Quantitative Assessment of Tumor Contact with Neurogenic Zones and Its Effects on Survival: Insights beyond Traditional Predictors.

So far, the cellular origin of glioblastoma (GBM) needs to be determined, with prevalent theories suggesting emergence from transformed endogenous stem cells. Adult neurogenesis primarily occurs in two brain regions: the subventricular zone (SVZ) and the subgranular zone (SGZ) of the hippocampal dentate gyrus. Whether the proximity of GBM to these neurogenic niches affects patient outcome remains uncertain. Previous studies often rely on subjective assessments, limiting the reliability of those results. In this study, we assessed the impact of GBM's relationship with the cortex, SVZ and SGZ on clinical variables using fully automated segmentation methods. In 177 glioblastoma patients, we calculated optimal cutpoints of minimal distances to the SVZ and SGZ to distinguish poor from favorable survival. The impact of tumor contact with neurogenic zones on clinical parameters, such as overall survival, multifocality, MGMT promotor methylation, Ki-67 and KPS score was also examined by multivariable regression analysis, chi-square test and Mann-Whitney-U. The analysis confirmed shorter survival in tumors contacting the SVZ with an optimal cutpoint of 14 mm distance to the SVZ, separating poor from more favorable survival. In contrast, tumor contact with the SGZ did not negatively affect survival. We did not find significant correlations with multifocality or MGMT promotor methylation in tumors contacting the SVZ, as previous studies discussed. These findings suggest that the spatial relationship between GBM and neurogenic niches needs to be assessed differently. Objective measurements disprove prior assumptions, warranting further research on this topic.

Superoxide Dismutase-Mimetic Polyphenol-Based Carbon Dots for Multimodal Bioimaging and Treatment of Atopic Dermatitis.

Polyphenols have been investigated for their potential to mitigate inflammation in the context of atopic dermatitis (AD). In this study, epigallocatechin-3-gallate (EGCG)-based carbon dots (EGCG@CDs) were developed to enhance transdermal penetration, reduce inflammation, recapitulate superoxide dismutase (SOD) activity, and provide antimicrobial effects for AD treatment. The water-soluble EGCG@CDs in a few nanometers size exhibit a negative zeta potential, making them suitable for effective transdermal penetration. The fluorescence properties, including an upconversion effect, make EGCG@CDs suitable imaging probes for both in vitro and in vivo applications. By mimicking the SOD enzyme, EGCG@CDs scavenge reactive oxygen species (ROS) and actively produce hydrogen peroxide through a highly catalytic capability toward the oxygen reduction reaction, resulting in the inhibition of bacterial growth. The enhanced antioxidant properties, high charge mobility, and various functional groups of EGCG@CDs prove effective in reducing intracellular ROS in an in vitro AD model. In the mouse AD model, EGCG@CDs incorporated into a hydrogel actively penetrated the epidermal layer, leading to ROS scavenging, reduced mast cell activation, and histological recovery of skin barriers. This research represents the versatile potential of EGCG@CDs in addressing AD and advancing tissue engineering.

Longitudinal immune kinetics of COVID-19 booster versus primary series vaccination: Insight into the annual vaccination strategy.

Background: Data on the durability of booster dose immunity of COVID-19 vaccines are relatively limited. Methods: Immunogenicity was evaluated for up to 9-12 months after the third dose of vaccination in 94 healthy adults. Results: Following the third dose, the anti-spike immunoglobulin G (IgG) antibody response against the wild-type was boosted markedly, which decreased gradually over time. However, even 9-12 months after the booster dose, both the median and geometric mean of anti-spike IgG antibody levels were higher than those measured 4 weeks after the second dose. Breakthrough infection during the Omicron-dominant period boosted neutralizing antibody titers against Omicron sublineages (BA.1 and BA.5) and the ancestral strain. T-cell immune response was efficiently induced and maintained during the study period. Conclusions: mRNA vaccine booster dose elicited durable humoral immunity for up to 1 year after the third dose and T-cell immunity was sustained during the study period, supporting an annual COVID-19 vaccination strategy.

Decellularized brain extracellular matrix based NGF-releasing cryogel for brain tissue engineering in traumatic brain injury.

Traumatic brain injuries(TBI) pose significant challenges to human health, specifically neurological disorders and related motor activities. After TBI, the injured neuronal tissue is known for hardly regenerated and recovered to their normal neuron physiology and tissue compositions. For this reason, tissue engineering strategies that promote neuronal regeneration have gained increasing attention. This study explored the development of a novel neural tissue regeneration cryogel by combining brain-derived decellularized extracellular matrix (ECM) with heparin sulfate crosslinking that can perform nerve growth factor (NGF) release ability. Morphological and mechanical characterizations of the cryogels were performed to assess their suitability as a neural regeneration platform. After that, the heparin concnentration dependent effects of varying NGF concentrations on cryogel were investigated for their controlled release and impact on neuronal cell differentiation. The results revealed a direct correlation between the concentration of released NGF and the heparin sulfate ratio in cryogel, indicating that the cryogel can be tailored to carry higher loads of NGF with heparin concentration in cryogel that induced higher neuronal cell differentiation ratio. Furthermore, the study evaluated the NGF loaded cryogels on neuronal cell proliferation and brain tissue regeneration in vivo. The in vivo results suggested that the NGF loaded brain ECM derived cryogel significantly affects the regeneration of brain tissue. Overall, this research contributes to the development of advanced neural tissue engineering strategies and provides valuable insights into the design of regenerative cryogels that can be customized for specific therapeutic applications.

A new exceptionally well-preserved basal actinopterygian fish in the juvenile stage from the Upper Triassic Amisan Formation of South Korea.

The study of the large paraphyletic group of extinct 'palaeoniscoid' fishes has shed light on the diversity and evolutionary history of basal actinopterygians. However, only a little ontogenetic information about 'palaeoniscoids' is known because their records in the early stages of development are scarce. Here, we report on a growth series of 'palaeoniscoids' in the juvenile stage from the Upper Triassic Amisan Formation of South Korea. Fourteen specimens, including five counterpart specimens, represent a new taxon, Megalomatia minima gen. et sp. nov., exhibiting ontogeny and exceptional preservation with the eyes possibly containing the crystalline lens, the otoliths, and the lateral line canals without covering scales. This discovery allows us to discuss the adaptations and evolution of basal actinopterygians in more detail than before. The otoliths in situ of Megalomatia support the previous interpretation that basal actinopterygians have a sagitta as the largest otolith. The trunk lateral line canal, which runs under the scales instead of passing through them, represents a plesiomorphic gnathostome trait. Notably, the large protruded eyes suggest that Megalomatia probably has binocular vision, which would have played a significant role in targeting and catching prey with the primitive jaw structure. In addition, the firstly formed skeletal elements such as the jaws, pectoral girdle, and opercular series, and the posteroanterior pattern of squamation development are likely linked to the adaptation of young individuals to increase their viability for feeding, respiration, and swimming.

Gold-Nanolayer-Derived Zincophilicity Suppressing Metallic Zinc Dendrites and Its Efficacy in Improving Electrochemical Stability of Aqueous Zinc-Ion Batteries.

Herein, an Au-coating layer adjusted on the surface of a Zn metal electrode that effectively suppresses the dendrite growth as well as the mechanisms underlying the dendrite suppression as a result of the zincophilic character of Au is introduced. For the Au-coated Zn metal symmetric cell, uniform deposition of Zn-derived compounds was revealed by operando synchrotron tomography. Microscopic studies demonstrate that the Au-coating layer is induced to form a new Zn-Au alloy during the initial Zn deposition, resulting in stabilized long-term stripping/plating of Zn via the 'embracing effect' that intimately accommodates Zn deposition for further cycles. This property supports the successful operation of symmetrical cells up to 50 mA cm-2 . According to Zn electrodeposition simulation, it is verified that the suppression of dendrite growth is responsible for the electro-conducting Au nanolayer that uniformly distributes the electric field and protects the Zn electrode from corrosion, ultimately promoting uniform Zn growth. The compatibility of the Au-coating layer for full cell configuration is verified using NaV3 O8 as a cathode material over 1 000 cycles. This finding provides a new pathway for the enhancement of the electrochemical performance of ZIBs by suppressing the dendritic growth of Zn by means of a zincophilic Au nanolayer.

Implantable Self-Reporting Stents for Detecting In-Stent Restenosis and Cardiac Functional Dynamics.

Despite the increasing number of stents implanted each year worldwide, patients remain at high risk for developing in-stent restenosis. Various self-reporting stents have been developed to address this challenge, but their practical utility has been limited by low sensitivity and limited data collection. Herein, we propose a next-generation self-reporting stent that can monitor blood pressure and blood flow inside the blood arteries. This proposed self-reporting stent utilizes a larger inductor coil encapsulated on the entire surface of the stent strut, resulting in a 2-fold increase in the sensing resolution and coupling distance between the sensor and external antenna. The dual-pressure sensors enable the detection of blood flow in situ. The feasibility of the proposed self-reporting stent is successfully demonstrated through in vivo analysis in rats, verifying its biocompatibility and multifunctional utilities. This multifunctional self-reporting stent has the potential to greatly improve cardiovascular care by providing real-time monitoring and unprecedented insight into the functional dynamics of the heart.

Evolution of neutralizing antibodies through vaccination and breakthrough infections in the era of COVID-19 endemicity.

Despite a high vaccination rate, the COVID-19 pandemic continues with immune-evading Omicron variants. The success of additional antigenic stimulation through breakthrough infection (BI) and updated vaccination in overcoming antigenic imprinting needs to be determined. Participants in a long-term follow-up cohort of healthcare worker (HCW) vaccinee were categorized according to their infection/vaccination status. Anti-SARS-CoV-2 spike/nucleocapsid protein antibodies were measured, and plaque reduction neutralization tests (PRNTs) against wild-type (WT), BA.5, BN.1, and XBB.1.5 were conducted. The neutralization activity of intravenous immunoglobulin (IVIG) products was evaluated to assess the immune status of the general population. Ninety-five HCWs were evaluated and categorized into seven groups. The WT PRNT ND50 value was highest regardless of infection/vaccination status, and groups with recent antigenic stimulation showed high PRNT titers overall. Groups with double Omicron stimulation, either by BI plus BA.4/5 bivalent vaccination or repeated BI, exhibited significantly higher BA.5 and BN.1 PRNT to WT PRNT ratios than those with single Omicron stimulation. Overall group immunity was estimated to be boosted in January 2023, reflecting the effect of the BA.4/5 bivalent booster and additional BIs, but slightly declined in June 2023. A substantial increase in the antibody concentrations of IVIG products was noticed in 2022, and recently produced IVIG products exhibited a substantial level of cross-reactive neutralizing activity against emerging variants. Neutralizing activity against emerging variants could be enhanced by repeated antigenic stimulation via BI and/or updated vaccination. Overall group immunity was elevated accordingly, and IVIG products showed substantial activity against circulating strains.

Longitudinal kinetics of neutralizing antibodies against circulating SARS-CoV-2 variants and estimated level of group immunity of booster-vaccinated individuals during omicron-dominated COVID-19 outbreaks in the Republic of Korea, 2022.

The coronavirus disease 2019 pandemic persisted for 3 years and is now transitioning to endemicity. We illustrated the change in group immunity induced by vaccination (monovalent vaccines) and breakthrough infections (BIs) in a healthcare worker (HCW) cohort. Five sampling points were analyzed: before the third dose and 1, 3, 5, and 8 months after the vaccination. The last two points corresponded roughly to 1 and 4 months after omicron BA.1/BA.2 BI. A semi-quantitative anti-spike binding antibody (Sab) assay and plaque reduction neutralization test (PRNT) against circulating variants were conducted. A linear regression model was utilized to deduce correlation equations. Baseline characteristics and antibody titers after the third dose were not different between 106 HCWs with or without BI (54/52). One month after the third dose, BA.1 PRNT increased with wild-type (WT), but 3 months after the third dose, it decreased more rapidly than WT PRNT. After BI, BA.1 PRNT increased robustly and waned slower than WT. A linear equation of waning kinetics was deduced between log10Sab and months, and the slope became gradual after BI. The estimated BA.5 PRNT titers at the beginning of the BA.5 outbreak were significantly higher than the BA.1 PRNT titers of the initial BA.1/BA.2 wave, which might be associated with the smaller size of the BA.5 wave. BA.1/BA.2 BI after the third dose elicited robust and broad neutralizing activity, preferentially maintaining cross-neutralizing longevity against BA.1 and BA.5. The estimated kinetics provide an overview of group immunity through the third vaccination and BA.1/BA.2 BI, correlating with the actual outbreaks. IMPORTANCE This study analyzed changes in group immunity induced by coronavirus disease 2019 (COVID-19) vaccination and BA.1/BA.2 breakthrough infections (BIs) in a healthcare worker cohort. We investigated the longitudinal kinetics of neutralizing antibodies against circulating variants and confirmed that BA.1/BA.2 BIs enhance the magnitude and durability of cross-neutralization against BA.1 and BA.5. Correlation equations between semi-quantitative anti-spike antibody and plaque reduction neutralization test titers were deduced from the measured values using a linear regression model. Based on the equations, group immunity was estimated to last up to 11 months following the third dose of the COVID-19 vaccine. The estimated group immunity suggests that the augmented immunity and flattened waning slope through BI could correlate with the overall outbreak size. Our findings could provide a better understanding to establish public health strategies against future endemicity.

Separation and Identification of an Antimicrobial Substance from Schisandra chinensis Extract against Streptococcus mutans KCCM 40105 Strain.

This study aimed to isolate and identify antibacterial compounds from Schisandra chinensis (S. chinensis) that are effective against the Streptococcus mutans KCCM 40105 strain. First, S. chinensis was extracted using varying concentrations of ethanol, and the resulting antibacterial activity was evaluated. The 30% ethanol extract of S. chinensis showed high activity. The fractionation and antibacterial activity of a 30% ethanol extract from S. chinensis were examined using five different solvents. Upon investigation of the antibacterial activity of the solvent fraction, the water and butanol fractions showed high activity, and no significant difference was found. Therefore, the butanol fraction was chosen for material exploration using silica gel column chromatography. A total of 24 fractions were obtained from the butanol portion using silica gel chromatography. The fraction with the highest antibacterial activity was Fr 7. From Fr 7, thirty-three sub-fractions were isolated, and sub-fraction 17 showed the highest level of antibacterial activity. A total of five peaks were obtained through the pure separation of sub-fraction 17 using HPLC. Peak 2 was identified as a substance exhibiting a high level of antibacterial activity. Based on the results of UV spectrometry, 13C-NMR, 1H-NMR, LC-MS, and HPLC analyses, the compound corresponding to peak number 2 was identified as tartaric acid.

Heterometallic Gd-Dy Formate Frameworks for Enhanced Magnetocaloric Properties.

Lanthanide-based metal-organic frameworks (MOFs) have great potential as magnetic refrigerants under cryogenic conditions and are comparable to conventional alloys and magnetic nanoparticles. In particular, MOFs with Gd3+ ions behave as excellent magnetic refrigerants because of their large spin ground states. However, the major drawback of Gd3+-based MOFs is that they are not affected by the ligand material owing to the excessively large spin-only magnetic moment; therefore, their application is limited to the cryogenic region in the magnetic cooling field. In this study, we report the magnetic properties and magnetocaloric effect (MCE) resulting from heterogenized MOFs obtained from the reaction of Gd3+ and Dy3+ ions and their varied molar composition with the formate ligand. For GdxDy1-x-(HCOO)3, where 0 ≤ x ≤ 1, the isothermal magnetic entropy change (ΔSm) increased with the increase in the fraction of Gd in the heterogenized MOFs. Meanwhile, with increasing Dy contents, the maximum peak temperature of ΔSm is shifted to a higher temperature while preserving a relatively high ΔSm value of 22.35 J·kg-1 K-1 at T = 7 K for an applied field change (ΔH) of 7 T despite the anisotropy and crystalline electric field effects. Furthermore, it was confirmed that the samples with a Dy content of 75% or more maintained the ΔSm operating temperature longer. Therefore, the current approach of including Dy3+ ions in lanthanide compounds provides the possibility of further extending the operating temperature of magnetic cooling materials from cryogenic temperatures.

Obstructive sleep apnea risk and hearing impairment among occupational noise-exposed male workers.

This study aimed to investigate the association between obstructive sleep apnea (OSA) risk and hearing impairment among workers exposed to occupational noise. A cross-sectional study was conducted among 607 healthy male workers at a tire-manufacturing factory. The subjects underwent audiometric testing, and their OSA risk was examined based on the STOP-Bang questionnaire. Hearing impairment was defined as a hearing threshold >25 dB hearing level (HL) in any frequency of 1, 2, 3 and 4 kHz in either ear. High OSA risk was defined as a STOP-bang score of ≥3. Hearing thresholds at 1, 2, 3 and 4 kHz in both ears were significantly higher among workers with high OSA risk than among those with low OSA risk after adjusting for confounders. Multiple logistic regression analysis examining the association of OSA risk and STOP-Bang score with hearing impairment revealed an odds ratio of 1.738 (95% confidence interval [CI] 1.113-2.713, p = 0.015) and 1.256 (95% CI 1.031-1.529, p = 0.023), respectively, after adjusting for confounders. In addition, when the hearing impairment was reclassified into high- and low-frequency hearing impairment, a statistically significant OR was seen for high-frequency hearing impairment. In conclusion, high OSA risk was associated with hearing impairment in occupational noise-exposed workers, especially in the high-frequency range of 3 and 4 kHz. More efforts are required to improve the management of OSA and its risk factors to preserve hearing in occupational noise-exposed workers.

Regenerative Potential of Bone Morphogenetic Protein 7-Engineered Mesenchymal Stem Cells in Ligature-Induced Periodontitis.

Periodontitis is an oral disease caused by bacterial infection that has stages according to the severity of tissue destruction. The advanced stage of periodontitis presents irreversible destruction of soft and hard tissues, which finally results in loss of teeth. When conventional treatment modalities show limited results, tissue regeneration therapy is required in patients with advanced periodontitis. In the present study, we aimed to evaluate the effect of bone marrow-derived mesenchymal stem cells (BM-MSCs) delivering bone morphogenetic protein 7 (BMP7) on tissue regeneration in a periodontitis model. BMP7 is a member of the BMP family that shows bone-forming ability; however, BMPs rapid clearing and degradation and unproven efficacy make it difficult to apply it in clinical dentistry. To overcome this, we established BMP7-expressing engineered BM-MSCs (BMP7-eBMSCs) that showed superior osteogenic differentiation potential when subcutaneously transplanted with a biphasic calcium phosphate scaffold into immunocompromised mice. Furthermore, the efficacy of BMP7-eBMSC transplantation for periodontal tissue regeneration was evaluated in a rat ligature-induced periodontitis model. Upon measuring two-dimensional and three-dimensional amounts of regenerated alveolar bone using microcomputed tomography, the amounts were found to be significantly higher in the BMP7-eBMSC transplantation group than in the eBMSC transplantation group. Most importantly, fibrous periodontal ligament (PDL) tissue regeneration was also achieved upon BMP7-eBMSC transplantation, which was evaluated by calculating the modified relative connective tissue attachment. The amount of connective tissue attachment in the BMP7-eBMSC transplantation group was significantly higher than that in the ligature-induced periodontitis group, although the increase was comparable between the BMP7-eBMSC and human PDL stem cell transplantation groups. Taken together, our results suggested that sustainable release of BMP7 induces periodontal tissue regeneration and that transplantation of BMP7-eBMSCs is a feasible treatment option for periodontal regeneration. Impact Statement Periodontitis is the second most common human dental disease affecting chronic systemic diseases. Despite the tremendous efforts trying to cure the damaged periodontal tissues using tissue engineering technologies, a definitive regenerative method has not been in consensus. Researchers are seeking more feasible and abundant source of mesenchymal stem cells (MSCs), and furthermore, how to use reliable growth factors under more efficient control are the issues to be solved. In this study, we aimed to evaluate the effect of bone morphogenetic protein 7 (BMP7) gene delivering bone marrow-derived MSCs on periodontal tissue regeneration to evaluate the efficacy of BMP7 and engineered BMSCs for periodontal tissue regeneration.

Penoscrotal defect reconstruction using loco-regional flaps in treatment of extramammary Paget's disease: Experience and suggestion of a simplified algorithm.

BACKGROUND: Reconstruction of penoscrotal defects resulted from margin-controlled excision of extramammary Paget's disease (EMPD) remains challenging, due to its unpredictably varying extents. The present study aimed to investigate outcomes of reconstruction of penoscrotal defects following radical excision of EMPD and to introduce a simplified algorithm for selecting reconstruction strategies. METHODS: Patients with penoscrotal EMPD who were treated with wide excision and subsequent reconstruction from 2009 to 2020 were reviewed. Their demographics, operation-related characteristics, and postoperative outcomes were evaluated. RESULTS: In total, 46 patients with a mean age of 64.9 years (range, 44-85 years) were analyzed. An average size of defects was 129.6 cm2 (range, 8-900 cm2 ). The most frequently involving anatomical subunit was scrotum, followed by suprapubic area and penile shaft. Twenty-six patients had defects spanning multiple subunits. The most commonly used reconstruction methods for each anatomical subunit were internal pudendal artery perforator (IPAP) flaps and/or scrotal flaps for scrotal defects, superficial external pudendal artery perforator (SEPAP) flaps for suprapubic defects, and skin grafts for penile defects. In all but four cases, successful reconstruction was achieved with combination of those reconstruction options. No major complications developed except for one case of marginal flap necrosis. All patients were satisfied with their aesthetic and functional results. CONCLUSIONS: Diverse penoscrotal defects following excision of EMPD could be solidly reconstructed with combination of several loco-regional options. A simplified algorithm using in combination of IPAP flap, SEPAP flap, scrotal flap, and skin graft may enable efficient and reliable reconstruction of penoscrotal EMPD defects.

A new species of torrent catfish, Liobagrusgeumgangensis (Teleostei, Siluriformes, Amblycipitidae), from Korea.

In a recent survey of populations of the Korean torrent catfish Liobagrus, a distinctive species was discovered from the Geum River and its tributaries flowing into the western coast of Korea, and here described as a new species, L.geumgangensissp. nov. It is distinguishable from other congeners by a combination of the following characters: I, 8 pectoral fin-rays; 52-56 caudal-fin rays; a relatively short occiput to dorsal-fin origin distance (6.9-9.8% SL); a short pelvic-fin insertion to anal-fin origin distance (11.9-17.3% SL); a long dorsal-fin base (10.6-13.5% SL); 8-9 gill rakers; 5-8 serrations on the pectoral fin; the body and fins are dark yellow, the margins of the dorsal, anal, and caudal fins are dark brown, but the outermost rim is faintly yellow. Analysis of the cytb gene also confirmed that L.geumgangensis is a monophyletic lineage distinct from other congeners.

Dual action of a tyrosinase-mesoporous silica nanoparticle complex for synergistic tissue adhesion.

Bridging biological tissues for immediate adhesion and long-term sustainability was accomplished using a combination of mesoporous silica nanoparticles (MSNs) and tyrosinase. Tyrosinase-loaded MSNs provided rapid physical adsorption, while tyrosinase within MSNs induced enzymatic chemical bond gluing of tissues. This synergistic strategy has robust potential in tissue adhesives for clinical settings.

A non-avian dinosaur with a streamlined body exhibits potential adaptations for swimming.

Streamlining a body is a major adaptation for aquatic animals to move efficiently in the water. Whereas diving birds are well known to have streamlined bodies, such body shapes have not been documented in non-avian dinosaurs. It is primarily because most known non-avian theropods are terrestrial, barring a few exceptions. However, clear evidence of streamlined bodies is absent even in the purported semiaquatic groups. Here we report a new theropod, Natovenator polydontus gen. et sp. nov., from the Upper Cretaceous of Mongolia. The new specimen includes a well-preserved skeleton with several articulated dorsal ribs that are posterolaterally oriented to streamline the body as in diving birds. Additionally, the widely arched proximal rib shafts reflect a dorsoventrally compressed ribcage like aquatic reptiles. Its body shape suggests that Natovenator was a potentially capable swimming predator, and the streamlined body evolved independently in separate lineages of theropod dinosaurs.

Estimation of SARS-CoV-2 Neutralizing Activity and Protective Immunity in Different Vaccine Types Using Three Surrogate Virus Neutralization Test Assays and Two Semiquantitative Binding Assays Targeting the Receptor-Binding Domain.

Estimating neutralizing activity in vaccinees is crucial for predicting the protective effect against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As the plaque reduction neutralization test (PRNT) requires a biosafety level 3 facility, it would be advantageous if surrogate virus neutralization test (sVNT) assays and binding assays could predict neutralizing activity. Here, five different assays were evaluated with respect to the PRNT in vaccinees: three sVNT assays from GenScript, Boditech Med, and SD Biosensor and two semiquantitative binding assays from Roche and Abbott. The vaccinees were subjected to three vaccination protocols: homologous ChAdOx1, homologous BNT162b2, and heterologous administration. The ability to predict a 50% neutralizing dose (ND50) of ≥20 largely varied among the assays, with the binding assays showing substantial agreement (kappa, ~0.90) and the sVNT assays showing relatively poor performance, especially in the ChAdOx1 group (kappa, 0.33 to 0.97). The ability to predict an ND50 value of ≥118.25, indicating a protective effect, was comparable among different assays. Applying optimal cutoffs based on Youden's index, the kappa agreements were greater than 0.60 for all assays in the total group. Overall, relatively poor performance was demonstrated in the ChAdOx1 group, owing to low antibody titers. Although there were intra-assay differences related to the vaccination protocols, as well as interassay differences, all assays demonstrated fair performance in predicting the protective effect using the new cutoffs. This study demonstrates the need for a different cutoff for each assay to appropriately determine a higher neutralizing titer and suggests the clinical feasibility of using various assays for estimation of the protective effect. IMPORTANCE The coronavirus disease 2019 (COVID-19) pandemic continues to last, despite high COVID-19 vaccination rates. As many people experience breakthrough infection after prior infection and/or vaccination, estimating the neutralization activity and predicting the protective effect are major issues of concern. However, since standard neutralization tests are not available in most clinical laboratories, it would be beneficial if commercial assays could predict these aspects. In this study, we evaluated the performance of three sVNT assays and two semiquantitative binding assays targeting the receptor-binding domain with respect to the PRNT. Our results suggest that these assays could be used for predicting the protective effect by adjusting the cutoffs.

Isolation and Identification of Fisetin: An Antioxidative Compound Obtained from Rhus verniciflua Seeds.

The goal of this study was to provide basic data for the development of functional food and health materials for Rhus verniciflua (R. verniciflua) seeds. We investigated an antioxidative compound obtained from these seeds. Solvent fractionation was carried out on a 50%-ethanol extract of the seeds. The DPPH and ABTS radical-scavenging activity and superoxide dismutase (SOD) activity were measured, and high antioxidant activity was seen in the ethyl acetate fraction. The antioxidant compounds in the ethyl acetate fraction were isolated using silica-gel column chromatography by adjusting the solvent between chloroform and methanol. Fraction numbers 2-7 showed activity of more than 50%. Next, primary column chromatography was used to mix and concentrate the fractions that demonstrated antioxidant activity. The fractions were then subjected to secondary column chromatography to obtain subfraction 4, which showed high antioxidant activity. The separation of subfraction 4 was then performed using high-performance liquid chromatography (HPLC). Three peaks were identified and peak number 2 was judged to be the primary antioxidative compound, which was then isolated by pure separation. Finally, the purified subfraction peak number 2 was identified as a fisetin compound by liquid chromatography-mass spectrometry (LC-MS), nuclear magnetic resonance (NMR), and HPLC.