The importance of the use of stem cells for public health

Stem cells were elected 'Breakthrough of the Year' by Science(1) magazine in 1999, having shown that stem cells from adult tissues retained the ability to differentiate into other tissue types. During the previous year, the first human embryo stem cell lines were established. Since then, the number of scientific papers on stem cells has been increasing exponentially, establishing new paradigms that are rapidly challenged by subsequent experiments. This paper reviews the stem cell research field, divided into two groups: embryo and adult stem cells. While the differentiation potential of the former is well characterized in mice and humans, their use in cell therapy and research has been hampered by histocompatibility, safety and ethical issues. In contrast, adult stem cells do not present these problems. However, the extent of their plasticity is still under investigation. Nevertheless, numerous clinical trials in humans are under way, mainly with stem cells derived from bone marrow. This paper discusses discuss the importance of working with both classes of human stem cells in order to fulfill the promise of stem cell therapies.     

Fresh or frozen? Classifying ‘spare’ embryos for donation to human embryonic stem cell research

United Kingdom (UK) funding to build human embryonic stem cell (hESC) derivation labs within assisted conception units (ACU) was intended to facilitate the 'In-vitro fertilisation (IVF)-stem cell interface', including the flow of fresh 'spare' embryos to stem cell labs. However, in the three sites reported on here, which received this funding, most of the embryos used for hESC research came from long term cryopreservation storage and/or outside clinics. In this paper we explore some of the clinical, technical, social and ethical factors that might help to explain this situation. We report from our qualitative study of the ethical frameworks for approaching women/couples for donation of embryos to stem cell research. Members of staff took part in 44 interviews and six ethics discussion groups held at our study sites between February 2008 and October 2009. We focus here on their articulations of social and ethical, as well as scientific, dimensions in the contingent classification of 'spare' embryos, entailing uncertainty, fluidity and naturalisation in classifying work. Social and ethical factors include acknowledging and responding to uncertainty in classifying embryos; retaining 'fluidity' in the grading system to give embryos 'every chance'; tensions between standardisation and variation in enacting a 'fair' grading system; enhancement of patient choice and control, and prevention of regret; and incorporation of patients' values in construction of ethically acceptable embryo 'spareness' ('frozen' embryos, and embryos determined through preimplantation genetic diagnosis (PGD) to be genetically 'affected'). We argue that the success of the 'built moral environment' of ACU with adjoining stem cell laboratories building projects intended to facilitate the 'IVF-stem cell interface' may depend not only on architecture, but also on the part such social and ethical factors play in configuration of embryos as particular kinds of moral work objects.     

无动物源性培养系统对人胚胎干细胞生长的支持作用

目的:建立完全非动物源性培养系统,为人胚胎干细胞定向诱导为各系统细胞应用于临床、消除动物源性污染打下基础。方法:分别采用人包皮成纤维细胞、胎儿肌肉细胞及人子宫内膜基质细胞为饲养层细胞,以血清替代品取代动物血清,支持人胚胎干细胞生长,观察其增殖和分化情况。结果:人包皮成纤维细胞、胎儿肌肉细胞均能很好支持人胚胎干细胞生长增殖,并保持90%左右未分化表型:AKP染色强阳性,SSEA-4、TRA-1-81表达强阳性,可见OCT-4 mRNA表达,核型正常。人子宫内膜基质细胞不能支持hESC的生长。结论:完全可以使用非动物源性培养系统支持人胚胎干细胞增殖,从而为胚胎干细胞定向诱导分化应用于临床打下坚实基础     

Fresh or frozen? Classifying ‘spare’ embryos for donation to human embryonic stem cell research

United Kingdom (UK) funding to build human embryonic stem cell (hESC) derivation labs within assisted conception units (ACU) was intended to facilitate the ‘In-vitro fertilisation (IVF)-stem cell interface’, including the flow of fresh ‘spare’ embryos to stem cell labs. However, in the three sites reported on here, which received this funding, most of the embryos used for hESC research came from long term cryopreservation storage and/or outside clinics. In this paper we explore some of the clinical, technical, social and ethical factors that might help to explain this situation. We report from our qualitative study of the ethical frameworks for approaching women/couples for donation of embryos to stem cell research. Members of staff took part in 44 interviews and six ethics discussion groups held at our study sites between February 2008 and October 2009. We focus here on their articulations of social and ethical, as well as scientific, dimensions in the contingent classification of ‘spare’ embryos, entailing uncertainty, fluidity and naturalisation in classifying work. Social and ethical factors include acknowledging and responding to uncertainty in classifying embryos; retaining ‘fluidity’ in the grading system to give embryos ‘every chance’; tensions between standardisation and variation in enacting a ‘fair’ grading system; enhancement of patient choice and control, and prevention of regret; and incorporation of patients’ values in construction of ethically acceptable embryo ‘spareness’ (‘frozen’ embryos, and embryos determined through preimplantation genetic diagnosis (PGD) to be genetically ‘affected’). We argue that the success of the ‘built moral environment’ of ACU with adjoining stem cell laboratories building projects intended to facilitate the ‘IVF-stem cell interface’ may depend not only on architecture, but also on the part such social and ethical factors play in configuration of embryos as particular kinds of moral work objects.     

Human embryonic stem cell science and policy: The case of Iran

The paper is based on a large qualitative study of ethics, policy and regulation of human embryonic stem cell (hESC) science in Iran. This case study in five academic research centres used semi-structured interviews to examine in depth the views of stem cell scientists, embryologists and ethics committee members on hESC research policy in this Shia Muslim country. Although Iran's policy approach has been considered 'intermediate', what is described here seems to be a 'more flexible' policy on hESC science. This article describes three arguments to explain why Iran has shaped such a policy. These are: (1) a flexibility of the Shia tradition has allowed for hESC science; (2) permissive policy related to other fields of biomedicine, such as new assisted reproductive technologies, facilitated approval of hESC research; and (3) a lack of public debate of bioscience in Iran influences how its hESC research policy is perceived. Based on the empirical data, this paper then expands and refines the conceptual bioethical basis for the co-production of science, policy, and society in Iran. The notion of co-production implies that scientists, policy-makers, and sometimes other societal actors cooperate in the exchange, production, and application of knowledge to make science policy.     

Enteropathogenic Escherichia coli Outbreak and its Incubation Period: Is it Short or Long?

ObjectivesThe aim of this study is to determine the incubation period of enteropathogenic Escherichia coli (EPEC), which creates several outbreaks in a year in South Korea.MethodsWe reviewed all water and food-borne outbreaks data reported to the Korea Centers for Disease Control and Prevention (KCDC) from 2009 to 2010 and determined their characteristics. Through this process, we can presume the incubation period of EPEC among outbreaks in South Korea.ResultsA total of 497 water and food-borne outbreaks were reported to KCDC and 66 (13.28%) are defined as E coli-origin outbreaks. EPEC was the most common subtype of E coli, being confirmed as a causative organism in 26 outbreaks. Overall attack rate was 15.85% (range 0.9–100). The subjects were eight outbreaks that have a clear history of single exposure and we can estimate the incubation time of EPEC as minimum 0.5 hours to maximum 34.0 hours with a mean 12.9 hours (range 4.5–24.0). The cases of those cannot completely rule out the chance of multiple exposure from same source or place have minimum 1.0 hour, to a maximum of 195.5 hours and a mean 30.5 (range 22.7–61.0) hours of incubation period.ConclusionsThis serial analysis suggests that EPEC has actually shorter mean incubation period as much as 12 hours. When this period is longer than 1 day or over, then the epidemiologic investigator should consider the chance of repeated or continuous exposure by making it clear whether there is any chance of any other exposure in common.     

昆明鼠胚胎干细胞系建立中原代克隆生长及其传代方法的研究

目的:探讨昆明鼠胚胎内细胞团分离方法、原代干细胞克隆分离时机及干细胞传代方法对干细胞建系效率的影响。方法:取昆明鼠3.5d囊胚建胚胎干细胞系,比较全胚培养法与免疫外科法两种内细胞团分离方法对胚胎干细胞建系效率的影响,观察原代克隆的分离时机,机械法传代和酶消化传代对胚胎干细胞建系效率的影响。结果:全胚培养法30个囊胚建系3个,免疫外科法32个囊胚建系4个,两组均可以有效地形成胚胎干细胞系;昆明鼠原代干细胞克隆分离最佳时机是增殖4～6d;5代以前的干细胞以机械传代方法较好,5代后用酶消化法传代效果较好。结论:全胚培养法和免疫外科法均能有效建立昆明鼠胚胎干细胞系,采用机械化与酶消化法相结合传代更适合昆明鼠干细胞建系。     

Stammzellbasierte In-vitro-Modelle als Ersatz für Tiermodelle bei Toxizitäts- und Wirksamkeitsprüfungen

Regarding toxicity and efficacy tests of pharmacological and chemical substances (REACH legislation in Europe), there is a strong need to develop alternative methods for animal in vivo studies, in particular for human in vitro models. Here we present results from early phases of projects exploring the potential of embryonic stem cell models, with a special emphasis on embryo toxicity and neuronal stress.We have been able to demonstrate key functional read-outs of neural hESC models, in addition to representing mechanistic aspects which are characteristic for ischemia or excitotoxicity. There is agreement that these mechanisms underlie a variety of human neurodegenerative diseases. We discuss the possibilities to develop more precise endpoints on the molecular level and present an example of a protein biomarker signature emerging from a European FP6 project about embryo toxicity (www.reprotect.eu), employing murine and human embryonic stem cell models.     

Epidemic Intelligence Service Officers and Field Epidemiology Training Program in Korea

Korea has adopted Epidemic Intelligence Service (EIS) officers through the Field Epidemiology Training Program (FETP) since 1999 for systematic control of emerging and re-emerging infectious diseases. Graduates of medical schools in Korea are selected and serve as public health doctors (PHDs) for their mandatory military service. The duration of service is 3 years and PHDs comprise general practitioners and specialists. Some PHDs are selected as EIS officers with 3 weeks basic FETP training and work for central and provincial public health authorities to conduct epidemiological investigations. The total number of EIS officers is 31 as of 2012. The Korea Centers for Disease Control and Prevention (KCDC) has 12 specialists, whereas specialists and each province has one or two EIS officers to administer local epidemiological investigations in 253 public health centers. The Korean EIS officers have successfully responded and prevented infectious diseases, but there is a unique limitation: the number of PHDs in Korea is decreasing and PHDs are not allowed to stay outside Korea, which makes it difficult to cope with overseas infectious diseases. Furthermore, after 3 years service, they quit and their experiences are not accumulated. KCDC has hired full-time EIS officers since 2012 to overcome this limitation.     

Forschung ja – Anwendung nein?

In exceptional cases, the German Stem Cell Act allows research on human embryonic stem cells. However, it does not allow the implementation of the research results if this in turn requires the use of further embryonic stem cell lines. It has, in the meantime, transpired that such research results could be of concrete use. Thus, in the distant future, it could be used in the clinical treatment of patients. Already in the nearer future the use of human embryonic stem cell lines can be envisaged for both the development and testing of medicines as well as in the field of toxicology. To this end, research concerning embryo toxicity and neurotoxicity is ground-breaking. The toxicological and pharmacological use of human embryonic stem cell lines should serve the protection of human health as well as the safe and reliable use of medicines. In addition, animal experiments could be reduced, which is desirable from a point of view of animal protection ethics. Since research on human embryonic stem cell lines is actually permitted in Germany, the use of the respective research results should be allowed all the more. This follows from the basic human right to health protection and health care. Legal ambiguities, which still exist in this respect, should be removed.     

Policies and innovations to battle Covid-19 – A case study of South Korea

ObjectivesTo describe how health care crisis resulting from the COVID-19 pandemic in South Korea has led to innovation and changes to government policy. This paper presents the significant cluster events, relevant developments of innovation, and economical impact in Korea that could inform policy makers on how to respond to health crises in the future.MethodsHealth care, economy, epidemiological data are collected from various sources including the Korea Centers for Disease Control and Prevention (KCDC) or other government sources.ResultsThe KCDC jointly with medical professionals developed a series of innovations such as 1) Full contact tracing and rapid testing with a 12 h turnaround and 10 min movement tracking systems, 2) transparent disclosure of all contract tracing data to the public through a central database, 3) Drive-Through and Walk-Through testing methods, and 4) a 4 tier patient severity index and community treatment isolation centers. Korea moved from the 4th in the world for total confirmed cases in March down to 76th in August.ConclusionsExpedited enforcement of amended legislation acts to protect the healthcare workforce resulted in only 10 healthcare professionals contracting the virus while caring for Covid-19 patients. This has resulted in minimal human capital loss and the government was able to re-direct existing medical workforce to areas in need. The quarantine strategies implemented resulted in little need to lock down the whole economy but also limited the cost spent to gain a year of life to 193,848 Won (US$163).     

A Study on the Relapse Rate of Tuberculosis and Related Factors in Korea Using Nationwide Tuberculosis Notification Data

ObjectivesFrom the perspective of public health, tuberculosis (TB) remains an important issue that threatens health. Korea is an intermediate burden country with a TB incidence of 97/100,000 individuals. Among many TB control measures, a relapse rate of TB is one indicator that can be used to indirectly assess the level of TB control in countries and in communities. Relapse TB has an approximately 12% yearly incidence in Korea. This study aims to estimate the relapse rate of TB and to investigate the associated factors by using nationwide TB notification data in Korea.MethodsThe nationwide TB notification data in 2005 was used with the exclusion criteria of duplicated reporting, foreign-born patients, outcome–died, and outcome–diagnosis changed. The data were double-checked as to whether they were reported again during 2006–2010 and the estimated relapse rate of TB. Associated factors were analyzed by multivariate logistic regression with the variables of age, sex, registration type, results of sputum smear test, medication, and outcome of treatment.ResultsAmong 45,434 TB patients in 2005, 4,371 patients were again reported as TB patients from 2006 to 2010. Five hundred and sixty-four patients were reported more than twice and the cumulative number of relapses was 5,072 cases. The 5-year relapse rate was estimated as 9.62%. The relapse rate decreased yearly: 4.8% in 2006, 2.4% in 2007, 1.6% in 2008, 1.4% in 2009, and 1.0% in 2010. Age, sex, registration type, tuberculosis type, and medication were independently associated with a relapse of TB. In the multivariate logistic regression analysis, the following factors were related: male sex, 40–49 years old; registration type, relapse, treatment after failure, treatment after default, transfer in, and other, the sputum smear-positive pulmonary TB, and medications (including individuals taking 2–5 drugs).ConclusionThis study has estimated a 5-year relapse rate of TB in Korea that is slightly lower than the rate of relapse TB in the annual reports. This study could be conducted and cross-checked with data from the National Health Insurance in the future.     

Epidemiological Characteristics of Imported Shigellosis in Korea, 2010–2011

Shigellosis is a global disease as food poisoning by infection of Shigella spp (S. dysenteriae, S. flexneri, S. boydii and S. sonnei). In Korea, approximately 500 cases of shigellosis have reported every year since 2004, and imported shigellosis is increasing gradually from 2006 in particular. According to increase of numbers of overseas travelers, the numbers of patients diseased with imported shigellosis is also increasing. We need continuous surveillance studies network (SSN) for control of imported shigellosis. We studied epidemiological characteristic of imported shigellosis by using database of Korea Centers for Disease Control and Prevention (KCDC) from 2010 to 2011. The imported shigellosis is analyzed on correlation with variable factors such as sex, age, symptom, visited country as well as Shigella spp in the database. Total 399 patients diseased with shigellosis have been reported between 2010 and 2011, The 212 patients (53.1%) among them were disease with imported shigellosis and the 205 patients (96.7%) were diagnosed as definite shigellosis. Shigella sonnei (65.6%) and Shigella flexneri (20.3%) were isolated in order. Clinical symptoms of the shigellosis were diarrhea (96.5%), abdominal pain (54.7%), fever (52.8%), chill (31.6%), and weakness (21.7% etc) in order. Duration of diarrhea was 1 to 5 days, the number of diarrhea was mostly more than 10 times, and type of stool was almost yellow stool. Almost shigellosis was occurred in the travelers visited to Asia (98.1%). Particularly, the occurrence rate of shigellosis was highest in traveler visited to Southeast Asia which is India (21.7%), Cambodia (19.8%), Philippines (17.9%), and Vietnam (9.0%) in order. According to increase of traveler to Southeast Asia, imported Shigellosis also increased. We need to strengthen the public health and hygiene, which is infection prevention rules, eating properly-cook food, washing hands, drinking boiled water, for traveler to Asia. The quarantine and surveillance system to control imported shigellosis is need continually in Korea.     

The derivation and potential use of human embryonic stem cells

Human embryonic stem cells lines can be derived from human blastocysts at high efficiency (>50%) by immunosurgical isolation of the inner cell mass and culture on embryonic fibroblast cell lines. These cells will spontaneously differentiate into all the primary embryonic lineages in vitro and in vivo, but they are unable to form an integrated embryo or body plan by themselves or when combined with trophectoderm cells. They may be directed into a number of specific cell types and this enrichment process requires specific growth factors, cell-surface molecules, matrix molecules and secreted products of other cell types. Embryonic stem (ES) cells are immortal and represent a major potential for cell therapies for regenerative medicine. Their use in transplantation may depend on the formation of a large bank of suitable human leucocyte antigen (HLA) types or the genetic erasure of their HLA expression. Successful transplantation may also require induction of tolerance in recipients and ongoing immune suppression. Although it is possible to customize ES cells by therapeutic cloning or cytoplasmic transfer, it would appear unlikely that these strategies will be used extensively for producing ES cells compatible for transplantation. Embryonic stem cell research may deliver a new pathway for regenerative medicine.     

Elimination of measles--South Korea, 2001-2006

Before the introduction of measles-containing vaccine (MCV), measles was endemic in South Korea. MCV became available in South Korea in 1965, and measles, mumps, and rubella (MMR) vaccine was added to the country's national immunization program in 1983, with 1 dose administered at age 9-15 months. In 1997, a second dose of MCV (MCV2) was added to the schedule; recommended ages for administration of MCV1 and MCV2 were 12-15 months and 4-6 years, respectively. However, with insufficient policies and programs in place to promote 2-dose coverage, this 1997 recommendation achieved limited coverage with 2 doses of MCV. In a 2000 seroepidemiologic study among children aged 7-9 years who had been eligible for vaccination since 1997, only 39% had received MCV2 (Korea Centers for Disease Control and Prevention [KCDC], unpublished data, 2001). During 2000-2001, South Korea experienced a measles epidemic that affected tens of thousands of children. In response, in 2001, South Korea announced a 5-year National Measles Elimination Plan. This report describes the activities and summarizes the results of that plan, which enabled South Korea to announce in late 2006 that interruption of indigenous measles transmission had been achieved, making South Korea the first country in the World Health Organization's (WHO) Western Pacific Region declare measles eliminated.     

Humane embryonale Stammzellen im Kontext internationaler Forschungsaktivitäten

Research involving pluripotent human embryonic stem cells (hESCs) is a rapidly growing field of science. Since hESCs originate from early human embryos, alternative methods for producing pluripotent cells have been developed. This article introduces some of those strategies and, in addition, covers international efforts to establish consistent international standards for cultivation, characterization and preservation of hESCs. Furthermore, global trends to form networks in the field of stem cell research as well as endeavors to harmonize ethical standards for hESC research are presented. Finally, potential applications of hESCs in the field of pharmacology/toxicology are discussed as well as recent results of animal studies using hESCs.     

胚胎干细胞专利相关信息分析

目的对1985年至2004年12月的胚胎干细胞相关专利信息进行详细阅渎和分析,了解国内、外胚胎干细胞相关专利的情况。方法以干细胞及胚胎干细胞为主题词,以德文特(Der- went)数据库为背景,对多个专利数据库进行检索、筛查和分类,建立胚胎干细胞专利数据库。从专利的角度入手,对数据库中的630篇国际及44篇国内胚胎干细胞专利文献进行分类分析。结果胚胎干细胞研究领域的专利申请情况总体呈上升趋势;申请范围主要涉及动物细胞或组织、修饰的细胞、脊椎动物新品种及未分化的人类/动物细胞等方面,国际(13.4%)和国内(20.9%)申请均以涉及动物细胞或组织的占据首位;国内申请中涉及未分化的人/动物细胞的专利较多(19.8%);转基因动物、细胞建系及核移植技术相关的专利申请是胚胎干细胞相关专利中的重要组成部分。结论国内外胚胎干细胞相关信息的分析表明,目前我国在胚胎干细胞研究申请专利方面相对比较宽松,我们应该在涉及胚胎干细胞的分离、建系、在基因工程及细胞组织工程学方面的用途和方法以及胚胎干细胞在药物筛选过程中的用途等方面集中投入力量,争取有新的突破。     

Socioeconomic Characteristics and Trends in the Consumption of Ultra-Processed Foods in Korea from 2010 to 2018

There is growing evidence for a global transition to a more highly processed diet. While the dietary share of ultra-processed foods depends on a country’s economic status, food choice and consumption are also influenced by the socioeconomic situation of individuals. This study investigated whether ultra-processed food consumption differed across socioeconomic subgroups and over time (2010–2018) in Korea. Cross-sectional data from the Korea National Health and Nutrition Examination Survey 2010–2018 were analyzed. Food and beverages reported in a one-day 24 h recall were classified according to the NOVA food classification criteria. The dietary energy contribution of ultra-processed foods was high among men and urban residents, and increased with education and income level; additionally, it reached its peak in adolescents and thereafter decreased with increasing age. After adjusting the socioeconomic variables, such associations remained significant, except for income level. The overall contribution of ultra-processed foods increased from 23.1% (2010–2012) to 26.1% (2016–2018), and the same trend over time was observed in all age groups and socioeconomic strata. In the Korean population, ultra-processed food consumption differed by individual socioeconomic characteristics, but gradually increased over time, and this trend was consistently found in all socioeconomic subgroups. Future strategies to promote healthy food choices are needed for the Korean population.     

Trends in recent waterborne and foodborne disease outbreaks in South Korea, 2015–2019

ObjectivesThis study analyzed trends in foodborne and waterborne diseases in South Korea between 2015 and 2019.MethodsThe data consisted of information on outbreaks of waterborne and foodborne infectious diseases reported through the Korea Centers for Disease Control and Prevention (KCDC) system. We analyzed the trends and epidemiological aspects of outbreaks by month, place of occurrence, and causative pathogens in this observational study.ResultsThe number of outbreaks has steadily increased over the last 5 years, but the number of cases per outbreak has followed a decreasing trend. Incidence at daycare centers and preschools has been steadily increasing over consecutive years.ConclusionThe steady number of patients and decreasing number of cases per outbreak, even as the number of outbreaks has been increasing, suggest that the KCDC’s professional management system is operating effectively. It is necessary to continue improving the objectivity and efficiency of the management system and to carefully examine the increasing number of outbreaks in smaller-scale group catering facilities, such as daycare centers and preschools. Outbreaks can be prevented by closely examining those caused by unidentified pathogens and group outbreaks caused by other diseases, identifying problems, and supplementing the management system.     

The politics and ethics of human embryo and stem cell research.

There is great promise for stem cell research to develop cells and tissues for transplantation and treatment of diseases such as Alzheimer and Parkinson disease, diabetes, and heart problems. There is also promise to advance understanding and treatment of cancer and congenital defects. Human embryo research is fundamentally the only way to understand human fertilization, implantation, and early development. For years, federal funding of human embryo research has been held hostage to a congressional prolife agenda. Any reasonable solution to these political disputes that so greatly affect women's reproductive interests and the promise of health benefits from embryo and stem cell research should mandate that governmental sponsorship proceed.