Preclinical Evaluation of Azabenzimidazole-Based PET Radioligands for γ-8 Dependent Transmembrane AMPA Receptor Regulatory Protein Imaging

AMPA glutamate receptors (AMPARs) play a pivotal role in excitatory neurotransmission, particularly in the hippocampus where the TARP γ-8 subunit is enriched and serves as a target for emerging anti-epileptic drugs. To enable in vivo visualization of TARP γ-8 distribution and expression by positron emission tomography (PET), this study focuses on the development of novel 18 F-labeled TARP γ-8 inhibitors and their corresponding precursors, stemming from the azabenzimidazole scaffold. The resulting radioligands [18 F]TARP-2204 and [18 F]TARP-2205 were successfully synthesized with acceptable radiochemical yield, high molar activity, and excellent radiochemical purity. In vitro autoradiography demonstrates high level of specific binding of [18 F]TARP-2205 to TARP γ-8 in both rat and nonhuman primate brain tissues. However, unexpected radiodefluorination in PET imaging studies of rodents emphasizes the need for further structural refinement. This work serves as an excellent starting point for the development of future 18 F-labeled TARP γ-8 PET tracers, offering valuable insights into medicinal chemistry design, radiosynthesis and subsequent PET evaluation.

[Design of an improved percutaneous transhepatic cholangio drainage tube based on MRCP imaging data]

Objective: Quantified MRCP imaging data was used as a reference for design and preparation of a modified percutaneous transhepatic cholangio drainage (PTCD) tube. Methods: 3.0 T upper abdominal MR and MRCP imaging data of 2 300 patients treated from July 2015 to July 2020 at the Department of Radiology of the Affiliated Cancer Hospital of Zhengzhou University were screened and a total of 381 patients diagnosed with biliary duct structures were identified. Causative etiologies among these patients included pancreatic adenocarcinoma (pancreatic head), cholangiocarcinoma, ampullary carcinoma, as well as intrahepatic and/or extrahepatic bile duct dilation. An improved PTCD tube was designed based on MRCP quantification of left and right hepatic and common hepatic duct length. Results: In the setting of biliary obstruction caused by malignancy, the distance of the left hepatic duct from its origin to the point of left and right hepatic duct confluence was 15.9±3.8 mm, while the distance of the right hepatic duct from its origin to the point of left and right hepatic duct confluence was 12.4±3.2 mm; the length of the bile duct from its origin to the point of left and right hepatic duct confluence was 34.0±8.1 mm. The improved PTCD tube design incorporated an altered length of the drainage orifice. Conclusion: MRCP imaging of the biliary tract is effective for measuring biliary tract length in the setting of pathological dilation. Based on our biliary tract measurements, a modified PTCD tube was designed to more effectively meet drainage requirements and manage biliary obstruction caused by Bismuth-Corlette type Ⅱ and Ⅲ malignancies.

Association of serum lipids and abnormal lipid score with cancer risk: a population-based prospective study

BACKGROUND

Serum lipid levels are associated with cancer risk. However, there still have uncertainties about the single and combined effects of low lipid levels on cancer risk.

METHODS

A prospective cohort study of 33,773 adults in Shanghai between 2016 and 2017 was conducted. Total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) levels were measured. Cox proportional hazard models were used to assess the association of single and combined lipids with overall, lung, colon, rectal, thyroid gland, stomach, and female breast cancers. The effect of the combination of abnormal lipid score and lifestyle on cancer was also estimated.

RESULTS

A total of 926 incident cancer cases were identified. In the RCS analysis, hazard ratios (HRs) of overall cancer for individuals with TC < 5.18 mmol/L or with LDL-C < 3.40 mmol/L were higher. Low TC was associated with higher colorectal cancer risk (HR [95% CI] = 1.76 [1.09-2.84]) and low HDL-C increased thyroid cancer risk by 90%. Abnormal lipid score was linearly and positively associated with cancer risk, and smokers with high abnormal lipid scores had a higher cancer risk, compared to non-smokers with low abnormal lipid scores (P < 0.05).

CONCLUSIONS

Low TC levels were associated with an increased risk of overall and colorectal cancer. More attention should be paid to participants with high abnormal lipid scores and unhealthy lifestyles who may have a higher risk of developing cancer. Determining the specific and comprehensive lipid combinations that affect tumorigenesis remains a valuable challenge.

Clinical features, functional consequences, and rescue pharmacology of missense GRID1 and GRID2 human variants

GRID1 and GRID2 encode the enigmatic GluD1 and GluD2 proteins, which form tetrameric receptors that play important roles in synapse organization and development of the central nervous system. Variation in these genes has been implicated in neurodevelopmental phenotypes. We evaluated GRID1 and GRID2 human variants from the literature, ClinVar, and clinical laboratories and found that many of these variants reside in intolerant domains, including the amino terminal domain of both GRID1 and GRID2. Other conserved regions, such as the M3 transmembrane domain, show different intolerance between GRID1 and GRID2. We introduced these variants into GluD1 and GluD2 cDNA and performed electrophysiological and biochemical assays to investigate the mechanisms of dysfunction of GRID1/2 variants. One variant in the GRID1 distal amino terminal domain resides at a position predicted to interact with Cbln2/Cbln4, and the variant disrupts complex formation between GluD1 and Cbln2, which could perturb its role in synapse organization. We also discovered that, like the lurcher mutation (GluD2-A654T), other rare variants in the GRID2 M3 domain create constitutively active receptors that share similar pathogenic phenotypes. We also found that the SCHEMA schizophrenia M3 variant GluD1-A650T produced constitutively active receptors. We tested a variety of compounds for their ability to inhibit constitutive currents of GluD receptor variants and found that pentamidine potently inhibited GluD2-T649A constitutive channels (IC50 50 nM). These results identify regions of intolerance to variation in the GRID genes, illustrate the functional consequences of GRID1 and GRID2 variants, and suggest how these receptors function normally and in disease.

Interface Charge Distribution Engineering of Pd-CeO2 /C for Efficient Carbohydrazide Oxidation Reaction

Carbohydrazide electrooxidation reaction (COR) is a potential alternative to oxygen evolution reaction in water splitting process. However, the sluggish kinetics process impels to develop efficient catalysts with the aim of the widespread use of such catalytic system. Since COR concerns the adsorption/desorption of reactive species on catalysts, the electronic structure of electrocatalyst can affect the catalytic activity. Interface charge distribution engineering can be considered to be an efficient strategy for improving catalytic performance, which facilitates the cleavage of chemical bond. Herein, highly dispersed Pd nanoparticles on CeO2 /C catalyst are prepared and the COR catalytic performance is investigated. The self-driven charge transfer between Pd and CeO2 can form the local nucleophilic and electrophilic region, promoting to the adsorption of electron-withdrawing and electron-donating group in carbohydrazide molecule, which facilitates the cleavage of C-N bond and the carbohydrazide oxidation. Due to the local charge distribution, the Pd-CeO2 /C exhibits superior COR catalytic activity with a potential of 0.27 V to attain 10 mA cm-2 . When this catalyst is used for energy-efficient electrolytic hydrogen production, the carbohydrazide electrolysis configuration exhibits a low cell voltage (0.6 V at 10 mA cm-2 ). This interface charge distribution engineering can provide a novel strategy for improving COR catalytic activity.

Therapeutic potential of N-methyl-D-aspartate receptor modulators in psychiatry

N-methyl-D-aspartate (NMDA) receptors mediate a slow component of excitatory synaptic transmission, are widely distributed throughout the central nervous system, and regulate synaptic plasticity. NMDA receptor modulators have long been considered as potential treatments for psychiatric disorders including depression and schizophrenia, neurodevelopmental disorders such as Rett Syndrome, and neurodegenerative conditions such as Alzheimer's disease. New interest in NMDA receptors as therapeutic targets has been spurred by the findings that certain inhibitors of NMDA receptors produce surprisingly rapid and robust antidepressant activity by a novel mechanism, the induction of changes in the brain that well outlast the presence of drug in the body. These findings are driving research into an entirely new paradigm for using NMDA receptor antagonists in a host of related conditions. At the same time positive allosteric modulators of NMDA receptors are being pursued for enhancing synaptic function in diseases that feature NMDA receptor hypofunction. While there is great promise, developing the therapeutic potential of NMDA receptor modulators must also navigate the potential significant risks posed by the use of such agents. We review here the emerging pharmacology of agents that target different NMDA receptor subtypes, offering new avenues for capturing the therapeutic potential of targeting this important receptor class.

Role of LncMALAT1-miR-141-3p/200a-3p-NRXN1 Axis in the Impairment of Learning and Memory Capacity in ADHD

As a prevalent neurodevelopmental disease, attention-deficit hyperactivity disorder (ADHD) impairs the learning and memory capacity, and so far, there has been no available treatment option for long-term efficacy. Alterations in gene regulation and synapse-related proteins influence learning and memory capacity; nevertheless, the regulatory mechanism of synapse-related protein synthesis is still unclear in ADHD. LncRNAs have been found participating in regulating genes in multiple disorders. For instance, lncRNA Metastasis Associated Lung Adenocarcinoma Transcript 1 (MALAT1) has an essential regulatory function in numerous psychiatric diseases. However, how MALAT1 influences synapse-related protein synthesis in ADHD remains largely unknown. Here, our study found that MALAT1 decreased in the hippocampus tissue of spontaneously hypertensive rats (SHRs) compared to the standard controls, Wistar Kyoto (WKY) rats. Subsequent experiments revealed that MALAT1 enhanced the expression of neurexin 1 (NRXN1), which promoted the synapse-related genes (SYN1, PSD95, and GAP43) expression. Then, the bioinformatic analyses predicted that miR-141-3p and miR-200a-3p, microRNAs belonging to miR-200 family and sharing same seed sequence, could interact with MALAT1 and NRXN1 mRNA, which were further confirmed by luciferase report assays. Finally, rescue experiments indicated that MALAT1 influenced the expression of NRXN1 by sponging miR-141-3p/200a-3p. All data verified our hypothesis that MALAT1 regulated synapse-related proteins (SYN1, PSD95, and GAP43) through the MALAT1-miR-141-3p/200a-3p-NRXN1 axis in ADHD. Our research underscored a novel role of MALAT1 in the pathogenesis of impaired learning and memory capacity in ADHD and may shed more light on developing diagnostic biomarkers and more effective therapeutic interventions for individuals with ADHD.

Lumbar Spinal Stenosis and Minimally Invasive Lumbar Decompression: A Narrative Review

Background

Lumbar spinal stenosis (LSS) is a common pain condition that causes lumbar back pain, radiating leg pain, and possible functional impairment. MILD is an emerging minimally invasive treatment for LSS. It is an image-guided percutaneous procedure designed to debulk hypertrophied ligamentum flavum. However, the exact short- and long-term efficacy, safety profile, indication criteria, and certain procedure details reported in medical literature vary.

Objective

This narrative review was to elucidate efficacy, safety profile, certain procedure details, advantages, and limitations of MILD.

Study Design

This is a narrative review.

Setting

All included articles are clinic trials including analytic studies and descriptive studies.

Methods

PubMed, Cochrane Library, and Scopus were searched. Only clinical trials of MILD procedure were included. Information of indications, contraindications, VAS scores, ODI scores, effective rate, efficacy durations, and certain procedure details was focused on.

Results

According to the literature, for the MILD procedure, the VAS score could be reduced from a pre-treatment level of 6.3-9.6 to a post-treatment level of 2.3-5.8. The ODI score could be reduced from a pre-treatment level of 38.8-55.3 to a post-treatment level of 27.4-39.8. The effective rate of the MILD procedure was reported to be 57.1%-88%. A 2-year postoperative stability of efficacy was also supported. One RCT study testified superior efficacy of MILD over epidural steroid injection.

Limitations

There is few high-quality literature in the review. Moreover, the long-term efficacy of MILD cannot be revealed according to the current literature.

Conclusion

Based on the reviewed literature, MILD is an effective and safe procedure. MILD can reduce pain intensity and improve functional status significantly. Therefore, it is a preferable option for LSS patients who failed conservative treatments, but not for those who require immediate invasive decompression surgery.

Clinical and functional consequences of GRIA variants in patients with neurological diseases

AMPA receptors are members of the glutamate receptor family and mediate a fast component of excitatory synaptic transmission at virtually all central synapses. Thus, their functional characteristics are a critical determinant of brain function. We evaluate intolerance of each GRIA gene to genetic variation using 3DMTR and report here the functional consequences of 52 missense variants in GRIA1-4 identified in patients with various neurological disorders. These variants produce changes in agonist EC50, response time course, desensitization, and/or receptor surface expression. We predict that these functional and localization changes will have important consequences for circuit function, and therefore likely contribute to the patients' clinical phenotype. We evaluated the sensitivity of variant receptors to AMPAR-selective modulators including FDA-approved drugs to explore potential targeted therapeutic options.

Alive but not well: The neglected cost of air pollution

Besides medical expenses, hospitalizations associated with air pollution will incur the welfare loss due to activity restrictions and the wage loss due to inability to work. We fill in the gap in the literature by examining the impact of air pollution on volume and intensity of hospitalizations, which allows us to incorporate the welfare loss and the wage loss. Using a data set that covers most of the inpatients in a major Chinese city during 2015-16, we find that worse air quality causes more hospital admissions, more total inpatient days, and higher total inpatient expenditure for various diseases, particularly diseases of the respiratory and circulatory systems. We also find that there would be an underestimate of the loss from air pollution if we had ignored the loss associated with activity restrictions and the wage loss during hospitalization.

De novo CLPTM1 variants with reduced GABAA R current response in patients with epilepsy

OBJECTIVE

To investigate the clinical features and potential pathogenesis mechanism of de novo CLPTM1 variants associated with epilepsy.

METHODS

Identify de novo genetic variants associated with epilepsy by reanalyzing trio-based whole-exome sequencing data. We analyzed the clinical characteristics of patients with these variants and performed functional in vitro studies in cells expressing mutant complementary DNA for these variants using whole-cell voltage-clamp current recordings and outside-out patch-clamp recordings from transiently transfected human embryonic kidney (HEK) cells.

RESULTS

Two de novo missense variants related to epilepsy were identified in the CLPTM1 gene. Functional studies indicated that CLPTM1-p.R454H and CLPTM1-p.R568Q variants reduced the γ-aminobutyric acid A receptor (GABAA R) current response amplitude recorded under voltage clamp compared to the wild-type receptors. These variants also reduced the charge transfer and altered the time course of desensitization and deactivation following rapid removal of GABA. The surface expression of the GABAA R γ2 subunit from the CLPTM1-p.R568Q group was significantly reduced compared to CLPTM1-WT.

SIGNIFICANCE

This is the first report of functionally relevant variants within the CLPTM1 gene. Patch-clamp recordings showed that these de novo CLPTM1 variants reduce GABAA R currents and charge transfer, which should promote excitation and hypersynchronous activity. This study may provide insights into the molecular mechanisms of the CLPTM1 variants underlying the patients' phenotypes, as well as for exploring potential therapeutic targets for epilepsy.

[Risk factors and construction of a nomogram model for cirrhotic portal vein thrombosis combined with esophagogastric variceal bleeding]

Objective: To investigate the risk factors and construct a nomogram model for predicting the occurrence of cirrhotic portal vein thrombosis in patients combined with esophagogastric variceal bleeding (EVB). Methods: Clinical data on 416 cirrhotic PVT cases was collected from the First Hospital of Lanzhou University between January 2016 and January 2022. A total of 385 cases were included after excluding 31 cases for retrospective analysis. They were divided into an esophagogastric variceal bleeding group and a non-esophagogastric variceal bleeding group based on the clinical diagnosis. The esophagogastric variceal group was then further divided into an EVB group and a non-bleeding group. All patients underwent gastroscopy, serology, and imaging examinations. The risk factors of PVT combined with EVB were identified by univariate analysis using SPSS 26. The prediction model of cirrhotic PVT in patients combined with EVB was constructed by R 4.0.4. The prediction efficiency and clinical benefits of the model were evaluated by the C-index, area under the receiver operating characteristic curve, calibration plots, and decision curve. The measurement data were examined by a t-test or Mann-Whitney U test. The counting data were tested using the χ(2) test or the Fisher exact probability method. Results: There were statistically significant differences in the etiology, Child-Pugh grade,erythrocyte count, hematocrit, globulin, and serum lipids between the esophageal and non-esophageal varices groups (P < 0.05). There were statistically significant differences in etiology, erythrocyte count, hemoglobin, hematocrit, neutrophil percentage, total protein, globulin, albumin/globulin, urea, high-density lipoprotein cholesterol, calcium, and neutrophil lymphocyte ratio (NLR) between the EVB and non-bleeding groups (P < 0.05). Multivariate logistic regression analysis showed that etiology (OR = 3.287, 95% CI: 1.497 ~ 7.214), hematocrit (OR = 0.897, 95% CI: 0.853 ~ 0.943), and high-density lipoprotein cholesterol (OR = 0.229, 95% CI: 0.071 ~ 0.737) were independent risk factors for cirrhotic PVT patients combined with EVB. The constructed normogram model predicted the probability of bleeding in patients. The nomogram model had shown good consistency and differentiation (AUC = 0.820, 95% CI: 0.707 ~ 0.843), as verified by 10-fold cross-validation (C-index = 0.799) and the Hosmer-Lemeshow goodness of fit test (P = 0.915). The calibration plot and the decision curve suggested that the prediction model had good stability and clinical practicability. Conclusion: The risk factors for EVB occurrence include etiology, erythrocyte, hemoglobin, hematocrit, percentage of neutrophils, total protein, globulin, albumin/globulin, urea, high-density lipoprotein cholesterol, calcium, and NLR in patients with cirrhotic liver. The constructed prediction model has good predictive value, and it can provide a reference for medical personnel to screen patients with high bleeding risk for targeted treatment.

Loss of Grin2a causes a transient delay in the electrophysiological maturation of hippocampal parvalbumin interneurons

N-methyl-D-aspartate receptors (NMDARs) are ligand-gated ionotropic glutamate receptors that mediate a calcium-permeable component to fast excitatory neurotransmission. NMDARs are heterotetrameric assemblies of two obligate GluN1 subunits (GRIN1) and two GluN2 subunits (GRIN2A-GRIN2D). Sequencing data shows that 43% (297/679) of all currently known NMDAR disease-associated genetic variants are within the GRIN2A gene, which encodes the GluN2A subunit. Here, we show that unlike missense GRIN2A variants, individuals affected with disease-associated null GRIN2A variants demonstrate a transient period of seizure susceptibility that begins during infancy and diminishes near adolescence. We show increased circuit excitability and CA1 pyramidal cell output in juvenile mice of both Grin2a+/- and Grin2a-/- mice. These alterations in somatic spiking are not due to global upregulation of most Grin genes (including Grin2b). Deeper evaluation of the developing CA1 circuit led us to uncover age- and Grin2a gene dosing-dependent transient delays in the electrophysiological maturation programs of parvalbumin (PV) interneurons. We report that Grin2a+/+ mice reach PV cell electrophysiological maturation between the neonatal and juvenile neurodevelopmental timepoints, with Grin2a+/- mice not reaching PV cell electrophysiological maturation until preadolescence, and Grin2a-/- mice not reaching PV cell electrophysiological maturation until adulthood. Overall, these data may represent a molecular mechanism describing the transient nature of seizure susceptibility in disease-associated null GRIN2A patients.

Classification of missense variants in the N-methyl-d-aspartate receptor GRIN gene family as gain- or loss-of-function

Advances in sequencing technology have generated a large amount of genetic data from patients with neurological conditions. These data have provided diagnosis of many rare diseases, including a number of pathogenic de novo missense variants in GRIN genes encoding N-methyl-d-aspartate receptors (NMDARs). To understand the ramifications for neurons and brain circuits affected by rare patient variants, functional analysis of the variant receptor is necessary in model systems. For NMDARs, this functional analysis needs to assess multiple properties in order to understand how variants could impact receptor function in neurons. One can then use these data to determine whether the overall actions will increase or decrease NMDAR-mediated charge transfer. Here, we describe an analytical and comprehensive framework by which to categorize GRIN variants as either gain-of-function (GoF) or loss-of-function (LoF) and apply this approach to GRIN2B variants identified in patients and the general population. This framework draws on results from six different assays that assess the impact of the variant on NMDAR sensitivity to agonists and endogenous modulators, trafficking to the plasma membrane, response time course and channel open probability. We propose to integrate data from multiple in vitro assays to arrive at a variant classification, and suggest threshold levels that guide confidence. The data supporting GoF and LoF determination are essential to assessing pathogenicity and patient stratification for clinical trials as personalized pharmacological and genetic agents that can enhance or reduce receptor function are advanced. This approach to functional variant classification can generalize to other disorders associated with missense variants.

Development of a Dihydroquinoline-Pyrazoline GluN2C/2D-Selective Negative Allosteric Modulator of the N-Methyl-d-aspartate Receptor

Subunit-selective inhibition of N-methyl-d-aspartate receptors (NMDARs) is a promising therapeutic strategy for several neurological disorders, including epilepsy, Alzheimer's and Parkinson's disease, depression, and acute brain injury. We previously described the dihydroquinoline-pyrazoline (DQP) analogue 2a (DQP-26) as a potent NMDAR negative allosteric modulator with selectivity for GluN2C/D over GluN2A/B. However, moderate (<100-fold) subunit selectivity, inadequate cell-membrane permeability, and poor brain penetration complicated the use of 2a as an in vivo probe. In an effort to improve selectivity and the pharmacokinetic profile of the series, we performed additional structure-activity relationship studies of the succinate side chain and investigated the use of prodrugs to mask the pendant carboxylic acid. These efforts led to discovery of the analogue (S)-(-)-2i, also referred to as (S)-(-)-DQP-997-74, which exhibits >100- and >300-fold selectivity for GluN2C- and GluN2D-containing NMDARs (IC50 0.069 and 0.035 μM, respectively) compared to GluN2A- and GluN2B-containing receptors (IC50 5.2 and 16 μM, respectively) and has no effects on AMPA, kainate, or GluN1/GluN3 receptors. Compound (S)-(-)-2i is 5-fold more potent than (S)-2a. In addition, compound 2i shows a time-dependent enhancement of inhibitory actions at GluN2C- and GluN2D-containing NMDARs in the presence of the agonist glutamate, which could attenuate hypersynchronous activity driven by high-frequency excitatory synaptic transmission. Consistent with this finding, compound 2i significantly reduced the number of epileptic events in a murine model of tuberous sclerosis complex (TSC)-induced epilepsy that is associated with upregulation of the GluN2C subunit. Thus, 2i represents a robust tool for the GluN2C/D target validation. Esterification of the succinate carboxylate improved brain penetration, suggesting a strategy for therapeutic development of this series for NMDAR-associated neurological conditions.

How does adoption of electric vehicles reduce carbon emissions? Evidence from China

We investigate the effect of the adoption of electric vehicles (EVs) on CO2 emissions using spatial econometric models and have three findings. First, there are spatial spillover effects of EV adoption on CO2 emissions, implying that the CO2 mitigation of a city depends on local sales of EVs and sales of EVs in neighboring cities. A 1% increase in the sale of EVs in a city can reduce CO2 emissions locally by 0.096% and by 0.087% in a nearby city. Second, EVs indirectly impact CO2 emissions through the substitution effect, energy consumption effect, and technological effect. The overall impact of EV adoption on CO2 emissions is negative. Finally, we demonstrate the moderating effect of urban energy structure on EVs' CO2 emissions mitigation. A 1% increase in the proportion of renewable energy generation increases the decarbonization of EVs by 0.036%. These findings provide policy implications for the coordinated development of EV market and energy system.

Differential responses of disease-related GRIN variants located in pore-forming M2 domain of N-methyl-D-aspartate receptor to FDA-approved inhibitors

N-methyl-D-aspartate receptors (NMDAR), ionotropic glutamate receptors, mediate a slow component of excitatory synaptic transmission in the central nervous system and play a key role in normal brain function and development. Genetic variations in GRIN genes encoding NMDAR subunits that alter the receptor's functional characteristics are associated with a wide range of neurological and neuropsychiatric conditions. Pathological GRIN variants located in the M2 re-entrant loop lining the channel pore cause significant functional changes, the most consequential alteration being a reduction in voltage-dependent Mg2+ inhibition. Voltage-dependent Mg2+ block is a unique feature of NMDAR biology whereby channel activation requires both ligand binding and postsynaptic membrane depolarization. Thus, loss of NMDAR Mg2+ block will have a profound impact on synaptic function and plasticity. Here, we choose 11 missense variants within the GRIN1, GRIN2A, and GRIN2B genes that alter residues located in the M2 loop and significantly reduce Mg2+ inhibition. Each variant was evaluated for tolerance to genetic variation using the 3-dimensional structure and assessed for functional rescue pharmacology via electrophysiological recordings. Three FDA-approved NMDAR drugs-memantine, dextromethorphan, and ketamine-were chosen based on their ability to bind near the M2 re-entrant loop, potentially rectifying dysregulated NMDAR function by supplementing the reduced voltage-dependent Mg2+ block. These results provide insight of structural determinants of FDA-approved NMDAR drugs at their binding sites in the channel pore and may further define conditions necessary for the use of such agents as potential rescue pharmacology.

Compulsory schooling system and equity in education: An analysis on intergenerational transmission of education

This paper uses the China Family Panel Studies' micro-level data and the ordered logit model to study intergenerational transmission of education and examines whether the nine-year compulsory schooling system affects equity in education. The results show that when parents have higher educational attainments, their children will have higher educational attainments. Full-sample results show that when the mother has higher education, the probability that her children have higher education increases by 7.97%, whereas for the sub-sample after the compulsory schooling policy carried out, the probability increases by 22.42%. We find that the compulsory schooling system strengthens intergenerational transmission of education in the level of higher education. An implication is that the compulsory schooling system may promote equity in compulsory education but does not promote equity in higher education.

[Revision rate of periprosthetic joint infection post total hip or knee arthroplasty of 34 hospitals in China between 2015 and 2017: a multi-center survey]

Objective: To investigate the rate of periprosthetic joint infection (PJI) revision surgeries and clinical information of hip-/knee- PJI cases nationwide from 2015 to 2017 in China. Methods: An epidemiological investigation. A self-designed questionnaire and convenience sampling were used to survey 41 regional joint replacement centers nationwide from November 2018 to December 2019 in China. The PJI was diagnosed according to the Musculoskeletal Infection Association criteria. Data of PJI patients were obtained by searching the inpatient database of each hospital. Questionnaire entries were extracted from the clinical records by specialist. Then the differences in rate of PJI revision surgery between hip- and knee- PJI revision cases were calculated and compared. Results: Total of 36 hospitals (87.8%) nationwide reported data on 99 791 hip and knee arthroplasties performed from 2015 to 2017, with 946 revisions due to PJI (0.96%). The overall hip-PJI revision rate was 0.99% (481/48 574), and it was 0.97% (135/13 963), 0.97% (153/15 730) and 1.07% (193/17 881) in of 2015, 2016, 2017, respectively. The overall knee-PJI revision rate was 0.91% (465/51 271), and it was 0.90% (131/14 650), 0.88% (155/17 693) and 0.94% (179/18 982) in 2015, 2016, 2017, respectively. Heilongjiang (2.2%, 40/1 805), Fujian (2.2%, 45/2 017), Jiangsu (2.1%, 85/3 899), Gansu (2.1%, 29/1 377), Chongqing (1.8%, 64/3 523) reported relatively high revision rates. Conclusions: The overall PJI revision rate in 34 hospitals nationwide from 2015 to 2017 is 0.96%. The hip-PJI revision rate is slightly higher than that in the knee-PJI. There are differences in revision rates among hospitals in different regions.

Functional effects of disease-associated variants reveal that the S1-M1 linker of the NMDA receptor critically controls channel opening

The short pre-M1 helix within the S1-M1 linker (also referred to as the pre-M1 linker) between the agonist-binding domain (ABD, S1) and the M1 transmembrane helix of the NMDA receptor (NMDAR) is devoid of missense variants within the healthy population but is a locus for de novo pathogenic variants associated with neurological disorders. Several de novo variants within this helix have been identified in patients presenting early in life with intellectual disability, developmental delay, and/or epilepsy. In this study, we evaluated functional properties for twenty variants within the pre-M1 linker in GRIN1, GRIN2A, and GRIN2B genes, including six novel missense variants. The effects of pre-M1 variants on agonist potency, sensitivity to endogenous allosteric modulators, response time course, channel open probability, and surface expression were assessed. Our data indicated that virtually all of the variants evaluated altered channel function, and multiple variants had profound functional consequences, which may contribute to the neurological conditions in the patients harboring the variants in this region. These data strongly suggest that the residues within the pre-M1 helix play a key role in channel gating and are highly intolerant to genetic variation.

[Observational study on perioperative outcomes of pelvic exenteration]

Objective: To investigate the surgical indications and perioperative clinical outcomes of pelvic exenteration (PE) for locally advanced, recurrent pelvic malignancies and complex pelvic fistulas. Methods: This was a descriptive study.The indications for performing PE were: (1) locally advanced, recurrent pelvic malignancy or complex pelvic fistula diagnosed preoperatively by imaging and pathological examination of a biopsy; (2)preoperative agreement by a multi-disciplinary team that non-surgical and conventional surgical treatment had failed and PE was required; and (3) findings on intraoperative exploration confirming this conclusion.Contraindications to this surgical procedure comprised cardiac and respiratory dysfunction, poor nutritional status,and mental state too poor to tolerate the procedure.Clinical data of 141 patients who met the above criteria, had undergone PE in the Sixth Affiliated Hospital of Sun Yat-sen University from January 2018 to September 2022, had complete perioperative clinical data, and had given written informed consent to the procedure were collected,and the operation,relevant perioperative variables, postoperative pathological findings (curative resection), and early postoperative complications were analyzed. Results: Of the 141 included patients, 43 (30.5%) had primary malignancies, 61 (43.3%) recurrent malignancies, 28 (19.9%) complex fistulas after radical resection of malignancies,and nine (6.4%)complex fistulas caused by benign disease. There were 79 cases (56.0%) of gastrointestinal tumors, 30 cases (21.3%) of reproductive tumors, 16 cases (11.3%) of urinary tumors, and 7 cases (5.0%) of other tumors such mesenchymal tissue tumors. Among the 104 patients with primary and recurrent malignancies, 15 patients with severe complications of pelvic perineum of advanced tumors were planned to undergo palliative PE surgery for symptom relief after preoperative assessment of multidisciplinary team; the other 89 patients were evaluated for radical PE surgery. All surgeries were successfully completed. Total PE was performed on 73 patients (51.8%),anterior PE on 22 (15.6%),and posterior PE in 46 (32.6%). The median operative time was 576 (453,679) minutes, median intraoperative blood loss 500 (200, 1 200) ml, and median hospital stay 17 (13.0,30.5)days.There were no intraoperative deaths. Of the 89 patients evaluated for radical PE surgery, the radical R0 resection was achieved in 64 (71.9%) of them, R1 resection in 23 (25.8%), and R2 resection in two (2.2%). One or more postoperative complications occurred in 85 cases (60.3%), 32 (22.7%)of which were Clavien-Dindo grade III and above.One patient (0.7%)died during the perioperative period. Conclusion: PE is a valid option for treating locally advanced or recurrent pelvic malignancies and complex pelvic fistulas.

Novel neuroactive steroids as positive allosteric modulators of NMDA receptors: mechanism, site of action, and rescue pharmacology on GRIN variants associated with neurological conditions

N-methyl-D-aspartate receptors (NMDARs) play vital roles in normal brain functions (i.e., learning, memory, and neuronal development) and various neuropathological conditions, such as epilepsy, autism, Parkinson's disease, Alzheimer's disease, and traumatic brain injury. Endogenous neuroactive steroids such as 24(S)-hydroxycholesterol (24(S)-HC) have been shown to influence NMDAR activity, and positive allosteric modulators (PAMs) derived from 24(S)-hydroxycholesterol scaffold can also enhance NMDAR function. This study describes the structural determinants and mechanism of action for 24(S)-hydroxycholesterol and two novel synthetic analogs (SGE-550 and SGE-301) on NMDAR function. We also show that these agents can mitigate the altered function caused by a set of loss-of-function missense variants in NMDAR GluN subunit-encoding GRIN genes associated with neurological and neuropsychiatric disorders. We anticipate that the evaluation of novel neuroactive steroid NMDAR PAMs may catalyze the development of new treatment strategies for GRIN-related neuropsychiatric conditions.

Dehydrocostus Lactone Reduced Malignancy of HepG2 Human Hepatocellular Carcinoma Cells via Down-Regulation of the PI3K/AKT Signaling Pathway

We studied the effect of dehydrocostus lactone (DHL) on the biological characteristics of HepG2 human hepatocellular carcinoma cells. The inhibition of cell viability by different concentrations of DHL (10, 20, 40, 80, and 160 μmol/liter) was measured using MTT test. As the determined half-maximum inhibitory concentration (IC₅₀) was 20.33 μmol/liter, DHL in a concentration of 20 μmol/liter was used in further experiments. Cell proliferation, migration, invasion ability, and apoptosis were assessed by Ki-67 immunofluorescence, Transwell assay, and TUNEL analysis. The level of p-AKT protein was determined by Western blotting. DHL significantly inhibited the viability, proliferation, migration, and invasion of HepG2 cells in comparison with the control group, and induced cells apoptosis. DHL down-regulated the expression of p-AKT protein in the HepG2 cells in comparison with the control group. PI3K/AKT signaling pathway activator 740Y-P could block the above-mentioned effects of DHL. Thus, DHL inhibits the malignancy of HepG2 human hepatocellular carcinoma cells via down-regulation of PI3K/AKT signaling pathway.

[Management and short-term outcomes of neonates born to mothers infected with SARS-CoV-2 Omicron variant]

Objective: To summarize the management and short-term outcomes of neonates delivered by mothers infected with SARS-CoV-2 Omicron variant. Methods: A retrospective study was performed on 158 neonates born to mothers infected with SARS-CoV-2 Omicron variant admitted to the isolation ward of Children's Hospital of Fudan University from March 15^th, 2022 to May 30^th, 2022. The postnatal infection control measures for these neonates, and their clinical characteristics and short-term outcomes were analyzed. They were divided into maternal symptomatic group and maternal asymptomatic group according to whether their mothers had SARS-CoV-2 symptoms. The clinical outcomes were compared between the 2 groups using Rank sum test and Chi-square test. Results: All neonates were under strict infection control measures at birth and after birth. Of the 158 neonates, 75 (47.5%) were male. The gestational age was (38⁺³±1⁺³) weeks and the birth weight was (3 201±463)g. Of the neonates included, ten were preterm (6.3%) and the minimum gestational age was 30⁺¹ weeks. Six neonates (3.8%) had respiratory difficulty and 4 of them were premature and required mechanical ventilation. All 158 neonates were tested negative for SARS-COV-2 nucleic acid by daily nasal swabs for the first 7 days. A total of 156 mothers (2 cases of twin pregnancy) infected with SARS-CoV-2 Omicron variant, the time from confirmed SARS-CoV-2 infection to delivery was 7 (3, 12) days. Among them, 88 cases (56.4%) showed clinical symptoms, but none needed intensive care treatment. The peripheral white blood cell count of the neonates in maternal symptomatic group was significantly higher than that in maternal symptomatic group (23.0 (18.7, 28.0) × 10⁹ vs. 19.6 (15.4, 36.6) × 10⁹/L, Z=2.44, P<0.05). Conclusions: Neonates of mothers infected with SARS-CoV-2 Omicron variant during third trimester have benign short-term outcomes, without intrauterine infection through vertical transmission. Strict infection control measures at birth and after birth can effectively protect these neonates from SARS-CoV-2 infection.

[Applied anatomical study and clinical application of the caudate lobe boundary and ductal system of the liver]

Objective: To explore the relationship between the hepatic caudate lobe boundary and the ductal system so as to guide the identification of the anatomical relationship during liver surgery. Methods: The specific parts were observed and the liver parenchyma was removed according to 41 cadaveric liver autopsy specimens. The critical relationship between the hepatic caudate lobe and other ducts was observed to explore the reticular duct structure. Results: The plane formed by the hepatic hilar plate and Arantius ligament served as the boundary between the caudate lobe and other hepatic lobes. The caudate lobe hepatic portal vein was composed of numerous small branches from its left and right branches. The portal vein adjacent to the vena cava was mainly derived from the left branch, and to a lesser extent from the right branch. Blood was drained straight from the caudate lobe vein into the inferior vena cava via the short hepatic vein. There were three or four bile duct branches in the caudate lobe. The main source of arterial blood flow were the left and right branches of the hepatic artery. An avascular zone of loose connective tissue was found between the caudate lobe and the retrohepatic inferior vena cava. Conclusion: The hepatic caudate lobe is an independent lobe. During hepatic caudate lobe surgery, the plane formed by the hepatic hilar plate and Arantius ligament can serve as the boundary between the caudate lobe and other hepatic lobes and be used for anatomical site identification. The duct system of the caudate lobe's is complicated, but it also has its own distinct regularity.

Mussel-Inspired Hydrogels for Fluoride Delivery and Caries Prevention

Fluoride agents hold promise for the repair and prevention of caries lesions, but their interaction with enamel is often hampered and diminished because of the dynamic wet environment in the oral cavity, which affects the efficacy of fluoride delivery and limits treatment success. We herein developed a mussel-inspired wet adhesive fluoride system (denoted TS@NaF) fabricated by the self-assembly of tannic acid (TA), silk fibroin (SF), and sodium fluoride (NaF). TS@NaF demonstrated remarkable biological stability and biocompatibility, showed reliable wet adhesion, released fluoride ions (F−) topically, and induced significant deposition of calcium fluoride (CaF2) onto enamel in vitro. Furthermore, TS@NaF provided an anticaries effect in vitro and induced a detectable increase in enamel mineral density. Advanced fluoride-releasing bioadhesives are therefore promising candidates for caries prevention and highlight the great potential of mussel-inspired dental materials in clinical applications.

Correlation between glenoid bone structure and recurrent anterior dislocation of the shoulder joint

BACKGROUND

The aim of the study was to investigate the anatomical characteristics and symmetry of the bilateral glenoid structures of Chinese people and to explore the relationship between the glenoid bone structure and recurrent anterior dislocation.

MATERIALS AND METHODS

The control group included 131 individuals with no history of shoulder dislocation. The dislocation group consisted of 131 patients with a history of unilateral shoulder dislocation. All subjects underwent computed tomography scans. Glenoid shape (pear-shaped, inverted comma-shaped, oval-shaped), width, height, depth, version angle, area, maximum fitting circle area and volume were measured.

RESULTS

There was no significant difference in normal bilateral glenoid of Chinese people (p > 0.05). There were statistically significant differences in depth, height to width ratio, maximum fitting circle area and shape between the dislocation and control groups (p < 0.05). Regression analyses showed that the glenoid depth (odds ratio [OR] 0.48; p < 0.01), the glenoid height to width ratio (OR 28.61; p < 0.01), the glenoid maximum fitting circle area (OR 1.01; p < 0.01) and the glenoid shape (p <0.05; pear-shaped OR 0.432; inverted comma-shaped OR 0.954) were associated with anterior shoulder instability. Pear-shaped and inverted comma-shaped glenoid had lower risk of recurrent anterior shoulder dislocation compared to oval glenoid. Receiver operating characteristic curve analysis showed that individuals with anterior shoulder instability had smaller glenoid depth and larger height to width ratio and the glenoid maximum fitting circle area compared with the control group.

CONCLUSIONS

The normal bilateral glenoids of Chinese people are basically symmetrical. The glenoid shape, depth, height to width ratio and maximum fitting circle area are risk factors for recurrent anterior shoulder dislocation. Evaluation of the glenoid bone structure enables more accurate prediction of the risk of recurrent shoulder dislocation.

[SWOT analysis of influenza vaccination promotion of primary care staff based on the perspective of the supplier, customer, and management]

Objective: To analyze the situation of influenza vaccination among primary healthcare workers, find out the problems, and explore the strategies and measures to promote influenza vaccination among grass-roots medical staff. Methods: From April to May 2021, key insider interviews and literature research were carried out based on the perspectives of influenza vaccine suppliers (influenza vaccine manufacturers), consumers (primary medical institutions and primary healthcare workers), and managers (governments at all levels, health administrative departments and disease prevention and control departments). The SWOT (strengths, weaknesses, opportunities, and threats) analysis technique was used to comprehensively evaluate the current situation of influenza vaccination among grass-roots healthcare workers, and a SWOT analysis matrix was established. Results: Influenza vaccination of grass-roots healthcare workers have advantages and opportunities, including primary medical and health institutions' vital influenza vaccination accessibility, influenza vaccine safety is higher, COVID-19 outbreak improves the public awareness of respiratory infectious diseases and vaccine production enthusiasm, coronavirus vaccination has strengthened the capacity of the vaccine distribution system. There are also disadvantages and threats such as the high price of influenza vaccine, insufficient supply, low awareness of influenza vaccine vaccination among grass-roots healthcare workers, lack of demand assessment mechanism on influenza vaccine, poor vaccine deployment, structural imbalance in vaccine supply in different areas, and severe vaccine waste. SWOT analysis matrix of the influenza vaccination status of grass-roots healthcare workers was established, forming dominant opportunity (SO) strategy, dominant threat (ST) strategy, inferior opportunity (WO) strategy, and inferior threat (WT) strategy. Conclusion: Measures should be taken by the supplier, the demand-side, and the management side to improve the influenza vaccine coverage rate of primary healthcare workers, but the emphasis should be on the coordination and management of the management side.

Ultrasound-assisted enzymatic hydrolysis of yeast β-glucan catalyzed by β-glucanase: Chemical and microstructural analysis

The purpose of this study was to investigate the effect of ultrasound-assisted enzymolysis on modified solubilization of yeast β-glucan and its related mechanism. The depolymerization effects of this system on the physicochemical properties and structural features of the degraded fragments were studied systematically. The structure and physicochemical properties of the samples showed that the solubility of yeast β-glucan achieved 75.35 % after modification; and ultrasonic enzymatic enhanced the degradation efficiency. The yeast β-glucan obtained after solubilization and modification owned better antioxidant activities. The yeast β-glucan particles become obviously smaller, sparsely dispersed in the aqueous solution and the stability was improved. In addition, the hydrogen bonds in yeast β-glucan native triple helix structure were partially broken. Moreover, the disruption of yeast β-glucan's original structure made it decreased thermostability and easier to dissolve in water. The atomic force microscope (AFM) imaging directly verified the branched-chain morphology of yeast β-glucan and the small-strand degradation fragments. Therefore, this research can provide a feasible and effective approach for improving solubility of water-insoluble yeast β-glucan to enlarge its food and biomedical applications.

Opportunities for Precision Treatment of GRIN2A and GRIN2B Gain-of-Function Variants in Triheteromeric N-Methyl-D-Aspartate Receptors

N-methyl-D-aspartate receptors (NMDARs) are tetrameric assemblies of two glutamate N-methyl-D-aspartate receptor subunits, GluN1 and two GluN2, that mediate excitatory synaptic transmission in the central nervous system. Four genes (GRIN2A-D) encode four distinct GluN2 subunits (GluN2A-D). Thus, NMDARs can be diheteromeric assemblies of two GluN1 plus two identical GluN2 subunits, or triheteromeric assemblies of two GluN1 subunits plus two different GluN2 subunits. An increasing number of de novo GRIN variants have been identified in patients with neurologic conditions and with GRIN2A and GRIN2B harboring the vast majority (> 80%) of variants in these cases. These variants produce a wide range of effects on NMDAR function depending upon its subunit subdomain location and additionally on the subunit composition of diheteromeric versus triheteromeric NMDARs. Increasing evidence implicates triheteromeric GluN1/GluN2A/GluN2B receptors as a major component of the NMDAR pool in the adult cortex and hippocampus. Here, we explore the ability of GluN2A- and GluN2B-selective inhibitors to reduce excess current flow through triheteromeric GluN1/GluN2A/GluN2B receptors that contain one copy of GRIN2A or GRIN2B gain-of-function variants. Our data reveal a broad range of sensitivities for variant-containing triheteromeric receptors to subunit-selective inhibitors, with some variants still showing strong sensitivity to inhibitors, whereas others are relatively insensitive. Most variants, however, retain sensitivity to non-selective channel blockers and the competitive antagonist D-(-)-2-amino-5-phosphonopentanoic acid. These results suggest that with comprehensive analysis, certain disease-related GRIN2A and GRIN2B variants can be identified as potential targets for subunit-selective modulation and potential therapeutic gain. SIGNIFICANCE STATEMENT: Triheteromeric NMDA receptors that contain one copy each of the GluN2A and GluN2B subunits show intermediate sensitivity to GluN2A- and GluN2B-selective inhibitors, making these compounds candidates for attenuating overactive, GRIN variant-containing NMDA receptors associated with neurological conditions. We show that functional evaluation of variant properties with inhibitor pharmacology can support selection of a subset of variants for which GluN2 subunit-selective agents remain effective inhibitors of variant-containing triheteromeric NMDA receptors.

Loss of IκBζ Drives Dentin Formation via Altered H3K4me3 Status

Enforced enrichment of the active promoter marks trimethylation of histone H3 lysine 4 (H3K4me3) and acetylation of histone H3 lysine 27 (H3K27ac) by inhibiting histone demethylases and deacetylases is positively associated with hard tissue formation through the induction of osteo/odontogenic differentiation. However, the key endogenous epigenetic modulator of odontoblasts to regulate the expression of genes coding dentin extracellular matrix (ECM) proteins has not been identified. We focused on nuclear factor (NF)-κB inhibitor ζ (IκBζ), which was originally identified as the transcriptional regulator of NF-κB and recently regarded as the NF-κB-independent epigenetic modulator, and found that IκBζ null mice exhibit a thicker dentin width and narrower pulp chamber, with aged mice having more marked phenotypes. At 6 mo of age, dentin fluorescent labeling revealed significantly accelerated dentin synthesis in the incisors of IκBζ null mice. In the molars of IκBζ null mice, marked tertiary dentin formation adjacent to the pulp horn was observed. Mechanistically, the expression of COL1A2 and COL1A1 collagen genes increased more in the odontoblast-rich fraction of IκBζ null mice than in wild type in vivo, similar to human odontoblast-like cells transfected with small interfering RNA for IκBζ compared with cells transfected with control siRNA in vitro. Furthermore, the direct binding of IκBζ to the COL1A2 promoter suppressed COL1A2 expression and the local active chromatin status marked by H3K4me3. Based on whole-genome identification of H3K4me3 enrichment, ECM and ECM organization-related gene loci were selectively activated by the knockdown of IκBζ, which consistently resulted in the upregulation of these genes. Collectively, this study suggested that IκBζ is the key negative regulator of dentin formation in odontoblasts by inhibiting dentin ECM- and ECM organization-related gene expression through an altered local chromatin status marked by H3K4me3. Therefore, IκBζ is a potential target for epigenetically improving the clinical outcomes of dentin regeneration therapies such as pulp capping.

A2B5-positive oligodendrocyte precursor cell transplantation improves neurological deficits in rats following spinal cord contusion associated with changes in expression of factors involved in the Notch signaling pathway

BACKGROUND

Oligodendrocyte precursor cells (OPCs) are myelinated glial cells of the central nervous system (CNS), able to regenerate oligodendrocytes and myelin. This study aimed to elucidate the effect of A2B5-positive (A2B5+) OPC transplantation in rats with spinal cord contusion (SCC) and to investigate changes in expression of various factors involved in the Notch signaling pathway after OPC transplantation.

METHODS

OPCs were obtained from induced pluripotent stem cells (iPSCs) originating from mouse embryo fibroblasts (MEFs). After identification of iPSCs and iPSC-derived OPCs, A2B5+ OPCs were transplanted into the injured site of rats with SCC one week after SCC insult. Behavioral tests evaluated motor and sensory function 7 days after OPC transplantation. Real-time quantitative polymerase chain reaction (RT-qPCR) determined the expression of various cytokines related to the Notch signaling pathway after OPC transplantation.

RESULTS

IPSC-derived OPCs were successfully generated from MEFs, as indicated by positive immunostaining of A2B5, PDGFα and NG2. Further differentiation of OPCs was identified by immunostaining of Olig2, Sox10, Nkx2.2, O4, MBP and GFAP. Importantly, myelin formation was significantly enhanced in the SCC+ OPC group and SCI-induced motor and sensory dysfunction was largely alleviated by A2B5+ OPC transplantation. Expression of factors involved in the Notch signaling pathway (Notch-1, Numb, SHARP1 and NEDD4) was significantly increased after OPC transplantation.

CONCLUSIONS

A2B5+ OPC transplantation attenuates motor and sensory dysfunction in SCC rats by promoting myelin formation, which may be associated with change in expression of factors involved in the Notch signaling pathway.

[Research progress on the correlation between small dense low-density lipoprotein-cholesterol and atherosclerotic cardiovascular disease]

Atherosclerotic cardiovascular disease (ASCVD), a series of cardiovascular diseases based on atherosclerosis, has attracted more clinical attention. However, with the increase of population-based research results, the diagnostic value of traditional blood lipid parameters such as low density lipoprotein-cholesterol (LDL-C) is showing limitations. In recent years, a large number of studies have confirmed that small dense low-density lipoprotein cholesterol (sdLDL-C) has lower affinity with low-density lipoprotein receptor, longer circulation time and easier to penetrate arterial endothelium, so it has stronger atherogenic effect. Therefore, we summarize the common detection methods of sdLDL-C, the research progress of the correlation between sdLDL-C and ASCVD risk, as well as the intervention measures and influencing factors of sdLDL-C level, in order to deepen the clinician's understanding of the role of sdLDL-C in ASCVD and achieve the early prevention, early detection and early diagnosis of chronic atherosclerosis.

Clinical and therapeutic significance of genetic variation in the GRIN gene family encoding NMDARs

Considerable genetic variation of N-methyl-d-aspartate receptors (NMDARs) has recently become apparent, with many hundreds of de novo variants identified through widely available clinical genetic testing. Individuals with GRIN variants present with neurological conditions such as epilepsy, autism, intellectual disability (ID), movement disorders, schizophrenia and behavioral disorders. Determination of the functional consequence of genetic variation for NMDARs should lead to precision therapeutics. Furthermore, genetic animal models harboring human variants have the potential to reveal mechanisms that are shared among different neurological conditions, providing strategies that may allow treatment of individuals who are refractory to therapy. Preclinical studies in animal models and small open label trials in humans support this idea. However, additional functional data for variants and animal models corresponding to multiple individuals with the same genotype are needed to validate this approach and to lead to thoughtfully designed, randomized, placebo-controlled clinical trials, which could provide data in order to determine safety and efficacy of potential precision therapeutics.

Structure, Function, and Pharmacology of Glutamate Receptor Ion Channels

Many physiologic effects of l-glutamate, the major excitatory neurotransmitter in the mammalian central nervous system, are mediated via signaling by ionotropic glutamate receptors (iGluRs). These ligand-gated ion channels are critical to brain function and are centrally implicated in numerous psychiatric and neurologic disorders. There are different classes of iGluRs with a variety of receptor subtypes in each class that play distinct roles in neuronal functions. The diversity in iGluR subtypes, with their unique functional properties and physiologic roles, has motivated a large number of studies. Our understanding of receptor subtypes has advanced considerably since the first iGluR subunit gene was cloned in 1989, and the research focus has expanded to encompass facets of biology that have been recently discovered and to exploit experimental paradigms made possible by technological advances. Here, we review insights from more than 3 decades of iGluR studies with an emphasis on the progress that has occurred in the past decade. We cover structure, function, pharmacology, roles in neurophysiology, and therapeutic implications for all classes of receptors assembled from the subunits encoded by the 18 ionotropic glutamate receptor genes. SIGNIFICANCE STATEMENT: Glutamate receptors play important roles in virtually all aspects of brain function and are either involved in mediating some clinical features of neurological disease or represent a therapeutic target for treatment. Therefore, understanding the structure, function, and pharmacology of this class of receptors will advance our understanding of many aspects of brain function at molecular, cellular, and system levels and provide new opportunities to treat patients.

Prevalence and association of mycoplasma infection in the development of coronary artery disease

Coronary heart disease (CHD) has been associated with significant morbidity and mortality worldwide. Although remain controversial, several studies have demonstrated the association of M. pneumoniae infections with atherosclerosis. We evaluated the possible association of mycoplasma infections in patients diagnosed with atherosclerosis by ELISA and PCR methods. Atherosclerotic tissue samples and blood samples were collected for the detection of mycoplasma antibodies (IgA) by ELISA from the 97 patients with coronary artery disease (CAD). M. pneumoniae specific IgA, IgG and IgM were measured by using the Anti-M. pneumoniae IgA/IgG/IgM ELISA. Detection of M. pneumoniae targeting the P1 adhesion gene was performed by PCR Acute infection of M. pneumoniae was diagnosed in 43.3% (42) of patients by PCR. The M. pneumoniae specific antibodies were detected in 36.1% (35) of patients. Twenty-five (25.8%) cases had IgG antibodies, 15 (15.5%) cases had IgM antibodies, 3 (3.1%) cases had IgA antibodies, 10 (10.3%) cases had both IgM + IgG antibodies and 1 (1%) case of each had IgM + IgA and IgG + IgA antibodies. None of the cases was positive for all three antibodies. A Pearson correlation coefficient analysis revealed an excellent correlation between the PCR and the serological results (r=0.921, p<0.001). A majority (17, 40.5%) of the M. pneumoniae positive patients are within the 41-50 years of age group, followed by 10 (23.8%) patients in the age group of 61-70 years and 2 (4.8%) patients were >70 years of age. Our study reported an unusually higher prevalence of M. pneumoniae by serological tests (36.1%) and PCR (43.3%). Although the hypothesis of the association of M. pneumoniae and CAD is yet to be proven, the unusually high prevalence of M. pneumoniae in CAD patients indicates an association, if not, in the development of atherosclerosis.

Use of dynamic contrast-enhanced MRI for the early assessment of outcome of CyberKnife stereotactic radiosurgery for patients with spinal metastases

AIM

To explore the value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for evaluating early outcomes of CyberKnife radiosurgery for spinal metastases.

MATERIALS AND METHODS

Patients with spinal metastases who were treated with CyberKnife radiosurgery from July 2018 to December 2020 were enrolled. Conventional MRI and DCE-MRI were performed before treatment and at 3 months after treatment. Patients showing disease progression were defined as the progressive disease (PD) group and those showing complete response, partial response, and stable disease were defined as the non-PD group. The haemodynamic parameters (volume transfer constant [Ktrans], rate constant [Kep], and extravascular space [Ve]) before and after treatment between the groups were analysed. Area under the curve (AUC) values were calculated.

RESULTS

A total of 27 patients with 39 independent spinal lesions were included. The median follow-up time was 18.6 months (6.2-36.4 months). There were 27 lesions in the non-PD group and 12 lesions in the PD group. Post-treatment Kep, ΔKtrans and ΔKep in the non-PD group (0.959/min, - 32.6% and -41.1%, respectively) were significantly lower than the corresponding values in PD group (1.429/min, 20.4% and -6%; p<0.05). Post-treatment Ve and ΔVe (0.223 and 27.8%, respectively) in the non-PD group were significantly higher than that of the PD group (0.165 and -13.5%, p<0.05). ΔKtrans showed the highest diagnostic efficiency, with an AUC of 0.821.

CONCLUSIONS

DCE-MRI parameters change significantly at an early stage after CyberKnife stereotactic radiosurgery for spinal metastases. DCE-MRI may be of value in determining the early treatment response.

A de novo GRIN1 Variant Associated With Myoclonus and Developmental Delay: From Molecular Mechanism to Rescue Pharmacology

N-Methyl-D-aspartate receptors (NMDARs) are highly expressed in brain and play important roles in neurodevelopment and various neuropathologic conditions. Here, we describe a new phenotype in an individual associated with a novel de novo deleterious variant in GRIN1 (c.1595C>A, p.Pro532His). The clinical phenotype is characterized with developmental encephalopathy, striking stimulus-sensitive myoclonus, and frontal lobe and frontal white matter hypoplasia, with no apparent seizures detected. NMDARs that contained the P532H within the glycine-binding domain of GluN1 with either the GluN2A or GluN2B subunits were evaluated for changes in their pharmacological and biophysical properties, which surprisingly revealed only modest changes in glycine potency but a significant decrease in glutamate potency, an increase in sensitivity to endogenous zinc inhibition, a decrease in response to maximally effective concentrations of agonists, a shortened synaptic-like response time course, a decreased channel open probability, and a reduced receptor cell surface expression. Molecule dynamics simulations suggested that the variant can lead to additional interactions across the dimer interface in the agonist-binding domains, resulting in a more open GluN2 agonist-binding domain cleft, which was also confirmed by single-molecule fluorescence resonance energy transfer measurements. Based on the functional deficits identified, several positive modulators were evaluated to explore potential rescue pharmacology.

Recurrent seizure-related GRIN1 variant: Molecular mechanism and targeted therapy

OBJECTIVE

Genetic variants in the GRIN genes that encode N-methyl-D-aspartate receptor (NMDAR) subunits have been identified in various neurodevelopmental disorders, including epilepsy. We identified a GRIN1 variant from an individual with early-onset epileptic encephalopathy, evaluated functional changes to NMDAR properties caused by the variant, and screened FDA-approved therapeutic compounds as potential treatments for the patient.

METHODS

Whole exome sequencing identified a missense variant in GRIN1. Electrophysiological recordings were made from Xenopus oocytes and transfected HEK cells to determine the NMDAR biophysical properties as well as the sensitivity to agonists and FDA-approved drugs that inhibit NMDARs. A beta-lactamase reporter assay in transfected HEK cells evaluated the effects of the variant on the NMDAR surface expression.

RESULTS

A recurrent de novo missense variant in GRIN1 (c.1923G>A, p.Met641Ile), which encodes the GluN1 subunit, was identified in a pediatric patient with drug-resistant seizures and early-onset epileptic encephalopathy. In vitro analysis indicates that GluN1-M641I containing NMDARs showed enhanced agonist potency and reduced Mg2+ block, which may be associated with the patient's phenotype. Results from screening FDA-approved drugs suggested that GluN1-M641I containing NMDARs are more sensitive to the NMDAR channel blockers memantine, ketamine, and dextromethorphan compared to the wild-type receptors. The addition of memantine to the seizure treatment regimen significantly reduced the patient's seizure burden.

INTERPRETATION

Our finding contributes to the understanding of the phenotype-genotype correlations of patients with GRIN1 gene variants, provides a molecular mechanism underlying the actions of this variant, and explores therapeutic strategies for treating GRIN1-related neurological conditions.

Coproduction of bacterial cellulose and pear vinegar by fermentation of pear peel and pomace

Bacterial cellulose (BC)-derived materials are given significant attention due to their porous fibrous texture, high crystallinity and extraordinary physico-mechanical properties. The main reason for the restricted use of BC is its high production cost. To reduce the production cost, the suitability of pear residue for the production of BC and pear vinegar was investigated. Komagataeibacter rhaeticus and Komagataeibacter intermedius with high fermentation ability screened from the surface of vinegar film of millet fermentation were used to produce BC and pear vinegar simultaneously. Through response surface optimization, the maximum yield of BC from pear residue medium was 10.94 ± 0.42 g/L, which was higher than the synthesis medium generally used for Acetobacter strains. When pear residue medium was incubated at 30 °C for 7 days, the contents of total acid and soluble solids were greater than 0.3 g/100 mL and 3%, respectively, which met the standard requirements for fruit vinegar. The flavour components of pear vinegar were determined using gas chromatography-mass spectrometry. The pear vinegar showed similar flavour characteristics to conventional fruit vinegar. This research not only solved the utilization of agricultural resources but also avoided the discharge of waste liquid when producing BC. In addition, a more environmentally friendly and less expensive way to produce BC and pear vinegar was achieved.