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2.
Nat Plants ; 5(12): 1222-1228, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31792395

RESUMO

Mast seeding is one of the most intriguing reproductive traits in nature. Despite its potential drawbacks in terms of fitness, the widespread existence of this phenomenon suggests that it should have evolutionary advantages under certain circumstances. Using a global dataset of seed production time series for 219 plant species from all of the continents, we tested whether masting behaviour appears predominantly in species with low foliar nitrogen and phosphorus concentrations when controlling for local climate and productivity. Here, we show that masting intensity is higher in species with low foliar N and P concentrations, and especially in those with imbalanced N/P ratios, and that the evolutionary history of masting behaviour has been linked to that of nutrient economy. Our results support the hypothesis that masting is stronger in species growing under limiting conditions and suggest that this reproductive behaviour might have evolved as an adaptation to nutrient limitations and imbalances.


Assuntos
Nitrogênio/metabolismo , Fósforo/metabolismo , Sementes/metabolismo , Evolução Biológica , Clima , Nutrientes/metabolismo , Estações do Ano , Sementes/crescimento & desenvolvimento
3.
Forensic Sci Int ; 265: 29-33, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26826850

RESUMO

Cholesterol levels in the median nerve were studied at various post-mortem intervals (PMIs). Single median nerve samples were collected from the wrists of 36 subjects during forensic autopsies of subjects with known circumstances and times of death. Although the absolute values varied, increments in cholesterol concentration were recorded. Subsequently, 16 subjects who did not suffer of any neurological and/or metabolic diseases with known times and circumstances of death were enrolled. For each enrolled subject, two samples were collected from the wrist at an interval of approximately two hours (t1 and t2). The obtained results revealed a gradual increase in cholesterol level with increasing time since death. The cholesterol concentration data obtained for each subject at t1 and t2 were correlated with the time since death, a linear interpolation was applied, and the PMI was back-calculated. Similar trends were obtained for the samples collected at similar PMIs; thus, three groups were considered: PMI<48h, 4878h. Good correlation coefficients were obtained, especially for the first group (R(2)=0.9362) for which the PMI could be calculated with an error that ranged from -4 to 5.9h. Although it requires further confirmation via analyses of larger numbers of samples, the method proposed here can currently be applied to PMI determinations.


Assuntos
Colesterol/análise , Nervo Mediano/química , Mudanças Depois da Morte , Adulto , Idoso , Feminino , Patologia Legal , Humanos , Masculino , Nervo Mediano/patologia , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores de Tempo , Adulto Jovem
4.
J R Army Med Corps ; 158(4): 338-40, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23402075

RESUMO

Balkans Syndrome is a recent term that has been widely used in the media to describe a heterogenous group of medical conditions that presented in soldiers following deployment on military operations to the former Yugoslavia and its neighbouring countries. These individuals had been subjected to an intense and protracted course of vaccinations (termed hypervaccination) prior to deployment, which has subsequently been implicated by the media as the cause of this disease. We describe the case of a 33-year old army officer, who received twenty vaccinations and boosters during the period 2000-2006, and was subsequently diagnosed with multiple sclerosis in 2008.


Assuntos
Militares , Esclerose Múltipla/etiologia , Vacinação/efeitos adversos , Vacinas/efeitos adversos , Adulto , Diagnóstico Diferencial , Relação Dose-Resposta a Droga , Humanos , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla/diagnóstico , Síndrome , Vacinas/administração & dosagem , Iugoslávia
5.
Forensic Sci Int ; 115(1-2): 9-14, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11056266

RESUMO

In order to connect the appearance of macrophages and giant cells in pulmonary tissue with the time of asphyxia the authors analyzed 50 asphyxiated human lungs paying their attention on the number of alveolar and interstitial macrophages and giant cells. They compared histological specimens of 25 asphixiated humans lungs following a slow asphyxia (30 min or more) with 25 histological specimens of asphyxiated human lungs following a rapid asphyxia (10-15 min). Alveolar and interstitial macrophages and giant cells per section, were considered and numbered. Controls were done on histological examination of traumatized lungs. In the pulmonary alveoli following on acute asphyxia there were 27.7+/-4.4 macrophages per section. Subjects dead after a slow asphyxiation showed 68.2+/-7.1 alveolar macrophages per section (p<0.001). Interstitial macrophages were also frequently present. No differences are detectable in the number of polynuclear giant cells between rapidly and slowly asphyxiated human lungs. The number of alveolar and interstitial macrophages per section can be considered as a further histological evidence of a slow asphyxia and can differentiate a slow asphyxia from an acute one.


Assuntos
Asfixia/patologia , Pulmão/patologia , Macrófagos Alveolares/patologia , Mudanças Depois da Morte , Autopsia , Estudos de Casos e Controles , Contagem de Células , Células Gigantes/patologia , Humanos , Imuno-Histoquímica , Ativação Linfocitária , Ativação de Macrófagos , Fatores de Tempo
6.
J Clin Forensic Med ; 8(2): 86-92, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15274977

RESUMO

We report a case of CO intoxication caused by a motor vehicle's faulty heating-system. A truck driver experienced severe mental deterioration, behavioural changes and delirium after acute CO intoxication and committed suicide 15 months later. This report examines the pathogenetic mechanism of CO, the immediate and delayed consequences of CO intoxication, diagnostic difficulties and current treatment options. The medical-legal aspects of the case are discussed.

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