BACKGROUND: Heart valve tissue engineering is aimed to construct heart valve grafts with the physiological function and biological activity by using engineering and life science principles and methods, but still in the animal experiment stage.OBJECTIVE: To summarize the commonly used tissue engineered heart valve, and to evaluate the reliability of different types of heart valve biomaterials.METHODS: Using "biological materials, heart valve, scaffolds, reviews, tissue engineering" in Chinese as the key words, a computer retrieval was performed for articles published from January 2000 to December 2010. Articles regarding the biomaterials in tissue engineered heart valve were included; the duplicated research or meta-analysis were excluded.RESULTS AND CONCLUSION: A total of 20 papers about the biomaterials and tissue engineering heart valve were screened out. Due to the superior biocompatibility and three-dimensional conformation, natural scaffold materials exhibit unparalleled bionic property compared with other materials. Synthetic biodegradable polymer materials with good mechanical properties and controllability has thus been highly favored by researchers, while the composite scaffold materials of natural materials and polymer materials provides a new strategy and direction for the investigations of tissue engineered heart valve, and has broad application prospects.

BACKGROUND: Our previous studies have demonstrated that cryopreserved bone marrow stromal cells (BMSCs) still maintain high survival rate, cell proliferation and osteogenic differentiation potentials after thawing. However, this result needs confirmed in vivo environment. OBJECTIVE: To explore the effects of cryopreserved BMSCs and collagenic membrane BME-10X complex on type Ⅰ collagen synthesis in vivo. METHODS: Beagle dog BMSCs were cultured in vitro and cryopreserved for 12 months, which were thawed and prepared complexes with collagenic membrane. The complexes were cultured with mineralization induction medium or normal medium for 5 days, followed by implanting into nude mice. The specimens were harvested and analyzed by gross observation, histopathological and immunohistochemistry at 4 weeks after implantation. The collagenic membrane cultured with mineralization induction medium served as controls. RESULTS AND CONCLUSION: In the control group, the boundary of collagenic membrane was distinctly, without cell growth around boundary or intra collagenic membrane, additionally, there was little type Ⅰ collagen. In the non-induction group, cells grew into collagenic membrane, trabes-like collagen formed, and type Ⅰ collagen distribution increased at 4 weeks. In the induction group, scaffold degraded, more cells grew, and plenty of collagen formed osteoid-like tissues. The distribution of typeⅠcollagen was obviously increased than that of other groups. The findings demonstrated that cryopreserved BMSCs possess strong osteogenic differentiation potentials after proliferation and induction combined with collagenic membranes in vitro.

BACKGROUND: Mesenchymal stem cells are the stem cells that possess the capability for self-renewal and multi-directional differentiation. Umbilical cord is the tissue outside the embryos and would be fallen off after parturition. In addition, it has wide source and no ethical restriction, so it is promising to be the first choice for mesenchymal stem cells. OBJECTIVE: To detect the surface markers CD29, CD44, CD49e, CD73, CD90, CD34, CD45, and CD271 of human umbilical cord-derived mesenchymal stem cells (hUCMSCs) prior to and after cryopreservation and resuscitation. METHODS: After isolation and culture, morphology of the primary, P4 and P8 hUCMSCs was observed prior to cryopreservation and after resuscitation. Surface markers CD29, CD44, CD49e, CD73, CD90, CD34, CD45, and CD271 of primary, P4, and P8 hUCMSCs were detected through the use of flow cytometry prior to cryopreservation and after resuscitation RESULTS AND CONCLUSION: hUCMSCs prior to cryopreservation and hUCMSCs of different passages after resuscitation present the same phenotype, i.e., positive for CD29, CD44, CD49e, CD73, and CD90, and negative for CD34, CD45, CD271. These findings suggest that primary hUCMSCs do not present changes in surface markers after cryopreservation and resuscitation.

BACKGROUND: CpG oligonucleotide has been shown to strengthen the function of peripheral blood mononuclear cells (PBMCs), but its effects on type 1 diabetes mellitus has been rarely reported. OBJECTIVE: To investigate the effects of CpG oligonucleotide on the expression of interferon γ (IFN-γ), interleukin (IL) -12 and IL-10 in PBMCs in patients with type 1 diabetes mellitus versus healthy controls. METHODS: PBMCs were isolated from patients with type 1 diabetes mellitus and healthy controls and then cultured in RPMI-1640 with non-stimulator (control group) and CpG oligonucleotide (CpG oligonucleotide group), respectively. The mRNA expression of IFN-γ, IL-10, and IL-12 in PBMCs was detected by reverse transcription-polymerase chain reaction. RESULTS AND CONCLUSION: mRNA expression of IFN-γ and IL-10 was significantly lower in patients with type 1 diametes mellitus than in healthy controls (P < 0.01). In the CpG oligonucleotide group, the mRNA expression of IFN-γand IL-12 was significantly higher than in the healthy control group (P < 0.01), but the mRNA expression of IL-10 was similar to that in the healthy control group (P > 0.05). These findings demonstrated that CpG oligonucleotide can promote the production of IFN-γ and IL-12 in PBMCs of type 1 diametes mellitus.

BACKGROUND: The central position of dendritic cells (DCs) has aroused increasing attention due to strong antigen presentation capability in anti-tumor. However, how to obtain enough functional DCs and reports regarding immunomodulator with low toxicity are few. OBJECTIVE: To investigate the effect of mycobacterium phlei F.U.36 (Utilins) on the proliferation and maturity of DCs derived from human umbilical cord blood in vitro.METHODS: The mononuclear cells were isolated from human umbilical cord blood using Ficoll-Hypaque method and cultured with Utilins, cytokine (human recombinant granulocyte/macrophage colonystimulating factor + recombinant human tumor necrosisfactor-α + recombinant human interleukin-4), or combination cytokine + Utilins, respectively. In addition, cells cultured with RPMI-1640 served as controls. Morphological features and growth of DCs were observed by an inverted microscope. Thephenotype changes of DCs, such CD1a and HLA-DR, were detected by flow cytometry at 9 days after culture. Moreover, DCs were stained by Wright-Giemsa and observed under oil lens. RESULTS AND CONCLUSION: Typical DCs with high expressions of CD1a and HLA-DR were obviously detected in all experimental groups except the control group. The positive rates of CD1a and HLA-DR in the Utilins group were higher than those in the control group, but lower than the cytokine group (P < 0.05). The HLA-DR positive rate of the combination group was higher than that of the cytokine group (P < 0.05). The results revealed that, Utilins can not only promote the proliferation of DCs derived from human umbilical cord blood in vitro but also cooperate with cytokines to induce the maturity of DCs.

BACKGROUND: How to establish a stable in vitro culture system, including location of corneal limbal epithelial stem cells, in vitro sample harvest, in vitro culture, vector selection, as well as identification methods, play a key role in corneal limbal epithelial stem cells culture. OBJECTIVE: To culture the isolated rabbit corneal limbal epithelial stem cells and to identify the biological properties of cultured cells. METHODS: The primary rabbit cornel limbal epithelial stem cells were isolated and cultured with tissue inoculation using human amniotic membrane as vector. The growth features of cells were observed under an inverted microscope. The morphology of cells was observed by hematoxylin-eosin staining and a scanning electron microscope. Furthermore, the monoclonal antibody AE5 and P63 two-step immunohistochemical staining were used to identify limbal epithelial stem cell protein expression. RESULTS AND CONCLUSION: The rabbit corneal limbal epithelial stem cells could be successfully cultured and maintained a relatively high value-added potential in vitro. Rabbit corneal limbal epithelial stem cells cultured on the amniotic membrane pull netted cellular layer. The AE5 monoclonal antibody positive rate of primary cultured cells was about 5% and P63 monoclonal antibody positive up to 90%. AE5-positive rate increased and P63-positive rate decreased with the increase in the number of subculture. The rabbit limbal epithelial stem cells can be successful culture and amplified on human amniotic membrane in vitro by limbal tissue culture method. The cultured cells maintain the characteristics of corneal epithelial cells. The rabbit corneal limbal epithelial stem cells can form grafts on the amniotic membrane.

BACKGROUND: Experiment suggests that the active component of Danggui Buxue decoction, i.e. polysaccharides, can significantly promote proliferation and differentiation of hematopoietic stem cells and hematopoietic progenitor cells, and regulate hematopoietic microenvironment.OBJECTIVE: To investigate the effect of serum containing Danggui Buxue decoction on granulocyte colony-stimulating factor (G-CSF) and interleukin-3 (IL-3) secretion in mice bone marrow stromal cells (BMSCs). METHODS: BMSCs were isolated and cultured in 96-well culture plate. BMSCs morphology and growth were observed by phase contrast microscopy. The cells were divided into four groups and cultured with different concentrations of the serum containing Danggui Buxue decoction. MTT method was used to observe the proliferation of BMSCs, and ELISA method was used to observe the expression level of G-CSF and IL-3. RESULTS AND CONCLUSION: Serum containing Danggui Buxue decoction significantly promoted BMSCs proliferation, and increased the expression level of G-CSF and IL-3 secreted from BMSCs in a dose-dependent manner. Notably, serum containing equivalent dose drugs significantly promoted BMSCs proliferation, and G-CSF and IL-3 expression compared with other groups. Higher concentration weakens cell proliferation and secretion effects.

BACKGROUND:n mandibular posterior dental implantation,injury to the inferior alveolar nerve sometimes occurs because of mandibular canal going across mandibular body.This restricts the use of dental implantation at this site.Therefore,it is essential to understand the anatomic structure of inferior alveolar nerve canal in mandibular posterior dental implantation.OBJECTIVE:To observe the intramandibular course of and anatomic structure of inferior alveolar nerve canal.METHODS:Fifteen adult complete mandible specimens with teeth and 4 fresh mandible arterial infusion specimens were researched.All the specimens had complete dentition and there were no obvious absorption in alveolar bone.The course of inferior alveolar nerve canal and its dimension including transverse and longitudinal diameters of mandibular canal and the distance between mandibular canal and mandible each side (superior,inferior,buccal and lingual side) were measured in 15 adult mandibles with teeth.The relationship between blood vessels and nerve of the canal was observed in 4 fresh arterial infusion specimens.RESULTS AND CONCLUSION:The distance between the medial border of the mandibular canal and the lingual wall was shorter than that of the lateral wall of the mandibular canal to the buccal wall (P < 0.01);The length from the upper wall of mandibiular canal to the top of the alveolar ridge was longer than that of the inferior border of the mandibular canal to the inferior border of the mandible (P < 0.01).The longitudinal diameter was smaller than the transverse diameter (P < 0.05),namely,the cross section of the mandibular canal was an ellipse with a longer longitudinal diameter.There was no significant difference between the transverse and longitudinal diameters of the canal in the anterior and posterior teeth region of the mandible.The inferior alveolar nerve and its associated blood vessels were located within a nervous vascular bunch in the mandibular canals.In every fresh specimen the blood vessels lay above the nerve.There were small branches of blood vessels surrounding thenerve.The mandibular canal ran towards the lingual side and was close to the inferior margin of the mandible.

BACKGROUND: Cerebral ischemia-reperfusion injury can result in irreversible neuronal function loss, whereas intrathecal administration of analgesia and neuroprotective drugs has been frequently used in the clinic. The animal models undergoing intrathecal administration of neuroprotective substances after cerebral injury are the basis of studies on the effects of neuroprotective substances.OBJECTIVE: To establish animal models of global cerebral ischemia combined with intrathecal catheterization for drug admistration. METHODS: Global cerebral ischemia was induced by four-vessel occlusion method and intrathecal catheterization was performed. Rats were randomly assigned to three groups with 10 rats per group: sham-surgery, model, and huwena toxin-Ⅰ (HWTX-Ⅰ). Rat models of global cerebral ischemia were established and intrathecal catheterization for drug administration was performed in the model and HWTX-Ⅰ groups. After model establishment, rats from the HWTX-Ⅰ group received HWTX-Ⅰ(1.0 μL/kg), and rats from the model group received the same amount of physiological saline. At 4 days after ischemia/reperfusion, Nissl staining was performed to observe the morphological changes of pyramidal neurons in rat hippocampal CA1 region. RESULTS AND CONCLUSION: In the sham-surgery group, numerous pyramidal neurons were densely and orderly arranged, endochylema was blue-stained, and Nissl body staining was even. In the HWTX-Ⅰ group, pyramidal neurons were orderly arranged, sparsely distributed, and some neuronal bodies were atrophic and darkly stained. In the model group, pyramidal neurons were disorderly arranged, and sparsely distributed in the whole CA1 region; in addition, a large number of neurons were atrophic and darkly stained. There was a larger degree of morphological change of hippocampal CA1 region pyramidal neurons in the HWTX-Ⅰ group than in the model group. Results indicate that rat models of global cerebral ischemia combined with intrathecal catheterization were successfully established.

BACKGROUND: Previous studies have demonstrated that acidic fibroblast growth factor (aFGF) combined with partially deproteinized bone (PDPB) (aFGF/PDPB) well promotes avascularization in animals with early-stage avascular necrosis of the femoral head (ANFH), but the histological results remain unknown.OBJECTIVE: To observe the histological repairing effects of aFGF/PDPB on early-stage ANFH in rabbits. METHODS: New Zealand rabbits were established models of bilateral ANFH and were randomly divided into a blank group, a simple PDPB group, and an aFGF/PDPB group. PDPB and aFGF/PDPB bone were implanted into the PDPB and aFGF/PDPB group accordingly. The blank group did not receive any implantation. At 2, 4, and 8 weeks after surgery, all animals were sacrificed for histological examination to observe the osteogenesis by hematoxylin-eosin staining.RESULTS AND CONCLUSION: Defects were filled with granulation tissues and fibrous connective tissues, only a little osteoid tissue formed at the borderline in the blank group at the end of the 8th week. In the PDPB group, a little new bone and cavitas medullaris formed. At 8 weeks, lots of graft was absorbed and cavitas medullaris formed with more osteoplasts and myeloid cells in it. The osteogenesis in the aFGF/PDPB group was better than that of PDPB group in each time point. At 4 weeks, the transplanted cavity was filled with osteoid tissues, a lot of osteogenic precursor cells and osteoblasts could be seen. Plenty of micrangium was observed, and osteoid tissues began to rebuild. At 8 weeks, the graft was replaced by bone tissues, and cavitas medullaris were formed with lots of bone marrow cells in it. At the borderline of the bone trabecula, there were lots of osteoplast and little osteoclasts, which may play a role in bone remodeling. There were mature bone cells in bone lacuna. Results indicate that aFGF/PDPB has better repair effect on rabbit model of ANFH than that of simple PDPB.