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1.
J Environ Sci Health B ; 58(10): 617-627, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37671814

RESUMEN

The Ferronikel smelter in Drenas is one of the main industrial areas in the Kosovo and pollution by heavy metals causes serious threat for all living organisms on this area. The objective of this study was to determine the concentration of some heavy metals (Fe, Cu, Mn, Cr, Cd, Ni and Pb) in agricultural soils and in maize plants, and their potential toxic effects on this plant through some sensitive biochemical and molecular markers. Maize seedlings growth in nine soil samples from different locations of this area. The highest concentrations of heavy metals in soils and maize leaves were conducted close to the Ferronikel smelter, and in some locations, the nickel and chromium concertation in soils exceeded 800 mg kg-1. A significant effects of heavy metals induced toxicity resulted in the, build-up aminolevulinic acid and reduced activity of δ-aminolevulinic acid dehydratase, and chlorophyll content in the maize leaves. In general, maize seedlings growth in polluted locations showed an increase in nuclear DNA content and in G2M phase. We concluded that locations close to the smelter are affected by soil heavy metals pollution and these biochemical and molecular analysis would be a powerful ecotoxicological tool in biomonitoring of heavy metal pollution.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Suelo/química , Zea mays , Kosovo , Monitoreo del Ambiente/métodos , Contaminantes del Suelo/análisis , Metales Pesados/toxicidad , Metales Pesados/análisis , Biomarcadores , Daño del ADN , Medición de Riesgo , China
2.
J Environ Sci Health B ; 58(12): 718-725, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37897250

RESUMEN

The aim of this study was to gain a better understanding of how Tulipa luanica adapts to growth in soil with higher concentrations of heavy metals and to assess potential toxic effects using various biomarkers, in comparison to Tulipa kosovarica, a typical serpentine species. For this purpose, we analyzed the concentrations of Al, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, and Zn in the soil, as well as their accumulation in plants and their associated stress effects. The results indicate that, despite the presence of some metals in very high concentrations in the soil (Al, Fe, Mn, and Ni), they are translocated in minimal amounts within plant organs, particularly in T. luanica. Nearly all metals exhibited significantly higher concentrations in T. kosovarica when compared to T. luanica. Based on the analysis of biomarkers, it is apparent that T. luanica shows greater sensitivity to these conditions. This is evident through the decreased activity of δ-aminolevulinic acid dehydratase and levels of δ-aminolevulinic acid, malondialdehyde, and glutathione observed in T. luanica. It appears that T. luanica effectively restricts the absorption of metals in serpentine soils; however, it experiences oxidative stress induced by these metals, setting it apart from the more resilient T. kosovarica.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Tulipa , Suelo , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Metales Pesados/toxicidad , Metales Pesados/análisis , Monitoreo del Ambiente/métodos
3.
Mol Biol Rep ; 49(6): 5659-5668, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35612778

RESUMEN

BACKGROUND: Onobrychis viciifolia Scop. is a short-lived perennial cool-season legume used for forage production. It is a common native species in Asia Minor, especially in Turkey, the districts of the Caucasus, and the Caspian fringes. It can grow well in a broad range of climatic and soil types found in Asia, Europe, and North America. It is a non-bloating crop, making it suitable for use in both hay and pasture. METHODS AND RESULTS: The aim was to assess the diversity of the 83 sainfoin genotypes selected based on their high agronomic performance from a germplasm collection evaluated in the experimental field of Tekirdag Namik Kemal University, Turkey. Ten nuclear simple sequence repeat (nSSR) primers (OVK036, OVK046, OVK094, OVK101, OVK125, OVK161, OVK174, OVM033, OVM061, and OVM125) were used in the study. All nSSR loci were found to be polymorphic and totally 92 alleles were detected. The mean observed number of alleles per locus was calculated as 9.2. Among the genetic diversity parameters, Shannon Index (I = 0.375), unbiased genetic diversity value (uh = 0.243), and mean polymorphic information content (PIC = 0.240) were calculated. The genetic distance value varied between 0.43 and 0.95. Based on the dendrogram built by the UPGMA clustering method using genetic distance values, it was observed that the studied sainfoin genotypes were divided into two main clusters, whereas the STRUCTURE analysis results had high support for three clusters. CONCLUSIONS: The results obtained from this study provide important information on the genetic structures of the studied sainfoin genotypes and their genetic relationship. Therefore acquired genetic data will be useful in designing more efficient polycross nurseries, allowing open pollination of best performing and genetically diverse genotypes in the isolated conditions, which will increase genetic gain in sainfoin breeding programs.


Asunto(s)
Fabaceae , Fitomejoramiento , Biomarcadores , Cartilla de ADN , Fabaceae/genética , Variación Genética , Repeticiones de Microsatélite
4.
Int J Mol Sci ; 23(19)2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-36232345

RESUMEN

The evolution of chromosome number and ribosomal DNA (rDNA) loci number and localisation were studied in Onobrychis Mill. Diploid and tetraploid species, as well as two basic chromosome numbers, x = 7 and x = 8, were observed among analysed taxa. The chromosomal distribution of rDNA loci was presented here for the first time using fluorescence in situ hybridisation (FISH) with 5S and 35S rDNA probes. Onobrychis species showed a high polymorphism in the number and localisation of rDNA loci among diploids, whereas the rDNA loci pattern was very similar in polyploids. Phylogenetic relationships among the species, inferred from nrITS sequences, were used as a framework to reconstruct the patterns of basic chromosome number and rDNA loci evolution. Analysis of the evolution of the basic chromosome numbers allowed the inference of x = 8 as the ancestral number and the descending dysploidy and polyploidisation as the major mechanisms of the chromosome number evolution. Analyses of chromosomal patterns of rRNA gene loci in a phylogenetic context resulted in the reconstruction of one locus of 5S rDNA and one locus of 35S rDNA in the interstitial chromosomal position as the ancestral state in this genus.


Asunto(s)
Cromosomas de las Plantas , Fabaceae , Cromosomas de las Plantas/genética , ADN de Plantas/genética , ADN Ribosómico/genética , Evolución Molecular , Fabaceae/genética , Filogenia
5.
Plant J ; 103(5): 1810-1825, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32506573

RESUMEN

Nucleolar dominance (ND) consists of the reversible silencing of 35S/45S rDNA loci inherited from one of the ancestors of an allopolyploid. The molecular mechanisms by which one ancestral rDNA set is selected for silencing remain unclear. We applied a combination of molecular (Southern blot hybridization and reverse-transcription cleaved amplified polymorphic sequence analysis), genomic (analysis of variants) and cytogenetic (fluorescence in situ hybridization) approaches to study the structure, expression and epigenetic landscape of 35S rDNA in an allotetraploid grass that exhibits ND, Brachypodium hybridum (genome composition DDSS), and its putative progenitors, Brachypodium distachyon (DD) and Brachypodium stacei (SS). In progenitor genomes, B. stacei showed a higher intragenomic heterogeneity of rDNA compared with B. distachyon. In all studied accessions of B. hybridum, there was a reduction in the copy number of S homoeologues, which was accompanied by their inactive transcriptional status. The involvement of DNA methylation in CG and CHG contexts in the silencing of the S-genome rDNA loci was revealed. In the B. hybridum allotetraploid, ND is stabilized towards the D-genome units, irrespective of the polyphyletic origin of the species, and does not seem to be influenced by homoeologous 35S rDNA ratios and developmental stage.


Asunto(s)
Brachypodium/genética , Genes de Plantas/genética , Genes de ARNr/genética , Tetraploidía , Southern Blotting , Brachypodium/metabolismo , Cromosomas de las Plantas/genética , Variaciones en el Número de Copia de ADN/genética , Metilación de ADN/genética , Evolución Molecular , Sitios Genéticos/genética , Genoma de Planta/genética , Polimorfismo Genético/genética
6.
Mol Biol Rep ; 47(6): 4455-4463, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32447499

RESUMEN

This study was initiated to reveal genetic relationship of 25 tef (Eragrostis tef (Zucc.) accessions by using 10 SSR markers and to determine DNA content variation by using flow cytometer analysis. Ten markers produced a total of 18 alleles and 11 of those were polymorphic. The mean polymorphism rate was 66.6%. The highest polymorphism information content value was obtained from marker CNLTs370 with 0.69 while markers CNTLs11 and CNTLs133 produced monomorphic bands only. UPGMA analysis divided 25 tef genotypes into three main clades. The accessions PI193511 and PI195934 were distinctly separated from the others. No ploidy differences were determined among the 25 tef accessions. 2C mean nuclear DNA content ranged from 1.406 pg to 1.510 with mean of 1.460 pg. The results of this study indicated that SSR markers successfully determined genetic relationship of 25 tef accession although they had a low rate of polymorphism. This study also revealed that available tef related SSR markers should be optimized before use and their efficiency may vary based on tef genotypes or accessions used.


Asunto(s)
Eragrostis/genética , Alelos , ADN/análisis , ADN/genética , Bases de Datos Genéticas , Citometría de Flujo/métodos , Perfilación de la Expresión Génica , Genes de Plantas/genética , Marcadores Genéticos/genética , Variación Genética/genética , Genotipo , Repeticiones de Microsatélite/genética , Polimorfismo Genético/genética , Transcriptoma/genética
7.
Int J Mol Sci ; 21(18)2020 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-32933168

RESUMEN

Brachypodium distachyon (Brachypodium) is a non-domesticated model grass species that can be used to test if variation in genetic sequence or methylation are linked to environmental differences. To assess this, we collected seeds from 12 sites within five climatically distinct regions of Turkey. Seeds from each region were grown under standardized growth conditions in the UK to preserve methylated sequence variation. At six weeks following germination, leaves were sampled and assessed for genomic and DNA methylation variation. In a follow-up experiment, phenomic approaches were used to describe plant growth and drought responses. Genome sequencing and population structure analysis suggested three ancestral clusters across the Mediterranean, two of which were geographically separated in Turkey into coastal and central subpopulations. Phenotypic analyses showed that the coastal subpopulation tended to exhibit relatively delayed flowering and the central, increased drought tolerance as indicated by reduced yellowing. Genome-wide methylation analyses in GpC, CHG and CHH contexts also showed variation which aligned with the separation into coastal and central subpopulations. The climate niche modelling of both subpopulations showed a significant influence from the "Precipitation in the Driest Quarter" on the central subpopulation and "Temperature of the Coldest Month" on the coastal subpopulation. Our work demonstrates genetic diversity and variation in DNA methylation in Turkish accessions of Brachypodium that may be associated with climate variables and the molecular basis of which will feature in ongoing analyses.


Asunto(s)
Brachypodium/genética , Metilación de ADN/genética , Variación Genética/genética , Clima , Sequías , Genoma de Planta/genética , Hojas de la Planta/genética , Semillas/genética , Estrés Fisiológico/genética , Turquía
8.
Physiol Mol Biol Plants ; 24(6): 1117-1126, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30425428

RESUMEN

The purpose of this study was to determine the concentration of some metals (Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn, Ca and Mg) in soil of serpentine and limestone sites, their bioaccumulation and impact on some biochemical parameters in T. luanica, T. kosovarica and T. albanica plants. T. kosovarica and T. albanica grows in serpentine soil, while T. luanica grow in limestone soil. The research showed that concentrations of Cd, Co, Cr, Fe, Mn and Ni were significantly higher at serpentine soil sites in comparison with limestone sites, while concentrations of Pb, Cd, Co and Cr in bulbs, leaves and seeds were under the limit of detection. The concentration of Ni in plant samples of T. kosovarica was significantly higher in comparison with its concentration in T. albanica, but it was under the limit of detection in T. luanica. Moreover, concentrations of Al and Fe in leaves of T. kosovarica and T. albanica were higher in comparison with T. luanica. The concentration of Mg was significantly higher in T. kosovarica and T. albanica than in T. luanica. The δ-aminolevulinic acid dehydratase activity, malondialdehyde and glutathione contents in leaves of T. luanica were higher in comparison with T. kosovarica and T. albanica. In addition, the amounts of total chlorophyll and δ-aminolevulinic acid (ALA) in leaves of T. albanica were higher in comparison with T. kosovarica and T. luanica. Our findings show that target organs of metal accumulation in three Tulip species appears to be leaves > seeds > bulbs, while the biochemical parameters show that limestone sites represent a less stressful habitat for growing these plant species in comparison with serpentine sites.

9.
Plant J ; 79(3): 361-74, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24888695

RESUMEN

Brachypodium distachyon is small annual grass that has been adopted as a model for the grasses. Its small genome, high-quality reference genome, large germplasm collection, and selfing nature make it an excellent subject for studies of natural variation. We sequenced six divergent lines to identify a comprehensive set of polymorphisms and analyze their distribution and concordance with gene expression. Multiple methods and controls were utilized to identify polymorphisms and validate their quality. mRNA-Seq experiments under control and simulated drought-stress conditions, identified 300 genes with a genotype-dependent treatment response. We showed that large-scale sequence variants had extremely high concordance with altered expression of hundreds of genes, including many with genotype-dependent treatment responses. We generated a deep mRNA-Seq dataset for the most divergent line and created a de novo transcriptome assembly. This led to the discovery of >2400 previously unannotated transcripts and hundreds of genes not present in the reference genome. We built a public database for visualization and investigation of sequence variants among these widely used inbred lines.


Asunto(s)
Brachypodium/genética , Variación Genética , Genoma de Planta/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Sequías , Transcriptoma/genética
10.
BMC Genomics ; 15: 801, 2014 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-25236859

RESUMEN

BACKGROUND: The local environment plays a major role in the spatial distribution of plant populations. Natural plant populations have an extremely poor displacing capacity, so their continued survival in a given environment depends on how well they adapt to local pedoclimatic conditions. Genomic tools can be used to identify adaptive traits at a DNA level and to further our understanding of evolutionary processes. Here we report the use of genotyping-by-sequencing on local groups of the sequenced monocot model species Brachypodium distachyon. Exploiting population genetics, landscape genomics and genome wide association studies, we evaluate B. distachyon role as a natural probe for identifying genomic loci involved in environmental adaptation. RESULTS: Brachypodium distachyon individuals were sampled in nine locations with different ecologies and characterized with 16,697 SNPs. Variations in sequencing depth showed consistent patterns at 8,072 genomic bins, which were significantly enriched in transposable elements. We investigated the structuration and diversity of this collection, and exploited climatic data to identify loci with adaptive significance through i) two different approaches for genome wide association analyses considering climatic variation, ii) an outlier loci approach, and iii) a canonical correlation analysis on differentially sequenced bins. A linkage disequilibrium-corrected Bonferroni method was applied to filter associations. The two association methods jointly identified a set of 15 genes significantly related to environmental adaptation. The outlier loci approach revealed that 5.7% of the loci analysed were under selection. The canonical correlation analysis showed that the distribution of some differentially sequenced regions was associated to environmental variation. CONCLUSIONS: We show that the multi-faceted approach used here targeted different components of B. distachyon adaptive variation, and may lead to the discovery of genes related to environmental adaptation in natural populations. Its application to a model species with a fully sequenced genome is a modular strategy that enables the stratification of biological material and thus improves our knowledge of the functional loci determining adaptation in near-crop species. When coupled with population genetics and measures of genomic structuration, methods coming from genome wide association studies may lead to the exploitation of model species as natural probes to identify loci related to environmental adaptation.


Asunto(s)
Adaptación Fisiológica/genética , Brachypodium/genética , Brachypodium/fisiología , Ambiente , Genómica , Técnicas de Genotipaje , Análisis de Secuencia , Genes de Plantas/genética , Sitios Genéticos/genética , Filogenia , Polimorfismo de Nucleótido Simple
11.
Theor Appl Genet ; 123(1): 119-29, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21465186

RESUMEN

Orchardgrass, or cocksfoot [Dactylis glomerata (L.)], has been naturalized on nearly every continent and is a commonly used species for forage and hay production. All major cultivated varieties of orchardgrass are autotetraploid, and few tools or information are available for functional and comparative genetic analyses and improvement of the species. To improve the genetic resources for orchardgrass, we have developed an EST library and SSR markers from salt, drought, and cold stressed tissues. The ESTs were bi-directionally sequenced from clones and combined into 17,373 unigenes. Unigenes were annotated based on putative orthology to genes from rice, Triticeae grasses, other Poaceae, Arabidopsis, and the non-redundant database of the NCBI. Of 1,162 SSR markers developed, approximately 80% showed amplification products across a set of orchardgrass germplasm, and 40% across related Festuca and Lolium species. When orchardgrass subspecies were genotyped using 33 SSR markers their within-accession similarity values ranged from 0.44 to 0.71, with Mediterranean accessions having a higher similarity. The total number of genotyped bands was greater for tetraploid accessions compared to diploid accessions. Clustering analysis indicated grouping of Mediterranean subspecies and central Asian subspecies, while the D. glomerata ssp. aschersoniana was closest related to three cultivated varieties.


Asunto(s)
Dactylis/genética , Etiquetas de Secuencia Expresada , Técnicas de Transferencia de Gen , Marcadores Genéticos , Anotación de Secuencia Molecular , Secuencia de Aminoácidos , Mapeo Cromosómico , Análisis por Conglomerados , Festuca/genética , Biblioteca de Genes , Genes de Plantas , Genotipo , Lolium/genética , Polimorfismo Genético , Tetraploidía
12.
Cells ; 10(3)2021 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-33808796

RESUMEN

Brachypodium distachyon (Brachypodium) is a non-domesticated model grass that has been used to assess population level genomic variation. We have previously established a collection of 55 Brachypodium accessions that were sampled to reflect five different climatic regions of Turkey; designated 1a, 1c, 2, 3 and 4. Genomic and methylomic variation differentiated the collection into two subpopulations designated as coastal and central (respectively from regions 1a, 1c and the other from 2, 3 and 4) which were linked to environmental variables such as relative precipitation. Here, we assessed how far genomic variation would be reflected in the metabolomes and if this could be linked to an adaptive trait. Metabolites were extracted from eight-week-old seedlings from each accession and assessed using flow infusion high-resolution mass spectrometry (FIE-HRMS). Principal Component Analysis (PCA) of the derived metabolomes differentiated between samples from coastal and central subpopulations. The major sources of variation between seedling from the coastal and central subpopulations were identified. The central subpopulation was typified by significant increases in alanine, aspartate and glutamate metabolism and the tricarboxylic acid (TCA) cycle. Coastal subpopulation exhibited elevated levels of the auxin, indolacetic acid and rhamnose. The metabolomes of the seedling were also determined following the imposition of drought stress for seven days. The central subpopulation exhibited a metabolomic shift in response to drought, but no significant changes were seen in the coastal one. The drought responses in the central subpopulation were typified by changes in amino acids, increasing the glutamine that could be functioning as a stress signal. There were also changes in sugars that were likely to be an osmotic counter to drought, and changes in bioenergetic metabolism. These data indicate that genomic variation in our Turkish Brachypodium collection is largely reflected as distinctive metabolomes ("metabolotypes") through which drought tolerance might be mediated.


Asunto(s)
Brachypodium/metabolismo , Ácidos Indolacéticos/farmacología , Metaboloma/efectos de los fármacos , Hojas de la Planta/metabolismo , Estrés Fisiológico/fisiología , Brachypodium/genética , Variación Genética/efectos de los fármacos , Metabolómica/métodos , Fenotipo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/fisiología , Plantones/metabolismo , Estrés Fisiológico/genética
13.
BMC Plant Biol ; 9: 88, 2009 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-19594938

RESUMEN

BACKGROUND: Brachypodium distachyon (Brachypodium) is rapidly emerging as a powerful model system to facilitate research aimed at improving grass crops for grain, forage and energy production. To characterize the natural diversity of Brachypodium and provide a valuable new tool to the growing list of resources available to Brachypodium researchers, we created and characterized a large, diverse collection of inbred lines. RESULTS: We developed 84 inbred lines from eight locations in Turkey. To enable genotypic characterization of this collection, we created 398 SSR markers from BAC end and EST sequences. An analysis of 187 diploid lines from 56 locations with 43 SSR markers showed considerable genotypic diversity. There was some correlation between SSR genotypes and broad geographic regions, but there was also a high level of genotypic diversity at individual locations. Phenotypic analysis of this new germplasm resource revealed considerable variation in flowering time, seed size, and plant architecture. The inbreeding nature of Brachypodium was confirmed by an extremely high level of homozygosity in wild plants and a lack of cross-pollination under laboratory conditions. CONCLUSION: Taken together, the inbreeding nature and genotypic diversity observed at individual locations suggest a significant amount of long-distance seed dispersal. The resources developed in this study are freely available to the research community and will facilitate experimental applications based on natural diversity.


Asunto(s)
Genética de Población/métodos , Repeticiones de Minisatélite , Poaceae/genética , Polimorfismo Genético , ADN de Plantas/genética , Etiquetas de Secuencia Expresada , Genes de Plantas , Marcadores Genéticos , Genoma de Planta , Genómica , Genotipo , Geografía , Endogamia , Fenotipo , Filogenia , Plantas Modificadas Genéticamente/genética , Polen/genética , Análisis de Secuencia de ADN , Turquía
14.
Theor Appl Genet ; 118(7): 1309-19, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19229513

RESUMEN

Developing a better understanding of associations among ploidy level, geographic distribution, and genetic diversity of Cynodon accessions could be beneficial to bermudagrass breeding programs, and would enhance our understanding of the evolutionary biology of this warm season grass species. This study was initiated to: (1) determine ploidy analysis of Cynodon accessions collected from Turkey, (2) investigate associations between ploidy level and diversity, (3) determine whether geographic and ploidy distribution are related to nuclear genome variation, and (4) correlate among four nuclear molecular marker systems for Cynodon accessions' genetic analyses. One hundred and eighty-two Cynodon accessions collected in Turkey from an area south of the Taurus Mountains along the Mediterranean cost and ten known genotypes were genotyped using sequence related amplified polymorphism (SRAP), peroxidase gene polymorphism (POGP), inter-simple sequence repeat (ISSR), and random amplified polymorphic DNA (RAPD). The diploids, triploids, tetraploids, pentaploids, and hexaploids revealed by flow cytometry had a linear present band frequency of 0.36, 0.47, 0.49, 0.52, and 0.54, respectively. Regression analysis explained that quadratic relationship between ploidy level and band frequency was the most explanatory (r = 0.62, P < 0.001). The AMOVA results indicated that 91 and 94% of the total variation resided within ploidy level and provinces, respectively. The UPGMA analysis suggested that commercial bermudagrass cultivars only one-third of the available genetic variation. SRAP, POGP, ISSR, and RAPD markers differed in detecting relationships among the bermudagrass genotypes and rare alleles, suggesting more efficiency of combinatory analysis of molecular marker systems. Elucidating Cynodon accessions' genetic structure can aid to enhance breeding programs and broaden genetic base of commercial cultivars.


Asunto(s)
Cynodon/genética , Marcadores Genéticos , Variación Genética , Poliploidía , Evolución Biológica , Cynodon/clasificación , ADN de Plantas/análisis , ADN de Plantas/genética , Genética de Población , Región Mediterránea , Filogenia , Polimorfismo Genético , Turquía
15.
Neurol Res ; 31(7): 714-20, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19036178

RESUMEN

OBJECTIVES: Our aim was to investigate whether neutralization of rat interleukin 6 (IL-6) bioactivity attenuates inducible nitric oxide synthase (iNOS) up-regulation and ameliorates cerebral ischemic damage in a model of focal central nervous system (CNS) ischemia. METHODS: Seventy rats were randomly allocated to groups: Group I (n=10) consisted of normal controls; Group II (n=20) underwent surgical exposure of the middle cerebral artery but no cauterization; the remaining 40 rats were subjected to middle cerebral artery occlusion. Immediately after occlusion, each of these 40 rats was randomly assigned to either the occlusion-only group (Group III, n=20) or the occlusion plus IL-6 antibody treatment group (Group IV, n=20). Half of the rats from each of Groups II, III and IV were eternized at 24 hours and the other half at 72 hours. The samples were used for iNOS immunohistochemistry and structural analysis. RESULTS: A single dose of the antibody had no effect on structural changes and iNOS at 24 hours after occlusion. However, administering three doses of the antibody resulted in markedly decreased quantitative and qualitative levels of iNOS-positive stained cells and milder subcellular damage compared with the findings in the occlusion-only group at 72 hours after occlusion. DISCUSSION: Our findings prove that IL-6 bioactivity is one of the pathological events that trigger the induction of iNOS in the process of CNS ischemic injury. It appears that there may be therapeutic value in neutralization of IL-6 bioactivity to attenuate iNOS up-regulation and ameliorate cerebral ischemic damage in long-term recovery.


Asunto(s)
Anticuerpos/farmacología , Encéfalo/metabolismo , Encéfalo/patología , Infarto de la Arteria Cerebral Media/fisiopatología , Interleucina-6/inmunología , Óxido Nítrico Sintasa de Tipo II/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Animales , Encéfalo/efectos de los fármacos , Encéfalo/enzimología , Encéfalo/ultraestructura , Modelos Animales de Enfermedad , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Infarto de la Arteria Cerebral Media/enzimología , Infarto de la Arteria Cerebral Media/patología , Masculino , Microscopía Electrónica de Transmisión , Distribución Aleatoria , Ratas , Ratas Wistar , Estadísticas no Paramétricas
16.
Skull Base ; 17(3): 157-71, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17973029

RESUMEN

We reviewed the clinical, radiological, surgical, and histopathological features of patients with meningiomas to identify factors that can predict tumor recurrence after "microscopic total removal," to improve preoperative surgical planning, and to help determine the need for close radiological observation at shorter intervals or the need for radiotherapy as an adjuvant treatment in the early postoperative period. Clinical data, magnetic resonance imaging studies, angiographic data, operative reports, and histopathological findings were examined retrospectively in 137 patients with a meningioma treated microsurgically and with no evidence of residual tumor on postoperative MR images. Based on univariate analysis, tumor size, a mushroom shape, proximity to major sinuses, edema, osteolysis, cortical penetration, signal intensity on T2-weighted MRIs, pial-cortical arterial supply, presence of a brain-tumor interface in surgery, Simpson's criteria, and histopathological classification were significant predictors for recurrence. However, age, gender, location of tumor, dural tail, calcification, signal intensity on T1-weighted images, and histopathologic subtypes in the benign group were not significant predictors. By Cox regression analysis the most important variables related to the time to recurrence were mushroom shape, osteolysis, dural tail, and proximity to major sinuses. Aggressive surgical therapy with wider dural removal should be considered in the presence of the preoperative predictors of a recurrence. Close radiological observation at shorter intervals or radiotherapy should be considered as adjuvant therapy in high-risk patients based on surgical findings predicting recurrence related to the brain-tumor interface, Simpson's criteria, and histopathological findings in the early postoperative period.

17.
Neurol Res ; 27(1): 53-6, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15829159

RESUMEN

OBJECTIVE: Congenital intracranial tumors are very rare and only account for 0.5-1.5% of all childhood brain tumors. The most common type of these tumors present at birth is teratomas, which represent 0.5% of all intracranial tumors. Most teratomas are midline tumors located predominantly in the sellar and pineal regions. In this study, we report a neonatal intracranial immature teratoma at the lateral ventricle because of its rare location. CASE REPORT: A 3-day-old female neonate presented with a history of irritability, vomiting, and recurrent generalized clonic seizures since birth. A head computed tomographic scan and magnetic resonance imaging disclosed a large tumor filling the right lateral ventricle and extending into the ipsilateral posterior fossa. With right parieto-occipital craniotomy, large grayish-white lobulated vascular mass was encountered and total removal of tumor was performed. Histological examination revealed the diagnosis of immature teratoma. CONCLUSION: The prognosis of congenital intracranial immature teratoma is usually poor because the lesions are extensive when they are identified. Prenatal ultrasonography is necessary for the prenatal diagnosis. Fetal magnetic resonance imaging should be made for the evaluation of intracranial tumor. If the tumor is detected before the 24 week of gestation, termination of the pregnancy should be considered.


Asunto(s)
Neoplasias del Ventrículo Cerebral/congénito , Ventrículos Laterales/patología , Teratoma/congénito , Neoplasias del Ventrículo Cerebral/patología , Preescolar , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Literatura de Revisión como Asunto , Teratoma/patología , Tomografía Computarizada por Rayos X/métodos
18.
Surg Neurol ; 63(2): 107-12; discussion 112-3, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15680644

RESUMEN

BACKGROUND: This prospective study aimed to determine the spectrum and the main risk factors of surgical site infection (SSI) after neurosurgical procedures in our clinic. METHODS: Consecutive patients undergoing neurosurgery between November 1, 2001, and November 1, 2002, were recruited for the study. All patients were followed for a minimum of 2 weeks postoperatively and all SSIs were recorded. The complete medical records of each case were reviewed, and data on 14 possible risk factors were extracted. Statistical analyses were performed to identify the risk factors for SSIs. RESULTS: A total of 31 postoperative SSIs were identified among 503 cases included in the study, with a resulting overall infection rate of 6.2%. The risk of SSI was increased by age (odds ratio [OR], 1.1; 95% confidence interval [CI], 1.0-1.1; P = .039), operation type such as "shunt operations" (OR, 670.4; 95% CI, 2.6-171123.1; P = .021), presence of foreign body (OR, 141.0; 95% CI, 2.5-7925.9; P = .016), presence of diabetes mellitus (OR, 24.3; 95% CI, 2.1-284.9; P = .011), and intracranial pressure monitoring (OR, 4878.9; 95% CI, 23.8-1001229; P = .002). The predominantly isolated microorganisms in patients with SSIs were Staphylococcus aureus (22 [71.0%]), Acinetobacter baumanii (5 [16.1%]), and Staphylococcus epidermidis (4 [12.9%]). CONCLUSIONS: SSIs remain an important problem in neurosurgery. Identification of the risk factors for SSI will help physicians to improve patient care and may decrease mortality, morbidity, and health care costs of neurosurgery patients.


Asunto(s)
Profilaxis Antibiótica , Procedimientos Neuroquirúrgicos , Infección de la Herida Quirúrgica/epidemiología , Adulto , Factores de Edad , Femenino , Humanos , Modelos Logísticos , Masculino , Procedimientos Neuroquirúrgicos/métodos , Procedimientos Neuroquirúrgicos/estadística & datos numéricos , Estudios Prospectivos , Factores de Riesgo , Turquía/epidemiología
19.
Neurosurgery ; 50(5): 1015-24; discussion 1024-5, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11950404

RESUMEN

OBJECTIVE: We conducted a retrospective study to investigate the prognosis, possible prognostic factors, and long-term natural history of subarachnoid hemorrhage of unexplained cause. METHODS: This report contains a retrospective analysis of data for 84 patients with subarachnoid hemorrhage of unknown cause who were monitored for 1 month to 9.5 years, with an average follow-up period of 5.6 years. We evaluated the associations between computed tomographic (CT) scan features, clinical grade, loss of consciousness during hemorrhage, ventricular ratio, angiographic spasm, complications (such as death resulting from ischemia, early rebleeding, late rebleeding, epilepsy, hydrocephalus, and fixed ischemic deficits), and outcomes, using a nonparametric, two-sample, Kolmogorov-Smirnov test. The chi2 test was used to test the independence of two categorical variables. RESULTS: CT class exhibited a significant association with clinical grade (gamma = 0.865, P = 0.006), loss of consciousness during hemorrhage (gamma = 0.69, P = 0.001), and ventricular ratio (gamma = 0.8175, P = 0.01) but a nonsignificant association with angiographic vasospasm (gamma = 0.21, P = 0.2). Death resulting from ischemic complications and fixed ischemic deficits were strongly associated with clinical grade (P = 0.003 and P = 0.008, respectively) but weakly associated with CT class (P = 0.06 and P = 0.084, respectively). Angiographic vasospasm was strongly associated only with fixed ischemic deficits among complications (P = 0.001). Clinical outcome was strongly positively associated with CT class (gamma = 0.685, P = 0.001), clinical grade (gamma = 0.81, P = 0.001), and ventricular ratio (gamma = 0.57, P = 0.002) but weakly positively associated with loss of consciousness during hemorrhage (gamma = 0.459, P = 0.0487) and angiographic vasospasm (gamma = 0.48, P = 0.04). CONCLUSION: Our study confirms earlier studies reporting a good prognosis for survival, but it does not confirm the earlier statements regarding low morbidity rates. Although clinical grade and the presence and amount of subarachnoid blood on CT scans are the major prognostic factors related to the incidence of ischemic complications, clinical grade and CT class are also the main parameters, with ventricular ratio, indicating clinical outcomes for patients with subarachnoid hemorrhage of unknown cause.


Asunto(s)
Hemorragia Subaracnoidea/etiología , Hemorragia Subaracnoidea/fisiopatología , Adulto , Isquemia Encefálica/epidemiología , Isquemia Encefálica/etiología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/diagnóstico por imagen , Análisis de Supervivencia , Tomografía Computarizada por Rayos X , Vasoespasmo Intracraneal/diagnóstico por imagen , Vasoespasmo Intracraneal/etiología
20.
Neurol Res ; 24(3): 286-90, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11958423

RESUMEN

The purpose of this study was to investigate the relationship among ultrastructural angiogenic features, adenosine-5'-triphosphatase (ATP-ase) activities and superoxide dismutase (SOD) concentration in the microvasculature of intracranial meningiomas and glial tumors. We examined 20 tumor materials from 20 adult patients with intracranial meningioma or glial tumor who underwent selective surgery, dividing them into two groups based on the type of the tumors. Group I consisted of 10 meningioma-materials, and Group II of 10 glial tumor-materials. Na+-K+, Mg+2 and Ca+2 ATP-ase activities in Group I were significantly higher than those in Group II (p < 0.01). The SOD activity in Group I was significantly lower than that in Group II (p < 0.01). According to electron microscopic findings, vascular endothelial proliferation and ultrastructural cytoplasmic changes in the glial tumors were more prominent than those in the meningiomas. Our results show that there is a meaningful correlation among an increased endothelial proliferation, a decreased ATP-ase level and an increased SOD activity in the meningiomas and glial tumors.


Asunto(s)
ATPasa de Ca(2+) y Mg(2+)/metabolismo , ATPasas Transportadoras de Calcio/metabolismo , Glioma/irrigación sanguínea , Glioma/enzimología , Meningioma/irrigación sanguínea , Meningioma/enzimología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Superóxido Dismutasa/metabolismo , Adulto , Glioma/patología , Glioma/ultraestructura , Humanos , Meningioma/patología , Meningioma/ultraestructura , Microcirculación/enzimología , Microcirculación/ultraestructura , Microscopía Electrónica , Neovascularización Patológica/enzimología , Neovascularización Patológica/patología , Estadísticas no Paramétricas
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