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1.
Environ Monit Assess ; 189(10): 499, 2017 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-28895007

RESUMO

Concentrations of essential (Cu, Mn, and Zn) and toxic (Cr, Cd, and Pb) trace metals in 30 raw cow's milk samples were quantified using flame atomic absorption spectrometry. The samples were collected from the Nara-Awudarda, Tana-Abo, and Kosoye Amba-Rass sites in North Gondar, Ethiopia, preserved in a deep freezer (-20 °C), and then digested by Kjeldahl apparatus with HNO3/H2O2 (5:2; v/v) at 300 °C for 2.5 h. The data were subject to principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA). Overall hazard quotient (HQ) and carcinogenic risk (CR) values were also estimated to assess metal-related health risks. The mean concentrations of Cr, Mn, Cu, Zn, Cd, and Pb in the milk samples ranged 0.468-0.828, 1.614-2.806, 0.840-1.532, 1.208-5.267, ND-0.330, and ND-0.186 mg/kg, respectively. The lowest values were obtained for Kosoye Amba-Rass milk samples, while the highest were found for those collected from Nara-Awudarda milk samples, probably due to high mineral enrichment and metal leaching (especially Cd and Pb) from coal deposits. PCA revealed clustering of samples with respect to their geographic origin. Validation of PLS-DA model showed 100% classification efficiency using external validation samples and detected Cd and Cu as trace metal markers. The HQ and CR values were within the safe level; however, the former is close to the alert threshold level for Nara-Awudarda milk samples. Thus, further studies on common foodstuffs, constituting a higher proportion in the local diet, are required in this area to provide a complete risk assessment.


Assuntos
Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Metais Pesados/análise , Leite/química , Oligoelementos/análise , Animais , Bovinos , Etiópia , Fazendas , Feminino , Leite/normas , Medição de Risco , Espectrofotometria Atômica
2.
Diabet Med ; 28(8): 886-95, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21749441

RESUMO

AIMS: To perform a systematic review of observational studies which analyse tendon alterations in patients with diabetes mellitus compared with healthy individuals. METHODS: Data collection was performed, with no language restriction, using the databases of PubMed/Medline, BIREME, CINAHL, LILACS and Cochrane, as well as the references found in these studies. Three reviewers performed independent extractions of articles. Subsequently, these reviewers analysed the articles, focusing on their methodological quality, using the appropriate scale to evaluate observational studies from the Agency for Healthcare Research and Quality. RESULTS: Six articles were included in the analysis. Of these, four had used ultrasonographic diagnostics, one computed tomography and one magnetic resonance imaging. The patient pool comprised 396 individuals. All the articles evaluated tendon thickness and presented heterogeneous results. Two articles stated thickening or increased volume of the tendons in diabetic people, one article did not report any alteration, the fourth failed to determine any alterations and the fifth showed thinning of the tendons. The arrangement of collagen fibrils and the presence of calcification were analysed in only one article (n = 80), showing that 88.10% (n = 68) of individuals with diabetes presented disorientation of collagen fibril arrangement, while only 10% (n = 1) of healthy individuals presented this condition. Regarding tendon calcification, the article showed diabetic individuals with higher values than healthy individuals. CONCLUSIONS: All the articles indicated some relation between diabetes mellitus and tendon alterations in human beings, but due to methodological drawbacks, this association could not be sustained.


Assuntos
Tendão do Calcâneo/patologia , Glicemia/metabolismo , Calcinose/patologia , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 2/patologia , Tendões/patologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Masculino
3.
J Fish Biol ; 75(9): 2209-25, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20738683

RESUMO

Ancistrus is the most speciose genus of the tribe Ancistrini, with 58 valid species and many yet to be described. Cytogenetic studies were conducted on five apparently undescribed species from the Amazon basin, which showed different diploid numbers: Ancistrus sp. Purus (2n = 34); Ancistrus sp. Macoari (2n = 46); Ancistrus sp. Dimona (2n = 52); Ancistrus sp. Vermelho (2n = 42) and Ancistrus sp. Trombetas (2n = 38). All species possessed only one pair of NOR-carrying chromosomes, but with extensive variation in both the location on the chromosome as well as in the position of the ribosomal sites on the karyotype. The karyotypic evolution of Ancistrus species seems to be based on chromosomal rearrangements, with a tendency to a reduction of the diploid number. Two new instances of XX/XY sex chromosomes for Ancistrus species, based on the heteromorphism in the male karyotype, were also recorded. The large karyotypic diversity among Ancistrus species may be related to biological and behavioural characteristics of these fish that include microhabitat preferences, territoriality and specialized reproductive tactics. These characteristics may lead to a fast rate of fixation of chromosomal mutations and eventually speciation across the basin.


Assuntos
Peixes-Gato/classificação , Evolução Molecular , Cariotipagem , Animais , Peixes-Gato/anatomia & histologia , Peixes-Gato/genética , Diploide , Feminino , Masculino , Cromossomos Sexuais/genética
4.
Braz J Biol ; 68(1): 45-50, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18470377

RESUMO

Several groups of Amazonian fishes exhibit behavioral, morphological and physiological characteristics that allow occupying hypoxic environments, despite the energetic costs of living in such harsh conditions. One of the supposed advantages of occupying hypoxic habitats would be a lower predation pressure resulting from a lower number of piscivorous fishes in those environments. We tested this hypothesis in an area of the Amazon River floodplain through gill net fishing in normoxic and hypoxic habitats. From the 103 species caught, 38 were classified as piscivores. We found no difference in the number of piscivorous species captured in hypoxic and normoxic habitats (chi2 = 0.23; p = 0.63; df = 1) but piscivorous individuals were more numerous in normoxic than in hypoxic sampling stations (chi2 = 104.4; p < 0.001; df = 1). This indicates that environments submitted to low oxygen conditions may in fact function as refuges against piscivorous fishes in the Amazonian floodplains.


Assuntos
Comportamento Animal/fisiologia , Peixes/fisiologia , Oxigênio , Animais , Brasil , Peixes/classificação , Rios
5.
Braz. j. biol ; 68(1): 45-50, Feb. 2008. mapas, graf, tab
Artigo em Inglês | LILACS | ID: lil-482182

RESUMO

Several groups of Amazonian fishes exhibit behavioral, morphological and physiological characteristics that allow occupying hypoxic environments, despite the energetic costs of living in such harsh conditions. One of the supposed advantages of occupying hypoxic habitats would be a lower predation pressure resulting from a lower number of piscivorous fishes in those environments. We tested this hypothesis in an area of the Amazon River floodplain through gill net fishing in normoxic and hypoxic habitats. From the 103 species caught, 38 were classified as piscivores. We found no difference in the number of piscivorous species captured in hypoxic and normoxic habitats (chi2 = 0.23; p = 0.63; df = 1) but piscivorous individuals were more numerous in normoxic than in hypoxic sampling stations (chi2 = 104.4; p < 0.001; df = 1). This indicates that environments submitted to low oxygen conditions may in fact function as refuges against piscivorous fishes in the Amazonian floodplains.


Diversos grupos de peixes amazônicos apresentam mecanismos para suportar condições de hipóxia, incluindo especializações comportamentais, morfológicas e fisiológicas, apesar do custo energético envolvido. Uma das supostas vantagens em ocupar ambientes hipóxicos seria a redução da pressão de predação, devido à presença de um menor número de peixes piscívoros. Testamos esta hipótese em um ambiente de várzea do rio Amazonas, por meio de coleta de peixes com malhadeiras em ambientes hipóxicos e normóxicos. Das 103 espécies capturadas, 38 foram classificadas como piscívoras. Não houve diferença no número de espécies piscívoras e não piscívoras nos dois tipos de ambientes amostrados (chi2 = 0,23; p = 0,63; gl = 1), mas a proporção de peixes piscívoros foi maior sob condições de normóxia (chi2 = 104,40; p < 0,001; gl = 1). Isto indica que ambientes com baixa concentração de oxigênio dissolvido podem de fato funcionar como locais de refúgio contra peixes piscívoros nas várzeas amazônicas.


Assuntos
Animais , Comportamento Animal/fisiologia , Peixes/fisiologia , Oxigênio , Brasil , Peixes/classificação , Rios
6.
Arq Bras Cardiol ; 72(5): 593-600, 1999 May.
Artigo em Inglês, Português | MEDLINE | ID: mdl-10668229

RESUMO

OBJECTIVE: To assess the results observed during the early postoperative period in patients who had the posterior coronary arteries revascularized without cardiopulmonary bypass (CPB), in regard to the following parameters: age, sex, bypass grafts types, morbidity and mortality. METHODS: From January 1995 to June 1998, 673 patients underwent myocardial revascularization (MR). Of this total, 607 (90.20%) MR procedures were performed without CPB. The posterior coronary arteries (PCA) were revascularized in 298 (44.27%) patients, 280 (93.95%) without CPB. The age of the patients ranged from 37 to 88 years (mean, 61 years). The male gender predominated, with 198 men (70.7%). The revascularization of the posterior coronary arteries had the following distribution: diagonalis artery (31 patients, 10%); marginal branches of the circumflex artery (243 patients, 78.7%); posterior ventricular artery (4 patients, 1.3%); and posterior descending artery (31 patients, 10%). RESULTS: Procedure-related complications without death occurred in 7 cases, giving a morbidity of 2.5%. There were 11 deaths in the early postoperative period (mortality of 3.9%). CONCLUSION: Similarly to the anterior coronary arteries, the posterior coronary arteries may benefit from myocardial revascularization without CPB.


Assuntos
Vasos Coronários/cirurgia , Revascularização Miocárdica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Circulação Extracorpórea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Revascularização Miocárdica/mortalidade
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