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1.
J Evol Biol ; 34(9): 1503-1509, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34331325

RESUMO

High reproductive assurance is regarded as a key advantage of uniparentally reproducing organisms for establishing a new population. This demographic benefit should especially be relevant for plants with autonomous apomixis, that is those which produce seeds completely independently from mates and pollinators. Indeed, many autonomous apomicts occupy larger distributional ranges when compared to their sexual relatives, showing geographical parthenogenesis patterns. However, uniparental reproduction advantage has only rarely been quantified in natural populations and results provided a mixed support, partly because allopatric sexual and asexual populations were exposed to different environmental and pollination conditions causing considerable between-population variation in the level of reproductive assurance. Here, we compared the level and stability of reproductive assurance between sexual self-incompatible and asexual autonomously apomictic plants of Hieracium alpinum (Asteraceae) cultivated in a sympatric low-density population with two levels of spatial clumping of sexual plants. Overall, we found that the realized seed set (i.e. proportion of well-developed seeds per capitulum) of asexuals was ca. 3 times greater than that of sexuals (83% vs. 27%), whereas the variance of this trait expressed as coefficient of variation was ca. 4 times smaller in asexuals compared with sexuals (19% vs. 83%). Solitary sexual plants had more than 2 times lower realized seed set when compared to clumps composed of two spatially close (20-30 cm) sexual plants (13% vs. 34%). Our study provides experimental evidence for benefit of uniparental reproduction of asexuals in a sympatric situation when the availability of mates is limited. This, together with unpredictability of pollinator environment could provide autonomous apomicts with an ultimate demographic superiority during colonization reflected in geographical parthenogenesis observed in this species.


Assuntos
Apomixia , Apomixia/genética , Plantas , Pólen , Reprodução , Sementes , Simpatria
2.
Am J Bot ; 107(1): 66-90, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31903548

RESUMO

PREMISE: The origin of allopolyploids is believed to shape their evolutionary potential, ecology, and geographical ranges. Morphologically distinct apomictic types sharing the same parental species belong to the most challenging groups of polyploids. We evaluated the origins and variation of two triploid taxa (Hieracium pallidiflorum, H. picroides) presumably derived from the same diploid parental pair (H. intybaceum, H. prenanthoides). METHODS: We used a suite of approaches ranging from morphological, phylogenetic (three unlinked molecular markers), and cytogenetic analyses (in situ hybridization) to genome size screening and genome skimming. RESULTS: Genotyping proved the expected parentage of all analyzed accessions of H. pallidiflorum and H. picroides and revealed that nearly all of them originated independently. Genome sizes and genome dosage largely corresponded to morphology, whereas the maternal origin of the allopolyploids had no discernable effect. Polyploid accessions of both parental species usually contained genetic material from other species. Given the phylogenetic distance of the parents, their chromosomes appeared only weakly differentiated in genomic in situ hybridization (GISH), as well as in overall comparisons of the repetitive fraction of their genomes. Furthermore, the repeatome of a phylogenetically more closely related species (H. umbellatum) differed significantly more. CONCLUSIONS: We proved (1) multiple origins of hybridogeneous apomicts from the same diploid parental taxa, and (2) allopolyploid origins of polyploid accessions of the parental species. We also showed that the evolutionary dynamics of very fast evolving markers such as satellite DNA or transposable elements does not necessarily follow patterns of speciation.


Assuntos
Evolução Biológica , Poliploidia , Diploide , Genoma de Planta , Genômica , Humanos , Filogenia
3.
Iran J Pharm Res ; 18(2): 1010-1019, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31531081

RESUMO

A high prevalence of genetic polymorphisms increases sensitivity to warfarin therapy. In this study, we investigated 47 patients with effective long-term therapy by warfarin well-controlled by monitoring of International Normalised Ratio (INR). All patients were tested for gene polymorphisms VKORC1, CYP2C9*C2, and CYP2C9*C3, which were used for a dose calculation employing a program www.WarfarinDosing.org. The main goal was to investigate whether the warfarin doses determined by INR are in accordance with the doses calculated according to the pharmacogenetic algorithm. For this purpose, several chemometric tools, namely principal component analysis, cluster analysis, correlation analysis, correspondence analysis, Passing-Bablock regression, Bland-Altman method, descriptive statistics, and ANOVA were used. We also analysed the relationship between the dose of warfarin determined by INR and several constitutional and genetic factors. Statistically significant association between clinically optimized warfarin dose and indication for the treatment, age, and warfarin sensitivity determined by VKORC1, CYP2C9 gene polymorphisms were confirmed. Finally, we confirmed a good concordance between the INR determined warfarin doses and pharmacogenetic approach.

4.
Int J Biol Markers ; 33(2): 231-236, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29712495

RESUMO

Non-alcoholic steato-hepatitis (NASH) is a severe disease characterised by liver inflammation and progressive hepatic fibrosis, which may progress to cirrhosis and hepatocellular carcinoma. Clinical evidence suggests that in hepatitis C virus patients steatosis and NASH are associated with faster fibrosis progression and hepatocellular carcinoma. A safe and reliable non-invasive diagnostic method to detect NASH at its early stages is still needed to prevent progression of the disease. We prospectively enrolled 91 hepatitis C virus-positive patients with histologically proven chronic liver disease: 77 patients were included in our study; of these, 10 had NASH. For each patient, various clinical and serological variables were collected. Different algorithms combining squamous cell carcinoma antigen-immunoglobulin-M (SCCA-IgM) levels with other common clinical data were created to provide the probability of having NASH. Our analysis revealed a statistically significant correlation between the histological presence of NASH and SCCA-IgM, insulin, homeostasis model assessment, haemoglobin, high-density lipoprotein and ferritin levels, and smoke. Compared to the use of a single marker, algorithms that combined four, six or seven variables identified NASH with higher accuracy. The best diagnostic performance was obtained with the logistic regression combination, which included all seven variables correlated with NASH. The combination of SCCA-IgM with common clinical data shows promising diagnostic performance for the detection of NASH in hepatitis C virus patients.


Assuntos
Antígenos de Neoplasias/sangue , Hepatite C/sangue , Imunoglobulina M/sangue , Hepatopatia Gordurosa não Alcoólica/sangue , Serpinas/sangue , Adulto , Algoritmos , Biomarcadores Tumorais/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Hepatite C/complicações , Hepatite C/patologia , Hepatite C/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/virologia
5.
J Pharm Biomed Anal ; 50(2): 210-5, 2009 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-19467816

RESUMO

Diagnosis of lung malignity can be predicted or confirmed not only according to the values of appropriate laboratory tests but also using multidimensional statistical analysis, which uses simultaneously all performed tests in the form of their optimal combination. The developed new way of diagnosis prediction is applied here to the results of laboratory analysis of lung tumor markers in serum as well as pleural effusion (exudate). Four laboratory tests were used and investigated in detail: carcinoembryonic antigen, CEA, in serum as well as in pleural exudate, and cytokeratin 19 fragment, CYFRA, in serum and exudate, as well. Each test represents one dimension in the investigated biomedical problem from the statistical point of view. Joint utilization of the performed laboratory tests is based on their optimized combination into a new statistical variable using a selected chemometric principle (principal component, discriminant function, or logit in logistic regression). This approach results in enhancement of diagnostic effectiveness applied for the specified purpose.


Assuntos
Neoplasias Pulmonares/diagnóstico , Análise de Variância , Antígenos de Neoplasias/sangue , Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/metabolismo , Antígeno Carcinoembrionário/sangue , Antígeno Carcinoembrionário/metabolismo , Análise por Conglomerados , Humanos , Queratina-19/sangue , Queratina-19/metabolismo , Neoplasias Pulmonares/patologia , Redes Neurais de Computação , Derrame Pleural/metabolismo , Curva ROC
6.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 5): m610-1, 2008 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-21202169

RESUMO

In the title compound, [Cu(C(2)H(2)ClO(2))(2)(C(8)H(7)NO)(2)(CH(4)O)], the Cu(2+) ion has a highly distorted square-bipyramidal (4 + 1 + 1) coordination environment and is bonded to three carboxyl-ate O atoms of two chloro-acetate anions (monodentate and asymmetrically bidentate), two pyridine N atoms of 2-methyl-furo[3,2-c]pyridine and one methanol O atom. There is an intra-molecular O-H⋯O hydrogen bond. Inter-molecular C-H⋯O hydrogen bonds result in the formation of a three-dimensional network and π-π stacking inter-actions [3.44-3.83 Å] are observed between symmetry-related rings of 2-methyl-furo[3,2-c]pyridine. Further inter-actions in the crystal structure are a short Cl⋯Cl inter-action [3.384 (2)Å] and C-H⋯π inter-actions between 2-methyl-furo[3,2-c]pyridine rings.

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