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1.
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.

2.
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.

3.
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.

4.
Membranes (Basel) ; 12(2)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35207072

RESUMO

The influence of various factors on the removal efficiency of selected pharmaceuticals by membrane filtration was investigated. Several commercial polymer membranes were used for nanofiltration (NF) from various manufacturers. The studies were conducted for ibuprofen (IBF), amoxicillin (AMX), diclofenac (DCF), tetracycline (TRC), salicylic acid (SA) and acetylsalicylic acid (ASA). The influence of the structure and properties of the tested compounds on the retention coefficient and filtration rate was investigated. The influence of pH on the filtration parameters was also checked. The properties of selected membranes influencing the retention of pharmaceuticals and filtrate flux were analysed. An extensive analysis of the retention coefficients dependence on the contact angle and surface free energy was performed. It was found that there is a correlation between the hydrophilicity of the membrane and the effectiveness and efficiency of the membrane. As the contact angle of membrane increased, the flow rate of the filtrate stream increased, while the retention coefficient decreased. The studies showed that the best separation efficiency was achieved for compounds with a molecular weight (MW) greater than 300 g/mol. During the filtration of pharmaceuticals with MW ranging from 300 to 450 g/mol, the type of membrane used practically did not affect the filtration efficiency and a high degree of retention was achieved. In the case of low MW molecules (SA and ASA), a significant decrease in the separation efficiency during the process was noted.

5.
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.

6.
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.

7.
Materials (Basel) ; 14(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200740

RESUMO

It was shown that carbon nonwoven fabrics obtained from polyacrylonitrile fibers (PAN) by thermal conversion may be modified on the surface in order to improve their biological compatibility and cellular response, which is particularly important in the regeneration of bone or cartilage tissue. Surface functionalization of carbon nonwovens containing C-C double bonds was carried out using in situ generated diazonium salts derived from aromatic amines containing both electron-acceptor and electron-donor substituents. It was shown that the modification method characteristic for materials containing aromatic structures may be successfully applied to the functionalization of carbon materials. The effectiveness of the surface modification of carbon nonwoven fabrics was confirmed by the FTIR method using an ATR device. The proposed approach allows the incorporation of various functional groups on the nonwovens' surface, which affects the morphology of fibers as well as their physicochemical properties (wettability). The introduction of a carboxyl group on the surface of nonwoven fabrics, in a reaction with 4-aminobenzoic acid, became a starting point for further modifications necessary for the attachment of RGD-type peptides facilitating cell adhesion to the surface of materials. The surface modification reduced the wettability (θ) of the carbon nonwoven by about 50%. The surface free energy (SFE) in the chemically modified and reference nonwovens remained similar, with the surface modification causing an increase in the polar component (ɣp). The modification of the fiber surface was heterogeneous in nature; however, it provided an attractive site of cell-materials interaction by contacting them to the fiber surface, which supports the adhesion process.

8.
Psychoneuroendocrinology ; 127: 105202, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33756285

RESUMO

The development of costly traits such as immune function and secondary sexual traits is constrained by resource availability. The quality of developmental conditions and the availability of resources in ontogeny may therefore influence immune system functions and other biological traits. We analyzed causal pathways between family socioeconomic position, strength of immune response, and five physiological biomarkers in young Latvian men (n = 93) using structural equation modeling. Men from wealthier families had higher testosterone levels (rs = 0.280), stronger immune response (rs = 0.551), and higher facial attractiveness (rs = 0.300). There were weak, non-significant correlations between family income, body fat percentage (rs = -0.147), and fluctuating asymmetry (rs = -0.159). Testosterone partially (33.8%) mediated the effect of family income on facial masculinity. Testosterone (positively) and adiposity (negatively) partially (4%) mediated the relationship between family income and immune function. Higher facial masculinity, higher facial symmetry, and lower adiposity were reliable and independent cues of better immune function (R2 = 0.238) in a larger sample of young Latvian men (N = 146). Resource availability in ontogeny has an important role for the development of immune function and physical appearance, and it is a key parameter to be included in human eco-immunological research.


Assuntos
Imunidade , Classe Social , Biomarcadores/sangue , Humanos , Imunidade/fisiologia , Renda , Masculino , Masculinidade , Testosterona/sangue
9.
Artigo em Inglês | MEDLINE | ID: mdl-33503828

RESUMO

While COVID-19 infection and mortality rates are soaring in Western countries, Southeast Asian countries have successfully avoided the second wave of the SARS-CoV-2 pandemic despite high population density. We provide a biochemical hypothesis for the connection between low COVID-19 incidence, mortality rates, and high visceral adiposity in Southeast Asian populations. The SARS-CoV-2 virus uses angiotensin-converting enzyme 2 (ACE2) as a gateway into the human body. Although the highest expression levels of ACE2 are found in people's visceral adipose tissue in Southeast Asia, this does not necessarily make them vulnerable to COVID-19. Hypothetically, high levels of visceral adiposity cause systemic inflammation, thus decreasing the ACE2 amount on the surface of both visceral adipocytes and alveolar epithelial type 2 cells in the lungs. Extra weight gained during the pandemic is expected to increase visceral adipose tissue in Southeast Asians, further decreasing the ACE2 pool. In contrast, weight gain can increase local inflammation in fat depots in Western people, leading to worse COVID-related outcomes. Because of the biological mechanisms associated with fat accumulation, inflammation, and their differential expression in Southeast Asian and Western populations, the second wave of the pandemic may be more severe in Western countries, while Southeast Asians may benefit from their higher visceral fat depots.


Assuntos
COVID-19/epidemiologia , Gordura Intra-Abdominal/fisiologia , Obesidade/complicações , Pandemias , Adiposidade , Enzima de Conversão de Angiotensina 2 , Sudeste Asiático , Povo Asiático , COVID-19/mortalidade , Humanos , Incidência , Inflamação , Obesidade/epidemiologia , Peptidil Dipeptidase A , População Branca
10.
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
11.
Materials (Basel) ; 13(2)2020 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31940765

RESUMO

Current restrictions on the use of antibiotics, associated with increases in bacterial resistance, require new solutions, including materials with antibacterial properties. In this study, copper alginate fibers obtained using the classic wet method were used to make nonwovens which were modified with arginine-glycine-aspartic acid (RGD) derivatives. Stable polysaccharide-peptide conjugates formed by coupling with 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium toluene-4-sulfonate (DMT/NMM/TosO-), and materials with physically embedded RGD derivatives, were obtained. The materials were found to be characterized by very high antibacterial activity against S. aureus and K. pneumoniae. Cytotoxicity studies confirmed that the materials are not cytotoxic. Copper alginate conjugates with RGD peptides have strong potential for use in regenerative medicine, due to their biocompatibility and innate antibacterial activity.

12.
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
13.
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
14.
Int J Occup Med Environ Health ; 29(4): 667-82, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27443762

RESUMO

OBJECTIVES: Diesel exhaust fumes emission is a significant source of ultrafine particles, the size of which is expressed in nanometers. People occupationally exposed to diesel exhaust particles include mainly workers servicing vehicles with engines of this type. This article presents the analysis of measurements of ultrafine particle concentrations occurring in the bus depot premises during the work connected with everyday technical servicing of buses. MATERIAL AND METHODS: The measurements were carried out in the everyday servicing (ES) room of the bus depot before, during and after the work connected with bus servicing. Determinations included: particle concentrations in terms of particle number and particle surface area, and mass concentrations of aerosol. RESULTS: Mean value of number concentration of 10- to 1000-nm particles increased almost 20-fold, from 7600 particles/cm3 before starting bus servicing procedures to 130 000 particles/cm3 during the bus servicing procedures in the room. During the procedures, the mean surface area concentration of particles potentially deposited in the alveolar (A) region was almost 3 times higher than that of the particles depositing in the tracheo-bronchial (TB) region: 356.46 µm2/cm3 vs. 95.97 µm2/cm3, respectively. The mass concentration of the fraction of particulate matter with aerodynamic diameter 0.02-1 µm (PM1) increased 5-fold during the analyzed procedures and was 0.042 mg/m3 before, and 0.298 mg/m3 while the procedures continued. CONCLUSIONS: At the time when bus servicing procedures continued in the ES room, a very high increase in all parameters of the analyzed particles was observed. The diesel exhaust particles exhibit a very high degree of fragmentation and, while their number is very high and their surface area is very large, their mass concentration is relatively low. The above findings confirm that ultrafine particles found in diesel exhaust fumes may be harmful to the health of the exposed people, and to their respiratory tract in particular.


Assuntos
Exposição Ocupacional/análise , Material Particulado/análise , Emissões de Veículos/análise , Poluição do Ar em Ambientes Fechados/análise , Humanos , Exposição por Inalação/análise , Veículos Automotores , Tamanho da Partícula
15.
Reg Anesth Pain Med ; 28(4): 347-50, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12945031

RESUMO

BACKGROUND AND OBJECTIVES: Intracranial subdural hematoma is a rare but potentially fatal complication of spinal anesthesia (SA). This case is intended to highlight the importance of careful follow-up of patients with a chronic headache that develops after SA. CASE REPORT: A 38-year-old woman underwent saphenous vein ligation for varices under SA. On the first postoperative day, she complained of severe postural headache that was controllable with oral analgesics. Two weeks later, bilateral abducens nerve palsy with diplopia developed. Brain magnetic resonance imaging (MRI) showed small bilateral subdural hygromas. Diplopia and headache (no longer postural) were relieved after administration of dexamethasone, but reappeared 6 wks later. This time, MRI showed large subdural hematomas. The patient was treated with burr-hole decompression. CONCLUSIONS: Persistent headache after SA requires careful neurologic and radiologic follow-up for exclusion of chronic intracranial bleeding. Pharmacologic treatment may mask some neurologic symptoms and delay diagnosis of intracranial complications related to SA.


Assuntos
Raquianestesia/efeitos adversos , Hematoma Subdural Crônico/etiologia , Doenças do Sistema Nervoso/etiologia , Traumatismo do Nervo Abducente/etiologia , Adulto , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Encéfalo/patologia , Doença Crônica , Descompressão Cirúrgica , Dexametasona/administração & dosagem , Dexametasona/uso terapêutico , Diplopia/etiologia , Feminino , Cefaleia/etiologia , Hematoma Subdural Crônico/patologia , Hematoma Subdural Crônico/cirurgia , Humanos , Ligadura , Imageamento por Ressonância Magnética , Doenças do Sistema Nervoso/patologia , Doenças do Sistema Nervoso/cirurgia , Veia Safena
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