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BACKGROUND: Asthma is a heterogeneous disease and development of novel therapeutics requires an understanding of pathophysiologic phenotypes. The purpose of the ADEPT study was to correlate clinical features and biomarkers with molecular characteristics, by profiling asthma (NCT01274507). This report presents for the first time the study design, and characteristics of the recruited subjects. METHODS: Patients with a range of asthma severity and healthy non-atopic controls were enrolled. The asthmatic subjects were followed for 12 months. Assessments included history, patient questionnaires, spirometry, airway hyper-responsiveness to methacholine, fractional exhaled nitric oxide (FENO), and biomarkers measured in induced sputum, blood, and bronchoscopy samples. All subjects underwent sputum induction and 30 subjects/cohort had bronchoscopy. RESULTS: Mild (n = 52), moderate (n = 55), severe (n = 51) asthma cohorts and 30 healthy controls were enrolled from North America and Western Europe. Airflow obstruction, bronchodilator response and airways hyperresponsiveness increased with asthma severity, and severe asthma subjects had reduced forced vital capacity. Asthma control questionnaire-7 (ACQ7) scores worsened with asthma severity. In the asthmatics, mean values for all clinical and biomarker characteristics were stable over 12 months although individual variability was evident. FENO and blood eosinophils did not differ by asthma severity. Induced sputum eosinophils but not neutrophils were lower in mild compared to the moderate and severe asthma cohorts. CONCLUSIONS: The ADEPT study successfully enrolled asthmatics across a spectrum of severity and non-atopic controls. Clinical characteristics were related to asthma severity and in general asthma characteristics e.g. lung function, were stable over 12 months. Use of the ADEPT data should prove useful in defining biological phenotypes to facilitate personalized therapeutic approaches.
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Antiasmáticos/uso terapéutico , Asma/diagnóstico , Asma/tratamiento farmacológico , Broncodilatadores/uso terapéutico , Pulmón/efectos de los fármacos , Medicina de Precisión , Adolescente , Adulto , Anciano , Asma/epidemiología , Asma/metabolismo , Asma/fisiopatología , Biomarcadores/metabolismo , Broncoconstricción/efectos de los fármacos , Canadá/epidemiología , Estudios de Casos y Controles , Europa (Continente)/epidemiología , Femenino , Humanos , Estudios Longitudinales , Pulmón/metabolismo , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Selección de Paciente , Fenotipo , Valor Predictivo de las Pruebas , Prevalencia , Proyectos de Investigación , Pruebas de Función Respiratoria , Factores de Riesgo , Índice de Severidad de la Enfermedad , Esputo/metabolismo , Encuestas y Cuestionarios , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos/epidemiología , Adulto JovenRESUMEN
Further understanding of the molecular biology and pathogenesis of hepatocellular carcinoma (HCC) is crucial for future therapeutic development. SMAD4, recognized as an important tumor suppressor, is a central mediator of transforming growth factor beta (TGFB) and bone morphogenetic protein (BMP) signaling. This study investigated the role of SMAD4 in HCC. Nuclear localization of SMAD4 was observed in a cohort of 140 HCC patients using tissue microarray. HCC cell lines were used for functional assay in vitro and in immune-deficient mice. Nuclear SMAD4 levels were significantly increased in patient HCC tumors as compared with adjacent tissues. Knockdown of SMAD4 significantly reduced the efficiency of colony formation and migratory capacity of HCC cells in vitro and was incompatible with HCC tumor initiation and growth in mice. Knockdown of SMAD4 partially conferred resistance to the anti-growth effects of BMP ligand in HCC cells. Importantly, simultaneous elevation of SMAD4 and phosphorylated SMAD2/3 is significantly associated with poor patient outcome after surgery. Although high levels of SMAD4 can also mediate an antitumor function by coupling with phosphorylated SMAD1/5/8, this signaling, however, is absent in majority of our HCC patients. In conclusion, this study revealed a highly non-canonical tumor-promoting function of SMAD4 in HCC. The drastic elevation of nuclear SMAD4 in sub-population of HCC tumors highlights its potential as an outcome predictor for patient stratification and a target for personalized therapeutic development.
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Carcinogénesis , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Proteína Smad4/fisiología , Animales , Línea Celular Tumoral , Técnicas de Silenciamiento del Gen , Silenciador del Gen , Humanos , Ratones , Fosforilación , Proteína Smad2/metabolismo , Proteína smad3/metabolismo , Proteína Smad4/genéticaRESUMEN
The incidence of Barrett's esophagus (BE)-associated esophageal adenocarcinoma (EAC) is increasing. Next-generation sequencing (NGS) provides an unprecedented opportunity to uncover genomic alterations during BE pathogenesis and progression to EAC, but treatment-naive surgical specimens are scarce. The objective of this study was to establish the feasibility of using widely available endoscopic mucosal biopsies for successful NGS, using samples obtained from a BE 'progressor'. Paired-end whole-genome NGS was performed on the Illumina platform using libraries generated from mucosal biopsies of normal squamous epithelium (NSE), BE and EAC obtained from a patient who progressed to adenocarcinoma during endoscopic surveillance. Selective validation studies, including Sanger sequencing, immunohistochemistry and functional assays, were performed to confirm the NGS findings. NGS identified somatic nonsense mutations of AT-rich interactive domain 1A (SWI like) (ARID1A) and PPIE and an additional 37 missense mutations in BE and/or EAC, which were confirmed by Sanger sequencing. ARID1A mutations were detected in 15% (3/20) high-grade dysplasia (HGD)/EAC patients. Immunohistochemistry performed on an independent archival cohort demonstrated ARID1A protein loss in 0% (0/76), 4.9% (2/40), 14.3% (4/28), 16.0% (8/50) and 12.2% (12/98) of NSE, BE, low-grade dysplasia, HGD and EAC tissues, respectively, and was inversely associated with nuclear p53 accumulation (P=0.028). Enhanced cell growth, proliferation and invasion were observed on ARID1A knockdown in EAC cells. In addition, genes downstream of ARID1A that potentially contribute to the ARID1A knockdown phenotype were identified. Our studies establish the feasibility of using mucosal biopsies for NGS, which should enable the comparative analysis of larger 'progressor' versus 'non-progressor' cohorts. Further, we identify ARID1A as a novel tumor-suppressor gene in BE pathogenesis, reiterating the importance of aberrant chromatin in the metaplasia-dysplasia sequence.
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Esófago de Barrett/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Proteínas Nucleares/genética , Factores de Transcripción/genética , Proteínas Supresoras de Tumor/genética , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Anciano , Esófago de Barrett/metabolismo , Esófago de Barrett/patología , Biopsia , Western Blotting , Línea Celular Tumoral , Proliferación Celular , Proteínas de Unión al ADN , Endoscopios , Epitelio/metabolismo , Epitelio/patología , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Femenino , Redes Reguladoras de Genes , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Mutación Missense , Proteínas Nucleares/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimorfismo de Nucleótido Simple , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Transcripción/metabolismo , Transcriptoma , Proteínas Supresoras de Tumor/metabolismoRESUMEN
Congenital disorders of glycosylation (CDG) are a growing group of inherited metabolic disorders where enzymatic defects in the formation or processing of glycolipids and/or glycoproteins lead to variety of different diseases. The deficiency of GDP-Man:GlcNAc2-PP-dolichol mannosyltransferase, encoded by the human ortholog of ALG1 from yeast, is known as ALG1-CDG (CDG-Ik). The phenotypical, molecular and biochemical analysis of a severely affected ALG1-CDG patient is the focus of this paper. The patient's main symptoms were feeding problems and diarrhea, profound hypoproteinemia with massive ascites, muscular hypertonia, seizures refractory to treatment, recurrent episodes of apnoea, cardiac and hepatic involvement and coagulation anomalies. Compound heterozygosity for the mutations c.1145T>C (M382T) and c.1312C>T (R438W) was detected in the patient's ALG1-coding sequence. In contrast to a previously reported speculation on R438W we confirmed both mutations as disease-causing in ALG1-CDG.
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Trastornos Congénitos de Glicosilación/genética , Manosiltransferasas/genética , Mutación , Secuencia de Aminoácidos , Resultado Fatal , Glicosilación , Humanos , Lactante , Masculino , Datos de Secuencia Molecular , Alineación de SecuenciaRESUMEN
BACKGROUND: In untreated patients, phenylketonuria (PKU) results in severe encephalopathy with mental retardation. A protein-restricted diet is recommended which can be relaxed in adolescence/adulthood. METHODS: We contacted all 72 adult/adolescent PKU patients who had been treated in our center during early childhood. Some still regularly attended our outpatient clinics, while others were lost for follow-up, giving 51 patients in our study. We asked all patients to complete a dietary protocol as well as a questionnaire on quality of life. Blood and urine were analyzed and body impedance plethysmography and cerebral MRI were performed. RESULTS: 42 % of the patients followed protein restriction supplemented with amino acid mixtures (AAM), others had a vegan diet with (8 %) or without (14 %) AAM; 36 % said they were eating normally and did not need any AAM. However, based on dietary protocols and blood urea levels, protein intake was restricted in this patient group. None of the patients examined had serious nutritional deficits. Phenylalanine levels were higher in patients not taking AAM. MRI of the brain was not different from those following protein restriction and taking AAM. The lesions score and mood correlated best with the cumulative phenylalanine values during the first 10 years of life. CONCLUSION: In summary, 50 % of adult/adolescent patients from our center did not take AAM at the start of our survey although they unknowingly followed self-imposed protein restriction. They had no overt nutritional deficits; however, long-term brain function may be compromised. Our study emphasizes the need for specialized metabolic care in PKU during adulthood.
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OBJECTIVE: 3-Methylglutaconic aciduria type I is a rare inborn error of leucine catabolism. It is thought to present in childhood with nonspecific symptoms; it was even speculated to be a nondisease. The natural course of disease is unknown. METHODS: This is a study on 10 patients with 3-methylglutaconic aciduria type I. We present the clinical, neuroradiologic, biochemical, and genetic details on 2 new adult-onset patients and follow-up data on 2 patients from the literature. RESULTS: Two unrelated patients with the characteristic biochemical findings of 3- methylglutaconic aciduria type I presented in adulthood with progressive ataxia. One patient additionally had optic atrophy, the other spasticity and dementia. Three novel mutations were found in conserved regions of the AUH gene. In both patients, MRI revealed extensive white matter disease. Follow-up MRI in a 10-year-old boy, who presented earlier with isolated febrile seizures, showed mild abnormalities in deep white matter. CONCLUSION: We define 3-methylglutaconic aciduria type I as an inborn error of metabolism with slowly progressive leukoencephalopathy clinically presenting in adulthood. In contrast to the nonspecific findings in pediatric cases, the clinical and neuroradiologic pattern in adult patients is highly characteristic. White matter abnormalities may already develop in the first decades of life. The variable features found in affected children may be coincidental. Long-term follow-up in children is essential to learn more about the natural course of this presumably slowly progressive disease. Dietary treatment with leucine restriction may be considered.
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Errores Innatos del Metabolismo de los Aminoácidos/patología , Encefalopatías Metabólicas Innatas/patología , Encéfalo/patología , Glutaratos/metabolismo , Leucina/metabolismo , Leucoencefalopatías/patología , Fibras Nerviosas Mielínicas/patología , Adulto , Errores Innatos del Metabolismo de los Aminoácidos/genética , Errores Innatos del Metabolismo de los Aminoácidos/metabolismo , Encéfalo/metabolismo , Encefalopatías Metabólicas Innatas/genética , Encefalopatías Metabólicas Innatas/metabolismo , Mapeo Encefálico , Niño , Progresión de la Enfermedad , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Lactante , Leucoencefalopatías/genética , Leucoencefalopatías/metabolismo , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Fibras Nerviosas Mielínicas/metabolismoRESUMEN
The aim of the study was to develop a method for fast and reliable diagnosis of peroxisomal diseases and to facilitate differential diagnosis of cholestatic hepatopathy. For the quantification of bile acids and their conjugates as well as C(27) precursors di- and trihydroxycholestanoic acid (DHCA, THCA), in small pediatric blood samples we combined HPLC separation on a reverse-phase C18 column with ESI-MS/MS analysis in the negative ion mode. Analysis was done with good precision (CV 3,7%-11.1%) and sufficient sensitivity (LOQ: 11-91 nmol/L) without derivatization. Complete analysis of 17 free and conjugated bile acids from dried blood spots and 10 microL serum samples, respectively, was performed within 12 min. Measurement of conjugated primary bile acids plus DHCA and THCA as well as ursodeoxycholic acid was done in 4.5 min. In blood spots of healthy newborns, conjugated primary bile acids were found in the range of 0.01 to 2.01 micromol/L. Concentrations of C(27) precursors were below the detection limit in normal controls. DHCA and THCA were specifically elevated in cases of peroxysomal defects and one Zellweger patient.
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Ácidos y Sales Biliares/sangre , Ácidos y Sales Biliares/química , Análisis Químico de la Sangre/métodos , Recolección de Muestras de Sangre , Carbono/química , Suero/química , Atresia Biliar/sangre , Cromatografía Liquida , Galactosemias/sangre , Humanos , Lactante , Recién Nacido , Modelos Lineales , Trastorno Peroxisomal/sangre , Espectrometría de Masas en Tándem , Factores de Tiempo , Ácido Ursodesoxicólico/uso terapéuticoRESUMEN
Fabry disease, also known as Anderson-Fabry disease, is an X-linked lysosomal storage disorder. The clinical picture is highly variable and usually milder in females. It is a multisystemic disease involving many organs. Fabry disease is due to a deficiency of alpha-galactosidase A caused by different usually "private" mutations. Enzyme replacement therapy (ERT) has been established, other therapeutic options are at an experimental stage. Classically, mechanical deposition of storage material in blood vessels was believed to lead to decreased blood supply with consecutive organ dysfunction. Recently, however, many secondary biochemical processes have been discussed to be involved in the pathogenesis of Fabry disease. For example, compromised energy metabolism has been found both in vitro and in vivo, altered lipid composition of membranes can lead to abnormalities in trafficking and sorting of rafts-associated proteins. We discuss the role of these secondary phenomena in the pathogenesis of Fabry disease.
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Enfermedad de Fabry/metabolismo , Mitocondrias/fisiología , Terapia de Reemplazo Enzimático , Enfermedad de Fabry/diagnóstico , Enfermedad de Fabry/fisiopatología , Enfermedad de Fabry/terapia , Femenino , Humanos , Masculino , Transporte de Proteínas , alfa-Galactosidasa/uso terapéuticoRESUMEN
Hurler-Scheie syndrome is caused by alpha-l-iduronidase deficiency. Enzyme replacement therapy (ERT) can improve physical capacity and reduces organomegaly. However, the effect on bradytrophic connective tissue is limited. As intravenously administered enzyme cannot cross the blood-brain barrier, the therapy of choice for the more severe Hurler syndrome is haematopoietic stem cell transplantation (HCT). In the more attenuated Scheie syndrome, neurological impairment is less severe; therefore, ERT may be appropriate to treat these patients. Information on long-term outcome in Scheie patients undergoing ERT is scarce. We report a 38-year-old female Scheie patient who has been on ERT for 8 years. While non-neurological symptoms improved, she developed paresthesias in her hands and feet and progressive pain in her legs. Somatosensory evoked potentials were abnormal, suggesting dysfunction of the dorsal funiculus and lemniscus medialis. After 6 years of ERT, a spinal MRI showed dural thickening at the upper cervical spine. These soft-tissue deposits are presumably due to the accumulation of mucopolysaccharides. Intramedullary hyperintensities at the level of C1/2 revealed cervical myelopathy. An MRI before the start of ERT had shown milder spinal lesions. Cystic lesions in the white matter of the centrum semiovale due to dilated Virchow-Robin spaces were essentially unchanged compared with the MRI scan before ERT. Decompression of the spinal cord resulted in clinical improvement. In an adult patient with Scheie syndrome, ERT failed to prevent progression of cervical myelopathy. Clinical significance of cerebral changes is unclear. Whether early HCT or intrathecal ERT could have prevented these lesions remains speculative.
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Terapia de Reemplazo Enzimático , Iduronidasa/uso terapéutico , Mucopolisacaridosis I/complicaciones , Mucopolisacaridosis I/tratamiento farmacológico , Compresión de la Médula Espinal/etiología , Adulto , Encéfalo/patología , Vértebras Cervicales , Progresión de la Enfermedad , Femenino , Trasplante de Células Madre Hematopoyéticas , Humanos , Mucopolisacaridosis I/fisiopatología , Compresión de la Médula Espinal/patología , Compresión de la Médula Espinal/fisiopatologíaRESUMEN
Objectives Isolated methylmalonic acidurias (MMAurias) are caused by deficiency of methylmalonyl-CoA mutase or by defects in the synthesis of its cofactor 5'-deoxyadenosylcobalamin. The aim of this study was to evaluate which parameters best predicted the long-term outcome. Methods Standardized questionnaires were sent to 20 European metabolic centres asking for age at diagnosis, birth decade, diagnostic work-up, cobalamin responsiveness, enzymatic subgroup (mut(0), mut(-), cblA, cblB) and different aspects of long-term outcome. Results 273 patients were included. Neonatal onset of the disease was associated with increased mortality rate, high frequency of developmental delay, and severe handicap. Cobalamin non-responsive patients with neonatal onset born in the 1970s and 1980s had a particularly poor outcome. A more favourable outcome was found in patients with late onset of symptoms, especially when cobalamin responsive or classified as mut(-). Prevention of neonatal crises in pre-symptomatically diagnosed newborns was identified as a protective factor concerning handicap. Chronic renal failure manifested earlier in mut(0) patients than in other enzymatic subgroups. Conclusion Outcome in MMAurias is best predicted by the enzymatic subgroup, cobalamin responsiveness, age at onset and birth decade. The prognosis is still unfavourable in patients with neonatal metabolic crises and non-responsiveness to cobalamin, in particular mut(0) patients.
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Errores Innatos del Metabolismo de los Aminoácidos/diagnóstico , Biomarcadores/análisis , Metilmalonil-CoA Mutasa/deficiencia , Adolescente , Adulto , Edad de Inicio , Errores Innatos del Metabolismo de los Aminoácidos/epidemiología , Errores Innatos del Metabolismo de los Aminoácidos/genética , Errores Innatos del Metabolismo de los Aminoácidos/mortalidad , Niño , Preescolar , Cobamidas/deficiencia , Estudios de Cohortes , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Metilmalonil-CoA Mutasa/genética , Evaluación de Resultado en la Atención de Salud , Pronóstico , Análisis de Supervivencia , Adulto JovenRESUMEN
To further substantiate gestational age-related changes in oxalate excretion, we studied urinary oxalate excretion in 66 preterm infants born at 23.4-34.7 weeks of gestation. Spot urine of 66 preterm infants was analysed by ion chromatography as soon as they were completely orally fed with enriched breast milk and/or special preterm milk formula (days 7 to 57 of postnatal life). Infants with evidence of renal, gastrointestinal, muscular or metabolic disease were not included. Newborns on parenteral nutrition were excluded. Oxalate/creatinine ratios (Ox/Cr) decreased with gestational age (three age groups: group 1, 23 0/7-28 0/7; group 2, 28 1/7-32 0/7; and group 3, 32 1/7-35 0/7 weeks of gestation). The mean Ox/Cr was highest in group 1 (398.2 mmol/mol +/- 116.8; n = 21). Differences between groups 1 + 3 were statistically significant; p = 0.001; those between groups 1 + 2 and between groups 2 + 3 were not. Ox/Cr correlated inversely with gestational and maturational age (r = -0.41, p = 0.001; r = -0.33, p = 0.007) and positively with postnatal age (r = 0.32, p = 0.008). It correlated inversely with birth weight as well as actual weight at sample collection (r = -0.46 and -0.44, p < 0.001). Ox/Cr was significantly linked to energy and carbohydrate intake (r = 0.3 and 0.4, p = 0.03 and 0.001). These results were independent of sex. In the present study we show that urinary oxalate excretion in preterm infants depends on gestational age.
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Desarrollo Infantil/fisiología , Nutrición Enteral , Trastornos de la Nutrición del Lactante/terapia , Recien Nacido Prematuro/orina , Ácido Oxálico/orina , Estudios de Cohortes , Creatinina/orina , Ingestión de Energía/fisiología , Femenino , Edad Gestacional , Humanos , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido , Recien Nacido Prematuro/crecimiento & desarrollo , Recien Nacido Prematuro/fisiología , Masculino , Factores de TiempoRESUMEN
OBJECTIVE: In patients with severe urea cycle defects (UCD) metabolic decompensation with hyperammonaemia typically occurs during the first days of life resulting in severe neurological damage or death. Benzoate can eliminate nitrogen independent of the urea cycle. Usually, benzoate is started soon after birth, but prenatal administration might improve metabolic stability. DESIGN: Two fetuses with a prenatal diagnosis of UCD (female: citrullinaemia; male: ornithine transcarbamylase deficiency) were loaded with benzoate prenatally via the placenta by infusing their mothers with benzoate. Benzoate concentrations were measured in umbilical cord blood and the blood of the mothers and their newborns. RESULTS: Therapeutic concentrations of benzoate were found in umbilical cord blood and in the children's blood. Thus, benzoate transfer across the placenta was demonstrated. Plasma ammonia and glutamine levels in the postnatal period were within the normal range. CONCLUSIONS: Benzoate infusion of the mother shortly before birth is safe and results in therapeutic levels of benzoate in umbilical cord blood.
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Citrulinemia/tratamiento farmacológico , Enfermedad por Deficiencia de Ornitina Carbamoiltransferasa/tratamiento farmacológico , Benzoato de Sodio/administración & dosificación , Femenino , Sangre Fetal/química , Humanos , Recién Nacido , Masculino , Embarazo , Atención Prenatal/métodos , Diagnóstico Prenatal , Benzoato de Sodio/sangre , Factores de Tiempo , Resultado del TratamientoRESUMEN
Recent studies have challenged the conventional hypothesis that inflammation is the major player in the fibrosis cascade. Emerging evidence points to a critical role for interactions between tissue-resident and infiltrating, non-resident cells, in mediating fibrotic responses. Improved understanding of the biology of extracellular matrix (ECM) remodeling and the pathways that regulate assembly of the ECM and its interactions with growth factors/cytokines have led to the identification of new and attractive therapeutic targets. These include molecules that regulate fibrocytic cell infiltration, epithelial and myofibroblast differentiation, ECM synthesis and degradation. However, it is imperative that these new therapies be timed and compartmentalized to target the tissue of interest, as the dynamics of cellular differentiation and ECM remodeling may be different between organ systems. This review will summarize the current understanding of the mechanisms involved in the development of fibrosis, based on recent in vitro and in vivo studies, and comment on novel molecular pathways for drug discovery.
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Fibrosis , Inflamación/complicaciones , Animales , Quimiocinas/fisiología , Enfermedad Crónica , Citocinas/fisiología , Descubrimiento de Drogas , Células Epiteliales/citología , Fibrosis/tratamiento farmacológico , Fibrosis/etiología , Humanos , Péptidos y Proteínas de Señalización Intercelular/fisiología , Mesodermo/citología , Células Madre/fisiología , Factor de Crecimiento Transformador beta/fisiologíaRESUMEN
The long-term outcome of patients with methylmalonic aciduria (MMA) is still uncertain due to a high frequency of complications such as chronic renal failure and metabolic stroke. The understanding of this disease is hampered by a huge variation in the management of these patients. The major aim of this study was to evaluate the current practice in different European metabolic centres. A standardized questionnaire was sent to 20 metabolic centres asking for standard procedures for confirmation of diagnosis, testing cobalamin responsiveness, dietary treatment, pharmacotherapy, and biochemical and clinical monitoring. Sixteen of 20 metabolic centres (80%) returned questionnaires on 183 patients: 89 of the patients were classified as mut(0), 36 as mut(-), 13 as cblA, 7 as cblB, and 38 as cblA/B. (1) Confirmation of diagnosis: All centres investigate enzyme activity by propionate fixation in fibroblasts; six centres also perform mutation analysis. (2) Cobalamin response: Ten centres follow standardized protocols showing large variations. A reliable exclusion of nonspecific effects has not yet been achieved by these protocols. (3) Long-term treatment: In cobalamin-responsive patients, most centres use hydroxocobalamin (1-14 mg/week i.m. or 5-20 mg/week orally), while two centres use cyanocobalamin. All cobalamin-nonresponsive patients and most cobalamin-responsive patients are supplemented with L: -carnitine (50-100 mg/kg per day). Fourteen centres use intestinal decontamination by antibiotic therapy. Most centres follow D-A-CH (n = 6) or Dewey (n = 4) recommendations for protein requirements. Fourteen centres regularly use precursor-free amino acid supplements. Standardized monitoring protocols are available in seven centres, again showing high variability.
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Errores Innatos del Metabolismo de los Aminoácidos/diagnóstico , Ácido Metilmalónico/orina , Adolescente , Adulto , Errores Innatos del Metabolismo de los Aminoácidos/tratamiento farmacológico , Niño , Preescolar , Humanos , Hidroxocobalamina/uso terapéutico , Lactante , Recién Nacido , Vitamina B 12/uso terapéuticoRESUMEN
Amyloid precursor protein (APP) and amyloid beta-peptide (Abeta) have been implicated in a variety of physiological and pathological processes underlying nervous system functions. APP shares many features with adhesion molecules in that it is involved in neurite outgrowth, neuronal survival and synaptic plasticity. It is, thus, of interest to identify binding partners of APP that influence its functions. Using biochemical cross-linking techniques we have identified ATP synthase subunit alpha as a binding partner of the extracellular domain of APP and Abeta. APP and ATP synthase colocalize at the cell surface of cultured hippocampal neurons and astrocytes. ATP synthase subunit alpha reaches the cell surface via the secretory pathway and is N-glycosylated during this process. Transfection of APP-deficient neuroblastoma cells with APP results in increased surface localization of ATP synthase subunit alpha. The extracellular domain of APP and Abeta partially inhibit the extracellular generation of ATP by the ATP synthase complex. Interestingly, the binding sequence of APP and Abeta is similar in structure to the ATP synthase-binding sequence of the inhibitor of F1 (IF(1)), a naturally occurring inhibitor of the ATP synthase complex in mitochondria. In hippocampal slices, Abeta and IF(1) similarly impair both short- and long-term potentiation via a mechanism that could be suppressed by blockade of GABAergic transmission. These observations indicate that APP and Abeta regulate extracellular ATP levels in the brain, thus suggesting a novel mechanism in Abeta-mediated Alzheimer's disease pathology.
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Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , ATPasas de Translocación de Protón Mitocondriales/metabolismo , Adenosina Trifosfato/biosíntesis , Precursor de Proteína beta-Amiloide/genética , Animales , Biotinilación/métodos , Encéfalo/ultraestructura , Células Cultivadas , Relación Dosis-Respuesta a Droga , Femenino , Antagonistas del GABA/farmacología , Corazón/efectos de los fármacos , Hipocampo/citología , Humanos , Inmunoprecipitación/métodos , Potenciación a Largo Plazo/efectos de los fármacos , Potenciación a Largo Plazo/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , ATPasas de Translocación de Protón Mitocondriales/farmacocinética , Neuroblastoma , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Péptido-N4-(N-acetil-beta-glucosaminil) Asparagina Amidasa/farmacología , Picrotoxina/farmacología , Unión Proteica/efectos de los fármacos , Unión Proteica/fisiología , Transporte de Proteínas/fisiología , Ratas , Transfección/métodosRESUMEN
BACKGROUND: We aimed to study the reproducibility of several biomarkers of allergic rhinitis to investigate their potential as outcome measures in clinical intervention trials. Furthermore, we investigated the kinetics of the biomarkers studied in nasal lavage and brush material following a placebo-controlled nasal allergen challenge. METHODS: We performed a skin prick test and measured serum specific immunoglobulin (Ig) E levels and inflammatory biomarkers in nasal lavage and brush material in 20 patients with allergic rhinitis on 2 separate days (washout, 14-21 days). The patients were then randomly assigned to undergo an intranasal challenge with a relevant allergen (n=10) or diluent (n=10) in order to assess the kinetics of several biomarkers of allergic airway inflammation in nasal lavage and brush samples. RESULTS: Baseline serum IgE levels and skin wheal sizes were highly reproducible measurements, with a coefficient of variation (CV) of 13.4% and 18.2%, respectively. This was not the case with the majority of inflammatory biomarkers, whose CV varied considerably (range, 6.1%-224.1%). The nasal allergen challenge induced an increase in composite symptom scores in all patients. Compared to placebo, tryptase (P=.004), eosinophilic cationic protein (ECP) (P=.03) and alpha2-macroglobulin (P=.002) were increased in nasal lavage at 20 minutes post allergen. Nasal lavage ECP levels and nasal brush eosinophils were still significantly increased at 7 hours (P=.03 and P=.04), but all statistical significance had been lost at 24 hours post challenge. CONCLUSION: Serum specific IgE assays and skin prick tests exhibited good reproducibility in patients with clinically stable allergic rhinitis. We were also able to investigate the kinetics of allergen-induced upper airway inflammatory markers in nasal lavage and brush material. Hence, nasal allergen challenge, when used in combination with nasal lavage and brush sampling, is a suitable research tool for early drug development.
Asunto(s)
Antiinflamatorios/uso terapéutico , Rinitis Alérgica Perenne/tratamiento farmacológico , Rinitis Alérgica Estacional/tratamiento farmacológico , Adulto , Alérgenos/inmunología , Biomarcadores/sangre , Femenino , Humanos , Inmunoglobulina E/sangre , Masculino , Persona de Mediana Edad , Líquido del Lavado Nasal/inmunología , Pruebas de Provocación Nasal , Nariz/inmunología , Reproducibilidad de los Resultados , Rinitis Alérgica Perenne/sangre , Rinitis Alérgica Estacional/sangre , Pruebas CutáneasRESUMEN
Alexander disease is a rare disorder of cerebral white matter due to a dysfunction of astrocytes. The most common infantile form presents as a megalencephalic leukodystrophy. Mutations of the GFAP gene, encoding Glial Fibrillary Acidic Protein, have been recognized as the cause of Alexander disease. Glial Fibrillary Acidic Protein is the major intermediate filament protein in astrocytes, its functional rod domain is conserved in sequence and structure among other intermediate filament proteins. We report here two cases of infantile Alexander disease with early onset and severe course, caused by DE NOVO mutations A364 V and Y366C. Both affected GFAP residues are part of a highly conserved coiled-coil trigger motif in the C-terminal end of segment 2B, probably required for the stability of intermediate filament molecules. Comparable effects are seen with mutations of the corresponding residues of the gene coding for keratin 14, another intermediate filament, this further supports the hypothesis that these positions of the trigger motif are generally critical for a normal function of intermediate filaments.
Asunto(s)
Enfermedad de Alexander/genética , Exones/genética , Proteína Ácida Fibrilar de la Glía/genética , Mutación/genética , Edad de Inicio , Alanina/genética , Enfermedad de Alexander/patología , Cisteína/genética , Análisis Mutacional de ADN/métodos , Femenino , Lóbulo Frontal/patología , Humanos , Lactante , Imagen por Resonancia Magnética/métodos , Masculino , Estructura Terciaria de Proteína/genética , Tirosina/genética , Valina/genéticaRESUMEN
BACKGROUND: Symptoms of Vitamin B (12) deficiency in infancy include growth retardation, regression of psychomotor development, muscular hypotonia and brain atrophy. Besides an inappropriate vegetarian diet of the infants, a vegan diet or a pernicious anaemia of the mother may lead to an insufficient vitamin B (12) supply of the child. PATIENTS AND METHODS: We report here the neurological symptoms of 4 fully breast-fed infants from mothers on vegan diet or with pernicious anaemia. DISCUSSION AND CONCLUSION: Vitamin B (12) deficiency can easily be diagnosed by detection of methylmalonic acid when measuring the organic acids in urine. Vitamin B (12) deficiency should be avoided or diagnosed as early as possible since a supplementation of mother and child can prevent neurological symptoms of the baby. Furthermore, the neurological symptoms of the infant with manifest vitamin B (12) deficiency are (partially) reversible.