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【Objective】In order to solve the problem that it is difficult to make the temperature sensor of the Photonic Crystal Fiber (PCF) with Surface Plasma Resonance (SPR), a D-structure PCF temperature sensor is proposed. The micro-structure and arrangement of the air hole are also designed. The method of coating the polishing surface of the optical fiber with gold layer is used to stimulate the SPR of the optical fiber.【Methods】Ethanol is used as a temperature-sensitive material, and the temperature-sensitive effect is used as the temperature sensing mechanism to achieve the effect of temperature sensing. The finite element analysis method is used to simulate the thickness of the gold layer and the size of the elliptical air hole of the fiber respectively. The coupling characteristics between the core mode and the surface plasma mode are analyzed under different conditions, and the structure of the sensor is optimized.【Results】The temperature characteristics of the sensor are simulated. In the range of -80~80 ℃, the sensitivity of the sensor is 3.4 nm /℃, and the linearity is better than 0.969 63.【Conclusion】The temperature sensor designed in this paper has a wide temperature detection range, satisfactory sensitivity, and linearity, which can be used for real-time temperature monitoring in industrial, agricultural, and medical fields.

As a biomedical material，TC4 titanium alloy is widely used in the field of bone tissue repair in clinical practice，with annual consumption of about one million pieces in China.However，the properties of TC4 titanium alloy as low wear resistance and poor biological activity seriously restricted its expansion in engineering application.Therefore，a micro-arc oxidation/hydrothermal coating on surface of TC4 was fabricated by utilizing the micro-arc oxidation/hydrothermal synthetic composite technology，and the effects of La(NO3)3 doping amount in the hydrothermal synthesis solution on the phase composition，micro morphology，microhardness，wear resistance and other parameters of the micro-arc oxidation/hydrothermal coating on TC4 titanium alloy were surveyed.Moreover，the micro-arc oxidation/hydrothermal coating on TC4 titanium alloy was characterized by XRD，SEM，microhardness tester and friction and wear testing machine.Results showed that the micro-arc oxidation/hydrothermal coating on TC4 titanium alloy was mainly composed of anatase TiO2 and hydroxyapatite.After hydrothermal treatment，La3+ in the synthetic solution entered the composite coating and participated in the coating reaction.With the increase of La(NO3)3 doping amount，the content of hydroxyapatite phase in the composite coating increased first and then decreased.When the doping amount of La(NO3)3 exceeded 24 mmol/L，the coating surface became smoother.In addition，the microhardness of micro-arc oxidation/hydrothermal composite coating on TC4 titanium alloy decreased first and then increased，and the friction coefficient increased first and then decreased.As the doping amount of La(NO3)3 reached 24 mmol/L，microhardness of the composite coating on TC4 titanium alloy acquired the minimum value，and it was about (271.8±3.1)HV9.8 N，the friction coefficient of the composite coating obtained the maximum value，and it was about 0.8～0.9.

Objective: To evaluate the biocompatibility of poiy lactic acid/bone matrix gelatin (PLA/BMG) composite biomaterial so as to lay a foundation for bone defect repair., Methods: Rats' MC3T3-E1 cells were cultured with leaching solution of PIJA/BMG and PLA material respectively for 7 days. The cell proliferation rate was tested by MTT and cell toxicity grading was carried out everyday. The PLA/BMG and MG3T3-E1 cells were co-cultured, the cell shape and proliferation were observed by inverted phase contrast microscope at 1, 3, and 5 days and cell adhesion by scanning electron microscope at 5 days. The PLA and PLA/BMG were implanted subcutaneously ilS Wistar rats. The histological observation was done, and the thickness of fibrous membrane, the number of inflammatory cells, and the vascularization area were measured at postoperative 2nd, 4th, and 8th week., Results: The tests for cytotoxicity in vitro showed that the cell proliferation rates were over 100% and the cell cytotoxic grades were grade 0 at 1-7 days in PLA/BMG group. While in PLA group, the cell proliferation rates were less than 100% and the cell cytotoxic grades were grade 1 at 2, 4, and 7 days. After co-culture of PLA/BMG and MC3T3-E1 cells, cells grew on the surface and in the pores of PLA! BMG, and the cellular morphology was triangle or polygon with abundant microvillus on the surface. After subcutaneous implantation, the rats survived to the end of experiment, and incision healed well. PLA was wrapped by connective tissue where there were a lot of lymphocytes and neutrophiic granulocytes. The cells and tissue grew slowly in PLA. The PLA! BMG materials were wrapped by utile connective tissue where there were a few inflammatory cells. The connective tissue growth was observed in the center of PLA/BMG. There was no significant difference in the thickness of fibrous membrane between 2 groups at each time point (P>0.05). The number of inflammatory cells of PLA/BMG group were significantly less than those in PLA group at 2, 4, and 8 weeks (P<0.05); the vascularization area was significantly larger than that in PLA group (P<0.05)., Conclusion: PLA/BMG composite biomaterials prepared by super critical-CO2 technique are good in cell and tissue biocompatibilty.

Objective: To review the recent progress of the small intestinal submucosa (SIS) in application research of tissue repair and reconstruction., Methods: The domestic and international articles on the SIS were reviewed and summarized., Results: As a natural extracellular matrix, SIS has outstanding biological advantages, such as good mechanical property, tissue compatibility, and lower immunogenicity. SIS has been used to repair and reconstruct various types of tissue defects in animal models and clinical application, especially in the treatment of hernia, urinary system disease, and refractory skin trauma. The development of the tissue engineering technology expands the field of SIS repair and reconstruction and promotes the intensive study of SIS. However, the long-term effect of SIS in tissue repair and reconstruction still remains to be further observation, while the cell/SIS material construction by tissue engineering technology also needs more studies., Conclusion: SIS has a widely promising application future in the tissue repair and reconstruction.

Objective: To evaluate the effect of tissue engineered skin with isogeneic cells on repairing skin defects in inbred rat model so as to provide relevant evidences for the clinical application., Methods: The skins of newborn inbred F344 rats were harvested and treated with Dispase trypsin to isolate the epidermal cells. The skins of adult Sprague Dawley rats were obtained and treated with hypertonic sodium-SDS-trypsin to prepare the acellular dermal matrix. The tissue engineered skin was reconstructed by submerging culturing and air-liquid interface culturing in vitro. The full-thickness skin defects of 1.5 cm x 1.5 cm in size were prepared along the dorsal both sides of 36 adult inbred F344 rats, and 72 defects were repaired with tissue engineered skin in experimental group (n=24), with allogeneic acellular dermal matrix in negative control group (n=24), and with autologous full-thickness skin in positive control group (n=24). Finally the gross observation, the survival rate, wound contraction rate, and histological observation were used to evaluate the effect., Results: The wound healed by first intension at 4 weeks postoperatively in the experimental group; the grafts connected with the adjacent tissue tightly and had normal appearance. At 4 weeks after operation, the survival rate of the graft was 0 in the negative control group; the survival rates were 62.5% (15/24) in the experimental group and 91.7% (22/24) in the positive control group, showing significant difference between 2 groups (chi2=5.779, P=0.016). The wound contraction rates of the experimental group and positive control group were significantly lower than that of the negative control group (P < 0.05), but no significant difference was found between the experimental group and positive control group (P > 0.05). Histological observation showed that slight inflammation reaction appeared at 1 week postoperatively in the experimental group; the regeneration of the blood vessel and the proliferation of the fibroblasts in dermis and the gradual maturation of epidermis were observed at 2 weeks, and new collagen deposition and collagen remodeling in the dermis of the graft were found at 4 weeks postoperatively., Conclusion: The tissue engineered skin is able to repair full-thickness skin defect of rats effectively, it has similar effect to the autologous full-thickness skin in preventing the wound contraction and promoting the wound healing, which provides experimental evidences for the clinical application.

Objective: To review the progress and clinical application of malleable bone paste/putty., Methods: Recent literature about malleable bone paste/putty was reviewed and analyzed., Results: The preparation and clinical application of malleable bone paste/putty have become increasingly mature. Many kinds of malleable bone paste/putty have been applied extensively and the good clinical results have been achieved in the treatment of the irregular bone defects. The materials and methods for preparing malleable bone paste/putty are different. Then they have different bone repair abilities., Conclusion: Malleable bone paste/putty provides effective method to treat irregular bone defects. But the malleable bone paste/putty still has some shortage, so further researches should be carried out.

Objective: To find out the recent progress in research of clinical application of fascia lata allograft., Methods: The domestic and international articles were reviewed to summarize the principal properties, processing techniques, and various uses of fascia lata allograft., Results: Histologically fascia lata is composed of parallel and compact bundles of collagen fibers with few cells and immunologically it is low-antigenic. After varied tissue processing and storage techniques, fascia lata, as the scaffold only with the extracellular matrix, has been used in clinical practice and achieved good results, such as ophthalmology, urology, and orthopaedics., Conclusion: Because of these unique properites in repairing defects and reconstructing functions, fascia lata allograft, as a natural biomaterial, is promising to be used in more aspects with the development of the biomedical techniques.

Objective: To investigate the effects of di-(2-ethylhexyl) phthalate (DEHP) exposure on pubertal development and reproductive endocrine function in prepubertal female rats and its possible mechanisms., Methods: 40 female SD rats at 3-week-old were randomly divided into a control group (corn oil) and three exposure groups, which were exposed consecutively for 28 days to DEHP by oral gavage at doses of 50, 150 and 500 mg/(kg x d). The onset of puberty was determined by daily examination for vaginal opening (OV), breast development and the first estrous cycle. By the end of the experiment, the rats were sacrificed during the diestrous stage. The gene expression interrelated with ovary function was detected by real-time PCR. Serum levels of follicle stimulating hormone (FSH) luteinizing hormone (LH), estradiol (E2), progesterone (P4) and testosterone (T) were measured by ELISA. The morphological change of ovaries was observed by HE staining under optical microscope. The expression of PPARgamma protein in ovary cells was measured by immuohistochemistry., Results: The age of vaginal opening was advanced by DEHP exposure in 500 mg/kg group, and the body weight was increased at the time of vaginal opening in 150 and 500 mg/kg groups (P < 0.05). Compared to the control group, the level of T in all DEHP groups was decreased; the levels of FSH and E2 were decreased and the level of P4 was increased in 150 and 500 mg/kg groups (P < 0.05). The gene expression of P4S0Aromin 150 and 500 mg/kg groups was significantly decreased compared to the control group. A significant increase of atretic follicles and a significant reduction of corpora lutea were observed in 150 and 500 mg/kg groups compared to the control group. The expression of PPARgamma protein in granulosa cells of follicle and corpora lutea in 150 and 500 mg/kg groups was higher than that in the control group and 50 mg/kg group (P < 0.05)., Conclusion: DEHP exposure can affect the pubertal development and reproductive endocrine function in prepubertal female rats, and its possible mechanism may be correlated with PPARgamma.

Objective: To evaluate the cytotoxicity of microdoses peracetic acid (PAA) so as to provide the evidence for making residual limit of PAA sterilization., Methods: Mouse fibroblasts (L929 cell line) cultured in vitro were observed to evaluate the influence of microdoses PAA including 1 x 10(-6), 2 x 10(-6), 3 x 10(-6), 4 x 10(-6), 5 x 10(-6), and 10 x 10(-6) (V/V). The proliferation of cells was determined by MTT assay at 2, 4, and 7 days of culture. The growth curve and the relative growth rate (RGR) were obtained. The cytotoxicity of PAA at different concentrations was evaluated according to RGR., Results: At 2, 4, and 7 days after culture, fibroblasts of 1 x 10(-6) group grew with normal morphology analogous to control group, while the cell growth of other groups were poor. With the increase of PAA concentration, the absorbance (A) values decreased, which suggested that there was a significant negative correlation between cell proliferation and PAA concentration. And the correlation coefficient was -1.000 at 2 and 4 days, - 0.964 at 7 days. There was no significant difference in A value between 1 x 10(-6) group and the control group (P > 0.05), while there were significant differences in A value between the control group and other concentration groups (P < 0.05). The growth curve of 1 x 10(-6) group was similar to that of the control group, both had obvious phase of exponential growth. The growth curves of other groups had no obvious phase of exponential growth. The cytotoxicity of 1 x 10(-6) group was classified as level 1, 2 x 10(-6) group as level 2, 3 x 10(-6) group as level 3, 4 x 10(-6) group as level 3-4, 5 x 10(-6) group and 10 x 10(-6) group as level 4., Conclusion: PAA of 1 x 10(-6) had no obvious cytotoxicity. The residual limit of PAA less than 1 x 10(-6) was recommended.

Objective: To explore the feasibility of using PKH26 as a cell tracer to construct tissue engineered bone., Methods: BMSCs isolated from the bone marrow of 1-week-old New Zealand white rabbit were cultured. The BMSCs at passage 3 were labeled with PKH26 and were observed under fluorescence microscope. The percentage of the labeled cells was detected by Flow cytometer. The labeled cells were induced to differentiate into osteoblasts in vitro and the morphology of the cells after induction was observed under inverted phase contrast microscope. The osteogenic induction was evaluated by ALP staining and Alizarin red staining. The cells labeled with PKH26 were seeded on the bio-derived bone to construct tissue engineered bone in vitro. Then the compound of cells and material were observed under fluorescence microscope. The compound of labeled cells and material were implanted into the rabbit thigh muscle, and the transformation of the labeled cells was observed by fluorescence microscope 14 and 28 days later., Results: Fluorescence microscope observation: the BMSCs labeled by PKH26 were spherical and presented with red and uniform-distributed fluorescence, and the contour of the cells were clearly observed when they were adherent 24 hours after culture. Flow cytometric detection revealed that the percentage of labeled cells was 97.2%. After osteogenic induction, the morphology of the cells changed from long-fusiform to polygon-shape or cube-shape, more ECM was secreted, and the ALP and the Alizarin red staining were positive. At 48 hours after culturing the PKH26 labeled BMSCs with bio-derived bone, the fluorescence microscope observation showed that there was red fluorescence on the surface and inside of the material. At 14 days after implantation, the labeled cells with red and light fluorescence were evident in the implantation area; while at 28 days, the cells with red fluorescence were still evident but less in quantity and weaker in fluorescence strength., Conclusion: PKH26 can be used as BMSCs label for the construction of tissue engineered bone in vitro and the short-term tracing in vivo.

Objective: To explore the interventional effect of platelet lysate (PL) on osteogenic differentiation of BMSCs by induction in rats in vitro., Methods: Twenty-four clean-grade adult Wistar rats, weighing from 250 g to 300 g, male or female, were included in this study. PL was obtained through three times of centrifugation and repeated freeze-thaw for the blood aspirated from cardiac cavities in 16 Wistar rats. ELISA assay was conducted to detect the concentration of growth factors PDGF, TGF-beta1, IGF-1 and VEGF in PL. The BMSCs harvested by flushing femurs of 8 adult Wistar rats were isolated, cultivated and expanded in vitro. The cells at the 4 passage were performed for osteogenic differentiation by induction in three groups of A (5% PL of final concentration in basic induction medium), B (1% PL of final concentration in basic induction medium), and C (no presence of PL in basic induction medium as a control). The morphological changes of the cells were dynamically observed with inverted phase contrast microscope during the whole period. At different time-points, ALP staining (7 days) and ALP/TP (2, 8, 12 days) of the cells were detected to evaluate ALP activity, and the mineral formation in extracellular matrix was examined with Alizarin red staining which provided quantitative analysis of mineral deposits., Results: ELISA assay showed that the content of PDGF, TGF-beta1, IGF-1 and VEGF in PL reached (300 +/- 30), (140 +/- 25), (80 +/- 35), (70 +/- 20) pg/mL, respectively. Morphological observation displayed BMSCs in group A or B gradually turned from spindle-shape to square- or polygon-shape as the morphological type of osteoblast-like cells at 7 days. The cells in group A showed slower shape changes but higher proliferation than that in group B or C. Moreover, at the 20 days, the cells in group A still displayed dense growth and produced obviously decreased amount of mineral deposits in ECM when compared with group B or C. At the 7 days, the cells of group A showed smaller amount of granules positive for ALP staining in cytoplasm when compared with groups B and C, and displayed marked reduction in ALP activity assay at the 2, 8, and 10 days compared with that of groups B and C (P < 0.05). At the 20 days, Alizarin red staining showed the number of mineral deposits in groups A, B and C were 7.67 +/- 1.10, 12.87 +/- 0.81 and 15.59 +/- 0.25, respectively, while the area of mineral deposits were (161 778.70 +/- 44 550.80), (337 349.70 +/- 56 083.24), and (415 921.70 +/- 71 725.39) pixels, respectively. The number of mineral deposits and the area of mineral deposits in group A were smaller than those in groups B and C (P < 0.05). But there was no statistically significant difference between groups B and C (P > 0.05)., Conclusion: PL is a kind of system carrying various growth factors. Exposure of PL inhibits both ALP activity and mineral formation of BMCs in a dose-dependent way under the osteogenic induction environment.

Objective: To understand the pathogenic effect and the correlation between the genotype and phenotype of the 4 novel missense mutations (G247S, E280G, P362T and A434D) of phenylalanine hydroxylase gene (PAH)., Methods: (1) The enzyme activity of the 4 mutants was assessed by using transient protein expression in mammalian cells. (2) The PAH amino acid sequences among different animal species were alignmented. (3) The effects of the 4 missense mutations on the protein structure were analyzed. (4) The clinical phenotype of the patients with PKU were analyzed, according to their blood Phe levels prior to treatment and the Phe tolerance., Results: (1) The residual enzyme activity expressed in vitro of G247S, E280G, P362T and A434D were 3.1%, 0.4%, 8.2% and 21.7% of the wild-type PAH respectively; (2)Gly247, Glu280 and Pro362 were among the highly conserved amino acids, while Ala434 was only moderately conserved; (3) As revealed by 3D structural analysis, G247S and E280G, being located at the active center of the enzyme, interfered with the binding of PAH to BH4 and ferrousion respectively, while P362T and A434D affected the formation and stability of the dimer and the tetramer of PAH; (4) As shown by clinical phenotypic analysis, classical PKU were observed in patients carrying G247S and E280G, moderate PKU were observed in patients carrying A434D, whereas both classical and moderate PKU were observed in patients carrying P362T., Conclusion: (1) The E280G, G247S, P362T and A434D are all disease-causing mutations, with those located at the center of the enzyme displaying the most marked pathogenic effect; (2)The results of the structural analysis of the 3D molecule are consistent with the activity assessment of the enzyme expressed in vitro; (3) The consistency is observed between the genotype, the enzymatic activity expressed in vitro and the clinical phenotype.

Objective: To fabricate a novel porous bioactive composite biomaterial consisting of poly lactic acid (PLA)-bone matrix gelatin (BMG) by using the supercritical carbon dioxide fluid technique (SC-CO2) and to evaluate its osteoinductive activity., Methods: The cortical bones selected from healthy adult donors were processed into BMG by the defatting, demineralizing, and deproteinizing processes. PLA and BMG were mixed at a volume radio of 3 : 1; then, the PLA-BMG mixed material and the pure PLA material were respectively placed in the supercritical carbon dioxide reaction kettles, and were respectively added by the NaCl particles 100-200 microm in diameter for the porosity of the materials so that the porous PLA-BMG composite material and the porous PLA composite material could be formed. The mouse osteoblast-like MC3T3-E1 cells were cultured in the dulbecco's modified eagle medium (DMEM) supplemented with 10% fetal bovine serum. Then, 20 microl of the MC3T3-E1 cell suspensions containing 2 X 10(6) cells /ml were delivered into the culturing plate (24 wells/plate) made of the different materials, which were co-cultured for 2 weeks. In the PLA-BMG group, 100 microg of the crushed PLA-BMG material was contained in each well; in the PLA group, 100 microg of the crushed PLA material was contained in each well; and in the DMEM group, only DMEM was contained, which served as the control group. There were 6 wells in each group. The quantitative analysis on the calcification area was performed by the staining of the alizarin red S. The co-cultured cells were harvested and lysated in 1 ml of 0. 2% Nonidet P-40 by the ultrasonic lysating technique. Then, the ALP activity and the Ca content were measured according to the illuminations of the reagent kits., Results: The porous PLA-BMG composite material showed a good homological porosity with a pore diameter of 50-150 microm and a good connectivity between the pores. The ALP activity, the Ca content, and the calcification area were significantly greater in the PLA-BMG group than in the PLA group and the control group (325.59 +/- 70.40 U/gprot, 3.51+/- 1.64 mmol/gprot, 42.98 +/- 4.44% vs. 63. 62 +/- 30.01 U/gprot, 1.04+/-0.21 mmol/gprot, 9.55+/-1.94%, and 2.40+/-1.47 U/gprot, 0.70+/-0.24 mmol/gprot, 0.86+/-0.41%; P<0.05). Meanwhile, there was a statistically significant difference between the PLA group and the control group in the ALP activity and the calcification area (P< 0.05)., Conclusion: The porous PLA-BMG composite material prepared by the use of SC-CO2 has a good osteoinductive activity and can be used as a promising bone biomaterial and a bone tissue engineered scaffold.

Objective: To review the development and quality control of modern tissue banks., Methods: The rules, regulations and the management literatures about tissue banks were extensively and comprehensively reviewed., Results: Tissue banks have a significant progress and are developing to concentration, industrialization and standardization gradually. Quality control is being paid more attention in modern tissue banks., Conclusion: Modern tissue banks will have a good future and the quality control must be intensified.

Objective: To review the recent research and clinical progress of artificial osteoconductive materials., Methods: Recent and related literatures were extensively and comprehensively reviewed., Results: Many achievements about the clinical application of the artificial osteoconductive materials were made. It had become one of the hotspots of bone tissue engineering research. Some were clinically applied and good clinical results were achieved., Conclusion: As it provides new clinic method for treating bone defect, artificial osteoconductive material is of great potential in its application. To improve its microstructure, macro-shape, mechanism of osteoinductive ability, and to accelerate new bone formation will be the hotspots of the research on artificial osteoconductive material.

To examine the effects of carbofuran on the testis of male rats. The activities of beta-glucuronidase (beta-G), glucose-6-phosphate dehydrogenase(G-6-PD) and lactate dehydrogenase isoenzyme-x (LDHx) in serum and testis homogenate were determined for the rats given carbofuran at the dises of 0.3, 1.5 and 3.0 mg/kg orally for 7, 35 and 77 days. The results showed that after 7 days, the activities of beta-G in serum in all exposed groups were lower than those in control (P < 0.05). The activities of beta-G in testis homogenate in 0.3 mg/kg and 3.0 mg/kg were higher or lower than those in control (P < 0.05), respectively. After 77 days, the activities of G-6-PD in serum both in 1.5 mg/kg and 3.0 mg/kg were lower than those in control (P < 0.05). The activities of LDHx in testis homogenate in 3.0 mg/kg were lower than those in control (P < 0.05). It suggested that exposure to carbofuran could testis damage.