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1.
Int J Mol Sci ; 25(9)2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38732243

RESUMO

This study presents the functionalization of silk fabric with SWCNT ink. The first step was the formation of a polydopamine (PDA) thin coating on the silk fabric to allow for effective bonding of SWCNTs. PDA formation was carried out directly on the fabric by means of polymerization of dopamine in alkali conditions. The Silk/PDA fabric was functionalized with SWCNT ink of different SWCNT concentrations by using the dip-coating method. IR and Raman analyses show that the dominant ß-sheet structure of silk fibroin after the functionalization process remains unchanged. The heat resistance is even slightly improved. The hydrophobic silk fabric becomes hydrophilic after functionalization due to the influence of PDA and the surfactant in SWCNT ink. The ink significantly changes the electrical properties of the silk fabric, from insulating to conductive. The volume resistance changes by nine orders of magnitude, from 2.4 × 1012 Ω to 2.3 × 103 Ω for 0.12 wt.% of SWCNTs. The surface resistance changes by seven orders of magnitude, from 2.1 × 1012 Ω to 2.4 × 105 Ω for 0.17 wt.% of SWCNTs. The volume and surface resistance thresholds are determined to be about 0.05 wt.% and 0.06 wt.%, respectively. The low value of the percolation threshold indicates efficient functionalization, with high-quality ink facilitating the formation of percolation paths through SWCNTs and the influence of the PDA linker.


Assuntos
Condutividade Elétrica , Indóis , Tinta , Nanotubos de Carbono , Polímeros , Seda , Indóis/química , Polímeros/química , Seda/química , Nanotubos de Carbono/química , Têxteis , Interações Hidrofóbicas e Hidrofílicas
2.
RSC Adv ; 13(49): 34681-34692, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38035250

RESUMO

Cotton textiles modified with copper compounds have a documented mechanism of antimicrobial action against bacteria, fungi, and viruses. During the COVID-19 pandemic, there was pronounced interest in finding new solutions for textile engineering, using modifiers and bioactive methods of functionalization, including introducing copper nanoparticles and complexes into textile products (e.g. masks, special clothing, surface coverings, or tents). However, copper can be toxic, depending on its form and concentration. Functionalized waste may present a risk to the environment if not managed correctly. Here, we present a model for managing copper-modified cotton textile waste. The process includes pressure and temperature-assisted hydrolysis and use of the hydrolysates as a source of sugars for cultivating yeast and lactic acid bacteria biomass as valuable chemical compounds.

3.
Biomater Adv ; 153: 213582, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37591178

RESUMO

The anticancer potential of quercetin (Q), a plant-derived flavonoid, and underlining molecular mechanisms are widely documented in cellular models in vitro. However, biomedical applications of Q are limited due to its low bioavailability and hydrophilicity. In the present study, the electrospinning approach was used to obtain polylactide (PLA) and PLA and polyethylene oxide (PEO)-based micro- and nanofibers containing Q, namely PLA/Q and PLA/PEO/Q, respectively, in a form of non-woven fabrics. The structure and physico-chemical properties of Q-loaded fibers were characterized by scanning electron and atomic force microscopy (SEM and AFM), X-ray powder diffraction (XRD), differential scanning calorimetry (DSC), goniometry and FTIR and Raman spectroscopy. The anticancer action of PLA/Q and PLA/PEO/Q was revealed using two types of cancer and nine cell lines, namely osteosarcoma (MG-63, U-2 OS, SaOS-2 cells) and breast cancer (SK-BR-3, MCF-7, MDA-MB-231, MDA-MB-468, Hs 578T, and BT-20 cells). The anticancer activity of Q-loaded fibers was more pronounced than the action of free Q. PLA/Q and PLA/PEO/Q promoted cell cycle arrest, oxidative stress and apoptotic cell death that was not overcome by heat shock protein (HSP)-mediated adaptive response. PLA/Q and PLA/PEO/Q were biocompatible and safe, as judged by in vitro testing using normal fibroblasts. We postulate that PLA/Q and PLA/PEO/Q with Q releasing activity can be considered as a novel and more efficient micro- and nano-system to deliver Q and eliminate phenotypically different cancer cells.


Assuntos
Neoplasias Ósseas , Quercetina , Humanos , Quercetina/farmacologia , Flavonoides , Apoptose , Disponibilidade Biológica
4.
Cancers (Basel) ; 14(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36358664

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive primary malignancy of the pancreas, with a dismal prognosis and limited treatment options. It possesses a unique tumor microenvironment (TME), generating dense stroma with complex elements cross-talking with each other to promote tumor growth and progression. Diversified neural components makes for not having a full understanding of their influence on its aggressive behavior. The aim of the study was to summarize and integrate the role of nerves in the pancreatic tumor microenvironment. The role of autonomic nerve fibers on PDAC development has been recently studied, which resulted in considering the targeting of sympathetic and parasympathetic pathways as a novel treatment opportunity. Perineural invasion (PNI) is commonly found in PDAC. As the severity of the PNI correlates with a poorer prognosis, new quantification of this phenomenon, distinguishing between perineural and endoneural invasion, could feature in routine pathological examination. The concepts of cancer-related neurogenesis and axonogenesis in PDAC are understudied; so, further research in this field may be warranted. A better understanding of the interdependence between the neural component and cancer cells in the PDAC microenvironment could bring new nerve-oriented treatment options into clinical practice and improve outcomes in patients with pancreatic cancer. In this review, we aim to summarize and integrate the current state of knowledge and future challenges concerning nerve-cancer interactions in PDAC.

5.
Materials (Basel) ; 15(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36079542

RESUMO

Textile structures with various bioactive and functional properties are used in many areas of medicine, special clothing, interior textiles, technical goods, etc. We investigated the effect of two different textile woven structures made of 90% polyester with 10% polyamide (PET) and 100% cotton (CO) modified by magnetron sputtering with copper (Cu) on bioactive properties against Gram-positive and Gram-negative bacteria and four viruses and also on the some comfort parameters. PET/Cu and CO/Cu fabrics have strong antibacterial activity against Staphylococcus aureus and Klebsiella pneumonia. CO/Cu fabric has good antiviral activity in relation to vaccinia virus (VACV), herpes simplex virus type 1 (HSV-1) and influenza A virus H1N1 (IFV), while its antiviral activity against mouse coronavirus (MHV) is weak. PET/Cu fabric showed weak antiviral activity against HSV-1 and MHV. Both modified fabrics showed no significant toxicity in comparison to the control medium and pristine fabrics. After Cu sputtering, fabric surfaces became hydrophobic and the value of the surface free energy was over four times lower than for pristine fabrics. The modification improved thermal conductivity and thermal diffusivity, facilitated water vapour transport, and air permeability did not decrease.

6.
Materials (Basel) ; 15(11)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35683123

RESUMO

The aim of the research was to evaluate the changes in the surface properties of five functional clothing materials with water-repellent finishes (including PFC-free finish) after 1, 5, and 10 washes with three detergents. A new approach to the interpretation of the water-repellent properties of textile materials is presented, based on two techniques, i.e., the spray test method and contact angle measurements. The results showed that washing materials with hydrophobic finishes can cause significant changes in their properties, which are mainly dependent on the composition and structure of the material, as well as the type of hydrophobic finish. The PFC-free finish is the least resistant to washing. For all materials with PFC finishes, the water repellency depends on the fluorine content on the surface and fabric topography. It was also found that increasing washing frequency resulted in a gradual decrease in water repellency. The loss of water repellency below an acceptable level (Grade 3) occurred after the fifth washing for all materials. Significant differences in the interpretation of the results of the spray test and contact angle measurements were observed. Using these methods separately provides information on the changes in the surface properties of the tested materials; however, their parallel application allows for obtaining complementary data, which is important for the proper interpretation of results.

7.
Molecules ; 27(6)2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35335318

RESUMO

New functionalization methods of meta- and para-aramid fabrics with silver nanowires (AgNWs) and two silanes (3-aminopropyltriethoxysilane (APTES)) and diethoxydimethylsilane (DEDMS) were developed: a one-step method (mixture) with AgNWs dispersed in the silane mixture and a two-step method (layer-by-layer) in which the silanes mixture was applied to the previously deposited AgNWs layer. The fabrics were pre-treated in a low-pressure air radio frequency (RF) plasma and subsequently coated with polydopamine. The modified fabrics acquired hydrophobic properties (contact angle ΘW of 112-125°). The surface free energy for both modified fabrics was approximately 29 mJ/m2, while for reference, meta- and para-aramid fabrics have a free energy of 53 mJ/m2 and 40 mJ/m2, respectively. The electrical surface resistance (Rs) was on the order of 102 Ω and 104 Ω for the two-step and one-step method, respectively. The electrical volume resistance (Rv) for both modified fabrics was on the order of 102 Ω. After UV irradiation, the Rs did not change for the two-step method, and for the one-step method, it increased to the order of 1010 Ω. The specific strength values were higher by 71% and 63% for the meta-aramid fabric and by 102% and 110% for the para-aramid fabric for the two-step and one-step method, respectively, compared to the unmodified fabrics after UV radiation.


Assuntos
Nanofios , Prata , Interações Hidrofóbicas e Hidrofílicas , Silanos , Prata/química , Têxteis
8.
Materials (Basel) ; 14(23)2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34885555

RESUMO

Invasive slugs generate significant problems in the area of horticultural and agricultural production. Despite the multitude of methods to reduce the pest population, including preventive, mechanical, agrotechnical, cultivation, biological, and chemical treatments, no effective plant protection strategy has been developed so far. In this paper, a solution based on modified non-woven fabric with bioactive molluscicidal properties using the extract of tansy flower, metaldehyde, and abamectin (Vertigo® 018 EC) was proposed. All modified mats show significant anti-slug properties in comparison to control, and molluscicidal properties depend on the type of active substance. Non-woven modified with commonly used metaldehyde demonstrated fast action against slugs and presents the highest efficiency. The effectiveness of non-woven mats with Vertigo® 018 EC is lower than for the mats with metaldehyde but higher than for the mats modified with tansy flower extract. The proposed solution will enable removing and neutralization of molluscicide from the fields, after the efficient pest control, according to circular economy principles. Moreover, it may allow for better control of the molluscicide release to the environment in comparison to widely used pellets, and contribute to the virtual protection of plants against invasive slugs.

9.
Materials (Basel) ; 14(22)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34832319

RESUMO

Silk, as a protein fiber characterized by high biocompatibility, biodegradability, and low toxicity, is mainly used as textile structures for various purposes, including for biological applications. The key issue for unlimited silk applicability as a modifier is to prepare its relevant form to cover or introduce to other materials. This study presents silk powder fabrication from Bombyx mori cocoons and non-dyed silk woven fabric through cryogenic milling. The cocoons were milled before and after the degumming process to obtain powders from raw structures and pure fibroin. The powder morphology and composition were analyzed using scanning electron microscopy and energy dispersive spectroscopy. The influence of the milling on the silk structure was studied using infrared and Raman spectroscopies, indicating that silk powders retained dominant ß-sheet structure. The powders were also analyzed by differential scanning calorimetry and thermogravimetric techniques. The thermal endothermic peak and onset temperature characteristic for silk decomposition shifted to the lower values for all powders, indicating less thermal stability. However, the process was found to be an efficient way to obtain silk powders. The new milled form of silk can allow its introduction into different matrices or form coatings without using any harsh solvents, enriching them with new features and make more biologically friendly.

10.
ACS Omega ; 6(40): 26077-26085, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34660968

RESUMO

This paper presents the characterization of cotton and wool fabrics modified by silver nanowires (AgNWs). The effect of reactive dyeing of wool and cotton fabrics on their modification with AgNWs was analyzed. Both fabrics were dyed using reactive dyes (yellow, red, blue) at four color intensities (0.5, 1, 2, and 5%). Dyed fabrics were characterized by the determined Kubelka-Munk's coefficient (K/S) ratio and vibrational spectra (Fourier transform infrared (FTIR) and Raman). Analysis of the amount of AgNWs applied on cotton and wool fabrics indicates that the presence of dye affects the surface modification with AgNWs depending on the type of fibers. While for cotton no significant differences were noted in relation to the color intensity, in the case of wool, the higher the dye contents, the more nanowires were deposited on the surface. Surface-enhanced Raman spectroscopy (SERS) effect accompanying AgNW modification was also observed on wool, similar to the previous study on cotton.

11.
Materials (Basel) ; 14(8)2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33920963

RESUMO

Cotton is grown in about 90 countries and accounts for 24% of the fibers used in the global production of textiles. In 2018/2019, 25.8 Mt of cotton were produced around the world. Since this natural product consists mainly of cellulose, it can be used as a raw material in the so-called "sugar economy". This paper discusses a model procedure for thermally assisted acidic hydrolysis of cotton into glucose and subsequent oxidation of the glucose into calcium gluconate over Pd-Au/SiO2 catalyst. In the first step, H2SO4 was used as a catalyst for hydrolysis. The cotton hydrolysates were neutralized using CaCO3 and applied as a substrate in the second step, where glucose was oxidized over Pd-Au/SiO2 prepared by ultrasound assisted co-impregnation. With the appropriate Au/Pd molar ratio, small crystallites of palladium and gold were created which were active and selective towards the formation of gluconate ions. This approach to the transformation of glucose represents as a viable alternative to biological processes using fungal and bacterial species, which are sensitive to the presence of inhibitors such as furfurals and levulinic acid in hydrolysates.

12.
RSC Adv ; 11(7): 4174-4185, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35424341

RESUMO

Since silver nanowires (AgNWs) show high infrared reflectance many studies present their applicability as thermal management products for various wearable textiles. However, their use for practical purposes is only partially evaluated, without focusing on improving their low atmospheric and liquid stability. This report describes a new approach for the topic and proposes a facile method of Ag nanowire passivation with a SnO2 layer for high environmental stability and retention of high infrared reflectance. The one-step passivation process of AgNWs was carried out in the presence of sodium stannate in an aqueous solution at 100 °C, and resulted in the formation of core/shell Ag/SnO2 nanowires. This study presents the morphological, chemical, and structural properties of Ag/SnO2NWs formed with a 14 nm thick SnO2 shell, consisting of 7 nm rutile-type crystals, covering the silver metallic core. The optical properties of the AgNWs changed significantly after shell formation, and the longitudinal and transverse modes in the surface plasmon resonance spectrum were red shifted as a result of the surrounding media dielectric constant changes. The passivation process protected the AgNWs from decomposition in air for over 4 months, and from dissolution in a KCN solution at concentrations up to 0.1 wt%. Moreover, the report shows the microwave irradiation effect on the shell synthesis and previously synthesised Ag/SnO2NWs. The post-synthesis irradiation, as well as the SnO2 shell obtained by microwave assistance, did not allow long-term stability to be achieved. The microwave-assisted synthesis process was also not fast enough to inhibit the formation of prismatic silver structures from the nanowires. The Ag/SnO2NWs with a shell obtained by a simple hydrolysis process, apart from showing high infra-red reflectance on the para-aramid fabric, are highly environmentally stable. The presented SnO2 shell preparation method can protect the AgNW's surface from dissolution or decomposition and facilitate the designing of durable smart wearable thermal materials for various conditions.

13.
Front Psychol ; 11: 525560, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33192766

RESUMO

The acceptance of disability is recognized as one of the most frequently mentioned factors that plays a particularly significant role in subjective well-being. However, so far, only a very small amount of research has been undertaken to clarify how and why acceptance of illness relates to eudemonic well-being. Hence, comprehension of the direct and indirect effects underlying this relationship seems essential for interventions that increase the recovery of people with impairments and enhance their quality of life. The current research was aimed at investigating the association between acceptance of illness, meaning in life, and eudemonic well-being, as well as the possible mediatory effect of meaning in life on the relationship between acceptance of illness and well-being. The sample consisted of 102 participants (71% women) aged between 20 and 64 years. The respondents had a range of different impairments (e.g., cerebral palsy, neurological disorders, spinal muscular atrophy, and sight defects). The Acceptance of Illness Scale, the Meaning in Life Questionnaire, and the Ryff Scales of Psychological Well-Being were used. It was confirmed that acceptance of illness correlated positively and significantly with the presence of meaning, self-acceptance, positive relations, environmental mastery, personal growth, general well-being, cohesion, flexibility, communication, and family satisfaction. The presence of meaning mediated the relationship between acceptance of illness and general well-being with its four other dimensions: self-acceptance, environmental mastery, purpose in life, and personal growth. Conversely, the search for meaning did not have any mediatory effect on this relationship.

14.
Molecules ; 25(15)2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32751649

RESUMO

The aim of the study was to modify the surface free energy (SFE) of meta- (mAr) and para-aramid (pAr) yarns by their activation in low-pressure air radio frequency (RF) (40 kHz) plasma and assessment of its impact on the properties of the yarns. After 10 and 90 min of activation, the SFE value increased, respectively, by 14% and 37% for mAr, and by 10% and 37% for pAr. The value of the polar component increased, respectively by 22% and 57% for mAr and 20% and 62% for pAr. The value of the dispersion component for mAr and pAr increased respectively by 9% and 25%. The weight loss decreased from 49% to 46% for mAr and 62% to 50% for pAr after 90 min of activation. After 90 min, the specific strength for mAr did not change and for pAr it decreased by 40%. For both yarns, the 10 min activation in plasma is sufficient to prepare their surface for planned nanomodification.


Assuntos
Gases em Plasma/química , Polímeros/química , Ondas de Rádio , Humanos , Polímeros/efeitos da radiação
15.
Plants (Basel) ; 8(11)2019 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-31744231

RESUMO

Silver is one of the most toxic heavy metals for plants, inducing various toxic symptoms and metabolic changes. Here, the impact of Ag(I) on Carlina acaulis physiology and selected metabolites was studied using two Ag concentrations (1 or 10 µM) after 14 days of exposure. The higher concentration of Ag(I) evoked reduction of growth, while 1 µM Ag had a growth-promoting effect on root biomass. The translocation factor (<0.04) showed that Ag was mainly retained in the roots. The 1 µM Ag concentration increased the level of low-molecular-weight organic acids (LMWOAs), while 10 µM Ag depleted these compounds in the roots. The increased concentration of Ag(I) elevated the accumulation of phytochelatins (PCs) in the roots and reduced glutathione (GSH) in the shoots (but not in the roots). At 1 µM, Ag(I) elevated the level of phenolic and triterpene acids, while the 10 µM Ag treatment increased the carlina oxide content in the roots. The obtained results indicate an alteration of metabolic pathways of C. acaulis to cope with different levels of Ag(I) stress. Our data imply that the intracellular binding of Ag(I) and nonenzymatic antioxidants contribute to the protection against low concentrations of Ag ions.

16.
Talanta ; 195: 516-524, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30625577

RESUMO

This article presents some aspects of application the dispersive Micro- Raman Spectroscopy in textile fibers analysis. Research were dedicated to the methodology of surface enhancement Raman spectroscopy (SERS) studies on cotton fabric and possibility of its application in fibers characterization. Studies were carried out on dyed cotton fabrics modified by silver nanowires (AgNWs). Three reactive dyes (blue, yellow, red) and four color intensities (0.5%, 1%, 2% and 5%) were used. AgNWs colloid was deposited on undyed and dyed cotton fabrics by dipping and drying method. Dyed fabrics were examined by spectroscopic methods: FTIR ATR, Raman, UV-Vis Diffuse Reflectance Spectroscopy, Fluorescence Spectroscopy. Raman signal enhancement phenomena occurring on the silver nanoparticles increases the possibility of fiber and dye identification especially in the case of dyes used in cotton dyeing reveals fluorescence.

17.
Molecules ; 25(1)2019 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-31905659

RESUMO

The aim of the study was the combination of two measurement methods, the differential scanning calorimetry (DSC) and infrared thermography to evaluate thermal performance of woven and knitted fabrics coated with acrylic pastes containing 20% (P/20) and 40% (P/40) of microcapsules of phase change materials (MPCM) with transition temperatures of 28 °C (MPCM28) and 43 °C (MPCM43). The DSC analysis showed that the phase transition processes for materials modified with pastes P/20 occur in a narrower temperature range than those modified with P/40 pastes. The initial temperatures TOnset (S-S) and TOnset (S-L) are higher for materials modified respectively with pastes P/20 and P/40. The melting and crystallization enthalpy values of both P/20 coated materials are lower by about 45% and 35% compared to P/40. Infrared thermography analysis showed that materials modified with P/20 are heating up faster than modified with P/40 for both MPCM. In the cooling process for modified fabrics the highest temperature decrease was observed in the first 30s. Materials modified with paste P/40 were cooled more slowly in comparison with paste P/20, both for MPCM28 and MPCM43.


Assuntos
Têxteis , Cápsulas , Cristalização , Termodinâmica , Termografia , Temperatura de Transição
18.
Carbohydr Polym ; 177: 397-405, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28962784

RESUMO

A study on the hybrid functionalization of cotton and viscose fabrics using silver nanowires (AgNWs) colloid and titanium dioxide (TiO2) sol prepared in sol-gel technique was carried out. The microwave treatment was applied to change amorphous form of TiO2 to anatase. The photocatalytic activity of both cellulose fabrics was evaluated by decomposition of nicotine using new method on the basis of infrared spectroscopy. The AgNWs/TiO2 modification caused 3 and 4 times (cotton fabric) and 1.8 and 1.5 (viscose fabric) faster decomposition of nicotine under respectively UV and VIS light than for unmodified fabrics. The AgNWs/TiO2 modified cotton showed the surface resistance 1.5×103Ω and antibacterial effect against Staphylococcus aureus and Klebsiella pneumoniae bacteria. The same modification method gives various effects for cotton and viscose fabrics. Our study demonstrates that AgNWs/TiO2 modified cotton fabric with protective properties against bacteria can be used as conductive and air purifying materials.


Assuntos
Antibacterianos/química , Celulose/química , Nanofios/química , Prata , Têxteis , Titânio/química , Klebsiella pneumoniae , Staphylococcus aureus
19.
Toxicol Lett ; 272: 38-48, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-28315385

RESUMO

Some reports indicate that the silver released from dermally applied products containing silver nanoparticles (AgNP) (e.g. wound dressings or cosmetics) can penetrate the skin, particularly if damaged. AgNP were also shown to have cytotoxic and genotoxic activity. In the present study percutaneous absorption of AgNP of two different nominal sizes (Ag15nm or Ag45nm by STEM) and surface modification, i.e. citrate or PEG stabilized nanoparticles, in combination with cosmetic ingredients, i.e. aluminum chloride (AlCl3), methyl paraben (MPB), or di-n-butyl phthalate (DBPH) was assessed using in vitro model based on dermatomed pig skin. The inductively coupled plasma mass spectrometry (ICP-MS) measurements after 24h in receptor fluid indicated low, but detectable silver absorption and no statistically significant differences in the penetration between the 4 types of AgNP studied at 47, 470 or 750µg/ml. Similarly, no significant differences were observed for silver penetration when the AgNP were used in combinations with AlCl3 (500µM), MPB (1250µM) or DBPH (35µM). The measured highest amount of Ag that penetrated was 0.45ng/cm2 (0.365-0.974ng/cm2) for PEG stabilized Ag15nm+MPB.


Assuntos
Cosméticos/farmacologia , Nanopartículas Metálicas/química , Prata/farmacocinética , Absorção Cutânea/efeitos dos fármacos , Pele/efeitos dos fármacos , Cloreto de Alumínio , Compostos de Alumínio/administração & dosagem , Compostos de Alumínio/química , Compostos de Alumínio/farmacologia , Animais , Cloretos/administração & dosagem , Cloretos/química , Cloretos/farmacologia , Cosméticos/administração & dosagem , Cosméticos/química , Dibutilftalato/administração & dosagem , Dibutilftalato/química , Dibutilftalato/farmacologia , Técnicas In Vitro , Espectrometria de Massas , Nanopartículas Metálicas/administração & dosagem , Parabenos/administração & dosagem , Parabenos/química , Parabenos/farmacologia , Tamanho da Partícula , Prata/administração & dosagem , Prata/química , Pele/metabolismo , Propriedades de Superfície , Suínos
20.
Artigo em Inglês | MEDLINE | ID: mdl-27901646

RESUMO

Welding processes that generate fumes containing toxic metals, such as hexavalent chromium (Cr(VI)), manganese (Mn), and nickel (Ni), have been implicated in lung injury, inflammation, and lung tumor promotion in animal models. The principal objective of this study was to determine the dynamics of toxic effects of inhalation exposure to morphologically rated welding dust from stainless steel welding and its soluble form in TSE System with a dynamic airflow. We assessed the pulmonary toxicity of welding dust in Wistar rats exposed to 60.0 mg/m3 of respirable-size welding dust (mean diameter 1.17 µm) for 2 weeks (6 h/day, 5 days/week); the aerosols were generated in the nose-only exposure chambers (NOEC). An additional aim included the study of the effect of betaine supplementation on oxidative deterioration in rat lung during 2 weeks of exposure to welding dust or water-soluble dust form. The animals were divided into eight groups (n = 8 per group): control, dust, betaine, betaine + dust, soluble-form dust, soluble-form dust + betaine, saline and saline + betaine groups. Rats were euthanized 1 or 2 weeks after the last exposure for assessment of pulmonary toxicity. Differential cell counts, total protein concentrations and cellular enzyme (lactate dehydrogenase-LDH) activities were determined in bronchoalveolar lavage (BAL) fluid, and corticosterone and thiobarbituric acid reactive substances (TBARS) concentrations were assessed in serum. The increase in polymorphonuclear (PMN) leukocytes in BAL fluid (a cytological index of inflammatory responses of the lung) is believed to reflect pulmonary toxicity of heavy metals. Biomarkers of toxicity assessed in bronchoalveolar fluids indicate that the level of the toxic effect depends mainly on the solubility of studied metal compounds; biomarkers that showed treatment effects included: total cell, neutrophil and lymphocyte counts, total protein concentrations, and cellular enzyme (lactate dehydrogenase) activity. Betaine supplementation at 250 mg/kg/day in all study rats groups attenuated stress indices, and corticosterone and TBARS serum levels, and simultaneously stimulated increase of polymorphonuclear cells in BALF of rats. The study confirmed deleterious effect of transitory metals and particles during experimental inhalation exposure to welding dusts, evidenced in the lungs and brain by increased levels of total protein, higher cellular influx, rise of LDH in BALF, elevated TBARS and increased corticosterone in serum of rats. Our result confirm also the hypothesis about the effect of the welding dusts on the oxidative stress responsible for disturbed systemic homeostasis and impairment of calcium regulation.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Exposição por Inalação , Aço Inoxidável/toxicidade , Soldagem , Animais , Líquido da Lavagem Broncoalveolar/química , Modelos Animais de Doenças , Poeira , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/patologia , Masculino , Ratos , Ratos Wistar
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