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1.
Knee ; 27(1): 26-35, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31917106

RESUMO

PURPOSE: Osteoarthritis (OA) of the knee is a multifactorial degenerative disease typically defined as the 'wear and tear' of articular joint cartilage. However, recent studies suggest that OA is a disease arising from chronic low-grade inflammation. We conducted a study to investigate the relationship between chronic inflammatory mediators present in both the systemic peripheral blood system and localised inflammation in synovial fluid (SF) of OA and non-OA knees; and subsequently made direct comparative analyses to understand the mechanisms that may underpin the processes involved in OA. METHODS: 20-Plex proteins were quantified using Human Magnetic Luminex® assay (R&D Systems, USA) from plasma and SF of OA (n = 14) and non-OA (n = 14) patients. Ingenuity Pathway Analysis (IPA) software was used to predict the relationship and possible interaction of molecules pertaining to OA. RESULTS: There were significant differences in plasma level for matrix metalloproteinase (MMP)-3, interleukin (IL)-27, IL-8, IL-4, tumour necrosis factor-alpha, MMP-1, IL-15, IL-21, IL-10, and IL-1 beta between the groups, as well as significant differences in SF level for IL-15, IL-8, vascular endothelial growth factor (VEGF), MMP-1, and IL-18. Our predictive OA model demonstrated that toll-like receptor (TLR) 2, macrophage migration inhibitory factor (MIF), TLR4 and IL-1 were the main regulators of IL-1B, IL-4, IL-8, IL-10, IL-15, IL-21, IL-27, MMP-1 and MMP-3 in the plasma system; whilst IL-1B, TLR4, IL-1, and basigin (BSG) were the regulators of IL-4, IL-8, IL-10, IL-15, IL-18, IL-21, IL-27, MMP-1, and MMP-3 in the SF system. CONCLUSION: The elevated plasma IL-8 and SF IL-18 may be associated with the pathogenesis of OA via the activation of MMP-3.


Assuntos
Cartilagem Articular/metabolismo , Interleucina-18/metabolismo , Interleucina-8/metabolismo , Articulação do Joelho/metabolismo , Osteoartrite do Joelho/metabolismo , Plasma/metabolismo , Líquido Sinovial/metabolismo , Idoso , Biomarcadores/metabolismo , Cartilagem Articular/patologia , Feminino , Humanos , Articulação do Joelho/patologia , Masculino , Osteoartrite do Joelho/patologia
2.
Clin Genet ; 90(4): 315-23, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26757417

RESUMO

Although an association between protein-truncating variants and breast cancer risk has been established for 11 genes, only alterations in BRCA1, BRCA2, TP53 and PALB2 have been reported in Asian populations. Given that the age of onset of breast cancer is lower in Asians, it is estimated that inherited predisposition to breast cancer may be more significant. To determine the potential utility of panel testing, we investigated the prevalence of germline alterations in 11 established and 4 likely breast cancer genes in a cross-sectional hospital-based cohort of 108 moderate to high-risk breast cancer patients using targeted next generation sequencing. Twenty patients (19%) were identified to carry deleterious mutations, of whom 13 (12%) were in the BRCA1 or BRCA2, 6 (6%) were in five other known breast cancer predisposition genes and 1 patient had a mutation in both BRCA2 and BARD1. Our study shows that BRCA1 and BRCA2 account for the majority of genetic predisposition to breast cancer in our cohort of Asian women. Although mutations in other known breast cancer genes are found, the functional significance and breast cancer risk have not yet been determined, thus limiting the clinical utility of panel testing in Asian populations.


Assuntos
Neoplasias da Mama/genética , Mutação em Linhagem Germinativa , Adulto , Proteína BRCA1/química , Proteína BRCA1/genética , Proteína BRCA2/química , Proteína BRCA2/genética , Estudos de Coortes , Estudos Transversais , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Malásia , Linhagem , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/genética , Ubiquitina-Proteína Ligases/química , Ubiquitina-Proteína Ligases/genética
3.
Clin Genet ; 88(5): 450-5, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25318593

RESUMO

Type of cancer and age of onset in individuals with inherited aberrations in the tumour suppressor gene TP53 are variable, possibly influenced by genetic modifiers and different environmental exposure. Since 2009, the modified Chompret criteria (MCC) have been used to identify individuals for TP53 mutation screening. Using the TP53 mutation database maintained by the International Agency for Research on Cancer (IARC), we investigated if the MCC, mainly developed for a Caucasian population, was also applicable in Asia. We identified several differences in Asian families compared with similar Caucasian cohorts, suggesting that identification and management of Li-Fraumeni syndrome in Asia do not completely mirror that of North America and Western Europe. Early gastric cancer (<40 years) may be considered a new addition to the MCC especially for Asian families.


Assuntos
Síndrome de Li-Fraumeni/complicações , Mutação , Neoplasias Gástricas/epidemiologia , Proteína Supressora de Tumor p53/genética , Povo Asiático/genética , Humanos , Neoplasias Gástricas/genética
5.
Med J Malaysia ; 69 Suppl A: 8-22, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25417947

RESUMO

Four hundred and nineteen articles related to breast cancer were found in a search through a database dedicated to indexing all original data relevant to medicine published in Malaysia between the years 2000-2013. One hundred and fifty four articles were selected and reviewed on the basis of clinical relevance and future research implications. Overall, Malaysian women have poor survival from breast cancer and it is estimated that half of the deaths due to breast cancer could be prevented. Five-year survival in Malaysia was low and varies among different institutions even within the same disease stage, suggesting an inequity of access to optimal treatment or a lack of compliance to optimal treatment. Malaysian women have poor knowledge of the risk factors, symptoms and methods for early detection of breast cancer, leading to late presentation. Moreover, Malaysian women experience cancer fatalism, belief in alternative medicine, and lack of autonomy in decision making resulting in delays in seeking or avoidance of evidence-based medicine. There are ethnic differences in estrogen receptor status, HER2 overexpression and incidence of triple negative breast cancer which warrant further investigation. Malay women present with larger tumours and at later stages, and even after adjustment for these and other prognostic factors (stage, pathology and treatment), Malay women have a poorer survival. Although the factors responsible for these ethnic differences have not been elucidated, it is thought that pharmacogenomics, lifestyle factors (such as weight-gain, diet and exercise), and psychosocial factors (such as acceptance of 2nd or 3rd line chemotherapy) may be responsible for the difference in survival. Notably, survivorship studies show self-management programmes and exercise improve quality of life, highlighting the need to evaluate the psychosocial impact of breast cancer on Malaysian women, and to design culturally-, religiously- and linguistically-appropriate psycho-education programmes to help women cope with the disease and improve their quality of life. Research done in the Caucasian populations may not necessarily apply to local settings and it is important to embark on local studies particularly prevention, screening, diagnostic, prognostic, therapeutic and psychosocial research.

6.
Br J Cancer ; 110(4): 1088-100, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24548884

RESUMO

BACKGROUND: Breast cancer is one of the most common malignancies in women. Genome-wide association studies have identified FGFR2 as a breast cancer susceptibility gene. Common variation in other fibroblast growth factor (FGF) receptors might also modify risk. We tested this hypothesis by studying genotyped single-nucleotide polymorphisms (SNPs) and imputed SNPs in FGFR1, FGFR3, FGFR4 and FGFRL1 in the Breast Cancer Association Consortium. METHODS: Data were combined from 49 studies, including 53 835 cases and 50 156 controls, of which 89 050 (46 450 cases and 42 600 controls) were of European ancestry, 12 893 (6269 cases and 6624 controls) of Asian and 2048 (1116 cases and 932 controls) of African ancestry. Associations with risk of breast cancer, overall and by disease sub-type, were assessed using unconditional logistic regression. RESULTS: Little evidence of association with breast cancer risk was observed for SNPs in the FGF receptor genes. The strongest evidence in European women was for rs743682 in FGFR3; the estimated per-allele odds ratio was 1.05 (95% confidence interval=1.02-1.09, P=0.0020), which is substantially lower than that observed for SNPs in FGFR2. CONCLUSION: Our results suggest that common variants in the other FGF receptors are not associated with risk of breast cancer to the degree observed for FGFR2.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Estudos de Casos e Controles , Feminino , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 5 de Fator de Crescimento de Fibroblastos/genética
7.
BJU Int ; 107(1): 28-39, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20840664

RESUMO

OBJECTIVE: To evaluate the role of targeted prostate cancer screening in men with BRCA1 or BRCA2 mutations, an international study, IMPACT (Identification of Men with a genetic predisposition to ProstAte Cancer: Targeted screening in BRCA1/2 mutation carriers and controls), was established. This is the first multicentre screening study targeted at men with a known genetic predisposition to prostate cancer. A preliminary analysis of the data is reported. PATIENTS AND METHODS: Men aged 40-69 years from families with BRCA1 or BRCA2 mutations were offered annual prostate specific antigen (PSA) testing, and those with PSA > 3 ng/mL, were offered a prostate biopsy. Controls were men age-matched (± 5 years) who were negative for the familial mutation. RESULTS: In total, 300 men were recruited (205 mutation carriers; 89 BRCA1, 116 BRCA2 and 95 controls) over 33 months. At the baseline screen (year 1), 7.0% (21/300) underwent a prostate biopsy. Prostate cancer was diagnosed in ten individuals, a prevalence of 3.3%. The positive predictive value of PSA screening in this cohort was 47·6% (10/21). One prostate cancer was diagnosed at year 2. Of the 11 prostate cancers diagnosed, nine were in mutation carriers, two in controls, and eight were clinically significant. CONCLUSIONS: The present study shows that the positive predictive value of PSA screening in BRCA mutation carriers is high and that screening detects clinically significant prostate cancer. These results support the rationale for continued screening in such men.


Assuntos
Detecção Precoce de Câncer/métodos , Genes BRCA1 , Genes BRCA2 , Predisposição Genética para Doença/genética , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico , Adulto , Idoso , Detecção Precoce de Câncer/normas , Métodos Epidemiológicos , Predisposição Genética para Doença/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Neoplasias da Próstata/sangue , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/genética
8.
Oral Oncol ; 46(5): 379-86, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20371203

RESUMO

Despite the advances in cancer treatment, the 5-year survival rate for oral cancer has not changed significantly for the past 40 years and still remains among the worst of all anatomic sites. Gene expression microarrays have been used successfully in the identification of genetic alterations in cancer development, however, these have hitherto been limited by the need for specimens with good quality intact RNA. Here, we demonstrated the use of formalin-fixed paraffin-embedded tissues in microarray experiments to identify genes differentially expressed between cancerous and normal oral tissues. Forty-three tissue samples were macrodissected and gene expression analyses were conducted using the Illumina DASL assay. We report RNA yield of 2.4 and 0.8 microg/mm(3) from tumour and normal tissues, respectively and this correlated directly with the tissue volume used for RNA extraction. Using unsupervised hierarchical clustering, distinct gene expression profiles for tumour and normal samples could be generated, and differentially expressed genes could be identified. The majority of these genes were involved in regulation of apoptosis and cell cycle, metastasis and cell adhesion including BCL2A1, BIRC5, MMP1, MMP9 and ITGB4. Representative genes were further validated in independent samples suggesting that these genes may be directly associated with oral cancer development. The ability to conduct microarrays on formalin-fixed paraffin-embedded specimens represents a significant advancement that could open up avenues for finding genes that could be used as prognostication and predictive tools for cancer.


Assuntos
Carcinoma de Células Escamosas/genética , Perfilação da Expressão Gênica/métodos , Neoplasias Bucais/genética , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Formaldeído , Regulação Neoplásica da Expressão Gênica , Humanos , Boca/citologia , Neoplasias Bucais/mortalidade , Neoplasias Bucais/patologia , Inclusão em Parafina , RNA Neoplásico/genética
9.
World J Surg ; 33(10): 2077-81, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19649760

RESUMO

BACKGROUND: Mutations in BRCA1 and BRCA2 confer an increased risk to breast and other cancers, but to date there have only been limited numbers of studies of BRCA1- and BRCA2-associated cancers among Asians. Malaysia is a multiracial country with three main races: Malays, Chinese, Indians. We determined whether tumor pathologic features and clinical features differ in patients with and without BRCA mutations in this Asian population. METHODS: We conducted a retrospective review of the medical records of 152 women with breast cancer who underwent genetic testing for BRCA mutations. The patients self-reported ethnicity, age at onset, and clinical stage at diagnosis and tumor pathology were reviewed. RESULTS: A total of 31 patients carried germline deleterious mutations (16 BRCA1, 15 BRCA2). We found that tumors in BRCA1 carriers were more likely to be estrogen receptor (ER)-negative and progesterone receptor (PR)-negative. HER2 was more likely to be negative in both BRCA1 and BRCA2 subjects compared with non-BRCA subjects. We found a strong association between triple-negative status and BRCA1 carriers. In addition, tumors in BRCA1 carriers were more likely to be higher grade than those in BRCA2 and non-BRCA carriers; but the difference was not statistically significant. CONCLUSIONS: These results suggest that tumors associated with BRCA1 mutations are distinct from those of BRCA2-associated and non-BRCA-associated breast cancers, and that the tumors associated with BRCA2 mutations are similar to the non-BRCA-associated breast cancers. Further studies are required to determine if the prognosis is different in each of these groups and the best management strategy for each group.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Países em Desenvolvimento , Genes BRCA1 , Genes BRCA2 , Adulto , Neoplasias da Mama/patologia , Feminino , Humanos , Malásia , Pessoa de Meia-Idade , Grupos Raciais , Estudos Retrospectivos
10.
Asian Pac J Cancer Prev ; 10(3): 395-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19640180

RESUMO

INTRODUCTION: Triple negative (TN) breast cancers are defined by a lack of expression of oestrogen, progesterone, and HER2 receptors. They tend to have a higher grade, with a poorer outcome compared to non-TN breast cancers. OBJECTIVE: The aim of this study is to determine the incidence of TN breast cancer in an Asian country consisting of Malays, Chinese and Indians, and to determine the factors associated with this type of breast cancer. RESULTS: The incidence of TN breast cancer in the University Malaya Medical Center is 17.6%. There is no significant difference amongst the Malays, Chinese and Indians. In bivariate analysis, TN breast cancer was significantly associated with younger age and Grade 3. However, in multivariate analysis using logistic regression, TN breast cancer was only associated with Grade 3. CONCLUSION: The incidence of TN breast cancer in our study is similar to other studies, and associated with a higher grade.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Feminino , Humanos , Malásia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Adulto Jovem
11.
Oral Oncol ; 45(8): 712-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19147396

RESUMO

Oral squamous cell carcinoma (OSCC) is a world health problem and is associated with exposure to different risk factors. In the west, smoking and alcohol consumption are considered to be the main risk factors whilst in India and southeast Asia, betel quid (BQ) chewing is predominant. In this study, we compared the gene expression patterns of oral cancers associated with BQ chewing to those caused by smoking using Affymetrix microarrays. We found that 281 genes were differentially expressed between OSCC and normal oral mucosa regardless of aetiological factors including MMP1, PLAU, MAGE-D4, GNA12, IFITM3 and NMU. Further, we identified 168 genes that were differentially expressed between the BQ and smoking groups including CXCL-9, TMPRSS2, CA12 and RNF24. The expression of these genes was validated using qPCR using independent tissue samples. The results demonstrate that whilst common genes/pathways contribute to the development of oral cancer, there are also other gene expression changes that are specific to certain risk factors. The findings suggest that different carcinogens activate or inhibit specific pathways during cancer development and progression. These unique gene expression profiles should be taken into consideration when developing biomarkers for future use in prognostic or therapeutic applications.


Assuntos
Areca/efeitos adversos , Carcinoma de Células Escamosas/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias Bucais/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/induzido quimicamente , Feminino , Perfilação da Expressão Gênica , Humanos , Malásia , Masculino , Análise em Microsséries , Pessoa de Meia-Idade , Neoplasias Bucais/induzido quimicamente , Reação em Cadeia da Polimerase , Fatores de Risco , Fumar/efeitos adversos
12.
Breast Cancer Res ; 10(4): R59, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18627636

RESUMO

INTRODUCTION: The cost of genetic testing and the limited knowledge about the BRCA1 and BRCA2 genes in different ethnic groups has limited its availability in medium- and low-resource countries, including Malaysia. In addition, the applicability of many risk-assessment tools, such as the Manchester Scoring System and BOADICEA (Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm) which were developed based on mutation rates observed primarily in Caucasian populations using data from multiplex families, and in populations where the rate of breast cancer is higher, has not been widely tested in Asia or in Asians living elsewhere. Here, we report the results of genetic testing for mutations in the BRCA1 or BRCA2 genes in a series of families with breast cancer in the multi-ethnic population (Malay, Chinese and Indian) of Malaysia. METHOD: A total of 187 breast cancer patients with either early-onset breast cancer (at age

Assuntos
Neoplasias da Mama/etnologia , Neoplasias da Mama/genética , Genes BRCA1 , Genes BRCA2 , Mutação , Adulto , Algoritmos , Neoplasias da Mama/epidemiologia , Análise Mutacional de DNA , Feminino , Deleção de Genes , Humanos , Incidência , Malásia , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/genética , Valor Preditivo dos Testes
13.
Cancer Chemother Pharmacol ; 58(1): 91-8, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16211395

RESUMO

PURPOSE: Given that p53 is a tumor suppressor that plays a central role in the cellular response to DNA damage and that more than 50% of all cancers have mutated p53, the wider utility of photodynamic therapy (PDT) in the treatment of cancer will depend on an understanding of whether p53 status modulates response to PDT. In this study, we investigated the photosensitivity of isogenic cell lines that differ only in their p53 status to PDT using hypericin as the photosensitizer. METHODS: Acute (MTT) and chronic (clonogenic) cytotoxic assays were performed on two osteosarcoma cell-lines (U2OS and U2OS+p53DD) that are isogenic except that the latter expresses dominant negative p53. The inducible expression of p53 was determined on western blots. Uptake of hypericin, cell cycle profile analysis, measurement of membrane phosphatidylserine externalization and changes in mitochondrial membrane potential were investigated using flow cytometry. RESULTS: Hypericin uptake was observed to be equivalent in U2OS and U2OS+p53DD cells. There were no significant differences in cell killing between these cell-lines in both the MTT and clonogenic assays (IC(50) of 0.4 microg/ml from MTT assay). p53 expression did not increase up to 24 h after PDT treatment in both cell lines. There were also no significant differences in the cell-cycle arrest profiles and timing of onset of apoptosis. CONCLUSIONS: Taken together, these results suggest that the status of p53 may not be important in PDT-mediated cell killing or induction of apoptosis. By extension, these results imply that PDT may be used with equal efficacy for the treatment of p53-positive and -negative tumors.


Assuntos
Perileno/análogos & derivados , Fotoquimioterapia , Radiossensibilizantes/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Antracenos , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Osteossarcoma/tratamento farmacológico , Osteossarcoma/metabolismo , Perileno/farmacocinética , Perileno/farmacologia , Radiossensibilizantes/farmacocinética
14.
Proc Natl Acad Sci U S A ; 96(20): 11134-9, 1999 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-10500142

RESUMO

The human neurodegenerative and cancer predisposition condition ataxia-telangiectasia is characterized at the cellular level by radiosensitivity, chromosomal instability, and impaired induction of ionizing radiation-induced cell cycle checkpoint controls. Recent work has revealed that the gene defective in ataxia-telangiectasia, termed ATM, encodes an approximately 350-kDa polypeptide, ATM, that is a member of the phosphatidylinositol 3-kinase family. We show that ATM binds DNA and exploit this to purify ATM to near homogeneity. Atomic force microscopy reveals that ATM exists in two populations, with sizes consistent with monomeric and tetrameric states. Atomic force microscopy analyses also show that ATM binds preferentially to DNA ends. This property is similar to that displayed by the DNA-dependent protein kinase catalytic subunit, a phosphatidylinositol 3-kinase family member that functions in DNA damage detection in conjunction with the DNA end-binding protein Ku. Furthermore, purified ATM contains a kinase activity that phosphorylates serine-15 of p53 in a DNA-stimulated manner. These results provide a biochemical assay system for ATM, support genetic data indicating distinct roles for DNA-dependent protein kinase and ATM, and suggest how ATM may signal the presence of DNA damage to p53 and other downstream effectors.


Assuntos
Ataxia Telangiectasia/genética , DNA/metabolismo , Proteínas Serina-Treonina Quinases , Proteínas/isolamento & purificação , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ciclo Celular , Dano ao DNA , Proteínas de Ligação a DNA , Células HeLa , Humanos , Microscopia de Força Atômica , Fosforilação , Proteínas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor
15.
Curr Biol ; 9(13): 699-702, 1999 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10395545

RESUMO

The major mechanism for the repair of DNA double-strand breaks (DSBs) in mammalian cells is non-homologous end-joining (NHEJ), a process that involves the DNA-dependent protein kinase [1] [2], XRCC4 and DNA ligase IV [3] [4] [5] [6]. Rodent cells and mice defective in these components are radiation-sensitive and defective in V(D)J-recombination, showing that NHEJ also functions to rejoin DSBs introduced during lymphocyte development [7] [8]. 180BR is a radiosensitive cell line defective in DSB repair, which was derived from a leukaemia patient who was highly sensitive to radiotherapy [9] [10] [11]. We have identified a mutation within a highly conserved motif encompassing the active site in DNA ligase IV from 180BR cells. The mutated protein is severely compromised in its ability to form a stable enzyme-adenylate complex, although residual activity can be detected at high ATP concentrations. Our results characterize the first patient with a defect in an NHEJ component and suggest that a significant defect in NHEJ that leads to pronounced radiosensitivity is compatible with normal human viability and does not cause any major immune dysfunction. The defect, however, may confer a predisposition to leukaemia.


Assuntos
DNA Ligases/genética , Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Tolerância a Radiação/genética , Animais , Western Blotting , Linhagem Celular Transformada , DNA Ligase Dependente de ATP , DNA Ligases/metabolismo , Reparo do DNA/genética , Proteína Quinase Ativada por DNA , Proteínas de Ligação a DNA/genética , Fibroblastos/efeitos da radiação , Humanos , Mutação , Proteínas Nucleares , Leucemia-Linfoma Linfoblástico de Células Precursoras/radioterapia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Coelhos , Radiação Ionizante , Análise de Sequência de DNA
16.
J Infect ; 36(3): 331-5, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9661949

RESUMO

Ecthyma gangrenosum is a characteristic skin lesion that is caused by Pseudomonas aeruginosa (P. aeruginosa) in the majority of cases. Systemic P. aeruginosa usually complicates debilitating conditions like leukaemia, burns and cystic fibrosis. We report a patient with underlying hypogammaglobulinemia who developed ecthyma gangrenosum secondary to P. aeruginosa septicaemia, which was potentially life-threatening. Recognition of the characteristic skin lesions with prompt initiation of appropriate antibiotics and intravenous immunoglobulins were life-saving. A review of the English literature reports three other cases of ecthyma gangrenosum in patients with underlying hypogammaglobulinemia.


Assuntos
Agamaglobulinemia/complicações , Ectima/complicações , Infecções por Pseudomonas/complicações , Criança , Gangrena/complicações , Humanos , Masculino
17.
Am J Med Genet ; 66(1): 21-4, 1996 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-8957505

RESUMO

We report the first attempt at prenatal diagnosis of the carnitine transporter defect in a fetus at high risk of having the disorder. Analysis of cultured CVS after prolonged culture predicted that the fetus was not affected but might be heterozygous for the carnitine transporter defect, but chromosome 15 satellite DNA markers showed no paternal contribution, suggesting that the CVS cells assayed were of predominantly maternal origin. Subsequent assay of cultured amniocytes predicted that the fetus would be affected, and this was confirmed in the newborn period. We conclude that prenatal diagnosis of the carnitine transporter defect is possible, but where results depend on extended culture of CVS, molecular studies should be performed to confirm genetic contributions from both parents.


Assuntos
Carnitina Aciltransferases/deficiência , Amostra da Vilosidade Coriônica , Erros Inatos do Metabolismo/diagnóstico , Carnitina/sangue , Carnitina Aciltransferases/genética , Feminino , Doenças Fetais/diagnóstico , Humanos , Masculino , Reação em Cadeia da Polimerase , Gravidez
18.
Ann Acad Med Singap ; 23(6): 814-8, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7741491

RESUMO

A retrospective study of 50 children newly diagnosed with acute lymphoblastic leukaemia (ALL) from December 1988 to November 1993 was carried out, examining the disease conditions and cytogenetic abnormalities. Of the 50 children, 8 had no cytogenetic examination of the marrow at the time of diagnosis and 7 had a poor yield from the marrow. Fifty percent of the remaining children had a normal karyotype. The rest of the children had hyperdiploidy and structural chromosomal abnormalities (mainly translocation and deletions) in equal proportions. Overall mortality of the whole group was about 26% with 2 lost to follow-up. There were 2 patients who relapsed while on treatment of whom 1 died. Cytogenetic abnormalities were correlated with clinical variables known to have prognostic significance. The group with hyperdiploidy had a significantly lower mean total white count at presentation and none of them died. The group with translocation abnormalities had a lower mean platelet count at presentation. Almost all in the group with hyperdiploidy and a great majority of the other 2 groups with normal or structural cytogenetic abnormalities were of B cell lineage. The median survival times for the hyperdiploid, normal karyotype and translocation patients were 1800 days, 1450 days and 700 days respectively.


Assuntos
Deleção Cromossômica , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocação Genética , Linfoma de Burkitt/genética , Linfoma de Burkitt/mortalidade , Pré-Escolar , Diploide , Feminino , Humanos , Cariotipagem , Leucemia-Linfoma de Células T do Adulto/genética , Leucemia-Linfoma de Células T do Adulto/mortalidade , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Estudos Retrospectivos , Taxa de Sobrevida
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