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2.
Chemosphere ; 337: 139374, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37394190

RESUMO

The present study aimed to evaluate the effectiveness of seagrass recolonization as a nature-based solution for the recovery of a coastal area historically contaminated by mercury (Laranjo Bay, Ria de Aveiro, Portugal). A mesocosm approach was employed to assess the resistance of Zostera noltei to transplantation into contaminated sediments collected in-situ (0.5-20 mg kg-1 Hg). At each sampling time (15, 30, 60, 120 and 210 days), the resistance of transplanted Z. noltei was evaluated through growth parameters (biomass and coverage area), photosynthetic performance and elemental composition. Although some significant differences (p ≤ 0.05) were observed between treatments, essentially associated with the elemental composition of plant tissues, the most relevant variations were associated with seasonality. Overall, plants were found to not be affected by sediment contamination, under the tested concentrations, suggesting that recolonization with Z. noltei can be an effective restoration strategy for historically contaminated coastal areas.


Assuntos
Mercúrio , Poluentes Químicos da Água , Zosteraceae , Bioacumulação , Mercúrio/análise , Biomassa , Plantas , Sedimentos Geológicos , Poluentes Químicos da Água/análise
5.
Graefes Arch Clin Exp Ophthalmol ; 259(3): 759-768, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32945936

RESUMO

PURPOSE: To assess visual acuity in 5-year-old children with LEA chart and to estimate the frequency of reduced visual acuity in this age. METHOD: Study aimed at children attending the last year of preschool education in Public Kindergartens and Private Social Solidarity Institutions (IPSS) under the influence Regional Health Administration of the Médio Tejo, in Portugal. The 15-line LEA charts at 3 m were used and the presentation visual acuity was measured monocularly starting with the right eye. The ETDRS-fast methodology was used. RESULTS: A total of 3072 children participated, being 51% male and 54% from rural area. A rate of 13.7% children with a reduced level of visual acuity was found, that is, visual acuity worse or equal to 0.2 logMAR in at least one eye, or an interocular difference greater than two lines. CONCLUSION: This research shows that reduced VA frequency rate in children between 5 and 6 years old is high. The literature presents amblyopia (refractive and/or strabismic) and uncorrected refractive errors without amblyopia as the main cause of reduced VA in childhood, and these anomalies negatively affect child development, especially at the educational level. Reduced VA interferes with performance on a number of key tasks in the learning process. Thus, it is important to preserve the running program to identify these deficits and lead to their correction before the beginning of the school stage.


Assuntos
Ambliopia , Erros de Refração , Acuidade Visual , Ambliopia/fisiopatologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Portugal , Testes Visuais
6.
Braz J Med Biol Res ; 53(11): e10223, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33053112

RESUMO

Understanding the social determinants of telomere length is critical to evaluate the risk of early biological aging. We investigated sex differences on the association between socioeconomic status (SES) and demographic markers and leukocyte telomere length (LTL) in Brazilian adults. This cross-sectional study was conducted in a subsample (women=228; men=200) nested within the Pro-Saúde study, a prospective cohort study of university civil servants in Rio de Janeiro, Brazil (2012-2013). Adjusted multivariate models were used to test the relationship between SES markers (marital status, educational attainment, father's educational attainment, race/skin color, household income, and childhood experience of food deprivation) and LTL. After adjusting for age and potential health-related confounders, lower educational attainment was associated with shorter LTL among men (ß=-0.05, 95% confidence interval (CI)=95%CI: -0.10, 0.00, P=0.03). In women, LTL was inversely associated with unmarried status (ß=-0.05, 95%CI: -0.09, 0.00, P=0.03), lower father's educational attainment (ß=-0.05, 95%CI: -0.13, 0.00, P=0.04), and childhood experience of food deprivation (ß=-0.07, 95%CI: -0.13, 0.00, P=0.04). Our findings suggested that the association between SES markers and LTL differs according to sex. SES markers able to induce lifelong stress, reflected in LTL, appeared to be more related to individual factors in men, whereas in women they were family-related.


Assuntos
Telômero , Adulto , Envelhecimento , Brasil , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
7.
Braz. j. med. biol. res ; 53(11): e10223, 2020. tab
Artigo em Inglês | LILACS, Coleciona SUS | ID: biblio-1132494

RESUMO

Understanding the social determinants of telomere length is critical to evaluate the risk of early biological aging. We investigated sex differences on the association between socioeconomic status (SES) and demographic markers and leukocyte telomere length (LTL) in Brazilian adults. This cross-sectional study was conducted in a subsample (women=228; men=200) nested within the Pro-Saúde study, a prospective cohort study of university civil servants in Rio de Janeiro, Brazil (2012-2013). Adjusted multivariate models were used to test the relationship between SES markers (marital status, educational attainment, father's educational attainment, race/skin color, household income, and childhood experience of food deprivation) and LTL. After adjusting for age and potential health-related confounders, lower educational attainment was associated with shorter LTL among men (β=-0.05, 95% confidence interval (CI)=95%CI: -0.10, 0.00, P=0.03). In women, LTL was inversely associated with unmarried status (β=-0.05, 95%CI: -0.09, 0.00, P=0.03), lower father's educational attainment (β=-0.05, 95%CI: -0.13, 0.00, P=0.04), and childhood experience of food deprivation (β=-0.07, 95%CI: -0.13, 0.00, P=0.04). Our findings suggested that the association between SES markers and LTL differs according to sex. SES markers able to induce lifelong stress, reflected in LTL, appeared to be more related to individual factors in men, whereas in women they were family-related.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Telômero , Brasil , Envelhecimento , Estudos Transversais , Estudos Prospectivos
8.
Community Dent Health ; 34(2): 107-111, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28573842

RESUMO

OBJECTIVE: To evaluate caries prevalence and dental treatment needs in Portuguese children and teenagers, as well as fluorosis prevalence in 12-year-old children, in order to address public oral health program strategies. PARTICIPANTS: A representative stratified random cluster sample of 3,710 participants of 6, 12, and 18 years old was selected. A questionnaire was applied to determine sociodemographic data and some oral health determinants. The clinical examination was based on the ICDAS criteria, then adapted to DMFS index, and Dean's index for fluorosis. RESULTS: Caries prevalence at 6, 12, and 18 years old was 45.2%, 47.0%, and 67.6%, respectively. D5MFT scores were 1.18 (SD 0.06) and 2.51 (SD 0.10), respectively. Treatment needs at 12 and 18 years old were associated with 0.37 (SD 0.03) and 0.75 (SD 0.06) values in the "decayed" (D5) variable. SiC index at 12 years old was 2.68 (SD 1.68). Sealants were identified in 55% of 12-year-old children and the mean of sealants per individual was 3.61; also, moderate (2.2%) and severe (0.2%) levels of fluorosis were detected. CONCLUSIONS: The oral health situation in Portugal is favorable for young people, resulting in low treatment needs. The National Oral Health Promotion Program should be extended to include 18-year-olds.


Assuntos
Cárie Dentária/epidemiologia , Fluorose Dentária/epidemiologia , Avaliação das Necessidades , Adolescente , Criança , Índice CPO , Cárie Dentária/terapia , Fluorose Dentária/terapia , Inquéritos Epidemiológicos , Humanos , Portugal/epidemiologia , Prevalência , Índice de Gravidade de Doença
9.
Braz J Med Biol Res ; 50(5): e6019, 2017 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-28423121

RESUMO

Monoclonal B-cell lymphocytosis (MBL) is an asymptomatic clinical entity characterized by the proliferation of monoclonal B cells not meeting the diagnosis criteria for chronic lymphocytic leukemia (CLL). MBL may precede the development of CLL, but the molecular mechanisms responsible for disease progression and evolution are not completely known. Telomeres are usually short in CLL and their attrition may contribute to disease evolution. Here, we determined the telomere lengths of CD5+CD19+ cells in MBL, CLL, and healthy volunteers. Twenty-one CLL patients, 11 subjects with high-count MBL, and 6 with low-count MBL were enrolled. Two hundred and sixty-one healthy volunteers aged 0 to 88 years were studied as controls. After diagnosis confirmation, a flow cytometry CD19+CD5+-based cell sorting was performed for the study groups. Telomere length was determined by qPCR. Telomere length was similar in the 3 study groups but shorter in these groups compared to normal age-matched subjects that had been enrolled in a previous study from our group. These findings suggest that telomere shortening is an early event in CLL leukemogenesis.


Assuntos
Linfócitos B/patologia , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Linfocitose/genética , Linfocitose/patologia , Encurtamento do Telômero/genética , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Progressão da Doença , Feminino , Citometria de Fluxo , Marcadores Genéticos , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Padrões de Referência , Estatísticas não Paramétricas , Telômero/patologia
11.
J Endocrinol Invest ; 38(11): 1243-6, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25952298

RESUMO

PURPOSE: Telomere dysfunction and telomerase activation underlie cancer transformation. This study aims to investigate the contribution of telomere biology to pituitary tumor behavior. SUBJECTS AND METHODS: Samples from 50 patients with pituitary tumors (11 ACTH-secreting, 18 GH-secreting, and 21 non-secreting tumors) and 7 subjects without pituitary lesions were collected. The expressions of telomerase essential components TERT and TERC and tumor telomere content were measured by quantitative PCR techniques. RESULTS: Telomerase (TERT) expression was detected in 36% of tumors. No correlation was observed between TERT and TERC expression level and tumor size in any tumor type. There was no association between gene expression and clinical findings. Telomere content (T/S ratio) was similar between pituitary adenomas (0.39 ± 0.16) and normal pituitaries (0.47 ± 0.12; p = 0.24) and also was between the different adenoma types: ACTH-secreting (0.43 ± 0.08), GH-secreting (0.31 ± 0.12), and non-secreting (0.42 ± 0.20; p = 0.10) tumors. CONCLUSIONS: The telomere content and expression of telomerase components are comparable between normal pituitary glands and tumor tissues, suggesting that telomere biology does not play an important role in pituitary tumor development.


Assuntos
Expressão Gênica/fisiologia , Neoplasias Hipofisárias/metabolismo , Telomerase/metabolismo , Telômero/metabolismo , Adulto , Humanos , Pessoa de Meia-Idade , Neoplasias Hipofisárias/enzimologia , RNA/metabolismo
12.
Mol Ecol ; 23(15): 3838-48, 2014 08.
Artigo em Inglês | MEDLINE | ID: mdl-24118448

RESUMO

Zooxanthellate cnidarians are trophically complex, relying on both autotrophy and heterotrophy. Although several aspects of heterotrophy have been studied in these organisms, information linking prey capture with digestion is still missing. We used prey-specific PCR-based tools to assess feeding and prey digestion of two zooxanthellate cnidarians - the tropical sea anemone Aiptasia sp. and the scleractinian coral Oculina arbuscula. Prey DNA disappeared rapidly for the initial 1-3 days, whereas complete digestion of prey DNA required up to 10 days in O. arbuscula and 5 or 6 days in Aiptasia sp. depending on prey species. These digestion times are considerably longer than previously reported from microscopy-based examination of zooxanthellate cnidarians and prey DNA breakdown in other marine invertebrates, but similar to prey DNA breakdown reported from terrestrial invertebrates such as heteroptera and spiders. Deprivation of external prey induced increased digestion rates during the first days after feeding in O. arbuscula, but after 6 days of digestion, there were no differences in the remaining prey levels in fed and unfed corals. This study indicates that prey digestion by symbiotic corals may be slower than previously reported and varies with the type of prey, the cnidarian species and its feeding history. These observations have important implications for bioenergetic and trophodynamic studies on zooxanthellate cnidarians.


Assuntos
Antozoários/fisiologia , Digestão , Cadeia Alimentar , Processos Heterotróficos , Anêmonas-do-Mar/fisiologia , Animais , DNA/análise , Dados de Sequência Molecular , Comportamento Predatório , Análise de Sequência de DNA , Fatores de Tempo
14.
Leukemia ; 26(4): 700-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22005790

RESUMO

In cell and animal models, telomere erosion promotes chromosomal instability via breakage-fusion-bridge cycles, contributing to the early stages of tumorigenesis. However, evidence involving short telomeres in cancer development in humans is scarce, epidemiological and indirect. Here we directly implicate telomere shortening as a critical molecular event for malignant evolution in aplastic anemia (AA). Patients' telomere lengths at diagnosis of AA, while comparable to age-matched controls, inversely correlated with the probability of developing a cytogenetically abnormal clone. A significantly increased number of telomere signal-free chromosomal ends and chromosomal numerical and structural abnormalities were observed in bone marrow cells of patients with shorter telomeres in comparison with patients with longer telomeres and healthy subjects. The proportion of monosomy-7 cells in the bone marrow at diagnosis of AA inversely correlated with telomere length, years before the emergence of an autonomous and clinically detectable abnormal clone. Marrow cells of clinically healthy individuals carrying loss-of-function telomerase mutations and with extremely short telomeres also showed chromosomal instability in vitro. These results provide the first clinical direct evidence in humans that short telomeres in hematopoietic cells are dysfunctional, mediate chromosomal instability and predispose to malignant transformation in a human disease.


Assuntos
Idoso , Anemia Aplástica/genética , Transformação Celular Neoplásica/genética , Instabilidade Cromossômica , Sistema Hematopoético/metabolismo , Encurtamento do Telômero , Adolescente , Adulto , Idoso de 80 Anos ou mais , Anemia Aplástica/complicações , Aneuploidia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Bone Marrow Transplant ; 45(1): 25-30, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19525987

RESUMO

To determine the effects of TBI dose, fractionation and lung shielding on hematopoietic stem cell homing to the BM, BM cells were extracted from tibiae and femurs of B6-green fluorescent protein (GFP) mice and transplanted into B6 mice. Recipient mice had either: (i) no radiation, (ii) single-dose TBI at 13.6 Gy, (iii) single-dose TBI at 13.6 Gy with reduced lung exposure to 0.4 Gy by shielding, (iv) split-dose TBI at 12 Gy to twice per day over 4 days or (v) split-dose TBI at 12 Gy to twice per day over 4 days with reduced lung exposure to 0.36 Gy by shielding. The last radiation exposure preceded tail vein injection by 4-6 h. Mice were killed after 18 h. The homing of GFP-positive, lineage-negative cells was not significantly improved in any irradiated group compared with control. The homing of GFP-positive, lineage-negative, Kit-positive cells was significantly worse in all irradiated groups. TBI does not improve the homing of lineage-negative donor BM cells to the recipient marrow. The homing of lineage-negative, Kit-positive donor BM cells was significantly worse following TBI, with or without lung dose reduction.


Assuntos
Medula Óssea/fisiologia , Movimento Celular/fisiologia , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/fisiologia , Pulmão/efeitos da radiação , Irradiação Corporal Total , Animais , Movimento Celular/efeitos da radiação , Relação Dose-Resposta à Radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL
16.
Eur J Clin Invest ; 39(11): 1025-32, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19674077

RESUMO

BACKGROUND: Loss-of-function mutations in telomerase complex genes reduce telomerase activity and shorten overall telomere length in leucocytes, and they can clinically manifest as bone marrow failure (aplastic anaemia and dyskeratosis congenita) and familial pulmonary fibrosis. Telomeres are constituted of double-stranded tandem TTAGGG repeats followed by a 3' G-rich single-stranded overhang, a crucial telomeric structural component responsible for the t-loop formation. MATERIALS AND METHODS: We investigated the length of telomeric overhangs in 25 healthy individuals from 0 to 76 years of age, 16 patients with aplastic anaemia, and 13 immediate relatives using a non-denaturing in-gel method and the telomere-oligonucleotide ligation assay. RESULTS: Telomeric overhang lengths were constant from birth to eighth decade of life in healthy subjects, in contrast to overall telomere length, which shortened with ageing. Most patients with marrow failure and a telomerase gene mutation showed marked erosion of telomeric overhang associated with critically short telomeres; in other aplastic patients with normal genotypes, normal overall telomere lengths and who responded to immunosuppressive therapy, telomeric overhangs were maintained. CONCLUSIONS: Telomeric overhang erosion does not participate in physiological ageing but support a role for eroded telomeric overhangs and abnormal telomere structure in pathological shortening of telomeres, especially caused by loss-of-function telomerase mutations. Disrupted telomere structure caused by short telomeric overhangs may contribute to the mechanisms of abnormal haematopoietic compartment senescence and chromosomal instability in human bone marrow failure.


Assuntos
Anemia Aplástica/genética , Senescência Celular/genética , Mutação/genética , Telomerase/genética , Proteínas de Ligação a Telômeros/genética , Adolescente , Adulto , Idoso , Anemia Aplástica/metabolismo , Divisão Celular , Células Cultivadas , Criança , Pré-Escolar , Feminino , Variação Genética , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Telomerase/metabolismo , Proteínas de Ligação a Telômeros/metabolismo , Adulto Jovem
18.
Artigo em Inglês | MEDLINE | ID: mdl-15649771

RESUMO

We studied the amino acid and lipid dynamics during embryogenesis of Homarus gammarus. Major essential amino acids (EAA) in the last stage of embryonic development were arginine, lysine and leucine; major nonessential amino acids (NEAA) were glutamic acid, aspartic acid, valine and glycine. The highest percent of utilization occurred in respect to EAA (27.8%), mainly due to a significant decrease (p<0.05) of methionine (38.3%) and threonine (36.0%). NEAA also decreased significantly (p<0.05, 11.4%), namely serine (38.1%), tyrosine (26.4%) and glutamic acid (25.7%). In contrast, the free amino acid content increased significantly (p<0.05) during embryonic development, especially the free nonessential amino acids (FNEAA). In the last stage, the most abundant FNEAA were glycine, proline, alanine and taurine, and the major free essential amino acids (FEAA) were arginine, lysine and leucine. Lipid content decreased significantly (p<0.05) during embryonic development. A substantial decrease in all neutral lipid classes was observed (>80% of utilization). Major fatty acids were 16:0, 18:0, 18:1n-9, 18:2n-6, 18:3n-3, 20:5n-3 and 22:6n-3. Unsaturated (UFA) and saturated fatty acids (SFA) were used up at similar rates (76.5% and 76.3%, respectively). Within UFA, monounsaturates (MUFA) were consumed more than polyunsaturates (PUFA) (82.9% and 67.5%, respectively).


Assuntos
Aminoácidos/metabolismo , Desenvolvimento Embrionário , Metabolismo dos Lipídeos , Nephropidae/embriologia , Nephropidae/metabolismo , Aminoácidos/análise , Animais , Ácidos Graxos/análise , Ácidos Graxos/química , Feminino , Lipídeos/análise , Lipídeos/classificação , Óvulo/química , Óvulo/crescimento & desenvolvimento , Água/análise
19.
Braz J Med Biol Res ; 36(12): 1653-7, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14666249

RESUMO

The multidrug resistance P-glycoprotein is a transmembrane efflux pump expressed by lymphocytes and is involved in their cytolytic activity. In the present study, we investigated the age-related changes of P-glycoprotein function in normal peripheral blood lymphocytes. Blood samples from 90 normal volunteers (age range, 0 to 86 years) were analyzed. P-glycoprotein function was assessed by the flow cytometric rhodamine 123 assay. P-glycoprotein function was highest in cord blood and progressively declined with age in peripheral blood T CD4+ and CD8+ cells. In contrast, P-glycoprotein function did not vary with age in CD19+ B or CD16+CD56+ natural killer cells. These data suggest that the decline in P-glycoprotein function in T CD4+ and CD8+ lymphocytes as a function of age may contribute to the decrease in T cell cytolytic activity with aging.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Resistência a Múltiplos Medicamentos/fisiologia , Linfócitos T/fisiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Criança , Pré-Escolar , Citometria de Fluxo , Corantes Fluorescentes , Humanos , Lactente , Recém-Nascido , Células Matadoras Naturais/fisiologia , Pessoa de Meia-Idade , Rodamina 123 , Células-Tronco/fisiologia
20.
Braz. j. med. biol. res ; 36(12): 1653-1657, Dec. 2003. ilus
Artigo em Inglês | LILACS | ID: lil-350469

RESUMO

The multidrug resistance P-glycoprotein is a transmembrane efflux pump expressed by lymphocytes and is involved in their cytolytic activity. In the present study, we investigated the age-related changes of P-glycoprotein function in normal peripheral blood lymphocytes. Blood samples from 90 normal volunteers (age range, 0 to 86 years) were analyzed. P-glycoprotein function was assessed by the flow cytometric rhodamine 123 assay. P-glycoprotein function was highest in cord blood and progressively declined with age in peripheral blood T CD4+ and CD8+ cells. In contrast, P-glycoprotein function did not vary with age in CD19+ B or CD16+CD56+ natural killer cells. These data suggest that the decline in P-glycoprotein function in T CD4+ and CD8+ lymphocytes as a function of age may contribute to the decrease in T cell cytolytic activity with aging.


Assuntos
Adolescente , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adulto , Pessoa de Meia-Idade , Humanos , Resistência a Múltiplos Medicamentos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Linfócitos T , Fatores Etários , Idoso de 80 Anos ou mais , Citometria de Fluxo , Corantes Fluorescentes , Rodamina 123
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