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1.
Am J Bot ; 109(3): 366-376, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34973037

RESUMO

PREMISE: Maternal effects have been demonstrated to affect offspring performance in many organisms, and in plants, seeds are important mediators of these effects. Some woody plant species maintain long-lasting canopy seed banks as an adaptation to wildfires. Importantly, these seeds stored in serotinous cones are produced by the mother plant under varying ontogenetic and physiological conditions. METHODS: We sampled the canopy seed bank of a highly serotinous population of Pinus pinaster to test whether maternal age and growth and the environmental conditions during each crop year affected seed mass and ultimately germination and early survival. After determining retrospectively the year of each seed cohort, we followed germination and early survival in a semi-natural common garden. RESULTS: Seed mass was related to maternal age and growth at the time of seed production; i.e., slow-growing, older mothers had smaller seeds, and fast-growing, young mothers had larger seeds, which could be interpreted either as a proxy of senescence or as a maternal strategy. Seed mass had a positive effect on germination success, but aside from differences in seed mass, maternal age had a negative effect and diameter had a positive effect on germination timing and subsequent survival. CONCLUSIONS: The results highlight the importance of maternal conditions combined with seed mass in shaping seedling establishment. Our findings open new insights in the offspring performance deriving from long-term canopy seed banks, which may have high relevance for plant adaptation.


Assuntos
Banco de Sementes , Traqueófitas , Germinação/fisiologia , Humanos , Idade Materna , Estudos Retrospectivos , Sementes/fisiologia
3.
Allergol Immunopathol (Madr) ; 47(2): 128-132, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30249451

RESUMO

INTRODUCTION: Beta-lactams are the most frequently used antibiotics in pediatric age. Anaphylactic reactions may occur and need to be properly studied, but studies in children are scarce. OBJECTIVE: Characterization of case reports of anaphylaxis in children referred to an allergy department with suspected beta-lactams hypersensitivity. MATERIALS AND METHODS: Retrospective analysis of all children referred to our Drug Allergy Center with suspected beta-lactams hypersensitivity between January 2011 and December 2016. Description of the drug allergy work-up performed studied according to standardized diagnostic procedures of ENDA/EAACI, including specific-IgE assay, skin prick and intradermal tests and diagnostic/alternative drug challenge tests. RESULTS: 146 children with suspected beta-lactams hypersensitivity were studied, and in 21 (14.4%) the diagnosis was confirmed. In all of them, except for three children, an alternative beta-lactam was found. In seven children (33.3% of those with confirmed beta-lactams hypersensitivity) anaphylaxis was confirmed, and all of them described reactions with cutaneous and respiratory or gastrointestinal involvement. The culprit drug was amoxicillin in six and flucloxacillin in one. In this sample, we also performed oral challenge with cefuroxime, being negative in all cases. Almost all cases of confirmed anaphylaxis (six from seven cases) were IgE mediated, with positive skin tests despite negative serum specific-IgE. CONCLUSIONS: Allergic reactions to beta-lactams, although rare in children, require a detailed clinical history and a specialized drug allergy work-up to allow a correct diagnosis as well as to avoid the possibility of a potential life-threatening reaction and provide alternative drugs.


Assuntos
Alérgenos/imunologia , Anafilaxia/diagnóstico , Hipersensibilidade a Drogas/diagnóstico , Pele/patologia , beta-Lactamas/imunologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina E/sangue , Lactente , Masculino , Estudos Retrospectivos , Testes Cutâneos , Inquéritos e Questionários
5.
Eur Ann Allergy Clin Immunol ; 50(5): 211-216, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30028111

RESUMO

Summary: Background and Objective. Drug-induced anaphylaxis (DIA) is the most common cause of fatal anaphylaxis. We aimed to characterize patients with DIA and their allergological workup. Methods. Systematic review of patients with history of DIA referred to our center over 7 years. Results. Included 125 patients (10% pediatric age), being 36 years the median age of first episode (from 1 to 74 years). The main culprits were nonsteroidal anti-inflammatory drugs (NSAIDs) (43%), antibiotics (42%) and anesthetic agents (6%). In 24% the reactions occurred in hospital setting and 14% perioperative. The etiology was confirmed in 75% through allergological workup. Conclusions. NSAIDs and antibiotics were responsible for most of DIA. The heterogeneity of mechanisms, the severity of the reactions and the lack of standardized in vivo and/or in vitro tests for some drugs do not allow to confirm the diagnosis in all cases. Patients with DIA should be evaluated in specialized centers to perform accurate diagnosis, to prevent recurrence and to find safe alternatives.


Assuntos
Alérgenos/imunologia , Anafilaxia/epidemiologia , Anestésicos/imunologia , Antibacterianos/imunologia , Anti-Inflamatórios não Esteroides/imunologia , Hipersensibilidade a Drogas/epidemiologia , Adolescente , Adulto , Idoso , Anafilaxia/diagnóstico , Criança , Pré-Escolar , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/imunologia , Feminino , Humanos , Testes Imunológicos/normas , Lactente , Masculino , Pessoa de Meia-Idade , Portugal/epidemiologia , Adulto Jovem
6.
Occup Med (Lond) ; 68(6): 364-369, 2018 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-29939307

RESUMO

BACKGROUND: The promotion and maintenance of workers' mental health is an increasingly important issue, both for employers and society. Previous research has shown that job characteristics (i.e. demands, control and support) are significantly associated with employees' mental well-being. However, changes in work characteristics have given rise to the emergence of new job demands, leading to work-family life conflict. AIMS: To investigate the association between work-family life conflict and employee mental well-being. METHODS: A cross-sectional study with two samples: one sample comprising clothes store sales employees and the other comprising call centre operators. Logistic regression models were used to examine the effects of work-family life conflict on employee well-being. RESULTS: After controlling for job demands, job control, supervisory support and co-workers support, work-family life conflict was associated with employee mental well-being. CONCLUSIONS: Work-family life conflict is an important factor to explain employee well-being and productivity and should be addressed as well as work factors.


Assuntos
Transtornos Mentais/etiologia , Equilíbrio Trabalho-Vida/métodos , Carga de Trabalho/psicologia , Adulto , Estudos Transversais , Feminino , Humanos , Satisfação no Emprego , Modelos Logísticos , Masculino , Transtornos Mentais/epidemiologia , Transtornos Mentais/psicologia , Pessoa de Meia-Idade , Inquéritos e Questionários , Equilíbrio Trabalho-Vida/tendências , Carga de Trabalho/normas
7.
Eur Ann Allergy Clin Immunol ; 48(6): 212-219, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27852424

RESUMO

BACKGROUND: Beta-lactams antibiotics (BL) are the most frequent elicitors of allergic drug reactions. The aim of our study was to characterize the patients referred with suspected hypersensitivity (HS) to BL. METHODS: Over a three-year period (2011-2013), a total of 234 adult and paediatric patients (pts) with suspected HS to BL were investigated according to the European Network for Drug Allergy guidelines. RESULTS: HS to BL was confirmed in 43 pts (18%), without differences between adult and paediatric pts; anaphylaxis was reported by 20 pts. Diagnosis was ascertained by: serum-specific IgE antibodies in 5 pts (12%), skin prick tests in 5 (12%), intradermal tests in 25 (58%), 3 with delayed reading, and the remaining 8 (18%) by drug provocation tests. Penicillins / derivatives were the culprit drugs in 39 pts, mainly amoxicillin, and cephalosporins in 4. CONCLUSION: In most of these patients with suspected HS to BL, allergological work-up was negative and HS was excluded. One fourth of confirmed cases had a plausible non-IgE mediated mechanism.


Assuntos
Antibacterianos/efeitos adversos , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/epidemiologia , beta-Lactamas/efeitos adversos , Adolescente , Adulto , Idoso , Antibacterianos/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Testes Imunológicos , Lactente , Masculino , Pessoa de Meia-Idade , Adulto Jovem , beta-Lactamas/imunologia
8.
Am J Bot ; 103(9): 1582-91, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27620182

RESUMO

PREMISE OF THE STUDY: Serotiny, the maintenance of ripe seeds in closed fruits or cones until fire causes dehiscence, is a key adaptive trait of plants in fire-prone ecosystems, but knowledge of phenotypic plasticity for cone retention in woody plants is extremely scarce. On the basis of published literature and our field observations, we hypothesized that increased aridity might decrease the aerial seed bank as a plastic response, not necessarily adaptive. METHODS: We used a Pinus halepensis common garden replicated in three contrasted sites (mild, cold, and dry) to separate population differentiation from phenotypic plasticity of cone serotiny and canopy cone bank (CCB). Differences in growth among trees of the same provenance allowed us to include size effect as a proxy of ontogenetic age for the same chronological age of the trees. KEY RESULTS: Tree size had a strong negative effect on serotiny, but serotiny degree differed among trial sites even after accounting for size effects. As hypothesized, serotiny was lower at the harsh (dry and cold) sites compared with the mild site. Genetic variation for size-dependent cone serotiny and significant population × site interaction were confirmed, the latter implying different plasticity of serotiny among populations. Population differentiation for CCB showed an ecotypic trend, with positive correlation with temperature oscillation (continentality) and negative correlation with summer rainfall. CONCLUSIONS: Growth-limiting environments exacerbated the precocious release of seeds, contrary to the ecotypic trend found for the aerial cone bank, suggesting a counter-gradient plasticity. This plastic response is potentially maladaptive under a scenario of frequent wildfires.


Assuntos
Incêndios , Interação Gene-Ambiente , Pinus/fisiologia , Dispersão de Sementes , Meio Ambiente , Fenótipo , Pinus/genética , Reprodução
9.
Stress Health ; 31(2): 106-14, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24124018

RESUMO

The paradigm of this study is positive occupational psychology, with the job demands-resources model as the research model and the Conservation of Resources theory as the general stress theory. The research design analyses the job demands-resources model's dynamic nature with normal and reversed causation effects between work characteristics and psychological well-being among Portuguese firefighters. In addition, we analyse a positive (engagement) dimension and a negative (burnout) dimension in the firefighters' well-being, because previously, studies have merely focused on the strain or stress of these professionals. The research questionnaire was distributed to a sample of 651 firefighters, and a two-wave full panel design was used. Cross-lagged panel analyses indicated that the causal direction of the relationship between organizational demands and burnout is reciprocal. Also, we found that the reciprocal model, including cross-lagged reciprocal relationships between organizational demands/supervisory support and burnout/engagement, respectively, is what fits the data best. Practical implications to develop organizational change programmes and suggestions for future research regarding the promotion of occupational health are discussed.


Assuntos
Esgotamento Profissional/psicologia , Bombeiros/psicologia , Motivação , Transtornos de Estresse Traumático/psicologia , Trabalho , Adulto , Feminino , Humanos , Satisfação no Emprego , Estudos Longitudinais , Masculino , Modelos Psicológicos , Saúde Ocupacional , Portugal , Apoio Social , Inquéritos e Questionários , Carga de Trabalho
10.
Eur Ann Allergy Clin Immunol ; 46(4): 154-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25053634

RESUMO

Although the standard of care for cow's milk (CM) allergy is strict food avoidance, oral immunotherapy (OIT) is being widely investigated as an alternative management option in certain cases. Immediate adverse reactions to OIT have been described, but its long-term effects are much less often reported. We present the case of a girl diagnosed with IgE-mediated CM allergy that was proposed for our CM OIT protocol at the age of 3 years. The first sessions (dose escalation up to 5 ml) were well tolerated, however eight hours after her daily morning dose of 5 ml CM the child developed late episodes of vomiting. No other symptoms, particularly immediately after CM ingestion, were reported. These episodes became progressively worse and on the third day she presented mild dehydration and blood eosinophilia. After OIT interruption, a progressive clinical improvement was observed. An esophageal endoscopy was performed, showing signs of eosinophilic esophagitis (EoE) with peak 20 eosinophils/hpf. After treatment with topical swallowed fluticasone (500 mcg bid) and a CM-free diet for 4 months, the child was asymptomatic and endoscopy and biopsy findings were normal.The long-term effects of milk OIT are still in part unknown. We hypothesize that eosinophilic esophagitis may have been a consequence of OIT in this case. The findings seem to indicate that food allergy may play a role in the pathogenesis of esophageal eosinophilia and stress the importance of a well programmed long-term follow-up of patients that have undergone milk OIT.


Assuntos
Dessensibilização Imunológica/efeitos adversos , Dessensibilização Imunológica/métodos , Esofagite Eosinofílica/etiologia , Hipersensibilidade a Leite/terapia , Leite/efeitos adversos , Administração Oral , Animais , Pré-Escolar , Feminino , Humanos
11.
J Evol Biol ; 26(9): 1912-24, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23944274

RESUMO

A plastic response towards enhanced reproduction is expected in stressful environments, but it is assumed to trade off against vegetative growth and efficiency in the use of available resources deployed in reproduction [reproductive efficiency (RE)]. Evidence supporting this expectation is scarce for plants, particularly for long-lived species. Forest trees such as Mediterranean pines provide ideal models to study the adaptive value of allocation to reproduction vs. vegetative growth given their among-population differentiation for adaptive traits and their remarkable capacity to cope with dry and low-fertility environments. We studied 52 range-wide Pinus halepensis populations planted into two environmentally contrasting sites during their initial reproductive stage. We investigated the effect of site, population and their interaction on vegetative growth, threshold size for female reproduction, reproductive-vegetative size relationships and RE. We quantified correlations among traits and environmental variables to identify allocation trade-offs and ecotypic trends. Genetic variation for plasticity was high for vegetative growth, whereas it was nonsignificant for reproduction. Size-corrected reproduction was enhanced in the more stressful site supporting the expectation for adverse conditions to elicit plastic responses in reproductive allometry. However, RE was unrelated with early reproductive investment. Our results followed theoretical predictions and support that phenotypic plasticity for reproduction is adaptive under stressful environments. Considering expectations of increased drought in the Mediterranean, we hypothesize that phenotypic plasticity together with natural selection on reproductive traits will play a relevant role in the future adaptation of forest tree species.


Assuntos
Adaptação Biológica/fisiologia , Meio Ambiente , Fenótipo , Pinus/crescimento & desenvolvimento , Estresse Fisiológico/fisiologia , Secas , Fertilidade/fisiologia , Região do Mediterrâneo , Pinus/genética , Reprodução/fisiologia
13.
Allergol Immunopathol (Madr) ; 38(6): 300-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20478649

RESUMO

BACKGROUND: Few studies have been performed in children with suspected betalactam allergy. We aimed to assess the role of the drug provocation test (DPT) with betalactams in a paediatric setting and to study the association between allergy to betalactam antibiotics and other allergic diseases. METHODS: We included all the patients under 15 years old who were consecutively referred to the Immunoallergy Department, Dona Estefânia Hospital, Portugal (January 2002 to April 2008) for a compatible history of allergic reaction to betalactam. All were submitted to a DPT. Children were proposed to perform skin tests (ST) to betalactam antibiotics followed by DPT. If they decline ST, a DPT with the culprit drug was performed. RESULTS: We studied 161 children, 60% were boys, with a median age of 5 years old at the time of the DPT. Thirty-three patients (20.5%) had an immediate reaction and 33 (20.5%) a non-immediate reaction. The severity of the reported reactions was low in most cases. Skin tests to betalactams were performed in 47 children and were positive in 8. DPT was positive in only one (3.4%) of the patients skin tested and in 11 (13.4%) of those not skin tested. The severity of the DPT reaction was low. Asthma and food allergy were associated with a positive DPT in the later group. CONCLUSIONS: DPT seems a safe procedure even in the absence of ST in non-severe cases. This could be a practical option in infants and pre-school children, where ST are painful and difficult to perform. Additional caution should be taken in children with asthma and food allergy.


Assuntos
Testes de Provocação Brônquica , Hipersensibilidade a Drogas/epidemiologia , Hipersensibilidade a Drogas/imunologia , Hipersensibilidade Alimentar/epidemiologia , Hipersensibilidade Alimentar/imunologia , beta-Lactamas/efeitos adversos , Adolescente , Alérgenos/administração & dosagem , Alérgenos/uso terapêutico , Criança , Pré-Escolar , Progressão da Doença , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/fisiopatologia , Estudos de Viabilidade , Feminino , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/fisiopatologia , Humanos , Imunização , Masculino , Portugal , beta-Lactamas/administração & dosagem
15.
Am J Bot ; 95(7): 833-42, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21632409

RESUMO

Age and size at the first reproduction and the reproductive allocation of plants are linked to different life history strategies. Aleppo pine only reproduces through seed, and, as such, early female reproduction confers high fitness in its infertile highly fire-prone habitats along the Mediterranean coast because life expectancy is short. We investigated the extent of ecotypic differentiation in female reproductive allocation and examined the relation between early female reproduction and vegetative growth. In a common-garden experiment, the threshold age and size at first female reproduction and female reproductive allocation at age seven differed significantly among Aleppo pine provenances of ecologically distinct origin. Significant correlations among reproductive features of the provenances and the ecological traits of origin were found using different analytical tools. In nonlinear models of cone counts vs. stem volume, medium-sized trees (not the largest trees) produced the highest cone yield, confirming that, at the individual level, early female reproduction is incompatible with fast vegetative growth. The contribution of founder effects and adaptation to contrasting fire regimes may be confounding factors. But considering all traits analyzed, the geographical patterns of resource allocation by Aleppo pine suggest ecotypic specialization for either resource-poor (favoring early reproduction) or resource-rich (favoring vegetative growth) habitats.

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