Dissecting Detergent-Insoluble Proteome in Alzheimer's Disease by TMTc-Corrected Quantitative Mass Spectrometry.

Protein aggregation of amyloid-ß peptides and tau are pathological hallmarks of Alzheimer's disease (AD), which are often resistant to detergent extraction and thus enriched in the insoluble proteome. However, additional proteins that coaccumulate in the detergent-insoluble AD brain proteome remain understudied. Here, we comprehensively characterized key proteins and pathways in the detergent-insoluble proteome from human AD brain samples using differential extraction, tandem mass tag (TMT) labeling, and two-dimensional LC-tandem mass spectrometry. To improve quantification accuracy of the TMT method, we developed a complement TMT-based strategy to correct for ratio compression. Through the meta-analysis of two independent detergent-insoluble AD proteome datasets (8914 and 8917 proteins), we identified 190 differentially expressed proteins in AD compared with control brains, highlighting the pathways of amyloid cascade, RNA splicing, endocytosis/exocytosis, protein degradation, and synaptic activity. To differentiate the truly detergent-insoluble proteins from copurified background during protein extraction, we analyzed the fold of enrichment for each protein by comparing the detergent-insoluble proteome with the whole proteome from the same AD samples. Among the 190 differentially expressed proteins, 84 (51%) proteins of the upregulated proteins (n = 165) were enriched in the insoluble proteome, whereas all downregulated proteins (n = 25) were not enriched, indicating that they were copurified components. The vast majority of these enriched 84 proteins harbor low-complexity regions in their sequences, including amyloid-ß, Tau, TARDBP/TAR DNA-binding protein 43, SNRNP70/U1-70K, MDK, PTN, NTN1, NTN3, and SMOC1. Moreover, many of the enriched proteins in AD were validated in the detergent-insoluble proteome by five steps of differential extraction, proteomic analysis, or immunoblotting. Our study reveals a resource list of proteins and pathways that are exclusively present in the detergent-insoluble proteome, providing novel molecular insights to the formation of protein pathology in AD.

Effects of inflammation, childhood adversity, and psychiatric symptoms on brain morphometrical phenotypes in bipolar II depression.

BACKGROUND: The neuroanatomical alteration in bipolar II depression (BDII-D) and its associations with inflammation, childhood adversity, and psychiatric symptoms are currently unclear. We hypothesize that neuroanatomical deficits will be related to higher inflammation, greater childhood adversity, and worse psychiatric symptoms in BDII-D. METHODS: Voxel- and surface-based morphometry was performed using the CAT toolbox in 150 BDII-D patients and 155 healthy controls (HCs). Partial Pearson correlations followed by multiple comparison correction was used to indicate significant relationships between neuroanatomy and inflammation, childhood adversity, and psychiatric symptoms. RESULTS: Compared with HCs, the BDII-D group demonstrated significantly smaller gray matter volumes (GMVs) in frontostriatal and fronto-cerebellar area, insula, rectus, and temporal gyrus, while significantly thinner cortices were found in frontal and temporal areas. In BDII-D, smaller GMV in the right middle frontal gyrus (MFG) was correlated with greater sexual abuse (r = -0.348, q < 0.001) while larger GMV in the right orbital MFG was correlated with greater physical neglect (r = 0.254, q = 0.03). Higher WBC count (r = -0.227, q = 0.015) and IL-6 levels (r = -0.266, q = 0.015) was associated with smaller GMVs in fronto-cerebellar area in BDII-D. Greater positive symptoms was correlated with larger GMVs of the left middle temporal pole (r = 0.245, q = 0.03). CONCLUSIONS: Neuroanatomical alterations in frontostriatal and fronto-cerebellar area, insula, rectus, temporal gyrus volumes, and frontal-temporal thickness may reflect a core pathophysiological mechanism of BDII-D, which are related to inflammation, trauma, and psychiatric symptoms in BDII-D.

Interleukin-1ß moderates the relationships between middle frontal-mACC/insular connectivity and depressive symptoms in bipolar II depression.

The functional alterations of the brain in bipolar II depression (BDII-D) and their clinical and inflammatory associations are understudied. We aim to investigate the functional brain alterations in BDII-D and their relationships with inflammation, childhood adversity, and psychiatric symptoms, and to examine the moderating effects among these factors. Using z-normalized amplitude of low-frequency fluctuation (zALFF), we assessed the whole-brain resting-state functional activity between 147 BDII-D individuals and 150 healthy controls (HCs). Differential ALFF regions were selected as seeds for functional connectivity analysis to observe brain connectivity alterations resulting from abnormal regional activity. Four inflammatory cytokines including interleukin (IL)-6, IL-1ß, tumor necrosis factor (TNF)-α, and C-reactive protein (CRP) and five clinical scales including Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale (HAMA), Positive and Negative Syndrome Scale (PANSS), Columbia-Suicide Severity Rating Scale (C-SSRS), and Childhood Trauma Questionnaire (CTQ) were tested and assessed in BDII-D. Partial correlations with multiple comparison corrections identified relationships between brain function and inflammation, childhood adversity, and psychiatric symptoms. Moderation analysis was conducted based on correlation results and previous findings. Compared to HCs, BDII-D individuals displayed significantly lower zALFF in the superior and middle frontal gyri (SFG and MFG) and insula, but higher zALFF in the occipital-temporal area. Only the MFG and insula-related connectivity exhibited significant differences between groups. Within BDII-D, lower right insula zALFF value correlated with higher IL-6, CRP, and emotional adversity scores, while lower right MFG zALFF was related to higher CRP and physical abuse scores. Higher right MFG-mid-anterior cingulate cortex (mACC) connectivity was associated with higher IL-1ß. Moreover, IL-1ß moderated associations between higher right MFG-mACC/insula connectivity and greater depressive symptoms. This study reveals that abnormal functional alterations in the right MFG and right insula were associated with elevated inflammation, childhood adversity, and depressive symptoms in BDII-D. IL-1ß may moderate the relationship between MFG-related connectivity and depressive symptoms.

Lp-PLA2 (Lipoprotein-Associated Phospholipase A2) Deficiency Lowers Cholesterol Levels and Protects Against Atherosclerosis in Rabbits.

BACKGROUND: Elevated plasma Lp-PLA2 (lipoprotein-associated phospholipase A2) activity is closely associated with an increased risk of cardiovascular events. However, whether and how Lp-PLA2 is directly involved in the pathogenesis of atherosclerosis is still unclear. To examine the hypothesis that Lp-PLA2 could be a potential preventative target of atherosclerosis, we generated Lp-PLA2 knockout rabbits and investigated the pathophysiological functions of Lp-PLA2. METHODS: Lp-PLA2 knockout rabbits were generated using CRISPR/Cas9 system to assess the role of Lp-PLA2 in plasma lipids regulation and identify its underlying molecular mechanisms. Homozygous knockout rabbits along with wild-type rabbits were fed a cholesterol-rich diet for up to 14 weeks and their atherosclerotic lesions were compared. Moreover, the effects of Lp-PLA2 deficiency on the key cellular behaviors in atherosclerosis were assessed in vitro. RESULTS: When rabbits were fed a standard diet, Lp-PLA2 deficiency led to a significant reduction in plasma lipids. The decreased protein levels of SREBP2 (sterol regulatory element-binding protein 2) and HMGCR (3-hydroxy-3-methylglutaryl coenzyme A reductase) in livers of homozygous knockout rabbits indicated that the cholesterol biosynthetic pathway was impaired with Lp-PLA2 deficiency. In vitro experiments further demonstrated that intracellular Lp-PLA2 efficiently enhanced SREBP2-related cholesterol biosynthesis signaling independently of INSIGs (insulin-induced genes). When fed a cholesterol-rich diet, homozygous knockout rabbits exhibited consistently lower level of hypercholesterolemia, and their aortic atherosclerosis lesions were significantly reduced by 60.2% compared with those of wild-type rabbits. The lesions of homozygous knockout rabbits were characterized by reduced macrophages and the expression of inflammatory cytokines. Macrophages of homozygous knockout rabbits were insensitive to M1 polarization and showed reduced DiI-labeled lipoprotein uptake capacity compared with wild-type macrophages. Lp-PLA2 deficiency also inhibited the adhesion between monocytes and endothelial cells. CONCLUSIONS: These results demonstrate that Lp-PLA2 plays a causal role in regulating blood lipid homeostasis and Lp-PLA2 deficiency protects against dietary cholesterol-induced atherosclerosis in rabbits. Lp-PLA2 could be a potential target for the prevention of atherosclerosis.

Genetic analysis of a family affected by congenital myasthenic syndrome due to a Novel mutation in the SLC5A7 gene.

BACKGROUND: Mutations in the SLC5A7 gene cause congenital myasthenia, a rare genetic disorder. Mutation points in the SLC5A7 gene differ among individuals and encompass various genetic variations; however, exon deletion variants have yet to be reported in related cases. This study aims to explore the clinical phenotype and genetic traits of a patient with congenital myasthenic syndrome due to SLC5A7 gene variation and those of their family members. CASE PRESENTATION: We describe a case of a Chinese male with congenital myasthenic syndrome presenting fluctuating limb weakness. Genetic testing revealed a heterozygous deletion mutation spanning exons 1-9 in the SLC5A7 gene. QPCR confirmed a deletion in exon 9 of the SLC5A7 gene in the patient's mother and brother. Clinical symptoms of myasthenia improved following treatment with pyridostigmine. CONCLUSION: Exons 1, 5, and 9 of the SLC5A7 gene encode the choline transporter's transmembrane region. Mutations in these exons can impact the stability and plasma membrane levels of the choline transporter. Thus, a heterozygous deletion in exons 1-9 of the SLC5A7 gene could be the pathogenic cause for this patient. In patients exhibiting fluctuating weakness, positive RNS, and seronegativity for myasthenia gravis antibodies, a detailed family history should be considered, and enhanced genetic testing is recommended to determine the cause.

Cross-species recognition of SARS-CoV-2 to bat ACE2.

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged as a major threat to global health. Although varied SARS-CoV-2-related coronaviruses have been isolated from bats and SARS-CoV-2 may infect bat, the structural basis for SARS-CoV-2 to utilize the human receptor counterpart bat angiotensin-converting enzyme 2 (bACE2) for virus infection remains less understood. Here, we report that the SARS-CoV-2 spike protein receptor binding domain (RBD) could bind to bACE2 from Rhinolophus macrotis (bACE2-Rm) with substantially lower affinity compared with that to the human ACE2 (hACE2), and its infectivity to host cells expressing bACE2-Rm was confirmed with pseudotyped SARS-CoV-2 virus and SARS-CoV-2 wild virus. The structure of the SARS-CoV-2 RBD with the bACE2-Rm complex was determined, revealing a binding mode similar to that of hACE2. The analysis of binding details between SARS-CoV-2 RBD and bACE2-Rm revealed that the interacting network involving Y41 and E42 of bACE2-Rm showed substantial differences with that to hACE2. Bats have extensive species diversity and the residues for RBD binding in bACE2 receptor varied substantially among different bat species. Notably, the Y41H mutant, which exists in many bats, attenuates the binding capacity of bACE2-Rm, indicating the central roles of Y41 in the interaction network. These findings would benefit our understanding of the potential infection of SARS-CoV-2 in varied species of bats.

Evaluation of a Pooling Chemoproteomics Strategy with an FDA-Approved Drug Library.

Chemoproteomics is a key platform for characterizing the mode of action for compounds, especially for targeted protein degraders such as proteolysis targeting chimeras (PROTACs) and molecular glues. With deep proteome coverage, multiplexed tandem mass tag-mass spectrometry (TMT-MS) can tackle up to 18 samples in a single experiment. Here, we present a pooling strategy for further enhancing the throughput and apply the strategy to an FDA-approved drug library (95 best-in-class compounds). The TMT-MS-based pooling strategy was evaluated in the following steps. First, we demonstrated the capability of TMT-MS by analyzing more than 15 000 unique proteins (> 12 000 gene products) in HEK293 cells treated with five PROTACs (two BRD/BET degraders and three degraders for FAK, ALK, and BTK kinases). We then introduced a rationalized pooling strategy to separate structurally similar compounds in different pools and identified the proteomic response to 14 pools from the drug library. Finally, we validated the proteomic response from one pool by reprofiling the cells via treatment with individual drugs with sufficient replicates. Interestingly, numerous proteins were found to change upon drug treatment, including AMD1, ODC1, PRKX, PRKY, EXO1, AEN, and LRRC58 with 7-hydroxystaurosporine; C6orf64, HMGCR, and RRM2 with Sorafenib; SYS1 and ALAS1 with Venetoclax; and ATF3, CLK1, and CLK4 with Palbocilib. Thus, pooling chemoproteomics screening provides an efficient method for dissecting the molecular targets of compound libraries.

Quantitative Lipidomics and Spatial MS-Imaging Uncovered Neurological and Systemic Lipid Metabolic Pathways Underlying Troglomorphic Adaptations in Cave-Dwelling Fish.

Sinocyclocheilus represents a rare, freshwater teleost genus endemic to China that comprises the river-dwelling surface fish and the cave-dwelling cavefish. Using a combinatorial approach of quantitative lipidomics and mass-spectrometry imaging (MSI), we demonstrated that neural compartmentalization of lipid distribution and lipid metabolism is associated with the evolution of troglomorphic traits in Sinocyclocheilus. Attenuated docosahexaenoic acid (DHA) biosynthesis via the Δ4 desaturase pathway led to reductions in DHA-phospholipids in cavefish cerebellum. Instead, cavefish accumulates arachidonic acid-phospholipids that may disfavor retinotectal arbor growth. Importantly, MSI of sulfatides coupled with immunostaining of myelin basic protein and transmission electron microscopy images of hindbrain axons revealed demyelination in cavefish raphe serotonergic neurons. Demyelination in cavefish parallels the loss of neuroplasticity governing social behavior such as aggressive dominance. Outside the brain, quantitative lipidomics and qRT-PCR revealed systemic reductions in membrane esterified DHAs in the liver, attributed to suppression of genes along the Sprecher pathway (elovl2, elovl5, and acox1). Development of fatty livers was observed in cavefish; likely mediated by an impeded mobilization of storage lipids, as evident in the diminished expressions of pnpla2, lipea, lipeb, dagla, and mgll; and suppressed ß-oxidation of fatty acyls via both mitochondria and peroxisomes as reflected in the reduced expressions of cpt1ab, hadhaa, cpt2, decr1, and acox1. These neurological and systemic metabolic adaptations serve to reduce energy expenditure, forming the basis of recessive evolution that eliminates nonessential morphological and behavioral traits and giving cavefish a selective advantage to thrive in caves where proper resource allocation becomes a major determinant of survival.

Discovery of N-Acyl Amino Acids and Novel Related N-, O-Acyl Lipids by Integrating Molecular Networking and an Extended In Silico Spectral Library.

Research on novel bioactive lipids has garnered increasing interest. Although lipids can be identified by searching mass spectral libraries, the discovery of novel lipids remains challenging as the query spectra of such lipids are not included in libraries. In this study, we propose a strategy to discover novel carboxylic acid-containing acyl lipids by integrating molecular networking with an extended in silico spectral library. Derivatization was performed to improve the response of this method. The tandem mass spectrometry spectra enriched by derivatization facilitated the formation of molecular networking and 244 nodes were annotated. We constructed consensus spectra for these annotations based on molecular networking and developed an extended in silico spectral library based on these consensus spectra. The spectral library included 6879 in silico molecules covering 12,179 spectra. Using this integration strategy, 653 acyl lipids were discovered. Among these, O-acyl lactic acids and N-lactoyl amino acid-conjugated lipids were annotated as novel acyl lipids. Compared with conventional methods, our proposed method allows for the discovery of novel acyl lipids, and extended in silico libraries significantly increase the size of the spectral library.

Analysis of temporal metabolic rewiring for human respiratory syncytial virus infection by integrating metabolomics and proteomics.

INTRODUCTION: Human respiratory syncytial virus (HRSV) infection causes significant morbidity, and no effective treatments are currently available. Viral infections induce substantial metabolic changes in the infected cells to optimize viral production. Metabolites that reflect the interactions between host cells and viruses provided an opportunity to identify the pathways underlying severe infections. OBJECTIVE: To better understand the metabolic changes caused by HRSV infection, we analyzed temporal metabolic profiling to provide novel targets for therapeutic strategies for inhaled HRSV infection. METHODS: The epithelial cells and BALB/c mice were infected with HRSV. Protein and mRNA levels of inflammation factors were measured by using quantitative reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay. Untargeted metabolomics, lipidomics and proteomics were performed using liquid chromatography coupled with mass spectrometry to profile the metabolic phenotypic alterations in HRSV infection. RESULTS: In this study, we evaluated the inflammatory responses in vivo and in vitro and investigated the temporal metabolic rewiring of HRSV infection in epithelial cells. We combined metabolomics and proteomic analyses to demonstrate that the redox imbalance was further provoked by increasing glycolysis and anaplerotic reactions. These responses created an oxidant-rich microenvironment that elevated reactive oxygen species levels and exacerbated glutathione consumption. CONCLUSION: These observations indicate that adjusting for metabolic events during a viral infection could represent a valuable approach for reshaping the outcome of infections.

Using a Clinical Decision Support System to Improve Anticoagulation in Patients with Nonvalve Atrial Fibrillation in China's Primary Care Settings: A Feasibility Study.

Background: To primarily investigate the effect of using a clinical decision support system (CDSS) in community health centers in Shanghai, China, on the proportion of patients prescribed guideline-directed antithrombotic therapy. This study also gauged the general practitioner (GP)'s acceptance of the CDSS who worked in the atrial fibrillation (AF) special consulting room of the CDSS group. Methods: This was a prospective cohort study that included a semistructured interview and a feasibility study for a cluster-randomized controlled trial. Eligible patients who sought medical care in the AF special consulting rooms in two community health centers in Shanghai, China, between April 1, 2020, and October 1, 2020, were enrolled, and their medical records from the enrollment date, up to October 1, 2021, were extracted. Based on whether the GPs in the AF special consulting rooms of the two sites used the CDSS or not, we classified the two sites as a software group and a control group. The CDSS could automatically assess the risks of stroke and bleeding and provide suggestions on treatment, follow-up, adjustment of anticoagulants or dosage, and other items. The primary outcome was the proportion of patients prescribed guideline-directed antithrombotic therapy. We also conducted a semistructured interview with the GP in the AF special consulting rooms of the software group regarding the acceptance of the CDSS and suggestions on the optimization of the CDSS and the study protocol of the cluster-randomized controlled trial in the future. Results: Eighty-four patients completed the follow-up. The mean age of these subjects was 75.71 years, the median time of clinical visits was six times per person, and the follow-up duration was 15 months. The basic demographics were similar between the two groups, except for age (t = 2.109, p = 0.038) and the HAS-BLED score (χ 2 = 4.363, p = 0.037). The primary outcome in the software group was 8.071 times higher than that in the control group (adjusted odds ratio (OR) = 8.071, 95% confidence interval (2.570-25.344), p < 0.001). The frequency of consultation between groups was not significantly different (p = 0.981). It seemed that the incidence of adverse clinical events in the software group was lower than that in the control group. The main reason for dropouts in both groups was "following up in other hospitals." The GP in the AF special consulting rooms of the software group accepted the CDSS well. Conclusions: The findings indicated that it was feasible to further promote the CDSS in the study among community health centers in China. The use of the CDSS might improve the proportion of patients prescribed guideline-directed antithrombotic therapy. The GP in the AF special consulting room of the software group showed a positive attitude toward the CDSS.

Brain-derived subgroups of bipolar II depression associate with inflammation and choroid plexus morphology.

AIM: Elevated inflammation and larger choroid plexus (ChP) volume has been previously identified in mood disorders. Connections between inflammation, ChP, and clinical symptoms in bipolar II depression (BDII-D) are unclear. Data-driven clustering based on neuroanatomical phenotypes may help to elucidate neurobiological associations in BDII-D. METHODS: Inflammatory cytokines, clinical symptoms, and neuroanatomical features were assessed in 150 BDII-D patients. Sixty-eight cortical surface area (SA) and 19 subcortical volumes were extracted using FreeSurfer. The ChP volume was segmented manually using 3D Slicer. Regularized canonical correlation analysis was used to identify significantly correlated components between cortical SA and subcortical volumes (excluding the ChP), followed by k-means clustering to define brain-derived subgroups of BDII-D. Low-grade inflammation was derived by averaging the standardized z scores of interleukin (IL)-6, IL-1ß, and tumor necrosis factor-α (TNF-α), which were computed to create a composite z-value score. Partial Pearson correlations followed by multiple comparison correction were conducted to explore associations between inflammation, clinical symptoms, and ChP volume. RESULTS: Subgroup I demonstrated smaller subcortical volume and cortical SA, higher inflammation, and larger ChP volume compared with subgroup II. Greater ChP volume was associated with a higher low-grade inflammation (mean r = 0.289, q = 0.003), CRP (mean r = 0.249, q = 0.007), IL-6 (left r = 0.200, q = 0.03), and TNF-α (right r = 0.226, q = 0.01), while greater IL-1ß was significantly associated with severe depressive symptoms in BDII-D (r = 0.218, q = 0.045). CONCLUSIONS: Neuroanatomically-derived subgroups of BDII-D differed in their inflammation levels and ChP volume. These findings suggest an important role of elevated peripheral inflammation and larger ChP in BDII-D.

29-Plex tandem mass tag mass spectrometry enabling accurate quantification by interference correction.

Tandem mass tag (TMT) mass spectrometry is a mainstream isobaric chemical labeling strategy for profiling proteomes. Here we present a 29-plex TMT method to combine the 11-plex and 18-plex labeling strategies. The 29-plex method was examined with a pooled sample composed of 1×, 3×, and 10× Escherichia coli peptides with 100× human background peptides, which generated two E. coli datasets (TMT11 and TMT18), displaying the distorted ratios of 1.0:1.7:4.2 and 1.0:1.8:4.9, respectively. This ratio compression from the expected 1:3:10 ratios was caused by co-isolated TMT-labeled ions (i.e., noise). Interestingly, the mixture of two TMT sets produced MS/MS spectra with unique features for the noise detection: (i) in TMT11-labeled spectra, TMT18-specific reporter ions (e.g., 135N) were shown as the noise; (ii) in TMT18-labeled spectra, the TMT11/TMT18-shared reporter ions (e.g., 131C) typically exhibited higher intensities than TMT18-specific reporter ions, due to contaminated TMT11-labeled ions in these shared channels. We further estimated the noise levels contributed by both TMT11- and TMT18-labeled peptides, and corrected reporter ion intensities in every spectrum. Finally, the anticipated 1:3:10 ratios were largely restored. This strategy was also validated using another 29-plex sample with 1:5 ratios. Thus the 29-plex method expands the TMT throughput and enhances the quantitative accuracy.

Deep Single-Cell-Type Proteome Profiling of Mouse Brain by Nonsurgical AAV-Mediated Proximity Labeling.

Proteome profiling is a powerful tool in biological and biomedical studies, starting with samples at bulk, single-cell, or single-cell-type levels. Reliable methods for extracting specific cell-type proteomes are in need, especially for the cells (e.g., neurons) that cannot be readily isolated. Here, we present an innovative proximity labeling (PL) strategy for single-cell-type proteomics of mouse brain, in which TurboID (an engineered biotin ligase) is used to label almost all proteins in a specific cell type. This strategy bypasses the requirement of cell isolation and includes five major steps: (i) constructing recombinant adeno-associated viruses (AAVs) to express TurboID driven by cell-type-specific promoters, (ii) delivering the AAV to mouse brains by direct intravenous injection, (iii) enhancing PL labeling by biotin administration, (iv) purifying biotinylated proteins, followed by on-bead protein digestion, and (v) quantitative tandem-mass-tag (TMT) labeling. We first confirmed that TurboID can label a wide range of cellular proteins in human HEK293 cells and optimized the single-cell-type proteomic pipeline. To analyze specific brain cell types, we generated recombinant AAVs to coexpress TurboID and mCherry proteins, driven by neuron- or astrocyte-specific promoters and validated the expected cell expression by coimmunostaining of mCherry and cellular markers. Subsequent biotin purification and TMT analysis identified ∼10,000 unique proteins from a few micrograms of protein samples with excellent reproducibility. Comparative and statistical analyses indicated that these PL proteomes contain cell-type-specific cellular pathways. Although PL was originally developed for studying protein-protein interactions and subcellular proteomes, we extended it to efficiently tag the entire proteomes of specific cell types in the mouse brain using TurboID biotin ligase. This simple, effective in vivo approach should be broadly applicable to single-cell-type proteomics.

Rare left-sided accessory pathway successfully ablated with atrial insertion site at the left-side fossa ovalis.

INTRODUCTION: Left-sided accessory pathway (AP) with atrial insertion away from the annulus is an atypical variation. Conventional mapping and ablation performed along mitral annulus (MA) is usually ineffective. METHODS: A 14-year-old girl without structural heart disease presented with recurrent episodes of sudden onset palpitations and electrocardiogram (ECG) showed a narrow QRS complex tachycardia. RESULTS: Electrophysiology study (EPS) was done and anterograde atrioventricular reentrant tachycardia (AVRT) with AP was diagnosed. Conventional mapping and ablation performed along TA and MA was failed. 3D-activation mapping found the retrograde atrial insertion site of AP on the left atrium fossa ovalis (FO), and AP was successfully abolished by radiofrequency ablation at that site. CONCLUSION: As reported, this patient is the first report of ablating a left-sided AP with retrograde atrial insertion on the left atrium FO.

Transcriptomic Profile Identifies Hippocampal Sgk1 as the Key Mediator of Ovarian Estrogenic Regulation on Spatial Learning and Memory and Aß Accumulation.

Previous studies have shown that ovarian estrogens are involved in the occurrence and pathology of Alzheimer's disease (AD) through regulation on hippocampal synaptic plasticity and spatial memory; however, the underlying mechanisms have not yet been elucidated at the genomic scale. In this study, we established the postmenopausal estrogen-deficient model by ovariectomy (OVX). Then, we used high-throughput Affymetrix Clariom transcriptomics and found 143 differentially expressed genes in the hippocampus of OVX mice with the absolute fold change ≥ 1.5 and P < 0.05. GO analysis showed that the highest enrichment was seen in long-term memory. Combined with the response to steroid hormone enrichment and GeneMANIA network prediction, the serum and glucocorticoid-regulated kinase 1 gene (Sgk1) was found to be the most potent candidate for ovarian estrogenic regulation. Sgk1 overexpression viral vectors (oSgk1) were then constructed and injected into the hippocampus of OVX mice. Morris water maze test revealed that the impaired spatial learning and memory induced by OVX was rescued by Sgk1 overexpression. Additionally, the altered expression of synaptic proteins and actin remodeling proteins and changes in CA1 spine density and synapse density induced by OVX were also significantly reversed by oSgk1. Moreover, the OVX-induced increase in Aß-producing BACE1 and Aß and the decrease in insulin degrading enzyme were significantly reversed by oSgk1. The above results show that multiple pathways and genes are involved in ovarian estrogenic regulation of the function of the hippocampus, among which Sgk1 may be a novel potent target against estrogen-sensitive hippocampal dysfunctions, such as Aß-initiated AD.

N-glycosylation of PD-1 promotes binding of camrelizumab.

PD-1 is a highly glycosylated inhibitory receptor expressed mainly on T cells. Targeting of PD-1 with monoclonal antibodies (MAbs) to block the interaction with its ligand PD-L1 has been successful for the treatment of multiple tumors. However, polymorphisms at N-glycosylation sites of PD-1 exist in the human population that might affect antibody binding, and dysregulated glycosylation has been observed in the tumor microenvironment. Here, we demonstrate varied N-glycan composition in PD-1, and show that the binding affinity of camrelizumab, a recently approved PD-1-specific MAb, to non-glycosylated PD-1 proteins from E. coli is substantially decreased compared with glycosylated PD-1. The structure of the camrelizumab/PD-1 complex reveals that camrelizumab mainly utilizes its heavy chain to bind to PD-1, while the light chain sterically inhibits the binding of PD-L1 to PD-1. Glycosylation of asparagine 58 (N58) promotes the interaction with camrelizumab, while the efficiency of camrelizumab to inhibit the binding of PD-L1 is substantially reduced for glycosylation-deficient PD-1. These results increase our understanding of how glycosylation affects the activity of PD-1-specific MAbs during immune checkpoint therapy.

Transition-Metal- and Light-Free Generation of an Iminyl Radical: Facile Approach to Oxindoles and Isoquinolinediones with a Quaternary Carbon Center via Cyanoalkylarylation.

We have developed an efficient and non-toxic method for the environmental-friendly generation of an iminyl radical from cyclobutanone oxime ester via direct thermolysis in the absence of light, transition metals, "tin", and other activators. This redox-neutral cyanoalkylarylation protocol enjoys a wide substrate scope and a good functional group tolerance, providing facile access to oxindoles and isoquinolinediones with a quaternary carbon center that are difficult to prepare by traditional methods.

Characterization of acetolactate decarboxylase of Streptococcus thermophilus and its stereoselectivity in decarboxylation of α-hydroxy-ß-ketoacids.

Acetolactate decarboxylase (ALDC) is a well-characterized catabolic enzyme catalyzes the decarboxylation of (±)-acetolactate to produce a single product, (R)-acetoin. It can also convert other racemic α-hydroxy-ß-ketoacids to corresponding α -hydroxyketones in R-configuration. In this work, we prepared ALDC of Streptococcus thermophilus (StALDC) and explored its stereoselectivity on different substrates. The enzyme displays no enantioselectivity on substrate (±)-acetolactate, but R-selectivity on product acetoin, which are identical with the data reported for various ALDCs. When compound (±)-2-propionyl-2-hydroxybutyrate is used as a substrate, however, the enzyme exhibits S-selectivity on both substrate and product, namely it can only decarboxylate (S)-2-propionyl-2-hydroxybutyrate to generate (S)-4-hydroxy-3-hexanone rather than its R-isomer, which is totally discriminate from the data published for the ALDC of Bacillus subtilis. As far as we know, this is the first time that substrate dependent enantioselectivity of ALDC is reported and the feature of StALDC is also discussed on the basis of homology modeling and molecular docking experiments.

Common and distinct patterns of gray matter alterations in young adults with borderline personality disorder and major depressive disorder.

Young adults with borderline personality disorder (BPD) and major depressive disorder (MDD) have a relatively high comorbidity rate; however, whether they share a neurobiological basis remains controversial. Although previous studies have reported respective brain alterations, the common and distinct gray matter changes between two disorders are still inconsistent. We conducted a meta-analysis using anisotropic effect size-based algorithms (ASE-SDM) to identify consistent findings from whole-brain voxel-based morphometry (VBM) studies of gray matter volume (GMV) in 274 young adults (< 45 years old) with BPD and 1576 with MDD. Compared with healthy controls, the young adults with BPD showed GMV reduction mainly in the prefrontal cortex including the inferior frontal gyrus and superior frontal gyrus, medial temporal network, and insula, whereas the MDD showed GMV alteration in the visual network (fusiform gyrus and inferior temporal gyrus), sensorimotor network (bilateral postcentral gyrus (PoCG) and right cerebellum) and left caudate nucleus. The GMV differences between these two disorders were concentrated in the left orbitofrontal cortex, cingulate cortex, right insula, and cerebellum. The meta-regression of the MDD group showed a negative association between disease duration and the right middle cingulate gyrus as well as negative associations between depressive symptoms and brain regions of the right cerebellum and the left PoCG. Our results identified common and distinct patterns of GMV alteration between BPD and MDD, which may provide neuroimage evidence for the disorder comorbidity mechanisms and partly indicate the similar and different biological features in emotion regulation of the two disorders. This study was registered with PROSPERO (CRD42020212758).