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Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), a nitroamine explosive, is commonly detected in groundwater at military testing and training sites. The objective of this study was to characterize the microbial community capable of using nitrogen derived from the RDX or RDX intermediates during in situ bioremediation. Active groundwater microorganisms capable of utilizing nitro-, ring- or fully-labeled 15 N-RDX as a nitrogen source were identified using stable isotope probing (SIP) in groundwater microcosms prepared from two wells in an aquifer previously amended with cheese whey to promote RDX biodegradation. A total of fifteen 16S rRNA gene sequences, clustered in Clostridia , β- Proteobacteria , and Spirochaetes , were derived from the 15 N-labeled DNA fractions, suggesting the presence of metabolically active bacteria capable of using RDX and/or RDX intermediates as a nitrogen source. None of the derived sequences matched RDX-degrading cultures commonly studied in the laboratory, but some of these genera have previously been linked to RDX degradation in site groundwater via 13 C-SIP. When additional cheese whey was added to the groundwater samples, 28 sequences grouped into Bacteroidia , Bacilli , and α-, β-, and γ- Proteobacteria were identified. The data suggest that numerous bacteria are capable of incorporating N from ring- and nitro-groups in RDX during anaerobic bioremediation, and that some genera may be involved in both C and N incorporation from RDX. [ABSTRACT FROM AUTHOR]

This study investigated two possible strategies, increasing ammonia oxidation activity and bioaugmenting with triclosan-degrader Sphingopyxis strain KCY1, to enhance triclosan removal in nitrifying activated sludge (NAS). Triclosan (2 mg L −1 ) was removed within 96-h in NAS bioreactors amended with 5, 25 and 75 mg L −1 of ammonium (NH 4 –N). The fastest triclosan removal was observed in 25 mg NH 4 –N L −1 amended-bioreactors where high ammonia oxidation occurred. Inhibition of ammonia oxidation and slower triclosan removal were observed in 75 mg NH 4 –N L −1 amended-bioreactors. Triclosan removal was correlated to the molar ratio of the amount of nitrate produced to the amount of ammonium removed. Bioaugmentation with strain KCY1 did not enhance triclosan removal in the bioreactors with active ammonia oxidation. Approximately 36–42% and 59% of triclosan added were removed within 24-h by ammonia-oxidizing bacteria and unknown triclosan-degrading heterotrophs, respectively. The results suggested that increasing ammonia oxidation activity can be an effective strategy to enhance triclosan removal in NAS. [ABSTRACT FROM AUTHOR]

Abstract: We employed stable isotope probing (SIP) with 13C-labeled hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) to identify active microorganisms responsible for RDX biodegradation in groundwater microcosms. Sixteen different 16S rRNA gene sequences were derived from microcosms receiving 13C-labeled RDX, suggesting the presence of microorganisms able to incorporate carbon from RDX or its breakdown products. The clones, residing in Bacteroidia, Clostridia, α-, β- and δ-Proteobacteria, and Spirochaetes, were different from previously described RDX degraders. A parallel set of microcosms was amended with cheese whey and RDX to evaluate the influence of this co-substrate on the RDX-degrading microbial community. Cheese whey stimulated RDX biotransformation, altered the types of RDX-degrading bacteria, and decreased microbial community diversity. Results of this study suggest that RDX-degrading microorganisms in groundwater are more phylogenetically diverse than what has been inferred from studies with RDX-degrading isolates. [Copyright &y& Elsevier]

Abstract: Introduction: Recent studies have reported the color change and formation of precipitates containing para-chloroaniline (PCA) after a reaction of sodium hypochlorite (NaOCl) and chlorhexidine (CHX). Alexidine (ALX), a biguanide disinfectant similar to CHX, has greater affinity for bacterial virulence factors than CHX. This study determined by electrospray ionization mass spectrometry (ESI-MS) and scanning electron microscopy (SEM) whether the chemical interaction between ALX and NaOCl results in PCA or precipitates. Methods: ESI-MS was performed on 4 different concentrations of ALX (1%, 0.5%, 0.25%, and 0.125%) with 4% NaOCl to detect the presence of PCA. As control groups, 1% ALX, 0.5% PCA, and a mixture of 2% CHX and 4% NaOCl were analyzed. The formation of precipitates on the dentinal surfaces of premolar root canals treated with the solutions of ALX and NaOCl (AN) or CHX and NaOCl (CN) was observed by SEM and the color change in the reaction solutions was also analyzed. Results: ESI-MS showed that the peak (mass/charge ratio = 128.026) in the PCA spectrum was not detected in any of the 4 AN solutions, whereas the peak was found in the CN solution. SEM revealed precipitates covering dentinal surfaces in the CN solution. The AN solutions produced no precipitate. The AN solutions changed in color from light yellow to transparent with decreasing ALX concentration, whereas peach-brown discoloration was observed in the CN solution. Conclusions: The interaction of ALX and NaOCl did not produce PCA or precipitates, and the color of the reacted solution changed transparent with decreasing ALX concentration. [Copyright &y& Elsevier]

Abstract: It is a generally accepted result that the inclusion of rubber particles causes the concrete to degrade physical properties of the concrete. In this study the crumb rubber was partially oxidized and used as additives of mortars. Dramatically, the compressive strength of the rubberized mortars (with 6wt.%) was greater than that of mortars without the crumb rubber. To understand these phenomena, Fourier Transform Infrared Spectroscopy (FTIR) was used to explore the functional groups on surfaces of the crumb rubber, and Scanning Electron Microscopy (SEM) was used to observe microstructures of mortars. With the partial oxidation treatment, rubber surfaces produced hydrophilic functional groups as indicated by IR spectra and the hydration of the cement near the crumb rubber was enhanced as shown by SEM, leading to stronger mortars. [ABSTRACT FROM AUTHOR]

Abstract: The International Commission on Radiological Protection (ICRP) published the new recommendations 2007 on radiological protection. International Atomic Energy Agency (IAEA) is also under process in revising its International Basic Safety (BSS). According to revision of the ICRP recommendations and BSS, the Korean government plans to implement those changes. In the 2007 ICRP recommendations, there are some new concepts, principles and quantities. Based on the study carried out by Korea Institute of Nuclear Safety (KINS) so far, the following points are identified as major areas that need further in-depth review and consideration for the implementation of the ICRP 2007 recommendations into Korean radiation protection laws and regulations; changes in the radiation risk factors, radiation weighting factors and tissue weighting factors, maintenance of the ICRP 60 dose limits, practical application of the dose constraints and determination of the reference levels in many source to individual exposure relationships, change from process-based system to exposure situation-based system, strengthening of the principle of optimization in all exposure situations, system of radiation protection for the environment, practical application of the exclusion and exemption principles, active participation of the stakeholders, changes in glossary etc. The study for the implementation of the ICRP 2007 recommendations into national legislations will be conducted till the end of 2012. In the meantime, draft regulations will be developed and the possible impact on the nuclear industry will also be analyzed and active involvement of the stakeholders including licensees will be encouraged in the entire process. The final draft of the revised laws and regulations will be issued in the early of 2013 and the formal legislation process of this final draft will commence in due course. [Copyright &y& Elsevier]

Abstract: Periprosthetic fracture is a relatively rare but well-recognized complication after knee joint arthroplasty. We experienced a case of medial femoral condylar fracture among 700 cases of unicompartmental knee arthroplasty (UKA). The patient was a 56-year-old woman who underwent minimally invasive UKA for medial osteoarthritis of the knee. A displaced medial femoral condylar fracture occurred 3 years after UKA. A closed reduction and percutaneous fixation using 3 cannulated cancellous screws was performed. Union of the fracture was achieved, and a full recovery of knee motion was gained after 3 months. The Knee Society knee and function scores were 87 and 80, respectively, at the 2-year follow-up. They were the same as the scores before the fracture took place, and there was no evidence of component loosening or ligament instability. [Copyright &y& Elsevier]

Highlights: [•] Strain PD630 can tolerate low concentration of five model inhibitory compounds. [•] Strain PD630 can use vanillic acid and TPCA for cell growth and TAG accumulation. [•] Vanillin can be used as a carbon source, but TAGs are not accumulated. [•] Strain PD630 can grow on three lignocellulosic hydrolysates and accumulate TAGs. [Copyright &y& Elsevier]

The fiber of paper mulberry, which is mostly grown in the East Asian region, varies in both length and width—even if from the same species—depending on the country, soil, and climate where it is grown. This accounts for differences in the quality of handmade paper between domestic and imported products. Once handmade paper is manufactured as sheets, its origin cannot be determined from a morphological perspective, regardless of macroscopic and microscopic observations. Therefore, this study attempted to determine the origin of Korean and imported products using mulberry bast fiber and handmade paper from a chemometrics perspective. The inorganic components of wood are absorbed from the soil and exist in the bark of trees; thus, metal and rare-earth elements in the bast fibers and handmade papers were quantitatively analyzed using inductively coupled plasma-atomic emission spectroscopy/mass spectrometry (ICP-AES/MS). Following this, a prediction model of their origin was constructed by applying multivariate statistical analysis, i.e., a partial least squares-discriminant analysis (PLS-DA) loading plot was constructed, which helped in identifying the discrimination factors resulting from their origin. According to the ICP-AES results, Pb was only detected in the Gyeongbuk Mungyeong dak sample of the Korean bast fibers. The Chinese bast fiber sample had high contents of Ca, and B and Zn were detected only in the Chinese bast fiber samples. Bast fiber samples from China, Japan, and Thailand showed relatively high contents of Al, Ca, and Na. Meanwhile, Cu and Zn were detected in the handmade paper manufactured from the imported materials. According to the ICP-MS results, among the Korean handmade papers, the products from Gyeongbuk Mungyeong, Andong, and Chungbuk Goesan exhibited a high U content and that from Gapyeong had high Sc, Rb, Sr, and Ba contents. Thus, the elemental analysis employed in this study effectively identified the origin of the papers. The origin prediction by PLS-DA for the domestic and imported products revealed an accuracy of 86.4% and 72.7% for ICP-AES and ICP-MS methods, respectively, which is deemed acceptable to assess the origin. We believe this method significantly contributes to determining the origin of paper mulberry bast fiber and handmade paper manufactured in East Asia. [ABSTRACT FROM AUTHOR]

Trichloroethylene (TCE) is one of the most ubiquitous halogenated organic compounds of concerns of carcinogens in groundwater in Taiwan. Bioremediation has been recognized as a cost-effective approach in reducing TCE concentration. Five pilot-scale wells were constructed to monitor TCE concentrations in contaminated groundwater. With injection of EOS®, TCE was effectively degraded to 42%–93% by the end of 175 days. The biostimulation with EOS® was useful in establishing a micro-site anaerobic but with limited contribution. Dilution of the aquifer movement also caused the TCE reduction among injection and monitoring wells. The degradability was affected by the location and the proximity from the injection well. TCE concentrations found to be negatively correlated with the associated Dehalococcoides spp. and functional genes levels. Dhc concentration of 108 copies L−1 caused the initial 40% of TCE degradation. The well with the optimal degradation owned tceA of 109 cells L−1. T-RFLP results indicate the wells with the superior TCE degradability also performed the highest Shannon index number (means the highest diversity), which occurred on the same day that Dhc levels started to enlarge. Desulfovibrio desulfuricans and Desulfuromonas chloroethenica were predominant species identified in the T-RFLP fingerprint profile. In brief, a variety of different factors including well locations, geochemical indicators, and microbial contribution were useful to explain the site-specific optimal TCE remediation approach. The consistence among TCE degradation, Dhc growing pattern, functional gene levels, and the dynamics of the microbial community structure present the novelty of this study. • TCE degradation achieved approximately 40% when Dehalococcoides sp. levels achieved 108 copies L−1. • T-RFLP results indicate the superior TCE degradability correlated with the highest diversity estimated by H index. • Desulfovibrio desulfuricans and Desulfuromonas chloroethenica were predominant species in the T-RFLP profile. • The TCE degradation of 42%-93% was due to EOS® injection in a micro-site anaerobic condition and dilution of the aquifer. [ABSTRACT FROM AUTHOR]

In this study, we report on the first chemical synthesis of ultra-short pyrazole-arginine based antimicrobial peptidomimetics derived from the newly synthesized N -alkyl/aryl pyrazole amino acids. Through the systematic tuning of hydrophobicity, charge, and peptide length, we identified the shortest peptide Py11 with the most potent antimicrobial activity. Py11 displayed greater antimicrobial activity against antibiotic-resistant bacteria, including MRSA, MDRPA, and VREF, which was approximately 2–4 times higher than that of melittin. Besides its higher selectivity (therapeutic index) toward bacterial cells than LL-37, Py11 showed highly increased proteolytic stability against trypsin digestion and maintained its antimicrobial activity in the presence of physiological salts. Interestingly, Py11 exhibited higher anti-biofilm activity against MDRPA compared to LL-37. The results from fluorescence spectroscopy and transmission electron microscopy (TEM) suggested that Py11 kills bacterial cells possibly by integrity disruption damaging the cell membrane, leading to the cytosol leakage and eventual cell lysis. Furthermore, Py11 displayed significant anti-inflammatory (endotoxin-neutralizing) activity by inhibiting LPS-induced production of nitric oxide (NO) and TNF-α. Collectively, our results suggest that Py11 may serve as a model compound for the design of antimicrobial and antisepsis agents. [ABSTRACT FROM AUTHOR]

Enterococcus faecalis is associated with refractory apical periodontitis and its lipoteichoic acid (Ef.LTA) is considered as a major virulence factor. Although the binding proteins of Ef.LTA may play an important role for mediating infection and immunity in the oral cavity, little is known about Ef.LTA-binding proteins (Ef.LTA-BPs) in saliva. In this study, we identified salivary Ef.LTA-BPs with biotinylated Ef.LTA (Ef.LTA-biotin) through mass spectrometry. The biotinylation of Ef.LTA was confirmed by binding capacity with streptavidin-FITC on CHO/CD14/TLR2 cells. The biological activity of Ef.LTA-biotin was determined based on the induction of nitric oxide and macrophage inflammatory protein-1α in a macrophage cell-line, RAW 264.7. To identify salivary Ef.LTA-BPs, the Ef.LTA-biotin was mixed with a pool of human saliva obtained from nine healthy subjects followed by precipitation with a streptavidin-coated bead. Ef.LTA-BPs were then separated with 12% SDS-PAGE and subjected to the mass spectrometry. Six human salivary Ef.LTA-BPs including short palate lung and nasal epithelium carcinoma-associated protein 2, zymogen granule protein 16 homolog B, hemoglobin subunit α and β, apolipoprotein A-I, and lipocalin-1 were identified with statistical significance ( P < 0.05). Ef.LTA-BPs were validated with lipocalin-1 using pull-down assay. Hemoglobin inhibited the biofilm formation of E. faecalis whereas lipocalin-1 did not show such effect. Collectively, the identified Ef.LTA-BPs could provide clues for our understanding of the pathogenesis of E. faecalis and host immunity in oral cavity. [ABSTRACT FROM AUTHOR]

Peptidoglycan (PGN) is a major cell wall component of Gram-positive bacteria that contributes to the regulation of host immunity in the gastrointestinal tract (GIT). Although Gram-positive bacteria contain structurally distinct PGNs that are considered to differently interact with the GIT, PGN-binding proteins (PGN-BPs) in the GIT have been poorly understood. In the present study, we purified PGNs from Lactobacillus plantarum and Staphylococcus aureus (named as Lp.PGN and Sa.PGN, respectively) and identified Lp.PGN-BPs and Sa.PGN-BPs in the lysate of mouse GIT. Lp.PGN activated nucleotide-binding oligomerization domain (NOD) 1 and NOD2, whereas Sa.PGN activated NOD2, but not NOD1, implying that both PGNs retained the biological activity and were differently recognized by the host cells. PGN-BPs were isolated by precipitation with Lp.PGN or Sa.PGN and identified using LTQ-Orbitrap hybrid Fourier transform mass spectrometry. Three independent experiments demonstrated that 18 Lp.PGN-BPs and 6 Sa.PGN-BPs were reproducibly obtained with statistical significance ( P < 0.05). Both Lp.PGN and Sa.PGN bound to proteins which are related to cytoskeleton, microbial adhesion, and mucosal integrity. Lp.PGN selectively bound to proteins related to gene expression, chaperone, and antimicrobial function. However, Sa.PGN preferentially interacted with proteins involved in adherence and invasion of pathogens. Collectively, these results suggest that bacterial PGNs interact with the proteins regulating mucosal homeostasis and immunity in the gut and PGNs of commensals and pathogens might be also differentially recognized in the GIT. [ABSTRACT FROM AUTHOR]

Abstract: Porphyromonas gingivalis causes periodontal diseases and its lipopolysaccharide (LPS) is considered as a major virulence factor responsible for pathogenesis. Since initial recognition of P. gingivalis LPS (Pg.LPS) in the oral cavity might be crucial for the host response, we identified Pg.LPS-binding proteins (Pg.LPS-BPs) using Pg.LPS-immobilized beads and a high-resolution mass spectrometry. LPS purified from P. gingivalis was conjugated onto N-hydroxysuccinimidyl-Sepharose® 4 Fast Flow beads. Notably, Pg.LPS-conjugated beads could stimulate Toll-like receptor 2 (TLR2) as determined by a TLR2-depdendent reporter expression system using CHO/CD14/TLR2. In addition, the Pg.LPS-conjugated beads induced the production of inflammatory mediators such as nitric oxide and interferon-gamma-inducible protein-10 in the macrophage cell-line, RAW 264.7. These results imply that Pg.LPS retained its immunological properties during the conjugation process. Then, the Pg.LPS-conjugated beads were mixed with a pool of saliva obtained from nine human subjects to capture Pg.LPS-BPs and molecular identities were determined by LTQ-Orbitrap hybrid fourier transform mass spectrometry. Pg.LPS-BPs captured at high frequencies included alpha-amylase, cystatin, prolactin-inducible protein, lysozyme C, immunoglobulin components, serum albumin, lipocalin-1, and submaxillary gland androgen-regulated protein 3B. These proteins are known to be involved in bacterial adhesion and colonization, anti-microbial functions or modulation of immune responses. [Copyright &y& Elsevier]

Abstract: This study attempted to validate a new method for patient-tailored efficiency calibration. Digital calibration with Monte Carlo simulations was used to substitute the lack of precision limitation due to the limited number of experimental phantoms in whole body counting calibration for internal dosimetry. The validity of this approach was examined by comparing the simulation results to the measured values from actual measurements using family BOMAB phantoms. The computational voxel phantoms were constructed by a reconstruction technique using AP and lateral photographic images of the BOMAB phantoms, instead of using the given specifications provided with BOMAB phantoms. Although discrepancies to a certain degree between the computational simulation and measured efficiencies do exist, the results support the new approach of being an alternative to family BOMAB phantoms. [Copyright &y& Elsevier]

Abstract: The natural soil mineral conditioner illite effectively improved the germination and growth of lettuce when applied in particulate or powdered form. When illite was given in particulate and powdered forms, the germination rate of lettuce seeds improved remarkably up to 93% and 133%, respectively. Contrary to the developmental effects, the growth rate of lettuce treated with particulate illite improved slightly by 23%; powdered illite had no significant effects on lettuce growth rate. Thus, illite primarily affects seed germination rather than the growth of lettuce. To examine illite-induced proteins related to lettuce growth, differentially expressed proteins in lettuce leaves were analyzed by two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption ionization-time of flight/time of flight mass spectrometry (MALDI-TOF/TOF MS) followed by Mascot search. From the proteomic analysis, five down-regulated proteins were identified related to storage protein, carbon metabolism and energy conversion. Three up-regulated proteins were related to energy production/conversion and carbon fixation. These results demonstrate that illite treatment as a soil conditioner helps lettuce seed germination and lettuce growth by regulating carbon metabolic flux. [Copyright &y& Elsevier]

Enhanced monitored natural attenuation was conducted with molasses injections to an in situ trichloroethylene (TCE)-contaminated groundwater site. Three pilot-scale wells were conducted for monitoring and substrate injections. At most 97.0% of the TCE was effectively degraded after about 600 days. TCE detected in the injection wells attained Tier 2 Groundwater Regulation in Taiwan for non-drinking water sources. The reaction rates of Cl–VOCs in one of the injection wells explained the mechanism how these dechlorinating species transferred TCE to cis-DCE and VC in anaerobic conditions. The magnitude of the 1st order kinetic growth rates of Dehalococcoides (Dhc) were consistent with the associated TCE degradability. The qPCR and T-RFLP results concluded existence of crucial dechlorinating species including Dhc, which performed critical level of 106 copy L−1 to trigger the TCE degradation. The detected t ceA and vcrA ranging from 2.07 × 103 to 6.57 × 105 copy L−1confirmed the pathway of TCE degradation. The two injection wells with the optimal TCE degradation showed increases of bacterial diversity estimated by the Shannon Index. The Shannon index explained the superiority of an increased bacterial diversity. The nonmetric multidimensional scaling results suggested that the bacterial dynamic was affected by the TCE degradation stages. The bacterial community structures were analogous when TCE was well degraded. • The molecular results provided evidence of existence of crucial dechlorinating species including Dehalococcoides spp. • Dehalococcoides spp. With the critical abundance of 106 copy L−1 was critical for TCE degradation. • Detections of tceA (as high as 107 copy L−1) and vcrA confirmed the pathway of TCE degradation. • The optimal TCE degradation was observed with increases of bacterial diversity estimated by the Shannon Index. • Nonmetric multidimensional scaling result indicated the bacterial community dynamic depended on the TCE degradation stages. [ABSTRACT FROM AUTHOR]