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Birds, including canaries and other birds, have become increasingly popular as pets. Bird fairs, where breeders gather and show their production in a championship setting, present a setting for possible Salmonella spp. contamination and transmission. Therefore, this study estimated the rate of Salmonella spp. isolation from cage papers, located in the bottom of cages of exotic pet birds, including canaries. Collected Salmonella isolates were used to determine the antimicrobial resistance profile to 52 antibiotics and 17 commercial disinfectants, based on pure or a mixture of acids, alcohols, aldehydes, alkalis, halogens, peroxygen, and quaternary ammonium compounds. The samples consisted of 774 cage papers taken in the 2015 Argentinean canary breeder championship, pooling three cage papers into one sterile sampling bag. Only one pool of the cage papers was positive for Salmonella spp. (0.4%), which belonged to the sample from three frill canary cages. Two strains of Salmonella serotype Glostrup were isolated, which were only resistant to sulfonamides and erythromycin and sensitive to alkali-based product PL301 AS. Although the rate of Salmonella spp. isolation from cage papers in an Argentinean canary breeder championship is low, it should not be discounted because Salmonella ser. Glostrup can be a source of human Salmonella outbreaks and they show high resistance to disinfecting products.

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The evaluation of the ecotoxicological effects of the effluent after treatment with peracetic acid is relevant to help establish reference concentrations for the disinfection process and waste recovery. Therefore, the objective of this work was to evaluate the ecotoxicity of effluent from a bovine slaughterhouse treated with peracetic acid on Girardia tigrina. The toxicity bioassays for planaria were the acute test (LC50) and chronic assays: locomotion, regeneration, reproduction and fertility. The results showed that the effluent treated with peracetic acid showed less toxicity than the effluent without application of peracetic acid. The effluent after peracetic acid application showed a chronic toxic effect in the reduction of locomotor speed in all studied disinfectant concentrations (0.8, 1.6, 3.3 and 6.6 µg L-1 of peracetic acid) and a delay in the formation of G. tigrina photoreceptors at the concentration of 6.6 µg L-1 of peracetic acid. Peracetic acid concentrations of 0.8, 1.6 and 3.3 µg L-1 were not toxic for blastema regeneration, photoreceptor and auricle formation, fecundity and fertility. In addition, this study assists in defining doses of peracetic acid to be recommended in order to ensure the wastewater disinfection process without causing harm to aquatic organisms.

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AIM: The objective of this study was to develop nanostructured gels as biocompatible intracanal disinfectants by one-step microwave radiation-assisted synthesis. METHODS: Polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) were used as a support network, and polyethylene glycol (PEG) was used as a reducing agent. The gels were characterized by measuring the swelling ratio (SR) and rheological properties and by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM). The antibacterial effects of each gel were evaluated against the endodontic clinical strain Enterococcus faecalis. Then, the viability of the 21-day mature multispecies bacterial biofilm was assessed using confocal microscopy in an ex vivo model, where the biofilm was exposed to the mix of nanogels. The cell proliferation, viability, and morphology of human periodontal ligament (HPDL) cells were quantified using a real-time IncuCyte® S3 Live-Cell System. Viability was measured by confocal microscopy using an ex vivo model exposing a 21-day mature multispecies bacterial biofilm to the mix of nanogels. RESULTS: The antibacterial activity of the gels coincided with the superficial characterization and the solubility of the gel in the growth medium. Gels with higher viscosity (327.85-980.58 Pa s), higher dissolution (42-70%SR), and lower porosity (no porosity and 611.63 nm) showed excellent antibacterial activity against E. faecalis. Despite their physicochemical characteristics, CuNPs gels showed greater effectiveness against E. faecalis.These nanostructured gels with high PVA concentrations promote HPDL cells proliferation while still exerting antibacterial properties. Mix of nanogels showed an increase non-viable cells biomass from at of application. CONCLUSIONS: The use of biocompatible polymers influences the physicochemical, bactericidal, and cytotoxic response, making these materials potential disinfectant agents against resistant bacteria with good biocompatibility and improved HPDL cells proliferation.

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The large-scale use of alcohol (OH)-based disinfectants to control pathogenic viruses is of great concern because of their side effects on humans and harmful impact on the environment. There is an urgent need to develop safe and environmentally friendly disinfectants. Essential oils (EOs) are generally recognized as safe (GRAS) by the FDA, and many exhibit strong antiviral efficacy against pathogenic human enveloped viruses. The present study investigated the virucidal disinfectant activity of solutions containing EO and OH against DENV-2 and CHIKV, which were used as surrogate viruses for human pathogenic enveloped viruses. The quantitative suspension test was used. A solution containing 12% EO + 10% OH reduced > 4.0 log10 TCID50 (100% reduction) of both viruses within 1 min of exposure. In addition, solutions containing 12% EO and 3% EO without OH reduced > 4.0 log10 TCID50 of both viruses after 10 min and 30 min of exposure, respectively. The binding affinities of 42 EO compounds and viral envelope proteins were investigated through docking analyses. Sesquiterpene showed the highest binding affinities (from -6.7 to -8.0 kcal/mol) with DENV-2 E and CHIKV E1-E2-E3 proteins. The data provide a first step toward defining the potential of EOs as disinfectants.

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This study aimed to evaluate in vitro the possible mechanisms underlying the estrogenic potential of benzalkonium chloride (BAC) as a disinfectant emerging contaminant. Effects of BAC at the environmentally-relevant concentrations on estrogen synthesis and estrogen receptor (ER) signaling were assessed using the H295R steroidogenesis assay and the MCF-7 proliferation assay, respectively. Results showed that exposure to BAC at concentrations of 1.0-1.5 mg/L for 48 h significantly increased estradiol production of H295R cells in a concentration-dependent manner. Transcription of steroidogenic genes 3β‐HSD2, 17β‐HSD1, 17β‐HSD4, and CYP19A were significantly enhanced by BAC. In ER-positive MCF-7 cells, exposure to 0.5-1.5 mg/L BAC for 48 h significantly promoted cell proliferation and increased the expressions of ERα and G-protein coupled estrogen receptor 1. Flow cytometry analysis showed that 0.5-1.5 mg/L BAC significantly decreased the percentage of cells in G0/G1 phase, increased the percentage in S phase, and BAC at concentrations of 1.0 and 1.5 mg/L increased the G2/M phase cells. Findings of the study suggested that BAC at environmentally-relevant concentrations might act as a xenoestrogen through its inhibitory effect on steroidogenesis and ER-mediated mechanism.

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Abstract The purpose of this study was to compare the effect of different disinfection protocols of dentin on bond strength of an MDP-containing universal adhesive. Twelve extracted mandibular third molars were separated horizontally at the mid-coronal of crown to get smooth and sound dentin surfaces using low-speed diamond saw. The teeth were randomly fallen into four groups: chlorhexidine (CHX), ozone, Er,Cr:YSGG laser irradiation (LASER) and no treatment (control). After cavity disinfection application, a universal adhesive (G-Premio Bond) was applied to the surface of dentin according to self-etch mode as instructed by the manufacturer. After incremental built-up of composite resin (Charisma Smart), the specimens were immersed in distilled water at 37°C for 24h. Dentin/composite beams with 1 mm² cross sectional area were produced and micro-tensile bond strength (µTBS) was applied on these beams (n=20). Failure mods were determined under a stereomicroscope at ×40. The resin penetration of samples stained with Rhodamine B fluorochrome dye was examined with a confocal laser scanning microscope. Statistical analysis was performed with SPSS-22. Test results were analyzed using One-way Anova and Tukey HSD Post-Hoc tests (p0.5). All applications of cavity disinfection procedures decreased the µTBS of the resin-dentin interface.

Resumen El propósito de este estudio fue comparar el efecto de diferentes protocolos de desinfección de la dentina sobre la fuerza de unión de un adhesivo universal que contiene MDP. Doce terceros molares mandibulares extraídos se quebraron horizontalmente en la mitad de la corona para obtener superficies de dentina lisas y sólidas utilizando una sierra de diamante de baja velocidad. Los dientes se dividieron aleatoriamente en cuatro grupos: clorhexidina (CHX), ozono, irradiación con láser Er,Cr:YSGG (LASER) y ningún tratamiento (control). Después de la aplicación de la desinfección de la cavidad, se aplicó un adhesivo universal (G-Premio Bond) a la superficie de la dentina según el modo de autograbado indicado por el fabricante. Después de la obturación con resina compuesta (Charisma Smart), las muestras se sumergieron en agua destilada a 37°C durante 24h. Se produjeron porciones de dentina/resina con un área de sección transversal de 1 mm² y se aplicó una fuerza de adhesión microtensile (µTBS) (n=20). Los modos de falla se determinaron bajo un microscopio estereoscópico a ×40. La penetración de la resina de las muestras teñidas con colorante fluorocromo rodamina B se examinó con un microscopio de barrido láser confocal. El análisis estadístico se realizó con SPSS-22. Los resultados de las pruebas se analizaron utilizando las pruebas post-hoc Anova unidireccional y Tukey HSD (p0.5). Todas las aplicaciones de procedimientos de desinfección de cavidades redujeron el µTBS de la interfaz resina-dentina.

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Previous studies have shown that the combination disinfectant, Ortho-phthalaldehyde and benzyldimethyldodecylammonium chloride (ODB), can effectively kill a variety of microorganisms, such as Escherichia coli, Staphylococcus aureus, and Candida albicans. To observe the sporicidal ability and mechanism of ODB for spores, Bacillus subtilis spores were used as the research object in this experiment. TEM images revealed that ODB destroyed the integrity of the coat, cortex, and inner membrane of the spores after 0.5-h treatment, and the nuclear material was also broken and exuded after 4-h treatment. The broken structure led to the release of dipicolinic acid (DPA) in large amount. The results show that B. subtilis spores can be effetely killed by ODB through destroying the structure of the spores.

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Aspergillus and Fusarium cause a broad spectrum of infections in humans, mainly in immunocompromised patients. Among these, patients undergoing hemodialysis are highly susceptible to infections, requiring a constant and adequate environmental disinfection program. Nevertheless, monitoring the residual disinfectants can contribute to the morbidity and mortality reduction in these patients. Here, we evaluated the susceptibility of Aspergillus spp. (n=19) and Fusarium spp. (n=13) environmental isolates against disinfectants (acetic acid, citric acid, peracetic acid, sodium hypochlorite, and sodium metabisulphite) at different concentrations and time exposures. Also, we investigated the in vivo toxicity of the peracetic acid residual concentration in mice. Fusarium isolates were identified by F. equiseti, F. oxysporum and F. solani while Aspergillus presented clinically relevant species (A. fumigatus, A. niger and A. terreus) and environmental ones. Against planktonic cells, only two disinfectants (acetic acid and sodium hypochlorite) showed a fungicidal effect on Fusarium spp., while only one (sodium hypochlorite) was effective against Aspergillus spp. Both fungi formed robust in vitro biofilms with large amounts of the extracellular matrix, as evidenced by electron micrographs. Exposure of fungal biofilms to disinfectants showed sensitivity to three (acetic, citric, and peracetic acids), although the concentrations and times of exposure varied according to the fungal genus. Mice exposure to the residual dose of peracetic acid during 60 weeks showed anatomopathological, hematological, and biochemical changes. The implementation of news control measures and those that already exist can help reduce infections, the second cause of death and morbidity in these patients, besides providing safety and well-being to them, a priority of any quality health program.

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The elimination of microbial surface contaminants is one of the most important steps in Good Manufacturing Practices in order to maintain food safety. This is usually achieved by detergents and chemical sanitizers, although an increased demand exists for the use of natural products for disinfection purposes. Several natural substances present antibacterial activity against the main foodborne pathogens, demonstrating great potential for use in the food industry. Some difficulties such as high volatility, residual taste and/or degradation by exposure to harsh processing conditions have been reported. Nanoparticle encapsulation appears as a strategy to protect bioactive compounds, maintaining their antimicrobial activity and providing controlled release as well. This article presents the potential of natural antimicrobials and their combination with nanotechnological strategies as an alternative for food surface disinfection and prevent microbial biofilm formation.

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Salmonella is a major cause of foodborne illness worldwide, and poultry and its derived products are the most common food products associated with salmonellosis outbreaks. Some countries, including Brazil, have experienced an increased prevalence of Salmonella Heidelberg among their poultry flocks. Some isolates have also presented high resistance to antimicrobial agents and persist in the poultry farm environment. This study aimed to compare the susceptibility of S. Heidelberg strains isolated in 2006 with those isolated in 2016 against disinfectants and antimicrobial agents. The results showed that all the strains were highly susceptible to sodium hypochlorite, regardless of the conditions and year of isolation. Resistance to benzalkonium chloride varied according to the conditions applied, but not to the year of isolation. Increased antimicrobial resistance from 2006-2016 was observed only for tetracycline. The results suggest that the antimicrobial and disinfectant resistance of S. Heidelberg did not increase for ten years (2006-2016). However, further analysis should include a larger number of S. Heidelberg isolates from poultry origin and additional antimicrobial agents for more precise conclusions about the increasing in antimicrobial resistance in the last years.(AU)

Salmonella é uma das principais causas das doenças transmitidas por alimento em todo o mundo, e a carne de frango e produtos derivados são os principais alimentos associados com surtos de salmonelose em humanos. Alguns países, incluindo o Brasil, têm observado um aumento da ocorrência de Salmonella Heidelberg nas suas granjas avícolas. Além disto, alguns isolados têm apresentado alta resistência aos antimicrobianos e têm persistido no ambiente de produção avícola. Neste contexto, o objetivo deste estudo foi comparar a susceptibilidade de cepas de S. Heidelberg isoladas em 2006 com aquelas isoladas em 2016 contra desinfetantes e agentes antimicrobianos. Os resultados demonstraram que as cepas foram altamente resistentes a hipoclorito de sódio, independentemente das condições e do ano de isolamento. A resistência ao cloreto de benzalcônio variou de acordo com as condições testadas, mas não com o ano de isolamento. Um aumento da resistência aos antimicrobianos de 2006 a 2016 foi observado apenas para tetraciclina. Os resultados sugerem que a resistência aos desinfetantes e aos antimicrobianos não aumentou em um período de dez anos (2006-2016). Entretanto, novas análises devem incluir um número maior de cepas de S. Heidelberg isoladas de fontes avícolas e outros agentes antimicrobianos para uma conclusão mais precisa sobre o aumento da resistência antimicrobiana nos últimos anos.(AU)

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The efficiency of the disinfectants used in the milking management is fundamental to the success in the dairy activity, being a critical point to the control of mastitis. The objective was to evaluate the in vitro efficacy of iodine used in pre and post-dipping against coagulase negative Staphylococcus (CNS). Thus, 53 CNS isolates were studied for the action of the 1.0% disinfectant and their serial dilutions of 0.5%, 0.375% and 0.25%, in addition to two commercial presentations of iodine in concentrations of 0.5% and 0.25%. The rate of CNS inhibition achieved by iodine at 0.375%, 0.5% and 1.0% for 60 seconds, was 60.4%. In 30 seconds, iodine at 0.5% and 1.0% showed a microbial inhibition rate of 52.8% and 56.6%, respectively. The other protocols tested were less efficient. It is concluded that the greatest in vitro disinfectant activity for CNS was demonstrated by iodine at 0.375%, 0.5% and 1.0%, for 60 seconds. Microbial susceptibility tests should be carried out periodically, as well as health education practices and corrective training on the property, in order to ensure udder health and mastitis control.(AU)

A eficiência dos desinfetantes empregados no manejo de ordenha é fundamental no sucesso na atividade leiteira, sendo um ponto crítico ao controle da mastite. Objetivou-se avaliar a eficácia in vitro do iodo utilizado no pré e pós-dipping frente à Staphylococcus coagulase negativa (SCN). Foram estudados 53 isolados de SCN quanto à ação do desinfetante a 1,0% e suas diluições seriadas de 0,5%, 0,375% e 0,25%, além de duas apresentações comerciais nas concentrações de 0,5% e 0,25%. A taxa de inibição de SCN alcançada pelo iodo a 0,375%, 0,5% e 1,0% durante 60 segundos, foi de 60,4%. Em 30 segundos, o iodo a 0,5% e 1,0% apresentaram taxa de inibição microbiana de 52,8% e 56,6%, respectivamente. Os demais protocolos testados foram menos eficientes. Conclui-se que a maior atividade desinfetante in vitro para SCN foi demonstrada pelo iodo a 0,375%, 0,5% e 1,0%, durante 60 segundos. Testes de susceptibilidade microbiana devem ser realizados periodicamente, assim como práticas de educação em saúde e treinamentos corretivos na propriedade, visando garantir a saúde do úbere e o controle da mastite.(AU)

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Salmonella is a major cause of foodborne illness worldwide, and poultry and its derived products are the most common food products associated with salmonellosis outbreaks. Some countries, including Brazil, have experienced an increased prevalence of Salmonella Heidelberg among their poultry flocks. Some isolates have also presented high resistance to antimicrobial agents and persist in the poultry farm environment. This study aimed to compare the susceptibility of S. Heidelberg strains isolated in 2006 with those isolated in 2016 against disinfectants and antimicrobial agents. The results showed that all the strains were highly susceptible to sodium hypochlorite, regardless of the conditions and year of isolation. Resistance to benzalkonium chloride varied according to the conditions applied, but not to the year of isolation. Increased antimicrobial resistance from 2006-2016 was observed only for tetracycline. The results suggest that the antimicrobial and disinfectant resistance of S. Heidelberg did not increase for ten years (2006-2016). However, further analysis should include a larger number of S. Heidelberg isolates from poultry origin and additional antimicrobial agents for more precise conclusions about the increasing in antimicrobial resistance in the last years.(AU)

Salmonella é uma das principais causas das doenças transmitidas por alimento em todo o mundo, e a carne de frango e produtos derivados são os principais alimentos associados com surtos de salmonelose em humanos. Alguns países, incluindo o Brasil, têm observado um aumento da ocorrência de Salmonella Heidelberg nas suas granjas avícolas. Além disto, alguns isolados têm apresentado alta resistência aos antimicrobianos e têm persistido no ambiente de produção avícola. Neste contexto, o objetivo deste estudo foi comparar a susceptibilidade de cepas de S. Heidelberg isoladas em 2006 com aquelas isoladas em 2016 contra desinfetantes e agentes antimicrobianos. Os resultados demonstraram que as cepas foram altamente resistentes a hipoclorito de sódio, independentemente das condições e do ano de isolamento. A resistência ao cloreto de benzalcônio variou de acordo com as condições testadas, mas não com o ano de isolamento. Um aumento da resistência aos antimicrobianos de 2006 a 2016 foi observado apenas para tetraciclina. Os resultados sugerem que a resistência aos desinfetantes e aos antimicrobianos não aumentou em um período de dez anos (2006-2016). Entretanto, novas análises devem incluir um número maior de cepas de S. Heidelberg isoladas de fontes avícolas e outros agentes antimicrobianos para uma conclusão mais precisa sobre o aumento da resistência antimicrobiana nos últimos anos.(AU)

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ABSTRACT: Salmonella is a major cause of foodborne illness worldwide, and poultry and its derived products are the most common food products associated with salmonellosis outbreaks. Some countries, including Brazil, have experienced an increased prevalence of Salmonella Heidelberg among their poultry flocks. Some isolates have also presented high resistance to antimicrobial agents and persist in the poultry farm environment. This study aimed to compare the susceptibility of S. Heidelberg strains isolated in 2006 with those isolated in 2016 against disinfectants and antimicrobial agents. The results showed that all the strains were highly susceptible to sodium hypochlorite, regardless of the conditions and year of isolation. Resistance to benzalkonium chloride varied according to the conditions applied, but not to the year of isolation. Increased antimicrobial resistance from 2006-2016 was observed only for tetracycline. The results suggest that the antimicrobial and disinfectant resistance of S. Heidelberg did not increase for ten years (2006-2016). However, further analysis should include a larger number of S. Heidelberg isolates from poultry origin and additional antimicrobial agents for more precise conclusions about the increasing in antimicrobial resistance in the last years.

RESUMO: Salmonella é uma das principais causas das doenças transmitidas por alimento em todo o mundo, e a carne de frango e produtos derivados são os principais alimentos associados com surtos de salmonelose em humanos. Alguns países, incluindo o Brasil, têm observado um aumento da ocorrência de Salmonella Heidelberg nas suas granjas avícolas. Além disto, alguns isolados têm apresentado alta resistência aos antimicrobianos e têm persistido no ambiente de produção avícola. Neste contexto, o objetivo deste estudo foi comparar a susceptibilidade de cepas de S. Heidelberg isoladas em 2006 com aquelas isoladas em 2016 contra desinfetantes e agentes antimicrobianos. Os resultados demonstraram que as cepas foram altamente resistentes a hipoclorito de sódio, independentemente das condições e do ano de isolamento. A resistência ao cloreto de benzalcônio variou de acordo com as condições testadas, mas não com o ano de isolamento. Um aumento da resistência aos antimicrobianos de 2006 a 2016 foi observado apenas para tetraciclina. Os resultados sugerem que a resistência aos desinfetantes e aos antimicrobianos não aumentou em um período de dez anos (2006-2016). Entretanto, novas análises devem incluir um número maior de cepas de S. Heidelberg isoladas de fontes avícolas e outros agentes antimicrobianos para uma conclusão mais precisa sobre o aumento da resistência antimicrobiana nos últimos anos.

RESUMO

ABSTRACT: The efficiency of the disinfectants used in the milking management is fundamental to the success in the dairy activity, being a critical point to the control of mastitis. The objective was to evaluate the in vitro efficacy of iodine used in pre and post-dipping against coagulase negative Staphylococcus (CNS). Thus, 53 CNS isolates were studied for the action of the 1.0% disinfectant and their serial dilutions of 0.5%, 0.375% and 0.25%, in addition to two commercial presentations of iodine in concentrations of 0.5% and 0.25%. The rate of CNS inhibition achieved by iodine at 0.375%, 0.5% and 1.0% for 60 seconds, was 60.4%. In 30 seconds, iodine at 0.5% and 1.0% showed a microbial inhibition rate of 52.8% and 56.6%, respectively. The other protocols tested were less efficient. It is concluded that the greatest in vitro disinfectant activity for CNS was demonstrated by iodine at 0.375%, 0.5% and 1.0%, for 60 seconds. Microbial susceptibility tests should be carried out periodically, as well as health education practices and corrective training on the property, in order to ensure udder health and mastitis control.

RESUMO: A eficiência dos desinfetantes empregados no manejo de ordenha é fundamental no sucesso na atividade leiteira, sendo um ponto crítico ao controle da mastite. Objetivou-se avaliar a eficácia in vitro do iodo utilizado no pré e pós-dipping frente à Staphylococcus coagulase negativa (SCN). Foram estudados 53 isolados de SCN quanto à ação do desinfetante a 1,0% e suas diluições seriadas de 0,5%, 0,375% e 0,25%, além de duas apresentações comerciais nas concentrações de 0,5% e 0,25%. A taxa de inibição de SCN alcançada pelo iodo a 0,375%, 0,5% e 1,0% durante 60 segundos, foi de 60,4%. Em 30 segundos, o iodo a 0,5% e 1,0% apresentaram taxa de inibição microbiana de 52,8% e 56,6%, respectivamente. Os demais protocolos testados foram menos eficientes. Conclui-se que a maior atividade desinfetante in vitro para SCN foi demonstrada pelo iodo a 0,375%, 0,5% e 1,0%, durante 60 segundos. Testes de susceptibilidade microbiana devem ser realizados periodicamente, assim como práticas de educação em saúde e treinamentos corretivos na propriedade, visando garantir a saúde do úbere e o controle da mastite.

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BACKGROUND AND AIM: The use of antimicrobials in the control of mastitis is of concern in public health due to their inefficiency in targeting microorganisms. Studies with medicinal plants have risen as an alternative to the use of conventional products. The objective of this study was to evaluate the efficacy of an experimental disinfectant based on the essential oil (EO) from Lippia origanoides in preventing the development of new intramammary infections (IMI) in Holstein cows. MATERIALS AND METHODS: The conventional protocol of pre- and post-milking was used and the control (Conventional treatment [CNV]) and experimental (Experimental treatment [PEX]) products containing EO at 120 µL/mL were applied by immersion. Individual milk samples were analyzed using sheep blood agar methodologies and biochemical tests. The efficiency of the treatment was defined by the presence or absence of Staphylococcus aureus, coagulase-negative Staphylococcus, and Streptococcus spp. RESULTS: There were no clinical and subclinical mastitis cases, no lesions in the mucosal of teats, nor dirt score between groups in this study. Both treatments did not influence the occurrence of IMI. CONCLUSION: The results revealed that PEX acts efficiently against microorganisms compared to the disinfection by the conventional product demonstrating the efficacy of the alternative product on the prevention of new IMIs in dairy cows.

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La pandemia producida por el coronavirus SARS-CoV-2 está causando estragos sanitarios y económicos en todo el mundo, obligando a la reorientación de recursos para disminuir el contagio y superar los problemas económicos. En ese sentido se comenzaron a construir y emplear las cabinas de desinfección para eliminar el SARS-CoV-2 de forma externa, las cuales eran colocadas en las entradas de los hospitales para rociar con agentes desinfectantes a las personas que entraban y salían del lugar, a pesar de que los productos empleados están habilitados para ser utilizados sobre objetos y por un tiempo determinado, lo cual representaba un riesgo para la salud del usuario por lo que se requería de un estudio para establecer los peligros relacionados y desaconsejar su utilización.

The pandemic produced by the SARS-CoV-2 coronavirus is causing health and economic havoc throughout the world, forcing the redirection of resources to reduce contagion and overcome economic problems. In this sense, they began to build and use disinfection cabins to eliminate SARS-CoV-2 externally, which were placed at the entrances of hospitals to spray disinfectants with disinfectants to people who entered and left the place, despite the fact that the products used are enabled to be used on objects and for a certain time, which represented a risk to the health of the user, so a study was required to establish the related dangers and advise against their use.

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Tambaqui Colossoma macropomum is the most produced native fish in South America. Besides the lack of knowledge regarding bacteria-stricken diseases, the unappropriated using of off-label therapies are common. In this study, Aeromonas hydrophila pathogenicity for tambaqui was first established by Koch's Postulate. Lethal doses (LD) were settled for investigation of clinical signs and mortality. The antimicrobial activities were investigated by disk-diffusion test against 11 antibiotics and by broth microdilution methods against 3 antibiotics, 7 disinfectants and 11 herbal medicines. LD experiment showed up to 80% of fish mortality, skin darkness, ulcers, hemorrhage, lethargy and hypo/anorexia in all groups, with exception of control. The LD10,50,90 and 99 were established in 4.1 × 107, 8.8 × 107, 1.9 × 108 e 3.6 × 108 CFU/mL, respectively. Ceftriaxone, florfenicol, oxytetracycline and thiamphenicol were considered promising against A. hydrophila. All herbal medicines were classified as bactericides, but clove Eugenia caryophyllata and cinnamon Cinnamomum zeylanicum displayed strongest activities. Among disinfectants, malachite green was the only that did not present acceptable values, discouraging its use. In conclusion, Koch's postulate was fulfilled and tambaqui entered to the vast list of A. hydrophila hosts and promising results of chemical substances were provided, contributing to motile Aeromonas septicemia (MAS) control.

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OBJECTIVES: Coronavirus COVID-19 is spreading very fast in Brazil, requiring innovative strategies for the fast deployment of disinfectants. Panic in population triggered by COVID-19 has caused a shortage of alcohol-based hand sanitizers and disinfectants in many cities of Brazil. Despite the governmental reaction against the outbreak, a risk of shortage of disinfectants still exists. The objective of this research is to investigate an alternative method for the fast deployment of alcohol-based disinfectants to protect the population against COVID-19. METHODS AND RESULTS: This research highlights the feasibility of disinfectant production from common ethanol available in Brazilian gas stations, as a last resort. A four-by-one (4:1) ratio of common alcohol diluted in water meets the minimum requirements set by health agencies for the alcoholic concentration of disinfectants. Risks factors on alcohol dilution process are associated with corresponding measures of risk mitigation for public health and safety. CONCLUSIONS AND PERSPECTIVES: This research proposes a process for the production and deployment of ethanol-based disinfectant from gas stations. However, the implementation is not timely possible for the COVID-19 pandemic due to complexities in the productive process. For the post-COVID-19 period, the authors give three perspectives: (a) future investigation of human dermal toxicity of common ethanol, (b) establishment of a program for the ethanol decontamination, and (c) countries such as the US, Sweden, Thailand, and Colombia to rethink their energy policy for the adoption of biofuel E100 (ethanol and water) instead of E85 (blend of ethanol, gasoline, and water), as part of their biodefense strategy.

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Listeria monocytogenes, a well-known foodborne pathogen and the causative agent of listeriosis, has the ability to persist in food processing environments due to its high adhesion ability in different surfaces, playing an important role in the food industry. The aim of this study was to assess how the main stressing conditions, usually observed in meat processing facilities (sanitizers, NaCl, curing salts), interfere in L. monocytogenes adhesion and biofilm formation. The isolates, representatives of different L. monocytogenes lineages (n = 6) were subjected to four different sanitizers (S1: quaternary ammonium; S2: peracetic acid, hydrogen peroxide and glacial acetic acid, S3: biguanide polyhexamethylene hydrochloride, S4: hydrogen peroxide) to verify adhesion ability and susceptibility based on minimum inhibitory concentration (MIC). In addition, the isolates adhesion and biofilm were assessed up to 72 h under different conditions: sanitizers (MIC values), curing salts and NaCl (both at 5, 7·5, 10%), at different temperatures (4, 12 and 37°C). Despite the effectiveness of sanitizers, isolates presented higher biofilm development when compared to controls in the presence of quaternary ammonium (S1, 1: 1,024) at 4°C, over the tested time (P < 0·05). Furthermore, different responses were observed for the different L. monocytogenes strains tested, providing a better understanding of the persistence of this pathogen in the food processing facilities.

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RESUMO

Freshwater ecosystems are vulnerable to residual concentrations of chemical agents from anthropogenic activities, and the real impacts of such compounds can only be evaluated accurately using ecotoxicological tests. The assessment of ecotoxicological effects of peracetic acid (PAA) and the active chlorine of calcium hypochlorite (Ca(ClO)2) on the insect Chironomus xanthus Meigen (Diptera: Chironomidae) is highly relevant as there are few reports on its effects in fresh water ecosystems. To our best knowledge, this is the first study to assess the chronic toxicity of the compounds to C. xanthus. The toxicity bioassays for C. xanthus included the acute effect (CL50) and the chronic effects based on body length, head width, and cumulative emergence. The results obtained in the acute effect tests indicated that the active chlorine of Ca(ClO)2 is 14 fold more toxic than PAA to C. xanthus. In sublethal evaluations, the active chlorine of Ca(ClO)2 presented higher toxicity than PAA in terms of percentage emergence, body development, and head width. In general, the results showed lower PAA toxicity relative to the active chlorine of Ca(ClO)2, demonstrating that PAA is a promising substitute for chlorinated disinfectants. In addition, the study facilitates the establishment of reference values for the safe release of effluents treated with PAA into water bodies.

Assuntos