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1.
Plant Biol (Stuttg) ; 19(1): 46-52, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27094365

RESUMO

We analysed the effects of summer temperatures (28/14 °C) and/or desiccation (from 48% to 8% humidity) on imbibed Narcissus alcaracensis and N. longispathus seeds with an elongating embryo. In the N. alcaracensis seeds that overcame dormancy (embryo elongation = 27.14%), exposure to high temperatures induced secondary dormancy and reduced subsequent embryo growth. A further 3-month cold stratification (5 °C) was required to break secondary dormancy. Desiccation in early embryo growth stages (elongation = 11.42%) also reduced germination. Desiccation in the seeds in a more advanced growth stage (i.e. embryo elongation = 27.14%) induced secondary dormancy, which the further 3-month cold stratification did not overcome. When desiccation was preceded by high temperatures, seeds better overcame secondary dormancy (i.e. longer embryo elongation and seed germination). Treatments did not affect seed viability. In the N. longispathus seeds that overcame dormancy (embryo elongation = 59.21%), exposure to high temperatures induced secondary dormancy and they needed a further 1-month stratification at 15/4 °C + 2 months at 5 °C to reactivate the germination process. When embryo elongation was 42.10%, seed desiccation totally impeded subsequent germination. When embryo elongation reached 59.21%, desiccation induced secondary dormancy, which was not overcome by the above-described stratification treatment. When desiccation was preceded by high temperatures, seeds better overcame dormancy. Stress treatments killed 5-10% of seeds. This study suggests that the seeds of species with complex morphophysiological dormancy (MPD) levels are sensitive to desiccation in early embryo development stages, as opposed to the seeds of species with deep simple epicotyl MPD, which better tolerate water stress.


Assuntos
Narcissus/fisiologia , Dormência de Plantas , Sementes/fisiologia , Temperatura Baixa , Dessecação , Germinação , Temperatura Alta , Umidade , Estações do Ano , Temperatura
2.
Plant Biol (Stuttg) ; 17(4): 798-807, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25598169

RESUMO

The germination ecology of Sideritis serrata was investigated in order to improve ex-situ propagation techniques and management of their habitat. Specifically, we analysed: (i) influence of temperature, light conditions and seed age on germination patterns; (ii) phenology of germination; (iii) germinative response of buried seeds to seasonal temperature changes; (iv) temperature requirements for induction and breaking of secondary dormancy; (v) ability to form persistent soil seed banks; and (vi) seed bank dynamics. Freshly matured seeds showed conditional physiological dormancy, germinating at low and cool temperatures but not at high ones (28/14 and 32/18 °C). Germination ability increased with time of dry storage, suggesting the existence of non-deep physiological dormancy. Under unheated shade-house conditions, germination was concentrated in the first autumn. S. serrata seeds buried and exposed to natural seasonal temperature variations in the shade-house, exhibited an annual conditional dormancy/non-dormancy cycle, coming out of conditional dormancy in summer and re-entering it in winter. Non-dormant seeds were clearly induced into dormancy when stratified at 5 or 15/4 °C for 8 weeks. Dormant seeds, stratified at 28/14 or 32/18 °C for 16 weeks, became non-dormant if they were subsequently incubated over a temperature range from 15/4 to 32/18 °C. S. serrata is able to form small persistent soil seed banks. The maximum seed life span in the soil was 4 years, decreasing with burial depth. This is the second report of an annual conditional dormancy/non-dormancy cycle in seeds of shrub species.


Assuntos
Germinação/fisiologia , Dormência de Plantas/fisiologia , Sideritis/fisiologia , Ecologia , Ecossistema , Estações do Ano , Sementes/fisiologia , Solo , Temperatura
3.
Actas Dermosifiliogr ; 102(2): 132-41, 2011 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-21377137

RESUMO

BACKGROUND AND OBJECTIVES: The Working Group on Psoriasis of the Spanish Academy of Dermatology and Venereology has initiated BIOBADADERM, a registry of patients with psoriasis receiving treatment with biologic drugs, in order to assess the long-term risk of adverse events (AEs). MATERIAL AND METHODS: A multicenter study was undertaken in 2 cohorts of patients with psoriasis: patients receiving biologic therapy and patients receiving nonbiologic systemic therapy other than phototherapy. Similar numbers of patients were included in each group. Information was recorded on demographic and clinical variables, treatment, and relevant AEs. The risk of specific AEs was determined by comparison of the frequencies for those events in the 2 cohorts. RESULTS: Data on the 2 cohorts were evaluated for the period from October, 2008 to November, 2009 alongside retrospective data on patients treated with biologics since 2005. Thirteen Spanish hospitals participated in the study. A total of 632 patients were included in the analysis: 417 treated with biologic drugs and 215 controls. Suspension of biologic therapy due to AEs was rare (72 cycles, 10%). A total of 232 AEs were reported in patients receiving biologic therapy. The majority were not serious. The most frequent AEs were infections (mostly upper respiratory tract infections and nasopharyngitis), followed by conditions affecting the skin or subcutaneous tissue. Forty-three AEs were reported in control subjects. The most frequent events were metabolic and nutritional abnormalities and abnormal transaminase levels. Comparison of the incidence of any AE in patients treated with biologics compared with control subjects revealed a relative risk of 2.2 (P<.001) The relative risks of infections or infestations and disorders of the skin or subcutaneous tissue in patients receiving biologic drugs were 23 (P<.01) and 4.9 (P<.05), respectively. CONCLUSIONS: Patients treated with biologic drugs had a greater number of AEs, particularly infections and skin conditions. Definitive conclusions, however, are difficult to draw due to the small number of patients included in the registry, particularly in the control cohort, and the short follow-up period. Differences in the percentages of events reported by the different hospitals reveal the difficulties associated with the concept of AEs in clinical practice and highlight the need to harmonize criteria in the future. Since the problems identified in this analysis should be overcome in future years, we expect BIOBADADERM to become an important source of information on the safety profile of biologic drugs in dermatology.


Assuntos
Produtos Biológicos/efeitos adversos , Psoríase/tratamento farmacológico , Sistema de Registros , Produtos Biológicos/uso terapêutico , Estudos de Coortes , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Espanha
4.
Actas Dermosifiliogr ; 102(1): 28-38, 2011 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-21315859

RESUMO

BACKGROUND AND OBJECTIVES: the aim of this study was to design and assess the validity, reliability, and sensitivity to change of the Spanish Satisfaction With Treatment of Psoriasis Questionnaire (SSTPQ) for use in patients with moderate-to-severe psoriasis. PATIENTS AND METHODS: a prospective, multicenter, observational, naturalistic study was designed. The instrument consisted of 12 items scored on a 5-point Likert scale with scores from 0 (very satisfied) to 5 (very unsatisfied), generating a total score of 0 to 48. Patients completed the questionnaire at baseline and then at 3-, 6-, 9-, and 12-month follow-up. At each visit, data were also collected on the Psoriasis Area and Severity Index (PASI), treatment adherence (Morisky-Green questionnaire), and overall treatment satisfaction on a Visual Analogue Scale (VAS) from 0 to 100. RESULTS: a total of 423 patients were included in the study and 68% completed 12 months of follow-up. Responses were provided to all items in 98.8% of cases. There was a weak correlation between changes in treatment satisfaction on the SSTPQ and changes in PASI score (r = 0.38 to 0.33); in contrast, there were strong correlations with changes in the VAS score for overall treatment satisfaction (r = -0.75 to -0.81). Good internal consistency was observed (Cronbach α = 0.92). The intraclass correlation coefficient was 0.89, with a mean difference in score at 3- and 6-month follow-up of 0.07. CONCLUSIONS: The results obtained suggest that the SSTPQ is a feasible, valid, and reliable tool for the assessment of treatment satisfaction in patients with moderate-to-severe psoriasis.


Assuntos
Satisfação do Paciente , Psoríase/psicologia , Inquéritos e Questionários , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Comorbidade , Fármacos Dermatológicos/uso terapêutico , Feminino , Seguimentos , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Visita a Consultório Médico , Fotoquimioterapia , Psoríase/tratamento farmacológico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Espanha , Adulto Jovem
5.
An Pediatr (Barc) ; 72(4): 282.e1-9, 2010 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-20053592

RESUMO

Children are one of the population groups in which the photo-protection must be maximised. Firstly, because they take part in outdoor activities more often than adults. Secondly, because the principal risk factor for all types of skin cancer is ultraviolet radiation, and in particular, cumulative exposure during childhood. Hence, decreasing exposure to ultraviolet radiation in childhood has the potential to significantly lower the incidence of most forms of skin cancer. Photoprotection includes behavioural measures to protect the skin from sun exposure, e.g. sun protective clothes, hats, sunglasses, and sunscreens. It is necessary to provide information on aphotoprotection to parents, and, above all, to children, using educational campaigns to increase knowledge of photoprotection to help change attitudes towards sun exposure. Dermatologists and Paediatricians play a essential role in this educational work. In this article we review the latest information regarding paediatric sun protection, the new sunscreens, and the recent sun protection educational programs.


Assuntos
Proteção Radiológica/métodos , Protetores Solares , Criança , Educação em Saúde , Humanos , Neoplasias Cutâneas/prevenção & controle
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