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1.
Rev Med Liege ; 69 Suppl 1: 75-80, 2014.
Artigo em Francês | MEDLINE | ID: mdl-24822310

RESUMO

Non-small cell lung cancer (NSCLC) is common. Approximately one out of every five patients with NSCLC has locally advanced disease that is surgically unresectable. For these patients, the disease has a poor prognosis characterized by a high rate of local disease progression or recurrence despite attempts at chemo- and radiation therapy. The purpose of this review is to describe the heterogeneity of this group of patients, to clarify the terms of the combination of chemotherapy and radiotherapy and to clarify the efficacy of modern radiotherapy techniques to increase local control.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/terapia , Quimiorradioterapia/métodos , Neoplasias Pulmonares/terapia , Carcinoma Pulmonar de Células não Pequenas/patologia , Terapia Combinada , Progressão da Doença , Humanos , Neoplasias Pulmonares/patologia , Recidiva Local de Neoplasia , Prognóstico
2.
Analyst ; 136(5): 1018-22, 2011 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-21165476

RESUMO

In the investigation of chemical pollutants, such as PAHs (Polycyclic Aromatic Hydrocarbons) at low concentration in aqueous medium, Surface-Enhanced Raman Scattering (SERS) stands for an alternative to the inherent low cross-section of normal Raman scattering. Indeed, SERS is a very sensitive spectroscopic technique due to the excitation of the surface plasmon modes of the nanostructured metallic film. The surface of quartz substrates was coated with a hydrophobic film obtained by silanization and subsequently reacted with polystyrene (PS) beads coated with gold nanoparticles. The hydrophobic surface of the SERS substrates pre-concentrates non-polar molecules such as naphthalene. Under laser excitation, the SERS-active substrates allow the detection and the identification of the target molecules localized close to the gold nanoparticles. The morphology of the SERS substrates based on polystyrene beads surrounded by gold nanoparticles was characterized by scanning electron microscopy (SEM). Furthermore, the Raman fingerprint of the polystyrene stands for an internal spectral reference. To this extent, an innovative method to detect and to quantify organic molecules, as naphthalene in the range of 1 to 20 ppm, in aqueous media was carried out. Such SERS-active substrates tend towards an application as quantitative SERS sensors for the environmental analysis of naphthalene.

3.
Langmuir ; 24(21): 12272-81, 2008 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-18839968

RESUMO

Biofouling of all structures immersed in seawater constitutes an important problem, and many strategies are currently being developed to tackle it. In this context, our previous work shows that poly(ethylene glycol) monoacrylate (PEGA) macromonomer grafted on preoxidized poly(methyl methacrylate) (PMMAox) films exhibits an excellent repellency against the bovine serum albumin used as a model protein. This study aims to evaluate the following: (1) the prevention of a marine extract material adsorption by the modified surfaces and (2) the antifouling property of the PEGA-g-PMMAox substrates when immersed in natural seawater during two seasons (season 1: end of April-beginning of May 2007, and season 2: end of October-beginning of November 2007). The antifouling performances of the PEGA-g-PMMAox films are investigated for different PEG chain lengths and macromonomer concentrations into the PEGA-based coatings. These two parameters are followed as a function of the immersion time, which evolves up to 14 days. The influence of the PEGA layer on marine compounds (proteins and phospholipids) adsorption is evidenced by time-of-flight secondary ion mass spectrometry (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS). It was found that the antifouling efficiency of the PEGA-grafted surfaces increases with both PEGA concentration and PEG chain length.

4.
J Appl Microbiol ; 105(3): 791-9, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18489561

RESUMO

AIMS: The nature of exopolymers involved in the adhesion of a marine biofilm-forming bacterium Pseudoalteromonas sp. D41 was investigated to evaluate and understand the antifouling potential of subtilisin. METHODS AND RESULTS: The exopolymers of D41 produced by fermentation were analysed by FTIR and SDS-PAGE showing the presence of polysaccharides, glycoproteins and proteins. A high content of proteins was detected both in soluble and capsular fractions. The microscopic observations of fluorescamine and calcofluor stained adhered D41 indicated mainly the presence of proteins in exopolymers produced during adhesion. Subtilisin, the broad spectrum protease, tested in natural sea water and in polystyrene microplates showed that antifouling activity was higher in the prevention of bacterial adhesion than in the detachment of adhered D41 cells. CONCLUSIONS: Overall, these results demonstrate the involvement of proteins in Pseudoalteromonas sp. D41 adhesion and confirm the high antifouling potential of subtilisin. SIGNIFICANCE AND IMPACT OF THE STUDY: This study emphasizes the major role of proteins instead of polysaccharides, thus extending our knowledge regarding the nature of extracellular polymers involved in bacterial adhesion. Furthermore, the high antifouling potential of subtilisin evaluated in the very first stages of fouling, bacterial adhesion, could lead to less toxic compounds than organometallic compounds in antifouling paint.


Assuntos
Proteínas/metabolismo , Pseudoalteromonas/fisiologia , Subtilisina/farmacologia , Microbiologia da Água , Aderência Bacteriana/efeitos dos fármacos , Técnicas Bacteriológicas , Biofilmes , Hidrólise , Polímeros , Pseudoalteromonas/efeitos dos fármacos , Pseudoalteromonas/metabolismo , Água do Mar
5.
Biofouling ; 24(1): 11-22, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18058451

RESUMO

The antifouling potential of commercial hydrolases, four proteases, seven glycosidases and one lipase was evaluated on the adhesion of marine Pseudoalteromonas sp. D41. The experimental method, adapted to screen antifouling agents, was based on bacterial adhesion in natural sterile sea water in a microtiter plate and on total biomass quantification by the fluorescent dye DAPI (4[prime]6-diamidino-2-phenylindole). Savinase (subtilisin) was the most effective hydrolase in both the prevention of bacterial adhesion and the removal of adhered bacteria. However, some enzymatic preparations tested such as Amano protease were not only ineffective but also increased the number of adhered bacterial cells. Enumeration using epifluorescence microscopy of CTC (5-cyano-2,3-ditolyl tetrazolium chloride) and DAPI stained adhered D41 cells confirmed these observations. Overall, these results demonstrated that hydrolases could either prevent adhesion and remove adhered bacterial cells effectively, or conversely increase bacterial adhesion, depending on enzymatic concentrations and the type of enzymes tested.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Glicosídeo Hidrolases/farmacologia , Lipase/farmacologia , Peptídeo Hidrolases/farmacologia , Pseudoalteromonas/efeitos dos fármacos , Subtilisina/farmacologia , Microscopia de Fluorescência , Praguicidas/farmacologia , Poliestirenos , Água do Mar/microbiologia , Serina Endopeptidases/farmacologia , Microbiologia da Água
6.
Lett Appl Microbiol ; 44(4): 372-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17397474

RESUMO

AIMS: To develop a method to screen antifouling agents against marine bacterial adhesion as a sensitive, rapid and quantitative microplate fluorescent test. METHODS AND RESULTS: Our experimental method is based on a natural biofilm formed by mono-incubation of the marine bacterium Pseudoalteromonas sp. D41 in sterile natural sea water in a 96-well polystyrene microplate. The 4'6-diamidino-2-phenylindole dye was used to quantify adhered bacteria in each well. The total measured fluorescence in the wells was correlated with the amount of bacteria showing a detection limit of one bacterium per 5 microm(2) and quantifying 2 x 10(7) to 2 x 10(8) bacteria adhered per cm(2). The antifouling properties of three commercial surface-active agents and chlorine were tested by this method in the prevention of adhesion and also in the detachment of already adhered bacteria. The marine bacterial adhesion inhibition rate depending on the agent concentration showed a sigmoid shaped dose-response curve. CONCLUSIONS: This test is well adapted for a rapid and quantitative first screening of antifouling agents directly in seawater in the early steps of marine biofilm formation. SIGNIFICANCE AND IMPACT OF THE STUDY: In contrast to the usual screenings of antifouling products which detect a bactericidal activity, this test is more appropriate to screen antifouling agents for bacterial adhesion removal or bacterial adhesion inhibition activities. This screening test focuses on the antifouling properties of the products, especially the initial steps of marine biofilm formation.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Pseudoalteromonas/fisiologia , Água do Mar/microbiologia , Tensoativos/farmacologia , Bactérias/crescimento & desenvolvimento , Cloro/farmacologia , Contagem de Colônia Microbiana , Relação Dose-Resposta a Droga , Corantes Fluorescentes , Indóis , Concentração Inibidora 50 , Microscopia de Fluorescência , Sensibilidade e Especificidade
7.
Biosens Bioelectron ; 21(7): 1355-8, 2006 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-16009543

RESUMO

We report the immobilization on a gold surface of a 20-base DNA probe labeled with disulfide group and on the selective hybridization with the complementary 20-base DNA strand. The oligonucleotide probe is the complementary strand of a partial sequence of the gene encoding for a large ribosomal RNA sub-unit which is a coding sequence of Alexandrium minutum DNA, a microalgae that produces neurotoxins responsible for paralytic shellfish poisoning on European and Asian coasts. The kinetics of DNA probe immobilization and hybridization were monitored in situ by using a 27 MHz quartz crystal microbalance under controlled hydrodynamic conditions. The frequency of the setup is stable to within a few hertz, corresponding to the nanogram scale, for 3h and makes it possible to follow frequency change from immobilization of the probe to hybridization of the complementary DNA target. This setup constitutes a biosensor, which is sensitive and selective, and the hybridization ratio between hybridized complementary DNA and immobilized DNA probes is 47%.


Assuntos
Técnicas Biossensoriais/instrumentação , DNA de Algas/análise , DNA de Algas/genética , Dinoflagellida/genética , Eletroquímica/instrumentação , Hibridização In Situ/instrumentação , Análise de Sequência com Séries de Oligonucleotídeos/instrumentação , Animais , Técnicas Biossensoriais/métodos , Eletroquímica/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Hibridização In Situ/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Quartzo , Transdutores
8.
J Phys Chem B ; 109(19): 9540-9, 2005 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-16852148

RESUMO

Adhesion of bacterial strains on solid substrates is likely related to the properties of the outer shell of the micro-organisms. Aiming at a better understanding and control of the biofilm formation in seawater, the surface chemical composition of three marine bacterial strains was investigated by combining Fourier transform IR spectroscopy, X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary-ion mass spectrometry (ToF-SIMS). The D41 strain surface showed evidence of proteins, as deduced from the NH2 and NCO XPS and ToF-SIMS fingerprints; this strain was found to adhere to stainless steel, glass, or Teflon surfaces in a much higher quantity (2 orders of magnitude) than the two other ones, DA and D01. The latter are either enriched in COOH or sulfates, and this makes them more hydrophilic and less adherent to all substrates. Correlations with physicochemical properties and adhesion seem to demonstrate the role of the external layer composition, in particular the role of proteins more than that of hydrophobicity, on their adhesion abilities.


Assuntos
Bactérias/química , Aço Inoxidável/química , Adesividade , Alteromonas/química , Alteromonas/ultraestrutura , Bactérias/ultraestrutura , Liofilização , Congelamento , Espectrometria de Massas , Microscopia de Fluorescência , Nitrogênio/química , Oxigênio/química , Pseudomonas/química , Pseudomonas/ultraestrutura , Água do Mar , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral , Enxofre/química , Propriedades de Superfície , Vibrio/química , Vibrio/ultraestrutura , Raios X
9.
J Microbiol Methods ; 48(2-3): 195-205, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11777569

RESUMO

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) has been employed to study the biofouling of stainless steel samples immersed in seawater. The aim of these characterisations was to understand the initial mechanisms of biomolecule adsorption for relatively short immersion times (from 0 to 24 h). The results show that: (i) there were unavoidable sample "precontaminations" on the surfaces, despite precaution during their preparation and manipulation (washing, drying and storing); (ii) the major peaks detected were the substrate ones whatever the immersion time [However, some organic (nitrogen and oxygen containing) and inorganic secondary ions appeared and grew with the immersion time.]; (iii) the surface contaminations, the nonuniformity of the adsorbed material so as and bacteria have been clearly observed by high-lateral resolution molecular ToF-SIMS mapping.


Assuntos
Bactérias/química , Proteínas/análise , Espectrometria de Massa de Íon Secundário , Aço Inoxidável , Microbiologia da Água , Bactérias/isolamento & purificação , Água do Mar
10.
Rev Med Liege ; 56(9): 599-606, 2001 Sep.
Artigo em Francês | MEDLINE | ID: mdl-11702501

RESUMO

Uncommon but classically described, intestinal carcinoid tumors represent a variety of neuroendocrine tumors. Able to secrete amines and hormones, they can produce characteristic symptoms called "carcinoïd syndrome". A cardiopathy is sometimes associated with the disease and carries a high risk of mortality and morbidity.


Assuntos
Doença Cardíaca Carcinoide/etiologia , Neoplasias Intestinais/complicações , Idoso , Doença Cardíaca Carcinoide/patologia , Diagnóstico Diferencial , Ecocardiografia , Feminino , Humanos , Intestino Delgado/patologia , Prognóstico
17.
Clin Orthop Relat Res ; (160): 78-85, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7285441

RESUMO

The case of a young adult female who developed multiple orthopedic problems associated with genetic osteomalacia is presented. Pathologically in the subcapital regions of both proximal femurs severe osteomalacic callus through stress fractures was demonstrated.


Assuntos
Fraturas do Fêmur/complicações , Osteomalacia/complicações , Fosfatos/sangue , Vitamina D/uso terapêutico , Adulto , Feminino , Fraturas do Fêmur/patologia , Fraturas do Fêmur/cirurgia , Cabeça do Fêmur/diagnóstico por imagem , Cabeça do Fêmur/patologia , Prótese de Quadril , Humanos , Osteomalacia/tratamento farmacológico , Radiografia
18.
AJR Am J Roentgenol ; 134(5): 971-7, 1980 May.
Artigo em Inglês | MEDLINE | ID: mdl-6768275

RESUMO

The radiographic manifestations of musculoskeletal stress at the elbow associated with racket and throwing sports are reported in 29 symptomatic amateur, juvenile, and professional athletes. Five major categories of stress are identified: diffuse, humeral shaft, medial tension, lateral compression, and extension stress. The osseous changes produced by these stresses include bony hypertrophy, loose bodies, traction spur formation, osteochondral and humeral shaft fractures in the adult, and epiphyseal and apophyseal hypermaturity or avulsion in the youngster.


Assuntos
Traumatismos em Atletas/diagnóstico por imagem , Lesões no Cotovelo , Úmero/diagnóstico por imagem , Ulna/diagnóstico por imagem , Adolescente , Adulto , Idoso , Beisebol , Cartilagem Articular/lesões , Criança , Articulação do Cotovelo/diagnóstico por imagem , Feminino , Humanos , Fraturas do Úmero/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia , Tênis , Fraturas da Ulna/diagnóstico por imagem
19.
J Bone Joint Surg Am ; 61(5): 714-8, 1979 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-379006

RESUMO

Total patellectomy, although it has a biomechanical disadvantage in that it may lead to a degree of quadriceps weakness, is frequently indicated in selected patients. Numerous different techniques of performing patellectomy have been described. In this paper, we present a technique of performing a patellectomy in which the continuity of the quadriceps mechanism is not disrupted and the vastuc medialis is advanced. Twenty-six patients (twenty-nine knees) in whom the procedure was performed were studied retrospectively. The findings in this series showed 90 per cent good or excellent results, two cases of extensor lag, an average of 118 degrees of knee flexion, minimum quadriceps atrophy with good strength, and minimum postoperative immobilization. The method presented has the important advantage of an easier, smoother postoperative knee-rehabilitation period, which is extremely advantageous in elderly patients.


Assuntos
Cabeça do Fêmur , Articulação do Joelho/cirurgia , Osteoartrite/cirurgia , Patela/cirurgia , Transferência Tendinosa/métodos , Tendões/cirurgia , Adolescente , Adulto , Idoso , Estudos de Avaliação como Assunto , Feminino , Humanos , Articulação do Joelho/fisiopatologia , Masculino , Métodos , Pessoa de Meia-Idade , Osteoartrite/reabilitação , Cuidados Pós-Operatórios , Técnicas de Sutura
20.
Clin Orthop Relat Res ; (132): 46-52, 1978 May.
Artigo em Inglês | MEDLINE | ID: mdl-679551

RESUMO

By comparing estimates from several sources an assessment can be made of the number of total joint replacement procedures performed annually in the United States. Approximately 80,000 hips and 40,000 knee joints were replaced in the U.S. during 1976. Total hip replacement has been accepted by the orthopedic community as an efficacious mode of treatment of the many painful and disabling forms of arthritis. A substantial patient population could benefit from perfection of designs for treating joints other than the hip.


Assuntos
Prótese Articular , Articulação do Quadril/cirurgia , Humanos , Illinois , Articulação do Joelho/cirurgia , Estatística como Assunto , Estados Unidos
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