Comparative proteomics study of exosomes in Vibrio harveyi and Vibrio anguillarum.

Exosomes are a class of extracellular vesicles released by bacteria and contain diverse biomolecules. In this study, we isolated exosomes from Vibrio harveyi and Vibrio anguillarum, which are both serious pathogens in mariculture, using a supercentrifugation method, and the proteins in the exosomes of these two vibrios were analyzed by LC-MS/MS proteomics. Exosome proteins released by V. harveyi and V. anguillarum were different; they not only contained virulence factors (such as lipase and phospholipase in V. harveyi, metalloprotease and hemolysin in V. anguillarum), but also participated in the important life activities of bacteria (such as fatty acid biosynthesis, biosynthesis of antibiotics, carbon metabolism). Subsequently, to verify whether the exosomes participated in bacterial toxicity, after Ruditapes philippinarum was challenged with V. harveyi and V. anguillarum, the corresponding genes of virulence factors from exosomes screened by proteomics were tested by quantitative real-time PCR. All the genes detected were upregulated which suggested that exosomes were involved in vibrio toxicity. The results could provide an effective proteome database for decoding the pathogenic mechanism of vibrios from the exosome perspective.

Development and validation of MRI-based radiomics signatures models for prediction of disease-free survival and overall survival in patients with esophageal squamous cell carcinoma.

OBJECTIVES: To develop and validate an optimal model based on the 1-mm-isotropic-3D contrast-enhanced StarVIBE MRI sequence combined with clinical risk factors for predicting survival in patients with esophageal squamous cell carcinoma (ESCC). METHODS: Patients with ESCC at our institution from 2015 to 2017 participated in this retrospective study based on prospectively acquired data, and were randomly assigned to training and validation groups at a ratio of 7:3. Random survival forest (RSF) and variable hunting methods were used to screen for radiomics features and LASSO-Cox regression analysis was used to build three models, including clinical only, radiomics only and combined clinical and radiomics models, which were evaluated by concordance index (CI) and calibration curve. Nomograms and decision curve analysis (DCA) were used to display intuitive prediction information. RESULTS: Seven radiomics features were selected from 434 patients, combined with clinical features that were statistically significant to construct the predictive models of disease-free survival (DFS) and overall survival (OS). The combined model showed the highest performance in both training and validation groups for predicting DFS ([CI], 0.714, 0.729) and OS ([CI], 0.730, 0.712). DCA showed that the net benefit of the combined model and of the clinical model is significantly greater than that of the radiomics model alone at different threshold probabilities. CONCLUSIONS: We demonstrated that a combined predictive model based on MR Rad-S and clinical risk factors had better predictive efficacy than the radiomics models alone for patients with ESCC. KEY POINTS: • Magnetic resonance-based radiomics features combined with clinical risk factors can predict survival in patients with ESCC. • The radiomics nomogram can be used clinically to predict patient recurrence, DFS, and OS. • Magnetic resonance imaging is highly reproducible in visualizing lesions and contouring the whole tumor.

A novel method for determining relative response factors using high-performance liquid chromatography with photodiode array detector and evaporative light scattering detection.

OBJECTIVES: Because the purity of the two impurities reference standard (RS) of cefathiamidine is not easy to obtain, HPLC-PDA-ELSD were used to determin the RRFs of cefathiamidine impurities. METHODS: Peak area correction was applied to calculate RRFs to eliminate the influence of different responses caused by the difference in pH between the two mobile phases of HPLC-PDA and HPLC-PDA-ELSD. The resulting RRF values have been verified by qNMR. CONCLUSION: The new calcution method described in this article provides a reliable research idea for determintion the RRFs by HPLC-PDA-ELSD, especially when the purity of RS is unknown and the mobile phase of HPLC-PDA and HPLC-PDA-ELSD have difference. This method can be mutually verified with qNMR to ensure the accuracy of RRFs. It is also promingsing replace determination RRF by qNMR becausing economical, simple and low cost.

Multi-residue method for the detection of 40 ß-lactam-antibiotics in vaccines by LC-MS/MS.

Antibiotics are widely used to treat bacterial infections during the process of vaccine production and storage resulting in antibiotic residues that can cause serious harm. A simple and sensitive method for residue analysis of 40 ß-lactam antibiotics was developed and validated for vaccines including inactivated enterovirus 71 vaccine (Vero cells), recombinant hepatitis B vaccine (Saccharomyces cerevisiae), and live attenuated varicella vaccine using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI- MS/MS). Samples were prepared with acetonitrile as the protein precipitant. LC separation was performed on a C18 column. These analytes were determined by LC-MS/MS operating multiple-reaction monitoring (MRM) scans in positive mode. The ranges for limits of detection (LOD) and quantification (LOQ) were as follows: 0.02-4 ng/dose (S/N ≥ 3) and 0.04-10 ng/dose in inactivated enterovirus 71 vaccine (Vero cells) and recombinant hepatitis B vaccine (Saccharomyces cerevisiae), 0.04-16 ng/dose and 0.2-20 ng/dose in live attenuated varicella vaccine. The ranges of recoveries of all antibiotics were 84.5%-108.2% in inactivated enterovirus 71 vaccine (Vero cells), 73%-108% in recombinant hepatitis B vaccine (Saccharomyces cerevisiae), and mostly 68.2%-107.8% in live attenuated varicella vaccine. This method simultaneously offers qualitative and quantitative analysis of multi-antibiotics in vaccines, which improves vaccine safety.

A colorimetric aptasensor for the simple and rapid detection of human papillomavirus type 16 L1 proteins.

In this study, a novel colorimetric aptasensor was developed for the rapid detection and visual screening of HPV16 L1 proteins using gold nanoparticles (AuNPs) and an RNA aptamer against HPV16 L1 protein (APTHPV16 L1). The AuNP-APTHPV16 L1 conjugates could be aggregated by the addition of a salt in the presence of HPV16 L1 proteins at the ppb level. At the same time, the surface plasma resonance absorption peaks of AuNPs shifted to a short wavelength, and an observable change in color from red to blue occurred. The relative absorbance (Ablank - Asample/Ablank) at 520 nm exhibited a stable response to HPV16 L1 proteins over a concentration range from 9.6 to 201.6 ng mL-1. The visual detection limit of HPV16 L1 proteins was found to be 9.6 ng mL-1. Finally, the proposed colorimetric aptasensor was successfully applied for the rapid and effective detection of HPV16 L1 proteins in clinical samples and vaccine samples. The validity and reliability of the proposed colorimetric aptasensor were verified by the enzyme-linked immunosorbent assay method. The proposed colorimetric aptasensor provided a promising indicator for screening and quantitative detection of HPV16 L1 proteins in clinical samples.

Synstable Fusion: A Network-Based Algorithm for Estimating Driver Genes in Fusion Structures.

Gene fusion structure is a class of common somatic mutational events in cancer genomes, which are often formed by chromosomal mutations. Identifying the driver gene(s) in a fusion structure is important for many downstream analyses and it contributes to clinical practices. Existing computational approaches have prioritized the importance of oncogenes by incorporating prior knowledge from gene networks. However, different methods sometimes suffer different weaknesses when handling gene fusion data due to multiple issues such as fusion gene representation, network integration, and the effectiveness of the evaluation algorithms. In this paper, Synstable Fusion (SYN), an algorithm for computationally evaluating the fusion genes, is proposed. This algorithm uses network-based strategy by incorporating gene networks as prior information, but estimates the driver genes according to the destructiveness hypothesis. This hypothesis balances the two popular evaluation strategies in the existing studies, thereby providing more comprehensive results. A machine learning framework is introduced to integrate multiple networks and further solve the conflicting results from different networks. In addition, a synchronous stability model is established to reduce the computational complexity of the evaluation algorithm. To evaluate the proposed algorithm, we conduct a series of experiments on both artificial and real datasets. The results demonstrate that the proposed algorithm performs well on different configurations and is robust when altering the internal parameter settings.

[Study on method of laparoscopic training based on eye gaze tracking techniques].

In current domestic research on laparoscopic training, researchers usually consider instrument movement path in the hand-eye coordination relationship. However, they ignore the information contained in visual cues by which could guide and control instrument movements. Studies in other areas have shown that trainers can improve their perceptual-motor skills by gaze training. This paper was designed to examine the effectiveness of eye gaze tracking technology in laparoscopic training and to analyze gaze strategy of the subjects in different training methods. The Tobii X1 Light Eye Tracker was used to track the gaze position of subjects when they were performing the two-handed transferring task in box trainer, and to obtain parameters related to gaze strategy including the efficiency of task completion, as well as visual search, visual processing and observation transfer analysis based on Markov chain model. The results showed that the completion time during the last training in gaze training group was decreased by 101.5 s comparing to the first training. Compared with video training group, gaze strategy of gaze training group has a significant change, such as fixation and saccade duration rate was increased by 38%, fixation duration on target area was increased, and saccade amplitude increased by 0.58°, and the probability of the fixation point transferring to equipment decreased by 15%. The results demonstrated that eye gaze tracking technology can be used in laparoscopic training, and can improve the subjects' skills and shorten the learning curve by learning gaze strategies of experts.

[Assessment of laparoscopic training based on eye tracker and electroencephalograph].

The aim of this study is to evaluate the effect of laparoscopic simulation training with different attention. Attention was appraised using the sample entropy and θ/ß value, which were calculated according to electroencephalograph(EEG) signal collected with Brain Link. The effect of laparoscopic simulation training was evaluated using the completion time, error number and fixation number, which were calculated according to eye movement signal collected with Tobii eye tracker. Twenty volunteers were recruited in this study. Those with the sample entropy lower than0.77 were classified into group A and those higher than 0.77 into group B. The results showed that the sample entropy of group A was lower than that of group B, and fluctuations of A were more steady. However, the sample entropy of group B showed steady fluctuations in the first five trainings, and then demonstrated relatively dramatic fluctuates in the later five trainings. Compared with that of group B, the θ/ß value of group A was smaller and shows steady fluctuations. Group A has a shorter completion time, less errors and faster decrease of fixation number. Therefore, this study reached the following conclusion that the attention of the trainees would affect the training effect. Members in group A, who had a higher attention were more efficient and faster training. For those in group B, although their training skills have been improved, they needed a longer time to reach a plateau.

Application of improved and efficient image repair algorithm in rock damage experimental research.

In the petroleum and coal industries, digital image technology and acoustic emission technology are employed to study rock properties, but both exhibit flaws during data processing. Digital image technology is vulnerable to interference from fractures and scaling, leading to potential loss of image data; while acoustic emission technology is not hindered by these issues, noise from rock destruction can interfere with the electrical signals, causing errors. The monitoring errors of these techniques can undermine the effectiveness of rock damage analysis. To address this issue, this paper focuses on the restoration of image data acquired through digital image technology, leveraging deep learning techniques, and using soft and hard rocks made of similar materials as research subjects, an improved Incremental Transformer image algorithm is employed to repair distorted or missing strain nephograms during uniaxial compression experiments. The concrete implementation entails using a comprehensive training set of strain nephograms derived from digital image technology, fabricating masks for absent image segments, and predicting strain nephograms with full strain detail. Additionally, we adopt deep separable convolutional networks to optimize the algorithm's operational efficiency. Based on this, the analysis of rock damage is conducted using the repaired strain nephograms, achieving a closer correlation with the actual physical processes of rock damage compared to conventional digital image technology and acoustic emission techniques. The improved incremental Transformer algorithm presented in this paper will contribute to enhancing the efficiency of digital image technology in the realm of rock damage, saving time and money, and offering an innovative approach to traditional rock damage analysis.

A method to improve the prediction performance of cancer-gene association by screening negative training samples through gene network data.

This work focuses on data sampling in cancer-gene association prediction. Currently, researchers are using machine learning methods to predict genes that are more likely to produce cancer-causing mutations. To improve the performance of machine learning models, methods have been proposed, one of which is to improve the quality of the training data. Existing methods focus mainly on positive data, i.e. cancer driver genes, for screening selection. This paper proposes a low-cancer-related gene screening method based on gene network and graph theory algorithms to improve the negative samples selection. Genetic data with low cancer correlation is used as negative training samples. After experimental verification, using the negative samples screened by this method to train the cancer gene classification model can improve prediction performance. The biggest advantage of this method is that it can be easily combined with other methods that focus on enhancing the quality of positive training samples. It has been demonstrated that significant improvement is achieved by combining this method with three state-of-the-arts cancer gene prediction methods.

Influence of Light Irradiation on the Degradation of Dezocine in Injections.

Dezocine, which is well-known as an analgesic, had about 45% share of the Chinese opioid analgesic market. Since drug products containing impurities could bring serious health consequences, it was important to control the generation of impurities and degradation products in the dezocine product. In this study, two kinds of photodegradation products (i.e., degradation product 1 and degradation product 2) in the dezocine injection were isolated using high-performance liquid chromatography. The possible structures of the photodegradation products were identified using both high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy. In addition, the possible generation mechanism showed that degradation product 1 was the oxidation product of dezocine, and degradation product 2 was the coupled dimer of dezocine. Finally, we found that the degradation rate of dezocine increased with the increase in light intensity. Moreover, the degradation of dezocine easily occurred under ultraviolet light in comparison with visible light. A deeper insight into the generation of the photodegradation products in the dezocine injection would directly contribute to the safety of drug therapy based on the dezocine injection by minimizing the degradant/impurity-related adverse effects of drug preparations.

The improvement and verification of fluid dynamics simulation on temperature uniformity during heat treatment of ring pieces.

The improvement and verification of fluid dynamics simulation on temperature uniformity during the heat treatment of ring pieces are investigated in this study. The accuracy of the temperature field model is validated by comparing the simulation results with the measured temperatures. The findings reveal that the vortex generated near the furnace wall during heat treatment significantly affects the uniformity of the temperature field. To improve this, adjustments are made to the placement of ring pieces based on an experimentally validated fluid dynamics simulation model, and subsequent calculations are performed on this adjusted model. It is observed that these adjustments greatly enhance temperature uniformity in the heating process, with a 39.06 % improvement in medium-temperature zone (732.32-743.69 k) within the furnace compared to the original model. Additionally, surface temperatures of ring pieces in another medium-temperature zone (668.89-691.11 k) show a 34.54 % improvement in comparison to those predicted by the original model.

The acute neurotoxicity of inorganic mercury in Mactra chinensis philippi.

Inorganic mercury (IHg) is hazardous to marine organisms especially resulting in neurotoxicity, bivalves are sensitive to pollutants as "ocean sentinel", but data on the neurotoxicity of IHg in bivalves are sparse. So we chosed M. chinensis philippi with typical neural structures in bivalves to investigate the neurotoxicity of IHg, which could be helpful to understand the specificity of neural regulation and the response characteristics of bivalves. After acute exposed to IHg (HgCl2) for 24 h, the metabolites of ganglion tissues in M. chinensis philippi were evaluated using 1H-nuclear magnetic resonance based metabolomics; Ca2+, neurotransmitters (nitric oxide, glutamate, acetylcholine) and related enzymes (calcineurin, nitric oxide synthase and acetylcholinesterase) were measured using biochemical detection. Compared to the control group, the levels of the nitric oxide (81.04 ± 12.84 µmol/g prot) and acetylcholine (30.93 ± 12.57 µg/mg prot) in M. chinensis philippi of IHg-treated were decreased, while glutamate (2.11 ± 0.61 mmol/L) increased significantly; the activity of nitric oxide synthase (679.34 ± 135.33 U/mg prot) was increased, while acetylcholinesterase (1.39 ± 0.44 U/mg prot) decreased significantly, and the activity of calcineurin (0.52 ± 0.02 U/mg prot) had a statistically insignificant increasing tendency. The concentration of Ca2+ (0.92 ± 0.46 mmol/g prot) in the IHg-treated group was significantly higher than that in the control group. OPLS-DA was performed to reveal the difference in metabolites between the control and IHg-challenged groups, the metabolites of glucose, glutamine, inosine, succinate, glutamate, homarine, and alanine were sensitive to IHg, subsequently metabolic pathways that were affected including glucose metabolism, glutamine metabolism, nucleotide metabolism, Krebs cycle, amino acid metabolism and osmotic regulation. In our study, IHg interfered with metabolites in M. chinensis philippi, thus the corresponding metabolic pathways were changed, which influenced the neurotransmitters subsequently. Furthermore, Ca2+overload affected the synthesis or degradation of the neurotransmitters, and then the altered neurotransmitters involved in changes in metabolic pathways again. Overall, we hypothesized that the neurotoxic effects of IHg on bivalve were in close contact with metabolism, neurotransmitters, related enzymes and Ca2+, which could be effective neurotoxic biomarkers for marine environmental quality assessment, and also provide effective data for the study of the regulatory mechanism of the nervous system in response to IHg in bivalves.

Toxic effects of ZnO NPs on immune response and tissue pathology in Mytilus galloprovincialis.

Nano-zinc oxide (ZnO NPs), as widely used nanomaterials, are inevitably released into aquatic environments, posing potential threats to aquatic organisms. Mytilus galloprovincialis is a bivalve species sensitive to changes in marine ecological environments, but there has been limited research on its toxicity response to ZnO NPs. Therefore, we selected M. galloprovincialis as the research subject and exposed them to 50 µg/L ZnO NPs for 96 h and 30 days to determine the dissolution of ZnO NPs in seawater and their distribution in M. galloprovincialis. The toxicity of ZnO NPs in M. galloprovincialis was then evaluated through gene expression, tissue pathology, and cellular immune response. The results showed that ZnO NPs could enrich Zn in various tissues of the mussel, in the order of gills > hepatopancreas > adductor muscle > mantle. Seven immune-related genes including four heat shock protein genes (HSPA12A, sHSP24.1, sHSP22, TCTP) and three apoptotic genes (Ras, p63 and Bcl-2) were altered to varying degrees. There was a downward trend in lysosomal membrane stability of M. galloprovincialis after exposure to ZnO NPs for 96 h and 30 days, while ROS and apoptosis rates increased significantly. Furthermore, the seven genes, apoptosis, LMS, and ROS were dependent on exposure time, treatment, and their interaction. Histopathological damage included disorganisation of hepatopancreas epithelial cells, gill filament swelling, and contraction of blood sinuses. These results indicated that ZnO NPs exerted toxicity in M. galloprovincialis, affecting the immune system, resulting in changes in the expression of immune-related genes and ultimately leading to histopathological changes. Our research findings could contribute to systematically understand the impact of ZnO NPs on bivalves in aquatic environments and provide a theoretical basis for marine pollution assessment.

Single-injection serratus anterior plane block for cardiothoracic surgery via thoracotomy in children: a systematic review and meta-analysis of randomised controlled trials.

BACKGROUND: Serratus anterior plane block (SAPB) has gained popularity in cardiothoracic surgery due to its feasibility and simplicity. However, the efficacy of ultrasound-guided single-injection SAPB in the paediatric population has not been well evaluated, as only a few studies with small sample sizes are available. METHODS: We searched PubMed, Embase (Ovid), Cochrane Central Register of Controlled Trials, Wanfang databases and China National Knowledge Infrastructure from their inception to 31 September 2022 for randomised comparative clinical trials that compared single-injection SAPB with systemic analgesia or different forms of regional analgesia in children. The primary outcomes included postoperative opioid consumption and pain scores within 24 hours. The secondary outcomes included postoperative adverse events, the need for rescue analgesia and the time from the end of surgery to endotracheal tube removal. RESULTS: Five randomised controlled trials with 418 children meeting the inclusion criteria were included. SAPB markedly reduced postoperative opioid consumption up to 24 hours compared with controls (mean difference (MD): -0.29 mg/kg, 95% CI -0.38 to -0.20, I 2 =67%]. The postoperative pain scores were reduced compared with controls: 1 hour (MD -0.6, 95% CI -1.17 to -0.04, I 2 =92%), 4-6 hours (MD -1.16, 95% CI -1.87 to -0.45, I 2 =90%) and 12 hours (MD -0.71, 95% CI -1.35 to -0.08, I 2 =86%). The incidence of postoperative nausea and vomiting was comparable between SAPB and controls. One trial suggested that the analgesic effect of SAPB was comparable to that of ICNB (intercostal nerve block). CONCLUSION: Single-injection SAPB is associated with a reduction in opioid consumption and pain intensity after cardiothoracic surgery via thoracotomy in children. Due to the high heterogeneity, the Grading of Recommendations Assessment, Development and Evaluation scores were low. Clinical trials with rigorous methodological approaches as well as safety endpoints are needed to confirm these preliminary findings. PROSPERO REGISTRATION NUMBER: CRD42021241691.

Comparing postoperative analgesia of bilateral serratus anterior plane block and thoracic paravertebral block for children following the Nuss procedure: protocol for a randomised, double-blind, non-inferiority clinical trial.

INTRODUCTION: The Nuss procedure, despite being a minimally invasive surgery, is regarded as one of the most painful surgical procedures in children, and postoperative pain control remains a major clinical issue in this population. Thoracic paravertebral nerve block (TPVB) is reported as excellent pain relief for the Nuss procedure despite its challenging performance and associated adverse effects. Serratus anterior plane block (SAPB) is a simplified and effective method for managing thoracic pain as an alternative to TPVB. However, whether SAPB can provide analgesia comparable with that provided by the TPVB approach in children undergoing the Nuss procedure is unknown. METHODS AND ANALYSIS: This will be a prospective, randomised, double-blind, single-centre, non-inferiority trial that will enrol children aged 7-16 years subjected to the Nuss operation for pectus excavatum. In total, 74 paediatric patients will be randomly assigned to either the SAPB or TPVB group after general anaesthesia to receive ultrasound-guided regional nerve blocks (0.25% ropivacaine 2.5 mg/kg). The primary outcome will be the assessment of postoperative pain intensity at predetermined time points. The secondary outcomes will include assessing intraoperative opioid intake, consumption of analgesics within 24 hours postoperatively, time of first use of rescue analgesics, extubation time, perioperative adverse events and plasma ropivacaine concentrations across the block groups. Demographic and clinical characteristics (eg, pectus severity and the number of bars used) of the patients will be recorded. All data will be collected by investigators who are blinded to the treatment. ETHICS AND DISSEMINATION: Ethical approval was obtained from the Ethics Committee on Biomedical Research of the West China Hospital of Sichuan University (2021-1275). During the period of the study, all procedures will be conducted following the principles of the Declaration of Helsinki. The results of the trial will be published in a peer-reviewed scientific journal. TRIAL REGISTRATION NUMBER: ChiCTR2200056596.

Safety and feasibility of ultrasound-guided serratus anterior plane block and intercostal nerve block for management of post-sternotomy pain in pediatric cardiac patients: A prospective, randomized trial.

BACKGROUND: Postoperative analgesia in the cardiothoracic ICU has traditionally relied on intravenous opioids. Thoracic nerve blocks are attractive alternatives for analgesia that reduce the requirement for opioids, but their safety and feasibility remain unclear. METHODS: Sixty children were allocated randomly to three groups: group C received intravenous opioids alone, while group SAPB (deep serratus anterior plane block) and group ICNB (intercostal nerve block) received opioids combined with ultrasound-guided regional nerve blocks (0.2% ropivacaine 2.5 mg.kg-1) after patients were transferred to the ICU. The primary outcome was opioid requirement in the first 24 h after surgery. Other outcomes included the postoperative FLACC scale value, tracheal extubation time, and plasma ropivacaine concentrations after the block. RESULTS: The mean [sd] cumulative dose of opioids administered postoperatively within 24 h in the SAPB (168.6 [76.9] µg.kg-1) and ICNB groups (170.0 [86.8] µg.kg-1) were significantly lower by nearly 53% than those in group C (359.3 [125.3] µg.kg-1, p = 0.000). The tracheal extubation time was shorter in the regional block groups than that in the control group, but the difference was not statistically significant (p = 0.177). The FLACC scale values at 0, 1, 3, 6, 12, and 24 h post-extubation were similar in the three groups. The mean peak plasma ropivacaine concentrations in the SAP and ICNB groups were 2.1 [0.8] and 1.8 [0.7] mg.L-1, respectively, 10 min post-block and then slowly decreased. No noticeable complications associated with regional anesthesia were observed. CONCLUSIONS: Ultrasound-guided SAPB and ICNB provided safe and satisfactory early postoperative analgesia while reducing opioid consumption following sternotomy in pediatric patients. CLINICAL TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiChiCTR2100046754.

Comparison of S-ketamine and midazolam for intravenous preoperative sedative and anxiolytic effects in preschool children: study protocol for a randomized controlled clinical trial.

BACKGROUND: Preoperative anxiety management is gaining particular attention in paediatric anaesthesia. Pharmacological and non-pharmacological resorts can be implemented to address this special issue. Despite the various approaches currently used for preoperative sedation in children, the different sedative and anti-anxiety effects between the newly marketed anaesthetic, S-ketamine, and the traditional sedative, midazolam, are still unclear. METHODS: This is a patient- and assessor-blinded randomized controlled clinical trial. Participants (n = 110) will receive S-ketamine (0.5 mg/kg) or midazolam (0.08 mg/kg) intravenously administrated at a ratio of 1:1 in the anaesthesia holding area. The primary outcome of this study is the sedative effect evaluated via the change in the modified Yale preoperative anxiety scale. It will be performed at two timepoints: in the pre-anaesthetic holding area before premedication (baseline, marked as T0) and about 5 min after premedication in the operating room without the existence of their guardians (marked as T1). Our secondary objectives include the parent separation anxiety score, postoperative agitation, caregivers' and anaesthesia care providers' satisfaction, and mask compliance. DISCUSSION: This randomized controlled trial is the first study to compare the anti-anxiety effect of intravenous S-ketamine and midazolam. We will provide a new approach for the clinical management of preoperative anxiety in preschool children posted for elective surgery. TRIAL REGISTRATION: ChiCTR2300069998. Registered on 30 March 2023.

Causal associations of iron status and back pain risk: A Mendelian randomization study.

Background: Observational studies have previously suggested a link between iron status makers and back pain. We conducted a two-sample Mendelian randomization (MR) study to determine the putative causal relationship between systemic iron status and back pain. Materials and methods: In this MR study, a genome-wide association study (GWAS) involving 48,972 individuals was used to identify genetic instruments highly associated with systemic iron status. The outcome data (back pain) were derived from the Neale Lab consortium's summary data from the UK Biobank (85,221 cases and 336,650 controls). With the inverse variance weighted (IVW) method as the main analysis, conservative analyses (selecting SNPs with concordant change of iron status biomarkers) and liberal analyses (selecting SNPs with genome-wide significant association with each iron status biomarker) were carried out. For sensitivity analyses, the MR-Egger, MR-Egger intercept, weighted median, weighted mode, and MR based on a Bayesian model averaging approaches were used. The Cochran's Q-test was used to detect heterogeneity. Results: Back pain was associated with genetically instrumented serum iron (OR = 1.01; 95% CI = 1.00-1.02, p = 0.01), ferritin (OR = 1.02; 95% CI = 1.00-1.04, p = 0.02), and transferrin saturation (OR = 1.01; 95% CI = 1.00-1.01, p = 0.01). Furthermore, there was no evidence of a link between transferrin and the risk of back pain (OR = 0.99, 95% CI = 0.98-1.00, p = 0.08). The sensitivity analyses and Cochran's Q-test indicated that no pleiotropy or heterogeneity was detected (all p > 0.05). Conclusion: We provided potential genetic evidences for the causal associations of iron status with increased incidence of back pain. However, the evidences were weakened due to the low power. Further larger MR studies or RCTs are needed to investigate small effects.

Proteomic analysis of Penicillin G acylases and resulting residues in semi-synthetic ß-lactam antibiotics using liquid chromatography - tandem mass spectrometry.

Penicillin G acylase (PGA), as a key enzyme, is increasingly used in the commercial production of semi-synthetic ß-lactam antibiotics (SSBAs). With the substitution of conventional chemical synthesis by emerging bioconversion processes, more and more PGAs fermented from different types of strains such as Escherichia coli (E. coli, ATCC 11105), Achromobacter sp. CCM 4824 and Providencia rettgeri (ATCC 31052) have been used in this kind of enzymatic processes. As an intermediate reaction catalyst, PGA protein and its presence in the final products may cause a potential risk of human allergic reaction and bring challenges for both quality and process controls. To achieve qualitative and quantitative analysis of PGAs and their residues in SSBAs, a tryptic digestion coupled with liquid chromatography - tandem mass spectrometry (LC-MS/MS) method was developed and proposed because of advantages like high selectivity and sensitivity. A suitable filter aided sample preparation (FASP) method was also used to remove matrix interference and to enrich the target PGA retained in the ultrafiltration membrane for an efficient enzymatic hydrolysis and subsequent accurate MS detection. Finally, twelve batches of PGAs from eight companies were identified and categorized into two types of strains (E. coli and Achromobacter sp. CCM 4824) using proteomic analysis. In total nine batches of five types of SSBAs (amoxicillin, cephalexin, cefprozil, cefdinir and cefaclor) from eight manufacturers were selected for investigation. Trace levels of PGA residual proteins ranging from 0.01 to 0.44 ppm were detected in six batches of different SSBAs which were far lower than the safety limit of 35 ppm reported by DSM, a manufacturer with expertise in the production of SSBAs by enzymatic processes. The developed FASP with LC-MS/MS method is superior to traditional protein assays in terms of selectivity, sensitivity and accuracy. Moreover, it could provide in-depth analysis of amino acid sequences and signature peptides contributing to assignment of the strain sources of PGAs. This method could become a promising and powerful tool to monitor enzymatic process robustness and reliability of this kind of SSBAs manufacturing.