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The positive effects of Actinidia eriantha cv. Bidan extract (AEE) were investigated in terms of improvement in Aβ1-42-induced cognitive impairment. AEE was shown to have neuroprotective effects, such as reduction in intracellular reactive oxygen species levels and suppression of apoptotic cell death, in neuron-like PC-12 cells. Results of the in vivo experiment showed that AEE at 200 and 1,000 mg/kg body weight/day, and even at 50 mg/kg body weight/day, reduced impairments in learning and spatial memory in Aβ1-42-treated ICR mice. Furthermore, the endogenous antioxidant systems (SOD, CAT, and GSH/GSSG) in the mouse brain tissue significantly (p < 0.05) increased by AEE administration compared with the group treated with only Aβ1-42. In the analysis of UPLC-Q-TOF mass spectrometry, caffeic acid derivatives such as caffeoylquinic acids were identified in AEE. These results suggest that the Bidan kiwifruit is a good source of antioxidant phenolics that hold the potential to improve cognitive function.

ABSTRACT Streptococcus parauberis is the dominant etiological agent of streptococcosis, the most devastating bacterial disease in the olive flounder farming industry in South Korea. In this study, the distribution of serotypes, antimicrobial susceptibility, and presence of antimicrobial resistance genes (ARGs) in S. parauberis isolates obtained between 1999 and 2021 was thoroughly investigated to gain insight into the dynamics of their presence and the relationship between serotypes and antimicrobial resistance. Disk diffusion testing of 103 isolates against 10 antimicrobial agents was performed, and epidemiological cut-off values generated through normalized resistance interpretation analysis were used to classify wild-type (WT) and non-wild-type (NWT) populations. Principal component analysis and hierarchical clustering were implemented to achieve an understanding on the relationship between serotypes and antimicrobial resistance patterns. PCR-based serotyping showed that serotype Ia (67.1%) was the most prevalent in South Korea, followed by serotypes Ib/Ic (25.2%) and II (7.7%). The highest proportion of isolates was assigned to NWT against amoxicillin (80.6%), followed by oxytetracycline (77.7%) and erythromycin (48.5%). The time-scale data showed that recently obtained serotypes Ib/Ic and II isolates tended to be categorized as NWT populations resistant to more antibiotics, possibly due to microbial adaptation to antibiotic pressure. ARGs responsible for resistance to oxytetracycline and erythromycin were found only in NWT populations in serotype Ia [tet(S) and erm(B), respectively], and serotype II [tet(M) and mef(J)-msr(I), respectively]. We also found that the mef-msr gene pair in S. parauberis serotype II might be involved in low-level resistance to erythromycin. IMPORTANCE This study presents serotype distribution and antimicrobial susceptibility data along with the antimicrobial resistance genes (ARGs) of Streptococcus parauberis, which is an important bacterial fish pathogen worldwide. In particular, almost all oxytetracycline and erythromycin non-wild-type (NWT) populations harbored tet(S) or tet(M), and erm(B) or mef(J)-msr(I), respectively. Interestingly, these ARGs were distributed in a highly serotype-dependent manner, resulting in a clear correlation between the antibiogram and serotype distribution. Moreover, recent isolates belonging to serotypes Ib/Ic and II tended to be more frequently categorized as NWT against antimicrobials, including amoxicillin and cefalexin compared to old isolates, while a dramatic decrease in erythromycin and clindamycin NWT frequencies was observed in recent serotype Ia isolates, which lacked erm(B). These variations might be attributed to shifts in the antibiotics employed in South Korean aquaculture over time. The overall findings would provide important background knowledge for understanding the epidemiology of S. parauberis infection in aquaculture.

Rock bream iridovirus (RBIV) causes severe mass mortalities in rock bream (Oplegnathus fasciatus) and remains an unsolved problem in Korea aquaculture industry. In this study, we assessed the potential of ankyrin repeat (ANK)-containing proteins to induce protective immunity in RBIV-infected rock bream. Rock bream administered with ankyrin repeat-containing protein-based DNA vaccine (200 ng/fish) exhibited significant protection against at 4 and 8 weeks post vaccination to infected with 6.7 × 105 RBIV at 23°C; relative percent survival (RPS) of 60.04% and 40.1%, respectively. Furthermore, survivors from the first infection were strongly protected from RBIV (1.1 × 107) re-infection at 70 days post infection, as 100% RPS was observed and without clinical signs of RBIV diseases. Moreover, TLR3 (9.5-fold), TLR9 (5.2-fold), MyD88 (15.9-fold), Mx (55.5-fold), ISG15 (19.0-fold), PKR (24.2-fold), MHC class I (5.1-fold), perforin (6.5-fold), Fas (6.4-fold), Fas ligand (7.1-fold), caspase8 (5.0-fold), caspase9 (12.5-fold), and caspase3 (6.3-fold) responses were significantly elevated in the muscle (vaccine injection site) of ANK-based DNA vaccinated fish at 7 days post vaccination. However, inflammatory cytokines (IL1β, IL8, and TNFα) were not enhanced in the vaccinated rock bream. Moreover, ANK gene may be a good candidate to detect RBIV infection or in revealing specific information to elucidate the pathogenic mechanisms underlying RBIV infection. In summary, ANK-based DNA vaccination in rock bream induced TLR- and IFN-mediated or apoptosis-related immune responses and suggest efficient preventive measures against RBIV.

Marine algae possess a variety of beneficial effects on human health. In this study, we investigated whether diphlorethohydroxycarmalol (DPHC), isolated from Ishige okamurae, a brown alga, suppresses receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation. DPHC significantly suppressed RANKL-induced osteoclast differentiation and macrophage-colony stimulating factor (M-CSF) expression in a dose-dependent manner. In addition, it significantly inhibited actin ring formation, the expression of osteoclast marker genes, such as tartrate-resistant acid phosphatase (TRAP), nuclear factor of activated T-cells cytoplasmic 1 (Nfatc1), cathepsin K (Ctsk), and dendritic cell-specific transmembrane protein (Dcstamp), and osteoclast-induced bone resorption. Analysis of the RANKL-mediated signaling pathway showed that the phosphorylation of both IκB and p65 was specifically inhibited by DPHC. These results suggest that DPHC substantially suppresses osteoclastogenesis by downregulating the RANK-NF-κB signaling pathway. Thus, it holds significant potential for the treatment of skeletal diseases associated with an enhanced osteoclast activity. [ABSTRACT FROM AUTHOR]

An analytical method for the quantification of acrylic acid (AA), 1,3-propanediol (1,3-PD) and 3-hydroxypropionic acid (3-HP) in the bio-catalytic conversion process has been developed by gas chromatography. A simple liquid-liquid extraction (LLE) procedure was used in the sample preparation. Organic acid additives such as trifluoroacetic acid were used to improve the extraction efficiency in the LLE procedure. Under optimum analysis conditions, all analytes were satisfactorily separated with no interference. In standard calibration, all correlation coefficients (r(2)) were better than or equal to 0.994. In culture media, the intra-batch precision (% relative standard deviation) and recovery (%) as the average value of the quality control samples were 2.3 and 102.4%, respectively. In addition, the inter-batch precision and recovery as the average value of the quality control samples were 5.0 and 104.0%, respectively. In phosphate buffer, the intra-batch precision and recovery as the average value of the quality control samples were 2.7 and 101.6%, respectively. In addition, the inter-batch precision and recovery as the average value of the quality control samples were 2.9 and 101.7%, respectively. The limit of detection (S/N ratio: 3) and limit of quantification (S/N ratio: 10) were 1.0 and 3.5 µg/mL, 3.0 and 10.0 µg/mL, and 9.0 and 30.0 µg/mL, respectively, for AA, 1,3-PD and 3-HP. Consequently, this method was demonstrated to be acceptable for the quantitative analysis of AA, 1,3-PD and 3-HP in culture media and phosphate buffer. [ABSTRACT FROM AUTHOR]

Extracting single-cell information during cellular responses to external signals in a high-throughput manner is an essential step for quantitative single-cell analyses. Here, we have developed a simple yet robust microfluidic platform for measuring time-course single-cell response on a large scale. Our method combines a simple microwell-based cell docking process inside a patterned microfluidic channel, with programmable time-course live-cell imaging and software-aided fluorescent image processing. The budding yeast, Saccharomyces cerevisiae(S. cerevisiae), cells were individually captured in microwells by multiple sweeping processes, in which a cell-containing solution plug was actively migrating back and forth several times by a finger-pressure induced receding meniscus. To optimize cell docking efficiency while minimizing unnecessary flooding in subsequent steps, circular microwells of various channel dimensions (4–24 µm diameter, 8 µm depth) along with different densities of cell solution (1.5–6.0 × 109cells per mL) were tested. It was found that the microwells of 8 µm diameter and 8 µm depth allowed for an optimal docking efficiency (>90%) without notable flooding issues. For quantitative single-cell analysis, time-course (time interval 15 minute, for 2 hours) fluorescent images of the cells stimulated by mating pheromone were captured using computerized fluorescence microscope and the captured images were processed using a commercially available image processing software. Here, real-time cellular responses of the mating MAPK pathway were monitored at various concentrations (1 nM–100 µM) of mating pheromone at single-cell resolution, revealing that individual cells in the population showed non-uniform signaling response kinetics. [ABSTRACT FROM AUTHOR]

Defoliation (DF) on peach (Prunus persica L.) and Japanese apricot (Prunus mume Sieb. et Zucc.) trees caused by a hailstorm in 2017, year 1, was investigated for its effects on growth and fruit yield in South Korea over four years, comparing with recovery effects of the DF trees treated with repeated immediate pruning (IP) right after the storm. Treatments included 0–10, 10–40, 40–70, and 70–100% of DF trees, with 0–10, 10–40, 40–70, and 70–100% of DF + IP trees. The hailstorms increased the damages to shoots for peaches and to shoots and scaffold for Japanese apricot trees in year 1, with fruit yield reduced more than 80% observed on 10–100 DF of both fruit species. The IP treatment increased the number of new shoots in years 2–4 but reduced shoot length and diameter of peach and Japanese apricot trees. Tree canopy in years 2–4 was reduced on 40–100 DF of peach trees and on 70–100 of DF and DF + IP of Japanese apricot trees. The 40–100 DF Japanese apricot trees resulted in a fruit yield index of less than 90% for years 2–4, which was observed on 40–100 DF+IP trees only in year 2 due to balanced tree vegetative and reproductive growth.

Adjuvant activity of saponins extracted from the South American tree QuiLLaja saponaria has been demonstrated with many antigens. Recently, four saponin fractions (designated as QS-7, QS-17, QS-18, and QS-21) with adjuvant activity were purified by reverse phase chromatography. In particular, efficacy of the less toxic QS-21 fraction has been demonstrated with several recombinant viral antigens including HIV gp120. Here, we report a novel saponin fraction (designated as QS-Ll) derived from Quillaja saponaria. Unlike previously identified saponins, QS-Ll had a different chemical structure and showed adjuvant activity only when administered in the presence of alum-precipitated antigen. Interestingly, the QS-Ll greatly increased not only a humoral immune response but also cellular immune response to recombinant hepatitis B virus surface antigen (HBsAg). Furthermore, QS-Ll showed lower toxicity in vivo and in vitro than the previously identified saponin fraction, QS-21. Finally, we examined the chemical structure of the QS-Ll using mass spectroscopic analysis, carbohydrate composition analysis and NMR spectroscopic analysis. Thus, our results indicated that this novel QS-Ll saponin fraction had several desirable properties required for an effective adjuvant. [ABSTRACT FROM AUTHOR]