Impact of air temperature on occurrence of bath-related cardiac arrest.

ABSTRACT: The mortality of the bath-related cardiac arrest (BRCA) is extremely high. While air temperature is reported to be associated with the BRCA occurrence, it is unclear whether daily minimum temperatures or the difference between maximum and minimum air temperatures influences BRCA occurrence the most.A retrospective cohort study of adult patients was conducted between January 2015 and February 2020 at Hirosaki University Hospital Emergency Department. The following data were collected: age, sex, day of cardiac arrest event, location of the event, initial cardiac rhythm, presence of return of spontaneous circulation, and overall mortality (status at 1 month after cardiac arrest event). Based on the day of the event and the location in which the event occurred, daily minimum and maximum temperatures were obtained from the Japan Meteorological Agency database.A total of 215 eligible cardiac arrest cases were identified, including 25 cases of BRCA. Comparing BRCA and non-BRCA, initial shockable cardiac rhythm (4.0% vs 44.7%), presence of return of spontaneous circulation (8.0% vs 34.7%), and overall mortality (96.0% vs 71.6%) differed significantly (P < .05 each). Daily minimum and maximum temperatures showed no significant relationships with BRCA or non-BRCA. Daily minimum temperature was a risk factor of BRCA occurrence after adjusting for age and temperature difference (risk ratio, 0.937; 95% confidence interval, 0.882-0.995).Daily minimum temperature represents a potential risk factor for BRCA occurrence.

Produced ß-hydroxybutyrate after ß-hydroxy-ß-methylbutyrate (HMB) administration may contribute HMB function in mice.

ß-Hydroxy-ß-methylbutyrate (HMB) is an intermediate in the metabolism of the branched-chain amino acid leucine. HMB has several demonstrated effects on skeletal muscle function, some of which are contradictory. In addition, the effect of exogenous HMB intake on the levels of intermediate metabolites is not known. Therefore, we investigated changes in HMB metabolites after oral HMB administration in mice. First, ICR mice were treated with either distilled water or HMB (0.215 g/10 mL/kg). Sampling was performed at 0, 1, 6, 12, and 24 h after administration. Next, ICR mice were given distilled water or HMB (0.215 g/10 mL/kg/d) for 10 d. Mice given HMB shown a significant increase in liver ß-methylcrotonyl-CoA and increased ß-hydroxybutyrate in plasma and the gastrocnemius muscle 1 h after HMB administration. Mice administered HMB for 10 d showed significantly decreased food intake and body weight; however, the relative weight of the gastrocnemius muscle was significantly increased. These results may be attributed to an increase in ß-hydroxybutyrate resulting from exogenous HMB, since ß-hydroxybutyrate inhibits food intake and suppresses skeletal muscle catabolism. In conclusion, ß-hydroxybutyrate, a metabolite of HMB, was found to play an important role in the function of HMB.

Calibration-Curve-Locking Database for Semi-Quantitative Metabolomics by Gas Chromatography/Mass Spectrometry.

Calibration-Curve-Locking Databases (CCLDs) have been constructed for automatic compound search and semi-quantitative screening by gas chromatography/mass spectrometry (GC/MS) in several fields. CCLD felicitates the semi-quantification of target compounds without calibration curve preparation because it contains the retention time (RT), calibration curves, and electron ionization (EI) mass spectra, which are obtained under stable apparatus conditions. Despite its usefulness, there is no CCLD for metabolomics. Herein, we developed a novel CCLD and semi-quantification framework for GC/MS-based metabolomics. All analytes were subjected to GC/MS after derivatization under stable apparatus conditions using (1) target tuning, (2) RT locking technique, and (3) automatic derivatization and injection by a robotic platform. The RTs and EI mass spectra were obtained from an existing authorized database. A quantifier ion and one or two qualifier ions were selected for each target metabolite. The calibration curves were obtained as plots of the peak area ratio of the target compounds to an internal standard versus the target compound concentration. These data were registered in a database as a novel CCLD. We examined the applicability of CCLD for analyzing human plasma, resulting in time-saving and labor-saving semi-qualitative screening without the need for standard substances.

Metabolic alteration of Methylococcus capsulatus str. Bath during a microbial gas-phase reaction.

This study demonstrates the metabolic alteration of Methylococcus capsulatus (Bath), a representative bacterium among methanotrophs, in microbial gas-phase reactions. For comparative metabolome analysis, a bioreactor was designed to be capable of supplying gaseous substrates and liquid nutrients continuously. Methane degradation by M. capsulatus (Bath) was more efficient in a gas-phase reaction operated in the bioreactor than in an aqueous phase reaction operated in a batch reactor. Metabolome analysis revealed remarkable alterations in the metabolism of cells in the gas-phase reaction; in particular, pyruvate, 2-ketoglutarate, some amino acids, xanthine, and hypoxanthine were accumulated, whereas 2,6-diaminopimelate was decreased. Based on the results of metabolome analysis, cells in the gas-phase reaction seemed to alter their metabolism to reduce the excess ATP and NADH generated upon increased availability of methane and oxygen. Our findings will facilitate the development of efficient processes for methane-based bioproduction with low energy consumption.

Relationships between body composition and pulmonary function in a community-dwelling population in Japan.

Pulmonary diseases, including chronic obstructive pulmonary disease (COPD), are major chronic diseases that result in decreased pulmonary function. Relationships between body composition and pulmonary function have been reported. However, few epidemiological studies have used the visceral fat area (VFA) to measure body composition. This study aimed to examine the relationship between body composition and pulmonary function. A cross-sectional study was conducted between 2015 and 2016, using data obtained from 1,287 residents aged between 19 and 91 years living in the Iwaki area of Hirosaki City, a rural region in Aomori Prefecture, Japan. Pulmonary function was evaluated using the forced vital capacity (FVC) as a percentage of the predicted value (predicted FVC%) and the ratio of forced expiratory volume in one second (FEV1) to FVC. The measurements for evaluating body composition included the body fat percentage (BFP) of the whole body and trunk, skeletal muscle index (SMI), body mass index (BMI), VFA, waist circumference (WC) at the navel level, and waist-to-hip ratio (WHR). To adjust for potential confounders, Spearman's partial correlation analysis was used to examine the relationship between the measurements of body composition and pulmonary function. There were significant correlations between the predicted FVC% and the following parameters: BFP (whole body and trunk) in younger males; SMI in older males; WC, VFA, BMI, and SMI in younger females; and BFP (whole body and trunk) and VFA in older females. Contrastingly, WC and VFA in younger males and WC in younger females were correlated with the FEV1/FVC ratio. VFA was correlated with the FEV1/FVC ratio in younger males and predicted FVC% in older females. These findings suggest that visceral fat accumulation may increase the development of obstructive pulmonary disease in young males and accelerate the decline of pulmonary function (predicted FVC%) in older females.

Oral conditions and dysphagia in Japanese, community-dwelling middle- and older- aged adults, independent in daily living.

PURPOSE: Prevention, early detection and effective rehabilitation of dysphagia are important issues to be considered in an aging society. Previous studies have shown conflicting findings regarding the association between dysphagia and its potential risk factors, including age, malnutrition, oral conditions, lifestyle and medical history. Herein, we assessed the prevalence and association of dysphagia with potential risk factors in 50- to 79-year-old adults dwelling in a community in Japan. PATIENTS AND METHODS: In this study, there were 532 participants (185 males and 347 females). Participants who responded positively to the question "Do you sometimes choke on drinks/food such as tea and soup?" or those who presented with abnormal repetitive saliva swallowing test findings were diagnosed with dysphagia. The data collected from these participants included the following: number of teeth, occurrence of oral dryness, age, body mass index, serum albumin concentration, smoking, drinking and exercise habits, presence of diseases, such as diabetes mellitus and hypertension, and questions from the Mini-Mental State Examination. RESULTS: Dysphagia was observed in 33 males (17.8%) and 76 females (21.9%). To explore the effect of the potential risk factors on the prevalence of dysphagia, a model was built by multivariate logistic regression analysis. Using the forced entry method, oral dryness (odds ratio [OR] =3.683 and P=0.003 in males; OR =1.797 and P=0.032 in females) and the number of teeth (OR =0.946 and P=0.038 in males) were found to be significantly related to dysphagia. CONCLUSION: This cross-sectional study demonstrated associations between oral conditions and dysphagia. Factors such as oral dryness and number of teeth may contribute to dysphagia more so than aging, lifestyle and comorbidity in community-dwelling adults over the age of 50.

Synthetic metabolic bypass for a metabolic toggle switch enhances acetyl-CoA supply for isopropanol production by Escherichia coli.

Almost all synthetic pathways for biofuel production are designed to require endogenous metabolites in glycolysis, such as phosphoenolpyruvate, pyruvate, and acetyl-CoA. However, such metabolites are also required for bacterial cell growth. To reduce the metabolic imbalance between cell growth and target chemical production, we previously constructed a metabolic toggle switch (MTS) as a conditional flux redirection tool controlling metabolic flux of TCA cycle toward isopropanol production. This approach succeeded to improve the isopropanol production titer and yield while ensuring sufficient cell growth. However, excess accumulation of pyruvate, the precursor for acetyl-CoA synthesis, was also observed. In this study, for efficient conversation of pyruvate to acetyl-CoA (pyruvate oxidation), we designed a synthetic metabolic bypass composed of poxB and acs with the MTS for acetyl-CoA supply from the excess pyruvate. When this designed bypass was expressed at the appropriate expression level associated with the conditional metabolic flux redirection, pyruvate accumulation was prevented, and the isopropanol production titer and yield were improved. Final isopropanol production titer of strain harboring MTS with the synthetic metabolic bypass improved 4.4-fold compared with strain without metabolic flux regulation, and it was 1.3-fold higher than that of strain harboring the conventional MTS alone. Additionally, glucose consumption was also improved 1.7-fold compared with strain without metabolic flux regulation. On the other hand, introduction of the synthetic metabolic bypass alone showed no improvement in isopropanol production and glucose consumption. These results showed that the improvement in bio-production process caused by synergy between the MTS and the synthetic metabolic bypass.

Self-induced metabolic state switching by a tunable cell density sensor for microbial isopropanol production.

Chemicals production by engineered microorganisms often requires induction of target gene expression at an appropriate cell density to reduce conflict with cell growth. The lux system in Vibrio fischeri is a well-characterized model for cell density-dependent regulation of gene expression termed quorum sensing (QS). However, there are currently no reports for application of the lux system to microbial chemical production. Here, we constructed a synthetic lux system as a tunable cell density sensor-regulator using a synthetic lux promoter and a positive feedback loop in Escherichia coli. In this system, self-induction of a target gene expression is driven by QS-signal, and its threshold cell density can be changed depending on the concentration of a chemical inducer. We demonstrate auto-redirection of metabolic flux from central metabolic pathways toward a synthetic isopropanol pathway at a desired cell density resulting in a significant increase in isopropanol production.

Direct isopropanol production from cellobiose by engineered Escherichia coli using a synthetic pathway and a cell surface display system.

Efficient bio-production from lignocellulosic biomass is required for the purpose of developing an inexpensive, practical bio-refinery process. As one approach to address this problem, we genetically engineered Escherichia coli to produce isopropanol directly from cellobiose via the cellobiose degradation by Beta-Glucosidase (BGL) on the cell surface. First, we investigated the cellobiose consumption of two E. coli strains with the BGL protein from Thermobifida fusca YX (Tfu0937) fused to the anchor protein Blc (Tfu0937/Blc) using different fusion sites. Next, we introduced the synthetic pathway for isopropanol production into those strains and compared their isopropanol production in the presence of glucose. Based on the results of these assays, TA212/pTA411, which was introduced Tfu-Blc fused protein expression system and the synthetic pathway for isopropanol production, was selected for the directly isopropanol production from cellobiose. TA212/pTA411 produced 69.0±11.6mM isopropanol at 21h of fermentation, whereas TA212/pTA147, which did not introduced the BGL/anchor fused protein but was introduced the synthetic pathway for isopropanol production, showed no cellobiose consumption and no isopropanol production during fermentation. To our knowledge, this is the first report of the production of a bio-product from cellobiose using E. coli.