The Emerging Regulatory Role of Circular RNAs in Periodontal Tissues and Cells

Periodontitis is a chronic complex inflammatory disease associated with a destructive host immune response to microbial dysbiosis, leading to irreversible loss of tooth-supporting tissues. Regeneration of functional periodontal soft (periodontal ligament and gingiva) and hard tissue components (cementum and alveolar bone) to replace lost tissues is the ultimate goal of periodontal treatment, but clinically predictable treatments are lacking. Similarly, the identification of biomarkers that can be used to accurately diagnose periodontitis activity is lacking. A relatively novel category of molecules found in oral tissue, circular RNAs (circRNAs) are single-stranded endogenous, long, non-coding RNA molecules, with covalently circular-closed structures without a 5’ cap and a 3’ tail via non-classic backsplicing. Emerging research indicates that circRNAs are tissue and disease-specific expressed and have crucial regulatory functions in various diseases. CircRNAs can function as microRNA or RNA binding sites or can regulate mRNA. In this review, we explore the biogenesis and function of circRNAs in the context of the emerging role of circRNAs in periodontitis pathogenesis and the differentiation of periodontal cells. CircMAP3K11, circCDK8, circCDR1as, circ_0062491, and circ_0095812 are associated with pathological periodontitis tissues. Furthermore, circRNAs are expressed in periodontal cells in a cell-specific manner. They can function as microRNA sponges and can form circRNA–miRNA–mRNA networks during osteogenic differentiation for periodontal-tissue (or dental pulp)-derived progenitor cells.     

Urban livability in socially disadvantaged neighborhoods: The experience of the German program “socially integrative city”

This paper asks how the livability of socially disadvantaged urban neighborhoods can be improved with the help of publicly funded area-based urban regeneration. It builds on the history of area-based regeneration policies in Germany aiming at upgrading and resolving urban problems at the neighborhood level. Its main argument is as follows. First, the fate of conventional physical upgrading policies focusing on the livability of deprived urban areas depends on the development environment. While successful upgrading sometimes makes inner-city neighborhoods so attractive that they run into a trend towards gentrification and displacement of the urban poor, the stabilization of less privileged areas cannot always be guaranteed. Second, alternative approaches are needed, linking limited physical upgrading with socially oriented policies, building on strategies like neighborhood management and empowerment. Third, they can make a substantial contribution to stabilizing deprived neighborhoods, thereby improving the general living conditions and the opportunities of the urban poor. However, they require at least some permanent intervention. Thus, they transcend the logic of area-based regeneration normally limited to restoring faith into the private real estate market and thereby directing inward investment into them that improves the quality of the physical environment. Fourth, they are hardly able to overcome significant negative stigmatization in cities that are severely hit by economic downturn and population decline. This is especially true when they act as arrival areas for consecutive waves of migrants, making it necessary to redefine the role of those areas in cities and accepting their high concentration of urban problems as a starting point for different area-based policies dealing with them. The key empirical background of the paper is the German system of urban development grants and an evaluation of the so-called program of “socially integrative city”.     

ZnO·2.7Al2O3 nanocomposite with high optical transparency

Here we report a transparent dual-phase ZnO·2.7Al₂O₃ ceramic. The composite is pore-free and consists of thin nanosheets with a spinel phase and a hexagonal phase, while the two phases match closely in both lattice and refractive index. Such features result in excellent optical transmittance (maximum value >80% in the visible spectrum) at comparable phase volume. This work may provide a new thought for the rational structural design of optical nanocomposites.     

Experimental study on mitigating wind erosion of calcareous desert sand using spray method for microbially induced calcium carbonate precipitation

Wind erosion is one of the significant natural calamities worldwide, which degrades around one-third of global land. The eroded and suspended soil particles in the environment may cause health hazards, i.e. allergies and respiratory diseases, due to the presence of harmful contaminants, bacteria, and pollens. The present study evaluates the feasibility of microbially induced calcium carbonate precipitation (MICP) technique to mitigate wind-induced erosion of calcareous desert sand (Thar desert of Rajasthan province in India). The temperature during biotreatment was kept at 36 °C to stimulate the average temperature of the Thar desert. The spray method was used for bioaugmentation of Sporosarcina (S.) pasteurii and further treatment using chemical solutions. The chemical solution of 0.25 pore volume was sprayed continuously up to 5 d, 10 d, 15 d, and 20 d, using two different concentration ratios of urea and calcium chloride dihydrate viz 2:1 and 1:1. The biotreated samples were subjected to erosion testing (in the wind tunnel) at different wind speeds of 10 m/s, 20 m/s, and 30 m/s. The unconfined compressive strength of the biocemented crust was measured using a pocket penetrometer. The variation in calcite precipitation and microstructure (including the presence of crystalline minerals) of untreated as well as biotreated sand samples were determined through calcimeter, scanning electron microscope (SEM), and energy-dispersive X-ray spectroscope (EDX). The results demonstrated that the erosion of untreated sand increases with an increase in wind speeds. When compared to untreated sand, a lower erosion was observed in all biocemented sand samples, irrespective of treatment condition and wind speed. It was observed that the sample treated with 1:1 cementation solution for up to 5 d, was found to effectively resist erosion at a wind speed of 10 m/s. Moreover, a significant erosion resistance was ascertained in 15 d and 20 d treated samples at higher wind speeds. The calcite content percentage, thickness of crust, bulk density, and surface strength of biocemented sand were enhanced with the increase in treatment duration. The 1:1 concentration ratio of cementation solution was found effective in improving crust thickness and surface strength as compared to 2:1 concentration ratio of cementation solution. The calcite crystals formation was observed in SEM analysis and calcium peaks were observed in EDX analysis for biotreated sand.     

Model of reactive precipitation process of preparation nano-ZnO in rotating packed bed: Contribution ratio

With excellent micromixing characteristic of rotating packed bed (RPB), many nanoparticles with small average size, narrower distribution and good morphology had been successfully and continuously prepared. To reveal complex crystal process, an empirical model were developed to simulate nano-ZnO by considering mass changed, population balance equation, growth rate G, nucleation rate B, drop sizes D_i, and resident time t. The predicted particle sizes were shown good agreement with experimental data with error of ±10%. Therefore, it was further adopted to predict the effects of rotating speed, liquid flow rate and reactant concentration on the mean particle size. To look more deeply insight in this process, their contribution ratios were further analyzed. The proposed empirical models were of great helpful to obtain suitable operation conditions for preparing much better properties of nanoparticles with fewer experiments. It was also beneficial to produce other nanoparticles in RPB.     

基于三种干旱指标的朝阳市干旱特征分析

旱灾具有出现频率高、持续时间长、波及范围广等特点，本文运用降水距平百分率、Z指数、SPI标准化降水指数，对朝阳地区50a（1969～2018）干旱特征进行分析。结果表明：Z指数与SPI标准化降水指标得到的朝阳地区干旱特征情况基本一致，能较好地反映出该地区的干旱特征，朝阳地区1969～2018年自然灾害频繁发生，严重干旱年份主要集中在1980、1981、1982 年，与实际相符。     

Granulation Tissue Enhanced with Aspirin and Omega-3 PUFAs as a Local Adjunct to the Surgical Treatment of Periodontitis

The topical application of aspirin and omega-3 polyunsaturated fatty acids (PUFAs) may trigger the resolution of inflammation by inducing the biosynthesis of pro-resolvers such as lipoxins and resolvins while also avoiding the side effects of systemic aspirin intake. This study assessed the effect of enhanced granulation tissue (EGT) on periodontal tissue regeneration through the local application of aspirin and omega-3 PUFAs directly to granulation tissue (GT) during periodontal surgery. This randomized controlled experiment assesses 38 pockets in 19 patients. In every patient, two similar intrabony periodontal defects are treated with an open flap debridement, one with EGT (GT extracted, enhanced with aspirin and omega-3 PUFAs, and replaced) and the other with standard GT removal. Clinical attachment level (CAL) and probing pocket depth (PPD) are assessed at baseline and 2 and 6 months after surgery. The experimental protocol (EGT) results in a greater CAL gain as compared to that in the controls at 6 months (p < 0.05), while PPD reduction is not affected. The retained GT does not compromise healing. EGT is proposed as a promising, inexpensive, and simple method that may improve the outcome of periodontal regenerative treatment. However, the described protocol requires optimization and further assessment. Practical Applications : The biosynthesis of mediators including resolvins and lipoxins triggered by aspirin and omega-3 PUFAs promote the resolution of inflammation, eventually leading to faster regeneration of inflamed tissues. While granulation tissue is a necessary component in wound healing, enhancing granulation tissue with aspirin and omega-3 PUFAs results in CAL gain in the surgical treatment of periodontal defects. Retained granulation tissue does not compromise periodontal healing. The EGT strategy is an inexpensive and simple method that may improve the clinical outcomes of regenerative periodontal procedures.     

混菌矿化增强再生粗骨料的物理力学性能

为克服单一微生物培养成本高且矿化鲁棒性不足的缺陷，提出了一种混菌矿化增强再生粗骨料物理力学性能的方法.通过筛选矿化效率较高的好氧嗜碱混菌，考察了混菌矿化对再生粗骨料物理力学性能和混凝土抗压强度的影响.结果表明：相同增强时间下，混菌比纯菌呈现出更优异的矿化增强效果；随着混菌矿化增强时间的延长，再生粗骨料吸水率和压碎指标呈现出先减小后增大的趋势，最优增强时间为15 d；采用矿化增强再生粗骨料制备的再生混凝土抗压强度提高幅度达到22.1%.     

Production of the Carboxylate Reductase from Nocardia otitidiscaviarum in a Soluble,Active Form for in vitro Applications

Accessing aldehydes from carboxylate moieties is often a challenging task. In this regard, carboxylate reductases (CARs) are promising catalysts provided by nature that are able to accomplish this task in just one step, avoiding over-reduction to the alcohol product. However, the heterologous expression of CARs can be quite difficult due to the excessive formation of insoluble protein, thus hindering further characterization and application of the enzyme. Here, the heterologous production of the carboxylate reductase from Nocardia otitidiscaviarum (NoCAR) was optimized by a combination of i) optimized cultivation conditions, ii) post-translational modification with a phosphopantetheinyl transferase and iii) selection of an appropriate expression strain. Especially, the selection of Escherichia coli tuner cells as host had a strong effect on the final 110-fold increase in the specific activity of NoCAR. This highly active NoCAR was used to reduce sodium benzoate to benzaldehyde, and it was successfully assembled with an in vitro regeneration of ATP and NADPH, being capable of reducing about 30 mM sodium benzoate with high selectivity in only 2 h of reaction.     

Inorganic Nanoparticles Applied as Functional Therapeutics

Inorganic nanoparticles (NPs) offer significant advantages to the biomedical field owing to their large surface area, controllable structures, diverse surface chemistry, and unique optical and physical properties. Researchers worldwide have shown that inorganic NPs and the released metal ions can act as therapeutic agents in targeted tissues or to cure various diseases without acute toxicity. In this progress report, the recent developments in inorganic NPs with different compositions directly used as therapeutics are discussed. First, the recent convergence of nanotechnology and biotechnology in biomedical applications as well as the unique functions, features, and advantages of inorganic NPs in biomedical applications are summarized. Thereafter, the biological effects of inorganic compositions in NPs which include balancing the intracellular redox environment, regulating the specific cellular signaling and cellular behaviors, and apoptosis are explained. In addition, the emerging therapeutic applications of inorganic NPs in various diseases are exemplified. Finally, the perspectives and challenges for overcoming the weaknesses of inorganic NPs as therapeutics are discussed. By carefully considering and investigating the biological effects of inorganic NPs and metal ions released from NPs, more promising inorganic NPs based therapeutic agents can be developed.