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1.
Am J Disaster Med ; 16(1): 67-73, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33954977

RESUMEN

BACKGROUND: Chemical, biological, radiologic, nuclear, and explosive (CBRNE) events threaten the health and integrity of human populations across the globe. Effective decontamination is a central component of CBRNE disaster response. OBJECTIVE: This paper provides an objective determination of wet decontamination effectiveness through the use of a liquid-based contaminant proxy and describes the mobilization and adaptation of easily available materials for the needs of decontamination in pediatric victims. METHODS: In this in-situ disaster simulation conducted at a pediatric hospital, decontamination effectiveness was determined through a liquid-based contaminant proxy, and standard burn charts to systematically estimate affected total body surface area (TBSA) in 39 adult simulated patients. Two independent raters evaluated TBSA covered by the contaminant before and after decontamination. RESULTS: On average, simulated patients had 59 percent (95 percent CI [53, 65]) of their TBSA covered by the simulated contaminant prior to decontamination. Following a wet decontamination protocol, the average reduction in TBSA contamination was 81 percent (95 percent CI [74, 88]). There was high inter-rater reliability for TBSA assessment (intraclass correlation coefficient = 0.83, 95 percent CI [0.68, 0.92]. A modified infant bath was tested during the simulated decontamination of infant mannequins and thereafter integrated to the local protocol. CONCLUSION: Wet decontamination can remove more than 80 percent of the initial contaminant found on adult simulated patients. The use of a liquid-based visual tool as a contaminant proxy enables the inexpensive evaluation of decontamination performance in a simulated setting. This paper also describes an innovative, low-cost adaptation of a local decontamination protocol to better meet pediatric needs.


Asunto(s)
Quemaduras , Planificación en Desastres , Desastres , Adulto , Niño , Descontaminación , Humanos , Lactante , Reproducibilidad de los Resultados
2.
Bioresour Technol ; 332: 125121, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33845314

RESUMEN

Currently, there is a lack of an efficient, environmentally-benign and sustainable industrial decontamination strategy to steadily achieve improved astaxanthin production from Haematococcus pluvialis under large-scale outdoor conditions. Here, this study demonstrates for the first time that a CaCO3 biomineralization-based decontamination strategy (CBDS) is highly efficient in selectively eliminating algicidal microorganisms, such as bacteria and fungi, during large-scale H. pluvialis cultivation under autotrophic and mixotrophic conditions, thereby augmenting the astaxanthin productivity. Under outdoor AT and MT conditions, the average astaxanthin productivity of H. pluvialis using CBDS in a closed photobioreactor system was substantially increased by 14.85- (1.19 mg L-1 d-1) and 13.65-fold (2.43 mg L-1 d-1), respectively, compared to the contaminated H. pluvialis cultures. Given the exponentially increasing demand of astaxanthin, a natural anti-viral, anti-inflammatory, and antioxidant drug, CBDS will be a technology of interest in H. pluvialis-based commercial astaxanthin production which has been hindered by the serious biological contaminations.


Asunto(s)
Chlorophyta , Biomasa , Biomineralización , Descontaminación , Xantófilas
3.
Water Sci Technol ; 83(7): 1662-1676, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33843750

RESUMEN

In the present study, adsorption of colour and other pollutants from agro-based paper mill effluent onto fabricated coal fly ash nanoparticles (CFA-N) have been investigated. Response surface methodology was applied to evaluate the operational conditions for maximum ouster of colour from effluent by nano structured CFA-N. Maximum reduction in colour (92.45%) and other pollutants were obtained at optimum conditions: 60 min interaction time, 60 g/L adsorbent dosage and 80 rpm agitation rate. The regression coefficient values (adjusted R2 = 0.7169; predicted R2 = 0.7539) established harmony between predicted and the experimental data. The adsorption equilibrium results matched perfectly with both Langmuir and Freundlich isotherms with maximum adsorption capacity of 250 platinum-cobalt/g. Additionally, the efficacy of CFA-N was also assessed in a continuous column mode. Furthermore, the feasibility of treated effluent for irrigation purpose was checked by growing the plant Solanum lycopersicum. Overall, the findings demonstrated the outstanding role of inexpensive and abundantly available CFA-N in treatment of paper mill effluent to the required compliance levels.


Asunto(s)
Ceniza del Carbón , Contaminantes Químicos del Agua , Adsorción , Carbón Mineral , Descontaminación , Concentración de Iones de Hidrógeno , Cinética , Contaminantes Químicos del Agua/análisis
4.
Artículo en Inglés | MEDLINE | ID: mdl-33802722

RESUMEN

Planning for major incidents involving the release of hazardous chemicals has been informed by a multi-disciplinary research agenda which has sought to inform all aspects of emergency response, but with a focus in recent years on mass casualty decontamination. In vitro and human volunteer studies have established the relative effectiveness of different decontamination protocols for a range of chemical agents. In parallel, a programme of research has focused on communicating with and managing large numbers of contaminated casualties at the scene of an incident. We present an accessible overview of the evidence underpinning current casualty decontamination strategies. We highlight where research outcomes can directly inform response planning, including the critical importance of beginning the decontamination process as soon as possible, the benefits of early removal of contaminated clothing, the evidence under-pinning dry and wet decontamination and how effective communication is essential to any decontamination response. We identify a range of priority areas for future research including establishing the significance of the 'wash-in' effect and developing effective strategies for the decontamination of hair. We also highlight several areas of future methodological development, such as the need for novel chemical simulants. Whilst considerable progress has been made towards incorporating research outcomes into operational policy and practice, we outline how this developing evidence-base might be used to inform future iterations of mass casualty decontamination guidance.


Asunto(s)
Liberación de Peligros Químicos , Planificación en Desastres , Incidentes con Víctimas en Masa , Descontaminación , Urgencias Médicas , Sustancias Peligrosas , Humanos
5.
Artículo en Inglés | MEDLINE | ID: mdl-33802332

RESUMEN

Background: Health care systems in the United States are continuously expanding and contracting spaces to treat patients with coronavirus disease 2019 (COVID-19) in intensive care units (ICUs). As a result, hospitals must effectively decontaminate and contain severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in constructed and deconstructed ICUs that care for patients with COVID-19. We assessed decontamination of a COVID-19 ICU and examined the containment efficacy of combined contact and droplet precautions in creating and maintaining a SARS-CoV-2-negative ICU "antechamber". Methods: To examine the efficacy of chemical decontamination, we used high-density, semi-quantitative environmental sampling to detect SARS-CoV-2 on surfaces in a COVID-19 ICU and COVID-19 ICU antechamber. Quantitative real-time polymerase chain reaction was used to measure viral RNA on surfaces. Viral location mapping revealed the distribution of viral RNA in the COVID-19 ICU and COVID-19 ICU antechamber. Results were further assessed using loop-mediated isothermal amplification. Results: We collected 224 surface samples pre-decontamination and 193 samples post-decontamination from a COVID-19 ICU and adjoining COVID-19 ICU antechamber. We found that 46% of antechamber objects were positive for SARS-CoV-2 pre-decontamination despite the construction of a swinging door barrier system, implementation of contact precautions, and installation of high-efficiency particulate air filters. The object positivity rate reduced to 32.1% and viral particle rate reduced by 95.4% following decontamination. Matched items had an average of 432.2 ± 2729 viral copies/cm2 pre-decontamination and 19.2 ± 118 viral copies/cm2 post-decontamination, demonstrating significantly reduced viral surface distribution (p < 0.0001). Conclusions: Environmental sampling is an effective method for evaluating decontamination protocols and validating measures used to contain SARS-CoV-2 viral particles. While chemical decontamination effectively removes detectable viral RNA from surfaces, our approach to droplet/contact containment with an antechamber was not highly effective. These data suggest that hospitals should plan for the potential of aerosolized virions when creating strategies to contain SARS-CoV-2.


Asunto(s)
Descontaminación , Humanos , Unidades de Cuidados Intensivos , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico
6.
Int J Oral Maxillofac Implants ; 36(2): 271-280, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33909716

RESUMEN

PURPOSE: Assessment of in vitro efficacy of three different nonsurgical implant surface decontamination methods in three peri-implant bone defect simulation models. MATERIALS AND METHODS: A total of 180 implants were allocated to differently angulated (30, 60, and 90 degrees) peri-implant bone defect resin models, each covered by a mucosa mask. All implants were stained with indelible red color and assigned to one of the three defect models. In each simulated bone defect group, 20 implants were decontaminated for 2 minutes with a curette (CUR), sonic scaler (SOSC), or air-powder abrasion device (APA) with glycine powder. Photos were taken from both sides of each implant to measure the percentage of uncleaned implant surface area. Scanning electron microscopy (SEM) was used to assess the implant surface for morphologic damage. RESULTS: Among the three defect angulations, a significantly different cleaning efficacy (P < .001) for each treatment method was found (30 degrees: CUR [67.33%], SOSC [62.70%], APA [39.33%]; 60 degrees: CUR [61.59%], SOSC [54.31%], APA [23.91%]; 90 degrees: CUR [66.82%], SOSC [55.77%], APA [28.03%]). SEM did not show any considerable surface damage after APA treatment in comparison with after CUR or SOSC. CONCLUSION: Air-powder abrasion proved to be the most efficient nonsurgical treatment device for each type of defect in this in vitro model with the least noticeable surface change. No decontamination method resulted in complete cleaning of the color remnants on the implant surface.


Asunto(s)
Implantes Dentales , Periimplantitis , Descontaminación , Humanos , Microscopía Electrónica de Rastreo , Periimplantitis/terapia , Polvos , Propiedades de Superficie , Titanio
7.
Water Sci Technol ; 83(5): 985-992, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33724930

RESUMEN

Active chlorine decontaminants like hypochlorite are used to destroy chemical warfare agents (CWAs) such as HD, VX and GD due to the former's strong oxidation capacity and high nucleophilicity. In this paper, experiments were performed to identify the main factors affecting agent recovery from decon water. Based on the results, a method to recover residual CWAs from hypochlorite decon water before quantitative determination by GC was developed. The results showed that the extraction solvent was a critical determinant of high CWA recovery. Dichloromethane was more suitable than petroleum either, especially for samples containing GD or low residual CWAs. For VX-containing samples, the use of an alkali solution improved VX recovery. Neutralization was also important for a high CWA recovery, especially for samples with low CWA concentrations and/or strong decontaminant reactivity. The use of 15% sodium sulfite as the neutralization solution gave the best results for hypochlorite decon water. When the optimized conditions of simultaneous sodium sulfite neutralization and dichloromethane extraction were used, the recovery of HD, VX and GD in hypochlorite decon water was greater than 85% at a concentration range of 20 mg/L to 10,000 mg/L.


Asunto(s)
Sustancias para la Guerra Química , Ácido Hipocloroso , Sustancias para la Guerra Química/análisis , Descontaminación , Compuestos Organotiofosforados , Agua
8.
J Photochem Photobiol B ; 217: 112168, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33714723

RESUMEN

Worldwide shortages of personal protective equipment during COVID-19 pandemic has forced the implementation of methods for decontaminating face piece respirators such as N95 respirators. The use of UV irradiation to reduce bioburden of used respirators attracts attention, making proper testing protocols of uttermost importance. Currently artificial saliva is used but its comparison to human saliva from the UV disinfection perspective is lacking. Here we characterize UV spectra of human and artificial saliva, both fresh and after settling, to test for possible interference for UV-based disinfection. ASTM 2720 artificial saliva recipe (with either porcine or bovine mucin) showed many discrepancies from average (N = 18) human saliva, with different mucins demonstrating very different UV absorbance spectra, resulting in very different UV transmittance at different wavelength. Reducing porcine mucin concentration from 3 to 1.7 g/L brought UVA254 in the artificial saliva to that of average human saliva (although not for other wavelengths), allowing 254 nm disinfection experiments. Phosphate saline and modified artificial saliva were spiked with 8.6 log CFU/ml B. subtilis spores (ATCC 6633) and irradiated at dose of up to 100 mJ/cm2, resulting in 5.9 log inactivation for a saline suspension, and 2.8 and 1.1 log inactivation for ASTM-no mucin and ASTM-1.7 g/L porcine mucin 2 µL dried droplets, respectively. UVC irradiation of spores dried in human saliva resulted in 2.3 and 1.5 log inactivation, depending on the size of the droplets (2 vs 10 µL, respectively) dried on a glass surface. Our results suggest that in the presence of the current standard dried artificial saliva it is unlikely that UVC can achieve 6 log inactivation of B. subtilis spores using a realistic UV dose (e.g. less than 2 J/cm2) and the ATSM saliva recipe should be revised for UV decontamination studies.


Asunto(s)
Desinfección/métodos , Saliva/química , Saliva/efectos de la radiación , Animales , Bacillus subtilis/efectos de la radiación , Canadá , Bovinos , Descontaminación/métodos , Femenino , Humanos , Israel , Masculino , Mucinas/química , Saliva/microbiología , Manejo de Especímenes/métodos , Espectrofotometría Ultravioleta , Esporas Bacterianas/efectos de la radiación , Rayos Ultravioleta
9.
JAMA ; 325(13): 1296-1317, 2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33656543

RESUMEN

Importance: The COVID-19 pandemic has resulted in a persistent shortage of personal protective equipment; therefore, a need exists for hospitals to reprocess filtering facepiece respirators (FFRs), such as N95 respirators. Objective: To perform a systematic review to evaluate the evidence on effectiveness and feasibility of different processes used for decontaminating N95 respirators. Evidence Review: A search of PubMed and EMBASE (through January 31, 2021) was completed for 5 types of respirator-decontaminating processes including UV irradiation, vaporized hydrogen peroxide, moist-heat incubation, microwave-generated steam, and ethylene oxide. Data were abstracted on process method, pathogen removal, mask filtration efficiency, facial fit, user safety, and processing capability. Findings: Forty-two studies were included that examined 65 total types of masks. All were laboratory studies (no clinical trials), and 2 evaluated respirator performance and fit with actual clinical use of N95 respirators. Twenty-seven evaluated UV germicidal irradiation, 19 vaporized hydrogen peroxide, 9 moist-heat incubation, 10 microwave-generated steam, and 7 ethylene oxide. Forty-three types of N95 respirators were treated with UV irradiation. Doses of 1 to 2 J/cm2 effectively sterilized most pathogens on N95 respirators (>103 reduction in influenza virus [4 studies], MS2 bacteriophage [3 studies], Bacillus spores [2 studies], Escherichia virus MS2 [1 study], vesicular stomatitis virus [1 study], and Middle East respiratory syndrome virus/SARS-CoV-1 [1 study]) without degrading respirator components. Doses higher than 1.5 to 2 J/cm2 may be needed based on 2 studies demonstrating greater than 103 reduction in SARS-CoV-2. Vaporized hydrogen peroxide eradicated the pathogen in all 7 efficacy studies (>104 reduction in SARS-CoV-2 [3 studies] and >106 reduction of Bacillus and Geobacillus stearothermophilus spores [4 studies]). Pressurized chamber systems with higher concentrations of hydrogen peroxide caused FFR damage (6 studies), while open-room systems did not degrade respirator components. Moist heat effectively reduced SARS-CoV-2 (2 studies), influenza virus by greater than 104 (2 studies), vesicular stomatitis virus (1 study), and Escherichia coli (1 study) and preserved filtration efficiency and facial fit for 11 N95 respirators using preheated containers/chambers at 60 °C to 85 °C (5 studies); however, diminished filtration performance was seen for the Caron incubator. Microwave-generated steam (1100-W to 1800-W devices; 40 seconds to 3 minutes) effectively reduced pathogens by greater than 103 (influenza virus [2 studies], MS2 bacteriophage [3 studies], and Staphylococcus aureus [1 study]) and maintained filtration performance in 10 N95 respirators; however, damage was noted in least 1 respirator type in 4 studies. In 6 studies, ethylene oxide preserved respirator components in 16 N95 respirator types but left residual carcinogenic by-product (1 study). Conclusions and Relevance: Ultraviolet germicidal irradiation, vaporized hydrogen peroxide, moist heat, and microwave-generated steam processing effectively sterilized N95 respirators and retained filtration performance. Ultraviolet irradiation and vaporized hydrogen peroxide damaged respirators the least. More research is needed on decontamination effectiveness for SARS-CoV-2 because few studies specifically examined this pathogen.


Asunto(s)
Descontaminación/métodos , Equipo Reutilizado , Esterilización/métodos , Óxido de Etileno , Calor , Humanos , Peróxido de Hidrógeno , Vapor , Esterilización/economía , Rayos Ultravioleta
10.
Emerg Infect Dis ; 27(4): 1229-1231, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33755002

RESUMEN

Severe acute respiratory syndrome coronavirus 2 can persist on surfaces, suggesting possible surface-mediated transmission of this pathogen. We found that fomites might be a substantial source of transmission risk, particularly in schools and child daycares. Combining surface cleaning and decontamination with mask wearing can help mitigate this risk.


Asunto(s)
Transmisión de Enfermedad Infecciosa/prevención & control , Fómites/virología , Control de Infecciones , /aislamiento & purificación , Anciano , Número Básico de Reproducción , /prevención & control , /virología , Niño , Jardines Infantiles/normas , Descontaminación/métodos , Contaminación de Equipos/prevención & control , Desinfección de las Manos/métodos , Humanos , Control de Infecciones/instrumentación , Control de Infecciones/métodos , Máscaras , Casas de Salud/normas , Instituciones Académicas/normas , Estados Unidos/epidemiología
11.
Rev Gaucha Enferm ; 42(spe): e20200146, 2021.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-33787720

RESUMEN

OBJECTIVE: To evaluate the protocols on decontamination/reuse of N95 masks available in the literature in times of the Covid-19 pandemic. METHOD: Integrative literature review, in the period from 2010 to 2020, on the databases MEDLINE/PubMed, Science Direct, Cochrane, SAGE journals, Web of Science, Scopus, Embase and Wiley, with the descriptors Masks AND Respiratory protective devices; Mask OR N95 AND Covid-19; N95 AND Respirators; Decontamination AND N95 AND Coronavirus; Facemask OR Pandemic. RESULTS: Twelve studies were included, of which 3 (30.0%) used ultraviolet germicidal irradiation and indicated mask deterioration between 2 and 10 cycles, 4 (40.0%) used hydrogen peroxide vapor, and seal loss varied from 5 to 20 cycles, 4 (33.3%) evaluated the structural integrity of the N95 mask through visual inspection and 6 (54.4%), its filtration efficiency. CONCLUSION: Reuse strategies to overcome a shortage of devices in the face of the pandemic challenge the current concept for good practices in health-product processing.


Asunto(s)
/epidemiología , Descontaminación/métodos , Equipo Reutilizado , Pandemias , Antiinfecciosos Locales , Desinfectantes , Desinfección/métodos , Óxido de Etileno , Filtración/instrumentación , Humanos , Peróxido de Hidrógeno , Rayos Ultravioleta
12.
Am J Kidney Dis ; 77(5): 796-809, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33771393

RESUMEN

Since maintenance hemodialysis (HD) first became available in the United States in 1962, there has been tremendous growth in the population of patients with kidney failure. HD has become a routine treatment carried out in outpatient clinics, hospitals, nursing facilities, and in patients' homes. Although it is a complex procedure, HD is quite safe. Serious complications are uncommon due to the use of modern HD machines and water treatment systems as well as the development of strict protocols to monitor various aspects of the HD treatment. The practicing nephrologist must be knowledgeable about life-threatening complications that can occur during HD and be able to recognize, manage, and prevent them. This installment in the AJKD Core Curriculum in Nephrology reviews the pathogenesis, management, and prevention of 9 HD emergencies. The HD emergencies covered include dialyzer reactions, dialysis disequilibrium syndrome, uremic/dialysis-associated pericarditis, air embolism, venous needle dislodgement, vascular access hemorrhage, hemolysis, dialysis water contamination, and arrhythmia episodes.


Asunto(s)
Urgencias Médicas , Fallo Renal Crónico/terapia , Diálisis Renal/efectos adversos , Arritmias Cardíacas/etiología , Arritmias Cardíacas/fisiopatología , Arritmias Cardíacas/terapia , Edema Encefálico , Descontaminación , Soluciones para Diálisis/normas , Embolia Aérea/etiología , Embolia Aérea/fisiopatología , Embolia Aérea/terapia , Transferencias de Fluidos Corporales , Hemólisis , Hemorragia/etiología , Hemorragia/fisiopatología , Hemorragia/terapia , Humanos , Hipersensibilidad/etiología , Hipersensibilidad/fisiopatología , Hipersensibilidad/terapia , Riñones Artificiales/efectos adversos , Agujas , Nefrología , Pericarditis/etiología , Pericarditis/fisiopatología , Pericarditis/terapia , Falla de Prótesis , Esterilización , Uremia/complicaciones , Purificación del Agua/normas
13.
PLoS One ; 16(3): e0248487, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33735216

RESUMEN

A gas-phase Advanced Oxidation Process (gAOP) was evaluated for decontaminating N95 and surgical masks. The continuous process was based on the generation of hydroxyl-radicals via the UV-C (254 nm) photo-degradation of hydrogen peroxide and ozone. The decontamination efficacy of the gAOP was dependent on the orientation of the N95 mask passing through the gAOP unit with those positioned horizontally enabling greater exposure to hydroxyl-radicals compared to when arranged vertically. The lethality of gAOP was independent of the applied hydrogen peroxide concentration (2-6% v/v) but was significantly (P<0.05) higher when H2O2 was introduced into the unit at 40 ml/min compared to 20 ml/min. A suitable treatment for N95 masks was identified as 3% v/v hydrogen peroxide delivered into the gAOP reactor at 40 ml/min with continuous introduction of ozone gas and a UV-C dose of 113 mJ/cm2 (30 s processing time). The treatment supported >6 log CFU decrease in Geobacillus stearothermophilus endospores, > 8 log reduction of human coronavirus 229E, and no detection of Escherichia coli K12 on the interior and exterior of masks. There was no negative effect on the N95 mask fitting or particulate efficacy after 20 passes through the gAOP system. No visual changes or hydrogen peroxide residues were detected (<1 ppm) in gAOP treated masks. The optimized gAOP treatment could also support >6 log CFU reduction of endospores inoculated on the interior or exterior of surgical masks. G. stearothermophilus Apex spore strips could be applied as a biological indicator to verify the performance of gAOP treatment. Also, a chemical indicator based on the oxidative polymerization of pyrrole was found suitable for reporting the generation of hydroxyl-radicals. In conclusion, gAOP is a verifiable treatment that can be applied to decontaminate N95 and surgical masks without any negative effects on functionality.


Asunto(s)
Descontaminación/métodos , Máscaras/virología , Gases/química , Humanos , Peróxido de Hidrógeno/química , Radical Hidroxilo/química , Oxidación-Reducción , Ozono/química , Fotólisis
14.
Medicine (Baltimore) ; 100(13): e25285, 2021 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-33787613

RESUMEN

ABSTRACT: Surface treatment of medical devices may be a way of avoiding the need for replacement of these devices and the comorbidities associated with infection. The aim of this study was to evaluate whether pre- and postcontamination washing of 2 prostheses with different textures can decrease bacterial contamination.The following microorganisms were evaluated: Staphylococcus aureus, Staphylococcus epidermidis, Proteus mirabilis and Enterococcus faecalis. Silicone and expanded polytetrafluoroethylene vascular prostheses were used and divided into 3 groups: prostheses contaminated; prostheses contaminated and treated before contamination; and prostheses contaminated and treated after contamination. Treatments were performed with antibiotic solution, chlorhexidine and lidocaine. After one week of incubation, the prostheses were sown in culture medium, which was incubated for 48 hours. The area of colony formation was evaluated by fractal dimension, an image analysis tool.The antibiotic solution inhibited the growth of S epidermidis and chlorhexidine decrease in 53% the colonization density for S aureus in for both prostheses in the pre-washing. In postcontamination washing, the antibiotic solution inhibited the growth of all bacteria evaluated; there was a 60% decrease in the colonization density of S aureus and absence of colonization for E faecalis with chlorhexidine; and lidocaine inhibited the growth of S aureus in both prostheses.Antibiotic solution showed the highest efficiency in inhibiting bacterial growth, especially for S epidermidis, in both washings. Lidocaine was able to reduce colonization by S aureus in post-contamination washing, showing that it can be used as an alternative adjuvant treatment in these cases.


Asunto(s)
Prótesis Vascular/microbiología , Descontaminación/métodos , Desinfectantes/administración & dosificación , Infecciones Relacionadas con Prótesis/prevención & control , Antibacterianos/administración & dosificación , Recuento de Colonia Microbiana , Enterococcus faecalis/crecimiento & desarrollo , Humanos , Lidocaína/administración & dosificación , Politetrafluoroetileno , Diseño de Prótesis , Infecciones Relacionadas con Prótesis/microbiología , Proteus mirabilis/crecimiento & desarrollo , Siliconas , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus epidermidis/crecimiento & desarrollo
15.
Bioresour Technol ; 329: 124889, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33662854

RESUMEN

The study aims to investigate the feasibility of anaerobic co-landfilling of effluent treatment plant sludge (ETPS) from paper mill and municipal solid waste (MSW) in prismoidal shaped simulated anaerobic landfill bioreactors. Both ETPS and MSW were co-disposed in 0:100 (R1), 25:75 (R2), 50:50 (R3) and 75:25 (R4) ratios. Periodic assessments of leachate characteristics and biomethane production were carried out for 300 days. ETPS co-disposal with MSW showed considerable reduction in biochemical oxygen demand of leachate (R2: 95.9%, R3: 97.5% and R4: 93.2%). Moreover, cumulative methane gas generations were 2.974, 6.085 and 4.653 times more in R2, R3 and R4 bioreactors as compared to R1. Gompertz growth model was found in well-fitting for methane generation with the observed data. Correlogram plotted among leachate parameters exhibited exclusive relationships and justified leachate trends. This simulation of co-landfilling could be baseline study for the implementation of technology at pilot scale.


Asunto(s)
Eliminación de Residuos , Contaminantes Químicos del Agua , Anaerobiosis , Reactores Biológicos , Descontaminación , Metano , Aguas del Alcantarillado , Residuos Sólidos , Instalaciones de Eliminación de Residuos , Contaminantes Químicos del Agua/análisis
16.
Waste Manag ; 124: 102-109, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33611154

RESUMEN

The 2011-2016 reports from the Food and Agriculture Organization of the United Nations has stated that annual food loss and waste occurs on a massive scale in fisheries and aquaculture. This study aimed to explore advanced technologies to recycle wasted salmon as an industrial resource with high commercial value by applying enzymatic hydrolysis under HPCD. Our results showed that HPCD treatment at 50 °C and 1 MPa for 16 h effectively prevents salmon from microbial contamination. Real-time PCR analysis demonstrated that HPCD was also able to inhibit an increase in bacteria at moderate temperatures. Based on NGS analysis, there was a very low abundance of Bacillus and some histamine producers, such as Pseudomonas, Acinetobacter, Enterobacter, and Klebsiella, detected in samples treated using HPCD at 50 °C and 1 MPa for 16 h. Hydrolysate analysis showed that HPCD treatment at 1 MPa did not affect the hydrolysates from salmon. It is anticipated that the results from this study will support the application of HPCD in industrial enzymatic hydrolysis and increase the sustainability of bio-based materials.


Asunto(s)
Dióxido de Carbono , Microbiología de Alimentos , Animales , Descontaminación , Carne , Salmón
17.
Int J Food Microbiol ; 343: 109088, 2021 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-33621831

RESUMEN

Bacterial spores are a major challenge in industrial decontamination processes owing to their extreme resistance. High-pressure (HP) of 150 MPa at 37 °C can trigger the germination of spores, making them lose their extreme resistance. Once their resistance is lost, germinated spores can easily be inactivated by a mild decontamination step. The implementation of this gentle germination-inactivation strategy is hindered by the presence of a subpopulation of so-called high-pressure superdormant (HPSD) spores, which resist germination or germinate only very slowly in response to HP. It is essential to understand the properties of HPSD spores and the underlying causes of superdormancy to tackle superdormant spores and further develop germination-inactivation strategies involving HP. This study investigated factors influencing the prevalence of HPSD spores and successfully isolated them by combining buoyant density centrifugation and fluorescence-activated cell sorting, which allowed further characterisation of HPSD spores for the first time. The prevalence of HPSD spores was shown to be strongly dependent on the HP dwell time, with increasing treatment times reducing their prevalence. Spore mutants lacking major germinant receptors further showed a highly increased prevalence of HPSD spores; 93% of the spores remained dormant even after a prolonged HP dwell time of 40 min. In contrast to nutrient germination, sublethal heat treatment of 75 °C for 30 min prior to pressure treatment did not induce spore activation and increase germination. The isolated HPSD spores did not show visible structural differences compared to the initial dormant spores when investigated with transmission electron microscopy. Re-sporulated HPSD spores showed similar germination capacity compared to the initial dormant spores, indicating that HPSD spores are most likely not genetically different from the rest of the population. Moreover, the majority of HPSD spores germinated when exposed a second time to the same germination treatment; however, the germination capacity was lower than that of the initial population. The fact that the majority of spores lost superdormancy when exposed a second time to the same trigger makes it unlikely that there is one factor that determines whether a spore germinates with a certain HP treatment or not. Instead, it seems possible that there are other reversible or cumulative causes. This study investigated the factors influencing spore HP superdormancy to improve the understanding of HPSD spores with regard to their stability, germination capacity, and potential underlying causes of spore HP superdormancy. This knowledge will contribute to the development of HP-based germination-inactivation strategies for gentle but effective spore control.


Asunto(s)
Bacillus subtilis/fisiología , Esporas Bacterianas/crecimiento & desarrollo , Esporas Bacterianas/aislamiento & purificación , Esporas Bacterianas/fisiología , Bacillus subtilis/genética , Bacillus subtilis/crecimiento & desarrollo , Bacillus subtilis/aislamiento & purificación , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Descontaminación , Citometría de Flujo , Mutación , Presión , Esporas Bacterianas/genética , Temperatura , Factores de Tiempo
19.
Environ Pollut ; 274: 116536, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33529903

RESUMEN

The high global consumption of ibuprofen and its limited elimination by wastewater treatment plants (WWTPs), has led to the contamination of aquatic systems by this common analgesic and its metabolites. The potentially negative environmental and public health effects of this emerging contaminant have raised concerns, driving the demand for treatment technologies. The implementation of bacteria which mineralize organic contaminants in biopurification systems used to decontaminate water or directly in processes in WWTPs, is a cheap and sustainable means for complete elimination before release into the environment. In this work, an ibuprofen-mineralizing bacterial strain isolated from sediments of the River Elbe was characterized and assayed to remediate different ibuprofen-polluted media. Strain RW412, which was identified as Sphingopyxis granuli, has a 4.48 Mb genome which includes plasmid sequences which harbor the ipf genes that encode the first steps of ibuprofen mineralization. Here, we confirm that these genes encode enzymes which initiate CoA ligation to ibuprofen, followed by aromatic ring activation by a dioxygenase and retroaldol cleavage to unequivocally produce 4-isobutylcatechol and propionyl-CoA which then undergo further degradation. In liquid mineral salts medium, the strain eliminated more than 2 mM ibuprofen within 74 h with a generation time of 16 h. Upon inoculation into biopurification systems, it eliminated repeated doses of ibuprofen within a few days. Furthermore, in these systems the presence of RW412 avoided the accumulation of ibuprofen metabolites. In ibuprofen-spiked effluent from a municipal WWTP, ibuprofen removal by this strain was 7 times faster than by the indigenous microbiota. These results suggest that this strain can persist and remain active under environmentally relevant conditions, and may be a useful innovation to eliminate this emerging contaminant from urban wastewater treatment systems.


Asunto(s)
Sphingomonadaceae , Contaminantes Químicos del Agua , Purificación del Agua , Descontaminación , Ibuprofeno , Eliminación de Residuos Líquidos , Aguas Residuales , Contaminantes Químicos del Agua/análisis
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