Kinetics of PCDD/Fs from feed to cow milk and its implications for food safety.

Guideline levels of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) in feed and food have been separately recommended for the official food safety control around the world. However, less is considered about the transfer effect of PCDD/Fs from feed to food, and consequently possible human exposure risk. In this study, different controlled feeding experiments (E1 group: 4.92 pg TEQ/g in feed, E2 group: 0.61 pg TEQ/g in feed) were conducted on dairy cow (Chinese Holstein breed) to evaluate kinetics of PCDD/Fs from feed to milk and blood. Even though the PCDD/F level in feed in E2 was satisfied with the EU Regulation (No 277/2012), the TEQ levels in milk and tissues exceeded the European Union maximum level (EU ML) after approximately one-week exposure. The dynamic variation in milk during the initial 20-day exposure was successfully described by a first-order kinetic model. The levels at the plateau period showed a significant linear relationship (p < 0.01, R2 = 0.98) against the intake amounts from feed. Based on modeling, a maximum content was obtained at approximately 0.33 pg TEQ/g in cow feed with 12 % moisture to ensure the milk and meat safety under the current regulatory requirements of EU for cow-origin food. After the cease of exposure, the PCDD/F levels in milk declined below the EU ML within 40 days, while those in meat were still higher than the EU ML over 160 days. In serum, PCDD/Fs detected in E1 showed a similar dynamic variation during the exposure period. Regarding congener profile, higher-chlorinated congeners tended to transfer from feed to feces, whereas lower ones were preferably transferred into milk, which required specific concern about the metabolic effect of PCDD/Fs in large mammals. This study revealed a necessity for re-evaluation of official regulation on pollutants in cow feed and cow-origin food in terms of biotransfer and bioaccumulation.

Nitrogen mineralization in grazed BSC subsoil is mediated by itself and vegetation in the Loess Plateau, China.

Biological soil crust (BSC) exists widely in many kinds of grassland, its effect on soil mineralization in grazing systems has well been studied, but the impacts and threshold of grazing intensity on BSC have rarely been reported. This study focused on the dynamics of nitrogen mineralization rate in biocrust subsoils affected by grazing intensity. We studied the changes in BSC subsoil physicochemical properties and nitrogen mineralization rates under four sheep grazing intensities (i.e., 0, 2.67, 5.33, and 8.67 sheep ha-1) in seasons of spring (May-early July), summer (July-early September), and autumn (September-November). Although this moderate grazing intensity contributes to the growth and recovery of BSCs, we found that moss was more vulnerable to trampling than lichen, which means the physicochemical properties of the moss subsoil are more intense. Changes in soil physicochemical properties and nitrogen mineralization rates were significantly higher under 2.67-5.33 sheep ha-1 than other grazing intensities (Saturation phase). In addition, the structural equation model (SEM) showed that the main response path was grazing, which affected subsoil physicochemical properties through the joint mediation of BSC (25%) and vegetation (14%). Then, the further positive effect on nitrogen mineralization rate and the influence of seasonal fluctuations on the system was fully considered. We found that solar radiation and precipitation all had significant promoting effects on soil nitrogen mineralization rates, the overall seasonal fluctuation has a direct effect of 18% on the rate of nitrogen mineralization. This study revealed the effects of grazing on BSC and the results may enable a better statistical quantification of BSC functions and provide a theoretical basis to formulate grazing strategies in the grazing system of sheep in Loess Plateau even worldwide (BSC symbiosis).

The contradictory roles of tightly bound and loosely bound extracellular polymeric substances of activated sludge in trimethoprim adsorption process.

Extracellular polymeric substances (EPS) of activated sludge are a mixture of high molecular weight polymers secreted by microorganisms, which have the double structure of tightly-bound EPS (TB-EPS) in inner layer and loosely-bound EPS (LB-EPS) in outer layer. The characteristic of LB- and TB-EPS were different, which would affect their adsorption of antibiotics. However, the adsorption process of antibiotics on LB- and TB-EPS was still unclear yet. Therefore, in this work, the roles of LB-EPS and TB-EPS in adsorption of a typical antibiotic-trimethoprim (TMP) at environmentally relevant concentration (25.0 µg/L) were investigated. The results showed the content of TB-EPS was higher than that of LB-EPS, which was 17.08 and 10.36 mg/g VSS, respectively. The adsorption capacity of raw, LB-EPS extracted and both LB- and TB-EPS extracted activated sludges for TMP were 5.31, 4.65 and 9.51 µg/g VSS, respectively, which indicated LB-EPS had positive effect on TMP removal, while TB-EPS had negative effect. The adsorption process can be well described by a pseudo-second-order kinetic model (R2 > 0.980). The ratio of different functional groups was calculated and the CO and C-O bond might be responsible for the adsorption capacity difference between LB- and TB-EPS. The fluorescence quenching results indicated that tryptophan protein-like substances in LB-EPS provided more binding sites (n = 0.36) than that of tryptophan amino acid in TB-EPS (n = 0.1). Furthermore, the extend DLVO results also demonstrated that LB-EPS promoted the adsorption of TMP, while TB-EPS inhibited the process. We hope the results of this study were helpful for understanding the fate of antibiotics in wastewater treatment systems.

Predictors for the clinical prognosis of sylvian arachnoid cysts in children.

Objectives: To investigate the potential factors affecting the clinical prognosis of intracranial sylvian arachnoid cysts(IAC) in children. Methods: All patients with IAC admitted to our department from January, 1, 2015 to December, 31, 2016, were retrospectively reviewed. Patients were grouped based on surgical treatment (surgery cohort vs non-surgery cohort). The clinical and image outcome of the patients were followed routinely. The clinical characteristics and the prognosis of the patients were compared in different cohorts. Binary logistic regression analysis was applied to analyze the potential factors which may post an influence on the prognosis of the patients. Results: Of 500 patients admitted to our department for IAC, 424 patients had good prognosis and 76 had poor prognosis, with no deaths occurred during the follow-ups. 68 patients had IAC related complications and 91 patients developed new symptoms during the follow-ups. There were significant differences (P < 0.05) between the 2 cohorts in below aspects: age, gender, Galassi subtype, whether the mother was a unipara, the maximum diameter of the cysts at the first visit and the last follow-up, headache, head circumference, temporal bulge, new symptoms, cysts rupture and hemorrhage, subdural effusion, and IAC disappearance. The mean changes in the maximum diameter of the IAC for the patients were marginally higher for the surgery cohort than for the non-surgery cohort (P < 0.01). Binary logistic regression analysis suggested that the number of symptom, no new symptoms during follow-up, surgical treatment, age, maximum diameter of cysts at first diagnosis were independent risk factors affecting the prognosis of patients (P < 0.05). Conclusions: Patients older than 22.5 months, with the maximum diameter of IAC greater than 5.75 cm, who have multiple symptoms, born prematurely, develope new symptoms during the follow-ups and obvious symptoms after trauma need to conduct necessary surgical treatment in time. Patients with complications such as cysts rupture with hemorrhage and subdural effusion will acquire good prognosis after timely surgical treatment. IAC complete disappearance warrants no such important attention for the good prognosis.

Development of an efficient method for separation and purification of cordycepin from liquid fermentation of Cordyceps militaris and analysis of cordycepin antitumor activity.

Cordycepin (3 '-deoxyadenosine) is the main active component of Cordyceps militaris, which is a chemical marker for quality detection of Cordyceps militaris and has important medicinal development value. Existing methods for obtaining cordycepin are complex and costly. In this study, an economical and simple method for separation and purification of cordycepin from Cordyceps militaris fermentation liquid through physical crystallization was explored. First, lyophilized powdered fermentation liquid (LPFL) and pure methanol (1 g/100 mL, w/v) were mixed, and then repeatedly dissolved and crystallized until the precipitation was white. Purified product was obtained by freeze-drying the precipitate. The substance was determined to be cordycepin by high performance liquid chromatography, mass spectrometry and infrared spectroscopy, and the purity was 94.26%. Compared with the existing methods, this method is simple and low cost. In addition, the functional activity of cordycepin was determined by in vitro test. The results exhibited that cordycepin caused death and morphological changes in human colon cancer Caco-2 cells, and significantly inhibited the proliferation of Caco-2 cells, with a half-maximal inhibitory concentration (IC50) of 107.2 µg/mL. Cordycepin could induce early apoptosis of Caco-2 and caused cell cycle arrest in the G2 phase. Caco-2 cell apoptosis and cell cycle arrest showed dose dependence to cordycepin over a certain range. These results improved cordycepin purification method, provided insights into the mechanism of cordycepin in cancer inhibition, and would provide important reference for further development and clinical application of cordycepin.

Pre-stimulus gamma power in human posteromedial cortex shows supra-modal mechanisms in predicting the amplitude and latency of task-induced suppression.

Upon repetitively performing the same well-practiced task on identical bottom-up stimuli, our performance still varies. Although it has been well documented that elevated pre-stimulus baseline activity in the human default-mode network impairs the subsequent task performance, it remains unknown (i) the fine-grained temporal dynamics and (ii) whether the underlying neural dynamics are supra-modal or modality-specific. We utilized intracranial recordings in the human posteromedial cortex (PMC) during a simple visual and an auditory detection task. Our findings suggested that the pre-stimulus gamma power in PMC predicted the subsequent task performance. Critically, the higher the pre-stimulus gamma power, the longer it took for it to be suppressed, and the less suppressed it was during the task performance, which eventually resulted in deleterious effects on task performance, i.e. longer reaction times. These fine-grained temporal dynamics were consistent between the visual and auditory simple detection task. In addition, a direct comparison between the visual and auditory modality showed that the between-modality difference emerged during the recovery period from the maximal gamma suppression back to the baseline. Taken together, the present results contribute novel spatio-temporal mechanisms in human PMC on how simple detection performance varies across multiple repetitions, irrespective of the sensory modality involved.

Fluorescent Carbon Dots Derived From Soy Sauce for Picric Acid Detection and Cell Imaging.

Picric acid (PA) is a powerful nitro-aromatic explosive that harms the environment and human health. Developing non-toxic and low-cost sensors for the rapid detection of PA is essential. An environment-friendly fluorescent probe for PA detection is designed based on carbon dots (CDs) directly separated from edible soy sauce by silica gel column chromatography. Neither organic reagents nor heating process was needed to prepare CDs. The obtained CDs exhibit bright blue fluorescence, good water solubility, and photostability. The fluorescent probe for PA was developed according to the CD's fluorescence can be significantly quenched via the inner filter effect between CDs and PA. The linear range was 0.2-24 µM with a limit of detection of 70 nM. This proposed method was successfully employed to detect PA in the real water samples with satisfactory recoveries between 98.0-104.0%. Moreover, the CDs were suitable for fluorescence imaging of HeLa cells owing to their low toxicity and good biocompatibility.

Multivariable prediction models for atrial fibrillation after cardiac surgery: a systematic review protocol.

INTRODUCTION: Dozens of multivariable prediction models for atrial fibrillation after cardiac surgery (AFACS) have been published, but none have been incorporated into regular clinical practice. One of the reasons for this lack of adoption is poor model performance due to methodological weaknesses in model development. In addition, there has been little external validation of these existing models to evaluate their reproducibility and transportability. The aim of this systematic review is to critically appraise the methodology and risk of bias of papers presenting the development and/or validation of models for AFACS. METHODS: We will identify studies that present the development and/or validation of a multivariable prediction model for AFACS through searches of PubMed, Embase and Web of Science from inception to 31 December 2021. Pairs of reviewers will independently extract model performance measures, assess methodological quality and assess risk of bias of included studies using extraction forms adapted from a combination of the Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies checklist and the Prediction Model Risk of Bias Assessment Tool. Extracted information will be reported by narrative synthesis and descriptive statistics. ETHICS AND DISSEMINATION: This systemic review will only include published aggregate data, so no protected health information will be used. Study findings will be disseminated through peer-reviewed publications and scientific conference presentations. Further, this review will identify weaknesses in past AFACS prediction model development and validation methodology so that subsequent studies can improve upon prior practices and produce a clinically useful risk estimation tool. PROSPERO REGISTRATION NUMBER: CRD42019127329.

Hypoglycemic oligostilbenes from the stems of Caragana sinica.

Six new oligostilbenes, carastilphenols A-E (1-5) and (-)-hopeachinol B (6), with three reported oligostilbenes were obtained from the stems of Caragana sinica. The structures of compounds 1-6 were determined by comprehensive spectroscopy analysis, and their absolute configurations were determined by electronic circular dichroism calculations. Thus, natural tetrastilbenes were determined as absolute configuration for the first time. Also, we did several pharmacological essays. In the antiviral tests, compounds 2, 4 and 6 showed moderate anti-coxsackie virus B3 type (CVB3) effect on Vero cells activities in vitro with IC50 values of 19.2 âˆ¼ 69.3 µM; and compounds 3 and 4 showed different levels of anti-respiratory syncytial virus (RSV) effect on Hep2 cells activities in vitro with IC50 values of 23.1 and 33.3 µM, respectively. As for hypoglycemic activity, compounds 6-9 (10 µM) showed the inhibition of α-glucosidase in vitro with IC50 values of 0.1 âˆ¼ 0.4 µM; and compound 7 showed significant inhibition (88.8%, 10 µM) of protein tyrosine phosphatase 1B (PTP1B) with IC50 value of 1.1 µM in vitro.

PBL teaching design of medical genetics with the case of brachydactyly type A2.

Medical genetics, which is a frontier subject in biomedicine, is the clinical core of gene diagnosis and gene therapy. In the training of medical students, medical genetics plays an important role in bridging basic medicine and clinical medicine. In recent years, problem-based learning (PBL) has been widely used in medical education as an important method to cultivate the autonomous learning ability of medical students. In the current study, we designed and shared the research on brachydactyly type A2 (BDA2) as the main case of PBL teaching, in order to guide the students towards autonomous learning, and to cultivate independent analysis and problem solving ability instead of simple knowledge acquisition. Such excellent academic teaching will provide more high quality medical talents and internationally competitiveness for constructing a healthy China.

Overinterpretation of findings in machine learning prediction model studies in oncology: a systematic review.

BACKGROUND: In biomedical research, spin is the overinterpretation of findings, and it is a growing concern. To date, the presence of spin has not been evaluated in prognostic model research in oncology, including studies developing and validating models for individualised risk prediction. STUDY DESIGN AND SETTING: We conducted a systematic review, searching MEDLINE and EMBASE for oncology-related studies that developed and validated a prognostic model using machine learning published between 01/01/2019 and 05/09/2019. We used existing spin frameworks and described areas of highly suggestive spin practices. RESULTS: We included 62 publications (including 152 developed models; 37 validated models). Reporting was inconsistent between methods and the results in 27% of studies due to additional analysis and selective reporting. Thirty-two studies (out of 36 applicable studies) reported comparisons between developed models in their discussion and predominantly used discrimination measures to support their claims (78%). Thirty-five studies (56%) used an overly strong or leading word in their title, abstract, results, discussion or conclusion. CONCLUSION: The potential for spin needs to be considered when reading, interpreting, and using studies that developed and validated prognostic models in oncology. Researchers should carefully report their prognostic model research using words that reflect their actual results and strength of evidence.

Transport and natural attenuation of benzene vapor from a point source in the vadose zone.

The vadose zone is a very dynamic and active environment that directly affects natural attenuation and vapor intrusion of volatile organic compounds (VOCs). Therefore, it is important to understand the fate and transport of VOCs in the vadose zone. A column experiment combined with model study was conducted to investigate the influence of soil type, vadose zone thickness, and soil moisture content on benzene vapor transport and natural attenuation in the vadose zone. Vapor-phase biodegradation and volatilization to atmosphere for benzene are two main natural attenuation mechanism in the vadose zone. Our data showed that biodegradation in black soil is the main natural attenuation mechanism (82.8%) while volatilization is the main natural attenuation mechanism in quartz sand, floodplain soil, lateritic red earth and yellow earth (>71.9%). The R-UNSAT model-predicted soil gas concentration profile and flux were close with four soil column data except for yellow earth. Increasing the vadose zone thickness and soil moisture content significantly reduced the volatilization contribution while increased biodegradation contribution. The volatilization loss decreased from 89.3% to 45.8% when the vadose zone thickness increased from 30 cm to 150 cm. The volatilization loss decreased from 71.9% to 10.1% when the soil moisture content increased from 6.4% to 25.4%. Overall, this study provided valuable insights into clarifying the roles of soil type, moisture, and other environmental conditions in vadose zone natural attenuation mechanism and vapor concentration.

Air pollution control or economic development? Empirical evidence from enterprises with production restrictions.

Production restriction is an environmental regulation adopted in China to curb the air pollution of industrial enterprises. Frequent production restrictions may cause economic losses for enterprises and further hinder their green transformation. Polluting enterprises are faced with the dilemma of choosing environmental protection or economic development. Using panel data on industrial enterprises in China from 2016 to 2019, this paper evaluates the impact of production restrictions on both enterprises' environmental and economic performance with regression models. The results show that production restrictions significantly drop the concentrations of SO2 and NOx emitted from polluting enterprises. Meanwhile, production restrictions have significant negative effects on operating income, financial expenses, net profit, and environmental protection investment. The mechanism analysis reveals that production restrictions mitigate air pollutant concentrations by increasing the number of green patents and improving total factor productivity, which also verifies the Porter hypothesis. However, there is a masking mediating effect of environmental investment, which indicates that the reduction of environmental investment hinders the enterprise's efforts to control air pollution. In addition, heterogeneous analysis shows that the economic shock on microenterprises is larger than that on small enterprises. Implementing production restrictions for microenterprises may be a way to eliminate their backwards production capacity.

Characterization of the volatile profile and its estrogenic activity in Kadsura coccinea fruit.

ETHNOPHARMACOLOGICAL RELEVANCE: The fruit of Kadsura coccinea (Lem.) A. C. Smith is an ethnomedicine used to treat abnormal menstruation, menopausal syndrome, and female infertility among the Dong Nationality in China. AIM OF THE STUDY: Our study aimed to identify the volatile oil profiles of the K. coccinea fruit and elucidate their estrogenic activity. MATERIALS AND METHODS: The peel volatile oil (PeO), pulp volatile oil (PuO), and seed volatile oil (SeO) of K. coccinea were extracted using hydrodistillation and qualitatively analyzed using gas chromatography-mass spectrometry (GC-MS). Estrogenic activity was evaluated in vitro using cell assay and in vivo using immature female rats. Serum 17ß-Estradiol (E2) and follicle-stimulating hormone (FSH) levels were detected using ELISA. RESULTS: In total, 46 PeO, 27 PuO, and 42 SeO components representing 89.96%, 90.19%, and 97% of the total composition, respectively, were identified. The compounds with the highest content in PeO, PuO, and SeO were ß-caryophyllene, γ-amorphene, and n-hexadecanoic acid, respectively. PeO induced proliferation of MCF-7 cells with an EC50 of 7.40 µg/mL. Subcutaneous administration of 10 mg/kg PeO significantly increased the weight of the uteri in immature female rats, with no effect on serum E2 and FSH levels. PeO acted as an agonist of ERα and ERß. PuO and SeO showed no estrogenic activity. CONCLUSION: The chemical compositions of PeO, PuO, and SeO of K. coccinea are different. PeO is the main effective fraction for estrogenic activities, providing a new source of phytoestrogen for the treatment of menopausal symptoms.

Extracellular vesicles derived from CD4+ T cells carry DGKK to promote sepsis-induced lung injury by regulating oxidative stress and inflammation.

BACKGROUND: Sepsis is an abnormal immune response after infection, wherein the lung is the most susceptible organ to fail, leading to acute lung injury. To overcome the limitations of current therapeutic strategies and develop more specific treatment, the inflammatory process, in which T cell-derived extracellular vesicles (EVs) play a central role, should be explored deeply. METHODS: Liquid chromatography-tandem mass spectrometry was performed for serum EV protein profiling. The serum diacylglycerol kinase kappa (DGKK) and endotoxin contents of patients with sepsis-induced lung injury were measured. Apoptosis, oxidative stress, and inflammation in A549 cells, bronchoalveolar lavage fluid, and lung tissues of mice were measured by flow cytometry, biochemical analysis, enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, and western blot. RESULTS: DGKK, the key regulator of the diacylglycerol (DAG)/protein kinase C (PKC) pathway, exhibited elevated expression in serum EVs of patients with sepsis-induced lung injury and showed strong correlation with sepsis severity and disease progression. DGKK was expressed in CD4+ T cells under regulation of the NF-κB pathway and delivered by EVs to target cells, including alveolar epithelial cells. EVs produced by CD4+ T lymphocytes exerted toxic effects on A549 cells to induce apoptotic cell death, oxidative cell damage, and inflammation. In mice with sepsis induced by cecal ligation and puncture, EVs derived from CD4+ T cells also promoted tissue damage, oxidative stress, and inflammation in the lungs. These toxic effects of T cell-derived EVs were attenuated by the inhibition of PKC and NOX4, the downstream effectors of DGKK and DAG. CONCLUSIONS: This approach established the mechanism that T-cell-derived EVs carrying DGKK triggered alveolar epithelial cell apoptosis, oxidative stress, inflammation, and tissue damage in sepsis-induced lung injury through the DAG/PKC/NOX4 pathway. Thus, T-cell-derived EVs and the elevated distribution of DGKK should be further investigated to develop therapeutic strategies for sepsis-induced lung injury.

Mapping the long-term delayed recall-based cortex-hippocampus network constrained by the structural and functional connectome: a case-control multimodal MRI study.

BACKGROUND: Connectome mapping may reveal new treatment targets for patients with neurological and psychiatric diseases. However, the long-term delayed recall based-network with structural and functional connectome is still largely unknown. Our objectives were to (1) identify the long-term delayed recall-based cortex-hippocampus network with structural and functional connectome and (2) investigate its relationships with various cognitive functions, age, and activities of daily living. METHODS: This case-control study enrolled 131 subjects (73 amnestic mild cognitive impairment [aMCI] patients and 58 age- and education-matched healthy controls [HCs]). All subjects completed a neuropsychological battery, activities of daily living assessment, and multimodal magnetic resonance imaging. Nodes of the cortical-hippocampal network related to long-term delayed recall were identified by probabilistic fiber tracking and functional connectivity (FC) analysis. Then, the main and interaction effects of the network on cognitive functions were assessed by a generalized linear model. Finally, the moderating effects of the network on the relationships between long-term delayed recall and clinical features were analyzed by multiple regression and Hayes' bootstrap method. All the effects of cortex-hippocampus network were analyzed at the connectivity and network levels. RESULTS: The result of a generalized linear model showed that the bilateral hippocampus, left dorsolateral superior frontal gyrus, right supplementary motor area, left lingual gyrus, left superior occipital gyrus, left superior parietal gyrus, left precuneus, and right temporal pole (superior temporal gyrus) are the left and right cortex-hippocampus network nodes related to long-term delayed recall (P < 0.05). Significant interaction effects were found between the Auditory Verbal Learning Test Part 5 (AVLT 5) scores and global properties of the left cortex-hippocampus network [hierarchy, clustering coefficient, characteristic path length, global efficiency, local efficiency, Sigma and synchronization (P < 0.05 Bonferroni corrected)]. Significant interaction effects were found between the general cognitive function/executive function/language and global properties of the left cortex-hippocampus network [Sigma and synchronization (P < 0.05 Bonferroni corrected)]. CONCLUSION: This study introduces a novel symptom-based network and describes relationships among cognitive functions, brain function, and age. The cortex-hippocampus network constrained by the structural and functional connectome is closely related to long-term delayed recall.

Weathering and degradation of polylactic acid masks in a simulated environment in the context of the COVID-19 pandemic and their effects on the growth of winter grazing ryegrass.

The COVID-19 pandemic has led to explosive growth in the production and consumption of disposable medical masks, which has caused new global environmental problems due to the improper disposal of these masks and lack of effective mask recycling methods. To reduce the environmental load caused by the inability of synthetic plastics to degrade, polylactic acid (PLA) masks, as a biodegradable environmentally friendly plastic, may become a solution. This study simulated the actual degradation process of new PLA masks in different environments by soaking them in various solutions for 4 weeks and explored the influence of the treated PLA fabric fibers on the growth of winter ryegrass. The results show that the weathering degradation of PLA fibers in water mainly occurs through the hydrolysis of ester bonds, and weathering leads to cheese-like and gully-like erosion on the surface of the PLA fiber fabric layer and finally to fiber fracture and the release of microplastics (MPs). The average number of MPs released within 4 weeks is 149.5 items/piece, the particle size is 20-500 µm (44%), and 63.57% of the MPs are transparent fibers. The outer, middle, and inner layers of weathered PLA masks tend to be hydrophilic and have lower mechanical strength. PLA fibers after different treatment methods affect the growth of winter ryegrass. PLA masks are undoubtedly a greener choice than ordinary commercial masks, but in order to confirm this, the entire degradation process, the final products, and the impact on the environment need to be further studied. In the future, masks may be developed to be made from more environmentally friendly biodegradable materials that can have good protecting effects and also solve the problem of end-of-life recycling. A SYNOPSIS: Simulation of the actual degradation process of PLA masks and exploration of the influence of mask degradation on the growth of winter ryegrass.

A Case of Anti-GAD 65 Autoimmune Encephalitis Associated with Focal Segmental Stiff-Person Syndrome.

Glutamic acid decarboxylase (GAD) antibody-related encephalitis is an autoimmune disease associated with intracellular neuronal antigens. We report on a rare case of GAD antibody-associated encephalitis complicated with focal segmental stiffness-person syndrome (SPS) in a middle-aged woman. The disease course lasted for >10 years, initially presenting with drug-resistant epilepsy, followed by stiffness of the right lower limb, and right upper limb involvement. The patient experienced anxiety and depression symptoms due to long-term illness. During hospitalization, serum and cerebrospinal fluid GAD antibodies were positive and no tumor was found. The symptoms were significantly relieved after corticosteroid therapy and intravenous immunoglobulin immunomodulation therapy. To the best of our knowledge, this case is the first to discuss the early recognition and treatment of chronic epilepsy and focal segmental SPS caused by anti-GAD antibody-related encephalitis.

Study of the molecular characteristics and homology of carbapenem-resistant Proteus mirabilis by whole genome sequencing.

Introduction. Proteus mirabilis is part of the family Enterobacteriaceae, and is naturally resistant to various antimicrobial drugs. In recent years, outbreaks of severe nosocomial infections caused by carbapenem-resistant P. mirabilis (CR-PMI) have been frequently reported. Few studies exist on the whole-genome molecular characteristics of this bacterium in China and elsewhere, which stimulated the implementation of this study.Hypothesis. CR-PMI strains contained the multiple drug resistance genes and exhibited a high resistance rate to commonly used antimicrobial drugs.Aim. Our goals here were to identify resistance mechanisms and homology of CR-PMI strains and provide a theoretical basis for clinical treatment and controlling nosocomial infections.Methodology. Bacterial species identification was carried out using matrix-assisted laser desorption/ionization time of flight MS (MALDI-TOF-MS). Antimicrobial susceptibility was determined using the VITEK 2 system and Kirby-Bauer (K-B) disc-diffusion method. Whole-genome sequencing (WGS) was conducted by the Illumina platform NovaSeq sequencer. Antibiotic resistance genes (ARGs) were identified using the NCBI database with Abricate. Plasmid replicon types were identified using PlasmidFinder, available at the Center for Genomic Epidemiology.Results. Five CR-PMI strains collected in our hospital from July 2019 to September 2021 were resistant to almost all antimicrobial agents except aztreonam (ATM), amikacin (AMK) and cefotetan (CTT). All CR-PMI strains contained the carbapenem resistance gene New Delhi metallo-ß-lactamase 1 (bla NDM-1), and two strains harboured extended-spectrum ß-lactamase (ESBL) genes bla PER-4 and bla CTX-M-65. The five CR-PMI strains contained 27, 18, 30, 25 and 24 drug-resistance genes, respectively. Most antimicrobial resistance genes were detected for aminoglycosides (n=14), followed by cephalosporins (n=7). The phylogenetic tree was divided into five evolutionary groups, and the five CR-PMI strains were in the four evolutionary groups B-E.Conclusion Overall, CR-PMI strains exhibited a high resistance rate to commonly used antimicrobial drugs, and contained the carbapenem resistance gene bla NDM-1. The CR-PMI strains showed a polyclonal trend in different wards at different times. Most importantly, all strains identified contained important antimicrobial resistance genes, which may lead to severe drug resistance transmission and fatal multiple resistant bacterial infections.

Polydopamine-coated 3D-printed ß-tricalcium phosphate scaffolds to promote the adhesion and osteogenesis of BMSCs for bone-defect repair: mRNA transcriptomic sequencing analysis.

Cellular bioactivity and tissue regeneration can be affected by coatings on tissue-engineered scaffolds. Using mussel-inspired polydopamine (PDA) is a convenient and effective approach to surface modification. Therefore, 3D-printed ß-tricalcium phosphate (ß-TCP) scaffolds were coated with PDA in this study. The effects of the scaffolds on the adhesion and osteogenic differentiation of seeded bone marrow mesenchymal stem cells (BMSCs) in vitro and on new-bone formation in vivo were investigated. The potential mechanisms and related differential genes were assessed using mRNA sequencing. It was seen that PDA coating increased the surface roughness of the 3D-printed ß-TCP scaffolds. Furthermore, it prompted the adhesion and osteogenic differentiation of seeded BMSCs. mRNA sequencing analysis revealed that PDA coating might affect the osteogenic differentiation of BMSCs through the calcium signaling pathway, Wnt signaling pathway, TGF-beta signaling pathway, etc. Moreover, the expression of osteogenesis-related genes, such as R-spondin 1 and chemokine c-c-motif ligand 2, was increased. Finally, both the 3D-printed ß-TCP scaffolds and PDA-coated scaffolds could significantly accelerate the formation of new bone in critical-size calvarial defects in rats compared with the control group; and the new bone formation was obviously higher in the PDA-coated scaffolds than in ß-TCP scaffolds. In summary, 3D-printed ß-TCP scaffolds with a PDA coating can improve the physicochemical characteristics and cellular bioactivity of the scaffold surface for bone regeneration. Potential differential genes were identified, which can be used as a foundation for further research.