Prognostic Utility of Left Atrial Strain From MRI Feature Tracking in Ischemic and Nonischemic Dilated Cardiomyopathy: A Multicenter Study.

BACKGROUND. MRI-based prognostic evaluation in patients with dilated cardiomyopathy (DCM) has historically used markers of late gadolinium enhancement (LGE) and feature tracking (FT)-derived left ventricular global longitudinal strain (LVGLS). Early data indicate that FT-derived left atrial strain (LAS) parameters, including reservoir, conduit, and booster, may also have prognostic roles in such patients. OBJECTIVE. The purpose of our study was to evaluate the prognostic utility of LAS parameters, derived from MRI FT, in patients with ischemic or nonischemic DCM, including in comparison with the traditional parameters of LGE and LVGLS. METHODS. This retrospective study included 811 patients with ischemic or nonischemic DCM (median age, 60 years; 640 men, 171 women) who underwent cardiac MRI at any of five centers. FT-derived LAS parameters and LVGLS were measured using two- and four-chamber cine images. LGE percentage was quantified. Patients were assessed for a composite outcome of all-cause mortality or heart failure hospitalization. Multivariable Cox regression analyses including demographic characteristics, cardiovascular risk factors, medications used, and a wide range of cardiac MRI parameters were performed. Kaplan-Meier analyses with log-rank tests were also performed. RESULTS. A total of 419 patients experienced the composite outcome. Patients who did, versus those who did not, experience the composite outcome had larger LVGLS (-6.7% vs -8.3%, respectively; p < .001) as well as a smaller LAS reservoir (13.3% vs 19.3%, p < .001), LAS conduit (4.7% vs 8.0%, p < .001), and LAS booster (8.1% vs 10.3%, p < .001) but no significant difference in LGE (10.1% vs 11.3%, p = .51). In multivariable Cox regression analyses, significant independent predictors of the composite outcome included LAS reservoir (HR = 0.96, p < .001) and LAS conduit (HR = 0.91, p < .001). LAS booster and LGE were not significant independent predictors in the models. LVGLS was a significant independent predictor only in a model that initially included LAS booster but not the other LAS parameters. In Kaplan-Meier analysis, all three LAS parameters were significantly associated with the composite outcome (p < .001). CONCLUSION. In this multicenter study, LAS reservoir and LAS conduit were significant independent prognostic markers in patients with ischemic or nonischemic DCM, showing greater prognostic utility than the currently applied markers of LVGLS and LGE. CLINICAL IMPACT. FT-derived LAS analysis provides incremental prognostic information in patients with DCM.

Prognostic factors in 448 newly diagnosed multiple myeloma receiving bortezomib-based induction: impact of ASCT, transplant refusal and high-risk MM.

In Hong Kong, newly diagnosed multiple myeloma (NDMM) receives bortezomib-based triplet induction. Upfront autologous stem cell transplant (ASCT) is offered to transplant eligible (TE) patients (NDMM ≤ 65 years of age), unless medically unfit (TE-unfit) or refused (TE-refused). Data was retrieved for 448 patients to assess outcomes. For the entire cohort, multivariate analysis showed that male gender (p = 0.006), international staging system (ISS) 3 (p = 0.003), high lactate dehydrogenase (LDH) (p = 7.6 × 10-7) were adverse predictors for overall survival (OS), while complete response/ near complete response (CR/nCR) post-induction (p = 2.7 × 10-5) and ASCT (p = 4.8 × 10-4) were favorable factors for OS. In TE group, upfront ASCT was conducted in 252 (76.1%). Failure to undergo ASCT in TE patients rendered an inferior OS (TE-unfit p = 1.06 × 10-8, TE-refused p = 0.002) and event free survival (EFS) (TE-unfit p = 0.00013, TE-refused p = 0.002). Among TE patients with ASCT, multivariate analysis showed that age ≥ 60 (p = 8.9 × 10-4), ISS 3 (p = 0.019) and high LDH (p = 2.6 × 10-4) were adverse factors for OS. In those with high-risk features (HR cytogenetics, ISS 3, R-ISS 3), ASCT appeared to mitigate their adverse impact. Our data reaffirmed the importance of ASCT. The poor survival inherent with refusal of ASCT should be recognized by clinicians. Finally, improved outcome with ASCT in those with high-risk features warrant further studies.

Altered neutrophil-to-lymphocyte ratio in patients with non-affective first episode psychosis and its relationship with symptom severity and cognitive impairment.

Signatures of immune dysregulation as clinical biomarker for psychosis have remained unclear. We aimed to compare the Neutrophil-to-lymphocyte ratio (NLR) of patients with acute non-affective first-episode psychosis (FEP) with healthy controls after accounting for emotional states. We also explored the associations of NLR with symptom severity, onset profile and cognitive functions. The NLR was enumerated from complete blood count taken within a week of assessment. All FEP patients were rated on the Positive and Negative Syndrome Scale (PANSS) and the Clinician Global Impression-Severity (CGI-S) with verbal memory and executive functions assessed with the Cambridge Neuropsychological Test Automated Battery. Prevailing emotional state was measured with Beck Depression Inventory-II and Beck Anxiety Inventory. Out of seventy-nine consecutive FEP patients presenting to the study site, twenty-seven subjects were eligible and recruited. Twenty-seven age-/sex-matched controls were recruited. FEP patients had an NLR of 1.886 over the controls after accounting for scores on emotional states. The NLR of FEP patients was positively associated with CGI-S scores, PANSS positive symptom, disorganization and excitation scores. There was no significant correlation between NLR with the duration of untreated psychosis and cognitive performances. These findings support using NLR as a clinical biomarker in FEP, purporting further prospective study to measure NLR changes in the course of treatment.

Confined Ru Sites in a 13X Zeolite for Ultrahigh H2 Production from NH3 Decomposition.

Catalytic NH3 synthesis and decomposition offer a new promising way to store and transport renewable energy in the form of NH3 from remote or offshore sites to industrial plants. To use NH3 as a hydrogen carrier, it is important to understand the catalytic functionality of NH3 decomposition reactions at an atomic level. Here, we report for the first time that Ru species confined in a 13X zeolite cavity display the highest specific catalytic activity of over 4000 h-1 for the NH3 decomposition with a lower activation barrier, compared to most reported catalytic materials in the literature. Mechanistic and modeling studies clearly indicate that the N-H bond of NH3 is ruptured heterolytically by the frustrated Lewis pair of Ruδ+-Oδ- in the zeolite identified by synchrotron X-rays and neutron powder diffraction with Rietveld refinement as well as other characterization techniques including solid-state nuclear magnetic resonance spectroscopy, in situ diffuse reflectance infrared transform spectroscopy, and temperature-programmed analysis. This contrasts with the homolytic cleavage of N-H displayed by metal nanoparticles. Our work reveals the unprecedented unique behavior of cooperative frustrated Lewis pairs created by the metal species on the internal zeolite surface, resulting in a dynamic hydrogen shuttling from NH3 to regenerate framework Brønsted acid sites that eventually are converted to molecular hydrogen.

Metal-loaded zeolites in ammonia decomposition catalysis.

The viability of using ammonia as a hydrogen storage vector is contingent on the development of catalytic systems active for ammonia decomposition at low temperatures. Zeolite-supported metal catalysts, unlike systems based on supports like MgO or carbon nanotubes (CNTs), are crystalline and lend themselves to analytic techniques like synchrotron X-ray powder diffraction (SXRD) and Rietveld refinement, allowing precise characterisation of catalytic active sites, and therefore mechanistic elucidation. This study focuses on characterising and optimising novel zeolite-supported Ru catalysts for ammonia decomposition, with a focus on the effects of N-substitution on catalyst structure and activity. Characterisation focuses on an unsubstituted and N-substituted Ru-zeolite Y pair with NMR, FTIR, TEM, XRD, XAS, ICP, and BET, demonstrating the successful incorporation of N into the zeolite framework and an enhancement in metal dispersion upon N-substitution. A series of 18 monometallic and bimetallic catalysts is then synthesised on X and USY supports and screened for catalytic activity. Ru is identified as the most active metal for ammonia decomposition. Observed trends suggest catalyst dispersion can be increased with substantially lower metal loadings, and in particular via the formation of stably anchored oligonuclear metal clusters within the zeolite framework, as opposed to much larger nanoparticles (NPs) on its exterior, following N-substitution of the framework. DFT modelling proposes a prismatic Ru6N6 cluster fitted to XAS data. High-activity catalyst Ru-ß (N) 2.4% demonstrates comparable or better ammonia conversion by Ru wt% than recently reported catalysts in the literature at 450 °C and 30 000 WHSV.

Dispersed surface Ru ensembles on MgO(111) for catalytic ammonia decomposition.

Ammonia is regarded as an energy vector for hydrogen storage, transport and utilization, which links to usage of renewable energies. However, efficient catalysts for ammonia decomposition and their underlying mechanism yet remain obscure. Here we report that atomically-dispersed Ru atoms on MgO support on its polar (111) facets {denoted as MgO(111)} show the highest rate of ammonia decomposition, as far as we are aware, than all catalysts reported in literature due to the strong metal-support interaction and efficient surface coupling reaction. We have carefully investigated the loading effect of Ru from atomic form to cluster/nanoparticle on MgO(111). Progressive increase of surface Ru concentration, correlated with increase in specific activity per metal site, clearly indicates synergistic metal sites in close proximity, akin to those bimetallic N2 complexes in solution are required for the stepwise dehydrogenation of ammonia to N2/H2, as also supported by DFT modelling. Whereas, beyond surface doping, the specific activity drops substantially upon the formation of Ru cluster/nanoparticle, which challenges the classical view of allegorically higher activity of coordinated Ru atoms in cluster form (B5 sites) than isolated sites.

Depression screening in patients with aneurysmal subarachnoid haemorrhage and their caregivers: A systematic review.

BACKGROUND: Depression commonly occurs after aneurysmal subarachnoid haemorrhage (aSAH) which can negatively impact patients and their caregivers. Identification and validation of depression screening instruments specifically for patients with aSAH and their caregivers has not been performed. OBJECTIVES: The objectives of this study were to identify the common depression screening tools in patients with aSAH and their caregivers and to determine if they are validated for use in these populations. METHODS: Medical Subject Headings and keyword search terms were used in five electronic databases to identify randomised controlled, quasi-experimental and observational studies published between 1 January 2010 and 26 June 2022. Screening, data extraction and study quality assessments were conducted by two independent reviewers. RESULTS: Of the 3440 identified studies, 61 met inclusion, with 2 of 61 (3%) RCTs, 2 of 61 (3%) quasi-experimental, and 57 of 61 (93%) observational studies included. The majority of studies (58/61 [95%]) reported patient-only depression screening, 1 of 61 (2%) reported both patients' and caregivers' depression screening, and 2 of 61 (3%) reported caregiver-only depression screening. Nine depression screening instruments were identified. The Beck Depression Inventory-II (BDI-II) was the most commonly used (13/59; 22%), followed by the Hospital Anxiety and Depression Scale (HADS) (12/59; 20%). In the ischaemic stroke population, the BDI-II was reported to have excellent sensitivity (0.85) and specificity (0.75); the HADS was also found to have good sensitivity (0.62) and specificity (0.83) in the ischaemic stroke population. Only two depression screening instruments for caregivers were identified: HADS and Goldberg Depression Scale. Both were found to have good sensitivity (>0.80) and specificity (>0.80) in the general population. CONCLUSION: The BDI-II and HADS were the most commonly used depression screening instruments in patients with aSAH. Neither of these instruments has been specifically validated in an aSAH population. None of the nine depression instruments were validated for patients with aSAH. Due to an insufficient number of studies in caregivers' population, validity was unable to be determined.

Prevalence, Patterns, and Clinical Severity of Long COVID among Chinese Medicine Telemedicine Service Users: Preliminary Results from a Cross-Sectional Study.

INTRODUCTION: The emergence and persistence of symptoms after acute COVID-19 is expected to become a major burden on healthcare systems. We assessed the features of the post-COVID-19 Syndrome (Long COVID) burden in a cohort of COVID-19 patients during the fifth major wave in Hong Kong. METHODS: A cross-sectional study of 135 patients with confirmed COVID-19 from Feb to Apr 2022 who utilized traditional Chinese medicine telemedicine services was conducted. The COVID-19 Yorkshire Rehabilitation Scale was administered using an online survey 12 weeks after the COVID-19 infection. Prevalence of symptom severity and functional impairments were assessed to identify burdens and patterns. The correlation between symptom severity, functional impairments, patient characteristics, and overall health was evaluated. RESULTS: The mean age was 46.8 years, with 46 (34.1%) males. Symptoms, functional impairments, and overall health worsened significantly when compared to the status prior to the infection. More than 50% reported the following sequelae 12 weeks after the acute infection: breathlessness, laryngeal or airway complications, fatigue, weakness, sleep, cognition, and anxiety. The presence of a single symptom or functional impairment significantly correlated with at least seven other problems positively, except for pain. Severity tended to be higher among vulnerable groups, including those who were chronic disease patients, older, less well educated, female, or had incomplete COVID-19 vaccinations. CONCLUSIONS: Long COVID is a significant healthcare burden among telemedicine users in Hong Kong, with complex needs for symptom and functional impairment management. Designing relevant health and rehabilitation services tailored to the needs of these patients is warranted.

A multispecific antibody prevents immune escape and confers pan-SARS-CoV-2 neutralization.

Despite effective countermeasures, SARS-CoV-2 persists worldwide due to its ability to diversify and evade human immunity1. This evasion stems from amino-acid substitutions, particularly in the receptor-binding domain of the spike, that confer resistance to vaccines and antibodies 2-16. To constrain viral escape through resistance mutations, we combined antibody variable regions that recognize different receptor binding domain (RBD) sites17,18 into multispecific antibodies. Here, we describe multispecific antibodies, including a trispecific that prevented virus escape >3000-fold more potently than the most effective clinical antibody or mixtures of the parental antibodies. Despite being generated before the evolution of Omicron, this trispecific antibody potently neutralized all previous variants of concern and major Omicron variants, including the most recent BA.4/BA.5 strains at nanomolar concentrations. Negative stain electron microscopy revealed that synergistic neutralization was achieved by engaging different epitopes in specific orientations that facilitated inter-spike binding. An optimized trispecific antibody also protected Syrian hamsters against Omicron variants BA.1, BA.2 and BA.5, each of which uses different amino acid substitutions to mediate escape from therapeutic antibodies. Such multispecific antibodies decrease the likelihood of SARS-CoV-2 escape, simplify treatment, and maximize coverage, providing a strategy for universal antibody therapies that could help eliminate pandemic spread for this and other pathogens.

Vaccine-elicited murine antibody WS6 neutralizes diverse beta-coronaviruses by recognizing a helical stem supersite of vulnerability.

Immunization with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike elicits diverse antibodies, but it is unclear if any of the antibodies can neutralize broadly against other beta-coronaviruses. Here, we report antibody WS6 from a mouse immunized with mRNA encoding the SARS-CoV-2 spike. WS6 bound diverse beta-coronavirus spikes and neutralized SARS-CoV-2 variants, SARS-CoV, and related sarbecoviruses. Epitope mapping revealed WS6 to target a region in the S2 subunit, which was conserved among SARS-CoV-2, Middle East respiratory syndrome (MERS)-CoV, and hCoV-OC43. The crystal structure at 2 Å resolution of WS6 revealed recognition to center on a conserved S2 helix, which was occluded in both pre- and post-fusion spike conformations. Structural and neutralization analyses indicated WS6 to neutralize by inhibiting fusion and post-viral attachment. Comparison of WS6 with other recently identified antibodies that broadly neutralize beta-coronaviruses indicated a stem-helical supersite-centered on hydrophobic residues Phe1148, Leu1152, Tyr1155, and Phe1156-to be a promising target for vaccine design.

The impact of bortezomib-based induction in newly diagnosed multiple myeloma with chromosome 1q21 gain.

Introduction: Bortezomib has been reported to favourably impact the outcomes of t(4;14) and del(17p) in multiple myeloma (MM), but its impact on gain 1q (+1q) is unknown. Methods: To address this, 250 patients treated with bortezomib-based induction were analysed. All myeloma samples had fluorescence in situ hybridization (FISH) performed on CD138-sorted bone marrow aspirate, and plasma cells were analysed using DNA probes specific for the following chromosomal aberrations: del(13q14), del(17p), t(14;16), t(4;14), and +1q. Presence of +1q was defined as the presence of at least three copies of 1q21 at the cut off level of 20% of bone marrow plasma cells. Results: +1q identified in 167 (66.8%) and associated with t(4;14) and high lactate dehydrogenase (LDH). +1q was not associated with response rate but shorter event-free survival (EFS) (median EFS 35 vs 55 months, p = 0.05) and overall survival (OS) (median OS 74 vs 168 months, p = 0.00025). Copy number and clone size did not impact survival. Multivariate analysis showed +1q was an independent adverse factor for OS together with International Staging System (ISS)3, high LDH, del(17p) and t(4;14). When a risk score of 1 was assigned to each independent adverse factor, OS was shortened incrementally by a risk score from 0 to 4. Post-relapse/progression survival was inferior in those with +1q (median 60 vs 118 months, p = 0.000316). Autologous stem cell transplantation (ASCT) improved OS for those with +1q (median OS 96 vs 49 months, p = 0.000069). Conclusion: +1q is an adverse factor for OS in MM uniformly treated with bortezomib-based induction but was partially mitigated by ASCT. A risk scoring system comprising +1q, LDH, high-risk FISH, and ISS is a potential tool for risk stratification in MM.

Eltrombopag as frontline treatment of aplastic anaemia in routine practice: implications on cost and efficacy.

The thrombopoietin mimetic eltrombopag (EPAG) is efficacious in clinical trials of newly diagnosed moderate (M), severe (S) and very severe (vS) aplastic anaemia (AA). Its use in routine practice and resource-constrained settings is not well described. Twenty-five men and 38 women at a median age of 54 (18-86) years with newly diagnosed AA treated consecutively in a 7-year period with EPAG (N = 6), EPAG/cyclosporine (CsA) (N = 33) and EPAG/CsA/anti-thymocyte globulin (ATG) (N = 24) were analyzed. Because EPAG was not reimbursed, peak doses ranged from 25 to 200 mg/day depending on affordability. EPAG/CsA-treated patients were older (median age: 61 years) with less severe AA (MAA, N = 15; SAA, N = 14; vSAA, N = 4), whereas EPAG/CsA/ATG-treated patients were younger (median age: 44 years) with more severe AA (MAA, N = 2; SAA, N = 12, vSAA, N = 10). The overall/trilineage response rates were 83%/50% for EPAG-treated patients; 79%/42% for EPAG/CsA-treated patients and 75%/63% for EPAG/CsA/ATG-treated patients. Adverse events included grade 1 liver derangement (N = 7) and grade 1 dyspepsia (N = 3). The 5-year overall survivals/failure-free survivals were 62%/80% for the entire cohort; 55%/75% for EPAG/CsA-treated patients and 82%/78% for EPAG/CsA/ATG-treated patients. EPAG showed robust efficacy in AA in routine practice. However, EPAG dosage and combinations remain to be optimized for AA of different severities.

Vaccine-elicited murine antibody WS6 neutralizes diverse beta-coronaviruses by recognizing a helical stem supersite of vulnerability.

Immunization with SARS-CoV-2 spike elicits diverse antibodies, but can any of these neutralize broadly? Here, we report the isolation and characterization of antibody WS6, from a mouse immunized with mRNA encoding the SARS-CoV-2 spike. WS6 bound diverse beta-coronavirus spikes and neutralized SARS-CoV-2 variants, SARS-CoV, and related sarbecoviruses. Epitope mapping revealed WS6 to target a region in the S2 subunit, which was conserved among SARS-CoV-2, MERS-CoV, and hCoV-OC43. The crystal structure at 2-Å resolution of WS6 with its S2 epitope revealed recognition to center on a conserved helix, which was occluded in both prefusion and post-fusion spike conformations. Structural and neutralization analyses indicated WS6 to neutralize by inhibiting fusion, post-viral attachment. Comparison of WS6 to other antibodies recently identified from convalescent donors or mice immunized with diverse spikes indicated a stem-helical supersite - centered on hydrophobic residues Phe1148, Leu1152, Tyr1155, and Phe1156 - to be a promising target for vaccine design. HIGHLIGHTS: SARS-CoV-2 spike mRNA-immunized mouse elicited an antibody, WS6, that cross reacts with spikes of diverse human and bat beta-coronavirusesWS6 neutralizes SARS-CoV-2 variants, SARS-CoV, and related virusesCrystal structure at 2-Å resolution of WS6 in complex with a conserved S2 peptide reveals recognition of a helical epitopeWS6 neutralizes by inhibition of fusion, post-viral attachmentWS6 recognizes a supersite of vulnerability also recognized by other recently identified antibodiesHelical supersite of vulnerability comprises a hydrophobic cluster spanning three helical turns, with acid residues framing the center turnGenetic and structural analysis indicate supersite recognition to be compatible with diverse antibody ontogenies.

3D hanging spheroid plate for high-throughput CAR T cell cytotoxicity assay.

BACKGROUND: Most high-throughput screening (HTS) systems studying the cytotoxic effect of chimeric antigen receptor (CAR) T cells on tumor cells rely on two-dimensional cell culture that does not recapitulate the tumor microenvironment (TME). Tumor spheroids, however, can recapitulate the TME and have been used for cytotoxicity assays of CAR T cells. But a major obstacle to the use of tumor spheroids for cytotoxicity assays is the difficulty in separating unbound CAR T and dead tumor cells from spheroids. Here, we present a three-dimensional hanging spheroid plate (3DHSP), which facilitates the formation of spheroids and the separation of unbound and dead cells from spheroids during cytotoxicity assays. RESULTS: The 3DHSP is a 24-well plate, with each well composed of a hanging dripper, spheroid wells, and waste wells. In the dripper, a tumor spheroid was formed and mixed with CAR T cells. In the 3DHSP, droplets containing the spheroids were deposited into the spheroid separation well, where unbound and dead T and tumor cells were separated from the spheroid through a gap into the waste well by tilting the 3DHSP by more than 20°. Human epidermal growth factor receptor 2 (HER2)-positive tumor cells (BT474 and SKOV3) formed spheroids of approximately 300-350 µm in diameter after 2 days in the 3DHSP. The cytotoxic effects of T cells engineered to express CAR recognizing HER2 (HER2-CAR T cells) on these spheroids were directly measured by optical imaging, without the use of live/dead fluorescent staining of the cells. Our results suggest that the 3DHSP could be incorporated into a HTS system to screen for CARs that enable T cells to kill spheroids formed from a specific tumor type with high efficacy or for spheroids consisting of tumor types that can be killed efficiently by T cells bearing a specific CAR. CONCLUSIONS: The results suggest that the 3DHSP could be incorporated into a HTS system for the cytotoxic effects of CAR T cells on tumor spheroids.

Luteolin stimulates the NGF-induced neurite outgrowth in cultured PC12 cells through binding with NGF and potentiating its receptor signaling.

Luteolin, a flavonoid in fruits and vegetables, has neurotrophic functions without a well-characterized mechanism. Here, we hypothesize a direct interaction of luteolin with nerve growth factor (NGF); as such, the functionality of the NGF could be potentiated. The direct binding of luteolin with NGF was validated by ultra-filtration, Biacore, and docking analyses. In cultured PC12 cells, application of luteolin in combination with a low dose of NGF potentiated the NGF-induced differentiation of neurons by an increase of the differentiated cell number to 25.4 ± 4.8% (p < 0.01), as well as the increased expression of neurofilaments by 119 ± 32.1% (p < 0.05), 191 ± 12.6% (p < 0.01), and 110 ± 23.4% (p < 0.05) for NF68, NF160 and NF200, respectively. The co-treatment induced the phosphorylations of tropomyosin receptor kinase A (TrkA), extracellular signal-regulated kinase 1/2 (ERK1/2), protein kinase B (Akt), phospholipase C-γ1 (PLCγ1), and cAMP response element-binding protein (CREB) by 2 to 3 fold: these induced phosphorylations were mimicking that of a high dose of NGF. Moreover, the application of the TrkA inhibitor, K252a, blocked the luteolin-mediated induction of neurofilament expression and neurite outgrowth in cultured PC12 cells, suggesting the target specificity. The result supports the development of luteolin as a therapeutic, or preventive, agent for NGF insufficiency-associated neurodegenerative diseases.

SARS-CoV-2 S2P spike ages through distinct states with altered immunogenicity.

The SARS-CoV-2 spike is the primary target of virus-neutralizing antibodies and critical to the development of effective vaccines against COVID-19. Here, we demonstrate that the prefusion-stabilized two-proline "S2P" spike-widely employed for laboratory work and clinical studies-unfolds when stored at 4 °C, physiological pH, as observed by electron microscopy (EM) and differential scanning calorimetry, but that its trimeric, native-like conformation can be reacquired by low pH treatment. When stored for approximately 1 week, this unfolding does not significantly alter antigenic characteristics; however, longer storage diminishes antibody binding, and month-old spike elicits virtually no neutralization in mice despite inducing high ELISA-binding titers. Cryo-EM structures reveal the folded fraction of spike to decrease with aging; however, its structure remains largely similar, although with varying mobility of the receptor-binding domain. Thus, the SARS-CoV-2 spike is susceptible to unfolding, which affects immunogenicity, highlighting the need to monitor its integrity.

Mass spectrometry-based multi-omics analysis reveals the thermogenetic regulation of herbal medicine in rat model of yeast-induced fever.

ETHNOPHARMACOLOGICAL RELEVANCE: In the principle of traditional Chinese medicine (TCM), clinical usage is based on drug attributes of the herbal medicine. The cold and hot properties of TCM are classified accordingly to their pharmacological effects, such as temperature change. Herbal medicine has been used as food supplements in our daily life, and the thermogenetic regulation is one of their primary applications. However, the underlying mechanism of "cold" or "hot" stimulating effect of herbal medicine has not been fully identified. AIM OF THE STUDY: Thermogenetic regulation and classification of herbal medicine of hot/cold herbs were determined by rat model of yeast-induced fever. MATERIALS AND METHODS: Here, a novel method in classifying and characterizing cold- and hot-herbal medicines was established by analyses of mass spectrometry (MS)-based metabolomics and lipidomics from the serum of herbal extract-treated rats. The yeast-induced inflammatory rats were used as the model system, which were subjected to the treatments of cold- or hot-herbal medicine. RESULTS: The multi-omics approach identified the clustering of metabolites from cold and hot herb-treated rat serum by using partial least squares discriminant analysis (PLS-DA), and which subsequently identified that the 8-h treatment was the metabolic perturbation point of herb-mediated thermogenesis. Meanwhile, the levels of identified metabolites in the serum, i.e. lysoPE, lysoPC and carnitine, showed a positive relationship with the regulation of body temperature; while the levels of amino acid, fatty acid and bile acid were contrary correlated with the temperature change. In addition, the differential expressed metabolites were subjected to pathway enrichment and network analyses in revealing the possible action mechanism of herbal medicines in relating to thermogenetic regulation. CONCLUSION: The developed MS-based omics provides a new insight in characterizing the properties of cold/hot herbal medicine.

Fraudulent antibiotic products on the market for aquaculture use.

Antibiotics in aquaculture are used to treat bacterial infections. In order for these products to work effectively fish need to be properly dosed. One of the emerging issues in aquaculture is under-dosing large populations of fish with antibiotics. This happens inadvertently for a number of reasons including the use of fraudulent medications. In this study we evaluated 17 antibiotic products (8 florfenicol and 9 oxytetracycline brands purchased in Asia) by HPLC to determine if the product labels accurately reflected the active pharmaceutical ingredient (API) in the package. We determined authenticity scores for different batches of products at two separate laboratories by comparing the observed API to the label API concentration. We found that 48 % of the antibiotic batches had authenticity scores below 80 % (i.e. observed API in package was at least 20 % less than the label API concentration). Further, there were 9 or the 31 batches of drugs tested had no measureable API. Some products had variation in their authenticity scores between batches making it difficult to rely on a brand. The price of florfenicol products may help identify products with low authenticity scores, but in the case of oxytetracycline, the price of all the products tested was relatively similar. The findings in this study suggest that not all florfenicol and oxytetracycline antibiotic products on the market in Asia have API concentrations indicated on their labels. This could be problematic for medicating fish on aquaculture farms.

Determining the coordination environment and electronic structure of polymer-encapsulated cobalt phthalocyanine under electrocatalytic CO2 reduction conditions using in situ X-Ray absorption spectroscopy.

Encapsulating cobalt phthalocyanine (CoPc) within the coordinating polymer poly-4-vinylpyridine (P4VP) results in a catalyst-polymer composite (CoPc-P4VP) that selectively reduces CO2 to CO at fast rates at low overpotential. In previous studies, we postulated that the enhanced selectively for CO over H2 production within CoPc-P4VP compared to the parent CoPc complex is due to a combination of primary, secondary, and outer-coordination sphere effects imbued by the encapsulating polymer. In this work, we perform in situ electrochemical X-ray absorption spectroscopy measurements to study the oxidation state and coordination environment of Co as a function of applied potential for CoPc, CoPc-P4VP, and CoPc with an axially-coordinated py, CoPc(py). Using in situ X-ray absorption near edge structure (XANES) we provide experimental support for our previous hypothesis that Co changes from a 4-coordinate square-planar geometry in CoPc to a mostly 5-coordinate species in CoPc(py) and CoPc-P4VP. The coordination environment of CoPc-P4VP is potential-independent but pH-dependent, suggesting that the axial coordination of pyridyl groups in P4VP to CoPc is modulated by the protonation of the polymer. Finally, we show that at low potential the oxidation state of Co in the 4-coordinate CoPc is different from that in the 5-coordinate CoPc(py), suggesting that the primary coordination sphere modulates the site of reduction (metal-centered vs. ligand centered) under catalytically-relevant conditions.

Recent Advances of Precise Cu Nanoclusters in Microporous Materials.

This minireview highlights some recent advances in the rational design of precise Cu nanoclusters supported on microporous materials, including zeolites and metal-organic frameworks. The development of comprehensive characterisation techniques enables scientists to elucidate the structure-activity relationship of these catalysts, which aids the subsequent engineering of more superior catalytic systems at an atomistic perspective.