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1.
Environ Sci Technol ; 48(4): 2193-202, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24494622

RESUMO

Mercury (Hg) concentrations were monitored from 1999 to 2011 in largemouth bass (LMB) and yellow perch (YP) in 23 lakes in Massachusetts USA during a period of significant local and regional Hg emissions reductions. Average LMB tissue Hg concentration decreases of 44% were seen in 13 of 16 lakes in a regional Hg "hotspot" area. YP in all lakes sampled in this area decreased 43% after the major emissions reductions. Comparative decreases throughout the remainder of the state were 13% and 19% for LMB and YP respectively. Annual tissue mercury concentration rate decreases were 0.029 (LMB) and 0.016 mg Hg/kg/yr (YP) in the hotspot. In lakes around the rest of the state, LMB showed no trend and YP Hg decreased 0.0068 mg Hg/kg/yr. Mercury emissions from major point sources in the hotspot area decreased 98%, and 93% in the rest of the state from the early 1990s to 2008. The significant declines in fish Hg concentrations in many lakes occurred over the second half of a two decade decrease in Hg emissions primarily from municipal solid waste combustors and, secondarily, from other combustion point sources. In addition to the substantial Hg emissions reductions achieved in Massachusetts, further regional, national and global emissions reductions are needed for fish Hg levels to decrease below fish consumption advisory levels.


Assuntos
Bass/metabolismo , Monitoramento Ambiental , Água Doce/química , Mercúrio/análise , Percas/metabolismo , Poluentes Químicos da Água/análise , Animais , Geografia , Lagos/química , Massachusetts , Resíduos Sólidos , Fatores de Tempo
2.
J Thromb Haemost ; 20(10): 2323-2341, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35730241

RESUMO

BACKGROUND: Venous thromboembolism (VTE) is a prevalent disease with high morbidity and mortality. VTE has well-documented physical sequelae; however, the psychological and emotional impacts are seldom evaluated in randomized controlled trials. OBJECTIVE: We conducted a scoping review of published qualitative studies aiming to understand the physical, psychological, and emotional impact of VTE as reflected from patients' perspectives. This scoping review is part of a larger initiative to develop a core outcome set for VTE treatment studies. METHODS: A systematic literature search was conducted to identify qualitative studies assessing patient experience of VTE. Two authors independently screened titles and abstracts using Covidence systematic review software. Full-text reviews were conducted independently by 2 study team members. A modified method of "thematic synthesis" was used to collate themes upon reading and rereading of the publications. RESULTS: Our search strategy returned a total of 4944 citations; 28 were ultimately included in the analysis. The studies were conducted across 13 countries and representative of 436 participants including a spectrum of VTE subpopulations. There were seven major themes identified: Acute impacts: an unforeseen blow, Sustained psychological distress, Loss of self: life is changed, Challenges of thrombosis management, Balancing coping and control, Negative experience with the medical system, and VTE in the context of other conditions. CONCLUSIONS: The physical, psychological, and emotional impacts of VTE extend beyond objective outcomes typically evaluated in clinical trials. An improved understanding of the outcomes most important to patients will improve patient-centered care in VTE.


Assuntos
Tromboembolia Venosa , Trombose Venosa , Anticoagulantes/uso terapêutico , Humanos , Pesquisa Qualitativa , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/terapia , Trombose Venosa/tratamento farmacológico
3.
J Thromb Haemost ; 20(10): 2313-2322, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35717670

RESUMO

BACKGROUND: The development of a core outcome set (COS), defined as an agreed minimum set of outcome domains that should be measured and reported in all trials of a specific disease, aims to increase the relevance of study findings to stakeholder groups and improve standardization. OBJECTIVES: As the first step in developing a COS for venous thromboembolism (VTE) treatment studies, we aimed to generate an inclusive list of unique outcomes reported in previous VTE treatment studies and classify them into domains and core areas. METHODS: MEDLINE, Embase and CENTRAL were searched for prospective studies reporting on interventions for VTE in non-pregnant adults. Study selection and data extraction were performed in blocks based on publication date, starting with 2015-2020 and subsequent 1-year periods, until no new outcome was identified. Outcomes were classified into domains, which are groups of closely related outcomes, and domains into four core areas including death, pathophysiological manifestations/abnormalities, life impact, and resource use. RESULTS: Of 7100 records identified, 240 publications were included, representing 165 distinct studies. A total of 205 unique outcomes were identified that were grouped into 48 domains; 30 (13%) studies covered at least three core areas; death was included in 102 (43%), pathophysiological manifestations/abnormalities in 218 (91%), life impact in 41 (17%), and resource use in 25 (10%) studies. CONCLUSION: Most VTE treatment studies evaluated pathophysiological features of VTE, but few studies reported outcomes that measured life impact or resource use. The findings will inform next steps in the development of a COS for VTE treatment studies.


Assuntos
Tromboembolia Venosa , Adulto , Humanos , Estudos Prospectivos , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/tratamento farmacológico
4.
Mil Med ; 185(9-10): e1453-e1460, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32875318

RESUMO

INTRODUCTION: The emergence of Zika virus disease (ZVD) in areas of military operations provided a new opportunity for force health protection. ZVD infection had an estimated 4:1 asymptomatic-to-symptomatic ratio and can cause neurologic sequelae. MATERIALS AND METHODS: We provide a brief report of a field investigation utilizing laboratory-based surveillance and survey instruments to characterize ZVD risk among personnel deployed to the Dominican Republic in support of Operation NEW HORIZONS (NH). Additionally, we describe a cluster of 3 ZVD cases among 8 aircrew on a short mission to St. Croix (U.S. Virgin Islands). RESULTS: Following Operation NH, 6 of a total 189 deployed cohort members tested positive for ZVD by immunoglobulin M and confirmatory plaque reduction neutralization test (3.2%). Reverse transcription polymerase chain reaction testing in urine or serum was positive in 4 of those 6 cases. All 6 cases reported at least one symptom, with 5 reporting subjective fever and arthralgia and 4 reporting rash. Cases were less likely to have air-conditioned living quarters (odds ratio = 0.1; 95% confidence interval 0.02-0.77; P < 0.03), but were otherwise similar to non-cases. Likewise, in St. Croix, 3/8 tested positive by immunoglobulin M and plaque reduction neutralization test for an attack rate of 38%. Similar to Operation NH, all three cases were symptomatic with subjective fever (67%), arthralgia (67%), and/or rash (100%). CONCLUSIONS: This field investigation identified differing, mission location-dependent ZVD attack rates and a 0:9 asymptomatic-to-symptomatic case ratio. As this was unexpected based on a previous report of a 4:1 ratio, it emphasizes the need to be cautious before generalizing outbreak characteristics between populations while also offering additional practical experience for force health protection.


Assuntos
Militares , Saúde Pública , Infecção por Zika virus , Zika virus , Humanos , Serviços de Saúde Militar , Índias Ocidentais , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/epidemiologia
5.
BMJ Open ; 10(12): e040122, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33293309

RESUMO

INTRODUCTION: Venous thromboembolism (VTE) is a common, potentially fatal yet treatable disease. Several advances in treatment of VTE have been made over the past decades, but definition and reporting of outcomes across those studies are inconsistent. Development of an international core outcome set for clinical studies of interventions for VTE addresses this lack of standardisation. The first step in the development of a core outcome set is to conduct a scoping review which aims to generate an inclusive list of unique outcomes that have been reported in previous studies. METHODS AND ANALYSIS: MEDLINE, Embase and the Cochrane Central Register of Controlled Trials will be searched with no language restriction for prospective studies reporting on interventions for treatment of VTE in patients who are adult and non-pregnant. Records will be sorted in reverse chronological order. Study screening and data extraction will be independently performed by two authors in blocks based on date of publication, starting with 2015 to 2020 and subsequent 1-year periods, until no new outcome measures are identified from the set of included studies. After homogenising spelling and combining outcomes with the same meaning, a list of unique outcomes will be determined. Those outcomes will be grouped into outcome domains. Qualitative analysis and descriptive statistics will be used to report results. ETHICS AND DISSEMINATION: Ethical approval is not required for this study. The results of this scoping review will be presented at scientific conferences, published in a peer-reviewed journal, and they will provide candidate outcome domains to be considered in subsequent steps in the development of a core outcome set for clinical studies of interventions for VTE. PROTOCOL REGISTRATION DETAILS: http://hdl.handle.net/10393/40459.


Assuntos
Tromboembolia Venosa , Adulto , Feminino , Humanos , Avaliação de Resultados em Cuidados de Saúde , Gravidez , Estudos Prospectivos , Relatório de Pesquisa , Tromboembolia Venosa/tratamento farmacológico
7.
Acta Haematol ; 118(4): 237-41, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18160816

RESUMO

BACKGROUND/AIMS: To determine the molecular basis of a mild hemochromatosis phenotype in a man of Scottish-Irish descent. METHODS: We sequenced genomic DNA to detect mutations of HFE, SLC40A1, TFR2, HAMP, and HFE2. RNA isolated from blood mononuclear cells was used to make cDNA. RT-PCR was performed to amplify ferroportin from cDNA, and amplified products were visualized by electrophoresis and sequenced. RESULTS: The proband was heterozygous for the novel mutation c.1402G-->A (predicted G468S) in exon 7 of the ferroportin gene (SLC40A1). Located in the last nucleotide before the splice junction, this mutation results in aberrant splicing to a cryptic upstream splice site located at nt 990 within the same exon. This causes truncation of ferroportin after glycine 330 and the addition of 4 irrelevant amino acids before terminating. The truncated ferroportin protein, missing its C-terminal 241 amino acids, would lack all structural motifs beyond transmembrane region 7. The patient was also heterozygous for the common HFE H63D polymorphism, but did not have coding region mutations in TFR2, HAMP, or HFE2. CONCLUSIONS: We conclude that this patient represents a unique example of hemochromatosis due to a single base-pair mutation of SLC40A1 that results in aberrant splicing and truncation of ferroportin.


Assuntos
Substituição de Aminoácidos , Proteínas de Transporte de Cátions/genética , Hemocromatose/genética , Mutação Puntual , Sequência de Aminoácidos , Proteínas de Transporte de Cátions/química , Proteínas de Transporte de Cátions/deficiência , Sequência Conservada , Análise Mutacional de DNA , Éxons/genética , Genes Dominantes , Hemocromatose/terapia , Proteína da Hemocromatose , Heterozigoto , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Linhagem , Fenótipo , Flebotomia , Splicing de RNA
8.
J Negat Results Biomed ; 5: 5, 2006 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-16608528

RESUMO

Susceptibility to infection by bacterium such as Bacillus anthracis has a genetic basis in mice and may also have a genetic basis in humans. In the limited human cases of inhalation anthrax, studies suggest that not all individuals exposed to anthrax spores were infected, but rather, individuals with underlying lung disease, particularly asthma, sarcoidosis and tuberculosis, might be more susceptible. In this study, we determined if polymorphisms in genes important in innate immunity are associated with increased susceptibility to infectious and non-infectious lung diseases, particularly tuberculosis and sarcoidosis, respectively, and therefore might be a risk factor for inhalation anthrax. Examination of 45 non-synonymous polymorphisms in ten genes: p47phox (NCF1), p67phox (NCF2), p40phox (NCF4), p22phox (CYBA), gp91phox (CYBB), DUOX1, DUOX2, TLR2, TLR9 and alpha 1-antitrypsin (AAT) in a cohort of 95 lung disease individuals and 95 control individuals did not show an association of these polymorphisms with increased susceptibility to lung disease.


Assuntos
Pneumopatias/genética , Polimorfismo de Nucleotídeo Único , California/epidemiologia , Estudos de Coortes , Oxidases Duais , Flavoproteínas/genética , Predisposição Genética para Doença , Humanos , Glicoproteínas de Membrana/genética , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Infecções por Mycobacterium não Tuberculosas/genética , NADPH Oxidase 2 , NADPH Oxidases/genética , Fosfoproteínas/genética , Pneumonia/epidemiologia , Pneumonia/genética , Sarcoidose Pulmonar/epidemiologia , Sarcoidose Pulmonar/genética , Receptor 2 Toll-Like/genética , Receptor Toll-Like 9/genética , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/genética , População Branca/genética , alfa 1-Antitripsina/genética
9.
J Bone Joint Surg Am ; 84(1): 23-5, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11792775

RESUMO

BACKGROUND: Erythrocyte salvage, the collection of a patient's blood shed from the surgical wound, is one aspect of blood management. Previous investigators have examined salvaged blood for content; however, to our knowledge, none have examined the viability of erythrocytes after exposure to the chemical and thermal reactions produced by motorized instruments and polymethylmethacrylate during surgery. The purpose of this study was to determine the viability of salvaged erythrocytes from patients undergoing primary total joint arthroplasty with cement. METHODS: Erythrocyte viability studies were performed on specimens from three subjects with use of a double isotope-labeling technique employing chromium-51 and technetium-99m. With use of a fresh blood specimen obtained prior to surgery and a specimen of salvaged blood that had been recycled, washed, and filtered with use of the Cell Saver, the viability of the Cell-Saver-processed erythrocytes, labeled with chromium-51, was calculated on the basis of the technetium-99m-labeled red blood-cell mass. RESULTS: The mean erythrocyte viability (and standard deviation) in blood salvaged with use of the Cell Saver was 88.0% +/- 3.8%. The standard of the American Association of Blood Banks for minimum erythrocyte viability in adequately cross-matched allogeneic blood or predeposited autologous blood is 70%. CONCLUSIONS: The high rate of viability of the erythrocytes in this study shows that the Cell Saver is a valuable adjunct to other blood management techniques for patients having total joint arthroplasty. We believe that the very high mean rate of erythrocyte viability and the extremely small standard deviation in our three subjects, as compared with the standards of the American Association of Blood Banks, made additional study subjects unnecessary.


Assuntos
Artroplastia de Substituição , Transfusão de Sangue Autóloga , Envelhecimento Eritrocítico/fisiologia , Transfusão de Eritrócitos , Artroplastia de Substituição/métodos , Perda Sanguínea Cirúrgica , Cimentos Ósseos , Sobrevivência Celular/fisiologia , Humanos
10.
Isr Med Assoc J ; 4(11): 986-8, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12489486

RESUMO

BACKGROUND: Gaucher disease results from the accumulation of glucosylceramide (glucocerebroside) in tissues of affected persons. Patients sharing the same genotype present with widely varying degrees of lipid storage and of clinical manifestations. OBJECTIVES: To determine whether variation in the glucosylceramide synthase (UDPGlucose ceramide glucosyltransferase) gene, which encodes the enzyme that regulates the synthesis of glucocerebroside, could account for the variability and clinical manifestations. METHODS: Patients homozygous for the 1226G (N370S) mutation, the most common in the Ashkenazi Jewish population, were investigated. The exons and flanking sequences of the gene were sequenced using DNA derived from five very mild Gaucher disease patients and four patients with relatively severe Gaucher disease. RESULTS: One polymorphism was found in the coding region, but this did not change any amino acids. Seven other polymorphisms were found in introns and in the 5' untranslated region. Some of these were single nucleotide polymorphisms; others were insertions. The mutations appear to be in linkage equilibrium and none were found with a significantly higher frequency in either severe or mildly affected individuals. CONCLUSIONS: Mutations in the glucosylceramide synthase gene do not appear to account for the variability in expression of the common Jewish Gaucher disease mutation.


Assuntos
Doença de Gaucher/genética , Glucosiltransferases/genética , Judeus , Doença de Gaucher/classificação , Humanos , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo Genético , Índice de Gravidade de Doença
11.
Environ Health Perspect ; 118(1): 42-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20056583

RESUMO

OBJECTIVE: Perchlorate inhibits the uptake of iodide in the thyroid. Iodide is required to synthesize hormones critical to fetal and neonatal development. Many water supplies and foods are contaminated with perchlorate. Exposure standards are needed but controversial. Here we summarize the basis of the Massachusetts (MA) perchlorate reference dose (RfD) and drinking water standard (DWS), which are considerably lower and more health protective than related values derived by several other agencies. We also review information regarding perchlorate risk assessment and policy. DATA SOURCES: MA Department of Environmental Protection (DEP) scientists, with input from a science advisory committee, assessed a wide range of perchlorate risk and exposure information. Health outcomes associated with iodine insufficiency were considered, as were data on perchlorate in drinking water disinfectants. DATA SYNTHESIS: We used a weight-of-the-evidence approach to evaluate perchlorate risks, paying particular attention to sensitive life stages. A health protective RfD (0.07 microg/kg/day) was derived using an uncertainty factor approach with perchlorate-induced iodide uptake inhibition as the point of departure. The MA DWS (2 microg/L) was based on risk management decisions weighing information on perchlorate health risks and its presence in certain disinfectant solutions used to treat drinking water for pathogens. CONCLUSIONS: Current data indicate that perchlorate exposures attributable to drinking water in individuals at sensitive life stages should be minimized and support the MA DEP perchlorate RfD and DWS. Widespread exposure to perchlorate and other thyroid toxicants in drinking water and foods suggests that more comprehensive policies to reduce overall exposures and enhance iodine nutrition are needed.


Assuntos
Percloratos/normas , Percloratos/toxicidade , Poluentes Químicos da Água/normas , Poluentes Químicos da Água/toxicidade , Abastecimento de Água/normas , Conservação dos Recursos Naturais , Órgãos Governamentais , Humanos , Iodetos/metabolismo , Transporte de Íons/efeitos dos fármacos , Massachusetts , Percloratos/análise , Medição de Risco , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismo , Poluentes Químicos da Água/análise
12.
Blood Cells Mol Dis ; 22(1): 47, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12270286
13.
Blood Cells Mol Dis ; 39(2): 206-11, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17490902

RESUMO

The ferroportin polymorphism SLC40A1 Q248H (exon 6, cDNA 744G-->T; Gln248His) occurs in persons of sub-Saharan African descent with and without iron overload, and is associated with elevated serum ferritin concentrations (SF). However, the risk of iron overload associated with Q248H has not been defined. We tabulated previously reported Q248H allele frequency estimates in African-Americans and Native Africans, and computed the risk of iron overload associated with Q248H in subjects who lacked HFE C282Y. The aggregate Q248H allele frequency in 1038 African-Americans in two cohorts from Alabama and one cohort each from Washington, DC and California was 0.0525 (95% CI: 0.0451, 0.0652); there was no significant difference in frequencies across these cohorts. The aggregate frequency in 259 Natives from southeast Africa in two cohorts was 0.0946 (95% CI: 0.0694, 0.1198); the difference between the frequencies of these cohorts was not significant. The aggregate Q248H frequencies in African-Americans and Native Africans differed significantly (0.0525 vs. 0.0946, respectively; p=0.0021). There were reports of 24 unrelated African-Americans and 15 unrelated Native Africans without HFE C282Y who had iron overload. In African-Americans, the odds ratio (OR) of Q248H-associated risk of iron overload using 610 C282Y-negative control subjects unselected for SF was 1.57 (95% CI: 0.52, 4.72; p=0.29). In Native Africans, the OR using 208 control subjects unselected for SF was 1.05 (95% CI: 0.28, 3.90; p=0.58). We conclude that the frequency of SLC40A1 Q248H is significantly lower in African-Americans than in Native Africans. Although OR estimates of iron overload in African-Americans and Native Africans with Q248H were greater than unity, the increased OR were not statistically significant.


Assuntos
Negro ou Afro-Americano/genética , Proteínas de Transporte de Cátions/genética , Frequência do Gene , Sobrecarga de Ferro/etnologia , Sobrecarga de Ferro/genética , África Subsaariana/epidemiologia , Negro ou Afro-Americano/etnologia , Predisposição Genética para Doença/etnologia , Predisposição Genética para Doença/genética , Humanos , Epidemiologia Molecular
14.
Am J Hematol ; 81(10): 760-7, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16838333

RESUMO

We evaluated and treated four white adults (one man, three women) who had iron overload associated with daily ingestion of iron supplements for 7, 15, 35, and 61 years, respectively. We performed HFE mutation analysis to detect C282Y, H63D, and S65C in each patient; in two patients, HFE exons were sequenced. In two patients, direct sequencing was performed to detect coding region mutations of TFR2, HAMP, FPN1, HJV, and ALAS2. Patients 1-4 ingested 153, 547, 1,341, and 4,898 g of inorganic iron as supplements. Patient 1 had hemochromatosis, HFE C282Y homozygosity, and beta-thalassemia minor. Patient 2 had spherocytosis and no HFE coding region mutations. Patient 3 had no anemia, a normal HFE genotype, and no coding region mutations in HAMP, FPN1, HJV, or ALAS2; she was heterozygous for the TFR2 coding region mutation V583I (nt 1,747 G-->A, exon 15). Patient 4 had no anemia and no coding region mutations in HFE, TFR2, HAMP, FPN1, HJV, or ALAS2. Iron removed by phlebotomy was 32.4, 10.4, 15.2, and 4.0 g, respectively. There was a positive correlation of log(10) serum ferritin and the quantity of iron removed by phlebotomy (P = 0.0371). Estimated absorption of iron from supplements in patients 1-4 was 20.9%, 1.9%, 1.1%, and 0.08%. We conclude that the clinical phenotypes and hemochromatosis genotypes of adults who develop iron overload after ingesting iron supplements over long periods are heterogeneous. Therapeutic phlebotomy is feasible and effective, and would prevent complications of iron overload.


Assuntos
Suplementos Nutricionais/efeitos adversos , Hemocromatose/induzido quimicamente , Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Sobrecarga de Ferro/diagnóstico , Ferro/efeitos adversos , Proteínas de Membrana/genética , Adulto , Idoso , Esquema de Medicação , Feminino , Genótipo , Hemocromatose/diagnóstico , Proteína da Hemocromatose , Humanos , Ferro/administração & dosagem , Sobrecarga de Ferro/induzido quimicamente , Sobrecarga de Ferro/genética , Masculino , Mutação
15.
Blood ; 106(2): 740-5, 2005 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15790781

RESUMO

The average results of some laboratory measurements, including the hemoglobin, mean corpuscular volume (MCV), serum transferrin saturation (TS), serum ferritin, and white blood cell count of African-Americans differ from those of whites. Anonymized samples and laboratory data from 1491 African-American and 31 005 white subjects, approximately equally divided between men and women, were analyzed. The hematocrit, hemoglobin, MCV, TS, and white blood cell counts of African-Americans were lower than those of whites; serum ferritin levels were higher. When iron-deficient patients were eliminated from consideration the differences in hematocrit, hemoglobin, and MCV among women were slightly less. The -3.7-kilobase alpha-thalassemia deletion accounted for about one third of the difference in the hemoglobin levels of African-Americans and whites and neither sickle trait nor elevated creatinine levels had an effect. Among all subjects, 19.8% of African-American women would have been classified as "anemic" compared with 5.3% of whites. Among men, the figures were 17.7% and 7.6%. Without iron-deficient or thalassemic subjects, the difference had narrowed to 6.1% and 2.77% and to 4.29% and 3.6%, respectively. Physicians need to take into account that the same reference standards for hemoglobin, hematocrit, MCV, and TS and the white blood cell count do not apply to all ethnic groups.


Assuntos
População Negra , Hemoglobinas/metabolismo , Deficiências de Ferro , População Branca , Talassemia alfa/sangue , População Negra/genética , Estudos de Casos e Controles , Índices de Eritrócitos , Feminino , Frequência do Gene , Genótipo , Hemoglobina H/genética , Humanos , Ferro/sangue , Masculino , Pessoa de Meia-Idade , Fenótipo , Deleção de Sequência , Traço Falciforme/sangue , Traço Falciforme/genética , População Branca/genética , Talassemia alfa/genética
16.
Blood Cells Mol Dis ; 34(2): 157-61, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15727899

RESUMO

Hereditary hemochromatosis is a common disorder of iron metabolism most frequently associated with mutations in the HFE gene. Hereditary hemochromatosis may be caused by other less common genetic mutations including those in the ferroportin gene. Whereas hereditary hemochromatosis associated with HFE mutations is an autosomal recessive disorder, essentially all cases of hereditary hemochromatosis associated with ferroportin mutations follow an autosomal dominant pattern of inheritance, and most cases are notable for the lack of an elevated transferrin saturation and presence of iron deposition in Kupffer cells. This report describes the clinical and laboratory features of a family with hereditary hemochromatosis associated with a previously unrecognized ferroportin mutation (Cys326Ser). Three generations of the family are described. The disease in this family is notable for young age at onset, elevated transferrin saturation values, and hepatocyte iron deposition. The distinct molecular and clinical features reflect the heterogeneous nature of this disease.


Assuntos
Proteínas de Transporte de Cátions/genética , Hemocromatose/genética , Mutação de Sentido Incorreto , Adolescente , Adulto , Substituição de Aminoácidos , Criança , Feminino , Genes Dominantes , Humanos , Masculino , Linhagem
17.
Blood Cells Mol Dis ; 28(2): 191-5, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12064915

RESUMO

We have discovered two single-nucleotide polymorphisms in the 5' flanking region of the HFE gene. These mutations are -970 T-->G and -467 C-->G, numbering from the ATG start codon. When a T was present at -970, a C was always found at -467. The C allele was the less common at nt -467 with a gene frequency of 0.31 in white subjects with wild-type HFE. Slightly lower gene frequencies were observed in a small number of Hispanic and African-American subjects and a slightly higher frequency in a few Asian subjects. The less common -467 mutation was found in almost 12 chromosomes that bore the 845G-->A (C282Y) mutation and was significantly more prevalent in chromosomes containing the 187C-->G (H63D) mutation. Although this mutation is near an HNF3B/HFH2 site, its presence did not seem to affect iron metabolism as judged by the serum ferritin or transferrin saturation levels. The tighter association of the -467 polymorphism with the C282Y mutation is consistent with other data that suggest that the C282Y mutation has occurred relatively recently and that the H63D mutation is considerably older.


Assuntos
Região 5'-Flanqueadora/genética , Antígenos de Histocompatibilidade Classe I/genética , Proteínas de Membrana/genética , Polimorfismo de Nucleotídeo Único , Análise Mutacional de DNA , Etnicidade/genética , Evolução Molecular , Ferritinas/sangue , Frequência do Gene , Testes Genéticos , Proteína da Hemocromatose , Humanos , Distúrbios do Metabolismo do Ferro/epidemiologia , Distúrbios do Metabolismo do Ferro/genética , Mutação Puntual , Transferrina/metabolismo
18.
J Lab Clin Med ; 144(2): 65-8, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15322500

RESUMO

Patients with Gaucher disease have a deficiency of the lysosomal acid beta-glucosidase. The phenotypes of genotypically identical patients with Gaucher disease may differ markedly. We have examined the possibility that polymorphisms in another beta-glucosidase are responsible for this variability in the phenotype. Sequence analysis of the gene encoding cytosolic beta-glucosidase (GBA3) from 4 chromosomes revealed the presence of 4 single-nucleotide substitutions: c.316 G -->A (D106N), c.1353A-->G (Y451Y), c.1368T-->A (Y456X), and c.1540 to 1541AG -->T in the 3' untranslated region. We examined the DNA from 62 patients with Gaucher disease who were homozygous for the 1226A-->G (N370S) mutation and from 542 control subjects from various populations for these polymorphisms. Six of the possible 16 haplotypes were found, and none was over- or underrepresented among patients with the severe Gaucher disease phenotypes compared with those from patients with mild phenotypes.


Assuntos
Doença de Gaucher/genética , Mutação/genética , Polimorfismo de Nucleotídeo Único/genética , beta-Glucosidase/genética , Sequência de Bases , DNA/sangue , DNA/genética , Primers do DNA , Doença de Gaucher/enzimologia , Genótipo , Homozigoto , Humanos , Fenótipo , Reação em Cadeia da Polimerase
19.
Mov Disord ; 17(6): 1302-4, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12465072

RESUMO

Mice with targeted disruptions in the iron-responsive binding protein 2 (IRP2) gene accumulate iron in distinct regions of the brain and develop neurodegenerative characteristics resembling Parkinson's disease after 6 months of age. To determine whether polymorphisms in IRP2 predispose humans to Parkinson's disease (PD), we sequenced the IRP2 gene of subjects with sporadic PD and normal controls. Three polymorphisms which result in an amino acid change were identified: L159V, F272L, and T560I. The L159V and T560I polymorphisms, identified in an African-American PD subject, were found in the African-American population at an allele frequency of 0.102 (n = 1,236) and 0.111 (n = 1,228), respectively, and were not associated with an increased prevalence of PD. The F272L polymorphism was found in a normal 58-year-old, Caucasian subject whose father had PD, but it was not observed in 38 additional patients with sporadic PD. The F272L polymorphism occurred at an allele frequency of 0.0014 (n = 1,384) in the normal Caucasian population. Additional F272L heterozygous subjects identified in the normal population did not have a family or personal history of PD. We conclude that these IRP2 polymorphisms do not play an important role in the development of sporadic cases of PD. It remains to be determined whether other polymorphisms in IRP2 play a role in familial PD.


Assuntos
Proteína 2 Reguladora do Ferro/genética , Doença de Parkinson/genética , Polimorfismo Genético/genética , Idoso , Alelos , População Negra/genética , Cromossomos Humanos Par 15 , Análise Mutacional de DNA , Éxons , Feminino , Frequência do Gene/genética , Triagem de Portadores Genéticos , Genética Populacional , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA , População Branca/genética
20.
Blood Cells Mol Dis ; 29(3): 471-87, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12547238

RESUMO

Hereditary hemochromatosis is characterized by marked variation of expression of the defect: very few homozygotes with the C282Y/C282Y HFE genotype have full-blown clinical disease, a larger number show biochemical stigmata of iron overload, and some seem normal biochemically. The following candidate genes have been examined in detail to determine whether polymorphisms in them may be responsible for this variation: transferrin, transferrin receptor 1, transferrin receptor 2, ferritin-L, ferritin-H, IRP1, IRP2, HFE, beta(2) microglobulin, mobilferrin/calreticulin, ceruloplasmin, ferroportin, NRAMP1, NRAMP2 (DMT1), haptoglobin, heme oxygenase-1, heme oxygenase-2, hepcidin, USF2, ZIRTL, duodenal cytochrome b ferric reductase (DCYTB), TNFalpha, keratin 8, and keratin 18. The coding sequence, exon-intron junctions, and promoters of each of these genes was sequenced in DNA from 20 subjects: 5 HFE C282Y/C282Y with clinical disease, 5 HFE C282Y/C282Y with normal/low ferritin levels and no disease, 5 wt/wt with high ferritin and transferrin saturation, and 5 wt/wt normal controls. When coding or promoter polymorphisms were encountered, DNA from large numbers of ethnically defined subjects was examined for these polymorphisms and a relationship between their existence and abnormalities of iron homeostasis was sought. Only in the case of one transferrin mutation did we find a strong relationship between the polymorphism and iron deficiency anemia. The putative genes that affect the expression of HFE mutations remain elusive.


Assuntos
Homeostase/genética , Ferro/metabolismo , Mutação , Substituição de Aminoácidos , Proteína da Hemocromatose , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Proteínas de Membrana/genética , Polimorfismo Genético
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