BMPRⅡ^(+)neural precursor cells isolated and characterized from organotypic neurospheres:an in vitro model of human fetal spinal cord development

Roof plate secretion of bone morphogenetic proteins(BMPs)directs the cellular fate of sensory neurons during spinal cord development,including the formation of the ascending sensory columns,though their biology is not well understood.Type-ⅡBMP receptor(BMPRⅡ),the cognate receptor,is expressed by neural precursor cells during embryogenesis;however,an in vitro method of enriching BMPRⅡ^(+)human neural precursor cells(hNPCs)from the fetal spinal cord is absent.Immunofluorescence was undertaken on intact second-trimester human fetal spinal cord using antibodies to BMPRⅡand leukemia inhibitory factor(LIF).Regions of highest BMPRⅡ^(+)immunofluorescence localized to sensory columns.Parenchymal and meningeal-associated BMPRⅡ^(+)vascular cells were identified in both intact fetal spinal cord and cortex by co-positivity with vascular lineage markers,CD34/CD39.LIF immunostaining identified a population of somas concentrated in dorsal and ventral horn interneurons,mirroring the expression of LIF receptor/CD118.A combination of LIF supplementation and high-density culture maintained culture growth beyond 10 passages,while synergistically increasing the proportion of neurospheres with a stratified,cytoarchitecture.These neurospheres were characterized by BMPRⅡ^(+)/MAP2ab^(+/–)/βⅢ-tubulin^(+)/nestin^(–)/vimentin^(–)/GFAP^(–)/NeuN^(–)surface hNPCs surrounding a heterogeneous core ofβⅢ-tubulin^(+)/nestin^(+)/vimentin^(+)/GFAP^(+)/MAP2ab^(–)/NeuN^(–)multipotent precursors.Dissociated cultures from tripotential neurospheres contained neuronal(βⅢ-tubulin^(+)),astrocytic(GFAP+),and oligodendrocytic(O4+)lineage cells.Fluorescence-activated cell sorting-sorted BMPRⅡ^(+)hNPCs were MAP2ab^(+/–)/βⅢ-tubulin^(+)/GFAP^(–)/O4^(–)in culture.This is the first isolation of BMPRⅡ^(+)hNPCs identified and characterized in human fetal spinal cords.Our data show that LIF combines synergistically with high-density reaggregate cultures to support the organotypic reorganization of neurospheres,characterized by surface BMPRⅡ^(+)hNPCs.Our study has provided a new methodology for an in vitro model capable of amplifying human fetal spinal cord cell numbers for>10 passages.Investigations of the role BMPRⅡplays in spinal cord development have primarily relied upon mouse and rat models,with interpolations to human development being derived through inference.Because of significant species differences between murine biology and human,including anatomical dissimilarities in central nervous system(CNS)structure,the findings made in murine models cannot be presumed to apply to human spinal cord development.For these reasons,our human in vitro model offers a novel tool to better understand neurodevelopmental pathways,including BMP signaling,as well as spinal cord injury research and testing drug therapies.

The Impact of Human Resource Management on University Development

As competition in the education industry intensifies and the knowledge economy evolves,the significance of Human Resource Management(HRM)in university institutions.This study aims to explore how HRM affects the sustainable development and competitiveness improvement of universities.This article begins with a theoretical analysis to define the concept of HRM and its particular relevance within university education.The subsequent analysis examines the multi-dimensional framework of university development,encompassing its connotation,goals,and key influencing factors.The article further elaborates on the positive effects of HRM on university teaching quality,scientific research capabilities,organizational culture,and social services.On this basis,the main challenges currently faced by university HRM are discussed,such as talent mobility,institutional constraints,resource limitations,and internationalization pressure.Finally,optimization strategies are proposed,including building a scientific human resources system,enhancing talent training and development,fostering diversity among teaching staff,and improving decision-making efficiency and transparency.The conclusions of this study aim to provide strategic insights for university education managers to better utilize human resource advantages and promote the comprehensive and sustainable development of universities.

The generation and properties of human cortical organoids as a disease model for malformations of cortical development

As three-dimensional“organ-like”aggregates,human cortical organoids have emerged as powerful models for studying human brain evolution and brain disorders with unique advantages of humanspecificity,fidelity and manipulation.Human cortical organoids derived from human pluripotent stem cells can elaborately replicate many of the key properties of human cortical development at the molecular,cellular,structural,and functional levels,including the anatomy,functional neural network,and interaction among different brain regions,thus facilitating the discovery of brain development and evolution.In addition to studying the neuro-electrophysiological features of brain cortex development,human cortical organoids have been widely used to mimic the pathophysiological features of cortical-related disease,especially in mimicking malformations of cortical development,thus revealing pathological mechanism and identifying effective drugs.In this review,we provide an overview of the generation of human cortical organoids and the properties of recapitulated cortical development and further outline their applications in modeling malformations of cortical development including pathological phenotype,underlying mechanisms and rescue strategies.

Leveraging Robust Artificial Intelligence for Mechatronic Product Development—A Literature Review

Mechatronic product development is a complex and multidisciplinary field that encompasses various domains, including, among others, mechanical engineering, electrical engineering, control theory and software engineering. The integration of artificial intelligence technologies is revolutionizing this domain, offering opportunities to enhance design processes, optimize performance, and leverage vast amounts of knowledge. However, human expertise remains essential in contextualizing information, considering trade-offs, and ensuring ethical and societal implications are taken into account. This paper therefore explores the existing literature regarding the application of artificial intelligence as a comprehensive database, decision support system, and modeling tool in mechatronic product development. It analyzes the benefits of artificial intelligence in enabling domain linking, replacing human expert knowledge, improving prediction quality, and enhancing intelligent control systems. For this purpose, a consideration of the V-cycle takes place, a standard in mechatronic product development. Along this, an initial assessment of the AI potential is shown and important categories of AI support are formed. This is followed by an examination of the literature with regard to these aspects. As a result, the integration of artificial intelligence in mechatronic product development opens new possibilities and transforms the way innovative mechatronic systems are conceived, designed, and deployed. However, the approaches are only taking place selectively, and a holistic view of the development processes and the potential for robust and context-sensitive artificial intelligence along them is still needed.

Correlation between the Human Development Index and the Incidence and Mortality of Non-Hodgkin Lymphoma

Objective This study was to examine the relationship between socioeconomic status and the incidence and mortality of non-Hodgkin lymphoma(NHL).Methods We compared the age-standardized incidence rate(ASIR),age-standardized mortality rate(ASMR),and the ASMR to ASIR ratio(MIR)at national and regional levels and studied the correlation between the MIR and the human development index(HDI)in 2012 and 2018.Results The highest ASIR was in North America in 2012 and in Australia in 2018,and the lowest ASIR was in Central and South Asia in both 2012 and 2018.The highest ASMR was in North Africa in both 2012 and 2018,and the lowest ASMR was in Eastern Asia and South-Central Asia in 2012 and in South-Central Asia in 2018.The lowest MIR was in Australia in both 2012 and 2018,and the highest MIR was in Western Africa in both 2012 and 2018.HDI was strongly negatively correlated with MIR(r:−0.8810,P<0.0001,2012;r:−0.8895,P<0.0001,2018).Compared to the 2012 data,the MIR in the intermediate HDI countries significantly deceased and the HDI in low and high HDI countries significantly increased in 2018.Conclusion The MIR is negatively correlated with HDI.Increasing the HDI in low and intermediate HDI countries may reduce the MIR and increase the survival of patients with NHL.

Potential Impact of Space Environments on Developmental and Maturational Programs Which Evolved to Meet the Boundary Conditions of Earth: Will Maturing Humans Be Able to Establish a Functional Biologic System Set Point under Non-Earth Conditions?

Mammalian development and maturation, particularly processes for humans have evolved in the context of the boundary conditions of Earth (i.e. 1 g gravity, geomagnetic field, background radiation) to yield functional individuals, although the process is not perfect and “errors” do occur. With the advent of spaceflight to low Earth orbit (the International Space Station), humans are now exposed to microgravity and increased exposure to radiation. However, thus far, only adult humans have served as astronauts, but this will likely change with plans to explore deep space and colonize planets. Thus, conception, fetal development, post-birth maturation, puberty and skeletal maturity will occur in the context of boundary conditions that did not shape human evolution and influence physiological and biomechanical systems designed to function within the Earth’s boundary conditions. Thus, processes utilizing the 1 g environment (i.e. walking upright) and the geomagnetic field (i.e. the electrical/biomagnetic basis of neural interactions) will have to adapt to new boundary conditions, providing opportunity for additional errors or alterations in processing during development which could impact functional outcomes at multiple levels. This review/perspective will discuss some of these issues and attempt to provide direction for addressing the potential issues to be encountered.

On All-round Development of Human Rights in China

In October 2003, the Third Plenary Session of the Sixteenth Central Committee of the Communist Party of China （CPC） called for adherence to ＂the outlook toward development based on the fundamental interests of the people, toward an all-round, balanced and sustainable development.＂ The session also proposed to the National People＇s Congress （NPC） that respect for and protection of human rights be written into the country＇s Constitution. And accordingly, the NPC adopted a decision to revise the Constitution the following year. The call and the proposal were inter-related. The call sets the guideline, the theoretical basis and the orientation for the development of human rights in China. The pro- posal subsequently resulted in a revision of-the Constitution, the fundamental state law, which came as a legal guarantee for respect for and protection of human rights. Then, the ＂task of promoting an all-round development of the human rights cause＂ was written down into the country＇s Eleventh Five-Year Program for National Economic and Social Development （2006-2010）, which was approved by the NPC in March 2006. This was the first time that the development of human rights was written into a national program for social development. This means that an even closer link has been forged between China＇s human rights cause on one hand and the country＇s political, economic, cultural and social welfare undertakings on the other, thus preparing China＇s human rights cause for faster and sustainable development. We are now safe to predict that in the future, there will be even more and better rights the Chinese people are able to enjoy.

Artificial Intelligence and the Sustainable Development Goals: An Exploratory Study in the Context of the Society Domain

Artificial Intelligence (AI) experienced significant advancements in recent years, and its potential power is already recognized across various industries. Yet, the rise of AI has led to a growing concern about its impact on meeting the Sustainable Development Goals (SDGs). The aim of this paper was to evaluate contributions and the potential influence of AI to sustainable development in the society domain. Furthermore, the study analyzed GPT-3 responses, as one of the largest language models developed by OpenAI, descriptively. We conducted a set of queries on the SDGs to gather information on GPT-3’s perceptions of AI impact on sustainable development. Analysis of GPT-3’s contribution potential towards the SDGs showcased its broad range of capabilities for contributing to the SDGs in areas such as education, health, and communication. The study findings provide valuable insights into the contributions of AI to sustainable development in the society domain and highlight the importance of proper regulations to promote the responsible use of AI for sustainable development. We highlighted the potential for improvement in neural language processing skills of GPT-3 by avoiding imitating weak human writing styles with more mistakes in longer texts.

Impact of national Human Development Index on liver cancer outcomes: Transition from 2008 to 2018

BACKGROUND Liver cancer is the sixth most commonly diagnosed cancer and the fourth leading cause of cancer death worldwide.Socioeconomic development,indicated by the Human Development Index(HDI),is closely interconnected with public health.But the manner in which social development and medical advances influenced liver cancer patients in the past decade is still unknown.AIM To investigate the influence of HDI on clinical outcomes for patients with existing liver cancer from 2008 to 2018.METHODS The HDI values were obtained from the United Nations Development Programme,the age-standardized incidence and mortality rates of liver cancer were obtained from the GLOBOCAN database to calculate the mortality-toincidence ratio,and the estimated 5-year net survival of patients with liver cancer was provided by the CONCORD-3 program.We then explored the association of mortality-to-incidence ratio and survival with HDI,with a focus on geographic variability across countries as well as temporal heterogeneity over the past decade.RESULTS From 2008 to 2018,the epidemiology of liver cancer had changed across countries.Liver cancer mortality-to-incidence ratios were negatively correlated and showed good fit with a modified“dose-to-inhibition response”pattern with HDI(r=-0.548,P<0.0001 for 2018;r=-0.617,P<0.0001 for 2008).Cancer survival was positively associated with HDI(r=0.408,P<0.01)and negatively associated with mortality-to-incidence ratio(r=-0.346,P<0.05),solidly confirming the interrelation among liver cancer outcome indicators and socioeconomic factors.Notably,in the past decade,the HDI values in most countries have increased alongside a decreasing tendency of liver cancer mortality-to-incidence ratios(P<0.0001),and survival outcomes have simultaneously improved(P<0.001),with significant disparities across countries.CONCLUSION Socioeconomic factors have a significant influence on cancer outcomes.HDI values have increased along with improved cancer outcomes,with significant disparities among countries.

Human development index is associated with mortality-to-incidence ratios of gastrointestinal cancers

AIM:To identify the role of human development in the incidence and mortality rates of gastrointestinal cancers worldwide.METHODS:The age-standardized incidence and mortality rates for gastrointestinal cancers,including cancers of the esophagus,stomach,pancreas,liver,gallbladder,and colorectum,were obtained from the GLOBOCAN 2008 database and United States Cancer Statistics(USCS)report.The human development index(HDI)data were calculated according to the 2011 Human Development Report.We estimated the mortality-toincidence ratios(MIRs)at the regional and national levels,and explored the association of the MIR with development levels as measured by the HDI using a modified"drug dose to inhibition response"model.Furthermore,countries were divided into four groups according to the HDI distribution,and the MIRs of the four HDI groups were compared by one-way ANOVA followed by the Tukey-Kramer post-hoc test.Statespecific MIRs in the United States were predicted from the estimated HDI using the fitted non-linear model,and were compared with the actual MIRs calculated from data in the USCS report.RESULTS:The worldwide incidence and mortality rates of gastrointestinal cancers were as high as 39.4and 54.9 cases per 100000 individuals,respectively.Linear and non-linear regression analyses revealed an inverse correlation between the MIR of gastrointestinal cancers and the HDI at the regional and national levels(<0;P=0.0028 for regional level and<0.0001 for national level,ANOVA).The MIR differed significantly among the four HDI areas(very high HDI,0.620±0.033;high HDI,0.807±0.018;medium HDI,0.857±0.021;low HDI,0.953±0.011;P<0.001,oneway ANOVA).Prediction of the MIRs for individual United States states using best-fitted non-linear models showed little deviation from the actual MIRs in the United States.Except for 28 data points(9.93%of282),the actual MIRs of all gastrointestinal cancers were mostly located in the prediction intervals via the best-fit non-linear regression models.CONCLUSION:The inverse correlation between HDI and MIR demonstrates that more developed areas have a relatively efficacious healthcare system,resulting in low MIRs,and HDI can be used to estimate the MIR.

Cultivating New-type Farmers Based on the Theory of Human Resources Development

Under the direction of theory of human resources development,this thesis analyzes the impact of rural human resources development oncultivating new-type farmers.Firstly,it increases the input of rural basic education;secondly,it reinforces the vocational education and technologytraining;thirdly,it promotes the rural medical and public health services;fourthly,it quickens the rural labor transfer.The status quo of China's ruralhuman resources has been analyzed as follows:in terms of the quantity of rural human resources,the status quo is large and quick-developed baseof rural human resources,high labor participatory rate,and constitution of low age;in terms of the quality of rural human resources,the status quois the ubiquitous low quality of rural human resources,low technological level of rural human resources,and overall low physical quality of farmers;in terms of the structure of rural human resources,the status quo is the irrational industrial structure distribution and imbalanced regional structuredistribution.The thesis also discusses the edification of theory of human resources development in cultivating new-type farmers.First,in terms ofthe control over quantity of rural human resources,it is to keep the stability of family planning policy,and expedite the transfer of rural surplus la-bor;second,in terms of promoting the quality of rural human resources,it is to bolster the development of reserve rural labor force resources,toconstruct the adult educational training system with Chinese characteristics,and to build rural primary health care system;third,in terms of adjus-ting the structure of rural human resources,it is to perfect rural human resources market,and adjust rural economical structure and talents struc-ture.

Path Breakthrough of Medical Humanities Education From the Perspective of“All-Staff,Whole-Process,and All-Round Education”

Medical education is an important cornerstone for the development of healthcare,and medical humanities education,as an integral part of medical education,plays an irreplaceable role in cultivating people’s health guardians with high medical ethics.We adopted the method of stratified random sampling to select 309 students and 107 faculty members from three independent medical colleges in Sichuan province as the research subjects and distributed questionnaire surveys investigating in three dimensions:overall cognition of medical humanities,evaluation of medical humanistic qualities,and the current situation of medical humanities education,supplemented by an in-depth literature review and interviews with subject matter experts.We found that“tech-centrism”still has a great influence,the self-evaluation of medical students’humanistic quality is generally not high,the educational concept of“emphasizing professional skills over morality”of faculty and staff is still quite prevalent,and there is still the“last mile”phenomenon in medical humanities education.In order to promote the integrated development of“new medicine”and“new liberal arts”and break the barriers of“tech-centrism”and“instrumental rationality,”it is necessary to change the educational concept and strengthen the education of all employees,break through the bottleneck of internships and strengthen the whole process of education,integrate educational resources and strengthen all-round education,improve the incentive mechanisms,strengthen the assessment methods,and provide Chinese wisdom and Chinese solutions for the development of medical humanities education.

Organic carbon isotope and pollen evidence for mangrove development and response to human activity in Guangxi(Southwest China) over the last 140 years

Mangrove degradation must reduce carbon sequestration in recent years, thereby aggravating global warming.Thus, short-term impacts of human activity on mangrove ecosystems are cause for concern from local governments and scientists. Mangroves sediments can provide detailed records of mangrove species variation in the last one hundred years, based on detailed 210 Pb data. The study traced the history of mangrove development and its response to environmental change over the last 140 years in two mangrove swamps of Guangxi, Southwest China. Average sedimentation rates were calculated to be 0.48 cm/a and 0.56 cm/a in the Yingluo Bay and the Maowei Sea, respectively. Chemical indicators（δ13Corg and C：N） were utilized to trace the contribution of mangrove-derived organic matter（MOM） using a ternary mixing model. Simultaneous use of mangrove pollen can help to supplement some of these limitations in diagenetic/overlap of isotopic signatures. We found that vertical distribution of MOM was consistent with mangrove pollen, which could provide similar information for tracing mangrove ecosystems. Therefore, mangrove development was reconstructed and divided into three stages： flourishing, degradation and re-flourishing/re-degradation period. The significant degradation, found in the period of 1968–1998 and 1907–2007 in the Yingluo Bay and the Maowei Sea, respectively, corresponding to a rapid increase of reclamation area and seawall length, rather than climate change as recorded in the region.

Effects of cold climate on growth and development

Climate is one of the environmental conditions on which people live.Climate conditions impact every aspect of people's daily life and production activities,even the survival of humankind.In recent years,human activities have adversely changed the climate.The emergence of global warming and extreme weather has prompted people to pay attention to the impact of climate on life.The adverse climate issues include reduced quality of air and food,facilitated spread of diseases and increased mortality of the population.Being more orientated to climate changes in the past,research has been less alerted to the negative impacts that climate changes could bring to human health.This could be ascribed to that after living in a region for a long time,the human body has"adapted"to climate.And after adaptation,routine health outcomes such as disease incidence and hospitalization rate become less obvious,making the habitants blind from the undesirable impacts of climate on the health status.This review article summarizes the impacts of cold climate on human development,including maternal/fetal factors,lifestyle factors,etc.,and delineates the relationship between cold climate and human health.

A Multi-Level Evaluation of Policy Integration of Human Resource Development in Agriculture Sector

Human resource development assumes as a golden key for a knowledge-based economy and competitiveness. This study evaluates policy integration of human resource development (HRD) in agricultural sector within the context of multi-level governance (i.e., interdependence of administrative levels in decision making) and suggests means to enhance policy integration in Bangladesh. Conducting a critical review of major policy instruments, key informant interview and two case studies, this study concluded that HRD issue has fairly included and observed consistency (between the aim of HRD and policy) in all policies and strategies;majority of policy instruments have significantly addressed the significance of HRD and added plans for its development;reporting, monitoring and evaluation of policies and strategies are rather weak and there is no adequate flow of financial arrangement that is largely determined by the availability of government project. Based on the findings, the following means should be useful for improving HRD policy integration such as providing a handsome amount of development budget at the sub-district agricultural office, formulating coherent strategies to build effective cooperation, coordination and participation among stakeholders, initiating special capacity building programmes for rural women, young farmers and smallholders and mainstreaming HRD issue in governmental planning and programmes, and accordingly crafting policies and implementation.

Exploring Green Development From the Perspective of Sociology:Logical Basis,Constraints,and Optimization Paths

With the advancement of ecological conservation in China,the concept of green development has gained extensive acceptance and recognition.Exploring green development from the perspectives of environmental protection and sociology holds great theoretical value and practical significance in studying the issues related to green development.Firstly,this paper examines green development in light of the objective needs of the economic and social transformation in the international community and China,and deconstructed its underlying social logic.Secondly,it further investigates the social factors that restrict green development,encompassing social structures,social concepts,social systems,and social behaviors.Finally,within the framework of the“green”discipline system in environmental sociology,this paper proposes specific measures such as restructuring social systems and transforming production modes,lifestyles,and consumption patterns to promote green development.

Human Rights Connotations and Its Legal Protection in the Harmonious Coexistence between Humans and Nature

Promoting the unity of human nature and sociality in practice is a fundamental path dependence for achieving people's well-rounded development.Within the context of harmonious coexistence between humans and nature,the practice of the unity of human nature and sociality is allowed to be truly implemented,and people's well-rounded development moves from possibility to reality.Strengthening the protection of human rights for people's well-rounded development in the harmonious coexistence between humans and nature not only requires the expansion of the connotations of environmental rights from“the right to a healthy environment”to“the right to a beautiful environment”,but also necessitates the formation of a collaborative framework between environmental rights and development rights.For legal responses to the expansion of the connotations of environmental rights,it is necessary to implement such expansions in environmental legislation,enhance the underlying principles,and make progress in the development of systematic environmental legislation simultaneously.Regarding the legal promotion of the synergy between environmental rights and development rights,it is essential to follow the guidance of the“Two Mountains Theory,”take the coordinated functions of environmental and traditional legal departments as the basis,and build a legal mechanism for the realization of the value of ecological products and services.

The Relationship between Human Rights and Development——A Brief Analysis of the Perspectives of Chinese Scholars and the Practice of Chinese Government

With the change and development of the concept of human rights, the thinking about the relationship between human rights and development is becoming more and more deeply. Under this background, the author profoundly realizes that both recognizing the economic development as the first priority like some developing countries do and considering the human rights to be the most important thing as most developed countries do are unilateral and harmful to the social progress. Human rights and development are interdependent and mutually promoting each other. This paper introduces the three main viewpoints of the relationship between human rights and development. Based on the changes of the attitudes of the UN and China to the relationship between human rights and development, this paper holds that though it is a great progress for the Chinese government to understand that human rights and development are interdependent, there are still lots of difficulties in realizing their mutually benefiting relationship in reality. These difficulties are due to the lack of professionals who enjoy good understandings of the rules for social development and are capable of practicing human rights theories. Therefore, the authors suggest that the promotion of human rights education is instrumental to the development and progress of human society.

Human pluripotent stem cell-derived kidney organoids:Current progress and challenges

Human pluripotent stem cell(hPSC)-derived kidney organoids share similarities with the fetal kidney.However,the current hPSC-derived kidney organoids have some limitations,including the inability to perform nephrogenesis and lack of a corticomedullary definition,uniform vascular system,and coordinated exit path-way for urinary filtrate.Therefore,further studies are required to produce hPSC-derived kidney organoids that accurately mimic human kidneys to facilitate research on kidney development,regeneration,disease modeling,and drug screening.In this review,we discussed recent advances in the generation of hPSC-derived kidney organoids,how these organoids contribute to the understanding of human kidney development and research in disease modeling.Additionally,the limitations,future research focus,and applications of hPSC-derived kidney organoids were highlighted.

Location and expression of neurotrophin-3 and its receptor in the brain of human embryos during early development

BACKGROUND： Cell culture in vitro trials have demonstrated that neurotrophin-3 （NT-3） can enhance the survival of sensory neurons and sympathetic neurons, and can also support embryo-derived motor neurons. This effect is dependent on nerve growth factor on the surface of cells. Understanding the role of NT-3 and its receptor in the early development of human embryonic brains will help to investigate the correlation between early survival of nerve cells and the microenvironment of neural regeneration. OBJECTIVE： To observe the proliferation of cerebral neurons in the development of human embryonic brain, and to investigate the location, expression and distribution of NT-3 and its receptor TrkC during human brain development. DESIGN, TIME AND SETTING： An observation study on cells was performed in the Department of ttuman Anatomy, Histology and Embryology, Chengdu Medical College in September 2007. MATERIALS： Fifteen specimens of flesh human embryo, aged 6 weeks, were used in this study. METHODS： The proliferation of cerebral neurons was detected using proliferating cell nuclear antigen, and the immunocytochemistry ABC technique was applied to observe the location, expression and distribution of NT-3 and its receptor TrkC in the brain of the human embryo. MAIN OUTCOME MEASURES： Location, expression and distribution of NT-3 and its receptor in the brain of the human embryo. RESULTS： In the early period （aged 6 weeks） of human embryonic development, proliferating cell nuclear antigen-positive reactive substances were mainly observed in the nucleus of the forebrain ventricular zone and subventricular zone, and the intensity was stronger in the subventricular zone than the forebrain ventricle. NT-3 positive reactive substance was mainly distributed in the cytoblastema of the forebrain neuroepithelial layer and nerve cell process, while TrkC was mainly distributed in the cell membrane of the forebrain ventricular zone and subventricular zone. During embryonic development, NT-3 and TrkC showed a positive immune reaction to a greater or lesser extent in ependymal epithelium. CONCLUSION： During early human embryonic development, cerebral nerve cells proliferate in the ventricular zone and subventricular zone, and NT-3 is expressed in the neural axon. The results show that the highly expressed NT-3 could promote the proliferation of neural axons and maintain the neuron body＇s survival.