Collaborative Research Activities of the Arase and Van Allen Probes

This paper presents the highlights of joint observations of the inner magnetosphere by the Arase spacecraft, the Van Allen Probes spacecraft, and ground-based experiments integrated into spacecraft programs. The concurrent operation of the two missions in 2017-2019 facilitated the separation of the spatial and temporal structures of dynamic phenomena occurring in the inner magnetosphere. Because the orbital inclination angle of Arase is larger than that of Van Allen Probes, Arase collected observations at higher L -shells up to L ∼ 10 . After March 2017, similar variations in plasma and waves were detected by Van Allen Probes and Arase. We describe plasma wave observations at longitudinally separated locations in space and geomagnetically-conjugate locations in space and on the ground. The results of instrument intercalibrations between the two missions are also presented. Arase continued its normal operation after the scientific operation of Van Allen Probes completed in October 2019. The combined Van Allen Probes (2012-2019) and Arase (2017-present) observations will cover a full solar cycle. This will be the first comprehensive long-term observation of the inner magnetosphere and radiation belts.

Association between Big Five personality traits and participation in cardiac rehabilitation in Japanese patients with cardiovascular disease: a longitudinal study

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): JSPS KAKENHI

Background

Cardiac rehabilitation (CR) remains underutilised, despite its established clinical benefit. Assessments of personality traits may serve for patient-medical staff communication to promote CR implementation as they are determinants of health-related behavior. However, few studies have explored the potential effects of the Big Five personality traits on CR participation.

Purpose

This study aimed to examine the association between the Big Five personality traits and CR participation in patients with cardiovascular disease.

Methods

This longitudinal analysis included patients aged <80 years hospitalised for cardiovascular disease. We excluded patients aged ≥ 80 years because of the increased prevalence of the need of assistance for outdoor walking, resulting in non-participation in CR. The Big Five personality traits (conscientiousness, neuroticism, openness, extraversion, agreeableness) of each patient were evaluated using the Japanese version of Ten-Item Personality Inventory at discharge (references: 1, 2). Each patient was also asked to answer a self-administered questionnaire related to outpatient CR. The questionnaire included the will to participate in outpatient CR after discharge (yes or no) and the reasons for non-participation in CR. We examined the frequency of CR attendance for each patient for three months after discharge from medical records. According to the participation frequency, patients were stratified into non-participation, participation, and dropout groups. The participation group was defined as at least one CR session a month within three months after discharge. Patients who did not continue CR for three months were considered dropouts. We examined the relationship of each personality trait with non-participation in CR and dropout within three months using logistic regression analysis.

Results

A total of 139 patients hospitalised for cardiovascular disease were analysed (the mean age: 67.2 ± 9.8 years, men: 71.9%). Of 49 patients who initiated the outpatient CR after discharge, 26 patients continued CR for three months, and 23 patients dropped out. The results of the logistic regression analysis are shown in Figure 1. After adjusted for age, gender, and heart failure, high conscientiousness was associated with non-participation in CR (odds ratio [OR] 1.35, per 1 point; 95% confidence interval (CI) 1.00-1.87). The primary reason for non-participation among patients with high conscientiousness was a lack of motivation. Conversely, low conscientiousness (OR 0.56; 95% CI 0.35-0.90) and high openness (OR 2.19; 95% CI 1.27-3.78) were predictors of dropout within three months after discharge.

Conclusion

The results of this study imply that the Big Five assessment serves for the health communication to improve CR participation. In particular, high conscientious was associated with non-participation in CR due to a lack of motivation, and patients with low conscientiousness and high openness tended to dropout.

Usefulness of the japanese version of rapid dementia screening test for mild cognitive impairment in older patients with cardiovascular disease

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): JSPS KAKENHI

Background

Cognitive decline is common among older patients with cardiovascular disease and can decrease their self-management abilities. Therefore, early detection of cognitive decline is clinically important, as it can help guide effective home-based care measures, including education of family members and deployment of healthcare resources. However, the standard instruments for identifying mild cognitive impairment (MCI) are not always feasible in clinical practice.

Purpose

This study evaluated whether MCI could be detected using the Japanese version of the Rapid Dementia Screening Test (RDST-J), which is a simple screening tool for identifying cognitive decline.

Methods

This cross-sectional study included patients who were ≥ 65 years old and hospitalised because of cardiovascular disease. Patients with a pre-hospitalisation diagnosis of dementia were excluded. Each patient’s cognitive function had been measured at discharge using the RDST-J and the Japanese version of the Montreal Cognitive Assessment (MoCA-J), which is a standard tool for MCI screening. The RDST-J includes a number transcoding task and a supermarket task, and can be completed in 3 min (range: 0–12 points). The MoCA-J assesses nine domains of cognition and requires 10–15 min to complete (range: 0–30 points). The correlation between the two scores was evaluated using Spearman’s rank correlation coefficient. Receiver operating characteristic (ROC) analysis was also conducted to evaluate whether the RDST-J could identify MCI, which was defined as a MoCA-J score of ≤ 25 points.

Results

The study included 78 patients (the mean age: 77.2 ± 8.9 years, men: 56.4%). Based on a MoCA-J score of ≤ 25 points, MCI was identified in 73.1% (n = 57) of the patients. The RDST-J and MoCA-J scores were strongly correlated (r = 0.835, p <0.001). The ROC analysis revealed that an RDST-J score of ≤ 9 points provided 75.4% sensitivity and 95.2% specificity for identifying MCI, with an area under the curve of 0.899 (95% confidence interval: 0.835–0.964, Figure 1). The same cut-off value was identified when excluding patients with a high probability of dementia (RDST-J score of ≤ 4 points).

Conclusions

The RDST-J is a simple instrument and its score was highly correlated with the standard test for identifying MCI in older patients with cardiovascular disease. Our results suggest that the RDST-J may be useful for routine cognitive assessments in clinical practice. Longitudinal studies are needed to evaluate whether the RDST-J scores respond to changes in cognitive status, as well as whether this tool can be used to predict adverse health outcomes after discharge.

Association between coordination of long-term care insurance service and adverse outcome after discharge in older patients with heart failure

Funding Acknowledgements

Type of funding sources: None.

Introduction

Long-term care insurance (LTCI) has a key role in the disease management of older patients in Japan. However, clinical benefit of coordinating LTCI service during hospitalization has not been examined in patients with heart failure (HF).

Purpose

We aimed to examine the association between the coordination of LTCI service and adverse outcome after discharge in Japanese older patients with HF.

Methods

The inclusion criteria of this retrospective cohort study were patients aged ≥ 65 years hospitalised for HF who used any LTCI services after discharge. In Japan, people aged ≥ 65 who satisfy the eligibility criteria are eligible to receive LTCI services. Questionnaires regarding daily life and activities are used to assess eligibility and create the 7 certification levels: support required 1 or 2, and care levels 1 (least disabled) to 5 (most disabled). In this study, patients were divided into 1) patients without any change in LTCI service during hospitalisation (Group N), 2) patients with coordination of LTCI services during hospitalization (Group C), 3) patients who newly initiated LTCI service after discharge (Group I). The primary outcome was a composite of HF rehospitalisation and all-cause mortality. Survival rate was compared using Kaplan-Meier curve analysis and log-rank test. Multivariate analysis was conducted using Cox proportional-hazards model adjusted for propensity score calculated based on age, gender, brain natriuretic peptide, β-blocker, angiotensin converting enzyme inhibitor /angiotensin II receptor blocker, need of any walking device or assistance at discharge, living alone, LTCI level.

Results

A total of 135 older patients were included (mean age 84 years, men 46%). During the median follow-up of 580 days, 43 events occurred. The number of patients for each group was as following: Group N, n = 91; Group C, n = 20; Group I, n = 24. The survival rates were significantly different among the three groups (log-rank test p = 0.039 , Figure 1). In Cox proportional-hazards model with Group N as a reference, Group C was associated with reduced risk of the study outcome (hazard ratio 0.22, 95% confidence interval 0.05-0.91, p = 0.036). Group I also showed lower event rate but not statistically significant (hazard ratio 0.81, 95% confidence interval 0.20-0.30, p = 0.756). All the patients in Group C used visiting nurse service, whereas the implementation rates were 12.1% and 37.5% in Group N and Group I, respectively. Implementation rate of visiting rehabilitation was higher in Group C (20.0%) compared to Group N (1.1%) and Group I (4.2).

Conclusions

Patients with coordination of LTCI service during HF hospitalization showed reduced risk of adverse outcome after discharge, implying the clinical benefits of utilization of LTCI service. Further large-scale studies are needed to examine the optimal utilization of tailor-made LTCI service according to the patient’s condition.

Penetration of MeV electrons into the mesosphere accompanying pulsating aurorae

Pulsating aurorae (PsA) are caused by the intermittent precipitations of magnetospheric electrons (energies of a few keV to a few tens of keV) through wave-particle interactions, thereby depositing most of their energy at altitudes ~ 100 km. However, the maximum energy of precipitated electrons and its impacts on the atmosphere are unknown. Herein, we report unique observations by the European Incoherent Scatter (EISCAT) radar showing electron precipitations ranging from a few hundred keV to a few MeV during a PsA associated with a weak geomagnetic storm. Simultaneously, the Arase spacecraft has observed intense whistler-mode chorus waves at the conjugate location along magnetic field lines. A computer simulation based on the EISCAT observations shows immediate catalytic ozone depletion at the mesospheric altitudes. Since PsA occurs frequently, often in daily basis, and extends its impact over large MLT areas, we anticipate that the PsA possesses a significant forcing to the mesospheric ozone chemistry in high latitudes through high energy electron precipitations. Therefore, the generation of PsA results in the depletion of mesospheric ozone through high-energy electron precipitations caused by whistler-mode chorus waves, which are similar to the well-known effect due to solar energetic protons triggered by solar flares.

Oxygen torus and its coincidence with EMIC wave in the deep inner magnetosphere: Van Allen Probe B and Arase observations

We investigate the longitudinal structure of the oxygen torus in the inner magnetosphere for a specific event found on 12 September 2017, using simultaneous observations from the Van Allen Probe B and Arase satellites. It is found that Probe B observed a clear enhancement in the average plasma mass (M) up to 3-4 amu at L = 3.3-3.6 and magnetic local time (MLT) = 9.0 h. In the afternoon sector at MLT ~ 16.0 h, both Probe B and Arase found no clear enhancements in M. This result suggests that the oxygen torus does not extend over all MLT but is skewed toward the dawn. Since a similar result has been reported for another event of the oxygen torus in a previous study, a crescent-shaped torus or a pinched torus centered around dawn may be a general feature of the O+ density enhancement in the inner magnetosphere. We newly find that an electromagnetic ion cyclotron (EMIC) wave in the H+ band appeared coincidently with the oxygen torus. From the lower cutoff frequency of the EMIC wave, the ion composition of the oxygen torus is estimated to be 80.6% H+, 3.4% He+, and 16.0% O+. According to the linearized dispersion relation for EMIC waves, both He+ and O+ ions inhibit EMIC wave growth and the stabilizing effect is stronger for He+ than O+. Therefore, when the H+ fraction or M is constant, the denser O+ ions are naturally accompanied by the more tenuous He+ ions, resulting in a weaker stabilizing effect (i.e., larger growth rate). From the Probe B observations, we find that the growth rate becomes larger in the oxygen torus than in the adjacent regions in the plasma trough and the plasmasphere.

Abstract OT1-05-03: Efficacy and safety of scalp cooling device for prevention of alopecia in patients with breast cancer

Background

Chemotherapy for breast cancer causes alopecia as a side effect. Some patients refuse chemotherapy because of alopecia, resulting in the omission of a standard therapy. It is believed that a scalp cooling device can prevent alopecia by promoting vasoconstriction of the scalp and reducing exposure of the hair root cells to anticancer agents. There are phenotypic differences of the efficacy of a scalp cooling device for alopecia. In fact, a Dutch scalp cooling registry reported that the success rate of scalp cooling was 51% in European women and 33% in Asian women. Therefore, we aimed to investigate the efficacy of scalp cooling device for chemotherapy-induced alopecia among Asian women with breast cancer.

Trial design

This is a phase II trialto evaluate the efficacy and safety of scalp cooling device for risk reduction of alopecia in women with stage I/II/III breast cancer treated with adjuvant/neoadjuvant chemotherapy in a single institute.

Eligibility criteria

Women diagnosed with Stage I to III breast cancer who are scheduled to receive preoperative or postoperative adjuvant chemotherapy containing anthracycline and/or taxanes are enrolled. Patients who have blood malignancies (leukemia, non-Hodgkin lymphoma, other systemic lymphoma), and cold allergy, are excluded.

Specific aims

The primary endpoint is the proportion of patients with Common Terminology Criteria for Adverse Events (CTCAE) grade 0-1 alopecia after the completion of all cycles of chemotherapy (success rate). Secondary endpoints are safety, quality of life, use of wig or cap, and success rates after the completion of all cycles of chemotherapy distinguished by anthracycline(AC) and taxane.

The cooling device is the Paxman scalp cooling system. Scalp cooling was performed from 30 mins before initiation until 90 mins (25 min for taxane) after chemotherapy. Pictures of the scalp were taken at the time of the initiation of each course.

Statistical methods

Successful treatment was defined as the presence of less than 50% of hair-loss area. The sample size was calculated using the Simon method, with a type I error of 10% (two-sided) and a study power of 80%.The expected success rate is 30%, with a threshold success rate of 10%, and the required number of patients was estimated to be 19.

Present and target accrual

Patient accrual was started in April 2018 and present accrual is 3. We plan to enroll a total of 20 patients in the trial.

Citation Format: Kodera A, Ogura K, Hattori A, Yukawa H, Sakaguchi S, Matsuoka A, Tanaka N, Kamimura M, Jibiki N, Naritaka Y, Hirano A. Efficacy and safety of scalp cooling device for prevention of alopecia in patients with 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 OT1-05-03.

The Space Physics Environment Data Analysis System (SPEDAS)

With the advent of the Heliophysics/Geospace System Observatory (H/GSO), a complement of multi-spacecraft missions and ground-based observatories to study the space environment, data retrieval, analysis, and visualization of space physics data can be daunting. The Space Physics Environment Data Analysis System (SPEDAS), a grass-roots software development platform (www.spedas.org), is now officially supported by NASA Heliophysics as part of its data environment infrastructure. It serves more than a dozen space missions and ground observatories and can integrate the full complement of past and upcoming space physics missions with minimal resources, following clear, simple, and well-proven guidelines. Free, modular and configurable to the needs of individual missions, it works in both command-line (ideal for experienced users) and Graphical User Interface (GUI) mode (reducing the learning curve for first-time users). Both options have "crib-sheets," user-command sequences in ASCII format that can facilitate record-and-repeat actions, especially for complex operations and plotting. Crib-sheets enhance scientific interactions, as users can move rapidly and accurately from exchanges of technical information on data processing to efficient discussions regarding data interpretation and science. SPEDAS can readily query and ingest all International Solar Terrestrial Physics (ISTP)-compatible products from the Space Physics Data Facility (SPDF), enabling access to a vast collection of historic and current mission data. The planned incorporation of Heliophysics Application Programmer's Interface (HAPI) standards will facilitate data ingestion from distributed datasets that adhere to these standards. Although SPEDAS is currently Interactive Data Language (IDL)-based (and interfaces to Java-based tools such as Autoplot), efforts are under-way to expand it further to work with python (first as an interface tool and potentially even receiving an under-the-hood replacement). We review the SPEDAS development history, goals, and current implementation. We explain its "modes of use" with examples geared for users and outline its technical implementation and requirements with software developers in mind. We also describe SPEDAS personnel and software management, interfaces with other organizations, resources and support structure available to the community, and future development plans.

ELECTRONIC SUPPLEMENTARY MATERIAL

The online version of this article (10.1007/s11214-018-0576-4) contains supplementary material, which is available to authorized users.

Pulsating aurora from electron scattering by chorus waves

Auroral substorms, dynamic phenomena that occur in the upper atmosphere at night, are caused by global reconfiguration of the magnetosphere, which releases stored solar wind energy. These storms are characterized by auroral brightening from dusk to midnight, followed by violent motions of distinct auroral arcs that suddenly break up, and the subsequent emergence of diffuse, pulsating auroral patches at dawn. Pulsating aurorae, which are quasiperiodic, blinking patches of light tens to hundreds of kilometres across, appear at altitudes of about 100 kilometres in the high-latitude regions of both hemispheres, and multiple patches often cover the entire sky. This auroral pulsation, with periods of several to tens of seconds, is generated by the intermittent precipitation of energetic electrons (several to tens of kiloelectronvolts) arriving from the magnetosphere and colliding with the atoms and molecules of the upper atmosphere. A possible cause of this precipitation is the interaction between magnetospheric electrons and electromagnetic waves called whistler-mode chorus waves. However, no direct observational evidence of this interaction has been obtained so far. Here we report that energetic electrons are scattered by chorus waves, resulting in their precipitation. Our observations were made in March 2017 with a magnetospheric spacecraft equipped with a high-angular-resolution electron sensor and electromagnetic field instruments. The measured quasiperiodic precipitating electron flux was sufficiently intense to generate a pulsating aurora, which was indeed simultaneously observed by a ground auroral imager.

Der f 35: An MD-2-like house dust mite allergen that cross-reacts with Der f 2 and Pso o 2

BACKGROUND

Dermatophagoides farinae is a source of airborne house dust mite (HDM) allergens. We elucidated IgE-reactive allergens from D. farinae by two-dimensional immunoblotting-based allergenome analysis, and identified one new allergen, named Der f 35, that possesses IgE-binding capacity comparable to that of Der f 2. The aim of this study was to clarify the allergenic capacity of new HDM allergen Der f 35.

METHODS

We cloned der f 35 from D. farinae mRNA and produced recombinant Der f 35 in Escherichia coli. The IgE-binding capacity of Der f 35 and its cross-reactivity with group 2 allergens from D. farinae and Psoroptes ovis were determined by enzyme-linked immunosorbent assay (ELISA) and ELISA inhibition assays, respectively.

RESULTS

The deduced amino acid sequence for der f 35, which possesses the MD-2-related lipid-recognition domain, showed higher identity with group 2 allergens from P. ovis (61.5%) and Blomia tropicalis (50.7%) than with Der f 2 (40.8%). Der f 35 showed IgE-binding frequencies of 77.5% (31/40) for the native form upon allergenome analysis and 51.4% (18/35) for recombinant structure by ELISA. Der f 35 showed cross-reactivity with Der f 2 and Pso o 2 in reaction with HDM-allergic patients' IgE by ELISA inhibition assay.

CONCLUSION

Der f 35 is a candidate major allergen from D. farinae, which is more similar to group 2 allergens from sheep scab mite and storage mites. Der f 35 could be responsible for the cross-reactivity among group 2 mite allergens.

Abstract OT1-01-03: A phase II trial of neoadjuvant epirubicin/cyclophosphamide followed by weekly nanoparticle albumin-bound paclitaxel with trastuzumab for HER2-positive breast cancer

Background

Paclitaxel (PTX) is a standard treatment for metastatic breast cancer (MBC) and it is often used as adjuvant and neoadjuvant chemotherapy for patients with early-stage disease. Nanoparticle albumin-bound (Nab)-PTX was also effective in patients with metastatic and early-stage. A comparison of weekly and triweekly nab-PTX regimens suggested that weekly nab-PTX resulted in superior progression-free survival. However, the optimal dose and schedule of weekly nab-PTX have not been determined. The efficacy and tolerability of epirubicin/cyclophosphamide (EC) followed by weekly nab-PTX (125 mg/m2) ± trastuzumab in node-positive breast cancer was determined in our previous trial. A high pathologic complete response (pCR) rate was obtained in HER2-positive patients. However, because nab-PTX administration was frequently postponed and discontinued, the optimal dose needs to be determined. In the previous trial, the median relative dose intensity of nab-PTX was 80% among patients with pCR. Therefore the dose of nab-PTX was reduced by 20% in this newly designed trial.

Trial design

This phase II trial aimed to evaluate the efficacy and toxicity of neoadjuvant EC followed by weekly nab-PTX with trastuzumab in patients with HER2-positive breast cancer. Patients will receive 4 cycles of epirubicin (90 mg/m2) and cyclophosphamide (600 mg/m2) every 3 weeks, followed by 4 cycles of nab-PTX (100 mg/m2) on days 1, 8, and 15, over a 28-day cycle. Fifteen cycles of trastuzumab (2 mg/kg, loading dose: 4 mg/kg) will be added to the nab-PTX regimen.

Eligibility criteria

Surgery and chemotherapy-naïve patients with pathologically confirmed T2-4 N0-3 invasive breast cancer, as diagnosed by core needle biopsy, are included. Eligibility criteria include age 20–70 years, a performance status of 0–2, and adequate organ function.

Specific aims

The primary endpoint is the pCR rate in the breast and axilla. Secondary endpoints include the breast conservation rate, toxicities, relative dose intensities, feasibility, and overall survival. A pCR is defined as the disappearance of invasive cancer cells, including in the axilla; residual intraductal cancer is acceptable.

Statistical methods

The sample size was calculated using the Simon method, with a type I error of 5% and a study power of 80%. The expected rate of pCR is 72% with a threshold pCR rate of 45%. The required number of patients was estimated to be 25.

Present and target accrual

Patient accrual within two medical centers began in May 2014. A final study population of 30 patients is expected (Trial registration: UMIN000013886).

Citation Format: Kodera A, Hirano A, Inoue H, Ogura K, Hattori A, Sakaguchi S, Yukawa H, Matsuoka A, Tanaka N, Kamimura M, Jibiki N, Fujibayasi M, Naritaka Y, Shimizu T. A phase II trial of neoadjuvant epirubicin/cyclophosphamide followed by weekly nanoparticle albumin-bound paclitaxel with trastuzumab for HER2-positive breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT1-01-03.

Abstract P3-13-13: Breast-conserving surgery plus hormone therapy without irradiation in elderly women with early breast cancer

Background

The meta-analysis of the Early Breast Cancer Trialists' Collaborative Group (EBCTCG) revealed that whole-breast irradiation after breast conserving surgery (BCS) decreased ipsilateral breast tumor recurrence (IBTR) and breast cancer-related death. However, elderly patients can find daily hospital attendance difficult, and their IBTR risk is low. A randomized control trial was performed in women aged ≥70 years with hormone-positive breast cancer to investigate the usefulness of breast-conserving therapy without irradiation (Hughes et al. N Engl J Med 2004). Since September 2001, we have offered BCS plus hormone therapy without irradiation in patients who satisfy the following criteria: age ≥60 years; pathologically node negative, hormone-positive breast cancer; a negative surgical margin; and no lymphovascular invasion. We assessed prognosis in patients who chose this option.

Patients and methods

Between September 2001 and December 2014, 219 patients met the inclusion criteria; 90 and 129 patients underwent BCS plus hormone therapy with or without irradiation, respectively. The cumulative IBTR incidence and overall survival (OS) for the groups was evaluated. A negative surgical margin was defined as a margin of ≥5 mm.

Results

The median ages at operation were 73 years (range, 60–88 years) and 65 years (range, 60–80 years) for the without and with irradiation groups, respectively (p <0.001). There were no significant differences in tumor size, lymph node metastasis, or adjuvant therapy between the groups. The median follow-up duration is presently 4.6 years. IBTR was observed in 5 (3.9%) and 1 (1.1%) patient(s) in the without and with irradiation groups, respectively (p = 0.192). The 5-year IBTR cumulative incidences were 0.9% and 2.2%, and the 10-year were 6.7% and 2.2%, for the without and with irradiation groups, respectively (p = 0.390). The 5-year OS rates were 93.8% and 98.5%, and the 10-year OS rates were 89.7% and 94.0 for the without and with irradiation groups, respectively (p = 0.205).

Conclusion

BCS plus hormone therapy without irradiation in elderly patients is an appropriate option.

Citation Format: Inoue H, Hirano A, Ogura K, Hattori A, Yukawa H, Sakaguchi S, Matsuoka A, Tanaka N, Kodera A, Kamimura M, Fujibayashi M, Naritaka Y, Shimizu T. Breast-conserving surgery plus hormone therapy without irradiation in elderly women with early breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-13-13.

A surgical navigation system for aortic vascular surgery: a practical approach

In aortic vascular surgery, a navigation system must represent the anatomical map of individual patient in order to detect the important artery. To provide a proper fit for positions along the dorsoventral axis, the spinous process was added to a currently used anatomical point set consisting of four anterior body landmarks. In addition, we attempted to reduce the registration error by compensating for alignment errors resulting from variations in tissue thickness at each landmark. The alignment values were examined using a human phantom consisting of a skeleton model with subcutaneous tissue in the semilateral position. Using this method, a phantom simulation and five clinical trials were performed. Target errors were evaluated at the orifice of the intercostal artery. In the phantom simulation, the error at the target point was 4.1 ± 2.7 mm. However, for one patient undergoing thoracoabdominal aortic aneurysm replacement surgery, the target error was 8.0 mm using the proposed method.

Primary aldosteronism associated with subclinical Cushing syndrome

BACKGROUND

Recently, it has been reported that the incidence of primary aldosteronism (PA) among patients with hypertension is much more frequent than previously reported.

AIM

In the present study, we investigated the frequency and features of PA associated with subclinical Cushing syndrome (SCS).

MATERIAL AND METHODS

Subjects included consecutive patients (no.=39) who were diagnosed as PA and performed adrenal venous sampling between 2003 and 2011 in our institute.

RESULTS

In 39 subjects who were diagnosed as PA, 29 patients were operated and 5 cases (12.8%) showed no suppression in low-dose dexamethasone suppression test. Four cases of them were demonstrated to be associated with SCS, and one was associated with overt Cushing syndrome (CS). Post-operatively, 3 cases received replacement therapy of hydrocortisone, while others did not. Pathological findings indicated the diagnosis of aldosterone-producing adenoma in 4 cases associated with SCS, and of idiopathic hyperaldosteronismin in one case associated with overt CS. In all 5 cases, immunohistochemical analysis demonstrated the immunoreactivities of both 3βHSD and P450c17 in the adrenocortical tumors, the marked cortical atrophy in the zona fasciculata and reticularis, the decreased dehydroepiandrosterone sulfotransferase expression, and suppression of hypothalamo- pituitary-adrenal axis indicating the autonomous secretion of cortisol from the tumor.

CONCLUSIONS

The present study suggests that PA is frequently associated with SCS with prevalence of more than 10%, justifying the routine examinations for SCS in PA cases.

[Submuscular Nuss procedure using mammary areola incision for adult pectus excavatum with significant upper chest depression]

Submuscular Nuss procedure using mammary areola incision was performed on adult pectus excavatum. The skin was incised approximately 3 cm (almost half the entire areolar circumference). The subcutaneous tissue and pectoralis major muscle were incised to reach the 4th rib. The pectoralis major muscle and serratus anterior muscle were separated from the costae and intercostal muscle. A part of the 3rd intercostal muscle was removed. The sternum and cartilages were robust; therefore the anterior chest wall was elevated with a jack allowing Nuss procedure. After fixing a bar, a drainage tubes were placed beneath the bilateral pleural cavity and muscular layer. Then, the pectoralis major muscle was sutured and the subcutaneous tissue was closed with 2 layers of suturing. The skin was closed with 6-0 nylon sutures, leaving no obvious scar. The mammary areola incision which is used for breast cancer can also successfully applied to Nuss procedure. The Nuss procedure using mammary areola incision is recommended for pectus excavatum with upper chest depression.

A pilot study of evaluation of the antioxidative activity of resveratrol and its analogue in a 6-month feeding test in young adult mice

Resveratrol, a polyphenolic phytoalexin, has free-radical scavenging activity and we found that it induces chromosomal aberrations, micronuclei, and sister chromatid exchanges in vitro. We synthesized its analogue 4-hydroxy-trans-stilbene (4-OH) and found that it has the same in vitro clastogenic activities as resveratrol, suggesting that the 4' hydroxy group of resveratrol is responsible for the effect. We fed resveratrol and 4-OH to young adult ICR mice at 0, 0.2, 2, or 20 ppm in their standard powder diet for 6 months and investigated the antioxidative effects. Half of each group was given 3000 ppm potassium bromate (KBrO(3)) in water for the last week to cause oxidative damage. Body weight gain tended to increase in males at 0.2 ppm resveratrol or 4-OH, and in females at 2 ppm 4-OH. Micronucleus (MN) analysis in bone marrow erythrocytes showed that the KBrO(3) tendency to induce MN was not prevented by the dietary resveratrol or 4-OH, which themselves did not induce MN under the present conditions. In this pilot study, resveratrol and 4-OH showed no obvious effect, either beneficial or adverse, at doses that are feasible in daily life for humans.

Resveratrol, a naturally occurring polyphenol, induces sister chromatid exchanges in a Chinese hamster lung (CHL) cell line

We tested the genotoxicity of 3,5,4'-trihydroxystilbene (resveratrol), a polyphenolic phytoalexin found in grapes, in a bacterial reverse mutation assay, in vitro chromosome aberration (CA) test, in vitro micronucleus (MN) test, and sister chromatid exchange (SCE) test. Resveratrol was negative in the strains we used in the bacterial reverse mutation assay (S. typhimurium TA98 and TA100 and E. coli WP2uvrA) in the absence and presence of a microsomal metabolizing system. It induced structural CAs at 2.5-20 microg/ml and showed weak aneuploidy induction in a Chinese hamster lung (CHL) cell line. It induced MN cells and polynuclear and karyorrhectic cells after 48h treatments in the in vitro MN test. In the SCE test, resveratrol caused a clear cell-cycle delay; at 10 microg/ml, the cell cycle took twice as long as it did in the control. Resveratrol induced SCEs dose-dependently at up to 10 microg/ml, at which it increased SCE six-fold, and the number was almost as large as mitomycin C, a strong SCE inducer. No second mitoses were observed at 20 microg/ml even after 54h. Cell cycle analysis by FACScan indicated that resveratrol caused S phase arrest, and 48h treatment induced apoptosis. Our results suggest that resveratrol may preferentially induce SCE but not CA, that is, it may cause S phase arrest only when SCEs are induced.

Chromosomal effects of newly identified water pollutants PBTA-1 and PBTA-2 and their possible mother compounds (azo dyes) and intermediates (non-ClPBTAs) in two Chinese hamster cell lines

We performed the in vitro micronucleus (MN) test on 2-[2-(acetylamino)-4-[bis(2-methoxyethyl)amino]-5-methoxyphenyl]-5-amino-7-bromo-4-chloro-2H-benzotriazole (PBTA-1) and 2-[2-(acetylamino)-4-[N-(2-cyanoethyl)-ethylamino]-5-methoxyphenyl]-5-amino-7-bromo-4-chloro-2H-benzotriazole (PBTA-2), which are newly identified water pollutants from the Nishitakase river in Kyoto, Japan, and on their possible mother compounds (AZO DYE) and intermediates (non-ClPBTAs). We tested these compounds in the absence and presence of S9 mix in two Chinese hamster cell lines CHL and V79-MZ and scored MN, polynuclear and karyorrhectic (PN), and mitotic (M) cells. PBTA-2 in the absence of S9 mix induced the strongest responses in both cell lines. It was also a strong inducer of binucleate cells in PN cells in both cell lines, which suggested that it induced polyploidy. PBTA-1 showed clear positive results only in the absence of S9 mix and only in V79-MZ cells, inducing aneuploidy. In CHL cells AZO DYE-1 significantly induced MN cells in the presence of S9 mix, and AZO DYE-2 induced MN and PN cells, including binucleate cells and cells with a multilobed nucleus, in the absence of S9 mix. In V79-MZ cells, AZO DYE-1 and -2 induced primarily M cells in the presence of S9 mix. 9% of the M cells treated with 50 microg/ml AZO DYE-1 showed endoreduplication. AZO DYE-2 at 200 microg/ml condensed the chromatin in 100% of the cells. The non-ClPBTAs were a bit more cytotoxic than the other compounds and induced a slight increase in MN cells in both cell lines. Some of the chemicals tested induced a characteristic karyomorphology that might reflect abnormal cell division. Abnormalities of cell division could be detected in PN and M cells as well as in MN cells. Structure-activity relationships have also been discussed.

Light conditions during sleep period and sleep-related lifestyle in Japanese students

The effects of light conditions during night sleep on sleep habits and morning-evening preference were studied in Japanese students (18-28 years old). Students who usually used fluorescent or non-fluorescent light on the room ceiling, wall or desk preferred to have a daytime nap significantly later (Mean: 14:50 h) than those who used no light (13:34 h). Students who used no curtain or a half-transparent lace-curtain showed shorter sleep latency (duration from going-to-bed to sleep-onset) than those who used a curtain which shuts off lights from outside. Light conditions during the middle of night and early in the morning may affect the timing of sleep in Japanese students based on the circadian system.

Transitions of macroscopic structures and self-induced chaos observed in plasmas by a dc hollow cathode discharge having features of nonlinear open systems

A novel experimental investigation is presented on the connection between discontinuous transitions of macroscopic structures of plasma and self-induced chaotic oscillations characterized by the positive Lyapunov exponents lambda(L) through the period-doubling route in a dc hollow cathode discharge, which has features of nonlinear open systems. We have clarified experimentally that there appear different discharge modes accompanying the discontinuous transitions, and detailed qualitative explanations are presented about the mechanism of those transitions. It is shown that fundamental frequencies of the self-induced periodic oscillations with nonpositive lambda(L) change with the changes of discharge current, and the amplitude of chaotic oscillations with the positive lambda(L) jumps up almost one order higher than that of nonchaotic ones with the nonpositive lambda(L). The self-induced chaotic oscillations with the positive lambda(L) have been observed near two edges of discontinuous transitions of plasma structures, suggesting that the chaotic mode is associated with the discontinuous transition of macroscopic structures in some nonlinear open systems.

A primitive myoglobin from Tetrahymena pyriformis: its heme environment, autoxidizability, and genomic DNA structure

A myoglobin-like protein isolated from Tetrahymena pyriformis is composed of 121 amino acid residues. This is much smaller than sperm whale myoglobin by 32 residues, suggesting a distinct origin from the common globin gene. We have therefore examined this unique protein for its structural, spectral and stability properties. As a result, the rate of autoxidation of Tetrahymena oxymyoglobin (MbO(2)) was found to be almost comparable to that of sperm whale MbO(2) over a wide range of pH 4-12 in 0.1 M buffer at 25 degrees C. Moreover, both pH profiles exhibited the remarkable proton-assisted process, which can be performed in sperm whale myoglobin by the distal (E7) histidine as its catalytic residue. These kinetic observations are also in full accord with spectral examinations for the presence of a distal histidine in ciliated protozoa myoglobin. At the same time, we have isolated the globin genes both from T. pyriformis and Tetrahymena thermophila, and found that there is no intron in their genomic structures. This is in sharp contrast to previous reports on the homologous globin genes from Paramecium caudatum and Chlamydomonas eugametos. Rather, the Tetrahymena genes seemed to be related to the cyanobacterial globin gene from Nostoc commune. These contracted or truncated globins thus have a marked diversity in the cDNA, protein, and genomic structures.

Dual nature of the distal histidine residue in the autoxidation reaction of myoglobin and hemoglobin comparison of the H64 mutants

The oxygenated form of myoglobin or hemoglobin is oxidized easily to the ferric met-form with generation of the superoxide anion. To make clear the possible role(s) of the distal histidine (H64) residue in the reaction, we have carried out detailed pH-dependence studies of the autoxidation rate, using some typical H64 mutants of sperm whale myoglobin, over the wide range of pH 5-12 in 0.1 M buffer at 25 degrees C. Each mutation caused a dramatic increase in the autoxidation rate with the trend H64V >/= H64G >/= H64L >> H64Q > H64 (wild-type) at pH 7.0, whereas each mutant protein showed a characteristic pH-profile which is essentially different from that of the wild-type or native sperm whale MbO2. In particular, all the mutants have lost the acid-catalyzed process that can play a dominant role in the autoxidation reaction of most mammalian myoglobins or hemoglobins. Kinetic analyses of various types of pH-profiles lead us to conclude that the distal histidine residue can play a dual role in the nucleophilic displacement of O2- from MbO2 or HbO2 in protic, aqueous solution. One is in a proton-relay mechanism via its imidazole ring, and the other is in the maximum protection of the FeO2 center against a water molecule or an hydroxyl ion that can enter the heme pocket from the surrounding solvent.

The 2-phenylbenzotriazole-type water pollutant PBTA-2 has cytochalasin B-mimetic activity

The 2-phenylbenzotriazole (PBTA)-type water pollutant, 2-[2-(acetylamino)-4-[N-(2-cyanoethyl)ethylamino]-5-methoxyphenyl]-5- amino-7-bromo-4-chloro-2H-benzotriazole (PBTA-2), has been recently identified in samples from the Nishitakase River in Kyoto, Japan, and shows potent mutagenic activities in Salmonella typhimurium in the presence of a microsomal metabolizing system (S9 mix). In the present study, we conducted the in vitro micronucleus (MN) test on PBTA-2 in the absence and presence of S9 mix in two Chinese hamster cell lines, CHL and V79-MZ. In the MN test, PBTA-2 was weakly positive in CHL cells and strongly positive in V79-MZ cells. Because the positive results were accompanied by a statistically significant increase in the number of polynuclear (PN) and/or mitotic (M) cells, we examined treated cells in metaphase to see if numerical chromosome aberrations were being induced. We found that PBTA-2 induces polyploidy in both CHL and V79-MZ cells. A detailed analysis of MN preparations showed that in CHL cells, PBTA-2 predominantly induces equal-sized binucleated cells. Rhodamine phalloidin staining revealed that PBTA-2 causes actin filament abnormalities in both cell lines similar to those caused by cytochalasin B. Cytochalasin B induced PN cells predominantly and dose dependently, and almost all the cells were equal-sized and binucleate. The results suggest that PBTA-2 has cytochalasin B-mimetic activity, although agents affecting actin filaments, such as cytochalasins, phallotoxins and chloropeptide, have been derived only from molds so far. This study also suggests that our MN test protocol may be used to identify chemicals that have cytochalasin B-mimetic activity as well as those that induce numerical aberrations.

Semi-quantitative evaluation of genotoxic activity of chemical substances and evidence for a biological threshold of genotoxic activity

In Japan, the Chemical Substances Control Law requires evaluation of the genotoxic potential of chemical substances semi-quantitatively by application of a ranking system. During the past 10 years under the law, 1049 new chemical substances were evaluated by a reverse mutation assay in bacteria (RMA) and a chromosome aberration test in cultured mammalian cells (CAT). Of them, 130 (12.4%) were positive in the RMA and 402 (38.3%) were positive in the CAT. Eighty (7.6%) were positive in both tests. Fifty (4.8%) were positive only in the RMA, 322 (30.7%) were positive only in the CAT, and 452 (43.1%) were positive in either the RMA or the CAT. Thus, the tests complement each other in detecting genotoxic substances in vitro. To explore the "threshold" concept, we compared the genotoxic responses of Salmonella typhimurium tester strains with and without DNA repair capacity. Recently constructed strains of TA1535 lacking O(6)-methylguanine DNA methyltransferase genes (ogt(ST) or ada(ST) and ogt(ST)) showed dose-related increases in the number of revertants induced by N-ethyl-N'-nitro-N-nitrosoguanidine, methyl methanesulfonate, dimethylnitrosamine, and ethylnitrosourea, while in the same dose ranges the parental strain TA1535 did not. This finding suggests that there is a threshold at which all DNA damage induced by low dose levels of genotoxic chemicals are repaired. That biological threshold seems to exist for both DNA and non-DNA targeting chemicals.

Validation study of the in vitro micronucleus test in a Chinese hamster lung cell line (CHL/IU)

We conducted a collaborative validation study, under the auspices of the Japanese Ministry of Labour, on the in vitro micronucleus test to see if it could be used as an alternative to the in vitro chromosome aberration test for evaluation of chemical safety. We used the Chinese hamster lung cell line (CHL/IU), which is the most widely used system for the latter test in Japan, and evaluated 66 chemicals, including clastogens and polyploidy inducers. The cytochalasin B cytokinesis blocking method, which is commonly used in human lymphocyte culture, was applied to the established cell line, but did not improve the detection of chemically-induced micronuclei in continuously growing cells. The highest micronucleus frequencies were obtained at 48 or 72 h continuous treatments. In short treatments (6 h), a 42 h recovery time yielded the best responses. Concordance between the results of the micronucleus test and the chromosomal aberration test was satisfactorily high (88.7%), and we concluded that the in vitro micronucleus test could be used in place of the chromosomal aberration test as a simple and rapid method for detecting clastogens and aneugens in vitro. We also propose a protocol for the test.

A proposal for a simple way to distinguish aneugens from clastogens in the in vitro micronucleus test

In our previous in vitro micronucleus (MN) study, we showed that aneugens, in addition to inducing micronuclei, induce a higher frequency of polynuclear (PN) and mitotic (M) cells than clastogens. We hypothesized that the frequency of PN and M cells induced can distinguish aneugens from clastogens. To test the hypothesis, we conducted the micronucleus tests with mitomycin C (MMC), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), vincristine (VINC) and diazepam in a Chinese hamster cell line (CHL) and VINC, benzo[a]pyrene (BP) and 7,12-dimethylbenz[a]anthracene (DMBA) in a subclone of V79 cells (V79-MZ). All chemicals increased the frequency of M cells with statistical significance. All chemicals except diazepam increased the frequency of PN cells with statistical significance. Three of the aneugens (VINC, BP and DMBA) induced >/=200 PN cells/1000 cells while the clastogens (MNNG and MMC) induced 100 PN cells at most. All the aneugens but no clastogens significantly increased the frequency of M cells. We propose that micronucleus test-positive chemicals that induce >/=200 PN cells/1000 cells and significantly increase the frequency of M cells are aneugens and those that induce at most 100 PN cells/1000 cells and do not significantly increase the frequency of M cells in our MN test protocol are clastogens. Diazepam, however, did not induce PN cells, although it increased the frequency of M cells dose dependently. We explain this fact in relation to diazepam's mode of action. Our proposal suggests a quick, easy and practical way to distinguish aneugens from clastogens for screening purposes.

W-5 and quin 2-AM reverse the inhibitory effect of insulin on lipolysis due to dibutyryl cAMP

The effects of W-5, a weak calmodulin antagonist, and quin 2-AM, a cell permeant calcium chelator, on lipolysis and antilipolytic activity of insulin were studied in isolated rat adipocytes. We have previously shown that W-7, a strong calmodulin antagonist, suppresses the inhibitory effect of insulin on lipolysis due to dibutyryl cAMP (Bt2cAMP) in a dose-dependent manner [H. Goko, A. Matsuoka, Diabetes Res. Clin. Prac. 19 (1993) 177-181] and verapamil, a calcium antagonist, potentiates lipolysis due to Bt2cAMP. Like W-7, W-5 suppressed the antilipolytic action of insulin on lipolysis due to Bt2cAMP in a dose-dependent manner. However, when lipolysis was potentiated with 3-isobutyryl-1-methylxanthine (IBMX), W-5 did not suppress the antilipolytic action of insulin. At the same time, like verapamil, W-5 also potentiated lipolysis due to Bt2cAMP in a dose-dependent manner. Thus W-5 has the pharmaceutical effects of both W-7 and verapamil. The chelation of intracellular Ca2+ in adipocytes with quin 2-AM also produced a dose-dependent potentiation of lipolysis due to Bt2cAMP and suppression of the antilipolytic action of insulin on lipolysis due to Bt2cAMP. These effects of quin 2-AM are the same as those of W-5. Therefore, our results suggest that the cytoplasmic Ca2+ plays a pivotal role in mediating the potentiation of lipolysis and antilipolytic action of insulin when lipolysis is induced by Bt2cAMP in rat adipocytes and that W-5 appears to exert its pharmaceutical effects through the inhibition of intracellular calcium-dependent steps other than calmodulin.

[Long-term immunological study on postoperative adjuvant treatment with interferon-gamma in patients with renal cell carcinoma who underwent nephrectomy]

Previously, we reported the short-term immunological effects of postoperative adjuvant interferon-gamma (IFN-gamma) administration to renal cell carcinoma patients as determined by three-color flow cytometry. We now report the results of a long-term study on a larger number of subjects. Thirty-three patients with renal cell carcinoma received a prophylactic intramuscular injection of IFN-gamma (300 x 10(4) units per week) after nephrectomy. We evaluated immunological changes by measuring peripheral blood lymphocyte subsets including activated cytotoxic T lymphocytes (ACTL), cytotoxic T lymphocytes (CTL), activated suppressor T lymphocytes (ASTL), helper T lymphocytes (HTL), activated suppressor-inducer T lymphocytes (AITL), and suppressor-inducer T lymphocytes (SITL). We also estimated the natural killer (NK) activity by a cytolytic test. All 33 patients were examined for at least 12 months after the start of IFN-gamma injection, and 18 patients were examined for 30 months including the 6-month period following discontinuation of IFN-gamma injection. We found significant enhancement of the ACTL subset from the second week to the sixth month after the start of IFN-gamma injection. On the other hand, we found a significant decrease in the percentage of the HTL and SITL subsets for a long time after the start of injection. NK activity significantly increased throughout the period of administration, and it continued to increase for six months after discontinuation of IFN-gamma injection.

Clinical usefulness of serum tartrate-resistant fluoride-sensitive acid phosphatase activity in evaluating bone turnover

This study was carried out to evaluate the clinical validity and usefulness of serum tartrate-resistant fluoride-sensitive acid phosphatase (TrFsACP) activity using 2,6-dichloro-4-acetylphenyl phosphate as substrate at pH 6.2 in metabolic bone diseases. The mean Z-scores of TrFsACP activity in patients on hemodialysis were higher than in healthy subjects (male: 2.04+/-1.98, n = 49, P < .05; female: 1.49+/-2.43, n = 39, P < .05) and increased with duration of hemodialysis (r = .516, P < .01). Bone alkaline phosphatase also was found to be significantly higher in hemodialysis patients (male: 0.93+/-1.49, P < .05; female: 1.66+/-2.42, P < .05) compared with normal subjects: but had lower correlation with duration of hemodialysis than TrFsACP (r = .277, P < .05). Ulcerative colitis (1.37+/-2.21, n = 15) in males showed a significantly higher Z-score of TrFsACP compared with control subjects (P < .05). The relationship of TrFsACP activity and ultrasound findings (stiffness; speed of sound [SOS]; broadband ultra sound attenuation [BUA]) in healthy women aged 30-75 years (n = 95) were inversely and significantly correlated with stiffness (r = -.465, P < .01 ), SOS (r = -.484, P < .01), and BUA (r = -.366, P < .01), but were age dependent. TrFsACP activity significantly correlated with stiffness (r = -.521, P < .05) and SOS (r = -.527, P < .05) only in the age group of 46-55 years. BUA (r = -.313, P > .05) did not correlate significantly in any subject in the present study. We conclude that serum TrFsACP activity is useful in the diagnosis and monitoring of bone turnover.

Toxoplasma antibody prevalence in Nepalese pregnant women and women with bad obstetric history

Sera from randomly selected 345 pregnant Nepalese women aged 16-36 years and 13 women with bad obstetric history (BOH) were tested for the presence of Toxoplasma antibodies using microlatex agglutination (MLA) and ELISA methods. The overall prevalence was 55.4% (191/345). Prevalence was slightly higher (59.0%) in older age-group (27-36 years) compared with younger age-group (16-26 years) (52.2%). No significant difference in antibody prevalence in women belonging to two different ethnic-groups (Tibeto-Burmans 57.8%, Indo-Aryans 52.7%) was observed (p>0.05). MLA antibody titer ranged from 1:16 to 1:2,048. Over three-fourth of the women showed either high (1:510 or over) or low (1:16 or 1:32) antibody titer. Three percent (6/191) of MLA antibody positive subjects had Toxoplasma IgM antibodies by IgM-ELISA. All six IgM antibody positive pregnant women had MLA antibody titer of over 1:510. Of the total 13 women with BOH, 5 (38.5%) had Toxoplasma antibodies of which 2 (40.0%) were positive for Toxoplasma-IgM antibodies.

Spindle disturbances induced by benzo[a]pyrene and 7, 12-dimethylbenz[a]anthracene in a Chinese hamster cell line (V79-MZ) and the stability of the numerical chromosome aberrations that follow

We previously reported that benzo[a]pyrene (BP) and 7, 12-dimethylbenz[a]anthracene (DMBA) induce aneuploidy and polyploidy, respectively, in the Chinese hamster cell line V79-MZ in the absence of S9 mix. In the present study we investigated the effect of BP and DMBA on the mitotic spindle. BP caused incomplete spindle formation and DMBA inhibited spindle formation completely. The combined results indicate that incomplete spindles caused by BP resulted in aneuploidy, and the absence of spindle formation caused by DMBA resulted in polyploidy. The induced polyploidy was stable for several serial passages in fresh medium. BP and DMBA induced different chromosome number distributions. After BP treatment, the normal distribution of chromosome number was restored in 4 days. After DMBA treatment, on the other hand, a tetraploid peak was maintained for 2 months following an initial transient broad distribution of chromosome number after 1 day. The results suggest that different mechanisms were involved in the induction of numerical aberrations by BP and DMBA. Furthermore the induction of numerical aberrations by BP and DMBA was reproducible over 5 months of passages. In four clones tested, the frequency of cells with the modal chromosome number in control cultures gradually decreased from 82% on the average just after cloning to 62% 5 months later. BP and DMBA induced characteristic ploidy changes following succeeding cell passages for up to 5 months, indicating that the ability to respond to BP and DMBA was stable for that period of time. Because these findings were specific to V79-MZ cells, this cell line might be a good tool for studying chemicals that induce numerical chromosome aberrations.

[Appearance of ovomucoid in coagulated egg yolk passing through from soluble fraction of coagulated egg white in boiled egg]

Ovomucoid is a egg white protein which has a strong allergenicity with a unique characteristic in heat-noncoagulable one contrast to heat-coagulable other major egg white proteins. By ELISA and immunoblots analysis, ovomucoid was detected in heat-coagulated egg yolk after immediate boiling of hen's egg for 15 min (boiled egg) at the concentration of 4.8 +/- 0.8 micrograms/g egg yolk, but not detected in raw egg yolk collected by insertion of a needle into the egg yolk cavity. Ovomucoid in heat-coagulated egg yolk was increased by standing the boiled eggs at room temperature for 10, 30, 60 and 120 min at the concentration of 7.5 +/- 3.4, 17.2 +/- 15.1, 28.1 +/- 5.9 and 78.8 +/- 31.3 micrograms/g egg yolk, respectively. The soluble fraction prepared from heat-coagulated egg white of boiled egg contained 37.7 +/- 3.2 mg/ml of proteins including 14.2 +/- 11.9 mg/ml of ovomucoid as a major and miners of detectable ovalbumin and ovotransfferin. These results suggested that the appearance of ovomucoid in coagulated egg yolk of boiled egg was due to passing the soluble fraction rich in ovomucoid in heat-coagulated egg white through into the coagulated egg yolk, which may have notable consequences for the present of ovomucoid as a major egg white allergen in yolk egg of boiled egg.

African elephant myoglobin with an unusual autoxidation behavior: comparison with the H64Q mutant of sperm whale myoglobin

Elephant myoglobins both from Asian and African species have a glutamine in place of the usual distal (E7) histidine at position 64. We have isolated native oxymyoglobin directly from the skeletal muscle of African elephant (Loxodonta africana), and examined the autoxidation rate of oxymyoglobin (MbO2) to metmyoglobin (metMb) as a function of pH in 0.1 M buffer at 25 degreesC. As a result, African elephant MbO2 was found to be equally resistant to autoxidation as sperm whale myoglobin. However, the elephant myoglobin exhibited a distinct rate saturation below pH 6. Kinetic analysis of the pH profiles for the autoxidation rate has disclosed that African elephant MbO2 does not show any proton-catalyzed process, such as the one that can play a dominant role in the autoxidation reaction of sperm whale myoglobin by involving the distal histidine as its catalytic residue. Such a greater stability of African elephant MbO2 at low pH could be explained almost completely by the single H64Q mutation of sperm whale myoglobin. In African elephant aqua-metmyoglobin the Soret band was considerably broadened so as to produce another peak in the pentacoordinate 395 nm region. This unique spectral feature was therefore analyzed to show that the myoglobin is in equilibrium between two species, depending upon the presence or absence of a water molecule at the sixth coordinate position.

1H NMR study of dynamics and thermodynamics of acid-alkaline transition in ferric hemoglobin of a midge larva (Tokunagayusurika akamusi)

One of the components of hemoglobin from the larval hemolyph of Tokunagayusurika akamusi possesses naturally occurring substitution at the E7 helical position (Leu E7) [M. Fukuda, T. Takagi, K. Shikama, Biochim. Biophys. Acta 1157 (1993) 185-191]. Its oxygen affinity is almost comparable to those of mammalian myoglobins and it exhibits Bohr effect. Both acidic and alkaline forms of the ferric hemoglobin have been investigated using 1H NMR in order to gain insight into molecular mechanisms for relatively high oxygen affinity and Bohr effect of this protein. The NMR data indicated that the acidic form of the protein possesses pentacoordinated heme, and that the alkaline form possessing OH- appears with increasing the pH value. pH titration yielded a pK value of 7.2 for the acid-alkaline transition, and this value is the lowest among the values reported so far for various myoglobins and hemoglobins. The kinetic measurements of the transition revealed that the activation energy for the dissociation of the Fe-bound OH-, as well as the dissociation and association rates, decrease with increasing the pH value. These pH dependence properties are likely to be related to the Bohr effect of this protein.

Vector autoregressive modeling analysis of frequently sampled oral glucose tolerance test results. 2. Insulin resistance and secretion after gastrectomy

Using the method of vector autoregressive modeling (VAR) analysis of frequently sampled oral glucose tolerance test (OGTT) results, we evaluated abnormalities in the feedback relationships between plasma glucose and insulin in gastrectomized patients to assess insulin secretion capacity and insulin resistance following gastrectomy. VAR modeling analysis was applied to the plasma glucose and insulin level data from the frequently-sampled 75g-OGTT results of 38 subjects who had undergone total or subtotal gastrectomy and 977 controls without gastrectomy. After gastrectomy, the predicted response of insulin to a glucose challenge was excessive in normal subjects and those with slightly impaired glucose tolerance. Furthermore, the glucose response to insulin was clearly positive in gastrectomized subjects with moderately to severely impaired glucose tolerance, i.e., diabetics, indicating strong insulin resistance. The insulin resistance in this situation cannot be explained by decreased peripheral glucose disposal. Our results suggest that the lowered glucose tolerance which follows gastrectomy results from disturbance of the hormonal relationship between pancreas and intestine (entero-insular axis), which causes increased intestinal glucose absorption, and the insulin resistance which occurs in response to hyperinsulinemia in patients with normal fasting plasma glucose. Disturbance of the entero-insular axis may cause not only increased glucose absorption but also hyperglucagonemia, both of which contribute to hyperglycemia in diabetic patients after gastrectomy.