Nicergoline stimulates protein kinase C mediated alpha-secretase processing of the amyloid precursor protein in cultured human neuroblastoma SH-SY5Y cells.

PubMed

Cedazo-Minguez, A; Bonecchi, L; Winblad, B; Post, C; Wong, E H; Cowburn, R F; Benatti, L

1999-10-01

We investigated the ability of the antidementia agents, nicergoline, aniracetam and hydergine to stimulate PKC mediated alpha-secretase amyloid precursor protein (APP) processing in cultured human neuroblastoma SH-SY5Y cells. Western immunoblotting of cell conditioned media using the Mabs 22C11 and 6E10 revealed the presence of 2 bands with molecular mass of 90 and 120 kDa, corresponding to possible alternatively glycosylated forms of secreted APP (APPs). Short-term (30 min and 2 h) treatment of cells with nicergoline gave an increased intensity of both bands, compared to non-treated cells. Maximal nicergoline effects, of the order of 150-200% over basal APPs release, were seen at concentrations between 1 and 10 microM. Under the same condition, 1 microM PdBu, used as a positive control, gave 500-1000% increases of basal APPs release. In contrast, aniracetam and hydergine, did not show any effect on APPs secretion. 2 h treatment with nicergoline had no effect on cellular full-length APP levels, as determined by immunoblotting of cell extracts with 22C11 and CT15 antibodies. Immunoblotting with PKC isoform specific antibodies of soluble and membrane fractions prepared from 2 h treated cells, showed that nicergoline (50 microM) and PdBu (1 microM) both induced translocation of PKC alpha, gamma and epsilon, but not PKC beta. The involvement of PKC in mediating nicergoline stimulated APPs release was also studied using specific inhibitors. 1 microM calphostin C, a broad range PKC inhibitor, significantly reduced both PdBu (1 microM) and nicergoline (10 microM) induced APPs release. In contrast, Go6976 (1 microM), a selective PKC alpha and beta1 inhibitor, as well as the cAMP-dependent protein kinase inhibitor, H89 (1 microM) were without effect. These results indicate that nicergoline can modulate alpha-secretase APP processing by a PKC dependent mechanism that is likely to involve the gamma and epsilon isoforms of this enzyme.

Intramolecular electron transfer in cyanide bridged adducts comprising Ru(II)/Ru(III) tetracarboxylate and [Mn(I)(CO)(CN)((t)BuNC)(4)] units.

PubMed

Imhof, Wolfgang; Sterzik, Anke; Krieck, Sven; Schwierz, Markus; Hoffeld, Thomas; Spielberg, Eike T; Plass, Winfried; Patmore, Nathan

2010-07-21

Reaction of mixed valence ruthenium tetracarboxylates [Ru(2)(II,III)(R(1)COO)(2)(R(2)COO)(2)Cl] (R(1) = Me, R(2) = 2,4,6-(i)Pr-Ph or R(1) = R(2) = (t)Bu) with two equivalents of the octahedral manganese complex [Mn(I)(CO)(CN)((t)BuNC)(4)] leads to the formation of cyanide bridged heteronuclear coordination compounds of the general formula {[Ru(2)(II,III)(R(1)COO)(2)(R(2)COO)(2)][Mn(I)(CO)(CN)((t)BuNC)(4)](2)}Cl. In solution an intramolecular electron transfer from manganese towards the multiply bonded Ru(2) core occurs that is verified by EPR and IR spectroscopy, magnetic measurements and DFT calculations. Nevertheless, disproportionation of an initially formed {Mn(I)-Ru(2)(II,III)-Mn(I)}(+) adduct into {Mn(II)-Ru(2)(II,III)-Mn(I)}(2+) and {Mn(I)-Ru(2)(II,II)-Mn(I)} species cannot be completely ruled out.

Closure Plan for Corrective Action Unit 109: U-2bu Subsidence Crater Nevada Test Site, Nevada

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shannon Parsons

1999-03-01

The U-2bu subsidence crater, Corrective Action Unit 109, will be closed in accordance with the Resource Conservation and Recovery Act, the Nevada Division of Environmental Protection operational permit, and the Federal Facilities Agreement and Consent Order. The U-2bu subsidence crater is located in Area 2 of the Nevada Test Site. It was created in 1971 by an underground nuclear test with the name Miniata. The crater has a diameter of 288 meters (944 feet) and an approximate depth of 35 meters (115 feet). The subsidence crater was used as a land disposal unit for radioactive and hazardous waste from 1973more » to 1988. Site disposal history is supported by memorandums, letters, and personnel who worked at the Nevada Test Site at the time of active disposal. Closure activities will include the excavation and disposal of impacted soil form the tip of the crater. Upon completion of excavation, verification samples will be collected to show that lead has been removed to concentrations be low regulatory action level. The area will then be backfilled and a soil flood diversion berm will be constructed, and certified by an independent professional engineer as to having followed the approved Closure Plan.« less

Closure plan for Corrective Action Unit 109: U-2bu subsidence crater, Nevada Test Site, Nevada

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1999-03-01

The U-2bu subsidence crater, Corrective Action Unit 109, will be closed in accordance with the Resource Conservation and Recovery Act, the Nevada Division of Environmental Protection operational permit, and the Federal Facility Agreement and Consent Order. The U-2bu subsidence crater is located in Area 2 of the Nevada Test Site. It was created in 1971 by an underground nuclear test with the name Miniata. The crater has a diameter of 288 meters (944 feet) and an approximate depth of 35 meters (115 feet). Based on the results of the analyses reported in the site characterization report, the only constituents ofmore » concern in the U-2bu subsidence crater include leachable lead and total petroleum hydrocarbons. Closure activities will include the excavation and disposal of impacted soil from the top of the crater. Upon completion of excavation, verification samples will be collected to show that the leachable lead has been removed to concentrations below the regulatory action level. After sample results show that the lead has been removed, the excavated area will be backfilled and a soil flood diversion berm will be constructed as a best management practice. An independent registered professional engineer will certify the site was closed following the approved Closure Plan. Post-closure care is not warranted for this site because closure activities will involve removal of the Resource Conservation and Recovery Act constituents of concern.« less

Templating Influence of Molecular Precursors on Pr(OH)3 Nanostructures.

PubMed

Hemmer, Eva; Cavelius, Christian; Huch, Volker; Mathur, Sanjay

2015-07-06

Four new praseodymium alkoxo and amido compounds ([Pr3(μ3-OtBu)2(μ2-OtBu)3(OtBu)4(HOtBu)2] (1), [Pr{OC(tBu)3}3(THF)] (2), [PrCl{N(SiMe3)2}2(THF)]2 (3), and [PrCl{OC(tBu)3}2(THF)]2 (4)) were synthesized and structurally characterized by single-crystal X-ray diffraction analysis. Application of these compounds in solvothermal synthesis of praseodymium oxide/hydroxide nanostructures showed their templating influence on the morphology and phase composition of the resulting solid-state materials. Differential reactivity of the chosen alkoxide ligands toward water and the different arrangements of metal-oxygen units in the studied precursor compounds strongly influenced the kinetics of hydrolysis and cross-condensation reactions as manifested in the morphological changes and phase composition of the final products. Thermal decomposition studies of 1-4 confirmed their conversion into the corresponding oxide phases. Activation of compounds 1, 2, and 4 by either a base or a stoichiometric amount of water showed the distinct influence of their chemical configuration on the obtained nanopowders: whereas 1 solely produced nanorods of Pr(OH)3, 2 predominantly formed a mixture of rod-shaped and spherical particles. The solvothermal decomposition of 4 resulted in Pr(OH)2Cl or PrOCl due to the presence of Cl ligands in the molecular precursor. The resultant materials were thoroughly characterized to demonstrate the relationship between precursor chemistry and the processing parameters that are clearly manifested in the morphology and phase of the final ceramics.

Dinuclear rare-earth metal alkyl complexes supported by indolyl ligands in μ-η(2) :η(1) :η(1) hapticities and their high catalytic activity for isoprene 1,4-cis-polymerization.

PubMed

Zhang, Guangchao; Wei, Yun; Guo, Liping; Zhu, Xiancui; Wang, Shaowu; Zhou, Shuangliu; Mu, Xiaolong

2015-02-02

Two series of new dinuclear rare-earth metal alkyl complexes supported by indolyl ligands in novel μ-η(2) :η(1) :η(1) hapticities are synthesized and characterized. Treatment of [RE(CH2 SiMe3 )3 (thf)2 ] with 1 equivalent of 3-(tBuN=CH)C8 H5 NH (L1 ) in THF gives the dinuclear rare-earth metal alkyl complexes trans-[(μ-η(2) :η(1) :η(1) -3-{tBuNCH(CH2 SiMe3 )}Ind)RE(thf)(CH2 SiMe3 )]2 (Ind=indolyl, RE=Y, Dy, or Yb) in good yields. In the process, the indole unit of L1 is deprotonated by the metal alkyl species and the imino C=N group is transferred to the amido group by alkyl CH2 SiMe3 insertion, affording a new dianionic ligand that bridges two metal alkyl units in μ-η(2) :η(1) :η(1) bonding modes, forming the dinuclear rare-earth metal alkyl complexes. When L1 is reduced to 3-(tBuNHCH2 )C8 H5 NH (L2 ), the reaction of [Yb(CH2 SiMe3 )3 (thf)2 ] with 1 equivalent of L2 in THF, interestingly, generated the trans-[(μ-η(2) :η(1) :η(1) -3-{tBuNCH2 }Ind)Yb(thf)(CH2 SiMe3 )]2 (major) and cis-[(μ-η(2) :η(1) :η(1) -3-{tBuNCH2 }Ind)Yb(thf)(CH2 SiMe3 )]2 (minor) complexes. The catalytic activities of these dinuclear rare-earth metal alkyl complexes for isoprene polymerization were investigated; the yttrium and dysprosium complexes exhibited high catalytic activities and high regio- and stereoselectivities for isoprene 1,4-cis-polymerization. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Deformation, warming and softening of Greenland’s ice by refreezing meltwater

NASA Astrophysics Data System (ADS)

Bell, Robin E.; Tinto, Kirsteen; Das, Indrani; Wolovick, Michael; Chu, Winnie; Creyts, Timothy T.; Frearson, Nicholas; Abdi, Abdulhakim; Paden, John D.

2014-07-01

Meltwater beneath the large ice sheets can influence ice flow by lubrication at the base or by softening when meltwater refreezes to form relatively warm ice. Refreezing has produced large basal ice units in East Antarctica. Bubble-free basal ice units also outcrop at the edge of the Greenland ice sheet, but the extent of refreezing and its influence on Greenland’s ice flow dynamics are unknown. Here we demonstrate that refreezing of meltwater produces distinct basal ice units throughout northern Greenland with thicknesses of up to 1,100 m. We compare airborne gravity data with modelled gravity anomalies to show that these basal units are ice. Using radar data we determine the extent of the units, which significantly disrupt the overlying ice sheet stratigraphy. The units consist of refrozen basal water commonly surrounded by heavily deformed meteoric ice derived from snowfall. We map these units along the ice sheet margins where surface melt is the largest source of water, as well as in the interior where basal melting is the only source of water. Beneath Petermann Glacier, basal units coincide with the onset of fast flow and channels in the floating ice tongue. We suggest that refreezing of meltwater and the resulting deformation of the surrounding basal ice warms the Greenland ice sheet, modifying the temperature structure of the ice column and influencing ice flow and grounding line melting.

On the inversion of the 1 Bu and 2 Ag electronic states in α,ω-diphenylpolyenes

NASA Astrophysics Data System (ADS)

Catalán, J.

2003-07-01

An alternative model to that of the inversion of the states 1Bu and 2Ag is proposed for interpreting the photophysics of the α,ω-diphenylpolyenes. This model is based upon the existence of two chemical structures with Bu symmetry, which may be ascribed to the same excited electronic state 1Bu. One of the two chemical structures corresponds to the Franck-Condon structure with conjugated single and double bonds for the polyene chain, and another consists of a nearly equivalent series of partial double bonds along the polyene chain. The latter relaxed structure is consistent with the observation of high torsional energy barriers and low photoisomerization quantum yields for diphenylhexatriene in the singlet excited state manifold. Interestingly, such a simple quantum model as that of the particle in a one-dimensional box provides quite an accurate description of the absorption spectroscopic properties of these major compounds. This is partly the result of the most stable structures for these compounds being of the all-trans type; such structures increase in length as additional ethylene units are added, which makes them very similar to a one-dimensional box becoming increasingly longer.

Synthesis and reactions of nickel and palladium carbon-bound enolate complexes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burkhardt, E.R.; Bergman, R.G.; Heathcock, C.H.

1990-01-01

Nickel and palladium carbon-bound enolates of the general formula {eta}{sup 5}-C{sub 5}R{sub 5}(Ph{sub 3}P)MCHR{prime}COR{double prime} (R = H, CH{sub 3}; R{prime} = H, CH{sub 3}; R{double prime} = t-Bu, Ph, O-t-Bu) were prepared. Cp{sup *}(Ph{sub 3}P)NiCH{sub 2}CO{sub 2}-t-Bu (1e) was characterized by X-ray diffraction. Compound 1e crystallizes in the monoclinic space group P2{sub 1}/n with unit-cell dimensions a = 13.6110 (20) {angstrom}, b = 12.7454 (13) {angstrom}, c = 17.8571 (23) {angstrom}, {beta} = 105.544 (11){degree}, Z = 4, observed data 4,091, R = 4.53%, and R{sub w} = 4.19%. Reactions of these nickel and palladium enolates with aldehydes andmore » other electrophilic reagents were examined. The nickel ketone enolates were shown to react with 2 equiv of benzaldehyde to deliver products resulting from a Tischtschenko-type oxidation/reduction process. Cp(Ph{sub 3}P)NiCH{sub 2}CO-t-Bu reacts with phosphines (L) to yield paramagnetic nickel(I) complexes of general formula Cp(L){sub 2}Ni.« less

Application of a macrocyclic compound, bambus[6]uril, in tailor-made liquid membranes for highly selective electromembrane extractions of inorganic anions.

PubMed

Šlampová, Andrea; Šindelář, Vladimír; Kubáň, Pavel

2017-01-15

A tailor-made liquid membrane consisting of a resistive organic solvent (nitrobenzene, NB) and a highly selective non-ionic macrocyclic compound (bambus[6]uril, BU6) was employed for electromembrane extraction (EME) of inorganic anions. BU6 facilitates strong host-guest interactions of its internal cavity with selected inorganic anions only and its presence in the liquid membrane ensured excellent selectivity of the EME process. EME transfers were directly related to association constants between BU6 and inorganic anions and nearly absolute selectivity was achieved for EMEs of iodide, bromide and perchlorate. Major inorganic anions (chloride, nitrate, sulphate and carbonate), which exhibit low interactions with BU6 cavity, were efficiently eliminated from the EME transfer. No interferences were observed for EMEs of target analytes from samples containing up to 100.000-fold higher concentrations of the major anions. Addition of species-specific macrocyclic modifiers to free and supported liquid membranes might thus open new directions in fine-tuning of EME selectivity. At optimized EME conditions (polypropylene hollow fiber impregnated with NB + 3% (w/w) BU6, extraction voltage 25 V, extraction time 15 min, deionized water as acceptor solution) perchlorate was selectively extracted from tap water at concentrations below the guideline value recommended by United States Environmental Protection Agency. Excellent selectivity of the tailor-made liquid membrane was further demonstrated by EME of bromide from sea water. Copyright © 2016 Elsevier B.V. All rights reserved.

Presence and absence of electronic mixing in shorter-chain and longer-chain carotenoids: Assignment of the symmetries of 1Bu- and 3Ag- states located just below the 1Bu+ state

NASA Astrophysics Data System (ADS)

Sutresno, Adita; Kakitani, Yoshinori; Zuo, Ping; Li, Chunyong; Koyama, Yasushi; Nagae, Hiroyoshi

2007-10-01

In spheroidene (having the number of conjugated double bonds n = 10), stimulated emission was observed from the mixed vibronic levels of 1Bu+(0)+1Bu-(2) and 1Bu+(1)+1Bu-(3), whereas in lycopene, anhydrorhodovibrin and spirilloxanthin ( n = 11-13), stimulated emission, from the pure vibronic levels of 1Bu+(0) and 1Bu+(1). Thus, the 1Bu+ state can mix with the 1Bu- state but not with the 3Ag- state, both being located just below the 1Bu+ state. The presence and absence of the mixing of the neighboring diabatic states support the symmetries of the next low-lying 1Bu- and 3Ag- states.

A Mn(III) triplesalen-based 1D pearl necklace: exchange interactions and zero-field splittings in a C3-symmetric Mn(III)6 complex.

PubMed

Glaser, Thorsten; Heidemeier, Maik; Theil, Hubert; Stammler, Anja; Bögge, Hartmut; Schnack, Jürgen

2010-01-07

The reaction of the tert-butyl-substituted triplesalen ligand H(6)talen(t-Bu(2)) with 2.8 equivalents of Mn(OAc)(2) x 4 H(2)O in MeOH in the presence of NaBPh(4) results in the formation of the one-dimensional (1D) coordination polymer {[{(talen(t-Bu(2)))Mn(3)(MeOH)}(2)(mu(2)-OAc)(3)](mu(2)-OAc)}(n)(BPh(4))(2n) ({[Mn(III)(6)](OAc)}(n)(BPh(4))(2n)) which has been characterized by FTIR, elemental analysis, ESI-MS, single-crystal X-ray diffraction and magnetic measurements. The triplesalen ligand (talen(t-Bu(2)))(6-) provides three salen-like coordination compartments bridged in a meta-phenylene arrangement by a phloroglucinol backbone resulting in the trinuclear Mn(III) base unit {(talen(t-Bu(2)))Mn(3)}(3+). Two of these base units are bridged by three inner acetate ligands giving rise to the hexanuclear complex [{(talen(t-Bu(2)))Mn(3)(MeOH)}(2)(mu(2)-OAc)(3)](3+) ([Mn(III)(6)](3+)). These complexes are bridged by a single external acetate to form a 1D chain as pearls in a pearl necklace. Variable temperature-variable field and mu(eff)vs. T magnetic data have been analyzed in detail by full-matrix diagonalization of the appropriate spin-Hamiltonian consisting of isotropic exchange, zero-field splitting, and Zeeman interaction taking into account the relative orientation of the D-tensors. Satisfactory reproduction of the experimental data have been obtained for parameters sets J(1) = -(0.60 +/- 0.15) cm(-1), J(2) = -(1.05 +/- 0.15) cm(-1), and D(Mn) = -(3.0 +/- 0.7) cm(-1) with J(1) describing the exchange through the phloroglucinol backbone and J(2) describing the exchange through the inner acetates. The non-necessity to incorporate the bridging outer acetates correlates with the longer Mn-O bonds. The experimental data can neither be analyzed without incorporating zero-field splitting nor by the application of a single effective spin ground state.

New superhindered polydentate polyphosphine ligands P(CH2CH2P(t)Bu2)3, PhP(CH2CH2P(t)Bu2)2, P(CH2CH2CH2P(t)Bu2)3, and their ruthenium(II) chloride complexes.

PubMed

Gilbert-Wilson, Ryan; Field, Leslie D; Bhadbhade, Mohan M

2012-03-05

The synthesis and characterization of the extremely hindered phosphine ligands, P(CH(2)CH(2)P(t)Bu(2))(3) (P(2)P(3)(tBu), 1), PhP(CH(2)CH(2)P(t)Bu(2))(2) (PhP(2)P(2)(tBu), 2), and P(CH(2)CH(2)CH(2)P(t)Bu(2))(3) (P(3)P(3)(tBu), 3) are reported, along with the synthesis and characterization of ruthenium chloro complexes RuCl(2)(P(2)P(3)(tBu)) (4), RuCl(2)(PhP(2)P(2)(tBu)) (5), and RuCl(2)(P(3)P(3)(tBu)) (6). The bulky P(2)P(3)(tBu) (1) and P(3)P(3)(tBu) (3) ligands are the most sterically encumbered PP(3)-type ligands so far synthesized, and in all cases, only three phosphorus donors are able to bind to the metal center. Complexes RuCl(2)(PhP(2)P(2)(tBu)) (5) and RuCl(2)(P(3)P(3)(tBu)) (6) were characterized by crystallography. Low temperature solution and solid state (31)P{(1)H} NMR were used to demonstrate that the structure of RuCl(2)(P(2)P(3)(tBu)) (4) is probably analogous to that of RuCl(2)(PhP(2)P(2)(tBu)) (5) which had been structurally characterized.

47 CFR 73.509 - Prohibited overlap.

Code of Federal Regulations, 2012 CFR

2012-10-01

... mV/m (60 dBu)0.1 mV/m (40 dBu) 200 kHz 0.5 mV/m (54 dBu)1 mV/m (60 dBu)1 1 mV/m (60 dBu)0.5 mV/m (54...-channel 0.1 mV/m (40 dBu) 1 mV/m (60 dBu). 200 kHz 0.5 mV/m (54 dBu) 1 mV/m (60 dBu). 400 kHz 10 mV/m (80... Commission and operating in the reserved band (Channels 200-220, inclusive) as set forth below: Frequency...

47 CFR 73.509 - Prohibited overlap.

Code of Federal Regulations, 2013 CFR

2013-10-01

... mV/m (60 dBu)0.1 mV/m (40 dBu) 200 kHz 0.5 mV/m (54 dBu)1 mV/m (60 dBu)1 1 mV/m (60 dBu)0.5 mV/m (54...-channel 0.1 mV/m (40 dBu) 1 mV/m (60 dBu). 200 kHz 0.5 mV/m (54 dBu) 1 mV/m (60 dBu). 400 kHz 10 mV/m (80... Commission and operating in the reserved band (Channels 200-220, inclusive) as set forth below: Frequency...

47 CFR 73.509 - Prohibited overlap.

Code of Federal Regulations, 2014 CFR

2014-10-01

... mV/m (60 dBu)0.1 mV/m (40 dBu) 200 kHz 0.5 mV/m (54 dBu)1 mV/m (60 dBu)1 1 mV/m (60 dBu)0.5 mV/m (54...-channel 0.1 mV/m (40 dBu) 1 mV/m (60 dBu). 200 kHz 0.5 mV/m (54 dBu) 1 mV/m (60 dBu). 400 kHz 10 mV/m (80... Commission and operating in the reserved band (Channels 200-220, inclusive) as set forth below: Frequency...

Optic nerve head axonal transport in rabbits with hereditary glaucoma.

PubMed

Bunt-Milam, A H; Dennis, M B; Bensinger, R E

1987-04-01

Rabbits with hereditary glaucoma develop ocular changes that resemble human congenital glaucoma and buphthalmia. The inheritance is autosomal recessive (bu). Previous research was performed primarily on albino bu/bu rabbits that were unhealthy and bred poorly. We have bred pigmented bu/bu rabbits to determine if this would improve hardiness and provide a better model for the disease in humans. First-generation offspring from matings of bu/bu albino with bu/bu pigmented rabbits were all affected, indicating that the bu gene is found at the same locus in both strains. The pigmented bu/bu offspring had a high degree of mortality, as reported previously for albino bu/bu rabbits. Newborn bu/bu rabbits initially had normal intraocular pressure (IOP; 15-23 mmHg); after 1- to 3 months, the IOP increased to 26-48 mmHg. The eyes became buphthalmic and the IOP returned to normal or sub-normal levels after 6-10 months. Since the lamina cribrosa is absent or poorly formed in the rabbit optic nerve head (ONH), this model was used to test the role of mechanical factors in the etiology of ONH pathology caused by increased IOP. Orthograde axonal transport was evaluated in both eyes from eight normal and 24 bu/bu rabbits of different ages, using intravitreal injections of [3H]leucine to mark orthograde axonal transport, followed by light- and electron-microscopic radioautography of the ONHs and superior colliculi. Normal rabbits of all ages showed no blockage of axonal transport in the ONH. All optic axons from young bu/bu rabbits with normal IOP and most axons from older buphthalmic rabbits that previously had elevated IOP were normal morphologically. Small zones of transport blockage occurred in bu/bu eyes while IOP was elevated; most affected axons lay immediately adjacent to ONH connective tissue beams that radiate outward from the central retinal vessels to the optic-nerve sheath. Thus, the rabbit, which lacks a true lamina cribrosa, does not show marked blockage of axonal transport as occurs in the LS of the monkey and cat ONH when IOP is elevated acutely. This anatomic difference appears to be protective against axonal damage, since bu/bu rabbits with chronic IOP elevation did not show significant loss of optic axons. These results are consistent with the proposed 'mechanical' theory of ONH damage resulting from increased IOP. Electron-microscopic radioautography revealed that chronically elevated IOP in bu/bu rabbits, which caused small foci of blocked ONH axonal transport against ONH beams, also caused degeneration of a few optic nerve terminals in the superior colliculi as the disease progressed.(ABSTRACT TRUNCATED AT 400 WORDS)

Upregulation of Mouse Genes in HSV-1 Latent TG after Butyrate Treatment Implicates the Multiple Roles of the LAT-ICP0 Locus

PubMed Central

Clement, Christian; Bhattacharjee, Partha S.; Kumar, Manish; Foster, Timothy P.; Thompson, Hilary W.

2011-01-01

Purpose. To determine host response by gene expression in HSV-1 latent trigeminal ganglia (TG) after sodium butyrate (NaBu) treatment. Methods. Corneas of 6-week-old female BALB/c mice were scarified and inoculated with HSV-1 17Syn+ (high phenotypic reactivator) or its mutant 17ΔPst(LAT−) (low phenotypic reactivator) at 104 plaque-forming units/eye. NaBu-induced viral reactivation was by intraperitoneal (IP) administration at postinfection (PI) day 28, followed by euthanasia after 1 hour. NaBu-treated, uninfected mice served as the control. The resultant labeled cRNA from TG isolated total RNA was hybridized to gene microarray chips containing 14,000 mouse genes. Quantitative real-time PCR was performed to confirm gene expression. Results. Differential induction of gene expression between 17Syn+ and its mutant 17ΔPst(LAT−) was designated as NaBu-induced gene expression and yielded significant upregulation of 2- to 16-fold of 0.4% (56/14,000) host genes probed, comprising mainly nucleosome assembly and binding, central nervous system structural activity, hormonal activity, and signaling activity. Approximately 0.2% (24/14,000) of the host genes, mainly of the same functional categories were downregulated 3- to 11-fold. Immune activity was minor in comparison to our reports on gene expression during latency and heat stress induction. Euchromatin analysis revealed that the LAT-ICP0 locus is amenable to the effects of NaBu. Histone activity was detected by early transcription of histone cluster 2 H2be (Hist2h2be). Conclusions. NaBu-induced reactivation of HSV-1 is twofold: drug action involving significant moderation of specific host epigenetic changes and failure to elicit or suppress immune activity at the early time point of 1 hour. PMID:20881297

Glut-1 translocation in FRTL-5 thyroid cells: role of phosphatidylinositol 3-kinase and N-glycosylation.

PubMed

Samih, N; Hovsepian, S; Aouani, A; Lombardo, D; Fayet, G

2000-11-01

It was previously demonstrated that insulin or TSH treatment of FRTL-5 cells resulted in an elevation of glucose transport and in an increase of cell surface expression of the glucose transporter Glut-1. However, the signaling mechanisms leading to the insulin or TSH-induced increase in the cell surface expression of Glut-1 were not investigated. In the present study, we demonstrated that wortmannin and LY294002, two specific inhibitors of phosphatidylinositol 3-kinase (PI3-kinase), interfere both in the signaling pathways of insulin and TSH leading to glucose consumption enhancement and Glut-1 translocation. Two hours after insulin treatment, TSH or cAMP analog (Bu)2cAMP stimulation, glucose transport was increased and most of the intracellular Glut-1 pool was translocated to plasma membranes. Wortmannin or LY294002 blocked the insulin, (Bu)2cAMP, and the TSH-induced translocation of Glut-1. Wortmannin or LY294002 alone did not alter the basal ratio between intracellular and cell surface Glut-1 molecules. These results suggest that in FRTL-5 cells wortmannin and LY294002 inhibited the insulin, (Bu)2cAMP and TSH events leading to Glut-1 translocation from an intracellular compartment to the plasma membrane. Likewise, (Bu)2cAMP effects on glucose transport and Glut-1 translocation to plasma membrane were repressed by PI3-kinase inhibitors but not by the protein kinase A (PKA) inhibitor H89. We suggest that (Bu)2cAMP stimulates Glut-1 translocation to plasma membrane through PI3-kinase-dependent and PKA-independent signaling pathways. To further elucidate mechanisms that regulate the translocation of Glut-1 to cell membrane, we extended this study to the role played by the N-glycosylation in the translocation and in the biological activity of Glut-1 in FRTL-5 cells. For this purpose we used tunicamycin, an inhibitor of the N-glycosylation. Our experiments with tunicamycin clearly showed that both the glycosylated and unglycosylated forms of the transporter reached the cell surface. Likewise, a decrease in glucose consumption (-50%) after treatment of cells with tunicamycin was accompanied by a decrease (-70% vs. control) in the membrane expression of a 50-kDa form of Glut-1 and an increase in its unglycosylated 41-kDa form. These results suggest that carbohydrate moiety is essential for the biological activity of glucose transport but is not required for the translocation of Glut-1 from the intracellular membrane pool to the plasma membrane.

Reaction of the thermo-labile triazenide Na[tBu3SiNNNSiMe3] with CO2: formation of the imido carbonate (tBu3SiO)(Me3SiO)C[double bond, length as m-dash]N-SitBu3 and carbamine acid (tBu3SiO)CONH2.

PubMed

Lerner, H-W; Bolte, M; Wagner, M

2017-07-11

The thermo-labile triazenide Na[tBu 3 SiNNNSiMe 3 ] was prepared by the reaction of Me 3 SiN 3 with Na(thf) 2 [SitBu 3 ] in pentane at -78 °C. Treatment of Na[tBu 3 SiNNNSiMe 3 ] with an excess of carbon dioxide in pentane at -78 °C yielded the imido carbonate (tBu 3 SiO)(Me 3 SiO)C[double bond, length as m-dash]N-SitBu 3 and the carbamine acid (tBu 3 SiO)CONH 2 along with other products. From the reaction solution we could isolate the imido carbonate (tBu 3 SiO)(Me 3 SiO)C[double bond, length as m-dash]N-SitBu 3 and carbamine acid (tBu 3 SiO)CONH 2 . At first single crystals of the carbamine acid (tBu 3 SiO)CONH 2 (triclinic, space group P1[combining macron]) were grown from this solution at room temperature. A second crop of crystals were obtained by concentrating the solution. The second charge consisted of the imido carbonate (tBu 3 SiO)(Me 3 SiO)C[double bond, length as m-dash]N-SitBu 3 (monoclinic, space group P2 1 /n).

Reactivity of Silanes with ( tBuPONOP)Ruthenium Dichloride: Facile Synthesis of Chloro-Silyl Ruthenium Compounds and Formic Acid Decomposition

DOE PAGES

Anderson, Nickolas H.; Boncella, James M.; Tondreau, Aaron M.

2017-08-15

The coordination of tBuPONOP ( tBuPONOP=2,6-bis(ditert-butylphosphinito)pyridine) to different ruthenium starting materials, to generate ( tBuPONOP)RuCl 2, was investigated in this paper. The resultant ( tBuPONOP)RuCl 2 reactivity with three different silanes was then investigated and contrasted dramatically with the reactivity of ( iPrPONOP)RuCl 2(DMSO) ( iPrPONOP=2,6-bis(diisopropylphosphinito)pyridine) with the same silanes. The 16-electron species ( tBuPONOP)Ru(H)Cl was produced from the reaction of triethylsilane with ( tBuPONOP)RuCl 2. Reactions of ( tBuPONOP)RuCl 2 with both phenylsilane or diphenylsilane afforded the 16-electron hydrido-silyl species ( tBuPONOP)Ru(H)(PhSiCl 2) and ( tBuPONOP)Ru(H)(Ph 2SiCl), respectively. Reactions of all three of these complexes with silver triflate affordedmore » the simple salt metathesis products of ( tBuPONOP)Ru(H)(OTf), ( tBuPONOP)Ru(H)(PhSiCl(OTf)), and ( tBuPONOP)Ru(H)(Ph 2Si(OTf)). Formic acid dehydrogenation was performed in the presence of triethylamine (TEA), and each species proved competent for gas-pressure generation of CO 2 and H 2. Finally, the hydride species ( tBuPONOP)Ru(H)Cl, ( tBuPONOP)Ru(H)(OTf), and ( tBuPONOP)Ru(H)(PhSiCl 2) exhibited faster catalytic activity than the other compounds tested.« less

Seismic stratigraphy of sedimentary cover in Amerasian Basin based on the results of Russian High Arctic expeditions

NASA Astrophysics Data System (ADS)

Poselov, Viktor; Kireev, Artem; Smirnov, Oleg; Butsenko, Viktor; Zholondz, Sergey; Savin, Vasily

2016-04-01

Massive amount of multichannel seismic (MCS) data were obtained by Russian High Arct ic expeditions "Arctica-2011", "Acrtica-2012" and "Arctica-2014". More than 40 MCS lines are located in the Amerasian basin and help to substantiate the seismic stratigraphy model of its sedimentary cover. The proposed seismic stratigraphy model was successively determined for the Cenozoic and pre-Cenozoic parts of the sedimentary section and was based on correlation of the Russian MCS data and seismic data documented by boreholes. Cenozoic part of the sedimentary cover is based on correlation of the Russian MCS data and AWI91090 section calibrated by ACEX-2004 boreholes on the Lomonosov Ridge. Two major unconformities are traced. The upper regional unconformity (RU) is associated with a major pre-Miocene hiatus. Another major hiatus is recorded in the borehole section between the Campanian and the Upper Paleocene units. It is recognized as the post-Campanian unconformity (pCU) in the seismic sections. Formation of the regional unconformities is associated with a fundamental change in depositional environment. Formation of RU was initiated by opening of the Fram Strait gateway at the Paleogene/Neogene boundary. Post-Campanian unconformity is linked with the initial stage of the Eurasian Basin opening between the Cretaceous and the Paleogene. Cenozoic sedimentary units are continuously traced from the East-Siberian and Chukchi sea shelves across the transit zone to the Amerasian basin. Paleogene unit (between pCU and RU) is formed under the neritic depositional environment and it is characterized by an extremely small thickness on the Lomonosov Ridge (less than 200 m), on the Mendeleev Rise and in the Podvodnikov Basin (not more than 300-400 m). Neogene unit (above RU) consists of hemipelagic deposits and occupies the essential part of thickness of the Cenozoic section in Podvodnikov and Makarov Basins. Interval velocities in the Paleogene unit vary within 2.8-3.2 km/s, in the Neogene unit they vary within 1.8-2.7 km/s. Pre-Cenozoic part of the sedimentary cover is based on tracing major unconformities from boreholes on the Chukchi shelf (Crackerjack, Klondike, Popcorn) to the North-Chuckchi Trough and further to the Mendeleev Rise as well as to the Vilkitsky Trough and the adjacent Podvodnikov Basin. Three regional unconformities are correlated: Jurassic (JU - top of the Upper Ellesmerian unit), Lower Cretaceous (LCU) and Brookian (BU - base of the Lower Brookian unit). Above the acoustic basement the pre-Cenozoic section is mainly represented by terrigenous units. Two major unconformities: RU and pCU are allocated on all MCS lines intersecting the Mendeleev Rise along its entire extent. BU is traced nearly everywhere along the rise excepting certain acoustic basement highs. All unconformities are also traced from the Mendeleev Rise to the continental structure of the Chuckchi Borderland. Sedimentary sequence between pCU and JU which underlies deposits of the Upper Ellesmerian unit is recorded as a synrift unit of the entire area of the Podvodnikov Basin. MCS data show a natural prolongation of the sedimentary cover from the shelf to the Podvodnikov Basin without any breaks and tectonic movements. Interval velocities in the Upper Cretaceous unit (between pCU and BU) vary within 3.2-3.9 km/s, in the pre-Upper Cretaceous units (between BU and the acoustic basement) vary within 4.1-4.8 km/s.

Synthesis and structure of the extended phosphazane ligand [(1,4-C6H4){N(μ-PN(t)Bu)2N(t)Bu}2](4).

PubMed

Sevilla, Raquel; Less, Robert J; García-Rodríguez, Raúl; Bond, Andrew D; Wright, Dominic S

2016-02-07

The reaction of the phenylene-bridged precursor (1,4-C6H4)[N(PCl2)2]2 with (t)BuNH2 in the presence of Et3N gives the new ligand precursor (1,4-C6H4)[N(μ-N(t)Bu)2(PNH(t)Bu)2]2, deprotonation of which with Bu2Mg gives the novel tetraanion [(1,4-C6H4){N(μ-N(t)Bu)2(PN(t)Bu)2}2](4-).

Germylenes and stannylenes stabilized within N2PE rings (E = Ge or Sn): combined experimental and theoretical study.

PubMed

Vrána, Jan; Ketkov, Sergey; Jambor, Roman; Růžička, Aleš; Lyčka, Antonín; Dostál, Libor

2016-06-21

The deprotonation of aminophosphanes PhP(NHR)2 (R = t-Bu or Dip; Dip = 2,6-i-Pr2C6H3) and t-BuP(NHDip)2 using n-BuLi gave, depending on the stoichiometry, both the dilithium compounds {[PhP(Nt-Bu)2]Li2}2 (), [PhP(Nt-Bu)(NDip)]Li2·(Et2O) (), [t-BuP(NDip)2]Li2·(Et2O)2 () and [t-BuP(NDip)2]Li2·(tmeda)2 (), and the monolithium compounds [PhP(NHt-Bu)(NR)]Li·(tmeda) (R = t-Bu , Dip ) and [t-BuP(NHDip)(NDip)]Li·(tmeda) (). Treatment of , and with GeCl2·dioxane or SnCl2 in a 1 : 1 stoichiometric ratio gave the corresponding tetrylenes [PhP(Nt-Bu)2]E (E = Ge , Sn ), [PhP(Nt-Bu)(NDip)]Ge () and [t-BuP(NDip)2]E (E = Ge , Sn ). The heteroleptic germylene [Ph(H)P(Nt-Bu)2]GeCl () was obtained by the reaction of the monolithium compound [PhP(NHt-Bu)(Nt-Bu)]Li·(tmeda) () with GeCl2·dioxane in a 1 : 1 stoichiometric ratio, as a result of a spontaneous NH → PH tautomeric shift in the ligand backbone. In contrast, an analogous reaction with SnCl2 produced only stannylene along with the PhP(NHt-Bu)2 starting material, suggesting scrambling of the ligands rather than a NH → PH tautomeric shift. Finally, heating in solution led to P-C bond cleavage and formation of the bis(imino)phosphide [DipNPNDip]Li·(tmeda) (). The reaction of with GeCl2·dioxane, SnCl2 or PbCl2 in a 2 : 1 stoichiometric ratio yielded the unprecedented tetrylenes [DipNPNDip]2E (E = Ge , Sn and Pb ), in which the tetrylene center is incorporated within two N2PE rings. Treatment of the monolithium compound with n-BuLi and K (or KC8) gave [t-BuNPNt-Bu]Li·(tmeda) () and{[t-BuNPNt-Bu]K(tmeda)}2 (), respectively. In contrast to the reaction with , similar reactions of with GeCl2·dioxane and SnCl2 resulted in the known compounds cis-[P(μ-Nt-Bu)2P(t-BuN)2]E (E = Ge, Sn); evidently the t-Bu groups do not provide sufficient steric shielding to protect the bis(imino)phosphide backbone as in the case of . The bonding situation in a set of selected compounds (, ) has been subjected to a theoretical survey with particular emphasis on the nature of the bonding between the ligand and the central metal and the bonding within the NPN core of the ligand, showing significant differences among the studied complexes.

New metal-organic polygons involving MM quadruple bonds: M8(O2CtBu)4(mu-SC4H2-3,4-{CO2}2)6 (M=Mo, W).

PubMed

Byrnes, Matthew J; Chisholm, Malcolm H; Patmore, Nathan J

2005-12-12

The reactions between M2(O2CtBu)4, where M=Mo or W, and thienyl-3,4-dicarboxylic acid (0.5-1.5 equiv) in toluene proceed via a series of detectable intermediates to the compounds M8(O2CtBu)4(mu-SC4H2-3,4-{CO2}2)6, which are isolated as air-sensitive yellow (M=Mo) or red (M=W) powders and show parent molecular ions in their mass spectra (MALDI). The structure of the molybdenum complex was determined by single-crystal X-ray crystallography and shown to contain an unusual M8 polygon involving four Mo2 quadruply bonded units linked via the agency of the six 3,4-thienylcarboxylate groups. The structure has crystallographically imposed S4 symmetry and may be described in terms of a highly distorted tetrahedron of Mo2 units or a bisphenoid in which two Mo2 units are linked by a thienyldicarboxylate such that intramolecular Mo2...O bonding is present, while the other thienylcarboxylate bridges merely serve to link these two [Mo2]...[Mo2] units together. The color of the compounds arises from intense M2 delta-to-thienyl pi transitions and, in THF, the complexes are redox-active and show four successive quasi-reversible oxidation waves. The [M8]+ radical cations, generated by one-electron oxidation with AgPF6, are shown to be valence-trapped (class II) by UV-vis-near-IR and electron paramagnetic resonance spectroscopy. These results are supported by the electronic structure calculations on model compounds M8(O2CH)4(mu-SC4H2-3,4-{CO}2)6 employing density functional theory that reveal only a small splitting of the M2 delta manifold via mixing with the 3,4-thienylcarboxylate pi system.

The inverse sandwich complex [(K(18-crown-6))2Cp][CpFe(CO)2]--unpredictable redox reactions of [CpFe(CO)2]I with the silanides Na[SiRtBu2] (R = Me, tBu) and the isoelectronic phosphanyl borohydride K[PtBu2BH3].

PubMed

Sänger, Inge; Kückmann, Theresa I; Dornhaus, Franz; Bolte, Michael; Wagner, Matthias; Lerner, Hans-Wolfram

2012-06-14

The dimeric iron carbonyl [CpFe(CO)(2)](2) and the iodosilanes tBu(2)RSiI were obtained from the reaction of [CpFe(CO)(2)]I with the silanides Na[SiRtBu(2)] (R = Me, tBu) in THF. By the reactions of [CpFe(CO)(2)]I and Na[SiRtBu(2)] (R = Me, tBu) the disilanes tBu(2)RSiSiRtBu(2) (R = Me, tBu) were additionally formed using more than one equivalent of the silanide. In this context it should be noted that reduction of [CpFe(CO)(2)](2) with Na[SitBu(3)] gives the disilanes tBu(3)SiSitBu(3) along with the sodium ferrate [(Na(18-crown-6))(2)Cp][CpFe(CO)(2)]. The potassium analogue [(K(18-crown-6))(2)Cp][CpFe(CO)(2)] (orthorhombic, space group Pmc2(1)), however, could be isolated as a minor product from the reaction of [CpFe(CO)(2)]I with [K(18-crown-6)][PtBu(2)BH(3)]. The reaction of [CpFe(CO)(2)](2) with the potassium benzophenone ketyl radical and subsequent treatment with 18-crown-6 yielded the ferrate [K(18-crown-6)][CpFe(CO)(2)] in THF at room temperature. The crown ether complex [K(18-crown-6)][CpFe(CO)(2)] was analyzed using X-ray crystallography (orthorhombic, space group Pna2(1)) and its thermal behaviour was investigated.

Efficient near-infrared emission of π-extended cyclometalated iridium complexes based on pyrene in solution-processed polymer light-emitting diode

NASA Astrophysics Data System (ADS)

Liu, Yu; Hao, Zhaoran; Meng, Fanyuan; Wang, Pu; Yang, Liang; Wang, Yafei; Pei, Yong; Su, Shijian

2018-05-01

A novel iridium complex grafting hole-transporting triphenylamine (TPA) unit onto cyclometalated ligand, namely t-BuPyrPyTPA)2Ir(acac), was successfully synthesized and characterized. The photophysical, electrochemical and DFT/TD-DFT calculation, as well as electroluminescence properties of this iridium complex were fully investigated. Meanwhile, the PLEDs employing (t-BuPyrPyTPA)2Ir(acac) as dopant presented stable NIR emission peaked at 697 nm and a shoulder at 764 nm with a highest external quantum efficiency (EQE) of 0.56% at 4 wt% dopant concentration. These results demonstrate that expanding the conjugation length of the ligand is an effective way to achieve NIR emission.

Nanofibers of fullerene C60 through interplay of ball-and-socket supermolecules.

PubMed

Hubble, Lee J; Raston, Colin L

2007-01-01

Mixing solutions of p-tBu-calix[5]arene and C(60) in toluene results in a 1:1 complex (C(60)) intersection(p-tBu-calix[5]arene), which precipitates as nanofibers. The principle structural unit is based on a host-guest ball-and-socket nanostructure of the two components, with an extended structure comprising zigzag/helical arrays of fullerenes (powder X-ray diffraction data coupled with molecular modeling). Under argon at temperatures above 309 degrees C, the fibers undergo selective volatilization of the calixarenes to afford C(60)-core nanostructures encapsulated in a graphitic material sheath, which exhibits a dramatic increase in surface area. Above 650 degrees C the material exhibits an ohmic conductance response, due to the encapsulation process.

Two Blades-Up Runs Using the JetStream Navitus Atherectomy Device Achieve Optimal Tissue Debulking of Nonocclusive In-Stent Restenosis: Observations From a Porcine Stent/Balloon Injury Model.

PubMed

Shammas, Nicolas W; Aasen, Nicole; Bailey, Lynn; Budrewicz, Jay; Farago, Trent; Jarvis, Gary

2015-08-01

To determine the number of runs with blades up (BU) using the JetStream Navitus to achieving optimal debulking in a porcine model of femoropopliteal artery in-stent restenosis (ISR). In this porcine model, 8 limbs were implanted with overlapping nitinol self-expanding stents. ISR was treated initially with 2 blades-down (BD) runs followed by 4 BU runs (BU1 to BU4). Quantitative vascular angiography (QVA) was performed at baseline, after 2 BD runs, and after each BU run. Plaque surface area and percent stenosis within the treated stented segment were measured. Intravascular ultrasound (IVUS) was used to measure minimum lumen area (MLA) and determine IVUS-derived plaque surface area. QVA showed that plaque surface area was significantly reduced between baseline (83.9%±14.8%) and 2 BD (67.7%±17.0%, p=0.005) and BU1 (55.4%±9.0%, p=0.005) runs, and between BU1 and BU2 runs (50.7%±9.7%, p<0.05). Percent stenosis behaved similarly with no further reduction after BU2. There were no further reductions in plaque surface area or percent stenosis with BU 3 and 4 runs (p=0.10). Similarly, IVUS (24 lesions) confirmed optimal results with BU2 runs and no additional gain in MLA or reduction in plaque surface area with BU3 and 4. IVUS confirmed no orbital cutting with JetStream Navitus. There were no stent strut discontinuities on high-resolution radiographs following atherectomy. JetStream Navitus achieved optimal tissue debulking after 2 BD and 2 BU runs with no further statistical gain in debulking after the BU2 run. Operators treating ISR with JetStream Navitus may be advised to limit their debulking to 2 BD and 2 BU runs to achieve optimal debulking. © The Author(s) 2015.

Can BuCyE conditioning regimen be an alternative treatment to BEAM at autologous transplantation in malignant lymphoma patients?: a single center experience

PubMed Central

Berber, Ilhami; Erkurt, Mehmet Ali; Nizam, Ilknur; Koroglu, Mustafa; Kaya, Emin; Kuku, Irfan; Bag, Harika Gozukara

2015-01-01

High-dose chemotherapy (HDC) applied together with autologous stem cell transplantation (ASCT) is a commonly used treatment modality in patients with malignant lymphoma. At present, there is a limited number of studies which compare toxicity and efficacy of various high-dose regimens applied in the treatment of malignant lymphoma. For this reason, the aim of this study was to investigate the efficacy and toxicity of BuCyE (busulfan, cyclophosphamide and etoposide) and BEAM (carmustine, etoposide, cytarabine and melphalan) preparative regimens in the patients with malignant lymphoma scheduled for autologous stem cell transplantation. Between November, 2010 and April, 2015, 42 patients with relapsed or refractory malignant lymphoma who underwent autologous stem cell transplantation following BEAM (n=11) and BuCyE (n=31) preparative regimens were analyzed at Bone Marrow Transplantation Unit of TurgutOzal Medicine Center in Turkey. The groups were compared in terms of patient characteristics, hematopoietic engraftment time, toxicity profiles and survival. No significant differences were detected between the groups with regard to age, gender distribution, international prognostic index, ASCT indications, disease status at the time of ASCT and type of lymphoma (P>0.05). Median number of infused CD34+ cells/kg, neutrophil and platelet engraftment statuses of BuCyE and BEAM groups were found to be similar (P>0.05). More patients in BuCyE group developed mucositis and nausea, but this difference was not statistically significant (P>0.05). A similar statistically insignificant difference was seen in that infectious complications occurred more commonly in BEAM group (P>0.05). Overall survival and event-free survival rates were not significantly different between the groups (P>0.05). BuCyE is a conditioning regimen which can be effectively used as an alternative to BEAM in the patients with malignant lymphoma undergoing ASCT. Moreover, toxicity rates of both regimens are similar. In order to comprehend the effect of each HDC regimen, further evidence-based data obtained from the studies involving larger sample sizes are required. PMID:26629149

Can BuCyE conditioning regimen be an alternative treatment to BEAM at autologous transplantation in malignant lymphoma patients?: a single center experience.

PubMed

Berber, Ilhami; Erkurt, Mehmet Ali; Nizam, Ilknur; Koroglu, Mustafa; Kaya, Emin; Kuku, Irfan; Bag, Harika Gozukara

2015-01-01

High-dose chemotherapy (HDC) applied together with autologous stem cell transplantation (ASCT) is a commonly used treatment modality in patients with malignant lymphoma. At present, there is a limited number of studies which compare toxicity and efficacy of various high-dose regimens applied in the treatment of malignant lymphoma. For this reason, the aim of this study was to investigate the efficacy and toxicity of BuCyE (busulfan, cyclophosphamide and etoposide) and BEAM (carmustine, etoposide, cytarabine and melphalan) preparative regimens in the patients with malignant lymphoma scheduled for autologous stem cell transplantation. Between November, 2010 and April, 2015, 42 patients with relapsed or refractory malignant lymphoma who underwent autologous stem cell transplantation following BEAM (n=11) and BuCyE (n=31) preparative regimens were analyzed at Bone Marrow Transplantation Unit of TurgutOzal Medicine Center in Turkey. The groups were compared in terms of patient characteristics, hematopoietic engraftment time, toxicity profiles and survival. No significant differences were detected between the groups with regard to age, gender distribution, international prognostic index, ASCT indications, disease status at the time of ASCT and type of lymphoma (P>0.05). Median number of infused CD34+ cells/kg, neutrophil and platelet engraftment statuses of BuCyE and BEAM groups were found to be similar (P>0.05). More patients in BuCyE group developed mucositis and nausea, but this difference was not statistically significant (P>0.05). A similar statistically insignificant difference was seen in that infectious complications occurred more commonly in BEAM group (P>0.05). Overall survival and event-free survival rates were not significantly different between the groups (P>0.05). BuCyE is a conditioning regimen which can be effectively used as an alternative to BEAM in the patients with malignant lymphoma undergoing ASCT. Moreover, toxicity rates of both regimens are similar. In order to comprehend the effect of each HDC regimen, further evidence-based data obtained from the studies involving larger sample sizes are required.

A decade of evaluating the ecological effects of grass filter strips on channelized agricultural headwater streams

USDA-ARS?s Scientific Manuscript database

Grass filter strips are a widely used conservation practice in the Midwestern United States for reducing nutrient, pesticide, and sediment inputs into agricultural streams. Previous studies have documented the effectiveness of grass filter strips in reducing the input of agricultural pollutants, bu...

The Challenge of Drug Trafficking to Democratic Governance and Human Security in West Africa

DTIC Science & Technology

2013-05-01

Washing ton, DC, as the Director of the Office of Environmental Policy; as Economic Officer in the Bu- reau of Econom ic and Business Affairs... Colombian cartels established links with Mexican syndicates after the United States significantly choked off the old Ca- ribbean drug...transportation corridor and forced the Colombians to start moving their drug loads across the southwest border of the United States.48 Mexican DTOs, including

Evaluation of effects of busulfan and DMA on SOS in pediatric stem cell recipients.

PubMed

Kerl, Kornelius; Diestelhorst, Christian; Bartelink, Imke; Boelens, Jaap; Trame, Mirjam N; Boos, Joachim; Hempel, Georg

2014-02-01

Busulfan (Bu) is a DNA-alkylating agent used for myeloablative conditioning in stem cell transplantation in children and adults. While the use of intravenous rather than oral administration of Bu has reduced inter-individual variability in plasma levels, toxicity still occurs frequently after hematopoietic stem cell transplantation (HSCT). Toxicity (especially hepatotoxic effects) of intravenous (IV) Bu may be related to both Bu and/or N,N-dimethylacetamide (DMA), the solvent of Bu. In this study, we assessed the relation between the exposure of Bu and DMA with regards to the clinical outcome in children from two cohorts. In a two-centre study Bu and DMA AUC (area under the curve) were correlated in pediatric stem cell recipients to the risk of developing SOS and to the clinical outcome. In patients receiving Bu four times per day Bu levels >1,500 µmol/L minute correlate to an increased risk of developing a SOS. In the collective cohort, summarizing data of all 53 patients of this study, neither high area under the curve (AUC) of Bu nor high AUC of DMA appears to be an independent risk factor for the development of SOS in children. In this study neither Bu nor DMA was observed as an independent risk factor for the development of SOS. To identify subgroups (e.g., infants), in which Bu or DMA might be risk factors for the induction of SOS, larger cohorts have to be evaluated. © 2013 Wiley Periodicals, Inc.

Economic and clinical aspects of intravenous versus oral busulfan in adult patients for conditioning prior to HSCT.

PubMed

Berger, Karin; Schopohl, Dorothee; Rieger, Christina; Ostermann, Helmut

2015-12-01

Busulfan (BU) used as cytoreductive conditioning prior to hematopoietic stem cell transplantation (HSCT) is available as intravenous (IV) and oral (O) preparation. IV-BU has clinical advantages associated with relevant incremental costs. The aim was to determine the economic impact of IV-BU versus O-BU in adult HSCT recipients from a German health care providers' perspective. A budget-impact model (BIM) including costs and risks for oral mucositis (OM), infection with OM, and hepatic sinusoidal obstruction syndrome (SOS) was developed. Model inputs are literature data comparing clinical effects of IV-BU versus O-BU and German cost data (conditioning therapy, treatment of OM, infections, SOS without/with multiorgan failure) from literature and tariff lists. Base case calculations resulted the following: total costs of adverse events were €86,434 with O-BU and €44,376 with IV-BU for ten patients each. Considering costs of adverse events and drugs, about €5840 for ten patients receiving IV-BU are saved. Sensitivity analyses were conducted in several ways. Cost savings range between €4910 and €12,640 per ten patients for all adverse events and €2070 or €1140 per ten patients considering SOS only. Drug treatment of SOS and treatment of multiorgan failure during severe SOS are major cost drivers. Worst case scenario calculations (assuming -25% risk of all adverse events for O-BU and +25% for IV-BU) yield up to €27,570 per ten patients with IV-BU. Considering costs of adverse events and drugs, IV-BU is the dominant alternative from a German providers' perspective. For more comprehensive economic evaluations, additional epidemiological data, evidence on clinical outcomes, patient-reported outcomes, and treatment patterns are needed.

Comparison of pediatric allogeneic transplant outcomes using myeloablative busulfan with cyclophosphamide or fludarabine

PubMed Central

Artz, Andrew; Frangoul, Haydar; Loren, Alison; Mineishi, Shin

2018-01-01

Busulfan combined with cyclophosphamide (BuCy) has long been considered a standard myeloablative conditioning regimen for allogeneic hematopoietic cell transplantation (HCT), including both nonmalignant conditions and myeloid diseases. Substituting fludarabine for cyclophosphamide (BuFlu) to reduce toxicity without an increase in relapse has been increasingly performed in children, but without comparison with BuCy. We retrospectively analyzed 1781 children transplanted from 2008 to 2014 to compare the effectiveness of BuCy with BuFlu. Nonmalignant and malignant disease populations were analyzed separately. Overall mortality was comparable for children with nonmalignant conditions who received BuFlu or BuCy (relative risk [RR], 1.14, P = .52). Lower incidences of sinusoidal obstruction syndrome (P = .04), hemorrhagic cystitis (P = .04), and chronic graft-versus-host disease (P = .02) were observed after BuFlu, but the influence of the conditioning regimen could not be assessed by multivariate analysis because of the low frequency of these complications. Children transplanted for malignancies were more likely to receive BuFlu if they had higher hematopoietic cell transplantation-comorbidity index scores (P < .001) or their donor was unrelated and HLA-mismatched (P = .004). Nevertheless, there were no differences in transplant toxicities and comparable transplant-related mortality (RR, 1.2; P = .46), relapse (RR, 1.2; P = .15), and treatment failure (RR, 1.2; P = .12). BuFlu was associated with higher overall mortality (RR, 1.4; P = .008) related to inferior postrelapse survival (P = .001). Our findings demonstrated that outcomes after BuFlu are similar to those for BuCy for children, but for unclear reasons, those receiving BuFlu for malignancy may be at risk for shorter postrelapse survival. PMID:29844205

Conjugates of Superoxide Dismutase 1 with Amphiphilic Poly(2-oxazoline) Block Copolymers for Enhanced Brain Delivery: Synthesis, Characterization and Evaluation in vitro and in vivo

PubMed Central

Tong, Jing; Yi, Xiang; Luxenhofer, Robert; Banks, William A.; Jordan, Rainer; Zimmerman, Matthew C.; Kabanov, Alexander V.

2013-01-01

Superoxide dismutase 1 (SOD1) efficiently catalyzes dismutation of superoxide but its poor delivery to the target sites in the body, such as brain, hinders its use as a therapeutic agent for superoxide-associated disorders. Here to enhance the delivery of SOD1 across the blood brain barrier (BBB) and in neurons the enzyme was conjugated with poly(2-oxazoline) (POx) block copolymers, P(MeOx-b-BuOx) or P(EtOx-b-BuOx), comprised of 1) hydrophilic 2-methyl-2-oxazoline (MeOx) or 2-ethyl-2-oxazoline (EtOx) and 2) hydrophobic 2-butyl-2-oxazoline (BuOx) repeating units. The conjugates contained from 2 to 3 POx chains joining the protein amino groups via cleavable -(ss)- or non-cleavable –(cc)- linkers at the BuOx block terminus. They retained 30% to 50% of initial SOD1 activity, were conformationally and thermally stable and assembled in 8 or 20 nm aggregates in aqueous solution. They had little if any toxicity to CATH.a neurons and displayed enhanced uptake in these neurons as compared to native or PEGylated SOD1. Of the two conjugates, SOD1-(cc)-P(MeOx-b-BuOx) and SOD1-(cc)-P(EtOx-b-BuOx) compared, the latter was entering cells 4 to 7 times faster and at 6 h colocalized predominantly with endoplasmic reticulum (41 ± 3%) and mitochondria (21 ± 2%). Colocalization with endocytosis markers and pathway inhibition assays suggested that it was internalized through lipid raft/caveolae, also employed by the P(EtOx-b-BuOx) copolymer. The SOD activity in cell lysates and ability to attenuate angiotensin II (Ang II)-induced superoxide in live cells were increased for this conjugate compared to SOD1 and PEG-SOD1. Studies in mice showed that SOD1-POx had ca. 1.75 times longer half-life in blood than native SOD1 (28.4 vs 15.9 min) and after i.v. administration penetrated the BBB significantly faster than albumin to accumulate in brain parenchyma. The conjugate maintained high stability both in serum and in brain (77% vs. 84% at 1 h post injection). Its amount taken up by the brain reached a maximum value of 0.08%ID/g (percent of the injected dose taken up per gram of brain) 4 h post injection. The entry of SOD1-(cc)-P(EtOx-b-BuOx) to the brain was mediated by a non-saturable mechanism. Altogether, SOD1-POx conjugates are promising candidates as macromolecular antioxidant therapies for superoxide-associated diseases such as Ang II induced neuro-cardiovascular diseases. PMID:23163230

Synthesis and X-ray structures of dilithium complexes of the phosphonate anions [PhP(E)(N(t)Bu)(2)](2-) (E = O, S, Se, Te) and dimethylaluminum derivatives of [PhP(E)(N(t)Bu)(NH(t)Bu)](-) (E = S, Se).

PubMed

Briand, Glen G; Chivers, Tristram; Krahn, Mark; Parvez, Masood

2002-12-16

The dilithium salts of the phosphonate dianions [PhP(E)(N(t)Bu)(2)](2-) (E = O, S, Se) are generated by the lithiation of [PhP(E)(NH(t)Bu)(2)] with n-butyllithium. The formation of the corresponding telluride (E = Te) is achieved by oxidation of [Li(2)[PhP(N(t)Bu)(2)

Bu-2470, a new peptide antibiotic complex. II. Structure determination of Bu-2470 A, B1, B2a and B2b.

PubMed

Sugawara, K; Yonemoto, T; Konishi, M; Matsumoto, K; Miyaki, T; Kawaguchi, H

1983-06-01

The structures of Bu-2470 A, B1, B2a, and B2b have been determined. Bu-2470 A is a simple octapeptide having no fatty acid moiety, while Bu-2470 B1, B2a and B2b are octapeptides that have been acylated with a beta-hydroxy C11 or C10 fatty acid. The octapeptide structure of Bu-2470 components was found identical with that of octapeptin C1, hence generic names of octapeptin C0, C2, C3 and C4 are proposed for Bu-2470 A, B1, B2a and B2b, respectively.

cyclo-P4 Building Blocks: Achieving Non-Classical Fullerene Topology and Beyond.

PubMed

Dielmann, Fabian; Peresypkina, Eugenia V; Krämer, Barbara; Hastreiter, Florian; Johnson, Brian P; Zabel, Manfred; Heindl, Claudia; Scheer, Manfred

2016-11-14

The cyclo-P 4 complexes [Cp R Ta(CO) 2 (η 4 -P 4 )] (Cp R : Cp''=1,3-C 5 H 3 tBu 2 , Cp'''=1,2,4-C 5 H 2 tBu 3 ) turned out to be predestined for the formation of hollow spherical supramolecules with non-classical fullerene-like topology. The resulting assemblies constructed with CuX (X=Cl, Br) showed a highly symmetric 32-vertex core of solely four- and six-membered rings. In some supramolecules, the inner cavity was occupied by an additional CuX unit. On the other hand, using CuI, two different supramolecules with either peanut- or pear-like shapes and outer diameters in the range of 2-2.5 nm were isolated. Furthermore, the spherical supramolecules containing Cp''' ligands at tantalum are soluble in CH 2 Cl 2 . NMR spectroscopic investigations in solution revealed the formation of isomeric supramolecules owing to the steric hindrance caused by the third tBu group on the Cp''' ligand. In addition, a 2D coordination polymer was obtained and structurally characterized. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

cyclo‐P4 Building Blocks: Achieving Non‐Classical Fullerene Topology and Beyond

PubMed Central

Dielmann, Fabian; Peresypkina, Eugenia V.; Krämer, Barbara; Hastreiter, Florian; Johnson, Brian P.; Zabel, Manfred; Heindl, Claudia

2016-01-01

Abstract The cyclo‐P4 complexes [CpRTa(CO)2(η4‐P4)] (CpR: Cp′′=1,3‐C5H3tBu2, Cp′′′=1,2,4‐C5H2tBu3) turned out to be predestined for the formation of hollow spherical supramolecules with non‐classical fullerene‐like topology. The resulting assemblies constructed with CuX (X=Cl, Br) showed a highly symmetric 32‐vertex core of solely four‐ and six‐membered rings. In some supramolecules, the inner cavity was occupied by an additional CuX unit. On the other hand, using CuI, two different supramolecules with either peanut‐ or pear‐like shapes and outer diameters in the range of 2–2.5 nm were isolated. Furthermore, the spherical supramolecules containing Cp′′′ ligands at tantalum are soluble in CH2Cl2. NMR spectroscopic investigations in solution revealed the formation of isomeric supramolecules owing to the steric hindrance caused by the third tBu group on the Cp′′′ ligand. In addition, a 2D coordination polymer was obtained and structurally characterized. PMID:27781348

Antifungal activity of rimocidin and a new rimocidin derivative BU16 produced by Streptomyces mauvecolor BU16 and their effects on pepper anthracnose.

PubMed

Jeon, B J; Kim, J D; Han, J W; Kim, B S

2016-05-01

The objective of this study was to explore antifungal metabolites targeting fungal cell envelope and to evaluate the control efficacy against anthracnose development in pepper plants. A natural product library comprising 3000 microbial culture extracts was screened via an adenylate kinase (AK)-based cell lysis assay to detect antifungal metabolites targeting the cell envelope of plant-pathogenic fungi. The culture extract of Streptomyces mauvecolor strain BU16 displayed potent AK-releasing activity. Rimocidin and a new rimocidin derivative, BU16, were identified from the extract as active constituents. BU16 is a tetraene macrolide containing a six-membered hemiketal ring with an ethyl group side chain instead of the propyl group in rimocidin. Rimocidin and BU16 showed broad-spectrum antifungal activity against various plant-pathogenic fungi and demonstrated potent control efficacy against anthracnose development in pepper plants. Antifungal metabolites produced by S. mauvecolor strain BU16 were identified to be rimocidin and BU16. The compounds displayed potent control efficacy against pepper anthracnose. Rimocidin and BU16 would be active ingredients of disease control agents disrupting cell envelope of plant-pathogenic fungi. The structure and antifungal activity of rimocidin derivative BU16 is first described in this study. © 2016 The Society for Applied Microbiology.

A model for the CO-inhibited form of [NiFe] hydrogenase: synthesis of (CO)3Fe(μ-StBu)3Ni{SC6H3-2,6-(mesityl)2} and reversible CO addition at the Ni site

PubMed Central

Ohki, Yasuhiro; Yasumura, Kazunari; Ando, Masaru; Shimokata, Satoko; Tatsumi, Kazuyuki

2010-01-01

A [NiFe] hydrogenase model compound having a distorted trigonal-pyramidal nickel center, (CO)3Fe(μ-StBu)3Ni(SDmp), 1 (Dmp = C6H3-2,6-(mesityl)2), was synthesized from the reaction of the tetranuclear Fe-Ni-Ni-Fe complex [(CO)3Fe(μ-StBu)3Ni]2(μ-Br)2, 2 with NaSDmp at -40 °C. The nickel site of complex 1 was found to add CO or CNtBu at -40 °C to give (CO)3Fe(StBu)(μ-StBu)2Ni(CO)(SDmp), 3, or (CO)3Fe(StBu)(μ-StBu)2Ni(CNtBu)(SDmp), 4, respectively. One of the CO bands of 3, appearing at 2055 cm-1 in the infrared spectrum, was assigned as the Ni-CO band, and this frequency is comparable to those observed for the CO-inhibited forms of [NiFe] hydrogenase. Like the CO-inhibited forms of [NiFe] hydrogenase, the coordination of CO at the nickel site of 1 is reversible, while the CNtBu adduct 4 is more robust. PMID:20147622

Friend or Ally? A Question for New Zealand

DTIC Science & Technology

1991-05-01

Many close observers of the manoeuvring which went on from the time the Lange government took power in July 1984 until George Shultz declared a...d s - - bu t we par t . George P. Shultz Manila, July 1986 ~ ITH THE WORDS, "we part," the Secretary of State for the United States of...the Western alliance. George Shultz’ simple words marked an historic turn- ing point in United States/New Zealand relations and, perhaps even more

Single-unit umbilical cord blood transplantation from unrelated donors in patients with hematological malignancy using busulfan, thiotepa, fludarabine and ATG as myeloablative conditioning regimen.

PubMed

Sanz, J; Boluda, J C H; Martín, C; González, M; Ferrá, C; Serrano, D; de Heredia, C D; Barrenetxea, C; Martinez, A M; Solano, C; Sanz, M A; Sanz, G F

2012-10-01

Attempts to optimize outcomes in cord blood transplantation (CBT) by using new conditioning regimens and standardization of cord blood unit selection are warranted. In all, 88 patients (18 children and 70 adults) with hematological malignancy from nine Spanish institutions underwent a single-unit CBT after an i.v. BU-based myeloablative conditioning regimen. All evaluable patients except one engrafted. The overall cumulative incidence (CI) of myeloid engraftment was 94% at a median time of 19 days. In multivariate analysis, nonadvanced disease stage was the only factor with a favorable impact on myeloid engraftment. The CI of acute GVHD grades II-IV and chronic extensive GVHD were 24% each. The CI of nonrelapse mortality at 100 days, 180 days and 5 years was 14, 23 and 44%, respectively. The 5-year CI of relapse was 18%, whereas disease-free survival (DFS) was 46%, 39% and 11% for patients transplanted in early, intermediate and advanced stages of the disease, respectively. Our study shows high rates of engraftment with fast neutrophil recovery in patients undergoing single-unit CBT using a BU-based conditioning regimen. Long-term DFS can be achieved in a substantial number of patients with high-risk hematological malignancies, particularly when transplanted in an early stage of the disease.

Widespread Refreezing of Both Surface and Basal Melt Water Beneath the Greenland Ice Sheet

NASA Astrophysics Data System (ADS)

Bell, R. E.; Tinto, K. J.; Das, I.; Wolovick, M.; Chu, W.; Creyts, T. T.; Frearson, N.

2013-12-01

The isotopically and chemically distinct, bubble-free ice observed along the Greenland Ice Sheet margin both in the Russell Glacier and north of Jacobshavn must have formed when water froze from subglacial networks. Where this refreezing occurs and what impact it has on ice sheet processes remain unclear. We use airborne radar data to demonstrate that freeze-on to the ice sheet base and associated deformation produce large ice units up to 700 m thick throughout northern Greenland. Along the ice sheet margin, in the ablation zone, surface meltwater, delivered via moulins, refreezes to the ice sheet base over rugged topography. In the interior, water melted from the ice sheet base is refrozen and surrounded by folded ice. A significant fraction of the ice sheet is modified by basal freeze-on and associated deformation. For the Eqip and Petermann catchments, representing the ice sheet margin and interior respectively, extensive airborne radar datasets show that 10%-13% of the base of the ice sheet and up to a third of the catchment width is modified by basal freeze-on. The interior units develop over relatively subdued topography with modest water flux from basal melt where conductive cooling likely dominates. Steps in the bed topography associated with subglacial valley networks may foster glaciohydraulic supercooling. The ablation zone units develop where both surface melt and crevassing are widespread and large volumes of surface meltwater will reach the base of the ice sheet. The relatively steep topography at the upslope edge of the ablation zone units combined with the larger water flux suggests that supercooling plays a greater role in their formation. The ice qualities of the ablation zone units should reflect the relatively fresh surface melt whereas the chemistry of the interior units should reflect solute-rich basal melt. Changes in basal conditions such as the presence of till patches may contribute to the formation of the large basal units near the Northeast Ice Stream. The contrasting rheology of glacial and interglacial ice may also enhance the deformation associated with freeze-on beneath large ice sheets. The occurrence of basal units both in the ice sheet interior and in the thermally very different ablation zone indicates refreezing is widespread and can occur in many environments beneath an ice sheet. This process appears to influence the morphology and behavior of the ice sheet from top to bottom.

Effects of hypnotic bromovalerylurea on microglial BV2 cells.

PubMed

Kawasaki, Shun; Abe, Naoki; Ohtake, Fumito; Islam, Afsana; Choudhury, Mohammed Emamussalehin; Utsunomiya, Ryo; Kikuchi, Satoshi; Nishihara, Tasuku; Kuwabara, Jun; Yano, Hajime; Watanabe, Yuji; Aibiki, Mayuki; Yorozuya, Toshihiro; Tanaka, Junya

2017-06-01

An old sedative and hypnotic bromovalerylurea (BU) has anti-inflammatory effects. BU suppressed nitric oxide (NO) release and proinflammatory cytokine expression by lipopolysaccharide (LPS)-treated BV2 cells, a murine microglial cell line. However, BU did not inhibit LPS-induced nuclear translocation of nuclear factor-κB and subsequent transcription. BU suppressed LPS-induced phosphorylation of signal transducer and activator of transcription 1 (STAT1) and expression of interferon regulatory factor 1 (IRF1). The Janus kinase 1 (JAK1) inhibitor filgotinib suppressed the NO release much more weakly than that of BU, although filgotinib almost completely prevented LPS-induced STAT1 phosphorylation. Knockdown of JAK1, STAT1, or IRF1 did not affect the suppressive effects of BU on LPS-induced NO release by BV2 cells. A combination of BU and filgotinib synergistically suppressed the NO release. The mitochondrial complex I inhibitor rotenone, which did not prevent STAT1 phosphorylation or IRF1 expression, suppressed proinflammatory mediator expression less significantly than BU. BU and rotenone reduced intracellular ATP (iATP) levels to a similar extent. A combination of rotenone and filgotinib suppressed NO release by LPS-treated BV2 cells as strongly as BU. These results suggest that anti-inflammatory actions of BU may be attributable to the synergism of inhibition of JAK1/STAT1-dependent pathways and reduction in iATP level. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

Progression from Mild Cognitive Impairment to Alzheimer's disease: effects of gender, butyrylcholinesterase genotype and rivastigmine treatment

PubMed Central

Ferris, Steven; Nordberg, Agneta; Soininen, Hilkka; Darreh-Shori, Taher; Lane, Roger

2014-01-01

Objective Evaluate the influence of gender and butyrylcholinesterase (BuChE) genotype on incidence of progression to AD, rate of cognitive and functional decline, and response to rivastigmine treatment in mild cognitive impairment (MCI) subjects. Methods This retrospective exploratory analysis from a 3–4 year, randomized, placebo-controlled study of rivastigmine in MCI subjects included participants who consented to pharmacogenetic testing. Results Of 1018 total patients, 490 (253 [52%] female) were successfully genotyped for BuChE. In subjects receiving placebo, the BuChE wt/wt genotype was associated with a statistically significantly higher rate of progression to AD and functional decline in women, compared with men with the BuChE wt/wt genotype. In subjects with a BuChE-K allele receiving placebo, incidence of progression to AD and rate of functional decline were not significantly different by gender, however cognitive decline was significantly faster in men. Statistically significant benefits of rivastigmine treatment on progression to AD, functional decline, ventricular volume expansion, whole brain atrophy and white matter loss were evident in female BuChE wt/wt. Conclusion Gender appears to differentially influence the type of decline in MCI subjects according to BuChE genotype, with more rapid progression of cognitive decline in male BuChE-K, and more rapid progression to AD and functional decline in female BuChE wt/wt. Cognitive decline in male BuChE-K and functional decline and progression to AD in female BuChE wt/wt were significantly attenuated by rivastigmine. Rivastigmine treatment also significantly reduced ventricular expansion, whole brain atrophy rate and white matter loss in female BuChE wt/wt, suggesting a possible disease-modifying effect. PMID:19617863

Intravenous Busulfan Compared with Total Body Irradiation Pretransplant Conditioning for Adults with Acute Lymphoblastic Leukemia.

PubMed

Kebriaei, Partow; Anasetti, Claudio; Zhang, Mei-Jie; Wang, Hai-Lin; Aldoss, Ibrahim; de Lima, Marcos; Khoury, H Jean; Sandmaier, Brenda M; Horowitz, Mary M; Artz, Andrew; Bejanyan, Nelli; Ciurea, Stefan; Lazarus, Hillard M; Gale, Robert Peter; Litzow, Mark; Bredeson, Christopher; Seftel, Matthew D; Pulsipher, Michael A; Boelens, Jaap-Jan; Alvarnas, Joseph; Champlin, Richard; Forman, Stephen; Pullarkat, Vinod; Weisdorf, Daniel; Marks, David I

2018-04-01

Total body irradiation (TBI) has been included in standard conditioning for acute lymphoblastic leukemia (ALL) before hematopoietic cell transplantation (HCT). Non-TBI regimens have incorporated busulfan (Bu) to decrease toxicity. This retrospective study analyzed TBI and Bu on outcomes of ALL patients 18-60 years old, in first or second complete remission (CR), undergoing HLA-compatible sibling, related, or unrelated donor HCT, who reported to the Center for International Blood and Marrow Transplant Research from 2005 to 2014. TBI plus etoposide (25%) or cyclophosphamide (75%) was used in 819 patients, and intravenous Bu plus fludarabine (41%), clofarabine (30%), cyclophosphamide (15%), or melphalan (13%) was used in 299 patients. Bu-containing regimens were analyzed together, since no significant differences for patient outcomes were noted between them. Bu patients were older, with better performance status; took longer to achieve first CR and receive HCT; were treated more recently; and were more likely to receive peripheral blood grafts, antithymocyte globulin, or tyrosine kinase inhibitors. With median follow-up of 3.6 years for Bu and 5.3 years for TBI, adjusted 3-year outcomes showed treatment-related mortality Bu 19% versus TBI 25% (P = .04); relapse Bu 37% versus TBI 28% (P = .007); disease-free survival (DFS) Bu 45% versus TBI 48% (P = .35); and overall survival (OS) Bu 57% versus TBI 53% (P = .35). In multivariate analysis, Bu patients had higher risk of relapse (relative risk, 1.46; 95% confidence interval, 1.15 to 1.85; P = .002) compared with TBI patients. Despite the higher relapse, Bu-containing conditioning led to similar OS and DFS following HCT for ALL. Copyright © 2018. Published by Elsevier Inc.

An efficient, maintenance free and approved method for spectroscopic control and monitoring of blend uniformity: The moving F-test.

PubMed

Besseling, Rut; Damen, Michiel; Tran, Thanh; Nguyen, Thanh; van den Dries, Kaspar; Oostra, Wim; Gerich, Ad

2015-10-10

Dry powder mixing is a wide spread Unit Operation in the Pharmaceutical industry. With the advent of in-line Near Infrared (NIR) Spectroscopy and Quality by Design principles, application of Process Analytical Technology to monitor Blend Uniformity (BU) is taking a more prominent role. Yet routine use of NIR for monitoring, let alone control of blending processes is not common in the industry, despite the improved process understanding and (cost) efficiency that it may offer. Method maintenance, robustness and translation to regulatory requirements have been important barriers to implement the method. This paper presents a qualitative NIR-BU method offering a convenient and compliant approach to apply BU control for routine operation and process understanding, without extensive calibration and method maintenance requirements. The method employs a moving F-test to detect the steady state of measured spectral variances and the endpoint of mixing. The fundamentals and performance characteristics of the method are first presented, followed by a description of the link to regulatory BU criteria, the method sensitivity and practical considerations. Applications in upscaling, tech transfer and commercial production are described, along with evaluation of the method performance by comparison with results from quantitative calibration models. A full application, in which end-point detection via the F-test controls the blending process of a low dose product, was successfully filed in Europe and Australia, implemented in commercial production and routinely used for about five years and more than 100 batches. Copyright © 2015 Elsevier B.V. All rights reserved.

Safety and Efficacy of Once-Daily Intravenous Busulfan in Allogeneic Transplantation: A Matched-Pair Analysis.

PubMed

Kako, Shinichi; Fujiwara, Shinichiro; Sato, Miki; Kimura, Shun-Ichi; Nakasone, Hideki; Ohashi, Kazuteru; Kawakita, Toshiro; Maeda, Tetsuo; Morishita, Takanobu; Suzuki, Ritsuro; Fukuda, Takahiro; Ichinohe, Tatsuo; Kurata, Mio; Atsuta, Yoshiko; Kanda, Yoshinobu

2018-04-19

Compared with 4-times-daily infusion of intravenous busulfan (ivBU4), the safety and efficacy of once-daily infusion of ivBU (ivBU1) has not been fully clarified. We have been routinely using ivBU1 in a conditioning regimen in adult patients with myeloid malignancy who undergo allogeneic hematopoietic stem cell transplantation. In this study, a total of 91 patients who received ivBU1 for 2 days (n = 18) or 4 days (n = 73) in our institutions were compared with 273 control patients who received ivBU4, who were matched for age, sex, performance status, disease risk, conditioning regimen, and donor type, selected from the database of the Japanese Society for Hematopoietic Cell Transplantation using optimal matching algorithms. One-year overall survival (56.8% versus 57.1%, P = .94), disease-free survival (51.6% versus 50.8%, P = .73), relapse rate (28.5% versus 26.2%, P = .94), nonrelapse mortality (19.9% versus 23.0%, P = .71), and the incidence of graft-versus-host disease were not significantly different between the ivBU1 and ivBU4 groups. In patients who received ivBU1, neutrophil recovery was slower (median days: 22 versus 17, P = .001), and the incidence of veno-occlusive disease was lower (2.6% versus 17.4%, P = .04). In conclusion, ivBU1 can be safely administered with clinical outcomes similar to those with ivBU4. Copyright © 2018 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Design and synthesis of single-source molecular precursors to homogeneous multi-component oxide materials

NASA Astrophysics Data System (ADS)

Fujdala, Kyle Lee

This dissertation describes the syntheses of single-source molecular precursors to multi-component oxide materials. These molecules possess a core metal or element with various combinations of -OSi(O tBu)3, -O2P(OtBu) 2, and -OB[OSi(OtBu)3] 2 ligands. Such molecules decompose under mild thermolytic conditions (<200°C) to provide homogeneous carbon-free materials via the elimination of isobutylene and water. A gel is formed when thermolyses are performed in non-polar solvents, and subsequent drying of the gel in a conventional manner yields high surface area xerogels. This thermolytic molecular precursor (TMP) approach has been utilized to provide a variety of oxide materials with tailored properties. In addition, the oxygen rich environment of the molecular precursors coupled with the presence of M-O-E heterolinkages permits use of them as models for oxide-supported metal species and multi-component oxides. Significantly, the first complexes to contain three or more heteroelements suitable for use in the TMP method have been synthesized. Compounds for use as single-source molecular precursors have been synthesized containing Al, B, Cr, Hf, Mo, V, W, and Zr, and their thermal transformations have been examined. Heterogeneous catalytic reactions have been examined for selected materials. Also, cothermolyses of molecular precursors and additional molecules (i.e., metal alkoxides) have been utilized to provide materials with several components for potential use as catalysts or catalyst supports. Reactions of one and two equivs of HOSi(OtBu) 3 with Cr(OtBu)4 afforded the first Cr(IV) alkoxysiloxy complexes (tBuO) 3CrOSi(OtBu)3 and ( tBuO)2Cr[OSi(OtBu) 3]2, respectively. The high-yielding, convenient synthesis of (tBuO)3CrOSi(O tBu)3 make this complex a useful single-source molecular precursor, via the TMP method, to Cr/Si/O materials. The thermal transformations of (tBuO)3CrOSi(O tBu)3 and (tBuO) 2Cr[OSi(OtBu)3]2 to chromia-silica materials occurr at low temperatures (≤180°C), to give isobutene as the major carbon-containing product. The material generated from the solid-state conversion of (tBuO) 3CrOSi(OtBu)3 (CrOS ss) has an unexpectedly high surface area of 315 m2 g-1 that is slightly reduced to 275 m2 g-1 after calcination at 500°C in O2. The xerogel obtained by the thermolysis of an n-octane solution of (tBuO)3CrOSi(O tBu)3 (CrOSixg) has a surface area of 315 m2 g-1 that is reduced to 205 m2 g-1 upon calcination at 500°C. Powder X-ray diffraction (PXRD) analysis revealed that Cr2O 3 is the only crystalline species present in CrOSiss and CrOSixg after calcination at temperatures up to 1200°C in O2. (Abstract shortened by UMI.)

Controlled Pd(0)/t Bu3P Catalyzed Suzuki Cross-Coupling Polymerization of AB-Type Monomers with ArPd(t Bu3P)X or Pd2(dba)3/t Bu3P/ArX as the Initiator

DOE PAGES

Zhang, Honghai; Xing, Chun-Hui; Hu, Qiao-Sheng; ...

2015-02-05

The synthesis of well-defined and functionalized conjugated polymers, which are essential in the development of efficient organic electronics, through Suzuki cross-coupling polymerizations has been a challenging task. We developed controlled Pd(0)/t-Bu3P-catalyzed Suzuki cross-coupling polymerizations of AB-type monomers via the chain-growth mechanism with a series of in situ generated ArPd(t-Bu3P)X (X = I, Br, Cl) complexes as initiators. Among them, the combinations of Pd2(dba)3/t-Bu3P/p-BrC6H4I, Pd2(dba)3/t-Bu3P/p-BrC6H4CH2OH and Pd2(dba)3/t-Bu3P/p-PhCOC6H4Br were identified as highly robust initiator systems, resulting in polymers with predictable molecular weight and narrow polydispersity (PDI~1.13-1.20). In addition, Pd2(dba)3/t-Bu3P/p-BrC6H4CH2OH and Pd2(dba)3/t-Bu3P/p-PhCOC6H4Br initiator systems afforded functional polymers with >95% fidelity. Our results pavedmore » the road to access well-defined conjugated polymers, including conjugated polymers with complex polymer architectures such as block copolymers and branch copolymers.« less

Bacterial diversity in Buruli ulcer skin lesions: Challenges in the clinical microbiome analysis of a skin disease.

PubMed

Van Leuvenhaege, Chloé; Vandelannoote, Koen; Affolabi, Dissou; Portaels, Françoise; Sopoh, Ghislain; de Jong, Bouke C; Eddyani, Miriam; Meehan, Conor J

2017-01-01

Buruli ulcer (BU) is an infectious disease caused by Mycobacterium ulcerans and considered the third most prevalent mycobacterial disease in humans. Secondary bacterial infections in open BU lesions are the main cause of pain, delayed healing and systemic illness, resulting in prolonged hospital stay. Thus, understanding the diversity of bacteria, termed the microbiome, in these open lesions is important for proper treatment. However, adequately studying the human microbiome in a clinical setting can prove difficult when investigating a neglected tropical skin disease due to its rarity and the setting. Using 16S rRNA sequencing, we determined the microbial composition of 5 BU lesions, 3 non-BU lesions and 3 healthy skin samples. Although no significant differences in diversity were found between BU and non-BU lesions, the former were characterized by an increase of Bacteroidetes compared to the non-BU wounds and the BU lesions also contained significantly more obligate anaerobes. With this molecular-based study, we were also able to detect bacteria that were missed by culture-based methods in previous BU studies. Our study suggests that BU may lead to changes in the skin bacterial community within the lesions. However, in order to determine if such changes hold true across all BU cases and are either a cause or consequence of a specific wound environment, further microbiome studies are necessary. Such skin microbiome analysis requires large sample sizes and lesions from the same body site in many patients, both of which can be difficult for a rare disease. Our study proposes a pipeline for such studies and highlights several drawbacks that must be considered if microbiome analysis is to be utilized for neglected tropical diseases.

Unprecedented linking of two polyoxometalate units with a metal-metal multiple bond.

PubMed

Sokolov, Maxim N; Korenev, Vladimir S; Izarova, Natalya V; Peresypkina, Eugenia V; Vicent, Cristian; Fedin, Vladimir P

2009-03-02

The reaction of (Bu(4)N)(2)[Re(2)Cl(8)] with lacunary Keggin polyoxometalate K(7)[PW(11)O(39)] in water produces a new dumbbell-shaped heteropolyoxometalate anion, [Re(2)(PW(11)O(39))(2)](8-), whose structure contains a central Re(2) core with a quadruple bond between Re atoms (Re-Re 2.25 A), coordinated to two polyoxometalate units. This complex represents the first example of the direct linking of two polyoxometalate units via a metal-metal multiple bond. The compounds were characterized by X-ray analysis, IR, and electrospray ionization mass spectrometry.

Weighting of NMME temperature and precipitation forecasts across Europe

NASA Astrophysics Data System (ADS)

Slater, Louise J.; Villarini, Gabriele; Bradley, A. Allen

2017-09-01

Multi-model ensemble forecasts are obtained by weighting multiple General Circulation Model (GCM) outputs to heighten forecast skill and reduce uncertainties. The North American Multi-Model Ensemble (NMME) project facilitates the development of such multi-model forecasting schemes by providing publicly-available hindcasts and forecasts online. Here, temperature and precipitation forecasts are enhanced by leveraging the strengths of eight NMME GCMs (CCSM3, CCSM4, CanCM3, CanCM4, CFSv2, GEOS5, GFDL2.1, and FLORb01) across all forecast months and lead times, for four broad climatic European regions: Temperate, Mediterranean, Humid-Continental and Subarctic-Polar. We compare five different approaches to multi-model weighting based on the equally weighted eight single-model ensembles (EW-8), Bayesian updating (BU) of the eight single-model ensembles (BU-8), BU of the 94 model members (BU-94), BU of the principal components of the eight single-model ensembles (BU-PCA-8) and BU of the principal components of the 94 model members (BU-PCA-94). We assess the forecasting skill of these five multi-models and evaluate their ability to predict some of the costliest historical droughts and floods in recent decades. Results indicate that the simplest approach based on EW-8 preserves model skill, but has considerable biases. The BU and BU-PCA approaches reduce the unconditional biases and negative skill in the forecasts considerably, but they can also sometimes diminish the positive skill in the original forecasts. The BU-PCA models tend to produce lower conditional biases than the BU models and have more homogeneous skill than the other multi-models, but with some loss of skill. The use of 94 NMME model members does not present significant benefits over the use of the 8 single model ensembles. These findings may provide valuable insights for the development of skillful, operational multi-model forecasting systems.

The role of basal insulin and GLP-1 receptor agonist combination products in the management of type 2 diabetes

PubMed Central

Inman, Taylor R.; Plyushko, Erika; Austin, Nicholas P.; Johnson, Jeremy L.

2018-01-01

The prevalence of type 2 diabetes necessitates the development of new treatment options to individualize therapy. Basal insulin has been a standard treatment option for years, while glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have grown in use over the past decade due to glucose-lowering efficacy and weight loss potential. There are two new combination injectable products that have recently been approved combining basal insulins with GLP-1 RAs in single pen-injector devices. United States guidelines recently emphasize the option to use combination injectable therapy with GLP-1 RAs and basal insulin once the basal insulin has been optimally titrated as a second- or third-line agent in addition to metformin without reaching the goal A1c. Insulin glargine/lixisenatide 100/33 (IGlarLixi) can be dosed between 15 and 60 units once daily from a single pen-injector device. Insulin degludec/liraglutide 100/3.6 (IDegLira) can be dosed between 10 and 50 units once daily, also from a single pen-injector device. Maximum doses, while measured in units, correspond to limits defined by each individual GLP-1 RA. The dual use of basal insulin plus GLP-1 RA is non-inferior compared with basal insulin plus a single injection of prandial insulin at the largest meal and compared with twice daily-dosed premixed insulins; and this combination is associated with weight loss and less hypoglycemia. These new combination products could help providers effectively and efficiently follow clinical practice guidelines while enhancing patient adherence with injectable medications. PMID:29796245

The role of basal insulin and GLP-1 receptor agonist combination products in the management of type 2 diabetes.

PubMed

Inman, Taylor R; Plyushko, Erika; Austin, Nicholas P; Johnson, Jeremy L

2018-05-01

The prevalence of type 2 diabetes necessitates the development of new treatment options to individualize therapy. Basal insulin has been a standard treatment option for years, while glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have grown in use over the past decade due to glucose-lowering efficacy and weight loss potential. There are two new combination injectable products that have recently been approved combining basal insulins with GLP-1 RAs in single pen-injector devices. United States guidelines recently emphasize the option to use combination injectable therapy with GLP-1 RAs and basal insulin once the basal insulin has been optimally titrated as a second- or third-line agent in addition to metformin without reaching the goal A1c. Insulin glargine/lixisenatide 100/33 (IGlarLixi) can be dosed between 15 and 60 units once daily from a single pen-injector device. Insulin degludec/liraglutide 100/3.6 (IDegLira) can be dosed between 10 and 50 units once daily, also from a single pen-injector device. Maximum doses, while measured in units, correspond to limits defined by each individual GLP-1 RA. The dual use of basal insulin plus GLP-1 RA is non-inferior compared with basal insulin plus a single injection of prandial insulin at the largest meal and compared with twice daily-dosed premixed insulins; and this combination is associated with weight loss and less hypoglycemia. These new combination products could help providers effectively and efficiently follow clinical practice guidelines while enhancing patient adherence with injectable medications.

A climatology of fine absorbing biomass burning, urban and industrial aerosols detected from satellites

NASA Astrophysics Data System (ADS)

Kalaitzi, Nikoleta; Hatzianastassiou, Nikos; Gkikas, Antonis; Papadimas, Christos D.; Torres, Omar; Mihalopoulos, Nikos

2017-04-01

Natural biomass burning (BB) along with anthropogenic urban and industrial aerosol particles, altogether labeled here as BU aerosols, contain black and brown carbon which both absorb strongly the solar radiation. Thus, BU aerosols warm significantly the atmosphere also causing adjustments to cloud properties, which traditionally are known as cloud indirect and semi-direct effects. Given the role of the effects of BU aerosols for contemporary and future climate change, and the uncertainty associated with BU, both ascertained by the latest IPCC reports, there is an urgent need for improving our knowledge on the spatial and temporal variability of BU aerosols all over the globe. Over the last few decades, thanks to the rapid development of satellite observational techniques and retrieval algorithms it is now possible to detect BU aerosols based on satellite measurements. However, care must be taken in order to ensure the ability to distinguish BU from other aerosol types usually co-existing in the Earth's atmosphere. In the present study, an algorithm is presented, based on a synergy of different satellite measurements, aiming to identify and quantify BU aerosols over the entire globe and during multiple years. The objective is to build a satellite-based climatology of BU aerosols intended for use for various purposes. The produced regime, namely the spatial and temporal variability of BU aerosols, emphasizes the BU frequency of occurrence and their intensity, in terms of aerosol optical depth (AOD). The algorithm is using the following aerosol optical properties describing the size and atmospheric loading of BU aerosols: (i) spectral AOD, (ii) Ångström Exponent (AE), (iii) Fine Fraction (FF) and (iv) Aerosol Index (AI). The relevant data are taken from Collection 006 MODIS-Aqua, except for AI which is taken from OMI-Aura. The identification of BU aerosols by the algorithm is based on a specific thresholding technique, with AI≥1.5, AE≥1.2 and FF≥0.6 threshold values. The study spans the 11-year period 2005-2015, which enables to examine the inter-annual variability and possible changes of BU aerosols. Emphasis is given on specific world areas known to be sources of BU emissions. An effort is also made to separate with the algorithm the BB from BU aerosols, aiming to create a satellite database of biomass burning aerosols. The results of the algorithm, as to BB aerosols and the ability to separate them, are evaluated through comparisons against the global satellite databases of MODIS active fire counts as well as AIRS carbon monoxide (CO), which is a key indicator of presence of biomass burning activities. The algorithm estimates frequencies of occurrence of BU aerosols reaching up to 10 days/year and AOD values up to 1.5 or even larger. The results indicate the existence of seasonal cycles of biomass burning in south and central Africa as well as in South America (Amazonia), with highest BU frequencies during June-September, December-February and August-October, respectively, whereas they successfully reproduce features like the export of African BB aerosols into the Atlantic Ocean.

Bu-2470, a new peptide antibiotic complex. I. Production, isolation and properties of Bu-2470 A, B1 and B2.

PubMed

Konishi, M; Sugawara, K; Tomita, K; Matsumoto, K; Miyaki, T; Fujisawa, K; Tsukiura, H; Kawaguchi, H

1983-06-01

A strain of Bacillus circulans produced a complex of basic peptide antibiotics designated Bu-2470, which was found to contain four active components, A, B1, B2a and B2b. Bu-2470 A specifically inhibited various Pseudomonas species including P. aeruginosa, P. maltophilia and P. putida, but otherwise its antibacterial spectrum was limited to certain Gram-negative organisms. Bu-2470 B1 and B2 (B2a + B2b) showed broad antibiotic activity against Gram-positive and Gram-negative bacteria including Pseudomonas species. The physicochemical and biological properties of Bu-2470 B1 and B2 are very similar to those of the octapeptin group of antibiotics.

The efficacy and safety of bufadienolides-loaded nanostructured lipid carriers.

PubMed

Li, Fang; Weng, Yan; Wang, Lihui; He, Haibing; Yang, Jingyu; Tang, Xing

2010-06-30

Bufadienolides-loaded nanostructured lipid carriers (BU-NLC) were prepared for parenteral application using glyceryl monostearate as solid core, medium-chain triglyceride and oleic acid as liquid lipid material, and Lipoid E-80, sodium deoxycholate and pluronic F68 as stabilizers. In this study, the in vitro cytotoxicity, pharmacokinetics, biodistribution, antitumor efficacy and safety of BU-NLC were evaluated. Against human astrocytoma cell line (U87-MG) and human gastric carcinoma cell line (HGC-27) BU-NLC exhibited cytotoxicity that was similar to that of the free drug, and superior to that of the commercially available fluorouracil injection. BU-NLC exhibited a linear pharmacokinetic behavior at doses ranging from 0.25 to 1.0 mg/kg. The improved pharmacokinetic profile of bufadienolides when formulated in BU-NLC resulted in a higher plasma concentration and lower clearance after intravenous administration compared with bufadienolides solution (BU-S). A biodistribution study indicated that bufadienolides were mainly distributed in the lung, spleen, brain and kidney, and the longest retention was observed in the brain. A sarcoma-180 tumor model further confirmed the advantages of BU-NLC versus BU-S. Hemolysis and acute toxicity investigations showed that BU-NLC was safe when given by intravenous injection with reduced toxicity. In conclusion, the NLC system is a promising approach for the intravenous delivery of bufadienolides. 2010 Elsevier B.V. All rights reserved.

High-Tg Polynorbornene-Based Block and Random Copolymers for Butanol Pervaporation Membranes

NASA Astrophysics Data System (ADS)

Register, Richard A.; Kim, Dong-Gyun; Takigawa, Tamami; Kashino, Tomomasa; Burtovyy, Oleksandr; Bell, Andrew

Vinyl addition polymers of substituted norbornene (NB) monomers possess desirably high glass transition temperatures (Tg); however, until very recently, the lack of an applicable living polymerization chemistry has precluded the synthesis of such polymers with controlled architecture, or copolymers with controlled sequence distribution. We have recently synthesized block and random copolymers of NB monomers bearing hydroxyhexafluoroisopropyl and n-butyl substituents (HFANB and BuNB) via living vinyl addition polymerization with Pd-based catalysts. Both series of polymers were cast into the selective skin layers of thin film composite (TFC) membranes, and these organophilic membranes investigated for the isolation of n-butanol from dilute aqueous solution (model fermentation broth) via pervaporation. The block copolymers show well-defined microphase-separated morphologies, both in bulk and as the selective skin layers on TFC membranes, while the random copolymers are homogeneous. Both block and random vinyl addition copolymers are effective as n-butanol pervaporation membranes, with the block copolymers showing a better flux-selectivity balance. While polyHFANB has much higher permeability and n-butanol selectivity than polyBuNB, incorporating BuNB units into the polymer (in either a block or random sequence) limits the swelling of the polyHFANB and thereby improves the n-butanol pervaporation selectivity.

Functionalization of Bambusurils by thiol-ene click reaction and new, facile method for the preparation of anion-free Bambus[6]urils.

PubMed

Heck, Marie-Pierre; Azazna, Djamille; Lafosse, Marine; Wang, Jialan; Rivollier, Julie; Ben Cheikh, Imen; Meyer, Michel; Thuéry, Pierre; Dognon, Jean-Pierre; Huber, Gaspard

2018-05-03

New sulfide-functionalized bambus[4]urils ((RS)8BU[4]) and bambus[6]urils ((RS)12BU[6]) have been synthesized through thiol-ene click coupling reactions (TEC) of allylbambus[n]urils. Synthesis of BU[6] derivatives always requires the use of a template anion (iodide, chloride or bromide) which is enclosed in the cavity of BU[6]. We show that this anion influences the reactivity of bambus[6]urils. An encapsulated iodide makes allyl functions of allyl12BU[6] less reactive towards TEC and hydrogenation reactions in comparison to the corresponding chloride or bromide inclusion complexes. This is critical for the chemical reactivity of BU[6] and even more to determine their anion-binding properties. We report a new, facile and fast method using AgSbF6 to prepare anion-free BU[6]. NMR methods were used to estimate association constants of these new empty BU[6] with different anions. Quantum chemistry calculations were employed to rationalize the observed results. These new functionalized bambusuril scaffolds in alternate conformation could find applications as multivalent binders. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The level of aryl acylamidase activity displayed by human butyrylcholinesterase depends on its molecular distribution.

PubMed

Montenegro, M F; Moral-Naranjo, M T; Páez de la Cadena, M; Campoy, F J; Muñoz-Delgado, E; Vidal, C J

2008-09-25

Butyrylcholinesterase (BuChE) and acetylcholinesterase (AChE) display both esterase and aryl acylamidase (AAA) activities. Their AAA activity can be measured using o-nitroacetanilide (ONA). In human samples depleted of acetylcholinesterase, we noticed that the ratio of amidase to esterase activities varied depending on the source, despite both activities being due to BuChE. Searching for an explanation, we compared the activities of BuChE molecular forms in samples of human colon, kidney and serum, and observed that BuChE monomers (G(1)) hydrolyzed o-nitroacetanilide much faster than tetramers (G(4)). This fact suggested that association might cause differences in the AAA site between single and polymerized subunits. This and other post-translational modifications in BuChE subunits probably determine their level of AAA activity. The higher amidase activity of monomers could justify the presence of single BuChE subunits in cells as a way to preserve the AAA activity of BuChE, which could be lost by oligomerization.

Vibrational relaxation and internal conversion in the overlapped optically-allowed 1Bu+ and optically-forbidden 1Bu- or 3Ag- vibronic levels of carotenoids: Effects of diabatic mixing as determined by Kerr-gate fluorescence spectroscopy

NASA Astrophysics Data System (ADS)

Kakitani, Yoshinori; Miki, Takeshi; Koyama, Yasushi; Nagae, Hiroyoshi; Nakamura, Ryosuke; Kanematsu, Yasuo

2009-07-01

The time constants of the vibrational relaxation, υ = 2 → υ = 1 and υ = 1 → υ = 0, in the 1Bu+ manifold and those of internal conversion from the 1Bu+(0) level, which is isoenergetic (so-called 'diabatic') with the 1Bu- vibronic levels in neurosporene and spheroidene and with the 3Ag- vibronic levels in lycopene and anhydrorhodovibrin, were determined by Kerr-gate fluorescence spectroscopy. The time constants of the vibrational relaxation were in the ˜1:2 ratio, and those of internal conversion agreed with the lifetimes of the diabatic counterparts, i.e., the 1Bu- and 3Ag- electronic states, respectively.

Epiplasmins and epiplasm in paramecium: the building of a submembraneous cytoskeleton.

PubMed

Aubusson-Fleury, Anne; Bricheux, Geneviève; Damaj, Raghida; Lemullois, Michel; Coffe, Gérard; Donnadieu, Florence; Koll, France; Viguès, Bernard; Bouchard, Philippe

2013-07-01

In ciliates, basal bodies and associated appendages are bound to a submembrane cytoskeleton. In Paramecium, this cytoskeleton takes the form of a thin dense layer, the epiplasm, segmented into regular territories, the units where basal bodies are inserted. Epiplasmins, the main component of the epiplasm, constitute a large family of 51 proteins distributed in 5 phylogenetic groups, each characterized by a specific molecular design. By GFP-tagging, we analyzed their differential localisation and role in epiplasm building and demonstrated that: 1) The epiplasmins display a low turnover, in agreement with the maintenance of an epiplasm layer throughout the cell cycle; 2) Regionalisation of proteins from different groups allows us to define rim, core, ring and basal body epiplasmins in the interphase cell; 3) Their dynamics allows definition of early and late epiplasmins, detected early versus late in the duplication process of the units. Epiplasmins from each group exhibit a specific combination of properties. Core and rim epiplasmins are required to build a unit; ring and basal body epiplasmins seem more dispensable, suggesting that they are not required for basal body docking. We propose a model of epiplasm unit assembly highlighting its implication in structural heredity in agreement with the evolutionary history of epiplasmins. Copyright © 2013 Elsevier GmbH. All rights reserved.

Synthesis, structure and reactivity of [Tm(Bu(t))]ZnH, a monomeric terminal zinc hydride compound in a sulfur-rich coordination environment: access to a heterobimetallic compound.

PubMed

Kreider-Mueller, Ava; Quinlivan, Patrick J; Rauch, Michael; Owen, Jonathan S; Parkin, Gerard

2016-02-07

The first terminal zinc hydride complex that features a sulfur-rich coordination environment, namely the tris(2-mercapto-1-tert-butylimidazolyl)hydroborato compound, [Tm(Bu(t))]ZnH, has been synthesized via the reaction of [Tm(Bu(t))]ZnOPh with PhSiH3. The Zn-H bond of [Tm(Bu(t))]ZnH is subject to insertion of CO2 and facile protolytic cleavage, of which the latter provides access to heterobimetallic [Tm(Bu(t))]ZnMo(CO)3Cp.

Prompt immune tolerance induction at inhibitor diagnosis regardless of titre may increase overall success in haemophilia A complicated by inhibitors: experience of two U.S. centres.

PubMed

Nakar, C; Manco-Johnson, M J; Lail, A; Donfield, S; Maahs, J; Chong, Y; Blades, T; Shapiro, A

2015-05-01

Current guidelines recommend delaying the start of immune tolerance induction (ITI) until the inhibitor titre is <10 Bethesda units (BU) to improve success. This study was conducted to evaluate ITI outcome relative to time to start ITI from inhibitor detection irrespective of inhibitor titre. Data were retrospectively collected from two U.S. haemophilia treatment centres (HTCs) on subjects with severe/moderate factor VIII (FVIII) deficiency with inhibitors who underwent ITI. Outcomes were defined pragmatically: success--negative inhibitor titre and ability to use FVIII concentrate for treatment/bleed prevention; partial success--inhibitor titre 1 to <5 BU with ability to use FVIII concentrate for treatment of bleeding; failure--ITI ongoing >3 years without achieving success/partial success, or ITI discontinuation. Fifty-eight subjects were included; 32 of 39 (82%) with high-responding inhibitor (HRI) achieved success, 7 failed. HRI subjects were subdivided based on ITI start time: 23/39 subjects started within 1 month of detection and 22/23 (96%) achieved success. Of these 23, 13 started ITI with an inhibitor titre ≥10 BU; all were successes. Eleven of 39 HRI subjects had an interval >6 months until ITI start; 7 (64%) achieved success. Time from inhibitor detection to ITI start may play a critical role in outcome. A titre ≥10 BU at ITI start did not influence outcome in subjects when ITI was initiated within 1 month of detection. Prompt ITI should be considered a viable therapeutic option in newly identified patients with inhibitors regardless of current inhibitor titre. © 2014 John Wiley & Sons Ltd.

Thiolate-bridged dinuclear iron(tris-carbonyl)–nickel complexes relevant to the active site of [NiFe] hydrogenase

PubMed Central

Ohki, Yasuhiro; Yasumura, Kazunari; Kuge, Katsuaki; Tanino, Soichiro; Ando, Masaru; Li, Zilong; Tatsumi, Kazuyuki

2008-01-01

The reaction of NiBr2(EtOH)4 with a 1:2–3 mixture of FeBr2(CO)4 and Na(SPh) generated a linear trinuclear Fe–Ni–Fe cluster (CO)3Fe(μ-SPh)3Ni(μ-SPh)3Fe(CO)3, 1, whereas the analogous reaction system FeBr2(CO)4/Na(StBu)/NiBr2(EtOH)4 (1:2–3:1) gave rise to a linear tetranuclear Fe–Ni–Ni–Fe cluster [(CO)3Fe(μ-StBu)3Ni(μ-Br)]2, 2. By using this tetranuclear cluster 2 as the precursor, we have developed a new synthetic route to a series of thiolate-bridged dinuclear Fe(CO)3–Ni complexes, the structures of which mimic [NiFe] hydrogenase active sites. The reactions of 2 with SC(NMe2)2 (tmtu), Na{S(CH2)2SMe} and ortho-NaS(C6H4)SR (R = Me, tBu) led to isolation of (CO)3Fe(μ-StBu)3NiBr(tmtu), 3, (CO)3Fe(StBu)(μ-StBu)2Ni{S(CH2)2SMe}, 4, and (CO)3Fe(StBu)(μ-StBu)2Ni{S(C6H4)SR}, 5a (R = Me) and 5b (R = tBu), respectively. On the other hand, treatment of 2 with 2-methylthio-phenolate (ortho-O(C6H4)SMe) in methanol resulted in (CO)3Fe(μ-StBu)3Ni(MeOH){O(C6H4)SMe}, 6a. The methanol molecule bound to Ni is labile and is readily released under reduced pressure to afford (CO)3Fe(StBu)(μ-StBu)2Ni{O(C6H4)SMe}, 6b, and the coordination geometry of nickel changes from octahedral to square planar. Likewise, the reaction of 2 with NaOAc in methanol followed by crystallization from THF gave (CO)3Fe(μ-StBu)3Ni(THF)(OAc), 7. The dinuclear complexes, 3-7, are thermally unstable, and a key to their successful isolation is to carry out the reactions and manipulations at −40°C. PMID:18511566

Resting State and Elementary Steps of the Coupling of Aryl Halides with Thiols Catalyzed by Alkylbisphosphine Complexes of Palladium

PubMed Central

Alvaro, Elsa

2010-01-01

Detailed mechanistic studies on the coupling of aryl halides with thiols catalyzed by palladium complexes of the alkylbisphosphine ligand CyPF-tBu (1-dicyclohexylphosphino-2-di-tert-butylphosphinoethylferrocene) are reported. The elementary steps that constitute the catalytic cycle, i.e. oxidative addition, transmetalation and reductive elimination, have been studied, and their relative rates are reported. Each of the steps of the catalytic process occurs at temperatures that are much lower than those required for the reactions catalyzed by a combination of palladium precursors and CyPF-tBu. To explain these differences in rates between the catalytic and stoichiometric reactions, studies were conducted to identify the resting state of the catalyst of the reactions catalyzed by a combination of Pd(OAc)2 and CyPF-tBu, a combination of Pd(dba)2 and CyPF-tBu, or the likely intermediate Pd(CyPF-tBu)(Ar)(Br). These show that the major palladium complex in each case lies off of the catalytic cycle. The resting state of the reactions catalyzed by Pd(OAc)2 and CyPF-tBu was the palladium bis-thiolate complex [Pd(CyPF-tBu)(SR)2] (R = alkyl or aryl). The resting state in reactions catalyzed by Pd2(dba)3 and CyPF-tBu was the binuclear complex [Pd(CyPF-tBu)]2(μ2, η2-dba) (9). The resting state of reactions of both aromatic and aliphatic thiols catalyzed by [Pd(CyPF-tBu)(p-tolyl)(Br)] (3a) was the hydridopalladium thiolate complex [Pd(CyPF-tBu)(H)(SR)] (R= alkyl and aryl). All these palladium species have been prepared independently, and the mechanisms by which they enter the catalytic cycle have been examined in detail. These features of the reaction catalyzed by palladium and CyPF-tBu have been compared with those of reactions catalyzed by the alkylbisphosphine DiPPF and Pd(OAc)2 or Pd(dba)2. Our data indicate that the resting states of these reactions are similar to each other and that our mechanistic conclusions about reactions catalyzed by palladium and CyPF-tBu can be extrapolated to reactions catalyzed by complexes of other electron-rich bisphosphines. PMID:19453106

Growth factor withdrawal in combination with sodium butyrate addition extends culture longevity and enhances antibody production in CHO cells.

PubMed

Hong, Jong Kwang; Lee, Gyun Min; Yoon, Sung Kwan

2011-09-10

The effect of growth factor (GF) and sodium butyrate (NaBu) on Chinese hamster ovary (CHO) cell growth, cell viability and antibody production was investigated using shaking flasks in GF-containing and GF-deficient medium containing 0, 1 and 3mM NaBu. The withdrawal of GF and the addition of NaBu suppressed cell growth, but they significantly increased specific antibody productivity, q(Ab). Interestingly, the withdrawal of GF in combination with the addition of NaBu markedly retarded cell death, leading to extended culture longevity. For instance, at 3mM NaBu, cell viability fell below 80% after day 4 in GF-containing medium, but it remained over 80% until day 18 in GF-deficient medium. Due to the enhanced q(Ab) and the extended culture longevity, approximately 2-fold increase in total antibody production was achieved in pseudo-perfusion culture with 1mM NaBu in GF-deficient medium, compared to the culture in GF-containing medium. The effect of GF and NaBu on the change in the expression and activity of cellular proteins, c-Myc, Bcl-2 and pyruvate dehydrogenase (PDH), was also investigated. Both the withdrawal of GF and the addition of NaBu decreased the expression of c-Myc. The expression of Bcl-2 was enhanced by the addition of NaBu in a dose-dependent manner while it was not affected by the withdrawal of GF. In addition, both the withdrawal of GF and the addition of NaBu reduced metabolic rates, q(Glc), q(Lac) and Y(Lac/Glc), and increased PDH activity while not affecting PDH expression, suggesting that they may reduce the glycolytic rates, but enhance the conversion rates of pyruvate to TCA intermediates. Taken together, the withdrawal of GF in combination with the addition of NaBu can be considered as a relevant strategy for alleviating NaBu-induced cell apoptosis and enhancing antibody production since it can be easily implemented as well as enhance q(Ab) and extend culture longevity. Copyright © 2011 Elsevier B.V. All rights reserved.

A Review of Butyrylcholinesterase as a Therapeutic Target in the Treatment of Alzheimer’s Disease

PubMed Central

Ballard, Clive; Bullock, Roger; Darreh-Shori, Taher; Somogyi, Monique

2013-01-01

Objective: To examine the role of butyrylcholinesterase (BuChE) in cholinergic signaling and neurologic conditions, such as Alzheimer’s disease (AD). The rationale for inhibiting cholinesterases in the management of AD, including clinical evidence supporting use of the dual acetylcholinesterase (AChE) and BuChE inhibitor rivastigmine, is discussed. Data Sources: PubMed searches were performed using butyrylcholinesterase as a keyword. English-language articles referenced in PubMed as of September 2011 were included. Study Selection and Data Synthesis: English-language articles related to BuChE considered to be of clinical relevance to physicians were included. English-language articles specifically related to AChE were not included, as the role of AChE in cholinergic signaling and the underlying pathology of AD is well documented. Reference lists of included publications were used to supplement the search. Results: AChE and BuChE play a role in cholinergic signaling; BuChE can hydrolyze acetylcholine and compensate for AChE when levels are depleted. In the AD brain, AChE levels decrease, while BuChE levels are reportedly increased or unchanged, with changes becoming more pronounced during the disease course. Furthermore, BuChE genotype may influence AD risk and rate of disease progression. Strategies that increase acetylcholine levels (eg, cholinesterase inhibitors) demonstrate symptomatic efficacy in AD. Rivastigmine has proven cognitive efficacy in clinical trials, and data suggest that its action is mediated, in part, by inhibition of BuChE. Retrospective analyses of clinical trials provide evidence that BuChE genotype may also influence treatment response. Conclusions: AChE-selective inhibitors and a dual AChE and BuChE inhibitor demonstrate symptomatic efficacy in AD. Mounting preclinical and clinical evidence for a role of BuChE in maintaining normal cholinergic function and the pathology of AD provides a rationale for further studies investigating use of rivastigmine in AD and the influence of BuChE genotype on observed efficacy. PMID:23930233

Synthesis, structure and reactivity of a terminal magnesium fluoride compound, [TpBut,Me]MgF: hydrogen bonding, halogen bonding and C-F bond formation.

PubMed

Rauch, Michael; Ruccolo, Serge; Mester, John Paul; Rong, Yi; Parkin, Gerard

2016-01-01

The bulky tris(3- tert -butyl-5-pyrazolyl)hydroborato ligand, [Tp Bu t ,Me ], has been employed to obtain the first structurally characterized example of a molecular magnesium compound that features a terminal fluoride ligand, namely [Tp Bu t ,Me ]MgF, via the reaction of [Tp Bu t ,Me ]MgMe with Me 3 SnF. The chloride, bromide and iodide complexes, [Tp Bu t ,Me ]MgX (X = Cl, Br, I), can also be obtained by an analogous method using Me 3 SnX. The molecular structures of the complete series of halide derivatives, [Tp Bu t ,Me ]MgX (X = F, Cl, Br, I) have been determined by X-ray diffraction. In each case, the Mg-X bond lengths are shorter than the sum of the covalent radii, thereby indicating that there is a significant ionic component to the bonding, in agreement with density functional theory calculations. The fluoride ligand of [Tp Bu t ,Me ]MgF undergoes halide exchange with Me 3 SiX (X = Cl, Br, I) to afford [Tp Bu t ,Me ]MgX and Me 3 SiF. The other halide derivatives [Tp Bu t ,Me ]MgX undergo similar exchange reactions, but the thermodynamic driving forces are much smaller than those involving fluoride transfer, a manifestation of the often discussed silaphilicity of fluorine. In accord with the highly polarized Mg-F bond, the fluoride ligand of [Tp Bu t ,Me ]MgF is capable of serving as a hydrogen bond and halogen bond acceptor, such that it forms adducts with indole and C 6 F 5 I. [Tp Bu t ,Me ]MgF also reacts with Ph 3 CCl to afford Ph 3 CF, thereby demonstrating that [Tp Bu t ,Me ]MgF may be used to form C-F bonds.

Flavin-containing monooxygenase 3 (FMO3) role in busulphan metabolic pathway

PubMed Central

Terelius, Ylva; Abedi-Valugerdi, Manuchehr; Naughton, Seán; Saghafian, Maryam; Moshfegh, Ali; Mattsson, Jonas; Potácová, Zuzana; Hassan, Moustapha

2017-01-01

Busulphan (Bu) is an alkylating agent used in the conditioning regimen prior to hematopoietic stem cell transplantation (HSCT). Bu is extensively metabolized in the liver via conjugations with glutathione to form the intermediate metabolite (sulfonium ion) which subsequently is degraded to tetrahydrothiophene (THT). THT was reported to be oxidized forming THT-1-oxide that is further oxidized to sulfolane and finally 3-hydroxysulfolane. However, the underlying mechanisms for the formation of these metabolites remain poorly understood. In the present study, we performed in vitro and in vivo investigations to elucidate the involvement of flavin-containing monooxygenase-3 (FMO3) and cytochrome P450 enzymes (CYPs) in Bu metabolic pathway. Rapid clearance of THT was observed when incubated with human liver microsomes. Furthermore, among different recombinant microsomal enzymes, the highest intrinsic clearance for THT was obtained via FMO3 followed by several CYPs including 2B6, 2C8, 2C9, 2C19, 2E1 and 3A4. In Bu- or THT-treated mice, inhibition of FMO3 by phenylthiourea significantly suppressed the clearance of both Bu and THT. Moreover, the simultaneous administration of a high dose of THT (200μmol/kg) to Bu-treated mice reduced the clearance of Bu. Consistently, in patients undergoing HSCT, repeated administration of Bu resulted in a significant up-regulation of FMO3 and glutathione-S-transfrase -1 (GSTA1) genes. Finally, in a Bu-treated patient, additional treatment with voriconazole (an antimycotic drug known as an FMO3-substrate) significantly altered the Bu clearance. In conclusion, we demonstrate for the first time that FMO3 along with CYPs contribute a major part in busulphan metabolic pathway and certainly can affect its kinetics. The present results have high clinical impact. Furthermore, these findings might be important for reducing the treatment-related toxicity of Bu, through avoiding interaction with other concomitant used drugs during conditioning and hence improving the clinical outcomes of HSCT. PMID:29121650

Flavin-containing monooxygenase 3 (FMO3) role in busulphan metabolic pathway.

PubMed

El-Serafi, Ibrahim; Terelius, Ylva; Abedi-Valugerdi, Manuchehr; Naughton, Seán; Saghafian, Maryam; Moshfegh, Ali; Mattsson, Jonas; Potácová, Zuzana; Hassan, Moustapha

2017-01-01

Busulphan (Bu) is an alkylating agent used in the conditioning regimen prior to hematopoietic stem cell transplantation (HSCT). Bu is extensively metabolized in the liver via conjugations with glutathione to form the intermediate metabolite (sulfonium ion) which subsequently is degraded to tetrahydrothiophene (THT). THT was reported to be oxidized forming THT-1-oxide that is further oxidized to sulfolane and finally 3-hydroxysulfolane. However, the underlying mechanisms for the formation of these metabolites remain poorly understood. In the present study, we performed in vitro and in vivo investigations to elucidate the involvement of flavin-containing monooxygenase-3 (FMO3) and cytochrome P450 enzymes (CYPs) in Bu metabolic pathway. Rapid clearance of THT was observed when incubated with human liver microsomes. Furthermore, among different recombinant microsomal enzymes, the highest intrinsic clearance for THT was obtained via FMO3 followed by several CYPs including 2B6, 2C8, 2C9, 2C19, 2E1 and 3A4. In Bu- or THT-treated mice, inhibition of FMO3 by phenylthiourea significantly suppressed the clearance of both Bu and THT. Moreover, the simultaneous administration of a high dose of THT (200μmol/kg) to Bu-treated mice reduced the clearance of Bu. Consistently, in patients undergoing HSCT, repeated administration of Bu resulted in a significant up-regulation of FMO3 and glutathione-S-transfrase -1 (GSTA1) genes. Finally, in a Bu-treated patient, additional treatment with voriconazole (an antimycotic drug known as an FMO3-substrate) significantly altered the Bu clearance. In conclusion, we demonstrate for the first time that FMO3 along with CYPs contribute a major part in busulphan metabolic pathway and certainly can affect its kinetics. The present results have high clinical impact. Furthermore, these findings might be important for reducing the treatment-related toxicity of Bu, through avoiding interaction with other concomitant used drugs during conditioning and hence improving the clinical outcomes of HSCT.

Discriminative stimulus effects of the imidazoline I2 receptor ligands BU224 and phenyzoline in rats.

PubMed

Qiu, Yanyan; Zhang, Yanan; Li, Jun-Xu

2015-02-15

Although imidazoline I2 receptor ligands have been used as discriminative stimuli, the role of efficacy of I2 receptor ligands as a critical determinant in drug discrimination has not been explored. This study characterized the discriminative stimulus effects of selective imidazoline I2 receptor ligands BU224 (a low-efficacy I2 receptor ligand) and phenyzoline (a higher efficacy I2 receptor ligand) in rats. Two groups of male Sprague-Dawley rats were trained to discriminate 5.6mg/kg BU224 or 32mg/kg phenyzoline (i.p.) from their vehicle in a two-lever food-reinforced drug discrimination procedure, respectively. All rats acquired the discriminations after an average of 18 (BU224) and 56 (phenyzoline) training sessions, respectively. BU224 and phenyzoline completely substituted for one another symmetrically. Several I2 receptor ligands (tracizoline, CR4056, RS45041, and idazoxan) all occasioned>80% drug-associated lever responding in both discriminations. The I2 receptor ligand 2-BFI and a monoamine oxidase inhibitor harmane occasioned>80% drug-associated lever responding in rats discriminating BU224. Other drugs that occasioned partial or less substitution to BU224 cue included clonidine, methamphetamine, ketamine, morphine, methadone and agmatine. Clonidine, methamphetamine and morphine also only produced partial substitution to phenyzoline cue. Naltrexone, dopamine D2 receptor antagonist haloperidol and serotonin (5-HT)2A receptor antagonist MDL100907 failed to alter the discriminative stimulus effects of BU224 or phenyzoline. Combined, these results are the first to demonstrate that BU224 and phenyzoline can serve as discriminative stimuli and that the low-efficacy I2 receptor ligand BU224 shares similar discriminative stimulus effects with higher-efficacy I2 receptor ligands such as phenyzoline and 2-BFI. Copyright © 2015 Elsevier B.V. All rights reserved.

Different Cholinesterase Inhibitor Effects on CSF Cholinesterases in Alzheimer Patients

PubMed Central

Nordberg, Agneta; Darreh-Shori, Taher; Peskind, Elaine; Soininen, Hilkka; Mousavi, Malahat; Eagle, Gina; Lane, Roger

2014-01-01

Background The current study aimed to compare the effects of different cholinesterase inhibitors on acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activities and protein levels, in the cerebrospinal fluid (CSF) of Alzheimer disease (AD) patients. Methods and Findings AD patients aged 50–85 years were randomized to open-label treatment with oral rivastigmine, donepezil or galantamine for 13 weeks. AChE and BuChE activities were assayed by Ellman’s colorimetric method. Protein levels were assessed by enzyme-linked immunosorbent assay (ELISA). Primary analyses were based on the Completer population (randomized patients who completed Week 13 assessments). 63 patients were randomized to treatment. Rivastigmine was associated with decreased AChE activity by 42.6% and decreased AChE protein levels by 9.3%, and decreased BuChE activity by 45.6% and decreased BuChE protein levels by 21.8%. Galantamine decreased AChE activity by 2.1% and BuChE activity by 0.5%, but increased AChE protein levels by 51.2% and BuChE protein levels by10.5%. Donepezil increased AChE and BuChE activities by 11.8% and 2.8%, respectively. Donepezil caused a 215.2%increase in AChE and 0.4% increase in BuChE protein levels. Changes in mean AChE-Readthrough/Synaptic ratios, which might reflect underlying neurodegenerative processes, were 1.4, 0.6, and 0.4 for rivastigmine, donepezil and galantamine, respectively. Conclusion The findings suggest pharmacologically-induced differences between rivastigmine, donepezil and galantamine. Rivastigmine provides sustained inhibition of AChE and BuChE, while donepezil and galantamine do not inhibit BuChE and are associated with increases in CSF AChE protein levels. The clinical implications require evaluation. PMID:19199870

Different cholinesterase inhibitor effects on CSF cholinesterases in Alzheimer patients.

PubMed

Nordberg, Agneta; Darreh-Shori, Taher; Peskind, Elaine; Soininen, Hilkka; Mousavi, Malahat; Eagle, Gina; Lane, Roger

2009-02-01

The current study aimed to compare the effects of different cholinesterase inhibitors on acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activities and protein levels, in the cerebrospinal fluid (CSF) of Alzheimer disease (AD) patients. AD patients aged 50-85 years were randomized to open-label treatment with oral rivastigmine, donepezil or galantamine for 13 weeks. AChE and BuChE activities were assayed by Ellman's colorimetric method. Protein levels were assessed by enzyme-linked immunosorbent assay (ELISA). Primary analyses were based on the Completer population (randomized patients who completed Week 13 assessments). 63 patients were randomized to treatment. Rivastigmine was associated with decreased AChE activity by 42.6% and decreased AChE protein levels by 9.3%, and decreased BuChE activity by 45.6% and decreased BuChE protein levels by 21.8%. Galantamine decreased AChE activity by 2.1% and BuChE activity by 0.5%, but increased AChE protein levels by 51.2% and BuChE protein levels by 10.5%. Donepezil increased AChE and BuChE activities by 11.8% and 2.8%, respectively. Donepezil caused a 215.2% increase in AChE and 0.4% increase in BuChE protein levels. Changes in mean AChE-Readthrough/Synaptic ratios, which might reflect underlying neurodegenerative processes, were 1.4, 0.6, and 0.4 for rivastigmine, donepezil and galantamine, respectively. The findings suggest pharmacologically-induced differences between rivastigmine, donepezil and galantamine. Rivastigmine provides sustained inhibition of AChE and BuChE, while donepezil and galantamine do not inhibit BuChE and are associated with increases in CSF AChE protein levels. The clinical implications require evaluation.

Follicle-stimulating hormone receptor-mediated uptake of sup 45 Ca sup 2+ by cultured rat Sertoli cells does not require activation of cholera toxin- or pertussis toxin-sensitive guanine nucleotide binding proteins or adenylate cyclase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grasso, P.; Reichert, L.E. Jr.

1990-08-01

We have previously reported that FSH stimulates flux of 45Ca2+ into cultured Sertoli cells from immature rats via voltage-sensitive and voltage-independent calcium channels. In the present study, we show that this effect of FSH does not require cholera toxin (CT)- or pertussis toxin (PT)-sensitive guanine nucleotide binding (G) protein or activation of adenylate cyclase (AC). Significant stimulation of 45Ca2+ influx was observed within 1 min, and maximal response (3.2-fold over basal levels) was achieved within 2 min after exposure to FSH. FSH-stimulated elevations in cellular cAMP paralleled increases in 45Ca2+ uptake, suggesting a possible coupling of AC activation to 45Ca2+more » influx. (Bu)2cAMP, however, was not able to enhance 45Ca2+ uptake over basal levels at a final concentration of 1000 microM, although a concentration-related increase in androstenedione conversion to estradiol was evident. Exposure of Sertoli cells to CT (10 ng/ml) consistently stimulated basal levels of androstenedione conversion to estradiol but had no effect on basal levels of 45Ca2+ uptake. Similarly, CT had no effect on FSH-induced 45Ca2+ uptake, but potentiated FSH-stimulated estradiol synthesis. PT (10 ng/ml) augmented basal and FSH-stimulated estradiol secretion without affecting 45Ca2+ influx. The adenosine analog N6-phenylisopropyladenosine, which binds to Gi-coupled adenosine receptors on Sertoli cells, inhibited FSH-stimulated androgen conversion to estradiol in a dose-related (1-1000 nM) manner, but FSH-stimulated 45Ca2+ influx remained unchanged. Our results show that in contrast to FSH-stimulated estradiol synthesis, the flux of 45Ca2+ into Sertoli cells in response to FSH is not mediated either directly or indirectly by CT- or PT-sensitive G protein, nor does it require activation of AC. Our data further suggest that the FSH receptor itself may function as a calcium channel.« less

Singlet internal conversion processes in the order of 1Bu+→3Ag-→1Bu-→2Ag-→1Ag- in all- trans-spheroidene and lycopene as revealed by subpicosecond time-resolved Raman spectroscopy

NASA Astrophysics Data System (ADS)

Rondonuwu, Ferdy S.; Kakitani, Yoshinori; Tamura, Hiroshi; Koyama, Yasushi

2006-09-01

Key Raman lines ascribable to the 1Bu+, 3Ag-, 1Bu- and 2Ag- states were identified in the subpicosecond time-resolved Raman spectra of spheroidene and lycopene having 10 and 11 conjugated double bonds, respectively. The sequential rise-and-decay of the key Raman lines showed the internal conversion processes of 1Bu+→3Ag-→1Bu-→2Ag-→1Ag- (ground). The time constant in each step of internal conversion reflects the energy gap between the relevant states that had been determined by measurement of resonance - Raman excitation profiles [K. Furuichi, T. Sashima, Y. Koyama, Chem. Phys. Lett. 356 (2002) 547].

Mitogenic activity of a water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii. IV. Synergistic effects of Bu-WSA on Concanavalin A-induced proliferative response of human peripheral blood lymphocytes.

PubMed

Nitta, T; Okumura, S; Tsushi, M; Nakano, M

1982-01-01

Butanol-extracted water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii was cultured with peripheral blood mononuclear cells (PBM) in the presence of sub- and/or supra-optimal mitogenic concentrations of concanavalin A (Con A). The addition of Bu-WSA resulted in increased tritiated thymidine incorporation above that produced by Con A alone. Bu-WSA by itself is not mitogenic for PBM and in fact produced a decrease in thymidine uptake compared to the control. We investigated the response of subpopulation(s) of PBM to Bu-WSA, Con A and a mixture of Bu-WSA and Con A. Separation of PBM into purified T cells, B cells and macrophages showed that cell-cell cooperation of T cells with B cells or macrophages is necessary for the observed synergistic effect of Bu-WSA with Con A. A marked increase in thymidine incorporation by the mixture of T and B cell populations occurred, while only a small amount of thymidine was incorporated when the B cell population was absent. Mitomycin treatment revealed that the response could be ascribed to the T-cell response with a B-cell helper effect. Moreover, Con A and Bu-WSA appeared to act on the same T cell population. This model may provide unique information about the activation of human peripheral blood T cells compared with the activation of these cells by other mitogens.

Conditioning with Fludarabine-Busulfan versus Busulfan-Cyclophosphamide Is Associated with Lower aGVHD and Higher Survival but More Extensive and Long Standing Bone Marrow Damage

PubMed Central

Ye, YongBin; Wang, Jing; Huang, YuXian; Weng, GuangYang; Zhang, MingWan

2016-01-01

Acute graft-versus-host disease (aGVHD) is a major complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT) and a major cause of nonrelapse mortality after allo-HSCT. A conditioning regimen plays a pivotal role in the development of aGVHD. To provide a platform for studying aGVHD and evaluating the impact of different conditioning regimens, we established a murine aGVHD model that simulates the clinical situation and can be conditioned with Busulfan-Cyclophosphamide (Bu-Cy) and Fludarabine-Busulfan (Flu-Bu). In our study, BALB/c mice were conditioned with Bu-Cy or Flu-Bu and transplanted with 2 × 107 bone marrow cells and 2 × 107 splenocytes from either allogeneic (C57BL/6) or syngeneic (BALB/c) donors. The allogeneic recipients conditioned with Bu-Cy had shorter survivals (P < 0.05), more severe clinical manifestations, and higher hepatic and intestinal pathology scores, associated with increased INF-γ expression and diminished IL-4 expression in serum, compared to allogeneic recipients conditioned with Flu-Bu. Moreover, higher donor-derived T-cell infiltration and severely impaired B-cell development were seen in the bone marrow of mice, exhibiting aGVHD and conditioned with Flu-Bu. Our study showed that the conditioning regimen with Bu-Cy resulted in more severe aGVHD while the Flu-Bu regimen was associated with more extensive and long standing bone marrow damage. PMID:27843940

Bis(O-n-butyl dithio­carbonato-κ2 S,S′)bis­(pyridine-κN)manganese(II)

PubMed Central

Alam, Naveed; Ehsan, Muhammad Ali; Zeller, Matthias; Mazhar, Muhammad; Arifin, Zainudin

2011-01-01

The structure of the title manganese complex, [Mn(C5H9OS2)2(C5H5N)2] or [Mn(S2CO-n-Bu)2(C5H5N)2], consists of discrete monomeric entities with Mn2+ ions located on centres of inversion. The metal atom is coordinated by a six-coordinate trans-N2S4 donor set with the pyridyl N atoms located in the apical positions. The observed slight deviations from octa­hedral geometry are caused by the bite angle of the bidentate κ2-S2CO-n-Bu ligands [69.48 (1)°]. The O(CH2)3(CH3) chains of the O-n-butyl dithio­carbonate units are disordered over two sets of sites with an occupancy ratio of 0.589 (2):0.411 (2). PMID:22090847

Bis(O-n-butyl dithio-carbonato-κS,S')bis-(pyridine-κN)manganese(II).

PubMed

Alam, Naveed; Ehsan, Muhammad Ali; Zeller, Matthias; Mazhar, Muhammad; Arifin, Zainudin

2011-08-01

The structure of the title manganese complex, [Mn(C(5)H(9)OS(2))(2)(C(5)H(5)N)(2)] or [Mn(S(2)CO-n-Bu)(2)(C(5)H(5)N)(2)], consists of discrete monomeric entities with Mn(2+) ions located on centres of inversion. The metal atom is coordinated by a six-coordinate trans-N(2)S(4) donor set with the pyridyl N atoms located in the apical positions. The observed slight deviations from octa-hedral geometry are caused by the bite angle of the bidentate κ(2)-S(2)CO-n-Bu ligands [69.48 (1)°]. The O(CH(2))(3)(CH(3)) chains of the O-n-butyl dithio-carbonate units are disordered over two sets of sites with an occupancy ratio of 0.589 (2):0.411 (2).

NMR Kinetics of the S[subscript N]2 Reaction between BuBr and I[superscript -]: An Introductory Organic Chemistry Laboratory Exercise

ERIC Educational Resources Information Center

Mobley, T. Andrew

2015-01-01

A simple organic chemistry experiment is described that investigates the kinetics of the reaction between 1-bromobutane (BuBr) and iodide (I[superscript -]) as followed by observing the disappearance of BuBr and the appearance of 1-iodobutane (BuI) using [superscript 1]H NMR spectroscopy. In small groups of three to four, students acquire data to…

Butyrate-induced proapoptotic and antiangiogenic pathways in EAT cells require activation of CAD and downregulation of VEGF

DOE Office of Scientific and Technical Information (OSTI.GOV)

Belakavadi, Madesh; Prabhakar, B.T.; Salimath, Bharathi P.

Butyrate, a short-chain fatty acid produced in the colon, induces cell cycle arrest, differentiation, and apoptosis in transformed cell lines. In this report, we study the effects of butyrate (BuA) on the growth of Ehrlich ascites tumor (EAT) cells in vivo. BuA, when injected intraperitoneally (i.p) into mice, inhibited proliferation of EAT cells. Further, induction of apoptosis in EAT cells was monitored by nuclear condensation, annexin-V staining, DNA fragmentation, and translocation of caspase-activated DNase into nucleus upon BuA-treatment. Ac-DEVD-CHO, a caspase-3 inhibitor, completely inhibited BuA-induced apoptosis, indicating that activation of caspase-3 mediates the apoptotic pathway in EAT cells. The proapoptoticmore » effect of BuA also reflects on the antiangiogenic pathway in EAT cells. The antiangiogenic effect of BuA in vivo was demonstrated by the downregulation of the secretion of VEGF in EAT cells. CD31 immunohistochemical staining of peritoneum sections clearly indicated a potential angioinhibitory effect of BuA in EAT cells. These results suggest that BuA, besides regulating other fundamental cellular processes, is able to modulate the expression/secretion of the key angiogenic growth factor VEGF in EAT cells.« less

Human butyrylcholinesterase components differ in aryl acylamidase activity.

PubMed

Montenegro, María F; María, T Moral-Naranjo; de la Cadena, María Páez; Campoy, Francisco J; Muñoz-Delgado, Encarnación; Vidal, Cecilio J

2008-04-01

Apart from its esterase activity, butyrylcholinesterase (BuChE) displays aryl acylamidase (AAA) activity able to hydrolyze o-nitroacetanilide (ONA) and its trifluoro-derivative (F-ONA). We report here that, despite amidase and esterase sites residing in the same protein, in human samples depleted of acetylcholinesterase the ratio of amidase to esterase activity varied depending on the source of BuChE. The much faster degradation of ONA and F-ONA by BuChE monomers (G1) of colon and kidney than by the tetramers (G4) suggests aggregation-driven differences in the AAA site between single and polymerized subunits. The similar ratio of F-ONAto butyrylthiocholine hydrolysis by serum G1 and G4 forms support structural differences in the amidase site according to the source of BuChE. The changing ratios of amidase to esterase activities in the human sources probably arise from post-translational modifications in BuChE subunits, the specific proportion of monomers and oligomers and the variable capacity of the tetramers for degrading ONA and F-ONA. The elevated amidase activity of BuChE monomers and the scant activity of the tetramers justify the occurrence of single BuChE subunits in cells as a means to sustain the AAA activity of BuChE which otherwise could be lost by tetramerization.

The Generic Structure Potential of Science Nonfiction Selections in Four Basal Reading Series, Grades One and Two

ERIC Educational Resources Information Center

Anthony, Angela Beckman

2009-01-01

Basal reading series are used in a majority of classrooms in the United States. The purpose of this study was to examine the frequency of fiction and nonfiction genres included in four recently published first and second grade basal reading series and to compare the frequencies to studies of older basal reading series. Based on the work of…

IR Spectra of n-Bu4M (M = Si, Ge, Sn, Pb), n-BuAuPPh3-d15, and "n-Bu" on a Gold Surface.

PubMed

Kaleta, Jiří; Bednárová, Lucie; Čížková, Martina; Wen, Jin; Kaletová, Eva; Michl, Josef

2017-06-22

Observed and DFT-calculated IR spectra of n-Bu 4 M (M = Si, Ge, Sn, Pb), (CH 3 CH 2 CH 2 13 CD 2 ) 4 Sn, and n-BuAuPPh 3 -d 15 are reported and assigned. The asymmetric CH stretching vibration of the CH 2 group adjacent to the metal atom appears as a distinct shoulder at ∼2934 cm -1 , whereas for other CH 2 groups it is located at ∼2922 cm -1 . The characteristic peak at ∼2899 cm -1 is attributed to an overtone of a symmetric CH 2 bend at ∼1445 cm -1 . In n-BuAuPPh 3 -d 15 , the CH stretching vibrations of the butyl group are shifted to lower frequencies by ∼10 cm -1 , and two possible rationalizations are offered.

One-Electron Oxidation of [M(P(t) Bu3 )2 ] (M=Pd, Pt): Isolation of Monomeric [Pd(P(t) Bu3 )2 ](+) and Redox-Promoted C-H Bond Cyclometalation.

PubMed

Troadec, Thibault; Tan, Sze-Yin; Wedge, Christopher J; Rourke, Jonathan P; Unwin, Patrick R; Chaplin, Adrian B

2016-03-07

Oxidation of zero-valent phosphine complexes [M(P(t) Bu3 )2 ] (M=Pd, Pt) has been investigated in 1,2-difluorobenzene solution using cyclic voltammetry and subsequently using the ferrocenium cation as a chemical redox agent. In the case of palladium, a mononuclear paramagnetic Pd(I) derivative was readily isolated from solution and fully characterized (EPR, X-ray crystallography). While in situ electrochemical measurements are consistent with initial one-electron oxidation, the heavier congener undergoes C-H bond cyclometalation and ultimately affords the 14 valence-electron Pt(II) complex [Pt(κ(2) PC -P(t) Bu2 CMe2 CH2 )(P(t) Bu3 )](+) with concomitant formation of [Pt(P(t) Bu3 )2 H](+) . © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

The thermodynamic characteristics of solutions of Bu4NI in dimethylsulfoxide over a wide concentration range

NASA Astrophysics Data System (ADS)

Safonova, L. P.; Shmukler, L. E.; Kolker, A. M.

2008-05-01

The integral heats of solution of Bu4NI in dimethylsulfoxide (DMSO) were measured at 298.15, 313.15, and 328.15 K and concentrations from dilute to saturation. The standard enthalpies and heat capacities of solution and solvation of Bu4NI in DMSO at various temperatures and the bar C_p^o (Bu_4 N^ + ) value at 298.15 K were calculated. The obtained and literature data were used to consider the influence of the nature of solvents on Δsol H m (Bu4NI) and of the electrolyte on Δsol H m in dimethylsulfoxide at 298.15 K. The dynamic viscosity and density of the Bu4NI-DMSO system were determined at various concentrations and temperatures. The Eyring equation was used to calculate the activation energy of viscous flow at all the concentrations studied.

Clarifying the butter Boletes: a new genus, Butyriboletus, is established to accommodate Boletus sect. Appendiculati, and six new species are described.

PubMed

Arora, David; Frank, Jonathan L

2014-01-01

The butter boletes (Boletus s.l. sect. Appendiculati) are an economically important group of ectomycorrhizal fungi whose basidiocarps have a yellow tube layer that often bruises blue, yellow reticulate stipe, mild flavor and firm yellow-tinged flesh that may or may not turn blue when exposed. Morphological characters and molecular data (ITS and LSU) place this group in a separate phylogenetic clade from Boletus sensu stricto. Here we establish a new genus, Butyriboletus, to accommodate 14 species of butter boletes that range from Asia to Europe, north Africa and North America. We recombine eight previously described butter bolete species and we describe six new species: four from western USA (Bu. persolidus, Bu. primiregius, Bu. autumnigius, Bu. querciregius) and two from Yunnan, China (Bu. yicibus, Bu. sanicibus). © 2014 by The Mycological Society of America.

Crystal Structure and Theoretical Analysis of Green Gold Au 30 (S- t Bu) 18 Nanomolecules and Their Relation to Au 30 S(S- t Bu) 18

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dass, Amala; Jones, Tanya; Rambukwella, Milan

We report the complete X-ray crystallographic structure as determined through single crystal X-ray diffraction and a thorough theoretical analysis of the green gold Au30(S-tBu)18. While the structure of Au30S(S-tBu)18 with 19 sulfur atoms has been reported, the crystal structure of Au30(S-tBu)18 without the μ3-sulfur has remained elusive until now, though matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) and electrospray ionization mass spectrometry (ESI-MS) data unequivocally shows its presence in abundance. The Au30(S-tBu)18 nanomolecule is not only distinct in its crystal structure but has unique temperature dependent optical properties. Structure determination allows a rigorous comparison and an excellent agreement with theoreticalmore » predictions of structure, stability, and optical response.« less

Constructing a Catalytic Cycle for C-F to C-X (X = O, S, N) Bond Transformation Based on Gold-Mediated Ligand Nucleophilic Attack.

PubMed

Hu, Ji-Yun; Zhang, Jing; Wang, Gao-Xiang; Sun, Hao-Ling; Zhang, Jun-Long

2016-03-07

A tricoordinated gold(I) chloride complex, tBuXantphosAuCl, supported by a sterically bulky 9,9-dimethyl-4,5-bis(di-tert-butylphosphino)xanthene ligand (tBuXantphos) was synthesized. This complex features a remarkably longer Au-Cl bond length [2.632(1) Å] than bicoordinated linear gold complexes (2.27-2.30 Å) and tricoordinated XantphosAuCl [2.462(1) Å]. Single-crystal X-ray diffraction analysis of a cocrystal of tBuXantphosAuCl and pentafluoronitrobenzene (PFNB) and UV-vis spectroscopic titration experiments revealed the existence of an anion-π interaction between the Cl anion ligand and PFNB. Stoichiometric reaction between PFNB and tBuXantphosAuOtBu, after replacement of Cl by a more nucleophilic tBuO anion ligand, showed higher reactivity and para selectivity in the transformation of C-F to C-OtBu bond, distinctively different from that when only KOtBu was used (ortho selectivity) under the identical condition. Mechanistic studies including density functional theory calculations suggested a gold-mediated nucleophilic ligand attack of the C-F bond pathway via an SNAr process. On the basis of these results, using trimethylsilyl derivatives TMS-X (X = OMe, SEt, NEt2) as the nucleophilic ligand source and the fluorine acceptor, catalytic transformation of the C-F bond of aromatic substrates to the C-X (X = O, S, N) bond was achieved with tBuXantphosAuCl as the catalyst (up to 20 turnover numbers).

Mitogenic Activity of a Water-Soluble Adjuvant (Bu-WSA) Obtained from Bacterionema matruchotii: IV. Synergistic Effects of Bu-WSA on Concanavalin A-Induced Proliferative Response of Human Peripheral Blood Lymphocytes.

PubMed

Nitta, Toshimasa; Okumura, Seiichi; Tsushi, Masao; Nakano, Masayasu

1982-07-01

Butanol-extracted water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii was cultured with peripheral blood mononuclear cells (PBM) in the presence of sub- and/or supra-optimal mitogenic concentrations of concanavalin A (Con A). The addition of Bu-WSA resulted in increased tritiated thymidine incorporation above that produced by Con A alone. Bu-WSA by itself is not mitogenic for PBM and in fact produced a decrease in thymidine uptake compared to the control. We investigated the response of subpopulation(s) of PBM to Bu-WSA, Con A and a mixture of Bu-WSA and Con A. Separation of PBM into purified T cells, B cells and macrophages showed that cell-cell cooperation of T cells with B cells or macrophages is necessary for the observed synergistic effect of Bu-WSA with Con A. A marked increase in thymidine incorporation by the mixture of T and B cell populations occurred, while only a small amount of thymidine was incorporated when the B cell population was absent. Mitomycin treatment revealed that the response could be ascribed to the T-cell response with a B-cell helper effect. Moreover, Con A and Bu-WSA appeared to act on the same T cell population. This model may provide unique information about the activation of human peripheral blood T cells compared with the activation of these cells by other mitogens. © owned by Center for Academic Publications Japan (Publisher).

A Landscape-based model for predicting Mycobacterium ulcerans infection (Buruli Ulcer disease) presence in Benin, West Africa.

PubMed

Wagner, Tyler; Benbow, M Eric; Burns, Meghan; Johnson, R Christian; Merritt, Richard W; Qi, Jiaguo; Small, Pamela L C

2008-03-01

Mycobacterium ulcerans infection (Buruli ulcer [BU] disease) is an emerging tropical disease that causes severe morbidity in many communities, especially those in close proximity to aquatic environments. Research and control efforts are severely hampered by the paucity of data regarding the ecology of this disease; for example, the vectors and modes of transmission remain unknown. It is hypothesized that BU presence is associated with altered landscapes that perturb aquatic ecosystems; however, this has yet to be quantified over large spatial scales. We quantified relationships between land use/land cover (LULC) characteristics surrounding individual villages and BU presence in Benin, West Africa. We also examined the effects of other village-level characteristics which we hypothesized to affect BU presence, such as village distance to the nearest river. We found that as the percent urban land use in a 50-km buffer surrounding a village increased, the probability of BU presence decreased. Conversely, as the percent agricultural land use in a 20-km buffer surrounding a village increased, the probability of BU presence increased. Landscape-based models had predictive ability when predicting BU presence using validation data sets from Benin and Ghana, West Africa. Our analyses suggest that relatively small amounts of urbanization are associated with a decrease in the probability of BU presence, and we hypothesize that this is due to the increased availability of pumped water in urban environments. Our models provide an initial approach to predicting the probability of BU presence over large spatial scales in Benin and Ghana, using readily available land use data.

Family relationship, water contact and occurrence of Buruli ulcer in Benin.

PubMed

Sopoh, Ghislain Emmanuel; Barogui, Yves Thierry; Johnson, Roch Christian; Dossou, Ange Dodji; Makoutodé, Michel; Anagonou, Sévérin Y; Kestens, Luc; Portaels, Françoise

2010-07-13

Mycobacterium ulcerans disease (Buruli ulcer) is the most widespread mycobacterial disease in the world after leprosy and tuberculosis. How M. ulcerans is introduced into the skin of humans remains unclear, but it appears that individuals living in the same environment may have different susceptibilities. This study aims to determine whether frequent contacts with natural water sources, family relationship or the practice of consanguineous marriages are associated with the occurrence of Buruli ulcer (BU). Case control study. Department of Atlantique, Benin. BU-confirmed cases that were diagnosed and followed up at the BU detection and treatment center (CDTUB) of Allada (Department of the Atlantique, Benin) during the period from January 1st, 2006, to June 30th, 2008, with three matched controls (persons who had no signs or symptoms of active or inactive BU) for age, gender and village of residence per case. Contact with natural water sources, BU history in the family and the practice of consanguineous marriages. A total of 416 participants were included in this study, including 104 cases and 312 controls. BU history in the family (p<0.001), adjusted by daily contact with a natural water source (p = 0.007), was significantly associated with higher odds of having BU (OR; 95% CI = 5.5; 3.0-10.0). The practice of consanguineous marriage was not associated with the occurrence of BU (p = 0.40). Mendelian disorders could explain this finding, which may influence individual susceptibility by impairing immunity. This study suggests that a combination of genetic factors and behavioral risk factors may increase the susceptibility for developing BU.

[A comparison of toxicity and efficacy between busulfan plus fludarabine and busulfan plus cyclophosphamide for allogeneic hematopoietic stem cell transplantation in acute myeloid leukemia].

PubMed

Liu, Hui; Fan, Zhi-ping; Jiang, Qian-li; Huang, Fen; Zhou, Hong-sheng; Zhang, Xian; Yu, Guo-pan; Wu, Mei-qing; Sun, Jing; Liu, Qi-fa

2012-11-01

To compare the transplant-related toxicity and the efficacy of busulfan/fludarabine (Bu/Flu) and busulfan/cyclophosphamide (Bu/Cy) as conditioning regimen in allogeneic hematopoietic stem cell transplantation (allo-HSCT) for acute myeloid leukemia(AML) in the first complete remission (CR1). Totally 32 AML-CR1 patients underwent allo-HSCT were divided into Bu/Cy (Bu 3.2 mg×kg(-1)×d(-1), 7 - 4 days before transplantation; Cy 60 mg×kg(-1)×d(-1), 3 - 2 days before transplantation) and Bu/Flu (Bu 3.2 mg×kg(-1)×d(-1), 5 - 2 days before transplantation; Flu 30 mg×m(-2)×d(-1), 6 - 2 days before transplantation) groups. The regimen-related toxicity (RRT), incidence and severity of graft-versus-host disease (GVHD), 3-year cumulative relapse rate, non-relapse mortality (NRM), 3-year event-free survival (EFS) rate and overall survival (OS) rate were compared between the two groups. The median follow-up duration was 617.5 (6 - 1261) days. All patients achieved successful engraftment on 30 day after transplantation. There were no significant differences in the median time to neutrophil engraftment (P = 0.121) and platelet engraftment (P = 0.171) between the two groups. The median duration of neutrophil count under 0.1×10(9)/L and platelet count under 20×10(9)/L in the Bu/Cy group were significantly longer than those in the Bu/Flu group (P = 0.000 and P = 0.047). The incidence of grades II-IV RRT were 68.8% and 25.0% (P = 0.032) in the Bu/Cy and the Bu/Flu groups, respectively. There were no significant differences in the incidence of acute GVHD (P = 0.149), chronic GVHD (P = 0.149), incidence of NRM (P = 0.333), 3-year cumulative relapse rates (P = 0.834), 3-year EFS rate (P = 0.362) and OS rate (P = 0.111) between the two groups. Compared with Bu/Cy, Bu/Flu is a myeloablative condition regimen with milder bone marrow suppression and lower RRT incidence rate in allogeneic HSCT for AML-CR1 patients without compromising the efficacy.

Flavones from Erythrina falcata are modulators of fear memory.

PubMed

de Oliveira, Daniela Rodrigues; Zamberlam, Cláudia R; Gaiardo, Renan Barreta; Rêgo, Gizelda Maia; Cerutti, Janete M; Cavalheiro, Alberto J; Cerutti, Suzete M

2014-08-05

Flavonoids, which have been identified in a variety of plants, have been demonstrated to elicit beneficial effects on memory. Some studies have reported that flavonoids derived from Erythrina plants can provide such beneficial effects on memory. The aim of this study was to identify the flavonoids present in the stem bark crude extract of Erythrina falcata (CE) and to perform a bioactivity-guided study on conditioned fear memory. The secondary metabolites of CE were identified by high performance liquid chromatography combined with a diode array detector, electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI/MSn) and nuclear magnetic resonance (NMR). The buthanolic fraction (BuF) was obtained by partitioning. Subfractions from BuF (BuF1 - BuF6) and fraction flavonoidic (FfA and FfB) were obtained by flash chromatography. The BuF3 and BuF4 fractions were used for the isolation of flavonoids, which was performed using HPLC-PAD. The isolated substances were quantified by HPLC-DAD and their structures were confirmed by nuclear magnetic resonance (NMR). The activities of CE and the subfractions were monitored using a one-trial, step-down inhibitory avoidance (IA) task to identify the effects of these substances on the acquisition and extinction of conditioned fear in rats. Six subclasses of flavonoids were identified for the first time in CE. According to our behavioral data, CE, BuF, BuF3 and BuF4, the flavonoidic fractions, vitexin, isovitexin and 6-C-glycoside-diosmetin improved the acquisition of fear memory. Rats treated with BuF, BuF3 and BuF4 were particularly resistant to extinction. Nevertheless, rats treated with FfA and FfB, vitexin, isovitexin and 6-C-glycoside-diosmetin exhibited gradual reduction in conditioned fear response during the extinction retest session, which was measured at 48 to 480 h after conditioning. Our results demonstrate that vitexin, isovitexin and diosmetin-6-C-glucoside and flavonoidic fractions resulted in a significant retention of fear memory but did not prevent the extinction of fear memory. These results further substantiate that the treatment with pure flavonoids or flavanoid-rich fractions might represent potential therapeutic approaches for the treatment of neurocognitive disorders, improvement of memory acquisition and spontaneous recovery of fear.

Chasma Boreale in the North Polar Region

NASA Technical Reports Server (NTRS)

2006-01-01

This images shows a Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) full-resolution 'targeted image' of the edge of Mars' north polar cap. The region in the image, Chasma Boreale, is a valley several kilometers or miles deep that cuts about 400 kilometers (about 250 miles) into the edge of the cap.

This image was acquired at 0851 UTC (4:51 a.m. EDT) on Oct. 1, 2006, near 84.6 degrees north latitude, 3.6 degrees east longitude. It covers an area about 13 kilometers (8 miles) long and, at the narrowest point, about 9 kilometers (5.6 miles) wide. At the center of the image the spatial resolution is as good as 18 meters (60 feet) per pixel. The image was taken in 544 colors covering wavelengths of 0.36 to 3.92 micrometers. Two renderings of the data are shown here, both draped over topography without vertical exaggeration, and then viewed from a perspective diagonally above the site. The top view is an approximately true-color representation. The bottom view, constructed from infrared wavelengths, shows strength of the spectral signature of ice. Brighter areas are rich in ice, and dark areas have little ice.

The polar cap has long been recognized to contain layers composed of dust and ice, and hence has been named the polar layered deposit. This sits atop an underlying 'basal unit.' The upper part of the basal unit is dark at visible wavelengths and steeply sloped, whereas the lower part of the basal unit is brighter, redder, and layered like the polar layered deposits. The chasma floor is cratered, and in the foreground it is covered by dunes that are outliers of a north polar sand sea that surrounds the polar cap. The polar layered deposits and the basal unit form a steeply sloping scarp about 1.1 kilometers (0.7 miles) high.

CRISM's image of this region shows a number of previously unrecognized characteristics of the polar layered deposits and the basal unit. First, the ice-rich polar layered deposits exhibit coherent banding both at visible and infrared wavelengths. This banding shows a history of differences in the abundance of dust that accumulated in polar ice, differences in ice grain size, or both. Second, both parts of the basal unit are depleted in ice, except for triangle-shaped regions on the side of the scarp. Third, the spectral properties of the brighter, layered lower basal unit resemble those of the polar layered deposits. In contrast, the upper basal unit is distinct from both of them. Finally, spectral properties of the foreground dunes closely resemble those of the darkest layers within the upper basal unit, and may be debris from it.

CRISM is one of six science instruments on NASA's Mars Reconnaissance Orbiter. Led by The Johns Hopkins University Applied Physics Laboratory, the CRISM team includes expertise from universities, government agencies and small businesses in the United States and abroad.

CRISM's mission: Find the spectral fingerprints of aqueous and hydrothermal deposits and map the geology, composition and stratigraphy of surface features. The instrument will also watch the seasonal variations in Martian dust and ice aerosols, and water content in surface materials -- leading to new understanding of the climate.

NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Reconnaissance Orbiter mission for the NASA Science Mission Directorate. Lockheed Martin Space Systems, Denver, is the prime contractor and built the spacecraft.

Preclinical evaluation of a novel cyanine dye for tumor imaging with in vivo photoacoustic imaging.

PubMed

Temma, Takashi; Onoe, Satoru; Kanazaki, Kengo; Ono, Masahiro; Saji, Hideo

2014-09-01

Photoacoustic imaging (PA imaging or PAI) has shown great promise in the detection and monitoring of cancer. Although nanocarrier-based contrast agents have been studied for use in PAI, small molecule contrast agents are required due to their ease of preparation, costeffectiveness, and low toxicity. Here, we evaluated the usefulness of a novel cyanine dye IC7-1-Bu as a PAI contrast agent without conjugated targeting moieties for in vivo tumor imaging in a mice model. Basic PA characteristics of IC7-1-Bu were compared with indocyanine green (ICG), a Food and Drug Administration approved dye, in an aqueous solution. We evaluated the tumor accumulation profile of IC7-1-Bu and ICG by in vivo fluorescence imaging. In vivo PAI was then performed with a photoacoustic tomography system 24 and 48 h after intravenous injection of IC7-1-Bu into tumor bearing mice. IC7-1-Bu showed about a 2.3-fold higher PA signal in aqueous solution compared with that of ICG. Unlike ICG, IC7-1-Bu showed high tumor fluorescence after intravenous injection. In vivo PAI provided a tumor to background PA signal ratio of approximately 2.5 after intravenous injection of IC7-1-Bu. These results indicate that IC7-1-Bu is a promising PAI contrast agent for cancer imaging without conjugation of targeting moieties.

Reactivation of Plasma Butyrylcholinesterase by Pralidoxime Chloride in Patients Poisoned by WHO Class II Toxicity Organophosphorus Insecticides

PubMed Central

Eddleston, Michael

2013-01-01

Some clinicians assess the efficacy of pralidoxime in organophosphorus (OP) poisoned patients by measuring reactivation of butyrylcholinesterase (BuChE). However, the degree of BuChE inhibition varies by OP insecticide, and it is unclear how well oximes reactivate BuChE in vivo. We aimed to assess the usefulness of BuChE activity to monitor pralidoxime treatment by studying its reactivation after pralidoxime administration to patients with laboratory-proven World Health Organization (WHO) class II OP insecticide poisoning. Patient data were derived from 2 studies, a cohort study (using a bolus treatment of 1g pralidoxime chloride) and a randomized controlled trial (RCT) (comparing 2g pralidoxime over 20min, followed by an infusion of 0.5g/h, with placebo). Two grams of pralidoxime variably reactivated BuChE in patients poisoned by 2 diethyl OP insecticides, chlorpyrifos and quinalphos; however, unlike acetylcholinesterase reactivation, this reactivation was not sustained. It did not reactivate BuChE inhibited by the dimethyl OPs dimethoate or fenthion. The 1-g dose produced no reactivation. Pralidoxime produced variable reactivation of BuChE in WHO class II OP-poisoned patients according to the pralidoxime dose administered, OP ingested, and individual patient. The use of BuChE assays for monitoring the effect of pralidoxime treatment is unlikely to be clinically useful. PMID:24052565

Household cost of out-patient treatment of Buruli ulcer in Ghana: a case study of Obom in Ga South Municipality

PubMed Central

2013-01-01

Background The economic burden of diseases has become increasingly relevant to policy makers as healthcare expenditure keep rising in the face of limited and competing resources. Buruli ulcer (BU), a neglected but treatable tropical disease caused by Mycobacterium ulcerans, the only known environmental mycobacterium is capable of causing long term disability when left untreated. However, most BU studies have tended to focused on its bacteriology, epidemiology, entomology and other social determinants to the neglect of its economic evaluation. This paper reports estimated the household economic costs of BU and describe the intangible cost suffered by BU patients in an endemic area. Methods Retrospective one year cost data was used. A total of 63 confirmed BU cases were randomly sampled for the study. Economic cost and cost burden of BU were estimated. Sensitivity analysis was conducted to test the robustness of the cost estimates. Intangible cost measured stigmatization, pain, functional limitation and social isolation of children. Results The annual total household economic cost was US$35,915.98, of which about 65% was cost incurred by children with a mean cost of US$521.04. The mean annual household cost was US$570.09. The direct cost was 96% of the total cost. Non-medical cost accounts for about 97% of the direct cost with a mean cost of US$529.27. The mean medical cost was US$18.94. The main cost drivers of the household costs were transportation (78%) and food (12%). Caregivers and adult patients lost a total of 535 productive days seeking care, which gives an indirect cost valued at US$1,378.67 with a mean of US$21.88. A total of 365 school days (about 1 year) were lost by 19 BU patients (mean, 19.2 days). Functional loss and pain were low, and stigma rated moderate. Most children suffering from BU (84%) were socially isolated. Conclusion Household cost burden of out-patient BU ulcer treatment was high. Household cost of BU is therefore essential in the design of its intervention. BU afflicted children experience social isolation. PMID:24313975

Predictions of BuChE inhibitors using support vector machine and naive Bayesian classification techniques in drug discovery.

PubMed

Fang, Jiansong; Yang, Ranyao; Gao, Li; Zhou, Dan; Yang, Shengqian; Liu, Ai-Lin; Du, Guan-hua

2013-11-25

Butyrylcholinesterase (BuChE, EC 3.1.1.8) is an important pharmacological target for Alzheimer's disease (AD) treatment. However, the currently available BuChE inhibitor screening assays are expensive, labor-intensive, and compound-dependent. It is necessary to develop robust in silico methods to predict the activities of BuChE inhibitors for the lead identification. In this investigation, support vector machine (SVM) models and naive Bayesian models were built to discriminate BuChE inhibitors (BuChEIs) from the noninhibitors. Each molecule was initially represented in 1870 structural descriptors (1235 from ADRIANA.Code, 334 from MOE, and 301 from Discovery studio). Correlation analysis and stepwise variable selection method were applied to figure out activity-related descriptors for prediction models. Additionally, structural fingerprint descriptors were added to improve the predictive ability of models, which were measured by cross-validation, a test set validation with 1001 compounds and an external test set validation with 317 diverse chemicals. The best two models gave Matthews correlation coefficient of 0.9551 and 0.9550 for the test set and 0.9132 and 0.9221 for the external test set. To demonstrate the practical applicability of the models in virtual screening, we screened an in-house data set with 3601 compounds, and 30 compounds were selected for further bioactivity assay. The assay results showed that 10 out of 30 compounds exerted significant BuChE inhibitory activities with IC50 values ranging from 0.32 to 22.22 μM, at which three new scaffolds as BuChE inhibitors were identified for the first time. To our best knowledge, this is the first report on BuChE inhibitors using machine learning approaches. The models generated from SVM and naive Bayesian approaches successfully predicted BuChE inhibitors. The study proved the feasibility of a new method for predicting bioactivities of ligands and discovering novel lead compounds.

The rs662 polymorphism of paraoxonase 1 affects the difference in the inhibition of butyrylcholinesterase activity by organophosphorus pesticides in human blood.

PubMed

Nam, Dae Cheol; Ha, Yu Mi; Park, Min Kyu; Cho, Sung Kweon

2016-08-01

Organophosphorus pesticides (OPs) are a human health hazard. OPs inhibit acetylcholinesterase (AChE) at nerve endings and accumulate acetylcholine (ACh) at these sites. High levels of ACh and long exposure promote cholinergic crisis. The hydrolysis of OPs by serum paraoxonase 1 (PON1) plays a role in cholinergic crisis in humans. Human serum PON1 can break down organophosphate before binding to ChE. We investigated the effect of PON1 polymorphisms on AChE activity after OP treatment. 50 healthy volunteers were randomly recruited with informed consent. We investigated butyrylcholinesterase (BuChE) activity changes in plasma as a biomarker of AChE after OP treatment in human blood samples immediately following blood sampling. After the standardization of BuChE activity in human blood, we correlated changes in BuChE activity with changes in blood pH. We analyzed the PON1 polymorphisms (rs854560 and rs662) of 50 participants to retrospectively investigate the interindividual variability of changes in BuChE activity. Changes in BuChE activity are strongly correlated with pH changes after OP treatment (R2 = 0.913). We used changes in pH as a surrogate marker for BuChE inhibition after OP treatment. OP treatment significantly decreased BuChE activity by 56.4 ± 5.1% (p < 0.001). The degree of BuChE inhibition was significantly different in the PON1 rs662 genotype (56.10 ± 4.74% vs. 57.96 ± 5.67% vs. 52.34 ± 1.51%; GG vs. GA vs. AA, respectively). Changes in pH can be used as a surrogate marker for the detection of BuChE inhibition after OP exposure. The rs662 polymorphism of PON1 may explain the inter-individual variability in BuChE inhibition.

Metabolism and elimination of methyl, iso- and n-butyl paraben in human urine after single oral dosage.

PubMed

Moos, Rebecca K; Angerer, Jürgen; Dierkes, Georg; Brüning, Thomas; Koch, Holger M

2016-11-01

Parabens are used as preservatives in personal care and consumer products, food and pharmaceuticals. Their use is controversial because of possible endocrine disrupting properties. In this study, we investigated metabolism and urinary excretion of methyl paraben (MeP), iso-butyl paraben (iso-BuP) and n-butyl paraben (n-BuP) after oral dosage of deuterium-labeled analogs (10 mg). Each volunteer received one dosage per investigated paraben separately and at least 2 weeks apart. Consecutive urine samples were collected over 48 h. In addition to the parent parabens (free and conjugated) which are already used as biomarkers of internal exposure and the known but non-specific metabolites, p-hydroxybenzoic acid (PHBA) and p-hydroxyhippuric acid (PHHA), we identified new, oxidized metabolites with hydroxy groups on the alkyl side chain (3OH-n-BuP and 2OH-iso-BuP) and species with oxidative modifications on the aromatic ring. MeP represented 17.4 % of the dose excreted in urine, while iso-BuP represented only 6.8 % and n-BuP 5.6 %. Additionally, for iso-BuP, about 16 % was excreted as 2OH-iso-BuP and for n-BuP about 6 % as 3OH-n-BuP. Less than 1 % was excreted as ring-hydroxylated metabolites. In all cases, PHHA was identified as the major but non-specific metabolite (57.2-63.8 %). PHBA represented 3.0-7.2 %. For all parabens, the majority of the oral dose captured by the above metabolites was excreted in the first 24 h (80.5-85.3 %). Complementary to the parent parabens excreted in urine, alkyl-chain-oxidized metabolites of the butyl parabens are introduced as valuable and contamination-free biomarkers of exposure.

Ethnopharmacological reports on anti-Buruli ulcer medicinal plants in three West African countries.

PubMed

Tsouh Fokou, Patrick Valere; Nyarko, Alexander Kwadwo; Appiah-Opong, Regina; Tchokouaha Yamthe, Lauve Rachel; Addo, Phyllis; Asante, Isaac K; Boyom, Fabrice Fekam

2015-08-22

Buruli ulcer (BU) is the third most common mycobacterial infection in the world, after tuberculosis and leprosy and has recently been recognized as an important emerging disease. This disease is common in West Africa where more than 99% of the burden is felt and where most affected people live in remote areas with traditional medicine as primary or only option. Reports indicate that the ethnopharmacological control approach of the disease in such settings has shown promise. However, no or very few compilations of traditional knowledge in using medicinal plants to treat BU have been attempted so far. This review aimed to record medicinal plants used traditionally against BU in three countries in West Africa: Ivory Coast, Ghana and Benin and for which ethnopharmacological knowledge supported by pharmacological investigations has been reported. The information recorded in this review will support further pharmacological research to develop appropriate drugs for a better BU control. A systematic review of the literature on ethnobotanical use and anti-BU activity of plants reported for BU treatment was performed. The approach consisted to search several resources, including Technical Reports, Books, Theses, Conference proceedings, web-based scientific databases such as publications on PubMed, Science direct, Springer, ACS, Scielo, PROTA, Google and Google scholar reporting ethnobotanical surveys and screening of natural products against Mycobacterium ulcerans. This study was limited to papers and documents published either in English or French reporting ethnopharmacological knowledge in BU treatment or pharmacological potency in vitro. This review covered the available literature up to December 2014. The majority of reports originated from the three most affected West African countries (Cote d'Ivoire, Ghana and Benin). Though, 98 plant species belonging to 48 families have been identified as having anti-BU use, many have received no or little attention. Most of the pharmacological studies were performed only on 54 species. To a lesser extent, ethnopharmacological knowledge was validated in vitro for only 13 species. Of those, seven species including Ricinus comminus, Cyperus cyperoides (cited as Mariscus alternifolius), Nicotiana tabacum, Mangifera indica, Solanum rugosum, Carica papaya, and Moringa oleifera demonstrated efficacy in hospitalised BU patients. Four isolated and characterized compounds were reported to have moderate bioactivity in vitro against M. ulcerans. This review compiles for the first time ethnopharmacologically useful plants against BU. The phamacological potential of 13 of them has been demonstrated in vitro and support BU evidence-based traditional medicines. In addition, 7 species showed activity in BU patients and have emerged as a promising source of the traditional medicine for treatment of BU. Yet, further safety and efficacy study should be initiated prior any approval as alternative therapy. Overall, a huge gap in knowledge appeared, suggesting further well-planned and detailed investigations of the in vitro, in vivo, and safety properties of the claimed anti-BU plants. Therefore, plants with medicinal potential should be scrutinized for biologically active compounds, using bioassay-guided fractionation approach to provide new insights to find novel therapeutics for BU control. Copyright © 2015. Published by Elsevier Ireland Ltd.

Geographic Distribution, Age Pattern and Sites of Lesions in a Cohort of Buruli Ulcer Patients from the Mapé Basin of Cameroon

PubMed Central

Bratschi, Martin W.; Bolz, Miriam; Minyem, Jacques C.; Grize, Leticia; Wantong, Fidèle G.; Kerber, Sarah; Njih Tabah, Earnest; Ruf, Marie-Thérèse; Mou, Ferdinand; Noumen, Djeunga; Um Boock, Alphonse; Pluschke, Gerd

2013-01-01

Buruli ulcer (BU), a neglected tropical disease of the skin, caused by Mycobacterium ulcerans, occurs most frequently in children in West Africa. Risk factors for BU include proximity to slow flowing water, poor wound care and not wearing protective clothing. Man-made alterations of the environment have been suggested to lead to increased BU incidence. M. ulcerans DNA has been detected in the environment, water bugs and recently also in mosquitoes. Despite these findings, the mode of transmission of BU remains poorly understood and both transmission by insects or direct inoculation from contaminated environment have been suggested. Here, we investigated the BU epidemiology in the Mapé basin of Cameroon where the damming of the Mapé River since 1988 is believed to have increased the incidence of BU. Through a house-by-house survey in spring 2010, which also examined the local population for leprosy and yaws, and continued surveillance thereafter, we identified, till June 2012, altogether 88 RT-PCR positive cases of BU. We found that the age adjusted cumulative incidence of BU was highest in young teenagers and in individuals above the age of 50 and that very young children (<5) were underrepresented among cases. BU lesions clustered around the ankles and at the back of the elbows. This pattern neither matches any of the published mosquito biting site patterns, nor the published distribution of small skin injuries in children, where lesions on the knees are much more frequent. The option of multiple modes of transmission should thus be considered. Analyzing the geographic distribution of cases in the Mapé Dam area revealed a closer association with the Mbam River than with the artificial lake. PMID:23785529

Comparison of Cyclophosphamide Combined with Total Body Irradiation, Oral Busulfan, or Intravenous Busulfan for Allogeneic Hematopoietic Cell Transplantation in Adults with Acute Lymphoblastic Leukemia.

PubMed

Mitsuhashi, Kenjiro; Kako, Shinichi; Shigematsu, Akio; Atsuta, Yoshiko; Doki, Noriko; Fukuda, Takahiro; Kanamori, Heiwa; Onizuka, Makoto; Takahashi, Satoshi; Ozawa, Yukiyasu; Kurokawa, Mineo; Inoue, Yoshiko; Nagamura-Inoue, Tokiko; Morishima, Yasuo; Mizuta, Shuichi; Tanaka, Junji

2016-12-01

We conducted a retrospective analysis to compare outcomes in adult patients with acute lymphoblastic leukemia (ALL) who underwent allogeneic hematopoietic cell transplantation (allo-HCT) with conditioning regimens containing cyclophosphamide (CY) in combination with total body irradiation (TBI), oral busulfan (p.o. BU), or intravenous busulfan (i.v. BU). We used data for January 2000 to December 2012 from the Transplant Registry Unified Management Program of the Japan Society of Hematopoietic Cell Transplantation. We identified 2130 patients treated with TBI/CY (n = 2028), p.o. BU/CY (n = 60), or i.v. BU/CY (n = 42). Two-year overall survival (OS) and 2-year relapse-free survival rates were 69.0% and 62.1%, respectively, in the TBI/CY group, 55.9% and 54.2% in the p.o. BU/CY group, and 71.0% and 46.8% in the i.v. BU/CY group. In multivariate analysis, compared with TBI/CY, p.o. BU/CY, but not i.v. BU/CY, was associated with lower OS (hazard ratio [HR], 1.46; P = .047) and a higher incidence of sinusoidal obstruction syndrome (HR, 3.36; P = .030). No between-group differences were seen in the incidence of nonrelapse mortality, relapse, acute graft-versus-host disease (GVHD), or chronic GVHD. We suggest that i.v. BU/CY might be a possible alternative allo-HCT conditioning regimen for adults with ALL who are not suitable for TBI. Copyright © 2016 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Gender-related differences in circadian rhythm of rat plasma acetyl- and butyrylcholinesterase: effects of sex hormone withdrawal.

PubMed

Alves-Amaral, Gracielle; Pires-Oliveira, Marcelo; Andrade-Lopes, Ana Luiza; Chiavegatti, Tiago; Godinho, Rosely Oliveira

2010-06-07

The role of acetylcholinesterase (AChE) in the termination of the cholinergic response through acetylcholine (ACh) hydrolysis and the involvement of plasma butyrylcholinesterase (BuChE), mainly of hepatic origin, in the metabolism of xenobiotics with ester bonds is well known. Besides, BuChE has a crucial role in ACh hydrolysis, especially when selective anticholinesterases inhibit AChE. Herein, we analyzed the gender-related differences and the circadian changes of rat plasma cholinesterases. Plasma and liver cholinesterase activities were evaluated in control or 2-30-day castrated adult male and female rats. Plasma and liver AChE activities did not differ between genders and were not influenced by sex hormone deprivation. BuChE plasma activity was 7 times greater in female, reflecting gender differences in liver enzyme expression. Castration increased liver and plasma BuChE activity in male, while reduced it in female, abolishing gender differences in enzyme activity. Interestingly, female AChE and BuChE plasma activities varied throughout the day, reaching values 27% and 42% lower, respectively, between 2 p.m. and 6 p.m. when compared to the morning peaks at 8 a.m. Castration attenuated daily female BuChE oscillation. On the other hand, male plasma enzymes remained constant throughout the day. In summary, our results show that liver and plasma BuChE, but not AChE, expression is influenced by sex hormones, leading to high levels of blood BuChE in females. The fluctuation of female plasma BuChE during the day should be taken into account to adjust the bioavailability and the therapeutic effects of cholinesterase inhibitors used in cholinergic-based conditions such Alzheimer's disease. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Occupational determinants of serum cholinesterase inhibition among organophosphate-exposed agricultural pesticide handlers in Washington State

PubMed Central

Hofmann, Jonathan N; Keifer, Matthew C; De Roos, Anneclaire J; Fenske, Richard A; Furlong, Clement E; van Belle, Gerald; Checkoway, Harvey

2010-01-01

Objective To identify potential risk factors for serum cholinesterase (BuChE) inhibition among agricultural pesticide handlers exposed to organophosphate (OP) and N-methyl-carbamate (CB) insecticides. Methods We conducted a longitudinal study among 154 agricultural pesticide handlers who participated in the Washington State cholinesterase monitoring program in 2006 and 2007. BuChE inhibition was analyzed in relation to reported exposures before and after adjustment for potential confounders using linear regression. Odds ratios estimating the risk of ‘BuChE depression’ (>20% from baseline) were also calculated for selected exposures based on unconditional logistic regression analyses. Results An overall decrease in mean BuChE activity was observed among study participants at the time of follow-up testing during the OP/CB spray season relative to pre-season baseline levels (mean decrease of 5.6%, P < 0.001). Score for estimated cumulative exposure to OP/CB insecticides in the past 30 days was a significant predictor of BuChE inhibition (β = −1.74, P < 0.001). Several specific work practices and workplace conditions were associated with greater BuChE inhibition, including mixing/loading pesticides and cleaning spray equipment. Factors that were protective against BuChE inhibition included full-face respirator use, wearing chemical-resistant boots, and storing personal protective equipment in a locker at work. Conclusions Despite existing regulations, agricultural pesticide handlers continue to be exposed to OP/CB insecticides at levels resulting in BuChE inhibition. These findings suggest that modifying certain work practices could potentially reduce BuChE inhibition. Replication from other studies will be valuable. PMID:19819864

Participation of interleukins in synergistic effect of Bu-WSA on concanavalin A-induced DNA synthesis in mouse splenic lymphocytes.

PubMed

Nitta, T; Konno-Ejiri, H; Nemoto, K; Okumura, S; Ozawa, A; Nakano, M

1986-09-01

Butanol-extracted water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii was mitogenic to murine splenic B lymphocytes, but not T lymphocytes. When murine splenic cells were cultured in the presence of Bu-WSA and concanavalin A (Con A) together, [3H]thymidine uptake of the culture cells synergically increased. The mechanism of the synergy of Con A and Bu-WSA and the participation of interleukin (IL) 1 and 2 in the synergy were studied. The proliferation cells in the synergy were Lyt-1+23- lymphocytes. Ia-positive accessory cells were required for the response. When separated cell populations and Marbrook-type culture vessels were used, a mixed cell population of T lymphocytes and B lymphocytes or macrophages (M phi) produced some active factor(s) after co-stimulation by Con A and Bu-WSA, and the factors enhanced DNA synthesis of another Con A-activated T lymphocyte population. Supernatants obtained from the spleen cell cultures or the mixed cell cultures with T lymphocytes and M phi in the presence of Con A and Bu-WSA contained greater amounts of IL-1 and IL-2 than those from cultures containing Con A or Bu-WSA alone. An addition of exogenous IL-1 or IL-2 to spleen cell cultures with Con A resulted in a proliferative response like that obtained through co-stimulation by Con A and Bu-WSA. These results suggest that the synergistic effect of Con A and Bu-WSA on the proliferative response in murine splenic cells is sustained by the enhancement of production of these T-lymphocyte growth factors.

Genetic diversity of Staphylococcus aureus in Buruli ulcer.

PubMed

Amissah, Nana Ama; Glasner, Corinna; Ablordey, Anthony; Tetteh, Caitlin S; Kotey, Nana Konama; Prah, Isaac; van der Werf, Tjip S; Rossen, John W; van Dijl, Jan Maarten; Stienstra, Ymkje

2015-02-01

Buruli ulcer (BU) is a necrotizing skin disease caused by Mycobacterium ulcerans. Previous studies have shown that wounds of BU patients are colonized with M. ulcerans and several other microorganisms, including Staphylococcus aureus, which may interfere with wound healing. The present study was therefore aimed at investigating the diversity and topography of S. aureus colonizing BU patients during treatment. We investigated the presence, diversity, and spatio-temporal distribution of S. aureus in 30 confirmed BU patients from Ghana during treatment. S. aureus was isolated from nose and wound swabs, and by replica plating of wound dressings collected bi-weekly from patients. S. aureus isolates were characterized by multiple-locus variable number tandem repeat fingerprinting (MLVF) and spa-typing, and antibiotic susceptibility was tested. Nineteen (63%) of the 30 BU patients tested positive for S. aureus at least once during the sampling period, yielding 407 S. aureus isolates. Detailed analysis of 91 isolates grouped these isolates into 13 MLVF clusters and 13 spa-types. Five (26%) S. aureus-positive BU patients carried the same S. aureus genotype in their anterior nares and wounds. S. aureus isolates from the wounds of seven (37%) patients were distributed over two different MLVF clusters. Wounds of three (16%) patients were colonized with isolates belonging to two different genotypes at the same time, and five (26%) patients were colonized with different S. aureus types over time. Five (17%) of the 30 included BU patients tested positive for methicillin-resistant S. aureus (MRSA). The present study showed that the wounds of many BU patients were contaminated with S. aureus, and that many BU patients from the different communities carried the same S. aureus genotype during treatment. This calls for improved wound care and hygiene.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tseng, F.Y.; Rani, C.S.; Field, J.B.

Since iodide (I-) inhibits TSH stimulation of cAMP formation, which mediates most of the effects of the hormone, it has been assumed that this accounts for the inhibitory action of iodide on the thyroid. However, TSH stimulation of 32P incorporation into phospholipids and stimulation of thyroid metabolism by other agonists, such as carbachol, phorbol esters, and ionophore A23187, is not cAMP mediated. The present studies examined the effect of iodide on stimulation of glucose oxidation and 32P incorporation into phospholipids by TSH and other agonists to determine if the inhibition of cAMP formation was responsible for the action of iodide.more » Preincubation of dog thyroid slices for 1 h with iodide (10(-4) M) inhibited TSH-, (Bu)2cAMP-, carbachol-, methylene blue-, 12-O-tetradecanoyl phorbol-13-acetate-, ionophore A23187-, prostaglandin E1-, and cholera toxin-stimulated glucose oxidation. I- also inhibited the stimulation by TSH, 12-O-tetradecanoyl phorbol-13-acetate, carbachol, and ionophore A23187 of 32P incorporation into phospholipids. The inhibition was similar whether iodide was added 2 h before or simultaneously with the agonist. I- itself sometimes stimulated basal glucose oxidation, but had no effect on basal 32P incorporation into phospholipids. The effects of iodide on basal and agonist-stimulated thyroid metabolism were blocked by methimazole (10(-3) M). When dog thyroid slices were preloaded with 32PO4 or (1-14C)glucose, the iodide inhibition of agonist stimulation disappeared, suggesting that the effect of iodide involves the transport process. In conclusion, I- inhibited stimulation of glucose oxidation and 32P incorporation into phospholipids by all agonists, indicating that the effect is independent of the cAMP system and that iodide autoregulation does not only involve this system. Oxidation and organification of iodide are necessary for the inhibition.« less

Dioxygen activation by non-adiabatic oxidative addition to a single metal center [O 2 activation by non-adiabatic oxidative addition to a single metal center

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akturk, Eser S.; Yap, Glenn P. A.; Theopold, Klaus H.

2015-10-16

A chromium(I) dinitrogen complex reacts rapidly with O 2 to form the mononuclear dioxo complex [Tp tBu,MeCr V(O) 2] (Tp tBu,Me=hydrotris(3- tert-butyl-5-methylpyrazolyl)borate), whereas the analogous reaction with sulfur stops at the persulfido complex [Tp tBu,MeCr III(S 2)]. The transformation of the putative peroxo intermediate [Tp tBu,MeCr III(O 2)] (S= 3/ 2) into [Tp tBu,MeCr V(O) 2] (S= 1/ 2) is spin-forbidden. The minimum-energy crossing point for the two potential energy surfaces has been identified. Finally, although the dinuclear complex [(Tp tBu,MeCr) 2(μ-O) 2] exists, mechanistic experiments suggest that O 2 activation occurs on a single metal center, by an oxidativemore » addition on the quartet surface followed by crossover to the doublet surface.« less

Influence on Busilvex pharmacokinetics of clonazepam compared to previous phenytoin historical data.

PubMed

Carreras, E; Cahn, J Y; Puozzo, C; Kröger, N; Sanz, G; Buzyn, A; Bacigalupo, A; Vernant, J P

2010-07-01

This study investigated the effect of seizure prophylaxis on busulfan (Bu) plasma exposure. Twenty-four adult patients received an intravenous Bu-cyclophoshamide conditioning regimen prior to bone marrow transplantation. Busilvex (0.8 mg/kg) was administered every six hours during four consecutive days. Clonazepam (0.025 to 0.03 mg/kg/day as a continuous 12-h i.v. infusion) was administered at least 12 hours prior to i.v. Bu dosing and continued until 24 hours after the last dose. Pharmacokinetic (PK) data were compared with those previously collected in patients (n=127) treated with phenytoin for seizure prophylaxis. Through population PK analysis, a 10% average increase (coefficient of variation, RSE=5.35%) in total clearance of Bu was quantified when Bu was associated with clonazepam as compared to phenytoin, which was considered as not being clinically relevant. The suspected induction on Bu metabolism by phenytoin should have resulted in the opposite effect. The patient efficacy and safety profiles were comparable between the two cohorts.

Implementation of a decentralized community-based treatment program to improve the management of Buruli ulcer in the Ouinhi district of Benin, West Africa

PubMed Central

Amoussouhoui, Arnaud Setondji; Wadagni, Anita Carolle; Johnson, Roch Christian; Aoulou, Paulin; Agbo, Inès Elvire; Houezo, Jean-Gabin; Boyer, Micah; Nichter, Mark

2018-01-01

Background Mycobacterium ulcerans infection, commonly known as Buruli ulcer (BU), is a debilitating neglected tropical disease. Its management remains complex and has three main components: antibiotic treatment combining rifampicin and streptomycin for 56 days, wound dressings and skin grafts for large ulcerations, and physical therapy to prevent functional limitations after care. In Benin, BU patient care is being integrated into the government health system. In this paper, we report on an innovative pilot program designed to introduce BU decentralization in Ouinhi district, one of Benin’s most endemic districts previously served by centralized hospital-based care. Methodology/Principal findings We conducted intervention-oriented research implemented in four steps: baseline study, training of health district clinical staff, outreach education, outcome and impact assessments. Study results demonstrated that early BU lesions (71% of all detected cases) could be treated in the community following outreach education, and that most of the afflicted were willing to accept decentralized treatment. Ninety-three percent were successfully treated with antibiotics alone. The impact evaluation found that community confidence in decentralized BU care was greatly enhanced by clinic staff who came to be seen as having expertise in the care of most chronic wounds. Conclusions/Significance This study documents a successful BU outreach and decentralized care program reaching early BU cases not previously treated by a proactive centralized BU program. The pilot program further demonstrates the added value of integrated wound management for NTD control. PMID:29529087

Implementation of a decentralized community-based treatment program to improve the management of Buruli ulcer in the Ouinhi district of Benin, West Africa.

PubMed

Amoussouhoui, Arnaud Setondji; Sopoh, Ghislain Emmanuel; Wadagni, Anita Carolle; Johnson, Roch Christian; Aoulou, Paulin; Agbo, Inès Elvire; Houezo, Jean-Gabin; Boyer, Micah; Nichter, Mark

2018-03-01

Mycobacterium ulcerans infection, commonly known as Buruli ulcer (BU), is a debilitating neglected tropical disease. Its management remains complex and has three main components: antibiotic treatment combining rifampicin and streptomycin for 56 days, wound dressings and skin grafts for large ulcerations, and physical therapy to prevent functional limitations after care. In Benin, BU patient care is being integrated into the government health system. In this paper, we report on an innovative pilot program designed to introduce BU decentralization in Ouinhi district, one of Benin's most endemic districts previously served by centralized hospital-based care. We conducted intervention-oriented research implemented in four steps: baseline study, training of health district clinical staff, outreach education, outcome and impact assessments. Study results demonstrated that early BU lesions (71% of all detected cases) could be treated in the community following outreach education, and that most of the afflicted were willing to accept decentralized treatment. Ninety-three percent were successfully treated with antibiotics alone. The impact evaluation found that community confidence in decentralized BU care was greatly enhanced by clinic staff who came to be seen as having expertise in the care of most chronic wounds. This study documents a successful BU outreach and decentralized care program reaching early BU cases not previously treated by a proactive centralized BU program. The pilot program further demonstrates the added value of integrated wound management for NTD control.

Sedimentology of the lower Karoo Supergroup fluvial strata in the Tuli Basin, South Africa

NASA Astrophysics Data System (ADS)

Bordy, Emese M.; Catuneanu, Octavian

2002-11-01

The Karoo Supergroup in the Tuli Basin (South Africa) consists of a sedimentary sequence (˜450-500 m) composed of four stratigraphic units, namely the informal Basal, Middle and Upper Units, and the formal Clarens Formation. The units were deposited in continental settings from approximately Late Carboniferous to Middle Jurassic. This paper focuses on the ˜60-m-thick Basal Unit, which was examined in terms of sedimentary facies and palaeo-environments based on evidence provided by primary sedimentary structures, palaeo-flow measurements, palaeontological findings, borehole data (59 core descriptions) and stratigraphic relations. Three main facies associations have been identified: (i) gravelstone (breccias and conglomerate-breccias), (ii) sandstone and (iii) fine-grained sedimentary rocks. The coarser facies are interpreted as colluvial fan deposits, possibly associated with glaciogenic diamictites. The sandstone facies association is mainly attributed to channel fills of low sinuosity, braided fluvial systems. The coal-bearing finer-grained facies are interpreted as overbank and thaw-lake deposits, and represent the lower energy correlatives of the sandy channel fills. Sediment aggradation in this fluvio-lacustrine system took place under cold climatic conditions, with floating lake ice likely associated with lacustrine environments. Palaeo-current indicators suggest that the highly weathered, quartz-vein-rich metamorphic rock source of the Basal Unit was situated east-northeast of the study area. The accumulation of the Basal Unit took place within the back-bulge depozone of the Karoo foreland system. In addition to flexural subsidence, the amount of accommodation in this tectonic setting was also possibly modified by extensional tectonism in the later stages of the basin development. Based on sedimentological and biostratigraphic evidence, the coal-bearing fine-grained facies association displays strong similarities with the Vryheid Formation of the main Karoo Basin to the south. The lowermost non-fossiliferous breccias have been correlated before with the Dwyka Group in the main Karoo, and hence the Basal Unit may be regarded as the distal equivalent of the Dwyka and Ecca groups to the south.

Longitudinal Associations Among Posttraumatic Stress Disorder, Disordered Eating, and Weight Gain in Military Men and Women

DTIC Science & Technology

2016-06-09

ksmitche@bu.edu). Initially submitted July 14, 2015; accepted for publication October 15, 2015. Obesity is a major health problem in the United States...and a growing concern among members of the military. Posttraumatic stress disorder (PTSD) has been associated with overweight and obesity and may...further investigation of eating disorders in military service members. binge eating; eating disorders; military; obesity Abbreviations: PTSD

Simulating county-level crop yields in the Conterminous United States using the Community Land Model: The effects of optimizing irrigation and fertilization

DOE PAGES

Leng, Guoyong; Zhang, Xuesong; Huang, Maoyi; ...

2016-11-12

Representing agricultural systems explicitly in Earth system models is important for understanding the water-energy-food nexus under climate change. In this study, we applied Version 4.5 of the Community Land Model (CLM) at a 0.125 degree resolution to provide the first county-scale validation of the model in simulating crop yields over the Conterminous United States (CONUS). We focused on corn and soybean that are both important grain crops and biofuel feedstocks (corn for bioethanol; soybean for biodiesel). We find that the default model substantially under- or over-estimate yields of corn and soybean as compared to the US Department of Agriculture (USDA)more » census data, with corresponding county-level root-mean square error (RMSE) of 45.3 Bu/acre and 12.9 Bu/acre, or 42% and 38% of the US mean yields for these crops, respectively. Based on the numerical experiments, the lack of proper representation of agricultural management practices, such as irrigation and fertilization, was identified as a major cause for the model's poor performance. After implementing an irrigation management scheme calibrated against county-level US Geological Survey (USGS) census data, the county-level RMSE for corn yields reduced to 42.6 Bu/acre. We then incorporated an optimized fertilizer scheme in rate and timing, which is achieved by the constraining annual total fertilizer amount against the USDA data, considering the dynamics between fertilizer demand and supply and adopting a calibrated fertilizer scheduling map. The proposed approach is shown to be effective in increasing the fertilizer use efficiency for corn yields, with county-level RMSE reduced to 23.8 Bu/acre (or 22% of the US mean yield). In regions with similar annual fertilizer applied as in the default, the improvements in corn yield simulations are mainly attributed to application of longer fertilization periods and consideration of the dynamics between fertilizer demand and supply. For soybean which is capable of fixing nitrogen to meet nitrogen demand, the reduced positive bias to 6.9 Bu/acre (or 21% of the country mean) was mainly attributed to consideration of the dynamic interactions between fertilizer demand and supply. Although large bias remains in terms of the spatial pattern (i.e. high county-level RMSE), mainly due to limited performance over the Western US, our results show that optimizing irrigation and fertilization can lead to promising improvement in crop and soybean yield simulations in terms of the mean and variability especially over the Mid-west corn belt, and subsequent evapotranspiration (ET) estimates. Finally, this study demonstrates the CLM4.5 capability for predicting crop yields and their interactions with climate, and highlights the value of continued model improvements and development to understand biogeophysical and biogeochemical impacts of land use and land cover change using an Earth system modeling framework.« less

Simulating county-level crop yields in the Conterminous United States using the Community Land Model: The effects of optimizing irrigation and fertilization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leng, Guoyong; Zhang, Xuesong; Huang, Maoyi

Representing agricultural systems explicitly in Earth system models is important for understanding the water-energy-food nexus under climate change. In this study, we applied Version 4.5 of the Community Land Model (CLM) at a 0.125 degree resolution to provide the first county-scale validation of the model in simulating crop yields over the Conterminous United States (CONUS). We focused on corn and soybean that are both important grain crops and biofuel feedstocks (corn for bioethanol; soybean for biodiesel). We find that the default model substantially under- or over-estimate yields of corn and soybean as compared to the US Department of Agriculture (USDA)more » census data, with corresponding county-level root-mean square error (RMSE) of 45.3 Bu/acre and 12.9 Bu/acre, or 42% and 38% of the US mean yields for these crops, respectively. Based on the numerical experiments, the lack of proper representation of agricultural management practices, such as irrigation and fertilization, was identified as a major cause for the model's poor performance. After implementing an irrigation management scheme calibrated against county-level US Geological Survey (USGS) census data, the county-level RMSE for corn yields reduced to 42.6 Bu/acre. We then incorporated an optimized fertilizer scheme in rate and timing, which is achieved by the constraining annual total fertilizer amount against the USDA data, considering the dynamics between fertilizer demand and supply and adopting a calibrated fertilizer scheduling map. The proposed approach is shown to be effective in increasing the fertilizer use efficiency for corn yields, with county-level RMSE reduced to 23.8 Bu/acre (or 22% of the US mean yield). In regions with similar annual fertilizer applied as in the default, the improvements in corn yield simulations are mainly attributed to application of longer fertilization periods and consideration of the dynamics between fertilizer demand and supply. For soybean which is capable of fixing nitrogen to meet nitrogen demand, the reduced positive bias to 6.9 Bu/acre (or 21% of the country mean) was mainly attributed to consideration of the dynamic interactions between fertilizer demand and supply. Although large bias remains in terms of the spatial pattern (i.e. high county-level RMSE), mainly due to limited performance over the Western US, our results show that optimizing irrigation and fertilization can lead to promising improvement in crop and soybean yield simulations in terms of the mean and variability especially over the Mid-west corn belt, and subsequent evapotranspiration (ET) estimates. Finally, this study demonstrates the CLM4.5 capability for predicting crop yields and their interactions with climate, and highlights the value of continued model improvements and development to understand biogeophysical and biogeochemical impacts of land use and land cover change using an Earth system modeling framework.« less

Radioprotection of the Brain White Matter by Mn(III) N-Butoxyethylpyridylporphyrin-Based Superoxide Dismutase Mimic MnTnBuOE-2-PyP5+

PubMed Central

Weitzel, Douglas H.; Tovmasyan, Artak; Ashcraft, Kathleen A.; Rajic, Zrinka; Weitner, Tin; Liu, Chunlei; Li, Wei; Buckley, Anne F.; Prasad, Mark R.; Young, Kenneth H.; Rodriguiz, Ramona M.; Wetsel, William C.; Peters, Katherine B.; Spasojevic, Ivan; Herndon, James E.; Batinic-Haberle, Ines; Dewhirst, Mark W.

2015-01-01

Cranial irradiation is a standard therapy for primary and metastatic brain tumors. A major drawback of radiotherapy (RT), however, is long-term cognitive loss that affects quality of life. Radiation-induced oxidative stress in normal brain tissue is thought to contribute to cognitive decline. We evaluated the effectiveness of a novel mimic of superoxide dismutase enzyme (SOD), MnTnBuOE-2-PyP5+ (Mn(III) meso-tetrakis(N-n-butoxyethylpyridinium-2-yl)porphyrin), to provide long-term neuroprotection following 8 Gy of whole brain irradiation. Long-term RT damage can only be assessed by brain imaging and neurocognitive studies. C57BL/6J mice were treated with MnTnBuOE-2-PyP5+ before and after RT and evaluated three months later. At this time point, drug concentration in the brain was 25 nmol/L. Mice treated with MnTnBuOE-2-PyP5+/RT exhibited MRI evidence for myelin preservation in the corpus callosum compared with saline/RT treatment. Corpus callosum histology demonstrated a significant loss of axons in the saline/RT group that was rescued in the MnTnBuOE-2-PyP5+/RT group. In addition, the saline/RT groups exhibited deficits in motor proficiency as assessed by the rotorod test and running wheel tests. These deficits were ameliorated in groups treated with MnTnBuOE-2-PyP5+/RT. Our data demonstrate that MnTnBuOE-2-PyP5+ is neuroprotective for oxidative stress damage caused by radiation exposure. In addition, glioblastoma cells were not protected by MnTnBuOE-2-PyP5+ combination with radiation in vitro. Likewise, the combination of MnTnBuOE-2-PyP5+ with radiation inhibited tumor growth more than RT alone in flank tumors. In summary, MnTnBuOE-2-PyP5+ has dual activity as a neuroprotector and a tumor radiosensitizer. Thus, it is an attractive candidate for adjuvant therapy with RT in future studies with patients with brain cancer. PMID:25319393

Novel types of tetra-, hexa-, octa-, and dodecanuclear silver clusters containing (2,7-Di-tert-butylfluoren-9-ylidene)methanedithiolate.

PubMed

Vicente, José; González-Herrero, Pablo; García-Sánchez, Yolanda; Jones, Peter G

2009-03-02

The reaction of AgClO(4) with piperidinium 2,7-di-tert-butyl-9H-fluorene-9-carbodithioate (pipH)[S(2)C(t-Bu-Hfy)] (1) (t-Bu-Hfy = 2,7-di-tert-butylfluoren-9-yl) afforded [Ag(n){S(2)C(t-Bu-Hfy)}(n)] (2), which reacted with phosphines to give [Ag{S(2)C(t-Bu-Hfy)}L(2)] [L = PPh(3) (3a); L(2) = bis(diphenylphosphino)ethane (dppe, 3b), 1,1'-bis(diphenylphosphino)ferrocene (dppf, 3c). By reacting complex 2 with AgClO(4) and piperidine in a 1:1:1 molar ratio, the dodecanuclear cluster [Ag(12){S(2)C(t-Bu-fy)}(6)] (4) (t-Bu-fy = 2,7-di-tert-butylfluoren-9-ylidene) was obtained. Compound 4 can also be directly prepared from the reaction of 1 with AgClO(4) and piperidine in a 1:2:1 molar ratio. The reactions of 1 with AgClO(4), phosphines, and piperidine afforded the compounds [Ag(6){S(2)C(t-Bu-fy)}(3)L(5)] [1:2:2:1 molar ratio; L = PPh(3) (5a), P(p-To)(3) (5b)], [Ag(4){S(2)C(t-Bu-fy)}(2)(dppf)(2)] (6) (1:2:1:1 molar ratio), [Ag(n){S(2)C(t-Bu-fy)}(n/2){P(i-Pr)(3)}(n)] (7) (1:2:2:1 molar ratio), or [Ag(8){S(2)C(t-Bu-fy)}(4){P(i-Pr)(3)}(4)] (8) (1:2:1:1 molar ratio). Complexes 5a,b, 6, 7, and 8 can be also obtained by reacting 4 with the corresponding phosphine in the appropriate molar ratio. The crystal structures of 4, 5b, and 8 have been determined by X-ray diffraction studies. The nuclearity of complex 6 was established from its (31)P{(1)H} NMR data, which reveal a very fast dynamic process leading to an average coupling of each of the P atoms of the dppf ligands with four Ag atoms.

Lactolisterin BU, a Novel Class II Broad-Spectrum Bacteriocin from Lactococcus lactis subsp. lactis bv. diacetylactis BGBU1-4.

PubMed

Lozo, Jelena; Mirkovic, Nemanja; O'Connor, Paula M; Malesevic, Milka; Miljkovic, Marija; Polovic, Natalija; Jovcic, Branko; Cotter, Paul D; Kojic, Milan

2017-11-01

Lactococcus lactis subsp. lactis bv. diacetylactis BGBU1-4 produces a novel bacteriocin, lactolisterin BU, with strong antimicrobial activity against many species of Gram-positive bacteria, including important food spoilage and foodborne pathogens, such as Listeria monocytogenes , Staphylococcus aureus , Bacillus spp., and streptococci. Lactolisterin BU was extracted from the cell surface of BGBU1-4 by 2-propanol and purified to homogeneity by C 18 solid-phase extraction and reversed-phase high-performance liquid chromatography. The molecular mass of the purified lactolisterin BU was 5,160.94 Da, and an internal fragment, AVSWAWQH, as determined by N-terminal sequencing, showed low-level similarity to existing antimicrobial peptides. Curing and transformation experiments revealed the presence of a corresponding bacteriocin operon on the smallest plasmid, pBU6 (6.2 kb), of strain BGBU1-4. Analysis of the bacteriocin operon revealed a leaderless bacteriocin of 43 amino acids that exhibited similarity to bacteriocin BHT-B (63%) from Streptococcus ratti , a bacteriocin with analogy to aureocin A. IMPORTANCE Lactolisterin BU, a broad-spectrum leaderless bacteriocin produced by L. lactis subsp. lactis bv. diacetylactis BGBU1-4, expresses strong antimicrobial activity against food spoilage and foodborne pathogens, such as Listeria monocytogenes , Staphylococcus aureus , Bacillus spp., and streptococci. Lactolisterin BU showed the highest similarity to aureocin-like bacteriocins produced by different bacteria. The operon for synthesis is located on the smallest plasmid, pBU6 (6.2 kb), of strain BGBU1-4, indicating possible horizontal transfer among producers. Copyright © 2017 American Society for Microbiology.

Replacement of serum with ocular fluid for cryopreservation of immature testes.

PubMed

Pothana, Lavanya; Devi, Lalitha; Venna, Naresh Kumar; Pentakota, Niharika; Varma, Vivek Phani; Jose, Jedy; Goel, Sandeep

2016-12-01

Cryopreservation of immature testis is a feasible approach for germplasm preservation of male animals. Combinations of dimethyl sulfoxide (DMSO) and foetal bovine serum (FBS) are used for testis cryopreservation. However, an alternative to FBS is needed, because FBS is expensive. Buffalo ocular fluid (BuOF), a slaughter house by-product, could be an economical option. The objective of the present study was to assess whether BuOF can replace FBS for cryopreservation of immature mouse (Mus musculus), rat (Rattus norvegicus), and buffalo (Bubalus bubalis) testes. Results showed that rodent and buffalo testes frozen in DMSO (10% for rodents and 20% for buffalo) with 20% FBS or BuOF had similar numbers of viable and DNA-damaged cells (P > 0.05). The expression of cell proliferation- (PCNA) and apoptosis-specific proteins (Annexin V and BAX/BCL2 ratio) were also comparable in mouse and buffalo testes frozen in DMSO with FBS or BuOF (P > 0.05). Interestingly, rat testis frozen in DMSO with BuOF had lower expression of Annexin V protein than testis frozen in DMSO with FBS (P < 0.05). The percentage of meiotic germ cells (pachytene-stage spermatocytes) in xenografts from testis frozen either in DMSO with BuOF or FBS did not significantly differ in rats or buffalo (P > 0.05). These findings provide evidence that BuOF has potential to replace FBS for cryopreservation of immature rodent and buffalo testis. Further investigation is needed to explore whether BuOF can replace FBS for testis cryopreservation of other species. Copyright © 2016 Elsevier Inc. All rights reserved.

Lactolisterin BU, a Novel Class II Broad-Spectrum Bacteriocin from Lactococcus lactis subsp. lactis bv. diacetylactis BGBU1-4

PubMed Central

Lozo, Jelena; Mirkovic, Nemanja; O'Connor, Paula M.; Malesevic, Milka; Miljkovic, Marija; Polovic, Natalija; Cotter, Paul D.

2017-01-01

ABSTRACT Lactococcus lactis subsp. lactis bv. diacetylactis BGBU1-4 produces a novel bacteriocin, lactolisterin BU, with strong antimicrobial activity against many species of Gram-positive bacteria, including important food spoilage and foodborne pathogens, such as Listeria monocytogenes, Staphylococcus aureus, Bacillus spp., and streptococci. Lactolisterin BU was extracted from the cell surface of BGBU1-4 by 2-propanol and purified to homogeneity by C18 solid-phase extraction and reversed-phase high-performance liquid chromatography. The molecular mass of the purified lactolisterin BU was 5,160.94 Da, and an internal fragment, AVSWAWQH, as determined by N-terminal sequencing, showed low-level similarity to existing antimicrobial peptides. Curing and transformation experiments revealed the presence of a corresponding bacteriocin operon on the smallest plasmid, pBU6 (6.2 kb), of strain BGBU1-4. Analysis of the bacteriocin operon revealed a leaderless bacteriocin of 43 amino acids that exhibited similarity to bacteriocin BHT-B (63%) from Streptococcus ratti, a bacteriocin with analogy to aureocin A. IMPORTANCE Lactolisterin BU, a broad-spectrum leaderless bacteriocin produced by L. lactis subsp. lactis bv. diacetylactis BGBU1-4, expresses strong antimicrobial activity against food spoilage and foodborne pathogens, such as Listeria monocytogenes, Staphylococcus aureus, Bacillus spp., and streptococci. Lactolisterin BU showed the highest similarity to aureocin-like bacteriocins produced by different bacteria. The operon for synthesis is located on the smallest plasmid, pBU6 (6.2 kb), of strain BGBU1-4, indicating possible horizontal transfer among producers. PMID:28842543

Cholinesterase inhibitors modify the activity of intrinsic cardiac neurons.

PubMed

Darvesh, Sultan; Arora, Rakesh C; Martin, Earl; Magee, David; Hopkins, David A; Armour, J Andrew

2004-08-01

Cholinesterase inhibitors used to treat the symptoms of Alzheimer's disease (AD) inhibit both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), albeit to different degrees. Because central and peripheral neurons, including intrinsic cardiac neurons located on the surface of the mammalian heart, express both BuChE and AChE, we studied spontaneously active intrinsic cardiac neurons in the pig as a model to assess the effects of inhibition of AChE compared to BuChE. Neuroanatomical experiments showed that some porcine intrinsic cardiac neurons expressed AChE and/or BuChE. Enzyme kinetic experiments with cholinesterase inhibitors, namely, donepezil, galantamine, (+/-) huperzine A, metrifonate, rivastigmine, and tetrahydroaminoacridine, demonstrated that these compounds differentially inhibited porcine AChE and BuChE. Donepezil and (+/-) huperzine A were better reversible inhibitors of AChE, and galantamine equally inhibited both the enzymes. Tetrahydroaminoacridine was a better reversible inhibitor of BuChE. Rivastigmine caused more rapid inactivation of BuChE as compared to AChE. Neurophysiological studies showed that acetylcholine and butyrylcholine increase or decrease the spontaneous activity of the intrinsic cardiac neurons. Donepezil, galantamine, (+/-) huperzine A, and tetrahydroaminoacridine changed spontaneous neuronal activity by about 30-35 impulses per minute, while rivastigmine changed it by approximately 100 impulses per minute. It is concluded that (i) inhibition of AChE and BuChE directly affects the porcine intrinsic cardiac nervous system, (ii) the intrinsic cardiac nervous system represents a suitable model for examining the effects of cholinesterase inhibitors on mammalian neurons in vivo, and (iii) the activity of intrinsic cardiac neurons may be affected by pharmacological agents that inhibit cholinesterases.

BuGZ is required for Bub3 stability, Bub1 kinetochore function, and chromosome alignment

PubMed Central

Toledo, Chad M.; Herman, Jacob A.; Olsen, Jonathan B.; Ding, Yu; Corrin, Philip; Girard, Emily J.; Olson, James M.; Emili, Andrew; DeLuca, Jennifer G.; Paddison, Patrick J.

2014-01-01

Summary During mitosis, the spindle assembly checkpoint (SAC) monitors the attachment of kinetochores (KTs) to the plus ends of spindle microtubules (MTs) and prevents anaphase onset until chromosomes are aligned and KTs are under proper tension. Here, we identify a SAC component, BuGZ/ZNF207, from an RNAi viability screen in human Glioblastoma multiforme (GBM) brain tumor stem cells. BuGZ binds to and stabilizes Bub3 during interphase and mitosis through a highly conserved GLE2p-binding sequence (GLEBS) domain. Inhibition of BuGZ results in loss of both Bub3 and its binding partner Bub1 from KTs, reduction of Bub1-dependent phosphorylation of centromeric histone H2A, attenuation of KT-based Aurora kinase B activity, and lethal chromosome congression defects in cancer cells. Phylogenetic analysis indicates that BuGZ orthologs are highly conserved among eukaryotes, but are conspicuously absent from budding and fission yeasts. These findings suggest BuGZ has evolved to facilitate Bub3 activity and chromosome congression in higher eukaryotes. PMID:24462187

Homoleptic Ce(III) and Ce(IV) Nitroxide Complexes: Significant Stabilization of the 4+ Oxidation State

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bogart, Justin A.; Lewis, Andrew J.; Medling, Scott A.

2014-06-25

Electrochemical experiments performed on the complex Ce-IV[2-((BuNO)-Bu-t)py](4), where [2-((BuNO)-Bu-t)py](-) = N-tert-butyl-N-2-pyridylnitroxide, indicate a 2.51 V stabilization of the 4+ oxidation state of Ce compared to [(Bu4N)-Bu-n](2)[Ce(NO3)(6)] in acetonitrile and a 2.95 V stabilization compared to the standard potential for the ion under aqueous conditions. Density functional theory calculations suggest that this preference for the higher oxidation state is a result of the tetrakis(nitroxide) ligand framework at the Ce cation, which allows for effective electron donation into, and partial covalent overlap with, vacant 4f orbitals with delta symmetry. The results speak to the behavior of CeO2 and related solid solutions inmore » oxygen uptake and transport applications, in particular an inherent local character of bonding that stabilizes the 4+ oxidation state. The results indicate a cerium(IV) complex that has been stabilized to an unprecedented degree through tuning of its ligand-field environment.« less

Aberrant leukocyte telomere length in Birdshot Uveitis.

PubMed

Vazirpanah, Nadia; Verhagen, Fleurieke H; Rothova, Anna; Missotten, Tom O A R; van Velthoven, Mirjam; Den Hollander, Anneke I; Hoyng, Carel B; Radstake, Timothy R D J; Broen, Jasper C A; Kuiper, Jonas J W

2017-01-01

Birdshot Uveitis (BU) is an archetypical chronic inflammatory eye disease, with poor visual prognosis, that provides an excellent model for studying chronic inflammation. BU typically affects patients in the fifth decade of life. This suggests that it may represent an age-related chronic inflammatory disease, which has been linked to increased erosion of telomere length of leukocytes. To study this in detail, we exploited a sensitive standardized quantitative real-time polymerase chain reaction to determine the peripheral blood leukocyte telomere length (LTL) in 91 genotyped Dutch BU patients and 150 unaffected Dutch controls. Although LTL erosion rates were very similar between BU patients and healthy controls, we observed that BU patients displayed longer LTL, with a median of log (LTL) = 4.87 (= 74131 base pair) compared to 4.31 (= 20417 base pair) in unaffected controls (P<0.0001). The cause underpinning the difference in LTL could not be explained by clinical parameters, immune cell-subtype distribution, nor genetic predisposition based upon the computed weighted genetic risk score of genotyped validated variants in TERC, TERT, NAF1, OBFC1 and RTEL1. These findings suggest that BU is accompanied by significantly longer LTL.

The Place of Career Women in the Basals.

ERIC Educational Resources Information Center

Leondis, Mary T.

A study analyzed two basal reading series to determine if they depicted realistically the role of the career woman as she exists in society. A list of female careers in the 1989 editions of Houghton-Mifflin and McGraw Hill reading basals for grades 1 to 6 was compared to the career categories of the "United States Bureau of Census,…

Energies and excited-state dynamics of 1Bu+, 1Bu- and 3Ag- states of carotenoids bound to LH2 antenna complexes from purple photosynthetic bacteria

NASA Astrophysics Data System (ADS)

Christiana, Rebecca; Miki, Takeshi; Kakitani, Yoshinori; Aoyagi, Shiho; Koyama, Yasushi; Limantara, Leenawaty

2009-10-01

Time-resolved pump-probe stimulated-emission and transient-absorption spectra were recorded after excitation with ˜30 fs pulses to the 1Bu+(0) and optically-forbidden diabatic levels of carotenoids, neurosporene, spheroidene and lycopene having n = 9-11 double bonds, bound to LH2 antenna complexes from Rhodobacter sphaeroides G1C, 2.4.1 and Rhodospirillum molischianum. The low-energy shift of stimulated emission from the covalent 1Bu-(0) and 3Ag-(0) levels slightly larger than that from the ionic 1Bu+(0) state suggests the polarization, whereas more efficient triplet generation suggests the twisting of the conjugated chain in Cars bound to the LH2 complexes, when compared to Cars free in solution.

Ground water in the Sirte area, Tripolitania, United Kingdom of Libya

USGS Publications Warehouse

Ogilbee, William

1964-01-01

The present study of the ground-water conditions in the Sirte area was made during December 1961 and March-April 1962 at the request of officials of the Government of Libya. Particular attention was given to the potential of the fresh-water aquifer near Qasr Bu Itadi as a source of water for Sirte. The Sirte area lies on the southern coast of the Mediterranean Sea about 450 kilometers east-southeast of Tripoli, cocapital of Libya. Although the area receives some winter precipitation, the climate is arid. The surface rocks of the area are chiefly Miocene limestone containing marl, clay, and some sandstone, though Quaternary deposits occur along the wadis and mantle the Miocene rocks in the coastal plain. Fresh ground water occurs locally in Recent sand dunes near Zaafran and in Miocene limestone near Qasr Bu Hadi, south of a probable fault. Elsewhere in the Sirte area, ground water occurs generally in Tertiary rocks but contains 3,000 or more parts per million of dissolved solids. To establish the hydraulic characteristics of the fresh-water aquifer in the Qasr Bu Itadi area, two test wells were drilled and a controlled pumping test was made. The coefficient of transmissibility was found to be about 25,000 gallons per day per foot (13.68 cubic meters per hour per meter), and the coefficient of storage, about 0.00055. The pumping test also established the presence of two barrier-type hydraulic boundaries for the aquifer, one about 250 meters westward and another about 535 meters northward from well 9a. The first boundary is probably the small anticline on which stands the fort of Qasr Bu Itadi; the second boundary is probably a northwest trending fault. Using the transmissibility and storage coefficients derived from the pumping test, the writer concludes that (1) the total draft from the fresh-water aquifer should not exceed 13.5 cubic meters per hour and (2) production wells should be at least 3 kilometers south of well 9a.

Synthesis and structures of a pincer-type rhodium(iii) complex: reactivity toward biomolecules.

PubMed

Milutinović, Milan M; Bogojeski, Jovana V; Klisurić, Olivera; Scheurer, Andreas; Elmroth, Sofi K C; Bugarčić, Živadin D

2016-10-04

A novel rhodium(iii) complex [Rh III (H 2 L tBu )Cl 3 ] (1) (H 2 L tBu = 2,6-bis(5-tert-butyl-1H-pyrazol-3-yl)pyridine) containing a pincer type, tridentate nitrogen-donor chelate system was synthesized. Single crystal X-ray structure analysis revealed that 1 crystallizes in the orthorhombic space group Pbcn with a = 20.7982(6), b = 10.8952(4), c = 10.9832(4) Å, V = 2488.80(15) Å 3 , and eight molecules in the unit cell. The rhodium center in the complex [Rh III (H 2 L tBu )Cl 3 ] (1) is coordinated in a slightly distorted octahedral geometry by the tridentate N,N,N-donor and three chloro ligands, adopting a mer arrangement with an essentially planar ligand skeleton. Due to the tridentate coordination of the N,N,N-donor, the central nitrogen atom N1 is located closer to the Rh III center. The reactivity of the synthesized complex toward small biomolecules (l-methionine (l-Met), guanosine-5'-monophosphate (5'-GMP), l-histidine (l-His) and glutathione (GSH)) and to a series of duplex DNAs and RNA was investigated. The order of reactivity of the studied small biomolecules is: 5'-GMP > GSH > l-Met > l-His. Duplex RNA reacts faster with the [Rh III (H 2 L tBu )Cl 3 ] complex than duplex DNA, while shorter duplex DNA (15mer GG) reacts faster compared with 22mer GG duplex DNA. In addition, a higher reactivity is achieved with a DNA duplex with a centrally located GG-sequence than with a 22GTG duplex DNA, in which the GG-sequence is separated by a T base. Furthermore, the interaction of this metal complex 1 with calf thymus DNA (CT-DNA) and bovine serum albumin (BSA) was examined by absorption (UV-Vis) and emission spectral studies (EthBr displacement studies). Overall, the studied complex exhibited good DNA and BSA interaction ability.

Enzymatic hydrolysis and fermentation of corn for fuel alcohol

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mullins, J.T.

1985-01-01

The integration of enzyme saccharification with fermentation reduces the total time required to produce acceptable levels of ethanol. The use of a more concentrated mash (84.8 L total mash/bu corn) results in a 26.6% increase in ethanol productivity and a 21.4% increase in beer ethanol concentration compared to standard corn mash (96.6 L total mash/bu corn). Thus, the energy requirement and cost of distillation can be reduced. The addition of waste cola syrup at 30 g invert sugar/L total mash gave a 19% increase in ethanol concentration in the final beer and required only a small increase in period ofmore » fermentation. Surplus laundry starch can replace 30-50% of the weight of corn normally used in fermentation without influencing ethanol production or the time required for fermentation. Both of these waste materials reduce the unit cost of ethanol and demonstrate the value of such substances in ethanol systems.« less

Synthesis and transformations of alkylphosphate and alkoxysiloxide metal complexes to multicomponent oxide materials

NASA Astrophysics Data System (ADS)

Lugmair, Claus Guenter

This thesis describes the synthesis of mixed element oxide materials utilizing oxygen rich ``single-source precursor'' molecules. The key attributes of these precursor complexes are that they possess the stoichiometry of the targeted oxide material and that they can be converted to carbon free materials by mild thermal treatment. Complexes of Al, Cu, Fe, Hf, Nb, Ta, Ti, and Zr were prepared that contain tris(tert-butoxy)siloxy ligands as precursors to silica based materials. The pyrolytic decomposition of these complexes occur under mild conditions, with onset temperatures to decomposition between 95 and 200sp°C. The resulting metal-silica or metal oxide-silica materials contain very little carbon. The solid state transformation of Zrlbrack OSi(OsptBu)sb3rbracksb4 to ZrOsb2{*}4SiOsb2 produced an open fibrous material with pores which are ca. 20 nm in diameter. The solution phase thermolysis of the various metal siloxide complexes in anhydrous organic solvents led to xerogels consisting of small spherical primary particles (≤ca. 5 nm). These xerogels typically possess very high surface areas. The ZrOsb2{*}4SiOsb2 materials are amorphous as initially formed, and subsequent crystallizations of tetragonal ZrOsb2, monoclinic ZrOsb2, and cristobalite occur at relatively high temperatures. The enhanced stabilization of the amorphous and tetragonal phases of zirconia, relative to those derived from many sol-gel systems, implies that these single-source precursors initially produce highly homogeneous materials and that subsequent crystallizations are to a large degree diffusion-controlled, Careful addition of 1 or 2 equiv of water to THF solutions of Mlbrack OSi(OsptBu)sb3rbracksb4 (M = Zr, Hf) produced the isolable aqua complexes Mlbrack OSi(OsptBu)sb3rbracksb4(Hsb2O) and Mlbrack OSi(OsptBu)sb3rbracksb4(Hsb2O)sb2. It is likely that the hydrolysis of Zrlbrack OSi(OsptBu)sb3rbracksb4(Hsb2O)sb2 also occurs by an associative mechanism via the tris(aqua) intermediate Zrlbrack OSi(Osp{t}Bu)sb3rbracksb4(Hsb2O)sb3. The reaction of ZnEtsb2 with HO(O)P(OsptBu)sb2 in the presence of slight amounts of water produced good yields of the oxo-centered tetranuclear cluster Znsb4(musb4-O)lbrack Osb2P(OsptBu)sb2rbracksb6. When this complex was heated in ethanol at 85sp°C for 30 h, or dissolved in acid containing solutions, it converted to a polymer, \\{Znlbrack Osb2P(OsptBu)sb2rbracksb2\\}sbn, which contains zinc atoms that are linked alternately by one and then three bridging phosphate groups. Diffusion of a toluene solution of Znsb4(musb4-O)lbrack Osb2P(OsptBu)sb2rbracksb6 into a dichloromethane solution of 1,6-hexanediamine produced a layered coordination network with the formula \\{Znlbrack Osb2P(OsptBu)sb2rbracksb2lbrack Hsb2N(CHsb2)sb6NHsb2rbrack\\}sbn. The reaction between Znsb4(musb4-O)lbrack Osb2P(OsptBu)sb2rbracksb6 and either 4 or 8 equiv of n-alkylamines in toluene or isopropanol at elevated temperatures (180-220sp°C) led to the formation of lamellar zincophosphate materials. These mesophases consist of zinc phosphate layers that are separated by layers of n-alkylamines which adopt either an interdigitated or a double layer arrangement. Reactions of 1 equiv of HO(O)P(OsptBu)sb2 with Ti(OR)sb4 (R = Et, spiPr) gave the new molecular titanium phosphates lbrack Ti(OR)sb3Osb2P(OsptBu)sb2rbracksbn (R = Et, spiPr). Addition of 2 equiv of KOEt to an ethanol solution of lbrack Ti(OEt)sb3Osb2P(OsptBu)sb2rbracksbn led to the formation of lbrack Tisb2K(OEt)sb8Osb2P(OsptBu)sb2rbracksb2 and 1 equiv of KOsb2P(OsptBu)sb2. Addition of 2 equiv of KOspiPr to an isopropanol solution of lbrack Ti(OspiPr)sb3Osb2P(OsptBu)sb2rbracksb2 led to the formation of KOsb2P(OsptBu)sb2 and Ti(OspiPr)sb4 in high yield. (Abstract shortened by UMI.)

MnTnBuOE-2-PyP protects normal colorectal fibroblasts from radiation damage and simultaneously enhances radio/chemotherapeutic killing of colorectal cancer cells

PubMed Central

Kosmacek, Elizabeth A.; Chatterjee, Arpita; Tong, Qiang; Lin, Chi; Oberley, Rebecca E.

2016-01-01

Manganese porphyrins have been shown to be potent radioprotectors in a variety of cancer models. However, the mechanism as to how these porphyrins protect normal tissues from radiation damage still remains largely unknown. In the current study, we determine the effects of the manganese porphyrin, MnTnBuOE-2-PyP, on primary colorectal fibroblasts exposed to irradiation. We found that 2 Gy of radiation enhances the fibroblasts' ability to contract a collagen matrix, increases cell size and promotes cellular senesence. Treating fibroblasts with MnTnBuOE-2-PyP significantly inhibited radiation-induced collagen contraction, preserved cell morphology and also inhibited cellular senescence. We further showed that MnTnBuOE-2-PyP enhanced the overall viability of the fibroblasts following exposure to radiation but did not protect colorectal cancer cell viability. Specifically, MnTnBuOE-2-PyP in combination with irradiation, caused a significant decrease in tumor clonogenicity. Since locally advanced rectal cancers are treated with chemoradiation therapy followed by surgery and non-metastatic anal cancers are treated with chemoradiation therapy, we also investigated the effects of MnTnBuOE-2-PyP in combination with radiation, 5-fluorouracil with and without Mitomycin C. We found that MnTnBuOE-2-PyP in combination with Mitomycin C or 5-fluorouracil further enhances those compounds' ability to suppress tumor cell growth. When MnTnBuOE-2-PyP was combined with the two chemotherapeutics and radiation, we observed the greatest reduction in tumor cell growth. Therefore, these studies indicate that MnTnBuOE-2-PyP could be used as a potent radioprotector for normal tissue, while at the same time enhancing radiation and chemotherapy treatment for rectal and anal cancers. PMID:27119354

TXNIP mediates the differential responses of A549 cells to sodium butyrate and sodium 4-phenylbutyrate treatment.

PubMed

Jin, Xuefang; Wu, Nana; Dai, Juji; Li, Qiuxia; Xiao, XiaoQiang

2017-02-01

Sodium butyrate (NaBu) and sodium 4-phenylbutyrate (4PBA) have promising futures in cancer treatment; however, their underlying molecular mechanisms are not clearly understood. Here, we show A549 cell death induced by NaBu and 4PBA are not the same. NaBu treatment induces a significantly higher level of A549 cell death than 4PBA. A gene expression microarray identified more than 5000 transcripts that were altered (>1.5-fold) in NaBu-treated A549 cells, but fewer than 2000 transcripts that were altered in 4PBA. Moreover, more than 100 cell cycle-associated genes were greatly repressed by NaBu, but slightly repressed by 4PBA; few genes were significantly upregulated only in 4PBA-treated cells. Gene expression was further validated by other experiments. Additionally, A549 cells that were treated with these showed changes in glucose consumption, caspase 3/7 activation and histone modifications, as well as enhanced mitochondrial superoxide production. TXNIP was strongly induced by NaBu (30- to 40-fold mRNA) but was only slightly induced by 4PBA (two to fivefold) in A549 cells. TXNIP knockdown by shRNA in A549 cells significantly attenuated caspase 3/7 activation and restored cell viability, while TXNIP overexpression significantly increased caspase 3/7 activation and cell death only in NaBu-treated cells. Moreover, TXNIP also regulated NaBu- but not 4PBA-induced H4K5 acetylation and H3K4 trimethylation, possibly by increasing WDR5 expression. Finally, we demonstrated that 4PBA induced a mitochondrial superoxide-associated cell death, while NaBu did so mainly through a TXNIP-mediated pathway. The above data might benefit the future clinic application. © 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Risk factors for buruli ulcer in Ghana-a case control study in the Suhum-Kraboa-Coaltar and Akuapem South Districts of the eastern region.

PubMed

Kenu, Ernest; Nyarko, Kofi Mensah; Seefeld, Linda; Ganu, Vincent; Käser, Michael; Lartey, Margaret; Calys-Tagoe, Benedict Nii Laryea; Koram, Kwodwo; Adanu, Richard; Razum, Oliver; Afari, Edwin; Binka, Fred N

2014-01-01

Buruli ulcer (BU) is a skin disease caused by Mycobacterium ulcerans. Its exact mode of transmission is not known. Previous studies have identified demographic, socio-economic, health and hygiene as well as environment related risk factors. We investigated whether the same factors pertain in Suhum-Kraboa-Coaltar (SKC) and Akuapem South (AS) Districts in Ghana which previously were not endemic for BU. We conducted a case control study. A case of BU was defined as any person aged 2 years or more who resided in study area (SKC or AS District) diagnosed according to the WHO clinical case definition for BU and matched with age- (+/-5 years), gender-, and community controls. A structured questionnaire on host, demographic, environmental, and behavioural factors was administered to participants. A total of 113 cases and 113 community controls were interviewed. Multivariate conditional logistic regression analysis identified presence of wetland in the neighborhood (OR=3.9, 95% CI=1.9-8.2), insect bites in water/mud (OR=5.7, 95% CI=2.5-13.1), use of adhesive when injured (OR=2.7, 95% CI=1.1-6.8), and washing in the Densu river (OR=2.3, 95% CI=1.1-4.96) as risk factors associated with BU. Rubbing an injured area with alcohol (OR=0.21, 95% CI=0.008-0.57) and wearing long sleeves for farming (OR=0.29, 95% CI=0.14-0.62) showed protection against BU. This study identified the presence of wetland, insect bites in water, use of adhesive when injured, and washing in the river as risk factors for BU; and covering limbs during farming as well as use of alcohol after insect bites as protective factors against BU in Ghana. Until paths of transmission are unraveled, control strategies in BU endemic areas should focus on these known risk factors.

MnTnBuOE-2-PyP protects normal colorectal fibroblasts from radiation damage and simultaneously enhances radio/chemotherapeutic killing of colorectal cancer cells.

PubMed

Kosmacek, Elizabeth A; Chatterjee, Arpita; Tong, Qiang; Lin, Chi; Oberley-Deegan, Rebecca E

2016-06-07

Manganese porphyrins have been shown to be potent radioprotectors in a variety of cancer models. However, the mechanism as to how these porphyrins protect normal tissues from radiation damage still remains largely unknown. In the current study, we determine the effects of the manganese porphyrin, MnTnBuOE-2-PyP, on primary colorectal fibroblasts exposed to irradiation. We found that 2 Gy of radiation enhances the fibroblasts' ability to contract a collagen matrix, increases cell size and promotes cellular senesence. Treating fibroblasts with MnTnBuOE-2-PyP significantly inhibited radiation-induced collagen contraction, preserved cell morphology and also inhibited cellular senescence. We further showed that MnTnBuOE-2-PyP enhanced the overall viability of the fibroblasts following exposure to radiation but did not protect colorectal cancer cell viability. Specifically, MnTnBuOE-2-PyP in combination with irradiation, caused a significant decrease in tumor clonogenicity. Since locally advanced rectal cancers are treated with chemoradiation therapy followed by surgery and non-metastatic anal cancers are treated with chemoradiation therapy, we also investigated the effects of MnTnBuOE-2-PyP in combination with radiation, 5-fluorouracil with and without Mitomycin C. We found that MnTnBuOE-2-PyP in combination with Mitomycin C or 5-fluorouracil further enhances those compounds' ability to suppress tumor cell growth. When MnTnBuOE-2-PyP was combined with the two chemotherapeutics and radiation, we observed the greatest reduction in tumor cell growth. Therefore, these studies indicate that MnTnBuOE-2-PyP could be used as a potent radioprotector for normal tissue, while at the same time enhancing radiation and chemotherapy treatment for rectal and anal cancers.

A Community Based Study on the Mode of Transmission, Prevention and Treatment of Buruli Ulcers in Southwest Cameroon: Knowledge, Attitude and Practices.

PubMed

Akoachere, Jane-Francis K T; Nsai, Frankline S; Ndip, Roland N

2016-01-01

Buruli ulcer (BU) is a neglected tropical disease affecting the skin, tissues and in some cases the bones, caused by the environmental pathogen Mycobacterium ulcerans (M. ulcerans). Its mode of transmission is still elusive. Delayed treatment may cause irreversible disabilities with consequent social and economic impacts on the victim. Socio-cultural beliefs, practices and attitudes in endemic communities have been shown to influence timely treatment causing disease management, prevention and control a great challenge. An assessment of these factors in endemic localities is important in designing successful intervention strategies. Considering this, we assessed the knowledge, attitude and practices regarding BU in three endemic localities in the South West region, Cameroon to highlight existing misconceptions that need to be addressed to enhance prompt treatment and facilitate effective prevention and control. A cross-sectional study was executed in three BU endemic health districts. Using qualitative and quantitative approaches we surveyed 320 randomly selected household heads, interviewed BU patients and conducted three focus group discussions (FGDs) to obtain information on awareness, beliefs, treatment, and attitudes towards victims. The influence of socio-demographic factors on these variables was investigated. Respondents (84.4%) had a good knowledge of BU though only 65% considered it a health problem while 49.4% believed it is contagious. Socio-demographic factors significantly (P<0.05) influenced awareness of BU, knowledge and practice on treatment and attitudes towards victims. Although the majority of respondents stated the hospital as the place for appropriate treatment, FGDs and some BU victims preferred witchdoctors/herbalists and prayers, and considered the hospital as the last option. We documented beliefs about the disease which could delay treatment. Though we are reporting a high level of knowledge of BU, there exist fallacies about BU and negative attitudes towards victims in communities studied. Efforts towards disease eradication must first of all target these misconceptions.

Prevalence of antibodies against Bubaline herpesvirus (BuHV-1) among Mediterranean water buffalo (Bubalus bubalis) with implications in buffalo trade.

PubMed

Caruso, C; Prato, R; Ingravalle, F; Vecchio, D; Sciarra, A; Ternavasio, M; Ceccarelli, L; Martucciello, A; Galiero, G; De Carlo, E; Masoero, L

2016-12-01

Both Bovine herpesvirus (BoHV-1) and Bubaline herpesvirus (BuHV-1) have been reported to cross the species barrier. Antibody seroconversion in glycoprotein E (gE) blocking ELISA during BuHV-1 infection has been documented. Recent diagnostic efforts have focused on the development and application of discriminatory tests to distinguish between infections with BoHV-1 and BuHV-1. To evaluate the impact and distribution of these two infections in water buffalo farms in two regions (Piedmont (n = 3) and Campania (n = 10), Italy) where infectious bovine rhinotracheitis control programs have been implemented. Sampling was carried out on 13 buffalo farms comprising 1089 animals using specific gE-indirect ELISA's test able to discriminate among BoHV-1 and BuHV-1 infections. 59.0% of animals reacted positive to ELISA (irrespective of whether BoHV-1 or BuHV-1 antigen was used) and 86.4% of these were reactive to BuHV-1 only, whereas 11.8% showed absorbance values for both antigens and were classified as inconclusive. There was a statistically significant age-related difference in BuHV-1 infection rates but not in overall individual (47% vs. 58%) or herd prevalence (100% vs. 90%) of infection between the two regions. The low percentage of sera reactive to BoHV-1 (1.8%, 12/643) indicates that BuHV-1 may be the main circulating alphaherpesvirus infection in Mediterranean water buffalo in the two study areas. Since Bubalus bubalis is included in Directive 64/432/EEC on animal health problems affecting intra-community trade in bovine animals, diagnostic testing with nonspecific ELISA for BoHV-1 infection in buffalo may yield false-positive reactions. This scenario could lead to economic losses and hamper buffalo trade and movement, particularly for reproduction purposes.

A Community Based Study on the Mode of Transmission, Prevention and Treatment of Buruli Ulcers in Southwest Cameroon: Knowledge, Attitude and Practices

PubMed Central

Akoachere, Jane-Francis K. T.; Nsai, Frankline S.; Ndip, Roland N.

2016-01-01

Background Buruli ulcer (BU) is a neglected tropical disease affecting the skin, tissues and in some cases the bones, caused by the environmental pathogen Mycobacterium ulcerans (M. ulcerans). Its mode of transmission is still elusive. Delayed treatment may cause irreversible disabilities with consequent social and economic impacts on the victim. Socio-cultural beliefs, practices and attitudes in endemic communities have been shown to influence timely treatment causing disease management, prevention and control a great challenge. An assessment of these factors in endemic localities is important in designing successful intervention strategies. Considering this, we assessed the knowledge, attitude and practices regarding BU in three endemic localities in the South West region, Cameroon to highlight existing misconceptions that need to be addressed to enhance prompt treatment and facilitate effective prevention and control. Methods and Findings A cross-sectional study was executed in three BU endemic health districts. Using qualitative and quantitative approaches we surveyed 320 randomly selected household heads, interviewed BU patients and conducted three focus group discussions (FGDs) to obtain information on awareness, beliefs, treatment, and attitudes towards victims. The influence of socio-demographic factors on these variables was investigated. Results Respondents (84.4%) had a good knowledge of BU though only 65% considered it a health problem while 49.4% believed it is contagious. Socio-demographic factors significantly (P<0.05) influenced awareness of BU, knowledge and practice on treatment and attitudes towards victims. Although the majority of respondents stated the hospital as the place for appropriate treatment, FGDs and some BU victims preferred witchdoctors/herbalists and prayers, and considered the hospital as the last option. We documented beliefs about the disease which could delay treatment. Conclusion Though we are reporting a high level of knowledge of BU, there exist fallacies about BU and negative attitudes towards victims in communities studied. Efforts towards disease eradication must first of all target these misconceptions. PMID:27227429

Basal area growth for aspen suckers under simulated browsing on Cedar Mountain, southern Utah, western United States of America

Treesearch

K. Tshireletso; J. C. Malechek; D. L. Bartos

2010-01-01

The objective of the study was to determine the effects of season and intensity of clipping using simulated browsing on suckers' (Populus tremulaides Michx.) basal area growth on Cedar Mountain, Southern Utah, Western United States of America. Three randomly selected stands measuring 70 m x 70 m were clear-felled in mid-July, 2005, and fenced. Simulated browsing...

Denervation does not alter the number of neuronal bungarotoxin binding sites on autonomic neurons in the frog cardiac ganglion.

PubMed

Sargent, P B; Bryan, G K; Streichert, L C; Garrett, E N

1991-11-01

The binding of neuronal bungarotoxin (n-BuTX; also known as bungarotoxin 3.1, kappa-bungarotoxin, and toxin F) was analyzed in normal and denervated parasympathetic cardiac ganglia of the frog Rana pipiens, n-BuTX blocks both EPSPs and ACh potentials at 5-20 nM, as determined by intracellular recording techniques. Scatchard analysis on homogenates indicates that cardiac ganglia have two classes of binding sites for 125I-n-BuTX: a high-affinity site with an apparent dissociation constant (Kd,app) of 1.7 nM and a Bmax (number of binding sites) of 3.8 fmol/ganglion and a low-affinity site with a Kd,app of 12 microM and a Bmax of 14 pmol/ganglion. alpha-Bungarotoxin does not appear to interfere with the binding of 125I-n-BuTX to either site. The high-affinity binding site is likely to be the functional nicotinic ACh receptor (AChR), given the similarity between its affinity for 125I-n-BuTX and the concentration of n-BuTX required to block AChR function. Light microscopic autoradiographic analysis of 125I-n-BuTX binding to the ganglion cell surface reveals that toxin binding is concentrated at synaptic sites, which were identified using a synaptic vesicle-specific antibody. Scatchard analysis of autoradiographic data reveals that 125I-n-BuTX binding to the neuronal surface is saturable and has a Kd,app similar to that of the high-affinity binding site characterized in homogenates. Surface binding of 125I-n-BuTX is blocked by nicotine, carbachol, and d-tubocurarine (IC50 less than 20 microM), but not by atropine (IC50 greater than 10 mM). Denervation of the heart increases the ACh sensitivity of cardiac ganglion cells but has no effect upon the number of high-affinity binding sites for 125I-n-BuTX in tissue homogenates. Moreover, autoradiographic analysis indicates that denervation does not alter the number of 125I-n-BuTX binding sites on the ganglion cell surface. n-BuTX is as effective in reducing ganglion cell responses to ACh in denervated ganglia as it is in normally innervated ganglia. These results suggest that denervation alters neither the total number of nicotinic AChRs in the cardiac ganglion nor the number found on the surface of ganglion cells. These autonomic neurons thus respond differently to denervation than do skeletal myofibers. The increase in ACh sensitivity displayed by cardiac ganglion cells upon denervation cannot be explained by changes in AChR number.

14 CFR Appendix E to Part 121 - Flight Training Requirements

Code of Federal Regulations, 2011 CFR

2011-01-01

... Authority or by the person conducting the training B AT BU (d) Pretakeoff checks that include power-plant... conditions, wind direction and velocity, brake heat energy, and any other pertinent factors that may... sequence from an ILS instrument approach B AT AT BU (d) Cross wind landing B AT BU (e) Maneuvering to a...

14 CFR Appendix E to Part 121 - Flight Training Requirements

Code of Federal Regulations, 2010 CFR

2010-01-01

... Authority or by the person conducting the training B AT BU (d) Pretakeoff checks that include power-plant... conditions, wind direction and velocity, brake heat energy, and any other pertinent factors that may... sequence from an ILS instrument approach B AT AT BU (d) Cross wind landing B AT BU (e) Maneuvering to a...

Challenges and unmet needs in basal insulin therapy: lessons from the Asian experience

PubMed Central

Chan, Wing Bun; Chen, Jung Fu; Goh, Su-Yen; Vu, Thi Thanh Huyen; Isip-Tan, Iris Thiele; Mudjanarko, Sony Wibisono; Bajpai, Shailendra; Mabunay, Maria Aileen; Bunnag, Pongamorn

2017-01-01

Basal insulin therapy can improve glycemic control in people with type 2 diabetes. However, timely initiation, optimal titration, and proper adherence to prescribed basal insulin regimens are necessary to achieve optimal glycemic control. Even so, glycemic control may remain suboptimal in a significant proportion of patients. Unique circumstances in Asia (eg, limited resources, management of diabetes primarily in nonspecialist settings, and patient populations that are predominantly less educated) coupled with the limitations of current basal insulin options (eg, risk of hypoglycemia and dosing time inflexibility) amplify the challenge of optimal basal insulin therapy in Asia. Significant progress has been made with long-acting insulin analogs (insulin glargine 100 units/mL and insulin detemir), which provide longer coverage and less risk of hypoglycemia over intermediate-acting insulin (Neutral Protamine Hagedorn insulin). Furthermore, recent clinical evidence suggests that newer long-acting insulin analogs, new insulin glargine 300 units/mL and insulin degludec, may address some of the unmet needs of current basal insulin options in terms of risk of hypoglycemia and dosing time inflexibility. Nevertheless, more can be done to overcome barriers to basal insulin therapy in Asia, through educating both patients and physicians, developing better patient support models, and improving accessibility to long-acting insulin analogs. In this study, we highlight the unique challenges associated with basal insulin therapy in Asia and, where possible, propose strategies to address the unmet needs by drawing on clinical experiences and perspectives in Asia. PMID:29276400

Challenges and unmet needs in basal insulin therapy: lessons from the Asian experience.

PubMed

Chan, Wing Bun; Chen, Jung Fu; Goh, Su-Yen; Vu, Thi Thanh Huyen; Isip-Tan, Iris Thiele; Mudjanarko, Sony Wibisono; Bajpai, Shailendra; Mabunay, Maria Aileen; Bunnag, Pongamorn

2017-01-01

Basal insulin therapy can improve glycemic control in people with type 2 diabetes. However, timely initiation, optimal titration, and proper adherence to prescribed basal insulin regimens are necessary to achieve optimal glycemic control. Even so, glycemic control may remain suboptimal in a significant proportion of patients. Unique circumstances in Asia (eg, limited resources, management of diabetes primarily in nonspecialist settings, and patient populations that are predominantly less educated) coupled with the limitations of current basal insulin options (eg, risk of hypoglycemia and dosing time inflexibility) amplify the challenge of optimal basal insulin therapy in Asia. Significant progress has been made with long-acting insulin analogs (insulin glargine 100 units/mL and insulin detemir), which provide longer coverage and less risk of hypoglycemia over intermediate-acting insulin (Neutral Protamine Hagedorn insulin). Furthermore, recent clinical evidence suggests that newer long-acting insulin analogs, new insulin glargine 300 units/mL and insulin degludec, may address some of the unmet needs of current basal insulin options in terms of risk of hypoglycemia and dosing time inflexibility. Nevertheless, more can be done to overcome barriers to basal insulin therapy in Asia, through educating both patients and physicians, developing better patient support models, and improving accessibility to long-acting insulin analogs. In this study, we highlight the unique challenges associated with basal insulin therapy in Asia and, where possible, propose strategies to address the unmet needs by drawing on clinical experiences and perspectives in Asia.

40 CFR Appendix B to Subpart E of... - Federal Guidelines-User Charges for Operation and Maintenance of Publicly Owned Treatment Works

Code of Federal Regulations, 2011 CFR

2011-07-01

.... S = Concentration of SS from a user above a base level. Pc = O&M cost for treatment of a unit of any...(B)=Sc(S)=Pc(P)]Vu (3) Model No. 3. This model is commonly called the “quantity/quality formula”: Cu = Vc Vu=Bc Bu=Sc Su=Pc Pu (h) Other considerations. (1) Quantity discounts to large volume users will...

Buruli ulcer disease prevalence in Benin, West Africa: Associations with land use/cover and the identification of disease clusters

USGS Publications Warehouse

Wagner, T.; Benbow, M.E.; Brenden, T.O.; Qi, J.; Johnson, R.C.

2008-01-01

Background: Buruli ulcer (BU) disease, caused by infection with the environmental mycobacterium M. ulcerans, is an emerging infectious disease in many tropical and sub-tropical countries. Although vectors and modes of transmission remain unknown, it is hypothesized that the transmission of BU disease is associated with human activities in or around aquatic environments, and that characteristics of the landscape (e.g., land use/cover) play a role in mediating BU disease. Several studies performed at relatively small spatial scales (e.g., within a single village or region of a country) support these hypotheses; however, if BU disease is associated with land use/cover characteristics, either through spatial constraints on vector-host dynamics or by mediating human activities, then large-scale (i.e., country-wide) associations should also emerge. The objectives of this study were to (1) investigate associations between BU disease prevalence in villages in Benin, West Africa and surrounding land use/cover patterns and other map-based characteristics, and (2) identify areas with greater and lower than expected prevalence rates (i.e., disease clusters) to assist with the development of prevention and control programs. Results: Our landscape-based models identified low elevation, rural villages surrounded by forest land cover, and located in drainage basins with variable wetness patterns as being associated with higher BU disease prevalence rates. We also identified five spatial disease clusters. Three of the five clusters contained villages with greater than expected prevalence rates and two clusters contained villages with lower than expected prevalence rates. Those villages with greater than expected BU disease prevalence rates spanned a fairly narrow region of south-central Benin. Conclusion: Our analyses suggest that interactions between natural land cover and human alterations to the landscape likely play a role in the dynamics of BU disease. For example, urbanization, potentially by providing access to protected water sources, may reduce the likelihood of becoming infected with BU disease. Villages located at low elevations may have higher BU disease prevalence rates due to their close spatial proximity to high risk environments. In addition, forest land cover and drainage basins with variable wetness patterns may be important for providing suitable growth conditions for M. ulcerans, influencing the distribution and abundance of vectors, or mediating vector-human interactions. The identification of disease clusters in this study provides direction for future research aimed at better understanding these and other environmental and social determinants involved in BU disease outbreaks. ?? 2008 Wagner et al; licensee BioMed Central Ltd.

Buruli ulcer disease prevalence in Benin, West Africa: associations with land use/cover and the identification of disease clusters

PubMed Central

Wagner, Tyler; Benbow, M Eric; Brenden, Travis O; Qi, Jiaguo; Johnson, R Christian

2008-01-01

Background Buruli ulcer (BU) disease, caused by infection with the environmental mycobacterium M. ulcerans, is an emerging infectious disease in many tropical and sub-tropical countries. Although vectors and modes of transmission remain unknown, it is hypothesized that the transmission of BU disease is associated with human activities in or around aquatic environments, and that characteristics of the landscape (e.g., land use/cover) play a role in mediating BU disease. Several studies performed at relatively small spatial scales (e.g., within a single village or region of a country) support these hypotheses; however, if BU disease is associated with land use/cover characteristics, either through spatial constraints on vector-host dynamics or by mediating human activities, then large-scale (i.e., country-wide) associations should also emerge. The objectives of this study were to (1) investigate associations between BU disease prevalence in villages in Benin, West Africa and surrounding land use/cover patterns and other map-based characteristics, and (2) identify areas with greater and lower than expected prevalence rates (i.e., disease clusters) to assist with the development of prevention and control programs. Results Our landscape-based models identified low elevation, rural villages surrounded by forest land cover, and located in drainage basins with variable wetness patterns as being associated with higher BU disease prevalence rates. We also identified five spatial disease clusters. Three of the five clusters contained villages with greater than expected prevalence rates and two clusters contained villages with lower than expected prevalence rates. Those villages with greater than expected BU disease prevalence rates spanned a fairly narrow region of south-central Benin. Conclusion Our analyses suggest that interactions between natural land cover and human alterations to the landscape likely play a role in the dynamics of BU disease. For example, urbanization, potentially by providing access to protected water sources, may reduce the likelihood of becoming infected with BU disease. Villages located at low elevations may have higher BU disease prevalence rates due to their close spatial proximity to high risk environments. In addition, forest land cover and drainage basins with variable wetness patterns may be important for providing suitable growth conditions for M. ulcerans, influencing the distribution and abundance of vectors, or mediating vector-human interactions. The identification of disease clusters in this study provides direction for future research aimed at better understanding these and other environmental and social determinants involved in BU disease outbreaks. PMID:18505567

Performance, emission, and combustion characteristics of twin-cylinder common rail diesel engine fuelled with butanol-diesel blends.

PubMed

Lamani, Venkatesh Tavareppa; Yadav, Ajay Kumar; Gottekere, Kumar Narayanappa

2017-10-01

Nitrogen oxides and smoke are the substantial emissions for the diesel engines. Fuels comprising high-level oxygen content can have low smoke emission due to better oxidation of soot. The objective of the paper is to assess the potential to employ oxygenated fuel, i.e., n-butanol and its blends with the neat diesel from 0 to 30% by volume. The experimental and computational fluid dynamic (CFD) simulation is carried out to estimate the performance, combustion, and exhaust emission characteristics of n-butanol-diesel blends for various injection timings (9°, 12°, 15°, and 18°) using modern twin-cylinder, four-stroke, common rail direct injection (CRDI) engine. Experimental results reveal the increase in brake thermal efficiency (BTE) by ~ 4.5, 6, and 8% for butanol-diesel blends of 10% (Bu10), 20% (Bu20), and 30% (Bu30), respectively, compared to neat diesel (Bu0). Maximum BTE for Bu0 is 38.4%, which is obtained at 12° BTDC; however, for Bu10, Bu20 and Bu30 are 40.19, 40.9, and 41.7%, which are obtained at 15° BTDC, respectively. Higher flame speed of n-butanol-diesel blends burn a large amount of fuel in the premixed phase, which improves the combustion as well as emission characteristics. CFD and experimental results are compared and validated for all fuel blends for in-cylinder pressure and nitrogen oxides (NO x ), and found to be in good agreement. Both experimental and simulation results witnessed in reduction of smoke opacity, NO x , and carbon monoxide emissions with the increasing n-butanol percentage in diesel fuel.

The selective catalytic reduction of NO x over Ag/Al 2O 3 with isobutanol as the reductant

DOE PAGES

Brookshear, Daniel William; Pihl, Josh A.; Toops, Todd J.; ...

2016-02-13

Here, this study investigates the potential of isobutanol (iBuOH) as a reductant for the selective catalytic reduction (SCR) of NO x over 2 wt% Ag/Al 2O 3 between 150 and 550 °C and gas hourly space velocities (GHSV) between 10,000 and 35,000 h -1. The feed gas consists of 500 ppm NO, 5% H 2O, 10% O 2, and 375-1500 ppm iBuOH (C 1:N ratios of 3-12); additionally, blends of 24 and 48% iBuOH in gasoline are evaluated. Over 90% NO x conversion is achieved between 300 and 400 C using pure iBuOH, including a 40% peak selectivity towards NHmore » 3 that could be utilized in a dual HC/NH 3 SCR configuration. The iBuOH/gasoline blends are only able to achieve greater than 90% NOx conversion when operated at a GHSV of 10,000 h -1 and employing a C 1:N ratio of 12. Iso-butyraldehyde and NO 2 appear to function as intermediates in the iBuOH-SCR mechanism, which mirrors the mechanism observed for EtOH-SCR. In general, the performance of iBuOH in the SCR of NO x over a Ag/Al 2O 3 catalyst is comparable with that of EtOH, although EtOH/gasoline blends display higher NO x reduction than iBuOH/gasoline blends. The key parameter in employing alcohols in SCR appears to be the C-OH:N ratio rather than the C 1:N ratio.« less

Impact on long-term OS of conditioning regimen in allogeneic BMT for children with AML in first CR: TBI+CY versus BU+CY: a report from the Société Française de Greffe de Moelle et de Thérapie Cellulaire.

PubMed

de Berranger, E; Cousien, A; Petit, A; Peffault de Latour, R; Galambrun, C; Bertrand, Y; Salmon, A; Rialland, F; Rohrlich, P-S; Vannier, J-P; Lutz, P; Yakouben, K; Duhamel, A; Bruno, B; Michel, G; Dalle, J-H

2014-03-01

Allogeneic hematopoietic SCT (HSCT) appears to be an efficient tool to cure high-risk AML in first CR but the choice between BU-based or TBI-based conditioning regimens still remains controversial. In order to analyze the impact of conditioning regimen on long-term survival, we conducted a retrospective analysis from French registry data including all consecutive patients under 18 years old (n=226) from 1980 to 2004 transplanted for AML in CR1 from sibling (n=142) or matched unrelated donors and given either TBI-1200 cGy and CY 120 mg/kg (TBI-Cy, n=84) or BU 16 mg/kg and CY 200 mg/kg (BuCy200, n=142). Patient subgroups were comparable for all criteria except for median age at diagnosis and HSCT and for donor type. Both 5-year OS and disease-free survival (DFS) were significantly better in BuCy200 group (P=0.02 and 0.005, respectively). In multivariate analysis, both HLA matching and BuCy200 appeared as good prognostic factors for treatment-related mortality and DFS. Grade 2-4 acute GvHD and chronic GvHD rates were statistically higher in TBI-Cy group than in Bu-Cy200 one with a RR at 2 (P=0.002). In total, Bu-Cy200 conditioning regimen gives better outcome compared with TBI-Cy irrespective of the stem cell source and the donor type.

Two pathways for electrocatalytic oxidation of hydrogen by a nickel bis(diphosphine) complex with pendant amines in the second coordination sphere.

PubMed

Yang, Jenny Y; Smith, Stuart E; Liu, Tianbiao; Dougherty, William G; Hoffert, Wesley A; Kassel, W Scott; Rakowski DuBois, M; DuBois, Daniel L; Bullock, R Morris

2013-07-03

A nickel bis(diphosphine) complex containing pendant amines in the second coordination sphere, [Ni(P(Cy)2N(t-Bu)2)2](BF4)2 (P(Cy)2N(t-Bu)2 = 1,5-di(tert-butyl)-3,7-dicyclohexyl-1,5-diaza-3,7-diphosphacyclooctane), is an electrocatalyst for hydrogen oxidation. The addition of hydrogen to the Ni(II) complex gives three isomers of the doubly protonated Ni(0) complex [Ni(P(Cy)2N(t-Bu)2H)2](BF4)2. Using the pKa values and Ni(II/I) and Ni(I/0) redox potentials in a thermochemical cycle, the free energy of hydrogen addition to [Ni(P(Cy)2N(t-Bu)2)2](2+) was determined to be -7.9 kcal mol(-1). The catalytic rate observed in dry acetonitrile for the oxidation of H2 depends on base size, with larger bases (NEt3, t-BuNH2) resulting in much slower catalysis than n-BuNH2. The addition of water accelerates the rate of catalysis by facilitating deprotonation of the hydrogen addition product before oxidation, especially for the larger bases NEt3 and t-BuNH2. This catalytic pathway, where deprotonation occurs prior to oxidation, leads to an overpotential that is 0.38 V lower compared to the pathway where oxidation precedes proton movement. Under the optimal conditions of 1.0 atm H2 using n-BuNH2 as a base and with added water, a turnover frequency of 58 s(-1) is observed at 23 °C.

1-Butanol absorption in poly(styrene-divinylbenzene) ion exchange resins for catalysis.

PubMed

Pérez-Maciá, M A; Curcó, D; Bringué, R; Iborra, M; Rodríguez-Ropero, F; van der Vegt, N F A; Aleman, Carlos

2015-12-21

The swelling behaviour of poly(styrene-co-divinylbenzene), P(S-DVB), ion exchange resins in 1-butanol (BuOH) has been studied by means of atomistic classical molecular dynamics simulations (MD). The topological characteristics reported for the resin in the dry state, which exhibited complex internal loops (macropores), were considered for the starting models used to examine the swelling induced by BuOH contents ranging from 10% to 50% w/w. Experimental measurements using a laser diffraction particle size analyzer indicate that swelling causes a volume variation with respect to the dry resin of 21%. According to MD simulations, such a volume increment corresponds to a BuOH absorption of 31-32% w/w, which is in excellent agreement with the indirect experimental estimation (i.e. 31% w/w). Simulations reveal that, independently of the content of BuOH, the density of the swelled resin is higher than that of the dry resin, evidencing that the alcohol provokes important structural changes in the polymeric matrix. Thus, BuOH molecules cause a collapse of the resin macropores when the content of alcohol is ≤20% w/w. In contrast, when the concentration of BuOH is close to the experimental value (∼30% w/w), P(S-DVB) chains remain separated by pores faciliting the access of the reactants to the reaction centers. On the other hand, evaluation of both bonding and non-bonding interactions indicates that the mixing energy is the most important contribution to the absorption of BuOH into the P(S-DVB) resin. Overall, the results displayed in this work represent a starting point for the theoretical study of the catalytic conversion of BuOH into di-n-butyl ether in P(S-DVB) ion exchange resins using sophisticated electronic methods.

Sodium butyrate suppresses angiotensin II-induced hypertension by inhibition of renal (pro)renin receptor and intrarenal renin-angiotensin system.

PubMed

Wang, Lei; Zhu, Qing; Lu, Aihua; Liu, Xiaofen; Zhang, Linlin; Xu, Chuanming; Liu, Xiyang; Li, Haobo; Yang, Tianxin

2017-09-01

Butyrate, a short-chain fatty acid, is the end product of the fermentation of complex carbohydrates by the gut microbiota. Recently, sodium butyrate (NaBu) has been found to play a protective role in a number of chronic diseases. However, it is still unclear whether NaBu has a therapeutic potential in hypertension. The present study was aimed to investigate the role of NaBu in angiotensin II (Ang II)-induced hypertension and to further explore the underlying mechanism. Ang II was infused into uninephrectomized Sprague-Dawley rats with or without intramedullary infusion of NaBu for 14 days. Mean arterial blood pressure was recorded by the telemetry system. Renal tissues, serum samples, and 24-h urine samples were collected to examine renal injury and the regulation of the (pro)renin receptor (PRR) and renin. Intramedullary infusion of NaBu in Sprague-Dawley rats lowered the Ang II-induced mean arterial pressure from 129 ± 6 mmHg to 108 ± 4 mmHg (P < 0.01). This corresponded with an improvement in Ang II-induced renal injury, including urinary albumin, glomerulosclerosis, and renal fibrosis, as well as the expression of inflammatory mediators tumor necrosis factor α, interleukin 6. The renal expression of PRR, angiotensinogen, angiotensin I-converting enzyme and the urinary excretion of soluble PRR, renin, and angiotensinogen were all increased by Ang II infusion but decreased by NaBu treatment. In cultured innermedullary collecting duct cells, NaBu treatment attenuated Ang II-induced expression of PRR and renin. These results demonstrate that NaBu exerts an antihypertensive action, likely by suppressing the PRR-mediated intrarenal renin-angiotensin system.

Synthesis, structure, theoretical studies, and Ligand exchange reactions of monomeric, T-shaped arylpalladium(II) halide complexes with an additional, weak agostic interaction.

PubMed

Stambuli, James P; Incarvito, Christopher D; Bühl, Michael; Hartwig, John F

2004-02-04

A series of monomeric arylpalladium(II) complexes LPd(Ph)X (L = 1-AdPtBu2, PtBu3, or Ph5FcPtBu2 (Q-phos); X = Br, I, OTf) containing a single phosphine ligand have been prepared. Oxidative addition of aryl bromide or aryl iodide to bis-ligated palladium(0) complexes of bulky, trialkylphosphines or to Pd(dba)2 (dba = dibenzylidene acetone) in the presence of 1 equiv of phosphine produced the corresponding arylpalladium(II) complexes in good yields. In contrast, oxidative addition of phenyl chloride to the bis-ligated palladium(0) complexes did not produce arylpalladium(II) complexes. The oxidative addition of phenyl triflate to PdL2 (L = 1-AdPtBu2, PtBu3, or Q-phos) also did not form arylpalladium(II) complexes. The reaction of silver triflate with (1-AdPtBu2)Pd(Ph)Br furnished the corresponding arylpalladium(II) triflate in good yield. The oxidative addition of phenyl bromide and iodide to Pd(Q-phos)2 was faster than oxidative addition to Pd(1-AdPtBu2)2 or Pd(PtBu3)2. Several of the arylpalladium complexes were characterized by X-ray diffraction. All of the arylpalladium(II) complexes are T-shaped monomers. The phenyl ligand, which has the largest trans influence, is located trans to the open coordination site. The complexes appear to be stabilized by a weak agostic interaction of the metal with a ligand C-H bond positioned at the fourth-coordination site of the palladium center. The strength of the Pd.H bond, as assessed by tools of density functional theory, depended upon the donating properties of the ancillary ligands on palladium.

Number of Blades-up Runs Using JetStream XC Atherectomy for Optimal Tissue Debulking in Patients with Femoropopliteal Artery In-Stent Restenosis.

PubMed

Shammas, Nicolas W; Shammas, Gail A; Aasen, Nicole; Jarvis, Gary

2015-12-01

Rotational atherectomy with the use of the JetStream XC device is indicated for treatment of infrainguinal arterial obstructive disease. The number of blades-up (BU) runs needed for optimal tissue debulking in femoropopliteal in-stent restenosis (ISR) is unknown. In the present series, 6 patients (15 lesions) were treated for femoropopliteal ISR with the JetStream XC device. Minimal luminal diameter or percent stenosis improved significantly from baseline after 2 BU runs, but no further gain was seen between 2 and 4 BU runs (P > .05). However, adjunctive balloon angioplasty reduced percent stenosis significantly following BU runs. In conclusion, the JetStream XC device achieved optimal acute angiographic results in treating femoropopliteal ISR following 2 BU runs and adjunctive balloon angioplasty. Copyright © 2015 SIR. Published by Elsevier Inc. All rights reserved.

Coordination Polymers of 5-Alkoxy Isophthalic Acids

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCormick, Laura J.; Morris, Samuel A.; Slawin, Alexandra M. Z.

The topology of coordination polymers containing 5-alkoxy isophthalic acids and first row transition metals was found to be dependent on the combination of solvent system used and length of the alkyl chain. Four different framework types were thus identified: Phase A, M 6(ROip) 5(OH) 2(H 2O) 4·xH 2O (M = Co and R = Et, Pr, or nBu, or M = Zn and R = Et); Phase B,M 2(ROip) 2(H 2O) (M = Co or Zn and R = Et, Pr, nBu, or iBu, or M = Mn and R = nBu or iBu); Phase C, Zn 3(EtOip) 2(OH) 2;more » and Phase D, Zn 2(EtOip) 2(H 2O) 3. Preliminary screening of the NO storage and release capabilities of the Co-containing materials is also reported.« less

Coordination Polymers of 5-Alkoxy Isophthalic Acids

DOE PAGES

McCormick, Laura J.; Morris, Samuel A.; Slawin, Alexandra M. Z.; ...

2016-08-23

The topology of coordination polymers containing 5-alkoxy isophthalic acids and first row transition metals was found to be dependent on the combination of solvent system used and length of the alkyl chain. Four different framework types were thus identified: Phase A, M 6(ROip) 5(OH) 2(H 2O) 4·xH 2O (M = Co and R = Et, Pr, or nBu, or M = Zn and R = Et); Phase B,M 2(ROip) 2(H 2O) (M = Co or Zn and R = Et, Pr, nBu, or iBu, or M = Mn and R = nBu or iBu); Phase C, Zn 3(EtOip) 2(OH) 2;more » and Phase D, Zn 2(EtOip) 2(H 2O) 3. Preliminary screening of the NO storage and release capabilities of the Co-containing materials is also reported.« less

[Particulate distribution characteristics of Chinese phrase V diesel engine based on butanol-diesel blends].

PubMed

Lou, Di-Ming; Xu, Ning; Fan, Wen-Jia; Zhang, Tao

2014-02-01

With a common rail diesel engine without any modification and the engine exhaust particle number and particle size analyzer EEPS, this study used the air-fuel ratio to investigate the particulate number concentration, mass concentration and number distribution characteristics of a diesel engine fueled with butanol-diesel blends (Bu10, Bu15, Bu20, Bu30 and Bu40) and petroleum diesel. The results show: for all test fuels, the particle number distributions turn to be unimodal. With the increasing of butanol, numbers of nucleation mode particles and small accumulation mode particle decrease. At low speed and low load conditions, the number of large accumulation mode particle increases slightly, but under higher speed and load conditions, the number does not increase. When the fuels contain butanol, the total particle number concentration and mass concentration in all conditions decrease and that is more obvious at high speed load.

Changes in nuclear morphology and chromatin texture of basal keratinocytes in melasma.

PubMed

Brianezi, G; Handel, A C; Schmitt, J V; Miot, L D B; Miot, H A

2015-04-01

The pathogenesis of melasma and the role of keratinocytes in disease development and maintenance are not completely understood. Dermal abnormalities, the expression of inflammatory mediators, growth factors, epithelial expression of melanocortin and sexual hormones receptors suggest that not only melanocytes, but entire epidermal melanin unit is involved in melasma physiopathology. To compare nuclear morphological features and chromatin texture between basal keratinocytes in facial melasma and adjacent normal skin. We took facial skin biopsies (2 mm melasma and adjacent normal skin) from women processed for haematoxylin and eosin. Thirty non-overlapping basal keratinocyte nuclei were segmented and descriptors of area, highest diameter, perimeter, circularity, pixel intensity, profilometric index (Ra) and fractal dimension were extracted using ImageJ software. Basal keratinocyte nuclei from facial melasma epidermis displayed larger size, irregular shape, hyperpigmentation and chromatin heterogeneity by fractal dimension than perilesional skin. Basal keratinocytes from facial melasma display changes in nuclear form and chromatin texture, suggesting that the phenotype differences between melasma and adjacent facial skin can result from complete epidermal melanin unit alterations, not just hypertrophic melanocytes. © 2014 European Academy of Dermatology and Venereology.

A Study of the Radio-Frequency Radiation from the Sun

DTIC Science & Technology

1949-07-13

8217 ^ DISTRIBUTION GNR Attn: Code 470 BuOrd BuAer Attn; Code TD -4 BuShips CNO Attn: OP-413 CO, ONR, Boston Dir., USNEL CDR., USNOTS Attn: Reports...OD rH »H ^H o o o o o ^ rH fH iH rl K ä 5 1^1» (> O ^ CM flj t^- LA >0 -O

40 CFR 721.1325 - Benzene, 1-(1-methyl-bu-toxy)-4-nitro-.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Benzene, 1-(1-methyl-bu-toxy)-4-nitro... Substances § 721.1325 Benzene, 1-(1-methyl-bu-toxy)-4-nitro-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 1-(1-methylbutoxy)-4-nitro- (PMN P...

40 CFR 721.1325 - Benzene, 1-(1-methyl-bu-toxy)-4-nitro-.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Benzene, 1-(1-methyl-bu-toxy)-4-nitro... Substances § 721.1325 Benzene, 1-(1-methyl-bu-toxy)-4-nitro-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 1-(1-methylbutoxy)-4-nitro- (PMN P...

40 CFR 721.1325 - Benzene, 1-(1-methyl-bu-toxy)-4-nitro-.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzene, 1-(1-methyl-bu-toxy)-4-nitro... Substances § 721.1325 Benzene, 1-(1-methyl-bu-toxy)-4-nitro-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 1-(1-methylbutoxy)-4-nitro- (PMN P...

40 CFR 721.1325 - Benzene, 1-(1-methyl-bu-toxy)-4-nitro-.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Benzene, 1-(1-methyl-bu-toxy)-4-nitro... Substances § 721.1325 Benzene, 1-(1-methyl-bu-toxy)-4-nitro-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 1-(1-methylbutoxy)-4-nitro- (PMN P...

40 CFR 721.1325 - Benzene, 1-(1-methyl-bu-toxy)-4-nitro-.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Benzene, 1-(1-methyl-bu-toxy)-4-nitro... Substances § 721.1325 Benzene, 1-(1-methyl-bu-toxy)-4-nitro-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzene, 1-(1-methylbutoxy)-4-nitro- (PMN P...

Study on the Pauropoda from Tibet, China. Part I. The genera Decapauropus and Hemipauropus (Myriapoda).

PubMed

Qian, Chang-Yuan; Bu, Yun; Dong, Yan; Luan, Yun-Xia

2018-01-01

Three new species of family Pauropodidae: Decapauropus biconjugarus Qian & Bu, sp. n. , D. tibeticus Qian & Bu, sp. n. and Hemipauropus quadrangulus Qian & Bu, sp. n. are described and illustrated from southeastern Tibet, China. The genus Hemipauropus is recorded for the first time from China. This is the second report of pauropods from Tibet.

An unusual alkylidyne homologation.

PubMed

Han, Yong-Shen; Hill, Anthony F; Kong, Richard Y

2018-02-27

The reaction of [W([triple bond, length as m-dash]CH)Br(CO) 2 (dcpe)] (dcpe = 1,2-bis(dicyclohexylphosphino)ethane) with t BuLi and SiCl 4 affords the trichlorosilyl ligated neopentylidyne complex [W([triple bond, length as m-dash]C t Bu)(SiCl 3 )(CO) 2 (dcpe)]. This slowly reacts with H 2 O to afford [W([triple bond, length as m-dash]CCH 2 t Bu)Cl 3 (dcpe)] and ultimately H 2 C[double bond, length as m-dash]CH t Bu via an unprecedented alkylidyne homologation in which coordinated CO is the source of the additional carbon atom with potential relevance to the Fischer-Tropsch process.

Novel tetrahydrocarbazole benzyl pyridine hybrids as potent and selective butryl cholinesterase inhibitors with neuroprotective and β-secretase inhibition activities.

PubMed

Ghobadian, Roshanak; Mahdavi, Mohammad; Nadri, Hamid; Moradi, Alireza; Edraki, Najmeh; Akbarzadeh, Tahmineh; Sharifzadeh, Mohammad; Bukhari, Syed Nasir Abbas; Amini, Mohsen

2018-05-23

Butyrylcholinesterase (BuChE) inhibitors have become interesting target for treatment of Alzheimer's disease (AD). A series of dual binding site BuChE inhibitors were designed and synthesized based on 2,3,4,9-tetrahydro-1H-carbazole attached benzyl pyridine moieties. In-vitro assay revealed that all of the designed compounds were selective and potent BuChE inhibitors. The most potent BuChE inhibitor was compound 6i (IC 50  = 0.088 ± 0.0009 μM) with the mixed-type inhibition. Docking study revealed that 6i is a dual binding site BuChE inhibitor. Also, Pharmacokinetic properties for 6i were accurate to Lipinski's rule. In addition, compound 6i demonstrated neuroprotective and β-secretase (BACE1) inhibition activities. This compound could also inhibit AChE-induced and self-induced Aβ peptide aggregation at concentration of 100 μM and 10 μM respectively. Generally, the results are presented as new potent selective BuChE inhibitors with a therapeutic potential for the treatment of AD. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Intestinal alkaline phosphatase and sodium butyrate may be beneficial in attenuating LPS-induced intestinal inflammation.

PubMed

Melo, A D B; Silveira, H; Bortoluzzi, C; Lara, L J; Garbossa, C A P; Preis, G; Costa, L B; Rostagno, M H

2016-10-17

In this study, we evaluated the effect of intestinal alkaline phosphatase (IAP) and sodium butyrate (NaBu) on lipopolysaccharide (LPS)-induced intestinal inflammation. Intestinal alkaline phosphatase and RelA/p65 (NF-κB) gene expressions in porcine jejunum explants were evaluated following exposure to sodium butyrate (NaBu) and essential oil from Brazilian red pepper (EO), alone or in combination with NaBu, as well as exogenous IAP with or without LPS challenge. Five piglets weighing approximately 20 kg each were sacrificed, and their jejunum were extracted. The tissues were segmented into 10 parts, which were exposed to 10 treatments. Gene expressions of IAP and RelA/p65 (NF-κB) in jejunal explants were evaluated via RT-PCR. We found that EO, NaBu, and exogenous IAP were able to up-regulate endogenous IAP and enhance RelA/p65 (NF-κB) gene expression. However, only NaBu and exogenous IAP down-regulated LPS-induced inflammatory response via RelA/p65 (NF-κB). In conclusion, we demonstrated that exogenous IAP and NaBu may be beneficial in attenuating LPS-induced intestinal inflammation.

Buruli ulcer in Nigeria: results of a pilot case study in three rural districts.

PubMed

Ukwaja, Kingsley N; Meka, Anthony O; Chukwuka, Alphonsus; Asiedu, Kingsley B; Huber, Kristina L; Eddyani, Miriam; Chukwu, Joseph N; Anyim, Moses C; Nwafor, Charles C; Oshi, Daniel C; Madichie, Nelson O; Ekeke, Ngozi; Njoku, Martin; Ntana, Kentigern

2016-04-22

Buruli ulcer (BU), also known as Mycobacterium ulcerans disease, is the third most common mycobacterial disease worldwide. Although BU disease has been diagnosed among Nigerians in neighbouring West African countries, data on the burden of the disease in Nigeria itself are scanty. This study aimed to assess the magnitude and epidemiology of BU in the South South region of Nigeria. We conducted a cross-sectional survey in the Ogoja territory (comprising 31 communities). We undertook sensitisation programmes centred on BU in 10 of the communities. Participants were asked to identify community members with long-standing ulcers, who were then invited for evaluation. We also contacted traditional healers to refer their clients who had non-healing ulcers. All suspected cases had a full clinical evaluation and laboratory testing. Confirmed cases were given treatment in a referral hospital in the territory. We diagnosed 41 clinical BU cases; 36 (87.8 %) of which were confirmed by quantitative polymerase chain reaction (qPCR). These 36 PCR-confirmed cases were diagnosed in a total population of 192,169 inhabitants. Therefore, the estimated crude prevalence of BU was 18.7 per 100,000 population, varying from 6.0 to 41.4 per 100,000 in the districts surveyed. The majority (66.7 %) of the cases were females. About 92 % of the BU lesions were located on the patients' extremities. No differences were observed between the sexes in terms of the location of the lesions. The age of the patients ranged from four to 60 years, with a median age of 17 years. All 35 (100 %) patients who consented to treatment completed chemotherapy as prescribed. Of the treated cases, 29 (82.9 %) needed and received surgery. All cases healed, but 29 (82.9 %) had some limitations in movement. Healing with limitations in movement occurred in 18/19 (94.7 %) and 8/10 (80.0 %) of patients with lesions >15 cm (Category III) and 6-15 cm in diameter (Category II), respectively. The median duration of treatment was 130 (87-164) days for children and 98 (56-134) days for adults (p = 0.15). In Nigeria, BU is endemic but its severity is underestimated-at least in the study setting. There is a need to identify and map BU endemic regions in Nigeria. A comprehensive BU control programme is also urgently needed.

Protection by butyrylcholinesterase against organophosphorus poisoning in nonhuman primates. (Reannouncement with new availability information)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Broomfield, C.A.; Maxwell, D.M.; Solana, R.P.

1991-12-31

Butyrylcholinesterase (BuChE) was examined as an in vivo exogenous scavenger for highly toxic organophosphorus (OP) poisons. Protection studies with equine BuChE were carried out in rhesus monkeys trained to perform a Serial Probe Recognition task. The pharmacokinetics of equine BuChE administered i.v. in rhesus monkeys revealed an elimination T1/2 of -620 hr. Animals given 503 nmol of BuChE i.v. and then challenged with 220 to 260 nmol of soman (two LD50; a lethal dose in untreated animals) all survived with no clinical signs of OP poisoning. Serial Probe Recognition performance was depressed after enzyme administration and at 1 hr postsoman.more » However, all monkeys performed the task at base-line levels at 8 hr after soman and throughout the remainder of the experimental period. Two different monkeys each were given two doses of sarin, 183 nmol/ dose (one LD50) after 460 nmol of BuChE. No signs were observed. A third group of monkeys given 253 or 340 nmol (three and four LD50, respectively) of soman after 460 nmol of BuChE required 1 mg/kg of atropine i.v. 1 0 min postsoman, but recovered completely within 24 hr. Our results indicate that BuChE has the required properties to function as a biological scavenger to protect against the pharmacological and behavioral toxicity of OP poisons. Exogenous scavenger, butyrylcholinesterase, nerve agent.« less

Endophytes and their Potential to Deal with Co-contamination of Organic Contaminants (Toluene) and Toxic Metals (Nickel) during Phytoremediation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weyens, N.; van der Lelie, D.; Truyens, S.

The aim was to investigate if engineered endophytes that are capable of degrading organic contaminants, and deal with or ideally improve uptake and translocation of toxic metals, can improve phytoremediation of mixed organic-metal pollution. As a model system, yellow lupine was inoculated with the endophyte Burkholderia cepacia VM1468 possessing (a) the pTOM-Bu61 plasmid, coding for constitutive toluene/TCE degradation, and (b) the chromosomally inserted ncc-nre Ni resistance/sequestration system. As controls, plants were inoculated with B. vietnamiensis BU61 (pTOM-Bu61) and B. cepacia BU72 (containing the ncc-nre Ni resistance/sequestration system). Plants were exposed to mixes of toluene and Ni. Only inoculation with B.more » cepacia VM1468 resulted in decreased Ni and toluene phytotoxicity, as measured by a protective effect on plant growth and decreased activities of enzymes involved in antioxidative defence (catalase, guaiacol peroxidase, superoxide dismutase) in the roots. Besides, plants inoculated with B. cepacia VM1468 and B. vietnamiensis BU61 released less toluene through the leaves than non-inoculated plants and those inoculated with B. cepacia BU72. Ni-uptake in roots was slightly increased for B. cepacia BU72 inoculated plants. These results indicate that engineered endophytes have the potential to assist their host plant to deal with co-contamination of toxic metals and organic contaminants during phytoremediation.« less

Fmoc/Trt-amino acids: comparison to Fmoc/tBu-amino acids in peptide synthesis.

PubMed

Barlos, K; Gatos, D; Koutsogianni, S

1998-03-01

Model peptides containing the nucleophilic amino acids Trp and Met have been synthesized with the application of Fmoc/Trt- and Fmoc/tBu-amino acids, for comparison. The deprotection of the peptides synthesized using Fmoc/Trt-amino acids in all cases leads to crude peptides of higher purity than that of the same peptides synthesized using Fmoc/tBu-amino acids.

Post-exposure therapy with human butyrylcholinesterase following percutaneous VX challenge in guinea pigs.

PubMed

Mumford, Helen; E Price, Matthew; Lenz, David E; Cerasoli, Douglas M

2011-04-01

Human butyrylcholinesterase (huBuChE) has potential utility as a post-exposure therapy following percutaneous nerve agent poisoning as there is a slower absorption of agent by this route and hence a later onset of poisoning. METHODS. We used surgically implanted radiotelemetry devices to monitor heart rate, EEG, body temperature and locomotor activity in guinea pigs challenged with VX via the percutaneous route. RESULTS. Treatment with huBuChE (24.2 mg/kg, i.m.) at 30 or 120 min following percutaneous VX (~2.5 × LD(50)) protected 9 out of 10 animals from lethality. When i.m. huBuChE administration was delayed until the onset of observable signs of systemic cholinergic poisoning, only one out of six animals survived to 7 days. Survival increased to 50% when the same dose of huBuChE was given intravenously at the onset of signs of poisoning. This dose represents approximately 1/10th the stoichiometric equivalent of the dose of VX administered (0.74 mg/kg). Intramuscular administration of huBuChE (24.2 mg/kg) alone did not produce any changes in heart rate, brain electrical activity, temperature or locomotion compared to saline control. Survival following VX and huBuChE treatment was associated with minimal incapacitation and observable signs of poisoning, and the mitigation or prevention of detrimental physiological changes (e.g. seizure, bradycardia and hypothermia) observed in VX + saline-treated animals. At 7 days, cholinesterase activity in the erythrocytes and most brain areas of guinea pigs that received huBuChE at either 18 h prior to or 30 min following VX was not significantly different from that of naïve, weight-matched control animals. CONCLUSION. Percutaneous VX poisoning was successfully treated using post-exposure therapy with huBuChE bioscavenger. The opportunity for post-exposure treatment may have particular relevance in civilian settings, and this is a promising indication for the use of huBuChE.

Copper-Catalyzed Intermolecular Amidation and Imidation of Unactivated Alkanes

PubMed Central

2015-01-01

We report a set of rare copper-catalyzed reactions of alkanes with simple amides, sulfonamides, and imides (i.e., benzamides, tosylamides, carbamates, and phthalimide) to form the corresponding N-alkyl products. The reactions lead to functionalization at secondary C–H bonds over tertiary C–H bonds and even occur at primary C–H bonds. [(phen)Cu(phth)] (1-phth) and [(phen)Cu(phth)2] (1-phth2), which are potential intermediates in the reaction, have been isolated and fully characterized. The stoichiometric reactions of 1-phth and 1-phth2 with alkanes, alkyl radicals, and radical probes were investigated to elucidate the mechanism of the amidation. The catalytic and stoichiometric reactions require both copper and tBuOOtBu for the generation of N-alkyl product. Neither 1-phth nor 1-phth2 reacted with excess cyclohexane at 100 °C without tBuOOtBu. However, the reactions of 1-phth and 1-phth2 with tBuOOtBu afforded N-cyclohexylphthalimide (Cy-phth), N-methylphthalimide, and tert-butoxycyclohexane (Cy-OtBu) in approximate ratios of 70:20:30, respectively. Reactions with radical traps support the intermediacy of a tert-butoxy radical, which forms an alkyl radical intermediate. The intermediacy of an alkyl radical was evidenced by the catalytic reaction of cyclohexane with benzamide in the presence of CBr4, which formed exclusively bromocyclohexane. Furthermore, stoichiometric reactions of [(phen)Cu(phth)2] with tBuOOtBu and (Ph(Me)2CO)2 at 100 °C without cyclohexane afforded N-methylphthalimide (Me-phth) from β-Me scission of the alkoxy radicals to form a methyl radical. Separate reactions of cyclohexane and d12-cyclohexane with benzamide showed that the turnover-limiting step in the catalytic reaction is the C–H cleavage of cyclohexane by a tert-butoxy radical. These mechanistic data imply that the tert-butoxy radical reacts with the C–H bonds of alkanes, and the subsequent alkyl radical combines with 1-phth2 to form the corresponding N-alkyl imide product. PMID:24405209

Risk Factors for Buruli Ulcer in Ghana—A Case Control Study in the Suhum-Kraboa-Coaltar and Akuapem South Districts of the Eastern Region

PubMed Central

Kenu, Ernest; Nyarko, Kofi Mensah; Seefeld, Linda; Ganu, Vincent; Käser, Michael; Lartey, Margaret; Calys-Tagoe, Benedict Nii Laryea; Koram, Kwodwo; Adanu, Richard; Razum, Oliver; Afari, Edwin; Binka, Fred N.

2014-01-01

Background Buruli ulcer (BU) is a skin disease caused by Mycobacterium ulcerans. Its exact mode of transmission is not known. Previous studies have identified demographic, socio-economic, health and hygiene as well as environment related risk factors. We investigated whether the same factors pertain in Suhum-Kraboa-Coaltar (SKC) and Akuapem South (AS) Districts in Ghana which previously were not endemic for BU. Methods We conducted a case control study. A case of BU was defined as any person aged 2 years or more who resided in study area (SKC or AS District) diagnosed according to the WHO clinical case definition for BU and matched with age- (+/−5 years), gender-, and community controls. A structured questionnaire on host, demographic, environmental, and behavioural factors was administered to participants. Results A total of 113 cases and 113 community controls were interviewed. Multivariate conditional logistic regression analysis identified presence of wetland in the neighborhood (OR = 3.9, 95% CI = 1.9–8.2), insect bites in water/mud (OR = 5.7, 95% CI = 2.5–13.1), use of adhesive when injured (OR = 2.7, 95% CI = 1.1–6.8), and washing in the Densu river (OR = 2.3, 95% CI = 1.1–4.96) as risk factors associated with BU. Rubbing an injured area with alcohol (OR = 0.21, 95% CI = 0.008–0.57) and wearing long sleeves for farming (OR = 0.29, 95% CI = 0.14–0.62) showed protection against BU. Conclusion This study identified the presence of wetland, insect bites in water, use of adhesive when injured, and washing in the river as risk factors for BU; and covering limbs during farming as well as use of alcohol after insect bites as protective factors against BU in Ghana. Until paths of transmission are unraveled, control strategies in BU endemic areas should focus on these known risk factors. PMID:25411974

The spectrum of low molecular weight alpha-amylase/protease inhibitor genes expressed in the US bread wheat cultivar Butte 86

PubMed Central

2011-01-01

Background Wheat grains accumulate a variety of low molecular weight proteins that are inhibitors of alpha-amylases and proteases and play an important protective role in the grain. These proteins have more balanced amino acid compositions than the major wheat gluten proteins and contribute important reserves for both seedling growth and human nutrition. The alpha-amylase/protease inhibitors also are of interest because they cause IgE-mediated occupational and food allergies and thereby impact human health. Results The complement of genes encoding alpha-amylase/protease inhibitors expressed in the US bread wheat Butte 86 was characterized by analysis of expressed sequence tags (ESTs). Coding sequences for 19 distinct proteins were identified. These included two monomeric (WMAI), four dimeric (WDAI), and six tetrameric (WTAI) inhibitors of exogenous alpha-amylases, two inhibitors of endogenous alpha-amylases (WASI), four putative trypsin inhibitors (CMx and WTI), and one putative chymotrypsin inhibitor (WCI). A number of the encoded proteins were identical or very similar to proteins in the NCBI database. Sequences not reported previously included variants of WTAI-CM3, three CMx inhibitors and WTI. Within the WDAI group, two different genes encoded the same mature protein. Based on numbers of ESTs, transcripts for WTAI-CM3 Bu-1, WMAI Bu-1 and WTAI-CM16 Bu-1 were most abundant in Butte 86 developing grain. Coding sequences for 16 of the inhibitors were unequivocally associated with specific proteins identified by tandem mass spectrometry (MS/MS) in a previous proteomic analysis of milled white flour from Butte 86. Proteins corresponding to WDAI Bu-1/Bu-2, WMAI Bu-1 and the WTAI subunits CM2 Bu-1, CM3 Bu-1 and CM16 Bu-1 were accumulated to the highest levels in flour. Conclusions Information on the spectrum of alpha-amylase/protease inhibitor genes and proteins expressed in a single wheat cultivar is central to understanding the importance of these proteins in both plant defense mechanisms and human allergies and facilitates both breeding and biotechnology approaches for manipulating the composition of these proteins in plants. PMID:21774824

Mouse Model of Human Hereditary Pancreatitis

DTIC Science & Technology

2016-09-01

NUMBER Miklos Sahin-Toth 5e. TASK NUMBER E -Mail: miklos@bu.edu 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8...PERFORMING ORGANIZATION REPORT NUMBER Trustees of Boston University 85 E Newton St M-921 Boston MA 02118-2340 9. SPONSORING / MONITORING AGENCY NAME(S) AND...Histologically (H& E staining) the pancreas of 2-week old mice looks normal while at 3 weeks of age acini show a more disorganized architecture with acinar

Self-assembly of Zn(salphen) complexes: steric regulation, stability studies and crystallographic analysis revealing an unexpected dimeric 3,3'-t-Bu-substituted Zn(salphen) complex.

PubMed

Martínez Belmonte, Marta; Wezenberg, Sander J; Haak, Robert M; Anselmo, Daniele; Escudero-Adán, Eduardo C; Benet-Buchholz, Jordi; Kleij, Arjan W

2010-05-21

The self-assembly features of a series of (non)symmetrical Zn(salphen) complexes have been studied in detail by X-ray crystallography, NMR and UV-vis techniques. The combined data demonstrate that the stability of these dimeric assemblies and the relative position of each monomeric unit within the dinuclear structure depend on the location and combination of the aromatic ring substituents.

Unit Manning System Field Evaluation

DTIC Science & Technology

1987-09-01

13a. TYPE OF REPORT 13b. TIME COVERED 14 . DATE OF REPORT ( Year , Month, Day) 15. PAGE COUNT Scientific Report FROM TO_ 1987 September 63 16...NEUROPSYCHIATRY DEPARTMENT OF MILITARY PSYCHIATRY WASHINGTON, D.C. 20307-5100 OffrML-ON CA 4 14 024 Appiaod for pabv •b pe. Dl__bu__ o Uniied DISCLAIMEI NOTICE...people rather than on materiel and weapons systems.,A Ic -e &A’& 1984 W(hite Paper on Light Infantry divisions proposed combining three- year personnel

Dehydrogenation of secondary amines: synthesis, and characterization of rare-earth metal complexes incorporating imino- or amido-functionalized pyrrolyl ligands.

PubMed

Li, Qinghai; Zhou, Shuangliu; Wang, Shaowu; Zhu, Xiancui; Zhang, Lijun; Feng, Zhijun; Guo, Liping; Wang, Fenhua; Wei, Yun

2013-02-28

The dehydrogenation of pyrrolyl-functionalized secondary amines initiated by rare-earth metal amides was systematically studied. Reactions of the rare-earth metal amides [(Me(3)Si)(2)N](3)RE(μ-Cl)Li(THF)(3) with pyrrolyl-functionalized secondary amines 2-(t)BuNHCH(2)-5-R-C(4)H(2)NH (R = H (1), R = (t)Bu (2)) led to dehydrogenation of the secondary amines with isolation of imino-functionalized pyrrolyl rare-earth metal complexes [2-(t)BuN=CH-5-R-C(4)H(2)N](2)REN(SiMe(3))(2) (R = H, RE = Y (3a), Dy (3b), Yb (3c), Eu (3d); R = (t)Bu, RE = Y (4a), Dy (4b), Er (4c)). The mixed ligands erbium complex [2-(t)BuNCH(2)-5-(t)Bu-C(4)H(2)N]Er[2-(t)BuN=CH-5-(t)BuC(4)H(2)N](2)ClLi(2)(THF) (4c') was isolated in a short reaction time for the synthesis of complex 4c. Reaction of the deuterated pyrrolyl-functionalized secondary amine 2-((t)BuNHCHD)C(4)H(3)NH with yttrium amide [(Me(3)Si)(2)N](3)Y(μ-Cl)Li(THF)(3) further proved that pyrrolyl-amino ligands were transferred to pyrrolyl-imino ligands. Treatment of 2-((t)BuNHCH(2))C(4)H(3)NH (1) with excess (Me(3)Si)(2)NLi gave the only pyrrole deprotonated product {[η(5):η(2):η(1)-2-((t)BuNHCH(2))C(4)H(3)N]Li(2)N(SiMe(3))(2)}(2) (5), indicating that LiN(SiMe(3))(2) could not dehydrogenate the secondary amines to imines and rare-earth metal ions had a decisive effect on the dehydrogenation. The reaction of the rare-earth metal amides [(Me(3)Si)(2)N](3)RE(μ-Cl)Li(THF)(3) with 1 equiv. of more bulky pyrrolyl-functionalized secondary amine 2-[(2,6-(i)Pr(2)C(6)H(3))NHCH(2)](C(4)H(3)NH) (6) in toluene afforded the only amine and pyrrole deprotonated dinuclear rare-earth metal amido complexes {(μ-η(5):η(1)):η(1)-2-[(2,6-(i)Pr(2)C(6)H(3))NCH(2)]C(4)H(3)N]LnN(SiMe(3))(2)}(2) (RE = Nd (7a), Sm (7b), Er (7c)), no dehydrogenation of secondary amine to imine products were observed. On the basis of experimental results, a plausible mechanism for the dehydrogenation of secondary amines to imines was proposed.

Methyl transfer from Fe (and Mo) to Sn: formation of (eta(5)-C(5)H(5))M(CO)(n)Sn(t)Bu(2)Me (M = Fe, n = 2; M = Mo, n = 3) complexes from photochemical irradiation of (eta(5)-C(5)H(5))M(CO)(n)Me and (t)Bu(2)SnH(2).

PubMed

Sharma, Hemant K; Arias-Ugarte, Renzo; Metta-Magana, Alejandro; Pannell, Keith H

2010-07-07

Formation of an Sn-CH(3) bond, concomitantly with an Sn-M (M = Fe, Mo), is readily achieved from the photochemical reactions of (t)Bu(2)SnH(2) with (eta(5)-C(5)H(5))M(CO)(n)Me (M = Fe, n = 2; M = Mo, n = 3) via the intermediacy of (eta(5)-C(5)H(5))M(CO)(n)Sn(t)Bu(2)H.

Extensive massive basal-ice structures in West Antarctica relate to ice-sheet anisotropy and ice-flow

NASA Astrophysics Data System (ADS)

Ross, N.; Bingham, R. G.; Corr, H. F. J.; Siegert, M. J.

2016-12-01

Complex structures identified within both the East Antarctic and Greenland ice sheets are thought to be generated by the action of basal water freezing to the ice-sheet base, evolving under ice flow. Here, we use ice-penetrating radar to image an extensive series of similarly complex basal ice facies in West Antarctica, revealing a thick (>500 m) tectonised unit in an area of cold-based and relatively slow-flowing ice. We show that major folding and overturning of the unit perpendicular to ice flow elevates deep, warm ice into the mid ice-sheet column. Fold axes align with present ice flow, and axis amplitudes increase down-ice, suggesting long-term consistency in the direction and convergence of flow. In the absence of basal water, and the draping of the tectonised unit over major subglacial mountain ranges, the formation of the unit must be solely through the deformation of meteoric ice. Internal layer radar reflectivity is consistently greater parallel to flow compared with the perpendicular direction, revealing ice-sheet crystal anisotropy is associated with the folding. By linking layers to the Byrd ice-core site, we show the basal ice dates to at least the last glacial cycle and may be as old as the last interglacial. Deformation of deep-ice in this sector of WAIS, and potentially elsewhere in Antarctica, may be caused by differential shearing at interglacial-glacial boundaries, in a process analogous to that proposed for interior Greenland. The scale and heterogeneity of the englacial structures, and their subsequent impact on ice sheet rheology, means that the nature of ice flow across the bulk of West Antarctica must be far more complex that is currently accounted for by any numerical ice sheet model.

Absolute rate constants of alkoxyl radical reactions in aqueous solution. [Tert-butyl hydroperoxide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Erben-Russ, M.; Michel, C.; Bors, W.

1987-04-23

The pulse radiolysis technique was used to generate the alkoxyl radical derived from tert-butyl hydroperoxide (/sup t/BuOOH) in aqueous solution. The reactions of this radical with 2,2'-azinobis(3-ethyl-6-benzothiazolinesulfonate) (ABTS) and promethazine were monitored by kinetic spectroscopy. The unimolecular decay rate constant of the tert-butoxyl radical (/sup t/BuO) was determined to be 1.4 x 10/sup 6/ s/sup -1/. On the basis of this value, the rate constants for /sup t/BuO attack on quercetin, crocin, crocetin, ascorbate, isoascorbate, trolox c, glutathione, thymidine, adenosine, guanosine, and unsaturated fatty acids were determined. In addition, the reaction of /sup t/BuO with the polyunsaturated fatty acids (PUFA)more » was observed by directly monitoring the formation of the fatty acid pentadienyl radicals. Interestingly, the attack of /sup t/BuO on PUFA was found to be faster by about one order of magnitude as compared to the same reaction in a nonpolar solvent.« less

A new betasatellite associated with cotton leaf curl Burewala virus infecting tomato in India: influence on symptoms and viral accumulation.

PubMed

Kumar, Jitendra; Gunapati, Samatha; Singh, Sudhir P; Kumar, Abhinav; Lalit, Adarsh; Sharma, Naresh C; Puranik, Rekha; Tuli, Rakesh

2013-06-01

A begomovirus and its associated alpha- and betasatellite were detected in tomato plants affected with leaf curl disease. Based on a nucleotide sequence identity of 99 %, this begomovirus was designated an isolate of cotton leaf curl Burewala virus (CLCuBuV). The alphasatellite exhibited 93 % sequence identity to cotton leaf curl Burewala alphasatellite (CLCuBuA) and is hence referred to here as a variant of CLCuBuA. The detected betasatellite was recombinant in nature and showed 70 % sequence identity to the known betasatellites. Inoculation of healthy tomato with CLCuBuV plus betasatellite, either in the presence or the absence of alphasatellite, led to typical leaf curling, while inoculation with CLCuBuV in the absence of betasatellite resulted in mild symptoms. This confirmed the role of the betasatellite in expression of disease symptoms. We propose to name the newly detected betasatellite tomato leaf curl Hajipur betasatellite (ToLCHJB).

Computer simulation of the active site of human serum cholinesterase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kefang Jiao; Song Li; Zhengzheng Lu

1996-12-31

The first 3D-structure of acetylchelinesterase from Torpedo California electric organ (T.AChE) was published by JL. Sussman in 1991. We have simulated 3D-structure of human serum cholinesterase (H.BuChE) and the active site of H.BuChE. It is discovered by experiment that the residue of H.BuChE is still active site after a part of H.BuChE is cut. For example, the part of 21KD + 20KD is active site of H.BuChE. The 20KD as it is. Studies on these peptides by Hemelogy indicate that two active peptides have same negative electrostatic potential maps diagram. These negative electrostatic areas attached by acetyl choline with positivemore » electrostatic potency. We predict that 147...236 peptide of AChE could be active site because it was as 20KD as with negative electrostatic potential maps. We look forward to proving from other ones.« less

Busulfan is effective second-line therapy for older patients with Philadelphia-negative myeloproliferative neoplasms intolerant of or unresponsive to hydroxyurea.

PubMed

Douglas, Genevieve; Harrison, Claire; Forsyth, Cecily; Bennett, Michael; Stevenson, William; Hounsell, John; Ratnasingam, Sumita; Ritchie, David; Ross, David M; Grigg, Andrew

2017-01-01

Hydroxyurea (Hu) is widely used as first-line cytoreductive therapy for patients with high-risk Philadelphia-negative myeloproliferative neoplasms (Ph-neg MPN), but a small proportion of patients have refractory disease or experience adverse effects. Studies have demonstrated busulfan (Bu) to be an active first-line agent, but data on its role as second-line or later therapy are minimal. To evaluate its efficacy and safety in this context, we undertook a multicenter audit of Ph-neg MPN patients who had received Bu as therapy for Hu intolerance or failure. Of 51 patients identified, 38 (75%) achieved either complete or partial hematological response following at least one Bu cycle. Bu was generally well tolerated, with only 21/135 (15%) cycles complicated by adverse effects, predominantly cytopenia; only 6% of cycles were ceased due to treatment complications. Bu is an effective and well-tolerated agent in patients with Ph-neg MPN in the setting of Hu intolerance or unresponsiveness.

NW Lab for Integrated Systems

DTIC Science & Technology

1991-05-24

hardware data compressors. [BuBo89, BuBo90, BuBo9l] The data compression scheme of Ziv and Lempel repeatedly matches the input stream to words contained...most significantly reduce dictionary size requirements in practical Ziv - Lempel encoders, without compromising; compression . How- ever, the additional...achieve a fixed 20MB/sec data rate. Thus, our Ziv - Lempel implementation realizes a speed improvement of 10 to 20 times that of the fastest recent

Immunopathogenesis of Ocular Behçet's Disease

PubMed Central

Park, Un Chul; Kim, Tae Wan; Yu, Hyeong Gon

2014-01-01

Behçet's disease (BD) is a chronic recurrent systemic inflammatory disorder of unknown etiology characterized by oral and genital ulcerations, skin lesions, and uveitis. The ocular involvement of BD, or Behçet's uveitis (BU), is characterized by panuveitis or posterior uveitis with occlusive retinal vasculitis and tends to be more recurrent and sight threatening than other endogenous autoimmune uveitides, despite aggressive immunosuppression. Although pathogenesis of BD is unclear, researches have revealed that immunological aberrations may be the cornerstone of BD development. General hypothesis of BD pathogenesis is that inflammatory response is initiated by infectious agents or autoantigens in patients with predisposing genetic factors and perpetuated by both innate and acquired immunity. In addition, a network of immune mediators plays a substantial role in the inflammatory cascade. Recently, we found that the immunopathogenesis of BU is distinct from other autoimmune uveitides regarding intraocular effector cell profiles, maturation markers of dendritic cells, and the cytokine/chemokine environment. In addition, accumulating evidence indicates the involvement of Th17 cells in BD and BU. Recent studies on genetics and biologics therapies in refractory BU also support the immunological association with the pathogenesis of BU. In this review, we provide an overview of novel findings regarding the immunopathogenesis of BU. PMID:25061613

Thiopyridazine-Based Palladium and Platinum Boratrane Complexes.

PubMed

Holler, Stefan; Tüchler, Michael; Steller, Beate G; Belaj, Ferdinand; Veiros, Luis F; Kirchner, Karl; Mösch-Zanetti, Nadia C

2018-06-07

Palladium and platinum boratrane complexes of the type [M{B(Pn Me, tBu ) 3 }(PPh 3 )] (M = Pd 1, Pt 2b) have been prepared via the reaction of the soft scorpionate ligand potassium tris(4-methyl-6- tert-butyl-3-thiopyridazinyl)borate KTn Me, tBu with bis(triphenylphosphine)metal(II) dichloride. While reaction with the Pd precursor allowed direct isolation of a symmetric boratrane complex, the Pt analogue led to the hydrido compound [Pt{B(Pn Me, tBu ) 3 }(PPh 3 )H]Cl (2a), which after reaction with a base gave 2b. Subsequent oxidation with Br 2 and I 2 , respectively, led to the dihalide compounds of the molecular formula [M{B(Pn Me, tBu ) 3 }X 2 ] (3a,b-4a,b). Halide abstraction with Ag(SbF 6 ) further gave interesting cationic compounds of either dimeric [Pd{B(Pn Me, tBu ) 3 }X] 2 (SbF 6 ) 2 (5a,b) or monomeric [Pd{B(Pn Me, tBu ) 3 }(NCMe) 2 ](SbF 6 ) (6) nature. All compounds were spectroscopically and X-ray crystallographically characterized revealing strong metal to boron interactions. DFT calculations of 1, 2a, and 2b confirm the strong M-B interaction and a high positive charge on the metal centers.

Basal Freeze-on: An Active Component of Hydrology from the Ice Divide to the Margin

NASA Astrophysics Data System (ADS)

Bell, R. E.; Tinto, K. J.; Abdi, A.; Creyts, T. T.; Wolovick, M.; Das, I.; Ferraccioli, F.; Csatho, B. M.

2012-12-01

Subglacial hydrology is considered a key control of ice sheet dynamics. Here we show that basal freeze-on is a process that can terminate basal hydrologic networks both in the interior of East Antarctica and at the margins of the Greenland Ice Sheet. Basal freeze-on modifies the ice thickness, ice structure, and ice rheology and therefore must be considered in developing accurate understanding of how hydrology interacts with ice dynamics. In East Antarctica, the freeze-on process follows well-defined hydrologic networks within Gamburtsev Mountain valleys. The steep mountain topography strongly controls the routing of the subglacial water. Ice surface slope drives the water up the mountain valleys and freeze-on occurs at the valley heads. Freeze-on ice is characterized by distinct basal radar reflectors that emerge from the hydrologic network. Evidence that these spatially coherent reflectors demark accreted ice is the upward deflection of the overlying internal layers accompanied by thickening of base of the ice sheet. Individual accretion bodies can be 25 km wide across flow, 100 km along flow with average thicknesses of ~500m although the maximum thickness is 1100m. Regional accumulation rates near the accretion sites average 4cm/yr with low ice velocity (1.5 m/yr). The volume of the ice enclosed by the accretion ice reflectors is 45-1064 km3. The accretion occurs beneath 2200-3000m thick ice and has been persistent for at least 50,000yr. Other basal reflectors in northern Greenland appear in radar from NASA's Icebridge mission and CRESIS. To identify freeze-on ice, we use specific criteria: reflectors must originate from the bed, must be spatially continuous from line to line and the meteoric stratigraphy is deflected upward. The absence of coincident gravity anomalies indicates these reflectors define distinct packages of ice rather than frozen sediment or off-nadir subglacial topography. In the Petermann Glacier Catchment, one of the largest in northern Greenland, we have identified 14 distinct basal ice packages over a wide region. The accumulation rate (~17 cm/yr) and ice velocity (~5-200m/yr) are higher than East Antarctica. These accretion bodies are 10-50 km wide, up to 940m thick and can be traced up to 140 km. The volume of the ice enclosed by the accretion ice reflector units is ~70-300 km3. We estimate that the freeze-on process in Petermann has been active for at least 6,000yr. Water has been mapped beneath much of the Greenland ice sheet and adjacent to the inland freeze-on site flat bright reflectors are interpreted as basal water. The onset of fast flow in Petermann Glacier is associated with the development of the thickest unit of freeze-on ice. Other areas of Greenland also have basal freeze-on ice. North of Jakobshavn Isbrae where the ice sheet is ~1000 m thick, evidence exists for a nearly 10 km wide, 200 m thick unit of basal ice in airborne radar. Located close to the site where basal freeze-on outcrops at the ice sheet margin at Pakitsoq, this unit may be the result of freeze-on of water draining from a supraglacial lake. Basal freeze-on is a critical component of subglacial hydrology. The evidence for large scale freeze-on East Antarctica and many areas of Greenland indicates widespread modification of the base of the ice sheet by basal hydrology.

High resolution crystal structure of the methylcobalamin analogues ethylcobalamin and butylcobalamin by X-ray synchrotron diffraction.

PubMed

Hannibal, Luciana; Smith, Clyde A; Smith, Jessica A; Axhemi, Armend; Miller, Abby; Wang, Sihe; Brasch, Nicola E; Jacobsen, Donald W

2009-07-20

The X-ray crystal structures of the methylcobalamin (MeCbl) analogues ethylcobalamin (EtCbl) and butylcobalamin (BuCbl) are reported. The X-ray crystal structures of EtCbl and BuCbl were obtained with some of the lowest crystallographic residuals ever achieved for cobalamins (R = 0.0468 and 0.0438, respectively). The Co-C bond distances for EtCbl and BuCbl are 2.023(2) and 2.028(4) A, whereas the Co-alpha-5,6-dimethylbenzimidazole (Co-N3B) bond distances were 2.232(1) and 2.244(1) A, respectively. Although EtCbl and BuCbl displayed a longer Co-N3B bond than that observed in the naturally occurring methylcobalamin, the orientation of the alpha-5,6-dimethylbenzimidazole moiety with respect to the corrin ring did not vary substantially among the structures. The lengthening of both Co-C and Co-N3B bonds in EtCbl and BuCbl can be attributed to the "inverse" trans influence exerted by the sigma-donating alkyl groups, typically observed in alkylcobalamins. Analysis of the molecular surface maps showed that the alkyl ligands in EtCbl and BuCbl are directed toward the hydrophobic side of the corrin ring. The corrin fold angles in EtCbl and BuCbl were determined to be 14.7 degrees and 13.1 degrees, respectively. A rough correlation exists between the corrin fold angle and the length of the Co-N3B bond, and both alkylcobalamins follow the same trend.

High Resolution Crystal Structure of the Methylcobalamin Analogs Ethylcobalamin and Butylcobalamin by X-ray Synchrotron Diffraction

PubMed Central

Hannibal, Luciana; Smith, Clyde A; Smith, Jessica A.; Axhemi, Armend; Miller, Abby; Wang, Sihe; Brasch, Nicola E.; Jacobsen, Donald W.

2009-01-01

The X-ray crystal structures of the methylcobalamin (MeCbl) analogs ethylcobalamin (EtCbl) and butylcobalamin (BuCbl) are reported. The X-ray crystal structures of EtCbl and BuCbl were obtained with some of the lowest crystallographic residuals ever achieved for cobalamins (R = 0.0468 and 0.0438, respectively). The Co-C bond distances for EtCbl and BuCbl are 2.023(2) and 2.028(4) Å, whereas the Co-α-5,6-dimethylbenzimidazole (Co-N3B) bond distances were 2.232(1) and 2.244(1) Å, respectively. Although EtCbl and BuCbl displayed a longer Co-N3B bond than that observed in the naturally occurring methylcobalamin, the orientation of the α-5,6-dimethylbenzimidazole moiety with respect to the corrin ring did not vary substantially amongst the structures. The lengthening of both Co-C and Co-N3B bonds in EtCbl and BuCbl can be attributed to the “inverse” trans influence exerted by the σ-donating alkyl groups, typically observed in alkylcobalamins. Analysis of the molecular surface maps showed that the alkyl ligands in EtCbl and BuCbl are directed towards the hydrophobic side of the corrin ring. The corrin fold angles in EtCbl and BuCbl were determined to be 14.7° and 13.1°, respectively. A rough correlation exists between the corrin fold angle and the length of the Co-N3B bond, and both alkylcobalamins follow the same trend. PMID:19545130

The incubation period of Buruli ulcer (Mycobacterium ulcerans infection) in Victoria, Australia - Remains similar despite changing geographic distribution of disease.

PubMed

Loftus, Michael J; Trubiano, Jason A; Tay, Ee Laine; Lavender, Caroline J; Globan, Maria; Fyfe, Janet A M; Johnson, Paul D R

2018-03-01

Buruli ulcer (BU) is a geographically-restricted infection caused by Mycobacterium ulcerans; contact with an endemic region is the primary risk factor for disease acquisition. Globally, efforts to estimate the incubation period of BU are often hindered as most patients reside permanently in endemic areas. However, in the south-eastern Australian state of Victoria, a significant proportion of people who acquire BU are visitors to endemic regions. During a sustained outbreak of BU on the Bellarine peninsula we estimated a mean incubation period of 4.5 months. Since then cases on the Bellarine peninsula have declined but a new endemic area has developed centred on the Mornington peninsula. Retrospective review of 443 cases of BU notified in Victoria between 2013 and 2016. Telephone interviews were performed to identify all cases with a single visit to an endemic region, or multiple visits within a one month period. The incubation period was defined as the time between exposure to an endemic region and symptom onset. Data were subsequently combined with those from our earlier study incorporating cases from 2002 to 2012. Among the 20 new cases identified in short-term visitors, the mean incubation period was 143 days (4.8 months), very similar to the previous estimate of 135 days (4.5 months). This was despite the predominant exposure location shifting from the Bellarine peninsula to the Mornington peninsula. We found no association between incubation period and age, sex, location of exposure, duration of exposure to an endemic region or location of BU lesion. Our study confirms the mean incubation period of BU in Victoria to be between 4 and 5 months. This knowledge can guide clinicians and suggests that the mode of transmission of BU is similar in different geographic regions in Victoria.

The interactions of azure B, a metabolite of methylene blue, with acetylcholinesterase and butyrylcholinesterase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petzer, Anél, E-mail: 12264954@nwu.ac.za; Harvey, Brian H.; Petzer, Jacobus P.

Methylene blue (MB) is reported to possess diverse pharmacological actions and is attracting increasing attention for the treatment of neurodegenerative disorders such as Alzheimer's disease. Among the pharmacological actions of MB, is the significant inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). These activities may, at least in part, underlie MB's beneficial effects in Alzheimer's disease. MB is metabolized to yield N-demethylated products of which azure B, the monodemethyl metabolite, is the predominant species. Azure B has been shown to be pharmacologically active and also possesses a variety of biological actions. Azure B therefore may contribute to the pharmacological profile ofmore » MB. Based on these considerations, the present study investigates the possibility that azure B may, similar to MB, act as an inhibitor of human AChE and BuChE. The results document that azure B inhibits AChE and BuChE with IC{sub 50} values of 0.486 μM and 1.99 μM, respectively. The results further show that azure B inhibits AChE and BuChE reversibly, and that the modes of inhibition are most likely competitive. Although the AChE and BuChE inhibitory activities of azure B are twofold and fivefold, respectively, less potent than those recorded for MB [IC{sub 50}(AChE) = 0.214 μM; IC{sub 50}(BuChE) = 0.389 μM] under identical conditions, azure B may be a contributor to MB's in vivo activation of the cholinergic system and beneficial effects in Alzheimer's disease. - Highlights: • Methylene blue (MB) is a known inhibitor of AChE and BuChE. • Azure B, the major metabolite of MB, also is an inhibitor of AChE and BuChE. • Azure B may be a contributor to MB's in vivo activation of the cholinergic system. • Azure B may contribute to MB's potential in Alzheimer's disease therapy.« less

Binding of higher alcohols onto Mn(12) single-molecule magnets (SMMs): access to the highest barrier Mn(12) SMM.

PubMed

Lampropoulos, Christos; Redler, Gage; Data, Saiti; Abboud, Khalil A; Hill, Stephen; Christou, George

2010-02-15

Two new members of the Mn(12) family of single-molecule magnets (SMMs), [Mn(12)O(12)(O(2)CCH(2)Bu(t))(16)(Bu(t)OH)(H(2)O)(3)].2Bu(t)OH (3.2Bu(t)OH) and [Mn(12)O(12)(O(2)CCH(2)Bu(t))(16)(C(5)H(11)OH)(4)] (4) (C(5)H(11)OH is 1-pentanol), are reported. They were synthesized from [Mn(12)O(12)(O(2)CMe)(16)(H(2)O)(4)].2MeCO(2)H.4H(2)O (1) by carboxylate substitution and crystallization from the appropriate alcohol-containing solvent. Complexes 3 and 4 are new members of the recently established [Mn(12)O(12)(O(2)CCH(2)Bu(t))(16)(solv)(4)] (solv = H(2)O, alcohols) family of SMMs. Only one bulky Bu(t)OH can be accommodated into 3, and even this causes significant distortion of the [Mn(12)O(12)] core. Variable-temperature, solid-state alternating current (AC) magnetization studies were carried out on complexes 3 and 4, and they established that both possess an S = 10 ground state spin and are SMMs. However, the magnetic behavior of the two compounds was found to be significantly different, with 4 showing out-of-phase AC peaks at higher temperatures than 3. High-frequency electron paramagnetic resonance (HFEPR) studies were carried out on single crystals of 3.2Bu(t)OH and 4, and these revealed that the axial zero-field splitting constant, D, is very different for the two compounds. Furthermore, it was established that 4 is the Mn(12) SMM with the highest kinetic barrier (U(eff)) to date. The results reveal alcohol substitution as an additional and convenient means to affect the magnetization relaxation barrier of the Mn(12) SMMs without major change to the ligation or oxidation state.

40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Boric acid (H3BO3), mixed esters with... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Boric acid (H3BO3), mixed esters with... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Boric acid (H3BO3), mixed esters with... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Boric acid (H3BO3), mixed esters with... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Boric acid (H3BO3), mixed esters with... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

Polymer-Nanoparticle Hybrid Photovoltaic Research for U.S. Air Force Applications

DTIC Science & Technology

2010-01-06

6 S S O S S O II xi xiviii xii (69%) (93%) (64%) (92%) 4S SBr Br S S OO OO II S S OO aReagents and Conditions: i.THF, n- BuLi , C6H13Br, -78oC, ii...CHCl3, FeCl3 (cat.), Br2, iii. THF, n- BuLi , B(OBu)3, -78oC, 2 M HCl, iv. Toluene, 1,3-propandiol, Reflux, v. (a) Ether, n- BuLi -78oC, (b) 3...thiophenecarboxaldehyde, vi. (a) n- BuLi (2eqiv.), -23oC, I2 (3eqiv.), (b) Na2SO3 and HI solun, vii. CH2Cl2, P.C.C, r.t, viii. Cu, DMF, Reflux, ix

Eddy formation behind a coastal cape in a flow generated by transient longshore wind (Numerical experiments)

NASA Astrophysics Data System (ADS)

Zhurbas, V. M.; Kuzmina, N. P.; Lyzhkov, D. A.

2017-05-01

It is shown that the process of eddy formation behind a coastal cape essentially depends on the method by which longshore flow is generated. Numerical simulations of the flow around a cape generated by transient longshore wind have revealed different modes of eddy formation in a rotating stratified environment depending on such dimensionless parameters as the Burger and Kibel-Rossby numbers, Bu and Ro, respectively. At Ro < 0.6, depending on the magnitude of Bu, either a trapped anticyclonic or cyclonic eddy (at Bu < 0.2) or periodic eddy shedding (at Bu < 0.2) forms. The eddies are weakened and stretched along the coastline at 0.4-0.6 < Ro < 1.4 and ultimately disappear at Ro < 1.4.

A Statistical Method for Estimating Missing GHG Emissions in Bottom-Up Inventories: The Case of Fossil Fuel Combustion in Industry in the Bogota Region, Colombia

NASA Astrophysics Data System (ADS)

Jimenez-Pizarro, R.; Rojas, A. M.; Pulido-Guio, A. D.

2012-12-01

The development of environmentally, socially and financially suitable greenhouse gas (GHG) mitigation portfolios requires detailed disaggregation of emissions by activity sector, preferably at the regional level. Bottom-up (BU) emission inventories are intrinsically disaggregated, but although detailed, they are frequently incomplete. Missing and erroneous activity data are rather common in emission inventories of GHG, criteria and toxic pollutants, even in developed countries. The fraction of missing and erroneous data can be rather large in developing country inventories. In addition, the cost and time for obtaining or correcting this information can be prohibitive or can delay the inventory development. This is particularly true for regional BU inventories in the developing world. Moreover, a rather common practice is to disregard or to arbitrarily impute low default activity or emission values to missing data, which typically leads to significant underestimation of the total emissions. Our investigation focuses on GHG emissions by fossil fuel combustion in industry in the Bogota Region, composed by Bogota and its adjacent, semi-rural area of influence, the Province of Cundinamarca. We found that the BU inventories for this sub-category substantially underestimate emissions when compared to top-down (TD) estimations based on sub-sector specific national fuel consumption data and regional energy intensities. Although both BU inventories have a substantial number of missing and evidently erroneous entries, i.e. information on fuel consumption per combustion unit per company, the validated energy use and emission data display clear and smooth frequency distributions, which can be adequately fitted to bimodal log-normal distributions. This is not unexpected as industrial plant sizes are typically log-normally distributed. Moreover, our statistical tests suggest that industrial sub-sectors, as classified by the International Standard Industrial Classification (ISIC), are also well represented by log-normal distributions. Using the validated data, we tested several missing data estimation procedures, including Montecarlo sampling of the real and fitted distributions, and a per ISIC estimation based on bootstrap-calculated mean values. These results will be presented and discussed in detail. Our results suggest that the accuracy of sub-sector BU emission inventories, particularly in developing regions, could be significantly improved if they are designed and carried out to be representative sub-samples (surveys) of the actual universe of emitters. A large fraction the missing data could be subsequently estimated by robust statistical procedures provided that most of the emitters were accounted by number and ISIC.

Oxygen-atom transfer chemistry and thermolytic properties of a di-tert-butylphosphate-ligated Mn4O4 cubane.

PubMed

Van Allsburg, Kurt M; Anzenberg, Eitan; Drisdell, Walter S; Yano, Junko; Tilley, T Don

2015-03-16

[Mn4O4{O2P(OtBu)2}6] (1), an Mn4O4 cubane complex combining the structural inspiration of the photosystem II oxygen-evolving complex with thermolytic precursor ligands, was synthesized and fully characterized. Core oxygen atoms within complex 1 are transferred upon reaction with an oxygen-atom acceptor (PEt3), to give the butterfly complex [Mn4O2{O2P(OtBu)2}6(OPEt3)2]. The cubane structure is restored by reaction of the latter complex with the O-atom donor PhIO. Complex 1 was investigated as a precursor to inorganic Mn metaphosphate/pyrophosphate materials, which were studied by X-ray absorption spectroscopy to determine the fate of the Mn4O4 unit. Under the conditions employed, thermolyses of 1 result in reduction of the manganese to Mn(II) species. Finally, the related butterfly complex [Mn4O2{O2P(pin)}6(bpy)2] (pin = pinacolate) is described. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Data Systems Task Analysis.

DTIC Science & Technology

1979-08-01

WHAT YOU DO IN YOUR PRESENT JOB. IdiS IS hQ A E&T. NEITHER YCU, YOUR CCMMANDER, NOR YOUR UNIT WILL BE EVALUATED , IN ANY WAY, CN THE INFORMATICN YCU...ACCOLNTING MACHINE (PCAM) OPERATOR 336. EAM/PCAM SUPERVISOR 231. EAM/PCAM WIRING TECI-NICIAN )38. EQUIPMENT MANAGEMENT TECFNICIAN 339. EVALUATION AND...R RAMO .4 12. BUNKER RAMC 13) 13. BUNKER RAMO 2)) 14. aJNKER RAMU 1563 15. BUhROdGHS 263 16. BuRROUGHS B d)) 17. BURROUGHS b35 .J 18. BjRROUGHS 847

Synthesis and some coordination chemistry of the PSnP pincer-type stannylene Sn(NCH2PtBu2)2C6H4, attempts to prepare the PSiP analogue, and the effect of the E atom on the molecular structures of E(NCH2PtBu2)2C6H4 (E = C, Si, Ge, Sn).

PubMed

Brugos, Javier; Cabeza, Javier A; García-Álvarez, Pablo; Pérez-Carreño, Enrique; Polo, Diego

2018-03-26

The non-donor-stabilized PSnP pincer-type stannylene Sn(NCH2PtBu2)2C6H4 (1) has been prepared by treating SnCl2 with Li2(NCH2PtBu2)2C6H4. All attempts to synthesize the analogous PSiP silylene by reduction of the (previously unknown) silanes SiCl2(NCH2PtBu2)2C6H4 (2), SiHCl(NCH2PtBu2)2C6H4 (3) and SiH(HMDS)(NCH2PtBu2)2C6H4 (4; HMDS = N(SiMe3)2) have been unsuccessful. The almost planar (excluding the tert-butyl groups) molecular structure of stannylene 1 (determined by X-ray crystallography) has been rationalized with the help of DFT calculations, which have shown that, in the series of diphosphanetetrylenes E(NCH2PtBu2)2C6H4 (E = C, Si, Ge, Sn), the most stable conformation of the compounds with E = Ge and Sn has both P atoms very close to the EN2C6H4 plane, near (interacting with) the E atom, whereas for the compounds with E = C and Si, both phosphane groups are located at one side of the EN2C6H4 plane and far away from the E atom. The size of the E atom and the strength of stabilizing donor-acceptor PE interactions (both increase on going down in group 14) are key factors in determining the molecular structures of these diphosphanetetrylenes. The syntheses of the chloridostannyl complexes [Rh{κ2Sn,P-SnCl(NCH2PtBu2)2C6H4}(η4-cod)] (5), [RuCl{κ2Sn,P-SnCl(NCH2PtBu2)2C6H4}(η6-cym)] (6) and [IrCl{κ2Sn,P-SnCl(NCH2PtBu2)2C6H4}(η5-C5Me5)] (7) have demonstrated the tendency of stannylene 1 to insert its Sn atom into M-Cl bonds of transition metal complexes and the preference of the resulting PSnP chloridostannyl group to act as a κ2Sn,P-chelating ligand, maintaining an uncoordinated phosphane fragment. X-ray diffraction data (of 6), 31P{1H} NMR data (of 5-7) and DFT calculations (on 6) are consistent with the existence of a weak PSn interaction involving the non-coordinated P atom of complexes 5-7, similar to that found in stannylene 1.

A novel orvinol analog, BU08028, as a safe opioid analgesic without abuse liability in primates.

PubMed

Ding, Huiping; Czoty, Paul W; Kiguchi, Norikazu; Cami-Kobeci, Gerta; Sukhtankar, Devki D; Nader, Michael A; Husbands, Stephen M; Ko, Mei-Chuan

2016-09-13

Despite the critical need, no previous research has substantiated safe opioid analgesics without abuse liability in primates. Recent advances in medicinal chemistry have led to the development of ligands with mixed mu opioid peptide (MOP)/nociceptin-orphanin FQ peptide (NOP) receptor agonist activity to achieve this objective. BU08028 is a novel orvinol analog that displays a similar binding profile to buprenorphine with improved affinity and efficacy at NOP receptors. The aim of this preclinical study was to establish the functional profile of BU08028 in monkeys using clinically used MOP receptor agonists for side-by-side comparisons in various well-honed behavioral and physiological assays. Systemic BU08028 (0.001-0.01 mg/kg) produced potent long-lasting (i.e., >24 h) antinociceptive and antiallodynic effects, which were blocked by MOP or NOP receptor antagonists. More importantly, the reinforcing strength of BU08028 was significantly lower than that of cocaine, remifentanil, or buprenorphine in monkeys responding under a progressive-ratio schedule of drug self-administration. Unlike MOP receptor agonists, BU08028 at antinociceptive doses and ∼10- to 30-fold higher doses did not cause respiratory depression or cardiovascular adverse events as measured by telemetry devices. After repeated administration, the monkeys developed acute physical dependence on morphine, as manifested by precipitated withdrawal signs, such as increased respiratory rate, heart rate, and blood pressure. In contrast, monkeys did not show physical dependence on BU08028. These in vivo findings in primates not only document the efficacy and tolerability profile of bifunctional MOP/NOP receptor agonists, but also provide a means of translating such ligands into therapies as safe and potentially abuse-free opioid analgesics.

High doses of the histone deacetylase inhibitor sodium butyrate trigger a stress-like response.

PubMed

Gagliano, Humberto; Delgado-Morales, Raul; Sanz-Garcia, Ancor; Armario, Antonio

2014-04-01

The hypothalamic-pituitary-adrenal (HPA) axis is activated by a wide range of stimuli, including drugs. Here we report that in male rats, a dose of sodium butyrate (NaBu) that is typically used to inhibit histone deacetylation (1200 mg/kg) increased the peripheral levels of HPA hormones and glucose. In a further experiment, we compared the effects of two different doses of NaBu (200 and 1200 mg/kg) and equimolar saline solutions on peripheral neuroendocrine markers and brain c-Fos expression to demonstrate a specific stress-like effect of NaBu that is not related to hypertonicity and to localise putatively involved brain areas. Only the high dose of NaBu increased the plasma levels of stress markers. The equimolar (hypertonic) saline solution also activated the HPA axis and the c-Fos expression in the paraventricular nucleus of the hypothalamus (PVN), a key area for the control of the HPA axis, but the effects were of a lower magnitude than those of NaBu. Regarding other brain areas, group differences in c-Fos expression were not observed in the medial prefrontal cortex or the medial amygdala, but they were observed in the central amygdala and the lateral ventral septum. However, only the latter area of the NaBu group showed enhanced c-Fos expression that was significantly higher than that after hypertonic saline. The present data indicate that high doses of NaBu appear to act as a pharmacological stressor, and this fact should be taken into account when using this drug to study the role of epigenetic processes in learning and emotional behaviour. Copyright © 2013 Elsevier Ltd. All rights reserved.

NMR spectroscopy and X-ray characterisation of cationic N-heteroaryl-pyridylamido Zr(IV) complexes: a further level of complexity for the elusive active species of pyridylamido olefin polymerisation catalysts.

PubMed

Li, Gang; Zuccaccia, Cristiano; Tedesco, Consiglia; D'Auria, Ilaria; Macchioni, Alceo; Pellecchia, Claudio

2014-01-03

New [(N(-),N,N(-))ZrR2] dialkyl complexes (N(-),N,N(-)=pyrrolyl-pyridyl-amido or indolyl-pyridyl-amido; R=Me or CH2Ph) have been synthesised and tested as pre-catalysts for ethene and propene polymerisation in combination with different activators, such as B(C6F5)3, [Ph3C][B(C6F5)4], [HNMe2Ph][B(C6F5)4] or solid AlMe3-depleted methylaluminoxane (DMAO). Polyethylene (M(w)>2 MDa and M(w)/M(n)= 1.3-1.6) has been produced if pre-catalysts were activated with 1000 equivalents of DMAO (based on Al) [activity >1000 kg(PE)(mol([Zr]) h mol atm)(-1)] or by using a higher pre-catalyst concentration and a mixture of [HNPhMe2][B(C6F5)4] (1 equiv) and AliBu2H (60 equiv). In the case of propene polymerisation, activity has been observed only if pre-catalysts were treated with an excess of AliBu2H prior to addition of DMAO, which led to highly isotactic polypropylene ([mmmm]>95%). Neutral pre-catalysts and ion pairs derived from their activation have been characterised in solution by using advanced 1D and 2D NMR spectroscopy experiments. The detection and rationalisation of intercationic NOEs clearly showed the formation of dimeric species in which some pyrrolyl or indolyl π-electron density of one unit is engaged in stabilising the metal centre of the other unit, which relegates the counterions in the second coordination sphere. The solid-state structure of the dimeric indolyl-pyridyl-amidomethylzirconium derivative, determined by X-ray diffraction studies, points toward a weak Zr···η(3)-indolyl interaction. It can be hypothesised that the formation of dimeric cationic species hampers monomer coordination (especially of less reactive α-olefins) and that addition of AliBu2H is crucial to split the homodimers. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

New cholinesterase inhibitors for Alzheimer's disease: Structure Activity Studies (SARs) and molecular docking of isoquinolone and azepanone derivatives.

PubMed

Bacalhau, Patrícia; San Juan, Amor A; Marques, Carolina S; Peixoto, Daniela; Goth, Albertino; Guarda, Cátia; Silva, Mara; Arantes, Sílvia; Caldeira, A Teresa; Martins, Rosário; Burke, Anthony J

2016-08-01

A library of isoquinolinone and azepanone derivatives were screened for both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activity. The strategy adopted included (a) in vitro biological assays, against eel AChE (EeAChE) and equine serum BuChE (EqBuChE) in order to determine the compounds IC50 and their dose-response activity, consolidated by (b) molecular docking studies to evaluate the docking poses and interatomic interactions in the case of the hit compounds, validated by STD-NMR studies. Compound (1f) was identified as one of these hits with an IC50 of 89.5μM for EeAChE and 153.8μM for EqBuChE, (2a) was identified as a second hit with an IC50 of 108.4μM (EeAChE) and 277.8μM (EqBuChE). In order to gain insights into the binding mode and principle active site interactions of these molecules, (R)-(1f) along with 3 other analogues (also as the R-enantiomer) were docked into both RhAChE and hBuChE models. Galantamine was used as the benchmark. The docking study was validated by performing an STD-NMR study of (1f) with EeAChE using galantamine as the benchmark. Copyright © 2016 Elsevier Inc. All rights reserved.

Antibacterial and synergistic effects of the n-BuOH fraction of Sophora flavescens root against oral bacteria.

PubMed

Lee, Kyung-Yeol; Cha, Su-Mi; Choi, Sung-Mi; Cha, Jeong-Dan

2017-01-01

The antibacterial activity of an extract and several fractions of Sophora flavescens (S. flavescens) root alone and in combination with antibiotics against oral bacteria was investigated by checkerboard assay and time-kill assay. The minimum inhibitory concentration/minimum bactericidal concentration (MIC/MBC) values for all examined bacteria were 0.313-2.5/0.625-2.5 μg/mL for the n-BuOH fraction, 0.625-5/1.25-10 μg/mL for the EtOAc fraction, 0.25-8/0.25-16 μg/mL for ampicillin, 0.5-256/1-512 μg/mL for gentamicin, 0.008-32/0.016-64 μg/mL for erythromycin, and 0.25-64/0.5-128 μg/mL for vancomycin. The n-butanol (n-BuOH) and ethyl acetate (EtOAc) fractions exhibited stronger antibacterial activity against oral bacteria than other fractions and extracts. The MICs and MBCs were reduced to between one half and one quarter when the n-BuOH and EtOAc fractions were combined with antibiotics. After 24 h of incubation, combination of 1/2 MIC of the n-BuOH fraction with antibiotics increased the degree of bactericidal activity. The present results suggest that n-BuOH and EtOAc extracts of S. flavescens root might be applicable as new natural antimicrobial agents against oral pathogens.

Low immunosuppressive burden after HLA-matched related or unrelated BMT using posttransplantation cyclophosphamide.

PubMed

Kanakry, Christopher G; Bolaños-Meade, Javier; Kasamon, Yvette L; Zahurak, Marianna; Durakovic, Nadira; Furlong, Terry; Mielcarek, Marco; Medeot, Marta; Gojo, Ivana; Smith, B Douglas; Kanakry, Jennifer A; Borrello, Ivan M; Brodsky, Robert A; Gladstone, Douglas E; Huff, Carol Ann; Matsui, William H; Swinnen, Lode J; Cooke, Kenneth R; Ambinder, Richard F; Fuchs, Ephraim J; de Lima, Marcos J; Andersson, Borje S; Varadhan, Ravi; O'Donnell, Paul V; Jones, Richard J; Luznik, Leo

2017-03-09

The intensive and prolonged immunosuppressive therapy required to prevent or treat graft-versus-host disease (GVHD) after allogeneic blood or marrow transplantation (alloBMT) puts patients at substantial risk for life-threatening infections, organ toxicity, and disease relapse. Posttransplantation cyclophosphamide (PTCy) can function as single-agent GVHD prophylaxis after myeloablative, HLA-matched related (MRD), or HLA-matched unrelated (MUD) donor T-cell-replete bone marrow allografting, obviating the need for additional prophylactic immunosuppression. However, patients who develop GVHD require supplemental treatment. We assessed the longitudinal requirement for immunosuppressive therapy in 339 patients treated with this transplantation platform: 247 receiving busulfan/cyclophosphamide (BuCy) conditioning (data collected retrospectively) and 92 receiving busulfan/fludarabine (BuFlu) conditioning (data collected prospectively). Approximately 50% of MRD patients and 30% of MUD patients never required immunosuppression beyond PTCy. In patients requiring further immunosuppression, typically only 1 to 2 agents were required, and the median durations of systemic pharmacologic immunosuppression for the BuCy MRD, BuFlu MRD, BuCy MUD, and BuFlu MUD groups all were 4.5 to 5 months. For these 4 groups, 1-year probabilities of being alive and off all systemic immunosuppression were 61%, 53%, 53%, and 51% and 3-year probabilities were 53%, 48%, 49%, and 56%, respectively. These data suggest that PTCy minimizes the global immunosuppressive burden experienced by patients undergoing HLA-matched alloBMT.

Fabrication and physical evaluation of a polymer-encapsulated paramagnetic probe for biomedical oximetry

PubMed Central

Meenakshisundaram, Guruguhan; Eteshola, Edward; Pandian, Ramasamy P.; Bratasz, Anna; Kuppusamy, Periannan

2009-01-01

Lithium octa-n-butoxynaphthalocyanine (LiNc-BuO) is a promising probe for biological electron paramagnetic resonance (EPR) oximetry and is being developed for clinical use. However, clinical applicability of LiNc-BuO may be hindered by potential limitations associated with biocompatibility, biodegradation, and migration of individual crystals in tissue. To overcome these limitations, we have encapsulated LiNc-BuO crystals in polydimethyl siloxane (PDMS), an oxygen-permeable and bioinert polymer, to fabricate conveniently implantable and retrievable oxygen-sensing chips. Encapsulation was performed by a simple cast-molding process, giving appreciable control over size, shape, thickness and spin density of chips. The in vitro oxygen response of the chip was linear, reproducible, and not significantly different from that of unencapsulated crystals. Cast-molding of the structurally-flexible PDMS enabled the fabrication of chips with tailored spin densities, and ensured non-exposure of embedded LiNc-BuO, mitigating potential biocompatibility/toxicological concerns. Our results establish PDMS-encapsulated LiNc-BuO as a promising candidate for further biological evaluation and potential clinical application. PMID:19291409

Synthesis, structural characterisation and magnetic studies of polymetallic iron phosphonate cages.

PubMed

Khanra, Sumit; Helliwell, Madeleine; Tuna, Floriana; McInnes, Eric J L; Winpenny, Richard E P

2009-08-21

Four new polymetallic iron(III) phosphonate cages have been made and structurally characterised. These are an octanuclear cage [Fe(8)O(3)(OH)(2)(O(2)C(t)Bu)(11)(PhCH(2)PO(3))(3)(py)(3)], a decanuclear cage [Fe(10)O(2)(OH)(8)(O(2)C(t)Bu)(10)(PhCH(2)PO(3))(4)(pip)(2)], a heterometallic cage [Fe(6)Li(5)(mu(3)-O)(2)((t)BuPO(3))(6)(O(2)C(t)Bu)(8)(MeOH)(2)(Py)(4)] and a tridecanuclear cage [Et(3)NH](2)[Fe(13)(mu(3)-O)(3)(mu(2)-OH)(7)((t)BuPO(3))(7)(Me(3)CCO(2))(14)(H(2)O)] (pip = piperidine, py = pyridine). Magnetic studies of the first three compounds show anti-ferromagnetic exchange between the iron(III) centers leading to diamagnetic ground states for the homometallic cages. For the heterometallic cage, the six Fe(III) centers are arranged in two triangles, and each triangle has an S = 1/2 spin ground state.

Agonist-evoked changes in cytosolic pH and calcium concentration in human platelets: studies in physiological bicarbonate.

PubMed

Sage, S O; Jobson, T M; Rink, T J

1990-01-01

1. Cytosolic pH (pHi) and calcium concentration ([Ca2+]i) have been investigated in the presence and absence of physiological HCO3- in human platelets co-loaded with the fluorescent indicators BCECF and Fura-2. Basal pHi and changes evoked by butyrate, thrombin, platelet activating factor (PAF), ADP and phorbol ester were investigated, as were the effects of removing external Na+. 2. In the presence of physiological HCO3- and CO2, basal pHi was 7.02 +/- 0.04 compared with 7.15 +/- 0.05 in the absence of HCO3-. Estimated cytosolic buffering power was reduced from 35.6 +/- 3.0 to 14.5 +/- 0.4 mM/pH unit by the omission of HCO3-. 3. Thrombin evoked an immediate acidification of 0.03 +/- 0.01 pH units in the presence of HCO3- and 0.07 +/- 0.01 pH units in its absence. The acidifications were followed by a slow alkalinization. The final pHi was 0.10 +/- 0.01 units above basal in the presence of HCO3- and 0.08 +/- 0.02 units above basal in the absence of HCO3-. The initial acidification was significantly greater in the absence of HCO3-. The subsequent increase in pHi was similar in the presence and absence of this ion, but the calculated loss of proton equivalents was greater in the presence of HCO3-. 4. Replacement of extracellular Na+ with N-methyl-D-glucamine resulted in a fall in basal pHi and abolished recovery from thrombin-evoked acidification in both the presence and absence of HCO3-. 5. In the presence of HCO3-, PAF and ADP evoked an intracellular acidification similar to that caused by thrombin. However, with PAF and ADP, the subsequent recovery in pHi was slow and did not rise above basal levels. Phorbol dibutyrate, an activator of protein kinase C, evoked a similar elevation in pHi of 0.04 +/- 0.01 units over 3 min in the presence and absence of HCO3-. 6. Stopped-flow fluorimetric measurements were made of both BCECF and Fura-2 fluorescence in the presence of HCO3-. In the presence and absence of external Ca2+, thrombin-evoked rises in [Ca2+]i peaked before any cytoplasmic alkalinization occurred. ADP evoked rapid elevations in [Ca2+]i, but caused no alkalinization.(ABSTRACT TRUNCATED AT 400 WORDS)

Fast-cycling unit of root turnover in perennial herbaceous plants in a cold temperate ecosystem

NASA Astrophysics Data System (ADS)

Sun, Kai; Luke McCormack, M.; Li, Le; Ma, Zeqing; Guo, Dali

2016-01-01

Roots of perennial plants have both persistent portion and fast-cycling units represented by different levels of branching. In woody species, the distal nonwoody branch orders as a unit are born and die together relatively rapidly (within 1-2 years). However, whether the fast-cycling units also exist in perennial herbs is unknown. We monitored root demography of seven perennial herbs over two years in a cold temperate ecosystem and we classified the largest roots on the root collar or rhizome as basal roots, and associated finer laterals as secondary, tertiary and quaternary roots. Parallel to woody plants in which distal root orders form a fast-cycling module, basal root and its finer laterals also represent a fast-cycling module in herbaceous plants. Within this module, basal roots had a lifespan of 0.5-2 years and represented 62-87% of total root biomass, thus dominating annual root turnover (60%-81% of the total). Moreover, root traits including root length, tissue density, and biomass were useful predictors of root lifespan. We conclude that both herbaceous and woody plants have fast-cycling modular units and future studies identifying the fast-cycling module across plant species should allow better understanding of how root construction and turnover are linked to whole-plant strategies.

Spectroscopic study of non-amphiphilic 2-(4-biphenylyl)-5-(4- tert-butylphenyl)-l,3,4-oxadiazole aggregates at air-water interface and in Langmuir-Blodgett films

NASA Astrophysics Data System (ADS)

Acharya, Somobrata; Bhattacharjee, D.; Sarkar, Jyotirmoy; Talapatra, G. B.

2004-07-01

This Letter reports the spectroscopic characteristics of a non-amphiphilic 2-(4-biphenylyl)-5-(4- tert-butylphenyl)-1,3,4-oxadiazole (buPBD) molecule, in Langmuir and Langmuir-Blodgett (LB) films mixed with polymethyl methacrylate (PMMA) as well as with arachidic acid (AA). The π- A isotherms of buPBD mixed with PMMA/AA at different molefractions show that at very low surface pressure, a phase transition corresponding to a reorientation of the buPBD molecules occur, whereas at high surface pressure, buPBD molecules form aggregates among the hydrophobic tail part of PMMA/AA. Absorption and fluorescence spectroscopic study of the mixed LB films reveal formation of different types of aggregates.

The first detection of the 3A g- state in carotenoids using resonance-Raman excitation profiles

NASA Astrophysics Data System (ADS)

Furuichi, Kentaro; Sashima, Tokutake; Koyama, Yasushi

2002-04-01

The singlet 3Ag- state that had been theoretically predicted in shorter polyenes [P. Tavan and K. Schulten J. Chem. Phys. 85 (1986) 6602; Phys. Rev. B 36 (1987) 4337] was first identified in bacterial carotenoids by measurements of resonance-Raman excitation profiles. It is almost overlapped with the 1Bu+ state in spheroidene (the number of conjugated double bonds, n=10), and located in-between the 1Bu+ and 1Bu- states in lycopene, anhydrorhodovibrin and spirilloxanthin (n=11-13). The slopes when the 2Ag--, 1Bu-- and 3Ag--state energies were expressed as linear functions of 1/(2n+1) exhibited the ratio of 2:3.1:3.8 in excellent agreement with that theoretically predicted, 2:3.1:3.7.

Dioxygen Reactivity of Biomimetic Fe(II) Complexes with Noninnocent Catecholate, o-Aminophenolate, and o-Phenylenediamine Ligands

PubMed Central

2015-01-01

This study describes the O2 reactivity of a series of high-spin mononuclear Fe(II) complexes each containing the facially coordinating tris(4,5-diphenyl-1-methylimidazol-2-yl)phosphine (Ph2TIP) ligand and one of the following bidentate, redox-active ligands: 4-tert-butylcatecholate (tBuCatH–), 4,6-di-tert-butyl-2-aminophenolate (tBu2APH–), or 4-tert-butyl-1,2-phenylenediamine (tBuPDA). The preparation and X-ray structural characterization of [Fe2+(Ph2TIP)(tBuCatH)]OTf, [3]OTf and [Fe2+(Ph2TIP)(tBuPDA)](OTf)2, [4](OTf)2 are described here, whereas [Fe2+(Ph2TIP)(tBu2APH)]OTf, [2]OTf was reported in our previous paper [Bittner et al., Chem.—Eur. J.2013,19, 9686–9698]. These complexes mimic the substrate-bound active sites of nonheme iron dioxygenases, which catalyze the oxidative ring-cleavage of aromatic substrates like catechols and aminophenols. Each complex is oxidized in the presence of O2, and the geometric and electronic structures of the resulting complexes were examined with spectroscopic (absorption, EPR, Mössbauer, resonance Raman) and density functional theory (DFT) methods. Complex [3]OTf reacts rapidly with O2 to yield the ferric-catecholate species [Fe3+(Ph2TIP)(tBuCat)]+ (3ox), which undergoes further oxidation to generate an extradiol cleavage product. In contrast, complex [4]2+ experiences a two-electron (2e–), ligand-based oxidation to give [Fe2+(Ph2TIP)(tBuDIBQ)]2+ (4ox), where DIBQ is o-diiminobenzoquinone. The reaction of [2]+ with O2 is also a 2e– process, yet in this case both the Fe center and tBu2AP ligand are oxidized; the resulting complex (2ox) is best described as [Fe3+(Ph2TIP)(tBu2ISQ)]+, where ISQ is o-iminobenzosemiquinone. Thus, the oxidized complexes display a remarkable continuum of electronic structures ranging from [Fe3+(L2–)]+ (3ox) to [Fe3+(L•–)]2+ (2ox) to [Fe2+(L0)]2+ (4ox). Notably, the O2 reaction rates vary by a factor of 105 across the series, following the order [3]+ > [2]+ > [4]2+, even though the complexes have similar structures and Fe3+/2+ redox potentials. To account for the kinetic data, we examined the relative abilities of the title complexes to bind O2 and participate in H-atom transfer reactions. We conclude that the trend in O2 reactivity can be rationalized by accounting for the role of proton transfer(s) in the overall reaction. PMID:24697567

SUBTHALAMIC NUCLEUS NEURONS DIFFERENTIALLY ENCODE EARLY AND LATE ASPECTS OF SPEECH PRODUCTION.

PubMed

Lipski, W J; Alhourani, A; Pirnia, T; Jones, P W; Dastolfo-Hromack, C; Helou, L B; Crammond, D J; Shaiman, S; Dickey, M W; Holt, L L; Turner, R S; Fiez, J A; Richardson, R M

2018-05-22

Basal ganglia-thalamocortical loops mediate all motor behavior, yet little detail is known about the role of basal ganglia nuclei in speech production. Using intracranial recording during deep brain stimulation surgery in humans with Parkinson's disease, we tested the hypothesis that the firing rate of subthalamic nucleus neurons is modulated in sync with motor execution aspects of speech. Nearly half of seventy-nine unit recordings exhibited firing rate modulation, during a syllable reading task across twelve subjects (male and female). Trial-to-trial timing of changes in subthalamic neuronal activity, relative to cue onset versus production onset, revealed that locking to cue presentation was associated more with units that decreased firing rate, while locking to speech onset was associated more with units that increased firing rate. These unique data indicate that subthalamic activity is dynamic during the production of speech, reflecting temporally-dependent inhibition and excitation of separate populations of subthalamic neurons. SIGNIFICANCE STATEMENT The basal ganglia are widely assumed to participate in speech production, yet no prior studies have reported detailed examination of speech-related activity in basal ganglia nuclei. Using microelectrode recordings from the subthalamic nucleus during a single syllable reading task, in awake humans undergoing deep brain stimulation implantation surgery, we show that the firing rate of subthalamic nucleus neurons is modulated in response to motor execution aspects of speech. These results are the first to establish a role for subthalamic nucleus neurons in encoding of aspects of speech production, and they lay the groundwork for launching a modern subfield to explore basal ganglia function in human speech. Copyright © 2018 the authors.

Kinetic analysis of butyrylcholinesterase-catalyzed hydrolysis of acetanilides.

PubMed

Masson, Patrick; Froment, Marie-Thérèse; Gillon, Emilie; Nachon, Florian; Darvesh, Sultan; Schopfer, Lawrence M

2007-09-01

The aryl-acylamidase (AAA) activity of butyrylcholinesterase (BuChE) has been known for a long time. However, the kinetic mechanism of aryl-acylamide hydrolysis by BuChE has not been investigated. Therefore, the catalytic properties of human BuChE and its peripheral site mutant (D70G) toward neutral and charged aryl-acylamides were determined. Three neutral (o-nitroacetanilide, m-nitroacetanilide, o-nitrophenyltrifluoroacetamide) and one positively charged (3-(acetamido) N,N,N-trimethylanilinium, ATMA) acetanilides were studied. Hydrolysis of ATMA by wild-type and D70G enzymes showed a long transient phase preceding the steady state. The induction phase was characterized by a hysteretic "burst". This reflects the existence of two enzyme states in slow equilibrium with different catalytic properties. Steady-state parameters for hydrolysis of the three acetanilides were compared to catalytic parameters for hydrolysis of esters giving the same acetyl intermediate. Wild-type BuChE showed substrate activation while D70G displayed a Michaelian behavior with ATMA as with positively charged esters. Owing to the low affinity of BuChE for amide substrates, the hydrolysis kinetics of neutral amides was first order. Acylation was the rate-determining step for hydrolysis of aryl-acetylamide substrates. Slow acylation of the enzyme, relative to that by esters may, in part, be due suboptimal fit of the aryl-acylamides in the active center of BuChE. The hypothesis that AAA and esterase active sites of BuChE are non-identical was tested with mutant BuChE. It was found that mutations on the catalytic serine, S198C and S198D, led to complete loss of both activities. The silent variant (FS117) had neither esterase nor AAA activity. Mutation in the peripheral site (D70G) had the same effect on esterase and AAA activities. Echothiophate inhibited both activities identically. It was concluded that the active sites for esterase and AAA activities are identical, i.e. S198. This excludes any other residue present in the gorge for being the catalytic nucleophile pole.

Synthesis of Au38(SCH2CH2Ph)24, Au36(SPh-tBu)24, and Au30(S-tBu)18 Nanomolecules from a Common Precursor Mixture.

PubMed

Rambukwella, Milan; Dass, Amala

2017-10-17

Phenylethanethiol protected nanomolecules such as Au 25 , Au 38 , and Au 144 are widely studied by a broad range of scientists in the community, owing primarily to the availability of simple synthetic protocols. However, synthetic methods are not available for other ligands, such as aromatic thiol and bulky ligands, impeding progress. Here we report the facile synthesis of three distinct nanomolecules, Au 38 (SCH 2 CH 2 Ph) 24 , Au 36 (SPh-tBu) 24 , and Au 30 (S-tBu) 18 , exclusively, starting from a common Au n (glutathione) m (where n and m are number of gold atoms and glutathiolate ligands) starting material upon reaction with HSCH 2 CH 2 Ph, HSPh-tBu, and HStBu, respectively. The systematic synthetic approach involves two steps: (i) synthesis of kinetically controlled Au n (glutathione) m crude nanocluster mixture with 1:4 gold to thiol molar ratio and (ii) thermochemical treatment of the purified nanocluster mixture with excess thiols to obtain thermodynamically stable nanomolecules. Thermochemical reactions with physicochemically different ligands formed highly monodispersed, exclusively three different core-size nanomolecules, suggesting a ligand induced core-size conversion and structural transformation. The purpose of this work is to make available a facile and simple synthetic method for the preparation of Au 38 (SCH 2 CH 2 Ph) 24 , Au 36 (SPh-tBu) 24 , and Au 30 (S-tBu) 18 , to nonspecialists and the broader scientific community. The central idea of simple synthetic method was demonstrated with other ligand systems such as cyclopentanethiol (HSC 5 H 9 ), cyclohexanethiol(HSC 6 H 11 ), para-methylbenzenethiol(pMBT), 1-pentanethiol(HSC 5 H 11 ), 1-hexanethiol(HSC 6 H 13 ), where Au 36 (SC 5 H 9 ) 24 , Au 36 (SC 6 H 11 ) 24 , Au 36 (pMBT) 24 , Au 38 (SC 5 H 11 ) 24 , and Au 38 (SC 6 H 13 ) 24 were obtained, respectively.

Hydrogen storage in double clathrates with tert-butylamine.

PubMed

Prasad, Pinnelli S R; Sugahara, Takeshi; Sum, Amadeu K; Sloan, E Dendy; Koh, Carolyn A

2009-06-18

The first proof-of-concept of the formation of a double tert-butylamine (t-BuNH(2)) + hydrogen (H(2)) clathrate hydrate has been demonstrated. Binary clathrate hydrates with different molar concentrations of the large guest t-BuNH(2) (0.98-9.31 mol %) were synthesized at 13.8 MPa and 250 K, and characterized by powder X-ray diffraction and Raman microscopy. A structural transformation from sVI to sII of t-BuNH(2) hydrate was clearly observed under hydrogen pressures. Raman spectroscopic data suggested that the hydrogen molecules occupied the small cages and had similar occupancy to hydrogen in the double tetrahydrofuran (THF) + H(2) clathrate hydrate. The hydrogen storage capacity in this system was approximately 0.7 H(2) wt % at the molar concentration of t-BuNH(2) close to the sII stoichiometry.

Synthesis and biological evaluation of novel tacrine derivatives and tacrine-coumarin hybrids as cholinesterase inhibitors.

PubMed

Hamulakova, Slavka; Janovec, Ladislav; Hrabinova, Martina; Spilovska, Katarina; Korabecny, Jan; Kristian, Pavol; Kuca, Kamil; Imrich, Jan

2014-08-28

A series of novel tacrine derivatives and tacrine-coumarin heterodimers were designed, synthesized, and biologically evaluated for their potential inhibitory effect on both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Of these compounds, tacrine-coumarin heterodimer 7c and tacrine derivative 6b were found to be the most potent inhibitors of human AChE (hAChE), demonstrating IC50 values of 0.0154 and 0.0263 μM. Ligands 6b, 6c, and 7c exhibited the highest levels of inhibitory activity against human BuChE (hBuChE), demonstrating IC50 values that range from 0.228 to 0.328 μM. Docking studies were performed in order to predict the binding modes of compounds 6b and 7c with hAChE/hBuChE.

Mono- and polynuclear Co(II) silanethiolates with aliphatic diamines

NASA Astrophysics Data System (ADS)

Pladzyk, Agnieszka; Baranowska, Katarzyna

2014-01-01

Four Co(II) complexes, [Co{SSi(OtBu)3}2(dmpda)] 1, [Co{SSi(OtBu)3}2(bda)2]n2 [Co{SSi(OtBu)3}2(pda)2]n3 and [Co{SSi(OtBu)3}2(hda)2]n4 [dmpda = 3-(dimethylamino)-1-propylamine; bda = 1.4-butanediamine; pda = 1.5-pentanediamine; had = 1.6-hexanediamine] have been synthesized and characterized using X-ray diffraction. Complex 1 is mononuclear and contains Co(II) coordinated by dmpda molecule in chelating mode, whereas compounds 3 and 4 are one-dimensional polymers with pda and hda diamines as bridges between the metallic centers respectively. In all complexes tri-tert-butoxysilanethiolate residue acts as terminal S-donor ligand. Full characterization of obtained compounds 1-4 was additionally carried out with the use of IR and UV-vis spectroscopy, elemental and thermal analysis.

Chromium chains as polydentate fluoride ligands for actinides and group IV metals.

PubMed

Leng, Ji-Dong; Kostopoulos, Andreas K; Isherwood, Liam H; Ariciu, Ana-Maria; Tuna, Floriana; Vitórica-Yrezábal, Iñigo J; Pritchard, Robin G; Whitehead, George F S; Timco, Grigore A; Mills, David P; Winpenny, Richard E P

2018-05-08

The reactions of {Cr6} horseshoe chains {[nPr2NH2]3[Cr6F11(O2CtBu)10]}2, 1 and precursors of actinides and group IV metals led to a series of ring complexes [nPr2NH2][Cr7TiF6O2(O2CtBu)16], 2, [nPr2NH2][Cr6Ti2F5O3(O2CtBu)16], 3, [Cr6ThF7(O2CtBu)15 (Me2SO)], 4, [(nPr2NH2)2(Cr6Th2F12(O2CtBu)16)], 5 and [nPr2NH2][Cr6U2O2F8(O2CtBu)16(Me2SO)], 6. X-ray structure studies indicate that the {Cr6} chains maintain their structures in these complexes, acting as polydentate fluoride ligands. Their static magnetic properties were measured and fitted by isotropic exchange Hamiltonian. In accordance with 1, the magnetic exchanges between CrIII are antiferromagnetic, while the exchange interactions can be modified by the tetravalent metals. For compound 6, ferromagnetic exchanges JCr-U and JU-U are obtained. EPR spectra of compounds 2-5 were measured at Q band and were simulated. The spectrum of 2 has the same profile as {Cr7Cd} and {Cr7Zn} rings with a ground state S = 3/2. 3, 4 and 5 give similar EPR spectra with S = 0 ground states.

The n-Hexane, ethylacetate, and butanol fractions from Hydnocarpi Semen enhanced wound healing in a mice ulcer model.

PubMed

Lee, Geum Seon; Yim, Dongsool; Cheong, Jae Hoon; Kang, Tae Jin

2012-12-01

Our previous report showed that Hydnocarpi Semen (HS) extract has wound repair activity at ulcer lesion in diabetic mice. In this study, fractions of n-Hexane, ethylacetate (EtOAc), and butanol (BuOH) from HS crude extract were evaluated for their wound healing activity by using in vivo diabetic ulcer models and in vitro acute inflammation model. Although n-Hexane and EtOAc fractions promote wound healing in mice with ulcer, the BuOH fraction exhibited the most potent wound healing activity and the wound area score significantly decreased after treatment of BuOH fraction even at dose of 2 mg/kg. BuOH fraction stimulated macrophages to increase the production of nitric oxide (NO) and TNF-α. The BuOH fraction also enhanced the production of TGF-β and VEGF, which were involved in fibroblast activation and angiogenesis. The mRNA expression and activation of MMP-9 were increased by three fractions and the activity was higher in BuOH fraction-treated group compared to the other groups. The mechanism that the HS helps to promote healing of diabetic ulcer is possibly associated with the production of TNF-α, a proinflammatory cytokine, as well as the secretion of VEGF, TGF-β, and MMP-9, which were involved in proliferation of capillaries and fibroblasts. These results suggest that HS can be a new candidate material for the treatment of wound in skin ulcer.

[Multicenter investigation of bufavirus in the etiology of viral central nervous system infections of adults and children].

PubMed

Altay Koçak, Aylin; Öcal, Murat; Polat, Meltem; Kanık Yüksek, Saliha; Aktaş Tapısız, Anıl; Tezer, Hasan; Özkul, Aykut; Ergünay, Koray; Bozdayı, Gülendam; Ahmed, Kamruddin

2017-04-01

Bufavirus (BuV) is a newly-identified parvovirus in the family of Parvoviridae. Metagenomic analysis of fecal samples from children in Burkina Faso with acute diarrhea showed a highly divergent parvovirus, which was named bufavirus (BuV). The global distribution, epidemiology and genetic characteristics of BuVs infections are obscure. It was first discovered as an agent causing gastroenteritis but the association of BuV infections with various clinical presentations mostly remain to be explored. The aims of this study were to investigate probable impact of BuV in central nervous system infections in a region where it was previously reported to cause human infections and to detect enteroviruses (EV) which are reported as a cause of central nervous system infections in our country. The study was undertaken in three institutions in Ankara province, Central Anatolia, Turkey. Patients, clinically diagnosed with febrile disease and/or central nervous system infections of presumed viral etiology, were enrolled in the study with informed consent. Cerebrospinal fluid specimens were collected from 93 children attended to Gazi University Hospital and Dışkapı Yıldırım Beyazıt Hospital from October 2011-April 2015 and 33 adult patients, attended to Hacettepe University Hospital from June 2012 to March 2013. Clinical history and follow-up, physical examination and standard laboratory findings of the patients were recorded. Nucleic acid extraction was performed via commercially available spin-column assays and complementery DNA (cDNA) synthesis was performed by using commercially available cDNA synthesis kit with randomised hexamer primers. BuV detection was carried out by in house nested-polymerase chain reaction (PCR) utilized with previously-described primers. EV detection was carried out by in house PCR with pan-enterovirus primers. Seventy-four percent (93/126) and 26% (33/126) of the patients were children (0-18) and adults (19-86), respectively. In all patients, bacterial, mycobacterial and fungal cultures were negative, as well as PCR for herpes simplex virus (HSV) types 1 and 2. PCR results of all samples were negative for BuV and EV. This is the first study that evaluates a probable association of BuV and central nervous system infections. Although Parvovirus B19, a well-characterized human pathogen can rarely cause encephalitis, our findings did not confirm such an association for BuV in this preliminary investigation. However, long-term evaluation of individual cases with unknown etiology is required to reveal the relationship of the virus with specific environments.

A computational study of the CO dissociation in cyclopentadienyl ruthenium complexes relevant to the racemization of alcohols.

PubMed

Stewart, Beverly; Nyhlen, Jonas; Martín-Matute, Belén; Bäckvall, Jan-E; Privalov, Timofei

2013-01-28

The formation of an active 16-electron ruthenium sec-alkoxide complex via loss of the CO ligand is an important step in the mechanism of the racemization of sec-alcohols by (η(5)-Ph(5)C(5))Ru(CO)(2)X ruthenium complexes with X = Cl and O(t)Bu. Here we show with accurate DFT calculations the potential energy profile of the CO dissociation pathway for a series of relevant (η(5)-Ph(5)C(5))Ru(CO)(2)X complexes, where X = Cl, O(t)Bu, H and COO(t)Bu. We have found that the CO dissociation energy increases in the following order: O(t)Bu (lowest), Cl, COO(t)Bu and H (highest). Using the distance between ruthenium and C(CO), r = Ru-C(CO), as a constraint, and by optimizing all other degrees of freedom for a range of Ru-CO distances, we obtained relative energies, ΔE(r) and geometries of a sufficient number of transient structures with the elongated Ru-CO bond up to r = 3.4 Å. Our calculations provide a quantitative understanding of the CO ligand dissociation in (η(5)-Ph(5)C(5))Ru(CO)(2)Cl and (η(5)-Ph(5)C(5))Ru(CO)(2)(O(t)Bu) complexes, which is relevant to the mechanism of their catalytic activity in the racemization of alcohols. We recently reported that exchange of the CO ligand by isotopically labeled (13)CO in the Ru-O(t)Bu complex occurs twenty times faster than that in the Ru-Cl complex. This corresponds to a difference of 1.8 kcal mol(-1) in the CO dissociation energy (at room temperature). This is in very good agreement with the calculated difference between the two potential energy curves for Ru-O(t)Bu and Ru-Cl complexes, which is about 1.8-2 kcal mol(-1) around the corresponding transition states of the CO dissociation. The calculated difference in the total energy for CO dissociation in (η(5)-Ph(5)C(5))Ru(CO)(2)X complexes is related to the stabilization provided by the X group in the final 16-electron complexes, which are formed via product-like transition states. In addition to the calculated transition states of CO dissociation in Ru-O(t)Bu and Ru-Cl complexes, the calculated transient structures with the elongated Ru-CO bond provide insight into how the geometry of the ruthenium complex with a potent heteroatom donor group (X) gradually changes when one of the COs is dissociating.

Horizontal Gene Transfer to Endogenous Endophytic Bacteria from Poplar Improves Phytoremediation of Toluene

PubMed Central

Taghavi, Safiyh; Barac, Tanja; Greenberg, Bill; Borremans, Brigitte; Vangronsveld, Jaco; van der Lelie, Daniel

2005-01-01

Poplar, a plant species frequently used for phytoremediation of groundwater contaminated with organic solvents, was inoculated with the endophyte Burkholderia cepacia VM1468. This strain, whose natural host is yellow lupine, contains the pTOM-Bu61 plasmid coding for constitutively expressed toluene degradation. Noninoculated plants or plants inoculated with the soil bacterium B. cepacia Bu61(pTOM-Bu61) were used as controls. Inoculation of poplar had a positive effect on plant growth in the presence of toluene and reduced the amount of toluene released via evapotranspiration. These effects were more dramatic for VM1468, the endophytic strain, than for Bu61. Remarkably, none of the strains became established at detectable levels in the endophytic community, but there was horizontal gene transfer of pTOM-Bu61 to different members of the endogenous endophytic community, both in the presence and in the absence of toluene. This work is the first report of in planta horizontal gene transfer among plant-associated endophytic bacteria and demonstrates that such transfer could be used to change natural endophytic microbial communities in order to improve the remediation of environmental insults. PMID:16332840

Functional Characterization of a Bidirectional Plant Promoter from Cotton Leaf Curl Burewala Virus Using an Agrobacterium-Mediated Transient Assay

PubMed Central

Ashraf, Muhammad Aleem; Shahid, Ahmad Ali; Rao, Abdul Qayyum; Bajwa, Kamran Shehzad; Husnain, Tayyab

2014-01-01

The C1 promoter expressing the AC1 gene, and V1 promoter expressing the AV1 gene are located in opposite orientations in the large intergenic region of the Cotton leaf curl Burewala virus (CLCuBuV) genome. Agro-infiltration was used to transiently express putative promoter constructs in Nicotiana tabacum and Gossypium hirsutum leaves, which was monitored by a GUS reporter gene, and revealed that the bidirectional promoter of CLCuBuV transcriptionally regulates both the AC1 and AV1 genes. The CLCuBuV C1 gene promoter showed a strong, consistent transient expression of the reporter gene (GUS) in N. tabacum and G. hirsutum leaves and exhibited GUS activity two- to three-fold higher than the CaMV 35S promoter. The CLCuBuV bidirectional genepromoter is a nearly constitutive promoter that contains basic conserved elements. Many cis-regulatory elements (CREs) were also analyzed within the bidirectional plant promoters of CLCuBuV and closely related geminiviruses, which may be helpful in understanding the transcriptional regulation of both the virus and host plant. PMID:24424501

Virulence potential of Staphylococcus aureus isolates from Buruli ulcer patients.

PubMed

Amissah, Nana Ama; Chlebowicz, Monika A; Ablordey, Anthony; Tetteh, Caitlin S; Prah, Isaac; van der Werf, Tjip S; Friedrich, Alex W; van Dijl, Jan Maarten; Stienstra, Ymkje; Rossen, John W

2017-06-01

Buruli ulcer (BU) is a necrotizing infection of the skin and subcutaneous tissue caused by Mycobacterium ulcerans. BU wounds may also be colonized with other microorganisms including Staphylococcus aureus. This study aimed to characterize the virulence factors of S. aureus isolated from BU patients. Previously sequenced genomes of 21 S. aureus isolates from BU patients were screened for the presence of virulence genes. The results show that all S. aureus isolates harbored on their core genomes genes for known virulence factors like α-hemolysin, and the α- and β-phenol soluble modulins. Besides the core genome virulence genes, mobile genetic elements (MGEs), i.e. prophages, genomic islands, pathogenicity islands and a Staphylococcal cassette chromosome (SCC) were found to carry different combinations of virulence factors, among them genes that are known to encode factors that promote immune evasion, superantigens and Panton-Valentine Leucocidin. The present observations imply that the S. aureus isolates from BU patients harbor a diverse repertoire of virulence genes that may enhance bacterial survival and persistence in the wound environment and potentially contribute to delayed wound healing. Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.

Disruption of Darna pallivitta (Lepidoptera: Limacodidae) by Conventional and Mobile Pheromone Deployment

PubMed Central

Siderhurst, Matthew S.; Jang, Eric B.; Carvalho, Lori A. F. N.; Nagata, Janice T.; Derstine, Nathan T.

2015-01-01

Identification of the Darna pallivitta (Moore) pheromone component n-butyl (E)-7,9-decadienoate (E7,9-10:COOn-Bu) has made it possible to investigate communication disruption to control this lepidopteran pest. Conventional communication disruption trials showed marked decreases in the mean number of male moths captured in E7,9-10:COOnBu-treated fields compared with control fields. For traps baited with E7,9-10:COOnBu, percent disruptions were 94.4% and 92.1% for septa (1 g pheromone/ha, 1-wk trial duration) and spirals (6 g pheromone/ha, 8-wk trial duration) respectively. For traps baited with virgin female moths, percent disruption was 73.3% using septa disruptors (1 g pheromone/ha, 1-wk trial duration). Mobile communication disruption using Bactrocera cucurbitae (Coquillett) as carriers for E7,9-10:COOn-Bu was evaluated in the following three areas: fly survivorship, attraction of male moths to treated flies, and moth disruption in a small-scale field trial. Topical application of E7,9-10:COOnBu showed no significant decrease in survivorship at 50 and 80 µg/fly. However, decreased survivorship was observed at 100 µg/fly and linear regression showed E7,9-10:COOnBu dose was significantly correlated with B. cucurbitae survivorship. Traps containing honey–pheromone-fed flies attracted and caught D. pallivitta over a 1-wk period, demonstrating the attractiveness of the carrier. Releasing E7,9-10:COOnBu-fed B. cucurbitae (∼2 g pheromone/ha, 1-wk trial duration) resulted in significantly reduced trap catches in treatment fields compared with control fields on the first 2 d of the field trial. Percent disruptions were 84.7% (day 1) and 56.0% (day 2). These results suggest that both conventional communication disruption and mobile communication disruption have potential to control D. pallivitta. PMID:26078301

The Mammalian Neuronal Sodium Channel Blocker μ-Conotoxin BuIIIB has a Structured N-terminus that Influences Potency

PubMed Central

Kuang, Zhihe; Zhang, Min-Min; Gupta, Kallol; Gajewiak, Joanna; Gulyas, Jozsef; Balaram, Padmanabhan; Rivier, Jean E.; Olivera, Baldomero M.; Yoshikami, Doju; Bulaj, Grzegorz; Norton, Raymond S.

2014-01-01

Among the μ-conotoxins that block vertebrate voltage-gated sodium channels (VGSCs), some have been shown to be potent analgesics following systemic administration in mice. We have determined the solution structure of a new representative of this family, μ-BuIIIB, and established its disulfide connectivities by direct mass spectrometric collision induced dissociation fragmentation of the peptide with disulfides intact. The major oxidative folding product adopts a 1-4/2-5/3-6 pattern with the following disulfide bridges: Cys5-Cys17, Cys6-Cys23 and Cys13-Cys24. The solution structure reveals that the unique N-terminal extension in μ-BuIIIB, which is also present in μ-BuIIIA and μ-BuIIIC but absent in other μ-conotoxins, forms part of a short α-helix encompassing Glu3 to Asn8. This helix is packed against the rest of the toxin and stabilized by the Cys5-Cys17 and Cys6-Cys23 disulfide bonds. As such, the side chain of Val1 is located close to the aromatic rings of Trp16 and His20, which are located on the canonical helix that displays several residues found to be essential for VGSC blockade in related μ-conotoxins. Mutations of residues 2 and 3 in the N-terminal extension enhanced the potency of μ-BuIIIB for NaV1.3. One analog, [d-Ala2]BuIIIB, showed a 40-fold increase, making it the most potent peptide blocker of this channel characterized to date and thus a useful new tool with which to characterize this channel. Based on previous results for related μ-conotoxins, the dramatic effects of mutations at the N-terminus were unanticipated, and suggest that further gains in potency might be achieved by additional modifications of this region. PMID:23557677

The incubation period of Buruli ulcer (Mycobacterium ulcerans infection).

PubMed

Trubiano, Jason A; Lavender, Caroline J; Fyfe, Janet A M; Bittmann, Simone; Johnson, Paul D R

2013-01-01

Buruli Ulcer (BU) is caused by the environmental microbe Mycobacterium ulcerans. Despite unclear transmission, contact with a BU endemic region is the key known risk factor. In Victoria, Australia, where endemic areas have been carefully mapped, we aimed to estimate the Incubation Period (IP) of BU by interviewing patients who reported defined periods of contact with an endemic area prior to BU diagnosis. A retrospective review was undertaken of 408 notifications of BU in Victoria from 2002 to 2012. Telephone interviews using a structured questionnaire and review of notification records were performed. Patients with a single visit exposure to a defined endemic area were included and the period from exposure to disease onset determined (IP). We identified 111 of 408 notified patients (27%) who had a residential address outside a known endemic area, of whom 23 (6%) reported a single visit exposure within the previous 24 months. The median age of included patients was 30 years (range: 6 to 73) and 65% were male. 61% had visited the Bellarine Peninsula, currently the most active endemic area. The median time from symptom onset to diagnosis was 71 days (range: 34-204 days). The midpoint of the reported IP range was utilized to calculate a point estimate of the IP for each case. Subsequently, the mean IP for the cohort was calculated at 135 days (IQR: 109-160; CI 95%: 113.9-156), corresponding to 4.5 months or 19.2 weeks. The shortest IP recorded was 32 days and longest 264 days (Figure 1 & 2). IP did not vary for variables investigated. The estimated mean IP of BU in Victoria is 135 days (IQR: 109-160 days), 4.5 months. The shortest recorded was IP 34 days and longest 264 days. A greater understanding of BU IP will aid clinical risk assessment and future research.

Anti-diabetic activity of the semi-purified fractions of Averrhoa bilimbi in high fat diet fed-streptozotocin-induced diabetic rats.

PubMed

Tan, Benny Kwong Huat; Tan, Chee Hong; Pushparaj, Peter Natesan

2005-04-29

The present study was designed to investigate the hypoglycemic and hypolipidemic activities of the semi-purified fractions of an ethanolic leaf extract of Averrhoa bilimbi (ABe) in high fat diet (HFD)-streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley rats aged 10 weeks (200-250 g) were fed with a high fat diet obtained from Glen Forrest stock feeders (Western Australia) for 2 weeks prior to intraperitoneal injection with streptozotocin (STZ, 50 mg/kg). The leaves of A.bilimbi were exhaustively extracted with 80% ethanol, concentrated at 40 degrees C using a rotavapor and partitioned successively with butanol, ethylacetate and hexane to get aqueous (AF), butanol (BuF), ethylacetate (EF), and hexane fractions (HF). The fractions were freeze-dried to obtain powders of each. To investigate the effect of long term administration of the hypoglycemic fractions, diabetic animals were treated with vehicle (distilled water), AF (125 mg/kg), or BuF (125 mg/kg), twice a day for 14 days. The long term administration of AF and BuF at a dose of 125 mg/kg significantly (P < 0.05) lowered blood glucose and triglyceride concentrations when compared to the vehicle. The hepatic glycogen content was significantly higher (P < 0.05) in AF-treated rats when compared to diabetic control, however no change was found in the BuF-treated rats. Moreover, AF as well as BuF did not cause any significant change in the total cholesterol and HDL-cholesterol. There was also no difference in liver thiobarbituric acid reactive substances (TBARS) and cytochrome P450 values between AF, BuF and vehicle-treated control rats. In conclusion, the results indicate that AF is more potent than BuF in the amelioration of hyperglycemia and hyperlipidemia in HFD fed-STZ diabetic rats. Hence, AF is a potential source for the isolation of active principle(s) for oral anti-diabetic therapy.

Disruption of Darna pallivitta (Lepidoptera: Limacodidae) by Conventional and Mobile Pheromone Deployment.

PubMed

Siderhurst, Matthew S; Jang, Eric B; Carvalho, Lori A F N; Nagata, Janice T; Derstine, Nathan T

2015-01-01

Identification of the Darna pallivitta (Moore) pheromone component n-butyl (E)-7,9-decadienoate (E7,9-10:COOn-Bu) has made it possible to investigate communication disruption to control this lepidopteran pest. Conventional communication disruption trials showed marked decreases in the mean number of male moths captured in E7,9-10:COOnBu-treated fields compared with control fields. For traps baited with E7,9-10:COOnBu, percent disruptions were 94.4% and 92.1% for septa (1 g pheromone/ha, 1-wk trial duration) and spirals (6 g pheromone/ha, 8-wk trial duration) respectively. For traps baited with virgin female moths, percent disruption was 73.3% using septa disruptors (1 g pheromone/ha, 1-wk trial duration). Mobile communication disruption using Bactrocera cucurbitae (Coquillett) as carriers for E7,9-10:COOn-Bu was evaluated in the following three areas: fly survivorship, attraction of male moths to treated flies, and moth disruption in a small-scale field trial. Topical application of E7,9-10:COOnBu showed no significant decrease in survivorship at 50 and 80 µg/fly. However, decreased survivorship was observed at 100 µg/fly and linear regression showed E7,9-10:COOnBu dose was significantly correlated with B. cucurbitae survivorship. Traps containing honey-pheromone-fed flies attracted and caught D. pallivitta over a 1-wk period, demonstrating the attractiveness of the carrier. Releasing E7,9-10:COOnBu-fed B. cucurbitae (∼2 g pheromone/ha, 1-wk trial duration) resulted in significantly reduced trap catches in treatment fields compared with control fields on the first 2 d of the field trial. Percent disruptions were 84.7% (day 1) and 56.0% (day 2). These results suggest that both conventional communication disruption and mobile communication disruption have potential to control D. pallivitta. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.

Ruthenium chalcogenonitrosyl and bridged nitrido complexes containing chelating sulfur and oxygen ligands.

PubMed

Ng, Ho-Yuen; Cheung, Wai-Man; Kwan Huang, Enrique; Wong, Kang-Long; Sung, Herman H-Y; Williams, Ian D; Leung, Wa-Hung

2015-11-14

Ruthenium thio- and seleno-nitrosyl complexes containing chelating sulfur and oxygen ligands have been synthesised and their de-chalcogenation reactions have been studied. The reaction of mer-[Ru(N)Cl3(AsPh3)2] with elemental sulfur and selenium in tetrahydrofuran at reflux afforded the chalcogenonitrosyl complexes mer-[Ru(NX)Cl3(AsPh3)2] [X = S (1), Se (2)]. Treatment of 1 with KN(R2PS)2 afforded trans-[Ru(NS)Cl{N(R2PS)2}2] [R = Ph (3), Pr(i) (4), Bu(t) (5)]. Alternatively, the thionitrosyl complex 5 was obtained from [Bu(n)4N][Ru(N)Cl4] and KN(Bu(t)2PS)2, presumably via sulfur atom transfer from [N(Bu(t)2PS)2](-) to the nitride. Reactions of 1 and 2 with NaLOEt (LOEt(-) = [Co(η(5)-C5H5){P(O)(LOEt)2}3](-)) gave [Ru(NX)LOEtCl2] (X = S (8), Se (9)). Treatment of [Bu(n)4N][Ru(N)Cl4] with KN(R2PS)2 produced Ru(IV)-Ru(IV)μ-nitrido complexes [Ru2(μ-N){N(R2PS)2}4Cl] [R = Ph (6), Pr(i) (7)]. Reactions of 3 and 9 with PPh3 afforded 6 and [Ru(NPPh3)LOEtCl2], respectively. The desulfurisation of 5 with [Ni(cod)2] (cod = 1,5-cyclooctadiene) gave the mixed valance Ru(III)-Ru(IV)μ-nitrido complex [Ru2(μ-N){N(Bu(t)2PS)2}4] (10) that was oxidised by [Cp2Fe](PF6) to give the Ru(IV)-Ru(IV) complex [Ru2(μ-N){N(Bu(t)2PS)2}4](PF6) ([10]PF6). The crystal structures of 1, 2, 3, 7, 9 and 10 have been determined.

Structural transformations of sVI tert-butylamine hydrates to sII binary hydrates with methane.

PubMed

Prasad, Pinnelli S R; Sugahara, Takeshi; Sloan, E Dendy; Sum, Amadeu K; Koh, Carolyn A

2009-10-22

Binary clathrate hydrates with methane (CH(4), 4.36 A) and tert-butylamine (t-BuNH(2), 6.72 A) as guest molecules were synthesized at different molar concentrations of t-BuNH(2) (1.00-9.31 mol %) with methane at 7.0 MPa and 250 K, and were characterized by powder X-ray diffraction (PXRD) and Raman microscopy. A structural transformation from sVI to sII of t-BuNH(2) hydrate was clearly observed on pressurizing with methane. The PXRD showed sII signatures and the remnant sVI signatures were insignificant, implying the metastable nature of sVI binary hydrates. Raman spectroscopic data on these binary hydrates suggest that the methane molecules occupy the small cages and vacant large cages. The methane storage capacity in this system was nearly doubled to approximately 6.86 wt % for 5.56 mol % > t-BuNH(2) > 1.0 mol %.

Mycobacterium ulcerans Disease, Peru

PubMed Central

Guerra, Humberto; Palomino, Juan Carlos; Falconí, Eduardo; Bravo, Francisco; Donaires, Ninoska; Van Marck, Eric

2008-01-01

Eight adult patients (ages 18–58, 5 women) with Buruli ulcer (BU) confirmed by at least 2 diagnostic methods were seen in a 10-year period. Attempts to culture Mycobacterium ulcerans failed. Five patients came from jungle areas, and 3 from the swampy northern coast of Peru. The patients had 1–5 lesions, most of which were on the lower extremities. One patient had 5 clustered gluteal lesions; another patient had 2 lesions on a finger. Three patients were lost to follow-up. All 5 remaining patients had moderate disease. Diverse treatments (antituberculous drugs, World Health Organization [WHO] recommended antimicrobial drug treatment for BU, and for 3 patients, excision surgery) were successful. Only 1 patient (patient 7) received the specific drug treatment recommended by WHO. BU is endemic in Peru, although apparently infrequent. Education of populations and training of health workers are first needed to evaluate and understand the full extent of BU in Peru. PMID:18325248

Ries Bunte Breccia revisited: Indications for the presence of water in Itzing and Otting drill cores and implications for the emplacement process

NASA Astrophysics Data System (ADS)

Pietrek, Alexa; Kenkmann, Thomas

2016-07-01

We reassessed two drill cores of the Bunte Breccia deposits of the Ries crater, Germany. The objectives of our study were the documentation of evidence for water in the Bunte Breccia, the evaluation of how that water influenced the emplacement processes, and from which preimpact water reservoir it was derived. The Bunte Breccia in both cores can be structured into a basal layer composed mainly of local substrate material, overlain by texturally and compositionally diverse, crater-derived breccia units. The basal layer is composed of the youngest sediments (Tertiary clays and Upper Jurassic limestone) and has a razor-sharp boundary to the upper breccia units, which are composed of older rocks of Upper Jurassic to Upper Triassic age. Sparse material exchange occurred between the basal layer and the rest of the Bunte Breccia. Fluids predominantly came from the Tertiary and the Upper Triassic sandstone formation. In the basal layer, Tertiary clays were subjected to intense, ductile deformation, indicating saturation with water. This suggests that water was mixed into the matrix, creating a fluidized basal layer with a strong shear localization. In the upper units, Upper Triassic sandstones are intensely deformed by granular flow. The texture requires that the rocks were disaggregated into granular sand. Vaporization of pore water probably aided fragmentation of these rocks. In the Otting core, hot suevite (T > 600 °C) covered the Bunte Breccia shortly after its emplacement. Vertically oriented gas escape pipes in suevite partly emanate directly at the contact to the Bunte Breccia. They indicate that the Bunte Breccia contained a substantial amount of water in the upper part that was vaporized and escaped through these vents.

A Series of F-Element Chelators; Diaza Crown Ethers Functionalized with Catecholate Binding Substituents

DOE PAGES

Stein, Benjamin W.; Cary, Samantha K.; Berg, John M.; ...

2017-12-06

Here, we report on the preparation of azacrown ethers functionalized with catechol groups. The synthetic approach was (1st) novel in that it made use of the Mannich reaction and (2nd) valuable in that it provided an improved synthesis (in terms of practical deployment) of the known N,N'-bis(2,3-dihydroxybenzyl)-4,13-diaza-18-crown-6, H 4ChaCha. Moreover, it demonstrated potential application of the synthetic method for accommodating a wide range of catecholate functionalities by using the synthetic strategy to prepare N,N'-bis(2,3-dihydroxy-5-tert-butylbenzyl)-4,13-diaza-18-crown-6 (H 4 tBu 2ChaCha) for the first time. These H 4ChaCha and H 4 tBu2ChaCha macrocycles offer exciting opportunity to expand redox chemistry for the f-elements.more » As “proof-of-principle,” we isolated the unusual tetrameric cluster [La 2( tBuChaCha) 2] 2 from reactions between H 4 tBu 2ChaCha and La[N(SiMe 3) 2] 3. Characterization of [La 2( tBuChaCha) 2] 2 by elemental analysis, single crystal X-ray diffraction, IR, and UV–vis–NIR spectroscopy suggested that the complex represented a rare example of an f-element semiquinone. It further demonstrated that the combination of La 3+ and H 4 tBu 2ChaCha provided access to one-electron oxidation chemistry within redox potential windows that were amenable to mild reaction conditions.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weydert, M.; Brennan, J.G.; Andersen, R.A.

Reaction of (MeC{sub 5}H{sub 4}){sub 3}UX (X = Cl, MeC{sub 5}H{sub 4}) with t-BuLi affords the tertiary alkyl complex (MeC{sub 5}H{sub 4}){sub 3}U(t-Bu). Despite uranium(IV) generally being the preferred oxidation state in organometallic systems, (MeC{sub 5}H{sub 4}){sub 3}U(t-Bu) reacts with Lewis bases (L = PMe{sub 3}, THF, RCN, RNC) to yield the reduced uranium(III) base adducts (MeC{sub 5}H{sub 4}){sub 3}U(L). Carbon monoxide undergoes migratory insertion into the metal tertiary alkyl bond. The resulting acyl derivative decomposes at 90{degree}C to yield insoluble uranium-containing products and a mixture of tert-butyltoluenes by ring expansion of a methylcyclopentadienyl ligand. Ethylene also undergoes migratory insertionmore » into the metal tertiary alkyl bond. No subsequent insertion of ethylene into the metal carbon bond takes place after the first equivalent has inserted. In marked contrast, reaction of various (MeC{sub 5}H{sub 4}){sub 3}ThX (X = Cl, I, MeC{sub 5}H{sub 4}, O-2,6-Me{sub 2}C{sub 6}H{sub 3}, OTs) compounds with t-BuLi gave intractable materials. However, reaction of the cationic species [(RC{sub 5}H{sub 4}){sub 3}Th](BPh{sub 4}) (R = Me{sub 3}Si, t-Bu) with t-BuLi yields the new thorium hydrides (RC{sub 5}H{sub 4}){sub 3}ThH. 40 refs., 2 figs.« less

A Series of F-Element Chelators; Diaza Crown Ethers Functionalized with Catecholate Binding Substituents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stein, Benjamin W.; Cary, Samantha K.; Berg, John M.

Here, we report on the preparation of azacrown ethers functionalized with catechol groups. The synthetic approach was (1st) novel in that it made use of the Mannich reaction and (2nd) valuable in that it provided an improved synthesis (in terms of practical deployment) of the known N,N'-bis(2,3-dihydroxybenzyl)-4,13-diaza-18-crown-6, H 4ChaCha. Moreover, it demonstrated potential application of the synthetic method for accommodating a wide range of catecholate functionalities by using the synthetic strategy to prepare N,N'-bis(2,3-dihydroxy-5-tert-butylbenzyl)-4,13-diaza-18-crown-6 (H 4 tBu 2ChaCha) for the first time. These H 4ChaCha and H 4 tBu2ChaCha macrocycles offer exciting opportunity to expand redox chemistry for the f-elements.more » As “proof-of-principle,” we isolated the unusual tetrameric cluster [La 2( tBuChaCha) 2] 2 from reactions between H 4 tBu 2ChaCha and La[N(SiMe 3) 2] 3. Characterization of [La 2( tBuChaCha) 2] 2 by elemental analysis, single crystal X-ray diffraction, IR, and UV–vis–NIR spectroscopy suggested that the complex represented a rare example of an f-element semiquinone. It further demonstrated that the combination of La 3+ and H 4 tBu 2ChaCha provided access to one-electron oxidation chemistry within redox potential windows that were amenable to mild reaction conditions.« less

Differences between male and female rhesus monkey erythrocyte acetylcholinesterase and plasma cholinesterase activity before and after exposure to sarin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woodard, C.L.; Calamaio, C.A.; Kaminskis, A.

The female rhesus monkey has a menstrual cycle like the human. Additionally, several differences in enzyme levels between males and females and in the female during the menstrual cycle are present. Therefore we quantitated plasma cholinesterase (ChE/BuChE) and erythrocyte (RBC) acetylcholinesterase (AChE) activity before and after exposure to sarin (GB)(1 5 ug/kg, iv; a 0.75 LD50), in male and female rhesus (Macaca mulatta) monkeys. Twenty-eight-day preexposure baseline plasma ChE and RBC AChE values for six male and six female rhesus monkeys were compared for intra-animal, within sex and between sex differences. After these baseline values were obtained, the organophosphorus (OP)more » compound/Isopropyl methylphosphono-fluoridate (GB) was administered to atropinized monkeys to determine if there was a significant in vivo difference between the sexes in their response to this intoxication in regard to the rate of BuChE /AChE inhibition, pyridine-2-aldoxime methyl chloride (2-PAM) reactivation of the phosphonylated BuChE and the rate of aging of the phosphonylated:BuChE/AChE. In the pre-exposure portion of the protocol; the intra-animal and intra-group BuChE/AChE variations were found to be minimal; but there were significant differences between the male and female monkeys in both plasma BuChE and RBC AChE levels; although probably clinically insignificant in respect to an OP intoxication. No significant cyclic fluctuations were seen during the 28-day study in either sex.« less

The mechanism of hypoglycemic action of the semi-purified fractions of Averrhoa bilimbi in streptozotocin-diabetic rats.

PubMed

Pushparaj, P N; Tan, B K; Tan, C H

2001-12-21

In the present study, we have examined the possible mechanism of the hypoglycemic action of the semi-purified fractions of an ethanolic extract of Averrhoa bilimbi Linn (Oxalidaceae) leaves (ABe) in streptozotocin-diabetic male Sprague-Dawley (SD) rats. The ABe was partitioned with water and butanol to yield a butanol-soluble fraction (BuF) and a water-soluble fraction (AF). The AF was further partitioned with ethyl acetate and hexane to obtain ethyl acetate (EF) and hexane (HF) soluble fractions. The hypoglycemic property of each fraction was assessed by the oral glucose tolerance test (OGTT) at a dose of 125-mg/kg-body weight in streptozotocin (STZ)-diabetic rats (STZ 60 mg/kg i.p.). Fractions AF, BuF and the reference drug metformin (500 mg/kg body weight), produced significant blood glucose-lowering effect in the diabetic rats when compared to the vehicle (distilled water). In the long-term study, the diabetic rats were randomly divided into 4 groups and treated orally by gavage with vehicle, AF (125 mg/kg body weight), BuF (125 mg/kg body weight), and metformin (500 mg/kg body weight) respectively twice a day for 14 days. On day 7 and day 14, AF and BuF, like the reference drug, metformin, lowered the fasting blood glucose concentration significantly (P < 0.05) when compared with the vehicle. The serum insulin level was significantly increased in the AF-treated rats only on day 14 when compared to that in the vehicle-treated rats on day zero (P < 0.05). The serum insulin level in BuF-treated rats was also significantly higher (P < 0.05) on both day 7 and day 14 compared to that on day zero. Hepatic glucose-6-phosphatase activity was significantly lower (P<0.05) in AF- and metformin-treated groups, but not in BuF-treated groups, compared to that in vehicle-treated group. However, there was no change in hepatic glycogen content in AF-, BuF- and metformin-treated group compared to the vehicle-treated group. These results indicate that AF is more potent than BuF in the amelioration of hyperglycemia in STZ-diabetic rats and is a potential source for the isolation of new orally active agent(s) for anti-diabetic therapy.

Clinical Epidemiology of Buruli Ulcer from Benin (2005-2013): Effect of Time-Delay to Diagnosis on Clinical Forms and Severe Phenotypes.

PubMed

Capela, Carlos; Sopoh, Ghislain E; Houezo, Jean G; Fiodessihoué, René; Dossou, Ange D; Costa, Patrício; Fraga, Alexandra G; Menino, João F; Silva-Gomes, Rita; Ouendo, Edgard M; Rodrigues, Fernando; Pedrosa, Jorge

2015-01-01

Buruli Ulcer (BU) is a neglected infectious disease caused by Mycobacterium ulcerans that is responsible for severe necrotizing cutaneous lesions that may be associated with bone involvement. Clinical presentations of BU lesions are classically classified as papules, nodules, plaques and edematous infiltration, ulcer or osteomyelitis. Within these different clinical forms, lesions can be further classified as severe forms based on focality (multiple lesions), lesions' size (>15 cm diameter) or WHO Category (WHO Category 3 lesions). There are studies reporting an association between delay in seeking medical care and the development of ulcerative forms of BU or osteomyelitis, but the effect of time-delay on the emergence of lesions classified as severe has not been addressed. To address both issues, and in a cohort of laboratory-confirmed BU cases, 476 patients from a medical center in Allada, Benin, were studied. In this laboratory-confirmed cohort, we validated previous observations, demonstrating that time-delay is statistically related to the clinical form of BU. Indeed, for non-ulcerated forms (nodule, edema, and plaque) the median time-delay was 32.5 days (IQR 30.0-67.5), while for ulcerated forms it was 60 days (IQR 20.0-120.0) (p = 0.009), and for bone lesions, 365 days (IQR 228.0-548.0). On the other hand, we show here that time-delay is not associated with the more severe phenotypes of BU, such as multi-focal lesions (median 90 days; IQR 56-217.5; p = 0.09), larger lesions (diameter >15 cm) (median 60 days; IQR 30-120; p = 0.92) or category 3 WHO classification (median 60 days; IQR 30-150; p = 0.20), when compared with unifocal (median 60 days; IQR 30-90), small lesions (diameter ≤15 cm) (median 60 days; IQR 30-90), or WHO category 1+2 lesions (median 60 days; IQR 30-90), respectively. Our results demonstrate that after an initial period of progression towards ulceration or bone involvement, BU lesions become stable regarding size and focal/multi-focal progression. Therefore, in future studies on BU epidemiology, severe clinical forms should be systematically considered as distinct phenotypes of the same disease and thus subjected to specific risk factor investigation.

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Science.gov Websites

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Solid State Synthesis Under Supramolecular Control of a 2D Heterotetratopic Self-complementary Tecton Tailored to Halogen Bonding

DTIC Science & Technology

2006-07-31

BuLi . A 96 : 4 mixture of trans : cis isomers was obtained in 84% overall yield; stereoisomers were easily separated by chroma- tography. Iodination of...the tetrafluorobenzene group12 was carried out with n- BuLi –I2 in THF affording 4 in 85% yield (Scheme 1). Orange-yellow prismatic crystals have been...mmol) of phosphonium salt 1 were suspended in 1 mL of THF at 70 1C. 0.7 mmol of n- BuLi (1.6 M) were added and the mixture was warmed up to room

Electrochemical Oxidation of Alkylnitro Compounds PP-1345

DTIC Science & Technology

2004-08-17

to the solution, to deprotonate the methyl group. Figure 22 shows the voltammetric response recorded in a CH3OH /0.2 M Bu4NBF4 solution containing...Voltammogram of Glassy Carbon (GC) Electrode 50 mM TNT/ CH3OH /0.2 M Bu4NBF4/55 mM NaOH 15 The standard redox potential for this reaction was... reaction ). Addition of 100 mM TNT to the basic solution ( CH3OH /0.2 M Bu4NBF4/ 55 mM NaOH) resulted in the appearance of a new oxidation wave with a

Reversible Inter- and Intramolecular Carbon-Hydrogen Activation, Hydrogen Addition, and Catalysis by the Unsaturated Complex Pt(IPr)(SnBu(t)3)(H).

PubMed

Koppaka, Anjaneyulu; Captain, Burjor

2016-03-21

The complex Pt(IPr)(SnBu(t)3)(H) (1) was obtained from the reaction of Pt(COD)2 with Bu(t)3SnH and IPr [IPr = N,N'-bis(2,6-diisopropylphenyl)imidazol-2-ylidene]. Complex 1 undergoes exchange reactions with deuterated solvents (C6D6, toluene-d8, and CD2Cl2), where the hydride ligand and the methyl hydrogen atoms on the isopropyl group of the IPr ligand have been replaced by deuterium atoms. Complex 1 reacts with H2 gas reversibly at room temperature to yield the complex Pt(IPr)(SnBu(t)3)(H)3 (2). Complex 2 also undergoes exchange reactions with deuterated solvents as in 1 to deuterate the hydride ligands and the methyl hydrogen atoms on the isopropyl group of the IPr ligand. Complex 1 catalyzes the hydrogenation of styrene to ethylbenzene at room temperature. The reaction of 1 with 1 equiv of styrene at -20 °C yields the η(2)-coordinated product Pt(IPr)(SnBu(t)3)(η(2)-CH2CHPh)(H) (3), and with 2 equiv of styrene, it forms Pt(IPr)(η(2)-CH2CHPh)2 (4).

The contribution of community health workers to the control of Buruli ulcer in the Ngoantet area, Cameroon.

PubMed

Vouking, Marius Zambou; Takougang, Innocent; Mbam, Léonard Mbam; Mbuagbaw, Lawrence; Tadenfok, Carine Nouboudem; Tamo, Claire Violette

2013-01-01

Buruli ulcer (BU) is a skin disease caused by Mycobacterium ulcerans. It is the third most common mycobacterial infection after tuberculosis and leprosy. Community Health Workers (CHWs) hold the potential to support patients and their families at the community level. We conducted a cross-sectional descriptive study to assess the participation of CHWs in the early diagnosis and treatment of BU in Ngoantet, Cameroon. The CHWs performance was measured using: the number of cases referred to the Ngoantet Health Centre, the percentage of accomplished referrals, the percentage of cases referred by CHWs confirmed by the staff of Ngoantet Health Centre. Data was analyzed using Epi-info version 3.4.1. and Microsoft Office Excel 2003. The study focused on 51 CHWs in the Ngoantet health area. The referral rate was 95.0%. Most of the suspicious cases (91.5%) referred were confirmed by health workers. Most CHWs (78.4%) declared that they had identified at least one presumptive case of BU infection. We conclude that the CHWs can play a key role in scaling up BU control activities using a referral system. This study confirms the role of home visits and inspections in the early detection and treatment of BU.

Effect of balanced low pressure drying of curcuma longa leaf on skin immune activation activities.

PubMed

Choi, Wooseok; Lim, Hye Won; Lee, Hyeon Yong

2014-01-01

The effect of balanced low pressure drying pretreatment associated with ultrasonication extraction (BU) on the enhancement of skin immune modulatory activities of Curcuma longa leaf was studied by comparing with conventional hot air drying (HE), freeze drying (FE) and balanced low pressure drying (BE) pretreatment processes. In considering skin immune activation activities such as the inhibition of hyaluronidase activity, the BU extract showed ca. 10% higher than those of HE, and even higher than that of the FE extract. Nitric oxide production from macrophage of the BU extract in adding 1.0 mg/mL was increased up to 16.5 μM. When measuring inhibition of IL-6 and TNF-a production from the human T lymphocytes (T cell), the BU extract also showed 53% and 78% of inhibition effect, respectively. It is found that the BU extract could effectively suppress the expression levels of skin inflammation related genes such as Cox-2 and iNOS, down to 80% and 85% compared to the control, respectively. Balanced low pressure drying process was especially active on dehydration of the leaves with minimizing the destruction and making easier elution of the bioactive substances, which resulted in higher extraction yield and better biological activities.

Transition state analogs of 5'-methylthioadenosine nucleosidase disrupt quorum sensing.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gutierrez, J.; Crowder, T; Rinaldo-Matthis, A

2009-01-01

5'-Methylthioadenosine/S-adenosylhomocysteine nucleosidase (MTAN) is a bacterial enzyme involved in S-adenosylmethionine-related quorum sensing pathways that induce bacterial pathogenesis factors. Transition state analogs MT-DADMe-Immucillin-A, EtT-DADMe-Immucillin-A and BuT-DADMe-Immucillin-A are slow-onset, tight-binding inhibitors of Vibrio cholerae MTAN (VcMTAN), with equilibrium dissociation constants of 73, 70 and 208 pM, respectively. Structural analysis of VcMTAN with BuT-DADMe-Immucillin-A revealed interactions contributing to the high affinity. We found that in V. cholerae cells, these compounds are potent MTAN inhibitors with IC50 values of 27, 31 and 6 nM for MT-, EtT- and BuT-DADMe-Immucillin-A, respectively; the compounds disrupt autoinducer production in a dose-dependent manner without affecting growth. MT- andmore » BuT-DADMe-Immucillin-A also inhibited autoinducer-2 production in enterohemorrhagic Escherichia coli O157:H7 with IC{sub 50} values of 600 and 125 nM, respectively. BuT-DADMe-Immucillin-A inhibition of autoinducer-2 production in both strains persisted for several generations and caused reduction in biofilm formation. These results support MTAN's role in quorum sensing and its potential as a target for bacterial anti-infective drug design.« less

A density management diagram for even-aged ponderosa pine stands

Treesearch

James N. Long; John D. Shaw

2005-01-01

We developed a density management diagram (DMD) for ponderosa pine using Forest Inventory and Analysis (FIA) data. Analysis plots were drawn from all FIA plots in the western United States on which ponderosa pine occurred. A total of 766 plots met the criteria for analysis. Selection criteria were for purity, defined as ponderosa pine basal area 80% of plot basal area...

Effects of Pine and Hardwood Basal Areas After Uneven-Aged Silvicultural Treatments on Wildlife Habitat

Treesearch

Darren A. Miller; Bruce D. Leopold; L. Mike Conner; Michael G. Shelton

1999-01-01

Uneven-aged management (UEAM) is becoming increasingly popular in the southeastern United States. However, effects of UEAM on wildlife habitat have not been adequately documented. We examined response of habitat within stands of varying levels of pine and hardwood basal area under an uneven-aged managegement regime in southern Mississippi. Summer and winter trends in...

Forage production after thinning a natural loblolly pine-hardwoocl stand to clifferent basal areas

Treesearch

David G. Peitz; Michael G. Shelton; Philip A. Tappe

2001-01-01

Mixed pine (Pinus spp.)-hardwood forests are common in the southern United States (U.S.), but little quantitative information exists on the response of understory forage to reductions in basal area from thinning. We determined understory forage characteristics before thinning and 2 and 4 years after thinning a 35-year-old natural loblolly pine (

[Access to primary healthcare services: still a way to go].

PubMed

Mendes, Antônio da Cruz Gouveia; Miranda, Gabriella Morais Duarte; Figueiredo, Karla Erika Gouveia; Duarte, Petra Oliveira; Furtado, Betise Mery Alencar Sousa Macau

2012-11-01

This study seeks to evaluate accessibility to the Basic Units of the Family Health Strategy (ESF-UB) and Traditional Basic Units (BU-T) in the city of Recife in 2009. Data were collected through three instruments: a roadmap for systematic observation of the units and questionnaires for users and professional units. This is a descriptive cross-sectional study using a quantitative approach, and 1180 users, 61 doctors and 56 nurses were interviewed. The results showed good ties and recognition of users whereby primary healthcare is seen as the access portal to the health system. In the comparison between ESF-UB and UB-T, evaluations are always more favorable to the family healthcare strategy, though with relatively insignificant differences. The overall result revealed widespread dissatisfaction with the difficulty of obtaining drugs and taking tests, and also with the waiting times and access to specialized care. This showed the existence of organizational problems that may constitute barriers limiting accessibility to basic healthcare services for users.

7 CFR 1412.52 - Direct payment provisions.

Code of Federal Regulations, 2010 CFR

2010-01-01

...) Oats—$0.024/bu. (6) Upland cotton—$0.0667/lb. (7) Long grain rice—$2.35/cwt. (8) Medium grain rice—$2.35/cwt. (9) Soybeans—$0.44/bu. (10) Other oilseeds—$0.80/cwt. (11) Peanuts—$36.00/ton. (e) For 2008...

7 CFR 1412.52 - Direct payment provisions.

Code of Federal Regulations, 2013 CFR

2013-01-01

...) Oats—$0.024/bu. (6) Upland cotton—$0.0667/lb. (7) Long grain rice—$2.35/cwt. (8) Medium grain rice—$2.35/cwt. (9) Soybeans—$0.44/bu. (10) Other oilseeds—$0.80/cwt. (11) Peanuts—$36.00/ton. (e) For 2008...

7 CFR 1412.52 - Direct payment provisions.

Code of Federal Regulations, 2011 CFR

2011-01-01

...) Oats—$0.024/bu. (6) Upland cotton—$0.0667/lb. (7) Long grain rice—$2.35/cwt. (8) Medium grain rice—$2.35/cwt. (9) Soybeans—$0.44/bu. (10) Other oilseeds—$0.80/cwt. (11) Peanuts—$36.00/ton. (e) For 2008...

7 CFR 1412.52 - Direct payment provisions.

Code of Federal Regulations, 2014 CFR

2014-01-01

...) Oats—$0.024/bu. (6) Upland cotton—$0.0667/lb. (7) Long grain rice—$2.35/cwt. (8) Medium grain rice—$2.35/cwt. (9) Soybeans—$0.44/bu. (10) Other oilseeds—$0.80/cwt. (11) Peanuts—$36.00/ton. (e) For 2008...

7 CFR 1412.52 - Direct payment provisions.

Code of Federal Regulations, 2012 CFR

2012-01-01

...) Oats—$0.024/bu. (6) Upland cotton—$0.0667/lb. (7) Long grain rice—$2.35/cwt. (8) Medium grain rice—$2.35/cwt. (9) Soybeans—$0.44/bu. (10) Other oilseeds—$0.80/cwt. (11) Peanuts—$36.00/ton. (e) For 2008...

Unexpected Reactivity of [(η(5) -1,2,4-tBu3 C5 H2 )Ni(η(3) -P3 )] towards Main Group Nucleophiles and by Reduction.

PubMed

Mädl, Eric; Balázs, Gábor; Peresypkina, Eugenia V; Scheer, Manfred

2016-06-27

The reduction of [Cp'''Ni(η(3) -P3 )] (1; Cp'''=η(5) -1,2,4-tBu3 C5 H2 ) with potassium produces the complex anion [(Cp'''Ni)2 (μ,η(2:2) -P8 )](2-) (2), which contains a realgar-like P8 unit. The anionic triple-decker sandwich complex [(Cp'''Ni)2 (μ,η(3:3) -P3 )](-) (3) with a cyclo-P3 middle deck is obtained when 1 is treated with NaNH2 as a nucleophile. Na[3] can subsequently be oxidized with AgOTf to the neutral triple-decker complex [(Cp'''Ni)2 (μ,η(3:3) -P3 )] (4). In contrast, 1 reacts with LiPPh2 to give the anionic compound [(Cp'''Ni)2 (μ,η(2:2) -P6 PPh2 )](-) (5), a complex containing a bicyclic P7 fragment capped by two Cp'''Ni units. Protonation of Li[5] with HBF4 leads to the neutral complex [(Cp'''Ni)2 (μ,η(2:2) -(HP6 PPh2 )] (6). Adding LiNMe2 to 1 results in [Cp'''Ni(η(2) -P3 NMe2 )](-) (7) becoming accessible, a complex which forms as a result of nucleophilic attack at the cyclo-P3 ring of 1. The complexes K2 [2], Na[3], 4, 6, and Li[7] were fully characterized and their structures determined by single-crystal X-ray diffraction. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effects of copper and butyltin compounds on the growth, photosynthetic activity and toxin production of two HAB dinoflagellates: The planktonic Alexandrium catenella and the benthic Ostreopsis cf. ovata.

PubMed

Couet, Douglas; Pringault, Olivier; Bancon-Montigny, Chrystelle; Briant, Nicolas; Elbaz Poulichet, Françoise; Delpoux, Sophie; Kefi-Daly Yahia, Ons; Hela, BenGharbia; Charaf, M'Rabet; Hervé, Fabienne; Rovillon, Georges; Amzil, Zouher; Laabir, Mohamed

2018-03-01

Controlled laboratory experiments were conducted to test the effects of copper (Cu 2+ ) and butyltins (BuT) on the growth, photosynthetic activity and toxin content of two HABs (Harmful Algal Blooms) dinoflagellates, the planktonic Alexandrium catenella and the benthic Ostreopsis cf. ovata. Microalgae were exposed to increasing concentrations of Cu 2+ (10 -4 to 31 nM) or BuT (0.084 to 84 nM) for seven days. When considering the growth, EC 50 values were 0.16 (±0.09) nM and 0.03 (±0.02) nM of Cu 2+ for A. catenella and O. cf. ovata, respectively. Regarding BuT, EC 50 was 14.2 (±6) nM for O. cf. ovata, while A. catenella growth inhibition appeared at BuT concentrations ≥27 nM. Photosynthetic activity of the studied dinoflagellates decreased with increasing Cu and BuT concentrations. For O. cf. ovata, the response of this physiological parameter to contamination was less sensitive than the biomass. Cu exposure induced the formation of temporary cysts in both organisms that could resist adverse conditions. The ovatoxin-a and -b concentrations in O. cf. ovata cells increased significantly in the presence of Cu. Altogether, the results suggest a better tolerance of the planktonic A. catenella to Cu and BuT. This could result in a differentiated selection pressure exerted by these metals on phytoplankton species in highly polluted waters. The over-production of toxins in response to Cu stress could pose supplementary health and socio-economic threats in the contaminated marine ecosystems where HABs develop. Copyright © 2018 Elsevier B.V. All rights reserved.

Biochemical and oxidative stress markers in the liver and kidneys of rats submitted to different protocols of anabolic steroids.

PubMed

Dornelles, Guilherme Lopes; Bueno, Andressa; de Oliveira, Juliana Sorraila; da Silva, Aleksandro Schafer; França, Raqueli Teresinha; da Silva, Cássia Bagolin; Machado, Márcia Silveira Netto; Petry, Letícia do Santos; Abdalla, Fátima Husein; Lhamas, Cibele Lima; de Andrade, Cinthia Melazzo

2017-01-01

The objective of this study was to evaluate the effects of different protocols (P1, P2, and P3) of boldenone undecylenate (BU) and stanozolol (ST) on markers of liver and kidney function and variables of oxidative stress in these organs. For this, 54 male Wistar rats were divided into nine groups of six animals each. Each animal received intramuscularly 5.0 mg kg -1 of BU or ST once a week for 4 weeks (P1); 2.5 mg kg -1 of BU or ST once a week for 8 weeks (P2); and 1.25 mg kg -1 of BU or ST once a week for 12 weeks (P3). For each protocol, a control group was used, and they received 0.1 ml of olive oil intramuscularly. Blood and fragments of liver and kidney were collected for alanine aminotransferase activity (ALT), alkaline phosphatase, albumin, creatinine, cholesterol, total protein, triglycerides, urea, reactive oxygen species, thiobarbituric acid reactive substances, total thiols, and glutathione evaluation. The results show that the BU in doses of 5 (day 30) and 2.5 mg kg -1 (day 60) changes the ALT seric activity, possibly showing a hepatotoxic effect. High doses of BU may lead to increased levels of cholesterol (protocol P1) possibly due to inhibition of the normal steroid biosynthesis process. All protocols used caused changes in the redox balance of the organs studied (except in the liver, protocol P2), which indicates that these drugs might be harmful even at low doses.

Metformin and Its Sulfenamide Prodrugs Inhibit Human Cholinesterase Activity.

PubMed

Markowicz-Piasecka, Magdalena; Sikora, Joanna; Mateusiak, Łukasz; Mikiciuk-Olasik, Elżbieta; Huttunen, Kristiina M

2017-01-01

The results of epidemiological and pathophysiological studies suggest that type 2 diabetes mellitus (T2DM) may predispose to Alzheimer's disease (AD). The two conditions present similar glucose levels, insulin resistance, and biochemical etiologies such as inflammation and oxidative stress. The diabetic state also contributes to increased acetylcholinesterase (AChE) activity, which is one of the factors leading to neurodegeneration in AD. The aim of this study was to assess in vitro the effects of metformin, phenformin, and metformin sulfenamide prodrugs on the activity of human AChE and butyrylcholinesterase (BuChE) and establish the type of inhibition. Metformin inhibited 50% of the AChE activity at micromolar concentrations (2.35  μ mol/mL, mixed type of inhibition) and seemed to be selective towards AChE since it presented low anti-BuChE activity. The tested metformin prodrugs inhibited cholinesterases (ChE) at nanomolar range and thus were more active than metformin or phenformin. The cyclohexyl sulfenamide prodrug demonstrated the highest activity towards both AChE (IC 50  = 890 nmol/mL, noncompetitive inhibition) and BuChE (IC 50  = 28 nmol/mL, mixed type inhibition), while the octyl sulfenamide prodrug did not present anti-AChE activity, but exhibited mixed inhibition towards BuChE (IC 50  = 184 nmol/mL). Therefore, these two bulkier prodrugs were concluded to be the most selective compounds for BuChE over AChE. In conclusion, it was demonstrated that biguanides present a novel class of inhibitors for AChE and BuChE and encourages further studies of these compounds for developing both selective and nonselective inhibitors of ChEs in the future.

Dianionic Titanyl and Vanadyl (Cation+ )2 [MIV O(Pc4- )]2- Phthalocyanine Salts Containing Pc4- Macrocycles.

PubMed

Konarev, Dmitri V; Kuzmin, Alexey V; Khasanov, Salavat S; Litvinov, Alexey L; Otsuka, Akihiro; Yamochi, Hideki; Kitagawa, Hiroshi; Lyubovskaya, Rimma N

2018-06-18

In this study, the titanyl and vanadyl phthalocyanine (Pc) salts (Bu 4 N + ) 2 [M IV O(Pc 4- )] 2- (M=Ti, V) and (Bu 3 MeP + ) 2 [M IV O(Pc 4- )] 2- (M=Ti, V) with [M IV O(Pc 4- )] 2- dianions were synthesized and characterized. Reduction of M IV O(Pc 2- ) carried out with an excess of sodium fluorenone ketyl in the presence of Bu 4 N + or Bu 3 MeP + is exclusive to the phthalocyanine centers, forming Pc 4- species. During reduction, the metal +4 charge did not change, implying that Pc is an non-innocent ligand. The Pc negative charge increase caused the C-N(pyr) bonds to elongate and the C-N(imine) bonds to alternate, thus increasing the distortion of Pc. Jahn-Teller effects are significant in the [eg(π*)] 2 dianion ground state and can additionally distort the Pc macrocycles. Blueshifts of the Soret and Q-bands were observed in the UV/Vis/NIR when M IV O(Pc 2- ) was reduced to [M IV O(Pc . 3- )] . - and [M IV O(Pc 4- )] 2- . From magnetic measurements, [Ti IV O(Pc 4- )] 2- was found to be diamagnetic and (Bu 4 N + ) 2 [V IV O(Pc 4- )] 2- and (Bu 3 MeP + ) 2 [V IV O(Pc 4- )] 2- were found to have magnetic moments of 1.72-1.78 μ B corresponding to an S=1/2 spin state owing to V IV electron spin. As a result, two latter salts show EPR signals with V IV hyperfine coupling. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Homoleptic diphosphacyclobutadiene complexes [M(η(4)-P2C2R2)2]x- (M = Fe, Co; x = 0, 1).

PubMed

Wolf, Robert; Ehlers, Andreas W; Khusniyarov, Marat M; Hartl, František; de Bruin, Bas; Long, Gary J; Grandjean, Fernande; Schappacher, Falko M; Pöttgen, Rainer; Slootweg, J Chris; Lutz, Martin; Spek, Anthony L; Lammertsma, Koop

2010-12-27

The preparation and comprehensive characterization of a series of homoleptic sandwich complexes containing diphosphacyclobutadiene ligands are reported. Compounds [K([18]crown-6)(thf)(2)][Fe(η(4)-P(2)C(2)tBu(2))(2)] (K1), [K([18]crown-6)(thf)(2)][Co(η(4)-P(2)C(2)tBu(2))(2)] (K2), and [K([18]crown-6)(thf)(2)][Co(η(4)-P(2)C(2)Ad(2))(2)] (K3, Ad = adamantyl) were obtained from reactions of [K([18]crown-6)(thf)(2)][M(η(4)-C(14)H(10))(2)] (M = Fe, Co) with tBuC[triple bond]P (1, 2), or with AdC[triple bond]P (3). Neutral sandwiches [M(η(4)-P(2)C(2)tBu(2))(2)] (4: M = Fe 5: M = Co) were obtained by oxidizing 1 and 2 with [Cp(2)Fe]PF(6). Cyclic voltammetry and spectro-electrochemistry indicate that the two [M(η(4)-P(2)C(2)tBu(2))(2)](-)/[M(η(4)-P(2)C(2)tBu(2))(2)] moieties can be reversibly interconverted by one electron oxidation and reduction, respectively. Complexes 1-5 were characterized by multinuclear NMR, EPR (1 and 5), UV/Vis, and Mössbauer spectroscopies (1 and 4), mass spectrometry (4 and 5), and microanalysis (1-3). The molecular structures of 1-5 were determined by using X-ray crystallography. Essentially D(2d)-symmetric structures were found for all five complexes, which show the two 1,3-diphosphacyclobutadiene rings in a staggered orientation. Density functional theory calculations revealed the importance of covalent metal-ligand π bonding in 1-5. Possible oxidation state assignments for the metal ions are discussed.

Morphine-induced antinociception in the rat: supra-additive interactions with imidazoline I₂ receptor ligands.

PubMed

Li, Jun-Xu; Zhang, Yanan; Winter, Jerrold C

2011-11-01

Pain remains a significant clinical challenge and currently available analgesics are not adequate to meet clinical needs. Emerging evidence suggests the role of imidazoline I(2) receptors in pain modulation primarily from studies of the non-selective imidazoline receptor ligand, agmatine. However, little is known of the generality of the effect to selective I(2) receptor ligands. This study examined the antinociceptive effects of two selective I(2) receptor ligands 2-BFI and BU224 (>2000-fold selectivity for I(2) receptors over α(2) adrenoceptors) in a hypertonic (5%) saline-induced writhing test and analyzed their interaction with morphine using a dose-addition analysis. Morphine, 2-BFI and BU224 but not agmatine produced a dose-dependent antinociceptive effect. Both composite additive curve analyses and isobolographical plots revealed a supra-additive interaction between morphine and 2-BFI or BU224, whereas the interaction between 2-BFI and BU224 was additive. The antinociceptive effect of 2-BFI and BU224 was attenuated by the I(2) receptor antagonist/α(2) adrenoceptor antagonist idazoxan but not by the selective α(2) adrenoceptor antagonist yohimbine, suggesting an I(2) receptor-mediated mechanism. Agmatine enhanced the antinociceptive effect of morphine, 2-BFI and BU224 and the enhancement was prevented by yohimbine, suggesting that the effect was mediated by α(2) adrenoceptors. Taken together, these data represent the first report that selective I(2) receptor ligands have substantial antinociceptive activity and produce antinociceptive synergy with opioids in a rat model of acute pain. These data suggest that drugs acting on imidazoline I(2) receptors may be useful either alone or in combination with opioids for the treatment of pain. Copyright © 2011 Elsevier B.V. All rights reserved.

Silica-supported, single-site titanium catalysts for olefin epoxidation. A molecular precursor strategy for control of catalyst structure.

PubMed

Jarupatrakorn, Jonggol; Don Tilley, T

2002-07-17

A molecular precursor approach involving simple grafting procedures was used to produce site-isolated titanium-supported epoxidation catalysts of high activity and selectivity. The tris(tert-butoxy)siloxy titanium complexes Ti[OSi(O(t)Bu)(3)](4) (TiSi4), ((i)PrO)Ti[OSi(O(t)Bu)(3)](3) (TiSi3), and ((t)BuO)(3)TiOSi(O(t)Bu)(3) (TiSi) react with the hydroxyl groups of amorphous Aerosil, mesoporous MCM-41, and SBA-15 via loss of HO(t)Bu and/or HOSi(O(t)Bu)(3) and introduction of titanium species onto the silica surface. Powder X-ray diffraction, nitrogen adsorption/desorption, infrared, and diffuse reflectance ultraviolet spectroscopies were used to investigate the structures and chemical natures of the surface-bound titanium species. The titanium species exist mainly in isolated, tetrahedral coordination environments. Increasing the number of siloxide ligands in the molecular precursor decreases the amount of titanium that can be introduced this way, but also enhances the catalytic activity and selectivity for the epoxidation of cyclohexene with cumene hydroperoxide as oxidant. In addition, the high surface area mesoporous silicas (MCM-41 and SBA-15) are more effective than amorphous silica as supports for these catalysts. Supporting TiSi3 on the SBA-15 affords highly active cyclohexene epoxidation catalysts (0.25-1.77 wt % Ti loading) that provide turnover frequencies (TOFs) of 500-1500 h(-1) after 1 h (TOFs are reduced by about half after calcination). These results demonstrate that oxygen-rich siloxide complexes of titanium are useful as precursors to supported epoxidation catalysts.

131I-MIBG followed by consolidation with busulfan, melphalan and autologous stem cell transplantation for refractory neuroblastoma.

PubMed

French, Sarah; DuBois, Steven G; Horn, Biljana; Granger, Meaghan; Hawkins, Randall; Pass, Amy; Plummer, Ellen; Matthay, Katherine

2013-05-01

(131) I-metaiodobenzylguanidine (MIBG) produces a 37% response rate in relapsed/refractory neuroblastoma, and could be used to improve remission status prior to myeloablative chemotherapy with autologous stem cell transplant (ASCT). The purpose of our report was to evaluate safety and response with MIBG therapy followed by myeloablative busulfan and melphalan (BuMel) with ASCT in patients with refractory neuroblastoma. Retrospective chart review was done on patients treated with MIBG (18 mCi/kg) on Day 1 and ASCT on day 14. Six to eight weeks after MIBG, patients without progressive disease received IV busulfan on days -6 to -2 (target Css 700-900), melphalan (140 mg/m2 IV) on day -1, and ASCT on Day 0. Response and toxicity were evaluated after MIBG and again after myeloablative therapy. Eight patients completed MIBG/ASCT followed by BuMel/ASCT. MIBG was well tolerated, with grade 3 or 4 non-hematologic toxicity limited to one patient with sepsis. Grade 3 mucositis occurred in six patients after BuMel/ASCT. One patient developed sinusoidal obstructive syndrome (SOS) and died 50 days post-ASCT following myeloablative conditioning. All patients engrafted neutrophils (median 16.5 days) and platelets (median 32 days) after BuMel, excluding the patient with SOS. After all therapy, there were three complete, two partial, and one minor response in seven evaluable patients. MIBG at doses up to 18 mCi/kg can be safely administered 6 weeks prior to a BuMel consolidative regimen for refractory neuroblastoma. Preceding MIBG did not impair engraftment following BuMel. This regimen is being further evaluated in a Children's Oncology Group (COG) trial. Copyright © 2012 Wiley Periodicals, Inc.

Experimental and Theoretical Demonstration on the Transport Properties of Fused Ring Host Materials for Organic Light-Emitting Diodes

NASA Astrophysics Data System (ADS)

Tse, S. C.; So, S. K.; Yeung, M. Y.; Lo, C. F.; Wen, S. W.; Chen, C. H.

2006-01-01

The charge transport properties of three tertiary-butyl (t-Bu) substituted anthracene derivatives (ADN), critical blue host materials for organic light-emitting diodes (OLEDs), have been investigated experimentally and computationally. From time-of-flight (TOF) measurements, all ADN compounds exhibit ambipolar characters. The hole and electron mobilities are in the range (1--5)× 10-7 cm2 V-1 s-1 under an external applied field of about 1 MV cm-1. Un-substituted ADN has the highest carrier mobilities while heavily t-Bu substituted ADN has the least. The electron and hole conducting properties of are consistent with ab initio calculation, which indicates that the frontier orbitals are localized mainly on the anthracene moiety. t-Bu substitutions in ADN increase the hopping path lengths among the molecules and hence reduce the electron and hole mobilities. The results demonstrate that t-Bu substitution is an effective means of engineering the conductivity of organic charge transporter for OLED applications.

Novel structural hybrids of pyrazolobenzothiazines with benzimidazoles as cholinesterase inhibitors.

PubMed

Aslam, Sana; Zaib, Sumera; Ahmad, Matloob; Gardiner, John M; Ahmad, Aqeel; Hameed, Abdul; Furtmann, Norbert; Gütschow, Michael; Bajorath, Jürgen; Iqbal, Jamshed

2014-05-06

Two series of novel pyrazolobenzothiazine-based hybrid compounds were efficiently synthesized starting from saccharin sodium salt. Pyrazolo[4,3-c][1,2]benzothiazine scaffolds were N-arylated by using p-fluorobenzaldehyde, followed by the incorporation of a benzimidazole or similar ring systems by treatment with arylenediamines. These phenylene-connected hybrid compounds were investigated as potential inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Compounds 12d and 12k were the most potent AChE inhibitors with IC50 values of 11 and 13 nM, respectively, while 6j (IC50 = 17 nM) proved to be the most active inhibitor against BuChE with remarkable selectivity for BuChE over AChE. Molecular docking studies were also performed on human AChE and BuChE to suggest possible binding modes in which the inhibitor's extended structure is accommodated along the active site gorge of both enzymes. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Cross-benzoin and Stetter-type reactions mediated by KOtBu-DMF via an electron-transfer process.

PubMed

Ragno, Daniele; Zaghi, Anna; Di Carmine, Graziano; Giovannini, Pier Paolo; Bortolini, Olga; Fogagnolo, Marco; Molinari, Alessandra; Venturini, Alessandro; Massi, Alessandro

2016-10-18

The condensation of aromatic α-diketones (benzils) with aromatic aldehydes (benzoin-type reaction) and chalcones (Stetter-type reaction) in DMF in the presence of catalytic (25 mol%) KOtBu is reported. Both types of umpolung processes proceed with good efficiency and complete chemoselectivity. On the basis of spectroscopic evidence (MS analysis) of plausible intermediates and literature reports, the occurrence of different ionic pathways have been evaluated to elucidate the mechanism of a model cross-benzoin-like reaction along with a radical route initiated by an electron-transfer process to benzil from the carbamoyl anion derived from DMF. This mechanistic investigation has culminated in a different proposal, supported by calculations and a trapping experiment, based on double electron-transfer to benzil with formation of the corresponding enediolate anion as the key reactive intermediate. A mechanistic comparison between the activation modes of benzils in KOtBu-DMF and KOtBu-DMSO systems is also described.

Substitution and Redox Chemistry of [Bu(4)N](2)[Ta(6)Cl(12)(OSO(2)CF(3))(6)].

PubMed

Prokopuk, Nicholas; Kennedy, Vance O.; Stern, Charlotte L.; Shriver, Duward F.

1998-09-21

Two sequential electrochemical reductions occur for the cluster anion [Ta(6)Cl(12)(OSO(2)CF(3))(6)](2)(-) at 0.89 and 0.29 V vs Ag/AgCl, with the generation [Ta(6)Cl(12)(OSO(2)CF(3))(6)](3)(-) and [Ta(6)Cl(12)(OSO(2)CF(3))(6)](4)(-). Chemical reduction of [Ta(6)Cl(12)(OSO(2)CF(3))(6)](2)(-) by ferrocene produces [Ta(6)Cl(12)(OSO(2)CF(3))(6)](3)(-) with the concomitant shift of the nu(SO(2)) stretch from 1002 to 1018 cm(-)(1). Reaction of [Bu(4)N](2)[Ta(6)Cl(12)(OSO(2)CF(3))(6)] (1) with [Bu(4)N]X (X = Cl, Br, I, NCS) occurs by reduction and substitution, yielding [Bu(4)N](3)[Ta(6)Cl(12)X(6)], where the clusters with X = Br, I, and NCS are new. Spectroscopic (IR and UV-vis) evidence indicates that the reduced cluster core {Ta(6)Cl(12)}(2+) is produced in reaction mixtures of 1 with the halide and pseudohalide ions. Concomitant substitution of the triflate ligands of 1 by X(-) occurs and the rates for the overall reduction and substitution increase in the order X(-) = Cl(-) < Br(-) < NCS(-) < I(-) < CN(-). Reduction of 1 with ferrocene followed by addition of [Bu(4)N]O(2)CCH(3) produces the new cluster [Ta(6)Cl(12)(O(2)CCH(3))(6)](3)(-) isolated as the tetrabutylammonium salt. Cyclic voltammetry and UV-vis spectroscopy on the new clusters [Bu(4)N](3)[Ta(6)Cl(12)X(6)] (X = Br, I, NCS, and O(2)CCH(3)) are reported. Crystal data for [Bu(4)N](3)[Ta(6)Cl(12)(NCS)(6)].CH(2)Cl(2): monoclinic, space group, P2(1)/c (No. 14); a = 25.855(6) Å, b = 21.843(6) Å, c = 16.423(3) Å; beta = 100.03(2) degrees; V = 9133(3) Å(3); Z = 4.

Isolatable organophosphorus(III)-tellurium heterocycles.

PubMed

Nordheider, Andreas; Chivers, Tristram; Schön, Oliver; Karaghiosoff, Konstantin; Athukorala Arachchige, Kasun S; Slawin, Alexandra M Z; Woollins, J Derek

2014-01-13

A new structural arrangement Te3 (RP(III) )3 and the first crystal structures of organophosphorus(III)-tellurium heterocycles are presented. The heterocycles can be stabilized and structurally characterized by the appropriate choice of substituents in Tem (P(III) R)n (m=1: n=2, R=OMes* (Mes*=supermesityl or 2,4,6-tri-tert-butylphenyl); n=3, R=adamantyl (Ad); n=4, R=ferrocene (Fc); m=n=3: R=trityl (Trt), Mesor by the installation of a P(V) 2 N2 anchor in RP(III) [TeP(V) (tBuN)(μ-NtBu)]2 (R=Ad, tBu). Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Improving Basal Reading Programs: A Report of the Adoption Guidelines Project at the Center for the Study of Reading. Reading Education Report No. 68.

ERIC Educational Resources Information Center

Dole, Janice A.; And Others

Commercially developed basal reading programs are used in most elementary school classrooms in the United States. Yet often neither the publishers developing these programs nor the members of textbook adoption committees selecting programs are able to take advantage of the best available knowledge about the reading process and reading instruction.…

Prospective evaluation of basal stromal Doppler studies in women with good ovarian reserve and infertility undergoing in vitro fertilization-embryo transfer treatment: patients with polycystic ovary syndrome versus ovulatory patients.

PubMed

Younis, Johnny S; Jadaon, Jimmy E; Haddad, Sami; Izhaki, Ido; Ben-Ami, Moshe

2011-04-01

To gain insight into the ovarian stromal blood flow in women with polycystic ovary syndrome (PCOS) as compared with women with normal ovulation, good ovarian reserve, and infertility and to evaluate the role of stromal flow in these patients to predict clinical pregnancy in an assisted reproductive technologies setting. A prospective observational cohort study. A university-affiliated reproductive medicine unit. Eighteen consecutive patients with PCOS (study) compared with 101 patients with normal ovulation and infertility (control), undergoing their first IVF-ET treatment at our unit. Women with low ovarian reserve were excluded a priori from evaluation. Basal ovarian reserve parameters and stromal flow studies were conducted as routinely performed in our unit, in a natural cycle before starting treatment. None. Basal ovarian endocrine, sonographic, and stromal flow studies were compared between the groups. After completion of treatment, the stromal flow studies were compared between conception and nonconception cycles. Patients' characteristics and basal ovarian reserve, including endocrine and sonographic parameters, were similar between the PCOS and control groups. Only antral follicle count and LH/FSH ratio were higher in the PCOS as compared with the control group, corresponding to 15.11 ± 6.05 versus 9.05 ± 4.77 and 1.14 ± 0.64 versus 0.79 ± 0.37, respectively. Basal stromal flow indices were similar between the PCOS group and the group with normal ovulation and good ovarian reserve. Clinical pregnancy rate per initiated cycle was 50.0% and 39.6% in the PCOS and control groups, respectively, with no significant difference. Flow indices were similar between conception cycles in the PCOS and control groups. As well, the indices did not differ significantly between conception and nonconception cycles within the PCOS and control groups. Basal ovarian stromal blood flow does not differ between women with PCOS and women with normal ovulation, good ovarian reserve, and infertility. Moreover, stromal flow has no predictive value, in these patients, for clinical pregnancy achievement in an IVF-ET setting. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Symmetry and geometry considerations of atom transfer: deoxygenation of (silox)3WNO and R3PO (R = Me, Ph, (t)Bu) by (silox)3M (M = V, NbL (L = PMe3, 4-picoline), Ta; silox = (t)Bu3SiO).

PubMed

Veige, Adam S; Slaughter, LeGrande M; Lobkovsky, Emil B; Wolczanski, Peter T; Matsunaga, Nikita; Decker, Stephen A; Cundari, Thomas R

2003-10-06

Deoxygenations of (silox)(3)WNO (12) and R(3)PO (R = Me, Ph, (t)Bu) by M(silox)(3) (1-M; M = V, NbL (L = PMe(3), 4-picoline), Ta; silox = (t)Bu(3)SiO) reflect the consequences of electronic effects enforced by a limiting steric environment. 1-Ta rapidly deoxygenated R(3)PO (23 degrees C; R = Me (DeltaG degrees (rxn)(calcd) = -47 kcal/mol), Ph) but not (t)Bu(3)PO (85 degrees, >2 days), and cyclometalation competed with deoxygenation of 12 to (silox)(3)WN (11) and (silox)(3)TaO (3-Ta; DeltaG degrees (rxn)(calcd) = -100 kcal/mol). 1-V deoxygenated 12 slowly and formed stable adducts (silox)(3)V-OPR(3) (3-OPR(3)) with OPR(3). 1-Nb(4-picoline) (S = 0) and 1-NbPMe(3) (S = 1) deoxygenated R(3)PO (23 degrees C; R = Me (DeltaG degrees (rxn)(calcd from 1-Nb) = -47 kcal/mol), Ph) rapidly and 12 slowly (DeltaG degrees (rxn)(calcd) = -100 kcal/mol), and failed to deoxygenate (t)Bu(3)PO. Access to a triplet state is critical for substrate (EO) binding, and the S --> T barrier of approximately 17 kcal/mol (calcd) hinders deoxygenations by 1-Ta, while 1-V (S = 1) and 1-Nb (S --> T barrier approximately 2 kcal/mol) are competent. Once binding occurs, significant mixing with an (1)A(1) excited state derived from population of a sigma-orbital is needed to ensure a low-energy intersystem crossing of the (3)A(2) (reactant) and (1)A(1) (product) states. Correlation of a reactant sigma-orbital with a product sigma-orbital is required, and the greater the degree of bending in the (silox)(3)M-O-E angle, the more mixing energetically lowers the intersystem crossing point. The inability of substrates EO = 12 and (t)Bu(3)PO to attain a bent 90 degree angle M-O-E due to sterics explains their slow or negligible deoxygenations. Syntheses of relevant compounds and ramifications of the results are discussed. X-ray structural details are provided for 3-OPMe(3) (90 degree angle V-O-P = 157.61(9) degrees), 3-OP(t)Bu(3) ( 90 degree angle V-O-P = 180 degrees ), 1-NbPMe(3), and (silox)(3)ClWO (9).

Synthesis, electronic structure, and reactivity of strained nickel-, palladium-, and platinum-bridged [1]ferrocenophanes.

PubMed

Matas, Inmaculada; Whittell, George R; Partridge, Benjamin M; Holland, Jason P; Haddow, Mairi F; Green, Jennifer C; Manners, Ian

2010-09-29

The group 10 bis(phosphine)metalla[1]ferrocenophanes, [{Fe(η(5)-C(5)H(4))(2)}M(Pn-Bu(3))(2)] [M = Ni (4a), Pd (4b), and Pt (4c)], have been prepared by the reaction of Li(2)[Fe(η(5)-C(5)H(4))(2)]·tmeda (5, tmeda = N,N,N',N'-tetramethylethylenediamine) with trans-[MCl(2)(Pn-Bu(3))(2)] [M = Ni (trans-6a) and Pd (trans-6b)] and cis-[PtCl(2)(Pn-Bu(3))(2)] (cis-6c), respectively. Single crystal X-ray diffraction revealed highly tilted, strained structures as characterized by α angles of 28.4° (4a), 24.5° (4b), and 25.2° (4c) and a distorted square planar environment for the group 10 metal center. UV/visible spectroscopy and cyclic voltammetry indicated that all three compounds had smaller HOMO-LUMO gaps and were more electron-rich in nature than ferrocene and other comparable [1]ferrocenophanes. DFT calculations suggested that these differences were principally due to the electron-releasing nature of the M(Pn-Bu(3))(2) metal-ligand fragments. Attempts to induce thermal or anionic ring-opening polymerization of 4a-c were unsuccessful and were complicated by, for example, competing ligand dissociation processes or unfavorable chain propagation. In contrast, these species all reacted rapidly with acids effecting clean extrusion of the bis(phosphine)metal fragment. Carbon monoxide inserted cleanly into one of the palladium-carbon bonds of 4b to afford the ring-expanded, acylated product [{Fe(η(5)-C(5)H(4))(η(5)-C(5)H(4))(CO)}Pd(Pn-Bu(3))(2)] (10). The nickel analogue 4a, however, afforded [Ni(CO)(2)(Pn-Bu(3))(2)] whereas the platinum-bridged complex 4c was inert. Remarkably, all compounds 4a-c were readily oxidized by elemental sulfur to afford the [5,5']bicyclopentadienylidene (pentafulvalene) complexes [{η(4):η(0)-C(5)H(4)(C(5)H(4))}M(Pn-Bu(3))(2)] [M = Ni (11a)] and [(η(2)-C(10)H(8))M(Pn-Bu(3))(2)] [M = Pd (11b) and Pt (11c)] by a formal 4-electron oxidation of the carbocyclic ligands. Compounds 11b and 11c represent the first examples of [5,5']bicyclopentadienylidene as a neutral η(2)-ligand. The relative energies of η(2)-coordination with respect to that of η(4):η(0) bonding were investigated for 11a-c by DFT calculations.

Sodium butyrate improves the cloned yak embryo viability and corrects gene expression patterns.

PubMed

Xiong, Xian-rong; Lan, Dao-liang; Li, Jian; Wang, Yong; Zhong, Jin-cheng

2015-02-01

Interspecies somatic cell nuclear transfer (iSCNT), a powerful tool in basic scientific research, has been used widely to increase and preserve the population of endangered species. Yak (Bos grunniens) is one of these species. Development to term of interspecies cloned yak embryos has not been achieved, possibly due to abnormal epigenetic reprogramming. Previous studies have demonstrated that treatment of intraspecies cloned embryos with (NaBu) significantly improves nuclear-cytoplasmic reprogramming and viability in vitro. Therefore, in this study, we evaluated the effect of optimal NaBu concentration and exposure time on preimplantation development of yak iSCNT embryos and on the expression patterns of developmentally important genes. The results showed that 8-cell rate, blastocyst formation rate and total cell number increased significantly compared with their untreated counterparts when yak iSCNT embryos were treated with 5 nM NaBu for 12 h after activation, but that the 2-cell stage embryo rate was not significantly different. The treatment of NaBu also increased significantly the expression levels of Oct-4 and decreased the expression levels of HDAC-2, Dnmt-1 and IGF-1; the expression patterns of these genes were more similar to that of their bovine-yak in vitro fertilization (BY-IVF) counterparts. The results described above indicated that NaBu treatment improved developmental competence in vitro and 'corrected' the gene expression patterns of yak iSCNT embryos.

Electrospun Microfiber Scaffolds with Anti-Inflammatory Tributanoylated N-Acetyl-d-Glucosamine Promote Cartilage Regeneration

PubMed Central

Kim, Chaekyu; Shores, Lucas; Guo, Qiongyu; Aly, Ahmed; Jeon, Ok Hee; Kim, Do Hun; Bernstein, Nicholas; Bhattacharya, Rahul; Chae, Jemin Jeremy; Yarema, Kevin J.

2016-01-01

Tissue-engineering strategies offer promising tools for repairing cartilage damage; however, these strategies suffer from limitations under pathological conditions. As a model disease for these types of nonideal systems, the inflammatory environment in an osteoarthritic (OA) joint limits the efficacy of engineered therapeutics by disrupting joint homeostasis and reducing its capacity for regeneration. In this work, we investigated a sugar-based drug candidate, a tributanoylated N-acetyl-d-glucosamine analogue, called 3,4,6-O-Bu3GlcNAc, that is known to reduce nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling in osteoarthritis. 3,4,6-O-Bu3GlcNAc not only inhibited NFκB signaling but also exerted chondrogenic and anti-inflammatory effects on chondrocytes isolated from patients with osteoarthritis. 3,4,6-O-Bu3GlcNAc also increased the expression of extracellular matrix proteins and induced cartilage tissue production in three-dimensional in vitro hydrogel culture systems. To translate these chondrogenic and anti-inflammatory properties to tissue regeneration in osteoarthritis, we implanted 3,4,6-O-Bu3GlcNAc-loaded poly(lactic-co-glycolic acid) microfiber scaffolds into rats. The drug-laden scaffolds were biocompatible, and when seeded with human OA chondrocytes, similarly promoted cartilage tissue formation. 3,4,6-O-Bu3GlcNAc combined with the appropriate structural environment could be a promising therapeutic approach for osteoarthritis. PMID:27019285

First photometric analysis of magnetic activity and orbital period variations for the semi-detached binary BU Vulpeculae

NASA Astrophysics Data System (ADS)

Wang, Jingjing; Zhang, Bin; Yu, Jing; Liu, Liang; Tian, Xiaoman

2018-06-01

Four sets of multi-color CCD photometric observations of the close binary BU Vul were carried out for four successive months in 2010. From our observations, there are obvious variations and asymmetry of light curves on the timescale of a month, indicating high-level stellar spot activity on the surface of at least one component. The Wilson-Devinney (2010) program was used to determine the photometric solutions, which suggest that BU Vul is a semi-detached binary with the cool, less massive component filling with the critical Roche lobe. The solutions also reveal that the spots on the primary and the secondary have changed and drifted in 2010 July, August, and September. Based on analysis of the O - C curves of BU Vul, its orbital period shows a cyclic oscillation (T3 = 22.4 yr, A3 = 0.0029 d) superimposed on a secular increase. The continuous increase is possibly a result of mass transfer from the less massive component to the more massive one at a rate of dM/dt = -2.95 × 10-9 M⊙ yr-1. The cyclic variation maybe be caused by the presence of a tertiary companion with extremely low luminosity. Combined with the distortions of the light curve on 2009 November 4, we infer that BU Vul has two additional companions in a quadruple system.

Busulfan-conditioned bone marrow transplantation results in high-level allogeneic chimerism in mice made tolerant by in utero hematopoietic cell transplantation.

PubMed

Ashizuka, Shuichi; Peranteau, William H; Hayashi, Satoshi; Flake, Alan W

2006-03-01

In utero hematopoietic cell transplantation (IUHCT) is a non-ablative approach that achieves mixed allogeneic chimerism and donor-specific tolerance. However, clinical application of IUHCT has been limited by minimal engraftment. We have previously demonstrated in the murine model that low-level allogeneic chimerism achieved by IUHCT can be enhanced to near-complete donor chimerism by postnatal minimally myeloablative total body irradiation (TBI) followed by same-donor bone marrow transplantation. Because of concerns of toxicity related to even low-dose TBI in early life, we wondered if a potentially less toxic strategy utilizing a single myelosuppressive agent, Busulfan (BU), would provide similar enhancement of engraftment. In this study, mixed chimerism was created by IUHCT in a fully allogeneic strain combination. After birth, chimeric mice were conditioned with BU followed by transplantation of bone marrow cells congenic to the prenatal donor. We demonstrate that: 1) low-level chimerism after IUHCT can be converted to high-level chimerism by this protocol; 2) enhancement of chimerism is BU dose-dependent; and 3) BU reduces the proliferative potential of hematopoietic progenitor cells thus conferring a competitive advantage to the non-BU-treated postnatal donor cells. This study confirms the potential of IUHCT for facilitation of minimally toxic postnatal regimens to achieve therapeutic levels of allogeneic engraftment.

BuD, a helix–loop–helix DNA-binding domain for genome modification

PubMed Central

Stella, Stefano; Molina, Rafael; López-Méndez, Blanca; Juillerat, Alexandre; Bertonati, Claudia; Daboussi, Fayza; Campos-Olivas, Ramon; Duchateau, Phillippe; Montoya, Guillermo

2014-01-01

DNA editing offers new possibilities in synthetic biology and biomedicine for modulation or modification of cellular functions to organisms. However, inaccuracy in this process may lead to genome damage. To address this important problem, a strategy allowing specific gene modification has been achieved through the addition, removal or exchange of DNA sequences using customized proteins and the endogenous DNA-repair machinery. Therefore, the engineering of specific protein–DNA interactions in protein scaffolds is key to providing ‘toolkits’ for precise genome modification or regulation of gene expression. In a search for putative DNA-binding domains, BurrH, a protein that recognizes a 19 bp DNA target, was identified. Here, its apo and DNA-bound crystal structures are reported, revealing a central region containing 19 repeats of a helix–loop–helix modular domain (BurrH domain; BuD), which identifies the DNA target by a single residue-to-nucleotide code, thus facilitating its redesign for gene targeting. New DNA-binding specificities have been engineered in this template, showing that BuD-derived nucleases (BuDNs) induce high levels of gene targeting in a locus of the human haemoglobin β (HBB) gene close to mutations responsible for sickle-cell anaemia. Hence, the unique combination of high efficiency and specificity of the BuD arrays can push forward diverse genome-modification approaches for cell or organism redesign, opening new avenues for gene editing. PMID:25004980

Clinical use of the co-formulation of insulin degludec and insulin aspart.

PubMed

Kumar, A; Awata, T; Bain, S C; Ceriello, A; Fulcher, G R; Unnikrishnan, A G; Arechavaleta, R; Gonzalez-Gálvez, G; Hirose, T; Home, P D; Kaku, K; Litwak, L; Madsbad, S; Pinget, M; Mehta, R; Mithal, A; Tambascia, M; Tibaldi, J; Christiansen, J S

2016-08-01

To provide a review of the available data and practical use of insulin degludec with insulin aspart (IDegAsp). Premixed insulins provide basal and prandial glucose control; however, they have an intermediate-acting prandial insulin component and do not provide as effective basal coverage as true long-acting insulins, owing to the physicochemical incompatibility of their individual components, coupled with the inflexibility of adjustment. The molecular structure of the co-formulation of IDegAsp, a novel insulin preparation, allows these two molecules to coexist without affecting their individual pharmacodynamic profiles. Clinical evidence in phase 2/3 trials of IDegAsp efficacy and safety in type 1 and type 2 diabetes mellitus (T1DM and T2DM) have been assessed and summarised. In people with T2DM, once- and twice-daily dosing provides similar overall glycaemic control (HbA1c ) to current modern insulins, but with lower risk of nocturnal hypoglycaemia. In prior insulin users, glycaemic control was achieved with lower or equal insulin doses vs. other basal+meal-time or premix insulin regimens. In insulin-naïve patients with T2DM, IDegAsp can be started once or twice-daily, based on individual need. People switching from more than once-daily basal or premix insulin therapy can be converted unit-to-unit to once-daily IDegAsp, although this strategy should be assessed by the physician on an individual basis. IDegAsp offers physicians and people with T2DM a simpler insulin regimen than other available basal-bolus or premix-based insulin regimens, with stable daytime basal coverage, a lower rate of hypoglycaemia and some flexibility in injection timing compared with premix insulins. © 2016 John Wiley & Sons Ltd.

A review of the safety and efficacy data for insulin glargine 300 units/ml, a new formulation of insulin glargine.

PubMed

Dailey, G; Lavernia, F

2015-12-01

Insulin glargine 100 units/ml (Gla-100) has become a standard of care in diabetes treatment over the past decade, providing 24-h basal insulin coverage after once-daily subcutaneous injection for many people with diabetes, with a well-established efficacy and safety profile. New insulin glargine 300 units/ml (Gla-300) is a basal insulin that provides the same number of units as Gla-100 in a third of the volume. Compared with Gla-100, Gla-300 has shown more constant and prolonged pharmacokinetic (PK)/pharmacodynamic (PD) profiles. This review summarizes the findings from the EDITION series of clinical trials that investigated Gla-300 in individuals with type 1 and type 2 diabetes mellitus. Overall, Gla-300 has been shown to achieve similar glycaemic control with less, or similar, nocturnal hypoglycaemia compared with Gla-100, and a trend towards lower hypoglycaemia at any time of day. The EDITION series of clinical trials also provides some evidence for less weight gain with Gla-300 than with Gla-100. In addition, the PK/PD profiles of Gla-300 may allow more flexibility in the timing of doses, improving convenience; thus, Gla-300 could offer several positive features for individuals with diabetes requiring basal insulin therapy. © 2015 John Wiley & Sons Ltd.

47 CFR 80.385 - Frequencies for automated systems.

Code of Federal Regulations, 2014 CFR

2014-10-01

... a secondary, non-interference basis by amateur stations participating in digital message forwarding... protection will be provided to a site-based licensee's predicted 38 dBu signal level contour. The site-based licensee's predicted 38 dBu signal level contour shall be calculated using the F(50, 50) field strength...

47 CFR 80.385 - Frequencies for automated systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

... a secondary, non-interference basis by amateur stations participating in digital message forwarding... protection will be provided to a site-based licensee's predicted 38 dBu signal level contour. The site-based licensee's predicted 38 dBu signal level contour shall be calculated using the F(50, 50) field strength...

47 CFR 80.385 - Frequencies for automated systems.

Code of Federal Regulations, 2013 CFR

2013-10-01

... a secondary, non-interference basis by amateur stations participating in digital message forwarding... protection will be provided to a site-based licensee's predicted 38 dBu signal level contour. The site-based licensee's predicted 38 dBu signal level contour shall be calculated using the F(50, 50) field strength...

40 CFR 721.9516 - Siloxanes and silicones, 3-[(2-aminoethyl) amino]propyl Me, di-Me, reaction products with...

Code of Federal Regulations, 2010 CFR

2010-07-01

...-aminoethyl) amino]propyl Me, di-Me, reaction products with polyethylene-polypropylene glycol Bu glycidal..., reaction products with polyethylene-polypropylene glycol Bu glycidal ether. (a) Chemical substance and... silicones, 3-[(2-aminoethyl) amino]propyl Me, di-Me, reaction products with polyethylene-polypropylene...

40 CFR 721.9516 - Siloxanes and silicones, 3-[(2-aminoethyl) amino]propyl Me, di-Me, reaction products with...

Code of Federal Regulations, 2011 CFR

2011-07-01

...-aminoethyl) amino]propyl Me, di-Me, reaction products with polyethylene-polypropylene glycol Bu glycidal..., reaction products with polyethylene-polypropylene glycol Bu glycidal ether. (a) Chemical substance and... silicones, 3-[(2-aminoethyl) amino]propyl Me, di-Me, reaction products with polyethylene-polypropylene...

Molecular dynamics simulation of Bu4N+ in dimethylformamide: Solvation-induced volume changes

NASA Astrophysics Data System (ADS)

Kiselev, M. G.; Safonova, L. P.

2011-06-01

The structure of the Bu4N+-dimethylformamide system in the condensed and gas phases was studied by molecular dynamics simulation and quantum-chemical calculations. The calculation results were used to reveal the role played by steric effects in the volumetric characteristics of ion solvation.

Spaced planar laminations formed by repetitive basal erosion and resurgence to high-sedimentation-rate regime: new insight from a bedform-like structures and laterally continuous exposures

NASA Astrophysics Data System (ADS)

Ishihara, Yoshiro; Yuri, Onishi; Tsuda, Keisuke; Yokokawa, Miwa

2017-04-01

Spaced planar laminations (SPL), or so-called traction carpet deposits, are frequently observed in deposits of sediment gravity flows. Several sedimentation models for a succession of inversely graded units have been suggested from field observations and flume experiments. The formation of the inversely graded unit could be summarized as follows: (1) abrupt sedimentation on freezing of an inversely graded layer, or (2) interruptions in flow causing a freezing of an inversely graded layer at the most basal part of flow. In either case, traction carpets as a bed load overlying the erosive boundary at the base of flow are required. Although some descriptions have reported SPLs forming antidune bedform-like structures and the association of SPLs with structureless massive deposits have not been clearly explained. In this study, we suggest a novel model of SPL formation by repetition of basal erosion and resurgence to high-sedimentation rates, based on detail examinations of SPLs both showing bedform-like structures and lateral extents of hundreds of meters. SPLs were investigated in the Mio-Pliocene Kiyosumi Formation in central Japan and the Miocene Aoshima Formation in southwest Japan. In a turbidite in the Kiyosumi Formation, SPLs show three mound-like structures, suggesting antidune bedforms with wavelengths of about 6 to 7 m. On the upcurrent flanks, SPLs show lenticular cross laminations or pinching out of units; those units do not show clear inverse grading. Rip-up mud clasts and relatively high-angle imbrications are also observed. On the other hand, SPLs on the downcurrent flanks show relatively clear inverse grading and transition downcurrent into a massive structureless bed. In the Aoshima Formation, SPLs with ca. 1 cm unit thickness continue approximately 50 m along a palaeocurrent direction without changes in thickness. These SPLs gradually transition upward into a massive structureless unit. From the observations described above, in addition to descriptions from previous studies, it is suggested that SPLs comprising mound-like bedforms exhibit erosive conditions in the upcurrent flanks and depositional conditions in the downcurrent flanks, whereas SPLs on flat sea-floor extensively maintain their structure. Also, massive structureless beds are observed when erosion did not occur. These facts indicate that SPLs are strongly associated with an erosional process at the base of sediment gravity flows under a supercritical flow condition. The formation of SPLs does not necessary require a traction carpet and they may reflect basal erosion with a lag deposit of fine-grained particles, followed by resurgence to conditions of high sedimentation rates and massive structureless bed deposition. Repetitions of inversely graded units could occur when basal shear stresses are changed by fluctuations of flow depth, such as internal waves in a sediment gravity flow. This model can explain the concurrence of massive structureless beds with SPLs and examples of bedform-like structures without a unit thickness control.

Geriatrics. Exemplary Prevocational Programs for the Handicapped in Mississippi. PVO Unit XII--Miniunits 1-14.

ERIC Educational Resources Information Center

Chandler, David, Comp.; And Others

This unit is part of a Mississippi program designed to provide exploratory experiences and training for handicapped students, to determine if these students are capable of further vocational training or are poor risks for further occupational training, and to train students for basal skill occupations. The materials included in this unit on…

Mammary stem cells have myoepithelial cell properties

PubMed Central

Prater, Michael D.; Petit, Valérie; Russell, I. Alasdair; Giraddi, Rajshekhar; Shehata, Mona; Menon, Suraj; Schulte, Reiner; Kalajzic, Ivo; Rath, Nicola; Olson, Michael F.; Metzger, Daniel; Faraldo, Marisa M.; Deugnier, Marie-Ange; Glukhova, Marina A.; Stingl, John

2014-01-01

Contractile myoepithelial cells dominate the basal layer of the mammary epithelium and are considered to be differentiated cells. However, we observe that up to 54% of single basal cells can form colonies when seeded into adherent culture in the presence of agents that disrupt acin-myosin interactions, and on average, 65% of the single-cell-derived basal colonies can repopulate a mammary gland when transplanted in vivo. This indicates that a high proportion of basal myoepithelial cells can give rise to a mammary repopulating unit (MRU). We demonstrate that myoepithelial cells, flow-sorted using 2 independent myoepithelial-specific reporter strategies, have MRU capacity. Using an inducible lineage tracing approach we follow the progeny of α-smooth muscle actin-expressing myoepithelial cells and show that they function as long-lived lineage-restricted stem cells in the virgin state and during pregnancy. PMID:25173976

47 CFR 90.745 - Phase I licensee service areas.

Code of Federal Regulations, 2010 CFR

2010-10-01

... be defined by the predicted 38 dBu service contour of its authorized base station or fixed station... its license to relocate its initially authorized base station. The Phase I licensee's predicted 38 dBu...'s base station or fixed station. Phase I licensees are permitted to add, remove, or modify...

Synthesis of Taxol-Like Prostate Cancer Chemotherapeutic Agents

DTIC Science & Technology

2007-11-01

in Scheme 5, conventional condition utilizing n- BuLi as a base was not successful in the preparation of the desired Diels-Alder substrate 19 as only...unsuccessful. The only product obtained was n- BuLi addition to aldehyde 21. Thus, deprotonation conditions of terminal alkyne 17 or 20 are now being

Aliphatic imines in titanium-mediated reductive cross-coupling: unique reactivity of Ti(O-i-Pr)4/n-BuLi.

PubMed

Tarselli, Michael A; Micalizio, Glenn C

2009-10-15

A procedure for the coupling of aliphatic imines with allylic and allenic alkoxides is described. The success of these studies was enabled by a unique reactivity profile of Ti(IV) isopropoxide/n-BuLi compared to well-known Ti(IV) isopropoxide/RMgX systems.

Aquatic macroinvertebrate assemblages of Ghana, West Africa: understanding the ecology of a neglected tropical disease.

PubMed

Eric Benbow, M; Kimbirauskas, Ryan; McIntosh, Mollie D; Williamson, Heather; Quaye, Charles; Boakye, Daniel; Small, Pamela L C; Merritt, Richard W

2014-06-01

Buruli ulcer (BU) is an emerging, but neglected tropical disease, where there has been a reported association with disturbed aquatic habitats and proposed aquatic macroinvertebrate vectors such as biting Hemiptera. An initial step in understanding the potential role of macroinvertebrates in the ecology of BU is to better understand the entire community, not just one or two taxa, in relation to the pathogen, Mycobacterium ulcerans, at a large spatial scale. For the first time at a country-wide scale this research documents that M. ulcerans was frequently detected from environmental samples taken from BU endemic regions, but was not present in 30 waterbodies of a non-endemic region. There were significant differences in macroinvertebrate community structure and identified potential indicator taxa in relation to pathogen presence. These results suggest that specific macroinvertebrate taxa or functional metrics may potentially be used as aquatic biological indicators of M. ulcerans. Developing ecological indicators of this pathogen is a first step for understanding the disease ecology of BU and should assist future studies of transmission.

Anion-free bambus[6]uril and its supramolecular properties.

PubMed

Svec, Jan; Dusek, Michal; Fejfarova, Karla; Stacko, Peter; Klán, Petr; Kaifer, Angel E; Li, Wei; Hudeckova, Edita; Sindelar, Vladimir

2011-05-09

Methods for the preparation of anion-free bambus[6]uril (BU6) are presented. They are based on the oxidation of iodide anion, which is bound inside the macrocycle, utilizing dark oxidation by hydrogen peroxide or photooxidation in the presence of titanium dioxide. Anion-free BU6 was found to be insoluble in any of the investigated solvents; however, it dissolves in methanol/chloroform (1:1) or acetonitrile/water (1:1) mixtures in the presence of the tetrabutylammonium salt of a suitable anion. The association constants with halide ions, BF(4)(-), NO(3)(-), and CN(-), were measured by (1)H NMR spectroscopy. The highest association constant (8.9×10(5) M(-1)) was found for the 1:1 complex of BU6 with I(-) in acetonitrile/water mixture. A number of crystal structures of BU6 complexes with various anions were obtained. The influence of the anion size on the macrocycle diameter is discussed together with an unusual arrangement of the macrocycles into separate layers. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Neuroprotection and lifespan extension in Ppt1−/− mice by NtBuHA: therapeutic implications for INCL

PubMed Central

Sarkar, Chinmoy; Chandra, Goutam; Peng, Shyiong; Zhang, Zhongjian; Liu, Aiyi; Mukherjee, Anil B.

2013-01-01

Infantile neuronal ceroid lipofuscinosis (INCL) is a devastating childhood neurodegenerative lysosomal storage disease (LSD) that has no effective treatment. It is caused by inactivating mutations in the palmitoyl-protein thioesterase-1 (PPT1) gene. PPT1-deficiency impairs the cleavage of thioester linkage in palmitoylated proteins (constituents of ceroid), preventing degradation by lysosomal hydrolases. Consequently, accumulation of lysosomal ceroid leads to INCL. Thioester linkage is cleaved by nucleophilic attack. Hydroxylamine, a potent nucleophilic cellular metabolite, may have therapeutic potential for INCL but its toxicity precludes clinical application. Here we report that a hydroxylamine-derivative, N-(tert-Butyl) hydroxylamine (NtBuHA), is non-toxic, cleaves thioester linkage in palmitoylated proteins and mediates lysosomal ceroid depletion in cultured cells from INCL patients. Importantly, in Ppt1−/− mice, which mimic INCL, NtBuHA crossed the blood-brain-barrier, depleted lysosomal ceroid, suppressed neuronal apoptosis, slowed neurological deterioration and extended lifespan. Our findings provide the proof of concept that thioesterase-mimetic and antioxidant small molecules like NtBuHA are potential drug-targets for thioesterase deficiency diseases like INCL. PMID:24056696

Hydridosilylamido complexes of Ta and Mo isolobal with Berry's zirconocenes: syntheses, β-Si-H agostic interactions, catalytic hydrosilylation, and insight into mechanism.

PubMed

McLeod, Nicolas A; Kuzmina, Lyudmila G; Korobkov, Ilia; Howard, Judith A K; Nikonov, Georgii I

2016-02-14

The syntheses of novel Group 5 and Group 6 hydrosilylamido complexes of the type R(ArN[double bond, length as m-dash])M{N((t)Bu)SiMe2-H}X (M = Ta, R = Cp; M = Mo, R = ArN; X = Cl, H, OBn, Me) are described. The various substituents in the X position seem to play the key role in determining the extent of β-agostic interaction with the Si-H bond. The Mo agostic hydrido complex (ArN[double bond, length as m-dash])2Mo{η(3)-N((t)Bu)SiMe2-H}H is a pre-catalyst for the hydrosilylation of carbonyls. The stoichiometric reaction between benzaldehyde and (ArN[double bond, length as m-dash])2Mo{η(3)-N((t)Bu)SiMe2-H}H gives the benzoxy complex (ArN[double bond, length as m-dash])2Mo{N((t)Bu)SiMe2-H}(OBn), which showed a similar catalytic reactivity compared to the parent hydride. Mechanistic studies suggest that a non-hydride mechanism is operative.

Transformation of Au144(SCH2CH2Ph)60 to Au133(SPh-tBu)52 Nanomolecules: Theoretical and Experimental Study.

PubMed

Nimmala, Praneeth Reddy; Theivendran, Shevanuja; Barcaro, Giovanni; Sementa, Luca; Kumara, Chanaka; Jupally, Vijay Reddy; Apra, Edoardo; Stener, Mauro; Fortunelli, Alessandro; Dass, Amala

2015-06-04

Ultrastable gold nanomolecule Au144(SCH2CH2Ph)60 upon etching with excess tert-butylbenzenethiol undergoes a core-size conversion and compositional change to form an entirely new core of Au133(SPh-tBu)52. This conversion was studied using high-resolution electrospray mass spectrometry which shows that the core size conversion is initiated after 22 ligand exchanges, suggesting a relatively high stability of the Au144(SCH2CH2Ph)38(SPh-tBu)22 intermediate. The Au144 → Au133 core size conversion is surprisingly different from the Au144 → Au99 core conversion reported in the case of thiophenol, -SPh. Theoretical analysis and ab initio molecular dynamics simulations show that rigid p-tBu groups play a crucial role by reducing the cluster structural freedom, and protecting the cluster from adsorption of exogenous and reactive species, thus rationalizing the kinetic factors that stabilize the Au133 core size. This 144-atom to 133-atom nanomolecule's compositional change is reflected in optical spectroscopy and electrochemistry.

Interaction of Triton X-100 with acyl pocket of butyrylcholinesterase: effect on esterase activity and inhibitor sensitivity of the enzyme.

PubMed

Jaganathan, L; Boopathy, R

1998-06-01

The effect of non-ionic detergents like Triton X-100, Lubrol PX, Brij 35 and Tween 80 on the esterase activity and inhibitor sensitivity of human serum butyrylcholinesterase (BuChE) were studied. The results showed that though BuChE is not a detergent dependent enzyme, the esterase activity and inhibitor sensitivity of it can be modulated by the presence of detergents. All the detergents caused a marginal activation of the esterase activity. The presence of Lubrol PX, Brij 35 or Tween 80 did not affect the 50% molar inhibition concentration (IC50) of the inhibitors tested. But in the presence of Triton X-100 the IC50 values were increased for neostigmine, eserine and tetraisopropylpyrophosphoramide (acylation site interacting inhibitors), whereas for inhibitors like ethopropazine, imipramine and procainamide (choline binding pocket specific inhibitors) the IC50 values were unaltered. In addition, in the presence of Triton X-100 the bimolecular reaction constant for phosphorylation reaction (ki) of BuChE for the acyl pocket specific tetraisopropylpyrophosphoramide was reduced. Triton X-100 partially protected BuChE against this tetraisopropylpyrophosphoramide inactivation. These results indicate that Triton X-100 by interacting with the acyl pocket hydrophobic region is able to activate the esterase activity of BuChE. Further it reduces the capacity of the enzyme to react with inhibitors that inactivate it by interacting with the serine residue of the acylation site.

Synthesis, Biological Evaluation and Molecular Docking Study of Hydrazone-Containing Pyridinium Salts as Cholinesterase Inhibitors.

PubMed

Parlar, Sulunay; Bayraktar, Gulsah; Tarikogullari, Ayse Hande; Alptüzün, Vildan; Erciyas, Ercin

2016-01-01

A series of pyridinium salts bearing alkylphenyl groups at 1 position and hydrazone structure at 4 position of the pyridinium ring were synthesized and evaluated for the inhibition of both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes. The cholinesterase (ChE) inhibitory activity studies were carried out by using the Ellman's colorimetric method. All compounds displayed considerable AChE and BuChE inhibitory activity and some of the compounds manifested remarkable anti-AChE activity compared to the reference compound, galantamine. Among the title compounds, the series including benzofuran aromatic ring exhibited the best inhibitory activity both on AChE and BuChE enzymes. Compound 3b, 4-[2-(1-(benzofuran-2-yl)ethylidene)hydrazinyl]-1-(3-phenylpropyl)pyridinium bromide, was the most active compound with IC50 value of 0.23 (0.24) µM against enantiomeric excess (ee)AChE (human (h)AChE) while compound 3a, 4-[2-(1-(benzofuran-2-yl)ethylidene)hydrazinyl]-1-phenethylpyridinium bromide, was the most active compound with IC50 value of 0.95 µM against BuChE. Moreover, 3a and b exhibited higher activity than the reference compound galantamine (eeAChE (hAChE) IC50 0.43 (0.52) µM; BuChE IC50 14.92 µM). Molecular docking studies were carried out on 3b having highest inhibitory activity against AChE.

Burden and Historical Trend of Buruli Ulcer Prevalence in Selected Communities along the Offin River of Ghana.

PubMed

Ampah, Kobina Assan; Asare, Prince; Binnah, Daniel De-Graft; Maccaulley, Samuel; Opare, William; Röltgen, Katharina; Pluschke, Gerd; Yeboah-Manu, Dorothy

2016-04-01

Buruli ulcer (BU) is a neglected tropical skin disease caused by Mycobacterium ulcerans with more than two thirds of the global cases reported in West Africa. A nationwide active BU case search conducted in 1999 identified two health districts along the Offin River as two of the three most endemic districts in Ghana. Based on recent anecdotal accounts that transmission is unstable along the Offin River, we conducted from March to June 2013 an exhaustive household survey and active case search in 13 selected communities within a five-kilometer radius along the Offin River. The overall prevalence of BU was 2.3% among the surveyed population of 20,390 inhabitants and 477 of the total 480 cases detected (99.4%) were historical (healed) cases. By estimating the year of occurrence for each case per community and taking into account available passive surveillance records of health facilities and the District Health Directorate, we observed a general trend of continuous emergence of cases in communities located midstream the Offin River whereas downstream communities showed more sporadic patterns. We monitored the incidence of cases after the survey and recorded a cumulative incidence rate of 0.04% for the 13 communities over a 17-month active surveillance period from August 2013 to December 2014. Our data reveal an overall decline in BU incidence along the Offin River similar to the general decline in BU incidence in recent years reported by the World Health Organization for West Africa.

GSTA1 diplotypes affect busulfan clearance and toxicity in children undergoing allogeneic hematopoietic stem cell transplantation: a multicenter study.

PubMed

Ansari, Marc; Curtis, Patricia Huezo-Diaz; Uppugunduri, Chakradhara Rao S; Rezgui, Mohammed Aziz; Nava, Tiago; Mlakar, Vid; Lesne, Laurence; Théoret, Yves; Chalandon, Yves; Dupuis, Lee L; Schechter, Tao; Bartelink, Imke H; Boelens, Jaap J; Bredius, Robbert; Dalle, Jean-Hugues; Azarnoush, Saba; Sedlacek, Petr; Lewis, Victor; Champagne, Martin; Peters, Christina; Bittencourt, Henrique; Krajinovic, Maja

2017-10-31

Busulfan (BU) dose adjustment following therapeutic drug monitoring contributes to better outcome of hematopoietic stem cell transplantation (HSCT). Further improvement could be achieved through genotype-guided BU dose adjustments. To investigate this aspect, polymorphism within glutathione S transferase genes were assessed. Particularly, promoter haplotypes of the glutathione S transferase A1 ( GSTA1 ) were evaluated in vitro, with reporter gene assays and clinically, in a pediatric multi-center study (N =138) through association with BU pharmacokinetics (PK) and clinical outcomes. Promoter activity significantly differed between the GSTA1 haplotypes (p<0.001) supporting their importance in capturing PK variability. Four GSTA1 diplotype groups that significantly correlated with clearance (p=0.009) were distinguished. Diplotypes underlying fast and slow metabolizing capacity showed higher and lower BU clearance (ml/min/kg), respectively. GSTA1 diplotypes with slow metabolizing capacity were associated with higher incidence of sinusoidal obstruction syndrome, acute graft versus host disease and combined treatment-related toxicity (p<0.0005). Among other GST genes investigated, GSTP1 313GG correlated with acute graft versus host disease grade 1-4 (p=0.01) and GSTM1 non-null genotype was associated with hemorrhagic cystitis (p=0.003). This study further strengthens the hypothesis that GST diplotypes/genotypes could be incorporated into already existing population pharmacokinetic models for improving first BU dose prediction and HSCT outcomes. (N o Clinicaltrials.gov identifier: NCT01257854. Registered 8 December 2010, retrospectively registered).

GSTA1 diplotypes affect busulfan clearance and toxicity in children undergoing allogeneic hematopoietic stem cell transplantation: a multicenter study

PubMed Central

Ansari, Marc; Curtis, Patricia Huezo-Diaz; Uppugunduri, Chakradhara Rao S.; Rezgui, Mohammed Aziz; Nava, Tiago; Mlakar, Vid; Lesne, Laurence; Théoret, Yves; Chalandon, Yves; Dupuis, Lee L.; Schechter, Tao; Bartelink, Imke H.; Boelens, Jaap J.; Bredius, Robbert; Dalle, Jean-Hugues; Azarnoush, Saba; Sedlacek, Petr; Lewis, Victor; Champagne, Martin; Peters, Christina; Bittencourt, Henrique; Krajinovic, Maja

2017-01-01

Busulfan (BU) dose adjustment following therapeutic drug monitoring contributes to better outcome of hematopoietic stem cell transplantation (HSCT). Further improvement could be achieved through genotype-guided BU dose adjustments. To investigate this aspect, polymorphism within glutathione S transferase genes were assessed. Particularly, promoter haplotypes of the glutathione S transferase A1 (GSTA1) were evaluated in vitro, with reporter gene assays and clinically, in a pediatric multi-center study (N =138) through association with BU pharmacokinetics (PK) and clinical outcomes. Promoter activity significantly differed between the GSTA1 haplotypes (p<0.001) supporting their importance in capturing PK variability. Four GSTA1 diplotype groups that significantly correlated with clearance (p=0.009) were distinguished. Diplotypes underlying fast and slow metabolizing capacity showed higher and lower BU clearance (ml/min/kg), respectively. GSTA1 diplotypes with slow metabolizing capacity were associated with higher incidence of sinusoidal obstruction syndrome, acute graft versus host disease and combined treatment-related toxicity (p<0.0005). Among other GST genes investigated, GSTP1 313GG correlated with acute graft versus host disease grade 1-4 (p=0.01) and GSTM1 non-null genotype was associated with hemorrhagic cystitis (p=0.003). This study further strengthens the hypothesis that GST diplotypes/genotypes could be incorporated into already existing population pharmacokinetic models for improving first BU dose prediction and HSCT outcomes. (No Clinicaltrials.gov identifier: NCT01257854. Registered 8 December 2010, retrospectively registered). PMID:29207608

Regulation of osteogenesis of human amniotic mesenchymal stem cells by sodium butyrate.

PubMed

Fan, Xiaoting; Li, Lei; Ye, Zhaoyang; Zhou, Yan; Tan, Wen-Song

2018-04-01

Human amniotic membrane-derived mesenchymal stem cells (hAMSCs) draw great interests for regenerative medicine due to convenient availability and low immunogenicity. However, suboptimal culture conditions limit their application. In recent years, small molecules have proven powerful in regulating stem cell fates and can be applied to stimulate their function. In the present study, the impacts of sodium butyrate (NaBu), a histone deacetylase inhibitor (HDACi), on hAMSCs were investigated. It was shown that NaBu at a low concentration inhibited cell proliferation by arresting cell cycle at G0/G1 rather than inducing apoptosis. When NaBu was supplemented at a concentration of <1.0 mM for 3 days during osteogenic induction, significantly more mineralized nodules were generated and the expression of osteogenesis-related genes (ALP, Runx2, Opn, and Ocn) and proteins (Col1a1, OPN, OCN, Runx2, and TAZ) were both significantly enhanced. However, a higher concentration (1.0 mM) and longer exposure time (14 days) of NaBu showed no such effects, which may be partially attributed to both the increased expression of histone deacetylase 8 (HDAC8) and reduced level of H3K9-Ace, thus leading to the transcriptional inhibition during osteogenesis. Further, it was indicated that ERK might be involved in the stimulatory effects of NaBu. These findings may be helpful to develop an efficient culture process for hAMSCs towards bone regeneration. © 2018 International Federation for Cell Biology.

AF64A depletes hippocampal high-affinity choline uptake but does not alter the density of alpha-bungarotoxin binding sites or modify the effect of exogenous choline.

PubMed

Morley, B J; Garner, L L

1990-06-11

Sodium-dependent, high-affinity choline uptake (HACU) and the density of alpha-bungarotoxin (BuTX) receptor-binding sites were measured in the hippocampus following the intraventricular infusion of ethylcholine aziridinium ion (AF64A), a neurotoxin that competes with choline at high-affinity choline transport sites and may result in the degeneration of cholinergic axons. Eight days after the infusion of AF64A into the lateral ventricles (2.5 nmol/side), HACU was depleted by 60% in the hippocampus of experimental animals in comparison with controls, but the density of BuTX-binding sites was not altered. The administration of 15 mg/ml of choline chloride in the drinking water increased the density of BuTX-binding sites, as previously reported by this laboratory. The administration of AF64A did not prevent the effect of exogenous choline on the density of binding sites, nor did choline treatment alter the effect of AF64A on HACU. These data indicate that the density of BuTX-binding sites in the hippocampus is not altered following a substantial decrease in HACU and presumed degeneration of cholinergic axons. Since the effect of exogenous choline was not prevented by AF64A treatment, the data are interpreted to support the hypothesis that the increase in the density of BuTX-binding sites following dietary choline supplementation is attributable to a direct effect of choline on receptor sites.

Spontaneous Healing of Mycobacterium ulcerans Lesions in the Guinea Pig Model

PubMed Central

Silva-Gomes, Rita; Marcq, Elly; Trigo, Gabriela; Gonçalves, Carine M.; Longatto-Filho, Adhemar; Castro, António G.; Pedrosa, Jorge; Fraga, Alexandra G.

2015-01-01

Buruli Ulcer (BU) is a necrotizing skin disease caused by Mycobacterium ulcerans infection. BU is characterized by a wide range of clinical forms, including non-ulcerative cutaneous lesions that can evolve into severe ulcers if left untreated. Nevertheless, spontaneous healing has been reported to occur, although knowledge on this process is scarce both in naturally infected humans and experimental models of infection. Animal models are useful since they mimic different spectrums of human BU disease and have the potential to elucidate the pathogenic/protective pathway(s) involved in disease/healing. In this time-lapsed study, we characterized the guinea pig, an animal model of resistance to M. ulcerans, focusing on the macroscopic, microbiological and histological evolution throughout the entire experimental infectious process. Subcutaneous infection of guinea pigs with a virulent strain of M. ulcerans led to early localized swelling, which evolved into small well defined ulcers. These macroscopic observations correlated with the presence of necrosis, acute inflammatory infiltrate and an abundant bacterial load. By the end of the infectious process when ulcerative lesions healed, M. ulcerans viability decreased and the subcutaneous tissue organization returned to its normal state after a process of continuous healing characterized by tissue granulation and reepethelialization. In conclusion, we show that the experimental M. ulcerans infection of the guinea pig mimics the process of spontaneous healing described in BU patients, displaying the potential to uncover correlates of protection against BU, which can ultimately contribute to the development of new prophylactic and therapeutic strategies. PMID:26625302

Risk factors for Mycobacterium ulcerans infection (Buruli Ulcer) in Togo ─ a case-control study in Zio and Yoto districts of the maritime region.

PubMed

Maman, Issaka; Tchacondo, Tchadjobo; Kere, Abiba Banla; Piten, Ebekalisai; Beissner, Marcus; Kobara, Yiragnima; Kossi, Komlan; Badziklou, Kossi; Wiedemann, Franz Xaver; Amekuse, Komi; Bretzel, Gisela; Karou, Damintoti Simplice

2018-01-19

Buruli ulcer (BU) is a neglected mycobacterial skin infection caused by Mycobacterium ulcerans. This disease mostly affects poor rural populations, especially in areas with low hygiene standards and sanitation coverage. The objective of this study was to identify these risk factors in the districts of Zio and Yoto of the Maritime Region in Togo. We conducted a case-control study in Zio and Yoto, two districts proved BU endemic from November 2014 to May 2015. BU cases were diagnosed according to the WHO clinical case definition at the Centre Hospitalier Régional de Tsévié (CHR Tsévié) and confirmed by Ziehl-Neelsen (ZN) microscopy and IS2404 polymerase chain reaction (PCR). For each case, up to two controls matched by sex and place of residence were recruited. Socio-demographic, environmental or behavioral data were collected and conditional logistic regression analysis was used to identify and compare risk factors between BU cases and controls. A total of 83 cases and 128 controls were enrolled. The median age was 15 years (range 3-65 years). Multivariate conditional logistic regression analysis after adjustment for potential confounders identified age (< 10 years (OR =11.48, 95% CI = 3.72-35.43) and 10-14 years (OR = 3.63, 95% CI = 1.22-10.83)), receiving insect bites near a river (OR = 7.8, 95% CI = 1.48-41.21) and bathing with water from open borehole (OR = 5.77, (1.11-29.27)) as independent predictors of acquiring BU infection. This study identified age, bathing with water from open borehole and receiving insect bites near a river as potential risk of acquiring BU infection in Zio and Yoto districts of the Maritime Region in south Togo.

Vapochromic ionic liquids from metal-chelate complexes exhibiting reversible changes in color, thermal, and magnetic properties.

PubMed

Funasako, Yusuke; Mochida, Tomoyuki; Takahashi, Kazuyuki; Sakurai, Toshihiro; Ohta, Hitoshi

2012-09-17

Vapor- and gas-responsive ionic liquids (ILs) comprised of cationic metal-chelate complexes and bis(trifluoromethanesulfonyl)imide (Tf(2)N) have been prepared, namely, [Cu(acac)(BuMe(3)en)][Tf(2)N] (1 a), [Cu(Bu-acac)(BuMe(3)en)][Tf(2)N] (1 b), [Cu(C(12)-acac)(Me(4)en)][Tf(2)N] (1 c), [Cu(acac)(Me(4)en)][Tf(2)N] (1 d), and [Ni(acac)(BuMe(3)en)][Tf(2)N] (2 a) (acac = acetylacetonate, Bu-acac = 3-butyl-2,4-pentanedionate, C(12)-acac = 3-dodecyl-2,4-pentanedionate, BuMe(3)en = N-butyl-N,N',N'-tetramethylethylenediamine, and Me(4)en = N,N,N',N'-trimethylethylenediamine). These ILs exhibited reversible changes in color, thermal properties, and magnetic properties in response to organic vapors and gases. The Cu(II)-containing ILs are purple and turn blue-purple to green when exposed to organic vapors, such as acetonitrile, methanol, and DMSO, or ammonia gas. The color change is based on the coordination of the vapor molecules to the cation, and the resultant colors depend on the coordination strength (donor number, DN) of the vapor molecules. The vapor absorption caused changes in the melting points and viscosities, leading to alteration in the phase behaviors. The IL with a long alkyl chain (1 d) transitioned from a purple solid to a brown liquid at its melting point. The Ni(II)-containing IL (2 a) is a dark red diamagnetic liquid, which turned into a green paramagnetic liquid by absorbing vapors with high DN. Based on the equilibrium shift from four- to six-coordinated species, the liquid exhibited thermochromism and temperature-dependent magnetic susceptibility after absorbing methanol. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Synergistic effect of concanavalin A and Bu-WSA on DNA synthesis in human peripheral blood lymphocytes.

PubMed

Nitta, T; Okumura, S; Nakano, M

1985-02-01

Butanol-extracted water soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii was not mitogenic for human peripheral blood mononuclear cells (PBM) but was capable of enhancing (3H) thymidine uptake of T cells stimulated by concanavalin A (Con A) in the presence of B cells or macrophages (M phi) in vitro. The mechanisms of the synergy of Con A and Bu-WSA were studied by using separated cell populations from PBM. Both subfractioned OKT4+ and OKT8+ cells were responsive to co-stimulation by Con A and Bu-WSA in the presence of an accessory cell population. Allogeneic B cells and M phi as well as autologous cells had helper function as accessory cells. Heavy irradiation with gamma-rays did not affect the function of the accessory cells, but previous treatment of B cells with anti-Ig serum plus complement (C) or treatment of M phi with anti-M phi serum plus C deprived them of their function. The treatment of accessory cells with anti-HLA-DR serum, regardless of the presence or absence of C, resulted in loss of their helper function. Cultures in Marbrook-type vessels showed that a mixed cell population of T cells and accessory cells in the lower chamber produced some active factor(s) after co-stimulation with Con A and Bu-WSA, and by passing through the membrane filter separating the chambers, the factor(s) enhanced the proliferation of the Con A-activated T cell population in the upper chamber. The factor(s) was presumed to be interleukin 2 (IL 2), because it supported the growth of IL 2-dependent CTLL cells. These results indicate that the synergy of Con A and Bu-WSA on the proliferative response of human PBM is due to the elevation of growth factor production from T cells stimulated by those mitogens.

Guanidinophosphazenes: design, synthesis, and basicity in THF and in the gas phase.

PubMed

Kolomeitsev, Alexander A; Koppel, Ilmar A; Rodima, Toomas; Barten, Jan; Lork, Enno; Röschenthaler, Gerd-Volker; Kaljurand, Ivari; Kütt, Agnes; Koppel, Ivar; Mäemets, Vahur; Leito, Ivo

2005-12-21

A principle for creating a new generation of nonionic superbases is presented. It is based on attachment of tetraalkylguanidino, 1,3-dimethylimidazolidine-2-imino, or bis(tetraalkylguanidino)carbimino groups to the phosphorus atom of the iminophosphorane group using tetramethylguanidine or easily available 1,3-dimethylimidazolidine-2-imine. Seven new nonionic superbasic phosphazene bases, tetramethylguanidino-substituted at the P atom, have been synthesized. Their base strengths are established in tetrahydrofuran (THF) solution by means of spectrophotometric titration and compared with those of eight reference superbases designed specially for this study, P2- and P4-iminophosphoranes. The gas-phase basicities of several guanidino- and N',N',N'',N''-tetramethylguanidino (tmg)-substituted phosphazenes and their cyclic analogues are calculated, and the crystal structures of (tmg)3P=N-t-Bu and (tmg)3P=N-t-Bu x HBF4 are determined. The enormous basicity-increasing effect of this principle is experimentally verified for the tetramethylguanidino groups in the THF medium: the basicity increase when moving from (dma)3P=N-t-Bu (pKalpha = 18.9) to (tmg)3P=N-t-Bu (pKalpha = 29.1) is 10 orders of magnitude. A significantly larger basicity increase (up to 20 powers of 10) is expected (based on the high-level density functional theory calculations) to accompany the similar gas-phase transfer between the (dma)3P=NH and (tmg)3P=NH bases. Far stronger basicities still are expected when, in the latter two compounds, all three dimethylamino (or tetramethylguanidino) fragments are replaced by methylated triguanide fragments, (tmg)2C=N-. The gas-phase basicity (around 300-310 kcal/mol) of the resulting base, [(tmg)2C=N-]3P=NH, having only one phosphorus atom, is predicted to exceed the basicity of (dma)3P=NH by more than 40 powers of 10 and to surpass also the basicity of the widely used commercial [(dma)3P=N]3P=N-t-Bu (t-BuP4) superbase.

Ocimum basilicum L.: phenolic profile and antioxidant-related activity.

PubMed

Dorman, H J Damien; Hiltunen, Raimo

2010-01-01

Ocimum basilicum L. leaf material was extracted by maceration with (80:20:1 v/v/v) methanol: water: acetic acid to produce a crude extract (CE), which was further fractionated by liquid-liquid extraction to isolate light petroleum (PE), ethyl acetate (EtOAc), n-butanol (n-BuOH) and H2O-soluble sub-fractions. The total phenol and flavonoid contents of the resulting samples were estimated using colorimetric-based methods, and their iron(III) reductive and free radical scavenging activities were determined in a battery of in vitro assays. The CE and sub-fractions contained phenolic compounds and flavonoids. The samples, except for PE, gave a positive result for the presence of flavones and flavonols; however, flavanones only appeared to be present in the CE. In iron(III) reduction, CE and n-BuOH were the most potent followed by EtOAc and H2O (statistically indistinguishable, p > 0.05). However, in the ferric reducing antioxidant power assay, H2O was the most potent followed by CE and EtOAc (statistically indistinguishable, p > 0.05) and n-BuOH and PE. In 1,1-diphenyl-2-picrylhydrazyl scavenging, all the samples, except PE, were effective against this reactive nitrogen species, with CE, EtOAc and n-BuOH being the most potent (statistically indistinguishable, p > 0.05). In alkylperoxyl scavenging, all the samples, except for PE, were effective against this reactive oxygen species (ROS). In superoxide anion scavenging, all the samples were capable of scavenging this ROS with CE being the most effective, followed by n-BuOH and H2O (statistically indistinguishable, p > 0.05) and EtOAc and PE. Similarly, in hydroxyl scavenging, all the samples were capable of scavenging this ROS with CE and n-BuOH being the most effective (statistically indistinguishable, p > 0.05) followed by EtOAc and H2O (statistically indistinguishable, p > 0.05) and PE.

Deuteron-induced reactions on Ni isotopes up to 60 MeV

NASA Astrophysics Data System (ADS)

Avrigeanu, M.; Šimečková, E.; Fischer, U.; Mrázek, J.; Novak, J.; Štefánik, M.; Costache, C.; Avrigeanu, V.

2016-07-01

Background: The high complexity of the deuteron-nucleus interaction from the deuteron weak binding energy of 2.224 MeV is also related to a variety of reactions induced by the deuteron-breakup (BU) nucleons. Thus, specific noncompound processes as BU and direct reactions (DR) make the deuteron-induced reactions so different from reactions with other incident particles. The scarce consideration of only pre-equilibrium emission (PE) and compound-nucleus (CN) mechanisms led to significant discrepancies with experimental results so that recommended reaction cross sections of high-priority elements as, e.g., Ni have mainly been obtained by fit of the data. Purpose: The unitary and consistent BU and DR account in deuteron-induced reactions on natural nickel may take advantage of an extended database for this element, including new accurate measurements of particular reaction cross sections. Method: The activation cross sections of 64,61,60Cu, Ni,5765, and 55,56,57,58,59m,60Co nuclei for deuterons incident on natural Ni at energies up to 20 MeV, were measured by the stacked-foil technique and high-resolution gamma spectrometry using U-120M cyclotron of CANAM, NPI CAS. Then, within an extended analysis of deuteron interactions with Ni isotopes up to 60 MeV, all processes from elastic scattering until the evaporation from fully equilibrated compound system have been taken into account while an increased attention is paid especially to the BU and DR mechanisms. Results: The deuteron activation cross-section analysis, completed by consideration of the PE and CN contributions corrected for decrease of the total-reaction cross section from the leakage of the initial deuteron flux towards BU and DR processes, is proved satisfactory for the first time to all available data. Conclusions: The overall agreement of the measured data and model calculations validates the description of nuclear mechanisms taken into account for deuteron-induced reactions on Ni, particularly the BU and DR that should be considered explicitly.

Leaf mass per area, not total leaf area, drives differences in above-ground biomass distribution among woody plant functional types.

PubMed

Duursma, Remko A; Falster, Daniel S

2016-10-01

Here, we aim to understand differences in biomass distribution between major woody plant functional types (PFTs) (deciduous vs evergreen and gymnosperm vs angiosperm) in terms of underlying traits, in particular the leaf mass per area (LMA) and leaf area per unit stem basal area. We used a large compilation of plant biomass and size observations, including observations of 21 084 individuals on 656 species. We used a combination of semiparametric methods and variance partitioning to test the influence of PFT, plant height, LMA, total leaf area, stem basal area and climate on above-ground biomass distribution. The ratio of leaf mass to above-ground woody mass (MF /MS ) varied strongly among PFTs. We found that MF /MS at a given plant height was proportional to LMA across PFTs. As a result, the PFTs did not differ in the amount of leaf area supported per unit above-ground biomass or per unit stem basal area. Climate consistently explained very little additional variation in biomass distribution at a given plant size. Combined, these results demonstrate consistent patterns in above-ground biomass distribution and leaf area relationships among major woody PFTs, which can be used to further constrain global vegetation models. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Illness meanings and experiences for pre-ulcer and ulcer conditions of Buruli ulcer in the Ga-West and Ga-South Municipalities of Ghana.

PubMed

Ackumey, Mercy M; Gyapong, Margaret; Pappoe, Matilda; Kwakye-Maclean, Cynthia; Weiss, Mitchell G

2012-05-11

Ghana is a Buruli ulcer (BU) endemic country yet there is paucity of socio-cultural research on BU. Examining distinctive experiences and meanings for pre-ulcers and ulcers of BU may clarify the disease burden, illness experience and local perceptions of causes and spread, and environmental features of BU, which are useful to guide public health programmes and future research. This study aimed to explain local meanings and experiences of BU for persons with pre-ulcers and ulcers in the Ga-West and Ga-South municipalities in Accra. Semi-structured interviews based on the Explanatory Model Interview Catalogue framework were administered to 181 respondents comprising 15 respondents with pre-ulcers and 166 respondents with ulcers. The Wilcoxon rank-sum test was used to compare categories of illness experiences (PD) and perceived causes (PC) among respondents with pre-ulcer and ulcer conditions. The Fisher's exact test was used to compare the most troubling PD and the most important PC variables. Qualitative phenomenological analysis of respondents' narratives clarified illness experiences and meanings with reference to PC and PD variables. Families of respondents with pre-ulcers and the respondents themselves were often anxious about disease progression, while families of respondents with ulcers, who had to give care, worried about income loss and disruption of school attendance. Respondents with pre-ulcers frequently reported swimming in ponds and rivers as a perceived cause and considered it as the most important PC (53.3%). Respondents with ulcers frequently attributed their BU illness to witchcraft (64.5%) and respondents who claimed they had no water contact, questioned the credibility of health messages Affected persons with pre-ulcers are likely to delay treatment because of social and financial constraints and the absence of pain. Scepticism on the role of water in disease contagion and prolonged healing is perceived to make ideas of witchcraft as a PC more credible, among respondents with ulcers. Health messages should address issues of locally perceived risk and vulnerability. Guided by study findings, further research on the role of environmental, socio-cultural and genetic factors in BU contagion, is also needed to clarify and formulate health messages and strengthen public health initiatives.

Illness meanings and experiences for pre-ulcer and ulcer conditions of Buruli ulcer in the Ga-West and Ga-South Municipalities of Ghana

PubMed Central

2012-01-01

Background Ghana is a Buruli ulcer (BU) endemic country yet there is paucity of socio-cultural research on BU. Examining distinctive experiences and meanings for pre-ulcers and ulcers of BU may clarify the disease burden, illness experience and local perceptions of causes and spread, and environmental features of BU, which are useful to guide public health programmes and future research. This study aimed to explain local meanings and experiences of BU for persons with pre-ulcers and ulcers in the Ga-West and Ga-South municipalities in Accra. Methods Semi-structured interviews based on the Explanatory Model Interview Catalogue framework were administered to 181 respondents comprising 15 respondents with pre-ulcers and 166 respondents with ulcers. The Wilcoxon rank-sum test was used to compare categories of illness experiences (PD) and perceived causes (PC) among respondents with pre-ulcer and ulcer conditions. The Fisher’s exact test was used to compare the most troubling PD and the most important PC variables. Qualitative phenomenological analysis of respondents’ narratives clarified illness experiences and meanings with reference to PC and PD variables. Results Families of respondents with pre-ulcers and the respondents themselves were often anxious about disease progression, while families of respondents with ulcers, who had to give care, worried about income loss and disruption of school attendance. Respondents with pre-ulcers frequently reported swimming in ponds and rivers as a perceived cause and considered it as the most important PC (53.3%). Respondents with ulcers frequently attributed their BU illness to witchcraft (64.5%) and respondents who claimed they had no water contact, questioned the credibility of health messages Conclusions Affected persons with pre-ulcers are likely to delay treatment because of social and financial constraints and the absence of pain. Scepticism on the role of water in disease contagion and prolonged healing is perceived to make ideas of witchcraft as a PC more credible, among respondents with ulcers. Health messages should address issues of locally perceived risk and vulnerability. Guided by study findings, further research on the role of environmental, socio-cultural and genetic factors in BU contagion, is also needed to clarify and formulate health messages and strengthen public health initiatives. PMID:22471884

Exploring the intermolecular interactions acting in solvent-modified MEKC by Molecular Dynamics and NMR: The effect of n-butanol on the separation of diclofenac and its impurities.

PubMed

Caprini, Claudia; Pasquini, Benedetta; Melani, Fabrizio; Del Bubba, Massimo; Giuffrida, Alessandro; Calleri, Enrica; Orlandini, Serena; Furlanetto, Sandra

2018-02-05

An integrated approach involving CE experiments, Molecular Dynamics (MD) simulations and two-dimensional NOE spectroscopy (2D-NOESY) experiments was employed to elucidate the intermolecular interactions and the separation mechanisms involved in a solvent-modified MEKC method for the simultaneous determination of diclofenac sodium and its impurities. The CE findings indicated that the addition of n-butanol (nBuOH) to the SDS micellar solution played a primary role for controlling the partitioning into the mixed micelles and the migration of the analytes and that the presence of nBuOH as cosurfactant was compulsory for achieving the complete separation of the compounds. The different capacity factors of the analytes were calculated and a change in solute association with the mixed micelle when changing the SDS/nBuOH molar ratio was highlighted. The optimal SDS/nBuOH molar ratio for the electrophoretic separation was 1:8. On the other hand, both MD simulations and NMR experiments indicated that the most favorable molar ratio for the formation of mixed SDS/nBuOH micelles was 1:2. These results suggested that probably there is an excess of nBuOH in the background electrolyte, both as free molecules and in form of aggregates, which is able to interact with the analytes, and thus may compete with mixed micelles for the considered compounds. The calculated values of gain in potential energy of the analytes when included in mixed micelles were in agreement with the observed migration order of the compounds. The role of methyl-β-cyclodextrin (MβCyD) in the background electrolyte was also investigated, since the addition of this CyD to the solvent-modified MEKC system was found to be useful to reduce the analysis time. MD simulations and 2D-NOESY spectra highlighted the formation of inclusion complexes with MβCyD not only with the analytes, but also with SDS. MβCyD may lower the availability of both SDS and nBuOH for forming micelles and mostly may compete with the mixed micelle as a second pseudostationary phase. Copyright © 2017 Elsevier B.V. All rights reserved.

Differential effects of developmental hypo- and hyperthyroidism on acetylcholinesterase and butyrylcholinesterase activity in the spinal cord of developing postnatal rat pups.

PubMed

Koohestani, Faezeh; Brown, Chester M; Meisami, Esmail

2012-11-01

The plasticity and vulnerability of the rat spinal cord (SC) during postnatal development has been less investigated compared to other CNS structures. In this study, we determined the effects of thyroid hormonal (TH) deficiency and excess on postnatal growth and neurochemical development of the rat SC. The growth as well as the specific and total activity of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes of the SC were determined in hypo- and hyperthyroid rat pups at postnatal (P) days P1, P5, P10 and P21 (weaning), and were compared to age-matched untreated normal controls. AChE is a cholinergic synaptic enzyme while BuChE is a metabolic enzyme mainly found in glial cells and neurovascular cells. The SC is rich in somatic motor, autonomic cholinergic neurons and associated interneurons. Daily subcutaneous injection of pups with thyroxine (T4) and administration of antithyroid goitrogen propylthiouracil (PTU) in the litter's drinking water were used to induce hyper- and hypothyroidism, respectively. Enzyme assays were carried out spectrophotometrically at the above-mentioned ages, using SC homogenates with acetylthiocholine-chloride as the substrate, together with specific cholinesterase inhibitors, which specifically target AChE and BuChE. SC weights were significantly lower at P10 and P21 in hypothyroid pups but unchanged in the hyperthyroid ones. Hypothyroidism significantly reduced both specific and total AChE activity in SC of P10 and P21 rat pups, while having no effects on the BuChE activity, although total BuChE activity was decreased due to reduced total tissue weight. In contrast both specific and total AChE activities were markedly and significantly increased (>100%) in the P10 and P21 hyperthyroid pups. However, BuChE specific activity was unaffected by this treatment. The results indicate that hypothyroid condition significantly reduces, while hyperthyroidism increases, the postnatal development of cholinergic synapses, thereby influencing the functional development of this major sensory and motor structure. However, the neurochemical development of glia and other non-neuronal cells, where BuChE is mainly localized, is comparatively unaffected in these abnormal developmental conditions. Copyright © 2012 ISDN. Published by Elsevier Ltd. All rights reserved.

Ex situ generation of stoichiometric HCN and its application in the Pd-catalysed cyanation of aryl bromides: evidence for a transmetallation step between two oxidative addition Pd-complexes.

PubMed

Kristensen, Steffan K; Eikeland, Espen Z; Taarning, Esben; Lindhardt, Anders T; Skrydstrup, Troels

2017-12-01

A protocol for the Pd-catalysed cyanation of aryl bromides using near stoichiometric and gaseous hydrogen cyanide is reported for the first time. A two-chamber reactor was adopted for the safe liberation of ex situ generated HCN in a closed environment, which proved highly efficient in the Ni-catalysed hydrocyanation as the test reaction. Subsequently, this setup was exploited for converting a range of aryl and heteroaryl bromides (28 examples) directly into the corresponding benzonitriles in high yields, without the need for cyanide salts. Cyanation was achieved employing the Pd(0) precatalyst, P( t Bu) 3 -Pd-G3 and a weak base, potassium acetate, in a dioxane-water solvent mixture. The methodology was also suitable for the synthesis of 13 C-labelled benzonitriles with ex situ generated 13 C-hydrogen cyanide. Stoichiometric studies with the metal complexes were undertaken to delineate the mechanism for this catalytic transformation. Treatment of Pd(P( t Bu) 3 ) 2 with H 13 CN in THF provided two Pd-hydride complexes, (P( t Bu) 3 ) 2 Pd(H)( 13 CN), and [(P( t Bu) 3 )Pd(H)] 2 Pd( 13 CN) 4 , both of which were isolated and characterised by NMR spectroscopy and X-ray crystal structure analysis. When the same reaction was performed in a THF : water mixture in the presence of KOAc, only (P( t Bu) 3 ) 2 Pd(H)( 13 CN) was formed. Subjection of this cyano hydride metal complex with the oxidative addition complex (P( t Bu) 3 )Pd(Ph)(Br) in a 1 : 1 ratio in THF led to a transmetallation step with the formation of (P( t Bu) 3 ) 2 Pd(H)(Br) and 13 C-benzonitrile from a reductive elimination step. These experiments suggest the possibility of a catalytic cycle involving initially the formation of two Pd(ii)-species from the oxidative addition of L n Pd(0) into HCN and an aryl bromide followed by a transmetallation step to L n Pd(Ar)(CN) and L n Pd(H)(Br), which both reductively eliminate, the latter in the presence of KOAc, to generate the benzonitrile and L n Pd(0).

Experimental studies of rotating exchange flow

NASA Astrophysics Data System (ADS)

Rabe, B.; Smeed, D. A.; Dalziel, S. B.; Lane-Serff, G. F.

2007-02-01

Ocean basins are connected by straits and passages, geometrically limiting important heat and salt exchanges which in turn influence the global thermohaline circulation and climate. Such exchange can be modeled in an idealized way by taking into consideration the density-driven two-layer flow along a strait under the influence of rotation. We use a laboratory model of a lock exchange between two reservoirs of different density through a flat-bottom channel with a horizontal narrows, set up on two different platforms: a 1 m diameter turntable, where density interface position was measured by dye attenuation, and the 14 m diameter turntable at Coriolis/LEGI (Grenoble, France), where correlation imaging velocimetry, a particle imaging technique, allowed us to obtain for the first time detailed measurements of the velocity fields in these flows. The influence of rotation is studied by varying a parameter, Bu, a type of Burger number given by the ratio of the Rossby radius to the channel width at the narrows. In addition, a two-layer version of the Miami Isopycnic Coordinate Model (MICOM) is used, to study the cases with low Burger number. Results from experiments by Dalziel [1988. Two-layer hydraulics: maximal exchange flows. Ph.D. Thesis, Department of Applied Mathematics and Theoretical Physics, University of Cambridge, see also ] are also included for comparison. Time-mean exchange fluxes for any Bu are in close agreement with the inviscid zero-potential vorticity theory of Dalziel [1990. Rotating two-layer sill flows. In: Pratt, L.J. (Ed.), The Physical Oceanography of Sea Straits. Kluwer Academic, Dordrecht, pp. 343-371] and Whitehead et al. [1974. Rotating hydraulics of strait and sill flows. Geophysical Fluid Dynamics 6, 101-125], who found that fluxes for Bu>1 mainly vary with channel width, similar to non-rotating flow, but for Bu<1 are only limited by the Rossby radius. We also show theoretically that non-zero-potential vorticity results in only a small increase in the predicted exchange flux around Bu˜1. The flow characteristics are found to be very different for small and large Burger numbers: for Bu>1 a steady, two-layer flow was observed that persisted across the channel at the narrows with only some across-channel variation. The distribution of the Froude number is found to give some evidence for hydraulic control in a manner similar to that of non-rotating flows under the influence of bottom drag. Flow for Bu<0.5 does not appear to reach a steady state but instead is characterized by an unsteady, meandering current and several eddies in the strait. Similar instabilities also occur in wide oceanic straits, where several mechanisms, such as barotropic and baroclinic instability, have been proposed and could also be one cause of time variability in our experiments. Both the laboratory experiments and the MICOM results suggest that in the presence of bottom drag or side wall friction some features of the flow, such as the location of the channel crossing, become sensitive to the initial conditions. These effects differ in flows with Bu>1 and Bu<1.

Airport Activity Statistics of Certificated Route Air Carriers, 1993

DTIC Science & Technology

1993-12-31

29 .29 BU FFALO ......................................................................................... TO TA L ...................... S NS 121.58...FREIGHT MAIL PREIG$ CARRIlER HUB % OF ENPLANEMENTS AND MAIL ALASKA--Continued BARROW-Continued (WILEY POST-WILL ROGERS MEM)-Continued NO RTHERf" AIR...TOTAL ............. ..... 1090 1090 NS 31869 31869 AS 32959 32959 AV ATLANTIC .. .............................. .. . TOTAL S NS 3.074 AS 3.074 BU

Aliphatic Imines in Titanium-Mediated Reductive Cross-Coupling: Unique Reactivity of Ti(Oi-Pr)4/n-BuLi

PubMed Central

Tarselli, Michael A.; Micalizio, Glenn C.

2009-01-01

A procedure for the coupling of aliphatic imines with allylic and allenic alkoxides is described. The success of these studies was enabled by a unique reactivity profile of Ti(IV) isopropoxide/n-BuLi compared to well-known Ti(IV) isopropoxide/R-MgX systems. PMID:19810765

40 CFR 721.2535 - Benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Benzene, 1,1â²-methylanebis[4... Significant New Uses for Specific Chemical Substances § 721.2535 Benzene, 1,1′-methylanebis[4-isocyanato... chemical substance identified as benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked...

40 CFR 721.2535 - Benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Benzene, 1,1â²-methylanebis[4... Significant New Uses for Specific Chemical Substances § 721.2535 Benzene, 1,1′-methylanebis[4-isocyanato... chemical substance identified as benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked...

40 CFR 721.2535 - Benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Benzene, 1,1â²-methylanebis[4... Significant New Uses for Specific Chemical Substances § 721.2535 Benzene, 1,1′-methylanebis[4-isocyanato... chemical substance identified as benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked...

40 CFR 721.2535 - Benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Benzene, 1,1â²-methylanebis[4... Significant New Uses for Specific Chemical Substances § 721.2535 Benzene, 1,1′-methylanebis[4-isocyanato... chemical substance identified as benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked...

40 CFR 721.2535 - Benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzene, 1,1â²-methylanebis[4... Significant New Uses for Specific Chemical Substances § 721.2535 Benzene, 1,1′-methylanebis[4-isocyanato... chemical substance identified as benzene, 1,1′-methylanebis[4-isocyanato-, homopolymer, Bu alc.-blocked...

47 CFR 80.385 - Frequencies for automated systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... must notify the American Radio Relay League in writing at least 30 days prior to initiation of... protection will be provided to a site-based licensee's predicted 38 dBu signal level contour. The site-based... differential. The 18 dB protection to the site-based licensee's predicted 38 dBu signal level contour shall be...

47 CFR 80.385 - Frequencies for automated systems.

Code of Federal Regulations, 2011 CFR

2011-10-01

... must notify the American Radio Relay League in writing at least 30 days prior to initiation of... protection will be provided to a site-based licensee's predicted 38 dBu signal level contour. The site-based... differential. The 18 dB protection to the site-based licensee's predicted 38 dBu signal level contour shall be...

Ureaplasma serotypes associated with the bovine urogenital tract.

PubMed Central

Truscott, R B

1983-01-01

One hundred and thirty-one ureaplasma isolates were tested using the immunoperoxidase system. Thirty-four were from semen, 34 from preputial washes of normal bulls and 63 were from vaginal swabs from herds experiencing infertility problems and/or vulvovaginitis. The serotypes from semen were T44 (12.1%), Bu2 (11.2%), D48 (2.8%), T315 (0.9%) and T288 (0.9%). Those from preputial washes were T44 (9.3%), Bu2 (8.4%), T288 (7.5%), D48 (0.9%) and T95 (0.9%). From vaginal swabs the serotypes were D48 (22.4%), Bu2 (10.3%), T45 (4.7%), T288 (3.8%) and T315 (1.9%). PMID:6365295

Building Units Design and Scale Chemistry

NASA Astrophysics Data System (ADS)

Férey, Gérard

2000-06-01

The concept of a building unit (BU) is used in two ways: the first is an a posteriori tool for description of structures which can be used to imagine new topologies originating from the description; the second one, restricted to the routes leading to the solid from the solution, starts from the reality of these building units in the solution to design new solids obtained by the tuned precipitation of these BUs with proper counterions. The room temperature and the hydrothermal routes are examined. The existence of BUs with different sizes with close topologies, revealed by numerous examples, leads us to define the notion of "scale chemistry" which concerns the edification of solids with various BUs, either organic, hybrid, or inorganic, and the consequences it has for the corresponding frameworks and the voids they generate. Not only the framework is important, and applications of the existence of large cavities are discussed. The paper ends with a discussion of the new trends which arise from this topological concept.

Synthesis and Characterization of a Series of Structurally and Electronically Diverse Fe(II) Complexes Featuring a Family of Triphenylamido-Amine Ligands

PubMed Central

Paraskevopoulou, Patrina; Ai, Lin; Wang, Qiuwen; Pinnapareddy, Devender; Acharyya, Rama; Dinda, Rupam; Das, Purak; Çelenligil-Çetin, Remle; Floros, Georgios; Sanakis, Yiannis; Choudhury, Amitava; Rath, Nigam P.; Stavropoulos, Pericles

2009-01-01

A family of triphenylamido-amine ligands of the general stoichiometry LxH3 = [R-NH-(2-C6H4)]3N (R = 4-t-BuPh (L1H3), 3,5-t-Bu2Ph (L2H3), 3,5-(CF3)2Ph (L3H3), CO-t-Bu (L4H3) 3,5-Cl2Ph (L5H3), COPh (L6H3), CO-i-Pr (L7H3), COCF3 (L8H3), i-Pr (L9H3)) has been synthesized and characterized, featuring a rigid triphenylamido-amine scaffold and an array of stereoelectronically diverse aryl, acyl and alkyl substituents (R). These ligands are deprotonated by potassium hydride in THF or DMA and reacted with anhydrous FeCl2 to afford a series of ferrous complexes, exhibiting stoichiometric variation and structural complexity. The prevalent [(Lx)Fe(II)–solv]− structures (Lx = L1, L2, L3, L5, solv = THF; Lx = L8, solv = DMA; Lx = L6, L8, solv = MeCN), reveal a distorted trigonal bipyramidal geometry, featuring ligand-derived [N3,amidoNamine] coordination and solvent attachment trans to the Namine atom. Specifically for [(L8)Fe(II)–DMA]−, an Namido residue is coordinated as the corresponding Nimino moiety (Fe–N(Ar)=C(CF3)–O−). In contrast, compounds [(L4)Fe(II)] −, [(L6)2Fe(II)2]2−, [K(L7)2Fe(II)2]22− and [K(L9)Fe]2 are all solvent-free in their coordination sphere and exhibit four-coordinate geometries of significant diversity. In particular, [(L4)Fe(II)]− demonstrates coordination of one amidato residue via the O-atom end (Fe–O–C(t-Bu)=N(Ar)). Furthermore, [(L6)2Fe(II)2]2− and [K(L7)2Fe(II)2]22− are similar structures exhibiting bridging amidato residues (Fe–N(Ar)–C(R)=O–Fe) in dimeric structural units. Finally the structure of [K(L9)Fe]2 is the only example featuring a minimal [N3,amidoNamine] coordination sphere around each Fe(II) site. All compounds have been characterized by a variety of physicochemical techniques, including Mössbauer spectroscopy and electrochemistry, to reveal electronic attributes that are responsible for a range of Fe(II)/Fe(III) redox potentials exceeding 1.0 V. PMID:19950956

Selective Bibliography in United States History Resources.

ERIC Educational Resources Information Center

Ramos, June E.; Crevling, Barbara

The selective bibliography identifies United States history materials for grades 7 through 12. It has been compiled to give teachers a representative sample of texts and supplementary materials, most of which have been published since 1975. Section one contains references to 16 basal curriculum materials. Information is given on title, author,…

Massive units deposited by bedload transport in sheet flow mode

NASA Astrophysics Data System (ADS)

Viparelli, E.; Hernandez Moreira, R. R.; Jafarinik, S.; Sanders, S.; Huffman, B.; Parker, G.; Kendall, C.

2017-12-01

A sandy massive (structureless) unit overlying a basal erosional surface and underlying a parallel or cross-laminated unit often characterizes turbidity current and coastal storm deposits. The basal massive units are thought to be the result of relatively rapid deposition of suspended sediment. However, suspension-based models fail to explain how basal massive units can be emplaced for long distances, far away from the source and can contain gravel particles as floating clasts. Here we present experimental results that can significantly change the understanding of the processes forming turbidity current and coastal storm deposits. The experiments were performed in open channel flow mode in the Hydraulics Laboratory at the University of South Carolina. The sediment was a mixture of sand size particles with a geometric mean diameter of 0.95 mm and a geometric standard deviation of 1.65. Five experiments were performed with a flow rate of 30 l/s and sediment feed rates varying between 1.5 kg/min and 20 kg/min. Each experiment was characterized by two phases, 1) the equilibration phase, in which we waited for the system to reach equilibrium condition, and 2) the aggradation phase, in which we slowly raised the water surface base level to induce channel bed aggradation under the same transport conditions observed over the equilibrium bed. Our experiments show that sandy massive units can be the result of deposition from a thick bedload layer of colliding grains, the sheet flow layer. The presence of this sheet flow layer explains how a strong, sustained current can emplace extensive massive units containing gravel clasts. Although our experiments were conducted in open-channel mode, observations of bedload driven by density underflows suggest that our results are directly applicable to sheet flows driven by deep-sea turbidity currents. More specifically, we believe that this mechanism offers an explanation for massive turbidites that heretofore have been identified as the deposits of "high density" turbidity currents.

Gonadal function and fertility after stem cell transplantation in childhood: comparison of a reduced intensity conditioning regimen containing melphalan with a myeloablative regimen containing busulfan.

PubMed

Panasiuk, Anna; Nussey, Stephen; Veys, Paul; Amrolia, Persis; Rao, Kanchan; Krawczuk-Rybak, Maryna; Leiper, Alison

2015-09-01

The occurrence of late sequelae after myeloablative conditioning regimens for stem-cell transplantation (SCT) has prompted the introduction of reduced-intensity chemotherapy (RIC) regimens in an attempt to reduce toxicity and spare fertility. We retrospectively evaluated gonadal function in survivors of SCT in childhood by comparing patients conditioned with a myeloablative regimen containing busulfan and cyclophosphamide (BuCy, N = 51, 28 boys) and a RIC regimen containing fludarabine and melphalan (FluMel, N = 40, 19 boys). Spontaneous puberty occurred in 56% of girls and 89% of boys after BuCy, whereas 90% of females and all males in the FluMel group entered puberty spontaneously (P = 0·012). Significantly more females (61%) conditioned with BuCy required hormone replacement compared with the FluMel group (10·5%, P = 0·012). Females in the FluMel group took significantly longer to develop elevation of serum follicle-stimulating hormone (FSH) concentrations (>10 iu/l) from the onset of puberty than females in the BuCy group (median 5·2 years vs. 2·7 years respectively, P = 0·0135). In males no difference was noted between the two conditioning groups in time to FSH elevation (median 4 years in FluMel versus 6 years in BuCy). Whilst the two regimens have similar effects on the testis, ovarian function seems to be better preserved in females undergoing SCT with RIC. © 2015 John Wiley & Sons Ltd.

Titanium, zinc and alkaline-earth metal complexes supported by bulky O,N,N,O-multidentate ligands: syntheses, characterisation and activity in cyclic ester polymerisation.

PubMed

Sarazin, Yann; Howard, Ruth H; Hughes, David L; Humphrey, Simon M; Bochmann, Manfred

2006-01-14

The reactions of the bulky amino-bis(phenol) ligand Me(2)NCH(2)CH(2)N[CH(2)-3,5-Bu(t)(2)-C(6)H(2)OH-2](2)(1-H(2)) with Zn[N(SiMe(3))(2)](2)(4), [Mg[N(SiMe(3))(2)](2)](2)(5) and Ca[N(SiMe(3))(2)](2)(THF)(2)(6) yield the complexes 1-Zn, 1-Mg and 1-Ca in good yields. The X-ray structure of 1-Ca showed the complex to be dimeric, with calcium in a distorted octahedral coordination geometry. Five of the positions are occupied by an N(2)O(3) donor set, while the sixth is taken up by an intramolecular close contact to an o-Bu(t) substituent, a rare case of a Ca...H-C agostic interaction (Ca...H distances of 2.37 and 2.41 Angstroms). Another sterically hindered calcium complex, Ca[2-Bu(t)-6-(C(6)F(5)N=CH)C(6)H(3)O](2)(THF)(2).(C(7)H(8))(2/3)(7), was prepared by reaction of 6 with the iminophenol 2-Bu(t)-6-(C(6)F(5)N=CH)C(6)H(3)OH (3-H). According to the crystal structure 7 is monomeric and octahedral, with trans THF ligands. The complex Ti[N[CH(2)-3-Bu(t)-5-Me-C(6)H(2)O-2](2)[CH(2)CH(2)NMe(2)

Density Functional Theory Study of the Reaction between d0 Tungsten Alkylidyne Complexes and H2O: Addition versus Hydrolysis.

PubMed

Chen, Ping; Zhang, Linxing; Xue, Zi-Ling; Wu, Yun-Dong; Zhang, Xinhao

2017-06-19

The reactions of early-transition-metal complexes with H 2 O have been investigated. An understanding of these elementary steps promotes the design of precursors for the preparation of metal oxide materials or supported heterogeneous catalysts. Density functional theory (DFT) calculations have been conducted to investigate two elementary steps of the reactions between tungsten alkylidyne complexes and H 2 O, i.e., the addition of H 2 O to the W≡C bond and ligand hydrolysis. Four tungsten alkylidyne complexes, W(≡CSiMe 3 )(CH 2 SiMe 3 ) 3 (A-1), W(≡CSiMe 3 )(CH 2 t Bu) 3 (B-1), W(≡C t Bu)(CH 2 t Bu) 3 (C-1), and W(≡C t Bu)(O t Bu) 3 (D-1), have been compared. The DFT studies provide an energy profile of the two competing pathways. An additional H 2 O molecule can serve as a proton shuttle, accelerating the H 2 O addition reaction. The effect of atoms at the α and β positions has also been examined. Because the lone-pair electrons of an O atom at the α position can interact with the orbital of the proton, the barrier of the ligand-hydrolysis reaction for D-1 is dramatically reduced. Both the electronic and steric effects of the silyl group at the β position lower the barriers of both the H 2 O addition and ligand-hydrolysis reactions. These new mechanistic findings may lead to the further development of metal complex precursors.

Human plasma kallikrein and tissue kallikrein binding to a substrate based on the reactive site of a factor Xa inhibitor isolated from Bauhinia ungulata seeds.

PubMed

Oliva, M L; Andrade, S A; Batista, I F; Sampaio, M U; Juliano, M; Fritz, H; Auerswald, E A; Sampaio, C A

1999-12-01

Kunitz type Bauhinia ungulata factor Xa inhibitor (BuXI) was purified from B. ungulata seeds. BuXI inactivates factor Xa and human plasma kallikrein (HuPK) with Ki values of 18.4 and 6.9 nM, respectively. However, Bauhinia variegata trypsin inhibitor (BvTI) which is 70% homologous to BuXI does not inhibit factor Xa and is less efficient on HuPK (Ki = 80 nM). The comparison between BuXI and BvTI reactive site structure indicates differences at Met59, Thr66 and Met67 residues. The hydrolysis rate of quenched fluorescence peptide substrates based on BuXI reactive site sequence, Abz-VMIAALPRTMFIQ-EDDnp (leading peptide), by HuPK and porcine pancreatic kallikrein (PoPK) is low, but hydrolysis is enhanced with Abz-VMIAALPRTMQ-EDDnp, derived from the leading peptide shortened by removing the dipeptide Phe-Ileu from the C-terminal portion, for HuPK (Km = 0.68 microM, k(cat)/Km = 1.3 x 10(6) M(-1) s(-1)), and the shorter substrate Abz-LPRTMQ-EDDnp is better for PoPK (Km = 0.66 microM, k(cat)/Km = 2.2 x 10(3) M(-1) s(-1)). The contribution of substrate methionine residues to HuPK and PoPK hydrolysis differs from that observed with factor Xa. The determined Km and k(cat) values suggest that the substrates interact with kallikreins the same as an enzyme and inhibitor interacts to form complexes.

Selective oxidation of benzyl alcohols to benzoic acid catalyzed by eco-friendly cobalt thioporphyrazine catalyst supported on silica-coated magnetic nanospheres.

PubMed

Li, Huan; Cao, Lan; Yang, Changjun; Zhang, Zhehui; Zhang, Bingguang; Deng, Kejian

2017-10-01

A novel magnetically recoverable thioporphyrazine catalyst (CoPz(S-Bu) 8 /SiO 2 @Fe 3 O 4 ) was prepared by immobilization of the cobalt octkis(butylthio) porphyrazine complex (CoPz(S-Bu) 8 ) on silica-coated magnetic nanospheres (SiO 2 @Fe 3 O 4 ). The composite CoPz(S-Bu) 8 /SiO 2 @Fe 3 O 4 appeared to be an active catalyst in the oxidation of benzyl alcohol in aqueous solution using hydrogen peroxide (H 2 O 2 ) as oxidant under Xe-lamp irradiation, with 36.4% conversion of benzyl alcohol, about 99% selectivity for benzoic acid and turnover number (TON) of 61.7 at ambient temperature. The biomimetic catalyst CoPz(S-Bu) 8 was supported on the magnetic carrier SiO 2 @Fe 3 O 4 so as to suspend it in aqueous solution to react with substrates, utilizing its lipophilicity. Meanwhile the CoPz(S-Bu) 8 can use its unique advantages to control the selectivity of photocatalytic oxidation without the substrate being subjected to deep oxidation. The influence of various reaction parameters on the conversion rate of benzyl alcohol and selectivity of benzoic acid was investigated in detail. Moreover, photocatalytic oxidation of substituted benzyl alcohols was obtained with high conversion and excellent selectivity, specifically conversion close to 70%, selectivity close to 100% and TON of 113.6 for para-position electron-donating groups. The selectivity and eco-friendliness of the biomimetic photocatalyst give it great potential for practical applications. Copyright © 2017. Published by Elsevier B.V.

Effects of bottom-up and top-down intervention principles in emergent literacy in children at risk of developmental dyslexia: a longitudinal study.

PubMed

Helland, Turid; Tjus, Tomas; Hovden, Marit; Ofte, Sonja; Heimann, Mikael

2011-01-01

This longitudinal study focused on the effects of two different principles of intervention in children at risk of developing dyslexia from 5 to 8 years old. The children were selected on the basis of a background questionnaire given to parents and preschool teachers, with cognitive and functional magnetic resonance imaging results substantiating group differences in neuropsychological processes associated with phonology, orthography, and phoneme-grapheme correspondence (i.e., alphabetic principle). The two principles of intervention were bottom-up (BU), "from sound to meaning", and top-down (TD), "from meaning to sound." Thus, four subgroups were established: risk/BU, risk/TD, control/BU, and control/TD. Computer-based training took place for 2 months every spring, and cognitive assessments were performed each fall of the project period. Measures of preliteracy skills for reading and spelling were phonological awareness, working memory, verbal learning, and letter knowledge. Literacy skills were assessed by word reading and spelling. At project end the control group scored significantly above age norm, whereas the risk group scored within the norm. In the at-risk group, training based on the BU principle had the strongest effects on phonological awareness and working memory scores, whereas training based on the TD principle had the strongest effects on verbal learning, letter knowledge, and literacy scores. It was concluded that appropriate, specific, data-based intervention starting in preschool can mitigate literacy impairment and that interventions should contain BU training for preliteracy skills and TD training for literacy training.

Potential of aryl-urea-benzofuranylthiazoles hybrids as multitasking agents in Alzheimer's disease.

PubMed

Kurt, Belma Zengin; Gazioglu, Isil; Basile, Livia; Sonmez, Fatih; Ginex, Tiziana; Kucukislamoglu, Mustafa; Guccione, Salvatore

2015-09-18

New benzofuranylthiazole derivatives containing the aryl-urea moiety were synthesized and evaluated in vitro as dual acetylcholinesterase (AChE)-butyrylcholinesterase (BuChE) inhibitors. In addition, the cupric reducing antioxidant capacities (CUPRAC) and ABTS cation radical scavenging abilities of the synthesized compounds were assayed. The result showed that all the synthesized compounds exhibited inhibitory activity on both AChE and BuChE with 1-(4-(5-bromobenzofuran-2-yl)thiazol-2-yl)-3-(2-fluorophenyl)urea (e25, IC50 value of 3.85 μM) and 1-(4-iodophenyl)-3-(4-(5-nitrobenzofuran-2-yl)thiazol-2-yl)urea (e38, IC50 value of 2.03 μM) as the strongest inhibitors against AChE and BuChE, respectively. Compound e38 was 8.5-fold more potent than galanthamine. The selectivity index of e25 and e38 was 2.40 and 0.37 against AChE and BuChE, respectively. Compound e2, e4 and e11 (IC50 = 0.2, 0.5 and 1.13 μM, respectively) showed a better ABTS cation radical scavenging ability than the standard quercetin (IC50 = 1.18 μM). Best poses of compounds e38 on BuChE and e25 on AChE indicate that the thiazole ring and the amidic moiety are important sites of interaction with both ChEs. In addition, the benzofuran ring and phenyl ring are anchored to the side chains of both enzymes by π-π(pi-pi) interactions. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Effect of Recombinant FVIIA in Hypothermic, Coagulopathic Pigs with Liver Injuries

DTIC Science & Technology

2005-04-01

1󈨊 190 210 230 250 Time (min) United States Army Institute of Surgical Research 33 FIG 5A. Activated Factor FVII (FVIIa) in pig plasma--as measured by...8217X18)F 18) Pre-Dilution Basal Post-Dilution Basal Experimental stage with reference to liver injury FIG 5B. Activated Factor FVII (rFVIIa...the drug, rcombinant activated Factor VII (rFVIIa) on survival, survival time, blood loss, and disseminated intravascular coagulation (DIC) in

78 FR 32374 - Magnuson-Stevens Act Provisions; General Provisions for Domestic Fisheries; Application for...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-30

...) 281-9135. FOR FURTHER INFORMATION CONTACT: Jason Berthiaume, Fishery Management Specialist, 978-281...-standard cages and 32-bu (1,703.68 L) cage tags. The traditional cages do not fit on smaller day-boats and... system, with each tag representing 32 bu (1,703.68 L) of allocation, or one cage. In addition to managing...

77 FR 72762 - Atlantic Surfclam and Ocean Quahog Fisheries; 2013 Fishing Quotas for Atlantic Surfclams and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-06

... Management Specialist, (978) 281-9177; fax (978) 281-9135. SUPPLEMENTARY INFORMATION: Section 648.72(c) of... (181 million L) for Atlantic surfclams, 5.333 million bu (284 million L) for ocean quahogs, and 100,000 Maine bu (3.524 million L) for Maine ocean quahogs, as announced in the Federal Register on December 27...

Paterno`-Bu¨chi Reaction as a Demonstration of Chemical Kinetics and Synthetic Photochemistry Using a Light Emitting Diode Apparatus

ERIC Educational Resources Information Center

Thompson, Matthew P.; Agger, Jonathan; Wong, Lu Shin

2015-01-01

The Paterno`-Bu¨chi photocycloaddition reaction is used as the basis for physical-organic final-year undergraduate laboratory experiments designed to emphasize the multidisciplinary approach to modern-day chemical practice. These reactions are performed using commercially available LED-based light sources, which offer a convenient and safe tool…

Breathing response of the tegu lizard to 1-4% CO2 in the mouth and nose or inspired into the lungs.

PubMed

Ballam, G O

1985-12-01

This study investigated the influence on ventilation of elevated CO2 in the nasal and buccal cavities (NaBuCO2) vs the effect of elevated CO2 levels inspired into the lungs (LuCO2). Separate gas sources were used to independently alter NaBuCO2 and LuCO2. As little as 1% NaBuCO2 or LuCO2 significantly increased the pause duration between the active expiratory-inspiratory cycles. Elevated NaBuCO2 caused minor changes in tidal volume, mean inspiratory and expiratory flow, and inspiratory and expiratory durations with a significant reduction in total ventilation. Elevated LuCO2 had little effect on inspiratory or expiratory durations but unlike CO2 in the upper airways, significantly increased tidal volume and mean inspiratory and expiratory flows. This study demonstrates that the increased pause duration seen in the tegu lizard to elevated environmental CO2 is due to a receptor response in the buccal or nasal cavities and also to elevated CO2 concentrations inspired into the lungs. Sensitivity of the ventilatory responses to CO2 in the upper airways is well within a physiologically relevant range.

Reactivity of a series of isostructural cobalt pincer complexes with CO2, CO, and H(+).

PubMed

Shaffer, David W; Johnson, Samantha I; Rheingold, Arnold L; Ziller, Joseph W; Goddard, William A; Nielsen, Robert J; Yang, Jenny Y

2014-12-15

The preparation and characterization of a series of isostructural cobalt complexes [Co(t-Bu)2P(E)Py(E)P(t-Bu)2(CH3CN)2][BF4]2 (Py = pyridine, E = CH2, NH, O, and X = BF4 (1a-c)) and the corresponding one-electron reduced analogues [Co(t-Bu)2P(E)Py(E)P(t-Bu)2(CH3CN)2][BF4]2 (2a-c) are reported. The reactivity of the reduced cobalt complexes with CO2, CO, and H(+) to generate intermediates in a CO2 to CO and H2O reduction cycle are described. The reduction of 1a-c and subsequent reactivity with CO2 was investigated by cyclic voltammetry, and for 1a also by infrared spectroelectrochemistry. The corresponding CO complexes of (2a-c) were prepared, and the Co-CO bond strengths were characterized by IR spectroscopy. Quantum mechanical methods (B3LYP-d3 with solvation) were used to characterize the competitive reactivity of the reduced cobalt centers with H(+) versus CO2. By investigating a series of isostructural complexes, correlations in reactivity with ligand electron withdrawing effects are made.

Tertiary amine derivatives of chlorochalcone as acetylcholinesterase (AChE) and buthylcholinesterase (BuChE) inhibitors: the influence of chlorine, alkyl amine side chain and α,β-unsaturated ketone group.

PubMed

Gao, Xiao-Hui; Zhou, Chao; Liu, Hao-Ran; Liu, Lin-Bo; Tang, Jing-Jing; Xia, Xin-Hua

2017-12-01

A new series of tertiary amine derivatives of chlorochalcone (4a∼4l) were designed, synthesized and evaluated for the effect on acetylcholinesterase (AChE) and buthylcholinesterase (BuChE). The results indicated that all compounds revealed moderate or potent inhibitory activity against AChE, and some possessed high selectivity for AChE over BuChE. The structure-activity investigation showed that the substituted position of chlorine significantly influenced the activity and selectivity. The alteration of tertiary amine group also leads to obvious change in bioactivity. Among them, IC 50 of compound 4l against AChE was 0.17 ± 0.06 µmol/L, and the selectivity was 667.2 fold for AChE over BuChE. Molecular docking and enzyme kinetic study on compound 4l suggested that it simultaneously binds to the catalytic active site (CAS) and peripheral anionic site (PAS) of AChE. Further study showed that the pyrazoline derivatives synthesized from chlorochalcones had weaker activity and lower selectivity in inhibiting AChE compared to that of chlorochalcone derivatives.

Synthesis and Characterization of Potassium Aryl- and Alkyl-Substituted Silylchalcogenolate Salts

DOE PAGES

Brown, Jessica Lynn; Montgomery, Ashley C.; Samaan, Christopher A.; ...

2016-02-23

Treatment of either triphenyl(chloro)silane or tert-butyldiphenyl(chloro)silane with potassium metal in THF, followed by addition of 18-crown-6, affords [K(18-crown-6)][SiPh 3] (1) and [K(18-crown-6)][SiPh 2 tBu] (2), respectively, as the reaction products in high yield. Compounds 1 and 2 were fully characterized including by multi-nuclear NMR and IR spectroscopies. Addition of elemental chalcogen to either 1 or 2, results in facile chalcogen insertion into the potassium-silicon bond to afford the silylchalcogenolates, [K(18-crown-6)][E– SiPh2R] (E = S, R = Ph (3); Se, R = Ph (4); E = Te, R = Ph (5); E = S, R = tBu (6); E = Se,more » R = tBu (7); E = Te, R = tBu (8)), in moderate to good yield. The silylchalcogenolates reported herein were characterized by multi-nuclear NMR and IR spectroscopies, and their solid-state molecular structures were determined by single-crystal X-ray crystallography. Importantly, the reported compounds crystallize as discrete monomers in the solid-state, a structural feature not previously observed in silylchalcogenolates, providing well-defined access routes into systematic metal complexation studies.« less

Modeling the Effects of Fire Frequency and Severity on Forests in the Northwestern United States

USGS Publications Warehouse

Busing, Richard T.; Solomon, Allen M.

2006-01-01

This study used a model of forest dynamics (FORCLIM) and actual forest survey data to demonstrate the effects of various fire regimes on different forest types in the Pacific Northwest. We examined forests in eight ecoregions ranging from wet coastal forests dominated by Pseudotsuga menziesii and other tall conifers to dry interior forests dominated by Pinus ponderosa. Fire effects simulated as elevated mortality of trees based on their species and size did alter forest structure and species composition. Low frequency fires characteristic of wetter forests (return interval >200 yr) had minor effects on composition. When fires were severe, they tended to reduce total basal area with little regard to species differences. High frequency fires characteristic of drier forests (return interval <30 yr) had major effects on species composition and on total basal area. Typically, they caused substantial reductions in total basal area and shifts in dominance toward highly fire tolerant species. With the addition of fire, simulated basal areas averaged across ecoregions were reduced to levels approximating observed basal areas.

Late Proterozoic glacially controlled shelf sequences in western Mali (west Africa)

NASA Astrophysics Data System (ADS)

Deynoux, M.; Prousti, J. N.; Simon, B.

The Late Proterozoic deposits of the Bakoye Group (500 m) in western Mali constitute a remarkable example of a glacially influenced sedimentary record on an epicratonic platform. They are composed of alternating marine and continental formations which represent accumulation in a basin located in the vicinity of upland areas covered by ice sheets. One of these formations (the Ba4 Formation), which is the focus of this study, is composed of three major units. The basal Unit 1 is made up of carbonaceous coarse to fine grained sandstones which are organized in fining upward sequences and which comprise lenticular diamictite intercalations. This Unit is considered to represent the fore slope gravity flows of a subaqueous ice-cootact fan fed by meltwater streams (≪glacioturbidites≫). Unit 2 is made up of coarse to fine grained sandstones in a highly variable association of facies. This Unit is characterized by the abundance of wave ripples associated with convolute beddings. planar or wavy beddings and tabular or hummocky crossbeddings in a general shallowing upward trend. It also comprises evidence of gravity processes including debris flows and large slumped sandstone bodies. Unit 2 represents the progressive filling of the Ba4 basin and reflects the combined effect of glacially induced eustatism and isostacy during a phase of glacial retreat. The basal part of Unit 3 is made up of a succession (a few meters thick) of conglomerates, diamictites, sandstones, siltstones or carbonates lying on an erosional unconformity marked by periglacial frost wedges. The upper part of Unit 3 is thicker (100-150 m) and onlaps on these basal facies with a succession of sandstone bars exhibiting swaley and hummocky crossbeddings, large cut and fill structures, and planar laminations. Unit 3 is strongly transgressive, the lower shoreface and backshore deposits include algal mats and are onlapped by sand ridges emplaced in a high energy upper to middle shoreface environment. Overall, in tems of sequential stratigraphy, the deposits of the galcial Bakoya Groupe are organized in shallowing upward sequences limited by maximum flooding surfaces of regional extent. One of these sequences (the Ba4 Formation) is subdivided into parasequences generated in relation with local ice sheet fluctuation including glacioisostacy.

The Surface Chemistry of Metal Chalcogenide Nanocrystals

NASA Astrophysics Data System (ADS)

Anderson, Nicholas Charles

The surface chemistry of metal chalcogenide nanocrystals is explored through several interrelated analytical investigations. After a brief discussion of the nanocrystal history and applications, molecular orbital theory is used to describe the electronic properties of semiconductors, and how these materials behave on the nanoscale. Quantum confinement plays a major role in dictating the optical properties of metal chalcogenide nanocrystals, however surface states also have an equally significant contribution to the electronic properties of nanocrystals due to the high surface area to volume ratio of nanoscale semiconductors. Controlling surface chemistry is essential to functionalizing these materials for biological imaging and photovoltaic device applications. To better understand the surface chemistry of semiconducting nanocrystals, three competing surface chemistry models are presented: 1.) The TOPO model, 2.) the Non-stoichiometric model, and 3.) the Neutral Fragment model. Both the non-stoichiometric and neutral fragment models accurately describe the behavior of metal chalcogenide nanocrystals. These models rely on the covalent bond classification system, which divides ligands into three classes: 1.) X-type, 1-electron donating ligands that balance charge with excess metal at the nanocrystal surface, 2.) L-type, 2-electron donors that bind metal sites, and 3.) Z-type, 2-electron acceptors that bind chalcogenide sites. Each of these ligand classes is explored in detail to better understand the surface chemistry of metal chalcogenide nanocrystals. First, chloride-terminated, tri-n-butylphosphine (Bu 3P) bound CdSe nanocrystals were prepared by cleaving carboxylate ligands from CdSe nanocrystals with chlorotrimethylsilane in Bu3P solution. 1H and 31P{1H} nuclear magnetic resonance spectra of the isolated nanocrystals allowed assignment of distinct signals from several free and bound species, including surface-bound Bu3P and [Bu3P-H]+[Cl]- ligands as well as a Bu3P complex of cadmium chloride. Nuclear magnetic resonance spectroscopy supports complete cleavage of the X-type carboxylate ligands. Combined with measurements of the Se:Cd:Cl ratio using Rutherford backscattering spectrometry, these studies support a structural model of nanocrystals where chloride ligands terminate the crystal lattice by balancing the charges of excess Cd2+ ions. The adsorption of dative phosphine ligands leads to nanocrystals who's solubility is afforded by reversibly bound and readily exchanged L-type ligands, e.g. primary amines and phosphines. The other halides (Br and I) can also be used to prepare Bu 3P-bound, halide-terminated CdSe nanocrystals, however these nanocrystals are not soluble after exchange. The change in binding affinity of Bu 3P over the halide series is briefly discussed. Next, we report a series of L-type ligand exchanges using Bu3P-bound, chloride-terminated CdSe nanocrystals with several Lewis bases, including aromatic, cyclic, and non-cyclic sulfides, and ethers; primary, secondary, and tertiary amines and phosphines; tertiary phosphine chalcogenides; primary alcohols, isocyanides, and isothiocyanides. Using 31P nuclear magnetic resonance spectroscopy, we establish a relative binding affinity for these ligands that reflects electronic considerations but is dominated primarily by steric interactions, as determined by comparing binding affinity to Tolmann cone angles. We also used chloride-terminated CdSe nanocrystals to explore the reactivity of ionic salts at nanocrystal surfaces. These salts, particularly [Bu3P-H]+[Cl]-, bind nanocrystals surfaces as L-type ligands, making them soluble in polar solvents such as acetonitrile. This information should provide insight for rational ligand design for future applications involving metal chalcogenide nanocrystals. The strongest ligand, primary n-alkylamine, rapidly displace the Bu3P from halide-terminated CdSe nanocrystals, leading to amine-bound nanocrystals with higher dative ligand coverages and greatly increased photoluminescence quantum yields. The importance of ligand coverage to both the UV-visible absorption and photoluminescence spectra are discussed. (Abstract shortened by UMI.).

Contribution of the 2(1)Ag state to the third-order optical nonlinearity in a squaraine dye.

PubMed

Andrews, J H; Khaydarov, J D; Singer, K D

1994-07-01

We have measured the third-harmonic response, gamma, of a centrosymmetric squaraine dye (ISQ) in chloroform at a range of frequencies for which the third harmonic is above the strong, narrow peak in the dye's linear absorption spectrum but below the UV absorption band. By fitting the experimental dispersion of gamma using a four-level model, we determine the strength, location, and width of the lowest-lying two-photon transition. We find that the 2(1)Ag state appears just above the 1(1)Bu state in energy and that the 1(1)Bu-2(1)Ag transition moment is somewhat smaller than the transition moment between the ground state and the 1(1)Bu state but much larger than previously predicted for comparable squaraine dyes.

Luminescent silver(I) tert-butylethynide compounds with nicotinic/isonicotinic acid as ligands

NASA Astrophysics Data System (ADS)

Xie, Yi-Ming; Fan, Yue-Yue; Lin, Fu-Lin; Hu, Ting; Liu, Jia; Lu, Can-Zhong

2017-12-01

Solvothermal reaction of tBuC≡CAg, AgBF4 and nicotinic/isonicotinic acid in acetonitrile afforded two new silver(I) tert-butylethynide double salts, namely [(tBuC≡CAg)(AgL1)3] (HL1 = nicotinic acid) (1) and [(tBuC≡CAg)(AgL1)2] (HL2 = isonicotinic acid) (2). These compounds have been characterized by elemental analysis, infrared spectra, single-crystal X-ray analysis, X-ray powder diffraction, thermogravimetric analysis, UV-visible absorption spectra, and luminescent measurement. 1 exhibits a two-dimensional coordination network, and 2 features a three-dimensional coordination architecture. Luminescence measurements indicate that 1 shows a fluorescent emission band centered at 568 nm, and 2 exhibits an intense emission maximum at 550 nm and a shoulder peak at 436 nm.

Attenuation of dermal wounds via downregulating oxidative stress and inflammatory markers by protocatechuic acid rich n-butanol fraction of Trianthema portulacastrum Linn. in wistar albino rats.

PubMed

Yadav, Ekta; Singh, Deepika; Yadav, Pankajkumar; Verma, Amita

2017-12-01

Oxidative stress and inflammation contribute as a key factor for retarding the process of dermal wound healing. Trianthema portulcastrum Linn. (TP) leaves reported to possess antioxidant, antifungal, anti-inflammatory and antibacterial properties, which could make TP a promising wound healing agent. The current study was aimed to estimate the antioxidant potential of the fractionated hydroethanolic extract of TP leaves and evaluate wound healing activity by excision and incision wound models along with the assessment of possible underlying mechanism. Ethyl acetate, chloroform and n-butanol fractions of the hydroethanolic extract of TP leaves were examined for in vitro antioxidant ability by DPPH method. Strongest antioxidant activity bearing n-butanol fraction (nBuTP) was further analyzed quantitatively by High Performance Liquid Chromatography coupled with Diode Array Detector (HPLC-DAD). Wound healing potential of nBUTP using excision and incision wound model was studied. Wistar albino rats were randomly divided into four groups, containing six animals in each group; group I served as control treated with simple ointment base, group II was standard group, treated with povidone-iodine ointment USP (5%), group III treated with nBuTP 5% w/w ointment, and group IV treated with nBuTP 10%w/w ointment. All the groups were topically applied their respective ointments, once daily, till the complete healing achieved. Wound healing was assessed by analyzing % wound closure, hydroxyproline content, epithelialization period, tensile strength, enzymatic antioxidative status and inflammatory markers. Total phenolic and flavonoid content of the extract was estimated to be 112.32±1.12 and 84.42±0.47mg/g, respectively. HPLC-DAD of nBuTP confirmed the presence of chlorogenic acid (20.74±0.03), protocatechuic acid (34.45±0.02mg/g), caffeic acid (4.31±0.03mg/g) and ferulic acid (1.43±0.01mg/g). 5% and 10%w/w nBuTP ointment significantly accelerated the wound healing process dose-dependently in both wound models, evidenced by the faster rate of wound contraction, epithelialization, increased hydroxyproline content, high tensile strength, increased antioxidant enzyme activity, decreased the level of inflammatory markers compared to the control group. Histopathological studies also revealed the dose-dependant amelioration of wound healing by re-epithelialization, collagenation and vascularization of wounded skin sample in nBuTP treated groups. These results implicate potential medicinal value of nBuTP to heal dermal wounds. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Geochemical Models of Water-Quality Changes During Aquifer Storage Recovery (ASR) Cycle Tests, Phase 1: Geochemical Models Using Existing Data

DTIC Science & Technology

2006-09-01

Richardson, in review). Figure 1 shows the lithostratigraphic setting for Eocene through Miocene strata, and the occurrence of hydrostratigraphic units of...basal Haw- thorn unit lies unconformably on lithologies informally called “ Eocene limestones,” which consist of Suwannee Limestone, Ocala Limestone

Accessing conjugated polymers with precisely controlled heterobisfunctional chain ends via post-polymerization modification of the OTf group and controlled Pd(0)/t-Bu 3P-catalyzed Suzuki cross-coupling polymerization

DOE PAGES

Hu, Qiao -Sheng; Hong, Kunlun; Zhang, Hong -Hai

2015-08-12

In this study, a general strategy toward the synthesis of well-defined conjugated polymers with controlled heterobisfunctional chain ends via combination of controlled Pd(0)/t-Bu 3P Suzuki cross-coupling polymerization with the post-polymerization modification of the triflate (OTf) group was disclosed.

Biotransformation of Tin.

DTIC Science & Technology

1981-05-26

of tributyltin moiety, Bu3Sn’ ( TBT ). rBT-resistant organisms from the Chesapeake. Bay were found to accumulate tributyltin . This accumulation did not...biotrans- formations of tributyltin moiety, Bu3Sn+ ( TBT ). TBT -resistant organisms chraz: from the Chesapeake Bay were found to accumulate tributyltin ...experiments (ref.l1). TRIBUTYLTIN DEGRADATION STUDIES As tribut,.ltin cation ( TBT ) is one of the most active biocidal agents extensively incorporated in

Accessing conjugated polymers with precisely controlled heterobisfunctional chain ends via post-polymerization modification of the OTf group and controlled Pd(0)/t-Bu 3P-catalyzed Suzuki cross-coupling polymerization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Qiao -Sheng; Hong, Kunlun; Zhang, Hong -Hai

In this study, a general strategy toward the synthesis of well-defined conjugated polymers with controlled heterobisfunctional chain ends via combination of controlled Pd(0)/t-Bu 3P Suzuki cross-coupling polymerization with the post-polymerization modification of the triflate (OTf) group was disclosed.

SPPS of protected peptidyl aminoalkyl amides.

PubMed

Karavoltsos, Manolis; Mourtas, Spyros; Gatos, Dimitrios; Barlos, Kleomenis

2002-11-01

Monophthaloyl diamines derived from naturally occurring amino acids were attached through their free amino functions to resins of the trityl type. The phthaloyl groups were removed by hydrazinolysis, and peptide chains were assembled using Fmoc/tBu-amino acids on the liberated amino functions. The peptidyl aminoalkyl amides obtained were cleaved from the resins by mild acidolysis, with the tBu-side chain protection remaining intact.

7 CFR 1412.53 - Counter-cyclical payment provisions.

Code of Federal Regulations, 2013 CFR

2013-01-01

...) Oats—$1.33/bu. (F) Upland cotton—$0.52/lb. (G) Long grain rice—$6.50/cwt. (H) Medium grain rice—$6.50/cwt. (I) Soybeans—$5.00/bu. (J) Other oilseeds—$9.30/cwt. (K) Dry Peas—$5.40/cwt. (2009 crop only). (L) Lentils—$11.28/cwt. (2009 crop only). (M) Small Chickpeas—$7.43/cwt. (2009 crop only). (N) Large Chickpeas...

7 CFR 1412.53 - Counter-cyclical payment provisions.

Code of Federal Regulations, 2012 CFR

2012-01-01

...) Oats—$1.33/bu. (F) Upland cotton—$0.52/lb. (G) Long grain rice—$6.50/cwt. (H) Medium grain rice—$6.50/cwt. (I) Soybeans—$5.00/bu. (J) Other oilseeds—$9.30/cwt. (K) Dry Peas—$5.40/cwt. (2009 crop only). (L) Lentils—$11.28/cwt. (2009 crop only). (M) Small Chickpeas—$7.43/cwt. (2009 crop only). (N) Large Chickpeas...

7 CFR 1412.53 - Counter-cyclical payment provisions.

Code of Federal Regulations, 2014 CFR

2014-01-01

...) Oats—$1.33/bu. (F) Upland cotton—$0.52/lb. (G) Long grain rice—$6.50/cwt. (H) Medium grain rice—$6.50/cwt. (I) Soybeans—$5.00/bu. (J) Other oilseeds—$9.30/cwt. (K) Dry Peas—$5.40/cwt. (2009 crop only). (L) Lentils—$11.28/cwt. (2009 crop only). (M) Small Chickpeas—$7.43/cwt. (2009 crop only). (N) Large Chickpeas...

7 CFR 1412.53 - Counter-cyclical payment provisions.

Code of Federal Regulations, 2011 CFR

2011-01-01

...) Oats—$1.33/bu. (F) Upland cotton—$0.52/lb. (G) Long grain rice—$6.50/cwt. (H) Medium grain rice—$6.50/cwt. (I) Soybeans—$5.00/bu. (J) Other oilseeds—$9.30/cwt. (K) Dry Peas—$5.40/cwt. (2009 crop only). (L) Lentils—$11.28/cwt. (2009 crop only). (M) Small Chickpeas—$7.43/cwt. (2009 crop only). (N) Large Chickpeas...

Basal C-peptide Level as a Surrogate Marker of Subclinical Atherosclerosis in Type 2 Diabetic Patients

PubMed Central

Kim, Sung-Tae; Kim, Byung-Joon; Song, In-Geol; Jung, Jang-Han; Lee, Kang-Woo; Park, Keun-Young; Cho, Youn-Zoo; Lee, Dae-Ho; Koh, Gwan-Pyo

2011-01-01

Background Recent studies have revealed that C-peptide induces smooth muscle cell proliferation and causes human atherosclerotic lesions in diabetic patients. The present study was designed to examine whether the basal C-peptide levels correlate with cardiovascular risk in type 2 diabetes mellitus (T2DM) patients. Methods Data was obtained from 467 patients with T2DM from two institutions who were followed for four years. The medical findings of all patients were reviewed, and patients with creatinine >1.4 mg/dL, any inflammation or infection, hepatitis, or type 1 DM were excluded. The relationships between basal C-peptide and other clinical values were statistically analyzed. Results A simple correlation was found between basal C-peptide and components of metabolic syndrome (MS). Statistically basal C-peptide levels were significantly higher than the three different MS criteria used in the present study, the Adult Treatment Panel III (ATP III) of the National Cholesterol Education Program's (NCEP's), World Health Organization (WHO), and the International Diabetes Federation (IDF) criteria (NCEP-ATP III, P=0.001; IDF, P<0.001; WHO, P=0.029). The multiple regression analysis between intima-media thickness (IMT) and clinical values showed that basal C-peptide significantly correlated with IMT (P=0.043), while the analysis between the 10-year coronary heart disease risk by the United Kingdom Prospective Diabetes Study risk engine and clinical values showed that basal C-peptide did not correlate with IMT (P=0.226). Conclusion Basal C-peptide is related to cardiovascular predictors (IMT) of T2DM, suggesting that basal C-peptide does provide a further indication of cardiovascular disease. PMID:21537412

Management of Mucosal Basal Cell Carcinoma of the Lip: An Update and Comprehensive Review of the Literature.

PubMed

Loh, Tiffany; Rubin, Ashley G; Brian Jiang, Shang I

2016-12-01

Basal cell carcinoma (BCC) is the most common malignancy in the United States. Most BCCs occur on cutaneous surfaces, but rare cases on the mucosal lip have also been documented. Because only a small number of mucosal BCC (mBCC) cases have been reported, data on their clinical characteristics and management are limited. To perform an updated literature review of the management of mBCCs on the lip. A comprehensive literature review was conducted through a search of the PubMed database with the key phrases "mucosal basal cell carcinoma," "basal cell carcinoma mucosa," and "basal cell carcinoma lip mucosa." Forty-eight cases of mBCCs have been reported, and 35 had sufficient data for analysis. The average age at presentation was 66.8 years, and 57% (n = 20) had a history of skin cancer. Most cases were treated with surgical excision or Mohs micrographic surgery (MMS), with only 1 recurrence in the literature. Furthermore, the authors present 8 additional cases of mBCCs successfully treated with MMS. Mucosal basal cell carcinomas are rare, and skin cancer history may be a risk factor. Because the lip is a cosmetically and functionally important area, MMS may be the preferred treatment method for mBCCs in this location.

Benchmarking Insulin Treatment Persistence Among Patients with Type 2 Diabetes Across Different U.S. Payer Segments.

PubMed

Wei, Wenhui; Jiang, Jenny; Lou, Youbei; Ganguli, Sohini; Matusik, Mark S

2017-03-01

Treatment persistence with basal insulins is crucial to achieving sustained glycemic control, which is associated with a reduced risk of microvascular disease and other complications of type 2 diabetes (T2D). However, studies suggest that persistence with basal insulin treatment is often poor. To measure and benchmark real-world basal insulin treatment persistence among patients with T2D across different payer segments in the United States. This was a retrospective observational study of data from a national pharmacy database (Walgreen Co., Deerfield, IL). The analysis included patients with T2D aged ≥ 18 years who filled ≥ 1 prescription for basal insulins between January 2013 and June 2013 (the index prescription) and who had also filled prescriptions for ≥ 1 oral antidiabetes drug in the database. Patients with claims for premixed insulin were excluded. Treatment persistence was defined as remaining on the study medication(s) during the 1-year follow-up period. Patients were stratified according to treatment history (existing basal insulin users vs. new insulin users), payer segments (commercially insured, Medicare, Medicaid, or cash-pay), type of basal insulin (insulin glargine, insulin detemir, or neutral protamine Hagedorn insulin [NPH]), and device for insulin administration (pen or vial/syringe). A total of 274,102 patients were included in this analysis, 82% of whom were existing insulin users. In terms of payer segments, 45.3% of patients were commercially insured, 47.8% had Medicare, 5.9% had Medicaid, and 1.1% were cash-pay. At the 1-year follow-up, basal insulin treatment persistence rate was 66.8% overall, 61.7% for new users, and 67.9% for existing users. In general, for both existing and new basal insulin users, higher persistence rate and duration were associated with Medicare versus cash-pay patients, use of insulin pens versus vial/syringe, and use of insulin glargine versus NPH. This large-scale study provides a benchmark of basal insulin treatment persistence across different payers in the United States. Findings indicate that basal insulin persistence patterns are significantly different across different payers, basal insulin types, and devices. This information may be useful in developing targeted approaches to improve T2D patients' persistence with insulin treatment for better glycemic control. This study was funded by Sanofi U.S. through a grant provided to Walgreens for research services. Matusik, Jiang, and Lou are employed by Walgreen Co. Wei and Ganguli were employed by Sanofi U.S. at the time of this study. Study concept and design were contributed by Wei, Ganguli, and Matusik, with assistance from Lou. Jiang took the lead in data collection, along with Lou, and data interpretation was performed by Wei, Lou, and Jiang, along with Ganguli and Matusik. The manuscript was written by Wei and Jiang, along with Ganguli and Matusik, and revised by Wei and Ganguli, along with the other authors.

Contribution of the community health volunteers in the control of Buruli ulcer in Bénin.

PubMed

Barogui, Yves Thierry; Sopoh, Ghislain Emmanuel; Johnson, Roch Christian; de Zeeuw, Janine; Dossou, Ange Dodji; Houezo, Jean Gabin; Chauty, Annick; Aguiar, Julia; Agossadou, Didier; Edorh, Patrick A; Asiedu, Kingsley; van der Werf, Tjip S; Stienstra, Ymkje

2014-10-01

Buruli ulcer (BU) is a neglected tropical disease caused by Mycobacterium ulcerans. Usually BU begins as a painless nodule, plaque or edema, ultimately developing into an ulcer. The high number of patients presenting with ulcers in an advanced stage is striking. Such late presentation will complicate treatment and have long-term disabilities as a consequence. The disease is mainly endemic in West Africa. The primary strategy for control of this disease is early detection using community village volunteers. In this retrospective, observational study, information regarding Buruli ulcer patients that reported to one of the four BU centers in Bénin between January 2008 and December 2010 was collected using the WHO/BU01 forms. Information used from these forms included general characteristics of the patient, the results of diagnostic tests, the presence of functional limitations at start of treatment, lesion size, patient delay and the referral system. The role of the different referral systems on the stage of disease at presentation in the hospital was analyzed by a logistic regression analysis. About a quarter of the patients (26.5%) were referred to the hospital by the community health volunteers. In our data set, patients referred to the hospital by community health volunteers appeared to be in an earlier stage of disease than patients referred by other methods, but after adjustment by the regression analysis for the health center, this effect could no longer be seen. The Polymerase Chain Reaction (PCR) for IS2404 positivity rate among patients referred by the community health volunteers was not systematically lower than in patients referred by other systems. This study clarifies the role played by community health volunteers in Bénin, and shows that they play an important role in the control of BU.

Potentiation of oxycodone antinociception in mice by agmatine and BMS182874 via an imidazoline I2 receptor-mediated mechanism.

PubMed

Bhalla, Shaifali; Ali, Izna; Lee, Hyaera; Andurkar, Shridhar V; Gulati, Anil

2013-01-01

The potentiation of oxycodone antinociception by BMS182874 (endothelin-A (ET(A)) receptor antagonist) and agmatine (imidazoline receptor/α(2)-adrenoceptor agonist) is well-documented. It is also known that imidazoline receptors but not α(2)-adrenoceptors are involved in potentiation of oxycodone antinociception by agmatine and BMS182874 in mice. However, the involvement of specific imidazoline receptor subtypes (I(1), I(2), or both) in this interaction is not clearly understood. The present study was conducted to determine the involvement of imidazoline I(1) and I(2) receptors in agmatine- and BMS182874-induced potentiation of oxycodone antinociception in mice. Antinociceptive (tail flick and hot-plate) latencies were determined in male Swiss Webster mice treated with oxycodone, agmatine, BMS182874, and combined administration of oxycodone with agmatine or BMS182874. Efaroxan (imidazoline I(1) receptor antagonist) and BU224 (imidazoline I(2) receptor antagonist) were used to determine the involvement of I(1) and I(2) imidazoline receptors, respectively. Oxycodone produced significant antinociceptive response in mice which was not affected by efaroxan but was blocked by BU224. Agmatine-induced potentiation of oxycodone antinociception was blocked by BU224 but not by efaroxan. Similarly, BMS182874-induced potentiation of oxycodone antinociception was blocked by BU224 but not by efaroxan. This is the first report demonstrating that BMS182874- or agmatine-induced enhancement of oxycodone antinociception is blocked by BU224 but not by efaroxan. We conclude that imidazoline I(2) receptors but not imidazoline I(1) receptors are involved in BMS182874- and agmatine-induced potentiation of oxycodone antinociception in mice. Copyright © 2012 Elsevier Inc. All rights reserved.

Molecular Modeling on Berberine Derivatives toward BuChE: An Integrated Study with Quantitative Structure-Activity Relationships Models, Molecular Docking, and Molecular Dynamics Simulations.

PubMed

Fang, Jiansong; Pang, Xiaocong; Wu, Ping; Yan, Rong; Gao, Li; Li, Chao; Lian, Wenwen; Wang, Qi; Liu, Ai-lin; Du, Guan-hua

2016-05-01

A dataset of 67 berberine derivatives for the inhibition of butyrylcholinesterase (BuChE) was studied based on the combination of quantitative structure-activity relationships models, molecular docking, and molecular dynamics methods. First, a series of berberine derivatives were reported, and their inhibitory activities toward butyrylcholinesterase (BuChE) were evaluated. By 2D- quantitative structure-activity relationships studies, the best model built by partial least-square had a conventional correlation coefficient of the training set (R(2)) of 0.883, a cross-validation correlation coefficient (Qcv2) of 0.777, and a conventional correlation coefficient of the test set (Rpred2) of 0.775. The model was also confirmed by Y-randomization examination. In addition, the molecular docking and molecular dynamics simulation were performed to better elucidate the inhibitory mechanism of three typical berberine derivatives (berberine, C2, and C55) toward BuChE. The predicted binding free energy results were consistent with the experimental data and showed that the van der Waals energy term (ΔEvdw) difference played the most important role in differentiating the activity among the three inhibitors (berberine, C2, and C55). The developed quantitative structure-activity relationships models provide details on the fine relationship linking structure and activity and offer clues for structural modifications, and the molecular simulation helps to understand the inhibitory mechanism of the three typical inhibitors. In conclusion, the results of this study provide useful clues for new drug design and discovery of BuChE inhibitors from berberine derivatives. © 2015 John Wiley & Sons A/S.

Synthesis and evaluation of an 18 F-labeled trifluoroborate derivative of 2-nitroimidazole for imaging tumor hypoxia with positron emission tomography.

PubMed

Nunes, Paulo Sérgio Gonçalves; Zhang, Zhengxing; Kuo, Hsiou-Ting; Zhang, Chengcheng; Rousseau, Julie; Rousseau, Etienne; Lau, Joseph; Kwon, Daniel; Carvalho, Ivone; Bénard, François; Lin, Kuo-Shyan

2018-04-01

2-Nitroimidazole-based hypoxia imaging tracers such as 18 F-FMISO are normally imaged at late time points (several hours post-injection) due to their slow clearance from background tissues. Here, we investigated if a hydrophilic zwitterion-based ammoniomethyl-trifluoroborate derivative of 2-nitroimidazole, 18 F-AmBF 3 -Bu-2NI, could have the potential to image tumor hypoxia at earlier time points. AmBF 3 -Bu-2NI was prepared in 4 steps. 18 F labeling was conducted via 18 F- 19 F isotope exchange reaction, and 18 F-AmBF 3 -Bu-2NI was obtained in 14.8 ± 0.4% (n = 3) decay-corrected radiochemical yield with 24.5 ± 5.2 GBq/μmol specific activity and >99% radiochemical purity. Imaging and biodistribution studies in HT-29 tumor-bearing mice showed that 18 F-AmBF 3 -Bu-2NI cleared quickly from blood and was excreted via the hepatobiliary and renal pathways. However, the tumor was not visualized in PET images until 3 hours post-injection due to low tumor uptake (0.54 ± 0.13 and 0.19 ± 0.04%ID/g at 1 and 3 hours post-injection, respectively). The low tumor uptake is likely due to the highly hydrophilic motif of ammoniomethyl-trifluoroborate that prevents free diffusion of 18 F-AmBF 3 -Bu-2NI across the cell membrane. Our results suggest that highly hydrophilic 18 F-labeled ammoniomethyl-trifluoroborate derivatives might not be suitable for imaging intracellular targets including nitroreductase, a common tumor hypoxia imaging target. Copyright © 2017 John Wiley & Sons, Ltd.

Multiscale Assessment of Listed and At-Risk Species’ Climate Change Vulnerabilities

DTIC Science & Technology

2017-07-15

Anthropogenically altered landscapes (e.g., urban or agricultural areas) that may hinder the dispersal of a species. B3. Land Use Changes from Climate Change...vulnerable (HV) and ex- tremely vulnerable (EV). Federal land management agencies include: Agricultural Research Service (ARS), Bu- reau of Land...agencies include: Agricultural Research Service (ARS), Bu- reau of Land Management (BLM), Bureau of Reclamation (BOR), Department of Defense (DoD

Rheological Behavior of Entangled Polystyrene-Polyhedral Oligosilsesquioxane (POSS) Copolymer

DTIC Science & Technology

2006-08-24

analysis. The effects of the presence of tethered POSS cages on the glass transition were studied using differential scanning...studies mainly focused on the effect of the long chain branches (LCBs) on the linear and non- linear rheological properties. How spherical cage -like...apparent activation energy increasing with increasing iBuPOSS loading. Like linear polymeric coil branches, the iBuPOSS cage plays a negative effect on

A MURI Center for Intelligent Biomimetic Image Processing and Classification

DTIC Science & Technology

2007-11-01

Grossberg, S., Editor of a new journal on Current Opinion in Cognitive Neurodynamics , 2005. 34. Grossberg, S., Editor of the new International...Department of Cognitive and Neural Systems 677 Beacon Street Boston MA 02215 steve(&bu.edu Phone: 617-353-7857 Fax: 617-353-7755 http://cns.bu.edu...memory, learning of sequential plans, and sequence performance during cognitive information processing; (8) coordinated ballistic and smooth pursuit

Beth-Uhlenbeck approach for repulsive interactions between baryons in a hadron gas

NASA Astrophysics Data System (ADS)

Vovchenko, Volodymyr; Motornenko, Anton; Gorenstein, Mark I.; Stoecker, Horst

2018-03-01

The quantum mechanical Beth-Uhlenbeck (BU) approach for repulsive hard-core interactions between baryons is applied to the thermodynamics of a hadron gas. The second virial coefficient a2—the "excluded volume" parameter—calculated within the BU approach is found to be temperature dependent, and it differs dramatically from the classical excluded volume (EV) model result. At temperatures T =100 -200 MeV, the widely used classical EV model underestimates the EV parameter for nucleons at a given value of the nucleon hard-core radius by large factors of 3-4. Previous studies, which employed the hard-core radii of hadrons as an input into the classical EV model, have to be re-evaluated using the appropriately rescaled EV parameters. The BU approach is used to model the repulsive baryonic interactions in the hadron resonance gas (HRG) model. Lattice data for the second- and fourth-order net baryon susceptibilities are described fairly well when the temperature dependent BU baryonic excluded volume parameter corresponds to nucleon hard-core radii of rc=0.25 -0.3 fm. Role of the attractive baryonic interactions is also considered. It is argued that HRG model with a constant baryon-baryon EV parameter vN N≃1 fm3 provides a simple yet efficient description of baryon-baryon interaction in the crossover temperature region.

An efficient copper phthalocyanine additive of perovskite precursor for improving the photovoltaic performance of planar perovskite solar cells

NASA Astrophysics Data System (ADS)

Wu, Shufang; Liu, Qingwei; Zheng, Ya; Li, Renjie; Peng, Tianyou

2017-08-01

Solution processable planar heterojunction perovskite solar cell has drawn much attention as a promising low-cost photovoltaic device, and much effort has been made to improve its power conversion efficiency by choosing appropriate additives for the perovskite precursor solution. Different to those additives reported, a soluble and thermal stable tert-butyl substituted copper phthalocyanine (CuPc(tBu)4) as additive is first introduced into the perovskite precursor solution of a planar perovskite solar cell that is fabricated via the one-step solution process. It is found that the pristine device without CuPc(tBu)4 additive exhibits a power conversion efficiency of 15.3%, while an extremely low concentration (4.4 × 10-3 mM) of CuPc(tBu)4 in the precursor solution leads to the corresponding device achieving an enhanced power conversion efficiency of 17.3%. CuPc(tBu)4 as an additive can improve the quality of perovskite layer with higher crystallinity and surface coverage, then resulting in enhanced light absorption and reduced charge recombination, and thus the better power conversion efficiency. The finding presented here provides a new choice for improving the quality of perovskite layer and the photovoltaic performance of the planar heterojunction perovskite solar cells.

Dual inhibition of acetylcholinesterase and butyrylcholinesterase enzymes by allicin

PubMed Central

Kumar, Suresh

2015-01-01

Objectives: The brain of mammals contains two major form of cholinesterase enzymes, acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). The dual inhibition of these enzymes is considered as a promising strategy for the treatment of neurological disorder such as Alzheimer's disease (AD), senile dementia, ataxia, and myasthenia gravis. The present study was undertaken to explore the anticholinesterase inhibition property of allicin. Materials and Methods: An assessment of cholinesterase inhibition was carried out by Ellman's assay. Results: The present study demonstrates allicin, a major ingredient of crushed garlic (Allium sativum L.) inhibited both AChE and BuChE enzymes in a concentration-dependent manner. For allicin, the IC50 concentration was 0.01 mg/mL (61.62 μM) for AChE and 0.05 ± 0.018 mg/mL (308.12 μM) for BuChE enzymes. Conclusions: Allicin shows a potential to ameliorate the decline of cognitive function and memory loss associated with AD by inhibiting cholinesterase enzymes and upregulate the levels of acetylcholine (ACh) in the brain. It can be used as a new lead to target AChE and BuChE to upregulate the level of ACh which will be useful in alleviating the symptoms associated with AD. PMID:26288480

Bioinspired Design and Computational Prediction of Iron Complexes with Pendant Amines for the Production of Methanol from CO2 and H2.

PubMed

Chen, Xiangyang; Yang, Xinzheng

2016-03-17

Inspired by the active site structure of [FeFe]-hydrogenase, we built a series of iron dicarbonyl diphosphine complexes with pendant amines and predicted their potentials to catalyze the hydrogenation of CO2 to methanol using density functional theory. Among the proposed iron complexes, [(P(tBu)2N(tBu)2H)FeH(CO)2(COOH)](+) (5COOH) is the most active one with a total free energy barrier of 23.7 kcal/mol. Such a low barrier indicates that 5COOH is a very promising low-cost catalyst for high-efficiency conversion of CO2 and H2 to methanol under mild conditions. For comparison, we also examined Bullock's Cp iron diphosphine complex with pendant amines, [(P(tBu)2N(tBu)2H)FeHCp(C5F4N)](+) (5Cp-C5F4N), as a catalyst for hydrogenation of CO2 to methanol and obtained a total free energy barrier of 27.6 kcal/mol, which indicates that 5Cp-C5F4N could also catalyze the conversion of CO2 and H2 to methanol but has a much lower efficiency than our newly designed iron complexes.

HDAC inhibitors TSA and sodium butyrate enhanced the human IL-5 expression by altering histone acetylation status at its promoter region.

PubMed

Han, Songyan; Lu, Jun; Zhang, Yu; Cheng, Cao; Li, Lin; Han, Liping; Huang, Baiqu

2007-02-15

The expression of IL-5 correlated tightly with the maturation and differentiation of eosinophils, and is considered as a cytokine responsible for allergic inflammation. We report here that inhibition of HDAC activity by Trichostatin A (TSA) and sodium butyrate (NaBu), the two specific HDAC inhibitors, resulted in the elevation of both endogenous and exogenous activity of IL-5 promoter. We demonstrated that both the mRNA expression and protein production of IL-5 were stimulated by TSA and NaBu treatments. ChIP assays showed that treatments of TSA and NaBu caused hyperacetylation of histones H3 and H4 on IL-5 promoter in Jurkat cells, which consequently promoted the exogenous luciferase activity driven by this promoter. Moreover, site-directed mutagenesis studies showed that the binding sites for transcription factors NFAT, GATA3 and YY1 on IL-5 promoter were critical for the effects of TSA and NaBu, suggesting that the transcriptional activation of IL-5 gene by these inhibitors was achieved by affecting HDAC function on IL-5 promoter via transcription factors. These data will contribute to elucidating the unique mechanism of IL-5 transcriptional control and to the therapy of allergic disorders related to IL-5.

Synthesis of 2-Butanol by Selective Hydrogenolysis of 1,4-Anhydroerythritol over Molybdenum Oxide-Modified Rhodium-Supported Silica.

PubMed

Arai, Takahiro; Tamura, Masazumi; Nakagawa, Yoshinao; Tomishige, Keiichi

2016-07-07

Rh-MoOx /SiO2 (Mo/Rh=0.13) is an effective catalyst for the hydrogenolysis of 1,4-anhydroerythritol (1,4-AHERY) and provides 2-BuOH in high yield of 51 %. This is the first report of the production of 2-BuOH from 1,4-AHERY by hydrogenolysis. 1,4-AHERY was more suitable as a starting material than erythritol because the 2-BuOH yield from erythritol was low (34 %). Based on the kinetics and comparison of reactivities of the related compounds using Rh-MoOx /SiO2 and Rh/SiO2 catalysts, the modification of Rh/SiO2 with MoOx leads to the high activity and high selectivity to 2-BuOH because of the generation of reactive hydride species and the strong adsorption of 1,4-AHERY on MoOx species. The reaction proceeds by main two routes, (I) the combination of single C-O hydrogenolysis with the desorption of intermediates, a usual route in hydrogenolysis, and (II) multiple C-O hydrogenolysis without the desorption of intermediates from the active site, and the reaction mechanism for Route (II) is proposed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Optimal Hydrophobicity in Ring-Opening Metathesis Polymerization-Based Protein Mimics Required for siRNA Internalization.

PubMed

deRonde, Brittany M; Posey, Nicholas D; Otter, Ronja; Caffrey, Leah M; Minter, Lisa M; Tew, Gregory N

2016-06-13

Exploring the role of polymer structure for the internalization of biologically relevant cargo, specifically siRNA, is of critical importance to the development of improved delivery reagents. Herein, we report guanidinium-rich protein transduction domain mimics (PTDMs) based on a ring-opening metathesis polymerization scaffold containing tunable hydrophobic moieties that promote siRNA internalization. Structure-activity relationships using Jurkat T cells and HeLa cells were explored to determine how the length of the hydrophobic block and the hydrophobic side chain compositions of these PTDMs impacted siRNA internalization. To explore the hydrophobic block length, two different series of diblock copolymers were synthesized: one series with symmetric block lengths and one with asymmetric block lengths. At similar cationic block lengths, asymmetric and symmetric PTDMs promoted siRNA internalization in the same percentages of the cell population regardless of the hydrophobic block length; however, with 20 repeat units of cationic charge, the asymmetric block length had greater siRNA internalization, highlighting the nontrivial relationships between hydrophobicity and overall cationic charge. To further probe how the hydrophobic side chains impacted siRNA internalization, an additional series of asymmetric PTDMs was synthesized that featured a fixed hydrophobic block length of five repeat units that contained either dimethyl (dMe), methyl phenyl (MePh), or diphenyl (dPh) side chains and varied cationic block lengths. This series was further expanded to incorporate hydrophobic blocks consisting of diethyl (dEt), diisobutyl (diBu), and dicyclohexyl (dCy) based repeat units to better define the hydrophobic window for which our PTDMs had optimal activity. High-performance liquid chromatography retention times quantified the relative hydrophobicities of the noncationic building blocks. PTDMs containing the MePh, diBu, and dPh hydrophobic blocks were shown to have superior siRNA internalization capabilities compared to their more and less hydrophobic counterparts, demonstrating a critical window of relative hydrophobicity for optimal internalization. This better understanding of how hydrophobicity impacts PTDM-induced internalization efficiencies will help guide the development of future delivery reagents.

Basal thumb arthritis

PubMed Central

Dias, Richard; Chandrasenan, Jeevan; Rajaratnam, Vaikunthan; Burke, Frank D

2007-01-01

Basal thumb arthritis is a common condition seen in hand clinics across the United Kingdom and is often associated with other pathological conditions such as carpal tunnel syndrome and scaphotrapezial arthritis. Typically, patients complain of pain localised to the base of the thumb. This pain is often activity related, particularly after excessive use involving forceful pinch. A detailed history and examination is normally all that is needed to make the diagnosis. Provocative manoeuvres may be helpful in localising symptoms to the basal joint with degenerative changes or synovitis. Radiographs are useful for confirming the diagnosis and staging the disease in order to plan for surgery. The mainstay of initial treatment of basal thumb arthritis of any stage is activity modifications, rest, nonsteroidal anti‐inflammatory drugs, exercises and splinting. A variety of surgical procedures are available to treat the condition when conservative measures have failed, in order to control symptoms and improve function. We review the current literature and discuss the clinical aspects of this condition, staging, and treatment options available, and the difficulties treating this group of patients. PMID:17267677

New insulin glargine 300 units/mL versus glargine 100 units/mL in people with type 2 diabetes using oral agents and basal insulin: glucose control and hypoglycemia in a 6-month randomized controlled trial (EDITION 2).

PubMed

Yki-Järvinen, Hannele; Bergenstal, Richard; Ziemen, Monika; Wardecki, Marek; Muehlen-Bartmer, Isabel; Boelle, Emmanuelle; Riddle, Matthew C

2014-12-01

To compare the efficacy and safety of new insulin glargine 300 units/mL (Gla-300) with glargine 100 units/mL (Gla-100) in people with type 2 diabetes using basal insulin (≥42 units/day) plus oral antihyperglycemic drugs (OADs). EDITION 2 was a multicenter, open-label, two-arm study. Adults receiving basal insulin plus OADs were randomized to Gla-300 or Gla-100 once daily for 6 months. The primary end point was change in HbA1c. The main secondary end point was percentage of participants with one or more nocturnal confirmed (≤3.9 mmol/L [≤70 mg/dL]) or severe hypoglycemic events from week 9 to month 6. Randomized participants (n = 811) had a mean (SD) HbA₁c of 8.24% (0.82) and BMI of 34.8 kg/m(2) (6.4). Glycemic control improved similarly with both basal insulins; least squares mean (SD) reduction from baseline was -0.57% (0.09) for Gla-300 and -0.56% (0.09) for Gla-100 (mean difference -0.01% [95% CI -0.14 to 0.12]), with 10% higher dose of Gla-300. Less nocturnal confirmed (≤3.9 mmol/L [≤70 mg/dL]) or severe hypoglycemia was observed with Gla-300 from week 9 to month 6 (relative risk 0.77 [95% CI 0.61-0.99]; P = 0.038) and during the first 8 weeks. Fewer nocturnal and any time (24 h) hypoglycemic events were reported during the entire 6-month period. Weight gain was lower with Gla-300 than with Gla-100 (P = 0.015). No between-treatment differences in safety parameters were identified. Gla-300 was as effective as Gla-100 and associated with a lower risk of hypoglycemia during the night and at any time of the day. © 2014 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

High-velocity basal sediment package atop oceanic crust, offshore Cascadia: Impacts on plate boundary processes and fluid migration

NASA Astrophysics Data System (ADS)

Peterson, D. E.; Keranen, K. M.

2017-12-01

Differences in fluid pressure and mechanical properties at megathrust boundaries in subduction zones have been proposed to create varying seismogenic behavior. In Cascadia, where large ruptures are possible but little seismicity occurs presently, new seismic transects across the deformation front (COAST cruise; Holbrook et al., 2012) image an unusually high-wavespeed sedimentary unit directly overlying oceanic crust. Wavespeed increases before sediments reach the deformation front, and the well-laminated unit, consistently of 1 km thickness, can be traced for 50 km beneath the accretionary prism before imaging quality declines. Wavespeed is modeled via iterative prestack time migration (PSTM) imaging and increases from 3.5 km/sec on the seaward end of the profile to >5.0 km/s near the deformation front. Landward of the deformation front, wavespeed is low along seaward-dipping thrust faults in the Quaternary accretionary prism, indicative of rapid dewatering along faults. The observed wavespeed of 5.5 km/sec just above subducting crust is consistent with porosity <5% (Erickson and Jarrard, 1998), possibly reflecting enhanced consolidation, cementation, and diagenesis as the sediments encounter the deformation front. Beneath the sediment, the compressional wavespeed of uppermost oceanic crust is 3-4 km/sec, likely reduced by alteration and/or fluids, lowest within a propagator wake. The propagator wake intersects the plate boundary at an oblique angle and changes the degree of hydration of the oceanic plate as it subducts within our area. Fluid flow out of oceanic crust is likely impeded by the low-porosity basal sediment package except along the focused thrust faults. Decollements are present at the top of oceanic basement, at the top of the high-wavespeed basal unit, and within sedimentary strata at higher levels; the decollement at the top of oceanic crust is active at the toe of the deformation front. The basal sedimentary unit appears to be mechanically strong, similar to observations from offshore Sumatra, where strongly consolidated sediments at the deformation front are interpreted to facilitate megathrust rupture to the trench (Hupers et al., 2017). A uniformly strong plate interface at Cascadia may inhibit microseismicity while building stress that is released in great earthquakes.

A Thematic Literary Unit: Using Literature across the Curriculum in an Elementary Classroom.

ERIC Educational Resources Information Center

Vivian, Diane M.

1990-01-01

"Think Big" is a thematic literary unit, using literature about elephants in a holistic way and attempting to cross the curriculum into the content areas of science and math. It is a way of expanding the basal reading series and providing appropriate and supportive instruction in a cooperative, more interactive learning environment. To…

Five Years of the RoBOT "Rocks Beneath Our Toes" High School Outreach Program

NASA Astrophysics Data System (ADS)

Baxter, E. F.

2011-12-01

The "Rocks Beneath Our Toes" or RoBOT Program began in 2006 as part of an NSF CAREER award through the Geochemistry and Petrology Program. The educational outreach program engages Boston area high school students in a hands on study of rocks and minerals collected in their communities. The goal is to provide high school students a unique window into modern scientific methods of geochemistry and mineralogy and create a higher level of interest and awareness of geoscience amongst Massachusetts secondary school students who are less often exposed to earth science coursework. Beginning with a joint field trip to sampling sites identified by participants, high school students work with Boston University undergraduates enrolled in Mineralogy to analyze their samples in thin section. During the field trip, each BU undergraduate is paired with a high school student. The assignment of student pairings (started in year 2) dramatically increased student interactions and enjoyment. The program culminates with a visit by the high school group to tour BU's lab facilities and work with the undergraduates using the petrographic microscopes to explore their rock. At this visit, BU undergraduates present their semester's work in one-on-one powerpoint presentations from which discussion and microscope work follow. Thus far, >50 high school students, >40 undergraduates, and 7 high school educators were involved in the program. This included participants from three different suburban Boston area high schools and with students enrolled in the BU "Upward Bound" program: an existing program designed to enhance educational opportunities for Boston inner city high school students. Participant reviews indicate great success in achieving the program's goals. Notably, both BU undergraduates and high school students rated the opportunities for interaction with eachother among the best aspects of RoBOT. On a scale of 1 to 10, BU undergraduates rated the following four categories highest: powerpoint presentations to students (8.5); field trip (8.4); working together with microscopes (8.3); would you recommend RoBOT to others (8.2). The high school students rated the following four categories highest: RoBOT provided new geosciences experiences (9.3); working together with microscopes (9.0); tour of BU labs (8.7); powerpoint presentations by students (8.4). In addition, the PI was able to recruit top undergraduate students from Mineralogy and the RoBOT experience to join his research group where they could contribute to broader CAREER award research aims. Challenges and areas for improvement remain for the future of RoBOT. These include keeping participants engaged between the field trip and the BU visit, logistics of field trip scheduling especially with larger groups requiring more field sites and samples, and the ability to gain the interest and collaboration of secondary school educators to initiate the program in the first place. This has proven especially difficult for high schools that do not offer any earth science curriculum, indicating once again the uphill battle in perception that the geosciences face at the secondary school level.

Stoichiometric and catalytic scavengers as protection against nerve agent toxicity: a mini review.

PubMed

Lenz, David E; Yeung, David; Smith, J Richard; Sweeney, Richard E; Lumley, Lucille A; Cerasoli, Douglas M

2007-04-20

Currently fielded treatments for nerve agent intoxication promote survival, but do not afford complete protection against either nerve agent-induced motor and cognitive deficits or neuronal pathology. The use of human plasma-derived butyrylcholinesterase (HuBuChE) to neutralize the toxic effects of nerve agents in vivo has been shown to both aid survival and protect against decreased cognitive function after nerve agent exposure. Recently, a commercially produced recombinant form of human butyrylcholinesterase (r-HuBuChE; PharmAthene Inc.) expressed in the milk of transgenic goats has become available. This material is biochemically similar to plasma-derived HuBuChE in in vitro assays. The pharmacokinetic characteristics of a polyethylene glycol coated (pegylated) form of r-HuBuChE were determined in guinea pigs; the enzyme was rapidly bioavailable with a half-life (t(1/2)) and pharmacokinetic profile that resembled that of plasma-derived huBuChE. Guinea pigs were injected with 140mg/kg (i.m.) of pegylated r-HuBuChE 18h prior to exposure (sc) to 5.5xLD(50) VX or soman. VX and soman were administered in a series of three injections of 1.5xLD(50), 2.0xLD(50), and 2.0xLD(50), respectively, with injections separated by 2h. Pretreatment with pegylated r-HuBuChE provided 100% survival against multiple lethal doses of VX and soman. Guinea pigs displayed no signs of nerve agent toxicity following exposure. Assessments of motor activity, coordination, and acquisition of spatial memory were performed for 2 weeks following nerve agent exposure. There were no measurable decreases in motor or cognitive function during this period. In contrast, animals receiving 1.5xLD(50) challenges of soman or VX and treated with standard atropine, 2-PAM, and diazepam therapy showed 50 and 100% survival, respectively, but exhibited marked decrements in motor function and, in the case of GD, impaired spatial memory acquisition. The advances in this field have resulted in the decision to select both the plasma-derived and the recombinant form of BuChE for advanced development and transition to clinical trials. Efforts have now been expanded to identify a catalytic protein capable of not only binding, but also rapidly hydrolyzing the standard threat nerve agents. Recent work has focused on paraoxonase-1 (PON1), a naturally occurring human serum enzyme with the capacity to catalyze the hydrolysis of nerve agents, albeit too slowly to afford dramatic protection. Using rational design, several amino acids involved in substrate binding have been identified and site-directed mutations have revealed that residue H115 plays an important role in binding. In addition, the stereospecificity of PON1 for the catalytic hydrolysis of soman has been examined. The enzyme exhibits a slight stereospecificity for the C+P+ isomer of soman, which is due more to preferential binding than to selective hydrolysis of this isomer. The results suggest that it may be possible to engineer a mutant form of PON1 with enhanced activity and stereospecificity for the most toxic nerve agent isoforms.

Geology of proximal, small-volume trachyte-trachyandesite pyroclastic flows and associated surge deposits, Roccamonfina volcano, Italy

NASA Astrophysics Data System (ADS)

Giannetti, Bernardino

1998-01-01

This paper describes the 232 ka B.P. MTTT trachyte-trachyandesite pyroclastic succession of Roccamonfina volcano. This small-volume, proximal sequence crops out along Mulino di Sotto, Paratone, and Pisciariello ravines in the southwest sector of the central caldera, and covers a minimum extent of 3.5 km 2 area. It is made up of seven pyroclastic flows and pyroclastic surge units consisting of trachytic ash matrix containing juvenile trachyandesitic scoria and dense lava fragments, pumice clasts of uncertain trachyandesite, and a foreign trachyandesitic lithic facies. Two stratigraphic markers allow correlation of the units. No paleosoils and Plinian fallout have been observed at the base and within the succession. Some lateral grading of scoria and lithic clasts suggests that MTTT derived from three distinct source vents. The sequence consists of a basal ash flow passing laterally to laminated surge deposits (Unit A). This is overlain by a reversely graded scoria and pumice lapilli flow (Unit B) which is in turn overlain by a thinly cross-stratified scoria lapilli surge (Unit C). Unit C is capped by a prominent ash-and-scoria flow (Unit D). A ground layer (Marker MK1) divides Unit D from a massive ignimbrite which grades upcurrent to sand-wave surge deposits (Unit E). Another ground layer (Marker MK2) separates Unit E from Unit F. This unit consists of a basal ignimbrite passing laterally to bedded surge deposits with convolute structures (subunit Fl), and grading upcurrent to a subhorizontally plane-laminated ash cloud (subunit F2) containing near the top a layer of millimetric lithic clasts embedded in fine ash. The succession is closed by the pyroclastic flow Unit G. Surge Unit C can be interpreted in terms of vertical gradients in turbulence, particle concentration, and velocity during flowage, whereas the bedded surge parts present in the massive deposits of Units A and E-F1 can be related to abrupt changes of velocity down the steep slopes of ravines. Reverse grading in Unit B is probably due to grain dispersive pressures. The convolute structures within Fl are related to zones of diagenetic cementation associated with groundwater. Finally, the laminated, fine-grained nature of subunit F2 is interpreted as due to ash clouds elutriated from the basal part of Unit F. Stratigraphic markers MK1-MK2 are ground layer breccias formed by settling of lithic and scoria clasts from overlying units E and F, respectively. Vesiculation and morphologies of glass shards of the MTTT succession suggest that eruptions were essentially driven by magmatic explosions which had an appreciable hydromagmatic component.

Geochemistry and shock petrography of the Crow Creek Member, South Dakota, USA: Ejecta from the 74-Ma Manson impact structure

USGS Publications Warehouse

Katongo, C.; Koeberl, C.; Witzke, B.J.; Hammond, R.H.; Anderson, R.R.

2004-01-01

The Crow Creek Member is one of several marl units recognized within the Upper Cretaceous Pierre Shale Formation of eastern South Dakota and northeastern Nebraska, but it is the only unit that contains shock-metamorphosed minerals. The shocked minerals represent impact ejecta from the 74-Ma Manson impact structure (MIS). This study was aimed at determining the bulk chemical compositions and analysis of planar deformation features (PDFs) of shocked quartz; for the basal and marly units of the Crow Creek Member. We studied samples from the Gregory 84-21 core, Iroquois core and Wakonda lime quarry. Contents of siderophile elements are generally high, but due to uncertainties in the determination of Ir and uncertainties in compositional sources for Cr, Co, and Ni, we could not confirm an extraterrestrial component in the Crow Creek Member. We recovered several shocked quartz grains from basal-unit samples, mainly from the Gregory 84-21 core, and results of PDF measurements indicate shock pressures of at least 15 GPa. All the samples are composed chiefly of SiO2, (29-58 wt%), Al2O3 (6-14 wt%), and CaO (7-30 wt%). When compared to the composition of North American Shale Composite, the samples are significantly enriched in CaO, P2O5, Mn, Sr, Y, U, Cr, and Ni. The contents of rare earth elements (REE), high field strength elements (HFSE), Cr, Co, Sc, and their ratios and chemical weathering trends, reflect both felsic and basic sources for the Crow Creek Member, an inference, which is consistent with the lithological compositions in the environs of the MIS. The high chemical indices of alteration and weathering (CIA' and CIW': 75-99), coupled with the Al2O3-(CaO*,+Na2O -K2O (A-CN'-K) ratios, indicate that the Crow Creek Member and source rocks had undergone high degrees of chemical weathering. The expected ejecta thicknesses at the sampled locations (409 to 219 km from Manson) were calculated to range from about 1.9 to 12.2 cm (for the present-day crater radius of Manson), or 0.4 to 2.4 cm (for the estimated transient cavity radius). The trend agrees with the observed thicknesses of the basal unit of the Crow Creek Member, but the actually observed thicknesses are larger than the calculated ones, indicating that not all of the basal unit comprises impact ejecta. ?? Meteoritical Society, 2004.

Structure-activity relationship of linear peptide Bu-His-DPhe-Arg-Trp-Gly-NH(2) at the human melanocortin-1 and -4 receptors: histidine substitution.

PubMed

Cheung, Adrian Wai-Hing; Danho, Waleed; Swistok, Joseph; Qi, Lida; Kurylko, Grazyna; Rowan, Karen; Yeon, Mitch; Franco, Lucia; Chu, Xin-Jie; Chen, Li; Yagaloff, Keith

2003-01-06

Systematic substitution of His(6) residue using non-selective hMC4R pentapeptide agonist (Bu-His(6)-DPhe(7)-Arg(8)-Trp(9)-Gly(10)-NH(2)) as the template led to the identification of Bu-Atc(6)(2-aminotetraline-2-carboxylic acid)-DPhe(7)-Arg(8)-Trp(9)-Gly(10)-NH(2) which showed moderate selectivity towards hMC4R over hMC1R. Further SAR studies resulted in the discovery of Penta-5-BrAtc(6)-DPhe(7)-Arg(8)-Trp(9)-Gly(10)-NH(2) and Penta-5-Me(2)NAtc(6)-DPhe(7)-Arg(8)-Trp(9)-Gly(10)-NH(2) which are potent hMC4R agonists and are inactive in hMC1R, hMC3R and hMC5R agonist assays.

Stereochemical Alignment in Triphospha[3]ferrocenophanes

PubMed Central

Borucki, Stefan; Kelemen, Zsolt; Maurer, Martin; Bruhn, Clemens

2017-01-01

Abstract A series of triphospha[3]ferrocenophanes of the type Fe(C5H4‐PtBu)2PX with X=H, F, Cl, Br, I, NEt2, tBu has been prepared and characterized by heteronuclear NMR spectroscopy and X‐ray crystallography. Despite having three stereogenic centers, the selective formation of a reduced number of diastereomers (either one or two) has been observed for these ferrocenophanes. Theoretical calculations revealed that the inversion of the central stereogenic center inverts the frontier orbital sequence leading to either an iron or a phosphorus centered HOMO depending on the respective diastereomer. CV measurements supported these results. For the all‐tert‐butyl substituted [3]ferrocenophane Fe(C5H4)2(PtBu)3 a chiral staggered conformation has been found in the solid state which differs substantially from the only other all‐organo substituted [3]ferrocenophane, Fe(C5H4)2(PPh)3. PMID:28557205

Theoretical study of the initial non-radiative 1 Bu → 2 Ag transition in the fluorescence quenching of s-trans-butadiene: Electronic structure methods and quantum dynamics

NASA Astrophysics Data System (ADS)

Komainda, A.; Lefrancois, D.; Dreuw, A.; Köppel, H.

2017-01-01

The photodynamics of s-trans-butadiene in the 6 eV excitation energy range is investigated by ab initio quantum dynamical methods, paying particular attention to the nonadiabatic coupling between the 1Bu and 2Ag singlet excited states. The existence of a conical intersection between their potential energy surfaces is confirmed. Key parameters of the system, like the energy gap between the interacting states and their coupling strength, are critically assessed. Up to eight nuclear degrees of freedom are considered in the dynamical treatment and are shown to lead to a more realistic description of the interactions. The gas phase (jet) UV absorption spectrum is well reproduced. The related ultrafast nonradiative population transfer from 1Bu to 2Ag is the initial processes leading to fluorescence quenching of trans-butadiene.

Molecular Characterization of Staphylococcus aureus Isolates Transmitted between Patients with Buruli Ulcer.

PubMed

Amissah, Nana Ama; Chlebowicz, Monika A; Ablordey, Anthony; Sabat, Artur J; Tetteh, Caitlin S; Prah, Isaac; van der Werf, Tjip S; Friedrich, Alex W; van Dijl, Jan Maarten; Rossen, John W; Stienstra, Ymkje

2015-01-01

Buruli ulcer (BU) is a skin infection caused by Mycobacterium ulcerans. The wounds of most BU patients are colonized with different microorganisms, including Staphylococcus aureus. This study investigated possible patient-to-patient transmission events of S. aureus during wound care in a health care center. S. aureus isolates from different BU patients with overlapping visits to the clinic were whole-genome sequenced and analyzed by a gene-by-gene approach using SeqSphere(+) software. In addition, sequence data were screened for the presence of genes that conferred antibiotic resistance. SeqSphere(+) analysis of whole-genome sequence data confirmed transmission of methicillin resistant S. aureus (MRSA) and methicillin susceptible S. aureus among patients that took place during wound care. Interestingly, our sequence data show that the investigated MRSA isolates carry a novel allele of the fexB gene conferring chloramphenicol resistance, which had thus far not been observed in S. aureus.

Ultrasound-Induced Organogel Formation Followed by Thin Film Fabrication via Simple Doctor Blading Technique for Field-Effect Transistor Applications.

PubMed

Xu, Jiaju; Wang, Yulong; Shan, Haiquan; Lin, Yiwei; Chen, Qian; Roy, V A L; Xu, Zongxiang

2016-07-27

We demonstrate doctor blading technique to fabricate high performance transistors made up of printed small molecular materials. In this regard, we synthesize a new soluble phthalocyanine, tetra-n-butyl peripheral substituted copper(II) phthalocaynine (CuBuPc), that can easily undergo gel formation upon ultrasonic irradiation, leading to the formation of three-dimensional (3D) network composed of one-dimensional (1D) nanofibers structure. Finally, taking the advantage of thixotropic nature of the CuBuPc organogel, we use the doctor blade processing technique that limits the material wastage for the fabrication of transistor devices. Due to the ultrasound induced stronger π-π interaction, the transistor fabricated by doctor blading based on CuBuPc organogel exhibits significant increase in charge carrier mobility in comparison with other solution process techniques, thus paving a way for a simple and economically viable preparation of electronic circuits.

Tapping Water from the Atmosphere: The Bureau of Reclamation's Project Skywater (Invited)

NASA Astrophysics Data System (ADS)

Harper, K.

2010-12-01

Since President Theodore Roosevelt signed the Reclamation Act on 17 June 1902—creating the forerunner of today’s Bureau of Reclamation that was established under Interior in 1907—this agency has been tasked with developing water resources in the US West. These efforts focused on building dams, reservoirs, and irrigation systems. But by the early 1960s, the federal government’s increasing interest in weather control began to attract the attention of BuRec’s leaders. Deciding that it was time to track down solid information on rainmaking techniques, the bureau called upon weather control pioneer Vincent Schaefer for assistance with its plan use weather modification as an adjunct to its water resources development portfolio. In response, Schaefer—writing to the National Science Foundation’s Earl Droessler in late 1961—declared that the Bureau’s proposed project would bring a “responsible, capable, and enthusiastic” group to represent the government and take over the engineering parts of weather modification. Enthusiastic was a bit of an understatement. BuRec was eager to use the atmosphere as a water reservoir, which could dispense moisture to watersheds feeding their earth-bound reservoirs. Contracting with universities—and working to get ahead of its nemesis, the skeptical US Weather Bureau—BuRec announced the artificial precipitation successes of its “Laboratory in the Sky” in early 1963. Although this headquarters-announced “success” was disputed by BuRec’s Denver field office, BuRec’s colorful commissioner Floyd Dominy was determined to press forward. Within months, the bureau was publishing reports indicating that the US West was a “potential future food deficit area” due to an increasing population that was outstripping the availability of ground and surface waters for agriculture. New approaches would be necessary to bring water to BuRec reservoirs for further distribution to municipalities, irrigators, and industries. The Atmospheric Water Resources Program could provide the answer by analyzing reclamation projects’ needs for additional water, the availability of related hydrologic and hydrometeorologic data, and the possibility of obtaining reasonably successful results by tapping into the knowledge and skills of its engineers, hydrometeorologists, and hydrologists. But as far as BuRec was concerned, this program—eventually dubbed Project Skywater—would do more than exploit the atmosphere as a water reservoir. It would provide the bureau with a vehicle to expand its portfolio to the entire nation. And as the eastern part of the nation experienced drought conditions in the mid-1960s, the opportunity was ripe for the picking. Therefore, the story of Skywater’s genesis provides an interesting case study in the intersection of water science, technology, and politics at the highest levels of federal government.

Geochemistry and tectonostratigraphy of the basal allochthonous units of SW Iberia (Évora Massif, Portugal): Keys to the reconstruction of pre-Pangean paleogeography in southern Europe

NASA Astrophysics Data System (ADS)

Fernández, Rubén Díez; Fuenlabrada, José Manuel; Chichorro, Martim; Pereira, M. Francisco; Sánchez-Martínez, Sonia; Silva, José B.; Arenas, Ricardo

2017-01-01

The basal allochthonous units of NW and SW Iberia are members of an intra-Gondwana suture zone that spreads across the Iberian Massif and was formed during the collision of Gondwana and Laurussia in the late Paleozoic. This suture zone is made of allochthonous terranes and is currently preserved as a tectonically dismembered ensemble. A multi-proxy analysis is applied to the basal allochthonous units of Iberia to test their affinity and potential usage for tracing a suture zone. A comparison of the lithostratigraphy, tectonometamorphic evolution, geochronology, and geochemical characteristics of the Ediacaran series of these units reveals striking affinities. They derive from rather similar immature sedimentary successions, deposited along the same continental margin, and in relation to a Cadomian magmatic arc. Sm-Nd systematics indicates that the isotopic sources are among the oldest of the Iberian Massif (ca. 2.15-1.5 Ga), suggesting a very strong contribution from the West African Craton. These Ediacaran series were affected by high-P and low- to medium-T metamorphism (blueschist to eclogite facies) during the Late Devonian (ca. 370 Ma). They occur below allochthonous ophiolitic sequences, and on top of autochthonous or parautochthonous domains lacking of high-P and low- to medium-T Devonian metamorphism, i.e., tectonically sandwiched between lithosphere-scale thrusts. The combination of all these characteristics makes these particular Ediacaran series different from the rest of the terranes of the Iberian Massif. Such singularity could be useful for tracing more occurrences of the same suture zone along the Variscan orogen, particularly in cases where its preservation and recognition may be cryptic. It also contributes to improve the paleogeographic reconstruction of the margin of Gondwana during the Ediacaran.

Vanadium(V) Complexes with Substituted 1,5-bis(2-hydroxybenzaldehyde)carbohydrazones and Their Use As Catalyst Precursors in Oxidation of Cyclohexane.

PubMed

Dragancea, Diana; Talmaci, Natalia; Shova, Sergiu; Novitchi, Ghenadie; Darvasiová, Denisa; Rapta, Peter; Breza, Martin; Galanski, Markus; Kožı́šek, Jozef; Martins, Nuno M R; Martins, Luísa M D R S; Pombeiro, Armando J L; Arion, Vladimir B

2016-09-19

Six dinuclear vanadium(V) complexes have been synthesized: NH4[(VO2)2((H)LH)] (NH4[1]), NH4[(VO2)2((t-Bu)LH)] (NH4[2]), NH4[(VO2)2((Cl)LH)] (NH4[3]), [(VO2)(VO)((H)LH)(CH3O)] (4), [(VO2)(VO)((t-Bu)LH)(C2H5O)] (5), and [(VO2)(VO)((Cl)LH)(CH3O)(CH3OH/H2O)] (6) (where (H)LH4 = 1,5-bis(2-hydroxybenzaldehyde)carbohydrazone, (t-Bu)LH4 = 1,5-bis(3,5-di-tert-butyl-2-hydroxybenzaldehyde)carbohydrazone, and (Cl)LH4 = 1,5-bis(3,5-dichloro-2-hydroxybenzaldehyde)carbohydrazone). The structures of NH4[1] and 4-6 have been determined by X-ray diffraction (XRD) analysis. In all complexes, the triply deprotonated ligand accommodates two V ions, using two different binding sites ONN and ONO separated by a diazine unit -N-N-. In two pockets of NH4[1], two identical VO2(+) entities are present, whereas, in those of 4-6, two different VO2(+) and VO(3+) are bound. The highest oxidation state of V ions was corroborated by X-ray data, indicating the presence of alkoxido ligand bound to VO(3+) in 4-6, charge density measurements on 4, magnetic susceptibility, NMR spectroscopy, spectroelectrochemistry, and density functional theory (DFT) calculations. All four complexes characterized by XRD form dimeric associates in the solid state, which, however, do not remain intact in solution. Compounds NH4[1], NH4[2], and 4-6 were applied as alternative selective homogeneous catalysts for the industrially significant oxidation of cyclohexane to cyclohexanol and cyclohexanone. The peroxidative (with tert-butyl hydroperoxide, TBHP) oxidation of cyclohexane was performed under solvent-free and additive-free conditions and under low-power microwave (MW) irradiation. Cyclohexanol and cyclohexanone were the only products obtained (high selectivity), after 1.5 h of MW irradiation. Theoretical calculations suggest a key mechanistic role played by the carbohydrazone ligand, which can undergo reduction, instead of the metal itself, to form an active reduced form of the catalyst.

Experimental demonstration of the possible role of Acanthamoeba polyphaga in the infection and disease progression in Buruli Ulcer (BU) using ICR mice

PubMed Central

Azumah, Bright K.; Addo, Phyllis G.; Dodoo, Alfred; Awandare, Gordon; Mosi, Lydia; Boakye, Daniel A.

2017-01-01

The transmission of Buruli ulcer (BU), caused by Mycobacterium ulcerans (MU), remains puzzling although a number of hypothesis including through bites of infected aquatic insects have been proposed. We report the results of experiments using ICR mice that give credence to our hypothesis that Acanthamoeba species may play a role in BU transmission. We cocultured MU N2 and MU 1615 which expresses red fluorescent protein (RFP) and Acanthamoeba polyphaga (AP), and confirmed infected AP by Ziehl-Neelsen (ZN) staining. We tested for viability of MU inside AP and observed strong RFP signals inside both trophozoites and cysts after 3 and 42 days of coculturing respectively. ICR mice were topically treated, either on shaved intact or shaved pinpricked rumps, with one of the following; MU N2 only (2.25 x 106 colony forming units [CFU] / ml), MU N2:AP coculture (2.96 x 104 CFU: 1.6 x 106 cells/ml), AP only (1.6 x 106 cells/ml), PYG medium and sterile distilled water. Both MU N2 only and MU N2:AP elicited reddening on day (D) 31; edema on D 45 and D 44 respectively, and ulcers on D 49 at pinpricked sites only. To ascertain infectivity and pathogenicity of MU N2 only and MU N2:AP, and compare their virulence, the standard mouse footpad inoculation method was used. MU N2:AP elicited reddening in footpads by D 3 compared to D 14 with MU N2 only of the same dose of MU N2 (2.96 x 104 CFU). ZN-stained MU were observed in both thin sectioned and homogenized lesions, and aspirates from infected sites. Viable MU N2 were recovered from cultures of the homogenates and aspirates. This study demonstrates in ICR mice MU transmission via passive infection, and shows that punctures in the skin are prerequisite for infection, and that coculturing of MU with AP enhances pathogenesis. PMID:28329001

The Study to Improve Tsunami Preparedness Education in Turkey

NASA Astrophysics Data System (ADS)

Sakamoto, Mayumi; Tanırcan, Gülüm; Kaneda, Yoshiyuki; Puskulcu, Seyhun; Kumamoto, Kunihiko

2016-04-01

Compared to its long history on disastrous earthquakes, disaster education history in Turkey is rather short. It has just started with an initiative of Disaster Preparedness Education Unit of Bogazici University (BU/DPEU) after 1999 Kocaeli Earthquake. Training modules and materials on disaster preparedness were prepared both for students, teachers and community. Regarding to the school education, the Ministry of National Education (MoNE) reformed their education plan in 2003, and disaster education became one of eight focused components for primary-middle education. In 2011-2014 MoNE had conducted "School-based Disaster Education Project" in collaboration with Japan International Cooperation Agency (JICA). The majority of the school education materials focus more on earthquake and there are very few education programs on tsunami. Within the MarDiM (Earthquake and Tsunami Disaster Mitigation in the Marmara Region and Disaster Education in Turkey) project between Turkey and Japan a multidisciplinary engineering research as well as development of disaster education, tsunami education booklet and video were newly developed in 2015. In order to investigate students' knowledge natural disasters and disaster preparedness with focus on tsunami, a questionnaire based survey was conducted. The survey aims to clarify following questions: 1) how students obtain natural disaster information, 2) how students prepare for natural disaster, 3) knowledge on tsunami (hazard mechanism, evacuation behavior, historical disaster). The study was conducted by BU/DPEU in 2015 and 375 students answered the questionnaire. Results showed that students have more interest on earthquake, flood, tsunami and landslide followed it. Most students have heard about tsunami and the school is a key resource of their information. They know relatively well about tsunami mechanism, however, they have less knowledge on tsunami evacuation behavior and tsunami history in Turkey. In order to let students have more knowledge on tsunami, tsunami class was provided by BU/DPEU using tsunami booklet and videos. The class was evaluated by before/after class tests and the result showed improvement on students' knowledge. The result showed the necessity to integrate tsunami education materials in school disaster education curriculum.

Resistance surveillance program report for selected European nations (2011).

PubMed

Jones, Ronald N; Flonta, Mirela; Gurler, Nazahat; Cepparulo, Mario; Mendes, Rodrigo E; Castanheira, Mariana

2014-04-01

In the European component of the Regional Resistance Surveillance study for 2011, a total of 21 countries were monitored for antimicrobial resistance patterns including Belgium, Bulgaria (BU), Croatia, Czech Republic, France (F), Germany (GE), Greece (GR), Ireland (IR), Israel (IS), Italy (IT), Poland (PO), Portugal (PT), Romania (RO), Russia (RU), Slovakia (SK), Slovenia, Spain, Sweden (SW), Turkey (T), Ukraine, and United Kingdom. Results from testing 12,572 strains (100 [BU] to 1535 [F] per nation) were interpreted by contemporary published breakpoints. Samples from 47 hospitals were reference tested against agents such as amikacin (AMK), cefoperazone/sulbactam (C/S), colistin (COL), levofloxacin, linezolid (LZD), tigecycline (TIG), vancomycin (VAN), and 21 others. Among Staphylococcus aureus, LZD (MIC90, 2 μg/mL), TIG (MIC90, 0.12 μg/mL), and VAN (MIC90, 1 μg/mL) exhibited complete coverage and methicillin resistance rates among nations (average, 31%) ranged from 0.9% (SW) to 60.0-60.2% (PT, SK). Seven LZD-resistant coagulase-negative staphylococci (only 1.1% resistance overall) were noted in 5 nations, and a Staphylococcus simulans strain (MIC, 8 μg/mL from RO) had L3 mutations (N130D, G152A, F147S, A157R); also 6 LZD-resistant enterococci were detected in 3 countries (GE, IR, T). VAN-resistant enterococci (10% overall; 84% VanA) were found in 14 countries, highest in GE and IR (23.0%). The ESBL phenotype rate for Escherichia coli was 20.1% (range, 0.9% [SW] to 70.0-89.7% [BU, RU]), best inhibited by COL (100.0% S), TIG (100.0%), AMK (83.3-94.1%), C/S (81.0%), and carbapenems (>99.0%; resistant strains in IS and T). Klebsiella spp. had greater ESBL rates (45.7% overall, range 2.5-100.0%), as well as carbapenem resistance (8.3% overall, greatest in BU, GR, IS, IT, PO, RO, RU, T). Non-fermentative Gram-negative bacilli (Pseudomonas aeruginosa, Acinetobacter [ACB]) were generally less susceptible, except against COL (99.2-99.6% S) and TIG (95.0% inhibited at ≤2 μg/mL; ACB only). The following carbapenemases were detected: VIM-1 (2 countries); IMP-1 (1 from T); KPC-2 or -3 (2 countries); VIM-4 (1 from PO), NDM-1 (2 in RO; 2 centers); and OXA-48 or -162 (5 from T; 2 centers). European surveillance sampling demonstrates a wide array of resistant isolates, less prevalent among Gram-positive cocci that remain inhibited by several available agents. However, beta-lactamase-mediated mechanisms have spread widely among Gram-negative bacilli, especially across the Eastern and Southern European nations, severely limiting infection chemotherapy and necessitating escalated antimicrobial stewardship. © 2014.

Eruptive history, petrology, and petrogenesis of the Joe Lott Tuff Member of the Mount Belknap Volcanics, Marysvale volcanic field, west-central Utah

USGS Publications Warehouse

Budding, Karin E.

1982-01-01

The Joe Lott Tuff Member of the Mount Belknap Volcanics is the largest rhyolitic ash-flow tuff sheet in the Marysvale volcanic field. It was erupted 19 m.y. ago, shortly after the changeover from intermediate-composition calc-alkalic volcanism to bimodal basalt-rhyolite volcanism. Eruption of the tuff resulted in the formation of the Mount Belknap Caldera whose pyroclastic intracaldera stratigraphy parallels that in the outflow facies. The Joe Loft Tuff Member is a composite ash-flow sheet that changes laterally from a simple cooling unit near the source to four distinct cooling units toward the distal end. The lowest of these units is the largest and most widespread; it is 64 m thick and contains a basal vitrophyre. Eruption of the lower unit led to the initial collapse of the caldera. The lower unit is followed upward by a 43 m middle unit, a 26 m pink-colored unit which is separated by a prominent air- fall layer, and a 31 m upper unit. The Joe Loft Tuff Member is an alkali rhyolite with 75.85-77.31 wt. % silica and 8.06-9.32 wt. % K2O+Na2O; the agpaitic index (Na2O+ K2O/Al2O3) is .77-.98. The tuff contains about I% phenocrysts of quartz, sanidine, oligoclase, augite, apatite, zircon, sphene, biotite, and oxidized Fe-Ti oxides. The basal vitrophyre contains accessory allanite, chevkinite, and magnesiohastingsite. The main cooling units are chemically and mineralogically zoned indicating that the magma chamber restratified prior to each major eruption. Within each of the two thickest cooling units, the mineralogy changes systematically upwards; the Or content and relative volume of sanidine decreases and An content of plagioclase increases. The basal vitrophyre of the lower unit has a bulk composition that lies in the thermal trough near the minima of Or-Ab-Q at 1 kb PH2O. Microprobe analyses of feldspar and chemical modeling on experimental systems indicate that pre-eruption temperatures were near 750?C and that the temperature increased during the eruption of the cooling units. The chemical gradients in the apatite and whole-rock data in the Joe Loft Tuff Member and the consistent mineral assemblages throughout the ash-flow cannot be explained by crystal settling. The fractionation of the Joe Lott Tuff Member appears to closer fit the model of convection-driven thermogravitational diffusion.

Stratigraphy of Zambian copperbelt orebodies

NASA Astrophysics Data System (ADS)

Binda, Pier L.

1994-11-01

The subdivision of the Roan Supergroup in three informal units instead of the traditional Lower Roan/Upper Roan allows a better understanding of facies relationships. The lower division (Siliciclastic Unit) consists of a variable thickness of continental conglomerates and erenites. The middle division (Mixed Unit) consists of a wedge of carbonate and siliciclastic lithologies tapering to the south-west and deposited in a shallow sea. The upper division (Carbonate Unit or Upper Roan s.s.) is a thick succession of dolostones, subordinate argillites and breccias that directly overlies, but is probably in tectonic contact with, the Siliciclastic Unit in the south-western part of the Copperbelt. Reference boundaries for the Mixed and Siliciclastic Units are given for all mining localities of the Zambian Copperbelt. The basal part of the Mixed Unit, host to the most important CuCo orebodies, was deposited during a major marine transgression which, proceeding from SW-NE, swiftly inundated the whole Copperbelt basin. Thus, the Mufulira Ore Formation can be considered as the near-shore facies of the basinal ore shale. The transition from the Mufulira arenites to the Chambishi silty, ore shale has been effaced by erosional or tectonic stripping of the Roan sediments on the Kafue anticline, whereas the transition from silty to carbonaceous ore shale is well documented in the southern part of the Chambishi-Nkana basin. Concomitant with the NE-SW lithofacies changes within the basal Mixed Unit, there is marked decrease in Cu grade and content from the Mufulira wacke and arenite to the silty ore shale of the northern Chambishi basin and the carbonaceous and pyritic ore shale of the southern Chambishi basin. Cobalt is virtually absent in the Mufulira Ore Formation, reaches ore grade in the silty ore shale and occurs in trace amounts in the carbonaceous ore shale. Thus, the correlation of the basal Mixed Unit reveals a hitherto undetected regional metal zoning akin to that noted in parts of individual Copperbelt basin. The middle portion of the Mixed Unit contains at least one laterally continuous Cu mineralization in the arkosic arenite with minor occurrences of local significance. The Siliciclastic Unit contains Cu concentrations at several stratigraphical levels, but precise correlation of footwall orebodies is precluded by the heterogeneity of the clastic wedges of local provenance. The Mixed Unit of the Zambian Copperbelt can be correlated lithostratigraphically with the Serie des Mines of Shaba. A bed-by-bed correlation of the Kamoto (Zaire) and Mindola (Zambia) Ore Formations is proposed. The southern provenance of the Shaba nappes is supported.

Hyperoxia, unlike phorbol ester, induces glutathione peroxidase through a protein kinase C-independent mechanism.

PubMed Central

Jornot, L; Junod, A F

1997-01-01

Human selenium-dependent glutathione peroxidase (GP) is implicated as a mechanism of resistance against oxygen free radicals. The 5' flanking sequence upstream from the coding region of GP contained an oxygen-responsive element termed ORE1 that is responsive to hypoxia, as well as several copies of the activator protein-1 (AP-1)- and AP-1-like-binding sites. In this study, we sought to define the molecular events that lead to GP gene transcription in response to hyperoxia in human umbilical-vein endothelial cells, and asked whether such induction is mimicked and sustained by activation of protein kinase C (PKC) by phorbol esters. Treatment of cells with 100 nM phorbol 12,13-dibutyrate (PdBu) induced a delayed (24-48 h) but significant (2-fold) increase in steady-state GP mRNA levels. Steady-state GP mRNA levels also rose after exposure to 95% O2, again after considerable delay (48-72 h). For both PdBu and oxygen, induction was transcriptionally regulated, as demonstrated by nuclear run-on experiments. The simulations by PdBu and oxygen were additive. In contrast with PdBu, hyperoxia did not stimulate translocation of PKC from the cytosol to the particulate fraction, although the specific activity of both cytosolic and particulate-associated PKC was increased 2-fold in cells exposed to 95% O2 for 5 days. In addition, gel mobility-shift assays using double-stranded tumour-promoting-agent-responsive element (TRE) and nuclear extracts derived from phorbol- and oxygen-treated cells revealed that PdBu, but not hyperoxia, increased AP-1 DNA-binding activity. On the other hand, the up-regulation of GP expression by oxygen could not be accounted for by the ORE1 core sequence, since no specific protein-DNA binding activity could be detected using nuclear extracts from hyperoxic cells and ORE1. Taken together, these results suggest that there may be different molecular mechanisms controlling GP expression. After exposure to PdBu, GP undergoes transcriptional activation via a process that can be readily explained by a classic AP-1 interaction with the TRE sites in the GP promoter. During hyperoxia, GP also undergoes transcriptional activity, but via a process that appears to involve neither TRE nor ORE1. PMID:9337858

Characterization of human cytochrome P450s involved in the bioactivation of tri-ortho-cresyl phosphate (ToCP).

PubMed

Reinen, Jelle; Nematollahi, Leyla; Fidder, Alex; Vermeulen, Nico P E; Noort, Daan; Commandeur, Jan N M

2015-04-20

Tri-ortho-cresyl phosphate (ToCP) is a multipurpose organophosphorus compound that is neurotoxic and suspected to be involved in aerotoxic syndrome in humans. It has been reported that not ToCP itself but a metabolite of ToCP, namely, 2-(ortho-cresyl)-4H-1,2,3-benzodioxaphosphoran-2-one (CBDP), may be responsible for this effect as it can irreversibly bind to human butyrylcholinesterase (BuChE) and human acetylcholinesterase (AChE). The bioactivation of ToCP into CBDP involves Cytochrome P450s (P450s). However, the individual human P450s responsible for this bioactivation have not been identified yet. In the present study, we aimed to investigate the metabolism of ToCP by different P450s and to determine the inhibitory effect of the in vitro generated ToCP-metabolites on human BuChE and AChE. Human liver microsomes, rat liver microsomes, and recombinant human P450s were used for that purpose. The recombinant P450s 2B6, 2C18, 2D6, 3A4 and 3A5 showed highest activity of ToCP-bioactivation to BuChE-inhibitory metabolites. Inhibition experiments using pooled human liver microsomes indicated that P450 3A4 and 3A5 were mainly involved in human hepatic bioactivation of ToCP. In addition, these experiments indicated a minor role for P450 1A2. Formation of CBDP by in-house expressed recombinant human P450s 1A2 and 3A4 was proven by both LC-MS and GC-MS analysis. When ToCP was incubated with P450 1A2 and 3A4 in the presence of human BuChE, CBDP-BuChE-adducts were detected by LC-MS/MS which were not present in the corresponding control incubations. These results confirmed the role of human P450s 1A2 and 3A4 in ToCP metabolism and demonstrated that CBDP is the metabolite responsible for the BuChE inactivation. Interindividual differences at the level of P450 1A2 and 3A4 might play an important role in the susceptibility of humans in developing neurotoxic effects, such as aerotoxic syndrome, after exposure to ToCP.

Relationship Between Paraoxonase-1 and Butyrylcholinesterase Activities and Nutritional Status in Mexican Children.

PubMed

Ramírez-Jiménez, Rocío; Martínez-Salazar, María Fernanda; Almenares-López, Damianys; Yáñez-Estrada, Leticia; Monroy-Noyola, Antonio

2018-03-01

The enzymes butyrylcholinesterase (BuChE) and paraoxonase-1 (PON1) are the primary bioscavenging enzymes in serum and exhibit antioxidant and anti-inflammatory activities. PON1 has been associated with diseases caused by high oxidative stress, whereas BuChE appears to be involved in the pathophysiology of the metabolic syndrome and related disorders. It has been suggested that children from rural communities in Mexico may have a predisposition to develop obesity or type 2 diabetes during adolescence or adulthood. The objective of this study was to determine whether associations exist between the paraoxonase (PONase)/arylesterase (AREase) activity of PON1, its PON1-Q192R and PON1-L55M polymorphisms, and BuChE activity with the nutritional status and lipid profiles in a group of children from rural communities in Mexico. A group of 97 boys and girls from a rural community in Mexico were assessed for body mass index, the enzymatic activities of BuChE, PONase, and AREase were measured in serum, and their lipid profiles were determined. Genetic polymorphisms of PON1-L55M and PON1-Q192R were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The children were classified into four groups: thinness, normal weight, overweight, and obese. Of the children studied, 34.4% were overweight and obese. The mean age of the participants was 9.5 years (standard deviation = 1.8). The L allele of the PON1-L55M genotype was the most frequent (83.3%), and the R allele of the PON1-Q192R genotype was the most frequent (61.8%). Overweight and obese children had higher values of BuChE, total cholesterol, triglycerides (TG), and lower high-density lipoprotein (HDL-C) values than children with thinness or normal weight (P = 0.028, P = 0.019, P = 0.004, P = 0.069 and P = 0.021, respectively). The levels of AREase and PONase and the prevalence of PON1-L55M and PON1-Q192R genotypes were similar between groups (P = 0.484 and P = 0.380, respectively). This study establishes a positive association of BuChE activity with nutritional status and serum TG.

Iron-mediated and -catalyzed metalative cyclization of electron-withdrawing-group-substituted alkynes and alkenes with Grignard reagents.

PubMed

Hata, Takeshi; Sujaku, Shiro; Hirone, Naoki; Nakano, Kirihiro; Imoto, Junsuke; Imade, Haduki; Urabe, Hirokazu

2011-12-16

Treatment of ethyl (E)-5,5-bis[(benzyloxy)methyl]-8-(N,N-diethylcarbamoyl)-2-octen-7-ynoate with an iron reagent generated from FeCl(2) and tBuMgCl in a ratio of 1:4 (abbreviated as FeCl(2)/4 tBuMgCl) afforded ethyl [4,4-bis[(benzyloxy)methyl]-2-[(E)-(N,N-diethylcarbamoyl)methylene]cyclopent-1-yl]acetate in good yield. Deuteriolysis of an identical reaction mixture afforded the bis-deuterated product ethyl [4,4-bis[(benzyloxy)methyl]-2-[(E)-(N,N-diethylcarbamoyl)deuteriomethylene]cyclopent-1-yl]deuterioacetate, thus confirming the existence of the corresponding dimetalated intermediate. The latter intermediate can react with halogens or aldehydes to facilitate further synthetic transformations. The amount of FeCl(2) was reduced to catalytic levels (10 mol % relative to enyne), and catalytic cyclizations of this sort proceeded with yields comparable to those of the aforementioned stoichiometric reactions. The cyclization of diethyl (E,E)-2,7-nonadienedioate with a stoichiometric amount of FeCl(2)/4 tBuMgCl, followed by the addition of sBuOH as a proton source, afforded a mixture of 2-(ethoxycarbonyl)-3-bicyclo[3.3.0]octanone and its enol form in good yield. The use of aldehyde or ketone in place of sBuOH afforded 2-(ethoxycarbonyl)-3-bicyclo[3.3.0]octanone, which has an additional hydroxyalkyl side chain. Additionally, the metalation of a carbon-carbon unsaturated bond in N,N-diethyl-5,5-bis[(benzyloxy)methyl]-7,8-epoxy-2-octynamide or (E)-3,3-dimethyl-6-(N,N-diethylcarbamoyl)-5-hexenyl p-toluenesulfonate with FeCl(2)/4 tBuMgCl or FeCl(2)/4 PhMgBr was followed by an intramolecular alkylation with an epoxide or alkyl p-toluenesulfonate to afford 5,5-bis[(benzyloxy)methyl]-3-[(E)-(N,N-diethylcarbamoyl)methylene]-1-cyclohexanol or N,N-diethyl(3,3-dimethylcyclopentyl)acetamide after hydrolysis. In both cases, the remaining metalated portion α to the amide group was confirmed by deuteriolysis and could be utilized for an alkylation with methyl iodide. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Helicopter logging productivity on harvesting operations in southeast Alaska, using ecologically based silvicultural prescriptions.

Treesearch

L. Christian; A. Brackley

2007-01-01

This study examines production rates and costs for felling and helicopter yarding on eight units harvested in accordance with ecologically based silvicultural prescriptions. The units represent five levels of basal area retention. The levels of retention had irregular spatial arrangements caused by gaps and clumps that ranged from 0 percent retention (clearcut) to 75...

Study of alcohol fuel of butanol and ethanol effect on the compression ignition (CI) engine performance, combustion and emission characteristic

NASA Astrophysics Data System (ADS)

Aziz, M. A.; Yusop, A. F.; Mat Yasin, M. H.; Hamidi, M. A.; Alias, A.; Hussin, H.; Hamri, S.

2017-10-01

Diesel engine which is one of the larger contributors to total consumption for petroleum is an attractive power unit used widely in many fields. However, diesel engines are among the main contributors to air pollutions for the large amount of emissions, such as CO, CO2 and NOx lead to an adverse effect on human health. Many researches have been done to find alternative fuels that are clean and efficient. Biodiesel is preferred as an alternative source for diesel engine which produces lower emission of pollutants. This study has focused on the evaluation of diesel and alcohol-diesel fuel properties and also the performance, combustion and exhaust emission from diesel engine fuelled with diesel and alcohol. Butanol and ethanol is blend with diesel fuel at 1:9 ratio. There are three test fuel that is tested which Diesel (100% diesel), D90BU10 (10% Butanol and 90% diesel) and D90E10 (10% Ethanol and 90% diesel). The comparison between diesel and alcohol-diesel blend has been made in terms of fuel properties characterization, engine performance such as brake power (BP) and brake specific fuel consumption (BSFC) also the in cylinder maximum pressure characteristic. Thus, exhaust gas emission of CO, CO2, NOx and O2 emission also has been observed at constant load of 50% but in different operating engine speed (1100 rpm, 1400 rpm, 1700 rpm, 2000 rpm and 2300 rpm). The results show the addition of 10% of each butanol and ethanol to diesel fuel had decreased the fuel density about 0.3% to 0.5% compared to mineral diesel. In addition, viscosity and energy content are also decrease. The addition of 10% butanol had improved the fuel cetane number however the ethanol blends react differently. In term of engine performance, as the engine speed increased, BP output also increase respectively. Hence, the alcohol blends fuel generates lower BP compared to diesel, plus BSFC for all test fuel shows decreasing trend at low and medium speed, however increased gradually at higher engine speed. Thus, D90BU10 had higher BSFC compared to mineral diesel and D90E10. In general, the addition of alcohol blend in diesel fuel had increase the BSFC. In term of in cylinder pressure, as the engine speed is increased, the crank angle noted to move away from TDC for all test fuel. The maximum cylinder pressure increased at low and medium speed, but decrease in higher engine speed. The addition of 10% of butanol and ethanol in the mineral diesel decreased the maximum cylinder pressure. Meanwhile, O2 emission of D90E10 is higher compared to D90BU10 due to higher oxygen content found in ethanol. The CO2 emission of D90BU10 recorded higher compared to mineral diesel due to the high oxygen contents in the alcohol. CO emission of alcohol blend on the other hand had lower emission at higher engine speed compared to mineral diesel. As engine speed is increased, NOx emission of mineral diesel and D90E10 had decreased gradually. However, D90BU10 had increased of NOx emission at lower to medium engine speed, than gradually decreased at higher engine speed.

Ligand-to-ligand charge-transfer transitions of platinum(II) complexes with arylacetylide ligands with different chain lengths: spectroscopic characterization, effect of molecular conformations, and density functional theory calculations.

PubMed

Tong, Glenna So Ming; Law, Yuen-Chi; Kui, Steven C F; Zhu, Nianyong; Leung, King Hong; Phillips, David Lee; Che, Chi-Ming

2010-06-11

The complexes [Pt(tBu(3)tpy){C[triple bond]C(C(6)H(4)C[triple bond]C)(n-1)R}](+) (n = 1: R = alkyl and aryl (Ar); n = 1-3: R = phenyl (Ph) or Ph-N(CH(3))(2)-4; n = 1 and 2, R = Ph-NH(2)-4; tBu(3)tpy = 4,4',4''-tri-tert-butyl-2,2':6',2''-terpyridine) and [Pt(Cl(3)tpy)(C[triple bond]CR)](+) (R = tert-butyl (tBu), Ph, 9,9'-dibutylfluorene, 9,9'-dibutyl-7-dimethyl-amine-fluorene; Cl(3)tpy = 4,4',4''-trichloro-2,2':6',2''-terpyridine) were prepared. The effects of substituent(s) on the terpyridine (tpy) and acetylide ligands and chain length of arylacetylide ligands on the absorption and emission spectra were examined. Resonance Raman (RR) spectra of [Pt(tBu(3)tpy)(C[triple bond]CR)](+) (R = n-butyl, Ph, and C(6)H(4)-OCH(3)-4) obtained in acetonitrile at 298 K reveal that the structural distortion of the C[triple bond]C bond in the electronic excited state obtained by 502.9 nm excitation is substantially larger than that obtained by 416 nm excitation. Density functional theory (DFT) and time-dependent DFT (TDDFT) calculations on [Pt(H(3)tpy)(C[triple bond]CR)](+) (R = n-propyl (nPr), 2-pyridyl (Py)), [Pt(H(3)tpy){C[triple bond]C(C(6)H(4)C[triple bond]C)(n-1)Ph}](+) (n = 1-3), and [Pt(H(3)tpy){C[triple bond]C(C(6)H(4)C[triple bond]C)(n-1)C(6)H(4)-N(CH(3))(2)-4}](+)/+H(+) (n = 1-3; H(3)tpy = nonsubstituted terpyridine) at two different conformations were performed, namely, with the phenyl rings of the arylacetylide ligands coplanar ("cop") with and perpendicular ("per") to the H(3)tpy ligand. Combining the experimental data and calculated results, the two lowest energy absorption peak maxima, lambda(1) and lambda(2), of [Pt(Y(3)tpy)(C[triple bond]CR)](+) (Y = tBu or Cl, R = aryl) are attributed to (1)[pi(C[triple bond]CR)-->pi*(Y(3)tpy)] in the "cop" conformation and mixed (1)[d(pi)(Pt)-->pi*(Y(3)tpy)]/(1)[pi(C[triple bond]CR)-->pi*(Y(3)tpy)] transitions in the "per" conformation. The lowest energy absorption peak lambda(1) for [Pt(tBu(3)tpy){C[triple bond]C(C(6)H(4)C[triple bond]C)(n-1)C(6)H(4)-H-4}](+) (n = 1-3) shows a redshift with increasing chain length. However, for [Pt(tBu(3)tpy){C[triple bond]C(C6H4C[triple bond]C)(n-1)C(6)H(4)-N(CH(3))(2)-4}](+) (n = 1-3), lambda(1) shows a blueshift with increasing chain length n, but shows a redshift after the addition of acid. The emissions of [Pt(Y(3)tpy)(C[triple bond]CR)](+) (Y = tBu or Cl) at 524-642 nm measured in dichloromethane at 298 K are assigned to the (3)[pi(C[triple bond]CAr)-->pi*(Y(3)tpy)] excited states and mixed (3)[d(pi)(Pt)-->pi*(Y(3)tpy)]/(3)[pi(C[triple bond]C)-->pi*(Y(3)tpy)] excited states for R = aryl and alkyl groups, respectively. [Pt(tBu(3)tpy){C[triple bond]C(C(6)H(4)C[triple bond]C)(n-1)C(6)H(4)-N(CH(3))(2)-4}](+) (n = 1 and 2) are nonemissive, and this is attributed to the small energy gap between the singlet ground state (S(0)) and the lowest triplet excited state (T(1)).

A New Silicon-Containing Bis(Cyanate) Ester Resin with Improved Thermal Oxidation and Moisture Resistance

DTIC Science & Technology

2006-05-23

making it an ideal comparative material. Scheme 1 BnO Br Si R R OYYO Si R R NCO OCN 1. n- BuLi THF/-78 oC 2. Me2SiCl2 1; R = Me, Y= Bn H2...carbonate in DMF) was treated with n- BuLi (15.2 mL, 38 mmol) and allowed to react with stirring for 30 min. This mixture, now heterogeneous, was

Direct dehydroxytrifluoromethylthiolation of alcohols using silver(I) trifluoromethanethiolate and tetra-n-butylammonium iodide.

PubMed

Liu, Jian-Bo; Xu, Xiu-Hua; Chen, Zeng-Hao; Qing, Feng-Ling

2015-01-12

An unprecedented reaction for the direct trifluoromethylthiolation and fluorination of alkyl alcohols using AgSCF3 and nBu4NI has been developed. The trifluoromethylthiolated compounds and alkyl fluorides were selectively formed by changing the ratio of AgSCF3/nBu4NI. This protocol is tolerant of different functional groups and might be applicable to late-stage trifluoromethylthiolation of alcohols. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Diagnostics for Intelligent Control of MPD Engines

DTIC Science & Technology

1988-11-15

Comparison of finite and infinite dimensional systems. -29- V r eAtvo which satisfies - ( eAtv ,,) =AeAtvo -Av where eAt is the transition matrix defined by, eA...Bu (6-1) and v(o) =v o where vER’, ueRm, Ae2(Rn,R’), and Bei(Rm,Ra). The solution of this equation at time t is t v(t) = eAtv + f eA(t-S)Bu(s) ds (6-2

Some physicochemical and rheological properties of starch isolated from avocado seeds.

PubMed

Chel-Guerrero, Luis; Barbosa-Martín, Enrique; Martínez-Antonio, Agustino; González-Mondragón, Edith; Betancur-Ancona, David

2016-05-01

Seeds from avocado (Persea americana Miller) fruit are a waste byproduct of fruit processing. Starch from avocado seed is a potential alternative starch source. Two different extraction solvents were used to isolate starch from avocado seeds, functional and rheological characteristics measured for these starches, and comparisons made to maize starch. Avocado seed powder was suspended in a solution containing 2 mM Tris, 7.5 mM NaCl and 80 mM NaHSO3 (solvent A) or sodium bisulphite solution (1500 ppm SO2, solvent B). Solvent type had no influence (p>0.05) on starch properties. Amylose content was 15-16%. Gelatinization temperature range was 56-74 °C, peak temperature was 65.7 °C, and transition enthalpy was 11.4-11.6J/g. At 90 °C, solubility was 19-20%, swelling power 28-30 g water/g starch, and water absorption capacity was 22-24 g water/g starch. Pasting properties were initial temperature 72 °C; maximum viscosity 380-390 BU; breakdown -2 BU; consistency 200 BU; and setback 198 BU. Avocado seed starch dispersions (5% w/v) were characterized as viscoelastic systems, with G'>G″. Avocado seed starch has potential applications as a thickening and gelling agent in food systems, as a vehicle in pharmaceutical systems and an ingredient in biodegradable polymers for food packaging. Copyright © 2016. Published by Elsevier B.V.

UPMC's blueprint for BuILDing a high-value health care system.

PubMed

Keyser, Donna; Kogan, Jane; McGowan, Marion; Peele, Pamela; Holder, Diane; Shrank, William

2018-03-30

National-level demonstration projects and real-world studies continue to inform health care transformation efforts and catalyze implementation of value-based service delivery and payment models, though evidence generation and diffusion of learnings often occurs at a relatively slow pace. Rapid-cycle learning models, however, can help individual organizations to more quickly adapt health care innovations to meet the challenges and demands of a rapidly changing health care landscape. Integrated delivery and financing systems (IDFSs) offer a unique platform for rapid-cycle learning and innovation. Since both the provider and payer benefit from delivering care that enhances the patient experience, improves quality, and reduces cost, incentives are aligned to experiment with value-based models, enhance learning about what works and why, and contribute to solutions that can accelerate transformation. In this article, we describe how the UPMC Insurance Services Division, as part of a large IDFS, uses its Business, Innovation, Learning, and Dissemination (BuILD) model to prioritize, design, test, and refine health care innovations and accelerate learning. We provide examples of how the BuILD model offers an approach for quickly assessing the impact and value of health care transformation efforts. Lessons learned through the BuILD process will offer insights and guidance for a wide range of stakeholders whether an IDFS or independent payer-provider collaborators. Copyright © 2018 Elsevier Inc. All rights reserved.

Syntheses, topological analyses, and NLO-active properties of new Cd(II)/M(II) (M = Ca, Sr) metal-organic frameworks based on R-isophthalic acids (R = H, OH, and t-Bu).

PubMed

Lin, Jian-Di; Wu, Shu-Ting; Li, Zhi-Hua; Du, Shao-Wu

2010-11-28

Solvothermal syntheses of Cd(NO(3))(2)·4H(2)O and R-isophthalic acids (R = H, OH and t-Bu) in the presence of Ca(II) or Sr(II) lead to four new three-dimensional Cd(II)/Ca(II) or Cd(II)/Sr(II) heterometallic frameworks: [CdCa(m-BDC)(2)(DMF)(2)] (1), [CdSr(2)(m-BDC)(2)(NO(3))(2)(DMF)(4)] (2), [CdCa(OH-m-BDC)(2)(H(2)O)(2)]·2Me(2)NH (3), and (Me(2)NH(2))(2)[Cd(2)Ca(Bu(t)-m-BDC)(4)] (4) (m-H(2)BDC = isophthalate, OH-m-H(2)BDC = 5-hydroxyisophthalate and Bu(t)-m-H(2)BDC = 5-butylisophthalate). All of these compounds except for 4 crystallize in acentric (or chiral) space groups and the bulk materials for 1 and 3 display strong powder SHG efficiencies, approximately 1.54 and 2.31 times than that of a potassium dihydrogen phosphate (KDP) powder. Topological analyses show that 1 and 2 have structures with sxb and dia topologies, respectively, while both 3 and 4 exhibit pcu topological nets when the metal carboxylate clusters are viewed as nodes. The fluorescence properties and thermal stabilities for these compounds are also investigated.

The puzzle of Buruli ulcer transmission, ethno-ecological history and the end of "love" in the Akonolinga district, Cameroon.

PubMed

Giles-Vernick, Tamara; Owona-Ntsama, Joseph; Landier, Jordi; Eyangoh, Sara

2015-03-01

The "One World One Health Initiative" has attended little to the priorities, concepts and practices of resource-poor communities confronting disease and the implications of these concerns for its biomedical, ecological and institutional approach to disease surveillance and control. Using the example of Buruli ulcer (BU) and its bacterial etiology, Mycobacterium ulcerans, in south-central Cameroon, we build on debates about the contributions of "local knowledge" and "alternative models" to biomedical knowledge of disease transmission. BU's mode of transmission remains poorly understood. Our approach employs ethno-ecological histories - local understandings of the putative emergence and expansion of a locally important, neglected disease. We develop these histories from 52 individual and small group interviews, group discussions, and participant-observation of daily and seasonal activities, conducted in 2013-2013. These histories offer important clues about past environmental and social change that should guide further ecological, epidemiological research. They highlight a key historical moment (the late 1980s and 1990s); specific ecological transformations; new cultivation practices in unexploited zones that potentially increased exposure to M. ulcerans; and ecological degradation that may have lowered nutritional standards and heightened susceptibility to BU. They also recast transmission, broadening insight into BU and its local analog, atom, by emphasizing the role of social change and economic crisis in its emergence and expansion. Copyright © 2014 Elsevier Ltd. All rights reserved.

Titanium isopropoxide complexes of a series of sterically demanding aryloxo based [N2O2]2- ligands as precatalysts for ethylene polymerization.

PubMed

Panda, Manas K; Kaur, Sukhdeep; Reddy, Annapureddy Rajasekhar; Shaikh, Mobin M; Butcher, Ray J; Gupta, Virendrakumar; Ghosh, Prasenjit

2010-12-07

Several titanium isopropoxide complexes [N,N'-bis(2-oxo-3-R(1)-5-R(2)-phenylmethyl)-N,N'-bis(methylene-p-R(3)-C(6)H(4))-ethylenediamine]Ti(O(i)Pr)(2) [R(1) = t-Bu, R(2) = Me, R(3) = H (1b); R(1) = R(2) = t-Bu, R(3) = H, (2b); R(1) = R(2) = Cl, R(3) = H, (3b), R(1) = t-Bu, R(2) = Me, R(3) = Cl (4b); R(1) = R(2) = t-Bu, R(3) = Cl, (5b); R(1) = R(2) = R(3) = Cl, (6b)] supported over sterically demanding aryloxy based [N(2)O(2)]H(2) ligands have been designed as precatalysts for the ethylene polymerization. Specifically, the 1b-6b complexes, when treated with methylaluminoxane (MAO) under 88 ± 0.5 psi of ethylene at 30 °C for 3 h, produced polyethylene polymers of high molecular weight (M(w) = ca. 7.2-8.3 × 10(5) g mol(-1)) having broad molecular weight distribution (PDI = ca. 13.1-14.6). The 1b-6b complexes were conveniently synthesized from the direct reaction of the [N(2)O(2)]H(2) ligands, 1a-6a, with Ti(O(i)Pr)(4) in 69-86% yield.

Synthesis, spectral and antifungal analysis of diaryldithiophosphates of mono- and dibutyltin(IV): x-ray structure of [{(3,5-CH3)2C6H3O)2PS2}2Sn(nBu)2].

PubMed

Syed, Atiya; Khajuria, Ruchi; Kumar, Sandeep; Jassal, Amanpreet Kaur; Hundal, Maninder S; Pandey, Sushil K

2014-01-01

Diaryldithiophosphate complexes of mono- and dibutyltin(IV) corresponding to [(ArO)(2)PS(2)(n)Sn(nBu)xCl(4-x-n)] (Ar = o-CH(3)C(6)H(4), m-CH(3)C(6)H(4), p-CH(3)C(6)H(4), 4-Cl-3-CH(3)C(6)H(3), (3,5-CH(3))(2)C(6)H(3); n = 1, 2 for x = 1 and n = 2 for x = 2) were successfully isolated and characterized by elemental analyses, IR, multinuclear NMR ((1)H, (13)C, (31)P and (119)Sn) spectroscopy and X-ray analysis. The thermal properties of the complex [(3,5-CH(3))(2)C(6)H(3)O(2)PS(2)](2)Sn(nBu)(2) (12) have been examined by combined DTA/ DTG thermal analyses. Single crystal X-ray analysis of [(3,5-CH(3))(2)C(6)H(3)O(2)PS(2)](2)S(n)(nBu)(2) (12) revealed that two diaryldithiophosphate ions are coordinated to tin atom in an anisobidentate fashion through the sulfur atoms of each dithiophosphate moiety leading to distorted skew-trapezoidal bipyramidal geometry. The antifungal activity depicts that these complexes are active against fungus Penicillium chrysogenium.

Global dysrhythmia of cerebro-basal ganglia-cerebellar networks underlies motor tics following striatal disinhibition.

PubMed

McCairn, Kevin W; Iriki, Atsushi; Isoda, Masaki

2013-01-09

Motor tics, a cardinal symptom of Tourette syndrome (TS), are hypothesized to arise from abnormalities within cerebro-basal ganglia circuits. Yet noninvasive neuroimaging of TS has previously identified robust activation in the cerebellum. To date, electrophysiological properties of cerebellar activation and its role in basal ganglia-mediated tic expression remain unknown. We performed multisite, multielectrode recordings of single-unit activity and local field potentials from the cerebellum, basal ganglia, and primary motor cortex using a pharmacologic monkey model of motor tics/TS. Following microinjections of bicuculline into the sensorimotor putamen, periodic tics occurred predominantly in the orofacial region, and a sizable number of cerebellar neurons showed phasic changes in activity associated with tic episodes. Specifically, 64% of the recorded cerebellar cortex neurons exhibited increases in activity, and 85% of the dentate nucleus neurons displayed excitatory, inhibitory, or multiphasic responses. Critically, abnormal discharges of cerebellar cortex neurons and excitatory-type dentate neurons mostly preceded behavioral tic onset, indicating their central origins. Latencies of pathological activity in the cerebellum and primary motor cortex substantially overlapped, suggesting that aberrant signals may be traveling along divergent pathways to these structures from the basal ganglia. Furthermore, the occurrence of tic movement was most closely associated with local field potential spikes in the cerebellum and primary motor cortex, implying that these structures may function as a gate to release overt tic movements. These findings indicate that tic-generating networks in basal ganglia mediated tic disorders extend beyond classical cerebro-basal ganglia circuits, leading to global network dysrhythmia including cerebellar circuits.

Synchronous onset of the Messinian evaporite precipitation: First Mediterranean offshore evidence

NASA Astrophysics Data System (ADS)

Ochoa, Diana; Sierro, Francisco J.; Lofi, Johanna; Maillard, Agnès; Flores, Jose-Abel; Suárez, Mercedes

2015-10-01

The Messinian Salinity Crisis (MSC) was a major ecological crisis affecting shallow and deep-water settings over the entire Mediterranean basin. However, the evolution of the MSC and its ecological impacts have mainly been explained on the basis of sediments from onshore outcrops. Lack of complete and physically connected records from onshore and offshore settings has inhibited comprehensive understanding of basin behaviour during the MSC. Herein we present a continuous record from an intermediate-depth basin on the Balearic Promontory that comprises late Tortonian-Messinian marls and evaporitic beds from the first MSC phase (i.e., Primary Lower Gypsum-PLG stage). Well-log and biostratigraphic data allow us establishing a large-scale calibration to the astronomical solutions, and to correlate pre-MSC sediments with classical rhythmic successions outcropping onshore. Thickness and characteristic sedimentary patterns observed in the offshore evaporitic records resemble those from marginal PLG sequences. Furthermore, seismic reflectors from a Bedded Unit (BU), which corresponds to an evaporitic interval according to well-to-seismic ties, are correlated with the onshore PLG sequences. This correlation constitutes the first attempt to link well-known marginal sequences with intermediate-depth offshore settings, which have previously only been studied through seismic imaging. Our time-calibration provides direct evidence supporting a synchronous onset of the PLG phase between onshore and offshore settings along the southwestern Balearic Promontory margin. Those BU reflectors, which were positively correlated to the PLG, were likely precipitated offshore the continental shelf at Messinian times. These results suggest that gypsum precipitation and/or preservation was not always limited to 200 m water-depths and could occur in non-silled basins. Finally, we only found a major erosion at the top of the PLG sequences, implying that the MSC drawdown occurred after the precipitation of the onshore lower evaporites. Studied sequences provide new insights into the PLG precipitation/preservation settings, as well as into the land-sea correlations of MSC units, and thus could potentially help refine current MSC models.

3D stratigraphic forward modelling of Shu'aiba Platform stratigraphy in the Bu Hasa Field, Abu Dhabi, United Arab Emirates.

NASA Astrophysics Data System (ADS)

Hu, J.; Lokier, S. W.

2012-04-01

This paper presents the results of three dimensional sequence stratigraphic forward modelling of the Aptian age Shu'aiba Formation from Abu Dhabi, United Arab Emirates (UAE). The Shu'aiba Formation lies within the uppermost part of the Lower Cretaceous Thamama Group and forms one of the most prolific hydrocarbon reservoir intervals of the Middle East with production dating back to the 1960's. The Shu'aiba Formation developed as a series of laterally-extensive shallow-water carbonate platforms in an epeiric sea that extended over the northern margin of the African-Arabian Plate. This shallow sea was bounded by the Arabian Shield to the west and the passive margin with the Neo-Tethys Ocean towards the north and east (Droste, 2010). The exposed Arabian Shield acted as a source of siliciclastic sediments to westernmost regions, however, more offshore areas were dominated by shallow-water carbonate deposition. Carbonate production was variously dominated by Lithocodium-Baccinella, orbitolinid foraminifera and rudist bivalves depending on local conditions. While there have been numerous studies of this important stratigraphic interval (for examples see van Buchem et al., 2010), there has been little attempt to simulate the sequence stratigraphic development of the formation. During the present study modelling was undertaken utilising the CARBONATE-3D stratigraphic forward modelling software (Warrlich et al., 2008; Warrlich et al., 2002)) thus allowing for the control of a diverse range of internal and external parameters on carbonate sequence development. This study focuses on platform development in the onshore Bu Hasa Field - the first giant oilfield to produce from the Shu'aiba Formation in Abu Dhabi. The carbonates of the Bu Hasa field were deposited on the southwest slope of the intra-shelf Bab Basin, siliciclastic content is minor. Initially these carbonates were algal dominated with rudist mounds becoming increasingly important over time (Alsharhan, 1987). Numerous simulations were undertaken, employing different sea level curves, platform geometries, etc. in order to accurately constrain and compare simulated facies geometries with those hypothesised from subsurface correlations. An initial low-angle ramp geometry was later overprinted by the development of localised relief through faulting and salt diapirism. Areas of bathymetric relief became sites of enhanced carbonate development with over-production resulting in aggradational geometries rapidly evolving to progradational systems. Several different regional, global and composite relative sea level curves were employed in the simulations in order to produce stratigraphic geometries comparable to those reported from previous studies. We conclude that none of the published sea level curves produce facies geometries directly analogous to those hypothesised from the sub-surface. We infer that this disparity primarily results from previous models lacking sufficient accommodation space and employing unrealistic carbonate production rates.

Synthesis, structural investigations on organotin(IV) chlorin-e6 complexes, their effect on sea urchin embryonic development and induced apoptosis.

PubMed

Pellerito, Claudia; D'Agati, Paolo; Fiore, Tiziana; Mansueto, Caterina; Mansueto, Valentina; Stocco, Giancarlo; Nagy, László; Pellerito, Lorenzo

2005-06-01

Four new organotin(IV) chlorin derivatives, [chlorin=chlorin-e(6)=21H,23H-porphine-2-propanoic acid, 18-carboxy-20-(carboxymethyl)-8-ethenyl-13-ethyl-2,3-di-hydro-3,7,12,17-tetramethyl-(2S-trans)-], with formula (R(2)Sn)(3)(chlorin)(2).2H(2)O (R=Me, n-Bu) and (R(3)Sn)(3)chlorin.2H(2)O (R=Me, Ph) have been synthesized. The solid state and solution phase structures have been investigated by FT-IR, (119)Sn Mössbauer, (1)H and (13)C NMR spectroscopy. In the solid state, (R(2)Sn)(3)(chlorin)(2).2H(2)O complexes contain six coordinated Sn(IV), in a skew trapezoidal environment by forming trans-R(2)SnO(4) polymeric units. As far as (R(3)Sn)(3)chlorin.2H(2)O complexes are concerned, Sn(IV) is five coordinated in a polymeric (oligomeric) trigonal bipyramidal environment and eq-R(3)SnO(2) units, in the solid state. In saturated solutions, a polymeric structure comparable to the solid phase, with carboxylate groups of the ligand behaving in monoanionic bidentate fashion bridging Sn(IV) atoms, was detected for the (Me(3)Sn)(3)chlorin.2H(2)O complex, while in more diluted ones a tetrahedral configuration for the trimethyltin(IV) moieties was observed. Cytotoxic activity of the novel organotin(IV) chlorin was investigated in order to assay the effect on sea urchin embryonic development. The results obtained demonstrated that (n-Bu(2)Sn)(3)(chlorin)(2).2H(2)O and (Ph(3)Sn)(3)chlorin.2H(2)O exerted the antimitotic effect on the early stages of sea urchin development. In addition, the cytotoxic effect exerted by (n-Bu(2)Sn)(3)(chlorin)(2).2H(2)O appeared with necrosis of the blastomeres, which were clearly destroyed. After treatment with (Ph(3)Sn)(3)chlorin.2H(2)O, a programmed cell death was triggered, as shown by light microscope observations through morphological assays. The apoptotic events in 2-cell stage embryos revealed: (i) DNA fragmentation, with the TUNEL reaction (terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling); (ii) phosphatidylserine translocation in the membrane, with Annexin-V assay and (iii) cytoplasm blebbing, with the TUNEL reaction. The results demonstrated that the novel compound (Ph(3)Sn)(3)chlorin.2H(2)O was the most toxic derivative, by exerting antimitotic effect very early and by triggering apoptosis in the 2-cell stage of sea urchin embryonic development.

Striatal dysfunction increases basal ganglia output during motor cortex activation in parkinsonian rats.

PubMed

Belluscio, Mariano A; Riquelme, Luis A; Murer, M Gustavo

2007-05-01

During movement, inhibitory neurons in the basal ganglia output nuclei show complex modulations of firing, which are presumptively driven by corticostriatal and corticosubthalamic input. Reductions in discharge should facilitate movement by disinhibiting thalamic and brain stem nuclei while increases would do the opposite. A proposal that nigrostriatal dopamine pathway degeneration disrupts trans-striatal pathways' balance resulting in sustained overactivity of basal ganglia output nuclei neurons and Parkinson's disease clinical signs is not fully supported by experimental evidence, which instead shows abnormal synchronous oscillatory activity in animal models and patients. Yet, the possibility that variation in motor cortex activity drives transient overactivity in output nuclei neurons in parkinsonism has not been explored. In Sprague-Dawley rats with 6-hydroxydopamine (6-OHDA)-induced nigrostriatal lesions, approximately 50% substantia nigra pars reticulata (SNpr) units show abnormal cortically driven slow oscillations of discharge. Moreover, these units selectively show abnormal responses to motor cortex stimulation consisting in augmented excitations of an odd latency, which overlapped that of inhibitory responses presumptively mediated by the trans-striatal direct pathway in control rats. Delivering D1 or D2 dopamine agonists into the striatum of parkinsonian rats by reverse microdialysis reduced these abnormal excitations but had no effect on pathological oscillations. The present study establishes that dopamine-deficiency related changes of striatal function contribute to producing abnormally augmented excitatory responses to motor cortex stimulation in the SNpr. If a similar transient overactivity of basal ganglia output were driven by motor cortex input during movement, it could contribute to impeding movement initiation or execution in Parkinson's disease.

[New hypothesis on the replication of centrioles and basal bodies].

PubMed

Mignot, J P

1996-12-01

Certain morphological data, obtained in studies of the ultrastructure of centrioles and basal bodies in cells of metazoa and protists, lead us to think that the cartwheel represents of the most appropriate organization for a self-reproducing and transmissible centriolar organizer. Centrioles and basal bodies might then not be simply the centres of replication of those organizers, but also reservoirs containing several superposed centriolar organizers, which are released depending on the requirements of the cell. As an isolated cartwheel is extremely unlikely to be detected, either in conventional electron microscopy or in immunocytochemistry, it is thus the reservoir which has so far been under consideration. Such a hypothesis would permit the explanation that biogenesis de novo and biogenesis in proximity to preexisting organelles may differ only in terms of the number of morphogenetic units involved.

Open-Shell Lanthanide(II+) or -(III+) Complexes Bearing σ-Silyl and Silylene Ligands: Synthesis, Structure, and Bonding Analysis

PubMed Central

2015-01-01

Complexes featuring lanthanide (Ln)–Si bonds represent a highly neglected research area. Herein, we report a series of open-shell LnII+ and LnIII+ complexes bearing σ-bonded silyl and base-stabilized N-heterocyclic silylene (NHSi) ligands. The reactions of the LnIII+ complexes Cp3Ln (Ln = Tm, Ho, Tb, Gd; Cp = cyclopentadienide) with the 18-crown-6 (18-cr-6)-stabilized 1,4-oligosilanyl dianion [(18-cr-6)KSi(SiMe3)2SiMe2SiMe2Si(SiMe3)2K(18-cr-6)] (1) selectively afford the corresponding metallacyclopentasilane salts [Cp2Ln({Si(SiMe3)2SiMe2}2)]−[K2(18-cr-6)2Cp]+ [Ln = Tm (2a), Ho (2b), Tb (2c), Gd (2d)]. Complexes 2a–2d represent the first examples of structurally characterized Tm, Ho, Tb, and Gd complexes featuring Ln–Si bonds. Strikingly, the analogous reaction of 1 with the lighter element analogue Cp3Ce affords the acyclic product [Cp3CeSi(SiMe3)2SiMe2SiMe2Si(SiMe3)2-Cp3Ce]2–2[K(18-cr-6)]+ (3) as the first example of a complex featuring a Ce–Si bond. In an alternative synthetic approach, the aryloxy-functionalized benzamidinato NHSi ligand Si(OC6H4-2-tBu){(NtBu)2CPh} (4a) and the alkoxy analogue Si(OtBu){(NtBu)2CPh} (4b) were reacted with Cp*2Sm(OEt2), affording, by OEt2 elimination, the corresponding silylene complexes, both featuring SmII+ centers: Cp*2Sm ← :Si(O–C6H4-2-tBu){(NtBu)2CPh} (6) and Cp*2Sm ← :Si(OtBu){(NtBu)2CPh} (5). Complexes 5 and 6 are the first four-coordinate silylene complexes of any f-block element to date. All complexes were fully characterized by spectroscopic means and by single-crystal X-ray diffraction analysis. In the series 2a–2d, a linear correlation was observed between the Ln–Si bond lengths and the covalent radii of the corresponding Ln metals. Moreover, in complexes 5 and 6, notably long Sm–Si bonds are observed, in accordance with a donor–acceptor interaction between Si and Sm [5, 3.4396(15) Å; 6, 3.3142(18) Å]. Density functional theory calculations were carried out for complexes 2a–2d, 5, and 6 to elucidate the bonding situation between the LnII+ or LnIII+ centers and Si. In particular, a decrease in the Mayer bond order (MBO) of the Ln–Si bond is observed in the series 2a–2d in moving from the lighter to the heavier lanthanides (Tm = 0.53, Ho = 0.62, Tb = 0.65, and Gd = 0.75), which might indicate decreasing covalency in the Ln–Si bond. In accordance with the long bond lengths observed experimentally in complexes 5 and 6, comparatively low MBOs were determined for both silylene complexes (5, 0.24; 6, 0.25) . PMID:25756230

Synthesis, structure, and magnetic characterization of a C3-symmetric Mn(III)3Cr(III) assembly: molecular recognition between a trinuclear Mn(III) triplesalen complex and a fac-triscyano Cr(III) complex.

PubMed

Freiherr von Richthofen, Carl-Georg; Stammler, Anja; Bögge, Hartmut; DeGroot, Marty W; Long, Jeffrey R; Glaser, Thorsten

2009-11-02

The reaction of the tris(tetradentate) triplesalen ligand H(6)talen(t-Bu(2)), which provides three salen-like coordination environments bridged in a meta-phenylene arrangement by a phloroglucinol backbone, with Mn(II) salts under aerobic conditions, affords, in situ, the trinuclear Mn(III) triplesalen complex [(talen(t-Bu(2))){Mn(III)(solv)(n)}(3)](3+). This species then reacts with [(Me(3)tacn)Cr(CN)(3)] to form the tetranuclear complex [{(talen(t-Bu(2)))Mn(III)(3)}{(Me(3)tacn)Cr(CN)(3)}](3+) ([Mn(III)(3)Cr(III)](3+)). The regular ligand folding observed in the trinuclear triplesalen complex preorganizes the three metal ions for the reaction with three facially coordinated nitrogen atoms of [(Me(3)tacn)Cr(CN)(3)]. [{(talen(t-Bu(2)))(Mn(III)(MeOH))(3)}{(Me(3)tacn)Cr(CN)(3)}](ClO(4))(3) (1) was characterized by infrared spectroscopy, elemental analysis, mass spectrometry, electron absorption spectroscopy, and magnetic measurements. The molecular structure was established for the acetate-substituted derivative [{(talen(t-Bu(2)))(Mn(III)(MeOH))(2)(Mn(III)(OAc))}{(Me(3)tacn)Cr(CN)(3)}](ClO(4))(2) (2) by single-crystal X-ray diffraction. Variable-temperature-variable-field and mu(eff) versus T magnetic data have been analyzed in detail by full-matrix diagonalization of the appropriate spin-Hamiltonian, consisting of isotropic exchange, zero-field splitting, and Zeeman interaction components. Satisfactory reproduction of the experimental data has been obtained for the parameters J(Mn-Cr) = -0.12 +/- 0.04 cm(-1), J(Mn-Mn) = -0.70 +/- 0.03 cm(-1), and D(Mn) = -3.0 +/- 0.4 cm(-1). These generate a triply degenerate pseudo S(t) = 7/2 spin manifold, which cannot be appropriately described by a giant spin model and which exhibits a weak easy-axis magnetic anisotropy. This is corroborated by the onset of a frequency-dependent chi'' signal at low temperatures, demonstrating a slow relaxation of the magnetization indicative of 1 being a single-molecule magnet. Comparing the properties to those of the heptanuclear analogue [{(talen(t-Bu(2)))Mn(III)(3)}(2){Cr(III)(CN)(6)}](3+) ([Mn(III)(6)Cr(III)](3+)) formed by the reaction of 2 equiv of [(talen(t-Bu(2))){Mn(III)(solv)(n)}(3)](3+) with 1 equiv of [Cr(CN)(6)](3-) [Glaser, T.; Heidemeier, M.; Weyhermüller, T.; Hoffmann, R.-D.; Rupp, H.; Müller, P. Angew. Chem. Int. Ed., 2006, 45, 6033-6037] demonstrates a lower driving force for formation, a strongly reduced J(Mn-Cr) exchange, a slightly reduced J(Mn-Mn) exchange, and a significantly longer Mn-N(N[triple bond]C) bond length in [Mn(III)(3)Cr(III)](3+). Taking into account magneto-structural correlations establishes a supramolecular interaction between the two [(talen(t-Bu(2)))Mn(III)(3)](3+) subunits in [Mn(III)(6)Cr(III)](3+) responsible for the structural distortion and the short Mn-N(N[triple bond]C) distance which results in a strong J(Mn-Cr) exchange and thus [Mn(III)(6)Cr(III)](3+) being a single-molecule magnet with a relatively high effective anisotropy barrier of 25.4 K.

Di and trinuclear rare-earth metal complexes supported by 3-amido appended indolyl ligands: synthesis, characterization and catalytic activity towards isoprene 1,4-cis polymerization.

PubMed

Zhang, Guangchao; Deng, Baojia; Wang, Shaowu; Wei, Yun; Zhou, Shuangliu; Zhu, Xiancui; Huang, Zeming; Mu, Xiaolong

2016-10-21

Different di and trinuclear rare-earth metal complexes supported by 3-amido appended indolyl ligands were synthesized and their catalytic activities towards isoprene polymerization were investigated. Treatment of [RE(CH 2 SiMe 3 ) 3 (thf) 2 ] with 1 equiv. of 3-(CyN[double bond, length as m-dash]CH)C 8 H 5 NH in toluene or in THF afforded dinuclear rare-earth metal alkyl complexes having indolyl ligands in different hapticities with central metals {[η 2 :η 1 -μ-η 1 -3-(CyNCH(CH 2 SiMe 3 ))Ind]RE-(thf)(CH 2 SiMe 3 )} 2 (Cy = cyclohexyl, Ind = Indolyl, RE = Yb (1), Er (2), Y (3)) or {[η 1 -μ-η 1 -3-(CyNCH(CH 2 SiMe 3 ))Ind]RE-(thf) 2 (CH 2 SiMe 3 )} 2 (RE = Yb (4), Er (5), Y (6), Gd (7)), respectively. These two series of dinuclear complexes could be transferred to each other easily by only changing the solvents in the process. Reaction of [Er(CH 2 SiMe 3 ) 3 (thf) 2 ] with 1 equiv. of 3-t-butylaminomethylindole 3-( t BuNHCH 2 )C 8 H 5 NH in THF afforded the unexpected trinuclear erbium alkyl complex [η 2 :η 1 -μ-η 1 -3-( t BuNCH 2 )Ind] 4 Er 3 (thf) 5 (CH 2 SiMe 3 ) (8), which can also be prepared by reaction of 3 equiv. of [Er(CH 2 SiMe 3 ) 3 (thf) 2 ] with 4 equiv. of 3-( t BuNHCH 2 )C 8 H 5 NH in THF. Accordingly, complexes [η 2 :η 1 -μ-η 1 -3-( t BuNCH 2 )Ind] 4 RE 3 (thf) 5 (CH 2 SiMe 3 ) (RE = Y (9), Dy (10)) were prepared by reactions of 3 equiv. of [RE(CH 2 SiMe 3 ) 3 (thf) 2 ] with 4 equiv. of 3-( t BuNHCH 2 )C 8 H 5 NH in THF. Reactions of [RE(CH 2 SiMe 3 ) 3 (thf) 2 ] with 1 equiv. of 3-t-butylaminomethylindole 3-( t BuNHCH 2 )C 8 H 5 NH in THF, followed by treatment with 1 equiv. of [(2,6- i Pr 2 C 6 H 3 )N[double bond, length as m-dash]CHNH(C 6 H 3 i Pr 2 -2,6)] afforded, after workup, the dinuclear rare-earth metal complexes [η 1 -μ-η 1 :η 1 -3-( t BuNCH 2 )Ind][η 1 -μ-η 1 :η 3 -3-( t BuNCH 2 )Ind]RE 2 (thf)[(η 3 -2,6- i Pr 2 C 6 H 3 )NCHN(C 6 H 3 i Pr 2 -2,6)] 2 (RE = Er (11), Y (12)) having the indolyl ligands bonded with the rare-earth metal in different ligations. All new complexes 1-12 were fully characterized by spectroscopic methods and elemental analyses, and their structures were determined by X-ray crystallographic analyses. It was found that, except for complexes 1, 4, 11 and 12, all complexes were highly efficient catalysts for selective isoprene polymerization (up to 99% 1,4-cis selectivity) with the cooperation of co-catalysts, and the trinuclear complexes displayed advantages over dinuclear complexes in terms of molecular weight of polymers.

Osmium(III) analogues of KP1019: electrochemical and chemical synthesis, spectroscopic characterization, X-ray crystallography, hydrolytic stability, and antiproliferative activity.

PubMed

Kuhn, Paul-Steffen; Büchel, Gabriel E; Jovanović, Katarina K; Filipović, Lana; Radulović, Siniša; Rapta, Peter; Arion, Vladimir B

2014-10-20

A one-electron reduction of osmium(IV) complexes trans-[Os(IV)Cl4(Hazole)2], where Hazole = 1H-pyrazole ([1](0)), 2H-indazole ([2](0)), 1H-imidazole ([3](0)), and 1H-benzimidazole ([4](0)), afforded a series of eight new complexes as osmium analogues of KP1019, a lead anticancer drug in clinical trials, with the general formula (cation)[trans-Os(III)Cl4(Hazole)2], where cation = H2pz(+) (H2pz[1]), H2ind(+) (H2ind[2]), H2im(+) (H2im[3]), Ph4P(+) (Ph4P[3]), nBu4N(+) (nBu4N[3]), H2bzim(+) (H2bzim[4]), Ph4P(+) (Ph4P[4]), and nBu4N(+) (nBu4N[4]). All complexes were characterized by elemental analysis, (1)H NMR spectroscopy, electrospray ionization mass spectrometry, UV-vis spectroscopy, cyclic voltammetry, while H2pz[1], H2ind[2], and nBu4[3], in addition, by X-ray diffraction. The reduced species [1](-) and [4](-) are stable in aqueous media in the absence of air oxygen and do not react with small biomolecules such as amino acids and the nucleotide 5'-dGMP. Cell culture experiments in five different human cancer cell lines (HeLa, A549, FemX, MDA-MB-453, and LS-174) and one noncancerous cell line (MRC-5) were performed, and the results were discussed and compared to those for KP1019 and cisplatin. Benzannulation in complexes with similar structure enhances antitumor activity by several orders of magnitude, implicating different mechanisms of action of the tested compounds. In particular, complexes H2ind[2] and H2bzim[4] exhibited significant antiproliferative activity in vitro when compared to H2pz[1] and H2im[3].

In vitro and ex vivo anticholinesterase activities of Erythrina velutina leaf extracts.

PubMed

Santos, Wanderson Praxedes; da Silva Carvalho, Ana Carla; dos Santos Estevam, Charles; Santana, Antônio Euzébio Goulart; Marçal, Rosilene Moretti

2012-07-01

Erythrina velutina (EV) Willd (Fabaceae-Faboideae) is a medicinal tree that is commonly used in Brazil for the treatment of several central nervous system disorders. The anticholinesterase activity of EV is described in this work. Concentration-response curves (0-1.6 mg/mL) for EV leaf aqueous extract (AE) and alkaloid-rich extracts (AKEs) were performed in vitro. Cholinesterase inhibition was examined in mouse brains, as the cholinesterase source, and in pure acetylcholinesterase (AChE) or butyrylcholinesterase (BuChE). Mice were treated with AE or AKE (100, 200, and 400 mg/kg, p.o.) and their brains were used for the measurement of cholinesterase activity (CA) ex vivo. CA was inhibited by AE (IC(50) = 0.57 [0.43-0.75] mg/mL) and AKE (IC(50) = 0.52 [0.39-0.70] mg/mL) in brain homogenates in a concentration-dependent manner. The ex vivo experiments indicated that AE (400 mg/kg, p < 0.05, 32.2 ± 3.9% of inhibition) and AKE (all doses: p < 0.05-p < 0.001, 29.6 ± 3.2% as the maximum inhibition) significantly inhibited CA in the central nervous system after oral administration. AE and AKE inhibited AChE and BuChE activities in a concentration-dependent manner (AE: IC(50AChE) = 0.56 [0.38-0.81] mg/mL, IC(50BuChE) = 2.95 [1.51-5.76] mg/mL, AKE: IC(50AChE) = 0.87 [0.60-12.5] mg/mL, IC(50BuChE) = 2.67 [0.87-8.11] mg/mL). These data indicated that AE and AKE crossed the blood-brain barrier to inhibit CA in the brain. AE and AKE also exhibited a dual inhibitory action on acetyl- and BuChE.

O-H bond dissociation enthalpies in oximes: order restored.

PubMed

Pratt, Derek A; Blake, Jessie A; Mulder, Peter; Walton, John C; Korth, Hans-Gert; Ingold, Keith U

2004-09-01

The O-H bond dissociation enthalpies (BDEs) of 13 oximes, RR'C=NOH, having R and/or R' = H, alkyl, and aryl are reported. Experimental anchor points used to validate the results of theoretical calculations include (1) the O-H BDEs of (t-Bu)2C=NOH, t-Bu(i-Pr)C=NOH, and t-Bu(1-Ad)C=NOH determined earlier from the heat released in the reaction of (t-Bu)2C=NO* with (PhNH)2 in benzene and EPR spectroscopy (Mahoney, L. R.; Mendenhall, G. D.; Ingold, K. U. J. Am. Chem. Soc. 1973, 95, 8610), all of which were decreased by 1.7 kcal/mol to reflect a revision to the heat of formation of (E)-azobenzene (which has significant ramifications for other BDEs) and to correct for the heat of hydrogen bonding of (t-Bu)2C=NOH (alphaH2 = 0.43 measured in this work) to benzene, and (2) the measured rates of thermal decomposition of six RR'C=NOCH2Ph at 423 or 443 K, which were used to derive O-H BDEs for the corresponding RR'C=NOH. Claims (Bordwell, F. G.; Ji, G. Z. J. Org. Chem. 1992, 57, 3019; Bordwell, F. G.; Zhang, S. J. Am. Chem. Soc. 1995, 117, 4858; and Bordwell, F. G.; Liu, W.-Z. J. Am. Chem. Soc. 1996, 118, 10819) that the O-H BDEs in mono- and diaryloximes are significantly lower than those for alkyloximes due to delocalization of the unpaired electron into the aromatic ring have always been inconsistent with the known structures of iminoxyl radicals as are the purported perpendicular structures, i.e., phi(Calpha-C=N-O*) = 90 degrees, for sterically hindered dialkyl iminoxyl radicals. The present results confirm the 1973 conclusion that simple steric effects, not electron delocalization or dramatic geometric changes, are responsible for the rather small differences in oxime O-H BDEs. Copyright 2004 American Chemical Society

Steric/π-electronic insulation of the carbo-benzene ring: dramatic effects of tert-butyl vs phenyl crowns on geometric, chromophoric, redox and magnetic properties.

PubMed

Listunov, Dymytrii; Duhayon, Carine; Poater, Albert; Mazères, Serge; Saquet, Alix; Maraval, Valérie; Chauvin, Remi

2018-04-13

Hexa-tert-butyl-carbo-benzene C18tBu6 and three phenylated counterparts C18tBumPh6-m (m = 4, 2) have been synthesized. The peralkylated version (m = 6) provides experimental access to intrinsic features of the insulated C18 core independently from the influence of π-conjugated substituent. Over the series, structural, spectroscopical and electrochemical properties are compared with those of the hexaphenylated reference (m = 0). Anchoring tBu substituents at the C18 macrocycle is shown to enhance stability and solubility, and to dramatically modify UV-vis absorption and redox properties. Whereas all the carbo-benzenes reported hitherto were obtained as dark-reddish/greenish solids, crystals and solutions of C18tBu6 happen to be yellow (max = 379 nm vs 472 nm for C18Ph6). By comparison to C18Ph6, reduction of C18tBu6 remains reversible but occurs at a twice higher absolute potential (E1/2 = -1.36 V vs -0.72 V). Systematic X-ray diffraction analyses and DFT calculations show that the C18 ring symmetry is the nearest to D6h for m = 6, indicating a maximum geometrical aromaticity. According to calculated nucleus independent chemical shifts, the macrocyclic magnetic aromaticity is also found to be maximum for C18tBu6: NICS(0)=-17.2 ppm, vs -18.0±0.1 ppm for the theoretical references C18H6 and C18F6, and -13.5 ppm for C18Ph6. Accurate correlations of NICS(0) with experimental or calculated maximum UV-vis absorption wavelength max and chemical hardness =ELUMO-EHOMO are evidenced. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Assessment of water, sanitation, and hygiene practices and associated factors in a Buruli ulcer endemic district in Benin (West Africa).

PubMed

Johnson, Roch Christian; Boni, Gratien; Barogui, Yves; Sopoh, Ghislain Emmanuel; Houndonougbo, Macaire; Anagonou, Esai; Agossadou, Didier; Diez, Gabriel; Boko, Michel

2015-08-19

Control of neglected tropical diseases (NTDs) requires multiple strategic approaches including water, sanitation and hygiene services (WASH). Buruli ulcer (BU), one of the 17 NTDs, remains a public health issue in Benin particularly in the district of Lalo. The availability of water as well as good hygiene are important for the management of Buruli ulcer particularly in the area of wound care one of the main component of the treatment of BU lesions. Given the growing importance of WASH in controlling NTDs and in order to assess the baseline for future cross-cutting interventions, we report here on the first study evaluating the level of WASH and associated factors in Lalo, one of the most BU-endemic districts in Benin. A cross-sectional study was carried to assess WASH practices and associated factors in the district of Lalo. Data were collected from 600 heads of household using structured pretested questionnaire and observations triangulated with qualitative information obtained from in-depth interviews of patients, care-givers and community members. Univariate and multivariate analysis were carried to determine the relationships between the potential associated factors and the sanitation as well as hygiene status. BU is an important conditions in the district of Lalo with 917 new cases detected from 2006 to 2012. More than 49 % of the household surveyed used unimproved water sources for their daily needs. Only 8.7 % of the investigated household had improved sanitation facilities at home and 9.7 % had improved hygiene behavior. The type of housing as an indicator of the socioeconomic status, the permanent availability of soap and improved hygiene practices were identified as the main factors positively associated with improved sanitation status. In the district of Lalo in Benin, one of the most endemic for BU, the WASH indicators are very low. This study provides baseline informations for future cross-cutting interventions in this district.

Characterization of the In Vitro Kinetic Interaction of Chlorpyrifos-Oxon with Rat Salivary Cholinesterase: A Potential Biomonitoring Matrix

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kousba, Ahmed A.; Poet, Torka S.; Timchalk, Charles

2003-02-12

Chlorpyrifos (CPF) is a commonly used organophosphate insecticide (OP). The primary mechanism of action for CPF involves the inhibition of acetylcholinesterase (AChE) by the active metabolite, CPF-oxon, with subsequent accumulation of acetylcholine (ACh) resulting in a wide range of neutotoxicity. CPF-oxon, can likewise inhibit other non-target cholinesterases (ChE) such as butyrylcholinesterase (BuChE), which represents a detoxification mechanism and a potential biomarker of exposure/response. Biological monitoring for OPs has focused on measuring parent chemical or metabolite in blood and urine or blood ChE inhibition. Salivary biomonitoring has recently been explored as a practical method for examination of chemical exposure; however, theremore » are a limited number of studies exploring its use for OPs. To evaluate the use of salivary ChE as a biological monitor for OP exposure, the current study characterized salivary ChE activity in Sprague-Dawley rats through its comparison with brain and plasma ChE using BW284C51 and iso-OMPA as selective inhibitors of AChE and BuChE, respectively. The study also estimated the kinetic constants describing BuChE interaction with CPF-oxon. A modified Ellman assay in conjunction with pharmacodynamic (PD) modeling was used to characterize the in vitro titration of diluted rat salivary ChE enzyme with CPF-oxon. The results indicated that, more than 95% of rat salivary ChE activity was associated with BuChE activity, total BuChE active site concentration was 0.0012 0.00013 nmol/ml saliva, reactivation rate constant (Kr) was 0.068 0.008 h-1 and inhibitory (Ki) rate constant of 8.825 and 9.80 nM-1h-1 determined experimentally and using model optimization respectively. These study results would be helpful for further evaluating the potential utility of salivary ChE as a practical tool for biological monitor of OP exposures.« less

Perrhenate complexation by uranyl in traditional solvents and in ionic liquids: a joint molecular dynamics/spectroscopic study.

PubMed

Chaumont, Alain; Klimchuk, Olga; Gaillard, Clotilde; Billard, Isabelle; Ouadi, Ali; Hennig, Christoph; Wipff, Georges

2012-03-15

The complexation of perrhenate (ReO(4)(-)) anions by the uranyl (UO(2)(2+)) cation has been investigated by joint molecular dynamics simulations and spectroscopic (UV-vis, TRLFS, and EXAFS) studies in aqueous solution, acetonitrile, and three ionic liquids (ILs), namely, [Bmi][Tf(2)N], [Me(3)BuN][Tf(2)N], and [Bu(3)MeN][Tf(2)N] that are based on the same Tf(2)N(-) anion (bis(trifluoromethylsulfonyl)imide) and either Bmi(+) (1-butyl,3-methylimidazolium), Me(3)BuN(+), or Bu(3)MeN(+) cations. They show that ReO(4)(-) behaves as a weak ligand in aqueous solution and as a strong ligand in acetonitrile and in the ILs. According to MD simulations in aqueous solution, the UO(2)(ReO(4))(2) complex quickly dissociates to form UO(2)(H(2)O)(5)(2+), while in acetonitrile, a stable UO(2)(ReO(4))(5)(3-) species forms from dissociated ions. In the ILs, the UO(2)(ReO(4))(n)(2-n) complexes (n = 1 to 5) remained stable along the dynamics, and to assess their relative stabilities, we computed the free energy profiles for stepwise ReO(4)(-) complexation to uranyl. In the two studied ILs, complexation is favored, leading to the UO(2)(ReO(4))(5)(3-) species in [Bmi][Tf(2)N] and to UO(2)(ReO(4))(4)(2-) in [Bu(3)MeN][Tf(2)N]. Furthermore, in both acetonitrile and [Bmi][Tf(2)N] solutions, MD and PMF simulations support the formation of dimeric uranyl complexes [UO(2)(ReO(4))(4)](2)(4-) with two bridging ReO(4)(-) ligands. The simulation results are qualitatively consistent with spectroscopic observations in the different solvents, without firmly concluding, however, on the precise composition and structure of the complexes in the solutions. © 2012 American Chemical Society

Synthesis of t-Butyl (2R)-Hydroxyisovalerate, A Precursor of Aureobasidin B

NASA Astrophysics Data System (ADS)

Maharani, R.; Puspitasari, D.; Taufiqqurahman; Huspa, D. H. P.; Hidayat, A. T.; Sumiarsa, D.; Hidayat, I. W.

2017-02-01

Aureobasidins are a family of cyclodepsipeptides have antifungal properties. They were isolated from the black yeast Aureobasidium pullulans R106 and over 30 derivatives have been successfully characterized. There are few publications reporting the total synthesis of aureobasidins. The limited reports of the synthesis of the aureobasidin derivatives are due to the difficult access to the preparations of precursors. The aim of this research is to synthesise a precursor of aureobasidin B, t-butyl (2R)-hydroxyisovalerate (t-Bu-Hiv), that is prepared for the total synthesis of aureobasidin B. The synthesis of AbB is planned to be undertaken by using a solid phase method, so the ester formation between t-Bu-Hiv and the Fmoc-β-hydroxymethylvaline will be carried out in solution phase to form depsidipeptide. The t-butyl group was used as protecting agent that is due to the straightforward elimination of the protecting group from the Fmoc-depsidipeptide. The t-Bu-Hiv acid was prepared from D-valine through diazotisation to form (2R)-acetyloxyisovaleric acid in 62.7% yield. Product of the first step was then protected by t-butyl group by using Boc-anhydride in t-butanol to give t-butil (2R)-acetyloxyisovalerate in 44% yield. In the last step, the acetyloxy group was eliminated by using potassium carbonate in methanol/water to give the desired product, t-Bu-Hiv in 33.5% yield. The t-Bu-Hiv is ready to be combined with Fmoc-β-hydroxymethylvaline to result in depsidipeptide that will be attached to the resin in the total synthesis of AbB. Each stage of this synthesis was controlled by thin layer chromatography and all products were purified by open column chromatography. All the synthesized products were characterized by various spectroscopic techniques, including infrared spectrophotometer, mass spectroscopy (ESI-MS), 1H-NMR and 13C-NMR.

Synthesis and molecular structure of a spheroidal binary nanoscale copper sulfide cluster.

PubMed

Bestgen, Sebastian; Fuhr, Olaf; Roesky, Peter W; Fenske, Dieter

2016-09-27

The reaction of copper(4-(tert-butyl)phenyl)methanethiolate [CuSCH 2 C 6 H 4 t Bu] with bis(trimethylsilyl)sulfide S(SiMe 3 ) 2 in the presence of triphenylphosphine PPh 3 afforded the binary 52 nuclear copper cluster [Cu 52 S 12 (SCH 2 C 6 H 4 t Bu) 28 (PPh 3 ) 8 ]. The molecular structure of this intensely red coloured nanoscale Cu 2 S mimic was established by single crystal X-ray diffraction.

Metal-organic chemical vapour deposition of polycrystalline tetragonal indium sulphide (InS) thin films

NASA Technical Reports Server (NTRS)

Macinnes, Andrew N.; Cleaver, William M.; Barron, Andrew R.; Power, Michael B.; Hepp, Aloysius F.

1992-01-01

The dimeric indium thiolate /(t Bu)2In(mu-S sup t Bu)/2 has been used as a single-source precursor for the MOCVD of InS thin films. The dimeric In2S2 core is proposed to account for the formation of the nonequilibrium high-pressure tetragonal phase in the deposited films. Analysis of the deposited films has been obtained by TEM, with associated energy-dispersive X-ray analysis and X-ray photoelectron spectroscopy.

Lithium-promoted hydrogenation of carbon dioxide to formates by heterobimetallic hydridozinc alkoxide clusters.

PubMed

Merz, Klaus; Moreno, Mariluna; Löffler, Elke; Khodeir, Lamy; Rittermeier, Andre; Fink, Karin; Kotsis, Konstantinos; Muhler, Martin; Driess, Matthias

2008-01-07

The remarkably distinct reactivity of hydridozinc heterobimetallic cubanes [(HZnOtBu)4-n(thf LiOtBu)n] 1a-1d towards CO2 is reported--the hydride transfer from Zn-H to CO2 is drastically accelerated in the presence of Li ions in 1b-1d which led to the respective metal formate hydrates; the systems are inspiring models for the selective conversion of water gas into formates on lithium-promoted ZnO supports.

Luminescence Probe Studies of Ionomers. I. Steady-State Measurements from Nafion Membrane.

DTIC Science & Technology

1985-02-03

Bu4N+ was monitored by titrating the released protons with NaOH. Bu4N+ uptake by Na+ membranes was assumed to be the same as uptake by acidic form...spaced excited states (21). Because of their solvent sensitivity, 1,5-DNS derivatives may also be used as polarity probes (20). The acid -base... acid . The basic (unprotonated) form of the DNS derivative used here (DA+ ) shows *absorption maxima at ca. 325 and 245 nm (aqueous solution, pH 6.8

Quantification of regenerative potential in primary human mammary epithelial cells

PubMed Central

Linnemann, Jelena R.; Miura, Haruko; Meixner, Lisa K.; Irmler, Martin; Kloos, Uwe J.; Hirschi, Benjamin; Bartsch, Harald S.; Sass, Steffen; Beckers, Johannes; Theis, Fabian J.; Gabka, Christian; Sotlar, Karl; Scheel, Christina H.

2015-01-01

We present an organoid regeneration assay in which freshly isolated human mammary epithelial cells are cultured in adherent or floating collagen gels, corresponding to a rigid or compliant matrix environment. In both conditions, luminal progenitors form spheres, whereas basal cells generate branched ductal structures. In compliant but not rigid collagen gels, branching ducts form alveoli at their tips, express basal and luminal markers at correct positions, and display contractility, which is required for alveologenesis. Thereby, branched structures generated in compliant collagen gels resemble terminal ductal-lobular units (TDLUs), the functional units of the mammary gland. Using the membrane metallo-endopeptidase CD10 as a surface marker enriches for TDLU formation and reveals the presence of stromal cells within the CD49fhi/EpCAM− population. In summary, we describe a defined in vitro assay system to quantify cells with regenerative potential and systematically investigate their interaction with the physical environment at distinct steps of morphogenesis. PMID:26071498

Increased plasma pancreatic polypeptide in chronic alcohol abuse.

PubMed

Fink, R S; Adrian, T E; Margot, D H; Bloom, S R

1983-04-01

Post-prandial plasma gastrointestinal hormone profiles were measured in nine chronic alcoholics, one and fourteen days after complete alcohol withdrawal. Basal plasma pancreatic polypeptide concentration (PP--mean +/- SE mean) was significantly greater in alcoholics (control, 28 +/- 5 pmol/l; alcoholics, post-withdrawal day 1, 62 +/- 14 pmol/l, P less than 0.05; and post-withdrawal day 14, 89 +/- 17 pmol/1, P less than 0.005). The total integrated (TIR) PP response following a test breakfast was similarly elevated (control, 442 +/- 63 units; alcoholics, day 1, 1310 +/- 231 units, P less than 0.005; day 14,1066 +/- 66, P less than 0.005). Basal and TIR values for gastrin, gastric inhibitory peptide, insulin and glucagon were similar in alcoholics and controls. As PP has been shown to inhibit pancreatic exocrine enzyme secretion, these findings may help explain the abnormal pancreatic function seen frequently in alcoholics.

The Lack of a Long-Term Growth Effect of Annosus Control in Southeastern United States

Treesearch

F. H. Tainter; J. G. Williams; N. J. Hess; S. W. Oak; D. A. Starkey

1989-01-01

An evaluation of basal area increment was made in 1988 of six pine plantations located across the southeastern United States. These plantations had been thinned in 1969-1970 and stumps treated with borax to measure long-term efficacy of annosus root rot control. In the present study, no long-term growth effects were identified. There were neither negative growth...

Stockability: A major factor in productivity differences between Pinus taeda plantations in Hawaii and the Southeastern United States.

Treesearch

Dean S. DeBell; William R. Harms; Craig D. Whitesell

1989-01-01

Basal area and volume production in loblolly pine spacing trials in Hawaii were nearly double the average production in research plantings in the Southeastern United States. The higher productivity in Hawaii was associated, to some extent, with site index and more rapid growth of individual trees. Competition-related mortality, however, was considerably lower in Hawaii...

Largest-Crown- Width Prediction Models for 53 Species in the Western United States

Treesearch

William A. Bechtold

2004-01-01

The mean crown diameters of stand-grown trees 5.0-in. dbh and larger were modeled as a function of stem diameter, live-crown ratio, stand-level basal area, latitude, longitude, elevation, and Hopkins bioclimatic index for 53 tree species in the western United States. Stem diameter was statistically significant in all models, and a quadratic term for stem diameter was...

Crown-Diameter Prediction Models for 87 Species of Stand-Grown Trees in the Eastern United States

Treesearch

William A. Bechtold

2003-01-01

The mean crown diameters of stand-grown trees were modeled as a function of stem diameter, live-crown ratio, stand basal area, latitude, longitude, elevation, and Hopkins bioclimatic index for 87 tree species in the eastern United States. Stem diameter was statistically significant in all models, and a quadratic term for stem diameter was required for some species....

Subsurface structure of Planum Boreum from Mars Reconnaissance Orbiter Shallow Radar soundings

NASA Astrophysics Data System (ADS)

Putzig, Nathaniel E.; Phillips, Roger J.; Campbell, Bruce A.; Holt, John W.; Plaut, Jeffrey J.; Carter, Lynn M.; Egan, Anthony F.; Bernardini, Fabrizio; Safaeinili, Ali; Seu, Roberto

2009-12-01

We map the subsurface structure of Planum Boreum using sounding data from the Shallow Radar (SHARAD) instrument onboard the Mars Reconnaissance Orbiter. Radar coverage throughout the 1,000,000-km 2 area reveals widespread reflections from basal and internal interfaces of the north polar layered deposits (NPLD). A dome-shaped zone of diffuse reflectivity up to 12 μs (˜1-km thick) underlies two-thirds of the NPLD, predominantly in the main lobe but also extending into the Gemina Lingula lobe across Chasma Boreale. We equate this zone with a basal unit identified in image data as Amazonian sand-rich layered deposits [Byrne, S., Murray, B.C., 2002. J. Geophys. Res. 107, 5044, 12 pp. doi:10.1029/2001JE001615; Fishbaugh, K.E., Head, J.W., 2005. Icarus 174, 444-474; Tanaka, K.L., Rodriguez, J.A.P., Skinner, J.A., Bourke, M.C., Fortezzo, C.M., Herkenhoff, K.E., Kolb, E.J., Okubo, C.H., 2008. Icarus 196, 318-358]. Elsewhere, the NPLD base is remarkably flat-lying and co-planar with the exposed surface of the surrounding Vastitas Borealis materials. Within the NPLD, we delineate and map four units based on the radar-layer packets of Phillips et al. [Phillips, R.J., and 26 colleagues, 2008. Science 320, 1182-1185] that extend throughout the deposits and a fifth unit confined to eastern Gemina Lingula. We estimate the volume of each internal unit and of the entire NPLD stack (821,000 km 3), exclusive of the basal unit. Correlation of these units to models of insolation cycles and polar deposition [Laskar, J., Levrard, B., Mustard, J.F., 2002. Nature 419, 375-377; Levrard, B., Forget, F., Montmessin, F., Laskar, J., 2007. J. Geophys. Res. 112, E06012, 18 pp. doi:10.1029/2006JE002772] is consistent with the 4.2-Ma age of the oldest preserved NPLD obtained by Levrard et al. [Levrard, B., Forget, F., Montmessin, F., Laskar, J., 2007. J. Geophys. Res. 112, E06012, 18 pp. doi:10.1029/2006JE002772]. We suggest a dominant layering mechanism of dust-content variation during accumulation rather than one of lag production during periods of sublimation.

Monomeric and oligomeric amine-borane sigma-complexes of rhodium. intermediates in the catalytic dehydrogenation of amine-boranes.

PubMed

Douglas, Thomas M; Chaplin, Adrian B; Weller, Andrew S; Yang, Xinzheng; Hall, Michael B

2009-10-28

A combined experimental/quantum chemical investigation of the transition metal-mediated dehydrocoupling reaction of H(3)B.NMe(2)H to ultimately give the cyclic dimer [H(2)BNMe(2)](2) is reported. Intermediates and model complexes have been isolated, including examples of amine-borane sigma-complexes of Rh(I) and Rh(III). These come from addition of a suitable amine-borane to the crystallographically characterized precursor [Rh(eta(6)-1,2-F(2)C(6)H(4))(P(i)Bu(3))(2)][BAr(F)(4)] [Ar(F) = 3,5-(CF(3))(2)C(6)H(3)]. The complexes [Rh(eta(2)-H(3)B.NMe(3))(P(i)Bu(3))(2)][BAr(F)(4)] and [Rh(H)(2)(eta(2)-H(3)B.NHMe(2))(P(i)Bu(3))(2)][BAr(F)(4)] have also been crystallographically characterized. Other intermediates that stem from either H(2) loss or gain have been characterized in solution by NMR spectroscopy and ESI-MS. These complexes are competent in the catalytic dehydrocoupling (5 mol %) of H(3)B.NMe(2)H. During catalysis the linear dimer amine-borane H(3)B.NMe(2)BH(2).NHMe(2) is observed which follows a characteristic intermediate time/concentration profile. The corresponding amine-borane sigma-complex, [Rh(P(i)Bu(3))(2)(eta(2)-H(3)B.NMe(2)BH(2).NHMe(2))][BAr(F)(4)], has been isolated and crystallographically characterized. A Rh(I) complex of the final product, [Rh(P(i)Bu(3))(2){eta(2)-(H(2)BNMe(2))(2)}][BAr(F)(4)], is also reported, although this complex lies outside the proposed catalytic cycle. DFT calculations show that the first proposed dehydrogenation step, to give H(2)B horizontal lineNMe(2), proceeds via two possible routes of essentially the same energy barrier: BH or NH activation followed by NH or BH activation, respectively. Subsequent to this, two possible low energy routes that invoke either H(2)/H(2)B horizontal lineNMe(2) loss or H(2)B horizontal lineNMe(2)/H(2) loss are suggested. For the second dehydrogenation step, which ultimately affords [H(2)BNMe(2)](2), a number of experimental observations suggest that a simple intramolecular route is not operating: (i) the isolated complex [Rh(P(i)Bu(3))(2)(eta(2)-H(3)B.NMe(2)BH(2).NHMe(2))][BAr(F)(4)] is stable in the absence of amine-boranes; (ii) addition of H(3)B.NMe(2)BH(2).NHMe(2) to [Rh(P(i)Bu(3))(2)(eta(2)-H(3)B.NMe(2)BH(2).NHMe(2))][BAr(F)(4)] initiates dehydrocoupling; and (iii) H(2)B horizontal lineNMe(2) is also observed during this process.

Nanostructured films employed as sensing units in an "electronic tongue" system.

PubMed

da Silva, B A; Antunes, P A; Pasquini, D; Curvelo, A A S; Aroca, R F; Riul, A Júnior; Constantino, C J L

2007-02-01

Nanostructured films of lignin (macromolecule extracted from sugar cane bagasse), polypyrrole (conducting polymer) and bis butylimido perylene (organic dye) were used in the detection of trace levels of fluorine (from H2SiF6), chlorine (from NaClO), Pb(+2), Cu(+2), and Cd(+2) in aqueous solutions. Langmuir monolayers on ultrapure water were characterised by surface pressure-mean molecular area (II-A) isotherms. Langmuir-Blodgett (LB) films were transferred onto gold interdigitated electrodes and used as individual sensing units of an electronic tongue system. Impedance spectroscopy measurements were taken with the sensor immersed into aqueous solutions containing the ions described above in different molar concentrations. Fourier transform infrared absorption (FTIR) was employed to identify possible interactions between the LB films and the analytes in solution, and no significant changes could be observed in the FTIR spectra of BuPTCD and Ppy. Therefore, the results for lignin point to an interaction involving the electronic cloud of the phenyl groups with the metallic ions.

Description of Arundel Clay ornithomimosaur material and a reinterpretation of Nedcolbertia justinhofmanni as an "Ostrich Dinosaur": biogeographic implications.

PubMed

Brownstein, Chase Doran

2017-01-01

The fossil record of dinosaurs from the Early Cretaceous of Eastern North America is scant, especially since a few stratigraphic units from the east are fossiliferous. Among these stratigraphic units, the Arundel Clay of the eastern seaboard has produced the best-characterized dinosaur faunas known from the Early Cretaceous of Eastern North America. The diverse dinosaur fauna of the Arundel Clay has been thoroughly discussed previously, but a few of the dinosaur species originally described from the Arundel Clay are still regarded as valid genera. Much of the Arundel material is in need of review and redescription. Among the fossils of dinosaurs from this stratigraphic unit are those referred to ornithomimosaurs. Here, the researcher describes ornithomimosaur remains from the Arundel Clay of Prince George's County, Maryland which may be from two distinct ornithomimosaur taxa. These remains provide key information on the theropods of the Early Cretaceous of Eastern North America. Recent discoveries of small theropod material from the Arundel Clay possibly belonging to ornithomimosaurs are also reviewed and described for the first time. The description of the Arundel material herein along with recent discoveries of basal ornithomimosaurs in the past 15 years has allowed for comparisons with the coelurosaur Nedcolbertia justinhofmanni , suggesting the latter animal was a basal ornithomimosaur rather than a "generalized" coelurosaur as it was originally described. Comparisons between the Arundel ornithomimosaur material and similar Asian and European specimens suggest that both extremely basal ornithomimosaurs and more intermediate or derived forms may have coexisted throughout the northern hemisphere during the Early Cretaceous.

Consequences of partial and severe dopaminergic lesion on basal ganglia oscillatory activity and akinesia.

PubMed

Tseng, Kuei Y; Kargieman, Lucila; Gacio, Sebastian; Riquelme, Luis A; Murer, M Gustavo

2005-11-01

Severe chronic dopamine (DA) depletion increases the proportion of neurons in the basal ganglia that fire rhythmic bursts of action potential (LFO units) synchronously with the cortical oscillations. Here we report on how different levels of mesencephalic DA denervation affect substantia nigra pars reticulata (SNpr) neuronal activity in the rat and its relationship to akinesia (stepping test). Chronic nigrostriatal lesion induced with 0 (control group), 4, 6 or 8 microg of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle resulted in a dose-dependent decrease of tyrosine hydroxylase positive (TH+) neurons in the SN and ventral tegmental area (VTA). Although 4 microg of 6-OHDA reduced the number of TH+ neurons in the SN by approximately 60%, both stepping test performance and SNpr neuronal activity remained indistinguishable from control animals. By contrast, animals that received 6 microg of 6-OHDA showed a marked reduction of TH+ cells in the SN ( approximately 75%) and VTA ( approximately 55%), a significant stepping test deficit and an increased proportion of LFO units. These changes were not dramatically enhanced with 8 microg 6-OHDA, a dose that induced an extensive DA lesion (> 95%) in the SN and approximately 70% reduction of DA neurons in the VTA. These results suggest a threshold level of DA denervation for both the appearance of motor deficits and LFO units. Thus, the presence of LFO activity in the SNpr is not related to a complete nigrostriatal DA neuron depletion (ultimate stage parkinsonism); instead, it may reflect a functional disruption of cortico-basal ganglia dynamics associated with clinically relevant stages of the disease.

An Investigation of a Design for a Finite-Difference Time Domain (FDTD) Hardware Accelerator

DTIC Science & Technology

1991-12-01

D PTR), accumulators A and B ( ACCA & ACCB), and the third fixed incrementer (IN3). The stack file in the floating-point unit is untouched. The first...of data. REGISTERS: R1, R2, R4, R5, R7, R8, R9, R11, R12, R13, ACCA , ACCB, MBR. MAR, STAT POINTERS: APT, BPT, CPT, DPT, AIN, BIN, CIN, DIN, IN3 LINES...BBUS MARh-2 READ BACTL, 12 R2 =En(lj) R2=D MAR+2 READ BAACT; 13 MBR = En+I(1j) ACCA = En(0,j-1) + En(lj-1) BU=R2 BL=R2 CD C=R1 MBR=D FP++ a=CBUS b=BBUS

Radical anionic versus neutral 2,2'-bipyridyl coordination in uranium complexes supported by amide and ketimide ligands.

PubMed

Diaconescu, Paula L; Cummins, Christopher C

2015-02-14

The synthesis and characterization of (bipy)(2)U(N[t-Bu]Ar)(2) (1-(bipy)(2), bipy = 2,2'-bipyridyl, Ar = 3,5-C(6)H(3)Me(2)), (bipy)U(N[(1)Ad]Ar)(3) (2-bipy), (bipy)(2)U(NC[t-Bu]Mes)(3) (3-(bipy)(2), Mes = 2,4,6-C(6)H(2)Me(3)), and IU(bipy)(NC[t-Bu]Mes)(3) (3-I-bipy) are reported. X-ray crystallography studies indicate that bipy coordinates as a radical anion in 1-(bipy)(2) and 2-bipy, and as a neutral ligand in 3-I-bipy. In 3-(bipy)(2), one of the bipy ligands is best viewed as a radical anion, the other as a neutral ligand. The electronic structure assignments are supported by NMR spectroscopy studies of exchange experiments with 4,4'-dimethyl-2,2'-bipyridyl and also by optical spectroscopy. In all complexes, uranium was assigned a +4 formal oxidation state.

Multicenter External Quality Assessment Program for PCR Detection of Mycobacterium ulcerans in Clinical and Environmental Specimens

PubMed Central

Eddyani, Miriam; Lavender, Caroline; de Rijk, Willem Bram; Bomans, Pieter; Fyfe, Janet; de Jong, Bouke; Portaels, Françoise

2014-01-01

Background Mycobacterium ulcerans is the causative agent of Buruli ulcer (BU), a necrotizing disease of the skin, soft tissue and bone. PCR is increasingly used in the diagnosis of BU and in research on the mode of transmission and environmental reservoir of M. ulcerans. Methodology/Principal Findings The aim of this study was to evaluate the performance of laboratories in detecting M. ulcerans using molecular tests in clinical and environmental samples by implementing sequential multicenter external quality assessment (EQA) programs. The second round of the clinical EQA program revealed somewhat improved performance. Conclusions/Significance Ongoing EQA programs remain essential and continued participation in future EQA programs by laboratories involved in the molecular testing of clinical and environmental samples for M. ulcerans for diagnostic and research purposes is strongly encouraged. Broad participation in such EQA programs also benefits the harmonization of quality in the BU research community and enhances the credibility of advances made in solving the transmission enigma of M. ulcerans. PMID:24586755

Pseudomonas aeruginosa cytochrome c551 denaturation by five systematic urea derivatives that differ in the alkyl chain length.

PubMed

Kobayashi, Shinya; Fujii, Sotaro; Koga, Aya; Wakai, Satoshi; Matubayasi, Nobuyuki; Sambongi, Yoshihiro

2017-07-01

Reversible denaturation of Pseudomonas aeruginosa cytochrome c 551 (PAc 551 ) could be followed using five systematic urea derivatives that differ in the alkyl chain length, i.e. urea, N-methylurea (MU), N-ethylurea (EU), N-propylurea (PU), and N-butylurea (BU). The BU concentration was the lowest required for the PAc 551 denaturation, those of PU, EU, MU, and urea being gradually higher. Furthermore, the accessible surface area difference upon PAc 551 denaturation caused by BU was found to be the highest, those by PU, EU, MU, and urea being gradually lower. These findings indicate that urea derivatives with longer alkyl chains are stronger denaturants. In this study, as many as five systematic urea derivatives could be applied for the reversible denaturation of a single protein, PAc 551 , for the first time, and the effects of the alkyl chain length on protein denaturation were systematically verified by means of thermodynamic parameters.

Analysis of flavonoid glycosides with potential medicinal properties on Bauhinia uruguayensis and Bauhinia forficata subspecies pruinosa.

PubMed

Santos, Marina; Fortunato, Renée H; Spotorno, Viviana G

2018-04-05

Several Bauhinia species are widely used in Southern South America in the treatment of infections, pain and several diseases including diabetes. Flavonoid compounds based on quercetin and kaempferol glycoside derivatives are believed to be responsible for their therapeutic properties. To investigate this, we have studied two native species from Argentina: B. uruguayensis (BU) and B. forficata subsp. pruinosa (BF). We have analyzed the major polyphenol components in hydro-methanolic extracts of leaves, by high performance liquid chromatography tandem mass spectrometry. Chromatographic analysis yielded five main compounds in BF, corresponding to rutinosides and rhamnosides derivatives of kaempferol and quercetin, which are considered chemotaxonomic markers and responsible for antioxidant activity. The presence of kaempferitrin, an antidiabetic agent, has been confirmed. In extracts of BU, four major compounds were identified as rhamnosides and galloyl derivates from quercetin and kaempferol. One of these compounds, quercitrin-3-rhamnoside may confer anti-inflammatory and analgesic properties to BU extracts.

Extractant composition including crown ether and calixarene extractants

DOEpatents

Meikrantz, David H.; Todd, Terry A.; Riddle, Catherine L.; Law, Jack D.; Peterman, Dean R.; Mincher, Bruce J.; McGrath, Christopher A.; Baker, John D.

2009-04-28

An extractant composition comprising a mixed extractant solvent consisting of calix[4] arene-bis-(tert-octylbenzo)-crown-6 ("BOBCalixC6"), 4',4',(5')-di-(t-butyldicyclo-hexano)-18-crown-6 ("DtBu18C6"), and at least one modifier dissolved in a diluent. The DtBu18C6 may be present at from approximately 0.01M to approximately 0.4M, such as at from approximately 0.086 M to approximately 0.108 M. The modifier may be 1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol ("Cs-7SB") and may be present at from approximately 0.01M to approximately 0.8M. In one embodiment, the mixed extractant solvent includes approximately 0.15M DtBu18C6, approximately 0.007M BOBCalixC6, and approximately 0.75M Cs-7SB modifier dissolved in an isoparaffinic hydrocarbon diluent. The extractant composition further comprises an aqueous phase. The mixed extractant solvent may be used to remove cesium and strontium from the aqueous phase.

Molecular Characterization of Staphylococcus aureus Isolates Transmitted between Patients with Buruli Ulcer

PubMed Central

Amissah, Nana Ama; Chlebowicz, Monika A.; Ablordey, Anthony; Sabat, Artur J.; Tetteh, Caitlin S.; Prah, Isaac; van der Werf, Tjip S.; Friedrich, Alex W.; van Dijl, Jan Maarten

2015-01-01

Background Buruli ulcer (BU) is a skin infection caused by Mycobacterium ulcerans. The wounds of most BU patients are colonized with different microorganisms, including Staphylococcus aureus. Methodology This study investigated possible patient-to-patient transmission events of S. aureus during wound care in a health care center. S. aureus isolates from different BU patients with overlapping visits to the clinic were whole-genome sequenced and analyzed by a gene-by-gene approach using SeqSphere+ software. In addition, sequence data were screened for the presence of genes that conferred antibiotic resistance. Principal Findings SeqSphere+ analysis of whole-genome sequence data confirmed transmission of methicillin resistant S. aureus (MRSA) and methicillin susceptible S. aureus among patients that took place during wound care. Interestingly, our sequence data show that the investigated MRSA isolates carry a novel allele of the fexB gene conferring chloramphenicol resistance, which had thus far not been observed in S. aureus. PMID:26360794

Evidence for the presence of a mammalian-like cholinesterase in Paramecium primaurelia (Protista, Ciliophora) developmental cycle.

PubMed

Delmonte Corrado, M U; Politi, H; Trielli, F; Angelini, C; Falugi, C

1999-01-01

By histochemical and immunohistochemical methods, the presence of cholinergic-like molecules has previously been demonstrated in Paramecium primaurelia, and their functional role in mating-cell pairing was suggested. In this work, both true acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activities were electrophoretically investigated, and the presence of molecules immunologically related to BuChE was checked by immunoblotting. The AChE activity, shown in the membrane protein fraction of mating-competent cells and in the cytoplasmic fraction of immature cells, is due to a 260-kDa molecular form, similar to the membrane-bound tetrameric form present in human erythrocytes. This AChE activity does not appear in either the cytoplasmic fraction of mating-competent cells or in the membrane protein fraction of immature cells. No evidence was found for the presence or the activity of BuChE-like molecules. The role of AChE in P. primaurelia developmental cycle is discussed.

Situated knowledge of pathogenic landscapes in Ghana: Understanding the emergence of Buruli ulcer through qualitative analysis.

PubMed

Tschakert, Petra; Ricciardi, Vincent; Smithwick, Erica; Machado, Mario; Ferring, David; Hausermann, Heidi; Bug, Leah

2016-02-01

Successfully addressing neglected tropical diseases requires nuanced understandings of pathogenic landscapes that incorporate situated, contexualized community knowledge. In the case of Buruli ulcer (BU), the role of social science is vital to investigate complex human-environment interactions and navigate different ways of knowing. We analyze a set of qualitative data from our interdisciplinary project on BU in Ghana, drawing from participatory mapping, focus group discussions, semi-structured interviews, and open-ended survey questions to explore how people in endemic and non-endemic areas see themselves embedded in changing environmental and social landscapes. We pay particular attention to landscape disturbance through logging and small-scale alluvial gold mining. The results from our participatory research underscore the holistic nature of BU emergence in landscapes, encapsulated in partial and incomplete local descriptions, the relevance of collective learning to distill complexity, and the potential of rich qualitative data to inform quantitative landscape-disease models. Copyright © 2015 Elsevier Ltd. All rights reserved.

Crystal structure and electronic properties of a thiolate-protected Au24 nanocluster

NASA Astrophysics Data System (ADS)

Das, Anindita; Li, Tao; Li, Gao; Nobusada, Katsuyuki; Zeng, Chenjie; Rosi, Nathaniel L.; Jin, Rongchao

2014-05-01

Solving the total structures of gold nanoclusters is of critical importance for understanding their electronic, optical and catalytic properties. Herein, we report the X-ray structure of a charge-neutral Au24(SCH2Ph-tBu)20 nanocluster. This structure features a bi-tetrahedral Au8 kernel protected by four tetrameric staple-like motifs. Electronic structure analysis is further carried out and the optical absorption spectrum is interpreted. The Au24(SCH2Ph-tBu)20, Au23(S-c-C6H11)16 and Au25(SCH2CH2Ph)18 nanoclusters constitute the first crystallographically characterized ``trio''.Solving the total structures of gold nanoclusters is of critical importance for understanding their electronic, optical and catalytic properties. Herein, we report the X-ray structure of a charge-neutral Au24(SCH2Ph-tBu)20 nanocluster. This structure features a bi-tetrahedral Au8 kernel protected by four tetrameric staple-like motifs. Electronic structure analysis is further carried out and the optical absorption spectrum is interpreted. The Au24(SCH2Ph-tBu)20, Au23(S-c-C6H11)16 and Au25(SCH2CH2Ph)18 nanoclusters constitute the first crystallographically characterized ``trio''. Electronic supplementary information (ESI) available: Experimental and supporting Fig. S1-S3. CCDC NUMBER(1000102). For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c4nr01350f

Functional Characterization of a Strong Bi-directional Constitutive Plant Promoter Isolated from Cotton Leaf Curl Burewala Virus

PubMed Central

Khan, Zainul A.; Abdin, Malik Z.; Khan, Jawaid A.

2015-01-01

Cotton leaf curl Burewala virus (CLCuBuV), belonging to the genus Begomovirus, possesses single-stranded monopartite DNA genome. The bidirectional promoters representing Rep and coat protein (CP) genes of CLCuBuV were characterized and their efficacy was assayed. Rep and CP promoters of CLCuBuV and 35S promoter of Cauliflower mosaic virus (CaMV) were fused with β-glucuronidase (GUS) and green fluorescent protein (GFP) reporter genes. GUS activity in individual plant cells driven by Rep, CP and 35S promoters was estimated using real-time PCR and fluorometric GUS assay. Histochemical staining of GUS in transformed tobacco (Nicotiana tabacum cv. Xanthi) leaves showed highest expression driven by Rep promoter followed by 35S promoter and CP promoter. The expression level of GUS driven by Rep promoter in transformed tobacco plants was shown to be two to four-fold higher than that of 35S promoter, while the expression by CP promoter was slightly lower. Further, the expression of GFP was monitored in agroinfiltrated leaves of N. benthamiana, N. tabacum and cotton (Gossypium hirsutum) plants using confocal laser scanning microscopy. Rep promoter showed strong consistent transient expression in tobacco and cotton leaves as compared to 35S promoter. The strong constitutive CLCuBuV Rep promoter developed in this study could be very useful for high level expression of transgenes in a wide variety of plant cells. PMID:25799504

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stella, Stefano; University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen; Molina, Rafael

Crystal structures of BurrH and the BurrH–DNA complex are reported. DNA editing offers new possibilities in synthetic biology and biomedicine for modulation or modification of cellular functions to organisms. However, inaccuracy in this process may lead to genome damage. To address this important problem, a strategy allowing specific gene modification has been achieved through the addition, removal or exchange of DNA sequences using customized proteins and the endogenous DNA-repair machinery. Therefore, the engineering of specific protein–DNA interactions in protein scaffolds is key to providing ‘toolkits’ for precise genome modification or regulation of gene expression. In a search for putative DNA-bindingmore » domains, BurrH, a protein that recognizes a 19 bp DNA target, was identified. Here, its apo and DNA-bound crystal structures are reported, revealing a central region containing 19 repeats of a helix–loop–helix modular domain (BurrH domain; BuD), which identifies the DNA target by a single residue-to-nucleotide code, thus facilitating its redesign for gene targeting. New DNA-binding specificities have been engineered in this template, showing that BuD-derived nucleases (BuDNs) induce high levels of gene targeting in a locus of the human haemoglobin β (HBB) gene close to mutations responsible for sickle-cell anaemia. Hence, the unique combination of high efficiency and specificity of the BuD arrays can push forward diverse genome-modification approaches for cell or organism redesign, opening new avenues for gene editing.« less

Functional characterization of a strong bi-directional constitutive plant promoter isolated from cotton leaf curl Burewala virus.

PubMed

Khan, Zainul A; Abdin, Malik Z; Khan, Jawaid A

2015-01-01

Cotton leaf curl Burewala virus (CLCuBuV), belonging to the genus Begomovirus, possesses single-stranded monopartite DNA genome. The bidirectional promoters representing Rep and coat protein (CP) genes of CLCuBuV were characterized and their efficacy was assayed. Rep and CP promoters of CLCuBuV and 35S promoter of Cauliflower mosaic virus (CaMV) were fused with β-glucuronidase (GUS) and green fluorescent protein (GFP) reporter genes. GUS activity in individual plant cells driven by Rep, CP and 35S promoters was estimated using real-time PCR and fluorometric GUS assay. Histochemical staining of GUS in transformed tobacco (Nicotiana tabacum cv. Xanthi) leaves showed highest expression driven by Rep promoter followed by 35S promoter and CP promoter. The expression level of GUS driven by Rep promoter in transformed tobacco plants was shown to be two to four-fold higher than that of 35S promoter, while the expression by CP promoter was slightly lower. Further, the expression of GFP was monitored in agroinfiltrated leaves of N. benthamiana, N. tabacum and cotton (Gossypium hirsutum) plants using confocal laser scanning microscopy. Rep promoter showed strong consistent transient expression in tobacco and cotton leaves as compared to 35S promoter. The strong constitutive CLCuBuV Rep promoter developed in this study could be very useful for high level expression of transgenes in a wide variety of plant cells.

Improvement in Long-Term Memory following Chronic Administration of Eryngium planum Root Extract in Scopolamine Model: Behavioral and Molecular Study

PubMed Central

Ozarowski, Marcin; Thiem, Barbara; Mikolajczak, Przemyslaw L.; Piasecka, Anna; Kachlicki, Piotr; Szulc, Michal; Kaminska, Ewa; Kujawski, Radoslaw; Bartkowiak-Wieczorek, Joanna; Kujawska, Malgorzata; Jodynis-Liebert, Jadwiga; Budzianowski, Jaromir; Kędziora, Izabela; Seremak-Mrozikiewicz, Agnieszka; Czerny, Boguslaw; Bobkiewicz-Kozłowska, Teresa

2015-01-01

Eryngium planum L. (EP) is as a rare medicinal plant with a lot of potentials as pharmaceutical crops. The aim of our study was to assess the effect of subchronic (28-fold) administration of a 70% ethanol extract of EP roots (200 mg/kg, p.o.) on behavioral and cognitive responses in Wistar rats linked with acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), and beta-secretase (BACE-1) mRNA levels and AChE and BuChE activities in the hippocampus and frontal cortex. On the last day of experiment, 30 min after the last dose of EP or Huperzine A (HU), scopolamine (SC) was given at a dose of 0.5 mg/kg b.w. intraperitoneally. The results of a passive avoidance test showed an improvement in long-term memory produced by the EP extract in both scopolamine-induced rats and control group. EP caused an insignificant inhibition of AChE and BuChE activities in the frontal cortex and the hippocampus. EP decreased mRNA AChE, BuChE, and BACE-1 levels, especially in the cortex. Our results suggest that the EP extract led to the improvement of the long-term memory in rats coupled with total saponin content. The mechanism of EP action is probably complicated, since HPLC-MS analysis showed 64 chemical compounds (phenolics, saponins) in the extract of EP roots. PMID:26483842

Comparison of the catalytic activity for the Suzuki-Miyaura reaction of (η(5)-Cp)Pd(IPr)Cl with (η(3)-cinnamyl)Pd(IPr)(Cl) and (η(3)-1-t-Bu-indenyl)Pd(IPr)(Cl).

PubMed

Melvin, Patrick R; Hazari, Nilay; Lant, Hannah M C; Peczak, Ian L; Shah, Hemali P

2015-01-01

Complexes of the type (η(3)-allyl)Pd(L)(Cl) and (η(3)-indenyl)Pd(L)(Cl) are highly active precatalysts for the Suzuki-Miyaura reaction. Even though allyl and indenyl ligands are similar to cyclopentadienyl (Cp) ligands, there have been no detailed comparative studies exploring the activity of precatalysts of the type (η(5)-Cp)Pd(L)(Cl) for Suzuki-Miyaura reactions. Here, we compare the catalytic activity of (η(5)-Cp)Pd(IPr)(Cl) (IPr = 1,3-bis(2,6-diisopropylphenyl)-1,3-dihydro-2H-imidazol-2-ylidene, Cp) with two commercially available catalysts (η(3)-cinnamyl)Pd(IPr)(Cl) (Cin) and (η(3)-1-t-Bu-indenyl)Pd(IPr)(Cl) ( (tBu) Ind). We show that Cp gives slightly better catalytic activity than Cin, but significantly inferior activity than (tBu) Ind. This order of activity is rationalized by comparing the rates at which the precatalysts are activated to the monoligated Pd(0) active species along with the tendency of the starting precatalysts to comproportionate with monoligated Pd(0) to form inactive Pd(I) dimers. As part of this work the Cp supported Pd(I) dimer (μ-Cp)(μ-Cl)Pd2(IPr)2 (Cp (Dim) ) was synthesized and crystallographically characterized. It does not readily disproportionate to form monoligated Pd(0) and consequently Cp (Dim) is a poor catalyst for the Suzuki-Miyaura reaction.

Conformational characterization of peptides rich in the cycloaliphatic C alpha,alpha-disubstituted glycine 1-aminocyclononane-1-carboxylic acid.

PubMed

Gatos, M; Formaggio, F; Crisma, M; Valle, G; Toniolo, C; Bonora, G M; Saviano, M; Iacovino, R; Menchise, V; Galdiero, S; Pedone, C; Benedetti, E

1997-01-01

A series of N- and C-protected, monodispersed homo-oligopeptides (to the pentamer level) from the cycloaliphatic C alpha,alpha-dialkylated glycine 1-aminocyclononane-1-carboxylic acid (Ac9c) and two Ala/Ac9c tripeptides have been synthesized by solution methods and fully characterized. The conformational preferences of all the model peptides were determined in deuterochloroform solution by FT-IR absorption and 1H-NMR. The molecular structures of the amino acid derivatives mCIAc-Ac9c-OH and Z-Ac9c-OtBu, the dipeptide pBrBz-(Ac9c)2-OtBu, the tetrapeptide Z-(Ac9c)4-OtBu, and the pentapeptide Z-(Ac9c)5-OtBu were determined in the crystal state by X-ray diffraction. Based on this information, the average geometry and the preferred conformation for the cyclononyl moiety of the Ac9c residue have been assessed. The backbone conformational data are strongly in favour of the conclusion that the Ac9c residue is a strong beta-turn and helix former. A comparison with the structural propensity of alpha-aminoisobutyric acid, the prototype of C alpha,alpha-dialkylated glycines, and the other extensively investigated members of the family of 1-aminocycloalkane-1-carboxylic acids (Acnc, with n = 3-8) is made and the implications for the use of the Ac9c residue in conformationally constrained analogues of bioactive peptides are briefly examined.

Multipotent cholinesterase/monoamine oxidase inhibitors for the treatment of Alzheimer's disease: design, synthesis, biochemical evaluation, ADMET, molecular modeling, and QSAR analysis of novel donepezil-pyridyl hybrids.

PubMed

Bautista-Aguilera, Oscar M; Esteban, Gerard; Chioua, Mourad; Nikolic, Katarina; Agbaba, Danica; Moraleda, Ignacio; Iriepa, Isabel; Soriano, Elena; Samadi, Abdelouahid; Unzeta, Mercedes; Marco-Contelles, José

2014-01-01

The design, synthesis, and biochemical evaluation of donepezil-pyridyl hybrids (DPHs) as multipotent cholinesterase (ChE) and monoamine oxidase (MAO) inhibitors for the potential treatment of Alzheimer's disease (AD) is reported. The 3D-quantitative structure-activity relationship study was used to define 3D-pharmacophores for inhibition of MAO A/B, acetylcholinesterase (AChE), and butyrylcholinesterase (BuChE) enzymes and to design DPHs as novel multi-target drug candidates with potential impact in the therapy of AD. DPH14 (Electrophorus electricus AChE [EeAChE]: half maximal inhibitory concentration [IC50] =1.1±0.3 nM; equine butyrylcholinesterase [eqBuChE]: IC50 =600±80 nM) was 318-fold more potent for the inhibition of AChE, and 1.3-fold less potent for the inhibition of BuChE than the reference compound ASS234. DPH14 is a potent human recombinant BuChE (hBuChE) inhibitor, in the same range as DPH12 or DPH16, but 13.1-fold less potent than DPH15 for the inhibition of human recombinant AChE (hAChE). Compared with donepezil, DPH14 is almost equipotent for the inhibition of hAChE, and 8.8-fold more potent for hBuChE. Concerning human monoamine oxidase (hMAO) A inhibition, only DPH9 and 5 proved active, compound DPH9 being the most potent (IC50 [MAO A] =5,700±2,100 nM). For hMAO B, only DPHs 13 and 14 were moderate inhibitors, and compound DPH14 was the most potent (IC50 [MAO B] =3,950±940 nM). Molecular modeling of inhibitor DPH14 within EeAChE showed a binding mode with an extended conformation, interacting simultaneously with both catalytic and peripheral sites of EeAChE thanks to a linker of appropriate length. Absortion, distribution, metabolism, excretion and toxicity analysis showed that structures lacking phenyl-substituent show better druglikeness profiles; in particular, DPHs13-15 showed the most suitable absortion, distribution, metabolism, excretion and toxicity properties. Novel donepezil-pyridyl hybrid DPH14 is a potent, moderately selective hAChE and selective irreversible hMAO B inhibitor which might be considered as a promising compound for further development for the treatment of AD.