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OBJECTIVE: To investigate the effect of three different doses of oral pregabalin on minimum alveolar concentration of isoflurane (MACISO) in cats. STUDY DESIGN: Prospective, randomized, placebo-controlled, blinded, crossover trial. ANIMALS: A group of eight healthy adult cats aged 24-48 months. METHODS: Cats were randomly assigned to three oral doses of pregabalin (low dose: 2.5 mg kg-1, medium dose: 5 mg kg-1, high dose: 10 mg kg-1) or placebo 2 hours before MACISO determination, with the multiple treatments administered with a minimum 7 day washout period. Anesthesia was induced and maintained with isoflurane in oxygen until endotracheal intubation was achieved, and maintained with isoflurane with volume-controlled ventilation. MACISO was determined in triplicate using the bracketing technique and tail clamp method 120 minutes after pregabalin or placebo administration. Physiologic variables (including heart rate and blood pressure) recorded during MACISO determination were averaged and compared between the pregabalin and placebo treatments. One-way analysis of variance and the Friedman test were used to assess the difference for normally and non-normally distributed data, respectively. The Tukey test was used as a post hoc analysis. Values of p < 0.05 were considered significant. RESULTS: The MACISO with the medium- and high-dose pregabalin treatments were 1.33 ± 0.21% and 1.23 ± 0.17%, respectively. These were significantly lower than MACISO after placebo treatment (1.62 ± 0.13%; p = 0.014, p < 0.001, respectively), representing a decrease of 18 ± 9% and 24 ± 6%. The mean plasma pregabalin concentration was negatively correlated with MACISO values. Physiologic variables did not differ significantly between treatments. CONCLUSIONS AND CLINICAL RELEVANCE: Doses of 5 or 10 mg kg-1 pregabalin, administered orally 2 hours before determining MACISO, had a significant isoflurane-sparing effect in cats.
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Anestésicos por Inhalación , Estudios Cruzados , Isoflurano , Pregabalina , Alveolos Pulmonares , Animales , Gatos , Femenino , Masculino , Administración Oral , Analgésicos/administración & dosificación , Analgésicos/farmacología , Analgésicos/farmacocinética , Anestesia por Inhalación/veterinaria , Anestésicos por Inhalación/administración & dosificación , Anestésicos por Inhalación/farmacocinética , Anestésicos por Inhalación/farmacología , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Isoflurano/administración & dosificación , Isoflurano/farmacocinética , Pregabalina/administración & dosificación , Pregabalina/farmacología , Alveolos Pulmonares/metabolismoRESUMEN
Sulfate radical (â¢SO4-)-based advanced oxidation processes are widely used for wastewater treatment. This study explored the potential use of UV/persulfate (UV/PS) system for the degradation of 17ß-estradiol (E2). The pH of the reaction system can affect the degradation rate of E2 by UV/PS and the optimum pH was 7.0; Br- and Cl- in water can promote the degradation rate, HCO3- has an inhibitory effect on the reaction, SO42- and cations (Na+, Mg2+, K+) have no effect on the degradation rate. The degradation of E2 by UV/PS was a mineralization process, with the mineralization rate reaching 90.97% at 8 h. E2 in the UV/PS system was mainly degraded by hydroxylation, deoxygenation, and hydrogenation. E2 reaction sites were mainly located on benzene rings, mainly carbonylation on quinary rings, and bond breakage between C10 and C5 resulted in the removal of benzene rings and carboxyl at C2 and C3 sites. In the presence of halogen ions, halogenated disinfection by-products were not formed in the degradation process of E2 by UV/PS. E2 in the UV/PS system could inhibit the formation of bromate. The results of this study suggest that UV/PS is a safe and reliable method to degrade E2.
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Contaminantes Químicos del Agua , Purificación del Agua , Estradiol , Oxidación-Reducción , Sulfatos , Rayos Ultravioleta , Agua , Contaminantes Químicos del Agua/análisisRESUMEN
Seven popular fluoroquinolone antibiotics (FQs) in synthetic marine aquaculture water were subject to sodium hypochlorite (NaClO) disinfection scenario to investigate their reaction kinetics and transformation during chlorination. Reactivity of each FQ to NaClO was following the order of ofloxacin (OFL) > enrofloxacin (ENR) > lomefloxacin (LOM) > ciprofloxacin (CIP) ~ norfloxacin (NOR) >> pipemedic acid (PIP), while flumequine did not exhibit reactivity. The coexisting chlorine ions and sulfate ions in the water slightly facilitated the oxidation of FQs by NaClO, while humic acid was inhibitable to their degradation. The bromide ions promoted degradation of CIP and LOM, but restrained oxidation of OFL and ENR. By analysis of liquid chromatography with tandem mass spectrometry (LC-MS/MS), eight kinds of emerging brominated disinfection byproducts (Br-DBPs) caused by FQS were primarily identified in the chlorinated synthetic marine culture water. Through density functional theory calculation, the highest-occupied molecular orbital (HOMO) and the lowest-unoccupied molecular orbital (LUMO) characteristic as well as the charge distribution of the FQs were obtained to clarify transformation mechanisms. Their formation involved decarboxylation, ring-opening/closure, dealkylation and halogenation. Chlorine substitution occurred on the ortho-position of FQs's N4 and bromine substitution occurred on C8 position. The piperazine ring containing tertiary amine was comparatively stable, while this moiety with a secondary amine structure would break down during chlorination. Additionally, logKow and logBAF of transformation products were calculated by EPI-SuiteTM to analyze their bioaccumulation. The values indicated that Br-DBPs are easier to accumulate in the aquatic organism relative to their chloro-analogues and parent compounds.
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Contaminantes Químicos del Agua , Purificación del Agua , Antibacterianos , Bromuros , Cromatografía Liquida , Desinfección , Fluoroquinolonas , Halogenación , Cinética , Hipoclorito de Sodio , Espectrometría de Masas en Tándem , Agua , Contaminantes Químicos del Agua/análisisRESUMEN
The aim of this work was to evaluate the antibacterial activities and mode of action of sucrose monolaurate (SML) with a desirable purity, synthesized by Lipozyme TL IM-mediated transesterification in the novel ionic liquid, against four pathogenic bacteria including L. monocytogenes, B. subtilis, S. aureus, and E. coli. The antibacterial activity was determined by minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and the timeâ»kill assay. SML showed varying antibacterial activity against tested bacteria with MICs and MBCs of 2.5 and 20 mM for L. monocytogenes, 2.5 and 20 mM for B. subtilis, 10 and 40 mM for S. aureus, respectively. No dramatic inhibition was observed for E. coli at 80 mM SML. Mechanism of bacterial inactivation caused by SML was revealed through comprehensive factors including cell morphology, cellular lysis, membrane permeability, K⺠leakage, zeta potential, intracellular enzyme, and DNA assay. Results demonstrated that bacterial inactivation against Gram-positive bacteria was primarily induced by the pronounced damage to the cell membrane integrity. SML may interact with cytoplasmic membrane to disturb the regulation system of peptidoglycan hydrolase activities to degrade the peptidoglycan layer and form a hole in the layer. Then, the inside cytoplasmic membrane was blown out due to turgor pressure and the cytoplasmic materials inside leaked out. Leakage of intracellular enzyme to the supernatants implied that the cell membrane permeability was compromised. Consequently, the release of K⺠from the cytosol lead to the alterations of the zeta potential of cells, which would disturb the subcellular localization of some proteins, and thereby causing bacterial inactivation. Moreover, remarkable interaction with DNA was also observed. SML at sub-MIC inhibited biofilm formation by these bacteria.
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Antibacterianos/química , Catálisis , Infecciones/tratamiento farmacológico , Sacarosa/análogos & derivados , Antibacterianos/síntesis química , Antibacterianos/farmacología , Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/patogenicidad , Permeabilidad de la Membrana Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/patogenicidad , Humanos , Infecciones/microbiología , Lipasa/química , Listeria monocytogenes/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/patogenicidad , Sacarosa/química , Sacarosa/farmacologíaRESUMEN
OBJECTIVES: The aim of this study was to evaluate the efficacy of a single dose of oral pregabalin (PGB) for sedation and its impact on physiological and echocardiographic variables in healthy cats. METHODS: This study was a randomised, blinded, crossover trial. Eight cats were randomly assigned to receive PGB or placebo, with a 1-week washout period between each administration. Cats in the treatment group received oral PGB at varying doses (low dose: 2.5 mg/kg, medium dose: 5 mg/kg, high dose: 10 mg/kg). Systolic blood pressure (SBP), pulse rate (PR), respiratory rate (RR) and sedation score were measured at intervals of 30 mins after administration. Echocardiography was performed 120 mins after administration. RESULTS: Oral administration of PGB 2.5 mg/kg and 5 mg/kg significantly increased sedation scores starting at 150 mins, while 10 mg/kg PGB showed a significant increase in sedation scores starting at 120 mins compared with placebo. PGB 5 mg/kg and 10 mg/kg resulted in a significant reduction in SBP compared with placebo, with minimal impact on PR and RR. In addition, PGB 10 mg/kg resulted in significant changes in the peak velocity of late diastolic transmitral flow (A) and the ratio of peak velocity of early diastolic transmitral flow and A; however, these changes were of marginal clinical significance. CONCLUSIONS AND RELEVANCE: A single dose of oral PGB could cause mild to moderate sedation. Hypotension was more prevalent in the PGB 5 mg/kg and 10 mg/kg groups among the majority of cats, but it was less frequently observed in the PGB 2.5 mg/kg group.
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Estudios Cruzados , Ecocardiografía , Pregabalina , Animales , Gatos , Pregabalina/administración & dosificación , Pregabalina/farmacología , Administración Oral , Ecocardiografía/veterinaria , Masculino , Femenino , Presión Sanguínea/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Respiratoria/efectos de los fármacos , Analgésicos/administración & dosificación , Analgésicos/farmacología , Relación Dosis-Respuesta a Droga , Distribución AleatoriaRESUMEN
This study aimed to compare the effect of a bioceramic sealer (iRoot SP) and a resin-based sealer (AH Plus) on the outcome of root canal treatment in a 2-year follow-up. Seventy-six teeth with irreversibly or necrotic pulp were recruited. After instrumentation and disinfection, the root canals were obturated using warm vertical compaction with iRoot SP (n = 43) or AH Plus (n = 33). Patients were followed up by clinical and radiographic examination at 6 12 and 24 months with recall rates of 84.2%, 65.8% and 48.7%, respectively. During each recall session, the success rates were 80%, 85.2% and 85% in the iRoot SP group and 82.8%, 91.3% and 88.2% in the AH Plus group. The success rates of the two groups did not differ significantly (p > 0.05). The bioceramic sealer resulted in a similar clinical performance and success rate to the resin-based sealer in endodontic treatment during a 2-year follow-up.
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Cavidad Pulpar , Materiales de Obturación del Conducto Radicular , Humanos , Cavidad Pulpar/diagnóstico por imagen , Resinas Epoxi , Materiales de Obturación del Conducto Radicular/uso terapéutico , Tratamiento del Conducto Radicular , Resinas de Plantas , Obturación del Conducto Radicular/métodosRESUMEN
According to crystal engineering, the pharmaceutical intermediate m-nitrobenzoic acid (MNBA), which contains a carboxylic acid group, was selected as a coformer (CCF) for drug cocrystallization with famotidine (FMT), and a new stable FMT salt cocrystal was synthesized. The salt cocrystals were characterized by scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, infrared spectroscopy, powder X-ray diffraction and X-ray single crystal diffraction. A single crystal structure of FMT-MNBA (1:1) was successfully obtained, and then the solubility and permeability of the newly synthesized salt cocrystal were studied. The results showed that, compared with free FMT, the FMT from the FMT-MNBA cocrystal showed improved permeability. This study provides a synthetic method to improve the permeability of BCS III drugs, which will contribute to the development of low-permeability drugs.
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Objective: To probe into the clinical efficacy of tripterygium wilfordii glycoside (TWGs) tablets combined with acitretin capsules in the treatment of patients with moderate to severe plaque psoriasis (MSPP). Methods: Thirty-six patients with MSPP were collected and divided into three groups, namely, group A (n = 12, TWG tablets + acitretin capsules), group B (n = 12, compound glycyrrhizin capsules + acitretin capsules), and group C (n = 12, acitretin capsules). The general data of the patients was recorded. In addition, a comparison was made before treatment, 4 weeks and 8 weeks after treatment in terms of the clinical efficacy, liver function indicators (alanine aminotransferase (ALT), aspartate transaminase (AST), and creatinine), psoriasis area, and severity index (PASI) scores. The incidence of adverse reactions after treatment and the recurrence rate during two months of follow-up was statistically analyzed. Results: The therapeutic effect of group A was superior to the other two groups, with obviously more satisfactory results of serum parameters, clinical efficacy and PASI score, and incidence of adverse reactions. Conclusions: TWGs combined with acitretin had better therapeutic effects and higher safety in the treatment of MSPP.
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Many studies have reported that hydroxyl radical (HOË) driven advanced oxidation processes (AOPs) could degrade fluoroquinolones (FQs) antibiotics effectively. Compared with HOË, sulfate radical (SO4Ë-) shows a similar oxidation capacity but a longer half-life. SO4Ë- could cause chain reactions and resulted in the generation of halogen radicals and carbonate radicals from the main anions in sea water including Cl-, Br- and HCO3 -. However, few studies were focused on the degradation of FQs in marine aquaculture water and seawater, as well as the bioaccumulation of transformation products. As a typical member of FQs, flumequine (FLU) was degraded by UV/peroxodisulfate (PDS) AOPs in synthetic fresh water, marine aquaculture water and seawater. The reaction rate constants in the three water samples were 0.0348 min-1, 0.0179 min-1 and 0.0098 min-1, respectively. The reason was attributed to the inhibition of the anions as they could consume SO4Ë- and initiate the quenching reaction of free radicals. When the pH value increased from 5 to 9, the reaction rate decreased from 0.0197 min-1 to 0.0066 min-1. The energy difference between HOMO and LUMO of FLU was calculated to be 8.07 eV indicating that FLU was a stable compound. The atoms on quinolone ring of FLU with high negative charge would be more vulnerable to attack by free radicals through electrophilic reactions. Two possible degradation pathways of FLU were inferred according to the degradation products. Preliminary bioaccumulation analysis of transformation products by the EPI suite software proved that the values of log K ow and log BCF of the final product P100 were less than those of FLU and the intermediates.
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The establishment of water quality criteria (WQC) for copper (Cu) was used as the basis for an ecological risk assessment of marine Cu pollution in Liaodong Bay, China. Published ecotoxicity data for Cu were obtained and supplemented with the results of acute Cu toxicity tests. The marine WQC for Cu in Liaodong Bay was developed using a species sensitivity distribution method with a safety factor of 2.0 and the USEPA acute-to-chronic ratio method. The ecological risk of Cu in Liaodong Bay was assessed by comparing the seawater Cu concentrations with the developed WQC. The results of this study showed that the acute and chronic Cu concentrations in Liaodong Bay were 3.31 and 2.18⯵g/L, respectively. Comparison of the WQC to Cu concentrations in the bay resulted in risk quotients slightly >1.0 and typically ≤2.0. These data suggest that certain organisms in Liaodong Bay are at risk. These results can assist in the development of a pollution control management approach for the bay.
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Contaminantes Químicos del Agua , Calidad del Agua , Cobre/toxicidad , Cobre/análisis , Bahías , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis , Medición de Riesgo , China , Monitoreo del AmbienteRESUMEN
INTRODUCTION: Atopic dermatitis (AD) is a common chronic recurrent inflammatory skin disease. The pathogenesis is unclear but may be related to genetic, immune, and environmental factors and abnormal skin barrier function. Symbiotic microorganisms in the gut and on the skin are associated with AD occurrence. AREAS COVERED: We discuss the metabolism and distribution of intestinal and skin flora and review their relationship with AD, summarizing the recent applications of intestinal and skin flora in AD treatment, and discussing the prospect of research on these two human microbiota systems and their influence on AD treatment. The PubMed database was searched to identify relevant publications from 1949 to 2020 for the bibliometric analysis of atopic dermatitis and symbiotic microorganisms. EXPERT OPINION: Many studies have suggested a potential contribution of microbes in the intestine and on the skin to AD. Bacteria living on the skin can aggravate AD by secreting numerous virulence factors. Moreover, the metabolism of intestinal flora can influence AD occurrence and development via the circulatory system. Current evidence suggests that by regulating intestinal and skin flora, AD can be treated and prevented.
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Dermatitis Atópica , Microbioma Gastrointestinal , Microbiota , Dermatitis Atópica/terapia , Humanos , Piel/patologíaRESUMEN
Brominated disinfection byproducts (Br-DBPs) are formed during the disinfection process of water containing bromine ions, such as marine aquaculture water. Little attention has been paid to Br-DBPs with anthropogenic chemicals as precursors. This study summarized the sodium hypochlorite (NaClO) oxidation of three frequently used pharmaceuticals, including two antibiotics, norfloxacin (NOR) and sulfamethoxazole (SMX), and the growth hormone estrogen 17ß-estradiol (E2). Transformations of the pharmaceuticals were found to be faster in marine aquaculture water than in distilled water. Several Br-DBPs and Cl-DBPs were identified for NOR, SMX, and E2. It was shown that the carboxyl group, piperazine ring, C3, and C8 atoms were the primary reaction sites on NOR. The aniline moiety and S-N bond were identified to be the reaction sites on SMX. The C2, C4, C9, and C16 atoms were the potential reaction centers on E2. Preliminary calculation by QSAR model indicated that the value of logKow significantly increased with an increase in the number of bromine atoms in the Br-DBPs. The results of the bioconcentration factors (BCF) analysis suggested that the bioaccumulation of Br-DBPs were greater than that chlorinated DBPs (Cl-DBPs) in distilled water.
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Desinfectantes , Contaminantes Químicos del Agua , Purificación del Agua , Bromuros , Desinfección , Estradiol , Halogenación , Norfloxacino , Sulfametoxazol , Contaminantes Químicos del Agua/análisisRESUMEN
We report the dielectric properties of pure water confined in a silica hydrophilic nanopore determined from the computation of the density of liquid in the confined phase by the grand canonical Monte Carlo (GCMC) simulations. The silica cylindrical nanopore is divided into n concentric radial shells to get a better insight into the dielectric properties of nanoconfined water. We find that the average values of the dielectric constants are very close and almost independent of the number of concentric radial shells. The decrease in the dielectric constant of confined pure water is due to the strong orientation of water dipoles in the vicinity of the surface while water dipoles do not exhibit any preferential orientation in bulk phase.
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The ultraviolet/peroxydisulfate (UV/PDS) system was used to degrade ofloxacin (OFL) in fresh water, synthetic marine aquaculture water and synthetic seawater. The comparison of the reaction degradation rate constants proved that the order of reaction rate was the following: synthetic seawater (0.77 min-1) > synthetic marine aquaculture water (0.74 min-1) > freshwater (0.30 min-1). Bromide (Br-) and bicarbonate (HCO3-) promote the degradation of OFL, whereas chloride (Cl-) inhibits the degradation. The piperazine ring of OFL was the main reactive group, and atoms N1, C6, C7 and N2 were identified as the reaction sites. Based on the intermediate and final products, the possible degradation pathways of OFL in the three kinds of water were proposed. Additionally, during the UV/PDS treatment of synthetic marine aquaculture water containing Cl- and Br-, the oxidation products of OFL showed a slight toxicity to Chlorella pyrenoidosa (C. pyrenoidosa) and Priacanthus tayenus (P. tayenus). The maximum growth inhibition rate of the products to C. pyrenoidosa was 9.72%. The products also caused liver cells of P. tayenus to be damaged and reduced the species richness and diversity of intestinal microorganism. Nevertheless, compared with the products degraded by traditional disinfection methods using NaClO, the biological toxicities were much lower. UV/PDS can be used for seawater as a new alternative disinfection method.
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Agua de Mar/química , Chlorella , Cinética , Ofloxacino , Oxidación-Reducción , Rayos Ultravioleta , Contaminantes Químicos del Agua , Purificación del AguaRESUMEN
Melanoma is a malignant skin tumor that results in poor disease prognosis due to unsuccessful treatment options. During the early stages of tumor progression, surgery is the primary approach that assures a good outcome. However, in the presence of metastasis, melanoma hasbecome almost immedicable, since the tumors can not be removed and the disease recurs easily in a short period of time. However, in recent years, the combination of nanomedicine and chemotherapeutic drugs has offered promising solutions to the treatment of late-stage melanoma. Extensive studies have demonstrated that nanomaterials and their advanced applications can improve the efficacy of traditional chemotherapeutic drugs in order to overcome the disadvantages, such as drug resistance, low drug delivery rate and reduced targeting to the tumor tissue. In the present review, we summarized the latest progress in imaging diagnosis and treatment of melanoma using functional nanomaterials, including polymers, liposomes, metal nanoparticles, magnetic nanoparticles and carbon-based nanoparticles. These nanoparticles are reported widely in melanoma chemotherapy, gene therapy, immunotherapy, photodynamic therapy, and hyperthermia.
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Melanoma/diagnóstico por imagen , Melanoma/terapia , Nanomedicina , Nanoestructuras/química , Antineoplásicos/uso terapéutico , Sistemas de Liberación de Medicamentos , Fiebre , Terapia Genética , Humanos , Inmunoterapia , FotoquimioterapiaRESUMEN
The antibacterial agent norfloxacin (NOR) and sodium hypochlorite (NaClO), which are both widely used in marine culture, react with each other to form the halogenated disinfection byproducts (X-DBPs). The effects of the water characteristics and iodide concentration on the reaction kinetics were investigated. The results showed that the reaction rate of NOR with NaClO increases from 0.0586 min-1 to 0.1075 min-1 when the iodide concentration was changed from 0⯵g-1 to 50⯵g-1. This demonstrated the enhancement of NOR oxidation in the presence of iodide ions. Four novel iodinated DBPs (I-DBPs) were identified in the marine culture water. Iodine substitutions occurred at the C3 and C8 positions of NOR. The formation mechanisms of X-DBPs in the marine culture water were proposed based on the intermediate and final products. NOR may undergo a ring-opening reaction, a de-carbonyl reaction and substitution to form intermediates and finally generate the X-DBPs. Furthermore, the predicted logKOW and logBCF values of the I-DBPs were higher than that of the Br-DBPs and Cl-DBPs. The AOX concentration in the synthetic water samples decreased in the following order: seawater (8.49â¯mgâ¯L-1)â¯>â¯marine culture water (4.05â¯mgâ¯L-1)â¯>â¯fresh water (1.89â¯mgâ¯L-1). The amount of AOX also increased with the increase in iodide concentration. These results indicated that the I-DBPs were more toxic than their brominated and chlorinated analogues.
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Organismos Acuáticos/efectos de los fármacos , Desinfectantes/química , Desinfección/métodos , Yoduros/química , Norfloxacino/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Halogenación , Cinética , Oxidación-ReducciónRESUMEN
Although the antimicrobial properties of kojic acid have been recognized, the subcellular mechanism of bacterial inactivation caused by it has never been clearly elucidated. In the present study, the antibacterial and anti-biofilm activity of kojic acid was evaluated against five foodborne pathogens including Listeria monocytogenes, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Salmonella typhimurium. The antibacterial activity was determined by minimum inhibitory concentration, minimum bactericidal concentration, and the time-kill assay. Among them, the susceptibility of Escherichia coli was significant with the lowest minimum inhibitory concentration and minimum bactericidal concentration values of 10 and 20 mM, respectively. Subcellular mechanism of bacterial inactivation related to kojic acid was revealed through comprehensive factors including cell morphology, membrane permeability, K+ leakage, zeta potential, intracellular enzyme, and DNA assay. Results demonstrated that bacterial inactivation caused by kojic acid, especially for Gram-negative bacteria, was primarily induced by the pronounced damage to the cell membrane integrity. Leakage of intracellular enzyme to the supernatants implied that the cell membrane permeability was compromised. Consequently, the release of K+ from the cytosol leads to the alterations of the zeta potential of cells, which would disturb the subcellular localization of some proteins and thereby cause the bacterial inactivation. The free -CH2OH group at the C-2 of kojic acid could play more significant role in the antimicrobial performance of kojic acid against Gram-negative bacteria. Moreover, remarkable interaction with DNA was also observed. Kojic acid at sub-minimum inhibitory concentration inhibited biofilm formation by these bacteria.
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Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Microbiología de Alimentos , Pironas/farmacología , Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/genética , ADN Bacteriano/aislamiento & purificación , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Contaminación de Alimentos/prevención & control , Genoma Bacteriano , Listeria monocytogenes/efectos de los fármacos , Listeria monocytogenes/genética , Pruebas de Sensibilidad Microbiana , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/genéticaRESUMEN
This work aims to prepare ferulic acid alkyl esters (FAEs) through the lipase-catalyzed reaction between methyl ferulate and various fatty alcohols in deep eutectic solvents and ascertain their antibacterial activities and mechanisms. Screens of antibacterial effects of FAEs against Escherichia coli ATCC 25922 ( E. coli) and Listeria monocytogenes ATCC 19115 ( L. monocytogenes) revealed that hexyl ferulate (FAC6) exerted excellent bacteriostatic and bactericidal effects on E. coli and L. monocytogenes (minimum inhibitory concentration (MIC): 1.6 and 0.1 mM, minimum bactericidal concentration (MBC): 25.6 and 0.2 mM, respectively). The antibacterial mechanism of FAC6 against E. coli was systematically studied to facilitate its practical use as a food additive with multifunctionalities. The growth and time-kill curves implied the partial cell lysis and inhibition of the growth of E. coli caused by FAC6. The result related to propidium iodide uptake and cell constituents' leakage (K+, proteins, nucleotides, and ß-galactosidase) implied that bacterial cytomembranes were substantially compromised by FAC6. Variations on morphology and cardiolipin microdomains and membrane hyperpolarization of cells visually verified that FAC6 induced cell elongation and destructed the cell membrane with cell wall perforation. SDS-PAGE analysis and alterations of fluorescence spectra of bacterial membrane proteins manifested that FAC6 caused significant changes in constitutions and conformation of membrane proteins. Furthermore, it also could bind to minor grooves of E. coli DNA to form complexes. Meanwhile, FAC6 exhibited antibiofilm formation activity. These findings indicated that that FAC6 has promising potential to be developed as a multifunctional food additive.
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Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Aditivos Alimentarios/farmacología , Antibacterianos/química , Biopelículas/efectos de los fármacos , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacología , Escherichia coli/crecimiento & desarrollo , Escherichia coli/fisiología , Ésteres/química , Ésteres/farmacología , Aditivos Alimentarios/química , Listeria monocytogenes/efectos de los fármacos , Listeria monocytogenes/crecimiento & desarrollo , Pruebas de Sensibilidad MicrobianaRESUMEN
BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with poor survival rates. The presence of cancer stem-like cells (CSCs) is believed to be among the underlying reasons for the aggressiveness of PDAC, which contributes to chemoresistance and recurrence. However, the mechanisms that induce chemoresistance and inhibit apoptosis remain largely unknown. METHODS: We used serum-free medium to enrich CSCs from panc-1 human pancreatic cancer cells and performed sphere formation testing, flow cytometry, quantitative reverse transcription polymerase chain reaction (RT-qPCR) and semi-quantitative western blotting to confirm the stemness of panc-1 CSCs. Hallmarks of endoplasmic reticulum (ER) stress, including IRE1, PERK, ATF4, ATF6α, GRP78 and uPA expression, were detected after gemcitabine treatment. Effects of gemcitabine-induced uPA expression on cell invasion, sphere formation, colony formation and gemcitabine sensitivity were detected. Electrophoretic mobility shift assays (EMSAs) and RNA-immunoprecipitation (RIP) were performed to detect interaction between the uPA mRNA 3'-UTR and mutant p53-R273H expressed by panc-1 CSCs. The effects of upregulated uPA by gemcitabine on apoptosis were detected by Annexin V-FITC/PI staining, and the impact of uPA on small molecule CP-31398-restored mutant p53 transcriptional activity was measured by a luciferase reporter assay. RESULTS: Enriched panc-1 CSCs expressing high levels of CD44 and CD133 also produced significantly higher amounts of Oct4 and Nanog. Compared with panc-1 cells, panc-1 CSCs presented chemoresistance to gemcitabine. ER stress gene detections demonstrated effects of gemcitabine-induced ER stress on both the pro-apoptotic and pro-survival branches. ER stress-induced ATF6α upregulated level of uPA by transcriptionally activating GRP78. Gemcitabine-induced uPA promoted invasion, sphere formation and colony formation and attenuated apoptosis induced by gemcitabine in panc-1 CSCs, depending on interaction with mutant p53-R273H. Upregulation of uPA abolished CP-31398-mediated restoration of mutant p53 transcriptional activity in panc-1 CSCs. CONCLUSION: Gemcitabine treatment induced ER stress and promoted mutant p53-R273H stabilization via transcriptionally activated uPA which may contribute to chemoresistance to gemcitabine. Notably, upregulation of uPA by gemcitabine treatment may lead to the failure of CP-31398; thus, a novel strategy for modulating mutant p53 function needs to be developed.
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Antimetabolitos Antineoplásicos/farmacología , Desoxicitidina/análogos & derivados , Estrés del Retículo Endoplásmico/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Células Madre Neoplásicas/efectos de los fármacos , Neoplasias Pancreáticas/tratamiento farmacológico , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Desoxicitidina/farmacología , Chaperón BiP del Retículo Endoplásmico , Proteínas de Choque Térmico/metabolismo , Humanos , Mitocondrias/metabolismo , Mitocondrias/patología , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Páncreas/efectos de los fármacos , Páncreas/metabolismo , Páncreas/patología , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Pirimidinas/farmacología , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/genética , GemcitabinaRESUMEN
BACKGROUND: To date, literature has emerged that shows contradictory results about the prognostic role of microvessel density (MVD) in esophageal squamous cell cancer (ESCC). The aim of the study set out to evaluate the correlation between MVD and the prognosis of ESCC. METHODS: Identified publications from various databases were obtained and reviewed. A meta-analysis was performed to evaluate the prognostic role of MVD among ESCC patients. RESULTS: A total of 11 eligible studies containing 891 ESCC cases were included in the meta-analysis. The pooled hazard ratio for overall survival was 2.39 (95% confidence interval 1.92-2.96, Pâ<â.001). Heterogeneity among the studies was not significant, and publication bias was not found. Subgroup analyses were also performed on different issues, such as districts, antibodies, and median age. CONCLUSION: High MVD is a prognostic factor among ESCC that indicated worse prognosis in these patients. More studies are needed, and through abundant evidence, the topic could be re-evaluated by then.