Trends and Outcomes of Early Rehabilitation in the Intensive Care Unit for Patients With Cardiovascular Disease: A Cohort Study With Propensity Score-Matched Analysis

BACKGROUND

The effectiveness of acute-phase cardiovascular rehabilitation (CR) in intensive care settings remains unclear in patients with cardiovascular disease (CVD). This study aimed to investigate the trends and outcomes of acute-phase CR in the intensive care unit (ICU) for patients with CVD, including in-hospital and long-term clinical outcomes.

METHOD

This retrospective cohort study reviewed a total of 1,948 consecutive patients who were admitted to a tertiary academic ICU for CVD treatment and underwent CR during hospitalisation. The endpoints of this study were the following: in-hospital outcomes: probabilities of walking independence and returning home; and long-term outcomes: clinical events 5 years following hospital discharge, including all-cause readmission or cardiovascular events. It evaluated the associations of CR implementation during ICU treatment (ICU-CR) with in-hospital and long-term outcomes using propensity score-matched analysis.

RESULTS

Among the participants, 1,092 received ICU-CR, the rate of which tended to increase with year trend (p for trend <0.001). After propensity score matching, 758 patients were included for analysis (pairs of n=379 ICU-CR and non-ICU-CR). ICU-CR was significantly associated with higher probabilities of walking independence (rate ratio, 2.04; 95% CI 1.77-2.36) and returning home (rate ratio, 1.22; 95% CI 1.05-1.41). These associations were consistently observed in subgroups aged >65 years, after surgery, emergency, and prolonged ICU stay. ICU-CR showed significantly lower incidences of all-cause (HR 0.71; 95% CI 0.56-0.89) and cardiovascular events (HR 0.69; 95% CI 0.50-0.95) than non-ICU-CR.

CONCLUSIONS

The implementation of acute-phase CR in ICU increased with year trend, and is considered beneficial to improving in-hospital and long-term outcomes in patients with CVD and various subgroups.

Association Between Nonadherence and Transient Hyperuricemia in Pediatric Kidney Transplantation

BACKGROUND

Nonadherence among pediatric transplant recipients is a significant problem that reduces graft survival and leads to poor kidney graft outcomes. It is, however, extremely difficult to detect during a regular follow-up. This study, therefore, aimed to investigate the risk factors involved in nonadherence, focusing on unexplained transient hyperuricemia in pediatric kidney transplant (KTx) recipients at a single pediatric center.

METHODS

This retrospective study included 167 patients who underwent KTx at our pediatric center. A Cox proportional hazards analysis was performed to evaluate the risk of nonadherence using the following factors: age, sex, body mass index SD score, transient hyperuricemia, hypertension, and follow-up period.

RESULTS

Nonadherence was identified in 19 patients (11%), with the average (SD) age and post-KTx duration at diagnosis being 17.21 (4.73) years and 79.21 (38.77) months, respectively. Thirty-four patients (20%) were diagnosed with transient hyperuricemia at a median of 14 months after KTx. On multivariate Cox regression analysis, transient hyperuricemia was the only independent risk factor for nonadherence after KTx.

CONCLUSIONS

Transient hyperuricemia was identified as one of the risk factors for nonadherence after KTx; therefore, careful monitoring for transient hyperuricemia may allow early detection of nonadherence.

Detailed Changes in Oxygenation following Awake Prone Positioning for Non-Intubated Patients with COVID-19 and Hypoxemic Respiratory Failure—A Historical Cohort Study

Few studies have reported on the effectiveness of awake prone therapy in the clinical course of coronavirus disease (COVID-19) patients. This study aimed to investigate the effects of awake prone therapy during spontaneous breathing on the improvement of oxygenation over 3 weeks for COVID-19 acute respiratory failure. Data of consecutive COVID-19 patients with lung disorder with a fraction of inspired oxygen (FIO2) ≥ 0.4 and without tracheal intubation were analyzed. We examined changes in SpO2/FIO2, ROX index ((SpO2/FIO2)/respiratory rate) and the seven-category ordinal scale after the initiation of FIO2 ≥ 0.4 and compared these changes between patients who did and did not receive prone therapy. Of 58 patients, 27 received awake prone therapy, while 31 did not. Trend relationships between time course and change in SpO2/FIO2 and ROX index were observed in both groups, although a significant interaction in the relationship was noted between prone therapy and change in SpO2/FIO2 and ROX index. The seven-category ordinal scale also revealed a trend relationship with time course in the prone therapy group. The awake prone therapy was significantly associated with a lower rate of tracheal intubation. In patients with COVID-19 pneumonia treated with FIO2 ≥ 0.4, awake prone therapy may improve oxygenation within two weeks.

Validation of National Early Warning Score for predicting 30-day mortality after rapid response system activation in Japan

Aim

Although rapid response systems (RRS) are used to prevent adverse events, Japan reportedly has low activation rates and high mortality rates. The National Early Warning Score (NEWS) could provide a solution, but it has not been validated in Japan. We aimed to validate NEWS for Japanese patients.

Methods

This retrospective observational study included data of 2,255 adult patients from 33 facilities registered in the In‐Hospital Emergency Registry in Japan between January 2014 and March 2018. The primary evaluated outcome was mortality rate 30 days after RRS activation. Accuracy of NEWS was analyzed with the correlation coefficient and area under the receiver operating characteristic curve. Prediction weights of NEWS parameters were then analyzed using multiple logistic regression and a machine learning method, classification and regression trees.

Results

The correlation coefficient of NEWS for 30‐day mortality rate was 0.95 (95% confidence interval [CI], 0.88–0.98) and the area under the receiver operating characteristic curve was 0.668 (95% CI, 0.642–0.693). Sensitivity and specificity values with a cut‐off score of 7 were 89.8% and 45.1%, respectively. Regarding prediction values of each parameter, oxygen saturation showed the highest odds ratio of 1.36 (95% CI, 1.25–1.48), followed by altered mental status 1.23 (95% CI, 1.14–1.32), heart rate 1.21 (95% CI, 1.09–1.34), systolic blood pressure 1.12 (95% CI, 1.04–1.22), and respiratory rate 1.03 (95% CI, 1.05–1.26). Body temperature and oxygen supplementation were not significantly associated. Classification and regression trees showed oxygen saturation as the most heavily weighted parameter, followed by altered mental status and respiratory rate.

Conclusions

National Early Warning Score could stratify 30‐day mortality risk following RRS activation in Japanese patients.

Post-intensive care syndrome as a predictor of mortality in patients with critical illness: A cohort study

Introduction

The post-intensive care syndrome (PICS) encompasses multiple, diverse conditions, such as physical disability, cognitive impairment, and depression. We sought to evaluate whether conditions within PICS have similar associations with mortality among survivors of critical illness.

Materials and methods

In this retrospective cohort study, we identified 248 critically ill patients with intensive care unit stay ≥72 hours, who underwent PICS evaluation. Patients with disability in activities of daily living, cognitive impairment, or depression before hospitalization were excluded. We defined PICS using established measures of physical disability (usual gait speed), cognitive impairment (Mini-Cog test), and depression (Patient Health Questionnaire-2) at hospital discharge. The endpoint was all-cause mortality.

Results

Patients had a median age of 69 years and Acute Physiology and Chronic Health Evaluation (APACHE) II score of 16. One hundred thirty-two patients were classified as having PICS, and 19 patients died. 81/248 (34%) patients had physical disability, 42/248 (19%) had cognitive impairment, and 44/248 (23%) had depression. After adjusting for covariates on multivariable Cox regression analyses, PICS was significantly associated with all-cause mortality (hazard ratio [HR] 3.78, 95% confidence interval [CI] 1.02 – 13.95; P = 0.046). However, the association between PICS and all-cause mortality was related to physical disability and cognitive impairment (P = 0.001 and P = 0.027, respectively), while depression was not (P = 0.623).

Conclusion

While PICS as a syndrome has been useful in gaining attention to the sequelae of critical illness, its relationship with long-term mortality is driven largely by physical disability and cognitive impairment and not depression.

The characteristics, types of intervention, and outcomes of postoperative patients who required rapid response system intervention: a nationwide database analysis

Purpose

Improving the safety of general wards is a key to reducing serious adverse events in the postoperative period. We investigated the characteristics, treatment, and outcomes of postoperative patients managed by a rapid response system (RRS) in Japan to improve postoperative management.

Methods

This retrospective study analyzed cases requiring RRS intervention that were included in the In-Hospital Emergency Registry in Japan. We analyzed data reported by 34 Japanese hospitals between January 2014 and March 2018, mainly focusing on postoperative patients for whom the RRS was activated within 7 days of surgery. Non-postoperative patients, for whom the RRS was activated in all other settings, were used for comparison as necessary.

Results

There were 609 (12.7%) postoperative patients among the total patients in the registry. The major criteria were staff concerns (30.2%) and low oxygen saturation (29.7%). Hypotension, tachycardia, and inability to contact physicians were observed as triggers significantly more frequently in postoperative patients when compared with non-postoperative patients. Among RRS activations within 7 days of surgery, 68.9% of activations occurred within postoperative day 3. The ordering of tests (46.8%) and fluid bolus (34.6%) were major interventions that were performed significantly more frequently in postoperative patients when compared with non-postoperative patients. The rate of RRS activations resulting in ICU care was 32.8%. The mortality rate at 1 month was 16.2%.

Conclusion

Approximately, 70% of the RRS activations occurred within postoperative day 3. Circulatory problems were a more frequent cause of RRS activation in the postoperative group than in the non-postoperative group.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00540-021-02900-4.

Rapid response system in Japanese outpatient departments based on online registry: Multicentre observational study

Aim

The rapid response system (RRS) has become well known as a patient safety system to reduce adverse in-patient events, and it is also required to respond to patients in the outpatient department. However, only few studies have reported on the RRS in the outpatient department. We analysed the current status of the RRS in the outpatient department based on a multicentre online registry in Japan.

Methods

This is a prospective multicentre observational study. Among the cases registered in the RRS online registry from January 2014 to March 2018, cases from the outpatient department, consisting of the general outpatient department, radiation department, dialysis department, endoscope department, rehabilitation department, and the surrounding areas were eligible for this study.

Results

A total of 6784 cases were registered, and 1022 cases were included. The main reason for activation was altered mental status (39.1%). Incomplete vital sign recording at activation was 67.0%, whereas body temperature (57.0%) and respiratory rate (36.4%) deficits were frequent. The most common intervention during RRS activation was fluid bolus (38.2%) and oxygen supplementation (30.9%). The general outpatient department accounted for nearly half of the activation locations. The 30-day mortality rate for the location was significantly higher in the dialysis department (P < 0.001).

Conclusions

We have reported the first study of RRSs in outpatient departments at multicentre facilities in Japan. The difference in the mortality rate for the location was clarified. Future tasks will involve clarifying the RRS outcome indicators in the outpatient department and examining the effectiveness thereof.

Influence of obesity and epicardial fat on the progression of electrical and structural remodeling in a canine obese rapid atrial pacing model

Background

Metabolic syndrome is a cluster of conditions including obesity, insulin resistance, hypertension, and abnormal cholesterol, which increases the cardiovascular risk. Metabolic syndrome or obesity has been reported to provide systemic inflammation and oxidative stress. Increased epicardial fat volume is a manifestation of obesity or metabolic syndrome. Those systemic and local conditions related to obesity or metabolic syndrome have been linking to the risk of atrial fibrillation (AF). The underlying mechanisms of obesity linking epicardial fat to AF progression have not been fully examined.

Purpose

To investigate the impact of obesity linked to epicardial fat on electrophysiologic and anatomical AF substrates.

Methods

Twenty dogs aged 3 years were divided into four groups (n=5 per each): normal diet for over 20 weeks (control group [median body weight: 12.0 kg]), rapid atrial pacing (RAP) for last 4–15 (median 8) weeks during a normal diet for the same period (RAP group [10.5 kg]), high-fat diet (HFD) maintained for over 20 weeks without RAP (MetS group [16.0 kg]), and RAP for last 4–12 (median 6) weeks during HFD maintained for 24 weeks (MetS-RAP group [17.0 kg]), respectively. Activation/voltage maps of the atria during sinus rhythm were created with Ensite NavX mapping system. The effective refractory period (ERP) at 5 left atrial (LA) and pulmonary vein (PV) sites (LA appendage [LAA], LA body, right and left superior PVs, and inferior PV), and AF inducibility by burst LAA pacing were determined. At study completion, hearts were excised for histopathological and gene expression analyses.

Results

The LA pressure was more significantly increased in MetS than the MetS-RAP, RAP, and control groups (22.5 [17–28.8] mmHg vs. 14.0 [10.5–16.3] mmHg, 10.5 [7.4–17.2] mmHg and 10.7 [9.6–13.5] mmHg, respectively, P&lt;0.05). The LA/PV ERP at a basic cycle length of 400 ms was shorter in the MetS-RAP and RAP than MetS and control groups (118±39 ms and 122±44 ms vs. 136±18 ms and 155±39 ms, respectively, P&lt;0.05). Short duration AF was more induced in the MetS and MetS-RAP than RAP and control groups (3 [0–5.5] sec and 2 [0.5–3.5] sec vs. 0 [0–4.5] sec and 0 [0–0] sec, P&lt;0.05). Histological examinations showed the fatty infiltration extending from epicardial fat increased more in the Mets and Mets-RAP than RAP and control groups (Figure). The Fibronectin 1 and collagen I/III mRNA levels increased more in the MetS-RAP and AF than MetS and control groups.

Conclusions

AF vulnerability was associated with increased LA pressures and fibrofatty infiltration from epicardial fat in the MetS group, and with fibrofatty infiltration from epicardial fat with subtle fibrosis in the MetS-RAP group. This suggested that fibrofatty infiltration and epicardial fat plays an important role in AF pathogenesis in obese patients.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid for Scientific Research (KAKENHI)

Preoperative sepsis is a predictive factor for 30-day mortality after major lower limb amputation among patients with arteriosclerosis obliterans and diabetes

BACKGROUND

While many patients with lower limb ischemia also have severe infections, few studies have investigated whether the presence of preoperative sepsis affects patient prognosis following lower limb amputation (LLA). Therefore, we investigated the factors (including sepsis as defined in SEPSIS-3) that contribute to the acute mortality rate in patients who underwent LLA due to arteriosclerosis obliterans (ASO) or diabetes mellitus (DM).

METHODS

In this retrospective, single-center, 10-year chart review study, 122 adult patients who underwent LLA due to ASO and/or DM were identified from 56,438 surgery cases. Patient characteristics, including co-morbidities, surgical conditions, the presence/absence of sepsis, and acute physiological condition after surgery, were investigated in patients who died within 30 days of LLA and those who survived. Univariate analysis between groups was performed using the chi-square test. Comparisons of age and American Society of Anesthesiologists-Physical Status classification between groups were performed using the Mann-Whitney U test. Risk factors for 30-day mortality after LLA were examined using stepwise logistic regression (backward elimination). Statistical results were considered significant at P < 0.05.

RESULTS

Eight cases of mortality (6.6%) were found; we identified the causes as sepsis, myocardial infarction, fatal arrhythmia, and mesenteric artery occlusive disease in 5 (62.5%), 1 (12.5%), 1 (12.5%), and 1 (12.5%) cases, respectively. Using univariate analysis, we identified that age (≥74), delirium, sepsis, intensive care unit admission, non-DM (ASO only), hemodialysis, and acute kidney injury were significantly higher in the mortality group. In logistic regression analysis, non-DM (odds ratio [OR]: 35.2, 95% confidence interval [CI]: 2.8-432) and sepsis (OR: 80.7, 95% CI: 6.7-959) were potential risk factors for 30-day mortality.

CONCLUSIONS

This study suggests that cases resulting in amputation due to ASO pathology alone might have poor prognosis and that preoperative sepsis can increase perioperative mortality; hence, the decision to amputate must be considered before the development of sepsis.

First report based on the online registry of a Japanese multicenter rapid response system: a descriptive study of 35 institutions in Japan

AIM

Although the concept of a rapid response system (RRS) has been gradually accepted in Japan, detailed information on the Japanese RRS is not well known. We provide the first report of the RRS epidemiological situation based on 4 years of RRS online registry data.

METHODS

This is a prospective observational study. All patients registered between January 2014 and March 2018 were eligible for this study. Data related to RRS including physiological measurements were recorded. The mortality rates after rapid response team/medical emergency team (RRT/MET) intervention and after 30 days were recorded as outcomes.

RESULTS

In total, 6,784 cases were registered at 35 facilities. Cancer (23.1%) was the most common existing comorbidity. Limitation of medical treatment was identified in 12.7% of the cases. The respiratory category was most frequently activated in 41.3% of the cases. Only two institutions had received more than 15 calls per 1,000 admissions. During RRT/MET intervention, death occurred in 3.6% and transfers to intensive care units occurred in 28.2% of the cases. After 30 days, the mortality rate was significantly higher in the night than in the day shift (30.7% versus 20.4%, respectively, P < 0.01).

CONCLUSIONS

We report the first epidemiological study of RRS in Japan. Japanese facilities had a very low rate of RRT/MET calls and a higher mortality rate in the night than in the day shift. Further promotion to increase the number of calls and implementation of a 24-h RRT/MET is required.

P4384Noninvasive and novel method to evaluate left ventricular contractility using pressure-volume loop area obtained by 3-dimensional speckle tracking echocardiography

Introduction

Left ventricular (LV) pressure-volume (P-V) loop area reflects stroke work (SW), but clinical use of this index is limited by the need of invasive pressure measurement. A noninvasive method to obtain LV pressure-strain loop was recently introduced to assess myocardial work (MW). The minimum LV diastolic pressure (mLVP) was reported to have a strong correlation with Tau and we reported that Tau was noninvasively evaluated by speckle tracking echocardiography (STE).

Purpose

We sought to evaluate the impact of preload change by leg lifts on LV SW noninvasively obtained by the novel method and to examine the utility to assess LV contractility by SW and end-diastolic (ED) volume relation (SW-VED).

Methods

Thirty six controls (age 71±10) and 30 patients with heart failure with reduced ejection fraction (EF) <50% (HF) (age 73±6) were enrolled. LV pressure in a cardiac cycle was estimated using systolic blood pressure (SBP), minimum diastolic pressure (mDP) and ED pressure (EDP) by utilizing the profile of an empiric, normalized reference curve. The mDP and EDP were estimated as (Tau − 33.7)/2.06 and as 12.3 − 10.1 x Log (left atrial active emptying function/minimum volume) as we reported. LVSW was obtained by P-V loop by the combination of these pressures and LV volume using 3-D STE.

Results

LVEF and longitudinal strain in HF before leg up by 3D-STE were lower compared to normal (LVEF; normal: 58±5 vs HF: 39±10*% and strain; −12±3 vs −8±3%*, *p<0.05 vs normal). LVEF was increased after leg up by 7±6% in normal and by 8±8% in HF associated with increased LVED volume (normal: 84±24 to 90±24 and HF: 124±36* to 136±42*ml). LV MW and SW in HF before leg up were lower compared to normal (MW: 1790±412 vs 1002±432*mmHg% and SW: 3946±1682 vs 3352±1026mmHgml). LV SW increased after leg up by 26±19% in normal and by 25±20% in HF. LV SW-VED in normal was greater than HF (241±151 vs 90±54*).

Conclusion

LV SW noninvasively obtained by P-V loop area was increased after leg up in both normal and HF but SW-VED in HF was smaller than normal, indicating reduced contractility in HF. This noninvasive method may be a new echocardiographic approach for quantification of LV SW and contractility.

P2474Noninvasive estimation of pulmonary capillary wedge pressure by novel 3D speckle tracking echocardiography and validation study by cardiac catheterization

Background

We previously reported that pulmonary capillary wedge pressure (PCWP) was noninvasively evaluated by 2D speckle tracking echocardiography (STE). Recently, novel software was introduced to examine volume and function of left ventricular and left atrium (LA) by 3D-STE automatically.

Purpose

We sought to compare the PCWP estimated by conventional 2D-STE (2D-ePCWP) and by novel 3D-STE (3D-ePCWP), and validate those values by cardiac catheterization.

Methods

Echocardiography and catheterization were performed in 29 patients (age 72±2) (7 ischemic heart disease, 2 hypertensive heart disease, 5 dilated cardiomyopathy, 12 valvular heart disease and 3 primary pulmonary hypertension).The ePCWP (mmHg) is noninvasively obtained as 10.8 − 12.4 x Log (left atrial active emptying function/minimum volume) as we previously reported. Echocardiography was performed just before the catheterization and we analyzed the 2D and 3D data by novel off-line software. 3D data was automatically analyzed and the border settings were fixed at default (ES60, ED30) (Figure).

Results

2D-ePCWP and 3D-ePCWP had a good correlation with PCWP invasively obtained by catheterization (r=0.87 and 0.83, respectively, both p<0.001). There was an excellent correlation between 2D-ePCWP and 3D-ePCWP (r=0.94, p<0.001) and there was a good correlation between 2D-LA volume index and 3D- LA volume index (r=0.80, p<0.001). Bland-Altman analysis revealed a good agreement between 2D-ePCWP and 3D-ePCWP, and between 2D-ePCWP and 3D-ePCWP without fixed and proportional bias.

Conclusion

This study demonstrated that PCWP might be noninvasively assessed by not only 2D-STE but also 3D-STE with reasonable accuracy and 3D-STE might have utility and value in the routine clinical practice.

P4351Validation by cardiac catheterization of noninvasive evaluation of left ventricular chamber and myocardial stiffness as a diastolic function using speckle tracking echocardiography

Background

Left ventricular (LV) diastolic function is mainly composed of LV relaxation and LV stiffness. We reported that pulmonary capillary wedge pressure (ePCWP) and LV relaxation assessed by Tau (eTau) are noninvasively evaluated by speckle tracking echocardiography (STE). The minimum LV diastolic pressure (mLVP) was reported to have a strong correlation with Tau. Therefore, LV chamber stiffness (c-stiffness) may be assessed with the use of two LV diastolic pressure-volume coordinates: the mLVP and volume and the end-diastolic pressure (EDP) and volume.

Purpose

We sought to noninvasively assess LV stiffness using STE and validate the value by cardiac catheterization.

Methods

Echocardiography and catheterization were performed in 124 patients (age 72±8) (70 angina pectoris, 20 prior myocardial infarction, 19 hypertensive heart disease, 11 congestive heart failure and 4 paroxysmal atrial fibrillation). The ePCWP (mmHg) is noninvasively obtained as 10.8 − 12.4 × Log (left atrial active emptying function/minimum volume) and the eTau (ms) is obtained as isovolumic relaxation time/(ln 0.9 × systolic blood pressure − ln ePCWP) as previously reported. The mLVP (e-mLVP) was estimate using Tau. The estimated EDP (e-EDP) was calculated as 12.3 − 10.1 × Log (left atrial active emptying function / minimum volume). LV c-stiffness (mmHg/ml) was calculated as LV pressure change (from mLVP to EDP) obtained by catheterization divided by LV volume change during diastole which equals to stroke volume by echocardiography. Estimated c-stiffness (e-c-stiffness) was noninvasively obtained using e-mLVP and e-EDP. Furthermore, LV myocardial stiffness (m-stiffness) was calculated by LVED stress / LV longitudinal strain by STE, where LV stress (kdynes/cm2) was calculated as 0.334 × pressure × dimension / [thickness (1 + thickness/dimension)]. The estimated m-stiffness (e-m-stiffness) was calculated using e-EDP.

Results

The eTau and e-EDP estimated by STE had a good correlation with Tau and EDP invasively obtained by catheterization (r=0.75 and 0.63, respectively, both p<0.001). There was a good correlation between Tau and mLVP (Tau = 2.06 mLVP + 33.7, r=0.70). The estimated LVED stress had good correlation with ED stress obtained by catheterization (r=0.77, p<0.001). The e-c-stiffness and e-m-stiffness had a good correlation with those obtained by catheterization (e-c-stiffness; 0.116±0.07 and c-stiffness; 0.115±0.06, r=0.603, e-m-stiffness; 0.81±0.41 and m-stiffness; 0.85±0.45, r=0.89, respectively). Bland-Altman analysis revealed a good agreement between e-c-stiffness and c-stiffness, and between e-m-stiffness and m-stiffness without fixed and proportional bias.

Conclusion

This study demonstrated that LV stiffness may be noninvasively assessed by STE with reasonable accuracy and may have utility and value in the routine clinical practice for the diagnosis and treatment in patients with diastolic dysfunction.

IMPACT ON ABSORBED DOSE RATE IN AIR IN KANTO REGION BY FUKUSHIMA DAIICHI NUCLEAR POWER PLANT ACCIDENT

Absorbed dose rates in air were measured for the whole area of the Kanto region in 2015, 2016 and 2017 (n = 31 147). The mean absorbed dose rates in air for each prefecture measured by car-borne surveys were from 44 to 67 nGy h-1 (13-289 nGy h-1). The absorbed dose rate in air from artificial radionuclides (134Cs + 137Cs) measured by fixed-point observation (n = 507) was from 1 to 14 nGy h-1 (0-105 nGy h-1), and meaning that the contribution ratios of 134Cs and 137Cs were 3-22%. The deposited location of artificial radionuclides was less than 1000 m from ground level and depended on the topography, wind direction and precipitation field.

Abstract P2-08-50: Elevated levels of serum tumor marker p53 is a prognostic parameter and a monitoring biomarker for patients who had undergone surgical resection in breast cancer

Background

Elevated levels of serum tumor maker p53 antibody is expected as an indicator of early diagnosis and a parameter of recurrence in breast cancer. P53 mutation accounts for 20% to 35% in all breast cancer patients. Preoperative high level of anti-p53 antibody in breast cancer patients tend to associate with worse prognosis. This study investigated the prognostic value of preoperative serum p53 levels, and the significance as a biomarker to evaluate a recurrence after surgical resections in breast cancer.

Methods

Preoperative serum p53 concentration levels were measured in total of 259 breast cancer patients, who had undergone either a total mastectomy or a partial mastectomy, through 2010 to 2015 in our facility. Patients with elevated levels of p53 (29 patients) and normal levels of p53 (230 patients) were compared to analyze the association of a marker level with the prognosis and the indication to diagnose recurrence in breast cancer.

Results

Elevated serum level of p53 mutation was identified in 29 (11%) patients. The size of tumor, staging, and pathology did not associate with the level of p53. Patients with elevated serum level of p53 correlated to the high score of nuclear grade (NG2 and NG3) and the high percentage of Ki-67 (&gt;14%), which leading to the worse prognosis. Triple negative breast cancer was the major molecular subtype in the group of high level of p53 comparing with the group of low level of p53. Survival analysis using the Kaplan-Meier method were performed to examine DFS and OS of high serum level of p53 patients. Patients with high level of p53 were significantly showed worse DFS than a normal p53 group. Serum level of p53 was also reflected to the recurrence and metastasis of postoperative breast cancer. There were three patients, who had local recurrences and metastasis, in the group of high levels of p53. Their serum levels of p53 were re-elevated as emerging the local recurrence and metastasis once they had gotten the normal serum levels of p53 after surgical resections. It showed that the increasing of the level of p53 was reflected to the recurrence and metastasis of tumors after surgical resections in breast cancer.

Conclusions

This study suggests that preoperative serum level of p53 can be an independent prognostic parameter and a monitoring biomarker for breast cancer.

Citation Format: Arai M, Nagata T, Sekine S, Baba H, Moriyama M, Hashimoto I, Fujii T. Elevated levels of serum tumor marker p53 is a prognostic parameter and a monitoring biomarker for patients who had undergone surgical resection in breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-08-50.

Abstract P2-01-22: KLF4 improve prognosis of triple negative breast cancer by suppression of epitherial mesenchymal transition

Background

Triple negative breast cancer (TNBC) is highly malignant and prone to metastasis and relapse, and therefore has poorer prognosis than other sub-types. The mechanism of higher malignancy of TNBC has not been sufficiently elucidated. KLF4is reported to be a transcription factor that is associated with both tumor suppression and oncogenesis. We have reported that breast cancer patients with strong expression of KLF4 had better prognosis, especially in TNBC patients. And here we report that KLF4 negatively regulates the metastasis and growth of TNBC.

Methods

We assessed the expression levels of KLF4 in 84 patients with TNBC by immunohistochemical staining and studied the patterns of metastasis/recurrence clinicopathologically. The overall survival (OS) rate and the disease free survival (DFS) rate after surgery was calculated by Kaplan-Maier method. In addition, circulating tumor cells (CTCs) in the peripheral blood of TNBC patients were identified and compared with primary lesions in terms of KLF4 expression. Moreover, the expression of KLF4 was inhibited by transfecting cultured TNBC cells (MDA-MB231) with the small interfering RNA (siRNA) of KLF4 to analyze the effects of KLF4 on cell proliferation and epithelial-mesenchymal transition (EMT)-like changes. For the proliferation assay, measurements were made by MTT assays. Cell migration and invasion assays of KLF4 suppressed TNBC cells were also examined. Total RNA was extracted from these cells, cDNA was synthesized, and used for the quantitative polymerase chain reaction (qPCR) analysis.

Results

In the 84 TNBC patients, higher KLF4 expression was associated with significantly better OS and DFS. An analysis of KLF4 expression in CTCs of the TNBC patients showed that KLF4 expression was lower in CTCs than in primary cancer lesions. TNBC cells (MDA-MB231) that were transfected the KLF4 siRNA exhibited a greater ability to growth than controls. These cells also underwent EMT-like changes with reduced expression of epithelial factors such as E-cadherin. Treating these TNBC cells with eribulin resulted a reduction of the expression of stem cell/EMT markers.

Conclusion

TNBC patients with reduced KLF4 expression had poor outcomes. The results of our experiments suggest the expression of KLF4 is one of the important factors that inhibit the EMT and growth of TNBC.

Citation Format: Nagata T, Sekine S, Arai M, Fujii T. KLF4 improve prognosis of triple negative breast cancer by suppression of epitherial mesenchymal transition [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-01-22.

Microscopic gain analysis of modulation-doped GeSn/SiGeSn quantum wells: epitaxial design toward high-temperature lasing

Threshold carrier densities of GeSn quantum well (QW) lasers and the physical reason of low-temperature lasing of current GeSn laser are investigated through the comparison of threshold carrier densities of conventional III-V QW lasers. Electrons distributed over L-band is the main cause of decreased gain for GeSn QWs. To increase the gain (and improve the laser characteristics), a modulation-doped GeSn QW is proposed and the material gain is analyzed based on many-body theory for both qualitative and quantitative simulation. Significant gain increase can be expected for n-type modulation doping QWs. The doping condition for elevated temperature lasing is discussed and it was found that material gain curve similar to III-V QW is obtained for GeSn QW with n-type modulation doping of 6 × 10¹⁸ cm^-3. It was also found that unlike III-V QW lasers, n-type modulation doping is more effective for high-speed operation in terms of differential gain than p-type modulation doping.

Randomized phase III and extension studies: efficacy and impacts on quality of life of naldemedine in subjects with opioid-induced constipation and cancer

BACKGROUND

The efficacy and safety of naldemedine (a peripherally acting µ-opioid receptor antagonist) for opioid-induced constipation (OIC) in subjects with cancer was demonstrated in the primary report of a phase III, double-blind study (COMPOSE-4) and its open-label extension (COMPOSE-5). The primary end point, the proportion of spontaneous bowel movement (SBM) responders, was met. Here, we report results from secondary end points, including quality of life (QOL) assessments from these studies.

PATIENTS AND METHODS

In COMPOSE-4, eligible adults with OIC and cancer were randomly assigned 1:1 to receive once-daily oral naldemedine 0.2 mg (n = 97) or placebo (n = 96) for 2 weeks, and those who continued on to COMPOSE-5 received naldemedine for 12 weeks (n = 131). Secondary assessments in COMPOSE-4 included the proportion of complete SBM (CSBM) responders, SBM or CSBM responders by week, and subjects with ≥1 SBM or CSBM within 24 h postinitial dose. Changes from baseline in the frequency of SBMs or CSBMs per week were assessed at weeks 1 and 2. Time to the first SBM or CSBM postinitial dose was also evaluated. In both studies, QOL impact was evaluated by Patient Assessment of Constipation-Symptoms (PAC-SYM) and PAC-QOL questionnaires.

RESULTS

Naldemedine improved bowel function for all secondary efficacy assessments versus placebo (all P ≤ 0.0002). The timely onset of naldemedine activity versus placebo was evidenced by median time to the first SBM (4.7 h versus 26.6 h) and CSBM (24.0 h versus 218.5 h) postinitial dose (all P < 0.0001). In COMPOSE-4, significant differences between groups were observed with the PAC-SYM stool domain (P = 0.045) and PAC-QOL dissatisfaction domain (P = 0.015). In COMPOSE-5, significant improvements from baseline were observed for overall and individual domain scores of PAC-SYM and PAC-QOL.

CONCLUSIONS

Naldemedine provided effective and timely symptomatic relief from OIC and improved the QOL of subjects with OIC and cancer. TRIAL REGISTRATION ID: www.ClinicalTrials.jp: JAPIC-CTI-132340 (COMPOSE-4) and JAPIC-CTI-132342 (COMPOSE-5).

Abstract PD1-09: High incidence rate of occult cancer in risk reducing mastectomy specimens despite thorough assessment with breast MRI and ultrasound-findings from the hereditary breast and ovarian cancer registration 2016 in Japan

Introduction:One of the preemptive strategies for Hereditary Breast and Ovarian Cancer (HBOC) is prophylactic surgery. Data for risk reducing mastectomy (RRM) clearly showed a risk reduction of more than 90% for breast cancer.

Method: We report here the statistical results of the HBOC registration up to 2016. The subjects of this study were those who underwent BRCA1/2 genetic testing during the study period, at 7 medical institutions.

Results: A total of 1527 probands underwent BRCA testing; 1125 cases (73.7%) were negative for BRCA1/2 mutation, and 297 cases (19.5%) were positive, while 105 cases (6.9%) had uncertain results. Among the 297 cases with positive results, 157 cases (10.3%) were positive for BRCA1, 139 cases (9.1%) for BRCA2, and 1 case (0.1%) was positive for both.The mean age at breast cancer diagnosis was 41.7 years in BRCA1/2 mutation positive and 45.8 years in negative cases. In comparison to the National Registration for Breast Cancer Incidence 2011 in Japan (n=72,472), breast cancer with BRCA mutations occurred at a younger age. Among 359 cases of triple negative breast cancer, 101 cases (28.3%) were BRCA1 mutation positive while 18 cases (5.0%) were BRCA2 mutation positive.

Three hundred seventy cases underwent genetic testing prior to surgery, as a deciding factor for the surgical procedure. Among BRCA mutation positive cases, 58 cases (87.9%) chose to undergo total mastectomy, and 8 cases (12.1%) chose breast conserving surgery (BCS); on the other hand, 141 cases (46.4%) of BRCA mutation negative cases chose total mastectomy and 158 cases (52.0%) chose BCS.

Four cases of new onset breast cancers were observed among the 55 cases of previvors (mean observation period: 2.5 years; incidence rate: 2.9%/Y). Among the 73 BRCA1/2 mutation positive women who underwent BCS, 3 ipsilateral breast cancer cases were observed (mean observation period: 3.5 years; incidence rate: 1.2%/Y), while 2 cases were noted among 477 cases of BRCA1/2 mutation negative cases (mean observation period: 2.2 years; incidence rate: 0.2%/Y). Of 189 BRCA1/2 mutation positive cases with unilateral breast cancer, 8 contralateral breast cancer cases were noted (mean observation period: 3.0 years; incidence rate: 1.4%/Y), while 4 cases of contralateral breast cancer were observed among 892 cases of BRCA1/2 mutation negative cases (mean observation period: 2.2 years; incidence rate: 0.2%/Y).

Fifty-one patients had undergone RRM.Six cases (11.8%) of occult breast cancer were noted in the RRM specimens, among which 2 were BRCA1 positive cases and 4 were BRCA2 positive cases. All of these six cases had undergone extensive imaging work-up prior to surgery by using mammography, ultrasound and breast MRI.

Conclusions: The incidence rate of occult cancer after risk-reducing mastectomy was reported to be about 5% in the high-risk population. Our report showed a relatively higher incidence rate of occult cancer at 11.8% among BRCA mutation positive cases, despite thorough pre-operative radiological evaluations, which included a breast MRI. These results suggest the limitations in the use of MRI for the surveillance of patients with BRCA mutations.

Citation Format: Yamauchi H, Okawa M, Yokoyama S, Nakamura S, Arai M. High incidence rate of occult cancer in risk reducing mastectomy specimens despite thorough assessment with breast MRI and ultrasound-findings from the hereditary breast and ovarian cancer registration 2016 in Japan [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD1-09.

Identification of an argpyrimidine-modified protein in human red blood cells from schizophrenic patients: A possible biomarker for diseases involving carbonyl stress

Argpyrimidine (ARP) is an advanced glycation end product thought to be generated from a reaction between methylglyoxal and arginine residues in proteins. In this study, we observed marked accumulation of an approximately 56 kD protein, reactive to anti-ARP antibodies, in the red blood cells (RBCs) of some patients with refractory schizophrenia. This ARP-modified protein was purified from the blood of schizophrenic patients and identified as selenium binding protein 1 (SBP1) by LC-MS/MS. This is the first report of ARP-modified proteins accumulating in RBCs of patients with diseases involving carbonyl stress. We also observed high accumulation of ARP-modified SBP1 in the RBCs of patients with chronic kidney disease. Therefore, this modified protein may be a novel marker of carbonyl stress.

High-resolution copy number variation analysis of schizophrenia in Japan

Recent schizophrenia (SCZ) studies have reported an increased burden of de novo copy number variants (CNVs) and identified specific high-risk CNVs, although with variable phenotype expressivity. However, the pathogenesis of SCZ has not been fully elucidated. Using array comparative genomic hybridization, we performed a high-resolution genome-wide CNV analysis on a mainly (92%) Japanese population (1699 SCZ cases and 824 controls) and identified 7066 rare CNVs, 70.0% of which were small (<100 kb). Clinically significant CNVs were significantly more frequent in cases than in controls (odds ratio=3.04, P=9.3 × 10^-9, 9.0% of cases). We confirmed a significant association of X-chromosome aneuploidies with SCZ and identified 11 de novo CNVs (e.g., MBD5 deletion) in cases. In patients with clinically significant CNVs, 41.7% had a history of congenital/developmental phenotypes, and the rate of treatment resistance was significantly higher (odds ratio=2.79, P=0.0036). We found more severe clinical manifestations in patients with two clinically significant CNVs. Gene set analysis replicated previous findings (e.g., synapse, calcium signaling) and identified novel biological pathways including oxidative stress response, genomic integrity, kinase and small GTPase signaling. Furthermore, involvement of multiple SCZ candidate genes and biological pathways in the pathogenesis of SCZ was suggested in established SCZ-associated CNV loci. Our study shows the high genetic heterogeneity of SCZ and its clinical features and raises the possibility that genomic instability is involved in its pathogenesis, which may be related to the increased burden of de novo CNVs and variable expressivity of CNVs.

[Effect of Preoperative Oral Rehydration on the Hypotension during Spinal Anesthesia.]

BACKGROUND

Preoperative dehydration is one of risk factors of hypotension during spinal anesthesia (SA). We hypothesized that preoperative oral rehy- dration (POR) may help prevent hypotension during SA.

METHODS

After obtaining approval from the ethics committee, patients who underwent surgery twice (urological surgery or orthopedic surgery) within 6 months were enrolled in the study. For the first sur- gery, the patients fasted after midnight and were given an intravenous infusion (100 ml - hr-1) on the morning before the surgery (fasting group). During the second surgery, the patients underwent POR (1,200 ml) from the night prior to the surgery to 2 hr before the surgery (POR group). The same amount of anes- thetic drug was administered during both surgeries. The delta systolic blood pressure (ASBP) was mea- sured between the pre-anesthetic condition and the early phase (0-5 min after SA induction) or secondary phase (10-15 min after SA induction). A P value<0.05 in the t-test was considered to indicate statistical sig- nificance.

RESULTS

The ASBP was lower in the POR group compared to the fasting group during both the early and secondary phases; however, only the ASBP during the early phase was significantly different (P=0.019). There was no difference in the total amount of fluid infusion, heart rate, and levels of anesthesia between both groups during the study.

CONCLUSIONS

POR prevented hypotension immedi- ately after SA induction.

Hepatitis E virus infection and acute-on-chronic liver failure in West Africa: a case-control study from The Gambia

BACKGROUND

In sub-Saharan Africa, it is unknown whether hepatitis E virus (HEV) infection is a common precipitating event of acute-on-chronic liver failure (ACLF).

AIMS

To estimate the prevalence of HEV infection in general population and assess whether HEV is a common trigger of ACLF in cirrhotic patients in The Gambia, West Africa.

METHODS

We first conducted an HEV sero-survey in healthy volunteers. We then tested cirrhotic patients with ACLF (cases) and compensated cirrhosis (controls) for anti-HEV IgG as a marker of exposure to HEV, and anti-HEV IgA and HEV RNA as a marker of recent infection. We also described the characteristics and survival of the ACLF cases and controls.

RESULTS

In the healthy volunteers (n = 204), 13.7% (95% CI: 9.6-19.2) were positive for anti-HEV IgG, and none had positive HEV viraemia. After adjusting for age and sex, the following were associated with positive anti-HEV IgG: being a Christian, a farmer, drinking water from wells, handling pigs and eating pork. In 40 cases (median age: 45 years, 72.5% male) and 71 controls (39 years, 74.6% male), ≥70% were infected with hepatitis B virus. Although hepatitis B flare and sepsis were important precipitating events of ACLF, none had marker of acute HEV. ACLF cases had high (70.0%) 28-day mortality.

CONCLUSIONS

Hepatitis E virus infection is endemic in The Gambia, where both faecal-oral route (contaminated water) and zoonotic transmission (pigs/pork meat) may be important. However, acute HEV was not a common cause of acute-on-chronic liver failure in The Gambia.

Electroencephalogram measurement from the hairy part of the scalp using polymer-based dry microneedle electrodes

This paper reports a successful electroencephalogram (EEG) measurement from the hairy part of the scalp using a polymer-based dry microneedle electrode. The electrode consists of 25 pillars, each of which has a sharp microneedle on the top. Hairs are collected into the gaps of the pillars and the microneedles can reach the scalp surface. Since the microneedles can penetrate through the stratum corneum, no conductive gel is necessary to acquire high quality EEG. We experimentally investigated the pillar diameters in EEG measurement from the occipital region with hairs. The fabricated electrodes successfully measured EEG without any skin preparation or conductive gel.

A randomized controlled trial comparing a prepackaged low-residue diet with a restricted diet for colonoscopy preparation: the impact on the results of colonoscopy in adenoma detection

AIM

This study aimed to investigate the clinical utility of a prepackaged low-residue diet (PLD) compared with a restricted diet (RD) for colonoscopic bowel preparation.

METHOD

A prospective randomized controlled trial was carried out with patients undergoing colonoscopy. One hundred patients were randomly assigned to PLD and RD groups. In the RD group, the patients received an information sheet containing acceptable low-residue options and instructions from the medical staff. All patients received 10 ml sodium picosulphate the day before colonoscopy and 1 l of polyethylene glycol with ascorbic acid (PEG-A) on the day of the colonoscopy. If the bowel preparation was not adequate, an additional PEG-A solution was given. The primary outcome was the efficacy of colonic cleansing as rated by the Boston Bowel Preparation Scale (BBPS). The additional amount of PEG-A solution, adenoma detection rate and patient tolerance were assessed as secondary outcomes.

RESULTS

The BBPS score in the PLD group was 7.3 ± 1.7 compared with 6.5 ± 1.7 in the RD group. The quality of bowel preparation was significantly better in the PLD group (P < 0.05). The mean amount of additional PEG-A solution in the PLD group was smaller than in the RD group (293.8 ± 474.8 vs 444.1 ± 625.0 ml), but there was no statistical difference between the two groups. Adenoma detection rates and patient tolerance were similar in the two groups.

CONCLUSION

Prepackaged low-residue diets PLD is superior to RD for bowel preparation for colonoscopy.

Cancer emerging from the recurrence of sessile serrated adenoma/polyp resected endoscopically 5 years ago

Since the serrated neoplastic pathway has been regarded as an important pathway of colorectal carcinogenesis, few reports have been published on clinical cases of cancer derived from sessile serrated adenoma/polyp, especially on recurrence after resected sessile serrated adenoma/polyp. An elderly woman underwent endoscopic mucosal resection of a flat elevated lesion, 30 mm in diameter, in the ascending colon; the histopathological diagnosis at that time was a hyperplastic polyp, now known as sessile serrated adenoma/polyp. Five years later, cancer due to the malignant transformation of the sessile serrated adenoma/polyp was detected at the same site. The endoscopic diagnosis was a deep invasive carcinoma with a remnant sessile serrated adenoma/polyp component. The carcinoma was surgically removed, and the pathological diagnosis was an adenocarcinoma with sessile serrated adenoma/polyp, which invaded the muscularis propria. The surgically removed lesion did not have a B-RAF mutation in either the sessile serrated adenoma/polyp or the carcinoma; moreover, the initial endoscopically resected lesion also did not have a B-RAF mutation. Immunohistochemistry confirmed negative MLH1 protein expression in only the cancer cells. Lynch syndrome was not detected on genomic examination. The lesion was considered to be a cancer derived from sessile serrated adenoma/polyp recurrence after endoscopic resection, because both the surgically and endoscopically resected lesions were detected at the same location and had similar pathological characteristics, with a serrated structure and low-grade atypia. Furthermore, both lesions had a rare diagnosis of a sessile serrated adenoma/polyp without B-RAF mutation. This report highlights the need for the follow-up colonoscopy after endoscopic resection and rethinking our resection procedures to improve treatment.

Spin-dependent acoustic response in the nonunitary A1 and A2 phases of superfluid 3He under high magnetic fields

The transverse acoustic impedance of superfluid ^{3}He was measured in the A1 and A2 phases up to 13 T to investigate the surface states in nonunitary superfluids. The temperature dependence of the impedance was much larger in the A1 phase than in the A2 phase. This nonsymmetric behavior indicates that momentum exchange with walls for spin-down surface states is quite different from that for spin-up surface states. The spin-dependent response might be a reflection of an essential feature of the nonunitary states where gap amplitudes depend on spin states. Weak-coupling theories ignore any spin-dependent processes and do not account for the nonsymmetric behavior.

Virological efficacy of combination therapy with corticosteroid and nucleoside analogue for severe acute exacerbation of chronic hepatitis B

The short-term prognosis of patients with severe acute exacerbation of chronic hepatitis B (CHB) leading to acute liver failure is extremely poor. We have reported the efficacy of corticosteroid in combination with nucleoside analogue in the early stages, but virological efficacy has not been documented. Our aim was to elucidate the virological efficacy of this approach. Thirteen patients defined as severe acute exacerbation of CHB by our uniform criteria were prospectively examined for virological responses to treatment. Nucleoside analogue and sufficient dose of corticosteroids were introduced as soon as possible after the diagnosis of severe disease. Of the 13 patients, 7 (54%) survived, 5 (38%) died and 1 (8%) received liver transplantation. The decline of HBV DNA was significant between the first 2 weeks (P = 0.02) and 4 weeks (P < 0.01). Mean reduction in HBV DNA during the first 2 weeks was 1.7 ± 0.9 log copies per mL in overall patients, 2.1 ± 0.8 in survived patients and 1.2 ± 0.9 in dead/transplanted patients. The decline of HBV DNA was significant between the first 2 weeks (P = 0.03) and 4 weeks (P = 0.02) in survived patients, but not in dead/transplanted patients. Our study shows that corticosteroid treatment in combination with nucleotide analogue has sufficient virological effect against severe acute exacerbation of CHB, and a rapid decline of HBV DNA is conspicuous in survived patients.

Elective use of surgical cricothyroidotomy for maxillofacial fracture fixation with contraindication of nasotracheal intubation: a case report

We report three cases of airway management with elective surgical cricothyroidotomy (SCT) for anesthetic management during surgical repair of maxillofacial injury involving basal skull fracture or nasal-bone fracture. In all patients, general anesthesia was induced, a supraglottic airway (SGA) device inserted, and SCT performed. Tracheal intubation was performed through SCT site, and the SGA device was removed. After surgery of maxillofacial fixation, the SGA device was re-inserted and the tracheal tube was removed. No major complications, such as subglottic stenosis or voice change, occurred. SCT holds potential as an alternative to tracheostomy because of ease of performance, fewer complications, and better cosmetic outcomes.

Electroencephalogram measurement from the hairy part of the scalp using polymer-based dry microneedle electrodes

This paper reports a successful electroencephalogram (EEG) measurement from the hairy part of the scalp using a polymer-based dry microneedle electrode. The electrode consists of 25 pillars, each of which has a sharp microneedle on the top. Hairs are collected into the gaps of the pillars and the microneedles can reach the scalp surface. Since the microneedles can penetrate through the stratum corneum, no conductive gel is necessary to acquire high quality EEG. We experimentally investigated the pillar diameters in EEG measurement from the occipital region with hairs. The fabricated electrodes successfully measured EEG without any skin preparation or conductive gel.