Sublethal Sodium Hypochlorite Exposure: Impact on Resistance-Nodulation-Cell Division Efflux Pump Overexpression and Cross-Resistance to Imipenem.

Sodium hypochlorite (NaOCl) is widely used in public healthcare facilities; this exposure can result in the development of bacterial tolerance to disinfectants, which has known links to antibiotic cross-resistance. However, the mechanism through which cross-resistance to antibiotics and disinfectants develops remains ambiguous. Therefore, this study aimed to examine the phenotypic and transcriptomic changes caused by disinfectant exposure in Gram-negative bacteria and determine the cause of cross-resistance to antibiotics. The results demonstrated that the misuse of disinfectants plays an important role in the emergence of disinfectant resistance and in the increase in antibiotic resistance. Antibiotic resistance may occur from the exposure of Gram-negative bacteria to subminimal inhibitory concentrations (MICs) of NaOCl. Ten passages of Gram-negative bacteria in increasingly higher subMICs of the NaOCl disinfectant were sufficient to increase the MIC to >2500 µg/mL NaOCl, particularly in K. pneumoniae and P. aeruginosa. To determine the development of cross-resistance to antibiotics due to NaOCl exposure, the MICs for each antibiotic before and after the exposure of each strain to sublethal concentrations of NaOCl were compared. After overnight incubation with a sublethal concentration of NaOCl, a statistically significant increase in MIC was only observed for imipenem (p < 0.01). An investigation of the mechanism of cross-resistance by means of transcriptome analysis revealed that 1250 µg/mL of NaOCl-adapted K. pneumoniae and P. aeruginosa strains increased resistance to imipenem due to the increased expression of resistance-nodulation-cell division (RND) efflux pumps, such as AcrAB-TolC and MexAB/XY-OprM. Therefore, we suggest that exposure to NaOCl can influence the expression of RND efflux pump genes, contributing to imipenem cross-resistance.

Impact of Childhood Maltreatment on Cognitive Function and Its Relationship With Emotion Regulation in Young Adults.

Objectives: Childhood maltreatment can negatively impact cognitive development, including executive function, working memory, and processing speed. This study investigated the impact of childhood maltreatment on cognitive function in young adults using various measurements, including computerized tests, and their relationship with emotional dysregulation. Methods: We recruited 149 healthy individuals with and without maltreatment experiences and used the Wechsler Adult Intelligence Scale IV (WAIS-IV) and a computerized battery to analyze cognitive function. Results: Both the WAIS-IV and computerized tests revealed that individuals with a history of childhood maltreatment had decreased cognitive function, especially in terms of working memory and processing speed. These individuals tended to employ maladaptive emotion regulation strategies. Among cognitive functions, working memory is negatively related to maladaptive emotion regulation strategies such as catastrophizing. Conclusion: This study highlights the effects of childhood maltreatment on cognitive function in young adulthood. Moreover, the study suggests clinical implications of cognitive interventions for improving emotion regulation and cognitive function in individuals with a history of childhood maltreatment.

Effect of Temperature on Carbapenemase-Encoding Plasmid Transfer in Klebsiella pneumoniae.

Bacteria causing human infections can develop antibiotic resistance due to various factors. Temperature affects bacterial growth and gene transfer; however, studies exploring the association between the changes in local temperature and antibiotic resistance are limited. Here, we investigated the effects of local temperatures on the distribution of antibiotic resistance and transmission of carbapenemase-producing Enterobacterales using the data on Klebsiella pneumoniae from sentinel hospitals in eight regions included in the Korea Global Antimicrobial Resistance Surveillance System between 2017 and 2021. The resistance rates to most antibiotics, including carbapenems, varied significantly according to local temperature (p < 0.047), except for aminoglycosides. Conjugation experiments at various temperatures for strains encoding the carbapenemase gene on a plasmid revealed significant variation in the optimal conjugation temperatures for plasmids carrying blaKPC and blaNDM genes. The optimal conjugation temperatures demonstrating the highest stability for blaKPC- and blaNDM-carrying plasmids were 25 °C (p = 0.030) and 30 °C (p = 0.007), respectively. The stability of blaKPC-IncF was higher at 25 °C than that at 30 °C (p = 0.032) or 37 °C (p = 0.047), while blaKPC-IncX3 exhibited the lowest stability at 37 °C (p = 0.047). blaNDM-IncX3 was more stable at 30 °C than at 37 °C (p = 0.049). These findings suggest that the optimal temperature for carbapenemase gene transmission varied between 25 °C and 30 °C, indicating that warmer seasons promote the transfer of more antibiotic resistance-related genes and highlighting the importance of local temperature in the spread and transmission of plasmids carrying carbapenemases.

Struvite production from anaerobic digestate of piggery wastewater using ferronickel slag as a magnesium source.

This study aimed to fully recover ammonia contained at a high concentration in anaerobic digestate of piggery wastewater (ADPW) by forming struvite. As magnesium and phosphorus sources, ferronickel slag (FNS) and K2HPO4 were used, respectively. By leaching 200 g L-1 of FNS with 3.0 M H2SO4, 10,309 mg L-1 of magnesium ions were extracted, and this acid-leachate of FNS (FNSL) also contained 5965 mg L-1 of total iron. In order to simultaneously remove both high concentrations of organic matters in ADPW and iron in FNSL which were known to hinder struvite formation, the mixture of ADPW and FNSL was added with H2O2 at the H2O2/Fe molar ratio of 0.75 and pH 4.0. After Fenton reaction, removal efficiencies of COD and total iron reached 77.36% and 99.89%, respectively. Then COD and an iron-reduced mixture of ADPW and FNSL were added with K2HPO4 satisfying Mg:N:P molar ratio of 1.2:1:1.15 at pH 9.5 to produce struvite for 1 h. From 1 L of ADPW (2.21 g NH3-N), 0.65 L of FNSL (4.65 g Mg2+), and 5.63 g of PO4 3-P, 46.7 g of precipitates were obtained. Overall removal efficiencies of magnesium, NH3-N, and phosphorus were 98.59%, 94.25%, and 99.97%, respectively. Obtained precipitates were analysed by using XRD, XRF, SEM-EDX and found to be struvite with impurities of potassium and metals. Additionally, the economic feasibility of FNS was assessed by estimating chemical costs of various magnesium sources.

Non-line-of-sight-imaging using dynamic relay surfaces.

The non-line-of-sight (NLOS) imaging problem has attracted a lot of interest in recent years. The objective is to produce images of objects that are hidden around a corner, using the information encoded in the time-of-flight (ToF) of photons that scatter multiple times after incidence at a given relay surface. Most current methods assume a Lambertian, flat and static relay surface, with non-moving targets in the hidden scene. Here we show NLOS reconstructions for a relay surface that is non-planar and rapidly changing during data acquisition. Our NLOS imaging system exploits two different detectors to collect the ToF data; one pertaining to the relay surface and another one regarding the ToF information of the hidden scene. The system is then able to associate where the multiply-scattered photons originated from the relay surface. This step allows us to account for changing relay positions in the reconstruction algorithm. Results show that the reconstructions for a dynamic relay surface are similar to the ones obtained using a traditional non-dynamic relay surface.

Mitogen-Induced Interferon Gamma Production in Human Whole Blood: The Effect of Heat and Cations.

BACKGROUND: Interferon-gamma release assays (IGRAs) are blood tests used to measure the amount of interferon-γ (IFN-γ) released by T lymphocytes after stimulation by antigens specific for the diagnosis of latent tuberculosis infection. A mitogen serves as a positive control to assess the immune function in IGRAs. METHODS: This in vitro study was conducted to evaluate IFN-γ production by human whole blood stimulated with heat-treated and/or cation-supplemented phytohemagglutinin (PHA), concanavalin A (Con A) and pokeweed mitogen (PWM), using QuantiFERON-TB Gold Kit ELISA tests. RESULTS: The optimal concentrations of PWM, Con A and PHA for IGRAs were 2 µg/mL, 5 µg/mL and 10 µg/mL, respectively. The results showed that IFN-γ production in response to PWM was the highest and PHA was the lowest amount. The median values of three mitogens were in the following order: PWM≥Con A≥ positive control>>PHA-P>>negative control. PWM and PHA were heat stable, while Con A was heat sensitive. The mitogen response of lymphocytes to untreated or heat-treated PWM and heat-treated Con A was increased in 1 mM Ca2+-supplemented groups, whereas the response to heat-treated PHA was decreased. Exposure to 1 mM Mg2+ had no effect on untreated or heat-treated PWM, and a concentration of 1 mM Zn2+ inhibited the stimulation of un-treated PWM. We found that calcium supplementation improved the PWM-induced production of IFN-γ. CONCLUSION: Therefore, PWM is an appropriate mitogen for use as a positive control in IGRAs. It is a potential indicator of cytokine production in the diagnostic as well as research settings, and calcium supplementation improved stimulation.

Recovery of ammonia through struvite production using anaerobic digestate of piggery wastewater and leachate of sewage sludge ash.

Anaerobic digestate of piggery wastewater (ADPW) contains high concentrations of ammonia and phosphorus with unbalanced molar ratio. Thus, ammonia remains at a high level even after phosphorus is completely removed through struvite formation. In this study, both ammonia and phosphorus were recovered by adding leachate of sewage sludge ash (SSA) into ADPW. It was demonstrated that 11,600 mg L-1 of total phosphorus and 7266.7 mg L-1 of [Formula: see text]-P were extracted from SSA by using sulfuric acid at the H2SO4/SSA mass ratio of 0.35. ADPW and the leachate of SSA were mixed at the volumetric ratio of 1:1.29, and then struvite was formed at the molar ratio of 1.2 (Mg2+):1.0 ([Formula: see text]-P):1.0 (NH3-N). Removal efficiencies of ammonia and phosphorus were 91.95% and 99.65%, respectively. The obtained struvite was analyzed by various methods and was found to meet the Korean fertilizer standards, except for copper.

Interventions for Preventing Childhood Obesity with Smartphones and Wearable Device: A Protocol for a Non-Randomized Controlled Trial.

BACKGROUND: Childhood obesity is a critical health issue, both currently and for the foreseeable future. To prevent obesity, behavior changes are essential. Smartphones can be a good tool, as the number of child smartphone users is rapidly increasing. We have developed a mobile platform system named "HAPPY ME," which is a smartphone application coupled with a wearable device, designed to improve healthy behaviors to prevent childhood obesity. This study aimed to evaluate the effectiveness of obesity prevention among children 10-12 years of age using HAPPY ME. METHODS: A total of 1000 participants, all fifth and sixth graders from four schools, were assigned to either control or intervention groups by school. Students in the intervention group used HAPPY ME. The study comprises a safety test, a 12-week efficacy test, and a six-month follow-up test to determine the long-term effects of preventive intervention via the integrated service platform. The integrated service platform aims to facilitate child-parent-school participation, involving the child-parent mobile application, a child-teacher mobile web, and a school website. Primary outcome measures are behavioral changes, including healthy eating, increased physical activity, and fitness. Secondary outcome measures are changes in anthropometric parameters (body weight, height, body mass index z-score, and waist circumference), body mass index (BMI) percentiles (obesity rate), and psychological perceptions among participants. CONCLUSIONS: The results of this study will offer evidence of the effectiveness of a mobile platform service with a multi-component intervention program based on a comprehensive approach.

Structural and Kinetic Characteristics of 1,4-Dioxane-Degrading Bacterial Consortia Containing the Phylum TM7.

1,4-Dioxane-degrading bacterial consortia were enriched from forest soil (FS) and activated sludge (AS) using a defined medium containing 1,4-dioxane as the sole carbon source. These two enrichments cultures appeared to have inducible tetrahydrofuran/dioxane and propane degradation enzymes. According to qPCR results on the 16S rRNA and soluble di-iron monooxygenase genes, the relative abundances of 1,4-dioxane-degrading bacteria to total bacteria in FS and AS were 29.4% and 57.8%, respectively. For FS, the cell growth yields (Y), maximum specific degradation rate (Vmax), and half-saturation concentration (Km) were 0.58 mg-protein/mg-dioxane, 0.037 mg-dioxane/mg-protein∙h, and 93.9 mg/l, respectively. For AS, Y, Vmax, and Km were 0.34 mg-protein/mg-dioxane, 0.078 mg-dioxane/mg-protein∙h, and 181.3 mg/l, respectively. These kinetics data of FS and AS were similar to previously reported values. Based on bacterial community analysis on 16S rRNA gene sequences of the two enrichment cultures, the FS consortium was identified to contain 38.3% of Mycobacterium and 10.6% of Afipia, similar to previously reported literature. Meanwhile, 49.5% of the AS consortium belonged to the candidate division TM7, which has never been reported to be involved in 1,4-dioxane biodegradation. However, recent studies suggested that TM7 bacteria were associated with degradation of non-biodegradable and hazardous materials. Therefore, our results showed that previously unknown 1,4-dioxane-degrading bacteria might play an important role in enriched AS. Although the metabolic capability and ecophysiological significance of the predominant TM7 bacteria in AS enrichment culture remain unclear, our data reveal hidden characteristics of the TM7 phylum and provide a perspective for studying this previously uncultured phylotype.

A novel perchlorate- and nitrate-reducing bacterium, Azospira sp. PMJ.

A novel perchlorate-reducing bacterium (PCRB), PMJ, was isolated from the mixed liquor suspended solids in the aerobic tank of a wastewater treatment plant. The 16S ribosomal RNA (rRNA), perchlorate reductase, and chlorite dismutase gene sequences revealed that PMJ belonged to the genus Azospira. PMJ was removed high-strength (700 mg/L) perchlorate and also removed low-strength (≤50 mg/L) perchlorate below the detection limit (2 µg/L) when acetate was used as a sole and carbon source. The maximum specific perchlorate utilization rate, q max, was 0.96 mg ClO4 (-)/mg dry cell weight day, and the half-saturation constant, K S , was lower than 0.002 mg ClO4 (-)/L. PMJ also utilized inorganic electron donors [(H2, S(0), and Fe(II)] with perchlorate as an electron acceptor. Perchlorate reduction by PMJ was completely inhibited by oxygen and chlorate but was not inhibited by nitrate. In the presence of similar concentrations (100∼140 mg/L) of nitrate and perchlorate, PMJ simultaneously removed both electron acceptors. Therefore, it was concluded that the strains PMJ might possess separate pathways for perchlorate and nitrate reduction. These results indicated that Azospira sp. PMJ could be efficiently used for treating perchlorate-contaminated groundwater and wastewater because many of these water bodies are known to contain both perchlorate and nitrate. In addition, low K S value and autotrophic perchlorate reduction of PMJ might be useful to design the biological treatment systems.

Bacterial communities in the initial stage of marine biofilm formation on artificial surfaces.

Succession of bacterial communities during the first 36 h of biofilm formation in coastal water was investigated at 3 approximately 15 h intervals. Three kinds of surfaces (i.e., acryl, glass, and steel substratum) were submerged in situ at Sacheon harbor, Korea. Biofilms were harvested by scraping the surfaces, and the compositions of bacterial communities were analyzed by terminal restriction fragment length polymorphism (T-RFLP), and cloning and sequencing of 16S rRNA genes. While community structure based on T-RFLP analysis showed slight differences by substratum, dramatic changes were commonly observed for all substrata between 9 and 24 h. Identification of major populations by 16S rRNA gene sequences indicated that gamma-Proteobacteria (Pseudomonas, Acinetobacter, Alteromonas, and uncultured gamma-Proteobacteria) were predominant in the community during 0 approximately 9 h, while the ratio of alpha-Proteobacteria (Loktanella, Methylobacterium, Pelagibacter, and uncultured alpha-Proteobacteria) increased 2.6 approximately 4.8 folds during 24 approximately 36 h of the biofilm formation, emerging as the most predominant group. Previously, alpha-Proteobacteria were recognized as the pioneering organisms in marine biofilm formation. However, results of this study, which revealed the bacterial succession with finer temporal resolution, indicated some species of gamma-Proteobacteria were more important as the pioneering population. Measures to control pioneering activities of these species can be useful in prevention of marine biofilm formation.

Oceanobacillus caeni sp. nov., isolated from a Bacillus-dominated wastewater treatment system in Korea.

A Gram-positive, rod-shaped, spore-forming bacterium, strain S-11T, was isolated from the activated sludge of a Bacillus-dominated wastewater treatment system in South Korea and was characterized using a polyphasic approach in order to determine its taxonomic position. Cells (0.5-0.6 x 2.0-2.2 microm) were motile by means of a single subpolar flagellum. They bore ellipsoidal endospores that lay in a central position in swollen sporangia. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain S-11T was a member of the genus Oceanobacillus. 16S rRNA gene sequence similarity values and DNA-DNA relatedness of strain S-11T to the type strains of other Oceanobacillus species were less than 96.2 and 66.0 %, respectively. Strain S-11T showed distinct differences in the G+C content of the genomic DNA (33.6 mol%). The major cellular fatty acids were iso-C14 : 0, iso-C15 : 0, anteiso-C15 : 0 and iso-C16 : 0. The major isoprenoid quinone was MK-7. There were also some physiological differences in comparison with the type strains of Oceanobacillus species: tests for production of acetoin and acid production from dulcitol, erythritol, myo-inositol and sorbitol were positive. The results of DNA-DNA hybridization and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain S-11T from the six Oceanobacillus species and subspecies with validly published names. Strain S-11T therefore represents a novel species, for which the name Oceanobacillus caeni sp. nov. is proposed, with the type strain S-11T (=KCTC 13061T =CCUG 53534T =CIP 109363T).

Effects of resistance exercise and growth hormone administration at low doses on lipid metabolism in middle-aged female rats.

hGH (human growth hormone) is a key factor for metabolism as well as for growth. Lack of hGH usually increases LDL (low-density lipoprotein) while impairing exercise capacity and cardiac function [Amato G., Carella C., Fazio S., La Montagna G., Cittadini A., Sabatini D., Marciano-Mone C., Sacca L., and Bellastella A., 1993. Body composition, bone metabolism, and heart structure and function in growth hormone (GH)-deficient adults before and after GH replacement therapy at low doses. J. Clin. Endocrinol. Metab. 77, 1671-1676.]. It is still unclear, however, whether the administration of hGH to humans or animals has a synergic effects on body composition and the desired metabolic parameters with endurance resistance exercise. Therefore, the present study seeks to establish whether or not lipid metabolism is altered by both recombinant GH (growth hormone) and X (resistance exercise) in middle-aged female rats. GH administration resulted in greater weight gain compared with control and exercised animals, but the effect was reduced when combined with exercise. The increased body weight was largely due to increased muscle mass. Exercise did not result in any additional effect of GH on muscle mass. In the exercise group, hepatic HDL (high density lipoprotein) increased compared to the C (control group). The GX (growth hormone+exercise) group's serum and X group's kidney IGF-I (Insulin-like growth factor-I) concentration increased compared to the C group. In G and GX groups, serum insulin and leptin concentrations were higher than in the control, suggesting that GH may induce an insulin resistant state. Any gains in muscle mass were minimal and were not synergistic with exercise. These results suggest that hGH may not be useful for increasing performance in athletes and may induce and acquired insulin resistance.

Immune and nutrition status in elderly Koreans with hyperLDL-cholesterolemia.

Although the effects of nutrition and immune status on disease development have been investigated, little attention has been given to changes in immune function in the elderly vulnerable to coronary artery disease (CAD). Our objective was to evaluate the association between immune variables and CAD risk factors, and nutritional factors related to immune and lipid profiles in elderly Koreans (n = 90). The subjects were divided into three groups based on serum low-density lipoprotein cholesterol (LDL-cholesterol) level: risk (> or = 160 mg/dL), borderline (130-160 mg/dL), and control groups (< 130 mg/dL). Concanavalin A-induced lymphocyte proliferation rate and interleukin (IL)-2 secretion were significantly lower in the risk group than the control group. The subjects in the risk group showed the highest serum concentrations of proinflammatory mediators such as complement 3 (C3), IL-1beta, and IL-1 receptor antagonist (IL-1RA). The nutrient intake status of the subjects was generally satisfactory without differences among groups. IL-1RA concentration was negatively associated with intake of vitamin E and C3 was positively related to intake of Ca and Fe in the subjects with LDL-cholesterol > or = 130 mg/dL. This study suggests that elderly individuals with high serum LDL-cholesterol are in a mild chronic inflammation state and micronutrient status such as vitamin E, Ca, and Fe may relate to this state.