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Solenopsis invicta Buren, also known as the red imported fire ant (RIFA), has had a large negative impact on human and livestock health. However, few studies have further investigated the influence of human land use, which is an important factor affecting the habitats of insects, on the expansion of RIFAs. In addition, there is a lack of knowledge of the empirical associations between RIFA diffusion and land use within countries. Therefore, the objectives of this study were to provide an approach to delineate the areas of RIFA infestations and explore how land use influences the spatiotemporal diffusion of S. invicta. We used RIFA data from 2008 to 2015 from the RIFA surveillance system, which was conducted by the National RIFA Control Center in Taiwan. Two regions in Taiwan with different RIFA infestation levels were investigated. The ordinary kriging method was applied to show the spatial intensity of RIFAs, and the extreme distance estimator method was applied to determine the critical dispersal distances, which showed the distance of the highest probability of RIFAs in two consecutive years. In addition, network analyses were used to identify RIFA invasion routes between land‐use types. Finally, bivariate local indicators of spatial association were used to capture the invasion process in time and space. The results showed, paddy fields, main roads, and warehouses were identified as the top three land‐use types of diffusion sources. On average, the critical RIFA dispersal distances were 600 and 650 m in two consecutive years in high‐ and low‐infestation regions, respectively. Finally, RIFAs were likely to diffuse between main roads and warehouses in the low‐infestation region. Therefore, it is suggested that RIFA control activities be implemented at least 600 m from the observed spot. Additionally, control activities should be conducted on the identified three land‐use types of diffusion sources in the high‐infestation region, and the roadsides between main roads and warehouses in the low‐infestation region to prevent the accidental spread of RIFAs., Hot spot and invasive areas of RIFAs in Taoyuan by years: (a) 2012–2013, (b) 2013–2014, and (c) 2014–2015. Red blocks are hot spots, indicating high intensity of S. invicta for both consecutive years. Blue blocks represent diffusion areas that had a significantly higher intensity of S. invicta for the later year.

In this paper, we propose a fundamental timing strategy in both U.S. and Chinese stock market to trade the fundamental sorted portfolios such as value and profitability portfolios in the time series dimension. We find that fundamental timing strategies based on moving average (MA) timing signals could generate substantial performance improvements relative to corresponding buy-and-hold fundamental strategies. The annualized average return of the 20-day MA fundamental timing strategies reaches about 37% with Sharpe ratio nearly 1.30. These findings are robust to Fama-French factor model adjustment, alternative lag lengths of MA signals, holding days, and transaction costs. Moreover, we find that the fundamental timing premium cannot be explained by market timing ability or business cycle, and fundamental timing is more profitable among firms with high idiosyncratic volatility and high illiquidity measures.

The rapid re-endothelialization of the vascular stent surface is desirable for preventing thrombosis or reducing restenosis. Many biological factors that promote the biological behavior of endothelial cells have been used for the surface modification of stents. Vascular endothelial growth factor (VEGF), which plays an important role in angiogenesis, induces strong vascular growth. In this study, we investigated different VEGF concentrations (50 to 500 ng/ml) to determine the optimum concentration for biocompatibility. First, VEGF-loaded heparin/poly-l-lysine (Hep-PLL) nanoparticles were created by electrostatic interactions. Then, the VEGF-loaded nanoparticles were immobilized on dopamine-coated 316 L stainless steel (SS) surfaces. The physical and chemical properties of the modified surface were characterized and the biocompatibility was evaluated in vitro. The results indicated that the VEGF-loaded nanoparticles were immobilized successfully on the 316LSS surface, as evidenced by the results of Alcian Blue staining and water contact angle (WCA) measurements. The low platelet adhesion and activation indicated that the modified surfaces had good blood compatibility. The modified surfaces showed a good inhibitory effect on smooth muscle cells, indicating that they inhibited tissue hyperplasia. In addition, the modified surfaces significantly promoted endothelial cell adhesion, proliferation, migration, and biological activity, especially VEGF concentration was 350 ng/ml (NPV350). The optical VEGF concentration of the surface modified Hep-PLL nanoparticles was 350 ng/ml. The proposed method shows promise for potential applications for cardiovascular devices.

Diabetic retinopathy (DR) is a leading cause of acquired blindness among adults. High glucose (HG) induces oxidative injury and apoptosis in retinal ganglion cells (RGCs), serving as a primary pathological mechanism of DR. MIND4-17 activates nuclear-factor-E2-related factor 2 (Nrf2) signaling via modifying one cysteine (C151) residue of Kelch-like ECH-associated protein 1 (Keap1). The current study tested its effect in HG-treated primary murine RGCs. We show that MIND4-17 disrupted Keap1-Nrf2 association, leading to Nrf2 protein stabilization and nuclear translocation, causing subsequent expression of key Nrf2 target genes, including heme oxygenase-1 and NAD(P)H quinone oxidoreductase 1. Functional studies showed that MIND4-17 pretreatment significantly inhibited HG-induced cytotoxicity and apoptosis in primary murine RGCs. Reactive oxygen species production and oxidative injury in HG-treated murine RGCs were attenuated by MIND4-17. Nrf2 silencing (by targeted small interfering RNA) or knockout (by CRISPR/Cas9 method) abolished MIND4-17-induced RGC cytoprotection against HG. Additionally, Keap1 knockout or silencing mimicked and abolished MIND4-17-induced activity in RGCs. In vivo, MIND4-17 intravitreal injection activated Nrf2 signaling and attenuated retinal dysfunction by light damage in mice. We conclude that MIND4-17 activates Nrf2 signaling to protect murine RGCs from HG-induced oxidative injury.

Several studies have demonstrated the efficacy of house dust mite (HDM) immunotherapy in allergic rhinitis (AR). We aimed to compare the efficacy and safety of 2 commercial HDM extracts in a Chinese AR population.This was an open-label study. HDM-associated AR patients were randomized into Dermatophagoides pteronyssinus (Dp) extracts (Alutard SQ; ALK, Hørsholm, Denmark) and Dp/Dermatophagoides farinae (Df) extracts (NovoHelisen Depot [NHD]; Allergopharma, Reinbek, Germany) groups. All patients received subcutaneous injections for 1 year, and were followed every 3 months during that 1-year period. Symptom score, medication score, and adverse reactions were recorded. The primary endpoint was the total combined symptom and medication score (CSMS) during the efficacy evaluation period. Blood samples were taken for specific immunoglobulin E (IgE), IgG4, and IgE-blocking factor tests at baseline and after the 1-year treatment.A total of 230 AR patients were randomized; 29 patients dropped out. Analysis of the primary endpoint demonstrated significant reductions in CSMS of 1.8 vs 3.1 (p0.001) in the Alutard group and 1.8 vs 3.3 (p0.001) in the NHD group compared with baseline. The 2 groups presented equal effectiveness with regard to CSMS, symptom score, and medication score (p0.05). The treatment was well tolerated in both groups; 17 (14.8%) patients experienced systemic reactions (SRs) in the Alutard group and 13 (11.3%) in the NHD group. The rates of SRs showed no difference in the 2 groups (p0.05), and no anaphylaxis occurred. IgG4 and IgE-blocking factor to Dp and Df were increased significantly in both groups after the 1-year treatment.Our study confirmed the equal efficacy and safety profile of both commercial extracts in HDM-associated AR patients.

Skin surface is constantly exposed to environmental and secreted stressors such as UV, air pollution and peroxidized sebum. The current study aims to use reconstructed human skin equivalents to demonstrate topical stressor-induced hyperpigmentation and evaluate bioactives' potential protective effect. Given that polycyclic aromatic hydrocarbons are representative airborne particle-bound organic compounds with known relevance to pigmentation pathways, benzo(a)pyrene was selected as surrogate environmental toxin. On the other hand, squalene monohydroperoxides are well-characterized sebum peroxidation product under UV and pollutant exposure, thus are used as another representative skin stressor. With 3-day continuous exposure, 30 pmol/cm2 of benzo(a)pyrene and 3.4 nmol/cm2 of squalene monohydroperoxides induced significant viability loss, inflammatory response, and approximately 10 shades of pigmentation increase in pigmented living skin equivalents. At the same time, pretreatment and co-treatment with 12-hydroxystearic acid (12-HSA, 20 μmol/L) or niacinamide (5 mmol/L) ameliorated such stressor-induced consequences. Niacinamide was particularly effective against benzo(a)pyrene damage, probably as a substrate for important NAD+ dependent detoxification pathways, while 12-HSA was potent against squalene monohydroperoxides through barrier enhancing, anti-inflammatory, and anti-oxidative mechanisms. In summary, topical stressor-induced hyperpigmentation was achieved in vitro, with known bioactives showing protective benefits.

Phenotype switching is a characteristic response of vascular smooth muscle cells (vSMCs) to the dynamic microenvironment and contributes to all stages of atherosclerotic plaque. Here, we immersed pure magnesium and AZ31 alloy in the completed medium under cell culture condition, applied the resultant leaching extracts to the isolated contractile rat aortic vSMCs and investigated how vSMCs phenotypically responded to the degradation of the magnesium-based stent materials. vSMCs became more proliferative and migratory but underwent more apoptosis when exposed to the degradation products of pure magnesium; while the AZ31 extracts caused less cell division but more apoptosis, thus slowing cell moving and growing. Noticeably, both leaching extracts dramatically downregulated the contractile phenotypic genes at mRNA and protein levels while significantly induced the inflammatory adhesive molecules and cytokines. Exogenously added Mg ions excited similar transformations of vSMCs. With the liberation or supplementation of Mg2+ , the expression patterns of the pro-contractile transactivator myocardin and the pro-inflammatory transcriptional factor kruppel-like factor 4 (KLF4) were reversed. Overall, the degradation of the Mg-based materials would evoke a shift of the contractile vSMCs to an inflammatory phenotype via releasing Mg ions to induce a transition from the phenotypic control of vSMCs by the myocardin to that by the KLF4. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 988-1001, 2019.

Endothelium can secrete vasoactive mediators and produce specific extracellular matrix, which contribute jointly to the thromboresistance and regulation of vascular cell behaviors. From a bionic point of view, introducing endothelium‐like functions onto cardiovascular stents represents the most effective means to improve hemocompatibility and reduce late stent restenosis. However, current surface strategies for vascular stents still have limitations, like the lack of multifunctionality, especially the monotony in endothelial‐mimic functions. Herein, a layer‐by‐layer grafting strategy to create endothelium‐like dual‐functional surface on cardiovascular scaffolds is reported. Typically, a nitric oxide (NO, vasoactive mediator)‐generating compound and an endothelial polysaccharide matrix molecule hyaluronan (HA) are sequentially immobilized on allylamine‐plasma‐deposited stents through aqueous amidation. In this case, the stents could be well‐engineered with dual endothelial functions capable of remote and close‐range regulation of the vascular microenvironment. The synergy of NO and endothelial glycocalyx molecules leads to efficient antithrombosis, smooth muscle cell (SMC) inhibition, and perfect endothelial cell (EC)‐compatibility of the stents in vitro. Moreover, the dual‐functional stents show efficient antithrombogenesis ex vivo, rapid endothelialization, and long‐term prevention of restenosis in vivo. Therefore, this study will provide new solutions for not only multicomponent surface functionalization but also the bioengineering of endothelium‐mimic vascular scaffolds with improved clinical outcomes., An endothelium‐mimicking coating NO‐releasing property and grafted glycocalyx molecules on a cardiovascular stent is reported. The dual functions endow the stent with antithrombosis, smooth muscle cell (SMC) inhibition, and endothelial cell (EC)‐compatibility, which result in efficient antithrombogenesis ex vivo, rapid endothelialization, and long‐term prevention of restenosis in vivo.

BACKGROUND Allergen immunotherapy (AIT) is still the only causal treatment for allergic diseases. However, conventional subcutaneous immunotherapy (SCIT) administration schedules are time-consuming and patient nonadherence is a major barrier to achieving a satisfactory therapeutic effect. Our study aimed to analyze the causes leading to discontinuation of SCIT and to determine risk factors associated with nonadherence in respiratory allergies. METHODS This was a prospective study. Patients with respiratory allergies who had received standardized dust mite SCIT were enrolled from January 2012 to January 2014. And a follow-up study on these subjects was conducted via telephone interviews on an interval of 3 months and online communication through social network applications. Reasons for discontinuation were documented when patients claimed to stop treatment. RESULTS A total of 311 patients were enrolled in the study. The adherence rate at year 3 was 64.6%. Fifty-nine patients (19.0%) dropped out in year 1, 31 (10.0%) in year 2, and 20 (6.4%) in year 3. Reasons for nonadherence included inconvenience (32.7%), ineffectiveness (25.5%), improvement of symptoms (22.7%), and adverse reactions (14.5%). Children had higher adherence than adults (70.7% vs 55.0%) (p < 0.05). The dropout reasons were different among the children and adults groups (p < 0.005). The follow-up work was carefully and thoroughly done. All the 311 (100%) patients accepted the telephone interview, and 296 (95.2%) patients submitted questions and got rapid replies from doctors online. CONCLUSION Adherence to SCIT was less than satisfactory in the real-life study. A close communication between doctors and patients is helpful in enhancing adherence with AIT in clinical practice.

In this article, we consider and investigate the cases when the retailer's capitals are restricted and when the supplier offers another kind of 2-level trade credit. This means that the supplier offers 2-level trade credit for the retailer to settle the account and the retailer's capitals are restricted, so the retailer decides to pay off the unpaid balance as follows: Firstly, the retailer decides to pay off the unpaid balance at the end of the first credit period if the retailer can pay off all accounts and, in addition, the retailer can use the sales revenue to earn interest throughout the replenishment cycle time. Secondly, the retailer decides to pay off all accounts either after the end of the first credit period, but before the second credit period, or after the second credit period if the retailer cannot pay off the unpaid balance at the end of the first credit period. Additionally, the delay will incur interest charges on the unpaid and overdue balance due to the difference between the interest earned and the interest charged. Consequently, the main purpose of this article is to characterize the optimal solution processes and (in accordance with the functional behavior of the cost function) to search for the optimal replenishment cycle time. Finally, numerical examples are given to illustrate the theoretical results which are proven in this article by means of mathematical solution procedures.

Efficient production is essential for developing baculoviruses into marketable bioinsecticides. In this study, we evaluated how juvenile hormone (JH) III and the JH analog pyriproxyfen affected the production efficiency of Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) Nucleopolyhedrovirus (SpltNPV) in SpltNPV-inoculated early sixth instars. Both the JH III and pyriproxyfen treatments significantly enhanced the body size and weight of S. litura, which resulted in a 1.5- to 2-fold increase in the production of occlusion bodies (OBs). The OBs obtained from JH- and pyriproxyfen-treated larvae were as pathogenic as those produced in untreated larvae. More importantly, JH- or pyriproxy-fen-treated larvae consumed less than twice the amount of food consumed by two untreated larvae. These results indicate that JH and pyriproxyfen treatments improve the production efficiency of SpltNPV in S. litura. SpltNPV infection affected the development of S. litura not only as larvae, but also during subsequent growth stages and generations.

AIM Longitudinal data of the reactivation of hepatitis B virus (rHBV) and serial serological markers or HBV-DNA has been limited. This study aimed to investigate the temporal course of rHBV development in rheumatoid arthritis (RA) patients undergoing long-term rituximab therapy. METHODS The occurrence of rHBV was examined in 157 RA patients during rituximab therapy. Serum levels of HBV surface antigen (HBsAg), HBV core antibody (HBcAb), and HBsAb were determined by electrochemiluminescence immunoassays, and viral loads by real-time polymerase chain reaction assay. RESULTS Among 157 patients undergoing rituximab therapy, 103 (65.6%) were HBsAg-negative and HBcAb-positive. Before rituximab therapy, 20 (19.4%) of these 103 patients were HBsAb-negative, while 83 (80.1%) were HBsAb-positive. Five (20%) HBsAb-negative patients developed rHBV after rituximab therapy. Among 83 HBsAb-positive patients, 4 (4.8%) developed rHBV. Among 9 patients with rHBV, 7 (77.7%) exhibited HBsAg seroreversion. Significant decline of HBsAb titers (mean ± SD, 296.0 ± 417.3 mIU/mL at baseline vs 187.0 ± 332.5 mIU/mL after rituximab therapy, P

Direct mass-transfer via liquid nanodroplets is one of the most powerful approaches for additive micro/nanofabrication. Electrohydrodynamic (EHD) dispensing has made the delivery of nanosized droplets containing diverse materials a practical reality; however, in its serial form it has insufficient throughput for large-area processing. Here, a parallel, nanoscale EHD method is developed that offers both improved productivity and material diversity in 3D nanoprinting. The method exploits a double-barreled glass nanopipette filled with material inks to parallelize nanodripping ejections, enabling a dual 3D nanoprinting process. It is discovered that an unusual electric field distribution created by cross talk of neighboring pipette apertures can be used to steer the microscopic ejection paths of the ink at will, enabling on-demand control over shape, placement, and material mixing in 3D printed nanostructures. After thorough characterizations of the printing conditions, the parallel fabrication of nanomeshes and nanowalls of silver, CdSe/ZnS quantum dots, and their composites, with programmed designs is demonstrated. This method is expected to advance productivity in the heterogeneous integration of functional 3D nanodevices in a facile manner.

T-Brain-1 (TBR1), a causative gene in autism spectrum disorders (ASDs), encodes a brain-specific T-box transcription factor. It is therefore possible that TBR1 controls the expression of other autism risk factors. The downstream genes of TBR1 have been identified using microarray and promoter analyses. In this study, we annotated individual genes downstream of TBR1 and investigated any associations with ASDs through extensive literature searches. Of 124 TBR1 target genes, 23 were reported to be associated with ASDs. In addition, one gene, Kiaa0319, is a known causative gene for dyslexia, a disorder frequently associated with autism. A change in expression level in 10 of these 24 genes has been previously confirmed. We further validated the alteration of RNA expression levels of Kiaa0319, Baiap2, and Gad1 in Tbr1 deficient mice. Among these 24 genes, four transcription factors Auts2, Nfia, Nr4a2, and Sox5 were found, suggesting that TBR1 controls a transcriptional cascade relevant to autism pathogenesis. A further five of the 24 genes (Cd44, Cdh8, Cntn6, Gpc6, and Ntng1) encode membrane proteins that regulate cell adhesion and axonal outgrowth. These genes likely contribute to the role of TBR1 in regulation of neuronal migration and axonal extension. Besides, decreases in Grin2b expression and increases in Gad1 expression imply that neuronal activity may be aberrant in Tbr1 deficient mice. These analyses provide direction for future experiments to reveal the pathogenic mechanism of autism. Autism Res 2015, 8: 412–426. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.

Coronary artery disease is a great threat to human health and is the leading killer worldwide. Percutaneous coronary intervention is the most effective therapy; however, thrombus, and restenosis caused by endothelium injury continue to be problematic after treatment. It is widely accepted that surface biofunctional modification to improve blood compatibility and accelerate endothelialization may be an effective approach to prevent the occurrence of adverse cardiac events. In this study, novel VEGF-loaded heparin/poly-l-lysine (Hep/PLL) particles were developed and immobilized on a dopamine coated titanium surface. The size, distribution, zeta potential, and morphology of the prepared particles were subsequently characterized. The influence of changes in the surface physicochemical properties after particle immobilization was assessed for blood compatibility and cytocompatibility. Surface-modified VEGF-loaded particles significantly inhibited platelet adhesion and activation and were effective in promoting the proliferation and survival of endothelial progenitor cells and endothelial cells. Moreover, Hep/PLL particles were also beneficial for controlling the long-term release of VEGF, which may facilitate endothelium regeneration. In conclusion, VEGF-loaded Hep/PLL particles were successfully immobilized on the Ti surface, and the biocompatibility was significantly improved. This study demonstrates a potential application for the multifunctional modification of stent surfaces for clinical use. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 2024–2034, 2015.

Nitric oxide (NO) is a signaling molecule that plays a pivotal role in the diagnosis, treatment, and prevention of life threatening cardiovascular disorders. In this work, a facile method to construct catalytic coating with controlled NO release properties has been developed. The process involves in the first-step the deposition of plasma polymerized allylamine coating to introduce amine groups onto the titanium foils, followed by covalently immobilizing 3,3-diselenodipropionic acid (SeDPA), which is an organoselenium compound mimicking glutathione peroxidase-like catalytic production of NO. The NO release correlated positively with the –Se–Se– content in the functionalized film. After 15 d exposure to an NO donor, the –Se–Se– group was well retained with good biostability and ability of NO generation.

Tremendous demands for highly sensitive and selective nonenzymatic electrochemical biosensors have motivated intensive research on advanced electrode materials with high electrocatalytic activity. Herein, the 3D-networked CuO@carbon nanowalls/diamond (C/D) architecture is rationally designed, and it demonstrates wide linear range (0.5 × 10-6 -4 × 10-3 m), high sensitivity (1650 µA cm-2 mm-1 ), and low detection limit (0.5 × 10-6 m), together with high selectivity, great long-term stability, and good reproducibility in glucose determination. The outstanding performance of the CuO@C/D electrode can be ascribed to the synergistic effect coming from high-electrocatalytic-activity CuO nanoparticles and 3D-networked conductive C/D film. The C/D film is composed of carbon nanowalls and diamond nanoplatelets; and owing to the large surface area, accessible open surfaces, and high electrical conduction, it works as an excellent transducer, greatly accelerating the mass- and charge-transport kinetics of electrocatalytic reaction on the CuO biorecognition element. Besides, the vertical aligned diamond nanoplatelet scaffolds could improve structural and mechanical stability of the designed electrode in long-term performance. The excellent CuO@C/D electrode promises potential application in practical glucose detection, and the strategy proposed here can also be extended to construct other biorecognition elements on the 3D-networked conductive C/D transducer for various high-performance nonenzymatic electrochemical biosensors.

Restenosis and thrombosis formation after cardiovascular devices implantation continue to be problematic. Although various platforms and parameters of cardiovascular devices have been designed and optimized over the years, postoperative complications are hard to avoid. The native vascular endothelium always provide a nonthrombogenic surface as well as prevent intimal overproliferation, thereby, the presence of a confluent endothelial cell layer on material surfaces have been widely accepted as an ideal approach to improve the biocompatibility of implanted cardiovascular materials. Endothelialization on biomaterial surfaces is initially developed by in vitro cell seeding. However, numerous no-perfect parts of this method are existed for clinical use. The emergency of endothelial progenitor cells may provide a promising way for setting these limitations. Over the last decades, countless researches about EPCs-based in vivo induced self-endothelialization have been reported and mainly focused on cellular therapy, pharmacological therapy, materials designing, or surface biofunctional modification. This review details the development of endothelialization on cardiovascular material surfaces from in vitro to in vivo. Endothelialization progress on the basis of molecular biological level and bioinformatics theory is expected to be the key point in the coming decades.

Driven by the complications occurring with bare metal stents and drug-eluting stents, concerns have been raised over strategies for long-term safety, with respect to preventing or inhibiting stent thrombosis, restenosis, and in-stent restenosis in particularly. Surface modification is very important in constructing a buffer layer at the interface of the organic and inorganic materials and in ultimately obtaining long-term biocompatibility. In this review, we summarize the developments in surface modification of implanted cardiovascular metal stents. This review focuses on the modification of metal stents via coating drugs or biomolecules to enhance antithrombosis, antirestenosis, and/or endothelialization. In addition, we indicate the probable future work involving the modification of the metallic blood-contacting surfaces of stents and other cardiovascular devices that are under development.

Orientation smooth muscle cell environment plays a positive role in the development of a functional, adherent endothelium. Therefore, building an orientation coculture model of endothelial cells (ECs) and smooth muscle cells (SMCs) on biomaterials surface may provide more help for understanding the interaction between the two cells in vitro. In the present study, a "SMCs-ColIV-ECs" coculture model was built on the hyaluronic acid (HA) patterned titanium (Ti) surface, and compared with the previous "SMCs-HAa-ECs" model on endothelial cell number, morphology index, nitric oxide (NO), and prostacyclin2 (PGI2) release, anticoagulation property, human umbilical artery smooth muscle cells (HUASMCs) inhibition property and retention under fluid flow shear stress. The result indicated that "SMCs-ColIV-ECs" model could enhance the number, spreading area, and major/minor index of human umbilical vein endothelial cells (HUVECs), which contributed to the retention of HUVECs on the surface. Greater major/minor index may produce more NO and PGI2 release, contributing to the anticoagulation property and HUASMCs inhibition property. In summary, this novel "SMCs-ColIV-ECs" coculture model improved the previous "SMCs-HAa-ECs" model, and may provide more inspiration for the human vascular intima building on the biomaterials in vitro.

BACKGROUND Repellents are a common method for preventing flea bites, making an effective system for flea repellent screening advantageous. We describe an improved technique to facilitate repellent activity screening of numerous plant-based Ctenocephalides felis (cat flea) repellents. RESULTS Two long strips of filter paper were impregnated with test compounds (dissolved in ethanol) and ethanol only, respectively. After drying, the two filter papers were glued together along the long side and inserted into a glass tube containing non-fed cat fleas. The distribution of cat fleas in each half of the filter paper was recorded after 30 min to calculate repellency. Results showed that the essential oil of Cinnamomum osmophloeum (from leaf), Taiwania cryptomerioides (from heartwood) and Plectranthus amboinicus (from leaf) exhibits repellent activity against cat fleas in a dose dependent manner. Moreover, the repellent activities against cat fleas of 2% trans-cinnamaldehyde (the main constituent of Ci. osmophloeum essential oil) and 0.5% thymol (the main constituent of P. amboinicus essential oil) are 97.6% and 90.6%, and can persist for up to 4 and 8 h, respectively. These results are comparable to those of 15% DEET. CONCLUSION The proposed screening technique can facilitate the pre-screening of numerous flea repellents for further evaluation on animal or human subjects. © 2013 Society of Chemical Industry

In an attempt to link the microbial community composition and function in mine tailings to the generation of acid mine drainage, we simultaneously explored the geochemistry and microbiology of six tailings collected from a lead/zinc mine, i.e. primary tailings (T1), slightly acidic tailings (T2), extremely acidic tailings (T3, T4 and T5) and orange-coloured oxidized tailings (T6). Geochemical results showed that the six tailings (from T1 to T6) likely represented sequential stages of the acidification process of the mine tailings. 16S rRNA pyrosequencing revealed a contrasting microbial composition between the six tailings: Proteobacteria-related sequences dominated T1-T3 with relative abundance ranging from 56 to 93%, whereas Ferroplasma-related sequences dominated T4-T6 with relative abundance ranging from 28 to 58%. Furthermore, metagenomic analysis of the microbial communities of T2 and T6 indicated that the genes encoding key enzymes for microbial carbon fixation, nitrogen fixation and sulfur oxidation in T2 were largely from Thiobacillus and Acidithiobacillus, Methylococcus capsulatus, and Thiobacillus denitrificans respectively; while those in T6 were mostly identified in Acidithiobacillus and Leptospirillum, Acidithiobacillus and Leptospirillum, and Acidithiobacillus respectively. The microbial communities in T2 and T6 harboured more genes suggesting diverse metabolic capacities for sulfur oxidation/heavy metal detoxification and tolerating low pH respectively.