Chronic kidney disease in postmenopausal women is associated with tooth loss.

OBJECTIVE: Menopause is characterized by changes in reproductive hormone levels that can negatively affect bone. Chronic kidney disease (CKD) and tooth loss are also important and common health issues after menopause. This study aimed to evaluate the association between CKD and tooth loss in postmenopausal women. METHODS: The study evaluated 64,971 participants who participated in the Korean National Health and Nutrition Examination Survey (KNHANES) from 2010-2018, including postmenopausal women, aged 40 to 79 years. Participants were divided into two groups based on the number of teeth in their dentition (≥20 and <20). MAIN OUTCOME MEASURES: The association between CKD and tooth loss was analyzed using multivariate logistic regression. Age, income, education, smoking, alcohol intake, body mass index, hypertension, diabetes, annual oral examination, toothbrushing, and the use of oral care products were considered. Subgroup analyses were further conducted according to age (40-65 yr and 66-79 yr). RESULTS: After adjusting for covariates, CKD and estimated glomerular filtration rate were significantly associated with having ≥20 teeth (PT20; CKD: odds ratio [OR] 1.41, 95% confidence interval [CI] 1.04-1.90; estimated glomerular filtration rate (10 mL/min/1.73 m2): OR 0.90, 95% CI 0.86-0.94). Importantly, the association between CKD and PT20 was significant in postmenopausal women, aged 66 to 79 years (OR 1.45, 95% CI 1.05-2.01). CONCLUSIONS: In postmenopausal women, CKD and tooth loss may be associated. The association is significant in postmenopausal women, aged 66 to 79 years.

Early functional factors for predicting outcome of independence in daily living after stroke: a decision tree analysis.

OBJECTIVE: This study aimed to investigate the predictive functional factors influencing the acquisition of basic activities of daily living performance abilities during the early stages of stroke rehabilitation using classification and regression analysis trees. METHODS: The clinical data of 289 stroke patients who underwent rehabilitation during hospitalization (164 males; mean age: 62.2 ± 13.9 years) were retrospectively collected and analysed. The follow-up period between admission and discharge was approximately 6 weeks. Medical records, including demographic characteristics and various functional assessments with item scores, were extracted. The modified Barthel Index on discharge served as the target outcome for analysis. A "good outcome" was defined as a modified Barthel Index score ≥ 75 on discharge, while a modified Barthel Index score < 75 was classified as a "poor outcome." RESULTS: Two classification and regression analysis tree models were developed. The first model, predicting activities of daily living outcomes based on early motor functions, achieved an accuracy of 92.4%. Among patients with a "good outcome", 70.9% exhibited (i) ≥ 4 points in the "sitting-to-standing" category in the motor assessment scale and (ii) 32 points on the Berg Balance Scale score. The second model, predicting activities of daily living outcome based on early cognitive functions, achieved an accuracy of 82.7%. Within the "poor outcome" group, 52.2% had (i) ≤ 21 points in the "visuomotor organization" category of Lowenstein Occupational Therapy Cognitive Assessment, (ii) ≤ 1 point in the "time orientation" category of the Mini Mental State Examination. CONCLUSION: The ability to perform "sitting-to-standing" and visuomotor organization functions at the beginning of rehabilitation emerged as the most significant predictors for achieving successful basic activities of daily living on discharge after stroke.

Development and evaluation of a multiplex real-time RT-PCR assay for simultaneous detection of H5, H7, and H9 subtype avian influenza viruses.

H5, H7 and H9 are the major subtypes of avian influenza virus (AIV) that cause economic losses in the poultry industry and sporadic zoonotic infection. Early detection of AIV is essential for preventing disease spread. Therefore, molecular diagnosis and subtyping of AIV via real-time RT-PCR (rRT-PCR) is preferred over other classical diagnostic methods, such as egg inoculation, RT-PCR and HI test, due to its high sensitivity, specificity and convenience. The singleplex rRT-PCRs for the Matrix, H5 and H7 gene used for the national surveillance program in Korea have been developed in 2017; however, these methods were not designed for multiplexing, and does not reflect the sequences of currently circulating strains completely. In this study, the multiplex H5/7/9 rRT-PCR assay was developed with sets of primers and probe updated or newly designed to simultaneously detect the H5, H7 and H9 genes. Multiplex H5/7/9 rRT-PCR showed 100% specificity without cross-reactivity with other subtypes of AIVs and avian disease-causing viruses or bacteria, and the limit of detection was 1-10 EID50/0.1 ml (50% egg infectious dose). Artificial mixed infections with the three different subtypes could be detected accurately with high analytical sensitivity even under highly biased relative molecular ratios by balancing the reactivities of each subtype by modifying the concentration of the primers and probes. The multiplex H5/7/9 rRT-PCR assay developed in this study could be a useful tool for large-scale surveillance programs for viral detection as well as subtyping due to its high specificity, sensitivity and robustness in discriminating viruses in mixed infections, and this approach would greatly decrease the time, cost, effort and chance of cross-contamination compared to the conventional method of testing three subtypes by different singleplex rRT-PCR methods in parallel or in series.

Optically Triggered Emergent Mesostructures in Monolayer WS2.

The ultrahigh surface area of two-dimensional materials can drive multimodal coupling between optical, electrical, and mechanical properties that leads to emergent dynamical responses not possible in three-dimensional systems. We observed that optical excitation of the WS2 monolayer above the exciton energy creates symmetrically patterned mechanical protrusions which can be controlled by laser intensity and wavelength. This observed photostrictive behavior is attributed to lattice expansion due to the formation of polarons, which are charge carriers dressed by lattice vibrations. Scanning Kelvin probe force microscopy measurements and density functional theory calculations reveal unconventional charge transport properties such as the spatially and optical intensity-dependent conversion in the WS2 monolayer from apparent n- to p-type and the subsequent formation of effective p-n junctions at the boundaries between regions with different defect densities. The strong opto-electrical-mechanical coupling in the WS2 monolayer reveals previously unexplored properties, which can lead to new applications in optically driven ultrathin microactuators.

High-Valence W6+ Ions Boost Cr2+ Activity in CrWO4 for Ideal Water Oxidation.

Electrocatalytic activity of multi-valence metal oxides for oxygen evolution reaction (OER) arises from various interactions among the constituent metal elements. Although the high-valence metal ions attract recent attentions due to the interactions with their neighboring 3d transition metal catalytic center, atomic-scale explanations for the catalytic efficiencies are still lacking. Here, by employing density functional theory predictions and experimental verifications, unprecedented electronic isolation of the catalytic 3d center (M2+) induced by the surrounding high-valence ions such as W6+ is discovered in multivalent oxides MWO4 (M = Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn). Due to W6+'s extremely high oxidation state with the minimum electron occupations (d0), the surrounding W6+ blocks electron transfer toward the catalytic M2+ ions and completely isolates the ions electronically. Now, the isolated M2+ ions solely perform OER without any assistant electron flow from the adjacent metal ions, and thus the original strong binding energies of Cr with OER intermediates are effectively moderated. Through exploiting "electron isolators" such as W6+ surrounding the catalytic ion, exploring can be done beyond the conventional materials such as Ni- or Co-oxides into new candidate groups such as Cr and Mn on the left side of the periodic table for ideal OER.

Multichannel Hierarchical Analysis of Time-Resolved Hyperspectral Data for Advanced Colorimetric E-Nose.

The colorimetric sensor-based electronic nose has been demonstrated to discriminate specific gaseous molecules for various applications, including health or environmental monitoring. However, conventional colorimetric sensor systems rely on RGB sensors, which cannot capture the complete spectral response of the system. This limitation can degrade the performance of machine learning analysis, leading to inaccurate identification of chemicals with similar functional groups. Here, we propose a novel time-resolved hyperspectral (TRH) data set from colorimetric array sensors consisting of 1D spatial, 1D spectral, and 1D temporal axes, which enables hierarchical analysis of multichannel 2D spectrograms via a convolution neural network (CNN). We assessed the outstanding classification performance of the TRH data set compared to an RGB data set by conducting a relative humidity (RH) concentration classification. The time-dependent spectral response of the colorimetric sensor was measured and trained as a CNN model using TRH and RGB sensor systems at different RH levels. While the TRH model shows a high classification accuracy of 97.5% for the RH concentration, the RGB model yields 72.5% under identical conditions. Furthermore, we demonstrated the detection of various functional volatile gases with the TRH system by using experimental and simulation approaches. The results reveal distinct spectral features from the TRH system, corresponding to changes in the concentration of each substance.

Clonal Distribution and Its Association With the Carbapenem Resistance Mechanisms of Carbapenem-Non-Susceptible Pseudomonas aeruginosa Isolates From Korean Hospitals.

Background: Carbapenem resistance in Pseudomonas aeruginosa is a serious global health problem. We investigated the clonal distribution and its association with the carbapenem resistance mechanisms of carbapenem-non-susceptible P. aeruginosa isolates from three Korean hospitals. Methods: A total of 155 carbapenem-non-susceptible P. aeruginosa isolates collected between 2011 and 2019 were analyzed for sequence types (STs), antimicrobial susceptibility, and carbapenem resistance mechanisms, including carbapenemase production, the presence of resistance genes, OprD mutations, and the hyperproduction of AmpC ß-lactamase. Results: Sixty STs were identified in carbapenem-non-susceptible P. aeruginosa isolates. Two high-risk clones, ST235 (N=41) and ST111 (N=20), were predominant; however, sporadic STs were more prevalent than high-risk clones. The resistance rate to amikacin was the lowest (49.7%), whereas that to piperacillin was the highest (92.3%). Of the 155 carbapenem-non-susceptible isolates, 43 (27.7%) produced carbapenemases. Three metallo-ß-lactamase (MBL) genes, blaIMP-6 (N=38), blaVIM-2 (N=3), and blaNDM-1 (N=2), were detected. blaIMP-6 was detected in clonal complex 235 isolates. Two ST773 isolates carried blaNDM-1 and rmtB. Frameshift mutations in oprD were identified in all isolates tested, regardless of the presence of MBL genes. Hyperproduction of AmpC was detected in MBL gene-negative isolates. Conclusions: Frameshift mutations in oprD combined with MBL production or hyperproduction of AmpC are responsible for carbapenem resistance in P. aeruginosa. Further attention is required to curb the emergence and spread of new carbapenem-resistant P. aeruginosa clones.

The first record of leucism in the Rhabdophis tigrinus (Boie, 1826) (Squamata, Colubridae) in South Korea.

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

Electrochemical Evolution of Ru-Based Polyoxometalates into Si,W-Codoped RuOx for Acidic Overall Water Splitting.

Despite intensive studies over decades, the development of electrocatalysts for acidic water splitting still relies on platinum group metals, especially Pt and Ir, which are scarce, expensive, and poorly sustainable. Because such problems can be alleviated, Ru-based bifunctional catalysts such as rutile RuO2 have recently emerged. However, RuO2 has a relatively low activity for hydrogen evolution reactions (HER) and low stability for oxygen evolution reactions (OER) under acidic conditions. In this study, the synthesis of a RuOx -based bifunctional catalyst (RuSiW) for acidic water splitting via the electrochemical evolution from Ru-based polyoxometalates at cathodic potentials is reported. RuSiW consists of the nanocrystalline RuO2 core and Si,W-codoped RuOx shell. RuSiW exhibits outstanding HER and OER activity comparable to Pt/C and RuO2 , respectively, with high stability. Computational analysis suggests that the codoping of RuOx with W and Si synergistically improves the HER activity of otherwise poor RuO2 by shifting the d-band center and optimizing atomic configurations beneficial for proper hydrogen adsorption. This study provides insights into the design and synthesis of unprecedented bifunctional electrocatalysts using catalytically inactive and less explored elements, such as Si and W.

Analogous Design of a Microlayered Silicon Oxide-Based Electrode to the General Electrode Structure for Thin-Film Lithium-Ion Batteries.

Development of miniaturized thin-film lithium-ion batteries (TF-LIBs) using vacuum deposition techniques is crucial for low-scale applications, but addressing low energy density remains a challenge. In this work, structures analogous to SiOx-based thin-film electrodes are designed with close resemblance to traditional LIB slurry formulations including active material, conductive agent, and binder. The thin-film is produced using mid-frequency sputtering with a single hybrid target consisting of SiOx nanoparticles, carbon nanotubes, and polytetrafluoroethylene. The thin-film SiOx/PPFC (plasma-polymerized fluorocarbon) involves a combination of SiOx and conductive carbon within the PPFC matrix. This results in enhanced electronic conductivity and superior elasticity and hardness in comparison to a conventional pure SiOx-based thin-film. The electrochemical performance of the half-cell consisting of thin-film SiOx/PPFC demonstrates remarkable cycling stability, with a capacity retention of 74.8% up to the 1000th cycle at 0.5 C. In addition, a full cell using the LiNi0.6Co0.2Mn0.2O2 thin-film as the cathode material exhibits an exceptional initial capacity of ≈120 mAh g-1 at 0.1 C and cycle performance, marked by a capacity retention of 90.8% from the first cycle to the 500th cycle at a 1 C rate. This work will be a stepping stone for the AM/CB/B composite electrodes in TF-LIBs.

Molecularly Selective Polymer Interfaces for Electrochemical Separations.

The molecular design of polymer interfaces has been key for advancing electrochemical separation processes. Precise control of molecular interactions at electrochemical interfaces has enabled the removal or recovery of charged species with enhanced selectivity, capacity, and stability. In this Perspective, we provide an overview of recent developments in polymer interfaces applied to liquid-phase electrochemical separations, with a focus on their role as electrosorbents as well as membranes in electrodialysis systems. In particular, we delve into both the single-site and macromolecular design of redox polymers and their use in heterogeneous electrochemical separation platforms. We highlight the significance of incorporating both redox-active and non-redox-active moieties to tune binding toward ever more challenging separations, including structurally similar species and even isomers. Furthermore, we discuss recent advances in the development of selective ion-exchange membranes for electrodialysis and the critical need to control the physicochemical properties of the polymer. Finally, we share perspectives on the challenges and opportunities in electrochemical separations, ranging from the need for a comprehensive understanding of binding mechanisms to the continued innovation of electrochemical architectures for polymer electrodes.

PmrAB controls virulence-associated traits and outer membrane vesicle biogenesis in Acinetobacter baumannii.

The PmrAB two-component system modulates colistin resistance in Acinetobacter baumannii, but its association with the virulence traits of this bacterium remains uncharacterized. This study explored the role of A. baumannii PmrAB in surface motility, biofilm formation, and outer membrane vesicle (OMV) biogenesis using wild-type (WT) A. baumannii 17978 and ΔpmrA and ΔpmrB mutant strains. The two mutant strains exhibited significantly decreased surface motility compared with that of WT strain by the low expression of abaI, abaR, A1S_0113, A1S_0115, and A1S_0116. Biofilm mass also significantly decreased in the two mutant strains at 12 h of incubation, but restored at 24 h. Under static culture conditions for 12 h, the two mutant strains showed low pgaA expression. However, the other biofilm-associated genes, such as csuC, csuE, ompA, and bap, showed different expression between the two mutant strains. Although the size of OMVs was similar among the three strains, the number of OMVs secreted from the two mutant strains slightly decreased compared with that secreted from the WT strain. Protein concentrations in the OMVs of ΔpmrA mutant significantly decreased compared with those in the OMVs of WT and ΔpmrB strains. Overall, PmrAB modulates virulence traits and OMV biogenesis in A. baumannii.

Photocatalytic H2O2 production from water and air using porous organic polymers.

Producing hydrogen peroxide (H2O2) from H2O and O2 under visible light irradiation is a promising solar-to-chemical energy conversion technology. Hydrogen peroxide has versatile applications as a green oxidant and liquid energy carrier but has been produced through energy-intensive and complex anthraquinone processes. Herein, we report the rational design of efficient and stable porous organic polymer (POP) containing redox centers, anthraquinone photocatalyst (ANQ-POP) for solar H2O2 production. ANQ-POP is readily synthesized with stable dioxin-linkages via efficient one-pot, transition-metal-free nucleophilic aromatic substitution reactions between 1,2,3,4,5,6,7,8-octafluoro-9,10-anthraquinone (OFANQ) and 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP). Exhibiting a fibrillar morphology, ANQ-POP boasts a high surface area of 380 m2∙g-1 and demonstrates thermal stability. With 10 % ethanol, ANQ-POP yields an H2O2 production rate of 320 µmol g-1 under visible light irradiation. Moreover, ANQ-POP alone can efficiently produce H2O2 without any photosensitizers and cocatalysts. Density functional theory calculations reveal that the quinone groups of the anthraquinone moieties can serve as redox centers for H2O2 production under light irradiation. Furthermore, unlike most conventional photocatalysts, it can produce H2O2 using only water and air by catalyzing both oxygen reduction and evolution reactions under light irradiation. Our findings provide an efficient, eco-friendly pathway for photocatalytic production of H2O2 under mild reaction conditions using a dioxin-derived POP-based photocatalyst.

The Impact of (COVID)-19 on Beverage Purchasing Behaviors in Korea.

Objective: In this study, we examined changes in purchase behavior of alcoholic beverages (ie, soju, beer, wine, traditional Korean liquor, and liquor) and non-alcoholic beverages (ie, fruit and vegetable juices, coffee, tea, bottled water, milk, yogurt, and plant-based milk) before and after the COVID-19 pandemic. Methods: Monthly beverage expenditure data, based on Korean household demographic information, was used for 3 years and 6 months. The 2-part model was used for analysis. To examine the effect of COVID-19, beverage expenditure was analyzed after dividing it into short-term and long-term effects. Results: Our results show that the probability of purchasing alcoholic beverages increased owing to the long-term effect of the COVID-19 pandemic. The amounts of beer, wine, and traditional Korean liquor purchased increased in the long-term. The purchase of sweet drinks decreased (ie, fruit and vegetable juices and yogurt) in the long-term because of the effect of the pandemic. On the other hand, tea, water, and plant-based milk expenditures increased. Conclusion: This beverage consumption pattern reflects both unhealthy (ie, an increase in alcoholic beverage purchases) and healthy drinking behaviors (ie, a decrease in sweet beverage purchases and an increase in tea, water, and plant-based milk purchases).

Association between birth-related factors and periodontitis in women: Korea National Health and Nutrition Examination Survey 2013-2018.

AIM: Adult women experience several changes in physiological status, such as pregnancy and childbirth, during their life cycle. This study analyses the association between birth-related factors (the number of childbirths, abortions and miscarriages) and periodontitis using data from the Korea National Health and Nutrition Examination Survey, which represents Korean adults. MATERIALS AND METHODS: The study used data from Korea National Health and Nutrition Examination Survey VI and VII (2013-2018) and included 10,072 women 19 years or older, with no missing data on the variables assessed. Periodontitis was defined according to the Community Periodontal Index (CPI) criteria. Multiple logistic regression analysis, adjusting for age, household income, education, alcohol consumption, smoking, stress, body mass index, waist circumference, hypertension, diabetes mellitus, an oral examination within 1 year, daily tooth brushing frequency, hygiene products and self-perceived oral health as identified via logistic regression analyses, was performed to determine the association between birth-related variables and periodontitis. RESULTS: In the crude model, the odds ratio (OR) showed a significantly increased risk of periodontitis (CPI ≥ 3) and severe periodontitis (CPI = 4) based on the number of childbirths, abortions and miscarriages (p < .05). After covariate adjustment, periodontitis (CPI ≥ 3) was associated with the number of childbirths (1: OR = 1.92; 95% confidence interval [CI]: 1.47-2.50; 2: OR = 2.03; 95% CI: 1.57-2.61; ≥3: OR = 2.11; 95% CI: 1.60-2.78). Furthermore, severe periodontitis (CPI = 4) was also associated with the number of childbirths (1: OR = 2.33; 95% CI: 1.24-4.38; 2: OR = 2.99; 95% CI: 1.62-5.52; ≥3: OR = 3.34; 95% CI: 1.79-6.21). CONCLUSIONS: The findings of this large-scale, nationally representative study suggest that the number of childbirths is associated with the severity of periodontitis. However, the relationship between the number of abortions and miscarriages and periodontitis (CPI ≥ 3) or severe periodontitis (CPI = 4) is not significant.

Antibacterial and biofilm-inhibiting cotton fabrics decorated with copper nanoparticles grown on graphene nanosheets.

Infectious pathogens can be transmitted through textiles. Therefore, additional efforts are needed to develop functional fabrics containing antimicrobial substances to prevent the growth of antibiotic-resistant bacteria and their biofilms. Here, we developed a cotton fabric coated with reduced graphene oxide (rGO) and copper nanoparticles (Cu NPs), which possessed hydrophobic, antimicrobial, and anti-biofilm properties. Once the graphene oxide was dip-coated on a cellulose cotton fabric, Cu NPs were synthesized using a chemical reduction method to fabricate an rGO/Cu fabric, which was analyzed through FE-SEM, EDS, and ICP-MS. The results of our colony-forming unit assays indicated that the rGO/Cu fabric possessed high antibacterial and anti-biofilm properties against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis, Corynebacterium xerosis, and Micrococcus luteus. Particularly, the fabric could inhibit the growth of E. coli, C. xerosis, and M. luteus with a 99% efficiency. Furthermore, our findings confirmed that the same concentrations of rGO/Cu had no cytotoxic effects against CCD-986Sk and Human Dermal Fibroblast (HDF), human skin cells, and NIH/3T3, a mouse skin cell. The developed rGO/Cu fabric thus exhibited promising applicability as a cotton material that can maintain hygienic conditions by preventing the propagation of various bacteria and sufficiently suppressing biofilm formation while also being harmless to the human body.

Subtype specific virus enrichment with immunomagnetic separation method followed by NGS unravels the mixture of H5 and H9 avian influenza virus.

Wild bird avian influenza type A virus (AIV) surveillance is important for the early detection of highly pathogenic AIVs and for providing early warnings to the poultry industry and veterinary services to implement more effective control measures against these viruses. Some field samples are often found to contain more than two kinds of AIV. Correct determination of the HA/NA subtype and complete nucleotide sequences of the component viruses in those samples are often critical for timely and accurate understanding of the field situation, but it is not easy to define the genomic structure of the constituent viruses unambiguously because AIV has eight segmented genomes. In this study, with immunomagnetic beads incorporating polyclonal antibodies of chicken for subtype-specific viral enrichment, we could selectively decrease the density of one of the two constituent viruses in a sample of different subtypes, H5 and H9, artificially generated; this was represented in the changes of Ct values with subtype specific real-time RT-PCR. Following this, with NGS, we could recover nearly complete genomic sequences and arrange the consensus sequences of gene segments of the constituent viruses confidently with the quantitative variable like genome coverage, linked along the gene segments and associated with the number of viral copies in a sample.

Antimicrobial activity of α-mangostin against Staphylococcus species from companion animals in vitro and therapeutic potential of α-mangostin in skin diseases caused by S. pseudintermedius.

Antimicrobial resistance in Staphylococcus species from companion animals is becoming increasingly prevalent worldwide. S. pseudintermedius is a leading cause of skin infections in companion animals. α-mangostin (α-MG) exhibits various pharmacological activities, including antimicrobial activity against G (+) bacteria. This study investigated the antimicrobial activity of α-MG against clinical isolates of Staphylococcus species from companion animals and assessed the therapeutic potential of α-MG in skin diseases induced by S. pseudintermedius in a murine model. Furthermore, the action mechanisms of α-MG against S. pseudintermedius were investigated. α-MG exhibited antimicrobial activity against clinical isolates of five different Staphylococcus species from skin diseases of companion animals in vitro, but not G (-) bacteria. α-MG specifically interacted with the major histocompatibility complex II analogous protein (MAP) domain-containing protein located in the cytoplasmic membrane of S. pseudintermedius via hydroxyl groups at C-3 and C-6. Pretreatment of S. pseudintermedius with anti-MAP domain-containing protein polyclonal serum significantly reduced the antimicrobial activity of α-MG. The sub-minimum inhibitory concentration of α-MG differentially regulated 194 genes, especially metabolic pathway and virulence determinants, in S. pseudintermedius. α-MG in pluronic lecithin organogel significantly reduced the bacterial number, partially restored the epidermal barrier, and suppressed the expression of cytokine genes associated with pro-inflammatory, Th1, Th2, and Th17 in skin lesions induced by S. pseudintermedius in a murine model. Thus, α-MG is a potential therapeutic candidate for treating skin diseases caused by Staphylococcus species in companion animals.

Acinetobacter baumannii under Acidic Conditions Induces Colistin Resistance through PmrAB Activation and Lipid A Modification.

Colistin is a last-resort antimicrobial agent for treating carbapenem-resistant Acinetobacter baumannii infections. The activation of PmrAB by several environmental signals induces colistin resistance in Gram-negative bacteria. This study investigated the molecular mechanisms of colistin resistance in A. baumannii under acidic conditions using wild-type (WT) A. baumannii 17978, ΔpmrA and ΔpmrB mutants, and pmrA-complemented strains. The pmrA or pmrB deletion did not affect the growth of A. baumannii under acidic or aerobic conditions. A. baumannii under acidic (pH 5.5) and high-iron (1 mM) conditions showed 32- and 8-fold increases in the minimum inhibitory concentrations (MICs) of colistin, respectively. The ΔpmrA and ΔpmrB mutants at pH 5.5 showed a significant decrease in colistin MICs compared to the WT strain at pH 5.5. No difference in colistin MICs was observed between WT and mutant strains under high-iron conditions. The pmrCAB expression significantly increased in the WT strain at pH 5.5 compared to the WT strain at pH 7.0. The pmrC expression significantly decreased in two mutant strains at pH 5.5 compared to the WT strain at pH 5.5. The PmrA protein was expressed in the ΔpmrA strain carrying ppmrA_FLAG plasmids at pH 5.5 but not at pH 7.0. Lipid A modification by the addition of phosphoethanolamine was observed in the WT strain at pH 5.5. In conclusion, this study demonstrated that A. baumannii under acidic conditions induces colistin resistance via the activation of pmrCAB operon and subsequent lipid A modification.

Statistical Analysis of the Performance of Local Veterinary Laboratories in Molecular Detection (rRT-PCR) of Avian Influenza Virus via National Proficiency Testing Performed during 2020-2022.

For the early detection of avian influenza virus (AIV), molecular diagnostic methods such as real-time RT-PCR (rRT-PCR) are the first choice in terms of accuracy and speed in many countries. A laboratory's capability to perform this diagnostic method needs to be measured through external and independent assessment to ensure that the method is validated within the laboratory and in interlaboratory comparison. The Animal and Plant Quarantine Agency of Korea has implemented five rounds of proficiency testing (PT) for rRT-PCR targeting local veterinary service laboratories involved in the AIV national surveillance program from 2020 to 2022. In each round, a portion composed of six or more samples was selected from the entire PT panel consisting of H5, H7, and H9 viruses isolated in Korea and distributed to each participant, and at least one pair of samples was commonly included in each panel for interlaboratory comparison. During the five rounds of PT, a few incorrect and outlying results were detected that required immediate inspection or corrective actions. However, in the quantitative measurement of Ct values, the average standard deviation or coefficient of variation decreased as multiple PT rounds progressed, and a positive correlation between consecutive rounds of PT was observed since 2021. The better consistency or stability in the experimental performance appeared to contribute to the more harmonized results in the latest PTs, and it is assumed that the positive reaction of participants to the challenges of quantitative assessment reports showing their status intuitively might work. We need to continue operating the PT program for local laboratories because they play crucial roles at the front line of the national avian influenza surveillance program, and frequent changes in the human resources or environment for diagnosis in those laboratories are inevitable.