Search

By selecting appropriate microhabitats, animals gain various benefits. For amphibians, which are ectothermic, appropriate microhabitat selection is directly related to their survival. This study aims to characterize the microhabitat type selected by Bufo gargarizans in South Korea, which has not yet been examined, using radiotelemetry. We analyzed the percent cover of different microhabitat features at sites where B. gargarizans was found. The microhabitat was categorized into eight types: stacked dry leaves litter or hay, grass, naked field, stones/pebbles, fallen branches, alive or dead trees/shrubs, wetland, and other. We collected a total of 60 location data, all of which had closed cover. From these, nine hibernation sites and six post-breeding dormancy sites were identified. Dry leaf litter was found to be the most frequently selected microhabitat type. We also found significant differences in microhabitat type between the hibernation period and the post-breeding dormancy period. We considered that these differences can be explained by the ecological characteristics of B. gargarizans. [ABSTRACT FROM AUTHOR]

Recently, single-cell molecular analysis has been leveraged to achieve unprecedented levels of biological investigation. However, a lack of simple, high-throughput single-cell methods has hindered in-depth population-wide studies with single-cell resolution. We report a microwell-based cytometric method for simultaneous measurements of gene and protein expression dynamics in thousands of single cells. We quantified the regulatory effects of transcriptional and translational inhibitors on cMET mRNA and cMET protein in cell populations. We studied the dynamic responses of individual cells to drug treatments, by measuring cMET overexpression levels in individual non-small cell lung cancer (NSCLC) cells with induced drug resistance. Across NSCLC cell lines with a given protein expression, distinct patterns of transcript-protein correlation emerged. We believe this platform is applicable for interrogating the dynamics of gene expression, protein expression, and translational kinetics at the single-cell level - a paradigm shift in life science and medicine toward discovering vital cell regulatory mechanisms.

Pref-1 is an EGF-repeat-containing protein that inhibits adipocyte differentiation. To better understand the origin and development of white adipose tissue (WAT), we generated transgenic mouse models for transient or permanent fluorescent labeling of cells using the Pref-1 promoter, facilitating inducible ablation. We show that Pref-1-marked cells retain proliferative capacity and are very early adipose precursors, prior to expression of Zfp423 or PPARγ. In addition, the Pref-1-marked cells establish that adipose precursors are mesenchymal, but not endothelial or pericytal, in origin. During embryogenesis, Pref-1-marked cells first appear in the dorsal mesenteric region as early as embryonic day 10.5 (E10.5). These cells become lipid-laden adipocytes at E17.5 in the subcutaneous region, whereas visceral WAT develops after birth. Finally, ablation of Pref-1-marked cells prevents not only embryonic WAT development but also later adult adipose expansion upon high-fat feeding, demonstrating the requirement of Pref-1 cells for adipogenesis.

Leucism, in which pigmentation is lost over part or the entire body of an animal, has a range of possible genetic causes. Here, we report leucism in an individual tiger keelback (Rhabdophis tigrinus) found on Jeung Island, Shinan‐gun, Jeollanam‐do, South Korea, during a survey of the distribution of reptiles in the area. The individual was observed sunbathing in the bushes next to a pond. This individual exhibited ecdysis, thus it considered that have normal feeding activity. Our report represents the first observation of leucism in R. tigrinus, and thus, further analysis is needed of this phenotype to more clearly understand its impact on the species and its natural history. [ABSTRACT FROM AUTHOR]

Background: In patients with out‐of‐hospital cardiac arrest (OHCA), low blood pressure after return of spontaneous circulation (ROSC) can be a sign of hemodynamic instability. We aimed to investigate whether systolic blood pressure (SBP) measured immediately after ROSC is associated with survival on admission. Methods: Patients with ROSC after OHCA between 2015 and 2018 were included. The primary outcome was survival on admission. Included patients were divided into three groups based on the SBP measured at the time of ROSC: group 1 (SBP ≤90 mmHg), group 2 (SBP 90–120 mmHg), and group 3 (SBP >120 mmHg). Multivariable logistic regression was used to investigate the relationship between the groups by SBP and outcomes. Results: In the final analysis, 519 patients were included. In the restrictive cubic spline curve, the probability of achieving survival on admission increased gradually from low SBP to approximately 120–130 mmHg, then plateaued at a higher SBP. In the multivariable logistic regression analysis, group 1 was independently associated with decreased survival on admission compared to group 2. There was no significant difference between groups 2 and 3. Conclusions: Low blood pressure (SBP ≤90 mmHg) at the time of ROSC was independently associated with a lower likelihood of survival on admission in patients with non‐traumatic OHCA. However, high blood pressure (SBP >120 mmHg) was not associated with a higher likelihood of survival. These suggest that low blood pressure measured in the prehospital phase can serve as an indicator predicting the poor short‐term prognosis of patients. [ABSTRACT FROM AUTHOR]

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI–TOF MS) is a commonly used technique for analyzing large biomolecules. However, the utilization of organic matrices limits the small-molecule analysis because of the interferences in the low-mass region and the reproducibility issues. To overcome these limitations, a surface-assisted laser desorption/ionization (SALDI), which utilizes nanostructured metallic surfaces, has been developed. Herein, a novel approach for SALDI–MS was proposed using silica@gold core–shell hybrid materials with a nanogap-rich shell (SiO2@Au NGS), which is an emerging material due to its excellent heat-generating capabilities. The gold shell thickness was controlled by adjusting the concentration of gold precursor for the growth of gold nanoparticles. SALDI-MS measurements were performed on a layer formed by drop-casting a mixture of SiO2@Au NGS and analytes. At the optimized process, the gold shell thickness was observed to be 17.2 nm, which showed the highest absorbance. Based on the enhanced SALDI capability, SiO2@Au NGS was utilized to detect various small molecules, including amino acids, sugars, and flavonoids, and the ionization softness was confirmed with a survival yield upon fragmentation. The limits of detection, reproducibility, and salt tolerance of SiO2@Au NGS demonstrate its potential as an effective and reliable SALDI material for small-molecule analyses. [ABSTRACT FROM AUTHOR]

The optical features of multiple‐layered axial heterostructures composed of III‐nitride semiconductors (GaN, InGaN, and AlGaN) are investigated to realize tunable nanolasers. The optical confinement effects develop exciton‐polariton in nanorods, leading to polariton lasing with distinctive dispersion. The lasing characteristics in the heterostructure are similar to those in the homostructure, although the carrier transfer between layers influences the optical gain. The energy‐dependent property of polariton changes the mode spacing of lasing peaks. The alloyed systems of InGaN can tune the color of lasing in the visible region, while the lasing of AlGaN is also achievable in the optimized configuration. The polarization of lasing indicates the predominant contribution of the fundamental transverse mode. Therefore, in the multiple‐layered heterostructure, controllable triple‐color lasing using the feature of polariton, modulation of band gap energy, and the amplification process of the waveguide is demonstrated for the first time, with the tunable color over a wide range of the visible region. Multicolor polariton nanolasers offer a promising path to diverse nanophotonic devices with controllable optical characteristics. [ABSTRACT FROM AUTHOR]

Genetic, environment, and behaviour factors have a role in causing sudden cardiac arrest (SCA). We aimed to determine the strength of the association between various risk factors and SCA incidence. We conducted a multicentre case-control study at 17 hospitals in Korea from September 2017 to December 2020. The cases included out-of-hospital cardiac arrest aged 19–79 years with presumed cardiac aetiology. Community-based controls were recruited at a 1:1 ratio after matching for age, sex, and urban residence level. Multivariable conditional logistic regression analysis was conducted. Among the 1016 cases and 1731 controls, 948 cases and 948 controls were analysed. A parental history of SCA, low educational level, own heart disease, current smoking, and non-regular exercise were associated with SCA incidence (Adjusted odds ratio [95% confidence interval]: 2.51 [1.48–4.28] for parental history of SCA, 1.37 [1.38–2.25] for low edication level, 3.77 [2.38–5.90] for non-coronary artery heart disease, 4.47 [2.84–7.03] for coronary artery disease, 1.39 [1.08–1.79] for current smoking, and 4.06 [3.29–5.02] for non-regular exercise). Various risk factors related to genetics, environment, and behaviour were independently associated with the incidence of SCA. Establishing individualised SCA prevention strategies in addition to general prevention strategies is warranted. [ABSTRACT FROM AUTHOR]

Sternotherus carinatus has been considered as a potential invasive species in Korea. However, the mitochondrial genome information of S. carinatus which can be used to control its effect on ecosystem is lacking. In this study, the complete mitochondrial genome of S. carinatus in Korea was sequenced and characterized. The mitochondrial genome consists of 37 genes (13 protein-coding genes, 22 transfer RNA genes, and 2 ribosomal RNA genes) and a noncoding region. Phylogenetic analysis based on the mitochondrial genome sequences showed that S. carinatus from Korea is separated from other turtles which are the invasive species in Korea. Sequence divergence calculations indicated near-zero divergence between S. carinatus populations in Korea, the USA, and China, suggesting limited genetic differentiation. In the context of the broader issue of invasive species disrupting ecosystems, this research contributes to the identification of mitochondrial genomes for various freshwater turtle species, emphasizing the need for extended data collection to discern genetic mixing trends between native and non-native species. This study is a significant step toward managing S. carinatus as a potential invasive species in Korea. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome of Chrysemys picta bellii in Korea was sequenced and characterized. The mitochondrial genome consists of 37 genes (13 protein-coding genes, 22 transfer RNA genes, and 2 ribosomal RNA genes) and a noncoding region. Phylogenetic analysis based on the mitochondrial genome sequences revealed that C. p. bellii from Korea formed a cluster with C. p. bellii from China and C. picta from the USA, while showing clear separation from other turtle species within the C. picta cluster. This study presented the first complete mitochondrial genome from C. p. bellii in Korea, offering crucial information for managing invasive species and protecting the local ecosystem. [ABSTRACT FROM AUTHOR]