Effect of two-stage low-temperature tempering process assisted by electrostatic field application on physicochemical and structural properties of myofibrillar protein in frozen longissimus dorsi of tan mutton.

The effects of refrigerator tempering, two-stage low-temperature tempering (TLT), and a combination of TLT with electrostatic field tempering (TLT-1500/2000/2500/3000) on the physicochemical and structural properties of the myofibrillar protein (MPs) in Longissimus dorsi of Tan mutton were investigated. The results from differential scanning calorimetry and dynamic rheology indicated that TLT-2000/2500 had the least impact on the thermal stability of MPs. While the carbonyl and dityrosine contents of MPs in TLT-2000/2500 were the lowest, the total sulfhydryl content and Ca2+-ATPase activity were the highest, suggesting that TLT-2000/2500 preserved the properties of MPs more effectively. The smaller and uniformly distributed particle size, highest zeta potential, and SDS-PAGE analysis confirmed that TLT-2000/2500 had minimal impact on the aggregation and degradation of MPs. Additionally, results from surface hydrophobicity, Fourier transform infrared spectroscopy, intrinsic fluorescence, and UV second-derivative absorption spectra suggested that TLT-2000/2500 was more conducive to stabilizing the primary, secondary, and tertiary structures of MPs.

Effects of umami substances as taste enhancers on salt reduction in meat products: A review.

Sodium is one of the essential additives in meat processing, but excessive sodium intake may increase risk of hypertension and cardiovascular disease. However, reducing salt content while preserving its preservative effect, organoleptic properties, and technological characteristics poses challenges. In this review, the mechanism of salt reduction of umami substances was introduced from the perspective of gustation-taste interaction, and the effects of the addition of traditional umami substances (amino acids, nucleotides, organic acids(OAs)) and natural umami ingredients (mushrooms, seaweeds, tomatoes, soybeans, tea, grains) on the sensory properties of the meat with reduced-salt contents were summarized. In addition, the impacts of taste enhancers on eating quality (color, sensory, textural characteristics, and water-holding capacity (WHC)), and processing quality (lipid oxidation, pH) of meat products (MP) and their related mechanisms were also discussed. Among them, natural umami ingredients exhibit distinct advantages over traditional umami substances in terms of enhancing quality and nutritional value. On the basis of salt reduction, natural umami ingredients improve the flavor, texture, WHC and antioxidant capacity. This comprehensive review may provide the food industry with a theoretical foundation for mitigating salt consumption through the utilization of umami substances and natural ingredients.

Developing active and intelligent biodegradable packaging from food waste and byproducts: A review of sources, properties, film production methods, and their application in food preservation.

Food waste and byproducts (FWBP) are a global issue impacting economies, resources, and health. Recycling and utilizing these wastes, due to processing and economic constraints, face various challenges. However, valuable components in food waste inspire efficient solutions like active intelligent packaging. Though research on this is booming, its material selectivity, effectiveness, and commercial viability require further analysis. This paper categorizes FWBP and explores their potential for producing packaging from both animal and plant perspectives. In addition, the preparation/fabrication methods of these films/coatings have also been summarized comprehensively, focusing on the advantages and disadvantages of these methods and their commercial adaptability. Finally, the functions of these films/coatings and their ultimate performance in protecting food (meat, dairy products, fruits, and vegetables) are also reviewed systematically. FWBP provide a variety of methods for the application of edible films, including being made into coatings, films, and fibers for food preservation, or extracting active substances directly or indirectly from them (in the form of encapsulation) and adding them to packaging to endow them with functions such as barrier, antibacterial, antioxidant, and pH response. In addition, the casting method is the most commonly used method for producing edible films, but more film production methods (extrusion, electrospinning, 3D printing) need to be tried to make up for the shortcomings of the current methods. Finally, researchers need to conduct more in-depth research on various active compounds from FWBP to achieve better application effects and commercial adaptability.

Roles of AhR/CYP1s signaling pathway mediated ROS production in uremic cardiomyopathy.

PURPOSE: Uremic cardiomyopathy (UCM) is the leading cause of chronic kidney disease (CKD) related mortality. Uremic toxins including indoxyl sulfate (IS) play important role during the progression of UCM. This study was to explore the underlying mechanism of IS related myocardial injury. METHODS: UCM rat model was established through five-sixths nephrectomy to evaluate its effects on blood pressure, cardiac impairment, and histological changes using echocardiography and histological analysis. Additionally, IS was administered to neonatal rat cardiomyocytes (NRCMs) and the human cardiomyocyte cell line AC16. DHE staining and peroxide-sensitive dye 2',7'-dichlorofluorescein diacetate (H2DCFDA) was conducted to assess the reactive oxygen species (ROS) production. Cardiomyocyte hypertrophy was estimated using wheat germ agglutinin (WGA) staining and immunofluorescence. Aryl hydrocarbon receptor (AhR) translocation was observed by immunofluorescence. The activation of AhR was evaluated by immunoblotting of cytochrome P450 1 s (CYP1s) and quantitative real-time PCR (RT-PCR) analysis of AHRR and PTGS2. Additionally, the pro-oxidative and pro-hypertrophic effects were evaluated using the AhR inhibitor CH-223191, the CYP1s inhibitor Alizarin and the ROS scavenger N-Acetylcysteine (NAC). RESULTS: UCM rat model was successfully established, and cardiac hypertrophy, accompanied by increased blood pressure, and myocardial fibrosis. Further research confirmed the activation of the AhR pathway in UCM rats including AhR translocation and downstream protein CYP1s expression, accompanied with increasing ROS production detected by DHE staining. In vitro experiment demonstrated a translocation of AhR triggered by IS, leading to significant increase of downstream gene expression. Subsequently study indicated a close relationship between the production of ROS and the activation of AhR/CYP1s, which was effectively blocked by applying AhR inhibitor, CYP1s inhibitor and siRNA against AhR. Moreover, the inhibition of AhR/CYP1s/ROS pathway collectively blocked the pro-hypertrophic effect of IS-mediated cardiomyopathy. CONCLUSION: This study provides evidence that the AhR/CYP1s pathway is activated in UCM rats, and this activation is correlated with the uremic toxin IS. In vitro studies indicate that IS can stimulate the AhR translocation in cardiomyocyte, triggering to the production of intracellular ROS via CYP1s. This process leads to prolonged oxidative stress stimulation and thus contributes to the progression of uremic toxin-mediated cardiomyopathy.

Lipoprotein-associated phospholipase A2 predicts cardiovascular death in patients on maintenance hemodialysis: a 7-year prospective cohort study.

BACKGROUND: Cardiovascular diseases (CVD) is the leading cause of death among maintenance hemodialysis patients, with dyslipidemia being a prevalent complication. The paradoxical relationship between cardiovascular outcomes and established lipid risk markers, such as low-density lipoprotein cholesterol (LDL-C), complicates lipid management in this population. This study investigated Lipoprotein-associated phospholipase A2 (Lp-PLA2), an emerging biomarker known for its proinflammatory and proatherogenic properties, as a potential cardiovascular prognostic marker in this cohort. In this context, the association between Lp-PLA2 levels and cardiovascular outcomes was evaluated, with the aim to facilitate more accurate stratification and identification of high-risk individuals. METHODS: From August 2013 to January 2014, 361 hemodialysis patients were prospectively enrolled. Lp-PLA2 activity and laboratory measures at baseline were quantified. Comorbidities and medications were recorded. All patients were followed until the end of April, 2022. The individual and combined effects of Lp-PLA2 activity and LDL-C on patient outcomes were examined. The association between Lp-PLA2 activity and all-cause mortality, cardiovascular mortality, and major adverse cardiovascular events (MACEs) was analyzed. RESULTS: The median Lp-PLA2 activity was 481.2 U/L. In subjects with Lp-PLA2 activity over 481.2 U/L, significantly higher total cholesterol (4.89 vs. 3.98 mmol/L; P < 0.001), LDL-C (3.06 vs. 2.22 mmol/L; P < 0.001), and apolipoprotein B (0.95 vs. 0.75 mmol/L; P < 0.001) were observed. Over a median follow-up of 78.1 months, 182 patients died, with 77 cases identified as cardiovascular death, 88 MACEs happened. Cardiovascular mortality and MACEs, but not all-cause mortality, were significantly increased in the high Lp-PLA2 group. Cox regression analyses showed that high Lp-PLA2 activity was associated with cardiovascular mortality and MACE occurrence. After comprehensive adjustment, high Lp-PLA2 activity was independently associated with cardiovascular mortality(as a dichotomous variable: HR:2.57, 95%CI:1.58,4.18, P < 0.001; as a continuous variable: HR:1.25, 95%CI:1.10,1.41, P = 0.001) and MACEs(as a dichotomous variable: HR:2.17, 95%CI:1.39,3.40, P = 0.001; as a continuous variable: HR:1.20, 95%CI:1.07,1.36, P = 0.002). When participants were grouped by median Lp-PLA2 activity and LDL-C values, those with high Lp-PLA2 and low LDL-C had the highest CV mortality. The addition of Lp-PLA2 significantly improved reclassification (as a dichotomous variable NRI = 42.51%, 95%CI: 5.0%,61.33%; as a continuous variable, NRI = 33.32%, 95% CI: 7.47%,56.21%). CONCLUSIONS: High Lp-PLA2 activity is an independent risk factor for cardiovascular mortality and MACEs occurrence in patients on hemodialysis. The combined measures of Lp-PLA2 and LDL-C help to identify individuals with a higher risk of cardiovascular death.

Weekend effect on the incidence and outcomes of cardiac surgery associated - acute kidney injury.

BACKGROUND: The effects of surgical day (workdays or weekends) on occurrence and outcome of cardiac surgery associated -acute kidney injury (CSA-AKI) remains unclear. This study aimed to compare the incidence and short-term outcomes of CSA-AKI in patients undergoing surgery on workdays and weekends. MATERIALS AND METHODS: Patients who underwent cardiac surgery from July 2020 to December 2020 were retrospectively enrolled in this study. These patients were divided into a weekend group and workday group. The primary endpoint was the incidence of CSA-AKI. The secondary endpoints included renal function recovery and in-hospital mortality. The logistic regression model was used to explore the risk factors for CSA-AKI. Stratification analysis was performed to estimate the association between CSA-AKI and weekend surgery stratified by emergency surgery. RESULTS: A total of 1974 patients undergoing cardiac surgery were enrolled. The incidence of CSA-AKI in the weekend group was significantly higher than that in the workday group (42.8% vs. 34.7%, P = 0.038). Further analysis of patients with CSA-AKI showed that there was no difference in renal function recovery between the workday AKI group and weekend AKI group. There was no difference in in-hospital mortality between the weekend group and workday group (3.6% vs. 2.4%, P = 0.327); however, the in-hospital mortality of the weekend AKI group was significantly higher than that of the workday AKI group (8.5% vs. 2.9%, P = 0.014). Weekend surgery and emergency surgery were independent risk factors for CSA-AKI. The multiplicative model showed an interaction between weekend surgery and emergency surgery; weekend surgery was related to an increased risk of AKI among patients undergoing emergency surgery [adjusted OR (95% CI): 1.96 (1.012-8.128)]. CONCLUSIONS: The incidence of CSA-AKI in patients undergoing cardiac surgery on weekends was significantly higher compared to that in patients undergoing cardiac surgery on workdays. Weekend surgery did not affect the in-hospital mortality of all patients but significantly increased the mortality of AKI patients. Weekend surgery and emergency surgery were independent risk factors for CSA-AKI. Weekend emergency surgery significantly increased the risk of CSA-AKI.

Development and characterization of a new potato starch/watermelon peel pectin composite film loaded with TiO2 nanoparticles and microencapsulated Lycium barbarum leaf flavonoids and its use in the Tan mutton packaging.

Reinforced edible film with active nanoparticles has been in increasing demand as a new technology to improve the quality and extend the shelf-life of muscle foods. The study aimed to fabricate and characterize a novel potato starch (Pst)/watermelon peel pectin (Wpp) composite film with the microencapsulated Lycium barbarum leaf flavonoids (MLF) and nano-TiO2 (Pst/Wpp/MLF/TiO2) and further apply the film in Tan mutton preservation. The moisture content, thickness and water vapor permeability (WVP) of the composite film were relatively increased with increasing the percentage of MLF, while nano-TiO2 had slight influence on the thickness, but leaded to a significantly decreased the moisture content and WVP. Also, the SEM images showed that the roughness and porosity were created on the film surface by adding MLF and nano-TiO2. FTIR revealed electrostatic and hydrogen bond interactions between the components in the film system. Meanwhile, MLF and nano-TiO2 effectively enhanced the mechanical strength, UV-barrier, controlled-release, thermal stability, antimicrobial and antioxidation properties of the Pst/Wpp film. Also, the composite film containing MLF and nano-TiO2 significantly inhibited the growth of microorganisms and chemical deterioration of mutton samples, which suggested that such film has potential as a prospective active packaging for preserving Tan mutton.

Physicochemical and structural changes of myofibrillar proteins in muscle foods during thawing: Occurrence, consequences, evidence, and implications.

Myofibrillar protein (MP) endows muscle foods with texture and important functional properties, such as water-holding capacity (WHC) and emulsifying and gel-forming abilities. However, thawing deteriorates the physicochemical and structural properties of MPs, significantly affecting the WHC, texture, flavor, and nutritional value of muscle foods. Thawing-induced physicochemical and structural changes in MPs need further investigation and consideration in the scientific development of muscle foods. In this study, we reviewed the literature for the thawing effects on the physicochemical and structural characters of MPs to identify potential associations between MPs and the quality of muscle-based foods. Physicochemical and structural changes of MPs in muscle foods occur because of physical changes during thawing and microenvironmental changes, including heat transfer and phase transformation, moisture activation and migration, microbial activation, and alterations in pH and ionic strength. These changes are not only essential inducements for changes in spatial conformation, surface hydrophobicity, solubility, Ca2+ -ATPase activity, intermolecular interaction, gel properties, and emulsifying properties of MPs but also factors causing MP oxidation, characterized by thiols, carbonyl compounds, free amino groups, dityrosine content, cross-linking, and MP aggregates. Additionally, the WHC, texture, flavor, and nutritional value of muscle foods are closely related to MPs. This review encourages additional work to explore the potential of tempering techniques, as well as the synergistic effects of traditional and innovative thawing technologies, in reducing the oxidation and denaturation of MPs and maintaining the quality of muscle foods.

Effect of angiography timing on acute kidney injury after cardiac surgery in patients with preoperative renal dysfunction.

BACKGROUND: Cardiac surgery-associated acute kidney injury (AKI) is one of the common complications of cardiac surgery. Preoperative angiography helps assess heart disease but may increase the risk of AKI. Although more and more patients with preoperative renal dysfunction can undergo cardiac surgery with the advances in surgical techniques, there is little research on the effect of angiography on postoperative AKI in these patients. This study investigates whether angiography increases the risk of AKI after cardiac surgery in patients with preoperative renal dysfunction (15 ≤ eGFR < 60 ml/min/1.73m2). METHODS: Patients with preoperative renal dysfunction (15 ≤ eGFR < 60 ml/min/1.73m2) who underwent angiography and cardiac surgery successively from January 2015 to December 2020 were retrospectively enrolled in this study. The primary outcome was postoperative AKI, defined as the Kidney Disease: Improving Global Outcomes Definition and Staging (KDIGO) criteria. Univariate analysis and multivariate regression were performed to identify the association between angiography timing and AKI. RESULTS: A total of 888 consecutive eligible patients with preoperative renal dysfunction (15 ≤ eGFR < 60 ml/min/1.73m2) were enrolled in this study. The incidence of AKI was 48.31%. Male (OR = 1.903), the interval between angiography and surgery (0-2d OR = 2.161; 3-6d OR = 3.291), cross-clamp duration (OR = 1.009), were identified as predictors for AKI. The interval between angiography and surgery was also associated with AKI in the patients with 15 ≤ eGFR < 30ml/min/1.73m2 (0-2d OR = 4.826; 3-6d OR = 5.252), 30 ≤ eGFR < 45 ml/min/1.73m2 (0-2d OR = 2.952; 3-6d OR = 3.677), but not associated with AKI in patients with 45 ≤ eGFR < 60 ml/min/1.73m2. CONCLUSIONS: In patients with preoperative renal dysfunction, the interval between angiography and cardiac surgery (0-2d and 3-6d) was associated with AKI. For patients with poorer preoperative renal function, the interval between angiography and cardiac surgery is of great concern.

Active edible films with plant extracts: a updated review of their types, preparations, reinforcing properties, and applications in muscle foods packaging and preservation.

Currently, edible films have been increasingly explored to solve muscle food spoilage during storage, especially through the incorporation of plant extracts to develop edible packaging materials. Natural polymers matrices with plant extracts are befitting for fabricating edible films by casting methods. In the films system, the structure and physicochemical properties were strengthened via chemical interactions between active molecules in plant extracts and the reactive groups in the polymer chain. The antibacterial and antioxidant properties were dramatically reinforced through both physical and chemical actions of the plant extracts. Additionally, edible films imbedded with color-rich plant extracts could be considered as potential sensitive indicators to monitor the spoilage degree of muscle foods in response to change in gas or temperature. Furthermore, these films could increase sensory acceptability, improve quality and prolong the shelf life of muscle foods. In this article, the types, preparation methods and reinforcing properties of the edible films with plant extracts were discussed. Also, the applications of these films were summarized on quality maintenance and shelf-life extension and intelligent monitoring in muscle foods. Finally, a novel technology for film preparation achieving high-stability and sustained release of active compounds will become an underlying trend for application in muscle food packaging.

A comprehensive review of the principles, key factors, application, and assessment of thawing technologies for muscle foods.

For years, various thawing technologies based on pressure, ultrasound, electromagnetic energy, and electric field energy have been actively investigated to minimize the amount of drip and reduce the quality deterioration of muscle foods during thawing. However, existing thawing technologies have limitations in practical applications due to their high costs and technical defects. Therefore, key factors of thawing technologies must be comprehensively analyzed, and their effects must be systematically evaluated by the quality indexes of muscle foods. In this review, the principles and key factors of thawing techniques are discussed, with an emphasis on combinations of thawing technologies. Furthermore, the application effects of thawing technologies in muscle foods are systematically evaluated from the viewpoints of eating quality and microbial and chemical stability. Finally, the disadvantages of the existing thawing technologies and the development prospects of tempering technologies are highlighted. This review can be highly instrumental in achieving more ideal thawing goals.

Edible films/coatings containing bioactive ingredients with micro/nano encapsulation: A comprehensive review of their fabrications, formulas, multifunctionality and applications in food packaging.

Due to the consumer's pursuit of safe, nontoxic and nutritious foods, edible and/or biodegradable materials have stood out in food packaging and preservation. In this context, the preparation and application of micro/nano encapsulated active ingredients (M/N-E-BAIs) represent a step toward reinforcing the properties of sustainable and controllable food packaging, particularly for the successful incorporation of new substances and functionalities into traditional edible films/coatings. This review, from the preparation of M/N-E-BAIs, the fabrication of edible film/coating containing M/N-E-BAIs to their characterization of multifunction and the application in food, makes a systematic summary and in-depth discussion. Food-grade polymers can encapsulate bioactive ingredients (BAIs) by chemical, physicochemical and mechanical methods, thereby forming M/N-E-BAIs with suitable sustained-release and unique biological activities. Furthermore, M/N-E-BAIs is incorporated into biopolymer substrates by solvent casting, 3D printing or electrostatic spinning to obtain novel edible films/coatings. This advanced packaging material exhibits superior physicochemical and functional properties over traditional food films/coatings. Besides, their applications in foods as active and intelligent packaging can improve food quality, prolong shelf life and monitor food corruption. Even so, there are still many challenges and limitations in formulation, preparation and application of this new packaging technology that need to be addressed in the future.

Development of surface-enhanced Raman spectroscopy application for determination of illicit drugs: Towards a practical sensor.

Surface-enhanced Raman spectroscopy (SERS) has been widely applied to identify or detect illicit drugs, because of the ability for highly specific molecular fingerprint and independence of aqueous solutions impact. We summarize the progress in determination of illicit drugs using SERS, including trace illicit drugs, suspicious objects and drugs or their metabolites in real biological system (urine, saliva and so on). Even though SERS detection of illicit drugs in real samples still remains a huge challenge because of the complex unknown environment, the efficient sample separation and the improved hand-held Raman analyzer will provide the possibility to make SERS a practically analytical technique. Moreover, we put forward a prospective overview for future perspectives of SERS as a practical sensor for illicit drugs determination. Perhaps the review is not exhaustive, we expect to help researchers to understand the evolution and challenges in this field and further interest in promoting Raman and SERS as a practical analyzer for convenient and automated illicit drugs identification.

Sensitive and simple determination of zwitterionic morphine in human urine based on liquid-liquid micro-extraction coupled with surface-enhanced Raman spectroscopy.

Morphine, a kind of illicit drugs, is also one of the main heroin metabolites. In consideration of a noninvasive way to monitor and identify drug abuse during forensic cases, the urine samples are usually detected. Here, colloidal gold nanorods (Au NRs) were introduced to act as active substrate, because of the strong optical extinction and spectral tunability of the longitudinal surface plasmon resonance (SPR). Thus, well surface-enhanced Raman spectra of morphine even at low concentrations could be obtained by portable Raman spectrometer. For the complex matrix environment of urine, liquid-liquid micro-extraction (LLME), a simple and inexpensive pretreatment, was employed to avoid the interferences. And then, the coupled surface-enhanced Raman spectroscopy (SERS) can give full play to the advantages of high sensitivity and unique spectroscopic fingerprint. According to the zwitterionic structure and physicochemical parameters of morphine molecules, the pH value of urine sample was adjusted to about 9 by buffer solution (KOH/NaB4O7) and the mixture of chloroform and isopropyl alcohol (V/V=9:1) was chosen as extractant. Moreover, such pretreatment was proved to be appropriate for separation and concentration of morphine from urine. The developed LLME-SERS method could provide a detection limit less than 1 ppm in the human urine environment and the whole process of detection just needed take 5-6 min. What's more, the results of urine samples from heroin users exhibited application value of the proposed technique. The excellent performance makes it promising to become a rapid, reliable, and on-spot analyzer, especially for public safety and healthcare.

Designing of ordered two-dimensional gold nanoparticles film for cocaine detection in human urine using surface-enhanced Raman spectroscopy.

A novel and rapid method to detect cocaine in human urine has been developed by using self-assembly ordered two dimensional (2D) gold nanoparticles (GNPs) film as surface-enhanced Raman spectroscopy (SERS) substrates. In order to obtain high sensitivity, uniformity, and reproducibility of SERS platform, quasi-spherical, uniform GNPs were firstly synthesis using seed growth method, in which the GNPs have been functionalized with CTAB to form orderly close-packed GNPs film as SERS substrate. Importantly, the high-performance GNPs on solid substrates can produce a high yield of sub-10-nm gaps which can generate gigantic signals enhancement for analytes adsorbed GNPs surface. In view of the complex component of human urine, we develop a rapid and efficient pretreatment strategy for separation and purification of cocaine by using hexane extraction in real human urine samples within 3min. With the advantages of better extraction rates (>75%) examined by ultraperformance liquid chromatography (UPLC) and the excellent signal-to-noise ratio detected by SERS, our pretreatment procedure can efficiently lower the interference of complex biological components in urine. To reach on-spot analyzer, a handheld Raman spectrometer was used for feasible SERS detection of cocaine in real human urine. The favorable results demonstrated our pretreatment strategy combined with SERS platform will be a great prospective method toward rapid, reliable, and on-spot cocaine detection for public safety.