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1.
Mater Sci Eng C Mater Biol Appl ; 69: 922-32, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27612787

RESUMO

Novel nanohybrids consisting of nano-Ag, chitosan, lipids and phyto-compounds (chlorophyll a and curcumin) have been achieved through a simple bottom-up strategy, resulting in stable (ZP=-30.9mV) and spherical-shaped nano-entities with size <200nm (estimated by AFM analysis and DLS measurements). The formation of these biohybrids was monitored by absorption and emission spectroscopy, exploiting the spectral fingerprint of chlorophyll a. The bio-performances of these hybrid materials such as: high antioxidant activity (96.63%), strong biocidal properties against Escherichia coli ATCC 8738 (exhibiting an inhibition zone diameter of 32mm), hemocompatibility, in vitro cytotoxicity against HT-29 cancer cells and no toxicity to normal cells (in the biohybrid concentration range of 5.7-17%), make them promising candidates in bio-applications (antimicrobial and antioxidant coating, cancer treatment).


Assuntos
Produtos Biológicos/química , Nanopartículas Metálicas/química , Prata/química , Animais , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Morte Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Clorofila/metabolismo , Clorofila A , Escherichia coli/efeitos dos fármacos , Ácido Fólico/química , Células HT29 , Hemólise/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/ultraestrutura , Camundongos , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Tamanho da Partícula , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
2.
J Nanosci Nanotechnol ; 16(6): 6332-7, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27427713

RESUMO

In a Surface Plasmon Resonance (SPR) experiment two key parameters are classically recorded: the time and the angle of SPR reflectivity. This paper brings into focus a third key parameter: SPR reflectivity. The SPR reflectivity is proved to be related to surface roughness changes. Practical investigations on (i) gold anodizing and (ii) polypyrrole film growth in presence of oxalic acid is detailed under potentiostatic conditions. These experimental results reveal the potential of using the SPR technique to investigate real-time changes both on the gold surface, but also in the gold film itself. This extends the versatility of the technique in particular as sensitive in-situ diagnostic tool.

3.
J Med Life ; 7(2): 177-82, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25184007

RESUMO

The practice of dentistry involves laborious high finesse dental preparations, precision and control in executions that require a particular attention, concentration and patience of the dentist and finally the dentist's physical and mental resistance. The optimal therapeutic approach and the success of practice involve special working conditions for the dentist and his team in an ergonomic environment. The meaning of the posture in ergonomics is the manner in which different parts of the body are located and thus the reports are established between them in order to allow a special task execution. This article discusses the posture adopted by dentists when they work, beginning with the balanced posture and going to different variants of posture. The ideal posture of a dentist gives him, on the one hand the optimal working conditions (access, visibility and control in the mouth) and on the other hand, physical and psychological comfort throughout the execution of the clinical acts. Although the theme of dentist posture is treated with great care and often presented in the undergraduate courses and the continuing education courses on ergonomics in dentistry, many dentists do not know the subject well enough nor the theoretical issues and therefore nor the practical applicability. The risk and perspective of the musculoskeletal disorders related to unbalanced postures should determine the dentists take postural corrective actions and compensation measures in order to limit the negative effects of working in a bad posture.


Assuntos
Odontologia/métodos , Odontólogos , Ergonomia/métodos , Saúde Ocupacional/normas , Equilíbrio Postural/fisiologia , Postura/fisiologia , Humanos
4.
Bioelectrochemistry ; 79(1): 122-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20189888

RESUMO

The paper is a new approach which aims to evaluate the relation between surface aspects (wettability and roughness) of materials based on titanium with native passive TiO(2) as untreated samples and TiO(2) nanotubes as treated discs respectively, their electrochemical stability in artificial saliva, and fibroblast cell behavior. Ti/TiO(2) modified electrodes as nanotubes with 120 nm as diameter were obtained using an electrochemical method as anodizing and surface analysis as SEM, AFM and contact angle measurements were performed to obtain topographical features and wettability. The TiO(2) nanotube structured oxide films electrochemical growth increases the stability of titanium surfaces. The electrochemical behavior of the Ti/TiO(2) nanotube surface was evaluated by corrosion parameters obtained from Tafel plots and electrical parameters for proposed circuits from electrochemical impedance spectroscopy were analyzed. The cell results indicated a slight preference in terms of cell survival and adhesion for nanostructure TiO(2) with a more hydrophilic character and the electrochemical data revealed that such features are connected with better stability in artificial saliva. The roughness seems to be not conclusive for this case.


Assuntos
Nanotubos , Saliva Artificial/química , Titânio/química , Titânio/farmacologia , Actinas/metabolismo , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Implantes Dentários , Eletroquímica , Eletrodos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Saliva Artificial/metabolismo , Propriedades de Superfície , Molhabilidade/efeitos dos fármacos
5.
Histopathology ; 35(5): 401-10, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10583554

RESUMO

AIMS: The purpose of the study is to evaluate histological measurement methods for quantitative assessment of the degree of tubular differentiation in breast cancer. METHODS AND RESULTS: We evaluated tubular differentiation in 20 cases of invasive breast cancer by four different assessment methods. Method 1 was the traditional subjective evaluation of the amount of malignant tubules in each sample. Method 2 evaluated the fraction of fields presenting tubular differentiation by registering the presence or absence of neoplastic tubular structures in each microscopic field. In method 3 the area fraction of malignant epithelial cells presenting tubular differentiation was assessed field-by-field and expressed as an average of the whole tumour area. Method 4 applied point counting for evaluating the fraction of malignant epithelial cells in tubular structures. By correlation and reproducibility analyses, method 1 was inferior to the other methods. Method 4 was accurate but too laborious and time-consuming for clinical use. Methods 2 and 3 were both efficient and reproducible and could be used interchangeably. With the time and effort used in the measurements taken into consideration method 2 was best applicable to clinical practice. CONCLUSION: Accurate evaluation of tubular differentiation in breast cancer is possible by defining the presence or absence of tubular differentiation in microscopic fields of a histological section. Assessment of the fraction of fields with tubular differentiation (FTD) is simple, unambiguous, objective and fast--even a large sample can be screened in less than 10 min. In our results, FTD has clear advantages over subjective or point counting-based evaluation methods of tubular differentiation.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Diferenciação Celular , Estudos de Avaliação como Assunto , Feminino , Humanos , Prognóstico , Reprodutibilidade dos Testes
6.
Artigo em Romano | MEDLINE | ID: mdl-2518584

RESUMO

The authors followed the efficiency of product Macronil in association with the usual (antibiotic and symptomatic) treatments in acute, viral respiratory infections in 62 children, 0-5 years old, admitted into hospital. Besides the usual treatment (25 cases--control group) Macronil was administered in 37 cases (experimental group). A significant improvement was found in clinical evolution (duration of disease evolution, improvement of general state, good appetite, fever duration, increase in weight) of the experimental group versus the control group. An important reduction (twice) of the pharyngeal viral population appeared in the experimental group treated with Macronil. In the control group, the viral flora, remained, practically, the same after treatment.


Assuntos
Antivirais/uso terapêutico , Infecções Respiratórias/tratamento farmacológico , Extratos de Tecidos/uso terapêutico , Doença Aguda , Animais , Pré-Escolar , Avaliação de Medicamentos , Quimioterapia Combinada , Peixes , Humanos , Lactente , Recém-Nascido , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/microbiologia , Infecções Respiratórias/microbiologia
7.
Virologie ; 34(2): 83-7, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6308887

RESUMO

The presence of viral (herpes 1 and 2, influenza A and B, parainfluenza 1, 2, and 3, adenovirus) and inframicrobial (Chlamydia, R. burneti and mycoplasma) antigens was investigated by indirect immunofluorescence reaction in exfoliated cells from 107 patients with chronic eye diseases and 77 patients with chronic respiratory diseases. Single or associated viral or inframicrobial antigens were detected in 80% of the former and in 60% of the latter patients. The proportion of multiple infections was of about 60% in both patient groups.


Assuntos
Infecções Bacterianas/diagnóstico , Oftalmopatias/etiologia , Imunofluorescência , Infecções Respiratórias/etiologia , Viroses/diagnóstico , Infecções por Adenovirus Humanos/diagnóstico , Antígenos de Bactérias/análise , Antígenos Virais/análise , Infecções por Chlamydia/diagnóstico , Humanos , Influenza Humana/diagnóstico , Ceratite Dendrítica/diagnóstico , Infecções por Mycoplasma/diagnóstico , Infecções por Paramyxoviridae/diagnóstico , Infecções por Rickettsia/diagnóstico
8.
Virologie ; 33(2): 123-32, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6293164

RESUMO

Mouse Ehrlich ascites carcinoma (EAC) cells proved to be a semipermissive substrate for in vivo cultivation of adenovirus 5 (Ad5) and SV40. The multiplication of SV40 in EAC cells was facilitated by the coinfection with Ad5. As demonstrated by ID and EID reactions, the virus progens isolated at the first passage after the mixed infection of EAC cells with Ad5 and SV40 possess an antigenic mosaic with fractions characteristic of the parental viruses and of the cell substrate in which they had cultivated in vitro and in vivo. The progens gave positive seroneutralization and complement fixation reactions only with antiserum to SV40.


Assuntos
Adenovírus Humanos/crescimento & desenvolvimento , Vírus 40 dos Símios/crescimento & desenvolvimento , Cultura de Vírus , Adenovírus Humanos/isolamento & purificação , Animais , Antígenos Virais/análise , Líquido Ascítico/microbiologia , Carcinoma de Ehrlich , Células Cultivadas , Hibridização Genética , Camundongos , Vírus 40 dos Símios/isolamento & purificação
9.
Artigo em Romano | MEDLINE | ID: mdl-128804

RESUMO

The phenomenon of endointestinal protein exudation in acute infectious enterocolitis is studied. Total proteins were determined in 30 cases of acute enterocolitis and 50 of bacillary dysentery in the acute stages of the disease and convalescence. The proteinogram of the jejunal juice was performed in the acute stage and convalescence in 20 patients. In 16 patients and 5 controls endointestinal albumin elimination was determined quantitatively by means of 131I labeled albumin. The results showed increase in the total protein content in the jejunal juice in the course of acute infectious enterocolitis and bacillary dysentery and a return to normal values in convalescence. Electrophoresis of the jejunal juice in acute infectious enterocolitis showed the absence of fraction III with alpha1-globulin migration, and increased fractions I, II and IV probably due to the loss of endointestinal albumin, also confirmed by quantitative albumin determinations with 131I labeled albumin. In conclusion, patients with acute infectious enterocolitis present a marked loss of endointestinal albumins in the acute stage of the disease, with a return to normal values in convalescence.


Assuntos
Disenteria Bacilar/complicações , Enterocolite Pseudomembranosa/complicações , Secreções Intestinais , Enteropatias Perdedoras de Proteínas , Albuminas/análise , Humanos , Secreções Intestinais/análise , Jejuno
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