Objective Intravenous administration of basic fibroblast growth factor (bFGF) is effective to reduce the volume of cerebral infract due to ischemia. This study was designed to investigate the molecular mechanism, es...Objective Intravenous administration of basic fibroblast growth factor (bFGF) is effective to reduce the volume of cerebral infract due to ischemia. This study was designed to investigate the molecular mechanism, especially the signal transduction pathways, involved in this protective role of bFGF. Methods Anoxia-reoxygenation treated atrocytes were used to study the role of mitogen-activated protein kinase/extracellular signal-regulated kinase kinase (MAPK/ERK kinase, MEK)-ERK signaling pathway after exogenous bFGF administration by Western blot. Electrophoretic mobile shift assay was used to detect the binding activity of early growth response factor-1 (Egr-1), an important transcription factor for endogenous bFGF. Results bFGF could protect some signal transduction proteins from the oxygen-derived free radicals induced degradation. ERK1/2 was activated and involved in Egr-1 binding activity enhancement induced by exogenous bFGF. Conclusion MEK-ERK MAPK cascade may be an important signal transduction pathway contributed to bFGF induced enhancement of Egr-1 binding activity in anoxia-reoxygenation injured astrocytes.展开更多
[ Objective] The study is to generate pharmaceutical protein via plant transgenic technique. [Methed] Using the cotyledons with petiole as transformation receptor, the fusion gene of rapeseed oil-body gene and bFGF wa...[ Objective] The study is to generate pharmaceutical protein via plant transgenic technique. [Methed] Using the cotyledons with petiole as transformation receptor, the fusion gene of rapeseed oil-body gene and bFGF was introduced into the rapeseed ( Brassica campestris L. ) by Agrobacterium tumefaciens-mediated transformation; meanwhile regeneration conditions of rapeseed were also optimized, and the regenerated resistant plantlets were detected by PCR and Southern blot. [ Result] This fusion gene had been integrated into rapeseed genome successfully, and the optimized conditions of transformation and regeneration were as follows: explants pre-culture for 2 d, co-culture for 3 d, bacteria solution OD600 for 0.3 and infection time for 5 min. [ Conclusion] The results laid a solid foundation for extraction, isolation and purification of protein in transgenic plant seeds.展开更多
AIM: To examine fibroblast activation protein (FAP) expression in pancreatic ductal adenocarcinoma (PDAC) and to analyze its relationship with the clinicopathology of PDAC. METHODS: FAP expression was examined in 134 ...AIM: To examine fibroblast activation protein (FAP) expression in pancreatic ductal adenocarcinoma (PDAC) and to analyze its relationship with the clinicopathology of PDAC. METHODS: FAP expression was examined in 134 PDAC specimens by immunohistochemistry, and in four pancreatic cancer cell lines (SW1990, Miapaca-2, AsPC-1 and BxPC-3) by Western blotting assay. We also analyzed the association between FAP expression in PDAC cells and the clinicopathology of PDAC patients. RESULTS: The results showed that the FAP was expressed in both stromal fibroblast cells (98/134, 73.1%) and carcinoma cells (102/134, 76.1%). All 4 pancreatic cancer cell lines expressed FAP protein at different levels. Protein bands corresponding to the proteolytically active 170-kDa seprase dimer and its88-kDa seprase subunit were identif ied. Higher FAP expression in carcinoma cells was associated with tumor size (P < 0.001), fi brotic focus (P = 0.003), perineural invasion (P = 0.009) and worse clinical outcome (P = 0.0085). CONCLUSION: FAP is highly expressed in carcinoma cells and f ibroblasts in PDAC tissues, and its expression is associated with desmoplasia and worse prognosis.展开更多
AIM:To investigate the inhibitory role of toxicarioside A on the gastric cancer cell line human gastric cancer cell line(SGC-7901) and determine the underlying molecular mechanism.METHODS:After SGC-7901 cells were tre...AIM:To investigate the inhibitory role of toxicarioside A on the gastric cancer cell line human gastric cancer cell line(SGC-7901) and determine the underlying molecular mechanism.METHODS:After SGC-7901 cells were treated with toxicarioside A at various concentrations(0.5,1.5,4.5,9.0 μg/mL) for 24 h or 48 h,cell viability was determined by 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl2H-tetrazolium bromide assay,and the motility and invasion of tumor cells were assessed by the Transwell chamber assay.Immunofluorescence staining,reverse transcription polymerase chain reaction and Western blotting were performed to detect the expression of basic fibroblast growth factor(bFGF) and fibroblast growth factor receptor-1(FGFR1),and nuclear factorkappa B(NF-κB) activation was examined by electrophoretic mobility shift assay.RESULTS:The results showed that toxicarioside A was capable of reducing cell viability,inhibiting cell growth,and suppressing cell migration and invasion activities in a time-and dose-dependent manner in SGC-7901 cells.Further analysis revealed that not only the expression of bFGF and its high-affinity receptor FGFR1 but also the NF-κB-DNA binding activity were effectively blocked by toxicarioside A in a dose-dependent manner compared with the control group(P < 0.05 or P < 0.01).Interestingly,application of the NF-κB specific inhibitor,pyrrolidinedithiocarbamate(PDTC),to SGC-7901 cells significantly potentized the toxicarioside A-induced down-regulation of bFGF compared with the control group(P < 0.05).CONCLUSION:These findings suggest that toxicarioside A has an anti-gastric cancer activity and this effect may be achieved partly through down-regulation of NF-κB and bFGF/FGFR1 signaling.展开更多
A paracrine regulation was recently proposed in human embryonic stem cells (hESCs) grown in mouse embryonic fibroblast (MEF)-conditioned media (MEF-CM), where hESCs spontaneously differentiate into autologous fi...A paracrine regulation was recently proposed in human embryonic stem cells (hESCs) grown in mouse embryonic fibroblast (MEF)-conditioned media (MEF-CM), where hESCs spontaneously differentiate into autologous fibroblastlike cells to maintain culture homeostasis by producing TGF-β and insulin-like growth factor-lI (IGF-Ⅱ) in response to basic fibroblast growth factor (bFGF). Although the importance of TGF-β family members in the maintenance of pluripotency of hESCs is widely established, very little is known about the role of IGF-Ⅱ. In order to ease hESC cul- ture conditions and to reduce xenogenic components, we sought (i) to determine whether hESCs can be maintained stable and pluripotent using CM from human foreskin fibroblasts (HFFs) and human mesenchymal stem cells (hM- SCs) rather than MEF-CM, and (ii) to analyze whether the cooperation of bFGF with TGF-β and IGF-Ⅱ to maintain hESCs in MEF-CM may be extrapolated to hESCs maintained in allogeneic mesenchymal stem cell (MSC)-CM and HFF-CM. We found that MSCs and HFFs express all FGF receptors (FGFR1-4) and specifically produce TGF-β in response to bFGF. However, HFFs but not MSCs secrete IGF-Ⅱ. Despite the absence of IGF-Ⅱ in MSC-CM, hESC pluripotency and culture homeostasis were successfully maintained in MSC-CM for over 37 passages. Human ESCs derived on MSCs and hESCs maintained in MSC-CM retained hESC morphology, euploidy, expression of surface markers and transcription factors linked to pluripotency and displayed in vitro and in vivo multilineage developmental potential, suggesting that IGF-Ⅱ may be dispensable for hESC pluripotency. In fact, IGF-Ⅱ blocking had no effect on the homeostasis of hESC cultures maintained either on HFF-CM or on MSC-CM. These data indicate that hESCs are successfully maintained feeder-free with IGF-Ⅱ-lacking MSC-CM, and that the previously proposed paracrine mechanism by which bFGF cooperates with TGF-β and IGF-Ⅱ in the maintenance of hESCs in MEF-CM may not be fully extrapolated to hESCs maintained in CM from human MSCs.展开更多
A cell line, SHK, was derived from the kidney of spotted halibut Verasper variegates. The cell line was subcultured more than 40 passages in minimum essential medium (MEM) supplemented with fetal bovine serum (FBS...A cell line, SHK, was derived from the kidney of spotted halibut Verasper variegates. The cell line was subcultured more than 40 passages in minimum essential medium (MEM) supplemented with fetal bovine serum (FBS) and 10 ng ml4 basic fibroblast growth factor (bFGF). Cell morphology from primary culture and subculture was observed continuously by microscopy. The SHK cell line consisted predominantly of fibroblast-like cells. The cell line was able to grow between 20℃ and 30℃ with the optimum growth at 24℃ and with a reduced growth between 12℃ and 20℃. The growth rate of the cells increased as the proportion of FBS increased from 10% to 20% at 28℃ with optimum growth at the concentration of 20%. The doubling time of the cells was determined to be 44.8 h. Chromosome analysis revealed that 52% of the SHK cells maintained a normal diploid chromosome number (2n=46). The cells were successfully transfected with green fluorescent protein (GFP) reporter plasmids and the expression of GFP gene in the cells indicated the possible utility of the cells in gene expression studies. The cells were infected by lymphosystis disease virus (LCDV) and found to be susceptible to the virus in cytopathic effect (CPE) observation. The infection was confirmed by PCR and electron microscopy experiments, which proved the existence of the viral particles in the cytoplasm of the virus-infected cells.展开更多
AIM:To study the inhibition of tumor angiogenesis by 5,2,4'-trihydroxy-6,7,5'-trimethoxyflavone(TTF1) isolated from an extract of herbal medicine Sorbaria sorbifolia.METHODS:Angiogenic activity was assayed usi...AIM:To study the inhibition of tumor angiogenesis by 5,2,4'-trihydroxy-6,7,5'-trimethoxyflavone(TTF1) isolated from an extract of herbal medicine Sorbaria sorbifolia.METHODS:Angiogenic activity was assayed using the chick embryo chorioallantoic membrane(CAM) method.Microvessel density(MVD) was determined by staining tissue sections immunohistochemically for CD34 using the Weidner capillary counting method.The mRNA and protein levels of vascular endothelial growth factor(VEGF),vascular endothelialgrowth factor receptor 2(VEGFR2,Flk-1/KDR),basic fibroblast growth factor(bFGF),cyclo-oxygenase(COX)-2 and hypoxia-inducible factor(HIF)-1α were detected by quantitative real-time polymerase chain reaction and Western blotting analysis.RESULTS:The TTF1 inhibition rates for CAM were 30.8%,38.2% and 47.5% with treatment concentrations of 25,50 and 100 μg/embryo × 5 d,respectively.The inhibitory rates for tumor size were 43.8%,49.4% and 59.6% at TTF1 treatment concentrations of 5,10,and 20 μmol/kg,respectively.The average MVD was 14.2,11.2 and 8.5 at treatment concentrations of 5 μmol/kg,10 μmol/kg and 20 μmol/kg TTF1,respectively.The mRNA and protein levels of VEGF,KDR,bFGF,COX-2 and HIF-1α in mice treated with TTF1 were significantly decreased.CONCLUSION:TTF1 can inhibit tumor angiogenesis,and the mechanism may be associated with the down-regulation of VEGF,KDR,bFGF,HIF-1α and COX-2.展开更多
The aim of this study was to develop a synthetic medium for the in vitro culture of bovine embryos, using various growth factors and cytokines (GF-CYK): insulin-like growth factorl (IGF-Ⅰ), insulin-like growth f...The aim of this study was to develop a synthetic medium for the in vitro culture of bovine embryos, using various growth factors and cytokines (GF-CYK): insulin-like growth factorl (IGF-Ⅰ), insulin-like growth factorⅡ (IGF-Ⅱ), basic fibroblast growth factor (bFGF), leukemia inhibitory factor (LIF), granulocyte-macrophage colony stimulating factor (GM-CSF) and transforming growth factor beta Ⅰ (TGF-β1) + hyaluronan (HA) + recombinant albumin (RA). The embryos were cultured in synthetic oviduct fluid (SOF) supplemented with: treatment 1 (T1): bovine serum albumin (BSA) + insulin, transferrin and selenium (ITS) (control); or treatment 2 (T2): GF-CYK + HA + RA. The blastocyst rates were not significantly different between TI and T2, at seven days post fertilization (dpf) (28.9% ± 2.4% and 31.8% ±2.2%), and at 8 dpf (36.5% ±2.4% and 39.1% ±1.9%), respectively (P 〉 0.05). The total cell number (TCN) was significantly higher with T2 than that with T1 at 7 dpf(164.9 ±5.3 and 149.7 ±4.0) and 8 dpf (182.7 ±6.4 and 165.0 ±5.5) (P 〈 0.05). The blastocyst diameter obtained with T2 was significantly greater (P 〈 0.05) than with T1 at 7 dpf (173.3 μm ±4.9 μm and 157.2μm ±4.1 μm, respectively), however, no significant differences were observed at 8 dpf (190.3 μm 5.2 μm and 179.7 μm ± 5.3 μm, respectively). In conclusion, the synthetic medium (T2) shows a comparable development rate to the control medium and improves the blastocyst diameter and the TCN.展开更多
Objective: to observe expression of vascular endothelial growth factor-C (VEGF-C) and alkaline fibroblast growth factor (b-FGF) in tissues of lung cancer, and its relationship with cancer metastasis.Methods: to ...Objective: to observe expression of vascular endothelial growth factor-C (VEGF-C) and alkaline fibroblast growth factor (b-FGF) in tissues of lung cancer, and its relationship with cancer metastasis.Methods: to adopt immunohistochemical methods, analysis of 60 cases of lung tissue expression of VEGF-C and b-FGF in the situation.Result: positive rates of VEGF-C and b-FGF in lung cancer are respectively 56.67% and 63.33%; expression of VEGF-C and b-FGF in lung cancer is not related to pathological grades, pathologic stages or ages of patients (P 〉 0.05),but closely related to TNM stages and existence of lymph node metastasis (P 〈 0.01). IMVD in center of lung cancer tissues is obviously higher than surrounding area, with significant differences (P 〈 0.01). Conclusion: expression of VEGF-C and b-FGF is related to lung cancer progress.展开更多
OBJECTIVE: To evaluate the safety and efficacy of topical application of recombinant bovine basic fibroblast growth factor (rbFGF) on the healing of chronic cutaneous wounds. METHODS: Twenty-eight patients with thirty...OBJECTIVE: To evaluate the safety and efficacy of topical application of recombinant bovine basic fibroblast growth factor (rbFGF) on the healing of chronic cutaneous wounds. METHODS: Twenty-eight patients with thirty-three chronic cutaneous wounds resulting from trauma, diabetes mellitus, pressure sore and radiation injuries were enrolled in this prospective, open-label crossover trial. Prior to treatment with rbFGF, all wounds failed to heal with conventional therapies within 4 weeks. All wounds were locally treated with rbFGF at a dose of 150 AU/cm(2). Healing time and the quality of wounds were used to evaluate the efficacy of the treatment. RESULTS: Healing of all chronic wounds was expedited. During the study, eighteen wounds completely healed within 2 weeks, four healed within 3 weeks, and another eight completely healed within 4 weeks. Only three wounds failed to heal within 4 weeks, but healed at 30, 40 and 42 days after treatment with rbFGF. Thus, compared with conventional therapies, the effective rate of rbFGF treatment within 4 weeks was 90.9%. Histological assessment showed more abundant capillary sprouts or tubes and that fibroblasts were differentiated in wounds treated with rbFGF. No adverse side effects related to basic fibroblast growth factor were observed. CONCLUSIONS: Our results indicate that rbFGF could be used to accelerate healing in chronic wounds. It is our belief that this may be a more effective method of chronic wound management.展开更多
OBJECTIVE: To detect the expression of basic fibroblast growth factor (bFGF) in human ocular tissues, and to assess the effect of bFGF on the proliferation of human cataract lens epithelial cells (LECs) and its correl...OBJECTIVE: To detect the expression of basic fibroblast growth factor (bFGF) in human ocular tissues, and to assess the effect of bFGF on the proliferation of human cataract lens epithelial cells (LECs) and its correlation with age. METHODS: Enucleated eyes were subjected to immunostaining for bFGF protein. Human cataract LECs were cultured in vitro, and treated with bFGF for 48 hr. Proliferation was estimated by the positive area ratio of proliferating cell nuclear antigen (PCNA) in immunohistochemistry. RESULTS: bFGF protein was found in various human ocular tissues. bFGF stimulated human cataract LEC proliferation, and there was an age-related decrease in responsiveness of human cataract LECs to bFGF (P展开更多
Objective The present study is to observe in vitro the proliferation ability of the muscle cells from permanent myopathy (PM) patients of nomokalaemic periodic paralysis (normKPP), which is caused by mutations of ...Objective The present study is to observe in vitro the proliferation ability of the muscle cells from permanent myopathy (PM) patients of nomokalaemic periodic paralysis (normKPP), which is caused by mutations of Metl592Val in the skeletal muscle voltage gated sodium channel (SCN4A) gene on chromosome 17q23.1. We also evaluate the possible effect of the foreign basic fibroblast growth factor (bFGF) in preventing and curing PM. Methods The gastrocnemius muscle cells were taken from two male patients with PM of the same Chinese family with Metl592Val mutation of SCN4A, determined by gene screening. Four male patients suffering from the skeletal injury without PM were taken as control. All preparations were protogenerationally cultured in vitro. Proliferation of the cultured preparations was measured by MTT. Activities of the lactic dehydrogenase (LDH), creatine kinase (CK), and protein content in these cells were also detected. The effects of bFGF with different doses (10 ng/mL, 20 ng/mL, 40 ng/mL, 80 ng/mL, 120 ng/mL and 160 ng/mL) on the above mentioned parameters were also evaluated. Results Cells from both PM and control subjects were successfully cultured in vitro. The cultivation of the muscle cells from PM patients in vitro was not yet seen. Results indicated the obvious stimulation of bFGF on cell proliferation, activities of LDH and CK, protein synthesis, in a dose dependent manner. The optimal dose of bFGF was 120 ng/mL (P〈0.05), beyond which greater dose caused a less effect. The effect of bFGF on 160 ng/mL was stronger than that on 80 ng/mL, but there was no significant difference (P〉0.05). Conclusion Myoblastic cells from patients with PM had a weaker ability of developing into the myotubules, thus they were unable to perform effective regeneration, which resulted in a progressive necrosis. The exogenous bFGF could promote the division and proliferation of the muscle cells in vitro. These results shield a light on bFGF's potential role in preventing and treating PM.展开更多
Nerve conduit is one of strategies for spine cord injury(SCI)treatment.Recently,studies showed that biomaterials could guide the neurite growth and promote axon regeneration at the injury site.However,the scaffold by ...Nerve conduit is one of strategies for spine cord injury(SCI)treatment.Recently,studies showed that biomaterials could guide the neurite growth and promote axon regeneration at the injury site.However,the scaffold by itself was difficult to meet the need of SCI functional recovery.The basic fibroblast growth factor(bFGF)administration significantly promotes functional recovery after organ injuries.Here,using a rat model of T9 hemisected SCI,we aimed at assessing the repair capacity of implantation of collagen scaffold(CS)modified by collagen binding bFGF(CBD-bFGF).The results showed that CS combined with CBD-bFGF treatment improved survival rates after the lateral hemisection SCI.The CS/CBD-bFGF group showed more significant improvements in motor than the simply CS-implanted and untreated control group,when evaluated by the 21-point Basso-Beattie-Bresnahan(BBB)score and footprint analysis.Both hematoxylin and eosin(H&E)and immunohistochemical staining of neurofilament(NF)and glial fibrillary acidic protein(GFAP)demonstrated that fibers were guided to grow through the implants.These findings indicated that administration of CS modified with CBD-bFGF could promote spinal cord regeneration and functional recovery.展开更多
OBJECTIVE: To investigate the effects and mecha- nisms of Erbanxiao solution in inhibiting tumor an- giogenesis. METHODS: We observed the effects and mecha- nisms of Chinese medicines on inhibiting tumor an- giogene...OBJECTIVE: To investigate the effects and mecha- nisms of Erbanxiao solution in inhibiting tumor an- giogenesis. METHODS: We observed the effects and mecha- nisms of Chinese medicines on inhibiting tumor an- giogenesis and studied the theories and results of treatment. Sixty patients with lung cancer were ran- domized into two groups (n=30). Patients in the control group were given compound Kushen injec- tion, and patients in the treatment group were giv- en Erbanxiao solution. The effect of Erbanxiao solu- tion on vascular endothelium growth factor (VEGF), basic fibroblast growth factor (bFGF), and tumor ne- crosis factor-α (TNF-α) was observed. RESULTS: The effective rate of the treatment group was 60% while the control group was 36%. There was a significant difference between the twogroups (P〈0.05). VEGF, bFGF, and TNF-a levels of the two groups were significantly different before and after treatment (P〈0.01). These Traditional Chi- nese Medicines significantly inhibited tumor angio- genesis, possibly by changing levels of VEGF, bFGF, and TNF-α. CONCLUSION: It is necessary to further explore the potential of Traditional Chinese Medicine in the treatment of angiogenesis in tumor patients.展开更多
Peripheral nerve functional recovery after nerve injury generally requires multiple growth factors by synergistic effect.However,the optical combination of multiple synergistic growth factors for axonal regeneration h...Peripheral nerve functional recovery after nerve injury generally requires multiple growth factors by synergistic effect.However,the optical combination of multiple synergistic growth factors for axonal regeneration has been scarcely considered up to now.Meanwhile,the use of growth factors in promoting nerve regeneration was limited by its short biological half-life in vivo,its vulnerability to structure disruption or hydrolyzation,leading to loss of bioactivity.Herein,a novel polymeric nanoparticle delivery system composed of heparin andε-poly-L-lysine(PL)was prepared for control release of nerve growth factor(NGF)and basic fibroblast growth factor(bFGF).The nanoparticles were synthesized by polyelectrolyte complexation in aqueous solution at room temperature,followed by cross-linking with biological genipin.The obtained nanoparticles had a spherical shape,with a mean diameter of about 246 nm,and high growth factors encapsulation efficiency as well as good stability.NGF and bFGF were encapsulated in the nanoparticles and showed a continuous and slow release behavior in vitro.The bioactivities of the released growth factors were evaluated,and exhibited the synergistic effect.The controlled release of the dual synergistic growth factors would improve the treatment of peripheral nerve injury to mimic the natural cellular microenvironments.展开更多
Induced pluripotent stem (iPS) cell technology demonstrates that somatic cells can be reprogrammed to a pluripotent state by over-expressing four reprogramming factors.This technology has created an interest in derivi...Induced pluripotent stem (iPS) cell technology demonstrates that somatic cells can be reprogrammed to a pluripotent state by over-expressing four reprogramming factors.This technology has created an interest in deriving iPS cells from domesticated animals such as pigs,sheep and cattle.Moloney murine leukemia retrovirus vectors have been widely used to generate and study mouse iPS cells.However,this retrovirus system infects only mouse and rat cells,which limits its use in establishing iPS cells from other mammals.In our study,we demonstrate a novel retrovirus strategy to efficiently generate porcine iPS cells from embryonic fibroblasts.We transfected four human reprogramming factors (Oct4,Sox2,Klf4 and Myc) into fibroblasts in one step by using a VSV-G envelope-coated pantropic retrovirus that was easily packaged by GP2-293 cells.We established six embryonic stem (ES)-like cell lines in human ES cell medium supplemented with bFGF.Colonies showed a similar morphology to human ES cells with a high nuclei-cytoplasm ratio and phase-bright flat colonies.Porcine iPS cells could form embryoid bodies in vitro and differentiate into the three germ layers in vivo by forming teratomas in immunodeficient mice.展开更多
OBJECTIVE: To assess the effectiveness of violateoil from Blumea Balsamifera(L.) DC. leaves(BB oil)on wound healing in mice.METHODS: Undiluted BB oil and its diluted solutions with olive oil to 1/5 and 1/10 to yield B...OBJECTIVE: To assess the effectiveness of violateoil from Blumea Balsamifera(L.) DC. leaves(BB oil)on wound healing in mice.METHODS: Undiluted BB oil and its diluted solutions with olive oil to 1/5 and 1/10 to yield BB oil1/5and BB oil1/10 were applied to the wounded skin before wound healing conditions were assessed by healing rate, histopathology, and contents of collagen, hydroxyproline, and Neuropeptide Substance P(SP). All above results were compared with the efficacies of the control, pure olive oil, basic fibroblast growth factor(BFGF), and cream of Jing Wan Hong(JWH).RESULTS: BB oil1/5and BB oil1/10 improved wound contraction and closure. Histopathology study further confirmed a desirable histological organization of wound tissues. BB oil1/5and BB oil1/10 reduced the number of inflammatory cells, increased wound-healing rates, and significantly increased the hydroxyproline content. Both BB oil1/5and BB oil1/10 improved formation of collagen, and reduced the frequency of fibroblasts. Moreover, BB oil1/5and BB oil1/10 markedly promoted SP expression. However, undiluted BB oil may induce skin thickening and hardening, inhibite collagen synthesis and delay complete skin wound healing.CONCLUSION: The BB oil1/5and BB oil1/10 promoted capillary regeneration, blood circulation, collagen deposition, granular tissue formation, epithelial deposition, and wound contraction. The mechanism underlying the action might be related to induction of SP secretion, and the proliferation and differentiation of mesenchymal cells.展开更多
文摘Objective Intravenous administration of basic fibroblast growth factor (bFGF) is effective to reduce the volume of cerebral infract due to ischemia. This study was designed to investigate the molecular mechanism, especially the signal transduction pathways, involved in this protective role of bFGF. Methods Anoxia-reoxygenation treated atrocytes were used to study the role of mitogen-activated protein kinase/extracellular signal-regulated kinase kinase (MAPK/ERK kinase, MEK)-ERK signaling pathway after exogenous bFGF administration by Western blot. Electrophoretic mobile shift assay was used to detect the binding activity of early growth response factor-1 (Egr-1), an important transcription factor for endogenous bFGF. Results bFGF could protect some signal transduction proteins from the oxygen-derived free radicals induced degradation. ERK1/2 was activated and involved in Egr-1 binding activity enhancement induced by exogenous bFGF. Conclusion MEK-ERK MAPK cascade may be an important signal transduction pathway contributed to bFGF induced enhancement of Egr-1 binding activity in anoxia-reoxygenation injured astrocytes.
基金Supported by Bioreactor Important Special Item of 863-Program inthe "Eleventh Five-Year" Plan (No. 2007AA100503)Science and Technology Development Key Plan of Jilin Province( No.20070922)+1 种基金Cultivation Fund of Scientific and Technical Innovation Project Major Program of Higher Education Institutions ( No.70S018)Science and Technology Plan of Changchun City (No.06GG150)~~
文摘[ Objective] The study is to generate pharmaceutical protein via plant transgenic technique. [Methed] Using the cotyledons with petiole as transformation receptor, the fusion gene of rapeseed oil-body gene and bFGF was introduced into the rapeseed ( Brassica campestris L. ) by Agrobacterium tumefaciens-mediated transformation; meanwhile regeneration conditions of rapeseed were also optimized, and the regenerated resistant plantlets were detected by PCR and Southern blot. [ Result] This fusion gene had been integrated into rapeseed genome successfully, and the optimized conditions of transformation and regeneration were as follows: explants pre-culture for 2 d, co-culture for 3 d, bacteria solution OD600 for 0.3 and infection time for 5 min. [ Conclusion] The results laid a solid foundation for extraction, isolation and purification of protein in transgenic plant seeds.
基金Supported by The National Key Project of Scientific and Technical Supporting Programs of China, No. 2006BAI02A14National Natural Science Foundation of China, No. 30770996 and No. 81172310
文摘AIM: To examine fibroblast activation protein (FAP) expression in pancreatic ductal adenocarcinoma (PDAC) and to analyze its relationship with the clinicopathology of PDAC. METHODS: FAP expression was examined in 134 PDAC specimens by immunohistochemistry, and in four pancreatic cancer cell lines (SW1990, Miapaca-2, AsPC-1 and BxPC-3) by Western blotting assay. We also analyzed the association between FAP expression in PDAC cells and the clinicopathology of PDAC patients. RESULTS: The results showed that the FAP was expressed in both stromal fibroblast cells (98/134, 73.1%) and carcinoma cells (102/134, 76.1%). All 4 pancreatic cancer cell lines expressed FAP protein at different levels. Protein bands corresponding to the proteolytically active 170-kDa seprase dimer and its88-kDa seprase subunit were identif ied. Higher FAP expression in carcinoma cells was associated with tumor size (P < 0.001), fi brotic focus (P = 0.003), perineural invasion (P = 0.009) and worse clinical outcome (P = 0.0085). CONCLUSION: FAP is highly expressed in carcinoma cells and f ibroblasts in PDAC tissues, and its expression is associated with desmoplasia and worse prognosis.
基金Supported by Grants from the National Natural Scientific Foundation of China,No.81060184the Natural Foundation of Hainan Province of China,No. 30864,811201+2 种基金Program for New Century Excellent Talents in University of China,NCET-08-0657the National Basic Research Program of China,No.2010CB534909Hainan Provincial Key Scientific Project,No.061009
文摘AIM:To investigate the inhibitory role of toxicarioside A on the gastric cancer cell line human gastric cancer cell line(SGC-7901) and determine the underlying molecular mechanism.METHODS:After SGC-7901 cells were treated with toxicarioside A at various concentrations(0.5,1.5,4.5,9.0 μg/mL) for 24 h or 48 h,cell viability was determined by 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl2H-tetrazolium bromide assay,and the motility and invasion of tumor cells were assessed by the Transwell chamber assay.Immunofluorescence staining,reverse transcription polymerase chain reaction and Western blotting were performed to detect the expression of basic fibroblast growth factor(bFGF) and fibroblast growth factor receptor-1(FGFR1),and nuclear factorkappa B(NF-κB) activation was examined by electrophoretic mobility shift assay.RESULTS:The results showed that toxicarioside A was capable of reducing cell viability,inhibiting cell growth,and suppressing cell migration and invasion activities in a time-and dose-dependent manner in SGC-7901 cells.Further analysis revealed that not only the expression of bFGF and its high-affinity receptor FGFR1 but also the NF-κB-DNA binding activity were effectively blocked by toxicarioside A in a dose-dependent manner compared with the control group(P < 0.05 or P < 0.01).Interestingly,application of the NF-κB specific inhibitor,pyrrolidinedithiocarbamate(PDTC),to SGC-7901 cells significantly potentized the toxicarioside A-induced down-regulation of bFGF compared with the control group(P < 0.05).CONCLUSION:These findings suggest that toxicarioside A has an anti-gastric cancer activity and this effect may be achieved partly through down-regulation of NF-κB and bFGF/FGFR1 signaling.
文摘A paracrine regulation was recently proposed in human embryonic stem cells (hESCs) grown in mouse embryonic fibroblast (MEF)-conditioned media (MEF-CM), where hESCs spontaneously differentiate into autologous fibroblastlike cells to maintain culture homeostasis by producing TGF-β and insulin-like growth factor-lI (IGF-Ⅱ) in response to basic fibroblast growth factor (bFGF). Although the importance of TGF-β family members in the maintenance of pluripotency of hESCs is widely established, very little is known about the role of IGF-Ⅱ. In order to ease hESC cul- ture conditions and to reduce xenogenic components, we sought (i) to determine whether hESCs can be maintained stable and pluripotent using CM from human foreskin fibroblasts (HFFs) and human mesenchymal stem cells (hM- SCs) rather than MEF-CM, and (ii) to analyze whether the cooperation of bFGF with TGF-β and IGF-Ⅱ to maintain hESCs in MEF-CM may be extrapolated to hESCs maintained in allogeneic mesenchymal stem cell (MSC)-CM and HFF-CM. We found that MSCs and HFFs express all FGF receptors (FGFR1-4) and specifically produce TGF-β in response to bFGF. However, HFFs but not MSCs secrete IGF-Ⅱ. Despite the absence of IGF-Ⅱ in MSC-CM, hESC pluripotency and culture homeostasis were successfully maintained in MSC-CM for over 37 passages. Human ESCs derived on MSCs and hESCs maintained in MSC-CM retained hESC morphology, euploidy, expression of surface markers and transcription factors linked to pluripotency and displayed in vitro and in vivo multilineage developmental potential, suggesting that IGF-Ⅱ may be dispensable for hESC pluripotency. In fact, IGF-Ⅱ blocking had no effect on the homeostasis of hESC cultures maintained either on HFF-CM or on MSC-CM. These data indicate that hESCs are successfully maintained feeder-free with IGF-Ⅱ-lacking MSC-CM, and that the previously proposed paracrine mechanism by which bFGF cooperates with TGF-β and IGF-Ⅱ in the maintenance of hESCs in MEF-CM may not be fully extrapolated to hESCs maintained in CM from human MSCs.
基金supported by grants from State 863High-Technology Rand Project of China(2006AA09Z406,2006AA10A401)Taishan Scholar Project of Shan-dong Province
文摘A cell line, SHK, was derived from the kidney of spotted halibut Verasper variegates. The cell line was subcultured more than 40 passages in minimum essential medium (MEM) supplemented with fetal bovine serum (FBS) and 10 ng ml4 basic fibroblast growth factor (bFGF). Cell morphology from primary culture and subculture was observed continuously by microscopy. The SHK cell line consisted predominantly of fibroblast-like cells. The cell line was able to grow between 20℃ and 30℃ with the optimum growth at 24℃ and with a reduced growth between 12℃ and 20℃. The growth rate of the cells increased as the proportion of FBS increased from 10% to 20% at 28℃ with optimum growth at the concentration of 20%. The doubling time of the cells was determined to be 44.8 h. Chromosome analysis revealed that 52% of the SHK cells maintained a normal diploid chromosome number (2n=46). The cells were successfully transfected with green fluorescent protein (GFP) reporter plasmids and the expression of GFP gene in the cells indicated the possible utility of the cells in gene expression studies. The cells were infected by lymphosystis disease virus (LCDV) and found to be susceptible to the virus in cytopathic effect (CPE) observation. The infection was confirmed by PCR and electron microscopy experiments, which proved the existence of the viral particles in the cytoplasm of the virus-infected cells.
基金Supported by The National Natural Science Foundation Grant,No. 30860374
文摘AIM:To study the inhibition of tumor angiogenesis by 5,2,4'-trihydroxy-6,7,5'-trimethoxyflavone(TTF1) isolated from an extract of herbal medicine Sorbaria sorbifolia.METHODS:Angiogenic activity was assayed using the chick embryo chorioallantoic membrane(CAM) method.Microvessel density(MVD) was determined by staining tissue sections immunohistochemically for CD34 using the Weidner capillary counting method.The mRNA and protein levels of vascular endothelial growth factor(VEGF),vascular endothelialgrowth factor receptor 2(VEGFR2,Flk-1/KDR),basic fibroblast growth factor(bFGF),cyclo-oxygenase(COX)-2 and hypoxia-inducible factor(HIF)-1α were detected by quantitative real-time polymerase chain reaction and Western blotting analysis.RESULTS:The TTF1 inhibition rates for CAM were 30.8%,38.2% and 47.5% with treatment concentrations of 25,50 and 100 μg/embryo × 5 d,respectively.The inhibitory rates for tumor size were 43.8%,49.4% and 59.6% at TTF1 treatment concentrations of 5,10,and 20 μmol/kg,respectively.The average MVD was 14.2,11.2 and 8.5 at treatment concentrations of 5 μmol/kg,10 μmol/kg and 20 μmol/kg TTF1,respectively.The mRNA and protein levels of VEGF,KDR,bFGF,COX-2 and HIF-1α in mice treated with TTF1 were significantly decreased.CONCLUSION:TTF1 can inhibit tumor angiogenesis,and the mechanism may be associated with the down-regulation of VEGF,KDR,bFGF,HIF-1α and COX-2.
文摘The aim of this study was to develop a synthetic medium for the in vitro culture of bovine embryos, using various growth factors and cytokines (GF-CYK): insulin-like growth factorl (IGF-Ⅰ), insulin-like growth factorⅡ (IGF-Ⅱ), basic fibroblast growth factor (bFGF), leukemia inhibitory factor (LIF), granulocyte-macrophage colony stimulating factor (GM-CSF) and transforming growth factor beta Ⅰ (TGF-β1) + hyaluronan (HA) + recombinant albumin (RA). The embryos were cultured in synthetic oviduct fluid (SOF) supplemented with: treatment 1 (T1): bovine serum albumin (BSA) + insulin, transferrin and selenium (ITS) (control); or treatment 2 (T2): GF-CYK + HA + RA. The blastocyst rates were not significantly different between TI and T2, at seven days post fertilization (dpf) (28.9% ± 2.4% and 31.8% ±2.2%), and at 8 dpf (36.5% ±2.4% and 39.1% ±1.9%), respectively (P 〉 0.05). The total cell number (TCN) was significantly higher with T2 than that with T1 at 7 dpf(164.9 ±5.3 and 149.7 ±4.0) and 8 dpf (182.7 ±6.4 and 165.0 ±5.5) (P 〈 0.05). The blastocyst diameter obtained with T2 was significantly greater (P 〈 0.05) than with T1 at 7 dpf (173.3 μm ±4.9 μm and 157.2μm ±4.1 μm, respectively), however, no significant differences were observed at 8 dpf (190.3 μm 5.2 μm and 179.7 μm ± 5.3 μm, respectively). In conclusion, the synthetic medium (T2) shows a comparable development rate to the control medium and improves the blastocyst diameter and the TCN.
文摘Objective: to observe expression of vascular endothelial growth factor-C (VEGF-C) and alkaline fibroblast growth factor (b-FGF) in tissues of lung cancer, and its relationship with cancer metastasis.Methods: to adopt immunohistochemical methods, analysis of 60 cases of lung tissue expression of VEGF-C and b-FGF in the situation.Result: positive rates of VEGF-C and b-FGF in lung cancer are respectively 56.67% and 63.33%; expression of VEGF-C and b-FGF in lung cancer is not related to pathological grades, pathologic stages or ages of patients (P 〉 0.05),but closely related to TNM stages and existence of lymph node metastasis (P 〈 0.01). IMVD in center of lung cancer tissues is obviously higher than surrounding area, with significant differences (P 〈 0.01). Conclusion: expression of VEGF-C and b-FGF is related to lung cancer progress.
基金supported partially by the National Grant for Outstanding Young Researchers (No.39525024) the Major State Basic Development Program (No.G1999054204).
文摘OBJECTIVE: To evaluate the safety and efficacy of topical application of recombinant bovine basic fibroblast growth factor (rbFGF) on the healing of chronic cutaneous wounds. METHODS: Twenty-eight patients with thirty-three chronic cutaneous wounds resulting from trauma, diabetes mellitus, pressure sore and radiation injuries were enrolled in this prospective, open-label crossover trial. Prior to treatment with rbFGF, all wounds failed to heal with conventional therapies within 4 weeks. All wounds were locally treated with rbFGF at a dose of 150 AU/cm(2). Healing time and the quality of wounds were used to evaluate the efficacy of the treatment. RESULTS: Healing of all chronic wounds was expedited. During the study, eighteen wounds completely healed within 2 weeks, four healed within 3 weeks, and another eight completely healed within 4 weeks. Only three wounds failed to heal within 4 weeks, but healed at 30, 40 and 42 days after treatment with rbFGF. Thus, compared with conventional therapies, the effective rate of rbFGF treatment within 4 weeks was 90.9%. Histological assessment showed more abundant capillary sprouts or tubes and that fibroblasts were differentiated in wounds treated with rbFGF. No adverse side effects related to basic fibroblast growth factor were observed. CONCLUSIONS: Our results indicate that rbFGF could be used to accelerate healing in chronic wounds. It is our belief that this may be a more effective method of chronic wound management.
文摘OBJECTIVE: To detect the expression of basic fibroblast growth factor (bFGF) in human ocular tissues, and to assess the effect of bFGF on the proliferation of human cataract lens epithelial cells (LECs) and its correlation with age. METHODS: Enucleated eyes were subjected to immunostaining for bFGF protein. Human cataract LECs were cultured in vitro, and treated with bFGF for 48 hr. Proliferation was estimated by the positive area ratio of proliferating cell nuclear antigen (PCNA) in immunohistochemistry. RESULTS: bFGF protein was found in various human ocular tissues. bFGF stimulated human cataract LEC proliferation, and there was an age-related decrease in responsiveness of human cataract LECs to bFGF (P
文摘Objective The present study is to observe in vitro the proliferation ability of the muscle cells from permanent myopathy (PM) patients of nomokalaemic periodic paralysis (normKPP), which is caused by mutations of Metl592Val in the skeletal muscle voltage gated sodium channel (SCN4A) gene on chromosome 17q23.1. We also evaluate the possible effect of the foreign basic fibroblast growth factor (bFGF) in preventing and curing PM. Methods The gastrocnemius muscle cells were taken from two male patients with PM of the same Chinese family with Metl592Val mutation of SCN4A, determined by gene screening. Four male patients suffering from the skeletal injury without PM were taken as control. All preparations were protogenerationally cultured in vitro. Proliferation of the cultured preparations was measured by MTT. Activities of the lactic dehydrogenase (LDH), creatine kinase (CK), and protein content in these cells were also detected. The effects of bFGF with different doses (10 ng/mL, 20 ng/mL, 40 ng/mL, 80 ng/mL, 120 ng/mL and 160 ng/mL) on the above mentioned parameters were also evaluated. Results Cells from both PM and control subjects were successfully cultured in vitro. The cultivation of the muscle cells from PM patients in vitro was not yet seen. Results indicated the obvious stimulation of bFGF on cell proliferation, activities of LDH and CK, protein synthesis, in a dose dependent manner. The optimal dose of bFGF was 120 ng/mL (P〈0.05), beyond which greater dose caused a less effect. The effect of bFGF on 160 ng/mL was stronger than that on 80 ng/mL, but there was no significant difference (P〉0.05). Conclusion Myoblastic cells from patients with PM had a weaker ability of developing into the myotubules, thus they were unable to perform effective regeneration, which resulted in a progressive necrosis. The exogenous bFGF could promote the division and proliferation of the muscle cells in vitro. These results shield a light on bFGF's potential role in preventing and treating PM.
基金supported by National Natural Science Foundation of China(81101369,81071450)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,Ministry of Education of China(to Shi Qin),Ph.D.Programs Foundation of State Education Ministry(20113201110013)+1 种基金Jiangsu Provincial Special Program of Medical Science(BL2012004,BK2011264)Jiangsu Province’s Key Provincial Talents Program(RC2011102)
文摘Nerve conduit is one of strategies for spine cord injury(SCI)treatment.Recently,studies showed that biomaterials could guide the neurite growth and promote axon regeneration at the injury site.However,the scaffold by itself was difficult to meet the need of SCI functional recovery.The basic fibroblast growth factor(bFGF)administration significantly promotes functional recovery after organ injuries.Here,using a rat model of T9 hemisected SCI,we aimed at assessing the repair capacity of implantation of collagen scaffold(CS)modified by collagen binding bFGF(CBD-bFGF).The results showed that CS combined with CBD-bFGF treatment improved survival rates after the lateral hemisection SCI.The CS/CBD-bFGF group showed more significant improvements in motor than the simply CS-implanted and untreated control group,when evaluated by the 21-point Basso-Beattie-Bresnahan(BBB)score and footprint analysis.Both hematoxylin and eosin(H&E)and immunohistochemical staining of neurofilament(NF)and glial fibrillary acidic protein(GFAP)demonstrated that fibers were guided to grow through the implants.These findings indicated that administration of CS modified with CBD-bFGF could promote spinal cord regeneration and functional recovery.
基金Supported by 5451 project of Health Science and Technology of Henan Province(No.201108)
文摘OBJECTIVE: To investigate the effects and mecha- nisms of Erbanxiao solution in inhibiting tumor an- giogenesis. METHODS: We observed the effects and mecha- nisms of Chinese medicines on inhibiting tumor an- giogenesis and studied the theories and results of treatment. Sixty patients with lung cancer were ran- domized into two groups (n=30). Patients in the control group were given compound Kushen injec- tion, and patients in the treatment group were giv- en Erbanxiao solution. The effect of Erbanxiao solu- tion on vascular endothelium growth factor (VEGF), basic fibroblast growth factor (bFGF), and tumor ne- crosis factor-α (TNF-α) was observed. RESULTS: The effective rate of the treatment group was 60% while the control group was 36%. There was a significant difference between the twogroups (P〈0.05). VEGF, bFGF, and TNF-a levels of the two groups were significantly different before and after treatment (P〈0.01). These Traditional Chi- nese Medicines significantly inhibited tumor angio- genesis, possibly by changing levels of VEGF, bFGF, and TNF-α. CONCLUSION: It is necessary to further explore the potential of Traditional Chinese Medicine in the treatment of angiogenesis in tumor patients.
基金supported by the National High Technology Research and Development Program of China(2012AA020502)National Natural Science Foundation of China(81171457,81371687)+3 种基金Natural Science Foundation of Jiangsu Province of China(BK20130390)Natural Science Foundation of Nantong City(BK2012089)the Natural Science Research Program of Jiangsu Education Department(13KJB310014)the Priority of Academic Program Development of Jiangsu Higher Education Institutions and Natural Science Foundation of Nantong University(10Z014)
文摘Peripheral nerve functional recovery after nerve injury generally requires multiple growth factors by synergistic effect.However,the optical combination of multiple synergistic growth factors for axonal regeneration has been scarcely considered up to now.Meanwhile,the use of growth factors in promoting nerve regeneration was limited by its short biological half-life in vivo,its vulnerability to structure disruption or hydrolyzation,leading to loss of bioactivity.Herein,a novel polymeric nanoparticle delivery system composed of heparin andε-poly-L-lysine(PL)was prepared for control release of nerve growth factor(NGF)and basic fibroblast growth factor(bFGF).The nanoparticles were synthesized by polyelectrolyte complexation in aqueous solution at room temperature,followed by cross-linking with biological genipin.The obtained nanoparticles had a spherical shape,with a mean diameter of about 246 nm,and high growth factors encapsulation efficiency as well as good stability.NGF and bFGF were encapsulated in the nanoparticles and showed a continuous and slow release behavior in vitro.The bioactivities of the released growth factors were evaluated,and exhibited the synergistic effect.The controlled release of the dual synergistic growth factors would improve the treatment of peripheral nerve injury to mimic the natural cellular microenvironments.
基金supported by the National Basic Research Program of China (Grant Nos. 2009CB941003, 2011CBA0110 and 2011CBA01000)
文摘Induced pluripotent stem (iPS) cell technology demonstrates that somatic cells can be reprogrammed to a pluripotent state by over-expressing four reprogramming factors.This technology has created an interest in deriving iPS cells from domesticated animals such as pigs,sheep and cattle.Moloney murine leukemia retrovirus vectors have been widely used to generate and study mouse iPS cells.However,this retrovirus system infects only mouse and rat cells,which limits its use in establishing iPS cells from other mammals.In our study,we demonstrate a novel retrovirus strategy to efficiently generate porcine iPS cells from embryonic fibroblasts.We transfected four human reprogramming factors (Oct4,Sox2,Klf4 and Myc) into fibroblasts in one step by using a VSV-G envelope-coated pantropic retrovirus that was easily packaged by GP2-293 cells.We established six embryonic stem (ES)-like cell lines in human ES cell medium supplemented with bFGF.Colonies showed a similar morphology to human ES cells with a high nuclei-cytoplasm ratio and phase-bright flat colonies.Porcine iPS cells could form embryoid bodies in vitro and differentiate into the three germ layers in vivo by forming teratomas in immunodeficient mice.
基金the Fundamental Scientific Research Funds for Chinese Academy of Tropical Agricultural Sciences-Tropical Crops Genetic Resources Institute[The Evaluation and Mechanism Research for the Treatment of Ainaxiang(Herba Blumeae Balsamiferae)Oil on Skin Burns Based on Cytokines,No.#1630032014016]the Natural Science Fund of Hainan Province[the Evaluation and Mechanism Research of Ainaxiang(Herba Blumeae Balsamiferae)Oil on Healingand Repairing of Skin Wounds,No.#312022]the Natural Science Fund of China(Study on Variety Classification of"Nalong"and It's Ethanopharmacology of Li in Hainan,No.#81374065)
文摘OBJECTIVE: To assess the effectiveness of violateoil from Blumea Balsamifera(L.) DC. leaves(BB oil)on wound healing in mice.METHODS: Undiluted BB oil and its diluted solutions with olive oil to 1/5 and 1/10 to yield BB oil1/5and BB oil1/10 were applied to the wounded skin before wound healing conditions were assessed by healing rate, histopathology, and contents of collagen, hydroxyproline, and Neuropeptide Substance P(SP). All above results were compared with the efficacies of the control, pure olive oil, basic fibroblast growth factor(BFGF), and cream of Jing Wan Hong(JWH).RESULTS: BB oil1/5and BB oil1/10 improved wound contraction and closure. Histopathology study further confirmed a desirable histological organization of wound tissues. BB oil1/5and BB oil1/10 reduced the number of inflammatory cells, increased wound-healing rates, and significantly increased the hydroxyproline content. Both BB oil1/5and BB oil1/10 improved formation of collagen, and reduced the frequency of fibroblasts. Moreover, BB oil1/5and BB oil1/10 markedly promoted SP expression. However, undiluted BB oil may induce skin thickening and hardening, inhibite collagen synthesis and delay complete skin wound healing.CONCLUSION: The BB oil1/5and BB oil1/10 promoted capillary regeneration, blood circulation, collagen deposition, granular tissue formation, epithelial deposition, and wound contraction. The mechanism underlying the action might be related to induction of SP secretion, and the proliferation and differentiation of mesenchymal cells.