Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
1.
Sci Eng Ethics ; 26(6): 2975-2984, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32696430

RESUMO

Rapid advancements in machine learning techniques allow mass surveillance to be applied on larger scales and utilize more and more personal data. These developments demand reconsideration of the privacy-security dilemma, which describes the tradeoffs between national security interests and individual privacy concerns. By investigating mass surveillance techniques that use bulk data collection and machine learning algorithms, we show why these methods are unlikely to pinpoint terrorists in order to prevent attacks. The diverse characteristics of terrorist attacks-especially when considering lone-wolf terrorism-lead to irregular and isolated (digital) footprints. The irregularity of data affects the accuracy of machine learning algorithms and the mass surveillance that depends on them which can be explained by three kinds of known problems encountered in machine learning theory: class imbalance, the curse of dimensionality, and spurious correlations. Proponents of mass surveillance often invoke the distinction between collecting data and metadata, in which the latter is understood as a lesser breach of privacy. Their arguments commonly overlook the ambiguity in the definitions of data and metadata and ignore the ability of machine learning techniques to infer the former from the latter. Given the sparsity of datasets used for machine learning in counterterrorism and the privacy risks attendant with bulk data collection, policymakers and other relevant stakeholders should critically re-evaluate the likelihood of success of the algorithms and the collection of data on which they depend.


Assuntos
Privacidade , Terrorismo , Big Data , Coleta de Dados , Humanos , Aprendizado de Máquina
2.
Eur J Neurol ; 25(5): 782-786, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29443442

RESUMO

BACKGROUND AND PURPOSE: Acute disseminated encephalomyelitis followed by optic neuritis (ADEM-ON) is a rare demyelinating syndrome that is different from multiple sclerosis and neuromyelitis optica spectrum disorder. The aim of this study was to describe the disease course, treatment response and outcome of children with ADEM-ON. METHODS: Children of <18 years of age were identified from six countries of the EU Paediatric Demyelinating Disease Consortium. Patients fulfilled the diagnostic criteria for ADEM followed by at least one ON. Anti-myelin oligodendrocyte glycoprotein (MOG) antibodies were tested in all patients. RESULTS: In this study of 17 patients (nine boys) with ADEM-ON, anti-myelin oligodendrocyte glycoprotein (MOG) antibodies were identified in 16 patients. Age at onset was 6.1 years (interquartile range, 5.1-9.2 years). Twelve patients received oral prednisolone and 10 received maintenance immunosuppression (e.g. azathioprine, intravenous immunoglobulins, Rituximab). During a follow-up of 5.3 years (interquartile range, 1.8-10.2 years), 54 relapses occurred with a median of 3 relapses per patient (range, 1-9 per patient). Patients relapsed on all treatments but no relapses occurred on a prednisolone dose >10 mg/day. Visual and cognitive residual deficits were common in this group. CONCLUSIONS: Acute disseminated encephalomyelitis followed by optic neuritis is an anti-MOG antibody-associated relapsing disorder that can have a heterogeneous disease course. Patients were refractory for maintenance immunosuppression and appeared to be corticosteroid-dependent. Further international collaborations are now required to unify guidelines in this difficult-to-manage group of patients.


Assuntos
Encefalomielite Aguda Disseminada/diagnóstico , Imunoglobulinas Intravenosas/uso terapêutico , Imunossupressores/uso terapêutico , Neurite Óptica/diagnóstico , Adolescente , Autoanticorpos , Azatioprina/uso terapêutico , Criança , Pré-Escolar , Progressão da Doença , Encefalomielite Aguda Disseminada/tratamento farmacológico , Encefalomielite Aguda Disseminada/imunologia , Feminino , Humanos , Masculino , Glicoproteína Mielina-Oligodendrócito/imunologia , Neurite Óptica/tratamento farmacológico , Neurite Óptica/imunologia , Prednisolona/uso terapêutico , Rituximab/uso terapêutico , Resultado do Tratamento
3.
Clin Genet ; 85(2): 178-83, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23495813

RESUMO

Dominant mutations in TUBB2B have been reported in patients with polymicrogyria. We further explore the phenotype associated with mutations in TUBB2B. Twenty patients with polymicrogyria (five unilateral) were tested for mutations in TUBB2B by Sanger sequencing. We identified two novel de novo mutations, c.743C>T (p.Ala248Val) and c.1139G>T (p.Arg380Leu) in exon 4 of TUBB2B in three unrelated families. Brain magnetic resonance images showed polymicrogyria involving predominantly the perisylvian regions. In addition, there was a dysmorphic appearance of the basal ganglia, thin corpus callosum, enlargement of the ventricles, thinning of the white matter and hypoplasia of pons and cerebellar vermis. This combination of associated features was absent in all 17 patients with polymicrogyria in whom no mutation was identified. This report underlines that the association of polymicrogyria with thin or absent corpus callosum, dysmorphic basal ganglia, brainstem and vermis hypoplasia is highly likely to result from mutations in TUBB2B and provides further insight in how mutations in TUBB2B affect protein function.


Assuntos
Gânglios da Base/patologia , Modelos Moleculares , Fenótipo , Polimicrogiria/genética , Polimicrogiria/patologia , Tubulina (Proteína)/genética , Sequência de Bases , Análise Mutacional de DNA , Dineínas/química , Dineínas/metabolismo , Genes Dominantes/genética , Humanos , Imageamento por Ressonância Magnética , Dados de Sequência Molecular
4.
Int J Colorectal Dis ; 28(11): 1547-53, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23811983

RESUMO

PURPOSE: This study evaluates colon transit time (CTT) and anorectal manometry (ARM) in spina bifida (SB) patients in relation to the level of lesion, mobility, constipation, and continence status. METHODS: SB patients between 6 and 19 years, who are not using antegrade continence enemas and followed at the SB Reference Centre UZ Ghent, were asked to participate. Medical history was retrospectively retrieved from the medical file. Stool habits were prospectively collected using standardized questionnaires. CTT was measured using the 6-day pellet abdominal X-ray method. ARM was performed in non-sedated children with a water-perfused, latex-free catheter. RESULTS: Forty out of 52 eligible patients consented to perform CTT, of which 19 also performed the ARM. Fifteen (37 %) SB patients were constipated despite treatment. Twenty-six (65 %) were (pseudo) continent. The total CTT was significantly prolonged in SB patients (median CTT 86.4 vs. 36 h controls). The CTT was significantly prolonged in constipated SB patients compared to non-constipated SB patients (122.4 vs. 52.8 h). Spontaneously continent patients had a normal CTT (33.6 h) as well as a significantly higher resting pressure compared to the pseudo-continent and incontinent SB patients (resting pressure 56.5 vs. 32.5 mmHg). An abnormal CTT was associated with a treatment necessity to achieve pseudo-continence (p = 0.006). CONCLUSION: CTT in SB patients was significantly prolonged, indicating a neurogenic involvement of the bowel and slow transit constipation. SB patients with a normal CTT and a normal ARM spontaneously achieved fecal continence. CTT can help tailor the continence therapy in SB patients.


Assuntos
Canal Anal/fisiopatologia , Colo/fisiopatologia , Trânsito Gastrointestinal/fisiologia , Reto/fisiopatologia , Disrafismo Espinal/fisiopatologia , Adolescente , Criança , Feminino , Humanos , Masculino , Manometria , Fatores de Tempo , Adulto Jovem
5.
Arch Pediatr ; 20(8): 831-6, 2013 Aug.
Artigo em Francês | MEDLINE | ID: mdl-23849474

RESUMO

INTRODUCTION: Patients with open spinal dysraphism (OSD) frequently present constipation and incontinence requiring treatment. AIM: Evaluation of colon transit time (CTT) in patients with OSD, in relation to neural lesion, mobility, bowel habits, and continence status. METHODS: OSD patients aged between 6 and 20 years, who did not use antegrade enemas, were invited to participate in the study. Data from the medical file and information retrieved by questionnaires for constipation and incontinence were collected. The control group consisted of 13 healthy age-matched children. CTT was measured using the 6-day pellet method with an abdominal X-ray on day 7. Laxatives were continued and retrograde colon enemas were stopped 48h prior the X-ray. RESULTS: Thirty of the 33 patients who met the inclusion criteria agreed to participate. Twelve (40%) patients were constipated (Rome III criteria) despite treatment. Fifteen (50%) were continent, with or without treatment. Total CTT was significantly longer in OSD patients (median CTT: 86.4h vs. 43.2h controls). Constipated OSD patients had a significantly prolonged CTT compared to non-constipated patients (CTT: 125.4h vs. 51.6h). Spontaneous continent OSD patients had a normal CTT (CTT: 33.6h). An abnormal CTT predicted the necessity of treatment to achieve continence (P<0.006). CONCLUSION: CTT in OSD patients is significantly prolonged, indicating a neurogenic involvement of the bowel and a slow transit constipation. An abnormal CTT predicts the necessity of therapy to achieve fecal continence.


Assuntos
Colo/fisiopatologia , Trânsito Gastrointestinal/fisiologia , Espinha Bífida Cística/fisiopatologia , Adolescente , Criança , Colo Ascendente/fisiopatologia , Colo Descendente/fisiopatologia , Colo Sigmoide/fisiopatologia , Constipação Intestinal/fisiopatologia , Defecação/fisiologia , Enema , Impacção Fecal/fisiopatologia , Incontinência Fecal/fisiopatologia , Feminino , Humanos , Laxantes/uso terapêutico , Masculino , Estudos Prospectivos , Fatores de Tempo , Adulto Jovem
6.
Neurogenetics ; 14(1): 23-34, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23334464

RESUMO

Epilepsy and mental retardation limited to females (EFMR), caused by PCDH19 mutations, has a variable clinical expression that needs further exploration. Onset of epilepsy may be provoked by fever and can resemble Dravet syndrome. Furthermore, transmitting males have no seizures, but are reported to have rigid personalities suggesting possible autism spectrum disorders (ASD). Therefore, this study aimed to determine the phenotypic spectrum associated with PCDH19 mutations in Dravet-like and EFMR female patients and in males with ASD. We screened 120 females suffering from Dravet-like epilepsy, 136 females with EFMR features and 20 males with ASD. Phenotypes and genotypes of the PCDH19 mutation carriers were compared with those of 125 females with EFMR reported in the literature. We report 15 additional patients with a PCDH19 mutation. Review of clinical data of all reported patients showed that the clinical picture of EFMR is heterogeneous, but epilepsy onset in infancy, fever sensitivity and occurrence of seizures in clusters are key features. Seizures remit in the majority of patients during teenage years. Intellectual disability and behavioural disturbances are common. Fifty percent of all mutations are missense mutations, located in the extracellular domains only. Truncating mutations have been identified in all protein domains. One ASD proband carried one missense mutation predicted to have a deleterious effect, suggesting that ASD in males can be associated with PCDH19 mutations.


Assuntos
Caderinas/genética , Transtornos Globais do Desenvolvimento Infantil/epidemiologia , Transtornos Globais do Desenvolvimento Infantil/genética , Epilepsia/epidemiologia , Epilepsia/genética , Mutação/fisiologia , Adolescente , Caderinas/fisiologia , Criança , Transtornos Globais do Desenvolvimento Infantil/complicações , Pré-Escolar , Estudos de Coortes , Epilepsias Mioclônicas/epidemiologia , Epilepsias Mioclônicas/genética , Epilepsia/complicações , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Deficiência Intelectual/complicações , Deficiência Intelectual/epidemiologia , Deficiência Intelectual/genética , Masculino , Penetrância , Protocaderinas , Caracteres Sexuais , Síndrome
7.
J Urol ; 189(1): 300-4, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23174228

RESUMO

PURPOSE: We studied the use of colon enemas in achieving fecal pseudocontinence in patients with spina bifida to define the variables associated with success. MATERIALS AND METHODS: Questionnaires were individually filled out by all patients with spina bifida using colon enemas at our Spina Bifida Reference Center between October 2009 and June 2010. Patient age, type of enema, volume required, evacuation time, followup, continence and independence were recorded. Fecal pseudocontinence was defined as no involuntary stool loss during the last 6 months. Social continence was defined as involuntary stool loss less than once monthly. Children are routinely seen at the reference center, while adults are seen on request. RESULTS: A total of 25 children and 15 adults with spina bifida were studied. Median volume required was 1 liter (range 0.5 to 2) in children and 1.5 liters (0.75 to 3) in adults. Median evacuation time was 30 minutes (range 15 to 60) in children and 60 minutes (30 to 120) in adults. Fecal continence was achieved in 76% of children (19 of 25) and 60% of adults (9 of 15), and social continence in 88% of children (23 of 25) and 67% of adults (10 of 15). A significant relation was found between medical followup since childhood and fecal pseudocontinence. No enema determinants predicted pseudocontinence. CONCLUSIONS: Colon enemas are a valuable method in achieving continence. At our center medical followup from childhood to adulthood is associated with successful acquisition of fecal pseudocontinence.


Assuntos
Enema , Incontinência Fecal/etiologia , Incontinência Fecal/terapia , Disrafismo Espinal/complicações , Adolescente , Adulto , Criança , Pré-Escolar , Colo , Humanos , Pessoa de Meia-Idade , Adulto Jovem
8.
Neurology ; 76(11): 988-92, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21403111

RESUMO

BACKGROUND: Mutations in the TUBA1A gene have been reported in patients with lissencephaly and perisylvian pachygyria. METHODS: Twenty-five patients with malformations of cortical development ranging from lissencephaly to polymicrogyria were screened for mutations in TUBA1A. RESULTS: Two novel heterozygous missense mutations in TUBA1A were identified: c.629A>G (p.Tyr210Cys) occurring de novo in a boy with lissencephaly, and c.13A>C (p.Ile5Leu) affecting 2 sisters with polymicrogyria whose mother presented somatic mosaicism for the mutation. CONCLUSIONS: Mutations in TUBA1A have been described in patients with lissencephaly and pachygyria. We report a mutation in TUBA1A as a cause of polymicrogyria. So far, all mutations in TUBA1A have occurred de novo, resulting in isolated cases. This article describes familial recurrence of TUBA1A mutations due to somatic mosaicism in a parent. These findings broaden the phenotypic spectrum associated with TUBA1A mutations and have implications for genetic counseling.


Assuntos
Córtex Cerebral/anormalidades , Malformações do Desenvolvimento Cortical/genética , Tubulina (Proteína)/genética , Adulto , Criança , Feminino , Testes Genéticos , Humanos , Lactente , Masculino , Malformações do Desenvolvimento Cortical/patologia , Mutação de Sentido Incorreto
9.
Eur J Med Genet ; 52(2-3): 77-87, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19306953

RESUMO

Array CGH (comparative genomic hybridization) screening of large patient cohorts with mental retardation and/or multiple congenital anomalies (MR/MCA) has led to the identification of a number of new microdeletion and microduplication syndromes. Recently, a recurrent copy number variant (CNV) at chromosome 16p11.2 was reported to occur in up to 1% of autistic patients in three large autism studies. In the screening of 4284 patients with MR/MCA with various array platforms, we detected 22 individuals (14 index patients and 8 family members) with deletions in 16p11.2, which are genomically identical to those identified in the autism studies. Though some patients shared a facial resemblance and a tendency to overweight, there was no evidence for a recognizable phenotype. Autism was not the presenting feature in our series. The assembled evidence indicates that recurrent 16p11.2 deletions are associated with variable clinical outcome, most likely arising from haploinsufficiency of one or more genes. The phenotypical spectrum ranges from MR and/or MCA, autism, learning and speech problems, to a normal phenotype.


Assuntos
Transtorno Autístico/genética , Deleção Cromossômica , Cromossomos Humanos Par 16 , Deficiência Intelectual/genética , Anormalidades Múltiplas , Adolescente , Adulto , Criança , Pré-Escolar , Hibridização Genômica Comparativa , Análise Mutacional de DNA , Saúde da Família , Feminino , Testes Genéticos , Humanos , Lactente , Deficiências da Aprendizagem , Masculino , Distúrbios da Fala , Adulto Jovem
10.
Neurology ; 69(2): 218-9, 2007 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-17620557
11.
JBR-BTR ; 86(5): 268-71, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14651081

RESUMO

We present a case of cystic islet cell tumor of the pancreas in a 60-year old male with myotonic dystrophy. A cystic lesion was found with a thick peripheral rim, a few intralesional septae and a fluid-debris level on CT and MRI. Image characteristics are compared with the pathological findings. MRI demonstrated the internal architecture of the lesion more clearly.


Assuntos
Insulinoma/diagnóstico , Insulinoma/patologia , Distrofia Miotônica/complicações , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Humanos , Insulinoma/complicações , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Pâncreas/patologia , Neoplasias Pancreáticas/complicações , Tomografia Computadorizada por Raios X
12.
Acta Neurol Belg ; 103(2): 78-82, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12892000

RESUMO

In recent years, different research lines have examined the epileptogenic process in order to understand the different stages in this process, and with the hope that early recognition and intervention could prevent chronic epilepsy in patients with epileptic seizures. In animals, acquired epilepsy is studied most commonly with kindling models, status epilepticus models and traumatic brain injury models. Molecular genetic studies substantially help to understand age-specific channel and receptor abnormalities. Major progress has been made in recent years and we are now waiting for the first large scale multi-center clinical trials that test the possible anti-epileptogenic properties of anti-epileptic drugs or other compounds in well defined patient groups. In clinical practice, a structured diagnostic work-up in all patients with recurrent seizures is a first and necessary step in the recognition of patients at risk for developing chronic and refractory epilepsy.


Assuntos
Epilepsia/etiologia , Epilepsia/fisiopatologia , Animais , Anticonvulsivantes/farmacologia , Epilepsia/tratamento farmacológico , Humanos , Excitação Neurológica , Modelos Animais
13.
JBR-BTR ; 86(2): 74-6, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12839419

RESUMO

The authors report on a case of midgut volvulus in a 27-year-old man who presented with bilious vomiting and acute abdominal pain. US demonstrated a reversal of the normal relationship between the superior mesenteric artery (SMA) and superior mesenteric vein (SMV). A clockwise whirlpool sign, diagnostic for midgut volvulus, was not visualised. In a further assessment, upper gastrointestinal series demonstrated obstruction in the second part of the duodenum highly suspicious of Ladd's bands. Malpositioning of bowel structures, as already suggested by the reversal of the SMA and SMV on ultrasound, and a distinctive whirl pattern due to the bowel wrapping around the SMA was demonstrated on CT. Furthermore angiography revealed focal twisting of the SMA. US is the first imaging modality to perform in suspicion of midgut volvulus. When inconclusive, CT is in our opinion the next stage in the diagnostic work-up.


Assuntos
Angiografia , Obstrução Duodenal/diagnóstico por imagem , Volvo Intestinal/diagnóstico por imagem , Artéria Mesentérica Superior/anormalidades , Veias Mesentéricas/anormalidades , Tomografia Computadorizada por Raios X , Abdome Agudo/diagnóstico por imagem , Abdome Agudo/etiologia , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Artéria Mesentérica Superior/diagnóstico por imagem , Oclusão Vascular Mesentérica/diagnóstico por imagem , Veias Mesentéricas/diagnóstico por imagem
14.
Eur Radiol ; 13 Suppl 4: L40-4, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15018164

RESUMO

Two cases of pseudotumoral peliosis hepatis are presented with emphasis on MRI findings. One patient had four individual lesions, the other had two. Image characteristics in both were: heterogeneic signal intensity on T1-weighted images (T1WI) with areas of high-, intermediate, and low signal intensity; heterogeneic signal intensity on T2WI with presence of numerous intralesional "cystic" hyperintense areas with a hypointense border. Signal intensities on T1WI were iso- to hypointense in one case and mild central hyperintensities were demonstrated in the other case, probably due to intra-lesional hemorrhage or diffuse accumulation of fresh clotting within the sinusoids. One case demonstrated early enhancement of the peripheral borders in the arterial phase, and both demonstrated enhancement in the portovenous and late phases. One case was studied with Gd-BOPTA and iron oxides and demonstrated enhancement with both products, suggestive for the presence of hepatocytes and Kupffer cells. This is the first report of the use of hepato-specific contrast agents in this entity. Spontaneous regression of the lesions was demonstrated on a follow-up MR examination in one case.


Assuntos
Granuloma de Células Plasmáticas/diagnóstico , Neoplasias Hepáticas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Peliose Hepática/diagnóstico , Idoso , Biópsia por Agulha , Diagnóstico Diferencial , Feminino , Seguimentos , Gadolínio DTPA , Humanos , Imuno-Histoquímica , Masculino , Medição de Risco , Sensibilidade e Especificidade
15.
Pediatr Res ; 50(5): 658-65, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11641463

RESUMO

Catalytic activity of oxidative phosphorylation complexes is maintained following separation by Blue Native polyacrylamide gel electrophoresis (BN-PAGE). In BN-PAGE gels, using histochemical staining methods, we have demonstrated enzymatic activity of the complexes I, II, IV, and V in heart and skeletal muscle, liver, and cultured skin fibroblasts. The combination of BN-PAGE and catalytic staining can be successfully applied for detection of complex deficiencies. Tissues from 18 patients with deficiency in the oxidative phosphorylation as detected by spectrophotometric assay were used (10 patients complex IV, three patients complex I, one patient complex II, one patient complex I+III, three patients complex I+IV). The gene defect was located in nuclear DNA in five patients and mitochondrial DNA in one patient. In samples from patients with a severe deficiency, almost complete absence of the corresponding enzyme band is observed after catalytic staining in the gel. In patients with known partial deficiency, a milder decrease of the corresponding enzyme band is demonstrated. The amount of protein in complexes I, V, and III can easily be evaluated in samples from heart and skeletal muscle after separation by BN-PAGE using silver or Coomassie staining. The protein amount in complex IV is difficult to visualize by silver staining but easier by the Coomassie technique. In samples from liver and cultured skin fibroblasts, evaluation of protein amount is more difficult due to high background staining. In these tissues, immunoblotting can be done after BN-PAGE and subsequent transfer to a nitrocellulose membrane.


Assuntos
Eletroforese em Gel de Poliacrilamida/métodos , Erros Inatos do Metabolismo/diagnóstico , Fosforilação Oxidativa , Adolescente , Adulto , Catálise , Núcleo Celular/genética , Células Cultivadas , Criança , DNA Mitocondrial/genética , Humanos , Recém-Nascido , Mitocôndrias Hepáticas/enzimologia , Mitocôndrias Musculares/enzimologia
16.
Arch Neurol ; 58(7): 1113-8, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11448301

RESUMO

OBJECTIVE: To report on the molecular identification of a novel heteroplasmic G-to-A transition at mitochondrial DNA position 3249 in transfer RNA(Leu) gene in a patient with a clinical phenotype resembling Kearns-Sayre syndrome. PATIENT AND METHODS: A 34-year-old patient had been suffering for more than 10 years from progressive visual failure, neurosensorial hearing loss, exercise intolerance, muscle weakness, paresthesia in the lower limbs, and difficulties swallowing. Clinical examination revealed generalized muscle wasting, ptosis, external ophthalmoplegia, and ataxia. Ophthalmologic examination showed dystrophic features in the cornea and retina. In skeletal muscle, morphologic and biochemical studies of the respiratory chain complexes were performed. Polymerase chain reaction, single-strand conformation polymorphism, and direct sequencing were used to screen for mutations in the 22 mitochondrial transfer RNA genes. RESULTS: In skeletal muscle, a significantly decreased catalytic activity of complex I was detected by spectrophotometric analysis and numerous cytochrome c oxidase-negative ragged-red fibers were seen on morphologic examination. A G-to-A substitution 3249 (G3249A) mutation was found in the transfer RNA(Leu) gene of the patient and mutant mitochondrial DNA represented 85% of the total in skeletal muscle but only 45% in leukocytes. The mutation was shown to be present in a small fraction in leukocytes from the unaffected mother and to be absent in leukocytes from the healthy sister. CONCLUSIONS: A causal relationship between a heteroplasmic G3249A transfer RNA(Leu) mutation in a patient suffering from progressive external ophthalmoplegia, retinal dystrophy, ataxia, neurosensorial hearing loss, and muscle wasting is postulated. To our knowledge, the G3249A mutation has never previously been described and was not detected in control subjects.


Assuntos
Encéfalo/patologia , DNA Mitocondrial/genética , Síndrome de Kearns-Sayre/genética , Leucina/genética , Mutação Puntual , RNA/genética , Adulto , Atrofia , Humanos , Síndrome de Kearns-Sayre/enzimologia , Síndrome de Kearns-Sayre/patologia , Imageamento por Ressonância Magnética , Masculino , Mitocôndrias Musculares/enzimologia , Músculo Esquelético/patologia , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples
17.
Acta Neurol Belg ; 101(3): 171-6, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11817266

RESUMO

Topiramate (TPM) is a new anti-epileptic drug with proven efficacy against partial seizures in adults. Its use in children is less well documented. In a retrospective study, 41 patients with intractable childhood epilepsy were treated with TPM as add-on therapy for an average period of 15 months. They were classified according to seizure type and etiology. The dose was titrated for effect and ranged between 2 and 24 mg/kg/d. Of the 41 patients being treated, six became seizure free, ten had a seizure reduction of more than 75% and eight a seizure reduction of between 50 and 75%. The most remarkable effect was seen in seven patients with West syndrome. Of these, four patients became seizure free and one had more than 75% seizure reduction. Adverse effects including sedation, fatigue, difficulties with verbal expression and anorexia were noted in 15 patients. None of these effects were important enough to interrupt treatment. We conclude that TPM as adjunctive therapy is a promising drug in children with intractable epilepsy, especially in the patients with West syndrome.


Assuntos
Anticonvulsivantes/administração & dosagem , Frutose/administração & dosagem , Espasmos Infantis/tratamento farmacológico , Espasmos Infantis/fisiopatologia , Adolescente , Adulto , Anticonvulsivantes/efeitos adversos , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Eletroencefalografia/efeitos dos fármacos , Feminino , Frutose/efeitos adversos , Frutose/análogos & derivados , Humanos , Lactente , Masculino , Estudos Retrospectivos , Topiramato , Resultado do Tratamento
18.
Eur J Paediatr Neurol ; 4(5): 235-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11030070

RESUMO

A family with a hereditary peripheral neuropathy is presented. Pedigree analysis suggested X-linked dominant mode of inheritance. The index patient became symptomatic at the age of 12 years. Clinical examination at 14 years revealed footdrop on the left, bilateral pes cavus, slight atrophy of thenar eminences, decreased muscle strength in both legs and brisk deep tendon reflexes. Electrophysiological studies were compatible with an axonal neuropathy. A novel point mutation located in codon 126 of the connexin32 gene, substituting a histidine for a tyrosine, was found in the index patient, in the mother, in two sisters and in a brother. The mother and the eldest sister had pes cavus bilaterally although they were asymptomatic. The younger brother and sister showed no signs of the disease.


Assuntos
Doença de Charcot-Marie-Tooth/genética , Conexinas/genética , Ligação Genética/genética , Mutação Puntual , Cromossomo X , Adolescente , Doença de Charcot-Marie-Tooth/fisiopatologia , Criança , Feminino , Genótipo , Humanos , Masculino , Linhagem , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Polineuropatias/fisiopatologia , Proteína beta-1 de Junções Comunicantes
19.
Acta Chir Belg ; 99(4): 171-3, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10499388

RESUMO

A 47-year-old female with fibromuscular dysplasia of both external iliac arteries was treated by percutaneous balloon catheter angioplasty. The immediate result was unsatisfactory. On discharge from hospital, the patient was only able to walk one kilometer, and had reduced ankle:arm blood pressure indices. Conservative treatment with anticoagulants for three months, followed by ticlopidine, and exercise for six months led to complete recovery.


Assuntos
Displasia Fibromuscular/terapia , Artéria Ilíaca/patologia , Angioplastia com Balão , Tornozelo/irrigação sanguínea , Anticoagulantes/uso terapêutico , Braço/irrigação sanguínea , Pressão Sanguínea , Terapia por Exercício , Feminino , Displasia Fibromuscular/tratamento farmacológico , Humanos , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Ticlopidina/uso terapêutico , Resultado do Tratamento
20.
Acta Chir Belg ; 98(6): 269-72, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9922817

RESUMO

A 59-year-old male developed a severe adult respiratory distress syndrome following a right pneumonectomy for pulmonary cancer. Extracorporeal membrane oxygenation for 11 days was life-saving. The operation was considered curative, but the patient died nine months later with multiple metastases. The pathogenesis and treatment for postpneumonectomy pulmonary oedema and an explanation for rapid dissemination of the cancer are stated.


Assuntos
Adenocarcinoma/cirurgia , Oxigenação por Membrana Extracorpórea , Neoplasias Pulmonares/cirurgia , Pneumonectomia , Complicações Pós-Operatórias , Edema Pulmonar/terapia , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade , Edema Pulmonar/etiologia , Síndrome do Desconforto Respiratório/etiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...