The Blood Pressure Control Effect of the Sodium-Restricted Dietary Approaches to Stop Hypertension Diet: A Systematic Review.

The Dietary Approaches to Stop Hypertension (DASH) diet is highly effective in controlling blood pressure (BP). Although sodium restriction is not a primary focus within the DASH diet, it is recommended that it be added to control BP. Therefore, we aimed to systematically review the characteristics and BP-lowering effects of sodium-restricted DASH diet interventions. We searched 13 databases, namely, MEDLINE, Embase, Cochrane Central Register of Controlled Trials, KoreaMed, KISS, KMbase, RISS, CINAHL, Scopus, ClinicalTrials.gov, Grey Literature Report, OpenGrey, and PQDT Global, for articles published through May 2023. Randomised controlled trials assessing the BP-lowering effect of the sodium-restricted DASH diet in adults aged 18 years and older were included. The study protocol was registered in the PROSPERO registry (CRD42023409996). The risk of bias in the included studies was also assessed. Nine articles were included in this review. Interventions were categorised into three types: feeding, provision, and education, and the study results were compared by intervention type. BP was significantly reduced in two of the three feeding studies, one of the three provisional studies, and none of the educational studies. In eight studies, effect sizes varied among both systolic BP (-7.7 to -2.4) and diastolic BP (-8.3 to 0.1). Six studies showed an overall high risk of bias. In conclusion, sodium-restricted DASH may have beneficial effects on BP control. Additionally, compared to control interventions, feeding interventions appeared to have a greater BP-lowering effect. Further high-quality studies are needed to improve the quality of the evidence.

Enhancing Precision in L-band Electron Paramagnetic Resonance Tooth Dosimetry: Incorporating Digital Image Processing and Radiation Therapy Plans for Geometric Correction.

ABSTRACT: Following unforeseen exposure to radiation, quick dose determination is essential to prioritize potential patients that require immediate medical care. L-band electron paramagnetic resonance tooth dosimetry can be efficiently used for rapid triage as this poses no harm to the human incisor, although geometric variations among human teeth may hinder accurate dose estimation. Consequently, we propose a practical geometric correction method using a mobile phone camera. Donated human incisors were irradiated with calibrated 6-MV photon beam irradiation, and dose-response curves were developed by irradiation with a predetermined dose using custom-made poly(methyl methacrylate) slab phantoms. Three radiation treatment plans for incisors were selected and altered to suit the head phantom. The mean doses on tooth structures were calculated using a commercial treatment planning system, and the electron paramagnetic resonance signals of the incisors were measured. The enamel area was computed from camera-acquired tooth images. The relative standard uncertainty was rigorously estimated both with and without geometric correction. The effects on the electron paramagnetic resonance signal caused by axial and rotational movements of tooth samples were evaluated through finite element analysis. The mean absolute deviations of mean doses both with and without geometric correction showed marginal improvement. The average relative differences without and with geometric correction significantly decreased from 21.0% to 16.8% (p = 0.01). The geometric correction method shows potential in improving dose precision measurement with minimal delay. Furthermore, our findings demonstrated the viability of using treatment planning system doses in dose estimation for L-band electron paramagnetic resonance tooth dosimetry.

Complementation of reducing power for 5-hydroxyvaleric acid and 1,5-pentanediol production via glucose dehydrogenase in Escherichia coli whole-cell system.

One of the key intermediates, 5-hydroxyvaleric acid (5-HV), is used in the synthesis of polyhydroxyalkanoate monomer, δ-valerolactone, 1,5-pentanediol (1,5-PDO), and many other substances. Due to global environmental problems, eco-friendly bio-based synthesis of various platform chemicals and key intermediates are socially required, but few previous studies on 5-HV biosynthesis have been conducted. To establish a sustainable bioprocess for 5-HV production, we introduced gabT encoding 4-aminobutyrate aminotransferase and yqhD encoding alcohol dehydrogenase to produce 5-HV from 5-aminovaleric acid (5-AVA), through glutarate semialdehyde in Escherichia coli whole-cell reaction. As, high reducing power is required to produce high concentrations of 5-HV, we newly introduced glucose dehydrogenase (GDH) for NADPH regeneration system from Bacillus subtilis 168. By applying GDH with D-glucose and optimizing the parameters, 5-HV conversion rate from 5-AVA increased from 47% (w/o GDH) to 82% when using 200 mM (23.4 g/L) of 5-AVA. Also, it reached 56% conversion in 2 h, showing 56 mM/h (6.547 g/L/h) productivity from 200 mM 5-AVA, finally reaching 350 mM (41 g/L) and 14.6 mM/h (1.708 g/L/h) productivity at 24 h when 1 M (117.15 g/L) 5-AVA was used. When the whole-cell system with GDH was expanded to produce 1,5-PDO, its production was also increased 5-fold. Considering that 5-HV and 1,5-PDO production depends heavily on the reducing power of the cells, we successfully achieved a significant increase in 5-HV and 1,5-PDO production using GDH.

Enhanced Dosimetric Accuracy Using Quality Factor Compensation Method for In Vivo Electron Paramagnetic Resonance Tooth Dosimetry.

ABSTRACT: We aim to develop a dose assessment method compensating for quality factors (Q factor) observed during in vivo EPR tooth dosimetry. A pseudo-in-vivo phantom made of tissue-equivalent material was equipped with one each of four extracted human central incisors. A range of Q factors was measured at tooth-depths of -2, 0, and 2 mm in the pseudo-in-vivo phantom. In addition, in vivo Q factors were measured from nine human volunteers. For the dose-response data, the above four sample teeth were irradiated at 0, 1, 2, 5, and 10 Gy, and the radiation-induced signals were measured at the same tooth-depths using an in vivo EPR tooth dosimetry system. To validate the method, the signals of two post-radiotherapy patients and three unirradiated volunteers were measured using the same system. The interquartile range of the Q factors measured in the pseudo-in-vivo phantom covered that observed from the human volunteers, which implied that the phantom represented the Q factor distribution of in vivo conditions. The dosimetric sensitivities and background signals were decreased as increasing the tooth-depth in the phantom due to the decrease in Q factors. By compensating for Q factors, the diverged dose-response data due to various Q factors were converged to improve the dosimetric accuracy in terms of the standard error of inverse prediction (SEIP). The Q factors of patient 1 and patient 2 were 98 and 64, respectively, while the three volunteers were 100, 92, and 99. The assessed doses of patient 1 and patient 2 were 2.73 and 12.53 Gy, respectively, while expecting 4.43 and 13.29 Gy, respectively. The assessed doses of the unirradiated volunteers were 0.53, 0.50, and - 0.22 Gy. We demonstrated that the suggested Q factor compensation could mitigate the uncertainty induced by the variation of Q factors.

Frequency-fixed motion compensation system for in-vivo electron paramagnetic resonance tooth dosimetry.

This article describes the design process for a motion compensation system that can suppress the spectral distortion caused by human motion and breathing during in-vivo electron paramagnetic resonance (EPR) spectroscopy on an intact incisor. The developed system consists of two elements: an electronically controlled tunable resonator and an automatic control circuit (ACC). The resonator can modify the resonant frequency and impedance by tuning and matching the voltage, while the ACC can generate a feedback signal using phase-sensitive detection (PSD). The signal is transferred into the resonator to maintain the critical coupling state. The tunable frequency range of the resonator was measured at over 10 MHz, offering approximately eight times the required range. The bandwidth of the resonator fluctuated in a negligible range (0.14% relative standard error) following the resonant frequency. With the feedback signal on, in-vivo EPR measurements were demonstrated to be a stable baseline with 35% higher signal-to-noise ratio (SNR). When one incisor sample was irradiated by an X-ray instrument, the EPR signal responses to the absorbed doses of 0-10 Gy exhibited high linearity (R2 = 0.994). In addition, the standard error of inverse prediction was estimated to be 0.35 Gy. The developed system achieved a discrimination ability of 2 Gy, which is required for triage in large-scale radiation accidents. Moreover, the compensation is fully automated, meaning that the system can be operated with simple training in an emergency.

Developed and emerging 1,4-butanediol commercial production strategies: forecasting the current status and future possibility.

1,4-Butanediol (1,4-BDO) is a valuable industrial chemical that is primarily produced via several energy-intensive petrochemical processes based on fossil-based raw materials, leading to issues related to: non-renewability, environmental contamination, and high production costs. 1,4-BDO is used in many chemical reactions to develop a variety of useful, valuable products, such as: polyurethane, Spandex intermediates, and polyvinyl pyrrolidone (PVP), a water-soluble polymer with numerous personal care and pharmaceutical uses. In recent years, to satisfy the growing need for 1,4-BDO, there has been a major shift in focus to sustainable bioproduction via microorganisms using: recombinant strains, metabolic engineering, synthetic biology, enzyme engineering, bioinformatics, and artificial intelligence-guided algorithms. This article discusses the current status of the development of: various chemical and biological production techniques for 1,4-BDO, advances in biological pathways for 1,4-BDO biosynthesis, prospects for future production strategies, and the difficulties associated with environmentally friendly and bio-based commercial production strategies.

Dietary behavior and its influencing factors among experienced shiftwork nurses: a secondary analysis.

PURPOSE: This study investigated the dietary behavior of experienced shiftwork nurses and aimed to identify factors related to dietary behavior. METHODS: This study was a secondary analysis based on the Shift Work Nurses' Health and Turnover study (2018-2021) among Korean nurses. In total, 247 experienced (>12 months) shiftwork nurses were included in this study. The participants' dietary behavior, depression, level of occupational stress, fatigue, physical activity, and general characteristics were measured. Descriptive statistics, Pearson correlation coefficients, independent t-test, one-way analysis of variance, the Kruskal-Wallis test, and multiple regression analysis were conducted. RESULTS: The dietary behavior score of the participants using the Mini-Dietary Assessment Index was 29.35±5.67. Thirty percent of the participants were depressed, the participants experienced moderate occupational stress, and 74.1% of the participants engaged in an inadequate amount of physical activity. The factors influencing shiftwork nurses' dietary behavior were having child(ren) (ß=.16, p=.027), depression (ß=-.13, p=.032), level of occupational stress related to occupational climate (ß=-.13, p=.035), and an inadequate amount of physical activity (ß=-.17, p=.006). These factors explained 10.4% of the variance in experienced shiftwork nurses' dietary behavior scores. CONCLUSION: Experienced nurses with child(ren) tended to have healthier diets. However, a higher level of occupational stress related to occupational climate, depression, and engaging in an inadequate amount of physical activity were associated with a higher risk of having an unhealthy diet. Therefore, strategies are needed to encourage physical activity and alleviate adverse occupational climate and depression among experienced nurses.

Recent trends in the modification of polyphenolic compounds using hydroxylation and glycosylation.

Polyphenols are bioactive molecules that are used in therapeutics. Polyphenol hydroxylation and glycosylation have been shown to increase their bioavailability, solubility, bioactivity, and stability for use in various applications. Ortho-hydroxylation of polyphenols using tyrosinase allows high selectivity and yield without requiring a cofactor, while meta- and para-hydroxylation of polyphenols are mediated by site-specific hydroxylases and cytochrome P450s, although these processes are somewhat rare. O-glycosylation of polyphenols proceeds further after hydroxylation. The O-glycosylation reaction typically requires nucleotide diphosphate (NDP) sugar. However, amylosucrase (AS) has emerged as a promising enzyme for polyphenol glycosylation in large-scale production without requiring NDP-sugar. Overall, this review describes recent findings on the enzymatic mechanisms, enzyme engineering, and applications of enzymatic reactions.

Enhanced production of bio-indigo in engineered Escherichia coli, reinforced by cyclopropane-fatty acid-acyl-phospholipid synthase from psychrophilic Pseudomonas sp. B14-6.

Indigo dye is an organic compound with a distinctive blue color. Most of the indigo currently used in industry is produced via chemical synthesis, which generates a large amount of wastewater. Therefore, several studies have recently been conducted to find ways to produce indigo eco-friendly using microorganisms. Here, we produced indigo using recombinant Escherichia coli with both an indigo-producing plasmid and a cyclopropane fatty acid (CFA)-regulating plasmid. The CFA-regulating plasmid contains the cfa gene, and its expression increases the CFA composition of the phospholipid fatty acids of the cell membrane. Overexpression of cfa showed cytotoxicity resistance of indole, an intermediate product formed during the indigo production process. This had a positive effect on indigo production and cfa originated from Pseudomonas sp. B 14-6 was used. Optimal conditions for indigo production were determined by adjusting the expression strain, culture temperature, shaking speed, and isopropyl ß-D-1-thiogalactopyranoside concentration. Treatment with Tween 80 at a particular concentration to increase the permeability of the cell membrane had a positive effect on indigo production. The strain with the CFA plasmid produced 4.1 mM of indigo after 24 h of culture and produced 1.5-fold higher indigo than the control strain without the CFA plasmid that produced 2.7 mM.

Enhanced isobutanol production using engineered E. coli and B. subtilis host by UV-induced mutation.

Recombinant Escherichia coli and Bacillus subtilis strains were engineered by simultaneous chemical and ultraviolet-induced random mutagenesis to enhance bio-alcohol production. Our study investigated the bio-alcohol production of six variants of E. coli (EM1-6) and B. subtilis mutants (BM1-6). The induced mutation in the EM variants increased isobutanol (C4 alcohol) production most effectively, whereas pH adjustment and additional l-valine feeding increased isobutanol production by the BM variants. In contrast, pH adjustment or l-valine addition negatively affected isobutanol production by the EM variants. The highest titer of 5.07 g/L of isobutanol from a 40 g/L yeast extract medium (YEM) was achieved by the EM1 variant, whereas 0.57 g/L of isobutanol from YEM supplemented with 5 g/L of l-valine was obtained from the BM5 variant. These results can be applied in further research on engineering production hosts and improving production titers to utilize heterogenous bioresources in the future.

Anger, a Result and Cause of Stroke: A Narrative Review.

Post-stroke mood and emotional disturbances are frequent and diverse in their manifestations. Among them, post-stroke depression is the best known. Although post-stroke anger (PSA) has been studied relatively less, it can be as frequent as depression. Manifestations of PSA range from overt aggressive behaviors (including hitting or hurting others) to becoming irritable, impulsive, hostile, and less tolerable to family members. The possible pathophysiological mechanisms of PSA include neurochemical dysfunction due to brain injury, frustration associated with neurological deficits or unfavorable environments, and genetic predisposition. PSA causes distress in both patients and their caregivers, negatively influences the patient's quality of life, and increases the burden on caregivers. It can be treated or prevented using various methods, including pharmacological therapies. In addition, anger or hostility may also be a risk or triggering factor for stroke. The hazardous effects of anger may be mediated by other risk factors, including hypertension or diabetes mellitus. The identification of anger as a result or cause of stroke is important because strategic management of anger may help improve the patient's quality of life or prevent stroke occurrence. In this narrative review, we describe the phenomenology, prevalence, factors or predictors, relevant lesion locations, and pharmacological treatment of PSA. We further describe the current evidence on anger as a risk or triggering factor for stroke.

Controlling catabolite repression for isobutanol production using glucose and xylose by overexpressing the xylose regulator.

Using lignocellulosic biomass is immensely beneficial for the economical production of biochemicals. However, utilizing mixed sugars from lignocellulosic biomass is challenging because of bacterial preference for specific sugar such as glucose. Although previous studies have attempted to overcome this challenge, no studies have been reported on isobutanol production from mixed sugars in the Escherichia coli strain. To overcome catabolite repression of xylose and produce isobutanol using mixed sugars, we applied the combination of three strategies: (1) deletion of the gene for the glucose-specific transporter of the phosphotransferase system (ptsG); (2) overexpression of glucose kinase (glk) and glucose facilitator protein (glf); and (3) overexpression of the xylose regulator (xylR). xylR gene overexpression resulted in 100% of glucose and 82.5% of xylose consumption in the glucose-xylose mixture (1:1). Moreover, isobutanol production increased by 192% in the 1:1 medium, equivalent to the amount of isobutanol produced using only glucose. These results indicate the effectiveness of xylR overexpression in isobutanol production. Our findings demonstrated various strategies to overcome catabolite repression for a specific product, isobutanol. The present study suggests that the selected strategy in E. coli could overcome the major challenge using lignocellulosic biomass to produce isobutanol.

Health problems, turnover intention, and actual turnover among shift work female nurses: Analyzing data from a prospective longitudinal study.

AIMS: This study investigated health problems, turnover intention, and actual turnover among shift work nurses. While turnover intention is often used as a proxy variable for turnover, the relationship between these variables requires clarification. This study tested for relevant associations using prospective longitudinal data with a time lag of 12 months. We also tested for associations between health problems (sleep disturbance, fatigue, and depression) and turnover intentions/turnover, with a focus on the mediating role of turnover intention. METHODS: This study conducted a secondary analysis of data from the Shift Work Nurses' Health and Turnover project, which is a prospective longitudinal cohort study. We analyzed health problems, turnover intention, and actual turnover. The data were analyzed via descriptive statistics, the Pearson's chi-squared test, independent t-test, univariable logistic regression, multiple logistic regression, and causal mediation. RESULTS: Participants included 491 shift work female nurses. Of these, 112 (22.8%) had turnover intention, while 38 (7.7%) left their jobs within the 12-month period of investigation. Of the 112 with turnover intention, 22 left their jobs (OR 5.68. 95% CI 2.84-11.36). The logistic regression analysis showed that sleep disturbance and fatigue were associated with turnover intentions and actual turnover, while depression was only associated with turnover intention. The causal mediation analysis showed that turnover intention mediated the relationship between health problems (sleep disturbance and fatigue) and actual turnover (sleep disturbance OR 1.31, 95%CI = 1.02-1.60; fatigue OR 2.11, 95%CI = 1.50-2.68); sleep disturbance had a natural direct effect on actual turnover (OR 2.66, 95%CI,2.07-3.21). CONCLUSION: Turnover intention strongly predicted actual turnover. Sleep disturbances may result in turnover, even in cases without existing turnover intention. These findings highlight the need for early interventions aimed at preventing and alleviating sleep disturbances for shift work female nurses.

Constructing multi-enzymatic cascade reactions for selective production of 6-bromoindirubin from tryptophan in Escherichia coli.

6-Bromoindirubin (6BrIR), found in Murex sea snails, is a precursor of indirubin-derivatives anticancer drugs. However, its synthesis remains limited due to uncharacterized biosynthetic pathways and difficulties in site-specific bromination and oxidation at the indole ring. Here, we present an efficient 6BrIR production strategy in Escherichia coli by using four enzymes, that is, tryptophan 6-halogenase fused with flavin reductase Fre (Fre-L3-SttH), tryptophanase (TnaA), toluene 4-monooxygenase (PmT4MO), and flavin-containing monooxygenase (MaFMO). Although most indole oxygenases preferentially oxygenate the electronically active C3 position of indole, PmT4MO was newly characterized to perform C2 oxygenation of 6-bromoindole with 45% yield to produce 6-bromo-2-oxindole. In addition, 6BrIR was selectively generated without indigo and indirubin byproducts by controlling the reducing power of cysteine and oxygen supply during the MaFMO reaction. These approaches led to 34.1 mg/L 6BrIR productions, making it possible to produce the critical precursor of the anticancer drugs only from natural ingredients such as tryptophan, NaBr, and oxygen.

Finding of novel polyhydroxybutyrate producer Loktanella sp. SM43 capable of balanced utilization of glucose and xylose from lignocellulosic biomass.

Polyhydroxybutyrate (PHB) is a potential substitute for plastics derived from fossil fuels, owing to its biodegradable and biocompatible properties. Lignocellulosic biomass could be used to reduce PHB production costs; however, the co-utilization of sugars, such as glucose and xylose, without catabolite repression is a difficult problem to be solved. Here, we selected a novel Loktanella sp. SM43 from a marine environment and optimized the conditions for PHB production. Loktanella sp. SM43 showed high PHB production (66.5% content) from glucose. When glucose and xylose were used together, this strain showed high utilization of both substrates compared to other high PHB-producers such as Halomonas sp. and Cupriavidus necator, which showed glucose preference. Loktanella sp. SM43 showed high growth and PHB production with lignocellulosic hydrolysates. When pine tree hydrolysates were used, PHB production was the highest at 3.66 ± 0.01 g/L, followed by Miscanthus (3.46 ± 0.09 g/L) and barley straw hydrolysate (3.36 ± 0.36 g/L). Overall, these results reveal the potential of Loktanella sp. SM43 to produce PHB using various lignocellulosic hydrolysates as feedstock and the first systematic study for PHB production with Loktanella sp. The approach of screening novel strains is a strategy to overcome co-utilization of sugars without genetic engineering.

One-Step RT-qPCR for Viral RNA Detection Using Digital Analysis.

The rapid detection of viruses is becoming increasingly important to prevent widespread infections. However, virus detection via reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is time-consuming, as it involves independent nucleic acid extraction and complementary DNA synthesis. This process limits the potential for rapid diagnosis and mass analysis, which are necessary to curtail viral spread. In this study, a simple and rapid thermolysis method was developed to circumvent the need for extraction and purification of viral RNA. The developed protocol was applied to one-chip digital PCR (OCdPCR), which allowed thermolysis, RT, and digital PCR in a single unit comprising 20,000 chambers of sub-nanoliter volume. Two viruses such as tobacco mosaic virus and cucumber mosaic virus were tested as model viral particles. First, the temperature, exposure time, and template concentration were optimized against tobacco mosaic viral particles, and the most efficient conditions were identified as 85°C, 5 min, and 0.01 µg/nL with a cycle threshold of approximately 33. Finally, the OCdPCR analysis yielded 1,130.2 copies/µL using 10-2 µg/nL of viral particles in a 30 min thermolysis-RT reaction at 70°C. This novel protocol shows promise as a quick, accurate, and precise method for large-scale viral analysis in the future.

Quantum dot synthesis from waste biomass and its applications in energy and bioremediation.

Quantum dots (QDs) are getting special attention due to their commendable optical properties and applications. Conventional metal-based QDs have toxicity and non-biodegradability issues, thus it becomes necessary to search for renewable precursor molecules for QDs synthesis. In recent years, biomass-based carbon rich QDs (CQDs) have been introduced which are mainly synthesised via carbonization (pyrolysis and hydrothermal treatment). These CQDs offered higher photostability, biocompatibility, low-toxicity, and easy tunability for physicochemical properties. Exceptional optical properties become a point of attraction for its multifaceted applications in various sectors like fabrication of electrodes and solar cells, conversion of solar energy to electricity, detection of pollutants, designing biosensors, etc. In recent years, a lot of work has been done in this field. This article will summarize these advancements along in a special context to biomass-based QDs and their applications in energy and the environment.

Finding of novel lactate utilizing Bacillus sp. YHY22 and its evaluation for polyhydroxybutyrate (PHB) production.

Polyhydroxyalkanoates (PHAs) and their derivatives are biopolymers that have the potential of replacing petroleum-based plastics and can be produced and degraded via bacterial metabolism. However, there are only a few studies on polyhydroxybutyrate (PHB) production using lactate, one of the major waste organic acids that could be implemented in the production of polylactic acid (PLA). Herein, we screened and characterized the PHA-producing microbial strains isolated from saltern soil from Docho Island (South Korea). Among the 24 identified microorganisms that can use lactate as a carbon source, Bacillus sp. YHY22, a newly reported strain, produced the highest amount of PHB: 4.05 g/L with 6.25 g/L dry cell weight, which is 64.7% PHB content under optimal production conditions. Bacillus sp. YHY22 could form the poly(3-hydroxybutyrate-co-3-hydroxyvalerate) copolymer with propionate addition. Moreover, Bacillus sp. YHY22 produced PHB in non-sterilized 2% lactate and 8% NaCl marine broth culture medium, suggesting that its production can occur in high salinity media without additional sterilization steps, rendering fermentation cost- and time-efficient.

Gamma aminobutyric acid (GABA) production in Escherichia coli with pyridoxal kinase (pdxY) based regeneration system.

Gamma-aminobutyric acid (GABA) is a non-proteinogenic amino acid act as a major neurotransmitter inhibitor in the nervous system of mammals. It also used as a precursor of bioplastics synthesis such as N-methylpyrolidone and polyamide 4. Chemical-based synthesis methods have many environmental-related issues, so efforts have been made to develop biosynthetic methods to produce GABA. Glutamate decarboxylase (GAD) transforms L-glutamate to GABA using pyridoxal 5'-phosphate (PLP) as a cofactor. Bioconversion of GABA with whole cells overexpressing the glutamate decarboxylase has advantages of fewer byproducts and rapid reaction. However, there is a bottleneck in the whole-cell bioconversion system i.e., higher GABA production require a large amount of cofactor PLP which make the process costly. Therefore, pyridoxal kinase (PdxY) able to regenerate PLP was introduced in the whole-cell system to construct a new GABA producing system. Culture and reaction conditions were optimized, and 100% conversion of 0.6 M MSG was obtained. This study reports that a competitive level of GABA production could be achieved without supplying additional PLPs.

Relationship between occupational stress, sleep disturbance, and presenteeism of shiftwork nurses.

PURPOSE: This study aimed to determine the relationships between occupational stress, sleep disturbance, and presenteeism in shiftwork nurses in South Korea. DESIGN: This cross-sectional study used survey data from 442 shiftwork nurses at two hospitals in South Korea. Data were collected between March 2018 and April 2020. METHODS: A self-reported questionnaire was used to assess shiftwork nurses' demographic and job-related information, presenteeism, occupational stress, and sleep disturbance. Data were analyzed using descriptive statistics, multiple regression, and the PROCESS macro. FINDINGS: The mean presenteeism score was 39.52. Multiple regression analysis revealed that job insecurity, interpersonal conflict, occupational climate, lack of reward, and job demand are significantly associated with presenteeism. Sleep disturbance was related to presenteeism and had a moderating effect on the relationship between occupational stress and presenteeism. CONCLUSIONS: This study indicates that proper occupational climate, positive interpersonal relationships, and adequate sleep can reduce shiftwork presenteeism. Therefore, individual and organizational efforts to alleviate occupational stress and sleep disturbances are essential. CLINICAL RELEVANCE: Organizational support is needed to maintain a positive occupational climate and interpersonal relationships and ameliorate sleep disturbance among shiftwork nurses.