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INTRODUCTION: The worldwide prevalence of periodontitis is considerably high, and its pathogenic mechanisms must be investigated and understood in order to improve clinical treatment outcomes and reduce the disease prevalence and burden. The exacerbation of the host immune system induced by oral microbial dysbiosis and the subsequent tissue destruction are the hallmarks of the periodontitis. However, the oral bacteria involved in periodontitis are not fully understood. We used the Oxford Nanopore Technologies (ONT) sequencing system to analyze metagenomic information in subgingival dental plaque from periodontitis and non-periodontitis patients. The number of Lactobacillus zeae (L. zeae) in the periodontitis patients was 17.55-fold higher than in the non-periodontitis patients, suggesting that L. zeae is a novel periodontitis-associated pathogen. Although several Lactobacillus species are used in vivo as probiotics to treat periodontitis and compete with Porphyromonas gingivalis (P. gingivalis), the roles of L. zeae in periodontitis progression, and the relationship between L. zeae and P. gingivalis needs to be investigated. METHODS: Both L. zeae and P. gingivalis were inoculated in the ligature-implant site of periodontitis mice. We collected mouse gingival crevicular fluid to analyze inflammatory cytokine secretion using a multiplex assay. Intact or sliced mouse maxilla tissue was used for micro-computed tomography analysis or hematoxylin and eosin staining, immunohistochemistry, and tartrate-resistant acid phosphatase staining to evaluate alveolar bone loss, neutrophil infiltration, and osteoclast activation, respectively. RESULTS: We observed that L. zeae competed with P. gingivalis, and it increased inflammatory cytokine secretion at the ligature-implant site. Similar to P. gingivalis, L. zeae promoted ligature-induced neutrophile infiltration, osteoclast activation, and alveolar bone loss. DISCUSSION: We, therefore, concluded that L. zeae accelerated the progression of periodontitis in the ligature-induced periodontitis mouse model.

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This study explored the potential reactivities of various reductants in inducing subsurface TCE degradation in natural soils. It was found that bisulfite (HSO3-) exhibited the ability to induce reduction in soil iron minerals, and increase the degradation of TCE in the soil slurry system; however, no TCE degradation occurred in the aqueous system. The role of TCE degradation by soil constituents, such as major soil mineral elements, Fe and humic acid (HA) on HSO3-, was examined in aqueous phase. It was seen that by themselves, the presence of Fe3+, HA, Fe2O3, FeOOH, and Fe3O4 did not result in substantial TCE removals. However, the presence of HSO3- can significantly induce iron reduction, producing a reducing condition that can result in complete TCE degradation. Furthermore, the reductive pathway was identified as the dominant degradation route via electron scavenging with periodate ion. To demonstrate the applicability of HSO3- reduction enhancement, a HSO3-/TCE mixed solution was flushed through a soil column, with gradually increased HSO3- concentrations, at a fixed flow rate, and also with varied flushing rates at a fixed HSO3- concentration. Based on our study, a 10 mM HSO3- solution may be effective for some environmental sites; however, each site requires specific evaluation based on contaminant concentrations and subsurface conditions.

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Passive sampling (PS) is a method employed to detect volatile organic compounds in groundwater and soil gas. This study attempted to manufacture a polydimethylsiloxane (PDMS) dialysis passive sampler for potential application in detecting trichloroethylene (TCE) in aqueous and gaseous phases. The equilibrium time of the passive sampler was initially determined, followed by multilayer passive sampling in a three-dimensional sandbox to construct a tomography of TCE vapor spatial distribution in the vadose zone above the saturated water level. The results indicated that an equilibrium time period of >10 d was required in the aqueous phase containing TCE concentrations ranging from 3 to 25 mg L-1, while an equilibrium time period of >12 d was necessary for TCE vapor concentrations ranging from 2.6-26 mg L-1. Therefore, a 14 d of equilibrium time was suggested for application of this passive sampler in detecting vapor and aqueous phase TCE. After collection of the passive samples from the three-dimensional sandbox, a three dimensional visualization was created, and it was demonstrated to be a reasonable way to simulate a three dimensional TCE distribution. It was confirmed that the passive sampler developed in this study is effective for assessing TCE contamination in the subsurface.

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Thermoresponsive poly(2-(N-alkylacrylamide) ethyl acetate)s with different N-alkyl groups, including poly(2-(N-methylacrylamide) ethyl acetate) (PNMAAEA), poly(2-(N-ethylacrylamide) ethyl acetate) (PNEAAEA), and poly(2-(N-propylacrylamide) ethyl acetate) (PNPAAEA), as well as poly(N-acetoxylethylacrylamide) (PNAEAA), were synthesized by solution RAFT polymerization. Unexpectedly, it was found that there are induction periods in the RAFT polymerization of these monomers, and the induction time correlates with the length of the N-alkyl groups in the monomers and follows the order of NAEAA < NMAAEA < NEAAEA < NPAAEA. The solubility of poly(2-(N-alkylacrylamide) ethyl acetate)s in water is also firmly dependent on the length of the N-alkyl groups. PNPAAEA including the largest N-propyl group is insoluble in water, whereas PNMAAEA and PNEAAEA are thermoresponsive in water and undergo the reversible soluble-to-insoluble transition at a critical solution temperature. The cloud point temperature (Tcp) of the thermoresponsive polymers is in the order of PNEAAEA < PNAEAA < PNMAAEA. The parameters affecting the Tcp of thermoresponsive polymers, e.g., degree of polymerization (DP), polymer concentration, salt, urea, and phenol, are investigated. Thermoresponsive PNMAAEA-b-PNEAAEA block copolymer and PNMAAEA-co-PNEAAEA random copolymers with different PNMAAEA and/or PNEAAEA fractions are synthesized, and their thermoresponse is checked.

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BACKGROUND: Mesangial proliferative glomerulonephritis (MePGN) is characterized by excessive mesangial cell proliferation and mesangial matrix expansion, which lead to glomerular sclerosis and obliteration and, in turn, to deteriorating renal function. To identify and quantify the total proteins in renal tissues of MePGN patients, we used isobaric tags for relative and absolute quantification (iTRAQ) technology, and then looked for differentially expressed proteome profiles in MePGN patients. METHODS: Eight-plex iTRAQ coupled with multiple chromatographic fractionation and tandem mass spectrometry was used to analyze total proteins in renal tissues of MePGN patients. Proteins were identified using Mascot, compared to show any differential expression. RESULTS: Among 512 distinct proteins identified, 113 proteins were up-regulated or down-regulated with a onefold or more alteration in levels across groups. Among of them, there was significant variation in our present iTRAQ study, which contains lamin A, actin, profilin-1, annexin-A1 and A2 up-regulated, and antiquitin and aldolase B down-regulated. CONCLUSION: iTRAQ-based quantitative proteomic technology is efficiently applicable for protein identification and relative quantitation of proteomes of renal tissue. Differentially expressed proteome profiles of MePGN patients are determined. Further investigation of the molecular mechanism of the involved proteins may help to better understand the pathogenesis of MePGN and to discover novel biomarker candidates, which may enable the development of new approaches to diagnosis of MePGN.

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