribution after the occlusion of intrahepatic arteries prior to radioembolization can be successfully induced in the majority of patients with anatomical variants of the hepatic arteries.


Asunto(s)
Carcinoma Hepatocelular/irrigación sanguínea , Carcinoma Hepatocelular/radioterapia , Embolización Terapéutica/métodos , Arteria Hepática/efectos de la radiación , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundario , Neovascularización Patológica/radioterapia , Tomografía Computarizada de Emisión de Fotón Único , Tomografía Computarizada por Rayos X , Radioisótopos de Itrio/administración & dosificación , Anciano , Anciano de 80 o más Años , Angiografía de Substracción Digital , Neoplasias de la Mama/irrigación sanguínea , Neoplasias de la Mama/radioterapia , Circulación Colateral/fisiología , Neoplasias Colorrectales/irrigación sanguínea , Neoplasias Colorrectales/radioterapia , Femenino , Humanos , Masculino , Neoplasias Primarias Desconocidas/irrigación sanguínea , Neoplasias Primarias Desconocidas/radioterapia
13.
Eur Surg Res ; 39(1): 58-63, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17213727

RESUMEN

BACKGROUND: Tri-iodothyronine (T3) has been shown to be a hepatic mitogen. We investigated whether exogenous application of T3 improves liver regeneration after 70% partial hepatectomy (PH) and confers a survival advantage after 90% subtotal hepatectomy (SH) in rats and whether this is associated with the stimulation of angiogenesis. METHODS: Rats were subjected to PH or SH 10 days after injection of a single dose of T3. Liver body weight ratio (LBR), hepatic proliferation (Ki-67), biochemical markers as well as vascular endothelial growth factor (VEGF) expression were assessed by immunohistochemistry. Gene expression of pathogenic relevant genes was determined by customized cDNA arrays and quantitative RT-PCR. RESULTS: T3-treated rats showed an increased LBR and Ki-67 index after PH and SH, which reached statistical significance compared to placebo-treated rats (p < 0.05). On the transcriptional level, T3-treated rats had an increased expression of VEGF as demonstrated by immunohistochemistry, which was associated with a higher expression of its receptor Flt-1. CONCLUSIONS: Exogenous administration of T3 ameliorates liver regeneration after 70% PH and 90% SH, possibly due to stimulation of angiogenesis. Therefore, its clinical use might be of interest due to its excellent general practicability.


Asunto(s)
Hepatectomía , Regeneración Hepática/efectos de los fármacos , Trasplante de Hígado , Triyodotironina/farmacología , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , División Celular/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Glutamato Deshidrogenasa/sangre , Antígeno Ki-67/metabolismo , Hígado/citología , Hígado/cirugía , Regeneración Hepática/genética , Donadores Vivos , Masculino , Análisis de Secuencia por Matrices de Oligonucleótidos , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Wistar , Tasa de Supervivencia , Factor A de Crecimiento Endotelial Vascular/metabolismo
15.
EMBO J ; 20(19): 5431-42, 2001 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-11574475

RESUMEN

A tripartite receptor comprising the external region of the erythropoietin (Epo) receptor, the transmembrane and JAK-binding domains of the gp130 subunit of the interleukin-6 (IL-6) receptor, and a seven amino acid STAT1 recruitment motif (Y440) from the interferon (IFN)-gamma receptor, efficiently mediates an IFN-gamma-like response. An analogous completely foreign chimeric receptor in which the Y440 motif is replaced with the Y905 motif from gp130 also mediates an IFN-gamma-like response, but less efficiently. The IFNGR1 signal-transducing subunit of the IFN-gamma receptor is tyrosine phosphorylated through the chimeric receptors and the endogenous IL-6 and OSM receptors. Cross phosphorylation of IFNGR1 is not, however, required for the IFN-gamma-like response through the chimeric receptors, nor does it mediate an IFN-gamma-like response to IL-6 or OSM. The data argue strongly for modular JAK/STAT signalling and against any rigid structural organization for the "pathways" involved. They emphasize the likely high degree of overlap between the signals generated from disparate JAK-receptor complexes and show that relatively minor changes in such complexes can profoundly affect the response.


Asunto(s)
Interferón gamma/metabolismo , Proteínas Nucleares , Receptores Inmunológicos/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica , Antígenos de Histocompatibilidad Clase II/biosíntesis , Humanos , Receptor de Interferón alfa y beta , Receptores de Eritropoyetina/genética , Receptores de Eritropoyetina/metabolismo , Receptores Inmunológicos/genética , Receptores de Interferón/genética , Receptores de Interferón/metabolismo , Receptores de Interleucina-6/genética , Receptores de Interleucina-6/metabolismo , Factor de Transcripción STAT1 , Transducción de Señal , Transactivadores/biosíntesis , Transactivadores/metabolismo , Receptor de Interferón gamma
16.
Scand J Immunol ; 54(4): 396-403, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11555406

RESUMEN

The aim of this study was to characterize the functional relevance of the transcription factor NF-kappaB in the pathogenesis of septic shock. BALB/c mice were infected with two wild-type (WT 1, WT 2) strains of S. typhimurium that induce NF-kappaB or an escape variant that lacks this ability (P21) at a dose of 1 x 109/animal, respectively. Furthermore, wild-type infected mice were treated with antisense oligonucleotides directed against NF-kappaB 24 h before and 3 or 6 h after infection, while mismatched oligonucleotides were used as controls. Subsequently, the clinical course, histological and immunological alterations were monitored. Infection with WT 1 and WT 2 strains led to lethal septic shock within 24-36 h. In contrast, infection with the P21 variant was not followed by fulminant septic shock. Treatment with specific antisense oligonucleotides against the p65 subunit of NF-kappaB 24 h before infection prevented the development of fulminant, lethal septic shock and was associated with a significant increase of survival. After 20 h, markedly depressed serum levels of interferon (IFN)-gamma and interleukin (IL)-6 but not IL-10 and tumour necrosis factor (TNF)-alpha were observed in p65 antisense-treated compared to mismatched-treated animals. These data show that the ability of S. typhimurium to induce lethal septic shock is critically dependent on their capacity to induce NF-kappaB.


Asunto(s)
FN-kappa B/genética , Oligodesoxirribonucleótidos Antisentido , Infecciones por Salmonella/prevención & control , Salmonella typhimurium/inmunología , Choque Séptico/prevención & control , Tionucleótidos , Animales , Disparidad de Par Base , Citocinas/sangre , Citocinas/inmunología , Femenino , Fluoresceína-5-Isotiocianato , Colorantes Fluorescentes , Variación Genética , Hígado/patología , Ratones , Ratones Endogámicos BALB C , FN-kappa B/inmunología , Iniciación de la Cadena Peptídica Traduccional , Infecciones por Salmonella/sangre , Infecciones por Salmonella/inmunología , Infecciones por Salmonella/microbiología , Salmonella typhimurium/crecimiento & desarrollo , Choque Séptico/sangre , Choque Séptico/inmunología , Choque Séptico/microbiología , Factor de Transcripción ReIA
17.
Genomics ; 77(1-2): 50-7, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11543632

RESUMEN

The combination of high and low density cDNA filter array technology potentially permits both the identification of subsets of induced genes and convenient and rapid multisample expression profiling of such subsets under a variety of conditions. The JAK/STAT1 pathway for IFN-gamma signaling in human cells has been well characterized, but the extent and importance of additional pathways remain to be established. Here, using high-density filter arrays of the RZPD UniGene set, we identified 18 novel IFN-gamma-inducible genes. Expression profiling was carried out using low-density arrays representing both novel and known IFN-gamma-inducible genes. Initial experiments failed to detect evidence for any novel non-JAK-dependent pathways in cells expressing a kinase-dead JAK2. The data, however, validated the potential of the combined methods in establishing rapid and convenient expression profiling of several hundred genes in response to any ligand of choice.


Asunto(s)
Perfilación de la Expresión Génica , Interferón gamma/farmacología , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Proteínas Proto-Oncogénicas , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Janus Quinasa 2 , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/fisiología , Transducción de Señal , Células Tumorales Cultivadas
18.
Eur J Clin Invest ; 31(2): 171-8, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11168457

RESUMEN

HIV infection is characterized by an enhanced oxidant burden and a systemic deficiency of the tripeptide glutathione (GSH), a major antioxidant. The semi-essential amino acid cysteine is the main source of the free sulfhydryl group of GSH and limits its synthesis. Therefore, different strategies to supplement cysteine supply have been suggested to increase glutathione levels in HIV-infected individuals. The aim of this study was to evaluate the effect of oral supplementation with two different cysteine-rich whey protein formulas on plasma GSH levels and parameters of oxidative stress and immune status in HIV-infected patients. In a prospective double blind clinical trial, 30 patients (25 male, 5 female; mean age (+/- SD) 42 +/- 9.8 years) with stable HIV infection (221 +/- 102 CD4 + lymphocytes L-1) were randomized to a supplemental diet with a daily dose of 45 g whey proteins of either Protectamin (Fresenius Kabi, Bad Hamburg, Germany) or Immunocal (Immunotec, Vandreuil, Canada) for two weeks. Plasma concentrations of total, reduced and oxidized GSH, superoxide anion (O2-) release by blood mononuclear cells, plasma levels of TNF-alpha and interleukins 2 and 12 were quantified with standard methods at baseline and after therapy. Pre-therapy, plasma GSH levels (Protectamin: 1.92 +/- 0.6 microM; Immunocal: 1.98 +/- 0.9 microM) were less than normal (2.64 +/- 0.7 microM, P = 0.03). Following two weeks of oral supplementation with whey proteins, plasma GSH levels increased in the Protectamin group by 44 +/- 56% (2.79 +/- 1.2 microM, P = 0.004) while the difference in the Immunocal group did not reach significance (+ 24.5 +/- 59%, 2.51 +/- 1.48 microM, P = 0.43). Spontaneous O2- release by blood mononuclear cells was stable (20.1 +/- 14.2 vs. 22.6 +/- 16.1 nmol h-1 10-6 cells, P = 0.52) whereas PMA-induced O2- release decreased in the Protectamin group (53.7 +/- 19 vs. 39.8 +/- 18 nmol h-1 10-6 cells, P = 0.04). Plasma concentrations of TNF-alpha and interleukins 2 and 12 (P > 0.08, all comparisons) as well as routine clinical parameters remained unchanged. Therapy was well tolerated. In glutathione-deficient patients with advanced HIV-infection, short-term oral supplementation with whey proteins increases plasma glutathione levels. A long-term clinical trial is clearly warranted to see if this "biochemical efficacy" of whey proteins translates into a more favourable course of the disease.


Asunto(s)
Glutatión/sangre , Infecciones por VIH/tratamiento farmacológico , Proteínas de la Leche/uso terapéutico , Administración Oral , Adulto , Antioxidantes/análisis , Suplementos Dietéticos , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monocitos/efectos de los fármacos , Superóxidos/metabolismo , Proteína de Suero de Leche
19.
Int J STD AIDS ; 11(9): 609-10, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10997507

RESUMEN

Epidemiological features suggest a link between Hodgkin's disease (HD) and Epstein-Barr virus (EBV) infection. Indeed, EBV genome and expression of latent antigens can be found in Reed-Sternberg cells. In the majority of cases HD in HIV patients seems to be EBV-associated. We report on a 51-year-old HIV-infected patient in whom EBV-positive HD of mixed cellularity rapidly developed within one month after cessation of treatment with intravenous foscarnet.


Asunto(s)
Antivirales/uso terapéutico , Infecciones por Virus de Epstein-Barr/etiología , Foscarnet/uso terapéutico , Infecciones por VIH/complicaciones , Enfermedad de Hodgkin/etiología , Antivirales/administración & dosificación , Infecciones por Virus de Epstein-Barr/prevención & control , Foscarnet/administración & dosificación , Infecciones por VIH/tratamiento farmacológico , Enfermedad de Hodgkin/prevención & control , Enfermedad de Hodgkin/virología , Humanos , Masculino , Persona de Mediana Edad
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