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1.
Food Chem ; 460(Pt 1): 140504, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39033634

RESUMO

Greening of tuna metmyoglobin (MetMb) by thermal treatment (TT) and free cysteine is associated with sulfmyoglobin (SulfMb) production. This greening reaction (GR) was once thought to occur only in tuna species. However, recent research has revealed that not all tuna species exhibit this behavior, and it can also occur in horse MetMb. Thus, the present study aimed to compare the GR-reactive (Katsuwonus pelamis and Equus caballus) and GR-unreactive (Sarda chiliensis and Euthynnus lineatus) MetMb using UV-vis spectrometry during TT (60 °C/30 min and free cysteine) to monitor the GR. We used molecular dynamics (MD) simulation to assess the stability of the heme group during TT. We discovered that using GR-unreactive MetMb resulted in an incomplete GR without producing SulfMb. Additionally, our MD simulations indicated that Met85 presence in the heme cavity from GR-unreactive is responsible for the heme group instability and displacement of distal His during TT.


Assuntos
Temperatura Alta , Simulação de Dinâmica Molecular , Mioglobina , Atum , Animais , Mioglobina/química , Cavalos , Proteínas de Peixes/química , Heme/química
2.
Braz. J. Anesth. (Impr.) ; 73(6): 775-781, Nov.Dec. 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1520388

RESUMO

Abstract Background: Early identification of patients at risk of AKI after cardiac surgery is of critical importance for optimizing perioperative management and improving outcomes. This study aimed to identify the association between preoperative myoglobin levels and postoperative acute kidney injury (AKI) in patients undergoing valve surgery or coronary artery bypass graft surgery (CABG) with cardiopulmonary bypass. Methods: This retrospective study included 293 patients aged over 17 years who underwent valve surgery or CABG with cardiopulmonary bypass. We excluded 87 patients as they met the exclusion criteria. Therefore, 206 patients were included in the final analysis. The patients' demographics as well as intraoperative and postoperative data were collected from electronic medical records. AKI was defined according to the Acute Kidney Injury Network classification system. Results: Of the 206 patients included in this study, 77 developed AKI. The patients who developed AKI were older, had a history of hypertension, underwent valve surgery with concomitant CABG, had lower preoperative hemoglobin levels, and experienced prolonged extracorporeal circulation (ECC) times. Multivariate logistic regression analysis revealed that preoperative myoglobin levels and ECC time were correlated with the development of AKI. A higher preoperative myoglobin level was an independent risk factor for the development of cardiac surgery-associated AKI. Conclusions: Higher preoperative myoglobin levels may enable physicians to identify patients at risk of developing AKI and optimize management accordingly.


Assuntos
Humanos , Idoso , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/epidemiologia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Ponte Cardiopulmonar/efeitos adversos , Fatores de Risco , Mioglobina
3.
Food Res Int ; 174(Pt 2): 113675, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37981368

RESUMO

Despite the relatively high occurrence of bovine meat with intermediate to high ultimate pH (pHu), there is a lack of studies focused on the effects of long-term conventional air-blasting freezing storage on quality parameters of commercial beefs of Zebu Nellore (Bos indicus) with varying pHu ranges. The objective of this work was to evaluate the influence of pHu ranges [normal (≤5.79), intermediate (5.80 to 6.19), and high (≥6.20)] and long-term frozen storage on quality parameters of aged Longissimus dorsi beefs of Zebu Nellore (Bos indicus). The aging conditions were set at 2 °C for 14 days, while the freezing conditions were set at - 20 °C, and samples were collected after 3, 6, 9, and 12 months of storage. The results indicated that the pHu influenced meat quality parameters, as well as the chemical forms of myoglobin, which changed throughout the frozen storage, leading to a brighter red color, especially for the normal pHu beef samples, likely due to increased oxymyoglobin content. Frozen storage improved tenderness, with high pHu beef samples being the more tender after 12 months, potentially due to lower protein oxidation, as measured by the carbonyl content. Increased drip loss was observed over freezing time, with a concomitant decrease in protein solubility, especially for myofibrillar and sarcoplasmic proteins, which differed among the pHu ranges. These findings are valuable for determining freezing time as a preservation strategy to maintain beef quality within different pHu ranges.


Assuntos
Carne , Músculos Paraespinais , Animais , Bovinos , Congelamento , Solubilidade , Concentração de Íons de Hidrogênio
4.
J Agric Food Chem ; 71(46): 17485-17493, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37943570

RESUMO

Myoglobin is the main factor responsible for muscle pigmentation in tuna; muscle color depends upon changes in the oxidative state of myoglobin. The tuna industry has reported muscle greening after thermal treatment involving metmyoglobin (MetMb), trimethylamine oxide (TMAO), and free cysteine (Cys). It has been proposed that this pigmentation change is due to a disulfide bond between a unique cysteine residue (Cys10) found in tuna MetMb and free Cys. However, no evidence has been given to confirm that this reaction occurs. In this review, new findings about the mechanism of this greening reaction are discussed, showing evidence of how free radicals produced from Cys oxidation under thermal treatment participate in the greening of tuna and horse muscle during thermal treatment. In addition, the reaction conditions are compared to other green myoglobins, such as sulfmyoglobin, verdomyoglobin, and cholemyoglobin.


Assuntos
Cisteína , Mioglobina , Animais , Cavalos , Mioglobina/química , Cisteína/química , Metamioglobina/química , Oxirredução , Músculos/metabolismo
5.
J Inorg Biochem ; 247: 112313, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37467661

RESUMO

The interactions of the heme iron of hemeproteins with sulfide and disulfide compounds are of potential interest as physiological signaling processes. While the interaction with hydrogen sulfide has been described computationally and experimentally, the reaction with disulfide, and specifically the molecular mechanism for ligand binding has not been studied in detail. In this work, we study the association process for disulfane and its conjugate base disulfanide at different pH conditions. Additionally, by means of advanced sampling techniques based on multiple steered molecular dynamics, we provide free energy profiles for ligand migration for both acid/base species, showing a similar behavior to the previously reported for the related H2S/HS¯ pair. Finally, we studied the ligand interchange reaction (H2O/H2S, HS¯ and H2O/HSSH, HSS¯) by means of hybrid quantum mechanics-molecular mechanics calculations. We show that the anionic species are able to displace more efficiently the H2O bound to the iron, and that the H-bond network in the distal cavity can help the neutral species to perform the reaction. Altogether, we provide a molecular explanation for the experimental information and show that the global association process depends on a fine balance between the migration towards the active site and the ligand interchange reaction.


Assuntos
Hemeproteínas , Hemeproteínas/química , Metamioglobina/química , Dissulfetos , Ligantes , Sulfetos/metabolismo , Ferro
6.
Meat Sci ; 203: 109231, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37263032

RESUMO

The effects of ultrasound (US) on myoglobin modification, nitrous pigment formation, color, and total and free sulfhydryl content in nitrite-free pork meat batter were assessed. Five treatments were elaborated: Control (without US); TUS10'12 and TUS20'12 (sonication at 25 kHz, at 12 °C for 10 and 20 min, respectively); TUS10'18 and TUS20'18 (sonication at 25 kHz, at 18 °C for 10 and 20 min, respectively). Sonication for 20 min at 12 °C increased OxyMb and DeoxyMb pigments while reducing MetMb levels. This US condition also yielded higher red color indices and lower yellow color indices. Moreover, TUS20'12 exhibited enhanced nitrous pigment formation and decreased FerrylMb and free sulfhydryl (SH) values, indicating reduced oxidation in OxyMb and DeoxyMb pigments. In conclusion, the findings demonstrate that US can impart a cured color to nitrite-free meat products.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Suínos , Nitritos , Carne de Porco/análise , Mioglobina/metabolismo , Oxirredução
7.
J Inorg Biochem ; 245: 112256, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37244768

RESUMO

The mechanism of the metal centered reduction of metmyoglobin (MbFeIII) by inorganic disulfide species has been studied by combined spectroscopic and kinetic analyses, under argon atmosphere. The process is kinetically characterized by biexponential time traces, for variable ratios of excess disulfide to protein, in the pH interval 6.6-8.0. Using UV-vis and resonance Raman spectroscopies, we observed that MbFeIII is converted into a low spin hexacoordinated ferric complex, tentatively assigned as MbFeIII(HSS-)/MbFeIII(SS2-), in an initial fast step. The complex is slowly converted into a pentacoordinated ferrous form, assigned as MbFeII according to the resonance Raman records. The reduction is a pH-dependent process, but independent of the initial disulfide concentration, suggesting the unimolecular decomposition of the intermediate complex following a reductive homolysis. We estimated the rate of the fast formation of the complex at pH 7.4 (kon = 3.7 × 103 M-1 s-1), and a pKa2 = 7.5 for the equilibrium MbFeIII(HSS-)/MbFeIII(SS2-). Also, we estimated the rate for the slow reduction at the same pH (kred = 10-2 s-1). A reaction mechanism compliant with the experimental results is proposed. This mechanistic study provides a differential kinetic signature for the reactions of disulfide compared to sulfide species on metmyoglobin, which may be considered in other hemeprotein systems.


Assuntos
Hemeproteínas , Metamioglobina , Metamioglobina/química , Metamioglobina/metabolismo , Dissulfetos , Análise Espectral , Hemeproteínas/metabolismo , Ferro , Oxirredução , Cinética
8.
Food Chem ; 408: 135165, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36527926

RESUMO

The meat greening is an abnormal pigmentation related to microbiological contamination and lipid oxidation during storage. This color change results from sulfmyoglobin (SulfMb) production promoted by the reaction between metmyoglobin (MetMb), H2O2, and thiol compounds. Spectral studies on cooked meat suggested the production of SulfMb, probably due to the increment of free radicals during thermal treatment. Thus, we evaluated the involvement of free radicals and heme iron in the SulfMb production from horse MetMb and free cysteine (Cys) during thermal treatment. The results confirm that the reaction of SulfMb production at meat muscle pH (5.7-7.2) during heat treatment is a product of free radicals formed from Cys oxidation (SH) and reactive oxygen species (O2-, H2O2). This is catalyzed by the release of heme iron, thus promoting a consecutive reaction having MbFe(IV)O as a reaction intermediate.


Assuntos
Cisteína , Peróxido de Hidrogênio , Animais , Cavalos , Peróxido de Hidrogênio/química , Mioglobina/química , Metamioglobina/química , Radicais Livres , Oxirredução , Ferro/química , Heme
9.
Braz J Anesthesiol ; 73(6): 775-781, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34627830

RESUMO

BACKGROUND: Early identification of patients at risk of AKI after cardiac surgery is of critical importance for optimizing perioperative management and improving outcomes. This study aimed to identify the association between preoperative myoglobin levels and postoperative acute kidney injury (AKI) in patients undergoing valve surgery or coronary artery bypass graft surgery (CABG) with cardiopulmonary bypass. METHODS: This retrospective study included 293 patients aged over 17 years who underwent valve surgery or CABG with cardiopulmonary bypass. We excluded 87 patients as they met the exclusion criteria. Therefore, 206 patients were included in the final analysis. The patients... demographics as well as intraoperative and postoperative data were collected from electronic medical records. AKI was defined according to the Acute Kidney Injury Network classification system. RESULTS: Of the 206 patients included in this study, 77 developed AKI. The patients who developed AKI were older, had a history of hypertension, underwent valve surgery with concomitant CABG, had lower preoperative hemoglobin levels, and experienced prolonged extracorporeal circulation (ECC) times. Multivariate logistic regression analysis revealed that preoperative myoglobin levels and ECC time were correlated with the development of AKI. A higher preoperative myoglobin level was an independent risk factor for the development of cardiac surgery-associated AKI. CONCLUSIONS: Higher preoperative myoglobin levels may enable physicians to identify patients at risk of developing AKI and optimize management accordingly.


Assuntos
Injúria Renal Aguda , Procedimentos Cirúrgicos Cardíacos , Humanos , Idoso , Estudos Retrospectivos , Mioglobina , Ponte Cardiopulmonar/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Fatores de Risco , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia
10.
Molecules ; 27(15)2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35897951

RESUMO

Cardiovascular diseases are considered one of the leading causes of premature mortality of patients worldwide. Therefore, rapid diagnosis of these diseases is crucial to ensure the patient's survival. During a heart attack or severe muscle damage, myoglobin is rapidly released in the body to constitute itself as a precise biomarker of acute myocardial infarction. Thus, we described the photoelectrochemical immunosensor development to detect myoglobin. It was based on fluorine-doped tin oxide modified with CdSeS/ZnSe quantum dots and barium titanate (BTO), designated as CdSeS/ZnSQDS/BTO. It was characterized by scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDX), transmission electron microscopy (TEM), X-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS), and amperometry. The anodic photocurrent at the potential of 0 V (vs. Ag/AgCl) and pH 7.4 was found linearly related to the myoglobin (Mb) concentration from 0.01 to 1000 ng mL-1. Furthermore, the immunosensor showed an average recovery rate of 95.7-110.7% for the determination of myoglobin.


Assuntos
Técnicas Biossensoriais , Compostos de Cádmio/química , Pontos Quânticos , Compostos de Selênio/química , Sulfatos/química , Bário , Biomarcadores , Técnicas Biossensoriais/métodos , Compostos de Cálcio , Humanos , Imunoensaio/métodos , Mioglobina/química , Óxidos , Pontos Quânticos/química , Sulfetos , Titânio , Compostos de Zinco
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 267(Pt 2): 120602, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34801390

RESUMO

In this work, an innovative approach using K-means and multivariate curve resolution-purity based algorithm (MCR-Purity) for the evaluation and quantification of carboxymyoglobin (Mb-CO) formation from Deoxy-Myoglobin (Deoxy-Mb) was presented. Through a multilevel multifactor experimental design, samples with different concentrations of Mb-CO were created. The UV-Vis spectra of these samples were submitted to K-means analysis, finding 3 clusters. The mean spectra of the clusters were extracted and it was possible to detect 2 totally differentiable groups through peaks 423 and 434 nm, which are wavelengths related to the Mb-CO and Deoxy-Mb components, respectively. The spectral data were subjected to MCR-Purity analysis. The MCR-Purity result successfully described the analyzed reaction, explaining more than 99.9% of the variance (R2) with a LOF of 1.43%. Then, a predictive model of MbCO was created through the linear relationship between MCR-Purity contributions and known concentrations of MbCO. The performance parameters of the created predictive model were R2CV = 0.98, RMSECV = 0.58 and RPDcv = 7.8 for the training set, and R2P = 0.98, RMSEP = 0.7 and RPDp = 6.8 for the test set. Thus, the predictive model presented an excellent performance considering that the Mb-CO variation is comprised between 0 and 21 µM. Therefore, these results demonstrate that the application of the proposed strategy to the analysis of spectral data presenting overlapping bands is feasible and robust.


Assuntos
Quimiometria , Mioglobina , Análise Multivariada , Análise Espectral
12.
Arq. bras. med. vet. zootec. (Online) ; 73(1): 214-222, Jan.-Feb. 2021. tab
Artigo em Português | VETINDEX, LILACS | ID: biblio-1153052

RESUMO

Objetivou-se avaliar a influência da suplementação com minerais biocomplexados sobre a qualidade da carne de frangos da linhagem Label Rouge, de ambos os sexos, criados em sistema alternativo. O delineamento experimental foi inteiramente ao acaso (DIC), disposto em esquema fatorial (3x2), sendo três dietas (controle; 0,50ppm de selênio; 0,40ppm de cromo) e dois sexos. Para a estabilidade lipídica, foi utilizado o DIC, disposto em esquema fatorial (3x2x2), sendo três dietas, dois sexos e dois tempos de armazenamento (zero e 12 meses). Os parâmetros avaliados no peito e na coxa foram: pH final, cor (L* - luminosidade, a* - índice de vermelho, b* - índice de amarelo, C* - índice de saturação e h* - ângulo de tonalidade), perda de peso por cozimento (PPC), força de cisalhamento (FC) e estabilidade lipídica. Além disso, foram avaliadas a proporção das formas químicas da mioglobina da coxa e a quantificação do conteúdo de selênio no peito. Não houve efeito isolado da dieta sobre os parâmetros físicos e químicos do peito e da coxa e sobre a concentração de selênio no peito. As fêmeas apresentaram médias superiores de L* (57,57), b* (10,55) e C* (10,60) do peito; e os machos de L* (55,09) da coxa. Entre os machos, as aves alimentadas com a dieta controle e com cromo expressaram valores superiores de FC da coxa em relação às suplementadas com selênio; para o tratamento com cromo, os machos apresentaram média superior de FC da coxa e, em contrapartida, para o tratamento com selênio, as fêmeas manifestaram a maior média. As amostras submetidas ao período de 12 meses de armazenamento mostraram maiores valores de substâncias reativas ao ácido tiobarbitúrico (TBARS) em ambos os cortes. A suplementação com cromo e selênio biocomplexados não provocou alterações na qualidade da carne; as fêmeas demonstraram melhores atributos de qualidade da carne.(AU)


The objective of the present study was to evaluate the influence of the supplementation with biocomplexed minerals on the quality of the meat of label Rouge lineage chicken, of both genders, reared in an alternative system. The experimental design was completely randomized (CRD) in a factorial scheme (3x2), with three diets (control; 0.50ppm of selenium; 0.40ppm of chromium) and two genders. For lipid stability, the CRD arranged in a factorial scheme (3x2x2) was used, being three diets, two genders and two storage times (0 and 12 months). The parameters evaluated in the breast and in the thigh were: final pH, color (L* - luminosity, a* - red index, b* - yellow index, C* - saturation index and h* - tonality angle), weight loss per cooking (WLC), shear force (SF) and lipid stability. In addition, we evaluated the proportion of chemical forms of myoglobin of the thigh and the quantification of selenium content in the breast. There was no isolated effect of diet on the physical and chemical parameters of the breast and thigh and selenium concentration in the breast. Females had higher mean values of L* (57.57), b* (10.55) and C* (10.60) of the breast; and males of L* (55.09) of the thigh. Among males, poultry fed with the control diet and chromium showed higher SF values of the thigh than those supplemented with selenium; for the treatment with chromium, the males presented superior average of SF of the thigh and, in contrast, for the treatment with selenium, the females had the highest average. Samples submitted to the period of 12-month of storage showed higher values of substances reactive to thiobarbituric acid (TBARS) in both cuts. Supplementation with biocomplexed chromium and selenium did not cause changes in meat quality; females presented better attributes of meat quality.(AU)


Assuntos
Animais , Selênio/administração & dosagem , Galinhas/crescimento & desenvolvimento , Cromo/administração & dosagem , Carne/análise , Mioglobina , Suplementos Nutricionais/análise , Ração Animal/análise
13.
Rev. Assoc. Med. Bras. (1992, Impr.) ; Rev. Assoc. Med. Bras. (1992, Impr.);67(supl.1): 80-85, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1287842

RESUMO

SUMMARY OBJECTIVE: The present study compares the cardiac parameters of the survivor and nonsurvivor patients with COVID-19 infection. METHODS: This study was conducted in 379 patients diagnosed with COVID-19 disease. Information of 21 nonsurvivor and 358 survivor patients with COVID-19 was obtained from the hospital information management system and analyzed retrospectively. Relationship between cardiac parameters in patients categorized into the mortal and immortal groups was investigated. RESULTS: Of the total 379 patients involved in this study, 155 (40.9%) were females and 224 (59.1%) were males. No statistically significant difference in mortality was found between females and males (p=0.249). The total median age was 70, the median age in the nonsurvivor group was 74 (35-89), and it was 69.5 (18-96) in the survivor group (p=0.249). The median values of high-sensitivity troponin (hs-Tn), creatine kinase MB form, and especially myoglobin in the survivor and nonsurvivor groups were 25/64.9 (p=0.028), 18/23 (p=0.02), and 105.5/322.4 (p<0.001), and the difference was statistically significant. Comparing mortality, while there was 1 (0.7%) nonsurvivor out of 134 patients in the service unit, there were 20 (8.2%) nonsurvivors out of 245 patients in the intensive care unit. This difference was statistically significant (p=0.003). The cutoff value of myoglobin, which may pose a risk of mortality, was found to be 191.4 µg/L, while it was 45.7 ng/l for hs-Tn and 60.1 U/L for creatine kinase MB. CONCLUSIONS: Advanced age and increased levels of high-sensitivity troponin, creatine kinase MB, and myoglobin were found to be associated with mortality.


Assuntos
Humanos , Masculino , Feminino , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19 , Biomarcadores , Estudos Retrospectivos , Sobreviventes , Creatina Quinase , SARS-CoV-2 , Pessoa de Meia-Idade
14.
Elife ; 92020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32729830

RESUMO

High-altitude environments require that animals meet the metabolic O2 demands for locomotion and thermogenesis in O2-thin air, but the degree to which convergent metabolic changes have arisen across independent high-altitude lineages or the speed at which such changes arise is unclear. We examined seven high-altitude waterfowl that have inhabited the Andes (3812-4806 m elevation) over varying evolutionary time scales, to elucidate changes in biochemical pathways of energy metabolism in flight muscle relative to low-altitude sister taxa. Convergent changes across high-altitude taxa included increased hydroxyacyl-coA dehydrogenase and succinate dehydrogenase activities, decreased lactate dehydrogenase, pyruvate kinase, creatine kinase, and cytochrome c oxidase activities, and increased myoglobin content. ATP synthase activity increased in only the longest established high-altitude taxa, whereas hexokinase activity increased in only newly established taxa. Therefore, changes in pathways of lipid oxidation, glycolysis, and mitochondrial oxidative phosphorylation are common strategies to cope with high-altitude hypoxia, but some changes require longer evolutionary time to arise.


Assuntos
Anseriformes/metabolismo , Evolução Biológica , Metabolismo Energético , Músculo Esquelético/metabolismo , Altitude , Distribuição Animal , Animais , América do Sul
15.
Arch Biochem Biophys ; 687: 108391, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32360749

RESUMO

Hydropersulfides are reported to be good biological reductants, superior to thiols and akin to selenols. As such, they have been previously shown to reduce metalloproteins such as ferric myoglobin and ferric cytochrome c to their ferrous forms under conditions where little or no reduction from corresponding thiols is observed. Not surprisingly, the reduction of ferric myoglobin to ferrous myoglobin under aerobic conditions results in the generation of oxymyoglobin (dioxygen bound ferrous myoglobin). Previous studies have demonstrated that oxymyoglobin can also act as an oxidant with highly reducing species such as hydroxylamine and ascorbate. Considering the reducing properties of hydropersulfides, it is possible that they can also react with oxymyoglobin similarly to hydroxylamine or ascorbate. Herein, this reaction is examined and indeed hydropersulfides are found to react with oxymyoglobin similarly to other reducing species leading to a fleeting ferric myoglobin which is rapidly reduced to the ferrous form also by hydropersulfide.


Assuntos
Mioglobina/química , Sulfetos/química , Animais , Ácido Ascórbico/química , Bovinos , Cavalos , Hidroxilamina/química , Modelos Químicos , Oxirredução , Oxigênio/química , Penicilamina/análogos & derivados
16.
J Med Primatol ; 49(2): 65-70, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31885097

RESUMO

BACKGROUND: Non-human primates (NHPs) are susceptible to dogs' attacks, events that may cause muscle damage along with stress, and could be in some extent compatible with capture myopathy, a syndrome that results in myoglobinuria and renal damage. METHODS: We aimed to evaluate by histopathology pre-existing lesions and subsequent sequelae related to dogs' attacks, acute tubular necrosis (ATN) and myoglobinuria, as well as the usefulness of Pearls Stain and IHC to diagnose it. Histopathology was performed in available organs, and sections of kidney submitted to Prussian blue stain and myoglobin immunohistochemistry. RESULTS: During January 2014-June 2016, 16/145 (11%) of NHPs received by Adolfo Lutz Institute, Brazil were reported as attacked by dogs. A high frequency of young and debilitated animals was found. Myoglobinuria was observed in more than half animals (9/16; 56.2%), from which (5/9; 55.5%) presented ATN. CONCLUSIONS: Kidney lesions are plausible findings in NHPs attacked by dogs.


Assuntos
Alouatta , Mordeduras e Picadas/veterinária , Callithrix , Necrose Tubular Aguda/veterinária , Doenças dos Macacos/patologia , Mioglobinúria/veterinária , Fatores Etários , Animais , Mordeduras e Picadas/patologia , Mordeduras e Picadas/fisiopatologia , Brasil , Cães , Feminino , Rim/patologia , Necrose Tubular Aguda/diagnóstico , Necrose Tubular Aguda/patologia , Masculino , Doenças dos Macacos/diagnóstico , Mioglobinúria/diagnóstico , Mioglobinúria/patologia , Fatores Sexuais
17.
Ciênc. rural (Online) ; 50(11): e20200287, 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1133224

RESUMO

ABSTRACT: The aim of the present study was to compare the color and oxidative stability of light (LM) and dark (DM) muscles of Nile tilapia (Oreochromis niloticus) stored at 4 °C for eight days. Five different trials of LM and DM samples were analyzed for instrumental color attributes (lightness, redness and yellowness), including the surface color stability through ratio of reflectance at 630/580 nm (R630/580), myoglobin concentration, total lipid content, fatty acid profile, metmyoglobin reducing activity (MRA), pH, lipid oxidation and protein oxidation. Results of the present study indicated that DM of Nile tilapia (Oreochromis niloticus) present lower oxidative and color stability during refrigerated storage than LM.


RESUMO: O objetivo do presente estudo foi comparar a estabilidade de cor e oxidativa de músculos claros (LM) e escuros (DM) de tilápia do Nilo (Oreochromis niloticus) armazenados a 4° C por oito dias. Cinco repetições diferentes de amostras de LM e DM foram analisadas quanto aos atributos instrumentais de cor (luminosidade, teor de vermelho e teor de amarelo), incluindo a estabilidade de cor na superfície através da razão de refletâncias nos comprimentos de onda 630 e 580 nm (R630/580), concentração de mioglobina, lipídios totais, perfil de ácidos graxos, atividade de redução da metamioglobina (MRA), pH, oxidação lipídica e oxidação proteica. Os resultados do presente estudo indicam que músculos escuros (DM) de tilápia do Nilo (Oreochromis niloticus) apresentam menor estabilidade oxidativa e de cor durante o armazenamento refrigerado, quando comparados aos músculos claros (LM).

18.
Ci. Rural ; 50(11): e20200287, 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-29579

RESUMO

The aim of the present study was to compare the color and oxidative stability of light (LM) and dark (DM) muscles of Nile tilapia (Oreochromis niloticus) stored at 4 °C for eight days. Five different trials of LM and DM samples were analyzed for instrumental color attributes (lightness, redness and yellowness), including the surface color stability through ratio of reflectance at 630/580 nm (R630/580), myoglobin concentration, total lipid content, fatty acid profile, metmyoglobin reducing activity (MRA), pH, lipid oxidation and protein oxidation. Results of the present study indicated that DM of Nile tilapia (Oreochromis niloticus) present lower oxidative and color stability during refrigerated storage than LM.(AU)


O objetivo do presente estudo foi comparar a estabilidade de cor e oxidativa de músculos claros (LM) e escuros (DM) de tilápia do Nilo (Oreochromis niloticus) armazenados a 4° C por oito dias. Cinco repetições diferentes de amostras de LM e DM foram analisadas quanto aos atributos instrumentais de cor (luminosidade, teor de vermelho e teor de amarelo), incluindo a estabilidade de cor na superfície através da razão de refletâncias nos comprimentos de onda 630 e 580 nm (R630/580), concentração de mioglobina, lipídios totais, perfil de ácidos graxos, atividade de redução da metamioglobina (MRA), pH, oxidação lipídica e oxidação proteica. Os resultados do presente estudo indicam que músculos escuros (DM) de tilápia do Nilo (Oreochromis niloticus) apresentam menor estabilidade oxidativa e de cor durante o armazenamento refrigerado, quando comparados aos músculos claros (LM).(AU)


Assuntos
Animais , Ciclídeos/fisiologia , Oxidação , Músculos , Refrigeração
19.
Med. interna Méx ; 35(2): 191-197, mar.-abr. 2019. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1135166

RESUMO

Resumen OBJETIVO: Comparar la capacidad predictiva de mioglobina, creatincinasa total y hemoglobina en orina de lesión renal aguda en pacientes con traumatismo. MATERIAL Y MÉTODO: Estudio transversal, analítico, comparativo, observacional, en el que se identificaron todos los pacientes mayores de 18 años con diagnóstico de traumatismo o politraumatismo, provenientes del servicio de urgencias, de agosto de 2017 a enero de 2018 en el Hospital General Xoco de la Secretaría de Salud de la Ciudad de México, se midieron: mioglobina, creatincinasa total, concentraciones de creatinina y hemoglobina en orina a su ingreso. RESULTADOS: Se incluyeron 24 pacientes de 20 a 79 años de edad, con predominio del género masculino. Al comparar las áreas bajo la curva de las pruebas se determinó que no hubo significación estadística (p = 0.266) para la creatincinasa de ingreso porque mostró un área bajo la curva de 0.636, el intervalo de confianza al 95% se encontró por debajo de 0.500. Asimismo, la mioglobina de ingreso se observó en un área bajo la curva de 0.657 (p = 0.198; IC 95% 0.423-0.891). CONCLUSIONES: Las concentraciones de creatincinasa total y mioglobina no demostraron ser predictores adecuados de lesión renal al no haber diferencia significativa; sin embargo, se encontró que las concentraciones de creatinina al ingreso tienen mayor capacidad predictiva de lesión renal aguda en pacientes con traumatismo e hiperCKemia.


Abstract OBJECTIVE: To compare the predictive capacity of myoglobin, total creatine kinase and urine hemoglobin for acute renal injury in patients with trauma. MATERIAL AND METHOD: A cross-sectional, analytical, comparative, observational study was made with all adults over 18 years of age with a diagnosis of trauma or polytraumatism from August 2017 to January 2018 in the General Hospital of Xoco, Mexico City. Myoglobin, total creatine kinase, creatinine and hemoglobin levels were measured in urine at their admission. RESULTS: There were studied 24 patients from 20 to 79 years old, with a predominance of the male gender. When comparing the areas under the test curve it was determined that there was no statistical significance (p = 0.266) for the creatine kinase at the patient's admission, as it showed an area under the curve of 0.636, the 95% confidence interval was below 0.500. Likewise, the myoglobin at the patient's admission was observed under the curve area of 0.657 (p = 0.198; IC 95% 0.423-0.891). CONCLUSIONS: Levels of total creatine kinase and myoglobin did not prove to be adequate predictors of kidney injury because there was no significant difference. However, creatinine levels at admission have greater predictive capacity of acute renal injury in patients with trauma and hyperCKemia.

20.
Meat Sci ; 152: 20-30, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30798154

RESUMO

The effects of edible monolayer and bilayer chitosan-gelatin coatings on the weight loss, lipid oxidation, color preservation (display-life), and shelf-life of beef steaks during 10 days of retail display (at 4 °C; 12 h light/day) were evaluated. The edible coatings had a homogeneous crack-free surface, with the bilayer films being two times thicker than the monolayer coatings. During storage, the control samples had higher pH values and more weight loss (P < .05) than the coated ones. The coatings effectively retarded (P < .05) lipid oxidation and microbial growth (psychrotrophic bacteria, molds, and yeast), extending the shelf-life from 6 to 10 days. The coatings also significantly prevented metmyoglobin accumulation on the beef surface, as reflected in the maintenance of the CIE color indices and sensorial redness perception throughout storage. These effects were similar for both the monolayer and bilayer films, suggesting that chitosan-gelatin coatings could improve the shelf-life and display-life of beef during retail storage.


Assuntos
Quitosana , Embalagem de Alimentos/métodos , Gelatina , Carne Vermelha/normas , Animais , Bactérias/crescimento & desenvolvimento , Bovinos , Cor , Conservação de Alimentos/métodos , Fungos/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Peroxidação de Lipídeos , Metamioglobina/análise , Carne Vermelha/microbiologia
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