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1.
J Dairy Sci ; 103(2): 1110-1119, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31785881

RESUMO

The consumption of probiotic-enriched dairy products has been associated with many health benefits, including anti-hyperglycemic activity. The effect on health is dependent on the type of probiotic culture used and the dairy product consumed. This study evaluated the effect of different probiotic-enriched dairy matrices (Minas Frescal cheese, Prato cheese, and whey dairy beverage) containing Lactobacillus casei on in vitro and in vivo anti-hyperglycemic activity. For this purpose, in vitro anti-hyperglycemic activity was determined by the inhibition of α-glucosidase and α-amylase activities, and a human study was performed with healthy individuals (n = 15, consumption of bread as a control; bread + Minas Frescal cheese; bread + Prato cheese; bread + dairy beverage) to assess the effects of different probiotic foods on postprandial glycemia. In vitro data showed that Prato cheese presented the highest lipid (36.9 g/100 g) and protein (26.5 g/100 g) contents as well as the highest α-amylase (60.7%) and α-glucosidase (52.6%) inhibition. The consumption of Prato cheese resulted in a lesser increase in blood glucose level (13 mg/dL) compared with the consumption of bread alone (19 mg/dL), Minas Frescal cheese (20 mg/dL), and whey dairy beverage (30 mg/dL), with glycemic indices similar to that observed for the control. The present results demonstrated a good correlation between in vitro and in vivo data, in which the type of dairy matrix affects the anti-hyperglycemic activity. It is concluded that the consumption of probiotic Prato cheese can contribute to the reduction of postprandial glycemia in healthy individuals.


Assuntos
Glicemia/metabolismo , Laticínios , Hiperglicemia/prevenção & controle , Período Pós-Prandial , Probióticos , Adulto , Animais , Queijo , Feminino , Índice Glicêmico , Humanos , Hiperglicemia/sangue , Lacticaseibacillus casei/metabolismo , Masculino , Pessoa de Meia-Idade , Adulto Jovem
2.
J Helminthol ; 94: e4, 2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30362449

RESUMO

Dawestrema cycloancistrium is the main ectoparasite causing mortality in fingerlings of pirarucu (Arapaima gigas) in Amazonian aquaculture. Very little is known about the D. cycloancistrium reproductive index and appropriate methods of collecting eggs for investigation. This study aimed to determine the oviposition rate of D. cycloancistrium. To achieve this aim, two egg quantification methods were tested: the estimative method (ME) and the total counting method (MT). Compared with the MT, the ME overestimated the number of eggs counted, which were 2943.5 ± 2840.6 and 1041.5 ± 533 eggs, and the oviposition rate, which was 80.1 ± 58.7 and 31.4 ± 16.4 eggs/parasite/day, for ME and MT, respectively. These results show that for studies quantifying D. cycloancistrium eggs, the total eggs in the sample must be counted, as the estimates made using subsamples are not representative. Using the MT, the oviposition rate for D. cycloancistrium was determined to be 31.4 ± 16.4 eggs per adult parasite per day. The present study demonstrates the egg production capacity of a monogenean species parasite of A. gigas, providing basic biological data for D. cycloancistrium.


Assuntos
Contagem de Células/métodos , Doenças dos Peixes/parasitologia , Oviposição , Óvulo/citologia , Trematódeos/fisiologia , Infecções por Trematódeos/veterinária , Animais , Peixes , Cinética , Reprodução , Trematódeos/química , Infecções por Trematódeos/parasitologia
3.
J Water Health ; 14(3): 369-78, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27280604

RESUMO

Giardia and Cryptosporidium species are a serious problem if present in water supplies. The removal of these protozoans and the adaptation of existing protocols are essential for supplying drinking water to developing countries. Considering this, the aim of this study is to evaluate, on a bench level, the removal of Giardia spp. cysts and of Cryptosporidium spp. oocysts from water with high turbidity, using polyaluminium chloride as a coagulant. Filtration using mixed cellulose ester membranes, followed, or not, by purification through immunomagnetic separation (IMS) was used for detecting protozoans. By evaluating the adopted protocol, without using IMS, retrievals of 80% of cysts and 5% of oocysts were obtained, whereas by using IMS, recoveries of 31.5% of cysts and 5.75% of oocysts were reached. When analyzing the coagulant performance, a dosage of 65 mg L(-1) showed contamination from protozoans in all the samples of filtered water. A dosage of 25 mg L(-1) presented protozoans in 50% of the filtered water samples. The results showed an improved performance for the 25 mg L(-1) dosage; therefore, the control of coagulation and adaptation of detection protocols must be evaluated according to the features of raw water and availability of local resources.


Assuntos
Hidróxido de Alumínio/química , Cryptosporidium/isolamento & purificação , Água Potável/parasitologia , Giardia/isolamento & purificação , Purificação da Água/métodos , Filtração , Separação Imunomagnética , Oocistos , Abastecimento de Água/normas
4.
Genes Immun ; 13(2): 197-201, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21866115

RESUMO

Non-Hodgkin lymphoma (NHL) has been associated with immunological defects, chronic inflammatory and autoimmune conditions. Given the link between immune dysfunction and NHL, genetic variants in toll-like receptors (TLRs) have been regarded as potential predictive factors of susceptibility to NHL. Adequate anti-tumoral responses are known to depend on TLR9 function, such that the use of its synthetic ligand is being targeted as a therapeutic strategy. We investigated the association between the functional rs5743836 polymorphism in the TLR9 promoter and risk for B-cell NHL and its major subtypes in three independent case-control association studies from Portugal (1160 controls, 797 patients), Italy (468 controls, 494 patients) and the US (972 controls, 868 patients). We found that the rs5743836 polymorphism was significantly overtransmitted in both Portuguese (odds ratio (OR), 1.85; P=7.3E-9) and Italian (OR, 1.84; P=6.0E-5) and not in the US cohort of NHL patients. Moreover, the increased transcriptional activity of TLR9 in mononuclear cells from patients harboring rs5743836 further supports a functional effect of this polymorphism on NHL susceptibility in a population-dependent manner.


Assuntos
Linfoma não Hodgkin/genética , Polimorfismo Genético , Receptor Toll-Like 9/genética , Feminino , Genética Populacional , Humanos , Linfoma não Hodgkin/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco
5.
Water Res ; 208: 117870, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34823084

RESUMO

Household, or point-of-use (POU), water treatments are effective alternatives to provide safe drinking water in locations isolated from a water treatment and distribution network. The household slow sand filter (HSSF) is amongst the most effective and promising POU alternatives available today. Since the development of the patented biosand filter in the early 1990s, the HSSF has undergone a number of modifications and adaptations to improve its performance, making it easier to operate and increase users' acceptability. Consequently, several HSSF models are currently available, including those with alternative designs and constant operation, in addition to the patented ones. In this scenario, the present paper aims to provide a comprehensive overview from the earliest to the most recent publications on the HSSF design, operational parameters, removal mechanisms, efficiency, and field experiences. Based on a critical discussion, this paper will contribute to expanding the knowledge of HSSF in the peer-reviewed literature.


Assuntos
Filtração , Purificação da Água , Características da Família , Dióxido de Silício
7.
Neuroscience ; 147(4): 1022-33, 2007 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-17587501

RESUMO

Manipulation of the corticosteroid milieu by interfering with the mother-newborn relationship has received much attention because of its potential bearing on psychopathology later in life. In the present study, infant rats that were deprived of maternal contact between the 2nd and the 15th postnatal days (MS2-15) for 6 h/day were subjected to a systematic assessment of neurodevelopmental milestones between postnatal days 2 and 21. The analyses included measurements of physical growth and maturation and evaluation of neurological reflexes. Although some somatic milestones (e.g. eye opening) were anticipated, MS2-15 animals showed retardation in the acquisition of postural reflex, air righting and surface righting reflexes, and in the wire suspension test; the latter two abnormalities were only found in males. A gender effect was also observed in negative geotaxis, with retardation being observed in females but not males. To better understand the delay of neurological maturation in MS2-15 rats, we determined the levels of various monoamines in different regions of the brain stem, including the vestibular area, the substantia nigra, ventral tegmental area and dorsal raphe nuclei. In the vestibular region of MS2-15 rats the levels of 5-HT were reduced, while 5-HT turnover was increased. There was also a significant increase of the 5-HT turnover in MS2-15 animals in the raphe nuclei, mainly due to increased 5-hydroxyindoleacetic acid (5-HIAA) levels, and an increase of 3,4-dihydroxyphenylacetic acid (DOPAC) levels in the ventral tegmental area (VTA) of stressed females. No significant differences were found in the immunohistochemical sections for tyrosine and tryptophan hydroxylase in these regions of the brain stem. In conclusion, the present results show that postnatal stress induces signs of neurological pathology that may contribute to the genesis of behavioral abnormalities later in life.


Assuntos
Química Encefálica/fisiologia , Encéfalo , Privação Materna , Estresse Psicológico/patologia , Estresse Psicológico/fisiopatologia , Animais , Animais Recém-Nascidos , Comportamento Animal , Monoaminas Biogênicas/metabolismo , Encéfalo/anormalidades , Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Corticosterona/sangue , Período Crítico Psicológico , Embrião de Mamíferos , Feminino , Elevação dos Membros Posteriores/métodos , Masculino , Gravidez , Desempenho Psicomotor/fisiologia , Ratos , Ratos Wistar , Reflexo/fisiologia , Fatores Sexuais
8.
Braz J Biol ; 77(2): 367-371, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27579976

RESUMO

The present study evaluates the influence of anesthesia on the parasitic fauna of monogenea fish parasites, as its intensity and viability. Two experiments were conducted: Evaluation of an anesthetic method by sprinkling eugenol directly on gills and evaluation of monogenea motility and viability; Comparison of immersion and directly sprinkling on the gills with benzocaine and eugenol followed by evaluation on parasite intensity. The results suggest that the anesthetic sprinkling didn't interfere in the parasite motility, morphology and body surface integrity analyzed by fluorescence method. The monogenean intensity in the gills was lower in fish anesthetized by immersion method compared to the sprinkling method and the control group. This method of anesthesia can be used in parasitological studies.


Assuntos
Anestésicos/farmacologia , Benzocaína/farmacologia , Caraciformes/fisiologia , Caraciformes/parasitologia , Eugenol/farmacologia , Platelmintos/efeitos dos fármacos , Anestesia/veterinária , Animais , Brânquias/efeitos dos fármacos , Brânquias/parasitologia , Brânquias/fisiologia
9.
Genes Brain Behav ; 5 Suppl 2: 80-91, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16681803

RESUMO

Regulation of gene expression occurs at different levels, from DNA to protein, and through various mechanisms. One of them is modification of the chromatin structure, which is involved in the definition of transcriptional active and inactive regions of the chromosomes. These phenomena are associated with reversible chemical modifications of the genetic material rather than with variability within the DNA sequences inherited by the individual and are therefore called 'epigenetic' modifications. Ablation of the molecular players responsible for epigenetic modifications often gives rise to neurological and behavioral phenotypes in humans and in mouse models, suggesting a relevant function for chromatin remodeling in central nervous system function, particularly in the adaptive response of the brain to stimuli. We will discuss several human disorders that are due to altered epigenetic mechanisms, with special focus on Rett syndrome.


Assuntos
Montagem e Desmontagem da Cromatina/fisiologia , Regulação da Expressão Gênica/fisiologia , Proteína 2 de Ligação a Metil-CpG/metabolismo , Plasticidade Neuronal/genética , Síndrome de Rett/metabolismo , Adaptação Fisiológica/genética , Animais , Comportamento/fisiologia , Meio Ambiente , Epigênese Genética/fisiologia , Humanos , Proteína 2 de Ligação a Metil-CpG/genética , Camundongos , Camundongos Knockout , Plasticidade Neuronal/fisiologia , Síndrome de Rett/genética
10.
Neuroscience ; 313: 162-73, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26601773

RESUMO

A major pathological hallmark in several neurodegenerative disorders, like polyglutamine disorders (polyQ), including Machado-Joseph disease (MJD), is the formation of protein aggregates. MJD is caused by a CAG repeat expansion in the ATXN3 gene, resulting in an abnormal protein, which is prone to misfolding and forms cytoplasmic and nuclear aggregates within neurons, ultimately inducing neurodegeneration. Treatment of proteinopathies with drugs that up-regulate autophagy has shown promising results in models of polyQ diseases. Temsirolimus (CCI-779) inhibits the mammalian target of rapamycin (m-TOR), while lithium chloride (LiCl) acts by inhibiting inositol monophosphatase, both being able to induce autophagy. We have previously shown that chronic treatment with LiCl (10.4 mg/kg) had limited effects in a transgenic MJD mouse model. Also, others have shown that CCI-779 had mild positive effects in a different mouse model of the disease. It has been suggested that the combination of mTOR-dependent and -independent autophagy inducers could be a more effective therapeutic approach. To further explore this avenue toward therapy, we treated CMVMJD135 transgenic mice with a conjugation of CCI-779 and LiCl, both at concentrations known to induce autophagy and not to be toxic. Surprisingly, this combined treatment proved to be deleterious to both wild-type (wt) and transgenic animals, failing to rescue their neurological symptoms and actually exerting neurotoxic effects. These results highlight the possible dangers of manipulating autophagy in the nervous system and suggest that a better understanding of the potential disruption in the autophagy pathway in MJD is required before successful long-term autophagy modulating therapies can be developed.


Assuntos
Autofagia/efeitos dos fármacos , Fármacos do Sistema Nervoso Central/toxicidade , Compostos de Lítio/toxicidade , Doença de Machado-Joseph/tratamento farmacológico , Síndromes Neurotóxicas/fisiopatologia , Sirolimo/análogos & derivados , Animais , Animais Geneticamente Modificados , Ataxina-3/metabolismo , Autofagia/fisiologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Caenorhabditis elegans , Fármacos do Sistema Nervoso Central/administração & dosagem , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Compostos de Lítio/administração & dosagem , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Doença de Machado-Joseph/patologia , Doença de Machado-Joseph/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Síndromes Neurotóxicas/patologia , Sirolimo/administração & dosagem , Sirolimo/toxicidade , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo
11.
Physiol Behav ; 152(Pt A): 85-91, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26386404

RESUMO

Institutionalization adversely impacts children's emotional functioning, proving related to attachment disorders, perhaps most notably that involving indiscriminate behavior, the subject of this report. In seeking to extend work in this area, this research on gene X environment (GXE) interplay investigated whether the serotonin transporter (5-HTTLPR) and val66met Brain-Derived Neurotrophic Factor (BDNF) polymorphisms moderated the effect of institutional care on indiscriminate behavior in preschoolers. Eighty-five institutionalized and 135 home-reared Portuguese children were assessed using Disturbances of Attachment Interview (DAI). GXE results indicated that s/s homozygotes of the 5-HTTLPR gene displayed significantly higher levels of indiscriminate behavior than all other children if institutionalized, something not true of such children when family reared. These findings proved consistent with the diathesis-stress rather than differential-susceptibility model of person×environment interaction. BDNF proved unrelated to indiscriminate behavior. Results are discussed in relation to previous work on this subject of indiscriminate behavior, institutionalization and GXE interaction.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Criança Institucionalizada/psicologia , Apego ao Objeto , Polimorfismo Genético , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Comportamento Social , Criança , Pré-Escolar , Família/psicologia , Feminino , Interação Gene-Ambiente , Predisposição Genética para Doença , Genótipo , Humanos , Lactente , Entrevista Psicológica , Masculino , Modelos Genéticos , Modelos Psicológicos , Portugal
12.
J Dent Res ; 94(4): 615-21, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25691072

RESUMO

The ability to infiltrate various molecules and resins into dental enamel is highly desirable in dentistry, yet transporting materials into dental enamel is limited by the nanometric scale of their pores. Materials that cannot be infiltrated into enamel by diffusion/capillarity are often considered molecules with sizes above a critical threshold, which are often considered to be larger than the pores of enamel. We challenge this notion by reporting the use of electrokinetic flow to transport solutions with molecules with sizes above a critical threshold-namely, an aqueous solution with a high refractive index (Thoulet's solution) and a curable fluid resin infiltrant (without acid etching)-deep into the normal enamel layer. Volume infiltration by Thoulet's solution is increased by 5- to 6-fold, and resin infiltration depths as large as 600 to 2,000 µm were achieved, in contrast to ~10 µm resulting from diffusion/capillarity. Incubation with demineralization solution for 192 h resulted in significant demineralization at noninfiltrated histologic points but not at resin infiltrated. These results open new avenues for the transport of materials in dental enamel.


Assuntos
Esmalte Dentário/metabolismo , Eletro-Osmose/métodos , Eletroforese/métodos , Nanoporos/ultraestrutura , Adolescente , Adulto , Algoritmos , Ação Capilar , Esmalte Dentário/ultraestrutura , Cavidade Pulpar/metabolismo , Cavidade Pulpar/ultraestrutura , Dentina/metabolismo , Dentina/ultraestrutura , Difusão , Humanos , Iodetos/farmacocinética , Compostos de Mercúrio/farmacocinética , Microfluídica/instrumentação , Microfluídica/métodos , Cloreto de Potássio/farmacocinética , Iodeto de Potássio/farmacocinética , Resinas Sintéticas/química , Adulto Jovem
13.
J Hum Hypertens ; 29(6): 373-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25339293

RESUMO

We evaluated the consequences of excluding the first of three blood pressure (BP) readings in different settings: a random population sample (POS, n=1525), a general practice office (GPO, n=942) and a specialized hypertension center (SHC, n=462). Differences between systolic and diastolic BP (SBP and DBP) estimates obtained including and excluding the first reading were compared and their correlation with ambulatory BP monitoring (ABPM) was estimated. The samples were divided into quartiles according to the difference between the third and the first SBP (3-1ΔSBP). SBP decreased through sequential readings, 3-1ΔSBP was -5.5 ± 9.7 mm Hg (P<0.001), -5.1 ± 10.4 mm Hg (P<0.001) and -6.1 ± 9.3 mm Hg (P<0.001) for POS, GPO and SHC, respectively. However, individuals included in the top quartile of 3-1ΔSBP showed their highest values on the third reading. The mean SBP estimate was significantly higher excluding the first reading (P<0.001), but the differences among both approaches were small (1.5-1.6 mm g). Moreover, the correlation between SBP values including and excluding the first reading and daytime ABPM were comparable (r = 0.69 and 0.68, respectively). Similar results were observed for DBP. In conclusion, our study does not support the notion of discarding the first BP measurement and suggests that it should be measured repeatedly, regardless the first value.


Assuntos
Determinação da Pressão Arterial , Adulto , Idoso , Monitorização Ambulatorial da Pressão Arterial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Eur J Hum Genet ; 7(2): 147-56, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10196697

RESUMO

Intergenerational instability is one of the most important features of the disease-associated trinucleotide expansions, leading to variation in size of the repeat among and within families, which manifests as variable age at onset and severity, and is probably the basis for the occurrence of anticipation. Several factors are known to affect the degree of instability, namely the type of repeated sequence, its initial size, the presence or absence of interruptions in the repetitive tract and the gender of the transmitting parent. A recent study demonstrated the effect of an intragenic polymorphism (C987GG/G987GG) in the Machado-Joseph disease causative gene, immediately downstream of the CAG repeat, on the intergenerational instability of the expanded repeat. Surprisingly, there was an effect not only of the specific allele in cis to the disease chromosome, but also of the allele on the normal chromosome, suggesting the existence of an interaction between the normal and expanded alleles that affects the fidelity of replication of the (CAG)n tract. This effect could be a direct effect of the polymorphism studied or, alternatively, this polymorphism could be in disequilibrium with some other flanking sequence which affects the instability of the repetitive (CAG)n tract. In order to confirm the previous results in a different population and to distinguish between a direct and indirect effect of the CGG/GGG polymorphism, we typed 70 parent-progeny pairs for which the variation in the (CAG)n length in the MJD1 gene was known, for three intragenic polymorphisms: C987GG/G987GG and two additional, newly described ones, TAA1118/TAC1118 and A669TG/G669TG. We also typed a control population of 125 individuals for the A669TG/G669TG, C987GG/G987GG and TAA1118/TAC1118 polymorphisms, in an attempt to identify any association between haplotype and (CAG)n length in normal chromosomes, suggestive of an instability-predisposing effect of the repeat-flanking sequences, which could have led to the origin of the MJD mutation in the human population. We confirmed the effect of the C987GG/G987GG polymorphism on intergenerational instability when present in trans. Our results suggest that this effect is restricted to a small region of the gene, immediately downstream of the CAG repeat, which includes this particular nucleotide substitution and the stop codon of the MJD1 cDNA, and is not a more widespread chromosomal effect. The lack of a significant association of any specific intragenic haplotype with larger CAG repeats in normal chromosomes, together with the absence of an effect of the intragenic haplotype in cis on the intergenerational instability of the expanded (CAG)n in MJD families does not indicate the existence of an instability-predisposing haplotype.


Assuntos
Doença de Machado-Joseph/genética , Proteínas do Tecido Nervoso/genética , Polimorfismo Genético , Repetições de Trinucleotídeos , Alelos , Ataxina-3 , Feminino , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Proteínas Nucleares , Proteínas Repressoras
15.
Arch Neurol ; 58(11): 1821-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11708990

RESUMO

BACKGROUND: Direct detection of the gene mutation allows for the confirmation of the clinical diagnosis of Machado-Joseph disease (MJD), the most frequent cause of autosomal dominant spinocerebellar ataxia worldwide. OBJECTIVE: To address the main difficulties in our national MJD predictive testing program. The first was the emergence of intermediate alleles, for which it is not yet possible to determine whether they will cause disease. The second was the issue of homoallelism, ie, homozygosity for 2 normal alleles with exactly the same (CAG)(n) length, which occurs in about 10% of all test results. METHODS: A large pedigree with 1 affected patient carrying a 71 and a 51 CAG repeat and 2 asymptomatic relatives carrying the 51 CAG repeat and normal-size alleles underwent clinical and molecular studies. Intragenic haplotypes for these alleles were determined. A representative sample of the healthy population in the region was obtained to assess the distribution of the normal (CAG)(n) length. We established the genotype for 4 intragenic polymorphisms in the gene for MJD (MJD1) in 21 homoallelic individuals, to distinguish their 2 normal chromosomes. In addition, we developed a new Southern blot method to completely exclude cases of nonamplification of expanded alleles in the homoallelic individuals. RESULTS: The study of the family in which the 51 CAG repeat was found suggests that the allele is apparently not associated with disease. These intermediate alleles were not present in a large sample of the healthy population from the same region. Intragenic polymorphisms allowed distinction of the 2 different normal alleles in all cases of homoallelism. The absence of an expanded allele was also confirmed by Southern blot. CONCLUSIONS: We propose an improved protocol for molecular testing for MJD. These strategies, developed to overcome the practical difficulties mostly in the presymptomatic and prenatal diagnosis of MJD, should prove useful for other polyglutamine-related disorders.


Assuntos
Testes Genéticos/métodos , Doença de Machado-Joseph/diagnóstico , Doença de Machado-Joseph/genética , Proteínas do Tecido Nervoso/genética , Adulto , Idoso , Alelos , Ataxina-3 , Sequência de Bases , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação , Proteínas Nucleares , Linhagem , Polimorfismo Genético/genética , Portugal , Proteínas Repressoras , Expansão das Repetições de Trinucleotídeos
16.
Arch Neurol ; 53(11): 1168-74, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8912491

RESUMO

BACKGROUND: Machado-Joseph disease (MJD) is a type of autosomal dominant spinocerebellar ataxia for which molecular diagnosis is available. We identified 4 families segregating the MJD mutation in which no unequivocal clinical diagnosis could be established prior to molecular testing. Ethnic background, clinical, and molecular characteristics of 19 individuals carrying the MJD mutation in these 4 families were compared with a group of 32 Portuguese families who were clinically diagnosed as having MJD and were found to carry the MJD mutation. RESULTS: Several factors seemed to have an impact in the accuracy of the clinical diagnosis, such as ethnic origin; the number of affected individuals available for examination in each family; the absence of patients showing specific clinical features, such as extrapyramidal signs; and the size of the expanded CAG repeat in the MJD gene. CONCLUSION: Since the recognition of MJD based solely on clinical grounds might sometimes be misleading, a search for the MJD mutation should be performed in patients with a clinical diagnosis of spinocerebellar degeneration.


Assuntos
Doença de Machado-Joseph/patologia , Adulto , Córtex Cerebral/patologia , Feminino , Humanos , Doença de Machado-Joseph/genética , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Linhagem
17.
Neurology ; 46(1): 214-8, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8559378

RESUMO

The spinocerebellar ataxias (SCAs) are a heterogeneous group of neurodegenerative disorders varying in both clinical manifestations and mode of inheritance. Six different genes causing autosomal dominant SCA are mapped: SCA1, SCA2, Machado-Joseph disease (MJD)/SCA3, SCA4, SCA5, and dentatorubropallidoluysian atrophy (DRPLA). Expansions of an unstable trinucleotide CAG repeat cause three of these disorders: SCA type 1 (SCA1), MJD, and DRPLA. We determine the frequency of the SCA1, DRPLA, and MJD mutations in a large group of unrelated SCA patients with various patterns of inheritance and different ethnic backgrounds. We studied 92 unrelated SCA patients. The frequency of the SCA1 mutation was 3% in the overall patient group and 10% in the non-Portuguese dominantly inherited SCA subgroup. We found that DRPLA mutation in only one Japanese patient, who was previously diagnosed with this disease. We identified the MJD mutation in 41% of the overall patient group, which included 38 autosomal dominant kindreds of Portuguese origin; the frequency of the MJD mutation among the non-Portuguese dominantly inherited cases was 17%. These results suggest that SCA may be occasionally caused by the SCA1 mutation and rarely caused by the DRPLA mutation and that, to date, the MJD mutation seems to be the most common cause of dominantly inherited SCA. Finally, our results suggest that recessively inherited cases of SCA are not caused by the known trinucleotide repeat expansions.


Assuntos
Química Encefálica , Encefalopatias/genética , Doença de Machado-Joseph/genética , Degenerações Espinocerebelares/genética , Corpo Estriado/química , Giro Denteado/química , Globo Pálido/química , Humanos , Mutação , Reação em Cadeia da Polimerase , Sequências Repetitivas de Ácido Nucleico
18.
J Neuroimmunol ; 143(1-2): 112-5, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14575926

RESUMO

Multiple sclerosis (MS) is common in Europe affecting up to 1:500 people. In an effort to identify genes influencing susceptibility to the disease, we have performed a population-based whole genome screen for association. In this study, 6000 microsatellite markers were typed in separately pooled DNA samples from MS patients (n=188) and matched controls (n=188). Interpretable data was obtained from 4661 of these markers. Refining analysis of the most promising markers identified 10 showing potential evidence for association.


Assuntos
Predisposição Genética para Doença , Testes Genéticos/métodos , Genoma Humano , Esclerose Múltipla/genética , Adolescente , Adulto , Alelos , Estudos de Casos e Controles , Feminino , Frequência do Gene , Testes Genéticos/estatística & dados numéricos , Humanos , Cooperação Internacional , Desequilíbrio de Ligação/genética , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Esclerose Múltipla/epidemiologia , Portugal/epidemiologia
19.
Am J Med Genet ; 81(2): 134-8, 1998 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-9613852

RESUMO

The spinocerebellar ataxias (SCAs) are clinically and genetically a heterogeneous group of neurodegenerative disorders. To date, eight different loci causing SCA have been identified: SCA1, SCA2, Machado-Joseph disease (MJD)/SCA3, SCA4, SCA5, SCA6, SCA7, and dentatorubropallidoluysian atrophy (DRPLA). Expansion of a CAG repeat in the disease genes has been found in five of these disorders. To estimate the relative frequencies of the SCA1, DRPLA, MJD, SCA2, and SCA6 mutations among Portuguese ataxia patients, we collected DNA samples from 48 ataxia families and performed polymerase chain reaction (PCR) amplification of the CAG repeat mutations on chromosomes 6p, 12p, 14q, 12q, and 19p, respectively. Fifty-five individuals belonging to 34 dominant families (74%) had an expanded CAG repeat at the MJD gene. In five individuals from two kindreds with a dominant pattern of inheritance (4%), an expanded CAG repeat at the SCA2 gene was found. In MJD patients, the normal allele size ranged from 13 to 41, whereas the mutant alleles contained 65 to 80 repeats. For the SCA2 patients, normal alleles had 22 or 23, while expanded alleles had between 36 and 47 CAG units. We did not find the SCA1, DRPLA, or SCA6 mutations in our group of families. The MJD mutation remains the most common cause of SCA in Portugal, while a small number of cases are caused by mutations at the SCA2 gene, and 22% are due to still unidentified genes.


Assuntos
Degenerações Espinocerebelares/genética , Repetições de Trinucleotídeos , Adolescente , Adulto , Idade de Início , Idoso , Alelos , Ataxina-1 , Ataxinas , Canais de Cálcio/genética , Cromossomos Humanos , Saúde da Família , Feminino , Genes Dominantes , Humanos , Doença de Machado-Joseph/genética , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Portugal , Proteínas/genética
20.
Neurosci Res ; 28(4): 373-7, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9274833

RESUMO

Three cDNA clones for the Machado-Joseph disease gene (MJD1) were isolated, two of which have a new exon sequence and a distinct 3' terminal nucleotide sequence resulting in a new carboxyl terminal domain in the translated product. The nucleotide sequence of the other one is similar to the previously published one except for five polymorphisms, one of which is a single nucleotide substitution resulting in a change from the stop codon (TAA; allele A) to a tyrosine residue (TAC; allele C). Genetic analysis results suggest that Japanese MJD mutations are associated with allele A.


Assuntos
Doença de Machado-Joseph/metabolismo , Proteínas do Tecido Nervoso/genética , Sequência de Aminoácidos , Ataxina-3 , Sequência de Bases , Códon/genética , Humanos , Doença de Machado-Joseph/genética , Dados de Sequência Molecular , Proteínas Nucleares , Polimorfismo Genético , Proteínas Repressoras
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