Toxic effects of fragmented polyethylene terephthalate particles on the marine rotifer Brachionus koreanus: Based on ingestion and egestion assay, in vivo toxicity test, and multi-omics analysis.

Microplastics (MPs) are a major concern in marine ecosystem because MPs are persistent and ubiquitous in oceans and are easily consumed by marine biota. Although many studies have reported the toxicity of MPs to marine biota, the toxicity of environmentally relevant types of MPs is little understood. We investigated the toxic effects of fragmented polyethylene terephthalate (PET) MP, one of the most abundant MPs in the ocean, on the marine rotifer Brachionus koreanus at the individual and molecular level. No significant rotifer mortality was observed after exposure to PET MPs for 24 and 48 h. The ingestion and egestion assays showed that rotifers readily ingested PET MPs in the absence of food but not when food was supplied; thus, there were also no chronic effects of PET MPs. In contrast, intracellular reactive oxygen species levels and glutathione S-transferase activity in rotifers were significantly increased by PET MPs. Transcriptomic and metabolomic analyses revealed that genes and metabolites related to energy metabolism and immune processes were significantly affected by PET MPs in a concentration-dependent manner. Although acute toxicity of PET MPs was not observed, PET MPs are potentially toxic to the antioxidant system, immune system, and energy metabolism in rotifers.

Treatment of Osteoporosis after Hip Fracture: Survey of the Korean Hip Society.

Purpose: To assess current practice in the treatment of osteoporosis in patients who underwent treatment for hip fracture in South Korea. Materials and Methods: A survey of 97 members of the Korean Hip Society, orthopedic hip surgeons who administer treatment for hip fractures in South Korea, was conducted. The survey was conducted for assessment of demographic data and perceptions regarding the management of osteoporosis in patients who have undergone treatment for hip fracture. Analysis of the data was performed using descriptive statistical methods. Results: The majority of participants were between the age of 41 and 50 years, and 74% were practicing in tertiary hospitals. Testing for serum vitamin D levels (82%) was the most commonly performed laboratory test. Calcium and vitamin D were prescribed for more than 80% of patients by 47% and 52% of participants, respectively. Denosumab was the most commonly used first-line treatment option for osteoporosis in hip fracture patients. Bisphosphonate was most often perceived as the cause of atypical femoral fractures, and the most appropriate time for reoperation was postoperative 12 months. Teriparatide was most preferred after cessation of bisphosphonate and only prescribing calcium and vitamin D was most common in high-risk patients for prevention of atypical femoral fracture. Conclusion: The results of this study that surveyed orthopedic hip surgeons showed that most participants followed the current strategy for management of osteoporosis. Because the end result of osteoporosis is a bone fracture, active involvement of orthopedic surgeons is important in treating this condition.

Quantitative real-time PCR analysis of four genetically modified soybean events using plasmid and genomic DNA calibrators.

A calibration curve is required for reliable and accurate quantitative real-time PCR analysis of genetically modified (GM) organisms, necessitating the use of reference materials as calibrators. In this study, two types of DNA calibrators-plasmid DNA (pDNA) and genomic DNA (gDNA)-were used to quantify four GM soybean events (SYHT0H2, MON87751, DAS-44406-6, and DAS-81419-2). The PCR efficiency and linearity for the calibrators adhered to the CODEX guidelines. The conversion factor (Cf) was calculated as the ratio of copies of GM events to those of endogenous genes using the pDNA calibration curve. To assess the accuracy and repeatability of these assays, quantification at GM levels of 3% and 1% was performed. Based on our results, we believe that the pDNA calibrator assessed in this study can be used as a reference material for GMO quantitative analysis and can replace gDNA, especially considering the ease of management and advantages of mass production. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01392-0.

Five new species of Bryaxis Kugelann (Coleoptera, Staphylinidae, Pselaphinae) from Korea and a nomenclatural note on Bryaxismahunkai Löbl.

The genus Bryaxis Kugelann (Goniaceritae: Bythinini) is the most species-rich genus of the subfamily Pselaphinae and is mainly distributed in the Palearctic region. Although previous studies have documented 14 species in the Korean Peninsula, the true diversity, ecology, and immature stages of the genus are still inadequately known. In this study, five new Korean species are described: B.grandinodussp. nov., B.uljinensissp. nov., B.fabaiformissp. nov., B.girinensissp. nov., and B.nemorosussp. nov. Illustrations of the habitus and other morphological details, and a distribution map are provided. In addition, Bryaxisleechanyoungi Nomura & Lee, 1993 is proposed as a new synonym of B.mahunkai Löbl, 1975 based on the original description and illustrations of diagnostic characters.

Prevention of Venous Thromboembolism in Patients Undergoing Hip Fracture Surgery: A Survey of the Korean Hip Society.

Purpose: The aim of this study was to assess the current status of venous thromboembolism (VTE) prevention in Korean patients with hip fractures. Materials and Methods: A survey using a questionnaire on the experiences and protocols of VTE prevention was conducted among 570 members of the Korean Hip Society. Results: A total of 97 surgeons responded, with a response rate of 17.0%. Of the 97 participants, 61.9% answered that they had encountered one or more cases of symptomatic VTE in the past year. Mechanical prophylaxis was applied most often (30.9%) until the point of ambulation in standard-risk patients and most often (34.0%) extended until discharge in high-risk patients. Chemical prophylaxis was most often prescribed for a particular period of time rather than for recovery of walking ability (24.7% in standard-risk patients and 26.8% in high-risk patients). Dual prophylaxis was administered in the standard-risk group by 58.8% of the participants and in the high-risk group by 83.5%. Among the participants, 73.2% answered that they had been attentive to wound complications during chemical prophylaxis. More than half of the participants (59.8%) reported that they did not perform routine screening for VTE after surgery. Conclusion: The results of our survey provided information regarding the current status of VTE prevention for patients undergoing surgery for treatment of hip fractures in Korea as well as a baseline for establishment of educational programs and guidelines in the future.

Treatment of Femoral Neck Fractures in the Elderly: A Survey of the Korean Hip Society Surgeons.

Purpose: This study examined the methods for treatment of femoral neck fracture (FNF) preferred by members of the Korean Hip Society (KHS) and identified factors that influence decisions regarding the surgical intervention of choice. Materials and Methods: A total of 97 members of the KHS responded to the 16-question survey which included questions about the mean number of surgeries performed each month for treatment of femoral neck fractures, the cut-off age for deciding between internal fixation and arthroplasty, the implant used most often, usage of cement, and factors influencing each decision. Results: The mean cut-off age used when deciding between internal fixation and arthroplasty was 64 years old. Hemiarthroplasty (HA) (70%) was the most preferred option for treatment of displaced FNFs in cases where arthroplasty was indicated (total hip arthroplasty [THA] 19% and dual mobility THA 11%). The main reasons for selection of arthroplasty over reduction with internal fixation were age and pre-fracture ambulatory status. Pre-trauma ambulatory status and/or sports activity were the main factors in selection of HA over THA. Cement was used by 33% of responders. Poor bone quality and a broad femoral canal were factors that influenced the usage of cement. Conclusion: Management of FNFs in the elderly is a major health problem worldwide; thus, remaining alert to current trends in treatment is essential for surgeons. The mean cut-off age used in deciding between internal fixation and arthroplasty was 64 years old. HA is the preferred method for treatment of displaced FNFs for members of the KHS.

Three new species of the subfamily Nossidiinae (Coleoptera: Ptiliidae) from South Korea.

The subfamily Nossidiinae was established in 2019 and is comprised of five genera including one fossil genus. Among them, Nossidium Erichson and Sindosium Johnson share many morphological similarities. To this point, two extant Nossidium-species, N. flachi Ganglbauer and N. pilosellum (Marsham) have been recorded in the Palaearctic realm. In this paper, we describe three new species, Nossidium koreanum sp. nov., Sindosium longifilum sp. nov. and S. chungbukicum sp. nov. from South Korea. These are the first Nossidiinae species described from Korea, as well as the first Palaearctic record of the genus Sindosium.

Pathway-dependent toxic interaction between polystyrene microbeads and methylmercury on the brackish water flea Diaphanosoma celebensis: Based on mercury bioaccumulation, cytotoxicity, and transcriptomic analysis.

Given their worldwide distribution and toxicity to aquatic organisms, methylmercury (MeHg) and microplastics (MP) are major pollutants in marine ecosystems. Although they commonly co-exist in the ocean, information on their toxicological interactions is limited. Therefore, to understand the toxicological interactions between MeHg and MP (6-µm polystyrene), we investigated the bioaccumulation of MeHg, its cytotoxicity, and transcriptomic modulation in the brackish water flea Diaphanosoma celebensis following single and combined exposure to MeHg and MP. After single exposure to MeHg for 48-h, D. celebensis showed high Hg accumulation (34.83 ± 0.40 µg/g dw biota) and cytotoxicity, which was reduced upon co-exposure to MP. After transcriptomic analysis, 2, 253, and 159 differentially expressed genes were detected in the groups exposed to MP, MeHg, and MeHg+MP, respectively. Genes related to metabolic pathways and the immune system were significantly affected after MeHg exposure, but the effect of MeHg on these pathways was alleviated by MP co-exposure. However, MeHg and MP exhibited synergistic effects on the expression of gene related to DNA replication. These findings suggest that MP can reduce the toxicity of MeHg but that their toxicological interactions differ depending on the molecular pathway.

Bipolar Hemiarthroplasty in Unstable Intertrochanteric Fractures with an Effective Wiring Technique.

Purpose: Bipolar hemiarthroplasty has recently been acknowledged as an effective option for treatment of unstable intertrochanteric fracture. Trochanteric fragment nonunion can cause postoperative weakness of the abductor muscle and dislocation; therefore, reduction and fixation of the fragment is essential. The purpose of this study was to perform an evaluation and analysis of the outcomes of bipolar hemiarthroplasty using a useful wiring technique for management of unstable intertrochanteric fractures. Materials and Methods: A total of 217 patients who underwent bipolar hemiarthroplasty using a cementless stem and a wiring technique for management of unstable intertrochanteric femoral fractures (AO/OTA classification 31-A2) at our hospital from January 2017 to December 2020 were included in this study. Evaluation of clinical outcomes was performed using the Harris hip score (HHS) and the ambulatory capacity reported by patients was classified according to Koval stage at six months postoperatively. Evaluation of radiologic outcomes for subsidence, breakage of wiring, and loosening was also performed using plain radiographs at six months postoperatively. Results: Among 217 patients, five patients died during the follow-up period as a result of problems unrelated to the operation. The mean HHS was 75±12 and the mean Koval category before the injury was 2.5±1.8. A broken wire was detected around the greater trochanter and lesser trochanter in 25 patients (11.5%). The mean distance of stem subsidence was 2.2±1.7 mm. Conclusion: Our wiring fixation technique can be regarded as an effective additional surgical option for fixation of trochanteric fracture fragments during performance of bipolar hemiarthroplasty.

Complete mitochondrial genome of the Chinese Callipogon (Eoxenus) relictus (Cerambycidae: Prioninae) with phylogenetic analyses.

BACKGROUND: The endangered longhorn beetle Callipogon (Eoxenus) relictus, which was designated as a natural monument since 1968 in Korea is still attracting public concern because of its extraordinary body size. Although mitochondrial genome data of this species was reported using Korean individual in 2017, start codon of cox1 is controversial and the secondary structures of transfer RNAs have not been illustrated. OBJECTIVE: To report complete mitochondrial genome of Callipogon (Eoxenus) relictus from Chinese breed. METHODS: We used dissected muscle tissues from an adult of Callipogon (Eoxenus) relictus. A total of 19,276,266,645 bp from 127,657,395 reads were generated. The raw reads were assembled to mitochondrial genome data and annotated. Folded structures of transfer RNAs were drawn. Phylogenetic relationships were estimated by maximum likelihood and Bayesian inference analyses. RESULTS: The mitochondrial genome of C. relictus was 15,745 bp in length and composed of 37 genes including 13 protein-coding genes (PCGs), two ribosomal RNAs, and 22 transfer RNAs. The overall base composition was 38.40% for A, 30.98% for T, 11.06% for G, and 19.56% for C. Most transfer RNAs were folded into the typical clover-leaf structure except trnS1. Phylogenetic analyses confirmed the monophyletic status of each subfamily. CONCLUSION: Mitochondrial genome composition was consistent with previous research, however, we suggest another start codon of cox1 gene and provide illustrated secondary structures of transfer RNAs. Phylogenetic analyses showed that subfamilies Cerambycinae and Prioninae are closely related.

Complete mitochondrial genome of Aleochara (Aleochara) curtula (Goeze, 1777) (Coleoptera: Staphylinidae).

The mitochondrial genome (mitogenome) of Aleochara (Aleochara) curtula (Goeze, 1777) (Coleoptera: Staphylinidae) is reported. This mitogenome (GenBank accession no. OL675411) is 16,600 bp in size and consists of 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), and two ribosomal RNA genes (rRNA). Most PCGs use typical mitochondrial stop codon (TAR) except for cox3, which uses a single T residue. The A, G, T, and C nucleotide base composition of the mitogenome is 40.61%, 7.66%, 40.34%, and 11.39%, respectively. The phylogenetic analyses recovered the monophyly of Aleocharinae.

Effective BMP-2 Release and Mineralization on a Graphene Oxide/Polyvinylpyrrolidone Hydrogel Forming Poly (ε-Caprolactone) Nanofibrous Scaffolds.

PCL nanofibrous scaffolds are widely used as bone scaffolds, and they can increase the efficiency of bone regeneration by loading drugs and/or growth factors onto them. However, to obtain a more effective bone regeneration effect, it is necessary to increase drug loading and release efficiency. In this study, conductive hydrogel forming nanofibrous scaffolds were prepared to increase drug efficiency. GO has an excellent conductivity and biocompatibility, making it an efficient conductive polymer for bone differentiation. Electrospun PCL was immersed in a mixed solution of GO and PVP and then crosslinked using gamma-ray irradiation. It was confirmed that GO/PVP-PCL was successfully prepared through its characterization (morphology, thermal, chemical, electrical, and biological properties). In addition, drug-release efficiency was confirmed by electrical stimulation after loading the sample with BMP-2, a bone-regeneration growth factor. Compared to PCL, it was confirmed that GO/PVP-PCL has an approximately 20% improved drug-release efficiency and an excellent mineralization of the scaffolds using SBF. After culturing MG63 cells on GO/PVP-PCL, a high effect on osteodifferentiation was confirmed by ALP activity. Therefore, GO/PVP-PCL prepared by a gamma-ray-induced crosslinking reaction is expected to be used as biomaterial for bone-tissue engineering.

Optimization of the Physical Properties of HDPE/PU Blends through Improved Compatibility and Electron Beam Crosslinking.

Polymer blending is a method in which polymers with different properties are mixed so that each advantage appears in one polymer blend. Improved thermal and mechanical properties of blends can be prepared by blending with high-density polyethylene (HDPE) of a non-polar polymer and polyurethane (PU) of a polar polymer. However, a compatibilizer is required because it has the disadvantage that blending has low miscibility due to the different phases. In this study, HDPE/PU blends with new and excellent physical properties were developed through optimal composition with improved compatibility between the HDPE and PU. In addition, the effects of improving the physical properties through electron-beam crosslinking were confirmed. In general, a crosslinking structure of HDPE is formed by electron beam irradiation to increase its thermal stability and strength, but its elongation is rapidly decreased. In particular, the elongation of HDPE irradiated at 100 kGy was about 110%, which was decreased about five times compared to unirradiated HDPE (510%). However, the HDPE/PU blend with improved compatibility (PU 30) showed an elongation of about 450% while maintaining excellent strength (22.5 MPa), which was increased by about four times compared to the HDPE irradiated at 100 kGy. In particular, the thermal stability of PU 30 irradiated at 100 kGy at a high temperature (180 °C) was improved more than six times compared to the HDPE. Therefore, it is possible to develop HDPE/PU blends with new and excellent physical properties by improving compatibility and using electron beam crosslinking technology.

Development of markers using microsatellite loci of two rove beetle species, Paederus fuscipes Curtis and Aleochara (Aleochara) curtula Goeze (Coleoptera: Staphylinidae), followed by analyses of genetic diversity and population structure.

BACKGROUND: The family Staphylinidae is the most speciose beetle group in the world. The outbreaks of two staphylinid species, Paederus fuscipes and Aleochara (Aleochara) curtula, were recently reported in South Korea. None of research about molecular markers and genetic diversity have been conducted in these two species. OBJECTIVE: To develop microsatellite markers and analyze the genetic diversity and population structures of two rove beetle species. METHODS: NGS was used to sequence whole genomes of two species, Paederus fuscipes and Aleochara (Aleochara) curtula. Microsatellite loci were selected with flanking primer sequences. Specimens of P. fuscipes and A. curtula were collected from three localities, respectively. Genetic diversity and population structure were analyzed using the newly developed microsatellite markers. RESULTS: The number of alleles ranged 5.727-6.636 (average 6.242) and 2.182-5.364 (average 4.091), expected heterozygosity ranged 0.560-0.582 (average 0.570) and 0.368-0.564 (average 0.498), observed heterozygosity ranged 0.458-0.497 (average 0.472) and 0.418-0.644 (average 0.537) in P. fuscipes and A. curtula, respectively. Population structure indicates that individuals of A. curtula are clustered to groups where they were collected, but those of P. fuscipes are not. CONCLUSION: Population structures of P. fuscipes were shallow. In A. curtula, however, it was apparent that the genetic compositions of the populations are different significantly depending on collection localities.

Bone Regeneration by Multichannel Cylindrical Granular Bone Substitute for Regeneration of Bone in Cases of Tumor, Fracture, and Arthroplasty.

In orthopedics, a number of synthetic bone substitutes are being used for the repair and regeneration of damaged or diseased bone. The nature of the bone substitutes determines the clinical outcome and its application for a range of orthopedic clinical conditions. In this study, we aimed to demonstrate the possible applications of multichannel granular bone substitutes in different types of orthopedic clinical conditions, including bone tumor, fracture, and bone defect with arthroplasty. A clinical investigation on a single patient for every specific type of disease was performed, and patient outcome was evaluated by physical and radiographic observation. Brief physical characterization of the granular bone substitute and in vivo animal model investigation were presented for a comprehensive understanding of the physical characteristics of the granules and of the performance of the bone substitute in a physiological environment, respectively. In all cases, the bone substitute stabilized the bone defect without any complications, and the defect regenerated slowly during the postoperative period. Gradual filling of the defect with the newly regenerated bone was confirmed by radiographic findings, and no adverse effects, such as osteolysis, graft dispersion, and non-union, were observed. Homogeneous bone formation was observed throughout the defect area, showing a three-dimensional bone regeneration. High-strength multichannel granules could be employed as versatile bone substitutes for the treatment of a wide range of orthopedic conditions.

Review of the Korean Species of the Genus Edaphus Motschulsky (Coleoptera, Staphylinidae) with Description of Four New Species.

The cosmopolitan euaesthetine genus, Edaphus Motschulsky, 1857, with about 90 Palaearctic species, was formerly known by a single species, E. koreanus Puthz, 2011, of which 2 specimens were collected in the southern part of the Korean Peninsula. In this paper, the knowledge of the Korean Edaphus fauna is expanded to include six species, including four described here based on a rich material collected in recent years. A key to all six species of Korean Edaphus, illustration of the habitus and diagnostic characters, and a distribution map are provided.

Subtrochanteric Insufficiency Fracture Occurring 5 Years after Surgery at the Steinmann Pin Insertion Site for Fracture Reduction.

Background and Objectives: Steinmann pins are commonly used in orthopedics, with a low rate of complications. However, thermal osteonecrosis may occur when a pin is inserted using a drill. There have been no reports on late-onset fractures at the Steinmann pin insertion site. Materials and Methods: A 32-year-old man who underwent surgery for a femoral shaft fracture 5 years ago complained of proximal thigh pain 1 month after the removal of the internal device. On physical examination, the patient showed a limping gait due to pain, and tenderness was observed on the lateral aspect of the proximal thigh. Magnetic resonance imaging was performed because the symptoms did not improve, despite conservative treatment. A new fracture line was observed in the lateral cortical bone of the proximal femur. It was found that a fracture occurred at the site where the Steinmann pin was inserted for a closed reduction at the time of the first operation. The patient was instructed to limit weight bearing and to use crutches while walking. Parathyroid hormone was additionally administered to promote bone formation. Results: Six months after diagnosis, a complete union was achieved at the subtrochanteric fracture site, and the patient's pain subsided. Conclusions: A fracture that occurs as a late onset at the provisional Steinmann pin insertion site is an extremely rare complication; however, orthopedic surgeons must consider this possibility and make more efforts to lower the occurrence of thermal damage. In addition, if the patient complains of pain in the region where the pin was inserted after surgery, surgeons should spare no effort to determine whether a new fracture has occurred.

In Vivo Evaluation of Gamma-Irradiated and Heparin-Immobilized Small-Diameter Polycaprolactone Vascular Grafts with VEGF in Aged Rats.

The effectiveness of small-diameter vascular grafts depends on their antithrombogenic properties and ability to undergo accelerated endothelialization. The extreme hydrophobic nature of poly(ε-caprolactone) (PCL) hinders vascular tissue integration, limiting its use in medical implants. To enhance the antithrombogenicity of PCL as a biomaterial, we grafted 2-aminoethyl methacrylate (AEMA) hydrochloride onto the PCL surface using gamma irradiation; developed a biodegradable heparin-immobilized PCL nanofibrous scaffold using gamma irradiation and N-(3-dimethylaminopropyl)-N'-ethyl carbodiimide hydrochloride/N-hydroxysuccinimide reaction chemistry; and incorporated vascular endothelial growth factor (VEGF) into the scaffold to promote vascular endothelial cell proliferation and prevent thrombosis on the vascular grafts. We assessed the physicochemical properties of PCL, heparin-AEMA-PCL (H-PCL), and VEGF-loaded heparin-AEMA-PCL (VH-PCL) vascular grafts using scanning electron microscopy, attenuated total reflection-Fourier transform infrared spectroscopy, toluidine blue O staining, and fibrinogen adsorption and surface wettability measurement. In addition, we implanted the vascular grafts into 24-month-old Sprague Dawley rats and evaluated them for 3 months. The H-PCL and VH-PCL vascular grafts improved the recovery of blood vessel function by promoting the proliferation of endothelial cells and preventing thrombosis in clinical and histological evaluation, indicating their potential to serve as functional vascular grafts in vascular tissue engineering.

Postnatal regulation of B-1a cell development and survival by the CIC-PER2-BHLHE41 axis.

B-1 cell development mainly occurs via fetal and neonatal hematopoiesis and is suppressed in adult bone marrow hematopoiesis. However, little is known about the factors inhibiting B-1 cell development at the adult stage. We report that capicua (CIC) suppresses postnatal B-1a cell development and survival. CIC levels are high in B-1a cells and gradually increase in transitional B-1a (TrB-1a) cells with age. B-cell-specific Cic-null mice exhibit expansion of the B-1a cell population and a gradual increase in TrB-1a cell frequency with age but attenuated B-2 cell development. CIC deficiency enhances B cell receptor (BCR) signaling in transitional B cells and B-1a cell viability. Mechanistically, CIC-deficiency-mediated Per2 derepression upregulates Bhlhe41 levels by inhibiting CRY-mediated transcriptional repression for Bhlhe41, consequently promoting B-1a cell formation in Cic-null mice. Taken together, CIC is a key transcription factor that limits the B-1a cell population at the adult stage and balances B-1 versus B-2 cell formation.

Regulation of positive and negative selection and TCR signaling during thymic T cell development by capicua.

Central tolerance is achieved through positive and negative selection of thymocytes mediated by T cell receptor (TCR) signaling strength. Thus, dysregulation of the thymic selection process often leads to autoimmunity. Here, we show that Capicua (CIC), a transcriptional repressor that suppresses autoimmunity, controls the thymic selection process. Loss of CIC prior to T-cell lineage commitment impairs both positive and negative selection of thymocytes. CIC deficiency attenuated TCR signaling in CD4+CD8+ double-positive (DP) cells, as evidenced by a decrease in CD5 and phospho-ERK levels and calcium flux. We identified Spry4, Dusp4, Dusp6, and Spred1 as CIC target genes that could inhibit TCR signaling in DP cells. Furthermore, impaired positive selection and TCR signaling were partially rescued in Cic and Spry4 double mutant mice. Our findings indicate that CIC is a transcription factor required for thymic T cell development and suggests that CIC acts at multiple stages of T cell development and differentiation to prevent autoimmunity.