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1.
Sud Med Ekspert ; 62(4): 63-67, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31407710

RESUMO

A review of the techniques used by Nizhny Novgorod forensic physicians in studying the possibility of using biochemical methods in expert practice is presented. Changes at the molecular level in pathological conditions precede functional and morphological disorders in tissues and organs. The use of biochemical methods - in particular, the study of the concentration of myoglobin and substances of low and medium molecular weight - significantly expands the possibilities of forensic-medical ekspertise. The authors study investigated the effect of the sampling period and the storage conditions of biomaterial on the results of biochemical studies; the dynamics of myoglobin content in determining whether a victim was dead or alive at the time of injury, and how long ago the injury occurred; and the nature of ischemic myocardial damage. The possibility of using substances of low and medium molecular weight in determining the cause of death was evaluated.


Assuntos
Causas de Morte , Medicina Legal/métodos , Mioglobina/análise , Projetos de Pesquisa , Humanos , Manejo de Espécimes
2.
Talanta ; 202: 111-122, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31171159

RESUMO

A new dual-modality immunosensor based on molecularly imprinted polymer (MIP) and a nanostructured biosensing layer has fabricated for the simultaneous detection of two important markers including prostate-specific antigen (PSA) and myoglobin (Myo) in human serum and urine samples. In the first step, 3,3'-dithiodipropionic acid di(N-hydroxysuccinimide ester) (DSP) was self-assembled on a gold screen printed electrode (SPE). Then, the target proteins were attached covalently to the DSP-SPE. The imprinted cocktail polymer ((MIP(PSA, Myo)-SPE)) was synthesized at the SPE surface using acrylamide as monomer, N,N'-methylenebisacrylamide as a crosslinker, and PSA and Myo as the templates, respectively. The MIP-SPE was specific for the impedimetric sensing of PSA and Myo. After that, a nanocomposite (NCP) was synthesized based on the decorated magnetite nanoparticles with multi-walled carbon nanotube, graphene oxide and specific antibody for PSA (Ab). Then, NCP incubated with (MIP(PSA, Myo)-SPE. The modified electrodes and synthesized nanoparticles were characterized using electrochemical impedance spectroscopy, dynamic light scattering, surface plasmon resonance and scanning electron microscopy. The limits of detections were found to be 5.4 pg mL-1 and 0.83 ng mL-1 with the linear dynamic ranges of 0.01-100 and 1-20000 ng mL-1 for PSA and Myo, respectively. The ability of proposed biosensor to detect PSA and Myo simultaneously with high sensitivity and specificity offers a powerful opportunity for the new generation of biosensors. This dual-analyte specific receptors-based device is highly desired for the integration with lab-on-chip kits to measure a wide panel of biomarkers present at ultralow levels during early stages of diseases progress.


Assuntos
Biomarcadores Tumorais/análise , Técnicas Biossensoriais , Técnicas Eletroquímicas , Mioglobina/análise , Polímeros/química , Antígeno Prostático Específico/análise , Neoplasias da Próstata/diagnóstico , Anticorpos/imunologia , Reações Antígeno-Anticorpo , Biomarcadores Tumorais/imunologia , Eletrodos , Humanos , Masculino , Impressão Molecular , Mioglobina/imunologia , Nanopartículas/química , Antígeno Prostático Específico/imunologia , Neoplasias da Próstata/imunologia
3.
Food Chem ; 275: 369-376, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30724209

RESUMO

The potential of diffuse reflectance spectroscopy (DRS) to quantify the met-myoglobin (met-Mb) proportion and meat oxygenation inside of pork and beef was examined. First, reflection spectra were obtained from pork (n = 52) and beef (n = 43) samples under fresh and stored conditions. Second, the DRS algorithm was applied to the reflectance spectra to calculate the met-Mb proportion and oxygenation of the meat. Lastly, a regression model was developed showing the change in the met-Mb proportion and oxygenation during met-Mb formation and degradation. A linear relationship existed between the DRS-based computed data and the known met-Mb proportion with a high correlation (R2 = 0.9999) and a low error (0.86%). Measurement of the meat samples revealed a linear increment of the met-Mb proportion (R2 = 0.77) and a quadratic change in the oxygenation (R2 = 0.44) during the met-Mb formation process. This study demonstrated the ability of DRS to quantitatively analyze the relative content of myoglobin derivatives in both pork and beef.


Assuntos
Análise de Alimentos/métodos , Mioglobina/análise , Carne Vermelha/análise , Análise Espectral/métodos , Animais , Bovinos , Armazenamento de Alimentos , Oxigênio/química , Suínos
4.
Food Chem ; 283: 646-655, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30722923

RESUMO

The effects of a hydroxyl radical generating system (Fe3+/H2O2) at different H2O2 concentrations (0, 1 and 10 mM) on the chemical and structural properties of isoelectric solubilization/precipitation (ISP)-isolated PSE (pale, soft, exudative)-like chicken protein were investigated. Both acid and alkaline treatments effectively reduced the pro-oxidant contents in PSE-like meat systems, such as lipids, pigments and myoglobins. The ISP samples generated less carbonyl derivatives and Schiff base but yielded higher sulfhydryl and free amine loss in response to oxidation. Correspondingly, sulfur-contained amino acids in ISP samples were more easily converted, even at the 1-mM H2O2 concentration, than in the PSE-like meat paste. Moreover, the ISP-isolated proteins have possibly maintained their gelling properties after oxidation compared to the PSE-like meat paste. In regards to chemical and structural modification, the ISP treated protein showed a different susceptibility to oxidation in vitro.


Assuntos
Galinhas/metabolismo , Radical Hidroxila/química , Proteínas Musculares/química , Animais , Precipitação Química , Eletroforese em Gel de Poliacrilamida , Peróxido de Hidrogênio/química , Ponto Isoelétrico , Lipídeos/análise , Carne/análise , Proteínas Musculares/isolamento & purificação , Proteínas Musculares/metabolismo , Mioglobina/análise , Oxirredução , Carbonilação Proteica , Compostos de Sulfidrila/análise
5.
J Emerg Med ; 56(4): 386-397, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30685220

RESUMO

BACKGROUND: Acute compartment syndrome (ACS) is a time-sensitive surgical emergency caused by increased pressure within a closed compartment. ACS can lead to significant morbidity and mortality if it is not rapidly identified and treated. OBJECTIVE: This article provides an evidence-based review of the diagnosis and management of ACS, with focused updates for the emergency clinician. DISCUSSION: ACS is the result of decreased perfusion within a compartment and is associated with a number of risk factors, but it occurs most commonly after fractures or trauma to the involved area. It can present with a variety of findings, including pain out of proportion to the injury, paresthesias, pain with passive stretch, tenseness or firmness of the compartment, focal motor or sensory deficits, or decreased pulse or capillary refill time. Pain is typically the earliest finding in patients with ACS. Unfortunately, history and physical examination are typically unreliable and cannot rule out the diagnosis. Measurement of intracompartmental pressures using a pressure monitor is the most reliable test, though noninvasive means of diagnosis are under study. Treatment involves surgical consultation for emergent fasciotomy, as well as resuscitation and management of complications, such as rhabdomyolysis. CONCLUSION: ACS is a dangerous medical condition requiring rapid diagnosis and management that can result in significant complications if not appropriately diagnosed and treated. Emergency clinician awareness and knowledge of this condition is vital to appropriate management.


Assuntos
Síndromes Compartimentais/diagnóstico , Síndromes Compartimentais/terapia , Doença Aguda/terapia , Adulto , Síndromes Compartimentais/fisiopatologia , Creatina Quinase/análise , Creatina Quinase/sangue , Serviço Hospitalar de Emergência/organização & administração , Prática Clínica Baseada em Evidências/métodos , Fasciotomia/métodos , Feminino , Humanos , Perna (Membro)/anatomia & histologia , Masculino , Mioglobina/análise
6.
Anal Sci ; 34(12): 1393-1399, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30531104

RESUMO

Adsorption of protein molecules into the pores of a porous material is an important process for chromatographic separation of proteins and synthesis of nanoscale biocatalyst systems; however, there are barriers to developing a method for analyzing the process quantitatively. The purpose of this study is to examine the applicability of differential scanning calorimetry (DSC) for quantitative analysis of protein adsorption into silica mesopores. For this purpose myoglobin, a globular protein (diameter: 35.2 Å) was selected, and its adsorption onto mesoporous silica powders with uniform pore diameters (pore diameters: 39 and 64 Å) was measured by adsorption assay and DSC experiments. Our results confirmed that the adsorption of myoglobin into the silica mesopores induced significant changes in the positions and areas of freezing/melting peaks of the pore water. The decrease in heat of fusion of the pore water after myoglobin adsorption could be utilized to quantify the amount of myoglobin inside the silica mesopores. The advantages of DSC include its applicability to small wet mesoporous silica samples.


Assuntos
Varredura Diferencial de Calorimetria/métodos , Mioglobina/análise , Dióxido de Silício/química , Adsorção , Animais , Tamanho da Partícula , Porosidade , Solubilidade , Propriedades de Superfície
7.
Forensic Sci Med Pathol ; 14(3): 358-366, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29956100

RESUMO

Conducted Electrical Weapons (CEWs) are being used as the preferred non-lethal force option for police and special forces worldwide. This new technology challenges an exposed opponent similarly to the way they would be challenged by physical exercise combined with emotional stress. While adrenergic and metabolic effects have been meta-analyzed and reviewed, there has been no systematic review of the effects of CEWs on skeletal and cardiac muscle. A systematic and careful search of the MedLine database was performed to find publications describing pathophysiological cardiac and skeletal muscle effects of CEWs. For skeletal muscle effects, we analyzed all publications providing changes in creatine kinase, myoglobin and potassium. For cardiac effects, we analyzed reported troponin changes and arrhythmias related to short dart-to-heart-distances. Conducted electrical weapons satisfy all relevant electrical safety standards and there are, to date, no proven electrocution incidents caused by CEWs. A potential cardiovascular risk has been recognized by some of the experimental animal data. The effects on the heart appear to be limited to instances when there is a short dart-to-heart-distance. The effect on the skeletal muscle system appears to be negligible. A responsible use of a CEW on a healthy adult, within the guidelines proposed by the manufacturer, does not imply a significant health risk for that healthy adult.


Assuntos
Lesões por Armas de Eletrochoque , Animais , Creatina Quinase/análise , Desfibriladores Implantáveis , Humanos , Contração Muscular , Mioglobina/análise , Marca-Passo Artificial , Troponina/sangue , Fibrilação Ventricular/etiologia
8.
Molecules ; 23(5)2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29693580

RESUMO

The study evaluated the effect of pig diet supplementation with rapeseed or linseed oil, and vitamin E or selenium, or both vitamin E and selenium on color parameters and myoglobin content of pork Semimembranosus muscle after long-term freezing storage during nine months. The influence of the type of the bioactive compounds added to pig diet on the content of myoglobin or oxymyoglobin, metmyoglobin and deoksymyoglobin in Semimembranosus m. was also assessed. The results indicate that the presence of oils rich in polyunsaturated fatty acids (PUFA) in pig diet improves the color of pork meat. Supplementation of dietary plant oils or dietary oils with antioxidants tended to increase significantly the concentration of oxymyoglobin and decrease the concentration of metmyoglobin in meat compared to the control group. The highest content of oxymyoglobin was observed in meat obtained from pigs fed diets with linseed oil. The best color scores (highest a* parameter) was noted for rapeseed oil group (with no addition of antioxidants). In conclusion, the addition of antioxidants to pigs’ forage supplemented with PUFA-rich oils is not recommended in order to improve color of long-term frozen pork.


Assuntos
Ácidos Graxos Insaturados/administração & dosagem , Mioglobina/análise , Óleos Vegetais/química , Carne Vermelha/análise , Selênio/administração & dosagem , Vitamina E/administração & dosagem , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais , Ácidos Graxos Insaturados/farmacologia , Óleo de Semente do Linho/química , Óleo de Brassica napus/química , Refrigeração , Selênio/farmacologia , Suínos , Vitamina E/farmacologia
9.
J Sci Food Agric ; 98(13): 5120-5128, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29635816

RESUMO

BACKGROUND: Meat from birds is a rich source of proteins for the human diet. In this framework, Eurasian woodcock (Scolopax rusticola L.), a medium-small wading bird hunted as game in many Eurasian countries, is considered one of the best meats for culinary purposes. Since the nutritional composition of Eurasian woodcock meat has not yet been reported, we decided to determine the nutritional profile of S. rusticola meat. RESULTS: Macronutrient components (proteins, lipids and fatty acids) were determined, as well as free and total amino acids, and compared with those of the common pheasant. Eurasian woodcock meat contains high levels of proteins and essential amino acids. The levels of unsaturated fatty acids represent a great contribution to the total lipid amount. Among polyunsaturated fatty acids, linoleic acid (C18:2, n-6) is the major essential fatty acid. Finally, we report the characterization of myoglobin (Mb) from Eurasian woodcock. CONCLUSION: The data revealed that meat from this bird could be a good source of quality raw proteins because of its amino acid composition, and it had a low lipid content. On the other hand, Mb characterization might be of benefit to the meat industry, by providing useful information for the determination of species-specific differences in meat from birds. © 2018 Society of Chemical Industry.


Assuntos
Charadriiformes , Carne/análise , Mioglobina/análise , Aminoácidos/análise , Animais , Ácidos Graxos/análise , Valor Nutritivo
10.
BMC Complement Altern Med ; 18(1): 13, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29334926

RESUMO

BACKGROUND: Fructose-mediated protein glycation (fructation) has been linked to an increase in diabetic and cardiovascular complications due to over consumption of high-fructose containing diets in recent times. The objective of the present study is to evaluate the protective effect of (R)-α-lipoic acid (ALA) against fructose-induced myoglobin fructation and the formation of advanced glycation end products (AGEs) in vitro. METHODS: The anti-glycation activity of ALA was determined using the formation of AGEs fluorescence intensity, iron released from the heme moiety of myoglobin and the level of fructosamine. The fructation-induced myoglobin oxidation was examined using the level of protein carbonyl content and thiol group estimation. RESULTS: The results showed that co-incubation of myoglobin (1 mg/mL), fructose (1 M) and ALA (1, 2 and 4 mM) significantly inhibited the formation of AGEs during the 30 day study period. ALA markedly decreased the levels of fructosamine, which is directly associated with the reduction of AGEs formation. Furthermore, ALA significantly reduced free iron release from myoglobin which is attributed to the protection of myoglobin from fructose-induced glycation. The results also demonstrated a significant protective effect of ALA on myoglobin oxidative damages, as seen from decreased protein carbonyl content and increased protein thiols. CONCLUSION: These findings provide new insights into the anti-glycation properties of ALA and emphasize that ALA supplementation is beneficial in the prevention of AGEs-mediated diabetic and cardiovascular complications.


Assuntos
Frutose/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Glicosilação/efeitos dos fármacos , Mioglobina/metabolismo , Ácido Tióctico/farmacologia , Animais , Produtos Finais de Glicação Avançada/análise , Mioglobina/análise , Mioglobina/química
11.
Anal Chim Acta ; 1004: 51-57, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29329708

RESUMO

Detection of native proteins, particularly directly from raw biological samples, has been a challenging task for mass spectrometry. In this study, we demonstrated that solid-substrate electrospray ionization mass spectrometry with nonpolar solvents such as n-hexane could allow detection of native proteins and protein complexes directly from raw biological samples. Mechanistic study revealed that the process involved rapid vaporization of the nonpolar solvent, temperature reduction of substrate surface, condensation of water from the ambient air, and spray ionization of the condensed water with analytes under the electric field. The fine spray with water at low temperature allowed the technique to detect native proteins, even directly from viscous samples (e.g., egg white) and solid samples (e.g., bone marrow). This study sheds new insight into the sampling and ionization process of mass spectrometry and provides a technique of great potential for characterization of proteins.


Assuntos
Hexanos/química , Muramidase/análise , Mioglobina/análise , Muramidase/metabolismo , Solventes/química , Espectrometria de Massas por Ionização por Electrospray , Volatilização , Água/química
12.
J Proteome Res ; 17(2): 926-933, 2018 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-29249155

RESUMO

As the application of mass spectrometry intensifies in scope and diversity, the need for advanced instrumentation addressing a wide variety of analytical needs also increases. To this end, many modern, top-end mass spectrometers are designed or modified to include a wider range of fragmentation technologies, for example, ECD, ETD, EThcD, and UVPD. Still, the majority of instrument platforms are limited to more conventional methods, such as CID and HCD. While these latter methods have performed well, the less conventional fragmentation methods have been shown to lead to increased information in many applications including middle-down proteomics, top-down proteomics, glycoproteomics, and disulfide bond mapping. We describe the modification of the popular Q Exactive Orbitrap mass spectrometer to extend its fragmentation capabilities to include ECD. We show that this modification allows ≥85% matched ion intensity to originate from ECD fragment ion types as well as provides high sequence coverage (≥60%) of intact proteins and high fragment identification rates with ∼70% of ion signals matched. Finally, the ECD implementation promotes selective disulfide bond dissociation, facilitating the identification of disulfide-linked peptide conjugates. Collectively, this modification extends the capabilities of the Q Exactive Orbitrap mass spectrometer to a range of new applications.


Assuntos
Elétrons , Fragmentos de Peptídeos/análise , Processamento de Proteína Pós-Traducional , Proteômica/instrumentação , Espectrometria de Massas em Tandem/instrumentação , Sequência de Aminoácidos , Dissulfetos/química , Desenho de Equipamento , Humanos , Íons , Mioglobina/análise , Mioglobina/química , Fragmentos de Peptídeos/química , Proteólise , Proteômica/métodos , Substância P/análise , Substância P/química , Espectrometria de Massas em Tandem/métodos , Ubiquitina/análise , Ubiquitina/química
13.
Nefrologia ; 38(2): 161-168, 2018 Mar - Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29198593

RESUMO

BACKGROUND: Online haemodiafiltration (OL-HDF) is currently the most effective dialysis technique that also improves survival. To date, high permeability membranes with low albumin loss, such as polysulfone, polyamide and polyacrylonitrile membranes have been the most widely used. However, the initially restricted use of cellulose triacetate (CTA) membranes in OL-HDF has expanded. The aim of the study was to ascertain whether the latest generation asymmetric CTA membranes are more effective in obtaining high convective transport. PATIENTS AND METHODS: A total of 16 patients (10 males and 6 females) undergoing OL-HDF were studied. Each patient underwent 4 different sessions, with haemodialysis or OL-HDF, and/or with CTA or asymmetric CTA 1.9 m2 membranes. Each session was assigned in a randomised order. Serum levels of urea, creatinine, ß2-microglobulin, myoglobin, prolactin, α1-microglobulin, α1-acid glycoprotein and albumin where measured at the beginning and end of each session to obtain the reduction rate. The loss of solutes and albumin was quantified from the dialysate. RESULTS: A significantly greater replacement volume in OL-HDF (32.1±3.1 vs. 19.7±4.5 l, P<.001) was obtained by using asymmetrical CTA membranes compared to conventional CTA membranes. Regarding uraemic toxin removal, both membranes obtained similar results for small molecules, whereas asymmetric CTA membranes achieved better results for large molecules, increasing the reduction ratio by 29% for ß2-microglobulin, 27.7% for myoglobin, 19.5% for prolactin, 49% for α1-microglobulin and double for α1-acid glycoprotein (P<0.001 in all situations). The loss of albumin was less than 2g for all treatment sessions. CONCLUSION: Latest-generation asymmetric CTA have proven to be effective in attaining OL-HDF objectives without increased albumin loss.


Assuntos
Celulose/análogos & derivados , Hemodiafiltração/instrumentação , Falência Renal Crônica/terapia , Membranas Artificiais , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Creatinina/análise , Desenho de Equipamento , Feminino , Hemodiafiltração/métodos , Soluções para Hemodiálise/química , Humanos , Falência Renal Crônica/sangue , Masculino , Pessoa de Meia-Idade , Mioglobina/análise , Orosomucoide/análise , Prolactina/análise , Diálise Renal/instrumentação , Toxinas Biológicas/análise , Microglobulina beta-2/análise
14.
Meat Sci ; 136: 50-58, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29096287

RESUMO

The bulk optical properties (BOP) of two bovine muscles were studied in the 500nm to 1850nm wavelength range. Over a two-week period of wet aging, the BOP of the biceps femoris (BF) and longissimus lumborum (LL) were determined and related to moisture content, tenderness and cooking loss. The absorption by myoglobin and reduced scattering coefficient were higher in the BF compared to the LL. The scattering anisotropy factor was relatively high (>0.95 for LL), representing dominant forward scattering. Two-toning effects in the BF could be attributed to significant scattering differences, as no differences in absorption properties were observed. During wet aging, the anisotropy factor decreased, while tenderness increased. It was hypothesized that this might be related to proteolysis of cytoskeletal proteins. The results show the potential use of BOP to monitor tenderization and the cause of color differences in beef muscles. Moreover, this information could be used to develop and optimize optical sensors for non-destructive meat quality monitoring.


Assuntos
Músculo Esquelético/metabolismo , Fenômenos Ópticos , Carne Vermelha/análise , Animais , Bovinos , Cor , Culinária , Manipulação de Alimentos/métodos , Masculino , Mioglobina/análise , Fatores de Tempo
15.
Eur J Pharm Biopharm ; 126: 101-103, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29054386

RESUMO

In this research note, interlaced Size Exclusion Chromatography (SEC) is used to shorten the duration of protein analysis. The applied method has a threefold higher sample throughput than comparable ones using conventional SEC. Further important advantages are the identical area's precision and the preservation of protein stability. Two different applications are presented where a short time interval of analysis is very important. One application is the determination of aggregates of monoclonal antibodies (mAbs). A high number of antibody samples have to be analyzed during the development process. The antibody sample was measured in a series of 60 injections within only 5.5 h instead of 16 h. The second application is the two-dimensional (2 D) separation of protein mixtures. The number of samples typically increases from the first to the second dimension. Thus, interlaced SEC is a reasonable option for the second dimension. This work confirms the functionality of interlaced SEC and widens the applicable range. Interlaced SEC can become a convenient option for method acceleration in the future.


Assuntos
Cromatografia em Gel/métodos , Proteínas/análise , Animais , Anticorpos Monoclonais/análise , Bovinos , Mioglobina/análise , Ovalbumina/análise , Soroalbumina Bovina/análise , Fatores de Tempo
16.
Meat Sci ; 135: 54-61, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28898754

RESUMO

Astaxanthin is proven to be one of the most potent, naturally occurring antioxidants. A rich source of astaxanthin is algae Haematoccocus pluvialis (H. pluvialis). The aim of the study was to investigate antioxidant effect of H. pluvalis extract added in different levels (0.15, 0.3 or 0.45g/kg of meat) on colour and oxidative stability of raw ground pork meat during refrigerated storage (7days). Obtained data revealed that DPPH scavenging activity of the extract at the concentration of 0.45g/kg of meat was as high as 85%. Moreover, application of higher extract doses (0.3 and 0.45g/kg) delayed lipids oxidation (lower TBARS value than control) and improved colour stability (increased a* colour parameter). Additionally, usage of 0.3 and 0.45g/kg had a positive effect on meat acceptance declared by consumers' at the final day of storage. However, the extract of H. pluvialis had no antimicrobial or antioxidative activity against myoglobin oxidation.


Assuntos
Clorófitas/química , Armazenamento de Alimentos , Carne Vermelha/análise , Animais , Antioxidantes/química , Cor , Feminino , Microbiologia de Alimentos , Humanos , Masculino , Músculo Esquelético/metabolismo , Mioglobina/análise , Oxirredução , Extratos Vegetais/química , Refrigeração , Suínos , Xantofilas/química
17.
J Sci Food Agric ; 98(4): 1346-1361, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28782814

RESUMO

BACKGROUND: Following public concern on the use of synthetic food antioxidants, there is an increasing demand for the application of mixed or purified natural antioxidants to maintain quality of meat products quality during storage. The aim of this research was to investigate the effect of ethanolic extract of hawthorn berry, compared to butylated hydroxylanisole (BHA), on lipid peroxidation, myoglobin oxidation, protein electrophoresis pattern, consistency and firmness of minced pork during refrigeration at 4 °C, and to identify the relationship between chemical modifications and consistency variation. RESULTS: After 6 days of refrigeration it was found that the thiobarbituric acid reactive substances value of minced pork containing 200 mg GAE kg-1 total phenolics in minced meat (200 HP) was significantly lower (0.1543 ± 0.006 mg) compared to BHA-treated meat. The ratio of oxymyoglobin to metmyoglobin in treated minced pork was respectively 0.845 for 200 HP and 0.473 for BHA-treated minced meat. Concentrations of 100 HP or 300 HP will generate statistically higher firmness than BHA in minced pork. CONCLUSION: Hawthorn berry ethanolic extract was more effective than BHA in reducing lipid oxidation and protein degradation, for maintaining firmness and consistency of minced pork during 6 days of refrigeration at 4 °C. © 2017 Society of Chemical Industry.


Assuntos
Hidroxianisol Butilado/farmacologia , Crataegus/química , Frutas/química , Produtos da Carne/análise , Extratos Vegetais/farmacologia , Suínos , Animais , Etanol , Conservação de Alimentos/métodos , Peroxidação de Lipídeos/efeitos dos fármacos , Metamioglobina/análise , Mioglobina/análise , Mioglobina/química , Mioglobina/efeitos dos fármacos , Oxirredução , Fenóis/farmacologia , Refrigeração , Substâncias Reativas com Ácido Tiobarbitúrico/análise
18.
Meat Sci ; 136: 23-29, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29059539

RESUMO

The experiment studied the effects of rosemary distillation residues (RR) intake on lamb meat quality, oxidative stability and fatty acid (FA) profile. Barbarine lambs of Control group were fed 600g of hay, which was substituted by 600g of pellets containing 60 and 87% of RR for RR60 and RR87 groups; all animals received 600g of concentrate. Meat protein and fat content was similar for 3 treatments. Lipid oxidation was strongly reduced with RR diets. Both RR diets resulted in a higher α- tocopherol content in muscle. The metmyoglobin and deoxymyoglobin percentages were similar for all groups; however oxymyoglobin was higher for RR groups. The saturated (SFA) and unsaturated FAs (UFA) were unaffected by the diets. However, the PUFA, n-6 and n-3 were higher for RR groups. In conclusion, rosemary residues resulted in higher vitamin E content, so it enhanced the oxidative status and improved the fatty acid profile of lamb meat.


Assuntos
Dieta/veterinária , Ácidos Graxos/análise , Carne Vermelha/análise , Rosmarinus , alfa-Tocoferol/análise , Ração Animal/análise , Animais , Metabolismo dos Lipídeos , Músculo Esquelético/química , Mioglobina/análise , Oxirredução , Carneiro Doméstico
19.
Chem Commun (Camb) ; 53(86): 11774-11777, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-29034393

RESUMO

This paper describes a centrifugal micropipette-tip method for ELISA sample processing combined with a pressure meter for portable quantitative detection of acute myocardial infarction (AMI) biomarker myoglobin (Myo). The method enables sensitive and reliable quantification of Myo in 35 minutes. With the advantages of simplicity, speed, user friendliness, low cost, and small sample consumption, centrifugal micropipette-tip ELISA shows great potential for quantitative POC diagnostics for AMI.


Assuntos
Centrifugação/instrumentação , Ensaio de Imunoadsorção Enzimática/instrumentação , Mioglobina/análise , Pressão , Biomarcadores/análise , Centrifugação/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Infarto do Miocárdio/diagnóstico
20.
Anal Chim Acta ; 981: 41-52, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28693728

RESUMO

An electrochemical biosensor was developed by merging the features of Molecular Imprinting technique and Screen-Printed Electrode (SPE) for the simple and fast screening of cardiac biomarker myoglobin (Myo) in point-of-care (POC). The MIP artificial receptor for Myo was prepared by electrooxidative polymerization of phenol (Ph) on a AuSPE in the presence of Myo as template molecule. The choice of the most effective protein extraction procedure from the various extraction methods tested (mildly acidic/basic solutions, pure/mixed organic solvents, solutions containing surfactants and enzymatic digestion methods), and the optimization of the thickness of the polymer film was carefully undertaken in order to improve binding characteristics of Myo to the imprinted polymer receptor and increase the sensitivity of the MIP biosensor. The film thickness was optimized by adjusting scan rate and the number of cycles during cyclic voltammetric electropolymerization of Ph. The thickness of the polyphenol nanocoating of only few nanometres (∼4.4 nm), and similar to the protein diameter, brought in significant improvements in terms of sensor sensitivity. The binding affinity of MIP receptor film was estimated by fitting the experimental data to Freundlich isotherm and a ∼8 fold increase in the binding affinity of Myo to the imprinted polymer (KF = 0.119 ± 0.002 ng-1 mL) when compared to the non-imprinted polymer (KF = 0.015 ± 0.002 ng-1 mL) which demonstrated excellent (re)binding affinity for the imprinted protein. The incubation of the Myo MIP receptor modified electrode with increasing concentration of protein (from 0.001 ng mL-1 to 100 µg mL-1) resulted in a decrease of the ferro/ferricyanide redox current. LODs of 2.1 and 14 pg mL-1 were obtained from calibration curves built in neutral buffer and diluted artificial serum, respectively, using SWV technique, enabling the detection of the protein biomarker at clinically relevant levels. The prepared MIP biosensor was applied to the determination of Myo spiked serum samples with satisfactory results.


Assuntos
Impressão Molecular , Mioglobina/análise , Polifenóis/química , Animais , Biomarcadores/análise , Eletrodos , Mioglobina/sangue , Polimerização , Polímeros
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