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1.
BMC Infect Dis ; 24(1): 842, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39164612

RESUMEN

AIM: This study aimed to discover risk factors for death in patients with critical COVID-19 infection in order to identify patients with a higher risk of death at an early stage. METHODS: We retrospectively analyzed the clinical data of patients with critical COVID-19 infection from April 2022 to June 2022. Data were collected from the electronic medical records. Propensity matching scores were used to reduce the effect of confounding factors, such as patient baseline variables. Independent risk factors affecting patient prognosis were assessed using univariate logistic regression and multivariate logistic regression analysis. Restricted cubic spline curves were used to assess the relationship between independent and dependent variables. RESULTS: The data of 132 patients with critical COVID-19 infection were included in the study. Of the 132 patients, 79 survived and 53 died. Among laboratory indicators, patients who died had higher proportions of abnormalities in procalcitonin, aspartate aminotransferase (AST), creatinine, cardiac troponin I, and myoglobin. Univariate and multivariate logistic regression analyses suggested that abnormal AST (OR = 4.98, P = 0.02), creatinine (OR = 7.93, P = 0.021), and myoglobin (OR = 103.08, P = 0.002) were independent risk factors for death. After correction for AST and creatinine, a linear relationship between myoglobin and risk of death in patients was found using restricted cubic splines. CONCLUSION: High myoglobin level is an independent risk factor for death and is therefore a prognostic marker in elderly patients with severe COVID-19 infection.


Asunto(s)
COVID-19 , Mioglobina , SARS-CoV-2 , Humanos , COVID-19/mortalidad , COVID-19/sangre , Femenino , Masculino , Anciano , Estudios Retrospectivos , Factores de Riesgo , Mioglobina/sangre , Estudios de Casos y Controles , Anciano de 80 o más Años , Persona de Mediana Edad , Pronóstico , China/epidemiología , Aspartato Aminotransferasas/sangre
2.
Nat Commun ; 15(1): 5714, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38977701

RESUMEN

Genetic code expansion has emerged as a powerful tool for precisely introducing unnatural chemical structures into proteins to improve their catalytic functions. Given the high catalytic propensity of histidine in the enzyme pocket, increasing the chemical diversity of catalytic histidine could result in new characteristics of biocatalysts. Herein, we report the genetically encoded Nδ-Vinyl Histidine (δVin-H) and achieve the wild-type-like incorporation efficiency by the evolution of pyrrolysyl tRNA synthetase. As histidine usually acts as the nucleophile or the metal ligand in the catalytic center, we replace these two types of catalytic histidine to δVin-H to improve the performance of the histidine-involved catalytic center. Additionally, we further demonstrate the improvements of the hydrolysis activity of a previously reported organocatalytic esterase (the OE1.3 variant) in the acidic condition and myoglobin (Mb) catalyzed carbene transfer reactions under the aerobic condition. As histidine is one of the most frequently used residues in the enzyme catalytic center, the derivatization of the catalytic histidine by δVin-H holds a great potential to promote the performance of biocatalysts.


Asunto(s)
Dominio Catalítico , Histidina , Histidina/metabolismo , Histidina/química , Histidina/genética , Mioglobina/genética , Mioglobina/química , Mioglobina/metabolismo , Biocatálisis , Catálisis , Aminoacil-ARNt Sintetasas/genética , Aminoacil-ARNt Sintetasas/metabolismo , Aminoacil-ARNt Sintetasas/química , Esterasas/genética , Esterasas/metabolismo , Esterasas/química , Hidrólisis , Escherichia coli/genética , Escherichia coli/metabolismo
3.
J Phys Chem B ; 128(30): 7350-7361, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39034688

RESUMEN

We advance the quality of first-principles calculations of protein electronic circular dichroism (CD) through an amelioration of a key deficiency of a previous procedure that involved diabatization of electronic states on the amide chromophore (to obtain interamide couplings) in a ß-strand conformation of a diamide. This yields substantially improved calculated far-ultraviolet (far-UV) electronic circular dichroism (CD) spectra for ß-sheet conformations. The interamide couplings from the diabatization procedure for 13 secondary structural elements (13 diamide structures) are applied to compute the CD spectra for seven example proteins: myoglobin (α helix), jacalin (ß strand), concanavalin A (ß type I), elastase (ß type II), papain (α + ß), 310-helix bundle (310-helix) and snow flea antifreeze protein (polyproline). In all cases, except concanavalin A and papain, the CD spectra computed using the interamide couplings from the diabatization procedure yield improved agreement with experiment with respect to previous first-principles calculations.


Asunto(s)
Dicroismo Circular , Concanavalina A , Concanavalina A/química , Mioglobina/química , Proteínas/química , Papaína/química , Papaína/metabolismo , Péptidos/química , Electrones , Elastasa Pancreática/química , Elastasa Pancreática/metabolismo , Estructura Secundaria de Proteína
4.
Sci Rep ; 14(1): 16337, 2024 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-39014025

RESUMEN

It has been suggested that sodium-glucose cotransporter 2 (SGLT2) inhibitors have cardioprotective effects during myocardial ischemia/reperfusion (I/R) independent of glucose-lowering action. However, the effects of SGLT2 inhibitors on structural damage to cardiomyocytes in the ischemic region during I/R remain unknown. We applied a microdialysis technique to the heart of anesthetized rats and investigated the effects of an SGLT2 inhibitor, dapagliflozin, on myocardial interstitial myoglobin levels in the ischemic region during coronary occlusion followed by reperfusion. Dapagliflozin was administered systemically (40 µg/body iv) or locally via a dialysis probe (100 µM and 1 mM) 30 min before coronary occlusion. In the vehicle group, coronary occlusion increased the dialysate myoglobin concentration in the ischemic region. Reperfusion further increased the dialysate myoglobin concentration. Intravenous administration of dapagliflozin reduced dialysate myoglobin concentration during ischemia and at 0-15 min after reperfusion, but local administration (100 µM and 1 mM) did not. Therefore, acute systemic administration of dapagliflozin prior to ischemia has cardioprotective effects on structural damage during I/R.


Asunto(s)
Compuestos de Bencidrilo , Glucósidos , Daño por Reperfusión Miocárdica , Miocitos Cardíacos , Mioglobina , Animales , Compuestos de Bencidrilo/farmacología , Mioglobina/metabolismo , Glucósidos/farmacología , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Ratas , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/efectos de los fármacos , Masculino , Inhibidores del Cotransportador de Sodio-Glucosa 2/farmacología , Microdiálisis
5.
BMC Nephrol ; 25(1): 247, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39085790

RESUMEN

BACKGROUND: Rhabdomyolysis describes a syndrome characterized by muscle necrosis and the subsequent release of creatine kinase and myoglobin into the circulation. Myoglobin elimination with extracorporeal hemoadsorption has been shown to effectively remove myoglobin from the circulation. Our aim was to provide best practice consensus statements developed by the Hemoadsorption in Rhabdomyolysis Task Force (HRTF) regarding the use of hemadsorption for myoglobin elimination. METHODS: A systematic literature search was performed until 11th of January 2023, after which the Rhabdomyolysis RTF was assembled comprising international experts from 6 European countries. Online conferences were held between 18th April - 4th September 2023, during which 37 consensus questions were formulated and using the Delphi process, HRTF members voted online on an anonymised platform. In cases of 75 to 90% agreement a second round of voting was performed. RESULTS: Using the Delphi process on the 37 questions, strong consensus (> 90% agreement) was achieved in 12, consensus (75 to 90% agreement) in 10, majority (50 to 74%) agreement in 13 and no consensus (< 50% agreement) in 2 cases. The HRTF formulated the following recommendations: (1) Myoglobin contributes to the development of acute kidney injury; (2) Patients with myoglobin levels of > 10,000 ng/ml should be considered for extracorporeal myoglobin removal by hemoadsorption; (3) Hemoadsorption should ideally be started within 24 h of admission; (4) If myoglobin cannot be measured then hemoadsorption may be indicated based on clinical picture and creatinine kinase levels; (5) Cartridges should be replaced every 8-12 h until myoglobin levels < 10,000 ng/ml; (6) In patients with acute kidney injury, hemoadsorption can be discontinued before dialysis is terminated and should be maintained until the myoglobin concentration values are consistently < 5000 ng/ml. CONCLUSIONS: The current consensus of the HRTF support that adjuvant hemoadsorption therapy in severe rhabdomyolysis is both feasible and safe and may be an effective method to reduce elevated circulating levels of myoglobin.


Asunto(s)
Mioglobina , Rabdomiólisis , Humanos , Rabdomiólisis/terapia , Mioglobina/sangre , Hemabsorción , Técnica Delphi , Consenso
6.
Meat Sci ; 216: 109590, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38991480

RESUMEN

The packaging system is one of the factors influencing the preservation of the nutritional value, microbiological safety, and sensory attributes of meat. The study investigated changes in physicochemical and microbiological properties taking place during 15-day refrigerated storage of two calf muscles, the longissimus lumborum (LL) and semitendinosus (ST), packaged in three systems, respectively, vacuum packing (VP), modified atmosphere packaging (MAP, 80% O2 + 20% CO2), and a combined system (VP + MAP, 8 d in VP followed by 7 d in MAP). LL and ST stored in VP had significantly lower levels of lipid oxidation, higher α-tocopherol content, and higher instrumentally measured tenderness in comparison with the samples stored in MAP. On the other hand, the MAP samples had lower purge loss at 5 and 15 days, a higher proportion of oxymyoglobin up to 10 days of storage, and a better microbiological status. Calf muscle samples stored in the VP + MAP system had intermediate values for TBARS and α-tocopherol content and at the same time were the most tender and had the lowest counts of Pseudomonas and Enterobacteriaceae bacteria at 15 days. All packaging systems ensured relatively good quality of veal characteristics up to the last day of storage. However, for MAP at 15 days of storage, unfavourable changes in colour (a high level of metmyoglobin and a decrease in oxymyoglobin, redness and R630/580 ratio) and in the lipid fraction (a high TBARS value and a significant decrease in α-tocopherol content) were observed.


Asunto(s)
Embalaje de Alimentos , Almacenamiento de Alimentos , Músculo Esquelético , Carne Roja , Sustancias Reactivas al Ácido Tiobarbitúrico , alfa-Tocoferol , Embalaje de Alimentos/métodos , Animales , Bovinos , alfa-Tocoferol/análisis , Vacio , Músculo Esquelético/química , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Carne Roja/análisis , Carne Roja/microbiología , Color , Microbiología de Alimentos , Mioglobina/análisis , Peroxidación de Lípido , Enterobacteriaceae/aislamiento & purificación , Pseudomonas
7.
Vitam Horm ; 125: 31-46, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38997168

RESUMEN

Post-translational modification of proteins by Maillard reaction, known as glycation, is thought to be the root cause of different complications, particularly in diabetes mellitus and age-related disorders. Methylglyoxal (MG), a reactive α-oxoaldehyde, increases in diabetic condition and reacts with the proteins to form advanced glycation end products (AGEs) following a Maillard-like reaction. In a time-dependent reaction study of MG with the heme protein myoglobin (Mb), MG was found to induce significant structural alterations of the heme protein, such as heme loss, changes in tryptophan fluorescence, and decrease of α-helicity with increased ß-sheet content. These changes were found to occur gradually with increasing period of incubation. Incubation of Mb with MG induced the formation of several AGE adducts, including, carboxyethyllysine at Lys-16, carboxymethyllysine at Lys-87, carboxyethyllysine or pyrraline-carboxymethyllysine at Lys-133, carboxyethyllysine at Lys-42 and hydroimidazolone or argpyrimidine at Arg-31 and Arg-139. MG induced amyloid-like aggregation of Mb was detected at a longer period of incubation. MG-derived AGEs, therefore, appear to have an important role as the precursors of protein aggregation, which, in turn, may be associated with pathophysiological complications.


Asunto(s)
Productos Finales de Glicación Avanzada , Mioglobina , Agregado de Proteínas , Piruvaldehído , Animales , Humanos , Productos Finales de Glicación Avanzada/metabolismo , Glicosilación , Reacción de Maillard , Mioglobina/metabolismo , Mioglobina/química , Procesamiento Proteico-Postraduccional , Piruvaldehído/metabolismo
8.
J Am Soc Mass Spectrom ; 35(7): 1507-1515, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38905484

RESUMEN

Over the past decades, proteomics has become increasingly important and a heavily discussed topic. The identification of intact proteins remains a major focus in this field. While most intact proteins are analyzed using high-resolution mass spectrometry, identifying them through low-resolution mass spectrometry continues to pose challenges. In our study, we investigated the capability of identifying various intact proteins using collision-induced dissociation (CID) and electron transfer without dissociation (ETnoD). Using myoglobin as our test protein, stable product ions were generated with CID, and the identities of the product ions were identified with ETnoD. ETnoD uses a short activation time (AcT, 5 ms) to create sequential charge-reduced precursor ion (CRI). The charges of the fragments and their sequences were determined with corresponding CRI. The product ions can be selected for subsequent CID (termed CIDn) combined with ETnoD for further sequence identification and validation. We refer to this method as CIDn/ETnoD. The use of a multistage CID activation (CIDn) and ETnoD protocol has been applied to several intact proteins to obtain multiple sequence identifications.


Asunto(s)
Mioglobina , Proteómica , Mioglobina/química , Mioglobina/análisis , Proteómica/métodos , Animales , Proteínas/química , Proteínas/análisis , Secuencia de Aminoácidos , Caballos , Espectrometría de Masas/métodos , Datos de Secuencia Molecular , Espectrometría de Masas en Tándem/métodos
9.
Toxicon ; 247: 107835, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-38942240

RESUMEN

Serine peptidases and metallopeptidases are the primary toxins found in Bothrops snakes venoms, which act on proteins in the tissues of victims or prey, and release of peptides formed through proteolytic activity. Various studies have indicated that these peptides, released by the proteolytic activity of heterologous enzymes, generate molecules with unidentified functions, referred to as cryptids. To address this, we purified serine peptidases from Bothrops jararaca venom using molecular exclusion chromatography and then incubated them with the endogenous substrate myoglobin. As a control, we also incubated the substrate with trypsin. The resulting proteolytic fragments were analyzed, separated, and collected via HPLC. These fractions were then tested on cell cultures, the active fractions were sequenced (ALELFR and TGHPETLEK) and synthesized. After confirming their activity, the peptides underwent sequencing and synthesis for additional cell tests, including the increase of cell viability, cycle phases, proliferation, signaling, growth kinetics, angiogenesis, and migration. The results revealed that the synthesized peptides exhibited cellular repair properties, suggesting a potential role in tissue repair in the range of 0.05-5 µ M. Additionally, the effects of fragments resulting from myoglobin degradation isolated (ALELFR and TGHPETLEK) revealed a regenerative action on tissue.


Asunto(s)
Bothrops , Venenos de Crotálidos , Mioglobina , Serina Proteasas , Animales , Venenos de Crotálidos/química , Serina Proteasas/metabolismo , Serina Proteasas/química , Mioglobina/metabolismo , Péptidos/farmacología , Péptidos/química , Humanos , Supervivencia Celular/efectos de los fármacos , Bothrops jararaca
10.
Food Chem ; 456: 140022, 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-38876067

RESUMEN

This study compared the proteomics of beef patties under high­oxygen modified atmosphere packaging (HiOx-MAP) and vacuum packaging (VP) during heating. The color and oxidation stability of fresh patties, and myoglobin denaturation of cooked patties were also measured. The results suggested that HiOx-MAP patties contained more oxymyoglobin in fresh meat and had higher myoglobin denaturation during heating than VP patties, resulting in premature browning (PMB) during cooking. Proteomic analysis found that the overabundance of proteasome subunit beta type-2 (PSMB2) and peroxiredoxin-2 (PRDX2) in HiOx-55 °C, which can remove the damaged proteins and inhibit oxidation respectively, are of benefit to meat color stability during storage, however, this was still insufficient to inhibit the occurrence of PMB during cooking. The high abundance of lamin B1 (LMNB1) in VP-55 °C can maintain the stability of meat color. This research provides greater understanding, based on proteomic perspectives, of the molecular mechanism of PMB.


Asunto(s)
Embalaje de Alimentos , Oxígeno , Proteómica , Bovinos , Animales , Embalaje de Alimentos/instrumentación , Oxígeno/química , Culinaria , Color , Oxidación-Reducción , Productos de la Carne/análisis , Calor , Mioglobina/química , Mioglobina/análisis
11.
J Inorg Biochem ; 258: 112633, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38852292

RESUMEN

The NO dioxygenation reaction catalyzed by heme-containing globin proteins is a crucial aerobic detoxification pathway. Accordingly, the second order reaction of NO with oxymyoglobin and oxyhemoglobin has been the focus of a large number of kinetic and spectroscopic studies. Stopped-flow and rapid-freeze-quench (RFQ) measurements have provided evidence for the formation of a Fe(III)-nitrato complex with millisecond lifetime prior to release of the nitrate product, but the temporal resolution of these techniques is insufficient for the characterization of precursor species. Most mechanistic models assume the formation of an initial Fe(III)-peroxynitrite species prior to homolytic cleavage of the OO bond and recombination of the resulting NO2 and Fe(IV)=O species. Here we report vibrational spectroscopy measurements for the reaction of oxymyoglobin with a photolabile caged NO donor at cryogenic temperatures. We show that this approach offers efficient formation and trapping of the Fe(III)-nitrato, enzyme-product, complex at 180 K. Resonance Raman spectra of the Fe(III)-nitrato complex trapped via RFQ in the liquid phase and photolabile NO release at cryogenic temperatures are indistinguishable, demonstrating the complementarity of these approaches. Caged NO is released by irradiation <180 K but diffusion into the heme pocket is fully inhibited. Our data provide no evidence for Fe(III)-peroxynitrite of Fe(IV)=O species, supporting low activation energies for the NO to nitrate conversion at the oxymyoglobin reaction site. Photorelease of NO at cryogenic temperatures allows monitoring of the reaction by transmittance FTIR which provides valuable quantitative information and promising prospects for the detection of protein sidechain reorganization events in NO-reacting metalloenzymes.


Asunto(s)
Mioglobina , Óxido Nítrico , Mioglobina/química , Óxido Nítrico/química , Espectrometría Raman , Frío , Animales , Cinética , Vibración
12.
Meat Sci ; 216: 109551, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38852287

RESUMEN

Packaging material should guarantee the longest possible shelf life of food and help to maintain its quality. The aim of the study was to assess the physicochemical changes taking place during 28-day ageing of beef steaks packed in two types of multilayer films containing biodegradable polymers - polylactic acid (NAT/PLA) and Mater-Bi® (NAT/MBI). The control group consisted of steaks packed in synthetic polyamide/polyethylene (PA/PE) film. The samples stored in NAT/PLA had significantly lower purge loss than the control samples and the lowest expressible water amount after 14 and 21 days. Following blooming, the most favourable colour was shown in steaks stored in NAT/MBI, with the highest values for the L*, a* and C* parameters and the R630/580 ratio, a high proportion of oxymyoglobin, and the lowest share of metmyoglobin. All steaks, regardless of the type of packaging material, had acceptable tenderness and were stable in terms of lipid oxidation.


Asunto(s)
Color , Embalaje de Alimentos , Poliésteres , Carne Roja , Embalaje de Alimentos/métodos , Bovinos , Animales , Vacio , Carne Roja/análisis , Poliésteres/química , Mioglobina/análisis , Metamioglobina/análisis , Polietileno/química , Nylons/química , Almacenamiento de Alimentos
13.
Rev Assoc Med Bras (1992) ; 70(suppl 1): e2024S106, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38865526

RESUMEN

BACKGROUND: Chemotherapy with doxorubicin may lead to left ventricular dysfunction. There is a controversial recommendation that biomarkers can predict ventricular dysfunction, which is one of the most feared manifestations of anthracycline cardiotoxicity. OBJECTIVE: The aim of this study was to evaluate the behavior of biomarkers such as Troponin I, type B natriuretic peptide, creatine phosphokinase fraction MB, and myoglobin in predicting cardiotoxicity in a cohort of women with breast cancer undergoing chemotherapy with anthracycline. METHODS: This is an observational, prospective, longitudinal, unicentric study, which included 40 women with breast cancer, whose therapeutic proposal included treatment with doxorubicin. The protocol had a clinical follow-up of 12 months. Biomarkers such as Troponin I, type B natriuretic peptide, creatine phosphokinase fraction MB, and myoglobin were measured pre-chemotherapy and after the first, third, fourth, and sixth cycles of chemotherapy. RESULTS: There was a progressive increase in type B natriuretic peptide and myoglobin values in all chemotherapy cycles. Although creatine phosphokinase fraction MB showed a sustained increase, this increase was not statistically significant. Troponin, type B natriuretic peptide, myoglobin, and creatine phosphokinase fraction MB were the cardiotoxicity markers with the earliest changes, with a significant increase after the first chemotherapy session. However, they were not able to predict cardiotoxicity. CONCLUSION: Troponin I, type B natriuretic peptide, myoglobin, and creatine phosphokinase fraction MB are elevated during chemotherapy with doxorubicin, but they were not able to predict cardiotoxicity according to established clinical and echocardiographic criteria. The incidence of subclinical cardiotoxicity resulting from the administration of doxorubicin was 12.5%.


Asunto(s)
Biomarcadores , Neoplasias de la Mama , Cardiotoxicidad , Doxorrubicina , Mioglobina , Troponina I , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Estudios Prospectivos , Troponina I/sangre , Doxorrubicina/efectos adversos , Cardiotoxicidad/etiología , Persona de Mediana Edad , Biomarcadores/sangre , Mioglobina/sangre , Adulto , Antibióticos Antineoplásicos/efectos adversos , Péptido Natriurético Encefálico/sangre , Anciano , Forma MB de la Creatina-Quinasa/sangre , Estudios Longitudinales , Antraciclinas/efectos adversos , Disfunción Ventricular Izquierda/inducido químicamente , Valor Predictivo de las Pruebas
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124644, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-38901235

RESUMEN

Reaction between the polymeric [RuCl2(CO)2]n and the N,N-bidentate ligand, 8-amino-quinoline (Quin), in methanol, afforded the photoactivated CO releasing molecule with the formula of trans-(Cl,Cl)-[RuCl2(CO)2Quin]. In the presence of biomolecules or in solvents with varying polarity and coordinating abilities, the solvatochromic characteristics and dark stability were investigated. A new board band emerged in the visible spectrum during the illumination, and its position varies according to the type of solvent used, indicating the role of the solvent in controlling the nature of the CO-depleted species. Spectral methods were used in combination with density functional theory simulations to get insight into the local minimum structure and the electronic properties of the Ru(II) complex. The results of the myoglobin assay showed that within the first two hours of illumination, one of the two CO molecules was released. The cytotoxic properties of the Ru(II)-based complex were investigated against normal mice bone marrow stromal cells and malignant human acute monocytic leukaemia cells.


Asunto(s)
Aminoquinolinas , Monóxido de Carbono , Complejos de Coordinación , Rutenio , Animales , Ratones , Humanos , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Aminoquinolinas/química , Aminoquinolinas/farmacología , Rutenio/química , Rutenio/farmacología , Ligandos , Monóxido de Carbono/química , Mioglobina/química , Teoría Funcional de la Densidad , Luz
15.
Anal Chim Acta ; 1312: 342749, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38834263

RESUMEN

Carbon monoxide (CO) is an innate signaling molecule that can regulate immune responses and interact with crucial elements of the circadian clock. Moreover, pharmacologically, CO has been substantiated for its therapeutic advantages in animal models of diverse pathological conditions. Given that an excessive level of CO can be toxic, it is imperative to quantify the necessary amount for therapeutic use accurately. However, estimating gaseous CO is notably challenging. Therefore, novel techniques are essential to quantify CO in therapeutic applications and overcome this obstacle precisely. The classical Myoglobin (Mb) assay technique has been extensively used to determine the amount of CO-release from CO-releasing molecules (CORMs) within therapeutic contexts. Nevertheless, specific challenges arise when applying the Mb assay to evaluate CORMs featuring innovative molecular architectures. Here, we report a fluorinated photo-CORM (CORM-FBS) for the photo-induced CO-release. We employed the 19F NMR spectroscopy approach to monitor the release of CO as well as quantitative evaluation of CO release. This new 19F NMR approach opens immense opportunities for researchers to develop reliable techniques for identifying molecular structures, quantitative studies of drug metabolism, and monitoring the reaction process.


Asunto(s)
Monóxido de Carbono , Luz , Mioglobina , Monóxido de Carbono/análisis , Mioglobina/química , Espectroscopía de Resonancia Magnética/métodos , Flúor/química , Animales , Procesos Fotoquímicos
16.
Structure ; 32(6): 650-651, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38848681

RESUMEN

In a recent issue of Nature, Barends et al.1 studied the photodissociation of carboxymyoglobin with ultrafast laser pump-probe serial femtosecond crystallography experiments. They observed significant differences in heme protein structural dynamics for biologically relevant 1-photon excitation relative to high excitation leading to the absorption of several photons per heme.


Asunto(s)
Mioglobina , Mioglobina/química , Conformación Proteica , Hemo/química , Cristalografía por Rayos X , Luz , Fotones , Modelos Moleculares
17.
Meat Sci ; 215: 109548, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38838568

RESUMEN

This study aimed to develop an appropriate modified atmosphere packaging (MAP) system for displayed beef steaks following long-term superchilled (-1 °C) storage. After superchilled storage for 0, 2, 8, or 16 weeks, beef loins were fabricated into steaks and displayed with 20%, 50%, or 80% O2-MAP under chilled conditions. At each storage point, after display for 0, 3, 7, or 10 days, instrumental color, myoglobin redox forms percentage, lipid oxidation, total viable count (TVC), and total volatile basic nitrogen (TVB-N) were evaluated. Meat color stability decreased, with prolonged storage period and display time. When the storage period was within 8 weeks, under all the above MAP conditions, the display time for the beef steaks was up to 10 days. Considering 80% O2-MAP promoted lipid oxidation, 50% and 80% O2-MAP were not recommended for displaying steaks for more than 10 and 7 days respectively after 16 weeks of storage. However, 20%, 50%, or 80% O2-MAP could maintain 3 days of microbial shelf-life according to TVC and TVB-N results. Additionally, after long-term superchilled storage for 16 weeks, the various O2 concentrations had minimal impact on microbiota succession during the MAP display period. Furthermore, beef steaks packaged under various MAP systems exhibited similar microbial compositions, with the dominant bacteria alternating between Lactobacillus and Carnobacterium. This study provided practical guidance for improving beef color stability after long-term superchilled storage.


Asunto(s)
Color , Microbiología de Alimentos , Embalaje de Alimentos , Almacenamiento de Alimentos , Oxígeno , Carne Roja , Bovinos , Embalaje de Alimentos/métodos , Animales , Carne Roja/microbiología , Carne Roja/análisis , Mioglobina , Frío , Oxidación-Reducción , Bacterias
18.
ACS Appl Mater Interfaces ; 16(25): 32794-32811, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38860871

RESUMEN

This paper reports a microfluidic device for the electrochemical and plasmonic detection of cardiac myoglobin (cMb) and cardiac troponin I (cTnI) with noticeable limits of detection (LoD) as low as a few picograms per milliliter (pg/mL) ranges, achieved in a short detection time. The device features two working electrodes, each with a mesoporous Ni3V2O8 nanoscaffold grafted with reduced graphene oxide (rGO) that improves the interaction of diffusing analyte molecules with the sensing surface by providing a high surface area and reaction kinetics. Electrochemical studies reveal sensitivities as high as 9.68 µA ng/mL and a LoD of 2.0 pg/mL for cTnI, and 8.98 µA ng/mL and 4.7 pg/mL for cMb. Additionally, the surface plasmon resonance (SPR) studies demonstrate a low-level LoD of 8.8 pg/mL for cMb and 7.3 pg/mL for cTnI. The dual-modality sensor enables dynamic tracking of kinetic antigen-antibody interactions during sensing, self-verification through providing signals of two modes, and reduced false readout. This study demonstrates the complementary nature of the electrochemical and SPR modes in biosensing, with the electrochemical mode being highly sensitive and the SPR mode providing superior tracking of molecular recognition behaviors. The presented sensor represents a significant innovation in cardiovascular disease management and can be applied to monitor other clinically important biomolecules.


Asunto(s)
Técnicas Electroquímicas , Grafito , Infarto del Miocardio , Mioglobina , Resonancia por Plasmón de Superficie , Troponina I , Infarto del Miocardio/diagnóstico , Troponina I/análisis , Troponina I/sangre , Grafito/química , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Mioglobina/análisis , Resonancia por Plasmón de Superficie/instrumentación , Humanos , Porosidad , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Límite de Detección , Dispositivos Laboratorio en un Chip , Nanoestructuras/química
19.
Biophys Chem ; 311: 107269, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38815545

RESUMEN

Reverse micelles (RMs) are spontaneously organizing nanobubbles composed of an organic solvent, surfactants, and an aqueous phase that can encapsulate biological macromolecules for various biophysical studies. Unlike other RM systems, the 1-decanoyl-rac-glycerol (10MAG) and lauryldimethylamine-N-oxide (LDAO) surfactant system has proven to house proteins with higher stability than other RM mixtures with little sensitivity to the water loading (W0, defined by the ratio of water to surfactant). We investigated this unique property by encapsulating three model proteins - cytochrome c, myoglobin, and flavodoxin - in 10MAG/LDAO RMs and applying a variety of experimental methods to characterize this system's behavior. We found that this surfactant system differs greatly from the traditional, spherical, monodisperse RM population model. 10MAG/LDAO RMs were discovered to be oblate ellipsoids at all conditions, and as W0 was increased, surfactants redistributed to form a greater number of increasingly spherical ellipsoidal particles with pools of more bulk-like water. Proteins distinctively influence the thermodynamics of the mixture, encapsulating at their optimal RM size and driving protein-free RM sizes to scale accordingly. These findings inform the future development of similarly malleable encapsulation systems and build a foundation for application of 10MAG/LDAO RMs to analyze biological and chemical processes under nanoscale confinement.


Asunto(s)
Glicerol , Micelas , Mioglobina , Tensoactivos , Mioglobina/química , Tensoactivos/química , Glicerol/química , Citocromos c/química , Flavodoxina/química , Lauratos/química , Termodinámica , Agua/química , Dimetilaminas
20.
An Acad Bras Cienc ; 96(2): e20231164, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38747799

RESUMEN

Intensive Care Unit-acquired weakness (ICU-AW) is a common complication that significantly impedes patient recovery. In the study, we investigated the correlation between early serum myoglobin levels in patients with septic shock due to pneumonia, and the incidence of ICU-AW, duration of mechanical ventilation, and prognosis. Patients were classified based on the development of ICU-AW within the first 10 days of ICU admission. We measured serum myoglobin levels upon ICU entry, and analyzed demographic data, APACHE II scores, use of mechanical ventilation, and clinical outcomes, including mortality and duration of mechanical ventilation. The results indicated significantly elevated serum myoglobin levels in the ICU-AW group, correlated with prolonged mechanical ventilation and increased mortality. ROC analysis revealed myoglobin as a promising biomarker for predicting ICU-AW, with an area under the curve of 0.843 (95% CI: 0.819~0.867), demonstrating a sensitivity of 76.00% and specificity of 82.30%. These findings underscored serum myoglobin as a predictive biomarker for early ICU-AW in septic shock patients, highlighting its potential to guide clinical decision-making.


Asunto(s)
Biomarcadores , Unidades de Cuidados Intensivos , Debilidad Muscular , Mioglobina , Choque Séptico , Femenino , Humanos , Masculino , APACHE , Biomarcadores/sangre , Incidencia , Debilidad Muscular/sangre , Mioglobina/sangre , Pronóstico , Respiración Artificial , Curva ROC , Choque Séptico/sangre
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