Upper Respiratory Symptoms as Long COVID: Insight from a Multicenter Cohort Study.

Objective: This study aimed to investigate the clinical features of long COVID cases presenting with upper respiratory symptoms, a topic not yet fully elucidated. Study Design: Prospective cohort study. Setting: A multicenter study involving 26 medical facilities in Japan. Methods: Inclusion criteria were patients aged ≥18 years old with a confirmed COVID-19 diagnosis via severe acute respiratory syndrome coronavirus 2 polymerase chain reaction or antigen testing, who were hospitalized at the participating medical facilities. Analyzing clinical information and patient-reported outcomes from 1009 patients were analyzed. The outcome measured the degree of initial symptoms for taste or olfactory disorders and assessed the likelihood of these symptoms persisting as long COVID, as well as the impact on quality of life if the upper respiratory symptoms persisted as long COVID. Results: Patients with high albumin, low C-reactive protein, and low lactate dehydrogenase in laboratory tests tended to experience taste or olfactory disorders as part of long COVID. Those with severe initial symptoms had a higher risk of experiencing residual symptoms at 3 months, with an odds ratio of 2.933 (95% confidence interval [CI], 1.282-6.526) for taste disorders and 3.534 (95% CI, 1.382-9.009) for olfactory disorders. Presence of upper respiratory symptoms consistently resulted in lower quality of life scores. Conclusion: The findings from this cohort study suggest that severe taste or olfactory disorders as early COVID-19 symptoms correlate with an increased likelihood of persistent symptoms in those disorders as long COVID.

Extracellular aaRSs drive autoimmune and inflammatory responses in rheumatoid arthritis via the release of cytokines and PAD4.

OBJECTIVES: Recent studies demonstrate that extracellular-released aminoacyl-tRNA synthetases (aaRSs) play unique roles in immune responses and diseases. This study aimed to understand the role of extracellular aaRSs in the pathogenesis of rheumatoid arthritis (RA). METHODS: Primary macrophages and fibroblast-like synoviocytes were cultured with aaRSs. aaRS-induced cytokine production including IL-6 and TNF-α was detected by ELISA. Transcriptomic features of aaRS-stimulated macrophages were examined using RNA-sequencing. Serum and synovial fluid (SF) aaRS levels in patients with RA were assessed using ELISA. Peptidyl arginine deiminase (PAD) 4 release from macrophages stimulated with aaRSs was detected by ELISA. Citrullination of aaRSs by themselves was examined by immunoprecipitation and western blotting. Furthermore, aaRS inhibitory peptides were used for inhibition of arthritis in two mouse RA models, collagen-induced arthritis and collagen antibody-induced arthritis. RESULTS: All 20 aaRSs functioned as alarmin; they induced pro-inflammatory cytokines through the CD14-MD2-TLR4 axis. Stimulation of macrophages with aaRSs displayed persistent innate inflammatory responses. Serum and SF levels of many aaRSs increased in patients with RA compared with control subjects. Furthermore, aaRSs released PAD4 from living macrophages, leading to their citrullination. We demonstrate that aaRS inhibitory peptides suppress cytokine production and PAD4 release by aaRSs and alleviate arthritic symptoms in a mouse RA model. CONCLUSIONS: Our findings uncovered the significant role of aaRSs as a novel alarmin in RA pathogenesis, indicating that their blocking agents are potent antirheumatic drugs.

Clinical features of Japanese patients with gastrointestinal long-COVID symptoms.

Gastrointestinal (GI) long-COVID symptoms, including diarrhea and abdominal pain, have been reported in patients with long-COVID. However, the clinical features of patients with GI long-COVID symptoms remain unclear. We conducted a large-scale prospective cohort study focusing on the clinical characteristics of patients with GI long-COVID symptoms in Japan. Among 943 COVID-19 patients, 58 patients (6.2%) had GI long-COVID symptoms. The health-related quality of life (QOL) parameters (the Short Form-8 [SF-8] and Euro Quality of Life 5 Dimensions 5 level [EQ-5D-5L]) at 12 months after diagnosis in patients with GI long-COVID symptoms were significantly lower than in those without GI long-COVID symptoms (P < 0.0001). Moreover, patients with GI long-COVID symptoms had more varied long-COVID symptoms compared to patients without GI long-COVID symptoms.

Search for the Decomposition Process of 2,4,6-Trinitrotoluene by an Evolutionary Algorithm.

In this paper, we explored stable states in the system of 2,4,6-trinitrotoluene (TNT) crystal with a few additional hydrogen radicals (Hadd's) using a structure-search scheme based on first-principles calculations and an evolutionary algorithm (EA) to get insights into the decomposition process of TNT. We introduced three evolutionary operators acting on Hadd's and transforming only local structures of TNT molecules: "displacement", "permutation", and "mating". We searched for stable structures by increasing the number of Hadd's (n) from 1 to 2, 3, 4, 6, and 8 and constructed a convex-hull diagram for the formation energy from solid TNT and solid hydrogen. We showed that the system of n = 6 had the largest energy reduction, in which five of the eight TNT molecules in the calculation cell were transformed into NO, H2O, C2H3N, C2NO3H3, C8N2O4H7, C9N2O8H5, and C14N7O12H11. Analysis of the structural transformations observed during the EA search indicates that (1) the Hadd's approaching the TNT molecules react with C, forming a six-membered ring, and with N and O in nitro groups, leaving the TNT molecules as NO, H2O, C2H3N, and C2NO3H3, and (2) the partially decomposed TNT molecules are bonded to one another via C, N, and O.

Application of Magnetic Nanoparticles for Rapid Detection and In Situ Diagnosis in Clinical Oncology.

Screening, monitoring, and diagnosis are critical in oncology treatment. However, there are limitations with the current clinical methods, notably the time, cost, and special facilities required for radioisotope-based methods. An alternative approach, which uses magnetic beads, offers faster analyses with safer materials over a wide range of oncological applications. Magnetic beads have been used to detect extracellular vesicles (EVs) in the serum of pancreatic cancer patients with statistically different EV levels in preoperative, postoperative, and negative control samples. By incorporating fluorescence, magnetic beads have been used to quantitatively measure prostate-specific antigen (PSA), a prostate cancer biomarker, which is sensitive enough even at levels found in healthy patients. Immunostaining has also been incorporated with magnetic beads and compared with conventional immunohistochemical methods to detect lesions; the results suggest that immunostained magnetic beads could be used for pathological diagnosis during surgery. Furthermore, magnetic nanoparticles, such as superparamagnetic iron oxide nanoparticles (SPIONs), can detect sentinel lymph nodes in breast cancer in a clinical setting, as well as those in gallbladder cancer in animal models, in a surgery-applicable timeframe. Ultimately, recent research into the applications of magnetic beads in oncology suggests that the screening, monitoring, and diagnosis of cancers could be improved and made more accessible through the adoption of this technology.

Adenine nucleotide translocase 2, a putative target protein for 2-carba cyclic phosphatidic acid in microglial cells.

Lipid-protein interactions play essential roles in many biological phenomena. Lysophospholipid mediators, such as cyclic phosphatidic acid (cPA), have been recognized as secondary messengers, yet few cellular targets for cPA have been identified to date. Furthermore, the molecular mechanism that activates these downstream signaling events remains unknown. In this study, using metabolically stabilized cPA carba-derivative (2ccPA)-immobilized magnetic beads, we identified adenine nucleotide translocase 2 (ANT2) as a 2ccPA-interacting protein in microglial cells. 2ccPA was tested for its ability to inhibit apoptosis caused by phenylarsine oxide in microglial cells. This damage was significantly improved upon 2ccPA treatment, along with cell proliferation, apoptosis, reactive oxygen species production, and intracellular ATP levels. This is the first report to suggest the direct binding of 2ccPA to ANT2 in microglial cells and provides evidence for a new benefit of 2ccPA in protecting microglial cells from apoptotic death induced by the ANT2-mediated signaling pathway.

A case report, a case who developed limited cutaneous scleroderma and pulmonary hypertension 8 years after diagnosis of anti-centromere antibody-positive Sjögren syndrome.

A 52-year-old woman was diagnosed as having anti-centromere antibody (ACA)-positive primary Sjögren syndrome (pSS). Eight years later, she visited our hospital because she had developed dyspnoea. She was diagnosed as having pulmonary arterial hypertension (PAH) with pulmonary veno-occlusive disease on the basis of the results of right heart catheterisation, a severe decrease in diffusing capacity of the lung for carbon monoxide (DLCO, 17%) and desaturation (69%) after a 6-minute walk test. She was also diagnosed as having limited cutaneous systemic sclerosis (lcSSc) because she had developed finger sclerosis. The six-minute walk distance had improved by 54 m 3 months after commencing treatment with tadalafil. Clinicians should be alert to the possibility of patients with ACA-positive SS developing lcSSc and PAH during their clinical course.

UGGT1 retains proinsulin in the endoplasmic reticulum in an arginine dependent manner.

We sought to clarify a pathway by which L- and dD-arginine simulate insulin secretion in mice and cell lines and obtained the following novel two findings. (1) Using affinity magnetic nanobeads technology, we identified that proinsulin is retained in the endoplasmic reticulum (ER) through UDP-glucose:glycoprotein glucosyltransferase 1 (UGGT1) when arginine availability is limited. (2) L- and d-arginine release proinsulin from UGGT1 through competition with proinsulin and promote exit of proinsulin from the ER to Golgi apparatus. The ability of arginine to release proinsulin from UGGT1 closely correlates with arginine-induced insulin secretion in several models of ß cells indicating that UGGT1-proinsulin interaction regulates arginine-induced insulin secretion.

A Case of Autoimmune Pulmonary Alveolar Proteinosis with Pulmonary Fibrosis and Asbestosis-Like Features.

A 78-year-old man who had worked in the building industry visited our hospital because of groundglass opacity with smoothly thickened, intralobular interstitial lines and interlobular septal lines on chest high-resolution computed tomography (HRCT). HRCT image also showed a focal area of reticulation and pleural thickening. Lung specimens obtained by surgical lung biopsy showed accumulations of intra-alveolar periodic acid-Schiffpositive materials, usual interstitial pneumonia (UIP)-like subpleural lung fibrosis and asbestos bodies (1 body/cm2 in high-power field, ×400). Serum granulocyte-macrophage colony stimulating factor autoantibody was positive. The patient was diagnosed as having autoimmune pulmonary alveolar proteinosis (PAP) and needed differential diagnosis from secondary PAP caused from pulmonary asbestosis and UIP. Careful observation of the manifestations of pulmonary asbestosis and the progression of fibrosis using HRCT will be necessary in this patient.

Genome-wide screening reveals a role for subcellular localization of CRBN in the anti-myeloma activity of pomalidomide.

Pomalidomide, a derivative of thalidomide, is an effective treatment for multiple myeloma. The drug exerts its effects through CRBN, a component of the E3 ubiquitin ligase complex CRL4CRBN. To search for novel factors involved in the anti-cancer activity of pomalidomide, we performed a genome-wide shRNA library screen and identified 445 genes as those affecting pomalidomide sensitivity. Genes encoding components of the ubiquitin-proteasome pathway, such as subunits of the CRL4CRBN complex, the COP9 signalosome, and the 26S proteasome, were among the pomalidomide-affecting genes. Karyopherin beta 1 (KPNB1) was identified as a novel pomalidomide-affecting gene. KPNB1 was required for the nuclear import of CRBN and for the CRBN-directed, pomalidomide-dependent degradation of a clinically relevant substrate, the transcription factor Aiolos. By contrast, the cytoplasmic translation factor GSPT1 was degraded following treatment with the thalidomide derivative CC-885 only when CRBN was present in the cytoplasm, indicating that subcellular distribution of CRBN is critical for the efficacy of thalidomide-based medications.

Cereblon Control of Zebrafish Brain Size by Regulation of Neural Stem Cell Proliferation.

Thalidomide is a teratogen that causes multiple malformations in the developing baby through its interaction with cereblon (CRBN), a substrate receptor subunit of the CRL4 E3 ubiquitin ligase complex. CRBN was originally reported as a gene associated with autosomal recessive non-syndromic mild mental retardation. However, the function of CRBN during brain development remains largely unknown. Here we demonstrate that CRBN promotes brain development by facilitating the proliferation of neural stem cells (NSCs). Knockdown of CRBN in zebrafish embryos impaired brain development and led to small brains, as did treatment with thalidomide. By contrast, overexpression of CRBN resulted in enlarged brains, leading to the expansion of NSC regions and increased cell proliferation in the early brain field and an expanded expression of brain region-specific genes and neural and glial marker genes. These results demonstrate that CRBN functions in the determination of brain size by regulating the proliferation of NSCs during development.

Magnetically Promoted Rapid Immunofluorescence Staining for Frozen Tissue Sections.

Current immunohistochemistry methods for diagnosing abnormal cells, such as cancer cells, require multiple steps and can be relatively slow compared with intraoperative frozen hematoxylin and eosin staining, and are therefore rarely used for intraoperative examination. Thus, there is a need for novel rapid detection methods. We previously demonstrated that functionalized fluorescent ferrite beads (FF beads) magnetically promoted rapid immunoreactions. The aim of this study was to improve the magnetically promoted rapid immunoreaction method using antibody-coated FF beads and a magnet subjected to a magnetic field. Using frozen sections of xenograft samples of A431 human epidermoid cancer cells that express high levels of epidermal growth factor receptor (EGFR) and anti-EGFR antibody-coated FF beads, we reduced the magnetically promoted immunohistochemistry procedure to a 1-min reaction and 1-min wash. We also determined the optimum magnetic force for the antibody reaction (from 7.79 × 10-15 N to 3.35 × 10-15 N) and washing (4.78 × 10-16 N), which are important steps in this technique. Furthermore, we stained paraffin-embedded tissue arrays and frozen sections of metastatic breast cancer lymph nodes with anti-pan-cytokeratin antibody-coated FF beads to validate the utility of this system in clinical specimens. Under optimal conditions, this ultra-rapid immunostaining method may provide an ancillary method for pathological diagnosis during surgery. (J Histochem Cytochem 58:XXX-XXX, 2010).

Application of high-performance magnetic nanobeads to biological sensing devices.

Nanomaterials have extensive applications in the life sciences and in clinical diagnosis. We have developed magnetic nanoparticles with high dispersibility and extremely low nonspecific binding to biomolecules and have demonstrated their application in chemical biology (e.g., for the screening of drug receptor proteins). Recently, the excellent properties of nanobeads have made possible the development of novel rapid immunoassay systems and high-precision technologies for exosome detection. For immunoassays, we developed a technology to encapsulate a fluorescent substance in magnetic nanobeads. The fluorescent nanobeads allow the rapid detection of a specific antigen in solution or in tissue specimens. Exosomes, which are released into the blood, are expected to become markers for several diseases, including cancer, but techniques for measuring the absolute quantity of exosomes in biological fluids are lacking. By integrating magnetic nanobead technology with an optical disc system, we developed a novel method for precisely quantifying exosomes in human serum with high sensitivity and high linearity without requiring enrichment procedures. This review focuses on the properties of our magnetic nanobeads, the development of novel biosensors using these nanobeads, and their broad practical applications. Graphical abstract ᅟ.

Low positive titer of anti-melanoma differentiation-associated gene 5 antibody is not associated with a poor long-term outcome of interstitial lung disease in patients with dermatomyositis.

BACKGROUND: Anti-melanoma differentiation-associated gene 5 antibody (anti-MDA5-Ab) is associated with fatal rapidly progressive interstitial lung disease (RP-ILD) in patients with dermatomyositis (DM). We attempted to clarify whether anti-MDA5-Ab is associated with long-term outcomes in patients with DM-ILD. METHODS: Thirty-six patients with DM-ILD were retrospectively analyzed for their serum anti-MDA5-Ab by using an enzyme-linked immunosorbent assay. We analyzed the association between clinical parameters, including the serum levels of anti-MDA5-Ab and ferritin. RESULTS: Fourteen patients (39%) were positive for anti-MDA5-Ab. The serum levels of anti-MDA5-Ab and ferritin in 7 patients with acute death were higher than those in the surviving patients. An "unclassifiable pattern" on chest computed tomography and the development of RP-ILD were also prognostic markers. The serum levels of anti-MDA5-Ab and ferritin (cut-off levels, 100 IU/mL and 899 ng/mL, respectively) were markers predictive of acute death, showing good sensitivity (86% and 83%) and specificity (97% and 100%). All 7 patients with acute death developed RP-ILD and were positive for anti-MDA5-Ab, including 6 patients with a high titer (≥100 IU/mL), whereas only 2 patients (29%) developed RP-ILD among the 7 survivors with a low titer of anti-MDA5-Ab ( < 100 IU/mL). In contrast, a low positive titer of anti-MDA5-Ab was not associated with changes in pulmonary function for 2 years. CONCLUSIONS: Although a high serum titer of anti-MDA5-Ab (≥100 IU/mL) is associated with acute death via the development of RP-ILD, outcomes in the chronic phase for patients with a low titer of anti-MDA5-Ab ( < 100 IU/mL) were similar to those of patients without anti-MDA5-Ab.

Development of a Highly Sensitive Device for Counting the Number of Disease-Specific Exosomes in Human Sera.

BACKGROUND: Although circulating exosomes in blood play crucial roles in cancer development and progression, difficulties in quantifying exosomes hamper their application for reliable clinical testing. By combining the properties of nanobeads with optical disc technology, we have developed a novel device named the ExoCounter to determine the exact number of exosomes in the sera of patients with various types of cancer. METHOD: In this system, individual exosomes were captured in the groove of an optical disc coated with antibodies against exosome surface antigens. The captured exosomes were labeled with antibody-conjugated magnetic nanobeads, and the number of the labeled exosomes was counted with an optical disc drive. RESULTS: We showed that the ExoCounter could detect specific exosomes derived from cells or human serum without any enrichment procedures. The detection sensitivity and linearity with this system were higher than those with conventional detection methods such as ELISA or flow cytometry. In addition to the ubiquitous exosome markers CD9 and CD63, the cancer-related antigens CD147, carcinoembryonic antigen, and human epidermal growth factor receptor 2 (HER2) were also used to quantify cancer cell line-derived exosomes. Furthermore, analyses of a cross-sectional cohort of sera samples revealed that HER2-positive exosomes were significantly increased in patients with breast cancer or ovarian cancer compared with healthy individuals and those with noncancer diseases. CONCLUSIONS: The ExoCounter system exhibits high performance in the direct detection of exosomes in cell culture and human sera. This method may enable reliable analysis of liquid biopsies.

Structural basis of thalidomide enantiomer binding to cereblon.

Thalidomide possesses two optical isomers which have been reported to exhibit different pharmacological and toxicological activities. However, the precise mechanism by which the two isomers exert their different activities remains poorly understood. Here, we present structural and biochemical studies of (S)- and (R)-enantiomers bound to the primary target of thalidomide, cereblon (CRBN). Our biochemical studies employed deuterium-substituted thalidomides to suppress optical isomer conversion, and established that the (S)-enantiomer exhibited ~10-fold stronger binding to CRBN and inhibition of self-ubiquitylation compared to the (R)-enantiomer. The crystal structures of the thalidomide-binding domain of CRBN bound to each enantiomer show that both enantiomers bind the tri-Trp pocket, although the bound form of the (S)-enantiomer exhibited a more relaxed glutarimide ring conformation. The (S)-enantiomer induced greater teratogenic effects on fins of zebrafish compared to the (R)-enantiomer. This study has established a mechanism by which thalidomide exerts its effects in a stereospecific manner at the atomic level.

Successful Treatment of Rapidly Progressive Unclassifiable Idiopathic Interstitial Pneumonia with Anti-melanoma Differentiation-associated Gene-5 Antibody by Intensive Immunosuppressive Therapy.

We describe a case of a woman who presented with a persistent cough, general fatigue, and a fever. Interstitial lung disease was rapidly progressive and resistant to high-dose steroid therapy. She tested positive for the presence of anti-melanoma differentiation-associated gene 5 (MDA-5) antibody, although she had no skin manifestations of dermatomyositis. She was eventually diagnosed with unclassifiable idiopathic interstitial pneumonia and was successfully treated with intensive immunosuppressive therapy including intravenous cyclophosphamide. To our knowledge, this is the first report of anti-MDA-5 antibody in a patient with idiopathic interstitial pneumonia.

Esthetic abutment design for angulated screw channels: A technical report.

Angulated screw channel system abutments (ASCs) have recently been introduced to address the problem with visible screw access that may compromise esthetics. ASCs allow the screw access to be modified up to 25 degrees relative to the implant axis. However, a widened channel, which may cause thinning of the facial ceramic, is needed at the implant screw head to allow for proper engagement of the screwdriver. This technical report introduces a custom titanium insert design, the Satoshi Sakamoto (SS) abutment. The SS abutment consists of a custom titanium metal insert and zirconia coping in which the access hole is located in an esthetic position with an ASC system. The SS abutment results in a crown with more normal crown dimensions that also provides more space for the soft tissues. This SS abutment design allows clinicians to obtain screw-retained restorations with optimal esthetics and mechanical strength.

Dental Technicians' Pneumoconiosis.

A 40-year-old female dental technician visited our hospital for the investigation of a chest X-ray abnormality. Chest computed tomography demonstrated centrilobular nodules and lung volume reduction, and her serum KL-6 level was elevated. A histological analysis of the specimens obtained on a surgical lung biopsy showed peribronchiolar fibrosis with pigmented macrophages and cholesterol clefts. An energy-dispersive X-ray analysis showed that these lung tissues contained some metals, including indium. The serum indium level was also elevated. We diagnosed this patient with pneumoconiosis caused by exposure to sandblasting certain dental metals. This is the first reported case of pneumoconiosis in a dental technician associated with exposure to indium.

The Neuroprotective Marine Compound Psammaplysene A Binds the RNA-Binding Protein HNRNPK.

In previous work, we characterized the strong neuroprotective properties of the marine compound Psammaplysene A (PA) in in vitro and in vivo models of neurodegeneration. Based on its strong neuroprotective activity, the current work attempts to identify the physical target of PA to gain mechanistic insight into its molecular action. Two distinct methods, used in parallel, to purify protein-binding partners of PA led to the identification of HNRNPK as a direct target of PA. Based on surface plasmon resonance, we find that the binding of PA to HNRNPK is RNA-dependent. These findings suggest a role for HNRNPK-dependent processes in neurodegeneration/neuroprotection, and warrant further study of HNRNPK in this context.