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Willingness-to-Pay and Costs for Novel Manual Emptying Services for Shared Onsite Sanitation Facilities in an Informal Settlement of Nairobi, Kenya
Full text linkSafely managed sanitation is essential for the environment and public health, yet emptying services for onsite sanitation are often unsafe and unaffordable. This study aims to assess the stated willingness-to-pay (WTP) for two safer manual emptying services. The first is referred to as the “Standard Plan”, a hypothetical safer manual emptying service, and the second is the “Small-amount Plan”, a hypothetical service with a volumetric limit. The service costs were also estimated to assess the financial feasibility. We surveyed 400 households in an informal settlement in Nairobi, Kenya, using a contingent valuation method: respondents answered two dichotomous questions about price bids and then a question about the maximum amount they could pay. The mean WTP for the Small-amount Plan was 0.2/drum lower than the WTP for the Standard Plan. While the WTP was lower, the estimated cost of the Small-amount Plan where emptiers can visit multiple toilets was $0.9/drum lower than the Standard Plan where emptiers visit one toilet. Our results suggest that grouping multiple toilets could be a market viable cost-reduction strategy for manual emptying and warrant further research to develop and test this approach, which may increase access to safely managed sanitation in low-income informal urban areas.ACS ES&T Water, 5(6), pp.3034-3044; 2025journal articl
Evaluating Signal Peptide Efficiency for Extracellular Protein Secretion for mRNA Vaccine Design
Full text linkmRNA vaccines have emerged as promising platforms for the prevention of infectious diseases and cancer treatment. The antigenic protein has a signal peptide added to the N-terminus for extracellular secretion. However, it remains unclear whether the optimization of signal peptides has been sufficiently compared and examined for antigen protein secretion and immunogenicity. This study investigated the effects of various signal peptides on the extracellular secretion of a model protein, NanoLuc luciferase (Nluc), in different cell lines. We compared the secretion efficiency of Nluc fused to artificial (#38 and #34) and natural signal peptides (cystatin S, lactotransferrin, and tissue plasminogen activator) in human embryonic kidney 293, C2C12, and HepG2 cells. Luciferase assays and Western blot analysis revealed that the cystatin S signal peptide consistently induced the highest secretion of Nluc among all cell types tested. Notably, the cystatin S signal peptide outperformed previously reported tissue plasminogen activator signal peptides in terms of secretion efficiency. Furthermore, we observed no correlation between Nluc secretion and mRNA expression levels for each signal peptide, suggesting that enhanced secretion was not attributable to increased transcription. Our findings highlight the potential of the cystatin S signal peptide in enhancing the extracellular secretion of antigenic proteins in mRNA vaccines by improving the efficiency of protein translation.Biological and Pharmaceutical Bulletin, 48(5), pp.706-712; 2025journal articl
Comparison of long-term health-related quality of life and symptoms between COVID-19 patients and test-negative controls during the Omicron-predominant period in Japan
Full text linkBackground: Persistent symptoms following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection affect health-related quality of life (HRQoL) and impose a substantial burden on society. While previous studies showed that both coronavirus disease 2019 (COVID-19) patients and patients with acute respiratory symptoms but negative for SARS-CoV-2 experienced persistent symptoms, evidence comparing the long-term HRQoL of COVID-19 patients with test-negative controls for SARS-CoV-2 remains limited. This study aimed to compare symptoms and HRQoL using EQ-5D-5L in both acute and chronic phases between COVID-19 patients and test-negative controls for SARS-CoV-2 during the Omicron-predominant period in Japan. Methods: Individuals aged ≥18 years tested for SARS-CoV-2 with COVID-19-like symptoms at a clinic in Tokyo, Japan, between January 2022 and January 2023, were invited an online survey. Individuals who tested positive and negative for SARS-CoV-2 were both included. Participants retrospectively recorded their physical and mental symptoms, and completed EQ-5D-5L questionnaires during the acute phase, and at months 1, 3, and 6, which were compared between COVID-19 patients and test-negative controls. Additionally, the mean EQ-5D-5L utility score was compared between male and female COVID-19 patients. Results: A total of 302 COVID-19 patients and 77 test-negative controls were included (median age: 42 years; 41.2% male; 13.2% with underlying medical conditions). At month 3, 19.9% (60/302) of COVID-19 patients and 9.1% (7/77) of test-negative controls reported ongoing symptoms. Mental symptoms and fatigue persisted for over three months among COVID-19 patients. The mean EQ-5D-5L utility score during the acute phase for COVID-19 patients was 0.615 (95% confidence interval [CI]: 0.586–0.645), and 0.874 (95% CI: 0.826–0.921) for test-negative controls, with a mean difference of –0.258 (95% CI: -0.324 to -0.193). COVID-19 patients consistently exhibited lower EQ-5D-5L utility scores than controls for over six months post-infection. Female COVID-19 patients showed lower EQ-5D-5L utility scores compared to male patients throughout the period (acute phase mean difference: -0.091; 95% CI: -0.151 to -0.031). Conclusions: COVID-19 patients experienced more symptoms three months post-testing compared to test-negative controls, with lower EQ-5D-5L utility scores persisting for over six months. Female COVID-19 patients exhibited lower EQ-5D-5L utility scores than their male counterparts throughout the period.Archives of Public Health, 83(1), art. no. 136; 2025journal articl
An Evaluation of the Cytocompatibility of Endodontic Bioceramics in Human Periodontal-Ligament-Derived Cells
Full text linkNagasaki University (長崎大学)博士(歯学)The present study evaluated the cytocompatibility of three endodontic bioceramics in human periodontal-ligament-derived cells (hPDLCs): MTA Repair HP (HP), MTA Flow White (F), and Nishika Canal Sealer BG multi (BG). In addition, we also evaluated the effect of the powder–liquid (paste) ratio of F and BG on cytocompatibility. Discs of endodontic bioceramics (diameter = 8 mm, thickness = 1 mm) were prepared with HP, F, and BG. hPDLCs obtained from extracted teeth and cultured for three to five passages were used in the experiment. The prepared discs were placed at the bottom of a 48-well plate, seeded with hPDLCs at 100,000 cells/well, cultured for 7 or 28 days, and subjected to a 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay. hPDLCs cultured without any discs were used as a negative control (NC) group. Discs made of F or BG mixed in three different consistencies were also used in this experiment. The absorbance values at days 7 and 28 were high in the order of HP > NC > BG > F. Furthermore, F or BG with higher consistency showed higher absorbance values. MTA Repair HP had the highest cytocompatibility among the three materials. Furthermore, it also showed that higher consistency improved cytocompatibility.長崎大学学位論文 学位記番号:博(医歯薬)甲第1689号 学位授与年月日:令和7年3月19日Author: Asuka Aka, Takashi Matsuura, Atsutoshi YoshimuraCitation: Journal of Functional Biomaterials, 15(8), art. no. 231; 2024Nagasaki University (長崎大学), 博士(歯学) (2025-03-19)doctoral thesi
Development of a Two-Layered Sheet Formulation of 5-Fluorouracil for Application to Rat’s Livers to Ensure Controlled Release and Local Drug Disposition
Full text linkNagasaki University (長崎大学)博士(薬学)This study aimed to develop a new and effective application form for the liver surface. We designed a two-layered sheet for the controlled release and local disposition of the anticancer drug, 5-fluorouracil (5-FU), without leakage into the peritoneal cavity. We employed poly(lactic-co-glycolic acid) (PLGA) and hydroxypropyl cellulose (HPC) to form two-layered sheets by attaching a cover sheet and a drug-containing sheet. The prepared two-layered sheets released 5-FU constantly for up to 14 d without any significant leakage from the cover side in vitro. Furthermore, we have applied sheets containing 5-FU to the rat liver surface in vivo. Notably, 5-FU could be detected in the liver attachment region even 28 d after application. The distribution ratio of 5-FU in the attachment region compared to the other liver lobes varied among the sheet formulations with different additive HPC compositions. The area under the liver concentration–time curve (AUC) of 5-FU in the attachment region from 0 to 28 d was the highest in the case of HPC 2% (w/w). This is probably due to the enhanced 5-FU released amount and controlled absorption rate from the liver surface by released HPC. No critical toxic effects were evident by the application of the two-layered sheets from the body weight change and alanine aminotransferase/aspartate aminotransferase (ALT/AST) activities. Consequently, the possible advantage of the two-layered sheets for prolonged retention of a drug in a specific region in the liver was clarified.長崎大学学位論文 学位記番号:博(医歯薬)甲第1691号 学位授与年月日:令和7年3月19日Author: Tomoaki Akagi, Yosuke Kariya, Hisashi Hamasaki, Miyako Sakaguchi, Hirotaka Miyamoto, Shintaro Fumoto, Koyo NishidaCitation: Chemical and Pharmaceutical Bulletin, 71(4), pp.277-281; 2023Nagasaki University (長崎大学), 博士(薬学) (2025-03-19)doctoral thesi
Exposure Doses among Hospitalized Patients and Medical Personnel after the Accident at the Fukushima Daiichi Nuclear Power Station
Full text linkObjectives: After the accident at Tokyo Electric Power Company’s Fukushima Daiichi Nuclear Power Station (FDNPS) in 2011, many hospitalized older patients died during or after evacuation. In this study, with the aim of exploring the concept of “tailor-made” evacuations considering individual situations after a nuclear disaster, we estimated ambient dose equivalent rate (H*(10)) data from shortly after the accident and calculated exposure doses of hospitalized patients and medical personnel in several scenarios. Methods: We used data from the Yamada district, which is located almost 4 km from the FDNPS and near 3 hospitals in which many patients died during or after evacuation. We created 10 simulation models considering differences in residential area, working hours, and distance from the workplace. Results: On March 15, 2011, H*(10) rapidly increased by more than 250 μSv/hour before steadily decreasing and reaching less than 50 μSv/hour 1 month later. None of the accumulated exposure doses in Models 1-3 reached 20 mSv. In Model 3 (hospitalized patients), the accumulated exposure doses were much less than 10 mSv. Conclusions: To minimize disaster-related incidents after a nuclear disaster, the present findings highlight the importance of establishing the concept of “tailor-made” evacuations considering individual situations.Disaster Medicine and Public Health Preparedness, 19, art. no. e139; 2025journal articl
The fecal carriage rate of extended-spectrum β-lactamase–producing or carbapenem-resistant Enterobacterales among Japanese infants in the community at the 4-month health examination in a rural city
Full text linkNagasaki University (長崎大学)博士(医学)Background: Extended-spectrum β-lactamase–producing Enterobacterales (ESBL-E) is a great public health concern globally not only in hospitals but also in the community. To our knowledge, there have been few studies on the prevalence of ESBL-E and much less about carbapenem-resistant Enterobacterales (CRE) among children in the community, and there is no such study in Japan despite such situations. This study aimed to clarify their carriage status among Japanese infants in the community by taking the opportunity of the 4-month health checkup. Methods: This prospective analysis was conducted from April 2020 to March 2021 in Shimabara City, Nagasaki Prefecture, Japan. The research-related items were mailed to all subjects with official documents for the checkup. The fecal samples were obtained from the diaper by guardians beforehand and were collected with the questionnaire and then screened for ESBL-E and CRE by a clinical laboratory company with selective agars followed by identification and confirmation. Only the positive samples were analyzed about resistant genotypes. Results: One hundred fifty infants aged 4–5 months, over half of the subjects, participated in this study. The overall ESBL-E carriage rate was 19.3% (n = 29), and no CRE carrier was detected among them. All identified ESBL-E were E. coli except for one K. pneumoniae. A significantly higher carriage rate was recorded among the infants born at “Hospital A” (25.0%) than the others (11.3%). Enterobacterales producing CTX-M-9 ± TEM were broadly distributed among the positive samples (65.5%), whereas the CTX-M-1 group was exclusively detected among those from “Hospital A”. Recursive partitioning analysis suggested that delivery facilities might be an important factor for ESBL-E colonization, although the effect could be decreased as they grow. In contrast, no significant effect was observed for other factors such as parent(s) as healthcare worker(s), having a sibling(s), and the mode of delivery. Conclusion: This study revealed the ESBL-E and CRE carriage status of Japanese infants in the community for the first time, although the setting is somewhat limited. Our findings indicated that environmental factors, especially delivery facilities, influenced ESBL-E colonization among infants aged 4–5 months, implying the need for strengthening countermeasures against antimicrobial resistance at delivery facilities and communities outside the hospitals.長崎大学学位論文 学位記番号:博(医歯薬)甲第1697号 学位授与年月日:令和7年3月19日Author: Soichiro Kawata, Shimpei Morimoto, Kosuke Kosai, Yasuhide Kawamoto, Yumiko Nakashima, Yoshitomo Morinaga, Katsunori Yanagihara, Lay-Myint Yoshida and Hiroyuki MoriuchiCitation: Frontiers in Cellular and Infection Microbiology、13, art. no. 1168451; 2023Nagasaki University (長崎大学), 博士(医学) (2025-03-19)doctoral thesi
細胞外小胞の表面抗原を利用した核酸医薬の細胞内送達法の開発
Full text linkNagasaki University (長崎大学)博士(薬科学)長崎大学学位論文 学位記番号:博(医歯薬)甲第1705号 学位授与年月日:令和7年3月19日Nagasaki University (長崎大学), 博士(薬科学) (2025-03-19)thesi
Animal medication: The passive prevention and active treatment of self and others
No full textParasites, bacteria, viruses, and other pathogens cause various diseases that affect an individual's behavior and reproductive fitness. The study of animal self-medication as a science started in the 1980s with research on primates. Since then, an increasing number of species ranging from insects to primates have shown the diversity of species medicating not only themselves but their kin and non-kin group members, leading to the recently recommended use of the more inclusive term, animal medication. Health maintenance and medication consist of prophylactic and therapeutic behaviors, including the ingestion or application to the body or placement in nests or burrows of biologically active substances; plants, animals, and minerals, of medicinal value. The medical behavioral strategies of animals can be broken down into four basic modes: (1) optimal behavioral avoidance and other forms of behavioral health maintenance; (2) passive prevention with medicinal foods; (3) direct treatment; and (4) anointment, fumigation, or wound treatment, each being performed for the control of parasites and pathogens, to improve health homeostasis and ultimately enhancing one's reproductive fitness. Modes 2, 3, and 4 behaviors are reviewed here with examples from across the animal kingdom.This is an update of Michael A. Huffman, Self-Medication: Passive Prevention and Active Treatment, Editor(s): Jae Chun Choe, Encyclopedia of Animal Behavior (Second Edition), Academics Press, 2019, Pages 696–702, ISBN 9780128132524, https://doi.org/10.1016/B978-0-12-809633-8.20883-2Reference Module in Life Sciences, 2025, https://doi.org/10.1016/B978-0-443-29068-8.00115-Xboo
Exploring the Clinical Diversity of Castleman Disease and TAFRO Syndrome: A Japanese Multicenter Study on Lymph Node Distribution Patterns
Full text link長崎大学学位論文 [学位記番号]共博（医歯薬）甲第50号 [学位授与年月日]令和7年6月4日(2025-06-04)thesi