[Calibration on chromone reference extract and application on quality control of Saposhnikoviae Radix].

The calibration of chromone reference extract(CRE) was conducted and a quality control method of Saposhnikoviae Radix(SR) was established based on CRE. Meanwhile, the quality control system of SR was improved and the feasibility of using reference extract as a substitute for single reference substance in quality control of Chinese medicine was discussed. In this study, the content of the prepared CRE was calibrated with prim-O-glucosylcimifugin, cimifugin, 4'-O-ß-D-glucosyl-5-O-methylvisamminol, and secO-glucosylhamaudol as indicators. Subsequently, an HPLC analytical method was developed to determine the content of four chromones in 20 batches of SR samples based on the CRE with known content as the standard substance. T-test was used for the comparison of the determination results of the two methods(single chemical component and CRE as reference substances, respectively), and the P values of prim-O-glucosylcimifugin, cimifugin, 4'-O-ß-D-glucosyl-5-O-methylvisamminol, and sec-O-glucosylhamaudol were 0. 16,0. 39, 0. 14, and 0. 42. The results demonstrated that there was no significant difference between the two methods. This study initially verified the feasibility that the CRE could be used as a substitute for single reference substance in quality control of SR. In conclusion,this study is expected to provide a scientific basis and a new research model for the application of reference extract in the quality control of Chinese medicine.

[Study on scrophulariaceae radix reference extract and its application in quality control of Scrophulariae Radix].

By establishing the preparation process of Scrophulariaceae Radix reference extract(SRRE) and calibrating it, we discussed its feasibility as a substitute for single reference substance in the quality control of Scrophulariae Radix. The SRREs were prepared by solvent extraction method and chromatographic separation technology, and then calibrated with the reference substances of harpagide, angoroside C and harpagoside. The HPLC content determination method of Scrophulariae Radixl was established with SRREs of the known content and the reference substances of harpagide, angoroside C and harpagoside respectively as the control ones. Then the content of three components in Scrophulariae Radix was determined, and the t-test method was used to compare the results of the two methods. With SRRE as references, harpagide, angoroside C and harpagoside were in a good linear relationship(r≥0.999 8) within each range, and the average recovery rate was 98.55% to 100.6%. The t-test results showed that the P values of two determination methods were 0.493, 0.155 and 0.171 for harpagide, angoroside C and harpagoside respectively, indicating no significant diffe-rence between the two methods of content determination. The SRRE can be used as a substitute for the reference in the quality control of Scrophulariaceae Radix. The SRRE can replace the corresponding reference substance for the quality control of Scrophulariae Radix. The results of this study provide new methods and new ideas for the quality evaluation of Scrophulariae Radix, and provide a scientific basis for the application of reference extracts in the quality research of traditional Chinese medicine.

[Construction of "2R network pharmacology" research method for effective components of traditional Chinese medicine based on "prediction of dominant components-screening of potential targets"].

Chinese traditional medicine compound is the main form of Chinese medicine clinical application. The elucidation of the effective components of traditional Chinese medicine is one of the key scientific issues to promote the modernization of traditional Chinese medicine. At present, there are many research ideas on the effective components of traditional Chinese medicine compounds. By analyzing the current status and existing problems of existing research ideas, the author proposes a "double reduction network pharmacology"(2 R network pharmacology) research method based on "prediction of dominant components-potential target selection". Chemical components with good properties were selected by ADMET property prediction technology, and compared with the blood components and target organ components to determine the dominant components with potential therapeutic effect, that is "reducing constituents"; the potential core regulatory pathway of traditional Chinese medicine compound was enriched by RNA-Seq technology combined with network database, and then the target of traditional Chinese medicine compound was mined based on the signal pathway, that is "reducing targets". To improve the efficiency and accuracy of effective component screening, the network relationship of "component target" was established by the related technology of network pharmacology. The purpose of this study is to provide practical research ideas and methods for clarifying the effective components of traditional Chinese medicine, revealing the law of compatibility of traditional Chinese medicine and clarifying the target of drug action.

Deciphering the effective combinatorial components from Si-Miao-Yong-An decoction regarding the intervention on myocardial hypertrophy.

ETHNOPHARMACOLOGICAL RELEVANCE: Si-Miao-Yong-An decoction (SMYAD), a classical traditional Chinese medicine (TCM) formula, has been used to treat various cardiovascular diseases in clinics. AIM OF THE STUDY: The aim of this study is to investigate the effective combinatorial components from SMYAD and its mechanism regarding the intervention on myocardial hypertrophy. MATERIALS AND METHODS: SMYAD constituents absorbed in rat plasma and heart were identified using UHPLC Q-Exactive-Orbitrap MS/MS. The identified constituents in SMYAD were further analyzed using ADMET (absorption, distribution, metabolism, excretion and toxicity) prediction and molecular docking. The effective constituents were identified using isoproterenol (ISO)-induced H9c2 cardiomyocyte hypertrophy, and neochlorogenic acid (NCA), chlorogenic acid (CA), cryptochlorogenic acid (CCA), isochlorogenic acid C (ICAC), angoroside C (AGDC), isochlorogenic acid A (ICAA), sweroside (SRD), and harpagide (HPD) in SMYAD extract were quantified by HPLC for compatibility. Finally, anti-hypertrophic activities of candidate effective combinatorial components, which were prepared according to the determined molar concentration ratio of effective constituents using reference substance solution, were analyzed using immunofluorescence staining and Quantitative real-time PCR. The expression levels of PI3Kα, p-ERK, p-Akt, Akt, p-mTOR, mTOR and HIF-1α were measured using Western blot. RESULTS: 32 prototypes of SMYAD were identified from plasma and heart tissue of rat. Combining with ADMET prediction, 31 dominant constituents were focused. Based on HIF-1 pathway identified in preliminary result, 17 targets were focused, which were used to dock with 31 constituents. 27 constituents were therefore hit as the potential effective constituents of SMYAD in inhibiting myocardial hypertrophy. Bioactivity evaluation showed that NCA, CA, CCA, ICAC, AGDC, ICAA, SRD, and HPD significantly inhibited the increase of H9c2 cell surface area induced by ISO. Except for ICAA and AGDC, the remaining 6 effective constituents, showing a certain inhibitory effect on ISO-induced ANP mRNA overexpression at high and low concentrations, participated in compatibility based on the molar concentration ratio determined by HPLC. Effective combinatorial components composed of the 6 effective constituents (effective combinatorial components ABC) showed significant inhibitory effect on the increase of cell surface area, and the overexpression of ANP and ß-MHC mRNA in H9c2 cells induced by ISO. Moreover, effective combinatorial components ABC significantly inhibited the protein overexpressions of p-Akt, p-mTOR and HIF-1α. Based on the results, we put forward the strategy of "Focusing constituents" and "Focusing targets" for the effective constituents research of TCM formula. CONCLUSION: Effective combinatorial components ABC composed of NCA, CA, CCA, ICAC, SRD and HPD from SMYAD inhibited ISO-induced cardiomyocyte hypertrophy and down-regulated expression of ANP and ß-MHC mRNA through the inactivation of Akt/mTOR/HIF-1α pathway.

[Identification of compounds in Lycii Cortex by UPLC-LTQ-Orbitrap-MS].

This experiment was performed to analyze and identify the chemical constituents of Lycii Cortex by UPLC-LTQ-OrbitrapMS. The analysis was performed on a Waters Xbridge Shield RP18( 4. 6 mm×250 mm,5 µm) column with the mobile phase of 0. 1%formic acid( A)-acetonitrile( B) under gradient conditions at a flow rate of 1. 0 m L·min-1 and the temperature maintained at 35 ℃ ．Electrospray ionization ion trap time-off light multistage mass spectrometry was applied for qualitative analysis under positive and negative ion modes. The results indicated that 55 compounds consisted of 39 phenolic amides,6 organic acids,3 cyclic peptides,2 coumarins and 5 others. In conclusion,an UPLC-LTQ-Orbitrap-MS method was established to qualitative analysis of Lycii Cortex in this study,and the fragmentation rules of phenolic amides were summarized,which provides a good foundation for further study of Lycii Cortex.

Tissue engineered esophagus by mesenchymal stem cell seeding for esophageal repair in a canine model.

PURPOSE: Acellular porcine small intestinal submucosa (SIS) has been successfully used for esophagoplasty in dogs. However, this has not led to complete epithelialization and muscular regeneration. We undertook the present study to assess the effect of tissue-engineered esophagus generated by seeding bone marrow mesenchymal stem cells (BMSCs) onto an SIS scaffold (BMSCs-SIS) in a canine model. METHODS: We cultured, passaged, and measured autologous BMSCs and myoblasts with cell proliferation and immunohistochemical assays. We labeled the third passage of BMSCs with PKH-26, a fluorescent dye, before seeded it onto the SIS. We resected canine cervical esophagus to generate a defect 5 cm in length and 50% in circumference, which we repaired with BMSCs-SIS or SIS alone. RESULTS: Four weeks later, barium esophagram demonstrated that esophageal lumen surface of the patch graft was smoother in the BMSCs-SIS group compared with the SIS group. Histological examination suggested a strong similarity between BMSCs and esophageal myoblasts in terms of morphology and function. Although both BMSCs-SIS and SIS repaired the esophageal defects, we noted complete re-epithelialization with almost no inflammation only in the former group. By 12 wk after the surgery, we observed long bundles of skeletal muscles only in the BMSCs-SIS group, where the microvessel density was also much greater. CONCLUSIONS: Bone marrow mesenchymal stem cells on an SIS scaffold can promote re-epithelialization, revascularization, and muscular regeneration. This approach may provide an attractive option for esophageal regeneration.

The poor osteoinductive capability of human acellular bone matrix.

Demineralized bone matrix (DBM) has extensive clinical use for bone regeneration because of its osteoinductive and osteoconductive aptitude. It is suggested that the demineralization process in bone matrix preparation is influential in maintaining osteoinductivity; however, relevant investigations, especially into the osteoinductivity of acellular bone matrix, are not often performed. This study addressed the osteoinductive capability of human acellular cancellous bone matrix (ACBM) after subcutaneous implantation in a rat model. The growth and osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (rBM-MSCs) seeded in this material were also studied. Without the demineralization process, the ACBM we obtained had an interconnected porous network and the micropores in the surface were clearly exposed. After the ACBM was subcutaneously implanted for 4 months, new osteoid formation was noted but not typical mature bone formation. rBM-MSCs grew well in the ACBM and kept a steady morphology after continuous culture for 28 days. However, no mineralized nodule formation was detected and the expression levels of genes encoding osteogenic markers were significantly decreased. These results demonstrated that human ACBM possess the structural features of native bone and poor osteoinductivity; nonetheless this material helped to preserve the undifferentiated phenotype of rBM-MSCs. Such insights may further broaden our understanding of the application of ACBM for bone regeneration and the creation of stem cell niches.

Preparation and characterization of decellularized tendon slices for tendon tissue engineering.

To develop a naturally derived tendon tissue engineering scaffold with the preservation of the native ultrastructure, tensile strength, and biochemical composition of the tendon extracellular matrix (ECM), decellularized tendon slices (DTSs) were prepared using repetitive freeze/thaw of the intact Achilles tendons, frozen section, and nuclease treatment. The DTSs were characterized in the native ultrastructure, mechanical properties, biochemical composition, and cytocompatibility. Histological examination and DNA quantification analysis confirmed that cells were completely removed from tendon tissue by repetitive freeze/thaw in combination with nuclease treatment 12 h. The intrinsic ultrastructure of tendon tissue was well preserved based on scanning electron microscopy examination. The tensile strength of the DTSs was retained 85.62% of native tendon slice. More than 93% of proteoglycans (fibromodulin, biglycan) and growth factors (TGF-ß1, IGF-1, VEGF, and CTGF) inherent in tendon ECM were preserved in the DTSs according to ELISA analysis. Furthermore, the DTSs facilitated attachment and repopulation of NIH-3T3 fibroblasts in vitro. Overall, the DTSs are sheet scaffolds with a combination of elemental mechanical strength and tendon ECM bioactive factors that may have many potential applications in tendon tissue engineering.

Hypoxia inhibits the spontaneous calcification of bone marrow-derived mesenchymal stem cells.

Bone marrow-derived mesenchymal stem cells (BM-MSCs) are the popular seed cells for regenerative medicine, and there has been a rapid increase in the number of BM-MSC-based clinical trials. However, the safety of these cells should also be closely studied. In this study, spontaneous calcification of BM-MSCs from rats was evaluated in normoxia (20% O(2)) without osteogenic medium after continuous culture for 21 days; obvious mineralized nodules were observed, which were positive for Alizarin Red, collagen-I (Col-I), osteocalcin (OC) and alkaline phosphatase (ALP), and mainly consisted of C, O and Ca elements. Interestingly, hypoxia (2% O(2)) significantly inhibited this spontaneous calcification. In addition, the ALP and calcium content of rBM-MSCs were sharply reduced. Based on RT-PCR results, the expression of osteogenic genes (Cbfa1/Runx2, Col-I, ALP, and OC) was reduced compared to that in normoxia. These results demonstrate a natural and unique characterization of rat BM-MSCs in normoxia after continuous culture and highlight the inhibiting effects of hypoxia. Finally, this study contributes to the information regarding the application of BM-MSCs in the regeneration of various tissues.

Sonic hedgehog enhances the proliferation and osteogenic differentiation of bone marrow-derived mesenchymal stem cells.

MSCs (mesenchymal stem cells) may be promising seed cells for tissue regeneration because of their self-renewal and multi-differentiation potential. Shh (sonic hedgehog) is involved in the skeletal formation during embryo development and skeletal regeneration. However, how Shh regulates the biological characteristics of BM-MSCs (bone marrow-derived MSCs) is poorly understood. We have investigated the effect of rShh-N (recombinant N-terminal Shh) on the proliferation and osteogenic differentiation of rBM-MSCs (rat BM-MSCs) in vitro. rBM-MSCs were treated with rShh-N at concentrations up to 200 ng/ml. Proliferation and colony-forming ability of rBM-MSCs were increased in a dose-dependent manner. rShh-N increased the ratio of cells in S and G2/M phase, as well as the number of Ki-67+ cells. In addition, ALP (alkaline phosphatase) activity and matrix mineralization were enhanced by 200 ng/ml rShh-N. Real-time PCR showed that rShh-N (200 ng/ml) up-regulated the expression of genes encoding Cbfa-1 (core-binding factor α1), osteocalcin, ALP and collagen type I in rBM-MSCs. This information reveals some potential of rShh-N in the therapeutics of bone-related diseases.

Population mutation scanning of human GHR by meltMADGE and identification of a paucimorphic variant.

Current studies of human genetic diversity are focused in two areas: first, detection of rare mutations in highly selected clinical cases; and second, in common single-nucleotide polymorphism (SNP) and haplotype effects in the general population. Less frequent SNPs and "paucimorphisms" remain underexplored, although lower frequency coding SNPs are more likely to have functional impact. We have developed a cost-efficient mutation scanning technology, meltMADGE, for population mutation scanning. Previous research in GHR has explored its role in extreme (-3 SD) growth retardation and, subsequently, "moderate" (-2 SD) growth retardation cases. Here, we describe meltMADGE assays for the entire coding region of GHR. As a first step we have established long polymerase chain reaction subbanks for GHR from 2423 unselected subjects and have applied meltMADGE scanning assays of exons 4 and 5 to these subbanks. A novel paucimorphism present at 439+30A>C (allele frequency: 0.0021) in intron 5 (location chr5:42,695,221 in GRCh37/hg19) was identified in 10 individuals, confirmed by sequencing and analysis made for major phenotypic effects. This approach is relevant to the deep sampling of populations for less frequent sequence diversity, some of which is expected to exert significant phenotypic effects.

MicroRNA expression in multiple myeloma is associated with genetic subtype, isotype and survival.

BACKGROUND: MicroRNAs are small RNA species that regulate gene expression post-transcriptionally and are aberrantly expressed in many cancers including hematological malignancies. However, the role of microRNAs in the pathogenesis of multiple myeloma (MM) is only poorly understood. We therefore used microarray analysis to elucidate the complete miRNome (miRBase version 13.0) of purified tumor (CD138+) cells from 33 patients with MM, 5 patients with monoclonal gammopathy of undetermined significance (MGUS) and 9 controls. RESULTS: Unsupervised cluster analysis revealed that MM and MGUS samples have a distinct microRNA expression profile from control CD138+ cells. The majority of microRNAs aberrantly expressed in MM (109/129) were up-regulated. A comparison of these microRNAs with those aberrantly expressed in other B-cell and T-cell malignancies revealed a surprising degree of similarity (~40%) suggesting the existence of a common lymphoma microRNA signature. We identified 39 microRNAs associated with the pre-malignant condition MGUS. Twenty-three (59%) of these were also aberrantly expressed in MM suggesting common microRNA expression events in MM progression. MM is characterized by multiple chromosomal abnormalities of varying prognostic significance. We identified specific microRNA signatures associated with the most common IgH translocations (t(4;14) and t(11;14)) and del(13q). Expression levels of these microRNAs were distinct between the genetic subtypes (by cluster analysis) and correctly predicted these abnormalities in > 85% of cases using the support vector machine algorithm. Additionally, we identified microRNAs associated with light chain only myeloma, as well as IgG and IgA-type MM. Finally, we identified 32 microRNAs associated with event-free survival (EFS) in MM, ten of which were significant by univariate (logrank) survival analysis. CONCLUSIONS: In summary, this work has identified aberrantly expressed microRNAs associated with the diagnosis, pathogenesis and prognosis of MM, data which will prove an invaluable resource for understanding the role of microRNAs in this devastating disease.

A multi-step method for preparation of porcine small intestinal submucosa (SIS).

Porcine small intestinal submucosa (SIS) has been widely used in repairing various tissues and organs. Despite this, some SIS products have the capacity to cause variable inflammatory responses after implantation resulting in severe adverse effects due to porcine cell existence. In this study, we described a multi-step method including mechanical disassociation, degrease, enzyme digestion, detergent treatment, freeze-drying and sterilization by irradiation for preparation of SIS. The efficacy of acellularization was evaluated by histological observation and the content of porcine immunoreceptor DAP12 gene. The change of growth factors contents within SIS accompanying with decellularization was quantitatively assessed by ELISA. Inflammatory reaction of SIS implanted subcutaneously in a rat was investigated. The histological examination revealed no remaining cells after enzyme digestion. Moreover, qPCR analysis demonstrated that the content of a porcine immunoreceptor gene DAP12 DNA in final SIS product (SISv) was only 1.05% of that in SIS samples (SISi) prepared by mechanical disassociation. Degrease with methanol/chloroform dramatically reduced the contents of VEGF, b-FGF, TGF-ß, and TNF-α within SISii, but further treatment could not significantly reduced the contents of growth factors. SIS implanted into rats showed that inflammatory cells was more accumulated surrounded to SISi at 1, and 2 weeks, but reduced in SISv samples. The degree of inflammatory reaction for SISv was significantly less than that of SISi.

Biomarkers in clinical medicine.

Biomarkers have been used in clinical medicine for decades. With the rise of genomics and other advances in molecular biology, biomarker studies have entered a whole new era and hold promise for early diagnosis and effective treatment of many diseases. A biomarker is a characteristic that is objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes or pharmacologic responses to a therapeutic intervention (1). They can be classified into five categories based on their application in different disease stages: 1) antecedent biomarkers to identify the risk of developing an illness, 2) screening biomarkers to screen for subclinical disease, 3) diagnostic biomarkers to recognize overt disease, 4) staging biomarkers to categorise disease severity, and 5) prognostic biomarkers to predict future disease course, including recurrence, response to therapy, and monitoring efficacy of therapy (1). Biomarkers can indicate a variety of health or disease characteristics, including the level or type of exposure to an environmental factor, genetic susceptibility, genetic responses to environmental exposures, markers of subclinical or clinical disease, or indicators of response to therapy. This chapter will focus on how these biomarkers have been used in preventive medicine, diagnostics, therapeutics and prognostics, as well as public health and their current status in clinical practice.

Characterization of MSCs from human placental decidua basalis in hypoxia and serum deprivation.

Recently, we reported that human PDB (placental decidua basalis) is an excellent source of MSCs (mesenchymal stem cells), meanwhile, PDB-MSCs could survive under hypoxia and serum deprivation. Herein, we investigated the proliferation, clonogentic efficiency, phenotypes, metabolic activity and cytokines secretion of PDB-MSCs in hypoxia and serum deprivation. PDB-MSCs were cultured in four groups: normoxia (20% O2) and complete medium [10% FBS (foetal bovine serum)+DMEM-HG (Dulbecco's modified Eagle's medium-high glucose)], hypoxia and complete medium, normoxia and serum deprivation (0% FBS), and hypoxia and serum deprivation. After 96 h of culture in the above groups, PDB-MSCs maintain the phenotypes stably. Interestingly, hypoxia notably enhanced the proliferation, colony-forming potential and lactate/glucose ratio in complete medium, but suppressed the secretion of BMP-2 (bone morphogenetic protein-2) and bFGF (basic fibroblast growth factor), while it did not change the quantity of VEGF (vascular endothelial growth factor) and bFGF in serum deprivation. Although PDB-MSCs grew slowly and seldom formed a colony unit in hypoxia and serum deprivation, they possessed a moderate metabolism. In conclusion, our results indicate that PDB-MSCs appear to be promising seed cells for ischaemia-related tissue engineering.

Mesenchymal stem cells transplantation mildly ameliorates experimental diabetic nephropathy in rats.

BACKGROUND: Diabetic nephropathy is a common complication of diabetes mellitus. This study aimed to explore whether mesenchymal stem cells (MSCs) transplantation could attenuate diabetic nephropathy in experimental diabetic rats. METHODS: Sprague-Dawley rats received a single intraperitoneal injection of streptozotocin (STZ) (60 mg/kg). Diabetic rats were randomized to four groups: diabetes control group (DC), ciclosporin A group (CsA), MSC group, and MSC + CsA group (MSCA). Bone marrow mesenchymal stem cells were cultured, identified and labeled by 5-bromo-2'-deoxyuridine (BrdU) in vitro. Then they were transplanted to diabetic rats via introcardiac infusion. Ciclosporin A was administered daily at 5 mg/kg. At 1, 2, 4, 8 weeks after transplantation, random blood glucose, urine albumin/creatinine ratio (Alb/Cr), endogenous creatinine clearance rate and renal mass index were tested. Renal morphology and labeled cells were examined. RESULTS: Cultured MSCs expressed mesenchymal cell phenotype, and could be multidifferentiated to osteogenic and adipogenic cells. Labeled MSCs could be detected in the kidney of nephropathic rats, mainly in renal interstitium, but they did not propagate after engrafting in kidney. Over the course of the experiment, MSCA group showed a significant decrease in blood glucose compared with MSC group, CsA group and DC group (P < 0.05, respectively). The Alb/Cr in MSCA group and MSC group were significantly lower than CsA group and DC group (P < 0.05). And the Alb/Cr in MSCA group showed a significant decrease compared with MSC group (0.74 vs 0.84, P < 0.05). There was a significant difference in renal mass index between the MSCA group and DC group (5.66 vs 6.37, P < 0.05). No significant difference was found in creatinine clearance rate among 4 groups (P > 0.05). Treatment with MSC + CsA significantly ameliorated the morphology of diabetic kidney. CONCLUSION: MSC could mildly ameliorate diabetic nephropathy by decreasing blood glucose, Alb/Cr ratio and renal mass index.

Isolation of mesenchymal stem cells from human placental decidua basalis and resistance to hypoxia and serum deprivation.

Mesenchymal stem cells (MSCs) are the most promising seed cells for cell therapy and tissue engineering, which can be isolated from various sources of human adult tissues such as bone marrow and adipose tissue. However, cells from these tissues must be obtained through invasive procedures and sometimes the individual difference is hard to control. Hence, the search continues for an ethically conducive, easily accessible and controllable source of stem cells. We herein report the isolation of a population of stem cells from the human placental decidua basalis (termed as PDB-MSCs), a maternal portion of placenta. PDB-MSCs were further shown to express markers common to MSCs and positive for SSEA-1, SSEA-3, SSEA-4, TRA-1-60, TRA-1-81 and Oct-4. In order to facilitate the further utility in ischemic diseases, we tested the apoptosis of PDB-MSCs in hypoxia and serum deprivation, two components of ischemia in vivo. Taken together, our findings indicate that PDB-MSCs are resistant to hypoxia and serum deprivation, which may relate to Bcl-2.

Grafts of porcine small intestinal submucosa with cultured autologous oral mucosal epithelial cells for esophageal repair in a canine model.

The acellular porcine small intestinal submucosa (SIS) has been successfully used for esophagoplasty. However, it does not lead to a complete epithelialization in a canine model. A cellular component may be required for better reconstruction. The present study was undertaken to investigate the feasibility and effectiveness of the combination of SIS and autologous oral mucosal epithelial cells (OMECs) for esophageal reconstruction. The OMECs harvested from beagle dogs were cultured and propagated, and the 3rd passage cells were seeded on a single-layer SIS. Male beagle dogs were subjected to surgical resection to produce cervical esophageal defects (5 cm in length, 180 degrees in range). SIS with or without OMECs was patched on the esophageal defects. Barium esophagram, immunohistochemistry, and histology were performed to evaluate the therapeutic effectiveness. Four weeks after surgery, the histological examination showed a complete re-epithelialization and almost no inflammation in the SIS with OMECs group. But in the SIS group, only a partial epithelialization was observed along with inflammation. Eight weeks after surgery, the squamous epithelium was found to cover the entire graft surface in both groups; however, the muscular regeneration was observed in the SIS with OMECs, but not in the SIS group. The graft of SIS combined with autologous OMECs promotes re-epithelialization and muscular regeneration. It is an effective alternative method for esophageal repair.

[Effects of hypoxia on human placental decidua basalis-mesenchymal stem cells proliferation, apoptosis and VEGF expression.].

Human placental decidua basalis-mesenchymal stem cells (PDB-MSCs) are multipotent cells from the human term placenta, which are ethically conducive, easily accessible and high-yielding source. PDB-MSCs can differentiate into adipogenic, osteogenic and neurogenic cells under appropriate conditions, which may be an attractive and alternative source of seed cells for tissue engineering. To investigate the effect of hypoxia (1% O2) on human PDB-MSCs and the expression of cytokine, PDB-MSCs were isolated from human placenta by density gradient centrifugation and cultured in the Dulbecco's modified Eagle's medium-high glucose (DMEM-HG) containing 10% fetal bovine serum (FBS), and the fifth passage of PDB-MSCs were taken. PDB-MSCs were divided into 4 groups according to the concentrations of O2 and FBS: 20% O2, 10% FBS; 20% O2, 0% FBS; 1% O2, 10% FBS; 1% O2, 0% FBS. The proliferation and apoptosis of PDB-MSCs were detected by MTT and flow cytometric analysis at the time points of 6 h, 12 h, 24 h, 48 h, 72 h, and 96 h, respectively. Vascular endothelial growth factor (VEGF) released from PDB-MSCs was detected by enzyme-linked immunosorbent assay (ELISA) at the same time points. The results showed that hypoxia enhanced the proliferation of PDB-MSCs at 12 h under the condition of 10% FBS, while at 24 h under the condition of 0% FBS (P<0.01, n=3). In normoxia, the cells cultured in 10% FBS displayed a significant proliferation compared to those cultured in 0% FBS. However, in hypoxia, the number of cells cultured in 0% FBS (serum deprivation) increased significantly compared to that cultured in 10% FBS at 24 h and 96 h respectively (P<0.05, P<0.01, n=3). With the flow cytometric analysis of cell apoptosis under the condition of hypoxia and serum deprivation, we found that hypoxia and serum deprivation did not induce PDB-MSCs apoptosis (P>0.05, n=3). This conclusion may relate to the expression of VEGF which needs further research. In conclusion, the results obtained indicate that PDB-MSCs are able to bear hypoxia and serum deprivation, suggesting that PDB-MSCs can be used as seed cells for ischemia related tissue engineering.

[An experimental study on targeting suicide gene therapy for lung cancer with HSV-TK driven by hTERT promoter].

OBJECTIVE: To study the approach of targeting expression of suicide gene HSV-TK driven by human telomerase catalytic subunit (hTERT) promoter in lung cancer cells, and to investigate inhibitory effect of HSV-TK/GCV driven by hTERT promoter on proliferation of lung cancer cell line A549 in vitro and in vivo. METHODS: (1) Recombinant expression vectors of HSV-TK driven by hTERT promoter and SV40 promoter (pGL3-hTp-TK and pGL3-SV40-TK) were transfected into telomerase-positive human lung adenocarcinoma cell A549 and telomerase-negative human embryonic lung fibroblast cell MRC-5. The mRNA expression of TK gene was detected with RT-PCR method; (2) With the treatment of GCV, the proliferation of above transfected cells was investigated by MTT assay; Influence of GCV on apoptosis and cell cycle of these cells was evaluated with flow cytometry; (3) After the subcutaneously transplantation of A549 cells into nude mice, intra-tumor injection of plasmid-liposome as well as intra-peritoneal injection of GCV were performed to stUdy anti-tumor effects of pGL3-hTp-TK/GCV and pGL3-SV40-TK/GCV in vivo. RESULTS: (1) Enzyme digestion and PCR suggested that recombinant plasmids of pGL3-hTp-TK and pGL3-SV40-TK were successfully constructed; TK mRNA expression was detected in both A549 and MRC-5 cells transfected with pGL3-SV40-TK, also in A549 transfected with pGL3-hTp-TK, but not in MRC-5 transfected with pGL3-hTp-TK; (2) GCV showed significant inhibition effect on proliferation of A549 and MRC-5 transfected with pGL3-SV40-TK in vitro, also on that of A549 transfected with pGL3-hTp-TK, but not of MRC-5 transfected with pGL3-hTp-TK; With the treatment of GCV, apoptosis index (AI) of A549 cells transfected with pGL3-SV40-TK and pGL3-hTp-TK (21.58% and 23.19% respectively) increased significantly, compared with that of A549 transfected with pGL3-hTp and blank control; GCV enhanced the effects on AI in MRC-5 transfected with pGL3-SV40-TK (9.35%), but not with pGL3-hTp-TK (0.88%); (3) Inhibition ratio of pGL3-SV40-TK/GCV and pGL3-hTp-TK/GCV to transplanted tumor of A549 in nude mice (46.7% and 40.5% respectively) were significantly higher than that of negative control groups (9.7%, 14.3%, 7.0% and 8.0% respectively). CONCLUSION: TK gene driven by hTERT promoter could express selectively in lung cancer cell. Lung cancer cell could be specifically inhibited by HSV-TK/GCV driven by hTERT promoter in vitro and in vivo.