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1.
Nat Genet ; 29(1): 66-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11528394

RESUMO

The dystonias are a common clinically and genetically heterogeneous group of movement disorders. More than ten loci for inherited forms of dystonia have been mapped, but only three mutated genes have been identified so far. These are DYT1, encoding torsin A and mutant in the early-onset generalized form, GCH1 (formerly known as DYT5), encoding GTP-cyclohydrolase I and mutant in dominant dopa-responsive dystonia, and TH, encoding tyrosine hydroxylase and mutant in the recessive form of the disease. Myoclonus-dystonia syndrome (MDS; DYT11) is an autosomal dominant disorder characterized by bilateral, alcohol-sensitive myoclonic jerks involving mainly the arms and axial muscles. Dystonia, usually torticollis and/or writer's cramp, occurs in most but not all affected patients and may occasionally be the only symptom of the disease. In addition, patients often show prominent psychiatric abnormalities, including panic attacks and obsessive-compulsive behavior. In most MDS families, the disease is linked to a locus on chromosome 7q21 (refs. 11-13). Using a positional cloning approach, we have identified five different heterozygous loss-of-function mutations in the gene for epsilon-sarcoglycan (SGCE), which we mapped to a refined critical region of about 3.2 Mb. SGCE is expressed in all brain regions examined. Pedigree analysis shows a marked difference in penetrance depending on the parental origin of the disease allele. This is indicative of a maternal imprinting mechanism, which has been demonstrated in the mouse epsilon-sarcoglycan gene.


Assuntos
Proteínas do Citoesqueleto/genética , Distúrbios Distônicos/genética , Glicoproteínas de Membrana/genética , Mutação , Mioclonia/genética , Adolescente , Northern Blotting , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Linhagem , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sarcoglicanas , Síndrome , Células Tumorais Cultivadas
2.
Neuroscience ; 146(2): 481-8, 2007 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-17383103

RESUMO

This paper describes a significant biotechnological advancement by creating a minimalist serum-free defined system to co-culture rat mammalian nerve and muscle cells in order to form functional neuromuscular junctions. To date, all the known in vitro nerve and muscle co-culture models use serum containing media; and while functional neuromuscular junctions (NMJ) are described, they failed to detail or quantify the minimum factors needed to recreate the NMJ in vitro. In this work, we demonstrate the development of a defined motoneuron and muscle co-culture system resulting in the formation of NMJs including: 1) a new culture technique, 2) a novel serum-free medium formulation and 3) a synthetic self-assembled monolayer (SAM) substrate N-1 [3-(trimethoxysilyl) propyl] diethylenetriamine (DETA). We characterized the culture by morphology, immunocytochemistry, electrophysiology and videography. This model system provides a better understanding of the minimal growth factor and substrate interactions necessary for NMJ formation and provides a basic system that can be utilized for nerve-muscle tissue engineering, regenerative medicine and development of limb prosthetics.


Assuntos
Meios de Cultivo Condicionados/metabolismo , Neurônios Motores/fisiologia , Mioblastos/fisiologia , Junção Neuromuscular/fisiologia , Animais , Bungarotoxinas/metabolismo , Células Cultivadas , Técnicas de Cocultura , Meios de Cultura Livres de Soro/metabolismo , Embrião de Mamíferos , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Potenciais da Membrana/efeitos da radiação , Modelos Biológicos , Cadeias Pesadas de Miosina/metabolismo , Proteínas de Neurofilamentos/metabolismo , Junção Neuromuscular/efeitos dos fármacos , Técnicas de Patch-Clamp/métodos , Poliaminas/farmacologia , Ratos , Sinaptofisina/metabolismo
3.
Mutat Res ; 138(1): 71-4, 1984 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6541755

RESUMO

The antiepileptic drugs, phenytoin, primidone and phenobarbital, were tested in Chinese hamster ovary (CHO) cells for their ability to induce sister-chromatid exchanges (SCEs) and structural chromosomal aberrations (CAs), with and without metabolic activation. SCEs and CAs were analyzed in the same cell population. The results are negative.


Assuntos
Mutação/efeitos dos fármacos , Fenobarbital/toxicidade , Fenitoína/toxicidade , Primidona/toxicidade , Animais , Biotransformação , Células Cultivadas , Aberrações Cromossômicas , Cricetinae , Feminino , Ovário , Troca de Cromátide Irmã/efeitos dos fármacos
4.
Mutat Res ; 73(1): 125-31, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6973084

RESUMO

In cultures of human peripheral lymphocytes the frequencies of Trenimon-induced SCEs in second post-treatment metaphases and of structural chromosomal aberrations in first, second and third post-treatment metaphases were clearly lower at late as compared with early fixation times. These results, which are discussed, indicate that T cells (early dividing) are more sensitive with respect to the induction of SCEs and structural chromosomal aberrations by Trenimon as compared with B cells (late dividing).


Assuntos
Aberrações Cromossômicas , Troca Genética/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Troca de Cromátide Irmã/efeitos dos fármacos , Triaziquona/farmacologia , Adulto , Linfócitos B/efeitos dos fármacos , Ciclo Celular , Divisão Celular , Humanos , Masculino , Metáfase , Linfócitos T/efeitos dos fármacos , Fatores de Tempo
5.
Mutat Res ; 97(6): 437-47, 1982 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6958973

RESUMO

A test is described in which human peripheral blood is enclosed in dialysis bags and exposed to human urine. After the treatment, the blood is cultivated in the presence of bromodeoxyuridine, and metaphases are analyzed with respect to the frequencies of sister-chromatid exchanges (SCE). Urine from clinically healthy people and from epileptic patients on therapy with anti-epileptic drugs did not lead to an elevation of SCE frequencies. Urine from cancer patients treated with a multi-drug combination therapy including cyclophosphamide led to a significant increase in the frequencies of SCEs.


Assuntos
Troca Genética/efeitos dos fármacos , Ciclofosfamida/urina , Leucemia Linfoide/tratamento farmacológico , Linfócitos/efeitos dos fármacos , Mutagênicos/urina , Mutação , Troca de Cromátide Irmã/efeitos dos fármacos , Adolescente , Biotransformação , Bromodesoxiuridina/farmacologia , Células Cultivadas , Criança , Ciclofosfamida/farmacologia , Ciclofosfamida/uso terapêutico , Diálise , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Masculino , Mutagênicos/farmacologia
6.
Mutat Res ; 95(2-3): 105-18, 1982 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6750378

RESUMO

To elucidate which metabolic pathway leads to the ultimate mutagenic and teratogenic metabolite of cyclophosphamide (CPA), the mutagenicity in vitro as well as the teratogenicity in vivo and the pharmacokinetics of CPA and several deuterated analogs (5,5-d2-CPA, 4,4-d2-CPA and 4,4-6,6-d4-CPA) were compared. 5,5-d2-CPA was less mutagenic (isotope effects between 1.7 and 12.3 were found for sister-chromatid exchanges and structural chromosomal aberrations in CHO cells and in the Ames test) and less teratogenic (deuterium isotope effect between 2 and 3) than CPA and the other deuterated analogs. Because the concentrations of 5,5-d2-CPA in pregnant mice and their embryos were equal to or even exceeded those of CPA and the other deuterated analogs, a particular metabolic pathway involving a fission of the C-D or C-H bond on the C-5 rather than the parent drug must be responsible for the isotope effect observed. It had previously been shown (Cox et al., 1976) that the 5,5-d2-CPA has a decreased anti-tumor activity in vivo (isotope effect 7-13) which was accompanied by a decreased formation of phosphoramide mustard and acrolein in vitro (isotope effect 5.3). Our results suggest that phosphoramide mustard is an important proximate metabolite of CPA with regard to the mutagenicity and teratogenicity of the drug. These results show for the first time that labeling of drugs with stable isotopes offers a promising approach to the study of the mechanism of the mutagenic and teratogenic actions of drugs.


Assuntos
Ciclofosfamida/farmacologia , Mutagênicos , Teratogênicos , Animais , Ciclofosfamida/análogos & derivados , Relação Dose-Resposta a Droga , Feminino , Cinética , Camundongos , Testes de Mutagenicidade , Gravidez , Salmonella typhimurium/genética
7.
Rev Saude Publica ; 27(1): 15-22, 1993 Feb.
Artigo em Português | MEDLINE | ID: mdl-8310264

RESUMO

Many studies have been published about the relationship between life style and genetic risk factors and stroke and heart attack, but there have been few about the relationship between atmospheric pollution, specifically with carbon monoxide, and temperature and stroke and heart attack. With a view to filling this gap the relationship between values of carbon monoxide concentration in the air, maximum and average by day, and maximum temperature by day and the number of new cases of CVA and IM admitted as emergencies at the biggest hospital complex of S. Paulo city was analysed. If was concluded, by the use of multivariable regression analysis, that 2.1% and 4.9% of heart attack admissions were due to carbon monoxide air pollution and high temperature, respectively. 2.8% of stroke admissions were due high temperature. Stroke and carbon monoxide were not associated in this population.


Assuntos
Monóxido de Carbono/efeitos adversos , Transtornos Cerebrovasculares/etiologia , Temperatura Alta/efeitos adversos , Infarto do Miocárdio/etiologia , Brasil/epidemiologia , Transtornos Cerebrovasculares/epidemiologia , Humanos , Incidência , Infarto do Miocárdio/epidemiologia , Estudos Retrospectivos , Fatores de Risco
8.
Rev Saude Publica ; 33(3): 219-29, 1999 Jun.
Artigo em Português | MEDLINE | ID: mdl-10456994

RESUMO

In Brazil, in recent years, as a result of the increasing participation of county authorities in health care, a need for tools which would contribute to the better preparation of local administrators, complementary to the activities of a more academic nature, has been recognized. One of the possible alternatives is the exploitation of experiences, regarded as successful, in local health care planning and administration, by using them as material for "case studies" in activities with selected groups of health care administrators thus, stimulating the identification of those elements which contributed to the favorable results attained, and their interactions, in the quest for analogies which would facilitate the identification of new perspectives for their own situations. In this article an experience of a "case studies" development, in response to a demand from UNICEF, based on 8 counties in from the North and Northeast, which were successful in using a "focus approach" in their organization of data and their utilisation in a seminar with 21 local managers from both regions, is presented. During the seminar the local health managers attained greater knowledge of the strategies implemented and identified feasible intervention alternatives. The methodological proposition of teaching on the basis of case studies, using a conceptual strategy of grouping experiences according to specific dimensions enabled local health managers to learn from their practical experiences.


Assuntos
Administradores de Instituições de Saúde/educação , Administração de Serviços de Saúde , Capacitação em Serviço/métodos , Brasil , Currículo , Humanos , Técnicas de Planejamento
10.
11.
Z Erkr Atmungsorgane ; 151(2): 143-50, 1978.
Artigo em Alemão | MEDLINE | ID: mdl-726536

RESUMO

52 persons with bronchial carcinoma found by reason of complaints by the Chest Clinic were critically evaluated. Cough, hemoptysis and thoracic pain are of the first place in the range of frequency of complaints caused by the tumour. The time elapsing between the onset of the troubles to the first medical visit and from this consultation to the hospital admission was analysed. The complaints were existing more than 4 weeks in nearly half of all patient before they went to a physician. The causes of delay are discussed. The necessity of immediate x-ray examination of persons in the age endangered by cancer is emphasized if complaints suspicious to carcinoma especially the three symptoms mentioned above persisting more than three weeks inspite of treatment. For that purpose the personal conversation with persons from risk groups and continuous cooperation with other physicians in the territory are important.


Assuntos
Neoplasias Brônquicas/diagnóstico , Adulto , Idoso , Peso Corporal , Bronquite/etiologia , Hemoptise/etiologia , Humanos , Pessoa de Meia-Idade , Dor/etiologia , Tempo
12.
Z Erkr Atmungsorgane ; 158(3): 314-8, 1982.
Artigo em Alemão | MEDLINE | ID: mdl-7136047

RESUMO

34 persons with pulmonary fibrosis found by the Chest Clinic were evaluated. Nearly half of all patients were sent by other physicians. Dyspnea and bronchitis are of the first place in the range of frequency of complaints. In some cases the troubles were existing for 20 years. In the main cause of delay was diagnosis' failing inspite of suspicious x-ray picture and troubles mentioned above.


Assuntos
Fibrose Pulmonar/diagnóstico , Tuberculose Pulmonar/diagnóstico , Adulto , Alveolite Alérgica Extrínseca/diagnóstico , Criança , Diagnóstico Diferencial , Dispneia/etiologia , Feminino , Humanos , Masculino
13.
Dtsch Med Wochenschr ; 108(28-29): 1106-10, 1983 Jul 15.
Artigo em Alemão | MEDLINE | ID: mdl-6861656

RESUMO

High temperatures, night sweat, chest pain, cough and dyspnoea suddenly occurred in a 54-year-old patient. The serious disease was accompanied by variable pulmonary infiltrations. Chemical pathology showed maximally increased sedimentation rates, slight leucocytosis and anaemia. Complete serology was negative. The occurrence of large intestinal ileus required laparatomy and after commencement of treatment with steroids the overall state improved, pulmonary symptoms disappeared, and radiographically demonstrable infiltration were clearly regressing. Histology revealed presence of acute ulcerative colitis. Lung infiltrates probably represented extraintestinal manifestation of the chronic inflammatory bowel disease. In contrast to experience from the literature lung infiltrations in this case preceded clinical manifestations of the underlying disease.


Assuntos
Colite Ulcerativa/complicações , Tosse/etiologia , Dispneia/etiologia , Colite Ulcerativa/diagnóstico , Colonoscopia , Colostomia , Humanos , Obstrução Intestinal/etiologia , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia
14.
Cell ; 76(3): 567-76, 1994 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-8313476

RESUMO

One monomeric and three oligomeric potato spindle tuber viroid (PSTVd) cDNA units were introduced into the tobacco genome via the Agrobacterium-mediated leaf-disc transformation. Southern analysis of the integrates revealed that only their PSTVd-specific sequences become fully methylated, whereas the flanking T-DNA and the genomic plant DNA remain unaltered. Viroid cDNA methylation could only be observed after autonomous viroid RNA-RNA replication had taken place in these plants. These findings demonstrate that a mechanism of de novo methylation of genes might exist that can be induced and targeted in a sequence-specific manner by their own mRNA.


Assuntos
DNA Viral/metabolismo , DNA/metabolismo , Genes de Plantas , Nicotiana/metabolismo , Plantas Tóxicas , RNA Viral/metabolismo , Rhizobium/fisiologia , Sequência de Bases , Northern Blotting , Southern Blotting , Metilação , Dados de Sequência Molecular , Plantas Geneticamente Modificadas , Mapeamento por Restrição , Rhizobium/genética , Nicotiana/genética , Viroides/fisiologia , Replicação Viral
15.
S Afr Med J ; 77(3): 135-7, 1990 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-2305322

RESUMO

The patterns of analgesic ingestion in urbanised black patients with gastric ulcer disease were assessed. A strong statistical association was found between the quantity ingested and the disease. There was no difference in the type of analgesic and smoking and alcohol habits between gastric ulcer patients and controls in this study.


Assuntos
Analgésicos/efeitos adversos , Úlcera Gástrica/induzido quimicamente , Adulto , Negro ou Afro-Americano , Consumo de Bebidas Alcoólicas , Analgésicos/administração & dosagem , População Negra , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fumar/efeitos adversos , África do Sul , População Urbana
16.
J Clin Gastroenterol ; 11(6): 671-4, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2584669

RESUMO

Review of biopsy specimens showed that a patient incorrectly diagnosed 7 years ago as having Crohn's disease actually had histologically proven gastrointestinal tuberculosis of 7 years' duration. It is significant that gastrointestinal tuberculosis and Crohn's disease can mimic each other not only in their clinical, radiologic, and histologic manifestations but also temporally. We discuss the interrelationship between AIDS, tuberculosis, and inflammatory bowel disease.


Assuntos
Doença de Crohn/patologia , Intestino Delgado/patologia , Tuberculose Gastrointestinal/patologia , Síndrome da Imunodeficiência Adquirida/complicações , Adulto , Biópsia , Diagnóstico Diferencial , Erros de Diagnóstico , Humanos , Masculino , Fatores de Tempo , Tuberculose Gastrointestinal/complicações
17.
Plant Mol Biol ; 31(1): 113-25, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8704144

RESUMO

The sequence variants of the signal recognition particle (SRP) RNA gene family from four tomato cultivars have been isolated and characterized which indicated the existence of SRP RNA pseudogenes. Sequence analysis revealed two conserved sequence motifs in the upstream region, a TATA-like box and an upstream sequence element (USE), 'TCCCACATCG', both located at a conserved distance to the transcription start point. These elements are identical to the DNA-dependent RNA polymerase III (pol III)-specific promoters of U-rich small nuclear RNA (UsnRNA) genes of plants. Moreover, T-rich stretches are found at the 3' end of the coding regions of the SRP RNA genes which could act as typical pol III termination signals. These findings and recent results from site-directed mutation analysis of the SRP RNA genes from Arabidopsis thaliana indicate that, in contrast to mammalian systems, plant pol III SRP RNA genes are most probably regulated by external promoter elements. According to the identical promoter organization between plant U3-, U6snRNA, MRP-like RNA and SRP RNA genes, one can group these genes into the 'pol III(EXT)USE' subclass of externally regulated USE-dependent pol III genes.


Assuntos
Família Multigênica , RNA de Plantas/genética , Partícula de Reconhecimento de Sinal/genética , Solanum lycopersicum/genética , Sequência de Bases , Clonagem Molecular , Sequência Conservada , Regulação da Expressão Gênica de Plantas , Dados de Sequência Molecular , Folhas de Planta/genética , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Sequências Repetitivas de Ácido Nucleico , Mapeamento por Restrição
18.
S Afr Med J ; 80(11-12): 543-5, 1991 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-1745937

RESUMO

Prevalences of non-infective bowel diseases are very low in South African urban blacks compared with the white population. In seeking elucidation, using breath hydrogen measurements in series of black and white subjects, small-bowel transit time was determined, and the malabsorption of maize, wheat, and rice investigated. Median transit times in both ethnic groups were similar. Rice was fully, but wheat incompletely absorbed by both groups. Maize, the staple food of blacks, was incompletely absorbed by them, although completely absorbed by the white subjects. Carbohydrate consumption is high in the black population (60-65% of total energy intake). It is probable that in blacks, despite their now eating a low-fibre diet, an expected increase in large-bowel diseases has been inhibited in part by the protective mechanism of fermentation of malabsorbed maize and wheat.


Assuntos
População Negra , Carboidratos da Dieta/metabolismo , Oryza/metabolismo , Triticum/metabolismo , Zea mays/metabolismo , Adulto , Testes Respiratórios , Feminino , Humanos , Hidrogênio/análise , Absorção Intestinal , Lactulose/metabolismo , Masculino , África do Sul , População Urbana
19.
Mov Disord ; 15(6): 1238-41, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11104212

RESUMO

A 3-base pair (GAG) deletion in the DYT1 gene has recently been found to be responsible for most cases of early-onset primary generalized dystonia. In some cases, this mutation has been associated with writer's cramp. To determine the frequency of this mutation in a larger series of patients, we examined 44 index patients with sporadic or familial (seven patients) writer's cramp for the presence of the DYT1 GAG deletion, including eight patients with segmental dystonia involving at least one upper limb. We found the mutation in none of these index patients, which confirms that isolated writer's cramp is only in rare cases a phenotypic manifestation of this mutation, even if a positive family history of writer's cramp is present.


Assuntos
Proteínas de Transporte/genética , Distonia Muscular Deformante/genética , Distúrbios Distônicos/genética , Chaperonas Moleculares , Mutação , Adulto , Pareamento de Bases , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Deleção de Sequência
20.
Plant Mol Biol ; 27(4): 669-80, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7727745

RESUMO

Molecular cloning of 30 cDNAs and subsequent characterization of the corresponding SRP RNA from four cultivars of tomato (Lycopersicon esculentum) revealed altogether 14 sequence variants, which could be ordered into six groups. The expression of five representatives from these groups was examined by reverse transcriptase-polymerase chain reaction (RT-PCR) in different cultivars and different tissues. Although one cultivar-specific SRP RNA variant could be detected in the leaf SRP RNA population, identical SRP RNA populations seem to be present in the four different cultivars as well as in different tissues, such as leaves, flowers, fruits, stems and roots. Sequence comparison revealed that several variants might have evolved by recombination of two different SRP RNA sequences. On the basis of five SRP RNA variants, the current secondary structure model was refined and a new conserved structural element was detected. Comparative sequence analysis of domain II from all known SRP RNA homologues reveals a remarkable conservation of this element. As demonstrated previously, the corresponding area overlaps with a region that interact with the SRPp68/p72 heterodimer and/or with ribosomes. Based on structural and functional considerations, we propose that the domain IV structure together with the highly conserved area of domain II constitutes the essential core of the SRP RNA.


Assuntos
RNA de Plantas/genética , Partícula de Reconhecimento de Sinal/genética , Solanum lycopersicum/genética , Sequência de Bases , Clonagem Molecular , Sequência Conservada , DNA Complementar , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA de Plantas/metabolismo
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