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1.
Braz. J. Pharm. Sci. (Online) ; 59: e22099, 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1439517

RESUMO

Abstract In this study, the manufacturing process of lamivudine (3TC) and zidovudine (AZT) tablets (150+300 mg respectively) was evaluated using statistical process control (SPC) tools. These medicines are manufactured by the Fundação para o Remédio Popular "Chopin Tavares de Lima" (FURP) laboratory, and are distributed free of charge to patients infected with HIV by the Ministry of Health DST/AIDS national program. Data of 529 batches manufactured from 2012 to 2015 were collected. The critical quality attributes of weight variation, uniformity of dosage units, and dissolution were evaluated. Process stability was assessed using control charts, and the capability indices Cp, Cpk, Pp, and Ppk (process capability; process capability adjusted for non-centered distribution; potential or global capability of the process; and potential process capability adjusted for non-centered distribution, respectively) were evaluated. 3TC dissolution data from 2013 revealed a non-centered process and lack of consistency compared to the other years, showing Cpk and Ppk lower than 1.0 and the chance of failure of 2,483 in 1,000,000 tablets. Dissolution data from 2015 showed process improvement, revealed by Cpk and Ppk equal to 2.19 and 1.99, respectively. Overall, the control charts and capability indices showed the variability of the process and special causes. Additionally, it was possible to point out the opportunities for process changes, which are fundamental for understanding and supporting a continuous improvement environment.


Assuntos
Comprimidos/análise , Zidovudina/agonistas , HIV/patogenicidade , Lamivudina/agonistas , Pacientes/classificação , Gestão da Qualidade Total/organização & administração , Honorários e Preços/estatística & dados numéricos , Laboratórios/classificação , Manufaturas/provisão & distribuição
2.
Toxicol Lett ; 351: 135-144, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34500033

RESUMO

This article provides guidance into the quantitative risk assessment of skin exposures to metals. The use of wipe sampling methodologies has been shown to be standardised and effective for skin exposure assessment to metals. However, there is a lack of guidance documents and frameworks available to evaluate the level of health risk to workers from skin exposures to metals. Adverse health effects from exposures to metals have been described in the literature (Fernández-Nieto et al. 2006; Herman et al. 2006; Kreiss et al. 1996). Monitoring of workplace exposures typically focuses on the assessment of respiratory exposures. To provide a safe workplace there is a need to ensure all routes of exposure are risk assessed and controlled. The goal of this article was to develop skin (surface) exposure limits to metals, using the construction industry as a test environment, to quantitatively assess worker health risk of skin exposures to metals. This research concluded it was not feasible to establish single quantitative skin exposure limits to metals due to the many assumptions surrounding dermal exposures. A range of acceptable exposure limits are presented.


Assuntos
Metais/administração & dosagem , Exposição Ocupacional/prevenção & controle , Pele/efeitos dos fármacos , Animais , Testes de Carcinogenicidade , Indústria da Construção , Monitoramento Ambiental , Humanos , Manufaturas , Concentração Máxima Permitida , Metais/toxicidade , Medição de Risco
3.
J Environ Manage ; 285: 112110, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33561728

RESUMO

Asbestos management in Korea has, to date, focused exclusively on dismantlement and removal; however, the effective management of asbestos in public facilities and rural dwellings is also critical. This study compares eight different asbestos stabilization treatments and their effectiveness in reducing asbestos fiber dispersion from weathered corrugated asbestos cement sheets (CACS) under different wind conditions. The effectiveness of the different asbestos stabilizers was assessed in order to identify the characteristics of fibers dispersed from treated CACS samples. The impact of wind speed on the concentration and composition of the dispersed fibers was also evaluated. For all wind speeds, the concentration of the fibers dispersed from the CACS samples that were treated with stabilizers decreased relative to the untreated CACS. These results show that asbestos concentrations were considerably reduced following stabilizer treatment and that treated CACS dispersed fewer asbestos fibers relative to untreated CACS. The results of this study will be useful for the development of strategies regarding the appropriate management of asbestos in public buildings.


Assuntos
Amianto , Amianto/análise , Materiais de Construção , Manufaturas , República da Coreia , Tempo (Meteorologia)
4.
Int J Biol Macromol ; 171: 262-274, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33421466

RESUMO

The active emulsified blend films based on gelatin-pectin (5% w/w) containing virgin olive oil (VOO) (0.1-0.3 g/g biopolymer) and grape seed oil (GSO) (0.1-0.3 g/g biopolymer) were prepared by casting method. GSO showed slightly more decreasing effect than VOO on ultimate tensile strength (UTS) and strain at break (SAB) of blend films however; VOO had more reducing effect than GSO on the water vapor permeability (WVP). The scanning electron microscopy (SEM) images showed that incorporating 0.3 g GSO and VOO oils had not considerable effect on the morphology of the emulsified films. Atomic force microscopy (AFM) topography images indicated that adding of oils considerably could increase roughness of emulsified film. Fourier transforms infrared (FTIR) revealed that no new chemical bond formed by adding oils into biopolymer matrix. The minimum inhibitory concentration (MIC) of VOO, GSO and Savory essential oil (SEO) against four important spoilage bacteria showed that GSO had higher antibacterial effect than VOO however; both showed very lower antimicrobial effect than SEO. All active films showed lower inhibitory zone for S. aureus than S. typhimurium and P. fluorescence. The chicken breast fillets wrapped in the films containing VOO-GSO-SEO (0.15-0.15-0.02 g/g polymer) showed considerably lower total viable count (TVC), Pseudomonas spp., Enterobacteriaceae, E. coli 157:H7 and S. typhimurium count than the control one during 12 days storage. Also, it caused significant decrease in peroxide value (PV), thiobarbituric acid reactive substances (TBARS) and total volatile basic nitrogen (TVB-N) of fillet samples.


Assuntos
Anti-Infecciosos/farmacologia , Embalagem de Alimentos , Gelatina/efeitos dos fármacos , Extrato de Sementes de Uva/química , Manufaturas , Óleos Voláteis/farmacologia , Azeite de Oliva/farmacologia , Pectinas/farmacologia , Óleos de Plantas/farmacologia , Animais , Galinhas , Emulsões , Gelatina/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Teste de Materiais , Carne/análise , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Nitrogênio/análise , Permeabilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Resistência à Tração , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Vitis/química
6.
J Mater Chem B ; 8(38): 8820-8829, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33026393

RESUMO

A new and straightforward route to produce polymeric hollow microfibers has been proposed. Polycaprolactone (PCL) hollow fibers are obtained for the first time using an environmentally friendly gas dissolution foaming approach, overcoming its limitations to induce porosity on samples in the micrometric range. Different porous morphologies are achieved from solid PCL microfibers with a well-controlled diameter obtained by conventional electrospinning. The optimization of the foaming parameters provides two sets of well-defined hollow fibers, one showing smooth surfaces and the other presenting an enhanced surface porosity. Accordingly, gas dissolution foaming proves to be not only suitable for the production of hollow polymeric microfibers, but is also capable of providing diverse porous morphologies from the same precursor, solid fibers. Moreover, a preliminary study about the suitability of this new generation of foamed hollow polymeric fibers for drug delivery is carried out, aiming to take advantage of the enhanced surface area and tunable morphology obtained by using the proposed new production method. It is found that the foamed microfibers can be loaded with up to 15 wt% of ibuprofen while preserving the morphology of each kind of fiber. Then, foamed PCL fibers presenting a hollow structure and surface porosity show a remarkable constant release of ibuprofen for almost one and a half days. In contrast, the original solid fibers do not present such behavior, releasing all the ibuprofen in about seven hours.


Assuntos
Poliésteres/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Ibuprofeno/química , Manufaturas , Porosidade
7.
Int J Biol Macromol ; 164: 27-36, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32673719

RESUMO

It has been a huge challenge to obtain simultaneously excellent mechanical strength and desirable multifunctionality from the cellulose nanocrystals (CNC) based food packing materials. In this work, we demonstrated a hydrogen bonding tailoring strategy that can produce CNC/lignin films with UV blocking and antioxidant activity, while bypassing the loss of mechanical strength. Using a hyperbranched polyester, lignin was first functionalized to increase the amount of hydroxyl groups, thereby increasing the intermolecular interactions. By assembling the polyester modified lignin (H-lignin) into CNC matrix, the hydrogen bonding crosslinks between the H-lignin and CNC chains were successfully promoted, resulting in the CNC composites with the significantly improved mechanical strength, UV blocking and antioxidant activity. The phenolic structure and the hydrogen donation of H-lignin also endowed the resulting CNC composites with excellent UV blocking and antioxidant activity. The experimental results indicated that the H-lignin could bring about 34% and 63% increase in tensile strength and Young's modulus, respectively, higher than the reported ones. The CNC-based composites showed better thermal stability and improved crystallinity property. The H-lignin provides a new insight into the multifunctional exploration of CNC-based composite. This work opens a new avenue for the next generation's biodegradable food packing materials from cellulose-sourced composites.


Assuntos
Antioxidantes/química , Celulose/química , Embalagem de Alimentos , Lignina/química , Manufaturas , Nanopartículas/química , Biodegradação Ambiental , Celulose/efeitos da radiação , Módulo de Elasticidade , Ligação de Hidrogênio , Lignina/efeitos da radiação , Teste de Materiais , Poliésteres/química , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Resistência à Tração , Termogravimetria , Raios Ultravioleta , Molhabilidade
8.
Molecules ; 25(7)2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32225094

RESUMO

Thermal black (TB) is one of the purest and cleanest forms of carbon black (CB) commercially available. TB is manufactured by the decomposition of natural gas in the absence of oxygen while the common furnace CB is derived from the burning of organic oil. TB has a larger particle size, a lower surface area, and lower level of particle aggregation, while being the most eco-friendly grade among the CB family. This study is the first-time evaluation of TB as filler in composites and hybrids based on thermoplastics such as polypropylene (PP), polyamide 6 (PA6), polyphenylene sulfide (PPS), and acrylonitrile butadiene styrene (ABS). TB loadings in composites were varied from 1 up to 40 wt. % and, in hybrids, the TB was used in combination with carbon fibers (CFs) at total contents up to 20 wt. %. TB-containing composites and hybrids based on PA6 and ABS were also extruded in filaments, used in 3D printing, and the obtained 3D printed parts were characterized. TB provided a very high loadability in thermoplastics while preserving their viscosity and performance. TB can replace a fraction of expensive CFs in composites without important changes in the composites' performance. The composites and hybrids exhibited electrical resistivity and good mechanical and thermal properties when compared to commercial compounds, while enabling significant cost savings. TB also showed to be an excellent coloring agent. TB proved to be an outstanding eco-filler for compounds to be used in injection molding and 3D printing technologies.


Assuntos
Filtração , Plásticos , Impressão Tridimensional , Fuligem/química , Condutividade Elétrica , Manufaturas , Fenômenos Mecânicos , Tamanho da Partícula , Termodinâmica , Viscosidade
10.
Mikrochim Acta ; 187(4): 247, 2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-32219540

RESUMO

Surface-enhanced Raman spectroscopy (SERS) is gaining importance as an ultrasensitive analytical tool for routine high-throughput analysis of a variety of molecular compounds. One of the main challenges is the development of robust, reproducible and cost-effective SERS substrates. In this work, we study the SERS activity of 3D silver mirror-like micro-pyramid structures extended in the z-direction up to 3.7 µm (G0 type substrate) or 7.7 µm (G1 type substrate), prepared by Si-based microfabrication technologies, for trace detection of organophosphorous pesticides, using paraoxon-methyl as probe molecule. The average relative standard deviation (RSD) for the SERS intensity of the peak displayed at 1338 cm-1 recorded over a centimetre scale area of the substrate is below 13% for pesticide concentrations in the range 10-6 to 10-15 mol L-1. This data underlies the spatial uniformity of the SERS response provided by the microfabrication approach. According to finite-difference time-domain (FDTD) simulations, such remarkable feature is mainly due to the contribution on electromagnetic field enhancement of edge plasmon polaritons (EPPs), propagating along the pyramid edges where the pesticide molecules are preferentially adsorbed. Graphical abstract.


Assuntos
Manufaturas , Paraoxon/análogos & derivados , Praguicidas/análise , Prata/química , Adsorção , Paraoxon/análise , Paraoxon/química , Praguicidas/química , Reprodutibilidade dos Testes , Análise Espectral Raman/métodos
11.
Molecules ; 25(4)2020 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-32079079

RESUMO

Inorganic-organic hybrids are a group of materials that have recently become the subject of intense scientific research. They exhibit some of the specific properties of both highly durable inorganic materials (e.g., titanium dioxide, zinc) and organic products with divergent physicochemical traits (e.g., lignin, chitin). This combination results in improved physicochemical, thermal or mechanical properties. Hybrids with defined characteristics can be used as fillers for polymer composites. In this study, three types of filler with different MgO/lignin ratio were used as fillers for polypropylene (PP). The effectiveness of MgO-lignin binding was confirmed using Fourier transform infrared spectroscopy. The fillers were also tested in terms of thermal stability, dispersive-morphological properties as well as porous structure. Polymer composites containing 3 wt.% of each filler were subjected to wide angle X-ray diffraction tests, differential scanning calorimetry and microscopic studies to define their structure, morphology and thermal properties. Additionally, tensile tests of the composites were performed. It was established that the composition of the filler has a significant influence on the crystallization of polypropylene-either spherulites or transcrystalline layers were formed. The value of Young's modulus and tensile strength remained unaffected by filler type. However, composites with hybrid fillers exhibited lower elongation at break than unfilled polypropylene.


Assuntos
Lignina/química , Óxido de Magnésio/química , Manufaturas/análise , Polipropilenos/química , Cristalização , Módulo de Elasticidade , Humanos , Teste de Materiais , Porosidade , Estresse Mecânico , Resistência à Tração
12.
Nanotoxicology ; 14(2): 275-286, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31928272

RESUMO

The major theme of the NRC report "Toxicity Testing in the Twenty-first Century" is to replace animal testing by using alternative in vitro methods. Therefore, it can be expected that in the future in vivo data will be replaced with in vitro data. Hence, there is a need for new strategies to make use of the increasing amount of in vitro data when developing human toxicological effect factors (HEF) to characterize the impact category of human toxicity in life cycle assessment (LCA). Here, we present a new approach for deriving HEF for manufactured nanomaterials (MNMs) based on the combined use of in vitro toxicity data and a relative potency factor (RPF) approach. In vitro toxicity tests with nano-CuO, nano-Ag and nano-ZnO and their corresponding ions were performed on THP-1, CaCo-2 and Hep-G2 cell lines. The ratio of the here calculated EC50 of the ionic form and the nanoform corresponds to the Relative Potency Factor (RPF). Using this approach, HEFs (case/kgintake) for the aforementioned nanoparticles were obtained. Non-carcinogenic HEFs (case/kgintake) for exposure via ingestion of 5.9E-01, 7.5E-03 and 2.5 E-02 were calculated for nano-Ag, nano-CuO and nano-ZnO, respectively. The HEF values here proposed were compared with HEF values extrapolated from in vivo toxicity data reported in the literature. The here presented procedure is the most appropriate approximation currently available for using in vitro toxicity data on MNM for application in the field of LCIA.


Assuntos
Cobre/toxicidade , Manufaturas/toxicidade , Nanopartículas Metálicas/toxicidade , Modelos Teóricos , Prata/toxicidade , Óxido de Zinco/toxicidade , Animais , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Íons , Medição de Risco , Células THP-1 , Testes de Toxicidade
13.
Cytotherapy ; 21(12): 1198-1205, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31837735

RESUMO

Tisagenlecleucel, a CD19-specific autologous chimeric antigen receptor (CAR)-T cell therapy, is efficacious for the treatment of relapsed/refractory B-cell precursor acute lymphoblastic leukemia and diffuse large B-cell lymphoma. The tisagenlecleucel manufacturing process was initially developed in an academic setting and subsequently transferred to industry for qualification, validation and scaling up for global clinical trials and commercial distribution. Use of fresh leukapheresis material was recognized early on in the transfer process as a challenge with regard to establishing a global supply chain. To maximize manufacturing success rates and to overcome logistical challenges, cryopreservation was adapted into the Novartis manufacturing process from the beginning of clinical trials. Tisagenlecleucel manufactured in centralized facilities with cryopreserved leukapheresis material has been used successfully in global clinical trials at more than 50 clinical centers in 12 countries. Cryopreservation provides flexibility in scheduling leukapheresis when the patient's health is optimal to provide T cells; it also provides protection from external factors, such as shipping delays, and removes manufacturing time constraints. Several studies were performed to establish comparability of fresh versus cryopreserved leukapheresis material, to evaluate and optimize the cryopreservation process, to determine the optimal temperature and maximum hold time prior to cryopreservation and to determine the optimal temperature range for shipment and storage. Using the current validated industry manufacturing process, high success rates were achieved with regard to manufacturing tisagenlecleucel batches that met specifications and were released to patients. Consistent product quality and positive clinical outcomes support the use of cryopreserved non-mobilized peripheral mononuclear blood cells collected using leukapheresis for CAR-T cell manufacturing.


Assuntos
Criopreservação/métodos , Leucaférese , Manufaturas , Receptores de Antígenos de Linfócitos T , Antígenos CD19/imunologia , Criopreservação/normas , Indústria Farmacêutica/métodos , Indústria Farmacêutica/tendências , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Humanos , Imunoterapia Adotiva/métodos , Leucaférese/métodos , Leucaférese/tendências , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos Quiméricos , Linfócitos T/imunologia , Temperatura
14.
Cytotherapy ; 21(11): 1166-1178, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31668486

RESUMO

BACKGROUND: Although dendritic cell (DC)-based cancer vaccines represent a promising treatment strategy, its exploration in the clinic is hampered due to the need for Good Manufacturing Practice (GMP) facilities and associated trained staff for the generation of large numbers of DCs. The Quantum bioreactor system offered by Terumo BCT represents a hollow-fiber platform integrating GMP-compliant manufacturing steps in a closed system for automated cultivation of cellular products. In the respective established protocols, the hollow fibers are coated with fibronectin and trypsin is used to harvest the final cell product, which in the case of DCs allows processing of only one tenth of an apheresis product. MATERIALS AND RESULTS: We successfully developed a new protocol that circumvents the need for fibronectin coating and trypsin digestion, and makes the Quantum bioreactor system now suitable for generating large numbers of mature human monocyte-derived DCs (Mo-DCs) by processing a complete apheresis product at once. To achieve that, it needed a step-by-step optimization of DC-differentiation, e.g., the varying of media exchange rates and cytokine concentration until the total yield (% of input CD14+ monocytes), as well as the phenotype and functionality of mature Mo-DCs, became equivalent to those generated by our established standard production of Mo-DCs in cell culture bags. CONCLUSIONS: By using this new protocol for the Food and Drug Administration-approved Quantum system, it is now possible for the first time to process one complete apheresis to automatically generate large numbers of human Mo-DCs, making it much more feasible to exploit the potential of individualized DC-based immunotherapy.


Assuntos
Reatores Biológicos , Remoção de Componentes Sanguíneos , Vacinas Anticâncer , Técnicas de Cultura de Células , Células Dendríticas/citologia , Células Dendríticas/fisiologia , Monócitos/fisiologia , Automação Laboratorial/normas , Reatores Biológicos/normas , Remoção de Componentes Sanguíneos/instrumentação , Remoção de Componentes Sanguíneos/métodos , Remoção de Componentes Sanguíneos/normas , Vacinas Anticâncer/normas , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Indústria Farmacêutica/instrumentação , Indústria Farmacêutica/normas , Fidelidade a Diretrizes , Humanos , Imunoterapia Adotiva/métodos , Imunoterapia Adotiva/normas , Leucaférese/instrumentação , Leucaférese/métodos , Leucaférese/normas , Manufaturas/normas , Monócitos/citologia
15.
Biofouling ; 35(8): 870-882, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31603038

RESUMO

Steel marine structures provide foci of biodiversity when they develop into artificial reefs. Development begins with deposition of a biofilm. The effects of contaminants from oil spills on biofilm microbiomes, microbially-induced corrosion (MIC) and metal loss may impact preservation of marine metal structures. A microcosm experiment exposed biofilms on carbon steel disks (CSDs) to crude oil, dispersant, and dispersed oil to address their impacts on bacterial composition and metal loss and pitting. Biofilm diversity increased over time in all exposures. Community composition in dispersant and dispersed oil treatments deviated from the controls for the duration of a 12-week experiment. As biofilms matured, Pseudomonadaceae increased while Rhodobacteraceae decreased in abundance in dispersed oil treatments compared to the controls and dispersant treatments. Greatest mass loss and deepest pitting on CSDs were observed in dispersed oil treatments, suggesting impacts manifest as a consequence of increased MIC potential on carbon steel.


Assuntos
Biofilmes/efeitos dos fármacos , Manufaturas/microbiologia , Microbiota/efeitos dos fármacos , Poluição por Petróleo/efeitos adversos , Proteobactérias/efeitos dos fármacos , Aço , Biodiversidade , Biofilmes/crescimento & desenvolvimento , Carbono/química , Corrosão , Petróleo/análise , Petróleo/toxicidade , Poluição por Petróleo/análise , Proteobactérias/classificação , Proteobactérias/isolamento & purificação , RNA Ribossômico 16S/genética , Aço/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
16.
Bioengineered ; 10(1): 397-408, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31526157

RESUMO

Nowadays, there is an increasing concern toward substituting the scarce wood fibers with alternative lignocellulosic fibers that originate from crop residue to reinforce biocomposites. In this paper, the potential application of coffee hull (CH) of the reinforced polyethylene (PE) matrix composites was studied for the first time. Experiments of composite that enhanced with CH on mechanical properties, hydroscopicity, thermogravimetric analysis, fiber treatment, and microstructures were tested in this study. The PE matrix was reinforced with varying volume fractions of CH and was studied. The results show that incorporation of coffee hull markedly improved the mechanical properties of the reinforced high-density polyethylene (HDPE) matrix composites. Micrographs show a strong interfacial adhesion between the CH fiber particles. This property may be the main reason for the stability between composites. At the same time this work investigated the effect of different treatments on the mechanical properties and water absorption behavior of composites. The fiber surface treatments were done using active chemicals such as calcium hydroxide (Ca(OH)2), silane coupling agent (SCA), maleic anhydride grafted polypropylene (MA-g-PP), stearic acid (SA), ethylene bis stearamide (EBS) and the combination (MA-g-PP, SA, EBS). The results show that (Ca(OH)2)treatment is the best way to improve its properties. Probably because attributed to removal of surface active functional groups (-OH) from the CH fiber and induction of hydrophobicity that in turn improved the compatibility with the polymer matrix. As a result, the use of coffee hull in composites could have great significance for the industry.


Assuntos
Café/química , Manufaturas , Plásticos/síntese química , Polietileno/química , Hidróxido de Cálcio/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Anidridos Maleicos/química , Teste de Materiais , Plásticos/química , Silanos/química , Ácidos Esteáricos/química , Temperatura , Resistência à Tração , Resíduos , Molhabilidade
17.
Molecules ; 24(18)2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31540149

RESUMO

Due to their numerous health benefits associated with various diseases and anti-oxidation properties, the phenolic compounds collectively referred to as phytochemicals have attracted a lot of interest, however, a single extraction method for polyphenols has not been developed yet. Supercritical fluid extraction, a green extraction method, provides the final product without organic solvent residues. In this work the extraction of lavender was performed using supercritical carbon dioxide. A statistical experimental design based on the Box-Behnken (B-B) method was planned, and the extraction yields and total phenolic contents were measured for three different variables: pressure, temperature and extraction time. The ranges were 200-300 bar, 40-60 °C and 15-45 min. The extracts yields from scCO2 extraction were in the range of 4.3-9.2 wt.%. The highest yield (9.2 wt.%) was achieved at a temperature of 60 °C under the pressure of 250 bar after 45 min. It also corresponded to the highest total phenolic content (10.17 mg GAE/g extract). Based on the study, the statistically generated optimal extraction conditions to obtain the highest total phenolic compounds concentration from flowers of Lavandula angustifolia were a temperature of 54.5 °C, pressure of 297.9 bar, and the time of 45 min. Based on the scavenging activity percentage (AA%) of scCO2 extracts, it is concluded that the increase of extraction pressure had a positive influence on the increase of AA% values.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Flores/química , Lavandula/química , Polifenóis/isolamento & purificação , Dióxido de Carbono/química , Manufaturas/economia , Fenóis/análise , Fenóis/isolamento & purificação , Extratos Vegetais/química , Polifenóis/análise , Pressão , Projetos de Pesquisa , Solventes/química , Temperatura , Tempo
18.
MMWR Morb Mortal Wkly Rep ; 68(38): 813-818, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31557149

RESUMO

Silicosis is an incurable occupational lung disease caused by inhaling particles of respirable crystalline silica. These particles trigger inflammation and fibrosis in the lungs, leading to progressive, irreversible, and potentially disabling disease. Silica exposure is also associated with increased risk for lung infection (notably, tuberculosis), lung cancer, emphysema, autoimmune diseases, and kidney disease (1). Because quartz, a type of crystalline silica, is commonly found in stone, workers who cut, polish, or grind stone materials can be exposed to silica dust. Recently, silicosis outbreaks have been reported in several countries among workers who cut and finish stone slabs for countertops, a process known as stone fabrication (2-5). Most worked with engineered stone, a manufactured, quartz-based composite material that can contain >90% crystalline silica (6). This report describes 18 cases of silicosis, including the first two fatalities reported in the United States, among workers in the stone fabrication industry in California, Colorado, Texas, and Washington. Several patients had severe progressive disease, and some had associated autoimmune diseases and latent tuberculosis infection. Cases were identified through independent investigations in each state and confirmed based on computed tomography (CT) scan of the chest or lung biopsy findings. Silica dust exposure reduction and effective regulatory enforcement, along with enhanced workplace medical and public health surveillance, are urgently needed to address the emerging public health threat of silicosis in the stone fabrication industry.


Assuntos
Manufaturas/efeitos adversos , Indústria Manufatureira , Exposição Ocupacional/efeitos adversos , Silicose/diagnóstico , Adulto , California/epidemiologia , Colorado/epidemiologia , Evolução Fatal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Silicose/epidemiologia , Texas/epidemiologia , Washington/epidemiologia
19.
Environ Sci Pollut Res Int ; 26(29): 29991-30002, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31414386

RESUMO

The microbial corrosion of oil and gas pipes is one of the problems occurring in the oil industry. Various mechanisms explaining microbial corrosion have been demonstrated. Commonly, biocorrosion is attributed to sulfate-reducing bacteria. Also, it has recently been reported that microbial species can connect their electron transport system to metal electrodes. In this research, two spore-forming bacteria isolated in different years from a gas pipeline were identified by biochemical techniques and by 16S rDNA amplification, sequencing, and comparison with the NCBI database. Isolates were also compared between them using molecular techniques as the restriction patterns, unique for 16S rDNA (ARDRA), and the profile of the amplified bit from the genomic DNA, using an unspecific primer (RAPD). The results obtained showed that both isolates corresponded to Clostridium celerecrescens with a 99% similarity according to the sequence reported on the NCBI database. Also, the ARDRA and RAPD electrophoretic profiles of both strains were identical, and no plasmids were found in the strains. Thus, it can be settled that this bacterium is persistent in the environment prevailing in gas pipelines. Also, it was demonstrated that the bacterial secretion of organic acids contributes to the pitting and general biocorrosion of API XL 52 steel. The rates of corrosion obtained, approximately after 40 days, were correlated with the presence and metabolic activity of C. celerecrescens on the metallic surfaces.


Assuntos
Biofilmes/crescimento & desenvolvimento , Clostridium/isolamento & purificação , Corrosão , Manufaturas/microbiologia , Aço , Anaerobiose , DNA Ribossômico/genética , RNA Ribossômico 16S/genética
20.
Transfusion ; 59(9): 2952-2963, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31294868

RESUMO

BACKGROUND: Rejuvenation of stored red blood cells (RBCs) increases levels of adenosine 5'-triphosphate (ATP) and 2,3-diphosphoglycerate (2,3-DPG) to those of fresh cells. This study aimed to optimize and validate the US-approved process to a UK setting for manufacture and issue of rejuvenated RBCs for a multicenter randomized controlled clinical trial in cardiac surgery. STUDY DESIGN AND METHODS: Rejuvenation of leukoreduced RBC units involved adding a solution containing pyruvate, inosine, phosphate, and adenine (Rejuvesol, Zimmer Biomet), warming at 37°C for 60 minutes, then "manual" washing with saline adenine glucose mannitol solution. A laboratory study was conducted on six pools of ABO/D-matched units made the day after donation. On Days 7, 21, and 28 of 4 ± 2°C storage, one unit per pool was rejuvenated and measured over 96 hours for volume, hematocrit, hemolysis, ATP, 2,3-DPG, supernatant potassium, lactate, and purines added (inosine) or produced (hypoxanthine) by rejuvenation. Subsequently, an operational validation (two phases of 32 units each) was undertaken, with results from the first informing a trial component specification applied to the second. Rejuvenation effects were also tested on crossmatch reactivity and RBC antigen profiles. RESULTS: Rejuvenation raised 2,3-DPG to, and ATP above, levels of fresh cells. The final component had potassium and hemolysis values below those of standard storage Days 7 and 21, respectively, containing 1.2% exogenous inosine and 500 to 1900 µmoles/unit of hypoxanthine. The second operational validation met compliance to the trial component specification. Rejuvenation did not adversely affect crossmatch reactivity or RBC antigen profiles. CONCLUSION: The validated rejuvenation process operates within defined quality limits, preserving RBC immunophenotypes, enabling manufacture for clinical trials.


Assuntos
Preservação de Sangue/métodos , Eritrócitos/fisiologia , Medicina Regenerativa/métodos , Rejuvenescimento/fisiologia , 2,3-Difosfoglicerato/metabolismo , Trifosfato de Adenosina/sangue , Tipagem e Reações Cruzadas Sanguíneas , Perda Sanguínea Cirúrgica/prevenção & controle , Preservação de Sangue/normas , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Criopreservação/métodos , Contagem de Eritrócitos , Transfusão de Eritrócitos/normas , Eritrócitos/citologia , Hemólise/fisiologia , Humanos , Imunofenotipagem , Manufaturas , Purinas/sangue , Controle de Qualidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Medicina Regenerativa/normas
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