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Background Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne disease caused by Bandavirus dabieense (SFTS virus [SFTSV]). Recently, at least 6 different genotypes of SFTSV have been identified, with genotypes A, D, and F dominant in China and B dominant in Japan and Korea. This study investigated the effect of SFTSV genotypes circulating in South Korea on disease severity, viral load, and cytokine profile. Methods We prospectively enrolled 70 patients with SFTS from July 2015 to June 2022. Serial plasma samples were obtained during hospitalization and analyzed. Viral load was measured by real-time reverse-transcription polymerase chain reaction. Partial sequences of the viral genome were analyzed for genotyping. Plasma concentrations of 17 cytokines were measured by multiplex-bead immunoassay. Results Of 70 samples, 51 could be genotyped. Genotype B was predominant (80.4%) and other genotypes were uncommon. Intensive care unit admission rates (51.2% vs 50.0%) and mortality rates (26.8% vs 40.0%) did not show any significant differences between genotype B and non-B genotypes. The initial viral load did not show any significant differences (3.59 vs 3.64 log copies/μL), whereas viral load measured at hospital day 3–4 tended to be higher in genotype B than non-B genotypes (3.83 vs 1.83 log copies/μL, P =.07). Additionally, the plasma concentrations of interferon-α, interleukin 10, and interferon-γ–induced protein 10, which are closely related to mortality in cases of SFTS, did not show any significant differences. Conclusions SFTSV genotype B was the prevalent genotype in South Korea, with no genotype-specific difference in clinical outcomes, initial viral load, or cytokine profiles. [ABSTRACT FROM AUTHOR]

Our calculations of ferromagnetic spin chains on s-wave superconductors show that the energy oscillations of edge states with the chain's length are due to a moiré pattern emerging from the electronic interactions in the superconductor and the discreteness of the spin-chain lattice. By modifying the spin lattice, the moiré dispersion of edge states can be controlled. In particular, we can engineer nondispersive edge states that remain at fixed energy regardless of the size distribution of the spin chains. This is an important step in the study of edge states of spin chains that can be fabricated with a certain size dispersion.

Immunocompromised patients with coronavirus disease 2019 were prospectively enrolled from March to November 2022 to understand the association between antibody responses and severe acute respiratory syndrome coronavirus 2 shedding. A total of 62 patients were analyzed, and the results indicated a faster decline in genomic and subgenomic viral RNA in patients with higher neutralizing and S1-specific immunoglobulin G (IgG) antibodies (both P <.001). Notably, high neutralizing antibody levels were associated with a significantly faster decrease in viable virus cultures (P =.04). Our observations suggest the role of neutralizing antibodies in prolonged virus shedding in immunocompromised patients, highlighting the potential benefits of enhancing their humoral immune response through vaccination or monoclonal antibody treatments. [ABSTRACT FROM AUTHOR]

π-magnetism in graphene systems has been predicted but remains an experimental challenge. Here the authors report the discovery of unpaired electron spins localized in certain sites of graphene nanoribbons, and the measurement of their coupling by inducing singlet-triplet excitations with a scanning tunneling microscope.

Understanding the magnetic properties of molecules at the atomic level is a crucial aspect in the growing area of organic spintronics. This study brings further insight into the mechanisms of electron-spin interactions by investigating an iron-based organic molecule deposited on gold substrates.

The letter to the editor discusses a study conducted in South Korea that examined the immune response to COVID-19 in healthcare workers. The study found that individuals with hybrid immunity, meaning they had both natural infection and vaccination, and higher levels of certain antibodies had a lower risk of subsequent infection. The study suggests that these antibody levels can be used as an indicator of protection against infection. However, baseline saliva IgA antibodies did not show a protective role. The study concludes that further research is needed to fully understand the mechanisms involved. [Extracted from the article]

There are limited data supporting current Centers for Disease Control and Prevention guidelines for the isolation period in moderate to severely immunocompromised patients with coronavirus disease 2019 (COVID‐19). Adult COVID‐19 patients who underwent solid organ transplantation (SOT) or received active chemotherapy against hematologic malignancy were enrolled and weekly respiratory samples were collected. Samples with positive genomic real‐time polymerase chain reaction results underwent virus culture and rapid antigen testing (RAT). A total of 65 patients (40 with hematologic malignancy and 25 SOT) were enrolled. The median duration of viable virus shedding was 4 weeks (interquartile range: 3–7). Multivariable analysis revealed that B‐cell depletion (hazard ratio [HR]: 4.76) was associated with prolonged viral shedding, and COVID‐19 vaccination (≥3 doses) was negatively associated with prolonged viral shedding (HR: 0.22). The sensitivity, specificity, positive predictive value, and negative predictive value of RAT for viable virus shedding were 79%, 76%, 74%, and 81%, respectively. The negative predictive value of RAT was only 48% (95% confidence interval [CI]: 33–65) in the samples from those with symptom onset ≤20 days, but it was as high as 92% (95% CI: 85–96) in the samples from those with symptom onset >20 days. About half of immunocompromised COVID‐19 patients shed viable virus for ≥4 weeks from the diagnosis, and virus shedding was prolonged especially in unvaccinated patients with B‐cell‐depleting therapy treatment. RAT beyond 20 days in immunocompromised patients had a relatively high negative predictive value for viable virus shedding. [ABSTRACT FROM AUTHOR]

This article explores the use of whole genome sequencing (WGS) to analyze the mutations of the SARS-CoV-2 virus in immunocompromised patients with persistent viral detection. The study, conducted at a tertiary teaching hospital, included 13 patients and found that each patient had unique and different mutations distributed throughout the entire SARS-CoV-2 genome. These findings suggest that immunocompromised patients may contribute to the emergence of new variants. The study focused on mutations during the Omicron era and found that patients acquired a median of two amino acid substitutions over a median of 51 days, with most mutations occurring in specific regions of the genome. Some mutations were associated with immune evasion, remdesivir resistance, and the emergence of new variants. The study suggests that immunocompromised individuals with persistent viral detection should be cautious about ending isolation, but the results may not apply to all immunocompromised populations due to limitations in the study. [Extracted from the article]

The complex internal structure of magnetic impurities, which locally distort superconductivity, is usually neglected. Here, Choiet al. report that the number and shape of Shiba states are correlated to the spin-polarized atomic orbitals of the impurity, valuable to design atomic-scale superconducting devices.

Clinical value of mitochondrial DNA has been described in colorectal cancer (CRC). To clarify its role in colorectal carcinogenesis, mitochondrial microsatellite instability (mtMSI) and other markers were investigated in CRCs and their precancerous lesions, as a multitier genetic study. DNA was isolated from paired normal and tumoral tissues in 78 tubular adenomas (TAs), 34 serrated polyps (SPs), and 100 CRCs. mtMSI, nucleus microsatellite instability (nMSI), KRAS mutation, and BRAF mutation were investigated in these tumors and their statistical analysis was performed. mtMSI was found in 30% of CRCs and 21.4% of precancerous lesions. Mitochondrial copy number was higher in SPs than TAs and it was associated with mtMSI in low grade TAs. KRAS and BRAF mutations were mutually exclusive in TAs and SPs. CRCs with mtMSI showed shorter overall survival times than the patients without mtMSI. In CRCs without nMSI or BRAF mutation, mtMSI was a more accurate marker for predicting prognosis. The genetic change of mitochondrial DNA is an early and independent event in colorectal precancerous lesions and mtMSI and mitochondrial contents are associated with the tubular adenoma-carcinoma sequence, resulting in poor prognosis. This result suggested that the genetic change in mitochondrial DNA appears to be a possible prognosis marker in CRC.

• Immunocompromised patients with COVID-19 shed viable virus for median 4 weeks. • B-cell depleting therapy increases the risk of prolonged viable viral shedding. • Vaccination shortens the viable virus shedding in immunocompromised patients. [ABSTRACT FROM AUTHOR]

Alow-temperature scanning tunneling microscopewas employed to study the differential conductance in an atomic junction formed by an adsorbed Co atom on a Cu(100) surface and a copper-covered tip.A zero-bias anomaly (ZBA) reveals spin scattering off the Co atom, which is assigned to a Kondo effect. The ZBA exhibits a characteristic asymmetric lineshape when electrons tunnel between tip and sample, while upon the tip-Co contact it symmetrizes and broadens. Through density functional theory calculations and the non-equilibrium non-crossing approximation, we showthat the lineshape broadening is mainly a consequence of the additional coupling to the tip, while non-equilibrium effects only modify the large-bias tails of the ZBA. [ABSTRACT FROM AUTHOR]

The creation of molecule-like structures in which magnetic atoms interact controllably is full of potential for the study of complex or strongly correlated systems. Here, we create spin chains in which a strongly correlated Kondo state emerges from magnetic coupling of transition-metal atoms. We build chains up to ten atoms in length by placing Fe and Mn atoms on a Cu2N surface with a scanning tunneling microscope. The atoms couple antiferromagnetically via superexchange interaction through the nitrogen atom network of the surface. The emergent Kondo resonance is spatially distributed along the chain. Its strength can be controlled by mixing atoms of different transition metal elements and manipulating their spatial distribution. We show that the Kondo screening of the full chain by the electrons of the nonmagnetic substrate depends on the interatomic entanglement of the spins in the chain, demonstrating the prerequisites to build and probe spatially extended strongly correlated nanostructures. [ABSTRACT FROM AUTHOR]

Mutations in the promoter region of telomerase reverse transcriptase (TERT) and alterations in telomere length (TL) have been the focus of research in various types of cancer. In the present study, the frequency and clinical characteristics of TERT promoter mutations and TL were studied in non-small cell lung cancers (NSCLC). TERT promoter mutations and TL were analyzed in 188 patients using DNA sequencing and the reverse transcription-quantitative polymerase chain reaction, respectively. The TERT promoter mutation rate was observed to be 2.2% (4/188 NSCLC cases), and it was significantly associated with regional lymph node invasion (P<0.001). No significant difference in TL was observed between the patients with and without TERT promoter mutations. TL was decreased in males (P=0.058 vs. females) and smokers (P=0.008 vs. non-smokers). Survival analyses demonstrated poor prognoses for patients with NSCLC with TERT promoter mutations (P<0.001). Multivariate survival analyses demonstrated that TERT promoter mutations were an independent prognostic marker for poor overall survival (P=0.045). The results of the present study demonstrated that TERT promoter mutation was not frequent in NSCLC; however, it may have value as a prognostic marker in NSCLC. [ABSTRACT FROM AUTHOR]

Magnetic anisotropy plays a key role in the magnetic stability and spin-related quantum phenomena of surface adatoms. It manifests as angular variations of the atom's magnetic properties. We measure the spin excitations of individual Fe atoms on a copper nitride surface with inelastic electron tunneling spectroscopy. Using a three-axis vector magnet we rotate the magnetic field and map out the resulting variations of the spin excitations. We quantitatively determine the three-dimensional distribution of the magnetic anisotropy of single Fe atoms by fitting the spin excitation spectra with a spin Hamiltonian. This experiment demonstrates the feasibility of fully mapping the vector magnetic properties of individual spins and characterizing complex three-dimensional magnetic systems. [ABSTRACT FROM AUTHOR]

The purpose of this study was to report variations of the cubital superficial vein patterns in the Korean subjects, which was investigated by using venous illuminator, AccuVein. The 200 Korean subjects were randomly chosen from the patients and staff of the Keimyung University Dongsan Medical Center in Daegu, Korea. After excluding the inappropriate cases for detecting venous pattern, we collected 174 cases of right upper limbs and 179 cases of left upper limbs. The superficial veins of the cubital fossa were detected and classified into four types according to the presence of the median cubital vein (MCV) or median antebrachial vein. The type II, presenting the both cephalic and basilic vein connected by the MCV, was most common (177 upper limbs, 50.1%). Although the most common type in male and female was different as type I (108 upper limbs, 49.3%) and type II (75 upper limbs, 56.0%), respectively, statistical significance was not detected (P=0.241). The frequency of the each types between right and left upper limbs was also not different (P=0.973). Among 154 subjects who were observed the venous pattern in the both upper limbs, 76 subjects (49.3%) had the same venous pattern. Using AccuVein to investigate the venous pattern has an advantage of lager scale examination compared to the cadaver study. Our results might be helpful for medical practitioner to be aware of the variation of the superficial cubital superficial vein. [ABSTRACT FROM AUTHOR]

Continuous attention has been developed on the anatomical variations of the axilla in anatomist and surgeon due to their clinical importance. The axillary region is an anatomical space between the lateral part of the chest wall and the medial aspect of the upper limb. During the routine dissection of embalmed cadavers, we found variant muscular slip originating from the lateral border of tendinous part of the latissimus dorsi and continuing 9 cm more crossing the axilla. And then, it inserted into the superior margin of the insertion of the pectoralis major. We considered this muscular variation as axillary arch muscle. Correct identification of the relevant anatomy and subsequent simple surgical division is curative, paying special attention to anatomical variations in this region and its clinical importance due to its close relationship to the neurovascular elements of the axilla. [ABSTRACT FROM AUTHOR]

Optimization of submerged culture conditions for the production of mycelial growth and exopolysaccharides (EPSs) by Collybia maculata was investigated. The optimum temperature and the initial pH for EPS production in a shake-flask culture of C. maculata were found to be 20C and 5.5, respectively. Among the various medium's constituents examined, glucose, Martone A-1, K2HPO4, and CaCl2 were the most suitable carbon, nitrogen, and mineral sources for EPS production, respectively. The optimum concentration of the medium's ingredients determined using the orthogonal matrix method was as follows: 30 g/L of glucose, 20 g/L of Martone A-1, 1 g/L of K2HPO4, and 1 g/L of CaCl2. Under the optimized culture conditions, the maximum concentration of EPSs in a 5-L stirred-tank reactor was 2.4 g/L, which was approximately five times higher than that in the basal medium. A comparative fermentation result showed that the EPS productivity in an airlift reactor was higher than that in the stirred-tank reactor despite the lower mycelial growth rate. The specific productivities and the yield coefficients in the airlift reactor were higher than those in the stirred-tank reactor even though the volumetric productivities were higher in the stirred-tank reactor than in the airlift reactor. [ABSTRACT FROM AUTHOR]

We show that the magnetic ordering of coupled atomic dimers on a superconductor is revealed by their intragap spectral features. Chromium atoms on the superconductor β-Bi2Pd surface display Yu-Shiba-Rusinov bound states, detected as pairs of intragap excitations in tunneling spectra. By means of atomic manipulation with a scanning tunneling microscope's tip, we form Cr dimers with different arrangements and find that their intragap features appear either shifted or split with respect to single atoms. These spectral variations are associated with the magnetic coupling, ferromagnetic or antiferromagnetic, of the dimer, as confirmed by density functional theory simulations. The striking qualitative differences between the observed tunneling spectra prove that intragap Shiba states are extremely sensitive to the magnetic ordering on the atomic scale. [ABSTRACT FROM AUTHOR]

Heterogeneous atomic magnetic chains are built by atom manipulation on a Cu2N/Cu (100) substrate. Their magnetic properties are studied and rationalized by a combined scanning tunneling microscopy (STM) and density functional theory (DFT) work completed by model Hamiltonian studies. The chains are built using Fe and Mn atoms ontop of the Cu atoms along the N rows of the Cu2N surface. Here, we present results for FeMnx chains (x=1-6) emphasizing the evolution of the geometrical, electronic, and magnetic properties with chain size. By fitting our results to a Heisenberg Hamiltonian we have studied the exchange-coupling matrix elements J for different chains. For the shorter chains, x≤2, we have included spin-orbit effects in the DFT calculations, extracting the magnetic anisotropy energy. Our results are also fitted to a simple anisotropic spin Hamiltonian and we have extracted values for the longitudinal-anisotropy D and transversal-anisotropy E constants. These parameters together with the values for J allow us to compute the magnetic excitation energies of the system and to compare them with the experimental data. [ABSTRACT FROM AUTHOR]

Variation in the biceps brachii muscle is extremely frequent and has a clinical significance. During an educational dissection, third head of the biceps brachii muscle was found on the left side in a Korean cadaver The short and long heads showed normal morphology and course: however, additional head originated from the greater tubercle connected to long head of biceps brachii muscle and crossed the musculocutaneous nerve perpendicularly. And then, it was inserted into short head of the biceps brachii muscle. The author describes this previously novel case report and discusses the clinical implications of such a variant. [ABSTRACT FROM AUTHOR]

Total knee arthroplasty has increased substantially, however anatomical studies of the genicular arteries (GAs) in this region are rare. The aim of this study was to identify the pattern and branching points of GAs and their relationship. In 42 lower limbs, the pattern and branching points of GAs were confirmed. The horizontal line which extends between the most prominent point of the lateral and medial margins of patella was defined as a reference line. The distance of branching point of the GAs from the reference line was measured and the correlations between these points were analyzed. The superior lateral and medial genicular arteries (SLGA and SMGA) were located at + 38.17 ± 3.10 mm and + 32.68 ± 3.83 mm from the reference line, respectively. The middle genicular artery (MGA) was originated from + 7.57 ± 3.98 mm. The inferior lateral and medial genicular arteries (ILGA and IMGA) were located at - 18.46 ± 2.63 mm and - 24.09 ± 3.52 mm, respectively. The branching points of the SLGA changed significantly according to the arterial branching pattern with the MGA. In addition, the branching point of the MGA had positive relationships with that of the IMGA (r = 0.385, p <0.05) and that of the ILGA (r = 0.348, p <0.05), respectively. In this study, topography of the GAs and its anatomical association were demonstrated for the first time in Korean cadavers. Knowledge of the topography about frequent variation would be useful for safe surgery and clinical procedures. [ABSTRACT FROM AUTHOR]