AIM: To isolate nestin-positive progenitor cells from human fetal pancreas and to detect their surface markers and their capability of proliferation and differentiation into pancreatic islet endocrine cells in vitro.M...AIM: To isolate nestin-positive progenitor cells from human fetal pancreas and to detect their surface markers and their capability of proliferation and differentiation into pancreatic islet endocrine cells in vitro.METHODS: Islet-like cell clusters (ICCs) were isolated from human fetal pancreas by using collagenase digestion. The free-floating ICCs were handpicked and cultured in a new dish. After the ICCs developed into monolayer epithelium-like cells, they were passaged and induced for differentiation. Reverse transcription polymerase chain reaction (RT-PCR), immunofluorescence stain, fluorescenceactivated cell sorting (FACS) and radioimmunoassay (RIA)were used to detect the expression of cell markers. RESULTS: (1) The monolayer epithelium-like cells had highly proliferative potential and could be passaged more than 16 timesin vitro; (2) RT-PCR analysis and immunofluorescence stain showed that these cells expressed both nestin and ABCG2, two of stem cellmarkers; (3) FACS analysis revealed that CD44, CD90and CD147 were positive, whereas CD34, CD38, CD45, CD71, CD117, CD133 and HLA-DR were negative on the nestin-positive cells; (4) RT-PCR analysis showed that the mRNA expression of insulin, glucagon and pancreaticduodenal homeobox gene-1 was detected, whereas the expression of nestin and neurogenin 3 disappeared in these cells treated with serum-free media supplemented with the cocktail of growth factors. Furthermore, the intracellular insulin content was detected by RIA after the induction culture.CONCLUSION: Nestin-positive cells isolated from human fetal pancreas possess the characteristics of pancreatic progenitor cells since they have highly proliferative potential and the capability of differentiation into insulinproducing cells in vitro. Interestingly, the nestin-positive pancreatic progenitor cells share many phenotypic markers with mesenchymal stem cells derived from bone marrow.展开更多
AIM: To investigate whether Thyl recognizes oval cells in the fetal liver and to characterize the cultured Thy1 selected cells from E14 rat livers. METHODS: Thyl populations were analyzed by fluorescence activated c...AIM: To investigate whether Thyl recognizes oval cells in the fetal liver and to characterize the cultured Thy1 selected cells from E14 rat livers. METHODS: Thyl populations were analyzed by fluorescence activated cell sorter analysis. Thyl positive cells were isolated using magnetic beads. Hepatic markers were detected by Western blotting, immunocytochemistry and RT-PCR. RESULTS: The percentage of Thyl-positive cells decreased during early development of fetal rat liver (E13-E16). E14 fetal livers contained 7.8% Thy1 positive cells, of which 61% were positive for α-fetoprotein (AFP) and 25% expressed albumin. The Thy1+ population expressed oval cell markers c-Kit and CXCR4, liver enriched-transcription factors HNF1α and HNF6, hepatocytic markers albumin, AFP and cytokeratin 18, and biliary marker cytokeratin 19. Thy1- selected cells formed only mesenchymal colonies when plated on collagen and in serum-containing media. Thyl selected cells were able to form hepatic colonies positive for HNF1α, HNF6, albumin, AFP, cytokeratin 18, cytokeratin 19 and glycogen, when grown on STO feeder layers in serum free-media. CONCLUSION: Oval cells positive for Thyl are present in early liver embryonic stages.展开更多
Choledochal cysts are congenital anomalies of the biliary ducts, characterized by cystic dilatation of the ducts.Prenatal diagnosis of this anomaly using ultrasonography (US) has been well documented. Magnetic resonan...Choledochal cysts are congenital anomalies of the biliary ducts, characterized by cystic dilatation of the ducts.Prenatal diagnosis of this anomaly using ultrasonography (US) has been well documented. Magnetic resonance imaging (MRI) has recently become an important complement to US in prenatal diagnosis of fetal anomalies. We herein report a patient in whom at 24 wk' gestation US suggested a right upper quadrant abdominal cyst and in whom at 26 wk' gestation MRI more clearly delineated the cyst and its surrounding structures and suggested a choledochal cyst, which was confirmed at postnatal surgery and histopathology.展开更多
Primary ovarian insufficiency(POI) occurs in about 1% of female population under the age of 40,leading to reproductive problems,an earlier encounter with menopausal symptoms,and complicated diseases.There are three pr...Primary ovarian insufficiency(POI) occurs in about 1% of female population under the age of 40,leading to reproductive problems,an earlier encounter with menopausal symptoms,and complicated diseases.There are three presumable mechanisms involved in the development of POI,namely apoptosis acceleration,follicular maturation blocking and premature follicle activation,through the following studied causes:(i) chromosomal abnormalities or gene mutations:mostly involve X chromosome,such as FMR1 premutation;more and more potentially causal genes have been screened recently;(ii) metabolic disorders such as classic galactosaemia and 17-OH deficiency;(iii) autoimmune mediated ovarian damage:observed alone or with some certain autoimmune disorders and syndromes;but the specificity and sensitivity of antibodies towards ovary are still questionable;(iv) iatrogenic:radiotherapy or chemotherapy used in cancer treatment,as well as pelvic surgery with potential threat to ovaries' blood supply can directly damage ovarian function;(v) virus infection such as HIV and mumps;(vi) toxins and other environmental/lifestyle factors:cigarette smoking,toxins(e.g.,4-vinylcyclohexene diepoxide),and other environmental factors are associated with the development of POI.The etiology of a majority of POI cases is not identified,and is believed to be multifactorial.Strategies to POI include hormone replacement and infertility treatment.Assisted conception with donated oocytes has been proven to achieve pregnancy in POI women.Embryo cryopreservation,ovarian tissue cryopreservation and oocyte cryopreservation have been used to preserve ovarian reserve in women undergoing cancer treatments.展开更多
Objective: To investigate the expression and pattern of vascular endothelial growth factor (VEGF) and its fetal liver kinase-1 (Flk-1) receptor in spinal cord and dorsal root ganglia after neurotomy of sciatic nerve i...Objective: To investigate the expression and pattern of vascular endothelial growth factor (VEGF) and its fetal liver kinase-1 (Flk-1) receptor in spinal cord and dorsal root ganglia after neurotomy of sciatic nerve in rats. Methods: Forty-five adult male Wistar rats were divided randomly into a control group (n=5) and an experimental group (n=40). The bilateral sciatic nerves of the rats in the experimental group underwent neurotomy and the L 4-L 6 spinal cord and the corresponding dorsal root ganglia were harvested respectively at 8 hours, and 1, 3, 5, 7, 10, 14 and 21 days (8 subgroups with 5 rats each) after operation. The rats in the control group only underwent an exposure of sciatic nerve without neurotomy. Immunohistochemistry and image analysis were used to study the expression of VEGF and its Flk-1 receptor. Results: Both VEGF and Flk-1 receptor expressed in the normal rat spinal cord and dorsal root ganglia. In response to neurotomy, their expression reached a higher level and persisted for a short time then declined to the normal level rapidly. Besides, positive staining of Flk-1 was observed in both glial cells and nerve fibers, which located in the white matter of the spinal cord.Conclusions: VEGF can promote the regeneration of peripheral nerves from the angle of central neurons, which establishes the experimental and theoretical foundation for VEGF treating peripheral nerve injuries.展开更多
Kindlin-2 functions in the maintenance of homeostasis and in human diseases.This study investigated the interrelationship between Kindlin-2 expression in tissues and the corresponding germ layers from which these tiss...Kindlin-2 functions in the maintenance of homeostasis and in human diseases.This study investigated the interrelationship between Kindlin-2 expression in tissues and the corresponding germ layers from which these tissues originated.Kindlin-2 expression was examined in normal adult human organs and human cancer tissues by immunohistochemical analyses.Analysis of Kindlin-2 mRNA levels in adult human organs in the Oncomine dataset revealed Kindlin-2 is highly expressed in mesoderm-derived organs.However,Kindlin-2 was negative or weakly expressed in endoderm/ectoderm-derived organs.Interestingly,the abnormal expression of Kindlin-2 was observed in a variety of human cancers.In agreement with its expression profile in humans,Kindlin-2 was also highly expressed in mesoderm-derived organs in mouse embryos with the exception of strong Kindlin-2 expression in ectoderm-derived spinal cord and ganglia,tissues that are highly mobile during embryonic development.Importantly,we demonstrated the expression level of Kindlin-2 in adult organs correlated with their embryonic dermal origins and deregulation of Kindlin-2 in tissues is associated with tumor progression.This finding will help us understand the dual role of Kindlin-2 in the regulation of tumor progression and embryonic development.展开更多
基金Supported by the National Natural Science Foundation of China,No. 30170443 Major State Basic Research Development Program of China, No. 2001CB510105 and "211" Project Foundation of Peking University
文摘AIM: To isolate nestin-positive progenitor cells from human fetal pancreas and to detect their surface markers and their capability of proliferation and differentiation into pancreatic islet endocrine cells in vitro.METHODS: Islet-like cell clusters (ICCs) were isolated from human fetal pancreas by using collagenase digestion. The free-floating ICCs were handpicked and cultured in a new dish. After the ICCs developed into monolayer epithelium-like cells, they were passaged and induced for differentiation. Reverse transcription polymerase chain reaction (RT-PCR), immunofluorescence stain, fluorescenceactivated cell sorting (FACS) and radioimmunoassay (RIA)were used to detect the expression of cell markers. RESULTS: (1) The monolayer epithelium-like cells had highly proliferative potential and could be passaged more than 16 timesin vitro; (2) RT-PCR analysis and immunofluorescence stain showed that these cells expressed both nestin and ABCG2, two of stem cellmarkers; (3) FACS analysis revealed that CD44, CD90and CD147 were positive, whereas CD34, CD38, CD45, CD71, CD117, CD133 and HLA-DR were negative on the nestin-positive cells; (4) RT-PCR analysis showed that the mRNA expression of insulin, glucagon and pancreaticduodenal homeobox gene-1 was detected, whereas the expression of nestin and neurogenin 3 disappeared in these cells treated with serum-free media supplemented with the cocktail of growth factors. Furthermore, the intracellular insulin content was detected by RIA after the induction culture.CONCLUSION: Nestin-positive cells isolated from human fetal pancreas possess the characteristics of pancreatic progenitor cells since they have highly proliferative potential and the capability of differentiation into insulinproducing cells in vitro. Interestingly, the nestin-positive pancreatic progenitor cells share many phenotypic markers with mesenchymal stem cells derived from bone marrow.
基金Supported by the Genesis Consortium for Cell Therapy, Israel Ministry of Science
文摘AIM: To investigate whether Thyl recognizes oval cells in the fetal liver and to characterize the cultured Thy1 selected cells from E14 rat livers. METHODS: Thyl populations were analyzed by fluorescence activated cell sorter analysis. Thyl positive cells were isolated using magnetic beads. Hepatic markers were detected by Western blotting, immunocytochemistry and RT-PCR. RESULTS: The percentage of Thyl-positive cells decreased during early development of fetal rat liver (E13-E16). E14 fetal livers contained 7.8% Thy1 positive cells, of which 61% were positive for α-fetoprotein (AFP) and 25% expressed albumin. The Thy1+ population expressed oval cell markers c-Kit and CXCR4, liver enriched-transcription factors HNF1α and HNF6, hepatocytic markers albumin, AFP and cytokeratin 18, and biliary marker cytokeratin 19. Thy1- selected cells formed only mesenchymal colonies when plated on collagen and in serum-containing media. Thyl selected cells were able to form hepatic colonies positive for HNF1α, HNF6, albumin, AFP, cytokeratin 18, cytokeratin 19 and glycogen, when grown on STO feeder layers in serum free-media. CONCLUSION: Oval cells positive for Thyl are present in early liver embryonic stages.
文摘Choledochal cysts are congenital anomalies of the biliary ducts, characterized by cystic dilatation of the ducts.Prenatal diagnosis of this anomaly using ultrasonography (US) has been well documented. Magnetic resonance imaging (MRI) has recently become an important complement to US in prenatal diagnosis of fetal anomalies. We herein report a patient in whom at 24 wk' gestation US suggested a right upper quadrant abdominal cyst and in whom at 26 wk' gestation MRI more clearly delineated the cyst and its surrounding structures and suggested a choledochal cyst, which was confirmed at postnatal surgery and histopathology.
文摘Primary ovarian insufficiency(POI) occurs in about 1% of female population under the age of 40,leading to reproductive problems,an earlier encounter with menopausal symptoms,and complicated diseases.There are three presumable mechanisms involved in the development of POI,namely apoptosis acceleration,follicular maturation blocking and premature follicle activation,through the following studied causes:(i) chromosomal abnormalities or gene mutations:mostly involve X chromosome,such as FMR1 premutation;more and more potentially causal genes have been screened recently;(ii) metabolic disorders such as classic galactosaemia and 17-OH deficiency;(iii) autoimmune mediated ovarian damage:observed alone or with some certain autoimmune disorders and syndromes;but the specificity and sensitivity of antibodies towards ovary are still questionable;(iv) iatrogenic:radiotherapy or chemotherapy used in cancer treatment,as well as pelvic surgery with potential threat to ovaries' blood supply can directly damage ovarian function;(v) virus infection such as HIV and mumps;(vi) toxins and other environmental/lifestyle factors:cigarette smoking,toxins(e.g.,4-vinylcyclohexene diepoxide),and other environmental factors are associated with the development of POI.The etiology of a majority of POI cases is not identified,and is believed to be multifactorial.Strategies to POI include hormone replacement and infertility treatment.Assisted conception with donated oocytes has been proven to achieve pregnancy in POI women.Embryo cryopreservation,ovarian tissue cryopreservation and oocyte cryopreservation have been used to preserve ovarian reserve in women undergoing cancer treatments.
文摘Objective: To investigate the expression and pattern of vascular endothelial growth factor (VEGF) and its fetal liver kinase-1 (Flk-1) receptor in spinal cord and dorsal root ganglia after neurotomy of sciatic nerve in rats. Methods: Forty-five adult male Wistar rats were divided randomly into a control group (n=5) and an experimental group (n=40). The bilateral sciatic nerves of the rats in the experimental group underwent neurotomy and the L 4-L 6 spinal cord and the corresponding dorsal root ganglia were harvested respectively at 8 hours, and 1, 3, 5, 7, 10, 14 and 21 days (8 subgroups with 5 rats each) after operation. The rats in the control group only underwent an exposure of sciatic nerve without neurotomy. Immunohistochemistry and image analysis were used to study the expression of VEGF and its Flk-1 receptor. Results: Both VEGF and Flk-1 receptor expressed in the normal rat spinal cord and dorsal root ganglia. In response to neurotomy, their expression reached a higher level and persisted for a short time then declined to the normal level rapidly. Besides, positive staining of Flk-1 was observed in both glial cells and nerve fibers, which located in the white matter of the spinal cord.Conclusions: VEGF can promote the regeneration of peripheral nerves from the angle of central neurons, which establishes the experimental and theoretical foundation for VEGF treating peripheral nerve injuries.
基金supported by the National Natural Science Foundation of China (81301802,81230051,30830048,81321003,31170711)Ministry of Science and Technology of China (2013CB910501,2010CB912203,2010CB529402)+3 种基金Program of Introducing Talents of Discipline to Universities of Ministry of EducationBeijing Natural Science Foundation (7120002)Peking University (BMU20120314,BMU20130364)a Leading Academic Discipline Project of Beijing Education Bureau
文摘Kindlin-2 functions in the maintenance of homeostasis and in human diseases.This study investigated the interrelationship between Kindlin-2 expression in tissues and the corresponding germ layers from which these tissues originated.Kindlin-2 expression was examined in normal adult human organs and human cancer tissues by immunohistochemical analyses.Analysis of Kindlin-2 mRNA levels in adult human organs in the Oncomine dataset revealed Kindlin-2 is highly expressed in mesoderm-derived organs.However,Kindlin-2 was negative or weakly expressed in endoderm/ectoderm-derived organs.Interestingly,the abnormal expression of Kindlin-2 was observed in a variety of human cancers.In agreement with its expression profile in humans,Kindlin-2 was also highly expressed in mesoderm-derived organs in mouse embryos with the exception of strong Kindlin-2 expression in ectoderm-derived spinal cord and ganglia,tissues that are highly mobile during embryonic development.Importantly,we demonstrated the expression level of Kindlin-2 in adult organs correlated with their embryonic dermal origins and deregulation of Kindlin-2 in tissues is associated with tumor progression.This finding will help us understand the dual role of Kindlin-2 in the regulation of tumor progression and embryonic development.