Stimulation of human gingival fibroblasts viability and growth by roots treated with high intensity lasers,photodynamic therapy and citric acid

ObjectiveThe aim of this study was to compare the effect of root biomodification by lasers, citric acid and antimicrobial photodynamic therapy (aPDT) on viability and proliferation of human gingival fibroblasts (FGH).DesignGroups were divided in control (CC – only cells), and root fragments treated by: scaling and root planing (positice control – SC), Er:YAG (ER–60 mJ,10pps,10 Hz,10s,2940 nm), Nd:YAG (ND–0.5W,15 Hz,10s,1640 nm), antimicrobial photodynamic therapy (PDT–InGaAIP,30 mW,45J/cm²,30s,660 nm,toluidine blue O), citric acid plus tetracycline (CA). Fibroblasts (6th passage, 2 × 10³) were cultivated in a 24-h conditioned medium by the treated root fragments. Cell viability was measured by MTT test at 24, 48, 72 and 96 h. In a second experiment, FGH cells (10⁴) were cultivated on root fragments which received the same treatments. After 24, 48, 72 h the number of cells was counted in SEM pictures. In addition, chemical elements were analyzed by energy dispersive spectroscopy (EDS). Data was analyzed by two-way ANOVA (first experiment), repeated measures ANOVA (second experiment) and ANOVA (EDS experiment) tests complemented by Tukey’s test (p < 0.05).ResultsND, PDT and CA promoted higher cell viability (p < 0.05). ND and ER groups presented higher number of cells on root surfaces (p < 0.05). ER group presented higher calcium and CA group a higher carbon percentages (p < 0.05).ConclusionsAll treatments but scaling and root planing stimulated fibroblast viability while Er:YAG and Nd:YAG treated root surfaces presented higher number of cells.     

Nanospace-confined preparation of uniform nitrogen-doped graphene quantum dots for highly selective fluorescence dual-function determination of Fe3+ and ascorbic acid

N-Doped graphene quantum dots (N-GQDs) combine the advantages of N-doped carbon and quantum dot materials, displaying enhanced performance in electrocatalysis, drug delivery, sensing and so on. In this work, novel hydrotropic N-GQDs with controlled size are obtained for the first time via a nanospace-confined preparation strategy, in which HNO₃ vapour serves as scissors for quickly cutting the N-doped carbon nanolayer in the confined nanospace of reusable mesoporous molecular sieves. The as-prepared N-GQDs exhibit a uniform lateral size of about 2.4 nm, high photostability and yellow fluorescence, which is strongly quenched upon addition of ferric ions due to the coordination between ferric ions and N/O-rich groups of the N-GQDs surface. Significantly, the fluorescence response to Fe³⁺ is linear in the 0.5 to 40 μM concentration range and the N-GQDs showed good selectivity and satisfying recovery for ferric ion detection in tap water. Noteworthily, the quenched fluorescence by Fe³⁺ can be recovered by adding ascorbic acid (AA), which efficiently destroyed the coordination between Fe³⁺ and N-GQDs. Based on this principle, the N-GQDs were used to successfully construct an AA sensor, exhibiting a wide linearity range (between 0.5 and 90 μM) with a low detection of limit (80 nM at S/N = 3) and better selectivity towards AA compared with other common physiological substances. Finally, the constructed fluorescence sensor was employed successfully for AA determination in fish blood with satisfactory recovery ranging from 95.3 to 106.2%. The results indicate that N-GQDs synthesized by the nanospace-confined strategy are promising in biosensor fabrication.

Nanospace-confined synthesis of N-GQDs was successfully achieved via a mesoporous silica recycling and vapor cutting route for label-free fluorescence dual-function detection of Fe³⁺ and AA.     

何首乌饮对大鼠睾丸间质细胞类固醇激素合成急性调节蛋白和细胞色素P450胆固醇侧链裂解酶蛋白表达的影响

目的探究何首乌饮影响大鼠睾丸间质(Leydig)细胞类固醇激素合成急性调节蛋白(St AR)和细胞色素P450胆固醇侧链裂解酶(P450scc)蛋白表达的变化。方法选用10~20 d的幼年雄性Wistar大鼠,分离、培养Leydig细胞,然后收集。采用氧化损伤的方法建立Leydig细胞衰老模型。实验分组:间质细胞衰老模型组,何首乌饮处理组,首乌丸处理组,正常组和何首乌饮对照组。结果衰老模型组Leydig细胞St AR和P450scc的免疫组织化学染色强度明显低于正常组和何首乌饮对照组(P0.01)。另一方面,何首乌饮和何首乌丸干预组St AR和P450scc的免疫组织化学染色强度明显高于衰老模型组(P0.05),何首乌饮组好于何首乌丸组。结论何首乌饮可提高睾丸Leydig细胞St AR和P450scc蛋白的表达,提高睾酮的合成能力,从而延缓Leydig细胞衰老。     

Properties and Hydration Mechanism of Soda Residue-Activated Ground Granulated Blast Furnace Slag Cementitious Materials

Soda residue (SR), an industrial solid waste, pollutes the environment due to its high alkalinity and chloride ion content. SR can be used as an alkali activator of ground granulated blast furnace slag (GGBFS). This study investigated the effects of four types of SR-activated GGBFS cementitious materials (pastes) with different mass ratios of SR to GGBFS (8:92, 16:84, 24:76, 34:68) on the physical properties, mechanical strength, and chloride binding capacity. The hydration mechanism of the pastes was also studied. Results showed that with the increasing addition of SR, the density of the pastes decreased, and more white aggregates of SR appeared causing the increase of water absorption and porosity of the pastes. The pastes with 16% SR addition had the maximum compressive strength (34.1 MPa, 28 d), so the optimum proportion of SR addition in the pastes was 16%. With the increases of SR addition, the amount of chloride element in the initial pastes increases. When the proportion of SR addition is 8%, the mass percentage of free chloride ion in the pastes at 28 d is 0.13%. The main hydration products of the pastes were C–S–H gels, ettringite, and Friedel’s salt, and the amount of ettringite varied with the amount of SR addition and curing time.     

#br# 中国北方汉语族群汉族成人的体型

目的 探讨我国境内汉语方言族群中甘肃、河北、河南、辽宁和陕西5省汉族成人的体型特征及不同汉语方言区汉族成人的体型差异。方法 按照人体测量方法,测量来自甘肃、河北、河南、辽宁和陕西5省共计6201名（男3075名,女3126名）调查对象的身高、体重、小腿围等10项指标,并应用Heath-Carter体型评价法进行体型判定。 结果 甘肃省、河北省男性体型以偏内胚层的中胚层型为主,河南省、陕西省男性的体型以偏中胚层的内胚层型为主,辽宁省男性以内胚层 中胚层均衡型为主;5省汉族女性的体型均以偏中胚层的内胚层型为主。 结论 北方汉语方言族群汉族成人具有北亚类型族群的体质特征,北方汉语方言区的3个次方言区的汉族群体已呈现出一定的体型差异,但不同区域的汉族群体仍存在一定的亲缘关系。     

Effects of acute,intermittent exercise in hypoxic environments on the release of cardiac troponin

The purpose of this study was to examine the effects of acute, intermittent exercise performed in hypoxic environments on the release of cardiac troponin (cTn). Ten well‐trained, male marathon runners (22.1 ± 2.6 years, 64.0 ± 4.9 kg and 177.3 ± 3.9 cm) completed three intermittent exercise protocols under normoxic (trial N) and hypoxic (trial AH and RH) conditions. In trial N, the fraction of inspiration oxygen (FIO₂) was 21.0% and exercise intensity was 90% and 50% normoxic velocity of VO_2max (vVO_2max). In trial AH, FIO₂ was 14.4% (simulated altitude of 3000 m) and exercise intensity was 90% and 50% normoxic vVO_2max. In trial RH, FIO₂ was 14.4% and exercise intensity was 90% and 50% hypoxic vVO_2max. High‐sensitivity cardiac troponin T (hs‐cTnT) and cardiac troponin I (cTnI) were measured pre‐ and 0, 2, 4, and 24 h post‐exercise. Hs‐cTnT was elevated in all three trials, peaking at 2 to 4 h and returning to the baseline 24 h post‐exercise. CTnI increased in trial AH, peaking at 2 to 4 h and returning below the detection limit 24 h post‐exercise. It is concluded that the stimulus of hypoxia did not in and of itself induce more cTn to be released, but exercise intensity could affect this response in hypoxic environments.     

Performance Optimization and Characterization of Soda Residue-Fly Ash Geopolymer Paste for Goaf Backfill: Beta-Hemihydrate Gypsum Alternative to Sodium Silicate

Solid waste soda residue (SR), as an industrial pollutant of water, air and soil environment, can be utilized to prepare the low-calcium fly ash (FFA)-based geopolymer paste activated by sodium silicate (NS) solution for goaf backfill. However, the high addition of NS produces the high cost and high strength of synthesized backfill material in the previous study. The objective of this research is to investigate the cost optimization method and performance evaluation of SR-FFA-based geopolymer backfill paste. The alkaline beta-hemihydrate gypsum (BHG) alternative to partial NS was proposed. Scanning electron microscopy (SEM), X-ray diffraction (XRD) as well as Fourier transform infrared spectrometer (FTIR) tests were performed to clarify the role of BHG and evaluate the microstructures and products of backfill pastes. The results show that 10% BHG alternative ratios effectively improve fluidity, setting time and compressive strength to satisfy the performance requirement of goaf backfill material. The gel products in the optimal backfill paste C4 with 10% BHG alternative ratios are determined as the coexistence of C-S-H gel, (N,C)-A-S-H gel and CaSO₄·2H₂O at 28 d. The research results can make extensive utilization of SR and FFA in cemented paste backfill to synthesize cleaner material at a larger scale.     

Resistance of Soda Residue–Fly Ash Based Geopolymer Mortar to Acid and Sulfate Environments

The early mechanical performances of low-calcium fly ash (FFA)-based geopolymer (FFA–GEO) mortar can be enhanced by soda residue (SR). However, the resistance of SR–FFA–GEO mortar to acid or sulfate environments is unclear, owing to the various inorganic calcium salts in SR. The aim of this study was to investigate the long-term mechanical strengths of up to 360 d and evaluate the resistance of SR–FFA–GEO mortar to 5% HCl and 5% Na₂SO₄ environments through the losses in compressive strength and mass. Scanning Electron Microscopy (SEM), Energy-Dispersive Spectroscopy (EDS) and Fourier Transform Infrared Spectrometer (FTIR) experiments were conducted for the SR–FFA–GEO mortars, both before and after chemical attack, to clarify the attack mechanism. The results show that the resistances of the SR–FFA–GEO mortar with 20% SR (namely M10) to 5% HCl and 5% Na₂SO₄ environments are superior to those of cement mortar. The environmental HCl reacts with the calcites in SR to produce CaCl₂, CO₂ and H₂O to form more pores under HCl attack, and the environmental Na⁺ cations from Na₂SO₄ go into Si-O-Al network structure, to further enhance the strength of mortar under Na₂SO₄ attack. These results provide the experimental basis for the durability optimization of SR–FFA–GEO mortars.     

河北北部偏远农村留守中小学生心理健康状况调查分析

目的：调查河北北部偏远农村留守中小学生心理健康现状,阐明农村留守中小学生存在的心理问题及其影响因素,为制定有效干预措施提供依据。方法：采用整群分层抽样的方法,抽取河北省北部偏远地区留守学生超过在校学生50%的5所中学和2所小学中的2 040名10～16岁中小学生,运用自制一般情况问卷、心理健康诊断测验(MHT)量表进行问卷调查,分析父母外出打工对留守中小学生心理健康状况的影响。结果：北部偏远农村中小学生留守率为65.69%,农村留守中小学生心理健康状况较差,心理健康问题的检出率为34.50%,非留守学生检出率为14.50%,组间比较差异有统计学意义(P<0.05);父母双方均外出打工的留守中小学生心理症状检出率(38.23%)高于父母单方外出打工的留守学生(29.09%),差异有统计学意义(P<0.05);多因素Logistic回归分析,母亲单方打工和父母双方打工是留守中小学生心理健康问题的危险因素。结论：留守中小学生易发生心理问题,提示留守中小学生心理健康问题值得社会重视。