Quantum dots (QDs) are novel photo-stable semiconductor nanocrystals with wide excitation spectra and narrow, symmetrical emission spectra. QDs can be used as molecular probes by conjugating to a wide range of biological targets, including proteins, peptides and nucleic acids. It has been widely used in bio-labeling, fast detection and biological imaging. In this review, we focus on the applications of QDs in tissue engineering and its potential bio-safety issues.
Diagnostic Imaging ; Humans ; Molecular Probes ; Nucleic Acids ; Peptides ; Proteins ; Quantum Dots ; Tissue Engineering

This study was aimed to observe four kinds of kidney-tonification medicine, which were Epimedium, pso-ralen, Ligustrum lucidum, Polygonum with the active ingredient of icariin, psoralen, oleanolic acid, stilbene glucoside and their orthogonal compatibility. There were two kinds of non-kidney tonification medicine, which were Chuanx-iong and astragalus with the active ingredient of TMP and astragaloside. The observation was made on the regulatory role of rat bone marrow stem cells (BMSCs). A total of 65 SD rats were randomly divided into the normal control group, positive transformed control group, kidney-tonification compatibility group (including Group 1, Group 2, Group 3, Group 4, Group 5, Group 6, Group 7, Group 8, and Group 9), non-kidney tonification medicine control group (in-cluding TMP group and astragaloside group). Intragastric administration of medication was given to the kidney-tonifi-cation compatibility group and the non-kidney tonification medicine control group, once a day for 3 consecutive days. Intragastric administration of equal amount of normal saline was given to the normal control group and the posi-tive transformed control group. On the third day of intragastric administration, rats in each group were sacrificed. Serum containing medication was used in the culture of BMSCs for 6, 12, or 18 days. ELISA method was used to quantitatively detect the expression activity and content of BMP2 on the 6th, 12th, or 18th day, in order to evaluate the degree of bone cell differentiation degree. Real-time quantitative PCR method was used for detection of expression of Bmp2, Smad1, Smad4 mRNA in serum containing medication in the culture of BMSCs on the 18th day. The results showed that the kidney-tonification compatibility can improve the expression activity and content of BMP2 culture in vitro, with the peak on the 12th day. The kidney-tonification compatibility groups can upregulate expressions of Bmp2, Smad1, Smad4 mRNA. It was concluded that the active ingredient compatibility of kidney-tonification medicine can promote BMSCs. Its mechanism may be related to the upregulation of expression of Bmp2, Smad1, Smad4 mRNA, and the activity and content of Bmp2.

AIM: To study the alterations of heme oxygenase-1 mRNA in vascular smooth muscle cells(VSMC) induced by lipopolysaccharide(LPS) and the role of heme oxygenase(HO)/carbon monoxide(CO)pathway in the disorders of regulation of cardiovascular system by LPS. METHODS: LPS (final concentrations 10 mg/L,30 mg/L and 50 mg/L) was added in cultured VSMCs for 6 h respectively or 10 mg/L LPS for 9 h and 18 h. MDA content, LDH release and the rate of trypan blue uptake of VSMC were measured. HO-1 mRNA expression was examined by Northern Blot. RESULTS: VSMC HO-1 mRNA expression was increased gradually with the increasing of LPS concentration. When final concentration of LPS was 50 mg/L, the HO-1 mRNA expression of VSMC was increased by 176.7% compared with control. When LPS final concentration was 10 mg/L, the HO-1 mRNA expression increased gradually along with the culture time. When cultured for 18 h, the HO-1 mRNA expression of VSMC was increased by 195.6% compared with control. Only at LPS 50 mg/L for 6 h and 10 mg/L for 18 h, the rate of trypan blue uptake，MDA content and LDH release were significantly increased. CONCLUSION: LPS can induce the HO-1 mRNA expression of VSMC and that were dose-dependent and time-dependent. The inducible HO may play an important role in the pathogenesis of vascular system under LPS.

OBJECTIVE:To optimize the extraction and purification technology of total flavonoids from Engelhardia roxburghi-ana,and to establish the method for the content determination of 3 kinds of effective components. METHODS:Using the extrac-tion transfer rate of astilbin as index,single factor test was used to investigate extraction solvent,extraction method,volume frac-tion of percolation solvent ethanol,percolation material-liquid ration,soaking time before percolation and percolation rate of extrac-tion technology,and volume fraction of eluant ethanol in AB-8 resin purification technology. The contents of 3 effective compo-nents as astilbin,texifolin and engelitin in total flavonoids from E. roxburghiana were determined by HPLC. RESULTS:The opti-mal extraction technology was using 70% ethanol as extraction and percolation solvent,percolation extraction,soaking for 8 h be-fore percolation,percolation material-liquid ratio of 1∶16(g/ml),percolation rate of 30 ml/(min·kg). The purification technology was diluting the solution to 0.5 g (crude drug)/ml with water,ethyl acetate extraction,dissolved extract with 50% ethanol after evaporated to dryness,AB-8 resin for sampling,eluted with 50% ethanol,concentrating and drying. In verification test,extraction transfer rate of astilbin was more than 80%(RSD=0.42%,n=3). The contents of astilbin,taxifolin and engeletin in total flavo-noids from E. roxburghiana by purified were 57.94%,3.72% and 2.83%,respectively;the contents of 3 components accounted for 64.00% of total flavonoids. CONCLUSIONS:The extraction and purification technology is stable,rational and reliable;the content determination method of 3 effective components in total flavonoids of E. roxburghiana is accurate,simple and producible.

BACKGROUND:Adipose-derived mesenchymal stem cells are gaining widespread interest in the Achil es tendon tissue engineering and regeneration, and an enabling environment (oxygen concentration) for cellinduction and differentiation is particularly necessary.
OBJECTIVE:To co-culture adipose-derived mesenchymal stem cells with primary tenocytes in standard culture condition (20%O 2 tension) and in an atmosphere of reduced oxygen (2%O 2 tension) in order to determine whether the two conditions differ in their effect on tenogenic differentiation.
METHODS:Tenocytes were isolated via serial expansion in culture from several Sprague-Dawley rats’ Achil es tendons. Adipose-derived mesenchymal stem cells were purchased. After one passage, adipose-derived mesenchymal stem cells were indirectly co-cultured with tenocytes in standard culture condition (20%O 2 tension) and in an atmosphere of reduced oxygen (2%O 2 tension). Col agen 1, col agen 3, Tenomodulin, Thrombospondin-4, Scleraxis levels were compared for each culture condition at 7, 14 and 21 days fol owing co-culturing. Immunofluorescence staining was performed to evaluate production of col agen 1 and Thrombospondin-4.
RESULTS AND CONCLUSION:Fol owing indirect co-culturing, hypoxic differentiated adipose-derived mesenchymal stem cells expressed higher levels of tendon-related genes and proteins than normoxic controls, which suggest that oxygen levels can significantly affect tenogenic differentiation, and hypoxia is advantageous for efficient differentiation of adipose-derived mesenchymal stem cells in vitro for tendon tissue engineering.

AIM: To study the alterations of heme oxygenase-1 mRNA in vascular smooth muscle cells(VSMC) induced by lipopolysaccharide(LPS) and the role of heme oxygenase(HO)/carbon monoxide(CO)pathway in the disorders of regulation of cardiovascular system by LPS. METHODS: LPS (final concentrations 10 mg/L,30 mg/L and 50 mg/L) was added in cultured VSMCs for 6 h respectively or 10 mg/L LPS for 9 h and 18 h. MDA content, LDH release and the rate of trypan blue uptake of VSMC were measured. HO-1 mRNA expression was examined by Northern Blot. RESULTS: VSMC HO-1 mRNA expression was increased gradually with the increasing of LPS concentration. When final concentration of LPS was 50 mg/L, the HO-1 mRNA expression of VSMC was increased by 176.7% compared with control. When LPS final concentration was 10 mg/L, the HO-1 mRNA expression increased gradually along with the culture time. When cultured for 18 h, the HO-1 mRNA expression of VSMC was increased by 195.6% compared with control. Only at LPS 50 mg/L for 6 h and 10 mg/L for 18 h, the rate of trypan blue uptake,MDA content and LDH release were significantly increased. CONCLUSION: LPS can induce the HO-1 mRNA expression of VSMC and that were dose-dependent and time-dependent. The inducible HO may play an important role in the pathogenesis of vascular system under LPS. [

Objective:To detect the effect of microRNA-7 ( miR-7 ) knockdown on pathology in murine acute lung injury ( ALI) model,and preliminarily explore its significance.Methods:Murine ALI model was performed by intraperitoneal injection of Li-popolysaccharide (LPS) (10 mg/kg) into miR-7KD mice and wild-type (wild type,WT) mice respectively.Then,the pathologic injury of lung tissue were observed by HE staining.And total cell count of bronchoalveolarlavage(BAL) was calculated.The relative expression of related cytokines in lung tissue was analyzed by Real-time PCR assay.Furthermore,the changes on proportion of innate immune cells (γδT cell and F4/80 macrophages cell) and adaptive immune cell ( CD4+T cell and CD8+T cell) were analyzed by FACS.Meanwhile, the expression of CD62L and CD69,as well as the absolute number,in CD4+T cell were also analyzed.Results: Compared with WT mice,pathological damage in lung tissues was significantly alleviated in miR-7KD mice.Real-time PCR analysis showed that the relative expression of IL-6 was obviously reduced (P<0.01),conversely,relative expression of IL-4 and TGF-βwere obviously increased (P<0.05).Furthermore,the total cell number in BAL also reduced significantly (P<0.05).Importantly,FACS analysis showed that the proportion and the absolute number of F4/80+Mφcells obviously reduced (P<0.05);however,the proportion of γδT cells increased (P<0.05).Moreover,the proportion and the absolute number of CD4+T cells and CD8+T cells were significantly reduced (P<0.05). Finally, the proportion and the absolute number of CD62L+in CD4+T cells were upregulated vigorously,contrastly,the proportion and the absolute number of CD69+in CD4+T cells were notably up-regulated (P<0.05).Conclusion:miR-7 defeciency could significantly ameliorate the pathology of murine ALI,suggesting that it may play an important regulatory role in the development of ALI.

Objective:To detect the change of proportions of αβT lymphocytes in mesenteric lymph nodes of miR-7 knockdown (miR-7KD)mice,and preliminarily explore its importance.Methods: The volume,weight index and total cells number of mesenteric lymph node in miR-7KD mice were measured.The pathologic morphology change of mesenteric lymph nodes was observed by HE stai -ning.And the changes on proportion of αβT lymphocytes in mesenteric lymph nodes of miR-7KD mice were analyzed by Flow cytometry.Results:Compared with those of WT (wild type) mice,the volume,weight index,and the total cells number of mesenteric lymph node were significantly increased ( P<0.05 ).Moreover ,the pathologic morphology was significantly changed.The proportion and numbers of T lymphocyte were significantly increased;however,the proportion of B lymphocyte were significantly decreased (P<0.05). Notably,the proportion and number of CD4+T cells and CD8+T cells were significantly increased (P<0.05).Meanwhile,CD62L+T cell proportion were vigorously reduced and CD 69+T cell and IFN-γ+T cell proportion were notably up-regulated,which belong to CD4+and CD8+T cell(P<0.05).Conclusion:There was significant influence in the proportion of αβT lymphocytes in mesenteric lymph nodes of miR-7KD mice,suggesting that miR-7 might play an important role in the composition and function of lymphocytes in mesenteric lymph nodes.

Objective:To study the relationship between neutrophil to lymphocyte ratio (N/L) and traditional cardio‐vascular risk factors among community 35~64‐year‐old residents .Methods :A total of 1884 residents (548 males and 1336 females) from urban Shenyang city received baseline condition questionnaire on cardiovascular diseases and re‐lated diseases from Apr 2011 to Feb 2012. According to presence of cardiovascular risk factors or not ,subjects were divided into healthy control group (n=675) and risk factor group (n=1209);according to number of risk factors , risk factor group was further divided into one risk factor group (n=491) ,two risk factors group (n=263) and ≥3 risk factors group (n=455) .Morning blood sample and urine sample were retained to measure blood and urine rou‐tine ,blood glucose and blood lipid profile etc in all subjects .N/L was compared and analyzed among all groups .Re‐sults:Among patients with only one of following risk factors [hypertension ,diabetes mellitus (DM) ,dyslipidemia and obesity] ,N/L levels of patients with hypertension or DM were significantly higher than that of healthy control group [1.55(1.15 ,1.95) ,1.60(1.21 ,2.07) vs .1.45(1.09 ,1.91)] , P<0.05 both ,and there were no significant difference between any other one risk factor group and healthy control group , P>0.05 all .Among risk factor sub‐groups ,N/L level of ≥3 risk factors group was significantly higher than that of two risk factors group [1.57(1.16 , 2.04) vs .1.41(1.07 ,1.89) ,P<0.05] ,and there was no significant difference between any other two groups (P>0.05) .Conclusion:N/L significantly related to hypertension or DM ,and N/L level of ≥3 risk factors group was sig‐nificantly higher than that of two risk factors group ,N/L is helpful to assess risk of cardiovascular diseases .

Objective To compare the effect of novomix30 and metformin in treatment of diabetes mellitus combined with osteoporosis.Methods 117 patients diagnosed as type 2 diabetes mellitus (T2DM) combined with osteoporosis were collected from Sep.2013 to Apr.2017 in our hospital.They were divided into two groups:metformin group (n=53),and novomix group (n=64) according to different therapies.General information of the two groups were comparable.The patients of metformin group reveived calcium,alendronate and metformin.The patients of novomix group received calcium,alendronate and novomix.The lumbar bone mineral density (BMD),greater trochanter BMD,femoral neck BMD,Ward triangle BMD,the serum levels of BGP,alkaline phosphatase (ALP),β-cross-linked C-telopeptide of type Ⅰ collagen(β-CTX),1,25-(OH)2D3,the levels of fasting plasma glucose (FPG),2h plasma glucose (2h PG),HBA1c and adverse reactions were recorded during the treatment.Results The lumbar BMD,greater trochanter BMD,femoral neck BMD,Ward triangle BMD of novomix group were higher than those of metformin group after treatment (P＜0.05).The serum β-CTX levels of novomix group were lower than those of metformin group after treatment (P＜0.05),while the serum BGP,ALP,1,25-(OH)2D3 levels of novomix group were higher than those of metformin group after treatment (P＜0.05).The levels of FPG,2hPG,HBA1c had no significant difference between the two groups after treatment (P＞0.05).The adverse reactions rate of metformin group and novomix group was 28.30％ and 25.00％ respectively,and there was no significant difference between the two groups (P＞0.05).Conclusion Novomix30 can significantly improve bone metabolism level for patients combined with T2DM and osteoporosis,maintain bone remodeling balance,reduce bone loss,and improve BMD,which is worthy to be promoted.