Diversity and Distribution of Rice Blast (Pyricularia oryzae Cavara) Races in Japan

In total, 310 rice blast (Pyricularia oryzae Cavara) isolates from Japan showed wide variation in virulence. Virulence on rice (Oryza sativa L.) differential varieties (DV) harboring resistance genes Pish, Pia, Pii, Pi3, Pi5(t), Pik-s, and Pi19(t) ranged from 82.9 to 100.0%. In contrast, virulence on DV possessing Pib, Pit, Pik-m, Pi1, Pik-h, Pik, Pik-p, Pi7(t), Pi9(t), Piz, Piz-5, Piz-t, Pita-2, Pita, Pi12(t), and Pi20(t) ranged from 0 to 21.6%. Cluster analysis using the reaction patterns of the DV classified isolates into three groups: I, virulent to Pik, Pik-h, Pik-p, Pik-m, Pi1, and Pi7(t); IIa, avirulent to the preceding 6 genes and virulent to Pia, Pii, Pi3, and Pi5(t); and IIb, avirulent to all 10 genes. Group I was limited to northern Japan and group IIb to central Japan, while group IIa was distributed throughout Japan. We estimate that group IIa represents the original population and that groups I and IIb arose from it through minor changes in pathogenicity. We classified these isolates into 123 races by a new designation system and conclude that the rice blast races in Japan are less diverse than previously thought.

Effect of postprandial gum chewing on diet-induced thermogenesis

OBJECTIVE

To examine the effect of postprandial gum chewing on diet-induced thermogenesis (DIT).

METHODS

Twelve healthy normal-weight males completed four trials on four different days. They chewed a 621-kcal test meal for as long as possible and as many times as possible in the slow-eating trials, while they consumed the same meal as rapidly as possible in the rapid-eating trials. In the gum-chewing trials, they chewed a 3-kcal gum for 15 min after the meal. In the non-gum-chewing trials, they consumed 3 kcal of sugar with the test meal instead of chewing the gum. DIT was calculated based on the oxygen uptake, body mass, and postprandial increments in energy expenditure above the baseline as measured before each trial.

RESULTS

DIT was significantly greater in the gum-chewing trials than in the non-gum-chewing trials for both rapid-eating and slow-eating trials. The difference in DIT between rapid-eating and slow-eating trials was greater than that between non-gum-chewing and gum-chewing trials.

CONCLUSIONS

Postprandial gum chewing enhanced DIT, but the effect of gum chewing on DIT did not exceed that of slow eating when consuming a meal.

Comparable pharmacodynamics, efficacy, and safety of linagliptin 5 mg among Japanese, Asian and white patients with type 2 diabetes

Aims/Introduction

The efficacy and safety of drugs can vary between different races or ethnic populations because of differences in the relationship of dose to exposure, pharmacodynamic response or clinical efficacy and safety. In the present post‐hoc analysis, we assessed the influence of race on the pharmacokinetics, pharmacodynamics, efficacy and safety of monotherapy with the dipeptidyl peptidase‐4 inhibitor, linagliptin, in patients with type 2 diabetes enrolled in two comparable, previously reported randomized phase III trials.

Materials and Methods

Study 1 (with a 12‐week placebo‐controlled phase) recruited Japanese patients only (linagliptin, n = 159; placebo, n = 80); study 2 (24‐week trial) enrolled Asian (non‐Japanese; linagliptin, n = 156; placebo, n = 76) and white patients (linagliptin, n = 180; placebo, n = 90).

Results

Linagliptin trough concentrations were equivalent across study and race groups, and were higher than half‐maximal inhibitory concentration, resulting in dipeptidyl peptidase‐4 inhibition >80% at trough. Linagliptin inhibited plasma dipeptidyl peptidase‐4 activity to a similar degree in study 1 and study 2. Linagliptin reduced fasting plasma glucose concentrations by a similar magnitude across groups, leading to clinically relevant reductions in glycated hemoglobin in all groups. Glycated hemoglobin levels decreased to a slightly greater extent in study 1 (Japanese) and in Asian (non‐Japanese) patients from study 2. Linagliptin had a favorable safety profile in each race group.

Conclusions

Trough exposure, pharmacodynamic response, and efficacy and safety of linagliptin monotherapy were comparable among Japanese, Asian (non‐Japanese) and white patients, confirming that the recommended 5‐mg once‐daily dose of linagliptin is appropriate for use among different race groups.

Computer-Assisted Detection of Cerebral Aneurysms in MR Angiography in a Routine Image-Reading Environment: Effects on Diagnosis by Radiologists

BACKGROUND AND PURPOSE

Experiences with computer-assisted detection of cerebral aneurysms in diagnosis by radiologists in real-life clinical environments have not been reported. The purpose of this study was to evaluate the usefulness of computer-assisted detection in a routine reading environment.

MATERIALS AND METHODS

During 39 months in a routine clinical practice environment, 2701 MR angiograms were each read by 2 radiologists by using a computer-assisted detection system. Initial interpretation was independently made without using the detection system, followed by a possible alteration of diagnosis after referring to the lesion candidate output from the system. We used the final consensus of the 2 radiologists as the reference standard. The sensitivity and specificity of radiologists before and after seeing the lesion candidates were evaluated by aneurysm- and patient-based analyses.

RESULTS

The use of the computer-assisted detection system increased the number of detected aneurysms by 9.3% (from 258 to 282). Aneurysm-based analysis revealed that the apparent sensitivity of the radiologists' diagnoses made without and with the detection system was 64% and 69%, respectively. The detection system presented 82% of the aneurysms. The detection system more frequently benefited radiologists than being detrimental.

CONCLUSIONS

Routine integration of computer-assisted detection with MR angiography for cerebral aneurysms is feasible, and radiologists can detect a number of additional cerebral aneurysms by using the detection system without a substantial decrease in their specificity. The low confidence of radiologists in the system may limit its usefulness.

Abstract P5-12-12: Hormone receptor expression level and nuclear grade associated with late recurrence in estrogen receptor-positive breast cancer patients

Background: It is not known which population of estrogen receptor (ER)-positive breast cancer patients should continue endocrine treatment beyond 5 years to overcome late recurrences. The aim of this study was to examine a combination of nuclear grade (NG) and expression level of ER and progesterone receptor (PR) to predict late recurrences.

Methods: We assessed retrospectively 1677 consecutive ER-positive/HER2-negative patients who underwent surgical resection between 2004 and 2009. Patients with T2 or larger tumor and/or node-positive received pre- or postoperative chemotherapy following the international consensus panel from the St Gallen Conference, 2003. All patients had received adjuvant endocrine treatment. NG, ER and PR statuses were determined by immunohistochemistory on surgical specimen. We classified the patients into 3 groups as follows; ER-high (+++ or Allred score 7, 8)/PR-high (++ to +++ or 5-8) (n=212), ER-high / PR-low (- to + or 3-6) (n=208), and ER-low (+ to ++ or 3-6) / PR-any (n=255). We compared distant disease-free survival (DDFS) in each cohort based on the NG (1:low, and 2 or 3: high).

Results: A median follow-up period was 77.0 months. Four hundred sixty seven patients (27.8%) received neoadjuvant chemotherapy, 208 patients (12.4%) received adjuvant chemotherapy, and 1002 patients (59.8%) did not received chemotherapy. Of the 467 patients with neoadjuvant chemotherapy, 65 patients (13.9%) had developed distant metastasis during study period (before 5 years in 51 (11.0%); and after 5 years in 14 (3.0%)). NG-low had significantly higher risk of late recurrence after 5 years than that of NG-high (p=0.005). According to hormonal receptor expression levels, in patients with NG-low, ER-low/PR-any had significantly higher overall DDFS rate than ER-high/PR-low (p=0.016). A similar trend was found before 5 years (p=0.077). However, ER-high/PR-high turned to have significantly high risk of recurrence after 5 years compared to ER-low/PR-any (p=0.024). Of the 208 patients with adjuvant chemotherapy, 16 patients (7.6%) had developed distant metastasis during study period (before 5 years in 5 (2.4%), and after 5 years in 11 (5.2%)). there was no association between a risk of recurrence and hormone receptor statuses at any study period. In the patients did not received chemotherapy, ER-high/PR-high had a trend of higher DDFS rate than others before 5 years (p=0.067). Of the 1002 patients without chemotherapy, only 36 patients (3.6%) had developed distant metastasis during study period (before 5 years in 27 (2.7%), and after 5 years in 9 (0.9%)). There was no difference of late recurrence after 5 years among the patients regardless of ER and PR expression level and NG with only low recurrence rate (0.9%).

Conclusions: Our results demonstrated that, in ER-positive/HER2-negative patients who underwent neoadjuvant chemotherapy, NG-low/ER-high/PR-high should receive extend hormonal treatment over 5 years because of the high risk of late recurrence but NG-high/ER-high might not need. Furthermore, patients with T1 and node-negative may not need extend hormonal treatment because of the extremely low risk of late recurrence regardless of NG and hormone receptor statuses.

Citation Format: Iwase M, Hayashi N, Yoshida A, Kajiura Y, Takahashi Y, Takei J, Suzuki K, Nakamura S, Yamauchi H. Hormone receptor expression level and nuclear grade associated with late recurrence in estrogen receptor-positive breast cancer patients. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-12-12.

Abstract OT1-03-02: Evaluation of the use of oral care to prevent oral mucositis in estrogen receptor positive metastatic breast cancer patients treated with everolimus: Phase III randomized control trial

Background:

In patients with estrogen receptor (ER)-positive advanced breast cancer, everolimus plus exemestane prolongs progression-free survival compared to exemestane monotherapy. However, as an adverse event from everolimus, oral mucositis (all grades) has been reported in 58% of all patients and 81% of Asian patients. Although no established prevention method is available, a previous study reported that professional oral care might prevent oral mucositis, and dentists have hypothesized that such care can reduce the occurrence of oral mucositis induced by everolimus. To evaluate this hypothesis, we compare the incidence of oral mucositis with and without professional oral care.

Method:

This is a randomized, multi-center, open-label, phase III study to evaluate the efficacy of professional oral care in preventing oral mucositis induced by everolimus in postmenopausal ER-positive metastatic breast cancer (MBC). Patients will be randomized into professional oral care and control groups (1:1 ratio). All patients will receive everolimus (10 mg daily) with exemestane (25 mg daily) and will continue everolimus until disease progression. Before the initiation of everolimus, instruction on a professional brushing method will be provided to both groups by specialists. In the professional oral care group, patients will receive teeth surface cleaning, scaling, and tongue cleaning before starting everolimus, and will continue to receive professional oral care weekly from oral surgeons throughout the 8 week treatment. In the control group, patients will brush their own teeth and gargle with 0.9% sodium chloride solution or water. The primary endpoint is the incidence of all grades of oral mucositis. The secondary endpoints are the incidence of over grade 2 and over 3 oral mucositis as determined by an oncologist and oral surgeons. The endpoints include onset and duration of oral mucositis. Major eligibility criteria include: 1) Postmenopausal women with ER positive MBC, and 2) No more than one prior chemotherapy treatment for MBC. Target accrual is 200 patients with a two-sided type I error rate of 5% and 80% power to detect 25% risk reduction. This study has just begun, and 5 of a planned 200 patients have been enrolled. (This study was registered with the UMIN 000016109).

Citation Format: Niikura N, Ohta Y, Hayashi N, Naito M, Kashiwabara K, Watanabe K, Yamashita T, Mukai H, Umeda M. Evaluation of the use of oral care to prevent oral mucositis in estrogen receptor positive metastatic breast cancer patients treated with everolimus: Phase III randomized control trial. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr OT1-03-02.

Abstract P2-08-28: Association between rim enhancement on magnetic resonance imaging and response of chemo therapy

Background: Triple-negative breast cancers (TNBC) are defined as tumors that lack expression of estrogen receptor (ER), progesterone receptor (PR), and HER2. TNBC is characterized as a cancer with a high malignancy potential and a poor prognosis. Systemic therapy that is effective in TNBC is only chemotherapy. On magnetic resonance imaging (MRI), rim enhancement was frequently seen in TNBC. It is reported that rim enhancement on MRI may associated with long-term outcome of patients with triple-negative breast cancer and may potentially serve as a prognostic biomarker in these patients. It is not well known about the relationship of rim enhancement on the MRI and treatment effectiveness of TNBC.

Purpose: We investigated the relationship between rim enhancement on MRI and response of chemo therapy and outcome in patients with TNBC.

Methods: MRI findings of 144 consecutive female TNBC patients, who underwent surgery from 2007 to 2012 in our hospital, were retrospectively reviewed. All patients have taken the MRI in our hospital before treatment, and had undergone chemotherapy before or after surgery. Presence of rim enhancement on MRI was assessed. Rim enhancement was defined more pronounced at the periphery of the mass at early phase.

Association of the presence of rim enhancement on MRI and the pathological complete response (pCR) rate in patients who underwent neo adjuvant chemotherapy (NAC) was assessed using two-sided Pearson's Chi squared tests. Disease free survival (DFS) rates were calculated by the Kaplan-Meier method. Univariate analysis was performed using the log rank test. pCR was defined as the disappearance of invasive cancer.

Results: The median age was 51yo (26-82), and the median observation period was 49 months (5-92). Eighty-one patients (56.2%) underwent NAC and 63 patients (43.7%) underwent adjuvant chemotherapy. Twenty-six cases (18.0%) occurred recurrence or distance metastasis. The presence of rim enhancement were observed 68 cases (42.3%), and non-rim enhancement were 66 cases (57.6%). DFS were not significantly different according to the presence of rim enhancement on MRI(P=0.31).

In NAC patients, 28 patients (34.5%) were led to pCR and 53 (63.4%) were non-pCR. The presence of rim enhancement were observed 44 cases (54.3%), and non-rim enhancement were 37 cases (45.6%). In pCR rate, rim enhancement is higher than non-rim enhancement (40.9%, 27.0%, respectivrly). However, the presence of rim enhancement on MRI was not significantly associated with pCR in TNBC patients (p= 0.190).

Table1. Association between rim enhancement and pCR pCR(%)non-PCR (%)P-valuerim enhancement18 (40.9)26 (59.1) non-rim enhancement10 (27.0)27 (72.9)0.19

Conclusion: The presence of rim enhancement on MRI showed high pCR rate. While, it is not a significant predictor of pCR in TNBC patients.

Citation Format: Motonari T, Yoshida A, Tsunoda H, Hayashi N, Yagata H, Yamauti H. Association between rim enhancement on magnetic resonance imaging and response of chemo therapy. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-08-28.

The real impact of telaprevir dosage on the antiviral and side effects of telaprevir, pegylated interferon and ribavirin therapy for chronic hepatitis C patients with HCV genotype 1

Triple therapy with telaprevir, pegylated interferon and ribavirin has been reported to improve antiviral efficacy but have potentially severe adverse effects in patients with chronic hepatitis C. To avoid the severe effects of telaprevir, lowering the dose has been suggested. However, impact of dosage changes on antiviral and adverse effects remains unclear. One hundred and sixty-six Japanese patients with HCV genotype 1 were treated with triple therapy. The drug exposure of each medication was calculated by averaging the dose actually taken. The overall SVR rate was 82%. The telaprevir discontinuation rate was 26%. The factors associated with discontinuation were an older age (≥65 y.o.) and a higher average dose during treatment. The telaprevir discontinuation rates were 42%, 25% and 14% in patients at ≥35, 25-35 and <25 mg/kg/day of telaprevir and 58% in older patients at ≥35 mg/kg/day of TVR. The factors associated with SVR were treatment-naïve, relapse to previous treatment, higher average telaprevir dose during treatment and completion of treatment. The SVR rate was higher, at 91%, in patients at 25-35 mg/kg/day of telaprevir than the 71% and 78% observed in those at <25 and ≥35 mg/kg/day of drug. In Japanese patients, a mean telaprevir dose of 25-35 mg/kg/day during treatment can augment its efficacy in triple therapy for patients with HCV genotype 1.

Inner ocular blood flow responses to an acute decrease in blood pressure in resting humans

Whether inner ocular vessels have an autoregulatory response to acute fluctuations in blood pressure is unclear. We tried to examine the validity of acute hypotension elicited by thigh-cuff release as to assess the dynamic autoregulation in the ocular circulation. Blood flow velocity in the superior nasal and inferior temporal retinal arterioles, and in the retinal and choroidal vasculature were measured with the aid of laser speckle flowgraphy before and immediately after an acute decrease in blood pressure in 20 healthy subjects. Acute hypotension was induced by a rapid release of bilateral thigh occlusion cuffs that had been inflated to 220 mmHg for 2 min. The ratio of the relative change in retinal and choroidal blood flow velocity to the relative change in mean arterial blood pressure (MAP) was calculated. Immediately after cuff release, the MAP and blood flows in the all ocular target vessels decreased significantly from the baseline values obtained before thigh-cuff release. The ratio of the relative change in inner ocular blood flow velocity to that in the MAP exceeded 1% / %mmHg. An explicit dynamic autoregulation in inner ocular vessels cannot be demonstrated in response to an acute hypotension induced by the thigh-cuff release technique.