Distribution of Subgingival Bacteria in Chronic Periodontitis Patients Correlated with IgA Nephropathy.

BACKGROUND: Several studies indicated that chronic periodontitis (CP) and its subgingival bacteria correlated with IgA nephropathy (IgAN). Previous research has shown that prevalence of IgAN in chronic periodontitis patients is significantly higher than that in non CP patients in Xinjiang especially in ethnic Uyghur. The aim of this study is to investigate the distribution of plaque bacterial microbes in CP and IgAN patients and to find correlation between CP and IgAN. METHODS: All of the subgingival plaque samples including 7 healthy controls (N group), 8 CP patients, 14 IgAN patients, and 14 CP with IgAN patients were obtained from ethnic Uyghur people. To investigate the distribution of plaque microbe in Uyghur CP and IgAN patients, the 16s rRNA sequencing and comparative analysis of subgingival bacteria were performed. RESULTS: There were no statistically differences in the community richness estimator (Chao) and the diversity estimator (Shannon index) among four groups. The abundance of Burkholderiales (order), Ottowia (genus) in the plaque microbes were significantly higher in CP with IgAN patients than CP patients. The abundance of Eubacterium (genus) was significantly higher in CP with IgAN patients than IgAN patients. The abundance of Veillonella (genus) was significantly higher while Streptococcus (genus), Tannerella (genus) were significantly lower in CP patients than healthy volunteers. CONCLUSIONS: The composition and abundance of subgingival plaque microbes in Uyghur CP and IgAN patients were significantly different at several levels. Which suggested that abundance of subgingival bacteria is correlated to CP and IgAN.

Evaluation of compost quality and the environmental effects of semipermeable membrane composting with poultry manure using sawdust or mushroom residue as the bulking agent.

Herein, the effects of different bulking agents (sawdust and mushroom residue), on compost quality and the environmental benefits of semipermeable film composting with poultry manure were investigated. The results show that composting with sawdust as the bulking agent resulted in greater efficiency and more cost benefits than composting with mushroom residue, and the cost of sawdust for treating an equal volume of manure was only 1/6 of that of mushroom residue. Additionally, lignin degradation and potential carbon emission reduction in the sawdust group were better than those in the mushroom residue group, and the lignin degradation efficiency of the bottom sample in the sawdust group was 48.57 %. Coupling between lignin degradation and potential carbon emission reduction was also closer in sawdust piles than in mushroom residue piles, and sawdust is more environmentally friendly. The abundance of key functional genes was higher at the bottom of each pile relative to the top and middle. Limnochordaceae, Lactobacillus and Enterococcus were the core microorganisms involved in coupling between lignin degradation and potential carbon emission reduction, and the coupled relationship was influenced by electric conductivity, ammonia nitrogen and total nitrogen in the compost piles. This study provides important data for supporting bulking agent selection in semipermeable film composting and for improving the composting process. The results have high value for compost production and process application.

Subcutaneous Implantable Microneedle System for the Treatment of Alzheimer's Disease by Delivering Donepezil.

To alleviate the dilemma of drug administration in Alzheimer's disease (AD) patients, it is of great significance to develop a new drug delivery system. In this study, a subcutaneously implanted microneedle (MN) device with a swellable gelatin methacryloyl (GelMA) needle body and a dissolvable polyvinyl alcohol (PVA) backing layer was designed. The backing layer quickly dissolved once the MN was introduced into the subcutaneous, and the hydrogel needles were implanted in the subcutaneous to enable prolonged drug release. Compared with oral administration, the MN system offers the benefits of a high administration rate, a fast onset of effect, and a longer duration of action. By detecting the concentration of acetylcholine (ACH) and Aß 1-42, it was found that MN administration exhibited a stronger therapeutic effect. The biological safety of the MN system was also assessed, and no obvious signs of hemolysis, cytotoxicity, and inflammatory reaction were observed. Together, these findings suggested that the MN system is a convenient, efficient, and safe method of delivering donepezil hydrochloride (DPH) and may provide AD patients with a novel medicine administration option.

In Vivo Antibacterial Efficacy of Nitric Oxide-Releasing Hyperbranched Polymers against Porphyromonas gingivalis.

The in vivo antibacterial activity of NO-releasing hyperbranched polymers was evaluated against Porphyromonas gingivalis, a key oral pathogen associated with periodontitis, using a murine subcutaneous chamber model. Escalating doses of NO-releasing polymers (1.5, 7.5, and 37.5 mg/kg) were administered into a P. gingivalis-infected chamber once a day for 3 days. Chamber fluids were collected on day 4, with microbiological evaluation indicating a dose-dependent bactericidal action. In particular, NO-releasing polymers at 37.5 mg/kg (1170 µg of NO/kg) achieved complete bacterial eradication (>6-log reduction in bacterial viability), demonstrating greater efficacy than amoxicillin (∼4-log reduction in bacterial viability), a commonly used antibiotic. Time-kill assays further revealed that largest dose (37.5 mg/kg; 1170 µg of NO/kg) resulted in ∼3-log killing of P. gingivalis after only a single dose. Based on these results, the potential clinical utility of NO-releasing hyperbranched polymers appears promising, particularly for oral health applications.

Juxta-articular tumoral calcinosis associated with the temporomandibular joint: a case report and concise review.

BACKGROUND: Tumoral calcinosis is an uncommon clinicopathological condition which is characterized by the formation of calcium salt deposition in intra-articular or peri-articular soft tissues. It usually presents as a focal growth of hard tissue, either solitary or multiple, beneath the skin and connective tissue. Diagnostic techniques mainly include clinical and radiographic evaluation. The most commonly involved locations include the hip, elbow, shoulder and knee. Involvement of the head and neck regions are far less common. There have been 5 case reports of temporomandibular joint involvement in the literature so far. CASE PRESENTATION: We present a case report which describes the diagnosis and management of a 59 year old female patient with chronic right temporomandibular joint pain and localized bony hard swelling over the right pre-auricular region. Patient retained normal range of motion and mouth opening. Computed tomography taken showed a radio-opaque juxta-articular ovoid mass over the right pre-auricular region in close proximity but not fused to the mandibular condyle. Surgical excision was performed for this swelling via a pre-auricular approach under general anaesthesia. Histological examination performed confirmed the diagnosis of tumoral calcinosis. Pain at the right temporomandibular joint was resolved after the surgery. Serum calcium and phosphate levels were normal in this patient. CONCLUSION: Surgical excision is the primary treatment modality for tumoral calcinosis. Tumoral calcinosis may be associated with elevated serum calcium and phosphate levels. In patients with elevated serum electrolytes, it is important to consider the overall systemic health in management of this condition. Management of serum electrolytes levels plays a role in reducing recurrence rates. This case report and review aims to discuss the diagnosis, treatment and overall systemic management of this rare condition.

Adaptive laboratory evolution of ethanologenic Zymomonas mobilis strain tolerant to furfural and acetic acid inhibitors.

Furfural and acetic acid from lignocellulosic hydrolysates are the prevalent inhibitors to Zymomonas mobilis during cellulosic ethanol production. Developing a strain tolerant to furfural or acetic acid inhibitors is difficul by using rational engineering strategies due to poor understanding of their underlying molecular mechanisms. In this study, strategy of adaptive laboratory evolution (ALE) was used for development of a furfural and acetic acid-tolerant strain. After three round evolution, four evolved mutants (ZMA7-2, ZMA7-3, ZMF3-2, and ZMF3-3) that showed higher growth capacity were successfully obtained via ALE method. Based on the results of profiling of cell growth, glucose utilization, ethanol yield, and activity of key enzymes, two desired strains, ZMA7-2 and ZMF3-3, were achieved, which showed higher tolerance under 7 g/l acetic acid and 3 g/l furfural stress condition. Especially, it is the first report of Z. mobilis strain that could tolerate higher furfural. The best strain, Z. mobilis ZMF3-3, has showed 94.84% theoretical ethanol yield under 3-g/l furfural stress condition, and the theoretical ethanol yield of ZM4 is only 9.89%. Our study also demonstrated that ALE method might also be used as a powerful metabolic engineering tool for metabolic engineering in Z. mobilis. Furthermore, the two best strains could be used as novel host for further metabolic engineering in cellulosic ethanol or future biorefinery. Importantly, the two strains may also be used as novel-tolerant model organisms for the genetic mechanism on the "omics" level, which will provide some useful information for inverse metabolic engineering.

Toward a solid microneedle patch for rapid and enhanced local analgesic action.

Analgesic creams find widespread application as adjuncts for localized anesthesia prior to surgical procedures. Nevertheless, the onset of analgesic action is protracted due to the skin barrier's inherent characteristics, which necessitates prolonged intervals of patient and clinician waiting, consequently impinging upon patient compliance and clinician workflow efficiency. In this work, a biodegradable microneedles (MNs) patch was introduced to enhance the intradermal administration of lidocaine cream to achieve rapid analgesia through a minimally invasive and conveniently accessible modality. The polylactic acid (PLA) MNs were mass-produced using a simple hot-pressing method and served the purpose of creating microchannels across the skin's surface for rapid absorption of lidocaine cream. Optical and electron microscopes were applied to meticulously scrutinize the morphology of the fabricated MNs, and the comprehensive penetration tests involving dynamometer tests, evaluation on porcine cadaver skin, artificial film, optical coherence tomography (OCT), transepidermal water loss, and analysis on rats' skins, demonstrated the robust mechanical strength of PLA MNs for successful intradermal penetration. The behavioral pain sensitivity tests on living rats using Von Frey hair filaments revealed that the MN-assisted lidocaine treatment expeditiously accelerated the onset of action from 40 to 10 min and substantially enhanced the efficacy of localized anesthesia. Furthermore, different treatment protocols encompassing the sequence of drug application relative to MN treatment, MN dimensions, and the frequency of MN insertions exhibited noteworthy influence on the resultant local anesthesia efficacy. Together, these results demonstrated that the lidocaine cream followed by diverse PLA MN treatments would be a promising strategy for rapid clinical local anesthesia with wide-ranging applications.

Assessing the structural stability and drug encapsulation efficiency of poly(ethylene glycol)-poly(L-lactic acid) nanoparticles loaded with atorvastatin calcium: Based on dissipative particle dynamics.

Block polymer micelles have been proven highly biocompatible and effective in improving drug utilization for delivering atorvastatin calcium. Therefore, it is of great significance to measure the stability of drug-loading nano micelles from the perspective of block polymer molecular sequence design, which would provide theoretical guidance for subsequent clinical applications. This study aims to investigate the structural stability of drug-loading micelles formed by two diblock/triblock polymers with various block sequences through coarse-grained dissipative particle dynamics (DPD) simulations. From the perspectives of the binding strength of poly(L-lactic acid) (PLLA) and polyethylene glycol (PEG) in nanoparticles, hydrophilic bead surface coverage, and the morphological alteration of nanoparticles induced by shear force, the ratio of hydrophilic/hydrophobic sequence length has been observed to affect the stability of nanoparticles. We have found that for diblock polymers, PEG3kda-PLLA2kda has the best stability (corresponding hydrophilic coverage ratio is 0.832), while PEG4kda-PLLA5kda has the worst (coverage ratio 0.578). For triblock polymers, PEG4kda-PLLA2kda-PEG4kda has the best stability (0.838), while PEG4kda-PLLA5kda-PEG4kda possesses the worst performance (0.731), and the average performance on stability is better than nanoparticles composed of diblock polymers.

Anodic TiO2 nanotubular arrays with pre-synthesized hydroxyapatite--an effective approach to enhance the biocompatibility of titanium.

Electrochemically anodized TiO2 nanotubular arrays can provide large surface areas for biological species attachment. In order to further enhance the biocompatibility of Ti medical implants, we deposited a pre-synthesized hydroxyapatite inside and on the nanotubular arrays, and examined the biocompatibility of the anodized TiO2 nanotubular arrays with pre-synthesized hydroxyapatite by in vitro assessment in simulated body fluid, and in vitro cell culture. The results showed that the hydroxyapatite coating was able to be induced on TiO2 nanotubular arrays with pre-synthesized hydroxyapatite within 5 days while only a thin film composed of calcium phosphorous chemicals formed on as-formed TiO2 nanotubular arrays. The cell culture evaluation further proved the enhancement of cell attachment and proliferation on TiO2 nanotubular arrays with pre-synthesized hydroxyapatite as opposed to those without pre-synthesized hydroxyapatite. The present study proves that formation of TiO2 nanotubular arrays with pre-synthesized hydroxyapatite a promising method to enhance the biocompatibility of Ti implants.

[Preparation technology of total coumarins from Laportea bulbifera].

OBJECTIVE: To investigate the preparation process of total coumarins from Laportea bulbifera. METHODS: The optimum condition for the extraction of total coumarins was studied using the orthogonal test, and the extracts was purled with different kinds of macroporous resins. The content of total coumarins was detected by ultraviolet spectrophotometry. RESULTS: The optimum extraction process was as follows: three-time circumfluence with 4 times volume of 75% ethanol for 1.5 h each time. HPD300 macroporous resin was the optimum one for the separation and purification of total coumarins. The extraction condition was loading 30 mL of 0.4 g/mL the crude drug, flowing at 2BV/h, then edulcorating with 4 times volume of distilled water and eluting with the same volume of 75% ethanol. The yield rate was more than 52%. CONCLUSION: This method is suitable for the preparation of total coumarins in Laportea bulbifera, and the process is stable and repeatable.

Characterization of silver diamine fluoride cytotoxicity using microfluidic tooth-on-a-chip and gingival equivalents.

OBJECTIVE: This study aims to characterize the cytotoxicity potential of silver diamine fluoride (SDF) on dental pulp stem cells (DPSC) and gingival equivalents. METHODS: DPSC cultured on 96-well plates was exposed directly to SDF (0.0001-0.01%) and cell viability (IC50) quantified. Effect of SDF on DPSC viability under flow (with dentin barrier) conditions was evaluated using a custom-designed microfluidic "tooth-on-a-chip". Permeability of dentin discs (0.5-1.5 mm thickness) was evaluated using lucifer yellow permeation assay. Dentin discs were treated with 38% SDF (up to 3 h), and cell viability (live/dead assay) of the DPSC cultured in the inlet (unexposed) and outlet (exposed) regions of the pulp channel was evaluated. To assess the mucosal corrosion potential, gingival equivalents were treated with 38% SDF for 3 or 60 min (OECD test guideline 431) and characterized by MTT assay and histomorphometric analysis. RESULTS: DPSC exposed directly to SDF showed a dose-dependent reduction in cell viability (IC50: 0.001%). Inlet channels (internal control) of the tooth-on-a-chip exposed to PBS and SDF-exposed dentin discs showed> 85% DPSC viability. In contrast, the outlet channels of SDF-exposed dentin discs showed a decreased viability of< 31% and 0% (1.5 and ≤1.0 mm thick dentin disc, respectively) (p < 0.01). The gingiva equivalents treated with SDF for 3 and 60 min demonstrated decreased epithelial integrity, loss of intercellular cohesion and corneal layer detachment with significant reduction in intact epithelial thickness (p < 0.05). SIGNIFICANCE: SDF penetrated the dentin (≤1 mm thick) inducing significant death of the pulp cells. SDF also disrupted gingival epithelial integrity resulting in mucosal corrosion.

Coil and n-butyl-2-cyanoacrylate migration into the stomach after TIPS for gastroesophageal variceal bleeding: a case report and literature review.

BACKGROUND: Transjugular intrahepatic portosystemic shunt (TIPS) is a well-established therapeutic option for the management of variceal hemorrhage in patients with cirrhosis. The simultaneous migration of the coil and n-butyl-2-cyanoacrylate (NBCA) is an extremely rare but significant complication after TIPS. Because of its rare presentation, there are currently no definitive recommendations for the management of this condition. CASE PRESENTATION: A 46-year-old man with hepatitis B cirrhosis underwent TIPS placement for uncontrolled gastroesophageal varix (GEV) bleeding secondary to portal hypertension in August 2018. During the procedure, large GEVs were embolized using a coil and NBCA. After a year, coil and NBCA migration into the stomach was observed. Attempts to remove the coil using biopsy forceps during esophagogastroduodenoscopy failed. The patient refused further intervention on the coil to prevent further complications and received conservative therapy instead. Close surveillance with endoscopy is recommended for detecting coils and varices. CONCLUSIONS: The present case reports an extremely rare but significant complication after TIPS, which highlights the management and follow-up recommendation for such rare complications. Our experience may provide guidance for the management of future similar cases and stimulate discussion about treatment methods of similar patients.

Location of supraorbital foramen/notch and infraorbital foramen with reference to soft- and hard-tissue landmarks.

The purpose of the present study was to determine the locations of the supraorbital foramen (SOF) and the infraorbital foramen (IOF) relative to soft- and hard-tissue landmarks. It will provide more accurate data for dental and facial surgery. Twenty embalmed adult cadavers (40 sides; 16 men, 4 women) were dissected to expose the SOFs and IOFs, and another 46 skulls (92 sides) were also measured for further study. The locations of the SOFs and IOFs were evaluated with direct and photographic measurements. The data gained were analyzed by statistical method. The horizontal distances between the SOFs/IOFs and the medial canthus to the distance between the medial canthus and the lateral canthus ratios have been measured, and their confidence intervals are 0.22 to 0.31 and 0.34 to 0.49, respectively, and their linear regression equations are EF = 0.58 CF + 25.02 (unit: mm) and EF = 0.51 DG + 24.20 (unit: mm). The vertical distance between IOFs/SOFs and the medial/lateral canthi are 25.09 ± 3.36 mm/23.91 ± 3.31 mm and 25.75 ± 3.34 mm/26.93 ± 3.88 mm, respectively. The horizontal angle between IOFs/SOFs and the medial/lateral canthi are 72.54 ± 7.13 degrees, 66.77 ± 5.17 degrees, 47.45 ± 6.57 degrees, 54.69 ± 8.38 degrees, respectively. Based on the hard tissues, The SOF localized 20.55 ± 3.24 mm medial and 13.78 ± 2.60 mm superior to the zygomaticofrontal suture. And the horizontal angle between them is 56.04 ± 6.87 degrees. The IOF localized 18.52 ± 2.30 mm medial and 30.79 ± 3.29 inferior to the zygomaticofrontal suture. The horizontal angle between them is 31.06 ± 4.33 degrees. We also found that most (96.81%) of the IOFs were located below the middle line of the zygomatic arch. These results may provide more detailed information about the locations of SOF and IOF. And they will facilitate prediction of the locations of IOF and SOF in clinical procedure.

Location of mental foramen based on soft- and hard-tissue landmarks in a chinese population.

The purpose of the present study was to determine the location of the mental foramen (MF) based on soft- and hard-tissue landmarks, to facilitate prediction of the location of this structure during facial and dental surgery. Forty-two hemispheres of 21 adult cadavers (16 men and 5 women; aged 30-75 years) were dissected to expose the MF. The locations of the MFs were evaluated with direct and photographic measurements. Most of the MFs presented a single foramen (95%), except for only 2 cases with double foramina (5%). The MFs localized 23.38 +/- 2.00 mm inferior and 3.55 +/- 1.70 mm medial to the cheilion in the front view while 23.59 +/- 2.11 mm inferior and 7.19 +/- 3.03 mm posterior to the cheilion in the lateral view. Based on the hard-tissue landmarks, we found that most of the MFs localized inferior the second premolar in most of the cases (73.8%), and the MFs localized 23.34 +/- 2.39 mm below the cusp tip of the second premolar, 16.56 +/- 2.53 mm below the inferior alveoli, and 15.56 +/- 1.74 mm superior the bottom of the mandible. The position of the MF varied from 8.7 degrees medial to 15.5 degrees posterior in the vertical angle with the change of surgical body position from supine to lay-side position. Our results may provide a more detailed information to predict the location of the MFs.

An experimental murine model to study periodontitis.

Periodontal disease (PD) is a common dental disease associated with the interaction between dysbiotic oral microbiota and host immunity. It is a prevalent disease, resulting in loss of gingival tissue, periodontal ligament, cementum and alveolar bone. PD is a major form of tooth loss in the adult population. Experimental animal models have enabled the study of PD pathogenesis and are used to test new therapeutic approaches for treating the disease. The ligature-induced periodontitis model has several advantages as compared with other models, including rapid disease induction, predictable bone loss and the capacity to study periodontal tissue and alveolar bone regeneration because the model is established within the periodontal apparatus. Although mice are the most convenient and versatile animal models used in research, ligature-induced periodontitis has been more frequently used in large animals. This is mostly due to the technical challenges involved in consistently placing ligatures around murine teeth. To reduce the technical challenge associated with the traditional ligature model, we previously developed a simplified method to easily install a bacterially retentive ligature between two molars for inducing periodontitis. In this protocol, we provide detailed instructions for placement of the ligature and demonstrate how the model can be used to evaluate gingival tissue inflammation and alveolar bone loss over a period of 18 d after ligature placement. This model can also be used on germ-free mice to investigate the role of human oral bacteria in periodontitis in vivo. In conclusion, this protocol enables the mechanistic study of the pathogenesis of periodontitis in vivo.

GWAS for Interleukin-1ß levels in gingival crevicular fluid identifies IL37 variants in periodontal inflammation.

There is no agnostic GWAS evidence for the genetic control of IL-1ß expression in periodontal disease. Here we report a GWAS for "high" gingival crevicular fluid IL-1ß expression among 4910 European-American adults and identify association signals in the IL37 locus. rs3811046 at this locus (p = 3.3 × 10-22) is associated with severe chronic periodontitis (OR = 1.50; 95% CI = 1.12-2.00), 10-year incident tooth loss (≥3 teeth: RR = 1.33; 95% CI = 1.09-1.62) and aggressive periodontitis (OR = 1.12; 95% CI = 1.01-1.26) in an independent sample of 4927 German/Dutch adults. The minor allele at rs3811046 is associated with increased expression of IL-1ß in periodontal tissue. In RAW macrophages, PBMCs and transgenic mice, the IL37 variant increases expression of IL-1ß and IL-6, inducing more severe periodontal disease, while IL-37 protein production is impaired and shows reduced cleavage by caspase-1. A second variant in the IL37 locus (rs2708943, p = 4.2 × 10-7) associates with attenuated IL37 mRNA expression. Overall, we demonstrate that IL37 variants modulate the inflammatory cascade in periodontal disease.

Nanotubular surface modification of metallic implants via electrochemical anodization technique.

Due to increased awareness and interest in the biomedical implant field as a result of an aging population, research in the field of implantable devices has grown rapidly in the last few decades. Among the biomedical implants, metallic implant materials have been widely used to replace disordered bony tissues in orthopedic and orthodontic surgeries. The clinical success of implants is closely related to their early osseointegration (ie, the direct structural and functional connection between living bone and the surface of a load-bearing artificial implant), which relies heavily on the surface condition of the implant. Electrochemical techniques for modifying biomedical implants are relatively simple, cost-effective, and appropriate for implants with complex shapes. Recently, metal oxide nanotubular arrays via electrochemical anodization have become an attractive technique to build up on metallic implants to enhance the biocompatibility and bioactivity. This article will thoroughly review the relevance of electrochemical anodization techniques for the modification of metallic implant surfaces in nanoscale, and cover the electrochemical anodization techniques used in the development of the types of nanotubular/nanoporous modification achievable via electrochemical approaches, which hold tremendous potential for bio-implant applications. In vitro and in vivo studies using metallic oxide nanotubes are also presented, revealing the potential of nanotubes in biomedical applications. Finally, an outlook of future growth of research in metallic oxide nanotubular arrays is provided. This article will therefore provide researchers with an in-depth understanding of electrochemical anodization modification and provide guidance regarding the design and tuning of new materials to achieve a desired performance and reliable biocompatibility.

Bamboo: a new source of carbohydrate for biorefinery.

Bamboo is perennial woody grass, which distributed widely in the world and belonged to the Gramineae family and Bambuseae subfamily. It may be consider as a candidate lignocellulosic substrate for bio-ethanol production for its environmental benefits and higher annual biomass yield. The conversion of bamboo into bio-ethanol, bio-methane, natural food, flavonoids, and functional xylo-oligosaccharides production were reviewed in this paper. Future prospects for research include pretreatment, enzymatic hydrolysis and fermentation will also be performed to improve the whole process of ethanol production more economical. And revealing the molecular regulation mechanism of the fast growth of bamboo will provide chance for improving bamboo or other energy plants biomass yield through genetic engineering.

Composite nanofibers doped with a phosphorescent Re(I) complex having restricted conjugation plane in its diamine ligand: preparation, characterization, photophysical property and oxygen-sensing performance.

In this paper, we report a Re(I) complex of Re(CO)3(Cl-PYO)Br, where Cl-PYO stands for 2-(4-chlorophenyl)-5-(pyridin-2-yl)-1,3,4-oxadiazole, including its synthesis, identification, molecular structure, theoretical calculation and photophysical character. Re(CO)3(Cl-PYO)Br is found to be a yellow emitter with long excited state lifetime in pure N2 atmosphere. Theoretical calculation result suggests that this emission comes from a triplet metal-to-ligand-charge-transfer excited state. By doping Re(CO)3(Cl-PYO)Br into a polymer supporting matrix of poly(vinylpyrrolidone), the emission of the resulted composite materials is found to be sensitive towards various oxygen concentrations. The maximum sensitivity is obtained to be 7.88. Owing to the porous structure of fibrous poly(vinylpyrrolidone) matrix, a short response time of 11s towards molecular oxygen is also realized with high photostability.

Enhancement of the capability of hydroxyapatite formation on Zr with anodic ZrO2 nanotubular arrays via an effective dipping pretreatment.

Hydroxyapatite (HA) depositions on metallic biomedical implants are widely applied to generate bioactive surfaces in simulated biological environments. Highly ordered anodic ZrO2 nanotubes have attracted increasing interest for biomedical applications. However, previous reports showed that at least 14-28 days were required to obtain HA coating on ZrO2 nanotubular arrays under biomimetic condition, thus capability to grow HA coating on ZrO 2nanotubular at room temperature needs to be enhanced. In the present work, we demonstrate that ZrO2 nanotubular arrays are suitable for an effective dipping treatment to induce more rapid HA coating. A series of ZrO2 nanotubular arrays having different dimensions were fabricated in fluoride containing electrolyte. Then, we used a dipping treatment for biomimetic formation of an adhesive HA coating on the nanotubular arrays. The coatings formed rapidly using this procedure under biomimetic conditions and did not require a high-temperature annealing process. The as-formed ZrO2 nanotubular arrays were treated using several dip-and-dry steps, through which the nanotubular arrays were filled and covered with calcium phosphate (CaP) nucleation sites. The specimens readily grew HA once immersed in the simulated biological fluid after 2 days immersion. The carbonated HA coating had several micron thickness after 8 days of immersion while only a thin layer of CaP were observed on annealed ZrO2 nanotubes immersed in the same solution for the same duration. Tensile testing showed that bonding strength between HA coating and substrate was 21.6 ± 1.6 MPa. This treatment dramatically improves efficiency for promoting HA formation on anodic ZrO2 nanotubes at room temperature.