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1.
Rhinology ; 62(3): 330-341, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38189480

RESUMO

BACKGROUND: In this study, we identified key discrete clinical and technical factors that may correlate with primary reconstructive success in endoscopic skull base surgery (ESBS). METHODS: ESBS cases with intraoperative cerebrospinal fluid (CSF) leaks at four tertiary academic rhinology programs were retrospectively reviewed. Logistic regression identified factors associated with surgical outcomes by defect subsite (anterior cranial fossa [ACF], suprasellar [SS], purely sellar, posterior cranial fossa [PCF]). RESULTS: Of 706 patients (50.4% female), 61.9% had pituitary adenomas, 73.4% had sellar or SS defects, and 20.5% had high-flow intraoperative CSF leaks. The postoperative CSF leak rate was 7.8%. Larger defect size predicted ACF postoperative leaks; use of rigid reconstruction and older age protected against sellar postoperative leaks; and use of dural sealants compared to fibrin glue protected against PCF postoperative leaks. SS postoperative leaks occurred less frequently with the use of dural onlay. Body-mass index, intraoperative CSF leak flow rate, and the use of lumbar drain were not significantly associated with postoperative CSF leak. Meningitis was associated with larger tumors in ACF defects, nondissolvable nasal packing in SS defects, and high-flow intraoperative leaks in PCF defects. Sinus infections were more common in sellar defects with synthetic grafts and nondissolvable nasal packing. CONCLUSIONS: Depending on defect subsite, reconstructive success following ESBS may be influenced by factors, such as age, defect size, and the use of rigid reconstruction, dural onlay, and tissue sealants.


Assuntos
Vazamento de Líquido Cefalorraquidiano , Endoscopia , Procedimentos de Cirurgia Plástica , Base do Crânio , Humanos , Feminino , Masculino , Base do Crânio/cirurgia , Vazamento de Líquido Cefalorraquidiano/etiologia , Vazamento de Líquido Cefalorraquidiano/prevenção & controle , Vazamento de Líquido Cefalorraquidiano/epidemiologia , Estudos Retrospectivos , Pessoa de Meia-Idade , Endoscopia/métodos , Procedimentos de Cirurgia Plástica/métodos , Adulto , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , Idoso , Neoplasias Hipofisárias/cirurgia , Neoplasias da Base do Crânio/cirurgia , Rinorreia de Líquido Cefalorraquidiano/prevenção & controle , Rinorreia de Líquido Cefalorraquidiano/cirurgia , Rinorreia de Líquido Cefalorraquidiano/etiologia
2.
Mol Biol (Mosk) ; 43(5): 818-27, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19899629

RESUMO

The structure of junction between inverted repeat (IR) and small single copy (SSC) regions of chloroplast genome in the representatives of non-core Caryophyllales is investigated in this work. It was found that for two families - Polygonaceae and Plumbaginaceae - the extension of inverted region is characteristic. This extension is due to the duplication the part of ycf1 gene that is partly located in the small single copy region in plants with typical structure of IR/SSC junctions. Comparison of the position of IR/SSC junctions in different species of Polygonaceae has shown that their exact position is not correlated with the affinity of these species inferred from molecular and morphological data. Possible mechanisms leading to the change in position of IR/SSC junctions observed in this work are discussed.


Assuntos
Caryophyllaceae/genética , Cloroplastos/genética , Evolução Molecular , Genoma de Cloroplastos/fisiologia , Sequências Repetidas Invertidas/genética
3.
Genetika ; 37(9): 1274-80, 2001 Sep.
Artigo em Russo | MEDLINE | ID: mdl-11642131

RESUMO

Nucleotide sequences of a chloroplast rDNA region including 8 bp from the 3' end of 23S rDNA-ITS2-4.5S rDNA-ITS3-5S rDNA-ITS4 (approximately 800 bp) were determined in 25 species of Lycopodiaceae and two species of the genus Isoetes. The rate of molecular evolution of spacers significantly varied in different Lycopsida taxa. A phylogenetic analysis by the neighbor-joining (NJ) method revealed that the family Lycopodiaceae is monophyletic. The topology of phylogenetic trees suggests the isolation of four or probably five genera in family Lycopodiaceae. For these genera, synapomorphic indels were detected. The obtained data were compared with the results of phylogenetic analysis of Lycopsida with regard to other sequences. The relationships of taxa within the family Lycopodiaceae is discussed.


Assuntos
Cloroplastos/genética , Evolução Molecular , Genes de Plantas , Lycopodiaceae/genética , RNA de Plantas/genética , RNA Ribossômico/genética , Filogenia
7.
FEBS Lett ; 422(1): 47-51, 1998 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-9475167

RESUMO

We determined the sequence of the region of the chloroplast DNA inverted repeat spanning from the 3'-terminus of the 23S rRNA gene to the 5'-terminus of the tRNA[Arg](ACG) gene (about 700 bp) from 25 bryophytes and from the charophycean alga Chara australis. Phylogenetic analysis of these sequences using the neighbor-joining method suggests an early dichotomy of bryophytes and their paraphyly relative to the tracheophyte lineage. A monophyly of liverworts (Marchantiidae plus Jungermanniidae), a deep divergence of Metzgeriales among Jungermanniidae and a close affinity of the two subclasses of mosses, Sphagnidae and Andreaeidae, are evident. The branching pattern observed is consistent with the phylogenetic distribution of several prominent indels observed in the alignment.


Assuntos
Bryopsida/genética , DNA Ribossômico/genética , Eucariotos/genética , Sequência de Bases , Cloroplastos/genética , Bases de Dados como Assunto , Evolução Molecular , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 23S/genética , Alinhamento de Sequência , Análise de Sequência de DNA
8.
Zh Obshch Biol ; 56(6): 645-61, 1995.
Artigo em Russo | MEDLINE | ID: mdl-8546013

RESUMO

Nucleotide sequence of 23S-5S chloroplast rDNA spacer region including 4.5S rRNA gene of several dozens of seed plants was determined. The data obtained were used to construct phylogenetic trees and to compare them with the analogous data from literature. Topologies of trees constructed for various types of macromolecules and by different methods demonstrate obvious similarities although they are not identical. Some clue stages of seed plants evolution still remain obscure. Critical analysis of all the available information allows to come to several more or less definite conclusions. All the data say that angiosperms are a monophyletic group which diversified far before their fossils are definitely registered, i.e., before lower Cretaceous. Ancestral angiosperms were not genealogicaly related to modern woody Magnoliales but were represented by "paleoherbs", i. e. herbaceous and semiherbaceous magnoliids and monocots. Monocots originated at the earliest stages of angiosperms evolution and are not, probably, monophyletic. Woody Magnoliales and eudicots with tricolpate pollen seem to appear later in evolution. The conclusion that Gnetales is a sister group to angiosperms does not find enough support in molecular studies. Summing up, it looks as if a long period of existence of angiophytes preceded the pre-Cretaceous angiosperms irradiation. This line of development originated simultaneously with phylogenetic lineages of modern gymnosperms.


Assuntos
Evolução Molecular , Plantas/genética , Sequência de Bases , Dados de Sequência Molecular , Plantas/enzimologia , Sondas RNA , RNA de Plantas/genética , RNA Ribossômico/genética
12.
Mikrobiologiia ; 63(4): 668-82, 1994.
Artigo em Russo | MEDLINE | ID: mdl-7845250

RESUMO

A spheric thermoacidophilic sulphur-oxidizing archaebacterium (strain Str6kar) has been isolated from the hydrotherm of the Yellowstone National Park (USA). The isolate is a facultative autotroph. The strain Str6kar oxidizes elemental sulfur, ferrous sulfate and sulphide minerals, it is capable of using some organic compounds. The isolate grows at the temperature of 40-80 degrees. The content of GC-pairs in the DNA of the bacterium is 44.6 mol%. The level of homology of the isolates DNA for the Str6kar and Sulfurococcus mirabilis is 12-15%, for Str6kar and Metallosphaera sedula-0.7-7%. According to the structure of the 5s rRNA, the described bacteria are similar to S. mirabilis. Basing on morphological, physiological and molecular-genetical features, this archaeobacterium can be presented as a new species of the genus of Sulfurococcus-S. yellowstonii sp. nov.


Assuntos
Ácidos/metabolismo , Archaea/metabolismo , Ferro/metabolismo , Enxofre/metabolismo , Temperatura , Archaea/genética , Archaea/ultraestrutura , Composição de Bases , Sequência de Bases , DNA Bacteriano/análise , Dados de Sequência Molecular , Homologia de Sequência do Ácido Nucleico
15.
J Mol Evol ; 32(3): 253-61, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1904502

RESUMO

Complete or partial nucleotide sequences of five different rRNA species, coded by nuclear (18S, 5.8S, and 5S) or chloroplast genomes (5S, 4.5S) from a number of seed plants were determined. Based on the sequence data, the phylogenetic dendrograms were built by two methods, maximum parsimony and compatibility. The topologies of the trees for different rRNA species are not fully congruent, but they share some common features. It may be concluded that both gymnosperms and angiosperms are monophyletic groups. The data obtained suggest that the divergence of all the main groups of extant gymnosperms occurred after the branching off of the angiosperm lineage. As the time of divergence of at least some of these gymnosperm taxa is traceable back to the early Carboniferous, it may be concluded that the genealogical splitting of gymnosperm and angiosperm lineages occurred before this event, at least 360 million years ago, i.e., much earlier than the first angiosperm fossils were dated. Ancestral forms of angiosperms ought to be searched for among Progymnospermopsida. Genealogical relationships among gymnosperm taxa cannot be deduced unambiguously on the basis of rRNA data. The only inference may be that the taxon Gnetopsida is an artificial one, and Gnetum and Ephedra belong to quite different lineages of gymnosperms. As to the phylogenetic position of the two Angiospermae classes, extant monocotyledons seem to be a paraphyletic group located near the root of the angiosperm branch; it emerged at the earliest stages of angiosperm evolution. We may conclude that either monocotyledonous characters arose independently more than once in different groups of ancient Magnoliales or that monocotyledonous forms rather than dicotyledonous Magnoliales were the earliest angiosperms. Judging by the rRNA trees, Magnoliales are the most ancient group among dicotyledons. The most ancient lineage among monocotyledons leads to modern Liliaceae.


Assuntos
Filogenia , Plantas/genética , RNA Ribossômico/genética , Sequência de Bases , Evolução Biológica , Cloroplastos , Dados de Sequência Molecular , RNA Ribossômico 18S/genética , RNA Ribossômico 5,8S/genética , RNA Ribossômico 5S/genética , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico
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