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1.
Environ Sci Pollut Res Int ; 30(12): 34243-34254, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36508092

RESUMO

The increasing consumption of cleaning products deteriorates water resources due to harmful components such as phosphorus (P) and nitrogen (N) compounds, oils, bleach, and acids, typical compounds in traditional detergents. The use of biodegradable detergents as an environmentally friendly alternative has been proposed in different regions. In Colombia, resolution 1770/2018 sets a minimum biodegradability rate of 60% for the surfactants present in liquid detergents, which would reduce to a similar extent the impacts on water after their use. However, the environmental impacts of the supply chain of these detergents and their raw materials have not been evaluated so far. This study presents an environmental life cycle assessment of petroleum-based liquid detergents and a comparison to traditional solid detergents, based on the ISO 14040 standard and the ReCiPe-2016 impacts assessment method. A novel bio-detergent containing anionic plant-based surfactants was proposed in this analysis. The impacts of packaging and the distribution of the product to consumers were also considered. Raw materials contributed to 91% of the total of 314 g of CO2 eq generated per liter of liquid detergent, where the production of fatty alcohol sulfate and PET packaging shared 78.8% and 12.2% of the total impact, respectively. It was also determined that 5.4 L of water are consumed and 0.09 g of P eq and 0.1 g of N eq are emitted per liter of detergent. This liquid detergent presented better environmental performance than traditional detergents in all the impact categories, except for the fossil resource scarcity category. The evaluated detergent would significantly mitigate the generation of negative effects on ecosystems. Moreover, the substitution of PET for HDPE packaging could reduce the impacts on freshwater eutrophication by 10%, although the carbon footprint can slightly increase, which could be compensated due to its higher recyclability rate. In contrast, the proposed bio-detergent would not have significant benefits and would negatively affect water consumption and land use in its supply chain.


Assuntos
Detergentes , Meio Ambiente , Tensoativos/química , Detergentes/química , Colômbia , Plantas/química , Petróleo , Fatores de Tempo , Embalagem de Produtos
2.
Curr Protoc ; 2(6): e452, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35714356

RESUMO

Understanding the mechanisms of membrane protein function is critical for biomedical research and drug discovery as membrane proteins constitute ∼30% of the proteins encoded by the genomes of both lower and higher organisms and are targets for two-thirds of approved drugs worldwide. Significant progress has been made in engineering host expression systems for large-scale production of membrane proteins and in determining their three-dimensional high-resolution structures. Despite these efforts, the study of membrane proteins at the atomic level is challenging due to poor expression and extraction, low yields of functional protein, and the complexity and heterogeneity of source membranes. Structural and spectroscopic studies of any membrane protein require that the protein be extracted from its native membranes into a membrane-mimetic stable environment, which is often achieved by the use of detergents. Unfortunately, there is no magic detergent that can extract all membrane proteins and successful extraction often requires a thorough screen of detergents. Furthermore, membrane protein purification in general and the detergents used are very expensive, which puts a financial constraint on sophisticated membrane protein studies. To overcome this hurdle, a dual-detergent strategy has recently been developed and successfully applied to purify various classes of pure, stable, and functionally relevant membrane proteins in a cost-effective manner. This strategy uses an inexpensive detergent for solubilization of the desired protein from membranes and a second detergent during protein purification. In the Basic Protocol, we describe the dual-detergent strategy to significantly reduce the overall purification cost of a bacterial membrane protein using the magnesium ion channel MgtE as an example. Support Protocols are also provided for selecting a suitable E. coli strain for protein expression and the optimal detergent(s) for membrane protein solubilization. © 2022 Wiley Periodicals LLC. Basic Protocol: Expression, membrane solubilization, and cost-effective purification of MgtE Support Protocol 1: Selecting a suitable E. coli strain for optimal protein expression Support Protocol 2: Identification of suitable detergents for membrane protein solubilization.


Assuntos
Detergentes , Proteínas de Membrana , Proteínas de Bactérias/química , Análise Custo-Benefício , Detergentes/química , Escherichia coli/genética , Proteínas de Membrana/genética
3.
N Biotechnol ; 61: 90-98, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33279718

RESUMO

We have recently described a non-chromatographic, ligand-free approach for antibody (Ab) purification based on specially designed [Tween-20:bathophenanthroline:Fe2+] aggregates. To assess the potential generality of this approach, a variety of detergents belonging to four nonionic detergent families (Tween, Brij, Triton and Pluronic) have now been studied. All surfactant aggregates led to high purity of the recovered Ab's (>95 %, by gel densitometry). Good overall Ab recovery yields were observed with Tween-20 (80-83 %), Brij-O20 (85-87 %) and Triton X-100 (87-90 %), while Pluronic F-127 was less efficient (42-53 %). Of additional importance is the finding that the process was performed by filtration rather than centrifugation, thereby allowing a continuous purification mode that led to the recovery of monomeric IgG, as determined by dynamic light scattering and preservation of Ab specificity as measured by ELISA. The amphiphilic chelator, bathophenanthroline (batho) was recycled almost quantitatively (95 %) by crystallization. Good IgG recovery yields of ∼80 % were also observed when Ab concentrations were increased from 1 mg/mL to 3-5 mg/mL. Potential advantages of the purification platform for industrial downstream processing of therapeutic monoclonal antibodies, are discussed.


Assuntos
Anticorpos/isolamento & purificação , Detergentes/química , Proteína Estafilocócica A/química , Anticorpos/química , Cromatografia , Compostos Ferrosos/química , Ligantes , Micelas , Estrutura Molecular , Fenantrolinas/química , Polissorbatos/química
4.
Dermatitis ; 30(6): 358-362, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31724989

RESUMO

BACKGROUND: Surfactants are common ingredients in topical products, which can cause both irritant and allergic contact dermatitis. OBJECTIVE: The aim of this study was to determine the prevalence of 12 common groups of surfactants and 12 common individual surfactants among products in each category in the American Contact Dermatitis Society Contact Allergen Management Program (CAMP). METHODS: The American Contact Dermatitis Society CAMP was queried for the 12 surfactant groups and the 12 individual surfactants. RESULTS: The laureth/pareth sulfate group was the most prevalent surfactant group in CAMP products (17.9%). Laureth/pareth sulfates were the most common surfactant group in all product categories, except household and eye care products. The betaine/sultaine group (13.5%) and glucosides (10.0%) were also found in a significant proportion of CAMP products. Oleamidopropyl dimethylamine has the highest positive reaction rate (3.5%) but was tied for the lowest prevalence (0.20%) of the 12 individual surfactants studied. In contrast, cocamidopropyl betaine has a lower positive reaction rate (1.6%) with a higher prevalence (10.4%). CONCLUSIONS: Surfactants were commonly found across all product types in CAMP. This study provides important information on allergen and irritant exposures in care products.


Assuntos
Cosméticos/química , Dermatite Alérgica de Contato/etiologia , Produtos Domésticos , Tensoativos/efeitos adversos , Compostos de Benzalcônio/efeitos adversos , Betaína/efeitos adversos , Betaína/análogos & derivados , Bases de Dados de Compostos Químicos , Detergentes/química , Etanolaminas/efeitos adversos , Glucosídeos/efeitos adversos , Tinturas para Cabelo/química , Preparações para Cabelo/química , Humanos , Propilaminas/efeitos adversos , Sabões/química , Dodecilsulfato de Sódio/efeitos adversos
5.
Protein Expr Purif ; 161: 8-16, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31028884

RESUMO

Although magnesium is the second most abundant cation present in the cell, the transport mechanism of Mg2+ across membranes is poorly understood. Importantly, the prokaryotic MgtE Mg2+ channel is related to mammalian SLC41A1 transporters and, therefore, biochemical and biophysical characterization of MgtE and its orthologs assumes significance. To date, the purification and structure determination of MgtE from Thermus thermophilus has been carried out using the widely used nonionic detergent, n-dodecyl-ß-d-maltopyranoside (DDM). However, DDM is an expensive detergent and alternative methods to produce high-quality proteins in stable and functional form will be practically advantageous to carry out structural studies in a cost-effective manner. In this work, we have utilized 'dual-detergent strategy' to successfully purify MgtE channel in a stable and functional form by employing relatively inexpensive detergents (Triton X-100 and Anzergent 3-14) for membrane solubilization and subsequently changed to DDM during purification. Our results show that Triton X-100 and Anzergent 3-14 extract MgtE well and the quality of purified protein is comparable to DDM-extracted MgtE. Interestingly, addition of high concentration of salt and glycerol during solubilization does not significantly affect the quantity and quality of MgtE. Importantly, limited proteolysis assay, circular dichroism spectroscopy and ensemble tryptophan fluorescence strongly support the use of Triton X-100, in particular, as an inexpensive, alternative detergent for the purification of MgtE without compromising the structural integrity of the channel and Mg2+-induced gating-related conformational dynamics. Overall, these results are relevant for the cost-effective purification of stable and functional membrane proteins in general, and magnesium channels, in particular.


Assuntos
Antiporters/química , Antiporters/isolamento & purificação , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Fracionamento Químico/métodos , Cromatografia em Gel/métodos , Thermus thermophilus/química , Thermus thermophilus/metabolismo , Antiporters/genética , Antiporters/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Fracionamento Químico/instrumentação , Cromatografia em Gel/economia , Cromatografia em Gel/instrumentação , Detergentes/química , Magnésio/metabolismo , Modelos Moleculares , Thermus thermophilus/genética
6.
Proteomics ; 18(17): e1800220, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30035338

RESUMO

A major challenge in the field of proteomics is obtaining high-quality peptides for comprehensive proteome profiling by LC-MS. Here, evaluation and modification of a range of sample preparation methods using photosynthetically active Arabidopsis leaf tissue are done. It was found that inclusion of filter-aided sample preparation (FASP) based on filter digestion improves all protein extraction methods tested. Ultimately, a detergent-free urea-FASP approach that enables deep and robust quantification of leaf and root proteomes is shown. For example, from 4-day-old leaf tissue, up to 11 690 proteins were profiled from a single sample replicate. This method should be broadly applicable to researchers working with difficult to process plant samples.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Proteoma/metabolismo , Manejo de Espécimes/métodos , Arabidopsis/crescimento & desenvolvimento , Detergentes/química , Filtração , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/crescimento & desenvolvimento , Proteoma/análise
7.
Chem Rev ; 118(7): 3559-3607, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29488756

RESUMO

Membrane proteins perform a host of vital cellular functions. Deciphering the molecular mechanisms whereby they fulfill these functions requires detailed biophysical and structural investigations. Detergents have proven pivotal to extract the protein from its native surroundings. Yet, they provide a milieu that departs significantly from that of the biological membrane, to the extent that the structure, the dynamics, and the interactions of membrane proteins in detergents may considerably vary, as compared to the native environment. Understanding the impact of detergents on membrane proteins is, therefore, crucial to assess the biological relevance of results obtained in detergents. Here, we review the strengths and weaknesses of alkyl phosphocholines (or foscholines), the most widely used detergent in solution-NMR studies of membrane proteins. While this class of detergents is often successful for membrane protein solubilization, a growing list of examples points to destabilizing and denaturing properties, in particular for α-helical membrane proteins. Our comprehensive analysis stresses the importance of stringent controls when working with this class of detergents and when analyzing the structure and dynamics of membrane proteins in alkyl phosphocholine detergents.


Assuntos
Membrana Celular/ultraestrutura , Detergentes/química , Proteínas de Membrana/química , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Animais , Fenômenos Biofísicos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Espectroscopia de Ressonância Magnética/métodos , Micelas , Modelos Moleculares , Conformação Proteica , Dobramento de Proteína , Estabilidade Proteica , Solubilidade
8.
Food Chem Toxicol ; 116(Pt A): 42-52, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29175187

RESUMO

Non-pathogenic Bacillus species used in cleaning products produce the appropriate enzymes to degrade stains and soils. However, there is little scientific data regarding the human exposure by inhalation of Bacillus spores during or after use of microbial-based cleaning products. Herein, air samples were collected at various locations in a ventilated, carpeted, residential room to determine the air concentration of viable bacteria and spores during and after the application of microbial-based carpet cleaning products containing Bacillus spores. The influence of human activities and vacuuming was investigated. Bioaerosol levels associated with use and post-application activities of whole room carpet treatments were elevated during post-application activity, but quickly returned to the indoor background range. Use of trigger spray spot applications generated aerosolized spores in the immediate vicinity, however, their use pattern and the generation of mostly non-respirable particles suggest minimal risks for pulmonary exposure from their use. The aerosol counts associated with use of these microbial-based cleaners were below the recommendation for safe exposure levels to non-pathogenic and non-toxigenic microorganisms except during application of the spot cleaner. The data presented suggest that carpet cleaning products, containing non-pathogenic Bacillus spores present a low potential for inhalation exposure and consequently minimal risk of adverse effects.


Assuntos
Bacillus/química , Fatores Biológicos/efeitos adversos , Detergentes/efeitos adversos , Exposição por Inalação/efeitos adversos , Aerossóis/análise , Fatores Biológicos/química , Qualidade de Produtos para o Consumidor , Detergentes/química , Pisos e Cobertura de Pisos , Humanos , Exposição por Inalação/análise , Esporos Bacterianos/química
9.
J Pharm Biomed Anal ; 149: 33-39, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29100028

RESUMO

A Total Organic Carbon (TOC) based analytical method to quantitate trace residues of clean-in-place (CIP) detergents CIP100® and CIP200® on the surfaces of pharmaceutical manufacturing equipment was developed and validated. Five factors affecting the development and validation of the method were identified: diluent composition, diluent volume, extraction method, location for TOC sample preparation, and oxidant flow rate. Key experimental parameters were optimized to minimize contamination and to improve the sensitivity, recovery, and reliability of the method. The optimized concentration of the phosphoric acid in the swabbing solution was 0.05M, and the optimal volume of the sample solution was 30mL. The swab extraction method was 1min sonication. The use of a clean room, as compared to an isolated lab environment, was not required for method validation. The method was demonstrated to be linear with a correlation coefficient (R) of 0.9999. The average recoveries from stainless steel surfaces at multiple spike levels were >90%. The repeatability and intermediate precision results were ≤5% across the 2.2-6.6ppm range (50-150% of the target maximum carry over, MACO, limit). The method was also shown to be sensitive with a detection limit (DL) of 38ppb and a quantitation limit (QL) of 114ppb. The method validation demonstrated that the developed method is suitable for its intended use. The methodology developed in this study is generally applicable to the cleaning verification of any organic detergents used for the cleaning of pharmaceutical manufacturing equipment made of electropolished stainless steel material.


Assuntos
Carbono/análise , Detergentes/química , Contaminação de Medicamentos/prevenção & controle , Contaminação de Equipamentos/prevenção & controle , Tecnologia Farmacêutica/métodos , Limite de Detecção , Oxirredução , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sonicação , Aço Inoxidável/química , Tecnologia Farmacêutica/normas
10.
J Cardiovasc Transl Res ; 10(2): 93-103, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28281241

RESUMO

Cryopreserved allogeneic conduits are the elective biocompatible choice among currently available substitutes for surgical replacement in end-stage valvulopathy. However, degeneration occurs in 15 years in adults or faster in children, due to recipient's immunological reactions to donor's antigens. Here, human aortic valves were decellularized by TRICOL, based on Triton X-100 and sodium cholate, and submitted to standard cryopreservation (TRICOL-human aortic valves (hAVs)). Tissue samples were analyzed to study the effects of the combined procedure on original valve architecture and donor's cell removal. Residual amounts of nucleic acids, pathological microorganisms, and detergents were also investigated. TRICOL-hAVs proved to be efficaciously decellularized with removal of donor's cell components and preservation of valve scaffolding. Trivial traces of detergents, no cytotoxicity, and abrogated bioburden were documented. TRICOL-hAVs may represent off-the-shelf alternatives for both aortic and pulmonary valve replacements in pediatric and grown-up with congenital heart disease patients.


Assuntos
Valva Aórtica/transplante , Bioprótese , Criopreservação , Implante de Prótese de Valva Cardíaca/instrumentação , Próteses Valvulares Cardíacas , Desenho de Prótese , Adolescente , Adulto , Aloenxertos , Valva Aórtica/citologia , Detergentes/química , Estudos de Viabilidade , Feminino , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Masculino , Teste de Materiais , Pessoa de Meia-Idade , Octoxinol/química , Colato de Sódio/química , Sobrevivência de Tecidos , Transplante Homólogo
11.
Acta Biomater ; 53: 268-278, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28161576

RESUMO

Decellularized extracellular matrix (ECM) derived from tissues and organs are emerging as important scaffold materials for regenerative medicine. Many believe that preservation of the native ECM structure during decellularization is highly desirable. However, because effective techniques to assess the structural damage in ECM are lacking, the disruptive effects of a decellularization method and the impact of the associated structural damage upon the scaffold's regenerative capacity are often debated. Using a novel collagen hybridizing peptide (CHP) that specifically binds to unfolded collagen chains, we investigated the molecular denaturation of collagen in the ECM decellularized by four commonly used cell-removing detergents: sodium dodecyl sulfate (SDS), 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS), sodium deoxycholate (SD), and Triton X-100. Staining of the detergent-treated porcine ligament and urinary bladder matrix with carboxyfluorescein-labeled CHP demonstrated that SDS and Triton X-100 denature the triple helical collagen molecule while CHAPS and SD do not, although second harmonic generation imaging and transmission electron microscopy (TEM) revealed that all four detergents disrupt collagen fibrils. Our findings from the CHP staining were further confirmed by the circular dichroism spectra of intact triple helical collagen molecules in CHAPS and SD solutions, and the TEM images of CHP-conjugated gold nanoparticles binding only to the SDS and Triton X-100 treated collagen fibrils. CHP is a powerful new tool for direct and reliable measurement of denatured collagen molecules in decellularized tissues. It is expected to have wide applications in the development and standardization of the tissue/organ decellularization technology. STATEMENT OF SIGNIFICANCE: Preservation of the native ECM structure in decellularized tissues is highly desirable, since denaturation of ECM molecules (e.g., collagen) during decellularization can strongly influence the cellular response. Unfortunately, conventional techniques (SEM, SHG) are not conducive to identifying denatured collagen molecules in tissues. We demonstrate the first investigation into the molecular denaturation of collagen in decellularized ECM enabled by a novel Collagen Hybridizing Peptide (CHP) that specifically binds to unfolded collagen chains. We show that SDS and Triton X-100 denature collagen molecules while CHAPS and SD cannot. Such detection has been nearly impossible with other existing techniques. The CHP technique will advance our understanding about the effect of the cell-removing process on ECM, and lead to development of the decellularization technology.


Assuntos
Fracionamento Celular/métodos , Sistema Livre de Células/química , Colágeno/química , Detergentes/química , Matriz Extracelular/química , Peptídeos/química , Animais , Células Cultivadas , Colágeno/ultraestrutura , Microscopia/métodos , Desnaturação Proteica , Coloração e Rotulagem , Suínos , Bexiga Urinária/anatomia & histologia , Bexiga Urinária/química
12.
Int J Mol Sci ; 17(8)2016 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-27517919

RESUMO

Silk fibers suffer from microstructural changes due to various external environmental conditions including daily washings. In this paper, we take the backscattering Mueller matrix images of silk samples for non-destructive and real-time quantitative characterization of the wavelength-scale microstructure and examination of the effects of washing by different detergents. The 2D images of the 16 Mueller matrix elements are reduced to the frequency distribution histograms (FDHs) whose central moments reveal the dominant structural features of the silk fibers. A group of new parameters are also proposed to characterize the wavelength-scale microstructural changes of the silk samples during the washing processes. Monte Carlo (MC) simulations are carried out to better understand how the Mueller matrix parameters are related to the wavelength-scale microstructure of silk fibers. The good agreement between experiments and simulations indicates that the Mueller matrix polarimetry and FDH based parameters can be used to quantitatively detect the wavelength-scale microstructural features of silk fibers. Mueller matrix polarimetry may be used as a powerful tool for non-destructive and in situ characterization of the wavelength-scale microstructures of silk based materials.


Assuntos
Detergentes/química , Seda/química , Método de Monte Carlo
13.
J. pediatr. (Rio J.) ; 92(3): 290-295, tab, graf
Artigo em Inglês | LILACS | ID: lil-785073

RESUMO

Abstract Objective: To evaluate the pH value of children's antibacterial soaps and syndets used in children's baths and verify whether there is information regarding pH on the product label. Methods: Quantitative, cross-sectional, analytical observational study that included ninety soap samples, both in bar and liquid presentations, as follows: 67 children's soap (group 1), 17 antibacterial soaps (group 2), and 6 syndets (group 3). Each sample had its pH measured after 1% dilution. In addition to descriptive statistics, the Pearson-Yates chi-squared test and Student's t-tests were applied, considering the minimal significance level of 5%. The Wilcoxon-Mann-Whitney test, Fisher's exact test, and the Kruskal-Wallis test were used for inferential statistics. Results: The pH levels varied considerably between liquid and bar presentations, with lower levels (4.4-7.9) found for the liquids (p < 0.05). Syndets showed pH levels close to the ideal (slightly acid) and the antibacterial soaps showed the highest pH levels (up to 11.34) (p < 0.05). Only two of the soaps included in the study had information about their pH levels on the product packaging. Conclusions: Knowledge of the pH of children's soap by doctors and users is important, considering the great pH variability found in this study. Moreover, liquid soaps, and especially syndets, are the most recommended for the sensitive skin of neonates and infants, in order to guarantee skin barrier efficacy.


Resumo Objetivos: Avaliar o pH dos sabonetes infantis, antibacterianos e sindets (syntetic detergents) habitualmente usados em crianças, bem como verificar se há no rótulo desses produtos informação sobre seu pH. Métodos: Estudo observacional, analítico, transversal e quantitativo, que incluiu 90 sabonetes nas apresentações em barra e líquida, 67 infantis (grupo 1), 17 antibacterianos (grupo 2) e 6 sindets (grupo 3). Procedeu-se à mensuração do pH das amostras após diluição a 1%. Além da estatística descritiva, foram usados os testes de qui-quadrado Persons/Yates e t de Student, com nível de significância mínimo de 5%. Para a estatística inferencial, foram usados os testes de Wilcoxon-Mann-Whitney, exato de Fisher e Kruskal-Wallis. Resultados: O pH variou consideravelmente entre as formas líquida e em barra, com pHs menores (de 4,4 a 7,9) nos líquidos (p < 0,05). Os sindets mostraram pHs próximos ao ideal (levemente ácidos) e os antibacterianos apresentaram os maiores pHs (até 11,34) (p < 0.05). Apenas dois dos sabonetes analisados apresentavam no rótulo a indicação do pH. Conclusões: A observação do pH dos sabonetes infantis pelos médicos e usuários é importante, haja vista a grande variabilidade de valores de pH encontrados. Além disso, os sabonetes líquidos, e especialmente os sindets, são os mais recomendados para uso em recém-nascidos e lactentes com pele sensível, de forma a garantir a eficácia da barreira cutânea.


Assuntos
Humanos , Recém-Nascido , Lactente , Sabões/química , Detergentes/química , Concentração de Íons de Hidrogênio , Antibacterianos/química , Sabões/classificação , Brasil , Estudos Transversais , Detergentes/classificação
14.
J Pediatr (Rio J) ; 92(3): 290-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26844391

RESUMO

OBJECTIVE: To evaluate the pH value of children's antibacterial soaps and syndets used in children's baths and verify whether there is information regarding pH on the product label. METHODS: Quantitative, cross-sectional, analytical observational study that included ninety soap samples, both in bar and liquid presentations, as follows: 67 children's soap (group 1), 17 antibacterial soaps (group 2), and 6 syndets (group 3). Each sample had its pH measured after 1% dilution. In addition to descriptive statistics, the Pearson-Yates chi-squared test and Student's t-tests were applied, considering the minimal significance level of 5%. The Wilcoxon-Mann-Whitney test, Fisher's exact test, and the Kruskal-Wallis test were used for inferential statistics. RESULTS: The pH levels varied considerably between liquid and bar presentations, with lower levels (4.4-7.9) found for the liquids (p<0.05). Syndets showed pH levels close to the ideal (slightly acid) and the antibacterial soaps showed the highest pH levels (up to 11.34) (p<0.05). Only two of the soaps included in the study had information about their pH levels on the product packaging. CONCLUSIONS: Knowledge of the pH of children's soap by doctors and users is important, considering the great pH variability found in this study. Moreover, liquid soaps, and especially syndets, are the most recommended for the sensitive skin of neonates and infants, in order to guarantee skin barrier efficacy.


Assuntos
Antibacterianos/química , Detergentes/química , Concentração de Íons de Hidrogênio , Sabões/química , Brasil , Estudos Transversais , Detergentes/classificação , Humanos , Lactente , Recém-Nascido , Sabões/classificação
15.
Biochim Biophys Acta ; 1858(1): 47-56, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26454038

RESUMO

In our previous study we examined the functionality and stability of nicotinic acetylcholine receptor (nAChR)-detergent complexes (nAChR-DCs) from affinity-purified Torpedo californica (Tc) using fluorescence recovery after photobleaching (FRAP) in Lipidic Cubic Phase (LCP) and planar lipid bilayer (PLB) recordings for phospholipid and cholesterol like detergents. In the present study we enhanced the functional characterization of nAChR-DCs by recording macroscopic ion channel currents in Xenopus oocytes using the two electrode voltage clamp (TEVC). The use of TEVC allows for the recording of macroscopic currents elicited by agonist activation of nAChR-DCs that assemble in the oocyte plasma membrane. Furthermore, we examined the stability of nAChR-DCs, which is obligatory for the nAChR crystallization, using a 30 day FRAP assay in LCP for each detergent. The present results indicate a marked difference in the fractional fluorescence recovery (ΔFFR) within the same detergent family during the 30 day period assayed. Within the cholesterol analog family, sodium cholate and CHAPSO displayed a minimum ΔFFR and a mobile fraction (MF) over 80%. In contrast, CHAPS and BigCHAP showed a marked decay in both the mobile fraction and diffusion coefficient. nAChR-DCs containing phospholipid analog detergents with an alkylphosphocholine (FC) and lysofoscholine (LFC) of 16 carbon chains (FC-16, LFC-16) were more effective in maintaining a mobile fraction of over 80% compared to their counterparts with shorter acyl chain (C12, C14). The significant differences in macroscopic current amplitudes, activation and desensitization rates among the different nAChR-DCs evaluated in the present study allow to dissect which detergent preserves both, agonist activation and ion channel function. Functionality assays using TEVC demonstrated that LFC16, LFC14, and cholate were the most effective detergents in preserving macroscopic ion channel function, however, the nAChR-cholate complex display a significant delay in the ACh-induce channel activation. In summary, these results suggest that the physical properties of the lipid analog detergents (headgroup and acyl chain length) are the most effective in maintaining both the stability and functionality of the nAChR in the detergent solubilized complex.


Assuntos
Detergentes/química , Bicamadas Lipídicas/química , Oócitos/fisiologia , Fosfolipídeos/química , Receptores Nicotínicos/química , Torpedo/metabolismo , Animais , Membrana Celular/química , Membrana Celular/fisiologia , Colesterol/química , Ácidos Cólicos/química , Cristalização , Detergentes/classificação , Potenciais Evocados/fisiologia , Recuperação de Fluorescência Após Fotodegradação , Microinjeções , Oócitos/química , Técnicas de Patch-Clamp , Ligação Proteica , Estabilidade Proteica , Receptores Nicotínicos/isolamento & purificação , Receptores Nicotínicos/fisiologia , Colato de Sódio/química , Relação Estrutura-Atividade , Termodinâmica , Xenopus laevis/metabolismo
16.
Protein Expr Purif ; 116: 30-41, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26276474

RESUMO

The novel bacterium, Rhodococcus sp. PKPD-CL was isolated and identified from the 'Chilika Lake' located at Odisha state of India, which is a largest brackish water habitat in Asia. Rhodococcus sp. PKPD-CL produces extracellular halo tolerant, detergent and organic solvent stable alkaline cholesterol oxidase. It has apparent molecular weight of 60 kDa and was purified 59 fold by using 60% saturated ammonium sulfate fractionation, anion exchange followed by size exclusion chromatographic techniques with 37% recovery. It showed substrate specificity for 3ß-hydroxysteroids with Km of 1.1 × 10(-4)M for cholesterol. The pH, 8.0 and the temperature, 37 °C were required for its optimum activity. Enzyme is considerably stable at pH 6.0-8.5 and temperature up to 50 °C. At 4 and 30 °C it maintained its 100% activity up to 60 days. The isoelectric point of the enzyme was 9.5. It showed 80% residual activity with 20% NaCl (3.42 M) and 83% relative activity with 12% NaCl (2.05 M) concentration. The metal ions like Zn(2+), Cu(2+), Ag+, Fe(3+), Ba(2+) inhibited the enzyme activity >60% while Hg(2+) served a potent inhibitor whereas Mg(2+) found to be a good enhancer for it. The enzyme was stable in presence of chemical reagents (NaN3, EDTA), detergents (Tween-80, Tween-20, Triton X-100, sodium cholate) and various organic solvents (isopropanol, ethanol, benzene, chloroform, methanol, toluene, ethyl acetate, butanol and dimethylsulfoxide). Such a multi stress tolerant and versatile enzyme produced by Rhodococcus sp. PKPD-CL may serve as a good choice for industrial applications.


Assuntos
Colesterol Oxidase/química , Colesterol Oxidase/metabolismo , Rhodococcus/enzimologia , Colesterol Oxidase/isolamento & purificação , Cromatografia em Gel , Cromatografia por Troca Iônica , Detergentes/química , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Rhodococcus/química , Rhodococcus/crescimento & desenvolvimento , Salinidade , Solventes/química , Especificidade por Substrato
17.
Food Chem Toxicol ; 84: 8-17, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26206496

RESUMO

Ceramide 3 is used mainly as a moisturizer in various cosmetic products. Although several safety studies on formulations containing pseudo-ceramide or ceramide have been conducted at the preclinical and clinical levels for regulatory approval, no studies have evaluated the systemic toxicity of ceramide 3. To address this issue, we conducted a risk assessment and comprehensive toxicological review of ceramide and pseudo-ceramide. We assumed that ceramide 3 is present in various personal and cosmetic products at concentrations of 0.5-10%. Based on previously reported exposure data, the margin of safety (MOS) was calculated for product type, use pattern, and ceramide 3 concentration. Lipsticks with up to 10% ceramide 3 (MOS = 4111) are considered safe, while shampoos containing 0.5% ceramide 3 (MOS = 148) are known to be safe. Reported MOS values for body lotion applied to the hands (1% ceramide 3) and back (5% ceramide 3) were 103 and 168, respectively. We anticipate that face cream would be safe up to a ceramide 3 concentration of 3% (MOS = 149). Collectively, the MOS approach indicated no safety concerns for cosmetic products containing less than 1% ceramide 3.


Assuntos
Cosméticos/toxicidade , Glicoesfingolipídeos/toxicidade , Animais , Fenômenos Químicos , Cosmecêuticos/química , Cosmecêuticos/normas , Cosmecêuticos/toxicidade , Cosméticos/química , Cosméticos/normas , Detergentes/química , Detergentes/toxicidade , Glicoesfingolipídeos/química , Preparações para Cabelo/química , Preparações para Cabelo/normas , Preparações para Cabelo/toxicidade , Humanos , Medição de Risco , Creme para a Pele/química , Creme para a Pele/normas , Creme para a Pele/toxicidade , Toxicocinética
18.
PLoS One ; 10(6): e0131624, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26111144

RESUMO

The great potential of lipases is known since 1930 when the work of J. B. S. Haldane was published. After eighty-five years of studies and developments, are lipases still important biocatalysts? For answering this question the present work investigated the technological development of four important industrial sectors where lipases are applied: production of detergent formulations; organic synthesis, focusing on kinetic resolution, production of biodiesel, and production of food and feed products. The analysis was made based on research publications and patent applications, working as scientific and technological indicators, respectively. Their evolution, interaction, the major players of each sector and the main subject matters disclosed in patent documents were discussed. Applying the concept of technology life cycle, S-curves were built by plotting cumulative patent data over time to monitor the attractiveness of each technology for investment. The results lead to a conclusion that the use of lipases as biocatalysts is still a relevant topic for the industrial sector, but developments are still needed for lipase biocatalysis to reach its full potential, which are expected to be achieved within the third, and present, wave of biocatalysis.


Assuntos
Biocatálise , Biotecnologia/tendências , Lipase/química , Ração Animal , Animais , Biocombustíveis , Detergentes/síntese química , Detergentes/química , Indústria Alimentícia , Previsões , Humanos , Patentes como Assunto/estatística & dados numéricos , Publicações/estatística & dados numéricos
19.
Transfus Apher Sci ; 52(2): 237-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25748229

RESUMO

In recent Coimbra' Conference, on the pre-launch of pathogen reduced-FFP for the local clinical use, the question was raised, by the moderator, on the efficacy of the current methodology used for prion removal processes and its influence on the overall quality and safety of the final product. This brief paper put together by speaker of this session and the moderator, as a consensus of opinions, which was largely discussed during Q&A session, to make it available to a large group of readers of transfusion apheresis science, who might be interested to this topic. In short the capacity of the current process of Octaplas to remove prion is in order of 5.6 log10/ID50 reduction based on several animal studies. Moreover the changes in coagulation and inhibitors are within acceptable range and bioequivalent to untreated FFP with no sign of inferiority. This paper describes in brief a technology update on solvent/detergent treated plasma, an alternative to FFP but with increased pathogen safety. The biochemical profile of the final product is comparable with FFP and contains all clinically relevant plasma proteins. Furthermore, Octaplas is a product that, in long term, reduces health care costs.


Assuntos
Segurança do Sangue/métodos , Cromatografia de Afinidade/métodos , Doenças Priônicas/prevenção & controle , Príons/isolamento & purificação , Animais , Bioensaio , Coagulação Sanguínea , Remoção de Componentes Sanguíneos , Transfusão de Componentes Sanguíneos , Proteínas Sanguíneas/análise , Análise Custo-Benefício , Detergentes/química , Custos de Cuidados de Saúde , Hemostasia , Humanos , Indústrias , Segurança do Paciente , Plasma , Doenças Priônicas/transmissão , Solventes/química
20.
Langmuir ; 31(23): 6267-76, 2015 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-25402969

RESUMO

Biosensors are ideally portable, low-cost tools for the rapid detection of pathogens, proteins, and other analytes. The global biosensor market is currently worth over 10 billion dollars annually and is a burgeoning field of interdisciplinary research that is hailed as a potential revolution in consumer, healthcare, and industrial testing. A key barrier to the widespread adoption of biosensors, however, is their cost. Although many systems have been validated in the laboratory setting and biosensors for a range of analytes are proven at the concept level, many have yet to make a strong commercial case for their acceptance. Though it is true with the development of cheaper electrodes, circuits, and components that there is a downward pressure on costs, there is also an emerging trend toward the development of multianalyte biosensors that is pushing in the other direction. One way to reduce the cost that is suitable for certain systems is to enable their reuse, thus reducing the cost per test. Regenerating biosensors is a technique that can often be used in conjunction with existing systems in order to reduce costs and accelerate the commercialization process. This article discusses the merits and drawbacks of regeneration schemes that have been proven in various biosensor systems and indicates parameters for successful regeneration based on a systematic review of the literature. It also outlines some of the difficulties encountered when considering the role of regeneration at the point of use. A brief meta-analysis has been included in this review to develop a working definition for biosensor regeneration, and using this analysis only ∼60% of the reported studies analyzed were deemed a success. This highlights the variation within the field and the need to normalize regeneration as a standard process across the field by establishing a consensus term.


Assuntos
Técnicas Biossensoriais/instrumentação , Anticorpos/química , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/economia , Técnicas Biossensoriais/métodos , Análise Custo-Benefício , Detergentes/química , Técnicas Eletroquímicas , Eletrodos/economia , Reutilização de Equipamento , Glicina/química , Concentração de Íons de Hidrogênio , Som , Termodinâmica
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