Predictive functional profiling using marker gene sequences and community diversity analyses of microbes in full-scale anaerobic sludge digesters

Anaerobic digestion (AD) is widely used in treating the sewage sludge, as it can reduce the amount of sludge, eliminate pathogens and produce biofuel. To enhance the operational performance and stability of anaerobic bioreactors, operational and conventional chemical data from full-scale sludge anaerobic digesters were collected over a 2-year period and summarized, and the microbial community diversity of the sludge sample was investigated at various stages of the AD process. For the purpose of distinguishing between the functional and community diversity of the microbes, Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) software was used to impute the prevalence of 16S rDNA marker gene sequences in the difference in various sludge samples. Meanwhile, a taxa analysis was also carried out to investigate the different sludge samples. The microbial community diversity analysis of one AD sludge sample showed that the most dominant bacterial genera were Saccharicrinis, Syntrophus, Anaerotruncus and Thermanaerothrix. Among archaea, acetoclastic Methanosaeta represented 56.0 %, and hydrogenotrophic Methanospirillum, Methanoculleus, Methanothermus and Methanolinea accounted for 41.3 % of all methanogens. The taxa, genetic and functional prediction analyses of the feedstock and AD sludge samples suggested great community diversity differences between them. The taxa of bacteria in two AD sludge samples were considerably different, but the abundances of the functional KEGG pathways took on similar levels. The numbers of identified pathogens were significantly lower in the digested sludge than in the feedstock, but the PICRUSt results showed the difference in “human diseases” abundances in the level-1 pathway between the two sludge samples was small.     

LncRNA NONRATT021972 involved the pathophysiologic processes mediated by P2X<Subscript>7</Subscript> receptors in stellate ganglia after myocardial ischemic injury

Adenosine triphosphate (ATP) acts on P2X receptors to initiate signal transmission. P2X₇ receptors play a role in the pathophysiological process of myocardial ischemic injury. Long noncoding RNAs (lncRNAs) participate in numerous biological functions independent of protein translation. LncRNAs are implicated in nervous system diseases. This study investigated the effects of NONRATT021972 small interference RNA (siRNA) on the pathophysiologic processes mediated by P2X₇ receptors in stellate ganglia (SG) after myocardial ischemic injury. Our results demonstrated that the expression of NONRATT021972 in SG was significantly higher in the myocardial ischemic (MI) group than in the control group. Treatment of MI rats with NONRATT021972 siRNA, the P2X₇ antagonist brilliant blue G (BBG), or P2X₇ siRNA improved the histology of injured ischemic cardiac tissues and decreased the elevated concentrations of serum myocardial enzymes, creatine kinase (CK), CK isoform MB (CK-MB), lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) compared to the MI rats. NONRATT021972 siRNA, BBG, or P2X₇ siRNA treatment in MI rats decreased the expression levels of P2X₇ immunoreactivity, P2X₇ messenger RNA (mRNA), and P2X₇ protein, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and phosphorylated p38 mitogen-activated protein kinase (p38 MAPK) in the SG compared to MI rats. NONRATT021972 siRNA treatment prevented the pathophysiologic processes mediated by P2X₇ receptors in the SG after myocardial ischemic injury.     

蓝细菌病毒A-4L在鱼腥藻(Anabaena variabilis)藻苔中形成同心圆噬斑的成因

摘要:【目的】分析蓝细菌病毒A-4L在鱼腥藻(Anabaena sp.) PCC 7120藻苔中形成同心圆噬斑的原因,阐明A-4L的一个重要生物学特征,为分离、鉴定和筛选新的水华蓝藻病毒提供借鉴。【方法】用初始滴度为2.8×1010PFU/mL的A-4L悬液感染鱼腥藻,在不同时间点收集裂解液绘制一步生长曲线,获得A-4L对鱼腥藻的潜伏期和释放量。将适量A-4L悬液感染不同培养时间的藻苔,逐日观察和记录藻苔病变情况。培养藻苔并接种适量A-4L悬液,分别置于完全持续光照(Light:Dark=24 h:0 h,L:D=24 h:0 h)条件;完全周期光照(L:D=14 h:10h)条件;或前3 d周期光照转后3 d持续光照的条件下,比较不同光照条件对同心圆噬斑形成的影响。然后挑取单个噬斑进行扩大培养,纯化后,负染电镜观察A-4L的超微形态。【结果】A-4L的潜伏期为0.5－2h,释放量约为247 IU/cell (Infectious Units)。在周期光照条件下,藻苔接种A-4L 3－4 d后,出现同心圆噬斑,且同心圆数量与攻毒后的天数(n)有相关性,为“n－1”;同心圆间距约为3 mm。与周期光照条件相比,在持续光照条件下未形成同心圆噬斑。而在周期光照条件转持续光照条件下,由先周期光照时所形成的同心圆在转持续光照后逐渐消失,证实同心圆噬斑的形成依赖于周期光照。负染电镜观察显示A-4L具有一个近似球形的头部,直径约为50 nm以及长度约为10 nm的尾部,形态与短尾蓝细菌病毒相似。【结论】A-4L是一株能形成同心圆噬斑的蓝细菌病毒,并揭示其同心圆噬斑形成的关键条件是周期光照。     

Investigation on the Tribological Behavior and Wear Mechanism of Five Different Veneering Porcelains

Objectives

The primary aim of this research was to investigate the wear behavior and wear mechanism of five different veneering porcelains.

Methods

Five kinds of veneering porcelains were selected in this research. The surface microhardness of all the samples was measured with a microhardness tester. Wear tests were performed on a ball-on-flat PLINT fretting wear machine, with lubrication of artificial saliva at 37°C. The friction coefficients were recorded by the testing system. The microstructure features, wear volume, and damage morphologies were recorded and analyzed with a confocal laser scanning microscope and a scanning electron microscope. The wear mechanism was then elucidated.

Results

The friction coefficients of the five veneering porcelains differ significantly. No significant correlation between hardness and wear volume was found for these veneering porcelains. Under lubrication of artificial saliva, the porcelain with higher leucite crystal content exhibited greater wear resistance. Additionally, leucite crystal size and distribution in glass matrix influenced wear behavior. The wear mechanisms for these porcelains were similar: abrasive wear dominates the early stage, whereas delamination was the main damage mode at the later stage. Furthermore, delamination was more prominent for porcelains with larger crystal sizes.

Significance

Wear compatibility between porcelain and natural teeth is important for dental restorative materials. Investigation on crystal content, size, and distribution in glass matrix can provide insight for the selection of dental porcelains in clinical settings.     

Association between BMP15 Gene Polymorphism and Reproduction Traits and Its Tissues Expression Characteristics in Chicken

BMP15 (Bone morphogenetic protein 15) is an oocyte-secreted growth factor required for ovarian follicle development and ovulation in mammals, but its effects on reproduction in chickens are unclear. In this study, the association between BMP15 polymorphisms and reproduction traits were analyzed, and its expression characteristics in different tissues were explored in LaiWu Black chickens. Three single nucleotide polymorphisms (SNPs) were identified in four hundred LaiWu Black chickens. One SNP (NC_006091.3:g.1773T>C) located in exon 2 which was significantly associated with egg weight at first egg (EWFE) (P = 0.0389), was novel. Diplotypes based on the three SNPs were found to be significantly associated with egg weight at age of 43W (EW43) (P = 0.0058). The chickens with H3H3 diplotype had their first egg 0.57 days later than chickens with H5H5 diplotype and 1.21 days-3.96 days earlier than the other five diplotype chickens. The egg production at age of 43W (E43), egg production at age of 46W (E46) and egg production at age of 48W (E48) for chickens with H3H3 diplotype were the highest among all the chickens, and the E48 of chickens with H3H3 diplotype had 11.83 eggs higher than chickens with H1H5 diplotype. RT-qPCR results showed that the expression level of BMP15 gene in ovarian follicle was in the order of 4 mm>6 mm -8 mm> 15 mm -19 mm> 23 mm -29 mm > 33 mm -34 mm in diameter. The mRNA level in follicles of 4 mm and 6–8 mm in diameter were significantly higher than that in the other follicles (P<0.01). In the same week, the highest mRNA level was found in the ovary, and it was significantly different from that found in the liver and oviduct (P<0.01). Our results indicate that BMP15 plays a vital role in the development of ovary and follicles, especially in the development of primary follicles. H3H3 may be an potential advantageous molecular marker for improving reproduction traits in chickens.     

Proteomic Analysis of Cellular Response Induced by Multi-Walled Carbon Nanotubes Exposure in A549 Cells

The wide application of multi-walled carbon nanotubes (MWCNT) has raised serious concerns about their safety on human health and the environment. However, the potential harmful effects of MWCNT remain unclear and contradictory. To clarify the potentially toxic effects of MWCNT and to elucidate the associated underlying mechanisms, the effects of MWCNT on human lung adenocarcinoma A549 cells were examined at both the cellular and the protein level. Cytotoxicity and genotoxicity were examined, followed by a proteomic analysis (2-DE coupled with LC-MS/MS) of the cellular response to MWCNT. Our results demonstrate that MWCNT induces cytotoxicity in A549 cells only at relatively high concentrations and longer exposure time. Within a relatively low dosage range (30 µg/ml) and short time period (24 h), MWCNT treatment does not induce significant cytotoxicity, cell cycle changes, apoptosis, or DNA damage. However, at these low doses and times, MWCNT treatment causes significant changes in protein expression. A total of 106 proteins show altered expression at various time points and dosages, and of these, 52 proteins were further identified by MS. Identified proteins are involved in several cellular processes including proliferation, stress, and cellular skeleton organization. In particular, MWCNT treatment causes increases in actin expression. This increase has the potential to contribute to increased migration capacity and may be mediated by reactive oxygen species (ROS).     

Feasibility assessment and implementation strategies of green care in rural Taiwan

Pursuing the rural idyll for retirement is especially a popular age-old dream for Taiwan people. Farming for health is an emerging trend, which drivers to initiate a green care service based on a combination of agriculture resources and traditional care. The purposes of this study were to assess the feasibility of green care in rural communities and to propose implementation strategies for varied rural area types in Taiwan. This study was conducted with two stags. A feasibility study comprising two aspects of political and environmental feasibilities was assessed in the first stage. The political feasibility was assessed based on social demand and government policies. Accordingly, three alternative models for senior green care participation were proposed, including green occupational therapy (for residents), rural long-stay tourism (for tourists), and agricultural working holiday (for volunteers). The environmental feasibility assessment was conducted in 102 rural communities in northern Taiwan. Five indexes, including the natural environment, rural resources, public facilities, senior care, and community capacity, were used to evaluate the potential of communities for developing green care. The results showed that green care implementing active aging in place in rural areas is feasible. Seventeen communities with plentiful or unique rural resources and high-quality community capacity were recommended as potential communities. In the second stage, a multiple case study was conducted in three communities representing different alternative models of green care. The community leader interviews, on-site investigations, vision forum, and operation workshop were adopted to propose the implementation strategies of green care for three communities, respectively, including human resource, volunteer or tourist management, revenue distribution, and marketing.