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Satoshi Ida, Ryutaro Kaneko, Kanako Imataka, Kaoru Okubo, Yoshitaka Shirakura, Kentaro Azuma, Ryoko Fujiwara, Hiroka Takahashi, Kazuya Murata Department of Diabetes and Metabolism, Ise Red Cross Hospital, Ise-shi, Mie 516-8512, JapanCorrespondence: Satoshi IdaDepartment of Diabetes and Metabolism, Ise Red Cross Hospital, 1-471-2, Funae, 1-Chome, Ise-shi, Mie 516-8512, JapanTel +81 596-28-2171Fax +81 596-28-2965Email bboy98762006@yahoo.co.jpPurpose: To determine the frequency of social isolation (hereinafter, isolation) and homeboundness in elderly diabetic patients and to investigate their relationships with high-level functional capacity.Patients and Methods: Subjects were diabetic outpatients aged 65 years and older who were visiting the Japanese Red Cross Ise Hospital. Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC) was used to evaluate high-level functional capacity. Isolation was defined as having less than one interaction per week with someone other than co-habiting family members. Homeboundness was defined as leaving the house less than once a day. Multiple regression analysis was performed with the TMIG-IC score as the dependent variable and isolation and homeboundness as independent variables.Results: Four hundred fifty-one patients were included in the analysis. The frequency of isolation and homeboundness affected 37% and 13.3% of men and 28.9% and 20.6% of women, respectively. The adjusted partial regression coefficient of the TMIG-IC scores of isolated, homebound, and isolated+homebound men was − 0.94 [95% confidence interval (CI), − 1.68 to − 0.21; P = 0.012], − 0.27 (95% CI, − 1.93 to 1.39; P = 0.746), and − 4.03 (95% CI, − 5.37 to − 2.68; P < 0.001) in relation to that of the non-isolated and non-homebound group as reference. In women, the respective coefficients to the reference were − 1.33 (95% CI, − 2.93 to 0.25; P = 0.099), − 0.65 (95% CI, − 2.56 to 1.26; P = 0.501), and − 3.01 (95% CI, − 4.92 to − 1.1; P = 0.002), respectively.Conclusion: The frequency of isolation was high in both female and male elderly diabetic patients. In men, there was a significant relationship between isolation and decline in high-level functional capacity. In both men and women, there was a significant relationship between isolation+homeboundness and decline in high-level functional capacity.Keywords: community-dwelling elderly, Tokyo Metropolitan Institute of Gerontology Index of Competence, TMIG-IC, diabetes in the elderly, activities of daily living

Purpose: The aim of this study was to investigate the biomechanical role of trabecular bone around dental implants in the mandible. Materials and Methods: The model in this study was made using micro-computed tomography data taken from a cadaver in whom endosseous implants had been in place for 15 years prior to death. Morphologic analysis and three-dimensional (3D) finite element analysis were performed to calculate the peri-implant loading path of the model in which the trabecular structure was accurately simulated. Results: As seen through multiscale analysis using the homogenization method, the trabecular bone architecture around implants was isotropic for the most part. Also, 3D finite element analysis showed that compressive stresses oblique to the implant axis were transmitted to the lower constrained surface; tensile stresses oblique to the implant axis were transmitted to the upper constrained surface, and they intersected each other with vertical loading. The highest stress in cancellous bone was observed on perpendicular loading, and stress produced in trabeculae decreased approaching horizontal loading. Conclusion: Cancellous bone architecture around the implant was generally isotropic. 3D finite element analysis showed that cancellous bone trabeculae around implants dispersed stress by forming load transfer paths. The results suggest that trabecular bone plays a major role in supporting functional pressure exerted via the implant. [ABSTRACT FROM AUTHOR]

Ossification of spinal ligaments (OSL) is a common form of myelopathy characterized by heterotopic bone formation in the spinal ligaments, predominantly in men. Although the etiology of OSL is not fully understood, previous studies have strongly suggested the involvement of genetic factors in this disease. To investigate the possible involvement of vitamin D receptor (VDR) gene polymorphism in Japanese male patients with OSL, we analyzed: (a) the VDR genotype defined by BsmI polymorphism in patients with obvious OSL and controls; and (b) the effect of 1,25-dihydroxyvitamin D3 on alkaline phosphatase (ALP) activity of spinal ligament cells derived from patients without OSL. With regard to the VDR genotype, of the patients with OSL (n = 27), none had the BB genotype (0%), one had the Bb genotype (4%), and 26 had the bb genotype (96%). In the control group (n = 97) three had the BB genotype (3%), 18 had the Bb genotype (19%), and 76 had the bb genotype (78%). As a result, the B allele frequency in patients with OSL (2%) was significantly lower than in controls (12%). 1,25-Dihydroxyvitamin D3, at concentrations of 10-9 and 10-8 M, significantly increased ALP activity of the ligament cells (n = 8), suggesting that 1,25-dihydroxyvitamin D3 is able to promote osteogenic differentiation of normal ligament cells. Among the Japanese, sensitivity to vitamin D has been reported to vary between the alleles of the VDR; i.e., bone mineral density (BMD) in patients without the B allele is increased by vitamin D treatment, whereas patients with the B allele do not show such an increase in BMD. The present investigation is a small preliminary study, but the findings suggest, for the first time, that the B allele of the VDR acts as an inhibitor in the pathogenesis of human male OSL. [ABSTRACT FROM AUTHOR]

Introduction: In Japan, a country at the forefront of population ageing, significant geographic variation has been observed in inpatient medical expenditures for older adults aged 75 and above (IMEP75), both at the small- and large-area levels. However, our understanding of how different levels of administrative (geographic) units contribute to the overall geographic disparities remains incomplete. Thus, this study aimed to assess the degree to which geographic variation in IMEP75 can be attributed to municipality-, secondary medical area (SMA)-, and prefecture-level characteristics, and identify key factors associated with IMEP75., Methods: Using nationwide aggregate health insurance claims data of municipalities for the period of April 2018 to March 2019, we conducted a multilevel linear regression analysis with three levels: municipalities, SMA, and prefectures. The contribution of municipality-, SMA-, and prefecture-level correlates to the overall geographic variation in IMEP75 was evaluated using the proportional change in variance across six constructed models. The effects of individual factors on IMEP75 in the multilevel models were assessed by estimating beta coefficients with their 95% confidence intervals., Results: We analysed data of 1,888 municipalities, 344 SMAs, and 47 prefectures. The availability of healthcare resources at the SMA-level and broader regions to which prefectures belonged together explained 57.3% of the overall geographic variance in IMEP75, whereas the effects of factors influencing healthcare demands at the municipality-level were relatively minor, contributing an additional explanatory power of 2.5%. Factors related to long-term and end-of-life care needs and provision such as the proportion of older adults certified as needing long-term care, long-term care benefit expenditure per recipient, and the availability of hospital beds for psychiatric and chronic care and end-of-life care support at home were associated with IMEP75., Conclusion: To ameliorate the geographic variation in IMEP75 in Japan, the reallocation of healthcare resources across SMAs should be considered, and drivers of broader regional disparities need to be further explored. Moreover, healthcare systems for older adults must integrate an infrastructure of efficient long-term care and end-of-life care delivery outside hospitals to alleviate the burden on inpatient care., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Shirakura, Shobugawa and Saito.)

Background: Internet use has both positive and negative effects on mental health. However, few studies have examined the association between internet use and mental health among older adults in developing countries. This study aimed to investigate the association between Internet use and depressive symptoms among older adults in two regions of Myanmar., Methods: Data based on a visit to 1,200 older adults in urban and rural Myanmar were obtained through stratified random sampling using the cross-sectional baseline survey of the longitudinal study titled "Healthy and Active Aging in Myanmar." Our analysis included 1,186 participants. The dependent variable was depressive symptoms, and the 15-item version of the Geriatric Depression Scale (GDS) was used as a continuous variable; the higher the score, the more likely a person was to be depressed. Internet use (one of the questions about household property ownership) was used as an independent variable. After confirming the absence of multicollinearity, we adjusted for age, gender, educational background, activities of daily living, residential area, and frequency of meeting friends, and stratified by subjective economic status (above or below average). We also examined the interaction between internet use and subjective economic status. A linear regression analysis was performed., Results: Among the 1,186 participants included in the analysis (women: 59.5%; median age: 68 years old), 202 (17.0%) were Internet users (95% Confidential Interval [CI]: 0.15, 0.19), and they had significantly lower GDS scores than the participants who did not use the Internet (B: -1.59, 95% CI: -2.04, -1.13).GDS showed a negative association with Internet use even in the multivariate analysis (B: -0.95, 95% CI: -1.41, -0.50). However, the interaction term for GDS between Internet use and subjective economic status was not significantly associated (B: 0.43, 95% CI: -1.11, 1.98)., Conclusions: Internet use and depressive symptoms were associated especially among the older adults. However, there were no significant interaction between Internet use and subjective economic status for GDS., (© 2024. The Author(s).)

Objectives: This study aims to investigate whether there is a differential association between socioeconomic status (SES) and adherence to hypertension medication among older adults in rural and urban areas in Myanmar and assess what type of SES is associated with a difference., Design: Cross-sectional study using baseline data from the Japan Gerontological Evaluation Study in Myanmar prospective cohort study. A multistage random sampling method was applied in each region., Setting: An urban and a rural area in Myanmar., Participants: A total of 1200 older adults over 60 years old in Myanmar were randomly selected in 2018 (600 each from rural and urban areas). Of them, 573 had hypertension and were eligible for the analysis (urban: 317, rural: 256)., Outcome: Adherence to hypertension medication (yes/no) is the outcome of interest. Three types of SES (wealth, education and current employment status) were the independent variables., Results: We found that 21.5% of urban residents and 48.4% of rural residents were non-adherent in the study population. Poisson regression modelling stratified by area was performed to estimate the prevalence ratios (PRs) of not following treatment instructions. Demographic information and complications of hypertension were adjusted for in all models as possible confounders. In terms of SES, middle level of wealth compared with low level was significantly associated with poor adherence (PR 2.68, 95% CI 1.28 to 5.59) in the urban area, but education and employment status did not show similar associations. Lower education compared with middle/high school or higher was significantly associated with poor adherence in the rural area (no school: PR 3.22, 1.37-7.58; monastic: 3.42, 1.16-5.07; primary school: 2.41, 1.18-4.95), but wealth and income did not show similar associations., Conclusions: SES and adherence to hypertension medication were differently associated among older adults in rural and urban areas in Myanmar. To ensure healthcare access to hypertension treatment for every citizen, the differential association between SES and adherence in urban/rural areas needs to be recognised., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Following COVID-19 vaccination, ipsilateral axillary and cervical lymphadenopathy may occur, called vaccine-related hypermetabolic lymphadenopathy, which is considered reactive lymphadenopathy. We report here a case of Kikuchi-Fujimoto disease, which occurred three months after vaccination with COVID-19 vaccine. The patient had cervical and axillary lymph node enlargement and a short-term fever that resolved spontaneously after the first and second vaccines. On the 90th day after the first vaccination, the patient developed a high fever and pathologically diagnosed necrotizing lymphadenitis in the axilla, which was diagnosed as Kikuchi-Fujimoto disease. Gallium scintigraphy showed localized swelling and strong uptake in the ipsilateral axilla. It implies the possibility of Kikuchi-Fujimoto Disease in axillary drainage lymph nodes in association with COVID-19 vaccine. Although only a few cases have been reported so far, this case is novel because of its later onset and diagnosis based on pathological and gallium scintigraphy imaging findings.

Few studies have examined whether objective or subjective economic status (ES) has a greater association with the happiness of older adults, despite concerns regarding the growing economic cost of morbidity and their functional dependence in developing countries with aging populations. Thus, this study examined whether objective/subjective ES was associated with happiness in older adults in two Myanmar regions. A multistage random sampling procedure and face-to-face interviews were conducted in the urban and rural areas of Myanmar. The happiness of 1200 participants aged >60 years was evaluated using a single happiness score ranging from 0 (very unhappy) to 10 (very happy). The wealth index, used as an objective ES, was calculated from 17 household asset items, such as radio, washing machines, and television. Subjective ES was assessed by asking “Which of the following best describes your current financial situation in light of general economic conditions?” Responses ranged from “very difficult” to “very comfortable”. Both low objective and subjective ES were negatively associated with happiness, after adjusting for confounding variables and stratification by region (urban and rural areas). Although objective and subjective ES had similar associations with happiness in urban areas, subjective ES had a stronger association in rural areas.

The present study aimed to compare the effects of oral antidiabetic drugs (OADs) and glucagon-like peptide-1 receptor agonists (GLP-1RAs) on left ventricular diastolic function in patients with type 2 diabetes mellitus using a network meta-analysis of randomized controlled trials (RCTs). Literature searches were conducted on Medline, the Cochrane Controlled Trials Registry, and ClinicalTrials.gov . RCTs that assessed the effects on left ventricular diastolic function of OADs and GLP-1RAs in patients with type 2 diabetes were included. The outcome was the value (E/e') obtained by dividing peak early diastolic transmitral flow velocity (E) by the mitral annular early diastolic velocity (e'). Standardized mean differences (SMD) and 95% confidence intervals (CIs) were calculated from a random-effects network meta-analysis. Eight RCTs (592 patients) identified in a literature search met the eligibility criteria for this study and were included in the network meta-analysis. Compared with placebo, liraglutide was the only drug that caused a significant improvement in left ventricular diastolic function (SMD, - 0.65; 95% CI, - 1.23 to - 0.08). In addition, when the effects on left ventricular diastolic function were evaluated across drugs, liraglutide alone caused a significant improvement in left ventricular diastolic function compared with OADs (sitagliptin, linagliptin, pioglitazone, rosiglitazone, voglibose, and glimepiride). From the perspective of preventing the onset of heart failure, the administration of liraglutide for type 2 diabetes is promising., (© 2020. Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Although the association between SARC-F questionnaire positivity and mortality has previously been studied, the results are inconsistent. Testing the predictive validity of the SARC-F questionnaire for clinically relevant outcomes of vital prognoses is important., Aim: The objective of this study was to test the predictive validity of SARC-F by conducting a meta-analysis on the association between SARC-F, a screening tool for sarcopenia, and mortality., Methods: This meta-analysis used the MEDLINE, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, and Google Scholar databases for literature searches. Studies that examined the relationship between SARC-F questionnaire positivity and mortality and reported hazard ratios or odds ratios and 95% confidence intervals were included. A random-effects model was used for statistical analyses, and pooled hazard ratios, pooled odds ratios, and 95% confidence intervals were calculated., Results: Through the literature search, we found five studies (7501 individuals) that met the eligibility criteria for this study. The pooled hazard ratio for SARC-F questionnaire positivity and mortality was 1.87 (95% confidence interval 1.41-2.46; P < 0.001), indicating a significant association. The pooled odds ratio for SARC-F questionnaire positivity and mortality was 1.97 (95% confidence intervals 1.10-3.53; P = 0.02), showing a significant association., Conclusions: There was a significant association between SARC-F positivity and future mortality, indicating the predictive validity of the SARC-F questionnaire., Trial Registration: Not applicable.

The aim of the study was to investigate rural-urban differences in depressive symptoms in terms of the risk factors among older adults of two regions in Myanmar to provide appropriate intervention for depression depending on local characteristics. This cross-sectional study, conducted between September and December, 2018, used a multistage sampling method to recruit participants from the two regions, for face-to-face interviews. Depressive symptoms were assessed using the 15-item version of the Geriatric Depression Scale (GDS). Depressive symptoms were positively associated with living in rural areas (B = 0.42; 95% confidence interval (CI): 0.12,0.72), female (B = 0.55; 95% CI: 0.31,0.79), illness during the preceding year (B = 0.68; 95% CI: 0.45,0.91) and non-Buddhist religion (B = 0.57; 95% CI: 0.001,1.15) and protectively associated with education to middle school level or higher (B = -0.61; 95% CI: -0.94, -0.28) and the frequency of visits to religious facilities (B = -0.20; 95% CI: -0.30, -0.10). In women in urban areas, depressive symptoms were positively associated with illness during the preceding year (B = 0.78; 95% CI: 0.36, 1.20) and protectively associated with education to middle school level or higher (B = -0.67; 95% CI: -1.23, -0.11), middle or high wealth index (B = -0.92; 95% CI: -1.59, -0.25) and the frequency of visits to religious facilities (B = -0.20; 95% CI: -0.38, -0.03). In men in rural areas, illness during the preceding year was positively associated with depressive symptoms (B = 0.87; 95% CI: 0.33, 1.42). In women in rural areas, depressive symptoms were positively associated with illness during the preceding year (B = 0.83; 95% CI: 0.36, 1.30) and protectively associated with primary education (B = -0.62; 95% CI: -1.12, -0.12) and the frequency of visits to religious facilities (B = -0.44; 95% CI: -0.68, -0.21). Religion and wealth could have different levels of association with depression between older adults in the urban and rural areas and men and women. Interventions for depression in older adults should consider regional and gender differences in the roles of religion and wealth in Myanmar.

Low objective socioeconomic status (SES) has been correlated with poor physical and mental health among older adults. Some studies suggest that subjective SES is also important for ensuring sound physical and mental health among older adults. However, few studies have been conducted on the impact of both objective and subjective SES on mental health among older adults. This study examines whether objective or subjective SES is associated with depressive symptoms in older adults in Myanmar. This cross-sectional study, conducted between September and December, 2018, used a multistage sampling method to recruit participants from two regions of Myanmar, for face-to-face interviews. The Geriatric Depression Scale (GDS) was used to evaluate the depressive symptoms. Participants were classified as having no depressive symptom (GDS score <5) and having depressive symptoms (GDS score ≥5). Objective and subjective SES were assessed using the wealth index and asking participants a multiple-choice question about their current financial situation, respectively. The relationship between objective/subjective SES and depressive symptoms was examined using a multivariable logistic regression analysis. The mean age of the 1,186 participants aged 60 years and above was 69.7 (SD: 7.3), and 706 (59.5%) were female. Among them, 265 (22.3%) had depressive symptoms. After adjusting for objective SES and other covariates, only low subjective SES was positively associated with depressive symptoms (adjusted odds ratio, AOR: 4.18, 95% confidence interval, CI: 2.98-5.87). This association was stronger among participants in the rural areas (urban areas, AOR: 2.10, 95% CI: 1.08-4.05; rural areas, AOR: 5.65, 95% CI: 3.69-8.64). Subjective SES has a stronger association with depressive symptoms than objective SES, among older adults of the two regions in Myanmar, especially in the rural areas. Interventions for depression in older adults should consider regional differences in the context of subjective SES by reducing socioeconomic disparities among the communities., Competing Interests: The authors have declared that no competing interests exist.

Objective: To evaluate the effects of a multimodal treatment program on the muscle strength, physical function, and skeletal muscle mass in elderly diabetic patients with sarcopenia., Methods: Diabetic patients over 65 years old attending the Department of Diabetes and Metabolism, Ise Red Cross Hospital, were included. The diagnosis of sarcopenia was based on the Asian Working Group for Sarcopenia 2019. The measurement of extremity skeletal muscle mass was assessed by the multi-frequency bioelectrical impedance method, muscle strength was assessed by the grip strength, and the physical function was assessed by the 5-time chair stand test. The muscle strength, physical function, extremity skeletal muscle mass, and other parameters were assessed before and after 12 weeks of the multimodal treatment program (optimization of protein intake, resistance training, and patient education on sarcopenia) and then compared. Paired t-tests were used for the statistical analysis., Results: Fourteen patients (3 men and 11 women) were included in the analysis of this study. The mean age was 74.4±4.7 years old. Significant improvements in the grip strength (male, 23.2±5.6 kg to 25.6±5.5 kg, P=0.014; female, 15.5±5.0 kg to 18.9±5.0 kg, P<0.001) and 5-time chair stand test (11.2±2.5 seconds to 8.6±1.7 seconds, P=0.002) were found with the multimodal treatment program. There was also a significant decrease in HbA1c (8.1±0.7% to 7.7±0.9%, P=0.004). However, although an increasing trend in the amount of extremity skeletal muscle mass was noted, there was no significant difference., Conclusions: A multimodal treatment program for elderly diabetic patients with sarcopenia showed an improvement in the muscle strength and physical function.

Background: When considering the administration of glucagon-like peptide-1 receptor agonists (GLP-1RAs), sodium-glucose cotransporter-2 (SGLT2) inhibitors, or metformin, it is important to understand their weight loss effect as well as the degree of muscle loss caused by each drug in clinical practice., Objective: To comparatively examine the effects of GLP-1RAs and oral antidiabetic drugs, including SGLT2 inhibitors and metformin, on muscle mass and body weight in patients with type 2 diabetes via a network meta-analysis of randomized controlled trials., Methods: We included randomized controlled trials evaluating the effects of antidiabetic drugs on muscle mass and body weight. Mean difference (MD) and 95% confidence intervals (CIs) were calculated using a random-effects network meta-analysis., Results: Of the studies identified, 18 randomized controlled trials (1, 363 subjects) satisfied the eligibility criteria. In all studies, the effects of these drugs on fat-free mass (FFM) were evaluated. Therefore, FFM, which is used as an alternative index of muscle mass, was included in the study. Semaglutide (MD: -1.68, 95% CI: -2.84 to -0.52), dapagliflozin (-0.53, -0.93 to -0.13), and canagliflozin (-0.90, -1.73 to -0.07) showed a significant decrease in FFM compared with the placebo. Metformin did not show a significant decrease in FFM compared with the placebo. When compared with the placebo, semaglutide, dapagliflozin, ipragliflozin, and canagliflozin showed a significant weight loss., Conclusion: Although semaglutide, dapaglifrozin, and canagliflozin have a large weight loss effect, it is important to pay attention to muscle loss because a decrease in FFM was observed., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Objective: The purpose of this study was to investigate the relationship between a history of falls and being homebound in elderly diabetic patients., Methods: The subjects were diabetic patients ≥65 years old visiting the outpatient clinic of Ise Red Cross Hospital. Patients were defined as being confined if they went out less than once a day, and their history of falls in the past year was investigated. Adjusted odds ratios for being homebound were calculated using a logistic regression analysis with a dependent variable of being homebound and explanatory variables of a history of falls and adjustment factors (age, sex, duration of diabetes, HbA1c, cardiovascular disease, cognitive and functional decline, depression, living alone, isolation, and diabetes treatment)., Results: A total of 564 patients (319 men and 245 women) were included in the study. The numbers of patients with a history of falls and who were homebound were 198 (35.1%) and 88 (15.6%), respectively. The adjusted odds ratio for being homebound to a history of falls was 2.69 (95% confidence interval, 1.31 to 5.52; P=0.007)., Conclusion: In this study, a history of falls was significantly associated with being homebound. It is important to pay close attention to homebound elderly diabetic patients with a history of falls.

Objective: We aimed at investigating factors associated with social isolation and being homebound in older patients with diabetes., Design: Cross-sectional study., Settings: Those undergoing outpatient treatments at Ise Red Cross Hospital, Mie Prefecture., Participants: Patients with diabetes aged ≥65 years., Primary and Secondary Outcome Measures: Social isolation was defined as indulging in less than one interaction per week with individuals other than cohabiting family members. We defined homebound as going outside home less than once a day. To identify factors associated with social isolation and being homebound, we performed logistic regression analysis. The dependent variable was social isolation or homebound and independent variables were basic attributes, glycaemic parameters, complications and treatment details., Results: We analysed 558 cases (320 men and 238 women). Among these, 174 (31.2%) were socially isolated; meanwhile, 87 (15.6%) were homebound. The glycoalbumin/haemoglobin A1c ratio (OR 4.52; 95% CI 1.07 to 19.1; p=0.040) and the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC) scores (OR 0.72; 95% CI 0.57 to 0.90; p=0.006) had significant associations with social isolation. TMIG-IC scores (OR 0.78; 95% CI 0.66 to 0.92; p=0.003) and insulin use (OR 4.29; 95% CI 1.14 to 16.1; p=0.031) were associated with being homebound., Conclusion: In older patients with diabetes, glycaemic fluctuations and insulin use are associated with social isolation and being homebound, respectively. In addition, a decline in higher level functional capacity is a common factor associated with social isolation and being homebound. Thus, it is important to pay attention to social isolation and being homebound when a decline in higher level functional capacity, increased glycaemic fluctuations and insulin use in older patients with diabetes are observed., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: The purpose of the study was to adapt and psychometrically evaluate a Japanese language version of the Diabetes Caregiver Activity and Support Scale (D-CASS-J) to be culturally relevant for people with diabetes living in Japan., Methods: A Japanese translation of the original version of the D-CASS was prepared, corrected, and back-translated. Family caregivers of patients with diabetes mellitus ages ≥65 years who visited the outpatient diabetes clinic of Ise Red Cross Hospital were included. Cronbach's α coefficients were calculated as an assessment of internal consistency. Exploratory factor analyses were performed to verify construct validity. Hierarchical multiple regression analyses were performed using depression as the dependent variable and D-CASS-J and other variables as explanatory variables. Pearson's correlation coefficients between D-CASS-J scores and the support burden scale scores were calculated to verify criterion-related validity., Results: This analysis included 268 subjects. Cronbach's α coefficient was .86. Factor analyses showed the same single-factor structure as the original version of the D-CASS. Hierarchical multiple regression analyses based on the conceptual model demonstrated construct validity. D-CASS-J scores were significantly correlated with support burden scale scores., Conclusions: For family caregivers of elderly patients with diabetes in Japan, D-CASS-J can be used as a tool to evaluate difficulties experienced while providing support to patients.

Background: Falls into small water bodies can cause drowning and trauma. Such falls, especially into irrigation canals, and the subsequent trauma are common in Japan. However, few studies have investigated their characteristics, costs, and prognosis., Objective: Our aim was to clarify the characteristics, prognosis, and economic burden of trauma due to falls into irrigation canals in Kurashiki City, Japan., Methods: This 4-year, single-center, retrospective cohort study was conducted at a Japanese tertiary care hospital between January 1, 2013 and December 31, 2016. We enrolled patients who had fallen into irrigation canals constructed more than 300 years ago, and transported to our hospital by ambulance. The study outcomes included the characteristics, prognosis, and health care costs of such trauma., Results: We enrolled 266 patients with a median age of 66 years (range 19-64 years). Most patients fell into irrigation canals while walking (49.3%), riding a bicycle (35.0%), or driving or riding in a car (7.1%). Extremities were the most frequently affected body parts, and the head and chest were less frequently affected. Four patients (1.5%) died in the emergency department (ED), and 121 (45.5%) were hospitalized (109 in our hospital and 12 transferred to other hospitals). The total costs of ED and hospital stays were 777,625 US dollars (266 patients) and 712,059 US dollars (109 patients hospitalized in our hospital), respectively., Conclusions: Trauma due to falls into irrigation canals can be severe and even fatal, and the related costs are high. Our study highlights the importance of implementing appropriate measures to prevent falls into irrigation canals and of promoting awareness among citizens., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The aim of this study was to prepare a Japanese version of the "Satisfaction of Treatment among Caregivers of Dependent Type 2 Diabetic Patients" (STCD 2 -J) questionnaire, which is used to assess the satisfaction of family caregivers with respect to the treatment for elderly patients with type 2 diabetes mellitus who require support. In addition, the reliability and validity of the STCD 2 -J questionnaire were analyzed. A Japanese version of the original STCD 2 questionnaire was prepared, revised, and back-translated; the back-translated version was sent to the authors of the original version for confirmation. Family caregivers of patients with type 2 diabetes mellitus aged ≥65 years who regularly underwent medical examinations at the diabetes mellitus outpatient clinic of Ise Red Cross Hospital were included. Cronbach's α coefficient was calculated to assess internal consistency. Exploratory factor analyses were performed to assess construct validity, and Pearson's correlation coefficients between STCD 2 -J score and HbA1c as well as the degree of satisfaction with patients' blood glucose levels, depression, and negative self-assessment of nursing care were calculated to assess criterion-related validity. This study included 208 individuals (55 males and 153 females). Cronbach's α coefficient was 0.88. Factor analyses showed a single-factor structure both with and without rotation. The STCD 2 -J scores were significantly inversely correlated with HbA1c ( r = -0.27, P < 0.001). Significant correlations were observed between the STCD 2 -J scores and degree of satisfaction with patients' blood glucose levels ( r = 0.43, P < 0.001), depression ( r = -0.20, P = 0.003), and negative self-assessment of nursing care ( r = -0.19, P = 0.004). The reliability and validity of the STCD 2 -J questionnaire were confirmed. The STCD 2 -J questionnaire can be used in Japan as a tool to assess the satisfaction of family caregivers with the treatment of elderly patients with type 2 diabetes mellitus requiring support., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2020 Satoshi Ida et al.)

The aim of this study was to evaluate the effects of flash glucose monitoring on dietary variety, physical activity, and self-care behavior in patients with diabetes. This study included outpatients with diabetes using insulin who presented at the Department of Diabetes and Metabolism of the Ise Red Cross Hospital. Before initiating flash glucose monitoring and 12 weeks after its initiation, blood glucose-related parameters were assessed and self-administered questionnaires were completed (Dietary Variety Score (DVS), the International Physical Activity Questionnaire (IPAQ), the Summary of Diabetes Self-Care Activities Measure (SDSCA), and the Diabetes Treatment Satisfaction Questionnaire (DTSQ)) and compared between the two time points. We analyzed 42 patients with type 1 diabetes mellitus and 48 patients with type 2 diabetes mellitus. In patients with type 2 diabetes mellitus, but not type 1 diabetes mellitus, there was an increase in moderate/high category scores for IPAQ ( P < 0.001) and for treatment satisfaction reported via DTSQ. Furthermore, in patients with type 2 diabetes mellitus, the glycemic excursion index improved significantly and HbA1c decreased significantly (from 7.7 (1.2) to 7.4 (0.8), P = 0.025). Results showed that standard deviation and mean amplitude of glycemic excursions significantly decreased in patients with type 1 diabetes mellitus (from 71.2 (20.4) to 66.2 (17.5), P = 0.033 and from 124.6 (31.9) to 108.1 (28.4), P < 0.001, respectively). Flash glucose monitoring is a useful tool to improve physical activity in patients with type 2 diabetes., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper., (Copyright © 2020 Satoshi Ida et al.)

The patient was a 34-year-old female and was 32 weeks pregnant. She was admitted to our department because of mediastinal cyst with infection. She complained of chest pain. Chest computed tomography(CT) revealed the rapid growth of anterior mediastinal tumor. The pain increased after 2 days and magnetic resonance imaging (MRI) suggested the rupture of teratoma. After delivery by Caesarean section, we performed abscess drainage, to stabilize the patient's condition and thereafter the resection of mediastinal teratoma with partial resection of right lung was performed. Histological findings showed a mature teratoma.

Fibroblastic tumour stroma comprising mesenchymal stem cells (MSCs) and cancer-associated fibroblasts (CAFs) promotes the invasive and metastatic properties of tumour cells. Here we show that activated CD8 + T cell-derived extracellular vesicles (EVs) interrupt fibroblastic stroma-mediated tumour progression. Activated CD8 + T cells from healthy mice transiently release cytotoxic EVs causing marked attenuation of tumour invasion and metastasis by apoptotic depletion of mesenchymal tumour stromal cells. Infiltration of EV-producing CD8 + T cells is observed in neovascular areas with high mesenchymal cell density, and tumour MSC depletion is associated with preferential engulfment of CD8 + T cell EVs in this setting. Thus, CD8 + T cells have the capacity to protect tumour progression by EV-mediated depletion of mesenchymal tumour stromal cells in addition to their conventional direct cytotoxicity against tumour cells.

Background: Ingestion of glucosylceramide improves transepidermal water loss (TEWL) from the skin, but the underlying mechanism by which a small amount of dietary glucosylceramide can vastly improve skin conditions remains unclear. In a previous report, glucosylceramides were shown to be digested to sphingoids, which were shown to be absorbed through the intestinal epithelium. Based on these observations, we hypothesized that sphingoids are the key molecules facilitating endogenous ceramide production. In this study, we assessed the effect of 4,8-sphingadienine (d18:2) and 4-hydroxy-8-sphingenine (t18:1), derived from konjac glucosylceramide, on stimulating ceramide production., Methods: Konjac glucosylceramide acidolysis was performed using hydrochloric acid; the resulting d18:2 and t18:1 were fractionated by column chromatography. Real-time quantitative RT-PCR was performed to assess the effect of d18:2 and t18:1 on gene expression in normal human epidermal keratinocytes, while their effect on the nuclear receptor, peroxisome proliferator-activated receptor (PPAR)γ, was measured using a receptor-cofactor assay system. The effect of d18:2 and t18:1 on stimulating ceramide production was evaluated using HPTLC analysis in a 3-dimensional human skin model., Results: We noted the upregulation of genes related to de novo ceramide synthesis as well as of those encoding the elongases of very long-chain fatty acids by d18:2 and t18:1, but not by glucosylceramide and 4-sphingenine. Both these sphingoids also facilitated the expression of PPARβ/δ and PPARγ; moreover, they also demonstrated ligand activity for PPARγ. These results indicated that d18:2 and t18:1 promote the differentiation of keratinocytes. Analysis of the lipids within the 3-dimensional human skin model indicated that treatment with d18:2 and t18:1 not only upregulated gene expression but also increased ceramide production., Conclusions: The sphingoids d18:2 and t18:1 activated genes related to de novo ceramide synthesis and increased ceramide production, whereas glucosylceramide and 4-sphingenine could not. These results suggest that the effect of dietary glucosylceramides on the skin is mediated by d18:2 and t18:1.

Adoptive cell therapy with lymphocytes that have been genetically engineered to express tumor-reactive T-cell receptors (TCR) is a promising approach for cancer immunotherapy. We have been exploring the development of TCR gene therapy targeting cancer/testis antigens, including melanoma-associated antigen (MAGE) family antigens, that are ideal targets for adoptive T-cell therapy. The efficacy of TCR gene therapy targeting MAGE family antigens, however, has not yet been evaluated in vivo. Here, we demonstrate the in vivo antitumor activity in immunodeficient non-obese diabetic/SCID/γc(null) (NOG) mice of human lymphocytes genetically engineered to express TCR specific for the MAGE-A4 antigen. Polyclonal T cells derived from human peripheral blood mononuclear cells were transduced with the αβ TCR genes specific for MAGE-A4, then adoptively transferred into NOG mice inoculated with MAGE-A4 expressing human tumor cell lines. The transferred T cells maintained their effector function in vivo, infiltrated into tumors, and inhibited tumor growth in an antigen-specific manner. The combination of adoptive cell therapy with antigen peptide vaccination enhanced antitumor activity, with improved multifunctionality of the transferred cells. These data suggest that TCR gene therapy with MAGE-A4-specific TCR is a promising strategy to treat patients with MAGE-A4-expressing tumors; in addition, the acquisition of multifunctionality in vivo is an important factor to predict the quality of the T-cell response during adoptive therapy with human lymphocytes., (© 2011 Japanese Cancer Association.)

The carotenoid β-cryptoxanthin (β-CRX) is abundant in Satsuma mandarins (Citrus unshiu Marc). Several studies have shown a relationship between Satsuma mandarin consumption and a low risk of several diseases, for example, diabetes, gout, and hypertension, suggesting β-CRX involvement in disease prevention. We investigated the effect of β-CRX on mildly obese males. β-CRX administration reduced visceral adipose tissue, body weight, and abdominal circumference. However, the detailed mechanism by which β-CRX mediates these changes remains unknown. To identify this mechanism, we used an obese model mouse (TSOD). Oral β-CRX administration repressed body weight, abdominal adipose tissue weight, and serum lipid concentrations in TSOD; these results are identical to previous human trial results. β-CRX administration significantly repressed adipocyte hypertrophy. Gene expression analysis strongly indicated that β-CRX can alter cytokine secretion and cell proliferation. These results suggest that β-CRX derived from Satsuma mandarins can help prevent obesity by repressing hypertrophy of abdominal adipocytes.

We recently reported that the oral intake of β-cryptoxanthin exerted anti-obesity effects by lowering visceral fat levels. In the present study, we characterized the molecular mechanisms underlying the lipid-lowering effects of β-cryptoxanthin on 3T3-L1 cells. Consistent with our previous findings, β-cryptoxanthin rapidly reduced the level of intracellular lipids in 3T3-L1 cells as assessed by Oil red O staining. Using an in vitro nuclear receptor binding assay, we demonstrated the ability of β-cryptoxanthin to bind to and activate members of the retinoic acid receptor (RAR) family. Accordingly, treatment of cells with LE540, an RAR antagonist, abolished the β-cryptoxanthin-dependent suppression of 3T3-L1 adipogenesis, suggesting that β-cryptoxanthin mediates its effects on 3T3-L1 cells via RAR activation. In addition, real-time RT-PCR analysis revealed that β-cryptoxanthin down-regulates mRNA expression of PPARγ, a key regulator of adipocyte differentiation, and that this inhibition was blocked by LE540 treatment. Taken together, these data indicate that RAR activation contributes to the molecular mechanism by which β-cryptoxanthin prevents obesity.

The signal transducer and activator of transcription 5 (STAT5) is an essential factor in the signal transduction pathways for a number of cytokines that regulate the growth and differentiation of mammalian cells. In this study, we investigated the STAT5 signaling pathway in mouse embryos, to elucidate the mechanism of cytokine signal transduction that regulates preimplantation development. The results of the RT-PCR analysis showed that both STAT5A and B were expressed throughout preimplantation development. Immunocytochemistry revealed that the STAT5A/B proteins were located in the nucleus from the early 1-cell stage to the blastocyst stage. STAT5 activation appeared to be regulated by Janus kinases (JAKs) and SRC family kinases (SFKs), since inhibitors of these kinases inhibited the localization of STAT5 proteins to the nucleus. The JAK inhibitor Ag490 reduced both the developmental rate of the embryos and the expression levels of the downstream genes of the JAK-STAT5 signaling pathway. These findings suggest that STAT5 proteins function in preimplantation development by mediating the signals from cytokines.

To understand the mechanism regulating spermatozoa motility, it is important to investigate the mechanism regulating the conversion of microtubule sliding into flagellar bending. Therefore, we analyzed microtubule sliding and its conversion into flagellar bending using a demembranated spermatozoa model in which microtubule sliding and flagellar bending could be analyzed separately by treating the demembranated spermatozoa with and without dithiothreitol, respectively. Using this model, we examined the roles of cAMP and its target molecules in regulating flagellar bending and microtubule sliding. Although flagellar bending did not occur in the absence of cAMP, microtubule extrusion occurred without it, suggesting that cAMP is necessary for the conversion of microtubule sliding into flagellar bending, but not for microtubule sliding itself. The target of cAMP for regulating flagellar bending was not cAMP-dependent protein kinase (PKA), since flagellar bending was still observed in the spermatozoa treated with a PKA-specific inhibitor. Alternatively, the Epac/Rap pathway may be the target. Epac2 and Rap2 were detected in hamster spermatozoa using immunoblotting. Since Rap2 is a GTPase, we investigated the flagellar bending of demembranated spermatozoa treated with GTPgammaS. The treatment markedly increased the beat frequency and bending rate. These results suggest that cAMP activates the Epac/Rap pathway to regulate the conversion of microtubule sliding into flagellar bending.

In order to examine the involvement of leptin in the ossification of spinal ligaments (OSL), the present study examined (i) serum levels of leptin and insulin in OSL patients and controls, (ii) serum leptin levels in children of OSL females with severe obesity, (iii) the expression of leptin receptor mRNA in human spinal ligaments, and (iv) effects of leptin on cultured human ligament cells. In the OSL females, serum leptin levels were significantly higher than those of the control females, and the levels were positively correlated to the serum insulin levels, while in the control females, there was a tendency of inverse correlation. The daughters of OSL females with severe obesity also had high serum leptin levels, although they had not developed OSL. The expression of leptin receptor mRNA was confirmed in the ligaments, but leptin did not influence the alkaline phosphatase activity nor procollagen type I carboxyl-terminal peptide content of the ligament cells. These findings suggest that leptin is involved genetically and indirectly with the pathogenesis of OSL in female patients., (Copyright 2000 Academic Press.)

We recently demonstrated the renotropic activity in ovine LH isoform(s). In this study we purified porcine (p) LH isoforms and analyzed their structures and bioactivities. Purified pLH preparation (G-100 fraction 3) was dissociated into alpha- and beta-subunits, followed by isolation with reverse phase HPLC. Six components were isolated and analyzed for their amino acid compositions and amino-terminal amino acid sequences. alpha-Subunits were found to have heterogeneous N-terminal sequences, which started at Phe-1, Gly-4, Phe-6, or Thr-7. This N-terminal heterogeneity and the presence of the initial 6 amino acids has not been reported previously to the best of our knowledge. Moreover, the first 10 residues, Phe-Pro-Asp-Gly-Glu-Phe-Thr-Met-Gln-Gly, were identical with those of the ovine LH alpha subunit. At least 3 different beta-subunits were identified as heterogeneous in their carboxyl-terminal amino acids. The pLH preparation (G-100-fraction 3) was then chromatographed by an isoelectrofocusing (IEF) column. Four IEF fractions were obtained. Their amino acid structures appeared to be identical, as judged by the identical elution profiles on reverse phase HPLC, but their carbohydrate compositions were slightly different, especially in N-acetylgalactosamine in alpha-subunits. Thus, fractionation on IEF depended on the heterogeneity in carbohydrate structures. Each IEF fraction had different potencies in terms of its gonadotropic activity (in vitro) and renotropic activity (in vivo and in vitro). The discrepancy was observed not only between gonadotropic activity and renotropic activity, but also between in vivo and in vitro renotropic activity. This study identified the structural heterogeneity of pLH isoforms and demonstrated their biological heterogeneity. We concluded that the carbohydrate structure of the pLH isoform is important for expressing its biological heterogeneity (gonadotropic and renotropic activity.

An NAD-linked acetoacetyl-CoA reductase of Zoolgoea ramigera I-16-M was purified to electrophoretic homogeneity. In contrast to the D(-)-3-hydroxybutyryl-CoA-specific NADP-linked acetoacetyl-CoA reductase from the same bacterium [Saito, T. et al (1977) Arch. Microbiol. 114, 211 - 217], the purified enzyme was strictly stereospecific to L(+)-3-hydroxybutyryl-CoA, and was active not only with NAD+ but also with NADP+, although NADP+ was less effective than NAD+ as coenzyme. The enzyme showed a pH optimum at 6.3 for the reduction of acetoacetyl-CoA and at 8.0 for the oxidation of L(+)-3-hydroxybutyryl-CoA. In the reduction reaction, Km values for acetoacetyl-Coa and NADH were 8.8 microM and 6.5 microM, respectively, and in the oxidation reaction, Km values for L(+)-3-hydroxybutyryl-CoA and DNA+ were 7.0 microM and 32 microM, respectively. Among various 3-hydroxyacyl-CoAs tested, L(+)-3-hydroxybutyryl-CoA and L(+)-3-hydroxyvaleryl-CoA were the most active substrates. Poly(3-hydroxybutyrate) synthesis from acetyl-CoA, by a system reconstituted from purified preparations of 3-oxothiolase, acetoacetyl-CoA reductase and poly(3-hydroxybutyrate) synthase, was observed when the NADP-linked but not the NAD-linked reductase was used. These findings indicate that the NAD-linked acetoacetyl-CoA reductase is not directly involved in the biosynthesis of poly(3-hydroxybutyrate).

An increase in urinary flow has been observed in rats during cataleptic response to haloperidol. The present experiment was carried out to study the mechanism of haloperidol-induced diuresis. Wistar-Imamichi adult female rats were injected i.p. with haloperidol in a dose of 0.1, 1 or 10 mg/kg, and the time course of changes in urine volume was observed. The dose-dependent diuretic effect of 1 or 10 mg/kg haloperidol was significant from 4 hr afterward, and the haloperidol-induced diuresis was prevented by pretreatment with phenoxybenzamine, prazosin or yohimbine. Chlorpromazine but not spiperone and pimozide induced a significant increase in urine volume, though the effect of chlorpromazine was less marked as compared with that of haloperidol. Clonidine in a dose of 0.125-1.0 mg/kg enhanced urine flow markedly from 30 min, and the same alpha-adrenergic blockers were also effective in blocking the diuretic effect of clonidine. Urinary osmolarity in 1 mg/kg haloperidol- and 0.125 mg/kg clonidine-treated rats decreased significantly, whereas only clonidine stimulated urinary Na and K excretion. Plasma osmolarity and negative free water clearance did not change in both haloperidol- and clonidine-treated rats. The present results suggest that the haloperidol-induced diuretic effect could be due to the central alpha-adrenoceptor blocking action of haloperidol.

The extracellular poly(3-hydroxybutyrate) depolymerase purified from Alcaligenes faecalis T1 has two disulfide bonds, one of which appears to be necessary for the full enzyme activity. This depolymerase hydrolyzed not only hydrophobic poly(3-hydroxybutyrate) but also water-soluble trimer and larger oligomers of D-(-)-3-hydroxybutyrate, regardless of their solubilities in water. Kinetic analyses with oligomers of various sizes indicated that the substrate cleaving site of the enzyme consisted of four subsites with individual affinities for monomer units of the substrate. Analyses of the hydrolytic products of oligomers, which had labeled D-(-)-3-hydroxybutyrate at the hydroxy terminus, showed that the enzyme cleaved only the second ester linkage from the hydroxy terminus of the trimer and tetramer, and acted as an endo-type hydrolase toward the pentamer and higher oligomers. The enzyme appeared to have a hydrophobic site which interacted with poly(3-hydroxybutyrate) and determined the affinity of the enzyme toward the hydrophobic substrate.

The extracellular poly(3-hydroxybutyrate) depolymerase of Alcaligenes faecalis T1, which hydrolyzes both hydrophobic poly(3-hydroxybutyrate) and water-soluble oligomers of D(-)-3-hydroxybutyrate, lost its hydrolyzing activity toward the hydrophobic substrate on mile trypsin treatment, but retained its activity toward water-soluble oligomers. The molecular mass of the trypsin-treated enzyme was 44 kDa, as estimated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, which was 6 kDa smaller than that of the native enzyme (50 kDa). The trypsin-treated enzyme seemed to be less hydrophobic than the native one, because it was rather weakly adsorbed to a hydrophobic butyl-Toyopearl column compared with the native enzyme, and showed no ability to bind to poly(3-hydroxybutyrate), to which the native enzyme tightly bound. These results suggest that, in addition to a catalytic site, the enzyme has a hydrophobic site, which is not essential for the hydrolysis of water-soluble oligomers, but is necessary for the hydrolysis of hydrophobic substrates, and this hydrophobic site is removed from the enzyme by the action of trypsin.

A strain of Alcaligenes faecalis secretes an extracellular D(-)-3-hydroxybutyrate oligomer hydrolase, in addition to poly(3-hydroxybutyrate) depolymerase, when it is grown in a medium containing poly(3-hydroxybutyrate) as the sole carbon source. The oligomer hydrolase (EC 3.1.1.22), which has been purified to electrophoretic homogeneity, has a molecular weight of 68 000, as estimated by Sephadex G-100 gel filtration, and of 74 000, by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The isoelectric point of the enzyme is approx. 6.0 and the pH optimum for the enzyme reaction is 8.5. The purified oligomer hydrolase has high affinity for oligomeric esters (apparent Km for the D(-)-3-hydroxybutyrate dimer = 32.8 microM; for the dodecamer = 1.3 microM), but does not attack poly(3-hydroxybutyrate) (average molecular weight, 32 500) at all. Analysis of hydrolysates of the oligomeric esters suggests that the enzyme hydrolyzes these substrates from the carboxyl terminus, releasing D(-)-3-hydroxybutyrate units one by one.

Extracellular poly(3-hydroxybutyrate) depolymerase was purified from the culture medium of Peudomonas lemoignei and separated into four isozymes (A1, A2, B1 and B2) by CM-Sepharose CL-6B chromatography. The molecular weights of A1 and A2 and those of B1 and B2 were estimated to be 54 000 and 58 000, respectively, by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The isoelectric points of A1, A2, B1 and B2 were found to be approximately pH 9.7, 10.0, 10.0 and 10.6, respectively, by isoelectric focusing. All four enzymes hydrolyzed poly(3-hydroxybutyrate) and oligomeric esters of D-(-)-3-hydroxybutyrate, but showed no activity toward the dimeric ester. Analysis of hydrolytic products of the oligomeric esters with A1 and B2 suggested that the enzymes hydrolyzed mainly the second and third ester bonds from the free hydroxy terminus at different frequencies, depending upon the chain length of the substrates.

A strain of Alcaligenes faecalis T1, which was isolated from activated sludge, excreted an extracellular poly(3-hydroxybutyrate) depolymerase as it grew in a medium containing poly(3-hydroxybutyrate) as the sole carbon source. The molecular weight of the enzyme, purified from the culture medium to electrophoretic homogeneity, was 48 000 as determined by Sephadex G-100 filtration, and 50 000 by polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate. The pH optimum for the enzyme reaction was 7.5. The purified enzyme depolymerized poly(3-hydroxybutyrate) purified from Zoogloea ramigera 1-16-M, but did not attack the bacterial native poly(3-hydroxybutyrate)-containing granules. Km values were 13.3 micrograms/ml (= 0.78 microM, based on an estimated average molecular weight of 17 000) for poly(3-hydroxybutyrate) and 5.4 mM for the trimeric ester of D(--)-3-hydroxybutyric acid. Analysis of hydrolytic products of poly(3-hydroxybutyrate), several oligomeric esters of D(--)-3-hydroxybutyric acid, and the methyl ester of the trimeric ester indicated that the enzyme hydrolyzed these substrates from the free hydroxyl terminus, releasing D(--)-3-hydroxybutyrate dimer units one at a time.