Efficacy of relacin combined with sodium hypochlorite against Enterococcus faecalis biofilms

Objective: Relacin is a synthetic molecule that targets RelA, an essential protein in a conserved bacterial stress response system. It was shown to inhibit bacterial growth. The aims of this study were to evaluate the antimicrobial effect of relacin combined with sodium hypochlorite (NaOCl) on Enterococcus faecalis biofilms and to evaluate the cytotoxicity of relacin. Material and Methods: 48-h E. faecalis OG1RF biofilms were treated by various concentrations of relacin in order to determine its inhibitory concentration. Then, the 48-h biofilms were treated either with 1-min NaOCl (0.01%, 0.05%) alone, or in combination of relacin. As a means of comparison, the biofilms of ΔrelA were also treated by 1-min NaOCl (0.01%, 0.05%, 0.25%). The treatment efficacy was determined by agar plate count assays. The cytotoxicity of relacin was examined on human gingival epithelial cells Ca9-22 and murine fibroblasts NIH-3T3 by a methyl thiazolyltetrazolium (MTT) assay and a lactate dehydrogenase assay. Statistical analysis was performed by one-way or two-way analysis of variance (ANOVA) with Bonferroni’s post-hoc test and an independent Student’s t-test. A significance level of p<0.05 was used. Results: Relacin inhibited the growth of OG1RF biofilms partially at 8 mM and fully at 14 mM. The relacin (14 mM) and NaOCl combined treatment resulted in significantly higher treatment efficacy than NaOCl treatment alone. At 0.05% NaOCl, the combined treatment resulted in 5.65 (±0.19) log reduction in biofilm viability. The ΔrelA biofilms were more susceptible to NaOCl treatment than the wild type biofilms at 0.25% NaOCl. Relacin at 14 mM was not toxic to host epithelial cells and fibroblasts. Conclusions: The combination of relacin with a low concentration of NaOCl was effective and not cytotoxic

TJECAJ FLUKTUACIJE CIJENA NA EFIKASNOST RASPODJELE RESURSA

This paper develops a dynamic model to analyze the effects of different levels of price fluctuations on resource allocation efficiency. The model shows two different strategies that enterprises adopt when they confront different levels of price fluctuations. In respond to small fluctuations, enterprises might adopt a conservative strategy of maintaining the ratio of factor inputs and leaving production plans unchanged of the adjustment cost. As a result, allocation inefficiency is unavoidable. However, greater fluctuations which increase the opportunity cost of a conservative strategy induce enterprises to accept an adjustment strategy; they must change the ratio of factor inputs and the production plans passively. This transformation indicates that a threshold effect exists in the price fluctuations’ influence on resource allocation inefficiency. Using stochastic frontier analysis (SFA) and China’s provincial panel data of 1978 to 2007, this paper confirms that price fluctuation has a nonlinear effect on allocation efficiency loss, and concludes that traditional analyses underestimate the adverse impacts of price fluctuation on China\u27s economy.Ovaj rad razvija dinamički model za analizu efekata različitih nivoa fluktuacija cijena na efikasnost raspodjele resursa. Model pokazuje dvije različite strategije koje poduzeća usvajaju pri suočavanju s različitim nivoima fluktuacije cijena. Kao odgovor malim fluktuacijama, poduzeća bi mogla usvojiti konzervativnu strategiju održavanja omjera faktorskih troškova i ostavljanja proizvodnih planova nepromijenjenim za troškove prilagodbe. Na taj način je neefikasnost raspodjele neizbježna. Ipak, veće fluktuacije koje povećavaju mogućnost troška konzervativne strategije prisiljavaju poduzeća da prihvate strategiju prilagođavanja; moraju pasivno promijeniti omjer faktorskih troškova i planova proizvodnje. Ova transformacija ukazuje na to da postoji efekt praga kod utjecaja fluktuacije cijena na neefikasnost raspodjele resursa. Koristeći analizu stohastičkih granica (SFA) i kineske provincijske panelne podatke od 1978. do 2007., ovaj rad potvrđuje da fluktuacija cijena ima nelinearni efekt na gubitak efikasnosti raspodjele te zaključuje da tradicionalne analize podcjenjuju negativne utjecaje fluktuacije cijena na kinesku ekonomiju

Enterococcus faecalis Immunoregulates Osteoclastogenesis of Macrophages

published_or_final_versio

Application of a Novel Semiconductor Catalyst, CT, in Degradation of Aromatic Pollutants in Wastewater: Phenol and Catechol

Water-soluble phenol and phenolic compounds were generally removed via advanced oxidation processes. A novel semiconductor catalyst, CT, was the first-time employed in the present study to degrade phenol and catechol. The phenolic compounds (initial concentration of 88 mg L−1) were completely mineralized by the CT catalytic nanoparticles (1%) within 15 days, under acidic condition and with the presence of mild UV radiation (15 w, the emitted wavelength is 254 nm and the light intensity <26 μw/cm2). Under the same reaction condition, 1% TiO2 (mixture of rutile and anatase, nanopowder, <100 nm) and H2O2 had lower removal efficiency (phenol: <42%; catechol: <60%), whereas the control (without addition of catalysts/H2O2) only showed <12% removal. The processes of phenol/catechol removal by CT followed pseudo-zero-order kinetics. The aromatic structures absorbed the UV energy and passed to an excited state, which the CT worked on. The pollutants were adsorbed on the CT’s surface and oxidized via charge-transfer and hydroxyl radical generation by CT. Given low initial concentrations, a circumstance encountered in wastewater polishing, the current set-up should be an efficient and less energy- and chemical-consumptive treatment method

The Genomes of Oryza sativa: A History of Duplications

We report improved whole-genome shotgun sequences for the genomes of indica and japonica rice, both with multimegabase contiguity, or almost 1,000-fold improvement over the drafts of 2002. Tested against a nonredundant collection of 19,079 full-length cDNAs, 97.7% of the genes are aligned, without fragmentation, to the mapped super-scaffolds of one or the other genome. We introduce a gene identification procedure for plants that does not rely on similarity to known genes to remove erroneous predictions resulting from transposable elements. Using the available EST data to adjust for residual errors in the predictions, the estimated gene count is at least 38,000–40,000. Only 2%–3% of the genes are unique to any one subspecies, comparable to the amount of sequence that might still be missing. Despite this lack of variation in gene content, there is enormous variation in the intergenic regions. At least a quarter of the two sequences could not be aligned, and where they could be aligned, single nucleotide polymorphism (SNP) rates varied from as little as 3.0 SNP/kb in the coding regions to 27.6 SNP/kb in the transposable elements. A more inclusive new approach for analyzing duplication history is introduced here. It reveals an ancient whole-genome duplication, a recent segmental duplication on Chromosomes 11 and 12, and massive ongoing individual gene duplications. We find 18 distinct pairs of duplicated segments that cover 65.7% of the genome; 17 of these pairs date back to a common time before the divergence of the grasses. More important, ongoing individual gene duplications provide a never-ending source of raw material for gene genesis and are major contributors to the differences between members of the grass family

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals &lt;1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Single-step Transepithelial photorefractive keratectomy in the treatment of mild, moderate, and high myopia: six month results

Abstract Background To evaluate the safety, efficacy, and the refractive outcomes of single-step transepithelial photorefractive keratectomy (TransPRK) for the correction of mild, moderate, and high myopia. Methods This study consecutively recruited 32 high myopic eyes, 32 mild myopic and 32 moderate myopic eyes. Eyes with myopia that had undergone TransPRK treatment. Pre- and post-operative visual and refractive data, corneal Higher Order Aberration (HOA) as well as safety and efficacy indices were analyzed at 6 months postoperatively. Results Six months after TransPRK, the manifest refraction spherical equivalent (SE) was not significantly between high myopia group and moderate myopia group (p = 0.636). No eyes lost ≥2 lines of corrected distant visual acuity (CDVA) in high myopic eyes. The uncorrected distance visual acuity (UDVA) was significantly higher in low and moderate myopia groups than the high myopia group (P 0.05). The mean safety index was significantly higher in the moderate myopia group (1.16 ± 0.23) than in the high myopia group (1.01 ± 0.14) (P = 0.002). The efficacy index was significantly higher in the moderate myopia group (1.05 ± 0.20) than in the high myopia group (0.89 ± 0.17) (P = 0.02), and there was no significant difference between the high myopia group (0.89 ± 0.17) and the low myopia group (0.96 ± 0.16) (P = 0.14). Conclusions The mean safety index was over 1.0 in the three groups. TransPRK showed acceptable safety and efficacy in the moderate myopic eyes, as well as mild and high myopic eyes. High myopic eyes got very similar refractive results with moderate myopic eyes six months postoperatively. The safety and efficacy indexes were not significantly different between the high myopia group and the low myopia group

Clinical outcomes of Transepithelial photorefractive keratectomy to treat low to moderate myopic astigmatism

Abstract Background To evaluate the refractive and visual outcomes of Transepithelial photorefractive keratectomy (TransPRK) in the treatment of low to moderate myopic astigmatism. Methods This retrospective study enrolled a total of 47 eyes that had undergone Transepithelial photorefractive keratectomy. Preoperative cylinder diopters ranged from − 0.75D to − 2.25D (mean − 1.11 ± 0.40D), and the sphere was between − 1.50D to − 5.75D. Visual outcomes and vector analysis of astigmatism that included error ratio (ER), correction ratio (CR), error of magnitude (EM) and error of angle (EA) were evaluated. Results At 6 months after TransPRK, all eyes had an uncorrected distance visual acuity of 20/20 or better, no eyes lost ≥2 lines of corrected distant visual acuity (CDVA), and 93.6% had residual refractive cylinder within ±0.50D of intended correction. On vector analysis, the mean correction ratio for refractive cylinder was 1.03 ± 0.30. The mean error magnitude was − 0.04 ± 0.36. The mean error of angle was 0.44° ± 7.42°and 80.9% of eyes had axis shift within ±10°. The absolute astigmatic error of magnitude was statistically significantly correlated with the intended cylinder correction (r = 0.48, P < 0.01). Conclusions TransPRK showed safe, effective and predictable results in the correction of low to moderate astigmatism and myopia