Decoding of Salty/Saltiness-Enhancing Peptides Derived from Goose Hemoglobin and the Interaction Mechanism with TMC4 Receptor.

Amid the growing concern for health-oriented food choices, salt reduction has received widespread attention, particularly in the exploitation of salt alternatives. Peptides with a saltiness-enhancing effect may provide an alternative method for salt reduction. The objective of this study was to isolate and extract novel peptides with salt-reducing effects by fermenting goose blood using a Lactobacillus plantarum strain. Five potential target peptides were screened by a virtual database prediction and molecular docking. Sensory evaluation and E-tongue analysis showed that five peptides (NEALQRM, GDAVKNLD, HAYNLRVD, PEMHAAFDK, and AEEKQLITGL) were identified as target peptides. Particularly, the results of E-tongue showed that GDAVKNLD can increase the saltiness intensity (2.87 ± 0.02) in the complex system. The sensory evaluation results also indicated an increase in saltiness intensity (46.67 ± 4.67 mmol/L NaCl) after adding GDAVKNLD. The results of molecular dynamics simulation indicated that five peptides have good ability to bind tightly to TMC4 receptor, thereby stimulating it to exert an active effect. And these peptides interacted with the TMC4 receptor via hydrogen bonding, hydrophobic interactions, and electrostatic interactions. This research lays a theoretical foundation for discovering novel salty/saltiness-enhancing peptides and provides meaningful contributions to efforts in salt reduction.

Reform of teaching and practice of the integrated teaching method BOPPPS-PBL in the course "clinical haematological test technique".

BACKGROUND: In order to meet the demand for laboratory talents in the clinical laboratory industry and address the current curriculum characteristics and shortcomings of the teaching mode of "Clinical Hematology Laboratory Technology", we investigated the effectiveness of the bridge-in, objective, pre-assessment, participatory learning, post-assessment, and summary model combined with problem-based learning (BOPPPS-PBL) in undergraduate teaching of this course. METHOD: Seventy students majoring in Medical Laboratory Technology from the Army Medical University in the past 5 years have been selected and divided into two groups with the same teaching content and time. The control group (2015 and 2016 grades) used traditional teaching methods, while the experimental group (2017, 2018 and 2019 grades) used the BOPPPS-PBL model. After class, diverse evaluation methods were used to analyze the formative and summative exam scores of the two groups of students. RESULTS: After the reform, students performed significantly better in exams than before. In addition, the new teaching methods have had a positive impact, with students demonstrating high motivation for self-directed learning and problem-solving abilities. CONCLUSION: Compared to traditional teaching methods. The BOPPPS-PBL integrated case study education model is a relatively effective teaching method to improve students' problem-solving ability and comprehensive practical ability.

Smartphone-enabled colorimetric immunoassay for deoxynivalenol based on Mn2+-mediated aggregation of AuNPs.

Deoxynivalenol (DON) is a common mycotoxin in food that mainly pollutes grain crops and feeds, such as barley, wheat and corn. DON has caused widespread concern in the field of food and feed safety. In this study, a colorimetric immunoassay was proposed based on the aggregation of gold nanoparticles (AuNPs) due to the decomposition of Mn2+ from gold-coated manganese dioxide (AuNP@MnO2) nanosheets. In this study, 2-(dihydrogen phosphate)-l-ascorbic acid (AAP) was hydrolyzed by alkaline phosphatase (ALP) and converted to ascorbic acid (AA). Then, AuNP@MnO2 was reduced to Mn2+ and AuNPs aggregation occurred. Using the unique optical characteristics of AuNPs and AuNP@MnO2, visible color changes realized simple detection of DON with high sensitivity and portability. With increasing DON content, the color changed more obviously. To quantitatively detect DON, pictures can be taken and the blue value can be read by a smartphone. The detection limit (Ic10) of this method was 0.098 ng mL-1, which was 326 times higher than that of traditional competitive ELISA, and the detection range was 0.177-6.073 ng mL-1. This method exhibited high specificity with no cross-reaction in other structural analogs. The average recovery rate of DON in corn flour samples was 89.1 %-110.2 %, demonstrating the high accuracy and stability of this assay in actual sample detection. Therefore, the colorimetric immunoassay can be used for DON-related food safety monitoring.

Taste properties and mechanism of umami peptides from fermented goose bones based on molecular docking and molecular dynamics simulation using umami receptor T1R1/T1R3.

Umami peptides are valuable taste substances due to their exceptional taste and beneficial properties. In this study, purification of fermented goose bone broth was performed using continuous chromatography and sensory analysis, and after identification through nano-LC-MS/MS, four umami peptides were screened out by umami activity prediction and molecular docking, which are VGYDAE, GATGRDGAR, GETGEAGER, and GETGEAGERG derived from collagen. Sensory analysis indicated that they were also umami-enhancing, with thresholds ranging from 0.41 to 1.15 mmol/L, among which GER9 was the best. Combining the results of docking and molecular dynamics simulation, it was known that hydrogen bond and electrostatic interactions were vital in driving the umami formation. Moreover, Glu, Ser, and Asp of umami receptor T1R1/T1R3 were the key residues for the binding between four umami peptides and T1R1/T1R3. These findings provide novel insights into the high-value utilization of goose bones and offer profound theoretical guidance for understanding the umami mechanism.

Composite starch films as green adsorbents for removing benzo[a]pyrene from smoked sausages.

Benzo[a]pyrene (BaP), which is emitted during the processing of smoked sausages, accumulates in sausages and poses a serious threat to human health. This study focused on the removal of BaP from sausages and accompanying particulate matter (PM) during the smoking of sausages by films formed by combining corn starch (CS) with K-carrageenan (KC)/sodium alginate (SA). Initially, the effects of different additions of KC and SA on the rheological analysis, thermogravimetric analysis (TGA) and film-forming properties of the composite films were investigated. The BaP reduction capacities of CS-KC and CS-SA composite films in sausage were 41.1%-47.0% and 54.2%-56.5%, respectively, because the three-dimensional mesh structure of the composite films provided a large number of adsorption sites. Finally, kinetic studies demonstrated that BaP control in composite films is mainly achieved by intraparticle diffusion. Therefore, due to its excellent recyclability and biodegradability, composite starch film has a promising application in smoked meat products.

Recombinase Polymerase Amplification-Based Biosensors for Rapid Zoonoses Screening.

Recent, outbreaks of new emergency zoonotic diseases have prompted an urgent need to develop fast, accurate, and portable screening assays for pathogen infections. Recombinase polymerase amplification (RPA) is sensitive and specific and can be conducted at a constant low temperature with a short response time, making it especially suitable for on-site screening and making it a powerful tool for preventing or controlling the spread of zoonoses. This review summarizes the design principles of RPA-based biosensors as well as various signal output or readout technologies involved in fluorescence detection, lateral flow assays, enzymatic catalytic reactions, spectroscopic techniques, electrochemical techniques, chemiluminescence, nanopore sequencing technologies, microfluidic digital RPA, and clustered regularly interspaced short palindromic repeats/CRISPR-associated systems. The current status and prospects of the application of RPA-based biosensors in zoonoses screening are highlighted. RPA-based biosensors demonstrate the advantages of rapid response, easy-to-read result output, and easy implementation for on-site detection, enabling development toward greater portability, automation, and miniaturization. Although there are still problems such as high cost with unstable signal output, RPA-based biosensors are increasingly becoming one of the most important means of on-site pathogen screening in complex samples involving environmental, water, food, animal, and human samples for controlling the spread of zoonotic diseases.

Smartphone-controlled biosensor for viral respiratory infectious diseases: Screening and response.

Outbreaks of emerging viral respiratory infectious diseases (VRIDs) including coronavirus disease 2019 (COVID-19) seriously endanger people's health. However, the traditional nucleic acid detection required professionals and larger instruments and antigen-antibody detection suffered a long window period of target generation. To facilitate the VRIDs detection in time for common populations, a smartphone-controlled biosensor, which integrated sample preparation (electromembrane extraction), biomarker detection (red-green-blue model) and remote response technology (a built-in APP), was developed in this work. With the intelligent biosensor, VRIDs could be recognized in the early stage by using endogenous hydrogen sulfide as the biomarker. Importantly, it only took 15 min to accomplish the whole process of screening and response to VRIDs. Moreover, the experimental data showed that this smartphone-controlled biosensor was suitable for ordinary residents and could successfully differentiate non-communicable respiratory diseases from VRIDs. To the best of our knowledge, this is the first time that a smartphone-controlled biosensor for screening and response to VRIDs was reported. We believe that the present biosensor will help ordinary residents jointly deal with the challenges brought by COVID-19 or other VRIDs in the future.

A loop-mediated isothermal amplification-enabled analytical assay for the detection of SARS-CoV-2: A review.

The number of words: 4645, the number of figures: 4, the number of tables: 1The outbreak of COVID-19 in December 2019 caused a global pandemic of acute respiratory disease, and with the increasing virulence of mutant strains and the number of confirmed cases, this has resulted in a tremendous threat to global public health. Therefore, an accurate diagnosis of COVID-19 is urgently needed for rapid control of SARS-CoV-2 transmission. As a new molecular biology technology, loop-mediated isothermal amplification (LAMP) has the advantages of convenient operation, speed, low cost and high sensitivity and specificity. In the past two years, rampant COVID-19 and the continuous variation in the virus strains have demanded higher requirements for the rapid detection of pathogens. Compared with conventional RT-PCR and real-time RT-PCR methods, genotyping RT-LAMP method and LAMP plus peptide nucleic acid (PNA) probe detection methods have been developed to correctly identified SARS-CoV-2 variants, which is also why LAMP technology has attracted much attention. LAMP detection technology combined with lateral flow assay, microfluidic technology and other sensing technologies can effectively enhance signals by nucleic acid amplification and help to give the resulting output in a faster, more convenient and user-friendly way. At present, LAMP plays an important role in the detection of SARS-CoV-2.

Ultrasound-assisted electromembrane extraction with supported semi-liquid membrane.

Electromembrane extraction (EME), involving the migration of charged analytes across a supported liquid membrane (SLM) with an external power supply, is a promising sample preparation method in analytical chemistry. However, the presence of boundary double layers at the SLM/solution interfaces often restricts extraction efficiency. To avoid this, the current work proposed an ultrasound-assisted EME (UA-EME) method based on a novel type of supported semi-liquid membrane (SsLM). The characterizations showed that the SsLM was stable under ultrasound conditions. Ultrasound was found to reduce the boundary double layers and thus increase the mass transfer. Major operational parameters in UA-EME including ultrasound power density, temperature, applied voltage and extraction time were optimized with haloperidol, fluoxetine, and sertraline as model analytes. Under the optimal conditions, extraction recoveries of model analytes in water samples were in the range of 66.8%-91.6%. When this UA-EME method was coupled with LC-MS/MS for detection of the target analytes in human urine samples, the linear range of the analytical method was 10-1000 ng mL-1, with R2 > 0.997 for all analytes. The limits of detection (LOD) and limits of quantification (LOQ) were in the range of 1.7-2.1 ng mL-1 and 5.7-6.7 ng mL-1, respectively. The UA-EME expands the application field of ultrasound chemistry and will be very important in development of stable and fast sample preparation systems in the future.

Recent sample pretreatment methods for determination of selective serotonin reuptake inhibitors (SSRIs) in biological samples.

Selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine (FLU), sertraline (SER), paroxetine (PAR), fluvoxamine (FLV) and citalopram (CIT) have been the first treatment drugs for pregnant and breastfeeding women. Quantitative analysis of SSRIs in biological samples is extremely needed in public health and clinical practice. During the analysis, sample pretreatment is an important step that can obtain an accurate quantitative analysis of SSRIs in the complex samples. The present paper discussed the recent development of sample preparation methods for SSRI analysis. Traditional sample preparation techniques such as liquid liquid extraction (LLE) and solid phase extraction (SPE), which have been widely used in the separation of SSRIs in biological samples, were extensively presented. Moreover, the new sample preparation techniques including liquid phase microextraction (LPME), solid phase microextraction (SPME), electromembrane extraction (EME) and other miniaturized extraction techniques, which are becoming highly popular in SSRI analysis, were also critically reviewed. In this review, both the advantages and disadvantages of these sample pretreatment methods were addressed. As a summary, we prospected the challenges and promising directions for the future of sample pretreatment methods in SSRI analysis.

Highly recyclable cysteamine-modified acid-resistant MOFs for enhancing Hg (II) removal from water.

Thiol-functionalized metal-organic frameworks (MIL-101-SH and UiO-66-SH) were synthesized by a post-synthetic modification method as the proper adsorbents for Hg (II) removal from water. This facile method for the synthesis of UiO-66-SH was developed via a condensation reaction between cysteamine and carboxyl groups present in the framework of UiO-66-COOH. MIL-101 was functionalized by grafting amine group of cysteamine on coordinatively unsaturated chromium ions centres, yielding to MIL-101-SH adsorbents. These two types of thiol-functionalized MOFs samples by cysteamine-modified were characterized by XRD, XPS, FTIR and N2 adsorption-desorption isotherms respectively, which prove the successful modification of the thiol groups. The maximum adsorption capacities of mercury ions for UiO-66-SH and MIL-101-SH adsorbents were 110 and 250 mg/g at pH of 5, respectively. Moreover, the acidic medium could effectively elute Hg (II) and the adsorbents can be well reusable.

Genetic variants in microRNAs are associated with cervical cancer risk.

Because genetic variants in microRNAs (miRNAs) or their surrounding regions can alter miRNA processing, expression and final biological function, we investigated whether miRNA single-nucleotide polymorphisms (SNPs) are associated with cervical cancer (CC) susceptibility. Common miRNA SNPs (i.e. miR-146a rs2910164, miR-149 rs2292832, miR-196a2 rs11614913, miR-499 rs3746444, miR-605 rs2043556 and miR-618 rs2682818) were genotyped in the 954 patients and 1339 controls. The results showed that the miR-149 rs2292832 TC/CC genotypes were associated with a 21% increased risk of CC compared with the TT genotype [odds ratio (OR) = 1.21, 95% confidence interval (CI) = 1.00-1.47]. The association was more prominent among the subjects with age ≤ 48 years (OR = 1.55, 95% CI = 1.16-2.06), having history of abortion (OR = 1.44, 95% CI = 1.12-1.86), premenopausal status (OR = 1.41, 95% CI = 1.08-1.85) and patients with clinical stage II of CC (OR = 1.43, 95% CI = 1.08-1.90). The expression plasmids containing the pre-miR-149 sequence with C allele of rs2292832 transcribed higher amount of mature miR-149-5p/3p than these with T allele in the HeLa and SiHa cells. Therefore, the rs2292832 polymorphism might influence CC susceptibility through modulation of the procession of pre-miR-149 to mature miRNAs.

A novel monolith ZnS-ZIF-8 adsorption material for ultraeffective Hg (II) capture from wastewater.

A novel monolithic adsorption material (ZnS-ZIF-8) was well prepared by means of the functionalized filter paper and explored for Hg (II) capture in wastewater in this work. The novel monolith ZnS-ZIF-8 displayed outstanding capture efficiency toward Hg (II) in the solution containing competitive diverse metal ions within very short time. The adsorption behavior was well fitted with the Langmuir adsorption model and the maximum adsorption capacities for Hg (II) removal was up to 925.9 mg/g. The Hg (II) captured by ZnS-ZIF-8 can be reclaimed by elution with Na2S solution. The approach of this novel monolith adsorption material displayed the advantages of rapidity, simplicity, selectivity and could be expected to the development of a rapid and efficient device to purify Hg (II) from wastewater in form of the integration filter-adsorption column.

[Spectral Analysis on the Decolorization of Dyeing Wastewater with PAC-PDMDAAC Hybrid Flocculant].

The new hybrid flocculant polyaluminum chloride-poly (dimethyl diallyl ammonium chloride) (PAC-PDMDAAC) was used to treat disperse violet and reactive brilliant red dye wastewater. The experimental results indicated that the decolorization effect of hybrid PAC-PDMDAAC was better than that of PAC and composite PAC-PDMDAAC. The decolorization rates of disperse violet and reactive brilliant red dye wastewater were 99% and 86.8% respectively when the dosages of hybrid flocculant were 400 and 450 mg·L-1. When the pH of disperse violet wastewater was 7～12, the hybrid flocculant had the best decolorization effect. When the pH of reactive brilliant red wastewater was 7～9, the hybrid flocculant had the best decolorization effect. Each of the two dyes and their flocs were characterized with FTIR. Results showed that the hybrid flocculant had a complex reaction with the dye wastewater, and the main decolorization mechanism was charge neutralization and adsorption bridging capacity. The UV scanning results indicated an adsorption peaks shift and an absorbance decreases, which further explained the main mechanism above. At the same time, it also indicated the ether linkage and ­NH2 of disperse violet were destroyed and replaced by hybrid flocculant, and the -SO3 , Cl- of reactive brilliant red were also replaced. The study will provide a new method in decolorization effiency and decolorization mechanism for the new inorganic-organic hybrid polymer flocculant. And it has significant practical meaning and application value.