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1.
Plant Biol (Stuttg) ; 20(3): 555-562, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29330903

RESUMO

The development of different pollen morphs by one specimen - pollen heteromorphism - occurs in ca. one-third species of the genus Viola. Melanium section species (pansies) stand out in producing the widest range of apertures among Viola species. Aperture number decreases with elevation increase, and faster germination of five-aperturate pollen as compared with three-aperturate has previously been postulated. We re-examined pollen heteromorphism in the context of its viability, and made correlations with elevation (>1500 m a.s.l. versus <1500 m a.s.l.), soil type (metalliferous versus non-metalliferous; MET versus NMET) and chromosome number based on selected study criteria of ca. 20% karyologically and morphologically strongly differentiated but genetically closely related pansies. A total of 79% of analysed species were heteromorphic, forming three- to six-colp or ate pollen per individual flower. Mean aperture number and pollen viability were not affected by soil type (MET versus NMET). Mean aperture number was also not influenced by elevation or species chromosome number. Positive correlations were established between aperture number and pollen viability, negative between pollen viability and elevation (increasing altitude of 100 m decreased pollen viability by 0.4%) and lack of correlation between chromosome number and pollen viability. The varied frequencies of different pollen morphs among species are not under the general pressure of ecological conditions, as previously postulated for the species of Melanium section. Rather, this trait in pansies, similar to other floral characters (e.g. long, curved nectar spur, 'landing platform', posterior petals with nectar guides), is adaptive but dependent on the breeding system (inbreeding versus outbreeding) of the individual species.


Assuntos
Pólen/ultraestrutura , Viola/ultraestrutura , Altitude , Meio Ambiente , Hibridização Genética/fisiologia , Endogamia , Microscopia Eletrônica de Varredura , Reprodução/fisiologia , Solo , Viola/genética , Viola/fisiologia
2.
Plant Biol (Stuttg) ; 19(4): 542-551, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28402054

RESUMO

Viola reichenbachiana (2n = 4x = 20) and V. riviniana (2n = 8x = 40) are closely related species widely distributed in Europe, often sharing the same habitat throughout their overlapping ranges. It has been suggested in numerous studies that their high intraspecific morphological variability and plasticity might have been further increased by interspecific hybridisation in contact zones, given the sympatry of the species and the incomplete sterility of their hybrid. The aims of this study were to: (i) confirm that V. reichenbachiana and V. riviniana have one 4x genome in common, and (ii) determine the impact of hybridisation and introgression on genetic variation of these two species in selected European populations. For our study, we used 31 Viola populations from four European countries, which were analysed using AFLP and sequencing of a variable plastid intergenic spacer, trnH-psbA. Our analysis revealed that V. reichenbachiana exhibited larger haplotype diversity, having three species-specific haplotypes versus one in V. riviniana. The relationships among haplotypes suggest transfer of common haplotypes into V. riviniana from both V. reichenbachiana and hypothetically the other, now extinct, parental species. AFLP analysis showed low overall genetic diversity of both species, with V. riviniana showing higher among-population diversity. None of the morphologically designated hybrid populations had additive AFLP polymorphisms that would have indicated recent hybridisation. Also, kinship coefficients between both species did not indicate gene flow. V. riviniana showed significant population subdivision and significant isolation by distance, in contrast to V. reichenbachiana. The results indicate lack of gene flow between species, high influence of selfing on genetic variability, as well as probably only localised introgression toward V. riviniana.


Assuntos
Fluxo Gênico/genética , Viola/genética , Violaceae/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Ecossistema , Variação Genética/genética , Haplótipos/genética , Proteínas de Plantas/genética , Polimorfismo Genético/genética
3.
Eur J Neurol ; 22(2): 395-401, e28-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25370815

RESUMO

BACKGROUND AND PURPOSE: Stroke is an important cause of death and disability throughout the world. Microparticles play a cardinal role in vascular hemostasis. The primary aim of this study was to evaluate the procoagulant activity of microparticles and levels of tissue-factor-bearing microparticles (MPs-TF), tissue factor (TF) and tissue factor pathway inhibitor (TFPI) in patients with acute ischaemic stroke. METHODS: Seventy-three patients with a diagnosis of acute ischaemic stroke were included. Venous blood samples were drawn on the first day and the seventh day after stroke onset. Plasma microparticles, MPs-TF, TF and TFPI were determined by enzyme-linked immunosorbent assay. Assessment variables were timing of blood collection, type of stroke treatment, presence or absence of diabetes mellitus and hypertension, and scores on the National Institutes of Health Stroke Scale together with scores on the modified Rankin Scale. RESULTS: Whilst MPs-TF and TFPI levels of stroke subjects were significantly higher (median, 1.63 vs. 0.73 pg/ml; median, 114.26 vs. 78.60 ng/ml, respectively), TF levels in the plasma of stroke patients were significantly lower (median, 82.27 vs. 97.80 pg/ml) than those of healthy individuals. Lower levels of TF were detected in patients with severe stroke in comparison with patients with mild stroke. Moreover, the data also showed that in stroke patients not treated with alteplase the activity of microparticles was significantly higher 1 week after diagnosis in comparison with the activity at the time of diagnosis. CONCLUSION: Our findings suggest that patients with acute ischaemic stroke have increased generation of MPs-TF. Nevertheless, further studies are needed in order to confirm such inference.


Assuntos
Isquemia Encefálica/sangue , Micropartículas Derivadas de Células/metabolismo , Lipoproteínas/metabolismo , Acidente Vascular Cerebral/sangue , Tromboplastina/metabolismo , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos
4.
Plant Biol (Stuttg) ; 16(5): 924-34, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24400923

RESUMO

Morphological characters, AFLP markers and flow cytometry were used to investigate the morphological and genetic variability and differentiation of Viola reichenbachiana and V. riviniana in non-metallicolous (NM) and metallicolous (M) populations. The aims were to clarify the taxonomic status of plants occurring in ore-bearing areas, to determine any relationship in V. reichenbachiana and V. riviniana from sites not polluted with heavy metals, and to examine the genetic variability and differentiation of M and NM populations of both species. Multivariate analyses based on morphological characters showed significant differences between V. reichenbachiana and V. riviniana from non-polluted sites, high levels of intra- and inter-population variability, and the occurrence of inter-specific hybrids. Plants from M populations showed hybrid characters but also fell within the range of V. riviniana or V. reichenbachiana. There were no significant differences in relative genome size between plants from polluted areas and V. riviniana from NM populations. Bayesian analysis of population genetic structure based on AFLP markers distinguished two main groups: V. reichenbachiana and V. riviniana together with the M populations. That analysis also revealed the occurrence of populations of inter-specific hybrids from non-polluted areas. Further Bayesian analysis of V. riviniana including NM and M populations separated all the studied M populations from NM populations. We conclude that plants forming the M populations are well adapted to a metal-polluted environment, and could be considered as stabilised introgressive forms resulting from unidirectional (asymmetric) introgression toward V. riviniana.


Assuntos
Variação Genética , Metais Pesados/análise , Solo/química , Viola/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , DNA de Plantas/química , Citometria de Fluxo , Marcadores Genéticos , Metais Pesados/metabolismo , Mineração , Análise Multivariada , Filogenia , Polônia , Poluentes do Solo/metabolismo , Viola/anatomia & histologia , Viola/metabolismo
5.
J Plant Physiol ; 168(11): 1191-9, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21492955

RESUMO

Violets of the sections Melanium were examined for their colonization by arbuscular mycorrhizal fungi (AMF). Heartsease (Viola tricolor) from several heavy metal soils was AMF-positive at many sites but not at extreme biomes. The zinc violets Viola lutea ssp. westfalica (blue zinc violet) and ssp. calaminaria (yellow zinc violet) were always AMF-positive on heavy metal soils as their natural habitats. As shown for the blue form, zinc violets germinate independently of AMF and can be grown in non-polluted garden soils. Thus the zinc violets are obligatorily neither mycotrophs nor metalophytes. The alpine V. lutea, likely ancestor of the zinc violets, was at best poorly colonized by AMF. As determined by atomic absorption spectrometry, the contents of Zn and Pb were lower in AMF colonized plants than in the heavy metal soils from where the samples had been taken. AMF might prevent the uptake of toxic levels of heavy metals into the plant organs. Dithizone staining indicated a differential deposition of heavy metals in tissues of heartsease. Leaf hairs were particularly rich in heavy metals, indicating that part of the excess of heavy metals is sequestered into these cells.


Assuntos
Metais Pesados/metabolismo , Micorrizas/crescimento & desenvolvimento , Folhas de Planta/química , Raízes de Plantas/química , Viola/microbiologia , Análise de Variância , Ditizona/metabolismo , Germinação , Metais Pesados/análise , Raízes de Plantas/microbiologia , Caules de Planta/química , Microbiologia do Solo , Poluentes do Solo/análise , Poluentes do Solo/metabolismo , Espectrofotometria Atômica , Viola/química , Viola/crescimento & desenvolvimento
6.
Chemosphere ; 83(4): 435-42, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21262522

RESUMO

Changes in DNA sequences affecting cryptic intraspecific variability are very important mechanisms of plant microevolutionary processes, initiating species diversification. In polluted environments, intra- and interpopulation changes at the molecular level proceed rapidly and lead to the formation of new ecotypes in a relatively short time. We used ISSR PCR fingerprinting data to analyze the genetic diversity and genetic structure of seven populations of Viola tricolor: four growing on soil contaminated with heavy metals (Zn, Pb, Cd; waste heaps) and three from control soil. The populations from the polluted sites showed higher genetic polymorphism (%(poly)=84%) and gene diversity (H(T)=0.1709) than the control populations (%(poly)=75% and H(T)=0.1448). The number of private markers we detected within metallicolous (MET) populations was more than double that found within non-metallicolous (NON) populations (15 vs. 7). The STRUCTURE and UPGMA analyses showed clear genetic differences between the NON and MET populations. Based on broad analyses of the genetic parameters, we conclude that the effect of these polluted environments on the genetic diversity of the MET populations, separating them from the NON populations, is evidence of microevolutionary processes at species level, leading to species divergence and the emergence of local ecotypes better adapted to their different environments.


Assuntos
Variação Genética/efeitos dos fármacos , Metais/toxicidade , Poluentes do Solo/toxicidade , Viola/efeitos dos fármacos , Adaptação Fisiológica , Marcadores Genéticos , Genética Populacional , Viola/genética , Viola/fisiologia
7.
Z Orthop Ihre Grenzgeb ; 140(5): 492-8, 2002.
Artigo em Alemão | MEDLINE | ID: mdl-12226771

RESUMO

AIM: The expert evidence of operated patients with idiopathic scoliosis is determined by functional and pulmonary restriction. The degree of deformity and the extent of fusion is crucial for grading disability. In a retrospective study on the quality of life (SF-36) and low back pain (Roland-Morris Score) of 82 patients (22 - 40 years) with idiopathic scoliosis treated with Harrington instrumentation the grading was registered. METHOD: An average of 16.7 years after the surgery, these data were correlated with the type and size of curve and to the extension of fusion. RESULTS: Compared to the age-matched healthy population, there was no significant difference in the physical SF-36 scale (P = 0.98). Surgically treated patients showed significantly lower scores than at baseline in the psychological SF-36 scale (P = 0.005). Sixty-five (79.3 %) of the eighty-two patients reported no or occasional back pain in the Roland Index. Five patients (6.1 %) complained of chronic back pain. 33 patients (40 %) were legally defined in their rate of disability as severely handicapped patients. The grading disability was associated with the physical SF-36 scale (P < 0.001) and the low back pain (P = 0.02). A significant correlation between the grading disability and the extent of fusion (P = 0.53) or the size of curve (p = 0.4) could not be proven. CONCLUSION: Despite good long-term outcomes, 40 % of operated treated patients with idiopathic scoliosis were legally defined as severely handicapped persons. The additional measurements of quality of life and low-back pain can improve legal assessment in orthopaedics.


Assuntos
Prova Pericial/legislação & jurisprudência , Complicações Pós-Operatórias/diagnóstico , Qualidade de Vida/legislação & jurisprudência , Escoliose/cirurgia , Fusão Vertebral , Vértebras Torácicas/cirurgia , Adolescente , Adulto , Dor nas Costas/diagnóstico , Avaliação da Deficiência , Feminino , Seguimentos , Alemanha , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Fusão Vertebral/legislação & jurisprudência
8.
Pneumonol Alergol Pol ; 65 Suppl 1: 44-50, 1997.
Artigo em Polonês | MEDLINE | ID: mdl-9410301

RESUMO

10 children 8-16 years old (mean = 12.9) received at least 4 inhalations of short acting beta-2-mimetics and up to 100 mcg inhaled corticosteroids or/and 5 mg oral prednisone daily. Lung function test values indicated mild/severe asthma in these patients (PEFF 50-80%, FEV1 50-80%, FEV1/VC less or equal 60%). Reversibility of obstruction was at least 15% comparing to the initial values. After two weeks of this treatment resolution of dyspnoea in the night-time and significant decrease of dyspnoea in the day-time were observed. The best bronchodilatation effect was noticed in the third and fourth week of therapy. After discontinuation of Serevent significantly milder course of dyspnoea was observed.


Assuntos
Albuterol/análogos & derivados , Asma/tratamento farmacológico , Broncodilatadores/uso terapêutico , Dispneia/tratamento farmacológico , Transtornos do Sono-Vigília/tratamento farmacológico , Administração por Inalação , Adolescente , Corticosteroides/administração & dosagem , Agonistas Adrenérgicos beta/administração & dosagem , Albuterol/uso terapêutico , Criança , Esquema de Medicação , Feminino , Humanos , Masculino , Prednisona/administração & dosagem , Testes de Função Respiratória , Xinafoato de Salmeterol , Resultado do Tratamento
9.
Pneumonol Pol ; 58(2-3): 129-32, 1990.
Artigo em Polonês | MEDLINE | ID: mdl-2352882

RESUMO

A case of Bruton's syndrome is presented in a 8 year old boy who was treated due to skin, and ear infections. Diagnosis of agammaglobulinemia allowed correct substantive therapy and decrease of infections.


Assuntos
Agamaglobulinemia/diagnóstico , Agamaglobulinemia/terapia , Criança , Humanos , Masculino
10.
Kinderarztl Prax ; 57(1): 23-7, 1989 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-2709687

RESUMO

Electronmicroscopy examinations of the skin vessels were performed in 20 well compensated children with insulin-dependent diabetes mellitus (14 girls and 6 boys ages from 4 to 18 years). The results were compared with 10 healthy ones. In 17 patients the electron-microscopic picture was pathologic, with varying of intensity. Structurally, the most relevant changes were represented by thickening of the basal membrane (in some cases with its multiplication), swelling of endothelial cells, decrease in number of pinocytic vesicules and presence of deposits with increased electron density in the pericarion and the perivascular space. Vascular disturbances may develop very early, sometimes in the first month after manifestation of the disease. The authors suggest, that further investigations are necessary to elucidate the nature of the observed changes. An intensification of insulin therapy would be also considered.


Assuntos
Diabetes Mellitus Tipo 1/patologia , Angiopatias Diabéticas/patologia , Endotélio Vascular/patologia , Músculo Liso Vascular/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Microscopia Eletrônica
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