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Acute respiratory tract infections (ARI) are common diseases in children and adults and could cause severe infections in high-risk patients, like the immunocompromised and elderly, and are the leading cause of morbidity, hospitalization and mortality. This study aimed to explore the prevalence of respiratory viruses and the clinical impact of single- and multi-infection among hospitalized patients in various age groups. 3578 nasopharyngeal swabs (NPS) were analyzed for pathogen detection of acute respiratory tract infections. 930 out of 3578 NPS were diagnosed positive for at least one respiratory virus. The distribution of viral infections, prevalence and pathogen, differed significantly among age groups. Most RTI are observed in the age group over 65 years (50.6%) with a high SARS-CoV2 prevalence, following by group <5 years (25.6%), where the most frequently detected viruses were RSV, Rhinovirus, FluA-H3, MPV, and AdV. The co-infection rate also varies according to age and, in some cases, especially in older adults, could have severe clinical impact. This study emphasizes that it is important to know and analyze, in all age groups of hospitalized patients, the epidemiology of respiratory viruses, the prevalence of coinfections, and the clinical impact of various pathogens. Furthermore, in a clinical setting, the rapid diagnosis of respiratory infections by means of molecular tests is crucial not only to avoid hospital outbreaks, but also to allow early and optimal treatment to reduce morbidity and mortality.
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Coinfección , Infecciones del Sistema Respiratorio , Humanos , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/virología , Anciano , Adulto , Persona de Mediana Edad , Preescolar , Adolescente , Niño , Masculino , Adulto Joven , Femenino , Lactante , Coinfección/epidemiología , Coinfección/virología , Anciano de 80 o más Años , COVID-19/epidemiología , Prevalencia , Hospitalización , SARS-CoV-2 , Virosis/epidemiología , Virosis/virología , Recién Nacido , Pandemias , Virus/aislamiento & purificación , Virus/clasificación , Virus/genéticaRESUMEN
A unique case of severe measles complicated by multiple features of gas accumulation is described, on the ground of the available literature evidences. Complications from measles have been reported in every organ system and they may vary by age and underlying conditions. Pneumomediastinum is usually associated with subcutaneous emphysema and pneumopericardium, but rarely associated with pneumothorax. We report extremely rare simultaneous occurrence of self-limiting pneumomediastinum, pneumopericardium, subcutaneous neck and chest region emphysema, and pneumothorax, in a 19-year-old girl with measles. A review of the literature has documented only one previous report of spontaneous pneumomediastinum, subcutaneous emphysema and pneumothorax in the course of measles, and no previous cases reported the association of pneumomediastinum, subcutaneous emphysema, pneumopericardium and pneumothorax complicating measles.
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Enfisema Mediastínico , Neumopericardio , Neumotórax , Enfisema Subcutáneo , Femenino , Humanos , Adulto Joven , Adulto , Neumotórax/etiología , Neumotórax/complicaciones , Enfisema Mediastínico/etiología , Enfisema Mediastínico/complicaciones , Neumopericardio/etiología , Neumopericardio/complicaciones , Tomografía Computarizada por Rayos X , Enfisema Subcutáneo/etiología , Enfisema Subcutáneo/complicacionesRESUMEN
An intriguing case of lethal rickettsiosis caused by Rickettsia conorii complicated by brain involvement and the presence anti-phospholipid antibodies is presented and discussed, on the ground of recent literature evidences.
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Fiebre Botonosa , Rickettsia conorii , Humanos , Fiebre Botonosa/microbiologíaRESUMEN
A unique report of Schönlein-Henoch purpura (SHP) associated with a recent Giardia lamblia enteric infection is described and discussed on the ground of the available literature. Tinidazole plus an appropriate probiotic therapy, including Lactobacillus reuteri and vitamin D, proved to be effective in the condition. SHP is an immunocomplex-mediated disorder characterised by a number of differently associated signs and symptoms, leading to the possible involvement of the skin, joints, abdomen and kidneys. Recent bacterial, viral, or protozoan infections may trigger the disease onset in patients of all ages. The paper describes the first case of SHP triggered by a giardiasis. Tinidazole plus an appropriate probiotic therapy, i.e. L. reuteri and vitamin D proved to be effective in this condition. To our knowledge, this is the first reported case of lambliasis-associated SHP described in an international traveller.
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Giardiasis , Vasculitis por IgA , Humanos , Vasculitis por IgA/complicaciones , Vasculitis por IgA/diagnóstico , Giardiasis/complicaciones , Tinidazol , Vitamina D , ItaliaRESUMEN
Two recent cases of extremely severe thrombocytopenic purpura related to a concomitant cytomegalovirus infection, either associated or not with an underlying immunosuppression, draw our attention on this intriguing pathologic association, on the ground of an updated literature review.
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Infecciones por Citomegalovirus , Trombocitopenia , Humanos , Infecciones por Citomegalovirus/complicaciones , Huésped Inmunocomprometido , Trombocitopenia/etiologíaRESUMEN
Both the safety and effectiveness of intrathecal tigecycline (TGC) for treatment of infections of the central nervous system (CNS) are discussed using the clinical findings from a study of a recent patient who came to our attention, along with a literature review. Although penetration into the CNS is low (approximately 11%), intraventricular TGC could help treat patients with severe post- neurosurgical CNS infections. The use of multiple routes of TGC administration appears to be encouraging and should be considered in managing life-threatening intraventricular infections.
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Objectives: The dysregulated immune response occurring upon COVID-19 infection can lead to tissue damage and organ failure. Different therapeutic strategies are needed to cope with the current and future outspread of COVID-19, including antiviral and anti-inflammatory agents. We describe the outcome of hospitalized patients treated with canakinumab and remdesivir plus the standard of care therapy. Methods: This observational study describes the outcome of the combination of canakinumab (450 mg for patients ≥40 and <60 kg, 600 mg for those ≥60 and <80 kg, or 750 mg for patients ≥80 kg) and 200 mg remdesivir intravenous infusion, plus standard of care (SOC), in 17 moderate-to-severe COVID-19 patients hospitalized in the "Annunziata" Hospital, Cosenza, Italy, between August and November 2021. Hematological markers, biochemical, and hemogasanalysis values at baseline versus day 7 of combination treatment were compared by paired t test after checking for normal distribution and correcting for multiple comparison. Results: The median age of patients was 64 years (range: 39-85), and the median hospitalization time (calculated on the 16 patients that were not transferred to intensive care unit) was of 12.5 days (range: 7-35 days); 15/17 patients (88%) did not experience complications. After 7 days of combination therapy, all the inflammatory parameters were significantly reduced with the exception of procalcitonin; moreover, hematological prognostic markers such neutrophil-to-lymphocyte ratio, CRP-to-lymphocyte ratio, and derived neutrophil-to-lymphocyte ratio reduced. Overall, 16/17 patients (94%) recovered after 14 days. Conclusions: Canakinumab and remdesivir treatment, in addition to SOC, in the early stage of moderate-to-severe COVID-19 showed promising outcomes in terms of safety and effectiveness potentially leading to a reduction in inflammatory and hematological prognostic markers after 7 days of treatment.
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COVID-19 , Humanos , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , SARS-CoV-2 , Estudios Retrospectivos , Resultado del Tratamiento , Tratamiento Farmacológico de COVID-19 , Antivirales/efectos adversosRESUMEN
Thrombotic thrombocytopenic purpura (TTP) is a potentially life-threatening, rare acute thrombotic microangiopathy (TMA), caused by a severe ADAMTS13 deficiency. As the COVID-19 pandemic rapidly spread around the globe, much data about the pathogenicity of this virus were published. Soon after the detection of the first cases of COVID-19, it was clear that there was a wide range of COVID coagulopathy manifestations, such as deep venous thrombosis, pulmonary thromboembolism, and thrombotic microangiopathies. In the literature, little data have been reported about the association between TTP and COVID-19, and the treatment of COVID-19-associated TTP is still under debate. Here we present the case of a 46-year-old woman who developed a COVID-associated TTP, successfully treated with plasma exchange (PEX), steroids, and caplacizumab.
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The majority of "serrated pathway" colorectal cancers have mutation of the BRAF oncogene and display the CpG island methylator phenotype (CIMP). Half these cancers have microsatellite instability (MSI) and an excellent prognosis. In the absence of MSI (microsatellite stable, MSS), BRAF mutation has been associated with a particularly poor prognosis. "Traditional pathway" cancers are BRAF wild type. Mutation of p53 is common and this correlates with advanced stage. We therefore hypothesized that p53 mutation would be common in MSS/BRAF mutant colorectal cancer. One thousand and eighty-one colorectal cancers were screened for BRAF mutation to identify two BRAF mutant study groups (MSI: n = 77; MSS: n = 69) and a BRAF wild type control group (n = 101). These were screened for p53 mutation by high resolution melt analysis and classified for CIMP and MGMT methylation by quantitative methylation specific PCR. Molecular data were compared to patient age, gender, tumor location and stage. p53 was mutated significantly more frequently in MSS/BRAF mutant (28/69, 40.6%) compared to MSI/BRAF mutant cancers (13/77, 16.9%), but this mutation rate did not differ from MSS/BRAF wild type cancers (47/101, 46.5%)(p < 0.0001). CIMP was less common in MSS/BRAF mutant (26/47, 55.3%) compared to MSI/BRAF mutant cancers (41/54, 75.9%), but was more common than in MSS/BRAF wild type cancers (3/85, 3.5%) (p < 0.0001). MSS/BRAF mutant cancers were more commonly proximal (38/54, 70.3%), but were similar to MSS/BRAF wild type cancers in terms of patient age, gender distribution and stage at presentation. MSS/BRAF mutant cancers share molecular and clinical features of both the serrated and traditional pathways of colorectal tumorigenesis.
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Neoplasias Colorrectales/genética , Genes p53 , Repeticiones de Microsatélite , Mutación , Proteínas Proto-Oncogénicas B-raf/genética , Anciano , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Islas de CpG , Metilación de ADN , Metilasas de Modificación del ADN/genética , Metilasas de Modificación del ADN/metabolismo , Enzimas Reparadoras del ADN/genética , Enzimas Reparadoras del ADN/metabolismo , Femenino , Humanos , Masculino , Inestabilidad de Microsatélites , Fenotipo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas B-raf/metabolismo , Proteínas Proto-Oncogénicas p21(ras) , Transducción de Señal , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo , Proteínas ras/genética , Proteínas ras/metabolismoRESUMEN
Oncogenic PIK3CA mutations contribute to colorectal tumorigenesis by activating AKT signaling to decrease apoptosis and increase tumor invasion. A synergistic association of PIK3CA mutation with KRAS mutation has been suggested to increase AKT signaling and resistance to antiepidermal growth factor receptor inhibitor therapy for advanced colorectal cancer, although studies have been conflicting. We sought to clarify this by examining PIK3CA mutation frequency in relation to other key molecular features of defined pathways of tumorigenesis. PIK3CA mutation was assessed by high resolution melt analysis in 829 colorectal cancer samples and 426 colorectal polyps. Mutations were independently correlated with clinicopathological features including patient age, sex and tumor location as well as molecular features including microsatellite instability, KRAS and BRAF mutation, MGMT methylation and the CpG Island Methylator Phenotype (CIMP). Mutation of the helical (Exon 9) and catalytic (Exon 20) domain mutation hotspots were also examined independently. Overall, PIK3CA mutation was positively correlated with KRAS mutation (p < 0.001), MGMT methylation (p = 0.007) and CIMP (p < 0.001). Novel, exon-specific associations linked Exon 9 mutations to a subgroup of cancers characterized by KRAS mutation, MGMT methylation and CIMP-Low, whilst Exon 20 mutations were more closely linked to features of serrated pathway tumors including BRAF mutation, microsatellite instability and CIMP-High or Low. PIK3CA mutations were uncommonly, but exclusively, seen in tubulovillous adenomas (4/124, 3.2%) and 1/4 (25.0%) tubulovillous adenomas with a focus of cancer. These data provide insight into the molecular events driving traditional versus serrated pathway tumorigenesis.
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Pólipos del Colon/genética , Neoplasias Colorrectales/genética , Oncogenes , Fosfatidilinositol 3-Quinasas/genética , Anciano , Secuencia de Bases , Fosfatidilinositol 3-Quinasa Clase I , Estudios de Cohortes , Cartilla de ADN , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
This brief report documents the safety and efficacy of high-dose tigecycline as a salvage-therapy in in a case series of five patients with serious central nervous system (CNS) rocky mountain spotted fever (RMSF). These severily ill patients were unable to take any oral drug therapy, parenteral doxycycline was unavailable and absorption of oral doxycycline was a concern in these critically ill patients. As far as we know, we report the successfull use of tigecycline for the treatment of rickettsial meningitis for the first time in Italy. We suggest more studies on tigecycline in severe CNS infections from Rickettsia species and multi-drug resistant bacteria, especially the use of tigecycline at higher than standard doses in these life-threathening infectious diseases.
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Glecaprevir (GLE)/pibrentasvir (PIB) is a pangenotypic direct-acting antiviral regimen approved for treating chronic hepatitis C virus. Primary treatment and re-treatment with GLE/PIB are effective and safe for patients without decompensated liver cirrhosis and chronic hepatitis C in a real-world clinical setting. However, in the context of compensated cirrhosis and concomitant administration of inhibitors of cytochromes, a careful monitoring of liver biomarkers, as well as therapeutic drug monitoring (TDM), may be advisable during GLE/PIB therapy. The GLE / PIB combination is very effective and safe in achieving a sustained virological response, but it can be associated with the development of severe hepatic adverse events, which require virological and serum concentration monitoring of the two drugs to prevent a serious liver damage. The possible onset of hyperbilirubinemia must not necessarily lead to the suspension of therapy, because the phenomenon may be transient. We report what is likely the first known case of severe jaundice after treatment with GLE/PIB in Italy in a patient with compensated chronic hepatitis in the context of HIV disease.
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Infecciones por VIH , Hepatitis C Crónica , Ictericia , Humanos , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Antivirales/efectos adversos , Hiperbilirrubinemia/inducido químicamente , Hiperbilirrubinemia/tratamiento farmacológico , Ictericia/inducido químicamente , Ictericia/tratamiento farmacológico , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológicoRESUMEN
BACKGROUND: DNA methylation varies throughout the normal colorectal mucosa and DNA methylation in normal appearing mucosa is associated with serrated and adenomatous neoplasia elsewhere within the colorectum. AIMS: The purpose of this study was to measure luminal chemistry, rectal proliferation and mucosal DNA methylation and thus determine whether regional and pathological patterns of DNA methylation could be explained by luminal and epithelial factors. METHODS: Twenty healthy subjects had normal rectal mucosal biopsies and a 24-h fecal collection. Rectal biopsies were analyzed for epithelial proliferation (Ki67 immunohistochemistry) and DNA methylation at 17 different markers, including "type A" markers (ESR1, GATA5, HIC1, HPP1, SFRP1), "type C" markers (MGMT, MLH1, CDKN2A, MINT1, MINT2, MINT31, IGF2, CACNA1G, NEUROG1, SOCS1, RUNX3), and LINE-1. Fecal analysis included short-chain fatty acids (SCFA), pH and ammonia. Mean "type A" and CIMP panel methylation Z-scores were calculated. RESULTS: Rectal proliferation was significantly correlated with methylation at ESR1 (ρ = 0.81, P = 0.003) and GATA5 (ρ = 0.78, P = 0.012). LINE-1 methylation was 71.7 vs. 74.1%, in patients with "low" and "high" fecal total SCFA concentration (defined by the median value), respectively (P = 0.0019). On multivariate linear regression "type A" methylation was independently associated with rectal proliferation (P = 0.001). LINE-1 methylation was directly associated with rectal proliferation (P = 0.038) and total fecal SCFA concentration (P = 0.002), and inversely associated with fecal NH(3) concentrations (P = 0.003). CONCLUSIONS: DNA methylation in normal rectal mucosa is associated with crypt proliferation and fecal SCFA concentration. These associations may help to explain regional differences in DNA methylation as well as providing a possible link between the colorectal lumen and carcinogenesis.
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Metilación de ADN/fisiología , Ácidos Grasos Volátiles/análisis , Heces/química , Mucosa Intestinal/metabolismo , Recto/metabolismo , Focos de Criptas Aberrantes/metabolismo , Focos de Criptas Aberrantes/patología , Adulto , Anciano , Amoníaco/análisis , Biomarcadores , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Femenino , Humanos , Mucosa Intestinal/patología , Masculino , Persona de Mediana Edad , Recto/patologíaRESUMEN
Ivabradine is a pure heart rate-lowering drug that acts directly on the sinus node and does not affect atrioventricular or intraventricular conduction times, myocardial contractility or ventricular repolarization. Ivabradine is used in the treatment of adults with New York Heart Association (NYHA) class II-IV chronic heart failure (CHF) with systolic dysfunction, in sinus rhythm, with a heart rate of ≥75 beats per minute (bpm). This report describes the beneficial effect of ivabradine on clinical parameters in a HIV-infected patient with dilated cardiomyopathy presenting with NYHA class III CHF symptoms. Ivabradine improved functional capacity and left ventricular (LV) systolic function in our patient with HIV-related dilated cardiomyopathy and CHF. This report also lists the summaries of potential clinically significant interaction, likely to require additional monitoring, alteration of drug dosage or timing of administration, between ivabradine and antiretroviral drugs.
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Cardiomiopatía Dilatada , Infecciones por VIH , Insuficiencia Cardíaca , Adulto , Benzazepinas/farmacología , Benzazepinas/uso terapéutico , Cardiomiopatía Dilatada/diagnóstico , Cardiomiopatía Dilatada/tratamiento farmacológico , Cardiomiopatía Dilatada/etiología , Enfermedad Crónica , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Insuficiencia Cardíaca/tratamiento farmacológico , Frecuencia Cardíaca , Humanos , Ivabradina/farmacología , Ivabradina/uso terapéutico , Volumen Sistólico , Resultado del TratamientoRESUMEN
INTRODUCTION: The fully-human monoclonal anti-interleukin (IL)-1ß antibody canakinumab may inhibit the production of inflammatory mediators in patients with coronavirus disease 2019 (COVID-19) and the hyperinflammatory response potentially leading to acute respiratory distress syndrome. OBJECTIVES: The goal of our retrospective, observational analysis was to evaluate the safety and efficacy of subcutaneous (s.c.) canakinumab in combination with our standard of care (SOC) treatment of selected patients with COVID-19 with respiratory failure and elevated reactive pro-inflammatory markers. METHODS: Eight participants received two doses of s.c. canakinumab 150 mg (or 2 mg/kg for participants weighing ≤40 kg) in addition to SOC. 12 patients received only SOC treatment. RESULTS: Canakinumab treatment reduced the need for mechanical ventilation and reduced proinflammatory markers, resulting in an amelioration of the final outcome, with respect to the control group who received SOC alone. The treatment was safe and well tolerated; no adverse events were reported. CONCLUSION: The use of canakinumab (300 mg, s.c.) in the early stage of COVID-19 with mild-to-moderate respiratory failure was superior to SOC at preventing clinical deterioration and may warrant further investigation as a treatment option for patients with COVID-19 who experience a hyperinflammatory response in the early stage of the disease.
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Anticuerpos Monoclonales Humanizados , COVID-19 , Interleucina-1beta , Respiración Artificial , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/inmunología , Biomarcadores/sangre , COVID-19/complicaciones , COVID-19/epidemiología , COVID-19/inmunología , COVID-19/terapia , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Mediadores de Inflamación/sangre , Interleucina-1beta/antagonistas & inhibidores , Interleucina-1beta/inmunología , Italia/epidemiología , Masculino , Persona de Mediana Edad , Monitorización Inmunológica/métodos , Evaluación de Procesos y Resultados en Atención de Salud , Selección de Paciente , Respiración Artificial/métodos , Respiración Artificial/estadística & datos numéricos , Estudios Retrospectivos , SARS-CoV-2 , Tiempo de TratamientoRESUMEN
Oseltamivir is an orally administered antiviral medication that selectively inhibits the influenza neuraminidase enzymes that are essential for viral replication and it is active against both influenza A and B viruses. Oseltamivir is indicated for therapy or post-exposure prevention of influenza A and B. Side effects are uncommon and include mild nausea, gastrointestinal upset, dizziness, and headache. Despite widespread use, oseltamivir has not been associated with clinically apparent liver injury; however, there is growing evidence of possible toxic liver involvement during oseltamivir therapy. To the best of our knowledge, this is the first reported case in Italy linking the development of acute hepatitis and oseltamivir therapy, in a patient suffering from influenza H1N1 infection. We also present a review of the literature on cases of oseltamivir hepatotoxicity, through the consultation of PubMed database, the bibliographical references of various articles and an extensive search using Google. In view of the analyzed results, we suggest that experts should carefully consider the need for inclusion of potential serious liver reactions be added to the oseltamivir product label.
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Hepatitis , Subtipo H1N1 del Virus de la Influenza A , Gripe Humana , Enfermedad Aguda , Antivirales/efectos adversos , Hepatitis/tratamiento farmacológico , Humanos , Gripe Humana/tratamiento farmacológico , Oseltamivir/efectos adversosRESUMEN
UNLABELLED: Cholestatic liver diseases, such as cystic fibrosis (CF) liver disease and biliary atresia, predominate as causes of childhood cirrhosis. Despite diverse etiologies, the stereotypic final pathway involves fibrogenesis where hepatic stellate cells (HSCs) are recruited, producing excess collagen which initiates biliary fibrosis. A possible molecular determinant of this recruitment, monocyte chemotaxis protein-1 (MCP-1), an HSC-responsive chemokine, was investigated in CF liver disease and biliary atresia. The bile-duct-ligated rat and in vitro coculture models of cholestatic liver injury were used to further explore the role of MCP-1 in HSC recruitment and proposed mechanism of induction via bile acids. In both CF liver disease and biliary atresia, elevated hepatic MCP-1 expression predominated in scar margin hepatocytes, closely associated with activated HSCs, and was also expressed in cholangiocytes. Serum MCP-1 was elevated during early fibrogenesis. Similar observations were made in bile-duct-ligated rat liver and serum. Hepatocytes isolated from cholestatic rats secreted increased MCP-1 which avidly recruited HSCs in coculture. This HSC chemotaxis was markedly inhibited in interventional studies using anti-MCP-1 neutralizing antibody. In CF liver disease, biliary MCP-1 was increased, positively correlating with levels of the hydrophobic bile acid, taurocholate. In cholestatic rats, increased MCP-1 positively correlated with taurocholate in serum and liver, and negatively correlated in bile. In normal human and rat hepatocytes, taurocholate induced MCP-1 expression. CONCLUSION: These observations support the hypothesis that up-regulation of hepatocyte-derived MCP-1, induced by bile acids, results in HSC recruitment in diverse causes of cholestatic liver injury, and is a key early event in liver fibrogenesis in these conditions. Therapies aimed at neutralizing MCP-1 or bile acids may help reduce fibro-obliterative liver injury in childhood cholestatic diseases.
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Quimiocina CCL2/fisiología , Colestasis Intrahepática/fisiopatología , Fibrosis Quística/patología , Hepatocitos/patología , Hígado/patología , Ácido Taurocólico/fisiología , Animales , Biopsia , Movimiento Celular , Quimiocina CCL2/genética , Niño , Preescolar , Colestasis Intrahepática/patología , Cartilla de ADN , Células Estrelladas Hepáticas/patología , Células Estrelladas Hepáticas/fisiología , Humanos , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
BACKGROUND: Thrombospondin-4 (THBS4) is a member of the extracellular calcium-binding protein family and is involved in cell adhesion and migration. The aim of this study was to evaluate the potential role of deregulation of THBS4 expression in colorectal carcinogenesis. Of particular interest was the possible silencing of expression by methylation of the CpG island in the gene promoter. METHODS: Fifty-five sporadic colorectal tumours stratified for the CpG Island Methylator Phenotype (CIMP) were studied. Immunohistochemical staining of THBS4 protein was assessed in normal and tumour specimens. Relative levels of THBS4 transcript expression in matched tumours and normal mucosa were also determined by quantitative RT-PCR. Colony forming ability was examined in 8 cell lines made to overexpress THBS4. Aberrant promoter hypermethylation was investigated as a possible mechanism of gene disruption using MethyLight. Methylation was also assessed in the normal colonic tissue of 99 patients, with samples biopsied from four regions along the length of the colon. RESULTS: THBS4 expression was significantly lower in tumour tissue than in matched normal tissue. Immunohistochemical examination demonstrated that THBS4 protein was generally absent from normal epithelial cells and tumours, but was occasionally expressed at low levels in the cytoplasm towards the luminal surface in vesicular structures. Forced THBS4 over-expression caused a 50-60% repression of tumour colony growth in all eight cell lines examined compared to control cell lines. Tumours exhibited significantly higher levels of methylation than matched normal mucosa, and THBS4 methylation correlated with the CpG island methylator phenotype. There was a trend towards decreased gene expression in tumours exhibiting high THBS4 methylation, but the correlation was not significant. THBS4 methylation was detectable in normal mucosal biopsies where it correlated with increasing patient age and negatively with the occurrence of adenomas elsewhere in the colon. CONCLUSIONS: THBS4 shows increased methylation in colorectal cancer, but this is not strongly associated with altered gene expression, either because methylation has not always reached a critical level or because other factors influence THBS4 expression. THBS4 may act as a tumour suppressor gene, demonstrated by its suppression of tumour colony formation in vitro. THBS4 methylation is detectable in normal colonic mucosa and its level may be a biomarker for the occurrence of adenomas and carcinoma.