FRAGILE CULM 18 encodes a UDP-glucuronic acid decarboxylase required for xylan biosynthesis and plant growth in rice.

Although UDP-glucuronic acid decarboxylases (UXSs) have been well studied with regard to catalysing the conversion of UDP-glucuronic acid into UDP-xylose, their biological roles in grasses remain largely unknown. The rice (Oryza sativa) genome contains six UXSs, but none of them has been genetically characterized. Here, we reported on the characterization of a novel rice fragile culm mutant, fc18, which exhibited brittleness with altered cell wall and pleiotropic defects in growth. Map-based cloning and transgenic analyses revealed that the FC18 gene encodes a cytosol-localized OsUXS3 and is widely expressed with higher expression in xylan-rich tissues. Monosaccharide analysis showed that the xylose level was decreased in fc18, and cell wall fraction determinations confirmed that the xylan content in fc18 was lower, suggesting that UDP-xylose from FC18 participates in xylan biosynthesis. Moreover, the fc18 mutant displayed defective cellulose properties, which led to an enhancement in biomass saccharification. Furthermore, expression of genes involved in sugar metabolism and phytohormone signal transduction was largely altered in fc18. Consistent with this, the fc18 mutant exhibited significantly reduced free auxin (indole-3-acetic acid) content and lower expression levels of PIN family genes compared with wild type. Our work reveals the physiological roles of FC18/UXS3 in xylan biosynthesis, cellulose deposition, and plant growth in rice.

Enhanced Adhesion of Carbon Nanotubes by Dopamine Modification.

According to the fact that gecko-inspired vertically aligned carbon nanotubes (VA-CNTs) exhibit ultrastrong adhesion, dopamine is utilized to make a modification to this traditional biomimetic material. The composite material is tested for adhesion performance under different environmental conditions by an atomic force microscope. The adhesion force of the modified VA-CNTs does not show obvious fluctuation during the gradual heating process; however, the material gains improved adhesion when increasing the ambient humidity. In addition, the modified CNTs show a stronger adhesion force than the original CNTs in their performance tests. The dopamine polymer has a good combination with CNTs, which is responsible for the aforementioned excellent performance. Overall, this modification method is simple, convenient, efficient, and environmentally friendly, which all indicates a promising future in its application. The modified CNTs are expected to be used for super-adhesion in harsh environments, as well as in the field of microelectronics.

Functional outcome of en bloc excision and custom prosthetic replacement for giant cell tumor of the distal radius.

BACKGROUND: Giant cell tumors (GCT) of the distal radius at Campanacci grade II/III are particularly challenging to treat. Wide excision is the management of choice, but this creates a defect at the distal end of radius. We treated 11 cases of GCT of the distal radius by en bloc excision and custom prosthetic replacement. The purpose of this study was to present our experience and assess the functional outcomes of all patients treated with this surgery. MATERIALS AND METHODS: Between 2005 and 2014, we followed up 11 patients with GCT of the distal radius who were treated with en bloc excision and custom prosthetic replacement. All cases were evaluated based on clinical and radiological examinations, passive range of motion (ROM) of the wrist joint, complications, and Musculoskeletal Tumor Society (MSTS) score. RESULTS: Mean follow-up period was 55.5 months (24-83 months); mean resected length of the radius was 7.9 cm. One patient had tumor recurrence in the soft tissues after 15 months (recurrence rate 9.09 %). No patient had fracture, recurrence in the bone, metastases, or immune rejection. No complications were seen, such as loosening, rupture, or dislocation of the custom prosthesis. One patient developed superficial infection at the operative site which resolved after a course of antibiotics for 4 weeks. One patient experienced pain, which could be endured without the need for analgesics. Average ROM was 40.9° of dorsiflexion, 30.0° of volar flexion, 46.4° of supination, and 38.2° of pronation. Mean grip strength was 71 % (42-86 %). Overall revised MSTS score averaged 80.3 % (63.3-93.3 %) with one being excellent, five good, and five satisfactory. CONCLUSION: En bloc excision and custom prosthetic replacement for a Campanacci grade II/III GCT of the distal radius results in reasonable functional outcome at intermediate follow-up evaluation. Although average ROM of the ipsilateral wrist is poorer than some studies with other techniques, this method can be considered a reasonable option.

Dynamic adhesion forces between microparticles and substrates in water.

The interactions between micrometer-sized particles and substrates in aqueous environment are fundamental to numerous natural phenomena and industrial processes. Here we report a dynamically induced enhancement in adhesion interactions between microparticles and substrates immerged in water, air, and hexane. The dynamic adhesion force was measured by pulling microsized spheres off various substrate (hydrophilic/hydrophobic) surfaces at different retracting velocities. It was observed that when the pull-off velocity varies from 0.02 to 1500 µm/s, there is 100-200% increase in adhesion force in water while it has a 100% increase in nitrogen and hexane. The dynamic adhesion enhancement reduces with increasing effective contact angle defined by the average cosine of wetting angles of the substrates and the particles, and approaches the values measured in dry nitrogen and hexane as the effective contact angle is larger than 90(o). A dynamic model was developed to predict the adhesion forces resulting from this dynamic effect, and the predictions correlate well with the experimental results. The stronger dynamic adhesion enhancement in water is mainly attributed to electrical double layers and the restructuring of water in the contact area between particles and substrates.

Identification of symptom clusters in patients with ankylosing spondylitis.

Symptom cluster refers to a group of 3 or more related symptoms that occur together. Our objectives were to: (1) investigate the frequency, severity and gender difference of symptoms in patients with ankylosing spondylitis (AS); and (2) identify symptom clusters in AS patients. A cross-sectional questionnaire-based survey was conducted using the Patient Health Questionnaire Symptoms Group combined with self-designed variables. Demographic and symptom variables between male and female patients in terms of C-reactive protein (CRP) and human leukocyte antigen (HLA)-B27 status were analyzed with 2-tailed independent t test for continuous variables and Chi-square or Fisher's exact test for categorical variables. Symptom clusters were extracted and analyzed by principal component analysis. There were 122 AS patients included in the study. The most severe symptoms included severe back pain, extremity or joint pain, difficulty in breathing, constipation, intestine discomfort and diarrhea. Stomachache was more prevalent in male patients in which odds ratio was 4.60 (CI 1.59-12.97) (P = .006). Patients with HLA-B27 negativity or a higher CRP value were more likely to have dry mouth. Four symptom clusters were classified, which explained 58.4% of the total variation. They were named as the gastrointestinal-cardiac cluster, the fatigue-sleep disturbance cluster, the headache-chest pain cluster, and the mouth-eye cluster. The symptoms appeared to cluster into 4 groups in AS patients, which should be noticed in clinical care.

Tea Polyphenol Liposomes Overcome Gastric Mucus to Treat Helicobacter Pylori Infection and Enhance the Intestinal Microenvironment.

Infection with Helicobacter pylori (Hp) is one of the leading causes of stomach cancer. The ability to treat Hp infection is hampered by a lack of stomach gastric acid environment. This work introduces a nanoliposome that can rapidly adjust the gastric acid environment to ensure a drug's optimal efficacy. We introduce CaCO3@Fe-TP@EggPC nanoliposomes (CTE NLs) that are composed of Fe3+ and tea polyphenols (TPs) forming complexes on the surface of internal CaCO3 and then with lecithin producing a phospholipid bilayer on the polyphenols' outer surface. Through the action of iron-TP chelate, the phospholipid layer can fuse with the bacterial membrane to eliminate Hp. Furthermore, CaCO3 can promptly consume the excessive gastric acid, ensuring an ideal operating environment for the chelate. TPs, on the other hand, can improve the inflammation and gut microbes in the body. The experimental results show that CTE NLs can quickly consume protons in the stomach and reduce the bacterial burden by 1.2 orders of magnitude while reducing the inflammatory factors in the body. The biosafety evaluation revealed that nanoliposomes have good biocompatibility and provide a new strategy for treating Hp infection.

Machine learning guided microwave-assisted quantum dot synthesis and an indication of residual H2O2 in human teeth.

The current preparation methods of carbon quantum dots (CDs) involve many reaction parameters, which leads to many possibilities in the synthesis processes and high uncertainty of the resultant production performance. Recently, machine learning (ML) methods have shown great potential in correlating the selected features in many applications, which can help understand the relevant structure-function relationships of CDs and discover better synthesis recipes as well. In this work, we employ the ML approach to guide the blue CD synthesis in microwave systems. After optimizing the synthesis parameters and conditions, the quantum yield (QY) increases to about 200% higher than the average value of the prepared samples without ML guidance. The obtained CDs are applied as fluorescent probes to monitor hydrogen peroxide (H2O2) in human teeth. The CD probe exhibits a linear relationship with the concentration of H2O2 ranging from 0 to 1.1 M with a lower detection limit of 0.12 M, which can effectively detect the residual H2O2 after bleaching teeth. This work shows that the adopted ML methods have considerable advantages in guiding the synthesis of high-quality CDs, which could accelerate the development of other novel functional materials in energy, biomedical, and environmental remediation applications.

A New Feasible Technique for Polytetrafluoroethylene Suture Buttress-Reinforced Pancreaticojejunostomy (PBRP): Mechanical Analysis and a Prospective, Randomized Controlled Trial.

OBJECTIVES: Postoperative pancreatic fistula (POPF) is a major concern after pancreatoduodenectomy (PD). We recently designed a new anastomotic method to reduce the rate of pancreatic fistula: polytetrafluoroethylene suture buttress-reinforced pancreaticojejunostomy (PBRP). METHODS: An animal model and a computer simulation were used to measure the maximum stress and tensile strength of the pancreas with and without the suture buttresses. Then, a randomized controlled trial (RCT) was performed to compare the outcome of PD between patients who underwent PBRP vs traditional pancreaticojejunostomy (TP). RESULTS: The maximum load in the animal model was significantly higher with the suture buttresses than without (5.47 ± 1.67 N vs 3.72 ± 1.36 N, p < 0.01), and in the computer simulation, the peak stress was lower with the suture buttresses than without (54.86 vs 486.8 MPa). There were no significant differences between the two groups in the overall frequency of POPF, but the rate of clinically relevant POPF was significantly lower in the PBRP group (2.8 vs 22.8%, p = 0.028). The pancreaticojejunostomy time was significantly longer in the PBRP group (19.57 ± 3.31 vs 17.17 ± 4.83 min, p = 0.018), and the PBRP group showed a shorter drainage tube retention duration (10 vs 12 days, p = 0.006) and postoperative hospital stay (13 d vs 15 d, p = 0.031). CONCLUSIONS: PBRP is a feasible and reliable procedure for preventing clinically relevant POPF. Additional multi-institution randomized trials should be conducted to confirm these results.

MVsCarta: A protein database of matrix vesicles to aid understanding of biomineralization.

Matrix vesicles (MVs) are membranous nanovesicles released by chondrocytes, osteoblasts, and odontoblasts. They play a critical role in modulating mineralization. Here, we present a manually curated database of MV proteins, namely MVsCara to provide comprehensive information on MVs of protein components. In the current version, the database contains 2,713 proteins of six organisms identified in bone, cartilage, tooth tissues, and cells capable of producing a mineralized bone matrix. The MVsCarta database is now freely assessed at http://bioinf.xmu.edu.cn/MVsCarta. The search and browse methods were developed for better retrieval of data. In addition, bioinformatic tools like Gene Ontology (GO) analysis, network visualization and protein-protein interaction analysis were implemented for a functional understanding of MVs components. Similar database hasn't been reported yet. We believe that this free web-based database might serve as a useful repository to elucidate the novel function and regulation of MVs during mineralization, and to stimulate the advancement of MV studies.

Systemic BMSC homing in the regeneration of pulp-like tissue and the enhancing effect of stromal cell-derived factor-1 on BMSC homing.

Pulp regeneration caused by endogenous cells homing has become the new research spot in endodontics. However, the source of functional cells that are involved in and contributed to the reconstituting process has not been identified. In this study, the possible role of systemical BMSC in pulp regeneration and the effect of stromal cell-derived factor-1 (SDF-1) on stem cell recruitment and angiogenesis were evaluated. 54 mice were divided into three groups: SDF-1 group (subcutaneous pockets containing roots with SDF-1 absorbed neutralized collagen gel and the green fluorescent protein (GFP) positive BMSCs transplantation via the tail vein), SDF-1-free group (pockets containing roots with gel alone and GFP + BMSCs transplantation) and Control group (pockets containing roots with gel alone). The animals were sacrificed after the roots were implanted into subcutaneous pockets for 3 weeks. Histomorphometric analysis was performed to evaluate the regenerated tissue in the canal by hematoxylin and eosin (HE) staining. The homing of the transplanted BMSCs was monitored with a fluorescence microscope and immunohistochemical analysis. The expression of ALP in new formed tissue was detected immunohistochemically. Dental-pulp-like tissue and new vessels were regenerated and GFP-positive BMSCs and expression of ALP could be observed in both SDF-1 group and SDF-1-free group. Furthermore, more GFP+ cells, stronger expression of ALP and stronger angiogenesis were found in the SDF-1 group than in the SDF-1-free group. To conclude, systemic BMSC can home to the root canal and participate in dental-pulp-like tissue regeneration. Intracanal application of SDF-1 may enhance BMSC homing efficiency and angiogenesis.

Systemically transplanted human gingiva-derived mesenchymal stem cells contributing to bone tissue regeneration.

As novel postnatal stem cells, gingiva-derived mesenchymal stem cells (GMSCs) have been considered as an ideal candidate cell resource for tissue engineering and cell-based therapies. GMSCs implanted into sites of injury have been confirmed to promote the injury repair. However, no studies have demonstrated whether systemically transplanted GMSCs can home to the bone injuries and contribute to the new bone formation in vivo. In this study, we transplanted human GMSCs into C57BL/6J mice with defects in mandibular bone via the tail vein to explore the capacity of transplanted GMSCs to promote bone regeneration. Results showed that the transplanted GMSCs were detected in the bone defects and employed in new bone formation. And the newly formed bone area in mice with GMSCs transplantation was significantly higher than that in control mice. Our findings indicate that systemically transplanted GMSCs can not only home to the mandibular defect but also promote bone regeneration.

Effect of umbilical cord mesenchymal stem cell in peri-implant bone defect after immediate implant: an experiment study in beagle dogs.

BACKGROUND: For the sake of reducing post extraction resorption, getting optimal positioning of the implant and shortening treatment time, immediate implant placement following tooth extraction has been proposed as a treatment option. However, the large bone defect peri-implant has a negative influence on the process of bone healing. In this study, umbilical cord mesenchymal stem cells (UCMSCs) were transplanted into the bone defect peri-implant inbeagle dogs and the effect of UCMSCs on bone regeneration in peri-implant were assessed. METHODS: The mandibular second, third and fourth premolars of 8 beagle dogs were extracted bilaterally. The defects in one side were filled with platelet-rich fibrin (PRF) and then UCMSCs were injected into the defect area, while the defects in the other side were filled with PRF only as control group. The titanium implant was placed into the distal root socket of each extracted tooth. The animals were sacrificed at week 2, 4 and 8 post operative. The bone defects adjacent to the implant which are 4 mm in height, 4 mm in the mesio-distal direction and 3.5 mm in the bucco-lingual direction were made after immediate implant. Histomorphometric analysis was performed using methylene blue-fuchsin acid staining and hematoxylin and eosin (HE) staining to evaluate bone regeneration. RESULTS: The direct bone-to-implant contact (BIC) in the experiment after 4 and 8 weeks was 56.47±1.18% and 76.23±2.08%; and in the control group was40.79±0.65% and 61.17±2.79%, respectively. The percentage of newly formed bone after 2, 4 and 8 weeks was 17.60±1.5%, 49.82±4.02% and 67.16±2.1% in experiment group; and in control group 14.30±1.25%, 37.04±2.29% and 58.83±3.36%, respectively. These results represented significant differences statistically. CONCLUSION: Intra-bone marrow injection of UCMSCs can promote new bone formation. UCMSCs can be used to as excellent seed cells to repair the large defect peri-implant after immediate implant.

Effect of umbilical cord mesenchymal stem cell in peri-implant bone defect after immediate implant: an experiment study in beagle dogs.

BACKGROUND: For the sake of reducing post extraction resorption, getting optimal positioning of the implant and shortening treatment time, immediate implant placement following tooth extraction has been proposed as a treatment option. However, the large bone defect peri-implant has a negative influence on the process of bone healing. In this study, umbilical cord mesenchymal stem cells (UCMSCs) were transplanted into the bone defect peri-implant in beagle dogs and the effect of UCMSCs on bone regeneration in peri-implant were assessed. METHODS: The mandibular second, third and fourth premolars of 8 beagle dogs were extracted bilaterally. The defects in one side were filled with platelet-rich fibrin (PRF) and then UCMSCs were injected into the defect area, while the defects in the other side were filled with PRF only as control group. The titanium implant was placed into the distal root socket of each extracted tooth. The animals were sacrificed at week 2, 4 and 8 post operation. The bone defects adjacent to the implant which are 4 mm in height, 4 mm in the mesio-distal direction and 3.5 mm in the bucco-lingual direction were made after immediate implant. Histomorphometric analysis was performed using methylene blue-fuchsin acid staining and hematoxylin and eosin (HE) staining to evaluate bone regeneration. RESULTS: The direct bone-to-implant contact (BIC) in the experiment after 4 and 8 weeks was 56.47 ± 1.18% and 76.23 ± 2.08%; and in the control group was40.79 ± 0.65% and 61.17 ± 2.79%, respectively. The percentage of newly formed bone after 2, 4 and 8 weeks was 17.60 ± 1.5%, 49.82 ± 4.02% and 67.16 ± 2.1% in experiment group; and in control group 14.30 ± 1.25%, 37.04 ± 2.29% and 58.83 ± 3.36%, respectively. These results represented significant differences statistically. CONCLUSION: Intra-bone marrow injection of UCMSCs can promote new bone formation. UCMSCs can be used to as excellent seed cells to repair the large defect peri-implant after immediate implant.

Hyperlipidemia compromises homing efficiency of systemically transplanted BMSCs and inhibits bone regeneration.

PURPOSE: Mesenchymal stem cells (MSCs) can selectively home to bone defects and play an essential role in promoting bone regeneration. As an adverse effect factor for bone metabolism, hyperlipidemia significantly impairs bone regeneration. In this study, bone marrow stromal cells (BMSCs) were systemically transplanted into a hyperlipidemic mouse model to explore the effect of hyperlipidemia on stem cell recruitment and bone regeneration. METHODS: Hyperlipidemia was established in ApoE-/- mice (on C57BL/6J background) fed with a high fat diet (HFD) for five weeks. C57BL/6 mice fed with the same diet served as controls. BMSCs labeled with the green fluorescent protein (GFP) were then injected via the tail vein and bone defects were created in the mandibles. The animals were sacrificed at weeks 1, 2 and 4 after surgery, and the fate of the transplanted BMSCs was monitored with a fluorescence microscope and immunohistochemical analysis. After hematoxylin and eosin (HE) staining and Masson's Trichrome (MT) staining, histomorphometric analysis was performed to evaluate bone regeneration. RESULTS: In both groups transplanted with BMSCs, the number of GFP-positive BMSCs detected in the bone defects reached its peak at 1 week after surgery and was decreased thereafter. However, at all time points, less GFP+ cells were detected in the ApoE-/- mice than in the corresponding control mice. BMSCs transplantation significantly enhanced new bone formation, but to a lesser degree in the ApoE-/- mice when compared with the control mice. CONCLUSIONS: Hyperlipidemia compromises homing efficiency of systemically transplanted BMSCs and inhibits bone regeneration.

[Detection of anaerobes and drug sensitivity from the periodontal pockets of patients with combined periodontal-endodontic lesions].

PURPOSE: To investigate the correlation between the composition of bacterial flora isolated from deep periodontal pockets with combined periodontal-endodontic lesions, and to test the antibiotic susceptibility of anaerobes. METHODS: Microbial samples were taken from 82 deep periodontal pockets with combined periodontal-endodontic lesions using adequate techniques, and divided into two groups: endo-perio group and perio-endo group. Antibiotic susceptibility of cultivable anaerobes were tested with agar dilution method. RESULTS: Eighty-six cultivable anaerobes were isolated, including Streptococcus spp, Prevotella spp, Actinomycetes spp, Veillonella spp, Fusobacterium spp and etc. 53.4% were gram-positive anaerobes, while 46.51% were gram-negative anaerobes. The detection rate of anaerobes in endo-perio group and that in perio-endo group had significant difference. Most isolated anaerobes were sensitive to six drugs. The resistance rates of penicillin, clindamycin, metronidazole were 6.8%, 13.9% and 2.2%. CONCLUSIONS: There is a close relationship between anaerobes and combined periodontal-endodontic lesions. Drug sensitive susceptibility should be detected prior to clinical treatment of combined periodontal-endodontic lesions.

[Clinical effect of pit and fissure sealant used in combination with different etching adhesive and 3M-Z350 flowable resin on young permanent teeth].

PURPOSE: To compare the effect of different etching adhesive and flowable resin in deep pits and fissures of young permanent molars sealant technique. METHODS: Children aged 6-8 years old were included in the study. The split mouth design was used. The first permanent molars were randomly assigned into 2 experimental groups:A and B.The teeth in group A were sealed with flowable resin and self-etching adhesive,while the teeth in group B were sealed with flowable resin and phosphate acid system. The children were followed up every year, and the sealants were observed and evaluated. SPSS13.0 software package was used for statistical analysis. RESULTS: After 1 year, 2 and 3 years,the retention rate of group A was significantly lower than that of group B(P<0.05),while group A had more caries than group B(P<0.05) except at 1-year. CONCLUSION: Self-etching adhesive and flowable resin doesn't have excellent clinical effect on caries prevention.

[Cytocompatibility of chitosan-based thermosensitive hydrogel to human periodontal ligament cell].

PURPOSE: The aim of this investigation was to evaluate the cytocompatibility of an in situ chitosan-quaternized chitosan/α, ß-glycerophosphate (CS-HTCC/GP) thermosensitive hydrogel in vitro. METHODS: The primary cells were isolated from human periodontal ligament and cultured. The role of different concentrations of CS-HTCC/GP extract to HPDLCs was evaluated by MTT assay and alkaline phosphatase (ALP) activity. Also, the ultra-architecture of HPDLCs was determined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) respectively. SPSS13.0 software package was used for statistical analysis. RESULTS: By immunocytochemical method, the cells were stained positively to antibodies against vimentin, and negatively to antibodies against cytokeratin, which indicated that they were external embryo mesenchymal cell without epithelial cell mixure. CS-HTCC/GP thermosensitive hydrogel promoted proliferation of HPDLCs,especially at 3d and 5d, the results was significantly different (P<0.001). ALP activity was significantly greater in group 2 and 3 than in group 4 after 5d (P<0.001). Also, no negative influence to ultrastructure of HPDLCs was found through SEM and TEM. CONCLUSIONS: The results indicate that CS-HTCC/GP thermosensitive hydrogel exhibits excellent cytocompatibility and has potential to be used as an in situ injectable local periodontal drug delivery vehicle and a tissue-engineering scaffold for periodontal disease therapy.

[A preliminary analysis of the ratio between the upper and lower anterior teeth].

PURPOSE: The widths of anterior teeth are measured and compared to see if there was any specific ratio between the anterior teeth, and to provide some referential data for clinical application in esthetic dentistry. METHODS: Gypsum casts of the maxillary and mandibular arches were made by traditional ways. With the help of dividers and vernier calipers, the widths of anterior teeth were measured. The mean values were gained by doing the measurement several times. SAS6.12 software package was used for grouped t test, paired t test and REG regression. RESULTS: Statistically significant difference(P<0.01) was observed, when comparing the widths of anterior teeth with their ideal golden section(0.618 or 1.618). There were statistically significant differences in the correlation coefficient of anterior teeth(P=0.0001). CONCLUSIONS: The golden section is not found in the anterior teeth. There is some proportional relationships between the upper and lower anterior teeth.

[An in vitro evaluation of the antibacterial activity of chitosan-based thermosensitive hydrogel against periodontal pathogens].

PURPOSE: To evaluate the in vitro antibacterial activity of chitosan - quaternized chitosan/alpha, beta-glycerophosphate (CS-HTCC/GP) thermosensitive hydrogel against three periodontal pathogens- P. gingivalis, P. intermedia, and A. actinomycetemcomitans. METHODS: An agar diffusion method was used to assess the antimicrobial property of CS-HTCC/GP thermosensitive hydrogel with minimum inhibitory concentration (MIC) and inhibitory zone measurement. SPSS13.0 software package was used for Student's t test. RESULTS: Three periodontal pathogens strains were all susceptible to CS-HTCC/GP thermosensitive hydrogel. Both matrix of thermosensitive hydrogel and antibiotic exhibited stronger antibacterial activity especially when they were combined. CONCLUSIONS: CS-HTCC/GP thermosensitive hydrogel is not only as the vehicle of antibiotics which joins the local drug delivery system but as an activator which takes part in the antibacterial process.

A novel hydrogen peroxide sensor based on the direct electron transfer of horseradish peroxidase immobilized on silica-hydroxyapatite hybrid film.

The direct electron transfer of immobilized horseradish peroxidase (HRP) on silica-hydroxyapatite (HAp) hybrid film-modified glassy carbon electrode (GCE) and its application as H(2)O(2) biosensors were investigated. On silica/HRP-HAp/GCE, HRP displayed a fast electron transfer process accompanied with one proton participate in. This sensor exhibited an excellent electrocatalytic response to the reduction of H(2)O(2) without the aid of an electron mediator. The proposed biosensor showed good reproducibility and high sensitivity to H(2)O(2) with the detection limit of 0.35 microM. In the range of 1.0-100 microM, the catalytic reduction current of H(2)O(2) was proportional to H(2)O(2) concentration. The apparent Michaelis-Menten constant (k(m)(app)) of the biosensor was calculated to be 21.8 microM, exhibiting a high enzymatic activity and affinity for H(2)O(2).