Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Assunto da revista
País de afiliação
Intervalo de ano de publicação
1.
BMC Plant Biol ; 21(1): 383, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34416875

RESUMO

BACKGROUND: One of the major trends in angiosperm evolution was the shift from woody to herbaceous habit. However, reversals known as derived woodiness have also been reported in numerous, distantly related clades. Among theories evoked to explain the factors promoting the evolution of derived woodiness are moderate climate theory and cavitation theory. The first assumes that woody habit evolves in response to mild climate allowing for prolonged life span, which in turn leads to bigger and woodier bodies. The second sees woodiness as a result of natural selection for higher cavitation resistance in seasonally dry environments. Here, we compare climatic niches of woody and herbaceous, mostly southern African, umbellifers from the Lefebvrea clade to assess whether woody taxa in fact occur in markedly drier habitats. We also calibrate their phylogeny to estimate when derived woodiness evolved. Finally, we describe the wood anatomy of selected woody and herbaceous taxa to see if life forms are linked to any particular wood traits. RESULTS: The evolution of derived woodiness in chamaephytes and phanerophytes as well as the shifts to short-lived annual therophytes in the Lefebvrea clade took place at roughly the same time: in the Late Miocene during a trend of global climate aridification. Climatic niches of woody and herbaceous genera from the Cape Floristic Region overlap. There are only two genera with distinctly different climatic preferences: they are herbaceous and occur outside of the Cape Floristic Region. Therefore, studied herbs have an overall climatic niche wider than their woody cousins. Woody and herbaceous species do not differ in qualitative wood anatomy, which is more affected by stem architecture and, probably, reproductive strategy than by habit. CONCLUSIONS: Palaeodrought was likely a stimulus for the evolution of derived woodiness in the Lefebvrea clade, supporting the cavitation theory. The concurrent evolution of short-lived annuals withering before summer exemplifies an alternative solution to the same problem of drought-induced cavitation. Changes of the life form were most likely neither spurred nor precluded by any qualitative wood traits, which in turn are more affected by internode length and probably also reproductive strategy.


Assuntos
Adaptação Fisiológica/genética , Adaptação Fisiológica/fisiologia , Apiaceae/anatomia & histologia , Apiaceae/crescimento & desenvolvimento , Apiaceae/genética , Evolução Biológica , Secas , Madeira/anatomia & histologia , Variação Genética , Genótipo , Filogenia
2.
Am J Bot ; 107(3): 394-412, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32147817

RESUMO

PREMISE: Despite intensive research, the pathways and driving forces behind the evolution of derived woodiness on oceanic islands remain obscure. The genus Daucus comprises mostly herbs (therophytes, hemicryptophytes) with few rosette treelets (chamaephytes) endemic to various Macaronesian archipelagos, suggesting their independent evolution. To elucidate the evolutionary pathways to derived woodiness, we examined phylogenetic relationships and the habit and secondary xylem evolution in Daucus and related taxa. METHODS: Sixty taxa were surveyed for molecular markers, life history, and habit traits. Twenty-one species were considered for wood anatomical characters. A dated phylogeny was estimated using Bayesian methods. The evolution of selected traits was reconstructed using parsimony and maximum likelihood. RESULTS: Daucus dispersed independently to the Canary Islands (and subsequently to Madeira), Cape Verde, and the Azores in the late Miocene and Pleistocene. Life span, reproductive strategy, and life form were highly homoplastic; the ancestor of Daucus was probably a monocarpic, biennial hemicryptophyte. Rosette treelets evolved independently in the Canarian-Madeiran lineage and in Cape Verde, the latter within the last 0.13 Myr. Treelets and hemicryptophytes did not differ in wood anatomy. Pervasive axial parenchyma in wood occurred more often in polycarpic rather than monocarpic species. CONCLUSIONS: Life span and life form in Daucus are evolutionarily labile and may change independently of wood anatomy, which is related to plant reproductive strategy rather than to life form. Insular woodiness may evolve rapidly (as demonstrated in D. bischoffii), and in Daucus, it does not seem to be an adaptation to lower the risk of xylem embolism.


Assuntos
Daucus carota , Açores , Teorema de Bayes , Filogenia , Portugal , Espanha
3.
Postepy Dermatol Alergol ; 33(5): 323-328, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27881936

RESUMO

Autologous fat transfer (AFT) is an appropriate technique for aesthetic rejuvenation of the face, aesthetic enhancement of hands, correction of the facial appearance in various disorders and constitutes a surgical alternative of treatment of numerous breast deformities ranging from distorting posttraumatic scars, post-eczema lesions, post-burn deformities to partial or total breast reconstruction. Our work is aimed to familiarize dermatologists with the technique of harvesting and implanting the aspirate of adipose cells in patients consulted for deformities of the breast. In addition, the review summarizes the most common applications of AFT in the breast reconstructive procedures. In summary, AFT is an oncologically safe, relatively complication-free, minimally invasive surgical technique, which can be used to correct a wide range of deformities, which are commonly seen by dermatologists, in the area of the face, trunk and extremities. The procedure can correct a wide range of breast deformities, from contour or single quadrant deformities up to the state after mastectomy.

5.
Parasit Vectors ; 13(1): 95, 2020 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-32087754

RESUMO

BACKGROUND: Rodents constitute an important part of the diet of many carnivore species. This predator-prey food chain is exploited by helminth parasites, such as cestodes, whose larval stages develop in rodents and then mature to the adult stage in predators. The main aim of our study was to use molecular techniques for identification of cestode species recovered from both intermediate and definitive hosts, with a particular focus on the genus Mesocestoides. METHODS: Larval cestodes were obtained during our long-term studies on rodent helminth communities in the Mazury Lake District in the north-east Poland in 2000-2018. Cestode larvae/cysts were collected from body cavities or internal organs (e.g. liver) during autopsies. Adult tapeworms were derived from nine red foxes, three Eurasian badgers and one Eurasian lynx. PCR amplification, sequencing and phylogenetic analyses were conducted employing three genetic markers: 18S rDNA, mitochondrial (mt) 12S rDNA and the mt cytochrome c oxydase subunit 1 (cox1) gene fragment. RESULTS: Altogether 19 Mesocestoides samples were analyzed, including 13 adult tapeworms from definitive hosts and six larval samples from 4 bank voles and 2 yellow-necked mice. Phylogenetic analyses revealed three well-supported trees of similar topology. In each case the Mesocestoides samples formed two separate clades. All isolates from foxes, the lynx isolate and two isolates from rodents grouped with Mesocestoides litteratus. Four isolates from rodents and all three isolates from Eurasian badgers were resolved in a separate clade, most similar to North American M. vogae (syn. M. corti). Examination of fixed, stained adult specimens from Eurasian badgers revealed consistency with the morphology of Mesocestoides melesi. Therefore, this clade is likely to represent M. melesi, a species first described in 1985 from the Eurasian badger Meles meles. Molecular analysis allowed also the identification of Taenia crassiceps, Hydatigera kamiyai and Cladotaenia globifera among larvae derived from rodents. CONCLUSIONS: Molecular and phylogenetic analyses support the recognition of M. melesi as a valid species. Our data represent the first record of the larvae of this species in rodents. This is the first report on the occurrence of H. kamiyai in rodents from Poland.


Assuntos
Carnívoros/parasitologia , Infecções por Cestoides/veterinária , Reservatórios de Doenças/veterinária , Mesocestoides/fisiologia , Roedores/parasitologia , Animais , Infecções por Cestoides/parasitologia , Infecções por Cestoides/transmissão , Reservatórios de Doenças/classificação , Reservatórios de Doenças/parasitologia , Raposas/parasitologia , Estágios do Ciclo de Vida , Mesocestoides/genética , Mesocestoides/crescimento & desenvolvimento , Mesocestoides/isolamento & purificação , Filogenia , Polônia , Roedores/classificação
6.
Data Brief ; 23: 103779, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31372426

RESUMO

Aureoboletus projectellus is a bolete species native to eastern North America, which has been introduced to Central Europe. Here we present summarized data about occurrence of the fungus in both disjunctive ranges based on (1) de novo georeferencing of herbarium specimens and occurrence reports; (2) information from peer-reviewed articles, mycological forums and websites; (3) personal observations and (4) from queries sent to Forest Districts and National Parks in Poland. Corresponding background data were acquired from public databases and include range of genus Pinus - obligatory mycorrhizal partner of A. projectellus - and WorldClim bioclimatic data. Both datasets were fit for purpose of range modelling, i.e. were represented as spatially compatible equal-area raster grids encompassing temperate forest biom in eastern North America and Europe. Additionally, maps of habitat suitability, reflecting association between occurrence and background data, were obtained using maximum entropy approach implemented in MaxEnt.

7.
Acta Biochim Pol ; 65(4): 573-571, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30440055

RESUMO

Although loss of bone mineral density is a common symptom of chronic inflammatory diseases, its mechanisms are still poorly understood. The PHEX gene encodes a Zn-endopeptidase expressed in osteoblasts and contributes to bone mineralization. Data derived from rodents has indicated co-repression of the PHEX gene by the NF-κB pathway and poly(ADP-ribose) polymerase 1 (PARP1). The aim of this study was to determine the molecular mechanism involved in TNF-mediated downregulation of PHEX expression in human osteoblasts and human osteosarcoma cell line. We observed that activation of the NF-κB pathway by TNF was manifested as a nuclear increase in RELA and NFKB1 heterodimer. We found that TNF reduced PHEX expression and the proteasome inhibitor reversed this effect in osteosarcoma cell line. Contrary to the effects seen in rodents, inhibition of PARP1 enzymatic activity did not significantly reverse the effect of TNF on the human PHEX gene expression. EMSA studies showed that the number of adenines in the PHEX proximal promoter is crucial for the transcription factors' interactions within that region. The obtained results support the hypothesis indicating the existence of a molecular mechanism of gene repression that involves a poly adenine-rich region of the proximal gene promoters and PARP1 transcriptional activity.


Assuntos
Regulação da Expressão Gênica , Subunidade p50 de NF-kappa B/metabolismo , Osteoblastos/metabolismo , Endopeptidase Neutra Reguladora de Fosfato PHEX/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Calcificação Fisiológica , Linhagem Celular Tumoral , Regulação para Baixo , Expressão Gênica , Humanos , Subunidade p50 de NF-kappa B/genética , Osteoblastos/efeitos dos fármacos , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Regiões Promotoras Genéticas , Transdução de Sinais , Fator de Transcrição RelA/genética , Fator de Necrose Tumoral alfa/farmacologia
8.
Stem Cells Int ; 2018: 1049641, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30154860

RESUMO

Alopecia is caused by a variety of factors which affect the hair cycle and decrease stem cell activity and hair follicle regeneration capability. This process causes lower self-acceptance, which may result in depression and anxiety. However, an early onset of androgenic alopecia is associated with an increased incidence of the metabolic syndrome and an increased risk of the cardiac ischaemic disease. The ubiquity of alopecia provides an encouragement to seek new, more effective therapies aimed at hair follicle regeneration and neoregeneration. We know that stem cells can be used to regenerate hair in several therapeutic strategies: reversing the pathological mechanisms which contribute to hair loss, regeneration of complete hair follicles from their parts, and neogenesis of hair follicles from a stem cell culture with isolated cells or tissue engineering. Hair transplant has become a conventional treatment technique in androgenic alopecia (micrografts). Although an autologous transplant is regarded as the gold standard, its usability is limited, because of both a limited amount of material and a reduced viability of cells obtained in this way. The new therapeutic options are adipose-derived stem cells and stem cells from Wharton's jelly. They seem an ideal cell population for use in regenerative medicine because of the absence of immunogenic properties and their ease of obtainment, multipotential character, ease of differentiating into various cell lines, and considerable potential for angiogenesis. In this article, we presented advantages and limitations of using these types of cells in alopecia treatment.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA