Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.500
Filtrar
1.
Aging (Albany NY) ; 12(15): 15730-15740, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32805730

RESUMO

BACKGROUND: SARS-CoV-2 has raged around the world since March, 2020. We aim to describe the clinical characteristics and risk factors of severe patients with COVID-19 in Guangzhou. RESULTS: The severity and mortality of COVID-19 was 10.4% and 0.3% respectively. And each 1-year increase in age (OR, 1.057; 95% CI, 1.018-1.098; P=0.004), Wuhan exposure history greater than 2 weeks (OR, 2.765; 95% CI, 1.040-7.355; P=0.042), diarrhea (OR, 24.349; 95% CI, 3.580-165.609; P=0.001), chronic kidney disease (OR, 6.966; 95% CI, 1.310-37.058; P = 0.023), myoglobin higher than 106 µg/L (OR, 8.910; 95% CI, 1.225-64.816; P=0.031), white blood cell higher than 10×109/L (OR, 5.776; 95% CI, 1.052-31.722; P=0.044), and C-reactive protein higher than 10 mg/L (OR, 5.362; 95% CI, 1.631-17.626; P=0.006) were risk factors for severe cases. CONCLUSION: Older age, Wuhan exposure history, diarrhea, chronic kidney disease, elevated myoglobin, elevated white blood cell and C-reactive protein were independent risk factors for severe patients with COVID-19 in Guangzhou. METHODS: We included 288 adult patients with COVID-19 and compared the data between severe and non-severe group. We used univariate and multivariate logistic regression methods to explore risk factors of severe cases.


Assuntos
Proteína C-Reativa/análise , Infecções por Coronavirus , Diarreia , Contagem de Leucócitos/métodos , Mioglobina/análise , Pandemias , Pneumonia Viral , Insuficiência Renal Crônica/epidemiologia , Fatores Etários , Betacoronavirus/isolamento & purificação , China/epidemiologia , Infecções por Coronavirus/sangue , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/fisiopatologia , Diarreia/diagnóstico , Diarreia/etiologia , Feminino , Humanos , Período de Incubação de Doenças Infecciosas , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/sangue , Pneumonia Viral/diagnóstico , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/etiologia , Pneumonia Viral/mortalidade , Pneumonia Viral/fisiopatologia , Fatores de Risco , Índice de Gravidade de Doença
2.
Artigo em Inglês | MEDLINE | ID: mdl-32582575

RESUMO

Background: A novel enveloped RNA beta coronavirus, Corona Virus Disease 2019 (COVID-19) caused severe and even fetal pneumonia in China and other countries from December 2019. Early detection of severe patients with COVID-19 is of great significance to shorten the disease course and reduce mortality. Methods: We assembled a retrospective cohort of 80 patients (including 56 mild and 24 severe) with COVID-19 infection treated at Beijing You'an Hospital. We used univariable and multivariable logistic regression analyses to select the risk factors of severe and even fetal pneumonia and build scoring system for prediction, which was validated later on in a group of 22 COVID-19 patients. Results: Age, white blood cell count, neutrophil, glomerular filtration rate, and myoglobin were selected by multivariate analysis as candidates of scoring system for prediction of disease severity in COVID-19. The scoring system was applied to calculate the predictive value and found that the percentage of ICU admission (20%, 6/30) and ventilation (16.7%, 5/30) in patients with high risk was much higher than those (2%, 1/50; 2%, 1/50) in patients with low risk (p = 0.009; p = 0.026). The AUC of scoring system was 0.906, sensitivity of prediction is 70.8%, and the specificity is 89.3%. According to scoring system, the probability of patients in high risk group developing severe disease was 20.24 times than that in low risk group. Conclusions: The possibility of severity in COVID-19 infection predicted by scoring system could help patients to receiving different therapy strategies at a very early stage. Topic: COVID-19, severe and fetal pneumonia, logistic regression, scoring system, prediction.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/patologia , Pneumonia Viral/epidemiologia , Pneumonia Viral/patologia , Índice de Gravidade de Doença , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus/patogenicidade , China , Comorbidade , Progressão da Doença , Feminino , Taxa de Filtração Glomerular/fisiologia , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Mioglobina/análise , Infiltração de Neutrófilos/imunologia , Neutrófilos/imunologia , Pandemias , Prognóstico , Estudos Retrospectivos
3.
J Anim Sci ; 98(4)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32157294

RESUMO

The objective of this study was to determine the impact of quality grade and steak location on color stability of semitendinosus (ST) steaks during a 9-d refrigerated study. Twenty-one ST muscles (12 Choice and 9 Select) were purchased from a commercial beef packing plant and fabricated into twelve 2.54-cm thick steaks per muscle. Steaks 1, 6, and 12 were designated for immunohistochemistry while remaining steak locations of proximal (steaks 2 to 4), middle (5 to 8), and distal (9 to 11) were randomly assigned to 0, 4, or 9 d of simulated retail display. Surface color attributes of day-9 steaks were recorded daily by a visual color panel and spectrophotometer. On days 0, 4, and 9 of display, steaks were analyzed for metmyoglobin reducing ability (MRA) and oxygen consumption (OC). Grade × day of display (DOD) interactions were detected for L*, a*, surface oxymyoglobin (OMb) and metmyoglobin (MMb) percentages, and visual panel surface redness and discoloration scores (P ≤ 0.02); however, no Grade × DOD interactions were observed for MRA or OC (P > 0.17). There were location main effect (LOC) × DOD interactions for L*, a*, surface MMb, visual panel surface redness and discoloration, and MRA (P ≤ 0.02). Distal steaks had lower L* values compared with the other locations (P < 0.01), which coincided with steaks being rated visually darker red (P < 0.01). Proximal steaks had greater a* values and had less surface discoloration than middle steaks (P < 0.05), which had an increased percentage of surface MMb (P ≤ 0.04). Distal and proximal steaks had increased MRA compared with middle steaks on days 0 and 4 (P < 0.05), and distal steaks had greater OC than the other locations throughout display (P < 0.01). There were fewer type I fibers at the proximal end with a greater percentage located at the middle and distal ends, and an increased percentage of type IIX fibers at the middle and proximal locations (P ≤ 0.01). Less type IIA fibers were detected at the middle LOC compared with the other two locations (P < 0.10). Larger type I, IIA, and IIX fibers were located at the proximal and middle locations compared with the distal LOC (P < 0.01). ST color and color-stability characteristics were influenced by DOD and LOC, which may partially be explained by differences in fiber types among locations.


Assuntos
Bovinos/metabolismo , Consumo de Oxigênio , Carne Vermelha/normas , Animais , Cor , Músculos Isquiossurais/metabolismo , Metamioglobina/análise , Metamioglobina/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Mioglobina/análise , Mioglobina/metabolismo , NAD/análise , NAD/metabolismo , Distribuição Aleatória , Carne Vermelha/análise
4.
Nat Commun ; 11(1): 1049, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32103000

RESUMO

Enzymatic digestion for protein sequencing usually requires much time, and does not always result in high sequence coverage. Here we report the use of aqueous microdroplets to accelerate enzymatic reactions and, in particular, to improve protein sequencing. When a room temperature aqueous solution containing 10 µM myoglobin and 5 µg mL-1 trypsin is electrosonically sprayed (-3 kV) from a homemade setup to produce tiny (∼9 µm) microdroplets, we obtain 100% sequence coverage in less than 1 ms of digestion time, in sharp contrast to 60% coverage achieved by incubating the same solution at 37 °C for 14 h followed by analysis with a commercial electrospray ionization source that produces larger (∼60 µm) droplets. We also confirm the sequence of the therapeutic antibody trastuzumab (∼148 kDa), with a sequence coverage of 100% for light chains and 85% for heavy chains, demonstrating the practical utility of microdroplets in drug development.


Assuntos
Hormônio Adrenocorticotrópico/análise , Mioglobina/análise , Análise de Sequência de Proteína/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Trastuzumab/análise , Hormônio Adrenocorticotrópico/metabolismo , Enzimas Imobilizadas/química , Humanos , Mioglobina/metabolismo , Trastuzumab/metabolismo , Tripsina/metabolismo
5.
Food Chem ; 313: 126137, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31927210

RESUMO

Combined effects of gamma irradiation (0, 3, 6 and 9 kGy) and aging (1 and 14 days) on quality attributes of vacuum-packaged beef from Nellore cattle were evaluated. The meat water holding capacity was affected by irradiation, increasing (p < 0.05) purge and cooking loss regardless of the dose used. Irradiation negatively affected myofibrillar fragmentation, but samples irradiated at 9 kGy had (p < 0.05) higher soluble collagen and lower shear force values. The meat metmyoglobin reducing activity was reduced (p < 0.05) by the irradiation process, inducing the metmyoglobin accumulation with increasing dose applied. Samples irradiated at 9 kGy presented (p < 0.05) higher lipid oxidation and lower oxymyoglobin proportion and color redness and chroma values. It was concluded that irradiation at 9 kGy combined with aging can be used as an effective tool for improving the tenderness of Nellore beef, but resulted in a discoloration of the beef.


Assuntos
Raios gama , Carne Vermelha/efeitos da radiação , Animais , Brasil , Bovinos , Cor , Relação Dose-Resposta à Radiação , Embalagem de Alimentos , Qualidade dos Alimentos , Metamioglobina/análise , Metamioglobina/metabolismo , Mioglobina/análise , Mioglobina/metabolismo , Oxirredução , Carne Vermelha/análise , Vácuo
6.
Chem Commun (Camb) ; 56(10): 1513-1516, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-31919482

RESUMO

A potentiometric resolved photoelectrochemical (PEC) system based on CdS nanowires and SnNb2O6 nanosheets was developed. To prove the applicability of this system in PEC multi-biomarker analysis, a label free PEC immunosensor for two cardiac biomarkers, myoglobin and cardiac troponin I, was constructed.


Assuntos
Biomarcadores/análise , Técnicas Eletroquímicas/métodos , Nanoestruturas/química , Nanofios/química , Compostos de Estanho/química , Técnicas Biossensoriais , Compostos de Cádmio/química , Humanos , Mioglobina/análise , Sulfetos/química , Troponina I/análise
7.
J Biomol Tech ; 30(4): 50-57, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31662705

RESUMO

Methionine oxidation plays a critical role in many processes of biologic and biomedical importance, including cellular redox responses and stability of protein pharmaceuticals. Bottom-up methods for analysis of methionine oxidation can suffer from incomplete sequence coverage, as well as an inability to readily detect correlated oxidation between 2 or more methionines. However, the methodology for quantifying protein oxidation in top-down analyses is lacking. Previous work has shown that electron transfer dissociation (ETD)-based tandem mass spectrometry (MS/MS) fragmentation offers accurate and precise quantification of amino acid oxidation in peptides, even in complex samples. However, the ability of ETD-based MS/MS fragmentation to accurately quantify amino acid oxidation of proteins in a top-down manner has not been reported. Using apomyoglobin and calmodulin as model proteins, we partially converted methionines into methionine sulfoxide by incubation in H2O2. Using top-down ETD-based fragmentation, we quantified the amount of oxidation of various ETD product ions and compared the quantified values with those from traditional bottom-up analysis. We find that overall quantification of methionine oxidation by top-down MS/MS ranges from good agreement with traditional bottom-up methods to vast differences between the 2 techniques, including missing oxidized product ions and large differences in measured oxidation quantities. Care must be taken in transitioning ETD-based quantitation of oxidation from the peptide level to the intact protein level.


Assuntos
Metionina/metabolismo , Peptídeos/química , Proteínas/química , Espectrometria de Massas em Tandem/métodos , Apoproteínas/análise , Apoproteínas/química , Calmodulina/análise , Calmodulina/química , Peróxido de Hidrogênio/química , Radical Hidroxila/química , Metionina/análise , Metionina/química , Mioglobina/análise , Mioglobina/química , Oxirredução , Peptídeos/análise , Pegadas de Proteínas , Processamento de Proteína Pós-Traducional , Proteínas/análise , Reprodutibilidade dos Testes
8.
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
9.
PLoS One ; 14(7): e0220192, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31344091

RESUMO

It has been demonstrated that the plateau in the near-infrared spectroscopy (NIRS) derived deoxygenated hemoglobin and myoglobin (deoxy[Hb+Mb]) signal (i.e., deoxy[Hb+Mb]PLATEAU) towards the end of a ramp-incremental (RI) test does not represent the upper-limit in O2 extraction of the vastus lateralis (VL) muscle, given that an O2 extraction reserve has been recently observed. This study aimed to investigate whether this O2 extraction reserve was present in various populations and whether it exhibited sex- and/or training- related differences.Sixteen men- 8 untrained (27±5 years; 83±11 kg; 179±9 cm), 8 trained (27±4 years; 82±10 kg; 182±8 cm) and 9 trained women (27±2 years; 66±10 kg; 172±6 cm) performed a RI cycling test to exhaustion. The NIRS-derived deoxy[Hb+Mb] signal was measured continuously on the VL as a proxy for O2 extraction. A leg blood flow occlusion (i.e., ischemia) was performed at rest (LBFOCC 1) and immediately post the RI test (LBFOCC 2).No significant difference was found between the deoxy[Hb+Mb] amplitude during LBFOCC 1 and the deoxy[Hb+Mb]PLATEAU (p>0.05) nor between baseline (bsln) deoxy[Hb+Mb] values. deoxy[Hb+Mb] amplitude during LBFOCC 2 was significantly greater than LBFOCC 1 and at deoxy[Hb+Mb]PLATEAU (p<0.05) with group means ~30-45% higher than the deoxy[Hb+Mb]PLATEAU and LBFOCC 1 (p<0.05). No significant differences were found between groups in O2 extraction reserve, regardless of sex- or training-statusThe results of this study demonstrated the existence of an O2 extraction reserve in different populations, and that neither sex- nor training-related differences affect the amplitude of the reserve.


Assuntos
Exercício Físico/fisiologia , Perna (Membro)/irrigação sanguínea , Oxigênio/análise , Oxigênio/sangue , Fluxo Sanguíneo Regional/fisiologia , Adulto , Feminino , Hemodinâmica/fisiologia , Hemoglobinas/análise , Humanos , Perna (Membro)/cirurgia , Ligadura , Masculino , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/química , Mioglobina/análise , Oxigênio/isolamento & purificação , Consumo de Oxigênio/fisiologia , Condicionamento Físico Humano/fisiologia , Fatores Sexuais , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Adulto Jovem
10.
Electrophoresis ; 40(20): 2767-2774, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31172555

RESUMO

A novel analytical protocol was developed for general quality screening of chicken meat based on IEF and protein extraction. To demonstrate the developed protocol, 24 chickens were divided into three groups; each had eight chickens. The chickens in Group 1 were slaughtered by exsanguination, Group 2 asphyxiated in water, and that in Group 3 were infected by new castle disease virus. Proteins were extracted from the meat samples by using pure water as an extractant, separated by IEF, verified by western blot, and quantified via imaging analysis. The relevant experiments demonstrated that two myoglobin (Mb) bands were detected at pI 6.8 and 7.04 for all samples of Groups 1, 2, and 3, but there were additional hemoglobin (Hb) bands at pI 7.09 and 7.13 (P < 0.05) for the samples of Groups 2 and 3. The results implied that Hb bands might be a potential biomarker for the screening of chicken meat quality. The RSD values of two Mb bands (pI 6.8 and 7.04) in Group 1 were respectively 4.08 and 3.63%, the ones of two Hb bands (pI 7.09 and 7.13) in Group 2 were 3.66 and 2.10%, and those in Group 3 were 2.17% and 2.77%, respectively. All the RSD values indicated high stability and reliability of the developed protocol. Additionally, the protocol had a direct readout of protein bands in IEF without staining. However, it was time-consuming and had high cost. Even so, the relevant general method and finding have potential for screening of chicken meat quality.


Assuntos
Hemoglobinas/análise , Focalização Isoelétrica/métodos , Carne/análise , Carne/normas , Mioglobina/análise , Animais , Biomarcadores , Western Blotting , Galinhas , Reprodutibilidade dos Testes
11.
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
12.
Arch Pathol Lab Med ; 143(11): 1378-1381, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31116043

RESUMO

CONTEXT.­: Urine myoglobin testing is primarily indicated for diagnosis and risk assessment of kidney injury in patients with rhabdomyolysis. However, its utility is limited by a lack of rapid and reliable results. Myoglobin reacts positively for blood by urine dipstick, which can serve as an indicator of myoglobinuria. OBJECTIVE.­: To evaluate the performance and value of blood and red cell measurements by urinalysis as a surrogate test for myoglobinuria in routine clinical practice. DESIGN.­: This study is a retrospective observational study involving analysis of hemoglobin and red blood cell results by urinalysis in patients tested for urine myoglobin. RESULTS.­: A total of 13 139 urine myoglobin results from 88 Veterans Affairs facilities during a 15-year period ending in October 2014 were evaluated. Among methods used by each laboratory, qualitative urine myoglobin tests declined from 25 of 53 (47.1%) in 2000 to 5 of 77 (6.4%) in 2013. Of 7311 tests (55.6%) performed by quantitative methods with concomitant urinalysis, 3915 (53.5%) showed negative to trace blood results, of which myoglobin was 1000 µg/L or greater in 17 (0.4%). Among 1875 (25.5%) with 3+ (large) blood results, urine myoglobin was ≥1000 µg/L in 273 of 1533 (17.8%) with hematuria (≥5 red blood cells per microliter) and 109 of 342 (31.9%) without hematuria. CONCLUSIONS.­: Urinalysis results reliably predicted the absence of myoglobinuria and could be used to avert overtesting for urine myoglobin while also providing useful diagnostic information when urine myoglobin test results are not immediately available.


Assuntos
Hematúria/diagnóstico , Mioglobinúria/diagnóstico , Rabdomiólise/diagnóstico , Urinálise , Prática Clínica Baseada em Evidências , Hematúria/urina , Hemoglobinas/análise , Humanos , Mioglobina/análise , Mioglobinúria/urina , Estudos Retrospectivos , Rabdomiólise/urina , Estados Unidos , United States Department of Veterans Affairs
13.
Mikrochim Acta ; 186(5): 287, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30989406

RESUMO

The authors describe a fluorometric assay for cardiac myoglobin (Mb), a marker for myocardial infarction. An Mb-binding aptamer was labeled with pyrene and adsorbed on the surface of graphene oxide (GO) via noncovalent and reversible binding forces. This causes the fluorescence of pyrene (best measured at excitation/emission wavelengths of 275/376 nm) to be quenched. However, fluorescence is restored on addition of pyrene due to the strong affinity between Mb and aptamer which causes its separation from GO. Fluorescence increases linearly in the 5.6-450 pM Mb concentration range, and the lower detection limit is 3.9 pM (S/N = 3). The assay was applied to the determination of cardiac Mb in spiked serum, and satisfactory results were obtained. Graphical abstract Schematic presentation of the detection of Mb (cardiac myoglobin) by using a fluorometric method based on pyrene-modified anti-Mb aptamer and GO (graphene oxide) through fluorescence quenching and subsequent recovery.


Assuntos
Aptâmeros de Nucleotídeos/metabolismo , Técnicas Biossensoriais/métodos , Grafite/química , Miocárdio/metabolismo , Mioglobina/análise , Pirenos/química , Transferência de Energia , Fluorometria , Humanos , Limite de Detecção , Mioglobina/metabolismo
14.
J Am Soc Mass Spectrom ; 30(8): 1435-1445, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30972727

RESUMO

Capillary zone electrophoresis-electrospray ionization-tandem mass spectrometry (CZE-ESI-MS/MS) has attracted attention recently for top-down proteomics because it can achieve highly efficient separation and very sensitive detection of proteins. However, separation window and sample loading volume of CZE need to be boosted for a better proteome coverage using CZE-MS/MS. Here, we present an improved CZE-MS/MS system that achieved a 180-min separation window and a 2-µL sample loading volume for top-down characterization of protein mixtures. The system obtained highly efficient separation of proteins with nearly one million theoretical plates for myoglobin and enabled baseline separation of three different proteoforms of myoglobin. The CZE-MS/MS system identified 797 ± 21 proteoforms and 258 ± 7 proteins (n = 2) from an Escherichia coli (E. coli) proteome sample in a single run with only 250 ng of proteins injected. The system still identified 449 ± 40 proteoforms and 173 ± 6 proteins (n = 2) from the E. coli sample when only 25 ng of proteins were injected per run. Single-shot CZE-MS/MS analyses of zebrafish brain cerebellum (Cb) and optic tectum (Teo) regions identified 1730 ± 196 proteoforms (n = 3) and 2024 ± 255 proteoforms (n = 3), respectively, with only 500-ng proteins loaded per run. Label-free quantitative top-down proteomics of zebrafish brain Cb and Teo regions revealed significant differences between Cb and Teo regarding the proteoform abundance. Over 700 proteoforms from 131 proteins had significantly higher abundance in Cb compared to Teo, and these proteins were highly enriched in several biological processes, including muscle contraction, glycolytic process, and mesenchyme migration. Graphical Abstract.


Assuntos
Proteínas/análise , Proteômica/métodos , Animais , Bovinos , Eletroforese Capilar/métodos , Escherichia coli/química , Proteínas de Escherichia coli/análise , Cavalos , Mioglobina/análise , Proteoma/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
15.
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
16.
Anal Biochem ; 569: 31-38, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30707897

RESUMO

The effects of incubation temperature and acetonitrile (ACN) amount on microwave-assisted tryptic digestion of horse skeletal muscle myoglobin (MYG) and bovine serum albumin (BSA) were investigated. Microwave-assisted tryptic digestion was performed on BSA or MYG solutions containing different amounts (0, 10, and 20%) of ACN for different times (10, 20, 30, 40, and 50 min) at different temperatures (25, 37, and 55 °C). Conventional overnight tryptic digestion was also conducted with gentle mixing at 37 °C for 16 h. Digested samples were analyzed using matrix-assisted laser desorption/ionization mass spectrometry. Similar sequence coverage (SC) values were obtained under most conditions except when the protein sample solutions were digested with 20% ACN at 55 °C, which provided the lowest SC for both MYG and BSA for all investigated digestion times. Considering the missed cleavage (MC) ratios for 50-min microwave-assisted digestion, the highest MC ratio, (i.e., lowest trypsin activity) was observed for the digestion condition of 20% ACN at 55 °C for both proteins, while the lowest MC ratio was observed with 0% ACN at 25 °C for MYG and with 0% ACN at 55 °C for BSA. Conventional overnight tryptic digestion at 37 °C provided more completely cleaved peptides than 50-min microwave-assisted tryptic digestion at the same temperature.


Assuntos
Acetonitrilos/química , Micro-Ondas , Peptídeos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Tripsina/metabolismo , Animais , Bovinos , Cavalos , Mioglobina/análise , Mioglobina/metabolismo , Peptídeos/metabolismo , Soroalbumina Bovina/análise , Soroalbumina Bovina/metabolismo , Temperatura
17.
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
18.
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
19.
Meat Sci ; 149: 31-39, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30453278

RESUMO

The objective of this study was to determine the effects of feeding endophyte-infected tall fescue seeds to Angus steers during the stocker phase on the quality attributes of beef strip steaks during retail display. Endophyte-infected tall fescue seeds had no effect on steak surface lean color, myoglobin forms, proximate composition, thiobarbituric acid reactive substances, aerobic plate count, pH, activity of superoxide dismutase and metmyoglobin reductase, shear force, and sensory attributes (P ≥ 0.087). However, lightness, redness, oxymyoglobin percentage, and MRA decreased from 45.01, 32.60, 67.61%, and 9.54 µM/min/g, respectively, on d 0 to 40.11, 21.83, 48.95%, and 2.30 µM/min/g, respectively, on d 7 (P ≤ 0.001). Thiobarbituric acid reactive substances were increased by 30% by d 5 (P = 0.015) and APC was increased by 0.5 log CFU/g by d 7 (P ≤ 0.012).


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Endófitos , Festuca/microbiologia , Carne Vermelha/análise , Animais , Carga Bacteriana , Cor , Humanos , Masculino , Músculo Esquelético/química , Mioglobina/análise , Carne Vermelha/microbiologia , Carne Vermelha/normas , Sementes/microbiologia , Resistência ao Cisalhamento , Substâncias Reativas com Ácido Tiobarbitúrico/análise
20.
Clin Exp Nephrol ; 23(1): 32-42, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29961156

RESUMO

BACKGROUND: Chronic kidney disease (CKD) patients have reduced exercise capacity. Possible contributing factors may include impaired muscle O2 utilisation through reduced mitochondria number and/or function slowing the restoration of muscle ATP concentrations via oxidative phosphorylation. Using near-infrared spectroscopy (NIRS), we explored changes in skeletal muscle haemoglobin/myoglobin O2 saturation (SMO2%) during exercise. METHODS: 24 CKD patients [58.3 (± 16.5) years, eGFR 56.4 (± 22.3) ml/min/1.73 m2] completed the incremental shuttle walk test (ISWT) as a marker of exercise capacity. Using NIRS, SMO2% was measured continuously before, during, and after (recovery) exercise. Exploratory differences were investigated between exercise capacity tertiles in CKD, and compared with six healthy controls. RESULTS: We identified two discrete phases; a decline in SMO2% during incremental exercise, followed by rapid increase upon cessation (recovery). Compared to patients with low exercise capacity [distance walked during ISWT, 269.0 (± 35.9) m], patients with a higher exercise capacity [727.1 (± 38.1) m] took 45% longer to reach their minimum SMO2% (P = .038) and recovered (half-time recovery) 79% faster (P = .046). Compared to controls, CKD patients took significantly 56% longer to recover (i.e., restore SMO2% to baseline, full recovery) (P = .014). CONCLUSIONS: Using NIRS, we have determined for the first time in CKD, that favourable SMO2% kinetics (slower deoxygenation rate, quicker recovery) are associated with greater exercise capacity. These dysfunctional kinetics may indicate reduced mitochondria capacity to perform oxidative phosphorylation-a process essential for carrying out even simple activities of daily living. Accordingly, NIRS may provide a simple, low cost, and non-invasive means to evaluate muscle O2 kinetics in CKD.


Assuntos
Exercício Físico , Hemoglobinas/metabolismo , Músculo Esquelético/metabolismo , Insuficiência Renal Crônica/metabolismo , Adulto , Idoso , Limiar Anaeróbio , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Teste de Esforço , Feminino , Taxa de Filtração Glomerular , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Mioglobina/análise , Mioglobina/metabolismo , Consumo de Oxigênio , Espectroscopia de Luz Próxima ao Infravermelho
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA