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1.
Foods ; 13(10)2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38790881

RESUMO

The aims of this study were to describe and compare the meat quality characteristics of male and female kids from the "Serrana" and "Preta de Montesinho" breeds certified as "Cabrito Transmontano" and reinforce the performance of near-infrared reflectance (NIR) spectra in predicting these quality characteristics and discriminating among breeds. Samples of Longissimus thoracis (n = 32; sixteen per breed; eight males and eight females) were used. Breed significantly affected meat quality characteristics, with only color and fatty acid (FA) (C12:0) being influenced by sex. The meat of the "Serrana" breed proved to be more tender than that of the "Preta de Montesinho". However, the meat from the "Preta de Montesinho" breed showed higher intramuscular fat content and was lighter than that from the "Serrana" breed, which favors its quality of color and juiciness. The use of NIR with the linear support vector machine regression (SVMR) classification model demonstrated its capability to quantify meat quality characteristics such as pH, CIELab color, protein, moisture, ash, fat, texture, water-holding capacity, and lipid profile. Discriminant analysis was performed by dividing the sample spectra into calibration sets (75 percent) and prediction sets (25 percent) and applying the Kennard-Stone algorithm to the spectra. This resulted in 100% correct classifications with the training data and 96.7% accuracy with the test data. The test data showed acceptable estimation models with R2 > 0.99.

2.
Molecules ; 29(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38731432

RESUMO

Dairy products are highly susceptible to contamination from microorganisms. This study aimed to evaluate the efficacy of hydroxypropyl methylcellulose (HPMC) and propolis film as protective coatings for cheese. For this, microbiological analyses were carried out over the cheese' ripening period, focusing on total mesophilic bacteria, yeasts and moulds, lactic acid bacteria, total coliforms, Escherichia coli, and Enterobacteriaceae. Physicochemical parameters (pH, water activity, colour, phenolic compounds content) were also evaluated. The statistical analysis (conducted using ANOVA and PERMANOVA) showed a significant interaction term between the HPMC film and propolis (factor 1) and storage days (factor 2) with regard to the dependent variables: microbiological and physicochemical parameters. A high level of microbial contamination was identified at the baseline. However, the propolis films were able to reduce the microbial count. Physicochemical parameters also varied with storage time, with no significant differences found for propolis-containing films. Overall, the addition of propolis to the film influenced the cheeses' colour and the quantification of phenolic compounds. Regarding phenolic compounds, their loss was verified during storage, and was more pronounced in films with a higher percentage of propolis. The study also showed that, of the three groups of phenolic compounds (hydroxybenzoic acids, hydroxycinnamic acids, and flavonoids), hydroxycinnamic acids showed the most significant losses. Overall, this study reveals the potential of using HPMC/propolis films as a coating for cheese in terms of microbiological control and the preservation of physicochemical properties.


Assuntos
Queijo , Conservação de Alimentos , Derivados da Hipromelose , Própole , Queijo/microbiologia , Queijo/análise , Própole/química , Derivados da Hipromelose/química , Conservação de Alimentos/métodos , Fenóis/química , Fenóis/análise , Microbiologia de Alimentos , Escherichia coli/efeitos dos fármacos
3.
Microorganisms ; 11(11)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38004790

RESUMO

Geopropolis has been used in traditional medicine for centuries. In this study, the botanical origin, physicochemical profile, and biological activities of geopropolis from Melipona scutellaris harvested during rainy and dry seasons were investigated. Palynological analysis identified over 50 pollen types, with Schinus terebinthifolius and Cecropia being the predominant types. The analytical results were in line with those reported in the literature. Rainy-season geopropolis exhibited higher total phenol and flavonoid content (determined using High Performance Liquid Chromatography-25.13% and 3.92%, respectively) compared to the dry season (19.30% and 2.09%); the major peaks (naringin, gallic acid, and catechin) were similar among samples. Antioxidant capacity was assessed via DPPH, reducing power, and ß-carotene/linoleic acid discoloration assays. Rainy-season samples displayed superior antioxidant activity across methods. Antimicrobial effects were determined using microdilution, while the impact on the cholinesterase enzyme was quantified using 5-thio-2-nitrobenzoic acid accumulation. Anti-inflammatory and antimutagenic activities were assessed through hyaluronidase enzyme inhibition and by utilizing Saccharomyces cerevisiae ATCC-20113 cells. Both samples exhibited anti-inflammatory and antimutagenic properties. Moreover, a significant inhibition of acetylcholinesterase was observed, with IC50 values of 0.35 µg/mL during the rainy season and 0.28 µg/mL during the dry season. Additionally, the geopropolis displayed antimicrobial activity, particularly against Staphylococcus aureus. These findings suggest the therapeutic potential of M. scutellaris geopropolis in the context of inflammatory, oxidative, and infectious diseases.

4.
Molecules ; 28(12)2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37375400

RESUMO

Propolis is a natural product produced by bees that contains a complex mixture of compounds, including phenolic compounds and flavonoids. These compounds contribute to its biological activities, such as antioxidant capacity. This study analysed the pollen profile, total phenolic content (TPC), antioxidant properties, and phenolic compound profile of four propolis samples from Portugal. The total phenolic compounds in the samples were determined by six different techniques: four different Folin-Ciocalteu (F-C) methods, spectrophotometry (SPECT), and voltammetry (SWV). Of the six methods, SPECT allowed the highest quantification, while SWV achieved the lowest. The mean TPC values for these methods were 422 ± 98 and 47 ± 11 mg GAE/g sample, respectively. Antioxidant capacity was determined by four different methods: DPPH, FRAP, original ferrocyanide (OFec), and modified ferrocyanide (MFec). The MFec method gave the highest antioxidant capacity for all samples, followed by the DPPH method. The study also investigated the correlation between TPC and antioxidant capacity with the presence of hydroxybenzoic acid (HBA), hydroxycinnamic acid (HCA), and flavonoids (FLAV) in propolis samples. The results showed that the concentrations of specific compounds in propolis samples can significantly impact their antioxidant capacity and TPC quantification. Analysis of the profile of phenolic compounds by the UHPLC-DAD-ESI-MS technique identified chrysin, caffeic acid isoprenyl ester, pinocembrin, galangin, pinobanksin-3-O-acetate, and caffeic acid phenyl ester as the major compounds in the four propolis samples. In conclusion, this study shows the importance of the choice of method for determining TPC and antioxidant activity in samples and the contribution of HBA and HCA content to their quantification.


Assuntos
Antioxidantes , Própole , Antioxidantes/química , Própole/química , Ferrocianetos , Flavonoides/análise , Fenóis/química
5.
Phys Chem Chem Phys ; 25(7): 5710-5717, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36734957

RESUMO

closo-Carboranes are structures that have been studied for many decades due to their vast applicability in medicine, catalysis, and energy storage. In order to go deeper into the physics behind the interactions of oppositely charged ions, which have potential applications in electrical energy storage and conversion devices, the present work aims to shed light on the physical nature of the interactions involving (R-CB11H11-, R = H, F, CH3, CF3) and Mq+ = Li+, Na+, Mg2+, Zn2+ ions. The bonding situations are evaluated in light of both canonical Kohn-Sham energy decomposition, EDA-NOCV, and local energy decomposition, LED, analyses. Electron and hole transports are also evaluated through charge transfer integrals. The findings reveal that such complexes present not only more significant electrostatic, but also non-negligible orbital contributions. Both energy decomposition analyses EDA-NOCV and DLPNO-LED confirm that the strength of ionic pair interactions (R-CB11H11- ↔ Mq+) is much more dependent on the nature of the cation employed than on the substituent R used. The results also reveal that charge transfers are not significant in such interacting systems.

6.
Foods ; 12(3)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36766001

RESUMO

This study evaluates the ability of the near infrared reflectance spectroscopy (NIRS) to estimate the aW, protein, moisture, ash, fat, collagen, texture, pigments, and WHC in the Longissimus thoracis et lumborum (LTL) of Bísaro pig. Samples (n = 40) of the LTL muscle were minced and scanned in an FT-NIR MasterTM N500 (BÜCHI) over a NIR spectral range of 4000-10,000 cm-1 with a resolution of 4 cm-1. The PLS and SVM regression models were developed using the spectra's math treatment, DV1, DV2, MSC, SNV, and SMT (n = 40). PLS models showed acceptable fits (estimation models with RMSE ≤ 0.5% and R2 ≥ 0.95) except for the RT variable (RMSE of 0.891% and R2 of 0.748). The SVM models presented better overall prediction results than those obtained by PLS, where only the variables pigments and WHC presented estimation models (respectively: RMSE of 0.069 and 0.472%; R2 of 0.993 and 0.996; slope of 0.985 ± 0.006 and 0.925 ± 0.006). The results showed NIRs capacity to predict the meat quality traits of Bísaro pig breed in order to guarantee its characterization.

7.
Foods ; 12(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38231830

RESUMO

This study involved a comprehensive examination of sensory attributes in dry-cured Bísaro loins, including odor, androsterone, scatol, lean color, fat color, hardness, juiciness, chewiness, flavor intensity and flavor persistence. An analysis of 40 samples revealed a wide variation in these attributes, ensuring a robust margin for multivariate calibration purposes. The respective near-infrared (NIR) spectra unveiled distinct peaks associated with significant components, such as proteins, lipids and water. Support vector regression (SVR) models were methodically calibrated for all sensory attributes, with optimal results using multiplicative scattering correction pre-treatment, MinMax normalization and the radial base kernel (non-linear SVR model). This process involved partitioning the data into calibration (67%) and prediction (33%) subsets using the SPXY algorithm. The model parameters were optimized via a hybrid algorithm based on particle swarm optimization (PSO) to effectively minimize the root-mean-square error (RMSECV) derived from five-fold cross-validation and ensure the attainment of optimal model performance and predictive accuracy. The predictive models exhibited acceptable results, characterized by R-squared values close to 1 (0.9616-0.9955) and low RMSE values (0.0400-0.1031). The prediction set's relative standard deviation (RSD) remained under 5%. Comparisons with prior research revealed significant improvements in prediction accuracy, particularly when considering attributes like pig meat aroma, hardness, fat color and flavor intensity. This research underscores the potential of advanced analytical techniques to improve the precision of sensory evaluations in food quality assessment. Such advancements have the potential to benefit both the research community and the meat industry by closely aligning their practices with consumer preferences and expectations.

8.
Chem Biodivers ; 19(11): e202200698, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36125776

RESUMO

This study successfully applied a potentiometric E-tongue with 20 cross-selectivity lipidic polymeric membranes in the discrimination of three semi-quantitative groups, that represented the following intervals of honey adulteration percentage with cane sugar: 0 %; [0, 10]%; [10, 20]% of adulteration. We analysed five different types of Portuguese honey; five brands of cane sugar were added to the adulterated samples; a comparative analysis was then performed. Linear discriminant analysis coupled with a tabu search algorithm for feature selection was applied to the ETongue's analytical data to select the best model. A discriminant model with 12 sensors was obtained. This model classified correctly all samples in both in internal (train data, 15 samples) and external validation (test data,10 samples). Also, multiple linear regression with tabu search was applied to verify if ETongue's data would allow quantifying the honey's adulteration level. The results showed that it was possible to obtain a quantitative model but with unsatisfactory predictive performance in the test data group (external validation), giving, in general, values below the expected concentrations. E-tongue is a real-time green, flexible and low-cost analytical tool that requires minimum sample preparation and no special technical skills, being a promising tool for everyday application.


Assuntos
Mel , Mel/análise , Bengala , Contaminação de Alimentos/análise , Análise Discriminante , Sacarose
9.
J Chem Inf Model ; 62(19): 4702-4712, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36122418

RESUMO

Ionic liquids have attracted the attention of researchers as possible electrolytes for electrochemical energy storage devices. However, their properties, such as the electrochemical stability window (ESW), ionic conductivity, and diffusivity, are influenced both by the chemical structures of cations and anions and by their combinations. Most studies in the literature focus on the understanding of common ionic liquids, and little effort has been made to find ways to improve our atomistic understanding of those systems. The goal of this paper is to explore the structural characteristics of cations and anions that form ionic liquids that can expand the HOMO/LUMO gap, a property directly linked to the ESW of the electrolyte. For that, we design a framework for randomly generating new ions by combining their fragments. Within this framework, we generate about 104 cations and 104 anions and fully optimize their structures using density functional theory. Our calculations show that aromatic cations are less stable ionic liquids than aliphatic ones, an expected result if chemical rationale is used. More importantly, we can improve the gap by adding electron-donating and electron-withdrawing functional groups to the cations and anions, respectively. The increase can be about 2 V, depending on the case. This improvement is reflected in a wider ESW.

10.
PLoS One ; 17(8): e0269313, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36018880

RESUMO

INTRODUCTION: The aim of this study was to describe and evaluate a novel plate designed specifically for the canine ilium using finite element methods. The cranial portion of the plate had an elliptical shape and contained nine screw holes. The caudal portion of the plate was triangular with three screw holes. Four and three screws were used at the cranial (screw 1 to 4) and caudal (screw 5 to 7) segment of the plate. Finite element models of the plate and canine pelvis were created. A load of 300 N was applied on the femur-hip joint contact area. Values of Von Mises Stress on the plate, screws and the maximum and minimum main stresses in the bone were used to capture the mechanical factors in this study. RESULTS: The novel implant had a plate stress of 51.9 megapascals (MPa) with higher stress in the dorsal part of the plate. Screws 2 and 4 showed similar stress values of 17.3 MPa. Screws 1 and 3 were the most loaded (51.9 MPa and 75 MPa, respectively). Screws 5, 6, and 7 showed similar dissipation and stress values (21.55 MPa). There was traction force in the dorsal region of the pubis and compression in the ventral part, with dissipation and values of 15.4 MPa and 23.9 MPa, respectively, acquiring balance between them. CONCLUSION: The novel plate is potentially applicable and specifically suitable for iliac fractures in dogs. The screws distribution modeled proved itself strategical since the simulated stresses were evenly distributed throughout the implant construct.


Assuntos
Fixação Interna de Fraturas , Fraturas da Coluna Vertebral , Animais , Fenômenos Biomecânicos , Placas Ósseas , Parafusos Ósseos , Cães , Análise de Elementos Finitos , Estresse Mecânico
11.
Talanta ; 226: 122122, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33676677

RESUMO

An electronic nose, comprising nine metal oxide sensors, has been built aiming to classify olive oils according to the fruity intensity commercial grade (ripely fruity or light, medium and intense greenly fruity), following the European regulated complementary terminology. The lab-made sensor device was capable to differentiate standard aqueous solutions (acetic acid, cis-3-hexenyl, cis-3-hexen-1-ol, hexanal, 1-hexenol and nonanal) that mimicked positive sensations (e.g., fatty, floral, fruit, grass, green and green leaves attributes) and negative attributes (e.g., sour and vinegary defects), as well as to semi-quantitatively classify them according to the concentration ranges (0.05-2.25 mg/kg). For that, unsupervised (principal component analysis) and supervised (linear discriminant analysis: sensitivity of 92% for leave-one-out cross validation) classification multivariate models were established based on nine or six gas sensors, respectively. It was also showed that the built E-nose allowed differentiating/discriminating (sensitivity of 81% for leave-one-out cross validation) extra virgin olive oils according to the perceived intensity of fruitiness as ripely fruity, light, medium or intense greenly fruity. In conclusion, the gas sensor device could be used as a practical preliminary non-destructive tool for guaranteeing the correctness of olive oil fruitiness intensity labelling.

12.
Res Vet Sci ; 133: 180-187, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32992129

RESUMO

The present study established multiple linear regression models using two ultrasound in vivo measurements (at lumbar and sternal regions, with different real-time ultrasonography machines and probes) and live weight, to predict simultaneously carcass composition and body fat depots of different breeds of sheep and goat. This study is important for the small ruminant industry, considering the feasibility of using the ultrasound methodology in field conditions, as well as an online system of the carcass evaluation. The multiple linear regression models were obtained by selecting the best subset of variables between using the in vivo measurements (raw variables), their second degree and interactions, evaluated in terms of prediction performance using cross-validation "K-folds" and validated by a test group. Overall, high accuracy (adj R2) was obtained from the linear relationship between predicted and experimental values of the group test for each of the nine dependent variables, with values varying between adj R2 0.88 and 0.98.


Assuntos
Tecido Adiposo , Criação de Animais Domésticos/métodos , Composição Corporal , Peso Corporal , Cabras/anatomia & histologia , Ovinos/anatomia & histologia , Ultrassonografia/veterinária , Criação de Animais Domésticos/instrumentação , Animais , Cruzamento , Modelos Lineares , Masculino , Análise Multivariada , Reprodutibilidade dos Testes , Ultrassonografia/instrumentação , Ultrassonografia/normas
13.
Talanta ; 208: 120364, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816761

RESUMO

The identification of more than three perfumes is difficult and no analytical tool can completely replace the human olfactory system for fragrance classification. Indeed, no analytical system can mimic the human fragrance perception, being the recognition of perfume aroma patterns by conventional or sensor-based analytical tools a challenging task. For the perfume sector, the possibility of applying fast, cost-effective and green analytical devices for perfume analysis would represent a huge economic revenue. Since the perfume aroma pattern will depend on the composition of the liquid phase and on the diffusion properties of their volatile components, this work aimed to apply a potentiometric electronic tongue, comprising non-specific cross-sensitive lipid polymeric membranes, combined with chemometric techniques, as a novel perfume classifier. The multisensors device allowed establishing perfumes' unique fingerprints, which were successfully used to discriminate men from women perfumes, to identify the perfume aroma family (Citric-Aromatic, Floral, Floral-Fruity, Floral-Oriental, Floral-Woody, Woody-Oriental and Woody-Spicy) and, assessing the perfume storage time-period (≤ 9 months; 9-24 months; and, ≥ 24 months). The established linear discriminant models were based on single-run potentiometric profiles gathered by sub-sets of sensors selected using the simulated annealing algorithm, which enabled achieving correct classification rates of 93-100% (for leave-one-out cross-validation procedure). The satisfactory performance of the electronic tongue demonstrates the versatility of the proposed approach as a practical perfume preliminary classifier sensor device, which industrial application may be foreseen in a near future, contributing to a green-sustained economic growth of the perfume industry.

14.
Microorganisms ; 7(10)2019 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-31569525

RESUMO

Mead is a traditional beverage that results from the alcoholic fermentation of diluted honey performed by yeasts. Although the process of mead production has been optimized in recent years, studies focused on its sensory properties are still scarce. Therefore, the aim of this work was to analyse the sensory attributes of mead produced with free or immobilized cells of the Saccharomyces cerevisiae strains QA23 and ICV D47, and to establish potential correlations with its volatile composition. In the volatile composition of mead, the effect of yeast condition was more important than the strain. In respect to sensory analysis, the most pleasant aroma descriptors were correlated with mead obtained with free yeast cells, independently of the strain. Both sensory analysis and volatile composition indicates that the most pleasant mead was produced by free yeast cells. Although this study has provided a significant contribution, further research on the sensory quality of mead is still needed.

15.
PLoS One ; 14(8): e0220291, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31381582

RESUMO

The objective of this study was to evaluate the use of a lyophilized and gamma-sterilized allogeneic freeze-dried bone wedge as a spacer for advancement of a modified tibial tuberosity (mTTA) in 16 knees that were clinically diagnosed with cranial cruciate ligament disease. Patients underwent radiography before the surgical procedure as well as immediately after surgery and at 30, 60, 90 and 120 days post-surgery, and their locomotion was evaluated at the same time points except for the immediate postoperative period. The surgical wounds were evaluated for signs of infection and rejection of the bone implant. Locomotion was graded on a scale of 0-5, with 0 indicating no limping and 5 indicating limb functional impotence. The "tibial-tibial bone-tibial implant" interfaces were evaluated radiographically, and each interface was assigned scores of 0-3, with 0 indicating no contact between the implant and adjacent bone and 3 indicating a bone bridge throughout the interface. The patients showed good clinical and radiographic recovery. The lyophilized bone spacer allowed for easy storage and transport and rapid and satisfactory execution of mTTA while showing resistance to drilling and fixation with screws in 87.5% of cases and a mean surgical time of 45.9 minutes. No immunogenic reactions were observed in 93.7% of the cases. One patient presented infection of the surgical focus, which showed remission after antimicrobial therapy. All patients showed functional recovery of the operated limb, with the number of clinically healthy patients being higher than those with claudication at 120 days (p ≤ 0.05). In all patients, it was possible to verify the incorporation of the bone implant into the tibia. Bone union occurred progressively, and the degrees of bone union observed on radiographs at postoperative days 60, 90, and 120 were significantly greater (p < 0.05) than those observed in the immediate postoperative period and at 30 days.


Assuntos
Aloenxertos , Lesões do Ligamento Cruzado Anterior/cirurgia , Transplante Ósseo , Raios gama , Osteotomia/métodos , Esterilização , Tíbia/cirurgia , Aloenxertos/efeitos da radiação , Animais , Lesões do Ligamento Cruzado Anterior/fisiopatologia , Cães , Liofilização , Recuperação de Função Fisiológica , Resultado do Tratamento
16.
J Mol Model ; 25(9): 263, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31428870

RESUMO

The USFDA has approved pramlintide, commercially named Symlin (sIAPP), as adjunctive therapy for type 2 diabetes (T2D). This analogue of the human amylin peptide (hIAPP) has triple proline substitutions typical of the rat isoform (rIAPP). Recently, it was proposed that pramlintide solubility and aggregation resistance might be improved by incorporating further mutations, as S20R, screened from the wild-type porcine isoform (pIAPP), which leads to the variant named sIAPP+. To better elucidate how such properties might be systematically induced in rationally designed analogues, we performed comparative assessments of rIAPP, sIAPP, and sIAPP+ using replica-exchange molecular dynamics (REMD) with an accurate combination of force field Charmm22* and explicit aqueous solvation TIP4P/Ew. Our thermo-structural analyses show that sIAPP exhibits a thermal conversion channel of helices[Formula: see text]-sheets resembling hIAPP. This channel is depleted in rIAPP and is absent in sIAPP+. As a consequence, sIAPP+ presents an overall decrease of ß-like secondary structures and an overstabilization of α-helices. Additionally, we observed in rIAPP and sIAPP+ an increase in the backbone RMSF of molecular terminals and the exposed area of key residues. These structural features of sIAPP+ suggest a nonamyloidogenic character, which is corroborated by our judicious estimate of the electrostatic component of the solvation free energy using a generalized Born model, and so it may constitute an alternative strategy to sIAPP as a peptide analogue of hIAPP. Furthermore, our findings confirm that different aggregation propensities of amylin and its analogues are synergistically modulated by long-range effects of key mutations. Graphical Abstract S20R-Pramlintide.


Assuntos
Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Simulação de Dinâmica Molecular , Mutação , Agregação Patológica de Proteínas , Animais , Humanos , Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Polipeptídeo Amiloide das Ilhotas Pancreáticas/genética , Estrutura Secundária de Proteína , Ratos , Água/química
17.
Pesqui. vet. bras ; 39(8): 643-648, Aug. 2019. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1040730

RESUMO

Canine hip dysplasia (CHD) is a common condition observed in the surgical clinics for small animals. Among the surgical techniques for management of CHD, triple pelvic osteotomy and sacroiliac wedge promote acetabular lateral axial rotation (ventroversion), increasing acetabular coverage and joint stability. The present study aimed to evaluate radiographically, by measuring the Norberg angle (NA) and the acetabular coverage percentage (ACP), the acetabular ventroversion induced by the sacroiliac wedge technique, with or without pelvic osteotomies; we also checked the feasibility of wedges made of polyamide with an angulation of 20° and 30°. The software used to measure NA and ACP was AutoCAD® 2009. Pelves from 10 canine corpses were evaluated radiographically at four time-points: M0 (Control Group), M1 (wedges of 20° and 30°), M2 and M3 (wedges associated with bilateral pubis and ischium osteotomies, respectively). There was no significant increase in the acetabular ventroversion at M1, M2, and M3. The polyamide sacroiliac wedge technique proved to be feasible, stable, and easy to apply. Further, the software proved to be efficient and easy to use for NA and ACP measurements. In the present study, even in the cases of non-dysplasic adult canine corpses, it was concluded that the sacroiliac wedge technique does not require to be accompanied by pubis and ischial osteotomies because they did not significantly increase the NA and ACP.(AU)


A displasia coxofemoral (DCF) é afecção comum na clínica cirúrgica de pequenos animais. Entre as técnicas cirúrgicas para controle da DCF, a osteotomia pélvica tripla (OPT) e a cunha sacroilíaca (CSI), promovem rotação lateral acetabular no eixo axial (ventroversão), aumentando a cobertura acetabular e a estabilidade da articulação. Desta forma, o presente estudo objetivou avaliar radiograficamente, por meio da aferição do ângulo de Norberg (NA) e da porcentagem de cobertura acetabular (PCA), a ventroversão acetabular induzida pela técnica da cunha sacroilíaca, associada ou não às osteotomias pélvicas, além de verificar a exequibilidade das cunhas confeccionadas de poliamida com angulação de 20ο e 30ο. O software utilizado para aferir o AN e o PCA foi o AutoCAD® 2009. Dez pelves de cadáveres caninos foram avaliadas radiograficamente em quatro momentos: MO (Grupo Controle), M1 (cunhas de 20ο e 30ο), M2 e M3 (cunhas associadas à osteotomia bilateral do púbis e ísquio, respectivamente). Não houve aumento significativo da ventroversão em M1, M2 e M3. A técnica de cunha sacroilíaca de poliamida mostrou-se exequível, estável e de fácil aplicação. Não obstante, o software utilizado mostrou-se eficiente e de fácil utilização nas aferições do AN e PCA. Neste estudo, mesmo tratando-se de cadáveres de cães adultos e de maioria não displásicos, concluiu-se que a utilização da técnica de cunha sacroilíaca não necessita de associação à ostectomia púbica e a osteotomia do ísquio por não promoverem aumento significativo do AN e da PCA.(AU)


Assuntos
Animais , Cães , Osteotomia/veterinária , Articulação Sacroilíaca/cirurgia , Displasia Pélvica Canina/diagnóstico , Articulação do Quadril/cirurgia , Cadáver
18.
Vet Comp Orthop Traumatol ; 32(3): 234-240, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30943549

RESUMO

OBJECTIVE: The aim of this study was to compare in vitro accuracy of femoral measurements obtained from different radiographical positions with actual femoral anatomical dimensions in dogs. MATERIALS AND METHODS: Craniocaudal projections of the femur in ventrodorsal position, standard craniocaudal radiographical (SR) and craniocaudal radiography with horizontal radiographical beam (HR), in addition to anatomical macroscopic measurements (A), were obtained from 45 femurs from 23 canine cadavers, for calculation of the canal flare index (CFI). The differences between the radiographical positions and 95% limits of agreement (LOA) between the CFI-SR, CFI-HR and CFI-A were evaluated by the Bland-Altman method. RESULTS: The standard craniocaudal radiograph provided an approximate dimension of the proximal femoral morphology (mean difference: 0.121 ± 0.391) with a different CFI value (p = 0.0341) from CFI-A. The craniocaudal radiograph taken using a horizontal beam provided greater accuracy (mean difference: 0.087 ± 0.42) in our study. CLINICAL SIGNIFICANCE: The craniocaudal projection using a horizontal radiographical beam was more accurate than the standard craniocaudal projection for measurement of the true anatomical dimensions of the canine femur, minimizing the influence of the technique on the CFI values.


Assuntos
Cães/anatomia & histologia , Fêmur/diagnóstico por imagem , Radiografia/veterinária , Animais , Cadáver , Feminino , Masculino , Radiografia/métodos
19.
Food Chem Toxicol ; 128: 202-211, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30991128

RESUMO

Myclobutanil is a chiral triazole fungicide that is employed worldwide. Although enantiomers have the same physical-chemical properties, they may differ in terms of activity, metabolism, and toxicity. This investigation consisted of in vitro enantioselective metabolism studies that employed a human model to assess the risks of myclobutanil in humans. A LC-MS/MS enantioselective method was developed and validated. The enzymatic kinetic parameters (VMAX, KMapp, and CLINT) determined for in vitro rac-myclobutanil and S-(+)-myclobutanil metabolism revealed enantioselective differences. Furthermore, human CYP450 enzymes did not metabolize R-(-)-myclobutanil. The predicted in vivo toxicokinetic parameters indicated that S-(+)-myclobutanil may be preferentially eliminated by the liver and suffer the first-pass metabolism effect. However, because CYP450 did not metabolize R-(-)-myclobutanil, this enantiomer could reach the systemic circulation and stay longer in the human body, potentially causing toxic effects. The CYP450 isoforms CYP2C19 and CYP3A4 were involved in rac-myclobutanil and S-(+)-myclobutanil metabolism. Although there were differences in the metabolism of the myclobutanil enantiomers, in vitro inhibition studies did not show significant enantioselective differences. Overall, the present investigation suggested that myclobutanil moderately inhibits CYP2D6 and CYP2C9 in vitro and strongly inhibits CYP3A and CYP2C19 in vitro. These results provide useful scientific information for myclobutanil risk assessment in humans.


Assuntos
Inibidores das Enzimas do Citocromo P-450/toxicidade , Sistema Enzimático do Citocromo P-450/metabolismo , Fungicidas Industriais/toxicidade , Nitrilas/toxicidade , Triazóis/toxicidade , Cromatografia Líquida , Inibidores das Enzimas do Citocromo P-450/farmacocinética , Fungicidas Industriais/farmacocinética , Humanos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Nitrilas/química , Nitrilas/farmacocinética , Reprodutibilidade dos Testes , Estereoisomerismo , Espectrometria de Massas em Tandem , Toxicocinética , Triazóis/química , Triazóis/farmacocinética
20.
Talanta ; 197: 363-373, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30771949

RESUMO

Olive oil is highly appreciated due to its nutritional and organoleptic characteristics. However, a huge compositional variation is observed between olive oils, requiring the use of diverse analytical techniques for its classification including titration, spectrophotometry and chromatography, as well as sensory analysis. Chemical analysis is usually time-consuming, expensive and require skilled technicians, while the sensorial ones are dependent upon individual subjective evaluations, even if performed by trained panellists. This work evaluated and demonstrated the feasibility of using a potentiometric electronic tongue, comprising non-specific lipid polymeric and cross-sensitive sensor membranes, coupled with chemometric tools based on different sub-sets of sensors (from 11 to 14 sensors), to predict key quality parameters of olive oils based on single-run assays. The multivariate linear models established for 23 centenarian olive trees from different cultivars allowed predicting peroxide value, oxidative stability, total phenols and tocopherols contents, CIELAB scale parameters (L*, a* and b* values), as well as 11 gustatory-retronasal positive attributes (green, sweet, bitter, pungent, tomato and tomato leaves, apple, banana, cabbage, fresh herbs and dry fruits) with satisfactory accuracy (0.90 ±â€¯0.07 ≤ R2 ≤ 0.98 ±â€¯0.02 for the repeated K-fold-CV procedure, which ensured that 25% of the data was used for internal-validation purposes). The electronic tongue device had an accuracy statistically similar to that achieved with standard analytical techniques, pointing out the versatility of the device for the fast and simultaneous chemical and sensory analysis of olive oil.


Assuntos
Nariz Eletrônico , Azeite de Oliva/análise , Azeite de Oliva/química , Físico-Química , Potenciometria
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