Deterioration of cardiogenic shock after acute myocardial infarction defined by the society for cardiovascular angiography and intervention cardiogenic shock classification scheme

Background

Cardiogenic shock (CS) in patients with AMI presents worse cardiovascular outcomes, which suggests the need for better risk stratification and management. The Society for Cardiovascular Angiography and Intervention (SCAI) has recently proposed CS classification scheme, which stratifies CS into 5 groups according to hypotension and hypoperfusion. While stage A and B exhibits CS without hypotension and/or hypoperfusion, their clinical condition could rapidly deteriorate into stage C-E. However, clinical characteristics and in-hospital outcomes of CS exhibiting its deterioration remains uncertain.

Purpose

To characterize AMI patients who deteriorated their CS status from stage A and B into stage C-E.

Methods

This single-center observational study included 326 consecutive AMI patients receiving primary PCI who presented CS stage A and B on arrival (2019.09.01–2021.09.30). Deterioration of CS (D-CS) was defined as the progression from stage A and B on arrival to stage C-E after primary PCI. Clinical characteristics and outcomes were compared in those with and without D-CS.

Results

D-CS was identified in 16.0% of entire subjects (=52/326). Of these, 94.2 and 5.8% of them exhibited stage C and E, respectively (Figure). Patients with D-CS more likely presented STEMI (84.6 vs. 67.9%, p=0.01) with a lower systolic BP (sBP) level (130±31 vs. 148±26mmHg, p<0.001) and a reduced LVEF (43±13 vs. 51±9%, p<0.001), whereas there was no significant difference in lactate level (1.5±0.4 vs. 1.2±0.3 mmol/L, p=0.22). Pre-TIMI flow grade 0–1 (69.2 vs. 47.8%, p=0.006), left main trunk stenosis (9.6 vs. 1.5%, p=0.007) and chronic total occlusion (21.2 vs. 8.4%, p=0.01) were more frequently observed in those with D-CS. Despite achieving a shorter onset-to-reperfusion time (199 vs. 276 minutes, p=0.002), D-CS was associated with in-hospital all-cause mortality after adjusting clinical characteristics (HR=33.6, 95% CI: 2.2–502.0, p=0.01). Furthermore, mechanical circulatory support (MCS) (30.8 vs. 0%, p<0.001) was more frequently required in patients with D-CS (IABP: 28.8 vs. 0%, p<0.001, ECMO: 11.5 vs. 0%, p<0.001, Impella: 3.8 vs. 0%, p=0.02). Further analysis identified sBP (HR=0.98, 95% CI: 0.97–1.00, p=0.008), LVEF (HR=0.94, 95% CI: 0.90–0.97, p<0.001) and pre-TIMI flow grade 0–1 (HR=0.41, 95% CI: 0.19–0.86, p=0.01) as independent contributors to D-CS. ROC analysis demonstrated sBP <135 mmHg (AUC=0.65) and LVEF <50% (AUC=0.69) as best cut-off values to predict D-CS. Of note, a risk of D-CS increased in association with the number of these three factors (p<0.001), and 44.0% of those with all of these factors presented D-CS (Figure).

Conclusion

16.0% of AMI without any hypotension/hypoperfusion on arrival exhibited deterioration of CS status on SCAI classification. The combination of sBP, LVEF and pre-TIMI flow grade could help to identify AMI subjects with a risk of D-CS, who may benefit from early adoption of intensified management including MCS prior to PCI.

Funding Acknowledgement

Type of funding sources: None.

Substantially elevated thromboembolic and bleeding risks in patients with AMI following acute/subacute stroke events

Introduction

AMI infrequently but concomitantly occurs after stroke events. Current guideline recommends primary PCI with DAPT in the setting of AMI. However, this approach is not necessarily applicable in AMI subjects following acute/subacute stroke events due to its bleeding risk. Clinical management and outcomes of these AMI subjects following remains uncertain.

Purpose

To characterize management and clinical outcomes in patients with AMI following acute/subacute stroke events (=post-stroke AMI).

Methods

The current study retrospectively analyzed 2041 AMI patients hospitalized at our institute from 2007 to 2018. Post-stroke AMI was defined as its occurrence within 14 days after ischemic/hemorrhagic stroke. The use of reperfusion and anti-thrombotic therapies, and the occurrence of major adverse cardiovascular events (=CV death, non-fatal MI and non-fatal stroke) and major bleeding events (BARC type 3 or 5) were compared in post-stroke and non-post-stroke AMI patients.

Results

Post-stroke AMI was identified in 1.1% of entire subjects (=23/2041). Of these, 65% of them (=15/23) had AMI within 3 days from the onset of stoke event. Over 60% of them was due to cardioembolic stroke, followed by hemorrhagic (9%), atherothrombotic ones (8%) and other causes (22%). Post-stroke AMI patients were more likely to exhibit Af (p=0.02) and a history of hemodialysis (p=0.009), and have a lower BMI (p=0.04) and hemoglobin level (p=0.02). They were less likely to receive emergent coronary angiography, and primary PCI was conducted in only 65% of post-stroke AMI patients (Table). Furthermore, they more frequently received thrombectomy (p=0.04) alone rather than stent implantation (p=0.002) (Table). With regard to anti-thrombotic therapy, the proportion of DAPT use was significantly lower in post-stroke AMI subjects (52 vs. 89%, p=0.0001), and 17% of them did not receive any anti-thrombotic agents. Of note, only 48% (p=0.04) and 43% (p=0.0001) of post-stroke AMI patients were treated with other established medical therapies including β-blocker and statin, respectively. During the observational period (median = 2.9 years), post-stroke AMI was associated with a greater likelihood experiencing major adverse cardiovascular events (log-rank p<0.001, Figure), CV death (log-rank p<0.0001) and stroke events (log-rank p<0.0001). Furthermore, the frequency of their major bleeding events was substantially elevated (log-rank p<0.001, Figure).

Conclusions

In our real-world data, the adoption of guideline-recommended reperfusion and anti-thrombotic therapies were considerably low in AMI subjects following acute/subacute stroke events. Given their elevated risk of cardiovascular and bleeding events, it is required to establish better therapeutic management for mitigating their thrombotic/bleeding risks.

Funding Acknowledgement

Type of funding sources: None. Table 1Figure 1

Effects of Imprinting and Water Activity on Transesterification and Thermostability with Lipases in Ionic Liquid

The effect of bio-imprinting and water activity on catalytic activities and the thermostability of lipases was investigated for transesterification using vinyl acetate and benzyl alcohol as substrates in ionic liquid, [Cnmim][PF6] (n=4,6,8), and benzene. The catalytic activities were enhanced by imprinting in benzene and [C4mim][PF6], and the relations between the transesterification activities and the water activity in both solvents were approximately bell shaped. The reactivity of the transesterification in benzene was higher than that in [C4<br /> mim][PF6]. The effects of water activity and imprinting on the kinetic parameters in [C4mim][PF6] were examined. Without controlling the water content, the values of Km,VA and Km,BA (Michaelis constants of vinyl acetate and benzyl alcohol, respectively) decreased, and the values of Vm (maximum rate) increased by imprinting. On the other hand, by controlling the water content in the organic media, the values of Vm, Km,VA, and Km,BA increased by imprinting. The activities of lipase in ionic liquid are more strongly affected by water activity and imprinting than those in benzene. We observed effects of water activity on thermostability but none from imprinting.

Assessment of the 2015 cardiopulmonary resuscitation guidelines for patients with out-of-hospital cardiac arrest: results from the All-Japan Utstein registry

Background

The 2015 cardiopulmonary resuscitation (CPR) guidelines have stressed that high-quality CPR improves survival from cardiac arrest (CA). In particular, the guidelines recommended that it is reasonable for rescuers to perform chest compressions at a rate of 100 to 120/min in adult CA patients. However, it is unknown whether the 2015 guidelines contributed to favorable neurological outcome in adult CA patients. The present study aimed to clarify the effects of the 2015 guidelines in adult CA patients, using the data of the All-Japan Utstein Registry, a prospective, nationwide, population-based registry of out-of-hospital CA (OHCA).

Methods

From the data of this registry between 2011 and 2016, we included adult witnessed OHCA patients due to cardiac etiology, who had non-shockable rhythm as an initial rhythm. We excluded patients who received prehospital care in 2015 because it was difficult to distinguish prehospital care based on either 2010 CPR guidelines or 2015 CPR guidelines. We also excluded patients who received bystander CPR by citizens because we cannot assess the quality of bystander CPR in this registry. Study patients were divided into five groups based on different years (figure). The endpoint was the favorable neurological outcome at 30 days after OHCA. Potential confounding factors based on biological plausibility and previous studies were included in the multivariable logistic regression analysis. These variables included the age, sex (male, female), advanced airway or not, the administration of adrenaline or not, the administration of saline or not, instructed by dispatcher or not, and time interval from call EMS to scene.

Results

The figure showed favorable neurological outcomes at 30 days. In the multivariate analysis, the adjusted odds ratio for 30-day favorable neurological outcome in OHCA patients in 2016 as compared to in 2011 was 1.32 (95% CI: 1.04–1.68, p=0.022). On the other hands, there were no significant differences from 2011 to 2014.

Conclusion

In the OHCA patients with non-shockable rhythm, the 2015 guidelines were superior to the 2010 guidelines, in terms of neurological benefits.

Figure 1

Funding Acknowledgement

Type of funding source: None

0426 Time Restricted Feeding Consolidates Sleep in the BACHD Mouse Model of Huntington’s Disease

Introduction

Disturbances in the daily sleep-wake cycle are common in individuals with neurodegenerative disorders. Huntington’s disease (HD) is a genetic neurodegenerative disorder in which patients exhibit a variety of impairments that include, poor motor function, disrupted circadian rhythms, and sleep abnormalities such as difficulty initiating sleep at bedtime and more frequent nighttime arousals. In the BACHD mouse model time restricted feeding (TRF) has been successful at improving motor functions and circadian rhythms. The BACHD mouse model has a bacterial artificial chromosome that expresses the full-length human mutant huntingtin gene.

Methods

In order to determine the effects of TRF on sleep-wake architecture, EEG/EMG polysomnographic records were examined in mice between 3-4 months old bearing the BAC knock-in of a human genetic mutation of HD and WT litter mates, first during ad libitum (ad lib) feeding then during an 18 hour fasting protocol. TRF protocol consisted of 6 hours of food access limited between ZT15-ZT21 and 18 hours of fasting.

Results

A two-way ANOVA revealed that TRF significantly decreased the amount of total sleep (p=0.04) and NREM sleep (p=0.04) in the dark phase in both WT and BACHD mice. TRF did not significantly affect sleep in the light phase, however trends suggest that BACHD mice have more sleep in the light phase under TRF than ad lib.

Conclusion

This data suggests that TRF improves sleep by consolidating sleep to the light phase and wake to the dark phase. In conclusion, TRF may be a promising tool that can improve the negative effects of neurodegenerative diseases on sleep-wake processes.

Support

These experiments were supported by R01-NS078410 and UCLA start-up funds.

P1561An elevated risk of heart failure and stroke events in octogenarian Japanese patients with acute myocardial infarction who received percutaneous coronary intervention

Background

The proportion of the octogenarian population is expanding especially in Eastern society. Due to the clustering of risk factors, acute myocardial infarction (AMI) represents a major cardiovascular complication in octogenarian subjects. This suggests the need to further optimize their therapeutic management to prevent future cardiac events after AMI. However, analysis of clinical characteristics and cardiovascular outcomes in octogenarian subjects with AMI who received the current established medical therapies is limited.

Purpose

To investigate clinical features and prognosis in octogenarian AMI subjects treated with percutaneous coronary intervention (PCI).

Methods

We analyzed 1547 AMI subjects underwent PCI between 2007 and 2017. Baseline characteristics and the occurrence of composite major adverse cardiovascular events (cardiac death, non-fatal MI, revascularization, heart failure and stroke) were compared in octogenarian and non-octogenarian subjects.

Results

22.0% (340/1547) of study subjects was octogenarian. They were more likely to have chronic kidney disease (CKD) and a lower level of LDL-C on admission (Table). Moreover, a higher prevalence of severer Killip class and LVEF <30% were observed in octogenarians (Table). However, they were not optimally treated with the established medical therapies at discharge (Table). During the observational period (median=3.1 years), the composite of cardiovascular events more frequently occurred in octogenarian subjects. Of note, they exhibited a 2.15-fold and 3.01-fold increased risk for heart failure and stroke events, respectively (Figure).

Table 1 Non-Octogenarian (n=1207) Octogenarian (n=340) P-value CKD* (%) 33.8 63.2 <0.0001 LVEF <30% (%) 5.7 10.3 0.02 Killip class 1.33±0.03 1.55±0.05 <0.0001 LDL-C (mmol/L) 3.20±0.03 2.80±0.05 <0.0001 Statin (%) 86.3 78.2 0.0006 Beta-blocker (%) 74.0 65.8 0.005 ACE-I/ARB (%) 87.3 76.6 <0.0001 DAPT (%) 86.0 88.6 0.42 *CKD is defined as estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2.

Figure 1

Conclusions

Octogenarian subjects with AMI were high-risk group associated with heart failure and stroke events. Their distinct clinical backgrounds may affect the adoption of optimal medical therapies, potentially resulting in worse cardiovascular outcomes. Further intensified management should be applied to octogenarian subjects with AMI.

P2666Association of out-of-hospital cardiac arrest occurrence time and the survival in all-Japan utstein registry: difference between international resuscitation guidelines 2005 and 2010

Background/Introduction

Previous studies have shown that out-of-hospital cardiac arrest (OHCA) occurring at night have poor outcomes compared with OHCA occurring during daytime. On the other hand, nationwide OHCA outcomes have gradually improved in Japan.

Purpose

We sought to examine whether one-month survival of OHCA differed between daytime and nighttime occurrences, and they differed between the periods of International Resuscitation Guidelines 2005 and 2010.

Methods

Using the All-Japan Utstein Registry between 2005 and 2015, adult OHCA patients whose collapse was witnessed by a bystander and the call-to-hospital admission interval was shorter than 120 min were included in this study. OHCA patients were divided by period of the International Resuscitation Guideline 2005 and 2010. Guideline 2005 included years from 2006 to 2010, while Guideline 2010 included years from 2011 to 2015. The primary outcome was one-month survival with favorable neurological outcome, defined as Cerebral Performance Category scale of 1 or 2. Daytime, evening, and night were defined as 0700 to 1459 h, 1500 to 2259 h, and 2300 to 0659 h, respectively.

Results

Among 479,046 cases, 20.3% revealed OHCA occurring at night. OHCA patients occurring at night had lower rate of bystander cardiopulmonary resuscitation (CPR) and automated external defibrillator use than those occurring at both daytime and evening. In addition, of those who received bystander CPR, higher rate of patients received CPR by family members. OHCA patients occurring at night in both guideline periods had significantly worse one-month survival than those occurring during daytime (reference) (adjusted odds ratio, 0.69, 0.64; 95% confidence interval 0.65–0.72, 0.61–0.67; P<0.001, P<0.001, Guideline 2005 and 2010 respectively). OHCA patients occurring during daytime in Guideline 2010 had better one-month survival than those in Guideline 2005 (adjusted odds ratio, 1.29; 95% confidence interval 1.24–1.34; P<0.001).

Conclusions

One-month survival with favorable neurological outcome in OHCA patients occurring at night remains to be significantly worse than those occurring during daytime, even improved by the periods during daytime. CPR training for the family members should be more expanded and strengthened against the night time imperfection.

P1701Sex-related difference in receiving bystander cardiopulmonary resuscitation and clinical outcome among out-of-hospital cardiac arrest patients

Background

Early studies from US and Europe have reported that female out-of-hospital cardiac arrest (OHCA) patients were less likely to receive bystander cardiopulmonary resuscitation (CPR). However, little is known about sex-related difference in receiving CPR and clinical outcome among adult OHCA patients in Japan.

Methods

This study was a nation-wide, population-based observational study of OHCA in Japan from 2011 to 2015. We included all adult cardiogenic OHCA patients. We excluded patients witnessed by emergency medical services (EMS) from the present analysis. To account for the age-related difference, we stratified by age category: 18–39, 40–64, 65–79, and ≥80. To examine the association between patient sex and neurological outcome at 30-day, we fitted multivariable logistic regression model with adjustment for age, bystander CPR status, first document rhythm, dispatcher instruction and EMS response time.

Results

There were 339,317 adult cardiogenic, not EMS-witnessed OHCA patients (median age, 80; female, 43.5%) in Japan from 2011 to 2015. Overall, 171,122 (50.4%) received CPR by citizen, 34,283 (10.1%) had initial shockable rhythm, and 11,421 (3.4%) had favorable neurological status at 30-day. Female patients were more likely to receive bystander CPR (vs. male; 53.8% vs. 47.8%), and were less likely to have initial shockable rhythm (5.2% vs. 13.9%) and favorable neurological status at 30-day (1.8% vs. 4.6%) (all; p<0.001). With stratification by age category, elderly female patients (aged ≥65) were more likely to received bystander CPR (P<0.001), whereas male patients were more likely to received bystander CPR among patients aged <40. Multivariable logistic regression analysis showed that female patients had a lower rate of favorable neurological status at 30-day, compared to male patients in all age categories (all; P<0.05).

Sex difference in bystander CPR Overall Male (n=191,672) Female (n=147,645) p-value All (n=339,317) 50.4% 47.8% 53.8% <0.001 Aged 18–39 (n=6,216) 56.0% 56.9% 53.5% 0.02 Aged 40–64 (n=50,320) 48.5% 48.5% 48.3% 0.69 Aged 65–80 (n=105,141) 46.5% 45.5% 48.3% <0.001 Aged ≥80 (n=177,640) 53.2% 49.0% 56.7% <0.001

OR for neurological outcome at 30-day

Conclusion

Unlike the situation in Europe and US, female OHCA patients, especially elderly female, were more likely to receive bystander CPR in Japan. However, female patients had worse clinical outcome after OHCA. Further investigations including in-hospital treatment are needed to clarify the sex-difference in clinical outcome after OHCA.

Acknowledgement/Funding

None

The Effect of Telephone Advice on Cardiopulmonary Resuscitation (CPR) on the Rate of Bystander CPR in Out-of-Hospital Cardiopulmonary Arrest in a Typical Urban Area

Introduction

The frequency of telephone advice for cardiopulmonary resuscitation (T-CPR) and its effect are unclear. We have few data concerning how many persons who are willing to perform CPR under the setting of the T-CPR system. Most of these data were from action reports in the pre-hospital EMS records. Methods: This study was a population-based observational case series of out-of-hospital cardiopulmonary arrest (OHCPA). The primary outcome was the acceptability of a bystander to perform CPR according to T-CPR. In our emergency department, one medical doctor interviewed the bystanders regarding T-CPR and CPR; this doctor was devoted to obtaining information from the patients.

Results

Of the 803 patients in, T-CPR advice was provided in 47% and CPR was actually performed in 47% independent of T-CPR guidance. Of the 373 cases in which lay persons received T-CPR, 95% provided CPR. Dispatchers could more easily provide T-CPR to family members compared with friends and passengers. Twenty-one percent of callers made emergency calls after consulting with others (indirect call). In non-traumatic victims who underwent bystander CPR, 43% experienced the return of spontaneous circulation, and 5% were discharged with a mild disorder or no neurological abnormality.

Conclusions

We conclude that 95% of bystanders are willing to perform CPR under the T-CPR system, but we cannot conclude that bystander CPR may not affect the survival rate. These findings indicate that bystanders should be guided with T-CPR. (Hong Kong j.emerg. med. 2016;23:220-226)

The Relation between Hamstring Strain Injury and Physical Characteristics of Japanese Collegiate Sepak Takraw Players

The aim of this study was to investigate the injuries in Japanese collegiate sepak takraw players. We primarily focused on hamstring strain injury (HSI), and investigated the associated physical characteristics. The study included 77 Japanese collegiate sepak takraw players who were interviewed; data were collected regarding injuries sustained by them during the game within the past year. The hip range of motion (ROM) was measured. The total number of injuries was 48 in a year. The rate of HSI was the highest (31.3%) among all the injuries. All HSIs occurred in the dominant leg because of the sunback spike. Using the Mann-Whitney U test, significant differences in age and sport-related experience were observed between the injured group and uninjured group. Upon using logistic regression analysis, the presence of a HSI was found to be associated with the sport-related experience (adjusted odds ratio [OR], 0.30; 95% confidence interval [CI], 0.12-0.77) and the hip extension ROM (adjusted OR, 0.81; 95% CI, 0.66-0.99) after adjusting for sex, sport-related experience, and the hip ROM. HSI is the most common injury in Japanese collegiate sepak takraw players. Short sport-related experience and small hip extension ROM are related with the occurrence of HSI.

Sodium and Manganese Stoichiometry of P2-Type Na2/3 MnO2

To realize a reversible solid-state Mn(III/IV) redox couple in layered oxides, co-operative Jahn-Teller distortion (CJTD) of six-coordinate Mn(III) (t2g (3) -eg (1) ) is a key factor in terms of structural and physical properties. We develop a single-phase synthesis route for two polymorphs, namely distorted and undistorted P2-type Na2/3 MnO2 having different Mn stoichiometry, and investigate how the structural and stoichiometric difference influences electrochemical reaction. The distorted Na2/3 MnO2 delivers 216 mAh g(-1) as a 3 V class positive electrode, reaching 590 Wh (kg oxide)(-1) with excellent cycle stability in a non-aqueous Na cell and demonstrates better electrochemical behavior compared to undistorted Na2/3 MnO2 . Furthermore, reversible phase transitions correlated with CJTD are found upon (de)sodiation for distorted Na2/3 MnO2 , providing a new insight into utilization of the Mn(III/IV) redox couple for positive electrodes of Na-ion batteries.

Effective CpG DNA delivery using amphiphilic cycloamylose nanogels

Unmethylated CpG oligodeoxynucleotides induce inflammatory immune responses through cytokine production and have attracted increasing attention as an immunostimulator. However, there remains a challenging issue of the use of 'native CpG DNA'. In the present study, we prepared cationic nanometer-sized gels (nanogels) consisting of cycloamylose modified with cholesterol and diethylaminoethane to form hydrophobic cross-linking points and to add positively charged groups, respectively. The cationic nanogels and native CpG DNA formed nanometer-sized complexes. Complexes of native CpG DNA with cationic nanogels delivered native CpG DNA to macrophage-like cells and induced cytokine production. In addition, complexes of negative control oligonucleotides with cationic nanogels did not induce cytokine production, and the induction of cytokines using complexes of phosphorothioate-modified CpG with cationic nanogels was lower than that of native CpG DNA. These results suggest that the complex of native CpG DNA with cationic nanogels is a promising strategy for nucleic acid adjuvants.

Chronobiology and nutrition

Numerous long-term studies have investigated the circadian clock system in mammals, which organizes physiological functions, including metabolism, digestion, and absorption of food, and energy expenditure. Food or nutrition can be a synchronizer for the circadian clock systems, as potent as the external light-dark signal can be. Recent studies have investigated different kinds of food, frequency of consumption, and time of consumption for optimizing body clock and ensuring healthy habits. In this review, we discuss recent studies investigating chronobiology and nutrition, and then summarize available information as "Chrono-nutrition" for the development of a new standardized research strategy.

Biological clock dysfunction exacerbates contact hypersensitivity in mice

BACKGROUND

Immediate-type skin allergic reactions, such as passive cutaneous anaphylactic reaction, are associated with circadian rhythm, but the role of circadian mechanisms on delayed-type skin allergic reactions, such as contact hypersensitivity (CHS), remains uncertain. In mice, CHS, a T-cell-mediated immune response, is a classic model of human allergic contact dermatitis.

OBJECTIVES

  We investigated whether biological clock dysfunction affects CHS pathogenesis in CLOCK mutant mice compared with wild-type (WT) mice.

METHODS

 Mice were treated with 2,4,6-trinitro-1-chlorobenzene (TNCB) on the abdominal skin on day 0 (sensitization) and then treated with TNCB on the ears on day 5 (challenge).

RESULTS

We found that biological clock dysfunction resulted in severe inflammation. Ear swelling, serum immunoglobulin E level and mast cell number were significantly increased in CLOCK mutant mice compared with WT mice. These results provide evidence that CLOCK mutation promotes the T-helper type 2 immune response and exacerbates CHS. Corticosterone has a protective effect on CHS. The serum corticosterone level lost rhythmicity and showed a decreased daily level in CLOCK mutant mice compared with WT mice, supporting the exacerbating effect of CLOCK mutation on CHS. Adrenalectomy markedly worsened TNCB-induced CHS in WT mice but not in CLOCK mutant mice. In addition, dramatic dexamethasone-induced protection of CHS was observed in CLOCK mutant mice compared with WT mice.

CONCLUSIONS

 The present results suggest that circadian rhythm might be an important factor in the regulation of CHS via corticosterone rhythmicity and/or level.

Relationship between buccal mucosa ridging and viscoelastic behaviour of oral mucosa

The aim of this study was to clarify the relationship between the buccal mucosa ridging (BMR), which has been mentioned to be a clinical sign of clenching, and the viscoelastic behaviour of oral mucosa. Twenty-three people with BMR and 21 people without BMR participated as volunteers in this study. Measurements of viscoelastic behaviour were performed using a suction viscoelastic meter on central part of lower labial mucosa. A suction pressure of 300 hPa was applied for 2 s and then released for 2 s, and the time-dependent changes in the deformation of the mucosa over this 4 s were recorded as a deformation curve. Distensibility, remaining deformation and elastic recovery, which describe viscoelastic behaviour, were calculated by the deformation curve. These parameters were compared between groups with and without BMR. No significant difference was found in distensibility between the two groups (P=0·349). There were significant differences for the remaining deformation (P=0·012) and the elastic recovery (P=0·032), and the group with BMR showed higher remaining deformation and lower elastic recovery than the group without BMR. Based on these results, it clarified that the BMR is related to the mucosal viscoelastic behaviour, in particular remaining deformation and elastic recovery.

Influence of concentration of fragrances on salivary alpha-amylase

The objective is to reveal the influence of the concentration of fragrances on salivary biomarkers, which reflect the human stress system, in 15 female young healthy adults. Lavandula officinalis and Citrus aurantium were used as the test samples. Salivary biomarkers such as alpha-amylase activity (AMY), cortisol (CORT) and dehydroepiandrosterone (DHEA) were measured during baseline, inhalation and post-inhalation periods. Our results indicated that (i) a significant difference was not observed for the control and the 3 wt% test samples, however, the AMY was decreased by inhalation of the 1 wt% test samples (P < 0.05); (ii) AMY levels changed more significantly than did the hormone levels; (iii) a tendency of negative correlation was not observed between DHEA and CORT. It was considered that the time-course change of AMY might be a useful index of the inhalation of fragrances, which reflects the acute psychosomatic reactivity of humans.

Inactivation of atmospheric bacteria using lytic enzyme mixture

The mass of air breathed by a human per day is equivalent to 10-times the mass of food consumed in that time. However, fundamental safety measures for atmospheric bacterial control have not yet been implemented. The purpose of our research is to develop a cell wall Iytic filter using a cell wall Iytic enzyme, which can inactivate the bacteria in air that cause infectious diseases by decomposing their cell envelope. In this study, the use of Iytic enzyme mixture was suggested, including glycosidase, protease and lipase. The performance of the Iytic enzyme mixture was evaluated using lysozyme, a typical Iytic enzyme, as a control. The substrate that we used was Micrococcus luteus, a gram-positive bacteria. The experimental results showed that the use of the Iytic enzyme mixture exhibited a Iytic rate per hour that was 13 - 39% greater than the control. Furthermore, although there are some different phases during bacterium multiplication, the Iytic rate per hour improved for all of the phases when the Iytic enzyme mixture was used.

Benchmark experiments for cyclotron-based neutron source for BNCT

In the previous study, we found the feasibility of a cyclotron-based BNCT using the Ta(p,n) neutrons at 90 degrees bombarded by 50 MeV protons, and the iron, AlF(3), Al and (6)LiF moderators by simulations using the MCNPX code. In order to validate the simulations to realize the cyclotron-based BNCT, we measured the epithermal neutron energy spectrum passing through the moderators with our new spectrometer consisting of a (3)He gas counter covered with a silicon rubber loaded with (nat)B and polyethylene moderator and the depth distribution of the reaction rates of (197)Au(n,gamma)(198)Au in an acrylic phantom set behind the rear surface of the moderators. The measured results were compared with the calculations using the MCNPX code. We obtained the good agreement between the calculations and measurements within approximately 10% for the neutron energy spectra and within approximately 20% for the depth distribution of the reaction rates of (197)Au(n,gamma)(198)Au in the phantom. The comparison clarified a good accuracy of the calculation of the neutron energy spectrum passing through the moderator and the thermalization in a phantom. These experimental results will be a good benchmark data to evaluate the accuracy of the calculation code.

Chart analysis of body composition change among pre- and postadolescent Japanese subjects assessed by underwater weighing method

OBJECTIVE

To examine the effect of age on the relationship between fat-free mass (FFM) and fat mass (FM), and fat-free mass index (FFMI) and fat mass index (FMI) by applying body composition chart analysis on pre- and postadolescent Japanese subjects.

SUBJECTS AND METHOD

A sample of 516 children (244 boys and 272 girls) ranging in age from 11 to 17 y and 840 adults (288 male and 552 female subjects) ranging in age from 18 to 59 y were studied to determine a body composition by an underwater weighing method. FMI and FM were put on an x- and y-axis in body composition chart 1, and FFMI (FFM/ height(2)) and FMI (FM/height(2)) were taken on an x- and y-axis in body composition chart 2.

RESULTS

In body composition chart 1, the plots for male subjects stayed flat from 11 to 14 y and after that a steady growth of FFM concurring with the FM growth was observed. During the adult stage, steady increments of FM and gradual decreases of FFM were observed. In body composition chart 2, steady increases of FFMI and gradual decreases of FMI were indicated in the male preadolescent period. In the adult stage, FFMI decreased year by year, although the FMI continued to increase. In female subjects, a conspicuous increase of FMI was observed throughout all periods of the present subjects. After middle age, the decline of FFMI was characteristically demonstrated in the chart.

CONCLUSION

The relationships between FFM and FM are characteristically delineated on the body composition charts demonstrating clear gender differences. The change of body mass index was not reflecting the change of adiposity level in male subjects, although it was occurring along with the changes of the adiposity level in female subjects.

Over-expression system for secretory phospholipase D by Streptomyces lividans

The structural gene for phospholipase D (PLD) of an actinomycete, Streptoverticillium cinnamoneum, together with its promoter region was introduced into Streptomyces lividans using a shuttle vector-pUC702-for Escherichia coli and S. lividans. The transformant was found to secrete a large amount of PLD (about 2.0x10(4) U/l, 42 mg/l) when cultured in a jar fermentor. Both an initial glucose concentration of 17.5 g/l and the feeding of carbon and nitrogen sources are effective for efficient secretion of PLD; under these culture conditions, the amount of PLD secreted reached a maximum level (about 5.5x10(4) U/l, 118 mg/l) after about 60 h. In contrast to the original producer, Stv. cinnamoneum, which secretes only a small amount of PLD (about 1.1x10(3) U/l, 2 mg/l) along with other extracellular proteins, this heterologous expression system is markedly more efficient in production of secretory PLD.