Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 166
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Psychol Med ; 47(12): 2071-2080, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28374659

RESUMO

BACKGROUND: The enhanced error monitoring in patients with obsessive-compulsive disorder (OCD), typically measured with the error-related negativity (ERN), has been found to be temporally stable and independent of symptom expression. Here, we examined whether the error monitoring in patients with OCD could be experimentally modulated by individually tailored symptom provocation. METHOD: Twenty patients with OCD and 20 healthy controls performed a flanker task in which OCD-relevant or neutral pictures were presented prior to a flanker stimulus. An individualized stimulus set consisting of the most provoking images in terms of OCD symptoms was selected for each patient with OCD. Response-locked event-related potentials were recorded and used to examine the error-related brain activity. RESULTS: Patients with OCD showed larger ERN amplitudes than did control subjects in both the OCD-symptom provocation and neutral conditions. Additionally, while patients with OCD exhibited a significant increase in the ERN under the OCD-symptom provocation condition when compared with the neutral condition, control subjects showed no variation in the ERN between the conditions. CONCLUSIONS: Our results strengthen earlier findings of hyperactive error monitoring in OCD, as indexed by higher ERN amplitudes in patients with OCD than in controls. Importantly, we showed that the patients' overactive error-signals were experimentally enhanced by individually tailored OCD-symptom triggers, thus suggesting convincing evidence between OCD-symptoms and ERN. Such findings imply that therapeutic interventions should target affective regulation in order to alleviate the perceived threatening value of OCD triggers.


Assuntos
Atenção/fisiologia , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Transtorno Obsessivo-Compulsivo/fisiopatologia , Desempenho Psicomotor/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
2.
Mol Psychiatry ; 20(10): 1205-11, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25421403

RESUMO

Despite optimal pharmacotherapy and cognitive-behavioral treatments, a proportion of patients with obsessive-compulsive disorder (OCD) remain refractory to treatment. Neurosurgical ablative or nondestructive stimulation procedures to treat these refractory patients have been investigated. However, despite the potential benefits of these surgical procedures, patients show significant surgery-related complications. This preliminary study investigated the use of bilateral thermal capsulotomy for patients with treatment-refractory OCD using magnetic resonance-guided focused ultrasound (MRgFUS) as a novel, minimally invasive, non-cranium-opening surgical technique. Between February and May 2013, four patients with medically refractory OCD were treated with MRgFUS to ablate the anterior limb of the internal capsule. Patients underwent comprehensive neuropsychological evaluations and imaging at baseline, 1 week, 1 month and 6 months following treatment. Outcomes were measured with the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), the Hamilton Rating Scale for Depression (HAM-D) and the Hamilton Rating Scale for Anxiety (HAM-A), and treatment-related adverse events were evaluated. The results showed gradual improvements in Y-BOCS scores (a mean improvement of 33%) over the 6-month follow-up period, and all patients showed almost immediate and sustained improvements in depression (a mean reduction of 61.1%) and anxiety (a mean reduction of 69.4%). No patients demonstrated any side effects (physical or neuropsychological) in relation to the procedure. In addition, there were no significant differences found in the comprehensive neuropsychological test scores between the baseline and 6-month time points. This study demonstrates that bilateral thermal capsulotomy with MRgFUS can be used without inducing side effects to treat patients with medically refractory OCD. If larger trials validate the safety, effectiveness and long-term durability of this new approach, this procedure could considerably change the clinical management of treatment-refractory OCD.


Assuntos
Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Transtorno Obsessivo-Compulsivo/cirurgia , Adulto , Feminino , Humanos , Cápsula Interna/cirurgia , Imagem por Ressonância Magnética Intervencionista/métodos , Masculino , Testes Neuropsicológicos , Procedimentos Neurocirúrgicos/métodos , Procedimentos Cirúrgicos Ultrassônicos/métodos , Ultrassonografia de Intervenção/métodos
3.
Transfus Med ; 26(5): 349-354, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27634577

RESUMO

OBJECTIVES: To evaluate the clinical significance of GP. Mur antigen-negative blood selection for transfusion in patients with anti-'Mia ' records. BACKGROUND: The GP. Mur RBC phenotype is prevalent (7·3%) in Taiwan. Antibodies against GP. Mur (anti-'Mia ') are identified in 1·24% of our population, and anti-'Mia ' screening using GP. Mur RBC has been routine for Taiwan's blood banks. However, due to the lack of commercial antibodies, only cross-matching was used to prevent transfusion of GP. Mur-positive blood to patients with anti-'Mia ' in most hospitals. There is still a risk of GP. Mur-positive RBC exposure and subsequent anti-'Mia '-related transfusion reactions. METHODS: Since February 2014, GP. Mur antigen-negative RBCs identified by reaction with anti-'Mia '-positive serum were selected for blood recipients with anti-'Mia ' records. The transfusion reactions between January 2013 and January 2014 were compared with those that occurred between February 2014 and July 2015. RESULTS: The transfusion reaction rate was significantly higher in anti-'Mia '-positive blood recipients compared to total subjects receiving an RBC transfusion before GP. Mur-negative donor RBC selection. After antigen-negative RBC selection, the transfusion reaction frequency in subjects with anti-'Mia ' became similar to total blood recipients. IgG form anti-'Mia ' antibodies were present in all cases of probable anti-'Mia '-related transfusion reactions. The time required for anti-'Mia ' boosting after transfusion was around 4-21 days. CONCLUSION: Selection of GP. Mur-negative RBC for transfusion to patients with anti-'Mia ' records could decrease the rate of transfusion reaction and antibody boosting. This procedure should be incorporated into blood bank routines in areas where anti-'Mia ' is prevalent.


Assuntos
Doadores de Sangue , Antígenos de Grupos Sanguíneos/sangue , Tipagem e Reações Cruzadas Sanguíneas/métodos , Seleção do Doador/métodos , Eritrócitos/metabolismo , Glicoforinas/metabolismo , Isoanticorpos/sangue , Eritrócitos/citologia , Feminino , Humanos , Masculino
4.
Nat Genet ; 24(1): 66-70, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10615130

RESUMO

The survival motor neuron gene is present in humans in a telomeric copy, SMN1, and several centromeric copies, SMN2. Homozygous mutation of SMN1 is associated with proximal spinal muscular atrophy (SMA), a severe motor neuron disease characterized by early childhood onset of progressive muscle weakness. To understand the functional role of SMN1 in SMA, we produced mouse lines deficient for mouse Smn and transgenic mouse lines that expressed human SMN2. Smn-/- mice died during the peri-implantation stage. In contrast, transgenic mice harbouring SMN2 in the Smn-/- background showed pathological changes in the spinal cord and skeletal muscles similar to those of SMA patients. The severity of the pathological changes in these mice correlated with the amount of SMN protein that contained the region encoded by exon 7. Our results demonstrate that SMN2 can partially compensate for lack of SMN1. The variable phenotypes of Smn-/-SMN2 mice reflect those seen in SMA patients, providing a mouse model for this disease.


Assuntos
Atrofia Muscular Espinal/genética , Proteínas do Tecido Nervoso/genética , Animais , Sequência de Bases , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Primers do DNA , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Atrofia Muscular Espinal/patologia , Proteínas de Ligação a RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas do Complexo SMN , Proteína 1 de Sobrevivência do Neurônio Motor , Proteína 2 de Sobrevivência do Neurônio Motor , Transgenes
6.
Tree Physiol ; 35(12): 1343-55, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26358048

RESUMO

During periods of water deficit, growing roots may shrink, retaining only partial contact with the soil. In this study, known mathematical models were used to calculate the root-soil air gap and water flow resistance at the soil-root interface, respectively, of Robinia pseudoacacia L. under different water conditions. Using a digital camera, the root-soil air gap of R. pseudoacacia was investigated in a root growth chamber; this root-soil air gap and the model-inferred water flow resistance at the soil-root interface were compared with predictions based on a separate outdoor experiment. The results indicated progressively greater root shrinkage and loss of root-soil contact with decreasing soil water potential. The average widths of the root-soil air gap for R. pseudoacacia in open fields and in the root growth chamber were 0.24 and 0.39 mm, respectively. The resistance to water flow at the soil-root interface in both environments increased with decreasing soil water potential. Stepwise regression analysis demonstrated that soil water potential and soil temperature were the best predictors of variation in the root-soil air gap. A combination of soil water potential, soil temperature, root-air water potential difference and soil-root water potential difference best predicted the resistance to water flow at the soil-root interface.


Assuntos
Rizosfera , Robinia/metabolismo , Solo/química , Água/metabolismo , Modelos Biológicos , Raízes de Plantas/metabolismo , Temperatura
7.
Hum Mutat ; 14(6): 542, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10571953

RESUMO

Type I oculocutaneous albinism (OCA1) is an autosomal recessive disorder, which is caused by the reduction or the absence of tyrosinase activity in melanocytes of the skin, hair and eyes. Although tyrosinase mutations of OCA1 have been extensively analyzed in most populations worldwide, there is no systemic study of OCA1 mutation in Chinese patients. By use of single strand conformation polymorphism and direct sequencing, we had detected 21 mutant alleles out of 24 OCA1 chromosomes screened (87.5%). Detected mutant alleles include one splicing site, three insertion/deletion and five missense mutations, of which the splicing site nucleotide alteration (IVS 1-3C>G) and two each of the insertion/deletion (232-233 ins GGG and 861-862 del TT) and missense mutations (Cys 289 Gly and Trp 400 Leu) are novel. The ins/del mutations accounts for about 37.5% in Chinese OCA1 alleles. The 232-233 ins GGG, one of the novel mutations, was found to be most frequent (25%) among the OCA1 alleles in Chinese. Through this study, we found that while some of the OCA mutant alleles were identified in other populations, ethnic difference still exists. Hum Mutat 14:542, 1999.


Assuntos
Albinismo Oculocutâneo/enzimologia , Albinismo Oculocutâneo/genética , Monofenol Mono-Oxigenase/genética , Alelos , Sequência de Bases , China/etnologia , Humanos , Mutagênese Insercional , Mutação de Sentido Incorreto , Polimorfismo Conformacional de Fita Simples , Splicing de RNA , Deleção de Sequência , Taiwan
8.
J Clin Endocrinol Metab ; 85(2): 597-600, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10690861

RESUMO

Congenital adrenal hyperplasia (CAH) is a common autosomal recessive disorder mainly caused by defects in the steroid 21-hydroxylase (CYP21) gene. We screened 1,000 healthy people, using a previously developed differential PCR method combined with single-strand conformation polymorphism and amplification-created restriction site methods for the carrier detection of the CYP21 gene deficiency. Our results indicated that the rate of occurrence of the heterozygous CAH carrier was about 12 in 1,000, with a gene frequency of 0.0060 and an incidence frequency of 1 in 28,000 in the Chinese population. In addition, 9 cases of CAH families were performed with prenatal diagnosis. Among them, 3 cases were diagnosed as the severe form, 4 cases carried the heterozygous mutation, and 2 were normal. This is the first report of carrier frequency analysis and prenatal diagnosis of 21-hydroxylase deficiency in Chinese.


Assuntos
Hiperplasia Suprarrenal Congênita , Hiperplasia Suprarrenal Congênita/diagnóstico , Hiperplasia Suprarrenal Congênita/etiologia , Povo Asiático/genética , Triagem de Portadores Genéticos , Diagnóstico Pré-Natal , Hiperplasia Suprarrenal Congênita/etnologia , Hiperplasia Suprarrenal Congênita/genética , China , Feminino , Frequência do Gene , Testes Genéticos/métodos , Humanos , Masculino , Mutação , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Esteroide 21-Hidroxilase/genética
9.
Neurology ; 51(3): 878-9, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9748047

RESUMO

A Chinese male infant with arthrogryposis multiplex congenita (AMC), ventricular and atrial septal defects, and Werdnig-Hoffmann disease (WHD) had deletions of the telomeric copy of the survival motor neuron (SMN(T)) and neuronal apoptosis inhibitory protein genes. Children with AMC or congenital heart disease, or both, and motor neuron disease should undergo testing for SMN(T) deletion. This rare association further illustrates the variable phenotypic expressions of WHD.


Assuntos
Proteínas do Tecido Nervoso/genética , Atrofias Musculares Espinais da Infância/genética , Artrogripose/complicações , Artrogripose/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Deleção de Genes , Comunicação Interatrial/complicações , Comunicação Interatrial/genética , Comunicação Interventricular/complicações , Comunicação Interventricular/genética , Humanos , Recém-Nascido , Masculino , Proteína Inibidora de Apoptose Neuronal , Proteínas de Ligação a RNA , Proteínas do Complexo SMN , Atrofias Musculares Espinais da Infância/complicações
10.
Neurology ; 53(3): 642-3, 1999 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-10449138

RESUMO

The alpha-2 macroglobulin five-nucleotide deletion (A2M-2) allele frequency was not significantly higher in the AD group than the control group (0.062 versus 0.101, p > 0.1). The odds ratio for AD in individuals with the A2M-2 allele was 0.582 (95% CI, 0.25 to 1.40). These results do not support the association between A2M-2 and AD in the Chinese population, although the allele frequency of A2M-2 is lower than that found in the Caucasian population. Therefore, A2M-2 might not be a significant risk factor of AD among Taiwan Chinese.


Assuntos
Doença de Alzheimer/genética , Deleção de Genes , alfa-Macroglobulinas/genética , Idoso , Idoso de 80 Anos ou mais , Alelos , Feminino , Genótipo , Humanos , Masculino , Reação em Cadeia da Polimerase , Taiwan
11.
Eur J Cancer ; 35(2): 302-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10448275

RESUMO

A variety of studies suggest that tumour suppressor loci on chromosome 11p are important in various forms of human neoplasia. Recently, a gene located at the chromosome 11p 15.1-15.2 region called TSG101 was discovered and proposed as a candidate tumour suppressor gene in breast cancers. We evaluated the TSG101 gene in a panel of liver cancer cell lines and paired tumours and non-malignant tissues. In this study, four of the seven (57%) cell lines, eight of the 18 (44%) tumours and four of the 18 (22%) non-malignant liver tissues exhibited aberrant TSG101 transcripts by nested reverse transcription-polymerase chain reaction (RT-PCR) analysis. However, a normal-sized transcript without sequence abnormalities verified by single-stranded conformation polymorphism (SSCP) analysis was expressed at robust levels in all the cell lines and most of the tissue samples tested. In addition, Southern blot analysis could identify no genomic abnormalities of the gene. Our results suggest either that the TSG101 gene may not be involved in hepatocarcinogenesis or that it plays a role in the development and/or progress of hepatocellular carcinomas through an unusual mechanism.


Assuntos
Carcinoma Hepatocelular/genética , Proteínas de Ligação a DNA/genética , Neoplasias Hepáticas/genética , Fatores de Transcrição/genética , Transcrição Gênica , Adulto , Idoso , Idoso de 80 Anos ou mais , Southern Blotting , Complexos Endossomais de Distribuição Requeridos para Transporte , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Células Tumorais Cultivadas
12.
Eur J Cancer ; 35(4): 647-51, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10492641

RESUMO

The 10q23.3 gene PTEN (phosphatase and Tensin homologue deleted on chromosome 10) or MMAC1 (mutated in multiple advanced cancers 1) was recently reported to undergo frequent mutation, including mutations and deletions in multiple advanced cancers. This study showed that the aberrant transcripts of this gene are frequently found in cancers of the digestive tract, paired non-cancerous tissues and normal peripheral mononuclear cells. Sequence analysis of the aberrant transcripts revealed three types of deletions: (i) a deletion junction with a splicing-like donor or acceptor sequence; (ii) several-base homology near or between the donor acceptor site at the deletion junction; and (iii) deletion with insertion. From these results, it is suggested that aberrant transcripts of PTEN/MMAC1 found by nested reverse transcription-polymerase chain reaction are a common (or natural) phenomenon unrelated to oncogenesis. The mechanism producing these aberrant transcripts needs further investigation. Using single-strand conformation polymorphism and direct sequencing to analyse for small base changes of the genomic DNA of the PTEN/MMAC1 gene revealed no point mutations or small base changes.


Assuntos
Neoplasias do Colo/genética , Neoplasias Esofágicas/genética , Mutação/genética , Proteínas de Neoplasias/genética , Monoéster Fosfórico Hidrolases/genética , Neoplasias Gástricas/genética , Proteínas Supressoras de Tumor , Deleção de Genes , Humanos , Perda de Heterozigosidade , PTEN Fosfo-Hidrolase , Polimorfismo Conformacional de Fita Simples , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Biotechniques ; 22(3): 520-7, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9067032

RESUMO

A rapid and simple method, termed multiplex mutagenically separated PCR (MS-PCR), was developed to detect several molecular defects in the hemoglobin gene in one PCR. This technique, in which different-size allele-specific primers were used, specifically amplified both normal and mutant alleles of the globin gene in the same reaction. Subsequent gel electrophoresis showed at least one of the two allelic products at the same locus or two of the several allelic products of different loci and provided a within-assay quality control for the exclusion of false-negative results. In our study, the four most common beta-thalassemia mutations, together with four other common hemoglobin variants in Chinese, were tested. Using multiplex MS-PCR 6 to 12 primers were added simultaneously into one reaction tube to identify one to four mutations. Not only is this multiplex MS-PCR method reliable and non-isotopic, the results can be obtained in less than one working day.


Assuntos
Hemoglobinas/genética , Reação em Cadeia da Polimerase/métodos , Talassemia beta/diagnóstico , Alelos , Povo Asiático , Primers do DNA , Eletroforese em Gel de Ágar , Globinas/genética , Heterozigoto , Humanos , Mutação/genética , Taiwan , Talassemia beta/genética
14.
Cancer Lett ; 150(2): 201-4, 2000 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-10704743

RESUMO

The protein tyrosine kinase activity of c-src proto-oncogene product, pp60(c-src), is elevated in a number of human cancers, including colon cancer. Phosphorylation of human pp60(c-src) carboxy-terminal tyrosine 530 suppresses its kinase activity. A recent report suggested that the risk of colon cancer is higher for those who carry a C-->T transition mutation on codon 531 (Gln-531-->Amber-531) of src gene. This mutation caused a prematured translation termination and up-regulated the kinase activity. To examine whether this mutation could be a risk factor for colon carcinoma in the Chinese population, we used the same PCR-based assay to analyze src genotypes of 131 colon cancers and other various types of carcinoma. No mutation was detected in all specimens that were screened in this study. Thus, mutation at Gln-531 of src gene does not seem to be involved in the development of colon cancer in Chinese ethnicity.


Assuntos
Códon , Neoplasias do Colo/genética , Genes src , Mutação , China , Neoplasias do Colo/etnologia , Neoplasias do Colo/etiologia , Humanos , Reação em Cadeia da Polimerase , Proto-Oncogene Mas
15.
Int J Oncol ; 16(1): 75-80, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10601551

RESUMO

Aberrant transcripts of FHIT and TSG101 using nested RT-PCR were reported in many human tumours. The role of these aberrant transcripts in tumourigenesis is not clear. We, therefore, analyzed the aberrant transcripts of FHIT, TSG101 and PTEN/MMAC1 in peripheral mononuclear cells of normal individuals using nested RT-PCR to explore the role of these genes in cancer development. The results showed that there are at least five types of aberrant transcripts: type I is the deletion at junction located in-between normal exon and intron; type II has deletion of some bases and subsequent insertion of several bases in the deletion area; type III accommodates splicing donor or acceptor site-like sequence; type IV has homologous sequences near the deleted junction; and type V comprises the homologous sequences at the deletion junction. A normal healthy person can have more than one aberrant transcripts of FHIT, TSG101 and PTEN/MMAC1 genes. The size and the number of the transcripts vary and the diversity is unconstrained. It is not depended on the time, condition of the reaction, or the isolation method. From these results, we suggested that the aberrant transcripts of FHIT, TSG101 and PTEN/MMAC1 genes may be the imperfect products of splicesome which occur one in every thousands, ten thousands or more. As a result, these data implied no direct association between the aberrant transcripts and tumourigenesis.


Assuntos
Hidrolases Anidrido Ácido , Proteínas de Ligação a DNA/genética , Leucócitos Mononucleares/metabolismo , Proteínas de Neoplasias , Monoéster Fosfórico Hidrolases/genética , Proteínas/genética , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor , Adulto , Sequência de Bases , DNA/análise , Complexos Endossomais de Distribuição Requeridos para Transporte , Humanos , Dados de Sequência Molecular , PTEN Fosfo-Hidrolase , RNA Mensageiro/análise , RNA Mensageiro/genética , Valores de Referência , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Am J Clin Pathol ; 100(6): 686-9, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8249918

RESUMO

A rapid, simple, and nonradioactive method for diagnosing point mutations of c-K-ras oncogenes in gastroenterologic cancers is described. This method involved the selective amplification of DNA fragments from cancer tissues of surgical specimens with specific oligonucleotide primers, followed by digestion with restriction enzymes that recognized artificially created or naturally occurring restriction sites. To detect codon 12 mutations, an artificial Msp I site was created by introducing a single nucleotide mismatch into the 5' mutagenesis primer. Using a similar approach, an Hae III site was created to detect codon 13 mutations. Bal I and MBo II sites were used to detect codon 61 mutations. A total of 61 gastroenterologic cancer cases were studied. Of 35 cases of colorectal cancer, 7 showed mutations: 6 at codon 12 and 1 at codon 13. In 1 of 2 cases of cholangiocellular carcinoma, point mutation at codon 12 was found. One case of duodenal cancer showed point mutation at codon 12. No mutations were found in the cases of hepatocellular carcinoma (4), gastric cancer (12), esophageal cancer (3), or pancreatic cancer (2).


Assuntos
Neoplasias Gastrointestinais/genética , Genes ras/genética , Mutação/genética , Sequência de Aminoácidos , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Mapeamento por Restrição
17.
Int J Hematol ; 59(4): 267-72, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8086620

RESUMO

The mutations producing beta-thalassemia minor in 227 Taiwanese were studied using the method of naturally and amplified created restriction sites. beta-Thalassemia minor was caused by one beta-globin gene mutation in most of the cases (225/227); only a few cases were caused by two gene mutation (2/227). The most common type of mutation was frameshift codon 41/42 (-TCTT) (93/227), followed in descending order by the C-->T substitution at nucleotide 654 of IVS-2 (83/227), the nonsense mutation A--T at codon 17 (22/227), the A-->T mutation at position -28 of the promotor region (12/227), the frameshift codon 27/28 (+C) (6/227), the initial codon mutation (ATG-->AGG) (5/227), and one each of the codon 71/72 (+A), IVS-1 nt 1 (G-->T), IVS-1 3' end (TAG-->GAG), and nonsense codon 43. In the two cases of the two-gene mutation, one was the nt 654 mutation with Hb Kaohsiung and another one was frameshift codon 41/42 with Hb Meinung. The first four mutations accounted for more than 90% of the mutations. The C-->T substitution at the nt 654 of IVS-2 and initial codon mutation in our study had a higher incidence than in other Southeast Asia areas. Comparison of clinical data in different types of beta-thalassemia showed that there were higher MCV and MCH levels in beta (+)-thalassemia.


Assuntos
Globinas/genética , Talassemia beta/genética , Adolescente , Adulto , Idoso , Sequência de Bases , Humanos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase , Taiwan
18.
Int J Hematol ; 59(1): 1-8, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8161731

RESUMO

To characterize mutations rapidly in 43 patients with beta-thalassemia major in Taiwan, we utilized a method of natural and amplified created restriction site (ACRS) analysis for detection of beta-globin gene mutation. After analysis, eight different point mutations were found among 86 known chromosomes. IVS-2 nt 654 (C-->T), accounting for 40 of the 86 mutations with mutant beta-globin genes, is the most common mutation, followed by frameshift codons 41/42 (-TCTT) in 28 mutations, -28 mutation (A-->G) in 7 mutations, nonsense codon 17 (A-->T) in 5 mutations, frameshift codons 27/28 (insertion of C) in 2 mutations, IVS-1 nt 1 (G-->T) in 2 mutations, frameshift codons 71/72 (insertion of A) in 1 mutation, and IVS-1 3' end TAG-->GAG in 1 mutation. The first four mutations account for 80 of all 86 mutations of beta-thalassemia major in Taiwan. Furthermore, the beta-globin gene mutation was identified successfully in one chorionic villi biopsy for prenatal diagnosis and in specimen of blood from one patient who had received bone marrow transplantation (BMT). Complete diagnosis is possible in all of the Chinese families with beta-thalassemia in Taiwan, and the first trimester prenatal diagnosis can be achieved simply by using only 13 oligonucleotide primers and 10 restriction endonucleases. This non-radioactive assay was shown to be a rapid, sensitive, precise and safe method in detecting the mutations of beta-thalassemia in Taiwan.


Assuntos
Doenças Fetais/diagnóstico , Diagnóstico Pré-Natal , Talassemia beta/diagnóstico , Adolescente , Sequência de Aminoácidos , Criança , Pré-Escolar , Feminino , Doenças Fetais/genética , Humanos , Lactente , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Gravidez , Mapeamento por Restrição , Taiwan , Talassemia beta/genética
19.
Int J Hematol ; 56(2): 155-9, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1421177

RESUMO

We used the polymerase chain reaction (PCR) to amplify the breakpoint area of alpha-thalassemia-1 of Southeast Asia type and several parts of the alpha-globin gene cluster to make a differential diagnosis between alpha-thalassemia-1 and Hb Bart's hydrops fetalis. The procedure involved three primers to detect the homozygote of alpha-thalassemia-1, then amplifies the other alpha-globin gene cluster with three other pairs of primers to double check the results. The PCR products were checked again by allele specific probes. Twenty-two cases were diagnosed prenatally, two were normal, 17 were alpha-thalassemia-1, and three Hb Bart's hydrops fetalis. All cases were confirmed either by Southern blot hybridization or follow-up by sonography or after delivery. No false positive or false negative results were obtained by our strigent procedure. We conclude it to be a rapid, accurate and economic method.


Assuntos
Doenças Fetais/diagnóstico , Hemoglobinas Anormais/metabolismo , Hidropisia Fetal/diagnóstico , Diagnóstico Pré-Natal , Sudeste Asiático , Sequência de Bases , Diagnóstico Diferencial , Feminino , Hemoglobinas Anormais/genética , Humanos , Hidropisia Fetal/sangue , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Gravidez , Diagnóstico Pré-Natal/métodos , Talassemia alfa/diagnóstico
20.
Leuk Lymphoma ; 36(5-6): 463-6, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10784390

RESUMO

Tsg101 is a mouse tumor suppressor gene whose homozygous deletion produces transformation of NIH3T3 cells and leads to metastases in nude mice. The human homologue of the gene, TSG101, is localized in chromosome 11p15.1-p15.2. Reduced TSG101 expression may cause the defect of the cell cycle checkpoint that leads to genetic instability and consequently to the progression of neoplasia. Aberrant TSG101 transcript have been identified in many types of cancers, and the relaxation of RNA splicing fidelity may be an onco-developmental marker in cancers and could play a general role in tumorigenesis. In our previous study, smaller TSG101 transcripts were found in AML specimens, hematopoietic cell lines and normal controls. The aberrant transcripts occurred more frequently in the AML cases and cell lines. The patients with aberrant TSG101 transcripts had higher initial white cell count, lower LDH level, and lower complete remission rate after induction chemotherapy. However, further multivariate analysis of clinical data revealed that there was no relationship to the TSG101 aberrant transcripts. The clinical significance of TSG101 aberrant transcript in AML needs further evaluation.


Assuntos
Transformação Celular Neoplásica/genética , Proteínas de Ligação a DNA/genética , Leucemia Mieloide Aguda/genética , Fatores de Transcrição/genética , Células 3T3 , Animais , Complexos Endossomais de Distribuição Requeridos para Transporte , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Humanos , Leucemia Mieloide Aguda/etiologia , Leucemia Mieloide Aguda/patologia , Camundongos , Transcrição Gênica
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA