Digital coincidence counting with 4πβ(PPC)-γ for the standardization of 60Co

A 4πβ(PPC)-γ coincidence system has been made at KRISS based on a digital DAQ. 60Co sources were measured to verify the system. The maximum detection efficiency for beta particles was estimated to be 96.7 %. Massic activities for sample sources had 0.005 % of the sample variability error, which was well within the expanded standard uncertainty of 0.54 % (k = 2).

A Prospective Study of Bevacizumab and Neoadjuvant Concurrent Chemoradiation in Locally Advanced Esophageal Squamous Cell Carcinoma: Paradoxical Increase in Circulating Vascular Endothelial Growth Factor-A and Effect on Outcome

PURPOSE/OBJECTIVE(S)

In the prior prospective biomarker study, high serum vascular endothelial growth factor-A (VEGF-A) was associated with a poor prognosis. We conducted a prospective phase II trial of adding Bevacizumab, an anti-VEGF-A monoclonal antibody, to neoadjuvant concurrent chemoradiation (neoCCRT) for patients with locally advanced esophageal squamous cell carcinoma (LA-ESCC). This prospective biomarker study aims to evaluate the expressions of angiogenesis-associated circulating biomarkers before and after neoCCRT and compare clinical outcomes for patients receiving platinum/5-fluorouracil (PF) with or without Bevacizumab.

MATERIALS/METHODS

Patients with biopsy-proven resectable non-T4 LA-ESCC were enrolled for the prospective phase II trial investigating PF-neoCCRT plus Bevacizumab (BPF group). A parallel patient cohort enrolled in a prospective biomarker study receiving PF-neoCCRT was included in the present analysis as the control group (PF group). Radiotherapy was delivered with 40 Gy in 20 fractions. All patients had restaging workups after enoCCRT and underwent radical esophagectomy if the disease remained resectable. Serums were collected before and after neoCCRT. The serum concentrations of angiogenesis-associated biomarkers were determined by the multiplex enzyme-linked immunosorbent assay. Survival analyses were performed by the Kaplan-Meier method. The t-test and log-rank test were used to compare differences in biomarker expression and survival between groups.

RESULTS

From 2016 to 2019, 43 patients (BPF/PF group: 21/22) were enrolled in the study. Twenty patients in each group had serum samples available for biomarker analysis. 15 out of 21 patients in the BPF group and 20 out of 22 patients in the PF group underwent radical esophagectomy. Six patients in the BPF group and nine patients in the PF group achieved pathological complete responses. The median overall survival for the BPF and PF group was 20.8 months and not-reached, respectively (hazard ratio = 1.33, long rank p = 0.58). In the BPF group, the serum VEGF-A level was significantly increased from an average value of 446 pg/mL to 723 pg/mL after neoCCRT (p = 0.037), while its level was decreased from 815 ng/mL to 380 pg/mL in the PF group (p = 0.104). In addition, the expression value of circulating Angiopoietin-1 was not changed in the BPF group (before neoCCRT, mean value = 828 pg/mL; after neoCCRT, mean value 762 pg/mL, p = 0.67). In contrast, serum Angiopoietin-1 level was reduced from an average value of 659 pg/mL before neoCCRT to 271 pg/mL after neoCCRT (p = 0.002) in the PF group.

CONCLUSION

The addition of Bevacizumab to PF-neoCCRT did not improve pathological or survival outcomes in patients with resectable LA-ESCC. Adding a single dose of Bevacizumab paradoxically increases circulating VEGF-A while maintaining the Angiopoietin-1 serum level after neoCCRT. Further investigation by using additional VEGF-A inhibition may be required to achieve sustained angiogenesis blocked for tumor control.

Comprehensive Transcriptome Analysis in the Testis of the Silkworm, Bombyx mori

Spermatogenesis is an important process in reproduction and is conserved across species, but in Bombyx mori, it shows peculiarities, such as the maintenance of spermatogonia by apical cells and fertilization by dimorphic spermatozoa. In this study, we attempted to characterize the genes expressed in the testis of B. mori, focusing on aspects of expression patterns and gene function by transcriptome comparisons between different tissues, internal testis regions, and Drosophila melanogaster. The transcriptome analysis of 12 tissues of B. mori, including those of testis, revealed the widespread gene expression of 20,962 genes and 1705 testis-specific genes. A comparative analysis of the stem region (SR) and differentiated regions (DR) of the testis revealed 4554 and 3980 specific-enriched genes, respectively. In addition, comparisons with D. melanogaster testis transcriptome revealed homologs of 1204 SR and 389 DR specific-enriched genes that were similarly expressed in equivalent regions of Drosophila testis. Moreover, gene ontology (GO) enrichment analysis was performed for SR-specific enriched genes and DR-specific enriched genes, and the GO terms of several biological processes were enriched, confirming previous findings. This study advances our understanding of spermatogenesis in B. mori and provides an important basis for future research, filling a knowledge gap between fly and mammalian studies.

Tributyltin-binding protein type 1 (fish acid glycoprotein) is a potential gatekeeper of ethinylestradiol action in fish

Tributyltin (TBT)-binding protein type 1 in Japanese medaka (Oryzias latipes) (O.latTBT-bp1) is a fish lipocalin implicated in TBT binding and detoxification. We purified recombinant O.latTBT-bp1 (rO.latTBT-bp1; ca. 30 kDa) by using a baculovirus expression system and His- and Strep-tag chromatography process. Then, we examined O.latTBT-bp1 binding to several endo/exogenous steroid hormones by means of competitive binding assay. The dissociation constants for the binding of rO.latTBT-bp1 to DAUDA and ANS, two fluorescent ligands of lipocalin, were 7.06 and 13.6 μM, respectively. Multiple model validations indicated that a single-binding-site model was the most appropriate for evaluating rO.latTBT-bp1 binding. In the competitive binding assay, testosterone, 11-ketotestosterone, and 17β-estradiol were each bound by rO.latTBT-bp1; rO.latTBT-bp1 showed the strongest affinity for testosterone (inhibition constant, K_i = 3.47 μM). Endocrine-disrupting chemical (synthetic steroid) also bound to rO.latTBT-bp1; the affinity for ethinylestradiol (K_i = 9.29 μM) was stronger than that for 17β-estradiol (K_i = 30.0 μM). To determine the function of O.latTBT-bp1, we produced TBT-bp1 knockout medaka (TBT-bp1 KO), which we exposed to ethinylestradiol for 28 days. After exposure, the number of papillary processes in TBT-bp1 KO genotypic male medaka was significantly fewer (3.5), compared to that in wild-type male medaka (22). Thus, TBT-bp1 KO medaka were more sensitive to the anti-androgenic effects of ethinylestradiol than wild-type medaka. These results indicate that O.latTBT-bp1 may bind to steroids and act as a gatekeeper of ethinylestradiol action by regulating the androgen-estrogen balance.

The biological role of core 1β1-3galactosyltransferase (T-synthase) in mucin-type O-glycosylation in Silkworm, Bombyx mori

O-glycosylation of secreted and membrane-bound proteins is an important post-translational modification that affects recognition of cell surface receptors, protein folding, and stability. However, despite the importance of O-linked glycans, their biological functions have not yet been fully elucidated and the synthetic pathway of O-glycosylation has not been investigated in detail, especially in the silkworm. In this study, we aimed to investigate O-glycosylation in silkworms by analyzing the overall structural profiles of mucin-type O-glycans using LC-MS. We found GalNAc or GlcNAc monosaccharide and core 1 disaccharide (Galβ1-3-GalNAcα1-Ser/Thr) were major components of the O-glycan attached to secreted proteins produced in silkworms. Furthermore, we characterized the 1 b1,3-galactosyltransferase (T-synthase) required for synthesis of the core 1 structure, common to many animals. Five transcriptional variants and four protein isoforms were identified in silkworms, and the biological functions of these isoforms were investigated. We found that BmT-synthase isoforms 1 and 2 were localized in the Golgi apparatus in cultured BmN4 cells and functioned both in cultured cells and silkworms. Additionally, a specific functional domain of T-synthase, called the stem domain, was found to be essential for activity and is presumed to be needed for dimer formation and galactosyltransferase activity. Altogether, our results elucidated the O-glycan profile and function of T-synthase in the silkworm. Our findings allow the practical comprehension of O-glycosylation required for employing silkworms as a productive expression system.

Transient disruption of functional connectivity and depression of neural fluctuations in a mouse model of acute septic encephalopathy

Septic encephalopathy leads to major and costly burdens for a large percentage of admitted hospital patients. Elderly patients are at an increased risk, especially those with dementia. Current treatments are aimed at sedation to combat mental status changes and are not aimed at the underlying cause of encephalopathy. Indeed, the underlying pathology linking together peripheral infection and altered neural function has not been established, largely because good, acutely accessible readouts of encephalopathy in animal models do not exist. Behavioral testing in animals lasts multiple days, outlasting the time frame of acute encephalopathy. Here, we propose optical fluorescent imaging of neural functional connectivity (FC) as a readout of encephalopathy in a mouse model of acute sepsis. Imaging and basic behavioral assessment were performed at baseline, Hr8, Hr24, and Hr72 following injection of either lipopolysaccharide or phosphate buffered saline. Neural FC strength decreased at Hr8 and returned to baseline by Hr72 in motor, somatosensory, parietal, and visual cortical regions. Additionally, neural fluctuations transiently declined at Hr8 and returned to baseline by Hr72. Both FC strength and fluctuation tone correlated with neuroscore indicating this imaging methodology is a sensitive and acute readout of encephalopathy.

Transdermal Transmission Blocking Vaccine for Malaria using a Solid-in-Oil Dispersion

Malaria is a mosquito-borne infectious disease that is widespread in developing countries. Malaria vaccines are important in efforts to eradicate malaria; however, vaccines are usually administered by injection, which requires medical personnel and has a risk of causing infection. Transdermal vaccines can be administered without damaging the skin and thus are ideal for the prevention of malaria. However, the stratum corneum forms a "brick and mortar" like structure in which stratum corneum cells are embedded in a hydrophobic matrix composed of lipids, which strongly inhibits the permeation of hydrophilic substances. In the present study, we designed a transdermal vaccine against vivax malaria using a solid-in-oil (S/O) dispersion. The S/O dispersion of a transmission blocking vaccine candidate, Pvs25 from Plasmodium vivax, showed higher skin penetration than that of the aqueous solution. Mice immunized with the S/O dispersion generated antibodies at similar titers as the mice immunized by injection, over the mid- to long-term. These results provide information for the development of transdermally administered malaria vaccines toward the eradication of malaria.

High yield production of norovirus GII.4 virus-like particles using silkworm pupae and evaluation of their protective immunogenicity

Noroviruses (NoVs) are one of the major causes of acute viral gastroenteritis in humans. Virus-like particles (VLPs) without genomes that mimic the capsid structure of viruses are promising vaccine candidates for the prevention of NoVs infection. To produce large amounts of recombinant protein, including VLPs, the silkworm-expression vector system (silkworm-BEVS) is an efficient and powerful tool. In this study, we constructed a recombinant baculovirus that expresses VP1 protein, the major structural protein of NoV GII.4. Expression analysis showed that the baculovirus-infected silkworm pupae expressed NoV VP1 protein more efficiently than silkworm larval fat bodies. We obtained about 4.9 mg of purified NoV VP1 protein from only five silkworm pupae. The purified VP1 protein was confirmed by dynamic light scattering and electron microscopy to form VLPs of approximately 40 nm in diameter. Antisera from mice immunized with the antigen blocked NoV VLPs binding to histo-blood group antigens of pig gastric mucin and also blocked NoV infection in intestinal epithelial cells derived from human induced pluripotent stem (iPS) cells. Our findings demonstrated that NoV VLP eliciting protective antibodies could be obtained in milligram quantities from a few silkworm pupae using the silkworm-BEVS.

SARS-CoV-2 strain-specific anti-spike IgG ELISA utilizing spike protein produced by silkworms

BACKGROUND

A cost-effective and eco-friendly method is needed for the assessment of humoral immunity against SARS-CoV-2 in large populations.

OBJECTIVE

We investigated the performance of an ELISA that uses silkworm-produced proteins to quantify the strain-specific anti-Spike IgG (anti-S IgG) titer.

METHODS

The OD values for the anti-His-tag antibody, a standard material of ELISA quantification, were measured. Correlations between the ELISA for each strain and the Abbott SARS-CoV-2 IgG II Quant assay for the wild type were evaluated with serum samples from nine participants with various infection and vaccination statuses.

RESULTS

Linear dose-responses were confirmed by high coefficients of determination: 0.994, 0.994, and 0.996 for the wild-type, Delta, and Omicron (BA.1) strain assays, respectively. The coefficient of determination for the wild-type and Delta strain assays was high at 0.959 and 0.892, respectively, while the Omicron strain assay had a relatively low value of 0.563. Booster vaccinees showed similar or higher titers against all strains compared to infected persons without vaccination. The Omicron-infected persons without vaccination had lower antibody titers against wild type than did the vaccinated persons.

CONCLUSIONS

This study provides data indicating that the ELISA with silkworm-produced proteins makes it possible to discriminate and quantify the strain-specific anti-S IgG antibody induced by vaccination or infection.

TRPC3-Nox2 Protein Complex Formation Increases the Risk of SARS-CoV-2 Spike Protein-Induced Cardiomyocyte Dysfunction through ACE2 Upregulation

Myocardial damage caused by the newly emerged coronavirus (SARS-CoV-2) infection is one of the key determinants of COVID-19 severity and mortality. SARS-CoV-2 entry to host cells is initiated by binding with its receptor, angiotensin-converting enzyme (ACE) 2, and the ACE2 abundance is thought to reflect the susceptibility to infection. Here, we report that ibudilast, which we previously identified as a potent inhibitor of protein complex between transient receptor potential canonical (TRPC) 3 and NADPH oxidase (Nox) 2, attenuates the SARS-CoV-2 spike glycoprotein pseudovirus-evoked contractile and metabolic dysfunctions of neonatal rat cardiomyocytes (NRCMs). Epidemiologically reported risk factors of severe COVID-19, including cigarette sidestream smoke (CSS) and anti-cancer drug treatment, commonly upregulate ACE2 expression level, and these were suppressed by inhibiting TRPC3-Nox2 complex formation. Exposure of NRCMs to SARS-CoV-2 pseudovirus, as well as CSS and doxorubicin (Dox), induces ATP release through pannexin-1 hemi-channels, and this ATP release potentiates pseudovirus entry to NRCMs and human iPS cell-derived cardiomyocytes (hiPS-CMs). As the pseudovirus entry followed by production of reactive oxygen species was attenuated by inhibiting TRPC3-Nox2 complex in hiPS-CMs, we suggest that TRPC3-Nox2 complex formation triggered by panexin1-mediated ATP release participates in exacerbation of myocardial damage by amplifying ACE2-dependent SARS-CoV-2 entry.

Construction of gene co-expression networks in cultured silkworm cells and identification of previously uncharacterized lepidopteran-specific genes required for chromosome dynamics

Advances in sequencing technology and bioinformatics have accelerated gene discovery and homology-based functional annotation in many species, and numerous targeted gene studies have greatly expanded the understanding of gene functions. Nevertheless, there are still many genes that lack homology with genes in other evolutionary lineages and are left as genes with unknown functions. We constructed a gene co-expression network from the Bombyx mori ovary-derived cell line, BmN4, and attempted to infer the biological roles of uncharacterized genes based on the correlation between the function-known and unknown genes. Within this network, we focused on the co-expression modules involved in chromosome architecture, dynamics, and integrity, and selected the uncharacterized genes for subsequent RNAi-based phenotypic screening. This approach enabled the identification of 5 genes whose knockdown led to abnormalities in chromosome dynamics and spindle morphology in mitosis. One of them was a recently characterized gene, BmCenp-T, which plays a central role in building the kinetochore protein complex on the silkworm holocentric chromosomes. In this study, we suggest a method for constructing the gene co-expression network and selecting candidate genes for small-scale RNAi screening. This approach is complementary to homology-based annotation and may be useful for the analysis of lineage-specific uncharacterized genes such as orphan genes.

Sex-differences in prevalence and outcomes of the different endotypes of chronic coronary syndrome – analysis from the multi-center international ILIAS Registry

Introduction

Guideline-directed management of chronic coronary syndrome (CCS) remains focused on obstructive causes of angina, and is based on established therapies derived from studies predominantly including men. This occurs despite documented higher mortality from cardiovascular causes in women compared to men, which is hypothesized to be related to a higher prevalence of coronary microvascular dysfunction (CMD) in women. However, data on the relationship between sex, the different endotypes of CCS, and related sex-specific clinical outcomes are limited.

Purpose

This study aimed to investigate the relationship between sex and the different endotypes of CCS, as well as sex-specific clinical outcomes of CCS endotypes.

Method

In patients with stable angina undergoing coronary angiography, the following invasive coronary hemodynamics were characterized: fractional flow reserve (FFR; <0.80 considered abnormal), coronary flow reserve (CFR; <2.0 considered abnormal) and microcirculatory resistance (MR) (hyperemic microvascular resistance; >2.5mmHg/cm/sec or index of microvascular resistance >25 considered abnormal). Patients were stratified into three groups: 1) hemodynamically significant obstructive coronary artery disease (oCAD) (FFR abnormal or a severe coronary stenosis requiring revascularization), 2) no-obstructive coronary artery disease but with CMD (FFR normal, but abnormal CFR and/or MR), or 3) no-obstructive coronary artery disease and no CMD (FFR normal, and normal CFR and MR). We assessed the prevalence of the CCS endotypes across sex, and sex-specific cardiovascular outcomes over a follow-up of 7 years defined as the composite endpoint of death or acute myocardial infarction.

Results

Amongst a total of 1987 included patients, 1435 (72.2%) were men and 552 (27.8%) were women. oCAD occurred in 904 (45.5%) patients, which was significantly more prevalent in men (48.9% (701/1435) of men vs. 36.8% (203/552) of women, p<0.001). In contrast, CMD was significantly more prevalent in women (19.6% (281/1435) of men vs. 24.1% (133/552) of women, p=0.031). Across the population, either oCAD or CMD occurred in 68.4% of men versus 60.9% of women (p=0.002). There were no sex-specific differences in cardiovascular outcomes across CCS entities (Figure 1).

Conclusion

In patients evaluated for CCS who underwent clinically indicated coronary angiography and physiological assessment, men were more likely to have oCAD and women were more likely to be classified as CMD. There were no sex-related differences in the prognosis associated with the individual CCS endotypes. Therefore, pathophysiological changes in the coronary circulation potentially underlying angina pectoris are similarly prevalent in men and women, but the high incidence of CMD in women makes women prone to underdiagnosis if no additional physiological measurements are assessed.

Funding Acknowledgement

Type of funding sources: None.

Hyperaemic and non-hyperaemic pressure indices of coronary stenosis severity in patients with chronic kidney disease

Background

Evidence regarding the use of pressure indices for the assessment of coronary stenoses in patients with chronic kidney disease (CKD) is scarce.

Methods

We assessed the relation between eGFR, FFR and resting Pd/Pa in 1147 consecutive patients (1316 vessels) included in the International Collaboration of Comprehensive Physiologic Assessment Study. We also compared FFR and Pd/Pa against a standardized cut-off of coronary flow reserve (CFR<2.0). Finally, we examined the occurrence of vessel-oriented composite outcome (VOCO: cardiac death, vessel-specific revascularization, vessel-specific myocardial infarction) across negative/positive results of both FFR and CFR in patients with and without CKD.

Results

FFR increases as renal function worsens (beta −10.5, 95% CI −20.0 to −11.03, p=0.030), a relation that was not seen with resting Pd/Pa (beta −6.14, 95% CI −19.9 to 6.78, p=0.351). Both indices had similar diagnostic accuracies for the detection of a CFR<2.0 in the presence of CKD (AUC 0.629 for FFR vs 0.663 for resting Pd/Pa, p=0.192). However, CKD patients showed a higher proportion of vessels with negative FFR but low CFR (24.5% vs 13.4%, p=0.015).

CFR decreased linearly with deteriorating eGFR, and this was mainly driven by higher resting coronary flow in CKD patients (p=0.026), while hyperaemic coronary flow remained similar (p=0.403). IMR did not change significantly with eGFR (beta −0.02, 95% −0.09 to 0.05, p=0.557).

The incidence of VOCO was higher in patients with CKD and FFR>0.80 when compared to non-CKD patients and FFR>0.80 (12.7% vs 6.90%, p=0.062). Prognosis was worse for those with CKD, negative FFR and CFR<2.0 (20.59% vs. 8.44% in non-CKD, p=0.038).

Conclusions

The assessment of a given coronary stenosis in patients with CKD with either FFR or resting Pd/Pa is equivalent when compared to underlying coronary flow. In CKD, impaired CFR is caused by a state of increased resting flow. The assessment of CFR on top of standard pressure wire examination significantly improves prognostic stratification in CKD patients.

Funding Acknowledgement

Type of funding sources: None.

Impact of obesity paradox between genders on in-hospital mortality in cardiogenic shock: a retrospective cohort study

Background

In a few studies, obesity was associated with better outcomes in patients with cardiogenic shock (CS). Although this phenomenon, the “obesity paradox”, reportedly manifests differently based on sex in other disease entities, it has not yet been investigated in CS patients.

Methods and results

1,227 patients with CS from The REtrospective and prospective observational Study to investigate Clinical oUtcomes and Efficacy of left ventricular assist device for Korean patients with cardiogenic shock (RESCUE) registry in Korea were analyzed. The study population was classified into obese and non-obese groups according to Asian-Pacific criteria (BMI >25.0 kg/m2 for obese). Clinical impact of obesity on in-hospital mortality according to sex was analyzed using logistic regression analysis and restricted cubic spline curves. In-hospital mortality rate was significantly lower in obese men than non-obese men (34.2% vs. 24.1%, p=0.004) while the difference was not significant in women (37.3% vs. 35.8%, p=0.884). As a continuous variable, higher BMI showed a protective effect in men conversely, BMI was not associated with clinical outcomes in women. Comparing to normal-weight patients, obesity was associated with a decreased risk of in-hospital death in men (multivariable-adjusted OR 0.63, CI 0.43–0.92, p=0.016), not in women (multivariable-adjusted OR 0.94, 95% CI 0.55–1.61, p=0.828). Interaction P value for the association between BMI and sex was 0.023.

Conclusions

Obesity paradox exists and apparently occurs in men among CS patients. The differential effect of BMI on in-hospital mortality was observed according to sex.

Funding Acknowledgement

Type of funding sources: None.

Sodium-glucose co-transporter-2 inhibitors after acute myocardial infarction in type 2 diabetes patients: a population-based investigation from South Korea

Background

Whether the early use of sodium-glucose co-transporter-2 (SGLT2) inhibitors has cardioprotective effects following acute myocardial infarction (AMI) is unknown.

Purpose

We aimed to evaluate the association between the early initiation of SGLT2 inhibitors and cardiac event rates in diabetes patients with AMI undergoing percutaneous coronary intervention (PCI).

Methods

Based on the National Health Insurance claims data in South Korea, patients aged 18 years or older who had undergone PCI for the diagnosis of AMI between 2014 and 2018 were analyzed. Patients treated with SGLT2 inhibitors or other glucose-lowering drugs were matched based on a propensity score. The primary endpoint was a composite of all-cause mortality and hospitalizations for heart failure (HF). Major adverse cardiac events (MACE; a composite of all-cause death, non-fatal MI, and ischemic stroke) were compared as the secondary endpoint.

Results

After 1:2 propensity score matching, a total of 26,814 patients were assigned to the SGLT2 inhibitors group (938 patients) and the no use of SGLT2 inhibitors group (1,876 patients), respectively. During a median follow-up of 2.1 years, compared to no use of SGLT2 inhibitors, the early use of SGLT2 inhibitors was associated with lower risks of both the primary endpoint (9.8% vs. 13.9%, adjusted hazard ratio [HR] = 0.68, 95% confidence interval [CI]: 0.54 to 0.87, p=0.002) and secondary endpoint (9.1% vs. 11.6%, adjusted HR = 0.77, 95% CI: 0.60 to 0.99, p=0.04) (Figure 1). All-cause mortality and hospitalizations for HF were significantly lower in the early use of SLGT2 inhibitors group (adjusted HR = 0.55; 95% CI: 0.37 to 0.80; p=0.002; and HR = 0.74; 95% CI: 0.56 to 0.98; p=0.03, respectively). The incidence of non-fatal MI and ischemic stroke were not statistically different (Figure 2).

Conclusions

The early use of SGLT2 inhibitors in diabetes patients treated with PCI for AMI was associated with a significantly lower risk of cardiovascular events including all-cause mortality, hospitalizations for HF, and MACE. Our results suggest that the use of SGLT2 inhibitors could expand to the acute phase of AMI survivors with diabetes to reduce mortality and the subsequent development of congestive HF and ischemic events.

Funding Acknowledgement

Type of funding sources: Private hospital(s). Main funding source(s): This work was partly supported by the Research Institute of Medical Science, The Catholic University of Korea, Eunpyeong St. Mary's Hospital, Seoul, Republic of Korea.

Atypical periprosthetic femoral fracture with stem breakage: a case report

Although the American Society for Bone and Mineral Research definition of atypical femoral fracture excludes periprosthetic fractures, fractures around the prosthesis with clinical features of atypical femoral fractures have been reported in the literature. All fractures reported thus far have been distal to the prosthetic segment; however, we encountered a case of a stress fracture in the middle of the femoral component segment. An 86-year-old woman with a history of bisphosphonate osteoporosis treatment and revisional total hip arthroplasty visited our outpatient clinic complaining of pain in the left thigh and groin. We diagnosed an incomplete atypical femoral fracture around the hip prosthesis; medical treatment was implemented. Two months later, the patient visited the emergency department with a complete subtrochanteric fracture with stem breakage. Without revision of the broken stem, two plates were applied after reduction. In this case, we recognized the possibility of a stress fracture but overlooked the possibility of stem breakage in an atypical femoral fracture. Even if it is not evident on the radiograph before complete fracture, clinicians should be alert to the signs of stress fracture in the middle of the femoral component segment, as they may be clues to atypical periprosthetic femoral fracture with stem failure. Isolated medical treatment plans are not recommended for incomplete subtrochanteric atypical periprosthetic femoral fracture. Instead, concomitant prophylactic plate fixation is recommended.

Silkworm FoxL21 plays important roles as a regulator of ovarian development in both oogenesis and ovariole development

The ovary is an important organ in reproduction. In insects, especially lepidopteran insects, the oocytes and reproductive organs develop rapidly during the pupal stage. Despite their drastic morphological changes, the molecular mechanisms of ovary development are not fully understood. In this study, it is found that forkhead box transcription factor L2, member 1 (FoxL21), which is known to be involved in ovarian differentiation and maintenance in vertebrates, is required for the development of the ovary in the silkworm, Bombyx mori. FoxL21 was expressed in the ovary and ovariole during the larval and pupal stage, respectively. In silkworms in which FoxL21 was knocked out by genome editing, multiple ovarian dysfunctions, such as, abnormal egg formation, thinning of the ovariole sheaths, and defective connection of the oviductus geminus with the ovariole were observed. Finally, ovarian transplantation experiments using the knockout silkworms revealed that FoxL21 functions in the ovariole, but not in the oviductus geminus.

NRF2 Activation in Autophagy Defects Suppresses a Pharmacological Transactivation of the Nuclear Receptor FXR

NF-E2-related factor 2 (NRF2), an antioxidant transcription factor, is activated in autophagy-deficient mice due to the accumulations of p62/SQSTM1 and its subsequent interaction with Kelch-like-ECH-associated protein 1 (KEAP1), an adaptor component for Cullin3-based E3 ubiquitin ligase complex. Farnesoid x receptor (FXR/NR1H4) is a ligand-dependent transcription factor that belongs to the nuclear receptor superfamily. FXR plays an essential role in bile acid synthesis and enterohepatic circulation, affecting glucose and lipid metabolism. Obeticholic acid as a potent FXR agonist has been approved to treat primary biliary cholangitis and clinical trials for its use in the treatment of other liver diseases are underway. Here we show that NRF2 activation in autophagy defects impedes a transactivation of FXR. Liver-specific Atg7 knockout mice or a treatment of autophagy inhibitor showed decreased inductions of FXR target genes upon its synthetic agonists. Moreover, enforced NRF2 activations with small molecules potently decreased the pharmacological activation of FXR in cultured cells. Finally, we demonstrate that NRF2 activation by the treatment with the food antioxidant butylated hydroxyanisole is necessary and sufficient to inhibit the pharmacological activation of FXR in vivo. These results reveal a novel function of the basal autophagy-NRF2 axis for the regulation of FXR transactivation, and shed light on a potential therapeutic strategy in metabolic disease.

Transcriptional Control of Trpm6 by the Nuclear Receptor FXR

Farnesoid x receptor (FXR) is a nuclear bile acid receptor that belongs to the nuclear receptor superfamily. It plays an essential role in bile acid biosynthesis, lipid and glucose metabolism, liver regeneration, and vertical sleeve gastrectomy. A loss of the FXR gene or dysregulations of FXR-mediated gene expression are associated with the development of progressive familial intrahepatic cholestasis, tumorigenesis, inflammation, and diabetes mellitus. Magnesium ion (Mg²⁺) is essential for mammalian physiology. Over 600 enzymes are dependent on Mg²⁺ for their activity. Here, we show that the Trpm6 gene encoding a Mg²⁺ channel is a direct FXR target gene in the intestinal epithelial cells of mice. FXR expressed in the intestinal epithelial cells is absolutely required for sustaining a basal expression of intestinal Trpm6 that can be robustly induced by the treatment of GW4064, a synthetic FXR agonist. Analysis of FXR ChIP-seq data revealed that intron regions of Trpm6 contain two prominent FXR binding peaks. Among them, the proximal peak from the transcription start site contains a functional inverted repeat 1 (IR1) response element that directly binds to the FXR-RXRα heterodimer. Based on these results, we proposed that an intestinal FXR-TRPM6 axis may link a bile acid signaling to Mg²⁺ homeostasis.

Optimization of SARS-CoV-2 Spike Protein Expression in the Silkworm and Induction of Efficient Protective Immunity by Inoculation With Alum Adjuvants

The newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is causing a spread of coronavirus disease 2019 (COVID-19) globally. In order to end the COVID-19 pandemic, an effective vaccine against SARS-CoV-2 must be produced at low cost and disseminated worldwide. The spike (S) protein of coronaviruses plays a pivotal role in the infection to host cells. Therefore, targeting the S protein is one of the most rational approaches in developing vaccines and therapeutic agents. In this study, we optimized the expression of secreted trimerized S protein of SARS-CoV-2 using a silkworm-baculovirus expression vector system and evaluated its immunogenicity in mice. The results showed that the S protein forming the trimeric structure was the most stable when the chicken cartilage matrix protein was used as the trimeric motif and could be purified in large amounts from the serum of silkworm larvae. The purified S protein efficiently induced antigen-specific antibodies in mouse serum without adjuvant, but its ability to induce neutralizing antibodies was low. After examining several adjuvants, the use of Alum adjuvant was the most effective in inducing strong neutralizing antibody induction. We also examined the adjuvant effect of paramylon from Euglena gracilis when administered with the S protein. Our results highlight the effectiveness and suitable construct design of the S protein produced in silkworms for the subunit vaccine development against SARS-CoV-2.

Production of scFv, Fab, and IgG of CR3022 Antibodies Against SARS-CoV-2 Using Silkworm-Baculovirus Expression System

COVID-19, caused by SARS-CoV-2, is currently spreading around the world and causing many casualties. Antibodies against such emerging infectious diseases are one of the important tools for basic viral research and the development of diagnostic and therapeutic agents. CR3022 is a monoclonal antibody against the receptor binding domain (RBD) of the spike protein (S protein) of SARS-CoV found in SARS patients, but it was also shown to have strong affinity for that of SARS-CoV-2. In this study, we produced large amounts of three formats of CR3022 antibodies (scFv, Fab and IgG) with high purity using a silkworm-baculovirus expression vector system. Furthermore, SPR measurements showed that the affinity of those silkworm-produced IgG antibodies to S protein was almost the same as that produced in mammalian expression system. These results indicate that the silkworm-baculovirus expression system is an excellent expression system for emerging infectious diseases that require urgent demand for diagnostic agents and therapeutic agents.

Standardization of 129I using the movable 4πβ(LS)-X(NaI(Tl)) system

The ¹²⁹I standardization, using the movable 4πβ(LS)-X(NaI(Tl)) coincidence system, was performed for two ¹²⁹I radioactive sources - one was dissolved in 0.1M NaOH solution and the other in 0.1M HNO₃ solution. The system incorporates three movable PM tubes for a β-counter placed on a plane and a X-ray detector that can be moved up to the bottom of the vial. The β-efficiency depending on the amount of radioactive solution was investigated with 14 liquid scintillation samples prepared by gravimetrically dispensing 4.4-145 mg of ¹²⁹I radioactive solution. The β-efficiencies above 90% were observed at less than 56 mg, but it was at most 70% at 145 mg. This occurred regardless of the activity of the sample or the type of chemical solution used to dissolve ¹²⁹I source. The activity concentration of each ¹²⁹I source was determined by efficiency-extrapolation method for samples with an activity range of 0.28-4.5 kBq. The β-efficiency points were derived over 10 intervals by moving 3-PM tubes in fine steps of about 1 mm from the sample. The highest value for β-efficiency was 95%. The combined uncertainty were 0.25% and 0.26%, respectively. The stated precision obtained using the system is better than that previously reported in the literature obtained by the triple to double coincidence ratio (TDCR) or the CIEMAT/NIST efficiency tracing method.

Non-molting dwarf (nm-d) as a mutant of Bombyx mori with a defect in purine synthesis

There are several known non-molting mutations of the silkworm, Bombyx mori, including non-molting dwarf (nm-d). Larvae with this mutation hatch normally and start eating leaves, but die before the completion of the first ecdysis. Genetic analysis of the nm-d mutation would contribute to the isolation of essential genes for the larval development of lepidopteran insects. To identify the causative gene of the nm-d locus, we conducted RNA-seq based rough mapping. Using two sets of RNA-seq data, one from a pooled sample of normal larvae, and one from a pooled sample of nm-d larvae, the nm-d locus was narrowed to a 500 kb region. Among the genes located in this region, a nm-d-specific exon loss was identified in the Bombyx homolog of the ATIC (5-aminoimidazole-4-carboxamide ribonucleotide transformylase/Inosine 5'-monophosphate cyclohydrolase) (BmATIC) gene, which catalyzes the final two steps of the de novo purine biosynthetic pathway in mammals. PCR and subsequent sequencing analysis revealed that a region containing exon 9 of the BmATIC gene is deleted in the nm-d larvae. A knockout allele of the BmATIC gene (BmATIC^KO), that was generated using the CRISPR/Cas9 system, revealed that first instar knockout larvae died while exhibiting the dark brown larval body that is a typical feature of mutants that lack uric acid in the integument. Lethal larvae resulted from crosses between +/BmATIC^KO moths. The uric acid content in the whole-body of the first instar was drastically reduced in the nm-d larvae compared to normal larvae. These results indicated that the BmATIC gene is responsible for the nm-d phenotype, and that nm-d larvae have a defect in purine biosynthesis, including uric acid. We also discuss the possibility that the BmATIC mRNA is maternally transmitted to eggs. Our results indicated that RNA-seq based mapping using pooled samples is a practical method for the identification of the causative genes of lethal mutations.

Retrograde transvenous obliteration for the prevention of variceal rebleeding in patients with hepatocellular carcinoma: a multicentre retrospective study

AIM

To evaluate the effectiveness and safety of retrograde transvenous obliteration (RTO) for the prevention of variceal rebleeding variceal rebleeding in patients with hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

This multicentre retrospective study enrolled 79 patients with HCC who underwent RTO for the prevention of variceal rebleeding. Successful occlusion of the gastrorenal shunt and obliteration of the gastric varices were achieved in 74 patients, with a technical success rate of 93.7%. Of the remaining 74 patients (mean age, 64.9±10.3 years; 56 men), 66 (90.4%) had gastroesophageal varices and seven (9.6%) had isolated gastric varices. Thirty-two patients (43.8%) underwent balloon-occluded RTO, 40 patients (54.8%) underwent plug-assisted RTO, and one patient (1.4%) underwent coil-assisted RTO. No patients had major procedural complications.

RESULTS

Rebleeding occurred in seven patients (9.6%) during the follow-up period. The 6-week and 1-year actuarial probabilities of patients remaining free of rebleeding were 90.8±3.6% and 88.6±4.1%, respectively. The median survival was 12.6 (95% confidence interval [CI] 8-17.3) months. The 6-week, 1-year, and 3-year actuarial probabilities of survival were 83.2±4.4%, 51.1±6.6%, and 32.7±7%, respectively. New or worsening ascites and oesophageal varices occurred in 12 (16.4%) and 13 patients (17.8%), respectively, during the follow-up period. Overt hepatic encephalopathy occurred in one patient (1.4%) during the follow-up period. The Child-Pugh score remained comparable to that at baseline at 1 and 3 months.

CONCLUSION

RTO was effective and safe in preventing variceal rebleeding in patients with HCC.

Mitophagy deficiency increases NLRP3 to induce brown fat dysfunction in mice

Although macroautophagy/autophagy deficiency causes degenerative diseases, the deletion of essential autophagy genes in adipocytes paradoxically reduces body weight. Brown adipose tissue (BAT) plays an important role in body weight regulation and metabolic control. However, the key cellular mechanisms that maintain BAT function remain poorly understood. in this study, we showed that global or brown adipocyte-specific deletion of pink1, a Parkinson disease-related gene involved in selective mitochondrial autophagy (mitophagy), induced BAT dysfunction, and obesity-prone type in mice. Defective mitochondrial function is among the upstream signals that activate the NLRP3 inflammasome. NLRP3 was induced in brown adipocyte precursors (BAPs) from pink1 knockout (KO) mice. Unexpectedly, NLRP3 induction did not induce canonical inflammasome activity. Instead, NLRP3 induction led to the differentiation of pink1 KO BAPs into white-like adipocytes by increasing the expression of white adipocyte-specific genes and repressing the expression of brown adipocyte-specific genes. nlrp3 deletion in pink1 knockout mice reversed BAT dysfunction. Conversely, adipose tissue-specific atg7 KO mice showed significantly lower expression of Nlrp3 in their BAT. Overall, our data suggest that the role of mitophagy is different from general autophagy in regulating adipose tissue and whole-body energy metabolism. Our results uncovered a new mitochondria-NLRP3 pathway that induces BAT dysfunction. The ability of the nlrp3 knockouts to rescue BAT dysfunction suggests the transcriptional function of NLRP3 as an unexpected, but a quite specific therapeutic target for obesity-related metabolic diseases.Abbreviations: ACTB: actin, beta; BAPs: brown adipocyte precursors; BAT: brown adipose tissue; BMDMs: bone marrow-derived macrophages; CASP1: caspase 1; CEBPA: CCAAT/enhancer binding protein (C/EBP), alpha; ChIP: chromatin immunoprecipitation; EE: energy expenditure; HFD: high-fat diet; IL1B: interleukin 1 beta; ITT: insulin tolerance test; KO: knockout; LPS: lipopolysaccharide; NLRP3: NLR family, pyrin domain containing 3; PINK1: PTEN induced putative kinase 1; PRKN: parkin RBR E3 ubiquitin protein ligase; RD: regular diet; ROS: reactive oxygen species; RT: room temperature; UCP1: uncoupling protein 1 (mitochondrial, proton carrier); WT: wild-type.

Development of a movable 4πβ(LS)-γ coincidence counting system for activity standardization of β-γ emitters

A new movable 3PM-γ coincidence system, based on 4πβ(LS)-γ coincidence counting, for activity measurement of β-γ emitters has been designed at the Korea Research Institute of Standards and Science (KRISS). The system incorporates 3 PM tubes on the plane and two detectors placed above and below the center of the plane. The 3 PM tubes for β-counters in the plane are movable up to 100 mm from a liquid scintillation vial, thus enabling the variation of β-detection efficiencies by a geometrical technique. A NaI(Tl) γ-counter was set above for the present work. The β-event is determined by counting the logical sum of three double coincidences. All the necessary electronics, i.e., logical sum, adjusting the duration of dead-time of each counting channel and coincidence resolving times, and analyzing coincidence relation, were specially designed to be fabricated in an integrated circuit. Details of the detectors, the electronics, the overall movable 3PM-γ coincidence system are presented, as well as the results of investigations to assess its operating characteristics. Validation measurements have been performed with ⁶⁰Co and ⁵⁷Co sources. The highest β-detection efficiency achieved with ⁶⁰Co and ⁵⁷Co was 97% and 95%, respectively. The activity concentration determined with a new system agreed with calibrated values within the uncertainty range. Further results from validation measurements and the corresponding uncertainty budgets are presented.

Quick and Easy Assembly of a One-Step qRT-PCR Kit for COVID-19 Diagnostics Using In-House Enzymes

One-step reverse-transcription quantitative polymerase chain reaction (qRT-PCR) is the most widely applied method for COVID-19 diagnostics. Notwithstanding the facts that one-step qRT-PCR is well suited for the diagnosis of COVID-19 and that there are many commercially available one-step qRT-PCR kits in the market, their high cost and unavailability due to airport closures and shipment restriction became a major bottleneck that had driven the desire to produce the key components of such kits locally. Here, we provide a simple, economical, and powerful one-step qRT-PCR kit based on patent-free, specifically tailored versions of Moloney murine leukemia virus reverse transcriptase and Thermus aquaticus DNA polymerase and termed R3T (Rapid Research Response Team) one-step qRT-PCR. We also demonstrate the robustness of our enzyme production strategies and provide the optimal reaction conditions for their efficient augmentation in a one-step approach. Our kit was routinely able to reliably detect as low as 10 copies of the synthetic RNAs of SARS-CoV-2. More importantly, our kit successfully detected COVID-19 in clinical samples of broad viral titers with similar reliability and selectivity to that of the Invitrogen SuperScript III Platinum One-step qRT-PCR and TaqPath one-step RT-qPCR kits. Overall, our kit has shown robust performance in both laboratory settings and the Saudi Ministry of Health-approved testing facility.

Current Understanding on the Metabolism of Neutrophils

Neutrophils are innate immune cells that constitute the first line of defense against invading pathogens. Due to this characteristic, they are exposed to diverse immunological environments wherein sources for nutrients are often limited. Recent advances in the field of immunometabolism revealed that neutrophils utilize diverse metabolic pathways in response to immunological challenges. In particular, neutrophils adopt specific metabolic pathways for modulating their effector functions in contrast to other immune cells, which undergo metabolic reprogramming to ensure differentiation into distinct cell subtypes. Therefore, neutrophils utilize different metabolic pathways not only to fulfill their energy requirements, but also to support specialized effector functions, such as neutrophil extracellular trap formation, ROS generation, chemotaxis, and degranulation. In this review, we discuss the basic metabolic pathways used by neutrophils and how these metabolic alterations play a critical role in their effector functions.

Autophagy in neutrophils

Autophagy is a highly conserved intracellular degradation and energy-recycling mechanism that contributes to the maintenance of cellular homeostasis. Extensive researches over the past decades have defined the role of autophagy innate immune cells. In this review, we describe the current state of knowledge regarding the role of autophagy in neutrophil biology and a picture of molecular mechanism underlying autophagy in neutrophils. Neutrophils are professional phagocytes that comprise the first line of defense against pathogen. Autophagy machineries are highly conserved in neutrophils. Autophagy is not only involved in generalized function of neutrophils such as differentiation in bone marrow but also plays crucial role effector functions of neutrophils such as granule formation, degranulation, neutrophil extracellular traps release, cytokine production, bactericidal activity and controlling inflammation. This review outlines the current understanding of autophagy in neutrophils and provides insight towards identification of novel therapeutics targeting autophagy in neutrophils.

A defect in purine nucleotide metabolism in the silkworm, Bombyx mori, causes a translucent larval integument and male infertility

p-oily (op) is a novel mutant of Bombyx mori exhibiting translucent larval integument and male infertility. Elucidation of the causative gene of the op mutant will help understand the genetic mechanism underlying larval integument coloration and male fertility. Using polymorphisms between B. mori and B. mandarina, the op locus was narrowed down to a 375-kb region. Using RNA-seq analysis, we found that op mutants have a frameshift mutation in the KWMTBOMO13770 gene located in the 375-kb region. A database search indicated that this gene is the human cytosolic 5'-nucleotidase II gene (cN-II) homolog in Bombyx, which mediates the conversion of inosine monophosphate (IMP) to inosine, a precursor of uric acid. CRISPR/Cas9-mediated knockout mutants of the Bm-cN-II gene showed translucent integuments, and there appeared translucent larvae in the crosses between knockout moths and +/op moths. Moreover, the translucent phenotype of, and decreased uric acid content in the larval integument caused by the mutations in the Bm-cN-II gene were rescued by oral administration of inosine. These results indicated that the Bm-cN-II gene is responsible for the op phenotype and that the molecular function of the Bm-cN-II gene is the conversion of IMP to inosine. We also discuss the genetic relationship between the Bm-cN-II gene and male fertility.

Strong correlation between flux pinning and epitaxial strain in the GdBa2Cu3O7-x /La0.7Sr0.3MnO3 nanocrystalline heterostructure

The effect of magnetic flux pinning is investigated in GdBa₂Cu₃O₇ (GdBCO) thin films with two different types of ferromagnetic La_0.7Sr_0.3MnO₃ (LSMO) buffers (nanoparticles and a layer) deposited on an STO substrate. Magnetization analyses reveal the presence of multiple flux pinning mechanisms responsible for the improvement in the critical current density of GdBCO films. While core pinning becomes a dominant pinning mechanism in GdBCO films with LSMO nanoparticles, a hybrid effect of magnetic-volume and core-point pinning is observed in GdBCO films with LSMO layers. Examinations of local structures for both LSMO and GdBCO using extended X-ray absorption fine structure spectroscopy (EXAFS) exhibit a close relation between the parameters in the pinning force scaling and the length ratio of the Mn–O bond to the Cu–O bond. This result implies that the origin of core pinning is probably attributed to epitaxial strain induced by lattice mismatch between LSMO and GdBCO. Therefore, an appropriate strain state of LSMO is required for an effective operation of magnetic pinning.

The effect of magnetic flux pinning is investigated in GdBa₂Cu₃O₇ (GdBCO) thin films with two different types of ferromagnetic La_0.7Sr_0.3MnO₃ (LSMO) buffers (nanoparticles and a layer) deposited on an STO substrate.

Using Eukaryotic Expression Systems to Generate Human α1,3-Fucosyltransferases That Effectively Create Selectin-Binding Glycans on Stem Cells

Recruitment of circulating cells toward target sites is primarily dependent on selectin/ligand adhesive interactions. Glycosyltransferases are involved in the creation of selectin ligands on proteins and lipids. α1,3-Fucosylation is imperative for the creation of selectin ligands, and a number of fucosyltransferases (FTs) can modify terminal lactosamines on cells to create these ligands. One FT, fucosyltransferase VI (FTVI), adds a fucose in an α1,3 configuration to N-acetylglucosamine to generate sialyl Lewis X (sLe^x) epitopes on proteins of live cells and enhances their ability to bind E-selectin. Although a number of recombinant human FTVIs have been purified, apart from limited commercial enzymes, they were not characterized for their activity on live cells. Here we focused on establishing a robust method for producing FTVI that is active on living cells (hematopoietic cells and mesenchymal stromal cells). To this end, we used two expression systems, Bombyx mori (silkworm) and Pichia pastoris (yeast), to produce significant amounts of N-terminally tagged FTVI and demonstrated that these enzymes have superior activity when compared to currently available commercial enzymes that are produced from various expression systems. Overall, we outline a scheme for obtaining large amounts of highly active FTVI that can be used for the application of FTVI in enhancing the engraftment of cells lacking the sLe^x epitopes.

The alternative complement pathway in ANCA-associated vasculitis: further evidence and a meta-analysis

We compared the common pathway components C3a, C5a and membrane attack complex (MAC), also known as C5b-9, and the alternative pathway components factor B and properdin in patients with ANCA-associated vasculitis (AAV) and healthy controls, and conducted a meta-analysis of the available clinical evidence for the role of complement activation in the pathogenesis of AAV. Complement components were evaluated in 59 patients with newly diagnosed or relapsing granulomatosis with polyangiitis or microscopic polyangiitis and 36 healthy volunteers. In 28 patients, testing was repeated in remission. Next, we performed a meta-analysis by searching databases to identify studies comparing complement levels in AAV patients and controls. A random-effects model was used for statistical analyses. The median concentrations of MAC, C5a, C3a and factor B were higher in active AAV patients (P < 0·001). Achievement of remission was associated with reductions in C3a (P = 0·005), C5a (P = 0·035) and factor B levels (P = 0·045), whereas MAC and properdin levels did not change. In active AAV, there were no effects of ANCA specificity, disease phenotype, previous immunosuppression or disease severity on complement levels. A total of 1122 articles were screened, and five studies, including this report, were entered into the meta-analysis. Plasma MAC, C5a and factor B in patients with active AAV were increased compared to patients in remission (excluding factor B) and controls. Changes in C3a were of borderline significance. Our findings and the results of the meta-analysis support activation of the complement system predominantly via the alternative pathway in AAV patients.

Short communication: Evaluation of an eating time sensor for use in pasture-based dairy systems

The assessment of grazing behavior is important for research and practice in pasture-grazed dairy farm systems. However, few devices are available that enable assessment of cow grazing behavior at an individual animal level. This study investigated whether commercially available Smarttag "eating time" sensors (Nedap Livestock Management, Groenlo, the Netherlands) were suitable for recording the grazing time of cows. Smarttag sensors were mounted on the neck collars of multiparous Holstein-Friesian cows in a herd in Taranaki, New Zealand. Cows were randomly selected each observation day from the milking herd for 8 separate days across a 1-mo period. Trained observers conducted 90-min observation periods to evaluate the relationship between the sensor eating time measure and grazing time. A set of 5 defined cow behaviors (2 "head up" and 3 "head down" behaviors) were assessed. In total, observations of 37 cows were recorded in 14 sessions over 8 d in the study period, providing 55.5 total hours of observations. Observation data were aligned with sensor data according to the sensor time stamps and grouped into matching 15-min intervals. Interobserver reliability was assessed both before and after the main trial period, and the mean percentage eating time per observer had a coefficient of variation of 0.46% [mean 93.2, standard deviation (SD) 0.425] before and 0.07% (mean 96.3, SD 0.074) after. In the main trial, the relationship between observed (mean 70.8%) and sensor-derived (mean 69.3%) percentage eating time over the observation period gave a Pearson correlation coefficient of 0.971, concordance correlation coefficient 0.968, mean difference 1.50% points, and SD 5.8% points. Therefore, sensor-identified percentage "eating time" and observed percentage active grazing time were shown to be both very well correlated and concordant (in agreement, with high correlation and little bias). Therefore, the relationship between observed and sensor-derived data had a high degree of agreement for identifying cow grazing activity. In conclusion, Smarttag sensors are a valid and useful tool for estimating grazing activity at time periods of 1 h or more.

Control of Reactive Oxygen Species for the Prevention of Parkinson's Disease: The Possible Application of Flavonoids

Oxidative stress reflects an imbalance between the production of reactive oxygen species (ROS) and antioxidant defense systems, and it can be associated with the pathogenesis and progression of neurodegenerative diseases such as multiple sclerosis, stroke, and Parkinson's disease (PD). The application of antioxidants, which can defend against oxidative stress, is able to detoxify the reactive intermediates and prevent neurodegeneration resulting from excessive ROS production. There are many reports showing that numerous flavonoids, a large group of natural phenolic compounds, can act as antioxidants and the application of flavonoids has beneficial effects in the adult brain. For instance, it is well known that the long-term consumption of the green tea-derived flavonoids catechin and epigallocatechin gallate (EGCG) can attenuate the onset of PD. Also, flavonoids such as ampelopsin and pinocembrin can inhibit mitochondrial dysfunction and neuronal death through the regulation of gene expression of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. Additionally, it is well established that many flavonoids exhibit anti-apoptosis and anti-inflammatory effects through cellular signaling pathways, such as those involving (ERK), glycogen synthase kinase-3β (GSK-3β), and (Akt), resulting in neuroprotection. In this review article, we have described the oxidative stress involved in PD and explained the therapeutic potential of flavonoids to protect the nigrostriatal DA system, which may be useful to prevent PD.

The primary system for measurement of beta emitting radioactive gases at KRISS

Korea Research Institute of Standards and Science (KRISS) is developing a length-compensated proportional counting (LCPC) system as a primary system for standardization of beta emitting radioactive gases. The pilot experiment was performed with ⁸⁵Kr and the optimized high voltage and pressure were found to be 1700 V and 0.203 MPa, respectively. The total activity of ⁸⁵Kr was deduced by the length compensation of each count. The expanded uncertainty was estimated to be around 0.8% (k = 2) for the ⁸⁵Kr measurement.

Efficient production of recombinant SARS-CoV-2 spike protein using the baculovirus-silkworm system

In the case of a new viral disease outbreak, an immediate development of virus detection kits and vaccines is required. For COVID-19, we established a rapid production procedure for SARS-CoV-2 spike protein (S protein) by using the baculovirus-silkworm expression system. The baculovirus vector-derived S proteins were successfully secreted to silkworm serum, whereas those formed insoluble structure in the larval fat body and the pupal cells. The ectodomain of S protein with the native sequence was cleaved by the host furin-protease, resulting in less recombinant protein production. The S protein modified in furin protease-target site was efficiently secreted to silkworm serum and was purified as oligomers, which showed immunoreactivity for anti-SARS-CoV-2 S2 antibody. By using the direct transfection of recombinant bacmid to silkworms, we achieved the efficient production of SARS-CoV-2 S protein as fetal bovine serum (FBS)-free system. The resultant purified S protein would be useful tools for the development of immunodetection kits, antigen for immunization for immunoglobulin production, and vaccines.

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Establishment of the BmNPV-silkworm expression system for production of the ectodomain of SARS-CoV-2 spike protein.

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The SARS-CoV-2 S protein with the native sequence was cleaved by the host silkworm furin protease.

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S protein without furin-cleavage site was purified as oligomeric structures.

Design of optimal digital filter and digital signal processing for a CdZnTe high resolution gamma-ray system

We have developed an online digital signal processing system based on an FPGA. The system consists of pile-up rejection, baseline restorer, peak detection and pole-zero cancellation for evaluation of deposited energy in the detector. The shaping algorithm employed is a Moving Window Deconvolution (MWD) to shape digitized data into a trapezoidal form. For the purpose of verification, the developed digital system was tested for ¹³⁷Cs gamma rays. The entire system is programmed using the LabVIEW environment.

Long-term mortality of patients with tuberculosis in Korea

BACKGROUND: Long-term mortality following tuberculosis (TB) diagnosis in Korea remains unclear.METHODS: The present study used data from the National Health Insurance Service database, an extensive health-related database including most Korean residents. TB patients were identified using International Classification of Diseases, Tenth Revision coding (A15-19, U88.0-88.1) and the type of anti-TB drug(s) between 2003 and 2016. Long-term mortality and causes of death in TB patients were analysed.RESULTS: A total of 357 211 individuals had TB over the period from 2003 to 2016 and 103 682 died. The mean age of the cohort was 54.7 ± 20.7 years, and 59.8% were male. The survival probability of TB patients at 1, 5, and 10 years after diagnosis was 87.8%, 75.3%, and 63.3%, respectively. High mortality and TB-related death rates were especially prominent in the early stages after TB diagnosis. The overall standardized mortality ratio of TB patients to the general Korean population was 3.23 (95% confidence interval 3.21-3.25).CONCLUSION: Mortality in TB patients was especially high in the early stages of disease after TB diagnosis, and mostly due to TB. This figure was approximately three-times higher than the mortality rate in the general population.

Human Activities Attract Harmful Mosquitoes in a Tropical Urban Landscape

Knowledge of the interrelationship of mosquito communities and land use changes is of paramount importance to understand the potential risk of mosquito disease transmission. This study examined the effects of land use types in urban, peri-urban and natural landscapes on mosquito community structure to test whether the urban landscape is implicated in increased prevalence of potentially harmful mosquitoes. Three land use types (park, farm, and forest nested in urban, peri-urban and natural landscapes, respectively) in Klang Valley, Malaysia, were surveyed for mosquito larval habitat, mosquito abundance and diversity. We found that the nature of human activities in land use types can increase artificial larval habitats, supporting container-breeding vector specialists such as Aedes albopictus, a dengue vector. In addition, we observed a pattern of lower mosquito richness but higher mosquito abundance, characterised by the high prevalence of Ae. albopictus in the urban landscape. This was also reflected in the mosquito community structure whereby urban and peri-urban landscapes were composed of mainly vector species compared to a more diverse mosquito composition in natural landscape. This study suggested that good environmental management practices in the tropical urban landscape are of key importance for effective mosquito-borne disease management.

Functional binding of E-selectin to its ligands is enhanced by structural features beyond its lectin domain

Selectins are key to mediating interactions involved in cellular adhesion and migration, underlying processes such as immune responses, metastasis, and transplantation. Selectins are composed of a lectin domain, an epidermal growth factor (EGF)-like domain, multiple short consensus repeats (SCRs), a transmembrane domain, and a cytoplasmic tail. It is well-established that the lectin and EGF domains are required to mediate interactions with ligands; however, the contributions of the other domains in mediating these interactions remain obscure. Using various E-selectin constructs produced in a newly developed silkworm-based expression system and several assays performed under both static and physiological flow conditions, including flow cytometry, glycan array analysis, surface plasmon resonance, and cell-rolling assays, we show here that a reduction in the number of SCR domains is correlated with a decline in functional E-selectin binding to hematopoietic cell E- and/or L-selectin ligand (HCELL) and P-selectin glycoprotein ligand-1 (PSGL-1). Moreover, the binding was significantly improved through E-selectin dimerization and by a substitution (A28H) that mimics an extended conformation of the lectin and EGF domains. Analyses of the association and dissociation rates indicated that the SCR domains, conformational extension, and dimerization collectively contribute to the association rate of E-selectin-ligand binding, whereas just the lectin and EGF domains contribute to the dissociation rate. These findings provide the first evidence of the critical role of the association rate in functional E-selectin-ligand interactions, and they highlight that the SCR domains have an important role that goes beyond the structural extension of the lectin and EGF domains.

P1368 Effect of angiotensin receptor blocker in patients with moderate or severe aortic stenosis: a randomized controlled trial

Funding Acknowledgements

This study was supported by grants from Boryung Pharmacy Research Fund.

Background/Introduction: Pathophysiology of aortic stenosis (AS) and several previous studies suggested the potential role of angiotensin receptor blocker (ARB) in patients with AS.

Purpose

We aimed to investigate the effects of Fimasartan, an ARB, on exercise capacity and progression of AS in patients with moderate to severe AS.

Methods

We conducted a prospective, randomized, double-blind, placebo-controlled trial in 32 normotensive or controlled-hypertensive patients with moderate or severe AS. Study participants were randomized to Fimasartan 30 mg to 60 mg daily (n = 14) or placebo (n = 18) for 1 year, and underwent cardiopulmonary exercise test, 6-minute walk test, and echocardiography at 0, 6, and 12 months, with follow-up data available in 29 subjects.

Results

Significant reductions in blood pressures were observed in the Fimasartan group but not in the placebo group. Two of the 14 patients in the Fimasartan group withdrew the study due to mild symptoms probably related with the decreased blood pressure, and one patient decline the study protocol. After the 12-month treatment, the peak oxygen consumption (VO2; the primary outcome) in the Fimasartan group was significantly decreased (from 28.3 ± 5.9 to 25.4 ± 3.8 mL/min/kg, P = 0.021) but not in the placebo group (P for interaction = 0.046) (Figure 1A). The severity of AS showed a gradual progression in both groups, without inter-group differences (mean transaortic pressure; Fimasartan group, +4.0 ± 3.8 mmHg/year; placebo group, +5.3 ± 6.2 mmHg/year; P for interaction = 0.429) (Figure 1B). Parameters of left ventricular systolic and diastolic function did not change in both groups.

Conclusions

The use of ARB impaired exercise capacity in patients with moderate or severe AS, and did not prevent the progression of AS. However, due to the small number of participants, further studies are required to confirm these findings.

Abstract P1368 Figure.

Purification and characterization of immunogenic recombinant virus-like particles of porcine circovirus type 2 expressed in silkworm pupae

Porcine circovirus type 2 (PCV2) is a primary causative agent of postweaningmultisystemic wasting syndrome (PMWS), which has a significant economic impact on the swine industry. The capsid protein (Cap) encoded by ORF2 of the viral genome has been used effectively as a vaccine against PCV2 infection. The Cap protein can spontaneously assemble into virus-like particles (VLPs) that are safe and highly immunogenic for vaccine applications. Several expression systems, including bacteria, yeast and insect cells, have been utilized to produce PCV2 VLPs. However, in some cases, the recombinant Cap (rCap) proteins produced in bacteria and yeast do not assemble spontaneously. In this study, we expressed rCap protein using a silkworm-baculovirus expression vector system (silkworm-BEVS) for mass production of PCV2 VLPs and established a simple three-step protocol for its purification from pupae: extraction by detergent, ammonium sulfate precipitation and anion exchange column chromatography. Size-exclusion chromatography (SEC) analysis and transmission electron microscope (TEM) observation showed that purified rCap proteins formed VLPs with a similar morphology to that of the original virus. Furthermore, the VLPs produced in silkworms were capable of inducing neutralizing antibodies against PCV2 in mice. Our results demonstrated that the silkworm system is a powerful tool for the production of PCV2 VLPs and will be useful for the development of a reliable and cost-effective PCV2 vaccine.

Identification of an insecticidal toxin produced by Enterobacter sp. strain 532 isolated from diseased Bombyx mori silkworms

Although Enterobacter sp. 532 shows pathogenicity in Bombyx mori, the insecticidal mechanisms are unclear. Here, we identified and characterised an insecticidal protein from Enterobacter. The insecticidal protein was purified from the strain and inoculated into B. mori larvae. Intracellular proteins were prepared, purified and separated by preparative native polyacrylamide gel electrophoresis (PAGE); one protein band had insecticidal activity. Sodium dodecyl sulfate-PAGE showed the presence of several bands, indicating that the insecticidal protein formed a complex. Peptide mass fingerprinting of a prominent 255.3-kDa band revealed 64 peptides that matched one protein with 33.0% sequence coverage. This protein was a homologue of the A component of the toxin complex (Tc), and the VRP1 domain was conserved; thus, the gene was named itcA (insecticidal toxin complex A). In the itcA downstream region, B and C component gene homologues were found, and these genes were located on an 86.2-kb contig sequence. Two repA genes and 27 genes related to conjugation transfer of plasmids were located on the contig, suggesting that the contig originated from a mobilisable plasmid. Therefore, these findings suggested that the strain may have acquired the Tc genes by horizontal transfer. This is the first description of Tc produced by the genus Enterobacter.

Surgical outcomes of tympanoplasty using a sterile acellular dermal allograft: a prospective randomised controlled study

Acellular human dermal allografts have been shown to be effective for soft-tissue implantation. We compared treatment outcomes of tympanoplasty using tragal perichondrium and acellular human dermal allograft (MegaDerm^®). In a prospective randomised controlled study, 60 patients scheduled to undergo tympanoplasty were randomly assigned to the autologous tragal perichondrium group (n = 33) or acellular human dermal allograft group (n = 27). Postoperative hearing gain, graft success rate at 1 and 6 months and operation times were compared between groups. Graft success rate, defined as the complete closure of tympanic membrane perforation, did not show any significant intergroup difference (75.8% vs 85.2%, p = 0.519). Air conduction thresholds and air-bone gaps showed significant improvements in both groups; from 38.7 ± 15.9 dB to 30.2 ± 15.6 dB (p < 0.001) and from 17.8 ± 7.3 dB to 11.5 ± 7.0 (p = 0.001) in the autologous tragal perichondrium group, and from 30.4 ± 12.2 dB to 24.5 ± 13.0 dB (p = 0.006) and from 14.3 ± 5.1 dB to 7.6 ± 4.6 dB (p < 0.001) in the acellular human dermal allograft group. The amount of hearing gain (p = 0.31) and closure of air-bone gap (p = 0.863) were not meaningfully different between groups. The mean operation time was significantly lower in the acellular human dermal allograft group (35.2 min vs 27.4 min, p = 0.039). In this prospective randomised controlled study, acellular human dermal allograft was shown to be an effective alternative to tragal perichondrium, with similar graft success rates and postoperative hearing results, but with reduced operation times.

Characterization of the RAGE-binding protein, Strongyloides venestatin, produced by the silkworm-baculovirus expression system

The receptor for advanced glycation end products (RAGE) recognizes Ca⁺⁺-binding proteins, such as members of the S100 protein family released by dead or devitalized tissues, and plays an important role in inflammatory responses. We recently identified the Ca⁺⁺-binding protein, venestatin, secreted from the rodent parasitic nematode, Strongyloides venezuelensis. We herein characterized recombinant venestatin, which is abundantly produced by the silkworm-baculovirus expression system (silkworm-BES), particularly in its interaction with RAGE. Venestatin from silkworm-BES possessed a binding capacity with Ca⁺⁺ ions and vaccine immunogenicity against S. venezuelensis larvae in mice, which is similar to venestatin produced by the E. coli expression system (EES). Venestatin from silkworm-BES had a higher affinity for human recombinant RAGE than that from EES, and their affinities were Ca⁺⁺-dependent. RAGE in the mouse lung co-immunoprecipitated with venestatin from silkworm-BES administered intranasally, indicating that it bound endogenous mouse RAGE. The present results suggest that venestatin from silkworm-BES affects RAGE-mediated pathological processes.

Functional horseradish peroxidase-streptavidin chimeric proteins prepared using a silkworm-baculovirus expression system for diagnostic purposes

Rapid, convenient, sensitive detection methods are of the utmost importance in analytical tools. Enzyme-based signal amplification using horseradish peroxidase (HRP) is commonly implemented in clinical diagnostics kits based on enzyme-linked immunosorbent assay (ELISA), by which the limit of detection is greatly improved. Herein we report the design and preparation of recombinant fusion proteins comprising HRP and streptavidin (Stav), in which HRP was fused to either the N- or C-terminus of Stav ((HRP)₄-Stav or Stav-(HRP)₄, respectively) using a baculovirus-silkworm expression system. Both (HRP)₄-Stav and Stav-(HRP)₄ were secreted in the apo form but they were easily converted to the holo form and activated by simple incubation with hemin overnight at 4 °C. The activated (HRP)₄-Stav and Stav-(HRP)₄ could be combined with a commercial biotinylated anti-OVA IgG antibody to detect ovalbumin (OVA) as the antigen in ELISA. The enzymatic activity of (HRP)₄-Stav was twofold higher than that of Stav-(HRP)₄, and the sensitivity of (HRP)₄-Stav in ELISA was higher than that of a commercial HRP-Stav chemical conjugate. The successful use of (HRP)₄-Stav chimeric protein as a molecular probe in ELISA shows that the baculovirus-silkworm expression system is promising to produce enzyme-Stav conjugates to substitute for those prepared by chemical methods.