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1.
Clin Microbiol Infect ; 26(5): 613-618, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31655215

RESUMO

OBJECTIVES: The United States Food & Drug Administration released an advisory in 2016 that fluoroquinolones be relegated to second-line agents for uncomplicated urinary tract infections (UTIs) given reports of rare but serious side effects; similar warnings have followed from Health Canada and the European Medicines Agency. The objective was to determine whether alternative non-fluoroquinolone agents are as effective as fluoroquinolones in the treatment of UTIs. METHODS: We conducted a retrospective population-based cohort study using administrative health data from six Canadian provinces. We identified women (n = 1 585 997) receiving antibiotic treatment for episodes of uncomplicated UTIs (n = 2 857 243) between January 1 2005 and December 31 2015. Clinical outcomes within 30 days from the initial antibiotic dispensation were compared among patients treated with a fluoroquinolone versus non-fluoroquinolone agents. High-dimensional propensity score adjustments were used to ensure comparable treatment groups and to minimize residual confounding. RESULTS: Fluoroquinolone use for UTI declined over the study period in five of six Canadian provinces and accounted for 22.3-48.5% of treatments overall. The pooled effect across the provinces indicated that fluoroquinolones were associated with fewer return outpatient visits (OR 0.89, 95%CI 0.87-0.92), emergency department visits (OR 0.74, 95%CI 0.61-0.89), hospitalizations (OR 0.83, 95%CI 0.77-0.88), and repeat antibiotic dispensations (OR 0.77, 95%CI 0.75-0.80) within 30 days. CONCLUSIONS: Fluoroquinolones are associated with improved clinical outcomes among women with uncomplicated UTIs. This benefit must be weighed against the risk of fluoroquinolone resistance and rare but serious fluoroquinolone side effects when selecting first-line treatment for these patients.


Assuntos
Antibacterianos/uso terapêutico , Fluoroquinolonas/uso terapêutico , Infecções Urinárias/tratamento farmacológico , Antibacterianos/efeitos adversos , Canadá/epidemiologia , Feminino , Fluoroquinolonas/efeitos adversos , Humanos , Retratamento/estatística & dados numéricos , Estudos Retrospectivos , Resultado do Tratamento , Infecções Urinárias/epidemiologia
2.
Pediatr Nephrol ; 34(9): 1565-1574, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31049718

RESUMO

BACKGROUND: The validity of pediatric estimated glomerular filtration rate equations (eGFRs) in early stages of CKD including hyperfiltration is unknown. The purpose of this study was to develop an eGFR equation for adolescents with obesity and type 2 diabetes (T2D). METHODS: eGFRs were developed from iohexol-derived GFRs (iGFRs) in 26 overweight/obese (BMI > 85th percentile) youth and 100 with T2D from the iCARE (Improving renal Complications in Adolescents with T2D through REsearch) cohort. Twenty percent of the cohort was withheld as a validation dataset. Linear regression analyses were used to develop the best formula based on body size, sex, creatinine, urea, ± cystatin C. Comparable validity of commonly used eGFR equations was assessed. RESULTS: Mean age 15.4 + 2.4 years, BMI Z-score 2.5 + 1.2, 61% female, and mean iGFR 129.0 + 27.7 ml/min/ 1.73 m2. The best adjusted eGFR formula (ml/min/1.73 m2) was 50.7 × BSA0.816 × (height (cm)/creatinine)0.405 × 0.8994 if sex = female | 1 otherwise. It resulted in 53.8% of eGFRs within 10% of measured iGFR and 96.2% within 30%. Bland-Altman 95% limits of agreement in the external dataset were - 37.6 to 45.5 ml/min/1.73m2 (bias = 3.96), and the correlation was 0.62. This equation performed better than all previously published creatinine-based eGFRs. cystatin C did not significantly improve results; however, some other cystatin C formulas also performed well. CONCLUSIONS: The iCARE equation provides a more accurate creatinine-based eGFR in obese youth with and without T2D. Further studies are warranted to evaluate within-subject variability and applicability to lower GFRs and other populations.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Taxa de Filtração Glomerular/fisiologia , Modelos Biológicos , Obesidade/complicações , Insuficiência Renal Crônica/diagnóstico , Adolescente , Idade de Início , Creatinina/sangue , Estudos Transversais , Cistatina C/sangue , Conjuntos de Dados como Assunto , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Iohexol/administração & dosagem , Iohexol/farmacocinética , Masculino , Obesidade/sangue , Obesidade/fisiopatologia , Eliminação Renal/fisiologia , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/fisiopatologia , Ureia/sangue
3.
Int J Obes (Lond) ; 39(7): 1070-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25869598

RESUMO

OBJECTIVES: The optimal screening measures for obesity in children remain controversial. Our study aimed to determine the anthropometric measurement at age 10 years that most strongly predicts the incidence of cardio-metabolic risk factors at age 13 years. SUBJECTS/METHODS: This was a prospective cohort study of a population-based cohort of 438 children followed between age 7 and 13 years of age. The main exposure variables were adiposity at age 10 years determined from body mass index (BMI) Z-score, waist circumference (WC) Z-score, waist-to-hip ratio and waist-to-height ratio. Outcome measures included systolic (SBP) and diastolic blood pressure (DBP), fasting high-density (HDL-c) and low-density lipoprotein cholesterol (LDL-c), triglycerides, insulin and glucose (homeostasis model of assessment, HOMA), and the presence of metabolic syndrome (MetS). RESULTS: WC Z-score at age 10 years was a stronger predictor of SBP (ß 0.21, R(2) 0.38, P<0.001 vs ß 0.30, R(2) 0.20, P<0.001) and HOMA (ß 0.51, R(2) 0.25, P<0.001 vs 0.40, R(2) 0.19, P<0.001) at age 13 years compared with BMI Z-score. WC relative to height and hip was stronger predictors of cardio- metabolic risk than BMI Z-score or WC Z-score. The relative risk (RR) of incident MetS was greater for an elevated BMI Z-score than for an elevated WC (girls: RR 2.52, 95% confidence interval (CI): 1.46-4.34 vs RR 1.56, 95% CI 1.18-2.07) and (boys: RR 2.86, 95% CI 1.79-4.62 vs RR 2.09, 95% CI 1.59-2.77). CONCLUSIONS: WC was a better predictor of SBP and HOMA compared with BMI or WC expressed relative to height or hip circumference. BMI was associated with higher odds of MetS compared with WC. Thus, BMI and WC may each be clinically relevant markers of different cardio-metabolic risk factors, and important in informing obesity-related prevention and treatment strategies.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Síndrome Metabólica/prevenção & controle , Obesidade/prevenção & controle , Pressão Sanguínea , Estatura , Índice de Massa Corporal , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Criança , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Humanos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/etiologia , Obesidade/sangue , Obesidade/complicações , Obesidade/epidemiologia , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco , Distribuição por Sexo , Triglicerídeos/sangue , Circunferência da Cintura , Relação Cintura-Quadril
4.
Early Child Dev Care ; 185(2): 291-316, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25632172

RESUMO

In the first longitudinal, population-based study of full-day kindergarten (FDK) outcomes beyond primary school in Canada, we used linked administrative data to follow 15 kindergarten cohorts (n ranging from 112 to 736) up to grade 9. Provincial assessments conducted in grades 3, 7, and 8 and course marks and credits earned in grade 9 were compared between FDK and half-day kindergarten (HDK) students in both targeted and universal FDK programmes. Propensity score matched cohort and stepped-wedge designs allowed for stronger causal inferences than previous research on FDK. We found limited long-term benefits of FDK, specific to the type of programme, outcomes examined, and subpopulations. FDK programmes targeted at low-income areas showed long-term improvements in numeracy for lower income girls. Our results suggest that expectations for wide-ranging long-term academic benefits of FDK are unwarranted.

5.
Nanoscale ; 7(5): 1934-43, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25530122

RESUMO

Anisotropic gold nanoparticles and in particular with shapes exhibiting tips are known to present an extremely strong localized electromagnetic field. This field is mostly located at the top of the tips and can be used in various optical applications. Moreover, as a consequence of their anisotropy, they present two plasmon resonance bands corresponding to the transverse and longitudinal resonance modes. Tuning the aspect ratio it becomes possible to display SPR bands near the near infrared region. This was particularly investigated in the case of nanorods and also for bipyramids. In this paper we report a high yield synthesis approach that allows one to precisely control the aspect ratio of bipyramids and to elongate the structure until they adopt a javelin-like aspect. We were able to prepare nano-javelins with surface plasmon resonances up to 1850 nm, opening important perspectives in terms of optical applications in the NIR and IR regions. The synthetic methods are fully reported and the optical properties were correlated with the theoretical approach, taking into consideration not only the aspect ratio but also the truncation of the nano-objects.

6.
Psychol Med ; 45(3): 495-504, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25032807

RESUMO

BACKGROUND: The association between physical disorders and suicide remains unclear. The aim of this study was to examine the relationship between physical disorders and suicide after accounting for the effects of mental disorders. METHOD: Individuals who died by suicide (n = 2100) between 1996 and 2009 were matched 3:1 by balancing score to general population controls (n = 6300). Multivariate conditional logistic regression compared the two groups across physician-diagnosed physical disorders [asthma, chronic obstructive pulmonary disease (COPD), ischemic heart disease, hypertension, diabetes, cancer, multiple sclerosis and inflammatory bowel disease], adjusting for mental disorders and co-morbidity. Secondary analyses examined the risk of suicide according to time since first diagnosis of each physical disorder (1-90, 91-364, ⩾ 365 days). Similar analyses also compared individuals with suicide attempts (n = 8641) to matched controls (n = 25 923). RESULTS: Cancer was associated with increased risk of suicide [adjusted odds ratio (AOR) 1.40, 95% confidence interval (CI) 1.03-1.91, p < 0.05] even after adjusting for all mental disorders. The risk of suicide with cancer was particularly high in the first 90 days after initial diagnosis (AOR 4.10, 95% CI 1.71-9.82, p < 0.01) and decreased to non-significance after 1 year. Women with respiratory diseases had elevated risk of suicide whereas men did not. COPD, hypertension and diabetes were each associated with increased odds of suicide attempts in adjusted models (AORs ranged from 1.20 to 1.73). CONCLUSIONS: People diagnosed with cancer are at increased risk of suicide, especially in the 3 months following initial diagnosis. Increased support and psychiatric involvement should be considered for the first year after cancer diagnosis.


Assuntos
Transtornos Mentais/epidemiologia , Neoplasias/psicologia , Tentativa de Suicídio/estatística & dados numéricos , Adulto , Idoso , Canadá , Comorbidade , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Fatores de Risco
7.
Artigo em Inglês | MEDLINE | ID: mdl-24125375

RESUMO

A slider is pulled by means of a flexible link on a flat solid surface which exhibits anisotropic frictional properties. The resulting trajectory of the slider is assessed experimentally. First, we check that the experimental results are in excellent agreement with a theoretical description of the problem based on an expression of the frictional forces. Second, we point out that the trajectory of the slider can be recovered by the use of a "maximum of energy release rate" criterion which is generally used to predict the path of a fracture even if the validity of the principle is difficult to verify in the latter complex systems.

8.
Hum Mol Genet ; 11(14): 1637-45, 2002 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12075008

RESUMO

Glycogenosis type II (GSD II) is a lysosomal disorder affecting skeletal and cardiac muscle. In the infantile form of the disease, patients display cardiac impairment, which is fatal before 2 years of life. Patients with juvenile or adult forms can present diaphragm involvement leading to respiratory failure. The enzymatic defect in GSD II results from mutations in the acid alpha-glucosidase (GAA) gene, which encodes a 76 kDa protein involved in intralysosomal glycogen hydrolysis. We previously reported the use of an adenovirus vector expressing GAA (AdGAA) for the transduction of myoblasts and myotubes cultures from GSD II patients. Transduced cells secreted GAA in the medium, and GAA was internalized by receptor-mediated capture, allowing glycogen hydrolysis in untransduced cells. In this study, using a GSD II mouse model, we evaluated the feasibility of GSD II gene therapy using muscle as a secretary organ. Adenovirus vector encoding AdGAA was injected in the gastrocnemius of neonates. We detected a strong expression of GAA in the injected muscle, secretion into plasma, and uptake by peripheral skeletal muscle and the heart. Moreover, glycogen content was decreased in these tissues. Electron microscopy demonstrated the disappearance of destruction foci, normally present in untreated mice. We thus demonstrate for the first time that muscle can be considered as a safe and easily accessible organ for GSD II gene therapy.


Assuntos
Terapia Genética/métodos , Glucana 1,4-alfa-Glucosidase/genética , Glucana 1,4-alfa-Glucosidase/metabolismo , Doença de Depósito de Glicogênio Tipo II/genética , Doença de Depósito de Glicogênio Tipo II/terapia , Músculo Esquelético/metabolismo , Adenoviridae/genética , Animais , Vetores Genéticos/farmacologia , Glicogênio/metabolismo , Injeções Intramusculares , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Camundongos , Camundongos Knockout , Microscopia Eletrônica , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , alfa-Glucosidases
9.
Ann Neurol ; 48(5): 745-57, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11079538

RESUMO

Multi-minicore disease (MmD) is a congenital myopathy morphologically defined by the presence of multiple small zones of sarcomeric disorganization and lack of oxidative activity ("minicores") in muscle fibers. The dinical expression of MmD is considered to be greatly variable, and the morphological lesions are nonspecific; therefore, its boundaries are poorly defined, and its molecular bases are not known. To better define the phenotypic characteristics of MmD, we analyzed a large series of 38 patients with multiple minicores in muscle fibers in the absence of any other potential cause. According to clinical features, 4 subgroups were identified. Most patients (30 cases) shared a common highly consistent phenotype marked by the axial predominance of muscle weakness and a high occurrence of severe respiratory insufficiency and scoliosis ("classical" form). Other forms were characterized by pharyngolaryngeal involvement and total lack of head control (2 cases), antenatal onset with arthrogryposis (3 cases), and slowly progressive weakness with marked hand amyotrophy (3 cases). Type 1 fiber predominance and hypotrophy as well as centrally located nuclei were found in every subgroup. MmD is thus phenotypically heterogeneous, but a typical recognizable phenotype does exist. This phenotype classification should be helpful when undertaking research into the molecular defects that cause MmD.


Assuntos
Músculos/patologia , Doenças Musculares/genética , Doenças Musculares/patologia , Biópsia , Feminino , Humanos , Masculino , Fenótipo , Estudos Retrospectivos
10.
Pediatr Res ; 48(2): 143-50, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10926287

RESUMO

Most mitochondrial DNA (mtDNA) alterations associated with human disorders are heteroplasmic, i.e. mutant mtDNA molecules coexist with normal ones within the cell. We addressed the possibility of intermitochondrial exchanges through histologic analyses of cybrid clones with increasing proportion of the MELAS (A3243G) mtDNA transfer RNA point mutation. MtDNA-dependent cytochrome c oxidase activity and protein composition as well as mitochondrial membrane potential appeared heterogeneous in individual cells from clonal heteroplasmic cell populations on the basis of confocal and electron microscopy. The number of defective cells increased with increasing mutation load. We conclude that in the presence of a heteroplasmic mtDNA mutation in the cell type that we studied, intermitochondrial molecular exchanges cannot provide an efficient even distribution of the complementing molecules such as wild-type mtDNA, transfer RNA, or protein. Mitochondria in these heteroplasmic cells cannot, therefore, be considered a single functional unit.


Assuntos
DNA Mitocondrial/genética , Síndrome MELAS/genética , Mitocôndrias/fisiologia , Mutação Puntual , RNA de Transferência de Leucina/genética , Fusão Celular , Células Cultivadas , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Humanos , Células Híbridas , Membranas Intracelulares/fisiologia , Potenciais da Membrana , Mitocôndrias/enzimologia , Mitocôndrias/genética , Músculo Esquelético/patologia , Osteossarcoma , Succinato Desidrogenase/metabolismo , Células Tumorais Cultivadas
11.
Rev Neurol (Paris) ; 156(5): 497-504, 2000 May.
Artigo em Francês | MEDLINE | ID: mdl-10844369

RESUMO

Two familial cases of a myopathy remarkable by the presence of a granulo-filamentar, electron dense material were reported in 1978. In a second step, in 1988, it was demonstrated that this material contained an abnormally-phosphorylated desmin. During the last twenty years, the occurrence of new cases in this family confirmed the autosomal dominant inheritance of the disease, and made it potentially informative for molecular genetics studies. This allowed first to map the disease on chromosome11q21-23, and afterwards to identify a mutation within a gene coding for a chaperone protein, alphaBcrystallin. An extensive clinical, pathological and genetic study of this princeps family is herein reported in detail. First, it showed the possible detection of histopathological changes in presymptomatic patients. Second, it allowed to demonstrate the simultaneous occurrence of both alphaBcrystallin and desmin in the granulo-filamentar aggregates. Third, this study provided a precise knowledge of the evolution rate of the disease. The analysis of similar observations reported in the literature clearly shows the clinical, pathological and genetic heterogeneity of this new neuro-muscular disorder.


Assuntos
Citoesqueleto de Actina/genética , Cristalinas/genética , Grânulos Citoplasmáticos/genética , Desmina/genética , Miopatias Congênitas Estruturais/genética , Citoesqueleto de Actina/patologia , Adulto , Idoso , Biópsia , Grânulos Citoplasmáticos/patologia , Feminino , Seguimentos , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Miopatias Congênitas Estruturais/diagnóstico , Miopatias Congênitas Estruturais/patologia , Linhagem
12.
Mem Cognit ; 28(1): 143-53, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10714145

RESUMO

The effect of exposure to print on the efficiency of phonological and orthographic word recognition processes was examined by comparing two groups of university students having similar reading comprehension scores but different levels of exposure to print. Participants with a high level of exposure to print were faster and more accurate in naming pseudowords, in choosing the correct member of a homophone pair, and in making lexical decisions when nonwords were pseudohomophones. In the lexical decision task, low-print-exposure participants were more sensitive to the frequency of the orthographic patterns in the stimuli. The results of a form priming task demonstrated that high-print-exposure participants more quickly and strongly activated the orthographic representations of common words and subsequently more strongly activated the corresponding phonological representations. Even among successful students, differences in exposure to print produce large differences in the efficiency of both orthographic and phonological word recognition processes.


Assuntos
Rememoração Mental , Fonética , Leitura , Aprendizagem Verbal , Adulto , Tomada de Decisões , Feminino , Humanos , Masculino , Aprendizagem por Associação de Pares , Psicolinguística , Tempo de Reação , Semântica
13.
Ann Neurol ; 46(4): 559-67, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10514092

RESUMO

Myasthenia gravis (MG) is an autoimmune disease targeting the skeletal muscle acetylcholine receptor. We have previously demonstrated a selection bias of CD4+ T cells expressing the Vbeta5.1 T-cell receptor gene in the thymus of HLA-DR3 patients with MG. To evaluate the pathogenicity of these cells, severe combined immunodeficiency mice engrafted with MG thymic lymphocytes were treated with anti-Vbeta5.1 antibody. Signs of pathogenicity (eg, acetylcholine receptor loss and complement deposits at the muscle end plates of chimeric mice) were prevented in anti-Vbeta5.1-treated severe combined immunodeficiency chimeras. Pathogenicity was mediated by autoantibodies against acetylcholine receptor. Thymic cells depleted of Vbeta5.1-positive cells in vitro before cell transfer were nonpathogenic, indicating that Vbeta5.1-positive cells are involved in the production of pathogenic autoantibodies. Acetylcholine receptor loss was prevented by Vbeta5.1 targeting in HLA-DR3 patients only, demonstrating specificity for HLA-DR3-peptide complexes. The action of the anti-Vbeta5.1 antibody involved both the in vivo depletion of Vbeta5.1-expressing cells and an increase in the interferon-gamma/interleukin-4 ratio, pointing to an immune deviation-based mechanism. This demonstration that a selective and specific T-helper cell population is involved in controlling pathogenic autoantibodies in MG holds promise for the treatment of MG.


Assuntos
Autoimunidade/imunologia , Placa Motora/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Adolescente , Adulto , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos SCID , Receptores Colinérgicos/imunologia
14.
Neuromuscul Disord ; 9(8): 580-6, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10619716

RESUMO

We report the case of a 28 year-old woman with left scapuloperoneal syndrome since the age of 24. The course was slowly progressive and diffuse weakness was observed 4 years later. Serum creatine kinase levels were moderately elevated (x3 normal value) and EMG showed mixed neurogenic and myogenic patterns. Muscle biopsy showed type I predominance and numerous reducing bodies in muscle fibers. Reducing bodies were strongly immunoreactive with antibodies to dystrophin, alpha-sarcoglycan, vimentin and ubiquitin. Desmin immunoreactivity was increased at the periphery of some reducing bodies but alphaB crystallin, alpha actinin, titin and nebulin were negative. Western blot analysis showed an increase in dystrophin, vimentin and desmin expression. Ultrastructurally, reducing bodies were composed of tubulofilamentous material, 17 nm in diameter, and immunoreactive with anti-Dys 2 antibody. Granulofilamentous material, immunoreactive with anti-desmin antibody was observed at the periphery of some reducing bodies. This report further highlights the proteinic composition of reducing bodies and shows that late onset reducing body myopathy may occur.


Assuntos
Doenças Musculares/congênito , Doenças Musculares/epidemiologia , Adulto , Idade de Início , Biópsia , Desmina/metabolismo , Distrofina/metabolismo , Feminino , Histocitoquímica , Humanos , Immunoblotting , Imuno-Histoquímica , Microscopia Eletrônica , Microscopia Imunoeletrônica , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Doenças Musculares/patologia , Vimentina/metabolismo
15.
Neuromuscul Disord ; 8(7): 459-66, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9829275

RESUMO

A distal myopathy characterised by an autosomal dominant inheritance, with clinical onset around the age of 60, early involvement of posterior leg and thigh muscles, and normal or slightly-elevated creatine kinase levels was identified in three members of a French kindred. Tibialis anterior muscles were involved only in the most severely-affected sibling. Histological features included large multiple nonrimmed vacuolation and focal intrasarcoplasmic masses which immunoreacted with the anti-desmin antibody. Cytoplasmic and intranuclear tubulofilamentous inclusions were observed by electron microscopy. The condition of this familial syndrome is discussed in relation to previously-identified autosomal dominant distal myopathies and inclusion body myopathies.


Assuntos
Genes Dominantes/genética , Doenças Musculares/genética , Idade de Início , Feminino , Humanos , Perna (Membro) , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Músculos/patologia , Músculos/ultraestrutura , Doenças Musculares/patologia , Linhagem
16.
Am J Hum Genet ; 63(4): 967-75, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9758617

RESUMO

Congenital myasthenic syndrome (CMS) with end-plate acetylcholinesterase (AChE) deficiency is a rare autosomal recessive disease, recently classified as CMS type Ic (CMS-Ic). It is characterized by onset in childhood, generalized weakness increased by exertion, refractoriness to anticholinesterase drugs, and morphological abnormalities of the neuromuscular junctions (NMJs). The collagen-tailed form of AChE, which is normally concentrated at NMJs, is composed of catalytic tetramers associated with a specific collagen, COLQ. In CMS-Ic patients, these collagen-tailed forms are often absent. We studied a large family comprising 11 siblings, 6 of whom are affected by a mild form of CMS-Ic. The muscles of the patients contained collagen-tailed AChE. We first excluded the ACHE gene (7q22) as potential culprit, by linkage analysis; then we mapped COLQ to chromosome 3p24.2. By analyzing 3p24.2 markers located close to the gene, we found that the six affected patients were homozygous for an interval of 14 cM between D3S1597 and D3S2338. We determined the COLQ coding sequence and found that the patients present a homozygous missense mutation, Y431S, in the conserved C-terminal domain of COLQ. This mutation is thought to disturb the attachment of collagen-tailed AChE to the NMJ, thus constituting the first genetic defect causing CMS-Ic.


Assuntos
Acetilcolinesterase/deficiência , Acetilcolinesterase/genética , Colágeno , Proteínas Musculares , Mutação , Doenças Neuromusculares/genética , Adulto , Sequência de Aminoácidos , Mapeamento Cromossômico , Cromossomos Humanos Par 3 , Feminino , Humanos , Escore Lod , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Junção Neuromuscular/ultraestrutura , Linhagem , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Síndrome
17.
Nat Genet ; 20(1): 92-5, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9731540

RESUMO

Desmin-related myopathies (DRM) are inherited neuromuscular disorders characterized by adult onset and delayed accumulation of aggregates of desmin, a protein belonging to the type III intermediate filament family, in the sarcoplasma of skeletal and cardiac muscles. In this paper, we have mapped the locus for DRM in a large French pedigree to a 26-cM interval in chromosome 11q21-23. This region contains the alphaB-crystallin gene (CRYAB), a candidate gene encoding a 20-kD protein that is abundant in lens and is also present in a number of non-ocular tissues, including cardiac and skeletal muscle. AlphaB-crystallin is a member of the small heat shock protein (shsp) family and possesses molecular chaperone activity. We identified an R120G missense mutation in CRYAB that co-segregates with the disease phenotype in this family. Muscle cell lines transfected with the mutant CRYAB cDNA showed intracellular aggregates that contain both desmin and alphaB-crystallin as observed in muscle fibers from DRM patients. These results are the first to identify a defect in a molecular chaperone as a cause for an inherited human muscle disorder.


Assuntos
Cristalinas/genética , Cristalinas/metabolismo , Desmina/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Doenças Musculares/genética , Mutação , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Cricetinae , Cristalinas/ultraestrutura , Desmina/ultraestrutura , Feminino , Marcadores Genéticos , Proteínas de Choque Térmico/ultraestrutura , Humanos , Escore Lod , Masculino , Microscopia Imunoeletrônica , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Chaperonas Moleculares/ultraestrutura , Dados de Sequência Molecular , Músculo Esquelético/metabolismo , Músculo Esquelético/ultraestrutura , Doenças Musculares/metabolismo , Linhagem , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
18.
Neuromuscul Disord ; 8(2): 119-25, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9608566

RESUMO

We investigated two Japanese siblings presenting with oculopharyngodistal myopathy, whose healthy parents were consanguineous. To clarify their disease characteristics, we compared them with four patients with distal myopathy with rimmed vacuoles linked to chromosome 9p1-q1, and 36 patients with oculopharyngeal muscular dystrophy linked to 14q11.2-q13. The first symptom in the patients with autosomal recessive oculopharyngodistal myopathy was weakness of the tibialis anterior muscle. Their biceps muscles showed initial and advanced myogenic changes, with rimmed vacuoles in 3% and 6% of the muscle fibers, respectively. In contrast, patients with distal myopathy with rimmed vacuoles revealed many rimmed vacuoles, on average in 20% of the fibers, and their oculopharyngeal muscles were spared. None of the patients with oculopharyngeal muscular dystrophy showed distal dominant weakness and the occurrence of rimmed vacuoles was rare. Ultrastructural studies in groups of autosomal recessive oculopharyngodistal myopathy and distal myopathy with rimmed vacuoles disclosed a collection of cytoplasmic filaments of 16-18 nm, but oculopharyngeal muscular dystrophy-specific intranuclear inclusions of 8.5 nm were not found. Thus, the phenotype of autosomal recessive oculopharyngodistal myopathy is distinct from distal myopathy with rimmed vacuoles and oculopharyngeal muscular dystrophy, but shares some ultrastructural characteristics with distal myopathy with rimmed vacuoles and hereditary inclusion body myopathy.


Assuntos
Genes Recessivos , Doenças Musculares/genética , Músculos Oculomotores/ultraestrutura , Músculos Faríngeos/ultraestrutura , Vacúolos/ultraestrutura , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 8 , Diagnóstico Diferencial , Ligação Genética , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Doenças Musculares/patologia , Linhagem
19.
Neuromuscul Disord ; 7 Suppl 1: S41-9, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9392015

RESUMO

Oculopharyngeal muscular dystrophy (OPMD) in the European population has been frequently diagnosed, but except for one black family, the occurrence in other ethnic groups is uncertain. We identified two unrelated OPMD Japanese families, including 34 affected individuals. Major clinical manifestations were bilateral ptosis and dysphagia starting after age 40. Histologic studies of limb muscles revealed mild myogenic changes, occasional rimmed vacuoles, and small angulated fibers. By contrast, cricopharyngeal muscle showed a marked loss of fibers and massive proliferation of connective tissue. Intranuclear tubulofilamentous inclusions (ITFI) of 8.5 nm outer diameter were observed in 2-5% of the nuclei in four different biopsied muscles. One patient with recurrent aspirations underwent successful cricopharyngeal myotomy. Aerodynamic examination was useful to evaluate velopharyngeal closure function. Our investigations revealed that OPMD is a geographically widespread disorder, and ITFI may be the specific morphologic hallmark.


Assuntos
Distrofias Musculares/diagnóstico por imagem , Distrofias Musculares/genética , Músculos Oculomotores , Músculos Faríngeos , Biópsia , Blefaroptose/etiologia , Blefaroptose/genética , Saúde da Família , Feminino , Humanos , Japão , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Músculo Esquelético/ultraestrutura , Distrofias Musculares/patologia , Nariz/fisiologia , Linhagem , Faringe/diagnóstico por imagem , Faringe/patologia , Radiografia
20.
Neuromuscul Disord ; 7 Suppl 1: S63-9, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9392019

RESUMO

The study of muscle biopsies of 29 cases of oculopharyngeal muscular dystrophy (OPMD) showed the two main morphological features of this disease: rimmed vacuoles (in 26 cases) and intranuclear inclusions (in all cases). These inclusions are made of 8.5 nm tubular filaments and the areas occupied by them are lighter than the surrounded nucleoplasm. This can be seen by light microscopy, facilitating the detection of the tubulo-filamentous inclusions which can only be identified with certitude by electron microscopy. In a given ultrathin section the area occupied by these inclusions varied from 2% to 5% of the nuclei. The intranuclear inclusions are the morphological marker of OPMD and their finding in a muscle biopsy allows the exact diagnosis of this disease. The origin and biochemical nature of the intranuclear inclusions is unknown.


Assuntos
Distrofias Musculares/patologia , Músculos Oculomotores , Músculos Faríngeos , Adulto , Idoso , Biópsia , Humanos , Corpos de Inclusão/patologia , Corpos de Inclusão/ultraestrutura , Microscopia Eletrônica , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Vacúolos/patologia , Vacúolos/ultraestrutura
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