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1.
Anal Biochem ; 669: 115113, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36958511

RESUMO

The aim of this guideline is to provide a series of evidence-based recommendations that allow those new to using MEGA-PRESS to produce high-quality data for the measurement of GABA levels using edited magnetic resonance spectroscopy with the MEGA-PRESS sequence at 3T. GABA is the main inhibitory neurotransmitter of the central nervous system and has been increasingly studied due to its relevance in many clinical disorders of the central nervous system. MEGA-PRESS is the most widely used method for quantification of GABA at 3T, but is technically challenging and operates at a low signal-to-noise ratio. Therefore, the acquisition of high-quality MRS data relies on avoiding numerous pitfalls and observing important caveats. The guideline was developed by a working party that consisted of experts in MRS and experts in guideline development and implementation, together with key stakeholders. Strictly following a translational framework, we first identified evidence using a systematically conducted scoping literature review, then synthesized and graded the quality of evidence that formed recommendations. These recommendations were then sent to a panel of 21 world leaders in MRS for feedback and approval using a modified-Delphi process across two rounds. The final guideline consists of 23 recommendations across six domains essential for GABA MRS acquisition (Parameters, Practicalities, Data acquisition, Confounders, Quality/reporting, Post-processing). Overall, 78% of recommendations were formed from high-quality evidence, and 91% received agreement from over 80% of the expert panel. These 23 expert-reviewed recommendations and accompanying extended documentation form a readily useable guideline to allow those new to using MEGA-PRESS to design appropriate MEGA-PRESS study protocols and generate high-quality data.


Assuntos
Encéfalo , Ácido gama-Aminobutírico , Espectroscopia de Ressonância Magnética/métodos , Razão Sinal-Ruído , Sistema Nervoso Central
2.
Musculoskelet Sci Pract ; 64: 102745, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36924580

RESUMO

BACKGROUND: People with musculoskeletal conditions often seek care from physiotherapists. Some, particularly those at risk of poor outcomes, may benefit from referral to physiotherapists with expertise in managing musculoskeletal conditions and/or multidisciplinary care. Understanding referral practices of physiotherapists, and how experience influences those practices, may assist in implementing optimal care pathways in primary care. AIMS: Explore (i) current referral practices of recent graduate and experienced physiotherapists who manage musculoskeletal conditions; (ii) opinions about referral to specialist physiotherapists for people at risk of poor outcomes. METHODS: This qualitative study consisted of 23 semi-structured interviews with recent graduate (n = 9) and experienced physiotherapists (n = 14) working in primary care. Perspectives of participants' current referral practices (to whom, when and why they are referred) and referral to specialist physiotherapists were sought. Interviews were recorded and transcribed verbatim prior to analysis. RESULTS: Referral practices for both groups were influenced by specific diagnoses, complexity of presentations, confidence, self-awareness, the clinical environment and system-related factors. Experienced physiotherapists were more confident and specific in their referrals and had established trusted networks compared with new graduates. Early referral to specialist physiotherapists was more likely when therapists were co-located. Barriers to early referral were lack of awareness, health system factors and impact on the patient (e.g., financial, time, continuity of care). CONCLUSION: Understanding factors influencing referral decisions may improve both intra- and interprofessional care for people with musculoskeletal conditions. Referral of people at risk of poor outcomes to specialist physiotherapists may be improved by greater intraprofessional awareness and clarity of roles.


Assuntos
Fisioterapeutas , Encaminhamento e Consulta , Humanos , Doenças Musculoesqueléticas/terapia , Austrália , Pesquisa Qualitativa , Atenção Primária à Saúde
3.
S Afr Med J ; 111(1): 26-32, 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33404002

RESUMO

BACKGROUND: Prostate cancer (PCa) is the leading male neoplasm in South Africa (SA) and is the second most frequently diagnosed cancer among men globally. Age-specific incidence rates (ASIRs) vary by up to 189-fold globally, with an ASIR of 68.0 per 100 000 in 2018 in SA. OBJECTIVES: To describe PCa among men undergoing prostate biopsy in Gauteng Province, SA. METHODS: We undertook a retrospective descriptive study using prostate biopsy data collected from the National Health Laboratory Service (NHLS) database between 2006 and 2016. We extracted the Systematized Nomenclature of Medicine (SNOMED) clinical terms morphology and topography codes to assign histological findings using the International Classification of Diseases for Oncology. PCa was defined as adenocarcinoma with a reported Gleason Score (GS). The new grade group (GG) based on the GS is defined as follows; (i) GG1 for a GS ≤6; (ii) GG2 for a GS of 3 + 4 = 7 ; (iii) GG3 for a GS of 4 + 3 = 7; (iv) GG4 for a GS of 8; and (v) GG5 for a GS ≥9. Higher-grade disease was defined as GG4 and GG5 (GS ≥8), in line with local guidelines. We reported associations of PCa with a GS ≥7 with age and race and used provincial and world standard population data to determine annual ASIRs. RESULTS: We identified 22 937 biopsies referred to the NHLS between 2006 and 2016. Of the 6 448 biopsies (39%) with a PCa finding for black Africans, 46% were diagnosed with high-risk PCa compared with 36 - 40% for other race groups (p<0.0001). Black Africans were more likely than whites to have GG4 or GG5 PCa (odds ratio 1.45; 95% confidence interval 1.27 - 1.67). The ASIR increased from 44.9 per 100 000 in 2006 to 57.3 per 100 000 in 2016. CONCLUSIONS: Black African men were significantly more likely to present with PCa with a GS ≥8 (GG4 and GG5) compared with the other racial groups in Gauteng. The ASIR increased dramatically during the study period, perhaps as a result of increased screening and awareness. There is a need for additional research to better understand why black African men present with higher-grade disease.


Assuntos
Biópsia , Programas de Rastreamento/métodos , Neoplasias da Próstata/epidemiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Humanos , Incidência , Laboratórios , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Estudos Retrospectivos , África do Sul/epidemiologia
4.
Gynecol Oncol Rep ; 25: 65-69, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29928684

RESUMO

Eighty-five percent of the incidents and deaths from cervical cancer occur in low and middle income countries. In many of these countries, this is the most common cancer in women. The survivals of the women with gynecologic cancers are hampered by the paucity of prevention, screening, treatment facilities and gynecologic oncology providers. Increasing efforts dedicated to improving education and research in these countries have been provided by international organizations. We describe here the existing educational and research programs that are offered by major international organizations, the barriers and opportunities provided by these collaborations and hope to improve the outcomes of cervical cancer through these efforts.

5.
Aust Health Rev ; 37(5): 688-94, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24160566

RESUMO

OBJECTIVE: The primary objective of this study was to evaluate the effect of an online education program used to implement the Australian (New South Wales) whiplash guidelines with general practitioners (GP). The secondary aim was to identify factors associated with learning. METHODS: An online educational and evaluation activity was developed to reflect the key messages for GP from the Australian whiplash guidelines. The educational activity was hosted on the Royal Australian College of General Practitioners' website (www.gplearning.com.au) for a period of 3 years. Participants were recruited through advertisement and media releases. Participants completed a baseline evaluation of their knowledge, participated in the interactive educational activity and completed a post-knowledge questionnaire. The primary outcome was change in professional knowledge, predictors of learning were computed using linear regression. RESULTS: Two hundred and fifteen GP participated. Knowledge significantly improved between baseline and post-knowledge questionnaire scores (P < 0.00001). A total of 57.2% of participants improved their knowledge by more than 20%, indicating a large effect. Low baseline knowledge predicted learning, accounting for 71% of the variance. CONCLUSIONS: Online education of GP significantly improved their knowledge in relation to guidelines for whiplash. Those with low baseline knowledge improved their knowledge the most, suggesting that implementation strategies should be targeted at this group.


Assuntos
Instrução por Computador , Educação Médica Continuada/métodos , Clínicos Gerais , Fidelidade a Diretrizes , Guias de Prática Clínica como Assunto , Traumatismos em Chicotada/diagnóstico , Traumatismos em Chicotada/terapia , Avaliação Educacional , Feminino , Humanos , Masculino , New South Wales , Estudos Prospectivos , Inquéritos e Questionários
6.
Prostate Cancer Prostatic Dis ; 16(4): 308-14, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24061634

RESUMO

BACKGROUND: Men with a family history of prostate cancer and African-American men are at high risk for prostate cancer and in need of personalized risk estimates to inform screening decisions. This study evaluated genetic variants in genes encoding microRNA (miRNA) binding sites for informing of time to prostate cancer diagnosis among ethnically diverse, high-risk men undergoing prostate cancer screening. METHODS: The Prostate Cancer Risk Assessment Program (PRAP) is a longitudinal screening program for high-risk men. The eligibility includes men aged between 35 and 69 years with a family history of prostate cancer or African descent. Participants with 1 follow-up visit were included in the analyses (n=477). Genetic variants in genes encoding miRNA binding sites (ALOX15 (arachidonate 15-lipooxygenase), IL-16, IL-18 and RAF1 (v-raf-1 murine leukemia viral oncogene homolog 1)) previously implicated in prostate cancer development were evaluated. Genotyping methods included Taqman SNP Genotyping Assay or pyrosequencing. Cox models were used to assess time to prostate cancer diagnosis by risk genotype. RESULTS: Among 256 African Americans with one follow-up visit, the TT genotype at rs1131445 in IL-16 was significantly associated with earlier time to prostate cancer diagnosis vs the CC/CT genotypes (P=0.013), with a suggestive association after correction for false discovery (P=0.065). Hazard ratio after controlling for age and PSA for TT vs CC/CT among African Americans was 3.0 (95% confidence interval: 1.26-7.12). No association with time to diagnosis was detected among Caucasians by IL-16 genotype. No association with time to prostate cancer diagnosis was found for the other miRNA target genotypes. CONCLUSIONS: Genetic variation in IL-16 encoding miRNA target site may be informative of time to prostate cancer diagnosis among African-American men enrolled in prostate cancer risk assessment, which may inform individualized prostate cancer screening strategies in the future.


Assuntos
Negro ou Afro-Americano/genética , Variação Genética , Interleucina-16/genética , MicroRNAs/genética , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/genética , Interferência de RNA , Adulto , Idoso , Sítios de Ligação , Seguimentos , Humanos , Interleucina-16/metabolismo , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/mortalidade , Fatores de Risco
7.
Fam Cancer ; 11(1): 69-75, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21898151

RESUMO

Risk-reducing salpingo-oophorectomy (RRSO) significantly reduces the risk of ovarian cancer and breast cancer in pre-menopausal women with BRCA1 and BRCA2 (B1/2) mutations. Despite its clear benefits, little is known about non-cancer endpoints in this population. Medical records were examined in 226 B1/2 mutation carriers, who had previously undergone RRSO with a focus on bone health as well as the frequency of hypertension, hyperlipidemia, coronary artery disease (CAD), myocardial infarction (MI), diabetes, hypothyroidism and depression. From the medical records, DEXA scans, medications and medical conditions were recorded. Of the 226 patient records examined, 16% (36/226) had hypertension, 17% (39/226) hyperlipidemia, 2% (5/226) CAD or MI, 2% (4/226) diabetes, 13% (29/226) hypothyroidism and 14% (31/226) depression. DEXA results were available in 152 women. Of those DEXA scans, 71% (108/152) were abnormal (57% osteopenia and 14% osteoporosis). Among women who underwent RRSO prior to age 50, 71% (62/88) had osteopenia/osteoporosis. Although there was no difference in osteopenia/osteoporosis in women with RRSO prior to age 50 compared to those RRSO > 50, the age at follow up in these two groups differs greatly (mean age 44.7 vs. 60.6), suggesting that both current age and age at RRSO contribute to bone health assessment. In summary, here, we report the prevalence of non-cancer endpoints in a cohort of B1/2 mutation carriers and note a particularly high rate of osteopenia and osteoporosis in B1/2 with breast cancer undergoing RRSO prior to 50. Despite the risk reduction RRSO offers, attention should be paid to non-cancer endpoints, particularly bone health, in this population.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Doenças Ósseas Metabólicas/etiologia , Neoplasias da Mama/genética , Osteoporose/etiologia , Neoplasias Ovarianas/genética , Ovariectomia , Complicações Pós-Operatórias , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Ósseas Metabólicas/diagnóstico , Neoplasias da Mama/complicações , Neoplasias da Mama/cirurgia , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/etiologia , Depressão/diagnóstico , Depressão/etiologia , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/etiologia , Feminino , Seguimentos , Heterozigoto , Humanos , Hiperlipidemias/diagnóstico , Hiperlipidemias/etiologia , Hipertensão/diagnóstico , Hipertensão/etiologia , Hipotireoidismo/diagnóstico , Hipotireoidismo/etiologia , Prontuários Médicos , Pessoa de Meia-Idade , Mutação/genética , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/etiologia , Osteoporose/diagnóstico , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/cirurgia , Prognóstico , Estudos Retrospectivos , Comportamento de Redução do Risco
8.
Br J Cancer ; 104(8): 1356-61, 2011 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-21427728

RESUMO

BACKGROUND: Single-nucleotide polymorphisms (SNPs) in genes involved in DNA repair are good candidates to be tested as phenotypic modifiers for carriers of mutations in the high-risk susceptibility genes BRCA1 and BRCA2. The base excision repair (BER) pathway could be particularly interesting given the relation of synthetic lethality that exists between one of the components of the pathway, PARP1, and both BRCA1 and BRCA2. In this study, we have evaluated the XRCC1 gene that participates in the BER pathway, as phenotypic modifier of BRCA1 and BRCA2. METHODS: Three common SNPs in the gene, c.-77C>T (rs3213245) p.Arg280His (rs25489) and p.Gln399Arg (rs25487) were analysed in a series of 701 BRCA1 and 576 BRCA2 mutation carriers. RESULTS: An association was observed between p.Arg280His-rs25489 and breast cancer risk for BRCA2 mutation carriers, with rare homozygotes at increased risk relative to common homozygotes (hazard ratio: 22.3, 95% confidence interval: 14.3-34, P<0.001). This association was further tested in a second series of 4480 BRCA1 and 3016 BRCA2 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1 and BRCA2. CONCLUSIONS AND INTERPRETATION: No evidence of association was found when the larger series was analysed which lead us to conclude that none of the three SNPs are significant modifiers of breast cancer risk for mutation carriers.


Assuntos
Neoplasias da Mama/genética , Carcinoma/genética , Proteínas de Ligação a DNA/fisiologia , Epistasia Genética/fisiologia , Genes BRCA1 , Genes BRCA2 , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Carcinoma/epidemiologia , Proteínas de Ligação a DNA/genética , Feminino , Grupos Focais , Genes BRCA1/fisiologia , Genes BRCA2/fisiologia , Predisposição Genética para Doença , Heterozigoto , Humanos , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único , Proteína 1 Complementadora Cruzada de Reparo de Raio-X , Adulto Jovem
9.
J Urol ; 178(5): 1939-44; discussion 1945, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17868722

RESUMO

PURPOSE: The impact of body mass index on tumor characteristics and treatment failure in prostate cancer is not well understood in diverse ethnic groups. We evaluated the effect of body mass index in African-American and European American patients from a radical prostatectomy cohort between 1995 and 2004 with regard to tumor histopathological characteristics and biochemical relapse-free survival. MATERIALS AND METHODS: A total of 924 patients were studied to evaluate whether obese men (body mass index greater than 30) had different preoperative and postoperative tumor characteristics or biochemical relapse-free survival compared to nonobese men. There were 784 European American and 140 African-American patients analyzed using failure time models, adjusted for age, preoperative prostate specific antigen, tumor stage and race. RESULTS: Mean and median followup was 42 and 36 months, respectively. African-American men were significantly more obese than European American men. Mean body mass index was 29.0 in African-American and 28.1 in European American men (p = 0.003). African-American men (OR 2.30, 95% CI 1.04-5.1) were more likely to have higher tumor stage on final pathology. Obesity was a risk factor for biochemical failure in African-American men (adjusted hazard ratio 5.49, 95% CI 2.16-13.9) but not in European American men (HR 1.41, 95% CI 0.96-2.08), and this difference was statistically significant (p value for interaction 0.036). CONCLUSIONS: Obesity is associated with poorer tumor prognostic characteristics and decreased biochemical relapse-free survival, particularly in African-American men. These data suggest that obesity may in part explain the poorer prostate cancer prognosis seen in African-American men compared to other racial and ethnic groups.


Assuntos
Negro ou Afro-Americano , Obesidade/etnologia , Prostatectomia/métodos , Neoplasias da Próstata/etnologia , Índice de Massa Corporal , Intervalo Livre de Doença , Europa (Continente)/etnologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Razão de Chances , Prevalência , Prognóstico , Neoplasias da Próstata/complicações , Neoplasias da Próstata/terapia , Estudos Retrospectivos , Fatores de Risco , Falha de Tratamento , Estados Unidos/epidemiologia
10.
Am J Epidemiol ; 166(12): 1392-9, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17827444

RESUMO

Combined hormone replacement therapy (CHRT) containing estrogens and progestins is associated with breast cancer risk. The authors evaluated interactions between CHRT use and progestin metabolism genotypes at CYP3A4 and the progesterone receptor (PGR) and their effects on breast cancer risk using the population-based Women's Insights and Shared Experiences (WISE) Study (1999-2002) of postmenopausal Caucasian women (522 breast cancer cases, 708 controls). The authors observed an elevated risk of ductal tumors in women with 3 or more years of CHRT use and PGR 331A alleles compared with those who had neither factor (odds ratio = 3.35, 95% confidence interval (CI): 1.13, 9.99; two-sided p(interaction) = 0.035). They also observed an elevated risk of progesterone receptor-positive tumors in women who had had 3 or more years of CHRT use and PGR 331A alleles compared with those who had neither factor (odds ratio = 3.82, 95% CI: 1.26, 11.55; p = 0.028). Finally, they observed an increased risk of estrogen receptor-negative tumors in women without CHRT exposure and CYP3A4*1B alleles compared with those who had neither factor (odds ratio = 6.46, 95% CI: 2.02, 20.66; p = 0.024), although the biologic interpretation of this result requires further study. When stratified by recency of use, PGR effects were observed only in current CHRT users, while CYP3A4 effects were observed only in former CHRT users. Breast cancer risk in women who have used CHRT may be influenced by genetic factors involved in progestin metabolism.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Terapia de Reposição de Estrogênios , Farmacogenética , Pós-Menopausa , Idoso , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/metabolismo , Estudos de Casos e Controles , Terapia de Reposição de Estrogênios/efeitos adversos , Estrogênios/efeitos adversos , Estrogênios/uso terapêutico , Feminino , Genótipo , Humanos , Incidência , Modelos Logísticos , Pessoa de Meia-Idade , Pennsylvania/epidemiologia , Vigilância da População , Progesterona/efeitos adversos , Progesterona/uso terapêutico , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Sistema de Registros , Fatores de Risco , Fatores de Tempo , População Branca
11.
Inj Prev ; 12(2): 93-8, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16595423

RESUMO

OBJECTIVE: To define health outcomes of whiplash associated disorders (WAD) at three months, six months, and two years after injury and to examine predictors of these outcomes. DESIGN: Prospective cohort study. SETTING: New South Wales, Australia. SUBJECTS: People with compensable motor crash injuries who reported whiplash as one of their injuries. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Functional Rating Index (FRI), Short Form 36 (SF-36) at three months, six months, and two years after injury, ascertained by telephone interview. RESULTS: At three months, 33.6% of the cohort was recovered (as defined by FRI

Assuntos
Nível de Saúde , Qualidade de Vida , Traumatismos em Chicotada/epidemiologia , Adolescente , Adulto , Austrália/epidemiologia , Avaliação da Deficiência , Métodos Epidemiológicos , Feminino , Humanos , Revisão da Utilização de Seguros , Masculino , Pessoa de Meia-Idade , New South Wales/epidemiologia , Avaliação de Resultados em Cuidados de Saúde , Índice de Gravidade de Doença , Inquéritos e Questionários
12.
Int J Cancer ; 113(3): 471-4, 2005 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-15455347

RESUMO

Genetic factors may be used not only to assess risk of prostate cancer development but also to evaluate prostate cancer outcomes including clinical prognosis, treatment methods, and treatment response. To assess the role of family history on prostate cancer outcomes, we evaluated tumor characteristics, diagnostic precursors and biochemical (prostate specific antigen) relapse-free survival in men with and without a family history of prostate cancer. A total of 684 prostate cancer cases unselected for family history were identified from an ongoing hospital based prostate cancer case-control study between 1995 and 2002. Self-reported family history was grouped within the following categories: none, any, moderate (one affected first or second degree relative) and high (2 or more affected first or second degree relatives). We further considered groups defined by early (before age 60) and late (after age 60) age at diagnosis. Overall, tumor stage was not significantly associated with any (odds ratio [OR] = 1.43 95% confidence interval [CI] = 1.00-2.05) or moderate (OR = 1.48, 95% CI = 1.0-2.19) family histories. Men diagnosed before age 60, however, had higher tumor stages if they had any (OR = 2.19, 95% CI = 1.28-3.75) or moderate (OR = 2.15, 95% CI = 1.2-3.9) family histories. Men diagnosed after age 60 with any family history were significantly more likely to experience biochemical (PSA) failure (Hazard ratio [HR] = 2.60, 95%CI = 1.08-6.25). Men with any and moderate family histories were at significantly increased risk of biochemical failure (HR = 2.49, 95%CI = 1.25-4.95 and HR = 2.46, 95% CI = 1.17-5.16, respectively). Moderate family history increased probability of seminal vesicle invasion (OR = 2.14, 95%CI = 1.06-4.34). Our results suggest that a family history of prostate cancer may be associated with predictors of clinical outcome in prostate cancer cases unselected for a family history of prostate cancer.


Assuntos
Adenocarcinoma/genética , Neoplasias da Próstata/genética , Glândulas Seminais/patologia , Adenocarcinoma/secundário , Adenocarcinoma/terapia , Estudos de Casos e Controles , Humanos , Masculino , Anamnese , Pessoa de Meia-Idade , Invasividade Neoplásica , Próstata/metabolismo , Antígeno Prostático Específico , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Fatores de Risco , Taxa de Sobrevida , Resultado do Tratamento
14.
Environ Mol Mutagen ; 42(4): 299-305, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14673875

RESUMO

Numerous single nucleotide polymorphisms (SNPs) have been identified in the human genome, yet the functional significance of most is unknown. CYP3A4 is a key enzyme in the metabolism of numerous compounds. An A-->G substitution 290 bp upstream of the CYP3A4 transcription start site (CYP3A4*1B) has been associated with cancer phenotypes, but its phenotypic effects are unclear. To investigate the functional significance of CYP3A4*1B, we generated two luciferase reporter constructs: 1-kb (denoted L, long) and 0.5-kb (denoted S, short) promoter fragments containing either the variant (V(L),V(S)) or the wild-type (W(L), W(S)) sequences. We evaluated the effect of the variant sequence in the HepG2 and MCF-7 cell lines, and in primary human hepatocytes from three donors. Reporter constructs with the variant sequence had 1.2- to 1.9-fold higher luciferase activity than constructs with wild-type sequence in the cell lines (P < 0.0001) and hepatocytes (P = 0.021, P = 0.027, P = 0.061). The ratio of transcriptional activity for V(S):W(S) was similar to the V(L):W(L) ratio in HepG2 cells, but the V(S):W(S) ratio was consistently less than the V(L):W(L) ratio in MCF-7 cells. This suggests that CYP3A4 expression is higher from the variant promoter and that a repressor sequence may exist in the longer constructs. Electrophoretic mobility shift assays demonstrated specific binding of a component of HepG2 nuclear extract to both wild-type and variant promoters with consistently higher binding affinities to the wild-type sequence. This suggests the existence of a transcriptional repressor responsible for the lower CYP3A4*1A activity. Therefore, the phenotypic effects of the variant CYP3A4*1B may be associated with enhanced CYP3A4 expression due to reduced binding of a transcriptional repressor.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Transcrição Gênica , Linhagem Celular , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Citocromo P-450 CYP3A , Genes Reporter , Vetores Genéticos , Genoma Humano , Hepatócitos/metabolismo , Humanos , Luciferases/metabolismo , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Transfecção , beta-Galactosidase/metabolismo
15.
Hum Hered ; 55(4): 171-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14566095

RESUMO

Inherited polymorphisms in immuno-modulatory genes may contribute to variations in immune function and genetic susceptibility for complex diseases, including cancer. We report results from a comprehensive study to discover novel single nucleotide polymorphisms (SNPs) and to estimate allelic frequency for both novel and known coding and regulatory region SNPs in genes encoding proteins that have been implicated in the immune response to tumors. We identified 12 novel nucleotide substitution variants and one deletion variant in 17 genes analyzed (TGFBETA;R, BETA;2M, IFNGAMMA;, TNFALPHA;, TNFALPHA;R, LTALPHA;, IL-6, IL-12, IL-2, IL-1ALPHA;, IL-1BETA;, IL-1RN, IL-10, CTLA4, CD40L, FAS and FASL). We determined the frequency of these novel polymorphisms, as well as 17 previously identified polymorphisms, in a control sample of 158 individuals, approximately half of which were Caucasian (n = 74) and half of which were African American (n = 84). Significant differences in allele frequencies were observed between the two racial groups for 13/17 genes tested. These allelic variations maybe associated with alterations in immune function and thus susceptibility to a number of complex disease states such as cancer.


Assuntos
Citocinas/genética , Frequência do Gene , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Receptores Imunológicos/genética , Negro ou Afro-Americano , Feminino , Genética Populacional , Humanos , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , População Branca
16.
Urology ; 61(5): 987-92, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12736021

RESUMO

OBJECTIVES: To describe the clinical features of prostate cancer in Senegalese men and compare these features with those found in African-American and white American men. METHODS: We identified an unselected series of 121 patients with prostate cancer diagnosed at two hospitals in Dakar, Senegal between 1997 and 2002. Medical record abstractions were undertaken to evaluate the prostate tumor characteristics, patient age at diagnosis, prostate-specific antigen (PSA) levels, and reason for referral. In addition, these characteristics were compared with a sample of 455 U.S. white men and 60 African-American men with prostate cancer who were studied as part of a prostate cancer case-control study. RESULTS: Senegalese men had a significantly worse tumor stage than Americans (41.3% versus 18.8%, P <0.001), a significantly worse mean PSA level at diagnosis (mean PSA 72.7 ng/mL versus 9.0 ng/mL in Americans; P <0.001), and were diagnosed at a significantly later age than U.S. men (69 years versus 61 years, P <0.001). U.S. men were most likely to be diagnosed with prostate cancer after an elevated PSA test, and Senegalese men were most often diagnosed after presenting for prostate-related symptoms. CONCLUSIONS: These observations are not unexpected given the differences in the patterns of prostate cancer screening and health care in the United States compared with Senegal. However, our data provide descriptive information about the characteristics of prostate cancer diagnosed in Senegal and highlight differences in the characteristics and detection of these tumors across populations with very different healthcare systems.


Assuntos
Neoplasias da Próstata/etnologia , Neoplasias da Próstata/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , População Negra , Estudos de Casos e Controles , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/estatística & dados numéricos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico , Senegal/epidemiologia , Senegal/etnologia , População Branca
18.
Genetics ; 163(3): 1215-9, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12663557

RESUMO

Molecular epidemiological association studies use valuable biosamples and incur costs. Statistical methods for early genotyping termination may conserve biosamples and costs. Group sequential methods (GSM) allow early termination of studies on the basis of interim comparisons. Simulation studies evaluated the application of GSM using data from a case-control study of GST genotypes and prostate cancer. Group sequential boundaries (GSB) were defined in the EAST-2000 software and were evaluated for study termination when early evidence suggested that the null hypothesis of no association between genotype and disease was unlikely to be rejected. Early termination of GSTM1 genotyping, which demonstrated no association with prostate cancer, occurred in >90% of the simulated studies. On average, 36.4% of biosamples were saved from unnecessary genotyping. In contrast, for GSTT1, which demonstrated a positive association, inappropriate termination occurred in only 6.6%. GSM may provide significant cost and sample savings in molecular epidemiology studies.


Assuntos
Doenças Genéticas Inatas/epidemiologia , Doenças Genéticas Inatas/genética , Simulação por Computador , Marcadores Genéticos , Glutationa Transferase/genética , Humanos , Epidemiologia Molecular/métodos , Reprodutibilidade dos Testes , Tamanho da Amostra
20.
Hum Hered ; 54(1): 13-21, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12446983

RESUMO

OBJECTIVES: Ethnic differences in prostate cancer incidence are well documented, with African-Americans having among the highest rates in the world. Ethnic differences in genotypes for genes associated with androgen metabolism including SRD5A2 and CYP3A4 also may exist. The aim of this study was to evaluate differences in these genotypes by ethnicity. METHODS: We studied cancer-free controls representative of four groups: 147 African Americans, 410 Caucasian-Americans, 129 Ghanaians, and 178 Senegalese. PCR-based genotype analysis was undertaken to identify two alleles (V89L, A49T) at SRD5A2 and *1B allele at CYP3A4. RESULTS: Differences were observed for V89L (variant frequency of 30% in Caucasians, 27% in African Americans, 19% in Ghanaians, and 18% in Senegalese, p = 0.002) and were observed for CYP3A4*1B (variant frequencies of 8% in Caucasians, 59% in African Americans, 81% in Ghanaians, and 78% in Senegalese, p = 0.0001). Pooled data combining the present data and previously published data from from Asian, Hispanic, and Arab cancer-free controls showed significant ethnic differences for SRD5A2 and CYP3A4 polymorphisms. Overall, Asians were least likely to have alleles associated with increased prostate cancer risk, while Africans were most likely to have those alleles. CONCLUSIONS: These results suggest that ethnicity-specific differences in genotype frequencies exist for SRD5A2 and CYP3A4. Africans and African-Americans have the highest frequency of those alleles that have previously been associated with increased prostate cancer risk. Future studies should address whether allele frequency differences in part explain differences in prostate cancer incidence in these populations.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Predisposição Genética para Doença/genética , Oxirredutases/genética , Neoplasias da Próstata/genética , População Negra/genética , Colestenona 5 alfa-Redutase , Citocromo P-450 CYP3A , Feminino , Predisposição Genética para Doença/epidemiologia , Genótipo , Gana , Humanos , Masculino , Pessoa de Meia-Idade , Senegal , Estados Unidos , População Branca/genética
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