20 results on '"Ishizuka, Aya"'
Search Results
2. Projections of disability-adjusted life years for major diseases due to a change in vegetable intake in 2017–2040 in Japan
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Tanaka, Shiori, Yoneoka, Daisuke, Ishizuka, Aya, Ueda, Peter, Nakamura, Keiji, Uneyama, Hisayuki, Hayashi, Naoki, Shibuya, Kenji, and Nomura, Shuhei
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- 2021
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3. Correction to: Tracking Japan’s development assistance for health, 2012–2016
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Nomura, Shuhei, Sakamoto, Haruka, Sugai, Maaya Kita, Nakamura, Haruyo, Maruyama-Sakurai, Keiko, Lee, Sangnim, Ishizuka, Aya, and Shibuya, Kenji
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- 2021
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4. Tracking Japan’s development assistance for health, 2012–2016
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Nomura, Shuhei, Sakamoto, Haruka, Sugai, Maaya Kita, Nakamura, Haruyo, Maruyama-Sakurai, Keiko, Lee, Sangnim, Ishizuka, Aya, and Shibuya, Kenji
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- 2020
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5. Forecasting disability-adjusted life years for chronic diseases: reference and alternative scenarios of salt intake for 2017–2040 in Japan
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Nomura, Shuhei, Yoneoka, Daisuke, Tanaka, Shiori, Ishizuka, Aya, Ueda, Peter, Nakamura, Keiji, Uneyama, Hisayuki, Hayashi, Naoki, and Shibuya, Kenji
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- 2020
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6. Challenges and opportunities for eliminating tuberculosis – leveraging political momentum of the UN high-level meeting on tuberculosis
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Sakamoto, Haruka, Lee, Sangnim, Ishizuka, Aya, Hinoshita, Eiji, Hori, Hiroyuki, Ishibashi, Nanao, Komada, Kenichi, Norizuki, Masataro, Katsuma, Yasushi, Akashi, Hidechika, and Shibuya, Kenji
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- 2019
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7. Japan's development cooperation for health in Vietnam: a first holistic assessment on Japan's ODA and non-ODA public resources cooperation.
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Lee, Sangnim, Ishizuka, Aya, Tachimori, Hisateru, Uechi, Manami, Akashi, Hidechika, Hinoshita, Eiji, Miyata, Hiroaki, and Shibuya, Kenji
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UNIVERSAL healthcare , *INTERNATIONAL cooperation on public health , *HEALTH policy , *FINANCING of public health , *SOCIAL history ,JAPANESE social conditions - Abstract
Background: Japan strives to strengthen its development cooperation by mobilizing various resources to assist partner countries advance on Universal Health Coverage by 2030. However, the involvement and roles of various actors for health are not clear. This study is the first to map Japan's publicly funded projects by both Official Development Assistance (ODA) and other non-ODA public funds, and to describe the intervention areas. Further, the policy implications for country-specific cooperation strategies are discussed. The development cooperation for health in Vietnam is used as a case in this study.Methods: A cross-sectional analysis of the Japanese publicly funded health projects that were being implemented in Vietnam during December 2016 was conducted. A framework of analysis based on the World Health Organization six health systems building blocks was adopted. The projects' qualitative information was also assessed.Results: Overall, 68 projects implemented through Japanese public funding were analyzed. These 68 projects under 15 types of schemes were managed by seven different scheme-operating organizations and funded by five ministries. Of these 44 (64.7%) were ODA and 24 (35.3%) were non-ODA projects. Among the recategorized six building blocks of the health system, the largest proportion of projects was health service delivery (44%), followed by health workforces (25%), and health information systems (15%). Almost half the projects were implemented together with the central hospitals as Vietnamese counterparts, which suggests that this is one area in which the specificities of Japanese cooperation are demonstrated. No synergetic effects of potential collaboration or harmonization among Japanese funded projects were captured.Conclusions: Several Japanese-funded projects addressed a wide range of health issues across all six building blocks of the health system in Vietnam. However, there is room for improvement in developing coordination and harmonization among the diversified Japanese projects. Establishing a country-specific mechanism for strategic coordination across Japanese ministries' schemes can yield efficient and effective development cooperation for health. While Vietnam's dependence on external funding is low, the importance of coordination across domestic actors of the donor countries can serve as an important lesson, especially in beneficiary countries with high external funding dependency. [ABSTRACT FROM AUTHOR]- Published
- 2021
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8. Developing and validating regression models for predicting household consumption to introduce an equitable and sustainable health insurance system in Cambodia.
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Nakamura, Haruyo, Amimo, Floriano, Yi, Siyan, Tuot, Sovannary, Yoshida, Tomoya, Tobe, Makoto, Rahman, Md. Mizanur, Yoneoka, Daisuke, Ishizuka, Aya, and Nomura, Shuhei
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- 2021
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9. Prediction of disability-adjusted life years for diseases due to low fruit intake in 2017-2040 in Japan.
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Yoneoka, Daisuke, Nomura, Shuhei, Tanaka, Shiori, Ishizuka, Aya, Peter, Ueda, Rauniyar, Santosh Kumar, Nakamura, Keiji, Uneyama, Hisayuki, Hayashi, Naoki, and Shibuya, Kenji
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RESEARCH ,RESEARCH methodology ,CARDIOVASCULAR diseases ,MEDICAL cooperation ,EVALUATION research ,SURVEYS ,COMPARATIVE studies ,FRUIT ,PEOPLE with disabilities ,QUALITY-adjusted life years - Abstract
Objective: The current study aimed to predict disability-adjusted life years (DALY) rate in Japan through 2040 with plausible future scenarios of fruit intake for neoplasms, cardiovascular diseases (CVD) and diabetes and kidney diseases (DKD).Design: Data from National Health and Nutrition Surveys and the Global Burden of Diseases study in 2017 were used. We developed an autoregressive integrated moving average model with four future scenarios. Reference scenario maintains the current trend. Best scenario assumes that the goal defined in Health Japan 21 is achieved in 2023 and is kept constant afterwards. Moderate scenario assumes that the goal is achieved in 2040. Constant scenario applies the same proportion of 2016 for the period between 2017 and 2040.Setting: DALY rates in Japan were predicted for the period between 2017 and 2040.Participants: Population aged more than than 20 years old.Results: In our reference forecast, the DALY rates in all-ages group were projected to be stable for CVD and continue increasing for neoplasms and DKD. Age group-specific DALY rates for these three disease groups were forecasted to decrease, with some exceptions. Among men aged 20-49 years, DALY attributable to CVD differed substantially between the scenarios, implying that there is a significant potential for reducing the burden of CVD by increasing fruit intake at the population level.Conclusions: Our scenario analysis shows that higher fruit intake is associated with lower disease burden in Japan. Further research is required to assess which policies and interventions can be used to achieve an increase in fruit intake as modelled in the scenarios of the current study. [ABSTRACT FROM AUTHOR]- Published
- 2021
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10. Hospital admission for type 2 diabetes mellitus under the Universal Coverage Scheme in Thailand: A time- and geographical-trend analysis, 2009–2016.
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Laowahutanon, Tanapat, Nakamura, Haruyo, Tachimori, Hisateru, Nomura, Shuhei, Liabsuetrakul, Tippawan, Lim, Apiradee, Rawdaree, Petch, Suchonwanich, Netnapis, Yamamoto, Hiroyuki, Ishizuka, Aya, Shibuya, Kenji, Miyata, Hiroaki, and Chongsuvivatwong, Virasakdi
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TYPE 2 diabetes ,INTERNATIONAL Statistical Classification of Diseases & Related Health Problems ,HOSPITAL admission & discharge ,FOOT amputation ,NOSOLOGY ,CHRONIC kidney failure - Abstract
Background: Descriptive analyses of 2009–2016 were performed using the data of the Universal Coverage Scheme (UCS) which covers nearly 70 percent of the Thai population. The analyses described the time and geographical trends of nationwide admission rates of type 2 diabetes mellitus (T2DM) and its complications, including chronic kidney disease (CKD), myocardial infarction, cerebrovascular diseases, retinopathy, cataract, and diabetic foot amputation. Methods and findings: The database of T2DM patients aged 15–100 years who were admitted between 2009 and 2016 under the UCS and that of the UCS population were retrieved for the analyses. The admitted cases of T2DM were extracted from the database using disease codes of principal and secondary diagnoses defined by the International Classification of Diseases 9th and 10th Revisions. The T2DM admission rates in 2009–2016 were the number of admissions divided by the number of the UCS population. The standardized admission rates (SARs)were further estimated in contrast to the expected number of admissions considering age and sex composition of the UCS population in each region. A linearly increased trend was found in T2DM admission rates from 2009 to 2016. Female admission rates were persistently higher than that of males. In 2016, an increase in the T2DM admission rates was observed among the older ages relative to that in 2009. Although the SARs of T2DM were generally higher in Bangkok and central regions in 2009, except that with CKD and foot amputation which had higher trends in northeastern regions, the geographical inequalities were fairly reduced by 2016. Conclusion: Admission rates of T2DM and its major complications increased in Thailand from 2009 to 2016. Although the overall geographical inequalities in the SARs of T2DM were reduced in the country, further efforts are required to improve the health system and policies focusing on risk factors and regions to manage the increasing T2DM. [ABSTRACT FROM AUTHOR]
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- 2021
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11. Tracking sectoral allocation of official development assistance: a comparative study of the 29 Development Assistance Committee countries, 2011–2018.
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Nomura, Shuhei, Sakamoto, Haruka, Ishizuka, Aya, Shimizu, Kazuki, and Shibuya, Kenji
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HEALTH policy ,INTERNATIONAL relations ,MIDDLE-income countries ,STRATEGIC planning ,HUMANITARIANISM ,WORLD health ,COMPARATIVE studies ,LOW-income countries ,DECISION making ,ENDOWMENTS ,HEALTH planning - Abstract
Background: Official development assistance (ODA) is one of the most important means for donor countries to foster diplomatic relations with low- and middle-income countries and contribute to the welfare of the international community. Objective: This study estimated the sectoral allocation of gross disbursements of ODA of the 29 Development Assistance Committee (DAC) member countries of the Organisation for Economic Co-operation and Development (OECD) for the duration of 2011 to 2018, by aid type (bilateral, multilateral, and both aids). Methods: Data from the OECD iLibrary were used. The sector definition was based on the OECD sector classification. For core funding to multilateral agencies that do not specialize in each aid sector, we estimated ODA and its flows based on the OECD methodology for calculating imputed multilateral ODA. Results: For all 29 countries, during the period of 2014–2018 where data were available for all the countries, the sector with the highest average annual ODA contribution was health at 20.34 billion USD (13.21%), followed by humanitarian aid at 18.04 billion (11.72%). Humanitarian aid has increased in the sectoral share rankings in both bilateral and multilateral aid, and the sectoral share for refugees in donor countries has increased in bilateral aid. While the 29 countries show relatively similar trends for sectoral shares, some countries and sectors display unique trends. For instance, infrastructure and energy sectors in bilateral aid of Japan are particularly high accounts for 48.48% of the total bilateral ODA of the country in 2018. Conclusions: This paper evaluated ODA trends by major donors of DAC countries in the pre-COVID-19 pandemic periods. We hope that our estimates will contribute to the review of the strategic decision-making and the effective implementation of future ODA policy discussions in the DAC countries while ensuring transparency. [ABSTRACT FROM AUTHOR]
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- 2021
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12. Limited alignment of publicly competitive disease funding with disease burden in Japan.
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Nomura, Shuhei, Yoneoka, Daisuke, Tanaka, Shiori, Makuuchi, Ryoko, Sakamoto, Haruka, Ishizuka, Aya, Nakamura, Haruyo, Kubota, Anna, and Shibuya, Kenji
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NATURAL language processing ,RUBELLA ,PUBLIC health research ,CARDIOVASCULAR diseases - Abstract
Objective: The need to align investments in health research and development (R&D) with public health needs is one of the most important public health challenges in Japan. We examined the alignment of disease-specific publicly competitive R&D funding to the disease burden in the country. Methods: We analyzed publicly available data on competitive public funding for health in 2015 and 2016 and compared it to disability-adjusted life year (DALYs) in 2016, which were obtained from the Global Burden of Disease (GBD) 2017 study. Their alignment was assessed as a percentage distribution among 22 GBD disease groups. Funding was allocated to the 22 disease groups based on natural language processing, using textual information such as project title and abstract for each research project, while considering for the frequency of information. Results: Total publicly competitive funding in health R&D in 2015 and 2016 reached 344.1 billion JPY (about 3.0 billion USD) for 32,204 awarded projects. About 49.5% of the funding was classifiable for disease-specific projects. Five GDB disease groups were significantly and relatively well-funded compared to their contributions to Japan's DALY, including neglected tropical diseases and malaria (funding vs DALY = 1.7% vs 0.0%, p<0.01) and neoplasms (28.5% vs 19.2%, p<0.001). In contrast, four GDB disease groups were significantly under-funded, including cardiovascular diseases (8.0% vs 14.8%, p<0.001) and musculoskeletal disorders (1.0% vs 11.9%, p<0.001). These percentages do not include unclassifiable funding. Conclusions: While caution is necessary as this study was not able to consider public in-house funding and the methodological uncertainties could not be ruled out, the analysis may provide a snapshot of the limited alignment between publicly competitive disease-specific funding and the disease burden in the country. The results call for greater management over the allocation of scarce resources on health R&D. DALYs will serve as a crucial, but not the only, consideration in aligning Japan's research priorities with the public health needs. In addition, the algorithms for natural language processing used in this study require continued efforts to improve accuracy. [ABSTRACT FROM AUTHOR]
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- 2020
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13. Ongoing debate on data governance principles for achieving Universal Health Coverage: a proposal to post-G20 Osaka Summit meetings.
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Nomura, Shuhei, Sakamoto, Haruka, Ishizuka, Aya, Katsuma, Yasushi, Akashi, Hidechika, and Miyata, Hiroaki
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The Group of 20 Summit (G20) in Osaka, which Japan chaired for the first time in June 2019 has created a tailwind for achieving universal health coverage (UHC) globally. In response to the rapid digitalization, the G20 leaders commenced negotiations for the Osaka Track framework to formulate international rules on data flow across borders and systematize the concept of ‘Data Free Flow with Trust (DFFT).’ The strategic harnessing of the power of data to strengthen the healthcare system can allow for rapid and affordable progress toward achieving UHC. However, world leaders have yet to discuss what data governance approaches the Osaka Track will follow, or even on what values it will seek to create and maximize. In this paper, we propose a people-centered, trust-oriented approach as the key principle of data governance toward achieving UHC, using Japan’s experience as an example. We believe that this approach is compatible with other prevailing approaches (e.g. the General Data Protection Regulation (GDPR) in the European Union), and can serve as a bridge to their conceptual differences. We hope that our proposed principles will be fully discussed in post-G20 Osaka Summit meetings. [ABSTRACT FROM AUTHOR]
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- 2020
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14. Support for UNRWA's survival
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Abdulrahim, Sawsan, Abouchacra, Kim, Afifi, Rima, Agnoletto, Vittorio, Akashi, Hidechika, Alameddine, Mohamad, Ansbro, Éimhín, Araújo-Soares, Vera, Assefi, Nassim, Baillie Smith, Matt, Bardus, Marco, Bhabha, Jacqueline, Bjertness, Espen, Blanchet, Karl, Borghi, Josephine, Busza, Joanna, Cammett, Melani, Campbell, Oona, Chaaban, Jad, Chalmers, Iain, Checchi, Francesco, Danaei, Goodarz, Dhaini, Hassan, Diaconu, Karin, Diwan, Ishac, Dominguez-Salas, Paula, Dubois, Elizabeth, El Kak, Faysal, El-Zein, Abbas, Eng, Eugenia, Eyal, Nir, Fawzi, Wafaie, Feder, Gene, Fujiya, Rika, Furukawa, Shota, Furusawa, Kiyoko, Futami, Akane, Germani, Aline, Ghattas, Hala, Giacaman, Rita, Goto, Ryunosuke, Grant, Liz, Greenough, Paul Gregg, Habib, Rima, Hagopian, Amy, Hajat, Shakoor, Hariga, Fabienne, Hatano, Ayako, Hay, Alastair, Holmboe-Ottesen, Gerd, Horiuchi, Sayaka, Hsiao, William, Huber, Daniela, Humble, Darryl, Imano, Taizo, Inoue, Yosuke, Ishizuka, Aya, Ismail, Ruba, Iwata, Rumi, Jabbour, Samer, Jamal, Diana, Jamaluddine, Zeina, Jimba, Masamine, Kabakian, Tamar, Kamiya, Yasuhiko, Karademas, Evangelos, Kashiwagi, Kenichi, Katsuma, Yasushi, Kinjo, Miyuki, Kiriya, Junko, Kitamura, Akiko, Kruk, Margaret E, Kubota, Kazumi, Langer, Ana, Leaning, Jennifer, Leng, Mhoira, Logam, Lana, Makhoul, Jihad, Matsuno, Akihisa, Matsuo, Yoshimi, McCoy, David, McGovern, Terry, McKee, Martin, McPake, Barbara, Melhem, Nada, Merriman, Anne, Michie, Susan, Millett, Christopher, Mishima, Chiaki, Miyachi, Takashi, Miyata, Hiroaki, Moodie, Rob, Morioka, Mariko, Mulholland, Kim, Mumtaz, Ghina, Murphy, Adrianna, Nagasawa, Eiji, Nagata, Kenichiro, Najem Kteily, Martine, Nakamura, Haruyo, Nakkash, Rima, Nambu, Makiko, Nava, Mica, Nelson, Erica L, Nishikida, Aiko, Nomura, Shuhei, Nozaki, Sayumi, Nuwayhid, Iman, O'Donnell, Kate, Ohashi, Masaaki, O'Laughlin, Kelli, Palmer, Jennifer, Patel, Preeti, Patel, Ronak, Pham, Phuong, Quezada-Yamamoto, Harumi, Ramia, Sami, Rawaf, Salman, Rihani, May, Roberts, Bayard, Roberts, Leslie, Ruff, Tilman A, Sahyoun, Nadine, Sakamoto, Haruka, Salti, Nisreen, Sato, Miho, Sato, Motoya, Sennett, Richard, Shallice, Tim, Shannon, Peter, Shiekh, Suhail, Shin, Kiho, Sibai, Abla M, Sieverding, Maia, Singh, Neha, Sullivan, Richard, Takahara, Takao, Tanigawa, Tomoyuki, Taniguchi, Hiroko, Testa, Adrienne, Thomas, Alban, Tsutsumi, Atsuro, Uechi, Manami, Usuki, Akira, Valente de Almeida, Sara, Wareham, Sue, Watt, Graham, West, Robert, Wigg, Peter, Wigg, Carol, Wikler, Daniel, Witter, Sophie, Yassin, Nasser, Yazdi, Youseph, Yoshino, Yasue, Yousafzai, Aisha, Yudkin, John S, Zaman, Mohammad H, and Zurayk, Huda
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- 2018
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15. 41‐5: Invited Paper: Quantum Dot Conversion Layers Through Inkjet Printing.
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Lee, Ernest, Tangirala, Ravi, Smith, Austin, Carpenter, Amanda, Hotz, Charlie, Kim, Heejae, Yurek, Jeff, Miki, Takayuki, Yoshihara, Sunao, Kizaki, Takeo, Ishizuka, Aya, and Kiyoto, Ikuro
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QUANTUM dots ,SEMICONDUCTORS ,LIGHT emitting diodes - Abstract
Quantum dot color conversion layers have the potential to greatly improve the efficiency and color performance of displays including and beyond liquid crystal displays. To fully realize these improvements, the quantum dots must be deposited and patterned at high resolution. One promising method for achieving this is through inkjet printing. In this paper we report on the fabrication and characterization of quantum dot inks, as well as films made from inkjet deposition of these materials. [ABSTRACT FROM AUTHOR]
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- 2018
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16. Incidents within community pharmacies across Japan: An analysis of the newly launched incident collecting project among community pharmacies and a comparison of causes between hospital pharmacies and community pharmacies.
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Iijima, Hisako, Ishizuka, Aya, and Maeda, Shoichi
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DRUGS , *DRUG side effects , *DRUGSTORES , *HOSPITAL pharmacies , *PATIENT safety , *DATA analysis software - Abstract
In April 2009, Japan Council for Quality Health Care (JCQHC) launched the Project to Collect Incidents within Community Pharmacies, a national project of self-and-voluntary reporting of incidents among community pharmacies. While there have been several studies and projects to collect and analyze incident reports among a set number of community pharmacies across the globe, it is still rare for an incident collecting project to exist at a national level. This paper introduces the new project in Japan. A retrospective analysis of community pharmacy participation across the country and cause of reported incidents based on the data released by JCQHC. Among the total number of reported incidents (1,460 cases), the most frequently reported incidents were related to the task of filling out prescriptions (92.0%). The most frequently answered cause of the incident was due to a "failure to check thoroughly" with 1,293 (96.3) out of 1,343 reported cases of incidents from community pharmacies. In a comparison of incidents reported between hospital pharmacies and community hospitals, both types of pharmacies reported a "failure to check thoroughly" as the leading cause of incidents. In hospital pharmacies, however, only 3,265 (84.7%) cases out of 3,857 were reported with "failure to check thoroughly" as the cause of incident. The rates between hospital pharmacy and community pharmacy for this cause differed significantly (P < 0.05). As the main cause of incidents was due to "the failure to check thoroughly", the need for confirmation systems within community pharmacies has become ever more evident. [ABSTRACT FROM AUTHOR]
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- 2011
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17. Tracking Development Assistance for Health: A Comparative Study of the 29 Development Assistance Committee Countries, 2011–2019.
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Nomura, Shuhei, Sakamoto, Haruka, Ishizuka, Aya, and Shibuya, Kenji
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- 2021
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18. The role of the G20 economies in global health.
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Akashi H, Ishizuka A, Lee S, Irie M, Oketani H, and Akashi R
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The Meetings of Health Ministers of the Group of Twenty (G20) that started at the G20 Summit in Berlin, Germany in 2017 have provided a platform for the discussion of global health matters such as antimicrobial resistance (AMR), public health emergencies, and universal health coverage. Similar issues are also discussed at meetings of the G7 and the World Health Assembly (WHA). This article will examine recent data to explore the characteristics of the G20 and its potential for improving health outcomes. G20 countries have a leading role to play in helping other countries improve global health outcomes because member countries have already faced many issues associated with aging society and increased prevalence of non-communicable diseases (NCDs). Indeed, 71% of the world's elderly population lives in the G20 countries and most of these countries have a high proportional mortality from NCDs of more than 70%. G20 countries are also responsible for a disproportionate share of global impacts. For instance, 72% of CO2 emissions are produced by G20 countries. Migration dynamics and its consequences also need to be considered from the perspective of optimizing health outcomes. Moreover, 78% of the world's top 50 pharmaceutical companies are located in the G20 countries. There is ample room for G20 countries to pursue collaborative and cooperative approaches that can complement the roles of the G7 and WHA in similar health issues. The G20 could, for example, share experiences on dealing with aging and NCDs, reduce their CO2 emissions, prohibit the production of low-quality medicines, and use standardized health check-up formats for migrants and refugees to transfer their own health information. As a group, the G20 countries have the potential to solve global health problems and other issues. The convening of high-level health meetings at G20 summits has the potential to facilitate such endeavors., (2019, National Center for Global Health and Medicine.)
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- 2019
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19. Accumulation of free complex-type N-glycans in MKN7 and MKN45 stomach cancer cells.
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Ishizuka A, Hashimto Y, Naka R, Kinoshita M, Kakehi K, Seino J, Funakoshi Y, Suzuki T, Kameyama A, and Narimatsu H
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- Biomarkers, Tumor metabolism, Cell Line, Tumor, Cell Membrane metabolism, Chromatography methods, Cytosol metabolism, Electrophoresis, Capillary, Glycosylation, Humans, Lysosomes metabolism, Models, Biological, N-Acetylneuraminic Acid chemistry, Oligosaccharides chemistry, Oligosaccharides metabolism, Polysaccharides metabolism, Gene Expression Regulation, Polysaccharides chemistry, Stomach Neoplasms metabolism
- Abstract
During the N-glycosylation reaction, it has been shown that 'free' N-glycans are generated either from lipid-linked oligosaccharides or from misfolded glycoproteins. In both cases, occurrence of high mannose-type free glycans is well-documented, and the molecular mechanism for their catabolism in the cytosol has been studied. On the other hand, little, if anything, is known with regard to the accumulation of more processed, complex-type free oligosaccharides in the cytosol of mammalian cells. During the course of comprehensive analysis of N-glycans in cancer cell membrane fractions [Naka et al. (2006) J. Proteome Res. 5, 88-97], we found that a significant amount of unusual, complex-type free N-glycans were accumulated in the stomach cancer-derived cell lines, MKN7 and MKN45. The most abundant and characteristic glycan found in these cells was determined to be NeuAcalpha2-6Galbeta1-4GlcNAcbeta1-2Manalpha1-3Manbeta1-4GlcNAc. Biochemical analyses indicated that those glycans found were cytosolic glycans derived from lysosomes due to low integrity of the lysosomal membrane. Since the accumulation of these free N-glycans was specific to only two cell lines among the various cancer cell lines examined, these cytosolic N-glycans may serve as a specific biomarker for diagnosis of specific tumours. A cytosolic sialidase, Neu2, was shown to be involved in the degradation of these sialoglycans, indicating that the cytosol of mammalian cells might be equipped for metabolism of complex-type glycans.
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- 2008
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20. Analysis of total N-glycans in cell membrane fractions of cancer cells using a combination of serotonin affinity chromatography and normal phase chromatography.
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Naka R, Kamoda S, Ishizuka A, Kinoshita M, and Kakehi K
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- Humans, Molecular Structure, N-Acetylneuraminic Acid analysis, Oligosaccharides chemistry, Tumor Cells, Cultured, Cell Membrane chemistry, Chromatography, Affinity methods, Chromatography, High Pressure Liquid methods, Neoplasms chemistry, Polysaccharides analysis, Serotonin chemistry
- Abstract
Cell surface glycans and recognition molecules of these glycans play important roles in cellular recognition and trafficking, such as in the inflammation response by sialyl LewisX oligosaccharides. Malignant cells also utilize a similar mechanism during colonization and establishment of tumor tissues in the host. These considerations prompt us to develop a screening method for comprehensive analysis of N-glycans derived from membrane fractions of cancer cells. The method involves two step separations. Initially, N-glycans released from cell membrane fractions with N-glycoamidase F were labeled with 2-aminobenzoic acid and separated based on the number of sialic acid residues attached to the oligosaccharides using affinity chromatography on a serotonin-immobilized stationary phase. Each of the nonretarded fractions containing asialo- and high-mannose type oligosaccharides and mono-, di-, tri-, and tetra-sialooligosaccharide fractions which were desialylated with neuraminidase was analyzed by a combination of HPLC using an Amide-80 column as the stationary phase and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). We analyzed total N-glycan pools of membrane fractions obtained from some cancer cells, and found that U937 cells (Histocytic lymphoma cells) expressed a large amount of oligosaccharides having polylactosamine residues and MKN45 cells (Gastric adenocarcinoma cells) contained hyper-fucosylated oligosaccharides which contained multiple fucose residues. The method described here will be a powerful technique for glycomics studies in cell surface glycoproteins, and will enable one to search marker oligosaccharides characteristically observed in various diseases such as cancer, inflammation, and congenital disorder.
- Published
- 2006
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