Science.gov

Sample records for 01llb k58 h21

  1. MD-2 as the target of a novel small molecule, L6H21, in the attenuation of LPS-induced inflammatory response and sepsis

    PubMed Central

    Wang, Yi; Shan, Xiaoou; Chen, Gaozhi; Jiang, Lili; Wang, Zhe; Fang, Qilu; Liu, Xing; Wang, Jingying; Zhang, Yali; Wu, Wencan; Liang, Guang

    2015-01-01

    Background and Purpose Myeloid differentiation 2 (MD-2) recognizes LPS, which is required for TLR4 activation, and represents an attractive therapeutic target for severe inflammatory disorders. We previously found that a chalcone derivative, L6H21, could inhibit LPS-induced overexpression of TNF-α and IL-6 in macrophages. Here, we performed a series of biochemical experiments to investigate whether L6H21 specifically targets MD-2 and inhibits the interaction and signalling transduction of LPS-TLR4/MD-2. Experimental Approach The binding affinity of L6H21 to MD-2 protein was analysed using computer docking, surface plasmon resonance analysis, elisa, fluorescence measurements and flow cytometric analysis. The effects of L6H21 on MAPK and NF-κB signalling were determined using EMSA, fluorescence staining, Western blotting and immunoprecipitation. The anti-inflammatory effects of L6H21 were confirmed using elisa and RT-qPCR in vitro. The anti-inflammatory effects of L6H21 were also evaluated in septic C57BL/6 mice. Key Results Compound L6H21 inserted into the hydrophobic region of the MD-2 pocket, forming hydrogen bonds with Arg90 and Tyr102 in the MD-2 pocket. In vitro, L6H21 subsequently suppressed MAPK phosphorylation, NF-κB activation and cytokine expression in macrophages stimulated by LPS. In vivo, L6H21 pretreatment improved survival, prevented lung injury, decreased serum and hepatic cytokine levels in mice subjected to LPS. In addition, mice with MD-2 gene knockout were universally protected from the effects of LPS-induced septic shock. Conclusions and Implications Overall, this work demonstrated that the new chalcone derivative, L6H21, is a potential candidate for the treatment of sepsis. More importantly, the data confirmed that MD-2 is an important therapeutic target for inflammatory disorders. PMID:26076332

  2. Genetic diversity and virulence potential of shiga toxin-producing Escherichia coli O113:H21 strains isolated from clinical, environmental, and food sources.

    PubMed

    Feng, Peter C H; Delannoy, Sabine; Lacher, David W; Dos Santos, Luis Fernando; Beutin, Lothar; Fach, Patrick; Rivas, Marta; Hartland, Elizabeth L; Paton, Adrienne W; Guth, Beatriz E C

    2014-08-01

    Shiga toxin-producing Escherichia coli strains of serotype O113:H21 have caused severe human diseases, but they are unusual in that they do not produce adherence factors coded by the locus of enterocyte effacement. Here, a PCR microarray was used to characterize 65 O113:H21 strains isolated from the environment, food, and clinical infections from various countries. In comparison to the pathogenic strains that were implicated in hemolytic-uremic syndrome in Australia, there were no clear differences between the pathogens and the environmental strains with respect to the 41 genetic markers tested. Furthermore, all of the strains carried only Shiga toxin subtypes associated with human infections, suggesting that the environmental strains have the potential to cause disease. Most of the O113:H21 strains were closely related and belonged in the same clonal group (ST-223), but CRISPR analysis showed a great degree of genetic diversity among the O113:H21 strains.

  3. Genetic Diversity and Virulence Potential of Shiga Toxin-Producing Escherichia coli O113:H21 Strains Isolated from Clinical, Environmental, and Food Sources

    PubMed Central

    Delannoy, Sabine; Lacher, David W.; dos Santos, Luis Fernando; Beutin, Lothar; Fach, Patrick; Rivas, Marta; Hartland, Elizabeth L.; Paton, Adrienne W.; Guth, Beatriz E. C.

    2014-01-01

    Shiga toxin-producing Escherichia coli strains of serotype O113:H21 have caused severe human diseases, but they are unusual in that they do not produce adherence factors coded by the locus of enterocyte effacement. Here, a PCR microarray was used to characterize 65 O113:H21 strains isolated from the environment, food, and clinical infections from various countries. In comparison to the pathogenic strains that were implicated in hemolytic-uremic syndrome in Australia, there were no clear differences between the pathogens and the environmental strains with respect to the 41 genetic markers tested. Furthermore, all of the strains carried only Shiga toxin subtypes associated with human infections, suggesting that the environmental strains have the potential to cause disease. Most of the O113:H21 strains were closely related and belonged in the same clonal group (ST-223), but CRISPR analysis showed a great degree of genetic diversity among the O113:H21 strains. PMID:24858089

  4. Characterization of a verocytotoxin-producing enteroaggregative Escherichia coli serogroup O111:H21 strain associated with a household outbreak in Northern Ireland.

    PubMed

    Dallman, Tim; Smith, Geoffrey P; O'Brien, Brendan; Chattaway, Marie A; Finlay, David; Grant, Kathie A; Jenkins, Claire

    2012-12-01

    A strain of Escherichia coli O111:H21 recently isolated in the United Kingdom harbored the phage-encoded vtx2c gene and the aggregative adherence plasmid. Although exhibiting the same pathogenic profile as the E. coli O104:H4 strain linked to the outbreak in Germany, there were important differences in strain characteristics and in the epidemiological setting.

  5. From Planar to Cage in 15 Easy Steps: Resolving the C60H21F9(-) → C60(-) Transformation by Ion Mobility Mass Spectrometry.

    PubMed

    Greisch, Jean-François; Amsharov, Konstantin Yu; Weippert, Jürgen; Weis, Patrick; Böttcher, Artur; Kappes, Manfred M

    2016-09-01

    A combination of mass spectrometry, collision-induced dissociation, ion mobility mass spectrometry (IM-MS), and density functional theory (DFT) has been used to study the evolution of anionic species generated by laser-desorption of the near-planar, fluorinated polycyclic aromatic hydrocarbon (PAH), C60H21F9 (s). The dominant decay process for isolated, thermally activated C60H21F9(-) species comprises a sequence of multiple regioselective cyclodehydrofluorination and cyclodehydrogenation reactions (eliminating HF and H2, respectively, while forming additional pentagons and/or hexagons). The DFT calculations allow us to set narrow bounds on the structures of the resulting fragment ions by fitting structural models to experimentally determined collision cross sections. These show that the transformation of the precursor anion proceeds via a series of intermediate structures characterized by increasing curvature, ultimately leading to the closed-shell fullerene cage C60(-) as preprogrammed by the precursor structure. PMID:27501376

  6. Characterization of a chromosomally integrated luxCDABE marker for investigation of shiga toxin-producing Escherichia coli O91:H21 shedding in cattle

    NASA Astrophysics Data System (ADS)

    Hong, Yingying; Mathew, Alan G.

    2011-06-01

    Shiga toxin-producing Escherichia coli (STEC) O91:H21 has been recognized as a potential life-threatening foodborne pathogen and is commonly involved in human infections in European countries. Fecal shedding of the organism by cattle is considered to be the ultimate source for contaminations. Studies examining STEC shedding patterns often include inoculation of strains carrying antibiotic resistance makers for identifiable recovery. However, indigenous intestinal microflora exhibiting similar antibiotic resistance patterns can confound such studies. Such was the case in a study by our group when attempting to characterize shedding patterns of O91:H21 in calves. A chromosomally integrated bioluminescence marker using a luxCDABE cassette from Photorhabdus luminescens was developed in O91:H21 to overcome such shortcomings of antibiotic resistance markers during animal challenge experiment. The marker was validated in various aspects and was shown to have no impact on metabolic reactions, isotype virulence gene patterns, cost to growth, and additionally demonstrated high in vitro stability. Together, the results indicated that a chromosomally integrated luxCDABE based marker may be a superior system for the study of STEC colonization and shedding in cattle.

  7. Radioimmunoscintigraphy of colorectal carcinoma using technetium-99m-labeled, totally human monoclonal antibody 88BV59H21-2.

    PubMed

    Gulec, S A; Serafini, A N; Moffat, F L; Vargas-Cuba, R D; Sfakianakis, G N; Franceschi, D; Crichton, V Z; Subramanian, R; Klein, J L; De Jager, R L

    1995-12-01

    Radioimmunoscintigraphy (RIS) using human monoclonal antibodies offers the important clinical advantage of repeated imaging over murine monoclonal antibodies by eliminating the cross-species antibody response. This article reports a Phase I-II clinical trial with Tc-99m-labeled, totally human monoclonal antibody 88BV59H21-2 in patients with colorectal carcinoma. The study population consisted of 34 patients with colorectal cancer (20 men and 14 women; age range, 44-81 years). Patients were administered 5-10 mg antibody labeled with 21-41 mCi Tc-99m by the i.v. route and imaged at 3-10 and 16-24 h after infusion using planar and single-photon emission computed tomographic (CT) techniques. Pathological confirmation was obtained in 25 patients who underwent surgery. Human antihuman antibody (HAHA) titers were checked prior to and 1 and 3 months after the infusion. RIS with Tc-99m-labeled 88BV59H21-2 revealed a better detection rate in the abdomen-pelvis region compared with axial CT. The combined use of both modalities increased the sensitivity in both the liver and abdomen-pelvis regions. Ten patients developed mild adverse reactions (chills and fever). No HAHA response was detected in this series. Tc-99m-labeled human monoclonal antibody 88BV59H21-2 RIS shows promise as a useful diagnostic modality in patients with colorectal cancer. RIS alone or in combination with CT is more sensitive than CT in detecting tumor within the abdomen and pelvis. Repeated RIS studies may be possible, due to the lack of a HAHA response.

  8. A new alpha-globin variant with increased oxygen affinity in a Swiss family: Hb Frauenfeld [alpha 138(H21)Ser-->Phe, TCC>TTC (alpha 2)].

    PubMed

    Hochuli, Michel; Zurbriggen, Karin; Schmid, Marlis; Speer, Oliver; Rochat, Philippe; Frauchiger, Beat; Kleinert, Peter; Schmugge, Markus; Troxler, Heinz

    2009-01-01

    A new alpha-globin mutation [alpha 138(H21)Ser-->Phe] was found in a 55-year-old male proband with an erythrocytosis known since his youth. Cation exchange high performance liquid chromatography (HPLC) revealed an additional peak eluting slightly before Hb A indicating the presence of a variant. The peak area of the variant was approximately one-third that of Hb A suggesting an alpha-globin variant. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry analysis confirmed the mutation at the protein level. The variant is also detectable with isoelectric focusing and reversed phase HPLC. DNA analysis revealed a heterozygous sequence mutation at codon 138 of the alpha2 gene. A C>T transition at the second nucleotide of the codon indicated a Ser-->Phe exchange. The variant showed increased oxygen affinity and was named Hb Frauenfeld.

  9. Apoptotic effect of novel Schiff Based CdCl2(C14H21N3O2) complex is mediated via activation of the mitochondrial pathway in colon cancer cells

    PubMed Central

    Hajrezaie, Maryam; Paydar, Mohammadjavad; Looi, Chung Yeng; Moghadamtousi, Soheil Zorofchian; Hassandarvish, Pouya; Salga, Muhammad Saleh; Karimian, Hamed; Shams, Keivan; Zahedifard, Maryam; Majid, Nazia Abdul; Ali, Hapipah Mohd; Abdulla, Mahmood Ameen

    2015-01-01

    The development of metal-based agents has had a tremendous role in the present progress in cancer chemotherapy. One well-known example of metal-based agents is Schiff based metal complexes, which hold great promise for cancer therapy. Based on the potential of Schiff based complexes for the induction of apoptosis, this study aimed to examine the cytotoxic and apoptotic activity of a CdCl2(C14H21N3O2) complex on HT-29 cells. The complex exerted a potent suppressive effect on HT-29 cells with an IC50 value of 2.57 ± 0.39 after 72 h of treatment. The collapse of the mitochondrial membrane potential and the elevated release of cytochrome c from the mitochondria to the cytosol indicate the involvement of the intrinsic pathway in the induction of apoptosis. The role of the mitochondria-dependent apoptotic pathway was further proved by the significant activation of the initiator caspase-9 and the executioner caspases-3 and -7. In addition, the activation of caspase-8, which is associated with the suppression of NF-κB translocation to the nucleus, also revealed the involvement of the extrinsic pathway in the induced apoptosis. The results suggest that the CdCl2(C14H21N3O2) complex is able to induce the apoptosis of colon cancer cells and is a potential candidate for future cancer studies. PMID:25764970

  10. C15H21RuSe

    NASA Astrophysics Data System (ADS)

    Mikhova, B. M.

    This document is part of Subvolume D5 `Chemical Shifts and Coupling Constants for Carbon-13. Part 5: Organometallic Compounds' of Volume 35 `Nuclear Magnetic Resonance Data' of Landolt-Börnstein Group III: `Condensed Matter'.

  11. Materials Data on Mg5AlH21O17 (SG:1) by Materials Project

    SciTech Connect

    Kristin Persson

    2014-07-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  12. Structure above the t1 / 2 = 6.85-h, 21/2+ isomer in 93Mo

    NASA Astrophysics Data System (ADS)

    Chiara, C. J.; Carroll, J. J.; Lane, G. J.; Hota, S. S.; Mitchell, A. J.; Palalani, N.; Reed, M. W.

    2016-03-01

    Excited states in 93Mo were populated in the 90Zr(7Li, p 3 n) reaction at the Heavy-Ion Accelerator Facility of the Australian National University. The CAESAR array of nine coaxial HPGe detectors and two low-energy photon spectrometers (LEPSs) was used to detect the emitted gamma rays. Relative yields for population of the 21/2+, 93mMo state and neighboring reaction channels were determined from gamma-singles data for beam energies of 5 to 8 MeV/ A. The level structure above the isomer has been expanded through gamma-gamma coincidence measurements. These results will be compared with high-spin structure of neighboring nuclei and with shell-model calculations. Supported in part by the U.S. Army Research Laboratory under Cooperative Agreement W911NF-12-2-0019.

  13. SPECIAL SESSION: (H21) on Global Precipitation Mission for Hydrology and Hydrometeorology. Sampling-Error Considerations for GPM-Era Rainfall Products

    NASA Technical Reports Server (NTRS)

    Bell, Thomas L.; Lau, William K. M. (Technical Monitor)

    2002-01-01

    The proposed Global Precipitation Mission (GPM) builds on the success of the Tropical Rainfall Measuring Mission (TRMM), offering a constellation of microwave-sensor-equipped smaller satellites in addition to a larger, multiply-instrumented "mother" satellite that will include an improved precipitation radar system to which the precipitation estimates of the smaller satellites can be tuned. Coverage by the satellites will be nearly global rather than being confined as TRMM was to lower latitudes. It is hoped that the satellite constellation can provide observations at most places on the earth at least once every three hours, though practical considerations may force some compromises. The GPM system offers the possibility of providing precipitation maps with much better time resolution than the monthly averages around which TRMM was planned, and therefore opens up new possibilities for hydrology and data assimilation into models. In this talk, methods that were developed for estimating sampling error in the rainfall averages that TRMM is providing will be used to estimate sampling error levels for GPM-era configurations. Possible impacts on GPM products of compromises in the sampling frequency will be discussed.

  14. Mass spectrometric characterization of conformational preludes to [beta]2-microglobulin aggregation

    NASA Astrophysics Data System (ADS)

    Jørgensen, Thomas J. D.; Cheng, Lei; Heegaard, Niels H. H.

    2007-12-01

    Characterization of protein folding and unfolding is an important issue for basic biological science, for understanding the devastating amyloid diseases, and for the manufacture and use of biological therapeutics. Unlike nuclear magnetic resonance spectroscopy, the use of mass spectrometry to monitor amide hydrogen (1H/2H) exchange kinetics (HX-MS) allows characterization of structural dynamics even when only limited amounts of protein is available. As an adjunct technique, requiring even less material and very well suited for serial monitoring of folding phenomena in a single solution under native conditions capillary electrophoresis may also be very informative. These approaches are here used to examine the small (99 amino acid residues) protein [beta]2-microglobulin ([beta]2m) which is prone to amyloidogenic unfolding especially after cleavage at its lysine-58 residue. The propensity for unfolding of native, non-cleaved [beta]2m and lysine-58 cleaved [beta]2m variants as well as the effect of acetonitrile on the conformational equilibria could be addressed by these approaches. At physiological conditions, intact [beta]2m and the lysine-58 cleaved variants undergo a transient unfolding that exhibit an EX1 type hydrogen exchange behaviour. We have measured the unfolding rate constants for the cleaved variant where Lys-58 is removed ([Delta]K58-[beta]2m) and the cleaved variant where this residue is preserved (cK58-[beta]2m) at various temperatures. Below 37 °C, the variant devoid of Lys-58 ([Delta]K58-[beta]2m) has a higher unfolding rate than cK58-[beta]2m and this correlates with the observation that [Delta]K58-[beta]2m has a higher propensity to aggregate. The results of our studies provide valuable insight into the early conformational perturbations involved in rendering this protein insoluble and amyloidogenic. The approaches used in this study should be useful also for the characterization of other conformationally unstable proteins.

  15. Genetic diversity and virulence potential of Shiga-toxigenic Escherichia coli strains of O113 serogroup isolated from ground beef in the U.S.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: An adherence factor such as intimin is often required for Shiga toxigenic E. coli (STEC) to cause severe diseases. O113:H21 strains do not produce intimin, but have caused HUS in Australia. Analysis of over 4000 ground beef samples in the U.S. found O113:H21 to be the serotype most ...

  16. A novel chalcone derivative attenuates the diabetes-induced renal injury via inhibition of high glucose-mediated inflammatory response and macrophage infiltration

    SciTech Connect

    Fang, Qilu; Zhao, Leping; Wang, Yi; Zhang, Yali; Li, Zhaoyu; Pan, Yong; Kanchana, Karvannan; Wang, Jingying; Tong, Chao; Li, Dan; Liang, Guang

    2015-01-15

    Inflammation plays a central role in the development and progression of diabetic nephropathy (DN). Researches on novel anti-inflammatory agents may offer new opportunities for the treatment of DN. We previously found a chalcone derivative L6H21 could inhibit LPS-induced cytokine release from macrophages. The aim of this study was to investigate whether L6H21 could ameliorate the high glucose-mediated inflammation in NRK-52E cells and attenuate the inflammation-mediated renal injury. According to the results, L6H21 showed a great inhibitory effect on the expression of pro-inflammatory cytokines, cell adhesion molecules, chemokines, and macrophage adhesion via down-regulation of NF-κB/MAPKs activity in high glucose-stimulated renal NRK-52E cells. Further, in vivo oral administration with L6H21 at a dosage of 20 mg/kg/2 days showed a decreased expression of pro-inflammatory cytokines, cell adhesion molecules, which subsequently contributed to the inhibition on renal macrophage infiltration, the reduction of serum creatinine and BUN levels, and the improvement on the fibrosis and pathological changes in the renal tissues of diabetic mice. These findings provided that chalcone derived L6H21 may be a promising anti-inflammatory agent and have the potential in the therapy of diabetic nephropathy, and importantly, MAPK/NF-κB signaling system may be a novel therapeutic target for human DN in the future. - Highlights: • Inflammation plays a central role in the development of diabetic nephropathy. • Compound L6H21 reduced the high glucose-mediated inflammation in NRK-52E cells. • Compound L6H21 attenuated the inflammation-mediated renal injury. • L6H21 exhibited anti-inflammatory effects via inactivation of NF-κB/MAPKs. • MAPKs/NF-κB may be a novel therapeutic target in diabetic nephropathy treatment.

  17. Electrostatic properties of cytochrome f: implications for docking with plastocyanin.

    PubMed Central

    Pearson, D C; Gross, E L; David, E S

    1996-01-01

    The electrostatic properties of cytochrome f (cyt f), a member of the cytochrome b6f complex and reaction partner with plastocyanin (PC) in photosynthetic electron transport, are qualitatively studied with the goal of determining the mechanism of electron transfer between cyt f and PC. A crystal structure for cyt f was analyzed with the software package GRASP, revealing a large region of positive potential generated by a patch of positively charged residues (including K58, K65, K66, K122, K185, K187, and R209) and reinforced by the iron center of the heme. This positive field attracts the negative charges of the two acidic patches on the mobile electron carrier PC. Three docked complexes are obtained for the two proteins, based on electrostatic or hydrophobic interactions or both and on steric fits by manual docking methods. The first of these three complexes shows strong electrostatic interactions between K187 on cyt f and D44 on PC and between E59 on PC and K58 on cyt f. Two other manually docked complexes are proposed, implicating H87 on PC as the electron-accepting site from the iron center of cyt f through Y1. The second complex maintains the D44/K187 cross-link (but not the E59/K58 link) while increasing hydrophobic interactions between PC and cyt f. Hydrophobic interactions are increased still further in the third complex, whereas the link between K187 on cyt f and D44 on PC is broken. The proposed reaction mechanism, therefore, involves an initial electrostatic docking complex that gives rise to a nonpolar attraction between the regions surrounding H87 on PC and Y1 on cyt f, providing for an electron-transfer active complex. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 PMID:8804589

  18. Increased Acid Stability of the Hemagglutinin Protein Enhances H5N1 Influenza Virus Growth in the Upper Respiratory Tract but Is Insufficient for Transmission in Ferrets

    PubMed Central

    Zaraket, Hassan; Bridges, Olga A.; Duan, Susu; Baranovich, Tatiana; Yoon, Sun-Woo; Reed, Mark L.; Salomon, Rachelle; Webby, Richard J.; Webster, Robert G.

    2013-01-01

    Influenza virus entry is mediated by the acidic-pH-induced activation of hemagglutinin (HA) protein. Here, we investigated how a decrease in the HA activation pH (an increase in acid stability) influences the properties of highly pathogenic H5N1 influenza virus in mammalian hosts. We generated isogenic A/Vietnam/1203/2004 (H5N1) (VN1203) viruses containing either wild-type HA protein (activation pH 6.0) or an HA2-K58I point mutation (K to I at position 58) (activation pH 5.5). The VN1203-HA2-K58I virus had replication kinetics similar to those of wild-type VN1203 in MDCK and normal human bronchial epithelial cells and yet had reduced growth in human alveolar A549 cells, which were found to have a higher endosomal pH than MDCK cells. Wild-type and HA2-K58I viruses promoted similar levels of morbidity and mortality in C57BL/6J mice and ferrets, and neither virus transmitted efficiently to naive contact cage-mate ferrets. The acid-stabilizing HA2-K58I mutation, which diminishes H5N1 replication and transmission in ducks, increased the virus load in the ferret nasal cavity early during infection while simultaneously reducing the virus load in the lungs. Overall, a single, acid-stabilizing mutation was found to enhance the growth of an H5N1 influenza virus in the mammalian upper respiratory tract, and yet it was insufficient to enable contact transmission in ferrets in the absence of additional mutations that confer α(2,6) receptor binding specificity and remove a critical N-linked glycosylation site. The information provided here on the contribution of HA acid stability to H5N1 influenza virus fitness and transmissibility in mammals in the background of a non-laboratory-adapted virus provides essential information for the surveillance and assessment of the pandemic potential of currently circulating H5N1 viruses. PMID:23824818

  19. Molecular and stable carbon isotopic compositions of hopanoids in seep carbonates from the South China Sea continental slope

    NASA Astrophysics Data System (ADS)

    Guan, Hongxiang; Sun, Yongge; Mao, Shengyi; Zhu, Xiaowei; Wu, Nengyou

    2014-10-01

    The lipid biomarkers of hopanoids in cold seep carbonates from the South China Sea continental slope were investigated by gas chromatography-mass spectrometer (GC-MS) and gas chromatography-isotope ratio-mass spectrometer (GC-ir-MS). The distribution of hopanes/hopenes shows a preference for the ‘biological’ 17β(H), 21β(H)-over the ‘geological’ 17α(H), 21β(H)-configuration. This interpretation is in agreement with the strong odd-even preference of long-chain n-alkanes in those samples, suggesting that the ββ hopanes may be the early diagenetic products of biohopanoids and the αβ, βα configurations of hopanes were mainly derived from allochthonous sources contributing to the organic matter of the carbonates. In terms of hopanoid acids, the C30 to C33 17β(H), 21β(H)-hopanoid acids were detected with C32 17β(H), 21β(H)-hopanoid acid being the most abundant. However, there is a significant difference in stable carbon isotopic compostions of the C32 17β(H), 21β(H)-hopanoic acid among samples (-30.7‰ to -69.8‰). The δ13C values match well with the carbon isotopic compositions of SRB-derived iso-/anteiso-C15:0 fatty acids in the samples, which strongly depend on the carbon utilization types by microbe. The most abundant compound of hopanols detected in the samples, C30-17β(H), 21β(H)-hopanol, may be a good indicator of diagenetic product of type I methanotrophs. The molecular and carbon isotopic compositions of hopanoids demonstrate clearly that there is a combination contribution of both SRB and type I or type X methanotrophs to the source organism in the seep carbonates from the South China Sea continental slope.

  20. Recurrent Hemolytic and Uremic Syndrome Induced by Escherichia Coli

    PubMed Central

    Commereuc, Morgane; Weill, Francois-Xavier; Loukiadis, Estelle; Gouali, Malika; Gleizal, Audrey; Kormann, Raphaël; Ridel, Christophe; Frémeaux-Bacchi, Véronique; Rondeau, Eric; Hertig, Alexandre

    2016-01-01

    Abstract A widespread belief is that typical hemolytic and uremic syndrome (HUS) does not recur. We report the case of a patient infected twice with raw milk taken from his own cow and containing a Shiga toxin–producing Escherichia coli O174:H21 that induced recurrent HUS causing severe renal and cerebral disorders. A genomic comparison of the human and bovine Shiga toxin–producing Escherichia coli O174:H21 isolates revealed that they were identical. Typical HUS may recur. Since milk from this animal was occasionally distributed locally, thereby posing a serious threat for the whole village, this particular cow was destroyed. PMID:26735524

  1. Influence of acid-soluble proteins from bivalve Siliqua radiata ligaments on calcium carbonate crystal growth

    NASA Astrophysics Data System (ADS)

    Huang, Zeng-Qiong; Zhang, Gang-Sheng

    2016-08-01

    In vitro biomimetic synthesis of calcium carbonate (CaCO3) in the presence of shell proteins is a heavily researched topic in biomineralization. However, little is known regarding the function of bivalve ligament proteins in the growth of CaCO3 crystals. In this study, using fibrous protein K58 from Siliqua radiata ligaments or coverslips as substrates, we report the results of our study of CaCO3 precipitation in the presence or absence of acid-soluble proteins (ASP) from inner ligament layers. ASP can disturb the controlling function of K58 or a coverslip on the crystalline phase, resulting in the formation of aragonite, calcite, and vaterite. In addition, we identified the following four primary components from ASP by mass spectroscopy: alkaline phosphatase (ALP), ABC transporter, keratin type II cytoskeletal 1 (KRT 1), and phosphate ABC transporter, phosphate-binding protein (PstS). Further analysis revealed that the first three proteins and especially ALP, which is important in bone mineralisation, could affect the polymorphism and morphology of CaCO3 crystals by trapping calcium ions in their domains. Our results indicate that ALP may play an important role in the formation of aragonite in S. radiata ligaments. This paper may facilitate our understanding of the biomineralization process.

  2. (9E)-9-benzylidene-2-methylsulfanyl-5-phenyl-6,7,8,9-tetrahydropyrimido[4,5-b]quinolin-4(3H)-one: a hydrogen-bonded R2(2)(8) dimer.

    PubMed

    Becerra, Diana; Insuasty, Braulio; Cobo, Justo; Glidewell, Christopher

    2013-12-15

    In the molecule of the title compound, C25H21N3OS, which was prepared by mild oxidation of the corresponding 5,6,7,8,9,10-hexahydro analogue, the fused carbocyclic ring adopts an envelope conformation. Pairs of molecules are linked into cyclic centrosymmetric dimers by pairs of inversion-related N-H···O hydrogen bonds.

  3. 1,5,6-Triphenyl-8-oxa-7-selena-6-phos-phabicyclo-[3.2.1]octane-6-selone.

    PubMed

    Hua, Guoxiong; Li, Yang; Slawin, Alexandra M Z; Woollins, J Derek

    2007-12-06

    The structure of the title compound, C(23)H(21)OPSe(2), consists of fused puckered five- and six-membered rings, PSeC(2)O and C(5)O, respectively, with a C(2)O bridgehead. The C(5)O ring adopts a chair conformation, whilst the C(2)PSeO ring has an envelope conformation.

  4. Ethyl 3-(4-chloro-phen-yl)-2-phenyl-3-(4-phenyl-1,2,3-selena-diazol-5-yl)propano-ate.

    PubMed

    Sugumar, P; Sankari, S; Manisankar, P; Thiruselvam, V; Ponnuswamy, M N

    2013-01-01

    In the title compound, C25H21ClN2O2Se, the selena-diazole ring is almost planar [maximum deviation = 0.004 (2) Å], and the adjacent benzene ring is twisted by 50.6 (1)° with respect to this ring.

  5. Extended hopane derivatives in sediments - Identification by H-1 NMR

    NASA Technical Reports Server (NTRS)

    Taylor, J.; Wardroper, A. M. K.; Maxwell, J. R.

    1980-01-01

    Sedimentary C32 hopanoic acid, one of the most abundant in nature and of probable bacterial origin, has been isolated for the first time as a single component and characterized by H-1 NMR. The 17 alpha H, 21 beta H configuration of the C31 alkane has been similarly confirmed.

  6. 27 CFR 21.49 - Formula No. 23-H.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Formula No. 23-H. 21.49 Section 21.49 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specially Denatured Spirits Formulas and Authorized Uses § 21.49 Formula No....

  7. The 24-cell and Calabi-Yau threefolds with Hodge numbers (1,1)

    NASA Astrophysics Data System (ADS)

    Braun, Volker

    2012-05-01

    Calabi-Yau threefolds with h 11( X) = h 21( X) = 1 are constructed as free quotients of a hypersurface in the ambient toric variety defined by the 24-cell. Their fundamental groups are SL(2, 3), {{Z}_{{3}}} rtimes {{Z}_{{8}}} , and {Z}{3} × {{Q8}}.

  8. Tri-p-tolyl­phosphine

    PubMed Central

    Wang, Hao; Wang, Yi-Bin; Liu, Bo-Nian; Tang, Shi-Gui; Wei, Ping

    2008-01-01

    In the title compound C21H21P, the P atom is situated on a crystallographic threefold rotatory-inversion axis, resulting in threefold rotation symmetry of the title compound. The dihedral angles between the symmetry-related benzene rings are 87.40 (18)°. PMID:21201763

  9. 27 CFR 21.49 - Formula No. 23-H.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Formula No. 23-H. 21.49 Section 21.49 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... and Authorized Uses § 21.49 Formula No. 23-H. (a) Formula. To every 100 gallons of alcohol add:...

  10. Physical Diversity of Near-Earth Asteroids from Arecibo Radar Observations

    NASA Astrophysics Data System (ADS)

    Taylor, Patrick A.; Howell, Ellen S.; Nolan, Michael C.; Richardson, James E.; Springmann, Alessondra

    2015-08-01

    Radar observations of near-Earth asteroids have revealed a heterogeneous population with diameters spanning meter to kilometer scales, diverse shapes ranging from simple spheroids to extremely irregular bodies, rotation periods stretching from minutes to weeks, and a spectrum of surface properties. Since 1998, the Arecibo Observatory S-band radar system has detected over 400 near-Earth asteroids. We find the radar-observed near-Earth asteroid population with absolute magnitude H < 21 is not dominated by a single category of basic shape: spheroids, multiple-asteroid systems, double-lobed contact binaries, elongated bodies, or irregularly shaped asteroids. A radar-observed binary fraction of 14% (N = 38; including two triple-asteroid systems) among near-Earth asteroids with H < 21 is in agreement with optical observations, while contact binaries account for a similar fraction (14%; N = 38). At smaller sizes, binaries and contact binaries are much rarer, with only three binaries and one contact binary with H < 21 detected thus far. The spin distribution of near-Earth asteroids estimated from radar matches very well with the spin distribution determined from optical lightcurves, including the well-known spin barrier for bodies with H < 21 and the curious lack of small, slowly rotating bodies with H > 21, despite different biases in these observing techniques. The shape and spin distributions of near-Earth asteroids observed with radar both show a distinct change in the population around H of 21 or 22 (100- to 200-m diameters), possibly indicating fundamental structural changes at this scale. Beyond constraining overall sizes and shapes, radar images as fine as 7.5-m resolution with Arecibo, akin to a low-cost flyby, reveal asteroid surfaces with ridges, concavities, crater-like depressions, angular facets, and boulders, details that constrain regolith properties and affect our understanding of geophysics in microgravity. Furthermore, the integrated surface properties

  11. Shiga Toxin, Cytolethal Distending Toxin, and Hemolysin Repertoires in Clinical Escherichia coli O91 Isolates▿

    PubMed Central

    Bielaszewska, Martina; Stoewe, Franziska; Fruth, Angelika; Zhang, Wenlan; Prager, Rita; Brockmeyer, Jens; Mellmann, Alexander; Karch, Helge; Friedrich, Alexander W.

    2009-01-01

    Shiga toxin (Stx)-producing Escherichia coli (STEC) strains of serogroup O91 are the most common human pathogenic eae-negative STEC strains. To facilitate diagnosis and subtyping of these pathogens, we genotypically and phenotypically characterized 100 clinical STEC O91 isolates. Motile strains expressed flagellar antigens H8 (1 strain), H10 (2 strains), H14 (52 strains), and H21 (20 strains) or were H nontypeable (Hnt) (10 strains); 15 strains were nonmotile. All nonmotile and Hnt strains possessed the fliC gene encoding the flagellin subunit of the H14 antigen (fliCH14). Most STEC O91 strains possessed enterohemorrhagic E. coli hlyA and expressed an enterohemolytic phenotype. Among seven stx alleles identified, stx2dact, encoding mucus- and elastase-activatable Stx2d, was present solely in STEC O91:H21, whereas most strains of the other serotypes possessed stx1. Moreover, only STEC O91:H21 possessed the cdt-V cluster, encoding cytolethal distending toxin V; the toxin was regularly expressed and was lethal to human microvascular endothelial cells. Infection with STEC O91:H21 was associated with hemolytic-uremic syndrome (P = 0.0015), whereas strains of the other serotypes originated mostly in patients with nonbloody diarrhea. We conclude that STEC O91 clinical isolates belong to at least four lineages that differ by H antigens/fliC types, stx genotypes, and non-stx putative virulence factors, with accumulation of virulence determinants in the O91:H21 lineage. Isolation of STEC O91 from patients' stools on enterohemolysin agar and the rapid initial subtyping of these isolates using fliC genotyping facilitate the identification of these emerging pathogens in clinical and epidemiological studies and enable prediction of the risk of a severe clinical outcome. PMID:19403777

  12. Angular Momentum and Topological Dependence of Kepler's Third Law in the Broucke-Hadjidemetriou-Hénon Family of Periodic Three-Body Orbits

    NASA Astrophysics Data System (ADS)

    Janković, Marija R.; Dmitrašinović, V.

    2016-02-01

    We use 57 recently found topological satellites of Broucke-Hadjidemetriou-Hénon's periodic orbits with values of the topological exponent k ranging from k =3 to k =58 to plot the angular momentum L as a function of the period T , with both L and T rescaled to energy E =-0.5 . Upon plotting L (T /k ) we find that all our solutions fall on a curve that is virtually indiscernible by the naked eye from the L (T ) curve for nonsatellite solutions. The standard deviation of the satellite data from the sixth-order polynomial fit to the progenitor data is σ =0.13 . This regularity supports Hénon's 1976 conjecture that the linearly stable Broucke-Hadjidemetriou-Hénon orbits are also perpetually, or Kol'mogorov-Arnol'd-Moser, stable.

  13. Angular Momentum and Topological Dependence of Kepler's Third Law in the Broucke-Hadjidemetriou-Hénon Family of Periodic Three-Body Orbits.

    PubMed

    Janković, Marija R; Dmitrašinović, V

    2016-02-12

    We use 57 recently found topological satellites of Broucke-Hadjidemetriou-Hénon's periodic orbits with values of the topological exponent k ranging from k=3 to k=58 to plot the angular momentum L as a function of the period T, with both L and T rescaled to energy E=-0.5. Upon plotting L(T/k) we find that all our solutions fall on a curve that is virtually indiscernible by the naked eye from the L(T) curve for nonsatellite solutions. The standard deviation of the satellite data from the sixth-order polynomial fit to the progenitor data is σ=0.13. This regularity supports Hénon's 1976 conjecture that the linearly stable Broucke-Hadjidemetriou-Hénon orbits are also perpetually, or Kol'mogorov-Arnol'd-Moser, stable.

  14. Sumoylation Inhibits the Growth Suppressive Properties of Ikaros.

    PubMed

    Apostolov, Apostol; Litim-Mecheri, Isma; Oravecz, Attila; Goepp, Marie; Kirstetter, Peggy; Marchal, Patricia; Ittel, Antoine; Mauvieux, Laurent; Chan, Susan; Kastner, Philippe

    2016-01-01

    The Ikaros transcription factor is a tumor suppressor that is also important for lymphocyte development. How post-translational modifications influence Ikaros function remains partially understood. We show that Ikaros undergoes sumoylation in developing T cells that correspond to mono-, bi- or poly-sumoylation by SUMO1 and/or SUMO2/3 on three lysine residues (K58, K240 and K425). Sumoylation occurs in the nucleus and requires DNA binding by Ikaros. Sumoylated Ikaros is less effective than unsumoylated forms at inhibiting the expansion of murine leukemic cells, and Ikaros sumoylation is abundant in human B-cell acute lymphoblastic leukemic cells, but not in healthy peripheral blood leukocytes. Our results suggest that sumoylation may be important in modulating the tumor suppressor function of Ikaros.

  15. Sumoylation Inhibits the Growth Suppressive Properties of Ikaros

    PubMed Central

    Goepp, Marie; Kirstetter, Peggy; Marchal, Patricia; Ittel, Antoine; Mauvieux, Laurent; Chan, Susan; Kastner, Philippe

    2016-01-01

    The Ikaros transcription factor is a tumor suppressor that is also important for lymphocyte development. How post-translational modifications influence Ikaros function remains partially understood. We show that Ikaros undergoes sumoylation in developing T cells that correspond to mono-, bi- or poly-sumoylation by SUMO1 and/or SUMO2/3 on three lysine residues (K58, K240 and K425). Sumoylation occurs in the nucleus and requires DNA binding by Ikaros. Sumoylated Ikaros is less effective than unsumoylated forms at inhibiting the expansion of murine leukemic cells, and Ikaros sumoylation is abundant in human B-cell acute lymphoblastic leukemic cells, but not in healthy peripheral blood leukocytes. Our results suggest that sumoylation may be important in modulating the tumor suppressor function of Ikaros. PMID:27315244

  16. Far infrared and submillimeter brightness temperatures of the giant planets

    NASA Technical Reports Server (NTRS)

    Hildebrand, R. H.; Loewenstein, R. F.; Harper, D. A.; Orton, G. S.; Keene, J.; Whitcomb, S. E.

    1985-01-01

    The brightness temperatures of Jupiter, Saturn, Uranus, and Neptune in the range 35 to 1000 micron. The effective temperatures derived from the measurements, supplemented by shorter wavelength Voyager data for Jupiter and Saturn, are 126.8 + or - 4.5 K, 93.4 + or - 3.3 K, 58.3 + or - 2.0 K, and 60.3 + or - 2.0 K, respectively. The implications of the measurements for bolometric output and for atmospheric structure and composition are discussed. The temperature spectrum of Jupiter shows a strong peak at approx. 350 microns followed by a deep valley at approx. 450 to 500 microns. Spectra derived from model atmospheres qualitatively reproduced these features but do not fit the data closely.

  17. Angular Momentum and Topological Dependence of Kepler's Third Law in the Broucke-Hadjidemetriou-Hénon Family of Periodic Three-Body Orbits.

    PubMed

    Janković, Marija R; Dmitrašinović, V

    2016-02-12

    We use 57 recently found topological satellites of Broucke-Hadjidemetriou-Hénon's periodic orbits with values of the topological exponent k ranging from k=3 to k=58 to plot the angular momentum L as a function of the period T, with both L and T rescaled to energy E=-0.5. Upon plotting L(T/k) we find that all our solutions fall on a curve that is virtually indiscernible by the naked eye from the L(T) curve for nonsatellite solutions. The standard deviation of the satellite data from the sixth-order polynomial fit to the progenitor data is σ=0.13. This regularity supports Hénon's 1976 conjecture that the linearly stable Broucke-Hadjidemetriou-Hénon orbits are also perpetually, or Kol'mogorov-Arnol'd-Moser, stable. PMID:26918993

  18. Non-O157 verotoxin-producing Escherichia coli: a problem, paradox, and paradigm.

    PubMed

    Bettelheim, Karl A

    2003-04-01

    The problems associated with identification and characterization of non-O157 verotoxin-producing Escherichia coli (VTEC) are discussed. The paradox of VTEC is that most reports of human illnesses are associated with serotypes such as O157:H7, O111:H- (nonmotile), O26:H11, and O113:H21, which are rarely found in domestic animals. However, those VTEC serotypes commonly found in domestic animals, especially ruminants, rarely cause human illnesses. When they cause human illnesses, the symptoms are similar to those caused by the serotypes E. coli O157:H7, O111:H-, O26:H11, and O113:H21. The impact of VTEC on human and animal health is also addressed. The VTEC and their toxicity are considered as a paradigm for emerging pathogens. The question on how such pathogens could arise from a basic commensal population is also addressed.

  19. Steranes and triterpanes generated from kerogen pyrolysis in the absence and presence of minerals

    NASA Technical Reports Server (NTRS)

    Tannenbaum, E.; Ruth, E.; Kaplan, I. R.

    1986-01-01

    Changes in the degree of isomerization of steranes and triterpanes during kerogen pyrolysis in the absence or presence of minerals are described. Kerogen from a Monterey Formation diatomite core sample was pyrolyzed under reduced pressure at 300 C for 2-1000 hrs in the presence or absence of calcite, illite, and montmorillonite. It is observed that the extent of isomerization of biomakers in C-20 in 14 alpha(H), 17 alpha(H)-steranes, at C-22 in 17 alpha(H), 21 beta(H)-hopanes and of 17 beta(H), 21 beta(H)-hopanes correlates to early diagenetic stages in rock extracts from sedimentary basins, and faster isomerization for steranes and triterpanes in the bitumen then for those in the kerogen structure are detected. The effects of the minerals on the isomerization reactions are examined; calcite inhibits, and illite and montmorillonite catalyze the reactions.

  20. Invasion of epithelial cells by locus of enterocyte effacement-negative enterohemorrhagic Escherichia coli.

    PubMed

    Luck, Shelley N; Bennett-Wood, Vicki; Poon, Rachael; Robins-Browne, Roy M; Hartland, Elizabeth L

    2005-05-01

    The majority of enterohemorrhagic Escherichia coli (EHEC) strains associated with severe disease carry the locus of enterocyte effacement (LEE) pathogenicity island, which encodes the ability to induce attaching and effacing lesions on the host intestinal mucosa. While LEE is essential for colonization of the host in these pathogens, strains of EHEC that do not carry LEE are regularly isolated from patients with severe disease, although little is known about the way these organisms interact with the host epithelium. In this study, we compared the adherence properties of clinical isolates of LEE-negative EHEC with those of LEE-positive EHEC O157:H7. Transmission electron microscopy revealed that LEE-negative EHEC O113:H21 was internalized by Chinese hamster ovary (CHO-K1) epithelial cells and that intracellular bacteria were located within a membrane-bound vacuole. In contrast, EHEC O157:H7 remained extracellular and intimately attached to the epithelial cell surface. Quantitative gentamicin protection assays confirmed that EHEC O113:H21 was invasive and also showed that several other serogroups of LEE-negative EHEC were internalized by CHO-K1 cells. Invasion by EHEC O113:H21 was significantly reduced in the presence of the cytoskeletal inhibitors cytochalasin D and colchicine and the pan-Rho GTPase inhibitor compactin, whereas the tyrosine kinase inhibitor genistein had no significant impact on bacterial invasion. In addition, we found that EHEC O113:H21 was invasive for the human colonic cell lines HCT-8 and Caco-2. Overall these studies suggest that isolates of LEE-negative EHEC may employ a mechanism of host cell invasion to colonize the intestinal mucosa.

  1. Identification of a novel fimbrial gene cluster related to long polar fimbriae in locus of enterocyte effacement-negative strains of enterohemorrhagic Escherichia coli.

    PubMed

    Doughty, Stephen; Sloan, Joan; Bennett-Wood, Vicki; Robertson, Marcus; Robins-Browne, Roy M; Hartland, Elizabeth L

    2002-12-01

    Enterohemorrhagic Escherichia coli (EHEC) is a food-borne cause of bloody diarrhea and the hemolytic-uremic syndrome (HUS) in humans. Most strains of EHEC belong to a group of bacterial pathogens that cause distinctive lesions on the host intestine termed attaching-and-effacing (A/E) lesions. A/E strains of EHEC, including the predominant serotype, O157:H7, are responsible for the majority of HUS outbreaks worldwide. However, several serotypes of EHEC are not A/E pathogens because they lack the locus of enterocyte effacement (LEE) pathogenicity island. Nevertheless, such strains have been associated with sporadic cases and small outbreaks of hemorrhagic colitis and HUS. Of these LEE-negative organisms, O113:H21 is one of the most commonly isolated EHEC serotypes in many regions. Clinical isolates of LEE-negative EHEC typically express Shiga toxin 2 and carry an approximately 90-kb plasmid that encodes EHEC hemolysin, but in the absence of LEE, little is known about the way in which these pathogens colonize the host intestine. In this study we describe the identification of a novel fimbrial gene cluster related to long polar fimbriae in EHEC O113:H21. This chromosomal region comprises four open reading frames, lpfA to lfpD, and has the same location in the EHEC O113:H21 genome as O island 154 in the prototype EHEC O157:H7 strain, EDL933. In a survey of EHEC of other serotypes, homologues of lpfA(O113) were found in 26 of 28 LEE-negative and 8 of 11 non-O157:H7 LEE-positive EHEC strains. Deletion of the putative major fimbrial subunit gene, lpfA, from EHEC O113:H21 resulted in decreased adherence of this strain to epithelial cells, suggesting that lpf(O113) may function as an adhesin in LEE-negative isolates of EHEC.

  2. 2,2,6,6-Tetra­methyl­piperidinium triisopropoxysilanethiol­ate

    PubMed Central

    Baranowska, Katarzyna; Roman, Paweł; Socha, Justyna

    2009-01-01

    The crystal of the title compound, C9H20N+·C9H21O3SSi−, is built of aggregates, each made up of two 2,2,6,6-tetra­methyl­piperidinium cations and two triisopropoxysilanethiol­ate anions. The aggregates are linked by four N—H⋯S bonds and correspond to an R 2 4(8) graph-set motif. PMID:21578416

  3. N,N′-Dibenzyl-N′′-(2-chloro-2,2-difluoro­acet­yl)-N,N′-dimethyl­phospho­ric triamide

    PubMed Central

    Raissi Shabari, Akbar; Pourayoubi, Mehrdad; Saneei, Anahid

    2011-01-01

    In the title mol­ecule, C18H21ClF2N3O2P, the P=O and N—H groups are syn to each other. The P atom adopts a slightly distorted tetra­hedral environment and the N atoms of the tertiary amine groups are bonded in an essentially planar geometry. In the crystal, pairs of inter­molecular N—H⋯O(P) hydrogen bonds form centrosymmetric dimers. PMID:21522414

  4. Deacetyl tenuazonic acid p-toluene­sulfonyl­hydrazone

    PubMed Central

    Siegel, David; Blaske, Franziska; Koch, Matthias; Emmerling, Franziska; Nehls, Irene

    2009-01-01

    The title compound {systematic name: 4-methyl-N′-[(3E)-2-(1-methyl­prop­yl)-5-oxopyrrolidin-3-yl­idene]benzene­sulfono­hydrazide}, C15H21N3O3S, is the condensation product of deacetyl tenuazonic acid (DTA) and p-toluene­sulfonohydrazide. The crystal structure consists of chains along [100] linked by N—H⋯O hydrogen bonds. PMID:21578857

  5. (-)-crebanine.

    PubMed

    Duangthongyou, Tanwawan; Makarasen, Arthit; Techasakul, Supanna; Chimnoi, Nitirat; Siripaisarnpipat, Sutatip

    2011-01-01

    THE ASYMMETRIC UNIT OF THE TITLE COMPOUND [SYSTEMATIC NAME: 9,10-dimeth-oxy-7-methyl-6,7,7a,8-tetra-hydro-5H-benzo[g][1,3]benzodioxolo[6,5,4-de]quinoline], C(20)H(21)NO(4), contains two independent mol-ecules with very similar bond lengths and angles. The crystal packing exhibits voids of 131 Å(3). PMID:21523075

  6. Napropamide.

    PubMed

    Cho, Seonghwa; Kim, Jineun; Jeon, Youngeun; Kim, Tae Ho

    2013-01-01

    THE TITLE COMPOUND [SYSTEMATIC NAME: N,N-diethyl-2-(naphthalen-1-yl-oxy)propanamide], C17H21NO2, crystallizes with two independent mol-ecules in the asymmetric unit in which the dihedral angles between the naphthalene ring systems and the amide groups are 88.1 (9) and 88.7 (3)°. Four C-H⋯O hydrogen bonds stabilize the crystal structure. PMID:24109304

  7. Napropamide

    PubMed Central

    Cho, Seonghwa; Kim, Jineun; Jeon, Youngeun; Kim, Tae Ho

    2013-01-01

    The title compound [systematic name: N,N-diethyl-2-(naphthalen-1-yl­oxy)propanamide], C17H21NO2, crystallizes with two independent mol­ecules in the asymmetric unit in which the dihedral angles between the naphthalene ring systems and the amide groups are 88.1 (9) and 88.7 (3)°. Four C—H⋯O hydrogen bonds stabilize the crystal structure. PMID:24109304

  8. 1-Benzyl­piperidin-4-one O-(2-bromo­benz­yl)oxime

    PubMed Central

    Moreno-Fuquen, Rodolfo; Loaiza, Alix E.; Diaz-Velandia, John; Kennedy, Alan R.; Morrison, Catriona A.

    2012-01-01

    In the title mol­ecule, C19H21BrN2O, the piperidone ring adopts a chair conformation with a total puckering amplitude Q T of 0.554 (2) Å. The dihedral angle between the benzene rings is 64.10 (7)°. There are no significant inter­molecular inter­actions. PMID:23125804

  9. Comparative pathogenicity of Escherichia coli O157 and intimin-negative non-O157 Shiga toxin-producing E coli strains in neonatal pigs.

    PubMed

    Dean-Nystrom, Evelyn A; Melton-Celsa, Angela R; Pohlenz, Joachim F L; Moon, Harley W; O'Brien, Alison D

    2003-11-01

    We compared the pathogenicity of intimin-negative non-O157:H7 Shiga toxin (Stx)-producing Escherichia coli (STEC) O91:H21 and O104:H21 strains with the pathogenicity of intimin-positive O157:H7 and O157:H(-) strains in neonatal pigs. We also examined the role of Stx2d-activatable genes and the large hemolysin-encoding plasmid of O91:H21 strain B2F1 in the pathogenesis of STEC disease in pigs. We found that all E. coli strains that made wild-type levels of Stx caused systemic illness and histological lesions in the brain and intestinal crypts, whereas none of the control Stx-negative E. coli strains evoked comparable central nervous system signs or intestinal lesions. By contrast, the absence of intimin, hemolysin, or motility had little impact on the overall pathogenesis of systemic disease during STEC infection. The most striking differences between pigs inoculated with non-O157 STEC strains and pigs inoculated with O157 STEC strains were the absence of attaching and effacing intestinal lesions in pigs inoculated with non-O157:H7 strains and the apparent association between the level of Stx2d-activatable toxin produced by an STEC strain and the severity of lesions. PMID:14573674

  10. Influenza Hemagglutinin (HA) Stem Region Mutations That Stabilize or Destabilize the Structure of Multiple HA Subtypes

    PubMed Central

    Byrd-Leotis, Lauren; Galloway, Summer E.; Agbogu, Evangeline

    2015-01-01

    ABSTRACT Influenza A viruses enter host cells through endosomes, where acidification induces irreversible conformational changes of the viral hemagglutinin (HA) that drive the membrane fusion process. The prefusion conformation of the HA is metastable, and the pH of fusion can vary significantly among HA strains and subtypes. Furthermore, an accumulating body of evidence implicates HA stability properties as partial determinants of influenza host range, transmission phenotype, and pathogenic potential. Although previous studies have identified HA mutations that can affect HA stability, these have been limited to a small selection of HA strains and subtypes. Here we report a mutational analysis of HA stability utilizing a panel of expressed HAs representing a broad range of HA subtypes and strains, including avian representatives across the phylogenetic spectrum and several human strains. We focused on two highly conserved residues in the HA stem region: HA2 position 58, located at the membrane distal tip of the short helix of the hairpin loop structure, and HA2 position 112, located in the long helix in proximity to the fusion peptide. We demonstrate that a K58I mutation confers an acid-stable phenotype for nearly all HAs examined, whereas a D112G mutation consistently leads to elevated fusion pH. The results enhance our understanding of HA stability across multiple subtypes and provide an additional tool for risk assessment for circulating strains that may have other hallmarks of human adaptation. Furthermore, the K58I mutants, in particular, may be of interest for potential use in the development of vaccines with improved stability profiles. IMPORTANCE The influenza A hemagglutinin glycoprotein (HA) mediates the receptor binding and membrane fusion functions that are essential for virus entry into host cells. While receptor binding has long been recognized for its role in host species specificity and transmission, membrane fusion and associated properties of HA

  11. Molecular principles behind pyrazinamide resistance due to mutations in panD gene in Mycobacterium tuberculosis.

    PubMed

    Pandey, Bharati; Grover, Sonam; Tyagi, Chetna; Goyal, Sukriti; Jamal, Salma; Singh, Aditi; Kaur, Jagdeep; Grover, Abhinav

    2016-04-25

    The latest resurrection of drug resistance poses serious threat to the treatment and control of the disease. Mutations have been detected in panD gene in the Mycobacterium tuberculosis (Mtb) strains. Mutation of histidine to arginine at residue 21 (H21R) and isoleucine to valine at residue 29 (I49V) in the non-active site of panD gene has led to PZA resistance. This study will help in reconnoitering the mechanism of pyrazinamide (PZA) resistance caused due to double mutation identified in the panD gene of M. tuberculosis clinical isolates. It is known that panD gene encodes aspartate decarboxylase essential for β-alanine synthesis that makes it a potential therapeutic drug target for tuberculosis treatment. The knowledge about the molecular mechanism conferring drug resistance in M. tuberculosis is scarce, which is a significant challenge in designing successful therapeutic drug. In this study, structural and dynamic repercussions of H21R-I49V double mutation in panD complexed with PZA have been corroborated through docking and molecular dynamics based simulation. The double mutant (DM) shows low docking score and thus, low binding affinity for PZA as compared to the native protein. It was observed that the mutant protein exhibits more structural fluctuation at the ligand binding site in comparison to the native type. Furthermore, the flexibility and compactness analyses indicate that the double mutation influence interaction of PZA with the protein. The hydrogen-bond interaction patterns further supported our results. The covariance and PCA analysis elucidated that the double mutation affects the collective motion of residues in phase space. The results have been presented with an explanation for the induced drug resistance conferred by the H21R-I49V double mutation in panD gene and gain valuable insight to facilitate the advent of efficient therapeutics for combating resistance against PZA. PMID:26784657

  12. Verotoxin-producing Escherichia coli in Spain: prevalence, serotypes, and virulence genes of O157:H7 and non-O157 VTEC in ruminants, raw beef products, and humans.

    PubMed

    Blanco, Jorge; Blanco, Miguel; Blanco, Jesus E; Mora, Azucena; González, Enrique A; Bernárdez, Maria I; Alonso, Maria P; Coira, Amparo; Rodriguez, Asuncion; Rey, Joaquin; Alonso, Juan M; Usera, Miguel A

    2003-04-01

    In Spain, as in many other countries, verotoxin-producing Escherichia coli (VTEC) strains have been frequently isolated from cattle, sheep, and foods. VTEC strains have caused seven outbreaks in Spain (six caused by E. coli O157:H7 and one by E. coli O111:H- [nonmotile]) in recent years. An analysis of the serotypes indicated serological diversity. Among the strains isolated from humans, serotypes O26:H11, O111:H-, and O157:H7 were found to be more prevalent. The most frequently detected serotypes in cattle were O20:H19, O22:H8, O26:H11, O77:H41, O105:H18, O113:H21, O157:H7, O171:H2, and OUT (O untypeable):H19. Different VTEC serotypes (e.g., O5:H-, O6:H10, O91:H-, O117:H-, O128:H-, O128:H2, O146:H8, O146:H21, O156:H-, and OUT:H21) were found more frequently in sheep. These observations suggest a host serotype specificity for some VTEC. Numerous bovine and ovine VTEC serotypes detected in Spain were associated with human illnesses, confirming that ruminants are important reservoirs of pathogenic VTEC. VTEC can produce one or two toxins (VT1 and VT2) that cause human illnesses. These toxins are different proteins encoded by different genes. Another virulence factor expressed by VTEC is the protein intimin that is responsible for intimate attachment of VTEC and effacing lesions in the intestinal mucosa. This virulence factor is encoded by the chromosomal gene eae. The eae gene was found at a much less frequency in bovine (17%) and ovine (5%) than in human (45%) non-O157 VTEC strains. This may support the evidence that the eae gene contributes significantly to the virulence of human VTEC strains and that many animal non-O157 VTEC strains are less pathogenic to humans.

  13. Molecular principles behind pyrazinamide resistance due to mutations in panD gene in Mycobacterium tuberculosis.

    PubMed

    Pandey, Bharati; Grover, Sonam; Tyagi, Chetna; Goyal, Sukriti; Jamal, Salma; Singh, Aditi; Kaur, Jagdeep; Grover, Abhinav

    2016-04-25

    The latest resurrection of drug resistance poses serious threat to the treatment and control of the disease. Mutations have been detected in panD gene in the Mycobacterium tuberculosis (Mtb) strains. Mutation of histidine to arginine at residue 21 (H21R) and isoleucine to valine at residue 29 (I49V) in the non-active site of panD gene has led to PZA resistance. This study will help in reconnoitering the mechanism of pyrazinamide (PZA) resistance caused due to double mutation identified in the panD gene of M. tuberculosis clinical isolates. It is known that panD gene encodes aspartate decarboxylase essential for β-alanine synthesis that makes it a potential therapeutic drug target for tuberculosis treatment. The knowledge about the molecular mechanism conferring drug resistance in M. tuberculosis is scarce, which is a significant challenge in designing successful therapeutic drug. In this study, structural and dynamic repercussions of H21R-I49V double mutation in panD complexed with PZA have been corroborated through docking and molecular dynamics based simulation. The double mutant (DM) shows low docking score and thus, low binding affinity for PZA as compared to the native protein. It was observed that the mutant protein exhibits more structural fluctuation at the ligand binding site in comparison to the native type. Furthermore, the flexibility and compactness analyses indicate that the double mutation influence interaction of PZA with the protein. The hydrogen-bond interaction patterns further supported our results. The covariance and PCA analysis elucidated that the double mutation affects the collective motion of residues in phase space. The results have been presented with an explanation for the induced drug resistance conferred by the H21R-I49V double mutation in panD gene and gain valuable insight to facilitate the advent of efficient therapeutics for combating resistance against PZA.

  14. Verotoxin-producing Escherichia coli in Spain: prevalence, serotypes, and virulence genes of O157:H7 and non-O157 VTEC in ruminants, raw beef products, and humans.

    PubMed

    Blanco, Jorge; Blanco, Miguel; Blanco, Jesus E; Mora, Azucena; González, Enrique A; Bernárdez, Maria I; Alonso, Maria P; Coira, Amparo; Rodriguez, Asuncion; Rey, Joaquin; Alonso, Juan M; Usera, Miguel A

    2003-04-01

    In Spain, as in many other countries, verotoxin-producing Escherichia coli (VTEC) strains have been frequently isolated from cattle, sheep, and foods. VTEC strains have caused seven outbreaks in Spain (six caused by E. coli O157:H7 and one by E. coli O111:H- [nonmotile]) in recent years. An analysis of the serotypes indicated serological diversity. Among the strains isolated from humans, serotypes O26:H11, O111:H-, and O157:H7 were found to be more prevalent. The most frequently detected serotypes in cattle were O20:H19, O22:H8, O26:H11, O77:H41, O105:H18, O113:H21, O157:H7, O171:H2, and OUT (O untypeable):H19. Different VTEC serotypes (e.g., O5:H-, O6:H10, O91:H-, O117:H-, O128:H-, O128:H2, O146:H8, O146:H21, O156:H-, and OUT:H21) were found more frequently in sheep. These observations suggest a host serotype specificity for some VTEC. Numerous bovine and ovine VTEC serotypes detected in Spain were associated with human illnesses, confirming that ruminants are important reservoirs of pathogenic VTEC. VTEC can produce one or two toxins (VT1 and VT2) that cause human illnesses. These toxins are different proteins encoded by different genes. Another virulence factor expressed by VTEC is the protein intimin that is responsible for intimate attachment of VTEC and effacing lesions in the intestinal mucosa. This virulence factor is encoded by the chromosomal gene eae. The eae gene was found at a much less frequency in bovine (17%) and ovine (5%) than in human (45%) non-O157 VTEC strains. This may support the evidence that the eae gene contributes significantly to the virulence of human VTEC strains and that many animal non-O157 VTEC strains are less pathogenic to humans. PMID:12671177

  15. Virulence analysis of Hessian fly populations from Texas, Oklahoma, and Kansas.

    PubMed

    Chen, Ming-Shun; Echegaray, Erik; Whitworth, R Jeffrey; Wang, Haiyan; Sloderbeck, Phillip E; Knutson, Allen; Giles, Kristopher L; Royer, Tom A

    2009-04-01

    In recent years, the number of wheat, Triticum aestivum L., fields heavily infested by Hessian fly, Mayetiola destructor (Say), has increased in the Great Plains of the United States. Historically, resistance genes in wheat have been the most efficient means of controlling this insect pest. To determine which resistance genes are still effective in this area, virulence of six Hessian fly populations from Texas, Oklahoma, and Kansas was determined, using the resistance genes H3, H4, H5, H6, H7H8, H9, H10, H11, H12, H13, H16, H17, H18, H21, H22, H23, H24, H25, H26, H31, and Hdic. Five of the tested genes, H13, H21, H25, H26, and Hdic, conferred high levels of resistance (> 80% of plants scored resistant) to all tested populations. Resistance levels for other genes varied depending on which Hessian fly population they were tested against. Biotype composition analysis of insects collected directly from wheat fields in Grayson County, TX, revealed that the proportion of individuals within this population virulent to the major resistance genes was highly variable (89% for H6, 58% for H9, 28% for H5, 22% for H26, 15% for H3, 9% for H18, 4% for H21, and 0% for H13). Results also revealed that the percentages of biotypes virulent to specific resistance genes in a given population are highly correlated (r2 = 0.97) with the percentages of susceptible plants in a virulence test. This suggests that virulence assays, which require less time and effort, can be used to approximate biotype composition.

  16. (5,7-Dimethyl-2-oxo-2H-chromen-4-yl)methyl diethyl­dithio­carbamate

    PubMed Central

    Kumar, K. Mahesh; Devarajegowda, H. C.; Jeyaseelan, S; Mahabaleshwaraiah, N. M.; Kotresh, O.

    2012-01-01

    In the title compound, C17H21NO2S2, the coumarin ring system is nearly planar, with a maximum deviation of 0.080 (2) Å from the mean plane. An intra­molecular C—H⋯S hydrogen bond occurs. The crystal structure features C—H⋯S hydrogen bonds and weak π–π inter­actions with a centroid–centroid distance of 3.679 (1) Å. PMID:22719453

  17. Recent Results of Experiments with Radioactive 21Na and 7Be ion beams

    SciTech Connect

    Greife, U.; Livesay, Jake; Jewett, Cybele; Chipps, K.; Sarazin, F.; Bardayan, Daniel W; Blackmon, Jeff C; Nesaraja, Caroline D; Smith, Michael Scott; Champagne, A. E.; Fitzgerald, R. P.; Jones, K. L.; Thomas, J. S.; Kozub, R. L.

    2007-03-01

    We report here on experiments with radioactive 21Na and 7Be beams performed by Colorado School of Mines students at the ISAC facility of TRIUMF and the Holifield Radioactive Ion Beam Facility (HRIBF) of ORNL. At TRIUMF, the DRAGON recoil separator and its segmented BGO array were used to investigate higher energy resonances in the reaction H(21Na,gamma)22Mg. Using the HRIBF we performed an experiment with a 7Be ion beam to measure scattering off Hydrogen and Carbon. Both elastic 7Be + p scattering and for the first time resonant inelastic scattering 7Be(p,p0)7Be* were observed.

  18. Nuclear Astrophysics At ISAC With DRAGON

    SciTech Connect

    D'Auria, John M.

    2005-05-24

    The unique DRAGON (recoil mass separator) facility is now available to provide measurements of radiative capture reactions involving short-lived exotic reactants which are considered important in explosive stellar scenarios such as novae and X-ray bursts. A description of the first study completed, the 1H(21Na,22Mg){gamma} reaction, will be summarized and updated. In addition, the planned program for DRAGON will be presented along with a summary of the upgrade of the ISAC Radioactive Beams laboratory.

  19. Atpenins, new antifungal antibiotics produced by Penicillium sp. Production, isolation, physico-chemical and biological properties.

    PubMed

    Omura, S; Tomoda, H; Kimura, K; Zhen, D Z; Kumagai, H; Igarashi, K; Imamura, N; Takahashi, Y; Tanaka, Y; Iwai, Y

    1988-12-01

    Penicillium sp. FO-125, a soil isolate, was found to produce a new antifungal antibiotic complex named atpenin. Three components A4, A5 and B were isolated from the fermentation broth of the producing strain by solvent extraction, silica gel column chromatography and HPLC. The molecular formula of atpenins A4, A5 and B were determined to be C15H22NO5Cl, C15H21NO5Cl2 and C15H23NO5, respectively, on the basis of high resolution electron impact mass spectrometry and elemental analysis. They are active against filamentous fungi, especially, Trichophyton sp. PMID:3209470

  20. Crystal structure of 1-{4-hy-droxy-3-[(pyrrolidin-1-yl)meth-yl]phen-yl}-3-phenyl-prop-2-en-1-one.

    PubMed

    Aydın, Abdullah; Akkurt, Mehmet; Gul, Halise Inci; Yerdelen, Kadir Ozden; Celik, Raziye Catak

    2016-05-01

    In the title compound, C20H21NO2, the pyrrolidine ring adopts an envelope conformation with the N atom at the flap position. The central benzene ring makes dihedral angles of 21.39 (10) and 80.10 (15)° with the phenyl ring and the mean plane of the pyrrolidine ring, respectively. The mol-ecular conformation is stabilized by an intra-molecular O-H⋯N hydrogen bond, which closes an S(6) ring. A weak C-H⋯π inter-action is observed in the crystal. PMID:27308021

  1. (R)-[(R)-3-Benzyl-2-oxooxazolidin-4-yl][4-(methyl­sulfon­yl)phen­yl]methyl acetate

    PubMed Central

    Li, Feng; Zhao, Ming-Zhong; Jin, Chun-Hua; Zou, Jian-Wei

    2014-01-01

    The structure of the title compound, C20H21NO6S, is of inter­est with respect to its anti­bacterial properties. The oxazolidine ring makes dihedral angles of 79.63 (14) and 56.16 (12)° with the phenyl and benzene rings, respectively, while the phenyl and benzene rings make a dihedral angle of 64.37 (13)°. In the crystal, non-classical C—H⋯O hydrogen bonds link adjacent mol­ecules along the c axis. PMID:24860399

  2. Bis(μ-5-diisopropyl­amino-1,2,3,4-tetra­zolido-κ2 N 2:N 3)bis­[(triisopropyl­phosphane)copper(I)

    PubMed Central

    Kobrsi, Issam; Bassioni, Ghada

    2011-01-01

    In the binuclear centrosymmetric crystal structure of the title compound, [Cu2(C7H14N5)2(C9H21P)2], all atoms except those of the isopropyl groups are approximately co-planar. The Cu(II) atom is in a distorted trigonal–planar CuN2P coordination. Bond angles around the amino N atom suggest sp 2 hybridization. Several intra­molecular C—H⋯N inter­actions are present involving tetra­zolate N atoms. PMID:21836950

  3. Seropathotypes, Phylogroups, Stx subtypes, and intimin types of wildlife-carried, shiga toxin-producing escherichia coli strains with the same characteristics as human-pathogenic isolates.

    PubMed

    Mora, Azucena; López, Cecilia; Dhabi, Ghizlane; López-Beceiro, Ana M; Fidalgo, Luís E; Díaz, Eduardo A; Martínez-Carrasco, Carlos; Mamani, Rosalía; Herrera, Alexandra; Blanco, Jesús E; Blanco, Miguel; Blanco, Jorge

    2012-04-01

    The objectives of this study were to investigate the presence of Shiga toxin-producing Escherichia coli (STEC) strains in wildlife that have spread in Europe, living near human settlements; to analyze their epidemiological role in maintenance and transmission to domestic livestock; and to assess the potential health risk of wildlife-carried strains. STEC strains were recovered from 53% of roe deer, 8.4% of wild boars, and 1.9% of foxes sampled in the northwest of Spain (Galicia). Of the 40 serotypes identified, 21 were classified as seropathotypes associated with human disease, accounting for 81.5% of the wildlife-carried STEC strains, including the enterohemorrhagic serotypes O157:H7-D-eae-γ1, O26:[H11]-B1-eae-β1, O121:H19-B1-eae-ε1, and O145:[H28]-D-eae-γ1. None of the wildlife-carried strains belonged to the highly pathogenic serotype O104:H4-B1 from the recent Germany outbreak. Forty percent of wildlife-carried STEC strains shared serotypes, phylogroups, intimin types, and Stx profiles with isolates from human patients from the same geographic area. Furthermore, wildlife-carried strains belonging to serotypes O5:HNM-A, O26:[H11]-B1, O76:H19-B1, O145:[H28]-D, O146:H21-B1, and O157:H7-D showed pulsed-field gel electrophoresis (PFGE) profiles with >85% similarity to human-pathogenic STEC strains. We also found a high level of similarity among STEC strains of serotypes O5:HNM-A, O26:[H11]-B1, and O145:HNM-D of bovine (feces and beef) and wildlife origins. Interestingly, O146:H21-B1, the second most frequently detected serotype in this study, is commonly associated with human diarrhea and isolated from beef and vegetables sold in Galicia. Importantly, at least 3 STEC isolates from foxes (O5:HNM-A-eae-β1, O98:[H21]-B1-eae-ζ1, and O146:[H21]-B1) showed characteristics similar to those of human STEC strains. In conclusion, roe deer, wild boar, and fox in Galicia are confirmed to be carriers of STEC strains potentially pathogenic for humans and seem to play an

  4. Dichlorido[2-diphenyl­phosphanyl-N-(pyridin-3-ylmeth­yl)benzyl­idenamine-κ2 P,N]platinum(II)

    PubMed Central

    Chiririwa, Haleden; Meijboom, Reinout

    2011-01-01

    The title compound, [PtCl2(C25H21N2P)], is a PtII complex with an NPCl2 coordination sphere in which the metal is coordinated to the imino N and phosphane P atoms of the ligand and to two chloride ions. The PtII atom is in a distorted square-planar environment and is bound to the ligand via the P and amine N atoms in a cis fashion, with the chlorine atoms located at the two remaining sites. PMID:22219749

  5. 7-Chloro-5-(2-ethoxy-phen-yl)-1-methyl-3-propyl-2,6-dihydro-1H-pyrazolo[4,3-d]pyrimidine.

    PubMed

    Zhou, Ming-Qiu; Zhu, Kai; Lv, Xiao-Ping; Han, Ping-Fang; Wei, Ping

    2009-09-05

    In the title compound, C(17)H(21)ClN(4)O, the benzene ring is oriented at dihedral angles of 1.59 (3) and 1.27 (3)° with respect to the pyrimidine and pyrazole rings, while the dihedral angle between the pyrimidine and pyrazole rings is 0.83 (3)°. An intra-molecular N-H⋯O hydrogen bond results in the formation of a planar (r.m.s. deviation 0.004 Å) six-membered ring.

  6. 7-Chloro-5-(2-ethoxy­phen­yl)-1-methyl-3-propyl-2,6-dihydro-1H-pyrazolo[4,3-d]pyrimidine

    PubMed Central

    Zhou, Ming-Qiu; Zhu, Kai; Lv, Xiao-Ping; Han, Ping-Fang; Wei, Ping

    2009-01-01

    In the title compound, C17H21ClN4O, the benzene ring is oriented at dihedral angles of 1.59 (3) and 1.27 (3)° with respect to the pyrimidine and pyrazole rings, while the dihedral angle between the pyrimidine and pyrazole rings is 0.83 (3)°. An intra­molecular N—H⋯O hydrogen bond results in the formation of a planar (r.m.s. deviation 0.004 Å) six-membered ring. PMID:21577789

  7. X-Ray structure of a truncated form of cytochrome f from chlamydomonas Reinhardtii

    SciTech Connect

    Chi, Young-In; Huang, Li-Shar; Zhang, Zhaolei; Fernando-Velasquez, Javier G.; Berry, E. A.

    2000-03-01

    A truncated form of cytochrome f from Chlamydomonas Reinhardtii (an important eukaryotic model organism for photosynthetic electron transfer studies) has been crystallized (space group P212121; 3 molecules/ asymmetric unit) and its structure determined to 2.0 Angstrom by molecular replacement using the coordinates of a truncated turnip cytochrome f as a model. The structure displays the same folding and detailed features as turnip cytochrome f including: (a) an unusual heme Fe ligation by alpha-amino group of tyrosine 1, (b) a cluster of lysine residues (proposed docking site of plastocyanin), and (c) the presence of a chain of 7 water molecules bound to conserved residues and extending between the heme pocket and K58 and K66 at the lysine cluster. For this array of waters we propose a structural role. Two cytochrome f molecules are related by a non-crystallographic symmetry operator which is a distorted proper 2-fold rotation. This may represent the dimeric relation of the monomers in situ, however the heme orientation suggested by this model is not consistent with previous epr measurements on oriented membranes.

  8. Ubiquitination of the Dishevelled DIX domain blocks its head-to-tail polymerization

    PubMed Central

    Madrzak, Julia; Fiedler, Marc; Johnson, Christopher M.; Ewan, Richard; Knebel, Axel; Bienz, Mariann; Chin, Jason W.

    2015-01-01

    Dishevelled relays Wnt signals from the plasma membrane to different cytoplasmic effectors. Its signalling activity depends on its DIX domain, which undergoes head-to-tail polymerization to assemble signalosomes. The DIX domain is ubiquitinated in vivo at multiple lysines, which can be antagonized by various deubiquitinases (DUBs) including the CYLD tumour suppressor that attenuates Wnt signalling. Here, we generate milligram quantities of pure human Dvl2 DIX domain mono-ubiquitinated at two lysines (K54 and K58) by genetically encoded orthogonal protection with activated ligation (GOPAL), to investigate their effect on DIX polymerization. We show that the ubiquitination of DIX at K54 blocks its polymerization in solution, whereas DIX58-Ub remains oligomerization-competent. DUB profiling identified 28 DUBs that cleave DIX-ubiquitin conjugates, half of which prefer, or are specific for, DIX54-Ub, including Cezanne and CYLD. These DUBs thus have the potential to promote Dvl polymerization and signalosome formation, rather than antagonize it as previously thought for CYLD. PMID:25907794

  9. The Roles of Four Conserved Basic Amino Acids in a Ferredoxin-Dependent Cyanobacterial Nitrate Reductase

    PubMed Central

    Srivastava, Anurag P.; Hirasawa, Masakazu; Bhalla, Megha; Chung, Jung-Sung; Allen, James P.; Johnson, Michael K.; Tripathy, Jatindra N.; Rubio, Luis M.; Vaccaro, Brian; Subramanian, Sowmya; Flores, Enrique; Zabet-Moghaddam, Masoud; Stitle, Kyle; Knaff, David B.

    2013-01-01

    The roles of four conserved basic amino acids in the reaction catalyzed by the ferredoxin-dependent nitrate reductase from the cyanobacterium Synechococcus sp. PCC 7942 have been investigated using site-directed mutagenesis in combination with measurements of steady-state kinetics, substrate-binding affinities and spectroscopic properties of the enzyme’s two prosthetic groups. Replacement of either Lys58 or Arg70 by glutamine leads to a complete loss of activity, with both the physiological electron donor, reduced ferredoxin and with a non-physiological electron donor, reduced methyl viologen. More conservative, charge-maintaining K58R and R70K variants were also completely inactive. Replacement of Lys130 by glutamine produced a variant that retained 26% of the wild-type activity with methyl viologen as the electron donor and 22% of the wild-type activity with ferredoxin as the electron donor, while replacement by arginine produces a variant that retains a significantly higher percentage of the wild-type activity with both electron donors. In contrast, replacement of Arg146 by glutamine had minimal effect on the activity of the enzyme. These results, along with substrate-binding and spectroscopic measurements, are discussed in terms of an in silico structural model for the enzyme. PMID:23692082

  10. Development of The Viking Speech Scale to classify the speech of children with cerebral palsy.

    PubMed

    Pennington, Lindsay; Virella, Daniel; Mjøen, Tone; da Graça Andrada, Maria; Murray, Janice; Colver, Allan; Himmelmann, Kate; Rackauskaite, Gija; Greitane, Andra; Prasauskiene, Audrone; Andersen, Guro; de la Cruz, Javier

    2013-10-01

    Surveillance registers monitor the prevalence of cerebral palsy and the severity of resulting impairments across time and place. The motor disorders of cerebral palsy can affect children's speech production and limit their intelligibility. We describe the development of a scale to classify children's speech performance for use in cerebral palsy surveillance registers, and its reliability across raters and across time. Speech and language therapists, other healthcare professionals and parents classified the speech of 139 children with cerebral palsy (85 boys, 54 girls; mean age 6.03 years, SD 1.09) from observation and previous knowledge of the children. Another group of health professionals rated children's speech from information in their medical notes. With the exception of parents, raters reclassified children's speech at least four weeks after their initial classification. Raters were asked to rate how easy the scale was to use and how well the scale described the child's speech production using Likert scales. Inter-rater reliability was moderate to substantial (k>.58 for all comparisons). Test-retest reliability was substantial to almost perfect for all groups (k>.68). Over 74% of raters found the scale easy or very easy to use; 66% of parents and over 70% of health care professionals judged the scale to describe children's speech well or very well. We conclude that the Viking Speech Scale is a reliable tool to describe the speech performance of children with cerebral palsy, which can be applied through direct observation of children or through case note review.

  11. Coordination compounds of zinc(II) and N-alkylphenothiazines: synthesis and characterization

    NASA Astrophysics Data System (ADS)

    Gowda, Netkal M. Made; Pacquette, H. Lawrence; Kim, Doo-Hyung; Jayaram, Beby

    1996-08-01

    Zinc(II) chloride/acetate complexes of title ligands have been synthesized in {MeOH}/{water} medium. The compounds were characterized by their elemental analyses, molar conductivity, magnetic susceptibility, and spectroscopic data. The molecular formulas of the new complexes were found to be: [(C 17H 20ClN 2S) 4ZnCl 2]Cl 4 where C 17H 20ClN 2S = protonated chlorpromazine; [(C 19H 25N 2S) 2ZnCl 2]Cl 2 where C 19H 25N 2S = protonated ethopropazine; [(C 17H 21N 2S) 2ZnCl]Cl 3 where C 17H 21N 2S = protonated promethazine; [(C 21H 27N 2S 2) 2ZnCl 2]Cl 2 .MeOH and [(C 21H 27N 2S 2)ZnCl](OAc) 2 where C 21H 27N 2S 2 = protonated thioridazine; and [(C 21H 26F 3N 3S)ZnCl 3]Cl where C 21H 26F 3N 3S = diprotonated trifluoperazine. All compounds are diamagnetic and ionic in nature. Structures for the complexes are proposed.

  12. Neocuproine-extended porphyrin coordination complexes. 2. Spectroscopic properties of the metalloporphyrin derivatives and investigations into the HOMO ordering.

    PubMed

    Vannelli, T A; Karpishin, T B

    2000-01-24

    The synthesis of a porphyrin compound, 1, containing a 2,9-dimethyl-1,10-phenanthroline moiety that is fused at the beta-pyrrole positions is reported. The absorption spectra of the free-base, copper(II), and zinc(II) derivatives have been studied. On the basis of absorption band intensities, the HOMO of the free base (H21) and its copper and zinc complexes (Cu1 and Zn1) was determined to be of a1u symmetry. Relative to H21, compounds Cul and Znl show enhanced spectral changes upon external metal ion binding. Although the HOMO is the same in all three compounds, the energy gap between the two highest occupied orbitals is greater for Cu1 and Zn1 than it is for the free-base compound. Several metal ions (Ni2+, Cu+, Cu2+, Zn2+, Li+) were examined in their binding to the phenanthrolinic group by measuring the resulting changes in the absorption spectra. It is shown that the observed changes in the absorption spectra are insensitive to the nature of the metal ion coordinated by the phenanthroline moiety. Significant differences in the absorption and emission spectra between Zn1 and [Zn(Zn1)2]2+ clearly demonstrate that the porphyrin pi-system is strongly affected by the binding of metal ions at the fused phenanthrolinic moiety.

  13. Study on the biodegradation of perfluorooctanesulfonate (PFOS) and PFOS alternatives

    PubMed Central

    2016-01-01

    Objectives In this study, we investigated the biodegradation features of 4 perfluorooctanesulfonate (PFOS) alternatives developed at Changwon National University compared to those of PFOS. Methods Biodegradation testing was performed with microorganisms cultured in the good laboratory practice laboratory of the Korea Environment Corporation for 28 days following the Organization for Economic Cooperation and Development guidelines for the testing of chemicals (Test No. 301 C). Results While C8F17SO3Na, PFOS sodium salt was not degraded after 28 days, the 4 alternatives were biodegraded at the rates of 20.9% for C15F9H21S2O8Na2, 8.4% for C17F9H 25S2O8Na2, 22.6% for C23F18H28S2O8Na2, and 23.6% for C25F17H32O13S3Na3. Conclusions C25F17H32S3O13Na3, C23F18H28S2O8Na2, and C15F9H21S2O8Na2 were superior to PFOS in terms of biodegradation rates and surface tension, and thus they were considered highly applicable as PFOS alternatives. Environmental toxicity, human toxicity, and economic feasibility of these compounds should be investigated prior to their commercialization. PMID:26987483

  14. Comparison of eight different agars for the recovery of clinically relevant non-O157 Shiga toxin-producing Escherichia coli from baby spinach, cilantro, alfalfa sprouts and raw milk.

    PubMed

    Kase, Julie A; Maounounen-Laasri, Anna; Son, Insook; Lin, Andrew; Hammack, Thomas S

    2015-04-01

    The FDA Bacteriological Analytical Manual (BAM) Chapter 4a recommends several agars for isolating non-O157 Shiga toxin-producing Escherichia coli (STEC); not all have been thoroughly tested for recovering STECs from food. Using E. coli strains representing ten clinically relevant O serogroups (O26, O45, O91, O103, O104, O111, O113, O121, O128, O145) in artificially-contaminated fresh produce--bagged baby spinach, alfalfa sprouts, cilantro, and raw milk--we evaluated the performance of 8 different agars. Performance was highly dependent upon strain used and the presence of inhibitors, but not necessarily dependent on food matrix. Tellurite resistant-negative strains, O91:-, O103:H6, O104:H21, O113:H21, and O128, grew poorly on CHROMagar STEC, Rainbow agar O157, and a modified Rainbow O157 (mRB) agar. Although adding washed sheep's blood to CHROMagar STEC and mRB agars improved overall performance; however, this also reversed the inhibition of non-target bacteria provided by original formulations. Variable colony coloration made selecting colonies from Rainbow agar O157 and mRB agars difficult. Study results support a strategy using inclusive agars (e.g. L-EMB, SHIBAM) in combination with selective agars (R & F E. coli O157:H7, CHROMagar STEC) to allow for recovery of the most STECs while increasing the probability of recovering STEC in high bacterial count matrices. PMID:25475297

  15. Release of alkanes from sedimentary organic matter via sequential degradation involving catalytic hydropyrolysis

    SciTech Connect

    Love, G.D.; McAulay, A.; Snape, C.E.

    1996-12-31

    Fixed-bed pyrolysis of petroleum source rocks (type I and II kerogens) and high-volatile coals (type III ketogens) at high hydrogen pressures (> 10 MN, hydropyrolysis) in the presence of a dispersed sulphided molydenum catalyst gives rise to extremely high oil (dichloromethane-soluble) yields (>60%) with overall conversions of the organic matter being greater than 90%. The yields and conformations of the hopanes and steranes released from a selection of petroleum source rocks and coals by sequential dichloromethane and pyridine extraction, catalytic hydrogenation and hydropyrolysis will be presented, together with the influence of hydrogen pressure and heating rate on alkane yields and sterochemistry. The aim of the hydrogenation step (conducted at 300{degrees}C cf. 520{degrees}C for hydropyrolysis) in this sequential degradation scheme is to cleave only the weaker covalent bonds. The findings have demonstrated the unique ability of hydropyrolysis to mainline the yields of covalently-bound alkanes while maintaining the biologically-inherited 17{beta}(H), 21{beta}(H) stereochemistries of the hopanes, largely intact, even for coals. The total alkane yields from hydropyrolysis represented ca 30% w/w of the organic matter remaining in immature type I kerogens with yields of the C{sub 29}-C{sub 35} 17{beta}(H), 21{beta}(H) hopanes being much higher than from both normal pyrolysis and the hydrogenation step.

  16. Comparison of eight different agars for the recovery of clinically relevant non-O157 Shiga toxin-producing Escherichia coli from baby spinach, cilantro, alfalfa sprouts and raw milk.

    PubMed

    Kase, Julie A; Maounounen-Laasri, Anna; Son, Insook; Lin, Andrew; Hammack, Thomas S

    2015-04-01

    The FDA Bacteriological Analytical Manual (BAM) Chapter 4a recommends several agars for isolating non-O157 Shiga toxin-producing Escherichia coli (STEC); not all have been thoroughly tested for recovering STECs from food. Using E. coli strains representing ten clinically relevant O serogroups (O26, O45, O91, O103, O104, O111, O113, O121, O128, O145) in artificially-contaminated fresh produce--bagged baby spinach, alfalfa sprouts, cilantro, and raw milk--we evaluated the performance of 8 different agars. Performance was highly dependent upon strain used and the presence of inhibitors, but not necessarily dependent on food matrix. Tellurite resistant-negative strains, O91:-, O103:H6, O104:H21, O113:H21, and O128, grew poorly on CHROMagar STEC, Rainbow agar O157, and a modified Rainbow O157 (mRB) agar. Although adding washed sheep's blood to CHROMagar STEC and mRB agars improved overall performance; however, this also reversed the inhibition of non-target bacteria provided by original formulations. Variable colony coloration made selecting colonies from Rainbow agar O157 and mRB agars difficult. Study results support a strategy using inclusive agars (e.g. L-EMB, SHIBAM) in combination with selective agars (R & F E. coli O157:H7, CHROMagar STEC) to allow for recovery of the most STECs while increasing the probability of recovering STEC in high bacterial count matrices.

  17. An experimental study of the mechanism of the replacement of magnetite by pyrite up to 300 °C

    NASA Astrophysics Data System (ADS)

    Qian, Gujie; Brugger, Joël; Skinner, William M.; Chen, Guorong; Pring, Allan

    2010-10-01

    We present the results of an experimental study into the sulfidation of magnetite to form pyrite/marcasite under hydrothermal conditions (90-300 °C, vapor saturated pressures), a process associated with gold deposition in a number of ore deposits. The formation of pyrite/marcasite was studied as a function of reaction time, temperature, pH, sulfide concentration, solid-weight-to-fluid-volume ratio, and geometric surface area of magnetite in polytetrafluoroethylene-lined autoclaves (PTFE) and a titanium and stainless steel flow-through cell. Marcasite was formed only at pH 21°C <4 and was the dominant Fe disulfide at pH 21°C 1.11, while pyrite predominated at pH 21°C >2 and formed even under basic conditions (up to pH 21°C 12-13). Marcasite formation was favored at higher temperatures. Fine-grained pyrrhotite formed in the initial stage of the reaction together with pyrite in some experiments with large surface area of magnetite (grain size <125 μm). This pyrrhotite eventually gave way to pyrite. The transformation rate of magnetite to Fe disulfide increased with decreasing pH (at 120 °C; pH 120°C 0.96-4.42), and that rate of the transformation increased from 120 to 190 °C. Scanning electron microscope (SEM) imaging revealed that micro-pores (0.1-5 μm scale) existed at the reaction front between the parent magnetite and the product pyrite, and that the pyrite and/or marcasite were euhedral at pH 21°C <4 and anhedral at higher pH. The newly formed pyrite was micro-porous (0.1-5 μm); this micro-porosity facilitates fluid transport to the reaction interface between magnetite and pyrite, thus promoting the replacement reaction. The pyrite precipitated onto the parent magnetite was polycrystalline and did not preserve the crystallographic orientation of the magnetite. The pyrite precipitation was also observed on the PTFE liner, which is consistent with pyrite crystallizing from solution. The mechanism of the reaction is that of a dissolution

  18. Budgeting of major nutrients and the mitigation options for nutrient mining in semi-arid tropical agro-ecosystem of Tamil Nadu, India using NUTMON model.

    PubMed

    Surendran, U; Rama Subramoniam, S; Raja, P; Kumar, V; Murugappan, V

    2016-04-01

    Mining of nutrients from soil is a major problem in developing countries causing soil degradation and threaten long-term food production. The present study attempts to apply NUTrient MONitoring (NUTMON) model for carrying out nutrient budgeting to assess the stocks and flows of nitrogen (N), phosphorus (P), and potassium (K) in defined geographical unit based on the inputs, viz., mineral fertilizers, manures, atmospheric deposition, and sedimentation, and outputs, viz., harvested crop produces, residues, leaching, denitrification, and erosion losses. The study area covers Coimbatore and Erode Districts, which are potential agricultural areas in western agro-ecological zone of Tamil Nadu, India. The calculated nutrient balances for both the districts at district scale, using NUTMON methodology, were negative for nitrogen (N -3.3 and -10.1 kg ha(-1)) and potassium (K -58.6 and -9.8 kg ha(-1)) and positive for phosphorus (P +14.5 and 20.5 kg ha(-1)). Soil nutrient pool has to adjust the negative balance of N and K; there will be an expected mining of nutrient from the soil reserve. A strategy was attempted for deriving the fertilizer recommendation using Decision Support System for Integrated Fertilizer Recommendation (DSSIFER) to offset the mining in selected farms. The results showed that when DSSIFER recommended fertilizers are applied to crops, the nutrient balance was positive. NUTMON-Toolbox with DSSIFER would serve the purpose on enhancing soil fertility, productivity, and sustainability. The management options to mitigate nutrient mining with an integrated system approach are also discussed. PMID:27021693

  19. A Brownian Dynamics computational study of the interaction of spinach plastocyanin with turnip cytochrome f: the importance of plastocyanin conformational changes.

    PubMed

    Gross, Elizabeth L

    2007-01-01

    Brownian Dynamics (BD) computer simulations were used to study electrostatic interactions between turnip cytochrome f (cyt f) and spinach plastocyanin (PC). Three different spinach PC structures were studied: The X-ray crystal structure of Xue and coworkers [(1998) Protein Sci 7:2099-2105] and the NMR structure of Musiani et al. [(2005) J Biol Chem 280:18833-18841] and Ubbink and co-workers [(1998) Structure 6:323-335]. Significant differences exist in the backbone conformation between the PC taken from Ubbink and coworkers and the other two PC structures particularly the regions surrounding G10, E59-E60, and D51. Complexes formed in BD simulations using the PC of Ubbink and colleagues had a smaller Cu-Fe distance than the other two. These results suggest that different PC conformations may exist in solution with different capabilities of forming electron-transfer-active docks. All three types of complexes show electrostatic contacts between D42, E43, and D44 on PC and K187 on cyt f as well as between E59 on PC and K58 on cyt f. However, the PC of Ubbink and coworkers reveals additional contacts between D51 and cyt f as a result of the difference in backbone configuration. A second minor complex component was observed for the PC of Ubbink and co-workers and Xue and co-workers which had contacts between K187 on cyt f and E59 and E60 on PC rather than between K187 on cyt f and D42-D44 on PC as observed for the major components. This second type of complex may represent an earlier complex which rearranges to form a final complex capable of electron transfer.

  20. Interactions between CusF and CusB identified by NMR spectroscopy and chemical cross-linking coupled to mass spectrometry.

    PubMed

    Mealman, Tiffany D; Bagai, Ireena; Singh, Pragya; Goodlett, David R; Rensing, Christopher; Zhou, Hongjun; Wysocki, Vicki H; McEvoy, Megan M

    2011-04-01

    The Escherichia coli periplasmic proteins CusF and CusB, as part of the CusCFBA efflux system, aid in the resistance of elevated levels of copper and silver by direct metal transfer between the metallochaperone CusF and the membrane fusion protein CusB before metal extrusion from the periplasm to the extracellular space. Although previous in vitro experiments have demonstrated highly specific interactions between CusF and CusB that are crucial for metal transfer to occur, the structural details of the interaction have not been determined. Here, the interactions between CusF and CusB are mapped through nuclear magnetic resonance (NMR) spectroscopy and chemical cross-linking coupled with high-resolution mass spectrometry to better understand how recognition and metal transfer occur between these proteins. The NMR (1)H-(15)N correlation spectra reveal that CusB interacts with the metal-binding face of CusF. In vitro chemical cross-linking with a 7.7 Å homobifunctional amine-reactive cross-linker, BS(2)G, was used to capture the CusF/CusB interaction site, and mass spectral data acquired on an LTQ-Orbitrap confirm the following two cross-links: CusF K31 to CusB K29 and CusF K58 to CusB K32, thus revealing that the N-terminal region of CusB interacts with the metal-binding face of CusF. The proteins transiently interact in a metal-dependent fashion, and contacts between CusF and CusB are localized to regions near their respective metal-binding sites. PMID:21323389

  1. Molten salt CO2 capture and electro-transformation (MSCC-ET) into capacitive carbon at medium temperature: effect of the electrolyte composition.

    PubMed

    Deng, Bowen; Chen, Zhigang; Gao, Muxing; Song, Yuqiao; Zheng, Kaiyuan; Tang, Juanjuan; Xiao, Wei; Mao, Xuhui; Wang, Dihua

    2016-08-15

    Electrochemical transformation of CO2 into functional materials or fuels (i.e., carbon, CO) in high temperature molten salts has been demonstrated as a promising way of carbon capture, utilisation and storage (CCUS) in recent years. In a view of continuous operation, the electrolysis process should match very well with the CO2 absorption kinetics. At the same time, in consideration of the energy efficiency, a molten salt electrochemical cell running at lower temperature is more beneficial to a process powered by the fluctuating renewable electricity from solar/wind farms. Ternary carbonates (Li : Na : K = 43.5 : 31.5 : 25.0) and binary chlorides (Li : K = 58.5 : 41.5), two typical kinds of eutectic melt with low melting points and a wide electrochemical potential window, could be the ideal supporting electrolyte for the molten salt CO2 capture and electro-transformation (MSCC-ET) process. In this work, the CO2 absorption behaviour in Li2O/CaO containing carbonates and chlorides were investigated on a home-made gas absorption testing system. The electrode processes as well as the morphology and properties of carbon obtained in different salts are compared to each other. It was found that the composition of molten salts significantly affects the absorption of CO2, electrode processes and performance of the product. Furthermore, the relationship between the absorption and electro-transformation kinetics are discussed based on the findings. PMID:27193751

  2. Budgeting of major nutrients and the mitigation options for nutrient mining in semi-arid tropical agro-ecosystem of Tamil Nadu, India using NUTMON model.

    PubMed

    Surendran, U; Rama Subramoniam, S; Raja, P; Kumar, V; Murugappan, V

    2016-04-01

    Mining of nutrients from soil is a major problem in developing countries causing soil degradation and threaten long-term food production. The present study attempts to apply NUTrient MONitoring (NUTMON) model for carrying out nutrient budgeting to assess the stocks and flows of nitrogen (N), phosphorus (P), and potassium (K) in defined geographical unit based on the inputs, viz., mineral fertilizers, manures, atmospheric deposition, and sedimentation, and outputs, viz., harvested crop produces, residues, leaching, denitrification, and erosion losses. The study area covers Coimbatore and Erode Districts, which are potential agricultural areas in western agro-ecological zone of Tamil Nadu, India. The calculated nutrient balances for both the districts at district scale, using NUTMON methodology, were negative for nitrogen (N -3.3 and -10.1 kg ha(-1)) and potassium (K -58.6 and -9.8 kg ha(-1)) and positive for phosphorus (P +14.5 and 20.5 kg ha(-1)). Soil nutrient pool has to adjust the negative balance of N and K; there will be an expected mining of nutrient from the soil reserve. A strategy was attempted for deriving the fertilizer recommendation using Decision Support System for Integrated Fertilizer Recommendation (DSSIFER) to offset the mining in selected farms. The results showed that when DSSIFER recommended fertilizers are applied to crops, the nutrient balance was positive. NUTMON-Toolbox with DSSIFER would serve the purpose on enhancing soil fertility, productivity, and sustainability. The management options to mitigate nutrient mining with an integrated system approach are also discussed.

  3. Position for site-specific attachment of a DOTA chelator to synthetic affibody molecules has a different influence on the targeting properties of 68Ga- compared to 111in-labeled conjugates.

    PubMed

    Honarvar, Hadis; Strand, Joanna; Perols, Anna; Orlova, Anna; Selvaraju, Ram Kumar; Eriksson Karlström, Amelie; Tolmachev, Vladimir

    2014-01-01

    Affibody molecules, small (7 kDa) scaffold proteins, are a promising class of probes for radionuclide molecular imaging. Radiolabeling of Affibody molecules with the positron-emitting nuclide 68Ga would permit the use of positron emission tomography (PET), providing better resolution, sensitivity, and quantification accuracy than single-photon emission computed tomography (SPECT). The synthetic anti-HER2 ZHER2:S1 Affibody molecule was conjugated with DOTA at the N-terminus, in the middle of helix 3, or at the C-terminus. The biodistribution of 68Ga- and 111In-labeled Affibody molecules was directly compared in NMRI nu/nu mice bearing SKOV3 xenografts. The position of the chelator strongly influenced the biodistribution of the tracers, and the influence was more pronounced for 68Ga-labeled Affibody molecules than for the 111In-labeled counterparts. The best 68Ga-labeled variant was 68Ga-[DOTA-A1]-ZHER2:S1, which provided a tumor uptake of 13 ± 1 %ID/g and a tumor to blood ratio of 39 ± 12 at 2 hours after injection. 111In-[DOTA-A1]-ZHER2:S1 and 111In-[DOTA-K58]-ZHER2:S1 were equally good at this time point, providing a tumor uptake of 15 to 16 %ID/g and a tumor to blood ratio in the range of 60 to 80. In conclusion, the selection of the best position for a chelator in Affibody molecules can be used for optimization of their imaging properties. This may be important for the development of Affibody-based and other protein-based imaging probes. PMID:25249017

  4. Molten salt CO2 capture and electro-transformation (MSCC-ET) into capacitive carbon at medium temperature: effect of the electrolyte composition.

    PubMed

    Deng, Bowen; Chen, Zhigang; Gao, Muxing; Song, Yuqiao; Zheng, Kaiyuan; Tang, Juanjuan; Xiao, Wei; Mao, Xuhui; Wang, Dihua

    2016-08-15

    Electrochemical transformation of CO2 into functional materials or fuels (i.e., carbon, CO) in high temperature molten salts has been demonstrated as a promising way of carbon capture, utilisation and storage (CCUS) in recent years. In a view of continuous operation, the electrolysis process should match very well with the CO2 absorption kinetics. At the same time, in consideration of the energy efficiency, a molten salt electrochemical cell running at lower temperature is more beneficial to a process powered by the fluctuating renewable electricity from solar/wind farms. Ternary carbonates (Li : Na : K = 43.5 : 31.5 : 25.0) and binary chlorides (Li : K = 58.5 : 41.5), two typical kinds of eutectic melt with low melting points and a wide electrochemical potential window, could be the ideal supporting electrolyte for the molten salt CO2 capture and electro-transformation (MSCC-ET) process. In this work, the CO2 absorption behaviour in Li2O/CaO containing carbonates and chlorides were investigated on a home-made gas absorption testing system. The electrode processes as well as the morphology and properties of carbon obtained in different salts are compared to each other. It was found that the composition of molten salts significantly affects the absorption of CO2, electrode processes and performance of the product. Furthermore, the relationship between the absorption and electro-transformation kinetics are discussed based on the findings.

  5. Molecular and Genetic Characterization of HIV-1 Tat Exon-1 Gene from Cameroon Shows Conserved Tat HLA-Binding Epitopes: Functional Implications

    PubMed Central

    Teto, Georges; Fonsah, Julius Y.; Tagny, Claude T.; Mbanya, Dora; Nchindap, Emilienne; Kenmogne, Leopoldine; Fokam, Joseph; Njamnshi, Dora M.; Kouanfack, Charles; Njamnshi, Alfred K.; Kanmogne, Georgette D.

    2016-01-01

    HIV-1 Tat plays a critical role in viral transactivation. Subtype-B Tat has potential use as a therapeutic vaccine. However, viral genetic diversity and population genetics would significantly impact the efficacy of such a vaccine. Over 70% of the 37-million HIV-infected individuals are in sub-Saharan Africa (SSA) and harbor non-subtype-B HIV-1. Using specimens from 100 HIV-infected Cameroonians, we analyzed the sequences of HIV-1 Tat exon-1, its functional domains, post-translational modifications (PTMs), and human leukocyte antigens (HLA)-binding epitopes. Molecular phylogeny revealed a high genetic diversity with nine subtypes, CRF22_01A1/CRF01_AE, and negative selection in all subtypes. Amino acid mutations in Tat functional domains included N24K (44%), N29K (58%), and N40K (30%) in CRF02_AG, and N24K in all G subtypes. Motifs and phosphorylation analyses showed conserved amidation, N-myristoylation, casein kinase-2 (CK2), serine and threonine phosphorylation sites. Analysis of HLA allelic frequencies showed that epitopes for HLAs A*0205, B*5301, Cw*0401, Cw*0602, and Cw*0702 were conserved in 58%–100% of samples, with B*5301 epitopes having binding affinity scores > 100 in all subtypes. This is the first report of N-myristoylation, amidation, and CK2 sites in Tat; these PTMs and mutations could affect Tat function. HLA epitopes identified could be useful for designing Tat-based vaccines for highly diverse HIV-1 populations, as in SSA. PMID:27438849

  6. First Palaeogene sedimentary rock palaeomagnetic pole from stable western Eurasia and tectonic implications

    NASA Astrophysics Data System (ADS)

    Ali, Jason R.; Ward, David J.; King, Chris; Abrajevitch, Alexandra

    2003-08-01

    A palaeomagnetic investigation of lower Eocene (ca. 52 Ma) London Clay Formation cemented mudstones from Sheppey (SE England) has yielded a mean direction of Dec. = 1.1°, Inc. = 43.2°, where N= 9, α95 = 6.8° and K= 58.5. This apparently high-quality direction (Q-factor = 5) has an associated palaeopole of 178.6°E, 63.7°N, where A95= 6.8°. The data represent the first pole from post Jurassic stable Eurasia rocks outside of the European North Atlantic Igneous Province (NAIP), of which most results have been obtained from NW Britain and the Faroe Islands. The data can in part be used to constrain the position of Palaeogene Eurasia, in particular the zero-offset declination implying negligible rotation of western Eurasia since the early Cenozoic. This is in contrast with data derived from the European NAIP, which imply small to moderate clockwise rotations for this part of the plate. The inclination angle may provide less useful information as it appears to be anomalously shallow when compared with that associated with the NAIP derived poles. In an attempt to understand the shallowing, we re-examined data from Palaeocene-Eocene sediments recovered in several boreholes (bathyal sediments in DSDP Hole 550, four cores through fluvio-delatic to middle shelf sequences in the London area, and one borehole sequence from East Anglia). In all cases, the sediments show systematic inclination shallowing similar in magnitude to that reported from Sheppey. Tectonic and geomagnetic explanations can be discounted; sediment compaction appears to be the likely cause. In light of the current controversy surrounding the `stable Asia shallow inclination problem', the result reinforces the suggestion that tectonic modelling needs to be done carefully when the supporting data are based exclusively on palaeomagnetic studies of sedimentary rocks.

  7. In situ-ATR-FTIR analysis on the uptake and release of streptomycin from polyelectrolyte complex layers

    NASA Astrophysics Data System (ADS)

    Torger, B.; Müller, M.

    2013-03-01

    In-situ ATR-FTIR spectroscopy and line shape analysis of the diagnostic spectral region was used to quantify the bound amount and release of the antibiotic streptomycin (STRP) at polyelectrolyte (PEL) multilayers (PEM) of poly(ethyleneimine) (PEI) and poly(acrylic acid) (PAA) or PEI and sodium alginate (ALG). Unlike common concepts based on the drug enrichment of the release medium, this analytical concept allowed to measure quantitatively the drug depletion in the delivery matrix. The measured kinetic in situ ATR-FTIR data were analysed by a modified Korsmeyer-Peppas equation based on two characteristic release parameters k and n. As main experimental parameters the number of PEL layers (adsorption steps) z and the STRP/PEL ratio were varied. For z = 8 the STRP/PEL ratio showed the most significant influence on release kinetics, whereby for STRP/PEL = 1:25 slowest (n = 0.77) and lowest (k = 21.4%) and for STRP/PEL = 1:5 most rapid (n = 0.30) and highest (k = 58.6%) drug releases were found. PEM-PEI/ALG-8 (STRP/PEL = 1:5) revealed slower release rates (n = 0.58) and lower released STRP amounts (k = 17.1%) compared to PEI/PAA. UV-VIS data on time dependent STRP enrichment of the release medium showed a similar trend compared to respective ATR-FTIR data on STRP depletion in PEM. Released amounts of around 1-2 mg from the herein introduced PEM films could be determined. The introduced analytical concept will be used as screening tool for other drugs, drug eluting films and bone substituting materials.

  8. Interactions between CusF and CusB identified by NMR spectroscopy and chemical cross-linking coupled to mass spectrometry

    PubMed Central

    Mealman, Tiffany D.; Bagai, Ireena; Singh, Pragya; Goodlett, David R.; Rensing, Christopher; Zhou, Hongjun; Wysocki, Vicki H.; McEvoy, Megan M.

    2011-01-01

    The E. coli periplasmic proteins CusF and CusB, as part of the CusCFBA efflux system, aid in the resistance of elevated levels of copper and silver by direct metal transfer between the metallochaperone CusF and the membrane fusion protein CusB, before metal extrusion from the periplasm to the extracellular space. Although previous in vitro experiments have demonstrated highly specific interactions between CusF and CusB that are crucial for metal transfer to occur, the structural details of the interaction have not been determined. Here, the interactions between CusF and CusB are mapped through nuclear magnetic resonance (NMR) spectroscopy and chemical cross-linking coupled with high-resolution mass spectrometry to better understand how recognition and metal transfer occur between these proteins. The NMR 1H-15N correlation spectra reveal that CusB interacts with the metal-binding face of CusF. In vitro chemical cross-linking with a 7.7 Å homobifunctional amine-reactive cross-linker, BS2G, was used to capture the CusF/CusB interaction site and mass spectral data acquired on an LTQ-Orbitrap confirm the following two cross-links: CusF K31 to CusB K29 and CusF K58 to CusB K32; thus, revealing that the N-terminal region of CusB interacts with the metal-binding face of CusF. The proteins transiently interact in a metal-dependent fashion and contacts between CusF and CusB are localized to regions near their respective metal binding sites. PMID:21323389

  9. One severe acute respiratory syndrome coronavirus protein complex integrates processive RNA polymerase and exonuclease activities.

    PubMed

    Subissi, Lorenzo; Posthuma, Clara C; Collet, Axelle; Zevenhoven-Dobbe, Jessika C; Gorbalenya, Alexander E; Decroly, Etienne; Snijder, Eric J; Canard, Bruno; Imbert, Isabelle

    2014-09-16

    In addition to members causing milder human infections, the Coronaviridae family includes potentially lethal zoonotic agents causing severe acute respiratory syndrome (SARS) and the recently emerged Middle East respiratory syndrome. The ∼30-kb positive-stranded RNA genome of coronaviruses encodes a replication/transcription machinery that is unusually complex and composed of 16 nonstructural proteins (nsps). SARS-CoV nsp12, the canonical RNA-dependent RNA polymerase (RdRp), exhibits poorly processive RNA synthesis in vitro, at odds with the efficient replication of a very large RNA genome in vivo. Here, we report that SARS-CoV nsp7 and nsp8 activate and confer processivity to the RNA-synthesizing activity of nsp12. Using biochemical assays and reverse genetics, the importance of conserved nsp7 and nsp8 residues was probed. Whereas several nsp7 mutations affected virus replication to a limited extent, the replacement of two nsp8 residues (P183 and R190) essential for interaction with nsp12 and a third (K58) critical for the interaction of the polymerase complex with RNA were all lethal to the virus. Without a loss of processivity, the nsp7/nsp8/nsp12 complex can associate with nsp14, a bifunctional enzyme bearing 3'-5' exoribonuclease and RNA cap N7-guanine methyltransferase activities involved in replication fidelity and 5'-RNA capping, respectively. The identification of this tripartite polymerase complex that in turn associates with the nsp14 proofreading enzyme sheds light on how coronaviruses assemble an RNA-synthesizing machinery to replicate the largest known RNA genomes. This protein complex is a fascinating example of the functional integration of RNA polymerase, capping, and proofreading activities. PMID:25197083

  10. One severe acute respiratory syndrome coronavirus protein complex integrates processive RNA polymerase and exonuclease activities

    PubMed Central

    Subissi, Lorenzo; Posthuma, Clara C.; Collet, Axelle; Zevenhoven-Dobbe, Jessika C.; Gorbalenya, Alexander E.; Decroly, Etienne; Snijder, Eric J.; Canard, Bruno; Imbert, Isabelle

    2014-01-01

    In addition to members causing milder human infections, the Coronaviridae family includes potentially lethal zoonotic agents causing severe acute respiratory syndrome (SARS) and the recently emerged Middle East respiratory syndrome. The ∼30-kb positive-stranded RNA genome of coronaviruses encodes a replication/transcription machinery that is unusually complex and composed of 16 nonstructural proteins (nsps). SARS-CoV nsp12, the canonical RNA-dependent RNA polymerase (RdRp), exhibits poorly processive RNA synthesis in vitro, at odds with the efficient replication of a very large RNA genome in vivo. Here, we report that SARS-CoV nsp7 and nsp8 activate and confer processivity to the RNA-synthesizing activity of nsp12. Using biochemical assays and reverse genetics, the importance of conserved nsp7 and nsp8 residues was probed. Whereas several nsp7 mutations affected virus replication to a limited extent, the replacement of two nsp8 residues (P183 and R190) essential for interaction with nsp12 and a third (K58) critical for the interaction of the polymerase complex with RNA were all lethal to the virus. Without a loss of processivity, the nsp7/nsp8/nsp12 complex can associate with nsp14, a bifunctional enzyme bearing 3′-5′ exoribonuclease and RNA cap N7-guanine methyltransferase activities involved in replication fidelity and 5′-RNA capping, respectively. The identification of this tripartite polymerase complex that in turn associates with the nsp14 proofreading enzyme sheds light on how coronaviruses assemble an RNA-synthesizing machinery to replicate the largest known RNA genomes. This protein complex is a fascinating example of the functional integration of RNA polymerase, capping, and proofreading activities. PMID:25197083

  11. Synthesis, spectroscopic, structural and theoretical characterization of hydrogensquarate and mononuclear Au(III)-complex of dipeptide phenylalanyltyrosine

    NASA Astrophysics Data System (ADS)

    Koleva, Bojidarka B.; Kolev, Tsonko; Zareva, Sonya Y.; Spiteller, Michael

    2008-08-01

    The mononuclear Au(III)-complex ([Au(C 18H 18N 2O 4)Cl]) and hydrogensquarate ([C 22H 21N 2O 8]) of dipeptide phenylalanyltyrosine ( H-Phe-Tyr-OH) have been synthezised, characterized spectroscopically and structurally by means of solid-state linear-polarized IR-spectroscopy, 1H- and 13C-NMR, ESI-MS, HPLC-MS-MS, FAB-MS, TGS and DSC methods. The structure of the Au(III)-complex has been predicted theoretically by DFT calculations. The dipeptide coordinated in a tridentate manner via -NH 2, -COO - and N --groups. One Cl - ion is attached to the metal centre as a terminal ligand, yielding a planar AuN 2OCl chromophor. The hydrogensquarate consists in positive charged dipeptide moiety and negative one hydrogensquarate (HSq -) anion stabilizing by strong intermolecular hydrogen bonds.

  12. Crystal structure of dimethyl 3,3′-[(3-nitro­phen­yl)methyl­ene]bis­(1H-indole-2-carboxyl­ate) ethanol monosolvate

    PubMed Central

    Sun, Hong-Shun; Li, Yu-Long; Jiang, Hong; Xu, Ning; Xu, Hong

    2014-01-01

    In the title compound, C27H21N3O6·C2H5OH, the indole ring systems are approximately perpendicular to each other, with a dihedral angle of 89.3 (5)°; the plane of the benzene ring is oriented with respect to the indole ring systems at 49.9 (5) and 73.4 (3)°. In the crystal, mol­ecules are linked by N—H⋯O and O—H⋯O hydrogen bonds and weak C—H⋯π inter­actions into a three-dimensional supra­molecular architecture. A void of 33.0 (7) Å3 is observed in the crystal structure. The solvent ethanol molecule acts as a donor, forming an O—H⋯O hydrogen bond, reinforcing the framework structure. PMID:25484748

  13. Crystal structure of dimethyl 3,3′-[(4-fluoro­phen­yl)methyl­ene]bis­(1H-indole-2-carboxyl­ate)

    PubMed Central

    Sun, Hong-Shun; Li, Yu-long; Jiang, Hong; Xu, Ning; Xu, Hong

    2015-01-01

    In the title compound, C27H21FN2O4, the mean planes of the indole ring systems (r.m.s. deviations = 0.0263 and 0.0160 Å) are approximately perpendic­ular to one another, making a dihedral angle of 84.0 (5)°; the fluoro­benzene ring is twisted with respect to the mean planes of the two indole ring systems at 89.5 (5) and 84.6 (3)°. In the crystal, pairs of N—H⋯O hydrogen bonds link the mol­ecules into inversion dimers, which are further linked by N—H⋯O hydrogen bonds into supra­molecular chains propagated along the b-axis direction. Weak C—H⋯π inter­actions are observed between neighbouring chains. PMID:26594391

  14. Crystal structure of (1,3-di-tert-butyl-η(5)-cyclo-penta-dien-yl)tri-methyl-hafnium(IV).

    PubMed

    Pérez-Redondo, Adrián; Varela-Izquierdo, Víctor; Yélamos, Carlos

    2015-05-01

    The mol-ecule of the title organometallic hafnium(IV) com-pound, [Hf(CH3)3(C13H21)] or [HfMe3(η(5)-C5H3-1,3- (t) Bu2)], adopts the classical three-legged piano-stool geometry for mono-cyclo-penta-dienylhafnium(IV) derivatives with the three methyl groups bonded to the Hf(IV) atom at the legs. The C atoms of the two tert-butyl group bonded to the cyclo-penta-dienyl (Cp) ring are 0.132 (5) and 0.154 (6) Å above the Cp least-squares plane. There are no significant inter-molecular inter-actions present between the mol-ecules in the crystal structure.

  15. Crystal structure of (1,3-di-tert-butyl-η5-cyclo­penta­dien­yl)tri­methyl­hafnium(IV)

    PubMed Central

    Pérez-Redondo, Adrián; Varela-Izquierdo, Víctor; Yélamos, Carlos

    2015-01-01

    The mol­ecule of the title organometallic hafnium(IV) com­pound, [Hf(CH3)3(C13H21)] or [HfMe3(η5-C5H3-1,3-tBu2)], adopts the classical three-legged piano-stool geometry for mono­cyclo­penta­dienylhafnium(IV) derivatives with the three methyl groups bonded to the Hf(IV) atom at the legs. The C atoms of the two tert-butyl group bonded to the cyclo­penta­dienyl (Cp) ring are 0.132 (5) and 0.154 (6) Å above the Cp least-squares plane. There are no significant inter­molecular inter­actions present between the mol­ecules in the crystal structure. PMID:25995884

  16. Crystal structure of 5-[4-(di­ethyl­amino)­benzyl­idene]-2,2-dimethyl-1,3-dioxane-4,6-dione

    PubMed Central

    Stepina, Egija; Stepanovs, Dmitrijs; Mierina, Inese; Jure, Mara

    2015-01-01

    The title compound, C17H21NO4, consists of substituted Meldrum’s acid with a [4-(di­ethyl­amino)­phen­yl]methyl­idene fragment attached to the fifth position. The heterocycle assumes a distorted boat conformation. The planar part of heterocycle is almost coplanar with the benzene ring due to the presence of a long conjugated system in the mol­ecule. This leads to the formation of C—H⋯O-type intra­molecular contacts. As a result of the absence of hydrogen-bond donors in the structure, the crystal packing is controlled by van der Waals forces and weak C—H⋯O inter­actions, which associate the mol­ecules into inversion dimers. PMID:26594416

  17. Crystal structure of 5-[4-(di-ethyl-amino)-benzyl-idene]-2,2-dimethyl-1,3-dioxane-4,6-dione.

    PubMed

    Stepina, Egija; Stepanovs, Dmitrijs; Mierina, Inese; Jure, Mara

    2015-10-01

    The title compound, C17H21NO4, consists of substituted Meldrum's acid with a [4-(di-ethyl-amino)-phen-yl]methyl-idene fragment attached to the fifth position. The heterocycle assumes a distorted boat conformation. The planar part of heterocycle is almost coplanar with the benzene ring due to the presence of a long conjugated system in the mol-ecule. This leads to the formation of C-H⋯O-type intra-molecular contacts. As a result of the absence of hydrogen-bond donors in the structure, the crystal packing is controlled by van der Waals forces and weak C-H⋯O inter-actions, which associate the mol-ecules into inversion dimers. PMID:26594416

  18. Crystal growth and characterization studies of novel luminescent 2D coordination polymer of lead-benzilate possessing edge sharing PbO6 polyhedra

    NASA Astrophysics Data System (ADS)

    Soumya Mol, U. S.; Drisya, R.; Satheesh Chandran, P. R.; Sudarsanakumar, M. R.; Suma, S.; Sudhadevi Antharjanam, P. K.

    2016-12-01

    Single crystals of a new coordination polymer of lead-benzilate, C28H21O6Pb·C2H5OH have been successfully grown by gel diffusion technique at room temperature. The colourless single crystals were obtained within a week. The crystal structure was elucidated using single crystal X-ray diffraction studies. The compound possesses a polymeric structure constructed from edge sharing PbO6 polyhedra. Single crystal X-ray diffraction analysis showed that the compound crystallizes in triclinic space group P-1. The grown crystals were further characterized by elemental analysis, FT-IR, UV-Visible and thermogravimetric analysis. The photoluminescent properties of the complex and the ligand were also investigated.

  19. Crystal structure of dimethyl 3,3′-[(3-fluoro­phenyl)methyl­ene]bis­(1H-indole-2-carboxyl­ate)

    PubMed Central

    Lu, Xin-Hua; Sun, Hong-Shun; Hu, Jin

    2014-01-01

    In the title compound, C27H21FN2O4, the mean planes of the two indole ring systems (r.m.s. deviations = 0.0166 and 0.0086 Å) are approximately perpendic­ular to one another, making a dihedral angle of 87.8 (5)°; the fluorobenzene ring is twisted with respect to the mean planes of the two indole ring systems at 82.7 (5) and 85.5 (3)°. In the crystal, pairs of N—H⋯O hydrogen bonds link the mol­ecules into the inversion dimers, which are further linked by N—H⋯O hydrogen bonds into supra­molecular chains propagating along the b-axis direction. Weak C—H⋯π inter­actions are observed between neighbouring chains. PMID:25553001

  20. Crystal structure of Brinzolamide: a carbonic anhydrase inhibitor.

    PubMed

    Zheng, Huirong; Lou, Benyong

    2016-05-01

    In crystal structure of the title compound, C12H21N3O5S3 [systematic name: (R)-4-ethyl-amino-2-(3-meth-oxy-prop-yl)-3,4-di-hydro-2H-thieno[3,2-e][1,2]thia-zine-6-sulfonamide 1,1-dioxide], there exist three kinds of hydrogen-bonding inter-actions. The sulfonamide group is involved in hydrogen bonding with the secondary amine and the meth-oxy O atom, resulting in the formation of layers parallel to the bc plane. The layers are linked by an N-H⋯O hydrogen bond involving a sulfonamide O atom as acceptor and the secondary amine H atom as donor, which gives rise to the formation of a unique bilayer structure. The absolute structure of the mol-ecule in the crystal was determined by resonant scattering [Flack parameter = 0.01 (4)]. PMID:27308020

  1. Crystal structure of zwitterionic 2-[bis-(2-meth-oxy-phen-yl)phosphanium-yl]-4-methyl-benzene-sulfonate monohydrate di-chloro-methane monosolvate.

    PubMed

    Zhang, Hongyang; Feng, Ge; Filatov, Alexander S; Jordan, Richard F

    2016-02-01

    In the title compound, C21H21O5PS·H2O·CH2Cl2, the phospho-nium-sulfonate zwitterion has the acidic H atom located on the P atom rather than the sulfonate group. The S-O bond lengths [1.4453 (15)-1.4521 (14) Å] are essentially equal. In the crystal, the water mol-ecules bridge two zwitterions via Owater-H⋯Osulfonate hydrogen bonds into a centrosymmetric dimer. The dimers are further linked by weak CAr-yl-H⋯Osulfonate hydrogen bonds into chains extending along [100]. The PH(+) group is not involved in inter-molecular inter-actions. PMID:26958395

  2. Crystal structure of (2Z,5Z)-3-(4-meth-oxy-phen-yl)-2-[(4-meth-oxy-phenyl)-imino]-5-[(E)-3-(2-nitro-phen-yl)allyl-idene]-1,3-thia-zolidin-4-one.

    PubMed

    Rahmani, Rachida; Djafri, Ahmed; Daran, Jean-Claude; Djafri, Ayada; Chouaih, Abdelkader; Hamzaoui, Fodil

    2016-02-01

    In the title compound, C26H21N3O5S, the thia-zole ring is nearly planar with a maximum deviation of 0.017 (2) Å, and is twisted with respect to the three benzene rings, making dihedral angles of 25.52 (12), 85.77 (12) and 81.85 (13)°. In the crystal, weak C-H⋯O hydrogen bonds and C-H⋯π inter-actions link the mol-ecules into a three-dimensional supra-molecular architecture. Aromatic π-π stacking is also observed between the parallel nitro-benzene rings of neighbouring mol-ecules, the centroid-to-centroid distance being 3.5872 (15) Å. PMID:26958377

  3. Crystal structure of 3-de-oxy-3-nitro-methyl-1,2;5,6-di-O-iso-propyl-idene-α-d-allo-furan-ose.

    PubMed

    Lugiņina, Jevgeņija; Rjabovs, Vitālijs; Stepanovs, Dmitrijs

    2016-03-01

    The title compound, C13H21NO7 {systematic name: (3aR,5S,6R,6aR)-5-[(R)-2,2-dimethyl-1,3-dioxolan-4-yl]-2,2-dimethyl-6-(nitro-meth-yl)tetra-hydro-furo[2,3-d][1,3]dioxole}, consists of a substituted 2,2-di-methyl-tetra-hydro-furo[2,3-d][1,3]dioxolane skeleton. The furan-ose ring A adopts a (o)T 4 conformation. The fused dioxolane ring B and the substituent dioxolane ring C also have twisted conformations. There are no strong hydrogen bonds in the crystal structure: only weak C-H⋯O contacts are present, which link the mol-ecules to form a three-dimensional structure. PMID:27006795

  4. Crystal structures of 1-(4-chloro­phen­yl)-2-(di­phenyl­phosphor­yl)ethan-1-one and 1-(di­phenyl­phosphor­yl)-3,3-di­methyl­butan-2-one

    PubMed Central

    Leach, Erin G.; Kulesza, Alyssa A.; Staples, Richard J.; Biros, Shannon M.

    2015-01-01

    The title compounds, C20H16ClO2P, (I), and C18H21O2P, (II), were synthesized via an Arbuzov reaction between an α-bromo­ketone and isopropoxydi­phenyl­phosphane. In the crystals of both compounds, mol­ecules are linked via bifurcated C—H⋯(O,O) hydrogen bonds, forming chains propagating along [100] for (I) and along [010] for (II). The chains are linked via C—H⋯π inter­actions, leading to the formation of sheets lying parallel to (010) for (I) and (001) for (II). The absolute structure of compound (II) was determined by resonant scattering [Flack parameter = 0.088 (14)]. PMID:25995871

  5. Hydrogen-bonded and π-interaction assembly in two 8-alkoxycarbonyl-1,8-diazabicyclo[5.4.0]undec-7-enium chloride salts.

    PubMed

    Mesto, E; Quaranta, E

    2013-04-01

    The crystal structures of 8-phenoxycarbonyl-1,8-diazabicyclo[5.4.0]undec-7-enium chloride, C16H21N2O2(+)·Cl(-), (I), and 8-methoxycarbonyl-1,8-diazabicyclo[5.4.0]undec-7-enium chloride monohydrate, C11H19N2O2(+)·Cl(-)·H2O, (II), recently reported by Carafa, Mesto & Quaranta [Eur. J. Org. Chem. (2011), pp. 2458-2465], are analysed and discussed with a focus on crystal interaction assembly. Both compounds crystallize in the space group P2(1)/c. The crystal packings are characterized by dimers linked through π-π stacking interactions and intermolecular nonclassical hydrogen bonds, respectively. Additional intermolecular C-H···Cl interactions [in (I) and (II)] and classical O-H···Cl hydrogen bonds [in (II)] are also evident and contribute to generating three-dimensional hydrogen-bonded networks.

  6. Crystal structure of 3-de­oxy-3-nitro­methyl-1,2;5,6-di-O-iso­propyl­idene-α-d-allo­furan­ose

    PubMed Central

    Lugiņina, Jevgeņija; Rjabovs, Vitālijs; Stepanovs, Dmitrijs

    2016-01-01

    The title compound, C13H21NO7 {systematic name: (3aR,5S,6R,6aR)-5-[(R)-2,2-dimethyl-1,3-dioxolan-4-yl]-2,2-dimethyl-6-(nitro­meth­yl)tetra­hydro­furo[2,3-d][1,3]dioxole}, consists of a substituted 2,2-di­methyl­tetra­hydro­furo[2,3-d][1,3]dioxolane skeleton. The furan­ose ring A adopts a oT 4 conformation. The fused dioxolane ring B and the substituent dioxolane ring C also have twisted conformations. There are no strong hydrogen bonds in the crystal structure: only weak C—H⋯O contacts are present, which link the mol­ecules to form a three-dimensional structure. PMID:27006795

  7. Studies on flower initiation of Super-Dwarf wheat under stress conditions simulating those on the Space Station, Mir

    NASA Technical Reports Server (NTRS)

    Jiang, L.; Salisbury, F. B.; Campbell, W. F.; Carman, J. G.; Nan, R.

    1998-01-01

    Super-Dwarf wheat plants were grown in growth chambers under 12 treatments with three photoperiods (18 h, 21 h, 24 h) and four carbon dioxide (CO2) levels (360, 1,200, 3,000 and 7,000 micromoles mol-1). Carbon dioxide concentrations affected flower initiation rates of Super-Dwarf wheat. The optimum CO2 level for flower initiation and development was 1,200 micromoles mol-1. Super-optimum CO2 levels delayed flower initiation, but did not decrease final flower bud number per head. Longer photoperiods not only accelerated flower initiation rates, but also decreased deleterious effects of super-optimum CO2. Flower bud size and head length at the same developmental stage were larger under longer photoperiods, but final flower bud number was not affected by photoperiod.

  8. High-resolution mapping of D16led-1, Gart, Gas-4, Cbr, Pcp-4, and Erg on distal mouse chromosome 16.

    PubMed

    Mjaatvedt, A E; Citron, M P; Reeves, R H

    1993-08-01

    More than 500 backcross progeny from four intersubspecific backcrosses were typed for six markers on distal mouse chromosome 16. Five of these represented genes that mapped within the Sod-1 to Ets-2 interval, which was shown previously to contain the weaver (wv) gene. The map order, including previously mapped reference markers, is (cen)-D16H21S16-D16Led-1-App-Sod-1-Gart-Gas-4-Cbr++ +-wv-Pcp-4-Erg-Ets-2. This gene order recapitulates the order of the genes on human chromosome 21 where known. Two of these markers further define the region containing the weaver gene to a 3.9-cM segment between Cbr and Pcp-4. In addition, Pcp-4 was localized to human chromosome 21 by the presence of a human-specific restriction fragment in WAV-17, a mouse-human somatic cell hybrid with human chromosome 21 as the only human contribution.

  9. [Occurrence of Salmonella spp. and shigatoxin-producing escherichia coli (STEC) in horse faeces and horse meat products].

    PubMed

    Pichner, Rohtraud; Sander, Andrea; Steinrück, Hartmut; Gareis, Manfred

    2005-01-01

    In order to assess the relevance of horses as a possible reservoir of Salmonella and Shigatoxin-producing Escherichia coli (STEC), 400 samples of horse faeces and 100 samples of horse meat products were examined by PCR-screening methods. Salmonella enterica was not found in any of the samples. One faeces-sample and one horse meat product were proved to be STEC positive. The STEC-strain from faecal origin belonged to the serotype 0113:H21 and had the stx 2c gene and the enterohemolysin gene. The STEC-strain isolated from a horse meat product had the serotype O87:H16 and the stx 2d gene. The results indicate a very low risk for human to get a Salmonella- or EHEC- infection from horses in Germany.

  10. Crystal structure of bis-{N-[(di-ethyl-amino)-dimethyl-sil-yl]anilido-κ(2) N,N'}zinc.

    PubMed

    Chen, Juan

    2015-12-01

    The title zinc amide, [Zn(C12H21N2Si)2], was prepared by the metathetical reaction of [LiN(SiMe2NEt2)(C6H5)]2 with zinc dichloride. It is mononuclear and the mol-ecule is generated by twofold rotation symmetry. The central Zn(II) atom is N,N'-chelated by each of the two N-silylated anilide ligands in a highly distorted tetra-hedral environment. Two N-Si-N ligands are arranged in a cis fashion around the Zn(II) atom. The Zn-Namine bonds [2.2315 (12) Å] are much longer than the Zn-Nanilide bonds [1.9367 (11) Å]. PMID:26870447

  11. Crystal structure of bis­{N-[(di­ethyl­amino)­dimethyl­sil­yl]anilido-κ2 N,N′}zinc

    PubMed Central

    Chen, Juan

    2015-01-01

    The title zinc amide, [Zn(C12H21N2Si)2], was prepared by the metathetical reaction of [LiN(SiMe2NEt2)(C6H5)]2 with zinc dichloride. It is mononuclear and the mol­ecule is generated by twofold rotation symmetry. The central ZnII atom is N,N′-chelated by each of the two N-silylated anilide ligands in a highly distorted tetra­hedral environment. Two N—Si—N ligands are arranged in a cis fashion around the ZnII atom. The Zn—Namine bonds [2.2315 (12) Å] are much longer than the Zn—Nanilide bonds [1.9367 (11) Å]. PMID:26870447

  12. 3-[2-(Triphenyl­phosphanyl­idene)acet­yl]-2H-chromen-2-one

    PubMed Central

    Taha, Muhammad; Ismail, Nor Hadiani; Aziza, Ahmad Nazif; Shah, Syed Adnan Ali; Yousuf, Sammer

    2013-01-01

    In the title compound, C29H21O3P, a coumarin-substitued ylid, the P atom is linked to three benzene rings and a planar coumarin moiety via a methyl­enecarbonyl group. The bond lengths in the P=C–C=O fragment clearly indicate a delocalized system involving the olefinic and carbonyl bonds. The mol­ecular structure is stabilized by an intra­molecular C—H⋯O inter­action that results in an S7 graph-set ring motif. In the crystal, mol­ecules are linked into a three-dimensional framework by C—H⋯O hydrogen bonds. PMID:23424524

  13. A novel high-performance high-frequency SOI MESFET by the damped electric field

    NASA Astrophysics Data System (ADS)

    Orouji, Ali A.; Khayatian, Ahmad; Keshavarzi, Parviz

    2016-06-01

    In this paper, we introduce a novel silicon-on-insulator (SOI) metal-semiconductor field-effect-transistor (MESFET) using the damped electric field (DEF). The proposed structure is geometrically symmetric and compatible with common SOI CMOS fabrication processes. It has two additional oxide regions under the side gates in order to improve DC and RF characteristics of the DEF structure due to changes in the electrical potential, the electrical field distributions, and rearrangement of the charge carriers. Improvement of device performance is investigated by two-dimensional and two-carrier simulation of fundamental parameters such as breakdown voltage (VBR), drain current (ID), output power density (Pmax), transconductance (gm), gate-drain and gate-source capacitances, cut-off frequency (fT), unilateral power gain (U), current gain (h21), maximum available gain (MAG), and minimum noise figure (Fmin). The results show that proposed structure operates with higher performances in comparison with the similar conventional SOI structure.

  14. Synthesis and structural study of 4-(2-chlorophenyl)-2-ethoxy-5,6,7,8,9,10-hexahydrocycloocta[B]pyridine-3-carbonitrile

    NASA Astrophysics Data System (ADS)

    Fathima, K. Saiadali; Vasumathi, M.; Anitha, K.

    2016-05-01

    The novel organic material C20H21ClN2O was synthesized by One-Pot synthesis method and the single crystals were grown by slow evaporation solution growth technique. The crystal structure was elucidated by subjecting the grown crystals to the single crystal x-ray diffraction analysis and was refined by full matrix least-squares method to R=0.039 for 2746 reflections. Crystal system of the grown crystal was found to be monoclinic with the space group P21/a and a=9.196(4) Å, b=13.449(4) Å, c=14.818(4) Å, β= 101.542(3)°, V=1795.6(11) Å3 and Z=4. In this crystal structure, cyclooctanone prefers to reside in a chair-boat conformation. The structure is stabilized by attractive molecular force such as CH/π interaction called hydrophobic interaction.

  15. On the Hodge structure of elliptically fibered Calabi-Yau threefolds

    NASA Astrophysics Data System (ADS)

    Taylor, Washington

    2012-08-01

    The Hodge numbers of generic elliptically fibered Calabi-Yau threefolds over toric base surfaces fill out the "shield" structure previously identified by Kreuzer and Skarke. The connectivity structure of these spaces and bounds on the Hodge numbers are illuminated by considerations from F-theory and the minimal model program. In particular, there is a rigorous bound on the Hodge number h 21 ≤ 491 for any elliptically fibered Calabi-Yau threefold. The threefolds with the largest known Hodge numbers are associated with a sequence of blow-ups of toric bases beginning with the Hirzebruch surface {{F}_{{12}}} and ending with the toric base for the F-theory model with largest known gauge group.

  16. Three bright bolides in Kiev sky on 29 March 2013

    NASA Astrophysics Data System (ADS)

    Churyumov, K. I.; Vidmachenko, A. P.; Steklov, A. F.; Steklov, E. A.

    2013-08-01

    On March 29, 2013 during less 22 seconds the citizens of the capital of Ukraine Kiev were witnesses of three unique phenomenon of re-entry into the Earth's atmosphere of three meteoroids or possible of three fragments of one body of extraterrestrial origin; Kyiv local time sequential photographs are 16h21m56s, 16h22m04s, 16h22m16s LT. The fourth panoramic picture referres to 16h25m32s LT (Fig 1). Pictures were obtained by Egor Steklov - a pupil of the Lyceum "Logos". All three phenomena were accompanied by a noticeable increasing noise. Slow flowing traces across the sky does not exclude artificial origin of the samples

  17. 1,3,5-Tris(4-meth-oxy-phen-yl)-1,3,5-triazinane-2,4,6-trione.

    PubMed

    Fang, Li; Li, Feifei; Luo, Xuemei

    2014-02-01

    The complete mol-ecule of the title compound, C24H21N3O6, is generated by the application of threefold rotation symmetry about an axis perpendicular to the central ring. The mol-ecule exhibits a propeller-like shape. The dihedral angle between each benzene ring and the heterocyclic ring is 74.0 (1)°. The mol-ecules pack with no specific inter-molecular inter-actions between them. The SQUEEZE procedure in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155] was used to model disordered solvent mol-ecules, presumed to be acetone; the calculated unit-cell data do not take into account the presence of these. PMID:24764847

  18. Oxycodone N-oxide.

    PubMed

    Sonar, Vijayakumar N; Parkin, Sean; Crooks, Peter A

    2012-11-01

    The title compound, (5R,9R,13S,14S,17R)-14-hydroxy-3-methoxy-17-methyl-4,5-epoxymorphinan-6-one N-oxide, C(18)H(21)NO(5), has been prepared in a diastereomerically pure form by the reaction of oxycodone with 3-chloroperbenzoic acid and subsequent crystallization of the product from chloroform. The crystal packing shows that the molecule exhibits intramolecular O-H···O [D···A = 2.482 (2) Å] hydrogen bonding. In addition, there are weak intermolecular C-H...O interactions which, along with van der Waals forces, stabilize the structure. The new chiral center at the 17-position is demonstrated to be R.

  19. Structure-Triggered High Quantum Yield Luminescence and Switchable Dielectric Properties in Manganese(II) Based Hybrid Compounds.

    PubMed

    Wang, Zhong-Xia; Li, Peng-Fei; Liao, Wei-Qiang; Tang, Yuanyuan; Ye, Heng-Yun; Zhang, Yi

    2016-04-01

    Two new manganese(II) based organic-inorganic hybrid compounds, C11H21Cl3MnN2 (1) and C11H22Cl4MnN2 (2), with prominent photoluminescence and dielectric properties were synthesized by solvent modulation. Compound 1 with novel trigonal bipyramidal geometry exhibits bright red luminescence with a lifetime of 2.47 ms and high quantum yield of 35.8 %. Compound 2 with tetrahedral geometry displays intense long-lived (1.54 ms) green light emission with higher quantum yield of 92.3 %, accompanied by reversible solid-state phase transition at 170 K and a distinct switchable dielectric property. The better performance of 2 results from the structure, including a discrete organic cation moiety and inorganic metal anion framework, which gives the cations large freedom of motion.

  20. Diphen­yl[2-(2-pyridylamino­meth­yl)phen­yl]phosphine oxide

    PubMed Central

    Hernández-Ortega, Simón; Cuenu Cabeza, Fernando; Cabrera-Ortiz, Armando

    2010-01-01

    The title compound, C24H21N2OP, was obtained by reacting 2-amino­pyridine and 2-(diphenyl­phosphin­yl)benzaldehyde in ethanol. It crystallizes with two crystallographically independent mol­ecules in the asymmetric unit. The amino­pyridine units and the benzene ring bonded to the phosphine oxide P atom form dihedral angles of 88.58 (7) and 82.47 (9)° in the two mol­ecules. The crystal structure displays strong N—H⋯O and weak C—H⋯O hydrogen bonds along the b axis and C—H⋯π aromatic intra- and inter­molecular inter­actions. PMID:21579222

  1. Genetic evolution of bacteriophage. I. Hybrids between unrelated bacteriophages P22 and Fels 2.

    PubMed

    Yamamoto, N

    1969-01-01

    A new bacteriophage species, designated F22, was isolated from phage P22 stocks grown on Salmonella typhimurium Q1 lysogenic for Fels 2 at a frequency of less than 10(-11). P22 has a very short tail with a hexagonal base plate and six spikes. Phage Fels 2 is morphologically similar to E. coli T-even phages, having a long tail with a contractile sheath and carrying no genetic region related to P22. Phage F22 is morphologically and serologically indistinguishable from Fels 2, but carries the c(c(1), c(2), and c(3)) markers of P22. The color markers h(21), g, and m(3) of P22 do not appear in F22. Thus, F22 is evidently a recombinant between the unrelated bacteriophages P22 and Fels 2. The recombination between unrelated bacteriophages could play an important role in the evolution of bacteriophages.

  2. Crystal structure of zwitterionic 2-[bis­(2-meth­oxy­phen­yl)phosphanium­yl]-4-methyl­benzene­sulfonate monohydrate di­chloro­methane monosolvate

    PubMed Central

    Zhang, Hongyang; Feng, Ge; Filatov, Alexander S.; Jordan, Richard F.

    2016-01-01

    In the title compound, C21H21O5PS·H2O·CH2Cl2, the phospho­nium–sulfonate zwitterion has the acidic H atom located on the P atom rather than the sulfonate group. The S—O bond lengths [1.4453 (15)–1.4521 (14) Å] are essentially equal. In the crystal, the water mol­ecules bridge two zwitterions via Owater—H⋯Osulfonate hydrogen bonds into a centrosymmetric dimer. The dimers are further linked by weak CAr­yl—H⋯Osulfonate hydrogen bonds into chains extending along [100]. The PH+ group is not involved in inter­molecular inter­actions. PMID:26958395

  3. Crystal structure of (E)-2-[(2S,5R)-2-isopropyl-5-methyl­cyclo­hexyl­idene]hydrazine-1-carbo­thio­amide

    PubMed Central

    de Oliveira, Adriano Bof; Beck, Johannes; Daniels, Jörg; de Farias, Renan Lira; de Godoy Netto, Adelino Vieira

    2014-01-01

    The title compound, C11H21N3S, consists of a menthone moiety attached to an extended thio­semicarbazone group with the N—N—C—N torsion angle being 11.92 (16)°. The cyclo­hexane ring has a chair conformation and the conformation about the C=N bond is E. In the crystal, mol­ecules are linked via pairs of N—H⋯S hydrogen bonds, forming chains along the a axis. The absolute structure could be assigned with reference to the starting material, i.e. enanti­opure (−)-menthone [Flack parameter = 0.05 (5)]. PMID:25309244

  4. dc and microwave performance of a 0.1-micron gate InAs/In(0.52)Al(0.48)As MODFET

    NASA Astrophysics Data System (ADS)

    Yang, D.; Chen, Y. C.; Brock, T.; Bhattacharya, Pallab K.

    1992-06-01

    The performance characteristics of 0.1-micron gate InAs/In(0.52)Al(0.48)As MODFETs grown by molecular beam epitaxy are measured and analyzed. The transistors are characterized by measured g sub m (max) = 840 mS/mm, f sub T = 128 GHz, and a very high current carrying capability, e.g., I sub dss = 934 mA/mm at V sub gs = 0.4 V and V sub ds = 2.7 V. The value of f sub T is estimated from extrapolation of the current gain (H21) at a -6-dB/octave rolloff. This is the first report on the microwave characteristics of an InAs-channel MODFET and establishes the superiority of this heterostructure system.

  5. Tris(tri-o-tolyl phosphite-κP)nickel: a coordinatively unsaturated nickel(0) complex.

    PubMed

    Kampmann, Sven S; Skelton, Brian W; Wild, Duncan A; Koutsantonis, George A; Stewart, Scott G

    2015-03-01

    A previously reported complex, [Ni(C(21)H(21)O(3)P)(3)] or Ni[P(O-o-tolyl(3))(3)] [Gosser & Tolman (1970). Inorg. Chem. 9, 2350-2353], crystallized in the monoclinic space group C2/c, and its solid-state structure was determined. The Ni(0) atom adopts an essentially trigonal-planar geometry as a consequence of the steric congestion of the ligands. Three of the phenoxy rings on two phosphite ligands were modelled as being disordered over two sets of sites, and the occupancy factors were set at 0.5 after trial refinement and intramolecular contact considerations. The exact ligand cone angle has been calculated to be 163.6°. PMID:25734847

  6. Circadian response of annual weeds to glyphosate and glufosinate.

    PubMed

    Martinson, Krishona B; Sothern, Robert B; Koukkari, Willard L; Durgan, Beverly R; Gunsolus, Jeffrey L

    2002-03-01

    Five field experiments were conducted in 1998 and 1999 in Minnesota to examine the influence of time of day efficacy of glyphosate [N-(phosphonomethyl)glycine] and glufosinate [2-amino-4-(hydroxymethyl-phosphinyl)butanoic acid] applications on the control of annual weeds. Each experiment was designed to be a randomized complete block with four replications using plot sizes of 3 x 9 m. Glyphosate and glufosinate were applied at rates of 0.421 kg ae/ha and 0.292 kg ai/ha, respectively, with and without an additional adjuvant that consisted of 20% nonionic surfactant and 80% ammonium sulfate. All treatments were applied with water at 94 L/ha. Times of day for the application of herbicide were 06:00h, 09:00h, 12:00h, 15:00h, 18:00h, 21:00h, and 24:00h. Efficacy was evaluated 14 d after application by visual ratings. At 14 d, a circadian response to each herbicide was found, with greatest annual weed control observed with an application occurring between 09:00h and 18:00h and significantly less weed control observed with an application at 06:00h, 21:00h, or 24:00h. The addition of an adjuvant to both herbicides increased overall efficacy, but did not overcome the rhythmic time of day effect. Results of the multiple regression analysis showed that after environmental temperature, time of day was the second most important predictor of percent weed kill. Thus, circadian timing of herbicide application significantly influenced weed control with both glyphosate and glufosinate.

  7. Profile of Shiga toxin-producing Escherichia coli strains isolated from dogs and cats and genetic relationships with isolates from cattle, meat and humans.

    PubMed

    Bentancor, A; Rumi, M V; Carbonari, C; Gerhardt, E; Larzábal, M; Vilte, D A; Pistone-Creydt, V; Chinen, I; Ibarra, C; Cataldi, A; Mercado, E C

    2012-05-01

    Pets can be reservoirs of Shiga toxin-producing Escherichia coli (STEC) strains. The aim of this study was to examine nine strains belonging to several serotypes (O91:H21, O91:H16, O178:H19, O8:H19, O22:H8, O22:HNT, ONT:H8), previously recovered from cats or dogs. To this end, we assessed a set of additional virulence genes (stx(2) subtype, subAB, ehxA, eae and saa), cytotoxic activity, and genetic relationships with strains isolated from cattle, meat and humans using pulsed-field gel electrophoresis (PFGE). Most of the isolates carried the stx(2) and/or stx(2vh-b) sequences, while only the O91:H21 isolate presented the mucus-activatable stx(2d) variant, as confirmed by sequencing the genes of subunits A and B. All the strains showed cytotoxic activity in cultured cells. One of the two O178:H19, selected for its high level of cytotoxicity in Vero cells, showed the ability to cause functional alterations in the human colon mucosa in vitro. None of the strains possessed the subAB, eae or saa genes and only the strains belonging to serotype O8:H19 carried the ehxA gene. The isolates shared 90-100% similarity by PFGE to epidemiologically unrelated strains of the corresponding serotypes recovered from cattle, meat or humans. Our results demonstrate that dogs and cats may have a role in the infection of humans by STEC, probably serving as a vehicle for bovine strains in the cycle of human infection, and thus emphasize the health risks for owners and their families.

  8. Low-dose carbon ion irradiation effects on DNA damage and oxidative stress in the mouse testis

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Long, Jing; Zhang, Luwei; Zhang, Hong; Liu, Bin; Zhao, Weiping; Wu, Zhehua

    2011-01-01

    To investigate the effects of low-dose carbon ion irradiation on reproductive system of mice, the testes of outbred Kunming strain mice were whole-body irradiated with 0, 0.05, 0.1, 0.5 and 1 Gy, respectively. We measured DNA double-strand breaks (DNA DSBs) and oxidative stress parameters including malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, and testis weight and sperm count at 12 h, 21 d and 35 d after irradiation in mouse testis. At 12 h postirradiation, a significant increase in DNA DSB level but no pronounced alterations in MDA content or SOD activity were observed in 0.5 and 1 Gy groups compared with the control group. At 21 d postirradiation, there was a significant reduction in sperm count and distinct enhancements of DSB level and MDA content in 0.5 and 1 Gy groups in comparison with control. At 35 d postirradiation, the levels of DNA DSBs and MDA, and SOD activity returned to the baseline except for the MDA content in 1 Gy (P < 0.05), while extreme falls of sperm count were still observed in 0.5 (P < 0.01) and 1 Gy (P < 0.01) groups. For the 0.05 or 0.1 Gy group, no differences were found in DNA DSB level and MDA content between control and at 12 h, 21 d and 35 d after irradiation, indicating that lower doses of carbon ion irradiation have no significant influence on spermatogenesis processes. In this study, male germ cells irradiated with over 0.5 Gy of carbon ions are difficult to repair completely marked by the sperm count. Furthermore, these data suggest that the deleterious effects may be chronic or delayed in reproductive system after whole-body exposure to acute high-dose carbon ions.

  9. Functional studies of the gene slr2049 from Synechocystis sp. PCC6803 and its site-directed mutation.

    PubMed

    Liu, Bingjun; Chen, Sili; Zhang, Lei

    2015-06-01

    Phycobiliprotein is a homologous family of light-harvesting chromoproteins existing in cyanobacteria, red algae and cryptophytes. Phycobiliprotein is made up of phycobilin and its corresponding apophycobiliprotein, and they are covalently linked by the thioether bond with the bilin lyase. Using the software BLAST, we have found gene slr2049 in Synechocystis sp. PCC6803 homologous to the biliprotein lyase gene cpeS. This paper investigates the protein expressed by gene slr2049 to find the enzymatic activity characteristics. We cloned slr2049 and its related genes cpcB, ho1, and pcyA which are linked with the synthesis of phycocyanin. Special amino acid mutagenesis was performed on slr2049 to construct eight mutants slr2049 (H21S), slr2049 (L23S), slr2049 (A24S), slr2049 (F25S), slr2049 (W72L), slr2049 (G84S), slr2049 (R107S) and slr2049 (Y124S). These mutants were ligated with vectors pEDFDuet-1 and pET-23a to construct pCDF-cpcB-slr2049 wild-type, pCDF-cpcB-slr2049 mutants and pET-ho1-pcyA, for the purpose of protein expression and analysis. The results showed that the wild-type and mutants slr2049 (H21S), slr2049 (L23S), slr2049 (F25S), slr2049 (W72L), slr2049 (G84S), and slr2049 (Y124S) can catalyze CpcB to couple on PCB correctly and the products have unique spectral characteristics. However mutants slr2049 (A24S) and slr2049 (R107S) have no spectral characteristics. Thus, it is suggested that alanine at position 24 and arginine at position 107 are the active sites.

  10. Phylogenetic and molecular analysis of food-borne shiga toxin-producing Escherichia coli.

    PubMed

    Hauser, Elisabeth; Mellmann, Alexander; Semmler, Torsten; Stoeber, Helen; Wieler, Lothar H; Karch, Helge; Kuebler, Nikole; Fruth, Angelika; Harmsen, Dag; Weniger, Thomas; Tietze, Erhard; Schmidt, Herbert

    2013-04-01

    Seventy-five food-associated Shiga toxin-producing Escherichia coli (STEC) strains were analyzed by molecular and phylogenetic methods to describe their pathogenic potential. The presence of the locus of proteolysis activity (LPA), the chromosomal pathogenicity island (PAI) PAI ICL3, and the autotransporter-encoding gene sabA was examined by PCR. Furthermore, the occupation of the chromosomal integration sites of the locus of enterocyte effacement (LEE), selC, pheU, and pheV, as well as the Stx phage integration sites yehV, yecE, wrbA, z2577, and ssrA, was analyzed. Moreover, the antibiotic resistance phenotypes of all STEC strains were determined. Multilocus sequence typing (MLST) was performed, and sequence types (STs) and sequence type complexes (STCs) were compared with those of 42 hemolytic-uremic syndrome (HUS)-associated enterohemorrhagic E. coli (HUSEC) strains. Besides 59 STs and 4 STCs, three larger clusters were defined in this strain collection. Clusters A and C consist mostly of highly pathogenic eae-positive HUSEC strains and some related food-borne STEC strains. A member of a new O26 HUS-associated clone and the 2011 outbreak strain E. coli O104:H4 were found in cluster A. Cluster B comprises only eae-negative food-borne STEC strains as well as mainly eae-negative HUSEC strains. Although food-borne strains of cluster B were not clearly associated with disease, serotypes of important pathogens, such as O91:H21 and O113:H21, were in this cluster and closely related to the food-borne strains. Clonal analysis demonstrated eight closely related genetic groups of food-borne STEC and HUSEC strains that shared the same ST and were similar in their virulence gene composition. These groups should be considered with respect to their potential for human infection.

  11. Oxidative desulfurization of fuels catalyzed by Fenton-like ionic liquids at room temperature.

    PubMed

    Jiang, Yunqing; Zhu, Wenshuai; Li, Huaming; Yin, Sheng; Liu, Hua; Xie, Qingjie

    2011-03-21

    Oxidation of the sulfur-containing compounds benzothiophene (BT), dibenzothiophene (DBT), and 4,6-dimethyldibenzothiophene (4,6-DMDBT) has been studied in a desulfurization system composed of model oil, hydrogen peroxide, and different types of ionic liquids [(C(8)H(17))(3)CH(3)N]Cl/FeCl(3), [(C(8)H(17))(3)CH(3)N]Cl/CuCl(2), [(C(8)H(17))(3)CH(3)N]Cl/ZnCl(2), [(C(8)H(17))(3)CH(3)N]Cl/SnCl(2), [(C(4)H(9))(3)CH(3)N]Cl/FeCl(3), [C(10)H(21)(CH(3))(3)N]Cl/FeCl(3), [(C(10)H(21))(2)(CH(3))(2)N]Cl/FeCl(3). Deep desulfurization is achieved in the Fenton-like ionic liquid [(C(8)H(17))(3)CH(3)N]Cl/FeCl(3) at 25 °C for 1 h. The desulfurization of DBT reaches 97.9%, in consuming very low amount of [(C(8)H(17))(3)CH(3)N]Cl/FeCl(3) (only 0.702 mmol). The reaction conditions, for example, the amount of [(C(8)H(17))(3)CH(3)N]Cl/FeCl(3) or H(2)O(2), the temperature, and the molar ratio of FeCl(3) to [(C(8)H(17))(3)CH(3)N]Cl, are investigated for this system. The oxidation reactivity of the different sulfur-containing compounds is found to decrease in the order of DBT>BT>4,6-DMDBT. The desulfurization system can be recycled six times without significant decrease in activity. The sulfur level of FCC gasoline could be reduced from 360 ppm to 110 ppm. PMID:21394927

  12. Isolation of a lysogenic bacteriophage carrying the stx(1(OX3)) gene, which is closely associated with Shiga toxin-producing Escherichia coli strains from sheep and humans.

    PubMed

    Koch, C; Hertwig, S; Lurz, R; Appel, B; Beutin, L

    2001-11-01

    A specific PCR for the detection of a variant of the gene encoding Shiga toxin 1 (stx(1)) called stx(1(OX3)) (GenBank accession no. Z36901) was developed. The PCR was used to investigate 148 Stx(1)-producing Escherichia coli strains from human patients (n = 72), cattle (n = 27), sheep (n = 48), and a goat (n = 1) for the presence of the stx(1(OX3)) gene. The stx(1(OX3)) gene was present in 38 Shiga toxin-producing E. coli (STEC) strains from sheep belonging to serogroups O5, O125, O128, O146, and OX3 but was absent from Stx(1)-positive ovine STEC O91 strains. The stx(1(OX3)) gene was also detected in 22 STEC strains from humans with nonbloody diarrhea and from asymptomatic excreters. Serotypes O146:H21 and O128:H2 were most frequently associated with stx(1(OX3))-carrying STEC from sheep and humans. In contrast, Stx(1)-producing STEC strains from cattle and goats and 50 STEC strains from humans were all negative for the stx(1(OX3)) gene. The stx(1(OX3))-negative strains belonged to 13 serotypes which were different from those of the stx(1(OX3))-positive STEC strains. Moreover, the stx(1(OX3)) gene was not associated with STEC belonging to enterohemorrhagic E. coli (EHEC) serogroups O26, O103, O111, O118, O145, and O157. A bacteriophage carrying the stx(1(OX3)) gene (phage 6220) was isolated from a human STEC O146:H21 strain. The phage was able to lysogenize laboratory E. coli K-12 strain C600. Phage 6220 shared a similar morphology and a high degree of DNA homology with Stx(2)-encoding phage 933W, which originates from EHEC O157. In contrast, few similarities were found between phage 6220 and Stx(1)-encoding bacteriophage H-19B from EHEC O26.

  13. Functional studies of the gene slr2049 from Synechocystis sp. PCC6803 and its site-directed mutation.

    PubMed

    Liu, Bingjun; Chen, Sili; Zhang, Lei

    2015-06-01

    Phycobiliprotein is a homologous family of light-harvesting chromoproteins existing in cyanobacteria, red algae and cryptophytes. Phycobiliprotein is made up of phycobilin and its corresponding apophycobiliprotein, and they are covalently linked by the thioether bond with the bilin lyase. Using the software BLAST, we have found gene slr2049 in Synechocystis sp. PCC6803 homologous to the biliprotein lyase gene cpeS. This paper investigates the protein expressed by gene slr2049 to find the enzymatic activity characteristics. We cloned slr2049 and its related genes cpcB, ho1, and pcyA which are linked with the synthesis of phycocyanin. Special amino acid mutagenesis was performed on slr2049 to construct eight mutants slr2049 (H21S), slr2049 (L23S), slr2049 (A24S), slr2049 (F25S), slr2049 (W72L), slr2049 (G84S), slr2049 (R107S) and slr2049 (Y124S). These mutants were ligated with vectors pEDFDuet-1 and pET-23a to construct pCDF-cpcB-slr2049 wild-type, pCDF-cpcB-slr2049 mutants and pET-ho1-pcyA, for the purpose of protein expression and analysis. The results showed that the wild-type and mutants slr2049 (H21S), slr2049 (L23S), slr2049 (F25S), slr2049 (W72L), slr2049 (G84S), and slr2049 (Y124S) can catalyze CpcB to couple on PCB correctly and the products have unique spectral characteristics. However mutants slr2049 (A24S) and slr2049 (R107S) have no spectral characteristics. Thus, it is suggested that alanine at position 24 and arginine at position 107 are the active sites. PMID:25791490

  14. Profile of Shiga toxin-producing Escherichia coli strains isolated from dogs and cats and genetic relationships with isolates from cattle, meat and humans.

    PubMed

    Bentancor, A; Rumi, M V; Carbonari, C; Gerhardt, E; Larzábal, M; Vilte, D A; Pistone-Creydt, V; Chinen, I; Ibarra, C; Cataldi, A; Mercado, E C

    2012-05-01

    Pets can be reservoirs of Shiga toxin-producing Escherichia coli (STEC) strains. The aim of this study was to examine nine strains belonging to several serotypes (O91:H21, O91:H16, O178:H19, O8:H19, O22:H8, O22:HNT, ONT:H8), previously recovered from cats or dogs. To this end, we assessed a set of additional virulence genes (stx(2) subtype, subAB, ehxA, eae and saa), cytotoxic activity, and genetic relationships with strains isolated from cattle, meat and humans using pulsed-field gel electrophoresis (PFGE). Most of the isolates carried the stx(2) and/or stx(2vh-b) sequences, while only the O91:H21 isolate presented the mucus-activatable stx(2d) variant, as confirmed by sequencing the genes of subunits A and B. All the strains showed cytotoxic activity in cultured cells. One of the two O178:H19, selected for its high level of cytotoxicity in Vero cells, showed the ability to cause functional alterations in the human colon mucosa in vitro. None of the strains possessed the subAB, eae or saa genes and only the strains belonging to serotype O8:H19 carried the ehxA gene. The isolates shared 90-100% similarity by PFGE to epidemiologically unrelated strains of the corresponding serotypes recovered from cattle, meat or humans. Our results demonstrate that dogs and cats may have a role in the infection of humans by STEC, probably serving as a vehicle for bovine strains in the cycle of human infection, and thus emphasize the health risks for owners and their families. PMID:22119188

  15. On the Significance of Bacterial triterpenic Biomarkers in Sediments

    NASA Astrophysics Data System (ADS)

    Rohmer, M.

    2004-12-01

    Triterpenic biomarkers are ubiquitous in the organic matter of sediments. Bacterial contribution is essential for several series. Despite the numerous investigations performed over the last decades, little is known about the distribution of triterpenoids in Eubacteria. An updated survey of triterpene distribution in Eubacteria points out a much broader diversity of the structures than expected ten years ago. Hopanoids characterized by their C35 skeleton resulting from a carbon/carbon linkage between the triterpene hopane skeleton and a D-ribose derivative are the most frequent ones. Their distribution cannot be readily interpreted and may result from lateral gene transfer. Many groups, such as strict anaerobes, are underrepresented in the screenings, mainly because of the complex techniques required for their growth. Most of the bacterial hopanoids belong to the (17α H,21β H) series, corresponding to the stereochemistry of hopanoid biomarkers from non-mature sediments. (17β H,21α H)- and especially (17α ,21β H)-hopanoids are derived from the former series via diagenesis and maturation of the organic matter. Both series were, however, recently found in widespread soil bacteria (Frankia spp., Geodermatophilus spp.) questioning at least partially their significance as maturation indicators. Quasi-hopanoids with the gammacerane skeleton were first found in ciliate protozoa. They are also present in high concentrations in the phylogenetically related bacteria Rhodopseudomonas palustris and all Bradyrhizobium spp. In all closely investigated hopanoid producing bacteria, a complex mixture of triterpene hydrocarbons accompanied in small amounts hop-22(29)-ene. They include pentacyclic triterpenes (rearranged hopenes, fernenes) as well as tetracyclic triterpenes (dammaradienes, euphadienes) and result from a lack of strict control of the cyclization process by the squalene/hopene cyclase. Triterpenoids related to sterol biosynthesis (lanosterol, cycloartenol) have

  16. Molecular and serotyping characterization of shiga toxogenic Escherichia coli associated with food collected from Saudi Arabia

    PubMed Central

    Al-Zogibi, Onizan G.; Mohamed, Moussa I.; Hessain, Ashgan M.; El-Jakee, Jakeen K.; Kabli, Saleh A.

    2015-01-01

    Shiga toxin-producing Escherichia coli (STEC) strains are considered as one of the major food-borne disease agents in humans worldwide. STEC strains, also called verotoxin-producing E. coli strains. The objectives of the present study were serotyping and molecular characterization of shiga toxigenic E. coli associated with raw meat and milk samples collected from Riyadh, Saudi Arabia. A total of 540 milk samples were collected from 5 dairy farms and 150 raw meat samples were collected from different abattoirs located in Riyadh, Saudi Arabia. E. coli were recovered from 86 milk samples (15.93%), serotyping of E. coli isolates revealed, 26 (4.81%) strains O157: H7, 23 (4.26%) strains O111, 20 (3.70%) strains O113: H21, 10 (1.85%) strains O22: H8 and 7 (1.3%) strains O172: H21. Meanwhile, 17 (11.33%) strains of E. coli were recovered from raw meat samples, serotyping of E. coli isolates revealed, 6 (4%) strains O157: H7, 5 (3.33%) strains O111 and 4 (2.67%) strains O174: H2 and only two (1.33%) strains were identified as O22: H8. Shiga toxin2 was detected in 58 (67.44%) serotypes of E. coli recovered from milk samples and 16 (94.12%) serotypes of E. coli recovered from meat samples, while intimin gene was detected in 38 (44.186%) serotypes of E. coli recovered from milk samples and in 10 (58.82%) serotypes of E. coli recovered from meat samples. The results of this study revealed the efficiency of combination between serotyping and molecular typing of E. coli isolates recovered from food of animal origin for rapid detection and characterization of STEC. PMID:26150750

  17. Synthesis, mesomorphic properties and structural studies on 1,3,5-trisubstituted benzene-based star-shaped derivatives containing Schiff base ester as the peripheral arm

    NASA Astrophysics Data System (ADS)

    Ooi, Yew-Hong; Yeap, Guan-Yeow; Takeuchi, Daisuke

    2013-11-01

    Six new symmetrical three-armed star-shaped liquid crystals comprising phloroglucinol (1,3,5-trihydroxybenzene) as a core center and three Schiff base ester as the mesogenic arms have been synthesized. Their molecular structures were supported by spectroscopic techniques (FT-IR, 1H NMR, 13C NMR and two dimensional COSY, HMQC and HMBC). Each of the member differs in the length of the terminal alkyl chain (Rsbnd COOsbnd where R = C8H17, C10H21, C12H25, C14H29, C16H33, C18H37). All the star-shaped mesogens are found to be monotropic smectogens with the short chain derivative (R = C8H17) exhibits only smectic A phase. While both the smectic A and smectic C phases are common for the derivatives with C10H21sbnd C16H33 alkyl chain, the member with C18H37 shows only smectic C phase. Further investigation by X-ray diffraction confirms the smectic phase of the materials whereby two sharp reflections at 28.8 Å and 57.3 Å recorded via small angle in a ratio of 1:2 indicate unambiguously the presence of layered structure and a diffused scattering via the wide angle (4.5 Å) indicates a liquid-like order within the smectic layer. Increasing the length of terminal flexible chain has influenced remarkably the thermal and phase stability of the titled compounds. Besides, the liquid crystalline properties of all intermediary ω-brominated Schiff base ester prior joining to the benzene core were also evaluated.

  18. Diverse Virulence Gene Content of Shiga Toxin-Producing Escherichia coli from Finishing Swine

    PubMed Central

    Fratamico, Pina M.; Bagi, Lori; Delannoy, Sabine; Fach, Patrick; Manning, Shannon D.; Funk, Julie A.

    2014-01-01

    Shiga toxin-producing Escherichia coli (STEC) infections are a critical public health concern because they can cause severe clinical outcomes, such as hemolytic uremic syndrome, in humans. Determining the presence or absence of virulence genes is essential in assessing the potential pathogenicity of STEC strains. Currently, there is limited information about the virulence genes carried by swine STEC strains; therefore, this study was conducted to examine the presence and absence of 69 virulence genes in STEC strains recovered previously from finishing swine in a longitudinal study. A subset of STEC strains was analyzed by pulsed-field gel electrophoresis (PFGE) to examine their genetic relatedness. Swine STEC strains (n = 150) were analyzed by the use of a high-throughput real-time PCR array system, which included 69 virulence gene targets. Three major pathotypes consisted of 16 different combinations of virulence gene profiles, and serotypes were determined in the swine STEC strains. The majority of the swine STEC strains (n = 120) belonged to serotype O59:H21 and carried the same virulence gene profile, which consisted of 9 virulence genes: stx2e, iha, ecs1763, lpfAO113, estIa (STa), ehaA, paa, terE, and ureD. The eae, nleF, and nleH1-2 genes were detected in one swine STEC strain (O49:H21). Other genes encoding adhesins, including iha, were identified (n = 149). The PFGE results demonstrated that swine STEC strains from pigs raised in the same finishing barn were closely related. Our results revealed diverse virulence gene contents among the members of the swine STEC population and enhance understanding of the dynamics of transmission of STEC strains among pigs housed in the same barn. PMID:25107960

  19. Secretion of electrolytes, protein and urea by the mandibular gland of the common wombat (Vombatus ursinus).

    PubMed

    Beal, A M

    1995-01-01

    Saliva was collected from the mandibular glands of anaesthetized common wombats (Vombatus ursinus) to ascertain maximal flow rates, salivary composition and possible adaptations, particularly PO4(3-) secretion, to assist digestion. After temporary catheterization of the main duct through its oral opening, salivary secretion was evoked at flow rates ranging from 0.02 +/- 0.002 (+/- SEM) ml.min-1 (0.7 +/- 0.07 microliter.min-1.kg body weight-1) to 0.4 +/- 0.05 ml.min-1 (14 +/- 1.9 microliters.min-1.kg body weight-1) by ipsilateral intracarotid infusion of acetylcholine. The [Na+] (15 +/- 5.1 to 58 +/- 8.6 mmol.l-1) and [HCO3-] (35 +/- 1.9 to 60 +/- 1.9 mmol.l-1) were positively correlated with salivary flow rate. The [K+] (58 +/- 5.2 to 30 +/- 2.4 mmol.l-1), [Ca2+] (10.4 +/- 1.67 to 4.1 +/- 0.44 mmol.l-1), [Mg2+] (0.94 +/- 0.137 to 0.17 +/- 0.032 mmol.l-1), [Cl-] (71 +/- 9.2 to 45 +/- 6.0 mmol.l-1), [urea] (9.3 +/- 0.79 to 5.1 +/- 0.54 mmol.l-1), H+ activity (29 +/- 1.6 to 17 +/- 1.6 nEq.l-1) and amylase activity (251 +/- 57.4 to 92 +/- 23.3 mu kat.l-1) were negatively correlated with flow. Both concentration and osmolality fell with increasing flow at the lower end of the flow range but osmolality always increased again by maximal flow whereas the relation between protein and flow was not consistent at the higher levels of flow and stimulation. Salivary [PO4(3+)] was not correlated with flow and at 3-14% of the plasma concentration was extremely low.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7738231

  20. Secretion of electrolytes, protein and urea by the mandibular gland of the common wombat (Vombatus ursinus).

    PubMed

    Beal, A M

    1995-01-01

    Saliva was collected from the mandibular glands of anaesthetized common wombats (Vombatus ursinus) to ascertain maximal flow rates, salivary composition and possible adaptations, particularly PO4(3-) secretion, to assist digestion. After temporary catheterization of the main duct through its oral opening, salivary secretion was evoked at flow rates ranging from 0.02 +/- 0.002 (+/- SEM) ml.min-1 (0.7 +/- 0.07 microliter.min-1.kg body weight-1) to 0.4 +/- 0.05 ml.min-1 (14 +/- 1.9 microliters.min-1.kg body weight-1) by ipsilateral intracarotid infusion of acetylcholine. The [Na+] (15 +/- 5.1 to 58 +/- 8.6 mmol.l-1) and [HCO3-] (35 +/- 1.9 to 60 +/- 1.9 mmol.l-1) were positively correlated with salivary flow rate. The [K+] (58 +/- 5.2 to 30 +/- 2.4 mmol.l-1), [Ca2+] (10.4 +/- 1.67 to 4.1 +/- 0.44 mmol.l-1), [Mg2+] (0.94 +/- 0.137 to 0.17 +/- 0.032 mmol.l-1), [Cl-] (71 +/- 9.2 to 45 +/- 6.0 mmol.l-1), [urea] (9.3 +/- 0.79 to 5.1 +/- 0.54 mmol.l-1), H+ activity (29 +/- 1.6 to 17 +/- 1.6 nEq.l-1) and amylase activity (251 +/- 57.4 to 92 +/- 23.3 mu kat.l-1) were negatively correlated with flow. Both concentration and osmolality fell with increasing flow at the lower end of the flow range but osmolality always increased again by maximal flow whereas the relation between protein and flow was not consistent at the higher levels of flow and stimulation. Salivary [PO4(3+)] was not correlated with flow and at 3-14% of the plasma concentration was extremely low.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Helix-forming tendencies of amino acids depend on the restrictions of side-chain rotamer conformations: crystal structure of the tripeptide GAI in two crystalline forms.

    PubMed

    Go, K; Chaturvedi, S; Parthasarathy, R

    1992-02-01

    In our attempts to design crystalline alpha-helical peptides, we synthesized and crystallized GAI (C11H21N3O4) in two crystal forms, GAI1 and GAI2. Form 1 (GAI1) Gly-L-Ala-L-Ile (C11H21N3O4.3H2O) crystals are monoclinic, space group P2(1) with a = 8.171(2), b = 6.072(4), c = 16.443(4) A, beta = 101.24(2) degrees, V = 800 A3, Dc = 1.300 g cm-3 and Z = 2, R = 0.081 for 482 reflections. Form 2 (GAI2) Gly-L-Ala-L-Ile (C11H21N3O4.1/2H2O) is triclinic, space group P1 with a = 5.830(1), b = 8.832(2), c = 15.008(2) A, alpha = 102.88(1), beta = 101.16(2), gamma = 70.72(2) degrees, V = 705 A3, Z = 2, Dc = 1.264 g cm-3, R = 0.04 for 2582 reflections. GAI1 is isomorphous with GAV and forms a helix, whereas GAI2 does not. In GAI1, the tripeptide molecule is held in a near helical conformation by a water molecule that bridges the NH3+ and COO- groups, and acts as the fourth residue needed to complete the turn by forming two hydrogen bonds. Two other water molecules form intermolecular hydrogen bonds in stabilizing the helical structure so that the end result is a column of molecules that looks like an incipient alpha-helix. GAI2 imitates a cyclic peptide and traps a water molecule. The conformation angles chi 11 and chi 12 for the side chain are (-63.7 degrees, 171.1 degrees) for the helical GAI1, and (-65.1 degrees, 58.6 degrees) and (-65.0 degrees, 58.9 degrees) for the two independent nonhelical molecules in GAI2; in GAI1, both the C gamma atoms point away from the helix, whereas in GAI2 the C gamma atom with the g+ conformation points inward to the helix and causes sterical interaction with atoms in the adjacent peptide plane. From these results, it is clear that the helix-forming tendencies of amino acids correlate with the restrictions of side-chain rotamer conformations. Both the peptide units in GAI1 are trans and show significant deviation from planarity [omega 1 = -168(1) degrees; omega 2 = -171(1) degrees] whereas both the peptide units in both the molecules A and B

  2. Subtilase contributes to the cytotoxicity of a Shiga toxin-producing Escherichia coli strain encoding three different toxins.

    PubMed

    Hauser, Elisabeth; Bruederle, Matthias; Reich, Carolin; Bruckbauer, Annette; Funk, Joschua; Schmidt, Herbert

    2016-01-18

    Food-borne Shiga toxin-producing Escherichia coli (STEC) O113:H21 strain TS18/08, that has previously been isolated from mixed minced meat, harbors the Shiga toxin (Stx) encoding allele stx2a, the plasmid-located subtilase cytotoxin encoding allele subAB1 and the cytolethal distending toxin type V encoding gene cdt-V. In the current study, it could be shown that each of these toxin genes was transcribed with different transcription levels at different time points by RT real time PCR under laboratory batch conditions in LB-broth. The transcription maximum for cdt-V and subAB1 was observed after 3h while stx2a transcription was highest after 6h of incubation. During this time the mean relationship of the amount of stx2a:subAB1:cdt-V transcripts was 1:26:100. Furthermore, isogenic stx2a and cdt-V chromosomal deletion mutants were constructed to measure the contribution of SubAB1 to the overall cytotoxicity of this strain. In this context, a further copy of stx2 was detected in this strain and was also deleted. Comparing the cytotoxicity of supernatants of the resulting mutant strains TS18/08-3 (Δstx2-1Δstx2-2Δcdt-V) and TS18/08-4 (Δstx2-1Δstx2-2Δcdt-VΔsubAB1) on Vero cells demonstrated a contribution of SubAB1 to the overall cytotoxic effect while the 4-fold isogenic deletion mutant did not show any cytotoxic effect and that was comparable to the non-toxic laboratory E. coli strain C600. The cytotoxic effect could be restored by complementation with the recombinant low copy plasmid pWSK29 harboring subAB1 under the control of its own promoter. In addition, the cytotoxicity of wild type strain TS18/08 to Vero cells was in the same range as the EHEC O157:H7 strain EDL933. Therefore, food-borne STEC O113:H21 strain TS18/08 can be considered as a putative human pathogen.

  3. Crystal structures of four δ-keto esters and a Cambridge Structural Database analysis of cyano-halogen interactions.

    PubMed

    Kamal, Kulsoom; Maurya, Hardesh K; Gupta, Atul; Vasudev, Prema G

    2015-10-01

    The revived interest in halogen bonding as a tool in pharmaceutical cocrystals and drug design has indicated that cyano-halogen interactions could play an important role. The crystal structures of four closely related δ-keto esters, which differ only in the substitution at a single C atom (by H, OMe, Cl and Br), are compared, namely ethyl 2-cyano-5-oxo-5-phenyl-3-(piperidin-1-yl)pent-2-enoate, C19H22N2O3, (1), ethyl 2-cyano-5-(4-methoxyphenyl)-5-oxo-3-(piperidin-1-yl)pent-2-enoate, C20H24N2O4, (2), ethyl 5-(4-chlorophenyl)-2-cyano-5-oxo-3-(piperidin-1-yl)pent-2-enoate, C19H21ClN2O3, (3), and the previously published ethyl 5-(4-bromophenyl)-2-cyano-5-oxo-3-(piperidin-1-yl)pent-2-enoate, C19H21BrN2O3, (4) [Maurya, Vasudev & Gupta (2013). RSC Adv. 3, 12955-12962]. The molecular conformations are very similar, while there are differences in the molecular assemblies. Intermolecular C-H...O hydrogen bonds are found to be the primary interactions in the crystal packing and are present in all four structures. The halogenated derivatives have additional aromatic-aromatic interactions and cyano-halogen interactions, further stabilizing the molecular packing. A database analysis of cyano-halogen interactions using the Cambridge Structural Database [CSD; Groom & Allen (2014). Angew. Chem. Int. Ed. 53, 662-671] revealed that about 13% of the organic molecular crystals containing both cyano and halogen groups have cyano-halogen interactions in their packing. Three geometric parameters for the C-X...N[triple-bond]C interaction (X = F, Cl, Br or I), viz. the N...X distance and the C-X...N and C-N...X angles, were analysed. The results indicate that all the short cyano-halogen contacts in the CSD can be classified as halogen bonds, which are directional noncovalent interactions.

  4. Crystal structures of four δ-keto esters and a Cambridge Structural Database analysis of cyano-halogen interactions.

    PubMed

    Kamal, Kulsoom; Maurya, Hardesh K; Gupta, Atul; Vasudev, Prema G

    2015-10-01

    The revived interest in halogen bonding as a tool in pharmaceutical cocrystals and drug design has indicated that cyano-halogen interactions could play an important role. The crystal structures of four closely related δ-keto esters, which differ only in the substitution at a single C atom (by H, OMe, Cl and Br), are compared, namely ethyl 2-cyano-5-oxo-5-phenyl-3-(piperidin-1-yl)pent-2-enoate, C19H22N2O3, (1), ethyl 2-cyano-5-(4-methoxyphenyl)-5-oxo-3-(piperidin-1-yl)pent-2-enoate, C20H24N2O4, (2), ethyl 5-(4-chlorophenyl)-2-cyano-5-oxo-3-(piperidin-1-yl)pent-2-enoate, C19H21ClN2O3, (3), and the previously published ethyl 5-(4-bromophenyl)-2-cyano-5-oxo-3-(piperidin-1-yl)pent-2-enoate, C19H21BrN2O3, (4) [Maurya, Vasudev & Gupta (2013). RSC Adv. 3, 12955-12962]. The molecular conformations are very similar, while there are differences in the molecular assemblies. Intermolecular C-H...O hydrogen bonds are found to be the primary interactions in the crystal packing and are present in all four structures. The halogenated derivatives have additional aromatic-aromatic interactions and cyano-halogen interactions, further stabilizing the molecular packing. A database analysis of cyano-halogen interactions using the Cambridge Structural Database [CSD; Groom & Allen (2014). Angew. Chem. Int. Ed. 53, 662-671] revealed that about 13% of the organic molecular crystals containing both cyano and halogen groups have cyano-halogen interactions in their packing. Three geometric parameters for the C-X...N[triple-bond]C interaction (X = F, Cl, Br or I), viz. the N...X distance and the C-X...N and C-N...X angles, were analysed. The results indicate that all the short cyano-halogen contacts in the CSD can be classified as halogen bonds, which are directional noncovalent interactions. PMID:26422224

  5. Chemical composition of PM2.5 from two tunnels with different vehicular fleet characteristics.

    PubMed

    Cui, Min; Chen, Yingjun; Tian, Chongguo; Zhang, Fan; Yan, Caiqing; Zheng, Mei

    2016-04-15

    The chemical compositions of PM2.5 including OC, EC, water soluble ions, elements, and organic components such as polycyclic aromatic hydrocarbons (PAHs), hopanes, and steranes, emitted in Wuzushan (WZS) and Kuixinglou (KXL) tunnels were determined. WZS tunnel is a major route for diesel vehicles traveling, while KXL tunnel has limited to diesel vehicles. The results showed that the proportions of the different constituents of PM2.5 in the Wuzushan (WZS) tunnel were OC (27.7%), EC (32.1%), elements (13.9%), and water soluble ions (9.2%). Whereas the chemical profile of PM2.5 in the Kuixinglou (KXL) tunnel was OC (17.7%), EC (10.4%), elements (8.90%), and water soluble ions (8.87%). The emission factors (EFs) of PM2.5 and proportions of SO4(2-) and Pb were decreased by vehicle emission standards and fuel quality policy in China, and the higher molecular weight PAHs (4+5+6 rings) were more abundant than the lower molecular weight PAHs (2+3 rings) in the two tunnels. The proportions of 17A(H)-21B(H)-30-Norhopane and 17A(H)-21B(H)-Hopane in the hopane and sterane were not dependent on the vehicles types. In addition, specific composition profiles for PM2.5 from gasoline-fueled vehicles (GV) and diesel-fueled vehicles (DV) emissions were drafted, which indicated that OC (0.974mg·veh(-1)·km(-1)) was the most abundant component in PM2.5, followed by Fe, Cl(-), and Mg for GV. The relative proportions of the different constituents in the PM2.5 for DV were EC (35.9%), OC (27.2%), elements (12.8%), and water soluble ions (11.7%). Both the PM2.5 EFs and EC proportions in DV were higher than those in GV, and the HMW PAHs were the dominant PAHs for both GV and DV. The PM2.5 emissions from the vehicles in Yantai were 581±513tons to 1353±1197tons for GV, and 19,627±2477tons to 23,042±2887tons for DV, respectively. PMID:26808403

  6. Chemical composition of PM2.5 from two tunnels with different vehicular fleet characteristics.

    PubMed

    Cui, Min; Chen, Yingjun; Tian, Chongguo; Zhang, Fan; Yan, Caiqing; Zheng, Mei

    2016-04-15

    The chemical compositions of PM2.5 including OC, EC, water soluble ions, elements, and organic components such as polycyclic aromatic hydrocarbons (PAHs), hopanes, and steranes, emitted in Wuzushan (WZS) and Kuixinglou (KXL) tunnels were determined. WZS tunnel is a major route for diesel vehicles traveling, while KXL tunnel has limited to diesel vehicles. The results showed that the proportions of the different constituents of PM2.5 in the Wuzushan (WZS) tunnel were OC (27.7%), EC (32.1%), elements (13.9%), and water soluble ions (9.2%). Whereas the chemical profile of PM2.5 in the Kuixinglou (KXL) tunnel was OC (17.7%), EC (10.4%), elements (8.90%), and water soluble ions (8.87%). The emission factors (EFs) of PM2.5 and proportions of SO4(2-) and Pb were decreased by vehicle emission standards and fuel quality policy in China, and the higher molecular weight PAHs (4+5+6 rings) were more abundant than the lower molecular weight PAHs (2+3 rings) in the two tunnels. The proportions of 17A(H)-21B(H)-30-Norhopane and 17A(H)-21B(H)-Hopane in the hopane and sterane were not dependent on the vehicles types. In addition, specific composition profiles for PM2.5 from gasoline-fueled vehicles (GV) and diesel-fueled vehicles (DV) emissions were drafted, which indicated that OC (0.974mg·veh(-1)·km(-1)) was the most abundant component in PM2.5, followed by Fe, Cl(-), and Mg for GV. The relative proportions of the different constituents in the PM2.5 for DV were EC (35.9%), OC (27.2%), elements (12.8%), and water soluble ions (11.7%). Both the PM2.5 EFs and EC proportions in DV were higher than those in GV, and the HMW PAHs were the dominant PAHs for both GV and DV. The PM2.5 emissions from the vehicles in Yantai were 581±513tons to 1353±1197tons for GV, and 19,627±2477tons to 23,042±2887tons for DV, respectively.

  7. A comparative study of biofilm formation by Shiga toxigenic Escherichia coli using epifluorescence microscopy on stainless steel and a microtitre plate method.

    PubMed

    Rivas, Lucia; Dykes, Gary A; Fegan, Narelle

    2007-04-01

    Attachment of Shiga toxigenic Escherichia coli (STEC) to surfaces and the formation of biofilms may enhance persistence in a food processing environment and present a risk of contaminating products. Seven strains of STEC and three non-STEC strains were selected to compare two biofilm quantification methods; epifluorescence microscopy on stainless steel (SS) and a microtitre plate assay. The influence of prior growth in planktonic (nutrient broth) and sessile (nutrient agar) culture on biofilm production, as well as expression of surface structures and the possession of antigen 43 (encoded by agn43) on biofilm formation were also investigated. Biofilms were produced in diluted nutrient broth at 25 degrees C for 24 and 48 h. Curli expression was determined using congo red indicator agar, while the presence of agn43 was determined using polymerase chain reaction. No correlation was found between counts for epifluorescence microscopy on SS and the absorbance values obtained with the microtitre plate method for planktonic and sessile grown cultures. Different abilities of individual STEC strains to attach to SS and microtitre plates were found with some strains attaching better to each surface following growth in either planktonic or sessile culture. All O157 STEC strains had low biofilm counts on SS for planktonic and sessile grown cultures; however, one STEC O157:H- strain (EC516) had significantly greater (p<0.05) biofilm production on microtitre plates compared to the other O157 STEC strains. EC516 and other STEC (O174:H21 and O91:H21) strains expressing curli fimbriae were found to produce significantly greater (p<0.05) biofilms on microtitre plates compared to the non-curli expressing strains. No relationship was found between the production of type-I fimbriae, motility, agn43 and bacterial physicochemical properties (previously determined) and biofilm formation on SS or microtitre plates. Variations between the two biofilm determination methods may suggest that

  8. Microbial ecology of Bacillus thuringiensis: fecal populations recovered from wildlife in Korea.

    PubMed

    Lee, Dong-Hyun; Cha, In Hwan; Woo, Doo Sung; Ohba, Michio

    2003-07-01

    A total of 34 fecal samples, collected from 14 species of wild mammals in Korea, were examined for the occurrence of Bacillus thuringiensis. The organism was detected in 18 (53%) samples. Among the three food-habit groups, herbivorous animals yielded the highest frequency (69%) of samples positive for B. thuringiensis, followed by omnivorous animals (50%). Of the six fecal samples from carnivorous animals, only one sample contained B. thurin giensis. Among 527 isolates belonging to the Bacillus cereus - B. thuringiensis group, 43 (8%) were assigned to B. thurin giensis on the basis of the formation of parasporal inclusions. Of the 43 isolates, 13 were serologically allocated to the nine H-antigenic serotypes: H3ad (serovar sumiyoshiensis), H15 (dakota), H17/27 (tohokuensis/ mexicanensis), H19 (tochigiensis), H21 (colmeri), H29 (amagiensis), H31/49 (toguchini/muju), H42 (jinghongiensis), and H44 (higo). Other isolates were untestable or untypable by the 55 reference H antisera available. Insecticidal activity was associated with 23% of the fecal populations: three isolates killed larvae of the silkworm, Bombyx mori (Lepidoptera), and seven exhibited larvicidal activity against the mosquito, Aedes aegypti (Diptera). There was no larvicidal activity against the three lepidopterous insects: Plutella xylostella, Spodoptera exigua, and Spodoptera litura. The overall results suggest that wild animals in Korea are in contact with naturally occurring B. thuringiensis at high frequencies through the daily food intake of plants.

  9. Biodegradation of Hopane Prevents Use As Conservative Biomarker During Bioremediation of PAHs in Petroleum Contaminated Soils

    SciTech Connect

    Huesemann, Michael H.; Hausmann, Tom S.; Fortman, Timothy J.

    2003-04-01

    The pentacyclic triterpane C30 17a (H), 21b (H)-hopane, a biomarker commonly used in hydrocarbon bioremediation laboratory experiments and field studies, was found to be completely removed without the formation of the demethylated intermediate nor-hopane in a crude oil contaminated soil undergoing slurry biotreatment while PAHs such as benzo(e)pyrene were recalcitrant. The partial or complete biodegradation of hopane has also been previously reported in a few bioremediation studies and has been explored by petroleum geochemists in an effort to characterize crude oil deposits. It is currently not clear what conditions induce hopane biodegradation or biotransformation, although the use of microbial enrichment cultures appears to speed up the process. Considering that hopane is not necessarily conserved during a bioremediation study, the uncritical normalization of hydrocarbon concentrations using this biomarker can lead to incorrect estimates of biodegradation rates and extents. If hopane is found to be unstable in a particular case, other potential biomarkers such as pentahopane, oleanane, or vanadium may be used instead.

  10. Crystal structure of dimethyl 3,3′-[(4-chloro­phen­yl)methyl­ene]bis­(1H-indole-2-carboxyl­ate)

    PubMed Central

    Li, Yu-long; Sun, Hong-shun; Jiang, Hong; Xu, Ning; Xu, Hong

    2014-01-01

    In the title compound, C27H21ClN2O4, the mean planes of the two indole ring systems (r.m.s. deviations = 0.021 and 0.024 Å) are approximately perpendicular to one another, with a dihedral angle of 79.54 (12)°. The benzene ring is twisted with respect to the mean planes of the two indole ring systems at angles of 80.14 (15) and 86.30 (15)°. In the crystal, mol­ecules are linked by N—H⋯O hydrogen bonds, forming inversion dimers with an R 2 2(18) ring motif. The dimers are linked by a further N—H⋯O hydrogen bond, forming chains along [100]. There are intra- and inter­molecular C—H⋯π inter­actions present, the latter linking the chains to form a three-dimensional supra­molecular structure. PMID:25484668

  11. Constraining neutrino mass using the large-scale H I distribution in the post-reionization epoch

    NASA Astrophysics Data System (ADS)

    Pal, Ashis Kumar; Guha Sarkar, Tapomoy

    2016-07-01

    The neutral intergalactic medium in the post-reionization epoch allows us to study cosmological structure formation through the observation of the redshifted 21 cm signal and the Lyman α forest. We investigate the possibility of measuring the total neutrino mass through the suppression of power in the matter power spectrum. We investigate the possibility of measuring the neutrino mass through its imprint on the cross-correlation power spectrum of the 21 cm signal and the Lyman α forest. We consider a radio-interferometric measurement of the 21 cm signal with a SKA1-mid-like radio telescope and a BOSS-like Lyman α forest survey. A Fisher matrix analysis shows that at the fiducial redshift z = 2.5, a 10 000 h 21 cm observation distributed equally over 25 radio pointings and a Lyman α forest survey with 30 quasars lines of sights in 1deg2, allows us to measure Ων at a 3.25 per cent level. A total of 25 000 h radio-interferometric observation distributed equally over 25 radio pointings and a Lyman α survey with bar{n} = 60 deg^{-2} will allow Ων to be measured at a 2.26 per cent level. This corresponds to an idealized measurement of ∑mν at the precision of (100 ± 2.26)meV and fν = Ων/Ωm at 2.49 per cent level.

  12. Exposure to fenvalerate causes brain impairment during zebrafish development.

    PubMed

    Gu, Aihua; Shi, Xiangguo; Yuan, Chen; Ji, Guixiang; Zhou, Yong; Long, Yan; Song, Ling; Wang, Shoulin; Wang, Xinru

    2010-09-01

    Compared with increasing evidence suggesting that fenvalerate is neurotoxic to adults, further information regarding developmental toxicity of this compound attracts more attention. In this study, we used zebrafish as an environmental monitoring model to further explore the potential toxicity of fenvalerate. Our results demonstrated that larvae exposed to fenvalerate for 24-96 h displayed obvious morphological abnormalities, and the LC50 concentrations were 131.95 microg/L (LC50-24h), 107.18 microg/L (LC50-48 h), 21.76 microg/L (LC50-72 h), and 6.25 microg/L (LC50-96 h). To further investigate the effects of fenvalerate on embryos and larvae, acridine orange staining was performed at a 50 microg/L concentration. Staining showed notable signs of apoptosis mainly in the brain. Further studies revealed that fenvalerate induced alterations in SOD activity in larvae were concentration dependent and also related to the length of exposure. Fenvalerate also down-regulated the expression of ogg1 and dlx2 genes in a concentration dependent manner, which indicated that the oxidative-DNA repair system as well as neurogenesis were impaired. In this study, we investigated the toxicity of fenvalerate using zebrafish, that provided new evidence of observable brain impairment during embryogenesis due to fenvalerate exposure and discussed their implications for the development of fenvalerate induced neurotoxicity.

  13. Crystal structures of two (±)-exo-N-isobornyl­acetamides

    PubMed Central

    Stepanovs, Dmitrijs; Posevins, Daniels; Turks, Maris

    2015-01-01

    The title compounds consist of a bornane skeleton with attached acetamide, C12H21NO (±)-(1) {systematic name: (±)-N-[(1RS,2RS,4RS)-1,7,7-tri­methylbi­cyclo­[2.2.1]heptan-2-yl]acetamide}, and chloro­acetamide, C12H20ClNO (±)-(2) {systematic name: (±)-2-chloro-N-[(1RS,2RS,4RS)-1,7,7-tri­methylbi­cyclo­[2.2.1]heptan-2-yl]­acetamide}, functionalities to the 2-exo-position. The crystal structure of the first monoclinic polymorph of (±)-(1) has been reported previously [Ung et al. (2014 ▸). Monatsh. Chem. 145, 983–992]. Compound (±)-(1) crystallizes in the space group P21/n with two independent mol­ecules in the asymmetric unit, in contrast to the above-mentioned polymorph which crystallized in the space group C2/c with one mol­ecule in the asymmetric unit. In the title compounds, the bicyclic bornane moieties have normal geometries. In the crystals of both compounds, mol­ecules are linked by N—H⋯O hydrogen bonds, reinforced by C—H⋯O contacts, forming trans-amide chains propagating along the a-axis direction. In the case of compound (±)-(1), neighbouring chains are linked by further C—H⋯O contacts, forming double-chain ribbons along [100]. PMID:26594386

  14. THE IDENTIFICATION OF THE X-RAY COUNTERPART TO PSR J2021+4026

    SciTech Connect

    Weisskopf, Martin C.; Elsner, Ronald F.; O'Dell, Stephen L.; Tennant, Allyn F.; Romani, Roger W.; Razzano, Massimiliano; Belfiore, Andrea; Saz Parkinson, Pablo; Ziegler, Marcus; Dormody, Michael; Ray, Paul S.; Kerr, Matthew; Harding, Alice; Swartz, Douglas A.; Carraminana, Alberto; Becker, Werner; Kanbach, Gottfried; De Luca, Andrea; Thompson, David J.

    2011-12-10

    We report the probable identification of the X-ray counterpart to the {gamma}-ray pulsar PSR J2021+4026 using imaging with the Chandra X-ray Observatory Advanced CCD Imaging Spectrometer and timing analysis with the Fermi satellite. Given the statistical and systematic errors, the positions determined by both satellites are coincident. The X-ray source position is R.A. 20{sup h}21{sup m}30.{sup s}733, decl. +40 Degree-Sign 26'46.''04 (J2000) with an estimated uncertainty of 1.''3 combined statistical and systematic error. Moreover, both the X-ray to {gamma}-ray and the X-ray to optical flux ratios are sensible assuming a neutron star origin for the X-ray flux. The X-ray source has no cataloged infrared-to-visible counterpart and, through new observations, we set upper limits to its optical emission of i' > 23.0 mag and r' > 25.2 mag. The source exhibits an X-ray spectrum with most likely both a power law and a thermal component. We also report on the X-ray and visible light properties of the 43 other sources detected in our Chandra observation.

  15. Investigation of Mixed Surfactant Films at Water Surface Using Molecular Dynamics Simulations.

    PubMed

    Habartová, Alena; Roeselová, Martina; Cwiklik, Lukasz

    2015-10-27

    Multicomponent Langmuir monolayers are important models of organic coatings of naturally occurring water-vapor interfaces such as the surfaces of oceans or aerosol particles. We investigated mixed monolayers comprised of palmitic acid, C15H31COOH (PA) and 1-bromoalkanes of different chain length (C5, C10, and C16) at the air-water interface employing classical molecular dynamics simulations. Different composition ratios and lateral compression of the monolayers were considered. The structural parameters, such as density profiles, and deuterium order parameter, evaluated as functions of composition and the lateral film packing, provide microscopic information about organization and dynamics of the mixed monolayers. Simulations demonstrate that stable and well mixed monolayers are formed by the mixtures of PA and BrC16H33 (BrCl6), whereas the two considered shorter bromoalkanes, BrC5H11 (BrC5) and BrC10H21 (BrC10), do not form stable films. This is in accord with earlier experimental studies. Under high lateral pressures, in PA/BrC10 mixed systems molecules of the bromoalkane readily flip in the monolayer and subsequently leave the film, while the molecules of the longer BrC16 are expelled from the PA film but no flipping occurs. These results suggest that the film collapse under pressure is preceded by squeezing-out of bromoalkanes from the PA monolayer. PMID:26439598

  16. Crystal structure of [bis-(2-amino-ethyl-κN)(2-{[4-(tri-fluoro-meth-yl)benzyl-idene]amino}-eth-yl)amine-κN]di-chlorido-copper(II).

    PubMed

    Bussey, Katherine A; Cavalier, Annie R; Mraz, Margaret E; Holderread, Ashley S; Oshin, Kayode D; Oliver, Allen G; Zeller, Matthias

    2016-01-01

    The Cu(II) atom in the title compound, [CuCl2(C14H21F3N4)], adopts a coordination geometry that is between distorted square-based pyramidal and very Jahn-Teller-elongated octa-hedral. It is coordinated by three N atoms from the bis-(2-amino-eth-yl)(2-{[4-(tri-fluoro-meth-yl)benzyl-idene]amino}-eth-yl)amine and two chloride ligands. The two crystallographically unique copper complexes present in the asymmetric unit exhibit noticeable differences in the coordination bond lengths. Considering the Cu(II) atoms as having square-pyramidal geometry, the basal Cu-Cl bond lengths are typical [2.2701 (12) and 2.2777 (12) Å], while the apical distances are considerably elongated [2.8505 (12) and 2.9415 (12) Å]. For each mol-ecule, a Cu(II) atom from inversion-related mol-ecules are in nearby proximity to the remaining axial Cu(II) sites, but the Cu⋯Cl distances are very long [3.4056 (12) and 3.1645 (12) Å], attributable to van der Waals contacts. Nonetheless, these contacts appear to have some structure-directing properties, leading to association into dimers. These dimers associate via stacking of the aromatic rings to form extended zigzag chains. PMID:26870592

  17. Intrapulmonary pharmacokinetics of azithromycin in healthy volunteers given five oral doses.

    PubMed Central

    Olsen, K M; San Pedro, G; Gann, L P; Gubbins, P O; Halinski, D M; Campbell, G D

    1996-01-01

    The intrapulmonary pharmacokinetics of oral azithromycin were studied in 25 healthy volunteers, each of whom received an initial dose of 500 mg and then 250 mg once daily for four additional doses. Bronchoscopy, bronchoalveolar lavage, and venipuncture were performed 4, 28, 76, 124, 172, 244, 340, and 508 h after the first dose was administered. Azithromycin concentrations in epithelial lining fluid (ELF), alveolar macrophages, peripheral blood monocytes, and serum were measured by high-performance liquid chromatography. Azithromycin was extensively concentrated in cells and ELF. Drug concentrations in AMs (peak mean +/- standard deviation, 464 +/- 65 micrograms/ml) exceeded 80 micrograms/ml up to 508 h (21 days) following the first dose, while concentrations in PBMs (peak, 124 +/- 28 micrograms/ml) exceeded 20 micrograms/ml up to 340 h (14 days). Azithromycin concentrations in ELF peaked at 124 h (3.12 +/- 0.93 micrograms/ml) and were detectable up to 172 h (7 days), when they were 20 times the concurrent serum concentrations. Although the clinical significance of antibiotic concentrations in these compartments is nuclear, the sustained lung tissue penetration and extensive phagocytic accumulation demonstrated in this study support the proven efficacy of azithromycin administered on a 5-day dosage schedule in the treatment of extracellular or intracellular pulmonary infections. PMID:8913469

  18. 4-(4-{[(2-Phenyl­quinazolin-4-yl)­oxy]methyl}-1H-1,2,3-triazol-1-yl)butan-1-ol hemihydrate

    PubMed Central

    Ouahrouch, Abdelaaziz; Lazrek, Hassan B.; Taourirte, Moha; El Azhari, Mohamed; Saadi, Mohamed; El Ammari, Lahcen

    2011-01-01

    The title compound, C21H21N5O2·0.5H2O, has two fused six-membered rings linked to a benzene ring and to a triazole ring, which is connected to a butanol group. The quinazoline ring forms a dihedral angle of 7.88 (8)° with the benzene ring, while the triazole ring is approximately perpendicular to the benzene ring and to the quinazoline system, making dihedral angles of 84.38 (10) and 76.55 (8)°, respectively. The stereochemical arrangement of the butanol chain, with a C—C—C—C torsion angle of 178.34 (19)°, corresponds to an anti­periplanar conformation. However the position of the –OH group is split into two very close [O—O = 0.810(3) Å] positions of equal occupancy. The crystal structure features O—H⋯N and O—H⋯O hydrogen bonds, building an infinite three-dimensional network. The water molecule is located on a half-filled general position. PMID:22091058

  19. Synthesis, crystal structure, interaction with BSA and antibacterial activity of La(III) and Sm(III) complexes with enrofloxacin.

    PubMed

    Wang, Yan-Jun; Hu, Rui-Ding; Jiang, Dong-Hua; Zhang, Ping-Hua; Lin, Qiu-Yue; Wang, Yun-Yun

    2011-03-01

    Two new La(III) and Sm(III) complexes with enrofloxacin (HER, 1-cyclopropyl-7-(4-ethyl-1-piperazinyl)-6-fluoro-1,4-dihydro-4-oxo-3-quinoline carboxylic acid, C(19)H(21)FN(3)O(3)), [La(2)(ER)(6)(H(2)O)(2)]·14H(2)O(1) and [Sm(2)(ER)(6)(H(2)O)(2)]·14H(2)O(2) have been synthesized and characterized by elemental analysis, FT-IR, TG-DTG and X-ray single crystal diffraction. Both of the complexes are triclinic system with space group Pī. The structure of the complexes show that each rare earth atom in both complexes was nine-coordinated. Two of the enrofloxacin ions acted as tridentate chelate and bridging ligands, while the others as bidentate chelate ligands. The binding reaction between the complexes and bovine serum albumin (BSA) was studied by UV-vis absorption spectra and fluorescence spectroscopy. The results indicated that the two complexes had a quite strong ability to quench the fluorescence from BSA and the binding reaction was mainly a static quenching process. The binding constants K ( A )/(L·mol(-1)) were 1.46 × 10(5)(1) and 8.59 × 10(6)(2) and one binding site was formed. The synchronous spectroscopy suggested that tryptophan residues were placed in BSA. It was also found that the two complexes exhibited greater antimicrobial activity than enrofloxacin at given concentrations.

  20. Volatilization of arsenic from polluted soil by Pseudomonas putida engineered for expression of the arsM Arsenic(III) S-adenosine methyltransferase gene.

    PubMed

    Chen, Jian; Sun, Guo-Xin; Wang, Xiao-Xue; Lorenzo, Víctor de; Rosen, Barry P; Zhu, Yong-Guan

    2014-09-01

    Even though arsenic is one of the most widespread environmental carcinogens, methods of remediation are still limited. In this report we demonstrate that a strain of Pseudomonas putida KT2440 endowed with chromosomal expression of the arsM gene encoding the As(III) S-adenosylmethionine (SAM) methyltransfase from Rhodopseudomonas palustris to remove arsenic from contaminated soil. We genetically engineered the P. putida KT2440 with stable expression of an arsM-gfp fusion gene (GE P. putida), which was inserted into the bacterial chromosome. GE P. putida showed high arsenic methylation and volatilization activity. When exposed to 25 μM arsenite or arsenate overnight, most inorganic arsenic was methylated to the less toxic methylated arsenicals methylarsenate (MAs(V)), dimethylarsenate (DMAs(V)) and trimethylarsine oxide (TMAs(V)O). Of total added arsenic, the species were about 62 ± 2.2% DMAs(V), 25 ± 1.4% MAs(V) and 10 ± 1.2% TMAs(V)O. Volatilized arsenicals were trapped, and the predominant species were dimethylarsine (Me2AsH) (21 ± 1.0%) and trimethylarsine (TMAs(III)) (10 ± 1.2%). At later times, more DMAs(V) and volatile species were produced. Volatilization of Me2AsH and TMAs(III) from contaminated soil is thus possible with this genetically engineered bacterium and could be instrumental as an agent for reducing the inorganic arsenic content of soil and agricultural products. PMID:25122054

  1. Alkyl monolayer passivated metal-semiconductor diodes: 2: Comparison with native silicon oxide.

    PubMed

    Liu, Yong-Jun; Yu, Hua-Zhong

    2003-04-14

    To understand the electrical properties at passivated metal-semiconductor interfaces, two types of mercury-insulator-silicon (n-type) junctions, Hg\\C10H21-Si and Hg\\SiO2-Si, were fabricated and their current-voltage and capacitance-voltage characteristics compared. Both of them exhibited near-ideal rectifying characteristics with an excellent saturation current at reverse bias, which is in contrast to the previously reported ohmic behavior of an unmodified mercury-silicon junction. The experimental results also indicated that the n-decyl monolayer passivated junction possesses a higher effective barrier height, a lower ideality factor (that is, closer to unity), and better reproducibility than that of native silicon oxide. In addition, the dopant density and build-in potential, extracted from capacitance-voltage measurements of these passivated mercury-silicon junctions, revealed that alkyl monolayer derivatization does not alter the intrinsic properties of the silicon substrate. The calculated surface state density at the alkyl monolayer\\silicon interface is lower than that of the silicon oxide\\silicon interface. The present study increases the possibility of using advanced organic materials as ultrathin insulator layers for miniaturized, silicon-based microelectronic devices.

  2. Biophysical studies on the interactions of a classic mitochondrial uncoupler with bovine serum albumin by spectroscopic, isothermal titration calorimetric and molecular modeling methods.

    PubMed

    Zhang, Yue; Li, Jia-Han; Ge, Yu-Shu; Liu, Xiao-Rong; Jiang, Feng-Lei; Liu, Yi

    2011-03-01

    The interaction between a classic uncoupler (2,4-dinitrophenol, DNP) and bovine serum albumin (BSA) was investigated by fluorescence spectroscopy under the physiological conditions. The fluorescence quenching constants were calculated by the Stern-Volmer equation, and based upon the temperature dependence of quenching constants, it was proved that DNP caused a static quenching of the intrinsic fluorescence of BSA. Owing to the static quenching mechanism, different associative binding constants at various temperatures were determined and thus the thermodynamic parameters, namely enthalpy (ΔH=-21.12 kJ mol(-1)) and entropy changes (ΔS=23.51 J mol(-1) K(-1)) could be calculated based on the binding constants. Moreover, the enthalpy and entropy changes are consistent with the "Enthalpy-Entropy Compensation" equation obtained from our previous work. The negative enthalpy and positive entropy indicated that the electrostatic interactions played a major role in DNP-BSA binding process. Site marker competitive displacement experiments were carried out by using fluorescence and isothermal titration calorimetry (ITC) methods. These results showed that DNP bound with high affinity to Sudlow's site I (subdomain IIA) of BSA. The distance (r=3.78 nm) between donor (BSA) and acceptor (DNP) was obtained according to the mechanism of fluorescence resonance energy transfer (FRET). Furthermore, the results of synchronous fluorescence and circular dichroism (CD) spectroscopic studies indicated that the microenvironment and the secondary conformation of BSA were altered. The above results were supported by theoretical molecular modeling methods.

  3. Bohr effect of human hemoglobin A: magnitude of negative contributions determined by the equilibrium between two tertiary structures.

    PubMed

    Okonjo, Kehinde O; Olatunde, Abimbola M; Fodeke, Adedayo A; Babalola, J Oyebamiji

    2014-06-01

    We have measured the affinity of the CysF9[93]β sulfhydryl group of human deoxyhemoglobin and oxyhemoglobin for 5,5'-dithiobis(2-nitrobenzoate), DTNB, between pH ≈5.6 and 9 in order to understand the basis of the reported reduction of the Bohr effect induced by chemical modification of the sulfhydryl. We analyzed the results quantitatively on the basis of published data indicating that the sulfhydryl exists in two conformations that are coupled to the transition between two tertiary structures of hemoglobin in dynamic equilibrium. Our analyses show that the ionizable groups linked to the DTNB reaction have lower pKas of ionization in deoxyhemoglobin compared to oxyhemoglobin. So these ionizable groups should make negative contributions to the Bohr effect. We identify these groups as HisNA2[2]β, HisEF1[77]β and HisH21[143]β. We provide explanations for the finding that hemoglobin, chemically modified at CysF9[93]β, has a lower Bohr effect and a higher oxygen affinity than unmodified hemoglobin.

  4. Macondo oil in deep-sea sediments: Part 1 - sub-sea weathering of oil deposited on the seafloor.

    PubMed

    Stout, Scott A; Payne, James R

    2016-10-15

    Chemical analysis of sediment cores collected up to 8km from the Macondo well in 2010/2011 demonstrates the extent of weathering of the Macondo oil deposited in deep-sea sediments following the Deepwater Horizon disaster. On average, dissolution and biodegradation of the oil on the seafloor increased with distance from the well indicating that weathering occurred rapidly and overwhelmingly during the oil's transport as dispersed oil droplets within the deep-sea plume. Beyond about 5km from the well, the oil deposited on the seafloor had lost most mass below C25, was relatively enriched in n-C25+ n-alkanes and C3- and C4-alkylated benz[a]anthracenes/chrysenes, the latter owing to 95% depletion of total PAHs. Biodegradation of C28 and C29 tricyclic terpanes, C34 and C35 17α(H),21β(H)-homohopanes, C27 13β(H),17α(H)-dia and C27 14β(H),17β(H)-steranes and dissolution of C26 to C28 triaromatic steroids occurred. The results provide a means to distinguish Macondo oil in deep-sea sediments from naturally-occurring seep oils and pervasive ambient background hydrocarbons.

  5. Methyl (2Z)-2-(2-fluoro-4-meth­oxy­benzyl­idene)-5-(4-meth­oxy­phen­yl)-7-methyl-3-oxo-2,3-dihydro-5H-[1,3]thia­zolo[3,2-a]pyrimidine-6-carboxyl­ate

    PubMed Central

    Fun, Hoong-Kun; Loh, Wan-Sin; Sarojini, B. K.; Umesha, K.; Narayana, B.

    2011-01-01

    The asymmetric unit of the title compound, C24H21FN2O5S, consists of two crystallographically independent mol­ecules. In each mol­ecule, the central dihydro­pyrimidine ring is significantly puckered and adopts a conformation which is best described as an inter­mediate between a boat and a screw boat. The least-squares planes of the dihydro­pyrimidine rings are almost coplanar with the fluoro-substituted benzene rings, making dihedral angles of 9.04 (7) and 6.68 (7)°, and almost perpendicular to the meth­oxy-substituted benzene rings with dihedral angles of 89.23 (7) and 88.30 (7)°. In the mol­ecular structure, S(6) ring motifs are formed by C—H⋯O and C—H⋯S hydrogen bonds. In the crystal, mol­ecules are linked into a three-dimensional network by inter­molecular C—H⋯O and C—H⋯F hydrogen bonds. The crystal structure is further stabilized by a C—H⋯π inter­action. PMID:22090962

  6. Crystal structures of two (±)-exo-N-isobornyl-acetamides.

    PubMed

    Stepanovs, Dmitrijs; Posevins, Daniels; Turks, Maris

    2015-10-01

    The title compounds consist of a bornane skeleton with attached acetamide, C12H21NO (±)-(1) {systematic name: (±)-N-[(1RS,2RS,4RS)-1,7,7-tri-methylbi-cyclo-[2.2.1]heptan-2-yl]acetamide}, and chloro-acetamide, C12H20ClNO (±)-(2) {systematic name: (±)-2-chloro-N-[(1RS,2RS,4RS)-1,7,7-tri-methylbi-cyclo-[2.2.1]heptan-2-yl]-acetamide}, functionalities to the 2-exo-position. The crystal structure of the first monoclinic polymorph of (±)-(1) has been reported previously [Ung et al. (2014 ▸). Monatsh. Chem. 145, 983-992]. Compound (±)-(1) crystallizes in the space group P21/n with two independent mol-ecules in the asymmetric unit, in contrast to the above-mentioned polymorph which crystallized in the space group C2/c with one mol-ecule in the asymmetric unit. In the title compounds, the bicyclic bornane moieties have normal geometries. In the crystals of both compounds, mol-ecules are linked by N-H⋯O hydrogen bonds, reinforced by C-H⋯O contacts, forming trans-amide chains propagating along the a-axis direction. In the case of compound (±)-(1), neighbouring chains are linked by further C-H⋯O contacts, forming double-chain ribbons along [100].

  7. Identification of a novel HIP1-ALK fusion variant in Non-Small-Cell Lung Cancer (NSCLC) and discovery of ALK I1171 (I1171N/S) mutations in two ALK-rearranged NSCLC patients with resistance to Alectinib.

    PubMed

    Ou, Sai-Hong Ignatius; Klempner, Samuel J; Greenbowe, Joel R; Azada, Michele; Schrock, Alexa B; Ali, Siraj M; Ross, Jeffrey S; Stephens, Philip J; Miller, Vincent A

    2014-12-01

    Huntingtin-interacting protein 1 (HIP1) has recently been identified as a new fusion partner fused to anaplastic lymphoma kinase (ALK) in non-small-cell lung cancer (NSCLC). To date, two variants of HIP1-ALK (H21; A20) and (H28; A20) have been identified in NSCLC. However, the response of patients with NSCLC harboring HIP1-ALK to ALK inhibitors and potential resistance mechanisms to such remain unknown. Here, we report a patient with NSCLC harboring a novel HIP1-ALK fusion variant (H30; A20). This patient and another patient with EML4-ALK variant 3a/b initially responded sequentially to crizotinib and then alectinib, a next-generation ALK inhibitor, but developed acquired resistance to alectinib with the presence of a mutation in amino acid residue 1171 (I1171N and I1171S respectively) located in the hydrophobic regulatory spine (R-spine) of the ALK kinase in both the cases as identified by a comprehensive next-generation sequencing-based assay performed on biopsies of new liver metastases that developed during alectinib treatment.

  8. Rapid identification and differentiation of non-O157 Shiga toxin-producing Escherichia coli using polymerase chain reaction coupled to electrospray ionization mass spectrometry.

    PubMed

    Shen, Jinling; Wang, Fei; Li, Feng; Housley, Roberta; Carolan, Heather; Yasuda, Irene; Burrows, Erik; Binet, Rachel; Sampath, Rangarajan; Zhang, Jianmin; Allard, Marc W; Meng, Jianghong

    2013-08-01

    A polymerase chain reaction (PCR)-mass spectroscopy assay was developed to identify non-O157 Shiga toxin-producing Escherichia coli (STEC) with Plex-ID biosensor system, a platform identifying short PCR amplicons by specific base compositions. This assay simultaneously amplifies five fragments of two housekeeping genes, two subunits of stx2 gene, and four other virulence genes of STEC. A total of 164 well-characterized STEC isolates were examined with the assay to build a DNA base composition database. Another panel of 108 diverse STEC isolates was tested with the established database to evaluate the assay's identification capability. Among the 108 isolates, the assay specificity was 100% for three (stx1, eae, and aggA) out of five tested virulence genes, but 99% for stx2 and 96% for hlyA, respectively. Main stx1/stx2 subtypes and multiple alleles of stx1/stx2 could be differentiated. The assay successfully identified several clinically significant serotypes, including O91:H14, O103:H25, O145:H28/NM, O113:H21, and O104:H4. Meanwhile, it was able to group isolates with different levels of pathogenic potential. The results suggest that this high-throughput method may be useful in clinical and regulatory laboratories for STEC identification, particularly strains with increased pathogenic potential.

  9. [Survival of VTEC O157 and non-O157 in water troughs and bovine feces].

    PubMed

    Polifroni, Rosana; Etcheverría, Analía I; Arroyo, Guillermo H; Padola, Nora L

    2014-01-01

    Verotoxin-producing Escherichia coli (VTEC) is the etiologic agent of hemolytic-uremic syndrome (HUS), which typically affects children ranging in age from six months to five years old. Transmission is produced by consumption of contaminated food, by direct contact with animals or the environment and from person to person. In previous studies we determined that the environment of a dairy farm is a non-animal reservoir; thus, we proposed to study the survival of 4 VTEC isolates (O20:H19; O91:H21; O157:H7 and O178:H19) in sterile water troughs and bovine feces by viable bacteria count and detection of virulence genes by PCR. It was demonstrated that the survival of different VTEC isolates (O157 and non-O157) varied in terms of their own characteristics as well as of the environmental conditions where they were found. The main differences between isolates were their survival time and the maximal counts reached. The competitive and adaptive characteristics of some isolates increase the infection risk for people that are visiting or working on a farm, as well as the risk for reinfection of the animals and food contamination.

  10. Hydrocarbon geochemistry of the Puget Sound region - II. Sedimentary diterpenoid, steroid and triterpenoid hydrocarbons

    NASA Astrophysics Data System (ADS)

    Barrick, Robert C.; Hedges, John I.

    1981-03-01

    Cyclic components of the 'aliphatic' hydrocarbon mixtures extracted from Puget Sound sediment cores include a suite of C 19 and C 20 diterpenoid hydrocarbons of which fichtelite. sandaracopimaradiene, and isopimaradiene have been identified. Although apparently also derived from vascular plants, these diterpenoid hydrocarbons have relative abundances distinctly different from the co-existing plant wax n-alkane suite. Five C 27, C 28 and C 29 diasteranes and four C 29, C 30 and C 31 17α(H), 21β(H) hopanes occur in relatively constant proportion as components of a highly weathered fossil hydrocarbon assemblage. These chromatographically resolved cycloalkanes. along with the strongly covarying unresolved complex mixture, have been introduced to Puget Sound sediments from adjacent urban centres at increasing levels over the last 100 yr in the absence of any major oil spill. Naturally-occurring triterpenoid hydrocarbons, including hop-22(29)-ene (diploptene), are also present. A new group of C 30 polyenes has been detected which contains compounds apparently structurally related to a co-existing bicyclic C 25 diene and to C 20 and C 25 acyclic multibranched hydrocarbons described in a previous paper ( BARRICK et al., 1980).

  11. N-arylated-lactam-type iminosugars as new immunosuppressive agents: discovery, optimization, and biological evaluation.

    PubMed

    Wu, Xiaowei; Zhang, Fu-Yu; Zhu, Jingjing; Song, Chengcheng; Xiong, De-Cai; Zhou, Yifa; Cui, Yuxin; Ye, Xin-Shan

    2014-08-01

    We have previously described the discovery of N-alkylated iminosugars that showed immunosuppressive activity both in vitro and in vivo. Herein, we report the synthesis and biological evaluation of N-arylated lactam-type iminosugar derivatives. The synthesis started from simple monosaccharides and featured a Buchwald-Hartwig coupling reaction to construct the key N-aryl connection, thereby providing a highly diverse compound library. Structure-activity relationship studies, guided by a mouse-spleen-proliferation assay, led to the identification of 'hit' compound 12 f. Subsequently, the systematic modification of compound 12 f afforded compounds 21 h, 21 k, 21 n, 21 t, and 21 x with improved activities (IC50 =12-30 μM) and low Jurkat cytotoxicities (IC50 >100 μM). These new compounds also inhibited the secretion of IFN-γ and IL-4, which are hallmark cytokines of Th1 and Th2 cells, respectively. This work demonstrated that the N-arylated iminosugar structure represents a new scaffold with immunosuppressive activity.

  12. Methyl trans-(±)-1-oxo-2-phenethyl-3-(thio­phen-2-yl)-1,2,3,4-tetra­hydro­isoquinoline-4-carboxyl­ate

    PubMed Central

    Akkurt, Mehmet; Karaca, Selvi; Bogdanov, Milen G.; Kandinska, Meglena I.; Büyükgüngör, Orhan

    2009-01-01

    In the title compound, C23H21NO3S, the piperidine ring of the tetra­hydro­isoquinolinone unit adopts a screw-boat conformation. The thio­phene ring is disordered in a 0.700 (3):0.300 (3) ratio by an approximate 180° rotation of the ring around the C—C bond linking the ring to the tetra­hydro­isoquinolinone unit. The benzene ring of the tetra­hydro­isoquinolinone unit makes dihedral angles of 83.1 (2) and 62.38 (11)° with the major occupancy thio­phene ring and the phenyl ring, respectively. The dihedral angle between the phenyl ring and the thio­phene ring is 71.0 (2)°. In the crystal structure, mol­ecules are linked together by inter­molecular C—H⋯O and C—H⋯π inter­actions. PMID:21583149

  13. 4-[(3-Benzamido­methyl-6-phenyl-6,7-dihydro-5H-1,2,4-triazolo[3,4-b][1,3,4]thia­diazin-7-yl)carbon­yl]-3-phenyl-1,2,3-oxadiazol-3-ium-5-olate 0.06-hydrate

    PubMed Central

    Fun, Hoong-Kun; Hemamalini, Madhukar; Nithinchandra; Kalluraya, Balakrishna

    2011-01-01

    The asymmetric unit of the title compound, C27H21N7O4S·0.06H2O, contains four syndone mol­ecules and a water mol­ecule with a site occupancy of 0.25. In two of the syndone mol­ecules, three atoms in a terminal phenyl ring are disordered over two sets of sites, with occupancy ratios of 0.500 (18):0.500 (18) and 0.512 (17):0.488 (17). The dihedral angles between terminal phenyl rings for the syndone mol­ecules are 23.3 (4), 45.57 (16), 68.46 (16) and 56.5 (3)°. In the crystal, mol­ecules are connected via N—H⋯N, N—H⋯O, O—H⋯O, O—H⋯N and C—H⋯O hydrogen bonds, forming a three-dimensional network. PMID:21522639

  14. The adsorption and mass-transfer process of cationic red X-GRL dye on natural zeolite.

    PubMed

    Tian, Jingjing; Guan, Junfang; Gao, Huimin; Wen, Yafei; Ren, Zijie

    2016-01-01

    The adsorption behavior of natural zeolite was studied in order to determine the adsorption capacity and mass-transfer process of cationic red X-GRL (C(18)H(21)BrN(6)) onto the adsorbent. The adsorption tests to determine both the uptake capacity and the mass-transfer process at equilibrium were performed under batch conditions, which showed rapid uptake in general for the initial 5 min, corresponding to 92% total removal. The equilibrium adsorption capacity value (q(e,cal)) in pseudo-second-order kinetics was 13.51 mg/g at 293 K and the whole adsorption process was governed by physical adsorption with an endothermic, endothermic spontaneous nature. Adsorption tests indicated that the zeolite has great potential as an alternative low-cost material in the treatment of X-GRL drainage. However, the mass-transfer process to determine the rate-controlling steps showed that both film diffusion and pore diffusion were important in controlling the adsorption rate. The adsorption process was governed by film diffusion while pore diffusion was poor because the X-GRL molecules could not penetrate into the zeolite easily. The X-GRL molecules were only adsorbed on the external surface of the zeolite. Hence, to improve the adsorption capacity of natural zeolite further, modification to expand its micropores is necessary.

  15. Diploptene: an indicator of terrigenous organic carbon in Washington coastal sediments

    NASA Technical Reports Server (NTRS)

    Prahl, F. G.; Hayes, J. M.

    1992-01-01

    The pentacyclic triterpene 17 beta(H),21 beta(H)-hop-22(29)-ene (diploptene) occurs in sediments throughout the Columbia River drainage basin and off the southern coast of Washington state in concentrations comparable to long-chain plantwax n-alkanes. The same relationship is evident for diploptene and long-chain n-alkanes in soils from the Willamette Valley. Microorganisms indigenous to soils and soil erosion are indicated as the biological source and physical process, respectively, for diploptene in coastal sediments. Similarity between the stable carbon isotopic composition (delta 13CPDB) of diploptene isolated from soil in the Willamette Valley (-31.2 +/- 0.3%) and from sediments deposited throughout the Washington coastal environment (-31.2 +/- 0.5%) supports this argument. Values of delta for diploptene in river sediments are variable and 8-17% lighter, indicating that an additional biological source such as methane-oxidizing bacteria makes a significant contribution to the diploptene record in river sediments. Selective biodegradation resulting from a difference in the physicochemical association within eroded particles can explain the absence of the more-13C-depleted form of diploptene in Washington coastal sediments, but this mechanism remains unproven.

  16. Diploptene: An indicator of terrigenous organic carbon in Washington coastal sediments

    SciTech Connect

    Not Available

    1992-09-01

    The pentacyclic triterpene 17[beta](H),21[beta](H)-hop-22(29)-ene (diploptene) occurs in sediments throughout the Columbia River drainage basin and off the southern coast of Washington state in concentrations comparable to long-chain plantwax n-alkanes. The same relationship is evident for diploptene and long-chain n-alkanes in soils from the Willamette Valley. Microorganisms indigenous to soils and soil erosion are indicated as the biological source and physical process, respectively, for diploptene in coastal sediments. Similarity between the stable carbon isotopic composition ([delta][sup 13]C[sub PDB]) of diploptene isolated from soil in the Willamette Valley (-31.2+/-0.3%) and from sediments deposited throughout the Washington coastal environment (-31.2+/-0.5%) supports this argument. Values of 6 for diploptene in river sediments are variable and 8-17[per thousand] lighter, indicating that an additional biological source such as methane-oxidizing bacteria makes a significant contribution to the diploptene record in river sediments. Selective biodegradation resulting from a difference in the physicochemical association within eroded particles can explain the absence of the more-[sup 13]C-depleted form of diploptene in Washington coastal sediments, but this mechanism remains unproven. 28 refs., 5 figs., 2 tabs.

  17. Virulence profiles of Shiga Toxin-Producing Escherichia coli and other potentially diarrheagenic E.coli of bovine origin, in Mendoza, Argentina

    PubMed Central

    Pizarro, M.A.; Orozco, J.H.; Degarbo, S.M.; Calderón, A.E.; Nardello, A.L.; Laciar, A.; Rüttler, M.E.

    2013-01-01

    This study described a group of strains obtained from a slaughter house in Mendoza, in terms of their pathogenic factors, serotype, antibiotype and molecular profile. Ninety one rectal swabs and one hundred eight plating samples taken from carcasses of healthy cattle intended for meat consumption were analyzed. Both the swab and the plate samples were processed to analyze the samples for the presence of virulence genes by PCR: stx1, stx2, eae and astA. The Stx positive strains were confirmed by citotoxicity assay in Vero cells. The isolates were subsequently investigated for their O:H serotype, antimicrobial susceptibility and molecular profile by Random Amplification of Polymorphic DNA (RAPD). Twelve E.coli strains were identified by their pathogenicity. Nine were from fecal origin and three from carcasses. Three strains carried the stx1 gene, three the stx2 gene, two carried eae and four the astA gene. The detected serotypes were: O172:H-; O150:H8; O91:H21; O178:H19 and O2:H5. The strains showed a similarity around 70% by RAPD. Some of the E.coli strains belonged to serogroups known for certain life-threatening diseases in humans. Their presence in carcasses indicates the high probability of bacterial spread during slaughter and processing. PMID:24688508

  18. Macondo oil in deep-sea sediments: Part 1 - sub-sea weathering of oil deposited on the seafloor.

    PubMed

    Stout, Scott A; Payne, James R

    2016-10-15

    Chemical analysis of sediment cores collected up to 8km from the Macondo well in 2010/2011 demonstrates the extent of weathering of the Macondo oil deposited in deep-sea sediments following the Deepwater Horizon disaster. On average, dissolution and biodegradation of the oil on the seafloor increased with distance from the well indicating that weathering occurred rapidly and overwhelmingly during the oil's transport as dispersed oil droplets within the deep-sea plume. Beyond about 5km from the well, the oil deposited on the seafloor had lost most mass below C25, was relatively enriched in n-C25+ n-alkanes and C3- and C4-alkylated benz[a]anthracenes/chrysenes, the latter owing to 95% depletion of total PAHs. Biodegradation of C28 and C29 tricyclic terpanes, C34 and C35 17α(H),21β(H)-homohopanes, C27 13β(H),17α(H)-dia and C27 14β(H),17β(H)-steranes and dissolution of C26 to C28 triaromatic steroids occurred. The results provide a means to distinguish Macondo oil in deep-sea sediments from naturally-occurring seep oils and pervasive ambient background hydrocarbons. PMID:27488960

  19. Molecular structure, spectroscopic and quantum chemical studies of 1‧,3‧,3‧-trimethylspiro[benzo[f]chromene-3,2‧-indoline

    NASA Astrophysics Data System (ADS)

    Asiri, Abdullah M.; Ersanlı, Cem Cüneyt; Şahin, Onur; Arshad, Muhammad Nadeem; Hameed, Salem A.

    2016-05-01

    In this work, synthesis, X-ray single crystal determination, nuclear magnetic resonance (1H NMR and 13C NMR), Ultraviolet-Visible (UV-vis), Fourier transform infrared spectroscopy (FT-IR) and quantum mechanical studies of the 1‧,3‧,3‧-trimethylspiro[benzo[f]chromene-3,2‧-indoline [(C23H21NO), TMSBCI] have been both experimentally and theoretically reported. The molecular structure obtained from X-ray single-crystal analysis of the investigated compound in the ground state has been compared using Hartree-Fock (HF) and density functional theory (DFT) with the functional B3LYP using the 6-31G(d,p) as basis set. In addition to the optimized geometrical structures, atomic charges, molecular electrostatic potential (MEP) and natural bond orbital (NBO) have been investigated by using B3LYP/6-31G(d,p) level of the theoretical approximation for the title compound. The energetic behavior of TMSBCI has been examined in solvent media using polarizable continuum model (PCM). The total dipole moment (μ), the average linear polarizability (α), and the first-order hyperpolarisability (β) values of the investigated molecule have been computed using the same method. The experimental measurements (1H NMR, 13C NMR and UV-vis) have been compared with its corresponding the calculated values (using DFT). Besides, frontier molecular orbitals (FMOs) and thermodynamic properties have also been studied.

  20. Crystal structure of (4-meth-oxy-phen-yl)[(4-meth-oxy-phen-yl)phospho-nato]dioxidophosphate(1-) 2-amino-6-benzyl-3-eth-oxy-carbon-yl-4,5,6,7-tetra-hydro-thieno[2,3-c]pyridin-6-ium.

    PubMed

    Mague, Joel T; Mohamed, Shaaban K; Akkurt, Mehmet; Younes, Sabry H H; Ahmed, Essam K; Albayati, Mustafa R

    2015-12-01

    The asymmetric unit of the title mol-ecular salt, C17H21N2O2S(+)·C14H15O7P2 (-), comprises two cations and two anions. Each cation features an intra-molecular N-H⋯O hydrogen bond, which closes an S(6) ring; in each case the hydro-pyridine ring adopts a half-chair conformation. In the anions, the dihedral angles between the aromatic rings are 64.1 (2) and 54.9 (2)°. In each case, the diphosphate groups are close to eclipsed [C-P⋯P-C pseudo-torsion angles = 11.6 (2) and -19.3 (2)°]. One of the meth-oxy groups in each anion is disordered over two orientations in a 0.539 (18):0.461 (18) ratio in one anion and 0.82 (2):0.18 (2) in the other. In the crystal, O-H⋯O and N-H⋯O hydrogen bonds link the components into [100] chains. Numerous C-H⋯O inter-actions cross-link the chains into a three-dimensional network. PMID:26870570

  1. Crystal structure of (4-meth­oxy­phen­yl)[(4-meth­oxy­phen­yl)phospho­nato]dioxidophosphate(1−) 2-amino-6-benzyl-3-eth­oxy­carbon­yl-4,5,6,7-tetra­hydro­thieno[2,3-c]pyridin-6-ium

    PubMed Central

    Mague, Joel T.; Mohamed, Shaaban K.; Akkurt, Mehmet; Younes, Sabry H. H.; Ahmed, Essam K.; Albayati, Mustafa R.

    2015-01-01

    The asymmetric unit of the title mol­ecular salt, C17H21N2O2S+·C14H15O7P2 −, comprises two cations and two anions. Each cation features an intra­molecular N—H⋯O hydrogen bond, which closes an S(6) ring; in each case the hydro­pyridine ring adopts a half-chair conformation. In the anions, the dihedral angles between the aromatic rings are 64.1 (2) and 54.9 (2)°. In each case, the diphosphate groups are close to eclipsed [C—P⋯P—C pseudo-torsion angles = 11.6 (2) and −19.3 (2)°]. One of the meth­oxy groups in each anion is disordered over two orientations in a 0.539 (18):0.461 (18) ratio in one anion and 0.82 (2):0.18 (2) in the other. In the crystal, O—H⋯O and N—H⋯O hydrogen bonds link the components into [100] chains. Numerous C—H⋯O inter­actions cross-link the chains into a three-dimensional network. PMID:26870570

  2. Crystal structure of [bis­(2-amino­ethyl-κN)(2-{[4-(tri­fluoro­meth­yl)benzyl­idene]amino}­eth­yl)amine-κN]di­chlorido­copper(II)

    PubMed Central

    Bussey, Katherine A.; Cavalier, Annie R.; Mraz, Margaret E.; Holderread, Ashley S.; Oshin, Kayode D.; Oliver, Allen G.; Zeller, Matthias

    2016-01-01

    The CuII atom in the title compound, [CuCl2(C14H21F3N4)], adopts a coordination geometry that is between distorted square-based pyramidal and very Jahn–Teller-elongated octa­hedral. It is coordinated by three N atoms from the bis­(2-amino­eth­yl)(2-{[4-(tri­fluoro­meth­yl)benzyl­idene]amino}­eth­yl)amine and two chloride ligands. The two crystallographically unique copper complexes present in the asymmetric unit exhibit noticeable differences in the coordination bond lengths. Considering the CuII atoms as having square-pyramidal geometry, the basal Cu—Cl bond lengths are typical [2.2701 (12) and 2.2777 (12) Å], while the apical distances are considerably elongated [2.8505 (12) and 2.9415 (12) Å]. For each mol­ecule, a CuII atom from inversion-related mol­ecules are in nearby proximity to the remaining axial CuII sites, but the Cu⋯Cl distances are very long [3.4056 (12) and 3.1645 (12) Å], attributable to van der Waals contacts. Nonetheless, these contacts appear to have some structure-directing properties, leading to association into dimers. These dimers associate via stacking of the aromatic rings to form extended zigzag chains. PMID:26870592

  3. Shiga toxin-encoding genes (stx genes) in human faecal samples.

    PubMed

    Urdahl, Anne Margrete; Solheim, Heidi Tetlie; Vold, Line; Hasseltvedt, Viggo; Wasteson, Yngvild

    2013-03-01

    The aim of the two studies reported here was to investigate the distribution of stx genes in human faecal samples from volunteers and in faecal samples submitted to a regional microbiology hospital laboratory, and to isolate and characterize STEC from stx-positive samples. In total, faecal samples from 13.9% of 165 volunteers and 36.1% of 416 swabs from the regional microbiology hospital laboratory were positive for stx genes after screening by PCR. Isolation of STEC and of E. coli O157 from stx-positive faecal samples was performed by a filter-hybridization protocol and by automated immunomagnetic separation, respectively, and isolates were further characterized by serotyping, virulence typing by PCR and toxin production by the Vero cell assay. STEC were isolated from two samples only, an O146:H21 isolate from one of the volunteers and an O157:H7 isolate from a human case of diarrhoea. To conclude; the results show that it is not unusual to detect stx genes in faecal samples from humans in Norway, both from asymptomatic people and from people with gastrointestinal illness. This finding emphasizes the importance of correct diagnostic criteria for interpretation of the finding of an occasional stx-positive sample or an STEC isolate when searching for an aetiological agent of human cases of diarrhoea.

  4. 1-[(4-Chloro­phen­yl)(phen­yl)meth­yl]piperazine-1,4-diium bis­(trichloro­acetate)–trichloro­acetic acid (1/1)

    PubMed Central

    Song, Yanxi; Chidan Kumar, C. S.; Akkurt, Mehmet; Chandraju, S.; Li, Hongqi

    2012-01-01

    In the title salt adduct, C17H21ClN2 2+·2C2Cl3O2 −·C2HCl3O2, the Cl atom of the dication is disordered over two positions in a 0.915 (3):0.085 (3) ratio. The Cl atoms in the trichloroacetate anions and trichloroacetic acid molecule are also disordered, with refined site-occupation factors of 0.59 (3):0.41 (3), 0.503 (12):0.417 (12) and 0.653 (12):0.347 (12). The piperazine ring adopts a chair conformation, with puckering parameters Q T = 0.587 (3) Å, θ = 2.6 (2) and Φ 334 (6)°. In the crystal, neighbouring mol­ecules are linked by N—H⋯O, O—H⋯O, N—H⋯Cl, C—H⋯O and C—H⋯Cl hydrogen bonds, forming a three-dimensional network. PMID:22969587

  5. Mid Infrared Hydrogen Recombination Line Emission from the Maser Star MWC 349A

    NASA Technical Reports Server (NTRS)

    Smith, Howard A.; Strelnitski, V.; Miles, J. W.; Kelly, D. M.; Lacy, J. H.

    1997-01-01

    We have detected and spectrally resolved the mid-IR hydrogen recombination lines H6(alpha)(12.372 micrometers), H7(alpha)(19.062 micrometers), H7(beta)(l1.309 micrometers) and H8(gamma)(12.385 micrometers) from the star MWC349A. This object has strong hydrogen maser emission (reported in the millimeter and submillimeter hydrogen recombination lines from H36(alpha) to H21(alpha)) and laser emission (reported in the H15(alpha), H12(alpha) and H10(alpha) lines). The lasers/masers are thought to arise predominantly in a Keplerian disk around the star. The mid-IR lines do not show evident signs of lasing, and can be well modeled as arising from the strong stellar wind, with a component arising from a quasi-static atmosphere around the disk, similar to what is hypothesized for the near IR (less than or equal to 4 micrometers) recombination lines. Since populations inversions in the levels producing these mid-IR transitions are expected at densities up to approximately 10(exp 11)/cu cm, these results imply either that the disk does not contain high-density ionized gas over long enough path lengths to produce a gain approximately 1, and/or that any laser emission from such regions is small compared to the spontaneous background emission from the rest of the source as observed with a large beam. The results reinforce the interpretation of the far-IR lines as true lasers.

  6. Stability of dioctyl sulfosuccinate (DOSS) towards hydrolysis and photodegradation under simulated solar conditions.

    PubMed

    Batchu, Sudha Rani; Ramirez, Cesar E; Gardinali, Piero R

    2014-05-15

    Dioctyl sulfosuccinate (DOSS) is one of the main components of Corexit® EC9500A, a chemical dispersant formulation used at the surface and at depth during the response to the Deepwater Horizon incident. Despite being a high volume use chemical, data on its environmental stability are scarce. Hydrolysis and photodegradation of DOSS in both pure water and seawater were reported in the present study. DOSS photodegraded much faster under ultraviolet light source (254 nm, with half-life in hours) compared to relevant environmental light sources i.e., 350 nm and solar simulator (with half-lives in days). LC/MS-MS analysis of hydrolysis and photo-irradiated samples showed the presence of a common degradation product. MS/MS fragmentation of that product indicated a substitution of an octyl group by a hydroxyl group with a corresponding formula of C12H21O7S, which was confirmed by HRMS detection (Q-TOF, m/z 309.1017, +1.29 ppm).

  7. Aggregation-induced emission enhancement in alkoxy-bridged binuclear rhenium(I) complexes: application as sensor for explosives and interaction with microheterogeneous media.

    PubMed

    Sathish, Veerasamy; Ramdass, Arumugam; Lu, Zong-Zhan; Velayudham, Murugesan; Thanasekaran, Pounraj; Lu, Kuang-Lieh; Rajagopal, Seenivasan

    2013-11-21

    The aggregation-induced emission enhancement (AIEE) characteristics of the two alkoxy-bridged binuclear Re(I) complexes [{Re(CO)3(1,4-NVP)}2(μ2-OR)2] (1, R = C4H9; 2, C10H21) bearing a long alkyl chain with 4-(1-naphthylvinyl)pyridine (1,4-NVP) ligand are illustrated. These complexes in CH2Cl2 (good solvent) are weakly luminescent, but their intensity increased enormously by almost 500 times by the addition of poor solvent (CH3CN) due to aggregation. By tracking this process via UV-vis absorption and emission spectral and TEM techniques, the enhanced emission is attributed to the formation of nanoaggregates. The nanoaggregate of complex 2 is used as a sensor for nitroaromatic compounds. Furthermore, the study of the photophysical properties of these binuclear Re(I) complexes in cationic, cetyltrimethylammonium bromide (CTAB), anionic, sodium dodecyl sulfate (SDS), and nonionic, p-tert-octylphenoxypolyoxyethanol (TritonX-100, TX-100), micelles as well as in CTAB-hexane-water and AOT-isooctane-water reverse micelles using steady-state and time-resolved spectroscopy and TEM analysis reveals that the nanoaggregates became small and compact size.

  8. Structural insights into HDAC6 tubulin deacetylation and its selective inhibition.

    PubMed

    Miyake, Yasuyuki; Keusch, Jeremy J; Wang, Longlong; Saito, Makoto; Hess, Daniel; Wang, Xiaoning; Melancon, Bruce J; Helquist, Paul; Gut, Heinz; Matthias, Patrick

    2016-09-01

    We report crystal structures of zebrafish histone deacetylase 6 (HDAC6) catalytic domains in tandem or as single domains in complex with the (R) and (S) enantiomers of trichostatin A (TSA) or with the HDAC6-specific inhibitor nexturastat A. The tandem domains formed, together with the inter-domain linker, an ellipsoid-shaped complex with pseudo-twofold symmetry. We identified important active site differences between both catalytic domains and revealed the binding mode of HDAC6 selective inhibitors. HDAC inhibition assays with (R)- and (S)-TSA showed that (R)-TSA was a broad-range inhibitor, whereas (S)-TSA had moderate selectivity for HDAC6. We identified a uniquely positioned α-helix and a flexible tryptophan residue in the loop joining α-helices H20 to H21 as critical for deacetylation of the physiologic substrate tubulin. Using single-molecule measurements and biochemical assays we demonstrated that HDAC6 catalytic domain 2 deacetylated α-tubulin lysine 40 in the lumen of microtubules, but that its preferred substrate was unpolymerized tubulin. PMID:27454931

  9. The adsorption and mass-transfer process of cationic red X-GRL dye on natural zeolite.

    PubMed

    Tian, Jingjing; Guan, Junfang; Gao, Huimin; Wen, Yafei; Ren, Zijie

    2016-01-01

    The adsorption behavior of natural zeolite was studied in order to determine the adsorption capacity and mass-transfer process of cationic red X-GRL (C(18)H(21)BrN(6)) onto the adsorbent. The adsorption tests to determine both the uptake capacity and the mass-transfer process at equilibrium were performed under batch conditions, which showed rapid uptake in general for the initial 5 min, corresponding to 92% total removal. The equilibrium adsorption capacity value (q(e,cal)) in pseudo-second-order kinetics was 13.51 mg/g at 293 K and the whole adsorption process was governed by physical adsorption with an endothermic, endothermic spontaneous nature. Adsorption tests indicated that the zeolite has great potential as an alternative low-cost material in the treatment of X-GRL drainage. However, the mass-transfer process to determine the rate-controlling steps showed that both film diffusion and pore diffusion were important in controlling the adsorption rate. The adsorption process was governed by film diffusion while pore diffusion was poor because the X-GRL molecules could not penetrate into the zeolite easily. The X-GRL molecules were only adsorbed on the external surface of the zeolite. Hence, to improve the adsorption capacity of natural zeolite further, modification to expand its micropores is necessary. PMID:27148713

  10. Biological marker distribution in coexisting kerogen, bitumen and asphaltenes in Monterey Formation diatomite, California

    NASA Technical Reports Server (NTRS)

    Tannenbaum, E.; Ruth, E.; Huizinga, B. J.; Kaplan, I. R.

    1986-01-01

    Organic-rich (18.2%) Monterey Formation diatomite from California was studied. The organic matter consist of 94% bitumen and 6% kerogen. Biological markers from the bitumen and from pyrolysates of the coexisting asphaltenes and kerogen were analyzed in order to elucidate the relationship between the various fractions of the organic matter. While 17 alpha(H), 18 alpha(H), 21 alpha(H)-28,30-bisnorhopane was present in the bitumen and in the pryolysate of the asphaltenes, it was not detected in the pyrolysates of the kerogen. A C40-isoprenoid with "head to head" linkage, however, was present in pyrolysates of both kerogen and asphaltenes, but not in the bitumen from the diatomite. The maturation level of the bitumen, based on the extent of isomerization of steranes and hopanes, was that of a mature oil, whereas the pyrolysate from the kerogen showed a considerably lower maturation level. These relationships indicate that the bitumen may not be indigenous to the diatomite and that it is a mature oil that migrated into the rock. We consider the possibility, however, that some of the 28,30-bisnorhopane-rich Monterey Formation oils have not been generated through thermal degradation of kerogen, but have been expelled from the source rock at an early stage of diagenesis.

  11. Volatilization of Arsenic from Polluted Soil by Pseudomonas putida Engineered for Expression of the arsM Arsenic(III) S-Adenosine Methyltransferase Gene

    PubMed Central

    2015-01-01

    Even though arsenic is one of the most widespread environmental carcinogens, methods of remediation are still limited. In this report we demonstrate that a strain of Pseudomonas putida KT2440 endowed with chromosomal expression of the arsM gene encoding the As(III) S-adenosylmethionine (SAM) methyltransfase from Rhodopseudomonas palustris to remove arsenic from contaminated soil. We genetically engineered the P. putida KT2440 with stable expression of an arsM-gfp fusion gene (GE P. putida), which was inserted into the bacterial chromosome. GE P. putida showed high arsenic methylation and volatilization activity. When exposed to 25 μM arsenite or arsenate overnight, most inorganic arsenic was methylated to the less toxic methylated arsenicals methylarsenate (MAs(V)), dimethylarsenate (DMAs(V)) and trimethylarsine oxide (TMAs(V)O). Of total added arsenic, the species were about 62 ± 2.2% DMAs(V), 25 ± 1.4% MAs(V) and 10 ± 1.2% TMAs(V)O. Volatilized arsenicals were trapped, and the predominant species were dimethylarsine (Me2AsH) (21 ± 1.0%) and trimethylarsine (TMAs(III)) (10 ± 1.2%). At later times, more DMAs(V) and volatile species were produced. Volatilization of Me2AsH and TMAs(III) from contaminated soil is thus possible with this genetically engineered bacterium and could be instrumental as an agent for reducing the inorganic arsenic content of soil and agricultural products. PMID:25122054

  12. Integrated Ultraviolet Spectra and Line Indices of M31 Globular Clusters and the Cores of Elliptical Galaxies

    NASA Astrophysics Data System (ADS)

    Ponder, Jerry M.; Burstein, David; O'Connell, Robert W.; Rose, James A.; Frogel, Jay A.; Wu, Chi-Chao; Crenshaw, D. Michael; Rieke, Marcia J.; Tripicco, Michael

    1998-11-01

    We present observations of the integrated light of four M31 globular clusters (MIV, MII, K280, and K58) and of the cores of six elliptical galaxies (NGC 3605, 3608, 5018, 5831, 6127, and 7619) made with the Faint Object Spectrograph on the Hubble Space Telescope. The spectra cover the range 2200-4800 Å at a resolution of 8 Å with signal-to-noise ratio of more than 20 and flux accuracy of ~5%. To these data we add from the literature IUE observations of the dwarf elliptical galaxy M32, Galactic globular clusters, and Galactic stars. The stellar populations in these systems are analyzed with the aid of mid-UV and near-UV colors and absorption line strengths. Included in the measured indices is the key NH feature at 3360 Å. We compare these line index measures with the 2600 - 3000 colors of these stars and stellar populations. We find that the M31 globular clusters, Galactic globular clusters/Galactic stars, and elliptical galaxies represent three distinct stellar populations, based on their behavior in color-line strength correlations involving Mg II, NH, CN, and several UV metallic blends. In particular, the M31 globular cluster MIV, as metal-poor as the Galactic globular M92, shows a strong NH 3360 Å feature. Other line indices, including the 3096 Å blend that is dominated by lines of Mg I and Al I, show intrinsic differences as well. We also find that the broadband line indices often employed to measure stellar population differences in faint objects, such as the 4000 Å and the Mg 2800 breaks, are disappointingly insensitive to these stellar population differences. We find that the hot (T > 20,000 K) stellar component responsible for the ``UV upturn'' at shorter wavelengths can have an important influence on the mid-UV spectral range (2400-3200 Å) as well. The hot component can contribute over 50% of the flux at 2600 Å in some cases and affects both continuum colors and line strengths. Mid-UV spectra of galaxies must be corrected for this effect before

  13. Tamarugite in the Steam-Condensate Alteration Paragenesis in Diana Cave (SW Romania)

    NASA Astrophysics Data System (ADS)

    Puscas, C. M.; Onac, B. P.; Effenberger, H. S.; Povară, I.

    2012-12-01

    The double-salt hydrate tamarugite [NaAl(SO4)2 6H2O] is an uncommon mineral in the cave environment, forming as a result of chemical reactions between water and bedrock only under very specific conditions. The Diana Cave hosts a unique tamarugite occurrence, the first one to be reported from a typical karst environment. The cave is located within the limits of Băile Herculane township in the Cerna Mountains, SW Romania. It consists of a 14 m long, westward-oriented single passage, developed along the Diana Fault. In 1974 a concrete-clad mine gallery was created to channel the thermal water (Diana 1+2 Spring) flowing through the cave to a pumping station. The spring's chemical and physical parameters fluctuated through time, averaging 51.98° C, discharge of 0.96 Ls-1, pH of 7.46, 5768.66 ppm TDS, 9303 μScm-1 conductivity, 5.02 salinity. The major chemical components of the thermo-mineral water in Diana Cave are, Na+ (1392.57 ppm), K+ (58.55 ppm), Ca2+ (725.16 ppm), Mg2+ (10.78 ppm), Cl- (3376.83 ppm), and SO42- (92.27 ppm), and H2S (24.05 ppm), with traces of Si, Fe2+, Br+, I-, and Li+. The general air circulation pattern within the cave is fairly simple: cold air from the outside sweeps into the cave along the floor, heats up at the contact with the thermo-mineral water, ascends, and exists the cave along the ceiling. At the contact with the cold walls of the Diana Cave, the hot steam condenses and gives rise to a rich and exotic sulfate-mineral paragenesis (including halotrichite-series minerals, gypsum, bassanite, anhydrite, epsomite, alunite, halite, native sulfur, etc.). The most exotic minerals precipitate at or below the contact between the Tithonic - Neocomian limestone and the overlaying Cretaceous shaly limestone, as a result of steam-condensate alteration. Minerogenetic mechanisms responsible for the peculiar sulfate mineral assemblage in Diana Cave are evaporation, oxidation, hydrolysis, double exchange reactions, and deposition from vapours or

  14. Assessment of extreme quantitative precipitation forecasts and development of regional extreme event thresholds using data from HMT-2006 and COOP observers

    USGS Publications Warehouse

    Ralph, F.M.; Sukovich, E.; Reynolds, D.; Dettinger, M.; Weagle, S.; Clark, W.; Neiman, P.J.

    2010-01-01

    Extreme precipitation events, and the quantitative precipitation forecasts (QPFs) associated with them, are examined. The study uses data from the Hydrometeorology Testbed (HMT), which conducted its first field study in California during the 2005/06 cool season. National Weather Service River Forecast Center (NWS RFC) gridded QPFs for 24-h periods at 24-h (day 1), 48-h (day 2), and 72-h (day 3) forecast lead times plus 24-h quantitative precipitation estimates (QPEs) fromsites in California (CA) and Oregon-Washington (OR-WA) are used. During the 172-day period studied, some sites received more than 254 cm (100 in.) of precipitation. The winter season produced many extreme precipitation events, including 90 instances when a site received more than 7.6 cm (3.0 in.) of precipitation in 24 h (i.e., an "event") and 17 events that exceeded 12.7 cm (24 h)-1 [5.0 in. (24 h)-1]. For the 90 extreme events f.7.6 cm (24 h)-1 [3.0 in. (24 h)-1]g, almost 90% of all the 270 QPFs (days 1-3) were biased low, increasingly so with greater lead time. Of the 17 observed events exceeding 12.7 cm (24 h)-1 [5.0 in. (24 h)-1], only 1 of those events was predicted to be that extreme. Almost all of the extreme events correlated with the presence of atmospheric river conditions. Total seasonal QPF biases for all events fi.e., $0.025 cm (24 h)-1 [0.01 in. (24 h)-1]g were sensitive to local geography and were generally biased low in the California-Nevada River Forecast Center (CNRFC) region and high in the Northwest River Forecast Center(NWRFC) domain. The low bias in CA QPFs improved with shorter forecast lead time and worsened for extreme events. Differences were also noted between the CNRFC and NWRFC in terms of QPF and the frequency of extreme events. A key finding from this study is that there were more precipitation events .7.6 cm (24 h)-1 [3.0 in. (24 h)21] in CA than in OR-WA. Examination of 422 Cooperative Observer Program (COOP) sites in the NWRFC domain and 400 in the CNRFC domain

  15. Crystallographic investigations of select cathinones: emerging illicit street drugs known as `bath salts'.

    PubMed

    Wood, Matthew R; Lalancette, Roger A; Bernal, Ivan

    2015-01-01

    The name `bath salts', for an emerging class of synthetic cathinones, is derived from an attempt to evade prosecution and law enforcement. These are truly illicit drugs that have psychoactive CNS (central nervous system) stimulant effects and they have seen a rise in abuse as recreational drugs in the last few years since first having been seen in Japan in 2006. The ease of synthesis and modification of specific functional groups of the parent cathinone make these drugs particularly difficult to regulate. MDPV (3,4-methylenedioxypyrovalerone) is commonly encountered as its hydrochloride salt (C16H21NO3·HCl), in either the hydrated or the anhydrous forms. This `bath salt' has various names in the US, e.g. `Super Coke', `Cloud Nine', and `Ivory Wave', to name just a few. We report here the structures of two forms of the HCl salt, one as a mixed bromide/chloride salt, C16H22NO3(+)·0.343Br(-)·0.657Cl(-) [systematic name: 1-(benzo[d][1,3]dioxol-5-yl)-2-(pyrrolidin-1-ium-1-yl)pentan-1-one bromide/chloride (0.343/0.657)], and the other with the H7O3(+) cation, as well as the HCl counter-ion [systematic name: hydroxonium 1-(benzo[d][1,3]dioxol-5-yl)-2-(pyrrolidin-1-ium-1-yl)pentan-1-one dichloride, H7O3(+)·C16H22NO3(+)·2Cl(-)]. This is one of a very few structures (11 to be exact) in which we have a new example of a precisely determined hydroxonium cation. During the course of researching the clandestine manufacture of MDPV, we were surprised by the fact that a common precursor of this illicit stimulant is known to be the fragrant species piperonal, which is present in the fragrances of orchids, most particularly in the case of the vanilla orchid. We found that MDPV can be made by a Grignard reaction of this heliotropin. This may also explain the unexpected appearance of the bromide counter-ion in some of the salts we encountered (C16H21NO3·HBr), one of which is presented here [systematic name: 1-(benzo[d][1,3]dioxol-5-yl)-2-(pyrrolidin-1-ium-1-yl)pentan-1-one

  16. Antimicrobial resistance of Shiga toxin (verotoxin)-producing Escherichia coli O157:H7 and non-O157 strains isolated from humans, cattle, sheep and food in Spain.

    PubMed

    Mora, Azucena; Blanco, Jesús E; Blanco, Miguel; Alonso, M Pilar; Dhabi, Ghizlane; Echeita, Aurora; González, Enrique A; Bernárdez, M Isabel; Blanco, Jorge

    2005-08-01

    A total of 722 Shiga toxin-producing Escherichia coli (STEC) isolates recovered from humans, cattle, ovines and food during the period from 1992 to 1999 in Spain were examined to determine antimicrobial resistance profiles and their association with serotypes, phage types and virulence genes. Fifty-eight (41%) out of 141 STEC O157:H7 strains and 240 (41%) out of 581 non-O157 STEC strains showed resistance to at least one of the 26 antimicrobial agents tested. STEC O157:H7 showed a higher percentage of resistant strains recovered from bovine (53%) and beef meat (57%) than from human (23%) and ovine (20%) sources, whereas the highest prevalence of antimicrobial resistance in non-O157 STEC was found among isolates recovered from beef meat (55%) and human patients (47%). Sulfisoxazole (36%) had the most common antimicrobial resistance, followed by tetracycline (32%), streptomycin (29%), ampicillin (10%), trimethoprim (8%), cotrimoxazole (8%), chloramphenicol (7%), kanamycin (7%), piperacillin (6%), and neomycin (5%). The multiple resistance pattern most often observed was that of streptomycin, sulfisoxazole, and tetracycline. Ten (7%) STEC O157:H7 and 71 (12%) non-O157 strains were resistant to five or more antimicrobial agents. Most strains showing resistance to five or more antimicrobial agents belonged to serotypes O4:H4 (4 strains), O8:H21 (3 strains), O20:H19 (6 strains), O26:H11 (8 strains eae-beta1), O111:H- (3 strains eae-gamma2), O118:H- (2 strains eae-beta1), O118:H16 (5 strains eae-beta1), O128:H- (2 strains), O145:H8 or O145:H- (2 strains eae-gamma1), O157:H7 (10 strains eae-gamma1), O171:H25 (3 strains), O177:H11 (5 strains eae-beta1), ONT:H- (3 strains/1 eae-beta1) and ONT:H21 (2 strains). Interestingly, most of these serotypes, i.e., those indicated in bold) were found among human STEC strains isolated from patients with hemolytic uremic-syndrome (HUS) reported in previous studies. We also detected, among non-O157 strains, an association between a higher

  17. Crystal structures, lattice potential energies, and thermochemical properties of crystalline compounds (1-C(n)H(2n+1)NH3)2ZnCl4(s) (n = 8, 10, 12, and 13).

    PubMed

    Liu, Yupu; Di, Youying; He, Donghua; Zhou, Qian; Dou, Jianmin

    2011-11-01

    As part of our ongoing project involving the study of (1-C(n)H(2n+1)NH(3))(2)MCl(4)(s) (where M is a divalent metal ion and n = 8-18), we have synthesized the compounds (1-C(n)H(2n+1)NH(3))(2)ZnCl(4)(s) (n = 8, 10, 12, and 13), and the details of the structures are reported herein. All of the compounds were crystallized in the monoclinic form with the space group P2(1)/n for (1-C(8)H(17)NH(3))(2)ZnCl(4)(s), P21/c for (1-C(10)H(21)NH(3))(2)ZnCl(4)(s), P2(1)/c for (1-C(12)H(25)NH(3))(2)ZnCl(4)(s), and P2(1)/m for (1-C(13)H(27)NH(3))(2)ZnCl(4)(s). The lattice potential energies and ionic volumes of the cations and the common anion of the title compounds were obtained from crystallographic data. Molar enthalpies of dissolution of the four compounds at various molalities were measured at 298.15 K in the double-distilled water. According to Pitzer's theory, molar enthalpies of dissolution of the title compounds at infinite dilution were obtained. Finally, using the values of molar enthalpies of dissolution at infinite dilution (Δ(s)H(m)(∞)) and other auxiliary thermodynamic data, the enthalpy change of the dissociation of [ZnCl(4)](2-)(g) for the reaction [ZnCl(4)](2-)(g)→ Zn(2+)(g) + 4Cl(-)(g) was obtained, and then the hydration enthalpies of cations were calculated by designing a thermochemical cycle.

  18. An Experimental Field Dataset with Buoyant, Neutral, and Dense Gas Atmospheric Releases and Model Comparisons in Low-Wind Speed (Diffusion) Conditions

    SciTech Connect

    Veronica E. Wannberg, Gustavious Williams, Patrick Sawyer, and Richard Venedam

    2010-09-01

    Aunique field dataset from a series of low–wind speed experiments, modeling efforts using three commonly used models to replicate these releases, and statistical analysis of how well these models were able to predict the plume concentrations is presented. The experiment was designed to generate a dataset to describe the behavior of gaseous plumes under low-wind conditions and the ability of current, commonly used models to predict these movements. The dataset documents the release and transport of three gases: ammonia (buoyant), ethylene (neutral), and propylene (dense) in low–wind speed (diffusion) conditions. Release rates ranged from 1 to 20 kg h21. Ammonia and ethylene had five 5-min releases each to represent puff releases and five 20-min releases each to represent plume releases. Propylene had five 5-min puffs, six 20-min plumes, and a single 30-min plume. Thirty-two separate releases ranging from 6 to 47 min were conducted, of which only 30 releases generated useful data. The data collected included release rates, atmospheric concentrations to 100 m from the release point, and local meteorological conditions. The diagnostics included nine meteorological stations on 100-m centers and 36 photoionization detectors in a radial pattern. Three current stateof- the-practice models, Aerial locations of Hazardous Atmospheres (ALOHA), Emergency Prediction Information code (EPIcode), and Second-Order Closure Integrated Puff (SCIPUFF), were used to try to duplicate the measured field results. Low wind speeds are difficult to model, and all of the models had difficulty replicating the field measurements. However, the work does show that these models, if used correctly, are conservative (overpredict concentrations) and can be used for safety and emergency planning.

  19. Genetic characterization of Shiga toxin-producing Escherichia coli (STEC) and atypical enteropathogenic Escherichia coli (EPEC) isolates from goat's milk and goat farm environment.

    PubMed

    Álvarez-Suárez, María-Elena; Otero, Andrés; García-López, María-Luisa; Dahbi, Ghizlane; Blanco, Miguel; Mora, Azucena; Blanco, Jorge; Santos, Jesús A

    2016-11-01

    The aim of this study was to characterize a collection of 44 Shiga toxin-producing (STEC) and enteropathogenic Escherichia coli (EPEC) isolated from goat milk and goat farm environment. Of the 19 STEC isolates, five (26.3%) carried the stx1 gene, four (21.1%) the stx2 gene and 10 (52.6%) presented both stx genes. Six (31.6%) STEC strains were eae-positive and belonged to serotypes related to severe human disease (O157:H7 and O5:HNM). Another seven STEC strains were of serotype O146:H21 and three of serotype O166:H28, also linked to human disease. The STEC strains isolated from goat milk were of serotypes potentially pathogenic for humans. All the 25 EPEC isolates were considered atypical (aEPEC) and one aEPEC strain was of serotype O26:H11, a serotype frequently isolated in children with diarrhea. Multilocus sequence typing (MLST) was carried out with seven housekeeping genes and 23 sequence types (ST) were detected, 14 of them newly described. Twelve STs grouped STEC isolates and 11 STs grouped EPEC isolates. Genetic typing by pulsed field gel electrophoresis (PFGE) resulted in 38 patterns which grouped in 10 clusters. Well-defined groups were also observed for strains of pathogenic serotypes. In conclusion, strains of STEC and aEPEC belonging to serotypes related to severe human disease have been detected in goat milk and the goat farm environment. Ruminants are an important reservoir of STEC strains and the role of these animals as carriers of other pathogenic types of E. coli seems to be an emerging concern.

  20. A longitudinal study of Vero cytotoxin producing Escherichia coli in cattle calves in Sri Lanka.

    PubMed Central

    Tokhi, A. M.; Peiris, J. S.; Scotland, S. M.; Willshaw, G. A.; Smith, H. R.; Cheasty, T.

    1993-01-01

    Two cohorts of 10 and 16 calves were followed at weekly or fortnightly intervals from 4-28 and 1-9 weeks respectively to determine whether natural infection by Vero cytotoxin (VT) producing Escherichia coli (VTEC) occurred. Ninety-one of 171 (53%) faecal specimens were VTEC positive and 20-80% of animals at any given time excreted VTEC. Of 104 VTEC strains studied further, 6 different serogroups (O 22.H16; O 25.H5; O 49.H-; O 86.H26; O 88.H25; O 153.H12) and an untypable strain (O? .H21) were identified. All strains belonging to the same serotype had identical profiles of reactivity with DNA probes to toxins VT1 or 2, LTI or II and a probe (CVD419) derived from a plasmid carried by enterohaemorrhagic Escherichia coli O 157.H7. Four of these serotypes were found in the faecal flora of the calves, taken as a group, throughout the 4-month study period. Sixty percent of the strains hybridized with the probe for VT1, 4% with the probe for VT2, and 36% with both probes. Faecal VTEC were significantly associated with overt diarrhoeal illness in animals < 10 weeks of age, but no characteristic profile of markers (serotype or hybridization pattern) in E. coli isolates was associated with diarrhoea. A serological response to VT1 was detected in some animals, but faecal VT1 VTEC excretion persisted in spite of seroconversion. VT1 seroconversion was not associated with diarrhoea. A serological response to VT2 was not detected even in those animals excreting VT2 VTEC in the faeces. PMID:8472764

  1. Deposition and Biodegradation of Submerged Oil from the Deepwater Horizon

    NASA Astrophysics Data System (ADS)

    Bagby, S. C.; Fisher, G. B.; Reddy, C. M.; Valentine, D. L.

    2014-12-01

    The 2010 sinking of the Deepwater Horizon in the Gulf of Mexico caused the release of ~5 million barrels of oil to the deep ocean. Roughly half of this oil, ~2 million barrels, is believed to have been trapped ~1000-1300 m deep in the water column, in plumes comprising water-soluble hydrocarbons in the aqueous phase and water-insoluble oil particles in suspension. While the soluble fraction was subject to rapid biodegradation, the fate of the oil particles has remained unknown. Using 17α(H),21β(H)-hopane (hopane) as a conservative marker of water-insoluble crude oil, we have examined the sediment data collected in support of the Natural Resource Damage Assessment process and identified a 3200-km2 depositional footprint surrounding the Macondo well. Under conservative assumptions, we estimate that this footprint accounts for ~12% of the suspended liquid oil. Monte Carlo modeling of the distribution of surficial hopane concentrations provides an initial estimate of the size distribution and spatial density of deposited particles, and suggests that the local spatial heterogeneity of particle deposition is likely to be extremely high, such that low-density sediment sampling is unlikely to capture the true extent of deposition. Thus, the 'missing' oil may be hiding in plain sight. Finally, we examined the spatial and temporal concentration distribution of >100 hydrocarbon compounds in relation to hopane, finding that, while there is clear evidence for biodegradation of many compounds, biodegradative efficiency appears to be impeded by high concentrations of oil, perhaps reflecting the low surface area to volume ratio of large oil particles.

  2. Alpha 7-type nicotinic acetylcholine receptor and prodynorphin mRNA expression after administration of (-)-nicotine and U-50,488H in beta-amyloid peptide (25-35)-treated mice.

    PubMed

    Hiramatsu, M; Watanabe, M; Baba, S; Kojima, R; Nabeshima, T

    2004-10-01

    We previously reported that (-)-nicotine and kappa-opioid receptor agonists lessened impairment of learning and/or memory in several animal models. Furthermore, these drugs prevented neurodegenerative damage induced by ischemia or beta-amyloid peptide (25-35). In the present study, we tested whether (-)-nicotine and U-50,488H prevent delayed-memory impairment induced by beta-amyloid peptide (25-35), and changes of expression of alpha7-type nicotinic acetylcholine receptor mRNA and prodynorphin mRNA. Seven days after treatment with beta-amyloid peptide (25-35) (9 nmol/mouse, i.c.v.), memory impairment was observed in the Y-maze test. Memory impairment was prevented when (-)-nicotine (6.16 micromol/kg, s.c.) or U-50,488H (21 micromol/kg, s.c.) was administered 1 h before, but not 1 h after, beta-amyloid peptide (25-35) treatment. There was no change in prodynorphin mRNA or alpha7-type nicotinic acetylcholine receptor mRNA expression in the hippocampus 10 days after beta-amyloid peptide (25-35) treatment alone. Of interest, mRNA expression of not only prodynorphin, but also the alpha7-type nicotinic acetylcholine receptor, was significantly decreased when U-50,488H was administered 1 h before, but not 1 h after, treatment with beta-amyloid peptide (25-35). However, these changes were not observed after the administration of (-)-nicotine. These results suggest that activation of the kappa-opioid system, but not beta7-type nicotinic receptors has a neuroprotective effect on beta-amyloid peptide (25-35)-induced memory impairment, and may be involved in the long-lasting changes in the expression of these mRNAs.

  3. A plant-based oral vaccine to protect against systemic intoxication by Shiga toxin type 2

    PubMed Central

    Wen, Sharon X.; Teel, Louise D.; Judge, Nicole A.; O’Brien, Alison D.

    2006-01-01

    Hemolytic uremic syndrome, the leading cause of kidney failure in children, often follows infection with enterohemorrhagic Escherichia coli and is mediated by the Shiga type toxins, particularly type 2 (Stx2), produced by such strains. The challenge in protecting against this life-threatening syndrome is to stimulate an immune response at the site of infection while also protecting against Shiga intoxication at distal sites such as the kidney. As one approach to meeting this challenge, we sought to develop and characterize a prototypic orally delivered, plant-based vaccine against Stx2, an AB5 toxin. First, we genetically inactivated the Stx2 active A subunit gene and then optimized both subunit genes for expression in plants. The toxoid genes were then transformed into the Nicotiana tabacum (tobacco) cell line NT-1 by Agrobacterium tumefaciens-mediated transformation. Toxoid expression was detected in NT-1 cell extracts, and the assembly of the holotoxoid was confirmed. Finally, mice were immunized by feeding with the toxoid-expressing NT-1 cells or by parenteral immunization followed by oral vaccination (prime–boost strategy). The immunized mice produced Stx2-specific mucosal IgA and Stx2-neutralizing serum IgG. The protective efficacy of these responses was assessed by challenging the immunized mice with E. coli O91:H21 strain B2F1, an isolate that produces an activatable variant of Stx2 (Stx2d) and is lethal to mice. The oral immunization fully protected mice from the challenge. Results of this study demonstrated that a plant-based oral vaccine can confer protection against lethal systemic intoxication. PMID:16641102

  4. Phylogenetic Analysis of Enteroaggregative Escherichia coli (EAEC) Isolates from Japan Reveals Emergence of CTX-M-14-Producing EAEC O25:H4 Clones Related to Sequence Type 131.

    PubMed

    Imuta, Naoko; Ooka, Tadasuke; Seto, Kazuko; Kawahara, Ryuji; Koriyama, Toyoyasu; Kojyo, Tsuyoshi; Iguchi, Atsushi; Tokuda, Koichi; Kawamura, Hideki; Yoshiie, Kiyotaka; Ogura, Yoshitoshi; Hayashi, Tetsuya; Nishi, Junichiro

    2016-08-01

    Enteroaggregative Escherichia coli (EAEC) causes acute or persistent diarrhea. The aggR gene is widely used as a marker for typical EAEC. The heterogeneity of EAEC is well known; however, there are few reports on the phylogenetic relationships of EAEC. Recently, CTX-M extended-spectrum β-lactamase (ESBL)-producing EAEC strains have been reported worldwide. To characterize EAEC strains in Japan, we investigated the population structure of EAEC. A total of 167 aggR-positive strains isolated from stool specimens from diarrheal patients in Kagoshima (139 strains) and Osaka (28 strains), Japan, between 1992 and 2010 were examined for the prevalence of EAEC virulence markers, the blaCTX-M gene, and the capacity to form biofilms. Multilocus sequence typing was also conducted. EAEC strains were widely distributed across four major E. coli phylogroups. Strains of O111:H21/clonal group 40 (CG40) (30 strains), O126:H27/CG200 (13 strains), and O86a:H27/CG3570 (11 strains) in phylogroup B1 are the historical EAEC clones in Japan, and they exhibited strong biofilm formation. Twenty-nine strains of EAEC O25:H4/CG131 were identified in phylogroup B2, 79% of which produced CTX-M-14. This clone has emerged since 2003. The clone harbored plasmid-encoded EAEC virulence genes but not chromosomal virulence genes and had lower biofilm-forming capacity than historical EAEC strains. This clone most likely emerged from a pandemic uropathogenic O25:H4/sequence type 131 clone by acquiring an EAEC virulence plasmid from canonical EAEC. Surveillance of the horizontal transfer of both virulence and ESBL genes among E. coli strains is important for preventing a worldwide increase in antimicrobial drug resistance. PMID:27252465

  5. Population trends of binary near-Earth asteroids based on radar and lightcurves observations

    NASA Astrophysics Data System (ADS)

    Brozovic, Marina; Benner, Lance A. M.; Naidu, Shantanu P.; Taylor, Patrick A.; Busch, Michael W.; Margot, Jean-Luc; Nolan, Michael C.; Howell, Ellen S.; Springmann, Alessondra; Giorgini, Jon D.; Shepard, Michael K.; Magri, Christopher; Richardson, James E.; Rivera-Valentin, Edgard G.; Rodriguez-Ford, Linda A.; Zambrano Marin, Luisa Fernanda

    2016-10-01

    The Arecibo and Goldstone planetary radars are invaluable instruments for the discovery and characterization of binary and triple asteroids in the near-Earth asteroid (NEA) population. To date, 41 out of 56 known binaries and triples (~73% of the objects) have been discovered by radar and 49 of these multiple systems have been detected by radar. Their absolute magnitudes range from 12.4 for (1866) Sisyphus to 22.6 for 2015 TD144 and have a mean and rms dispersion of 18.1+-2.0. There is a pronounced decrease in the abundance of binaries for absolute magnitudes H>20. One of the smallest binaries, 1994 CJ1, with an absolute magnitude H=21.4, is also the most accessible binary for a spacecraft rendezvous. Among 365 NEAs with H<22 (corresponding to diameters larger than ~ 140 m) detected by radar since 1999, ~13% have at least one companion. Two triple systems are known, (15391) 2001 SN263 and (136617) 1994 CC, but this is probably an underestimate due to low signal to noise ratios (SNRs) for many of the binary radar detections. Taxonomic classes have been reported for 41 out of 56 currently known multiple systems and some trends are starting to emerge: at least 50% of multiple asteroid systems are S, Sq, Q, or Sk, and at least 20% are optically dark (C, B, P, or U). Thirteen V-class NEAs have been observed by radar and six of them are binaries. Curiously, a comparable number of E-class objects have been detected by radar, but none is known to be a binary.

  6. Protective effects of bifidobacteria on intestines in newborn rats with necrotizing enterocolitis and its regulation on TLR2 and TLR4.

    PubMed

    Zhou, W; Lv, H; Li, M X; Su, H; Huang, L G; Li, J; Yuan, W M

    2015-09-28

    We established a necrotizing enterocolitis (NEC) rat model and explored the role of bifidobacteria in the intestines of the rats and its regulation on intestinal Toll-like receptors (TLRs). Seventy-five newborn Sprague-Dawley rats were randomly divided into 5 groups (15 rats/group): group A, artificial feeding group (formula-fed); group B, NEC model (LPS + formula-fed); group C, bifidobacterium (LPS + formula-fed + bifidobacterium microcapsules, intragastric administration); group D, artificial feeding + bifidobacterium (formula-fed + bifidobacterium microcapsules gavage); group E, rat breast-feeding group (rat breast-feeding). After 3 days of feeding, rats were placed in incubators, fasted for 12 h, and killed by decapitation. The ileocecal proximal segment ileum was fixed and sliced; pathological examination was conducted, and TLR2, TLR4, and nuclear factor-kB p65 protein expression in the intestinal tissue was detected by immunohistochemistry. There was a statistically significant difference in pathological scores between groups C and B (H = 21.789, P = 0.000), and the former was lower than the latter. TLR2, TLR4, and nuclear factor-kB p65 expression in intestinal tissue was determined in groups A-E. There were statistically significant differences between groups C and B (P = 0.001; P = 0.000; P = 0.000). Bifidobacteria had a protective effect on the intestines of newborn rats with NEC, which showed reduced NEC and intestinal damage severity. This observation may be related to the reduced levels of TLR2, TLR4, and nuclear factor-kB P65 observed during the inflammatory response.

  7. Product distributions, rate constants, and mechanisms of LiH +H reactions

    NASA Astrophysics Data System (ADS)

    Defazio, Paolo; Petrongolo, Carlo; Gamallo, Pablo; González, Miguel

    2005-06-01

    We present a quantum-mechanical investigation of the LiH depletion reaction LiH +H→Li+H2 and of the H exchange reaction LiH +H'→LiH'+H. We report product distributions, rate constant, and mechanism of the former, and rate constant and mechanism of the latter reaction. We use the potential-energy surface by Dunne et al. [Chem. Phys. Lett. 336, 1 (2001)], the real-wave-packet method by Gray and Balint-Kurti [J. Chem. Phys. 108, 950 (1998)], and the J-shifting approximation. The H21 nuclear-spin statistics and progressions of vib-rotational states (v',j') rule both initial-state-resolved and thermal product distributions, which have saw-toothed shapes with odd j' preferred with respect to even j'. At high collision energies and temperatures, we obtain a regular 3-to-1 intensity alternation of rotational states. At low collision energies and temperatures, the degeneracy and density of many H2 levels can, however, give more irregular distributions. During the collision, the energy flows from the reactant translational mode to the product vibration and recoil ones. The rate constants of both reactions are not Arrhenius type because the reactions are barrier-less. The low-temperature, LiH depletion rate constant is larger than the H exchange one, whereas the contrary holds at high temperature. The real-time mechanisms show the nuclear rearrangements of the nonreactive channel and of the reactive ones, and point out that the LiH depletion is preferred over the H exchange at short times. This confirms the rate-constant results.

  8. Protection against Shiga-Toxigenic Escherichia coli by Non-Genetically Modified Organism Receptor Mimic Bacterial Ghosts.

    PubMed

    Paton, Adrienne W; Chen, Austen Y; Wang, Hui; McAllister, Lauren J; Höggerl, Florian; Mayr, Ulrike Beate; Shewell, Lucy K; Jennings, Michael P; Morona, Renato; Lubitz, Werner; Paton, James C

    2015-09-01

    Shiga-toxigenic Escherichia coli (STEC) causes severe gastrointestinal infections in humans that may lead to life-threatening systemic sequelae, such as the hemolytic uremic syndrome (HUS). Rapid diagnosis of STEC infection early in the course of disease opens a window of opportunity for therapeutic intervention, for example, by administration of agents that neutralize Shiga toxin (Stx) in the gut lumen. We previously developed a recombinant bacterium that expresses a mimic of the Stx receptor globotriaosyl ceramide (Gb3) on its surface through modification of the lipopolysaccharide (A. W. Paton, R. Morona, and J. C. Paton, Nat Med 6:265-270, 2000, http://dx.doi.org/10.1038/73111). This construct was highly efficacious in vivo, protecting mice from otherwise fatal STEC disease, but the fact that it is a genetically modified organism (GMO) has been a barrier to clinical development. In the present study, we have overcome this issue by development of Gb3 receptor mimic bacterial ghosts (BGs) that are not classified as GMOs. Gb3-BGs neutralized Stx1 and Stx2 in vitro with high efficiency, whereas alternative Gb3-expressing non-GMO subbacterial particles (minicells and outer membrane blebs) were ineffective. Gb3-BGs were highly efficacious in a murine model of STEC disease. All mice (10/10) treated with Gb3-BGs survived challenge with a highly virulent O113:H21 STEC strain and showed no pathological signs of renal injury. In contrast, 6/10 mice treated with control BGs succumbed to STEC challenge, and survivors exhibited significant weight loss, neutrophilia, and histopathological evidence of renal damage. Thus, Gb3-BGs offer a non-GMO approach to treatment of STEC infection in humans, particularly in an outbreak setting.

  9. A plant-based oral vaccine to protect against systemic intoxication by Shiga toxin type 2.

    PubMed

    Wen, Sharon X; Teel, Louise D; Judge, Nicole A; O'Brien, Alison D

    2006-05-01

    Hemolytic uremic syndrome, the leading cause of kidney failure in children, often follows infection with enterohemorrhagic Escherichia coli and is mediated by the Shiga type toxins, particularly type 2 (Stx2), produced by such strains. The challenge in protecting against this life-threatening syndrome is to stimulate an immune response at the site of infection while also protecting against Shiga intoxication at distal sites such as the kidney. As one approach to meeting this challenge, we sought to develop and characterize a prototypic orally delivered, plant-based vaccine against Stx2, an AB5 toxin. First, we genetically inactivated the Stx2 active A subunit gene and then optimized both subunit genes for expression in plants. The toxoid genes were then transformed into the Nicotiana tabacum (tobacco) cell line NT-1 by Agrobacterium tumefaciens-mediated transformation. Toxoid expression was detected in NT-1 cell extracts, and the assembly of the holotoxoid was confirmed. Finally, mice were immunized by feeding with the toxoid-expressing NT-1 cells or by parenteral immunization followed by oral vaccination (prime-boost strategy). The immunized mice produced Stx2-specific mucosal IgA and Stx2-neutralizing serum IgG. The protective efficacy of these responses was assessed by challenging the immunized mice with E. coli O91:H21 strain B2F1, an isolate that produces an activatable variant of Stx2 (Stx2d) and is lethal to mice. The oral immunization fully protected mice from the challenge. Results of this study demonstrated that a plant-based oral vaccine can confer protection against lethal systemic intoxication. PMID:16641102

  10. Crystal structures of (E)-3-(furan-2-yl)-2-phenyl-N-tosyl-acryl-amide and (E)-3-phenyl-2-(m-tol-yl)-N-tosyl-acryl-amide.

    PubMed

    Cheng, Dong; Meng, Xiangzhen; Sheng, Zeyuan; Wang, Shuangming; Duan, Yuanyuan; Li, Ziqian

    2016-06-01

    In the title N-tosyl-acryl-amide compounds, C20H17NO4S, (I), and C23H21NO3S, (II), the conformation about the C=C bond is E. The acryl-amide groups, [-NH-C(=O)-C=C-], are almost planar, with the N-C-C=C torsion angle being -170.18 (14)° in (I) and -168.01 (17)° in (II). In (I), the furan, phenyl and 4-methyl-benzene rings are inclined to the acryl-amide mean plane by 26.47 (11), 69.01 (8) and 82.49 (9)°, respectively. In (II), the phenyl, 3-methyl-benzene and 4-methyl-benzene rings are inclined to the acryl-amide mean plane by 11.61 (10), 78.44 (10) and 78.24 (10)°, respectively. There is an intra-molecular C-H⋯π inter-action present in compound (II). In the crystals of both compounds, mol-ecules are linked by pairs of N-H⋯O hydrogen bonds, forming inversion dimers with an R 2 (2)(8) ring motif. In (I), the dimers are reinforced by C-H⋯O hydrogen bonds and linked by C-H⋯π inter-actions, forming chains along [011]. In the crystal of (II), the dimers are linked via C-H⋯O hydrogen bonds, forming chains along [100]. The chains are further linked by C-H⋯π inter-actions, forming layers parallel to (010).

  11. An isotopic biogeochemical study of the Green River oil shale

    NASA Technical Reports Server (NTRS)

    Collister, J. W.; Summons, R. E.; Lichtfouse, E.; Hayes, J. M.

    1992-01-01

    Thirty-five different samples from three different sulfur cycles were examined in this stratigraphically oriented study of the Shell 22x-l well (U.S.G.S. C177 core) in the Piceance Basin, Colorado. Carbon isotopic compositions of constituents of Green River bitumens indicate mixing of three main components: products of primary photoautotrophs and their immediate consumers (delta approximately -30% vs PDB), products of methanotrophic bacteria (delta approximately -85%), and products of unknown bacteria (delta approximately -40%). For individual compounds synthesized by primary producers, delta-values ranged from -28 to -32%. 13C contents of individual primary products (beta-carotane, steranes, acyclic isoprenoids, tricyclic triterpenoids) were not closely correlated, suggesting diverse origins for these materials. 13C contents of numerous hopanoids were inversely related to sulfur abundance, indicating that they derived both from methanotrophs and from other bacteria, with abundances of methanotrophs depressed when sulfur was plentiful in the paleoenvironment. gamma-Cerane coeluted with 3 beta(CH3),17 alpha(H),21 beta(H)-hopane, but delta-values could be determined after deconvolution. gamma-Cerane (delta approximately -25%) probably derives from a eukaryotic heterotroph grazing on primary materials, the latter compound (delta approximately -90%) must derive from methanotrophic organisms. 13C contents of n-alkanes in bitumen differed markedly from those of paraffins generated pyrolytically. Isotopic and quantitative relationships suggest that alkanes released by pyrolysis derived from a resistant biopolymer of eukaryotic origin and that this was a dominant constituent of total organic carbon.

  12. Geochemical imprint of depositional conditions on organic matter in laminated-Bioturbated interbeds from fine-grained marine sequences

    USGS Publications Warehouse

    Pratt, L.M.; Claypool, G.E.; King, J.D.

    1986-01-01

    Laminated organic-rich shales are interbedded at a scale of centimeters to a few meters with bioturbated organic-poor mudstones or limestones in some fine-grained marine sequences. We have analyzed the organic matter in pairs of laminated/bioturbated interbeds from Cretaceous and Devonian rocks deposited in epicontinental and oceanic settings for the purpose of studying the influence of depositional and early diagenetic environment on the organic geochemical properties of marine shales. Results of these analyses indicate that for rocks that are still in a diagenetic stage of thermal alteration, the relative abundance of biomarker compounds and specific biomarker indices can be useful indicators of depositional and early diagenetic conditions. Pristane/phytane ratios are generally highest for laminated rocks from epicontinental basins and appear to reflect the input of isoprenoid precursors more than oxygenated versus anoxic depositional conditions. The thermally immature laminated rocks are characterized by relatively high contents of 17??(H), 21??(H)-hopanes, hopenes, sterenes and diasterenes, and by strong predominance of the 22R over 22S homohopane isomers. Thermally immature bioturbated samples are characterized by absence of the ??,??-hopanes, by low contents of both saturated and unsaturated polycyclic hydrocarbons, and by slight or no predominance of the 22R over 22S homohopane isomers. There are less obvious compositional differences between the saturated hydrocarbons in the laminated and bioturbated units from the thermally mature sequences. For both the thermally mature and immature laminated samples, the degree of isomerization at the 22C position for hopanes and at the 20C position for steranes is generally consistent with the degree of thermal maturity interpreted from other properties of the organic matter. The bioturbated samples, however, exhibit inconsistent and anomalously high degrees of isomerization for the homohopanes, resulting either from

  13. Novel chitosan-derived nanomaterials and their micelle-forming properties.

    PubMed

    Zhang, Can; Ding, Ya; Ping, Qineng; Yu, Liangli Lucy

    2006-11-01

    Six novel N-alkyl-N-dimethyl and N-alkyl-N-trimethyl chitosan derivatives were chemically synthesized and characterized using FT-IR, 1H NMR, 13C NMR, differential scanning calorimetry (DSC), and X-ray diffraction spectrometry (XRD). The alkyl groups included octyl (C8H17-), decanyl (C10H21-), and lauryl (C12H25-). These chitosan derivatives were also evaluated for their micelle-forming properties using dynamic light scattering (DLS) and transmission electron microscopy (TEM) techniques. All six chitosan derivatives were capable of forming polymeric micelles in water with an average particle diameter ranging from 36 to 218 nm. Both N-octyl-N-dimethyl and N-octyl-N-trimethyl chitosan derivatives formed nanomicelles under the experimental conditions, with an average particle diameter of 36.0 and 52.5, respectively. Both the length of alkyl group and the N-trimethylation degree of the chitosan derivatives altered the size of their polymeric micelles. To further understand the effect of N-alkyl substitution degree of chitosan derivatives on size of their micelles, additional five N-octyl-N-trimethyl chitosan derivatives with N-alkyl substitution degree ranging from 8 to 58% were prepared and their micelle sizes were determined. The results showed that the diameter of the nanomicelles was proportional to the degree of N-octyl substitution. These data suggest that novel N-alkyl-N-dimethyl and N-alkyl-N-trimethyl chitosan derivatives may form nanomicelles. Additional research is required to further investigate the potential value-added utilization of these chitosan derivatives in controlled release and targeted delivery of hydrophobic bioactive food factors.

  14. Protection against Shiga-Toxigenic Escherichia coli by Non-Genetically Modified Organism Receptor Mimic Bacterial Ghosts.

    PubMed

    Paton, Adrienne W; Chen, Austen Y; Wang, Hui; McAllister, Lauren J; Höggerl, Florian; Mayr, Ulrike Beate; Shewell, Lucy K; Jennings, Michael P; Morona, Renato; Lubitz, Werner; Paton, James C

    2015-09-01

    Shiga-toxigenic Escherichia coli (STEC) causes severe gastrointestinal infections in humans that may lead to life-threatening systemic sequelae, such as the hemolytic uremic syndrome (HUS). Rapid diagnosis of STEC infection early in the course of disease opens a window of opportunity for therapeutic intervention, for example, by administration of agents that neutralize Shiga toxin (Stx) in the gut lumen. We previously developed a recombinant bacterium that expresses a mimic of the Stx receptor globotriaosyl ceramide (Gb3) on its surface through modification of the lipopolysaccharide (A. W. Paton, R. Morona, and J. C. Paton, Nat Med 6:265-270, 2000, http://dx.doi.org/10.1038/73111). This construct was highly efficacious in vivo, protecting mice from otherwise fatal STEC disease, but the fact that it is a genetically modified organism (GMO) has been a barrier to clinical development. In the present study, we have overcome this issue by development of Gb3 receptor mimic bacterial ghosts (BGs) that are not classified as GMOs. Gb3-BGs neutralized Stx1 and Stx2 in vitro with high efficiency, whereas alternative Gb3-expressing non-GMO subbacterial particles (minicells and outer membrane blebs) were ineffective. Gb3-BGs were highly efficacious in a murine model of STEC disease. All mice (10/10) treated with Gb3-BGs survived challenge with a highly virulent O113:H21 STEC strain and showed no pathological signs of renal injury. In contrast, 6/10 mice treated with control BGs succumbed to STEC challenge, and survivors exhibited significant weight loss, neutrophilia, and histopathological evidence of renal damage. Thus, Gb3-BGs offer a non-GMO approach to treatment of STEC infection in humans, particularly in an outbreak setting. PMID:26099582

  15. Effects of peroxyacetyl nitrate alone and in combination with ozone in healthy young women

    SciTech Connect

    Horvath, S.M.; Bedi, J.F.; Drechsler-Parks, D.M.

    1986-03-01

    Metabolic and pulmonary functions were investigated in 10 nonsmoking, young adult women who were exposed for 2 h (21/sup 0/C WBGT) to four conditions: filtered air (FA), 0.27 ppm peroxyacetyl nitrate (PAN), 0.48 ppm ozone (O/sub 3/), and 0.48 ppm O/sub 3/ + 0.27 ppm PAN (PAN/O/sub 3/). The subjects alternated 15-min periods of rest and 20-min periods of bicycle ergometer exercise eliciting a V/sub E/ of 25 L. Functional residual capacity (FRC) was determined pre- and post-exposure. Forced vital capacity (FVC) was determined before and after exposure, as well as 5 min after each exercise period. Heart rate was monitored throughout the exposure, and metabolic functions were measured during the last 2 min of each exercise period. There were no changes in any variable consequent to FA or PAN exposure. During O/sub 3/ and PAN/O/sub 3/ exposures, a decrease in V/sub T/, a concomitant increase in f/sub R/, and no change in V/sub E/ occurred. Both O/sub 3/ and PAN/O/sub 3/ induced significant (p < 0.05) decrements in FVC, FEV/sub 1.0/, FEV/sub 2.0/, FEV/sub 3.0/, FEF25-75 %, IC, ERV, and TLC, but following PAN/O/sub 3/ exposure the decrements were 10 percent greater. The results suggest an interactive effect between PAN and O/sub 3/. A comparison of data from this study and a similar study on men exercising at equivalent V/sub E/ found no difference in the pulmonary responses to the pollutants between men and women.

  16. In-stream attenuation of neuro-active pharmaceuticals and their metabolites

    USGS Publications Warehouse

    Writer, Jeffrey; Antweiler, Ronald C.; Ferrar, Imma; Ryan, Joseph N.; Thurman, Michael

    2013-01-01

    In-stream attenuation was determined for 14 neuro-active pharmaceuticals and associated metabolites. Lagrangian sampling, which follows a parcel of water as it moves downstream, was used to link hydrological and chemical transformation processes. Wastewater loading of neuro-active compounds varied considerably over a span of several hours, and thus a sampling regime was used to verify that the Lagrangian parcel was being sampled and a mechanism was developed to correct measured concentrations if it was not. In-stream attenuation over the 5.4-km evaluated reach could be modeled as pseudo-first-order decay for 11 of the 14 evaluated neuro-active pharmaceutical compounds, illustrating the capacity of streams to reduce conveyance of neuro-active compounds downstream. Fluoxetine and N-desmethyl citalopram were the most rapidly attenuated compounds (t1/2 = 3.6 ± 0.3 h, 4.0 ± 0.2 h, respectively). Lamotrigine, 10,11,-dihydro-10,11,-dihydroxy-carbamazepine, and carbamazepine were the most persistent (t1/2 = 12 ± 2.0 h, 12 ± 2.6 h, 21 ± 4.5 h, respectively). Parent compounds (e.g., buproprion, carbamazepine, lamotrigine) generally were more persistent relative to their metabolites. Several compounds (citalopram, venlafaxine, O-desmethyl-venlafaxine) were not attenuated. It was postulated that the primary mechanism of removal for these compounds was interaction with bed sediments and stream biofilms, based on measured concentrations in stream biofilms and a column experiment using stream sediments.

  17. ¹H-MRS before and after resuscitation following selective cerebral ultra-profound hypothermic blood flow occlusion in monkeys.

    PubMed

    Niu, X-Q; Zhao, X-X; Li, B-C; Gao, Y-J; Xu, W; Fan, Y-D; Fu, G-P; Wang, K; Pu, J

    2015-01-01

    We investigated the effect of selective cerebral ultra-profound hypothermic blood flow occlusion on brain tissue and cell metabolism to ascertain the efficacy and safety of selective deep hypothermic technologies using proton magnetic resonance spectroscopy ((1)H-MRS). The bilateral carotid artery was blocked at room temperature for 10 min. Other neck vessels were then blocked through cold perfusion of the internal carotid artery and reflux of the ipsilateral jugular vein. Thus, selective cerebral extracorporeal circulation was established. Brain temperature was reduced to 15.1° ± 0.9°C. After 60 min, cerebral blood flow recovered naturally. Routine magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI), and (1)H-MRS examination of the bilateral frontal cortex and basal ganglia were performed prior to surgery and 4, 24, 72 h, 21 days after recovery. The formants and areas under the curve (AUC) of N-acetyl aspartate (NAA), choline (Cho), creatine/phosphocreatine (Cr/Cr2) were analyzed using 1H-MRS. The pre- and postoperative AUC of NAA and Cho at different time points were compared. Conventional MRI and DWI showed no abnormal signal changes in the brain parenchyma or right basal ganglia before and after surgery (P > 0.05). There was no significant difference in the ratio between NAA/(Cr+Cr2) and Cho/(Cr+Cr2) before and after surgery in the bilateral basal ganglia and frontoparietal regions of the cortex (P > 0.05). Quantitative (1)H-MRS showed that selective deep cerebral hypothermia significantly improved the brain's tolerance to ischemia and hypoxia. Our results could provide a better understanding of the efficacy and safety of selective deep hypothermia and blood flow occlusion. PMID:26505410

  18. Biological marker distribution and significance in oils and rocks of the Monterey Formation, California

    NASA Astrophysics Data System (ADS)

    Curiale, Joseph A.; Cameron, Douglas; Davis, Dean V.

    1985-01-01

    The biological marker distributions of several oils, core extracts and solid bitumens of the Monterey Formation of California have been studied. Sterane, terpane and monoaromatic steroid hydrocarbons were analyzed in samples from the San Joaquin, Los Angeles, Ventura and Santa Maria Basins. The sterane patterns of both oils and extracts are characterized by (a) low relative concentrations of diasteranes, (b) low 20S/20R-5α,14α,17α-ethylcholestane ratios, (c) relatively high concentrations of cholestane ( vs. methyl- and ethylcholestane) isomers. San Joaquin Basin samples contain significant amounts of the 5β isomer, which is generally absent in samples from other basins. The carbon number distribution of 5α,14α,17α,20R steranes is similar for all oils, regardless of API gravity, depth or basin location, and is suggestive of open marine depositional conditions for the source material involved. 17α(H),l8α(H),21β(H)-28,30-Bisnorhopane is present in almost all samples. Certain San Joaquin Basin oils and extracts contain (a) a series of 25-nor hopanes, including 25,28,30-trisnorhopane, (b) a distinctive monoaromatic steroid hydrocarbon distribution, (c) an aliphatic hydrocarbon fraction devoid of n-paraffins. Biological marker characteristics suggest that the Monterey oils examined originated early in the maturational sequence, from elastics-poor source material. API gravities of the Monterey Formation oils examined vary monotonically with (a) bisnorhopane/hopane ratios, (b) aromatized/regular sterane ratios and (c) the concentration of monoaromatized steranes relative to terpanes and regular steranes. These oil gravity correlations exist regardless of sample depth or basin location.

  19. Topological data analysis of Escherichia coli O157:H7 and non-O157 survival in soils.

    PubMed

    Ibekwe, Abasiofiok M; Ma, Jincai; Crowley, David E; Yang, Ching-Hong; Johnson, Alexis M; Petrossian, Tanya C; Lum, Pek Y

    2014-01-01

    Shiga toxin-producing E. coli O157:H7 and non-O157 have been implicated in many foodborne illnesses caused by the consumption of contaminated fresh produce. However, data on their persistence in soils are limited due to the complexity in datasets generated from different environmental variables and bacterial taxa. There is a continuing need to distinguish the various environmental variables and different bacterial groups to understand the relationships among these factors and the pathogen survival. Using an approach called Topological Data Analysis (TDA); we reconstructed the relationship structure of E. coli O157 and non-O157 survival in 32 soils (16 organic and 16 conventionally managed soils) from California (CA) and Arizona (AZ) with a multi-resolution output. In our study, we took a community approach based on total soil microbiome to study community level survival and examining the network of the community as a whole and the relationship between its topology and biological processes. TDA produces a geometric representation of complex data sets. Network analysis showed that Shiga toxin negative strain E. coli O157:H7 4554 survived significantly longer in comparison to E. coli O157:H7 EDL 933, while the survival time of E. coli O157:NM was comparable to that of E. coli O157:H7 EDL 933 in all of the tested soils. Two non-O157 strains, E. coli O26:H11 and E. coli O103:H2 survived much longer than E. coli O91:H21 and the three strains of E. coli O157. We show that there are complex interactions between E. coli strain survival, microbial community structures, and soil parameters.

  20. Genetic characterization of Shiga toxin-producing Escherichia coli (STEC) and atypical enteropathogenic Escherichia coli (EPEC) isolates from goat's milk and goat farm environment.

    PubMed

    Álvarez-Suárez, María-Elena; Otero, Andrés; García-López, María-Luisa; Dahbi, Ghizlane; Blanco, Miguel; Mora, Azucena; Blanco, Jorge; Santos, Jesús A

    2016-11-01

    The aim of this study was to characterize a collection of 44 Shiga toxin-producing (STEC) and enteropathogenic Escherichia coli (EPEC) isolated from goat milk and goat farm environment. Of the 19 STEC isolates, five (26.3%) carried the stx1 gene, four (21.1%) the stx2 gene and 10 (52.6%) presented both stx genes. Six (31.6%) STEC strains were eae-positive and belonged to serotypes related to severe human disease (O157:H7 and O5:HNM). Another seven STEC strains were of serotype O146:H21 and three of serotype O166:H28, also linked to human disease. The STEC strains isolated from goat milk were of serotypes potentially pathogenic for humans. All the 25 EPEC isolates were considered atypical (aEPEC) and one aEPEC strain was of serotype O26:H11, a serotype frequently isolated in children with diarrhea. Multilocus sequence typing (MLST) was carried out with seven housekeeping genes and 23 sequence types (ST) were detected, 14 of them newly described. Twelve STs grouped STEC isolates and 11 STs grouped EPEC isolates. Genetic typing by pulsed field gel electrophoresis (PFGE) resulted in 38 patterns which grouped in 10 clusters. Well-defined groups were also observed for strains of pathogenic serotypes. In conclusion, strains of STEC and aEPEC belonging to serotypes related to severe human disease have been detected in goat milk and the goat farm environment. Ruminants are an important reservoir of STEC strains and the role of these animals as carriers of other pathogenic types of E. coli seems to be an emerging concern. PMID:27497630

  1. Protection against Shiga-Toxigenic Escherichia coli by Non-Genetically Modified Organism Receptor Mimic Bacterial Ghosts

    PubMed Central

    Paton, Adrienne W.; Chen, Austen Y.; Wang, Hui; McAllister, Lauren J.; Höggerl, Florian; Mayr, Ulrike Beate; Shewell, Lucy K.; Jennings, Michael P.; Morona, Renato; Lubitz, Werner

    2015-01-01

    Shiga-toxigenic Escherichia coli (STEC) causes severe gastrointestinal infections in humans that may lead to life-threatening systemic sequelae, such as the hemolytic uremic syndrome (HUS). Rapid diagnosis of STEC infection early in the course of disease opens a window of opportunity for therapeutic intervention, for example, by administration of agents that neutralize Shiga toxin (Stx) in the gut lumen. We previously developed a recombinant bacterium that expresses a mimic of the Stx receptor globotriaosyl ceramide (Gb3) on its surface through modification of the lipopolysaccharide (A. W. Paton, R. Morona, and J. C. Paton, Nat Med 6:265–270, 2000, http://dx.doi.org/10.1038/73111). This construct was highly efficacious in vivo, protecting mice from otherwise fatal STEC disease, but the fact that it is a genetically modified organism (GMO) has been a barrier to clinical development. In the present study, we have overcome this issue by development of Gb3 receptor mimic bacterial ghosts (BGs) that are not classified as GMOs. Gb3-BGs neutralized Stx1 and Stx2 in vitro with high efficiency, whereas alternative Gb3-expressing non-GMO subbacterial particles (minicells and outer membrane blebs) were ineffective. Gb3-BGs were highly efficacious in a murine model of STEC disease. All mice (10/10) treated with Gb3-BGs survived challenge with a highly virulent O113:H21 STEC strain and showed no pathological signs of renal injury. In contrast, 6/10 mice treated with control BGs succumbed to STEC challenge, and survivors exhibited significant weight loss, neutrophilia, and histopathological evidence of renal damage. Thus, Gb3-BGs offer a non-GMO approach to treatment of STEC infection in humans, particularly in an outbreak setting. PMID:26099582

  2. Methanogenesis produces strong 13C enrichment in stromatolites of Lagoa Salgada, Brazil: a modern analogue for Palaeo-/Neoproterozoic stromatolites?

    PubMed

    Birgel, D; Meister, P; Lundberg, R; Horath, T D; Bontognali, T R R; Bahniuk, A M; de Rezende, C E; Vasconcelos, C; McKenzie, J A

    2015-05-01

    Holocene stromatolites characterized by unusually positive inorganic δ(13) CPDB values (i.e. up to +16‰) are present in Lagoa Salgada, a seasonally brackish to hypersaline lagoon near Rio de Janeiro (Brazil). Such positive values cannot be explained by phototrophic fixation of CO2 alone, and they suggest that methanogenesis was a dominating process during the growth of the stromatolites. Indeed, up to 5 mm methane was measured in the porewater. The archaeal membrane lipid archaeol showing δ(13) C values between -15 and 0‰ suggests that archaea are present and producing methane in the modern lagoon sediment. Moreover, (13) C-depleted hopanoids diplopterol and 3β-methylated C32 17β(H),21β(H)-hopanoic acid (both -40‰) are preserved in lagoon sediments and are most likely derived from aerobic methanotrophic bacteria thriving in the methane-enriched water column. Loss of isotopically light methane through the water column would explain the residual (13) C-enriched pool of dissolved inorganic carbon from where the carbonate constituting the stromatolites precipitated. The predominance of methanogenic archaea in the lagoon is most likely a result of sulphate limitation, suppressing the activity of sulphate-reducing bacteria under brackish conditions in a seasonally humid tropical environment. Indeed, sulphate-reduction activity is very low in the modern sediments. In absence of an efficient carbonate-inducing metabolic process, we propose that stromatolite formation in Lagoa Salgada was abiotically induced, while the (13) C-enriched organic and inorganic carbon pools are due to methanogenesis. Unusually, (13) C-enriched stromatolitic deposits also appear in the geological record of prolonged periods in the Palaeo- and Neoproterozoic. Lagoa Salgada represents a possible modern analogue to conditions that may have been widespread in the Proterozoic, at times when low sulphate concentrations in sea water allowed methanogens to prevail over sulphate

  3. Myocardialization of the cardiac outflow tract

    NASA Technical Reports Server (NTRS)

    van den Hoff, M. J.; Moorman, A. F.; Ruijter, J. M.; Lamers, W. H.; Bennington, R. W.; Markwald, R. R.; Wessels, A.

    1999-01-01

    During development, the single-circuited cardiac tube transforms into a double-circuited four-chambered heart by a complex process of remodeling, differential growth, and septation. In this process the endocardial cushion tissues of the atrioventricular junction and outflow tract (OFT) play a crucial role as they contribute to the mesenchymal components of the developing septa and valves in the developing heart. After fusion, the endocardial ridges in the proximal portion of the OFT initially form a mesenchymal outlet septum. In the adult heart, however, this outlet septum is basically a muscular structure. Hence, the mesenchyme of the proximal outlet septum has to be replaced by cardiomyocytes. We have dubbed this process "myocardialization." Our immunohistochemical analysis of staged chicken hearts demonstrates that myocardialization takes place by ingrowth of existing myocardium into the mesenchymal outlet septum. Compared to other events in cardiac septation, it is a relatively late process, being initialized around stage H/H28 and being basically completed around stage H/H38. To unravel the molecular mechanisms that are responsible for the induction and regulation of myocardialization, an in vitro culture system in which myocardialization could be mimicked and manipulated was developed. Using this in vitro myocardialization assay it was observed that under the standard culture conditions (i) whole OFT explants from stage H/H20 and younger did not spontaneously myocardialize the collagen matrix, (ii) explants from stage H/H21 and older spontaneously formed extensive myocardial networks, (iii) the myocardium of the OFT could be induced to myocardialize and was therefore "myocardialization-competent" at all stages tested (H/H16-30), (iv) myocardialization was induced by factors produced by, most likely, the nonmyocardial component of the outflow tract, (v) at none of the embryonic stages analyzed was ventricular myocardium myocardialization-competent, and finally

  4. Metabolomics-Based Analysis of Banana and Pear Ingestion on Exercise Performance and Recovery.

    PubMed

    Nieman, David C; Gillitt, Nicholas D; Sha, Wei; Meaney, Mary Pat; John, Casey; Pappan, Kirk L; Kinchen, Jason M

    2015-12-01

    Bananas and pears vary in sugar and phenolic profiles, and metabolomics was utilized to measure their influence on exercise performance and recovery. Male athletes (N = 20) cycled for 75 km while consuming water (WATER), bananas (BAN), or pears (PEAR) (0.6 g carbohydrate/kg each hour) in randomized order. UPLC-MS/MS and the library of purified standards maintained by Metabolon (Durham, NC) were used to analyze metabolite shifts in pre- and postexercise (0-h, 1.5-h, 21-h) blood samples. Performance times were 5.0% and 3.3% faster during BAN and PEAR versus WATER (P = 0.018 and P = 0.091, respectively), with reductions in cortisol, IL-10, and total leukocytes, and increases in blood glucose, insulin, and FRAP. Partial Least Square Discriminant Analysis (PLS-DA) showed a distinct separation between trials immediately (R(2)Y = 0.877, Q(2)Y = 0.457) and 1.5-h postexercise (R(2)Y = 0.773, Q(2)Y = 0.441). A total of 107 metabolites (primarily lipid-related) increased more than 2-fold during WATER, with a 48% and 52% reduction in magnitude during BAN and PEAR recovery (P < 0.001). Increases in metabolites unique to BAN and PEAR included fructose and fruit constituents, and sulfated phenolics that were related to elevated FRAP. These data indicate that BAN and PEAR ingestion improves 75-km cycling performance, attenuates fatty acid utilization and oxidation, and contributes unique phenolics that augment antioxidant capacity.

  5. The Abundance of Deuterium in the Warm Neutral Medium of the Lower Galactic Halo

    NASA Astrophysics Data System (ADS)

    Savage, Blair D.; Lehner, Nicolas; Fox, Andrew; Wakker, Bart; Sembach, Kenneth

    2007-04-01

    We use high-resolution ultraviolet spectra to obtain Milky Way interstellar column densities of H I, D I, O I, S II, Fe II, and P II toward the QSO HE 0226-4110 in the Galactic direction l=253.4deg and b=-65.77deg. We obtain D/H=21+8-6 ppm from an analysis of the strong damped Lyα line of H I and the weak higher Lyman series absorption of D I. Correcting for a small amount of foreground contamination from D and H in the Local Bubble we obtain D/H=22+8-6 for the warm neutral medium of the lower Galactic halo. The medium sampled has [O/H]=0.12+0.41-0.20 and [Fe/H]=-1.01+0.10-0.09. This suggests the abundances in the gas in the halo toward HE 0226-4110 are not affected by the infall of low-metallicity gas and that the gas originates in the disk and is elevated into the halo by energetic processes that erode but do not totally destroy the dust grains. We compare our result to measured values of D/H in other astrophysical sites. The value we measure in the halo gas is consistent with the hypothesis that for many Galactic disk lines of sight D is incorporated into dust. The high average value of D/H=23.1+/-2.4(1 σ) ppm measured along five sight lines through disk gas in the solar neighborhood is similar to D/H in the lower Galactic halo. These disk and halo observations imply the abundance of deuterium in the Galaxy has only been reduced by a factor of 1.12+/-0.13 since its formation. In contrast, current galactic chemical evolution models predict the astration reduction factor should be in the range from 1.39 to 1.83.

  6. Photometric redshifts and clustering of emission line galaxies selected jointly by DES and eBOSS

    SciTech Connect

    Jouvel, S.; et al.

    2015-09-23

    We present the results of the first test plates of the extended Baryon Oscillation Spectroscopic Survey. This paper focuses on the emission line galaxies (ELG) population targetted from the Dark Energy Survey (DES) photometry. We analyse the success rate, efficiency, redshift distribution, and clustering properties of the targets. From the 9000 spectroscopic redshifts targetted, 4600 have been selected from the DES photometry. The total success rate for redshifts between 0.6 and 1.2 is 71\\% and 68\\% respectively for a bright and faint, on average more distant, samples including redshifts measured from a single strong emission line. We find a mean redshift of 0.8 and 0.87, with 15 and 13\\% of unknown redshifts respectively for the bright and faint samples. In the redshift range 0.6h < -21.0. We note that biasing is derived from the galaxy clustering relative to a model for the mass fluctuations. We investigate the quality of the DES photometric redshifts and find that the outlier fraction can be reduced using a comparison between template fitting and neural network, or using a random forest algorithm.

  7. Study of the mineralization effect on the distribution of lipids in sediments from the Cretan Sea: Evidence for hydrocarbon degradation and starvation stress

    NASA Astrophysics Data System (ADS)

    Polymenakou, Paraskevi N.; Tselepides, Anastasios; Stephanou, Euripides G.

    2005-11-01

    Sedimentary diagenetic processes alter the composition and distribution of different lipid compounds. In the present study alterations mediated by microbial communities were investigated along a bathymetric gradient (100 m at 35°23'N-25°09'E, 617 m at 35°33'N-25°08'E, 1494 m at 35°44'N-25°08'E) over the continental margin of northern Crete (Greece, Eastern Mediterranean Sea). Bacterial abundances and distribution were studied using phospholipid linked fatty acids (PLFA), in the range of C 8-C 22, released from intact phospholipids. Lipid components (aliphatic hydrocarbons, free fatty acids, glycerides and glycolipids) were studied over a 2-month incubation period. Carbon mineralization rates at all stations indicated an uneven distribution of active aerobic bacteria with values decreasing towards the deeper stations. PLFA homologue profiles denoted that aerobic gram negative and sulfur oxidizing bacteria dominated microbial communities while the anaerobic, gram positive and sulfate reducing bacteria occurred only in traces. The n-alkane (NA) composition revealed a strong predominance of homologues with odd carbon numbers suggesting an important terrestrial contribution to the sediments. The estimated descriptive ratios of NA, the sum of short chain NA (C 15-C 20) and long chain NA (C 21-C 36) to 17 α( H),21 β( H)-C 30-hopane, before and after a two-month incubation period, indicated the occurrence of hydrocarbon degradation processes. Increased ratios of saturated to unsaturated fatty acids were also recorded after the incubation indicating the starvation of bacterial communities by the end of the experiments.

  8. η Carinae Baby Homunculus Uncovered by ALMA

    NASA Astrophysics Data System (ADS)

    Abraham, Zulema; Falceta-Gonçalves, Diego; Beaklini, Pedro P. B.

    2014-08-01

    We report observations of η Carinae obtained with ALMA in the continuum of 100, 230, 280, and 660 GHz in 2012 November, with a resolution that varied from 2.''88 to 0.''45 for the lower and higher frequencies, respectively. The source is not resolved, even at the highest frequency; its spectrum is characteristic of thermal bremsstrahlung of a compact source, but different from the spectrum of optically thin wind. The recombination lines H42α, He42α, H40α, He40α, H50β, H28α, He28α, H21α, and He21α were also detected, and their intensities reveal non-local thermodynamic equilibrium effects. We found that the line profiles could only be fit by an expanding shell of dense and ionized gas, which produces a slow shock in the surroundings of η Carinae. Combined with fittings to the continuum, we were able to constrain the shell size, radius, density, temperature, and velocity. The detection of the He recombination lines is compatible with the high-temperature gas and requires a high-energy ionizing photon flux, which must be provided by the companion star. The mass-loss rate and wind velocity, necessary to explain the formation of the shell, are compatible with an luminous blue variable eruption. The position, velocity, and physical parameters of the shell coincide with those of the Weigelt blobs. The dynamics found for the expanding shell correspond to matter ejected by η Carinae in 1941 in an event similar to that which formed the Little Homunculus; for that reason, we called the new ejecta the "Baby Homunculus."

  9. Studies on the hydrothermal modifications of new cocoyam (Xanthosoma sagittifolium) starch.

    PubMed

    Lawal, Olayide S

    2005-12-30

    Native new cocoyam starch (nNCS) was subjected to annealing (aNCS) and heat moisture treatment at 18% moisture level (h18NCS), 21% moisture level (h21NCS), 24% moisture level (h24NCS) and 27% moisture level (h27NCS) as hydrothermal treatments. Scanning electron and light microscopy revealed round and polygonal shapes with sizes ranging from 15 to 40 microm for native and modified starches. nNCS showed "A" pattern X-ray diffraction and no significant differences were observed in the X-ray pattern of the modified starches. Swelling power and solubility reduced following heat moisture treatment. At all pH studied (2-12), unmodified new cocoyam starch exhibited higher swelling capacity and solubility than the modified derivatives. Hydrothermal modifications improved water absorption capacity but reduced oil absorption capacity. Pasting temperature of native starch shifted to higher values following annealing and heat moisture treatment. Hot paste viscosity (Hv), viscosity after 30 min holding at 95 degrees C (Hv30) and cold paste viscosity (Cv) reduced after annealing and heat moisture treatment. The result also indicates that hydrothermal treatments reduced the tendency for setback. As the number of days of storage of starch paste increased from 1 to 10, light transmittance of all the starches reduced but marked reduction of light transmittance was observed in native starch. DSC studies revealed increase in gelatinization temperature following annealing and heat moisture treatment. Starch hydrothermal modifications reduced retrogradation as enthalpies of regelatinization reduced following modifications. The regelatinization peak in the second day scanning shifted to lower temperature than the gelatinization peak in first run heating DSC curve for all samples. The regelatinization peak also became larger and shifted to higher temperature range when the storage days increased from 2 to 7.

  10. Characteristics of particulate carbon emissions from real-world Chinese coal combustion

    SciTech Connect

    Yuanxun Zhang; James Jay Schauer; Yuanhang Zhang; Limin Zeng; Yongjie Wei; Yuan Liu; Min Shao

    2008-07-15

    Particulate matter emissions from a series of different Chinese coal combustion systems were collected and analyzed for elemental and organic carbon (EC, OC), and molecular markers. Emissions from both industrial boilers and residential stoves were investigated. The coal used in this study included anthracite, bituminite, and brown coal, as well as commonly used coal briquettes produced in China for residential coal combustion. Results show significant differences in the contribution of carbonaceous species to particulate mass emissions. Industrial boilers had much higher burn out of carbon yielding particulate matter emissions with much lower levels of OC, EC, and speciated organic compounds, while residential stoves had significantly higher emissions of carbonaceous particulate matter with emission rates of approximately 100 times higher than that of industrial boilers. Quantified organic compounds emitted from industrial boilers were dominated by oxygenated compounds, of which 46-68% were organic acids, whereas the dominate species quantified in the emissions from residential stoves were PAHs (38%) and n-alkanes (20%). An important observation was the fact that emission factors of PAHs and the distribution of hopanoids were different among the emissions from industrial and residential coal combustion even using the same coal for combustion. Although particulate matter emissions from industrial and residential combustion were different in many regards, picene was detected in all samples with detectable OC mass concentrations, which supports the use of this organic tracer for OC from all types of coal combustion. 17{alpha}(H),21{beta}(H)-29-norhopane was the predominant hopanoid in coal combustion emissions, which is different from mobile source emissions and may be used to distinguish emissions from these different fossil fuel sources. 32 refs., 4 figs., 1 tab.

  11. Crystal structures of (E)-3-(furan-2-yl)-2-phenyl-N-tosyl-acryl-amide and (E)-3-phenyl-2-(m-tol-yl)-N-tosyl-acryl-amide.

    PubMed

    Cheng, Dong; Meng, Xiangzhen; Sheng, Zeyuan; Wang, Shuangming; Duan, Yuanyuan; Li, Ziqian

    2016-06-01

    In the title N-tosyl-acryl-amide compounds, C20H17NO4S, (I), and C23H21NO3S, (II), the conformation about the C=C bond is E. The acryl-amide groups, [-NH-C(=O)-C=C-], are almost planar, with the N-C-C=C torsion angle being -170.18 (14)° in (I) and -168.01 (17)° in (II). In (I), the furan, phenyl and 4-methyl-benzene rings are inclined to the acryl-amide mean plane by 26.47 (11), 69.01 (8) and 82.49 (9)°, respectively. In (II), the phenyl, 3-methyl-benzene and 4-methyl-benzene rings are inclined to the acryl-amide mean plane by 11.61 (10), 78.44 (10) and 78.24 (10)°, respectively. There is an intra-molecular C-H⋯π inter-action present in compound (II). In the crystals of both compounds, mol-ecules are linked by pairs of N-H⋯O hydrogen bonds, forming inversion dimers with an R 2 (2)(8) ring motif. In (I), the dimers are reinforced by C-H⋯O hydrogen bonds and linked by C-H⋯π inter-actions, forming chains along [011]. In the crystal of (II), the dimers are linked via C-H⋯O hydrogen bonds, forming chains along [100]. The chains are further linked by C-H⋯π inter-actions, forming layers parallel to (010). PMID:27308045

  12. Erythrocyte sequestration and anemia in severe falciparum malaria. Analysis of acute changes in venous hematocrit using a simple mathematical model.

    PubMed Central

    Davis, T M; Krishna, S; Looareesuwan, S; Supanaranond, W; Pukrittayakamee, S; Attatamsoonthorn, K; White, N J

    1990-01-01

    Microvascular erythrocyte sequestration, the characteristic pathological feature of falciparum malaria, was evaluated using a mathematical model in 46 patients with severe infections. From admission radioisotopic circulating red cell volumes and simultaneous venous hematocrits, the model-derived sequestrum hematocrit (mean [95% confidence limits]: 0.70 [0.43-0.97], n = 29) was twice that of peripheral blood (0.33 [0.30-0.36]). Serial reticulocyte and radiolabeled erythrocyte counts indicated that small numbers of cells enter the circulation during initial therapy. The mean fall in hematocrit over 84 h in 26 nontransfused patients conformed to a three-term equation. A first-order decline (t1/2 2.0 h [0.6-3.4]) suggested an average 7.5% plasma volume expansion through rehydration. A zero-order 6.3% (3.1-9.5) fall (t1/2 25.7 h [21.2-30.2]) occurred contemporaneously with a fall in mean parasitemia from 4.5% (3.6-5.4); from these data the model-derived average sequestered erythrocyte volume (4.8% of the admission hematocrit) was similar to the peripheral parasite burden. A second, first-order fall (t1/2 1,047 h [278-1,816]) indicated loss of uninfected erythrocytes with mean lifespan 62 d. Predicted total plasma volume expansion during initial therapy (21.2%) was similar to radioisotopic estimates in 11 patients (17.3% [2.0-33.1]). Application of the model to individual patient data showed wide variations in relative proportions of circulating and sequestered parasitized cells. The model provides evidence of the nature and fate of all parasitized erythrocytes in malaria. PMID:2203822

  13. Topological data analysis of Escherichia coli O157:H7 and non-O157 survival in soils

    PubMed Central

    Ibekwe, Abasiofiok M.; Ma, Jincai; Crowley, David E.; Yang, Ching-Hong; Johnson, Alexis M.; Petrossian, Tanya C.; Lum, Pek Y.

    2014-01-01

    Shiga toxin-producing E. coli O157:H7 and non-O157 have been implicated in many foodborne illnesses caused by the consumption of contaminated fresh produce. However, data on their persistence in soils are limited due to the complexity in datasets generated from different environmental variables and bacterial taxa. There is a continuing need to distinguish the various environmental variables and different bacterial groups to understand the relationships among these factors and the pathogen survival. Using an approach called Topological Data Analysis (TDA); we reconstructed the relationship structure of E. coli O157 and non-O157 survival in 32 soils (16 organic and 16 conventionally managed soils) from California (CA) and Arizona (AZ) with a multi-resolution output. In our study, we took a community approach based on total soil microbiome to study community level survival and examining the network of the community as a whole and the relationship between its topology and biological processes. TDA produces a geometric representation of complex data sets. Network analysis showed that Shiga toxin negative strain E. coli O157:H7 4554 survived significantly longer in comparison to E. coli O157:H7 EDL 933, while the survival time of E. coli O157:NM was comparable to that of E. coli O157:H7 EDL 933 in all of the tested soils. Two non-O157 strains, E. coli O26:H11 and E. coli O103:H2 survived much longer than E. coli O91:H21 and the three strains of E. coli O157. We show that there are complex interactions between E. coli strain survival, microbial community structures, and soil parameters. PMID:25250242

  14. Use of a Shiga toxin (Stx)-enzyme-linked immunosorbent assay and immunoblot for detection and isolation of Stx-producing Escherichia coli from naturally contaminated beef.

    PubMed

    Atalla, H N; Johnson, R; McEwen, S; Usborne, R W; Gyles, C L

    2000-09-01

    The purpose of this study was to evaluate an enzyme-linked immunosorbent assay (ELISA) and an immunoblot procedure for detection and isolation of Shiga toxin-producing Escherichia coli (STEC) from beef, and to correlate the presence of STEC in beef with E. coli and total coliform counts. A total of 120 samples of boneless beef supplied to a meat processor in southern Ontario were tested for the presence of STEC, E. coli, and total coliforms. Following enrichment in modified tryptic soy broth, samples were screened for Shiga toxin (Stx) by a Stx-ELISA and a Vero cell assay (VCA). Samples that were positive in the Stx-ELISA were subjected to the Stx-immunoblot for STEC isolation. Overall, 33.3% of samples were positive in the VCA, and 34.2% were positive in the Stx-ELISA. There was almost complete agreement between the Stx-ELISA and the VCA results (kappa = 0.98). The sensitivity and specificity of the Stx-ELISA with respect to the VCA were 100% and 98.75%, respectively. STEC were isolated by the Stx-immunoblot from 87.8% of the samples that were positive in the Stx-ELISA. The STEC isolates belonged to 19 serotypes, with serotype O113:H21 accounting for 10 of 41 isolates. No STEC of serotype O157:H7 were isolated. There was a significant correlation between E. coli counts and total coliform counts (Spearman correlation coefficient = 0.68, P < 0.01). The E. coli count was positively correlated with detection of STEC by both the Stx-ELISA and the VCA (P < 0.01).

  15. Involvement of the nervous system following experimental infection with Pasteurella multocida B:2 in buffalo (Bubalus bubalis): A clinicopathological study.

    PubMed

    Marza, Ali Dhiaa; Jesse, Faez Firdaus Abdullah; Ahmed, Ihsan Muneer; Chung, Eric Lim Teik; Ibrahim, Hayder Hamzah; Zamri-Saad, Mohd; Omar, Abdul Rahman; Abu Bakar, Md Zuki; Saharee, Abdul Aziz; Haron, Abdul Wahid; Alwan, Mohammed Jwaid; Lila, Mohd Azmi Mohd

    2016-04-01

    Haemorrhagic septicaemia (HS) is an acute, fatal, septicaemic disease of cattle and buffaloes caused by one of two specific serotypes of Pasteurella multocida B:2 and E:2 in Asian and African, respectively. It is well known that HS affect mainly the respiratory and digestive tracts. However, involvement of the nervous system in pathogenesis of HS has been reported in previous studies without details. In this study, nine buffalo calves of 8 months old were distributed into three groups. Animals of Group 1 and 2 were inoculated orally and subcutaneously with 10 ml of 1 × 10(12) cfu/ml of P. multocida B:2, respectively, while animals of Group 3 were inoculated orally with 10 ml of phosphate buffer saline as a control. All calves in Group 1 and Group 3 were euthanised after 504 h (21 day) post-infection, while calves in Group 2 had to euthanise after 12 h post-infection as they develop sever clinical signs of HS. Significant differences were found in Group 2 in the mean scores of clinical signs, gross and histopathological changes which mainly affect different anatomic regions of the nervous system. In addition, successful bacterial isolation of P. multocida B:2 were obtained from different sites of the nervous system. On the other hand, less sever, clinical, gross and histopathological changes were found in Group 1. These results provide for the first time strong evidence of involving of the nervous system in pathogenesis of HS, especially in the peracute stage of the disease. PMID:26850845

  16. Early attachment sites for Shiga-toxigenic Escherichia coli O157:H7 in experimentally inoculated weaned calves.

    PubMed

    Dean-Nystrom, Evelyn A; Stoffregen, William C; Bosworth, Brad T; Moon, Harley W; Pohlenz, Joachim F

    2008-10-01

    Weaned 3- to 4-month-old calves were fasted for 48 h, inoculated with 10(10) CFU of Shiga toxin-positive Escherichia coli (STEC) O157:H7 strain 86-24 (STEC O157) or STEC O91:H21 strain B2F1 (STEC O91), Shiga toxin-negative E. coli O157:H7 strain 87-23 (Stx(-) O157), or a nonpathogenic control E. coli strain, necropsied 4 days postinoculation, and examined bacteriologically and histologically. Some calves were treated with dexamethasone (DEX) for 5 days (3 days before, on the day of, and 1 day after inoculation). STEC O157 bacteria were recovered from feces, intestines, or gall bladders of 74% (40/55) of calves 4 days after they were inoculated with STEC O157. Colon and cecum were sites from which inoculum-type bacteria were most often recovered. Histologic lesions of attaching-and-effacing (A/E) O157(+) bacteria were observed in 69% (38/55) of the STEC O157-inoculated calves. Rectum, ileocecal valve, and distal colon were sites most likely to contain A/E O157(+) bacteria. Fecal and intestinal levels of STEC O157 bacteria were significantly higher and A/E O157(+) bacteria were more common in DEX-treated calves than in nontreated calves inoculated with STEC O157. Fecal STEC O157 levels were significantly higher than Stx(-) O157, STEC O91, or control E. coli; only STEC O157 cells were recovered from tissues. Identifying the rectum, ileocecal valve, and distal colon as early STEC O157 colonization sites and finding that DEX treatment enhances the susceptibility of weaned calves to STEC O157 colonization will facilitate the identification and evaluation of interventions aimed at reducing STEC O157 infection in cattle. PMID:18723644

  17. Design of N-doped anatase TiO2 photocatalyst with visible-light-response based on Ti-O bond weakening

    NASA Astrophysics Data System (ADS)

    Yin, L.-C.; Liu, G.; Cheng, H.-M.; Advanced Carbon Division Team

    2013-03-01

    Nitrogen bulk doping is an effective strategy to change the electronic structures of anatase TiO2 photocatalyst for visible light response improvement. Unfortunately, it is hard to achieve nitrogen bulk doping in practice, due to both limited thermodynamic solubility of substitutional nitrogen and N-induced recombination centers. It remains challenging yet highly desirable to develop new doping approach to increase nitrogen solubility in bulk. This challenge is originally stemmed from both strong Ti-O bond and charge difference (O2- versus N3-) between lattice oxygen and nitrogen dopant. In this work, we propose a new doping approach to promote the bulk substitution of lattice oxygen with nitrogen in bulk anatase TiO2, based on the Ti-O bond weakening by pre-implanted interstitial boron.1 By using the first-principles calculations, we study the interstitial boron induced Ti-O bonding weakening and the thermodynamics/kinetics changes for nitrogen bulk doping.2 In experiment, we realize to synthesize a bulk gradient B-N co-doping red anatase TiO2 microsphere which has an extended absorption edge up to ca. 700 nm covering the full visible light spectrum and has a bandgap varying from 1.94 eV on its surface to 3.22 eV in its core by gradually elevating VBM. This approach could be extended to modify other electronic materials that demand bulk substitutional doping. 1. G. Liu, J. Pan, L. C. Yin et al., Adv. Funct. Mater., 2012, 22, 3233. 2. G. Liu, L. C. Yin, J. Q. Wang et al., Energy Environ. Sci. 2012, 5, 9603. Financial support from Ministry of Science and Technology of China (no. 2009CB220001), NSFC (no. 50921004, 51002160, 21090343, 51172243, 51202255), CAS China (KJCX2-YW-H21-01).

  18. Differential gene expression in Staphylococcus aureus exposed to Orange II and Sudan III azo dyes.

    PubMed

    Pan, Hongmiao; Xu, Joshua; Kweon, Oh-Gew; Zou, Wen; Feng, Jinhui; He, Gui-Xin; Cerniglia, Carl E; Chen, Huizhong

    2015-05-01

    We previously demonstrated the effects of azo dyes and their reduction metabolites on bacterial cell growth and cell viability. In this report, the effects of Orange II and Sudan III on gene expression profiling in Staphylococcus aureus ATCC BAA 1556 were analyzed using microarray and quantitative RT-PCR technology. Upon exposure to 6 μg/ml Orange II for 18 h, 21 genes were found to be differently expressed. Among them, 8 and 13 genes were up- and down-regulated, respectively. Most proteins encoded by these differentially expressed genes involve stress response caused by drug metabolism, oxidation, and alkaline shock indicating that S. aureus could adapt to Orange II exposure through a balance between up and down regulated gene expression. Whereas, after exposure to 6 μg/ml Sudan III for 18 h, 57 genes were differentially expressed. In which, 51 genes were up-regulated and 6 were down-regulated. Most proteins encoded by these differentially expressed genes involve in cell wall/membrane biogenesis and biosynthesis, nutrient uptake, transport and metabolite, and stress response, suggesting that Sudan III damages the bacterial cell wall or/and membrane due to binding of the dye. Further analysis indicated that all differentially expressed genes encoded membrane proteins were up-regulated and most of them serve as transporters. The result suggested that these genes might contribute to survival, persistence and growth in the presence of Sudan III. Only one gene msrA, which plays an important role in oxidative stress resistance, was found to be down-regulated after exposure to both Orange II and Sudan III. The present results suggested that both these two azo dyes can cause stress in S. aureus and the response of the bacterium to the stress is mainly related to characteristics of the azo dyes.

  19. Different molecular conformations co-exist in each of three 2-aryl-N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)acetamides: hydrogen bonding in zero, one and two dimensions.

    PubMed

    Narayana, Badiadka; Yathirajan, Hemmige S; Rathore, Ravindranath S; Glidewell, Christopher

    2016-09-01

    4-Antipyrine [4-amino-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one] and its derivatives exhibit a range of biological activities, including analgesic, antibacterial and anti-inflammatory, and new examples are always of potential interest and value. 2-(4-Chlorophenyl)-N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)acetamide, C19H18ClN3O2, (I), crystallizes with Z' = 2 in the space group P\\overline{1}, whereas its positional isomer 2-(2-chlorophenyl)-N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)acetamide, (II), crystallizes with Z' = 1 in the space group C2/c; the molecules of (II) are disordered over two sets of atomic sites having occupancies of 0.6020 (18) and 0.3980 (18). The two independent molecules of (I) adopt different molecular conformations, as do the two disorder components in (II), where the 2-chlorophenyl substituents adopt different orientations. The molecules of (I) are linked by a combination of N-H...O and C-H...O hydrogen bonds to form centrosymmetric four-molecule aggregates, while those of (II) are linked by the same types of hydrogen bonds forming sheets. The related compound N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)-2-(3-methoxyphenyl)acetamide, C20H21N3O3, (III), is isomorphous with (I) but not strictly isostructural; again the two independent molecules adopt different molecular conformations, and the molecules are linked by N-H...O and C-H...O hydrogen bonds to form ribbons. Comparisons are made with some related structures, indicating that a hydrogen-bonded R2(2)(10) ring is the common structural motif. PMID:27585929

  20. η Carinae Baby Homunculus uncovered by ALMA

    SciTech Connect

    Abraham, Zulema; Beaklini, Pedro P. B.; Falceta-Gonçalves, Diego

    2014-08-20

    We report observations of η Carinae obtained with ALMA in the continuum of 100, 230, 280, and 660 GHz in 2012 November, with a resolution that varied from 2.''88 to 0.''45 for the lower and higher frequencies, respectively. The source is not resolved, even at the highest frequency; its spectrum is characteristic of thermal bremsstrahlung of a compact source, but different from the spectrum of optically thin wind. The recombination lines H42α, He42α, H40α, He40α, H50β, H28α, He28α, H21α, and He21α were also detected, and their intensities reveal non-local thermodynamic equilibrium effects. We found that the line profiles could only be fit by an expanding shell of dense and ionized gas, which produces a slow shock in the surroundings of η Carinae. Combined with fittings to the continuum, we were able to constrain the shell size, radius, density, temperature, and velocity. The detection of the He recombination lines is compatible with the high-temperature gas and requires a high-energy ionizing photon flux, which must be provided by the companion star. The mass-loss rate and wind velocity, necessary to explain the formation of the shell, are compatible with an luminous blue variable eruption. The position, velocity, and physical parameters of the shell coincide with those of the Weigelt blobs. The dynamics found for the expanding shell correspond to matter ejected by η Carinae in 1941 in an event similar to that which formed the Little Homunculus; for that reason, we called the new ejecta the 'Baby Homunculus'.

  1. RED-SEQUENCE GALAXIES AT HIGH REDSHIFT BY THE COMBO-17+4 SURVEY

    SciTech Connect

    Nicol, Marie-Helene; Meisenheimer, Klaus; Wolf, Christian; Tapken, Christian E-mail: meise@mpia.de E-mail: ctapken@aip.de

    2011-01-20

    We investigate the evolution of the galaxy population since redshift 2 with a focus on the color bimodality and mass density of the red sequence. We obtain precise and reliable photometric redshifts up to z = 2 by supplementing the optical survey COMBO-17 with observations in four near-infrared bands on 0.2 deg{sup 2} of the COMBO-17 A901-field. Our results are based on an H-band-selected catalog of 10,692 galaxies complete to H = 21fm7. We measure the rest-frame color (U{sub 280}-V) of each galaxy, which across the redshift range of our interest requires no extrapolation and is robust against moderate redshift errors by staying clear of the 4000 A break. We measure the color-magnitude relation of the red sequence as a function of look-back time from the peak in a color-error-weighted histogram, and thus trace the galaxy bimodality out to z {approx_equal} 1.65. The (U{sub 280}-V) of the red sequence is found to evolve almost linearly with look-back time. At high redshift, we find massive galaxies in both the red and the blue population. Red-sequence galaxies with log M{sub *}/M{sub sun}>11 increase in mass density by a factor of {approx}4 from z {approx} 2 to 1 and remain nearly constant at z < 1. However, some galaxies as massive as log M{sub *}/M{sub sun} = 11.5 are already in place at z {approx} 2.

  2. Sedimentary lipid biogeochemistry of an hypereutrophic alkaline lagoon

    NASA Astrophysics Data System (ADS)

    Grimalt, J. O.; Yruela, I.; Saiz-Jimenez, C.; Toja, J.; de Leeuw, J. W.; Albaigés, J.

    1991-09-01

    A detailed study of the lipid composition of sedimentary and water particulate samples of a dilute alkaline lake (Santa Olalla Lagoon, Guadalquivir Delta, southwestern Spain) has allowed the identification and quantitation of about 300 compounds reflecting predominant inputs of organic matter and very early diagenetic processes. These lipids, dominated by fatty acids (80-86%), account for up to 0.25% wt. of dry sediment which is consistent with the high eutrophic conditions of the lagoon and suggests a good preservation of the originally produced organic matter. However, the primary lipid compounds, mainly from cyanobacterial origin, are strongly modified. The C30-C32, 1,13- and 1,15-diols constitute the only major group that can be attributed directly to these organisms. The predominant lipids, including the fatty acids, are indicative of intense microbial reworking, namely contributions from gram-positive and gram-negative eubacteria and methanogens. Conversely, the higher plant lipids are better preserved and dominate the aliphatic hydrocarbon fraction. Hydrogenation and dehydration are two major transformation processes in the sedimentary system being reflected in the transformation of sterols into 5α(H)- and 5β(H)-stanols and sterenes, and 17β(H),21β(H)-hopan-22-ol into diploptene. Oxidation in the water column seems to involve the partial transformation of sterols into steroid ketones, phytol into 5,9,13-trimethyltetradecanoic acid and two isomeric 3,7,11,15-tetramethyl-17-hexadecanolides, and, possibly, tetrahymanol into gammacer-3-one. Adiantone and bishomohopanoic acid probably result from the partial oxydation of extended polyhydroxyhopanes or the C30-C33 hydroxyhopanes found in the lagoon waters.

  3. Sedimentary lipid biogeochemistry of an hypereutrophic alkaline lagoon

    SciTech Connect

    Grimalt, J.O.; Albaiges, J. ); Yruela, I.; Saizjimenez, C. ); Toja, J. ); Leeuw, J.W. De. )

    1991-09-01

    A detailed study of the lipid composition of sedimentary and water particulate samples of a dilute alkaline lake (Santa Olalla Lagoon, Guadalquivir Delta, southwestern Spain) has allowed the identification and quantitation of about 300 compounds reflecting predominant inputs of organic matter and very early diagenetic processes. These lipids, dominated by fatty acids (80-86%), account for up to 0.25% wt. of dry sediment which is consistent with the high eutrophic conditions of the lagoon and suggests a good preservation of the originally produced organic matter. However, the primary lipid compounds, mainly from cyanobacterial origin, are strongly modified. The C{sub 30}-C{sub 32}, 1,13- and 1,15-diols constitute the only major group that can be attributed directly to these organisms. The predominant lipids, including the fatty acids, are indicative of intense microbial reworking, namely contributions from gram-positive and gram-negative eubacteria and methanogens. Conversely, the higher plant lipids are better preserved and dominate the aliphatic hydrocarbon fraction. Hydrogenation and dehydration are two major transformation processes in the sedimentary system being reflected in the transformation of sterols into 5{alpha}(H)- and 5{beta}(H)-stanols and sterenes, and 17{beta}(H), 21{beta}(H)-hopan-22-ol into diploptene. Oxidation in the water column seems to involve the partial transformation of sterols into steroid ketones, phytol into 5,9,13-trimethyltetradecanoic acid and two isomeric 3,7,11,15-tetramethyl-17-hexadecanolides, and, possibly, tetrahymanol into gammacer-3-one. Adiantone and bishomohopanoic acid probably result from the partial oxydation of extended polyhydroxyhopanes or the C{sub 30}-C{sub 33} hydroxyhopanes found in the lagoon waters.

  4. New insights into the mechanism of dihydrodipicolinate synthase using isothermal titration calorimetry.

    PubMed

    Muscroft-Taylor, Andrew C; Soares da Costa, Tatiana P; Gerrard, Juliet A

    2010-03-01

    Thermodynamic binding information, obtained via isothermal titration calorimetry (ITC), provides new insights into the binding of substrates, and of allosteric inhibitor interactions of dihydrodipicolinate synthase (DHDPS) from Escherichia coli. DHDPS catalyses the first committed step in (S)-lysine biosynthesis: the Schiff-base mediated aldol condensation of pyruvate with (S)-aspartate semi-aldehyde. Binding studies indicate that pyruvate is a weak binder (0.023 mM) but that (S)-ASA does not interact with the enzyme in the absence of a Schiff-base with pyruvate. These results support the assignment of a ping pong catalytic mechanism in which enthalpically driven Schiff-base formation (DeltaH = -44.5 +/- 0.1 kJ mol(-1)) provides the thermodynamic impetus for pyruvate association. The second substrate, (S)-ASA, was observed to bind to a Schiff-base mimic (DeltaH = -2.8 +/- 0.1 kJ mol(-1)) formed through the reduction of the intermediate pyruvyl-Schiff-base complex. The binding interaction of (S)-lysine was characterised as a cooperative event in which an entropic pre-organisation step (TDeltaS = 17.6 +/- 1.1 kJ mol(-1)) precedes a secondary enthalpic association (DeltaH = -21.6 +/- 0.2 kJ mol(-1)). This allosteric association was determined to be of a mixed competitive nature in which heterotropic ligand cooperativity was observed to subtly influence the binding events. These results offer new insights into the inhibition of this enzyme, a validated antibiotic target.

  5. Recalcitrance and degradation of petroleum biomarkers upon abiotic and biotic natural weathering of Deepwater Horizon oil.

    PubMed

    Aeppli, Christoph; Nelson, Robert K; Radović, Jagoš R; Carmichael, Catherine A; Valentine, David L; Reddy, Christopher M

    2014-06-17

    Petroleum biomarkers such as hopanoids, steranes, and triaromatic steroids (TAS) are commonly used to investigate the source and fate of petroleum hydrocarbons in the environment based on the premise that these compounds are resistant to biotic and abiotic degradation. To test the validity of this premise in the context of the Deepwater Horizon disaster, we investigated changes to these biomarkers as induced by natural weathering of crude oil discharged from the Macondo Well (MW). For surface slicks collected from May to June in 2010, and other oiled samples collected on beaches in the northern Gulf of Mexico from July 2010 until August 2012, hopanoids with up to 31 carbons as well as steranes and diasteranes were not systematically affected by weathering processes. In contrast, TAS and C32- to C35-homohopanes were depleted in all samples relative to 17α(H),21β(H)-hopane (C30-hopane). Compared to MW oil, C35-homohopanes and TAS were depleted by 18 ± 10% and 36 ± 20%, respectively, in surface slicks collected from May to June 2010, and by 37 ± 9% and 67 ± 10%, respectively, in samples collected along beaches from April 2011 through August 2012. Based on patterns of relative losses of individual compounds, we hypothesize biodegradation and photooxidation as main degradation processes for homohopanes and TAS, respectively. This study highlights that (i) TAS and homohopanes can be degraded within several years following an oil spill, (ii) the use of homohopanes and TAS for oil spill forensics must account for degradation, and (iii) these compounds provide a window to parse biodegradation and photooxidation during advanced stages of oil weathering.

  6. High indium content graded channel GainAs/AlinAs pseudomorphic MODFETs

    NASA Astrophysics Data System (ADS)

    Laskar, J.; Kolodzey, J.; Boor, S.; Hsieh, K. C.; Kalem, S.; Caracci, S.; Ketterson, A. A.; Brock, T.; Adesida, I.; Sivco, D.; Cho, A. Y.

    1990-03-01

    We report on the electrical and microstructural properties of InP/GaxIn 1 -xAs/Al0.48In0.52As modulation doped layers having compositionally graded active channels with different channel thicknesses. The layers were grown by solid source molecular beam epitaxy on Fe-doped InP substrates. The undoped GaInAs two dimensional electron gas channel layers were grown having indium compositions graded from x = 0.53 at the substrate buffer to x= 0.65 at the heterointerface by varying the Ga cell temperature during growth. Active channel thicknesses of 20 nm and 30 nm were compared with lattice matched layers. Transmission electron microscope image analysis indicates no misfit dislocations in these structures. Hall-effect measurements at 300 K show an increase in the mobility from 8,380 cm2/Vs for the lattice matched layer to 12,500 cm2/Vs for the 30 nm pseudomorphic layer. Small gate-length, 0.25 μn, MODFETs were fabricated to determine effective velocity values from transconductance ( g m ) and current gain ( h 21 ) measurements. The peak dc extrinsic g m increased from 367 mS/mm for the lattice matched layer to 668 mS/mm for the 30 nm pseudomorphic layer. The effective electron carrier velocity increased from 1.57 × 107 cm/s for the lattice matched layer to 1.88 × 107 cm/s for the 30 nm pseudomorphic layer. Our results show that compositional grading is a useful technique to obtain thick pseudomorphic layers with good transport properties.

  7. Use of a Shiga toxin (Stx)-enzyme-linked immunosorbent assay and immunoblot for detection and isolation of Stx-producing Escherichia coli from naturally contaminated beef.

    PubMed

    Atalla, H N; Johnson, R; McEwen, S; Usborne, R W; Gyles, C L

    2000-09-01

    The purpose of this study was to evaluate an enzyme-linked immunosorbent assay (ELISA) and an immunoblot procedure for detection and isolation of Shiga toxin-producing Escherichia coli (STEC) from beef, and to correlate the presence of STEC in beef with E. coli and total coliform counts. A total of 120 samples of boneless beef supplied to a meat processor in southern Ontario were tested for the presence of STEC, E. coli, and total coliforms. Following enrichment in modified tryptic soy broth, samples were screened for Shiga toxin (Stx) by a Stx-ELISA and a Vero cell assay (VCA). Samples that were positive in the Stx-ELISA were subjected to the Stx-immunoblot for STEC isolation. Overall, 33.3% of samples were positive in the VCA, and 34.2% were positive in the Stx-ELISA. There was almost complete agreement between the Stx-ELISA and the VCA results (kappa = 0.98). The sensitivity and specificity of the Stx-ELISA with respect to the VCA were 100% and 98.75%, respectively. STEC were isolated by the Stx-immunoblot from 87.8% of the samples that were positive in the Stx-ELISA. The STEC isolates belonged to 19 serotypes, with serotype O113:H21 accounting for 10 of 41 isolates. No STEC of serotype O157:H7 were isolated. There was a significant correlation between E. coli counts and total coliform counts (Spearman correlation coefficient = 0.68, P < 0.01). The E. coli count was positively correlated with detection of STEC by both the Stx-ELISA and the VCA (P < 0.01). PMID:10983787

  8. Fallout plume of submerged oil from Deepwater Horizon

    PubMed Central

    Valentine, David L.; Fisher, G. Burch; Bagby, Sarah C.; Nelson, Robert K.; Reddy, Christopher M.; Sylva, Sean P.; Woo, Mary A.

    2014-01-01

    The sinking of the Deepwater Horizon in the Gulf of Mexico led to uncontrolled emission of oil to the ocean, with an official government estimate of ∼5.0 million barrels released. Among the pressing uncertainties surrounding this event is the fate of ∼2 million barrels of submerged oil thought to have been trapped in deep-ocean intrusion layers at depths of ∼1,000–1,300 m. Here we use chemical distributions of hydrocarbons in >3,000 sediment samples from 534 locations to describe a footprint of oil deposited on the deep-ocean floor. Using a recalcitrant biomarker of crude oil, 17α(H),21β(H)-hopane (hopane), we have identified a 3,200-km2 region around the Macondo Well contaminated by ∼1.8 ± 1.0 × 106 g of excess hopane. Based on spatial, chemical, oceanographic, and mass balance considerations, we calculate that this contamination represents 4–31% of the oil sequestered in the deep ocean. The pattern of contamination points to deep-ocean intrusion layers as the source and is most consistent with dual modes of deposition: a “bathtub ring” formed from an oil-rich layer of water impinging laterally upon the continental slope (at a depth of ∼900–1,300 m) and a higher-flux “fallout plume” where suspended oil particles sank to underlying sediment (at a depth of ∼1,300–1,700 m). We also suggest that a significant quantity of oil was deposited on the ocean floor outside this area but so far has evaded detection because of its heterogeneous spatial distribution. PMID:25349409

  9. The effect of transdermal scopolamine for the prevention of postoperative nausea and vomiting

    PubMed Central

    Antor, María A.; Uribe, Alberto A.; Erminy-Falcon, Natali; Werner, Joseph G.; Candiotti, Keith A.; Pergolizzi, Joseph V.; Bergese, Sergio D.

    2014-01-01

    Postoperative nausea and vomiting (PONV) is one of the most common and undesirable complaints recorded in as many as 70–80% of high-risk surgical patients. The current prophylactic therapy recommendations for PONV management stated in the Society of Ambulatory Anesthesia (SAMBA) guidelines should start with monotherapy and patients at moderate to high risk, a combination of antiemetic medication should be considered. Consequently, if rescue medication is required, the antiemetic drug chosen should be from a different therapeutic class and administration mode than the drug used for prophylaxis. The guidelines restrict the use of dexamethasone, transdermal scopolamine, aprepitant, and palonosetron as rescue medication 6 h after surgery. In an effort to find a safer and reliable therapy for PONV, new drugs with antiemetic properties and minimal side effects are needed, and scopolamine may be considered an effective alternative. Scopolamine is a belladonna alkaloid, α-(hydroxymethyl) benzene acetic acid 9-methyl-3-oxa-9-azatricyclo non-7-yl ester, acting as a non-selective muscarinic antagonist and producing both peripheral antimuscarinic and central sedative, antiemetic, and amnestic effects. The empirical formula is C17H21NO4 and its structural formula is a tertiary amine L-(2)-scopolamine (tropic acid ester with scopine; MW = 303.4). Scopolamine became the first drug commercially available as a transdermal therapeutic system used for extended continuous drug delivery during 72 h. Clinical trials with transdermal scopolamine have consistently demonstrated its safety and efficacy in PONV. Thus, scopolamine is a promising candidate for the management of PONV in adults as a first line monotherapy or in combination with other drugs. In addition, transdermal scopolamine might be helpful in preventing postoperative discharge nausea and vomiting owing to its long-lasting clinical effects. PMID:24782768

  10. An isotopic biogeochemical study of the Green River oil shale.

    PubMed

    Collister, J W; Summons, R E; Lichtfouse, E; Hayes, J M

    1992-12-01

    Thirty-five different samples from three different sulfur cycles were examined in this stratigraphically oriented study of the Shell 22x-l well (U.S.G.S. C177 core) in the Piceance Basin, Colorado. Carbon isotopic compositions of constituents of Green River bitumens indicate mixing of three main components: products of primary photoautotrophs and their immediate consumers (delta approximately -30% vs PDB), products of methanotrophic bacteria (delta approximately -85%), and products of unknown bacteria (delta approximately -40%). For individual compounds synthesized by primary producers, delta-values ranged from -28 to -32%. 13C contents of individual primary products (beta-carotane, steranes, acyclic isoprenoids, tricyclic triterpenoids) were not closely correlated, suggesting diverse origins for these materials. 13C contents of numerous hopanoids were inversely related to sulfur abundance, indicating that they derived both from methanotrophs and from other bacteria, with abundances of methanotrophs depressed when sulfur was plentiful in the paleoenvironment. gamma-Cerane coeluted with 3 beta(CH3),17 alpha(H),21 beta(H)-hopane, but delta-values could be determined after deconvolution. gamma-Cerane (delta approximately -25%) probably derives from a eukaryotic heterotroph grazing on primary materials, the latter compound (delta approximately -90%) must derive from methanotrophic organisms. 13C contents of n-alkanes in bitumen differed markedly from those of paraffins generated pyrolytically. Isotopic and quantitative relationships suggest that alkanes released by pyrolysis derived from a resistant biopolymer of eukaryotic origin and that this was a dominant constituent of total organic carbon. PMID:11540064

  11. Optimisation research of petroleum hydrocarbon biodegradation in weathered drilling wastes from waste pits.

    PubMed

    Steliga, Teresa; Jakubowicz, Piotr; Kapusta, Piotr

    2010-12-01

    The aim of this article is to discuss the problem of drilling waste remediation. Analyses and research showed that material stored in waste pits could be classified as soil with a high level of petroleum impurities (total petroleum hydrocarbons [TPH] = 102,417-132,472 mg kg(-1) dry mass). While preparing the complex technology of soil decontamination (which included primary reclamation, basic bioremediation and inoculation with biopreparations based on indigenous bacteria and fungi), laboratory tests indicated the use of an ex-situ method was fundamental. Remediation was controlled with a chromatographic method of qualitative and quantitative determination of petroleum hydrocarbons. Based on analytical data, there was the possibility to determine the effectiveness of consecutive purifying phases. Laboratory tests, following 135 days of basic bioremediation stimulated by optimum conditions to activate the growth of indigenous micro-organisms, resulted in a decrease in the TPH content, which was in the range of 52.3-72.5%. The next phase of soil decontamination lasted 135 days and involved the use of inoculation with biopreparations based on indigenous micro-organisms and fungi. This process enabled a TPH decrease of 93.8- 94.3%. Laboratory biodegradation research was done with the use of the biomarker C30-17α(H)21β(H)-hopane to normalize analyte (TPH, Σn-C8-n-C22 and Σn-C23-n-C36) concentrations. The calculated first-order biodegradation constants enable estimation of the purification stage dynamics and the effectiveness of the applied biopreparations. Furthermore, they represent the biodegradation degree of individual n-alkanes in subsequent stages of the soil purification process. PMID:20022901

  12. Early Attachment Sites for Shiga-Toxigenic Escherichia coli O157:H7 in Experimentally Inoculated Weaned Calves▿

    PubMed Central

    Dean-Nystrom, Evelyn A.; Stoffregen, William C.; Bosworth, Brad T.; Moon, Harley W.; Pohlenz, Joachim F.

    2008-01-01

    Weaned 3- to 4-month-old calves were fasted for 48 h, inoculated with 1010 CFU of Shiga toxin-positive Escherichia coli (STEC) O157:H7 strain 86-24 (STEC O157) or STEC O91:H21 strain B2F1 (STEC O91), Shiga toxin-negative E. coli O157:H7 strain 87-23 (Stx− O157), or a nonpathogenic control E. coli strain, necropsied 4 days postinoculation, and examined bacteriologically and histologically. Some calves were treated with dexamethasone (DEX) for 5 days (3 days before, on the day of, and 1 day after inoculation). STEC O157 bacteria were recovered from feces, intestines, or gall bladders of 74% (40/55) of calves 4 days after they were inoculated with STEC O157. Colon and cecum were sites from which inoculum-type bacteria were most often recovered. Histologic lesions of attaching-and-effacing (A/E) O157+ bacteria were observed in 69% (38/55) of the STEC O157-inoculated calves. Rectum, ileocecal valve, and distal colon were sites most likely to contain A/E O157+ bacteria. Fecal and intestinal levels of STEC O157 bacteria were significantly higher and A/E O157+ bacteria were more common in DEX-treated calves than in nontreated calves inoculated with STEC O157. Fecal STEC O157 levels were significantly higher than Stx− O157, STEC O91, or control E. coli; only STEC O157 cells were recovered from tissues. Identifying the rectum, ileocecal valve, and distal colon as early STEC O157 colonization sites and finding that DEX treatment enhances the susceptibility of weaned calves to STEC O157 colonization will facilitate the identification and evaluation of interventions aimed at reducing STEC O157 infection in cattle. PMID:18723644

  13. Exercise and improved insulin sensitivity in older women: evidence of the enduring benefits of higher intensity training.

    PubMed

    DiPietro, Loretta; Dziura, James; Yeckel, Catherine W; Neufer, P Darrell

    2006-01-01

    Few studies have compared the relative benefits of moderate- vs. higher intensity exercise training on improving insulin sensitivity in older people while holding exercise volume constant. Healthy older (73 +/- 10 yr) women (N = 25) who were inactive, but not obese, were randomized into one of three training programs (9-mo duration): 1) high-intensity [80% peak aerobic capacity (V(O2)peak); T(H)] aerobic training; 2) moderate-intensity (65% V(O2)peak; T(M)) aerobic training; or 3) low-intensity (stretching) placebo control (50% V(O2)peak); C(TB)). Importantly, exercise volume (300 kcal/session) was held constant for subjects in both the T(H) and the T(M) groups. V(O2)peak was determined by using a graded exercise challenge on a treadmill. Total body fat and lean mass were determined with dual-energy X-ray absorptiometry. The rate of insulin-stimulated glucose utilization as well as the suppression of lipolysis were determined approximately 72 h after the final exercise bout by using a two-step euglycemic-hyperinsulinemic clamp. We observed improved glucose utilization at the higher insulin dose with training, but these improvements were statistically significant only in the T(H) (21%; P = 0.02) compared with the T(M) (16%; P = 0.17) and C(TB) (8%; P = 0.37) groups and were observed without changes in either body composition or V(O2)peak. Likewise in the T(H) group, we detected a significant improvement in insulin-stimulated suppression (%) of adipose tissue lipolysis at the low-insulin dose (38-55%, P < 0.05). Our findings suggest that long-term higher intensity exercise training provides more enduring benefits to insulin action compared with moderate- or low-intensity exercise, likely due to greater transient effects.

  14. Fine Particulate Matter Components and Emergency Department Visits for Cardiovascular and Respiratory Diseases in the St. Louis, Missouri–Illinois, Metropolitan Area

    PubMed Central

    Winquist, Andrea; Schauer, James J.; Turner, Jay R.

    2015-01-01

    Background: Given that fine particulate matter (≤ 2.5 μm; PM2.5) is a mixture of multiple components, it has been of high interest to identify its specific health-relevant physical and/or chemical features. Objectives: We conducted a time-series study of PM2.5 and cardiorespiratory emergency department (ED) visits in the St. Louis, Missouri–Illinois metropolitan area, using 2 years of daily PM2.5 and PM2.5 component measurements (including ions, carbon, particle-phase organic compounds, and elements) made at the St. Louis-Midwest Supersite, a monitoring site of the U.S. Environmental Protection Agency Supersites ambient air monitoring research program. Methods: Using Poisson generalized linear models, we assessed short-term associations between daily cardiorespiratory ED visit counts and daily levels of 24 selected pollutants. Associations were estimated for interquartile range changes in each pollutant. To allow comparison of relationships among multiple pollutants and outcomes with potentially different lag structures, we used 3-day unconstrained distributed lag models controlling for time trends and meteorology. Results: Considering results of our primary models, as well as sensitivity analyses and models assessing co-pollutant confounding, we observed robust associations of cardiovascular disease visits with 17α(H),21β(H)-hopane and congestive heart failure visits with elemental carbon. We also observed a robust association of respiratory disease visits with ozone. For asthma/wheeze, associations were strongest with ozone and nitrogen dioxide; observed associations of asthma/wheeze with PM2.5 and its components were attenuated in two-pollutant models with these gases. Differential measurement error due to differential patterns of spatiotemporal variability may have influenced patterns of observed associations across pollutants. Conclusions: Our findings add to the growing field examining the health effects of PM2.5 components. Combustion

  15. The Efficacy of a Chinstrap in Treating Sleep Disordered Breathing and Snoring

    PubMed Central

    Bhat, Sushanth; Gushway-Henry, Neola; Polos, Peter G.; DeBari, Vincent A.; Riar, Sandeep; Gupta, Divya; Lysenko, Liudmila; Patel, Disha; Pi, Justin; Chokroverty, Sudhansu

    2014-01-01

    Study Objectives: A previously published case report suggested that a chinstrap alone might improve obstructive sleep apnea (OSA). We conducted this study to determine whether a chinstrap was a feasible alternative to continuous positive airway pressure (CPAP) in patients with OSA. Methods: 26 adult patients with OSA (apnea-hypopnea index [AHI] > 5/h on diagnostic polysomnogram [PSG]) underwent a modified split-night PSG, using only a chinstrap for the first 2 hours of sleep, followed by CPAP titration for the remainder of the night. Improvements in AHI, arterial oxygen saturation (SpO2), and snoring with chinstrap use were compared to results with optimal CPAP pressures. Results: There was no significant difference between the diagnostic PSG and the chinstrap portion of the split-night PSG in the following parameters: general AHI (median [IQR] 16.0/h [9.7-26.0] vs. 25.9/h [10.7-42.7]), SpO2 nadir (84.0% [80.5-87.5] vs. 87.0 [84.0-88.5]), AHI in REM sleep (26.7/h [16.8-43.7] vs. 42.4/h [21.3-57.7]), AHI in supine sleep (24.9/h [11.9-51.5] vs. 29.8/h [11.7-55.5]), snoring index (253.2/h [147.5-353.1] vs. 180.0/h [9.8-393.3]) or subjective snoring scale (3.0 [0.8-3.0] vs. 2.5 [0.4-3.0]). The AHI and SpO2 nadir in the 13 patients with mild OSA also did not improve with chinstrap use (9.6/h [8.1-12.2] vs. 10.6/h [6.8-35.4] and 87.0% [83.0-90.0] vs. 88.0% [87.0-89.0]). All these parameters showed significant improvement with optimal CPAP titration (p < 0.05). Conclusions: A chinstrap alone is not an effective treatment for OSA. It does not improve sleep disordered breathing, even in mild OSA, nor does it improve the AHI in REM sleep or supine sleep. It is also ineffective in improving snoring. Citation: Bhat S, Gushway-Henry N, Polos PG, DeBari VA, Riar S, Gupta D, Lysenko L, Patel D, Pi J, Chokroverty S. The efficacy of a chinstrap in treating sleep disordered breathing and snoring. J Clin Sleep Med 2014;10(8):887-892. PMID:25126035

  16. Crystal structures of five new substituted tetrahydro-1-benzazepines with potential antiparasitic activity.

    PubMed

    Macías, Mario A; Acosta, Lina M; Sanabria, Carlos M; Palma, Alirio; Roussel, Pascal; Gauthier, Gilles H; Suescun, Leopoldo

    2016-05-01

    Tetrahydro-1-benzazepines have been described as potential antiparasitic drugs for the treatment of chagas disease and leishmaniasis, two of the most important so-called `forgotten tropical diseases' affecting South and Central America, caused by Trypanosoma cruzi and Leishmania chagasi parasites, respectively. Continuing our extensive work describing the structural characteristics of some related compounds with interesting biological properties, the crystallographic features of three epoxy-1-benzazepines, namely (2SR,4RS)-6,8-dimethyl-2-(naphthalen-1-yl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, (1), (2SR,4RS)-6,9-dimethyl-2-(naphthalen-1-yl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, (2), and (2SR,4RS)-8,9-dimethyl-2-(naphthalen-1-yl)-2,3,4,5-tetrahydro-1H-1,4-epoxy-1-benzazepine, (3), all C22H21NO, and two 1-benzazepin-4-ols, namely 7-fluoro-cis-2-[(E)-styryl]-2,3,4,5-tetrahydro-1H-1-benzazepin-4-ol, C18H18FNO, (4), and 7-fluoro-cis-2-[(E)-pent-1-enyl]-2,3,4,5-tetrahydro-1H-1-benzazepin-4-ol, C15H20FNO, (5), are described. Some peculiarities in the crystallization behaviour were found, involving significant variations in the crystalline structures as a result of modest changes in the peripheral substituents in (1)-(3) and the occurrence of discrete disorder due to the molecular overlay of enantiomers with more than one conformation in (5). In particular, an interesting phase change on cooling was observed for compound (5), accompanied by an approximate fourfold increase of the unit-cell volume and a change of the Z' value from 1 to 4. This transition is a consequence of the partial ordering of the pentenyl chains in half of the molecules breaking half of the -3 symmetry axes observed in the room-temperature structure of (5). The structural assembly in all the title compounds is characterized by not only (N,O)-H...(O,N) hydrogen bonds, but also by unconventional C-H...O contacts, resulting in a wide diversity of packing. PMID:27146563

  17. Crystal structures of two substituted thia­zolidine derivatives

    PubMed Central

    Viswanathan, Vijayan; Rao, Naga Siva; Raghunathan, Raghavachary; Velmurugan, Devadasan

    2016-01-01

    In the first of the compounds reported herein, namely 6′-ferrocenyl-6a′-nitro-6′,6a′,6b′,7′,9′,11a′-hexa­hydro-2H-spiro­[ace­naphthyl­ene-1,11′-chromeno[3′,4′:3,4]pyrrolo­[1,2-c]thia­zol]-2-one, [Fe(C5H5)(C29H21N2O4S)], (I), the thia­zolidine ring adopts a twist conformation on the methine N—C atoms. In the second compound, viz. 6′-(4-methoxy­phen­yl)-6a′-nitro-6′,6a′,6b′,7′,9′,11a′-hexa­hydro-2H-spiro­[ace­naphthyl­ene-1,11′-chromeno[3′,4′:3,4]pyrrolo­[1,2-c]thia­zol]-2-one, [Fe(C5H5)(C26H19N2O5S)], (II), the thia­zolidine ring adopts an envelope conformation with a methine C atom as the flap. In both compounds, the pyrrolidine ring adopts a twist conformation on the thia­zolidine and tetra­hydro­pyran C atoms. The mean planes of the thia­zolidine and pyrrolidine rings subtend angles of 67.30 (1) and 62.95 (7)° in (I) and (II), respectively, while the mean plane of the pyrrolidine ring makes dihedral angles of 76.53 (1) and 87.74 (7)° with the ace­naphthyl­ene ring system in (I) and (II), respectively. In both compounds, an intra­molecular C—H⋯O hydrogen bond forms an S(7) ring motif. In the crystal of (I), mol­ecules are linked via two different C—H⋯O hydrogen bonds, forming chains along [001] and [100]. In (II), they are linked through C—H⋯O hydrogen bonds, forming dimers with an R 2 2(10) ring motif while C—H⋯π inter­actions link the mol­ecules in a head-to-tail fashion, forming chains along the a-axis direction. PMID:27536396

  18. From Farm to Table: Follow-Up of Shiga Toxin-Producing Escherichia coli Throughout the Pork Production Chain in Argentina.

    PubMed

    Colello, Rocío; Cáceres, María E; Ruiz, María J; Sanz, Marcelo; Etcheverría, Analía I; Padola, Nora L

    2016-01-01

    Pigs are important reservoirs of Shiga toxin-producing Escherichia coli (STEC). The entrance of these strains into the food chain implies a risk to consumers because of the severity of hemolytic uremic syndrome. This study reports the prevalence and characterization of STEC throughout the pork production chain. From 764 samples, 31 (4.05%) were stx positive by PCR screening. At farms, 2.86% of samples were stx positive; at slaughter, 4.08% of carcasses were stx positive and at boning rooms, 6% of samples were stx positive. These percentages decreased in pork meat ready for sale at sales markets (4.59%). From positive samples, 50 isolates could be characterized. At farms 37.5% of the isolates carried stx1/stx2 genes, 37.5% possessed stx2e and 25%, carried only stx2. At slaughter we detected 50% of isolates positive for stx2, 33% for stx2e, and 16% for stx1/stx2. At boning rooms 59% of the isolates carried stx1/stx2, 14% stx2e, and 5% stx1/stx2/stx2e. At retail markets 66% of isolates were positive for stx2, 17% stx2e, and 17% stx1/stx2. For the other virulence factors, ehxA and saa were not detected and eae gene was detected in 12% of the isolates. Concerning putative adhesins, agn43 was detected in 72%, ehaA in 26%, aida in 8%, and iha in 6% of isolates. The strains were typed into 14 E. coli O groups (O1, O2, O8, O15, O20, O35, O69, O78, O91, O121, O138, O142, O157, O180) and 10 H groups (H9, H10, H16, H21, H26, H29, H30, H32, H45, H46). This study reports the prevalence and characterization of STEC strains through the chain pork suggesting the vertical transmission. STEC contamination originates in the farms and is transferred from pigs to carcasses in the slaughter process and increase in meat pork at boning rooms and sales markets. These results highlight the need to implement an integrated STEC control system based on good management practices on the farm and critical control point systems in the food chain. PMID:26903972

  19. Deep Imaging Observations of the Lupus 3 Cloud: Dark Cloud Revealed as Infrared Reflection Nebula

    NASA Astrophysics Data System (ADS)

    Nakajima, Yasushi; Nagata, Tetsuya; Sato, Shuji; Nagayama, Takahiro; Nagashima, Chie; Kato, Daisuke; Kurita, Mikio; Kawai, Toshihide; Tamura, Motohide; Nakaya, Hidehiko; Sugitani, Koji

    2003-03-01

    We carried out deep imaging observations of the Lupus 3 dark cloud in near-infrared J, H, and Ks bands. An area of ~8'×8' was observed, which corresponds to a projected area of ~0.4×0.4 pc at the distance of the cloud, ~150 pc. Lupus 3 showed itself as a near-infrared nebula that has a surface brightness higher than the adjacent sky at all the three wavelengths. In a JHKs color composite image (blue, green, and red are assigned to J, H, and Ks, respectively), three dark red cores are surrounded by a blue halo. The surface brightness was measured with 5 σ limiting magnitudes of J=21.6, H=21.3, and Ks=20.6 mag arcsec-2. The appearance of the nebula depends on the wavelength. In the J band, dark cores are surrounded by a brighter halo, while in the Ks band, the dark cores of the J band are bright except for the central part of two of the cores. The appearance in the H band is intermediate between those of the J and Ks bands, having dark cores surrounded by local maxima of the surface brightness and decreased surface brightness farther out. The surface brightness is J=20.6, H=19.8, and Ks=19.4 mag arcsec-2 at the maximum in each band. Photometry of the point sources was done with 10 σ limiting magnitudes of J=20.1, H=18.8, and Ks=17.7. We constructed an extinction map of the background stars, using the H-K color of 1974 sources and the standard reddening law of Rieke & Lebofsky. The maximum value for the extinction is AV=47 mag. There are three local maxima of the extinction with AV>~30 mag, which we consider to be dense cores. Their positions agree with the cores identified with the surface brightness appearance. The surface brightness and its relationship with the extinction are understood in terms of scattering of starlight by dust. The values of the maximum surface brightness can be explained by scattering of starlight by dust in the cloud if we adopt a model of grain size distribution by Weingartner & Draine.

  20. Pulsating Mantle Hypothesis "PMH" and its Applications on Apparent Solar Day Length Variations, Geodynamo and Plate Tectonics Theories, Tide, Earth's Axis Tilted and Earthquake Forecasting

    NASA Astrophysics Data System (ADS)

    Gholibeigian, H.; Amirshakarami, A.

    2012-12-01

    In this hypothesis, two phenomena; Inner Core Dislocation (ICD) and Outer Core Bulge (OCB) have appeared inside the Earth due to unbalanced gravitational attraction of the Sun and the Moon, and consequently the mantle is under diurnal cyclic pulsating load by it. In the other words, the inner core's center and axis (Earth's magnetic axis) do not crossed or overlapped on the Earth's center and axis (geographic axis) and distance between these two centers vary permanently in magnitude and direction. See Fig 1,2. ( C is geo-center, C' is inner core's center and always CC'>>0 ). These two phenomena which have diurnal, monthly and yearly cycles, have generated hydro-magneto-thermo-mechanical load including high kinetic energy which produces forced convection system in the outer core and pressurizes the mantle from its bottom. In this paper, we briefly discuss the six scientific results and applications of the hypothesis which are derived from ICD&OCB 1- Cause of apparent solar day length variations, and its overlapping with ICD&OCB variations spectrum, Fig 2, as the first observable factor for proving the PMH. In this section we use data for apparent solar day length variations in year 1998, and Figure's sheet is the same equatorial sheet, minimum of length day is in September 16 which is 24h-21.3 sec., as we can see the length of the ICD&OCB's vector which is result of the Sun and Moon's gravity forces, is minimum but in Dec. 22 which length day is 24h+29 sec, its vector is bigger 2- Generation and diurnal variation of the Earth's magnetic field and its overlapping with ICD&OCB variation as the second observable factor for proving the PMH. In this section we develop the Geodynamo Theory. 3- The ICD&OCB as the main engine of the tectonic plate's motion is discussed. In this section we develop the Plate Tectonics Theory. 4- How four Earth's systems; ICD&OCB, Sun's thermal energy, Sun and Moon's gravity forces interact and work together for generation of tide. 5- Eight

  1. Crowd-sourcing Near-Earth Asteroid Science with the OSIRIS-REx Target Asteroids! Program

    NASA Astrophysics Data System (ADS)

    Hergenrother, Carl W.; Hill, Dolores H.; Spitz, Anna; Barucci, Maria Antonietta; Binzel, Richard P.; Beshore, Ed; Bottke, William; Brucato, John Robert; Clark, Beth E.; Cloutis, Edward; Connolly, Harold C.; Delbo, Marco; Dotto, Elisabetta; Ieva, Simone; Licandro, Javier; Nolan, Michael C.; Perna, Davide; Sandford, Scott A.; Takir, Driss; Lauretta, Dante S.

    2014-11-01

    OSIRIS-REx Target Asteroids! is an award-winning citizen science project conducted as part of the Communications and Public Engagement program of the NASA OSIRIS-REx asteroid sample return mission. The project furthers the study of near-Earth asteroids (NEA) and promotes interest among the amateur astronomy community. The goal of Target Asteroids! is to expand the pool of observers who can contribute to the characterization of NEAs. We also seek to coordinate the observation of specific asteroids in order to maximize the usefulness of the data and to minimize duplication of effort.Target Asteroids! was originally focused on a list of ~80 NEAs suitable for spacecraft sample return compiled by the OSIRIS-REx science team. The list was constrained to NEAs with absolute magnitude H < 21.5, perihelion distance > 0.8 AU, aphelion distance < 2.0 AU and inclination < 8°. Since many sample return targets are beyond the reach of typical amateur telescopes (limiting magnitudes of ~14 to 20), the program was expanded to include other objects, namely asteroids that shed light on the properties of OSIRIS-REx target (101955) Bennu, bright NEAs making relatively close approaches to Earth and radar target NEAs. An introductory paper on the goals and methods of Target Asteroids! was published in the Minor Planet Bulletin (Hergenrother & Hill, Minor Planet Bulletin 40, 164-166, 2013).Since 2012, over 100 participants with a wide range of instrumentation and experience from around the world have contributed photometry of 53 asteroids. While small telescope users cannot produce high S/N observations for faint objects, they do have the advantage of being able to make observations often. A large number of low S/N observations are useful if made over different observing geometries. Utilizing many photometric observations made at different times and phase angles, small telescope users can produce direct measurements of the phase function, absolute magnitude, broadband color, and rotation

  2. Crystal structures of two substituted thia-zolidine derivatives.

    PubMed

    Viswanathan, Vijayan; Rao, Naga Siva; Raghunathan, Raghavachary; Velmurugan, Devadasan

    2016-08-01

    In the first of the compounds reported herein, namely 6'-ferrocenyl-6a'-nitro-6',6a',6b',7',9',11a'-hexa-hydro-2H-spiro-[ace-naphthyl-ene-1,11'-chromeno[3',4':3,4]pyrrolo-[1,2-c]thia-zol]-2-one, [Fe(C5H5)(C29H21N2O4S)], (I), the thia-zolidine ring adopts a twist conformation on the methine N-C atoms. In the second compound, viz. 6'-(4-methoxy-phen-yl)-6a'-nitro-6',6a',6b',7',9',11a'-hexa-hydro-2H-spiro-[ace-naphthyl-ene-1,11'-chromeno[3',4':3,4]pyrrolo-[1,2-c]thia-zol]-2-one, [Fe(C5H5)(C26H19N2O5S)], (II), the thia-zolidine ring adopts an envelope conformation with a methine C atom as the flap. In both compounds, the pyrrolidine ring adopts a twist conformation on the thia-zolidine and tetra-hydro-pyran C atoms. The mean planes of the thia-zolidine and pyrrolidine rings subtend angles of 67.30 (1) and 62.95 (7)° in (I) and (II), respectively, while the mean plane of the pyrrolidine ring makes dihedral angles of 76.53 (1) and 87.74 (7)° with the ace-naphthyl-ene ring system in (I) and (II), respectively. In both compounds, an intra-molecular C-H⋯O hydrogen bond forms an S(7) ring motif. In the crystal of (I), mol-ecules are linked via two different C-H⋯O hydrogen bonds, forming chains along [001] and [100]. In (II), they are linked through C-H⋯O hydrogen bonds, forming dimers with an R 2 (2)(10) ring motif while C-H⋯π inter-actions link the mol-ecules in a head-to-tail fashion, forming chains along the a-axis direction.

  3. Alpha-adrenergic regulation of systemic peripheral resistance and blood flow distribution in the turtle Trachemys scripta during anoxic submergence at 5 degrees C and 21 degrees C.

    PubMed

    Stecyk, J A W; Overgaard, J; Farrell, A P; Wang, T

    2004-01-01

    Anoxic exposure in the anoxia-tolerant freshwater turtle is attended by substantial decreases in heart rate and blood flows, but systemic blood pressure (P(sys)) only decreases marginally due to an increase in systemic peripheral resistance (R(sys)). Here, we investigate the role of the alpha-adrenergic system in modulating R(sys) during anoxia at 5 degrees C and 21 degrees C in the turtle Trachemys scripta, and also describe how anoxia affects relative systemic blood flow distribution (%.Q(sys)) and absolute tissue blood flows. Turtles were instrumented with an arterial cannula for measurement of P(sys) and ultrasonic flow probes on major systemic blood vessels for determination of systemic cardiac output ((.Qsys)). Alpha-adrenergic tone was assessed from vascular injections of alpha-adrenergic agonists and antagonists (phenylephrine and phentolamine, respectively) during normoxia and following either 6 h (21 degrees C) or 12 days (5 degrees C) of anoxic submergence. Coloured microspheres, injected through a left atrial cannula during normoxia and anoxia, as well as after alpha-adrenergic stimulation and blockade during anoxia at both temperatures, were used to determine relative and absolute tissue blood flows. Anoxia was associated with an increased R(sys) and functional alpha-adrenergic vasoactivity at both acclimation temperatures. However, while anoxia at 21 degrees C was associated with a high systemic alpha-adrenergic tone, the progressive increase of R(sys) at 5 degrees C was not mediated by alpha-adrenergic control. A redistribution of blood flow away from ancillary vascular beds towards more vital circulations occurred with anoxia at both acclimation temperatures. %.Q(sys) and absolute blood flow were reduced to the digestive and urogenital tissues (approximately 2- to 15-fold), while %.Q(sys) and absolute blood flows to the heart and brain were maintained at normoxic levels. The importance of liver and muscle glycogen stores in fueling anaerobic

  4. Role of exposure/recovery schedule in micronuclei induction by several promutagens in V79-derived cells expressing human CYP2E1 and SULT1A1.

    PubMed

    Jia, Hansi; Zhang, Chiteng; Glatt, Hansruedi; Liu, Yungang

    2016-09-15

    The standard procedure for the micronucleus test in cell lines requires a short exposure (≤0.5 cell cycle) to the test compounds followed by a long recovery (≥1.5 cell cycle), and in case of negative or equivocal results, a second test with extended exposure (≥2 cell cycles) without or with a recovery time. In general the two procedures are advantageous for detecting clastogens and aneugens, respectively. However, whether the recommended procedures apply to micronucleus tests with promutagens in cell lines genetically engineered for expressing biotransformation enzymes has not been identified. In this study, several promutagens dependent on cytochrome P450 (CYP) 2E1 and/or sulfotransferase (SULT) 1A1 were used in the micronucleus test in a Chinese hamster V79-derived cell line expressing human CYP2E1 and SULT1A1 (V79-hCYP2E1-hSULT1A1), with varying exposure/recovery schedules: 3h/21h, 6h/18h, 12h/12h, 18h/6h, and 24h/0h, in comparison with known clastogens and aneugens in V79 control cells. The results showed peaked micronuclei induction by mitomycin C and bleomycin (clastogens) at the 12h/12h schedule, while colchicine and vinblastine (aneugens) showed the strongest effect at 24h/0h. Catechol and trihydroxybenzene (activated by CYP2E1) induced micronuclei most strongly at 6h/18h, whereas somewhat longer exposures were optimal for hydroquinone, another compound activated by CYP2E1. 1-Hydroxymethylpyrene (activated by SULT1A1) and 1-methylpyrene (activated sequentially by CYP2E1 and SULT1A1) produced the highest response with the 18h/6h treatment regimen. Moreover, mitotic arrest by 1-hydroxymethylpyrene was observed in V79-hCYP2E1-hSULT1A1 cells but not in V79 cells, and 1-methylpyrene arrested mitosis in V79-hCYP2E1-hSULT1A1 more strongly than in V79 cells. Our study suggests that intracellular bioactivation of promutagens may not delay the induction of micronuclei in the present model, and 1-methylpyrene and 1-hydroxymethylpyrene may be activated to mitosis

  5. Arresting initiation of hepatitis C virus RNA synthesis using heterocyclic derivatives.

    PubMed

    Gu, Baohua; Johnston, Victor K; Gutshall, Lester L; Nguyen, Tammy T; Gontarek, Richard R; Darcy, Michael G; Tedesco, Rosanna; Dhanak, Dashyant; Duffy, Kevin J; Kao, C Cheng; Sarisky, Robert T

    2003-05-01

    The hepatitis C virus (HCV) NS5B protein encodes an RNA-dependent RNA polymerase (RdRp), the primary catalytic enzyme of the HCV replicase complex. Recently, two benzo-1,2,4-thiadiazine compounds were shown to be potent, highly specific inhibitors of the genotype 1b HCV RdRp containing a carboxyl-terminal 21 residue truncation (delta21 HCV RdRp) (Dhanak, D., Duffy, K., Johnston, V. K., Lin-Goerke, J., Darcy, M., Shaw, A. N. G. B., Silverman, C., Gates, A. T., Earnshaw, D. L., Casper, D. J., Kaura, A., Baker, A., Greenwood, C., Gutshall, L. L., Maley, D., DelVecchio, A., Macarron, R., Hofmann, G. A., Alnoah, Z., Cheng, H.-Y., Chan, G., Khandekar, S., Keenan, R. M., and Sarisky, R. T. (2002) J. Biol. Chem. 277, 38322-38327). Compound 4 (C(21)H(21)N(3)O(4)S) reduces viral replication by virtue of its direct interaction with the viral polymerase rather than by nonspecific titration of nucleic acid template. In this study, we present several lines of evidence to demonstrate that this inhibitor interferes with the initiation step of RNA synthesis rather than acting as an elongation inhibitor. Inhibition of initial phosphodiester bond formation occurred regardless of whether replication was initiated by primer-dependent or de novo mechanisms. Filter binding studies using increasing concentrations of compound 4 did not interfere with the ability of delta21 HCV RdRp to interact with nucleic acid. Furthermore, varying the order of reagent addition in the primer extension assay showed no distinct differences in inhibition profile. Finally, surface plasmon resonance analyses provided evidence that a ternary complex is capable of forming between the RNA template, RdRp, and compound 4. Together, these data suggest that this heterocyclic agent interacts with the apoenzyme, as well as with the RNA-bound form of delta21 HCV RdRp, and therefore does not directly interfere with the RdRp-RNA interaction to mediate inhibition.

  6. Comparative chlorine and temperature tolerance of the oyster Crassostrea madrasensis: implications for cooling system fouling.

    PubMed

    Rajagopal, S; Venugopalan, V P; van der Velde, G; Jenner, H A

    2003-04-01

    Crassostrea madrasensis is an important fouling oyster in tropical industrial cooling water systems. C. madrasensis individuals attach to surfaces by cementing one of their two valves to the substratum. Therefore, oyster fouling creates more problems than mussel fouling in the cooling conduits of power stations, because unlike the latter, the shell of the former remains attached to the substratum even after the death of the animal. However, there are no published reports on the tolerance of this species to chlorination and heat treatment. The mortality pattern and physiological behaviour (oxygen consumption and filtration rate) of three size groups (13 mm, 44 mm and 64 mm mean shell length) of C. madrasensis were studied at different residual chlorine concentrations (0.25, 0.5, 0.75, 1, 2, 3 to 5 mg 1-1) and temperatures (30 degrees C to 45 degrees C). The effect of shell size (= age) on C. madrasensis mortality in the presence of chlorine and taking into account temperature was significant, with the largest size group oysters showing highest resistance. At 1 mg l-1 residual chlorine, the 13 mm and 64 mm size group oysters, took 504 h (21 d) and 744 h (31 d), respectively to reach 100% mortality. At 39 degrees C, the 13 mm size group oysters took 218 min to reach 100% mortality, whereas the 64 mm size group oysters took 325 min. The oxygen consumption and filtration rate of C. madrasensis showed progressive reduction with increasing residual chlorine concentrations. However, the filtration rate and oxygen consumption responses of C. madrasensis were not significantly different between 30 degrees C (control) and 37.5 degrees C. There was a sharp decrease in the filtration rate and oxygen consumption at 38.5 degrees C. A comparison of the present mortality data with previous reports on other bivalves suggests that the chlorine tolerance of C. madrasensis lies in between that of Perna viridis and Perna perna, while its temperature tolerance is significantly higher

  7. [μ(2)-Bis(diphenyl-phosphanyl)methane][μ(3)-bis-(diphenyl-phosphanyl)meth-yl]trichlorido-tetra-gold(I) tetra-hydro-furan disolvate.

    PubMed

    Wang, Huan-Huan; Gao, Qian; Cui, Yue; Wang, Lin; Xie, Ya-Bo

    2011-01-08

    The title tetra-nuclear complex, [Au(4)(C(25)H(21)P(2))Cl(3)(C(25)H(22)P(2))]·2C(4)H(8)O, features two non-equivalent Ph(2)PCPPh(2) fragments, one of which represents the 'complete' mol-ecule (with two H atoms at the central C atom); each of the two P atoms of this mol-ecule is coordinated by an Au atom [Au-P = 2.2256 (13) and 2.2710 (13) Å], and these two Au atoms form an Au-Au bond [3.2945 (3) Å], thus closing the five-membered Au(2)P(2)C ring. The first of these Au atoms has a terminal chlorido ligand [Au-Cl = 2.2806 (12) Å], whereas the second Au atom forms a covalent bond with the central C atom of the bis-(diphenyl-phosphino)methyl group [Au-C = 2.114 (5) Å]; the latter group in turn coordinates with its P atoms the gold atoms of the Cl-Au-Au-Cl group [Au-P = 2.2356 (13) and 2.2338 (13), Au-Au = 3.3177 (3), Au-Cl = 2.3091 (12) and 2.2950 (13) Å], thus closing the second Au(2)P(2)C ring. The two such rings have different chemical functions, but both exhibit envelope conformations. However, the first (with different substituents at the Au atoms) is non-symmetrical with one of the P atoms in the flap position of the envelope; the other one has a conformation with mirror symmetry, and the gold-substituted C atom is displaced by 0.740 (5) Å from the almost exactly planar (r.m.s. deviation = 0.0038 Å) Au(2)P(2) group.

  8. Paleogene biomarker records from the central Arctic Ocean (Integrated Ocean Drilling Program Expedition 302): Organic carbon sources, anoxia, and sea surface temperature

    NASA Astrophysics Data System (ADS)

    Weller, Petra; Stein, Ruediger

    2008-03-01

    During Integrated Ocean Drilling Program Expedition 302 (Arctic Coring Expedition (ACEX)) a more than 200 m thick sequence of Paleogene organic carbon (OC)-rich (black shale type) sediments was drilled. Here we present new biomarker data determined in ACEX sediment samples to decipher processes controlling OC accumulation and their paleoenvironmental significance during periods of Paleogene global warmth and proposed increased freshwater discharge in the early Cenozoic. Specific source-related biomarkers including n-alkanes, fatty acids, isoprenoids, carotenoids, hopanes/hopenes, hopanoic acids, aromatic terpenoids, and long-chain alkenones show a high variability of components, derived from marine and terrestrial origin. The distribution of hopanoic acid isomers is dominated by compounds with the biological 17β(H), 21β(H) configuration indicating a low level of maturity. On the basis of the biomarker data the terrestrial OC supply was significantly enriched during the late Paleocene and part of the earliest Eocene, whereas increased aquatic contributions and euxinic conditions of variable intensity were determined for the Paleocene-Eocene thermal maximum and Eocene thermal maximum 2 events as well as the middle Eocene time interval. Furthermore, samples from the middle Eocene are characterized by the occurrence of long-chain alkenones, high proportions of lycopane, and high ratios (>0.6) of (n-C35 + lycopane)/n-C31. The occurrence of C37-alkenenones, which were first determined toward the end of the Azolla freshwater event, indicates that the OC becomes more marine in origin during the middle Eocene. Preliminary U37K'-based sea surface temperature (SST) values display a long-term temperature decrease of about 15°C during the time interval 49-44.5 Ma (25° to 10°C), coinciding with the global benthic δ18O cooling trend after the early Eocene climatic optimum. At about 46 Ma, parallel with onset of ice-rafted debris, SST (interpreted as summer temperatures

  9. Extracting nuclear sizes of medium to heavy nuclei from total reaction cross sections

    NASA Astrophysics Data System (ADS)

    Horiuchi, W.; Hatakeyama, S.; Ebata, S.; Suzuki, Y.

    2016-04-01

    Background: Proton and neutron radii are fundamental quantities of atomic nuclei. To study the sizes of short-lived unstable nuclei, there is a need for an alternative to electron scattering. Purpose: The recent paper by Horiuchi et al. [Phys. Rev. C 89, 011601(R) (2014)], 10.1103/PhysRevC.89.011601 proposed a possible way of extracting the matter and neutron-skin thickness of light- to medium-mass nuclei using total reaction cross section, σR. The analysis is extended to medium to heavy nuclei up to lead isotopes with due attention to Coulomb breakup contributions as well as density distributions improved by paring correlation. Methods: We formulate a quantitative calculation of σR based on the Glauber model including the Coulomb breakup. To substantiate the treatment of the Coulomb breakup, we also evaluate the Coulomb breakup cross section due to the electric dipole field in a canonical-basis-time-dependent-Hartree-Fock-Bogoliubov theory in the three-dimensional coordinate space. Results: We analyze σR's of 103 nuclei with Z =20 , 28, 40, 50, 70, and 82 incident on light targets, H,21, 4He, and 12C. Three kinds of Skyrme interactions are tested to generate those wave functions. To discuss possible uncertainty due to the Coulomb breakup, we examine its dependence on the target, the incident energy, and the Skyrme interaction. The proton is a most promising target for extracting the nuclear sizes as the Coulomb excitation can safely be neglected. We find that the so-called reaction radius, aR=√{σR/π } , for the proton target is very well approximated by a linear function of two variables, the matter radius and the skin thickness, in which three constants depend only on the incident energy. We quantify the accuracy of σR measurements needed to extract the nuclear sizes. Conclusions: The proton is the best target because, once the incident energy is set, its aR is very accurately determined by only the matter radius and neutron-skin thickness. If σR's at

  10. Asteroid 2013 ND15: Trojan companion to Venus, PHA to the Earth

    NASA Astrophysics Data System (ADS)

    de la Fuente Marcos, C.; de la Fuente Marcos, R.

    2014-04-01

    Venus has three known co-orbitals: (322756) 2001 CK32, 2002 VE68 and 2012 XE133. The first two have absolute magnitudes 18 < H < 21. The third one, significantly smaller at H = 23.4 mag, is a recent discovery that signals the probable presence of many other similar objects: small transient companions to Venus that are also potentially hazardous asteroids (PHAs). Here, we study the dynamical evolution of the recently discovered asteroid 2013 ND15. At H = 24.1 mag, this minor body is yet another small Venus co-orbital and PHA, currently close to the Lagrangian point L4 and following the most eccentric path found so far for objects in this group. This transient Trojan will leave the 1:1 mean motion resonance within a few hundred years although it could be a recurrent librator. Due to its high eccentricity (0.6), its dynamics is different from that of the other three known Venus co-orbitals even if they all are near-Earth objects (NEOs). A Monte Carlo simulation that uses the orbital data and discovery circumstances of the four objects as proxies to estimate the current size of this population, indicates that the number of high-eccentricity, low-inclination Venus co-orbital NEOs may have been greatly underestimated by current models. Three out of four known objects were discovered with solar elongation at perigee greater than 135° even if visibility estimates show that less than 4 per cent of these objects are expected to reach perigee at such large elongations. Our calculations suggest that the number of minor bodies with sizes above 150 m currently engaged in co-orbital motion with Venus could be at least one order of magnitude larger than usually thought; the number of smaller bodies could easily be in many thousands. These figures have strong implications on the fraction of existing PHAs that can barely be detected by current surveys. Nearly 70 per cent of the objects discussed here have elongation at perigee <90° and 65 per cent are prospective PHAs.

  11. Effective interactions between nanoparticles: Creating temperature-independent solvation environments for self-assembly

    NASA Astrophysics Data System (ADS)

    Yadav, Hari O. S.; Shrivastav, Gourav; Agarwal, Manish; Chakravarty, Charusita

    2016-06-01

    The extent to which solvent-mediated effective interactions between nanoparticles can be predicted based on structure and associated thermodynamic estimators for bulk solvents and for solvation of single and pairs of nanoparticles is studied here. As a test of the approach, we analyse the strategy for creating temperature-independent solvent environments using a series of homologous chain fluids as solvents, as suggested by an experimental paper [M. I. Bodnarchuk et al., J. Am. Chem. Soc. 132, 11967 (2010)]. Our conclusions are based on molecular dynamics simulations of Au140(SC10H21)62 nanoparticles in n-alkane solvents, specifically hexane, octane, decane and dodecane, using the TraPPE-UA potential to model the alkanes and alkylthiols. The 140-atom gold core of the nanocrystal is held rigid in a truncated octahedral geometry and the gold-thiolate interaction is modeled using a Morse potential. The experimental observation was that the structural and rheological properties of n-alkane solvents are constant over a temperature range determined by equivalent solvent vapour pressures. We show that this is a consequence of the fact that long chain alkane liquids behave to a good approximation as simple liquids formed by packing of monomeric methyl/methylene units. Over the corresponding temperature range (233-361 K), the solvation environment is approximately constant at the single and pair nanoparticle levels under good solvent conditions. However, quantitative variations of the order of 10%-20% do exist in various quantities, such as molar volume of solute at infinite dilution, entropy of solvation, and onset distance for soft repulsions. In the opposite limit of a poor solvent, represented by vacuum in this study, the effective interactions between nanoparticles are no longer temperature-independent with attractive interactions increasing by up to 50% on decreasing the temperature from 361 K to 290 K, accompanied by an increase in emergent anisotropy due to

  12. Introduction to the food safety concerns of verotoxin-producing Escherichia coli.

    PubMed

    Hussein, Hussein S; Omaye, Stanley T

    2003-04-01

    Verotoxin-producing Escherichia coli (VTEC) have emerged in the past two decades as food-borne pathogens that can cause major outbreaks of human illnesses worldwide. The number of outbreaks has increased in recent years due to changes in food production and processing systems, eating habits, microbial adaptation, and methods of VTEC transmission. The human illnesses range from mild diarrhea to hemolytic uremic syndrome (HUS) that can lead to death. The VTEC outbreaks have been attributed to O157:H7 and non-O157:H7 serotypes of E. coli. These E. coli serotypes include motile (e.g., O26:H11 and O104:H21) and nonmotile (e.g., O111:H-, O145:H-, and O157:H-) strains. In the United States, E. coli O157:H7 has been the major cause of VTEC outbreaks. Worldwide, however, non-O157:H7 VTEC (e.g., members of the O26, O103, O111, O118, O145, and O166 serogroups) have caused approximately 30% of the HUS cases in the past decade. Because large numbers of the VTEC outbreaks have been attributed to consumption of ruminant products (e.g., ground beef), cattle and sheep are considered reservoirs of these food-borne pathogens. Because of the food safety concern of VTEC, a global perspective on this problem is addressed (Exp Biol Med Vol. 228, No. 4). The first objective was to evaluate the known non-O157:H7 VTEC strains and the limitations associated with their detection and characterization. The second objective was to identify the VTEC serotypes associated with outbreaks of human illnesses and to provide critical evaluation of their virulence. The third objective was to determine the rumen effect on survival of E. coli O157:H7 as a VTEC model. The fourth objective was to explore the role of intimins in promoting attaching and effacing lesions in humans. Finally, the ability of VTEC to cause persistent infections in cattle was evaluated.

  13. Time-dependent variations in milk fatty acid content of goats fed 3 different plant oils.

    PubMed

    Martínez Marín, A L; Gómez-Cortés, P; Gómez Castro, G; Juárez, M; Pérez Alba, L; Pérez Hernández, M; de la Fuente, M A

    2013-05-01

    The effect of sampling time on milk fatty acid (FA) composition after separately adding 3 plant oils to an oil-free control diet (67% cereal-soybean-based concentrate and 33% alfalfa hay) was studied in 12 Malagueña goats. Individual animals were randomly allocated to 1 of the 4 treatments: control, 48 g/d of added high oleic (OSO) or regular (RSO) sunflower oil, or linseed oil (LO). Individual milk samples were taken at 0 (covariate), 1, 12, 24, 72, 120, 192, 312, and 504 h after the beginning of the experiment. Milk FA contents (g/100g of total FA methyl esters) were analyzed in a completely randomized design with repeated measures using PROC MIXED of SAS (SAS Institute Inc., Cary, NC). Comparing results of 15 chosen FA (for example, medium-chain saturated FA trans-11 C18:1, cis-9,trans-11 C18:2, trans-10 C18:1, and C18:3n-3) indicated that throughout the duration of the experiment, feeding the control diet had little influence on the concentrations of most FA in milk. Most changes in milk FA composition due to oil supplementation had occurred within 192 h since the beginning of the experiment. However, the concentrations of 2 FA (trans-10 C18:1 in RSO and C18:3n-3 in LO treatments) continued to change until 504 h. By comparing FA values in milk fat from oil treatments with those of the control at the same sampling times, typical value differences for the 3 supplementary oils found at 504 h (21 d) were also observed at 312 h from the beginning of the experiment (13 d) and even earlier in some FA, such as medium-chain saturated FA at 120 h in RSO and LO and at 72 h in OSO, cis-9,trans-11 C18:2 and trans-10 C18:1 at 24h in RSO, trans-11 C18:1 at 12h in RSO and LO, and C18:3n-3 at 1h in LO. In the conditions assayed in these experiments, reliable results of milk FA changes were obtained at sampling times shorter than 21 d. Monitoring early changes in milk FA after the addition of plant oils to diets could help in the study of rumen and mammary metabolism of dietary

  14. Dormant Comets in the Near-Earth Asteroid Population

    NASA Astrophysics Data System (ADS)

    Mommert, Michael; Harris, Alan W.; Mueller, Michael; Hora, Joseph L.; Trilling, David E.; Knight, Matthew; Bottke, William F.; Thomas, Cristina; Delbo', Marco; Emery, Josh P.; Fazio, Giovanni; Smith, Howard A.

    2015-11-01

    The population of near-Earth objects comprises active comets and asteroids, covering a wide range of dynamical parameters and physical properties. Dormant (or extinct) comets, masquerading as asteroids, have long been suspected of supplementing the near-Earth asteroid (NEA) population. We present a search for asteroidal objects of cometary origin based on dynamical and physical considerations. Our study is based on albedos derived within the ExploreNEOs program and is extended by adding data from NEOWISE and the Akari asteroid catalog. We use a statistical approach to identify asteroids on orbits that resemble those of short-period near-Earth comets using the Tisserand parameter with respect to Jupiter, the aphelion distance, and the minimum orbital intersection distance with respect to Jupiter. We identify a total of 23 near-Earth asteroids from our sample that are likely to be dormant short-period near-Earth comets and, based on a de-biasing procedure applied to the cryogenic NEOWISE survey, estimate both magnitude-limited and size-limited fractions of the NEA population that are dormant short-period comets. We find that 0.3-3.3% of the NEA population with H <= 21, and 9(+2/-5)% of the population with diameters d >= 1 km, are dormant short-period near-Earth comets. We also present an observation program that utilizes the 1.8m Vatican Advanced Technology Telescope (VATT) on Mt. Graham, AZ, to identify dormant comet candidates and search for activity in these objects. Our targets are NEAs on comet-like orbits, based on the dynamical criteria derived in the above study, that are accessible with the VATT (V <= 22). We identify dormant comets based on their optical spectral slope, represented by V-R color measurements, as albedo measurements for most of these objects are not available. For each target we measure and monitor its V magnitude in order to reveal activity outbreaks. We also search for extended emission around our targets using deep imaging and a point

  15. Comparison between air and carbon dioxide insufflation in the endoscopic submucosal excavation of gastrointestinal stromal tumors

    PubMed Central

    Shi, Wei-Bin; Wang, Zi-Hao; Qu, Chun-Ying; Zhang, Yi; Jiang, Han; Zhou, Min; Chen, Ying; Xu, Lei-Ming

    2012-01-01

    AIM: To evaluate the safety and efficacy of CO2 insufflation compared with air insufflation in the endoscopic submucosal excavation (ESE) of gastrointestinal stromal tumors. METHODS: Sixty patients were randomized to undergo endoscopic submucosal excavation, with the CO2 group (n = 30) and the air group (n = 30) undergoing CO2 insufflation and air insufflation in the ESE, respectively. The end-tidal CO2 level (pETCO2) was observed at 4 time points: at the beginning of ESE, at total removal of the tumors, at completed wound management, and 10 min after ESE. Additionally, the patients’ experience of pain at 1, 3, 6 and 24 h after the examination was registered using a visual analog scale (VAS). RESULTS: Both the CO2 group and air group were similar in mean age, sex, body mass index (all P > 0.05). There were no significant differences in PetCO2 values before and after the procedure (P > 0.05). However, the pain scores after the ESE at different time points in the CO2 group decreased significantly compared with the air group (1 h: 21.2 ± 3.4 vs 61.5 ± 1.7; 3 h: 8.5 ± 0.7 vs 42.9 ± 1.3; 6 h: 4.4 ± 1.6 vs 27.6 ± 1.2; 24 h: 2.3 ± 0.4 vs 21.4 ± 0.7, P < 0.05). Meanwhile, the percentage of VAS scores of 0 in the CO2 group after 1, 3, 6 and 24 h was significantly higher than that in the air group (60.7 ± 1.4 vs 18.9 ± 1.5, 81.5 ± 2.3 vs 20.6 ± 1.2, 89.2 ± 0.7 vs 36.8 ± 0.9, 91.3 ± 0.8 vs 63.8 ± 1.3, respectively, P < 0.05). Moreover, the condition of the CO2 group was better than that of the air group with respect to anal exsufflation. CONCLUSION: Insufflation of CO2 in the ESE of gastrointestinal stromal tumors will not cause CO2 retention and it may significantly reduce the level of pain, thus it is safe and effective. PMID:23326136

  16. Electrochemical Properties of Organosilane Self Assembled Monolayers on Aluminum 2024

    NASA Technical Reports Server (NTRS)

    Hintze, Paul E.; Calle, Luz Marina

    2004-01-01

    Self assembled monolayers are commonly used to modify surfaces. Within the last 15 years, self assembled monolayers have been investigated as a way to protect from corrosion[1,2] or biofouling.[3] In this study, self assembled monolayers of decitriethoxysilane (C10H21Si(OC2H5)3) and octadecyltriethoxysilane (C18H37Si(OC2H5)3) were formed on aluminum 2024-T3. The modified surfaces and bare Al 2024 were characterized by dynamic water contact angle measurements, x-ray photoelectron spectroscopy (XIPS) and infrared spectroscopy. Electrochemical impedance spectroscopy (EIS) in 0.5 M NaCl was used to characterize the monolayers and evaluate their corrosion protection properties. The advancing water contact angle and infrared measurements show that the mono layers form a surface where the hydrocarbon chains are packed and oriented away from the surface, consistent with what is found in similar systems. The contact angle hysteresis measured in these systems is relatively large, perhaps indicating that the hydrocarbon chains are not as well packed as monolayers formed on other substrates. The results of the EIS measurements were modeled using a Randle's circuit modified by changing the capacitor to a constant phase element. The constant phase element values were found to characterize the monolayer. The capacitance of the monolayer modified surface starts lower than the bare Al 2024, but approaches values similar to the bare Al 2024 within 24 hours as the monolayer is degraded. The n values found for bare Al 2024 quickly approach the value of a true capacitor and are greater than 0.9 within hours after the start of exposure. For the monolayer modified structure, n can stay lower than 0.9 for a longer period of time. In fact, n for the monolayer modified surfaces is different from the bare surface even after the capacitance values have converged. This indicates that the deviation from ideal capacitance is the most sensitive indicator of the presence of the monolayer.

  17. Repeated-bout exercise in the heat in young athletes: physiological strain and perceptual responses.

    PubMed

    Bergeron, Michael F; Laird, Melissa D; Marinik, Elaina L; Brenner, Joel S; Waller, Jennifer L

    2009-02-01

    A short recovery period between same-day competitions is common practice in organized youth sports. We hypothesized that young athletes will experience an increase in physiological strain and perceptual discomfort during a second identical exercise bout in the heat, with 1 h (21 degrees C) between bouts, even with ample hydration. Twenty-four athletes (6 boys and 6 girls: 12-13 yr old, 47.7 +/- 8.3 kg; 6 boys and 6 girls: 16-17 yr old, 61.0 +/- 8.6 kg) completed two 80-min intermittent exercise bouts (treadmill 60%, cycle 40% peak oxygen uptake) in the heat (33 degrees C, 48.9 +/- 6.1% relative humidity). Sweat loss during each bout was similar within each age group (12-13 yr old: bout 1, 943.6 +/- 237.1 ml; bout 2, 955.5 +/- 250.3 ml; 16-17 yr old: bout 1, 1,382.2 +/- 480.7 ml; bout 2, 1,373.1 +/- 472.2 ml). Area under the curve (AUC) was not statistically different (P > 0.05) between bouts for core body temperature (12-13 yr old: bout 1 peak, 38.6 +/- 0.4 degrees C; bout 2, 38.4 +/- 0.2 degrees C; 16-17 yr old: bout 1 peak, 38.8 +/- 0.7 degrees C; bout 2, 38.7 +/- 0.6 degrees C), physiological strain index (12-13 yr old: bout 1 peak, 7.9 +/- 0.9; bout 2, 7.5 +/- 0.7; 16-17 yr old: bout 1 peak, 8.1 +/- 1.5; bout 2, 7.9 +/- 1.4), or thermal sensation for any age/sex subgroup or for all subjects combined. However, rating of perceived exertion AUC and peak were higher (P = 0.0090 and 0.0004, respectively) during bout 2 in the older age group. Notably, four subjects experienced consistently higher responses throughout bout 2. With these healthy, fit, young athletes, 1 h of complete rest, cool down, and rehydration following 80 min of strenuous exercise in the heat was generally effective in eliminating any apparent carryover effects that would have resulted in greater thermal and cardiovascular strain during a subsequent identical exercise bout.

  18. Occurrence and characterization of Shiga toxin-producing Escherichia coli O157:H7 and other non-sorbitol-fermenting E. coli in cattle and humans in urban areas of Morogoro, Tanzania.

    PubMed

    Lupindu, Athumani M; Olsen, John E; Ngowi, Helena A; Msoffe, Peter L M; Mtambo, Madundo M; Scheutz, Flemming; Dalsgaard, Anders

    2014-07-01

    Escherichia coli strains such as Shiga toxin-producing E. coli (STEC), enteropathogenic E. coli, enterotoxigenic, attaching, and effacing E. coli, and enteroinvasive E. coli cause diarrhea in humans. Although other serotypes exist, the most commonly reported STEC in outbreaks is O157:H7. A cross-sectional study was conducted to isolate and characterize non-sorbitol-fermenting (NSF) E. coli O157:H7 from urban and periurban livestock settings of Morogoro, Tanzania. Human stool, cattle feces, and soil and water samples were collected. Observations and questionnaire interview studies were used to gather information about cattle and manure management practices in the study area. E. coli were isolated on sorbitol MacConkey agar and characterized by conventional biochemical tests. Out of 1049 samples, 143 (13.7%) yielded NSF E. coli. Serological and antimicrobial tests and molecular typing were performed to NSF E. coli isolates. These procedures detected 10 (7%) pathogenic E. coli including STEC (n=7), enteropathogenic E. coli (EPEC) (n=2), and attaching and effacing E. coli (A/EEC) (n=1) strains. The STEC strains had the ability to produce VT1 and different VT2 toxin subtypes that caused cytopathic effects on Vero cells. The prevalence of STEC in cattle was 1.6%, out of which 0.9% was serotype O157:H7 and the overall prevalence of diarrheagenic E. coli in cattle was 2.2%. The serotypes O157:H7, O142:H34, O113:H21, O+:H-, O+:H16, and O25:H4 were identified. One ESBL-producing isolate showed the MLST type ST131. To our knowledge, this is the first finding in Tanzania of this recently emerged worldwide pandemic clonal group, causing widespread antimicrobial-resistant infections, and adds knowledge of the geographical distribution of ST131. Cattle manure was indiscriminately deposited within residential areas, and there was direct contact between humans and cattle feces during manure handling. Cattle and manure management practices expose humans, animals, and the environment

  19. Gravity-driven membrane filtration as pretreatment for seawater reverse osmosis: linking biofouling layer morphology with flux stabilization.

    PubMed

    Akhondi, Ebrahim; Wu, Bing; Sun, Shuyang; Marxer, Brigit; Lim, Weikang; Gu, Jun; Liu, Linbo; Burkhardt, Michael; McDougald, Diane; Pronk, Wouter; Fane, Anthony G

    2015-03-01

    In this study gravity-driven membrane (GDM) ultrafiltration is investigated for the pretreatment of seawater before reverse osmosis (RO). The impacts of temperature (21 ± 1 and 29 ± 1 °C) and hydrostatic pressure (40 and 100 mbar) on dynamic flux development and biofouling layer structure were studied. The data suggested pore constriction fouling was predominant at the early stage of filtration, during which the hydrostatic pressure and temperature had negligible effects on permeate flux. With extended filtration time, cake layer fouling played a major role, during which higher hydrostatic pressure and temperature improved permeate flux. The permeate flux stabilized in a range of 3.6 L/m(2) h (21 ± 1 °C, 40 mbar) to 7.3 L/m(2) h (29 ± 1 °C, 100 mbar) after slight fluctuations and remained constant for the duration of the experiments (almost 3 months). An increase in biofouling layer thickness and a variable biofouling layer structure were observed over time by optical coherence tomography and confocal laser scanning microscopy. The presence of eukaryotic organisms in the biofouling layer was observed by light microscopy and the microbial community structure of the biofouling layer was analyzed by sequences of 16S rRNA genes. The magnitude of permeate flux was associated with the combined effect of the biofouling layer thickness and structure. Changes in the biofouling layer structure were attributed to (1) the movement and predation behaviour of the eukaryotic organisms which increased the heterogeneous nature of the biofouling layer; (2) the bacterial debris generated by eukaryotic predation activity which reduced porosity; (3) significant shifts of the dominant bacterial species over time that may have influenced the biofouling layer structure. As expected, most of the particles and colloids in the feed seawater were removed by the GDM process, which led to a lower RO fouling potential. However, the dissolved organic carbon in the

  20. Isolation and Characteristics of Shiga Toxin 2f-Producing Escherichia coli among Pigeons in Kyushu, Japan

    PubMed Central

    Murakami, Koichi; Etoh, Yoshiki; Ichihara, Sachiko; Maeda, Eriko; Takenaka, Shigeyuki; Horikawa, Kazumi; Narimatsu, Hiroshi; Kawano, Kimiko; Kawamura, Yoshiaki; Ito, Kenitiro

    2014-01-01

    An increasing number of Shiga toxin 2f-producing Escherichia coli (STEC2f) infections in humans are being reported in Europe, and pigeons have been suggested as a reservoir for the pathogen. In Japan, there is very little information regarding carriage of STEC2f by pigeons, prompting the need for further investigation. We collected 549 samples of pigeon droppings from 14 locations in Kyushu, Japan, to isolate STEC2f and to investigate characteristics of the isolates. Shiga toxin stx2f gene fragments were detected by PCR in 16 (2.9%) of the 549 dropping samples across four of the 14 locations. We obtained 23 STEC2f-isolates from seven of the original samples and from three pigeon dropping samples collected in an additional sampling experiment (from a total of seven locations across both sampling periods). Genotypic and phenotypic characteristics were then examined for selected isolates from each of 10 samples with pulsed-field gel electrophoresis profiles. Eight of the stx2f gene fragments sequenced in this study were homologous to others that were identified in Europe. Some isolates also contained virulence-related genes, including lpfAO26, irp2, and fyuA, and all of the 10 selected isolates maintained the eae, astA, and cdt genes. Moreover, five of the 10 selected isolates contained sfpA, a gene that is restricted to Shiga toxin-producing E. coli O165:H2 and sorbitol-fermenting Shiga toxin-producing E. coli O157:NM. We document serotypes O152:HNM, O128:HNM, and O145:H34 as STEC2f, which agrees with previous studies on pigeons and humans. Interestingly, O119:H21 was newly described as STEC2f. O145:H34, with sequence type 722, was described in a German study in humans and was also isolated in the current study. These results revealed that Japanese zoonotic STEC2f strains harboring several virulence-related factors may be of the same clonal complexes as some European strains. These findings provide useful information for public health-related disease management

  1. Characteristics of the Shiga-toxin-producing enteroaggregative Escherichia coli O104:H4 German outbreak strain and of STEC strains isolated in Spain.

    PubMed

    Mora, Azucena; Herrrera, Alexandra; López, Cecilia; Dahbi, Ghizlane; Mamani, Rosalia; Pita, Julia M; Alonso, María P; Llovo, José; Bernárdez, María I; Blanco, Jesús E; Blanco, Miguel; Blanco, Jorge

    2011-09-01

    A Shiga-toxin-producing Escherichia coli (STEC) strain belonging to serotype O104:H4, phylogenetic group B1 and sequence type ST678, with virulence features common to the enteroaggregative E. coli (EAEC) pathotype, was reported as the cause of the recent 2011 outbreak in Germany. The outbreak strain was determined to carry several virulence factors of extraintestinal pathogenic E. coli (ExPEC) and to be resistant to a wide range of antibiotics. There are only a few reports of serotype O104:H4, which is very rare in humans and has never been detected in animals or food. Several research groups obtained the complete genome sequence of isolates of the German outbreak strain as well as the genome sequences of EAEC of serotype O104:H4 strains from Africa. Those findings suggested that horizontal genetic transfer allowed the emergence of the highly virulent Shiga-toxin-producing enteroaggregative E. coli (STEAEC) O104:H4 strain responsible for the outbreak in Germany. Epidemiologic investigations supported a linkage between the outbreaks in Germany and France and traced their origin to fenugreek seeds imported from Africa. However, there has been no isolation of the causative strain O104:H4 from any of the samples of fenugreek seeds analyzed. Following the German outbreak, we conducted a large sampling to analyze the presence of STEC, EAEC, and other types of diarrheagenic E. coli strains in Spanish vegetables. During June and July 2011, 200 vegetable samples from different origins were analyzed. All were negative for the virulent serotype O104:H4 and only one lettuce sample (0.6%) was positive for a STEC strain of serotype O146:H21 (stx1, stx2), considered of low virulence. Despite the single positive case, the hygienic and sanitary quality of Spanish vegetables proved to be quite good. In 195 of the 200 samples (98%), <10 colony-forming units (cfu) of E. coli per gram were detected, and the microbiological levels of all samples were satisfactory (<100 cfu/g). The

  2. Relationship Between Lower Limb Muscle Activity and Platform Acceleration During Whole-Body Vibration Exercise.

    PubMed

    Lienhard, Karin; Vienneau, Jordyn; Nigg, Sandro; Meste, Olivier; Colson, Serge S; Nigg, Benno M

    2015-10-01

    The purpose of this study was to identify the influence of different magnitudes and directions of the vibration platform acceleration on surface electromyography (sEMG) during whole-body vibration (WBV) exercises. Therefore, a WBV platform was used that delivers vertical vibrations by a side-alternating mode, horizontal vibrations by a circular mode, and vibrations in all 3 planes by a dual mode. Surface electromyography signals of selected lower limb muscles were measured in 30 individuals while they performed a static squat on a vibration platform. The WBV trials included 2 side-alternating trials (Side-L: 6 Hz, 2.5 mm; Side-H: 16 Hz, 4 mm), 2 circular trials (Circ-L: 14 Hz, 0.8 mm; Circ-H: 43 Hz, 0.8 mm), and 4 dual-mode trials that were the combinations of the single-mode trials (Side-L/Circ-L, Side-L/Circ-H, Side-H/Circ-L, Side-H/Circ-H). Furthermore, control trials without vibration were assessed, and 3-dimensional platform acceleration was quantified during the vibration. Significant increases in the root mean square of the sEMG (sEMGRMS) compared with the control trial were found in most muscles for Side-L/Circ-H (+17 to +63%, p ≤ 0.05), Side-H/Circ-L (+7 to +227%, p ≤ 0.05), and Side-H/Circ-H (+21 to +207%, p < 0.01) and in the lower leg muscles for Side-H (+35 to +138%, p ≤ 0.05). Furthermore, only the vertical platform acceleration showed a linear relationship (r = 0.970, p < 0.001) with the averaged sEMGRMS of the lower limb muscles. Significant increases in sEMGRMS were found with a vertical acceleration threshold of 18 m·s(-2) and higher. The present results emphasize that WBV exercises should be performed on a platform that induces vertical accelerations of 18 m·s(-2) and higher.

  3. In Vitro Bactericidal Effects of 625, 525, and 425 nm Wavelength (Red, Green, and Blue) Light-Emitting Diode Irradiation

    PubMed Central

    Kim, SangWoo; Kim, JiSun; Lim, WonBong; Jeon, SangMi; Kim, OkSu; Koh, Jeong-Tae; Kim, Chang-Su; Choi, HongRan

    2013-01-01

    Abstract Objective: The purpose of this study was to evaluate the relationship of 625, 525, and 425 nm wavelengths, providing average power output and effects on three common pathogenic bacteria. Background data: Ultraviolet (UV) light kills bacteria, but the bactericidal effects of UV may not be unique, as 425 nm produces a similar effect. The bactericidal effects of light-emitting diode (LED) wavelengths such as 625 and 525 nm have not been described. Before conducting clinical trials, the appropriate wavelength with reasonable dose and exposure time should be established. Materials and methods: The bactericidal effects of 625, 525, and 425 nm wavelength LED irradiation were investigated in vitro for the anaerobic bacterium Porphyromonas gingivalis and two aerobes (Staphylococcus aureus and Escherichia coli DH5α). Average power output was 6 mW/cm2 for 1 h. The bacteria were exposed to LED irradiation for 1, 2, 4, and 8 h (21.6, 43.2, 86.4, and 172.8 J/cm2, respectively). LED irradiation was performed during growth on agar and in broth. Control bacteria were incubated without LED irradiation. Bacterial growth was expressed in colony-forming units (CFU) and at an optical density at 600 nm in agar and broth. Results: The bactericidal effect of LED phototherapy depended upon wavelength, power density, bacterial viable number, and bacteria species. The bactericidal effect of 425 and 525 nm irradiation varied depending upon the bacterial inoculation, compared with unirradiated samples and samples irradiated with red light. Especially, P. gingivalis and E. coli DH5α were killed by 425 nm, and S. aureus growth was inhibited by 525 nm. However, the wavelength of 625 nm was not bactericidal for P. gingivalis, E. coli DH5α, or S. aureus. Conclusions: Irradiation at 625 nm light was not bactericidal to S. aureus, E. coli, and P. gingivalis, whereas wavelengths of 425 and 525 nm had bactericidal effects. S. aureus was also killed at 525

  4. From Farm to Table: Follow-Up of Shiga Toxin-Producing Escherichia coli Throughout the Pork Production Chain in Argentina

    PubMed Central

    Colello, Rocío; Cáceres, María E.; Ruiz, María J.; Sanz, Marcelo; Etcheverría, Analía I.; Padola, Nora L.

    2016-01-01

    Pigs are important reservoirs of Shiga toxin-producing Escherichia coli (STEC). The entrance of these strains into the food chain implies a risk to consumers because of the severity of hemolytic uremic syndrome. This study reports the prevalence and characterization of STEC throughout the pork production chain. From 764 samples, 31 (4.05%) were stx positive by PCR screening. At farms, 2.86% of samples were stx positive; at slaughter, 4.08% of carcasses were stx positive and at boning rooms, 6% of samples were stx positive. These percentages decreased in pork meat ready for sale at sales markets (4.59%). From positive samples, 50 isolates could be characterized. At farms 37.5% of the isolates carried stx1/stx2 genes, 37.5% possessed stx2e and 25%, carried only stx2. At slaughter we detected 50% of isolates positive for stx2, 33% for stx2e, and 16% for stx1/stx2. At boning rooms 59% of the isolates carried stx1/stx2, 14% stx2e, and 5% stx1/stx2/stx2e. At retail markets 66% of isolates were positive for stx2, 17% stx2e, and 17% stx1/stx2. For the other virulence factors, ehxA and saa were not detected and eae gene was detected in 12% of the isolates. Concerning putative adhesins, agn43 was detected in 72%, ehaA in 26%, aida in 8%, and iha in 6% of isolates. The strains were typed into 14 E. coli O groups (O1, O2, O8, O15, O20, O35, O69, O78, O91, O121, O138, O142, O157, O180) and 10 H groups (H9, H10, H16, H21, H26, H29, H30, H32, H45, H46). This study reports the prevalence and characterization of STEC strains through the chain pork suggesting the vertical transmission. STEC contamination originates in the farms and is transferred from pigs to carcasses in the slaughter process and increase in meat pork at boning rooms and sales markets. These results highlight the need to implement an integrated STEC control system based on good management practices on the farm and critical control point systems in the food chain. PMID:26903972

  5. Genotypic analyses of shiga toxin-producing Escherichia coli O157 and non-O157 recovered from feces of domestic animals on rural farms in Mexico.

    PubMed

    Amézquita-López, Bianca A; Quiñones, Beatriz; Cooley, Michael B; León-Félix, Josefina; Castro-del Campo, Nohelia; Mandrell, Robert E; Jiménez, Maribel; Chaidez, Cristóbal

    2012-01-01

    Shiga toxin-producing Escherichia coli (STEC) are zoonotic enteric pathogens associated with human gastroenteritis worldwide. Cattle and small ruminants are important animal reservoirs of STEC. The present study investigated animal reservoirs for STEC in small rural farms in the Culiacan Valley, an important agricultural region located in Northwest Mexico. A total of 240 fecal samples from domestic animals were collected from five sampling sites in the Culiacan Valley and were subjected to an enrichment protocol followed by either direct plating or immunomagnetic separation before plating on selective media. Serotype O157:H7 isolates with the virulence genes stx2, eae, and ehxA were identified in 40% (26/65) of the recovered isolates from cattle, sheep and chicken feces. Pulse-field gel electrophoresis (PFGE) analysis grouped most O157:H7 isolates into two clusters with 98.6% homology. The use of multiple-locus variable-number tandem repeat analysis (MLVA) differentiated isolates that were indistinguishable by PFGE. Analysis of the allelic diversity of MLVA loci suggested that the O157:H7 isolates from this region were highly related. In contrast to O157:H7 isolates, a greater genotypic diversity was observed in the non-O157 isolates, resulting in 23 PFGE types and 14 MLVA types. The relevant non-O157 serotypes O8:H19, O75:H8, O111:H8 and O146:H21 represented 35.4% (23/65) of the recovered isolates. In particular, 18.5% (12/65) of all the isolates were serotype O75:H8, which was the most variable serotype by both PFGE and MLVA. The non-O157 isolates were predominantly recovered from sheep and were identified to harbor either one or two stx genes. Most non-O157 isolates were ehxA-positive (86.5%, 32/37) but only 10.8% (4/37) harbored eae. These findings indicate that zoonotic STEC with genotypes associated with human illness are present in animals on small farms within rural communities in the Culiacan Valley and emphasize the need for the development of control

  6. A sequence preference for nucleation of alpha-helix--crystal structure of Gly-L-Ala-L-Val and Gly-L-Ala-L-Leu: some comments on the geometry of leucine zippers.

    PubMed

    Chaturvedi, S; Go, K; Parthasarathy, R

    1991-03-01

    The synthetic peptide Gly-L-Ala-L-Val (C10H19N3O4.3H2O; GAV) crystallizes in the monoclinic space group P21, with a = 8.052(2), b = 6.032(2), c = 15.779(7) A, beta = 98.520(1) degree, V = 757.8 A3, Dx = 1.312 g cm-3, and Z = 2. The peptide Gly-L-Ala-L-Leu (C11H21N3O4.3H2O; GAL) crystallizes in the orthorhombic space group P212121, with a = 6.024(1), b = 8.171(1), c = 32.791(1) A, V = 1614 A3, Dx = 1.289 g cm-3, and Z = 4. Their crystal structures were solved by direct methods using the program SHELXS-86, and refined to an R index of 0.05 for 1489 reflections for GAV and to an R index of 0.05 for 1563 reflections for GAL. The tripeptides exist as a zwitterion in the crystal and assume a near alpha-helical backbone conformation with the following torsion angles: psi 1 = -150.7 degrees; phi 2, psi 2 = -68.7 degrees, -38.1 degrees; phi 3, psi 32 = -74.8 degrees, -44.9 degrees, 135.9 degrees for GAV; psi 1 = -150.3 degrees; phi 2, psi 2 = -67.7 degrees, -38.9 degrees; phi 3, psi 31, psi 32 = -72.2 degrees, -45.3 degrees, 137.5 degrees for GAL. Both the peptide units in both of the tripeptides show significant deviation from planarity [omega 1 = -171.3(6) degrees and omega 2 = -172.0(6) degrees for GAV; omega 1 = -171.9(5) degrees and omega 2 = -173.2(6) degrees for GAL]. The side-chain conformational angles chi 21 and chi 22 are -61.7(5) degrees and 175.7(5) degrees, respectively, for valine, and the side-chain conformations chi 12 and chi 23's are -68.5(5) degrees and (-78.4(6) degrees, 159.10(5) degrees) respectively, for leucine. Each of the tripeptide molecule is held in a near helical conformation by a water molecule that bridges the NH3+ and COO- groups, and acts as the fourth residue needed to complete the turn by forming two hydrogen bonds. Two other water molecules form intermolecular hydrogen bonds in stabilizing the helical structure so that the end result is a column of molecules that looks like an alpha-helix.

  7. Chemical and carbon isotopic evolution of hydrocarbons during prograde metamorphism from 100°C to 550°C: Case study in the Liassic black shale formation of Central Swiss Alps

    NASA Astrophysics Data System (ADS)

    Schwab, Valérie; Spangenberg, Jorge. E.; Grimalt, Joan O.

    2005-04-01

    Hydrocarbon distributions and stable isotope ratios of carbonates (δ 13C car, δ 18O car), kerogen (δ 13C ker), extractable organic matter (δ 13C EOM) and individual hydrocarbons of Liassic black shale samples from a prograde metamorphic sequence in the Swiss Alps were used to identify the major organic reactions with increasing metamorphic grade. The studied samples range from the diagenetic zone (<100°C) to amphibolite facies (˜550°C). The samples within the diagenetic zones (<100 and 150°C) are characterized by the dominance of C <20n-alkanes, suggesting an origin related with marine and/or bacterial inputs. The metamorphic samples (200 to 550°C) have distributions significantly dominated by C 12 and C 13n-alkanes, C 14, C 16 and C 18n-alkylcyclopentanes and to a lesser extend C 15, C 17 and C 21n-alkylcyclohexanes. The progressive 13C-enrichment (up to 3.9‰) with metamorphism of the C >17n-alkanes suggests the occurrence of cracking reactions of high molecular weight compounds. The isotopically heavier (up to 5.6 ‰) C <17n-alkanes in metamorphic samples are likely originated by thermal degradation of long-chain homologous with preferential release of isotopically light C 1 and C 2 radicals. The dominance of specific even C-number n-alkylcyclopentanes suggests an origin related to direct cyclization mechanism (without decarboxylation step) of algal or bacterial fatty acids occurring in reducing aqueous metamorphic fluid conditions. The regular increase of the concentrations of n-alkylcycloalkanes vs. C >13n-alkanes with metamorphism suggests progressive thermal release of kerogen-linked fatty acid precursors and degradation of n-alkanes. Changes of the steroid and terpenoid distributions are clearly related to increasing metamorphic temperatures. The absence of 18α(H)-22,29,30-trisnorneohopane (Ts), the occurrence of 17β(H)-trisnorhopane, 17β(H), 21α(H)-hopanes in the C 29 to C 31 range and 5α(H),14α(H),17α(H)-20R C 27, C 29 steranes in the

  8. Unexpected ring-closure products derived from 3-(2-allylanilino)-3-phenylacrylate esters: crystal and molecular structures of 3-acetyl-8-allyl-6-methyl-2-phenylquinolin-4-yl acetate and (2RS)-2,8-dimethyl-4-phenyl-1,2-dihydro-6H-pyrrolo[3,2,1-ij]quinolin-6-one.

    PubMed

    Luque, Adriana L; Sanabria, Carlos M; Palma, Alirio; Cobo, Justo; Glidewell, Christopher

    2016-08-01

    The reactions of two 3-(2-allylanilino)-3-phenylacrylate esters with acetic anhydride and with strong acids has revealed a richly diverse reactivity providing a number of unexpected products. Thus, acetylation of ethyl 3-(2-allylanilino)-3-phenylacrylate, (Ia), or ethyl 3-(2-allyl-4-methylanilino)-3-phenylacrylate, (Ib), with acetic anhydride yields not only the expected acetylated esters, (II), as the major products but also the unexpected polysubstituted quinolines 3-acetyl-8-allyl-2-phenylquinolin-4-yl acetate, (IIIa), and 3-acetyl-8-allyl-6-methyl-2-phenylquinolin-4-yl acetate, (IIIb), as minor products. Subsequent reaction of the major product ethyl 2-[(2-allyl-4-methylanilino)(phenyl)methylidene]-3-oxobutanoate, (IIb), with concentrated sulfuric acid did not provide the expected 3-acetylquinoline derivative, but instead two unexpected products, namely ethyl 4-ethyl-2-phenyl-1,4-dihydroquinoline-3-carboxylate, (IV), and ethyl 3-acetyl-4-ethyl-2-phenyl-3,4-dihydroquinoline-3-carboxylate, (V), in yields of 39 and 22%, respectively. The reaction of (Ib) with Eaton's reagent gave both the quinoline (Z)-6-methyl-2-phenyl-8-(prop-1-en-1-yl)quinolin-4(1H)-one, (VI), and the unexpected tricyclic product (2RS)-2,8-dimethyl-4-phenyl-1,2-dihydro-6H-pyrrolo[3,2,1-ij]quinolin-6-one, (VII), in yields of 71 and 12%, respectively. The products (II)-(VII) have all been fully characterized spectroscopically and the crystal structures of two of the unexpected products, i.e. (IIIb) (C23H21NO3) and (VII) (C19H17NO), are reported here. The formation of compounds (IV), (V) and (VII) all require an isomerization of the initial allyl substituent, with migration of the C=C double bond from the terminal site to the internal site. In (IIIb), the two acetyl substituents are oriented such that the intramolecular distance between the two carbonyl O atoms is only 3.243 (2) Å, and in (VII), the five-membered ring adopts a twisted half-chair conformation. The molecules of compound (IIIb

  9. Influence of Relief on Vegetation Factors and Agrotechnical Differentiation Measures in Transylvania Plain

    NASA Astrophysics Data System (ADS)

    Ioana Moraru, Paula; Rusu, Teodor; Bogdan, Ileana; Ioan Pop, Adrian

    2016-04-01

    Transylvanian Plain (TP), with an area of 395.616 hectares, has a special importance for Romanian agriculture being characterized as a region orographically represented by hilly areas hills whereas climatically appears as a plain. Physical-geographical conditions from TP (low level of forestation; climate specific to plains) have resulted in numerous land degradation phenomena: land erosion, landslide, draining of gradient springs and groundwater level. These conditions create a favourable framework for the development of anthropic morphogenetic processes, as well as those triggered by natural mechanisms, thus intensifying the pace and their territorial expansion. Rainfall, through annual distribution and spring-summer pluvial aggressiveness, require the implementation of preservation measures on arable land, particularly for spring cultures. Along with rainfall, more factors are involved: relief, by the high degree of fragmentation and through tilting slopes; vegetation, by the dominance of cultivated plants and by the advanced state of degradation of vegetal grasslands (especially on southern slopes); lithology, by the predominance of loose rocks (sand, marl, sandstone etc.). In order to determine the influence of landscape morphology on the agro-technical characterization of land, 11 HOBO Micro Stations (H21-002) have been implemented from April to October in the locality Caianu, at various altitudes (311-441 m) at exposure coverage (N, NW, W, S, SE, E, NE). HOBO Smart Temp (S-TMB-M002) temperature sensors and Decagon EC-5 (S-SMC-M005) moisture sensors were connected to HOBO Micro Stations. Additionally, in 4 of the 11 sites, tipping bucket rain gauges (RG3-M) were deployed to measure precipitation. Each station stored electronic data regarding ground temperature at 3 depths (10, 20, 30 cm), humidity at a depth of 10 cm, air temperature (1 m) and precipitation. Data were downloaded from the Micro Stations via a laptop computer using HOBOware Pro Software Version

  10. Metabolite discovery of helicidum in rat urine with XCMS based on the data of ultra performance liquid chromatography coupled to time-of-flight mass spectrometry.

    PubMed

    Liu, Qingfei; Shi, Yun; Guo, Tuo; Wang, Yong; Cong, Wenjuan; Zhu, Jingjie

    2012-10-15

    acetylation (C(16)H(22)O(8)). For the other three metabolites, C(11)H(19)N(3)O(9), C(11)H(21)N(3)O(9), and C(14)H(15)NO(7), the bio-transformation mechanisms remain unknown and need further investigation. Calculated as mass of helicidum, the cumulative urine excretion rate of the metabolites was 8.39%. The amount of oxidized helicidum was more than 50% among the metabolites while the parent compound helicidum was 13.28% and the reduced helicidum 11.72%, indicating that oxidation was the major bio-transformation that occurred in vivo.

  11. Effects of variations in flow characteristics through W.P. Franklin Lock and Dam on downstream water quality in the Caloosahatchee River Estuary and in McIntyre Creek in the J.N. “Ding” Darling National Wildlife Refuge, southern Florida, 2010–13

    USGS Publications Warehouse

    Booth, Amanda C.; Soderqvist, Lars E.; Knight, Travis M.

    2016-05-17

    Franklin Lock increases. The highest FDOM recorded during a survey was at Billy’s Creek. Chlorophyll fluorescence was positively correlated with flow at Franklin Lock, with 23 percent of the variation explained by the flow rate at Franklin Lock. An increase in flow rate at Franklin Lock resulted in a decrease in pH (21 percent of variation explained by flow rates). Data from the pH surveys indicate an increase in pH with distance from Franklin Lock. Turbidity and dissolved oxygen near the surface in McIntyre Creek were not correlated with flow rate at Franklin Lock. Moving-boat surveys did not document a change in turbidity or dissolved oxygen with a change in distance from the Franklin Lock. Correlations between Franklin Lock flow rate and water quality in McIntyre Creek indicate that releases at Franklin Lock affect water quality in the Caloosahatchee River Estuary and Ding Darling Refuge.

  12. The solvent-extractable organic compounds in the Indonesia biomass burning aerosols - characterization studies

    NASA Astrophysics Data System (ADS)

    Fang, M.; Zheng, M.; Wang, F.; To, K. L.; Jaafar, A. B.; Tong, S. L.

    for n-alkanols, and the presence of abundant moretane (17 β(H), 21 α(H)-hopanes). The biomarkers dehydroabietic acid and retene were not found in the samples suggesting there is a difference in the long-distance transport samples of an Asian forest fire and the controlled experiments reported in the literature. Similar to the biomass burning in Amazonia (Abas et al., 1995), the present study also showed an absence of conifer tracers in the smoke aerosols indicating tropical wood sources. Abundant friedelin, a specific biomarker for smoke from oak wood fires (Standley and Simoneit, 1990), was present in the late September samples when the fire was more intense. The results were compared to literature values from an earlier study of the haze episode on 29 September 1991 in Kuala Lumpur, Malaysia (Abas and Simoneit, 1996).

  13. Incidence and Virulence Determinants of Verocytotoxin-Producing Escherichia coli Infections in the Brussels-Capital Region, Belgium, in 2008–2010

    PubMed Central

    De Gheldre, Yves; Dediste, Anne; de Moreau, Anne-Isabelle; Mascart, Georges; Simon, Anne; Allemeersch, Daniël; Scheutz, Flemming; Lauwers, Sabine; Piérard, Denis

    2012-01-01

    The incidence of verocytotoxin-producing Escherichia coli (VTEC) was investigated by PCR in all human stools from Universitair Ziekenhuis Brussel (UZB) and in selected stools from six other hospital laboratories in the Brussels-Capital Region, Belgium, collected between April 2008 and October 2010. The stools selected to be included in this study were those from patients with hemolytic-uremic syndrome (HUS), patients with a history of bloody diarrhea, patients linked to clusters of diarrhea, children up to the age of 6 years, and stools containing macroscopic blood. Verocytotoxin genes (vtx) were detected significantly more frequently in stools from patients with the selected conditions (2.04%) than in unselected stools from UZB (1.20%) (P = 0.001). VTEC was detected most frequently in patients with HUS (35.3%), a history of bloody diarrhea (5.15%), or stools containing macroscopic blood (1.85%). Stools from patients up to the age of 17 years were significantly more frequently vtx positive than those from adult patients between the ages of 18 and 65 years (P = 0.022). Although stools from patients older than 65 years were also more frequently positive for vtx than those from patients between 18 and 65 years, this trend was not significant. VTEC was isolated from 140 (67.9%) vtx-positive stools. One sample yielded two different serotypes; thus, 141 isolates could be characterized. Sixty different O:H serotypes harboring 85 different virulence profiles were identified. Serotypes O157:H7/H− (n = 34), O26:H11/H− (n = 21), O63:H6 (n = 8), O111:H8/H− (n = 7), and O146:H21/H− (n = 6) accounted for 53.9% of isolates. All O157 isolates carried vtx2, eae, and a complete O island 122 (COI-122); 15 also carried vtx1. Non-O157 isolates (n = 107), however, accounted for the bulk (75.9%) of isolates. Fifty-nine (55.1%) isolates were positive for vtx1, 36 (33.6%) were positive for vtx2, and 12 (11.2%) carried both vtx1 and vtx2. Pulsed-field gel electrophoresis revealed

  14. A Literature Survey to Identify Potentially Volatile Iodine-Bearing Species Present in Off-Gas Streams

    SciTech Connect

    Bruffey, S. H.; Spencer, B. B.; Strachan, D. M.; Jubin, R. T.; Soelberg, N. R.; Riley, B. J.

    2015-06-30

    Four radionuclides have been identified as being sufficiently volatile in the reprocessing of nuclear fuel that their gaseous release needs to be controlled to meet regulatory requirements (Jubin et al. 2011, 2012). These radionuclides are 3H, 14C, 85Kr, and 129I. Of these, 129I has the longest half-life and potentially high biological impact. Accordingly, control of the release of 129I is most critical with respect to the regulations for the release of radioactive material in stack emissions. It is estimated that current EPA regulations (EPA 2010) would require any reprocessing plant in the United States to limit 129I release to less than 0.05 Ci/MTIHM for a typical fuel burnup of 55 gigawatt days per metric tonne (GWd/t) (Jubin 2011). The study of inorganic iodide in off-gas systems has been almost exclusively limited to I2 and the focus of organic iodide studies has been CH3I. In this document, we provide the results of an examination of publically available literature that is relevant to the presence and sources of both inorganic and organic iodine-bearing species in reprocessing plants. We especially focus on those that have the potential to be poorly sequestered with traditional capture methodologies. Based on the results of the literature survey and some limited thermodynamic modeling, the inorganic iodine species hypoiodous acid (HOI) and iodine monochloride (ICl) were identified as potentially low-sorbing iodine species that could present in off-gas systems. Organic species of interest included both short chain alkyl iodides such as methyl iodide (CH3I) and longer alkyl iodides up to iodododecane (C10H21I). It was found that fuel dissolution may provide conditions conducive to HOI formation and has been shown to result in volatile long-chain alkyl iodides, though these may not volatilize until later in the reprocessing sequence. Solvent extraction processes were found to be significant sources of various organic iodine-bearing species; formation of these

  15. Effects of variations in flow characteristics through W.P. Franklin Lock and Dam on downstream water quality in the Caloosahatchee River Estuary and in McIntyre Creek in the J.N. “Ding” Darling National Wildlife Refuge, southern Florida, 2010–13

    USGS Publications Warehouse

    Booth, Amanda C.; Soderqvist, Lars E.; Knight, Travis M.

    2016-01-01

    Franklin Lock increases. The highest FDOM recorded during a survey was at Billy’s Creek. Chlorophyll fluorescence was positively correlated with flow at Franklin Lock, with 23 percent of the variation explained by the flow rate at Franklin Lock. An increase in flow rate at Franklin Lock resulted in a decrease in pH (21 percent of variation explained by flow rates). Data from the pH surveys indicate an increase in pH with distance from Franklin Lock. Turbidity and dissolved oxygen near the surface in McIntyre Creek were not correlated with flow rate at Franklin Lock. Moving-boat surveys did not document a change in turbidity or dissolved oxygen with a change in distance from the Franklin Lock. Correlations between Franklin Lock flow rate and water quality in McIntyre Creek indicate that releases at Franklin Lock affect water quality in the Caloosahatchee River Estuary and Ding Darling Refuge.

  16. Characterization of Lunar Crater Ejecta Deposits Using Radar Data from the Mini-RF Instrument on LRO

    NASA Astrophysics Data System (ADS)

    Patterson, G. W.; Raney, R. K.; Cahill, J. T.; Bussey, B.

    2012-12-01

    of up to ~1 m. As observed with visible image data, the increased roughness as-sociated with the ejecta of Byrgius A appears nearly continuous to a radial distance of ~70 km. An m-chi decomposition of Mini-RF S-band data for Byrgius A suggests that the portion of ejecta that extends radially from ~10 to 70 km appears far less continuous than is suggested in both optical data and CPR information (Fig. 1). The implication is that we are observing properties of the ejecta and lunar background terrain in the top meter of the surface. In other words the thickness of the ejecta in this distance range is on the order of meters or less. This result suggests that the thickness of ejecta at radial distances > a crater radius differ significantly from estimates of ejecta thickness derived from models of ejecta emplacement [6,7]. References: [1] Melosh, H. J. (1989), Oxford Univ. Press; [2] Ghent, R. R. et al. (2008), Geology, 36, 343-346; [3] Raney, R. K. et al. (2011), Proc. of the IEEE, 99, 808-823; [4] Raney, R.K. et al. (2012), JGR, 117, E00H21; [5] Robinson, M. S. et al. (2010), Space Sci. Rev., 150, 81-124; [6] McGetchin et al. (1973), EPSL, 20, 226-236; [7] Pike (1974), EPSL, 23, 265-274.

  17. Effect of water and feed withdrawal and health status on blood and serum components, body weight loss, and meat and carcass characteristics of Holstein slaughter cows.

    PubMed

    Vogel, K D; Claus, J R; Grandin, T; Oetzel, G R; Schaefer, D M

    2011-02-01

    During marketing, cattle may be exposed to periods of water deprivation. The impact of water and feed access and health status on the physiological well-being and carcass characteristics of Holstein slaughter cows during preslaughter marketing was studied through analysis of serum components, BW loss percentage, and fresh meat composition. Ninety-one multiparous Holstein cows (609 ± 89 kg mean BW, 2.9 ± 0.5 mean BCS, varying stage of lactation) were purchased over 3 wk in 3 groups (n = 31, 29, and 31) at a terminal market in central Wisconsin. Each cow was screened to determine health status (sick or not sick) and randomly assigned to 1 of 3 water and feed withdrawal treatment pens (AL, ad libitum access to water for 36 h; 18H, 18 h of ad libitum access to water followed by 18 h of water withdrawal; 36H, 36 h of water withdrawal; all 3 treatments included 36 h of feed withdrawal) in a randomized complete block arrangement with repeated measures for serum components. Blood samples were collected by tail venipuncture at 0, 9, 18, 27, and 36 h of each treatment. Ambient temperatures were 1.9 ± 6.2°C during the trial period, which occurred over a 3-wk period in March and April 2007 near Arlington, WI. No difference (P > 0.05) was observed in mean serum cortisol in AL (18.41 ± 2.17 ng/mL) or 36H (22.98 ± 2.17 ng/mL). Mean serum glucose was greater (P < 0.05) in 36H pens (78.15 ± 0.77 mg/dL) than AL (75.91 ± 0.77 mg/dL). Mean serum creatinine was greater (P < 0.05) in 36H pens (0.71 ± 0.03 mg/dL) than AL (0.60 ± 0.03 mg/dL). The 36H pens also displayed increased (P < 0.05) serum albumin, anion gap, Ca, Cl, Na, cholesterol, and aspartate aminotransferase over AL. Greater (P < 0.05) mean percentage BW loss was observed in 36H pens (5.2 ± 0.6%) than AL (3.1 ± 0.6%). Mean muscle protein (%) was greater (P < 0.05) in 36H (22.2 ± 0.4%) than 18H (21.3 ± 0.4%). Mean muscle moisture (%) was greater (P < 0.05) in AL and 18H (75.3 ± 0.4% and 75.2 ± 0.4%) than 36H

  18. Effect of water and feed withdrawal and health status on blood and serum components, body weight loss, and meat and carcass characteristics of Holstein slaughter cows.

    PubMed

    Vogel, K D; Claus, J R; Grandin, T; Oetzel, G R; Schaefer, D M

    2011-02-01

    During marketing, cattle may be exposed to periods of water deprivation. The impact of water and feed access and health status on the physiological well-being and carcass characteristics of Holstein slaughter cows during preslaughter marketing was studied through analysis of serum components, BW loss percentage, and fresh meat composition. Ninety-one multiparous Holstein cows (609 ± 89 kg mean BW, 2.9 ± 0.5 mean BCS, varying stage of lactation) were purchased over 3 wk in 3 groups (n = 31, 29, and 31) at a terminal market in central Wisconsin. Each cow was screened to determine health status (sick or not sick) and randomly assigned to 1 of 3 water and feed withdrawal treatment pens (AL, ad libitum access to water for 36 h; 18H, 18 h of ad libitum access to water followed by 18 h of water withdrawal; 36H, 36 h of water withdrawal; all 3 treatments included 36 h of feed withdrawal) in a randomized complete block arrangement with repeated measures for serum components. Blood samples were collected by tail venipuncture at 0, 9, 18, 27, and 36 h of each treatment. Ambient temperatures were 1.9 ± 6.2°C during the trial period, which occurred over a 3-wk period in March and April 2007 near Arlington, WI. No difference (P > 0.05) was observed in mean serum cortisol in AL (18.41 ± 2.17 ng/mL) or 36H (22.98 ± 2.17 ng/mL). Mean serum glucose was greater (P < 0.05) in 36H pens (78.15 ± 0.77 mg/dL) than AL (75.91 ± 0.77 mg/dL). Mean serum creatinine was greater (P < 0.05) in 36H pens (0.71 ± 0.03 mg/dL) than AL (0.60 ± 0.03 mg/dL). The 36H pens also displayed increased (P < 0.05) serum albumin, anion gap, Ca, Cl, Na, cholesterol, and aspartate aminotransferase over AL. Greater (P < 0.05) mean percentage BW loss was observed in 36H pens (5.2 ± 0.6%) than AL (3.1 ± 0.6%). Mean muscle protein (%) was greater (P < 0.05) in 36H (22.2 ± 0.4%) than 18H (21.3 ± 0.4%). Mean muscle moisture (%) was greater (P < 0.05) in AL and 18H (75.3 ± 0.4% and 75.2 ± 0.4%) than 36H

  19. Automation of Eastern Kentucky University Observatory and Preliminary Data

    NASA Astrophysics Data System (ADS)

    Ciocca, M.; Kilgore, E. E.; Williams, W. W.

    2012-06-01

    (Abstract only) Eastern Kentucky University is a regional comprehensive institution located in Richmond, Kentucky. Its service area includes much of the eastern part of Kentucky, commonly referred to as Appalachia. As such, Eastern has truly been a "school of opportunities" for the region. We offer three astronomy courses and one of them, AST 135, has an outdoor lab component, in which the students observe the moon and the brightest planets using 6-inch SCT. To expand our offerings by adding advanced classes in observational astronomy, and with support from the University and a small grant from the AAS (Small Research Grants), we constructed a small observatory for that purpose. We have a 14-inch telescope (C14 from Celestron), with a research grade mount (Paramount ME), housed permanently in a two-room facility. The telescope room has a retractable roof and the control room is insulated against the elements. The telescope is conveniently located near campus, in a location away from city lights and vehicular traffic, with access via a secure gate. The observatory is on a concrete pad poured directly onto the ground, to minimize vibrations. The instrument package consists of a SBIG STL-6303E CCD camera with filter wheel and full complement of photographic, narrow-band, and photometric filters (Ha and UBVRI). Courtesy of the AAS grant, we also have a temperature-compensated focuser (TCF-S3i), off-axis guider, and SBIG AO-L adaptive optics accessory. Our first step has been the measurement of our CCD transformation parameters, to assess the capabilities of our telescope-camera combination. We imaged a standard photometric field from Landolt (1992) (R.A. 09h 21m 32s, Dec. +02° 47' 00" (J2000, Plate 38 of Landolt). Data were obtained with a time integration of 90 seconds, binned 2 x 2 (~1 arcsec/pixel) at air mass X = 1.31. We determined the CCD transformation parameter as described by the AAVSO document "Computing and Using CCD transformation coefficients" (Cohen 2003

  20. Global system for hydrological monitoring and forecasting in real time at high resolution

    NASA Astrophysics Data System (ADS)

    Ortiz, Enrique; De Michele, Carlo; Todini, Ezio; Cifres, Enrique

    2016-04-01

    connection) and not need update (all upgrade are deployed on the remote server)and DSS is a classical client-server application. The client side will be an HTML 5-CSS 3 application, it runs in one of the most common browser. The server side consist in: A web server (Apache web server); a map server (Geoserver); a Geographical q3456Relational Database Management Sytem (Postgresql+Postgis); Tools based on GDAL Lybraries. A customized web page will be implemented to publish all hydrometeorological information and forecast runs (free) for all users in the world. In this first presentation of the project are invited to attend all those scientific / technical people, Universities, Research Centers (public or private) who want to collaborate in it, opening a brainstorming to improve the System. References: • Liu Z. and Todini E., (2002). Towards a comprehensive physically based rainfall-runoff model. Hydrology and Earth System Sciences (HESS), 6(5):859-881, 2002. • Thielen, J., Bartholmes, J., Ramos, M.-H., and de Roo, A., (2009): The European Flood Alert System - Part 1: Concept and development, Hydrol. Earth Syst. Sci., 13, 125-140, 2009. • Coccia C., Mazzetti C., Ortiz E., Todini E., (2010) - A different soil conceptualization for the TOPKAPI model application within the DMIP 2. American Geophysical Union. Fall Meeting, San Francisco H21H-07, 2010. • Pappenberger, F., Cloke, H. L., Balsamo, G., Ngo-Duc, T., and Oki,T., (2010) Global runoff routing with the hydrological component of the ECMWF NWP system, Int. J. Climatol., 30, 2155-2174, 2010. • Coccia, G. and Todini, E., (2011). Recent developments in predictive uncertainty assessment based on the Model Conditional Processor approach. Hydrology and Earth System Sciences, 15, 3253-3274, 2011. • Wu, H., Adler, R. F., Hong, Y., Tian, Y., and Policelli, F.,(2012): Evaluation of Global Flood Detection Using Satellite-Based Rainfall and a Hydrologic Model, J. Hydrometeorol., 13, 1268-1284, 2012. • Simth M. et al., (2013

  1. Global system for hydrological monitoring and forecasting in real time at high resolution

    NASA Astrophysics Data System (ADS)

    Ortiz, Enrique; De Michele, Carlo; Todini, Ezio; Cifres, Enrique

    2016-04-01

    connection) and not need update (all upgrade are deployed on the remote server)and DSS is a classical client-server application. The client side will be an HTML 5-CSS 3 application, it runs in one of the most common browser. The server side consist in: A web server (Apache web server); a map server (Geoserver); a Geographical q3456Relational Database Management Sytem (Postgresql+Postgis); Tools based on GDAL Lybraries. A customized web page will be implemented to publish all hydrometeorological information and forecast runs (free) for all users in the world. In this first presentation of the project are invited to attend all those scientific / technical people, Universities, Research Centers (public or private) who want to collaborate in it, opening a brainstorming to improve the System. References: • Liu Z. and Todini E., (2002). Towards a comprehensive physically based rainfall-runoff model. Hydrology and Earth System Sciences (HESS), 6(5):859-881, 2002. • Thielen, J., Bartholmes, J., Ramos, M.-H., and de Roo, A., (2009): The European Flood Alert System - Part 1: Concept and development, Hydrol. Earth Syst. Sci., 13, 125-140, 2009. • Coccia C., Mazzetti C., Ortiz E., Todini E., (2010) - A different soil conceptualization for the TOPKAPI model application within the DMIP 2. American Geophysical Union. Fall Meeting, San Francisco H21H-07, 2010. • Pappenberger, F., Cloke, H. L., Balsamo, G., Ngo-Duc, T., and Oki,T., (2010) Global runoff routing with the hydrological component of the ECMWF NWP system, Int. J. Climatol., 30, 2155-2174, 2010. • Coccia, G. and Todini, E., (2011). Recent developments in predictive uncertainty assessment based on the Model Conditional Processor approach. Hydrology and Earth System Sciences, 15, 3253-3274, 2011. • Wu, H., Adler, R. F., Hong, Y., Tian, Y., and Policelli, F.,(2012): Evaluation of Global Flood Detection Using Satellite-Based Rainfall and a Hydrologic Model, J. Hydrometeorol., 13, 1268-1284, 2012. • Simth M. et al., (2013

  2. Regio- and Stereoselective 1,3-Dipolar Cycloaddition of Cyclic Azomethine Imines to Platinum(IV)-Bound Nitriles Giving Δ(2)-1,2,4-Triazoline Species.

    PubMed

    Smirnov, Andrey S; Kritchenkov, Andreii S; Bokach, Nadezhda A; Kuznetsov, Maxim L; Selivanov, Stanislav I; Gurzhiy, Vladislav V; Roodt, Andreas; Kukushkin, Vadim Yu

    2015-11-16

    The complex trans-[PtCl4(EtCN)2] (14) reacts smoothly at 25 °C with the stable cyclic azomethine imines R(1)CH═N(a)NC(O)CH(NHC(O)C6H4R(3))C(b)H(C6H4R(2))((a-b)) [R(1)/R(2)/R(3) = p-Me/H/H (8); p-Me/p-Me/H (9); p-Me/p-MeO/H (10); p-Me/p-Cl/p-Cl (11); p-MeO/p-Me/H (12); p-MeO/p-Cl/m-Me (13)], and the reaction proceeds as stereoselective 1,3-dipolar cycloaddition to one of the EtCN ligands accomplishing the monocycloadducts trans-[PtCl4(EtCN){N(a)═C(Et)N(b)C(O)CH(NHC(O)C6H4R(3))CH(C6H4R(2))N(c)C(d)HR(1)}])((a-d;b-c)) [R(1)/R(2)/R(3) = p-Me/H/H (15); p-Me/p-Me/H (16); p-Me/p-MeO/H (17); p-Me/p-Cl/p-Cl (18); p-MeO/p-Me/H (19); p-MeO/p-Cl/m-Me (20)]. Inspection of the obtained and literature data indicate that the cycloaddition of the azomethine imines to the C≡N bonds of HCN and of Pt(IV)-bound EtCN has different regioselectivity leading to Δ(2)-1,2,3-triazolines and Δ(2)-1,2,4-triazolines, respectively. Platinum(II) species trans-[PtCl2(EtCN){N(a)═C(Et)N(b)C(O)CH(NHC(O)C6H4R(3))CH(C6H4R(2))N(c)C(d)HR(1)}]((a-d;b-c)) [R(1)/R(2)/R(3) = p-Me/H/H (21); p-Me/p-Me/H (22); p-Me/p-MeO/H (23); p-Me/p-Cl/p-Cl (24); p-MeO/p-Me/H (25); p-MeO/p-Cl/m-Me (26)] were obtained by a one-pot procedure from 14 and 8-13 followed by addition of the phosphorus ylide Ph3P═CHCO2Me. Δ(2)-1,2,4-Triazolines N(a)═C(Et)N(b)C(O)CH(NHC(O)C6H4R(3))CH(C6H4R(2))N(c)C(d)HR(1(a-d;b-c)) [R(1)/R(2)/R(3) = p-Me/H/H (27); p-Me/p-Me/H (28); p-Me/p-MeO/H (29); p-Me/p-Cl/p-Cl (30); p-MeO/p-Me/H (31); p-MeO/p-Cl/m-Me (32)] were liberated from 21-26 by the treatment with bis(diphenylphosphyno)ethane (dppe). Platinum(II) complexes 21-26 were characterized by elemental analyses (C, H, N), high-resolution electrospray ionization mass spectrometry (ESI-MS), and IR and (1)H and (13)C{(1)H} NMR spectroscopies and single crystal X-ray diffraction in the solid state for 25·CH3OH, 26·(CHCl3)0.84. The structure of 26 was also determined by COSY-90 and NOESY NMR methods in solution. Quantitative evaluation

  3. First Look at a Major Transition Period in the Early Universe

    NASA Astrophysics Data System (ADS)

    1997-08-01

    .885) x 304 A = 1181 A . This far-ultraviolet spectral region is not accessible with ground-based telescopes, but may be observed from above the atmosphere with the orbiting Hubble Space Telescope. [3] Prior to this discovery, the Hamburg group had discovered - between 1989 and 1994 - three other bright and distant quasars with relatively clear lines of sight which have also been observed with the Hubble Space Telescope. Although none of them is distant enough to allow the detection of intergalactic He + with HST, He + -absorption towards one of these objects, HS 1700+6416 was detected by the Hopkins Ultraviolet Telescope during NASA's Astro-2 mission in 1995. The first detection of intergalactic He + was made in 1994 by a group of European astronomers in the quasar Q0302-002 , cf. ESA Press Information Note 17-94 (7 July 1994). [4] An ion is an atom that has lost one or more of its electrons. [5] The ionization potential of hydrogen is 13.6 electron volt (eV), of neutral helium, 24.6 eV, and of singly ionized helium, 54.4 eV. In order to ionize the primordial hydrogen and helium atoms, photons of the indicated energies must be emitted by the first galaxies and stars. The corresponding photon wavelengths, all in the far-ultraviolet spectral region, are 912 A (91.2 nm), 504 A (50.4 nm) and 228 A (22.8 nm), respectively. The (Planck-)temperatures required are of the order of 32,000 K, 58,000 K and 127,000 K, respectively, which shows that the second ionization of helium cannot be done by the radiation from stars - they are not sufficiently hot. Thus He + -ions can only be ionized by the radiation from quasars. How to obtain ESO Press Information ESO Press Information is made available on the World-Wide Web (URL: http://www.eso.org../). ESO Press Photos may be reproduced, if credit is given to the European Southern Observatory.

  4. First look at a major transition period in the early Universe

    NASA Astrophysics Data System (ADS)

    1997-08-01

    with the Hubble Space Telescope. Although none of them is distant enough to allow the detection of intergalactic He+ with HST, He+-absorption towards one of these objects, HS 1700+6416 was detected by the Hopkins Ultraviolet Telescope during NASA's Astro-2 mission in 1995. The first detection of intergalactic He+ was made in 1994 by a group of European astronomers in the quasar Q0302-002, cf. ESA Press Information Note 17-94 (7 July 1994). [4] An ion is an atom that has lost one or more of its electrons. [5] The ionization potential of hydrogen is 13.6 electron volt (eV), of neutral helium, 24.6 eV, and of singly ionized helium, 54.4 eV. In order to ionize the primordial hydrogen and helium atoms, photons of the indicated energies must be emitted by the first galaxies and stars. The corresponding photon wavelengths, all in the far-ultraviolet spectral region, are 912 A (91.2 nm), 504 A (50.4 nm) and 228 A (22.8 nm), respectively. The (Planck-)temperatures required are of the order of 32,000 K, 58,000 K and 127,000 K, respectively, which shows that the second ionization of helium cannot be done by the radiation from stars - they are not sufficiently hot. Thus He+-ions can only be ionized by the radiation from quasars. More information on ESA is available on the World Wide Web at http://www.esa.int ESO Press Information is available at http://www.eso.org/outreach/press-rel/. ESO Photos may be reproduced, if credit is given to the European Southern Observatory.