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1.
ChemSusChem ; 16(13): e202300103, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-36916487

RESUMO

The reductive catalytic fractionation (RCF) of lignocellulosic biomass is an attractive method for the conversion of lignin toward valuable low-molecular weight aromatics. A limitation to the upscaling of such technology is represented by the use ofpressurized hydrogen gas. Here, the role of hydrogen gas within the RCF of wheat straw biomass is investigated. The use of H2 is shown to enhance lignin depolymerization, by virtue of an improved hydrogenolysis and hydrogenation of lignin fragments, with a yield of phenolic monomers that increased from ca. 12 wt % of acid-insoluble lignin in the initial biomass under inert atmosphere to up to ca. 25 wt % under H2 (in methanol, at 250 °C, with Ru/C). The adoption of methanol, ethanol or isopropanol as hydrogen-donor solvents was also investigated in the absence of H2 . Ethanol was found to give the highest yield of monophenolic compounds (up to ≈20 wt %) owing to a better balance between solvolysis, hydrogenolysis, and hydrogenation of lignin. Nevertheless, a substantial loss of the carbohydrate fraction was observed. The use of a lower temperature (200 °C) in combination with H3 PO4 resulted in an improved recovery of cellulose in the pulp and in the solubilization of hemicellulose and lignin, with the formation of monosaccharides (≈14 wt % of polysaccharides in the initial biomass) and phenolic monomers (up to 18 wt %, in the absence of H2 ). Overall, a tradeoff exists between the removal of H2 from the process and the production of low-molecular weight phenolics during RCF.


Assuntos
Lignina , Triticum , Hidrogênio , Metanol , Biomassa , Etanol
2.
Bioengineering (Basel) ; 10(2)2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36829637

RESUMO

The lack of viability of massive bone allografts for critical-size bone defect treatment remains a challenge in orthopedic surgery. The literature has reviewed the advantages of a multi-combined treatment with the synergy of an osteoconductive extracellular matrix (ECM), osteogenic stem cells, and growth factors (GFs). Questions are still open about the need for ECM components, the influence of the decellularization process on the latter, the related potential loss of function, and the necessity of using pre-differentiated cells. In order to fill in this gap, a bone allograft surrounded by an osteogenic membrane made of a decellularized collagen matrix from human fascia lata and seeded with periosteal mesenchymal stem cells (PMSCs) was analyzed in terms of de-/recellularization, osteogenic properties, PMSC self-differentiation, and angiogenic potential. While the decellularization processes altered the ECM content differently, the main GF content was decreased in soft tissues but relatively increased in hard bone tissues. The spontaneous osteogenic differentiation was necessarily obtained through contact with a mineralized bone matrix. Trying to deepen the knowledge on the complex matrix-cell interplay could further propel these tissue engineering concepts and lead us to provide the biological elements that allow bone integration in vivo.

3.
Front Bioeng Biotechnol ; 10: 944828, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36338112

RESUMO

Introduction: The human fascia lata (HFL) is used widely in reconstructive surgery in indications other than fracture repair. The goal of this study was to compare microscopic, molecular, and mechanical properties of HFL and periosteum (HP) from a bone tissue engineering perspective. Material and Methods: Cadaveric HP and HFL (N = 4 each) microscopic morphology was characterized using histology and immunohistochemistry (IHC), and the extracellular matrix (ECM) ultrastructure assessed by means of scanning electron microscopy (SEM). DNA, collagen, elastin, glycosaminoglycans, major histocompatibility complex Type 1, and bone morphogenetic protein (BMP) contents were quantified. HP (N = 6) and HFL (N = 11) were submitted to stretch tests. Results: Histology and IHC highlighted similarities (Type I collagen fibers and two-layer organization) but also differences (fiber thickness and compaction and cell type) between both tissues, as confirmed using SEM. The collagen content was statistically higher in HFL than HP (735 vs. 160.2 µg/mg dry weight, respectively, p < 0.0001). On the contrary, DNA content was lower in HFL than HP (404.75 vs. 1,102.2 µg/mg dry weight, respectively, p = 0.0032), as was the immunogenic potential (p = 0.0033). BMP-2 and BMP-7 contents did not differ between both tissues (p = 0.132 and p = 0.699, respectively). HFL supported a significantly higher tension stress than HP. Conclusion: HP and HFL display morphological differences, despite their similar molecular ECM components. The stronger stretching resistance of HFL can specifically be explained by its higher collagen content. However, HFL contains many fewer cells and is less immunogenic than HP, as latter is rich in periosteal stem cells. In conclusion, HFL is likely suitable to replace HP architecture to confer a guide for bone consolidation, with an absence of osteogenicity. This study could pave the way to a bio-engineered periosteum built from HFL.

4.
Int. j. high dilution res ; 21: 67-84, June 20, 2022.
Artigo em Inglês | LILACS, HomeoIndex - Homeopatia | ID: biblio-1396376

RESUMO

Homeopathy is highly controversial. The main reason for this is its use of very highly dilute medicines (high homeopathic potencies, HHP), diluted beyond the Avogadro/Loschmidt limit. Research using Nano Tracking Analysis has demonstrated the presence of particles in HHPs. This study aims to verify the results of a previous publication that identified the ionic composition of these particles in all dilutions. We used Scanning Electron Microscopy & Energy Dispersive X-Ray Spectroscopy (SEM-EDX) to examine dilutions of a commonly used homeopathic medicine, an insoluble metal, Cuprum metallicum, for the presence of particles (NPs). The homeopathic medicines tested were specially prepared according to the European pharmacopoeia standards. We compared the homeopathic dilutions/dynamizations of copper with simple dilutions and dynamized lactose controls. We observed an ionic diversity common to all preparations including HHPs but also significant differences in the relative quantity of each ion between manufacturing lines of homeopathic copper and lactose controls. The probability that the observed differences could have occurred chance alone (especially above Avogadro limit) can be rejected at p < 0.001. The essential component of these homeopathic medicines is sodium hydrogen carbonate, modulated by some other elements and by its quantity, size and shape. Homeopathic medicines made of Cuprum metallicum do contain material with a specific ionic composition even in HHPs diluted beyond the Avogadro/Loschmidt limit. This specificity can be attributed to the manufacturing process. This material demonstrates that the step-by-step process (dynamized or not) does not match the theoretical expectations of a dilution process. The starting material and dilution/dynamization method influences the nature of these NPs. Further measurements are needed on other raw materials using the same controls (solvent and simply diluted manufacturing lines) to support these findings. The role of sodium bicarbonate must be carefully studied in the future.


Assuntos
Dinamização , Farmacotécnica Homeopática , Nanopartículas , Espectrometria por Raios X , Microscopia Eletrônica de Varredura , Cuprum Metallicum , Bicarbonato de Sódio , Cobre , Lactose
5.
Dent J (Basel) ; 7(4)2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31581536

RESUMO

Peri-implantitis (PI) is an inflammatory disease of peri-implant tissues, it represents the most frequent complication of dental implants. Evidence revealed that microorganisms play the chief role in causing PI. The purpose of our study is to evaluate the cleaning of contaminated dental implant surfaces by means of the Q-switch Nd:YAG (Neodymium-doped Yttrium Aluminum Garnet) laser and an increase in temperature at lased implant surfaces during the cleaning process. Seventy-eight implants (titanium grade 4) were used (Euroteknika, Sallanches, France). Thirty-six sterile implants and forty-two contaminated implants were collected from failed clinical implants for different reasons, independent from the study. Thirty-six contaminated implants were partially irradiated by Q-switch Nd:YAG laser (1064 nm). Six other contaminated implants were used for temperature rise evaluation. All laser irradiations were calibrated by means of a powermetter in order to evaluate the effective delivered energy. The irradiation conditions delivered per pulse on the target were effectively: energy density per pulse of 0.597 J/cm2, pick powers density of 56 mW/cm2, 270 mW per pulse with a spot diameter of 2.4 mm, and with repetition rate of 10 Hz for pulse duration of 6 ns. Irradiation was performed during a total time of 2 s in a non-contact mode at a distance of 0.5 mm from implant surfaces. The parameters were chosen according to the results of a theoretical modeling calculation of the Nd:YAG laser fluency on implant surface. Evaluation of contaminants removal showed that the cleaning of the irradiated implant surfaces was statistically similar to those of sterile implants (p-value ≤ 0.05). SEM analysis confirmed that our parameters did not alter the lased surfaces. The increase in temperature generated at lased implant surfaces during cleaning was below 1 °C. According to our findings, Q-switch Nd:YAG laser with short pulse duration in nanoseconds is able to significantly clean contaminated implant surfaces. Irradiation parameters used in our study can be considered safe for periodontal tissue.

6.
Nanoscale Adv ; 1(6): 2208-2215, 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-36131957

RESUMO

A process combining electrochemical nanofabrication by hard templating with the use of a masking strategy and surface functionalization methods, is developed to produce arrays of gold nanopillars of spatially-controlled surface chemistry. Therefore, a gold nanopillar array is first fabricated by performing metal electrochemical deposition into a track-etched membrane supported on a gold substrate. After dissolution of the membrane, a protective polymer layer is deposited on the array and partially etched to specifically reveal the top of the nanopillars. Then, a polythiolactone-based copolymer is grafted on the upper part of the nanopillars. Afterwards, the sacrificial polymer layer is dissolved to reveal the non-functionalized surface corresponding to the lower part of the gold nanopillars and the background surface. This surface is subsequently modified by a self-assembled monolayer (SAM) of alkylthiol molecules which leads to nanostructured surfaces with spatio-selective surface chemistry. The grafting of gold nanoparticles and of a bioadhesive peptide on the top and on the background of the nanopillar array, respectively, is performed to prove the versatility of the approach to produce bifunctionalized nanopillar arrays for biological, biosensing or (bio)catalysis applications.

7.
Emerg Infect Dis ; 24(10): 1850-1858, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30226164

RESUMO

Congenital Zika virus syndrome consists of a large spectrum of neurologic abnormalities seen in infants infected with Zika virus in utero. However, little is known about the effects of Zika virus intrauterine infection on the neurocognitive development of children born without birth defects. Using a case-control study design, we investigated the temporal association of a cluster of congenital defects with Zika virus infection. In a nested study, we also assessed the early childhood development of children recruited in the initial study as controls who were born without known birth defects,. We found evidence for an association of congenital defects with both maternal Zika virus seropositivity (time of infection unknown) and symptomatic Zika virus infection during pregnancy. Although the early childhood development assessment found no excess burden of developmental delay associated with maternal Zika virus infection, larger, longer-term studies are needed.


Assuntos
Desenvolvimento Infantil , Exposição Materna/efeitos adversos , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/etiologia , Efeitos Tardios da Exposição Pré-Natal , Infecção por Zika virus/complicações , Infecção por Zika virus/epidemiologia , Zika virus , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/etiologia , Estudos Transversais , Feminino , Geografia Médica , História do Século XXI , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Razão de Chances , Avaliação de Resultados da Assistência ao Paciente , Polinésia/epidemiologia , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/história , Vigilância em Saúde Pública , Adulto Jovem , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/virologia
8.
J Mater Chem B ; 4(47): 7651-7661, 2016 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-32263821

RESUMO

Mats of nanofibers are important as biological scaffolds, (bio)functional electrodes, or smart membranes. Herein, we show that layer-by-layer (LbL) assembly of a wide variety of compounds in nanoporous templates, followed by a straightforward filtration methodology of the nanotubes after membrane dissolution, leads to the fabrication of LbL nanopapers over centimeter square surfaces. The texture of the nanopapers can be easily tuned by varying the rigidity of the nanofibers, which can be achieved by changing their wall thickness, crosslinking them, or developing nanotubes with a core-shell structure. In the nanopapers, the tubes deform by different mechanisms, including flattening, twisting and scrolling, depending on tube rigidity. The possibility to manufacture multilayered nanopapers made of stacks of different nanofibers, or chemically post-functionalize them, is also demonstrated; in addition, the fabrication of enzymatically-active nanopapers is shown. Considering the vast range of materials which can be used for the construction of nanotubes including, e.g., proteins, polysaccharides, conducting polymers or nanoparticles, and the many possible post-functionalization techniques of LbL films, the methodology offers a very flexible route to a virtually limitless collection of functional smart nanopapers.

9.
Biotechnol Bioeng ; 112(10): 1986-96, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26058804

RESUMO

Microbial laccases are powerful enzymes capable of degrading lignin and other recalcitrant compounds including endocrine disrupting chemicals (EDCs). Efficient EDC removal on an industrial scale requires robust, stable, easy to handle and cost-effective immobilized biocatalysts. In this direction, magnetic biocatalysts are attractive due to their easy separation through an external magnetic field. Recently, a bioinspired immobilization technique that mimics the natural biomineralization reactions in diatoms has emerged as a fast and versatile tool for generating robust, cheap, and highly stable (nano) biocatalysts. In this work, bioinspired formation of a biotitania matrix is triggered on the surface of magnetic particles in the presence of laccase in order to produce laccase-biotitania (lac-bioTiO2 ) biocatalysts suitable for environmental applications using a novel, fast and versatile enzyme entrapment technique. Highly active lac-bioTiO2 particles have been produced and the effect of different parameters (enzyme loading, titania precursor concentration, pH, duration of the biotitania formation, and laccase adsorption steps) on the apparent activity yield of these biocatalysts were evaluated, the concentration of the titania precursor being the most influential. The lac-bioTiO2 particles were able to catalyze the removal of bisphenol A, 17α-ethinylestradiol and diclofenac in a mixture of six model EDCs and retained 90% of activity after five reaction cycles and 60% after 10 cycles.


Assuntos
Disruptores Endócrinos/isolamento & purificação , Enzimas Imobilizadas/metabolismo , Lacase/metabolismo , Magnetismo , Titânio/metabolismo , Poluentes da Água/isolamento & purificação , Compostos Benzidrílicos/isolamento & purificação , Diclofenaco/isolamento & purificação , Etinilestradiol/isolamento & purificação , Fenóis/isolamento & purificação , Purificação da Água/métodos
10.
PLoS One ; 9(10): e109320, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25303180

RESUMO

INTRODUCTION: We aimed to study the relationships between educational level, women's knowledge about cervical cancer (CC), and acceptance of HPV vaccination for their daughters. METHODS: We analysed data from a quantitative (self-administrated questionnaire) and qualitative (semi-structured interviews) cross-sectional study performed in 2008 among 1,229 French 18-65-year-old women recruited by general practitioners. Women were categorized into three educational level groups: low (LEL: 43.9%), medium (MEL: 33.4%) and high (HEL: 22.6%). RESULTS: Knowledge about CC and its prevention was lower among LEL women. In the 180 mothers of 14-18-year-old daughters (99 LEL, 54 MEL, 45 HEL), acceptance of HPV vaccine was higher in LEL (60.4%) and MEL (68.6%) than in HEL mothers (46.8%). Among LEL mothers, those who were favourable to HPV vaccination were more likely to be young (OR = 8.44 [2.10-34.00]), to be vaccinated against hepatitis B (OR = 4.59 [1.14-18.52]), to have vaccinated their children against pneumococcus (OR = 3.52 [0.99-12.48]) and to present a history of abnormal Pap smear (OR = 6.71 [0.70-64.01]). CONCLUSION: Although LEL women had poorer knowledge about CC and its prevention, they were more likely to accept HPV vaccination than HEL mothers.


Assuntos
Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/uso terapêutico , Neoplasias do Colo do Útero/prevenção & controle , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Vacinação , Adulto Jovem
11.
Biomacromolecules ; 15(10): 3706-16, 2014 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-25136931

RESUMO

Immobilized proteins or peptides are of critical importance for applications such as biosensing or cell culture. We analyze the structure of layers of a large variety of proteins and peptides, grafted on silicon substrates by different routes differing in the nature of the intermediate layer linking the biomolecules to the substrate, either a silane monolayer, or a polyelectrolyte multilayer made from synthetic or natural polymers. The structural analysis is essentially performed by X-ray reflectometry, which proves to be an efficient methodology not requiring the use of tagged biomolecules, capable of evaluating consistently the amount of grafted biomolecules per surface area with estimated precisions ranging from 10 to 20%. The study provides a quantitative basis for selecting one among a series of well-proofed and sturdy grafting methodologies and underlines the potential of XRR for assessing the amount of grafted biomacromolecules without requiring the expensive tagging of molecules. Our results also show that, for the coupling route resting on synthetic polyelectrolytes, the grafting density is significantly lower than for direct coupling over a silane layer. In contrast, when performed over a cushion based on polysaccharides, the grafting density is well above the values found for a dense layer grafted on a silane monolayer, indicating partial penetration and swelling of the polysaccharide cushion.


Assuntos
Peptídeos/química , Proteínas/química , Silanos/química , Polissacarídeos/química , Silício/química , Propriedades de Superfície
12.
Int J Public Health ; 59(3): 519-28, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24756880

RESUMO

OBJECTIVES: To use both quantitative and qualitative methods to investigate the evolution of practices and opinions regarding human papillomavirus (HPV) vaccination among French general practitioners. METHODS: A cross-sectional study (self-questionnaires) was performed in 2007 and repeated in 2010 among 271 general practitioners. Semi-structured interviews were conducted on 27 voluntary participants by a sociologist and analyzed according to content analysis. RESULTS: Acceptability of HPV vaccination had increased from 2007 to 2010 (79.9 vs. 87.1%, respectively), just as the practice of HPV vaccination among 14-year-old girls (19.0 vs. 49.1%, respectively). Though about 60% reported complications associated with HPV vaccination, irrespective of year, the types of difficulties have varied: difficulties related to "questions asked by patients" had decreased, though concerns about side effects had remained stable. During interviews, difficulties related to "the reason for medical consultation" and "the target age" were often associated with addressing the issue of sexuality, especially when the parents were present. CONCLUSIONS: Although the high level of acceptability of HPV vaccination among general practitioners, which increased from 2007 to 2010, there remain difficulties in addressing this practice.


Assuntos
Atitude do Pessoal de Saúde , Clínicos Gerais/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/administração & dosagem , Fatores Etários , Estudos Transversais , Feminino , Humanos , Vacinas contra Papillomavirus/efeitos adversos , Aceitação pelo Paciente de Cuidados de Saúde , Características de Residência , Fatores Sexuais
13.
Eur J Public Health ; 23(6): 1046-53, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23430762

RESUMO

BACKGROUND: Having been vaccinated against the human papilloma virus (HPV) may affect other behaviours related to sexual health. This study assessed knowledge and behaviour relevant to the prevention of sexually transmitted infections (STIs) among girls/women aged 14-23 years in relation to their HPV vaccination status. METHODS: From November 2008 to February 2009, 328 girls/women from the Rhône-Alpes region were recruited by general practitioners and completed a self-administered questionnaire. RESULTS: In all, 316 of the 328 respondents provided information on their HPV vaccination status: 135 (42.7%) had been vaccinated (51.2% of girls aged 14-16 years, 44% of women aged 17-20 years and 18.9% of 21-23-year-olds). Knowledge about HPV and the Pap smear was poor overall but greater in those who had been vaccinated: vaccinated 14-16-year-olds were significantly more likely to know the aim of the Pap smear than those not vaccinated (72.7% vs. 41.3%, P < 0.001), and vaccinated 21-23-year-olds were more likely to know about the need to continue Pap smear screening, despite vaccination (60.0% vs. 25.6%, P = 0.06). Irrespective of vaccination status, >80% cited condoms as a means of STI prevention and >85% of those who were sexually active used them. No difference was observed between vaccinated and non-vaccinated groups regarding requests for HIV serology, history of abortions or emergency hormonal contraception. CONCLUSION: Knowledge about cervical cancer prevention was better among those who had been vaccinated against HPV than among those who had not. Knowledge and behaviour relevant to STI prevention seemed appropriate whatever the respondents' vaccination status.


Assuntos
Vacinas contra Papillomavirus/uso terapêutico , Infecções Sexualmente Transmissíveis/prevenção & controle , Adolescente , Fatores Etários , Feminino , França/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Teste de Papanicolaou/psicologia , Infecções Sexualmente Transmissíveis/psicologia , Inquéritos e Questionários , Neoplasias do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/psicologia , Esfregaço Vaginal/psicologia , Adulto Jovem
14.
BMC Public Health ; 12: 1034, 2012 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-23186288

RESUMO

BACKGROUND: In France, it is recommended that girls and women aged 14-23 are vaccinated against the human papillomavirus (HPV). However, French women's knowledge of and attitude towards the vaccine has been little studied. METHODS: Thirty-nine general practitioners, representative of those working in the large Rhône-Alpes region, offered a self-administered questionnaire on cervical cancer (CC) prevention to all 18-65 year-old women who came for consultation during June and July 2008. In addition, semi-structured interviews were undertaken with a sample of those who had daughters aged 14-18. RESULTS: Of the 1,478 women who completed the questionnaire, only 16.9% mentioned HPV as the cause of CC, even though 76.2% knew of the vaccine. 210 women had daughters aged 14-18, and 32 were interviewed. Compared with the wider group, more of these women were aware of the HPV vaccine (91.4%). 44.8% knew the target population and 17.1% the recommended ages for vaccination. 54.3% favoured HPV vaccination; 37.2% were undecided and only 0.9% were opposed. The main barrier to acceptance was the recency of the vaccine's introduction and concern about possible side effects (54.9%); 14.1% preferred to rely on their GP's decision. Factors associated with acceptance of the HPV vaccine were having previously vaccinated a child against pneumococcus (OR=3.28 [1.32-8.11]) and knowing the target population for HPV vaccination (OR=2.12 [1.15-3.90]). Knowing the recommended frequency of Papanicolaou smear testing (Pap test) screening was associated with lower acceptance (OR=0.32 [0.13-0.82]). CONCLUSIONS: Few mothers are opposed to HPV vaccination. Factors associated with acceptability were knowledge about the vaccine, acceptance of other vaccines and, unexpectedly, lack of knowledge about the recommended frequency of Pap testing. On multivariate analysis, compliance with recommendations for Pap test screening and socioeconomic factors had no effect on views about HPV vaccination. Given that concern about possible side effects is the major barrier to wider acceptance of the HPV vaccine in France, GPs have a key role in providing information.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Vacinas contra Papillomavirus/uso terapêutico , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Neoplasias do Colo do Útero/prevenção & controle , Mulheres/psicologia , Adolescente , Animais , Feminino , França , Humanos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Pesquisa Qualitativa , Neoplasias do Colo do Útero/diagnóstico
15.
PLoS One ; 7(5): e37889, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22655078

RESUMO

Pneumonic-type lung adenocarcinoma (P-ADC) represents a distinct subset of lung cancer with specific clinical, radiological, and pathological features. Given the weak association with tobacco-smoking and the striking similarities with jaagsiekte sheep retrovirus (JSRV)-induced ovine pulmonary adenocarcinoma, it has been suggested that a zoonotic viral agent infecting pulmonary cells may predispose to P-ADC in humans. Our objective was to explore whether exposure to domestic small ruminants may represent a risk factor for P-ADC. We performed a multicenter case-control study recruiting patients with P-ADC as cases and patients with non-P-ADC non-small cell lung cancer as controls. A dedicated 356-item questionnaire was built to evaluate exposure to livestock. A total of 44 cases and 132 controls were included. At multivariate analysis, P-ADC was significantly more associated with female gender (Odds-ratio (OR) = 3.23, 95% confidence interval (CI): 1.32-7.87, p = 0.010), never-smoker status (OR = 3.57, 95% CI: 1.27-10.00, p = 0.015), personal history of extra-thoracic cancer before P-ADC diagnosis (OR = 3.43, 95% CI: 1.10-10.72, p = 0.034), and professional exposure to goats (OR = 5.09, 95% CI: 1.05-24.69, p = 0.043), as compared to other subtypes of lung cancer. This case-control suggests a link between professional exposure to goats and P-ADC, and prompts for further epidemiological evaluation of potential environmental risk factors for P-ADC.


Assuntos
Adenocarcinoma/etiologia , Exposição Ambiental/efeitos adversos , Cabras , Gado , Neoplasias Pulmonares/etiologia , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Adolescente , Adulto , Animais , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Cabras/fisiologia , Humanos , Lactente , Gado/fisiologia , Pulmão/patologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
16.
Biosens Bioelectron ; 26(10): 4139-45, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21536421

RESUMO

A potentiometric biosensor based on urease was developed for the quantitative determination of urea concentration in aqueous solutions for biomedical applications. The urease was either physisorbed onto an electrodeposited polyaniline film (PANI), or immobilized on a layer-by-layer film (LbL) assembled over the PANI film, that was obtained by the alternate deposition of charged polysaccharides (carboxymethylpullulan (CMP) and chitosan (CHI)). In the latter case, the urease (Urs) enzyme was either physically adsorbed or covalently grafted to the LbL film using carbodiimide coupling reaction. Potentiometric responses of the enzymatic biosensors were measured as a function of the urea concentration in aqueous solutions (from 10(-6) to 10(-1) mol L(-1) urea). Very high sensitivity and short response time were observed for the present biosensor. Moreover, a stability study showed a higher stability over time for the potentiometric response of the sensor with the enzyme-grafted LbL film, testifying for the protective nature of the polysaccharide coating and the interest of covalent grafting.


Assuntos
Técnicas Biossensoriais/métodos , Ureia/análise , Compostos de Anilina , Biopolímeros , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/estatística & dados numéricos , Quitosana , Técnicas Eletroquímicas , Estabilidade Enzimática , Enzimas Imobilizadas , Glucanos , Humanos , Potenciometria , Sensibilidade e Especificidade , Ureia/urina , Urease
17.
J Mater Sci Mater Med ; 21(3): 925-30, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20143134

RESUMO

One of the key challenges to engineering neural interfaces is to reduce their immune response toward implanted electrodes. One potential approach to minimize or eliminate this undesired early inflammatory tissue reaction and to maintain signal transmission quality over time is the delivery of anti-inflammatory biomolecules in the vicinity of the implant. Here, we report on a facile and reproducible method for the fabrication of high surface area nanostructured electrodes coated with an electroactive polymer, polypyrrole (PPy) that can be used to precisely release drug by applying an electrical stimuli. The method consists of the electropolymerization of PPy incorporated with drug, dexamethasone (DEX), onto a brush of metallic nanopillars, obtained by electrodeposition of the metal within the nanopores of gold-coated polycarbonate template. The study of the release of DEX triggered by electrochemical stimuli indicates that the system is a true electrically controlled release system. Moreover, it appears that the presence of metallic nanowires onto the electrode surface improves the adherence between the polymer and the electrode and increases the electroactivity of the PPy coating.


Assuntos
Materiais Biocompatíveis/química , Dexametasona/química , Sistemas de Liberação de Medicamentos , Nanotecnologia/métodos , Polímeros/química , Pirróis/química , Anti-Inflamatórios/farmacologia , Eletroquímica/métodos , Eletrodos , Humanos , Metais/química , Microscopia Eletrônica de Varredura/métodos , Nanoestruturas , Platina/química , Próteses e Implantes
18.
BMC Genet ; 9: 83, 2008 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-19061508

RESUMO

BACKGROUND: The Nonsense-Mediated mRNA Decay (NMD) pathway detects and degrades mRNAs containing premature termination codons, thereby preventing the accumulation of potentially detrimental truncated proteins. Intertissue variation in the efficiency of this mechanism has been suggested, which could have important implications for the understanding of genotype-phenotype correlations in various genetic disorders. However, compelling evidence in favour of this hypothesis is lacking. Here, we have explored this question by measuring the ratio of mutant versus wild-type Men1 transcripts in thirteen tissues from mice carrying a heterozygous truncating mutation in the ubiquitously expressed Men1 gene. RESULTS: Significant differences were found between two groups of tissues. The first group, which includes testis, ovary, brain and heart, displays a strong decrease of the nonsense transcript (average ratio of 18% of mutant versus wild-type Men1 transcripts, identical to the value measured in murine embryonic fibroblasts). The second group, comprising lung, intestine and thymus, shows much less pronounced NMD (average ratio of 35%). Importantly, the extent of degradation by NMD does not correlate with the expression level of eleven genes encoding proteins involved in NMD or with the expression level of the Men1 gene. CONCLUSION: Mouse models are an attractive option to evaluate the efficiency of NMD in multiple mammalian tissues and organs, given that it is much easier to obtain these from a mouse than from a single individual carrying a germline truncating mutation. In this study, we have uncovered in the thirteen different murine tissues that we examined up to a two-fold difference in NMD efficiency.


Assuntos
Códon sem Sentido/genética , Especificidade de Órgãos/genética , Estabilidade de RNA/genética , Animais , Regulação da Expressão Gênica , Camundongos , Modelos Animais , Modelos Genéticos , Mutação/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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