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1.
Transfusion ; 64(1): 141-149, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38059437

RESUMO

BACKGROUND: Each unit of red blood cells (RBCs) produced represents a significant cost to the healthcare system. Unnecessary blood wastage should be minimized. In clinical settings, alterations to blood component bags after issue from the protected setting of the blood bank include pen markings, and those that are exposed to an infectious environment require surface disinfecting. These units may be discarded due to unclear effects on RBC quality. In this study, we investigate whether pen markings or surface disinfection negatively affects the quality of packed RBCs and whether pen ink diffuses through the blood bag. STUDY DESIGN AND METHODS: RBC bags were marked with pens (water, oil, or alcohol-based) or subjected to surface disinfection (ethanol, hydrogen peroxide [Preempt wipes], or benzalkonium chloride-based wipes [CaviWipes]) and sampled 24 h after applying the treatment and at day 42 post collection (n = 3 for each condition). The samples were analyzed for RBC in vitro quality markers. The presence of any ink in the RBC bags was investigated using mass spectrometry (n = 2). RESULTS: Data from 24 h and day 42 time points indicated no differences in RBC count, mean corpuscular volume, morphology, deformability, potassium content, or hemolysis for either pen markings or disinfectants when compared with their untreated controls (p > .05). No trace of ink was detected inside the bag. CONCLUSION: RBC units marked with ballpoint, gel, or Sharpie pens do not suffer a loss of in vitro quality, nor do RBC units which have been surface disinfected with 70% ethanol, Preempt wipes or CaviWipes.


Assuntos
Desinfetantes , Humanos , Desinfetantes/farmacologia , Tinta , Preservação de Sangue/métodos , Eritrócitos , Cloreto de Polivinila/química , Cloreto de Polivinila/farmacologia , Etanol/farmacologia , Compostos Orgânicos
2.
J Water Health ; 20(8): 1256-1267, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36044193

RESUMO

Di-(2-ethylhexyl) phthalate (DEHP) is the world's most widely used polyvinyl chloride (PVC) plasticizer and is used in virtually every category of flexible PVC. In fact, DEHP is extensively used in food cosmetics and medical packaging. It has become a serious problem in recent years. DEHP can be absorbed into the human body through the air, food, water, and skin. The current study involved intraperitoneal injection of DEHP dissolved in corn oil once daily for 21 consecutive days to investigate the effects of DEHP on the thyroid and the reproductive system in female rats. Results show that ovarian hormones (progesterone and estrogen) decreased significantly in the rats treated with DEHP compared to control. This result is supported by the alteration of folliculogenesis, the decrease of the follicles viability, and the apoptosis of the granulosa cells observed on histological sections of ovary and thyroid in female rats exposed to low doses of DEHP. Histopathological study revealed that DEHP could damage thyroid tissue and disrupt these functions. We also observed cellular damage, particularly in the liver cells, and a significant increase in biochemical parameters such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST) compared to the control group.


Assuntos
Dietilexilftalato , Disruptores Endócrinos , Adulto , Animais , Dietilexilftalato/toxicidade , Disruptores Endócrinos/toxicidade , Feminino , Humanos , Ovário , Ácidos Ftálicos , Cloreto de Polivinila/farmacologia , Ratos , Glândula Tireoide
3.
Food Microbiol ; 106: 104054, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35690447

RESUMO

Human pathogens can develop biofilm structures on different artificial substrates common in the food industry. In this study, we investigated the inactivation efficacy of low-energy X-ray irradiation on Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes biofilms on food contact surfaces, including polyvinyl chloride (PVC), stainless steel with finish 2B (STS 2B), and Teflon. The numbers of viable cells in biofilms on all test coupons were significantly (p < 0.05) reduced as the X-ray dose increased. Interestingly, different biofilm inactivation levels were observed relative to various material surfaces. Teflon showed the lowest D5d (dose required for a 5-log reduction in cell count) values among three groups of coupons, whereas PVC exhibited higher D5d values than the other two coupons. The mechanism of the X-ray antibiofilm effect was identified through the measurement of extracellular polymeric substances (EPS) in biofilms. X-ray irradiation could remove exopolysaccharides, which are major component of EPS and the removal rate increased with increasing irradiation dose. The analyses also confirmed that the disintegration of EPS was strongly related to the trends of biofilm inactivation on different coupon surfaces. This study is the first to demonstrate that X-ray irradiation effectively inactivates major foodborne pathogen biofilms on various food contact surfaces and to evaluate its antibiofilm mechanisms to enhance safety in the food processing industries.


Assuntos
Microbiologia de Alimentos , Listeria monocytogenes , Biofilmes , Contagem de Colônia Microbiana , Humanos , Politetrafluoretileno/farmacologia , Cloreto de Polivinila/farmacologia , Aço Inoxidável , Raios X
4.
Chem Res Toxicol ; 34(6): 1468-1480, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-33861932

RESUMO

High concentrations of micro- and nanoparticles of common plastic materials present in the environment are causing an adverse health impact on living organisms. As a model study, here we report the synthesis and characterization of luminescent polyvinyl chloride (PVC) and poly(methyl methacrylate) (PMMA) nanoparticles and investigate the interaction with normal human lung fibroblast cells (IMR 90) to understand the uptake, translocation, and toxicity of PVC and PMMA nanoparticles. The synthesized particles are in the size range of 120-140 nm with a negative surface potential. The colocalization and uptake efficiency of the nanoparticles were analyzed, and the cytotoxicity assay shows significant reduction in cell viability. Cellular internalization was investigated using colocalization and dynasore inhibitor tests, which showed that the PVC and PMMA nanoparticles enter into the cell via endocytosis. The polymer nanoparticles induced a reduction in viability, decrease in adenosine triphosphate, and increase in reactive oxygen species and lactate dehydrogenase concentrations. In addition, the polymer nanoparticles caused cell cycle arrest at sub-G1, G0/G1, and G2/M phases, followed by apoptotic cell death. Our results reported here are important to the emerging data on understanding the impact of common polymer particles on human health.


Assuntos
Nanopartículas/química , Polimetil Metacrilato/farmacologia , Cloreto de Polivinila/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Tamanho da Partícula
5.
Bull Environ Contam Toxicol ; 104(3): 315-320, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31960073

RESUMO

Microplastics have become a global concern in recent years. In this study, we studied (i) whether the presence of polyvinyl chloride (PVC) microparticles may affect cadmium (Cd) uptake in mussel (Mytilus edulis); and (ii) the biological effects of PVC microparticles exposure alone or in combination with Cd. Significant Cd uptake in digestive gland was observed following Cd exposure. However, PVC did not significantly increase Cd uptake compared with Cd alone treatment. In terms of biological impacts, significantly lower neutral red retention (NRR) time and elevated expression of Metallothionein isoform 20-IV (MT-20) were observed in mussels exposed to Cd alone, or combined with microplastics, yet there was no significant difference between them. catalase (CAT) expression only showed a significant increase in mussels exposed to Cd alone. This work provides an insight into the relationship on resulting biological impacts between these two contaminants.


Assuntos
Cádmio/metabolismo , Mytilus edulis/metabolismo , Cloreto de Polivinila/farmacologia , Animais , Catalase/metabolismo , Metalotioneína/metabolismo , Mytilus/metabolismo , Alimentos Marinhos , Poluentes Químicos da Água/metabolismo
6.
J Appl Microbiol ; 125(4): 1030-1039, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29742310

RESUMO

AIMS: Four commercially available robotic vacuum cleaners were assessed for sampling efficiency of wet disseminated Bacillus atrophaeus spores on carpet, polyvinyl chloride (PVC) and laminate flooring. Furthermore, their operability was evaluated and decontamination efficiency of one robot was assessed, using a sodium hypochlorite solution. METHODS AND RESULTS: In an environmental chamber, robots self-navigated around 4 m2 of flooring containing a single contaminated 0·25 m2 tile (c. 104 spores per cm2 ). Contamination levels at predetermined locations were assessed by macrofoam swabs (PVC and laminate) or water soluble tape (carpet), before and after sampling. Robots were dismantled postsampling and spore recoveries assessed. Aerosol contamination was also measured during sampling. Robot sampling efficiencies were variable, however, robots recovered most spores from laminate (up to 17·1%), then PVC and lastly the carpet. All robots spread contamination from the 'hotspot' (all robots spread <0·6% of the contamination to other areas) and became surface contaminated. Spores were detected at low levels during air sampling (<5·6 spores per litre). Liquid decontamination inactivated 99·1% of spores from PVC. CONCLUSIONS: Robotic vacuum cleaners show promise for both sampling and initial decontamination of indoor flooring. SIGNIFICANCE AND IMPACT OF THE STUDY: In the event of a bioterror incident, e.g. deliberate release of Bacillus anthracis spores, areas require sampling to determine the magnitude and extent of contamination, and to establish decontamination efficacy. In this study, we investigate robotic sampling methods against high concentrations of bacterial spores applied by wet deposition to different floorings, contamination spread to other areas, potential transfer of spores to the operators and assessment of a wet vacuum robot for spore inactivation. The robots' usability was evaluated and how they can be employed in real life scenarios. This will help to reduce the economic cost of sampling and the risk to sampling/decontamination teams.


Assuntos
Bacillus/crescimento & desenvolvimento , Descontaminação/métodos , Utensílios Domésticos/instrumentação , Esporos Bacterianos/crescimento & desenvolvimento , Aerossóis/análise , Automação/instrumentação , Bacillus/classificação , Bacillus/efeitos dos fármacos , Bacillus anthracis , Habitação/estatística & dados numéricos , Cloreto de Polivinila/farmacologia , Procedimentos Cirúrgicos Robóticos , Robótica/instrumentação , Hipoclorito de Sódio/farmacologia , Manejo de Espécimes , Esporos Bacterianos/classificação , Esporos Bacterianos/efeitos dos fármacos , Vácuo
7.
Vox Sang ; 110(3): 227-35, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26646434

RESUMO

BACKGROUND AND OBJECTIVES: Di-2-ethylhexyl phthalate (DEHP) is a blood bag plasticizer. It is also a toxin, raising concerns for vulnerable populations, for example, neonates and infants. Here, the in vitro quality of red cell concentrates (RCC) stored in paediatric bags formulated with alternative plasticizers to DEHP was compared. MATERIALS AND METHODS: RCC were pooled and split into polyvinylchloride (PVC)/DEHP, PVC/1,2-cyclohexanedicarboxylic acid diisononyl ester (DINCH) or PVC/butyryl trihexyl citrate (BTHC) bags. Quality was assessed on storage days 5, 21, 35 and 43. RESULTS: Metabolism differed among the bags: pCO2 levels were lowest and pO2 were highest in BTHC bags. Glucose consumption and lactate production suggested higher metabolic rates in BTHC bags. ATP levels were best maintained in DINCH bags (day 43 mean level: 2·86 ± 0·29 µmol/g Hb). RCC in BTHC bags had the greatest potassium release (54·6 ± 3·0 mm on day 43). From day 21, haemolysis was higher in BTHC bags (P < 0·01) and by day 43 had exceeded 0·8% (0·85 ± 0·10%). RCC in BTHC bags showed more microparticle formation than RCC in DEHP or DINCH bags. CONCLUSION: The results suggest that the BTHC formulation used was detrimental to RBC quality. DINCH bags could be a viable alternative to DEHP: they outperformed DEHP bags energetically, with better maintenance of ATP levels.


Assuntos
Preservação de Sangue/métodos , Dietilexilftalato/química , Eritrócitos/metabolismo , Plastificantes/química , Cloreto de Polivinila/química , Trifosfato de Adenosina/análise , Contagem de Células Sanguíneas , Gasometria , Preservação de Sangue/instrumentação , Dietilexilftalato/farmacologia , Eritrócitos/efeitos dos fármacos , Glucose/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Lactente , Recém-Nascido , Ácido Láctico/metabolismo , Plastificantes/farmacologia , Cloreto de Polivinila/farmacologia , Potássio/análise , Potássio/metabolismo , Temperatura , Fatores de Tempo
8.
Appl Environ Microbiol ; 80(16): 4821-31, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24907329

RESUMO

When immersed in seawater, substrates are rapidly colonized by both micro- and macroorganisms. This process is responsible for important economic and ecological prejudices, particularly when related to ship hulls or aquaculture nets. Commercial antifouling coatings are supposed to reduce biofouling, i.e., micro- and macrofoulers. In this study, biofilms that primarily settled on seven different coatings (polyvinyl chloride [PVC], a fouling release coating [FRC], and five self-polishing copolymer coatings [SPC], including four commercial ones) were quantitatively studied, after 1 month of immersion in summer in the Toulon Bay (Northwestern Mediterranean Sea, France), by using flow cytometry (FCM), microscopy, and denaturing gradient gel electrophoresis. FCM was used after a pretreatment to separate cells from the biofilm matrix, in order to determine densities of heterotrophic bacteria, picocyanobacteria, and pico- and nanoeukaryotes on these coatings. Among diatoms, the only microphytobenthic class identified by microscopy, Licmophora, Navicula, and Nitzschia were determined to be the dominant taxa. Overall, biocide-free coatings showed higher densities than all other coatings, except for one biocidal coating, whatever the group of microorganisms. Heterotrophic bacteria always showed the highest densities, and diatoms showed the lowest, but the relative abundances of these groups varied depending on the coating. In particular, the copper-free SPC failed to prevent diatom settlement, whereas the pyrithione-free SPC exhibited high picocyanobacterial density. These results highlight the interest in FCM for antifouling coating assessment as well as specific selection among microbial communities by antifouling coatings.


Assuntos
Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , Diatomáceas/fisiologia , Polímeros/farmacologia , Água do Mar/microbiologia , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Diatomáceas/classificação , Diatomáceas/efeitos dos fármacos , Diatomáceas/isolamento & purificação , Mar Mediterrâneo , Cloreto de Polivinila/farmacologia , Navios
9.
Biofouling ; 30(8): 965-73, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25237773

RESUMO

Due to their susceptibility to bacterial biofilm formation, commercial tubes for medical use are one of the main sources of hospital infections with Acinetobacter baumannii. The anti-biofouling activity of novel composites against the clinical isolate of the multi-drug resistant A. baumannii is reported here. The composites were prepared by addition of micronised silver-exchanged natural zeolite (Ag-NZ) into poly(vinyl chloride) (PVC), followed by coating of the composites with D-Tyrosine (D-Tyr). The Ag-NZ composites (containing 1-15 wt% of Ag-NZ) coated with D-Tyr (Ag-NZ-Tyr) showed a bactericidal effect (100% or a 6.9 log CFU reduction) towards immobilised bacterial cells. The uncoated Ag-NZ composites showed a reduction of up to 70% (4.4 log CFU) of immobilised bacteria in comparison with the original PVC. Rheological testing of the composites revealed that the addition of Ag-NZ slightly affected processability and formability of the PVC and increased the elasticity of the polymer matrix.


Assuntos
Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/fisiologia , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/classificação , Croácia , Humanos , Testes de Sensibilidade Microbiana , Cloreto de Polivinila/farmacologia , Prata/farmacologia , Tirosina/farmacologia , Zeolitas/farmacologia
10.
J Mater Sci Mater Med ; 25(9): 2049-57, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24893861

RESUMO

Polyvinylidene chloride (PVDC) is a long chain carbon synthetic polymer. The objective of this study was to improve the bioactivity of PVDC films through surface modification using argon (Ar) ion bombardment to create Ar-modified PVDC films (Ar-PVDC) to address the clinical problems of guided bone regeneration (GBR), which is technique-sensitive, and low bone regenerative ability. First, the effects of Ar ion bombardment, a low temperature plasma etching technique widely used in industry, on PVDC film wettability, surface chemistry, and morphology were confirmed. Next, fibroblast-like and osteoblast-like cell attachment and proliferation on Ar-PVDC were assessed. As a preclinical in vivo study, Ar-PVDC was used to cover a critical-sized bone defect on rat calvaria and osteoconductivity was evaluated by micro-computed tomography analysis and histological examinations. We found that the contact angle of PVDC film decreased by 50° because of the production of -OH groups on the PVDC film surface, though surface morphological was unchanged at 30 min after Ar ion bombardment. We demonstrated that cell attachment increased by about 40% and proliferation by more than 140% because of increased wettability, and 2.4 times greater bone regeneration was observed at week 3 with Ar-PVDC compared with untreated PVDC films. These results suggest that Ar ion bombardment modification of PVDC surfaces improves osteoconductivity, indicating its potential to increase bone deposition during GBR.


Assuntos
Argônio , Regeneração Óssea , Cloreto de Polivinila/análogos & derivados , Proliferação de Células , Cloreto de Polivinila/farmacologia , Propriedades de Superfície , Molhabilidade , Microtomografia por Raio-X
11.
J Hosp Infect ; 149: 1-13, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38734184

RESUMO

BACKGROUND: Standardized efficacy surface tests for disinfectants are performed on pristine surfaces. There is a growing interest in understanding the impact of surface ageing on disinfectant activity, owing for example to the increased usage of ultraviolet (UV) radiation and oxidative chemistries for surface decontamination. This acknowledges that general surface 'wear and tear' following UV radiation and oxidative biocide exposure may impact biocidal product efficacy. METHODS: PVC surfaces were aged through thermal and UV-A radiation (340 nm wavelength) following the use of standard ageing surface protocols to simulate natural surface degradation. Surface roughness, contact angle and scanning electron microscopy were performed to evaluate physical changes in PVC surfaces before and after artificial ageing. The efficacy of five pre-impregnated disinfectant wipes were evaluated using the ASTM E2967-15 on stainless-steel (control) and PVC surfaces (aged and non-aged). RESULTS: The type of formulation and the organism tested remained the most significant factors impacting disinfectant efficacy, compared with surface type. Both thermal ageing and UV-A exposure of PVC surfaces clearly showed signs of surface degradation, notably an increase in surface roughness. Physical changes were observed in the roughness of PVC after artificial ageing. A difference in disinfectant efficacy dependent on aged PVC surfaces was observed for some, but not all formulations. CONCLUSION: We showed that surface type and surface ageing can affect biocidal product efficacy, although in a non-predictable manner. More research is needed in this field to ascertain whether surface types and aged surfaces should be used in standardized efficacy testing.


Assuntos
Desinfetantes , Desinfecção , Cloreto de Polivinila , Propriedades de Superfície , Raios Ultravioleta , Desinfetantes/farmacologia , Cloreto de Polivinila/farmacologia , Desinfecção/métodos , Microscopia Eletrônica de Varredura , Fatores de Tempo , Humanos
12.
J Mater Sci Mater Med ; 24(8): 1985-92, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23686353

RESUMO

This paper reports the results of an in vitro investigation into the blood response of medical grade poly (vinyl chloride) (PVC), and two types of plasticized PVC in tubing or sheet form, with di-(2-ethylhexyl)phthalate (DEHP) and di(isononyl) cyclohexane-1,2-dicarboxylate (HEXAMOLL(®) DINCH) as plasticizer, were selected for assessment of complement activation, coagulation system and platelet activation. The results of the study show that not only the plasticizers at PVC surface have an influence on complement activation, but also the incubation condition such as incubation time and the diameter of PVC tubing. Under static status, C3a, C5a and SC5b-9 concentration in the blood were higher after contacting with PVC plasticized with DEHP (PVC1) than after contacting with PVC plasticized with DINCH (PVC2). However, under dynamic circulation, the results were totally converse, which may be due to smaller diameter and higher shear rate of PVC2. In addition, there was a significant increase of activated partial thrombin time (APTT) and decrease of FIX concentration after plasma contacting with the PVC tubing, which indicated that the intrinsic pathway may be impacted when blood contacted with PVC tubing. However, there was no significant difference of APTT, FIX concentration and CD62p expression rate between the two materials. Moreover, the migration in the DINCH system was considerably lower than for DEHP, which indicates that DINCH could be a promising alterative plasticizer of DEHP.


Assuntos
Teste de Materiais , Plastificantes/farmacologia , Cloreto de Polivinila/química , Cloreto de Polivinila/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Ativação do Complemento/efeitos dos fármacos , Complemento C3a/metabolismo , Dietilexilftalato/farmacologia , Humanos , Modelos Biológicos , Selectina-P/metabolismo , Ativação Plaquetária/efeitos dos fármacos , Plasma Rico em Plaquetas/efeitos dos fármacos , Plasma Rico em Plaquetas/metabolismo , Propriedades de Superfície/efeitos dos fármacos , Molhabilidade/efeitos dos fármacos
13.
World J Microbiol Biotechnol ; 29(7): 1197-206, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23397109

RESUMO

Disease-causing bacteria of the genus Aeromonas are able to adhere to pipe materials, colonizing the surfaces and forming biofilms in water distribution systems. The aim of our research was to study how the modification of materials used commonly in the water industry can reduce bacterial cell attachment. Polyvinyl chloride and silicone elastomer surfaces were activated and modified with reactive organo-silanes by coupling or co-crosslinking silanes with the native material. Both the native and modified surfaces were tested using the bacterial strain Aeromonas hydrophila, which was isolated from the Polish water distribution system. The surface tension of both the native and modified surfaces was measured. To determine cell viability and bacterial adhesion two methods were used, namely plate count and luminometry. Results were expressed in colony-forming units (c.f.u.) and in relative light units (RLU) per cm(2). Almost all the chemically modified surfaces exhibited higher anti-adhesive and anti-microbial properties in comparison to the native surfaces. Among the modifying agents examined, poly[dimethylsiloxane-co-(N,N-dimethyl-N-n-octylammoniopropyl chloride) methylsiloxane)] terminated with hydroxydimethylsilyl groups (20 %) in silicone elastomer gave the most desirable results. The surface tension of this modifier, was comparable to the non-polar native surface. However, almost half of this value was due to the result of polar forces. In this case, in an adhesion analysis, only 1 RLU cm(-2) and less than 1 c.f.u. cm(-2) were noted. For the native gumosil, the results were 9,375 RLU cm(-2) and 2.5 × 10(8) c.f.u. cm(-2), respectively. The antibacterial activity of active organo-silanes was associated only with the carrier surface because no antibacterial compounds were detected in liquid culture media, in concentrations that were able to inhibit cell growth.


Assuntos
Aeromonas hydrophila/efeitos dos fármacos , Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Cloreto de Polivinila/química , Cloreto de Polivinila/farmacologia , Elastômeros de Silicone/química , Elastômeros de Silicone/farmacologia , Aeromonas hydrophila/isolamento & purificação , Aeromonas hydrophila/fisiologia , Biofilmes/efeitos dos fármacos , Contagem de Colônia Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Polônia , Microbiologia da Água
14.
Mar Environ Res ; 176: 105605, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35316651

RESUMO

In an attempt to ensure that bioplastics, progressively replacing petrochemical-derived plastics, do not release any harmful compound to the environment, the study assessed the toxic effects of three innovative bioplastic products: polyhydroxybutyrate resin (PHB), polylactic acid cups (PLA) and a polylactic acid/polyhydroxyalkanoate 3D printing filament (PLA/PHA), together with a synthetic polyvinyl chloride (PVC) toy in Paracentrotus lividus sea urchin larvae. PVC toy was the most toxic material, likely due to the added plasticizers; remarkably, even if PHB is conceived as a nontoxic polymer, it showed a slight toxicity and Gas Chromatography-Mass Spectometry analysis (GC-MS) revealed the presence of a wide range of additives. Conversely, PLA cups and PLA/PHA filament were innocuous for the larvae, a positive outcome for these renewable solutions. Proven that additives are also used in some bioplastic formulations, they should be carefully addressed to ensure that they are as safe as regarded.


Assuntos
Paracentrotus , Poluentes Químicos da Água , Animais , Larva , Poliésteres/toxicidade , Cloreto de Polivinila/farmacologia , Poluentes Químicos da Água/análise
15.
J Exp Zool A Ecol Integr Physiol ; 337(2): 181-190, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34762360

RESUMO

The present study aimed at assessing the singular and combined effects of water copper and polyvinyl chloride microplastic (MPVC) on intestinal copper accumulation, histopathological damage, and stress-/immune-related genes' expression in common carp, Cyprinus carpio. Four groups of fish were maintained in triplicate: control (kept in clean water), Cu (exposed to 0.25 mg/L of copper), MPVC (exposed to 0.5 mg/L of MPVC), and Cu-MPVC (exposed to 0.25 mg/L of copper + 0.5 mg/L of MPVC). After 14-day exposure, the fish of Cu and Cu-MPVC treatments exhibited significantly higher intestinal copper contents, compared to the fish of control and MPVC treatments. In this regard, the Cu-MPVC fish had significantly higher copper content than the Cu fish. Exposure to copper and/or MPVC significantly upregulated the intestinal heat shock protein 70 (hsp70), cytochrome P450 family 1 subfamily A member 1 (cyp1a1), lysozyme (lys), defensin (def), mucin 2 (muc2), and mucin 5 (muc5) expression. The highest expression of hsp70, cyp1a1, lys, and def was related to Cu-MPVC treatment; whereas, the highest expression of muc2 and muc5 was observed in Cu and MPVC treatments. Exposure to copper and/or MPVC induced intestinal damage, which Cu-MPVC fish exhibited the highest severity. The present study revealed that exposure to copper and/or MPVC causes intestinal histopathological damage and upregulation in stress- and immune-related genes' expression. The most serious effects were observed in Cu-MPVC treatment that might be due to additive effects of copper and MPVC and/or higher copper accumulation in this treatment.


Assuntos
Carpas , Poluentes Químicos da Água , Animais , Carpas/genética , Carpas/metabolismo , Cobre/metabolismo , Citocromo P-450 CYP1A1/farmacologia , Intestinos , Plásticos/farmacologia , Cloreto de Polivinila/farmacologia , Água , Poluentes Químicos da Água/toxicidade
16.
J Environ Sci (China) ; 23(4): 529-36, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21793392

RESUMO

Cleaning of hollow-fibre polyvinyl chloride (PVC) membrane with different chemical reagents after ultrafiltration of algal-rich water was investigated. Among the tested cleaning reagents (NaOH, HCl, EDTA, and NaClO), 100 mg/L NaClO exhibited the best performance (88.4% +/- 1.1%) in removing the irreversible fouling resistance. This might be attributed to the fact that NaClO could eliminate almost all the major foulants such as carbohydrate-like and protein-like materials on the membrane surface, as confirmed by Fourier transform infrared spectroscopy analysis. However, negligible irreversible resistance (1.5% +/- 1.0%) was obtained when the membrane was cleaning by 500 mg/L NaOH for 1.0 hr, although the NaOH solution could also desorb a portion of the major foulants from the fouled PVC membrane. Scanning electronic microscopy and atomic force microscopy analyses demonstrated that 500 mg/L NaOH could change the structure of the residual foulants on the membrane, making them more tightly attached to the membrane surface. This phenomenon might be responsible for the negligible membrane permeability restoration after NaOH cleaning. On the other hand, the microscopic analyses reflected that NaClO could effectively remove the foulants accumulated on the membrane surface.


Assuntos
Incrustação Biológica/prevenção & controle , Eucariotos/crescimento & desenvolvimento , Membranas Artificiais , Cloreto de Polivinila/química , Ultrafiltração/métodos , Purificação da Água/métodos , Água/parasitologia , Eucariotos/efeitos dos fármacos , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Compostos Orgânicos/análise , Cloreto de Polivinila/farmacologia , Cloreto de Sódio/farmacologia , Hipoclorito de Sódio/farmacologia , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície/efeitos dos fármacos
17.
ACS Appl Mater Interfaces ; 13(27): 32251-32262, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34181389

RESUMO

Poly(vinyl chloride) (PVC) is the most used biomedical polymer worldwide. PVC is a stable and chemically inert polymer. However, microorganisms can colonize PVC producing biomedical device-associated infections. While surface modifications of PVC can help improve the antimicrobial and antiviral properties, the chemically inert nature of PVC makes those modifications challenging and potentially toxic. In this work, we modified the PVC surface using a derivative riboflavin molecule that was chemically tethered to a plasma-treated PVC surface. Upon a low dosage of blue light, the riboflavin tethered to the PVC surface became photochemically activated, allowing for Pseudomonas aeruginosa bacterial biofilm and lentiviral in situ eradication.


Assuntos
Biofilmes/efeitos dos fármacos , Luz , Viabilidade Microbiana/efeitos dos fármacos , Cloreto de Polivinila/química , Cloreto de Polivinila/farmacologia , Riboflavina/química , Inativação de Vírus/efeitos dos fármacos , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Fenômenos Fisiológicos Bacterianos/efeitos da radiação , Biofilmes/efeitos da radiação , Viabilidade Microbiana/efeitos da radiação , Inativação de Vírus/efeitos da radiação
18.
Molecules ; 15(2): 1007-27, 2010 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-20335959

RESUMO

Medical-grade polyvinyl chloride was coated by polysaccharides through a novel physicochemical approach. An initial surface activation was performed foremost via diffuse coplanar surface barrier discharge plasma in air at ambient temperature and pressure. Then, radical graft copolymerization of acrylic acid through grafting-from pathway was directed to render a well-defined brush of high density, and finally a chitosan monolayer and chitosan/pectin alternating multilayer were bound onto the functionalized surfaces. Surface characteristics were systematically investigated using several probe techniques. In vitro bacterial adhesion and biofilm formation assays indicated that a single chitosan layer was incapable of hindering the adhesion of a Staphylococcus aureus bacterial strain, while up to 30% reduction was achieved by the chitosan/pectin layered assembly. On the other hand, chitosan and chitosan/pectin multilayer could retard Escherichia coli adhesion by 50% and 20%, respectively. Furthermore, plasma treated and graft copolymerized samples were also found effective to diminish the degree of adherence of Escherichia coli.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Polissacarídeos/farmacologia , Cloreto de Polivinila/farmacologia , Absorção/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Escherichia coli/citologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Microscopia Eletrônica de Varredura , Modelos Moleculares , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/citologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Água , Molhabilidade/efeitos dos fármacos
19.
Food Sci Technol Int ; 16(3): 225-32, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21339138

RESUMO

Nanoparticles of ZnO and their application in coating systems have attracted a great deal of attention in recent years because of its multifunction property, especially antibacterial activity. In this study, antibacterial and physical properties of poly(vinyl chloride) (PVC) based film coated with ZnO nanoparticles were investigated. It was found that the antibacterial action should be attributed to the killing effect property of ZnO nanoparticles. The ZnO-coated films treated by shaking for 10 h exhibited a similar high antibacterial activity against Escherichia coli and Staphylococcus aureus as the untreated ZnO-coated films. This result indicated that the ZnO nanoparticles adhered very well to the plastic film. The antibacterial activity of the ZnO-coated film to inactivate E. coli or S. aureus was improved by UV irradiation. The analysis of physical properties of the ZnO-coated films revealed that the nano-ZnO particles showed less effects on the tensile strength and elongation at break of the film. The ultraviolet (UV) light fastness of the ZnO-coated PVC film was improved, which may be attributed to the absorption of ZnO nanoparticles against UV light. Water vapor transmission of the ZnO-coated film decreased from 128 to 85 g/m(2) · 24 h, whereas the thickness of film increased from 6.0 µm with increasing the amount of nano-ZnO particles coated from 0 to 187.5 µg/cm(2). This research revealed that the PVC film coated with nano-ZnO particles has a good potential to be used as an active coating system for food packaging.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Nanopartículas/química , Cloreto de Polivinila/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Óxido de Zinco/farmacologia , Antibacterianos/química , Embalagem de Alimentos , Cloreto de Polivinila/química , Óxido de Zinco/química
20.
Eksp Klin Gastroenterol ; (2): 58-64, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19552022

RESUMO

Nanostructured materials with various methods of coating have antimicrobial activity and can be used in creation of biologically active systems with a given medical-biological characteristics. Use of organic derivatives of fullerene S60 as a new class of biologically active compounds and their use is a new and promising direction in this area, providing a selective effect on the micro-organisms of different species. Using probes with the biologically active nanostructured surfaces useful for the correction of pH-dependent states, such as the translocation of microflora in the intestine when postgastrectomical states may have to correct with GERD. Programmable output regulators of activity of intestinal microbiota can be viewed as a way of normalizing the digestive-transport processes in the intestine.


Assuntos
Quitosana/química , Nutrição Enteral/instrumentação , Fulerenos/química , Nanoestruturas/química , Polietilenotereftalatos/química , Cloreto de Polivinila/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Biofilmes/crescimento & desenvolvimento , Quitosana/farmacologia , Equipamentos Descartáveis/microbiologia , Equipamentos Descartáveis/normas , Fulerenos/farmacologia , Suco Gástrico/química , Teste de Materiais , Nanoestruturas/normas , Polietilenotereftalatos/farmacologia , Cloreto de Polivinila/farmacologia , Propriedades de Superfície
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