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1.
Glob Chang Biol ; 20(5): 1498-511, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24273066

RESUMO

A transnational network of genetic conservation units for forest trees was recently documented in Europe aiming at the conservation of evolutionary processes and the adaptive potential of natural or man-made tree populations. In this study, we quantified the vulnerability of individual conservation units and the whole network to climate change using climate favourability models and the estimated velocity of climate change. Compared to the overall climate niche of the analysed target species populations at the warm and dry end of the species niche are underrepresented in the network. However, by 2100, target species in 33-65 % of conservation units, mostly located in southern Europe, will be at the limit or outside the species' current climatic niche as demonstrated by favourabilities below required model sensitivities of 95%. The highest average decrease in favourabilities throughout the network can be expected for coniferous trees although they are mainly occurring within units in mountainous landscapes for which we estimated lower velocities of change. Generally, the species-specific estimates of favourabilities showed only low correlations to the velocity of climate change in individual units, indicating that both vulnerability measures should be considered for climate risk analysis. The variation in favourabilities among target species within the same conservation units is expected to increase with climate change and will likely require a prioritization among co-occurring species. The present results suggest that there is a strong need to intensify monitoring efforts and to develop additional conservation measures for populations in the most vulnerable units. Also, our results call for continued transnational actions for genetic conservation of European forest trees, including the establishment of dynamic conservation populations outside the current species distribution ranges within European assisted migration schemes.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Florestas , Árvores/fisiologia , Europa (Continente) , Modelos Biológicos , Especificidade da Espécie , Árvores/genética
2.
Conserv Biol ; 27(2): 373-84, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23240629

RESUMO

Dynamic conservation of forest genetic resources (FGR) means maintaining the genetic diversity of trees within an evolutionary process and allowing generation turnover in the forest. We assessed the network of forests areas managed for the dynamic conservation of FGR (conservation units) across Europe (33 countries). On the basis of information available in the European Information System on FGR (EUFGIS Portal), species distribution maps, and environmental stratification of the continent, we developed ecogeographic indicators, a marginality index, and demographic indicators to assess and monitor forest conservation efforts. The pan-European network has 1967 conservation units, 2737 populations of target trees, and 86 species of target trees. We detected a poor coincidence between FGR conservation and other biodiversity conservation objectives within this network. We identified 2 complementary strategies: a species-oriented strategy in which national conservation networks are specifically designed for key target species and a site-oriented strategy in which multiple-target units include so-called secondary species conserved within a few sites. The network is highly unbalanced in terms of species representation, and 7 key target species are conserved in 60% of the conservation units. We performed specific gap analyses for 11 tree species, including assessment of ecogeographic, demographic, and genetic criteria. For each species, we identified gaps, particularly in the marginal parts of their distribution range, and found multiple redundant conservation units in other areas. The Mediterranean forests and to a lesser extent the boreal forests are underrepresented. Monitoring the conservation efficiency of each unit remains challenging; however, <2% of the conserved populations seem to be at risk of extinction. On the basis of our results, we recommend combining species-oriented and site-oriented strategies.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Variação Genética , Árvores/genética , Europa (Continente) , Especificidade da Espécie
3.
Cutis ; 71(1): 59-61, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12553631

RESUMO

Mycosis fungoides is a cutaneous T-cell lymphoma. Its presence, which denotes an altered immune system, may make treatment of otherwise simple cutaneous infections difficult. In the case presented here, a patient with widespread tinea corporis poorly responsive to several oral antifungals was noted as having a background poikilodermatous slightly scaly eruption. Results of a skin biopsy during therapy with oral antifungal medications showed evidence of tinea corporis; atrophy of the epidermis; a superficial, perivascular, and interstitial lymphocytic infiltrate with numerous atypical lymphocytes; and exocytosis of atypical lymphocytes into the epidermis with formation of microabscesses-findings consistent with the diagnosis of mycosis fungoides. Treatment with PUVA (oral psoralen and UVA light) and oral itraconazole led to long-term remission of the mycosis fungoides and the associated tinea corporis. Immune suppression may have contributed to the recalcitrant nature of our patient's dermatophyte infection. Underlying cutaneous, systemic, or iatrogenic disorders associated with immune dysfunction should be considered in patients with recalcitrant dermatophyte infections.


Assuntos
Micose Fungoide/complicações , Micose Fungoide/patologia , Neoplasias Cutâneas/complicações , Neoplasias Cutâneas/patologia , Tinha/etiologia , Tinha/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Micose Fungoide/terapia , Neoplasias Cutâneas/terapia , Tinha/terapia
4.
Pediatr Dermatol ; 19(6): 550-2, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12437562

RESUMO

Incontinentia pigmenti is a rare disorder that may affect many systems including the skin, central nervous system, bone, and eyes. We describe a 13-day-old girl who developed seizures on day 1 of life and was placed on antiseizure medication. On approximately day 4 of life, she developed a vesicular rash on her trunk and extremities. The pediatric team prescribed intravenous acyclovir and diphenhydramine cream. These were used without improvement. At dermatology consultation, linear and swirled vesicular lesions were seen. A skin biopsy specimen revealed eosinophils within intraepidermal vesicles consistent with a diagnoses of incontinentia pigmenti. This case of incontinentia pigmenti is of interest in that the initial symptom was a seizure disorder.


Assuntos
Incontinência Pigmentar/diagnóstico , Anticonvulsivantes/uso terapêutico , Diagnóstico Diferencial , Feminino , Aconselhamento Genético , Humanos , Incontinência Pigmentar/complicações , Recém-Nascido , Convulsões/tratamento farmacológico , Convulsões/etiologia
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