Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Mater Sci Eng C Mater Biol Appl ; 109: 110573, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32228937

RESUMO

Implant associated infections can result in devastating consequences for patients. One major cause is the formation of bacterial biofilms, which result in increased resistance against antimicrobial therapeutics. A reduction of implant associated infections can be achieved by functionalization of implant surfaces. The generation of three dimensional surface structures by femtosecond laser ablation is one method to fabricate bacterial repellent large scaled surfaces without altering the material chemical composition. The challenge is to reduce bacterial growth while improving cellular ongrowth. For this purpose, spike structures were created as small as possible by used fabrication method on cubic Ti90/Al6/V4-rods and their effectiveness against bacterial colonization was compared to unstructured Ti90/Al6/V4-rods. Rods were implanted in the rat tibia and infected intraoperatively with 103 CFU of Staphylococcus aureus. Besides clinical behaviour and lameness, the vital bacterial biomass, morphological appearance and the volume of eukaryotic cells were determined on the implant surface after 21 days. Bone alterations were examined by radiological and histological techniques. Unexpectedly, the laser-structured implants did not show a lower bacterial load on the implant surface and less severe infection related bone and tissue alterations compared to the group without structuring. Simultaneously, a better bony integration and a higher cellular colonization with eukaryotic cells was detected on the laser-structured implants. These findings don't support the previous in vitro results. Nevertheless, the strong integration into the bone is a powerful argument for further surface modifications focussing on the improvement of the antibacterial effect. Additionally, our results underline the need for in vivo testing of new materials prior to clinical use.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Implantes Experimentais/microbiologia , Infecções Relacionadas à Prótese , Infecções Estafilocócicas , Staphylococcus aureus/fisiologia , Animais , Aderência Bacteriana/efeitos dos fármacos , Lasers , Masculino , Infecções Relacionadas à Prótese/tratamento farmacológico , Infecções Relacionadas à Prótese/metabolismo , Infecções Relacionadas à Prótese/patologia , Ratos , Ratos Endogâmicos Lew , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/metabolismo , Infecções Estafilocócicas/patologia , Uracila/análogos & derivados
2.
Vestn Otorinolaringol ; 82(5): 36-39, 2017.
Artigo em Russo | MEDLINE | ID: mdl-29072661

RESUMO

The objective of the present work was to study the relationship between the dimensions of the ethmoidal labyrinth and the skull in the subjects differing in the nose shape by means of the factorial and correlation analysis with the application of the modern computer-assisted methods for the three-dimensional reconstruction of the skull. We developed an original method for computed craniometry with the use the original program that made it possible to determine the standard intravital craniometrics characteristics of the human skull with a high degree of accuracy based on the results of analysis of 200 computed tomograms of the head. It was shown that the length of the inferior turbinated bones and the posterior edge of the orbital plate is of special relevance for practically all parameters of the ethmoidal labyrinth. Also, the width of the choanae positively relates to the height of the ethmoidal labyrinth.


Assuntos
Osso Etmoide , Adulto , Precisão da Medição Dimensional , Osso Etmoide/anatomia & histologia , Osso Etmoide/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Federação Russa , Estatística como Assunto , Tomografia Computadorizada por Raios X/métodos
3.
Dokl Biol Sci ; 464: 239-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26530066

RESUMO

By means of SEM, it has been demonstrated that structural coloration of the needletail Hirundapus caudacutus depends on architectonics of iridescent feathers of the bird.


Assuntos
Plumas/ultraestrutura , Animais , Aves , Plumas/química , Iridescência , Pigmentação
6.
Biofouling ; 28(6): 539-50, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22686938

RESUMO

Superhydrophobic titanium surfaces fabricated by femtosecond laser ablation to mimic the structure of lotus leaves were assessed for their ability to retain coccoid bacteria. Staphylococcus aureus CIP 65.8T, S. aureus ATCC 25923, S. epidermidis ATCC 14990T and Planococcus maritimus KMM 3738 were retained by the surface, to varying degrees. However, each strain was found to preferentially attach to the crevices located between the microscale surface features. The upper regions of the microscale features remained essentially cell-free. It was hypothesised that air entrapped by the topographical features inhibited contact between the cells and the titanium substratum. Synchrotron SAXS revealed that even after immersion for 50 min, nano-sized air bubbles covered 45% of the titanium surface. After 1 h the number of cells of S. aureus CIP 65.8T attached to the lotus-like titanium increased to 1.27×10(5) mm(-2), coinciding with the replacement of trapped air by the incubation medium.


Assuntos
Ar , Aderência Bacteriana/fisiologia , Cocos Gram-Positivos/fisiologia , Interações Hidrofóbicas e Hidrofílicas , Lotus/microbiologia , Titânio/química , Lotus/química , Folhas de Planta/química , Folhas de Planta/microbiologia , Análise Espectral Raman , Propriedades de Superfície
7.
Izv Akad Nauk Ser Biol ; (4): 436-46, 2011.
Artigo em Russo | MEDLINE | ID: mdl-21870493

RESUMO

The results of comparative electron microscope study of the fine structure of the definitive contour feathers often Crows species (Perisoreus infaustus, Garrulus glandarius, Cyanopica cyanus, Pica Pica, Podoceus panderi, Nucifraga caryocatactes, Corvus monedula, C. frugilegus, C. cornix, C. corax) are presented. The results of the research allowed us to conclude that crows, along with the traditional elements of feather architectonics, have a number of species-specific microstructure characteristics that are taxonomically important.


Assuntos
Plumas/ultraestrutura , Passeriformes/anatomia & histologia , Animais , Corvos/anatomia & histologia , Microscopia Eletrônica , Especificidade da Espécie
9.
Izv Akad Nauk Ser Biol ; (2): 133-41, 2006.
Artigo em Russo | MEDLINE | ID: mdl-16634429

RESUMO

The ultrastructure of liver cells was studied in rooks (Corvus frugilegus) living in radioactive and chemical contamination areas. The ultrastructure of liver cells from rook as well as jackdaw (Corvus monedula) and hooded crow (Corvus cornix) (Corvidae family) from a conventionally clean area was studied as control. Control hepatocytes proved to contain a great number of mitochondria, many of which were swollen and had clear matrix and disorganized cristae. The cristae nearly lacked glycogen and had abundant lipid droplets, which often tightly contacted mitochondria. The cytoplasm of hepatocytes in birds from both ecologically unfavorable areas had numerous mitochondria with the same ultrastructure. In contrast to control, the hepatocyte cytoplasm: (1) contained a lot of glycogen; (2) there were many lipid droplets, which directly contacted glycogen granules; and (3) had more abundant peroxisomes. In addition to normal erythrocytes, the sinusoids contained erythrocytes with mitochondria, vesicles, and lipid droplets in their cytoplasm. Analysis of many micrographs of lipid droplets contacting glycogen granules, mitochondria, peroxisomes, and cisterns of smooth endoplasmic reticulum allowed us to propose that glycogen is synthesized via gluconeogenesis from glycerol and products of fatty acid oxidation in the liver cell cytoplasm of rooks from ecologically unfavorable areas as distinct from control.


Assuntos
Corvos/anatomia & histologia , Poluição Ambiental , Hepatócitos/ultraestrutura , Fígado/citologia , Animais , Ecologia , Eritrócitos/ultraestrutura , Fígado/ultraestrutura , Glicogênio Hepático/ultraestrutura , Mitocôndrias Hepáticas/ultraestrutura , Dilatação Mitocondrial , Poluentes Radioativos/toxicidade
11.
Vestn Oftalmol ; 116(2): 7-9, 2000.
Artigo em Russo | MEDLINE | ID: mdl-11055212

RESUMO

Methods for conjunctival cavity plasty in anophthalmia and their advantages and drawbacks are discussed. The known methods do not always bring about satisfactory results (ensure a stable position of the prosthesis in the cavity). A method for conjunctival cavity formation with latex expanders is proposed. Original designs of expanders for the conjunctival cavity were used. The method is interesting and promising for conjunctival cavity plasty in anophthalmia when the cavity is shrunk.


Assuntos
Anoftalmia/cirurgia , Túnica Conjuntiva/cirurgia , Dispositivos para Expansão de Tecidos , Anestesia Geral , Túnica Conjuntiva/lesões , Humanos , Látex , Procedimentos Cirúrgicos Oftalmológicos/instrumentação , Procedimentos Cirúrgicos Oftalmológicos/métodos , Cuidados Pós-Operatórios , Técnicas de Sutura , Fatores de Tempo , Expansão de Tecido/instrumentação , Expansão de Tecido/métodos
15.
Med Tr Prom Ekol ; (2): 21-4, 1994.
Artigo em Russo | MEDLINE | ID: mdl-7953135

RESUMO

Female textile workers and women engaged into nonindustrial work were subjected to the examination including myometrium contractility, vegetative regulation, serum sex steroids level, some biochemical and histochemical parameters. The observed features of myometrium contractility in female textile workers were proved to associate with overactive vegetative regulation, hormonal disbalance and changes in some biochemical and histochemical parameters.


Assuntos
Miométrio/fisiologia , Doenças Profissionais/diagnóstico , Indústria Têxtil , Contração Uterina , Adulto , Doenças do Sistema Nervoso Autônomo/diagnóstico , Feminino , Hormônios Esteroides Gonadais/sangue , Humanos , Ciclo Menstrual , Doenças Profissionais/sangue
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...