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Abstract High thermal conductivity aluminium-based silicon carbide (Al/SiC) composites were successfully fabricated through post-oxidization of reaction-bonded silicon carbide preforms (RS preforms), utilizing vacuum pressure infiltration technology. The study investigated the regulation of interfacial reactions in conventional sintering and reaction sintering. Conventional sintering introduced a large amount of SiO2, which negatively impacted the thermal conductivity of the Al/SiC composite, but the reaction sintering not. The proposed post-oxidization treatment of RS preforms effectively removed residual carbon from the SiC particle surfaces, thereby forestalling the formation of Al4C3. Furthermore, the post-oxidization treatment effectively formed lightweight SiO2 deposits onto the surface of SiC particles, improving Al-SiC interfacial wettability and reducing thermal resistance, thereby enhancing composite thermal conductivity. Notably, the thermal conductivity of the post-oxidized sample exhibited an increase of 6.5% compared to the untreated sample. The study also evaluated the impact of particle size distribution on volume fraction and thermal properties. The optimized Al/SiC composites yielded thermal conductivity, coefficient of thermal expansion, bending strength, and Young’s modulus values of 237.3 W/m K, 8.5 × 10−6/°C, 325 MPa, and 75.9 GPa, respectively.

BackgroundCoronary obstruction (CO) is a rare but devasting complication during transcatheter aortic valve replacement (TAVR).ObjectivesWe aim to demonstrate that the predicted distance between the coronary ostia and the closest structure derived with patient-specific computer simulation is associated with CO risk during TAVR.MethodsWe retrospectively analysed 14 aortic stenosis patients who underwent TAVR through finite element simulation. The frame deformation predicted with patient-specific computer simulation was qualitatively and quantitatively compared to the post-operative device deformation. The minimum distance between each coronary ostium and the closest structure was calculated and compared in patients who developed CO, at high risk of CO, and at no risk of CO.ResultsFour patients experienced CO during TAVR, 5 patients were at high risk of CO, and the remaining 5 patients had no risk of CO. A high coefficient of determination was obtained for all measurements extracted from the simulated device and the post-operative device (≥0.95). Simulations predicted shorter distance between the coronary ostium and the closest structure in patients who experienced CO, compared to patients at high risk of CO or who did not experience this complication (right coronary: 5.9 vs. 6.8 vs. 8.8 mm, left coronary: 3.0 vs. 3.3 vs. 6.5 mm respectively).ConclusionsThe distance between the coronary ostium and the closest structure was lower in patients who experienced CO during TAVR through patient-specific computational simulation. This technology enables coronary obstruction analysis before TAVR in the future.

Abstract 3D printing of liquid metal remains a big challenge due to its low viscosity and large surface tension. In this study, we use Carbopol hydrogel and liquid gallium-indium alloy to prepare a liquid metal high internal phase emulsion gel ink, which can be used for direct-ink-writing 3D printing. The high volume fraction (up to 82.5%) of the liquid metal dispersed phase gives the ink excellent elastic properties, while the Carbopol hydrogel, as the continuous phase, provides lubrication for the liquid metal droplets, ensuring smooth flow of the ink during shear extrusion. These enable high-resolution and shape-stable 3D printing of three-dimensional structures. Moreover, the liquid metal droplets exhibit an electrocapillary phenomenon in the Carbopol hydrogel, which allows for demulsification by an electric field and enables electrical connectivity between droplets. We have also achieved the printing of ink on flexible, non-planar structures, and demonstrated the potential for alternating printing with various materials.

BackgroundThere are limited data available on the development of arrhythmias in patients at risk of high-degree atrioventricular block (HAVB) or complete heart block (CHB) following transcatheter aortic valve replacement (TAVR). ObjectiveThis study aimed to explore the incidence and evolution of arrhythmias by monitoring patients at risk of HAVB or CHB after TAVR using smartwatches. MethodsWe analyzed 188 consecutive patients in the prospective SMART TAVR (smartwatch-facilitated early discharge in patients undergoing TAVR) trial. Patients were divided into 2 groups according to the risk of HAVB or CHB. Patients were required to trigger a single-lead electrocardiogram (ECG) recording and send it to the Heart Health App via their smartphone. Physicians in the central ECG core lab would then analyze the ECG. The incidence and timing of arrhythmias and pacemaker implantation within a 30-day follow-up were compared. All arrhythmic events were adjudicated in a central ECG core lab. ResultsThe mean age of the patients was 73.1 (SD 7.3) years, of whom 105 (55.9%) were men. The mean discharge day after TAVR was 2.0 (SD 1.8) days. There were no statistically significant changes in the evolution of atrial fibrillation or atrial flutter, Mobitz I, Mobitz II, and third-degree atrial ventricular block over time in the first month after TAVR. The incidence of the left bundle branch block (LBBB) increased in the first week and decreased in the subsequent 3 weeks significantly (P

Unsaturated aliphatic aldehyde oxidation plays a significant role in the deep oxidation of fatty acids to produce volatile chemicals. Exposing the oxidation process of unsaturated aliphatic aldehydes is crucial to completely comprehend how food flavor forms. In this study, thermal desorption cryo-trapping in conjunction with gas chromatography-mass spectrometry was used to examine the volatile profile of (E)-4-decenal during heating, and 32 volatile compounds in all were detected and identified. Meanwhile, density functional theory (DFT) calculations were used, and 43 reactions were obtained in the 24 pathways, which were summarized into the peroxide reaction mechanism (ROOH), the peroxyl radical reaction mechanism (ROO·) and the alkoxy radical reaction mechanism (RO·). Moreover, the priority of these three oxidative mechanisms was the RO· mechanism > ROOH mechanism > ROO· mechanism. Furthermore, the DFT results and experimental results agreed well, and the oxidative mechanism of (E)-4-decenal was finally illuminated.

Strong-flavor Daqu, as a fermentation agent, plays a significant role in shaping the quality of strong-flavor baijius, and fungal species in Daqu are important factors affecting the quality of Daqu. Therefore, we selected strong-flavor Daqu from seven different origins to study the fungal composition and the effects of the fungal composition on the physicochemical properties and volatile organic compounds (VOCs). It was found that the fungal composition influences the physicochemical properties of Daqu. Specifically, there was a positive link between Rhizomucor, Rhizopus, Thermomyces, and liquefying activity and a positive correlation between Aspergillus and fermenting activity. Furthermore, the relationships between esterifying activity and Thermomyces, Rhizomucor, Aspergillus, Pichia, and Saccharomycopsis were found to be positive. The VOCs in Daqu were affected by Aspergillus, Issatchenkia, Pichia, and Thermoascus. Issatchenkia was significantly positively correlated with benzeneethanol as well as Aspergillus and pentadecanoic acid ethyl ester, ethyl myristate. Pichia and Thermoascus were significantly negatively correlated with benzaldehyde and 2-furaldehyde. This study deepens our understanding of the relationship between VOCs, the physicochemical properties with microbial communities, and reference significance for the production of better-quality strong-flavor Daqu.

Oleic acid oxidation is one of the main sources of food flavor compounds. Volatile profiling was investigated using thermal desorption cryo-trapping combined with gas chromatography–mass spectrometry to analyze the volatile composition of oleic acid oxidation. A total of 43 volatile compounds, including aldehydes (11), ketones (2), alcohols (5), furans (2), acids (8), ester (12) and alkane (3) were identified from oleic acid during heating. Then, density functional theory (DFT) was applied to analyze the oxidative mechanism of oleic acid during heating. A total of 30 reactions were obtained and grouped into the peroxide (ROOH), alkoxy radical (RO•), and peroxide radical (ROO•) pathways. The structures of intermediates, transition states (TS), and products in each reaction were also determined. Results show that the branch chemical reactions were the key reactions in different reaction pathway. Moreover, the reaction priority of the thermal oxidation reaction of oleic acid was the peroxide radical mechanism > the peroxide mechanism > the alkoxy radical mechanism.

This research endeavored to elucidate the antioxidant attributes of lactic acid bacteria, specifically their impact on anti-aging and lifespan augmentation in Caenorhabditis elegans. The study focused on Lactiplantibacillus plantarum A72, identified through ARTP mutagenesis for its potent antioxidant properties. In vitro analysis affirmed its free radical neutralizing capacity. In C. elegans, the strain not only extended the lifespan by 25.13% and amplified motility 2.52-fold, but also maintained reproductive capabilities. Remarkably, Lpb. plantarum A72 diminished reactive oxygen species (ROS) and malondialdehyde (MDA) levels in C. elegans by 34.86% and 69.52%, respectively, while concurrently enhancing its antioxidant enzyme activities. The strain also bolstered C. elegans survival rates by 46.33% and 57.78% under high temperature and H2O2 conditions, respectively. Transcriptomic scrutiny revealed that Lpb. plantarum A72 could retard C. elegans aging and extend lifespan by upregulating the sod-5 and hsp-16.1 genes and downregulating the fat-6 and lips-17 genes. These findings propose Lpb. plantarum A72 as a potential antioxidant and anti-aging lactic acid bacteria.

It has been proposed that the proportions of the human face are crucial for facial aesthetics. If this is the case, we should describe the relationship among proportions of face components quantitatively. This study aims to develop a mathematical model of facial proportions to provide a quantitative description of facial attractiveness. Furthermore, we expect that plastic surgeons can use models in clinical work to enhance communication efficiency between doctors and patients. Face alignment technique was used to analyse 5500 frontal faces with diverse properties (male/female, Asian/Caucasian, ages) to obtain the ratios among the nose length ($ {N}_{L} $), the nasal base width ($ N $), and the inner canthus width ($ {E}_{I} $). A mathematical model ($ {N}_{L}^{2} = a{E}_{I}\mathrm{*}{N}_{L}+b{E}_{I}\mathrm{*}N+cN\mathrm{*}{N}_{L} $) was developed to describe the relationship among these proportions. To validate the effectiveness of this approach, we simulated the post-operative photos using Adobe Photoshop. Our findings show that the ratio of nose length to nose width, the ratio of inner canthus width to nose length and the ratio of inner canthus to nose width play a significant role in determining facial attractiveness. These results provide a possible strategy to quantitatively describe the relationship among human face proportions.

BackgroundThere are only limited reports on the trends of NT-proBNP after transcatheter aortic valve replacement (TAVR) in aortic stenosis (AS) and even fewer report on the prognostic value of the NT-proBNP trajectory following TAVR.ObjectivesThis study aims to investigate short-term NT-proBNP trajectory following TAVR and explore its association with clinical outcomes in TAVR recipients.MethodsAortic stenosis patients undergoing TAVR were included if they had NT-proBNP levels recorded at baseline, prior to discharge, and within 30 days after TAVR. We used latent class trajectory models to identify NT-proBNP trajectories based on their trends over time.ResultsThree distinct NT-proBNP trajectories were identified from 798 TAVR recipients, which were named class 1 (N = 661), class 2 (N = 102), and class 3 (N = 35). Compared to those with trajectory class 1, patients with trajectory class 2 had a more than 2.3-fold risk of 5-year all-cause death and 3.4-fold risk of cardiac death, while patients with trajectory class 3 had a more than 6.6-fold risk of all-cause death and 8.8-fold risk of cardiac death. By contrast, the groups had no differences in 5-year hospitalization rates. In multivariable analyses, the risk of 5-year all-cause mortality was significantly higher in patients with trajectory class 2 (HR 1.90, 95% CI 1.03–3.52, P = 0.04) and class 3 (HR 5.70, 95% CI 2.45–13.23, P < 0.01).ConclusionOur findings implied different short-term evolution of NT-proBNP levels in TAVR recipients and its prognostic value for AS patients following TAVR. NT-proBNP trajectory may have further prognostic value, in addition to its baseline level. This may aid clinicians with regards to patient selection and risk prediction in TAVR recipients.

Background: Decreased length of stay in the index hospitalization is a tendency in transcatheter aortic valve replacement (TAVR) era. In this study, we aim to evaluate the feasibility and safety of next-day discharge (NDD) in bicuspid aortic valve (BAV) patients following TAVR. Methods: The study analyzed patients who received TAVR in 2019 to 2022. Thirty-day mortality and readmission rate were compared between BAV and tricuspid aortic valve (TAV) patients. Results: The proportion of NDD was similar between the BAV and TAV group (45.3 % vs 41.3 %, p = 0.487). In NDD patients, the lower age (72.0 [67.0, 77.0] yrs vs 74.0 [70.0, 80.0] yrs, p = 0.011) and STS score (2.33 [1.56, 3.54] % vs 3.82 [2.38, 5.70] %, p

Cider flavor has a very important impact on the quality. Solid-phase microextraction-gas chromatography–mass spectrometry (SPME-GC-MS) combined with gas chromatography–ion mobility spectrometry (GC-IMS) tested different kinds of non-Saccharomyces yeasts and Saccharomyces cerevisiae (S. cerevisiae) co-inoculated for the fermentation of cider to determine differences in aroma material, and the determination of odor activity value (OAV) is applied less frequently in research. Through Rhodotorula mucilaginosa, Debaryomyces hansenii, Zygosaccharomyces bailii, and Kluyveromyces Marxianus, four different strains of non-Saccharomyces yeast fermented cider, and it was found that, in both the chemical composition and flavor of material things, compared with monoculture-fermented cider using S. cerevisiae, all differences were significant. Co-inoculated fermentation significantly improved the flavor and taste of cider. As in the volatile compounds of OVA > 1, octanoic acid (Sc 633.88 μg/L, co-inoculation fermented group 955.49 μg/L) provides vegetable cheese fragrance and decanoic acid, ethyl ester (Sc 683.19 μg/L, co-inoculation fermented group 694.98 μg/L) a creamy fruity fragrance, etc., and the average content increased after co-inoculated fermentation. Phenylethyl alcohol, which can produce a rose scent, was relatively abundant in cider samples and varied greatly among the groups. Moreover, the contents of ethyl lactate and 1-butanol in the Sc+Rm (ciders fermented by S. cerevisiae and R. mucilaginosa) were the highest of all of the cider samples. Different types of non-Saccharomyces yeast produced cider with different flavor characteristics. This study demonstrates that different species of non-Saccharomyces yeast do have an important impact on the characteristics of cider and that co-inoculation with non-Saccharomyces yeast and S. cerevisiae for cider fermentation may be a strategy to improve the flavor of cider.

Morganella morganii, a spoilage bacterium in fermented foods, produces harmful biogenic amines (BAs). Although Lactiplantibacillus plantarum is widely used to inhibit spoilage bacteria, the inhibition pattern and inhibition mechanism of M. morganii by Lpb. plantarum are not well studied. In this study, we analysed the effects of the addition of Lpb. plantarum cell-free supernatant (CFS) on the growth and BA accumulation of M. morganii and revealed the mechanisms of changes in different BAs by using RNA sequencing transcriptome analysis. The results showed that Lpb. plantarum CFS could significantly inhibit M. morganii BAs in a weak acid environment (pH 6), and the main changes were related to metabolism. Carbohydrate and energy metabolism were significantly down-regulated, indicating that Lpb. plantarum CFS inhibited the growth activity and decreased the BA content of M. morganii. In addition, the change in histamine content is also related to the metabolism of its precursor amino acids, the change in putrescine content may also be related to the decrease in precursor amino acid synthesis and amino acid transporter, and the decrease in cadaverine content may also be related to the decrease in the cadaverine transporter. The results of this study help to inhibit the accumulation of harmful metabolites in fermented foods.

Ethyl carbamate (EC), a 2A carcinogen produced during the fermentation of foods and beverages, primarily occurs in distilled spirits. Currently, most studies focus on strategies for EC mitigation. In the present research, we aimed to screen strains that can degrade EC directly. Here, we report two Candida ethanolica strains (J1 and J116), isolated from fermented grains, which can reduce EC concentrations directly. These two yeasts were grown using EC as the sole carbon source, and they grew well on different carbon sources. Notably, after immobilization with chitosan, the two strains degraded EC in Chinese Baijiu by 42.27% and 27.91% in 24 h (from 253.03 ± 9.89 to 146.07 ± 1.67 and 182.42 ± 5.05 μg/L, respectively), which was better than the performance of the non-immobilized strains. Furthermore, the volatile organic compound content, investigated using gas chromatography-mass spectrometry, did not affect the main flavor substances in Chinese Baijiu. Thus, the yeasts J1 and J116 may be potentially used for the treatment and commercialization of Chinese Baijiu.

Background and purposeFutile recanalization occurs when the endovascular thrombectomy (EVT) is a technical success but fails to achieve a favorable outcome. This study aimed to use machine learning (ML) algorithms to develop a pre-EVT model and a post-EVT model to predict the risk of futile recanalization and to provide meaningful insights to assess the prognostic factors associated with futile recanalization.MethodsConsecutive acute ischemic stroke patients with large vessel occlusion (LVO) undergoing EVT at the National Advanced Stroke Center of Nanjing First Hospital (China) between April 2017 and May 2021 were analyzed. The baseline characteristics and peri-interventional characteristics were assessed using four ML algorithms. The predictive performance was evaluated by the area under curve (AUC) of receiver operating characteristic and calibration curve. In addition, the SHapley Additive exPlanations (SHAP) approach and partial dependence plot were introduced to understand the relative importance and the influence of a single feature.ResultsA total of 312 patients were included in this study. Of the four ML models that include baseline characteristics, the “Early” XGBoost had a better performance {AUC, 0.790 [95% confidence intervals (CI), 0.677–0.903]; Brier, 0.191}. Subsequent inclusion of peri-interventional characteristics into the “Early” XGBoost showed that the “Late” XGBoost performed better [AUC, 0.910 (95% CI, 0.837–0.984); Brier, 0.123]. NIHSS after 24 h, age, groin to recanalization, and the number of passages were the critical prognostic factors associated with futile recanalization, and the SHAP approach shows that NIHSS after 24 h ranks first in relative importance.ConclusionsThe “Early” XGBoost and the “Late” XGBoost allowed us to predict futile recanalization before and after EVT accurately. Our study suggests that including peri-interventional characteristics may lead to superior predictive performance compared to a model based on baseline characteristics only. In addition, NIHSS after 24 h was the most important prognostic factor for futile recanalization.

Background and purposeFutile recanalization occurs in a significant proportion of patients with basilar artery occlusion (BAO) after endovascular thrombectomy (EVT). Therefore, our goal was to develop a visualized nomogram model to early identify patients with BAO who would be at high risk of futile recanalization, more importantly, to aid neurologists in selecting the most appropriate candidates for EVT.MethodsPatients with BAO with EVT and the Thrombolysis in Cerebral Infarction score of ≥2b were included in the National Advanced Stroke Center of Nanjing First Hospital (China) from October 2016 to June 2021. The exclusion criteria were lacking the 3-month Modified Rankin Scale (mRS), age 2, and unavailable baseline CT imaging. Potential predictors were selected for the construction of the nomogram model and the predictive and calibration capabilities of the model were assessed.ResultsA total of 84 patients with BAO were finally enrolled in this study, and patients with futile recanalization accounted for 50.0% (42). The area under the curve (AUC) of the nomogram model was 0.866 (95% CI, 0.786–0.946). The mean squared error, an indicator of the calibration ability of our prediction model, was 0.025. A web-based nomogram model for broader and easier access by clinicians is available online at https://trend.shinyapps.io/DynNomapp/.ConclusionWe constructed a visualized nomogram model to accurately and online predict the risk of futile recanalization for patients with BAO, as well as assist in the selection of appropriate candidates for EVT.

Background In the recent decades, the development of novel digital health technologies enables doctors to monitor ECG and vital signs remotely. But the data on applying the noninvasive wearable smartwatch on patients with transcatheter aortic valve replacement (TAVR) are unknown. Methods and Results We performed a prospective, observational cohort study to evaluate the feasibility of a novel, virtual, and remote health care strategy for patients with TAVR discharged to home with smart wearable devices. A total of 100 consecutive patients with severe aortic stenosis who underwent elective transfemoral TAVR were enrolled and received the Huawei smartwatch at least 1 day before TAVR. Vital signs, including heart rate, rhythm, oxygen saturation, and activity, were continuously recorded. Single‐lead ECG was recorded twice per day in the week following TAVR discharge and at least 2 days a week for the subsequent month after TAVR discharge. A designated heart team member provided remote health care with the data from the smartwatch when the patient had a need. Thirty‐eight cardiac events were reported in 34 patients after discharge, with most of the events (76.0%) detected and confirmed by the smartwatch. Six patients were advised and readmitted to the hospital for arrhythmia events detected by the smartwatch, of whom 4 patients received pacemaker implantation. The remaining 28 (82.4%) patients received telemedicine monitoring instead of face‐to‐face clinical visits, and 3 of them received new medication treatment under the online guidance of doctors. New‐onset left branch bundle block was found in 48 patients, with transient characteristics, and recovered spontaneously in 30 patients, and new‐onset atrial fibrillation was detected in 4 patients. There were no significant differences in the average weekly heart rates or the ratio of abnormal or low oxygen saturation when compared with the baseline. The average daily steps increased over time significantly (baseline, 870±1353 steps; first week, 1986±2406 steps; second week, 2707±2716 steps; third week, 3059±3036 steps; fourth week, 3678±3485 steps, P

Background and Purpose: Treatment for mild stroke remains an open question. We aim to develop a decision support tool based on machine learning (ML) algorithms, called DAMS (Disability After Mild Stroke), to identify mild stroke patients who would be at high risk of post-stroke disability (PSD) if they only received medical therapy and, more importantly, to aid neurologists in making individual clinical decisions in emergency contexts.Methods: Ischemic stroke patients were prospectively recorded in the National Advanced Stroke Center of Nanjing First Hospital (China) between July 2016 and September 2020. The exclusion criteria were patients who received thrombolytic therapy, age 5. The primary outcome was PSD, corresponding to 3-month mRS ≥ 2. We developed five ML models and assessed the area under curve (AUC) of receiver operating characteristic, calibration curve, and decision curve analysis. The optimal ML model was selected to be DAMS. In addition, SHapley Additive exPlanations (SHAP) approach was introduced to rank the feature importance. Finally, rapid-DAMS (R-DAMS) was constructed for a more urgent situation based on DAMS.Results: A total of 1,905 mild stroke patients were enrolled in this study, and patients with PSD accounted for 23.4% (447). There was no difference in AUCs between the five models (ranged from 0.691 to 0.823). Although there was similar discriminative performance between ML models, the support vector machine model exhibited higher net benefit and better calibration (Brier score, 0.159, calibration slope, 0.935, calibration intercept, 0.035). Therefore, this model was selected for DAMS. In addition, SHAP approach showed that the most crucial feature was NIHSS on admission. Finally, R-DAMS was constructed and there was similar discriminative performance between R-DAMS and DAMS, but the former performed worse on calibration.Conclusions: DAMS and R-DAMS, as prediction-driven decision support tools, were designed to aid clinical decision-making for mild stroke patients in emergency contexts. In addition, even within a narrow range of baseline scores, NIHSS on admission is the strongest feature that contributed to the prediction.

Background: Patient-specific computer simulation of transcatheter aortic valve replacement (TAVR) can provide unique insights in device-patient interaction.Aims: This study was to compare transcatheter aortic valve sealing behavior in patients with bicuspid aortic valves (BAV) and tricuspid aortic valves (TAV) through patient-specific computational modeling.Methods: Patient-specific computer simulation was retrospectively performed with FEops HEARTguide for TAVR patients. Simulation output was compared with postprocedural computed tomography and echocardiography to validate the accuracy. Skirt malapposition was defined by a distance larger than 1 mm based on the predicted device-patient interaction by quantifying the distance between the transcatheter heart valve (THV) skirt and the surrounding anatomical regions.Results: In total, 43 patients were included in the study. Predicted and observed THV frame deformation showed good correlation (R2 ≥ 0.90) for all analyzed measurements (maximum diameter, minimum diameter, area, and perimeter). The amount of predicted THV skirt malapposition was strongly linked with the echocardiographic grading of paravalvular leakage (PVL). More THV skirt malapposition was observed for BAV cases when compared to TAV cases (22.7 vs. 15.5%, p < 0.05). A detailed analysis of skirt malapposition showed a higher degree of malapposition in the interleaflet triangles section for BAV cases as compared to TAV patients (11.1 vs. 5.8%, p < 0.05).Conclusions: Patient-specific computer simulation of TAVR can accurately predict the behavior of the Venus A-valve. BAV patients are associated with more malapposition of the THV skirt as compared to TAV patients, and this is mainly driven by more malapposition in the interleaflet triangle region.

Biogenic amines (BAs) are produced by microbial decarboxylation in various foods. Histamine and tyramine are recognized as the most toxic of all BAs. Applying degrading amine enzymes such as multicopper oxidase (MCO) is considered an effective method to reduce BAs in food systems. This study analyzed the characterization of heterologously expressed MCO from L. sakei LS. Towards the typical substrate 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), the optimal temperature and pH for recombinant MCO (rMCO) were 25 °C and 3.0, respectively, with the specific enzyme activity of 1.27 U/mg. Then, the effect of different environmental factors on the degrading activity of MCO towards two kinds of BAs was investigated. The degradation activity of rMCO is independent of exogenous copper and mediators. Additionally, the oxidation ability of rMCO was improved for histamine and tyramine with an increased NaCl concentration. Several food matrices could influence the amine-oxidizing activity of rMCO. Although the histamine-degrading activities of rMCO were affected, this enzyme reached a degradation rate of 28.1% in the presence of surimi. Grape juice improved the tyramine degradation activity of rMCO by up to 31.18%. These characteristics of rMCO indicate that this enzyme would be a good candidate for degrading toxic biogenic amines in food systems.

In this study, three Lactiplantibacillus plantarum, namely 3-14-LJ, M22, and MB1, with high acetate esterase activity, acid, salt, and high-temperature tolerance were selected from 708 strains isolated from fermented food. Then, L. plantarum strains MB1, M22, and 3-14-LJ were inoculated at 107 CFU/mL in the model and 107 CFU/g in actual Suanzhayu systems, and the effects during fermentation on the physicochemical properties, amino acid, and volatile substance were investigated. The results showed that the inoculated group had a faster pH decrease, lower protein content, higher TCA-soluble peptides, and total amino acid contents than the control group in both systems (p < 0.05). Inoculation was also found to increase the production of volatile compounds, particularly esters, improve the sour taste, and decrease the bitterness of the product (p < 0.05). L. plantarum M22 was more effective than the other two strains in stimulating the production of isoamyl acetate, ethyl hexanoate, and ethyl octanoate. However, differences were discovered between the strains as well as between the model and the actual systems. Overall, the isolated strains, particularly L. plantarum M22, have good fermentation characteristics and have the potential to become excellent Suanzhayu fermenters in the future.

Ethyl carbamate (EC), classified as a Group 2A carcinogen, is most abundant in the fermented foods, such as Cachaca, Shaoxing wine, and Chinese liquor (baijiu). Although biodegradation can reduce its concentration, a high ethanol concentration and acidic environment often limit its degradation. In the present study, a novel ethyl carbamate hydrolase (ECH) with high specificity to EC was isolated from Acinetobacter calcoaceticus, and its enzymatic properties and EC degradability were investigated. ECH was immobilized to resist extreme environmental conditions, and the flavor substance changes were explored by gas chromatography-mass spectrometry (GC/MS). The specific enzymatic activity of ECH was 68.31 U/mg. Notably, ECH exhibited excellent thermal stability and tolerance to sodium chloride and high ethanol concentration (remaining at 40% activity in 60% (v/v) ethanol, 1 h). The treatment of immobilized ECH for 12 h decreased the EC concentration in liquor by 71.6 μg/L. Furthermore, the immobilized ECH exerted less effect on its activity and on the flavor substances, which could be easily filtrated during industrial production.

Abstract Background Lipid accumulation by oleaginous microorganisms is of great scientific interest and biotechnological potential. While nitrogen limitation has been routinely employed, low-cost raw materials usually contain rich nitrogenous components, thus preventing from efficient lipid production. Inorganic phosphate (Pi) limitation has been found sufficient to promote conversion of sugars into lipids, yet the molecular basis of cellular response to Pi limitation and concurrent lipid accumulation remains elusive. Results Here, we performed multi-omic analyses of the oleaginous yeast Rhodosporidium toruloides to shield lights on Pi-limitation-induced lipid accumulation. Samples were prepared under Pi-limited as well as Pi-repleted chemostat conditions, and subjected to analysis at the transcriptomic, proteomic, and metabolomic levels. In total, 7970 genes, 4212 proteins, and 123 metabolites were identified. Results showed that Pi limitation facilitates up-regulation of Pi-associated metabolism, RNA degradation, and triacylglycerol biosynthesis while down-regulation of ribosome biosynthesis and tricarboxylic acid cycle. Pi limitation leads to dephosphorylation of adenosine monophosphate and the allosteric activator of isocitrate dehydrogenase key to lipid biosynthesis. It was found that NADPH, the key cofactor for fatty acid biosynthesis, is limited due to reduced flux through the pentose phosphate pathway and transhydrogenation cycle and that this can be overcome by over-expression of an endogenous malic enzyme. These phenomena are found distinctive from those under nitrogen limitation. Conclusions Our data suggest that Pi limitation activates Pi-related metabolism, RNA degradation, and TAG biosynthesis while inhibits ribosome biosynthesis and TCA cycle, leading to enhanced carbon fluxes into lipids. The information greatly enriches our understanding on microbial oleaginicity and Pi-related metabolism. Importantly, systems data may facilitate designing advanced cell factories for production of lipids and related oleochemicals.

This work investigated the effect of lipase addition on a Chinese traditional fermented fish product, Suanzhayu. The accumulation of lactic acid and the decrease of pH during the fermentation were mainly caused by the metabolism of Lactobacillus. The addition of lipase had little effect on pH and the bacterial community structure but promoted the growth of Proteus. The addition of lipase promotes the formation of volatile compounds, especially aldehydes and esters. The formation of volatile compounds is mainly divided into three stages, and lipase had accelerated the fermentation process. Lactobacillus, Enterococcus and Proteus played an important role not only in inhibition of the growth of Escherichia-Shigella, but also in the formation of flavor. This study provides a rapid fermentation method for the Suanzhayu process.

Chouguiyu, a Chinese traditional fermented fish, is famous for its uniquely strong odor and desirable taste. However, traditional spontaneous fermentation often resulted in contamination and unstable quality of products. In this study, individual or conjunctive inoculation of two indigenous lactic acid bacteria (LAB), Lactococcus lactis M10 and Weissella cibaria M3, was tested for their effect on improving Chouguiyu’s quality. It was shown that inoculation would not affect the system’s pH, while increased the total bacteria count and lactic acid bacteria amounts. Matrix-assisted laser desorption/ionization time-of-flight mass (MALDI-TOF) analysis results revealed that Lactoc. lactis M10 and W. cibaria M3 could quickly occupy a dominant position in the ecosystem, and Lactoc. lactis M10 played an important role in the control of spoilage bacteria. Volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), and biogenic amines results also showed that Lactoc. lactis M10 had a positive effect on improving the product’s quality. Co-inoculation of Lactoc. lactis M10 and W. cibaria M3 could promote the formation of flavor according to the E-nose and gas chromatography-mass spectrometer (GC-MS) analyses, especially for the aroma-active and key volatile compounds. PCA plots of E-nose and hierarchical clustering analysis of GC-MS profiles revealed that the co-inoculation sample at the fifth day (LW5) was the most similar to the natural fermentation sample at the seventh day (C7). The overall acceptance of LW5 was also the closest to that of C7 in sensory evaluation. In conclusion, mixed starter culture was shown to have a good effect on improving product quality and enhancing flavor with fermentation time shortened by 29%.

The microbial community during the fermentation of industrial paocai, a lactic acid fermented vegetable food, was investigated via combined denaturing gradient gel electrophoresis (DGGE) and metagenomic sequencing. Firmicutes and Proteobacteria were identified as the dominant phyla during the fermentation. DGGE results of the bacterial community analysis showed that many genera were observed during the fermentation of industrial paocai, but the same predominant genus and species were observed: Lactobacillus and Lactobacillus (L.) alimentarius/L. paralimentarius. The abundance of L. alimentarius/L. paralimentarius increased fast during the initial stage of fermentation and approximately remained constant during the later stage. Metagenomic sequencing was used to finally identify the predominant species and their genetic functions. Metabolism was the primary functions of the microbial community in industrial paocai fermentation, including carbohydrate metabolism (CM), overview (OV), amino acid metabolism (AAM), nucleotide metabolism (NM), energy metabolism (EM), etc. The predominant species L. alimentarius and L. paralimentarius were involved in plenty of pathways in metabolism and played different roles in the metabolism of carbohydrate, amino acid, lipid to form flavor compounds during industrial paocai fermentation. This study provided valuable information about the predominant species in industrial paocai and its functional properties, which could enable us to advance our understanding of the fermentation mechanism during fermentation of industrial paocai. Our results will advance the understanding of the microbial roles in the industrial paocai fermentation and provide a theoretical basis for improving the quality of industrial paocai products.

A new sea urchin polysaccharide (SUP) was extracted from the gonad of sea urchin (Strongylocentrotus intermedius), and its bioactivity to synergistically enhance the functionality of bone morphogenetic protein-2 (BMP-2) induced osteoblastic differentiation was characterized. Results showed that the SUP is homogenous with an average molecular weight of 4.4 kDa, and it is mainly composed of mannose with a small number of glucose and N-acetylglucosamine, with a backbone of alternating 1, 4-D-Man and 1, 3-D-Man residues. The SUP was shown to synergistically enhance BMP-2 induced osteoblastic differentiation in C2C12 myoblast cells, evidenced by a significant increase in the activity of alkaline phosphatase (ALP), when the concentration of the SUP was higher than 10 µg/mL. The elevated ALP activity was also confirmed by histochemical staining of C2C12 myoblast cells. These results suggest that the SUP can promote bone regeneration and may serve as a functional food supplement for bone health.

Background and purpose: Futile recanalization occurs when the endovascular thrombectomy (EVT) is a technical success but fails to achieve a favorable outcome. This study aimed to use machine learning (ML) algorithms to develop a pre-EVT model and a post-EVT model to predict the risk of futile recanalization and to provide meaningful insights to assess the prognostic factors associated with futile recanalization. Methods: Consecutive acute ischemic stroke patients with large vessel occlusion (LVO) undergoing EVT at the National Advanced Stroke Center of Nanjing First Hospital (China) between April 2017 and May 2021 were analyzed. The baseline characteristics and peri-interventional characteristics were assessed using four ML algorithms. The predictive performance was evaluated by the area under curve (AUC) of receiver operating characteristic and calibration curve. In addition, the SHapley Additive exPlanations (SHAP) approach and partial dependence plot were introduced to understand the relative importance and the influence of a single feature. Results: A total of 312 patients were included in this study. Of the four ML models that include baseline characteristics, the "Early" XGBoost had a better performance {AUC, 0.790 [95% confidence intervals (CI), 0.677-0.903]; Brier, 0.191}. Subsequent inclusion of peri-interventional characteristics into the "Early" XGBoost showed that the "Late" XGBoost performed better [AUC, 0.910 (95% CI, 0.837-0.984); Brier, 0.123]. NIHSS after 24 h, age, groin to recanalization, and the number of passages were the critical prognostic factors associated with futile recanalization, and the SHAP approach shows that NIHSS after 24 h ranks first in relative importance. Conclusions: The "Early" XGBoost and the "Late" XGBoost allowed us to predict futile recanalization before and after EVT accurately. Our study suggests that including peri-interventional characteristics may lead to superior predictive performance compared to a model based on baseline characteristics only. In addition, NIHSS after 24 h was the most important prognostic factor for futile recanalization. [ABSTRACT FROM AUTHOR]

BACKGROUND: This study aims to evaluate limited data about daily physical activity patterns, influential factors, and their association with 1-year mortality or rehospitalization after transcatheter aortic valve replacement (TAVR) through smartwatches. METHODS: Consecutive severe aortic stenosis patients undergoing elective transfemoral TAVR in a Chinese tertiary hospital were enrolled from July 2021 to May 2022 and received a Huawei smartwatch at least 1 day before TAVR. The primary outcome was a composite of all-cause mortality or hospital readmission within 1 year. Linear mixed-effects models were applied to determine influential factors of daily step counts, and Cox proportional hazard regression models were to estimate the association between baseline step counts within 1 month since discharge and composite outcome from months 2 to 12. The dose-response association was assessed using restricted cubic spline curves. RESULTS: A total of 222 participants and 59 469 valid monitoring person-day records were included (mean age, 72.7 years; 61% women). Step counts increased rapidly within the first 2 months (P<0.001), followed by a slower increase for those without composite outcomes (P=0.029) and a gradual decrease for those who developed composite outcomes (P<0.001). In multivariate linear mixed models, a 1-m increase in baseline 6-minute walk test and a 1-month delay after discharge were associated with 4 (95% CI, 1--7) and 170 (95% CI, 145--194) additional step counts, respectively. In restricted cubic spline analysis, the hazard ratio declined progressively until ≈5000 steps per day, after which they leveled. Below 5000 steps, the adjusted hazard ratio of composite outcome associated with each 1000-step count increase was 0.67 (0.50--0.89; P=0.007). However, above 5000 steps, step counts were not significantly associated with the composite outcome (P=0.645), with a hazard ratio of 1.12 (0.70--1.79). CONCLUSIONS: Daily step counts rapidly increased within the first 2 months post-TAVR. Increased physical activity was associated with a lower risk of 1-year mortality or rehospitalization after TAVR for patients with daily step counts below 5000. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04454177. [ABSTRACT FROM AUTHOR]