RESUMEN

In the present study, pyroligneous acid, also known as wood vinegar, has been employed as reducing and stabilizing agent in the synthesis of silver nanoparticles (AgNPs) anchored on nanocellulose (NC). The idea is to confer the latter bactericidal properties for its typical uses such as in cosmetics and food-packing. It has been demonstrated that AgNPs can be directly produced onto NC in one-pot fashion while dramatically enhancing the kinetics of AgNPs synthesis (2 h for reaction completion) in comparison to the NC-less counterpart (10 days for reaction completion). Furthermore, NC allowed for a narrower size distribution of AgNPs. NC-supported and non-supported AgNPs had sizes of 5.1 ± 1.6 nm and 16.7 ± 4.62 nm, respectively. Immortalized human keratinocytes (HaCat) cells were then employed as model to evaluate the cytotoxicity of the AgNPs-NC compound. The latter was found not to impact cell proliferation at any formulation, while decreasing the viability by only 6.8% after 72 h. This study contributes to the development of more environmentally benign routes to produce nanomaterials and to the understanding of their impact on cells.

Asunto(s)

Supervivencia Celular , Celulosa , Células HaCaT , Nanopartículas del Metal , Plata , Humanos , Plata/química , Nanopartículas del Metal/química , Celulosa/química , Celulosa/farmacología , Supervivencia Celular/efectos de los fármacos , Queratinocitos/efectos de los fármacos , Queratinocitos/citología , Tamaño de la Partícula , Proliferación Celular/efectos de los fármacos , Ácido Acético/química , Ácido Acético/farmacología

RESUMEN

Drosophila suzukii (Matsumura) is an exotic pest of economic importance that affects several soft-skinned fruits in Mexico. Previously, we found that yellow or yellow-green rectangular cards inside a transparent trap baited with attractants improved D. suzukii capture. In this study, we evaluated the influence of rectangular cards with different yellow shades inside a transparent multi-hole trap baited with apple cider vinegar (ACV) on D. suzukii capture in the field. Second, we tested whether ACV-baited traps with cards of other geometric shapes affected D. suzukii catches compared to traps with rectangular cards. Third, we evaluated the effects of commercial lures combined with a more efficient visual stimulus from previous experiments on trapping D. suzukii flies. We found that ACV-baited traps plus a yellow-shaded rectangle card with 67% reflectance at a 549.74 nm dominant wavelength captured more flies than ACV-baited traps with yellow rectangle cards with a higher reflectance. Overall, ACV-baited traps with rectangles and squares caught more flies than did ACV-baited traps without visual stimuli. The traps baited with SuzukiiLURE-Max, ACV and Z-Kinol plus yellow rectangles caught 57, 70 and 101% more flies, respectively, than the traps baited with the lure but without a visual stimulus.

Asunto(s)

Drosophila , Control de Insectos , Animales , Drosophila/fisiología , Control de Insectos/instrumentación , Control de Insectos/métodos , Feromonas/farmacología , Femenino , Estimulación Luminosa , México , Ácido Acético/farmacología , Masculino

RESUMEN

Apis mellifera is an important pollinator that has a prominent impact on crops' ecological balance. Beekeeping provides us with more valuable products like honey, pollen, propolis, beeswax, and royal jelly. The ongoing era demands more scientific and environment-friendly strategies to improve the beekeeping sector internationally. Nowadays, the use of synbiotics (a combination of probiotics and prebiotics) has been declared as the need of the hour. However, little bit studies have been carried out in this regard. To improve the beekeeping sector in Pakistan, a study was designed to exploration of probiotic and organic acids on bee tissue ileum (small intestine). 108 Colony forming units (C.F.Us) of Bacillus clausii and Lactobacillus brevis were provided with and without mixing in 1.96% acetic acid, 2.91% acetic acid, and 2.99% lactic acid to caged worker bees under controlled laboratory conditions. The provision did not affect the intestine harmfully. The mean intestinal lumen diameters (µm2) were 133.33 ± 8.82, 63.33 ± 3.33, 186.67 ± 72.19, 250.00 ± 28.87, 166.67 ± 17.64, 193.33 ± 46.31, and 140.00 ± 61.10 in experiments (1, 2, 3, 5, and 6 respectively) compared to control's 113.33 ± 38.44. Worker bees with better digestion conditions prove honeybee's health and efficiency.

Asunto(s)

Probióticos , Animales , Abejas , Ácidos , Apicultura , Ácido Acético/farmacología , Intestinos

RESUMEN

Microbial resistance to drugs is a public health problem; therefore, there is a search for alternatives to replace conventional products with natural agents. One of the potential antimicrobial agents is wood vinegar derived from the carbonization of lignocellulosic raw materials. The objectives of the present work were to evaluate the antibacterial and antifungal action of two kinds of wood vinegar (WV), one of Eucalyptus urograndis wood and another of Bambusa vulgaris biomass, and determine their chemical profile. The antimicrobial effect was assessed against Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella enteritidis, Escherichia coli, Streptococcus agalactiae, and Candida albicans. The minimum inhibitory concentration and the minimum bactericidal and fungicidal concentrations were determined. Micrographs of the microorganisms before and after exposure to both kinds of wood vinegar were obtained by scanning electron microscopy. The chemical profile of the eucalyptus and bamboo vinegar was carried out by gas chromatography and mass spectrometry (GC/MS). Both types of WV presented significant antimicrobial activity, with the bamboo one having a higher efficiency. Both studied pyroligneous extracts seem promising for developing natural antimicrobials due to their efficiency against pathogens. GC/MS analyses demonstrated that the chemical profiles of both kinds of WV were similar but with some significant differences. The major component of the eucalyptus vinegar was furfural (17.2%), while the bamboo WV was phenol (15.3%). Several compounds in both WVs have proven antimicrobial activity, such as acetic acid, furfural, phenol, cresols, guaiacol, and xylenols. Together, they are the major in the chemical composition of the organic fraction of both WVs. Bamboo vinegar had a more expressive content of organic acids. Micrographs of microorganisms taken after exposure to both kinds of wood vinegar displayed several cell modifications. The potential of both types of wood vinegar as a basis for natural antimicrobial products seems feasible due to their proven effect on inhibiting the microorganisms' growth assessed in this experiment.

Asunto(s)

Antiinfecciosos , Bambusa , Eucalyptus , Ácido Acético/farmacología , Furaldehído , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Fenoles/análisis

RESUMEN

SUMMARY: The aim of the present in vitro study is to visualize dentin to get an in-depth knowledge of the nature of dentin that could provide useful information regarding conditioning dentinal substrate when treating dentinal lesions. Forty-nine extracted human third molars were obtained and prepared to produce artificial dentinal lesions through demineralizing with acetic acid for 7 and 14 days, or lactic acid for 7 days. The teeth were divided into groups and treated with either NaOCl, pepsin, trypsin, or phosphoric acid. To obtain information on the morphology of the treated dentinal surfaces, all samples were visualized under high resolution field emission scanning electron microscope. With high magnification reaching x50000 dentin was clearly visualized together with its constitutes. The effect of various demineralization approaches and various treatment protocols were demonstrated clearly. The relationship between the conditioning procedure steps and the subsequent bond strength was discussed. To our best knowledge, there is no previous clear highly magnified scanning electron microscope images for dentin, and dentinal components and constitutes with and without various treatments. The current in vitro study suggests the complexity nature of dentin as a substrate that should be treated carefully especially with technique sensitive procedures such as adhesive restorations.

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El objetivo del presente estudio in vitro fue visualizar la dentina para obtener un conocimiento completo de la naturaleza de ella lo que podría proporcionar información útil sobre el acondicionamiento del sustrato dentinario en el tratamiento de lesiones dentinarias. Se obtuvieron 49 terceros molares humanos extraídos y se prepararon para producir lesiones dentinales artificiales mediante desmineralización con ácido acético por 7 y 14 días, o ácido láctico por 7 días. Los dientes se dividieron en grupos y se trataron con NaOCl, pepsina, tripsina o ácido fosfórico. Para obtener información sobre la morfología de las superficies dentinarias tratadas, todas las muestras se visualizaron bajo un microscopio electrónico de barrido de emisión de campo de alta resolución. Con un gran aumento que alcanzó x50000, la dentina se visualizó claramente junto con sus componentes. Se demostró el efecto de varios enfoques de desmineralización y varios protocolos de tratamiento. Se discutió la relación entre los pasos del procedimiento de acondicionamiento y la subsiguiente fuerza de unión. Hasta donde sabemos, no hay imágenes claras previas de microscopio electrónico de barrido altamente ampliadas para la dentina y los componentes y constituyentes de la dentina con y sin diferentes tratamientos. El estudio in vitro actual sugiere la naturaleza compleja de la dentina como sustrato que debe tratarse con cuidado, especialmente en los procedimientos sensibles a la técnica, tal como las restauraciones adhesivas.

Asunto(s)

Humanos , Desmineralización Dental/inducido químicamente , Dentina/efectos de los fármacos , Dentina/ultraestructura , Hipoclorito de Sodio , Microscopía Electrónica de Rastreo , Tripsina , Pepsina A , Ácido Acético/farmacología , Ácido Láctico/farmacología

RESUMEN

Aedes aegypti is closely related to human behavior that allows its establishment through the accumulation of urban solid waste where it lays resistant eggs. Generally, adulticides and larvicides are applied in excess, without ovicidal alternatives, and some household products can help reduce the abundance of quiescent eggs in breeding sites by affecting the viability of eggs. A community involved in prevention and control is one of the most effective strategies for adequate vector management. In this investigation, new alternative strategies for the control of Ae. aegypti are assessed, valuing in laboratory the eggs' response to diverse household products. Susceptibility to different doses of bleach, oil, salt, sodium bicarbonate, vinegar, coffee, garlic, peroxide, and alcohol was measured, as well as its duration over time. New home products were found as alternative ovicidal method. Bleach and sunflower oil had an ovicidal effect at their maximum doses and at almost all of the evaluation times. In contrast, vinegar and coffee had no ovicidal effect at any time, turning out to be stimulators of hatching in the laboratory. These alternative and complementary applications could optimize the surveillance and control of Ae. aegypti in the area, allowing new approaches to reduce populations by eliminating eggs on human microhabitats.

Asunto(s)

Aedes , Dengue , Animales , Humanos , Aedes/fisiología , Argentina , Ácido Acético/farmacología , Café , Mosquitos Vectores , Larva

RESUMEN

The production of yeast oil from lignocellulosic biomasses is impaired by inhibitors formed during the pretreatment step, mainly acetic acid. Herein, we applied Adaptive Laboratory Evolution (ALE) to select three Acetic acid Tolerant Strains (ATS) of P. laurentii UFV-1. Different phenotypes emerged alongside evolution. The ATS II presented trade-offs in the absence of acetic acid, suggesting that it displays a specialized phenotype of tolerance to growth on organic acids. On the other hand, ATS I and ATS III presented phenotypes associated with the behavior of generalists. ATS I was considered the most promising evolved strain as it displayed the oleaginous phenotype in all conditions tested. Thus, we applied whole-genome sequencing to detect the mutations that emerged in this strain during the ALE. We found alterations in genes encoding proteins involved in different cellular functions, including multidrug resistance (MDR) transporters, energy metabolism, detoxification, coenzyme recycling, and cell envelope remodeling. To evaluate acetic acid stress responses, both parental and ATS I strains were cultivated in chemostat mode in the absence and presence of acetic acid. In contrast to ATS I, the parental strain presented alterations in the cell envelope and cell size under acetic acid stress conditions. Furthermore, the parental strain and the ATS I presented differences regarding acetic acid assimilation. Contrary to the parental strain, the ATS I displayed an increase in unsaturated fatty acid content irrespective of acetic acid stress, which might be related to improved tolerance to acetic acid. Altogether, these results provided insights into the mechanisms involved with the acetic acid tolerance displayed by ATS I and the responses of P. laurentii to this stressful condition.

Asunto(s)

Ácido Acético , Saccharomyces cerevisiae , Ácido Acético/farmacología , Ácido Acético/metabolismo , Saccharomyces cerevisiae/genética , Fenotipo , Proteínas de Transporte de Membrana/genética

RESUMEN

Chlorinated compounds are usually applied in vegetable sanitization, but there are concerns about their application. Thus, this study aimed to evaluate ultrasound (50 kHz), acetic acid (1000; 2000 mg/L), and peracetic acid (20 mg/L) and their combination as alternative treatments to 200 mg/L sodium dichloroisocyanurate. The overall microbial, physicochemical, and nutritional quality of kale stored at 7 °C were assessed. The impact on Salmonella enterica Typhimurium was verified by plate-counting and scanning electron microscopy. Ultrasound combined with peracetic acid exhibited higher reductions in aerobic mesophiles, molds and yeasts, and coliforms at 35 °C (2.6; 2.4; 2.6 log CFU/g, respectively). Microbial counts remained stable during storage. The highest reduction in Salmonella occurred with the combination of ultrasound and acetic acid at 1000 mg/L and acetic acid at 2000 mg/L (2.8; 3.8 log CFU/g, respectively). No synergistic effect was observed with the combination of treatments. The cellular morphology of the pathogen altered after combinations of ultrasound and acetic acid at 2000 mg/L and peracetic acid. No changes in titratable total acidity, mass loss, vitamin C, or total phenolic compounds occurred. Alternative treatments presented equal to or greater efficacies than chlorinated compounds, so they could potentially be used for the decontamination of kale.

Asunto(s)

Brassica , Compuestos de Cloro , Desinfectantes , Ácido Peracético/farmacología , Ácido Acético/farmacología , Desinfectantes/farmacología , Descontaminación , Desinfección , Microbiología de Alimentos , Recuento de Colonia Microbiana , Salmonella typhimurium , Ácido Ascórbico/farmacología , Cloro/farmacología , Cloro/química , Manipulación de Alimentos

RESUMEN

Organic acids and their salts are usually the first choice in the bread industry to restrict fungal spoilage, but their efficacy is pH-dependent and spoilage by fungi remains as a common threat. Therefore, this study aimed to evaluate the susceptibility of spoilage fungi of bakery products to acetic, sorbic, and propionic acids at different pH. Penicillium roqueforti, Penicilium paneum, Aspergillus pseudoglaucus, Aspergillus montevidensis and Hyphopichia burtonii strains isolated from spoiled products had their minimum inhibitory concentration (MIC) defined by macrodilution. The concentrations tested were: (i) sorbic acid up to 32 mM; (ii) propionic acid up to 1024 mM and (iii) acetic acid up to 800 mM with pH adjusted in 4.5, 5.0, 5.0 and 6.0 after setting the agent concentration. The lowest MICs for all agents were obtained at pH 4.5, usually doubling with every 0.5 pH increase. P. roqueforti strains isolated from spoiled products were the most resistant to all tested preservatives; while strains of the related species P. paneum, showed similar tolerance to acetic and propionic acids but was double more susceptible to sorbic acid. Strains of A. pseudoglaucus and A. montevidensis were indistinctly susceptible to the preservatives and were the most susceptible species to propionic and acetic acids. H. burtonii strains demonstrated the most variable behaviour in comparison to the other strains being the most susceptible to sorbic acid, were like Aspergillus strains regarding propionic acid, but tolerate well acetic acid. Propionic acid concentrations usually allowed in baked goods are lower than the concentrations required to inhibit the most tolerant isolates tested in this study. The same is true for sorbic acid at higher pH levels. Spoilage species of bakery ware presents a distinct susceptibility profile to the preservatives commonly used in this sector, but the high tolerance observed is a cause of concern.

Asunto(s)

Conservantes de Alimentos , Ácido Sórbico , Ácido Acético/farmacología , Ácidos/farmacología , Pan/microbiología , Conservantes de Alimentos/farmacología , Hongos , Concentración de Iones de Hidrógeno , Propionatos/farmacología , Ácido Sórbico/farmacología

RESUMEN

INTRODUCTION: Acetic acid (AA) has been commonly used in medicine as an antiseptic agent for the past 6000 years. This study evaluated the antibacterial effect of AA during an outbreak in an intensive care unit (ICU) facility in Baja California Sur, México. METHODOLOGY: Thirty-five environmental samples were collected, subsequently, disinfection with AA (4%) was performed, and two days later the same areas were sampled inside the ICU facility. Carbapenem-resistant A. baumannii (CRAB) was detected with loop-mediated isothermal amplification assay (Garciglia-Mercado et al. companion paper), targeting blaOXA-23-like, blaOXA-24-like, blaOXA-51-like, blaOXA-58-like, blaIMP and blaVIM genes. CRAB isolates before and after disinfection were compared by PFGE. RESULTS: Eighteen (54.5%) and five (14.3%) of thirty-five environmental samples were identified as Acinetobacter baumannii before and after disinfection, respectively, showing a significant decrease of 85.7% (p < 0.05) both by Loop-mediated isothermal amplification (LAMP) and polymerase chain reaction (PCR). Furthermore, the presence of blaOXA-23-like and blaOXA-58-like genes significantly decreased (p < 0.05) both by LAMP and PCR methods. PFGE genotype showed high similarity among CRAB isolates before and after disinfection, suggesting wide clonal dissemination in the ICU facility. CONCLUSIONS: This study demonstrated the novel application of AA with the LAMP assays developed for detecting CRAB. AA promises to be a cheap and efficacious disinfectant alternative to both developed and especially developing countries, preventing the spread of this organism in the environment and to other susceptible patients in health care settings.

Asunto(s)

Ácido Acético/uso terapéutico , Infecciones por Acinetobacter/microbiología , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Ácido Acético/farmacología , Acinetobacter baumannii/aislamiento & purificación , Antibacterianos/farmacología , Humanos , Unidades de Cuidados Intensivos , México , Pruebas de Sensibilidad Microbiana , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico

RESUMEN

Twelve 7-chloroquinoline derivatives were designed and synthesized using the principle of molecular hybridization through the coupling of 2-[2-(7-chloroquinolin-4-ylthio)-4-methylthiazol-5-yl]acetic acid 1 with various benzoyl hydrazines 2a-l. The synthetic compounds were tested as antimalarials. Some of them showed an efficient in vitro activity as inhibitors of ß-hematin formation and an in vivo activity in a murine model, resulting in compounds 8 and 9 as the most active ones with IC50 values of 0.65 ± 0.09 and 0.64 ± 0.16 µM, respectively. The effects of the compounds on the cell viability, cell cycle, and apoptosis induction of A549 and MCF-7 cancer cell lines were also examined. Our data showed that compounds 6 and 12 were the most active agents, decreasing the cell viability of MCF-7 cells with IC50 values of 15.41 and 12.99 µM, respectively. None of the compounds analyzed significantly affected the viability of peripheral blood mononuclear cells. Also, significant induction of apoptosis was observed when both cancer cell lines were incubated with compounds 6 and 12. In MCF-7 cells, treatment with these compounds led to cell cycle arrest in the G0/G1 phase. The results obtained suggest that these structures may be useful in developing new therapies for malaria and cancer treatment.

Asunto(s)

Antimaláricos/farmacología , Antineoplásicos/farmacología , Hidrazinas/farmacología , Quinolinas/farmacología , Células A549 , Ácido Acético/síntesis química , Ácido Acético/química , Ácido Acético/farmacología , Animales , Antimaláricos/síntesis química , Antimaláricos/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Humanos , Hidrazinas/síntesis química , Hidrazinas/química , Concentración 50 Inhibidora , Células MCF-7 , Malaria/tratamiento farmacológico , Masculino , Ratones , Ratones Endogámicos BALB C , Quinolinas/síntesis química , Quinolinas/química , Relación Estructura-Actividad , Tiazoles/síntesis química , Tiazoles/química , Tiazoles/farmacología

RESUMEN

Taxifolin (3,5,7,3,4-pentahydroxy flavanone or dihydroquercetin, Tax) was identified as a gastroprotective compound and a gastroadhesive formulation was recently developed to prolong its residence time and release in the stomach. So, the gastric healing effectiveness of Tax and gastro-mucoadhesive microparticles containing Tax (MPTax) against the acetic acid induced-gastric ulcer in rats was investigated in this study. Moreover, the interactions between Tax and H+/K+-ATPase were investigated in silico, and its anti- H. pylori activity was determined in vitro. The oral treatment with MPTax (81.37 mg/kg, containing 12.29% of Tax) twice a day for seven days reduced the ulcer area by 63%, compared to vehicle-treated group (Veh: 91.9 ± 10.3 mm2). Tax (10 mg/kg, p.o) reduced the ulcer by 40% but with a p = 0.07 versus Veh group. Histological analysis confirmed these effects. Tax and MPTax increased the gastric mucin amount, reduced the myeloperoxidase activity, and increased the glutathione reduced content at ulcer site. However, only MPTax decreased the lipoperoxide accumulation at ulcer site. Besides, Tax and MPTax normalize the catalase and glutathione S-transferase activity. Tax showed reversible interaction with H+/K+-ATPase in silico and its anti-H. pylori effects was confirmed (MIC = 625 µg/mL). These results suggest that the antiulcer property of Tax involves the strengthening of the gastric protective factors in parallel to its inhibitory interaction with H+/K+-ATPase and H. pylori. Considering that ulcer healing action displayed by Tax was favored by gastroadhesive microparticles, this approach seems to be promising for its oral delivery to treat acid-peptic diseases.

Asunto(s)

Adhesivos/farmacología , Helicobacter pylori/efectos de los fármacos , Bombas de Protones/fisiología , Quercetina/análogos & derivados , Estómago/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos , Ácido Acético/farmacología , Animales , Antiulcerosos/farmacología , Antioxidantes/metabolismo , Catalasa/metabolismo , Simulación por Computador , Femenino , Mucinas Gástricas/metabolismo , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/metabolismo , ATPasa Intercambiadora de Hidrógeno-Potásio/metabolismo , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/metabolismo , Infecciones por Helicobacter/microbiología , Fitoterapia/métodos , Extractos Vegetales/farmacología , Quercetina/fisiología , Ratas , Ratas Wistar , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/tratamiento farmacológico , Úlcera Gástrica/metabolismo , Úlcera Gástrica/microbiología

RESUMEN

Neutrophils represent the first line of host cellular defense against various pathogens. The most recently described microbicidal mechanism of these cells is the release of neutrophil extracellular traps (NET). Currently, a wide range of chemical and biological stimuli are known to induce this response; however, the effect of short-chain fatty acids (SCFAs) on the induction of NET is still unknown. SCFAs are produced mainly by bacterial fermentation of dietary fiber and are found in host tissues and blood. This study aimed to determine whether physiological levels of SCFAs can induce the formation of NET. Previously reported concentrations of SCFAs (as found in the colonic lumen and peripheral blood in postprandial and basal states) were used to stimulate the neutrophils. In order to determine the signaling pathway utilized by SCFAs, we tested the inhibition of the Free Fatty Acid 2 Receptor (FFA2R) expressed in neutrophils using CATPB, the inhibitor of FFA2R, genistein, an inhibitor of the downstream Gα/q11 proteins and DPI, an inhibitor of the NADPH oxidase complex. The SCFAs at colonic intestinal lumen concentrations were able to induce the formation of NET, and when tested at concentrations found in the peripheral blood, only acetic acid at 100 µM (fasting equivalent) and 700 µM (postprandial equivalent) was found to induce the formation of NET. The administration of the competitive inhibitor against the receptor or blockade of relevant G protein signaling and the inhibition of NADPH oxidase complex decreased NET release. SCFAs stimulate NET formation in vitro and this effect is mediated, in part, by the FFA2R.

Asunto(s)

Ácido Acético/farmacología , Trampas Extracelulares/metabolismo , Ácidos Grasos Volátiles/metabolismo , Neutrófilos/metabolismo , Trampas Extracelulares/efectos de los fármacos , Ácidos Grasos Volátiles/farmacología , Humanos , Concentración de Iones de Hidrógeno , Neutrófilos/efectos de los fármacos , Receptores de Superficie Celular/metabolismo

RESUMEN

This work evaluated the application of organic acids (acetic and peracetic acid) and ultrasound as alternative sanitization methods for improving the microbiological and physicochemical qualities of strawberries. A reduction of up to 2.48 log CFU/g aerobic mesophiles and between 0.89 and 1.45 log CFU/g coliforms at 35 °C was found. For molds and yeasts, significant differences occurred with different treatments and storage time (p < 0.05). Ultrasound treatments in combination with peracetic acid and acetic acid allowed a decimal reduction in molds and yeasts (p < 0.05). All evaluated treatments promoted a significant reduction in the Escherichia coli count (p < 0.05). Scanning electron microscopy revealed fragmented E. coli cells due to treatment with acetic acid and ultrasound. Storage time significantly affected pH, total titratable acidity, total soluble solids and the ratio of the total titratable acidity to the total soluble solids (p < 0.05). Anthocyanin content did not change with treatment or time and generally averaged 13.47 mg anthocyanin/100 g of strawberries on fresh matter. Mass loss was not significantly affected by the applied treatments (p > 0.05). The combination of ultrasound and peracetic acid may be an alternative to chlorine-based compounds to ensure microbiological safety without causing significant changes in the physicochemical characteristics of strawberries.

Asunto(s)

Ácido Acético/química , Desinfección , Microbiología de Alimentos , Fragaria , Ácido Peracético/química , Ondas Ultrasónicas , Ácido Acético/farmacología , Fenómenos Químicos , Desinfectantes/química , Desinfectantes/farmacología , Desinfección/métodos , Microbiología de Alimentos/métodos , Calidad de los Alimentos , Fragaria/microbiología , Microbiota , Ácido Peracético/farmacología

RESUMEN

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.

Asunto(s)

Adhesión Bacteriana/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Desinfectantes/farmacología , Listeria monocytogenes/efectos de los fármacos , Sales (Química)/farmacología , Cloruro de Sodio/farmacología , Ácido Acético/farmacología , Manipulación de Alimentos , Microbiología de Alimentos , Industria de Procesamiento de Alimentos , Guanidinas/farmacología , Peróxido de Hidrógeno/farmacología , Listeria monocytogenes/aislamiento & purificación , Listeria monocytogenes/metabolismo , Listeriosis/prevención & control , Carne/microbiología , Pruebas de Sensibilidad Microbiana , Ácido Peracético/farmacología , Compuestos de Amonio Cuaternario/farmacología

RESUMEN

Various animal models, especially rodents, are used to study pain, due to the difficulty of studying it in humans. Many drugs that produce analgesia have been studied and there is evidence among which NSAIDs deserve to be highlighted. Dexketoprofen (DEX) provides a broad antinociceptive profile in different types of pain; therefore, this study was designed to evaluate the profile of antinociceptive potency in mice. Analgesic activity was evaluated using the acetic acid abdominal constriction test (writhing test), a chemical model of visceral pain. Dose-response curves for i.p. DEX administration (1, 3, 10, 30 and 100 mg/kg), using at least six mice in each of at least five doses, was obtained before and 30 min after pre-treatment with different pharmacological agents. Pretreatment of the mice with opioid receptor antagonists was not effective; however, the serotonin receptor antagonist and nitric oxide synthase inhibitor produce a significant increase in DEX-induced antinociception. The data from the present study shows that DEX produces antinociception in the chemical twisting test of mice, which is explained with difficulty by the simple inhibition of COX. This effect appears to be mediated by other mechanisms in which the contribution of the NO and 5-HT pathways has an important effect on DEXinduced antinociception.

Asunto(s)

Cetoprofeno/análogos & derivados , Receptores Opioides/genética , Receptores de Serotonina/genética , Trometamina/farmacología , Dolor Visceral/tratamiento farmacológico , Ácido Acético/farmacología , Analgesia/métodos , Analgésicos/farmacología , Animales , Antiinflamatorios no Esteroideos/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Cetoprofeno/farmacología , Ratones , Antagonistas de Narcóticos/farmacología , Óxido Nítrico/genética , Serotonina/genética , Antagonistas de la Serotonina/farmacología , Dolor Visceral/genética , Dolor Visceral/patología

RESUMEN

Docetaxel-loaded acetic acid conjugated Cordyceps sinensis polysaccharide (DTX-AA-CSP) nanoparticles were prepared through dialysis and their release rates in vitro, particle sizes, zeta potentials, drug loading capacities, and encapsulation efficiencies were characterized for the synthesis of AA-modified CSPs from traditional Chinese medicine Cordyceps sinensis (Berk.) Sacc. Then, the AA-modified CSPs were characterized by 1H-NMR and FT-IR. Furthermore, the biocompatibility of the delivery carrier (AA-CSP nanoparticles) was assessed on human umbilical vein endothelial cells. In vitro antitumor activity studies on DTX-AA-CSP nanoparticles were conducted on the human liver (HepG2) and colon cancer cells (SW480). The DTX-AA-CSP nanoparticles were spherical and had an average size of 98.91±0.29 nm and zeta potential within the −19.75±1.13 mV. The encapsulation efficiency and loading capacity were 80.95%±0.43% and 8.09%±0.04%, respectively. In vitro, DTX from the DTX-AA-CSP nanoparticles exhibited a sustained release, and the anticancer activities of DTX-AA-CSP nanoparticles against SW480 and HepG2 were significantly higher than those of marketed docetaxel injection (Taxotere®) in nearly all the tested concentrations. The AA-CSP nanoparticles showed good biocompatibility. This study provided a promising biocompatible delivery system for carrying antitumor drugs for cancer therapy

Asunto(s)

Polisacáridos/efectos adversos , Ácido Acético/farmacología , Cordyceps/clasificación , Nanopartículas/análisis , Técnicas In Vitro/métodos , Preparaciones Farmacéuticas/análisis , Sistemas de Liberación de Medicamentos/instrumentación , Neoplasias del Colon/patología , Espectroscopía de Protones por Resonancia Magnética/métodos , Antineoplásicos

RESUMEN

This study evaluated whether the pre-exposure (24, 48 and 72 h) to sublethal conditions caused by acetic acid (AA), lactic acid (LA), sodium chloride (NaCl) or potassium chloride (KCl) could induce increased cross-tolerance to the essential oils from Origanum vulgare L. (OVEO) and Rosmarinus officinalis L. (ROEO) in different Listeria monocytogenes strains. Damage to membrane integrity, membrane potential, enzymatic activity and efflux activity in L. monocytogenes cells pre-exposed (24 h) to AA or NaCl and further treated with OVEO or ROEO (8 and 24 h) were investigated using flow cytometry (FC). Results of minimum inhibitory concentration (MIC) modulation test showed that pre-exposure to sublethal conditions caused by organic acids or salts increased cross-tolerance only to ROEO, since MIC of ROEO increased up to 4.8-fold against pre-exposed cells. Otherwise, MIC of OVEO against these pre-exposed cells was up to ten-fold lower than that observed against not pre-exposed cells, indicating no increase in cross-tolerance. Bacterial survival assays showed that ROEO only decreased the counts over time of cells not pre-exposed to organic acids or salts, while OVEO decreased similarly or more the counts of pre-exposed cells compared to not pre-exposed cells. Results of FC analysis showed that all measured functions in L. monocytogenes cells pre-exposed to AA or NaCl and treated with OVEO or ROEO were affected, although with different intensities. These data indicate that exposure to sublethal conditions imposed by organic acids or salts could result in a phenotype of increased cross-tolerance to ROEO but not to OVEO in L. monocytogenes.

Asunto(s)

Listeria monocytogenes/efectos de los fármacos , Aceites Volátiles/farmacología , Origanum/química , Rosmarinus/química , Sales (Química)/farmacología , Ácido Acético/farmacología , Ciclohexanoles/farmacología , Microbiología de Alimentos , Conservantes de Alimentos/farmacología , Listeria monocytogenes/fisiología , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Cloruro de Potasio/farmacología , Cloruro de Sodio/farmacología , Estrés Fisiológico

RESUMEN

Chronic stress exposure commonly increases adrenals weight and changes their morphology. This study aimed to compare four methods to delimitate the cortical and medullary layers of adrenals glands in Nelore bulls. Fresh adrenals did not present differentiation between layers. Then, frozen adrenals were distributed in plastics bags with fixative Bouin (G1), 96ºGL ethylic alcohol (G2), 10% formaldehyde (G3), or 2.5% glutaraldehyde (G4). After 12 hours of fixation, the G1 adrenal glands did not show the entire cortical layer marked by Bouin's solution. For G2 and G3 there was a poor contrast, while for G4 there was a reasonable contrast. After 24 hours of fixation, G1 had an excellent contrast between layers, while G2 and G4 had a reasonable contrast and G3 a very bad contrast. After 48 hours it was difficult to differentiate cortical and medullar layers for G1; for Group 2 we get a reasonable contrast; and for G3 the contrast was bad. For G4 the contrast was not as sharp due to the medulla became dark. It was concluded that fixation of adrenals must be done in Bouin's solution for 24 hours to obtain an effective evaluation of the adrenals' morphometry.

Asunto(s)

Ácido Acético/farmacología , Glándulas Suprarrenales/anatomía & histología , Glándulas Suprarrenales/efectos de los fármacos , Etanol/farmacología , Fijadores/farmacología , Formaldehído/farmacología , Glutaral/farmacología , Picratos/farmacología , Animales , Bovinos

RESUMEN

This quantitative and qualitative study aimed to evaluate the level of fungal contamination in computer keyboards from an Integrated Health Center (IHC) at Piauí, Brazil, and to evaluate the efficacy of 50% sodium bicarbonate and 50% alcoholic vinegar solutions to eliminate these microorganisms. Ten keyboards from six sectors of the IHC were chosen randomly, and the collection was performed in three situations: (i) before of disinfection, (ii) after disinfection with solution of sodium bicarbonate, and (iii) after disinfection with solution of alcoholic vinegar. Samples were inoculated in Petri dishes with dextrose agar potato plus chloramphenicol and incubated at room temperature for 72 h. All keyboards were contaminated with opportunistic fungi, with Cladosporium cladosporioides (29.4%) being the most frequent species, followed by Curvularia lunata (17.6%) and Aspergillus niger, Alternaria alternata, and Curvularia clavata with 11.8% each. The two solutions were proven to be efficient in eliminating fungal contamination; however, the sodium bicarbonate solution caused esthetic damages in keyboards. In addition, this study is the first report of the antifungal activity of alcoholic vinegar in filamentous fungi. Based on our findings, we suggest a daily disinfection of keyboards with a 50% vinegar solution plus adequate hygiene from the hands of professionals before and after the use of the computer and its annexes, as key actions to reduce nosocomial infections, particularly in economically disadvantaged countries.

Asunto(s)

Ácido Acético/farmacología , Alternaria/efectos de los fármacos , Antifúngicos/farmacología , Aspergillus niger/efectos de los fármacos , Cladosporium/efectos de los fármacos , Desinfectantes/farmacología , Desinfección/métodos , Control de Infecciones/métodos , Bicarbonato de Sodio/farmacología , Alternaria/aislamiento & purificación , Aspergillus niger/aislamiento & purificación , Brasil , Cladosporium/aislamiento & purificación , Computadores , Monitoreo del Ambiente , Humanos