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1.
Mult Scler Relat Disord ; 79: 104942, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37633034

RESUMO

BACKGROUND: Pediatric forms of multiple sclerosis are more active than those in adults. Yet, the effectiveness of different therapeutic approaches is not well studied in this population. Our objective was to compare the effectiveness of the early use of high efficacy therapies (HETs) with the effectiveness of moderate efficacy therapies (METs) in children with MS. METHODS: This observational study included patients diagnosed with pediatric MS, at 4 hospital centers in France, during a 10-year period. METs included: interferon ß-1a, glatiramer acetate, dimethyl fumarate, teriflunomide; HETs included: fingolimod, natalizumab, ocrelizumab, alemtuzumab. The primary endpoint was the occurrence of a new relapse, the secondary endpoint was EDSS worsening. RESULTS: Sixty-four patients were included in the analysis (80% women; mean age 15.5 years, 81% treated with MET) with a median follow-up of 22.5 months. At baseline, 52 patients were on MET (interferon ß-1a, glatiramer acetate, dimethyl fumarate, teriflunomide) and 12 patients were on HET (natalizumab, ocrelizumab). The cumulative probability of being relapse-free at 6.5 years was 23.3% on MET, vs 90.9% on HET (p = 0.013). The cumulative probability of no EDSS worsening did not differ between the 2 groups. CONCLUSION: Patients starting with METs had much higher clinical disease activity than those starting early with HETs. Rapid initiation of more aggressive treatment may allow better disease control; however, the data on EDSS worsening are not conclusive.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Adolescente , Criança , Feminino , Humanos , Masculino , Fumarato de Dimetilo/uso terapêutico , Cloridrato de Fingolimode/uso terapêutico , Acetato de Glatiramer/uso terapêutico , Imunossupressores/uso terapêutico , Interferon beta-1a/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Natalizumab/uso terapêutico , Recidiva
2.
Cancers (Basel) ; 14(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36428602

RESUMO

Background: Describe the characteristics, patterns of care, and predictive geriatric factors of elderly patients with IDHm high-grade glioma (HGG) included in the French POLA network. Material and Methods: The characteristics of elderly (≥70 years) patients IDHm HGG were compared to those of younger patients IDHm HGG (<70 years) and of elderly patients IDHwt HGG. Geriatric features were collected. Results: Out of 1433 HGG patients included, 119 (8.3%) were ≥70 years. Among them, 39 presented with IDHm HGG. The main characteristics of elderly IDHm HGG were different from those of elderly IDHwt HGG but similar to those of younger IDHm HGG. In contrast, their therapeutic management was different from those of younger IDHm HGG with less frequent gross total resection and radiotherapy. The median progression-free survival (PFS) and overall survival (OS) were longer for elderly patients IDHm HGG (29.3 months and 62.1 months) than elderly patients IDHwt HGG (8.3 months and 13.3 months) but shorter than those of younger patients IDHm HGG (69.1 months and not reached). Geriatric factors associated with PFS and OS were mobility, neuropsychological disorders, body mass index, and autonomy. Geriatric factors associated with PFS and OS were mobility, neuropsychological disorders, and body mass index, and autonomy. Conclusion: the outcome of IDHm HGG in elderly patients is better than that of IDHwt HGG. Geriatric assessment may be particularly important to optimally manage these patients.

3.
J Neurol ; 269(6): 3295-3300, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34982200

RESUMO

BACKGROUND: Exit strategy after natalizumab cessation in multiple sclerosis (MS) is a crucial point because the risk of disease reactivation is high during this period. The objective of this observational study was to compare ocrelizumab to fingolimod after natalizumab cessation in patients with relapsing-remitting multiple sclerosis (RRMS). METHODS: All RRMS patients starting fingolimod or ocrelizumab within 6 weeks after natalizumab cessation were included. The primary endpoint was the annualized relapse rate (ARR) at 1 year. RESULTS: We included 54 patients receiving fingolimod and 48 patients receiving ocrelizumab after natalizumab cessation. In multivariate analysis, ARR at 1 year was significantly lower in the ocrelizumab group than in the fingolimod group (0.12 ± 0.39 versus 0.41 ± 0.71, p = 0.026), i.e. a 70.7% lower relapse rate. The cumulative probability of relapses at 1 year was 31.5% (17/54 patients) with fingolimod and 10.4% (5/48 patients) with ocrelizumab, corresponding to a hazard ratio of 3.4 (95% confidence interval: 1.1-11, p = 0.04). CONCLUSIONS: Our results suggest ocrelizumab is potentially a better exit strategy than fingolimod after natalizumab cessation.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Anticorpos Monoclonais Humanizados , Cloridrato de Fingolimode/efeitos adversos , Humanos , Fatores Imunológicos/efeitos adversos , Imunossupressores/efeitos adversos , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Natalizumab/efeitos adversos , Recidiva
4.
J Neurol ; 268(8): 2890-2894, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33609156

RESUMO

BACKGROUND: Interleukin 6 (IL-6) is a pleomorphic cytokine that can be found in the cerebrospinal fluid (CSF) in a wide spectrum of inflammatory pathologies of the central nervous system (CNS). OBJECTIVE: Our aim was to characterize the diagnostic significance of CSF IL-6 among various CNS inflammatory diseases with pseudotumoral lesions (CNSID) and primary CNS lymphoma (PCNSL). METHODS: We retrospectively analyzed the CSF IL-6 concentrations in 43 consecutive patients with suspected PCNSL. A total of 28 patients were positively diagnosed with PCNSL and 15 with CNSID. We verified the results with CSF IL-10, an established biomarker for PCNSL. RESULTS: In the PCNSL group, the median CSF IL-6 concentration was 8 pg/ml, interquartile range (IQR) 5-18.5. For the patients with CNSID, the median concentration was 70 pg/ml, IQR 5-1368. A group comparison showed significantly higher CSF IL-6 levels in patients with CNSID than in those with PCNSL (p = 0.032). Moreover, IL-6 was correlated with CSF cell count in the CNSID group (r = 0.56, p = 0.028), but not in the PCNSL group (r = 0.3, p = 0.13). We found significantly higher CSF IL-10 levels in patients with PCNSL than in patients with CNS inflammatory lesions (p < 0.001). DISCUSSION AND CONCLUSIONS: Our study suggests that CSF IL-6 levels could represent, in addition to CSF IL-10, a useful biomarker in the differential diagnosis of CNSID and suspected PCNSL.


Assuntos
Neoplasias do Sistema Nervoso Central , Granuloma de Células Plasmáticas/diagnóstico , Interleucina-6/líquido cefalorraquidiano , Linfoma , Biomarcadores Tumorais , Neoplasias do Sistema Nervoso Central/diagnóstico , Diagnóstico Diferencial , Humanos , Linfoma/diagnóstico , Estudos Retrospectivos
5.
JAMA Neurol ; 74(11): 1368-1373, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28973119

RESUMO

Importance: Visual impairment in primary central nervous system lymphoma (PCNSL) is caused mostly by intraocular lymphomatous involvement (vitritis and retinal infiltration), whereas optic nerve infiltration (ONI) is a rare condition. Objective: To describe the clinical presentation of ONI, its imaging characteristics, and outcome. Design, Setting and Participants: A total of 752 patients diagnosed with PCNSL were retrospectively identified from the databases of 3 French hospitals from January 1, 1998, through December 31, 2014. Of these, 7 patients had documented ONI. Exclusion criteria were intraocular involvement, orbital lymphoma, or other systemic lymphoma. Clinical presentation, neuroimaging, biological features, treatment, and outcomes were assessed. Main Outcomes and Measures: Treatment response was evaluated clinically and radiologically on follow-up magnetic resonance imaging (MRI) according to the International PCNSL Collaborative Group response criteria. Results: The 7 patients included 5 women and 2 men. Median age at diagnosis was 65 years (range, 49-78 years). Two patients had initial ONI at diagnosis, and 5 had ONI at relapse. Clinical presentation was marked by rapidly progressive and severe visual impairment for all patients. The MRI findings showed optic nerve enlargement in 3 patients and contrast enhancement of the optic nerve in all patients. Additional CNS lesions were seen in 4 patients. Examination of cerebrospinal fluid samples detected lymphomatous meningitis in 2 patients. Clinical outcome was poor and marked by partial recovery for 2 patients and persistent severe low visual acuity or blindness for 5 patients. Median progression-free survival after optic nerve infiltration was 11 months (95% CI, 9-13 months), and median overall survival was 18 months (95% CI, 9-27 months). Conclusions and Relevance: Optic nerve infiltration is an atypical and challenging presentation of PCNSL. Its visual and systemic prognosis is particularly poor compared with vitreoretinal lymphomas even in response to chemotherapy. Although intraocular involvement is frequent in PCNSL and clinically marked by slowly progressive visual deterioration, lymphomatous ONI is rare and characterized by rapidly progressive severe visual impairment.


Assuntos
Neoplasias do Sistema Nervoso Central/complicações , Linfoma/complicações , Doenças do Nervo Óptico/diagnóstico por imagem , Doenças do Nervo Óptico/patologia , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doenças do Nervo Óptico/etiologia , Estudos Retrospectivos
6.
J Neurooncol ; 133(2): 315-320, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28432587

RESUMO

Primary CNS lymphoma (PCNSL) is chemosensitive to high-dose methotrexate-based chemotherapy. However, responses in the elderly are short-lasting and outcome is poor. Given that radiotherapy and intensive chemotherapy expose elderly to severe toxicities, alternative consolidation approaches need to be evaluated. In this multicenter study, we retrospectively analyzed consecutive patients with newly-diagnosed PCNSL, aged >60, treated with a (R)-MPV-AAA regimen. The regimen consisted of three 28-day cycles of methotrexate (3.5 g/m2 D1, D15), procarbazine, vincristine, followed by three 28-day cycles of cytarabine consolidation (3 g/m2 D1-2). Addition of rituximab (375 mg/m2 D1) was optional. The results were compared with the historical MPV-A regimen. Ninety patients received the (R)-MPV-AAA regimen with (n = 39) or without (n = 51) rituximab. Median age was 68 and median KPS 60. 55% of patients achieved a complete response, 8% a partial response and 37% progressed. The median PFS was 10 months, the median OS 28.1 months. Toxicity was mainly hematological, with 54 and 51% of grade III-IV neutropenia and thrombopenia. The response rate was higher in patients receiving rituximab (77 vs. 53%; p = 0.03), whereas no difference was observed in terms of PFS or OS. When comparing the results to the historical MPV-A, there was no difference in terms of response rate, PFS or OS, but a higher rate of hematotoxicity. This study suggests that extending cytarabine consolidation after methotrexate-based chemotherapy does not improve the MPV-A efficacy but increases toxicity in the elderly. The addition of rituximab may improve the response rate, but its impact on final outcome remains unclear.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Linfoma/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Citarabina/uso terapêutico , Feminino , Seguimentos , Humanos , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-Idade , Procarbazina/uso terapêutico , Estudos Retrospectivos , Rituximab/uso terapêutico , Resultado do Tratamento
7.
Neurology ; 85(15): 1325-31, 2015 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26385879

RESUMO

OBJECTIVES: We aimed to study the potential clinical relevance of 9p allelic loss, with or without copy number variation, in 1p/19q codeleted anaplastic oligodendroglial tumors (AOTs). METHODS: This study enrolled 216 patients with 1p/19q codeleted AOT. The prognostic value of 9p allelic loss was investigated using a French nation-wide prospective registry, POLA (prise en charge des tumeurs oligodendrogliales anaplasiques) and high-density single nucleotide polymorphism arrays. We validated our results using the Repository of Molecular Brain Neoplasia Data (REMBRANDT) dataset. RESULTS: The minimal common region of allelic loss in chromosome arm 9p was 9p21.3. Allelic loss of 9p21.3, detected in 41.7% of tumors, was associated with shorter progression-free and overall survival rates in univariate (p = 0.008 and p < 0.001, respectively) and multivariate analyses (p = 0.009 and p = 0.009, respectively). This finding was validated in the REMBRANDT dataset in univariate and multivariate analysis (p = 0.01 and p = 0.01, respectively). CONCLUSION: Our study highlights a novel potential prognostic biomarker in 1p/19q codeleted AOT. Further prospective studies are warranted to investigate our finding.


Assuntos
Neoplasias Encefálicas/genética , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 9/genética , Variações do Número de Cópias de DNA/genética , Glioma/diagnóstico , Glioma/epidemiologia , Perda de Heterozigosidade/genética , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patologia , Deleção Cromossômica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos
9.
J Clin Epidemiol ; 66(10): 1151-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23856188

RESUMO

OBJECTIVES: The aim of this survey was to quantify refusal rates and identify factors of refusal pertaining to studies and recruiting pediatricians in the research recruitment process. STUDY DESIGN AND SETTING: We performed a cross-sectional survey on all clinical studies conducted in six pediatric Clinical Investigation Centers in France over an 18-month period. Data were retrieved using a data collection form for the characteristics of each of the studies included in the survey and a questionnaire addressed to recruiting pediatricians. Multilevel models were used for the statistical analysis. RESULTS: Overall, 145 pediatricians approached the families of 999 children and adolescents for participation in 44 studies. In the 36 of the 44 studies that enrolled subjects, median refusal rate was 12.5% (Q1-Q3, 0-28%). Lower refusal rates were associated with therapeutic drug use as the focus of the study [odds ratio (OR), 0.51; 95% CI: 0.25, 1.05], additional hospital stays required for the study (OR, 0.53; 95% CI: 0.28, 0.99), longer duration of the inclusion visit (OR, 0.93/10 min; 95% CI: 0.87, 1), and recruitment by a pediatrician with university teaching responsibilities (OR, 0.26; 95% CI: 0.10, 0.68). Refusal rate was higher when the recruiting pediatrician perceived the study as generating heavy practical burden for the subject and/or its family (OR, 1.3; 95% CI: 1.17, 1.45). CONCLUSION: Refusal to participate in clinical research was low and was influenced by factors associated to the objectives and conduct of the studies and factors related to the characteristics and perceptions of the recruiting pediatricians.


Assuntos
Atitude do Pessoal de Saúde , Pesquisa Biomédica/organização & administração , Seleção de Pacientes , Pediatria , Médicos/psicologia , Recusa de Participação/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Coleta de Dados , Feminino , França , Humanos , Lactente , Recém-Nascido , Masculino , Análise Multinível , Projetos de Pesquisa , Inquéritos e Questionários
10.
Epilepsy Res ; 102(3): 206-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22959716

RESUMO

OBJECTIVE: To describe the aetiology of a particular form of late-onset temporal lobe epilepsy (TLE) - the Epileptic Amnesic Syndrome (EAS) - that can be responsible for cognitive decline. The syndrome is considered as a reversible cause of memory disturbances, but some patients remain unrelieved despite anticonvulsants. DESIGN: 4 case-reports and a brief discussion. SETTING: University Hospital. PATIENTS: 4 patients fulfilling the diagnosis criteria of EAS but for whom a progressive causative disease was suspected because they still complained from their memory after antiepileptic treatment. RESULTS: All patients had characteristics suggesting Alzheimer's disease. Memory disturbances were systematically combined with other non-episodic cognitive impairments. CSF biomarkers were compatible with AD pathological changes. Moreover, brain MRI showed temporal lobe atrophy and neurological examination showed subtle abnormalities in all 4. CONCLUSION: AD should be kept in mind even though the patients meet the clinical criteria of EAS. This short series highlights the clinical characteristics that should be considered as "red-flags" in EAS patients because their presence makes the diagnosis of EAS improbable. In such a situation, particularly when cognitive improvement is lacking under treatment, a lumbar puncture is warranted.


Assuntos
Doença de Alzheimer/complicações , Amnésia/etiologia , Epilepsia/etiologia , Idoso , Doença de Alzheimer/diagnóstico , Amnésia/complicações , Amnésia/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Anticonvulsivantes/uso terapêutico , Progressão da Doença , Epilepsia/complicações , Epilepsia/tratamento farmacológico , Feminino , Seguimentos , Humanos , Masculino , Entrevista Psiquiátrica Padronizada , Fragmentos de Peptídeos/metabolismo , Proteínas tau/metabolismo
11.
Contemp Clin Trials ; 32(1): 16-24, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20951234

RESUMO

CONTEXT: Good Clinical Practice regulates monitoring activities in clinical research. Due to question and design diversity, and limited resources, on-site monitoring is often less intensive in the academic context, and variable. Standardization is needed, and relies on definition and validation of tools accounting for risk. OBJECTIVE: To define, and validate tools, to implement a risk-based monitoring strategy for academic clinical research. METHODS: Working groups of experienced professionals searched the literature, and built a consensus risk-assessment scale (RAS), and a risk-adapted monitoring plan (RAMP). We allocated 200 protocols to 49 assessors. We assessed the RAS relevance vs. a visual analogue scale (VAS), and its reproducibility through Kraemer's kappa, and intraclass correlation coefficient (ICC) from a random proportional odds model. We identified sources of disagreement through a logistic regression. We described assessors' difficulties during assessment. We applied the RAMP to 10 protocols per risk level, and rated its feasibility (0 = easy to 4 = impossible). RESULTS: RAS and RAMP were defined in 4 levels. RAS relevance was good: RAS-risk levels were evenly distributed on VAS-risk (0.6, 2.6, 5.6, and 7.9). Reproducibility was moderate to good: kappa=0.48, ICC=0.70. Major disagreements (36%) arose from decision-makers, rather than hands-on managers. Most difficulties occurred in ill-written protocols (17%). RAMP was easily feasible for most protocols (mean score: 0.2 to 0.9). We proposed a standard synopsis for evaluation purpose. CONCLUSION: We defined, and validated risk-based tools. This risk-adapted strategy will be compared to an intensive one in a randomized trial, Optimon, to define a standard of practice for academic clinical research.


Assuntos
Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Medição de Risco/métodos , Protocolos Clínicos/normas , Humanos , Variações Dependentes do Observador , Guias de Prática Clínica como Assunto/normas , Reprodutibilidade dos Testes , Estatísticas não Paramétricas
12.
Am J Respir Crit Care Med ; 177(8): 906-11, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18079495

RESUMO

RATIONALE: Late-onset central hypoventilation syndrome (LO-CHS) is a rare disorder that may manifest as early as infancy or as late as during adulthood. The potential overlap of LO-CHS with congenital CHS is under debate, even though both disorders can result from heterozygous PHOX2B gene mutations. OBJECTIVES: To characterize the PHOX2B status in a series of 25 patients with LO-CHS referred from 3 months of age to adulthood. Whenever a PHOX2B mutation was identified, we ascertained its germline or somatic origin in both patients with LO-CHS and in 15 parents of probands with congenital CHS found to harbor a PHOX2B mutation. METHODS: The PHOX2B gene was analyzed by direct DNA sequencing and origin of the mutation evaluated by fluorescent PCR. MEASUREMENTS AND MAIN RESULTS: We have identified a heterozygous PHOX2B gene mutation in 17 of 25 patients with LO-CHS. The far most frequent mutation results in a germline +5 alanine expansion in the series of 20 alanines (15 cases) that show incomplete penetrance and variable expressivity, possibly resulting from combined environmental and genetic factors. PHOX2B frameshift and missense mutations have also been identified in patients with LO-CHS. Importantly, one parent found to harbor a somatic mosaic for a +8 alanine expansion developed alveolar hypoventilation in his 40s. CONCLUSIONS: These data indicate that PHOX2B gene mutations should be systematically examined in any adult with unexplained central hypoventilation and raise the question of follow-up for apparently healthy parents found to harbor a somatic mosaic for the PHOX2B mutation identified in their child.


Assuntos
Predisposição Genética para Doença/genética , Proteínas de Homeodomínio/genética , Apneia do Sono Tipo Central/genética , Fatores de Transcrição/genética , Adolescente , Adulto , Criança , Pré-Escolar , Expansão das Repetições de DNA , Feminino , Mutação da Fase de Leitura , Mutação em Linhagem Germinativa , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Mosaicismo , Mutação de Sentido Incorreto
14.
Arch Pediatr Adolesc Med ; 161(5): 446-50, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17485619

RESUMO

OBJECTIVE: To identify subjective factors that lead investigators not to invite eligible individuals to participate in pediatric studies. DESIGN: Qualitative study with semistructured interviews. SETTING: Four pediatric teaching hospitals in Paris. PARTICIPANTS: Pediatric investigators (n=24). MAIN OUTCOME MEASURE: Report by investigator that eligible patients were not invited by him or her to participate in a clinical research study. RESULTS: Sixty-three percent of investigators (15 of 24) reported not inviting eligible patients. The noninvitation patterns were global (ie, investigators did not invite anyone) (37.5% [9/24]) or targeted specific patient subgroups (37.5% [9/24]). Noninvitation was often described as driven by ethical concerns related to the study design or patients or by anticipated patient refusal (58.3% [14/24]). None of the investigators kept records of noninvitation rates or refusal rates. Investigators estimated refusal rates of 1% to 10%, and none remembered a study that had failed because of potential subjects' refusals (including healthy participants). CONCLUSIONS: Noninvitation to participate in studies is not an absence of action but rather is an organized practice that reflects investigators' perceptions. Consequences are practical (eg, recruitment bias and study failure) and ethical (eg, unequal access to trials and failure to respect the autonomy of eligible patients). Our data suggest an urgent need for quantitative studies aimed at documenting and understanding noninvitation of eligible patients to participate in research studies in pediatrics and in other medical specialties.


Assuntos
Atitude do Pessoal de Saúde , Ensaios Clínicos como Assunto , Seleção de Pacientes , Pediatria , Criança , Ensaios Clínicos como Assunto/ética , Tomada de Decisões , Avaliação de Medicamentos/ética , Feminino , Hospitais Pediátricos , Hospitais de Ensino , Humanos , Entrevistas como Assunto , Masculino , Paris , Seleção de Pacientes/ética , Pediatria/ética , Percepção , Pesquisa Qualitativa , Recusa de Participação , Viés de Seleção
15.
ILAR J ; 47(1): 15-21, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16391427

RESUMO

Recent studies described the in vivo respiratory phenotype of mutant newborn mice with targeted deletions of genes involved in respiratory control development. Whole-body flow barometric plethysmography is the noninvasive method of choice for studying unrestrained newborn mice. The main characteristics of the early postnatal development of respiratory control in mice are reviewed, including available data on breathing patterns and on hypoxic and hypercapnic ventilatory responses. Mice are very immature at birth, and their instable breathing is similar to that of preterm infants. Breathing pattern abnormalities with prolonged apneas occur in newborn mice that lack genes involved in the development of rhythmogenesis. Some mutant newborn mice have blunted hypoxic and hypercapnic ventilatory responses whereas others exhibit impairments in responses to hypoxia or hypercapnia. Furthermore, combined studies in mutant newborn mice and in humans have helped to provide pathogenic information on genetically determined developmental disorders of respiratory control in humans.


Assuntos
Camundongos , Modelos Animais , Fenótipo , Pletismografia Total/métodos , Transtornos Respiratórios/genética , Transtornos Respiratórios/fisiopatologia , Animais , Hipercapnia/fisiopatologia , Hipersensibilidade/fisiopatologia , Hipóxia/fisiopatologia , Camundongos Transgênicos , Estimulação Química
16.
Respir Physiol Neurobiol ; 149(1-3): 3-15, 2005 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-15941676

RESUMO

The mechanisms underlying respiratory system immaturity in newborns have been investigated, both in vivo and in vitro, in humans and in animals. Immaturity affects breathing rhythmicity and its modulation by suprapontine influences and by afferents from central and peripheral chemoreceptors. Recent research has moved from bedside tools to sophisticated technologies, bringing new insights into the plasticity and genetics of respiratory control development. Genetic research has benefited from investigations of newborn mice having targeted deletions of genes involved in respiratory control. Genetic variability may govern the normal programming of development and the processes underlying adaptation to homeostasis disturbances induced by prenatal and postnatal insults. Studies of plasticity have emphasized the role of neurotrophic factors. Improvements in our understanding of the mechanistic effects of these factors should lead to new neuroprotective strategies for infants at risk for early respiratory control disturbances, such as apnoeas of prematurity, sudden infant death syndrome and congenital central hypoventilation syndrome.


Assuntos
Centro Respiratório/crescimento & desenvolvimento , Fenômenos Fisiológicos Respiratórios , Sistema Respiratório/crescimento & desenvolvimento , Animais , Humanos
17.
Pediatr Res ; 58(1): 1-6, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15901893

RESUMO

Hirschsprung disease, neuroblastomas, and congenital central hypoventilation syndrome can occur in combination, and familial cases have been reported in all three conditions. This suggests variable expression of a single genetic abnormality as the common cause to these neural crest disorders. Because the PHOX2B gene is pivotal in the development of most relays of the autonomic nervous system, including all autonomic neural crest derivatives, it was considered a candidate gene for the above conditions. Recent studies have shown that 1) PHOX2B is the main disease-causing gene for congenital central hypoventilation syndrome, an autosomal dominant disorder with incomplete penetrance; 2) PHOX2B is the first gene for which germline mutations have been demonstrated to predispose to neuroblastoma; and 3) Hirschsprung disease was associated with an intronic single-nucleotide polymorphism of the PHOX2B gene in a case-control study. For clarifying the variable clinical expression of the autonomic nervous system dysfunction observed in neural crest disorders, international databases of clinical symptoms and molecular test results should be established. Furthermore, the development of genetic mouse models should help to improve our understanding of the molecular mechanisms underlying neural crest disorders.


Assuntos
Doença de Hirschsprung/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/fisiologia , Neuroblastoma/genética , Apneia do Sono Tipo Central/congênito , Apneia do Sono Tipo Central/genética , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia , Animais , Estudos de Casos e Controles , Genes Dominantes , Mutação em Linhagem Germinativa , Humanos , Lactente , Recém-Nascido , Camundongos , Mutação , Crista Neural/patologia , Morte Súbita do Lactente/genética
18.
Am J Respir Crit Care Med ; 172(2): 238-43, 2005 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15860752

RESUMO

RATIONALE: Central congenital hypoventilation syndrome (CCHS) is a rare autosomal dominant syndrome present from birth, and characterized by depressed ventilation during sleep. Heterozygous mutations of the homeobox gene Phox2b were recently found in a very high proportion of patients. OBJECTIVES: To determine whether newborn mice with heterozygous targeted deletion of the transcription factor Phox2b would display sleep-disordered breathing. METHODS: We measured breathing pattern using whole-body plethysmography in wild-type and mutant 5-day-old mice, and we classified sleep-wake states using nuchal EMG and behavioral scores. RESULTS: We found that sleep apnea total time was approximately six times longer (8.9 +/- 12 vs. 1.5 +/- 2.2 seconds, p < 0.0015), and ventilation during active sleep was 21% lower (18.4 +/- 5.1 vs. 23.3 +/- 5.5 ml/g/second, p < 0.006) in mutant than in wild-type pups. During wakefulness, apnea time and ventilation were not significantly different between mutant and wild-type pups. Mutant and wild-type pups showed highly similar sleep-wake states. CONCLUSION: Although their respiratory phenotype was much less severe than CCHS, the Phox2b(+/-) mutant mice showed sleep-disordered breathing, which partially modeled the key feature of CCHS.


Assuntos
Animais Recém-Nascidos/metabolismo , Deleção de Genes , Heterozigoto , Proteínas de Homeodomínio/genética , Síndromes da Apneia do Sono/genética , Fatores de Transcrição/genética , Animais , Peso Corporal , Eletromiografia , Camundongos , Respiração , Sono , Síndromes da Apneia do Sono/patologia , Síndromes da Apneia do Sono/fisiopatologia , Fases do Sono , Fatores de Tempo
20.
Chest ; 127(1): 72-9, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15653965

RESUMO

OBJECTIVE: To analyze the main clinical features, genetic mutations, and outcomes of patients of the French Congenital Central Hypoventilation Syndrome (CCHS) Registry. DESIGN: A country-wide cohort established throughout a long-term multicenter effort. PATIENTS: Seventy French patients with CCHS (29 male patients and 41 female patients). METHODS: The following items were analyzed: the most important moments of the disease course; the main clinical characteristics; associated pathologic conditions; management; clinical outcome; and genetic mutations. RESULTS: An average of four new cases of CCHS per year was observed in the last 5 years. Thus, the incidence may be estimated to be 1 per 200,000 live births in France. The median age at diagnosis was 3.5 months (range, 0.5 to 15 months) before 1995 and < 2 weeks in the last 5 years (p = 0.01). CCHS occurred in isolation in 58 of 70 patients. In the remainder, it was associated with Hirschsprung disease (HSCR) [nine patients], Hirschsprung and neural crest tumor (two patients), and growth hormone deficiency (one patient). Among the 50 patients who lived beyond 1 year of age, all but one received nighttime ventilation, with 10 of them (20%) receiving it noninvasively. Three patients (6%) required daytime ventilatory support in addition to nighttime ventilation. The overall mortality rate was 38% (95% confidence interval [CI], 27 to 49%). The median age at death was 3 months (range, 0.4 months to 21 years). The 2-year mortality rate was greater in male patients than in female patients (p = 0.02; relative risk [RR], 2.71; 95% CI, 1.14 to 6.47) but was not affected by HSCR (p = 0.93; RR, 0.95; 95% CI, 0.28 to 3.2). The 43 patients who are currently alive (11 men; sex ratio, 0.4) have a mean age of 9 years (range, 2 months to 27 years). Among the 34 patients tested thus far, heterozygous mutations of the paired-like homeobox gene 2B (PHOX2B) gene were found in 31 patients (91%). CONCLUSION: Our four major findings are the extreme rarity of CCHS, the improved recognition over time, the lack of effect of HSCR on the mortality rate, and the high frequency of PHOX2B mutations.


Assuntos
Proteínas de Homeodomínio/genética , Apneia do Sono Tipo Central/epidemiologia , Apneia do Sono Tipo Central/genética , Fatores de Transcrição/genética , Feminino , França/epidemiologia , Genótipo , Doença de Hirschsprung/epidemiologia , Humanos , Incidência , Masculino , Mutação , Fenótipo , Sistema de Registros , Apneia do Sono Tipo Central/mortalidade
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