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1.
Ecol Evol ; 13(9): e10467, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37664498

RESUMO

Progressive changes in the environment are related to modifications of the habitat. Introducing exotic species, and interbreeding between species can lead to processes that in the case of rare species or small populations threatens their integrity. Given the declining trends of many populations due to increased hybridization, early recognition of hybrids becomes important in conservation management. Natural hybridization is prevalent in Jacobaea. There are many naturally occurring interspecific hybrids in this genus, including those between Jacobaea vulgaris and its relatives. Although Jacobaea erucifolia and J. vulgaris often co-occur and are considered closely related, apart from the few reports of German botanists on the existence of such hybrids, there is no information on research confirming hybridization between them. Morphologically intermediate individuals, found in the sympatric distributions of J. vulgaris and J. erucifolia, were hypothesized to be their hybrids. Two molecular marker systems (nuclear and chloroplast DNA markers) were employed to test this hypothesis and characterize putative hybrids. Nuclear and chloroplast DNA sequencing results and taxon-specific amplified fragment length polymorphism (AFLP) fragment distribution analysis confirmed the hybrid nature of all 25 putative hybrids. The AFLP patterns of most hybrids demonstrated a closer relationship to J. erucifolia, suggesting frequent backcrossing. Moreover, they showed that several individuals previously described as pure were probably also of hybrid origin, backcrosses to J. erucifolia and J. vulgaris. This study provides the first molecular confirmation that natural hybrids between J. vulgaris and J. erucifolia occur in Poland. Hybridization appeared to be bidirectional but asymmetrical with J. vulgaris as the usual maternal parent.

2.
PLoS One ; 14(12): e0226985, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31869386

RESUMO

In this study, possible hybridization between two allopatric species, Cornus controversa and Cornus alternifolia, was explored using molecular and morphological approaches. Scanning electron microscope analyses of the adaxial and the abaxial leaf surfaces yielded a few new not yet described characters typical for the particular species and intermediate for hybrids. With the use of 14 Random Amplified Polymorphic DNA and 5 Amplified Fragment Length Polymorphism primer combinations, 44 fragments species specific to C. controversa and 51 species specific to C. alternifolia were obtained. Most of these bands were also found in putative hybrids. All clustering analyses based on binary data combined from both methods confirmed a separate and intermediate status of the hybrids. Hybrid index estimates for hybrids C1-C5 indicated that all were the first generation of offspring (F1). Chloroplast intergenic spacers (trnF-trnL and psbC-trnS) were used to infer the hybridization direction. Based on the assumption of maternal inheritance of chloroplast DNA, C. controversa seems to be the maternal parent of the hybrid. Internal transcribed spacer sequences of the five hybrids analyzed here indicated higher similarity with the sequences of C. controversa (all shared the majority of its single nucleotide polymorphisms). Sequence analysis of PI-like genes fully confirmed the hybrid origin of C1-C5 hybrids. Our results also showed that two specimens in the C. alternifolia group, A1 and A3, are not free of introgression. They are probably repeated backcrosses toward C. alternifolia. Furthermore, molecular data seem to point not only to unidirectional introgression toward C. controversa (the presence of hybrids) but to bidirectional introgression as well, since the presence of markers specific for C. controversa in the profiles of C. alternifolia specimen A3 was observed.


Assuntos
Cornus/genética , Hibridização Genética , Folhas de Planta/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Cornus/ultraestrutura , DNA de Cloroplastos/genética , Folhas de Planta/ultraestrutura , Técnica de Amplificação ao Acaso de DNA Polimórfico
3.
Cryo Letters ; 36(1): 8-18, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26017175

RESUMO

OBJECTIVE: Examination of effect of vitrification solution with or without foetal calf serum (FCS) on the in vitro and in vivo survival of matured pig oocytes. MATERIALS AND METHODS: Exp. 1: oocytes were exposed to vitrification solutions: VSa (15% DMSO, 15% EG, 0.5 M sucrose dissolved in TCM-199 with FCS) or VSb (VSa without FCS). Exp. 2: oocytes were vitrified in VSa or VSb using OPS. A fraction of vitrified oocytes were transferred to 6 synchronised and inseminated recipients.. RESULTS: Survival rate after exposure and vitrification was the same for VSa and VSb. Transfer of 48 oocytes vitrified in VSb resulted with two pregnancies and 12 live piglets. Molecular analysis results: eight piglets originated from the surrogate mother's oocytes, four piglets from vitrified oocytes.. CONCLUSION: The use of DMSO and EG as cryoprotectants without serum supplementation was advantageous for the in vivo development of vitrified mature porcine oocytes.


Assuntos
Criopreservação/veterinária , Fertilização in vitro/veterinária , Oócitos/citologia , Suínos/fisiologia , Vitrificação , Animais , Animais Recém-Nascidos , Sobrevivência Celular/efeitos dos fármacos , Criopreservação/métodos , Crioprotetores/metabolismo , Feminino , Fertilização in vitro/métodos , Oócitos/efeitos dos fármacos , Oócitos/metabolismo
4.
Environ Monit Assess ; 187(1): 4125, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25384374

RESUMO

Slurry sampling graphite furnace atomic absorption spectrometry technique was applied for the determination of Bi in environmental samples. The study focused on the effect of Zr, Ti, Nb and W carbides, as permanent modifiers, on the Bi signal. Because of its highest thermal and chemical stability and ability to substantially increase Bi signal, NbC was chosen as the most effective modifier. The temperature programme applied for Bi determination was optimized based on the pyrolysis and atomization curves obtained for slurries prepared from certified reference materials (CRMs) of the soil and sediments. To overcome interferences caused by sulfur compounds, Ba(NO3)2 was used as a chemical modifier. Calibration was performed using the aqueous standard solutions. The analysis of the CRMs confirmed the reliability of the proposed analytical method. The characteristic mass for Bi was determined to be 16 pg with the detection limit of 50 ng/g for the optimized procedure at the 5% (w/v) slurry concentration.


Assuntos
Bismuto/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Grafite/química , Bismuto/química , Calibragem , Poluentes Ambientais/química , Limite de Detecção , Reprodutibilidade dos Testes , Solo , Espectrofotometria Atômica/métodos , Temperatura
5.
Arch Immunol Ther Exp (Warsz) ; 62(5): 411-22, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24554032

RESUMO

Hyperacute rejection (HAR) depends on the response of xenoreactive antibodies principally against porcine α-Gal epitope. Methods eliminating HAR include GGTA1 inactivation, regulation of the complement system and modification of the oligosaccharide structure of surface proteins in donor's cells. Transgenic animals designed for the purpose of xenotransplantation with single modification do not display full reduction of the α-Gal epitope level, which means that a accumulation of several modifications in one transgenic individual is needed. The aim of the study was to create a molecular and cytogenetic profile of a double transgenic animal with α1,2-fucosyltransferase and α-galactosidase expression. As a result of interbreeding of an individual with α1,2-fucosyltransferase expression with an individual with α-galactosidase expression 12 living piglets were obtained. PCR revealed the pCMVFUT gene construct was present in four individuals and pGAL-GFPBsd in three, including one with a confirmed integration of both the gene constructs. Fluorescence in situ hybridization confirmed the site of transgene integration, which corresponded to the mapping site of the transgenes which occurred in the parental generations. Karyotype analysis did not show any changes in the structure or the number of chromosomes (2n = 38, XX). As for the results pertaining to the single transgenic individuals, expression analysis demonstrated a high extent of α-Gal epitope level reduction on the surface of cells, whereas human serum cytotoxicity tests revealed the smallest decrease in longevity of cells in the obtained double transgenic individual (4.35 %). The tests suggest that the co-expression of both the transgenes leads to a considerable reduction of the α-Gal antigen level on the surface of cells and a decrease of xenotransplant immunogenicity.


Assuntos
Fibroblastos/fisiologia , Fucosiltransferases/imunologia , Rejeição de Enxerto/prevenção & controle , Transplante Heterólogo , alfa-Galactosidase/imunologia , Animais , Animais Geneticamente Modificados , Citotoxicidade Celular Dependente de Anticorpos/genética , Linhagem Celular , Epitopos de Linfócito B/genética , Fucosiltransferases/genética , Rejeição de Enxerto/etiologia , Humanos , Imunidade Humoral/genética , Soro/imunologia , Suínos , alfa-Galactosidase/genética , Galactosídeo 2-alfa-L-Fucosiltransferase
6.
J Bioinform Comput Biol ; 4(2): 483-501, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16819797

RESUMO

We demonstrate how automated text analysis can be used to support the large-scale analysis of metabolic and regulatory pathways by deriving pathway maps from textual descriptions found in the scientific literature. The main assumption is that correct syntactic analysis combined with domain-specific heuristics provides a good basis for relation extraction. Our method uses an algorithm that searches through the syntactic trees produced by a parser based on a Referent Grammar formalism, identifies relations mentioned in the sentence, and classifies them with respect to their semantic class and epistemic status (facts, counterfactuals, hypotheses). The semantic categories used in the classification are based on the relation set used in KEGG (Kyoto Encyclopedia of Genes and Genomes), so that pathway maps using KEGG notation can be automatically generated. We present the current version of the relation extraction algorithm and an evaluation based on a corpus of abstracts obtained from PubMed. The results indicate that the method is able to combine a reasonable coverage with high accuracy. We found that 61% of all sentences were parsed, and 97% of the parse trees were judged to be correct. The extraction algorithm was tested on a sample of 300 parse trees and was found to produce correct extractions in 90.5% of the cases.


Assuntos
Algoritmos , Inteligência Artificial , Modelos Biológicos , Processamento de Linguagem Natural , Publicações Periódicas como Assunto , Proteoma/metabolismo , Transdução de Sinais/fisiologia , Indexação e Redação de Resumos/métodos , Sistemas de Gerenciamento de Base de Dados , Bases de Dados de Proteínas , Armazenamento e Recuperação da Informação/métodos , Proteoma/classificação , Semântica , Vocabulário Controlado
7.
Breast Cancer Res Treat ; 78(1): 17-27, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12611453

RESUMO

We have prepared conjugates of a membrane disrupting lytic peptide (hecate) and a 15-amino acid segment of the beta-chain of CG and hecate and the decapeptide, luteinizing hormone releasing hormone (LHRH). We have tested the concept that these conjugates will target breast cancer cells expressing LH/CG or LHRH receptors. In previous studies, we were able to destroy prostate cancers in vitro and in vivo with lytic peptide conjugates. Hecate, hecate-betaCG and LHRH-hecate were added to cultures of the human breast cancer cell lines MCF-7 and MDA-MB-435S. Hecate and its conjugates showed concentration dependent toxicity to both cell lines. The lytic peptide alone showed similar EC50 values for both cell lines; however, there was a significant difference between the EC50 values when the conjugates were tested. The hormone dependent MCF-7 cell line was less sensitive to the betaCG conjugate than to the LHRH conjugate; the reverse was found for the hormone independent MDA-MB-435S cells. Removal of steroids decreased the sensitivity of MCF-7 cells to both lytic peptide conjugates and this sensitivity could be restored by adding estradiol. Activation of protein kinase C further increased the sensitivity to the drug. MDA-MB-435S xenografts were established in intact female athymic nude mice, which were treated once a week for 3 weeks with hecate-betaCG via the lateral tail vein. The ability of hecate-betaCG to destroy xenografts of human breast cancer cells (MDA-MB-435S) in nude mice was demonstrated for the first time. We conclude that hecate-betaCG and LHRH-hecate conjugates could serve as useful drugs for the treatment of breast cancer.


Assuntos
Membrana Celular/efeitos dos fármacos , Gonadotropina Coriônica Humana Subunidade beta/farmacologia , Hormônio Liberador de Gonadotropina/farmacologia , Neoplasias Mamárias Experimentais/fisiopatologia , Meliteno/análogos & derivados , Meliteno/farmacologia , Neoplasias Hormônio-Dependentes/fisiopatologia , Sequência de Aminoácidos , Animais , Membrana Celular/patologia , Gonadotropina Coriônica Humana Subunidade beta/análogos & derivados , Feminino , Hormônio Liberador de Gonadotropina/análogos & derivados , Neoplasias Mamárias Experimentais/tratamento farmacológico , Camundongos , Camundongos Nus , Modelos Animais , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Biol Reprod ; 68(5): 1674-81, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12606417

RESUMO

The objective of this study was to determine whether nitric oxide (NO) is produced locally in the bovine corpus luteum (CL) and whether NO mediates prostaglandin F2alpha (PGF2alpha)-induced regression of the bovine CL in vivo. The local production of NO was determined in early I, early II, mid, late, and regressed stages of CL by determining NADPH-d activity and the presence of inducible and endothelial NO synthase immunolabeling. To determine whether inhibition of NO production counteracts the PGF2alpha-induced regression of the CL, saline (10 ml/h; n = 10) or a nonselective NOS inhibitor (Nomega-nitro-l-arginine methyl ester dihydrochloride [L-NAME]; 400 mg/h; n = 9) was infused for 2 h on Day 15 of the estrous cycle into the aorta abdominalis of Holstein/Polish Black and White heifers. After 30 min of infusion, saline or cloprostenol, an analogue of PGF2alpha (aPGF2alpha; 100 microg) was injected into the aorta abdominalis of animals infused with saline or L-NAME. NADPH-diaphorase activity was present in bovine CL, with the highest activity at mid and late luteal stages (P < 0.05). Inducible and endothelial NO synthases were observed with the strongest immunolabeling in the late CL (P < 0.05). Injection of aPGF2alpha increased nitrite/nitrate concentrations (P < 0.01) and inhibited P4 secretion (P < 0.05) in heifers that were infused with saline. Infusion of L-NAME stimulated P4 secretion (P < 0.05) and concomitantly inhibited plasma concentrations of nitrite/nitrate (P < 0.05). Concentrations of P4 in heifers infused with L-NAME and injected with aPGF2alpha were higher (P < 0.05) than in animals injected only with aPGF2alpha. The PGF2alpha analogue shortened the cycle length compared with that of saline (17.5 +/- 0.22 days vs. 21.5 +/- 0.65 days P < 0.05). L-NAME blocked the luteolytic action of the aPGF2alpha (22.6 +/- 1.07 days vs. 17.5 +/- 0.22 days, P < 0.05). These results suggest that NO is produced in the bovine CL. NO inhibits luteal steroidogenesis and it may be one of the components of an autocrine/paracrine luteolytic cascade induced by PGF2alpha.


Assuntos
Dinoprosta/antagonistas & inibidores , Dinoprosta/farmacologia , Inibidores Enzimáticos/farmacologia , Luteólise/efeitos dos fármacos , Óxido Nítrico Sintase/antagonistas & inibidores , Animais , Bovinos , Relação Dose-Resposta a Droga , Ciclo Estral/fisiologia , Feminino , Imuno-Histoquímica , NADPH Desidrogenase/metabolismo , NG-Nitroarginina Metil Éster/farmacologia , Nitratos/sangue , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo I , Óxido Nítrico Sintase Tipo III , Nitritos/sangue , Progesterona/sangue
9.
Gynecol Oncol ; 85(1): 45-52, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11925119

RESUMO

OBJECTIVE: The aim of this study was to determine the in vitro and in vivo effects of the lytic peptide, hecate, alone and conjugated to a 15-amino-acid fragment of the beta-chain of hCG (hecate-beta hCG) on the ovarian carcinoma cell line NIH: OVCAR-3 and determine the expression of luteinizing hormone (LH)/human chorionic gonadotropin (hCG) receptors in cell cultures and tumor tissues. METHODS: For in vitro studies, hecate or hecate-beta hCG was added to cultures of ovarian cancer cells in the presence or absence of estradiol or follicle stimulating hormone. The cytotoxicity of lytic peptides was measured by trypan blue exclusion and lactate dehydrogenase release. For in vivo studies, OVCAR-3 xenografts were established in female athymic nude mice which were then treated once per week for 3 weeks with hecate or hecate-beta hCG via the lateral tail vein. An immunohistochemical method was used to analyze the expression of LH/hCG receptor in tumor and culture cells. RESULTS: In in vitro studies, both hecate-beta hCG and hecate destroyed ovarian cancer cells (NIH: OVCAR-3) in a dose-dependent manner. Removal of steroids from the culture medium reduced the sensitivity of the OVCAR-3 cell line to the hecate-beta hCG in a reversible manner. In in vivo studies, the average tumor volume and tumor burden in lytic peptide treated animals were reduced. In the groups of animals treated by hecate, hecate-beta hCG, and estradiol + hecate-beta hCG, tumor volumes after treatment expressed as a percentage of increase (197.4 +/- 21.72, 199.0 +/- 18.57, and 193.8 +/- 22.94%, respectively) were reduced, compared to control (263.0 +/- 21.72%) animals (P < 0.05). Immunocytochemical studies revealed the expression of LH/hCG receptor protein in the OVCAR-3 cells and tumor tissues. CONCLUSION: Hecate-beta hCG is a putative candidate for treating ovarian cancer.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/farmacologia , Meliteno/análogos & derivados , Meliteno/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Animais , Gonadotropina Coriônica Humana Subunidade beta/administração & dosagem , Gonadotropina Coriônica Humana Subunidade beta/química , Feminino , Humanos , Imuno-Histoquímica , Meliteno/administração & dosagem , Meliteno/química , Camundongos , Camundongos Nus , Neoplasias Ovarianas/metabolismo , Receptores do LH/biossíntese , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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