Novel peptides from sea cucumber intestines hydrolyzed by neutral protease alleviate exercise-induced fatigue via upregulating the glutaminemediated Ca2+ /Calcineurin signaling pathway in mice.

Sea cucumber intestines are considered a valuable resource in the sea cucumber processing industry due to their balanced amino acid composition. Studies have reported that peptides rich in glutamate and branched-chain amino acids have anti-fatigue properties. However, the function of the sea cucumber intestine in reducing exercise-induced fatigue remains unclear. In this study, we enzymatically hydrolyzed low molecular weight peptides from sea cucumber intestines (SCIP) and administered SCIP orally to mice to examine its effects on exercise-induced fatigue using swimming and pole-climbing exhaustion experiments. The results revealed that supplementation with SCIP significantly prolonged the exhaustion time of swimming in mice, decreased blood lactate and urea nitrogen levels, and increased liver and muscle glycogen levels following a weight-loaded swimming test. Immunofluorescence analysis indicated a notable increase the proportion of slow-twitch muscle fiber and a significant decrease the proportion of fast-twitch muscle fiber following SCIP supplementation. Furthermore, SCIP upregulated mRNA expression levels of Ca2+ /Calcineurin upstream and downstream regulators, thereby contributing to the promotion of skeletal muscle fiber type conversion. This study presents the initial evidence establishing SCIP as a potential enhancer of skeletal muscle fatigue resistance, consequently providing a theoretical foundation for the valuable utilization of sea cucumber intestines.

Effects of intensive blood-pressure treatment on myocardial work in elderly hypertensive patients: A subcenter study of the STEP randomized controlled trial.

BACKGROUND: The benefits and safety of intensive blood pressure treatment in elderly hypertensive patients have been proved in the STEP trial. However, relevant mechanisms for intensive treatment are lacking. HYPOTHESIS: We aimed to explore whether intensive blood pressure treatment is associated with left ventricular systolic function changes as evaluated by myocardial work (MW) parameters in elderly hypertensive patients compared to the standard. METHODS: Patients were randomized to the intensive group (n = 66, median age 66 years, 42.4% male) with a systolic blood pressure (SBP) goal of 110 to <130 mmHg or the standard treatment group (n = 50, median age 63.5 years, 30% male) with an SBP goal of 130-<150 mmHg in this subcenter study of the STEP trial. There was no pre-randomization echocardiographic collected. Echocardiographic exam was produced at 1-year (phase 1) and 3-year (phase 2) post-randomization. RESULTS: In phase 1, SBP was already significantly lower in the intensive treatment group than in the standard treatment group (126.5 vs. 132.1 mmHg, p < .05). During a median follow-up of 40 months, in phase 2, the intensive group still had a lower SBP than the standard treatment group (125.0 vs. 135.3 mmHg, p < .05). Both global work index (GWI) and global constructive work (GCW) decreased significantly in phase in the intensive treatment group but not in the standard group (p < .05). Global wasted work (GWW) increased and global work efficiency (GWE) declined in both groups from phase 1 to phase 2 while no significant difference between the treatment effects. Similarly, left ventricular ejection function (LVEF) and global longitudinal strain (GLS) decreased in the two groups. The multivariate linear regression analysis showed the intensive treatment appeared to be an independent predictor of the ΔGWI (ß = -110.92; 95% CI, -197.78 to -30.07, p = .008) and ΔGCW (ß = -135.11; 95% CI, -220.33 to -49.88, p = .002). CONCLUSIONS: In elderly hypertensive patients, lower SBP was associated with decreased GWI and GCW and intensive BP treatment did not improve global MW efficiency.

Icariside II prevents kidney fibrosis development in chronic kidney disease by promoting fatty acid oxidation.

Renal interstitial fibrosis (RIF) is the main pathological basis for the progression of chronic kidney disease (CKD), however, effective interventions are limited. Here, we investigated the effect of Icariside II (ICA-II) on RIF and explored the underlying mechanisms. Rats receiving 5/6 ablation and infarction (A/I) surgery were gavaged with ICA-II (5 or 10 mg/kg) for 8 weeks. In vitro, TGF-ß1-stimulated NRK-52E cells were treated with ICA-II and (or) oleic acid, etomoxir, ranolazine, fenofibrate, and GW6471. The effects of ICA-II on RIF, fatty acid oxidation, lipid deposition, and mitochondrial function were determined by immunoblotting, Oil red O staining, colorimetric, and fluorometric assays. Using adeno-associated virus injection and co-culture methods, we further determined mechanisms of ICA-II anti-RIF. ICA-II ameliorated the fibrotic responses in vivo and in vitro. RNA-seq analysis indicated that ICA-II regulated fatty acid degradation and PPAR pathway in 5/6 (A/I) kidneys. ICA-II attenuated lipid accumulation and up-regulated expression of PPARα, CPT-1α, Acaa2, and Acadsb proteins in vivo and in vitro. Compared to ICA-II treatment, ICA-II combined with Etomoxir exacerbated mitochondrial dysfunction and fibrotic responses in TGF-ß-treated NRK-52E cells. Importantly, we determined that ICA-II improved lipid metabolism, fatty acid oxidation, mitochondrial function, and RIF by restoring PPARα. Co-culture revealed that ICA-II decreased the expression of Fibronectin, Collagen-I, α-SMA, and PCNA proteins in NRK-49F cells by restoring PPARα of renal tubular cells. ICA-II may serve as a promising therapeutic agent for RIF in 5/6 (A/I) rats, which may be important for the prevention and treatment of CKD.

Early Famine Exposure Results in Left Ventricular Remodeled, Diastolic Dysfunction and Systolic Function Preserved in Adults.

INTRODUCTION: Malnutrition during a critical window of development in a fetus or infant can result in abnormal cardiac remodeling and function. It is uncertain whether the contribution of these effects continues to impact the cardiac remodeling and function of adults over the course of several decades of growth. Our study examined the impact of early Chinese famine exposure on cardiac remodeling, left ventricular (LV) diastolic function, and LV systolic function in adults. METHODS: Participants at high risk of cardiovascular disease from the China Patient-Centered Evaluative Assessment of Cardiac Events Million Persons Project (PEACE MPP) were enrolled. The famine in China lasted from 1959 to 1962. A total of three groups were formed based on the participants' birth dates: pre-famine group, famine exposure group, and post-famine group. Logistic regression and linear mixed models were used to explore the association between famine exposure and cardiac remodeling, LV diastolic function and LV systolic function in adults. RESULTS: The study included 2,758 participants, the mean age was 57.05 years, 62.8% were female, 26.4% had LV hypertrophy (LVH), 59.6% had LV diastolic dysfunction (LVDD), and 10.5% had reduced global longitudinal strain (GLS). Compared to post-famine exposure, participants had independently increased risk of LVH in the famine exposure group (OR: 2.02, 95% CI: 1.60-2.56) and pre-famine exposure (OR: 1.36, 95% CI: 1.06-1.76). Compared to post-famine exposure, the risk of LVDD remarkably increased in the famine exposure group (OR: 3.04, 95% CI: 2.49-3.71) and pre-famine exposure group (OR: 1.87, 95% CI: 1.52-2.31). Famine exposure had no significant impact on GLS but was associated with a significant increase in LV ejection fraction (LVEF) and LV end-diastolic diameter (LVEDD). Significant interactions were observed between the effects of famine exposure and other clinical/sociodemographic variables (gender, systolic blood pressure [SBP] ≥140 mm Hg or not, high school or above or not, and annual income <50,000 RMB or not) on these outcomes. CONCLUSION: Exposure to famine, particularly during fetal and infant stages, increases the risk of LVH and LVDD in adults. However, the LV systolic function remains preserved. These impacts are more pronounced in females, individuals with SBP ≥140 mm Hg, those with low income, or those with high educational status.

Association of adiposity indices with cardiometabolic multimorbidity among 101,973 chinese adults: a cross-sectional study.

BACKGROUND: Cardiometabolic multimorbidity (CMM) and obesity represent two major health problems. The relationship between adiposity indices and CMM, however, remains understudied. This study aimed to investigate the associations of body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), a body shape index (ABSI), body roundness index (BRI), and conicity index (CI) with CMM among Chinese adults. METHODS: Data of 101,973 participants were collected from a population-based screening project in Southern China. CMM was defined as having two or more of the following diseases: coronary heart disease, stroke, hypertension, and diabetes. The relationship between the six adiposity indices and CMM was investigated by multivariate logistic regression and restricted cubic splines. Receiver operator characteristic curve, C-statistic and net reclassification index were used to estimate the discriminative and incremental values of adiposity indices on CMM. RESULTS: Logistic regression models showed the six adiposity indices were all significantly associated with the odds of CMM with non-linear relationships. For per SD increment, WC (Odds ratio [OR]: 1.66; 95% confidence interval (CI): 1.62-1.70) and WHtR (OR, 1.61; 95% CI, 1.58-1.65) were more significantly associated with a higher prevalence of CMM than BMI (OR, 1.55; 95% CI, 1.52-1.58) (all P < 0.05). In addition, WC, WHtR, and BRI displayed significantly better performance in detecting CMM compared with BMI (all P < 0.05). Their respective area under the curve (AUC) values were 0.675 (95% CI: 0.670-0.680), 0.679 (95% CI: 0.675-0.684), and 0.679 (95% CI: 0.675-0.684), while BMI yielded an AUC of 0.637 (95% CI: 0.632-0.643). These findings hold true across all subgroups based on sex and age. When Adding WC, WHtR, or BRI to a base model, they all provided larger incremental values for the discrimination of CMM compared with BMI (all P < 0.05). CONCLUSIONS: Adiposity indices were closely associated with the odds of CMM, with WC and WHtR demonstrating stronger associations than BMI. WC, WHtR, and BRI were superior to BMI in discriminative ability for CMM. Avoidance of obesity (especially abdominal obesity) may be the preferred primary prevention strategy for CMM while controlling for other major CMM risk factors.

Density functional theory studies of Ti3C2TxMXene nanosheets decorated with Au for sensing SF6/N2nitrogen-containing decomposition gases.

SF6/N2mixture is an alternative gas of SF6, which is already used in electrical equipment. When a malfunction occurs , SF6/N2will decompose and further react with trace water and oxygen to produce nitrogen-containing gases such as NO, NO2, N2O and NF3. It is necessary to monitor these gases to ensure the safe operation of the equipment. This paper is based on density functional theory (DFT), the nanomaterial Ti3C2Txdoped with Au atom was selected as sensing material. The result shows that Au/Ti3C2Txhas larger adsorption energy when NO and NO2adsorbed on the surface, the stable structures were conformed more easily with NO and NO2compared with N2O and NF3. The density of states analysis and the frontier molecule orbital analysis reveal more change of the system before and after NO and NO2adsorption, suggesting the material showed good sensitivity performance to NO and NO2. Thus, Au/Ti3C2Txis considered to have the potential for sensing NO and NO2.

Drought Eliminates the Difference in Root Trait Plasticity and Mycorrhizal Responsiveness of Two Semiarid Grassland Species with Contrasting Root System.

Root traits and arbuscular mycorrhizal (AM) fungi are important in determining the access of plants to soil resources. However, whether plants with different root systems (i.e., taproot vs. fibrous-root) exhibit different root trait plasticity and mycorrhizal responsiveness under drought remains largely unexplored. Tap-rooted Lespedeza davurica and fibrous-rooted Stipa bungeana were grown in monocultures in sterilized and live soils, followed by a drought treatment. Biomass, root traits, root colonization by AM fungi, and nutrient availability were evaluated. Drought decreased biomass and root diameter but increased the root:shoot ratio (RSR), specific root length (SRL), soil NO3--N, and available P for the two species. Under control and drought conditions, soil sterilization significantly increased the RSR, SRL, and soil NO3--N for L. davurica, but this only occurs under drought condition for S. bungeana. Soil sterilization significantly reduced AM fungal root colonization of both species, but drought significantly increased it in live soil. In water-abundant conditions, tap-rooted L. davurica may depend more on AM fungi than fibrous-rooted S. bungeana; however, under drought conditions, AM fungi are of equal importance in favoring both plant species to forage soil resources. These findings provide new insights for understanding the resource utilization strategies under climate change.

Recent advances in the detection of pathogenic microorganisms and toxins based on field-effect transistor biosensors.

In food safety analysis, the detection and control of foodborne pathogens and their toxins are of great importance. Monitoring of virus transmission is equally important, especially in light of recent findings that coronaviruses have been detected in frozen foods and packages during the current global epidemic of coronavirus disease 2019. In recent years, field-effect transistor (FET) biosensors have attracted considerable scholarly attention for pathogenic microorganisms and toxins detection and sensing due to their rapid response time, high sensitivity, wide dynamic range, high specificity, label-free detection, portability, and cost-effectiveness. FET-based biosensors can be modified with specific recognition elements, thus providing real-time qualitative and semiquantitative analysis. Furthermore, with advances in nanotechnology and device design, various high-performance nanomaterials are gradually applied in the detection of FET-based biosensors. In this article, we review specific detection in different biological recognition elements are immobilized on FET biosensors for the detection of pathogenic microorganisms and toxins, and we also discuss nonspecific detection by FET biosensors. In addition, there are still unresolved challenges in the development and application of FET biosensors for achieving efficient, multiplexed, in situ detection of pathogenic microorganisms and toxins. Therefore, directions for future FET biosensor research and applications are discussed.

Longitudinal Study of Left Ventricular Mass Index Trajectories and Risk of Mortality in Hypertension: A Cohort Study.

Background Left ventricular mass index (LVMI) has been extensively studied for its relationship with mortality but has been typically assessed at a single time point. We, therefore, describe the trajectory of LVMI in a population with hypertension over 6 years to study the subsequent risk of mortality. Methods and Results We assessed LVMI that was collected during annual health examinations in round 1 (2010-2012), round 2 (2013-2014), and round 3 (2015-2016) with 2 allometric scalings, height2.7, and body surface area, in a cohort of participants with hypertension to identify 6-year trajectories of LVMI by latent class trajectory modeling. We followed up with participants for mortality by latent trajectory from the last echocardiographic examination (September 17, 2014-December 8, 2016) to December 31, 2018. We calculated mortality hazard ratios by assigned trajectory using Cox proportional hazards models. We obtained data for LVMI from 2453 participants (mean age, 61.80 [SD, 12.14] years, 1428 [58.2%] female). We identified 3 trajectories of LVM/H2.7, characterized by maintained low stable (1298 [52.9%]); moderate stable (935 [38.1%]); high stable (220 [9.0%]), as well as 3 trajectories by LVM/body surface area. During a median follow-up of 2.15 years, 167 participants developed all-cause mortality, and 71 were cardiovascular mortality. Only the high stable trajectory was associated with a higher risk of all-cause mortality compared with the low stable trajectory by LVM/H2.7 or LVM/body surface area (all P<0.05). In Kaplan-Meier survival analysis, the trajectory with high stable LVM/body surface area had significantly lower survival probability. Conclusions In community hypertension, the individuals with high stable LVMI trajectory had the highest risk of all-cause mortality. The individuals in the moderate stable trajectory had a similar risk for mortality as those in the low stable trajectory.

Azithromycin Exposure Induces Transient Microbial Composition Shifts and Decreases the Airway Microbiota Resilience from Outdoor PM2.5 Stress in Healthy Adults: a Randomized, Double-Blind, Placebo-Controlled Trial.

Inappropriate antibiotic prescriptions are common for patients with upper respiratory tract infections (URTIs). Few data exist regarding the effects of antibiotic administration on airway microbiota among healthy adults. We conducted a randomized, double-blind, placebo-controlled trial to characterize the airway microbiota longitudinally in healthy adults using 16S rRNA gene sequencing and quantification. Both the induced sputum and oral wash samples were collected over a 60-day period following a 3-day intervention with 500 mg azithromycin or placebo. Environmental information, including air quality data (particulate matter [PM2.5] and PM10, air quality index [AQI] values), were also collected during the study. A total of 48 healthy volunteers were enrolled and randomly assigned into two groups. Azithromycin did not alter bacterial load but significantly reduced species richness and Shannon index. Azithromycin exposure resulted in a decrease in the detection rate and relative abundance of different genera belonging to Veillonellaceae, Leptotrichia, Fusobacterium, Neisseria, and Haemophilus. In contrast, the relative abundance of taxa belonging to Streptococcus increased immediately after azithromycin intervention. The shifts in the diversity of the microbiology composition took between 14 and 60 days to recover, depending on the measure used: either UniFrac phylogenetic distance or α-diversity. Outdoor environmental perturbations, especially the high concentration of PM2.5, contributed to novel variability in microbial community composition of the azithromycin group at D30 (30 days after baseline). The network analysis found that azithromycin altered the microbial interactions within airway microbiota. The influence was still obvious at D14 when the relative abundance of most taxa had returned to the baseline level. Compared to the sputum microbiota, oral cavity microbiota had a different pattern of change over time. The induced sputum microbial data can represent the airway microbiota composition in healthy adults. Azithromycin may have transient effects in the airway microbiota of healthy adults and decrease the airway microbiota resilience against outdoor environmental stress. The influence of azithromycin on microbial interactions is noteworthy, although the airway microbiota has returned to a near-baseline level. IMPORTANCE The influence of antibiotic administration on the airway microbiota of healthy adults remains unknown. This study is a randomized, double-blind, placebo-controlled trial aiming to investigate the microbial shifts in airways after exposure to azithromycin among heathy adults. We find that azithromycin changes the airway microbial community composition of healthy adults and decreases the airway microbiota resilience against outdoor environmental stress. This study depicts the longitudinal recovery trajectory of airway microbiota after the antibiotic perturbation and may provide reference for appropriate antibiotic prescription.

Shen Shuai II Recipe inhibits hypoxia-induced glycolysis by preserving mitochondrial dynamics to attenuate kidney fibrosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Shen Shuai II Recipe (SSR) is a traditional Chinese medicine prescription with significant clinical efficacy in chronic kidney disease (CKD) by invigorating Qi and resolving blood stasis, clearing away heat and dampness. Our previous studies demonstrated that SSR attenuated renal interstitial fibrosis (RIF) by improving hypoxia and mitochondrial dysfunction. AIM OF THE STUDY: The aim of this study was to investigate the potential mechanisms of SSR against RIF. MATERIALS AND METHODS: The CKD was established by 5/6 ablation/infarction (A/I) operation. After 4 weeks, rats were gavaged with SSR or Fenofibrate for 8 weeks. Hypoxia-treated NRK-52 E cells were treated with SSR and (or) glycolysis inhibitors, including GSK2837808 A (GSK) and 2-Deoxy-D-glucose (2-DG). In addition, Drp1-deficient or MFP-M1-treated NRK-52 E cells were treated with SSR under hypoxic conditions. The effects of SSR on fibrotic phenotype, glycolysis, mitochondrial dynamics and membrane potential in hypoxia-exposed NRK-52 E cells were examined by immunoblotting, colorimetric, and fluorometric methods. Furthermore, we constructed a lactic acid-induced activation model of NRK-49 F cells and a co-culture system. The activation of NRK-49 F cells was evaluated by immunoblotting method. RESULTS: Our findings indicated that SSR significantly attenuated abnormal glycolysis in vivo and in vitro, which was correlated with its renoprotective effect. Further studies revealed that improvement of mitochondrial dynamics could be one of the mechanisms by which SSR inhibits glycolysis to achieve anti-renal fibrosis. Furthermore, treatment with SSR significantly inhibited the lactic acid-induced activation of NRK-49 F cells. The co-culture results further highlighted that SSR inhibited activation of renal fibroblasts and deposition of extracellular matrix by reducing glycolysis in renal tubular cells. CONCLUSIONS: SSR alleviates RIF by inhibiting hypoxia-induced glycolysis through improvement of mitochondrial dynamics.

A micro-carbon nanotube transistor for ultra-sensitive, label-free, and rapid detection of Staphylococcal enterotoxin C in food.

Staphylococcal enterotoxin C (SEC) is an enterotoxin produced by Staphylococcus aureus, which can cause intestinal diseases. Therefore, it is of great significance to develop a sensitive detection method for SEC to ensure food safety and prevent foodborne diseases in humans. A field-effect transistor (FET) based on high-purity carbon nanotubes (CNTs) was used as a transducer, and a nucleic acid aptamer with high affinity was used for recognition to capture the target. The results indicated that the biosensor achieved an ultra-low theoretical detection limit of 1.25 fg/mL in PBS, and its good specificity was verified by detecting target analogs. Three typical food homogenates were used as the solution to be measured to verify that the biosensor had a swift response time (within 5 min after sample addition). An additional study with a more significant basa fish sample response also showed excellent sensitivity (theoretical detection limit of 8.15 fg/mL) and a stable detection ratio. In summary, this CNT-FET biosensor enabled the label-free, ultra-sensitive, and fast detection of SEC in complex samples. The FET biosensors could be further used as a universal biosensor platform for the ultrasensitive detection of multiple biological toxic pollutants, thus considerably stopping the spread of harmful substances.

Modeling Cardinality in Image Hashing.

Cardinality constraint, namely, constraining the number of nonzero outputs of models, has been widely used in structural learning. It can be used for modeling the dependencies between multidimensional labels. In hashing, the final outputs are also binary codes, which are similar to multidimensional labels. It has been validated that estimating how many 1's in a multidimensional label vector is easier than directly predicting which elements are 1 and estimating cardinality as a prior step will improve the classification performance. Hence, in this article, we incorporate cardinality constraint into the unsupervised image hashing problem. The proposed model is divided into two steps: 1) estimating the cardinalities of hashing codes and 2) then estimating which bits are 1. Unlike multidimensional labels that are known and fixed in the training phase, the hashing codes are generally learned through an iterative method and, therefore, their cardinalities are unknown and not fixed during the learning procedure. We use a neural network as a cardinality predictor and its parameters are jointly learned with the hashing code generator, which is an autoencoder in our model. The experiments demonstrate the efficiency of our proposed method.

Sex-specific risk factors of carotid atherosclerosis progression in a high-risk population of cardiovascular disease.

BACKGROUND: The progression of carotid intima-media thickness (cIMT) and plaques are associated with cardiovascular health, especially for high-risk population of cardiovascular disease (CVD). HYPOTHESIS: Risk factors for atherosclerosis may vary by sex. This study aimed to investigate the sex-specific risk factors of cIMT and plaque progression. METHODS: We selected subjects who were identified as high-risk population of CVD, and collected their carotid ultrasound data and baseline characteristics. Linear regression and logistic regression analyses were used to identify risk factors for cIMT and plaque progression. Sex-specific risk factors were identified respectively. RESULTS: A total of 7908 participants were included. The mean age was 57.75 ± 9.45 years and 61.51% were female. During mean follow-up of 1.92 ± 0.89 years, the median annual cIMT change rate was -7.25 µm/year. Seven hundred and fifteen subjects free from plaques at baseline developed plaque. Age, smoking, hypertension, and diabetes were common risk factors for carotid atherosclerosis progression in all participants. Smoking and alcohol drinking were significantly associated with increased cIMT change in women, while hypertension and antihypertensive medication were significant in men. Increased total cholesterol and diabetes were significantly associated with new plaque presence in women, while smoking, increased triglyceride, and dyslipidemia were significant in men (p ˂ .05 for all cases). The association of baseline cIMT and smoking with annual cIMT change rate and increased total cholesterol with new plaque presence were significantly differentiated between both sexes (p for interaction ˂ .05). CONCLUSIONS: The risk factors for cIMT and plaque progression differed by sex.

Soy isoflavone-specific biotransformation product S-equol in the colon: physiological functions, transformation mechanisms, and metabolic regulatory pathways.

Epidemiological data suggest that regular intake of soy isoflavones may reduce the incidence of estrogen-dependent and aging-associated disorders. Equol is a metabolite of soy isoflavone (SI) produced by specific gut microbiota and has many beneficial effects on human health due to its higher biological activity compared to SI. However, only 1/3 to 1/2 of humans are able to produce equol in the body, which means that not many people can fully benefit from SI. This review summarizes the recent advances in equol research, focusing on the chemical properties, physiological functions, conversion mechanisms in vitro and vivo, and metabolic regulatory pathways affecting S-equol production. Advanced experimental designs and possible techniques in future research plan are also fully discussed. Furthermore, this review provides a fundamental basis for researchers in the field to understand individual differences in S-equol production, the efficiency of metabolic conversion of S-equol, and fermentation production of S-equol in vitro.

The Detection of Foodborne Pathogenic Bacteria in Seafood Using a Multiplex Polymerase Chain Reaction System.

Multiplex polymerase chain reaction (PCR) assays are mainly used to simultaneously detect or identify multiple pathogenic microorganisms. To achieve high specificity for detecting foodborne pathogenic bacteria, specific primers need to be designed for the target strains. In this study, we designed and achieved a multiplex PCR system for detecting eight foodborne pathogenic bacteria using specific genes: toxS for Vibrio parahaemolyticus, virR for Listeria monocytogenes, recN for Cronobacter sakazakii, ipaH for Shigella flexneri, CarA for Pseudomonas putida, rfbE for Escherichia coli, vvhA for Vibrio vulnificus, and gyrB for Vibrio alginolyticus. The sensitivity of the single system in this study was found to be 20, 1.5, 15, 15, 13, 14, 17, and 1.8 pg for V. parahaemolyticus, L. monocytogenes, E. coli O157:H7, C. sakazakii, S. flexneri, P. putida, V. vulnificus, and V. alginolyticus, respectively. The minimum detection limit of the multiplex system reaches pg/µL detection level; in addition, the multiplex system exhibited good specificity and stability. Finally, the assays maintained good specificity and sensitivity of 104 CFU/mL for most of the samples and we used 176 samples of eight aquatic foods, which were artificially contaminated to simulate the detection of real samples. In conclusion, the multiplex PCR method is stable, specific, sensitive, and time-efficient. Moreover, the method is well suited for contamination detection in these eight aquatic foods and can rapidly detect pathogenic microorganisms.

Novel Peptides Derived from Sea Cucumber Intestine Promotes Osteogenesis by Upregulating Integrin-Mediated Transdifferentiation of Growth Plate Chondrocytes to Osteoblasts.

The sea cucumber intestine is a major by-product of sea cucumber processing and contains high levels of protein. In this study, we isolated and identified 28 novel osteogenic peptides from sea cucumber intestinal hydrolysis by the activity-tracking method for the first time. In vitro experimental results showed that compared with high molecular weight, the peptides from sea cucumber intestine (SCIP) with molecular weight <3 kDa more significantly promoted the proliferation and mineralized nodules of MC3T3-E1 cell and exhibited potential integrin binding capacity. In vivo experimental results showed that the SCIP supplement significantly increased the longitudinal bone length and elevated the height of the growth plate (especially the hypertrophic zone, 37.2%, p < 0.01) in adolescent mice. Further, immunofluorescence labeling results indicated that the SCIP supplement increased chondrocyte transdifferentiate to osteoblast in the growth plate close to the diaphysis. Mechanistically, transcriptome analysis revealed that the SCIP supplement induced the dedifferentiation of chondrocyte to osteoprogenitor cell via integrin-mediated histone acetylation and then redifferentiated to osteoblast via integrin-mediated Wnt/ß-catenin signaling. These results reported for the first time that sea cucumber intestine had the potential to develop into a dietary supplement for promoting osteogenic, and provide new evidence for the mechanism of dietary promotes chondrocyte to osteoblast transdifferentiation.

Ti3C2Tx as a Sensor for SF6/N2 Nitrogen-Containing Fault Decomposition Characteristic Products: A Theoretical Study.

The SF6/N2 gas mixture is an alternative gas to SF6. SF6/N2 will decompose and generate nitrogenous characteristic gases, such as NO, NO2, N2O, and NF3, when exposed to long-term partial discharge. The adsorption models of Ti3C2Tx (T=O, F, OH) and NO, NO2, N2O, NF3 were constructed, and the most stable adsorption structure was selected in this paper. The electron density and density of states of the adsorption system were further analyzed to study the adsorption behavior, and the sensing performance was evaluated in the end. The results are as follows: four gases could be spontaneously adsorbed on Ti3C2Tx, and strong adsorption occurred when surface terminal groups were OH, forming hydrogen or chemical bonds with significant charge transfer. Results show that Ti3C2(OH)2 had a stronger sensing ability than Ti3C2F2 and Ti3C2O2. The conductivity of the Ti3C2Tx with different terminal groups was improved after the adsorption of NO and NO2, showing Ti3C2Tx had a good sensing ability for NO and NO2. It was difficult for the four gases to desorb from the Ti3C2(OH)2 surface, but the adsorption on the Ti3C2F2, Ti3C2O2 surface had a short recovery time at room temperature.

Novel peptides from sea cucumber intestinal hydrolysates promote longitudinal bone growth in adolescent mice through accelerating cell cycle progress by regulating glutamine metabolism.

Sea cucumber intestines are recognized as a major by-product in the sea cucumber processing industry and have been shown to exhibit bioactive properties. However, whether the sea cucumber intestine is beneficial for osteogenesis remains unknown. In this study, low molecular weight peptides rich in glutamate/glutamine were obtained from sea cucumber intestines (SCIP) by enzymatic hydrolysis, and orally administered to adolescent mice to investigate the effects on longitudinal bone growth. The results showed that the SCIP supplement significantly increased the femur length and new bone formation rate by 9.6% and 56.3%, and elevated the levels of serum osteogenic markers alkaline phosphatase (ALP), Collagen I and osteocalcin (OCN). Notably, H&E staining showed that SCIP significantly increased the height of the growth plate, in which the height of the proliferation zone was elevated by 95.6%. Glutamine is a major determinant of bone growth. SCIP supplement significantly increased glutamine levels in the growth plate by 44.2% and upregulated the expression of glutamine metabolism-related enzymes glutaminase 1 (Gls1) and glutamate dehydrogenase 1 (GLUD1) in the growth plate. Furthermore, SCIP supplement upregulated growth plate acetyl coenzyme A levels to promote histone acetylation and accelerated cell cycle progression by upregulating Sox9 expression, thereby contributing to rapid chondrocyte proliferation. To the best of our knowledge, this is the first report where SCIP could enhance longitudinal bone growth via promoting growth plate chondrocyte proliferation. The present study will provide new ideas and a theoretical basis for the high-value utilization of sea cucumber intestines.