One-step cell biomanufacturing platform:porous gelatin microcarrier beads promote human embryonic stem cell-derived midbrain dopaminergic progenitor cell differentiation in vitro and survival after transplantation in vivo

Numerous studies have shown that cell replacement therapy can replenish lost cells and rebuild neural circuitry in animal models of Parkinson’s disease.Transplantation of midbrain dopaminergic progenitor cells is a promising treatment for Parkinson’s disease.However,transplanted cells can be injured by mechanical damage during handling and by changes in the transplantation niche.Here,we developed a one-step biomanufacturing platform that uses small-aperture gelatin microcarriers to produce beads carrying midbrain dopaminergic progenitor cells.These beads allow midbrain dopaminergic progenitor cell differentiation and cryopreservation without digestion,effectively maintaining axonal integrity in vitro.Importantly,midbrain dopaminergic progenitor cell bead grafts showed increased survival and only mild immunoreactivity in vivo compared with suspended midbrain dopaminergic progenitor cell grafts.Overall,our findings show that these midbrain dopaminergic progenitor cell beads enhance the effectiveness of neuronal cell transplantation.

Pioneering a New Realm of Human Rights Civilization in the Chinese Path to Modernization——An Overview of the Symposium on“The Chinese Path to Modernization and the Promotion of Free and Comprehensive Human Development”

On October 14,2023,a symposium themed“The Chinese Path to Modernization and the Promotion of Free and Comprehensive Human Development”was held in Changchun,Jilin Province,China.More than fifty experts,scholars,and researchers from national institutions and universities engaged in discussions and exchanges on human rights on the Chinese path to modernization,including the path,practice,knowledge systems,and civilization forms of human rights.This symposium played a significant role in advancing the construction of the disciplinary system,academic system,and discourse system of human rights in China.

Contamination and human health risk assessment of heavy metal(loid)s in topsoil and groundwater around mining and dressing factories in Chifeng,North China

Chifeng is a concentrated mining area for non-ferrous metal minerals,as well as a key prevention and control area for heavyduty enterprises.This situation necessitates an efective ecological and human health risk assessment of heavy metal(loid)s driven by the wide distribution of metal ore processing,mining,and smelting factories in Hexigten Banner and Bairin Left Banner.We conducted surveys to assess the levels of heavy metal(loid)s(Cr,As,Pb,Cd,and Hg)in the topsoil and groundwater of the areas.The results indicated that the concentrations of As,Cd,and Pb in partial soil samples exceeded the environmental quality standards of Grade II.Based on contamination assessments,such as geoaccumulation indices and pollution indices,we inferred that Cd,Pb,and As were primary pollutants in topsoil.Potential ecological risks when considered as part of the average risk indices(RI)are up to 1626.40 and 2818.76,respectively,in the two areas.Comparative analysis revealed that Cd posed a very high potential ecological risk,followed by As.Moreover,the evaluation showed that the three exposure pathways of carcinogenic and non-carcinogenic risk followed a descending order:inhalation>ingestion>dermal contact,except for Pb.Arsenic in topsoil posed a potential non-carcinogenic risk to human health,while there were no adverse efects of As in groundwater.In addition,the average total carcinogenic risk for As in the two areas,as well as the risk of Pb in the topsoil of Bairin Left Banner and all the fve heavy metal(loid)s in groundwater,exceeded human tolerance.Pb–Zn mines caused higher human health risks.In addition,the tandem contamination of heavy metal(loid)s in soil and groundwater was not obvious.This research study provides a basis for pollution remediation to control heavy industry-induced ecological and health risks of heavy metal(loid)s.

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.

Crohn’s disease in human immunodeficiency virus-infected patient:A case report

BACKGROUND Inflammatory bowel disease(IBD)is an autoimmune condition treated with immunosuppressive drugs.However,the need for immune system suppression becomes questionable when infection with the human immunodeficiency virus(HIV)occurs simultaneously and impacts the course of IBD.Our reported case represents the clinical course,prescribed treatment and its effect,as well as clinical challenges faced by physicians in a combination of such diseases.We also present a comprehensive literature review of similar cases.CASE SUMMARY A 49-year-old woman suffering from a newly diagnosed Crohn’s disease was hospitalized due to exacerbated symptoms(abdominal pain,fever,and weight loss).During her hospital stay,she tested positive for HIV.With conservative treatment,the patient improved and was discharged.In the outpatient clinic,her HIV infection was confirmed as stage C3,and antiretroviral treatment was initiated immediately.That notwithstanding,soon the patient was rehospitalized with pulmonary embolism and developed a series of complications because of the subsequent coexistence of IBD and HIV.After intensive and meticulous treatment,the patient’s condition has improved and she remains in remission.CONCLUSION The paucity of studies and data on the coexistence of HIV and IBD leaves clinicians doubting the optimal treatment options.

Constructing China’s Human Rights Science:Cause,Cognition,and Paradigm

“China’s Human Rights Science”is undoubtedly a brand-new concept.Just as China has its own philosophy,literature,history,law,political science,and sociology,it should also have its own human rights science.China’s Human Rights Science refers to the cognitive science of human rights in China.Developing its disciplinary system,academic system,and discourse system,and constructing an independent Chinese human rights knowledge system,are essential requirements for promoting the great rejuvenation of the Chinese nation through Chinese modernization and creating a new form of human civilization.China’s Human Rights Science originated in China,grew in China,and deepened through China’s human rights practices.China’s Human Rights Science adhere to the universality of human rights principles and possess distinctive characteristics.It works as the knowledge-based organization,academic refinement,and theoretical expression of the path of human rights development that conforms to the trend of the times and suits China’s national conditions,as pursued by the Communist Party of China in leading the people.China’s Human Rights Science can enrich and develop the theory of human rights civilization,and should become a global public product of human rights.

Effect of Human Umbilical Cord Mesenchymal Stem Cells on GRP78/ATF4 Pathway in Alzheimer s Disease Model Mice

[Objectives]To study the effect of human umbilical cord mesenchymal stem cells(hUC-MSCs)on GRP78/ATF4 pathway in APP/PS1 mice.[Methods]Twelve 6-month-old female APP/PS1 mice were randomly divided into model group(MOD,n=6)and human umbilical cord mesenchymal stem cell treatment group(MSC,n=6);six 6-month-old C57BL/6N mice were used as control group(CON,n=6).The mice in each group were treated with the fourth generation of human umbilical cord mesenchymal stem cells through tail vein.Four weeks later,the mice in each group were killed.The expression of GFP78 and ATF4 in the cortex of mice in each group was detected by Western blotting and real-time fluorescence quantitative PCR.[Results]The results of immunoblotting and real-time fluorescence quantitative PCR showed that the expression of GRP78 in MOD group was lower than that in CON group and the expression of ATF4 increased.The expression of GRP78 protein in MSC group was higher than that in MOD group,but the expression of ATF4 protein was lower.The results of real-time fluorescence quantitative PCR showed that the mRNA level of GRP78 decreased and the mRNA level of ATF4 increased in MOD group compared with CON group.The mRNA level of GRP78 in MSC group was higher than that in MOD group,while the mRNA level of ATF4 in MSC group was lower than that in MOD group.[Conclusions]Human umbilical cord mesenchymal stem cells can regulate the expression of GRP78/ATF4 pathway in APP/PSI mice,which may be related to the stress level of endoplasmic reticulum in the brain of APP/PS1 mice mediated by human umbilical cord mesenchymal stem cells.

The Core of the Chinese Democracy Is to Respect and Protect Human Rights——A Summary of the Academic Seminar on Chinese Democracy and Human Rights Protection

On March 26,2023,a Seminar on Chinese Democracy and Human Rights Protection was held,jointly organized by the National Human Rights Education and Training Base and the Human Rights Research Center of Central South University under the guidance of the Chinese Society for Human Rights Studies.The event adopted a combination of online and offline channels.Over 30 experts and scholars from universities,research institutions,and practical departments across the country participated in extensive discussions on“Theoretical and Practical Aspects of Chinese Democracy and Protection of Human Rights.”The seminar aimed to focused on the essence,characteristics,advantages,and human rights implications of Chinese democracy and interpreted the concept of Chinese democracy and the protection of human rights through academic and theoretical methods.

Human Rights in China:Exploration and Development of Whole-process People’s Democracy

Whole-process people’s democracy represents a new exploration of socialism with Chinese characteristics for a new era as well as a novel and important method for protecting the human rights of the Chinese people.It is conducive to solving a multitude of problems hindering the protection of civil rights and political rights.The greatest highlight of whole-process people’s democracy is that the people are the masters of their own country and exercise the power to govern the state through“extensive participation and consultation.”China’s experience and approaches in advancing whole-process people’s democracy provide a reference for other countries.

Rebuilding insight into the pathophysiology of Alzheimer’s disease through new blood-brain barrier models

The blood-brain barrier is a unique function of the microvasculature in the brain parenchyma that maintains homeostasis in the central nervous system.Blood-brain barrier breakdown is a common pathology in various neurological diseases,such as Alzheimer’s disease,stroke,multiple sclerosis,and Parkinson’s disease.Traditionally,it has been considered a consequence of neuroinflammation or neurodegeneration,but recent advanced imaging techniques and detailed studies in animal models show that blood-brain barrier breakdown occurs early in the disease process and may precede neuronal loss.Thus,the blood-brain barrier is attractive as a potential therapeutic target for neurological diseases that lack effective therapeutics.To elucidate the molecular mechanism underlying blood-brain barrier breakdown and translate them into therapeutic strategies for neurological diseases,there is a growing demand for experimental models of human origin that allow for functional assessments.Recently,several human induced pluripotent stem cell-derived blood-brain barrier models have been established and various in vitro blood-brain barrier models using microdevices have been proposed.Especially in the Alzheimer’s disease field,the human evidence for blood-brain barrier dysfunction has been demonstrated and human induced pluripotent stem cell-derived blood-brain barrier models have suggested the putative molecular mechanisms of pathological blood-brain barrier.In this review,we summarize recent evidence of blood-brain barrier dysfunction in Alzheimer’s disease from pathological analyses,imaging studies,animal models,and stem cell sources.Additionally,we discuss the potential future directions for blood-brain barrier research.

重组人糖蛋白激素β5/α2融合蛋白在CHO-S细胞中的表达纯化及功能活性分析

目的在悬浮中国仓鼠卵巢细胞(Chinese hamster ovary cells,CHO-S)中分泌表达、纯化重组hCGH-CTP融合蛋白,验证其对3T3-L1成熟脂肪细胞脂质积累的影响。方法构建CTP连接肽融合人糖蛋白激素β5/α2重组蛋白表达载体pcDNA3.1-rhCGH-CTP,将其瞬时转染CHO-S悬浮细胞中,大量表达纯化并验证rhCGH-CTP蛋白生物学活性;通过干预3T3-L1成熟脂肪细胞24 h,观察细胞内甘油三酯(TG)水平的变化。结果Western blot结果显示,rhCGH-CTP蛋白在CHO-S细胞中成功表达,表达量可达715.4 mg·L^(-1);用AKTA pure蛋白纯化系统纯化蛋白,SDS-PAGE方法鉴定纯化出的蛋白纯度较高可达90%。此外,在高表达TSHR基因的成熟脂肪细胞3T3-L1中,利用ELISA试剂盒测定不同浓度rhCGH-CTP蛋白干预后胞内cAMP含量明显升高,说明rhCGH-CTP蛋白具有生物活性;油红O染色结果发现,与对照组相比,不同浓度rhCGH-CTP蛋白干预组的成熟脂肪细胞中TG含量明显降低(P<0.05)。结论成功表达并纯化了rhCGH-CTP融合蛋白,其具有良好的生物学活性并能有效降低TG,该研究为后续深入揭示CGH蛋白的生理作用及在临床实践中的潜在应用提供了重要基础。

The Alzheimer’s Dementia Patients’ Observed Illness Course and Experience in Ghana and Care Lessons to Be Learnt: A Mental Health Professional’s Perspective

Alzheimer’s disease (AD) and associated dementia patient numbers continue to increase globally with associated economic costs to healthcare systems. Of note is the increase in numbers in lower and middle-income countries (LMICs) including Sub-Saharan African (SSA) countries, which already face challenges with their health budgets from communicable and non-communicable diseases. Ghana, an SSA country, faces the problem of healthcare budgetary difficulties and the additional impact of AD as a consequence of increasing population strata of old aged persons (OAPs) due to the demographic transition effect. This article uses examples of known patients’ illness courses to give a perspective on the lived experience of patients with dementia (PWD) in Ghana, living amongst a populace with a culture of stigmatization of PWD, and a relatively fragile public mental health system (PMHS) for those with mental illness, including AD. The lived experience of AD patients is characterised by stigmatisation, discrimination, non-inclusiveness, diminished dignity and human rights abuses in the face of their mental disability, and eventually death. This article is an advocacy article giving voice to the voiceless and all persons suffering from AD and other dementias in Ghana, whilst pleading for a call to action from healthcare professionals and responsible state agencies.

观察基于Watson人性照顾理论的干预对重症肺炎合并呼吸衰竭患者的应用效果

目的:观察基于Watson人性照顾理论的干预对重症肺炎合并呼吸衰竭患者的应用效果。方法:选取2021年6月至2023年6月泉州市第一医院呼吸与危重症医学科收治的重症肺炎合并呼吸衰竭患者94例作为研究对象,按照随机数字表法分为对照组和观察组,每组47例。对照组给予常规护理干预,观察组在对照组基础上给予Watson人性照顾理论的干预。采用匹兹堡睡眠质量指数量表(PSQI)比较2组患者干预前后睡眠质量的变化,采用阿森斯失眠量表(AIS)评估2组患者干预前后失眠的改善效果,并通过2组患者护理后的呼吸困难缓解时间、机械通气时间、重症监护室住院时间,以判断恢复情况。结果:干预后,观察组患者PSQI评分、AIS评分均显著低于对照组,观察组呼吸困难缓解时间、机械通气时间及重症监护室住院时间均显著短于对照组,差异均有统计学意义(均P<0.05)。结论:对重症肺炎合并呼吸衰竭患者应用基于Watson人性照顾理论的护理干预可有效改善其睡眠质量,促进病情恢复,值得临床推广应用。

Gut microbiota in preterm infants receiving breast milk or mixed feeding

BACKGROUND Preterm birth is the leading cause of mortality in newborns,with very-low-birthweight infants usually experiencing several complications.Breast milk is considered the gold standard of nutrition,especially for preterm infants with delayed gut colonization,because it contains beneficial microorganisms,such as Lactobacilli and Bifidobacteria.AIM To analyze the gut microbiota of breastfed preterm infants with a birth weight of 1500 g or less.METHODS An observational study was performed on preterm infants with up to 36.6 wk of gestation and a birth weight of 1500 g or less,born at the University Hospital Dr.JoséEleuterio González at Monterrey,Mexico.A total of 40 preterm neonates were classified into breast milk feeding(BM)and mixed feeding(MF)groups(21 in the BM group and 19 in the MF group),from October 2017 to June 2019.Fecal samples were collected before they were introduced to any feeding type.After full enteral feeding was achieved,the composition of the gut microbiota was analyzed using 16S rRNA gene sequencing.Numerical variables were compared using Student’s t-test or using the Mann–Whitney U test for nonparametric variables.Dominance,evenness,equitability,Margalef’s index,Fisher’s alpha,Chao-1 index,and Shannon’s diversity index were also calculated.RESULTS No significant differences were observed at the genus level between the groups.Class comparison indicated higher counts of Alphaproteobacteria and Betaproteobacteria in the initial compared to the final sample of the BM group(P<0.011).In addition,higher counts of Gammaproteobacteria were detected in the final than in the initial sample(P=0.040).According to the Margalef index,Fisher’s alpha,and Chao-1 index,a decrease in species richness from the initial to the final sample,regardless of the feeding type,was observed(P<0.050).The four predominant phyla were Bacteroidetes,Actinobacteria,Firmicutes,and Proteobacteria,with Proteobacteria being the most abundant.However,no significant differences were observed between the initial and final samples at the phylum level.CONCLUSION Breastfeeding is associated with a decrease in Alphaproteobacteria and Betaproteobacteria and an increase of Gammaproteobacteria,contributing to the literature of the gut microbiota structure of very low-birth-weight,preterm.

人尿激肽原酶对SAMP8小鼠模型认知功能的影响及机制

目的研究人尿激肽原酶(human urinary kallidinogenase,HUK)对SAMP8小鼠模型认知功能的影响及机制。方法SAMP8鼠分为5组:SAMP8组、治疗组(分别给予8.75×10^(-3)、1.75×10^(-2)、3.5×10^(-2)、7.0×10^(-2)PNAU·kg^(-1) HUK),并以SAMR1溶媒组作为空白对照。各组行Morris水迷宫检测空间认知水平,选取认知改善最明显一组(HUK组)进行后续实验。免疫组化检测CA3区ChAT表达情况,以RT-PCR进一步验证。Western blot检测PSD95、SYN、BDNF、pCREB蛋白表达。测定MPO活性及IL-1β、IL-18含量。结果SAMP8组小鼠的平台穿梭次数较SAMR1组减少(P<0.05),给予不同剂量HUK后,平台穿梭次数较SAMP8组增多(P<0.05或P<0.01),目的象限探索时间短(P<0.05或P<0.01),我们以7.0×10^(-2)PNAU·kg^(-1)剂量组(HUK组)进行后续实验。SAMP8组CA3区ChAT阳性细胞较SAMR1组表达明显减少;HUK组阳性细胞表达明显增多;RtPCR显示ChAT在SAMP8组表达明显低于SAMR1组,给予HUK治疗后ChAT表达明显高于SAMP8组。与SAMR1组比较,SAMP8组CA3区中IL-1β、IL-18含量、MPO活性明显升高,PSD95、SYN、BNDF和pCREB蛋白表达降低。经HUK干预后,IL-1β、IL-18含量及MPO活性降低,PSD95、SYN、BNDF和pCREB蛋白表达均增加。结论HUK改善SAMP8小鼠的空间认知功能,其机制可能是通过促进CA3区ChAT表达、减轻氧化应激水平及增加突触相关蛋白表达来实现。

Genotypic analysis on the ORF-K1 gene of human herpesvirus 8 from patients with Kaposi's sarcoma in Xinjiang,China

Human herpesvirus 8 （HHV-8） is thought to be essential for the development of all forms of Kaposi＇s sarcoma （KS）. HHV-8 DNA is present virtually in all KS tumor biopsy samples. Genes at both ends of the HHV-8 genome have been shown to vary considerably. Seven major molecular subtypes of HHV-8 were defined based on the amino acid sequence of the open reading frame K1 （ORF-K1）, generally known as A, B, C, D, E, F, and Z. Most strains collected worldwide were clustered into two subtypes （A and C）. Here, the K1/VRI region of HHV-8 was amplified by nested PCR in 22 （81.48%） of 27 cases from Xinjiang Uygur Autonomous Region, a province in northwestern China. Phylogenetic analysis on the basis of the K1/VR1 amino acid sequence indicated that the majority of these KS patients were infected by subtype C HHV-8 （n = 18, including 15 belonging to the C2 group）, and several by subtype A （n = 4, including 3 being the A1 group）. This is the first report of subtype A HHV-8 in China. Furthermore, the correlations between different forms and lesions of KS and different subtypes of HHV-8 were analyzed. The findings showed that subtype A HHV-8 resulted in significantly more frequent mucosal KS lesions than subtype C. However, there was no obvious correlation between different forms of KS and different subtypes of HHV-8.

Monoamine alterations and rotational asymmetry in a rat model of Parkinson's disease following lateral ventricle transplantation of human amniotic epithelial cells

BACKGROUND： Human amniotic epithelial cells （HAECs） can differentiate into neurons, astrocytes and oligodendrocytes. They biologically secrete many active neurotrophins and have the capacity to metabolize dopamine enzymes. These features underlie a theoretical basis for the treatment of Parkinson＇s disease （PD）. OBJECTIVE： To investigate the survival and differentiation of transplanted HAECs in the lateral ventricle of PD model rats, and to explore its effect on circling behavior, as well as levels of dopamine （DA）, the metabolite homovanillic acid, dihydroxyphenyl acetic acid, 5-hydroxyindoleacetic acid, and 5-hydroxytryptamine in the striatum. DESIGN, TIME AND SETTING： A randomized, controlled, animal study was performed at the Institute of Biochemistry and Cell Biology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, and Shanghai Celstar Institute of Biotechnology from May 2007 to December 2008. MATERIALS： HAECs were derived from the placental chorion following caesarean delivery at the Shanghai International Matemal and Child Health Hospital. 6-hydroxydopamine （6-OHDA）, and mouse anti-human Vimentin monoclonal antibody were purchased from Sigma, USA; mouse anti-human nestin and tyrosine hydroxylase （TH） monoclonal antibodies were purchased from Chemicon, USA. METHODS： A total of 114 healthy, adult, Sprague Dawley rats were randomly assigned to two groups： PD model [n = 90, stereotactic microinjection of 2 μL 6-OHDA （3.5 μg/uL） into the striatum] and control （n = 24, no treatment）. The 51 successful PD model rats were randomly divided into 3 subgroups （n = 17）： HAEC, PBS, and model. The HAEC and PBS groups were respectively injected with 10 μL PBS solution containing 1 × 10^5/mL HAECs or 10 pL PBS into the lateral ventricle. The model group was not treated. MAIN OUTCOME MEASURES： TH protein expression in the striatum was evaluated by immunohistochemistry 5 weeks after HAEC transplantation. At 10 weeks, HAEC survival in the lateral ventricle was investigated by immunofluorescent staining; differentiation of HAECs in the lateral and third ventricles was examined by TH immunohistochemistry; concentrations of DA, homovanillic acid, dihydroxyphenyl acetic acid, 5-hydroxyindoleacetic acid, and 5-hydroxytryptamine in the striatum, as well as DA concentration in the cerebrospinal fluid, were measured with high-performance liquid chromatography-electrochemical detection. Circling behavior of PD model rats was consecutively observed for 10 weeks following intraperitoneal injection of amphetamine 1 week after successful model establishment. RESULTS： tn the HAEC group, the number of TH-positive cells significantly increased in the striatum, and circling behavior significantly decreased, compared with the PBS and model groups （P 〈 0.01）. In addition, monoamine concentrations in the striatum, as well as DA concentrations in the cerebrospinal fluid, significantly increased, compared with the PBS group （P 〈 0.05-0.01）. Moreover, a large number of nestin-, vimentin-, and TH-positive cells were observed in the lateral and third ventricles following HAEC injection.CONCLUSION： HAECs survived for 10 weeks with no overgrowth following transplantation into the lateral ventricle of PD model rats. Moreover, the cells differentiated into dopaminergic neurons, which increased DA secretion. HAEC transplantation improved cycling behavior in PD model rats.

Are human dental papilla-derived stem cell and human brain-derived neural stem cell transplantations suitable for treatment of Parkinson’s disease?

Transplantation of neural stem cells has been reported as a possible approach for replacing impaired dopaminergic neurons. In this study, we tested the efficacy of early-stage human dental papilla-derived stem cells and human brain-derived neural stem cells in rat models of 6-hydroxydopamine-induced Parkinson＇s disease. Rats received a unilateral injection of 6-hydroxydopamine into right medial forebrain bundle, followed 3 weeks later by injections of PBS, early-stage human dental papilla-derived stem cells, or human brain-derived neural stem cells into the ipsilateral striatum. All of the rats in the human dental papilla-derived stem cell group died from tumor formation at around 2 weeks following cell transplantation. Postmortem examinations revealed homogeneous malignant tumors in the striatum of the human dental papilla-derived stem cell group. Stepping tests revealed that human brain-derived neural stem cell transplantation did not improve motor dysfunction. In apomorphine-induced rotation tests, neither the human brain-derived neural stem cell group nor the control groups （PBS injection） demonstrated significant changes. Glucose metabolism in the lesioned side of striatum was reduced by human brain-derived neural stem cell transplantation. [18F]-FP-CIT PET scans in the striatum did not demonstrate a significant increase in the human brain-derived neural stem cell group. Tyrosine hydroxylase （dopaminergic neuronal marker） staining and G protein-activated inward rectifier potassium channel 2 （A9 dopaminergic neuronal marker） were positive in the lesioned side of striatum in the human brain-derived neural stem cell group. The use of early-stage human dental papilla-derived stern cells confirmed its tendency to form tumors. Human brain-derived neural stem cells could be partially differentiated into dopaminergic neurons, but they did not secrete dopamine.

Neuroprotective effects of human telomerase reverse transcriptase on beta-amyloid fragment 25-35-treated human embryonic cortical neurons

BACKGROUND： Numerous current studies have suggested that human telomerase reverse transcriptase （hTERT） gene has neuroprotective effects and can inhibit apoptosis induced by various cytotoxic stresses; however, the mechanism of action remains unknown. OBJECTIVE： To evaluate the neuroprotective effects and possible mechanism of action of hTERT gene transfection in human embryonic cortical neurons treated with beta-amyloid fragment 25-35 （AI325-35）. DESIGN, TIME AND SETTING： The randomized, controlled and molecular biological studies were performed at the Department of Anatomy and Brain Research, Zhongshan School of Medicine, Sun Yat-sen University, China, from September 2005 to June 2008. MATERIALS： AdEasy-1 Expression System was gifted by Professor Guoquan Gao from Sun Yat-Sen University, China. Human cortical neurons were derived from 12-20 week old aborted fetuses, obtained from the Guangzhou Maternal and Child Health Hospital, China. Mouse anti-Odk5 and mouse anti-p16 monoclonal antibodies （Lab Vision, USA）, and mouse anti-hTERT monoclonal antibody （Epitomics, USA）, were used in this study. METHODS： （1） Recombinant adenovirus vectors, encoding hTERT （Ad-hTERT） and green fluorescent protein （Ad-GFP）, were constructed using the AdEasy-1 Expression System. Human embryonic cortical neurons in the Ad-hTERT group were transfected with Ad-hTERT for 1-21 days. Likewise, human embryonic cortical neurons in the Ad-GFP group were transfected with Ad-GFP for 1-21 days. Human embryonic cortical neurons in the control group were cultured as normal. （2） Human embryonic cortical neurons in the Ad-hTERT group were treated with 10 pmol/L Aβ25-35 for 24 hours. Normal human embryonic cortical neurons treated with 10 pmol/Lβ25.35 for 24 hours served as a model group. Human embryonic cortical neurons in the Ad-GFP and control groups were not treated with Aβ25-35. MAIN OUTCOME MEASURES： Expression of hTERT in human embryonic cortical neurons was evaluated by immunocytochemical staining and Western blot assay. Telomerase activity was measured using a PCR-based telomeric repeat amplification protocol （TRAP） ELISA kit. Neural activity in human embryonic cortical neurons was examined by MTT assay; apoptosis was measured using TUNEL assay; and Cdk5 and p16 protein expressions were measured by Western blot. RESULTS： Expression of hTERT protein was significantly increased and peaked at day 3 post-transfection in the Ad-hTERT group. No hTERT expression was detected in the Ad-GFP and control groups. Telomerase activity was significantly greater in the Ad-hTERT group compared with the Ad-GFP and control groups （P 〈 0.01）. Compared with the control group, cell activity was significantly decreased （P 〈 0.05）, and cell apoptotic rate, Cdk5 and p16 expression were significantly increased （P 〈 0.01） in the model group. Compared with the model group, cell activity was increased in the Ad-hTERT group, and peaked at day 3 post-transfection （P 〈 0.05）. Neuroprotective effects also peaked at day 3 post-transfection; and the apoptotic rate, Cdk5 and p16 expression significantly decreased （P 〈 0.01）. CONCLUSION： Expression of hTERT in human embryonic cortical neurons can relieve Aβ25-35-induced neuronal apoptosis. The possible mechanism by which hTERT produces these neuroprotective effects may be associated with inhibition of Cdk5 and p16 expression.

Human umbilical cord Wharton's jelly-derived oligodendrocyte precursor-like cells for axon and myelin sheath regeneration

Human umbilical mesenchymal stem cells from Wharton＇s jelly of the umbilical cord were induced to differentiate into oligodendrocyte precursor-like cells in vitro. Oligodendrocyte precursor cells were transplanted into contused rat spinal cords. Immunofluorescence double staining indicated that transplanted cells survived in injured spinal cord, and differentiated into mature and immature oligodendrocyte precursor cells. Biotinylated dextran amine tracing results showed that cell transplantation promoted a higher density of the corticospinal tract in the central and caudal parts of the injured spinal cord. Luxol fast blue and toluidine blue staining showed that the volume of residual myelin was significantly increased at 1 and 2 mm rostral and caudal to the lesion epicenter after cell transplantation. Furthermore, immunofluorescence staining verified that the newly regenerated myelin sheath was derived from the central nervous system. Basso, Beattie and Bresnahan testing showed an evident behavioral recovery. These results suggest that human umbilical mesenchymal stem cell-derived oligodendrocyte precursor cells promote the regeneration of spinal axons and myelin sheaths.