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1.
BMC Pediatr ; 22(1): 335, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35689179

RESUMO

BACKGROUND: Neonatal Emergency Transport Services play a fundamental role in neonatal care. Stabilization before transport of newborns suffering from severe respiratory failure is often a challenging problem and some critically ill infants may benefit from High Frequency Oscillatory Ventilation (HFOV) as rescue treatment. In these cases, transition to conventional ventilation for transport may cause a deterioration in clinical conditions. HFOV during neonatal transport has been only exceptionally used, due to technical difficulties. Since May 2018, a new neonatal transport unit is available at the Neonatal Protected Transport Service of the Meyer University Hospital in Florence, equipped with a pulmonary ventilator capable of delivering HFOV. Therefore, we conducted an analysis on patients transferred in HFOV to Neonatal Intensive Care Unit (NICU), in order to evaluate the safety and feasibility of its use during neonatal transport. METHODS: A retrospective analysis was performed reviewing medical records of the neonates transported by Meyer Children Hospital's Neonatal Transport Service between May 2018 and December 2020, and newborns treated with HFOV during ground neonatal transport were identified. Safety was assessed by the comparison of vital signs, hemogas-analysis values and pulmonary ventilator parameters, at the time of departure and upon arrival in NICU. The dose of inotropes, the main respiratory complications (air leak, dislocation or obstruction of the endotracheal tube, loss of chest vibrations) and the number of deaths and transfer failures were recorded. RESULTS: Out of the approximate 400 newborns transported during the analysis period, 9 were transported in HFOV. We did not find any statistically significant difference in vital parameters, hemogas-analytical values and pulmonary ventilator settings recorded before and after neonatal transport of the nine patients' parameters (p > 0,05). No patient required additional inotropes during transport. No transport-related deaths or significant complications occurred during transport. CONCLUSIONS: The interest of our report is in the possibility of using HFOV during inter-hospital neonatal transfer. As far as our experience has shown, HFOV appears to be safe for the transportation of newborns with severe respiratory failure. Nevertheless, further larger, prospective and multicentre studies are needed to better evaluate the safety and efficacy of HFOV during neonatal transport.


Assuntos
Ventilação de Alta Frequência , Síndrome do Desconforto Respiratório do Recém-Nascido , Insuficiência Respiratória , Criança , Humanos , Lactente , Recém-Nascido , Dados Preliminares , Estudos Prospectivos , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Insuficiência Respiratória/terapia , Estudos Retrospectivos
2.
Mol Genet Metab ; 129(2): 47-58, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31711734

RESUMO

Lysosomal storage diseases (LSDs) are rare to extremely rare monogenic disorders. Their incidence, however, has probably been underestimated owing to their complex clinical manifestations. Sialidosis is a prototypical LSD inherited as an autosomal recessive trait and caused by mutations in the NEU1 gene that result in a deficiency of alpha-N-acetyl neuraminidase 1 (NEU1). Two basic forms of this disease, type I and type II, are known. The dysmorphic type II form features LSD symptoms including congenital hydrops, dysmorphogenetic traits, hepato-splenomegaly and severe intellectual disability. The diagnosis is more challenging in the normosomatic type I forms, whose clinical findings at onset include ocular defects, ataxia and generalized myoclonus. Here we report the clinical, biochemical and molecular analysis of five patients with sialidosis type I. Two patients presented novel NEU1 mutations. One of these patients was compound heterozygous for two novel NEU1 missense mutations: c.530A>T (p.Asp177Val) and c.1010A>G (p.His337Arg), whereas a second patient was compound heterozygous for a known mutation and a novel c.839G>A (p.Arg280Gln) mutation. We discuss the impact of these new mutations on the structural properties of NEU1. We also review available clinical reports of patients with sialidosis type I, with the aim of identifying the most frequent initial clinical manifestations and achieving more focused diagnoses.


Assuntos
Ataxia/diagnóstico , Mucolipidoses/diagnóstico , Mucolipidoses/genética , Mioclonia/diagnóstico , Neuraminidase/genética , Adolescente , Adulto , Criança , Diagnóstico Diferencial , Feminino , Humanos , Lisossomos/patologia , Mutação de Sentido Incorreto , Fenótipo , Adulto Jovem
3.
J Med Genet ; 52(6): 405-12, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25755106

RESUMO

BACKGROUND: Loss-of-function mutations of the FLNA gene cause a neuronal migration disorder defined as X-linked periventricular nodular heterotopia (PNH); gain-of-function mutations are associated with a group of X-linked skeletal dysplasias designed as otopalatodigital (OPD) spectrum. We describe a family in which a woman and her three daughters exhibited a complex phenotype combining PNH, epilepsy and Melnick-Needles syndrome (MNS), a skeletal disorder assigned to the OPD spectrum. All four individuals harboured a novel non-conservative missense mutation in FLNA exon 3. METHODS: In all affected family members, we performed mutation analysis of the FLNA gene, RT-PCR, ultradeep sequencing analysis in FLNA cDNAs and western blot in lymphocyte cells to further characterise the mutation. We also assessed the effects on RT-PCR products of treatment of patients' lymphocytes with cycloheximide, a nonsense mediated mRNA decay (NMD) inhibitor. RESULTS: We identified a novel c.622G>C change in FLNA exon 3, leading to the substitution of a highly conserved aminoacid (p.Gly208Arg). Gel electrophoresis and ultradeep sequencing revealed the missense mutation as well as retention of intron 3. Cycloheximide treatment demonstrated that the aberrant mRNA transcript-retaining intron 3 is subjected to NMD. Western blot analysis confirmed reduced FLNA levels in lymphocyte cells. CONCLUSIONS: The novel c.622G>C substitution leads to two aberrant FLNA transcripts, one of which carries the missense mutation, plus a longer transcript resulting from intron 3 retention. We propose that the exceptional co-occurrence of PNH and MNS, two otherwise mutually exclusive allelic phenotypes, is the consequence of a single mutational event resulting in co-occurring gain-of-function and loss-of-function effects.


Assuntos
Epilepsia/genética , Filaminas/genética , Estudos de Associação Genética , Mutação , Osteocondrodisplasias/genética , Heterotopia Nodular Periventricular/genética , Sequência de Bases , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Encéfalo/patologia , Biologia Computacional , Análise Mutacional de DNA , Éxons , Feminino , Filaminas/química , Filaminas/metabolismo , Genes Ligados ao Cromossomo X , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Linfócitos/metabolismo , Imageamento por Ressonância Magnética , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Degradação do RNAm Mediada por Códon sem Sentido , Osteocondrodisplasias/diagnóstico , Linhagem , Heterotopia Nodular Periventricular/diagnóstico , Splicing de RNA , Radiografia , Alinhamento de Sequência , Síndrome , Inativação do Cromossomo X
4.
Hum Mutat ; 36(3): 357-68, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25545067

RESUMO

Morquio A syndrome (MPS IVA) is a systemic lysosomal storage disorder caused by the deficiency of N-acetylgalactosamine-6-sulfatase (GALNS), encoded by the GALNS gene. We studied 37 MPS IV A patients and defined genotype-phenotype correlations based on clinical data, biochemical assays, molecular analyses, and in silico structural analyses of associated mutations. We found that standard sequencing procedures, albeit identifying 14 novel small GALNS genetic lesions, failed to characterize the second disease-causing mutation in the 16% of the patients' cohort. To address this drawback and uncover potential gross GALNS rearrangements, we developed molecular procedures (CNV [copy-number variation] assays, QF-PCRs [quantitative fluorescent-PCRs]), endorsed by CGH-arrays. Using this approach, we characterized two new large deletions and their corresponding breakpoints. Both deletions were heterozygous and included the first exon of the PIEZO1 gene, which is associated with dehydrated hereditary stomatocitosis, an autosomal-dominant syndrome. In addition, we characterized the new GALNS intronic lesion c.245-11C>G causing m-RNA defects, although identified outside the GT/AG splice pair. We estimated the occurrence of the disease in the Italian population to be approximately 1:300,000 live births and defined a molecular testing algorithm designed to help diagnosing MPS IVA and foreseeing disease progression.


Assuntos
Condroitina Sulfatases/genética , Mucopolissacaridose IV/diagnóstico , Mucopolissacaridose IV/genética , Mutação , RNA Mensageiro/genética , Adolescente , Adulto , Linhagem Celular , Condroitina Sulfatases/química , Feminino , Fibroblastos , Humanos , Linfócitos , Masculino , Fenótipo , Prognóstico , Isoformas de Proteínas/genética , Pele/citologia , Adulto Jovem
5.
Chembiochem ; 16(14): 2054-64, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26376302

RESUMO

A collection of carbohydrate-derived iminosugars belonging to three structurally diversified sub-classes (polyhydroxylated pyrrolidines, piperidines, and pyrrolizidines) was evaluated for inhibition of human acid ß-glucosidase (glucocerebrosidase, GCase), the deficient enzyme in Gaucher disease. The synthesis of several new pyrrolidine analogues substituted at the nitrogen or α-carbon atom with alkyl chains of different lengths suggested an interpretation of the inhibition data and led to the discovery of two new GCase inhibitors at sub-micromolar concentration. In the piperidine iminosugar series, two N-alkylated derivatives were found to rescue the residual GCase activity in N370S/RecNcil mutated human fibroblasts (among which one up to 1.5-fold). This study provides the starting point for the identification of new compounds in the treatment of Gaucher disease.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Doença de Gaucher/enzimologia , Glucosilceramidase/antagonistas & inibidores , Imino Açúcares/química , Imino Açúcares/farmacologia , Descoberta de Drogas , Doença de Gaucher/tratamento farmacológico , Glucosilceramidase/metabolismo , Humanos
6.
ScientificWorldJournal ; 2013: 625824, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24294134

RESUMO

Medium-chain acyl-CoA dehydrogenase deficiency (MCADD) is a disorder of fatty acid oxidation characterized by hypoglycemic crisis under fasting or during stress conditions, leading to lethargy, seizures, brain damage, or even death. Biochemical acylcarnitines data obtained through newborn screening by liquid chromatography-tandem mass spectrometry (LC-MS/MS) were confirmed by molecular analysis of the medium-chain acyl-CoA dehydrogenase (ACADM) gene. Out of 324.000 newborns screened, we identified 14 MCADD patients, in whom, by molecular analysis, we found a new nonsense c.823G>T (p.Gly275∗) and two new missense mutations: c.253G>C (p.Gly85Arg) and c.356T>A (p.Val119Asp). Bioinformatics predictions based on both phylogenetic conservation and functional/structural software were used to characterize the new identified variants. Our findings confirm the rising incidence of MCADD whose existence is increasingly recognized due to the efficacy of an expanded newborn screening panel by LC-MS/MS making possible early specific therapies that can prevent possible crises in at-risk infants. We noticed that the "common" p.Lys329Glu mutation only accounted for 32% of the defective alleles, while, in clinically diagnosed patients, this mutation accounted for 90% of defective alleles. Unclassified variants (UVs or VUSs) are especially critical when considering screening programs. The functional and pathogenic characterization of genetic variants presented here is required to predict their medical consequences in newborns.


Assuntos
Acil-CoA Desidrogenase/deficiência , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Testes Genéticos/estatística & dados numéricos , Erros Inatos do Metabolismo Lipídico/diagnóstico , Erros Inatos do Metabolismo Lipídico/genética , Triagem Neonatal/métodos , Modelos de Riscos Proporcionais , Acil-CoA Desidrogenase/genética , Feminino , Humanos , Incidência , Recém-Nascido , Itália/epidemiologia , Erros Inatos do Metabolismo Lipídico/epidemiologia , Masculino , Polimorfismo de Nucleotídeo Único/genética , Reprodutibilidade dos Testes , Medição de Risco , Sensibilidade e Especificidade
7.
Acta Biomed ; 94(S1): e2023097, 2023 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-36883684

RESUMO

Background and aim Myotonic dystrophy (DM) is a genetic disorder determined by an amplified trinucleotide CTG repeat in the untranslated region of the DMPK gene on chromosome 19q13.3. The incidence of the congenital form is 1 in 47619 live births and the mortality in the neonatal period is up to 40%. Methods: We report a case of congenital DM (CDM, also designated Myotonic Dystrophy Type 1), presented with congenital right diaphragmatic hernia and cerebral bilateral ventricular dilatation, genetically diagnosed. Conclusions: Since no case of congenital diaphragmatic hernia associated with CDM is reported, the present case report could be considered of particular interest.


Assuntos
Hérnias Diafragmáticas Congênitas , Distrofia Miotônica , Humanos , Recém-Nascido , Hérnias Diafragmáticas Congênitas/genética , Distrofia Miotônica/complicações , Distrofia Miotônica/diagnóstico , Distrofia Miotônica/genética
8.
Biochim Biophys Acta ; 1810(4): 446-56, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21256191

RESUMO

BACKGROUND: Sphingosine 1-phosphate (S1P) is a sphingolipid metabolite synthesized after stimulation with growth factors or cytokines. S1P extracellular effects are mediated through specific Gi-protein coupled receptors (GPCRs). Recently, we demonstrated in NIH3T3 fibroblasts stimulated by platelet-derived growth factor (PDGF) or S1P the NADPH oxidase activation and the H(2)O(2) intracellular level increase trough the Gi protein involvement. METHODS: NIH3T3 fibroblast cell cultures were used. Western blot and quantitative analyses by Chemidoc-Quantity-One software were performed. H(2)O(2) level was assayed by fluorescence spectrophotometric analysis, and cell proliferation by counted manually or ELISA kit. RESULTS: This study demonstrates, in NIH 3T3 fibroblasts, a novel redox regulated mechanism of S1P-induced activation of ERK 1/2 related to NADPH oxidase activity and intracellular H(2)O(2) level increase with PDGF receptor tyrosine kinase involvement through a transactivation mechanism. This event is mediated by S1P(1) and S1P(3) receptors by Gi proteins and can contribute to S1P mitogenic signaling. CONCLUSION: These results can be related to mechanisms of cross-talk previously identified between receptor tyrosine kinase, including PDGFreceptor, and several GPCR ligands. GENERAL SIGNIFICANCE: The redox-sensitive ERK1/2 and PDGFr tyrosine kinase activity could be targets for therapies in diseases in which deregulation of intracellular oxidative status and the consequent alteration of S1P and/or PDGF signaling pathway are involved.


Assuntos
Fibroblastos/metabolismo , Lisofosfolipídeos/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , NADPH Oxidases/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Esfingosina/análogos & derivados , Animais , Proliferação de Células , Fibroblastos/citologia , Peróxido de Hidrogênio/metabolismo , Camundongos , Células NIH 3T3 , Oxirredução , Esfingosina/metabolismo
9.
Biochim Biophys Acta ; 1812(7): 782-90, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21497194

RESUMO

GM1 gangliosidosis and Morquio B syndrome, both arising from beta-galactosidase (GLB1) deficiency, are very rare lysosomal storage diseases with an incidence of about 1:100,000-1:200,000 live births worldwide. Here we report the beta-galactosidase gene (GLB1) mutation analysis of 21 unrelated GM1 gangliosidosis patients, and of 4 Morquio B patients, of whom two are brothers. Clinical features of the patients were collected and compared with those in literature. In silico analyses were performed by standard alignments tools and by an improved version of GLB1 three-dimensional models. The analysed cohort includes remarkable cases. One patient with GM1 gangliosidosis had a triple X syndrome. One patient with juvenile GM1 gangliosidosis was homozygous for a mutation previously identified in Morquio type B. A patient with infantile GM1 gangliosidosis carried a complex GLB1 allele harbouring two genetic variants leading to p.R68W and p.R109W amino acid changes, in trans with the known p.R148C mutation. Molecular analysis showed 27 mutations, 9 of which are new: 5 missense, 3 microdeletions and a nonsense mutation. We also identified four new genetic variants with a predicted polymorphic nature that was further investigated by in silico analyses. Three-dimensional structural analysis of GLB1 homology models including the new missense mutations and the p.R68W and p.R109W amino acid changes showed that all the amino acid replacements affected the resulting protein structures in different ways, from changes in polarity to folding alterations. Genetic and clinical associations led us to undertake a critical review of the classifications of late-onset GM1 gangliosidosis and Morquio B disease.


Assuntos
Gangliosidose GM1/genética , Mucopolissacaridose IV/genética , Sequência de Aminoácidos , Pré-Escolar , Feminino , Gangliosidose GM1/patologia , Genótipo , Humanos , Lactente , Modelos Moleculares , Dados de Sequência Molecular , Mucopolissacaridose IV/patologia , Mutação , Fenótipo , Homologia de Sequência de Aminoácidos , beta-Galactosidase/química , beta-Galactosidase/genética
10.
BMC Pediatr ; 12: 144, 2012 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-22950861

RESUMO

BACKGROUND: Despite progresses in neonatal care, the mortality and the incidence of neuro-motor disability after perinatal asphyxia have failed to show substantial improvements. In countries with a high level of perinatal care, the incidence of asphyxia responsible for moderate or severe encephalopathy is still 2-3 per 1000 term newborns. Recent trials have demonstrated that moderate hypothermia, started within 6 hours after birth and protracted for 72 hours, can significantly improve survival and reduce neurologic impairment in neonates with hypoxic-ischemic encephalopathy. It is not currently known whether neuroprotective drugs can further improve the beneficial effects of hypothermia. Topiramate has been proven to reduce brain injury in animal models of neonatal hypoxic ischemic encephalopathy. However, the association of mild hypothermia and topiramate treatment has never been studied in human newborns. The objective of this research project is to evaluate, through a multicenter randomized controlled trial, whether the efficacy of moderate hypothermia can be increased by concomitant topiramate treatment. METHODS/DESIGN: Term newborns (gestational age ≥ 36 weeks and birth weight ≥ 1800 g) with precocious metabolic, clinical and electroencephalographic (EEG) signs of hypoxic-ischemic encephalopathy will be randomized, according to their EEG pattern, to receive topiramate added to standard treatment with moderate hypothermia or standard treatment alone. Topiramate will be administered at 10 mg/kg once a day for the first 3 days of life. Topiramate concentrations will be measured on serial dried blood spots. 64 participants will be recruited in the study. To evaluate the safety of topiramate administration, cardiac and respiratory parameters will be continuously monitored. Blood samplings will be performed to check renal, liver and metabolic balance. To evaluate the efficacy of topiramate, the neurologic outcome of enrolled newborns will be evaluated by serial neurologic and neuroradiologic examinations. Visual function will be evaluated by means of behavioural standardized tests. DISCUSSION: This pilot study will explore the possible therapeutic role of topiramate in combination with moderate hypothermia. Any favourable results of this research might open new perspectives about the reduction of cerebral damage in asphyxiated newborns.


Assuntos
Frutose/análogos & derivados , Hipotermia Induzida , Hipóxia-Isquemia Encefálica/terapia , Fármacos Neuroprotetores/uso terapêutico , Terapia Combinada , Frutose/efeitos adversos , Frutose/uso terapêutico , Humanos , Recém-Nascido , Fármacos Neuroprotetores/efeitos adversos , Topiramato
11.
Pediatr Crit Care Med ; 12(6): e237-41, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21057354

RESUMO

OBJECTIVE: Terlipressin has been successfully used as rescue treatment in hypotensive adults and children with septic shock, but only exceptionally in neonates. The aim of this study is to describe original clinical scenarios in which terlipressin, in newborns and infants, resolved the catecholamine-refractory hypotension. DESIGN: Retrospective study. SETTING: Neonatal intensive care unit. PATIENTS: All newborns with hypotension unresponsive to volume replacement and catecholamines, and treated with terlipressin, from January 2008 to December 2009. In this study, also an infant (11 months old) born extremely preterm was included. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Four hypotensive patients received as rescue therapy terlipressin, which produced a dramatic increase in mean arterial pressure, diuresis, and reduction of lactate levels. In three newborns, hypotension, associated with pulmonary hypertension, was resolved with terlipressin. Two of them (one with systemic inflammatory response syndrome, the other with congenital diaphragmatic hernia) died in the following days for causes unrelated to hypotension; the third (on mild hypothermia for hypoxic-ischemic encephalopathy) recovered. We report furthermore an infant with septic shock and on treatment with ß-blockers in whom terlipressin normalized blood pressure. In two patients, cranial Doppler ultrasonography showed the recovery of diastolic cerebral flow in the anterior cerebral artery and the normalization of resistance index within 30 mins from the first dose of terlipressin. In two infants, hyponatremia was detected. CONCLUSION: Although the number of reported infants is little, terlipressin appears to be an effective rescue treatment in different scenarios of refractory neonatal hypotension. Further controlled studies are required to confirm its efficacy and safety.


Assuntos
Hipotensão/tratamento farmacológico , Lipressina/análogos & derivados , Vasoconstritores/uso terapêutico , Catecolaminas/uso terapêutico , Feminino , Humanos , Hipotensão/diagnóstico por imagem , Lactente , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Itália , Lipressina/administração & dosagem , Lipressina/uso terapêutico , Masculino , Auditoria Médica , Estudos Retrospectivos , Choque Séptico , Terlipressina , Ultrassonografia , Vasoconstritores/administração & dosagem
12.
J Neurol ; 266(1): 92-101, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30382391

RESUMO

BACKGROUND: Patients with Gaucher Disease (GD) exhibit three phenotypes, including type 1 (non-neuronopathic), type 2 (acute neuronopathic), and type 3 (subacute neuronopathic). AIM: Identifying which GBA changes represent benign polymorphisms and which may result in disease-causing mutations is essential for diagnosis and genotype/phenotype correlations but is often challenging. RESULTS: Here, we describe a patient with type 3 GD, presenting with drug-resistant epilepsy, who bears a set of GBA polymorphic variants including the novel c.363A > G (Gly82Gly) synonymous mutation. In silico predictions, mRNA and functional studies revealed that the new Gly82Gly mutation causes skipping of GBA exon 4, leading to a severe reduction of the wild type GBA mRNA. This is the first report of a synonymous change causing GD through loss of an exonic splicing enhancer sequence. The synonymous mutation is in trans with the Asn188Ser missense mutation, thus making the Asn188Ser responsible for the patient's phenotype and strengthening the association of Asn188Ser with the particular neurological phenotype of type 3 GD. CONCLUSION: We strengthen the association of Asn188Ser with the type 3 GD phenotype and progressive myoclonus epilepsy. Our data confirm that in silico predictions and mRNA analysis are mandatory in discriminating pathological mutations from the background of harmless polymorphisms, especially synonymous changes.


Assuntos
Epilepsia Resistente a Medicamentos/genética , Doença de Gaucher/genética , Glucosilceramidase/genética , Mutação , Epilepsias Mioclônicas Progressivas/genética , Adolescente , Encéfalo/fisiopatologia , Epilepsia Resistente a Medicamentos/enzimologia , Epilepsia Resistente a Medicamentos/fisiopatologia , Éxons , Feminino , Fibroblastos/enzimologia , Doença de Gaucher/enzimologia , Doença de Gaucher/fisiopatologia , Humanos , Epilepsias Mioclônicas Progressivas/enzimologia , Epilepsias Mioclônicas Progressivas/fisiopatologia , Fenótipo
13.
Biochim Biophys Acta ; 1770(6): 872-83, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17349748

RESUMO

This study demonstrates for the first time that sphingosine 1-phosphate (S1P) increases H2O2 production in NIH3T3 fibroblasts through NADPH oxidase activation, confirming the involvement of phosphoinositide-3-kinase and protein kinase C in the activation of this enzyme in non-phagocyte mammalian cells. The results demonstrate also that both platelet-derived growth factor (PDGF) and S1P-mediated NADPH oxidase activation and H2O2 production by Gi-protein coupled receptors (GPCRs) and c-Src kinase. Moreover, both PDGF and S1P activate c-Src kinase through GPCRs, indicating that this kinase can constitute a connection factor between PDGF and S1P signaling, confirming the cross-talk previously found between their receptors. Thus, Gi-protein-mediated NADPH oxidase activation with the consequent H2O2 increase constitutes an early event in the PDGF and S1P pathways. However, a different time course of H2O2 production in S1P-stimulated cells compared to that obtained in PDGF-stimulated cells has been observed, and this seems to be related to the different activation behavior of c-Src kinase induced after S1P or PDGF stimulation. Finally, these data demonstrate that S1P-induced H2O2 production is necessary to maximize c-Src kinase activation, confirming that this is a redox regulated kinase. After which, c-Src plays an important role both upstream and downstream from NADPH oxidase activation.


Assuntos
Lisofosfolipídeos/farmacologia , NADPH Oxidases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais/fisiologia , Esfingosina/análogos & derivados , Animais , Proteína Tirosina Quinase CSK , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Peróxido de Hidrogênio/metabolismo , Lisofosfolipídeos/metabolismo , Camundongos , Células NIH 3T3 , Oxirredução/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/efeitos dos fármacos , Esfingosina/metabolismo , Esfingosina/farmacologia , Quinases da Família src
14.
Free Radic Biol Med ; 44(8): 1624-36, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18294463

RESUMO

Recent data support the role of oxidative stress in the pathogenesis of Alzheimer disease (AD). In particular, glutathione (GSH) metabolism is altered and its levels are decreased in affected brain regions and peripheral cells from AD patients and in experimental models of AD. In the past decade, interest in the protective effects of various antioxidants aimed at increasing intracellular GSH content has been growing. Because much experimental evidence suggests a possible protective role of unsaturated fatty acids in age-related diseases, we designed the synthesis of new S-acylglutathione (acyl-SG) thioesters. S-Lauroylglutathione (lauroyl-SG) and S-palmitoleoylglutathione (palmitoleoyl-SG) were easily internalized into the cells and they significantly reduced Abeta42-induced oxidative stress in human neurotypic SH-SY5Y cells. In particular, acyl-SG thioesters can prevent the impairment of intracellular ROS scavengers, intracellular ROS accumulation, lipid peroxidation, and apoptotic pathway activation. Palmitoleoyl-SG seemed more effective in cellular protection against Abeta-induced oxidative damage than lauroyl-SG, suggesting a valuable role for the monounsaturated fatty acid. In this study, we demonstrate that acyl-SG derivatives completely avoid the sharp lipoperoxidation in primary fibroblasts from familial AD patients occurring after exposure to Abeta42 aggregates. Hence, we put forward these derivatives as new antioxidant compounds which could be excellent candidates for therapeutic treatment of AD and other oxidative stress-related diseases.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Antioxidantes/farmacologia , Fibroblastos/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Doença de Alzheimer/metabolismo , Antioxidantes/síntese química , Apoptose/efeitos dos fármacos , Glutationa/análogos & derivados , Glutationa/síntese química , Glutationa/metabolismo , Glutationa/farmacologia , Humanos , Lauratos/síntese química , Lauratos/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Neuroblastoma , Palmitatos/síntese química , Palmitatos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Células Tumorais Cultivadas
15.
Inflamm Bowel Dis ; 14(6): 819-25, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18266233

RESUMO

BACKGROUND: The etiology of Crohn's disease (CD) remains unknown, and the defective function of neutrophils appears to be associated with this pathology. Neutrophils undergo spontaneous apoptosis which, if not tightly regulated, can induce the development of chronic inflammatory disease. The Bcl-2 protein family is also involved in the regulation of neutrophil apoptosis. METHODS: This study investigated the apoptosis and expression of some regulatory factors in CD patient and control polymorphonuclear neutrophils (PMN) in suspension and in adhesion on fibronectin, an extracellular matrix protein. These 2 conditions mimic circulating neutrophils before they are recruited at the intestinal levels, and their adhesion to tissue. RESULTS: Apoptosis in CD patient PMN was delayed in suspension and accelerated in adhesion, which is the opposite of what happens in controls. Higher levels of Bax, Bcl-2, and Mcl-1 proteins were registered in freshly isolated CD patient PMN, in contrast to controls, in which Bcl-2 protein was undetectable. Among the studied pro- and antiapoptotic factors, Bax levels seem to be mainly related to the difference in apoptosis between PMN of CD patients and controls. CONCLUSIONS: For the first time it has been demonstrated by direct experimental evidence that apoptosis in CD patient PMN is regulated differently from that of control PMN. Abnormal expression of regulating apoptosis proteins is shown in CD patient PMN. These data suggest that the defective functionality of neutrophils can be the early event responsible for the altered mucosal immune response in CD, and that neutrophil apoptosis may offer a new target for specific drugs and therapy tools.


Assuntos
Apoptose/fisiologia , Doença de Crohn/patologia , Neutrófilos/química , Neutrófilos/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/sangue , Proteína X Associada a bcl-2/sangue , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteína de Sequência 1 de Leucemia de Células Mieloides
16.
Neurosci Lett ; 668: 103-107, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29339173

RESUMO

Hypoxic-ischemic encephalopathy (HIE) is a major cause of perinatal mortality and subsequent severe neurological sequelae. Mild hypothermia is a standard therapy for HIE, but is used only in selected Reference Centers and in neonates >1800 g. Since neuronal death following HIE occurs by a cascade of events triggered by activation of glutamate receptors, we used in vitro and in vivo models of HIE to examine whether the AMPA/kainate receptor antagonist topiramate and the NMDA receptor antagonist memantine could exert neuroprotective effects, alone or in combination with hypothermia. For the in vitro experiments, rat organotypic hippocampal slices were exposed to a 30 min duration of oxygen-glucose deprivation (OGD): treatment with topiramate (1 µM) and memantine (10-30 µM) or hypothermia (35 °C or 32 °C) significantly attenuated CA1 damage after 24 h. The combination of hypothermia with topiramate and memantine enhanced their protective effect. For the in vivo experiments, we used 7 day-old rat pups subjected to permanent left common carotid artery occlusion followed by 120 min of hypoxia. Administration of topiramate or memantine (i.p., 20 mg/kg) immediately and 2 h after hypoxia or exposure to hypothermia (32 °C for 4 h beginning 1 h after hypoxia) significantly reduced the extent of the resulting infarct. The combination of topiramate or memantine with hypothermia elicited a reduction of the infarct that was greater than that produced by drugs or hypothermia alone. Notably, memantine displayed a higher degree of neuroprotection as compared to topiramate both in vitro and in vivo and, when used alone at 20 mg/kg in vivo, produced a greater reduction in brain damage than observed using topiramate in combination with hypothermia. These results suggest that memantine may be more advantageous than topiramate as a therapeutic agent in neonates with HIE treated with hypothermia.


Assuntos
Frutose/análogos & derivados , Hipotermia Induzida/métodos , Hipóxia-Isquemia Encefálica/terapia , Memantina/farmacologia , Fármacos Neuroprotetores/farmacologia , Animais , Animais Recém-Nascidos , Terapia Combinada , Modelos Animais de Doenças , Frutose/administração & dosagem , Frutose/farmacologia , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Memantina/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Ratos , Ratos Wistar , Topiramato
17.
J Matern Fetal Neonatal Med ; 31(8): 973-980, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28274169

RESUMO

PURPOSE: To investigate the feasibility of a study based on treatment with topiramate (TPM) added to moderate hypothermia in newborns with hypoxic ischemic encephalopathy (HIE). MATERIALS AND METHODS: Multicenter randomized controlled trial. Term newborns with precocious metabolic, clinical and electroencephalographic (EEG) signs of HIE were selected according to their amplified integrated EEG pattern and randomized to receive either TPM (10 mg/kg once a day for the first three days of life) plus moderate hypothermia or hypothermia alone. Safety was assessed by monitoring cardiorespiratory parameters and blood samples collected to check renal, liver, metabolic balance and TPM pharmacokinetics. Efficacy was evaluated by the combined frequency of mortality and severe neurological disability as primary outcome. Incidence of magnetic resonance injury, epilepsy, blindness, hearing loss, neurodevelopment at 18-24 months of life was assessed as secondary outcomes. RESULTS: Forty-four asphyxiated newborns were enrolled in the study. Twenty one newborns (10 with moderate and 11 with severe HIE) were allocated to hypothermia plus TPM and 23 (12 moderate and 11 severe HIE) to hypothermia. No statistically or clinically significant differences were observed for safety, primary or secondary outcomes. However, a reduction in the prevalence of epilepsy was observed in newborns co-treated with TPM. CONCLUSIONS: Results of this pilot trial suggest that administration of TPM in newborns with HIE is safe but does not reduce the combined frequency of mortality and severe neurological disability. The role of TPM co-treatment in preventing subsequent epilepsy deserves further studies.


Assuntos
Frutose/análogos & derivados , Hipotermia Induzida , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Estudos de Viabilidade , Feminino , Frutose/farmacocinética , Frutose/uso terapêutico , Humanos , Hipóxia-Isquemia Encefálica/diagnóstico por imagem , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Fármacos Neuroprotetores/farmacocinética , Topiramato , Resultado do Tratamento
18.
Biochim Biophys Acta ; 1745(2): 166-75, 2005 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-16129124

RESUMO

This study identifies some early events contributing to the redox regulation of platelet-derived growth factor receptor (PDGFr) activation and its signalling in NIH3T3 fibroblasts. We demonstrate for the first time that the redox regulation of PDGFr tyrosine autophosphorylation and its signalling are related to NADPH oxidase activity through protein kinase C (PKC) and phosphoinositide-3-kinase (PI3K) activation and H2O2 production. This event is also essential for complete PDGF-induced activation of c-Src kinase by Tyr416 phosphorylation, and the involvement of c-Src kinase on H2O2-induced PDGFr tyrosine phosphorylation is demonstrated, suggesting a role of this kinase on the redox regulation of PDGFr activation. Finally, it has been determined that not only PI3K activity, but also PKC activity, are related to NADPH oxidase activation due to PDGF stimulation in NIH3T3 cells, as it occurs in non-phagocyte cells. Therefore, we suggest a redox circuit whereby, upon PDGF stimulation, PKC, PI3K and NADPH oxidase activity contribute to complete c-Src kinase activation, thus promoting maximal phosphorylation and activation of PDGFr tyrosine phosphorylation.


Assuntos
NADPH Oxidases/fisiologia , Proteínas Tirosina Quinases/fisiologia , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Animais , Proteína Tirosina Quinase CSK , Citoplasma/metabolismo , Peróxido de Hidrogênio/metabolismo , Camundongos , Células NIH 3T3 , Oxirredução , Fosfatidilinositol 3-Quinases/fisiologia , Fosforilação , Fator de Crescimento Derivado de Plaquetas/fisiologia , Proteína Quinase C/fisiologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Receptores do Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Transdução de Sinais/fisiologia , Superóxidos/metabolismo , Quinases da Família src
19.
Exp Biol Med (Maywood) ; 231(2): 186-95, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16446495

RESUMO

The aim of this in vitro study was to evaluate the intracellular redox state and respiratory burst (RB) in neutrophils of patients with Crohn's disease (CD). The intracellular redox state and RB in neutrophils was assessed by the superoxide anion (O2*-) production induced in these cells after stimulation by various factors related to the molecular mechanisms that, if altered, may be responsible for an abnormal immune response. This can, in part, cause the onset of inflammation and tissue damage seen in CD. This study demonstrated a decreased glutathione/glutathione disulfide (GSH/GSSG) ratio index of an increased oxidative state in CD patient neutrophils. Moreover, our findings showed a decrease in tumor necrosis factor (TNF-alpha)- or phorbol 12-myristate 13-acetate (PMA)-induced O2*- production in CD patient neutrophils adherent to fibronectin as compared with controls. A decreased adhesion was also demonstrated. For this reason, the involvement of altered mechanisms of protein kinase C (PKC) and beta-integrin activation in CD patient neutrophils is suggested. These data also showed that the harmful effects of TNF-alpha cannot be caused by excessive reactive oxygen species (ROS) production induced by neutrophils. Decreased cell viability after a prolonged time of adhesion (20 hrs) was also measured in CD patient neutrophils. The findings of this study demonstrate, for the first time, that granulocyte-macrophage colony-stimulating factor (GM-CSF), a compound recently used in CD therapy, is able to activate the RB for a prolonged time both in control and CD patient neutrophils. Increased viability of CD patient neutrophils caused by GM-CSF stimulation was also observed. In conclusion, our results indicate that decreased O2*- production and adhesion, caused, in part, by an anomalous response to TNF-alpha, together with low GSH level and low cell viability, may be responsible for the defective neutrophil function found in CD patients. This can contribute to the chronic inflammation and relapses that characterize this pathology. A possible role of GM-CSF in inducing O2*- production and in restoring the defensive role of neutrophils in CD patients is suggested.


Assuntos
Doença de Crohn/metabolismo , Neutrófilos/metabolismo , Superóxidos/metabolismo , Adulto , Adesão Celular , Sobrevivência Celular , Células Cultivadas , Feminino , Fibronectinas/metabolismo , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/citologia , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Explosão Respiratória/fisiologia , Acetato de Tetradecanoilforbol/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
20.
J Matern Fetal Neonatal Med ; 19(4): 221-4, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16854695

RESUMO

OBJECTIVE: To identify compliance-influencing factors and to suggest strategies for overcoming barriers in a preventive medicine program. METHODS: A survey was conducted to evaluate compliance in children receiving palivizumab prophylaxis for respiratory syncytial virus (RSV) infections. Demographics, neonatal variables, and parental attitudes capable of influencing the outcome of prophylaxis were studied in 216 children over a four-year period. RESULTS: The overall compliance rate with all recommended doses of palivizumab was 87%. Among the neonatal characteristics, low birth weight and a younger age at the beginning of the program were significantly associated with good compliance (p < 0.05). The strongest factor influencing poor compliance was being foreign-born or a non-native speaker (p < 0.01). CONCLUSIONS: Compliance to RSV infection prophylaxis is reduced in infants born to foreign-born or non-native speakers. In order to enhance compliance, parents should be provided with adequate information in their own language explaining the advantages of the palivizumab prophylaxis program for RSV infections.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Antivirais/administração & dosagem , Cooperação do Paciente/estatística & dados numéricos , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Anticorpos Monoclonais Humanizados , Peso ao Nascer , Barreiras de Comunicação , Esquema de Medicação , Humanos , Lactente , Palivizumab , Cooperação do Paciente/psicologia
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