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1.
Neuropediatrics ; 51(3): 198-205, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32143222

RESUMO

BACKGROUND: Over 80% of individuals suffering from Rett syndrome (RTT) are affected over their life period by sleeping disorders. Little is known about the impact of those on the quality of life and a clinical approach to the treatment of sleep disturbances is lacking. AIMS: Primary aim was to assess sleep quality in children and adults. Secondary aim was to assess behavioral disorders and their relationship to sleep quality. The medication taken by the subjects was also included. METHODS: Sleep quality and medication were assessed using the sleeping questionnaire for children with neurological and other complex diseases (SNAKE). Behavioral disorders were assessed by the Rett Syndrome Behavior Questionnaire (RSBQ). Questionnaires were sent to the 700 members of the Elternhilfe für Kinder mit Rett Syndrom in Deutschland e.V. (Rett Aid) of which 287 were included. Questionnaires were filled out by the primary caregivers. RESULTS: Sleep quality was rated as very good to good by over 60% of caregivers in contrast to data available in the literature. Behavioral disorders related to regression such as loss of acquired hand skills (p = 0.046) and isolation (p = 0.002) were found to be associated with sleep quality. Melatonin showed a significant association (p = 0.007) with sleep quality. CONCLUSION: Our study showed sleep dysfunction to be less prevalent in RTT-affected individuals than evidence from past studies has suggested. Nevertheless, this remains a subjective assessment of sleep quality and therefore the need to find objective, disorder-specific parameters that measure sleep quality in RTT patients persists.


Assuntos
Sintomas Comportamentais/fisiopatologia , Qualidade de Vida , Síndrome de Rett/fisiopatologia , Transtornos do Sono-Vigília/fisiopatologia , Adolescente , Adulto , Sintomas Comportamentais/diagnóstico , Sintomas Comportamentais/etiologia , Criança , Feminino , Humanos , Masculino , Projetos Piloto , Estudos Prospectivos , Síndrome de Rett/complicações , Síndrome de Rett/diagnóstico , Transtornos do Sono-Vigília/diagnóstico , Transtornos do Sono-Vigília/etiologia , Adulto Jovem
2.
Neuropediatrics ; 39(4): 200-4, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19165707

RESUMO

Drooling is a common and severe problem in children with neurological disorders and is caused by a disturbed coordination of orofacial and palatolingual muscles. Botulinum toxin could be a successful option to reduce excessive sialorrhea in children with neurological disorders. In 30 children with cerebral palsy or neurodegenerative disorder we injected under ultrasound guidance either botulinum toxin A or botulinum toxin B into the parotid and submandibular glands on both sides. All injections were well tolerated without general anaesthesia. Drooling severity at baseline and reduction of sialorrhea during treatment was measured using a parent's questionnaire and rated using the Teachers Drooling Scale (TDS). Reduction of sialorrhea was achieved two weeks after injection, with a positive effect lasting about three to four months in most children. 83% showed a good response to botulinum toxin after first injection, but only in 50% treatment was continued. We found no significant differences between botulinum toxin A or B. Side effects were observed in 5 children with viscous saliva and in one child a unilateral parotitis was observed. Treatment of drooling with botulinum toxin into the salivary glands is a safe and easy therapeutic option for children with neurological disorders to improve life quality.


Assuntos
Antidiscinéticos/uso terapêutico , Toxinas Botulínicas/uso terapêutico , Sialorreia/tratamento farmacológico , Adolescente , Toxinas Botulínicas/classificação , Toxinas Botulínicas Tipo A/uso terapêutico , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Doenças do Sistema Nervoso/complicações , Glândula Parótida/efeitos dos fármacos , Estudos Retrospectivos , Sialorreia/etiologia , Sialorreia/patologia , Glândula Submandibular/efeitos dos fármacos , Ultrassonografia/métodos
3.
Eur J Paediatr Neurol ; 12(1): 51-5, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17625938

RESUMO

Opsoclonus-myoclonus syndrome (OMS) is a rare and debilitating disorder of unknown etiology affecting children and adults. Outcome is unfavourable; approximately 80% of children with OMS suffer from mild to severe neurological handicaps, mainly cognitive impairment. A standard therapy does not exist. Due to the possible immune-mediated mechanisms, treatment with steroids, ACTH, plasmapheresis and immunoglobulins can be successful. However, some children become steroid dependent and symptoms may reoccur after treatment has been finished. We present two girls with OMS, who had a prolonged clinical course lasting 4 and 9 years with many relapses. Both children developed symptoms around the age of two years. Diagnostic work-up to exclude neuroblastoma was negative. Several treatment modalities including oral steroids, dexamethasone pulses, immunoglobulin and cyclosporine were used without lasting success. In addition, cognitive impairment developed in both children. In order to prevent further clinical and mental deterioration, 6 pulses of cyclophosphamide in combination with dexamethasone pulses every 4 weeks were administered. Both children showed significant improvement of OMS symptoms. One girl is still symptom free 18 months after treatment, mild ataxia developed in the other after 12 months. Both children are mentally handicapped and in special need schools. We conclude that combination of cyclophosphamide pulses and dexamethasone pulse therapy is a therapeutic option even after a long clinical course to improve symptoms of OMS.


Assuntos
Anti-Inflamatórios/uso terapêutico , Ciclofosfamida/uso terapêutico , Dexametasona/uso terapêutico , Imunossupressores/uso terapêutico , Síndrome de Opsoclonia-Mioclonia/tratamento farmacológico , Adolescente , Pré-Escolar , Quimioterapia Combinada , Feminino , Escrita Manual , Humanos , Imageamento por Ressonância Magnética , Destreza Motora/efeitos dos fármacos , Síndrome de Opsoclonia-Mioclonia/patologia , Prevenção Secundária
4.
Eur J Paediatr Neurol ; 12(1): 56-60, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17625939

RESUMO

Sandhoff disease (gangliosidosis type 0) is a lysosomal storage disorder with a deficiency of hexosaminidases A and B. After an initially normal development the clinical course of affected children is severe and rapidly progressive leading to spastic tetraparesis, epileptic seizures and early death. In a 10-month-old girl with enzymatically established diagnosis of Sandhoff disease MRI of the brain showed signal changes in the periventricular white matter, pyramidal tract, basal ganglia, and cerebellar hemispheres. Proton MR spectroscopy (MRS) at the age of 13 months revealed a reduction of total N-acetylaspartate (neuroaxonal marker) as well as strongly elevated inositol (glial marker) in white matter, gray matter, and basal ganglia. A new resonance at 2.07 ppm was detected in all regions and ascribed to N-acetylhexosamine with highest concentrations in white matter and thalamus. While conventional MRS findings are in line with neuroaxaonal damage and pronounced astrocytosis, the observation of N-acetylhexosamine appears as a specific marker of Sandhoff disease indicating accumulation of hexosamine-containing oligosaccharides. This interpretation is supported by a recent in vitro MRS study of a Sandhoff mouse model. In conclusion, proton MRS of cerebral metabolites offers specific insights into the pathopysiologic processes of children with Sandhoff disease and may prove to represent another disease specific MRS pattern of the brain.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Hexosaminas/metabolismo , Doença de Sandhoff/patologia , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Prótons , Cintilografia
5.
Eur J Neurol ; 14(4): 387-90, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17388985

RESUMO

Five young children developed slowly progressive hemiparesis as the initial manifestation of Rasmussen encephalitis (RE). Three have remained seizure free over an observational period of 1.3-1.9 years. In the remaining two patients, seizures occurred after 0.5 and 0.6 years respectively. We suggest that RE might be presently underdiagnosed and should be suspected in cases of new onset hemiparesis. In this series, three out of five patients showed oligoclonal bands on examination of cerebrospinal fluid (CSF) which represented additional diagnostic hints towards an immune-mediated condition. According to recently published formal diagnostic criteria, evidence of progressive cerebral hemiatrophy or bioptic identification of RE-typical inflammation confirms the diagnosis in such cases. Long-term immunotherapy is recommended in order to prevent further tissue loss and functional decline.


Assuntos
Encefalite/complicações , Encefalite/diagnóstico , Paresia/etiologia , Convulsões/etiologia , Encéfalo/patologia , Criança , Pré-Escolar , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Bandas Oligoclonais/líquido cefalorraquidiano
6.
Am J Med Genet A ; 140(4): 378-82, 2006 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-16419136

RESUMO

We report on a young woman with Jacobsen syndrome (JBS) who was admitted to our psychiatric department because of a bipolar affective disorder (BPAD). Chromosome analysis was performed due to the fact that she had mental retardation, short stature, and subtle facial anomalies. A deletion of the distal long arm of chromosome 11 was found. A detailed mapping of the deletion breakpoint by quantitative real time PCR revealed a true terminal 11q deletion of approximately 8 Mb corresponding to the karyotype 46,XX,del(11)(q24.2). Polymorphic DNA marker analysis showed that the deletion is located on the paternal chromosome. Additionally, laboratory investigations revealed a low platelet count and magnetic resonance imaging of the brain showed white matter T2 hyperintensities in frontotemporal regions, which are unlikely to result from a demyelinating process as indicated by localized proton magnetic resonance spectroscopy. To our knowledge, this is the first report describing a BPAD in a case with JBS.


Assuntos
Anormalidades Múltiplas/genética , Transtorno Bipolar/genética , Deleção Cromossômica , Cromossomos Humanos Par 11/genética , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Transtornos do Crescimento/genética , Humanos , Hibridização in Situ Fluorescente , Deficiência Intelectual/genética , Cariotipagem , Imageamento por Ressonância Magnética , Contagem de Plaquetas , Transtornos Psicomotores/genética , Radiografia , Síndrome
8.
Neuropediatrics ; 37(5): 291-5, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17236108

RESUMO

Opsoclonus-myoclonus syndrome (OMS) is a rare movement disorder characterized by chaotic eye movements, myoclonus, and ataxia associated with severe irritability. Different treatment modalities including steroids and cyclophosphamide have been tried in the past often with significant side effects and variable success. Here we present 11 children, diagnosed with OMS between 1999 and 2005 and treated with high dose dexamethasone pulses. Main symptoms at presentation were opsoclonus (11/11), ataxia and/or myoclonus (11/11), irritability (10/11) associated with a neuroblastoma in four children. Number of dexamethasone pulses ranged from 6 to 60 pulses. No major side effects were reported. In 6/11 children a complete and sustained remission of OMS symptoms was achieved after 6 to 29 pulses of dexamethasone. Two children from this group have a normal development and no neurological sequelae. Two further children have minor delays in fine- and gross-motor skills. Two children despite a complete recovery of OMS symptoms have persisting developmental problems. 5/11 children still require regular dexamethasone pulses in addition to daily prednisolone (n = 1) or have received cyclophosphamide pulses meanwhile (n = 2). All children continue to have developmental and neurological difficulties. In summary treatment with high dose pulsatile dexamethasone appears to be safe and beneficial in a subgroup of patients with OMS.


Assuntos
Dexametasona/uso terapêutico , Glucocorticoides/uso terapêutico , Síndrome de Opsoclonia-Mioclonia/tratamento farmacológico , Pré-Escolar , Vias de Administração de Medicamentos , Feminino , Humanos , Lactente , Masculino , Testes Neuropsicológicos , Estudos Retrospectivos
9.
Neurology ; 65(5): 701-6, 2005 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-16157902

RESUMO

BACKGROUND: Pelizaeus-Merzbacher disease (PMD) is a rare X-linked recessive neurologic disorder caused by a mutation in the proteolipid protein (PLP) gene on chromosome Xq22. The associated depletion of PLP and severe reduction of other major myelin proteins results in dysmyelination. MRI reveals loss of T1 contrast between gray and affected white matter and T2 hyperintensities of white matter due to elevated water content. METHODS: In vivo proton magnetic resonance spectroscopy (MRS) was used to determine cerebral metabolite patterns in five patients with genetically proven PMD. Absolute metabolite concentrations were obtained in cortical gray matter, affected white matter, and basal ganglia and compared to age-matched control values. RESULTS: In comparison to age-matched controls, MRS of affected white matter resembled the metabolite pattern of cortical gray matter, as indicated by increased concentrations of N-acetylaspartate and N-acetylaspartylglutamate (tNAA), glutamine (Gln), myo-inositol (Ins), and creatine and phosphocreatine. Most remarkably, the concentration of choline-containing compounds was reduced. Parietal gray matter and basal ganglia appeared normal but showed a tendency for elevated tNAA, Gln, and Ins. CONCLUSIONS: Magnetic resonance spectroscopy (MRS)-detected alterations are consistent with enhanced neuroaxonal density, astrogliosis, and reduction of oligodendroglia. These disturbances in cellular composition are in close agreement with the histopathologic features characteristic of dys- and hypomyelination. The proton MRS profile of Pelizaeus-Merzbacher disease (PMD) differs from the pattern commonly observed in demyelinating disorders and allows PMD to be distinguished from other leukodystrophies.


Assuntos
Encéfalo/metabolismo , Espectroscopia de Ressonância Magnética , Fibras Nervosas Mielinizadas/metabolismo , Doença de Pelizaeus-Merzbacher/diagnóstico , Doença de Pelizaeus-Merzbacher/metabolismo , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Gânglios da Base/metabolismo , Gânglios da Base/patologia , Gânglios da Base/fisiopatologia , Encéfalo/patologia , Encéfalo/fisiopatologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Criança , Pré-Escolar , Colina/metabolismo , Creatina/metabolismo , Dipeptídeos/metabolismo , Regulação para Baixo/fisiologia , Glutamina/metabolismo , Humanos , Lactente , Inositol/metabolismo , Masculino , Fibras Nervosas Mielinizadas/patologia , Doença de Pelizaeus-Merzbacher/fisiopatologia , Fosfocreatina/metabolismo , Valor Preditivo dos Testes , Prótons , Regulação para Cima/fisiologia
10.
Neurology ; 62(6): 984-6, 2004 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-15037707

RESUMO

Severe focal epilepsy is regarded as a clinical hallmark of Rasmussen encephalitis (RE). The authors report two children with progressive hemiparesis, contralateral hemispheric atrophy, and pathologic features characteristic for RE. At histologic diagnosis and over several months, neither patient experienced seizures. The report enlarges the clinical spectrum of RE and suggests that seizures are not an obligatory presenting symptom of the disorder.


Assuntos
Encefalite/diagnóstico , Convulsões/etiologia , Idade de Início , Atrofia/diagnóstico , Atrofia/etiologia , Atrofia/patologia , Biópsia , Criança , Progressão da Doença , Eletroencefalografia , Encefalite/complicações , Encefalite/tratamento farmacológico , Encefalite/patologia , Feminino , Lateralidade Funcional , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Técnicas In Vitro , Imageamento por Ressonância Magnética , Masculino , Debilidade Muscular/etiologia , Paresia/tratamento farmacológico , Paresia/etiologia
11.
Neuropediatrics ; 34(5): 237-46, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-14598229

RESUMO

About 35-40 % of boys with X-linked adrenoleukodystrophy (ALD) develop a rapidly progressive cerebral form which leads to severe neurologic disability and death within 3-5 years after onset of clinical symptoms. Because previous proton magnetic resonance spectroscopy (MRS) studies of ALD identified metabolite patterns characteristic of demyelination, gliosis, and neuroaxonal loss, this work tested the hypothesis that MRS--apart from indicating disease progression--provides criteria for the outcome after hematopoietic stem cell transplantation (HSCT) which has been promising at an early stage of the active disease. Follow-up quantitative proton MRS was performed in frontal and occipital white matter of ALD patients (n = 12) before and up to 5 years after HSCT. The observed metabolite alterations were retrospectively correlated with the clinical outcome representing either a stable condition (n = 5), a further deterioration (n = 5), or death (n = 2). While disease progression of patients before HSCT was mainly characterized by a further increase of elevated choline-containing compounds (Cho) as an indicator of active demyelination, a positive outcome after HSCT was correlated with high N-acetylaspartate (tNAA) levels in affected white matter before HSCT yielding positive and negative predictive values for tNAA of 80 %. Although to be confirmed in a larger cohort of patients, the present findings suggest the preservation of neuroaxonal integrity as a prerequisite for an arrested course. Conversely, the combination of increased Cho with markedly reduced tNAA before HSCT apparently reflects a degree of tissue degeneration which precludes a successful therapeutic intervention.


Assuntos
Adrenoleucodistrofia/diagnóstico , Adrenoleucodistrofia/metabolismo , Ácido Aspártico/análogos & derivados , Encéfalo/metabolismo , Encéfalo/cirurgia , Transplante de Células-Tronco Hematopoéticas/métodos , Espectroscopia de Ressonância Magnética/métodos , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios , Prótons , Adrenoleucodistrofia/fisiopatologia , Ácido Aspártico/metabolismo , Encéfalo/fisiopatologia , Criança , Seguimentos , Humanos , Masculino , Regeneração Nervosa/fisiologia , Valor Preditivo dos Testes , Índice de Gravidade de Doença , Resultado do Tratamento
12.
Neurology ; 60(5): 819-25, 2003 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-12629240

RESUMO

BACKGROUND: Krabbe disease (globoid cell leukodystrophy [GLD]) is an autosomal recessive lysosomal disorder affecting the central and peripheral nervous system. The authors performed MRS to characterize metabolic alterations and their regional variation in brain tissue in GLD in vivo. METHODS: Abnormalities of cerebral metabolite concentrations were assessed in seven patients with biochemically proven GLD-four with infantile, two with juvenile, and one with adult subtype-using quantitative localized proton MRS of standardized brain regions. RESULTS: In infantile GLD, pronounced elevation of both myo-inositol and choline-containing compounds in affected white matter reflected demyelination and glial proliferation. The accompanying decrease of N-acetylaspartate pointed to neuroaxonal loss. Gray matter showed similar, albeit much milder alterations. In juvenile GLD, MRS indicated astrocytosis with minor neuroaxonal damage in white matter. In a patient with adult GLD, results of MRS of affected white matter were close to normal. MRS data are in agreement with histopathologic features of GLD. CONCLUSION: Proton MRS provides a powerful tool for assessing metabolic disturbances and the extent of brain damage noninvasively in GLD.


Assuntos
Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Encéfalo/metabolismo , Colina/metabolismo , Inositol/metabolismo , Leucodistrofia de Células Globoides/diagnóstico , Leucodistrofia de Células Globoides/metabolismo , Espectroscopia de Ressonância Magnética , Fosfocreatina/análogos & derivados , Adulto , Gânglios da Base/metabolismo , Criança , Pré-Escolar , Creatinina/metabolismo , Dipeptídeos/metabolismo , Feminino , Seguimentos , Humanos , Lactente , Lactatos/metabolismo , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Lobo Parietal/metabolismo , Lobo Parietal/patologia , Fosfocreatina/metabolismo
13.
Anal Chem ; 74(5): 1197-201, 2002 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11924985

RESUMO

The benefits of high-throughput bioanalysis within the pharmaceutical industry are well established. One of the most significant bottlenecks in bioanalysis is transferring in vivo-generated study samples from their collection tubes during sample preparation and extraction. In most cases, the plasma samples must be stored frozen prior to analysis, and the freeze/thaw (F/T) process introduces thrombin clots that are capable of plugging pipets and automated liquid-transfer systems. A new approach to dealing with this problem involves the use of Ansys Captiva 96-well 20-microm polypropylene filter plates to collect, store frozen, and filter plasma samples prior to bioanalysis. The samples are collected from the test subjects, and the corresponding plasma samples are placed directly into the wells of the filter plate. Two Duoseal (patent pending) covers are used to seal the top and bottom of the plate, and the plate is stored at down to -70 degrees C. Prior to sample analysis, the seals are removed and the plate is placed in a 96-well SPE manifold. As the plasma thaws, it passes (by gravity or mild vacuum) through the polypropylene filter into a 96-well collection plate. A multichannel pipet or automated liquid-transfer system is used to transfer sample aliquots without fear of plugging. A significant advantage of this approach is that, unlike other methods, issues related to incomplete pipetting are virtually eliminated. The entire process is rapid since thawing and filtering take place simultaneously, and if a second F/T cycle is required for reanalysis, it is not necessary to refilter the samples (additional clotting was not observed after three F/T cycles). This technique was tested using monkey, rat, and dog plasma and sodium heparin and EDTA anticoagulants. To assess the possibility of nonspecific binding to the polypropylene filter, a variety of drug candidates from diverse drug classes were studied. Validation data generated for two Lilly compounds from distinct classes, before and after filtering, are presented in this paper as practical examples of this technique. While LC/MS/MS is the primary method of bioanalysis in our laboratory, the technique presented in this paper is applicable to other forms of detection as well.


Assuntos
Autoanálise/métodos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Filtração , Preparações Farmacêuticas/análise , Solventes , Manejo de Espécimes
14.
Neuropediatrics ; 33(6): 327-30, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12571790

RESUMO

OBJECTIVES: The present study investigates the effect of topical injections of botulinum toxin A into the cephalic salivary glands of children with chronic hypersalivation due to neurodegenerative diseases. METHODS: Five children with hypersalivation due to severe neurological diseases received, under ultrasound guidance, a total of 50-65 units of botulinum toxin A (Botox) into the parotid and submandibular glands on both sides. All injections were tolerated without local anaesthesia. Before and 1, 2, 4, 8 and 12 weeks after toxin injection, salivary flow rates and the concentrations of total protein, alpha-amylase, acid phosphatase, kallikrein, and immunoglobulin A were measured in the secretions; simultaneously, the patients were clinically examined with regard to severity of symptoms, and their salivary glands were subjected to ultrasound study. RESULTS: A distinct improvement of symptoms within the first 2 weeks following toxin administration were reported by the parents. Sialometry revealed considerably reduced flow rates but sialochemistry showed an increase of amylase activity. Ultrasound examination did not reveal any changes of the salivary parenchyma, and side-effects were absent. CONCLUSION: Treatment of drooling by topical injection of botulinum toxin A into the salivary glands is a reliable and also side-effect-free therapeutic option for children with neurological disorders. All children involved in our study experienced a distinct improvement of their quality of life.


Assuntos
Toxinas Botulínicas Tipo A/administração & dosagem , Doenças Neurodegenerativas/complicações , Glândula Parótida/efeitos dos fármacos , Sialorreia/tratamento farmacológico , Glândula Submandibular/efeitos dos fármacos , Adolescente , Criança , Feminino , Humanos , Injeções Subcutâneas , Masculino , Salivação/efeitos dos fármacos , Sialorreia/etiologia , Resultado do Tratamento
15.
J Appl Physiol (1985) ; 89(5): 2015-22, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11053357

RESUMO

Aminophylline is a respiratory stimulant commonly used for the treatment of central apnea. Experiences from clinical practice, however, revealed that aminophylline is not reliably effective in preterm infants, whereas it is normally effective in infants and mature patients. In an established animal model for postnatal development of respiratory control mechanisms, we therefore examined the hypothesis that the clinical observations reflect a developmental change in the sensitivity of the central respiratory network to methylxanthines. The medullary respiratory network was isolated at different postnatal ages (postnatal days 1-13; P1-P13) in a transverse mouse brain stem slice preparation. This preparation contains the pre-Bötzinger complex (PBC), a region that is critical for generation of respiratory rhythm. Spontaneous rhythmic respiratory activity was recorded from the hypoglossal (XII) rootlets and from neurons in the PBC by using the whole cell patch clamp technique. Bath-applied aminophylline [20 microM] increased the frequency (+41%) in neonatal animals (P1-P6) without affecting the amplitude of respiratory burst activity in XII rootlets. The same concentration of aminophylline did not have any significant effect on the frequency of respiratory XII bursts but increased the amplitude (+31%) in juvenile animals (P7-P13). In the same age group, aminophylline also augmented the amplitude and the duration of respiratory synaptic drive currents in respiratory PBC neurons. The data demonstrate that augmentation of the respiratory output is due to direct enhancement of central respiratory network activity and increase of synaptic drive of hypoglossal motoneurons in juvenile, but not neonatal, animals. This indicates a developmental change in the efficacy of aminophylline to reinforce central respiratory network activity. Therefore, we believe that the variable success in treating respiratory disturbances in premature infants reflects maturational changes in the expression of receptors and/or intracellular signal pathways in the central respiratory network.


Assuntos
Aminofilina/farmacologia , Broncodilatadores/farmacologia , Centro Respiratório/efeitos dos fármacos , Centro Respiratório/crescimento & desenvolvimento , Fatores Etários , Animais , Animais Recém-Nascidos , Apneia/tratamento farmacológico , Feminino , Nervo Hipoglosso/crescimento & desenvolvimento , Nervo Hipoglosso/fisiologia , Masculino , Camundongos , Técnicas de Cultura de Órgãos , Mecânica Respiratória/efeitos dos fármacos , Mecânica Respiratória/fisiologia
16.
Int J Cancer ; 89(5): 395-402, 2000 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-11008200

RESUMO

To identify prognostic factors in medulloblastoma, a common malignant brain tumor of childhood, expression of the oncogene c-myc was examined at the mRNA level by in situ hybridization. c-myc mRNA expression was observed in 30 of 72 tumors (42%). The c-myc gene copy number was determined by quantitative PCR from genomic DNA of paraffin-embedded tumors. c-myc gene amplification was present in 5 of 62 cases (8.3%). Therefore, c-myc amplification was obviously not the cause of c-myc mRNA expression in most samples. Kaplan-Meier estimation revealed a significant correlation between c-myc mRNA expression and survival (total mean follow-up 4.6 +/- 3.6 years, log-rank p = 0.02). Multivariate logistic regression analysis including sex, age, histological type, degree of surgical resection and expression of synaptophysin, GFAP and c-myc, was carried out on 54 patients who received both radiotherapy and chemotherapy. The analysis identified expression of c-myc as an independent predictive factor of death from disease.


Assuntos
Neoplasias Cerebelares/genética , Genes myc , Meduloblastoma/genética , Adolescente , Adulto , Neoplasias Cerebelares/mortalidade , Neoplasias Cerebelares/patologia , Criança , Pré-Escolar , Feminino , Dosagem de Genes , Humanos , Lactente , Masculino , Meduloblastoma/mortalidade , Meduloblastoma/patologia , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
17.
Pediatr Neurol ; 23(1): 22-31, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10963966

RESUMO

The diagnostic value of single-voxel proton magnetic resonance spectroscopy (2 T, stimulated echo acquisition mode, TR = 6,000 ms, TE = 20 ms, 4-5 mL volumes-of-interest) was assessed for a differentiation of focal brain lesions of unknown etiology in 17 patients 1-14 years of age. Absolute metabolite concentrations were compared with age-matched control subjects and an individual control region. Most of the brain tumors were characterized by strongly reduced total N-acetylaspartyl compounds and marked increases of myo-inositol and choline-containing compounds, consistent with a lack of neuroaxonal tissue and a proliferation of glial cells. Lactate was elevated in only four patients. When using this pattern for a metabolic discrimination of brain tumors from other focal lesions, proton spectroscopy correctly identified 14 of 17 abnormalities, as confirmed by histologic examination after neurosurgical intervention. One false-positive tumor diagnosis was a severe reactive gliosis mimicking a typical tumor spectrum. Two inconclusive cases comprised an astrocytoma with moderately elevated myo-inositol but reduced choline-containing compounds and a patient with an abscess leading to a marked reduction of all metabolites but strong contributions from mobile lipids. In summary, quantitative proton spectroscopy has considerable clinical value for preoperative characterization of focal brain lesions.


Assuntos
Biomarcadores Tumorais/metabolismo , Encefalopatias/diagnóstico , Encefalopatias/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Espectroscopia de Ressonância Magnética , Adolescente , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Biomarcadores Tumorais/análise , Abscesso Encefálico/diagnóstico , Abscesso Encefálico/metabolismo , Encefalopatias/etiologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/metabolismo , Estudos de Casos e Controles , Criança , Pré-Escolar , Colina/análogos & derivados , Colina/metabolismo , Creatina/análogos & derivados , Creatina/metabolismo , Diagnóstico Diferencial , Feminino , Glioma/diagnóstico , Glioma/metabolismo , Gliose/diagnóstico , Gliose/metabolismo , Humanos , Lactente , Inositol/metabolismo , Ácido Láctico/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Masculino , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/metabolismo , Valor Preditivo dos Testes
18.
Arch Dis Child Fetal Neonatal Ed ; 82(3): F224-7, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10794791

RESUMO

BACKGROUND: Sufficient ATP concentrations maintain physiological processes and protect tissue from hypoxic damage. With decreasing oxygen concentration, ATP synthesis relies increasingly on the presence of phosphocreatine. AIM: The effect of exogenously applied creatine on phosphocreatine and ATP concentrations was studied under control and anoxic conditions. METHODS: Pregnant mice were fed orally with creatine monohydrate (2 g/kg body weight/day). Brainstem slices from these mice pups were compared with those from pups of non-creatine supplemented pregnant mice. Measurements were performed under normoxic and anoxic conditions. In addition, brainstem slices from non-creatine treated mice pups were incubated for 3 hours in control artificial cerebrospinal fluid (CSF) (n = 10) or in artificial CSF containing 200 microM creatine (n = 10). ATP and phosphocreatine contents were determined enzymatically in single brainstem slices. RESULTS: ATP concentrations were in the same range in all preparations. However, there was a significant increase of phosphocreatine in the brainstems from pups of creatine fed mice when compared with the brainstems of pups from non-creatine treated mice or in non-incubated brainstems of control animals. After 30 minutes anoxia, ATP as well as phosphocreatine concentrations remained significantly higher in creatine pretreated slices compared with controls. CONCLUSION: The data indicate that exogenous application of creatine is effective in neuroprotection.


Assuntos
Trifosfato de Adenosina/deficiência , Tronco Encefálico/efeitos dos fármacos , Creatina/uso terapêutico , Hipóxia Encefálica/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Fosfocreatina/metabolismo , Trifosfato de Adenosina/biossíntese , Administração Oral , Animais , Animais Recém-Nascidos , Tronco Encefálico/metabolismo , Creatina/metabolismo , Feminino , Hipóxia Encefálica/metabolismo , Camundongos , Fármacos Neuroprotetores/metabolismo , Gravidez
19.
Nature ; 404(6778): 576-8, 2000 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-10766234

RESUMO

Remote sensing observations and the direct sampling of material from a few comets have established the characteristic composition of cometary gas. This gas is ionized by solar ultraviolet radiation and the solar wind to form 'pick-up' ions, ions in a low ionization state that retain the same compositional signatures as the original gas. The pick-up ions are carried outward by the solar wind, and they could in principle be detected far from the coma (Sampling of pick-up ions has also been used to study interplanetary dust, Venus' tail and the interstellar medium.) Here we report the serendipitous detection of cometary pick-up ions, most probably associated with the tail of comet Hyakutake, at a distance of 3.4 AU from the nucleus. Previous observations have provided a wealth of physical and chemical information about a small sample of comets, but this detection suggests that remote sampling of comet compositions, and the discovery of otherwise invisible comets, may be possible.

20.
Z Geburtshilfe Neonatol ; 204(1): 14-9, 2000.
Artigo em Alemão | MEDLINE | ID: mdl-10721181

RESUMO

BACKGROUND: Brainstem auditory evoked response (BAER) is a sensitive test of the functional integrity of the auditory pathway. Latencies and amplitudes of measured waveforms reflect maturation of this brainstem pathway and may allow a prediction for neurological outcome. PATIENTS AND METHODS: BAER were measured prospectively in preterm infants with a birthweight less than 1500 g at 3 to 4 day following birth and during treatment on neonatal intensive care unit (NICU) every two weeks. Pre- and postnatal risk factors and frequency of apnea were evaluated. Outcome was scored after 1 year corrected age by neurological examination. RESULTS: There were no significant differences in latencies of waves between 5 children with severe asphyxia and/or IVH resulting in major neurological handicaps after 1 year. However, two of these children have bilateral abnormalities. The slope of decay of wave latencies decreased between 30 and 32 weeks gestational age, while the number of registered apnea increased. In follow up investigations during treatment on NICU there was a decrease in interpeak latencies wave V to wave III from 24/25 weeks gestational age to term infants and increase in amplitudes. CONCLUSION: Early performed BAER alone is not a good predictor for neurological outcome of preterm infants because of great interindividual variability of normal neonates and the anatomical site of cerebral lesions. The method contributes information on the brainstem maturation and may also reflect the different maturational stages of the respiratory system.


Assuntos
Asfixia Neonatal/diagnóstico , Dano Encefálico Crônico/diagnóstico , Hemorragia Cerebral/diagnóstico , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Recém-Nascido de muito Baixo Peso/fisiologia , Asfixia Neonatal/fisiopatologia , Dano Encefálico Crônico/fisiopatologia , Tronco Encefálico/fisiopatologia , Hemorragia Cerebral/fisiopatologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Prognóstico , Tempo de Reação/fisiologia , Valores de Referência
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