Importance of Intracellular Energy Status on High-Hydrostatic-Pressure Inactivation of sake Yeast Saccharomyces cerevisiae

The HHP inactivation behaviors of Niigata sake yeast Saccharomyces cerevisiae strain S9arg and its aerobic respiratory-deficient mutant strains were investigated after cultivating them in a YPD media containing 2% to 15% glucose, as well as in moromi mash, in a laboratory-scale sake brewing process. The piezotolerance of strain S9arg, shown after cultivation in a YPD medium containing 2% glucose, decreased to become piezosensitive with increasing glucose concentrations in YPD media. In contrast, the piezosensitivity of a mutant strain UV1, shown after cultivation in the YPD medium containing 2% glucose, decreased to become piezotolerant with increasing glucose concentrations in the YPD medium. The intracellular ATP concentrations were analyzed for an S. cerevisiae strain with intact aerobic respiratory ability, as well as for strain UV1. The higher concentration of ATP after cultivation suggested a higher energy status and may be closely related to higher piezotolerance for the yeast strains. The decreased piezotolerance of strain S9arg observed after a laboratory-scale sake brewing test may be due to a lower energy status resulting from a high glucose concentration in moromi mash during the early period of brewing, as well as a lower aeration efficiency during the brewing process, compared with cultivation in a YPD medium containing 2% glucose.

Isolation and physiological properties of methanogenic archaea that degrade tetramethylammonium hydroxide

Tetramethylammonium hydroxide (TMAH) is a known toxic chemical used in the photolithography process of semiconductor photoelectronic processes. Significant amounts of wastewater containing TMAH are discharged from electronic industries. It is therefore attractive to apply anaerobic treatment to industrial wastewater containing TMAH. In this study, a novel TMAH-degrading methanogenic archaeon was isolated from the granular sludge of a psychrophilic upflow anaerobic sludge blanket (UASB) reactor treating synthetic wastewater containing TMAH. Although the isolate (strain NY-STAYD) was phylogenetically related to Methanomethylovorans uponensis, it was the only isolated Methanomethylovorans strain capable of TMAH degradation. Strain NY-STAYD was capable of degrading methylamine compounds, similar to the previously isolated Methanomethylovorans spp. While the strain was able to grow at temperatures ranging from 15 to 37°C, the cell yield was higher at lower temperatures. The distribution of archaeal cells affiliated with the genus Methanomethylovorans in the original granular sludge was investigated by fluorescence in situ hybridization (FISH) using specific oligonucleotide probe targeting 16S rRNA. The results demonstrated that the TMAH-degrading cells associated with the genus Methanomethylovorans were not intermingled with other microorganisms but rather isolated on the granule's surface as a lone dominant archaeon. KEY POINTS: • A TMAH-degrading methanogenic Methanomethylovorans strain was isolated • This strain was the only known Methanomethylovorans isolate that can degrade TMAH • The highest cell yield of the isolate was obtained at psychrophilic conditions.

Fine, Vascular Network Formation in Patients with Vein of Galen Aneurysmal Malformation

BACKGROUND AND PURPOSE

A vein of Galen aneurysmal malformation is known to present with recruitment of dural feeders and, in our cohort, a fine, vascular network formation. The vessels we have observed differ from dural vascular recruitment in that they produce a hairlike, collateral network of vessels. We reviewed treatment courses of vein of Galen aneurysmal malformation treatments in a series of 36 cases that displayed a fine, vascular network formation.

MATERIALS AND METHODS

We retrospectively analyzed 36 cases of vein of Galen aneurysmal malformation, including tectal/thalamic AVMs, treated at our center from January 2004 to September 2021, and reviewed fine, vascular network formations in the subarachnoid space and subependymal zone alongside the vein of Galen aneurysmal malformation.

RESULTS

Patients at first endovascular treatment ranged from neonates to 157 months (median age, 4.3 months). Patients with preinterventional fine, vascular network formations were significantly older at the initial angiogram than patients with postinterventional fine, vascular network formations (P < .05). On average, for 20 control choroidal/mural vein of Galen aneurysmal malformations whose treatment course had been completed and in which no plexiform network was visualized, a mean of 2.63 (SD, 1.64) treatments were required to achieve a radiographic cure. For the 36 choroidal/mural vein of Galen aneurysmal malformations whose treatment course had been completed and in which a fine, vascular network formation was visualized, a mean of 5.94 (SD, 2.73) treatments were required to achieve a radiographic cure (P < .01).

CONCLUSIONS

Development of a fine, vascular network formation is an acquired and reversible phenomenon that differs from typical dural vessel recruitment, given the hairlike nature of the network and its rapid onset postinterventionally. It typically resolves after completion of treatment, and this resolution correlates with closure of the vein. We recommend that neurointerventionalists avoid delays in treatment wherever possible to reduce the likelihood of a fine, vascular network formation.

Prevalence of Hoarseness and Its Association with Severity of Dysphagia in Patients with Sarcopenic Dysphagia

OBJECTIVES

To investigate the prevalence of hoarseness and its association with the severity of dysphagia in patients with sarcopenic dysphagia.

DESIGN

Cross-sectional study using the Japanese sarcopenic dysphagia database.

SETTING

19 hospitals including 9 acute care hospitals, 8 rehabilitation hospitals, 2 long-term care hospitals, and 1 home visit rehabilitation team.

PARTICIPANTS

287 patients with sarcopenic dysphagia, aged 20 years and older.

MEASUREMENTS

Sarcopenic dysphagia was diagnosed using a reliable and validated diagnostic algorithm for the condition. The presence and characteristics of hoarseness classified as breathy, rough, asthenic, and strained were assessed. The prevalence of hoarseness and the relationship between hoarseness and Food Intake LEVEL Scale (FILS) were examined. Order logistic regression analysis adjusted for age, sex, naso-gastric tube, and handgrip strength was used to examine the relationship between hoarseness and FILS at baseline and at follow-up.

RESULTS

The mean age was 83 ± 10 years. Seventy-four (26%) patients had hoarseness, while 32 (11%), 20 (7%), 22 (8%), and 0 (0%) patients had breathy, rough, asthenic, and strained hoarseness, respectively. Median FILS at the initial evaluation was 7 (interquartile range, 5-8). Hoarseness (β=0.747, 95% confidence intervals= 0.229, 1.265, p=0.005), age, sex, naso-gastric tube, and handgrip strength were associated independently with baseline FILS, while hoarseness (β=0.213, 95% confidence intervals= -0.324, 0.750, p=0.438) was not associated independently with the FILS at follow-up.

CONCLUSIONS

Hoarseness was associated with the severity of dysphagia at baseline, however not a prognostic factor for sarcopenic dysphagia. Resistance training of swallowing and respiratory muscles and voice training as part of rehabilitation nutrition might be useful for treating sarcopenic dysphagia.

Association between Inflammation and Functional Outcome in Patients with Sarcopenic Dysphagia

OBJECTIVES

This study aimed to investigate whether inflammation affects the outcome of swallowing ability to improve treatment for sarcopenic dysphagia.

DESIGN

A retrospective observational cohort study was performed using data from the Japanese sarcopenic dysphagia database.

SETTING

The database was constructed using data from 19 hospitals and one home visiting rehabilitation team.

PARTICIPANTS

Patients with sarcopenic dysphagia with measurements of C-reactive protein (CRP) and serum albumin (Alb) were included.

MEASUREMENTS

Patients were assigned to two groups using CRP, Alb, and the Japanese modified Glasgow Prognostic Score (mGPS). The Food Intake LEVEL Scale (FILS) was measured at the times of admission and follow-up (FILS follow-up) to assess swallowing function.

RESULTS

A total of 197 patients were included. Mean or median values of each parameter were as follows: age: 83.8±8.7, Alb: 3.2 ± 0.6 g/dL, CRP: 8.0 [3.0, 29.0] mg/L, mGPS: 1 [1-2], FILS: 7 [6-8], FILS follow-up: 8 [7-8], and duration of follow-up: 57.0 [27.0, 85.0] days. The FILS score at follow-up was significantly lower in the high CRP group (≥ 5.0 mg/L) than in the low CRP group (< 5.0 mg/L) (p = 0.01). Further, the FILS score at follow-up was significantly lower in the high mGPS group (class; 2) than in the low mGPS group (class; 0 and 1) (p = 0.03). In the multiple linear regression analyses without FILS at baseline, CRP and mGPS were independent risk factors for FILS follow-up. When FILS at baseline was entered, CRP and mGPS were not an independent risk factors for FILS follow-up.

CONCLUSIONS

Inflammation could modify the outcome of the patients with sarcopenic dysphagia. Inflammation may be an important risk factor in evaluating patients with sarcopenic dysphagia.

A Radiologic Grading System for Assessing the Radiographic Outcome of Treatment in Lymphatic and Lymphatic-Venous Malformations of the Head and Neck

BACKGROUND AND PURPOSE

Two-thirds of lymphatic malformations in children are found in the head and neck. Although conventionally managed through surgical resection, percutaneous sclerotherapy has gained popularity. No reproducible grading system has been designed to compare sclerotherapy outcomes on the basis of radiologic findings. We propose an MR imaging-based grading scale to assess the response to sclerotherapy and present an evaluation of its interrater reliability.

MATERIALS AND METHODS

A grading system was developed to stratify treatment outcomes on the basis of interval changes observed on MR imaging. By means of this system, 56 consecutive cases from our institution with formally diagnosed head and neck lymphatic malformations treated by sclerotherapy were retrospectively graded. Each patient underwent pre- and posttreatment MR imaging. Each study was evaluated by 3 experienced neuroradiologists. Interrater reliability was assessed using the Krippendorff α statistic, intraclass coefficient, and 2-way Spearman ρ correlation.

RESULTS

The overall Krippendorff α statistic was 0.93 (95% CI, 0.89-0.95), denoting excellent agreement among raters. Intraclass coefficients with respect to consistency and absolute agreements were both 0.97 (95% CI, 0.96-0.98), illustrating low variability. Every combination of individual rater pairs demonstrated statistically significant (P < .01) linear Spearman ρ correlations, with values ranging from 0.90 to 0.95.

CONCLUSIONS

The proposed radiographic grading scale demonstrates excellent interrater reliability. Adoption of this new scale can standardize reported outcomes following sclerotherapy for head and neck lymphatic malformation and may aid in the investigation of future questions regarding optimal management of these lesions.

Genomic and Metabolomic Analyses of a Piezosensitive Mutant of Saccharomyces cerevisiae and Application for Generation of Piezosensitive Niigata-Sake Yeast Strains

A sparkling-type draft cloudy sake (Japanese rice wine), AWANAMA, was recently developed using high hydrostatic pressure (HHP) treatment as a non-thermal pasteurization method. This prototype sake has a high potential market value, since it retains the fresh taste and flavor similar to draft sake while avoiding over-fermentation. From an economic point of view, a lower pressure level for HHP pasteurization is still required. In this study, we carried out a genome analysis of a pressure-sensitive (piezosensitive) mutant strain, a924E1, which was generated by UV mutagenesis from a laboratory haploid Saccharomyces cerevisiae strain, KA31a. This mutant strain had a deletion of the COX1 gene region in the mitochondrial DNA and had deficient aerobic respiration and mitochondrial functions. A metabolomic analysis revealed restricted flux in the TCA cycle of the strain. The results enabled us to use aerobic respiration deficiency as an indicator for screening a piezosensitive mutant. Thus, we generated piezosensitive mutants from a Niigata-sake yeast strain, S9arg, which produces high levels of ethyl caproate but does not produce urea and is consequently suitable for brewing a high-quality sake. The resultant piezosensitive mutants showed brewing characteristics similar to the S9arg strain. This study provides a screening method for generating a piezosensitive yeast mutant as well as insight on a new way of applying HHP pasteurization.

Racial and Socioeconomic Disparities in the Use and Outcomes of Endovascular Thrombectomy for Acute Ischemic Stroke

BACKGROUND AND PURPOSE

Racial and socioeconomic disparities in the incidence, treatment, and outcomes of acute ischemic stroke exist and have been described. We aimed to characterize disparities in the use of endovascular thrombectomy in a nationally representative analysis.

MATERIALS AND METHODS

Discharge data from the Nationwide Inpatient Sample between 2006 and 2016 were queried using validated International Classification of Disease codes. Patients admitted to US hospitals with acute ischemic stroke were included and stratified on the basis of race, income, and primary payer. Trends in endovascular thrombectomy use, good outcome (discharge to home/acute rehabilitation), and poor outcome (discharge to skilled nursing facility, hospice, in-hospital mortality) were studied using univariate and multivariable analyses.

RESULTS

In this analysis of 1,322,162 patients, endovascular thrombectomy use increased from 53/111,829 (0.05%) to 3054/146,650 (2.08%) between 2006 and 2016, respectively. Less increase was observed in black patients from 4/12,733 (0.03%) to 401/23,836 (1.68%) and those in the lowest income quartile from 10/819 (0.03%) to 819/44,984 (1.49%). Greater increase was observed in the highest income quartile from 18/22,138 (0.08%) to 669/27,991 (2.39%). Black race predicted less endovascular thrombectomy use (OR = 0.79; 95% CI, 0.72-0.86). The highest income group predicted endovascular thrombectomy use (OR = 1.24; 95% CI, 1.13-1.36) as did private insurance (OR = 1.30; 95% CI, 1.23-1.38). High income predicted good outcome (OR = 1.10; 95% CI. 1.06-1.14), as did private insurance (OR = 1.36; 95% CI, 1.31-1.39). Black race predicted poor outcome (OR = 1.33; 95% CI, 1.30-1.36). All results were statistically significant (P < .01).

CONCLUSIONS

Despite a widespread increase in endovascular thrombectomy use, black and low-income patients may be less likely to receive endovascular thrombectomy. Future effort should attempt to better understand the causes of these disparities and develop strategies to ensure equitable access to potentially life-saving treatment.

The Mass of Geniohyoid Muscle Is Associated with Maximum Tongue Pressure and Tongue Area in Patients with Sarcopenic Dysphagia

OBJECTIVES

We investigated the associations about the mass of geniohyoid and tongue muscle and the maximum tongue pressure in patients with sarcopenic dysphagia using ultrasonography.

DESIGN

Cross sectional study.

SETTING

5 hospitals including 3 acute and 2 rehabilitation hospitals and 1 older facility.

PARTICIPANTS

36 inpatients with sarcopenic dysphagia.

MEASUREMENTS

Ultrasonography was performed for geniohyoid muscle and tongue. The area for geniohyoid and tongue muscles in sagittal plane and the mean brightness level (0-255) in the muscle area were calculated. Maximum tongue pressure as strength of swallowing muscle were investigated. Partial correlation coefficient and multiple regression analysis adjusting for age and sex were performed.

RESULTS

The mean age was 81.1 ± 7.9. Men were 23. The mean BMI was 19.0 ± 4.1. The mean maximum tongue pressure was 21.3 ± 9.3 kPa. The mean cross sectional area for geniohyoid muscles was 140 ± 47 mm2. The mean brightness for geniohyoid muscle was 18.6 ± 9.0. The mean cross sectional area for tongue muscles was 1664.1 ± 386.0 mm2. The mean brightness for tongue muscles was 34.1 ± 10.6. There was a significant positive correlation between area of geniohyoid muscle and maximum tongue pressure (r = 0.38, p = 0.04). Geniohyoid muscle area was an explanatory factor for maximum tongue pressure (p = 0.012) and tongue muscle area (p = 0.031) in multivariate analysis.

CONCLUSIONS

Geniohyoid muscle mass was an independent explanatory factor for maximum tongue pressure and tongue muscle mass.

Clinical usefulness of relative apical sparing pattern for predicting functional recovery after transcatheter aortic valve implantation in patients with severe aortic stenosis

Background

Relative apical sparing pattern (RASP) is thought to be associated with prognosis in patients with cardiac amyloidosis or left ventricular hypertrophy (LVH). Although almost all patients with severe aortic stenosis (AS) have LVH, little is known about the effect of transcatheter aortic valve implantation (TAVI) in patients with severe AS exhibiting a RASP.

Purpose

This study aimed to elucidate the effect of TAVI on left ventricular global longitudinal strain (LS; LVGLS) in patients with severe AS exhibiting a RASP.

Methods

Eighty-four patients who underwent transfemoral or subclavian TAVI were evaluated. They were divided into the RASP and non-RASP groups. The average apical LS divided by the sum of the average mid and basal LS values of &gt;1.0 was defined as the RASP. We analyzed the difference between pre- and post-TAVI LVGLS (ΔGLS = post-TAVI LVGLS − pre-TAVI LVGLS).

Results

Of the 84 patients (mean age, 84.5±3.9 years; 24 men), 15 (17.9%) exhibited a RASP. No significant difference in mean pre-TAVI LVGLS was found between the RASP and non-RASP groups (−16.6% ± 3.8% vs. −15.8% ± 3.9%). The ΔGLS in the RASP group was significantly higher than that in the non-RASP group (−0.97% ± 2.5% vs. −2.6% ± 3.0%; P&lt;0.05). Multivariate analysis revealed that relative apical longitudinal strain was an independent predictor of ΔGLS (β = 0.35, p=0.002).

Conclusion

Relative apical longitudinal strain was associated with LVGLS recovery. The effect of TAVI on LVGLS in patients with a RASP is inferior to that in patients without a RASP.

Funding Acknowledgement

Type of funding source: None

Initial Stroke Thrombectomy Experience in New York City during the COVID-19 Pandemic

New York City has become the global epicenter of the coronavirus 2019 (COVID-19) pandemic. Despite a massive shift in health care resources, cerebrovascular disease continues to be a substantial burden. We review the first 10 patients undergoing thrombectomy following a series of governmental and institutional policy changes diverting resources to the care of critically ill patients with COVID-19. Ten patients with emergent large-vessel occlusion underwent thrombectomy between March 23 and April 1, 2020. Five patients tested positive for the COVID-19 virus. Successful reperfusion was achieved in 9 of 10 patients, at a median time of 37 minutes from vascular access. The postprocedural NIHSS score improved by an average of 7.7 points. Of the 5 patients positive for COVID-19, none have experienced a critical respiratory illness. We report the early incidence of COVID-19 positivity in patients with emergent large-vessel occlusion and demonstrate that thrombectomy continues to be an efficacious option, as well as safe for health care providers.

P6005Incidence and clinical characteristics of coronary artery spasm in patients with out-of-hospital cardiac arrest

Background

Substantial cases of out-of-hospital cardiac arrest (OHCA) due to acute coronary syndrome have been recognized thus far, but there have been few reports about the aetiology of patients with OHCA without the organic heart disease. Especially, coronary artery spasm would be one of the causes of OHCA.

Purpose

This study aimed to investigate causes of OHCA without the organic heart disease and to investigate the characteristics and angiographic findings of OHCA patients with vasospastic angina (VSA).

Methods

Between January 2010 and April 2018, 920 patients with OHCA caused by probable or definite cardiovascular disease were transferred to our hospital. Return of spontaneous contraction was successfully achieved in 151 patients, among whom diagnosis was made in 130 patients. First, we analysed the causes of OHCA in these patients. Second, we compared clinical and angiographic characteristics between the VSA group with OHCA (OHCA-VSA) and the VSA group without OHCA (stable VSA; n=72) from our database.

Results

Among the 130 patients, 95 (73%) had the organic heart disease; 72, acute coronary syndrome; 19, myocardial disease; 2, valvular heart disease; and 1, congenital heart disease. There were 35 patients (27%) without the organic heart disease. Nineteen patients had primary (i.e., Brugada syndrome, QT prolongation) or secondary arrhythmia (i.e. drug adverse effect). Electrocardiogram, coronary angiogram, and LV structure and function were normal in 35 patients. However, there were 16 patients (11%) with VSA defined by Japanese guideline. The OHCA-VSA group was significantly younger (50±14) than the stable VSA group (64±11, P=0.003). The incidence of diffuse-type spasm in the OHCA-VSA group (100%) was significantly higher than that in the stable VSA group (100% vs. 69%, P<0.05). In addition, the incidence of triple-vessel coronary spasm in the OHCA-VSA group was significantly higher than that in the stable VSA group (86% vs. 25%, P=0.003).

Conclusion

OHCA patients without the organic heart disease had considerable cases of VSA, in addition to primary or secondary arrhythmia. Furthermore, the severity of spasm in the OHCA-VSA group was more serious and extensive than in comparison with the stable VSA group.

Comparative analysis on inactivation kinetics of between piezotolerant and piezosensitive mutant strains of Saccharomyces cerevisiae under combinations of high hydrostatic pressure and temperature

We previously obtained a pressure-tolerant (piezotolerant) and a pressure sensitive (piezosensitive) mutant strain, under ambient temperature, from Saccharomyces cerevisiae strain KA31a. The inactivation kinetics of these mutants were analyzed at 150 to 250MPa with 4 to 40°C. By a multiple regression analysis, the pressure and temperature dependency of the inactivation rate constants k values of both mutants, as well as the parent strain KA31a, were well approximated with high correlation coefficients (0.92 to 0.95). For both mutants, as well as strain KA31a, the lowest k value was shown at a low pressure levels with around ambient temperature. The k value approximately increased with increase in pressure level, and with increase and decrease in temperature. The piezosensitive mutant strain a924E1 showed piezosensitivity at all pressure and temperature levels, compared with the parent strain KA31a. In contrast, the piezotolerant mutant strain a2568D8 showed piezotolerance at 4 to 20°C, but did not show significant piezotolerance at 40°C. These results of the variable influence of temperature on pressure inactivation of these strains would be important for better understanding of piezosensitive and piezotolerant mechanisms, as well as the pressure inactivation mechanism of S. cerevisiae.

Effects of High Hydrostatic Pressure on Water Absorption of Adzuki Beans

The effect of high hydrostatic pressure (HHP) treatment on dried soybean, adzuki bean, and kintoki kidney bean, which are low-moisture-content cellular biological materials, was investigated from the viewpoint of water absorption. The samples were vacuum-packed with distilled water and pressurized at 200 MPa and 25 °C for 10 min. After the HHP treatment, time courses of the moisture contents of the samples were measured, and the dimensionless moisture contents were estimated. Water absorption in the case of soybean could be fitted well by a simple water diffusion model. High pressures were found to have negligible effects on water absorption into the cotyledon of soybean and kintoki kidney bean. A non-linear least square method based on the Weibull equation was applied for the adzuki beans, and the effective water diffusion coefficient was found to increase significantly from 8.6 × 10^-13 to 6.7 × 10^-10 m²/s after HHP treatment. Approximately 30% of the testa of the adzuki bean was damaged upon HHP treatment, which was comparable to the surface area of the testa in the partially peeled adzuki bean sample. Thus, HHP was confirmed to promote mass transfer to the cotyledon of legumes with a tight testa.

Barosensitivity in Saccharomyces cerevisiae is Closely Associated with a Deletion of the COX1 Gene

High hydrostatic pressure causes physical stress to microorganisms; therefore, this technology may be applied to food pasteurization without introducing the unfavorable effects of thermal denaturation. However, its application is limited to high-value foods because the treatment requires a robust steel vessel and expensive pressurization equipment. To reduce these costs, we studied the pasteurization of Saccharomyces cerevisiae using relatively moderate high-pressure levels. A mutant strain isolated by ultraviolet mutagenesis showed significant loss of viability under high-pressure conditions. Gene expression analysis of the mutant strain revealed that it incurred a deletion of the COX1 gene. Our results suggest that the pressure-sensitivity can readily be introduced into industrial/food microorganisms by complementing a COX1 deleted mitochondria.

Use of Pressure Activation in Food Quality Improvement

Beside intensive studies on inactivation microorganisms by high hydrostatic pressure (HP) for food storage, pressure effects on property of food materials have also been studied based on knowledge in pressure effect on biomolecules. Pressure effects on biological membranes and mass transfer in cellular biological materials and on enzyme activity would give an idea that HP treatment can introduce two types of activations into food materials: improved mass transfer and enzyme activity. Studies focusing on these pressure activations on food materials were then reviewed. Rice flour with an exclusively fine mean particle size and small starch damage was obtained due to improved water absorption properties and/or enzyme activity by HP. HP treatment increased of free amino acids and γ-aminobutyric acid (GABA) in rice and soybeans due to improved proteolysis and amino acid metabolism. Improvement of antioxidant activity and alteration of polyphenolic-compounds composition in food materials were also demonstrated by HP treatment. The HP-induced activations on food materials could contribute towards processing technologies for food quality improvement.

In VitroEvaluation of Physiological Activity of Vinegar Produced from Barley-, Sweet Potato-, and Rice-shochuPost-distillation Slurry

Vinegar was produced from barley-, sweet potato-, and rice-shochu post-distillation slurry using jar fermentor within 19 hrs. All the vinegars showed radical-scavenging activity, angiotensin I converting enzyme (ACE) inhibition and advanced glycation endproducts (AGE) inhibition in vitro. The radical-scavenging activity of the vinegar produced from sweet potato-shochu post-distillation slurry was higher than that of other two kinds of vinegar on the organic matter basis. The ACE inhibitory activities of all the vinegars were higher than that of each post-distillation slurry. The main components that showed ACE inhibitory activity would be peptides, and their content increased during acetic acid fermentation. Regarding AGE inhibition, only rice-shochu post-distillation slurry did not show such activity, but the other two post-distillation slurries and all the vinegars showed clear inhibitory activity. The activity appeared to depend on the concentration of amino groups except for sweet potato-shochu post-distillation slurry and the vinegar produced from it.

Polyphenol-Retaining Decaffeinated Cocoa Powder Obtained by Supercritical Carbon Dioxide Extraction and Its Antioxidant Activity

Cocoa beans contain many functional ingredients such as theobromine and polyphenols, but also contain a relatively high amount of caffeine, which can negatively impact human health. It is therefore desirable to reduce caffeine levels in cocoa powder used to make chocolate or cocoa beverages while retaining functional ingredients. We have established conditions for supercritical carbon dioxide (SCCO₂) extraction that remove 80.1% of the caffeine from cocoa powder while retaining theobromine (94.1%) and polyphenols (84.7%). The antioxidant activity of the decaffeinated cocoa powder (DCP) made with this optimized SCCO₂ extraction method was 85.3% that of non-processed cocoa powder. The total procyanidin and total polyphenol concentrations of the DCPs resulting from various SCCO₂ extractions showed a significant positive correlation with oxygen radical absorbance capacity (ORAC). The correlation coefficient between total polyphenols and ORAC was higher than that between total procyanidins and ORAC; thus, the concentration of total polyphenols might be a greater factor in the antioxidant activity of DCP. These results indicate that we could remove large quantities of caffeine from conventional high-cocoa products while retaining the functional benefits of high polyphenol content. This SCCO₂ extraction method is expected to be applicable high-cocoa products, such as dark chocolate.

Diversities and similarities in pH dependency among bacterial NhaB-like Na+/H+ antiporters

NhaB-like antiporters were the second described class of Na(+)/H(+) antiporters, identified in bacteria more than 20 years ago. While nhaB-like gene sequences have been found in a number of bacterial genomes, only a few of the NhaB-like antiporters have been functionally characterized to date. Although earlier studies have identified a few pH-sensitive and -insensitive NhaB-like antiporters, the mechanisms that determine their pH responses still remain elusive. In this study, we sought to investigate the diversities and similarities among bacterial NhaB-like antiporters, with particular emphasis on their pH responsiveness. Our phylogenetic analysis of NhaB-like antiporters, combined with pH profile analyses of activities for representative members of several phylogenetic groups, demonstrated that NhaB-like antiporters could be classified into three distinct types according to the degree of their pH dependencies. Interestingly, pH-insensitive NhaB-like antiporters were only found in a limited proportion of enterobacterial species, which constitute a subcluster that appears to have diverged relatively recently among enterobacterial NhaB-like antiporters. Furthermore, kinetic property analyses of NhaB-like antiporters at different pH values revealed that the degree of pH sensitivity of antiport activities was strongly correlated with the magnitude of pH-dependent change in apparent Km values, suggesting that the dramatic pH sensitivities observed for several NhaB-like antiporters might be mainly due to the significant increases of apparent Km at lower pH. These results strongly suggested the possibility that the loss of pH sensitivity of NhaB-like antiporters had occurred relatively recently, probably via accumulation of the mutations that impair pH-dependent change of Km in the course of molecular evolution.

Epidural anesthesia during upper abdominal surgery provides better postoperative analgesia

Since repeated noxious stimuli may sensitize neuropathic pain receptors of the spinal cord, we tested the hypothesis that the appropriate blockade of surgical stimuli with epidural anesthesia during upper abdominal surgery would be beneficial for postoperative analgesia. Thirty-six adult patients undergoing either elective gastrectomy or open cholecystectomy were randomly allocated to receive either inhalational general anesthesia alone (group G) or epidural anesthesia along with light general anesthesia (group E) throughout the surgery. Postoperative pain management consisted of patient-controlled analgesia (PCA) with bupivacaine accompanied by the continuous infusion of buprenorphine. To assess postoperative pain, a visual analogue scale (VAS) was employed at 2, 24, and 48 h postoperatively. While there was no significant difference in the bupivacaine dose, more patients undergoing gastrectomy in group G required supplemental analgesics than those in group E, and the VAS scores in group E demonstrated significantly better postoperative analgesia compared to group G after both types of surgery. Thus, an appropriate epidural blockade during upper abdominal surgery likely provides better postoperative pain relief.

Enzymatic production of γ-aminobutyric acid in soybeans using high hydrostatic pressure and precursor feeding

The effects were investigated of the glutamic acid (Glu) substrate concentration on the generation and kinetics of γ-aminobutyric acid (GABA) in soybeans treated under high hydrostatic pressure (HHP; 200 MPa for 10 min at 25 °C). The conversion of Glu to GABA decreased with increasing initial Glu concentration in the soybeans. The crude glutamate decarboxylase (GAD) obtained from the HHP-treated soybeans showed substrate inhibition. The GABA production rate in the HHP-treated soybeans fitted the following substrate inhibition kinetic equation: v0=(VmaxS0)/(Km+S0+(S0)2/Ki). The Km value for the HHP-treated soybeans was significantly higher than that of the untreated soybeans. The Km values in this study show the affinity between Glu and GAD, and indicate that the HHP-treated soybeans had lower affinity between Glu and GAD than the untreated soybeans. GAD extracted from the HHP-treated soybeans showed a similar value to that in the HHP-treated soybeans. The intact biochemical system was so damaged in the HHP-treated soybeans that it showed substrate inhibition kinetics similar to that of the extracted GAD. The combination of HHP and precursor feeding proved to be a novel tool that can be used to increase the concentration of a target component.

High-throughput method for a kinetics analysis of the high-pressure inactivation of microorganisms using microplates

Using microplates as pressure and cultivation vessels, a high-throughput method was developed for analyzing the high-pressure inactivation kinetics of microorganisms. The loss of viability from a high-pressure treatment, measured based on the growth delay during microplate cultivation, showed reproducibility with the conventional agar plate method and was applicable for the kinetics analysis.

Detection of active, potentially acetate-oxidizing syntrophs in an anaerobic digester by flux measurement and formyltetrahydrofolate synthetase (FTHFS) expression profiling

Syntrophic oxidation of acetate, so-called reversed reductive acetogenesis, is one of the most important degradation steps in anaerobic digesters. However, little is known about the genetic diversity of the micro-organisms involved. Here we investigated the activity and composition of potentially acetate-oxidizing syntrophs using a combinatorial approach of flux measurement and transcriptional profiling of the formyltetrahydrofolate synthetase (FTHFS) gene, an ecological biomarker for reductive acetogenesis. During the operation of a thermophilic anaerobic digester, volatile fatty acids were mostly depleted, suggesting a high turnover rate for dissolved H(2), and hydrogenotrophic methanogens were the dominant archaeal members. Batch cultivation of the digester microbiota with (13)C-labelled acetate indicated that syntrophic oxidation accounted for 13.1-21.3 % of methane production from acetate. FTHFS genes were transcribed in the absence of carbon monoxide, methoxylated compounds and inorganic electron acceptors other than CO(2), which is implicated in the activity of reversed reductive acetogenesis; however, expression itself does not distinguish whether biosynthesis or biodegradation is functioning. The mRNA- and DNA-based terminal RFLP and clone library analyses indicated that, out of nine FTHFS phylotypes detected, the FTHFS genes from the novel phylotypes I-IV in addition to the known syntroph Thermacetogenium phaeum (i.e. phylotype V) were specifically expressed. These transcripts arose from phylogenetically presumed homoacetogens. The results of this study demonstrate that hitherto unidentified phylotypes of homoacetogens are responsible for syntrophic acetate oxidation in an anaerobic digester.

True Atomic Resolution Imaging on Semiconductor Surfaces with Noncontact Atomic Force Microscopy

The constant vibration mode and the constant excitation mode in noncontact atomic force microscopy were compared to investigate the force interaction between tip and surface. As a result, we found that the constant excitation mode is much more gentle than the constant vibration mode. We also succeeded in atomic resolution imaging on InP(110) surface not only in the noncontact region but in the contact region for the first time. Furthermore, we found the discontinuity of the force gradient curve on reactive Si(111)7×7 reconstructed surface. We proposed a model to explain the discontinuity with the crossover between the physical and chemical bonding interaction.

Generation of free amino acids and gamma-aminobutyric acid in water-soaked soybean by high-hydrostatic pressure processing

The effects of high-hydrostatic pressure processing (HPP) on soybean cotyledon as a cellular biological material were investigated from the viewpoints of the cell structure and enzyme reaction system. Damage to cell structure was evaluated by measuring dielectric properties using the Cole-Cole arc, the radius of which decreased as pressure level increased. Results suggested that cell structure was damaged by HPP. The distribution of free amino acids was measured after HPP (200 MPa) of soybean soaked in water or sodium glutamate (Glu) solution. HPP resulted in high accumulation of free amino acids in water-soaked soybean, due to proteolysis. HPP of soybean in Glu solution caused higher accumulation of gamma-aminobutyric acid, suggesting that both proteolysis and specific Glu metabolism were accelerated by HPP. We concluded that HPP partially degraded cell structure and accelerated biochemical reactions by allowing enzyme activities to remain. These events can be considered "high-pressure induced transformation" of soybean.

A culture-dependent bacterial community structure analysis based on liquid cultivation and its application to a marine environment

A method for analyzing culture-dependent bacterial community structure by liquid cultivation was established using 96-well microplates. Using 96-well microplates, this method can easily provide accurate enumeration of viable microorganisms and simultaneous separation of bacteria, which allowed us to analyze the bacterial community. Bacteria in diluted surface seawater were separated using 96-well microplates and cultivated with 1/5 ZoBell 2216E liquid medium. The 98 cultures obtained were subsequently applied to phylogenetic analysis based on 16S rRNA gene sequences. The bacterial diversity, evaluated by the Shannon-Weaver index, was relatively small but comparable to previously reported bacterial communities of several environments. The most abundant group was the family Rhodobacteraceae, which has been frequently detected in marine environments. Most bacteria were phylogenetically related to bacteria or uncultured clones detected in marine environments, but distant from published species. The analysis of bacterial community structure by liquid cultivation would be useful as an alternative culture-dependent approach.

Antioxidant activity of vinegar produced from distilled residues of the Japanese liquor shochu

Rice shochu distilled residue (RSDR) is a byproduct of rice shochu production. RSDR was converted into vinegar by acetate fermentation. In our present study, two major antioxidant compounds, tyrosol and ferulic acid, were identified from the RSDR-derived vinegar. Furthermore, we investigated the antioxidant activity of freeze-dried RSDR-derived vinegar, which was Acetobactor aceti fermentation powder (AFP), in vitro and in vivo. AFP at 0.25 mg/mL or higher concentrations showed an inhibitory effect against lipid peroxidation and cellular GSH depletion in HepG2 cells induced by H(2)O(2) (P < 0.05). We thus considered the potential of AFP in protecting cells against damage induced by H(2)O(2). Its antioxidant activity was evaluated in vivo using carbon tetrachloride (CCl(4))-induced acute liver injury mouse models. Five consecutive days of oral preadministration of AFP dissolved in PBS at 200, 400, and 800 mg/kg body weight significantly suppressed lipid peroxidation in the liver induced by CCl(4) (P < 0.01). Consequently, treatment with AFP at 200 mg/kg body weight or higher doses suppressed the elevation of alanine aminotransferase and aspartate aminotransferase levels in serum (P < 0.05). These findings suggest that RSDR-derived vinegar can be developed as a health food with an antioxidant effect for the prevention of oxidative injury and cancer.