Hepatic kynurenic acid mediates phosphorylation of Nogo-A in the medial prefrontal cortex to regulate chronic stress-induced anxiety-like behaviors in mice.

Exercise training effectively relieves anxiety disorders via modulating specific brain networks. The role of post-translational modification of proteins in this process, however, has been underappreciated. Here we performed a mouse study in which chronic restraint stress-induced anxiety-like behaviors can be attenuated by 14-day persistent treadmill exercise, in association with dramatic changes of protein phosphorylation patterns in the medial prefrontal cortex (mPFC). In particular, exercise was proposed to modulate the phosphorylation of Nogo-A protein, which drives the ras homolog family member A (RhoA)/ Rho-associated coiled-coil-containing protein kinases 1(ROCK1) signaling cascade. Further mechanistic studies found that liver-derived kynurenic acid (KYNA) can affect the kynurenine metabolism within the mPFC, to modulate this RhoA/ROCK1 pathway for conferring stress resilience. In sum, we proposed that circulating KYNA might mediate stress-induced anxiety-like behaviors via protein phosphorylation modification within the mPFC, and these findings shed more insights for the liver-brain communications in responding to both stress and physical exercise.

Identification of a novel Providencia species showing multi-drug-resistant in three patients with hospital-acquired infection.

Providencia species are important opportunistic pathogens for humans and are associated with several infectious diseases. In this study, we found three clinical strains belonging to a novel Providencia species, namely Providencia huashanensis, including strains CRE-3FA-0001T, CRE-138-0026, and CRE-138-0111. These strains were recovered from three patients, and all of them were associated with nosocomial infections, including surgical site, urinary tract, and intracranial infections. The three strains showed high-level resistance to many types of antimicrobials, including amikacin, aztreonam, ceftazidime, cefepime, ciprofloxacin, colistin, polymyxin B, imipenem, meropenem, ceftazidime-avibactam, imipenem-relebactam. Investigation of the resistance mechanism revealed that acquired resistance genes such as blaKPC, blaNDM, blaPER, blaOXA, aac, ant, qnrD, etc., played an important role in the multidrug-resistant phenotype for the three strains. The phylogenetic trees were reconstructed based on the 16S rRNA gene sequences, multi-locus sequence analysis, and core SNPs. The genome sequence of the strains had a range of 83.5-85.8% average nucleotide identity (ANI) and 21-25.5% in silico DNA-DNA hybridization (isDDH) score with other Providencia type strains. The ANI&isDDH values and the phylogenetic tree indicated that the strains CRE-3FA-0001T, CRE-138-0026, and CRE-138-0111 strains should be considered as a novel species of the genus Providencia, for which the name P. huashanensis sp. nov. is proposed. The type strain is CRE-3FA-0001T =CCTCC AB 2023186T=KCTC 8373T.

Stress increases hepatic release of lipocalin 2 which contributes to anxiety-like behavior in mice.

Chronic stress induces anxiety disorders via both neural pathways and circulating factors. Although many studies have elucidated the neural circuits involved in stress-coping behaviors, the origin and regulatory mechanism of peripheral cytokines in behavioural regulation under stress conditions are not fully understood. Here, we identified a serum cytokine, lipocalin 2 (LCN2), that was upregulated in participants with anxiety disorders. Using a mouse model of chronic restraint stress (CRS), circulating LCN2 was found to be related to stress-induced anxiety-like behaviour via modulation of neural activity in the medial prefrontal cortex (mPFC). These results suggest that stress increases hepatic LCN2 via a neural pathway, leading to disrupted cortical functions and behaviour.

Multiplex nanozymatic biosensing of Salmonella on a finger-actuated microfluidic chip.

A colorimetric biosensor was elaboratively designed for fast, sensitive and multiplex bacterial detection on a single microfluidic chip using immune magnetic nanobeads for specific bacterial separation, immune gold@platinum palladium nanoparticles for specific bacterial labeling, a finger-actuated mixer for efficient immunoreaction and two coaxial rotatable magnetic fields for magnetic nanobead capture (outer one) and magnet-actuated valve control (inner one). First, preloaded bacteria, nanobeads and nanozymes were mixed through a finger actuator to form nanobead-bacteria-nanozyme conjugates, which were captured by the outer magnetic field. After the inner magnetic field was rotated to successively wash the conjugates and push the H2O2-TMB substrate for resuspending these conjugates, colorless TMB was catalyzed into blue TMBox products, followed by color analysis using ImageJ software for bacterial determination. This simple biosensor enabled multiplex Salmonella detection as low as 9 CFU per sample in 45 min.

A novel electrochemical aptasensor based on core-shell nanomaterial labeling for simultaneous detection of acetamiprid and malathion.

At present, due to the coexistence of multiple pesticides in vegetables and the enhanced toxicity, a simultaneous detection method for multiple pesticides is urgently needed. In this work, two types of core-shell nanomaterials, Ag-Au core-shell nanoparticles (Ag@Au NPs) and Cu2O-Au core-shell nanoparticles (Cu2O@Au NPs), were synthesized and labeled with acetamiprid aptamer and malathion aptamer to prepare two novel electroactive signal probes, respectively. The two probes were hybridized on the surface of the electrode by the principle of base complementary pairing between the aptamers and the thiolated DNA oligonucleotide sequences, and a dual-signal electrochemical aptasensor for the simultaneous detection of acetamiprid and malathion was established by modified glassy carbon electrode (GCE). The limits of detection (LOD) were calculated to be 43.7 pg mL-1 for acetamiprid and 63.4 pg mL-1 for malathion. The aptasensor determined acetamiprid and malathion in spinach and rape with the recovery rates of 88.9%-112.5% and 98.0%-114.1%, respectively.

Dual-ratiometric aptasensor for simultaneous detection of malathion and profenofos based on hairpin tetrahedral DNA nanostructures.

Due to the diversification and complexity of organophosphorus pesticide residues brings great challenges to the detection work. Therefore, we developed a dual-ratiometric electrochemical aptasensor that could detect malathion (MAL) and profenofos (PRO) simultaneously. In this study, metal ions, hairpin-tetrahedral DNA nanostructures (HP-TDN) and nanocomposites were used as signal tracers, sensing framework and signal amplification strategy respectively to develop the aptasensor. Thionine (Thi) labeled HP-TDN (HP-TDNThi) provided specific binding sites for assembling Pb2+ labeled MAL aptamer (Pb2+-APT1) and Cd2+ labeled PRO aptamer (Cd2+-APT2). When the target pesticides were present, Pb2+-APT1 and Cd2+-APT2 were dissociated from the hairpin complementary strand of HP-TDNThi, resulting in reduced oxidation currents of Pb2+ (IPb2+) and Cd2+ (ICd2+), respectively, while the oxidation currents of Thi (IThi) remained unchanged. Thus, IPb2+/IThi and ICd2+/IThi oxidation current ratios were used to quantify MAL and PRO, respectively. In addition, the gold nanoparticles (AuNPs) encapsulated in the zeolitic imidazolate framework (ZIF-8) nanocomposites (Au@ZIF-8) greatly increased the catch of HP-TDN, thereby amplifying the detection signal. The rigid three-dimensional structure of HP-TDN could reduce the steric hindrance effect on the electrode surface, which could greatly improve the recognition efficiency of the aptasensor for the pesticide. Under the optimal conditions, the detection limits of the HP-TDN aptasensor for MAL and PRO were 4.3 pg mL-1 and 13.3 pg mL-1, respectively. Our work proposed a new approach to fabricating a high-performance aptasensor for simultaneous detection of multiple organophosphorus pesticides, opening a new avenue for the development of simultaneous detection sensors in the field of food safety and environmental monitoring.

Research on the experience of National Master of Traditional Chinese Medicine Professor Lu ZhiZheng in treating chronic atrophic gastritis based on data mining technology.

BACKGROUND: The purpose of this research is to summarize the academic expertise of Professor Lu Zhizheng in the treatment of Chronic Atrophic Gastritis, and to explain his clinical reasoning and common prescriptions in the treatment of CAG. METHODS: Professor Lu's outpatient cases of CAG from January 2008 to December 2021 were selected, and the PageRank algorithm was applied on the FangNet platform to analyze the usage frequencies of herbs, their four natures and five flavors according to Traditional Chinese Medicine, core herbs, and herb clustering patterns, with the goal of summarizing the distinguishing features of Professor Lu's academic and clinical approach to CAG. A total of 170 patients from 252 consultations were included in this study. The prescriptions involved a total of 239 herbs, which occurred a cumulative 4339 times. The herb natures were mainly warm, neutral, and slightly cold, and the herb flavors were predominantly sweet, bitter, and pungent. The channel tropism of the selected herbs primarily targeted the spleen, stomach, and lung meridians. Herb rank analysis showed that 34 herbs, including Gancao, Taizishen, Banxia, Huanglian, Shengjiang, Baizhu, Yiyiren, Maiya, Cangzhu, and Kuxingren, were the driver herbs used by Professor Lu for the treatment of CAG. RESULTS: Herb-herb co-occurrence/exclusivity analysis revealed 10 sets of frequently used herb pairs; herb cluster analysis yielded 10 herb clusters. These results reflected the emphasis Professor Lu placed on protecting Qi and Yin while clearing damp-heat. Professor Lu Zhizheng utilized dialectics reinforced with flexible thinking in the treatment of CAG, and emphasized that identifying the pathogenesis and addressing the syndrome should be prioritized. CONCLUSIONS: The characteristic treatment strategy aimed to replenish Qi and nourish Yin, clear away damp-heat, and treat CAG patients comprehensively under the guidance of established principles.

Skin-Interfaced Superhydrophobic Insensible Sweat Sensors for Evaluating Body Thermoregulation and Skin Barrier Functions.

Monitoring sweat rate is vital for estimating sweat loss and accurately measuring biomarkers of interest. Although various optical or electrical sensors have been developed to monitor the sensible sweat rate, the quantification of the insensible sweat rate that is directly related to body thermoregulation and skin barrier functions still remains a challenge. This work introduces a superhydrophobic sweat sensor based on a polyacrylate sodium/MXene composite sandwiched between two superhydrophobic textile layers to continuously measure sweat vapor from insensible sweat with high sensitivity and rapid response. The superhydrophobic textile on a holey thin substrate with reduced stiffness and excellent breathability allows the permeation of sweat vapor, while preventing the sensor from being affected by the external water droplets and internal sensible sweat. Integrating the insensible sweat sensor with a flexible wireless communication and powering module further yields a standalone sensing system to continuously monitor insensible sweat rates at different body locations for diverse application scenarios. Proof-of-concept demonstrations on human subjects showcase the feasibility to continuously evaluate the body's thermoregulation and skin barrier functions for the assessment of thermal comfort, disease conditions, and nervous system activity. The results presented in this work also provide a low-cost device platform to detect other health-relevant biomarkers in the sweat (vapor) as the next-generation sweat sensor for smart healthcare and personalized medicine.

Physical exercise mediates a cortical FMRP-mTOR pathway to improve resilience against chronic stress in adolescent mice.

Aerobic exercise effectively relieves anxiety disorders via modulating neurogenesis and neural activity. The molecular mechanism of exercise-mediated anxiolysis, however, remains incomplete. On a chronic restrain stress (CRS) model in adolescent mice, we showed that 14-day treadmill exercise profoundly maintained normal neural activity and axonal myelination in the medial prefrontal cortex (mPFC), in association with the prevention of anxiety-like behaviors. Further interrogation of molecular mechanisms revealed the activation of the mechanistic target of the rapamycin (mTOR) pathway within mPFC under exercise training. At the upstream of mTOR, exercise-mediated brain RNA methylation inhibited the expression of Fragile X mental retardation protein (FMRP) to activate the mTOR pathway. In summary, treadmill exercise modulates an FMRP-mTOR pathway to maintain cortical neural activity and axonal myelination, contributing to improved stress resilience. These results extended our understanding of the molecular substrate of exercise-mediated anxiolytic effect during adolescent period.

Portable electrochemiluminescence detection system based on silicon photomultiplier single photon detector and aptasensor for the detection of tetracycline in milk.

In this work, a portable electrochemiluminescence (ECL) detection system based on silicon photomultiplier (SiPM) single photon detector was proposed for the detection of ECL signals on a screen-printed electrode (SPE). This instrument innovatively used SiPM single photon detector to detect the ECL signal, which solved friability and bloat caused by the high operating voltage and the limitation of detection components in the traditional ECL detection instrument. This detection instrument showed excellent electrochemical and ECL detection performance. On this basis, an aptasensor based on silver (core)-gold (shell) bimetallic nanoparticles (Ag@AuNPs) was constructed for the detection of tetracycline (TET) in milk on SPE. Here, Ag@AuNPs had a significant effect in enhancing luminol ECL signal and immobilizing aptamer. The concentration of TET was detected according to the changes of the ECL signal intensity of the detection instrument. This instrument exhibited an excellent linearity ranging from 0.01 ng/mL to 1,000 ng/mL for the detection of TET, and a limit of detection (LOD) was 0.0053 ng/mL. The developed portable ECL detection instrument provides a new platform for the detection of small molecule contaminants.

Epidemiological Features of Klebsiella pneumoniae Infection in the Hepatobiliary System of Patients in Yantai, China, Based on Clinical and Genetic Analyses.

Purpose: To investigate the epidemiological features of Klebsiella pneumoniae infection of the hepatobiliary system of patients in Yantai, China. Methods: This retrospective study was conducted from January to December 2019 in Yantai Yuhuangding Hospital. Patients for whom K. pneumoniae was isolated from the hepatobiliary system were considered for inclusion. The clinical features and genetic analyses were conducted to explore the epidemiological characteristics. Results: A total of 88 cases were enrolled, including 69 cases of hypervirulent K. pneumoniae (hvKP) and 19 cases of classical K. pneumoniae (cKP). Community-acquired infections, fever, liver abscess, and C-reactive protein (CRP) and procalcitonin (PCT) levels were significantly higher, while biliary tract disease was lower in the hvKP group compared with the cKP group. Among the 69 hvKP infections, 61 developed a liver abscess. Community-acquired infections, fever, and CRP and PCT levels were higher, whereas biliary tract disease and malignancy were lower in the liver abscess group compared with the non-liver abscess group. All strains were susceptible to the majority of antibiotics tested. All hvKP strains possessed the bla SHV, oqxA, oqxB and fosA resistance genes. K1 and K2 accounted for 78% of hvKP strains. K1 strains belonged to sequence types ST23 and ST700, whereas K2 strains belonged to ST65, ST86 and ST5212. K1 isolates possessed the most virulence determinants, followed by K2 and non-K1/K2 isolates. K2 isolates lacked the allS gene, which was rare in non K1/K2 isolates, but present in most K1 isolates. The mceG gene was only detected in K1 isolates. AllS and virulence determinants were significantly more prevalent in the liver abscess group than in the non-liver abscess group. Conclusion: The prevalence of hvKP among K. pneumoniae infections of the hepatobiliary system is high in Yantai, China. Greater vigilance of hvKP infection is required in clinical and microbiological laboratories.

In Vitro Activity of New ß-Lactam-ß-Lactamase Inhibitor Combinations and Comparators against Clinical Isolates of Gram-Negative Bacilli: Results from the China Antimicrobial Surveillance Network (CHINET) in 2019.

Novel ß-lactam-ß-lactamase inhibitor combinations (BLBLIs) are in clinical development for the treatment of infections caused by carbapenem-resistant and difficult-to-treat resistant (DTR) (defined as resistance to all tested ß-lactams and fluoroquinolones) Gram-negative bacilli. This study evaluated the in vitro activities of cefepime-zidebactam, ceftazidime-avibactam, cefepime-tazobactam, ceftolozane-tazobactam, and other comparators against 4,042 nonduplicate Gram-negative clinical isolates collected from different regions of China (46 hospitals) in 2019. Based on the pharmacokinetic-pharmacodynamic (PK-PD) breakpoints, cefepime-zidebactam inhibited 98.5% of Enterobacterales and 98.9% of Pseudomonas aeruginosa isolates, respectively. Against carbapenem-resistant and difficult-to-treat resistant Gram-negative bacilli, cefepime-zidebactam demonstrated better activity against Enterobacterales (96% and 97.2%, respectively) and P. aeruginosa (98.2% and 96.9%, respectively). Among the 379 carbapenem-resistant Enterobacterales isolates, the most common carbapenemase genes detected were blaKPC-2 (64.1%) and blaNDM (30.9%). Cefepime-zidebactam showed an MIC90 of ≤2 mg/L for 98.8% of blaKPC-positive isolates and 89.7% of blaNDM-positive isolates. Ceftazidime-avibactam also showed efficient in vitro activity against Enterobacterales (93.6%) and P. aeruginosa (87.7%). Ceftazidime-avibactam was active against 97.5% of blaKPC-positive isolates and 100% of blaOXA-232-positive isolates. Cefepime-zidebactam inhibited 97.3% of Acinetobacter baumannii isolates with an MIC50/90 of 16/32 mg/L. Our study systematically evaluated the in vitro activities of these new BLBLIs against a variety of Gram-negative bacilli, provided preclinical data for the approval of these BLBLIs in China, and supported cefepime-zidebactam and ceftazidime-avibactam as potential efficient therapies for infections caused by carbapenem-resistant Enterobacterales (CRE), carbapenem-resistant P. aeruginosa (CRPA), and DTR isolates. IMPORTANCE Enterobacterales, Pseudomonas aeruginosa, and Acinetobacter baumannii are the most common Gram-negative bacilli to cause nosocomial infections throughout the world. Due to their large public health and societal implications, carbapenem-resistant A. baumannii (CRAB), carbapenem-resistant P. aeruginosa (CRPA), and carbapenem-resistant and third-generation-cephalosporin-resistant Enterobacteriaceae were regarded by the World Health Organization (WHO) as a global priority for investment in new drugs in 2017. The present study showed the potent in vitro activity of these novel BLBLIs and other comparators against Gram-negative bacillus isolates, including carbapenem-resistant or difficult-to-treat resistant phenotypes. Polymyxins, tigecycline, and ceftazidime-avibactam (except for blaNDM-positive isolates) were available for the treatment of infections caused by CRE isolates. Currently, cefepime-zidebactam and other BLBLIs have not yet been approved for use in China. Here, our study aimed to evaluate the in vitro activities of BLBLIs against Gram-negative bacillus isolates, especially CRE, before clinical use.

Physical Exercise Prevented Stress-Induced Anxiety via Improving Brain RNA Methylation.

Physical exercise is effective in alleviating mental disorders by improving synaptic transmission; however, the link between body endurance training and neural adaptation has not yet been completely resolved. In this study, the authors investigated the role of RNA N6 -methyladenosine (m6A), an emerging epigenetic mechanism, in improved resilience against chronic restraint stress. A combination of molecular, behavioral, and in vivo recording data demonstrates exercise-mediated restoration of m6A in the mouse medial prefrontal cortex, whose activity is potentiated to exert anxiolytic effects. Furthermore, it is revealed that hepatic biosynthesis of one methyl donor is necessary for exercise to improve brain RNA m6A to counteract environmental stress. This novel liver-brain axis provides an explanation for brain network changes upon exercise training and provides new insights into the diagnosis and treatment of anxiety disorders.

Novel sandwich-type electrochemiluminescence aptasensor based on luminol functionalized aptamer as signal probe for kanamycin detection.

A novel sandwich electrochemiluminescence (ECL) aptasensor was developed for highly sensitive detection of kanamycin using luminol-functionalized aptamer as a signal probe. The aptasensor used polyethyleneimine (PAMAM), molybdenum disulfide, and multi-walled carbon nanotubes as the substrate, which provided enough binding sites for aptamer1 (the aptamer which modified NH2) coupling. We found that kanamycin could be detected using the aptamer1 containing the same base sequence as aptamer2 (the aptamer which modified SH) on the electrode self-assembly. In addition, PAMAM nanocomposites can be used to effectively improve the ECL intensity by loading a high volume of luminol molecules and silver nanoparticles. In the presence of kanamycin, the sandwiched aptasensor was formed between aptamer1 and the probe of aptamer2 connecting silver nanoparticles, luminol, and PAMAM, resulting in a proportional increase of ECL intensity. Since the significantly enhanced loading of luminol by PAMAM accelerated the electron transfer, the sensitive aptasensor exhibited a wide linear range of detection from 1 × 10-3 to 1 × 103 ng/mL and a low detection limit of 0.21 pg/mL (S/N) for kanamycin. The fabricated aptasensor was successfully applied in quantitative analysis of kanamycin in milk samples.

Diminished Susceptibility to Cefoperazone/Sulbactam and Piperacillin/Tazobactam in Enterobacteriaceae Due to Narrow-Spectrum ß-Lactamases as Well as Omp Mutation.

Cefoperazone/sulbactam (CSL) and piperacillin/tazobactam (TZP) are commonly used in clinical practice in China because of their excellent antimicrobial activity. CSL and TZP-nonsusceptible Enterobacteriaceae are typically resistant to extended-spectrum cephalosporins such as ceftriaxone (CRO). However, 11 nonrepetitive Enterobacteriaceae strains, which were resistant to CSL and TZP yet susceptible to CRO, were collected from January to December 2020. Antibiotic susceptibility tests and whole-genome sequencing were conducted to elucidate the mechanism for this rare phenotype. Antibiotic susceptibility tests showed that all isolates were amoxicillin/clavulanic-acid resistant and sensitive to ceftazidime, cefepime, cefepime/tazobactam, cefepime/zidebactam, ceftazidime/avibactam, and ceftolozane/tazobactam. Whole-genome sequencing revealed three of seven Klebsiella pneumoniae strains harbored bla SHV-1 only, and four harbored bla SHV-1 and bla TEM-1B. Two Escherichia coli strains carried bla TEM-1B only, while two Klebsiella oxytoca isolates harbored bla OXY-1-3 and bla OXY-1-1, respectively. No mutation in the ß-lactamase gene and promoter sequence was found. Outer membrane protein (Omp) gene detection revealed that numerous missense mutations of OmpK36 and OmpK37 were found in all strains of K. pneumoniae. Numerous missense mutations of OmpK36 and OmpK35 and OmpK37 deficiency were found in one K. oxytoca strain, and no OmpK gene was found in the other. No Omp mutations were found in E. coli isolates. These results indicated that narrow spectrum ß-lactamases, TEM-1, SHV-1, and OXY-1, alone or in combination with Omp mutation, contributed to the resistance to CSL and TZP in CRO-susceptible Enterobacteriaceae. Antibiotic susceptibility tests Antibiotics Breakpoint, (µg/ml) Klebsiella pneumoniae Escherichia cou Klebriehd axyoca E1 E3 E4 E7 E9 E10 E11 E6 E8 E2 E5 CRO ≤1≥4 ≤0.5 ≤0.5 ≤0.5 ≤0.5 1 ≤0.5 1 ≤0.5 ≤0.5 1 1 CAZ 4 ≥16 1 2 1 4 4 4 4 2 4 1 1 FEP ≤2 216 1 1 0.25 1 2 2 2 0.5 2 1 1 AMC ≤8 ≥32 ≥128 ≥128 ≥128 ≥128 ≥128 ≥128 ≥128 ≥128 ≥128 ≥128 ≥128 CSL ≤16 ≥64 64 64 64 64 ≥128 128 ≥128 64 128 128 ≥128 TZP ≤16 ≥128 ≥256 ≥256 ≥256 ≥256 2256 2256 ≥256 ≥256 ≥256 ≥256 ≥256 FPT ≤2 ≥16 1 0.5 0.06 0.125 2 1 2 0.25 1 0.125 0.25 FPZ ≤2 216 0.25 0.25 0.06 0.125 0.25 0.25 1 0.125 0.25 0.125 0.125 CZA ≤8 216 1 0.5 0.25 0.25 1 0.25 1 0.5 0.5 0.5 0.25 CZT ≤2 28 2 1 0.5 1 2 2 2 1 1 2 2 CROceftriaxone, CAZceftazidime, FEPcefepime, AMC:amoxicillin clavulanic-acid, CSLcefoperazone/sulbactam, TZP:piperadllin/tazobactam, FPT:cefepime tazobactam, FPZ:cefepime/zidebactam, CZA:ceftazidime/avibactam, CZTceftolozane/tazobactam Gene sequencing results Number Strain ST p-Lactamase gene Promoter sequence mutation Omp mutation El Kpn 45 blaSHV-1, blaTEM-lB none OmpK36, OmpK3 7 E3 Kpn 45 blaSHV-1, blaTEM-lB none OmpK36. OmpK3 7 E4 Kpn 2854 blaSHV-1 none OmpK36, OmpK3 7 E7 Kpn 2358 blaSHV-1 - blaTEM-lB none OmpK36, OmpK3 7 E9 Kpn 2358 blaSHV-1. blaTEM-lB none OmpK36. OmpK3 7 E10 Kpn 18 9 blaSHV-1 none OmpK36. OmpK3 7 Ell Kpn 45 blaSHV-1 none OmpK36, OmpK3 7 E6 Eco 88 blaTEM-lB none none ES Eco 409 blaTEM-1B none none E2 Kox 194 blaOXY-1-3 none OmpK36 mutations. OmpK35 and OmpK 37 deficiency E5 Kox 11 blaOXY-1-1 none no OmpK (OmpK3 5, OmpK36 and OmpK37) gene found.

Clinical Effect of Bushen Huoxue Method Combined with Platelet-Rich Plasma in the Treatment of Knee Osteoarthritis and Its Effect on IL-1, IL-6, VEGF, and PGE-2.

Objective: To observe the clinical efficacy of the Bushen Huoxue method combined with platelet-rich plasma (PRP) in the treatment of knee osteoarthritis (KOA) and its effect on serum and joint fluid interleukin-1 (IL-1), interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), and prostaglandin E2 (PGE-2). Methods: A total of 64 cases of KOA diagnosed and treated from January 2020 to January 2021 were randomly divided into research group and control group, with 32 cases in each group. The control group was treated with PRP, and the research group took the prescription of the Bushen Huoxue method on the basis of the control group. The clinical efficacy was assessed according to the criteria in "the diagnosis and Treatment of osteoarthritis," osteoarthritis index score and pain visual analogue score (VAS). Serum and articular fluid VAS, IL-1, IL-6, VEGF, and PGE-2 levels were detected by the enzyme-linked immunosorbent assay (ELISA). Results: The clinical effective rate of the research group was 93.8%, which was significantly higher than that of the control group (90.6%). There was no significant difference in the scores of osteoarthritis index between the two groups before treatment, but the scores of both groups decreased after treatment and was lower in the research group than those in the control group. VAS was significantly decreased in two groups after treatment and it was lower in the research group than that in the control group. After treatment, the levels of IL-1, IL-6, and PGE-2 in serum and articular fluid all indexes were decreased, and the levels in the research group were lower than those in the control group. Conclusions: PRP joint cavity injection combined with oral administration of Bushen Huoxue prescription, and PRP joint cavity injection alone can improve the efficacy of KOA, relieve knee pain, and promote the recovery of knee function. The mechanism may be related to the reduction of IL-1, IL-6, VEGF levels, and PGE-2 levels in the serum and joint fluid. However, the efficacy of combination therapy was superior to PRP alone.

Non-immobilized GO-SELEX of aptamers for label-free detection of thiamethoxam in vegetables.

Due to the massive use of thiamethoxam (TMX) pesticide and the accumulated potential hazards exposure, the detection of TMX is of great significance to food and ecological safety. In this study, aptamers with affinity for TMX were obtained through graphene oxide assisted systematic evolution of ligands by exponential enrichment (GO-SELEX). After 9 rounds of positive and counter selection, 5 candidate sequences were obtained, among which seq.20 had the highest affinity for TMX, and its dissociation constant (Kd) was 210.47 ± 79.37 nM. Then, the aptamer was further truncated based on structural analysis. The truncated aptamers (seq.20-1, seq.20-2) exhibited higher affinity (Kd = 118.34 ± 13.85 nM, Kd = 123.35 ± 29.80 nM), which seq.20-2 had only 37 bases. Furthermore, circular dichroism spectroscopy showed that TMX induced the conformation of aptamer from B-form structure to hairpin structure, and then formed a stable TMX-ssDNA complex. Finally, the truncated aptamer (seq.20-2) and the original aptamer (seq.20) were used as recognition elements to construct colorimetric aptasensors based on gold nanoparticles for the detection of TMX. It was found that the sensitivity of the former (LOD = 1.67 ± 0.12 nM, S/N = 3) was better than that of the latter (LOD = 3.33 ± 0.23 nM, S/N = 3). Feasibility of truncated aptamer as recognition element in the detection of TMX in vegetable samples was preliminarily verified.

A novel label-free electrochemiluminescence aptasensor using a tetrahedral DNA nanostructure as a scaffold for ultrasensitive detection of organophosphorus pesticides in a luminol-H2O2 system.

In this work, a new type of Au-tetrahedral DNA nanostructure (Au-TDN) was originally proposed and successfully applied in an electrochemiluminescence aptasensor to detect organophosphorus pesticides (Ops). The aptamers modified with -SH could be covalently bonded with gold nanoparticles (AuNPs) to form a tetrahedron structure, and there were independent probes at each vertex of the tetrahedron, which could increase the probability of specific binding with Ops. The originally designed structure could not only maintain a stable tetrahedral configuration, but also combined with the target to improve the sensitivity of the sensor. Meanwhile, silver nanoparticles (AgNPs) could catalyze the chemical reaction between luminol and H2O2 to generate a variety of intermediates called reactive oxygen species (ROS) for signal enhancement. Factors that had important influences on the aptasensor, such as the concentration of Au-TDN, the incubation time, and the pH value of the buffer, were optimized in this trial. According to the final results, the limit of detection (LOD) of 3 pg mL-1 (S/N = 3) for methyl parathion, the LOD of 0.3 pg mL-1 (S/N = 3) for parathion and the LOD of 0.03 pg mL-1 (S/N = 3) for phoxim were obtained, respectively. Moreover, the novel tetrahedral structure could be replaced by different types of aptamers to expand its application range and lay a foundation for the development of portable rapid detection devices for pesticide residues.

Human-like performance umami electrochemical biosensor by utilizing co-electrodeposition of ligand binding domain T1R1-VFT and Prussian blue.

Over the past decades, due to the desire for artificial umami flavors, apparatuses for detecting the umami taste have constantly been developed. Nevertheless, most information on umami is still acquired through human sensory assessment, which makes it difficult to establish an umami standard or quantify the umami flavor. In this study, the ligand binding domain called venus flytrap (VFT) domain of the umami taste receptor protein T1R1 was used as a recognition element, and an electrochemical biosensor based on a double-signal amplification strategy was constructed using single-walled carbon nanotubes (SWCNTs) and Prussian blue (PB). Moreover, the umami taste of four representative umami substances, inosine-5'-monophosphate (IMP), monosodium L-glutamate (MSG), beefy meaty peptide (BMP), and sodium succinate (WSA), were successfully quantitatively measured using differential pulse voltammetry (DPV) at an electrochemical workstation. Based on an equation (S/N = 3), the low detection limits (LODs) of IMP, MSG, BMP, and WSA were 0.1, 0.1, 0.1, and 0.01 pM, respectively. Meanwhile, a normalized signal intensity of more than 90% was kept for 4 days. The results showed that the biosensor could be used to detect umami substances with high sensitivity and selectivity, and was shown to have human-like performance. To develop the T1R1-VFT biosensor using the above-mentioned method, we utilized the ligand binding domain of the human umami receptor, rather than the entire umami receptor protein, which had a complex structure, having the following advantages: volume reduction, simplicity, and stability. This method has great potential for the detection of umami tastes, instead of using sensory evaluation, and for the development of new artificial flavorings.

A novel electrochemiluminescence aptasensor based on copper-gold bimetallic nanoparticles and its applications.

In this work, a novel electrochemiluminescence (ECL) aptasensor was structured for the detection of four organophosphorus pesticides (OPs). Firstly, multi-walled carbon nanotubes (MWCNTs) were used to create a favorable loading interface for the fixation of tris (2, 2'-bipyridyl) ruthenium (II) (Ru (bpy)32+). At the same time, copper (core)-gold (shell) bimetallic nanoparticles (Cu@Au NPs) were synthesized in the aqueous phase for the sensor construction. Gold nanoparticles (Au NPs) could promote the electrochemiluminescence intensity of Ru (bpy)32+ with high efficiency by catalyzing the oxidation process of tri-n-propylamine (TPrA). Compared with the Au NPs, Cu@Au NPs increased the solid loading of Au NPs by virtue of the large specific surface area of copper nanoparticles (Cu NPs), which could further improve the sensitivity of aptasensor. When OPs were added, the ECL intensity was significantly reduced, and the concentration of OPs could be detected through the ECL intensity. Under the optimum conditions, the aptasensor had a wider dynamic range and ultra-low detection limit for the detection of four pesticides: profenofos, isocarbophos, phorate, and omethoate, and their detection limits were 3 × 10-4 ng/mL, 3 × 10-4 ng/mL, 3 × 10-3 ng/mL, and 3 × 10-2 ng/mL respectively (S/N = 3). The aptasensor had the merits of good stability, reproducibility, and specificity, and had a favorable recovery rate in detecting OPs residues in vegetables. This work provided an effective method for the construction of a simple, rapid, and sensitive biosensor.