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This work deals with data-driven control for non-minimum phase (NMP) systems, where the goal is to design a controller for a plant whose model is unknown by using a batch of input-output data collected from it. The approach is based on the Model Reference paradigm, where a transfer function matrix - the reference model - is used to specify the desired closed-loop performance. The NMP systems issue in Model Reference approaches is a well-known problem in control literature and it is no different in data-driven methods. This work explains how to adapt the formulation of the Optimal Controller Identification (OCI) method to cope with this class of systems. Considering a convenient parametrization of the reference model and a flexible performance criterion, it is possible to identify the NMP transmission zeros of the plant along with the optimal controller parameters, as it will be shown. Both diagonal and block-triangular reference model structures are treated in detail. Simulation examples show the effectiveness of the proposed approach.
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OBJECTIVES: This study aimed to evaluate the optical and mechanical performance of two single-shade resin-based composites (RBCs) compared to those of a conventional RBC for restoring posterior teeth. METHODS: Two single-shade RBCs, Omnichroma (Tukoyama) and Vittra Unique APS (FGM), and a conventional RBC, Filtek Z350XT shade A2 (3M Oral Care), were evaluated in this study. The optical shade-matching performance was measured using a spectrophotometer. The light emitted by VALO Grand (Ultradent) and transmitted through the 2.0-mm RBC specimens was evaluated using beam profiling. Knoop hardness (KH, N/mm2), degree of conversion (DC, %) at the top and bottom, flexural strength (FS, MPa), elastic modulus (E, GPa), postgel shrinkage (Shr, %), and shrinkage stress (MPa) were evaluated. Scanning electron microscopy (SEM) was used to characterize the filler. Data for FS, E, and Shr were analyzed by one-way analysis of variance (ANOVA) and KH and DC by repeated one-way ANOVA measurement followed by Tukey test (α=0.05). The modified von Mises stress values, light transmission, and SEM images were analyzed qualitatively. RESULTS: All single-shade RBCs exhibited higher chromatic adaptation than the Filtek Z350XT (p<0.001). Omnichroma exhibited less color difference than Vittra Unique APS, irrespective of the shade. The light transmitted through Omnichroma and Vittra Unique APS increased during polymerization. KH and DC values were significantly reduced from the top to the bottom of the specimens for all RBCs (p<0.001); however, the ratio values were always higher than 80%. In general, all RBCs demonstrated similar mechanical properties. All RBCs exhibited a similar FS (p=0.083) and Shr value (p=0.144). Filtek Z350XT exhibited significantly higher E (p<0.001) than both single-shade RBCs. All RBCs exhibited similar shrinkage stress during restoration and similar residual stress during occlusal loading. CONCLUSIONS: Single-shade Omnichroma and Vittra Unique APS increased light transmission during light-activation, demonstrating better chromatic adaptation than conventional Filtek Z350XT. In general, Omnichroma and Vittra Unique APS exhibited similar mechanical properties and shrinkage stress distributions as Filtek Z350XT during light-activation and occlusal loading.
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Resinas Compuestas , Materiales Dentales , Estrés Mecánico , Resinas Compuestas/uso terapéutico , Módulo de Elasticidad , Dureza , Ensayo de Materiales , PolimerizacionRESUMEN
OBJECTIVES: To evaluate the volume and depth of enamel loss promoted by 37.5% and 7.5% hydrogen peroxide (HP) gels, and quantify the loss of calcium (Ca) and phosphate (P) ions by using ion chromatography (IC) analysis after bleaching. METHODS: Sixty bovine enamel specimens were randomly divided into three groups: Control - no bleaching gel; HP37.5%, application of HP 37.5% for 45 minutes for 14 days; and HP7.5%, application of HP 7.5% for 3 applications of 8 minutes. The surface analysis (n=5) was performed using a scanning electron microscope (SEM) and dispersive energy system (EDS) to calcium and phosphorus dosage. The micro-CT was used for the enamel loss analysis (n=5). IC was used to analyze extracted Ca and P (n=10). Data were analyzed by one-way ANOVA and two-way repeated measures ANOVA, followed by Tukey and Dunnett's tests (α=0.05). RESULTS: Significantly higher volume and depth of enamel loss were found for bleached groups compared with the control group. HP7.5% had significantly higher enamel change than HP37.5%. SEM showed higher enamel porosity for HP37.5% and HP7.5% compared to control. The IC demonstrated a significant increase of Ca incorporated into the gel, however, only HP7.5% had a higher P presence than the control group. The HP7.5% showed higher Ca and P ion exchange than HP37.5% (p<0.001). CONCLUSION: HP37.5% and HP7.5%, caused enamel mineral changes compared with the control group. The IC method was demonstrated to be an effective methodology for detecting enamel mineral loss by the bleaching gel.
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Blanqueadores Dentales , Blanqueamiento de Dientes , Animales , Bovinos , Calcio , Blanqueamiento de Dientes/métodos , Esmalte Dental , Microtomografía por Rayos X , Peróxido de Hidrógeno/química , Minerales , Fosfatos , GelesRESUMEN
The occurrence of antimicrobial resistance in microorganisms isolated from eggshells, especially Enterococcus, might serve as a parameter to assess the selection of bacteria due to the use of drugs in the diet of laying hens. In order to evaluate the frequency and the antimicrobial resistance profile of Enterococcus spp. isolated from the eggshells, 225 Hy-line laying hens were submitted to a 25-d long trial. The treatments were the following: hens fed ration without antimicrobials (control) and groups that received oxytetracycline (10 mg kg-1), doxycycline (20 mg kg-1), lincomycin (50 mg kg-1), and enrofloxacin (10 mg kg-1) in the ration for 5 d. Six replications were analyzed per treatment, composed of a pool of 5 eggs each. They were collected before treatment and on days 3, 6, 15, and 25, totaling 150 samples. Eggshells were submitted to counts of Enterococcus spp., which were identified by proteomic analyses. Antimicrobial resistance was determined by the disk-diffusion test. It was observed that 97.3% (n = 146) of the samples were contaminated with Enterococcus spp. There were no differences (P > 0.05) in the bacterial counts between treatments on the same day of evaluation. E. faecalis and E. faecium were the most frequent on the eggshells of all treatments. Multiresistance to the four classes of antimicrobials was also verified in the isolated bacteria. A total of 83% of the Enterococcus isolates showed resistance to neomycin, which was not administered to the hens, demonstrating an environmental problem. Thus, feeding laying hens with diets added with antimicrobials induces drug resistance in Enterococcus spp., isolated form the eggshells.
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Antiinfecciosos , Enterococcus , Animales , Antibacterianos/farmacología , Pollos , Farmacorresistencia Bacteriana , Cáscara de Huevo , Femenino , Óvulo , ProteómicaRESUMEN
Ocular toxoplasmosis is the major cause of infectious posterior uveitis worldwide, inducing visual field defect and/or blindness. Despite the severity of this disease, an effective treatment is still lacking. In this study, spiramycin-loaded PLGA implants were developed aiming at the treatment of ocular toxoplasmosis. Implants were manufactured by a hot-molding technique, characterized by Fourier Transform Infrared Spectroscopy, X-Ray Diffraction, Differential Scanning Calorimetry, Scanning Electron Microscopy; evaluated in terms of ocular biocompatibility by immunofluorescence, flow cytometry, cell migration, Hen's egg test-chorioallantoic membrane (HET-CAM) irritation test; and investigated in terms of in vitro efficacy against Toxoplasma gondii . Characterization techniques indicated that spiramycin was dispersed into the polymeric chains and both substances preserved their physical structures in implants. The HET-CAM test indicated that implants did not induce hemorrhage or coagulation, being non-irritant to the CAM. ARPE-19 cells showed viability by MTT assay, and normality in cell cycle kinetics and morphology, without stimulating cell death by apoptosis. Finally, they were highly effective against intracellular parasites without inducing human retinal pigment epithelial cell death. In conclusion, spiramycin-loaded PLGA implants represent a promising therapeutic alternative for the local treatment of ocular toxoplasmosis.
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Sistemas de Liberación de Medicamentos/métodos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Espiramicina/administración & dosificación , Toxoplasmosis Ocular/tratamiento farmacológico , Animales , Técnicas de Cultivo de Célula , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Pollos , Membrana Corioalantoides , Células Epiteliales , Humanos , Microscopía Electrónica de Rastreo , Epitelio Pigmentado de la Retina , Espiramicina/uso terapéutico , Toxoplasma/efectos de los fármacosRESUMEN
AIM: To analyse the cytotoxicity, colour change and radiopacity of MTA Flow (MTA), UltraCal XS (UC) and Bio-C Temp (BT). METHODOLOGY: Human dental pulp cells (hDPCs) stimulated with lipopolysaccharide (LPS) were placed in contact with several dilutions of culture media previously exposed to the experimental materials and tested for cell viability using MTT. Bovine teeth were prepared to simulate an open apex and to mimic extensive crown fracture. The roots were filled with a mixture of agar and blood, and the materials placed over this mixture. The control group consisted of teeth filled only with agar and blood. Colour assessment analyses were performed before and immediately after material insertion and repeated at 30, 45 and 60 days using a spectrophotometer. The total colour change (ΔEab , ΔE00 and whiteness index (WI)) was calculated based on the CIELAB colour space. Digital radiographs were acquired for radiopacity analysis. Cell viability was analysed by one-way anova, whilst differences in colour parameters (ΔEab , ΔE00 and WI) were assessed by two-way repeated measures anova (α = 0.05). Tukey's test was used to compare the experimental groups, and Dunnett's test was used to compare the experimental groups with the control group. RESULTS: MTA, UC and BT had similar cell viability to that of the control group (DMEM) (P > 0.05), except for the BT group at the 1 : 1 and 1 : 2 dilutions, which had significantly lower viability (P < 0.001). All materials were associated with discoloration values greater than what is considered to be the acceptable threshold, and BT resulted in less or similar tooth colour change than MTA and UC, respectively. Decreasing radiopacity over time was observed only in the MTA group (P = 0.007). Lower values of radiopacity were found in the BT group compared with the UC and MTA groups (P < 0.001). CONCLUSIONS: The new bioceramic material (BT) had acceptable cell viability, similar to that of MTA and UC at the highest dilutions, and BT resulted in less tooth colour change than MTA and UC. Despite its lower radiopacity, BT was identified radiographically.
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Materiales de Obturación del Conducto Radicular , Decoloración de Dientes , Compuestos de Aluminio , Animales , Compuestos de Calcio , Bovinos , Supervivencia Celular , Combinación de Medicamentos , Humanos , Óxidos , Endodoncia Regenerativa , SilicatosRESUMEN
Rheumatoid arthritis is an autoimmune pathology that manifests as chronic inflammatory arthropathy and synovitis. Treatment of rheumatoid arthritis is based on the administration of different types of drugs, including leflunomide, an antirheumatic drug. However, the long-term systemic use of leflunomide may be associated with adverse effects. Local therapy could be an efficient strategy to treat synovitis triggered by rheumatoid arthritis without inducing adverse effects. In this study, leflunomide-loaded poly(ε-caprolactone) implants (leflunomide PCL implants) were evaluated as local drug delivery systems capable of attenuating inflammation and angiogenesis, which represent events of synovitis. Leflunomide PCL implants were designed by hot molding technique; and they were characterized by FTIR and DSC. These analytical techniques demonstrated the chemical integrity and dispersion of drug into the polymeric chains. Then, a spectrophometric method was developed and validated to quantify the leflunomide incorporated into the PCL implants and released from them. Linearity was obtained by ordinary least squares regression method to estimate the linear regression equation. Residues were evaluated considering normality, independence and homoscedasticity. Precision was lower than 5 %, and accuracy ranged from 98 to 104.5 %. Quantitation limit was 2.0 µg mL-1. PCL implants provided controlled and sustained release of leflunomide for 30 consecutive days after inserting these systems in the subcutaneous tissue of mice. The main mechanisms of drug delivery were solubilization and diffusion from polymer. Then, a non-biocompatible sponge was inserted into the subcutaneous tissue of mice to function as a frame to develop the inflammatory and angiogenic processes. Leflunomide PCL implants were inserted in direct contact with the sponge. At 4, 7 and 10 days after-sponge implantation, the key components of inflammatory angiogenesis were measured to verify the regression of these events induced by drug. Leflunomide controlled released from polymeric implants downregulated the neutrophil and monocyte/macrophage infiltration due to the reduced expression of myeloperoxidase (MPO) and N-acetyl-ß-d-glucosaminidase (NAG), respectively. As the influx of these pro-inflammatory cells was modulated by leflunomide, the production of nitric oxide (NO), a pro-inflammatory substance, reached low concentrations in the sponge. As a consequence of the modulation of inflammation at the pathological site, the angiogenic process was downregulated, since the hemoglobin levels in the sponge were drastically reduced. The accumulation of leflunomide in the pathological site did not induce nephrotoxicity or hepatototoxicity, as confirmed by histological analyses. Finally, intra-articular leflunomide PCL implants represent a potential therapeutic alternative to treat locally the synovitis triggered by rheumatoid arthritis without inducing systemic adverse effects.
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Antirreumáticos/administración & dosificación , Artritis Reumatoide/tratamiento farmacológico , Leflunamida/administración & dosificación , Sinovitis/tratamiento farmacológico , Animales , Antirreumáticos/farmacología , Antirreumáticos/toxicidad , Rastreo Diferencial de Calorimetría , Modelos Animales de Enfermedad , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Implantes de Medicamentos , Femenino , Inflamación/tratamiento farmacológico , Inflamación/patología , Leflunamida/farmacología , Modelos Lineales , Ratones , Neovascularización Patológica/tratamiento farmacológico , Neovascularización Patológica/patología , Óxido Nítrico/metabolismo , Poliésteres/química , Espectrofotometría/métodos , Espectroscopía Infrarroja por Transformada de Fourier , Sinovitis/patologíaRESUMEN
OBJECTIVES: To evaluate the effect of light curing bulk fill resin composite restorations on the increase in the temperature of the pulp chamber both with and without a simulated pulpal fluid flow. METHODS AND MATERIALS: Forty extracted human molars received a flat occlusal cavity, leaving approximately 2 mm of dentin over the pulp. The teeth were restored using a self-etch adhesive system (Clearfil SE Bond, Kuraray) and two different bulk fill resin composites: a flowable (SDR, Dentsply) and a regular paste (AURA, SDI) bulk fill. The adhesive was light cured for 20 seconds, SDR was light cured for 20 seconds, and AURA was light cured for 40 seconds using the Bluephase G2 (Ivoclar Vivadent) or the VALO Cordless (Ultradent) in the standard output power mode. The degree of conversion (DC) at the top and bottom of the bulk fill resin composite was assessed using Fourier-Transform Infra Red spectroscopy. The temperature in the pulp chamber when light curing the adhesive system and resin composite was measured using a J-type thermocouple both with and without the presence of a simulated microcirculation of 1.0-1.4 mL/min. Data were analyzed using Student t-tests and two-way and three-way analyses of variance (α=0.05 significance level). RESULTS: The irradiance delivered by the light-curing units (LCUs) was greatest close to the top sensor of the MARC resin calibrator (BlueLight Analytics) and lowest after passing through the 4.0 mm of resin composite plus 2.0 mm of dentin. In general, the Bluephase G2 delivered a higher irradiance than did the VALO Cordless. The resin composite, LCU, and region all influenced the degree of cure. The simulated pulpal microcirculation significantly reduced the temperature increase. The greatest temperature rise occurred when the adhesive system was light cured. The Bluephase G2 produced a rise of 6°C, and the VALO Cordless produced a lower temperature change (4°C) when light curing the adhesive system for 20 seconds without pulpal microcirculation. Light curing SDR produced the greatest exothermic reaction. CONCLUSIONS: Using simulated pulpal microcirculation resulted in lower temperature increases. The flowable composite (SDR) allowed more light transmission and had a higher degree of conversion than did the regular paste (AURA). The greatest temperature rise occurred when light curing the adhesive system alone.
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Resinas Compuestas , Luces de Curación Dental , Dentina , Humanos , Ensayo de Materiales , Microcirculación , TemperaturaRESUMEN
BACKGROUND: Class 3 semaphorins are soluble proteins involved in cell adhesion and migration. Semaphorin-3A (Sema3A) was initially shown to be involved in neuronal guidance, and it has also been reported to be associated with immune disorders. Both Sema3A and its receptors are expressed by most immune cells, including monocytes, macrophages, and lymphocytes, and these proteins regulate cell function. Here, we studied the correlation between Sema3A-induced changes in biophysical parameters of thymocytes, and the subsequent repercussions on cell function. METHODS: Thymocytes from mice were treated in vitro with Sema3A for 30min. Scanning electron microscopy was performed to assess cell morphology. Atomic force microscopy was performed to further evaluate cell morphology, membrane roughness, and elasticity. Flow cytometry and/or fluorescence microscopy were performed to assess the F-actin cytoskeleton and ROCK2. Cell adhesion to a bovine serum albumin substrate and transwell migration assays were used to assess cell migration. RESULTS: Sema3A induced filopodia formation in thymocytes, increased membrane stiffness and roughness, and caused a cortical distribution of the cytoskeleton without changes in F-actin levels. Sema3A-treated thymocytes showed reduced substrate adhesion and migratory ability, without changes in cell viability. In addition, Sema3A was able to down-regulate ROCK2. CONCLUSIONS: Sema3A promotes cytoskeletal rearrangement, leading to membrane modifications, including increased stiffness and roughness. This effect in turn affects the adhesion and migration of thymocytes, possibly due to a reduction in ROCK2 expression. GENERAL SIGNIFICANCE: Sema3A treatment impairs thymocyte migration due to biomechanical alterations in cell membranes.
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Fenómenos Biomecánicos/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Semaforina-3A/farmacología , Timocitos/efectos de los fármacos , Citoesqueleto de Actina/efectos de los fármacos , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Animales , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Membrana Celular/ultraestructura , Células Cultivadas , Ratones Endogámicos C57BL , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Seudópodos/efectos de los fármacos , Seudópodos/metabolismo , Seudópodos/ultraestructura , Timocitos/metabolismo , Timocitos/ultraestructura , Quinasas Asociadas a rho/metabolismoRESUMEN
In order to evaluate the microbiological quality of broiler chickens produced in Minas Gerais State, 240 samples of broiler carcasses from the five regions of the Minas Gerais State were collected, by official inspection services, for one year. The samples were submitted to counts of total and thermotolerant coliforms, coagulase-positive and negative Staphylococcus, besides Campylobacter spp., Listeria monocytogenes, E.coli O157:H7, and Salmonella spp. resource. The results showed the presence of total and thermotolerant coliforms in 34.2% and 13.5% of broiler carcasses evaluated, respectively. All tested samples were positive for Staphylococcus spp., 9.1% for Salmonella spp., 15.5% for Listeria monocytogenes, and 2.1% for Campylobacter spp. E.coli O157:H7 was not isolated from the samples.(AU)
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Animales , Carne/clasificación , Carne/microbiología , Campylobacter , Listeria monocytogenes , Aves de Corral , StaphylococcusRESUMEN
Introduction: Obstetric haemorrhage is the leading cause of maternal mortality worldwide and in most cases it relates to uterine atony. Even though an oxytocin bolus is used routinely, additional infusion of oxytocin may be required if haemorrhage occurs. Objectives: To compare the effects of 20 IU oxytocin infusion and 5 IU bolus with 5 IU bolus and 500ml normal saline on the control of blood loss in antepartum lower segment caesarean section. Methods: A double-blind randomized controlled trial was conducted in the Teaching Hospital, Peradeniya, Sri Lanka. Ninety two pregnant women, forty six from each group were randomized to receive either intravenous slow 5 IU oxytocin bolus over 1 minute and additional 20 IU oxytocin infusion in 500 ml of 0.9% saline solution over 4 hours (Group-A) or 5 IU oxytocin bolus over 1 minute and 500 ml of 0.9% Saline over 4 hours (Group B). Visual assessment of mean blood loss was done by the surgeon and anaesthetist. Blood loss was calculated based on the body weight and haematocrit before and 48 hours after delivery. Results: Calculated mean blood loss (456.0ml vs 569.8ml) was significantly less in group A (p=0.046). Visual estimation of blood loss by surgeon (476.9 vs 552.1) (p=0.01) and anaesthetist (492.7 vs 557.2) (p= 0.03) were also significantly less in group A. Conclusions: Additional oxytocin infusion at antepartum caesarean section reduces blood loss during and after caesarean section significantly.
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The aim of this study was to access the genetic diversity and relatedness between Canindé and British Alpine goat breeds in the States of Piauí and Ceará using microsatellite markers. Genomic DNA was isolated from hair samples of 99 goats belonging to six different flocks. A panel of polymorphic heterologous microsatellite loci was used to genotype individuals. The microsatellite markers resulted in a total number of 145 alleles, with an average of 8.5 alleles per locus. The observed and expected heterozygosities were ≥0.687 and ≥0.627, respectively, for all loci. The polymorphic information content showed that all loci were highly informative with an overall mean of 0.757. Overall FST across all populations and loci was 18%, which was consistent with the coefficient of gene differentiation (GST = 0.104). AMOVA revealed that 12.8% of the variation was captured between breeds. The Bayesian STRUCTURE clustering detected the maximum likelihood for a model of two genetically distinct groups, in agreement with the number of predefined studied breeds and the two-dimensional plot from the PCoA analysis. The exotic British Alpine breed and the naturalized Brazilian Canindé breed were clearly differentiated by the microsatellite markers, indicating that these two breeds have distant genetic identities, despite the phenotypic similarity.
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Cabras/genética , Repeticiones de Microsatélite , Alelos , Animales , Brasil , Cruzamiento , Mapeo Cromosómico , ADN/genética , Flujo Genético , Variación Genética , Genética de Población , Genotipo , HeterocigotoRESUMEN
Drug delivery systems could be applied to locally treat cervical cancer, thus preventing the drawbacks of conventional therapy. In this study, anti-proliferative and anti-angiogenic effects of digoxin incorporated into poly(ε-caprolactone) implants were evaluated, aiming at the local treatment of cervical cancer. Implants were characterized, and the in vitro release profile of digoxin was demonstrated. Anti-proliferative and anti-angiogenic activities of digoxin were investigated by using chorioallantoic membrane and human cervix carcinoma (HeLa) cells, respectively. The chemical structure of digoxin and the semi-crystalline nature of poly(ε-caprolactone) were preserved after designing implants. The hydrophobicity of drug and polymer as well as the semi-crystalline structure provided a controlled diffusion of digoxin from implants. Digoxin released from implantable devices exhibited anti-proliferative activity against HeLa cells. The anti-angiogenic effect was also shown. Finally, implants composed of digoxin and poly(ε-caprolactone) could be applied as a therapeutic alternative to treat the early stage of cervical cancer, once they were able to locally control the release of this anti-angiogenic and anti-proliferative drug, minimizing its systemic side effects and toxicity.
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Digoxina/administración & dosificación , Sistemas de Liberación de Medicamentos , Poliésteres/química , Neoplasias del Cuello Uterino/tratamiento farmacológico , Inhibidores de la Angiogénesis/administración & dosificación , Inhibidores de la Angiogénesis/química , Inhibidores de la Angiogénesis/farmacología , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Antineoplásicos/farmacología , Química Farmacéutica/métodos , Pollos , Membrana Corioalantoides , Cristalización , Digoxina/química , Digoxina/farmacología , Portadores de Fármacos/química , Implantes de Medicamentos , Liberación de Fármacos , Femenino , Células HeLa , Humanos , Interacciones Hidrofóbicas e HidrofílicasRESUMEN
The temperature control in the processing room is one of the major factors associated with the production of safe food with a satisfactory microbiological quality. A total of 288 samples of skinless chicken breast meat were placed in a cutting room, subjected to four different temperatures (12ºC, 14ºC, 16ºC and 18ºC) and collected to evaluate the influence of the room temperature on the microbiological quality during the cutting and boning of chicken breasts. Aerobic mesophilic microorganisms were counted to evaluate the environmental contamination. In addition, coliforms at 35ºC and 45ºC and Staphylococcus spp. were counted, and an analysis for the presence of staphylococcal enterotoxins and Salmonella spp. was performed to determine the microbiological quality of the meat. The results showed an increase in environmental contamination (P=0.01) with an increase in room temperature. However, no significant differences (PË0.05) were observed in the meat cuts regarding the counts of coliforms at 35ºC and 45ºC, the count of Staphylococcus spp. and the presence of Salmonella spp. Moreover, no staphylococcal enterotoxins were detected in the samples analyzed. Thus, despite increasing the environmental contamination, the increase in the cutting room temperature did not affect the microbiological quality of the final product.(AU)
O controle da temperatura do ambiente de processamento é um dos principais fatores relacionados à produção de alimentos seguros e com qualidade microbiológica. Com o objetivo de avaliar a influência da temperatura ambiente durante o corte e a desossa da carne de frangos sobre a qualidade microbiológica dos produtos finais, foram coletadas 288 amostras de carne de peito de frango sem pele, obtidas em uma sala de cortes climatizada submetida a quatro diferentes temperaturas ambientes (12ºC, 14ºC, 16ºC e 18ºC). Para avaliação da contaminação ambiental, foi realizada a contagem de microrganismos mesófilos aeróbios e, para a avaliação da qualidade microbiológica da carne, foram realizadas a contagem de coliformes totais e termotolerantes, a contagem de Staphylococcus spp., a pesquisa de enterotoxinas estafilocócicas e a pesquisa de Salmonella spp. Os resultados encontrados demonstraram um aumento da contaminação ambiental (P=0,01) à medida que a temperatura da sala foi aumentada. Porém, nos cortes cárneos, não foram observadas diferenças significativas (PË0,05) na contagem de coliformes totais e termotolerantes, na contagem de Staphylococcus spp. e na pesquisa de Salmonella spp. Também não foi detectada a presença de enterotoxinas estafilocócicas nas amostras analisadas. Foi concluído que, apesar da elevação da contaminação ambiental, o aumento da temperatura ambiente da sala de cortes não comprometeu a qualidade microbiológica do produto final.(AU)
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Animales , Enterotoxinas , Contaminación Ambiental , Técnicas Microbiológicas , Aves de Corral , Infecciones Estafilocócicas/veterinaria , Pollos , Microbiología de Alimentos , Carne/análisis , Salmonella , StaphylococcusRESUMEN
Oxidative stress has been correlated with pathologies that impair the performance of athlete horses. The aim of this study was to assess the effects of supplementation with a mixture of polyunsaturated oil and vitamin E on the antioxidant and haematological biomarkers of horses. Horses under maintenance care (n = 6) and horses in training (n = 10) received 100 and 300 ml of the oil mixture respectively. Supplementation was provided for a period of 8 weeks, together with isocaloric inclusion. Blood samples were collected at three time periods (pretest, after 4 weeks and after 8 weeks) to analyse the following: the red blood cell count (RBCc); haemoglobin (Hb); haematocrit (HT); leucocytes; lymphocytes; platelets; the mean corpuscular volume (MCV); the mean corpuscular haemoglobin concentration (MCHC); the standard deviation of the red blood cell distribution width (RDW-SD); the coefficient of variation of the red blood cell distribution width (RDW-CV); glutathione peroxidase (GPx); superoxide dismutase (SOD); uric acid (UrAc); total plasma proteins (TPP); and creatine kinase (CK). After the 8 weeks of supplementation, animals under maintenance care exhibited significant increases in SOD, UrAc, the white blood cell count (WBCc), the RDW-SD and the RDW-CV (p < 0.05). The animals in training exhibited increases in GPx, SOD and UrAc (p < 0.05). In conclusion, supplementation with polyunsaturated oil and vitamin E increases blood antioxidants among animals under maintenance and in training, with different trends, while contributing to the fight against oxidative stress in each group analysed.
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Antioxidantes/metabolismo , Ácidos Grasos Insaturados/farmacología , Caballos/sangre , Vitamina E/farmacología , Animales , Biomarcadores/sangre , Suplementos Dietéticos , Ácidos Grasos Insaturados/administración & dosificación , Femenino , Masculino , Estrés OxidativoRESUMEN
Post-operative endophthalmitis is an infection and an inflammation of the eye following a surgical procedure. Its treatment is based on drug injections into the eye. However, this treatment can lead to ocular complications. Intraocular implants could substitute the conventional therapy. Poly(lactic-co-glycolic acid) (PLGA) implants comprising on vancomycin and dexamethasone were evaluated as drug delivery system to treat endophthalmitis after cataract surgery. Implants were characterized by drug content uniformity, Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Wide Angle X-ray Scattering (WAXS), Scanning Electron Microscopy (SEM) and in vitro drug release. The bactericidal effect of vancomycin, eluted from the implants, was demonstrated against Staphylococcus aureus and Staphylococcus epidermidis. The drugs were uniformly distributed in the polymer. The analytical techniques revealed the chemical integrity of the drugs incorporated into the polymer and the modification of dexamethasone semi-crystalline nature. Drugs were controlled released from implants; and the eluted vancomycin showed bactericidal effects. In conclusion, PLGA implants containing vancomycin and dexamethasone may represent a therapeutic alternative to treat post-operative endophthalmitis.
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Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Antiinflamatorios/administración & dosificación , Antiinflamatorios/uso terapéutico , Bacterias/efectos de los fármacos , Dexametasona/administración & dosificación , Dexametasona/uso terapéutico , Portadores de Fármacos , Ácido Láctico , Ácido Poliglicólico , Infección de la Herida Quirúrgica/prevención & control , Vancomicina/administración & dosificación , Vancomicina/uso terapéutico , Antibacterianos/farmacología , Implantes de Medicamentos , Liberación de Fármacos , Endoftalmitis/microbiología , Endoftalmitis/prevención & control , Humanos , Pruebas de Sensibilidad Microbiana , Procedimientos Quirúrgicos Oftalmológicos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Staphylococcus aureus/efectos de los fármacos , Staphylococcus epidermidis/efectos de los fármacos , Vancomicina/farmacologíaRESUMEN
Com o objetivo de avaliar a qualidade da carne de frangos de corte mediante pesquisa dos níveis de aminas bioativas, foram coletadas, pelos serviços de inspeção oficiais, 160 amostras de carcaças provenientes de cinco regiões distintas do estado de Minas Gerais, durante o período de um ano. As poliaminas (espermidina e espermina) e as aminas biogênicas (putrescina, cadaverina, histamina, tiramina) foram pesquisadas por cromatografia líquida de alta eficiência e detecção ultravioleta (CLAE/UV). Os resultados encontrados demonstraram a presença das poliaminas, espermidina e espermina, em todas as amostras, em concentrações médias de 3,56mg/100g e 5,72mg/100g, respectivamente. Em todas as amostras foram detectadas, em concentrações muito baixas, as aminas putrescina, cadaverina, histamina e tiramina. Foi concluído que a carne de frangos de corte produzida no estado de Minas Gerais é uma fonte de poliaminas, importantes para o crescimento e a proliferação celular, e que os baixos teores de aminas biogênicas encontrados não representam riscos à saúde do consumidor, indicando que esse tipo de carne apresenta boa qualidade, tomando por base o critério de aminas bioativas.
In order to evaluate the meat quality of broiler chickens by searching the bioactive amines level, 160 samples of carcass from the five regions of the Minas Gerais State, were collected during one year by the official inspection service. The poliamines (spermidine and spermine) and the biogenic amines (putrescine, cadaverine, histamine and tyramine) were determined by high performance liquid chromatography with ultraviolet detection (HPLC/UV). The results demonstrated the presence of polyamines spermidine and spermine in all samples, at mean concentrations of 3.56mg/100g and 5.72mg/100g, respectively. The biogenic amines putrescine, cadaverine, histamine and tyramine were also found, but in low concentrations. It was concluded that the chicken broiler meat produced in Minas Gerais state is a source of polyamines, important for growth and cell proliferation; and that the biogenic amine levels found were low, and do not represent risks to consumer health, indicating that it has good quality, based on the criterion of bioactive amine.
Asunto(s)
Animales , Aminas Biogénicas/análisis , Pollos , Poliaminas/aislamiento & purificación , Cromatografía Líquida de Alta Presión/veterinaria , Calidad de los AlimentosRESUMEN
O estudo visou investigar o efeito da suplementação dietética com óleo de palma sobre o perfil sérico lipídico e as características seminais de touros bubalinos (Bubalus bubalis), bem como suas correlações. Doze touros foram alocados no Grupo CONT (n=5) ou Grupo ÓLEO (n=7) e receberam alimentação isoproteica composta por silagem de milho e concentrado (milho triturado, farelo de trigo e ureia), com proporção volumoso/concentrado de 50%, durante 130 dias (Períodos 1 e 2). Diferencialmente, óleo de palma foi adicionado ao concentrado (2% MS) do Grupo ÓLEO. Sêmen e sangue foram colhidos quinzenalmente. Houve aumento nas concentrações séricas de colesterol, HDL e lipídios totais nos animais do Grupo ÓLEO, enquanto o período influenciou nas taxas de colesterol, LDL, lipídios totais e VLDL (P<0,05). Houve decréscimo no turbilhonamento e discreta redução na integridade de membranas nos animais do Grupo ÓLEO (P<0,05). Correlações significativas foram encontradas entre triglicerídeos e defeitos menores (r=-0,412; P=0,006), LDL e defeitos totais (r=-0,333; P=0,030), lipídios totais e defeitos menores (r=-0.366; P= 0,017), lipídios totais e defeitos totais (r=-0.309; P= 0,046), e VLDL e viabilidade espermática (r=0,381; P=0,012), apontando efeitos positivos da maior lipidemia na morfologia e na viabilidade espermática. O uso de óleo de palma alterou o perfil lipídico sérico, mas não favoreceu per se os parâmetros seminais relacionados com o potencial de fertilidade dos touros.
The study aimed to investigate the effect of dietary supplementation with palm oil on serum lipid profile, the seminal characteristics of buffaloes (Bubalus bubalis) and the correlations between them. Twelve bulls were divided into Group CONT (n = 5) or Group OIL (n = 7). Animals in both groups were fed with isoproteic diets composed of corn silage and concentrated (ground corn, wheat bran and urea), with 50% forage/concentrate ratio, during 130 days (Periods 1 and 2). Palm oil (2%DM) was added to diet offered to Group OIL. Semen and blood samples were collected every two weeks. Increased serum levels of cholesterol, HDL and total lipids were observed for Group OIL, while the period influenced on cholesterol, LDL, total lipids and VLDL (P<0,05). Treatment decreased gross motility (P<0.05) and slightly reduced sperm membrane integrity (P<0.05) in animals of Group OIL. There were significant correlations between triglycerides and minor defects (r=-0.412, P=0.006), LDL and total defects (r=-0.333, P=0.030), total lipids and minor defects (r=-0.366, P=0.017), VLDL and spermatic viability (r=0.381, P=0.012), and total lipids and totals defects (r=-0.309, P=0.046), highlighting positive effects of higher lipid serum levels on sperm morphology and viability. The incorporation of palm oil in the diet altered the serum lipid profile, but it showed no positive effect on seminal parameters related to the potential of bull fertility.
Asunto(s)
Animales , Análisis de Semen/veterinaria , Elaeis guineensis/administración & dosificación , Aceites , Búfalos/clasificaciónRESUMEN
Herein we present new occurrences of sites of Dendropsophus minusculus in Brazil adding information about reproductive biology and colour patterns of the species. Such information is fundamental for characterising the species that we believe has been neglected due to its morphological similarity with other congeneric species. Dendropsophus minusculus may be found in different morphoclimatic domains, being one of the most generalist species of the genus in this aspect. The species plasticity is not restricted to its occurrence, but also related to aspects of its reproductive biology, and we hypothesised that the latter feature could explain the wide geographical range of the species. We highlight the importance of further in-depth studies and the use of D. minusculus as a model to understand the historical events responsible for the current geographical distribution of the morphoclimatic domains in Brazil.
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Anuros/anatomía & histología , Anuros/clasificación , Ecosistema , Animales , Anuros/fisiología , BrasilRESUMEN
An HPLC-UV method was developed and validated for the determination of acyclovir in vitreous humor. The method was carried out in isocratic mode using 0.02 mol/L acetic acid/methanol (95:5) as mobile phase, a C18 column at 25 degrees C and UV detection at 254 nm. The method was linear (r2> 0.99) over the range of 35-700 microg/mL, precise (RSD <5%), accurate (recovery ranged from 98.18 to 99.64%), robust, selective regarding of the vitreous humor, and robust remaining unaffected by deliberate variations in relevant parameters. The validated HPLC-UV method can be successfully applied to determine acyclovir directly injected into the vitreous cavity of rabbits' eye.