LRRC15 inhibits SARS-CoV-2 cellular entry in trans.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection is mediated by the entry receptor angiotensin-converting enzyme 2 (ACE2). Although attachment factors and coreceptors facilitating entry are extensively studied, cellular entry factors inhibiting viral entry are largely unknown. Using a surfaceome CRISPR activation screen, we identified human LRRC15 as an inhibitory attachment factor for SARS-CoV-2 entry. LRRC15 directly binds to the receptor-binding domain (RBD) of spike protein with a moderate affinity and inhibits spike-mediated entry. Analysis of human lung single-cell RNA sequencing dataset reveals that expression of LRRC15 is primarily detected in fibroblasts and particularly enriched in pathological fibroblasts in COVID-19 patients. ACE2 and LRRC15 are not coexpressed in the same cell types in the lung. Strikingly, expression of LRRC15 in ACE2-negative cells blocks spike-mediated viral entry in ACE2+ cell in trans, suggesting a protective role of LRRC15 in a physiological context. Therefore, LRRC15 represents an inhibitory attachment factor for SARS-CoV-2 that regulates viral entry in trans.

Supersymmetric Spectral Form Factor and Euclidean Black Holes.

The late-time behavior of spectral form factor (SFF) encodes the inherent discreteness of a quantum system, which should be generically nonvanishing. We study an index analog of the microcanonical spectrum form factor in four-dimensional N=4 super Yang-Mills theory. In the large N limit and at large enough energy, the most dominant saddle corresponds to the black hole in the AdS bulk. This gives rise to the slope that decreases exponentially for a small imaginary chemical potential, which is a natural analog of an early time. We find that the "late-time" behavior is governed by the multicut saddles that arise in the index matrix model, which are nonperturbatively subdominant at early times. These saddles become dominant at late times, preventing the SFF from decaying. These multicut saddles correspond to the orbifolded Euclidean black holes in the AdS bulk, therefore giving the geometrical interpretation of the "ramp". Our analysis is done in the standard AdS/CFT setting without ensemble average or wormholes.

Emergent N=4 Supersymmetry from N=1.

We discover a four-dimensional N=1 supersymmetric field theory that is dual to the N=4 super Yang-Mills theory with gauge group SU(2n+1) for each n. The dual theory is constructed through the diagonal gauging of the SU(2n+1) flavor symmetry of three copies of a strongly coupled superconformal field theory (SCFT) of Argyres-Douglas type. We find that this theory flows in the infrared to a strongly coupled N=1 SCFT that lies on the same conformal manifold as N=4 super Yang-Mills with gauge group SU(2n+1). Our construction provides a hint on why certain N=1, 2 SCFTs have identical central charges (a=c).

Human cytomegalovirus induces and exploits Roquin to counteract the IRF1-mediated antiviral state.

RNA represents a pivotal component of host-pathogen interactions. Human cytomegalovirus (HCMV) infection causes extensive alteration in host RNA metabolism, but the functional relationship between the virus and cellular RNA processing remains largely unknown. Through loss-of-function screening, we show that HCMV requires multiple RNA-processing machineries for efficient viral lytic production. In particular, the cellular RNA-binding protein Roquin, whose expression is actively stimulated by HCMV, plays an essential role in inhibiting the innate immune response. Transcriptome profiling revealed Roquin-dependent global down-regulation of proinflammatory cytokines and antiviral genes in HCMV-infected cells. Furthermore, using cross-linking immunoprecipitation (CLIP)-sequencing (seq), we identified IFN regulatory factor 1 (IRF1), a master transcriptional activator of immune responses, as a Roquin target gene. Roquin reduces IRF1 expression by directly binding to its mRNA, thereby enabling suppression of a variety of antiviral genes. This study demonstrates how HCMV exploits host RNA-binding protein to prevent a cellular antiviral response and offers mechanistic insight into the potential development of CMV therapeutics.

Isolation of a Melanoblast Stimulator from Dimocarpus longan, Its Structural Modification, and Structure-Activity Relationships for Vitiligo.

A novel melanoblast stimulator (1) was isolated from Dimocarpus longan. Its analogs were also synthesized to support a new furan-based melanoblast stimulator scaffold for treating vitiligo. Isolated 5-(hydroxymethyl)furfural (HMF, 1) is a well-known compound in the food industry. Surprisingly, the melanogenic activity of HMF (1) was discovered here for the first time. Both HMF and its synthetic analog (16) promote the differentiation and migration of melanoblasts in vitro. Typically, stimulator (1) upregulated MMP2 expression, which promoted the migration of melanoblasts in vitro.

Wnt-Signaling Inhibitor Wnt-C59 Suppresses the Cytokine Upregulation in Multiple Organs of Lipopolysaccharide-Induced Endotoxemic Mice via Reducing the Interaction between ß-Catenin and NF-κB.

Sepsis is characterized by multiple-organ dysfunction caused by the dysregulated host response to infection. Until now, however, the role of the Wnt signaling has not been fully characterized in multiple organs during sepsis. This study assessed the suppressive effect of a Wnt signaling inhibitor, Wnt-C59, in the kidney, lung, and liver of lipopolysaccharide-induced endotoxemic mice, serving as an animal model of sepsis. We found that Wnt-C59 elevated the survival rate of these mice and decreased their plasma levels of proinflammatory cytokines and organ-damage biomarkers, such as BUN, ALT, and AST. The Wnt/ß-catenin and NF-κB pathways were stimulated and proinflammatory cytokines were upregulated in the kidney, lung, and liver of endotoxemic mice. Wnt-C59, as a Wnt signaling inhibitor, inhibited the Wnt/ß-catenin pathway, and its interaction with the NF-κB pathway, which resulted in the inhibition of NF-κB activity and proinflammatory cytokine expression. In multiple organs of endotoxemic mice, Wnt-C59 significantly reduced the ß-catenin level and interaction with NF-κB. Our findings suggest that the anti-endotoxemic effect of Wnt-C59 is mediated via reducing the interaction between ß-catenin and NF-κB, consequently suppressing the associated cytokine upregulation in multiple organs. Thus, Wnt-C59 may be useful for the suppression of the multiple-organ dysfunction during sepsis.

Life-Threatening Subglottic Stenosis of Granulomatosis with Polyangiitis: A Case Report.

Granulomatosis with polyangiitis (GPA) is an autoimmune disease characterized by necrotizing granulomatous inflammation. Subglottic stenosis, which is defined as narrowing of the airway below the vocal cords, has a frequency of 16-23% in GPA. Herein, we present the case of a 39-year-old woman with subglottic stenosis manifesting as life-threatening GPA, which was recurrent under systemic immunosuppressive therapy. The patient underwent an emergency tracheostomy, intratracheal intervention, such as carbon dioxide (CO2) laser surgery and intralesional steroid injection via laryngomicroscopic surgery, and laryngotracheal resection with remodeling. Severe subglottic stenosis treatment requires active intratracheal intervention, surgery, and systemic immunosuppressive therapy.

Wnt-C59 inhibits proinflammatory cytokine expression by reducing the interaction between ß-catenin and NF-κB in LPS-stimulated epithelial and macrophage cells.

Dysregulation of the Wnt pathway causes various diseases including cancer, Parkinson's disease, Alzheimer's disease, schizophrenia, osteoporosis, obesity and chronic kidney diseases. The modulation of dysregulated Wnt pathway is absolutely necessary. In the present study, we evaluated the anti-inflammatory effect and the mechanism of action of Wnt-C59, a Wnt signaling inhibitor, in lipopolysaccharide (LPS)-stimulated epithelial cells and macrophage cells. Wnt-C59 showed a dose-dependent anti-inflammatory effect by suppressing the expression of proinflammatory cytokines including IL6, CCL2, IL1A, IL1B, and TNF in LPS-stimulated cells. The dysregulation of the Wnt/ß-catenin pathway in LPS stimulated cells was suppressed by Wnt- C59 treatment. The level of ß-catenin, the executor protein of Wnt/ß-catenin pathway, was elevated by LPS and suppressed by Wnt-C59. Overexpression of ß-catenin rescued the suppressive effect of Wnt-C59 on proinflammatory cytokine expression and nuclear factor-kappa B (NF-κB) activity. We found that the interaction between ß-catenin and NF-κB, measured by co-immunoprecipitation assay, was elevated by LPS and suppressed by Wnt-C59 treatment. Both NF-κB activity for its target DNA binding and the reporter activity of NF-κB-responsive promoter showed identical patterns with the interaction between ß-catenin and NF-κB. Altogether, our findings suggest that the anti-inflammatory effect of Wnt-C59 is mediated by the reduction of the cellular level of ß-catenin and the interaction between ß-catenin and NF-κB, which results in the suppressions of the NF-κB activity and proinflammatory cytokine expression.

Landscape of Simple Superconformal Field Theories in 4D.

We explore the space of renormalization group flows that originate from supersymmetric N=1 SU(2) gauge theory with one adjoint and a pair of fundamental chiral multiplets. By considering all possible relevant deformations-including coupling to gauge-singlet chiral multiplets-we find 34 fixed points in this simple setup. We observe that theories in this class exhibit many novel phenomena: emergent symmetry, decoupling of operators, and narrow distribution of central charges a/c. This set of theories includes two of the N=2 minimal Argyres-Douglas theories and their mass deformed versions. In addition, we find 36 candidate fixed point theories possessing unphysical fermionic operators-including one with central charges (a,c)≃(0.20,0.22) that are smaller than any known superconformal theory-that need further investigation.

Enhancement of Supersymmetry via Renormalization Group Flow and the Superconformal Index.

We find a four-dimensional N=1 gauge theory which flows to the minimal interacting N=2 superconformal field theory, the Argyres-Douglas theory, in the infrared up to the extra free chiral multiplets. The gauge theory is obtained from a certain N=1 preserving deformation of the N=2 SU(2) gauge theory with four fundamental hypermultiplets. From this description, we compute the full superconformal index and find agreements with the known results in special limits.

Ultrathin Al2O3 interface achieving an 11.46% efficiency in planar n-Si/PEDOT:PSS hybrid solar cells.

Hybrid organic-inorganic photovoltaic devices consisting of poly(3,4-etyhlenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and n-type silicon have recently been investigated for their cost-efficiency and ease of fabrication. We demonstrate that the insertion of an ultrathin Al2O3 layer between n-Si and PEDOT:PSS significantly improves photovoltaic performance in comparison to the conventional interfacial oxide employing SiO2. A power-conversion efficiency of 11.46% was recorded at the optimal Al2O3 thickness of 2.3 nm. This result was achieved based upon increased built-in potential and improved charge collection via the electron blocking effect of Al2O3. In addition, the hydrophilicity enhanced by Al2O3 improved the coating uniformity of the PEDOT:PSS layer, resulting in a further reduction in surface recombination.

Planar n-Si/PEDOT:PSS hybrid heterojunction solar cells utilizing functionalized carbon nanoparticles synthesized via simple pyrolysis route.

Herein, we present a facile and simple strategy for in situ synthesis of functionalized carbon nanoparticles (CNPs) via direct pyrolysis of ethylenediaminetetraacetic acid (EDTA) on silicon surface. The CNPs were incorporated in hybrid planar n-Si and poly(3,4-etyhlenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) solar cells to improve device performance. We demonstrate that the CNPs-incorporated devices showed increased electrical conductivity (reduced series resistance) and minority carrier lifetime (better charge carrier collection) than those of the cells without CNPs due to the existence of electrically conductive sp 2-hybridized carbon at the heterojunction interfaces. With an optimal concentration of CNPs, the hybrid solar cells exhibited power conversion efficiency up to 11.95%, with an open-circuit voltage of 614 mV, short-circuit current density of 26.34 mA cm-2, and fill factor of 73.93%. These results indicate that our approach is promising for the development of highly efficient organic-inorganic hybrid solar cells.

Development of a Handheld Line Information Reader and Generator for Efficient Management of Optical Communication Lines.

A handheld line information reader and a line information generator were developed for the efficient management of optical communication lines. The line information reader consists of a photo diode, trans-impedance amplifier, voltage amplifier, microcontroller unit, display panel, and communication modules. The line information generator consists of a laser diode, laser driving circuits, microcontroller unit, and communication modules. The line information reader can detect the optical radiation field of the test line by bending the optical fiber. To enhance the sensitivity of the line information reader, an additional lens was used with a focal length of 4.51 mm. Moreover, the simulation results obtained through BeamPROP® software from Synopsys, Inc. demonstrated a stronger optical radiation field of the fiber due to a longer transmission wavelength and larger bending angle of the fiber. Therefore, the developed devices can be considered as useful tools for the efficient management of optical communication lines.

Toward a planar black silicon technology for 50 µm-thin crystalline silicon solar cells.

Auger and surface recombinations are major drawbacks that deteriorate a photon-to-electron conversion efficiencies in nanostructured (NS) Si solar cells. As an alternative to conventional frontside nanostructuring, we report how backside nanostructuring is beneficial for carrier collection during photovoltaic operation that utilizes a 50-µm-thin wafer. Ultrathin (4.3-nm-thin) zinc oxide was also effective for providing passivated tunneling contacts at the nanostructured backsides, which led to the enhancement of 24% in power conversion efficiency.

In vivo photoacoustic and fluorescence cystography using clinically relevant dual modal indocyanine green.

Conventional X-ray-based cystography uses radio-opaque materials, but this method uses harmful ionizing radiation and is not sensitive. In this study, we demonstrate nonionizing and noninvasive photoacoustic (PA) and fluorescence (FL) cystography using clinically relevant indocyanine green (ICG) in vivo. After transurethral injection of ICG into rats through a catheter, their bladders were photoacoustically and fluorescently visualized. A deeply positioned bladder below the skin surface (i.e., ~1.5-5 mm) was clearly visible in the PA and FL image using a laser pulse energy of less than 2 mJ/cm2 (1/15 of the safety limit). Then, the in vivo imaging results were validated through in situ studies. Our results suggest that dual modal cystography can provide a nonionizing and noninvasive imaging tool for bladder mapping.

Prevalence and risk factors for gallstone and renal stone formation in patients with intestinal Behçet's disease.

BACKGROUND/AIMS: The association between inflammatory bowel disease (IBD) and gallstone and renal stone formation has been established. However, few studies have investigated this association in patients with intestinal Behçet's disease (BD). We aimed to examine the prevalence of gallstones and renal stones in patients with intestinal BD and identify potential risk factors. METHODS: We analyzed gallstone and renal stone occurrences in 553 patients diagnosed with intestinal BD who had undergone cross-sectional imaging examinations between March 2005 and April 2021 at the IBD Center, Severance Hospital, Seoul, South Korea. Logistic regression models were used to identify risk factors for gallstone and renal stone formation. RESULTS: Of 553 patients over a mean 12.1-year duration, 141 (25.4%) patients had gallstones and 35 (6.3%) had renal stones. In multivariate logistic regression analysis, disease duration > 19 years (OR 2.91, 95% CI 1.56-5.44, 0.002). No significant correlation 0.001), prior intestinal BD-related surgery (OR 2.29, 95% CI 1.42-3.68, p < 0.001), and disease activity index for intestinal BD scores ≥ 75 (OR 2.23, 95% CI 1.12-4.45, p = 0.022) were associated with increased gallstone occurrence. A positive correlation was observed between renal stones, disease duration > 19 years (OR 5.61, 95% CI 1.98-15.90, p = 0.001) and frequent hospitalization (> 3 times) (OR 3.29, 95% CI 1.52-7.13, p = 0.002). No significant correlation was observed between gallstone and renal stone occurrence. CONCLUSION: These findings contribute to greater understanding concerning gallstone and renal stone prevalence and associated risk factors in patients with intestinal BD.

Erratum: A Study of the Reliability and Validity of the Korean Version of DSM-5 Symptom Measure-Inattention and Anger for Parent and Guardian of Child Age 6 to 17.

[This corrects the article on p. 71 in vol. 32, PMID: 33828406.].

Paeonia lactiflora extract improves the muscle function of mdx mice, an animal model of Duchenne muscular dystrophy, via downregulating the high mobility group box 1 protein.

ETHNOPHARMACOLOGICAL RELEVANCE: Paeonia lactiflora Pall. is an ethnopharmacological medicine with a long history of human use for treating various inflammatory diseases in many Asian countries. AIM OF THE STUDY: Duchenne muscular dystrophy (DMD) is an X-linked degenerative muscle disease affecting 1 in 3500 males and is characterized by severe muscle inflammation and a progressive decline in muscle function. This study aimed to elucidate the effects of an ethanol extract of the root of Paeonia lactiflora Pall. (PL) on the muscle function in the muscular dystrophy X-linked (mdx) mouse, the most commonly used animal model of DMD. MATERIALS AND METHODS: Male mdx mice and wild-type controls aged 5 weeks were orally treated with PL for 4 weeks. The corticosteroid prednisolone was used as a comparator drug. Muscle strength and motor coordination were assessed via the grip-strength and rotarod tests, respectively. Muscle damage was evaluated via histological examination and assessment of plasma creatine-kinase activity. Proteomic analyses were conducted to identify the muscle proteins whose levels were significantly affected by PL (ProteomeXchange identifier: PXD028886). Muscle and plasma levels of these proteins, and their corresponding mRNAs were measured using western blotting and ELISA, and quantitative reverse transcription-polymerase chain reaction, respectively. RESULTS: The muscle strength and motor coordination of mdx mice were significantly increased by the oral treatment of PL. PL significantly reduced the histological muscle damage and plasma creatine-kinase activity. Proteomic analyses of the muscle showed that PL significantly downregulated the high mobility group box 1 (HMGB1) protein and Toll-like receptor (TLR) 4, thus suppressing the HMGB1-TLR4-NF-κB signaling, in the muscle of mdx mice. Consequently, the muscle levels of proinflammatory cytokines/chemokines, which play crucial roles in inflammation, were downregulated. CONCLUSION: PL improves the muscle function and reduces the muscle damage in mdx mice via suppressing the HMGB1-TLR4-NF-κB signaling and downregulating proinflammatory cytokines/chemokines.

Tuft-cell-intrinsic and -extrinsic mediators of norovirus tropism regulate viral immunity.

Murine norovirus (MNoV) is a model for human norovirus and for interrogating mechanisms of viral tropism and persistence. We previously demonstrated that the persistent strain MNoVCR6 infects tuft cells, which are dispensable for the non-persistent strain MNoVCW3. We now show that diverse MNoV strains require tuft cells for chronic enteric infection. We also demonstrate that interferon-λ (IFN-λ) acts directly on tuft cells to cure chronic MNoVCR6 infection and that type I and III IFNs signal together via STAT1 in tuft cells to restrict MNoVCW3 tropism. We then develop an enteroid model and find that MNoVCR6 and MNoVCW3 similarly infect tuft cells with equal IFN susceptibility, suggesting that IFN derived from non-epithelial cells signals on tuft cells in trans to restrict MNoVCW3 tropism. Thus, tuft cell tropism enables MNoV persistence and is determined by tuft cell-intrinsic factors (viral receptor expression) and -extrinsic factors (immunomodulatory signaling by non-epithelial cells).

Functional and molecular dissection of HCMV long non-coding RNAs.

Small, compact genomes confer a selective advantage to viruses, yet human cytomegalovirus (HCMV) expresses the long non-coding RNAs (lncRNAs); RNA1.2, RNA2.7, RNA4.9, and RNA5.0. Little is known about the function of these lncRNAs in the virus life cycle. Here, we dissected the functional and molecular landscape of HCMV lncRNAs. We found that HCMV lncRNAs occupy ~ 30% and 50-60% of total and poly(A)+viral transcriptome, respectively, throughout virus life cycle. RNA1.2, RNA2.7, and RNA4.9, the three abundantly expressed lncRNAs, appear to be essential in all infection states. Among these three lncRNAs, depletion of RNA2.7 and RNA4.9 results in the greatest defect in maintaining latent reservoir and promoting lytic replication, respectively. Moreover, we delineated the global post-transcriptional nature of HCMV lncRNAs by nanopore direct RNA sequencing and interactome analysis. We revealed that the lncRNAs are modified with N6-methyladenosine (m6A) and interact with m6A readers in all infection states. In-depth analysis demonstrated that m6A machineries stabilize HCMV lncRNAs, which could account for the overwhelming abundance of viral lncRNAs. Our study lays the groundwork for understanding the viral lncRNA-mediated regulation of host-virus interaction throughout the HCMV life cycle.