Investigation of Cyclodextrin-Based Nanosponges for Solubility and Bioavailability Enhancement of Rilpivirine.

PubMed

Rao, Monica R P; Chaudhari, Jagruti; Trotta, Francesco; Caldera, Fabrizio

2018-06-04

Rilpivrine is BCS class II drug used for treatment of HIV infection. The drug has low aqueous solubility (0.0166 mg/ml) and dissolution rate leading to low bioavailability (32%). Aim of this work was to enhance solubility and dissolution of rilpivirine using beta-cyclodextrin-based nanosponges. These nanosponges are biocompatible nanoporous particles having high loading capacity to form supramolecular inclusion and non-inclusion complexes with hydrophilic and lipophilic drugs for solubility enhancement. Beta-cyclodextrin was crosslinked with carbonyl diimidazole and pyromellitic dianhydride to prepare nanosponges. The nanosponges were loaded with rilpivirine by solvent evaporation method. Binary and ternary complexes of drug with β-CD, HP-β-CD, nanosponges, and tocopherol polyethylene glycol succinate were prepared and characterized by phase solubility, saturation solubility in different media, in vitro dissolution, and in vivo pharmacokinetics. Spectral analysis by Fourier transform infrared spectroscopy, powder X-ray diffraction, and differential scanning calorimetry was performed. Results obtained from spectral characterization confirmed inclusion complexation. Phase solubility studies indicated stable complex formation. Saturation solubility was found to be 10-13-folds higher with ternary complexes in distilled water and 12-14-fold higher in 0.1 N HCl. Solubility enhancement was evident in biorelevant media. Molecular modeling studies revealed possible mode of entrapment of rilpivirine within β-CD cavities. A 3-fold increase in dissolution with ternary complexes was observed. Animal studies revealed nearly 2-fold increase in oral bioavailability of rilpivirine. It was inferred that electronic interactions, hydrogen bonding, and van der Waals forces are involved in the supramolecular interactions.

Isotope geochemistry and fluid inclusion study of skarns from Vesuvius

USGS Publications Warehouse

Gilg, H.A.; Lima, A.; Somma, R.; Belkin, H.E.; de Vivo, B.; Ayuso, R.A.

2001-01-01

We present new mineral chemistry, fluid inclusion, stable carbon and oxygen, as well as Pb, Sr, and Nd isotope data of Ca-Mg-silicate-rich ejecta (skarns) and associated cognate and xenolithic nodules from the Mt. Somma-Vesuvius volcanic complex, Italy. The typically zoned skarn ejecta consist mainly of diopsidic and hedenbergitic, sometimes "fassaitic" clinopyroxene, Mg-rich and Ti-poor phlogopite, F-bearing vesuvianite, wollastonite, gehlenite, meionite, forsterite, clinohumite, anorthite and Mg-poor calcite with accessory apatite, spinell, magnetite, perovskite, baddeleyite, and various REE-, U-, Th-, Zr- and Ti-rich minerals. Four major types of fluid inclusions were observed in wollastonite, vesuvianite, gehlenite, clinopyroxene and calcite: a) primary silicate melt inclusions (THOM = 1000-1050??C), b) CO2 ?? H2S-rich fluid inclusions (THOM = 20-31.3??C into the vapor phase), c) multiphase aqueous brine inclusions (THOM = 720-820??C) with mainly sylvite and halite daughter minerals, and d) complex chloride-carbonate-sulfate-fluoride-silicate-bearing saline-melt inclusions (THOM = 870-890??C). The last inclusion type shows evidence for immiscibility between several fluids (silicate melt - aqueous chloride-rich liquid - carbonate/sulfate melt?) during heating and cooling below 870??C. There is no evidence for fluid circulation below 700??C and participation of externally derived meteoric fluids in skarn formation. Skarns have considerably variable 206Pb/204Pb (19.047-19.202), 207Pb/204Pb (15.655-15.670), and 208Pb/204Pb (38.915-39.069) and relatively low 143Nd/144Nd (0.51211-0.51244) ratios. The carbon and oxygen isotope compositions of skarn calcites (??13CV-PDB = -5.4 to -1.1???; ??18OV-SMOW = 11.7 to 16.4???) indicate formation from a 18O- and 13C-enriched fluid. The isotope composition of skarns and the presence of silicate melt inclusion-bearing wollastonite nodules suggests assimilation of carbonate wall rocks by the alkaline magma at moderate depths (< 5 km) and consequent exsolution of CO2-rich vapor and complex saline melts from the contaminated magma that reacted with the carbonate rocks to form skarns.

The interaction of caffeine with substituted cyclodextrins in water

NASA Astrophysics Data System (ADS)

Terekhova, I. V.; Kumeev, R. S.; Al'Per, G. A.

2007-07-01

The interaction of caffeine with hydroxypropyl-and methylcyclodextrins in water was studied by the calorimetry, spectroscopy, and solubility methods at 298.15 K. The interaction of caffeine with these cyclodextrins did not result in the formation of stable inclusion complexes and was mostly accompanied by predominantly endothermic effects of particle dehydration. The introduction of substituents and changes in the size of cyclodextrin molecular cavity did not influence the ability of cyclodextrins to form complexes with caffeine. The conclusion was drawn that substituted cyclodextrins could not be used for increasing the solubility of caffeine in water.

Aniline-containing guests recognized by α,α',δ,δ'-tetramethyl-cucurbit[6]uril host.

PubMed

Lin, Rui-Lian; Fang, Guo-Sheng; Sun, Wen-Qi; Liu, Jing-Xin

2016-12-13

The host-guest complexation of symmetrical α,α',δ,δ'-tetramethyl-cucurbit[6]uril (TMeQ[6]) and cucurbit[7]uril (Q[7]) with a series of aniline-containing guests has been investigated by various experimental techniques including NMR, ITC, and X-ray crystallography. Experimental results indicate that both TMeQ[6] and Q[7] hosts can encapsulate aniline-containing guests to form stable inclusion complexes. However, the oval cavity of TMeQ[6] is more complementary in size and shape to the aromatic ring of the guests than the spherical cavity of Q[7]. Shielding and deshielding effects of the aromatic ring on guests lead to the remarkable chemical shifts of the TMeQ[6] host protons. The rotational restriction of the guests in the oval cavity of TMeQ[6] results in the large negative values of entropy. The X-ray crystal structure of the 1:1 inclusion complex between TMeQ[6] and N,N'-diethyl-benzene-1,4-diamine unambiguously reveals that the aromatic ring of the guest resides in the oval cavity of TMeQ[6].

(13)C and (15)N solid-state NMR studies on albendazole and cyclodextrin albendazole complexes.

PubMed

Ferreira, M João G; García, A; Leonardi, D; Salomon, Claudio J; Lamas, M Celina; Nunes, Teresa G

2015-06-05

(13)C and (15)N solid-state nuclear magnetic resonance (NMR) spectra were recorded from albendazole (ABZ) and from ABZ:β-cyclodextrin, ABZ:methyl-β-cyclodextrin, ABZ:hydroxypropyl-β-cyclodextrin and ABZ:citrate-β-cyclodextrin, which were prepared by the spray-drying technique. ABZ signals were typical of a crystalline solid for the pure drug and of an amorphous compound obtained from ABZ:cyclodextrin samples. Relevant spectral differences were correlated with chemical interaction between ABZ and cyclodextrins. The number and type of complexes revealed a strong dependence on the cyclodextrin group substituent. Solid-state NMR data were consistent with the presence of stable inclusion complexes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Complex Particulate Biomaterials as Immunostimulant-Delivery Platforms

PubMed Central

Mamat, Uwe; Wilke, Kathleen; Villaverde, Antonio; Roher, Nerea

2016-01-01

The control of infectious diseases is a major current challenge in intensive aquaculture. Most commercial vaccines are based on live attenuated or inactivated pathogens that are usually combined with adjuvants, oil emulsions being as the most widely used for vaccination in aquaculture. Although effective, the use of these oil emulsions is plagued with important side effects. Thus, the development of alternative safer and cost-effective immunostimulants and adjuvants is highly desirable. Here we have explored the capacity of inclusion bodies produced in bacteria to immunostimulate and protect fish against bacterial infections. Bacterial inclusion bodies are highly stable, non-toxic protein-based biomaterials produced through fully scalable and low-cost bio-production processes. The present study shows that the composition and structured organization of inclusion body components (protein, lipopolysaccharide, peptidoglycan, DNA and RNA) make these protein biomaterials excellent immunomodulators able to generically protect fish against otherwise lethal bacterial challenges. The results obtained in this work provide evidence that their inherent nature makes bacterial inclusion bodies exceptionally attractive as immunostimulants and this opens the door to the future exploration of this biomaterial as an alternative adjuvant for vaccination purposes in veterinary. PMID:27716780

A Physicochemical and Pharmacological Study of the Newly Synthesized Complex of Albendazole and the Polysaccharide Arabinogalactan from Larch Wood.

PubMed

Chistyachenko, Yulia S; Meteleva, Elizaveta S; Pakharukova, Maria Y; Katokhin, Aleksey V; Khvostov, Mikhail V; Varlamova, Anastasiya I; Glamazdin, Igor I; Khalikov, Salavat S; Polyakov, Nikolay E; Arkhipov, Ivan A; Tolstikova, Tatyana G; Mordvinov, Viatcheslav A; Dushkin, Alexander V; Lyakhov, Nikolay Z

2015-01-01

Inclusion complexes of albendazole (ABZ) with the polysaccharide arabinogalactan from larch wood Larix sibirica and Larix gmelinii were synthesized using a solid-state mechanochemical technology. We investigated physicochemical properties of the synthesized complexes in the solid state and in aqueous solutions as well as their anthelmintic activity against Trichinella spiralis, Hymenolepis nаna, Fasciola hepatica, Opisthorchis felineus, and mixed nematodoses of sheep. Formation of the complexes was demonstrated by means of intrinsic solubility and the NMR relaxation method. The mechanochemically synthesized complexes were more stable in comparison with the complex produced by mixing solutions of the components. The complexes of ABZ showed anthelmintic activity at 10-fold lower doses than did free ABZ. The complexes also showed lower acute toxicity and hepatotoxicity. These results suggest that it is possible to design new drugs on the basis of the ABZ:arabinogalactan complex that are safer and more effective than albendazole.

Plagioclase-Hosted Magnetite Inclusions From the Bushveld Complex

NASA Astrophysics Data System (ADS)

Feinberg, J. M.; Scott, G. R.; Renne, P. R.; Wenk, H.

2004-12-01

Gabbros from the Main Zone of the 2.064 Ga Bushveld Complex have long been known to possess unusually stable magnetizations due to the presence of high coercivity, exsolved magnetite inclusions in plagioclase and clinopyroxene. The paleomagnetic pole for these rocks has been used to anchor apparent polar wander paths for the Kaapval craton during the Early-Mid Proterozoic. To better understand the rock magnetic properties of silicate-hosted magnetite inclusions, oriented paleomagnetic samples of gabbro were collected from quarries near Belfast and Rustenberg, South Africa, sampling the eastern and western limbs of the Complex, respectively. Plagioclase composition at both sites ranges from An55 (rims) to An65 (cores) based on optical and electron microprobe data. Four kinds of inclusions are present within the plagioclase: elongate magnetite needles, nanometer-scale magnetite particles (responsible for the "cloudy" appearance of some crystals), translucent brown hematite/ilmenite platelets, and colorless euhedral inclusions of pyroxene and/or feldspar. Magnetite inclusions are most abundant at the cores of the plagioclase crystals. Orientations of the needles and the platelets are crystallographically controlled by the silicate host. Although the elongation direction of the magnetite inclusions can occur in any of five possible orientations, only two or three of these directions dominates each plagioclase crystal. Alternating field demagnetization of bulk samples (NRM = 1.5 x 101 A m-1) shows univectorial remanence with average median destructive fields (MDF) of 115 mT (Belfast) and 90 mT (Rustenberg). AF demagnetization of single plagioclase crystals (NRM = 100 A m-1) also shows single component remanence with average MDFs >150 mT. The NRM coercivity spectra of single plagioclase crystals are indistinguishable from that of the bulk samples. When normalized to their abundance in bulk samples the magnetite-bearing plagioclase fully accounts for the NRM of Bushveld gabbros at both sites. Close examination of the inclusions' interiors using magnetic force microscopy shows no ulvöspinel exsolution as observed in other silicate exsolved titanomagnetites with comparably high coercivities. Consequently, we interpret the high coercivities of the inclusions to be a product of their small size and extreme shape anisotropy. Single crystals of plagioclase demonstrate a strong anisotropy of IRM acquisition (see Scott, et al. this conference). Additionally, electron backscatter diffraction (EBSD) orientation indexing shows a strongly preferred orientation for plagioclase and pyroxene (with (010)plag and (100)pyr parallel to subhorizontal layering) consistent with gravitational settling within a magma chamber. Thus, there are two anisotropies (silicate preferred orientation and magnetite inclusion remanence) to consider when describing the ancient magnetic field present during the emplacement of the Bushveld.

Early Precambrian crustal evolution of south India

NASA Technical Reports Server (NTRS)

Srinivasan, R.

1986-01-01

The Early Precambrian sequence in Karnataka, South India provides evidences for a distinct trend of evolution which differs from trends exhibited in many other Early Precambrian regions of the world. The supracrustal rock associations preserved in greenstone belts and as inclusions in gneisses and granulites suggest the evolution of the terrain from a stable to a mobile regime. The stable regime is represented by (1) layered ultramafic-mafic complexes, (2) orthoquartzite-basalt-rhyodacite-iron formation, and (30 ortho-quartzite-carbonate-Mn-Fe formation. The mobile regime, which can be shown on sedimentological grounds to have succeeded the stable regime, witnessed the accumulation of a greywacke-pillow basalt-dacite-rhyolite-iron formation association. Detrital sediments of the stable zone accumulated dominantly in fluvial environment and the associated volcanics are ubaerial. The volcanics of the stable regime are tholeiites derived from a zirconium and LREE-enriched sources. The greywackes of the mobile regime are turbidities, and the volcanic rocks possess continental margin (island-arc or back-arc) affinity; they show a LREE depleted to slightly LREE-enriched pattern. The evolution from a stable to a mobile regime is in contrast to the trend seen in most other regions of the world, where an early dominantly volcanic association of a mobile regime gives way upward in the sequence to sediments characteristic of a stable regime.

Functionalization of Lipid-Based Nutrient Supplement with β-Cyclodextrin Inclusions of Oregano Essential Oil.

PubMed

Gaur, Shashank; Lopez, Emely C; Ojha, Ankur; Andrade, Juan E

2018-06-01

Intestinal parasitic infection is one of the main causes of acute undernutrition in children. Oral consumption of oregano essential oil (OEO) can reduce intestinal parasitic infections, however, its addition to therapeutic and supplementary foods is hampered by its undesirable flavor. The objective of this study was to develop a functional lipid-based nutrient supplement (LNS) containing OEO, which is stable, acceptable and provides targeted intestinal delivery of bioactive. β-cyclodextrin (β-CyD) inclusion complexes of OEO (β-CyD-OEO), and carvacrol (β-CyD-CV) (1:1 molar) were prepared using slurry complexation (-20 °C) method and characterized based on encapsulation efficiency, moisture content, morphology, and 2-phase in vitro digestion stability. Carvacrol (CV) content was measured using reverse phase HPLC-UV. LNS containing β-CyD-OEO (27.2 mg encapsulate/20 g LNS) was formulated using Indian staples and ingredients. Discriminatory sensory tests (triangle) were performed with college students (n = 58) and low-income women (n = 25), with young children at home (1 to 6 years), living in Mehsana, India to evaluate differences between LNS with and without bioactive ingredient (β-CyD-OEO only). Moisture of dried complexes ranged 9.1% to 9.7% d.b., whereas water activity 0.35 to 0.412. The complex size and encapsulation efficiency of β-CyD-OEO and β-CyD-CV were 1.5 to 7 μm and 4 to 20 μm, and 86.04 ± 4.48% and 81.39 ± 3.34%, respectively. The bioactive complexes were stable through the gastric and intestinal phases. Bioaccessibility of encapsulated CV ranged 6.0% to 7.7%. Sensory tests revealed no differences (P > 0.05) in color, aroma, and taste between LNS with and without β-CyD-OEO complexes. Functionalization of LNS with β-CyD-OEO is feasible based on in vitro stability and sensory studies. Despite its antiparasitic activities, the addition of oregano essential oil into foods is limited due to its strong flavor and volatility. In this study, we evaluated the encapsulation of oregano essential oil with β-cyclodextrin and its addition into lipid-based nutrition supplements. The results revealed that complex encapsulation efficiency was above 80%. Also, the bioactive complexes were stable under in vitro gastrointestinal conditions. Sensory evaluation of LNS with and without encapsulated essential oil showed no difference in terms of color, aroma, and taste. The functional LNS can both address nutrient insufficiency as well as parasitic infection among malnourished populations in low-resource settings. © 2018 Institute of Food Technologists®.

[Study on molecular recognition technology in active constituents extracted and isolated from Aconitum pendulum].

PubMed

Ma, Xue-Qin; Li, Guo-Shan; Fu, Xue-Yan; Ma, Jing-Zu

2011-03-01

To investigate CD molecular recognition technology applied in active constituents extracted and isolated from traditional Chinese medicine--Aconitum pendulum. The inclusion constant and form probability of the inclusion complex of Aconitum pendulum with p-CD was calculated by UV spectra method. The active constituents of Aconitum pendulum were extracted and isolated by molecular recognition technology. The inclusion complex was identified by UV. The chemical constituents of Aconitum pendulum and inclusion complex was determined by HPLC. The analgesic effects of inclusion complex was investigated by experiment of intraperitoneal injection of acetic acid in rats. The inclusion complex was identified and confirmed by UV spectra method, the chemical components of inclusion complex were simple, and the content of active constituents increased significantly, the analgesic effects of inclusion complex was well. The molecular recognition technology can be used for extracting and isolating active constituents of Aconitum pendulum, and the effects are obvious.

Preparation and structural characterization of corn starch-aroma compound inclusion complexes.

PubMed

Zhang, Shu; Zhou, Yibin; Jin, Shanshan; Meng, Xin; Yang, Liping; Wang, Haisong

2017-01-01

Six corn starch inclusion complexes were synthesized using small nonpolar or weak polar aroma compounds (heptanolide, carvone and menthone) and small polar aroma compounds (linalool, heptanol and menthol). The objectives of this study were to (a) investigate the ability of corn starch to form inclusion complexes with these aroma compounds and (b) characterize the structure of the corn starch inclusion complexes. The resulting inclusion ratios were 75.6, 36.9, 43.8, 91.9, 67.2 and 54.7% for heptanolide, carvone, menthone, linalool, heptanol and menthol respectively. The inclusion complexes had laminated structures with a certain amount of holes or blocky constructions. Compared with gelatinized corn starch, the transition temperatures, peak temperatures and enthalpies of the inclusion complexes were significantly different. The major peak of CO at 1771 cm -1 and significant peak shifts revealed the formation of inclusion complexes. X-ray diffractometry (XRD) analyses revealed that the crystallinity of corn starch-polar aroma compound inclusion complexes increased. Based on cross-polarization magic angle spinning 13 C nuclear magnetic resonance (CP-MAS 13 C NMR) results, novel peaks and chemical shifts were attributed to the presence of small aroma compounds, thereby confirming the formation of corn starch inclusion complexes. Small nonpolar and polar aroma compounds can be complexed to corn starch. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Preparation, characterization and molecular modeling studies of the inclusion complex of Caffeine with Beta-cyclodextrin

NASA Astrophysics Data System (ADS)

Prabu, Samikannu; Swaminathan, Meenakshisundaram; Sivakumar, Krishnamoorthy; Rajamohan, Rajaram

2015-11-01

The formation through supramolecular interaction of a host-guest inclusion complex of caffeine (CA) with nano-hydrophobic cavity beta-cyclodextrin (β-CD) is achieved by a physical mixture, a kneading method and a co-precipitation method. The formation of the inclusion complex of CA with β-CD in solution state is confirmed by UV-visible spectrophotometer, fluorescence spectrophotometer and time-resolved fluorescence spectrophotometer. The stoichiometry of the inclusion complex is 1:1; the imidazole ring and pyrimidine ring of caffeine is deeply entrapped in the beta-cyclodextrin as confirmed by spectral shifts. The Benesi-Hildebrand plot is used to calculate the binding constant of the inclusion complex of CA with β-CD at room temperature. The Gibbs free energy change of the inclusion complex process is calculated and the process is found to be spontaneous. The thermal stability of the inclusion complex of CA with β-CD is analyzed using differential scanning calorimetry. The crystal structure modification of a solid inclusion complex is confirmed by scanning electron microscopy image analysis. The formation of the inclusion complex of CA with β-CD in the solid phase is also confirmed by FT-IR and XRD. The formation of the inclusion complex between CA and β-CD, as confirmed by molecular docking studies, is in good relationship with the results obtained through different experimental methods.

Spectrofluorimetric study of the beta-cyclodextrin-ibuprofen complex and determination of ibuprofen in pharmaceutical preparations and serum.

PubMed

Hergert, L A; Escandar, G M

2003-06-13

The inclusion complexation of ibuprofen in beta-cyclodextrin (beta-CD) has been examined by means of spectrofluorimetry at both acid and alkaline pH. The results suggest that stable 1:1 complexes are formed in both media. The analysis of the pK(a) values for ibuprofen in both the absence and presence of beta-CD (4.12 and 4.66, respectively) suggests that in the inclusion complex the carboxylic group is located outside the cyclodextrin (CD) but interacting with it. Further structural characterization of the complex was carried out by means of am1 semiempiral calculations. Based on the obtained results, a spectrofluorimetric method for the determination of ibuprofen in the presence of beta-CD at 10 degrees C was developed in the range of 4.7-58 mug ml(-1). Better limits of detection (1.6 mug ml(-1)) and quantification (4.7 mug ml(-1)) were obtained in this latter case with respect to those obtained in the absence of beta-CD. The method was satisfactorily applied to the quantification of ibuprofen in pharmaceutical preparations. A novel spectrofluorimetric determination of ibuprofen in the presence of beta-CD was also developed for serum samples at concentration levels between 5 and 70 mug ml(-1). It uses second-order fluorescence excitation-emission matrices coupled to an algorithm based on self-weighted alternating trilinear decomposition (SWATLD), and avoids resorting to separative instrumental analyses.

Two-photon absorption properties of cationic 1,4-bis(styryl)benzene derivative and its inclusion complexes with cyclodextrins.

PubMed

Nag, Okhil Kumar; Nayak, Rati Ranjan; Lim, Chang Su; Kim, In Hong; Kyhm, Kwangseuk; Cho, Bong Rae; Woo, Han Young

2010-07-29

Two-photon absorption properties of 1,4-bis{4'-[N,N-bis(6''-trimethylammoniumhexyl)amino]styryl}benzene tetrabromide (C1) and its inclusion complexes (ICs) with cyclodextrins (CDs) have been studied. Upon complexation with CDs, the absorption spectra of C1 showed a slight red shift, whereas the emission spectra showed a blue shift with concomitant increase in the fluorescence quantum efficiency. A Stern-Volmer study using K(3)Fe(CN)(6) as a quencher revealed significant reduction in the photoinduced charge transfer quenching, in accord with the IC formation. Comparison of the spectroscopic results reveals that C1 forms increasingly more stable ICs in the order C1/beta-CD < C1/gamma-CD < C1/(3gamma:beta)-CD (gamma-CD/beta-CD 3:1, mole ratio). Moreover, the two-photon action cross section of C1 increased from 200 GM for C1 to 400 GM for C1/beta-CD, 460 GM for C1/gamma-CD, and 650 GM for C1/(3gamma:beta)-CD, respectively. Furthermore, the two-photon microscopy images of HeLa cells stained with C1 emitted strong two-photon excited fluorescence in the plasma membrane. These results provide a useful guideline for the development of efficient two-photon materials for bioimaging applications.

Molecular dynamics simulation and TDDFT study of the structures and UV-vis absorption spectra of MCT-β-CD and its inclusion complexes.

PubMed

Lu, Huijuan; Wang, Yujiao; Xie, Xiaomei; Chen, Feifei; Li, Wei

2015-01-01

In this research, the inclusion ratios and inclusion constants of MCT-β-CD/PERM and MCT-β-CD/CYPERM inclusion complexes were measured by UV-vis and fluorescence spectroscopy. The inclusion ratios are both 1:1, and the inclusion constants are 60 and 342.5 for MCT-β-CD/PERM and MCT-β-CD/CYPERM, respectively. The stabilities of inclusion complexes were investigated by MD simulation. MD shows that VDW energy plays a vital role in the stability of inclusion complex, and the destruction of inclusion complex is due to the increasing temperature. The UV-vis absorption spectra of MCT-β-CD and its inclusion complexes were studied by time-dependent density functional theory (TDDFT) method employing BLYP-D3, B3LYP-D3 and M06-2X-D3 functionals. BLYP-D3 well reproduces the UV-vis absorption spectrum and reveals that the absorption bands of MCT-β-CD mainly arise from n→π(∗) and n→σ(∗) transition, and those of inclusion complexes mainly arise from intramolecular charge transfer (ICT). ICT results in the shift of main absorption bands of MCT-β-CD. Copyright © 2015 Elsevier B.V. All rights reserved.

A supramolecular complex between proteinases and beta-cyclodextrin that preserves enzymatic activity: physicochemical characterization.

PubMed

Denadai, Angelo M L; Santoro, Marcelo M; Lopes, Miriam T P; Chenna, Angélica; de Sousa, Frederico B; Avelar, Gabriela M; Gomes, Marco R Túlio; Guzman, Fanny; Salas, Carlos E; Sinisterra, Rubén D

2006-01-01

Cyclodextrins are suitable drug delivery systems because of their ability to subtly modify the physical, chemical, and biological properties of guest molecules through labile interactions by formation of inclusion and/or association complexes. Plant cysteine proteinases from Caricaceae and Bromeliaceae are the subject of therapeutic interest, because of their anti-inflammatory, antitumoral, immunogenic, and wound-healing properties. In this study, we analyzed the association between beta-cyclodextrin (betaCD) and fraction P1G10 containing the bioactive proteinases from Carica candamarcensis, and described the physicochemical nature of the solid-state self-assembled complexes by Fourier transform infrared (FTIR) spectroscopy, thermogravimetry (TG), differential scanning calorimetry (DSC), X-ray powder diffraction (XRD), and nuclear magnetic resonance (NMR), as well as in solution by circular dichroism (CD), isothermal titration calorimetry (ITC), and amidase activity. The physicochemical analyses suggest the formation of a complex between P1G10 and betaCD. Higher secondary interactions, namely hydrophobic interactions, hydrogen bonding and van der Waals forces were observed at higher P1G10 : betaCD mass ratios. These results provide evidence of the occurrence of strong solid-state supramolecular non-covalent interactions between P1G10 and betaCD. Microcalorimetric analysis demonstrates that complexation results in a favorable enthalpic contribution, as has already been described during formation of similar betaCD inclusion compounds. The amidase activity of the complex shows that the enzyme activity is not readily available at 24 hours after dissolution of the complex in aqueous buffer; the proteinase becomes biologically active by the second day and remains stable until day 16, when a gradual decrease occurs, with basal activity attained by day 29. The reported results underscore the potential for betaCDs as candidates for complexing cysteine proteinases, resulting in supramolecular arrays with sustained proteolytic activity.

A matrix-assisted laser desorption/ionization mass spectroscopy method for the analysis of small molecules by integrating chemical labeling with the supramolecular chemistry of cucurbituril.

PubMed

Ding, Jun; Xiao, Hua-Ming; Liu, Simin; Wang, Chang; Liu, Xin; Feng, Yu-Qi

2018-10-05

Although several methods have realized the analysis of low molecular weight (LMW) compounds using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) by overcoming the problem of interference with MS signals in the low mass region derived from conventional organic matrices, this emerging field still requires strategies to address the issue of analyzing complex samples containing LMW components in addition to the LMW compounds of interest, and solve the problem of lack of universality. The present study proposes an integrated strategy that combines chemical labeling with the supramolecular chemistry of cucurbit [n]uril (CB [n]) for the MALDI MS analysis of LMW compounds in complex samples. In this strategy, the target LMW compounds are first labeled by introducing a series of bifunctional reagents that selectively react with the target analytes and also form stable inclusion complexes with CB [n]. Then, the labeled products act as guest molecules that readily and selectively form stable inclusion complexes with CB [n]. This strategy relocates the MS signals of the LMW compounds of interest from the low mass region suffering high interference to the high mass region where interference with low mass components is absent. Experimental results demonstrate that a wide range of LMW compounds, including carboxylic acids, aldehydes, amines, thiol, and cis-diols, can be successfully detected using the proposed strategy, and the limits of detection were in the range of 0.01-1.76 nmol/mL. In addition, the high selectivity of the labeling reagents for the target analytes in conjunction with the high selectivity of the binding between the labeled products and CB [n] ensures an absence of signal interference with the non-targeted LMW components of complex samples. Finally, the feasibility of the proposed strategy for complex sample analysis is demonstrated by the accurate and rapid quantitative analysis of aldehydes in saliva and herbal medicines. As such, this work not only provides an alternative method for the detection of various LMW compounds using MALDI MS, but also can be applied to the selective and high-throughput analysis of LMW analytes in complex samples. Copyright © 2018 Elsevier B.V. All rights reserved.

Microcrystalline dolomite within massive Japan Sea methane hydrate: origin and development ascertained by inclusions within inclusions.

NASA Astrophysics Data System (ADS)

Snyder, G. T.; Kakizaki, Y.; Matsumoto, R.; Suzuki, Y.; Takahata, N.; Sano, Y.; Tanaka, K.; Tomaru, H.; Imajo, T.; Iguchi, A.

2017-12-01

Microcrystalline dolomite grains were recently discovered as inclusions within relatively pure massive gas hydrate recovered from the Joetsu Basin area of the Japan Sea. These grains presumably formed as a consequence of the highly saline conditions in fluid inclusions which developed between coalescing grain boundaries within the growing hydrate. Stable carbon and oxygen isotopic composition of the dolomite is consistent with crystal growth occurring within such fluids. In addition to stable isotopes, we investigate trends in Mg/Ca ratios of the grains as well as the composition of inclusions which exist within the dolomites. Preliminary research shows that these inclusions retain valuable information as to the conditions which existed at the time of formation, as well as the dynamics of these extensive hydrate deposits over time. This study was conducted under the commission from AIST as a part of the methane hydrate research project funded by METI (the Ministry of Economy, Trade and Industry, Japan).

Chlamydia Hijacks ARF GTPases To Coordinate Microtubule Posttranslational Modifications and Golgi Complex Positioning

PubMed Central

Wesolowski, Jordan; Weber, Mary M.; Nawrotek, Agata; Dooley, Cheryl A.; Calderon, Mike; St. Croix, Claudette M.; Hackstadt, Ted; Cherfils, Jacqueline

2017-01-01

ABSTRACT The intracellular bacterium Chlamydia trachomatis develops in a parasitic compartment called the inclusion. Posttranslationally modified microtubules encase the inclusion, controlling the positioning of Golgi complex fragments around the inclusion. The molecular mechanisms by which Chlamydia coopts the host cytoskeleton and the Golgi complex to sustain its infectious compartment are unknown. Here, using a genetically modified Chlamydia strain, we discovered that both posttranslationally modified microtubules and Golgi complex positioning around the inclusion are controlled by the chlamydial inclusion protein CT813/CTL0184/InaC and host ARF GTPases. CT813 recruits ARF1 and ARF4 to the inclusion membrane, where they induce posttranslationally modified microtubules. Similarly, both ARF isoforms are required for the repositioning of Golgi complex fragments around the inclusion. We demonstrate that CT813 directly recruits ARF GTPases on the inclusion membrane and plays a pivotal role in their activation. Together, these results reveal that Chlamydia uses CT813 to hijack ARF GTPases to couple posttranslationally modified microtubules and Golgi complex repositioning at the inclusion. PMID:28465429

Encapsulation and stabilization of β-carotene by amylose inclusion complexes.

PubMed

Kong, Lingyan; Bhosale, Rajesh; Ziegler, Gregory R

2018-03-01

In the present study, we report a novel composition based on amylose (or starch) inclusion complex with an amphiphilic material as an effective encapsulation platform technology to incorporate guests of interest. Specifically, the encapsulation of β-carotene in amylose-surfactant and amylose/starch-ascorbyl palmitate (AscP) inclusion complexes was investigated. Surfactants of different hydrophilicity/lipophilicity were selected to cover a broad range of HLB values. The formation of the inclusion complexes was characterized by X-ray diffraction and differential scanning calorimetry. The ability of amylose-surfactant system to encapsulate β-carotene was dependent on the HLB value of the surfactants, instead of their ability to induce inclusion complexation. The incorporation of β-carotene hindered amylose-surfactant inclusion complex formation, whereas no significant effect was observed on structural and thermal properties of starch-AscP inclusion complex in the presence of β-carotene. The X-ray diffraction pattern of amylose-AscP-β-carotene showed that β-carotene molecules did not crystallize into a separated phase and thus were suggested to be homogeneously immobilized within the polycrystalline amylose-AscP inclusion complexes. During a storage period of six weeks at 20 and 30°C, the stability of β-carotene was improved by encapsulation in starch-AscP inclusion complexes compared with that in physical mixtures of the three components. Copyright © 2017 Elsevier Ltd. All rights reserved.

Removal of volatile organic compounds using amphiphilic cyclodextrin-coated polypropylene.

PubMed

Lumholdt, Ludmilla; Fourmentin, Sophie; Nielsen, Thorbjørn T; Larsen, Kim L

2014-01-01

Polypropylene nonwovens were functionalised using a self-assembled, amphiphilic cyclodextrin coating and the potential for water purification by removal of pollutants was studied. As benzene is one of the problematic compounds in the Water Framework Directive, six volatile organic compounds (benzene and five benzene-based substances) were chosen as model compounds. The compounds were tested as a mixture in order to provide a more realistic situation since the wastewater will be a complex mixture containing multiple pollutants. The volatile organic compounds are known to form stable inclusion complexes with cyclodextrins. Six different amphiphilic cyclodextrin derivatives were synthesised in order to elucidate whether or not the uptake abilities of the coating depend on the structure of the derivative. Headspace gas chromatography was used for quantification of the uptake exploiting the volatile nature of benzene and its derivatives. The capacity was shown to increase beyond the expected stoichiometries of guest-host complexes with ratios of up to 16:1.

Host-guest chemistry of dendrimer-drug complexes: 7. Formation of stable inclusions between acetylated dendrimers and drugs bearing multiple charges.

PubMed

Fang, Min; Zhang, Jiahai; Wu, Qinglin; Xu, Tongwen; Cheng, Yiyun

2012-03-15

Drug molecules bearing multiple charges usually form precipitates with cationic dendrimers, which presents a challenge during the preparation of dendrimer inclusions for these drugs. In the present study, fully acetylated polyamidoamine (PAMAM) dendrimers were proposed as stable vehicles for drug molecules bearing two negative charges such as Congo red and indocyanine green. NMR techniques including (1)H NMR and (1)H-(1)H NOESY were used to characterize the host-guest chemistry of acetylated dendrimer and these guest molecules. The cationic PAMAM dendrimer was found to form a precipitate with Congo red and indocyanine green, but the acetylated one avoided the formation of cross-linking structures in aqueous solutions. NOESY studies revealed the encapsulation of Congo red and indocyanine green within the interior cavities of PAMAM dendrimers at mild acidic conditions and acetylated dendrimers show much stronger ability to encapsulate the guest molecules than cationic ones. Also, UV-vis-NIR studies suggest that acetylated dendrimers significantly improve the photostability of indocyanine green and prevent the formation of indocyanine green J-aggregates in aqueous solutions. The present study provides a new insight into dendrimer-based host-guest systems, especially for those guest molecules bearing multiple charges. © 2012 American Chemical Society

Differentiating Instruction for Disabled Students in Inclusive Classrooms

ERIC Educational Resources Information Center

Broderick, Alicia; Mehta-Parekh, Heeral; Reid, D. Kim

2005-01-01

Differentiating instruction, a comprehensive approach to teaching, enables the successful inclusion of all students, including the disabled, in general-education classrooms. As inclusive educators, we argue that disability is an enacted, interactional process and not an empirical, stable fact or condition. We recommend planning responsive lessons…

A combinatorial approach of inclusion complexation and dendrimer synthesization for effective targeting EGFR-TK.

PubMed

Shende, Pravin; Patil, Sampada; Gaud, R S

2017-07-01

The aim of the present study was to use a combinatorial approach of inclusion complexation and dendrimer synthesization of gefitinib using solvent-free technique for targeting EGFR-TK to treat Non-Small-Cell Lung Cancer (NSCLC). The inclusion complex of gefitinib with β-cyclodextrin was prepared by trituration method. This complex encapsulated G4 PAMAM dendrimers were synthesized by Michael addition and amidation reactions using green chemistry and then PEGylated by conjugation reaction. FTIR and DSC confirmed the formation of inclusion complex of gefitinib and β-cyclodextrin and PEGylation of G4 PAMAM dendrimers. Gefitinib showed higher solubility, encapsulation efficiency and controlled release profile from PEGylated dendrimers compared to inclusion complex. The PEGylated dendrimers of inclusion complex of gefitinib were found to reduce hemolytic toxicity and lesser GI 50 value on Human lung cancer cell line A-549 by effective targeting EGFR-TK. A combinatorial approach of inclusion complexation and dendrimer synthesization is one of the alternative advanced approaches to treat NSCLC. Copyright © 2017 Elsevier B.V. All rights reserved.

Organic compounds in fluid inclusions of Archean quartz-Analogues of prebiotic chemistry on early Earth.

PubMed

Schreiber, Ulrich; Mayer, Christian; Schmitz, Oliver J; Rosendahl, Pia; Bronja, Amela; Greule, Markus; Keppler, Frank; Mulder, Ines; Sattler, Tobias; Schöler, Heinz F

2017-01-01

The origin of life is still an unsolved mystery in science. Hypothetically, prebiotic chemistry and the formation of protocells may have evolved in the hydrothermal environment of tectonic fault zones in the upper continental crust, an environment where sensitive molecules are protected against degradation induced e.g. by UV radiation. The composition of fluid inclusions in minerals such as quartz crystals which have grown in this environment during the Archean period might provide important information about the first organic molecules formed by hydrothermal synthesis. Here we present evidence for organic compounds which were preserved in fluid inclusions of Archean quartz minerals from Western Australia. We found a variety of organic compounds such as alkanes, halocarbons, alcohols and aldehydes which unambiguously show that simple and even more complex prebiotic organic molecules have been formed by hydrothermal processes. Stable-isotope analysis confirms that the methane found in the inclusions has most likely been formed from abiotic sources by hydrothermal chemistry. Obviously, the liquid phase in the continental Archean crust provided an interesting choice of functional organic molecules. We conclude that organic substances such as these could have made an important contribution to prebiotic chemistry which might eventually have led to the formation of living cells.

Formation of inclusion complexes between high amylose starch and octadecyl ferulate via steam jet cooking.

PubMed

Kenar, James A; Compton, David L; Little, Jeanette A; Peterson, Steve C

2016-04-20

Amylose-ligand inclusion complexes represent an interesting approach to deliver bioactive molecules. However, ferulic acid has been shown not to form single helical inclusion complexes with amylose from high amylose maize starch. To overcome this problem a lipophilic ferulic acid ester, octadecyl ferulate, was prepared and complexed with amylose via excess steam jet cooking. Jet-cooking octadecyl ferulate and high amylose starch gave an amylose-octadecyl ferulate inclusion complex in 51.0% isolated yield. X-ray diffraction (XRD) and differential scanning calorimetry (DSC) confirmed that a 61 V-type inclusion complex was formed. Amylose and extraction assays showed the complex to be enriched in amylose (91.9±4.3%) and contain 70.6±5.6mgg(-1) octadecyl ferulate, although, minor hydrolysis (∼4%) of the octadecyl ferulate was observed under the excess steam jet-cooking conditions utilized. This study demonstrates that steam jet cooking is a rapid and scalable process in which to prepare amylose-octadecyl ferulate inclusion complexes. Published by Elsevier Ltd.

Stable divalent germanium, tin and lead amino(ether)-phenolate monomeric complexes: structural features, inclusion heterobimetallic complexes, and ROP catalysis.

PubMed

Wang, Lingfang; Roşca, Sorin-Claudiu; Poirier, Valentin; Sinbandhit, Sourisak; Dorcet, Vincent; Roisnel, Thierry; Carpentier, Jean-François; Sarazin, Yann

2014-03-21

Stable germanium(II) and lead(II) amido complexes {LO(i)}M(N(SiMe3)2) (M = Ge(II), Pb(II)) bearing amino(ether)phenolate ligands are readily available using the proteo-ligands {LO(i)}H of general formula 2-CH2NR2-4,6-tBu2-C6H2OH (i = 1, NR2 = N((CH2)2OCH3)2; i = 2, NR2 = NEt2; i = 3, NR2 = aza-15-crown-5) and M(N(SiMe3)2)2 precursors. The molecular structures of these germylenes and plumbylenes, as well as those of {LO(3)}GeCl, {LO(3)}SnCl and of the congeneric {LO(4)}Sn(II)(N(SiMe3)2) where NR2 = aza-12-crown-4, have been determined crystallographically. All complexes are monomeric, with 3-coordinate metal centres. The phenolate systematically acts as a N^O(phenolate) bidentate ligand, with no interactions between the metal and the O(side-arm) atoms in these cases (for {LO(1)}(-), {LO(3)}(-) and {LO(4)}(-)) where they could potentially arise. For each family, the lone pair of electrons essentially features ns(2) character, and there is little, if any, hybridization of the valence orbitals. Heterobimetallic complexes {LO(3)}M(N(SiMe3)2)·LiOTf, where the Li(+) cation sits inside the tethered crown-ether, were prepared by reaction of {LO(3)}M(N(SiMe3)2) and LiOTf (M = Ge(II), Sn(II)). The inclusion of Li(+) (featuring a close contact with the triflate anion) in the macrocycle bears no influence on the coordination sphere of the divalent tetrel element. In association with iPrOH, the amido germylenes, stannylenes and plumbylenes catalyse the controlled polymerisation of L- and racemic lactide. The activity increases linearly according to Ge(II) ≪ Sn(II) ≪ Pb(II). The simple germylenes generate very sluggish catalysts, but the activity is significantly boosted if the heterobimetallic complex {LO(3)}Ge(N(SiMe3)2)·LiOTf is used instead. On the other hand, with 10-25 equiv. of iPrOH, the plumbylenes afford highly active binary catalysts, converting 1000 or 5000 equiv. of monomer at 60 °C within 3 or 45 min, respectively, in a controlled fashion.

Collapse and Nonlinear Instability of AdS Space with Angular Momentum

NASA Astrophysics Data System (ADS)

Choptuik, Matthew W.; Dias, Óscar J. C.; Santos, Jorge E.; Way, Benson

2017-11-01

We present a numerical study of rotational dynamics in AdS5 with equal angular momenta in the presence of a complex doublet scalar field. We determine that the endpoint of gravitational collapse is a Myers-Perry black hole for high energies and a hairy black hole for low energies. We investigate the time scale for collapse at low energies E , keeping the angular momenta J ∝E in anti-de Sitter (AdS) length units. We find that the inclusion of angular momenta delays the collapse time, but retains a t ˜1 /E scaling. We perturb and evolve rotating boson stars, and find that boson stars near AdS space appear stable, but those sufficiently far from AdS space are unstable. We find that the dynamics of the boson star instability depend on the perturbation, resulting either in collapse to a Myers-Perry black hole, or development towards a stable oscillating solution.

Biosynthesis of ketomycin. (II) biomimetic model for beta-lactamase catalysis: host-guest interactions in cyclodextrin-penicillin inclusion complex

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

Mak, H.W.

The antibiotic ketomycin is formed from shikimic acid via chorismic acid and prephenic acid. Phenylalanine and 2',5'-dihydrophenylalanine derived from shikimic acid are not intermediates in the biosynthesis. Degradation of ketomycin derived from (1,6-/sup 14/C)shikimic acid showed that prephenic acid is converted into ketomycin with stereospecific discrimination between the two enantiotopic edges of the ring, the pro-S-R edge giving rise to the C-2', C-3' side of the cyclohexane ring of ketomycin. The resistance of pathogenic bacteria to the action of ..beta..-lactam antibiotics is mainly ascribed to their ability to produce ..beta..-lactamase to cleave the ..beta..-lactam ring. It is essential to understandmore » the molecular nature of ..beta..-lactamase-penicillin recognition for designing and formulating more effective ..beta..-lactam antibiotics. A biomimetic study of ..beta..-lactamase is therefore initiated. To meet the requirements of hydrophobic and serine protease characteristics of ..beta..-lactamase, ..cap alpha..-cyclodextrin is chosen as a biomimetic model for ..beta..-lactamase. The structural specificity and the chemical dynamics of ..cap alpha..-cyclodextrin-phenoxymethyl penicillin inclusion complex in solid state and in solution have been determined by IR and NMR spectroscopy. The spectral results strongly indicate that the phenyl portion of the phenoxymethyl penicillin forms a stable inclusion complex with the hydrophobic cavity of ..cap alpha..-cyclodextrin in solution as well as in the solid state. Kinetic studies followed by /sup 1/HNMR and HPLC analyses under alkaline condition have shown that the ..cap alpha..-cyclodextrin mimics the catalytic function of serine of ..beta..-lactamase in the stereospecific hydrolysis of the ..beta..-lactam ring of phenoxymethyl penicillin.« less

Mantle Recycling of Crustal Materials through Study of Ultrahigh-Pressure Minerals in Collisional Orogens, Ophiolites, and Xenoliths

NASA Astrophysics Data System (ADS)

Liou, J. G.; Tsujimori, T.; Yang, J.; Zhang, R. Y.; Ernst, W. G.

2014-12-01

Newly recognized ultrahigh-pressure (UHP) mineral occurrences including diamonds in ultrahigh-temperature (UHT) felsic granulites of orogenic belts, in chromitites associated with ophiolitic complexes, and in mafic/ultramafic xenoliths suggest the recycling of crustal materials through profound subduction, mantle upwelling, and return to the Earth's surface. Recycling is supported by unambiguously crust-derived mineral inclusions in deep-seated zircons, chromites, and diamonds from collision-type orogens, from eclogitic xenoliths, and from ultramafic bodies of several Alpine-Himalayan and Polar Ural ophiolites; some such phases contain low-atomic number elements typified by crustal isotopic signatures. Ophiolite-type diamonds in placer deposits and as inclusions in chromitites together with numerous highly reduced minerals and alloys appear to have formed near the mantle transition zone. In addition to ringwoodite and stishovite, a wide variety of nanometric minerals have been identified as inclusions employing state-of-the-art analysis. Reconstitution of now-exsolved precursor UHP phases and recognition of subtle decompression microstructures produced during exhumation reflect earlier UHP conditions. Some podiform chromitites and associated peridotites contain rare minerals of undoubted crustal origin, including Zrn, corundum, Fls, Grt, Ky, Sil, Qtz, and Rtl; the zircons possess much older U-Pb ages than the formation age of the host ophiolites. These UHP mineral-bearing chromitites had a deep-seated evolution prior to extensional mantle upwelling and its partial melting at shallow depths to form the overlying ophiolite complexes. These new findings plus stable isotopic and inclusion characteristics of diamonds provide compelling evidence for profound underflow of both oceanic and continental lithosphere, recycling of biogenic carbon into the lower mantle, and ascent to the Earth's surface through deep mantle ascent.

What Do I Think about Inclusive Education? It Depends on Who Is Asking. Experimental Evidence for a Social Desirability Bias in Attitudes towards Inclusion

ERIC Educational Resources Information Center

Lüke, Timo; Grosche, Michael

2018-01-01

Recently, research has focused on attitudes towards inclusive education, and the majority of studies use questionnaires to measure this vital variable. In two consecutive experiments, we showed that attitudes towards inclusive education are not stable but instead are significantly influenced by social context. We manipulated information on the…

Preparation, characterization, and thermal stability of β-cyclodextrin/soybean lecithin inclusion complex.

PubMed

Wang, Xinge; Luo, Zhigang; Xiao, Zhigang

2014-01-30

β-Cyclodextrin (β-CD), which is widely used to increase the stability, solubility, and bioavailability of guests, can form host-guest inclusion complexes with a wide variety of organic molecules. In this study the β-CD/soybean lecithin inclusion complex was prepared. The effect of reaction parameters such as reaction temperature, reaction time and the molar ratio of β-CD/soybean lecithin on inclusion ratio were studied. The inclusion ratio of the product prepared under the optimal conditions of β-CD/soybean lecithin molar ratio 2:1, reaction temperature 60°C reaction time 2h was 40.2%. The results of UV-vis, DSC, XRD and FT-IR spectrum indicated the formation of inclusion complex. The thermal stability experiment indicated that the thermal stability of soybean lecithin in inclusion complex was significantly improved compared with free soybean lecithin. Copyright © 2013 Elsevier Ltd. All rights reserved.

Chlamydia Hijacks ARF GTPases To Coordinate Microtubule Posttranslational Modifications and Golgi Complex Positioning.

PubMed

Wesolowski, Jordan; Weber, Mary M; Nawrotek, Agata; Dooley, Cheryl A; Calderon, Mike; St Croix, Claudette M; Hackstadt, Ted; Cherfils, Jacqueline; Paumet, Fabienne

2017-05-02

The intracellular bacterium Chlamydia trachomatis develops in a parasitic compartment called the inclusion. Posttranslationally modified microtubules encase the inclusion, controlling the positioning of Golgi complex fragments around the inclusion. The molecular mechanisms by which Chlamydia coopts the host cytoskeleton and the Golgi complex to sustain its infectious compartment are unknown. Here, using a genetically modified Chlamydia strain, we discovered that both posttranslationally modified microtubules and Golgi complex positioning around the inclusion are controlled by the chlamydial inclusion protein CT813/CTL0184/InaC and host ARF GTPases. CT813 recruits ARF1 and ARF4 to the inclusion membrane, where they induce posttranslationally modified microtubules. Similarly, both ARF isoforms are required for the repositioning of Golgi complex fragments around the inclusion. We demonstrate that CT813 directly recruits ARF GTPases on the inclusion membrane and plays a pivotal role in their activation. Together, these results reveal that Chlamydia uses CT813 to hijack ARF GTPases to couple posttranslationally modified microtubules and Golgi complex repositioning at the inclusion. IMPORTANCE Chlamydia trachomatis is an important cause of morbidity and a significant economic burden in the world. However, how Chlamydia develops its intracellular compartment, the so-called inclusion, is poorly understood. Using genetically engineered Chlamydia mutants, we discovered that the effector protein CT813 recruits and activates host ADP-ribosylation factor 1 (ARF1) and ARF4 to regulate microtubules. In this context, CT813 acts as a molecular platform that induces the posttranslational modification of microtubules around the inclusion. These cages are then used to reposition the Golgi complex during infection and promote the development of the inclusion. This study provides the first evidence that ARF1 and ARF4 play critical roles in controlling posttranslationally modified microtubules around the inclusion and that Chlamydia trachomatis hijacks this novel function of ARF to reposition the Golgi complex. Copyright © 2017 Wesolowski et al.

Tautomer preference in PDB complexes and its impact on structure-based drug discovery.

PubMed

Milletti, Francesca; Vulpetti, Anna

2010-06-28

Tautomer enrichment is a key step of ligand preparation prior to virtual screening. In this paper, we have investigated how tautomer preference in various media (water, gas phase, and crystal) compares to tautomer preference at the active site of the protein by analyzing the different possible H-bonding contacts for a set of 13 tautomeric structures. In addition, we have explored the impact of four different protocols for the enumeration of tautomers in virtual screening by using Flap, Glide, and Gold as docking tools on seven targets of the DUD data set. Excluding targets in which the binding does not involve tautomeric atoms (HSP90, p38, and VEGFR2), we found that the average receiver operating characteristic curve enrichment at 10% was 0.25 (Gold), 0.24 (Glide), and 0.50 (Flap) by considering only tautomers predicted to be unstable in water versus 0.41 (Gold), 0.56 (Glide), 0.51 (Flap) by limiting the enumeration process only to the predicted most stable tautomer. The inclusion of all tautomers (stable and unstable) yielded slightly poorer results than considering only the most stable form in water.

New insights on the spectrophotometric determination of melatonin pKa values and melatonin-βCD inclusion complex formation constant

NASA Astrophysics Data System (ADS)

Zafra-Roldán, A.; Corona-Avendaño, S.; Montes-Sánchez, R.; Palomar-Pardavé, M.; Romero-Romo, M.; Ramírez-Silva, M. T.

2018-02-01

Using UV-Vis spectrophotometry a stability study of melatonin at different pH values was done in aqueous media, finding that at acidic pH melatonin is unstable when interacting with the environment, however it becomes stable protecting it from light and oxygen. From the UV-Vis spectra and SQUAD software, melatonin pKa values, in a completely protected aqueous medium, were estimated as 5.777 ± 0.011 and 10.201 ± 0.024. Using the same techniques, the melatonin and β-cyclodextrin inclusion complex formation constants were assessed at pH 3, 7 and 11.5, giving the values of log β = (3.07 ± 0.06), (2.94 ± 0.01) and (3.07 ± 0.06) M- 1, respectively. From the global acidity formation constants and the complexes' formation constants, the molar fractions were determined for each species of MT and MT - βCD, to build the molar fraction-[βCD]-pH 3D diagram and the molar fraction-pH 2D diagrams, where it was possible to observe the predominance of the MT species with and without βCD. A voltammetric study at pH 3, allowed obtaining a value of log β = (3.15 ± 0.01) M- 1, which corroborates that obtained through UV-Vis spectrophotometry, supporting strongly the rationale behind using simple, straightforward techniques.

Stable supersaturated aqueous solutions of silatecan 7-t-butyldimethylsilyl-10-hydroxycamptothecin via chemical conversion in the presence of a chemically modified beta-cyclodextrin.

PubMed

Xiang, Tian-Xiang; Anderson, Bradley D

2002-08-01

A method for obtaining clear supersaturated aqueous solutions for parenteral administration of the poorly soluble experimental anti-cancer drug silatecan 7-t-butyldimethylsilyl-10-hydroxycamptothecin (DB-67) has been developed. Equilibrium solubilities of DB-67 were determined in various solvents and pH values, and in the presence of chemically modified water-soluble beta-cyclodextrins. The stoichiometry and binding constants for complexes of the lactone form of DB-67 and its ring-opened carboxylate with sulfobutyl ether and 2-hydroxypropyl substituted beta-cyclodextrins (SBE-CD and HP-CD) were obtained by solubility and circular dichroism spectroscopy, respectively. Kinetics for the reversible ring-opening of DB-67 in aqueous solution and for lactone precipitation were determined by HPLC with UV detection. Solubilities of DB-67 lactone in various injectable solvent systems were found to be at least one order of magnitude below the target concentration (2 mg/ml). DB-67 forms inclusion complexes with SBE-CD and HP-CD but the solubilization attainable is substantially less than the target concentration. Slow addition of DB-67/ DMSO into 22.2% (w/v) SBE-CD failed to yield stable supersaturated solutions due to precipitation. Stable supersatured solutions were obtained, however, by mixing a concentrated alkaline aqueous solution of DB-67 carboxylate with an acidified 22.2% (w/v) SBE-CD solution. Ring-closure yielded supersaturated solutions that could be lyophilized and reconstituted to clear, stable, supersaturated solutions. The method developed provides an alternative to colloidal dispersions (e.g., liposomal suspensions, emulsions, etc.) for parenteral administration of lipophilic camptothecin analogs.

Spectral study and protein labeling of inclusion complex between dye and calixarene sulfonate.

PubMed

Fei, Xuening; Zhang, Yong; Zhu, Sen; Liu, Lijuan; Yu, Lu

2013-05-01

The host-guest inclusion complex of calix[6]arene sulfonate (SCA6) with thiazole orange (TO) formed in aqueous solution was studied. Absorption and fluorescence techniques were used for the analysis of this inclusion complex. The addition of calixarene sulfonate leads to a decrease in both absorption and fluorescence intensity of the dye, indicating that the inclusion complex was formed. Simultaneously, the inclusion phenomenon of another cyanine dye, Cy3, with calixarene sulfonate was investigated. The stability constant of the two complexes was determined, and the results were compared. The water solubility of TO dye was increased in the presence of calixarene sulfonate, and further protein labeling experiments suggested that this TO-SCA6 complex can act as a fluorescent probe for labeling of biomolecules.

The high water solubility of inclusion complex of taxifolin-γ-CD prepared and characterized by the emulsion solvent evaporation and the freeze drying combination method.

PubMed

Zu, Yuangang; Wu, Weiwei; Zhao, Xiuhua; Li, Yong; Zhong, Chen; Zhang, Yin

2014-12-30

This study selected γ-cyclodextrin (γ-CD) as the inclusion material and prepared inclusion complex of taxifolin-γ-CD by the emulsion solvent evaporation and the freeze drying combination method to achieve the improvement of the solubility and oral bioavailability of taxifolin. We selected ethyl acetate as the oil phase, deionized water as the water phase. The taxifolin emulsion was prepared using adjustable speed homogenate machine in the process of this experiment, whose particle size was related to the concentration of taxifolin solution, the volume ratio of water phase to oil phase, the speed and time of homogenate. We knew through the single-factor test that, the optimum conditions were: the concentration of taxifolin solution was 40 mg/ml, the volume ratio of water phase to oil phase was 1.5, the speed of homogenate was 5,000 rpm, the homogenate time was 11 min. Taxifolin emulsion with a MPS of 142.5 nm was obtained under the optimum conditions, then the high-concentration taxifolin solution (3mg/ml) was obtained by the rotary evaporation process. Finally, the inclusion complex of taxifolin-γ-CD was prepared by vacuum freeze-dry. The characteristics of the inclusion complex of taxifolin-γ-CD were analyzed using SEM, FTIR, XRD, DSC, and TG. The FTIR results analyzed the interaction of taxifolin and γ-CD and determined the molecular structure of the inclusion complex of taxifolin-γ-CD. The analysis results of XRD, DSC and TG indicated that the inclusion complex of taxifolin-γ-CD was obtained and showed significantly different characteristics with taxifolin. In addition, dissolving capability test, antioxidant capacity test, solvent residue test were also carried out. The experimental datas showed that the solubility of inclusion complex of taxifolin-γ-CD at 25°C and 37°C were about 18.5 times and 19.8 times of raw taxifolin, the dissolution rate of inclusion complex of taxifolin-γ-CD were about 2.84 times of raw taxifolin, the bioavailability of inclusion complex of taxifolin-γ-CD increased 3.72 times compared with raw taxifolin, and the antioxidant capacity of inclusion complex of taxifolin-γ-CD was also superior to raw taxifolin. Furthermore, the amounts of residual solvent of the inclusion complex of taxifolin-γ-CD were suitable for pharmaceutical use. These results suggested that inclusion complex of taxifolin-γ-CD may have potential value to become a new oral taxifolin formulation with high solubility. Copyright © 2014 Elsevier B.V. All rights reserved.

Integrated continuous dissolution, refolding and tag removal of fusion proteins from inclusion bodies in a tubular reactor.

PubMed

Pan, Siqi; Zelger, Monika; Jungbauer, Alois; Hahn, Rainer

2014-09-20

An integrated continuous tubular reactor system was developed for processing an autoprotease expressed as inclusion bodies. The inclusion bodies were suspended and fed into the tubular reactor system for continuous dissolving, refolding and precipitation. During refolding, the dissolved autoprotease cleaves itself, separating the fusion tag from the target peptide. Subsequently, the cleaved fusion tag and any uncleaved autoprotease were precipitated out in the precipitation step. The processed exiting solution results in the purified soluble target peptide. Refolding and precipitation yields performed in the tubular reactor were similar to batch reactor and process was stable for at least 20 h. The authenticity of purified peptide was also verified by mass spectroscopy. Productivity (in mg/l/h and mg/h) calculated in the tubular process was twice and 1.5 times of the batch process, respectively. Although it is more complex to setup a tubular than a batch reactor, it offers faster mixing, higher productivity and better integration to other bioprocessing steps. With increasing interest of integrated continuous biomanufacturing, the use of tubular reactors in industrial settings offers clear advantages. Copyright © 2014 Elsevier B.V. All rights reserved.

Curcumin-β-cyclodextrin inclusion complex: stability, solubility, characterisation by FT-IR, FT-Raman, X-ray diffraction and photoacoustic spectroscopy, and food application.

PubMed

Mangolim, Camila Sampaio; Moriwaki, Cristiane; Nogueira, Ana Claudia; Sato, Francielle; Baesso, Mauro Luciano; Neto, Antônio Medina; Matioli, Graciette

2014-06-15

Curcumin was complexed with β-CD using co-precipitation, freeze-drying and solvent evaporation methods. Co-precipitation enabled complex formation, as indicated by the FT-IR and FT-Raman techniques via the shifts in the peaks that were assigned to the aromatic rings of curcumin. In addition, photoacoustic spectroscopy and X-ray diffraction, with the disappearance of the band related to aromatic rings, by Gaussian fitting, and modifications in the spectral lines, respectively, also suggested complex formation. The possible complexation had an efficiency of 74% and increased the solubility of the pure colourant 31-fold. Curcumin-β-CD complex exhibited a sunlight stability 18% higher than the pure colourant. This material was stable to pH variations and storage at -15 and 4°C. With an isothermal heating at 100 and 150°C for 2h, the material exhibited a colour retention of approximately 99%. The application of curcumin-β-CD complex in vanilla ice creams intensified the colour of the products and produced a great sensorial acceptance. Copyright © 2013 Elsevier Ltd. All rights reserved.

Why do the lonely stay lonely? Chronically lonely adolescents' attributions and emotions in situations of social inclusion and exclusion.

PubMed

Vanhalst, Janne; Soenens, Bart; Luyckx, Koen; Van Petegem, Stijn; Weeks, Molly S; Asher, Steven R

2015-11-01

The goal of this study was to identify mechanisms associated with chronic loneliness by examining the effect of adolescents' accumulated history of loneliness on responses to new social situations. Specifically, this study investigated whether attributions and emotions in situations of social inclusion and exclusion differ between chronically lonely adolescents and adolescents with a different loneliness history. A total of 730 adolescents (Mage at Wave 1 = 15.43 years) participated in a 4-wave longitudinal study with annual loneliness assessments. A chronic loneliness trajectory was identified, in addition to low-stable, moderate-stable, moderate-increasing, and high-decreasing loneliness trajectories. At Wave 4, vignettes depicting social inclusion and exclusion were presented, and participants rated a set of attributions and emotions following each vignette. Compared with individuals following other trajectories, chronically lonely adolescents were characterized by hypersensitivity to social exclusion (i.e., higher levels of negative emotions) and hyposensitivity to social inclusion (i.e., lower levels of enthusiasm). Further, chronically lonely adolescents had a stronger tendency to attribute social inclusion to circumstantial factors and social exclusion to internal and stable characteristics. This maladaptive attribution style partially mediated their emotional experiences. Together, results indicate that chronically lonely individuals respond to social situations in ways that may perpetuate rather than reduce their loneliness. (c) 2015 APA, all rights reserved).

Host-guest inclusion system of glycyrrhetic acid with polyamine-β-cyclodextrin: Preparation, characterization, and anticancer activity

NASA Astrophysics Data System (ADS)

Shen, Zhi; Qin, Qi; Liao, Xiali; Yang, Bo

2017-12-01

The inclusion complexation behaviors of glycyrrhetic acid (CTA) with four polyamine-modified β-cyclodextrins (CDs) have been investigated by 1H and 2D NMR, thermal gravimetric analysis, X-ray power diffraction and scanning electron microscopy. The results showed that Glycyrrhetic acid was encapsulated into the cavity of cyclodextrin to form the complexes with 1:1 stoichiometry. The water solubility of GTA was significantly enhanced by inclusion complexation with polyamine-modified β-cyclodextrins. The calculated IC50 values indicated that the antitumor activities of inclusion complexes were better than that of GTA. Satisfactory aqueous solubility, along with high thermal stability of inclusion complexes will be potentially useful for their application on the formulation design of natural medicine.

Prescription Proportion of Pomegranate Extract Gallic Acid Gel by Orthogonal Design

NASA Astrophysics Data System (ADS)

Fan, Gaofu; Liu, Xiushu; Tang, Jie; Gong, Jumei; Fu, Entao; Cai, Yuhua; Xu, Zhenguo

2018-05-01

The aim of the present work was to optimize the formulation of pomegranate extract gallic acid gel by orthogonal design. Using orthogonal design, propylene glycol, carbomer-940 and gel pH level as influencing factors, the evaluation key index was external apearance malleability, uniformity, and eccentric for gel, and the optimum formula was selected. The present findings suggest that 10% propylene glycol, 1.5% Carbopol-940, and gel pH in the range of 4.5∼5.5, and the indexes of the optimal. The inclusion complexes showed that after the orthogonal design, the preparation process was simple, stable and controllable quality, with production feasibility.

Evidence of formation of site-selective inclusion complexation between beta-cyclodextrin and poly(ethylene oxide)-block-poly(propylene oxide)- block-poly(ethylene oxide) copolymers.

PubMed

Tsai, Chi-Chun; Zhang, Wen-Bin; Wang, Chien-Lung; Van Horn, Ryan M; Graham, Matthew J; Huang, Jing; Chen, Yongming; Guo, Mingming; Cheng, Stephen Z D

2010-05-28

A series of inclusion complexes of poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (PEO-b-PPO-b-PEO) with beta-cyclodextrin (beta-CD) was prepared. Their formation, structure, and dynamics were investigated by solution two-dimensional rotating-frame Overhauser effect spectroscopy (2D ROESY) and one-dimensional (1D) and 2D solid-state (13)C NMR. The inclusion complexes between the PEO-b-PPO-b-PEO copolymers and the beta-CDs were formed in aqueous solution and detected by 2D ROESY. The high efficiency of cross polarization and spin diffusion experiments in (13)C solid-state NMR showed that the mobility of the PPO blocks dramatically decreases after beta-CD complexation, indicating that they are selectively incorporated onto the PPO blocks. The hydrophobic cavities of beta-CD restrict the PPO block mobility, which is evidence of the formation of inclusion complexes in the solid state. The 2D wide-line separation NMR experiments suggested that beta-CDs only thread onto the PPO blocks while forming the inclusion complexes. The stoichiometry of inclusion complexes was studied using (1)H NMR, and a 3:1 (PO unit to beta-CD) was found for all inclusion complexes, which indicated that the number of threaded beta-CDs was only dependent on the molecular weight of the PPO blocks. 1D wide angle x-ray diffraction studies demonstrated that the beta-CD in the inclusion complex formed a channel-like structure that is different from the pure beta-CD crystal structure.

Evidence of formation of site-selective inclusion complexation between β-cyclodextrin and poly(ethylene oxide)-block-poly(propylene oxide)- block-poly(ethylene oxide) copolymers

NASA Astrophysics Data System (ADS)

Tsai, Chi-Chun; Zhang, Wen-Bin; Wang, Chien-Lung; Van Horn, Ryan M.; Graham, Matthew J.; Huang, Jing; Chen, Yongming; Guo, Mingming; Cheng, Stephen Z. D.

2010-05-01

A series of inclusion complexes of poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (PEO-b-PPO-b-PEO) with β-cyclodextrin (β-CD) was prepared. Their formation, structure, and dynamics were investigated by solution two-dimensional rotating-frame Overhauser effect spectroscopy (2D ROESY) and one-dimensional (1D) and 2D solid-state C13 NMR. The inclusion complexes between the PEO-b-PPO-b-PEO copolymers and the β-CDs were formed in aqueous solution and detected by 2D ROESY. The high efficiency of cross polarization and spin diffusion experiments in C13 solid-state NMR showed that the mobility of the PPO blocks dramatically decreases after β-CD complexation, indicating that they are selectively incorporated onto the PPO blocks. The hydrophobic cavities of β-CD restrict the PPO block mobility, which is evidence of the formation of inclusion complexes in the solid state. The 2D wide-line separation NMR experiments suggested that β-CDs only thread onto the PPO blocks while forming the inclusion complexes. The stoichiometry of inclusion complexes was studied using H1 NMR, and a 3:1 (PO unit to β-CD) was found for all inclusion complexes, which indicated that the number of threaded β-CDs was only dependent on the molecular weight of the PPO blocks. 1D wide angle x-ray diffraction studies demonstrated that the β-CD in the inclusion complex formed a channel-like structure that is different from the pure β-CD crystal structure.

Complexation reactions in pyridine and 2,6-dimethylpyridine-water system: The quantum-chemical description and the path to liquid phase separation.

PubMed

Chernia, Zelig; Tsori, Yoav

2018-03-14

Phase separation in substituted pyridines in water is usually described as an interplay between temperature-driven breakage of hydrogen bonds and the associating interaction of the van der Waals force. In previous quantum-chemical studies, the strength of hydrogen bonding between one water and one pyridine molecules (the 1:1 complex) was assigned a pivotal role. It was accepted that the disassembly of the 1:1 complex at a critical temperature leads to phase separation and formation of the miscibility gap. Yet, for over two decades, notable empirical data and theoretical arguments were presented against that view, thus revealing the need in a revised quantum-mechanical description. In the present study, pyridine-water and 2,6-dimethylpyridine-water systems at different complexation stages are calculated using high level Kohn-Sham theory. The hydrophobic-hydrophilic properties are accounted for by the polarizable continuum solvation model. Inclusion of solvation in free energy of formation calculations reveals that 1:1 complexes are abundant in the organically rich solvents but higher level oligomers (i.e., 2:1 dimers with two pyridines and one water molecule) are the only feasible stable products in the more polar media. At the critical temperature, the dissolution of the external hydrogen bonds between the 2:1 dimer and the surrounding water molecules induces the demixing process. The 1:1 complex acts as a precursor in the formation of the dimers but is not directly involved in the demixing mechanism. The existence of the miscibility gap in one pyridine-water system and the lack of it in another is explained by the ability of the former to maintain stable dimerization. Free energy of formation of several reaction paths producing the 2:1 dimers is calculated and critically analyzed.

Complexation reactions in pyridine and 2,6-dimethylpyridine-water system: The quantum-chemical description and the path to liquid phase separation

NASA Astrophysics Data System (ADS)

Chernia, Zelig; Tsori, Yoav

2018-03-01

Phase separation in substituted pyridines in water is usually described as an interplay between temperature-driven breakage of hydrogen bonds and the associating interaction of the van der Waals force. In previous quantum-chemical studies, the strength of hydrogen bonding between one water and one pyridine molecules (the 1:1 complex) was assigned a pivotal role. It was accepted that the disassembly of the 1:1 complex at a critical temperature leads to phase separation and formation of the miscibility gap. Yet, for over two decades, notable empirical data and theoretical arguments were presented against that view, thus revealing the need in a revised quantum-mechanical description. In the present study, pyridine-water and 2,6-dimethylpyridine-water systems at different complexation stages are calculated using high level Kohn-Sham theory. The hydrophobic-hydrophilic properties are accounted for by the polarizable continuum solvation model. Inclusion of solvation in free energy of formation calculations reveals that 1:1 complexes are abundant in the organically rich solvents but higher level oligomers (i.e., 2:1 dimers with two pyridines and one water molecule) are the only feasible stable products in the more polar media. At the critical temperature, the dissolution of the external hydrogen bonds between the 2:1 dimer and the surrounding water molecules induces the demixing process. The 1:1 complex acts as a precursor in the formation of the dimers but is not directly involved in the demixing mechanism. The existence of the miscibility gap in one pyridine-water system and the lack of it in another is explained by the ability of the former to maintain stable dimerization. Free energy of formation of several reaction paths producing the 2:1 dimers is calculated and critically analyzed.

Formation of inclusion complexes between high amylose starch and octadecyl ferulate via steam jet cooking

USDA-ARS?s Scientific Manuscript database

Amylose can form inclusion complexes with guest molecules and represents an interesting approach to deliver bioactive molecules. However, ferulic acid has been shown not to form single helical inclusion complexes with amylose. To overcome this problem a ferulic acid ester, octadecyl ferulate, posses...

Preparation, characterization, and in vitro anti-inflammatory evaluation of novel water soluble kamebakaurin/hydroxypropyl-β-cyclodextrin inclusion complex

NASA Astrophysics Data System (ADS)

Raza, Aun; Sun, Huifang; Bano, Shumaila; Zhao, Yingying; Xu, Xiuquan; Tang, Jian

2017-02-01

To enhance the aqueous solubility of kamebakaurin (KA), it was complexed with hydroxypropyl-β-cyclodextrin (HP-β-CD). In this study, the interaction KA with HP-β-CD and their inclusion complex behavior were determined by different characterization techniques such as UV-vis, 1H NMR, FT-IR, PXRD and SEM. All the characterization information proved the development of inclusion complex KA/HP-β-CD, and this inclusion complex demonstrated discriminable spectroscopic characteristics and properties from free compound KA. The results demonstrated that the water solubility of KA was remarkably increased in the presence of HP-β-CD. Furthermore, in vitro anti-inflammatory study showed that inclusion complex KA/HP-β-CD maintained the anti-inflammatory effect of KA. These results demonstrate that HP-β-CD will be promisingly employed in the application of water-insoluble anti-inflammatory phytochemicals such as KA.

Construction of 6-thioguanine and 6-mercaptopurine carriers based on βcyclodextrins and gold nanoparticles.

PubMed

Sierpe, R; Noyong, Michael; Simon, Ulrich; Aguayo, D; Huerta, J; Kogan, Marcelo J; Yutronic, N

2017-12-01

As a novel strategy to overcome some of the therapeutic disadvantages of 6-thioguanine (TG) and 6-mercaptopurine (MP), we propose the inclusion of these drugs in βcyclodextrin (βCD) to form the complexes βCD-TG and βCD-MP, followed by subsequent interaction with gold nanoparticles (AuNPs), generating the ternary systems: βCD-TG-AuNPs and βCD-MP-AuNPs. This modification increased their solubility and improved their stability, betting by a site-specific transport due to their nanometric dimensions, among other advantages. The formation of the complexes was confirmed using powder X-ray diffraction, thermogravimetric analysis and one and two-dimensional NMR. A theoretical study using DFT and molecular modelling was conducted to obtain the more stable tautomeric species of TG and MP in solution and confirm the proposed inclusion geometries. The deposition of AuNPs onto βCD-TG and βCD-MP via sputtering was confirmed by UV-vis spectroscopy. Subsequently, the ternary systems were characterized by TEM, FE-SEM and EDX to directly observe the deposited AuNPs and evaluate their sizes, size dispersion, and composition. Finally, the in vitro permeability of the ternary systems was studied using parallel artificial membrane permeability assay (PAMPA). Copyright © 2017 Elsevier Ltd. All rights reserved.

Study of production and pyrolysis characteristics of sweet orange flavor-β-cyclodextrin inclusion complex.

PubMed

Zhu, Guangyong; Xiao, Zuobing; Zhou, Rujun; Zhu, Yalun

2014-05-25

Flavor plays an important role and has been widely used in foods. Encapsulation can prevent the loss of volatile aromatic ingredients, provide protection and enhance the stability of the flavor. Kinetic and thermodynamic parameters are helpful in understanding the mechanism of molecular recognition between hosts and guests. This work focused on the study of production of a sweet orange flavor-β-cyclodextrin (CD) inclusion complex, and investigated the combination of flavor and β-CD by thermogravimetric analysis. Pyrolysis characteristics, kinetic and thermodynamic parameters of the flavor-β-CD inclusion complex were determined. The results showed that the flavor-β-CD inclusion complexes can form large aggregates in water. During thermal degradation of blank β-CD and flavor-β-CD inclusion complex, three main stages can be distinguished. The thermogravimetric (TG) curve of blank β-CD shows a leveling-off from room temperature to 250°C, while the TG curve of flavor-β-CD inclusion complex is downward sloping in this temperature range. Copyright © 2014 Elsevier Ltd. All rights reserved.

A water-soluble, mucoadhesive quaternary ammonium chitosan-methyl-β-cyclodextrin conjugate forming inclusion complexes with dexamethasone.

PubMed

Piras, Anna Maria; Zambito, Ylenia; Burgalassi, Susi; Monti, Daniela; Tampucci, Silvia; Terreni, Eleonora; Fabiano, Angela; Balzano, Federica; Uccello-Barretta, Gloria; Chetoni, Patrizia

2018-03-30

The ocular bioavailability of lipophilic drugs, such as dexamethasone, depends on both drug water solubility and mucoadhesion/permeation. Cyclodextrins and chitosan are frequently employed to either improve drug solubility or prolong drug contact onto mucosae, respectively. Although the covalent conjugation of cyclodextrin and chitosan brings to mucoadhesive drug complexes, their water solubility is restricted to acidic pHs. This paper describes a straightforward grafting of methyl-β-cyclodextrin (MCD) on quaternary ammonium chitosan (QA-Ch60), mediated by hexamethylene diisocyanate. The resulting product is a water-soluble chitosan derivative, having a 10-atom long spacer between the quaternized chitosan and the cyclodextrin. The derivative is capable of complexing the model drug dexamethasone and stable complexes were also observed for the lyophilized products. Furthermore, the conjugate preserves the mucoadhesive properties typical of quaternized chitosan and its safety as solubilizing excipient for ophthalmic applications was preliminary assessed by in vitro cytotoxicity evaluations. Taken as a whole, the observed features appear promising for future processing of the developed product into 3D solid forms, such as controlled drug delivery systems, films or drug eluting medical devices.

Complexation of morin with three kinds of cyclodextrin. A thermodynamic and reactivity study

NASA Astrophysics Data System (ADS)

Jullian, Carolina; Orosteguis, Teresita; Pérez-Cruz, Fernanda; Sánchez, Paulina; Mendizabal, Fernando; Olea-Azar, Claudio

2008-11-01

Properties of inclusion complexes between morin (M) and β-cyclodextrin (βCD), 2-hydroxypropyl-β-cyclodextrin (HPβCD) and Heptakis (2,6- O-di methyl) β-cyclodextrin (DMβCD) such as aqueous solubility and the association constants of this complex have been determined. The water solubility of morin was increased by inclusion with cyclodextrins. The phase-solubility diagrams drawn from UV spectral measurements are of the A L-type. Also ORAC FL studies were done. An increase in the antioxidant reactivity is observed when morin form inclusion complex with the three cyclodextrin studied. Finally, thermodynamics studies of cyclodextrin complexes indicated that for DMβCD the inclusion is primarily enthalpy-driven process meanwhile βCD and HPβCD are entropy-driven processes. This is corroborated by the different inclusion geometries obtained by 2D-NMR.

Improvement of drug loading onto ion exchange resin by cyclodextrin inclusion complex.

PubMed

Samprasit, Wipada; Rojanarata, Theerasak; Akkaramongkolporn, Prasert; Ngawhirunpat, Tanasait; Sila-on, Warisada; Opanasopit, Praneet

2013-11-01

Ion exchange resins have ability to exchange their counter ions for ionized drug in the surrounding medium, yielding "drug resin complex." Cyclodextrin can be applied for enhancement of drug solubility and stability. Cyclodextrin inclusion complex of poorly water-soluble NSAIDs, i.e. meloxicam and piroxicam, was characterized and its novel application for improving drug loading onto an anionic exchange resin, i.e. Dowex® 1×2, was investigated. β-Cyclodextrin (β-CD) and hydroxypropyl β-cyclodextrin (HP-β-CD) were used for the preparation of inclusion complex with drugs in solution state at various pH. The inclusion complex was characterized by phase solubility, continuous variation, spectroscopic and electrochemistry methods. Then, the drug with and without cyclodextrin were equilibrated with resin at 1:1 and 1:2 weight ratio of drug and resin. Solubility of the drugs was found to increase with increasing cyclodextrin concentration and pH. The increased solubility was explained predominantly due to the formation of inclusion complex at low pH and the increased ionization of drug at high pH. According to characterization studies, the inclusion complex was successfully formed with a 1:1 stoichiometry. The presence of cyclodextrin in the loading solution resulted in the improvement of drug loading onto resin. Enhancing drug loading onto ion-exchange resin via the formation of cyclodextrin inclusion complex is usable in the development of ion-exchange based drug delivery systems, which will beneficially reduce the use of harmful acidic or basic and organic chemicals.

Preliminary mineralogic, fluid inclusion, and stable isotope study of the Mahd adh Dhahab gold mine, Kingdom of Saudi Arabia

USGS Publications Warehouse

Rye, Robert O.; Hall, W.E.; Cunningham, C.G.; Czamanske, G.K.; Afifi, A.M.; Stacey, J.S.

1983-01-01

The Mahd adh Dhahab mine, located about 280 km northeast of Jiddah, Kingdom of Saudi Arabia, has yielded more than 2 million ounces of gold from periodic production during the past 3,000 years. A new orebody on the southern side of the ancient workings, known as the South orebody, is being developed by Gold Fields-Mahd adh Dhahab Limited. A suite of samples was collected from the newly exposed orebody for preliminary mineralogic, stable isotope, fluid inclusion, and geochemical studies. The Mahd adh Dhahab deposit is in the carapace of a Proterozoic epizonal rhyolite stock that domed pyroclastic and metasedimentary rocks of the Proterozoic Halaban group. Ore of gold, silver, copper, zinc, tellurium, and lead is associated with north-trending, steeply dipping quartz veins in a zone 1,000 m long and 400 m wide. The veins include an assemblage of quartz-chlorite-pyrite-hematite-chalcopyrite-sphalerite-precious metals, which is similar to the mineral assemblage at the epithermal deposit at Creede, Colorado. The primary ore contains abundant chalcopyrite, sphalerite, and pyrite in addition to a complex precious metal assemblage. Gold and silver occur principally as minute grains of telluride minerals disseminated in quartz-chlorite-hematite and as inclusions in chalcopyrite and sphalerite. Telluride minerals include petzite, hessite, and sylvanite. Free gold is present but not abundant. All of the vein-quartz samples contained abundant, minute inclusions of both low-density, vapor-rich fluids and liquid-rich fluids. Primary fluid inclusions yielded homogenization temperatures of from 110? to 238? C. Preliminary light-stable isotope studies of the sulfide minerals and quartz showed that all of the d34S values are between 1.2 and 6.3 per mil, which is a typical range for hydrothermal sulfide minerals that derive their sulfur from an igneous source. The data-suggest that the sulfide sulfur isotope geochemistry was controlled by exchange with la large sulfur isotope reservoir at depth. The d18O values of all stages of vein quartz in the South orebody range between 8.5 and 11.1 per mil. This range is similar to that for quartz from the North orebody and indicates that the hydrothermal system consisted of dominantly exchanged meteoric water, which was uniform in temperature and d18O content throughout the area during the entire period of mineralization. Lead isotope analyses of two galena samples indicate that the lead in the South orebody is less radiogenic than that from the North orebody and confirm that the lead was derived from oceanic crust approximately 700 Ma ago.

Supramolecular structure of glibenclamide and β-cyclodextrins complexes.

PubMed

Lucio, David; Irache, Juan Manuel; Font, María; Martínez-Ohárriz, María Cristina

2017-09-15

Glibenclamide is an antidiabetic drug showing low bioavailability as consequence of its low solubility. To solve this drawback, the interaction with cyclodextrins has been proposed. The formation of GB-βCDs inclusion complexes was carried out using different methods, βCD derivatives and drug-to-cyclodextrin ratios. The structures of the corresponding complexes have been studied by molecular modelling, X-ray diffraction and differential thermal analysis. The dissolution behavior of inclusion complexes has been compared to that of pure GB. Dimeric inclusion complexes were obtained with different CD disposals, head-to-head for βCD and head-to-tail for HPβCD and RMβCD. Amorphous inclusion complexes were obtained by employing methods of freeze-drying or coevaporation in ammonia-water. However, crystalline structures were formed by kneading and coevaporation in ethanol/water in the case of GB-βCD complexes. The arrangement of these structures depended on the GB:βCD ratio, yielding cage type structures for 1:3 and 1:5 ratios and channel-type structures for higher GB contents. The amount of GB released and its dissolution rate was considerably increased by the use of amorphous inclusion complexes; whereas, slower GB release rates were found from crystalline inclusion complexes formed by kneading or coevaporation in ethanol/water. In addition, it was found that the porous structure strongly conditioned the GB dissolution rate from crystalline products. Copyright © 2017 Elsevier B.V. All rights reserved.

Interaction between carboplatin and cucurbit[7]uril studied by means of multinuclear NMR spectroscopy and DFT calculations

NASA Astrophysics Data System (ADS)

Mirzaeva, I. V.; Moroz, N. K.; Andrienko, I. V.; Kovalenko, E. A.

2018-07-01

Encapsulation of platinum-based antitumor drugs into host molecules is a rapidly growing field, as it provides the potential to reduce the toxicity and overcome tumor resistance issues, with cucurbit[n]uril family being a very promising class of potential hosts. Although, previously it was reported that carboplatin, a second generation platinum-based antitumor drug, did not interact with cucurbit[7]uril, in this work, we have observed such an interaction by means of multinuclear NMR spectroscopy. Apparently, upon the interaction with cucurbit[7]uril in aqueous solution, carboplatin decomposes into 1,1-cyclobutane dicarboxylic acid and some cis-PtL2(NH3)2 (L = H2O or OH-) which forms a relatively stable inclusion complex with cucurbit[7]uril. DFT calculations of the geometry of hypothetical complexes and NMR shielding of 1H, 13C, and 195Pt nuclei help with interpretation of the experimental NMR results.

Inclusion complexes of β-cyclodextrin-dinitrocompounds as UV absorber for ballpoint pen ink.

PubMed

Srinivasan, Krishnan; Radhakrishnan, S; Stalin, Thambusamy

2014-08-14

2,4-Dinitrophenol (2,4-DNP), 2,4-dinitroaniline (2,4-DNA), 2,6-dinitroaniline (2,6-DNA) and 2,6-dinitrobenzoic acid (2,6-DNB) has appeared for the UV absorption bands in different wavelength region below 400 nm, a combination of these dinitro aromatic compounds gave the broad absorption spectra within the UV region. The absorption intensities have been increased by preparation of the inclusion complex of dinitro compounds with β-cyclodextrin (β-CD). Prepared inclusion complexes are used to improve the UV protection properties of the ball point pen ink against photo degradation. The formation of solid inclusion complexes was characterized by FT-IR, and (1)H NMR spectroscopy. The UV protecting properties of these inclusion complexes were calculated their sun protection factor (SPF) is also discussed. The stability of the ballpoint pen ink has been confirmed by UV-Visible spectroscopic method. Copyright © 2014 Elsevier B.V. All rights reserved.

Theoretical and Experimental Study of Inclusion Complexes of β-Cyclodextrins with Chalcone and 2',4'-Dihydroxychalcone.

PubMed

Sancho, Matias I; Andujar, Sebastian; Porasso, Rodolfo D; Enriz, Ricardo D

2016-03-31

The inclusion complexes formed by chalcone and 2',4'-dihydroxychalcone with β-cyclodextrin have been studied combining experimental (phase solubility diagrams, Fourier transform infrared spectroscopy) and molecular modeling (molecular dynamics, quantum mechanics/molecular mechanics calculations) techniques. The formation constants of the complexes were determined at different temperatures, and the thermodynamic parameters of the process were obtained. The inclusion of chalcone in β-cyclodextrin is an exothermic process, while the inclusion of 2',4'-dihydroxychalcone is endothermic. Free energy profiles, derived from umbrella sampling using molecular dynamics simulations, were constructed to analyze the binding affinity and the complexation reaction at a molecular level. Hybrid QM/MM calculations were also employed to obtain a better description of the energetic and structural aspects of the complexes. The intermolecular interactions that stabilize both inclusion complexes were characterized by means of quantum atoms in molecules theory and reduce density gradient method. The calculated interactions were experimentally observed using FTIR.

Effective electromagnetic properties of microheterogeneous materials with surface phenomena

NASA Astrophysics Data System (ADS)

Levin, Valery; Markov, Mikhail; Mousatov, Aleksandr; Kazatchenko, Elena; Pervago, Evgeny

2017-10-01

In this paper, we present an approach to calculate the complex dielectric permittivity of a micro-heterogeneous medium composed of non-conductive solid inclusions embedded into the conductive liquid continuous host. To take into account the surface effects, we approximate the inclusion by a layered ellipsoid consisting of a dielectric core and an infinitesimally thin outer shell corresponding to an electrical double layer (EDL). To predict the effective complex dielectric permittivity of materials with a high concentration of inclusions, we have modified the Effective Field Method (EFM) for the layered ellipsoidal particles with complex electrical properties. We present the results of complex permittivity calculations for the composites with randomly and parallel oriented ellipsoidal inclusions. To analyze the influence of surface polarization, we have accomplished modeling in a wide frequency range for different existing physic-chemical models of double electrical layer. The results obtained show that the tensor of effective complex permittivity of a micro-heterogeneous medium with surface effects has complicate dependences on the component electrical properties, spatial material texture, and the inclusion shape (ellipsoid aspect ratio) and size. The dispersion of dielectric permittivity corresponds to the frequency dependence for individual inclusion of given size, and does not depend on the inclusion concentration.

Enantiodifferentiation of chiral baclofen by β-cyclodextrin using capillary electrophoresis: A molecular modeling approach

NASA Astrophysics Data System (ADS)

Suliman, FakhrEldin O.; Elbashir, Abdalla A.

2012-07-01

Using capillary electrophoresis baclofen (BF) enantiomers were separated only in the presence of β-cyclodextrin (βCD) as a chiral selector when added to the background electrolyte. Proton nuclear magnetic resonance and electrospray ionization mass spectrometry (ESI-MS) techniques were used to determine the structure of the BF-βCD inclusion complexes. From the MS data BF was found to form a 1:1 complex with α- and βCD, while the NMR data suggest location of the aromatic ring of BF into the cyclodextrin cavity. A molecular modeling study, using the semiempirical PM6 calculations was used to investigate the mechanism of enantiodifferentiation of BF with cyclodextrins. Optimization of the structures of the complexes by PM6 method indicated that separation is obtained in the presence of β-CD due to a large binding energy difference (ΔΔE) of 46.8 kJ mol-1 between S-BF-βCD and R-BF-βCD complexes. In the case of αCD complexes ΔΔE was 1.3 kJ mol-1 indicating poor resolution between the two enantiomers. Furthermore, molecular dynamic simulations show that the formation of more stable S-BF-βCD complex compared to R-BF-β-CD complex is primarily due to differences in intermolecular hydrogen bonding.

Inclusion complexes of yellow bell pepper pigments with β-cyclodextrin: preparation, characterisation and application as food natural colorant.

PubMed

Lobo, Francine Albernaz Tf; Silva, Vitoria; Domingues, Josiane; Rodrigues, Silvana; Costa, Valéria; Falcão, Deborah; de Lima Araújo, Kátia G

2018-05-01

This work aimed to prepare inclusion complexes using yellow bell pepper pigments and β-cyclodextrin by two different procedures (method A, ultrasonic homogenisation; method B, kneading), to characterise them and evaluate their colour stability in an isotonic beverage model. The extract/β-cyclodextrin ratio was 1:2 for both inclusion methodologies evaluated. The formed extract-β-cyclodextrin complexes and a physical mixture of extract and β-cyclodextrin were evaluated by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). Both methodologies resulted in good complex yield and inclusion efficiency. The colour indices L* (lightness), a* (green/red) and b* (blue/yellow) of isotonic drinks added with the complexes were measured during storage under irradiance (1400 lx) and in the absence of light at temperatures between 25 and 31 °C for 21 days. The complex obtained by inclusion method B promoted better colour protection for the beverage compared with the use of the crude extract, showing that the molecular inclusion of yellow bell pepper carotenoids can provide good results for that purpose. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Production, Characterization, and Stability of Orange or Eucalyptus Essential Oil/β-Cyclodextrin Inclusion Complex.

PubMed

Kringel, Dianini Hüttner; Antunes, Mariana Dias; Klein, Bruna; Crizel, Rosane Lopes; Wagner, Roger; de Oliveira, Roberto Pedroso; Dias, Alvaro Renato Guerra; Zavareze, Elessandra da Rosa

2017-11-01

The aim of this study was to produce and characterize inclusion complexes (IC) between β-cyclodextrin (β-CD) and orange essential oil (OEO) or eucalyptus essential oil (EEO), and to compare these with their pure compounds and physical mixtures. The samples were evaluated by chemical composition, morphology, thermal stability, and volatile compounds by static headspace-gas chromatography (SH-GC). Comparing the free essential oil and physical mixture with the inclusion complex, of both essential oils (OEO and EEO), it was observed differences occurred in the chemical composition, thermal stability, and morphology. These differences show that there was the formation of the inclusion complex and demonstrate the necessity of the precipitation method used to guarantee the interaction between β-CD and essential oils. The slow loss of the volatile compounds from both essential oils, when complexed with β-CD, showed a higher stability when compared with their physical mixtures and free essential oils. Therefore, the results showed that the chemical composition, molecular size, and structure of the essential oils influence the characteristics of the inclusion complexes. The application of the β-CD in the formation of inclusion complexes with essential oils can expand the potential applications in foods. © 2017 Institute of Food Technologists®.

Fluid inclusion and stable isotopes studies of epithermal gold-bearing veins in the SE Afar Rift (Djibouti)

NASA Astrophysics Data System (ADS)

Moussa, N.; Boiron, M. C.; Grassineau, N.; Fouquet, Y.; Le Gall, B.; Mohamed, J.

2015-12-01

The Afar rift results from the interaction of a number of actively-propagating tectono-magmatic axes. Recent field investigations in the SE Afar rift have emphasized the importance of hydrothermal system in rift-related volcanic complexes. Mineralization occur as gold-silver bearing veins and are associated with felsic volcanism. Late carbonate veins barren of sulfides and gold are common. The morphologies and textures of quartz show crustiform colloform banding, massive and breccias. Microthermometric measurements were made on quartz-hosted two phases (liquid + vapor) inclusions; mean homogenization temperature range from 150°C to 340°C and ice-melting temperatures range from -0.2° to 1.6°C indicating that inclusion solutions are dilute and contain 0.35 to 2.7 equivalent wt. % NaCl. Furthermore, δ18O and δ13C values from calcite range from 3.7 to 26.6 ‰ and -7.5 to 0.3‰, respectively. The presence of platy calcite and adularia indicate that boiling condition existed. This study shows that precious-metal deposition mainly occurred from hydrothermal fluids at 200°C at around 300 and 450 m below the present-day surface in a typical low-sulphidation epithermal environment.

Ketoprofen-β-cyclodextrin inclusion complexes formation by supercritical process technology

NASA Astrophysics Data System (ADS)

Sumarno, Rahim, Rizki; Trisanti, Prida Novarita

2017-05-01

Ketoprofen was a poorly soluble which anti-inflammatory, analgesic and antipyretic drug, solubility of which can be enchanced by form complexation with β-cyclodextrin. Besides that, the inclusion complex reduces the incidence of gastrointestinal side effect of drug. The aims of this research are to study the effect of H2O concentration in the supercritical carbondioxide and operation condition in the formation of ketoprofen-β-Cyclodextrin inclusion complex. This research was began by dissolved H2O in supercritical CO2 at 40°C and various saturation pressures. Then, dissolved H2O contacted with (1:5 w/w) ketoprofen-β-Cyclodextrin mixture at 50°C and various operation pressures. It called saturation process. Saturation was done for ±2 hours with agitation process and continued by decompression process. The products were characterized by drug Release, Differential Scanning Calorimetry (DCS) dan Scanning Electron Microscopy (SEM) analyses. The percentage from this work were 76,82%-89,99% for inclusion complexes. The percentage drug release of ketoprofen were 82,83%-88,36% on various inclusion pressure and various inclusion period.

Inclusion complex effect on the bioavailability of clotrimazole from poloxamer-based solid suppository.

PubMed

Balakrishnan, Prabagar; Song, Chung Kil; Cho, Hyun-Jong; Yang, Su-Geun; Kim, Dae Duk; Yong, Chul Soon; Choi, Han-Gon

2012-07-01

To study the effect of β-cyclodextrin (βCD) inclusion complex on the bioavailability of clotrimazole from poloxamer-based suppository, formulations composed of P 188, propylene glycol and different molar ratio of clotrimazole-βCD inclusion complex were prepared. Clotrimazole (1%) has been formulated in a suppository using the thermo sensitive polymer P188 (70%) together with propylene glycol (30%). To increase its aqueous solubility, clotrimazole was incorporated as its inclusion complex at various molar ratios with βCD (1:0.25, 1:0.5, 1:1, and 1:2). The inclusion complex was characterized by differential scanning calorimetry (DSC), XRD and phase solubility studies. It was observed that the complexation with βCD, particularly at high molar ratio (F3 (1:1) and F4 (1:2)) decreased the release profile of clotrimazole considerably. However, suppositories containing inclusion complex at low molar ratio (F1 (1:0.25) and F2 (1:0.5)) showed excellent release profile compared to control formulation. In vivo study in rats at 15 mg/Kg dose showed that the F1 and F2 (82.39 ± 15.40 and 67.05 ± 8.79, respectively) significantly increased the AUC compared to that of F3 (41.48 ± 11.51), F4 (23.34 ± 8.37) and control (46.7 ± 7.87) suppositories. Thus, the suppositories containing inclusion complexes prepared at low drug to βCD molar ratio (F1) could be a potential suppository formulation to increase the bioavailability of hydrophobic drugs such as clotrimazole.

Empirical, thermodynamic and quantum-chemical investigations of inclusion complexation between flavanones and (2-hydroxypropyl)-cyclodextrins.

PubMed

Liu, Benguo; Li, Wei; Nguyen, Tien An; Zhao, Jian

2012-09-15

The inclusion complexation of (2-hydroxypropyl)-cyclodextrins with flavanones was investigated by phase solubility measurements, as well as thermodynamic and quantum chemical methods. Inclusion complexes were formed between (2-hydroxypropyl)-α-cyclodextrin (HP-α-CD), (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD), (2-hydroxypropyl)-γ-cyclodextrin (HP-γ-CD) and β-cyclodextrin (β-CD) and four flavanones (naringenin, naringin, hesperetin and dihydromyricetin) in aqueous solutions and their phase solubility was determined. For all the flavanones, the stability constants of their complexes formed with different CDs followed the rank order: HP-β-CD (MW 1540)>HP-β-CD (MW 1460)>HP-β-CD (MW 1380)>β-CD>HP-γ-CD>HP-α-CD. Experimental results and quantum chemical calculations showed that the ability of flavanones to form inclusion complex with (2-hydroxypropyl)-cyclodextrins was determined by both the steric effect and hydrophobicity of the flavanones. For flavanones that have similar molecular volumes, the hydrophobicity of the molecule was the main determining factor of its ability to form inclusion complexes with HP-β-CD, and the hydrophobicity parameter Log P is highly correlated with the stability constant of the complexes. Results of thermodynamic study demonstrated that hydrophobic interaction is the main driving force for the formation process of the flavanone-CD inclusion complexes. Quantum chemical analysis of the most active hydroxyl groups and HOMO (the highest occupied molecular orbital) showed that the B ring of the flavanones was most likely involved in hydrogen bonding with the side groups in the cavity of the CDs, through which the inclusion complex was stabilised. Copyright © 2012 Elsevier Ltd. All rights reserved.

Nucleophilic reactivity of a series of peroxomanganese(III) complexes supported by tetradentate aminopyridyl ligands.

PubMed

Geiger, Robert A; Chattopadhyay, Swarup; Day, Victor W; Jackson, Timothy A

2011-02-28

Peroxomanganese(iii) adducts have been postulated as important intermediates in manganese-containing enzymes and small molecule oxidation catalysts. Synthetic peroxomanganese(iii) complexes are known to be nucleophilic and facilitate aldehyde deformylation, offering a convenient way to compare relative reactivities of complexes supported by different ligands. In this work, tetradentate dipyridyldiazacycloalkane ligands with systematically perturbed steric and electronic properties were used to generate a series of manganese(ii) and peroxomanganese(iii) complexes. X-Ray crystal structures of five manganese(ii) complexes all show the ligands bound to give trans complexes. Treatment of these Mn(II) precursors with H(2)O(2) and Et(3)N in MeCN at -40 °C results in the formation of peroxomanganese(iii) complexes that differ only in the identity of the pyridine ring substituent and/or the number of carbons in the diazacycloalkane backbone. To determine the effects of small ligand perturbations on the reactivity of the peroxo group, the more thermally stable peroxomanganese(iii) complexes were reacted with cyclohexanecarboxaldehyde. For these complexes, the rate of deformylation does not correlate with the expected nucleophilicity of the peroxomanganese(iii) unit, as the inclusion of methyl substituents on the pyridines affords slower deformylation rates. It is proposed that adding methyl-substituents to the pyridines, or increasing the number of carbons on the diazacycloalkane, sterically hinders nucleophilic attack of the peroxo ligand on the carbonyl carbon of the aldehyde.

Exploring inclusion complexes of ionic liquids with α- and β- cyclodextrin by NMR, IR, mass, density, viscosity, surface tension and conductance study

NASA Astrophysics Data System (ADS)

Barman, Biraj Kumar; Rajbanshi, Biplab; Yasmin, Ananya; Roy, Mahendra Nath

2018-05-01

The formation of the host-guest inclusion complexes of ionic liquids namely [BMIm]Cl and [HMIm]Cl with α-CD and β-CD were studied by means of physicochemical and spectroscopic methods. Conductivity and surface tension study were in good agreement with the 1H NMR and FT-IR studies which confirm the formation of the inclusion complexes. The Density and viscosity study also supported the formation of the ICs. Further the stoichiometry was determined 1:1 for each case and the association constants and thermodynamic parameters derived supported the most feasible formation of the [BMIm]Cl- β-CD inclusion complex.

Enhancement of the release of azelaic acid through the synthetic membranes by inclusion complex formation with hydroxypropyl-beta-cyclodextrin.

PubMed

Manosroi, Jiradej; Apriyani, Maria Goretti; Foe, Kuncoro; Manosroi, Aranya

2005-04-11

The aim of this study was to investigate the release rates of azelaic acid and azelaic acid-hydroxypropyl-beta-cyclodextrin (HPbetaCD) inclusion complex through three types of synthetic membranes, namely cellophane, silicone and elastomer membranes. Solid inclusion complexes of azelaic acid-HPbetaCD at the molar ratio of 1:1 were prepared by coevaporation and freeze-drying methods, subsequently characterized by differential scanning calorimetry, X-ray diffractometry and dissolution studies. Solid inclusion complex obtained by coevaporation method which exhibited the inclusion of azelaic acid in the HPbetaCD cavity and gave the highest dissolution rate of azelaic acid was selected for the release study. Release studies of azelaic acid and this complex through the synthetic membranes were conducted using vertical Franz diffusion cells at 30 degrees C for 6 days. The release rates of azelaic acid through the synthetic membranes were enhanced by the formation of inclusion complex with HPbetaCD at the molar ratio of 1:1, with the increasing fluxes of about 41, 81 and 28 times of the uncomplexed system in cellophane, silicone and elastomer membranes, respectively. The result from this study can be applied for the development of azelaic acid for topical use.

Formation of β-Cyclodextrin inclusion compound with doxycycline: A theoretical approach

NASA Astrophysics Data System (ADS)

Peraro, Cristian R.; Anconi, Amanda C. S. A.; Anconi, Cleber P. A.

2018-01-01

Recently, the inclusion compound formed by doxycycline and modified CD was investigated. In the inclusion compound, the unstable site of doxycycline was protected by the hydrophobic CD cavity. However, the guest arrangement inside CD cavity has not identified. In some situations, the correlation between protons of the guest and host in a 2D-ROESY experiment can be compatible with head and tail spatial arrangements. In the present work, the most stable guest spatial arrangement for the inclusion of doxycycline into β-CD was evaluated at B97-D/6-311++(2d,p) level of theory. For sake of comparison, tetracycline inclusion compound was also studied.

Clove essential oil-in-cyclodextrin-in-liposomes in the aqueous and lyophilized states: From laboratory to large scale using a membrane contactor.

PubMed

Sebaaly, Carine; Charcosset, Catherine; Stainmesse, Serge; Fessi, Hatem; Greige-Gerges, Hélène

2016-03-15

This work is dedicated to prepare liposomal dry powder formulations of inclusion complexes of clove essential oil (CEO) and its main component eugenol (Eug). Ethanol injection method and membrane contactor were applied to prepare liposomes at laboratory and large scale, respectively. Various liposomal formulations were tested: (1) free hydroxypropyl-β-cyclodextrin loaded liposomes; (2) drug in hydroxypropyl-β-cyclodextrin in liposomes (DCL); (3) DCL2 obtained by double loading technique, where the drug is added in the organic phase and the inclusion complex in the aqueous phase. Liposomes were characterized for their particle size, polydispersity index, Zeta potential, morphology, encapsulation efficiency of CEO components and Eug loading rate. Reproducible results were obtained with both injection devices. Compared to Eug-loaded liposomes, DCL and DCL2 improved the loading rate of Eug and possessed smaller vesicles size. The DPPH(•) scavenging activity of Eug and CEO was maintained upon incorporation of Eug and CEO into DCL and DCL2. Contrary to DCL2, DCL formulations were stable after 1 month of storage at 4°C and upon reconstitution of the dried lyophilized cakes. Hence, DCL in aqueous and lyophilized forms, are considered as a promising carrier system to preserve volatile and hydrophobic drugs enlarging their application in cosmetic, pharmaceutical and food industries. Copyright © 2015 Elsevier Ltd. All rights reserved.

Stable isotope study of antimony deposits in the Muratdagi region, western Turkey

NASA Astrophysics Data System (ADS)

Gokçe, A.; Spiro, B.

1994-09-01

The Muratdagi region is rich in antimony deposits having the following common characteristics: post Miocene age, location on the down-thrown blocks next to normal faults, in the vicinity of active or fossil thermal springs, and in contact with carbonate rocks. The isotopic composition of — 7‰. SMOW of the mineralizing fluid calculated from the measured ° 18O of quartz and the fluid inclusion microthermometry, is indicative of meteoric water origin. The ° 13C of the inclusion CO2 of — 19.1 to — 25.4‰ PDB is indicative of interaction with organic material-graphite. The ° 34S of stibnite — 3.6 to — 0.7‰ is, in view of the mineral assemblage, indicative of magmatic origin of the sulphur. A tightly confined set of structural, lithological, hydrological and geochemical features define a sequence of geochemical processes; formation of acid and reducing fluid, leaching and transport of antimony complexes and precipitation of stibnite within defined lithological units. The set of processes seems to have taken place within a space of 5000 m lateral and 1000 m vertical extension.

Modeling and measuring the nocturnal drainage flow in a high-elevation, subalpine forest with complex terrain

USGS Publications Warehouse

Yi, C.; Monson, Russell K.; Zhai, Z.; Anderson, D.E.; Lamb, B.; Allwine, G.; Turnipseed, A.A.; Burns, Sean P.

2005-01-01

The nocturnal drainage flow of air causes significant uncertainty in ecosystem CO2, H2O, and energy budgets determined with the eddy covariance measurement approach. In this study, we examined the magnitude, nature, and dynamics of the nocturnal drainage flow in a subalpine forest ecosystem with complex terrain. We used an experimental approach involving four towers, each with vertical profiling of wind speed to measure the magnitude of drainage flows and dynamics in their occurrence. We developed an analytical drainage flow model, constrained with measurements of canopy structure and SF6 diffusion, to help us interpret the tower profile results. Model predictions were in good agreement with observed profiles of wind speed, leaf area density, and wind drag coefficient. Using theory, we showed that this one-dimensional model is reduced to the widely used exponential wind profile model under conditions where vertical leaf area density and drag coefficient are uniformly distributed. We used the model for stability analysis, which predicted the presence of a very stable layer near the height of maximum leaf area density. This stable layer acts as a flow impediment, minimizing vertical dispersion between the subcanopy air space and the atmosphere above the canopy. The prediction is consistent with the results of SF6 diffusion observations that showed minimal vertical dispersion of nighttime, subcanopy drainage flows. The stable within-canopy air layer coincided with the height of maximum wake-to-shear production ratio. We concluded that nighttime drainage flows are restricted to a relatively shallow layer of air beneath the canopy, with little vertical mixing across a relatively long horizontal fetch. Insight into the horizontal and vertical structure of the drainage flow is crucial for understanding the magnitude and dynamics of the mean advective CO2 flux that becomes significant during stable nighttime conditions and are typically missed during measurement of the turbulent CO2 flux. The model and interpretation provided in this study should lead to research strategies for the measurement of these advective fluxes and their inclusion in the overall mass balance for CO2 at this site with complex terrain. Copyright 2005 by the American Geophysical Union.

Modeling and measuring the nocturnal drainage flow in a high-elevation, subalpine forest with complex terrain

NASA Astrophysics Data System (ADS)

Yi, Chuixiang; Monson, Russell K.; Zhai, Zhiqiang; Anderson, Dean E.; Lamb, Brian; Allwine, Gene; Turnipseed, Andrew A.; Burns, Sean P.

2005-11-01

The nocturnal drainage flow of air causes significant uncertainty in ecosystem CO2, H2O, and energy budgets determined with the eddy covariance measurement approach. In this study, we examined the magnitude, nature, and dynamics of the nocturnal drainage flow in a subalpine forest ecosystem with complex terrain. We used an experimental approach involving four towers, each with vertical profiling of wind speed to measure the magnitude of drainage flows and dynamics in their occurrence. We developed an analytical drainage flow model, constrained with measurements of canopy structure and SF6 diffusion, to help us interpret the tower profile results. Model predictions were in good agreement with observed profiles of wind speed, leaf area density, and wind drag coefficient. Using theory, we showed that this one-dimensional model is reduced to the widely used exponential wind profile model under conditions where vertical leaf area density and drag coefficient are uniformly distributed. We used the model for stability analysis, which predicted the presence of a very stable layer near the height of maximum leaf area density. This stable layer acts as a flow impediment, minimizing vertical dispersion between the subcanopy air space and the atmosphere above the canopy. The prediction is consistent with the results of SF6 diffusion observations that showed minimal vertical dispersion of nighttime, subcanopy drainage flows. The stable within-canopy air layer coincided with the height of maximum wake-to-shear production ratio. We concluded that nighttime drainage flows are restricted to a relatively shallow layer of air beneath the canopy, with little vertical mixing across a relatively long horizontal fetch. Insight into the horizontal and vertical structure of the drainage flow is crucial for understanding the magnitude and dynamics of the mean advective CO2 flux that becomes significant during stable nighttime conditions and are typically missed during measurement of the turbulent CO2 flux. The model and interpretation provided in this study should lead to research strategies for the measurement of these advective fluxes and their inclusion in the overall mass balance for CO2 at this site with complex terrain.

Reequilibration of fluid inclusions in low-temperature calcium-carbonate cement

NASA Astrophysics Data System (ADS)

Goldstein, Robert H.

1986-09-01

Calcium-carbonate cements precipitated in low-temperature, near-surface, vadose environments contain fluid inclusions of variable vapor-to-liquid ratios that yield variable homogenization temperatures. Cements precipitated in low-temperature, phreatic environments contain one-phase, all-liquid fluid inclusions. Neomorphism of unstable calcium-carbonate phases may cause reequilibration of fluid inclusions. Stable calcium-carbonate cements of low-temperature origin, which have been deeply buried, contain fluid inclusions of variable homogenization temperature and variable salt composition. Most inclusion fluids are not representative of the fluids present during cement growth and are more indicative of burial pore fluids. Therefore, low-temperature fluid inclusions probably reequilibrate with burial fluids during progressive burial. Reequilibration is likely caused by high internal pressures in inclusions which result in hydrofracturing. The resulting fluid-inclusion population could contain a nearly complete record of burial fluids in which a particular rock has been bathed. *Present address: Department of Geology, University of Kansas, Lawrence, Kansas 66045

Host-guest complexes of 2-hydroxypropyl-β-cyclodextrin/β-cyclodextrin and nifedipine: 1H NMR, molecular modeling, and dissolution studies

NASA Astrophysics Data System (ADS)

de Araújo, Márcia Valéria Gaspar; Vieira, João Victor Francisco; da Silva, Caroline W. P.; Barison, Andersson; Andrade, George Ricardo Santana; da Costa, Nivan Bezerra; Barboza, Fernanda Malaquias; Nadal, Jessica Mendes; Novatski, Andressa; Farago, Paulo Vitor; Zawadzki, Sônia Faria

2017-12-01

Nifedipine (NIF) is a hydrophobic drug widely used for treating cardiovascular diseases. This calcium channel blocker can present a higher apparent solubility by its inclusion into different cyclodextrins (CDs) as host-guest complexes. This paper focused on the structural investigation and dissolution behavior of inclusion complexes prepared with 2-hydroxypropyl-β-cyclodextrin (HPβCD) or β-cyclodextrin (βCD) and NIF. Drug amorphization was observed for HPβCD/NIF and βCD/NIF inclusion complexes by X-ray diffractometry (XRD). The sharp endothermic peak of NIF was not observed for these both host-guest complexes by differential scanning calorimetry (DSC). These results of XRD and DSC provide evidences of complexation between drug and the investigated CDs. 1H and saturation transfer difference nuclear magnetic resonance studies revealed the enhancement in the signal at 2.27 ppm for HPβCD/NIF and βCD/NIF inclusion complexes that corresponded to the methyl groups of NIF from the non-aromatic ring. This result suggested that non-aromatic ring of NIF was inserted into HPβCD and βCD cavities. Considering the mathematical simulations, it was observed that the inclusion process can occur in the both NH-in or NH-out forms. However, since it was used aqueous medium, it is possible to indicate that the obtained host-guest complexes HPβCD/NIF and βCD/NIF are in NH-in form which corresponded to the previous results obtained by 1H NMR experiments. Dissolution assays demonstrated that NIF inclusion complexes improved the drug release nevertheless without changing its biexponential release behavior. These host-guest complexes can be further used as feasible NIF carriers in solid dosage forms.

Formation Mechanism of Oxide-Sulfide Complex Inclusions in High-Sulfur-Containing Steel Melts

NASA Astrophysics Data System (ADS)

Shin, Jae Hong; Park, Joo Hyun

2018-02-01

The [S] content in resulfurized steel is controlled in the range of 200 to 800 ppm to ensure good machinability and workability. It is well known that "MgAl2O4(spinel)+CaS" complex inclusions are formed in molten steel during the ladle refining process, and these cause nozzle clogging during continuous casting. Thus, in the present study, the "Refractory-Slag-Metal-Inclusions (ReSMI)" multiphase reaction model was employed in conjunction with experiments to investigate the influence of slag composition and [S] content in the steel on the formation of oxide-sulfide complex inclusions. The critical [S] and [Al] contents necessary for the precipitation of CaS in the CaO-Al2O3-MgO-SiO2 (CAMS) oxide inclusions were predicted from the composition of the liquid inclusions, as observed by scanning electron microscopy-electron dispersive spectrometry (SEM-EDS) and calculated using the ReSMI multiphase reaction model. The critical [S] content increases with increasing content of SiO2 in the slag at a given [Al] content. Formation mechanisms for spinel+CaS and spinel+MnS complex inclusions were also proposed.

Study on the inclusion complex between β-cyclodextrin derivatives and flurbiprofen by spectrofluorometric

NASA Astrophysics Data System (ADS)

Miao, Jiabing; Guo, Zhaohua; Wang, Yongwang; Chen, Dong; Li, Yifan; Zhang, Feng

2017-08-01

The inclusion behavior between β-cyclodextrin derivatives (β-CDs) and flurbiprofen had been studied by fluorescence spectrophotometry. The effects of type and concentration of β-CDs; ionic strength; pH as well as temperature on inclusion behavior were investigated. And then the thermodynamic parameters ΔH/ΔS and ΔG of the inclusion complex of flurbiprofen and HP-β-CD were calculated, the driving force of the inclusion reaction had been also certified. The experimental results indicate, the fluorescence intensity (F) of flurbiprofen increases with the raising of β-CDs concentration, among the studied types of β-cyclodextrin derivatives, hydroxypropy l-β-cyclodextrin (HP-β-CD) has the most obvious enhancement, namely HP-β-CD has the strongest ability to complex with flurbiprofen. Plot of 1/ (F-F0) against 1/ [β-CD] yields a straight line, indicating 1:1 stoichiometric complex formed between β-CDs and flurbiprofen. Inclusion constant is enhanced with the increase in ionic strength of solution, whereas followes an opposite tendency with the rise of pH value. In the inclusive process, under normal temperature ΔG<0, it illustrates that this process is spontaneous, and the driving force is the change of enthalpy.

Starch-lipid complexes: Interesting material and applications from amylose-fatty acid salt inclusion complexes

USDA-ARS?s Scientific Manuscript database

Aqueous slurries of high amylose starch can be steam jet cooked and blended with aqueous solutions of fatty acid salts to generate materials that contain inclusion complexes between amylose and the fatty acid salt. These complexes are simply prepared on large scale using commercially available steam...

Cyclodextrin inclusion complex formation and solid-state characterization of the natural antioxidants alpha-tocopherol and quercetin.

PubMed

Koontz, John L; Marcy, Joseph E; O'Keefe, Sean F; Duncan, Susan E

2009-02-25

Cyclodextrin (CD) complexation procedures are relatively simple processes, but these techniques often require very specific conditions for each individual guest molecule. Variations of the coprecipitation from aqueous solution technique were optimized for the CD complexation of the natural antioxidants alpha-tocopherol and quercetin. Solid inclusion complex products of alpha-tocopherol/beta-CD and quercetin/gamma-CD had molar ratios of 1.7:1, which were equivalent to 18.1% (w/w) alpha-tocopherol and 13.0% (w/w) quercetin. The molar reactant ratios of CD/antioxidant were optimized at 8:1 to improve the yield of complexation. The product yields of alpha-tocopherol/beta-CD and quercetin/gamma-CD complexes from their individual reactants were calculated as 24 and 21% (w/w), respectively. ATR/FT-IR, 13C CP/MAS NMR, TGA, and DSC provided evidence of antioxidant interaction with CD at the molecular level, which indicated true CD inclusion complexation in the solid state. Natural antioxidant/CD inclusion complexes may serve as novel additives in controlled-release active packaging to extend the oxidative stability of foods.

Acquired Severe Disabilities and Complex Health Care Needs: Access to Inclusive Education

ERIC Educational Resources Information Center

Ballard, Sarah L.; Dymond, Stacy K.

2016-01-01

This case study examined one high school student's access to inclusive education and experiences in an inclusive English class after he acquired severe disabilities and complex health care needs from a nontraumatic brain injury. Multiple sources of data (i.e., interviews, field notes, and documents) were collected and analyzed to formulate…

In-vitro dissolution rate and molecular docking studies of cabergoline drug with β-cyclodextrin

NASA Astrophysics Data System (ADS)

Shanmuga priya, Arumugam; Balakrishnan, Suganya bharathi; Veerakanellore, Giri Babu; Stalin, Thambusamy

2018-05-01

The physicochemical properties and dissolution profile of cabergoline drug (CAB) with β-cyclodextrin (β-CD) inclusion complex were investigated by the UV spectroscopy. The inclusion complex has used to calculate the stability constant and gives the stoichiometry molar ratio is 1:1 between CAB and β-CD. The phase solubility diagram and the aqueous solubility of CAB (60%) was found to be enhanced by β-CD. In addition, the phase solubility profile of CAB with β-CD was classified as AL-type. Binary systems of CAB with β-CD were prepared by Physical mixture, Kneading and solvent evaporation methods. The solid-state properties of the inclusion complex were characterized by Fourier transformation-infrared spectroscopy, Differential scanning calorimetry, Powder X-ray diffractometric patterns and Scanning electron microscopic techniques. Theoretically, β-CD and CAB inclusion complex obtained by molecular docking studies, it is in good correlation with the results obtained through experimental methods using the Schrödinger software program. In-vitro dissolution profiles of the inclusion complexes were carried out and obvious increase in dissolution rate was observed when compared with pure CAB drug and the complexes.

[Effect of β-cyclodextrin inclusion complex on transport of major components of Xiangfu Siwu decoction essential oil in Caco-2 cell monolayer model].

PubMed

Xi, Jun-zuan; Qian, Da-wei; Duan, Jin-ao; Liu, Pei; Zhu, Yue; Zhu, Zhen-hua; Zhang, Li

2015-08-01

Although the essential oil of Xiangfu Siwu decoction (XFSWD) has strong pharmacological activity, its special physical and chemical properties restrict the clinical application and curative effect. In this paper, Xiangfu Siwu decoction essential oil (XFS-WO) was prepared by forming inclusion complex with β-cyclodextrin (β-CD). The present study is to investigate the effect of β-CD inclusion complex on the transport of major components of XFSWO using Caco-2 cell monolayer model, thus to research the effect of this formation on the absorption of drugs with low solubility and high permeability, which belong to class 2 in biopharmaceutics classification system. A sensitive and rapid UPLC-MS/MS method was developed for simultaneous quantification of senkyunolide A, 3-n-butylphthalide, Z-ligustilide, dehydrocostus lactone and α-cyperone, which are active compounds in XFSWO. The transport parameters were analyzed and compared in free oil and its β-CD inclusion complex. The result revealed that the formation of XFSWO/β-CD inclusion complex has significantly increased the transportation and absorption of major active ingredients than free oil. Accordingly, it can be speculated that cyclodextrin inclusion complex can improve bioavailability of poorly water-soluble drugs. Above all these mentioned researches, it provided foundation and basis for physiological disposition and pharmaceutical study of XFSWD.

Stable isotope study of fluid inclusions in fluorite from Idaho: implications for continental climates during the Eocene

USGS Publications Warehouse

Seal, R.R.; Rye, R.O.

1993-01-01

Isotopic studies of fluid inclusions from meteoric water-dominated epithermal ore deposits offer a unique opportunity to study paleoclimates because the fluids can provide direct samples of ancient waters. Fluorite-hosted fluid inclusions from the Eocene (51-50 Ma) epithermal deposits of the Bayhorse mining district, have low salinities and low to moderate homogenization temperatures indicating meteoric origins for the fluids. Oxygen and hydrogen isotope data on inclusion fluids are almost identical to those of modern meteoric waters in the area. The equivalence of the isotope composition of the Eocene inclusion fluids and modern meteoric waters indicates that the Eocene climatic conditions were similar to those today. -from Authors

Study of β-cyclodextrin inclusion complexes with volatile molecules geraniol and α-terpineol enantiomers in solid state and in solution

NASA Astrophysics Data System (ADS)

Ceborska, Magdalena; Szwed, Kamila; Asztemborska, Monika; Wszelaka-Rylik, Małgorzata; Kicińska, Ewa; Suwińska, Kinga

2015-11-01

Geraniol and α-terpineol are insoluble in water volatile compounds. α-Terpineol is a potentially important agent for medical applications. Formation of molecular complexes with β-cyclodextrin would lead to the increase of water solubility and bioavailability. β-Cyclodextrin forms 2:2 inclusion complexes with both enantiomers of α-terpineol and their precursor geraniol. Solid state complexes are thoroughly characterized by single X-ray crystallography and their stability over vast range of temperatures is proven by TG analysis. Intermolecular host-guest, host-host and guest-guest interactions give good insight into the nature of formed inclusion complexes. Stability constants of the complexes in solution are determined by HPLC.

Impact of Inclusion of Varying Percentages of Repeaters on Equating

ERIC Educational Resources Information Center

Rogers, W. Todd; Radwan, Nizam

2015-01-01

Restricted equating samples are often used to equate test results. Previously eligible students may be excluded because this group of students is not stable from year to year and their inclusion may bias the results. The present study evaluated the impact of including previously eligible students in the equating samples, where the percentage of…

Starch-lipid inclusion complexes for aerogel formation

USDA-ARS?s Scientific Manuscript database

Recently we reported that aqueous slurries of starch can be excess steam jet-cooked and blended with aqueous solutions of fatty acid salts to produce inclusion complexes between amylose and the fatty acid salt. These complexes can be simply prepared on large scale using commercially available steam ...

Characteristic effects of substituent and external pressure on group-inclusion complexation with p-sulfonatocalix[8]arene and γ-cyclodextrin

NASA Astrophysics Data System (ADS)

Miyazono, Keitaro; Hanaya, Tadashi; Sueishi, Yoshimi

2014-07-01

By synthesizing unique nitroxide probes (α-substituted phenyl-2,4,6-trimethoxybenzyl(t-butyl)nitroxide), we have shown that p-sulfonatocalix[8]arene (Calix-S8) and γ-cyclodextin (γ-CD) form electron spin resonance spectroscopically separable group-inclusion complexes (α-substituted phenyl-in (R-in) and t-butyl-in complexes) and determined the group-inclusion constants of Calix-S8 and γ-CD. Using nitroxide probes, we have examined the effects of substituent and external pressure on group-inclusion complexation with Calix-S8 and γ-CD. Experiments on pressure dependence enabled us to calculate the reaction volume (Δ V) for R-in and t-butyl-in complex formations. Δ V for group-in complexation with Calix-S8 had negative values. In contrast, Δ V values for γ-CD showed positive values, which is responsible for the repelled water molecules in the CD cavity. The characteristic pressure effects on group-in complexation suggest that group recognition by γ-CD is sensitive when compared with that by Calix-S8.

Use of cyclodextrins as a cosmetic delivery system for fragrance materials: linalool and benzyl acetate.

PubMed

Numanoğlu, Ulya; Sen, Tangül; Tarimci, Nilüfer; Kartal, Murat; Koo, Otilia M Y; Onyüksel, Hayat

2007-10-19

The aim of this study was to increase the stability and water solubility of fragrance materials, to provide controlled release of these compounds, and to convert these substances from liquid to powder form by preparing their inclusion complexes with cyclodextrins (CDs). For this purpose, linalool and benzyl acetate were chosen as the fragrance materials. The use of beta-cyclodextrin (beta CD) and 2-hydroxypropyl-beta-cyclodextrin (2-HP beta CD) for increasing the solubility of these 2 fragrance materials was studied. Linalool and benzyl acetate gave a B-type diagram with beta CD, whereas they gave an A(L)-type diagram with 2-HP beta CD. Therefore, complexes of fragrance materials with 2-HP beta CD at 1:1 and 1:2 molar ratios (guest:host) were prepared. The formation of inclusion complexes was confirmed using proton nuclear magnetic resonance ((1)H-NMR) spectroscopy and circular dichroism spectroscopy. The results of the solubility studies showed that preparing the inclusion complex with 2-HP beta CD at a 1:1 molar ratio increased the solubility of linalool 5.9-fold and that of benzyl acetate 4.2-fold, whereas the complexes at a 1:2 molar ratio increased the solubility 6.4- and 4.5-fold for linalool and benzyl acetate, respectively. The stability and in vitro release studies were performed on the gel formulations prepared using uncomplexed fragrance materials or inclusion complexes of fragrance materials at a 1:1 molar ratio. It was observed that the volatility of both fragrance materials was decreased by preparing the inclusion complexes with 2-HP beta CD. Also, in vitro release data indicated that controlled release of fragrances could be possible if inclusion complexes were prepared.

Increased water resistance of paper treated with amylose-fatty ammonium salt inclusion complexes

USDA-ARS?s Scientific Manuscript database

Amylose inclusion complexes were prepared from high amylose corn starch and the HCl salts of hexadecylamine and octadecylamine. Solutions of the complexes were applied to paper at concentrations of 2-4%. After the treated papers were dried, sodium hydroxide solution was applied to convert the adsorb...

Effect of spray drying on the properties of amylose-hexadecylammonium chloride inclusion complexes

USDA-ARS?s Scientific Manuscript database

Water soluble amylose-hexadecyl ammonium chloride complexes were prepared from high amylose corn starch and hexadecyl ammonium chloride by excess steam jet cooking. Amylose inclusion complexes were spray dried to determine the viability of spray drying as a production method. The variables tested in...

Crystallographic Orientation Relationships (CORs) between rutile inclusions and garnet hosts: towards using COR frequencies as a petrogenetic indicator

NASA Astrophysics Data System (ADS)

Griffiths, Thomas; Habler, Gerlinde; Schantl, Philip; Abart, Rainer

2017-04-01

Crystallographic orientation relationships (CORs) between crystalline inclusions and their hosts are commonly used to support particular inclusion origins, but often interpretations are based on a small fraction of all inclusions in a system. The electron backscatter diffraction (EBSD) method allows collection of large COR datasets more quickly than other methods while maintaining high spatial resolution. Large datasets allow analysis of the relative frequencies of different CORs, and identification of 'statistical CORs', where certain limited degrees of freedom exist in the orientation relationship between two neighbour crystals (Griffiths et al. 2016). Statistical CORs exist in addition to completely fixed 'specific' CORs (previously the only type of COR considered). We present a comparison of three EBSD single point datasets (all N > 200 inclusions) of rutile inclusions in garnet hosts, covering three rock systems, each with a different geological history: 1) magmatic garnet in pegmatite from the Koralpe complex, Eastern Alps, formed at temperatures > 600°C and low pressures; 2) granulite facies garnet rims on ultra-high-pressure garnets from the Kimi complex, Rhodope Massif; and 3) a Moldanubian granulite from the southeastern Bohemian Massif, equilibrated at peak conditions of 1050°C and 1.6 GPa. The present study is unique because all datasets have been analysed using the same catalogue of potential CORs, therefore relative frequencies and other COR properties can be meaningfully compared. In every dataset > 94% of the inclusions analysed exhibit one of the CORs tested for. Certain CORs are consistently among the most common in all datasets. However, the relative abundances of these common CORs show large variations between datasets (varying from 8 to 42 % relative abundance in one case). Other CORs are consistently uncommon but nonetheless present in every dataset. Lastly, there are some CORs that are common in one of the datasets and rare in the remainder. These patterns suggest competing influences on relative COR frequencies. Certain CORs seem consistently favourable, perhaps pointing to very stable low energy configurations, whereas some CORs are favoured in only one system, perhaps due to particulars of the formation mechanism, kinetics or conditions. Variations in COR frequencies between datasets seem to correlate with the conditions of host-inclusion system evolution. The two datasets from granulite-facies metamorphic samples show more similarities to each other than to the pegmatite dataset, and the sample inferred to have experienced the highest temperatures (Moldanubian granulite) shows the lowest diversity of CORs, low frequencies of statistical CORs and the highest frequency of specific CORs. These results provide evidence that petrological information is being encoded in COR distributions. They make a strong case for further studies of the factors influencing COR development and for measurements of COR distributions in other systems and between different phases. Griffiths, T.A., Habler, G., Abart, R. (2016): Crystallographic orientation relationships in host-inclusion systems: New insights from large EBSD data sets. Amer. Miner., 101, 690-705.

Development of carvedilol-cyclodextrin inclusion complexes using fluid-bed granulation: a novel solid-state complexation alternative with technological advantages.

PubMed

Alonso, Ellen C P; Riccomini, Karina; Silva, Luis Antônio D; Galter, Daniela; Lima, Eliana M; Durig, Thomas; Taveira, Stephania F; Martins, Felipe Terra; Cunha-Filho, Marcílio S S; Marreto, Ricardo N

2016-10-01

This study sought to evaluate the achievement of carvedilol (CARV) inclusion complexes with modified cyclodextrins (HPβCD and HPγCD) using fluid-bed granulation (FB). The solid complexes were produced using FB and spray drying (SD) and were characterised by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction, SEM, flowability and particle size analyses and in vitro dissolution. The DSC, FTIR and powder X-ray diffraction findings suggested successful CARV inclusion in the modified β- and γ-cyclodextrins, which was more evident in acidic media. The CARV dissolution rate was ~7-fold higher for complexes with both cyclodextrins prepared using SD than for raw CARV. Complexes prepared with HPβCD using FB also resulted in a significant improvement in dissolution rate (~5-fold) and presented superior flowability and larger particle size. The findings suggested that FB is the best alternative for large-scale production of solid dosage forms containing CARV. Additionally, the results suggest that HPγCD could be considered as another option for CARV complexation because of its excellent performance in inclusion complex formation in the solid state. © 2016 Royal Pharmaceutical Society.

Thermodynamic study on the effects of β-cyclodextrin inclusion with berberine

NASA Astrophysics Data System (ADS)

Yu, Jun-Sheng; Wei, Fang-Di; Gao, Wei; Zhao, Chang-Chun

2002-01-01

The fluorescence enhancement of berberine (Berb) as a result of complex with β-cyclodextrin (β-CD) is investigated. The association constants of α-CD and β-CD with Berb are 60 and 137 M -1 at 20 °C in pH 7.20 aqueous solution. Effects of temperature on the forming inclusion complexes of β-CD with Berb have been examined through using fluorescence titration. Enthalpy and entropy values calculated from fluorescence data are -33.7·kJ mol -1 and 74.3 J·mol -1·K -1, respectively. It was found that the dielectric constant of β-CD cavity is about 24 in a rough analogy with absolute alcohol. These results suggest that the extrusion of 'high energy water' molecules from the cavity of β-CD and hydrophobic interaction upon the inclusion complex formation are the main forces of the inclusion reaction. Effect of pH on the association of β-CD with Berb was also studied. Mechanism of the inclusion of β-CD with Berb is further studied by absorption and NMR measurements. Results show that β-CD forms a 1:1 inclusion complex with Berb.

Inclusion of Paracetamol into β-cyclodextrin nanocavities in solution and in the solid state

NASA Astrophysics Data System (ADS)

El-Kemary, Maged; Sobhy, Saffaa; El-Daly, Samy; Abdel-Shafi, Ayman

2011-09-01

We report on steady-state UV-visible absorption and emission characteristics of Paracetamol, drug used as antipyretic agent, in water and within cyclodextrins (CDs): β-CD, 2-hydroxypropyl- β-CD (HP- β-CD) and 2,6-dimethyl- β-CD (Me- β-CD). The results reveal that Paracetamol forms a 1:1 inclusion complex with CD. Upon encapsulation, the emission intensity enhances, indicating a confinement effect of the nanocages on the photophysical behavior of the drug. Due to its methyl groups, the Me- β-CD shows the largest effect for the drug. The observed binding constant showing the following trend: Me- β-CD > HP- β-CD > β-CD. The less complexing effectiveness of HP- β-CD is due to the steric effect of the hydroxypropyl-substituents, which can hamper the inclusion of the guest molecules. The solid state inclusion complex was prepared by co-precipitation method and its characterization was investigated by Fourier transform infrared spectroscopy, 1H NMR and X-ray diffractometry. These approaches indicated that Paracetamol was able to form an inclusion complex with CDs, and the inclusion compounds exhibited different spectroscopic features and properties from Paracetamol.

Piroxicam/2-hydroxypropyl-beta-cyclodextrin inclusion complex prepared by a new fluid-bed coating technique.

PubMed

Zhang, Xingwang; Wu, Danni; Lai, Jie; Lu, Yi; Yin, Zongning; Wu, Wei

2009-02-01

This work was aimed at investigating the feasibility of fluid-bed coating as a new method to prepare cyclodextrin inclusion complex. The inclusion complex of the model drug piroxicam (PIX) and 2-hydroxypropyl-beta-cyclodextrin (HPCD) in aqueous ethanol solution was sprayed and deposited onto the surface of the pellet substrate upon removal of the solvent. The coating process was fluent with high coating efficiency. Scanning electron microscopy revealed a coarse pellet surface, and a loosely packed coating structure. Significantly enhanced dissolution, over 90% at 5 min, was observed at stoichiometric PIX/HPCD molar ratio (1/1) and at a ratio with excessive HPCD (1/2). Differential scanning calorimetry and powder X-ray diffractometry confirmed absence of crystallinity of PIX at PIX/HPCD molar ratio of 1/1 and 1/2. Fourier transform-infrared spectrometry and Raman spectrometry revealed interaction between PIX and HPCD adding evidence on inclusion of PIX moieties into HPCD cavities. Solid-state (13)C NMR spectrometry indicated possible inclusion of PIX through the pyridine ring. It is concluded that fluid-bed coating has potential to be used as a new technique to prepare cyclodextrin inclusion complex.

Preparation, characterization and in vitro evaluation of a new nucleotide analogue prodrug cyclodextrin inclusion complexes.

PubMed

Diab, Roudayna; Jordheim, Lars P; Degobert, Ghania; Peyrottes, Suzanne; Périgaud, Christian; Dumontet, Charles; Fessi, Hatem

2009-01-01

Bis(tbutyl-S-acyl-2-thioethyl)-cytidine monophosophate is a new cytotoxic mononucleotide prodrug which have been developed to reverse the cellular resistance to nucleoside analogues. Unfortunately, its in vivo utilisation was hampered by its poor water solubility, raising the need of a molecular vector capable to mask its physicochemical characteristics although without affecting its cytotoxic activity. Hydroxypropyl-beta-cyclodextrin was used to prepare the prodrug inclusion complexes, allowing it to be solubilized in water and hence to be used for in vitro and in vivo experiments. A molar ratio of the cyclodextrin: prodrug of 3 was sufficient to obtain complete solubilization of the prodrug. The inclusion complex was characterized by differential scanning calorimetry, which revealed the disappearance of the melting peak of the prodrug suggesting the formation of inclusion complex. Proton Nuclear Magnetic Resonance spectroscopy provided a definitive proof of the inclusion complex formation, which was evidenced by the large chemical shift displacements observed for protons located in the interior of the hydrophobic cyclodextrin cavity. The complex retained its cytotoxic activity as shown by in vitro cell survival assays on murine leukemia cells. These results provided a basis for potential therapeutic applications of co-formulation of this new nucleotide analogue with hydroxypropyl-beta-CD in cancer therapy.

[Preparation of coated tablets of glycyrrhetic acid-HP-beta-cyclodextrin tablets for colon-specific release].

PubMed

Cui, Qi-Hua; Cui, Jing-Hao; Zhang, Jin-Jin

2008-10-01

To prepare coated tablets of glycyrrhetinic acid and hydroxypropyl-beta-cyclodextrin (GTA-HP-beta-CYD) inclusion complex tablets for colon-specific release. In order to improve the solubility of GTA, the GTA-HP-beta-CYD inclusion complex was prepared by ultrasonic-lyophilization technique and its formation were characterized by X-ray powder diffraction profiles and infrared spectrometry. The effects of inclusion condition on the inclusion efficiency and stability coefficient of inclusion complex were investigated, respectively. After prepared GTA-HP-beta-CYD tablets by powder direct compression, the pH dependant polymer Eudragit III and/or mixed with Eudragit II were used for further coating materials in fluid-bed coater. The influences of coating weight on the GTA release in different pH conditions were evaluated to establish the method for prepering colon specific delivery tablets with pulsed release properties. The formation of inclusion complexes were proved by X-ray powder diffraction profile and phase solubility curve. The effect of pH value of solvent was played critical role on the preparation of GTA- HP-beta-CYD inclusion complex. And the inclusion efficiency of GTA was 9. 3% and the solubility was increased to 54. 6 times at optimized method. The Eudragit III coated GTA- HP-beta-CYD tablets with coating weight 10% and 16% were showed pH dependant colon specific release profiles with slow release rate. The release profile of tablets coated with the mixture of Eudragit II and Eudragit III (1:2) were indicated typical pH dependant colon specific and pulsed release properties while the coating weight was 17%. The preliminary method for preparation of colon specific release tablets containing glycyrrhetinic acid with improved solubility was established for further in vivo therapeutic experiment.

Formation of β-cyclodextrin inclusion enhances the stability and aqueous solubility of natural borneol.

PubMed

Su, Jianyu; Chen, Jianping; Li, Lin; Li, Bing; Shi, Lei; Chen, Ling; Xu, Zhenbo

2012-06-01

The aims of this study were to optimize the preparation conditions of natural borneol/β-cyclodextrin (NB/β-CD) inclusion complex by ultrasound method, and to investigate its improvement of stability and solubility. The complex was characterized by different various spectroscopic techniques including Fourier transform infrared spectroscopy, X-ray diffractometry, and differential scanning calorimetry. The results demonstrate that NB could be efficiently loaded into β-CD to form an inclusion complex by ultrasound method at a molar ratio of 1: 1and mass ratio of 1: 6. The complex exhibited different physicochemical characteristics from that of free NB. Typically, formation of β-CD inclusion significantly enhanced the stability and aqueous solubility of NB. Natural borneol (NB) has the potential to be widely used in the fields of medical and functional food, due to its specificity. However, the disadvantages of unstability in the preparation and storage process due to its easy sublimation and the low water solubility limit its application. This research provides an effective way to improve the solubility and stability of NB by preparing NB/β-CD inclusion complex. Furthermore, theoretical basis is also provided for the application development of NB. © 2012 Institute of Food Technologists®

β-Cyclodextrin inclusion complex: preparation, characterization, and its aspirin release in vitro

NASA Astrophysics Data System (ADS)

Zhou, Hui-Yun; Jiang, Ling-Juan; Zhang, Yan-Ping; Li, Jun-Bo

2012-09-01

In this work, the optimal clathration condition was investigated for the preparation of aspirin-β-cyclodextrin (Asp-β-CD) inclusion complex using design of experiment (DOE) methodology. A 3-level, 3-factor Box-Behnken design with a total of 17 experimental runs was used. The Asp-β-CD inclusion complex was prepared by saturated solution method. The influence on the embedding rate was investigated, including molar ratio of β-CD to Asp, clathration temperature and clathration time, and the optimum values of such three test variables were found to be 0.82, 49°C and 2.0 h, respectively. The embedding rate could be up to 61.19%. The formation of the bonding between -COOH group of Asp and O-H group of β-CD might play an important role in the process of clathration according to FT-IR spectra. Release kinetics of Asp from inclusion complex was studied for the evaluation of drug release mechanism and diffusion coefficients. The results showed that the drug release from matrix occurred through Fickian diffusion mechanism. The cumulative release of Asp reached only 40% over 24 h, so the inclusion complex could potentially be applied as a long-acting delivery system.

Cyclodextrin based ternary system of modafinil: Effect of trimethyl chitosan and polyvinylpyrrolidone as complexing agents.

PubMed

Patel, Parth; Agrawal, Y K; Sarvaiya, Jayrajsinh

2016-03-01

Modafinil is an approved drug for the treatment of narcolepsy and have a strong market presence in many countries. The drug is widely consumed for off-label uses and currently listed as a restricted drug. Modafinil has very low water solubility. To enhance the aqueous solubility of modafinil by the formation of a ternary complex with Hydroxypropyl-β-cyclodextrin and two hydrophilic polymers was the main objective of the present study. Pyrrolidone (PVP K30) and a water soluble chitosan derivative, trimethyl chitosan (TMC) were studied by solution state and solid state characterization methods for their discriminatory efficiency in solubility enhancement of modafinil. Phase solubility study depicted the highest complexation efficiency (2.22) of cyclodextrin derivative in the presence of TMC compared to the same in the presence of PVP K30 (0.08) and in the absence of any polymer (0.92). FT-IR analysis of binary and ternary complex expressed comparable contribution of both polymers in formation of inclusion complex. The thermal behaviour of binary and ternary complex, involving individual polymers disclosed the influence of TMC on polymorphism of the drug. DSC study revealed efficiency of TMC to prevent conversion of metastable polymorphic form to stable polymorphic form. Ternary complex, involving TMC enhanced water solubility of the drug 1.5 times more compared to the binary complex of the drug whereas PVP K30 reduced the Solubility. Copyright © 2015 Elsevier B.V. All rights reserved.

Amylose-dicarboxylic acid inclusion complexes: Characterization and comparison to monocarboxylic acid complexes

USDA-ARS?s Scientific Manuscript database

One of the main components in starch, amylose is an essentially linear polymer composed of glucose connected through alpha-1,4-bonds. Amylose is well known to form helical inclusion complexes with various types of ligands such as iodine, medium and long chain fatty acids, alcohols, lactones, and fl...

Solving the Problem of Bending of Multiply Connected Plates with Elastic Inclusions

NASA Astrophysics Data System (ADS)

Kaloerov, S. A.; Koshkin, A. A.

2017-11-01

This paper describes a method for determining the strain state of a thin anisotropic plate with elastic arbitrarily arranged elliptical inclusions. Complex potentials are used to reduce the problem to determining functions of generalized complex variables, which, in turn, comes down to an overdetermined system of linear algebraic equations, solved by singular expansions. This paper presents the results of numerical calculations that helped establish the influence of rigidity of elastic inclusions, distances between inclusions, and their geometric characteristics on the bending moments occurring in the plate. It is found that the specific properties of distribution of moments near the apexes of linear elastic inclusions, characterized by moment intensity coefficients, occur only in the case of sufficiently rigid and elastic inclusions.

26 CFR 1.662(a)-1 - Inclusion of amounts in gross income of beneficiaries of estates and complex trusts; general.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 26 Internal Revenue 8 2012-04-01 2012-04-01 false Inclusion of amounts in gross income of beneficiaries of estates and complex trusts; general. 1.662(a)-1 Section 1.662(a)-1 Internal Revenue INTERNAL...) Estates and Trusts Which May Accumulate Income Or Which Distribute Corpus § 1.662(a)-1 Inclusion of...

26 CFR 1.662(a)-1 - Inclusion of amounts in gross income of beneficiaries of estates and complex trusts; general.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 26 Internal Revenue 8 2013-04-01 2013-04-01 false Inclusion of amounts in gross income of beneficiaries of estates and complex trusts; general. 1.662(a)-1 Section 1.662(a)-1 Internal Revenue INTERNAL...) Estates and Trusts Which May Accumulate Income Or Which Distribute Corpus § 1.662(a)-1 Inclusion of...

26 CFR 1.662(a)-1 - Inclusion of amounts in gross income of beneficiaries of estates and complex trusts; general.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 26 Internal Revenue 8 2014-04-01 2014-04-01 false Inclusion of amounts in gross income of beneficiaries of estates and complex trusts; general. 1.662(a)-1 Section 1.662(a)-1 Internal Revenue INTERNAL...) Estates and Trusts Which May Accumulate Income Or Which Distribute Corpus § 1.662(a)-1 Inclusion of...

26 CFR 1.662(a)-1 - Inclusion of amounts in gross income of beneficiaries of estates and complex trusts; general.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 26 Internal Revenue 8 2011-04-01 2011-04-01 false Inclusion of amounts in gross income of beneficiaries of estates and complex trusts; general. 1.662(a)-1 Section 1.662(a)-1 Internal Revenue INTERNAL...) Estates and Trusts Which May Accumulate Income Or Which Distribute Corpus § 1.662(a)-1 Inclusion of...

Relationship between crystallographic structure of the Ti{sub 2}O{sub 3}/MnS complex inclusion and microstructure in the heat-affected zone (HAZ) in steel processed by oxide metallurgy route and impact toughness

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

Xiong, Zhihui; Liu, Shilong; Wang, Xuemin, E-mail: wxm@mater.ustb.edu.cn

2015-08-15

A new method based on electron back scattered diffraction (EBSD) is proposed to determine the structure of titanium oxide/MnS complex inclusion which induced the formation of intragranular acicular ferrite (IAF) in heat-affected zone (HAZ) in steel processed by oxide metallurgy route. It was found that the complex inclusion was Ti{sub 2}O{sub 3}/MnS, the orientation relationship between Ti{sub 2}O{sub 3} and MnS was also examined, and the crystallographic orientation relationship among IAF, Ti{sub 2}O{sub 3}/MnS complex inclusion, austenite, bainite formed at lower temperature is researched systematically. It was observed that MnS precipitated on Ti{sub 2}O{sub 3} at specific habit plane andmore » direction and MnS had a specific orientation relationship ((0001) Ti{sub 2}O{sub 3}//(111) MnS), <10–10> Ti{sub 2}O{sub 3}//<110> MnS) with respect to Ti{sub 2}O{sub 3}. Intragranular acicular ferrite (IAF) nucleated on MnS part of the Ti{sub 2}O{sub 3}/MnS complex inclusion had no specific orientation relationship with MnS. IAF and the surrounding bainite had different Bain groups, so that there was an increase in high angle boundaries, which was beneficial for the toughness of HAZ. - Highlights: • The inclusion of TiO{sub x}/MnS that induced IAF formation is identified to be Ti{sub 2}O{sub 3}/MnS. • The inclusion is identified based on electron back scattered diffraction (EBSD). • MnS and Ti{sub 2}O{sub 3} had specific orientation relationship of Ti{sub 2}O{sub 3}/MnS complex inclusion. • The IAFs formed on the same inclusion tend to be in one Bain group. • IAF and the surrounding bainite tend to be in different Bain groups.« less

Effect of γ-Cyclodextrin Inclusion Complex on the Absorption of R-α-Lipoic Acid in Rats

PubMed Central

Uchida, Ryota; Iwamoto, Kosuke; Nagayama, Suetada; Miyajima, Atsushi; Okamoto, Hinako; Ikuta, Naoko; Fukumi, Hiroshi; Terao, Keiji; Hirota, Takashi

2015-01-01

R-α-lipoic acid (RLA) is an endogenous organic acid, and works as a cofactor for mitochondrial enzymes and as a kind of antioxidant. Inclusion complexes of RLA with α-, β- or γ-cyclodextrins (CD) were prepared and orally administered as a suspension to rats. Among them, RLA/γ-CD showed the highest plasma exposure, and its area under the plasma concentration-time curve (AUC) of RLA was 2.2 times higher than that after oral administration of non-inclusion RLA. On the other hand, the AUC after oral administration of non-inclusion RLA and RLA/γ-CD to pylorus-ligated rats did not differ. However, the AUC after intraduodenal administration of RLA/γ-CD was 5.1 times higher than that of non-inclusion RLA, and was almost comparable to the AUC after intraduodenal administration of RLA-Na solution. Furthermore, the AUC after intraduodenal administration of RLA/γ-CD was not affected by biliary ligation or co-administration of an amylase inhibitor. These findings demonstrated that RLA was absorbed from the small intestine effectively when orally administered as a γ-CD inclusion complex, which could be easily dissolved in the lumen of the intestine. In conclusion, γ-CD inclusion complex is an appropriate formulation for supplying RLA as a drug or nutritional supplement with respect to absorption. PMID:25946345

Solubility Enhancement of Steviol Glycosides and Characterization of Their Inclusion Complexes with Gamma-Cyclodextrin

PubMed Central

Upreti, Mani; Strassburger, Ken; Chen, You L.; Wu, Shaoxiong; Prakash, Indra

2011-01-01

Steviol glycosidesrebaudioside (reb) A, C and D have low aqueous solubilities. To improve their aqueous solubilities, inclusion complex of steviol glycosides, reb A, C and D and gamma cyclodextrin were prepared by freeze drying method and further characterized by means of differential scanning calorimetry, Fourier transform infrared spectroscopy and Raman spectroscopy. The effect of gamma cyclodextrin on chemical shifts of the steviol glycosides was also studied in proton NMR experiments as well as in solid state 13C CP/MAS NMR experiments. These results indicated that the steviol glycosides were clearly in inclusion complex formation with the gamma cyclodextrin which also results in solubility enhancement of these steviol glycosides. Phase solubility studies showed that amounts of soluble reb A, C and D increased with increasing amounts of gamma cyclodextrin indicating formation of 1:1 stoichiometric and higher order inclusion complexes. PMID:22174615

Inclusion Complexes of a New Family of Non-Ionic Amphiphilic Dendrocalix[4]arene and Poorly Water-Soluble Drugs Naproxen and Ibuprofen.

PubMed

Khan, Khalid; Badshah, Syed Lal; Ahmad, Nasir; Rashid, Haroon Ur; Mabkhot, Yahia

2017-05-11

The inclusion complexes of a new family of nonionic amphiphilic calix[4]arenes with the anti-inflammatory hydrophobic drugs naproxen (NAP) and ibuprofen (IBP) were investigated. The effects of the alkyl chain's length and the inner core of calix[4]arenes on the interaction of the two drugs with the calix[4]arenes were explored. The inclusion complexes of Amphiphiles 1a - c with NAP and IBP increased the solubility of these drugs in aqueous media. The interaction of 1a - c with the drugs in aqueous media was investigated through fluorescence, molecular modeling, and ¹H-NMR analysis. TEM studies further supported the formation of inclusion complexes. The length of lipophilic alkyl chains and the intrinsic cyclic nature of cailx[4]arene derivatives 1a - c were found to have a significant impact on the solubility of NAP and IBP in pure water.

Films prepared from poly(vinyl alcohol) and amylose-fatty acid salt inclusion complexes with increased surface hydrophobicity and high elongation

USDA-ARS?s Scientific Manuscript database

In this study, water-soluble amylose-inclusion complexes were prepared from high amylose corn starch and sodium salts of lauric, palmitic, and stearic acid by steam jet cooking. Cast films were prepared by combining the amylose complexes with poly(vinyl alcohol)(PVOH) solution at ratios varying from...

Contribution of Electrostatics to the Kinetics of Electron Transfer from NADH-Cytochrome b5 Reductase to Fe(III)-Cytochrome b5.

PubMed

Kollipara, Sireesha; Tatireddy, Shivakishore; Pathirathne, Thusitha; Rathnayake, Lasantha K; Northrup, Scott H

2016-08-25

Brownian dynamics (BD) simulations provide here a theoretical atomic-level treatment of the reduction of human ferric cytochrome b5 (cyt b5) by NADH-cytochrome b5 reductaste (cyt b5r) and several of its mutants. BD is used to calculate the second-order rate constant of electron transfer (ET) between the proteins for direct correlation with experiments. Interestingly, the inclusion of electrostatic forces dramatically increases the reaction rate of the native proteins despite the overall negative charge of both proteins. The role played by electrostatic charge distribution in stabilizing the ET complexes and the role of mutations of several amino acid residues in stabilizing or destabilizing the complexes are analyzed. The complex with the shortest ET reaction distance (d = 6.58 Å) from rigid body BD is further subjected to 1 ns of molecular dynamics (MD) in a periodic box of TIP3P water to produce a more stable complex allowed by flexibility and with a shorter average reaction distance d = 6.02 Å. We predict a docking model in which the following ion-ion interactions are dominant (cyt b5r/cyt b5): Lys162-Heme O1D/Lys163-Asp64/Arg91-Heme O1A/Lys125-Asp70.

26 CFR 1.662(a)-1 - Inclusion of amounts in gross income of beneficiaries of estates and complex trusts; general.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Inclusion of amounts in gross income of beneficiaries of estates and complex trusts; general. 1.662(a)-1 Section 1.662(a)-1 Internal Revenue INTERNAL... Trusts Which May Accumulate Income Or Which Distribute Corpus § 1.662(a)-1 Inclusion of amounts in gross...

Study to explore the mechanism to form inclusion complexes of β-cyclodextrin with vitamin molecules

PubMed Central

Saha, Subhadeep; Roy, Aditi; Roy, Kanak; Roy, Mahendra Nath

2016-01-01

Host–guest inclusion complexes of β-cyclodextrin with two vitamins viz., nicotinic acid and ascorbic acid in aqueous medium have been explored by reliable spectroscopic, physicochemical and calorimetric methods as stabilizer, carrier and regulatory releaser of the guest molecules. Job’s plots have been drawn by UV-visible spectroscopy to confirm the 1:1 stoichiometry of the host-guest assembly. Stereo-chemical nature of the inclusion complexes has been explained by 2D NMR spectroscopy. Surface tension and conductivity studies further support the inclusion process. Association constants for the vitamin-β-CD inclusion complexes have been calculated by UV-visible spectroscopy using both Benesi–Hildebrand method and non-linear programme, while the thermodynamic parameters have been estimated with the help of van’t Hoff equation. Isothermal titration calorimetric studies have been performed to determine the stoichiometry, association constant and thermodynamic parameters with high accuracy. The outcomes reveal that there is a drop in ΔSo, which is overcome by higher negative value of ΔHo, making the overall inclusion process thermodynamically favorable. The association constant is found to be higher for ascorbic acid than that for nicotinic acid, which has been explained on the basis of their molecular structures. PMID:27762346

Architecture of Amylose Supramolecules in Form of Inclusion Complexes by Phosphorylase-Catalyzed Enzymatic Polymerization

PubMed Central

Kadokawa, Jun-ichi

2013-01-01

This paper reviews the architecture of amylose supramolecules in form of inclusion complexes with synthetic polymers by phosphorylase-catalyzed enzymatic polymerization. Amylose is known to be synthesized by enzymatic polymerization using α-d-glucose 1-phosphate as a monomer, by phosphorylase catalysis. When the phosphorylase-catalyzed enzymatic polymerization was conducted in the presence of various hydrophobic polymers, such as polyethers, polyesters, poly(ester-ether), and polycarbonates as a guest polymer, such inclusion supramolecules were formed by the hydrophobic interaction in the progress of polymerization. Because the representation of propagation in the polymerization is similar to the way that a vine of a plant grows, twining around a rod, this polymerization method for the formation of amylose-polymer inclusion complexes was proposed to be named “vine-twining polymerization”. To yield an inclusion complex from a strongly hydrophobic polyester, the parallel enzymatic polymerization system was extensively developed. The author found that amylose selectively included one side of the guest polymer from a mixture of two resemblant guest polymers, as well as a specific range in molecular weights of the guest polymers poly(tetrahydrofuran) (PTHF) in the vine-twining polymerization. Selective inclusion behavior of amylose toward stereoisomers of chiral polyesters, poly(lactide)s, also appeared in the vine-twining polymerization. PMID:24970172

Complexation of carbendazim with hydroxypropyl-β-cyclodextrin to improve solubility and fungicidal activity.

PubMed

Ge, Xia; Huang, Zheng; Tian, Shilong; Huang, Yulong; Zeng, Chaozhen

2012-06-05

The effect of hydroxypropyl-β-cyclodextrin (HPβCD) on the improvement of the solubility and fungicidal activity of carbendazim (MBC) has been investigated. The inclusion complexation of HPβCD with MBC has been prepared and characterized by phase solubility diagram, fluorescence, (1)H NMR, ROESY and FT-IR spectra. The stoichiometric ratio and stability constant were determined by Job's plot and phase solubility studies, respectively. The inclusion complex MBC·HPβCD has exhibited different properties from MBC. The obtained inclusion complex was found to significantly improve the water solubility of MBC. In addition, the biological activity indicated that the complex displayed the better fungicidal activity than MBC. The present study provided useful information for a more rational application of MBC. Copyright © 2012 Elsevier Ltd. All rights reserved.

Spectral, thermal, and molecular modeling studies on the encapsulation of selected sulfonamide drugs in β-cyclodextrin nano-cavity

NASA Astrophysics Data System (ADS)

Bani-Yaseen, Abdulilah Dawoud; Mo'ala, Abeer

2014-10-01

In the present work the inclusion complexation of three sulfonamide (SA) drugs, namely sulfisoxazole (SSX), sulfamethizole (SMZ), and Sulfamethazine (STM) with β-cyclodextrin (β-CD) has been investigated using UV-Vis spectroscopy, DSC, 1H NMR spectroscopy, and molecular modeling methods. The binding constant (Kb) of SA:β-CD inclusion complexation was determined via applying the modified form of Benesi-Hildebrand equation employing the changes in absorbance at λmax. Obtained results revealed that SA drugs form 1:1 inclusion complex with β-CD with Kb of 650, 1532, 714 M-1 at 25 °C for SSX, SMZ, and STM, respectively. The UV-Vis absorption spectra displayed solvatochromic behavior of bathochromic shift with decreasing solvent polarity that in turn is good agreement with their behavior in the presence of β-CD in terms of environment polarity dependency. The inclusion complex formation between β-CD and tested SA drugs in liquid and solid states was confirmed by 1H NMR and DSC, respectively. Using semi-empirical quantum chemistry methods at PM3 theoretical level, inclusion complexes' structures as well as energetic and thermodynamic parameters of encapsulation were elucidated. Obtained results revealed that the encapsulation is favorably energetic and enthalpic in nature with the inclusion of the aniline moiety through the wide rim side of β-CD nano-cavity. Further, molecular modeling revealed that β-CD encapsulation of SA drugs reduced their (EHOMO - ELUMO) gap.

Preparation, characterization and binding behaviors of host-guest inclusion complexes of metoclopramide hydrochloride with α- and β-cyclodextrin molecules

NASA Astrophysics Data System (ADS)

Barman, Siti; Barman, Biraj Kumar; Roy, Mahendra Nath

2018-03-01

The supramolecular interaction of metoclopramide hydrochloride (MP) with α-cyclodextrin (α-CD) and β-cyclodextrin (β-CD) has been inspected by ultraviolet-visible (UV-vis) light, infra-red (IR) light, fluorescence and 1H NMR spectroscopy. The formation of an inclusion complex greatly affects the physical-chemical properties of the guest molecules, such as solubility, chemical reactivity and the spectroscopic and electrochemical properties. Thus the changes in the spectral properties and physico-chemical properties confirm the inclusion complex formation. Surface tension, conductivity studies and Job's plot indicate a 1: 1 stoichiometry of the MP:CD host-guest inclusion complexes. The binding/association constants have been evaluated by both UV-Vis and fluorescence spectroscopic study indicating a higher degree of encapsulation for β-cyclodextrin (β-CD). Furthermore, the negative value of thermodynamic parameter (ΔG°) of the host-guest system suggests that the inclusion process proceeded spontaneously at 298.15 K. Based on the NMR data, the plausible mode of interaction of MP:α-CD and MP:β-CD complexes were proposed, which suggested that lipophilic aromatic ring of the MP entered into the cavity of CDs from the wider side, with the amide (sbnd CONH) and methoxy (-OMe) residues inside the CD cavity.

Potentiation of pH-sensitive polymer-modified liposomes with cationic lipid inclusion as antigen delivery carriers for cancer immunotherapy.

PubMed

Yoshizaki, Yuta; Yuba, Eiji; Sakaguchi, Naoki; Koiwai, Kazunori; Harada, Atsushi; Kono, Kenji

2014-09-01

Cationic lipid-incorporated liposomes modified with pH-sensitive polymers were prepared by introducing 3, 5-didodecyloxybenzamidine as a cationic lipid to egg yolk phosphatidylcholine liposomes modified with 3-methylglutarylated hyperbranched poly(glycidol) (MGlu-HPG) as a pH-sensitive polymer. These liposomes were stable at neutral pH, but were destabilized below pH 6.0 because MGlu-HPG changed its characteristics from hydrophilic to hydrophobic in response to the pH decrease. Cationic lipid inclusion improved their pH sensitivity at weakly acidic pH and association of liposomes with murine dendritic cell (DC) lines. Cationic lipid-incorporated liposomes delivered entrapped ovalbumin (OVA) molecules not only to cytosol but also to endosome/lysosome. Treatment with cationic lipid-incorporated liposomes induced up-regulation of antigen presentation-involved molecules on DCs, the promotion of cytokine production, and antigen presentation via both major histocompatibility complex (MHC) class I and II molecules. Especially, antigen presentation via MHC class II was promoted by cationic lipid inclusion, which might correspond to efficient endosome/lysosome delivery of OVA. Subcutaneous administration of OVA-loaded cationic lipid-incorporated liposomes induced antigen-specific antibody production in serum and Th1-dominant immune responses in the spleen. Furthermore, administration of the cationic lipid-incorporated liposomes to mice bearing E.G7-OVA tumor more significantly reduced the tumor volume than liposomes without cationic lipids. Therefore, cationic lipid inclusion into pH-sensitive polymer-modified liposomes, which can achieve both efficient antigen intracellular delivery and activation of antigen presenting cell, is an effective approach to develop antigen carriers for efficient cancer immunotherapy. Copyright © 2014 Elsevier Ltd. All rights reserved.

Study on vitamin K 3-cyclodextrin inclusion complex and analytical application

NASA Astrophysics Data System (ADS)

Zhenming, Dong; Xiuping, Liu; Guomei, Zhang; Shaomin, Shuang; Jinghao, Pan

2003-07-01

The inclusion interaction of the complexes between Vitamin K3 (VK3) and β-cyclodextrin (β-CD), hydroxypropyl-β-cyclodextrin (HP-β-CD) and sulfobutylether-β-cyclodextrin (SBE-β-CD) were studied by using steady-state fluorescence measurements. The various factors affecting the inclusion process were examined in detail. The formation constants and inclusion stoichiometry for VK3-CDs were determined. The results showed that the inclusion ability of β-CD and its derivatives was the order: SBE-β-CD>HP-β-CD>β-CD. The related inclusion mechanism is proposed to explain the inclusion process. A method of determining VK3 was established with the linear range was 2.5×10-6-5.0×10-4 M, and was used to determine the VK3 tablets. The recoveries were in the range of 97.52-103.5%. The results were satisfactory.

Closed-form solution for Eshelby's elliptic inclusion in antiplane elasticity using complex variable

NASA Astrophysics Data System (ADS)

Chen, Y. Z.

2013-12-01

This paper provides a closed-form solution for the Eshelby's elliptic inclusion in antiplane elasticity. In the formulation, the prescribed eigenstarins are not only for the uniform distribution, but also for the linear form. After using the complex variable and the conformal mapping, the continuation condition for the traction and displacement along the interface in the physical plane can be reduced to a condition along the unit circle. The relevant complex potentials defined in the inclusion and the matrix can be separated from the continuation conditions of the traction and displacement along the interface. The expressions of the real strains and stresses in the inclusion from the assumed eigenstrains are presented. Results for the case of linear distribution of eigenstrain are first obtained in the paper.

Host-guest inclusion system of ferulic acid with p-Sulfonatocalix[n]arenes: Preparation, characterization and antioxidant activity

NASA Astrophysics Data System (ADS)

Chao, Jianbin; Wang, Huijuan; Song, Kailun; Wang, Yongzhao; Zuo, Ying; Zhang, Liwei; Zhang, Bingtai

2017-02-01

The inclusion complexes of ferulic acid (FA) with p-Sulfonatocalix[n]arenes (SCXn, n = 4, 6, 8) were prepared and characterized both in the solid state and in solution using fluorescence spectroscopy, 1H nuclear magnetic resonance (1H NMR), attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR), atomic force microscopy (AFM) and differential scanning calorimetry (DSC). The results show that FA is able to form inclusion complexes with SCXn in a molar ratio of 1:1, causing a significant decrease in the fluorescence intensity of FA. The association constant of the inclusion complexes was calculated from the fluorescence titration data. 1H NMR spectroscopy analysis demonstrates that the aromatic ring and methoxy group of FA are partially covered by SCXn.

Encapsulation of citral isomers in extracted lemongrass oil with cyclodextrins: molecular modeling and physicochemical characterizations.

PubMed

Rungsardthong Ruktanonchai, Uracha; Srinuanchai, Wanwisa; Saesoo, Somsak; Sramala, Issara; Puttipipatkhachorn, Satit; Soottitantawat, Apinan

2011-01-01

The complexation between two isomers of citral in lemongrass oil and varying types of cyclodextrins (CDs), α-CD, β-CD, and HP-β-CD, were studied by molecular modeling and physicochemical characterization. The results obtained revealed that the most favorable complex formation governing between citrals in lemongrass oil and CDs were found at a 1:2 mole ratio for all CDs. Complex formation between E-citral and CD was more favorable than between Z-citral and CD. The thermal stability of the inclusion complex was observed compared to the citral in the lemongrass oil. The release time course of citral from the inclusion complex was the diffusion control, and it correlated well with Avrami's equation. The release rate constants of the E- and Z-citral inclusion complexes at 50 °C, 50% RH were observed at 1.32×10(-2) h(-1) and 1.43×10(-2) h(-1) respectively.

Structural characterization and bioavailability of ternary nanoparticles consisting of amylose, α-linoleic acid and β-lactoglobulin complexed with naringin.

PubMed

Feng, Tao; Wang, Ke; Liu, Fangfang; Ye, Ran; Zhu, Xiao; Zhuang, Haining; Xu, Zhimin

2017-06-01

Naringin is a bioflavonoid that is rich in citrus plants and possesses enormous health benefits. However, the use of naringin as a nutraceutical is significantly limited by its low bioavailability. In this study, a novel water-soluble ternary nanoparticle material consisting of amylose, α-linoleic acid and β-lactoglobulin was developed to encapsulate naringin to improve its bioavailability. The physicochemical characteristics of the ternary nanoparticle-naringin inclusion complex were analysed by ultraviolet-visible spectroscopy (UV), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), high-resolution transmission electron microscopy (TEM), X-ray diffractometry (XRD) and particle size distribution. The results confirmed the formation of the ternary nanoparticle-naringin inclusion complex. The encapsulation efficiency (EE) and loading content (LC) of the ternary nanoparticle-naringin inclusion complex were 78.73±4.17% and 14.51±3.43%, respectively. In addition, the results of the ternary nanoparticle-naringin inclusion complex in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) demonstrated that naringin can be gradually released from the complex. In conclusion, ternary nanoparticles are considered promising carriers to effectively improve the bioavailability of naringin. Copyright © 2017 Elsevier B.V. All rights reserved.

Inclusion compounds between α-, β- and γ-cyclodextrins: iron II lactate: a theoretical and experimental study using diffusion coefficients and molecular mechanics

NASA Astrophysics Data System (ADS)

Leite, Rosiley A.; Lino, Antonio C. S.; Takahata, Yuji

2003-01-01

The inclusion compounds between iron II lactate and three different cyclodextrins (CDs) were studied by means of experimental and theoretical data. The importance of iron II in the human metabolism effort the necessity of a minimum concentration to the human life. Malnutrition is one great problem in social politics of many countries on the world. The possibility to the development of novel medicines with the iron II species stable look for an increase on the efficiency for this kind of aid. Kinetics measurements confirm the possibility to stop the oxidation reaction. It was the first indication of efficient molecular encapsulation. Diffusion coefficient measurements were carried out by Taylor-Aris diffusion technique. The decrease of diffusion coefficients measured for iron II lactate when alone and forming the inclusion complexes was obtained for all hosts molecules used. Molecular Mechanics calculations were performed to elucidate the perfect arrange of iron II lactate inside CDs cavity. No great differences were obtained to the binding energy for the different hosts. Using the software HyperChem6.03v MM+, AMBER94 and OPLS Forced Fields for iron atom in two chemical environments (a) vacuum and (b) with addition of 250 water molecules (MM+). The solvent treatment was decisive to the order of stability. This order was β-CD>γ-CD>α-CD, the same order of solubility in water. The results contained in this work confirm the possibility to protect iron II lactate against oxidation.

Nanostructures formed by cyclodextrin covered procainamide through supramolecular self assembly - Spectral and molecular modeling study

NASA Astrophysics Data System (ADS)

Rajendiran, N.; Mohandoss, T.; Sankaranarayanan, R. K.

2015-02-01

Inclusion complexation behavior of procainamide (PCA) with two cyclodextrins (α-CD and β-CD) were analyzed by absorption, fluorescence, scanning electron microscope (SEM), transmission electron microscope (TEM), Raman image, FT-IR, differential scanning colorimeter (DSC), Powder X ray diffraction (XRD) and 1H NMR. Blue shift was observed in β-CD whereas no significant spectral shift observed in α-CD. The inclusion complex formation results suggest that water molecules also present in the inside of the CD cavity. The present study revealed that the phenyl ring of the PCA drug is entrapped in the CD cavity. Cyclodextrin studies show that PCA forms 1:2 inclusion complex with α-CD and β-CD. PCA:α-CD complex form nano-sized particles (46 nm) and PCA:β-CD complex form self-assembled to micro-sized tubular structures. The shape-shifting of 2D nanosheets into 1D microtubes by simple rolling mechanism were analysed by micro-Raman and TEM images. Thermodynamic parameters (ΔH, ΔG and ΔS) of inclusion process were determined from semiempirical PM3 calculations.

Crystal structures and molecular dynamics studies of the inclusion compounds of β-citronellol in β-cyclodextrin, heptakis(2,6-di-O-methyl)-β-cyclodextrin and heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin

NASA Astrophysics Data System (ADS)

Fourtaka, Katerina; Christoforides, Elias; Mentzafos, Dimitris; Bethanis, Kostas

2018-06-01

The crystal structures of the inclusion complexes of the β-citronellol (cl) inβ-Cyclodextrin (β-CD), heptakis(2,6-di-O-methyl)-β-Cyclodextrin (DM-β-CD) and heptakis(2,3,6-tri-O-methyl)-β-Cyclodextrin (TM-β-CD) have being investigated by X-ray crystallography. The cl/β-CD inclusion complex crystallizes in the P1space group forming dimers which are arranged along the c-axis according to the Intermediate Channel packing mode. Inside the dimeric host cavity two enantiomeric guest molecules are accommodated. The inclusion complexes of cl/DM-β-CD and cl/TM-β-CD crystallize in the P212121 space group having both 1:1 guest:host stoichiometry, the guest found always with the (-)-cl enantiomeric configuration. The guest is fully encapsulated inside the DM-β-CD host cavity whereas is partially encapsulated in the TM-β-CD which is severely puckered as in all TM-β-CD complexes and its primary side is efficiently blocked by the methoxy groups. The complex units in the case of cl/DM-β-CD pack along the crystallographic a-axis in a head-to-tail manner forming columns of herringbone mode whereas in the case of cl/TM-β-CD are arranged also head-to-tail, parallel to the b-axis, in a screw-channel mode. MD simulations based on the determined crystal structures showed that in a simulated aqueous environment the guest maintains the inclusion mode observed crystallographically in every case. MM/GBSA-calculations used for comparison of the inclusion complexes binding affinity with each other, indicated that the inclusion of β-citronellol in TM-β-CD is less favorable than in β-CD and DM-β-CD.

Inclusion complexes of cypermethrin and permethrin with monochlorotriazinyl-beta-cyclodextrin: A combined spectroscopy, TG/DSC and DFT study

NASA Astrophysics Data System (ADS)

Yao, Qi; You, Bin; Zhou, Shuli; Chen, Meng; Wang, Yujiao; Li, Wei

2014-01-01

The suitable size hydrophobic cavity and monochlorotriazinyl group as a reactive anchor make MCT-β-CD to be widely used in fabric finishing. In this paper, the inclusion complexes of monochlorotriazinyl-beta-cyclodextrin (MCT-β-CD) with cypermethrin (CYPERM) and permethrin (PERM) are synthesized and analyzed by TG/DSC, FT-IR and Raman spectroscopy. TG/DSC reveals that the decomposed temperatures of inclusion complexes are lower by 25-30 °C than that of physical mixtures. DFT calculations in conjunction with FT-IR and Raman spectral analyses are used to study the structures of MCT-β-CD and their inclusion complexes. Four isomers of trisubstituted MCT-β-CD are designed and DFT calculations reveal that 1,3,5-trisubstituted MCT-β-CD has the lowest energy and can be considered as main component of MCT-β-CD. The ground-state geometries, vibrational wavenumbers, IR and Raman intensities of MCT-β-CD and their inclusion complexes were calculated at B3LYP/6-31G (d) level of theory. Upon examining the optimized geometry of inclusion complex, we find that the CYPERM and PERM are inserted into the toroid of MCT-β-CD from the larger opening. The band at 1646 cm-1 in IR and at 1668 cm-1 in Raman spectrum reveals that monochloroazinyl group of MCT-β-CD exists in ketone form but not in anion form. The noticeable IR and Raman shift of phenyl reveals that these two benzene rings of CYPERM and PERM stays inside the cavity of MCT-β-CD and has weak interaction with MCT-β-CD. This spectroscopy conclusion is consistent with theoretical predicted structure.

Synthesis, characterization and cytotoxic evaluation of inclusion complexes between Riparin A and β-cyclodextrin

NASA Astrophysics Data System (ADS)

Araújo, Éverton José Ferreira de; Silva, Oskar Almeida; Rezende-Júnior, Luís Mário; Sousa, Ian Jhemes Oliveira; Araújo, Danielle Yasmin Moura Lopes de; Carvalho, Rusbene Bruno Fonseca de; Pereira, Sean Telles; Gutierrez, Stanley Juan Chavez; Ferreira, Paulo Michel Pinheiro; Lima, Francisco das Chagas Alves

2017-08-01

This study performed a physicochemical characterization of the inclusion complex generated between Riparin A and β-cyclodextrin (Rip A/β-CD) and compared the cytotoxic potential of the incorporated Rip A upon Artemia salina larvae. Samples were analyzed by phase solubility diagram, dissolution profile, differential scanning calorimetry, X-ray diffraction, infrared spectroscopy, proton nuclear magnetic resonance, scanning electron microscopy and artemicidal action. Riparin A/β-cyclodextrin complexes presented increased water solubility, AL type solubility diagram and Kst constant of 373 L/mol. Thermal analysis demonstrated reduction of the melt peak of complexed Rip A at 116.2 °C. Infrared spectroscopy confirmed generation of inclusion complexes, 1H NMR pointed out the interaction with H-3 of β-CD cavities, alterations in the crystalline natures of Rip A when incorporated within β-CD were observed and inclusion complexes presented higher cytotoxic on A. salina nauplii, with CL50 value of 117.2 (84.9-161.8) μg/mL. So, Rip A was incorporated into β-CDs with high efficiency and water solubility of Rip A was improved. Such solubility was corroborated by cytotoxic evaluation and these outcomes support the improvement of biological properties for complexes between Riparin A/β-cyclodextrin.

Inclusion complex of benzocaine and β-cyclodextrin: 1H NMR and isothermal titration calorimetry studies

NASA Astrophysics Data System (ADS)

Mic, Mihaela; Pırnǎu, Adrian; Bogdan, Mircea; Turcu, Ioan

2013-11-01

The supramolecular structure of the inclusion complex of β-cyclodextrin with benzocaine in aqueous solution has been investigated by 1H NMR spectroscopy and isothermal titration nanocalorimetry (ITC). Analysis of 1H NMR data by continuous variation method indicates that the benzocaine: β-cyclodextrin inclusion complex occurs and has a 1:1 stoichiometry. Rotating frame NOE spectroscopy (ROESY) was used to ascertain the solution geometry of the host-guest complex which indicates that the benzocaine molecule was included with the aromatic ring into the cyclodextrin cavity. Although the affinity of benzocaine for cyclodextrin is relatively high, the association constant cannot be measured using ITC due to the low solubility of benzocaine in water.

The Proteome of the Isolated Chlamydia trachomatis Containing Vacuole Reveals a Complex Trafficking Platform Enriched for Retromer Components

PubMed Central

Fischer, Martina; Jehmlich, Nico; Rose, Laura; Koch, Sophia; Laue, Michael; Renard, Bernhard Y.; Schmidt, Frank; Heuer, Dagmar

2015-01-01

Chlamydia trachomatis is an important human pathogen that replicates inside the infected host cell in a unique vacuole, the inclusion. The formation of this intracellular bacterial niche is essential for productive Chlamydia infections. Despite its importance for Chlamydia biology, a holistic view on the protein composition of the inclusion, including its membrane, is currently missing. Here we describe the host cell-derived proteome of isolated C. trachomatis inclusions by quantitative proteomics. Computational analysis indicated that the inclusion is a complex intracellular trafficking platform that interacts with host cells’ antero- and retrograde trafficking pathways. Furthermore, the inclusion is highly enriched for sorting nexins of the SNX-BAR retromer, a complex essential for retrograde trafficking. Functional studies showed that in particular, SNX5 controls the C. trachomatis infection and that retrograde trafficking is essential for infectious progeny formation. In summary, these findings suggest that C. trachomatis hijacks retrograde pathways for effective infection. PMID:26042774

Cyclodextrin Inclusion Complex to Improve Physicochemical Properties of Herbicide Bentazon: Exploring Better Formulations

PubMed Central

Yáñez, Claudia; Cañete-Rosales, Paulina; Castillo, Juan Pablo; Catalán, Nicole; Undabeytia, Tomás; Morillo, Esmeralda

2012-01-01

The knowledge of the host-guest complexes using cyclodextrins (CDs) has prompted an increase in the development of new formulations. The capacity of these organic host structures of including guest within their hydrophobic cavities, improves physicochemical properties of the guest. In the case of pesticides, several inclusion complexes with cyclodextrins have been reported. However, in order to explore rationally new pesticide formulations, it is essential to know the effect of cyclodextrins on the properties of guest molecules. In this study, the inclusion complexes of bentazon (Btz) with native βCD and two derivatives, 2-hydroxypropyl-β-cyclodextrin (HPCD) and sulfobutylether-β-cyclodextrin (SBECD), were prepared by two methods: kneading and freeze-drying, and their characterization was investigated with different analytical techniques including Fourier transform infrared spectroscopy (FT-IR), differential thermal analysis (DTA), X-ray diffractometry (XRD) and differential pulse voltammetry (DPV). All these approaches indicate that Btz forms inclusion complexes with CDs in solution and in solid state, with a stoichiometry of 1∶1, although some of them are obtained in mixtures with free Btz. The calculated association constant of the Btz/HPCD complex by DPV was 244±19 M−1 being an intermediate value compared with those obtained with βCD and SBECD. The use of CDs significantly increases Btz photostability, and depending on the CDs, decreases the surface tension. The results indicated that bentazon forms inclusion complexes with CDs showing improved physicochemical properties compared to free bentazon indicating that CDs may serve as excipient in herbicide formulations. PMID:22952577

Generation of stable cell line by using chitosan as gene delivery system.

PubMed

Şalva, Emine; Turan, Suna Özbaş; Ekentok, Ceyda; Akbuğa, Jülide

2016-08-01

Establishing stable cell lines are useful tools to study the function of various genes and silence or induce the expression of a gene of interest. Nonviral gene transfer is generally preferred to generate stable cell lines in the manufacturing of recombinant proteins. In this study, we aimed to establish stable recombinant HEK-293 cell lines by transfection of chitosan complexes preparing with pDNA which contain LacZ and GFP genes. Chitosan which is a cationic polymer was used as gene delivery system. Stable HEK-293 cell lines were established by transfection of cells with complexes which were prepared with chitosan and pVitro-2 plasmid vector that contains neomycin drug resistance gene, beta gal and GFP genes. The transfection efficiency was shown with GFP expression in the cells using fluorescence microscopy. Beta gal protein expression in stable cells was examined by beta-galactosidase assay as enzymatically and X-gal staining method as histochemically. Full complexation was shown in the above of 1/1 ratio in the chitosan/pDNA complexes. The highest beta-galactosidase activity was obtained with transfection of chitosan complexes. Beta gal gene expression was 15.17 ng/ml in the stable cells generated by chitosan complexes. In addition, intensive blue color was observed depending on beta gal protein expression in the stable cell line with X-gal staining. We established a stable HEK-293 cell line that can be used for recombinant protein production or gene expression studies by transfecting the gene of interest.

Malachite green mediates homodimerization of antibody VL domains to form a fluorescent ternary complex with singular symmetric interfaces

PubMed Central

Szent-Gyorgyi, Chris; Stanfield, Robyn L.; Andreko, Susan; Dempsey, Alison; Ahmed, Mushtaq; Capek, Sara; Waggoner, Alan; Wilson, Ian A.; Bruchez, Marcel P.

2013-01-01

We report that a symmetric small molecule ligand mediates the assembly of antibody light chain variable domains (VLs) into a correspondent symmetric ternary complex with novel interfaces. The L5* Fluorogen Activating Protein (FAP) is a VL domain that binds malachite green dye (MG) to activate intense fluorescence. Crystallography of liganded L5* reveals a 2:1 protein:ligand complex with inclusive C2 symmetry, where MG is almost entirely encapsulated between an antiparallel arrangement of the two VL domains. Unliganded L5* VL domains crystallize as a similar antiparallel VL/VL homodimer. The complementarity determining regions (CDRs) are spatially oriented to form novel VL/VL and VL/ligand interfaces that tightly constrain a propeller conformer of MG. Binding equilibrium analysis suggests highly cooperative assembly to form a very stable VL/MG/VL complex, such that MG behaves as a strong chemical inducer of dimerization. Fusion of two VL domains into a single protein tightens MG binding over 1,000-fold to low picomolar affinity without altering the large binding enthalpy, suggesting that bonding interactions with ligand and restriction of domain movements make independent contributions to binding. Fluorescence activation of a symmetrical fluorogen provides a selection mechanism for the isolation and directed evolution of ternary complexes where unnatural symmetric binding interfaces are favored over canonical antibody interfaces. As exemplified by L5*, these self-reporting complexes may be useful as modulators of protein association or as high affinity protein tags and capture reagents. PMID:23978698

Improved hydroxypropyl methylcellulose (HPMC) films through incorporation of amylose-sodium palmitate inclusion complexes

USDA-ARS?s Scientific Manuscript database

Polymer film blends of hydroxypropyl methylcellulose (HPMC) and amylose-sodium palmitate inclusion complexes (Na-Palm) were produced with no plasticizer, and were observed to have improved physical and gas barrier properties as compared with pure HPMC. The crystalline amylose helices incorporating t...

Analyses of polycyclic aromatic hydrocarbon (PAH) and chiral-PAH analogues-methyl-β-cyclodextrin guest-host inclusion complexes by fluorescence spectrophotometry and multivariate regression analysis.

PubMed

Greene, LaVana; Elzey, Brianda; Franklin, Mariah; Fakayode, Sayo O

2017-03-05

The negative health impact of polycyclic aromatic hydrocarbons (PAHs) and differences in pharmacological activity of enantiomers of chiral molecules in humans highlights the need for analysis of PAHs and their chiral analogue molecules in humans. Herein, the first use of cyclodextrin guest-host inclusion complexation, fluorescence spectrophotometry, and chemometric approach to PAH (anthracene) and chiral-PAH analogue derivatives (1-(9-anthryl)-2,2,2-triflouroethanol (TFE)) analyses are reported. The binding constants (K b ), stoichiometry (n), and thermodynamic properties (Gibbs free energy (ΔG), enthalpy (ΔH), and entropy (ΔS)) of anthracene and enantiomers of TFE-methyl-β-cyclodextrin (Me-β-CD) guest-host complexes were also determined. Chemometric partial-least-square (PLS) regression analysis of emission spectra data of Me-β-CD-guest-host inclusion complexes was used for the determination of anthracene and TFE enantiomer concentrations in Me-β-CD-guest-host inclusion complex samples. The values of calculated K b and negative ΔG suggest the thermodynamic favorability of anthracene-Me-β-CD and enantiomeric of TFE-Me-β-CD inclusion complexation reactions. However, anthracene-Me-β-CD and enantiomer TFE-Me-β-CD inclusion complexations showed notable differences in the binding affinity behaviors and thermodynamic properties. The PLS regression analysis resulted in square-correlation-coefficients of 0.997530 or better and a low LOD of 3.81×10 -7 M for anthracene and 3.48×10 -8 M for TFE enantiomers at physiological conditions. Most importantly, PLS regression accurately determined the anthracene and TFE enantiomer concentrations with an average low error of 2.31% for anthracene, 4.44% for R-TFE and 3.60% for S-TFE. The results of the study are highly significant because of its high sensitivity and accuracy for analysis of PAH and chiral PAH analogue derivatives without the need of an expensive chiral column, enantiomeric resolution, or use of a polarized light. Published by Elsevier B.V.

Characteristics and carbon stable isotopes of fluids in the Southern Kerala granulites and their bearing on the source of CO2

NASA Technical Reports Server (NTRS)

Santosh, M.; Jackson, D. H.; Mattey, D. P.; Harris, N. B. W.

1988-01-01

Carbon dioxide-rich inclusions commonly occur in the banded charnockites and khondalites of southern Kerala as well as in the incipient charnockites formed by desiccation of gneisses along oriented zones. The combined high density fluid inclusion isochores and the range of thermometric estimates from mineral assemblages indicate entrapment pressures in the range of 5.4 to 6.1 Kbar. The CO2 equation of state barometry closely compares with the 5 plus or minus 1 Kbar estimate from mineral phases for the region. The isochores for the high density fluid inclusions in all the three rock types pass through the P-T domain recorded by phase equilibria, implying that carbon dioxide was the dominating ambient fluid species during peak metamorphic conditions. In order to constrain the source of fluids and to evaluate the mechanism of desiccation, researchers undertook detailed investigations of the carbon stable isotope composition of entrapped fluids. Researchers report here the results of preliminary studies in some of the classic localities in southern Kerala namely, Ponmudi, Kottavattom, Manali and Kadakamon.

Delay-induced Turing-like waves for one-species reaction-diffusion model on a network

NASA Astrophysics Data System (ADS)

Petit, Julien; Carletti, Timoteo; Asllani, Malbor; Fanelli, Duccio

2015-09-01

A one-species time-delay reaction-diffusion system defined on a complex network is studied. Traveling waves are predicted to occur following a symmetry-breaking instability of a homogeneous stationary stable solution, subject to an external nonhomogeneous perturbation. These are generalized Turing-like waves that materialize in a single-species populations dynamics model, as the unexpected byproduct of the imposed delay in the diffusion part. Sufficient conditions for the onset of the instability are mathematically provided by performing a linear stability analysis adapted to time-delayed differential equations. The method here developed exploits the properties of the Lambert W-function. The prediction of the theory are confirmed by direct numerical simulation carried out for a modified version of the classical Fisher model, defined on a Watts-Strogatz network and with the inclusion of the delay.

Is metabolic syndrome related with coronary artery disease severity and complexity: An observational study about IDF and AHA/NHLBI metabolic syndrome definitions.

PubMed

Aykan, Ahmet Çağrı; Gül, İlker; Kalaycıoğlu, Ezgi; Gökdeniz, Tayyar; Hatem, Engin; Menteşe, Ümit; Yıldız, Banu Şahin; Yıldız, Mustafa

2014-01-01

The aim of the present study was to assess the relation between metabolic syndrome (MS) and coronary artery disease (CAD) complexity, assessed by Syntax score (SS), and severity in non-diabetic patients with stable CAD who underwent coronary angiography, and to evaluate whether the MS defined by different definitions, including International Diabetes Federation (IDF) and American Heart Association/National Heart Lung Blood Institute (AHA/NHLBI) guidelines, similarly correlated with SS. The present study is cross sectional and observational with prospective inclusion of 248 consecutive patients (157 male) who underwent coronary angiography due to stable CAD. The prevalence of MS was 54.4% according to IDF definition and 50.4% according to AHA/NHLBI definition. MS score according to IDF definitions (r = 0.446, p < 0.001), MS score according to AHA/NHLBI definitions (r = 0.341, p < 0.001) were moderately correlated with SS. In Fisher r to z transformation test the correlations of the presence of MS according to IDF and AHA/NHLBI definitions with SS were not statistically significant (p = 0.168, z = -1.38). The systolic blood pressure (p < 0.001, B = 0.354, 95% CI = -0.308 to 0.228), diastolic blood pressure (p = 0.006, B = -0.194, 95% CI = -0.333 to -0.056), age (p = 0.014, B = 0.147, 95% CI = 0.029 to 0.264), left ventricular ejection fraction (p = 0.031, B = -0.150, 95% CI= -0.286 to -0.014), waist/hip circumference (p < 0.001, B = 45.713, 95% CI = 23.235 to 68.1919) and log10 high density lipoprotein (p < 0.001, B = -22.209, 95% CI = -33.298 to-11.119) were the independent predictors of SS in linear regression analysis. MS is associated with the presence and complexity of CAD. Besides the presence of discrepancy in the limits of waist circumference, both IDF and AHA/NHLBI criteria were similarly correlated with CAD complexity.

Investigation on the inclusion interaction of 4-sulfonatocalix[n]arenes with 1-(4-nitrophenyl)piperazine

NASA Astrophysics Data System (ADS)

Zhang, Yongbin; Chao, Jianbin; Zhao, Shuhui; Xu, Penghao; Wang, Hongfang; Guo, Zhiqiang; Liu, Diansheng

2014-11-01

The inclusion behaviors of 4-Sulfonatocalix[n]arenes (SCXn) (n = 4, 6, 8) with 1-(4-nitrophenyl)piperazine (NPP) were investigated by UV spectroscopy and fluorescence spectroscopy at different pH values (pH = 3.05, 6.50, 8.40). The UV absorption and fluorescence intensity of NPP remarkably increased in presence of SCXn revealing formation of the inclusion complexes between NPP and SCXn. Moreover, the formation constants (K) of inclusion complexes were also determined by the non-linear fitting method, and the obtained data showed that the formation constants decreased gradually with the increasing of the pH value. When the pH value was 3.05, the formation constant of NPP with SCX8 reached a maximum of 1.7 × 107 L mol-1. The stoichiometric ratio was verified to be 1:1 by the continuous variation method. Meanwhile FT-IR and DSC analysis also indicated that NPP could form the inclusion complex with SCXn. In order to explore the inclusion mechanism of NPP with SCXn, 1H NMR and molecular modeling studies were carried out and experimental results showed that the part of benzene ring of NPP penetrated into the hydrophobic cavity of SCXn.

Inclusion complexes of azadirachtin with native and methylated cyclodextrins: solubilization and binding ability.

PubMed

Liu, Yu; Chen, Guo-Song; Chen, Yong; Lin, Jun

2005-06-02

The inclusion complexation behavior of azadirachtin with several cyclodextrins and their methylated derivatives has been investigated in both solution and the solid state by means of XRD, TG-DTA, DSC, NMR, and UV-vis spectroscopy. The results show that the water solubility of azadirachtin was obviously increased after resulting inclusion complex with cyclodextrins. Typically, beta-cyclodextrin (beta-CD), dimethyl-beta-cyclodextrin (DMbetaCD), permethyl-beta-cyclodextrin (TMbetaCD), and hydroxypropyl-beta-cyclodextrin (HPbetaCD) are found to be able to solubilize azadirachtin to high levels up to 2.7, 1.3, 3.5, and 1.6 mg/mL (calculated as azadirachtin), respectively. This satisfactory water solubility and high thermal stability of the cyclodextrin-azadirachtin complexes, will be potentially useful for their application as herbal medicine or healthcare products.

Inclusion complex formation of ionic liquids with 4-sulfonatocalixarenes studied by competitive binding of berberine alkaloid fluorescent probe

NASA Astrophysics Data System (ADS)

Miskolczy, Zsombor; Biczók, László

2009-07-01

A clinically important natural isoquinoline alkaloid, berberine, was used as a fluorescent probe to study the encapsulation of 1-alkyl-3-methylimidazolium (C nMIm +) type ionic liquids in 4-sulfonato-substituted calix[4]arene (SCX4) and calix[6]arene (SCX6) at pH 2. Addition of ionic liquids to the aqueous solution of berberine-SCXn inclusion complexes brought about considerable fluorescence intensity diminution due to the extrusion of berberine from the macrocycle into the aqueous phase by the competitive inclusion of C nMIm + cation. The lengthening of the aliphatic side chain of the imidazolium moiety diminished the equilibrium constant of complexation with SCX4, but enhanced the stability of SCX6 complexes. Larger binding strength was found for SCX4.

Influence of chirality on vibrational and relaxational properties of (S)- and (R,S)-ibuprofen/methyl-β-cyclodextrin inclusion complexes: an INS and QENS study.

PubMed

Crupi, Vincenza; Guella, Graziano; Longeville, Stéphane; Majolino, Domenico; Mancini, Ines; Paciaroni, Alessandro; Rossi, Barbara; Venuti, Valentina

2013-10-03

In this paper, we analyze the internal picosecond dynamics of enantiomeric ((S)-) and racemic ((R,S)-) ibuprofen (IBP), when forming inclusion complexes, in solid state, with methyl-β-cyclodextrin (Me-β-CD), by inelastic and quasi elastic neutron scattering. The study was aimed at understanding, by the analysis of the vibrational and relaxational properties of the inclusion complexes also with respect to the single components, if and how the differences in the structural properties of the hydrogen bond (HB) network of (S)- and (R,S)-IBP can have influence on the complexation process triggered by "host-guest" interactions, whose detailed knowledge is retained as a prerequisite for enantiodiscrimination. From the results, a similar complexation mechanism for (S)- and (R,S)-IBP is argued, with a preferred penetration mode involving the isopropyl group of IBP.

Amylose-potassium oleate inclusion complex in plain set-style yogurt

USDA-ARS?s Scientific Manuscript database

Amylose-potassium oleate inclusion complex (AIC) were used to replace skim milk solids in yogurt. The effect of AIC on yogurt fermentation and small amplitude oscillatory shear flow measurements of storage and loss moduli were studied and compared to full fat samples. Texture, storage modulus, and s...

Poly(vinyl alcohol) composite films with high percent elongation prepared from amylose-fatty ammonium salt inclusion complexes

USDA-ARS?s Scientific Manuscript database

Amylose inclusion complexes prepared from cationic fatty ammonium salts and jet-cooked high amylose starch were combined with poly(vinyl alcohol) (PVOH) to form glycerol-plasticized films. Their tensile properties were compared with similar films prepared previously with analogous anionic fatty acid...

Rheological characterization of solutions and thin films made from amylose-hexadecylammonium chloride inclusion complexes and polyvinyl alcohol

USDA-ARS?s Scientific Manuscript database

The rheological properties of aqueous solutions and films made from blends of polyvinyl alcohol (PVOH) and amylose-hexadecylammonium chloride inclusion complexes (Hex-Am) were investigated to better understand the polymer interactions and processing parameters. Aqueous solutions of Hex-Am displayed ...

Water soluble biocompatible vesicles based on polysaccharides and oligosaccharides inclusion complexes for carotenoid delivery.

PubMed

Polyakov, Nikolay E; Kispert, Lowell D

2015-09-05

Since carotenoids are highly hydrophobic, air- and light-sensitive hydrocarbon compounds, developing methods for increasing their bioavailability and stability towards irradiation and reactive oxygen species is an important goal. Application of inclusion complexes of "host-guest" type with polysaccharides and oligosaccharides such as arabinogalactan, cyclodextrins and glycyrrhizin minimizes the disadvantages of carotenoids when these compounds are used in food processing (colors and antioxidant capacity) as well as for production of therapeutic formulations. Cyclodextrin complexes which have been used demonstrated enhanced storage stability but suffered from poor solubility. Polysaccharide and oligosaccharide based inclusion complexes play an important role in pharmacology by providing increased solubility and stability of lipophilic drugs. In addition they are used as drug delivery systems to increase absorption rate and bioavailability of the drugs. In this review we summarize the existing data on preparation methods, analysis, and chemical reactivity of carotenoids in inclusion complexes with cyclodextrin, arabinogalactan and glycyrrhizin. It was demonstrated that incorporation of carotenoids into the "host" macromolecule results in significant changes in their physical and chemical properties. In particular, polysaccharide complexes show enhanced photostability of carotenoids in water solutions. A significant decrease in the reactivity towards metal ions and reactive oxygen species in solution was also detected. Copyright © 2015 Elsevier Ltd. All rights reserved.

Increasing solubility of red bell pepper carotenoids by complexation with 2-hydroxypropyl-β-cyclodextrin.

PubMed

de Lima Petito, Nicolly; da Silva Dias, Daiana; Costa, Valéria Gonçalves; Falcão, Deborah Quintanilha; de Lima Araujo, Kátia Gome

2016-10-01

Red bell pepper carotenoids were complexed with 2-hydroxypropyl-β-cyclodextrin (2-HPβCD) in different mass ratios (1:4, 1:6, 1:8 and 1:10) through ultrasonic homogenization in order to increase carotenoid solubility and their use as natural pigment in food. Inclusion complexes, red bell pepper extract and physical mixtures were analyzed by DSC, FT-IR, (1)H NMR and DLS. Solubility assay was performed to identify the effect of complexation on the solubility of carotenoids. From characterization assays, results showed that inclusion process occurred for all tested ratios. Results for water solubility assays demonstrated clear differences between solubility index of inclusion complexes (8.06±2.59-16.55±4.40mg/mL) and physical mixtures (3.53±1.44-7.3±1.88mg/mL), while carotenoid extract was no water soluble, as expected. These results indicated that molecular inclusion of carotenoids in 2-HPβCD was efficient to enhance their solubility in water, enabling application of red bell pepper carotenoid as natural pigment and/or bioactive substances in food. Copyright © 2016 Elsevier Ltd. All rights reserved.

Intestinal Permeability of β-Lapachone and Its Cyclodextrin Complexes and Physical Mixtures.

PubMed

Mangas-Sanjuan, Victor; Gutiérrez-Nieto, Jorge; Echezarreta-López, Magdalena; González-Álvarez, Isabel; González-Álvarez, Marta; Casabó, Vicente-Germán; Bermejo, Marival; Landin, Mariana

2016-12-01

β-Lapachone (βLAP) is a promising, poorly soluble, antitumoral drug. βLAP combination with cyclodextrins (CDs) improves its solubility and dissolution but there is not enough information about the impact of cyclodextrins on βLAP intestinal permeability. The objectives of this work were to characterize βLAP intestinal permeability and to elucidate cyclodextrins effect on the dissolution properties and on the intestinal permeability. The final goal was to evaluate CDs influence on the oral absorption of βLAP. Binary systems (physical mixtures and inclusion complexes) including βLAP and CDs (β-cyclodextrin: βCD, random-methyl-β-cyclodextrin: RMβCD and sulfobutylether-β-cyclodextrin: SBEβCD) have been prepared and analysed by differential scanning calorimetry. βLAP (and its combinations with CDs) absorption rate coefficients and effective permeability values have been determined in vitro in MDCK or MDCK-Mdr1 monolayers and in situ in rat by a closed loop perfusion technique. DSC results confirmed the formation of the inclusion complexes. βLAP-CDs inclusion complexes improve drug solubility and dissolution rate in comparison with physical mixtures. βLAP presented a high permeability value which can provide complete oral absorption. Its oral absorption is limited by its low solubility and dissolution rate. Cyclodextrin (both as physical mixtures and inclusion complexes) showed a positive effect on the intestinal permeability of βLAP. Complexation with CDs does not reduce βLAP intestinal permeability in spite of the potential negative effect of the reduction in free fraction of the drug. The use of RMβCD or SBEβCD inclusion complexes could benefit βLAP oral absorption by enhancing its solubility, dissolution rate and permeability.

Hydroxypropyl-β-cyclodextrin for Delivery of Baicalin via Inclusion Complexation by Supercritical Fluid Encapsulation.

PubMed

Li, Ying; He, Zhen-Dan; Zheng, Qian-En; Hu, Chengshen; Lai, Wing-Fu

2018-05-14

Over the years, various methods have been developed to enhance the solubility of insoluble drugs; however, most of these methods are time-consuming and labor intensive or involve the use of toxic materials. A method that can safely and effectively enhance the solubility of insoluble drugs is lacking. This study adopted baicalin as an insoluble drug model, and used hydroxypropyl-β-cyclodextrin for the delivery of baicalin via the inclusion complexation by supercritical fluid encapsulation. Different parameters for the complex preparation as well as the physicochemical properties of the complex have been investigated. Our results showed that when compared to the conventional solution mixing approach, supercritical fluid encapsulation enables a more precise control of the properties of the complex, and gives higher loading and encapsulation efficiency. It is anticipated that our reported method can be useful in enhancing the preparation efficiency of inclusion complexes, and can expand the application potential of insoluble herbal ingredients in treatment development and pharmaceutical formulation.

Formation of Stable Cationic Lipid/DNA Complexes for Gene Transfer

NASA Astrophysics Data System (ADS)

Hofland, Hans E. J.; Shephard, Lee; Sullivan, Sean M.

1996-07-01

Stable cationic lipid/DNA complexes were formed by solubilizing cationic liposomes with 1% octylglucoside and complexing a DNA plasmid with the lipid in the presence of detergent. Removal of the detergent by dialysis yielded a lipid/DNA suspension that was able to transfect tissue culture cells up to 90 days after formation with no loss in activity. Similar levels of gene transfer were obtained by mixing the cationic lipid in a liposome form with DNA just prior to cell addition. However, expression was completely lost 24 hr after mixing. The transfection efficiency of the stable complex in 15% fetal calf serum was 30% of that obtained in the absence of serum, whereas the transient complex was completely inactivated with 2% fetal calf serum. A 90-day stability study comparing various storage conditions showed that the stable complex could be stored frozen or as a suspension at 4 degrees C with no loss in transfection efficiency. Centrifugation of the stable complex produced a pellet that contained approximately 90% of the DNA and 10% of the lipid. Transfection of cells with the resuspended pellet and the supernatant showed that the majority of the transfection activity was in the pellet and all the toxicity was in the supernatant. Formation of a stable cationic lipid/DNA complex has produced a transfection vehicle that can be stored indefinitely, can be concentrated with no loss in transfection efficiency, and the toxicity levels can be greatly reduced when the active complex is isolated from the uncomplexed lipid.

Spectroscopic methods for aqueous cyclodextrin inclusion complex binding measurement for 1,4-dioxane, chlorinated co-contaminants, and ozone

NASA Astrophysics Data System (ADS)

Khan, Naima A.; Johnson, Michael D.; Carroll, Kenneth C.

2018-03-01

Recalcitrant organic contaminants, such as 1,4-dioxane, typically require advanced oxidation process (AOP) oxidants, such as ozone (O3), for their complete mineralization during water treatment. Unfortunately, the use of AOPs can be limited by these oxidants' relatively high reactivities and short half-lives. These drawbacks can be minimized by partial encapsulation of the oxidants within a cyclodextrin cavity to form inclusion complexes. We determined the inclusion complexes of O3 and three common co-contaminants (trichloroethene, 1,1,1-trichloroethane, and 1,4-dioxane) as guest compounds within hydroxypropyl-β-cyclodextrin. Both direct (ultraviolet or UV) and competitive (fluorescence changes with 6-p-toluidine-2-naphthalenesulfonic acid as the probe) methods were used, which gave comparable results for the inclusion constants of these species. Impacts of changing pH and NaCl concentrations were also assessed. Binding constants increased with pH and with ionic strength, which was attributed to variations in guest compound solubility. The results illustrate the versatility of cyclodextrins for inclusion complexation with various types of compounds, binding measurement methods are applicable to a wide range of applications, and have implications for both extraction of contaminants and delivery of reagents for treatment of contaminants in wastewater or contaminated groundwater.

Inclusion bodies of aggregated hemosiderins in liver macrophages.

PubMed

Hayashi, Hisao; Tatsumi, Yasuaki; Wakusawa, Shinya; Shigemasa, Ryota; Koide, Ryoji; Tsuchida, Ken-Ichi; Morotomi, Natsuko; Yamashita, Tetsuji; Kumagai, Kotaro; Ono, Yukiya; Hayashi, Kazuhiko; Ishigami, Masatoshi; Goto, Hidemi; Kato, Ayako; Kato, Koichi

2017-12-01

Hemosiderin formation is a structural indication of iron overload. We investigated further adaptations of the liver to excess iron. Five patients with livers showing iron-rich inclusions larger than 2 µm were selected from our database. The clinical features of patients and structures of the inclusions were compared with those of 2 controls with mild iron overload. All patients had severe iron overload with more than 5000 ng/mL of serum ferritin. Etiologies were variable, from hemochromatosis to iatrogenic iron overload. Their histological stages were either portal fibrosis or cirrhosis. Inclusion bodies were ultra-structurally visualized as aggregated hemosiderins in the periportal macrophages. X-ray analysis always identified, in addition to a large amount of iron complexes including oxygen and phosphorus, a small amount of copper and sulfur in the mosaic matrixes of inclusions. There were no inclusions in the control livers. Inclusion bodies, when the liver is loaded with excess iron, may appear in the macrophages as isolated organella of aggregated hemosiderins. Trace amounts of copper-sulfur complexes were always identified in the mosaic matrices of the inclusions, suggesting cuproprotein induction against excess iron. In conclusion, inclusion formation in macrophages may be an adaptation of the liver loaded with excess iron.

Heterogenous Oxygen Isotopic Composition of a Complex Wark-Lovering Rim and the Margin of a Refractory Inclusion from Leoville

NASA Technical Reports Server (NTRS)

Simon, J. I.; Matzel, J. E. P.; Simon, S. B.; Weber, P. K.; Grossman, L.; Ross, D. K.; Hutcheon, I. D.

2014-01-01

Wark-Lovering (WL) rims [1] surrounding many refractory inclusions represent marker events in the early evolution of the Solar System in which many inclusions were exposed to changes in pressure [2], temperature [3], and isotopic reservoirs [4-7]. The effects of these events can be complex, not only producing mineralogical variability of WL rims [2], but also leading to mineralogical [8-10] and isotopic [7, 11, 12] changes within inclusion interiors. Extreme oxygen isotopic heterogeneity measured in CAIs has been explained by mixing between distinct oxygen gas reservoirs in the nebula [13]. Some WL rims contain relatively simple mineral layering and/or are isotopically homogeneous [14, 15]. As part of a larger effort to document and understand the modifications observed in some CAIs, an inclusion (L6) with a complex WL rim from Leoville, a member of the reduced CV3 subgroup was studied. Initial study of the textures and mineral chemistry was presented by [16]. Here we present NanoSIMS oxygen isotopic measurements to complement these petrologic observations.

Thermal evolution of Site U1414 by stable isotopes δ13C and δ18O, 87Sr/86Sr and fluid inclusion analyses, IODP Expedition 344

NASA Astrophysics Data System (ADS)

Brandstätter, Jennifer; Kurz, Walter; Krenn, Kurt; Richoz, Sylvain

2017-04-01

IODP Expedition 344 is the second expedition in course of the Costa Rica Seismogenesis Project (Program A), that was designed to reveal processes that effect nucleation and seismic rupture of large earthquakes at erosional subduction zones. Site 344-U1414, located 1 km seaward of the deformation front offshore Costa Rica, serves to evaluate fluid-rock interaction and geochemical processes linked with the tectonic evolution of the incoming Cocos Plate from the Early Miocene up to recent times. Combined isotope analyses and microthermometric analyses of fluid inclusions of hydrothermal veins within lithified sediments and the igneous basement (Cocos Ridge basalt), was used to reveal the thermal history of Site 344-U1414. Veins in the sedimentary rocks are mainly filled by coarse-grained calcite and subordinately by quartz. Veins within the basalt show polymineralic filling of clay minerals, calcite, aragonite and quartz. Blocky veins with embedded wall rock fragments, appearing in the sediments and in the basalt, indicate hydraulic fracturing. The carbon isotopic composition of the vein calcite suggest the influence of a CO2 -rich fluid mixed with seawater (-3.0 to -0.4‰ V-PDB) and the δ18O values can be differentiated in two groups, depending on the formation temperature (-13.6 to -9.3‰ and -10.8 to -4.7‰ V-PDB). 87Sr/86Sr ratios from the veins confirm the results of the stable isotope analyses, with a higher 87Sr/86Sr ratio close to seawater composition and lower ratios indicating the influence of basalt alteration. The hydrothermal veins contain different types of fluid inclusions with high and low entrapment temperatures and low saline fluids. The occurrence of decrepitated fluid inclusions, formed by increased internal overpressure, is related to isobaric heating. Elongated fluid inclusion planes, arc-like fluid inclusions and low homogenization temperatures suggest subsequent isobaric cooling. The stable isotopic content, strontium isotopic composition and the results of fluid inclusion analyses indicate that the source of fluids is a mixture of mobilized pore water and invaded seawater that communicated with high temperature CO2-rich fluids. We propose that lithification of the sediments was accompanied with a first stage of vein development in the Middle Miocene and was a result of the Galapagos hotspot activity. Heat advection led to subsequent vein modification related to isobaric heating. The latest mineralization occurred during crustal cooling up to recent times.

A high resolution electron microscopy investigation of curvature in carbon nanotubes

NASA Astrophysics Data System (ADS)

Weldon, D. N.; Blau, W. J.; Zandbergen, H. W.

1995-07-01

Evidence for heptagon inclusion in multi-walled carbon nanotubes was sought in arc-produced carbon deposits. Transmission electron microscopy revealed many curved nanotubes although their relative abundance was low. Close examination of the micrographs in the regions of expected heptagon inclusion shows that the curvature is accomplished by folding or fracture of the lattice planes. This observed phenomenon contradicts the theoretical modelling studies which predict stable structures with negative curvature accomplished by heptagon/pentagon pairs. A possible explanation for curvature in single-walled tubes is presented based on a molecular mechanics geometry optimisation study of spa inclusion in a graphite sheet.

Extruded foams prepared from high amylose starch with sodium stearate to form amylose inclusion complexes

USDA-ARS?s Scientific Manuscript database

Starch foams were prepared from high amylose corn starch in the presence and absence of sodium stearate and PVOH to determine how the formation of amylose-sodium stearate inclusion complexes and the addition of PVOH would affect foam properties. Low extrusion temperatures were used, and X-ray diffra...

Properties of extruded starch-poly(methyl acrylate) graft copolymers prepared from spherulites formed from amylose-oleic acid inclusion complexes

USDA-ARS?s Scientific Manuscript database

Mixtures of high amylose corn starch and oleic acid were processed by steam jet-cooking, and the dispersions were rapidly cooled to yield amylose-oleic acid inclusion complexes as sub-micron spherulites and spherulite aggregates. Dispersions of these spherulite particles were then graft polymerized ...

Properties of amylose-oleic acid inclusion complexes from corn starch grafted with poly(methyl acrylate)

USDA-ARS?s Scientific Manuscript database

Corn starch granules have been previously investigated as fillers in polymers. In this study, much smaller particles in the form of spherulites produced by steam jet-cooking high-amylose corn starch and oleic acid to form amylose inclusion complexes were graft polymerized with methyl acrylate, both ...

Characterization of Cyclodextrin/Volatile Inclusion Complexes: A Review.

PubMed

Kfoury, Miriana; Landy, David; Fourmentin, Sophie

2018-05-17

Cyclodextrins (CDs) are a family of cyclic oligosaccharides that constitute one of the most widely used molecular hosts in supramolecular chemistry. Encapsulation in the hydrophobic cavity of CDs positively affects the physical and chemical characteristics of the guests upon the formation of inclusion complexes. Such a property is interestingly employed to retain volatile guests and reduce their volatility. Within this scope, the starting crucial point for a suitable and careful characterization of an inclusion complex is to assess the value of the formation constant (K f ), also called stability or binding constant. This task requires the application of the appropriate analytical method and technique. Thus, the aim of the present paper is to give a general overview of the main analytical tools used for the determination of K f values for CD/volatile inclusion complexes. This review emphasizes on the advantages, inconvenients and limits of each applied method. A special attention is also dedicated to the improvement of the current methods and to the development of new techniques. Further, the applicability of each technique is illustrated by a summary of data obtained from the literature.

Complexes between methyltestosterone and β-cyclodextrin for application in aquaculture production.

PubMed

Carvalho, Lucas Bragança de; Burusco, Kepa Koldo; Jaime, Carlos; Venâncio, Tiago; Carvalho, Aline Ferreira Souza de; Murgas, Luis David Solis; Pinto, Luciana de Matos Alves

2018-01-01

The inclusion complexes between 17-α-methyltestosterone (MT) and β-cyclodextrin (bCD) were prepared and characterized in dissolution and solid phase. The complex promoted a sixfold increment in solubility of the hormone. It has a limited solubility and stoichiometry of 2:1 (bCD:MT) determined by DSC, NMR and solubility experiments, the association constant Ka=2846Lmol -1 and complex fraction of 76% (assessed by DOSY-NMR, in (1:3) DMSO/D 2 O). The association constant obtained in water by the solubility isotherms is 7540Lmol -1 . 2D-ROESY experiments indicate the intermolecular orientation (complete inclusion of the hormone in the cavity). Simulations by molecular dynamics agreed with the formation of the inclusion complex 2:1. Release tests showed the slower release for the complexes, with 50% for lyophilization and 56% for malaxation. These results clearly demonstrate the complexation of MT in bCD, which formulations are promising for further applications involving this steroid in aquaculture, both for sexual reversal and in technologies of hormone in water sequestration. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characterization, phase solubility and molecular modeling of α-cyclodextrin/pyrimethamine inclusion complex

NASA Astrophysics Data System (ADS)

Araujo, Marcia Valeria Gaspar de; Macedo, Osmir F. L.; Nascimento, Cristiane da Cunha; Conegero, Leila Souza; Barreto, Ledjane Silva; Almeida, Luis Eduardo; Costa, Nivan Bezerra da; Gimenez, Iara F.

2009-02-01

An inclusion complex between the dihydrofolate reductase inhibitor pyrimethamine (PYR) and α-cyclodextrin (α-CD) was prepared and characterized. From the phase-solubility diagram, a linear increase of PYR solubility was verified as a function of α-CD concentration, suggesting the formation of a soluble complex. A 1:1 host-guest stoichiometry can be proposed according to the Job's plot, obtained from the difference of PYR fluorescence intensity in the presence and absence of α-CD. Differential scanning calorimetry (DSC) measurements provided additional evidences of complexation such as the absence of the endothermic peak assigned to the melting of the drug. The inclusion mode characterized by two-dimensional 1H NMR spectroscopy (ROESY) involves penetration of the p-chlorophenyl ring into the α-CD cavity, in agreement to the orientation optimized by molecular modeling methods.

1H NMR study of inclusion compounds of phenylurea derivatives in β-cyclodextrin

NASA Astrophysics Data System (ADS)

Dupuy, N.; Barbry, D.; Bria, M.; Marquis, S.; Vrielynck, L.; Kister, J.

2005-04-01

Proton nuclear magnetic resonance spectroscopy ( 1H NMR), which has become an important tool for the study "in situ" of β-cyclodextrin (β-CD) complexes, was used to study and structurally characterize the inclusion complexes formed between β-CD and isoproturon, fenuron, monuron and diuron. The high variation of the chemical shifts from the proton located inside the cavity (H-3, H-5 and H-6) coupled with the non variation of the one located outer sphere of the β-CD (H-1, H-2 and H-4) provided clear evidence of the inclusion phenomena. Two-dimensional rotating frame Overhauser effect spectroscopy (ROESY) experiments were carried out to further support the proposed inclusion mode.

The Inclusion of Inclusive Education in International Development: Lessons from Papua New Guinea

ERIC Educational Resources Information Center

Le Fanu, Guy

2013-01-01

A new "inclusive" curriculum has been introduced in Papua New Guinea, with significant levels of support from a bilateral development agency. The curriculum is inclusive in the sense that it is designed to meet the diverse, complex, and ever-changing needs of students. Research indicates the curriculum has been shaped by various…

Ibuprofen-in-cyclodextrin-in-W/O/W emulsion - Improving the initial and long-term encapsulation efficiency of a model active ingredient.

PubMed

Hattrem, Magnus N; Kristiansen, Kåre A; Aachmann, Finn L; Dille, Morten J; Draget, Kurt I

2015-06-20

A challenge in formulating water-in-oil-in-water (W/O/W) emulsions is the uncontrolled release of the encapsulated compound prior to application. Pharmaceuticals and nutraceuticals usually have amphipathic nature, which may contribute to leakage of the active ingredient. In the present study, cyclodextrins (CyDs) were used to impart a change in the relative polarity and size of a model compound (ibuprofen) by the formation of inclusion complexes. Various inclusion complexes (2-hydroxypropyl (HP)-β-CyD-, α-CyD- and γ-CyD-ibuprofen) were prepared and presented within W/O/W emulsions, and the initial and long-term encapsulation efficiency was investigated. HP-β-CyD-ibuprofen provided the highest encapsulation of ibuprofen in comparison to a W/O/W emulsion with unassociated ibuprofen confined within the inner water phase, with a four-fold increase in the encapsulation efficiency. An improved, although lower, encapsulation efficiency was obtained for the inclusion complex γ-CyD-ibuprofen in comparison to HP-β-CyD-ibuprofen, whereas α-CyD-ibuprofen had a similar encapsulation efficiency to that of unassociated ibuprofen. The lower encapsulation efficiency of ibuprofen in combination with α-CyD and γ-CyD was attributed to a lower association constant for the γ-CyD-ibuprofen inclusion complex and the ability of α-CyD to form inclusion complexes with fatty acids. For the W/O/W emulsion prepared with HP-β-CyD-ibuprofen, the highest encapsulation of ibuprofen was obtained at hyper- and iso-osmotic conditions and by using an excess molar ratio of CyD to ibuprofen. In the last part of the study, it was suggested that the chemical modification of the HP-β-CyD molecule did not influence the encapsulation of ibuprofen, as a similar encapsulation efficiency was obtained for an inclusion complex prepared with mono-1-glucose-β-CyD. Copyright © 2015 Elsevier B.V. All rights reserved.

Palaeoclimate determination from cave calcite deposits

NASA Astrophysics Data System (ADS)

Gascoyne, M.

Calcite deposits formed in limestone caves have been found to be an excellent repository of palaeoclimatic data for terrestrial environments. The very presence of a relict deposit indicates non-glacial conditions at the time of formation, and both 14C and uranium-series methods can be used to date the deposit and, hence, the age of these climatic conditions. Variations in 13C and 18O content of the calcite, in 2H and 18O content of fluid inclusions, in trace element concentrations and, more recently, in pollen assemblages trapped in the calcite, are all potentially available as synchronous palaeoclimatic indicators. Previous work has tended to concentrate mainly on abundance of deposits as a palaeoclimatic indicator for the last 300,000 years. This literature is briefly reviewed here, together with the theory and methods of analysis of the U-series and stable isotopic techniques. The combined use of U-series ages and 13C and 18O variations in cave calcites illustrates the potential for palaeoclimate determination. Previously unpublished results of stable isotopic variations in dated calcites from caves in northern England indicate the level of detail of stable isotopic variations and time resolution that can be obtained, and the complexity of interpretation that may arise. Tentative palaeoclimatic signals for the periods 90-125 ka and 170-300 ka are presented. More comprehensive studies are needed in future work, especially in view of the difficulty in obtaining suitable deposits and the ethics of cave deposits conservation.

Recycling of crustal materials through study of ultrahigh-pressure minerals in collisional orogens, ophiolites, and mantle xenoliths: A review

NASA Astrophysics Data System (ADS)

Liou, Juhn G.; Tsujimori, Tatsuki; Yang, Jingsui; Zhang, R. Y.; Ernst, W. G.

2014-12-01

Newly recognized occurrences of ultrahigh-pressure (UHP) minerals including diamonds in ultrahigh-temperature (UHT) felsic granulites of orogenic belts, in chromitites associated with ophiolitic complexes, and in mantle xenoliths suggest the recycling of crustal materials through deep subduction, mantle upwelling, and return to the Earth's surface. This circulation process is supported by crust-derived mineral inclusions in deep-seated zircons, chromites, and diamonds from collision-type orogens, from eclogitic xenoliths in kimberlites, and from chromitities of several Alpine-Himalayan and Polar Ural ophiolites; some of these minerals contain low-atomic number elements typified by crustal isotopic signatures. Ophiolite-type diamonds in placer deposits and as inclusions in chromitites together with numerous highly reduced minerals and alloys appear to have formed near the mantle transition zone. In addition to ringwoodite and inferred stishovite, a number of nanometric minerals have been identified as inclusions employing state-of-the-art analytical tools. Reconstitution of now-exsolved precursor UHP phases and recognition of subtle decompression microstructures produced during exhumation reflect earlier UHP conditions. For example, Tibetan chromites containing exsolution lamellae of coesite + diopside suggest that the original chromitites formed at P > 9-10 GPa at depths of >250-300 km. The precursor phase most likely had a Ca-ferrite or a Ca-titanite structure; both are polymorphs of chromite and (at 2000 °C) would have formed at minimum pressures of P > 12.5 or 20 GPa respectively. Some podiform chromitites and host peridotites contain rare minerals of undoubted crustal origin, including zircon, feldspars, garnet, kyanite, andalusite, quartz, and rutile; the zircons possess much older U-Pb ages than the time of ophiolite formation. These UHP mineral-bearing chromitite hosts evidently had a deep-seated evolution prior to extensional mantle upwelling and partial melting at shallow depths to form the overlying ophiolite complexes. These new findings together with stable isotopic and inclusion characteristics of diamonds provide compelling evidence for profound underflow of both oceanic and continental lithosphere, recycling of surface 'organic' carbon into the lower mantle, and ascent to the Earth's surface through mantle upwelling. Intensified study of UHP granulite-facies lower crustal basement and ophiolitic chromitites should allow a better understanding of the geodynamics of subduction and crustal cycling.

Jealousy Graphs: Structure and Complexity of Decentralized Stable Matching

DTIC Science & Technology

2013-01-01

REPORT Jealousy Graphs: Structure and Complexity of Decentralized Stable Matching 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: The stable matching...Franceschetti 858-822-2284 3. DATES COVERED (From - To) Standard Form 298 (Rev 8/98) Prescribed by ANSI Std. Z39.18 - Jealousy Graphs: Structure and...market. Using this structure, we are able to provide a ner analysis of the complexity of a subclass of decentralized matching markets. Jealousy

Inclusive Education as Complex Process and Challenge for School System

ERIC Educational Resources Information Center

Al-Khamisy, Danuta

2015-01-01

Education may be considered as a number of processes, actions and effects affecting human being, as the state or level of the results of these processes or as the modification of the functions, institutions and social practices roles, which in the result of inclusion become new, integrated system. Thus this is very complex process. Nowadays the…

Commentary on the Inclusion of Persistent Complex Bereavement-Related Disorder in DSM-5

ERIC Educational Resources Information Center

Boelen, Paul A.; Prigerson, Holly G.

2012-01-01

The DSM-5 Anxiety, Obsessive-Compulsive Spectrum, Posttraumatic, and Dissociative Disorders Work Group has proposed criteria for Persistent Complex Bereavement-Related Disorder (PCBRD) for inclusion in the appendix of DSM-5. The authors feel that it is important that dysfunctional grief will become a formal condition in DSM-5 because that would…

Higher value films prepared from poly(vinyl alcohol) and amylose-fatty acid derivatives inclusion complexes

USDA-ARS?s Scientific Manuscript database

Water soluble amylose fatty acid and fatty ammonium salt inclusion complexes (AIC) were prepared by jet cooked high amylose corn starch with water soluble salts of long chain fatty acids or fatty amines. The formation of AIC was confirmed by X-ray diffraction of freeze-dried samples. After dissoluti...

Fluorimetric and mass spectrometric study of the interaction of β-cyclodextrin and osthole

NASA Astrophysics Data System (ADS)

Zhang, Huarong; Zhang, Hanqi; Qu, Chenling; Bai, Lifei; Ding, Lan

2007-11-01

The inclusion complex of β-cyclodextrin (β-CD) and osthole was studied by the electrospray ionization mass spectrometry (ESI-MS) and fluorescence spectrometry. From the mass spectrum, the 1:1 stoichiometric inclusion complex of β-CD and osthole was observed. The tandem mass spectrum was performed. The fluorescence intensity of osthole increased in the present of β-CD. According to the 1:1 β-CD-osthole mode, the dissociation constant ( KD) was obtained by ESI-MS and fluorescence spectrometry. The KD of β-CD-osthole inclusion complex is 6.96 × 10 -3 mol L -1 obtained by mass spectrometry and that is 8.14 × 10 -3 mol L -1 obtained by fluorescence spectrometry, which is consistent with each other.

A novel particle engineering technology to enhance dissolution of poorly water soluble drugs: spray-freezing into liquid.

PubMed

Rogers, True L; Nelsen, Andrew C; Hu, Jiahui; Brown, Judith N; Sarkari, Marazban; Young, Timothy J; Johnston, Keith P; Williams, Robert O

2002-11-01

A novel cryogenic spray-freezing into liquid (SFL) process was developed to produce microparticulate powders consisting of an active pharmaceutical ingredient (API) molecularly embedded within a pharmaceutical excipient matrix. In the SFL process, a feed solution containing the API was atomized beneath the surface of a cryogenic liquid such that the liquid-liquid impingement between the feed and cryogenic liquids resulted in intense atomization into microdroplets, which were frozen instantaneously into microparticles. The SFL micronized powder was obtained following lyophilization of the frozen microparticles. The objective of this study was to develop a particle engineering technology to produce micronized powders of the hydrophobic drug, danazol, complexed with hydroxypropyl-beta-cyclodextrin (HPbetaCD) and to compare these SFL micronized powders to inclusion complex powders produced from other techniques, such as co-grinding of dry powder mixtures and lyophilization of bulk solutions. Danazol and HPbetaCD were dissolved in a water/tetrahydrofuran cosolvent mixture prior to SFL processing or slow freezing. Identical quantities of the API and HPbetaCD used in the solutions were co-ground in a mortar and pestle and blended to produce a co-ground physical mixture for comparison. The powder samples were characterized by differential scanning calorimetry (DSC), powder X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR), scanning electron microscopy, surface area analysis, and dissolution testing. The results provided by DSC, XRD, and FTIR suggested the formation of inclusion complexes by both slow-freezing and SFL. However, the specific surface area was significantly higher for the latter. Dissolution results suggested that equilibration of the danazol/HPbetaCD solution prior to SFL processing was required to produce the most soluble conformation of the resulting inclusion complex following SFL. SFL micronized powders exhibited better dissolution profiles than the slowly frozen aggregate powder. Results indicated that micronized SFL inclusion complex powders dissolved faster in aqueous dissolution media than inclusion complexes formed by conventional techniques due to higher surface areas and stabilized inclusion complexes obtained by ultra-rapid freezing.

Synthesis and characterization of nano-encapsulated black pepper oleoresin using hydroxypropyl beta-cyclodextrin for antioxidant and antimicrobial applications.

PubMed

Teixeira, Bruna N; Ozdemir, Necla; Hill, Laura E; Gomes, Carmen L

2013-12-01

Previous studies have reported antimicrobial and antioxidant activity of black pepper oleoresin which is associated to its phenolic compounds and piperine. The ability of cyclodextrins to form an inclusion complex with a guest molecule could improve black pepper oleoresin application, bioavailability, and stability in foods. Hydroxypropyl beta-cyclodextrin (HPBCD) inclusion complex with black pepper olereosin were synthesized using the kneading method and characterized for its physico-chemical properties and its antioxidant and antimicrobial activities. Inclusion complex size was 103.9 ± 7.6 nm and indicated to be a polydisperse system. The entrapment efficiency was 78.3 ± 3.6%, which suggests that other constituents in black pepper oleoresin have higher affinities for HPBCD than piperine (major compound in black pepper oleoresin). Thermograms showed the disappearance of oxidation peaks of black pepper oleoresin, proving complex formation with HPBCD. Phase solubility results indicated 1:1 stoichiometric inclusion complex formation and an increase of black pepper oleoresin aqueous solubility with HPBCD concentration. Nano-encapsulation with HPBCD did not affect (P > 0.05) total phenolic content; however, it enhanced (P < 0.05) black pepper oleoresin antioxidant activity. Black pepper oleoresin and its inclusion complex were analyzed for their antimicrobial activity against Escherichia coli K12 and Salmonella enterica serovar Typhimurium LT2. Both free and encapsulated black pepper oleoresin effectively inhibited bacterial growth within the concentration range tested. Black pepper oleoresin encapsulated in HPBCD was able to inhibit Salmonella at lower (P < 0.05) concentrations than its corresponding free extract. Therefore, black pepper oleoresin-HPBCD nanocapsules could have important applications in the food industry as antimicrobial and antioxidant system. © 2013 Institute of Food Technologists®

The effect of specific solvent-solute interactions on complexation of alkali-metal cations by a lower-rim calix[4]arene amide derivative.

PubMed

Horvat, Gordan; Stilinović, Vladimir; Kaitner, Branko; Frkanec, Leo; Tomišić, Vladislav

2013-11-04

Complexation of alkali-metal cations with calix[4]arene secondary-amide derivative, 5,11,17,23-tetra(tert-butyl)-25,26,27,28-tetra(N-hexylcarbamoylmethoxy)calix[4]arene (L), in benzonitrile (PhCN) and methanol (MeOH) was studied by means of microcalorimetry, UV and NMR spectroscopies, and in the solid state by X-ray crystallography. The inclusion of solvent molecules (including acetonitrile, MeCN) in the calixarene hydrophobic cavity was also investigated. The classical molecular dynamics (MD) simulations of the systems studied were carried out. By combining the results obtained using the mentioned experimental and computational techniques, an attempt was made to get an as detailed insight into the complexation reactions as possible. The thermodynamic parameters, that is, equilibrium constants, reaction Gibbs energies, enthalpies, and entropies, of the investigated processes were determined and discussed. The stability constants of the 1:1 (metal:ligand) complexes measured by different methods were in very good agreement. Solution Gibbs energies of the ligand and its complexes with Na(+) and K(+) in methanol and acetonitrile were determined. It was established that from the thermodynamic point of view, apart from cation solvation, the most important reason for the huge difference in the stability of these complexes in the two solvents lay in the fact that the transfer of complex species from MeOH to MeCN was quite favorable. That could be at least partly explained by a more exergonic inclusion of the solvent molecule in the complexed calixarene cone in MeCN as compared to MeOH, which was supported by MD simulations. Molecular and crystal structures of the lithium cation complex of L with the benzonitrile molecule bound in the hydrophobic calixarene cavity were determined by single-crystal X-ray diffraction. As far as we are aware, for the first time the alkali-metal cation was found to be coordinated by the solvent nitrile group in a calixarene adduct. According to the results of MD simulations, the probability of such orientation of the benzonitrile molecule included in the ligand cone was by far the largest in the case of LiL(+) complex. Because of the favorable PhCN-Li(+) interaction, L was proven to have the highest affinity toward the lithium ion in benzonitrile, which was not the case in the other solvents examined (in acetonitrile, sodium complex was the most stable, whereas in methanol, complexation of lithium was not even observed). That could serve as a remarkable example showing the importance of specific solvent-solute interactions in determining the equilibrium in solution.

Synthetic H sub 2 O-CO sub 2 fluid inclusions in spontaneously nucleated forsterite, enstatite, and diopside hosts: The method and applications

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

Johnson, E.L.; Jenkins, D.M.

1991-04-01

This paper describes an experimental technique for the production of primary synthetic H{sub 2}O-CO{sub 2} and H{sub 2}O-CO{sub 2}-NaCl fluid inclusions in forsterite, orthopyroxene, and clinopyroxene hosts spontaneously nucleated during the incongruent dissolution of tremolite. The host producing reactions involve the complexation and transport of Ca, Mg, and SiO{sub 2} to the growing product phases in which the inclusions are hosted. This technique, therefore, provides the opportunity to study the effects of a complex host-producing reaction on the composition of the fluids trapped as primary inclusions in the growing host phase. In addition to providing a model for the entrapmentmore » of primary fluid inclusions, the reactions provide an excellent model of the onset of granulite facies metamorphism where, in nature, fluid inclusion compositions are commonly in disequilibrium with the mineral assemblages in which they are hosted.« less

Glass Inclusions and Melt Volatile Contents in the Late-Quaternary Basanites and Minettes of Colima (Mexico)

NASA Astrophysics Data System (ADS)

Maria, A. H.; Luhr, J. F.

2002-12-01

Olivine-hosted glass inclusions from fine tephra collected at three basanite-minette cinder cones on the lower flanks of the Colima Volcanic Complex in western Mexico were analyzed by electron microprobe and Fourier-transform infrared spectroscopy (FTIR). These nepheline-normative rocks have elemental-abundance patterns that mimic those of the volumetrically dominant subduction-related andesites, but at much higher abundance levels. Sr, Nd, and Pb isotopic ratios are also similar for the two suites. We interpret the Colima basanites and minettes as recording the "essence" of subduction-zone geochemistry, produced by nearly pure melting of phlogopite-rich veins in the mantle wedge, and erupted in western Mexico only because of its unusual upper crustal extensional regime. Similar melts impart the subduction-zone geochemical flavor to the dominant andesites, which differentiate from basalts produced by higher degrees of mantle wallrock melting. Olivine crystals separated from the basanite-minette tephra have Mg#s that range from 81.5 to 90.7. The 34 glass inclusions studied contain 49-60 wt.% SiO2 and include 2 with normative quartz, and 6 with normative hypersthene, with the remaining 26 containing up to 11.5% normative nepheline. The glasses also contain 2.8-8.4% K2O, 0.16-0.33% Cl, and 0.03-1.19% total sulfur as SO3. Comparison of Fe/Mg values of glass and host olivines indicates 1-5% crystallization of olivine from the inclusions following entrapment. FTIR measurements were made on 26 of the inclusions. No reliable carbonate or CO2 peaks were detected in any glass inclusion, but a significant 2350 cm-1 CO2 peak was found for a bubble completely trapped within one inclusion. Total water contents estimated from the 3535 cm-1 peak range from 0.2 % to 2.0%, with only 8 values above 1%. These relatively low water contents are surprising, especially for the phlogopite-bearing minettes. A value of 2.0% water corresponds to water saturation at a pressure of 415 bars, equivalent to a depth of 1600 m. We consider the possibility that the magmas ascended through much of the crust in a superheated condition, and stagnated in the uppermost crust where the bulk of the olivine crystals grew in a rapid skeletal fashion trapping the glass inclusions. Such stagnation is consistent with the complete lack of ultramafic xenoliths at these cones. Published phase-equilibrium experiments on an olivine-bearing minette imply that phlogopite is stable down to pressures of 200-400 bars, also consistent with this interpretation.

Structural evaluation of crystalline ternary γ-cyclodextrin complex.

PubMed

Higashi, Kenjirou; Ideura, Saori; Waraya, Haruka; Moribe, Kunikazu; Yamamoto, Keiji

2011-01-01

The structure of a crystalline γ-cyclodextrin (γ-CD) ternary complex containing salicylic acid (SA) and flurbiprofen (FBP) prepared by sealed heating was investigated. FBP/γ-CD inclusion complex was prepared by coprecipitation; its molar ratio was determined as 1/1. Powder X-ray diffraction measurements showed that the molecular packing of γ-CD changed from hexagonal to monoclinic columnar form by sealed heating of SA with dried FBP/γ-CD inclusion complex, indicating ternary complex formation. The stoichiometry of SA/FBP/γ-CD was estimated as 2/1/1. Solid-state transformation of γ-CD molecular packing upon water vapor adsorption and desorption was irreversible for this ternary complex, in contrast to the reversible transition for the FBP/γ-CD inclusion complex. The ternary complex contained one FBP molecule in the cavity of γ-CD and two SA molecules in the intermolecular space between neighboring γ-CD column stacks. Infrared and (13) C solid-state NMR spectroscopies revealed that the molecular states of SA and FBP changed upon ternary complex formation. In the complex, dimer FBP molecules were sandwiched between two γ-CD molecules whereas each monomer SA molecule was present in the intermolecular space of γ-CD. Ternary complex formation was also observed for other drug-guest systems using naproxen and ketoprofen. Thus, the complex can be used to formulate variety of drugs. Copyright © 2010 Wiley-Liss, Inc. and the American Pharmacists Association

A combined molecular dynamics simulation and quantum mechanics study on mercaptopurine interaction with the cucurbit [6,7] urils: Analysis of electronic structure

NASA Astrophysics Data System (ADS)

Zaboli, Maryam; Raissi, Heidar

2018-01-01

In the current study, the probability of complex formation between mercaptopurine drug with cucurbit[6]urils and cucurbit[7]urils has been investigated. The calculations for geometry optimization of complexes have been carried out by means of DFT (B3LYP), DFT-D (B3LYP-D) and M06-2X methods. The Atoms In Molecules (AIM), Natural Bond Orbital (NBO), NMR, the density of states (DOSs) and frontier molecular orbital (MO) analyses have been done on the inclusion complexes. In addition, the UV-Vis spectra of the first eight states have been obtained by CAM-B3LYP/TD-DFT calculation. The obtained results of the complexation process reveal that CB[7]-DRG complexes are more favorable than that of CB[6]-DRG interactions. Furthermore, our theoretical results show that configurations III and I are the most stable configurations related to the CB[6]/DRG and CB[7]/DRG interactions, respectively. The positive ∇2ρ(r) and HC values at the bond critical points indicate that exist the weak H-bonds between CB[6] and CB[7] with H atoms of the drug molecule. The obtained negative binding energy values of CB[7]-DRG interaction in solution phase show the stability of these complexes in the aqueous medium. Also, all of the observed parameters of molecular dynamics simulation such as the number of contacts, hydrogen bonding, center-of-mass distance and van der Waals energy values confirm the encapsulation of mercaptopurine molecule inside the cucurbit[7]urils cavity at about 3.2 ns.

Effect of β-Cyclodextrin Complexation on Solubility and Enzymatic Conversion of Naringin

PubMed Central

Cui, Li; Zhang, Zhen-Hai; Sun, E; Jia, Xiao-Bin

2012-01-01

In the present paper, the effect of β-cyclodextrin (β-CD) inclusion complexation on the solubility and enzymatic hydrolysis of naringin was investigated. The inclusion complex of naringin/β-CD at the molar ratio of 1:1 was obtained by the dropping method and was characterized by differential scanning calorimetry. The solubility of naringin complexes in water at 37 ± 0.1 °C was 15 times greater than that of free naringin. Snailase-involved hydrolysis conditions were tested for the bioconversion of naringin into naringenin using the univariate experimental design. Naringin can be transformed into naringenin by snailase-involved hydrolysis. The optimum conditions for enzymatic hydrolysis were determined as follows: pH 5.0, temperature 37 °C, ratio of snailase/substrate 0.8, substrate concentration 20 mg·mL−1, and reaction time 12 h. Under the optimum conditions, the transforming rate of naringenin from naringin for inclusion complexes and free naringin was 98.7% and 56.2% respectively, suggesting that β-CD complexation can improve the aqueous solubility and consequently the enzymatic hydrolysis rate of naringin. PMID:23203062

Curcumin complexation with cyclodextrins by the autoclave process: Method development and characterization of complex formation.

PubMed

Hagbani, Turki Al; Nazzal, Sami

2017-03-30

One approach to enhance curcumin (CUR) aqueous solubility is to use cyclodextrins (CDs) to form inclusion complexes where CUR is encapsulated as a guest molecule within the internal cavity of the water-soluble CD. Several methods have been reported for the complexation of CUR with CDs. Limited information, however, is available on the use of the autoclave process (AU) in complex formation. The aims of this work were therefore to (1) investigate and evaluate the AU cycle as a complex formation method to enhance CUR solubility; (2) compare the efficacy of the AU process with the freeze-drying (FD) and evaporation (EV) processes in complex formation; and (3) confirm CUR stability by characterizing CUR:CD complexes by NMR, Raman spectroscopy, DSC, and XRD. Significant differences were found in the saturation solubility of CUR from its complexes with CD when prepared by the three complexation methods. The AU yielded a complex with expected chemical and physical fingerprints for a CUR:CD inclusion complex that maintained the chemical integrity and stability of CUR and provided the highest solubility of CUR in water. Physical and chemical characterizations of the AU complexes confirmed the encapsulated of CUR inside the CD cavity and the transformation of the crystalline CUR:CD inclusion complex to an amorphous form. It was concluded that the autoclave process with its short processing time could be used as an alternate and efficient methods for drug:CD complexation. Copyright © 2017 Elsevier B.V. All rights reserved.

Additional Improvements to the NASA Lewis Ice Accretion Code LEWICE

NASA Technical Reports Server (NTRS)

Wright, William B.; Bidwell, Colin S.

1995-01-01

Due to the feedback of the user community, three major features have been added to the NASA Lewis ice accretion code LEWICE. These features include: first, further improvements to the numerics of the code so that more time steps can be run and so that the code is more stable; second, inclusion and refinement of the roughness prediction model described in an earlier paper; third, inclusion of multi-element trajectory and ice accretion capabilities to LEWICE. This paper will describe each of these advancements in full and make comparisons with the experimental data available. Further refinement of these features and inclusion of additional features will be performed as more feedback is received.

Interaction Mode between Inclusion Complex of Vitamin K3 with γ- Cyclodextrin and Herring-Sperm DNA.

PubMed

Tang, Yan; Cai, Li; Xue, Kang; Wang, Chunling; Xiong, Xiaoli

2016-05-03

Methods including spectroscopy, electronic chemistry and thermodynamics were used to study the inclusion effect between γ-cyclodextrin (CD) and vitamin K3(K3), as well as the interaction mode between herring-sperm DNA (hsDNA) and γ-CD-K3 inclusion complex. The results from ultraviolet spectroscopic method indicated that VK3 and γ-CD formed 1:1 inclusion complex, with the inclusion constant Kf = 1.02 × 10(4) L/mol, which is based on Benesi-Hildebrand's viewpoint. The outcomes from the probe method and Scatchard methods suggested that the interaction mode between γ-CD-K3 and DNA was a mixture mode, which included intercalation and electrostatic binding effects. The binding constants were K (θ)25°C = 2.16 × 10(4) L/mol, and K(θ)37°C = 1.06 × 10(4) L/mol. The thermodynamic functions of the interaction between γ-CD-K3 and DNA were ΔrHm(θ) = -2.74 × 10(4) J/mol, ΔrSm(θ) = 174.74 J·mol(-1)K(-1), therefore, both ΔrHm(θ) (enthalpy) and ΔrSm(θ) (entropy) worked as driven forces in this action.

Influence of the preparation method on the physicochemical properties of indomethacin and methyl-β-cyclodextrin complexes.

PubMed

Rudrangi, Shashi Ravi Suman; Bhomia, Ruchir; Trivedi, Vivek; Vine, George J; Mitchell, John C; Alexander, Bruce David; Wicks, Stephen Richard

2015-02-20

The main objective of this study was to investigate different manufacturing processes claimed to promote inclusion complexation between indomethacin and cyclodextrins in order to enhance the apparent solubility and dissolution properties of indomethacin. Especially, the effectiveness of supercritical carbon dioxide processing for preparing solid drug-cyclodextrin inclusion complexes was investigated and compared to other preparation methods. The complexes were prepared by physical mixing, co-evaporation, freeze drying from aqueous solution, spray drying and supercritical carbon dioxide processing methods. The prepared complexes were then evaluated by scanning electron microscopy, differential scanning calorimetry, X-ray powder diffraction, solubility and dissolution studies. The method of preparation of the inclusion complexes was shown to influence the physicochemical properties of the formed complexes. Indomethacin exists in a highly crystalline solid form. Physical mixing of indomethacin and methyl-β-cyclodextrin appeared not to reduce the degree of crystallinity of the drug. The co-evaporated and freeze dried complexes had a lower degree of crystallinity than the physical mix; however the lowest degree of crystallinity was achieved in complexes prepared by spray drying and supercritical carbon dioxide processing methods. All systems based on methyl-β-cyclodextrin exhibited better dissolution properties than the drug alone. The greatest improvement in drug dissolution properties was obtained from complexes prepared using supercritical carbon dioxide processing, thereafter by spray drying, freeze drying, co-evaporation and finally by physical mixing. Supercritical carbon dioxide processing is well known as an energy efficient alternative to other pharmaceutical processes and may have application for the preparation of solid-state drug-cyclodextrin inclusion complexes. It is an effective and economic method that allows the formation of solid complexes with a high yield, without the use of organic solvents and problems associated with their residues. Copyright © 2015 Elsevier B.V. All rights reserved.

"Everything the World Turns on": Inclusion and Exclusion in Linda Hogan's "Power"

ERIC Educational Resources Information Center

Peters, Jesse

2013-01-01

In her novel "Power," Linda Hogan provides readers with a close look at how separatism and syncretism, or exclusion and inclusion, are complex ideologies that lead to complex decisions. A close look at the novel reveals that the tensions and sharp dichotomies between the traditional world of the Taiga elders and the European American world,…

Key Players in Inclusion: Are We Meeting the Professional Needs of Learning Support Assistants for Pupils with Complex Needs?

ERIC Educational Resources Information Center

Abbott, Lesley; McConkey, Roy; Dobbins, Michael

2011-01-01

Under the aegis of inclusion, greater numbers of learning support assistants (LSAs) in mainstream and special schools are increasingly required to assist teachers with pupils who have complex needs across the full age range. Because of the numerous and wide-ranging learning difficulties and learning disabilities in addition to sensory impairment,…

Cu-Mo-Au mineralization in Qarachilar area, Qaradagh batholith (NW Iran): Fluid inclusion and stable isotope studies and Re-Os dating

NASA Astrophysics Data System (ADS)

Simmonds, Vartan; Moazzen, Mohssen

2015-04-01

The Qaradagh batholith is located in NW Iran, neighboring the Meghri-Ordubad granitoid in southern Armenia. This magmatic complex is emplaced in the northwestern part of the Urumieh-Dokhtar magmatic arc, which formed through north-eastward subduction of Neo-Tethyan oceanic crust beneath the central Iranian domain in the late-Mesozoic and early-Cenozoic and hosts most of the porphyry copper deposits and prospects in Iran, such as Sarcheshmeh and Sungun. The Qaradagh batholith is comprised of Eocene-Oligocene intrusive rocks occurring as multi-episode stocks, where the dominant rock type is granodiorite. Hydrothermal alterations have also occurred in these rocks including potassic, phyllic-sericitic, argillic and propylitic alterations and silicification. These alterations are accompanied by vein-type and disseminated Cu, Mo and Au mineralization. The Qarachilar area is located in the central part of the Qaradagh batholith, which hosts mono-mineralic and quartz-sulfide veins and veinlets (several mm to <1 m thick and 50-700 m long) and silicic zones containing Cu-Mo-Au-Ag ore minerals (mainly pyrite, chalcopyrite and molybdenite). Microthermometric studies on the fluid inclusions of quartz-sulfide veins-veinlets show that the salinity ranges between 15-70 wt% NaCl, with the highest peak between 35-40 wt% NaCl. The homogenization temperature for primary 2-phase and multi-phase inclusions ranges between 220 and 540 °C. Two-phase inclusions homogenizing by vapor disappearance have TH values between 280 and 440 °C (mainly between 300 and 360 °C). A few of them homogenize into vapor state with TH values of 440-540 °C. Multi-phase inclusions show 3 types of homogenization. Most of them homogenize by simultaneous disappearance of vapor bubble and dissolution of halite daughter crystal, for which the TH value is 240-420 °C (mostly between 260 and 340 °C). Those homogenizing by halite dissolution show TH values about 220-360 °C and a few homogenizing by vapor disappearance display TH values between 300 and 360 °C. The data-point trend in TH(L-V)-Salinity plot may signify boiling of low-salinity fluids and distillation by superficial fluids. Therefore, it can be concluded that the ore-forming magmatic-hydrothermal aqueous fluids have most likely experienced boiling and also mixed with low temperature and low salinity superficial fluids. Occurrence of boiling is also supported by the coexistence of liquid-rich and vapor-rich 2-phase inclusions as well as multi-phase halite-bearing inclusions which homogenize in a similar range of TH. The calculated minimum pressure at the time of entrapment is estimated about 50 to 120 bar, which is equal to the hydrostatic depth of 500-1100 m. Stable isotope studies of O, H and S on the quartz and sulfide samples taken from quartz-sulfide veins-veinlets reveal a magmatic origin for the ore-bearing fluid and its sulfur content. The δ18O values for quartz and fluid are about 11.13-12.47 ‰ and 5.78-6.89 ‰ (SMOW), respectively, the δD values are about -93 and -50 ‰ and the δ34S values of sulfide minerals are about -1.37-0.49‰ (VCDT). Re-Os model ages calculated for molybdenite samples range between 25.19±0.19 and 31.22±0.28 Ma, referring to middle-late Oligocene, contemporaneous with the third metallogenic epoch in the Lesser Caucasus (especially Kadjaran and Paragachai PCDs in South Armenian Block).

Educators' Experiences of Inclusive Learning Contexts: An Exploration of Competencies

ERIC Educational Resources Information Center

Magare, Ishmael; Kitching, Ansie Elizabeth; Roos, Vera

2010-01-01

The successful implementation of inclusive education relies heavily on educators. Inclusive education is based on values such as human dignity, equality, human rights and freedom. The complexity of the interactive relationships between different systems, such as learners, educators, families, schools and the learning context, was recognised in…

Kinetics of Inclusion Body Formation and Its Correlation with the Characteristics of Protein Aggregates in Escherichia coli

PubMed Central

Upadhyay, Arun K.; Murmu, Aruna; Singh, Anupam; Panda, Amulya K.

2012-01-01

The objective of the research was to understand the structural determinants governing protein aggregation into inclusion bodies during expression of recombinant proteins in Escherichia coli. Recombinant human growth hormone (hGH) and asparaginase were expressed as inclusion bodies in E.coli and the kinetics of aggregate formation was analyzed in details. Asparaginase inclusion bodies were of smaller size (200 nm) and the size of the aggregates did not increase with induction time. In contrast, the seeding and growth behavior of hGH inclusion bodies were found to be sequential, kinetically stable and the aggregate size increased from 200 to 800 nm with induction time. Human growth hormone inclusion bodies showed higher resistance to denaturants and proteinase K degradation in comparison to those of asparaginase inclusion bodies. Asparaginase inclusion bodies were completely solubilized at 2–3 M urea concentration and could be refolded into active protein, whereas 7 M urea was required for complete solubilization of hGH inclusion bodies. Both hGH and asparaginase inclusion bodies showed binding with amyloid specific dyes. In spite of its low β-sheet content, binding with dyes was more prominent in case of hGH inclusion bodies than that of asparaginase. Arrangements of protein molecules present in the surface as well as in the core of inclusion bodies were similar. Hydrophobic interactions between partially folded amphiphillic and hydrophobic alpha-helices were found to be one of the main determinants of hGH inclusion body formation. Aggregation behavior of the protein molecules decides the nature and properties of inclusion bodies. PMID:22479486

Effect of Adding Cerium on Microstructure and Morphology of Ce-Based Inclusions Formed in Low-Carbon Steel

PubMed Central

Adabavazeh, Z.; Hwang, W. S.; Su, Y. H.

2017-01-01

Intra-granular Acicular Ferrite (IAF), as one of the most well-known desirable microstructure of ferrite with a chaotic crystallographic orientation, can not only refine the microstructure and retard the propagation of cleavage crack but also provide excellent combination of strength and toughness in steel. The effect of adding cerium on microstructure and controlling proper cerium-based inclusions in order to improve properties in low-carbon commercial steel (SS400) were investigated. The type of inclusions can be controlled by changing S/O ratio and Ce content. Without Ce modification, MnS is a dominate inclusion. After adding Ce, the stable inclusion phases change from AlCeO3 to Ce2O2S. The optimum amount of cerium, 0.0235 wt.%, lead in proper grain refinement and formation of cerium oxide, oxy-sulfide and sulfide inclusions. Having a high amount of cerium results in increasing the number of inclusions significantly as a result it cannot be effective enough and the inclusions will act like barriers for others. It is found that the inclusions with a size of about 4∼7 μm can serve as heterogeneous nucleation sites for AF formation. Thermodynamic calculations have been applied to predict the inclusion formation in this molten steel as well, which show a good agreement with experimental one. PMID:28485376

Water-soluble loratadine inclusion complex: analytical control of the preparation by microwave irradiation.

PubMed

Nacsa, A; Ambrus, R; Berkesi, O; Szabó-Révész, P; Aigner, Z

2008-11-04

The majority of active pharmaceutical ingredients are poorly soluble in water. The rate-determining step of absorption is the dissolution of these drugs. Inclusion complexation with cyclodextrin derivatives can lead to improved aqueous solubility and bioavailability of pharmacons due to the formation of co-crystals through hydrogen-bonding between the components. Inclusion complexes of loratadine were prepared by a convenient new method involving microwave irradiation and the products were compared with those of a conventional preparation method. Dissolution studies demonstrated that the solubility and rate of dissolution of loratadine increased in both of the methods used. The interactions between the components were investigated by thermal analysis and Fourier Transform Infrared studies. The microwave treatment did not cause any chemical changes in the loratadine molecule.

Fast and stable algorithms for computing the principal square root of a complex matrix

NASA Technical Reports Server (NTRS)

Shieh, Leang S.; Lian, Sui R.; Mcinnis, Bayliss C.

1987-01-01

This note presents recursive algorithms that are rapidly convergent and more stable for finding the principal square root of a complex matrix. Also, the developed algorithms are utilized to derive the fast and stable matrix sign algorithms which are useful in developing applications to control system problems.

Mineral stimulation of subsurface microorganisms: release of limiting nutrients from silicates

USGS Publications Warehouse

Roger, Jennifer Roberts; Bennett, Philip C.

2004-01-01

Microorganisms play an important role in the weathering of silicate minerals in many subsurface environments, but an unanswered question is whether the mineral plays an important role in the microbial ecology. Silicate minerals often contain nutrients necessary for microbial growth, but whether the microbial community benefits from their release during weathering is unclear. In this study, we used field and laboratory approaches to investigate microbial interactions with minerals and glasses containing beneficial nutrients and metals. Field experiments from a petroleum-contaminated aquifer, where silicate weathering is substantially accelerated in the contaminated zone, revealed that phosphorus (P) and iron (Fe)-bearing silicate glasses were preferentially colonized and weathered, while glasses without these elements were typically barren of colonizing microorganisms, corroborating previous studies using feldspars. In laboratory studies, we investigated microbial weathering of silicates and the release of nutrients using a model ligand-promoted pathway. A metal-chelating organic ligand 3,4 dihydroxybenzoic acid (3,4 DHBA) was used as a source of chelated ferric iron, and a carbon source, to investigate mineral weathering rate and microbial metabolism.In the investigated aquifer, we hypothesize that microbes produce organic ligands to chelate metals, particularly Fe, for metabolic processes and also form stable complexes with Al and occasionally with Si. Further, the concentration of these ligands is apparently sufficient near an attached microorganism to destroy the silicate framework while releasing the nutrient of interest. In microcosms containing silicates and glasses with trace phosphate mineral inclusions, microbial biomass increased, indicating that the microbial community can use silicate-bound phosphate inclusions. The addition of a native microbial consortium to microcosms containing silicates or glasses with iron oxide inclusions correlated to accelerated weathering and release of Si into solution as well as the accelerated degradation of the model substrate 3,4 DHBA. We propose that silicate-bound P and Fe inclusions are bioavailable, and microorganisms may use organic ligands to dissolve the silicate matrix and access these otherwise limiting nutrients.

The adsorption of 1,3-butadiene on Pd/Ni multilayers: The interplay between spin polarization and chemisorption strength

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

Gomez, Guillermina; Belelli, Patricia G., E-mail: pbelelli@plapiqui.edu.a; Cabeza, Gabriela F.

2010-12-15

The adsorption of 1,3-butadiene (BD) on the Pd/Ni(1 1 1) multilayers has been studied using the VASP method in the framework of the density functional theory (DFT). The adsorption on two different configurations of the Pd{sub n}/Ni{sub m}(1 1 1) systems were considered. The most stable adsorption sites are dependent on the substrate composition and on the inclusion or not of spin polarization. On Pd{sub 1}Ni{sub 3}(1 1 1) surface, di-{pi}-cis and 1,2,3,4-tetra-{sigma} adsorption structures are the most stable for non-spin polarized (NSP) and spin polarized (SP) levels of calculation, respectively. Conversely, on Pd{sub 3}Ni{sub 1}(1 1 1) surface, themore » 1,2,3,4-tetra-{sigma} adsorption structure is the most stable for both NSP and SP levels, respectively. The magnetization of the Pd atoms strongly modifies the adsorption energy of BD and its most stable adsorption mode. On the other hand, as a consequence of BD adsorption, the Pd magnetization decreases. The smaller adsorption energies of BD and 1-butene on the Pd{sub 1}Ni{sub 3}(1 1 1) surface than on Pd(1 1 1) can be associated to the strained Pd overlayer deposited on Ni(1 1 1). -- Graphical Abstract: The adsorption of 1,3-butadiene on Pd/Ni(1 1 1) multilayers was theoretically studied. The most stable adsorption site depends on the substrate composition and on the inclusion of spin polarization. Display Omitted« less

Complexation of furosemide with fulvic acid extracted from shilajit: a novel approach.

PubMed

Agarwal, Suraj Prakash; Anwer, Mohammad Khalid; Aqil, Mohammad

2008-05-01

The aim of the present work was to complex furosemide (FSM) with fulvic acid (FA) extracted from shilajit with the hope of having a better understanding of the complexation behavior. The effect of FA on the aqueous solubility, dissolution rate, and permeability of FSM was investigated. Different techniques, such as grinding, freeze drying, solvent evaporation, and so forth, were used for the preparation of the complex. The complexes were prepared in molar ratios of 1:1 and 1:2 FSM:FA and were evaluated for drug inclusion, solubility, differential scanning calorimetry, Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, dissolution study, and permeation study. These methods confirm the formation of an amorphous inclusion complex of FSM with FA.

New Petrology, Mineral Chemistry and Stable MG Isotope Compositions of an Allende CAI: EK-459-7-2

NASA Technical Reports Server (NTRS)

Jeffcoat, C. R.; Kerekgyarto, A. G.; Lapen, T. J.; Righter, M.; Simon, J. I.; Ross, D. K.

2016-01-01

Calcium-aluminum-rich inclusions (CAIs) are the key to understanding physical and chemical conditions in the nascent solar nebula. These inclusions have the oldest radiometric ages of solar system materials and are composed of phases that are predicted to condense early from a gas of solar composition. Thus, their chemistry and textures record conditions and processes in the earliest stages of development of the solar nebula. Type B inclusions are typically larger and more coarse grained than other types with substantial evidence that many of them were at least partially molten. Type B inclusions are further subdivided into Type B1 (possess thick melilite mantle) and Type B2 (lack melilite mantle). Despite being extensively studied, the origin of the melilite mantles of Type B1 inclusions remains uncertain. We present petrologic and chemical data for a Type B inclusion, EK-459-7-2, that bears features found in both Type B1 and B2 inclusions and likely represents an intermediate between the two types. Detailed studies of more of these intermediate objects may help to constrain models for Type B1 rim formation.

HUNT STABLE COMPLEX LOOKING NORTHWEST TOWARD DOG KENNEL RUINS ACROSS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

HUNT STABLE COMPLEX LOOKING NORTHWEST TOWARD DOG KENNEL RUINS ACROSS THE GREAT CIRCUS - Overhills, Fort Bragg Military Reservation, Approximately 15 miles NW of Fayetteville, Overhills, Harnett County, NC

Preparation and characterization of host-guest system between inosine and β-cyclodextrin through inclusion mode

NASA Astrophysics Data System (ADS)

Prabu, Samikannu; Sivakumar, Krishnamurty; Swaminathan, Meenakshisundaram; Rajamohan, Rajaram

2015-08-01

Inosine is a nucleoside that is formed when hypoxanthine is attached to a ribose ring (also known as a ribofuranose) via a β-N9-glycosidic bond. Inosine is commonly found in tRNAs. Inosine (INS) has been used widely as an antiviral drug. The inclusion complex of INS with β-CDx in solution phase is studied by ground and excited state with UV-visible and fluorescence spectroscopy, respectively. A binding constant and stoichiometric ratio between INS and β-CDx are calculated by BH equation. The lifetime and relative amplitude of INS is increases with increasing the concentrations of β-CDx, confirms the formation of inclusion complex in liquid state. The solid complexes are prepared by kneading method (KM) and co-precipitation method (CP). The solid complex is characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), powder X-ray diffraction (XRD) and differential scanning colorimetry (DSC). CP method gives the solid product with good yield than that of physical mixture and KM method. The structure of complex is proposed based on the study of Patch - Dock server.

The preparation, characterization, and pharmacokinetic studies of chitosan nanoparticles loaded with paclitaxel/dimethyl-β-cyclodextrin inclusion complexes

PubMed Central

Ye, Ya-Jing; Wang, Yun; Lou, Kai-Yan; Chen, Yan-Zuo; Chen, Rongjun; Gao, Feng

2015-01-01

A novel biocompatible and biodegradable drug-delivery nanoparticle (NP) has been developed to minimize the severe side effects of the poorly water-soluble anticancer drug paclitaxel (PTX) for clinical use. PTX was loaded into the hydrophobic cavity of a hydrophilic cyclodextrin derivative, heptakis (2,6-di-O-methyl)-β-cyclodextrin (DM-β-CD), using an aqueous solution-stirring method followed by lyophilization. The resulting PTX/DM-β-CD inclusion complex dramatically enhanced the solubility of PTX in water and was directly incorporated into chitosan (CS) to form NPs (with a size of 323.9–407.8 nm in diameter) using an ionic gelation method. The formed NPs had a zeta potential of +15.9–23.3 mV and showed high colloidal stability. With the same weight ratio of PTX to CS of 0.7, the loading efficiency of the PTX/DM-β-CD inclusion complex-loaded CS NPs was 30.3-fold higher than that of the PTX-loaded CS NPs. Moreover, it is notable that PTX was released from the DM-β-CD/CS NPs in a sustained-release manner. The pharmacokinetic studies revealed that, compared with reference formulation (Taxol®), the PTX/DM-β-CD inclusion complex-loaded CS NPs exhibited a significant increase in AUC0→24h (the area under the plasma drug concentration–time curve over the period of 24 hours) and mean residence time by 2.7-fold and 1.4-fold, respectively. Therefore, the novel drug/DM-β-CD inclusion complex-loaded CS NPs have promising applications for the significantly improved delivery and controlled release of the poorly water-soluble drug PTX or its derivatives, thus possibly leading to enhanced therapeutic efficacy and less severe side effects. PMID:26170666

Studying anti-oxidative properties of inclusion complexes of α-lipoic acid with γ-cyclodextrin in single living fission yeast by confocal Raman microspectroscopy

NASA Astrophysics Data System (ADS)

Noothalapati, Hemanth; Ikarashi, Ryo; Iwasaki, Keita; Nishida, Tatsuro; Kaino, Tomohiro; Yoshikiyo, Keisuke; Terao, Keiji; Nakata, Daisuke; Ikuta, Naoko; Ando, Masahiro; Hamaguchi, Hiro-o.; Kawamukai, Makoto; Yamamoto, Tatsuyuki

2018-05-01

α-lipoic acid (ALA) is an essential cofactor for many enzyme complexes in aerobic metabolism, especially in mitochondria of eukaryotic cells where respiration takes place. It also has excellent anti-oxidative properties. The acid has two stereo-isomers, R- and S- lipoic acid (R-LA and S-LA), but only the R-LA has biological significance and is exclusively produced in our body. A mutant strain of fission yeast, Δdps1, cannot synthesize coenzyme Q10, which is essential during yeast respiration, leading to oxidative stress. Therefore, it shows growth delay in the minimal medium. We studied anti-oxidant properties of ALA in its free form and their inclusion complexes with γ-cyclodextrin using this mutant yeast model. Both free forms R- and S-LA as well as 1:1 inclusion complexes with γ-cyclodextrin recovered growth of Δdps1 depending on the concentration and form. However, it has no effect on the growth of wild type fission yeast strain at all. Raman microspectroscopy was employed to understand the anti-oxidant property at the molecular level. A sensitive Raman band at 1602 cm-1 was monitored with and without addition of ALAs. It was found that 0.5 mM and 1.0 mM concentrations of ALAs had similar effect in both free and inclusion forms. At 2.5 mM ALAs, free forms inhibited the growth while inclusion complexes helped in recovered. 5.0 mM ALA showed inhibitory effect irrespective of form. Our results suggest that the Raman band at 1602 cm-1 is a good measure of oxidative stress in fission yeast.

Improving the toughness of ultrahigh strength steel

NASA Astrophysics Data System (ADS)

Sato, Koji

2002-01-01

The ideal structural steel combines high strength with high fracture toughness. This dissertation discusses the toughening mechanism of the Fe/Co/Ni/Cr/Mo/C steel, AerMet 100, which has the highest toughness/strength combination among all commercial ultrahigh strength steels. The possibility of improving the toughness of this steel was examined by considering several relevant factors. Chapter 1 reviews the mechanical properties of ultrahigh strength steels and the physical metallurgy of AerMet 100. It also describes the fracture mechanisms of steel, i.e. ductile microvoid coalescence, brittle transgranular cleavage, and intergranular separation. Chapter 2 examines the strength-toughness relationship for three heats of AerMet 100. A wide variation of toughness is obtained at the same strength level. The toughness varies despite the fact that all heat fracture in the ductile fracture mode. The difference originates from the inclusion content. Lower inclusion volume fraction and larger inclusion spacing gives rise to a greater void growth factor and subsequently a higher fracture toughness. The fracture toughness value, JIc, is proportional to the particle spacing of the large non-metallic inclusions. Chapter 3 examines the ductile-brittle transition of AerMet 100 and the effect of a higher austenitization temperature, using the Charpy V-notch test. The standard heat treatment condition of AerMet 100 shows a gradual ductile-brittle transition due to its fine effective grain size. Austenitization at higher temperature increases the prior austenite grain size and packet size, leading to a steeper transition at a higher temperature. Both transgranular cleavage and intergranular separation are observed in the brittle fracture mode. Chapter 4 examines the effect of inclusion content, prior austenite grain size, and the amount of austenite on the strength-toughness relationship. The highest toughness is achieved by low inclusion content, small prior austenite grain size, and a small content of stable austenite. The low inclusion content increases the strain at the fracture. The reduction in prior austenite grain size prevents the fast unstable crack propagation by cleavage. And the stable austenite decreases the strength of the intergranular separation at the prior austenite grain boundary, which provides the stress relief at the crack tip.

Inclusions in freely suspended smectic films

NASA Astrophysics Data System (ADS)

Stannarius, Ralf; Harth, Kirsten

Smectic liquid crystal phases have a unique property: Like soap solutions, they can form stable freely suspended films. Their aspect ratios can be larger than one million to one. Such films can serve as models for two-dimensional (2D) uids, with or without in-plane anisotropy. Solid or liquid inclusions trapped in these films by capillary forces can move in the film plane and interact with other inclusions, with film thickness gradients or the film boundaries, and even with the local orientation field. We describe preparation techniques to incorporate particles or droplets in thin smectic films, and optical observation methods. Several aspects make inclusions in freely suspended films interesting research objects: They provide rich information on capillary forces as well as surface and interfacial tensions, they can serve as platforms for hydrodynamic studies in 2D, and they may help to understand coalescence dynamics at the transition from 2D to 3D...

A stable compound of helium and sodium at high pressure

DOE PAGES

Dong, Xiao; Oganov, Artem R.; Goncharov, Alexander F.; ...

2017-02-06

Helium is generally understood to be chemically inert and this is due to its extremely stable closed-shell electronic configuration, zero electron affinity and an unsurpassed ionization potential. It is not known to form thermodynamically stable compounds, except a few inclusion compounds. Here, using the ab initio evolutionary algorithm USPEX and subsequent high-pressure synthesis in a diamond anvil cell, we report the discovery of a thermodynamically stable compound of helium and sodium, Na 2He, which has a fluorite-type structure and is stable at pressures >113 GPa. We show that the presence of He atoms causes strong electron localization and makes thismore » material insulating. This phase is an electride, with electron pairs localized in interstices, forming eight-centre two-electron bonds within empty Na 8 cubes. As a result, we also predict the existence of Na 2HeO with a similar structure at pressures above 15 GPa.« less

A stable compound of helium and sodium at high pressure

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

Dong, Xiao; Oganov, Artem R.; Goncharov, Alexander F.

Helium is generally understood to be chemically inert and this is due to its extremely stable closed-shell electronic configuration, zero electron affinity and an unsurpassed ionization potential. It is not known to form thermodynamically stable compounds, except a few inclusion compounds. Here, using the ab initio evolutionary algorithm USPEX and subsequent high-pressure synthesis in a diamond anvil cell, we report the discovery of a thermodynamically stable compound of helium and sodium, Na 2He, which has a fluorite-type structure and is stable at pressures >113 GPa. We show that the presence of He atoms causes strong electron localization and makes thismore » material insulating. This phase is an electride, with electron pairs localized in interstices, forming eight-centre two-electron bonds within empty Na 8 cubes. We also predict the existence of Na 2HeO with a similar structure at pressures above 15 GPa.« less

A stable compound of helium and sodium at high pressure

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

Dong, Xiao; Oganov, Artem R.; Goncharov, Alexander F.

Helium is generally understood to be chemically inert and this is due to its extremely stable closed-shell electronic configuration, zero electron affinity and an unsurpassed ionization potential. It is not known to form thermodynamically stable compounds, except a few inclusion compounds. Here, using the ab initio evolutionary algorithm USPEX and subsequent high-pressure synthesis in a diamond anvil cell, we report the discovery of a thermodynamically stable compound of helium and sodium, Na 2He, which has a fluorite-type structure and is stable at pressures >113 GPa. We show that the presence of He atoms causes strong electron localization and makes thismore » material insulating. This phase is an electride, with electron pairs localized in interstices, forming eight-centre two-electron bonds within empty Na 8 cubes. As a result, we also predict the existence of Na 2HeO with a similar structure at pressures above 15 GPa.« less

Analytical techniques for characterization of cyclodextrin complexes in aqueous solution: a review.

PubMed

Mura, Paola

2014-12-01

Cyclodextrins are cyclic oligosaccharides endowed with a hydrophilic outer surface and a hydrophobic inner cavity, able to form inclusion complexes with a wide variety of guest molecules, positively affecting their physicochemical properties. In particular, in the pharmaceutical field, cyclodextrin complexation is mainly used to increase the aqueous solubility and dissolution rate of poorly soluble drugs, and to enhance their bioavailability and stability. Analytical characterization of host-guest interactions is of fundamental importance for fully exploiting the potential benefits of complexation, helping in selection of the most appropriate cyclodextrin. The assessment of the actual formation of a drug-cyclodextrin inclusion complex and its full characterization is not a simple task and often requires the use of different analytical methods, whose results have to be combined and examined together. The purpose of the present review is to give, as much as possible, a general overview of the main analytical tools which can be employed for the characterization of drug-cyclodextrin inclusion complexes in solution, with emphasis on their respective potential merits, disadvantages and limits. Further, the applicability of each examined technique is illustrated and discussed by specific examples from literature. Copyright © 2014 Elsevier B.V. All rights reserved.

A pH-independent instantaneous release of flurbiprofen: a study of the preparation of complexes, their characterization and in vitro/in vivo evaluation.

PubMed

Wang, Han-Bing; Yang, Fei-Fei; Gai, Xiu-Mei; Cheng, Bing-Chao; Li, Jin-Yu; Pan, Hao; Yang, Xing-Gang; Pan, Wei-San

2017-09-01

In this study, furbiprofen/hydroxypropyl-β-cyclodextrin (HPβCD) inclusion complexes were prepared to improve the drug dissolution and facilitate its application in hydrophilic gels. Inclusion complexes were prepared using a supercritical fluid processing and a conventional optimized co-lypholization method was employed as a reference. The entrapment efficacy and drug loading of both methods were investigated. Evaluation of drug dissolution enhancement was conducted in deionized water as well as buffer solutions of different pH. Carbopol 940 gels of both flurbiprofen and flurbiprofen/HPβCD inclusion complexes, with or without penetration enhancers, were prepared and percutaneous permeation studies were performed using rat abdominal skin samples. Formation of flurbiprofen/HPβCD inclusion complexes was confirmed by Fourier transform-infrared spectroscopy, differential scanning calorimetry, X-ray diffraction and scanning electron microscopy. The results obtained showed that SCF processing produced a higher EE (81.91 ± 1.54%) and DL (6.96 ± 0.17%) compared with OCL with values of 69.11 ± 2.23% and 4.00 ± 1.01%, respectively. A marked instantaneous release of flurbiprofen/HPβCD inclusion complexes prepared by SCF processing (103.04 ± 2.66% cumulative release within 5 min, a 10-fold increase in comparison with flurbiprofen alone) was observed. In addition, this improvement in dissolution was shown to be pH-independent (the percentage cumulative release at pH 1.2, 4.5, 6.8 and 7.4 at 5 min was 95.19 ± 1.71, 101.75 ± 1.44, 105.37 ± 4.58 and 96.84 ± 0.56, respectively). Percutaneous permeability of flurbiprofen-in-HPβCD-in-gels could be significantly accelerated by turpentine oil and was related to the water content in the system. An in vivo pharmacokinetic study showed a 2-fold increase in C max and a shortened T max as well as a comparable relative bioavailability when compared with the commercial flurbiprofen Cataplasms (Zepolas ® ). With their superior dissolution, these flurbiprofen/HPβCD inclusion complexes prepared by SCF processing could provide improved applications for flurbiprofen.

Content determination of aniracetam in aniracetam inclusion complex by HPLC.

PubMed

Li, Yongjian; Hu, Dejian; Sun, Yong

2009-01-01

We established a HPLC method for content determination of aniracetam in aniracetam inclusion complex. The chromato column was Agilent ODS (4.6mm x 150mm, 5 microm), the mobile phase was methanol-0.01 mol/L Potassium dihydrogen phosphate buffer solution (25:75, pH 3.0), with the flow rate of 1.0 ml/min, column temperature of 30 degrees and the detection wave at 280 nm, the sample size was 20microL. A good linear relationship was obtained between the peak areas and the concentrations of aniracetam in the range from 5- 80microg/ml (r=0.9998), the mean recovery was 100.1% (n=15), RSD=0.19%. This method is convenient, rapid, accurate, and brings about good recovery; it can be used for content determination of aniracetam in aniracetam inclusion complex.

Signal enhancement of carboxylic acids by inclusion with β-cyclodextrin in negative high-voltage-assisted laser desorption ionization mass spectrometry.

PubMed

Ren, Xinxin; Liu, Jia; Zhang, Chengsen; Sun, Jiamu; Luo, Hai

2014-01-15

It is difficult to directly analyze carboxylic acids in complex mixtures by ambient high-voltage-assisted laser desorption ionization mass spectrometry (HALDI-MS) in negative ion mode due to the low ionization efficiency of carboxylic acids. A method for the rapid detection of carboxylic acids in negative HALDI-MS has been developed based on their inclusion with β-cyclodextrin (β-CD). The negative HALDI-MS signal-to-noise ratios (S/Ns) of aliphatic, aromatic and hetero atom-containing carboxylic acids can all be significantly improved by forming 1:1 complexes with β-CD. These complexes are mainly formed by specific inclusion interactions which are verified by their collision-induced dissociation behaviors in comparison with that of their corresponding maltoheptaose complexes. A HALDI-MS/MS method has been successfully developed for the detection of α-lipoic acid in complex cosmetics and ibuprofen in a viscous drug suspension. The negative HALDI-MS S/Ns of carboxylic acids can be improved up to 30 times via forming non-covalent complexes with β-CD. The developed method shows the advantages of being rapid and simple, and is promising for rapid detection of active ingredients in complex samples or fast screening of drugs and cosmetics. Copyright © 2013 John Wiley & Sons, Ltd.

Peripheral substitution of pheophorbides and bacteriopheophorbides to promote inclusion into inert carrier systems for PDT

NASA Astrophysics Data System (ADS)

Roehrs, Susanne; Ruebner-Heuermann, Anja; Hartwich, G.; Scheer, H.; Moser, Joerg G.

1996-01-01

Pheophorbide a ethyl ester, pyropheophorbide a ethyl ester, and bacteriopheophorbide ethyl ester were substituted in 31-position with tert.butyl phenoxy or tert.butyl benzoic acid ester groups resp. in order to enhance affinity to (beta) -cyclodextrin dimers which form inclusion complexes with these photosensitizing drugs. This is a first step to construct inert transport complexes in order to photosensitize specifically cancer cells.

Inclusion Complexes Behavior at the Air-Water Interface. Molecular Dynamic Simulation Study.

NASA Astrophysics Data System (ADS)

Gargallo, L.; Vargas, D.; Sandoval, C.; Saavedra, M.; Becerra, N.; Leiva, A.; Radić, D.

2008-08-01

The interfacial properties of the inclusion complexes (ICs), obtained from the threading of α-cyclodextrin (α-CD) onto poly(ethylene-oxide)(PEO), poly(ɛ-caprolactone)(PEC) and poly(tetrahydrofuran)(PTHF) and their precursor homopolymers (PHPoly), were studied at the air-water interface. The free surface energy was determined by wettability measurements. The experimental behavior of these systems was described by an atomistic molecular dynamics simulation (MDS).

Including Students with Moderate and Severe Complexity of Disability in Kindergarten and First Grade: Investigating the Relationship between Inclusive Classroom Quality Indicators, Level of Inclusive Education, and Social Competence

ERIC Educational Resources Information Center

Matz, Amy Kristen

2013-01-01

The development of social competence for children is critical to their ability to navigate social decision making processes; however, children with complex disabilities have many difficulties in developing social competence. In an educational environment, the optimal setting for a child to develop social competence is within the inclusive…

Laboratory Study on Prevention of CaO-Containing ASTM "D-Type" Inclusions in Al-Deoxidized Low-Oxygen Steel Melts During Basic Slag Refining

NASA Astrophysics Data System (ADS)

Jiang, Min; Wang, Xin-Hua; Yang, Die; Lei, Shao-Long; Wang, Kun-Peng

2015-12-01

Present work was attempted to explore the possibility of preventing CaO-containing inclusions in Al-deoxidized low-oxygen special steel during basic slag refining, which were known as ASTM D-type inclusions. Based on the analysis on formation thermodynamics of CaO-containing inclusions, a series of laboratory experiments were designed and carried out in a vacuum induction furnace. During the experiments, slag/steel reaction equilibrium was intentionally suppressed with the aim to decrease the CaO contents in inclusions, which is different from ordinary concept that slag/steel reaction should be promoted for better control of inclusions. The obtained results showed that high cleanliness of steel was obtained in all the steel melts, with total oxygen contents varied between 0.0003 and 0.0010 pct. Simultaneously, formation of CaO-containing inclusions was successfully prohibited, and all the formed oxide inclusions were MgO-Al2O3 or/and Al2O3 in very small sizes of about 1 to 3 μm. And 90 pct to nearly 98 pct of them were wrapped by relative thicker MnS outer surface layers to produce dual-phased "(MgO-Al2O3) + MnS" or "Al2O3 + MnS" complex inclusions. Because of much better ductility of MnS, certain deformability of these complex inclusions can be expected which is helpful to improve fatigue resistance property of steel. Only very limited number of singular MnS inclusions were with sizes larger than 13 μm, which were formed during solidification because of. In the end, formation of oxide inclusions in steel was qualitatively evaluated and discussed.

Creating an inclusive mall environment with the PRECEDE-PROCEED model: a living lab case study.

PubMed

Ahmed, Sara; Swaine, Bonnie; Milot, Marc; Gaudet, Caroline; Poldma, Tiiu; Bartlett, Gillian; Mazer, Barbara; Le Dorze, Guylaine; Barbic, Skye; Rodriguez, Ana Maria; Lefebvre, Hélène; Archambault, Philippe; Kairy, Dahlia; Fung, Joyce; Labbé, Delphine; Lamontagne, Anouk; Kehayia, Eva

2017-10-01

Although public environments provide opportunities for participation and social inclusion, they are not always inclusive spaces and may not accommodate the wide diversity of people. The Rehabilitation Living Lab in the Mall is a unique, interdisciplinary, and multi-sectoral research project with an aim to transform a shopping complex in Montreal, Canada, into an inclusive environment optimizing the participation and social inclusion of all people. The PRECEDE-PROCEDE Model (PPM), a community-oriented and participatory planning model, was applied as a framework. The PPM is comprised of nine steps divided between planning, implementation, and evaluation. The PPM is well suited as a framework for the development of an inclusive mall. Its ecological approach considers the environment, as well as the social and individual factors relating to mall users' needs and expectations. Transforming a mall to be more inclusive is a complex process involving many stakeholders. The PPM allows the synthesis of several sources of information, as well as the identification and prioritization of key issues to address. The PPM also helps to frame and drive the implementation and evaluate the components of the project. This knowledge can help others interested in using the PPM to create similar enabling and inclusive environments world-wide. Implication for rehabilitation While public environments provide opportunities for participation and social inclusion, they are not always inclusive spaces and may not accommodate the wide diversity of people. The PRECEDE PROCEDE Model (PPM) is well suited as a framework for the development, implementation, and evaluation of an inclusive mall. Environmental barriers can negatively impact the rehabilitation process by impeding the restoration and augmentation of function. Removing barriers to social participation and independent living by improving inclusivity in the mall and other environments positively impacts the lives of people with disabilities.

Study on the inclusion behavior of p-sulfonatocalix[6]arene with propranolol by spectrofluorometry

NASA Astrophysics Data System (ADS)

Li, Hui; Song, Jin-Ping; Chao, Jian-Bin; Shuang, Shao-Min; Dong, Chuan

2012-11-01

The inclusion interaction between propranolol (PPL) and p-sulfonatocalix[6]arene (SCX6) was investigated by fluorescence and 1H NMR spectroscopy. Influences of pH, temperature, ionic strength and the concentration of SCX6 were examined in detail. In phosphate buffer solution with pH 7.5, the fluorescence of PPL dramatically quenched upon addition of SCX6 revealing the formation of inclusion complexes between PPL and SCX6. The stoichiometric ratio was verified to be 1:1 by the continuous variation method. The inclusion constant of PPL-SCX6 complexes was calculated as 2.2 × 104 L/mol by the nonlinear curve fitting method. 1H NMR titration spectra testified that the aliphatic chain of PPL may be partially penetrated into the hydrophobic cavity of SCX6. This was confirmed by molecular dynamics calculations.

Spectral characteristics of tramadol in different solvents and β-cyclodextrin

NASA Astrophysics Data System (ADS)

Anton Smith, A.; Manavalan, R.; Kannan, K.; Rajendiran, N.

2009-10-01

Effect of solvents and β-cyclodextrin on the absorption and fluorescence spectra of tramadol drug has been investigated and compared with anisole. The solid inclusion complex of tramadol with β-CD is investigated by FT-IR, 1H NMR, scanning electron microscope (SEM), DSC and semiempirical methods. The thermodynamic parameter (Δ G) of inclusion process is determined. A solvent study shows (i) the spectral behaviour of both tramadol and anisole molecules is similar to each other and (ii) the cyclohexanol group in tramadol is not effectively conjugated with anisole group. However, in β-CD, due to space restriction of the CD cavity, a weak interaction is present between the above groups in tramadol. β-Cyclodextrin studies show that tramadol forms 1:2 inclusion complex with β-CD. A mechanism is proposed for the inclusion process.

Letter Report: Stable Hydrogen and Oxygen Isotope Analysis of B-Complex Groundwater Samples

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

Lee, Brady D.; Moran, James J.; Nims, Megan K.

Report summarizing stable oxygen and hydrogen isotope analysis of two groundwater samples from the B-Complex. Results from analyses were compared to perched water and pore water analyses performed previously.

Sparkle model for AM1 calculation of lanthanide complexes: improved parameters for europium.

PubMed

Rocha, Gerd B; Freire, Ricardo O; Da Costa, Nivan B; De Sá, Gilberto F; Simas, Alfredo M

2004-04-05

In the present work, we sought to improve our sparkle model for the calculation of lanthanide complexes, SMLC,in various ways: (i) inclusion of the europium atomic mass, (ii) reparametrization of the model within AM1 from a new response function including all distances of the coordination polyhedron for tris(acetylacetonate)(1,10-phenanthroline) europium(III), (iii) implementation of the model in the software package MOPAC93r2, and (iv) inclusion of spherical Gaussian functions in the expression which computes the core-core repulsion energy. The parametrization results indicate that SMLC II is superior to the previous version of the model because Gaussian functions proved essential if one requires a better description of the geometries of the complexes. In order to validate our parametrization, we carried out calculations on 96 europium(III) complexes, selected from Cambridge Structural Database 2003, and compared our predicted ground state geometries with the experimental ones. Our results show that this new parametrization of the SMLC model, with the inclusion of spherical Gaussian functions in the core-core repulsion energy, is better capable of predicting the Eu-ligand distances than the previous version. The unsigned mean error for all interatomic distances Eu-L, in all 96 complexes, which, for the original SMLC is 0.3564 A, is lowered to 0.1993 A when the model was parametrized with the inclusion of two Gaussian functions. Our results also indicate that this model is more applicable to europium complexes with beta-diketone ligands. As such, we conclude that this improved model can be considered a powerful tool for the study of lanthanide complexes and their applications, such as the modeling of light conversion molecular devices.

Enacting Understanding of Inclusion in Complex Contexts: Classroom Practices of South African Teachers

ERIC Educational Resources Information Center

Engelbrecht, Petra; Nel, Mirna; Nel, Norma; Tlale, Dan

2015-01-01

While the practice of inclusive education has recently been widely embraced as an ideal model for education, the acceptance of inclusive education practices has not translated into reality in most mainstream classrooms. Despite the fact that education policies in South Africa stipulate that all learners should be provided with the opportunities to…

A combined molecular dynamics simulation and quantum mechanics study on mercaptopurine interaction with the cucurbit [6,7] urils: Analysis of electronic structure.

PubMed

Zaboli, Maryam; Raissi, Heidar

2018-01-05

In the current study, the probability of complex formation between mercaptopurine drug with cucurbit[6]urils and cucurbit[7]urils has been investigated. The calculations for geometry optimization of complexes have been carried out by means of DFT (B3LYP), DFT-D (B3LYP-D) and M06-2X methods. The Atoms In Molecules (AIM), Natural Bond Orbital (NBO), NMR, the density of states (DOSs) and frontier molecular orbital (MO) analyses have been done on the inclusion complexes. In addition, the UV-Vis spectra of the first eight states have been obtained by CAM-B3LYP/TD-DFT calculation. The obtained results of the complexation process reveal that CB[7]-DRG complexes are more favorable than that of CB[6]-DRG interactions. Furthermore, our theoretical results show that configurations III and I are the most stable configurations related to the CB[6]/DRG and CB[7]/DRG interactions, respectively. The positive ∇ 2 ρ (r) and HC values at the bond critical points indicate that exist the weak H-bonds between CB[6] and CB[7] with H atoms of the drug molecule. The obtained negative binding energy values of CB[7]-DRG interaction in solution phase show the stability of these complexes in the aqueous medium. Also, all of the observed parameters of molecular dynamics simulation such as the number of contacts, hydrogen bonding, center-of-mass distance and van der Waals energy values confirm the encapsulation of mercaptopurine molecule inside the cucurbit[7]urils cavity at about 3.2ns. Copyright © 2017 Elsevier B.V. All rights reserved.

Polynuclear Aromatic Hydrocarbons with Curved Surfaces: Buckyballs

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

Sygula, Andrzej

The discovery of a new allotropic form of elemental carbon – the fullerenes – and subsequently other novel forms of elemental carbon with pyramidalized surfaces, most notably single-walled and multi-walled carbon nanotubes, introduced a novel structural motif to the polycyclic aromatic hydrocarbons (PAHs) with nonplanar surfaces. Our research program supported by BES DOE grant DE-FG02-04ER15514 has dealt with the synthesis, structural studies, and chemistry of the novel curved-surface PAHs with carbon frameworks structurally related to fullerenes. They are referred to as “buckybowls”. We prepared several new buckybowls and, even more importantly, developed the efficient, gram-scale synthetic methodologies for the preparationmore » of small buckybowls, most notably corannulene (C20H10) and its derivatives. In addition, the employment of the corannulene-based synthons previously developed in our laboratory led to a number of highly nonplanar molecular architectures with two or more corannulene subunits with a potential for the applications as novel materials in separation sciences, nanoelectronics, photovoltaics and catalysis. In collaboration with Professor Angelici (Iowa State) we prepared and characterized several transition metal complexes of corannulene, providing the first structural characterization of η6 metal complexes of buckybowls by a single crystal X-ray diffraction. In addition to the definitive structural characterization of the complexes we demonstrated that the (η6-C6Me6)Ru2+ unit in some relatively stable complexes activate the corannulene ligand to react with proper nucleophiles suggesting that such complexex may be used in catalysis. (Section C). We have explored the efficiency of the dispersion-based interactions of curved-surface conjugated carbon networks by high-level computational models. We showed that the curvature of such networks does not reduce the van der Waals attractions as compared to the planar systems of similar size. We than concentrated on the design, synthesis and testing of the previously unknown molecular receptors with corannulene pincers which are capable of forming the strong ball-and-socket inclusion complexes with fullerenes in solution and in the solid state. Buckycatcher I (a molecular receptor with two corannulene pincers preorganized on a tetrabensocyclooctatetraene tether) inclusion complexes with fullerenes provided the first experimental evidence for the importance of concave-convex π – π interactions in the supramolecular chemistry of fullerene carbon cages with buckybowls. C60@Buckycatcher I has become the prototypical supramolecular system formed by the relatively weak (on the atom-to-atom bases) and has been extensively used by the computational community to test the quality of the theoretical models. In addition, Buckycatcher I shows an exceptional ability to adopt other guest molecules and several its inclusion complexes and/or solvates have been structurally characterized. These unusual structures show the potential of the buckycatchers to be tested as novel organic materials. “Intelligent design” of molecular receptors with corannulene receptors using computational approach allowing for a priori prediction of their binding potentials led to the preparation of other buckycatchers. Both bi- and tridentate corannulene pincers were tested and two of the bidentate receptors (Buckycatchers II and III) exhibited the outstanding affinity toward fullerenes, significantly exciding Buckycatcher I performance. Careful tailoring of the tethers resulted in the optimization of binding energies of the receptors with guest carbon cages and in the reduction of the entropy/solvation penalties. Practical preparation of dicorannulenopentacene opens a new avenue for the synthesis of a pool of bis-corannulene receptors possessing polar groups on their dibenzobarrelene tether. The polar “anchors” can be used to attach these efficient fullerene receptors to solid supports in order to modify their surfaces with the potential applications in separation sciences, catalysis and photovoltaic materials. additionally, the presence of such groups will improve the solubility of the receptors in polar solvents, expanding the scope of their supramolecular chemistry in solutions. Rigorous studies of thermodynamics of host-guest association of molecular clips and tweezers in organic solvents with C60/C70 inclusion complexes with Buckycatcher I as a model system have provided a full set of thermodynamical data including ΔG, ΔH, and –TΔS, for the formation of the inclusion complexes over a range of temperatures and in several solvents. Both 1H NMR and Isothermal Calorimetry (ITC) titrations provide virtually identical association constants, confirming the reliability of the results. WE have shown that thermodynamics of the host-guest complex formation is more complicated than anticipated and proposed by the existing computational models. These data are of premium importance for the testing of the computational solvation models and for a deeper understanding of the supramolecular interactions in organic solvents.« less

Solutions for Dynamic Variants of Eshelby's Inclusion Problem

NASA Astrophysics Data System (ADS)

Michelitsch, Thomas M.; Askes, Harm; Wang, Jizeng; Levin, Valery M.

The dynamic variant of Eshelby's inclusion problem plays a crucial role in many areas of mechanics and theoretical physics. Because of its mathematical complexity, dynamic variants of the inclusion problems so far are only little touched. In this paper we derive solutions for dynamic variants of the Eshelby inclusion problem for arbitrary scalar source densities of the eigenstrain. We study a series of examples of Eshelby problems which are of interest for applications in materials sciences, such as for instance cubic and prismatic inclusions. The method which covers both the time and frequency domain is especially useful for dynamically transforming inclusions of any shape.

Preparation, characterization and in vivo evaluation of formulation of repaglinide with hydroxypropyl-β-cyclodextrin.

PubMed

Liu, Meina; Cao, Wen; Sun, Yinghua; He, Zhonggui

2014-12-30

The therapeutic efficacy of repaglinide (RPG) is limited by the low and variable oral bioavailability owing to its limited aqueous solubility. In our present study, the development and evaluation of inclusion complex applying hydroxypropyl-β-cyclodextrin (HP-β-CD) for the improvement of oral bioavailability of repaglinide was investigated systematically. The inclusion complex of repaglinide was prepared by lyophilization technique using drug: hydroxypropyl-β-cyclodextrin (1:15 mole). The prepared complexation was characterized by differential scanning calorimetry (DSC), X-ray diffractometry (XRD), NMR spectroscopy and evaluated by dissolution studies. The (1)H NMR was used in the structure study of repaglinide-HP-β-CD (RPG-HP-β-CD) inclusion complex. The analysis proved the higher probability of the repaglinide A-ring into the narrow rim of the β-cyclodextrin molecule. All the characterization information confirmed the formation of RPG-HP-β-CD inclusion complex. The in vivo pharmacokinetics of RPG-HP-β-CD and their physical mixture were performed in beagle dogs. For the first time, a simple, rapid, and sensitive LC-MS/MS method for determination of RPG in beagle dog plasma was developed. The Cmax and AUC0-t of RPG-HP-β-CD were 2.5 and 2 times higher than that of the physical mixture. These results suggested that the interaction of repaglinide with HP-β-CD could notably improve the dissolution rate and bioavailability of repaglinide comparing with its physical mixture. Copyright © 2014 Elsevier B.V. All rights reserved.

Stable powders made from photosensitive polycrystalline complexes of heterocyclic monomers and their polymers

NASA Technical Reports Server (NTRS)

Murphy, Oliver J. (Inventor); Hitchens, G. Duncan (Inventor); Hodko, Dalibor (Inventor)

1999-01-01

The present invention relates to a low electronic conductivity polymer composition having well dispersed metal granules, a stable powder made from photosensitive polycrystalline complexes of pyrrole, or its substituted derivatives and silver cations for making the polymer composition, and methods of forming the stable powder and polymer composition, respectively. A polycrystalline complex of silver and a monomer, such as pyrrole, its substituted derivatives or combinations thereof, is precipitated in the form of a stable photosensitive powder upon addition of the monomer to a solvent solution, such as toluene containing an electron acceptor. The photosensitive powder can be stored in the dark until needed. The powder may be dissolved in a solvent, cast onto a substrate and photopolymerized.

Cyclodextrins: A Weapon in the Fight Against Antimicrobial Resistance

NASA Astrophysics Data System (ADS)

Wong, Chew Ee; Dolzhenko, Anton V.; Lee, Sui Mae; Young, David James

Antimicrobial resistance poses one of the most serious global challenges of our age. Cyclodextrins (CDs) are widely utilized excipients in formulations because of their solubilizing properties, low toxicity, and low inflammatory response. This review summarizes recent investigations of antimicrobial agents involving CDs and CD-based antimicrobial materials. CDs have been employed for antimicrobial applications either through formation of inclusion complexes or by chemical modification of their hydroxyl groups to tailor pharmaceutically active compounds. Applications of these CD inclusion complexes include drug delivery, antimicrobial coatings on materials (e.g., biomedical devices and implants) and antimicrobial dressings that help to prevent wound infections. There are relatively limited studies of chemically modified CDs with antimicrobial activity. The mechanism of action of antimicrobial CD inclusion complexes and derivatives needs further elucidation, but activity of CDs and their derivatives is often associated with their interaction with bacterial cell membranes.

Recovery and purification of cholesterol from cholesterol-β-cyclodextrin inclusion complex using ultrasound-assisted extraction.

PubMed

Li, Yong; Chen, Youliang; Li, Hua

2017-01-01

Response surface methodology was used to optimize ultrasound-assisted ethanol extraction (UAE) of cholesterol from cholesterol-β-cyclodextrin (C-β-CD) inclusion complex prepared from duck yolk oil. The best extraction conditions were solvent-solid ratio 10mL/g, ultrasonic power 251W, extraction temperature 56°C and sonication time 36min. Under these conditions, the highest cholesterol extraction yield and cholesterol content obtained 98.12±0.25% and 43.38±0.61mg/g inclusion complex, respectively. As compared with Reflux extraction and Soxhlet extraction, the UAE was more efficient and economical. To increase the purity of crude cholesterol extraction, silica gel column chromatography and crystallization were carried out. Finally, cholesterol was obtained at 95.1% purity, 71.7% recovery and 22.0% yield. Copyright © 2016 Elsevier B.V. All rights reserved.

Host-guest interaction between pinocembrin and cyclodextrins: Characterization, solubilization and stability

NASA Astrophysics Data System (ADS)

Zhou, Shu-Ya; Ma, Shui-Xian; Cheng, Hui-Lin; Yang, Li-Juan; Chen, Wen; Yin, Yan-Qing; Shi, Yi-Min; Yang, Xiao-Dong

2014-01-01

The inclusion complexation behavior, characterization and binding ability of pinocembrin with β-cyclodextrin (β-CD) and its derivative 2-hydroxypropyl-β-cyclodextrin (HPβCD) were investigated in both solution and the solid state by means of XRD, DSC, 1H and 2D NMR and UV-vis spectroscopy. The results showed that the water solubility and thermal stability of pinocembrin were obviously increased in the inclusion complex with cyclodextrins. This satisfactory water solubility and high stability of the pinocembrin/CD complexes will be potentially useful for their application as herbal medicines or healthcare products.

Transmetallation from CCC-NHC pincer Zr complexes in the synthesis of air-stable CCC-NHC pincer Co(iii) complexes and initial hydroboration trials.

PubMed

Reilly, Sean W; Webster, Charles Edwin; Hollis, T Keith; Valle, Henry U

2016-02-21

Development of CCC-NHC pincer Co complexes via transmetalation from Zr is reported. Formation of these air-stable Co(iii) complexes was achieved through use of a CoCl2 or Co(acac)3in situ or with a discrete CCC-NHC pincer Zr transmetallating agent. Preliminary activity in the hydroboration of styrene is reported. This facile methodology will further the development of CCC-NHC pincer first-row transition metal complexes.

Social Exclusion, Social Inclusion and "Passing": The Experiences of Dalit Students at One Elite Indian University

ERIC Educational Resources Information Center

Ovichegan, Samson

2014-01-01

The purpose of this paper is twofold; first the paper explores and describes the complex ways in which social exclusion can (sometimes) be reconstituted within policy attempts at social inclusion: the quota policy in India. Second, the paper provides a grounded account of the connectedness of inclusion/exclusion and an illustration of how those…

"Where Is _______?": Culture and the Process of Change in the Development of Inclusive Schools

ERIC Educational Resources Information Center

McMaster, Christopher

2015-01-01

The modern school is a multi-layered and complex institution. For inclusive values and practices to embed in educational systems the nature of school culture and the change process must be considered. Qualitative data was gathered during a year-long ethnographic study of inclusive change in a co-educational high school. This paper applies a model…

Pre-eruptive storage conditions and continuous decompression relations of rhyodacite magma erupted from Chaos Crags, Lassen Volcanic Center, California

NASA Astrophysics Data System (ADS)

Quinn, E. T.; Andrews, B. J.; Schwab, B. E.; Clynne, M. A.

2013-12-01

We performed a series of hydrothermal (high-temperature and -pressure) phase equilibrium experiments on a natural rhyodacite pumice from the 1103 ×13 years BP pyroclastic flow from the Chaos Crags, Lassen Volcanic Center, California. The pumice (LQ13-01, collected at the same location as LC84-417 (69.58 wt. % SiO2) by Clynne) is from the lower pyroclastic flow member of the group 1 lavas, the most silicic products known of Chaos Crags. Group 1 lavas are homogeneous (69-70 wt. % SiO2), petrographically and compositionally similar with rare to sparse mafic inclusions, and comprise the earliest emplaced units of Chaos Crags, the lower, middle, and upper pyroclastic flows, and domes A and B, whereas group 2 are comparatively heterogeneous (67-69 wt. % SiO2), with increasing abundance (10-15%) of mafic inclusions throughout the emplacement sequence, and comprise domes C through F. The phase assemblage in the natural sample used as experimental starting material comprises phenocrysts of quartz, plagioclase feldspars with rims of ~An35, biotite, hornblende, and Fe-Ti oxides in a vesiculated glassy matrix. Trace mafic enclaves are also present, but were removed from experimental starting material. All experiments were performed at the Smithsonian Institution. Experiments were run under H2O-saturated conditions at pressures of 75 MPa to 200 MPa and temperatures of 750°C to 900°C, at oxygen fugacity NNO+1 (×0.5-log-units), for 93 to 132 hours. EPMA and SEM analyses of experimental products show quartz is stable from <200 MPa at 750°C to <150 MPa at 800°C and is not stable at temperatures >800°C, within the investigated range. Amphibole is stable from >75 MPa at 750°C to >100 MPa at 800°C to 200 MPa at <850°C, and is not stable ≤75 MPa or ≥850°C. Biotite is stable at <800°C at 75 MPa to <825°C at 200 MPa, and not stable for any pressure at ≥850°C. Pyroxene, not present in the starting material is stable for 200MPa at >775°C and all pressures at temperatures ≥825°C, within the investigated range. FTIR analysis of quartz-hosted melt inclusions contain 4.0-5.0 wt. % H2O (average 4.3 wt. %), suggesting saturation pressures of 100-110 MPa (calculated using model of Papale et al., 2006). Comparison of the natural samples with the experimentally determined phase diagram and melt inclusions, suggests pre-eruptive storage conditions of 110-125 MPa and 775°C; given FeTi-oxide temperatures of 850 °C, magma may have been heated by as much as 75-100°C immediately prior to eruption. Ongoing work includes EPMA analysis of plagioclase feldspars and amphiboles to further constrain An-stability and hornblende-cummingtonite relations , respectively, and analysis of titanomagnetite-ilmenite pairs. Continuous decompression experiments are underway with rates ranging from 0.3 MPa/hr to 7.5 MPa/hr, corresponding to total decompression times of 16 hours to 18 days.

Evolution of Inclusions During the 1473 K (1200 °C) Heating Process of EH36 Shipbuilding Steel

NASA Astrophysics Data System (ADS)

Wang, Qiyu; Zou, Xiaodong; Matsuura, Hiroyuki; Wang, Cong

2018-02-01

Evolution behaviors of inclusions of EH36 shipbuilding steel during 1473 K (1200 °C) heating have been studied in conjunction with ex situ scanning electron microscope (SEM) examination and in situ confocal scanning laser microscopy (CSLM) observations. It has been found that Al-Ca-O-S complex inclusions dominate the particles in the cast billet. However, TiN inclusions are profusely populated after heating. Moreover, possible strategies governing austenite growth are offered here.

Mineralogy and Ar-Ar Age of the Tarahumara IIE Iron, with Reference to the Origin of Alkali-Rich Materials

NASA Technical Reports Server (NTRS)

Takeda, Hiroshi; Bogard, Donald D.; Otsuki, Mayumi; Ishii, Teruaki

2003-01-01

Silicate inclusions in nine known IIE irons show diversity in mineralogy, and Colomera, Kodaikanal, Elga and Miles contain alkali-rich silicate inclusions. Bogard et al. showed evidence of a complex parent body evolution for IIE irons based on Ar-39-Ar-40 ages. Colomera contained a sanidine-rich surface inclusion and the K-enrichment trends in the Na-rich inclusions are different from those of other IIEs. To elucidate the origin of K-rich materials, we studied the mineralogy and Ar-Ar age of silicate inclusions from the Tarahumara IIE iron meteorite.

Multiscale model for microstructure evolution in multiphase materials: Application to the growth of isolated inclusions in presence of elasticity.

PubMed

Perez, Danny; Lewis, Laurent J

2006-09-01

We present a multiscale model based on the classical lattice time-dependent density-functional theory to study microstructure evolution in multiphase systems. As a first test of the method, we study the static and dynamic properties of isolated inclusions. Three cases are explored: elastically homogeneous systems, elastically inhomogeneous systems with soft inclusions, and elastically inhomogeneous systems with hard inclusions. The equilibrium properties of inclusions are shown to be consistent with previous results: both homogeneous and hard inclusions adopt a circular shape independent of their size, whereas soft inclusions are circular below a critical radius and elliptic above. In all cases, the Gibbs-Thomson relation is obeyed, except for a change in the prefactor at the critical radius in soft inclusions. Under growth conditions, homogeneous inclusions exhibit a Mullins-Sekerka shape instability [W. Mullins and R. Sekerka, J. Appl. Phys. 34, 323 (1963)], whereas in inhomogeneous systems, the growth of perturbations follows the Leo-Sekerka model [P. Leo and R. Sekerka, Acta Metall. 37, 3139 (1989)]. For soft inclusions, the mode instability regime is gradually replaced by a tip-growing mechanism, which leads to stable, strongly out-of-equilibrium shapes even at very low supersaturation. This mechanism is shown to significantly affect the growth dynamics of soft inclusions, whereas dynamical corrections to the growth rates are negligible in homogeneous and hard inclusions. Finally, due to its microscopic formulation, the model is shown to automatically take into account phenomena caused by the presence of the underlying discrete lattice: anisotropy of the interfacial energy, anisotropy of the kinetics, and preferential excitation of shape perturbations commensurate with the rotational symmetry of the lattice.

Determination of binding constants of cyclodextrin inclusion complexes with amino acids and dipeptides by potentiometric titration.

PubMed

Kahle, Claudia; Holzgrabe, Ulrike

2004-10-01

Cyclodextrins are well known for their ability to separate enantiomers of drugs, natural products, and other chiral substances using HPLC, GC, or CE. The resolution of the enantiomers is due to the formation of diastereomeric complexes between the cyclodextrin and the pairs of enantiomers. The aim of this study was to determine the binding constants of the complexes between alpha- and beta-cyclodextrin and the enantiomers of a series of aliphatic and aromatic amino acids, and dipeptides, using a potentiometric titration method. The results of this method are compared to other methods, and correlated to findings in cyclodextrin-modified capillary electrophoresis and possible complex structures. Potentiometric titration was found to be an appropriate tool to determine the binding constants of cyclodextrin inclusion complexes.

Results of thermal modeling of Smart Energy Coating with phase-transition material for independent electricity generation

NASA Astrophysics Data System (ADS)

Pospelova, I. Y.; Pospelova, M. Y.; Bondarenko, A. S.; Kornilov, D. A.

2018-05-01

The modeling for Smart Energy Coating is presented. The coating is able to produce electricity on the surface of pipelines and structural elements. Along with electric output, Smart Energy Coating ensures the stable temperature conditions of work for structures, pipelines and regulating elements. The energy production scheme is based on the Peltier principle and the insulating layer with a phase transition. Thermally conductive inclusions of the inside layer with a phase transition material ensure the stable operation of the Peltier element.

Exploring academics' views on designs, methods, characteristics and outcomes of inclusive health research with people with intellectual disabilities: a modified Delphi study

PubMed Central

Frankena, T K; Naaldenberg, J; Cardol, M; Meijering, J V; Leusink, G; van Schrojenstein Lantman-de Valk, H M J

2016-01-01

Background The British Medical Journal's (BMJ's) patient revolution strives for collaboration with patients in healthcare and health research. This paper studies collaboration with people with intellectual disabilities (ID) in health research, also known as inclusive health research. Currently, transparency and agreement among academics is lacking regarding its main aspects, preventing upscaling of the patient revolution. Objective This study aims to gain agreement among academics on 3 aspects of inclusive health research for people with ID: (1) designs and methods, (2) most important characteristics and (3) outcomes. Design A Delphi study was conducted with academics with experience in inclusive (health) research and on people with ID. The study consisted of 2 sequential questionnaire rounds (n=24; n=17), followed by in-depth interviews (n=10). Results Academics agreed on (1) a collaborative approach to be most suitable to inclusive health research, (2) characteristics regarding the accessibility and facilitation of inclusive health research, and (3) several outcomes of inclusive health research for people with ID and healthcare. Other characteristics agreed on included: atmosphere, relationship, engagement, partnership and power. It was stressed that these characteristics ensure meaningful inclusion. Interviewed academics voiced the need for a tool supporting the facilitation and evaluation of inclusive health research. There was ambiguity as to what this tool should comprise and the extent to which it was possible to capture the complex process of inclusive health research. Discussion and conclusions This study underlines the need for transparency, facilitation and evaluation of inclusive health research. The need for in-depth interviews after 2 Delphi rounds underlines its complexity and context dependence. To increase process transparency, future research should focus on gaining insight into inclusive health research in its context. A tool could be developed to facilitate and evaluate inclusive health research. This tool will be partially applicable to participatory research in general and thereby upscale the patient revolution. PMID:27540101

Characterization of complexes of nucleoside-5'-phosphorothioate analogues with zinc ions.

PubMed

Sayer, Alon Haim; Itzhakov, Yehudit; Stern, Noa; Nadel, Yael; Fischer, Bilha

2013-10-07

On the basis of the high affinity of Zn(2+) to sulfur and imidazole, we targeted nucleotides such as GDP-β-S, ADP-β-S, and AP3(β-S)A, as potential biocompatible Zn(2+)-chelators. The thiophosphate moiety enhanced the stability of the Zn(2+)-nucleotide complex by about 0.7 log units. ATP-α,β-CH2-γ-S formed the most stable Zn(2+)-complex studied here, log K 6.50, being ~0.8 and ~1.1 log units more stable than ATP-γ-S-Zn(2+) and ATP-Zn(2+) complexes, and was the major species, 84%, under physiological pH. Guanine nucleotides Zn(2+) complexes were more stable by 0.3-0.4 log units than the corresponding adenine nucleotide complexes. Likewise, AP3(β-S)A-zinc complex was ~0.5 log units more stable than AP3A complex. (1)H- and (31)P NMR monitored Zn(2+) titration showed that Zn(2+) coordinates with the purine nucleotide N7-nitrogen atom, the terminal phosphate, and the adjacent phosphate. In conclusion, replacement of a terminal phosphate by a thiophosphate group resulted in decrease of the acidity of the phosphate moiety by approximately one log unit, and increase of stability of Zn(2+)-complexes of the latter analogues by up to 0.7 log units. A terminal phosphorothioate contributed more to the stability of nucleotide-Zn(2+) complexes than a bridging phosphorothioate.

Physico-chemical characterization and antibacterial activity of inclusion complexes of Hyptis martiusii Benth essential oil in β-cyclodextrin.

PubMed

Andrade, Tatianny A; Freitas, Thiago S; Araújo, Francielly O; Menezes, Paula P; Dória, Grace Anne A; Rabelo, Alessandra S; Quintans-Júnior, Lucindo J; Santos, Márcio R V; Bezerra, Daniel P; Serafini, Mairim R; Menezes, Irwin Rose A; Nunes, Paula Santos; Araújo, Adriano A S; Costa, Maria S; Campina, Fábia F; Santos, Antonia T L; Silva, Ana R P; Coutinho, Henrique D M

2017-05-01

Cyclodextrins (CDs) have been used as important pharmaceutical excipients for improve the physicochemical properties of the drugs of low solubility as the essential oil of Hyptis martiusii. This oil is important therapeutically, but the low solubility and bioavailability compromises your use. Therein, the aim of this study was to obtain and to characterize physico-chemically the samples obtained by physical mixture (PM), paste complexation (PC) and slurry complexation (SC) of the essential oil Hyptis martiusii (EOHM) in β-CD, and to compare the antibacterial and modulatory-antibiotic activity of products obtained and oil free. The physicochemical characterization was performed by differential scanning calorimetry (DSC), thermogravimetry/derivative thermogravimetry (TG/DTG), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Karl Fischer titration. Additionally, the antibacterial tests were performed by microdilution technique. Thus, it was observed that the PM method showed low complexing capacity, unlike PC and SC in which it was observed the formation of inclusion complexes. In addition, the second stage of the TG/DTG curves showed that SC was the best method inclusion with mass loss of 6.9% over the PC that was 6.0%. The XRD results corroborate with the results above suggesting the formation of new solid phase and the SEM photomicrographs showed the porous surface of the samples PC and SC. The essential oil alone demonstrated an antibacterial and modulatory effect against the S. aureus and the Gram negative strain, respectively. However, the β-CD and the inclusion complex did not demonstrate any biological activity in the performed antibacterial assays. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Insights into the multi-equilibrium, superstructure system based on β-cyclodextrin and a highly water soluble guest.

PubMed

De Paula, Elgte Elmin B; De Sousa, Frederico B; Da Silva, Júlio César C; Fernandes, Flaviana R; Melo, Maria Norma; Frézard, Frédéric; Grazul, Richard M; Sinisterra, Rubén D; Machado, Flávia C

2012-12-15

Pentamidine isethionate (PNT) is an antiprotozoal active in many cases of leishmaniasis, despite the present limitations including high toxicity and parenteral administration. In the present work, a PNT encapsulation strategy into β-cyclodextrin cavity at 1:1 and 2:1 (βCD:PNT) molar ratios was used in order to improve the drug's physical and chemical properties. Combining thermodynamic and structural approaches such as isothermal titration calorimetry (ITC), electrospray ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance ((1)H NMR, and ROESY) the inclusion process and the thermodynamics parameters were identified. ITC and ESI-MS experimental data suggest the simultaneous formation of different supramolecular complexes in solution. Moreover, NMR data are in accordance with these results, suggesting a deep inclusion of PNT into the βCD cavity, through correlations observed in 2D ROESY contour maps. The systems were also characterized by FTIR, TG/DTA and SEM. These techniques indicate the formation of inclusion complex in the solid state. In vivo PNT activity was evaluated orally in mice. The inclusion complex showed a significant reduction of parasite load compared to free PNT. Copyright © 2012 Elsevier B.V. All rights reserved.

Marburg virus inclusions: A virus-induced microcompartment and interface to multivesicular bodies and the late endosomal compartment.

PubMed

Dolnik, Olga; Stevermann, Lea; Kolesnikova, Larissa; Becker, Stephan

2015-01-01

Filovirus infection of target cells leads to the formation of virally induced cytoplasmic inclusions that contain viral nucleocapsids at different stages of maturation. While the role of the inclusions has been unclear since the identification of Marburg and Ebola viruses, it recently became clear that the inclusions are the sites of viral replication, nucleocapsid formation and maturation. Live cell imaging analyses revealed that mature nucleocapsids are transported from inclusions to the filopodia, which represent the major budding sites. Moreover, inclusions recruit cellular proteins that have been shown to support the transport of nucleocapsids. For example, the tumor susceptibility gene 101 protein (Tsg101) interacts with a late domain motif in the nucleocapsid protein NP and recruits the actin-nucleation factor IQGAP1. Complexes of nucleocapsids together with Tsg101 and IQGAP1 are then co-transported along actin filaments. We detected additional proteins (Alix, Nedd4 and the AAA-type ATPase VPS4) of the endosomal sorting complex required for transport (ESCRT) that are recruited into inclusions. Together, the results suggest that nucleocapsids recruit the machinery that enhances viral budding at the plasma membrane. Furthermore, we identified Lamp1 as a marker of the late endosomal compartment in inclusions, while ER, Golgi, TGN and early endosomal markers were absent. In addition, we observed that LC3, a marker of autophagosomal membranes, was present in inclusions. The 3D structures of inclusions show an intricate structure that seems to accommodate an intimate cooperation between cellular and viral components with the intention to support viral transport and budding. Copyright © 2015 Elsevier GmbH. All rights reserved.

Functionalized poly(ethylene glycol) diacrylate microgels by microfluidics: In situ peptide encapsulation for in serum selective protein detection.

PubMed

Celetti, Giorgia; Natale, Concetta Di; Causa, Filippo; Battista, Edmondo; Netti, Paolo A

2016-09-01

Polymeric microparticles represent a robustly platform for the detection of clinically relevant analytes in biological samples; they can be functionalized encapsulating a multiple types of biologics entities, enhancing their applications as a new class of colloid materials. Microfluidic offers a versatile platform for the synthesis of monodisperse and engineered microparticles. In this work, we report microfluidic synthesis of novel polymeric microparticles endowed with specific peptide due to its superior specificity for target binding in complex media. A peptide sequence was efficiently encapsulated into the polymeric network and protein binding occurred with high affinity (KD 0.1-0.4μM). Fluidic dynamics simulation was performed to optimize the production conditions for monodisperse and stable functionalized microgels. The results demonstrate the easy and fast realization, in a single step, of functionalized monodisperse microgels using droplet-microfluidic technique, and how the inclusion of the peptide within polymeric network improve both the affinity and the specificity of protein capture. Copyright © 2016 Elsevier B.V. All rights reserved.

Titles in highly ranked multidisciplinary psychology journals 1966-2011: more words and punctuation marks allow for the communication of more information.

PubMed

Whissell, Cynthia

2013-12-01

Titles of articles in seven highly ranked multidisciplinary psychology journals for every fifth year between 1966 and 2011 (inclusive) were studied in terms of title length, word length, punctuation density, and word pleasantness, activation, and concreteness (assessed by the Dictionary of Affect in Language). Titles grew longer (by three words) and were more frequently punctuated (by one colon or comma for every other article) between 1966 and 2011. This may reflect the increasing complexity of psychology and satisfy readers' requirements for more specific information. There were significant differences among journals (e.g., titles in the Annual Review of Psychology were scored by the Dictionary of Affect as the most pleasant, and those in Psychological Bulletin as the least pleasant) and among categories of journals (e.g., titles in review journals employed longer words than those in research or association journals). Differences were stable across time and were employed to successfully categorize titles from a validation sample.

Anharmonic and Quantum Fluctuations in Molecular Crystals from Ab Initio Simulations

NASA Astrophysics Data System (ADS)

Rossi, Mariana; Gasparotto, Piero; Ceriotti, Michele

Molecular crystals often exist in multiple competing polymorphs which are challenging to be predicted computationally, but show significantly different physicochemical properties. This challenge is not due only to the combinatorial search space, but also to the complex interplay of subtle effects determine the relative stability of different structures. Here we estimate all contributions to the free energies of these systems with density-functional theory, including the oft-neglected anharmonic contributions and nuclear quantum effects, by using a series of different flavors of thermodynamic integration. As an example, for the two most stable forms of paracetamol we find that anharmonic contributions, different descriptions of van der Waals interactions, and nuclear quantum effects all matter to quantitatively determine the stability of different phases. Our studies indicate that anharmonic free energies could play an important role for molecular crystals composed by large molecules and opens the way for a systematic inclusion of these effects in order to obtain a predictive screening of structures.

;Host-guest; interactions in Captisol®/Coumestrol inclusion complex: UV-vis, FTIR-ATR and Raman studies

NASA Astrophysics Data System (ADS)

Venuti, Valentina; Stancanelli, Rosanna; Acri, Giuseppe; Crupi, Vincenza; Paladini, Giuseppe; Testagrossa, Barbara; Tommasini, Silvana; Ventura, Cinzia Anna; Majolino, Domenico

2017-10-01

The ability of Captisol® (sulphobutylether-β-cyclodextrin, SBE-β-CD), to form inclusion complexes, both in solution and in the solid state, has been tested in order to improve some unfavorable chemical-physical characteristics, such as poor solubility in water, of a bioflavonoid, Coumestrol (Coum), well known for its anti-oxidant, anti-inflammatory, anti-fungal and anti-viral activity. In pure water, a phase-solubility study was carried out to evaluate the enhancement of the solubility of Coum and, therefore, the occurred complexation with the macrocycle. The stoichiometry and the stability constant of the SBE-β-CD/Coum complex were calculated with the phase solubility method and through the Job's plot. After that, the solid SBE-β-CD/Coum complex was prepared utilizing a kneading method. The spectral changes induced by complexation on characteristic vibrational band of Coum were complementary investigated by Fourier transform infrared spectroscopy in attenuated total reflectance geometry (FTIR-ATR) and Raman spectroscopy, putting into evidence the guest chemical groups involved in the "host-guest" interactions responsible of the formation and stabilization of the complex. Particular attention was paid to the Cdbnd O and Osbnd H stretching vibrations, whose temperature-evolution respectively furnished the enthalpy changes associated to the binding of host and guest in solid phase and to the reorganization of the hydrogen bond scheme upon complexation. From the whole set of results, an inclusion geometry is also proposed.

A novel multi-tiered experimental approach unfolding the mechanisms behind cyclodextrin-vitamin inclusion complexes for enhanced vitamin solubility and stability.

PubMed

Braithwaite, Miles C; Kumar, Pradeep; Choonara, Yahya E; du Toit, Lisa C; Tomar, Lomas K; Tyagi, Charu; Pillay, Viness

2017-10-30

This study was conducted to provide a mechanistic account for understanding the synthesis, characterization and solubility phenomena of vitamin complexes with cyclodextrins (CD) for enhanced solubility and stability employing experimental and in silico molecular modeling strategies. New geometric, molecular and energetic analyses were pursued to explicate experimentally derived cholecalciferol complexes. Various CD molecules (α-, β-, γ-, and hydroxypropyl β-) were complexed with three vitamins: cholecalciferol, ascorbic acid and α-tocopherol. The Inclusion Efficiency (IE%) was computed for each CD-vitamin complex. The highest IE% achieved for a cholecalciferol complex was for 'βCDD 3 -8', after utilizing a unique CD:cholecalciferol molar synthesis ratio of 2.5:1, never before reported as successful. 2HPβCD-cholecalciferol, γCD-cholecalciferol and α-tocopherol inclusion complexes (IC's) reached maximal IE% with a CD:vitamin molar ratio of 5:1. The results demonstrate that IE%, thermal stability, concentration, carrier solubility, molecular mechanics and intended release profile are key factors to consider when synthesizing vitamin-CD complexes. Phase-solubility data provided insights into the design of formulations with IC's that may provide analogous oral vitamin release profiles even when hydrophobic and hydrophilic vitamins are co-incorporated. Static lattice atomistic simulations were able to validate experimentally derived cholecalciferol IE phenomena and are invaluable parameters when approaching formulation strategies using CD's for improved solubility and efficacy of vitamins. Copyright © 2017 Elsevier B.V. All rights reserved.

Stable isotope compositions of speleothems from the last interglacial - Spatial patterns of climate fluctuations in Europe

NASA Astrophysics Data System (ADS)

Demény, Attila; Kern, Zoltán; Czuppon, György; Németh, Alexandra; Leél-Őssy, Szabolcs; Siklósy, Zoltán; Lin, Ke; Hu, Hsun-Ming; Shen, Chuan-Chou; Vennemann, Torsten W.; Haszpra, László

2017-04-01

Studies on the last interglacial (LIG) can provide information on how our environment behaved in a period of slightly higher global temperatures at about 125 ± 4 ka, even if it is not the best analogue for the Holocene. The available LIG climate proxy records are usually better preserved and can be studied at a higher resolution than those of the preceding interglacials, allowing detailed comparisons. This paper presents complex stable hydrogen, carbon and oxygen isotope records obtained for carbonate (δ13C and δ18Ocarb) and fluid inclusion hosted water (δD and δ18Ow) of a stalagmite from the Baradla Cave system in Central Europe that covers most of the LIG, as proven by U-Th dates. Comparing its C and O isotope data with records reported for other speleothem (cave-hosted carbonate) deposits from Europe revealed the complex behavior of these climate proxies, with a concerted relative increase in 18O of carbonates from 128 to 120 ka and synchronized shifts in the opposite direction after 119 ka. The hydrogen isotope analyses of inclusion-hosted water extracted from the BAR-II stalagmite also correspond to the regional climate proxy records, with meaningful deviations from global temperature trends. Beside following the general paleotemperature pattern from the climate optimum (high δD values up to -64‰ around 120 ka) to the subsequent cooling starting at about 119 ka (low δD values down to -90‰ at about 109 ka), a period between 126.5 and 123 ka with low δD values (down to -81‰) is detected in the BAR-II stalagmite. Although the isotope shifts are muted in the C-O isotope data of carbonate due to competitive fractionation processes, the δ13C data show a positive relationship with the δD pattern, indicating humidity - and possibly temperature - variations. The periods with low δD values fit well to temperature and humidity changes inferred from proxy records from western Europe to the eastern Mediterranean. Spatial distributions of these variables show, that at about 125 ± 2 ka the Mediterranean region was characterized by warm, humid conditions and enhanced seasonality with elevated winter precipitation. The combined interpretation of stable isotope data revealed that the Alpine and Mediterranean regions behaved differently during Greenland Stadial 26 (GS26, ∼119 to 116.2 ka). While the Alpine records fluctuated in close agreement with the Central Greenland ice core δ18O data, the BAR-II stalagmite show a positive δ18Ocarb anomaly. The Baradla data indicate enhanced aridity and seasonality for a part of GS26, with the relative dominance of summer precipitation and Mediterranean moisture contribution. Following the GS26 event, the effect of long-term global cooling becomes dominant in the Baradla isotope records and leads to glacial inception at about 109 ka.

Supra-molecular inclusion complexation of ionic liquid 1-butyl-3-methylimidazolium octylsulphate with α- and β-cyclodextrins

NASA Astrophysics Data System (ADS)

Banjare, Manoj Kumar; Behera, Kamalakanta; Satnami, Manmohan L.; Pandey, Siddharth; Ghosh, Kallol K.

2017-12-01

Host-guest complexation between ionic liquid (IL) 1-butyl-3-methylimidazolium octylsulphate [Bmim][OS] and cyclodextrins (α- and β- CDs) have been studied. Surface tension, conductivity measurements revealed the formation of 1:1 (M) stoichiometry for inclusion complexes (ICs) and further confirmed by UV-Visible and FT-IR results. The nature of the complexes has been established using interfacial and thermodynamic parameters. The aggregation number, Stern-Volmer constants, association constants were obtained from fluorescence quenching and Benesi-Hildebrand methods. The critical micelle concentration (cmc) and association constants of [Bmim][OS] are higher for β-CD as compared to α-CD. FT-IR spectra indicated that CDs and [Bmim][OS] could from ICs with stoichiometry 1:1 (M).

Occurrence and mineral chemistry of high pressure phases, Portrillo basalt, southcentral New Mexico. M.S. Thesis. Final Technical Report, 1 Jun. 1978 - 31 May 1980

NASA Technical Reports Server (NTRS)

Hoffer, J. M.; Ortiz, T. S.

1980-01-01

Inclusions of clinopyroxenite, kaersutiteclinopyroxenite, kaersutite-rich inclusions, wehrlite and olivine-clinopyroxenite together with megacrysts of feldspar, kaersutite and spinel are found loose on the flanks of cinder cones, as inclusions within lava flows and within the cores of volcanic bombs in the Quaternary alkali-olivine basalt of the West Potrillo Mountains, southcentral New Mexico. Based on petrological and geochemical evidence the megacysts are interpreted to be phenocrysts which formed at great depth rather that xenocrysts of larger crystal aggregates. These large crystals are believed to have formed as stable phases at high temperature and pressure and have partially reacted with the basalt to produce subhedral to anhedral crystal boundaries. It can be demonstrated that the mafic and ultramafic crystal aggregates were derived from an alkali-basalt source rock generated in the mantle. The inclusions are believed to represent a cumulus body or bodies injected within the lower crust or upper mantle.

Highly efficient recovery of functional single-chain Fv fragments from inclusion bodies overexpressed in Escherichia coli by controlled introduction of oxidizing reagent--application to a human single-chain Fv fragment.

PubMed

Tsumoto, K; Shinoki, K; Kondo, H; Uchikawa, M; Juji, T; Kumagai, I

1998-10-01

An improved and efficient refolding system for a single-chain antibody fragment (scFv) from inclusion bodies expressed in Escherichia coli was developed. Stepwise removal of denaturing reagent and controlled addition of oxidizing reagent were found to be the most effective conditions to achieve for almost complete recovery of functional monomeric scFv from inclusion bodies. Adding L-arginine to the refolding solution also increased the yield of refolded functional scFv. The single-chain Fv fragments of both a mouse anti-lysozyme monoclonal antibody, HyHEL10, and a human monoclonal antibody against the D antigen of the Rh blood group, D10, in solubilized inclusion bodies could be refolded under these conditions with yields of up to 95%. The refolding procedures developed in this study will contribute to providing a stable supply of large amounts of human single-chain Fv fragments.

Formation and characterization of chitosan-protein particles with fractal whey protein aggregates.

PubMed

Ahmed, Khouloud Fekih; Aschi, Adel; Nicolai, Taco

2018-05-15

Hybrid protein-polysaccharide particles were formed by complexation of fractal whey protein aggregates and the cationic polysaccharide chitosan. The fractal aggregates were preformed by heating native whey protein isolate at pH 7 and subsequently mixed with chitosan at pH 3 where these proteins and polysaccharides don't interact with each other. Stable dispersions of protein-polysaccharide particles were formed spontaneously when the pH was gradually increased between 4.1 and 6.8, whereas in the absence of chitosan the fractal aggregates precipitated between pH 4.1 and 5.4. Potentiometric titration of the mixtures showed that deprotonation of both components was affected by complexation. With increasing pH, the size of the complexes increased sharply between pH 4.1. and pH 4.5, remained constant up to pH 5.6 and then increased again. A minimum amount of chitosan was needed to form stable complexes at pH 5.0 and the size of the complexes decreased with increasing chitosan concentration. Light scattering showed that the complexes were stable to dilution and had a self similar structure with a fractal dimensions close to two. The effect of changing the pH on the size and stability of the complexes was investigated. Suspensions of complexes of preformed whey protein aggregates and chitosan are more stable up to high pH (6.8) than complexes between native WPI and chitosan as reported in the literature. Copyright © 2018. Published by Elsevier B.V.

Study protocol: developing a decision system for inclusive housing: applying a systematic, mixed-method quasi-experimental design.

PubMed

Zeeman, Heidi; Kendall, Elizabeth; Whitty, Jennifer A; Wright, Courtney J; Townsend, Clare; Smith, Dianne; Lakhani, Ali; Kennerley, Samantha

2016-03-15

Identifying the housing preferences of people with complex disabilities is a much needed, but under-developed area of practice and scholarship. Despite the recognition that housing is a social determinant of health and quality of life, there is an absence of empirical methodologies that can practically and systematically involve consumers in this complex service delivery and housing design market. A rigorous process for making effective and consistent development decisions is needed to ensure resources are used effectively and the needs of consumers with complex disability are properly met. This 3-year project aims to identify how the public and private housing market in Australia can better respond to the needs of people with complex disabilities whilst simultaneously achieving key corporate objectives. First, using the Customer Relationship Management framework, qualitative (Nominal Group Technique) and quantitative (Discrete Choice Experiment) methods will be used to quantify the housing preferences of consumers and their carers. A systematic mixed-method, quasi-experimental design will then be used to quantify the development priorities of other key stakeholders (e.g., architects, developers, Government housing services etc.) in relation to inclusive housing for people with complex disabilities. Stakeholders randomly assigned to Group 1 (experimental group) will participate in a series of focus groups employing Analytical Hierarchical Process (AHP) methodology. Stakeholders randomly assigned to Group 2 (control group) will participate in focus groups employing existing decision making processes to inclusive housing development (e.g., Risk, Opportunity, Cost, Benefit considerations). Using comparative stakeholder analysis, this research design will enable the AHP methodology (a proposed tool to guide inclusive housing development decisions) to be tested. It is anticipated that the findings of this study will enable stakeholders to incorporate consumer housing preferences into commercial decisions. Housing designers and developers will benefit from the creation of a parsimonious set of consumer-led housing preferences by which to make informed investments in future housing and contribute to future housing policy. The research design has not been applied in the Australian research context or elsewhere, and will provide a much needed blueprint for market investment to develop viable, consumer directed inclusive housing options for people with complex disability.

Native and β-cyclodextrin-enclosed curcumin: entrapment within liposomes and their in vitro cytotoxicity in lung and colon cancer.

PubMed

Rahman, Shafiur; Cao, Siyu; Steadman, Kathryn J; Wei, Ming; Parekh, Harendra S

2012-01-01

With a view to improving the solubility and delivery characteristics of poorly water-soluble drugs, we prepared β-cyclodextrin-curcumin (βCD-C) inclusion complexes (hydrophilic curcumin) and entrapped both native curcumin (hydrophobic) and the complexes separately into liposomes; these were then assessed for in vitro cytotoxicity in lung and colon cancer cell lines. Optimization of curcumin entrapment within βCD was achieved, with the resultant βCD-C complexes prepared by methanol reflux. Inclusion complexes were confirmed using UV spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction. The water solubility of βCD-C complexes improved markedly (c.f. native curcumin) and successful entrapment of complexes into liposomes, prepared using a thin-film hydration approach, was also achieved. All the liposomal formulations were characterized for curcumin and βCD-C complex entrapment efficiency, particle size, polydispersity and stability at 2-8°C. Curcumin, βCD-C complex and their optimized liposomal formulations were evaluated for anticancer activity in lung (A-459) and colon (SW-620) cancer cell lines. All curcumin-containing formulations tested were effective in inhibiting cell proliferation, as determined via an MTT assay. The median effective dose (EC(50)) for all curcumin formulations was found to be in the low µM range for both lung and colon cancer cell lines tested. Our results confirm that βCD inclusion complexes of poorly water soluble drugs, such as curcumin can be entrapped within biocompatible vesicles such as liposomes, and this does not preclude their anticancer activity.

Structure and organization of nanosized-inclusion-containing bilayer membranes

NASA Astrophysics Data System (ADS)

Ren, Chun-Lai; Ma, Yu-Qiang

2009-07-01

Based on a considerable amount of experimental evidence for lateral organization of lipid membranes which share astonishingly similar features in the presence of different inclusions, we use a hybrid self-consistent field theory (SCFT)/density-functional theory (DFT) approach to deal with bilayer membranes embedded by nanosized inclusions and explain experimental findings. Here, the hydrophobic inclusions are simple models of hydrophobic drugs or other nanoparticles for biomedical applications. It is found that lipid/inclusion-rich domains are formed at moderate inclusion concentrations and disappear with the increase in the concentration of inclusions. At high inclusion content, chaining of inclusions occurs due to the effective depletion attraction between inclusions mediated by lipids. Meanwhile, the increase in the concentration of inclusions can also cause thickening of the membrane and the distribution of inclusions undergoes a layering transition from one-layer structure located in the bilayer midplane to two-layer structure arranged into the two leaflets of a bilayer. Our theoretical predictions address the complex interactions between membranes and inclusions suggesting a unifying mechanism which reflects the competition between the conformational entropy of lipids favoring the formation of lipid- and inclusion-rich domains in lipids and the steric repulsion of inclusions leading to the uniform dispersion.

Mineralogical, textural, geochemical and thermometric characteristics of Central Anatolian fluorites (Turkey): Tracing the origin of post-magmatic fluids

NASA Astrophysics Data System (ADS)

Cosanay, Pelin; Mutlu, Halim; Koc, Sükrü; Cevik, Nihal; Oztürk, Ceyda; Varol, Ece

2016-04-01

In this study, we investigate the spatial distribution of fluorite veins in Central Anatolia with emphasis on mineralogical, textural, geochemical and thermometric variations. The studied fluorite mineralizations (Kaman, Akçakent, Pöhrenk and Şefaatli mineralizations from west to east) are located on northern part of Kırşehir Massif which is a part of Central Anatolian Crystalline Complex that is bordered by the İzmir-Ankara-Erzincan Suture Zone. The Kaman, Akçakent and Şefaatli fluorite deposits are formed in association with magmatic rocks such as syenite and monzonite / monzodiorite in composition which are of Upper Cretaceous age. Fluorite in these deposits occurs as purple- and green-colored stockwork veins and/or disseminations along fault/fracture systems and is accompanied by quartz and rare pyrite. The Pöhrenk ore, however, is precipitated as space filling-breccia type within karstic voids of Eocene limestones and marl levels. The silicification/carbonatization and barite occurrences are found as the main alteration and secondary products of mineralization. Thickness of fluorite veins is between 2 and 30 cm. ΣREE contents of host rocks and fluorite veins are in the range of 2-806 ppm and 20-390 ppm, respectively. In element variation diagrams constructed for both host rocks and fluorite mineralizations, LREE concentrations are found to be greater than HREEs. REE contents of green-colored fluorites are about 10-fold higher than those of purple-colored ones. Negative Ce and Eu anomalies indicate high oxygen fugacity for the mineralizing fluids. Fluid inclusion studies indicated three different types of inclusions: 1) two-phase (liquid-vapor) primary and secondary inclusions, 2) single-phase (liquid) primary and secondary inclusions and 3) two-phase (liquid-vapor) and single-phase (liquid) pseudo-secondary inclusions. Results of homogenization temperatures from a number of about 200 measurements chiefly on fluorite and less often quartz and barite crystals point to a temperature range of 90-210°C and a salinity range of 0.2 to 23.0 NaCl equivalent wt%. Our ongoing survey which has been further focused on the time of mineralization and Sr-Nd isotope compositions of fluorites and host rocks as well as stable isotope systematics of accessory minerals will lead to a better understanding of the origin of mineralizing fluids that precipitated Central Anatolian fluorites.

Elaboration of antibiofilm surfaces functionalized with antifungal-cyclodextrin inclusion complexes.

PubMed

Gharbi, Aïcha; Humblot, Vincent; Turpin, Frédéric; Pradier, Claire-Marie; Imbert, Christine; Berjeaud, Jean-Marc

2012-07-01

To tackle the loss of activity of surfaces functionalized by coating and covalently bound molecules to materials, an intermediate system implying the noncovalent immobilization of active molecules in the inner cavity of grafted cyclodextrins (CDs) was investigated. The antifungal and antibiofilm activities of the most stable complexes of Anidulafungin (ANF; echinocandin) and thymol (THY; terpen) in various CDs were demonstrated to be almost the same as the free molecules. The selected CD was covalently bond to self-assembled monolayers on gold surfaces. The immobilized antifungal agents reduced the number of culturable Candida albicans ATCC 3153 attached to the surface by 64 ± 8% for ANF and 75 ± 15% for THY. The inhibitory activity was persistent for THY-loaded samples, whereas it was completely lost for ANF-loaded surfaces after one use. However, reloading of the echinocandin restored the activity. Using fluorescent dying and confocal microscopy, it was proposed that the ANF-loaded surfaces inhibited the adherence of the yeasts, whereas the activity of immobilized THY was found fungicidal. This kind of tailored approach for functionalizing surfaces that could allow a progressive release of ANF or THY gave promising results but still needs to be improved to display a full activity. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Comparison of generation 3 polyamidoamine dendrimer and generation 4 polypropylenimine dendrimer on drug loading, complex structure, release behavior, and cytotoxicity

PubMed Central

Shao, Naimin; Su, Yunzhang; Hu, Jingjing; Zhang, Jiahai; Zhang, Hongfeng; Cheng, Yiyun

2011-01-01

Background Polyamidoamine (PAMAM) and polypropylenimine (PPI) dendrimers are the commercially available and most widely used dendrimers in pharmaceutical sciences and biomedical engineering. In the present study, the loading and release behaviors of generation 3 PAMAM and generation 4 PPI dendrimers with the same amount of surface amine groups (32 per dendrimer) were compared using phenylbutazone as a model drug. Methods The dendrimer-phenylbutazone complexes were characterized by 1H nuclear magnetic resonance and nuclear Overhauser effect techniques, and the cytotoxicity of each dendrimer was evaluated. Results Aqueous solubility results suggest that the generation 3 PAMAM dendrimer has a much higher loading ability towards phenylbutazone in comparison with the generation 4 PPI dendrimer at high phenylbutazone-dendrimer feeding ratios. Drug release was much slower from the generation 3 PAMAM matrix than from the generation 4 PPI dendrimer. In addition, the generation 3 PAMAM dendrimer is at least 50-fold less toxic than generation 4 PPI dendrimer on MCF-7 and A549 cell lines. Conclusion Although the nuclear Overhauser effect nuclear magnetic resonance results reveal that the generation 4 PPI dendrimer with a more hydrophobic interior encapsulates more phenylbutazone, the PPI dendrimer-phenylbutazone inclusion is not stable in aqueous solution, which poses a great challenge during drug development. PMID:22267921

Hartree-Fock and density functional theory study of alpha-cyclodextrin conformers.

PubMed

Jiménez, Verónica; Alderete, Joel B

2008-01-31

Herein, we report the geometry optimization of four conformers of alpha-cyclodextrin (alpha-CD) by means of PM3, HF/STO-3G, HF/3-21G, HF/6-31G(d), B3LYP/6-31G(d), and X3LYP/6-31G(d) calculations. The analysis of several geometrical parameters indicates that all conformers possess bond lengths, angles, and dihedrals that agree fairly well with the crystalline structure of alpha-CD. However, only three of them (1-3) resemble the polar character of CDs and show intramolecular hydrogen-bonding patterns that agree with experimental NMR data. Among them, conformer 3 appears to be the most stable species both in the gas phase and in solution; therefore, it is expected to be the most suitable representative structure for alpha-CD conformation. The purpose of selecting such a species is to identify an appropriate structure to be employed as a starting point for reliable computational studies on complexation phenomena. Our results indicate that the choice of a particular alpha-CD conformer should affect the results of ab initio computational studies on the inclusion complexation with this cyclodextrin since both the direction and the magnitude of the dipole moment depend strongly on the conformation of alpha-CD.

Educating towards Inclusive Education: Assessing a Teacher-Training Program for Working with Pupils with Special Educational Needs and Disabilities (SEND) Enrolled in General Education Schools

ERIC Educational Resources Information Center

Shani, Michal; Hebel, Orly

2016-01-01

Implementing inclusive education is one of the major challenges facing the educational system. One of the main difficulties in implementing inclusive education is that general education teachers receive insufficient training to work in complex teaching contexts and to respond to the unique needs of all the pupils in their classroom. The objective…

Study of Te Inclusion and Related Point Defects in THM-Growth CdMnTe Crystal

NASA Astrophysics Data System (ADS)

Mao, Yifei; Zhang, Jijun; Min, Jiahua; Liang, Xiaoyan; Huang, Jian; Tang, Ke; Ling, Liwen; Li, Ming; Zhang, Ying; Wang, Linjun

2018-02-01

This study establishes a model for describing the interaction between Te inclusions, dislocations and point defects in CdMnTe crystals. The role of the complex environment surrounding the formation of Te inclusions was analyzed. Images of Te inclusions captured by scanning electron microscope and infrared microscope were used to observe the morphology of Te inclusions. The morphology of Te inclusions is discussed in light of crystallography, from the crystal growth temperature at 900°C to the melting temperature of Te inclusions using the traveling heater method. The dislocation nets around Te inclusions were calculated by counting lattice mismatches between the Te inclusions and the bulk CdMnTe at 470°C. The point defects of Te antisites were found to be gathered around Te inclusions, with dislocation climb during the cooling phase of crystal growth from 470°C to room temperature. The Te inclusions, dislocation nets and surrounding point defects are considered to be an entirety for evaluating the effect of Te inclusions on CdMnTe detector performance, and an effective mobility-lifetime product (μτ) was obtained.

Polymer-free nanofibers from vanillin/cyclodextrin inclusion complexes: high thermal stability, enhanced solubility and antioxidant property.

PubMed

Celebioglu, Asli; Kayaci-Senirmak, Fatma; İpek, Semran; Durgun, Engin; Uyar, Tamer

2016-07-13

Vanillin/cyclodextrin inclusion complex nanofibers (vanillin/CD-IC NFs) were successfully obtained from three modified CD types (HPβCD, HPγCD and MβCD) in three different solvent systems (water, DMF and DMAc) via an electrospinning technique without using a carrier polymeric matrix. Vanillin/CD-IC NFs with uniform and bead-free fiber morphology were successfully produced and their free-standing nanofibrous webs were obtained. The polymer-free CD/vanillin-IC-NFs allow us to accomplish a much higher vanillin loading (∼12%, w/w) when compared to electrospun polymeric nanofibers containing CD/vanillin-IC (∼5%, w/w). Vanillin has a volatile nature yet, after electrospinning, a significant amount of vanillin was preserved due to complex formation depending on the CD types. Maximum preservation of vanillin was observed for vanillin/MβCD-IC NFs which is up to ∼85% w/w, besides, a considerable amount of vanillin (∼75% w/w) was also preserved for vanillin/HPβCD-IC NFs and vanillin/HPγCD-IC NFs. Phase solubility studies suggested a 1 : 1 molar complexation tendency between guest vanillin and host CD molecules. Molecular modelling studies and experimental findings revealed that vanillin : CD complexation was strongest for MβCD when compared to HPβCD and HPγCD in vanillin/CD-IC NFs. For vanillin/CD-IC NFs, water solubility and the antioxidant property of vanillin was improved significantly owing to inclusion complexation. In brief, polymer-free vanillin/CD-IC NFs are capable of incorporating a much higher loading of vanillin and effectively preserve volatile vanillin. Hence, encapsulation of volatile active agents such as flavor, fragrance and essential oils in electrospun polymer-free CD-IC NFs may have potential for food related applications by integrating the particularly large surface area of NFs with the non-toxic nature of CD and inclusion complexation benefits, such as high temperature stability, improved water solubility and an enhanced antioxidant property, etc.

Positive in vitro wound healing effects of functional inclusion bodies of a lipoxygenase from the Mexican axolotl.

PubMed

Stamm, Anne; Strauß, Sarah; Vogt, Peter; Scheper, Thomas; Pepelanova, Iliyana

2018-04-07

AmbLOXe is a lipoxygenase, which is up-regulated during limb-redevelopment in the Mexican axolotl, Ambystoma mexicanum, an animal with remarkable regeneration capacity. Previous studies have shown that mammalian cells transformed with the gene of this epidermal lipoxygenase display faster migration and wound closure rate during in vitro wound healing experiments. In this study, the gene of AmbLOXe was codon-optimized for expression in Escherichia coli and was produced in the insoluble fraction as protein aggregates. These inclusion bodies or nanopills were shown to be reservoirs containing functional protein during in vitro wound healing assays. For this purpose, functional inclusion bodies were used to coat cell culture surfaces prior cell seeding or were added directly to the medium after cells reached confluence. In both scenarios, AmbLOXe inclusion bodies led to faster migration rate and wound closure, in comparison to controls containing either no AmbLOXe or GFP inclusion bodies. Our results demonstrate that AmbLOXe inclusion bodies are functional and may serve as stable reservoirs of this enzyme. Nevertheless, further studies with soluble enzyme are also necessary in order to start elucidating the exact molecular substrates of AmbLOXe and the biochemical pathways involved in the wound healing effect.

NMR study on the stabilization and chiral discrimination of sulforaphane enantiomers and analogues by cyclodextrins.

PubMed

Recio, Rocío; Elhalem, Eleonora; Benito, Juan M; Fernández, Inmaculada; Khiar, Noureddine

2018-05-01

Sulforaphane (SFN), a phytochemical isolated from broccoli, is an important antitumoral compound with additional beneficial effect on other important diseases. However, the chemical instability of SFN has hampered its clinical use. In order to circumvent this problem, we report the first comparative study on the inclusion complexes of SFN and SFN homologues with different cyclodextrins by NMR spectroscopy. From this study it has been shown that α-CD is the most indicated cyclodextrin for the stabilization of SFN and SFN homologues, and that the highest affinity constant is that of the isothiocyanate obtained from the wasabi. Furthermore, the study of the inclusion complexes of α-CD and the non-natural SFN and analogues with S absolute configuration at sulfur shows for the first time that α-CD is able to discriminate between the two enantiomers, with the natural R enantiomers forming the inclusion complexes with higher affinity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of ultrasonic treatment on amylose-lipid complex formation and properties of sweet potato starch-based films.

PubMed

Liu, Pengfei; Wang, Rui; Kang, Xuemin; Cui, Bo; Yu, Bin

2018-06-01

To investigate the effect of ultrasonic treatment on the properties of sweet potato starch and sweet potato starch-based films, the complexing index, thermograms and diffractograms of the sweet potato starch-lauric acid composite were tested, and light transmission, microstructure, and mechanical and moisture barrier properties of the films were measured. The results indicated that the low power density ultrasound was beneficial to the formation of an inclusion complex. In thermograms, the gelatinization enthalpies of the ultrasonically treated starches were lower than those of the untreated sample. With the ultrasonic amplitude increased from 40% to 70%, the melting enthalpy (ΔH) of the inclusion complex gradually decreased. X-ray diffraction revealed that the diffraction intensity of the untreated samples was weaker than that of the ultrasonically treated samples. When the ultrasonic amplitude was above 40%, the diffraction intensity and relative crystallinity of inclusion complex gradually decreased. The scanning electronic microscope showed that the surface of the composite films became smooth after being treated by ultrasonication. Ultrasonication led to a reduction in film surface roughness under atomic force microscopy analysis. The films with ultrasonic treatment exhibited higher light transmission, lower elongation at break, higher tensile strength and better moisture barrier property than those without ultrasonic treatment. Copyright © 2018 Elsevier B.V. All rights reserved.

Quantitative ROESY analysis of computational models: structural studies of citalopram and β-cyclodextrin complexes by (1) H-NMR and computational methods.

PubMed

Ali, Syed Mashhood; Shamim, Shazia

2015-07-01

Complexation of racemic citalopram with β-cyclodextrin (β-CD) in aqueous medium was investigated to determine atom-accurate structure of the inclusion complexes. (1) H-NMR chemical shift change data of β-CD cavity protons in the presence of citalopram confirmed the formation of 1 : 1 inclusion complexes. ROESY spectrum confirmed the presence of aromatic ring in the β-CD cavity but whether one of the two or both rings was not clear. Molecular mechanics and molecular dynamic calculations showed the entry of fluoro-ring from wider side of β-CD cavity as the most favored mode of inclusion. Minimum energy computational models were analyzed for their accuracy in atomic coordinates by comparison of calculated and experimental intermolecular ROESY peak intensities, which were not found in agreement. Several least energy computational models were refined and analyzed till calculated and experimental intensities were compatible. The results demonstrate that computational models of CD complexes need to be analyzed for atom-accuracy and quantitative ROESY analysis is a promising method. Moreover, the study also validates that the quantitative use of ROESY is feasible even with longer mixing times if peak intensity ratios instead of absolute intensities are used. Copyright © 2015 John Wiley & Sons, Ltd.

A high-throughput immobilized bead screen for stable proteins and multi-protein complexes

PubMed Central

Lockard, Meghan A.; Listwan, Pawel; Pedelacq, Jean-Denis; Cabantous, Stéphanie; Nguyen, Hau B.; Terwilliger, Thomas C.; Waldo, Geoffrey S.

2011-01-01

We describe an in vitro colony screen to identify Escherichia coli expressing soluble proteins and stable, assembled multiprotein complexes. Proteins with an N-terminal 6His tag and C-terminal green fluorescent protein (GFP) S11 tag are fluorescently labeled in cells by complementation with a coexpressed GFP 1–10 fragment. After partial colony lysis, the fluorescent soluble proteins or complexes diffuse through a supporting filtration membrane and are captured on Talon® resin metal affinity beads immobilized in agarose. Images of the fluorescent colonies convey total expression and the level of fluorescence bound to the beads indicates how much protein is soluble. Both pieces of information can be used together when selecting clones. After the assay, colonies can be picked and propagated, eliminating the need to make replica plates. We used the method to screen a DNA fragment library of the human protein p85 and preferentially obtained clones expressing the full-length ‘breakpoint cluster region-homology' and NSH2 domains. The assay also distinguished clones expressing stable multi-protein complexes from those that are unstable due to missing subunits. Clones expressing stable, intact heterotrimeric E.coli YheNML complexes were readily identified in libraries dominated by complexes of YheML missing the N subunit. PMID:21642284

Glycosaminoglycan-resistant and pH-sensitive lipid-coated DNA complexes produced by detergent removal method.

PubMed

Lehtinen, Julia; Hyvönen, Zanna; Subrizi, Astrid; Bunjes, Heike; Urtti, Arto

2008-10-21

Cationic polymers are efficient gene delivery vectors in in vitro conditions, but these carriers can fail in vivo due to interactions with extracellular polyanions, i.e. glycosaminoglycans (GAG). The aim of this study was to develop a stable gene delivery vector that is activated at the acidic endosomal pH. Cationic DNA/PEI complexes were coated by 1,2-dioleylphosphatidylethanolamine (DOPE) and cholesteryl hemisuccinate (CHEMS) (3:2 mol/mol) using two coating methods: detergent removal and mixing with liposomes prepared by ethanol injection. Only detergent removal produced lipid-coated DNA complexes that were stable against GAGs, but were membrane active at low pH towards endosome mimicking liposomes. In relation to the low cellular uptake of the coated complexes, their transfection efficacy was relatively high. PEGylation of the coated complexes increased their cellular uptake but reduced the pH-sensitivity. Detergent removal was thus a superior method for the production of stable, but acid activatable, lipid-coated DNA complexes.

What can one sample tell us? Stable isotopes can assess complex processes in national assessments of lakes, rivers and streams.

EPA Science Inventory

Stable isotopes can be very useful in large-scale monitoring programs because samples for isotopic analysis are easy to collect, and isotopes integrate information about complex processes such as evaporation from water isotopes and denitrification from nitrogen isotopes. Traditi...

β-cyclodextrin-ferrocene host-guest complex multifunctional labeling triple amplification strategy for electrochemical immunoassay of subgroup J of avian leukosis viruses.

PubMed

Shang, Kun; Wang, Xindong; Sun, Bing; Cheng, Ziqiang; Ai, Shiyun

2013-07-15

A novel sandwich-type electrochemical immunosensor was fabricated for ultrasensitive detection of subgroup J of avian leukosis virus (ALVs-J) by employing β-cyclodextrin-ferrocene (CD-Fc) host-guest complex multifunctional Fe3O4 nanospheres as labels and β-cyclodextrin functional graphene sheets (CD-GS) nanocomposite as sensor platform. The sensitivity was greatly improved based on the triple amplification strategy. Firstly, the CD-GS improved the electron transfer rate as well as increasing the surface area to capture a large amount of primary antibodies (Ab1). Secondly, the CD on the Fe3O4 surface with strong recognition capability could form stable CD-Fc host-guest inclusion complex and provided larger free room for the conjugation of secondary antibodies (Ab2) and glucose oxidase (GOD). Finally, the conjugated GOD exhibited extraordinary electrochemical biocatalysis towards the reduction reaction of Fc(+) by glucose. Under the optimized conditions, the electrochemical immunosensor exhibited a wide working range from 10(2.27)-10(3.50) TCID50/mL (TCID50: 50% tissue culture infective dose) with a low detection limit of 10(2.19) TCID50/mL (S/N=3). The selectivity, reproducibility, and stability are acceptable. The assay was evaluated for real avian serum sample, receiving satisfactory results. This new type of triple amplification strategy may provide potential applications for the clinic application. Copyright © 2013 Elsevier B.V. All rights reserved.

An Integrated Study on the Evolution of Inclusions in EH36 Shipbuilding Steel with Mg Addition: From Casting to Welding

NASA Astrophysics Data System (ADS)

Zou, Xiaodong; Zhao, Dapeng; Sun, Jincheng; Wang, Cong; Matsuura, Hiroyuki

2018-04-01

Inclusion evolution behaviors, in terms of composition, size, and number density, and associated influence on the microstructures of the as-cast slabs, rolled plates, and simulated welded samples of plain EH36 and EH36-Mg shipbuilding steels have been systematically investigated. The results indicate that the inclusions in the as-cast plain EH36 are almost Al-Ca-S-O-(Mn) complex oxides with sizes ranging from 1.0 to 2.0 μm. After Mg addition, a large amount of individually fine MnS precipitates and Mg-containing Ti-Al-Mg-O-(Mn-S) complex inclusions are generated, which significantly refine the microstructure and are conducive to the nucleation of acicular ferrite in the rolled and welded sample. Moreover, after rolling and welding thermal simulation, the number of individual MnS decreases gradually due to its precipitation on the surface of Ti-Al-Mg-O oxides.

Hydrodynamic interactions in freely suspended liquid crystal films

NASA Astrophysics Data System (ADS)

Kuriabova, Tatiana; Powers, Thomas R.; Qi, Zhiyuan; Goldfain, Aaron; Park, Cheol Soo; Glaser, Matthew A.; Maclennan, Joseph E.; Clark, Noel A.

2016-11-01

Hydrodynamic interactions play an important role in biological processes in cellular membranes, a large separation of length scales often allowing such membranes to be treated as continuous, two-dimensional (2D) fluids. We study experimentally and theoretically the hydrodynamic interaction of pairs of inclusions in two-dimensional, fluid smectic liquid crystal films suspended in air. Such smectic membranes are ideal systems for performing controlled experiments as they are mechanically stable, of highly uniform structure, and have well-defined, variable thickness, enabling experimental investigation of the crossover from 2D to 3D hydrodynamics. Our theoretical model generalizes the Levine-MacKintosh theory of point-force response functions and uses a boundary-element approach to calculate the mobility matrix for inclusions of finite extent. We describe in detail the theoretical and computational approach previously outlined in Z. Qi et al., Phys. Rev. Lett. 113, 128304 (2014), 10.1103/PhysRevLett.113.128304 and extend the method to study the mutual mobilities of inclusions with asymmetric shapes. The model predicts well the observed mutual mobilities of pairs of circular inclusions in films and the self-mobility of a circular inclusion in the vicinity of a linear boundary.

Characterization of mitotane (o,p'-DDD)--cyclodextrin inclusion complexes: phase-solubility method and NMR.

PubMed

Alfonsi, R; Attivi, D; Astier, A; Socha, M; Morice, S; Gibaud, S

2013-05-01

Mitotane (o,p'-dichlorodimethyl dichloroethane [o,p'-DDD]) is used for the treatment of adrenocortical cancer and occasionally Cushing's syndrome. This drug is very poorly soluble in water, and following oral administration, approximately 60% of the dose is recovered in the feces unaltered. The preparation of a soluble formulation (i.e. by complexation with cyclodextrins) with improved bioavailability is the aim of this work. The inclusion of mitotane in methyl-ß-cyclodextrins was studied using both phase-solubility methods and NMR experiments. To elucidate the inclusion mechanism, o,p'-DDD was compared to its regioisomer (i.e. p,p'-DDD). It was demonstrated that two dimethyl-ß-cyclodextrins (DMßCD) can complex with the aromatic rings. From the phase-solubility diagrams, we observe that both cases are very different: K(1:1) is between 37 000 and 85 000 mol.l(-1), whereas K(1:2) is between 5.3 and 32 mol.l(-1). The NMR experiments confirmed the inclusion but it also gave an insight into the kinetics of the dissociation: the ortho-chloro moiety is in slow exchange on the NMR time scale, whereas the para-chloro moiety is in fast exchange rate. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Exploring academics' views on designs, methods, characteristics and outcomes of inclusive health research with people with intellectual disabilities: a modified Delphi study.

PubMed

Frankena, T K; Naaldenberg, J; Cardol, M; Meijering, J V; Leusink, G; van Schrojenstein Lantman-de Valk, H M J

2016-08-18

The British Medical Journal's (BMJ's) patient revolution strives for collaboration with patients in healthcare and health research. This paper studies collaboration with people with intellectual disabilities (ID) in health research, also known as inclusive health research. Currently, transparency and agreement among academics is lacking regarding its main aspects, preventing upscaling of the patient revolution. This study aims to gain agreement among academics on 3 aspects of inclusive health research for people with ID: (1) designs and methods, (2) most important characteristics and (3) outcomes. A Delphi study was conducted with academics with experience in inclusive (health) research and on people with ID. The study consisted of 2 sequential questionnaire rounds (n=24; n=17), followed by in-depth interviews (n=10). Academics agreed on (1) a collaborative approach to be most suitable to inclusive health research, (2) characteristics regarding the accessibility and facilitation of inclusive health research, and (3) several outcomes of inclusive health research for people with ID and healthcare. Other characteristics agreed on included: atmosphere, relationship, engagement, partnership and power. It was stressed that these characteristics ensure meaningful inclusion. Interviewed academics voiced the need for a tool supporting the facilitation and evaluation of inclusive health research. There was ambiguity as to what this tool should comprise and the extent to which it was possible to capture the complex process of inclusive health research. This study underlines the need for transparency, facilitation and evaluation of inclusive health research. The need for in-depth interviews after 2 Delphi rounds underlines its complexity and context dependence. To increase process transparency, future research should focus on gaining insight into inclusive health research in its context. A tool could be developed to facilitate and evaluate inclusive health research. This tool will be partially applicable to participatory research in general and thereby upscale the patient revolution. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

IC-tagged proteins are able to interact with each other and perform complex reactions when integrated into muNS-derived inclusions.

PubMed

Brandariz-Nuñez, Alberto; Otero-Romero, Iria; Benavente, Javier; Martinez-Costas, Jose M

2011-09-20

We have recently developed a versatile tagging system (IC-tagging) that causes relocation of the tagged proteins to ARV muNS-derived intracellular globular inclusions. In the present study we demonstrate (i) that the IC-tag can be successfully fused either to the amino or carboxyl terminus of the protein to be tagged and (ii) that IC-tagged proteins are able to interact between them and perform complex reactions that require such interactions while integrated into muNS inclusions, increasing the versatility of the IC-tagging system. Also, our studies with the DsRed protein add some light on the structure/function relationship of the evolution of DsRed chromophore. Copyright © 2011 Elsevier B.V. All rights reserved.

Development and Optimization of Dispersible Tablet of Bacopa monnieri with Improved Functionality for Memory Enhancement.

PubMed

Thakkar, Vaishali Tejas; Deshmukh, Amol; Hingorani, Lal; Juneja, Payal; Baldaniya, Lalji; Patel, Asha; Pandya, Tosha; Gohel, Mukesh

2017-01-01

The Bacopa monnieri is traditional Ayurvedic medicine, and reported for memory-enhancing effects. The Bacoside is poorly soluble, bitter in taste and responsible for the memory enhancement action. Memory enhancer is commonly prescribed for children or elder people. Poor solubility, patient compliance and bitterness were a major driving force to develop taste masked β-cyclodextrin complex and dispersible tablets. The inclusion complex of Bacopa monnieri and β-cyclodextrin was prepared in different molar ratios of Bacopa monnieri by Co-precipitation method. Phase solubility study was conducted to evaluate the effect of β-cyclodextrin on aqueous solubility of Bacoside A. The characterization was determined by Fourier transformation infrared spectroscopy (FTIR),Differential scanning calorimetry (DSC) and X-ray diffraction study (XRD).Crospovidone and croscarmallose sodium were used as super disintigrant. The 3 2 full factorial design was adopted to investigate the influence of two superdisintegrants on the wetting time and disntegration time of the tablets. The result revels that molar ratio (1:4) of inclusion complex enhance 3-fold solubility. Full factorial design was successfully employed for the optimization of dispersible tablet of B. monnieri . The short-term accelerated stability study confirmed that high stability of B. monnieri in inclusion complex.

Characterization of inclusion complexes of organic ions with hydrophilic hosts by ion transfer voltammetry with solvent polymeric membranes.

PubMed

Olmos, José Manuel; Laborda, Eduardo; Ortuño, Joaquín Ángel; Molina, Ángela

2017-03-01

The quantitative characterization of inclusion complexes formed in aqueous phase between organic ions and hydrophilic hosts by ion-transfer voltammetry with solvent polymeric membrane ion sensors is studied, both in a theoretical and experimental way. Simple analytical solutions are presented for the determination of the binding constant of the complex from the variation with the host concentration of the electrochemical signal. These solutions are valid for any voltammetric technique and for solvent polymeric membrane ion sensors comprising one polarisable interface (1PI) and also, for the first time, two polarisable interfaces (2PIs). Suitable experimental conditions and data analysis procedures are discussed and applied to the study of the interactions of a common ionic liquid cation (1-octyl-3-metyl-imidazolium) and an ionisable drug (clomipramine) with two hydrophilic cyclodextrins: α-cyclodextrin and 2-hydroxypropyl-β-cyclodextrin. The experimental study is performed via square wave voltammetry with 2PIs and 1PI solvent polymeric membranes and in both cases the electrochemical experiments enable the detection of inclusion complexes and the determination of the corresponding binding constant. Copyright © 2016 Elsevier B.V. All rights reserved.

New ethanol and propylene glycol free gel formulations containing a minoxidil-methyl-β-cyclodextrin complex as promising tools for alopecia treatment.

PubMed

Lopedota, Angela; Cutrignelli, Annalisa; Denora, Nunzio; Laquintana, Valentino; Lopalco, Antonio; Selva, Stefano; Ragni, Lorella; Tongiani, Serena; Franco, Massimo

2015-05-01

New topical totally aqueous formulations that improve the low water solubility of minoxidil and realize an adequate permeability of drug in the skin are proposed. These formulations are lacking in propylene glycol and alcohol that are the principal irritant ingredients present in minoxidil commercial solutions. In order to enhance poor water solubility of minoxidil randomly methyl-β-cyclodextrin was used, and four hydrogels such as, calcium alginate, sodium alginate, carbopol 934 and hydroxyethylcellulose were utilized to ensure a prolonged time of contact with the scalp. The inclusion complex minoxidil/methyl-β-cyclodextrin with a molar ratio 1:1 was obtained by freeze drying and evaluated by NMR, FT-IR and DSC analysis. An apparent stability constant of formed inclusion complex was calculated by phase solubility diagram and its value was 400 M(-1). The solid inclusion complex was used to prepare gel formulations with similar dose to minoxidil commercial solution. The gels were evaluated for various technological parameters including rheological behavior, in vitro drug release and ex vivo permeation through pig skin. The best performance was observed for the calcium alginate formulation.

Modified β-Cyclodextrin Inclusion Complex to Improve the Physicochemical Properties of Albendazole. Complete In Vitro Evaluation and Characterization

PubMed Central

García, Agustina; Leonardi, Darío; Salazar, Mario Oscar; Lamas, María Celina

2014-01-01

The potential use of natural cyclodextrins and their synthetic derivatives have been studied extensively in pharmaceutical research and development to modify certain properties of hydrophobic drugs. The ability of these host molecules of including guest molecules within their cavities improves notably the physicochemical properties of poorly soluble drugs, such as albendazole, the first chosen drug to treat gastrointestinal helminthic infections. Thus, the aim of this work was to synthesize a beta cyclodextrin citrate derivative, to analyze its ability to form complexes with albendazole and to evaluate its solubility and dissolution rate. The synthesis progress of the cyclodextrin derivative was followed by electrospray mass spectrometry and the acid-base titration of the product. The derivative exhibited an important drug affinity. Nuclear magnetic resonance experiments demonstrated that the tail and the aromatic ring of the drug were inside the cavity of the cyclodextrin derivative. The inclusion complex was prepared by spray drying and full characterized. The drug dissolution rate displayed exceptional results, achieving 100% drug release after 20 minutes. The studies indicated that the inclusion complex with the cyclodextrin derivative improved remarkably the physicochemical properties of albendazole, being a suitable excipient to design oral dosage forms. PMID:24551084

Stable Magnesium Isotope Variation in Melilite Mantle of Allende Type B1 CAI EK 459-5-1

NASA Technical Reports Server (NTRS)

Kerekgyarto, A. G.; Jeffcoat, C. R.; Lapen, T. J.; Andreasen, R.; Righter, M.; Ross, D. K.

2014-01-01

Ca-Al-rich inclusions (CAIs) are the earliest formed crystalline material in our solar system and they record early Solar System processes. Here we present petrographic and delta Mg-25 data of melilite mantles in a Type B1 CAI that records early solar nebular processes.

Cathodoluminescence, fluid inclusion and stable C-O isotope study of tectonic breccias from thrusting plane of a thin-skinned calcareous nappe

NASA Astrophysics Data System (ADS)

Milovský, Rastislav; van den Kerkhof, Alfons; Hoefs, Jochen; Hurai, Vratislav; Prochaska, Walter

2012-03-01

Basal hydraulic breccias of alpine thin-skinned Muráň nappe were investigated by means of cathodoluminescence petrography, stable isotope geochemistry and fluid inclusions analysis. Our study reveals an unusual dynamic fluid regime along basal thrust plane during final episode of the nappe emplacement over its metamorphic substratum. Basal thrusting fluids enriched in 18O, silica, alumina, alkalies and phosphates were generated in the underlying metamorphosed basement at epizonal conditions corresponding to the temperatures of 400-450°C. The fluids fluxed the tectonized nappe base, leached evaporite-bearing formations in hangingwall, whereby becoming oversaturated with sulphates and chlorides. The fluids further modified their composition by dedolomitization and isotopic exchange with the host carbonatic cataclasites. Newly formed mineral assemblage of quartz, phlogopite, albite, potassium feldspar, apatite, dravite tourmaline and anhydrite precipitated from these fluids on cooling down to 180-200°C. Finally, the cataclastic mush was cemented by calcite at ambient anchizonal conditions. Recurrent fluid injections as described above probably enhanced the final motion of the Muráň nappe.

Inclusion bodies of fuculose-1-phosphate aldolase as stable and reusable biocatalysts.

PubMed

Sans, Cristina; García-Fruitós, Elena; Ferraz, Rosa M; González-Montalbán, Núria; Rinas, Ursula; López-Santín, Josep; Villaverde, Antonio; Álvaro, Gregorio

2012-01-01

Fuculose-1-phosphate aldolase (FucA) has been produced in Escherichia coli as active inclusion bodies (IBs) in batch cultures. The activity of insoluble FucA has been modulated by a proper selection of producing strain, culture media, and process conditions. In some cases, when an optimized defined medium was used, FucA IBs were more active (in terms of specific activity) than the soluble protein version obtained in the same process with a conventional defined medium, supporting the concept that solubility and conformational quality are independent protein parameters. FucA IBs have been tested as biocatalysts, either directly or immobilized into Lentikat beads, in an aldolic reaction between DHAP and (S)-Cbz-alaninal, obtaining product yields ranging from 65 to 76%. The production of an active aldolase as IBs, the possibility of tailoring IBs properties by both genetic and process approaches, and the reusability of IBs by further entrapment in appropriate matrices fully support the principle of using self-assembled enzymatic clusters as tunable mechanically stable and functional biocatalysts. Copyright © 2012 American Institute of Chemical Engineers (AIChE).

Supramolecular Inclusion in Cyclodextrins: A Pictorial Spectroscopic Demonstration

ERIC Educational Resources Information Center

Haldar, Basudeb; Mallick, Arabinda; Chattopadhyay, Nitin

2008-01-01

A spectroscopic experiment is presented that reveals that the hydrophobically end-modified water-soluble polymeric fluorophore, pyrene end-capped poly(ethylene oxide) (PYPY), interacts differently with [alpha], [beta], and [gamma]-cyclodextrins (CD) to form supramolecular inclusion complexes. The emission spectrum of PYPY in aqueous solution shows…

Molecular Modeling and Physicochemical Properties of Supramolecular Complexes of Limonene with α- and β-Cyclodextrins.

PubMed

Dos Passos Menezes, Paula; Dos Santos, Polliana Barbosa Pereira; Dória, Grace Anne Azevedo; de Sousa, Bruna Maria Hipólito; Serafini, Mairim Russo; Nunes, Paula Santos; Quintans-Júnior, Lucindo José; de Matos, Iara Lisboa; Alves, Péricles Barreto; Bezerra, Daniel Pereira; Mendonça Júnior, Francisco Jaime Bezerra; da Silva, Gabriel Francisco; de Aquino, Thiago Mendonça; de Souza Bento, Edson; Scotti, Marcus Tullius; Scotti, Luciana; de Souza Araujo, Adriano Antunes

2017-02-01

This study evaluated three different methods for the formation of an inclusion complex between alpha- and beta-cyclodextrin (α- and β-CD) and limonene (LIM) with the goal of improving the physicochemical properties of limonene. The study samples were prepared through physical mixing (PM), paste complexation (PC), and slurry complexation (SC) methods in the molar ratio of 1:1 (cyclodextrin:limonene). The complexes prepared were evaluated with thermogravimetry/derivate thermogravimetry, infrared spectroscopy, X-ray diffraction, complexation efficiency through gas chromatography/mass spectrometry analyses, molecular modeling, and nuclear magnetic resonance. The results showed that the physical mixing procedure did not produce complexation, but the paste and slurry methods produced inclusion complexes, which demonstrated interactions outside of the cavity of the CDs. However, the paste obtained with β-cyclodextrin did not demonstrate complexation in the gas chromatographic technique because, after extraction, most of the limonene was either surface-adsorbed by β-cyclodextrin or volatilized during the procedure. We conclude that paste complexation and slurry complexation are effective and economic methods to improve the physicochemical character of limonene and could have important applications in pharmacological activities in terms of an increase in solubility.

Efficient Red-Emitting Platinum Complex with Long Operational Stability.

PubMed

Fleetham, Tyler; Li, Guijie; Li, Jian

2015-08-05

A tetradentate cyclometalated Pt(II) complex, PtN3N-ptb, was developed as an emissive dopant for stable and efficient red phosphorescent OLEDs. Devices employing PtN3N-ptb in electrochemically stable device architectures achieved long operational lifetimes with estimated LT97, of over 600 h at luminances of 1000 cd/m(2). Such long operational lifetimes were achieved utilizing only literature reported host, transporting and blocking materials with known molecular structures. Additionally, a thorough study of the effects of various host and transport materials on the efficiency, turn on voltage, and stability of the devices was carried out. Ultimately, maximum forward viewing EQEs as high as 21.5% were achieved, demonstrating that Pt(II) complexes can act as stable and efficient dopants with operational lifetimes comparable or superior to those of the best literature-reported Ir(III) complexes.

Spectral and theoretical study on complexation of sulfamethoxazole with β- and HPβ-cyclodextrins in binary and ternary systems

NASA Astrophysics Data System (ADS)

Varghese, Beena; Suliman, FakhrEldin O.; Al-Hajri, Aalia; Al Bishri, Nahed Surur S.; Al-Rwashda, Nathir

2018-02-01

The inclusion complexes of sulfamethoxazole (SMX) with β-cyclodextrin (βCD) and (2-hydroxypropyl) β-cyclodextrin (HPβCD) were prepared. Fluorescence spectroscopy and electrospray mass spectrometry, ESI-MS, were used to investigate and characterize the inclusion complexation of SMX with cyclodextrins in solutions. Whereas in the solid state the complexes were characterized by Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD) and Raman techniques. Enhanced twisted intramolecular charge transfer (TICT), emission as well as local excited (LE) bands were observed upon addition of HPβCD indicate that SMX enters deeper into the cyclodextrins cavity. The stoichiometries and association constants of these complexes have been determined by monitoring the fluorescence data. The effect of presence of ternary components like arginine and cysteine on the complexation efficiency of SMX with cyclodextrins was investigated. Molecular Dynamic simulations were also performed to shed an atomistic insight into the complexation mechanism. The results obtained showed that complexes of SMX with both cyclodextrins are stabilized in aqueous media by strong hydrogen bonding interactions.

Study of base pair mutations in proline-rich homeodomain (PRH)-DNA complexes using molecular dynamics.

PubMed

Jalili, Seifollah; Karami, Leila; Schofield, Jeremy

2013-06-01

Proline-rich homeodomain (PRH) is a regulatory protein controlling transcription and gene expression processes by binding to the specific sequence of DNA, especially to the sequence 5'-TAATNN-3'. The impact of base pair mutations on the binding between the PRH protein and DNA is investigated using molecular dynamics and free energy simulations to identify DNA sequences that form stable complexes with PRH. Three 20-ns molecular dynamics simulations (PRH-TAATTG, PRH-TAATTA and PRH-TAATGG complexes) in explicit solvent water were performed to investigate three complexes structurally. Structural analysis shows that the native TAATTG sequence forms a complex that is more stable than complexes with base pair mutations. It is also observed that upon mutation, the number and occupancy of the direct and water-mediated hydrogen bonds decrease. Free energy calculations performed with the thermodynamic integration method predict relative binding free energies of 0.64 and 2 kcal/mol for GC to AT and TA to GC mutations, respectively, suggesting that among the three DNA sequences, the PRH-TAATTG complex is more stable than the two mutated complexes. In addition, it is demonstrated that the stability of the PRH-TAATTA complex is greater than that of the PRH-TAATGG complex.

Encapsulating fatty acid esters of bioactive compounds in starch

NASA Astrophysics Data System (ADS)

Lay Ma, Ursula Vanesa

Interest in the use of many bioactive compounds in foods is growing in large part because of the apparent health benefits of these molecules. However, many of these compounds can be easily degraded during processing, storage, or their passage through the gastrointestinal tract before reaching the target site. In addition, they can be bitter, acrid, or astringent, which may negatively affect the sensory properties of the product. Encapsulation of these molecules may increase their stability during processing, storage, and in the gastrointestinal tract, while providing controlled release properties. The ability of amylose to form inclusion complexes and spherulites while entrapping certain compounds has been suggested as a potential method for encapsulation of certain molecules. However, complex formation and spherulitic crystallization are greatly affected by the type of inclusion molecules, type of starch, and processing conditions. The objectives of the present investigation were to: (a) study the effect of amylose, amylopectin, and intermediate material on spherulite formation and its microstructure; (b) investigate the formation of amylose and high amylose starch inclusion complexes with ascorbyl palmitate, retinyl palmitate, and phytosterol esters; (c) evaluate the ability of spherulites to form in the presence of fatty acid esters and to entrap ascorbyl palmitate, retinyl palmitate, and phytosterol esters; and (d) evaluate the effect of processing conditions on spherulite formation and fatty acid ester entrapment. Higher ratios of linear to branched molecules resulted in the formation of more and rounder spherulites with higher heat stability. In addition to the presence of branches, it appears that spherulitic crystallization is also affected by other factors, such as degree of branching, chain length, and chain length distribution. Amylose and Hylon VII starch formed inclusion complexes with fatty acid esters of ascorbic acid, retinol, or phytosterols. However, only retinyl palmitate formed a complex with amylopectin. In general, ascorbyl palmitate resulted in the highest complexation, followed by retinyl palmitate and phytosterol ester. The presence of native lipids in Hylon VII starch did not inhibit complex formation. On the contrary, native lipids appear to increase the complexation yield and thermal stability of the starch-fatty acid ester inclusion complexes, possibly due to the formation of ternary complexes. From the three fatty acid esters studied, only ascorbyl palmitate was entrapped in starch spherulites. Various structures including round spherulites, various sizes of torus-shape spherulites, non-spherulitic birefringent and non-birefringent particles, "balloon" morphologies, and gel-like material were formed depending on processing conditions. However, only the torus-shape spherulites, and some non-spherulitic birefringent and non-birefringent particles showed ascorbyl palmitate entrapment. The % yield of the precipitate increased with higher % of added Hylon VII, and decreased with higher heating temperature and faster cooling rates. The amount of entrapped ascorbyl palmitate in the starch precipitate seems to be governed by the amount of this compound added during processing. This study showed that starch can form inclusion complexes with fatty acid esters which may be used for the delivery of certain bioactive molecules. In addition, encapsulation of fatty acid esters in starch spherulites may be a good potential delivery system for water soluble bioactive molecules. However, further research is necessary to gain a better understanding of the type of molecules that can be entrapped in starch spherulites, and the factors affecting spherulitic crystallization and bioactive compound entrapment.

Including Psychology in Inclusive Pedagogy: Enriching the Dialogue?

ERIC Educational Resources Information Center

Kershner, Ruth

2016-01-01

Inclusive education is a complex field of study and practice that requires good communication and dialogue between all involved. Psychology has to some extent been marginalised in these educational dialogues. This is, in part, due to psychology's perceived heritage in the standardised testing that has been used to support the educational…

Efficacy of Peer Support Arrangements to Increase Peer Interaction and AAC Use

ERIC Educational Resources Information Center

Biggs, Elizabeth E.; Carter, Erik W.; Gustafson, Jenny

2017-01-01

Supporting interaction in inclusive settings between students with complex communication needs (CCN) and their peers requires careful planning and support. We used a multiple-probe-across-participants design to investigate the efficacy of collaborative planning and peer support arrangements to increase peer interaction in inclusive classrooms.…

Outgassed water on Mars - Constraints from melt inclusions in SNC meteorites

NASA Technical Reports Server (NTRS)

Mcsween, Harry Y., Jr.; Harvey, Ralph P.

1993-01-01

The SNC (shergottite-nakhlite-chassignite) meteorites, thought to be igneous rocks from Mars, contain melt inclusions trapped at depth in early-formed crystals. Determination of the pre-eruptive water contents of SNC parental magmas from calculations of the solidification histories of these amphibole-bearing inclusions indicates that Martian magmas commonly contained 1.4 percent water by weight. When combined with an estimate of the volume of igneous materials on Mars, this information suggests that the total amount of water outgassed since 3.9 billion years ago corresponds to global depths on the order of 200 meters. This value is significantly higher than previous geochemical estimates but lower than estimates based on erosion by floods. These results imply a wetter Mars interior than has been previously thought and support suggestions of significant outgassing before formation of a stable crust or heterogeneous accretion of a veneer of cometary matter.

Encapsulation of boswellic acid with β- and hydroxypropyl-β-cyclodextrin: Synthesis, characterization, in vitro drug release and molecular modelling studies

NASA Astrophysics Data System (ADS)

Tambe, Amruta; Pandita, Nancy; Kharkar, Prashant; Sahu, Niteshkumar

2018-02-01

Boswellic acids (BAs) are a group of pentacyclic triterpenes present in gum-resin of Boswellia serrata. They are well known for their anti-inflammatory, hypolipidemic, immunomodulatory and anti-tumor activity, but they have poor aqueous solubility and limited bioavailability. In order to enhance their aqueous solubility, inclusion complexes of BAs with β-cyclodextrin (β-CD) and hydroxypropyl-β-cyclodextrin (HP-β-CD) were synthesized and their drug release profiles were studied. Molecular associations of β-CD and HP-β-CD with BAs were investigated by phase solubility studies. The stability constants were found to be 380.2 and 145.9 M-1 for BA: β-CD and BA: HP-β-CD inclusion complexes, respectively with AN- type curve. BA: β-CD and BA: HP-β-CD inclusion complexes were synthesized using kneading (KN), co-precipitation (CP) and solvent evaporation (SE) methods in 1:1 as well as 1:2 ratios. Further these were characterized by Fourier transform infrared (FTIR) spectrophotometry, Powder X-ray Diffraction (P-XRD) and Differential scanning calorimetric (DSC) analysis. FTIR analysis showed shifting of frequencies in complexes as compared to CDs and BAs. P-XRD data obtained for BA: β-CD complexes synthesized by CP and SE methods showed amorphous pattern. Also, DSC analysis showed a change in thermal behaviour for synthesized complexes. In vitro drug release studies of BA: β-CD complexes showed enhanced release with 1:2 complexes than 1:1 complexes at pH 1.2 and pH 6.8. Similarly, drug release enhancement was observed more with BA: HP-β-CD complexes in 1:2 ratio than 1:1. To understand the interaction of BAs with CD cavity molecular modelling studies were performed which favored 1:2 complex formation over 1:1 complexes. The study thus highlights that CDs can be used for solubility and dissolution enhancement of BAs.

Quantum chemical studies on hypothetical Fischer type Mo(CO)5[C(OEt)Me] and Mo(CO)5[C(OMe)Et] carbene complexes

NASA Astrophysics Data System (ADS)

Gövdeli, Nezafet; Karakaş, Duran

2018-07-01

Quantum chemical calculations at B3LYP/LANL2DZ/6-31G(d) level were made on anti-eclipsed, anti-staggered, syn-eclipsed, syn-staggered conformers of hypothetical Fischer type Mo(CO)5[C(OEt)Me] and Mo(CO)5[C(OMe)Et] carbene complexes in the gas phase. The most stable conformer of the complexes was found to be anti-staggered according to the total energy values calculated at given level. Structural parameters, vibration spectra, charge distributions, molecular orbital energy diagrams, contour diagrams of frontier orbitals, molecular electrostatic potential maps and some electronic structure descriptors were obtained for the most stable conformers. NMR spectra of the most stable conformers were calculated at GIAO/B3LYP/LANL2DZ level. The most stable conformer geometry was found to be distorted octahedral. IR and NMR spectra of the complexes are consistent with their geometry. HOMOs of the complexes were found to be center-atomic character and LUMOs were carbene-carbon character. From the calculated charge analysis and molecular electrostatic potential maps, it is found that carbene-carbon acts as electrofil and metal center nucleophile. It is suggested that the catalytic properties of the carbene complexes may be due to the fact that the carbene-carbon behave as electrophile and metal center nucleophile. Some electronic structure descriptors of the complexes were calculated and the molecular properties were estimated.

Binding of 3O2 and 1O2 to dyes used in photodynamic therapy in gas phase and aqueous media

NASA Astrophysics Data System (ADS)

Kushwaha, P. S.; Mishra, P. C.

Density functional theory (DFT) was employed at the B3LYP/6-31+G* level to study complexes of 1O2 and 3O2 with the dye molecules proflavine, methylene blue, and acridine orange, which are useful in photodynamic therapy. It was found that the most stable complex between 1O2 and proflavine are formed when 1O2 is located above the central ring, while the most stable complex between 1O2 and methylene blue is formed when 1O2 is located above the molecular plane, but not above any of the rings, near the sulfur atom. 1O2 can make a stable complex with acridine orange, as it is located above the outer ring of the dye. The binding energies of the complexes of 1O2 with all three dyes are enhanced considerably in going from gas phase to aqueous media. The complexes of 3O2 with the dyes will be unstable in all cases, while those of 1O2 with the same will be quite stable and will not be dissociated due to thermal fluctuations at room temperature. In the complexes of 1O2 and 3O2 with the dyes, charge transfer occurs from the dyes to the O2 moiety, the amount of charge transfer being much more to 1O2 than to 3O2 in each case.

Analytical techniques for characterization of cyclodextrin complexes in the solid state: A review.

PubMed

Mura, Paola

2015-09-10

Cyclodextrins are cyclic oligosaccharides able to form inclusion complexes with a variety of hydrophobic guest molecules, positively modifying their physicochemical properties. A thorough analytical characterization of cyclodextrin complexes is of fundamental importance to provide an adequate support in selection of the most suitable cyclodextrin for each guest molecule, and also in view of possible future patenting and marketing of drug-cyclodextrin formulations. The demonstration of the actual formation of a drug-cyclodextrin inclusion complex in solution does not guarantee its existence also in the solid state. Moreover, the technique used to prepare the solid complex can strongly influence the properties of the final product. Therefore, an appropriate characterization of the drug-cyclodextrin solid systems obtained has also a key role in driving in the choice of the most effective preparation method, able to maximize host-guest interactions. The analytical characterization of drug-cyclodextrin solid systems and the assessment of the actual inclusion complex formation is not a simple task and involves the combined use of several analytical techniques, whose results have to be evaluated together. The objective of the present review is to present a general prospect of the principal analytical techniques which can be employed for a suitable characterization of drug-cyclodextrin systems in the solid state, evidencing their respective potential advantages and limits. The applications of each examined technique are described and discussed by pertinent examples from literature. Copyright © 2015 Elsevier B.V. All rights reserved.

The comparison of different daidzein-PLGA nanoparticles in increasing its oral bioavailability.

PubMed

Ma, Yiran; Zhao, Xinyi; Li, Jian; Shen, Qi

2012-01-01

The aim of this research was to increase the oral bioavailability of daidzein by the formulations of poly(lactic-co-glycolic) acid (PLGA) nanoparticles loaded with daidzein. Amongst the various traditional and novel techniques of preparing daidzein-loaded PLGA nanoparticles, daidzein-loaded phospholipid complexes PLGA nanoparticles and daidzein-loaded cyclodextrin inclusion complexes PLGA nanoparticles were selected. The average drug entrapment efficiency, particle size, and zeta potential of daidzein-loaded phospholipid complexes PLGA nanoparticles and daidzein-loaded cyclodextrin inclusion complexes PLGA nanoparticles were 81.9% ± 5%, 309.2 ± 14.0 nm, -32.14 ± 2.53 mV and 83.2% ± 7.2%, 323.2 ± 4.8 nm, -18.73 ± 1.68 mV, respectively. The morphological characterization of nanoparticles was observed with scanning electron microscopy by stereological method and the physicochemical state of nanoparticles was valued by differential scanning calorimetry. The in vitro drug-release profile of both nanoparticle formulations fitted the Weibull dynamic equation. Pharmacokinetic studies demonstrated that after oral administration of daidzein-loaded phospholipid complexes PLGA nanoparticles and daidzein-loaded cyclodextrin inclusion complexes PLGA nanoparticles to rats at a dose of 10 mg/kg, relative bioavailability was enhanced about 5.57- and 8.85-fold, respectively, compared to daidzein suspension as control. These results describe an effective strategy for oral delivery of daidzein-loaded PLGA nanoparticles and might provide a fresh approach to enhancing the bioavailability of drugs with poor lipophilic and poor hydrophilic properties.

The comparison of different daidzein-PLGA nanoparticles in increasing its oral bioavailability

PubMed Central

Ma, Yiran; Zhao, Xinyi; Li, Jian; Shen, Qi

2012-01-01

The aim of this research was to increase the oral bioavailability of daidzein by the formulations of poly(lactic-co-glycolic) acid (PLGA) nanoparticles loaded with daidzein. Amongst the various traditional and novel techniques of preparing daidzein-loaded PLGA nanoparticles, daidzein-loaded phospholipid complexes PLGA nanoparticles and daidzein-loaded cyclodextrin inclusion complexes PLGA nanoparticles were selected. The average drug entrapment efficiency, particle size, and zeta potential of daidzein-loaded phospholipid complexes PLGA nanoparticles and daidzein-loaded cyclodextrin inclusion complexes PLGA nanoparticles were 81.9% ± 5%, 309.2 ± 14.0 nm, −32.14 ± 2.53 mV and 83.2% ± 7.2%, 323.2 ± 4.8 nm, −18.73 ± 1.68 mV, respectively. The morphological characterization of nanoparticles was observed with scanning electron microscopy by stereological method and the physicochemical state of nanoparticles was valued by differential scanning calorimetry. The in vitro drug-release profile of both nanoparticle formulations fitted the Weibull dynamic equation. Pharmacokinetic studies demonstrated that after oral administration of daidzein-loaded phospholipid complexes PLGA nanoparticles and daidzein-loaded cyclodextrin inclusion complexes PLGA nanoparticles to rats at a dose of 10 mg/kg, relative bioavailability was enhanced about 5.57- and 8.85-fold, respectively, compared to daidzein suspension as control. These results describe an effective strategy for oral delivery of daidzein-loaded PLGA nanoparticles and might provide a fresh approach to enhancing the bioavailability of drugs with poor lipophilic and poor hydrophilic properties. PMID:22346351

Genesis of the Sb-W-Au deposits at Ixtahuacan, Guatemala: evidence from fluid inclusions and stable isotopes

NASA Astrophysics Data System (ADS)

Guillemette, N.; Williams-Jones, A. E.

1993-06-01

The Ixtahuacan Sb-W deposits are hosted by upper Pennsylvanian to Permian metasedimentary rocks of the central Cordillera of Guatemala. The deposits consist of gold-bearing arsenopyrite, stibnite and scheelite. Arsenopyrite and scheelite are early in the paragenesis, occurring as disseminations in pyritiferous black shale/sandstone and in argillaceous limestone, respectively. Some stibnite is disseminated, but the bulk of the stibnite occurs as massive stratabound lenses in black shales and in quartz-ankerite veins and breccias, locally containing scheelite. Microthermometric measurements on fluid inclusions in quartz and scheelite point to a low temperature (160 190°C) and low to moderate salinity (5 15 wt% NaCl eq.) aqueous ore fluid. Abundant vapour-rich inclusions suggest that the fluid boiled. Carbon dioxide was produced locally as a result of interaction of the aqueous fluid with the argillaceous limestone. Bulk leaching experiments and SEM-EDS analyses of decrepitated fluid inclusion residues indicate that the ore-bearing solution was NaCl-dominated. The δ18O values of quartz, ankerite and scheelite from mineralized veins range from 19.7 to 20.5‰, 18.1 to 20.0‰ and 7.0 to 8.4‰ respectively. The average temperature calculated from quartz-scheelite oxygen isotopic fractionation is 170°C. The oxygen isotopic composition of the fluid, interpreted to have been in equilibrium with these minerals, ranged from 5.7 to 7.6‰, and is considered to represent an evolved meteoric water. Diagenetic or syngenetic pyrite has a sulphur isotopic composition of 0.5±0.3‰ which is consistent with bacterial reduction of sulphate. The δ34S values of arsenopyrite and stibnite range from -2.8 to 2.0‰ and -2.7 to -2.3‰ respectively, and are though to reflect sulphur derived from pyrite. The Ixtahuacan deposits are interpreted to have formed at low temperature (<200°C) and a depth of a few hundred metres from a low fO2 (10-49-10-57), high pH (7 8) fluid. Arsenic was probably transported as arsenious acid, antimony and gold as thio-complexes and tungsten as the complex HWO{4/-}. A model is proposed in which a meteoric fluid, heated by a felsic intrusion at depth, was focused to shallow levels along faults. The interaction of the fluid with pyritiferous beds caused the deposition of arsenopyrite as a result of sulphidation and/or decreasing fO2; gold probably co-precipitated with As or was adsorbed onto the arsenopyrite. The precipitation of stibnite was caused by boiling. Scheelite deposited in response to the increase in Ca2+ activity which accompanied interaction of the ore fluid with the argillaceous limestones.

Phase behaviour and structure of stable complexes of oppositely charged polyelectrolytes

NASA Astrophysics Data System (ADS)

Mengarelli, V.; Auvray, L.; Zeghal, M.

2009-03-01

We study the formation and structure of stable electrostatic complexes between oppositely charged polyelectrolytes, a long polymethacrylic acid and a shorter polyethylenimine, at low pH, where the polyacid is weakly charged. We explore the phase diagram as a function of the charge and concentration ratio of the constituents. In agreement with theory, turbidity and ζ potential measurements show two distinct regimes of weak and strong complexation, which appear successively as the pH is increased and are separated by a well-defined limit. Weak complexes observed by neutron scattering and contrast matching have an open, non-compact structure, while strong complexes are condensed.

Proteolytic digestion of bacterial inclusion body proteins during dynamic transition between soluble and insoluble forms.

PubMed

Carrió, M M; Corchero, J L; Villaverde, A

1999-09-14

Inclusion bodies formed by two closely related hybrid proteins, namely VP1LAC and LACVP1, have been compared during their building in Escherichia coli. Features of these proteins are determinant of aggregation rates and protein composition of the bodies, generating insoluble particles with distinguishable volume evolution. Interestingly, in LACVP1 and less perceptibly in VP1LAC bodies, an important fraction of the aggregated polypeptide is lost at a given stage of body construction. Stable degradation intermediates of the more fragile LACVP1 are concomitantly found embedded in the bodies. When recombinant protein synthesis is arrested in growing cells, the amount of aggregated protein drops while the amount of soluble protein undergoes a sudden rise before proteolysis. This indicates an architectural plasticity during the in vivo building of the studied inclusion bodies by a dynamic transition between soluble and insoluble forms of the recombinant proteins involved. During this transition, protease-sensitive polypeptides can suffer an efficient proteolytic attack and the resulting fragments further aggregate as inclusion body components.

Adding Complex Terrain and Stable Atmospheric Condition Capability to the OpenFOAM-based Flow Solver of the Simulator for On/Offshore Wind Farm Applications (SOWFA): Preprint

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

Churchfield, M. J.; Sang, L.; Moriarty, P. J.

This paper describes changes made to NREL's OpenFOAM-based wind plant aerodynamics solver such that it can compute the stably stratified atmospheric boundary layer and flow over terrain. Background about the flow solver, the Simulator for Off/Onshore Wind Farm Applications (SOWFA) is given, followed by details of the stable stratification/complex terrain modifications to SOWFA, along with somepreliminary results calculations of a stable atmospheric boundary layer and flow over a simply set of hills.

Adding Complex Terrain and Stable Atmospheric Condition Capability to the Simulator for On/Offshore Wind Farm Applications (SOWFA) (Presentation)

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

Churchfield, M. J.

This presentation describes changes made to NREL's OpenFOAM-based wind plant aerodynamics solver so that it can compute the stably stratified atmospheric boundary layer and flow over terrain. Background about the flow solver, the Simulator for Off/Onshore Wind Farm Applications (SOWFA) is given, followed by details of the stable stratification/complex terrain modifications to SOWFA, along with some preliminary results calculations of a stable atmospheric boundary layer and flow over a simple set of hills.

Dual fluorescence of N-phenylanthranilic acid: Effect of solvents, pH and beta-cyclodextrin.

PubMed

Rajendiran, N; Balasubramanian, T

2007-11-01

Spectral characteristics of N-phenylanthranilic acid (NPAA) have been studied in different solvents, pH and beta-cyclodextrin (beta-CD) and compared with anthranilic acid (2-aminobenzoic acid, 2ABA). In all solvents a dual fluorescence is observed in NPAA, whereas 2ABA gives single emission. Combining the results observed in the absorption, fluorescence emission and fluorescence excitation spectra, it is found that strong intramolecular hydrogen bonding (IHB) interactions present in NPAA molecule. The inclusion complex of NPAA with beta-CD is analysed by UV-vis, fluorimetry, FT-IR, (1)H NMR, scanning electron microscope and AM 1 method. The above spectral studies show that NPAA forms a 1:1 inclusion complex with beta-CD and COOH group present in the beta-CD cavity. A mechanism is proposed to explain the inclusion process.

Dual fluorescence of N-phenylanthranilic acid: Effect of solvents, pH and β-cyclodextrin

NASA Astrophysics Data System (ADS)

Rajendiran, N.; Balasubramanian, T.

2007-11-01

Spectral characteristics of N-phenylanthranilic acid (NPAA) have been studied in different solvents, pH and β-cyclodextrin (β-CD) and compared with anthranilic acid (2-aminobenzoic acid, 2ABA). In all solvents a dual fluorescence is observed in NPAA, whereas 2ABA gives single emission. Combining the results observed in the absorption, fluorescence emission and fluorescence excitation spectra, it is found that strong intramolecular hydrogen bonding (IHB) interactions present in NPAA molecule. The inclusion complex of NPAA with β-CD is analysed by UV-vis, fluorimetry, FT-IR, 1H NMR, scanning electron microscope and AM 1 method. The above spectral studies show that NPAA forms a 1:1 inclusion complex with β-CD and COOH group present in the β-CD cavity. A mechanism is proposed to explain the inclusion process.

Symmetric and Asymmetric Tendencies in Stable Complex Systems

PubMed Central

Tan, James P. L.

2016-01-01

A commonly used approach to study stability in a complex system is by analyzing the Jacobian matrix at an equilibrium point of a dynamical system. The equilibrium point is stable if all eigenvalues have negative real parts. Here, by obtaining eigenvalue bounds of the Jacobian, we show that stable complex systems will favor mutualistic and competitive relationships that are asymmetrical (non-reciprocative) and trophic relationships that are symmetrical (reciprocative). Additionally, we define a measure called the interdependence diversity that quantifies how distributed the dependencies are between the dynamical variables in the system. We find that increasing interdependence diversity has a destabilizing effect on the equilibrium point, and the effect is greater for trophic relationships than for mutualistic and competitive relationships. These predictions are consistent with empirical observations in ecology. More importantly, our findings suggest stabilization algorithms that can apply very generally to a variety of complex systems. PMID:27545722

Symmetric and Asymmetric Tendencies in Stable Complex Systems.

PubMed

Tan, James P L

2016-08-22

A commonly used approach to study stability in a complex system is by analyzing the Jacobian matrix at an equilibrium point of a dynamical system. The equilibrium point is stable if all eigenvalues have negative real parts. Here, by obtaining eigenvalue bounds of the Jacobian, we show that stable complex systems will favor mutualistic and competitive relationships that are asymmetrical (non-reciprocative) and trophic relationships that are symmetrical (reciprocative). Additionally, we define a measure called the interdependence diversity that quantifies how distributed the dependencies are between the dynamical variables in the system. We find that increasing interdependence diversity has a destabilizing effect on the equilibrium point, and the effect is greater for trophic relationships than for mutualistic and competitive relationships. These predictions are consistent with empirical observations in ecology. More importantly, our findings suggest stabilization algorithms that can apply very generally to a variety of complex systems.

Genome-Wide Analysis of Grain Yield Stability and Environmental Interactions in a Multiparental Soybean Population.

PubMed

Xavier, Alencar; Jarquin, Diego; Howard, Reka; Ramasubramanian, Vishnu; Specht, James E; Graef, George L; Beavis, William D; Diers, Brian W; Song, Qijian; Cregan, Perry B; Nelson, Randall; Mian, Rouf; Shannon, J Grover; McHale, Leah; Wang, Dechun; Schapaugh, William; Lorenz, Aaron J; Xu, Shizhong; Muir, William M; Rainey, Katy M

2018-02-02

Genetic improvement toward optimized and stable agronomic performance of soybean genotypes is desirable for food security. Understanding how genotypes perform in different environmental conditions helps breeders develop sustainable cultivars adapted to target regions. Complex traits of importance are known to be controlled by a large number of genomic regions with small effects whose magnitude and direction are modulated by environmental factors. Knowledge of the constraints and undesirable effects resulting from genotype by environmental interactions is a key objective in improving selection procedures in soybean breeding programs. In this study, the genetic basis of soybean grain yield responsiveness to environmental factors was examined in a large soybean nested association population. For this, a genome-wide association to performance stability estimates generated from a Finlay-Wilkinson analysis and the inclusion of the interaction between marker genotypes and environmental factors was implemented. Genomic footprints were investigated by analysis and meta-analysis using a recently published multiparent model. Results indicated that specific soybean genomic regions were associated with stability, and that multiplicative interactions were present between environments and genetic background. Seven genomic regions in six chromosomes were identified as being associated with genotype-by-environment interactions. This study provides insight into genomic assisted breeding aimed at achieving a more stable agronomic performance of soybean, and documented opportunities to exploit genomic regions that were specifically associated with interactions involving environments and subpopulations. Copyright © 2018 Xavier et al.

Flight-Like Optical Reference Cavity for GRACE Follow-On Laser Frequency Stabilization

NASA Technical Reports Server (NTRS)

Folkner, W. M.; deVine, G.; Klipstein, W. M.; McKenzie, K.; Spero, R.; Thompson, R.; Yu, N.; Stephens, M.; Leitch, J.; Pierce, R.;

Characterization of Albendazole-Randomly Methylated-β-Cyclodextrin Inclusion Complex and In Vivo Evaluation of Its Antihelmitic Activity in a Murine Model of Trichinellosis

PubMed Central

García, Agustina; Leonardi, Darío; Vasconi, María D.; Hinrichsen, Lucila I.; Lamas, María C.

2014-01-01

Albendazole is a benzimidazole carbamate extensively used in oral chemotherapy against intestinal parasites, due to its broad spectrum activity, good tolerance and low cost. However, the drug has the disadvantage of poor bioavailability due to its very low solubility in water; as a consequence, a very active area of research focuses on the development of new pharmaceutical formulations to increase its solubility, dissolution rate, and bioavailability. The primary objective of this study was to prepare randomly methylated β-cyclodextrins inclusion complexes to increase albendazole dissolution rate, in order to enhance its antiparasitic activity. This formulation therapeutic efficacy was contrasted with that of the pure drug by treating Trichinella spiralis infected mice during the intestinal phase of the parasite cycle, on days five and six post-infection. This protocol significantly decreased muscle larval burden measured in the parenteral stage on day 30 post-infection, when compared with the untreated control. Thus, it could be demonstrated that the inclusion complexes improve the in vivo therapeutic activity of albendazole. PMID:25406084

Dual responsive supramolecular hydrogel with electrochemical activity.

PubMed

Du, Ping; Liu, Jianghua; Chen, Guosong; Jiang, Ming

2011-08-02

Supramolecular materials with reversible responsiveness to environmental changes are of particular research interest in recent years. Inclusion complexation between cyclodextrin (CD) and ferrocene (Fc) is well-known and extensively studied because of its reversible association-dissociation controlled by the redox state of Fc. Although there are quite a few reported nanoscale materials incorporating this host-guest pair, polymeric hydrogels with electrochemical activity based on this interactive pair are still rare. Taking advantage of our previous reported hybrid inclusion complex (HIC) hydrogel structure, a new Fc-HIC was designed and obtained with β-CD-modified quantum dots as the core and Fc-ended diblock co-polymer p(DMA-b-NIPAM) as the shell, to achieve an electrochemically active hydrogel at elevated temperatures. Considering the two independent cross-linking strategies in the network structure, i.e., the interchain aggregation of pNIPAM and inclusion complexation between CD and Fc on the surface of the quantum dots, the hydrogel was fully thermo-reversible and its gel-sol transition was achieved after the addition of either an oxidizing agent or a competitive guest to Fc.

Self-Healing and Thermo-Responsive Dual-Crosslinked Alginate Hydrogels based on Supramolecular Inclusion Complexes

PubMed Central

Miao, Tianxin; Fenn, Spencer L.; Charron, Patrick N.; Oldinski, Rachael A.

2015-01-01

β-cyclodextrin (β-CD), with a lipophilic inner cavity and hydrophilic outer surface, interacts with a large variety of non-polar guest molecules to form non-covalent inclusion complexes. Conjugation of β-CD onto biomacromolecules can form physically-crosslinked hydrogel networks upon mixing with a guest molecule. Herein describes the development and characterization of self-healing, thermo-responsive hydrogels, based on host-guest inclusion complexes between alginate-graft-β-CD and Pluronic® F108 (poly(ethylene glycol)-b-poly(propylene glycol)-b-poly(ethylene glycol)). The mechanics, flow characteristics, and thermal response were contingent on the polymer concentrations, and the host-guest molar ratio. Transient and reversible physical crosslinking between host and guest polymers governed self-assembly, allowing flow under shear stress, and facilitating complete recovery of the material properties within a few seconds of unloading. The mechanical properties of the dual-crosslinked, multi-stimuli responsive hydrogels were tuned as high as 30 kPa at body temperature, and are advantageous for biomedical applications such as drug delivery and cell transplantation. PMID:26509214

Fluid inclusion and stable isotope (O, H, C, and S) constraints on the genesis of the Serrinha gold deposit, Gurupi Belt, northern Brazil

NASA Astrophysics Data System (ADS)

Klein, Evandro L.; Harris, Chris; Renac, Christophe; Giret, André; Moura, Candido A. V.; Fuzikawa, Kazuo

2006-05-01

The Serrinha gold deposit of the Gurupi Belt, northern Brazil, belongs to the class of orogenic gold deposits. The deposit is hosted in highly strained graphitic schist belonging to a Paleoproterozoic (˜2,160 Ma) metavolcano-sedimentary sequence. The ore-zones are up to 11 m thick, parallel to the regional NW-SE schistosity, and characterized by quartz-carbonate-sulfide veinlets and minor disseminations. Textural and structural data indicate that mineralization was syn- to late-tectonic and postmetamorphic. Fluid inclusion studies identified early CO2 (CH4-N2) and CO2 (CH4-N2)-H2O-NaCl inclusions that show highly variable phase ratios, CO2 homogenization, and total homogenization temperatures both to liquid and vapor, interpreted as the product of fluid immiscibility under fluctuating pressure conditions, more or less associated with postentrapment modifications. The ore-bearing fluid typically has 18-33mol% of CO2, up to 4mol% of N2, and less than 2mol% of CH4 and displays moderate to high densities with salinity around 4.5wt% NaCl equiv. Mineralization occurred around 310 to 335°C and 1.3 to 3.0 kbar, based on fluid inclusion homogenization temperatures and oxygen isotope thermometry with estimated oxygen fugacity indicating relatively reduced conditions. Stable isotope data on quartz, carbonate, and fluid inclusions suggest that veins formed from fluids with δ18OH2O and δDH2O (310-335°C) values of +6.2 to +8.4‰ and -19 to -80‰, respectively, which might be metamorphic and/or magmatic and/or mantle-derived. The carbon isotope composition (δ13C) varies from -14.2 to -15.7‰ in carbonates; it is -17.6‰ in fluid inclusion CO2 and -23.6‰ in graphite from the host rock. The δ34S values of pyrite are -2.6 to -7.9‰. The strongly to moderately negative carbon isotope composition of the carbonates and inclusion fluid CO2 reflects variable contribution of organic carbon to an originally heavier fluid (magmatic, metamorphic, or mantle-derived) at the site of deposition and sulfur isotopes indicate some oxidation of the originally reduced fluid. The deposition of gold is interpreted to have occurred mainly in response to phase separation and fluid-rock interactions such as CO2 removal and desulfidation reactions that provoked variations in the fluid pH and redox conditions.

Construction and Characterization of a Chitosan-Immobilized-Enzyme and β-Cyclodextrin-Included-Ferrocene-Based Electrochemical Biosensor for H₂O₂ Detection.

PubMed

Dong, Wenbo; Wang, Kaiyin; Chen, Yu; Li, Weiping; Ye, Yanchun; Jin, Shaohua

2017-07-28

An electrochemical detection biosensor was prepared with the chitosan-immobilized-enzyme (CTS-CAT) and β-cyclodextrin-included-ferrocene (β-CD-FE) complex for the determination of H₂O₂. Ferrocene (FE) was included in β-cyclodextrin (β-CD) to increase its stability. The structure of the β-CD-FE was characterized. The inclusion amount, inclusion rate, and electrochemical properties of inclusion complexes were determined to optimize the reaction conditions for the inclusion. CTS-CAT was prepared by a step-by-step immobilization method, which overcame the disadvantages of the conventional preparation methods. The immobilization conditions were optimized to obtain the desired enzyme activity. CTS-CAT/β-CD-FE composite electrodes were prepared by compositing the CTS-CAT with the β-CD-FE complex on a glassy carbon electrode and used for the electrochemical detection of H₂O₂. It was found that the CTS-CAT could produce a strong reduction peak current in response to H₂O₂ and the β-CD-FE could amplify the current signal. The peak current exhibited a linear relationship with the H₂O₂ concentration in the range of 1.0 × 10 -7 -6.0 × 10 -3 mol/L. Our work provided a novel method for the construction of electrochemical biosensors with a fast response, good stability, high sensitivity, and a wide linear response range based on the composite of chitosan and cyclodextrin.

From Access to Success: An Integrated Approach to Quality Higher Education Informed by Social Inclusion Theory and Practice

ERIC Educational Resources Information Center

Gidley, Jennifer M.; Hampson, Gary P.; Wheeler, Leone; Bereded-Samuel, Elleni

2010-01-01

Equitable access, success and quality in higher education are examined from a variety of ideological perspectives. "Quality" is positioned as a complex generic concept while "access" and "success" are identified as key concepts in the social inclusion domain, supplemented by the concept of "participation."…

Do Students See Themselves in the Music Curriculum? A Project to Encourage Inclusion

ERIC Educational Resources Information Center

Peters, Gretchen

2016-01-01

Greater diversity and inclusivity in music curricula are goals that permeate discussions in education. Achieving these goals, however, is complex and presents inherent difficulties as music not only values tradition but also promotes the past. Many music traditions were exclusionary and unintentionally cultivated a culture in which many people…

An Education Millennium Development Goal for Quality: Complexity and Democracy

ERIC Educational Resources Information Center

Barrett, Angeline M.

2011-01-01

A good quality education is inclusive, relevant and democratic. Of these three characteristics, the author contends that democratic is the most fundamental and underpins the other two. Education can only truly be inclusive and relevant if its goals are continuously the subject of open democratic debate, since education is a value-based,…

Platinated DNA oligonucleotides: new probes forming ultrastable conjugates with graphene oxide

NASA Astrophysics Data System (ADS)

Wang, Feng; Liu, Juewen

2014-05-01

Metal containing polymers have expanded the property of polymers by involving covalently associated metal complexes. DNA is a special block copolymer. While metal ions are known to influence DNA, little is explored on its polymer property when strong metal complexes are associated. In this work, we study cisplatin modified DNA as a new polymer and probe. Out of the complexes formed between cisplatin-A15, HAuCl4-A15, Hg2+-T15 and Ag+-C15, only the cisplatin adduct is stable under the denaturing gel electrophoresis condition. Each Pt-nucleobase bond gives a positive charge and thus makes DNA a zwitterionic polymer. This allows ultrafast adsorption of DNA by graphene oxide (GO) and the adsorbed complex is highly stable. Non-specific DNA, protein, surfactants and thiolated compounds cannot displace platinated DNA from GO, while non-modified DNA is easily displaced in most cases. The stable GO/DNA conjugate is further tested for surface hybridization. This is the first demonstration of using metallated DNA as a polymeric material for interfacing with nanoscale materials.Metal containing polymers have expanded the property of polymers by involving covalently associated metal complexes. DNA is a special block copolymer. While metal ions are known to influence DNA, little is explored on its polymer property when strong metal complexes are associated. In this work, we study cisplatin modified DNA as a new polymer and probe. Out of the complexes formed between cisplatin-A15, HAuCl4-A15, Hg2+-T15 and Ag+-C15, only the cisplatin adduct is stable under the denaturing gel electrophoresis condition. Each Pt-nucleobase bond gives a positive charge and thus makes DNA a zwitterionic polymer. This allows ultrafast adsorption of DNA by graphene oxide (GO) and the adsorbed complex is highly stable. Non-specific DNA, protein, surfactants and thiolated compounds cannot displace platinated DNA from GO, while non-modified DNA is easily displaced in most cases. The stable GO/DNA conjugate is further tested for surface hybridization. This is the first demonstration of using metallated DNA as a polymeric material for interfacing with nanoscale materials. Electronic supplementary information (ESI) available: Methods, additional gels, kinetics, mass spectrum. See DOI: 10.1039/c4nr00867g

Development and Optimization of Dispersible Tablet of Bacopa monnieri with Improved Functionality for Memory Enhancement

PubMed Central

Thakkar, Vaishali Tejas; Deshmukh, Amol; Hingorani, Lal; Juneja, Payal; Baldaniya, Lalji; Patel, Asha; Pandya, Tosha; Gohel, Mukesh

2017-01-01

Introduction: The Bacopa monnieri is traditional Ayurvedic medicine, and reported for memory-enhancing effects. The Bacoside is poorly soluble, bitter in taste and responsible for the memory enhancement action. Memory enhancer is commonly prescribed for children or elder people. Objective: Poor solubility, patient compliance and bitterness were a major driving force to develop taste masked β-cyclodextrin complex and dispersible tablets. Materials and Methods: The inclusion complex of Bacopa monnieri and β-cyclodextrin was prepared in different molar ratios of Bacopa monnieri by Co-precipitation method. Phase solubility study was conducted to evaluate the effect of β-cyclodextrin on aqueous solubility of Bacoside A. The characterization was determined by Fourier transformation infrared spectroscopy (FTIR),Differential scanning calorimetry (DSC) and X-ray diffraction study (XRD).Crospovidone and croscarmallose sodium were used as super disintigrant. The 32 full factorial design was adopted to investigate the influence of two superdisintegrants on the wetting time and disntegration time of the tablets. Conclusion: The result revels that molar ratio (1:4) of inclusion complex enhance 3-fold solubility. Full factorial design was successfully employed for the optimization of dispersible tablet of B. monnieri. The short-term accelerated stability study confirmed that high stability of B. monnieri in inclusion complex. PMID:28979076

Surface effects and desorption of tetracycline supramolecular complex on bovine dentine.

PubMed

Pataro, A L; Franco, C F; Santos, V R; Cortés, M E; Sinisterra, R D

2003-03-01

The aim of this in vitro study was to evaluate the antimicrobial activity, the substantivity, and surface effects of the inclusion compound tetracycline: beta-cyclodextrin on bovine roots. The antimicrobial activity was assessed by dentine slabs which had been immersed in the inclusion complex in concentrations 8.0%, 4.0%, 2.0%, 1.0%, 0.5% and 0.25% for 5min compared to a control of tetracycline hydrochloride. Each slab was tested in a broth of overnight culture of Actinobacillus actinomycetemcomitans (Y4-FDC). The inclusion complex significantly inhibited the A. actinomycetemcomitans (p<0.01) verified at concentrations from 1.0% to 8.0%. The substantivity of tetracycline was evaluated by the measure of desorption from the slabs previously immersed in solution samples and removed at 24h intervals. The tetracycline encapsulated in beta-cyclodextrin showed a flow rate near to zero order in comparison to free tetracycline. The surface morphology determined by SEM showed a more homogeneous and integrated layer with the complex compared to the effect of free tetracycline. We concluded that the root surfaces treated with tetracycline: beta-cyclodextrin release lower concentrations of active drug over 5 days at inhibitory concentrations against A. actinomycetemcomitans with enhanced disponibility in comparison to tetracycline.

Preparation and Physicochemical Characterization of an Inclusion Complex Between Dimethylated β-Cyclodextrin and a Drug Lead From a New Class of Orally Active Antimalarial 3,5-Diaryl-2-Aminopyridines.

PubMed

Joseph, Laurelle M; Chibale, Kelly; Caira, Mino R

2016-11-01

Cyclodextrins (CDs) were used to increase the aqueous solubility of a recently discovered orally active 3,5-diaryl-2-aminopyridine antimalarial drug lead (MMP). Phase-solubility studies using β-CD, hydroxypropyl-β-CD, and heptakis(2,6-di-O-methyl)-β-CD (DIMEB) as potential solubilizers for MMP yielded solubility enhancement factors of 17, 49, and 65, respectively, at 25°C with CD concentrations ∼20 mM. A crystalline complex, DIMEB⋅MMP⋅2H 2 O, was prepared and characterized by thermal and single-crystal X-ray analyses. The latter technique revealed preferential encapsulation of the hydrophobic methylsulfonylphenyl moiety of MMP within the CD cavity and protrusion of the more polar methoxypyridinyl and aminopyridine residues from the cavity. This inclusion mode results in a DIMEB complex with a new packing arrangement and an intricate network of intermolecular hydrogen bonds linking guest residues that protrude from 2 1 -related host cavities. A summary of the results of the performance of the inclusion complex in preliminary pharmacokinetic and efficacy tests in mouse models is provided. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Stalagmite geochemistry and the timing of the last interglacial-glacial transition in Central Europe (NE Hungary)

NASA Astrophysics Data System (ADS)

Siklosy, Z.; Demeny, A.; Pilet, S.; Leel-Ossy, Sz.; Lin, K.; Shen, C.-C.

2009-04-01

Speleothems can provide accurate chronologies for reconstructions of climate change by combination of U/Th dating and climate-related geochemical compositions. Geochemical studies of speleothems from Central Europe are mostly based on stable C and O isotope analyses, thus, complex geochemical studies combining isotope and trace element measurements are needed for more reliable climate models for this transitional area between oceanic and continental regions. We present stable H-C-O isotope and trace element records obtained on speleothems covering the Last Interglacial (MIS 5e) and the transition to MIS 5d. A stalagmite from Baradla Cave grew from 127.5 to 110 ka. Accelerated growth rates have been detected by U/Th age data in the 127 to 126 ka and 119 to 117 ka parts. Trace element compositions and 230Th/232Th ratios suggest changes in the hydrological regime, whereby early calcite precipitates formed in fissures during the dry and cold glacial period were dissolved by the starting flux of infiltrating meteoric water (producing elevated dissolved ion concentration but low detrital Th component), then the increasing amount of dripwater during the interglacial period resulted in trace element dilution. Temperature and precipitation amount variations are also reflected by the stable isotope compositions. Oxygen isotope composition shows a continuous increase from 127.5 ka until about 118 ka most probably related to temperature rise, whereas C isotope values are shifted in negative direction suggesting increasing humidity in accordance with trace element contents. The presumably warmest period at ca. 118 ka is associated with rather arid climate as indicated by peak d18O values coinciding with the highest dD values of fluid inclusion water. This is followed by a pronounced negative shift in both O and H isotope values, similarly to recent Alpine studies (Meyer et al., 2008), most probably related to cooling. Hydrogen isotope compositions of fluid inclusion water evaluated together with calculated oxygen isotope compositions of water indicate warming and increasing significance of summer precipitation at the latest period of the last interglacial, then increasing importance of winter precipitation and/or changes in oceanic source composition during the cooling phase. The good agreement with other (Alpine and marine) records indicate a synchronous climate change. However, after a negative shift in the wet/warm phase (increasing soil activity), C isotope values start to increase already at about 119 ky BP, warning to the use of the two isotope systems as event correlation tools. In conclusion, our combined isotope and trace element study indicate a complex pattern of temperature and humidity variations during and right after the Last Interglacial. Acknowledgements — This study was financially supported by the Hungarian Scientific Research Fund (OTKA T 049713). Measurements of U-Th isotopic compositions and and 230Th dates were supported by the National Science Council grants (94-2116-M002-012, 97-2752-M002-004-PAE & -005-PAE to C.C.S.). [Meyer, M.; Spötl, C.; Mangini, A. (2008): The demise of the Last Interglacial recorded in isotopically dated speleothems from the Alps. Quaternary Science Reviews, 27, 476-496.

A stable partitioned FSI algorithm for rigid bodies and incompressible flow. Part II: General formulation

NASA Astrophysics Data System (ADS)

Banks, J. W.; Henshaw, W. D.; Schwendeman, D. W.; Tang, Qi

2017-08-01

A stable partitioned algorithm is developed for fluid-structure interaction (FSI) problems involving viscous incompressible flow and rigid bodies. This added-mass partitioned (AMP) algorithm remains stable, without sub-iterations, for light and even zero mass rigid bodies when added-mass and viscous added-damping effects are large. The scheme is based on a generalized Robin interface condition for the fluid pressure that includes terms involving the linear acceleration and angular acceleration of the rigid body. Added mass effects are handled in the Robin condition by inclusion of a boundary integral term that depends on the pressure. Added-damping effects due to the viscous shear forces on the body are treated by inclusion of added-damping tensors that are derived through a linearization of the integrals defining the force and torque. Added-damping effects may be important at low Reynolds number, or, for example, in the case of a rotating cylinder or rotating sphere when the rotational moments of inertia are small. In this second part of a two-part series, the general formulation of the AMP scheme is presented including the form of the AMP interface conditions and added-damping tensors for general geometries. A fully second-order accurate implementation of the AMP scheme is developed in two dimensions based on a fractional-step method for the incompressible Navier-Stokes equations using finite difference methods and overlapping grids to handle the moving geometry. The numerical scheme is verified on a number of difficult benchmark problems.

Solving the Problem of Linear Viscoelasticity for Piecewise-Homogeneous Anisotropic Plates

NASA Astrophysics Data System (ADS)

Kaloerov, S. A.; Koshkin, A. A.

2017-11-01

An approximate method for solving the problem of linear viscoelasticity for thin anisotropic plates subject to transverse bending is proposed. The method of small parameter is used to reduce the problem to a sequence of boundary problems of applied theory of bending of plates solved using complex potentials. The general form of complex potentials in approximations and the boundary conditions for determining them are obtained. Problems for a plate with elliptic elastic inclusions are solved as an example. The numerical results for a plate with one, two elliptical (circular), and linear inclusions are analyzed.

Multiphase inclusions in plagioclase from anorthosites in the Stillwater Complex, Montana: implications for the origin of the anorthosites

USGS Publications Warehouse

Loferski, P.J.; Arculus, R.J.

1993-01-01

Multiphase inclusions, consisting of clinopyroxene+ilmenite+apatite, occur within cumulus plagioclase grains from anorthosites in the Stillwater Complex, Montana, and in other rocks from the Middle Banded series of the intrusion. The textures and constant modal mineralogy of the inclusions indicate that they were incorporated in the plagioclase as liquid droplets that later crystallized rather than as solid aggregates. Their unusual assemblage, including a distinctive manganiferous ilmenite and the presence of baddeleyite (ZrO2), indicates formation from an unusual liquid. A process involving silicater liquid immiscibility is proposed, whereby small globules of a liquid enriched in Mg, Fe, Ca, Ti, P, REE, Zr and Mn exsolved from the main liquid that gave rise to the anorthosites, became trapped in the plagioclase, and later crystallized to form the inclusions. The immiscibility could have occurred locally within compositional boundaries around crystallizing plagioclase grains or it could have occurred pervasively throughout the liquid. It is proposed that the two immiscible liquids were analogous, n terms of their melt structures, to immiscible liquid pairs reported in the literature both in experiments and in natural basalts. For the previously reported pairs, immiscibility is between a highly polymerized liquid, typically granitic in composition, and a depolymerized liquid, typically ferrobasaltic in composition. In the case of the anorthosites, the depolymerized liquid is represented by the inclusions, and the other liquid was a highly polymerized aluminosilicate melt with a high normative plagioclase content from which the bulk of the anorthosites crystallized. Crystallization of the anorthosites from this highly polymerized liquid accounts for various distinctive textural and chemical features of the anorthosites compared to other rocks in the Stillwater Complex. A lack of correlation between P contents and chondrite-normalized rare earth element (REE) ratios of plagioclase separates indicates that the amount of apatite in the inclusions is too low to affect the REE signature of the plagioclase separates. Nevertheless, workers should use caution when attempting REE modelling studies of cumulates having low REE contents, because apatite-bearing inclusions can potentially cause problems. ?? 1993 Springer-Verlag.

Competition of hydrogen bonds and halogen bonds in complexes of hypohalous acids with nitrogenated bases.

PubMed

Alkorta, Ibon; Blanco, Fernando; Solimannejad, Mohammad; Elguero, Jose

2008-10-30

A theoretical study of the complexes formed by hypohalous acids (HOX, X = F, Cl, Br, I, and At) with three nitrogenated bases (NH 3, N 2, and NCH) has been carried out by means of ab initio methods, up to MP2/aug-cc-pVTZ computational method. In general, two minima complexes are found, one with an OH...N hydrogen bond and the other one with a X...N halogen bond. While the first one is more stable for the smallest halogen derivatives, the two complexes present similar stabilities for the iodine case and the halogen-bonded structure is the most stable one for the hypoastatous acid complexes.

Molecular structures of the inclusion complexes beta-cyclodextrin-1,2-bis(4-aminophenyl)ethane and beta-cyclodextrin-4,4'-diaminobiphenyl; packing of dimeric beta-cyclodextrin inclusion complexes.

PubMed

Giastas, Petros; Yannakopoulou, Konstantina; Mavridis, Irene M

2003-04-01

The present investigation is part of an ongoing study on the influence of the long end-functonalized guest molecules DBA and BNZ in the crystal packing of beta-cyclodextrin (betaCD) dimeric complexes. The title compounds are 2:2 host:guest complexes showing limited host-guest hydrogen bonding at the primary faces of the betaCD dimers. Within the betaCD cavity the guests exhibit mutual pi...pi interactions and between betaCD dimers perpendicular NH...pi interactions. The DBA guest molecule exhibits one extended and two bent conformations in the complex. The BNZ guest molecule is not planar inside betaCD, in contrast to the structure of BNZ itself, which indicates that the cavity isolates the molecules and forbids the pi...pi stacking of the aromatic rings. NMR spectroscopy studies show that in aqueous solution both DBA and BNZ form strong complexes that have 1:1 stoichiometry and structures similar to the solid state ones. The relative packing of the dimers is the same in both complexes. The axes of two adjacent dimers form an angle close to 20 degrees and have a lateral displacement approximately 2.45 A, both of which characterize the screw-channel mode of packing. Although the betaCD/BNZ complex indeed crystallizes in a space group characterizing the latter mode, the betaCD/DBA complex crystallizes in a space group with novel dimensions not resembling any of the packing modes reported so far. The new lattice is attributed to the three conformations exhibited by the guest in the crystals. However, this lattice can be transformed into another, which is isostructural to that of the betaCD/BNZ inclusion complex, if the conformation of the guest is not taken into account.

Electrically active induced energy levels and metastability of B and N vacancy-complexes in 4H–SiC

NASA Astrophysics Data System (ADS)

Igumbor, E.; Olaniyan, O.; Mapasha, R. E.; Danga, H. T.; Omotoso, E.; Meyer, W. E.

2018-05-01

Electrically active induced energy levels in semiconductor devices could be beneficial to the discovery of an enhanced p or n-type semiconductor. Nitrogen (N) implanted into 4H–SiC is a high energy process that produced high defect concentrations which could be removed during dopant activation annealing. On the other hand, boron (B) substituted for silicon in SiC causes a reduction in the number of defects. This scenario leads to a decrease in the dielectric properties and induced deep donor and shallow acceptor levels. Complexes formed by the N, such as the nitrogen-vacancy centre, have been reported to play a significant role in the application of quantum bits. In this paper, results of charge states thermodynamic transition level of the N and B vacancy-complexes in 4H–SiC are presented. We explore complexes where substitutional N/N or B/B sits near a Si (V) or C (V) vacancy to form vacancy-complexes (NV, NV, NV, NV, BV, BV, BV and BV). The energies of formation of the N related vacancy-complexes showed the NV to be energetically stable close to the valence band maximum in its double positive charge state. The NV is more energetically stable in the double negative charge state close to the conduction band minimum. The NV on the other hand, induced double donor level and the NV induced a double acceptor level. For B related complexes, the BV and BV were energetically stable in their single positive charge state close to the valence band maximum. As the Fermi energy is varied across the band gap, the neutral and single negative charge states of the BV become more stable at different energy levels. B and N related complexes exhibited charge state controlled metastability behaviour.

Factors Associated with Primary School Teachers' Attitudes Towards the Inclusion of Students with Disabilities.

PubMed

Vaz, Sharmila; Wilson, Nathan; Falkmer, Marita; Sim, Angela; Scott, Melissa; Cordier, Reinie; Falkmer, Torbjörn

2015-01-01

Teachers' attitudes toward inclusion are often based on the practical implementation of inclusive education rather than a specific ideology and understanding of inclusiveness. This study aimed to identify the factors associated with primary school teachers' attitudes towards inclusion of students with all disabilities in regular schools. Seventy four primary school teachers participated in a cross-sectional survey conducted in Western Australia. Teachers' attitudes and efficacy toward integration of students with disabilities were measured using the Opinions Relative to Integration of Students with Disabilities scale and Bandura's Teacher Efficacy scale respectively. Four teacher attributes-age, gender, teaching self-efficacy and training collectively explained 42% of the variability in teachers' attitude toward including students with disabilities. The current study further contributes to the accumulation of knowledge that can unpack the complex pattern of factors that should be considered to promote positive attitudes towards inclusive schools.

Factors Associated with Primary School Teachers’ Attitudes Towards the Inclusion of Students with Disabilities

PubMed Central

Vaz, Sharmila; Wilson, Nathan; Falkmer, Marita; Sim, Angela; Scott, Melissa; Cordier, Reinie; Falkmer, Torbjörn

2015-01-01

Objective Teachers' attitudes toward inclusion are often based on the practical implementation of inclusive education rather than a specific ideology and understanding of inclusiveness. This study aimed to identify the factors associated with primary school teachers' attitudes towards inclusion of students with all disabilities in regular schools. Method Seventy four primary school teachers participated in a cross-sectional survey conducted in Western Australia. Teachers' attitudes and efficacy toward integration of students with disabilities were measured using the Opinions Relative to Integration of Students with Disabilities scale and Bandura's Teacher Efficacy scale respectively. Results Four teacher attributes—age, gender, teaching self-efficacy and training collectively explained 42% of the variability in teachers' attitude toward including students with disabilities. Conclusion The current study further contributes to the accumulation of knowledge that can unpack the complex pattern of factors that should be considered to promote positive attitudes towards inclusive schools. PMID:26317862

First findings of monocrystalline aragonite inclusions in garnet from diamond-grade UHPM rocks (Kokchetav Massif, Northern Kazakhstan).

PubMed

Korsakov, Andrey V; Vandenabeele, Peter; Perraki, Maria; Moens, Luc

2011-10-01

The presence of aragonite inclusions in garnet from diamond-grade metamorphic rocks from the Kokchetav Massif, Northern Kazakhstan was identified for the first time by means of Raman analyses and mapping. Aragonite appears within the inclusions up to 50 μm in size as a single crystal. These inclusions have rounded shape. The grain boundary between the host-garnet is smooth. No cracks occur around the aragonite inclusions. No significant shift in the main aragonite Raman band was measured. These observations indicate that residual pressure within the inclusion is minor. These findings imply either non-UHPM origin of the host garnet or significant plastic deformation of host minerals during retrograde stage. These features should be taken into account for recovery peak metamorphic conditions and modeling of exhumation processes of UHPM complexes. Copyright © 2010 Elsevier B.V. All rights reserved.

Effects of Surface-Modified MgO Nanoparticles on Inclusion Characteristics and Microstructure in Carbon Structural Steel

NASA Astrophysics Data System (ADS)

Guo, Hao; Yang, Shufeng; Li, Jingshe; Zhao, Mengjing; Chen, Zhengyang; Zhang, Xueliang; Li, Jikang

2018-05-01

An innovative approach involving chemical modification of the surface of MgO nanoparticles (NPs) for steelmaking and application of NPs to carbon structural steel has been investigated. The results show that the inclusions in the test steels were completely converted to MgAl2O4 spinel or MnS complex inclusions. The mean inclusion size decreased with increasing NP content from 0.01% to 0.03%, but increased at 0.05% because of NP aggregation. Addition of NPs increased the amount of intragranular ferrite and prevented polygonal ferrite formation, thereby enhancing the impact toughness. Impact tests showed that the dimple fractures in steel with 0.05% NP content were deeper than those in the other samples because the MgAl2O4 inclusions were larger. The surface-modified MgO NPs had a major effect on the inclusion characteristics and microstructure of carbon structural steel.

This new field of inclusive education: beginning a dialogue on conceptual foundations.

PubMed

Danforth, Scot; Naraian, Srikala

2015-02-01

Numerous scholars have suggested that the standard knowledge base of the field of special education is not a suitable intellectual foundation for the development of research, policy, and practice in the field of inclusive education. Still, we have yet to have a dialogue on what conceptual foundations may be most generative for the growth and development of the field of inclusive education. This article imagines and initiates such a new dialogue among educational researchers and teacher educators about the intellectual resources that can best support inclusive educators everywhere. As inclusive education gets increasingly taken up within international policy discourses, it may be imperative to explore and identify theories and ideas that can be responsive to diverse and hugely unequal contexts of schooling. This article forwards an initial collection of intellectual resources for an inclusive education that can accommodate such complex schooling conditions and invites rich scholarly exchange on this issue.

Ultrastructural features of the osteoclasts from Paget's disease of bone in relation to a viral aetiology.

PubMed Central

Harvey, L; Gray, T; Beneton, M N; Douglas, D L; Kanis, J A; Russell, R G

1982-01-01

The ultrastructure of the osteocytes, osteoblasts, osteoclasts, haemopoietic and other connective tissue cells was examined in 27 biopsies from 22 patients with Paget's disease of bone. Electron microscopy showed characteristic nuclear and cytoplasmic inclusions in the osteoclasts of all of the 25 biopsies exhibiting histological evidence of Paget's disease. Such inclusions were absent from all the other types examined. The intranuclear inclusions consisted of stacked rows or complex whorls of tubular filaments with an individual filament diameter of 12-15 nm, often arranged in a paracrystalline array. The frequency of occurrence of inclusions in the osteoclasts and their individual nuclei measured quantitatively in 18 of the biopsies was related to the histological severity of the disease process. The similarity of the observed inclusions to those of paramyxovirus inclusion bodies (particularly measles) support the hypothesis that Paget's disease is a slow virus infection. Images PMID:7096600

Three-dimensional imaging of crystalline inclusions embedded in intact maize stalks.

PubMed

Badger, John; Lal, Jyotsana; Harder, Ross; Inouye, Hideyo; Gleber, S Charlotte; Vogt, Stefan; Robinson, Ian; Makowski, Lee

2013-10-03

Mineral inclusions in biomass are attracting increased scrutiny due to their potential impact on processing methods designed to provide renewable feedstocks for the production of chemicals and fuels. These inclusions are often sculpted by the plant into shapes required to support functional roles that include the storage of specific elements, strengthening of the plant structure, and providing a defense against pathogens and herbivores. In situ characterization of these inclusions faces substantial challenges since they are embedded in an opaque, complex polymeric matrix. Here we describe the use of Bragg coherent diffraction imaging (BCDI) to study mineral inclusions within intact maize stalks. Three-dimensional BCDI data sets were collected and used to reconstruct images of mineral inclusions at 50-100 nm resolution. Asymmetries in the intensity distributions around the Bragg peaks provided detailed information about the deformation fields within these crystal particles revealing lattice defects that result in distinct internal crystal domains.

Exploring the Molecular Design of Protein Interaction Sites with Molecular Dynamics Simulations and Free Energy Calculations†

PubMed Central

Liang, Shide; Li, Liwei; Hsu, Wei-Lun; Pilcher, Meaghan N.; Uversky, Vladimir; Zhou, Yaoqi; Dunker, A. Keith; Meroueh, Samy O.

2009-01-01

The significant work that has been invested toward understanding protein–protein interaction has not translated into significant advances in structure-based predictions. In particular redesigning protein surfaces to bind to unrelated receptors remains a challenge, partly due to receptor flexibility, which is often neglected in these efforts. In this work, we computationally graft the binding epitope of various small proteins obtained from the RCSB database to bind to barnase, lysozyme, and trypsin using a previously derived and validated algorithm. In an effort to probe the protein complexes in a realistic environment, all native and designer complexes were subjected to a total of nearly 400 ns of explicit-solvent molecular dynamics (MD) simulation. The MD data led to an unexpected observation: some of the designer complexes were highly unstable and decomposed during the trajectories. In contrast, the native and a number of designer complexes remained consistently stable. The unstable conformers provided us with a unique opportunity to define the structural and energetic factors that lead to unproductive protein–protein complexes. To that end we used free energy calculations following the MM-PBSA approach to determine the role of nonpolar effects, electrostatics and entropy in binding. Remarkably, we found that a majority of unstable complexes exhibited more favorable electrostatics than native or stable designer complexes, suggesting that favorable electrostatic interactions are not prerequisite for complex formation between proteins. However, nonpolar effects remained consistently more favorable in native and stable designer complexes reinforcing the importance of hydrophobic effects in protein–protein binding. While entropy systematically opposed binding in all cases, there was no observed trend in the entropy difference between native and designer complexes. A series of alanine scanning mutations of hot-spot residues at the interface of native and designer complexes showed less than optimal contacts of hot-spot residues with their surroundings in the unstable conformers, resulting in more favorable entropy for these complexes. Finally, disorder predictions revealed that secondary structures at the interface of unstable complexes exhibited greater disorder than the stable complexes. PMID:19113835

Biopolymer-reinforced synthetic granular nanocomposites for affordable point-of-use water purification.

PubMed

Sankar, Mohan Udhaya; Aigal, Sahaja; Maliyekkal, Shihabudheen M; Chaudhary, Amrita; Anshup; Kumar, Avula Anil; Chaudhari, Kamalesh; Pradeep, Thalappil

2013-05-21

Creation of affordable materials for constant release of silver ions in water is one of the most promising ways to provide microbially safe drinking water for all. Combining the capacity of diverse nanocomposites to scavenge toxic species such as arsenic, lead, and other contaminants along with the above capability can result in affordable, all-inclusive drinking water purifiers that can function without electricity. The critical problem in achieving this is the synthesis of stable materials that can release silver ions continuously in the presence of complex species usually present in drinking water that deposit and cause scaling on nanomaterial surfaces. Here we show that such constant release materials can be synthesized in a simple and effective fashion in water itself without the use of electrical power. The nanocomposite exhibits river sand-like properties, such as higher shear strength in loose and wet forms. These materials have been used to develop an affordable water purifier to deliver clean drinking water at US $2.5/y per family. The ability to prepare nanostructured compositions at near ambient temperature has wide relevance for adsorption-based water purification.

Biopolymer-reinforced synthetic granular nanocomposites for affordable point-of-use water purification

PubMed Central

Sankar, Mohan Udhaya; Aigal, Sahaja; Maliyekkal, Shihabudheen M.; Chaudhary, Amrita; Anshup; Kumar, Avula Anil; Chaudhari, Kamalesh; Pradeep, Thalappil

2013-01-01

Creation of affordable materials for constant release of silver ions in water is one of the most promising ways to provide microbially safe drinking water for all. Combining the capacity of diverse nanocomposites to scavenge toxic species such as arsenic, lead, and other contaminants along with the above capability can result in affordable, all-inclusive drinking water purifiers that can function without electricity. The critical problem in achieving this is the synthesis of stable materials that can release silver ions continuously in the presence of complex species usually present in drinking water that deposit and cause scaling on nanomaterial surfaces. Here we show that such constant release materials can be synthesized in a simple and effective fashion in water itself without the use of electrical power. The nanocomposite exhibits river sand-like properties, such as higher shear strength in loose and wet forms. These materials have been used to develop an affordable water purifier to deliver clean drinking water at US $2.5/y per family. The ability to prepare nanostructured compositions at near ambient temperature has wide relevance for adsorption-based water purification. PMID:23650396

Cooperative Binding of Cyclodextrin Dimers to Isoflavone Analogues Elucidated by Free Energy Calculations.

PubMed

Zhang, Haiyang; Tan, Tianwei; Hetényi, Csaba; Lv, Yongqin; van der Spoel, David

2014-04-03

Dimerization of cyclodextrin (CD) molecules is an elementary step in the construction of CD-based nanostructured materials. Cooperative binding of CD cavities to guest molecules facilitates the dimerization process and, consequently, the overall stability and assembly of CD nanostructures. In the present study, all three dimerization modes (head-to-head, head-to-tail, and tail-to-tail) of β-CD molecules and their binding to three isoflavone drug analogues (puerarin, daidzin, and daidzein) were investigated in explicit water surrounding using molecular dynamics simulations. Total and individual contributions from the binding partners and solvent environment to the thermodynamics of these binding reactions are quantified in detail using free energy calculations. Cooperative drug binding to two CD cavities gives an enhanced binding strength for daidzin and daidzein, whereas for puerarin no obvious enhancement is observed. Head-to-head dimerization yields the most stable complexes for inclusion of the tested isoflavones (templates) and may be a promising building block for construction of template-stabilized CD nanostructures. Compared to the case of CD monomers, the desolvation of CD dimers and entropy changes upon complexation prove to be influential factors of cooperative binding. Our results shed light on key points of the design of CD-based supramolecular assemblies. We also show that structure-based calculation of binding thermodynamics can quantify stabilization caused by cooperative effects in building blocks of nanostructured materials.

New formulation of an old drug in hypertension treatment: the sustained release of captopril from cyclodextrin nanoparticles

PubMed Central

de Azevedo, Mariangela de Burgos M; Tasic, Ljubica; Fattori, Juliana; Rodrigues, Fábio HS; Cantos, Fabiana C; Ribeiro, Leandro P; de Paula, Vanice; Ianzer, Danielle; Santos, Robson AS

2011-01-01

Captopril (CAP) was the first angiotensin I-converting enzyme (ACE) inhibitor to be developed and is widely used in hypertension treatment. On the other hand, cyclodextrins (CDs) are cyclic oligosaccharides whose cone-shaped cavity allows formation of noncovalent inclusion complexes with appropriately sized guest molecules, thus modifying guest physical, chemical, and biological properties. Herein, the physicochemical characterization and in vivo ACE inhibition evaluation of seven CAP/CD complexes are reported. The inclusion complexes were prepared by spray-drying, freeze-drying, kneading, or lyophilization methods and characterized by nuclear magnetic resonance, Fourier-transformed infrared spectroscopy, X-ray diffraction, differential scanning calorimetry, and scanning electron microscopy techniques. In vivo assays compared CAP and CAP/CD complex administration (0.5 mg kg−1 or 0.09 mg kg−1, n = 4–7) to evaluate the ACE inhibition by continuous infusion of angiotensin I (30 ng 50 μL−1 min−1) in conscious Wistar rats. The physicochemical analysis demonstrated complete amorphization and complexation between CAP and CDs, indicating the substitution of water molecules inside the CD cavity with CAP. During the infusion of angiotensin I, the administration of all CAP/CD complexes induced a reduction in mean arterial pressure similar to that observed upon CAP administration. The nanoparticles obtained by the kneading method (CAP/α-CD:KM) showed a potent and long-lasting inhibitory activity (∼22 hours) on the angiotensin I pressor effect. The results suggest that the inclusion complex of CAP and α-CD can function as a novel antihypertensive formulation that may improve therapeutic use of CAP by reducing its oral dose administration to once per day, thus providing better quality of life for almost 25% of the world’s population who suffer from hypertension. PMID:21720512

The partitioning of Fe, Ni, Cu, Pt, and Au between sulfide, metal, and fluid phases: A pilot study

NASA Astrophysics Data System (ADS)

Ballhaus, C.; Ryan, C. G.; Mernagh, T. P.; Green, D. H.

1994-01-01

This paper describes new experimental and analytical techniques to study element partitioning behavior between crystalline material and a late- to post-magmatic fluid phase. Samples of the fluid phase are isolated at experimental run conditions as synthetic fluid in quartz. Individual fluid inclusions are later analyzed for dissolved metals using Proton Induced X-ray Emission (PIXE). Back reactions between fluid and solid phases during quenching are prevented because the fluid is isolated at the experimental pressure, temperature ( P, T) conditions before quenching occurs. The technique is applied to study the partitioning of chalcophile elements (Fe, Ni, Cu, Pt and Au) between sulfide phases, metal alloys and supercritical SiO 2-NaCl-saturated H2O ± CH4- CO2- H2S fluids. Synthetic Ni-Cu-rich monosulfide solid solution (mss) doped with PtS or Au is packed in a quartz capsule and, together with a hydrogen buffer capsule and compounds to generate a fluid phase, welded shut in an outer Pt or Au metal capsule. The fluid phase is generated by combustion and reaction of various C-H-O fluid components during heating. Depending on capsule material and sample composition, the run products consist of platiniferous or auriferous mss, Pt-Fe, or ( Au, Cu) alloy phases, PtS, Fe 3O 4, sometimes a Cu-rich sulfide melt, and a fluid phase. Samples of the fluid are trapped in the walls of the quartz sample capsule as polyphase fluid inclusions. All phases are now available for analysis: fluid speciation is analyzed by piercing the outer metal capsule under vacuum and feeding the released fluid into a mass spectrometer. Phases and components within fluid inclusions are identified with Raman spectroscopy. Platinum and gold in solid solution in mss are determined with a CAMECA SX50 electron microanalyser. Metal contents trapped in selected fluid inclusions are determined quantitatively by in situ analysis with a proton microprobe using PIXE and a correction procedure specifically developed for quantitative fluid inclusion analysis. Initial results of metal solubilities in the fluid are as follows. Iron decreases from above 6,000 ppm under reduced conditions in the presence of H 2S in the fluid, to less than 1,000 ppm if hematite is stable in the crystalline run product. Copper and gold concentrations in the fluid range from about 600 to over 1200 and from 150 to about 270 ppm, respectively. The solubilities of these two metals in NaCl-saturated fluids are apparently independent of fluid speciations covered here. Nickel is mostly below detection limit (<10 ppm) and apparently poorly soluble in high-temperature fluid phases. Platinum concentrations in fluid inclusions are highly variable even among fluid inclusions of single runs, possibly because Pt tends to form multi-atom complexes in fluid phases.

12. VIEW OF THE SOUTHWEST ELEVATION OF THE STABLES. THE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. VIEW OF THE SOUTHWEST ELEVATION OF THE STABLES. THE STABLES ARE LOCATED AT THE EXTREME SOUTHWESTERN END OF THE MINE COMPLEX. - Tower Hill No. 2 Mine, Approximately 0.47 mile Southwest of intersection of Stone Church Road & Township Route 561, Hibbs, Fayette County, PA

The α-cyclodextrin complex of the Moringa isothiocyanate suppresses lipopolysaccharide-induced inflammation in RAW 264.7 macrophage cells through Akt and p38 inhibition.

PubMed

Giacoppo, Sabrina; Rajan, Thangavelu Soundara; Iori, Renato; Rollin, Patrick; Bramanti, Placido; Mazzon, Emanuela

2017-06-01

In the last decades, a growing need to discover new compounds for the prevention and treatment of inflammatory diseases has led researchers to consider drugs derived from natural products as a valid option in the treatment of inflammation-associated disorders. The purpose of the present study was to investigate the anti-inflammatory effects of a new formulation of Moringa oleifera-derived 4-(α-L-rhamnopyranosyloxy)benzyl isothiocyanate as a complex with alpha-cyclodextrin (moringin + α-CD) on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells, a common model used for inflammation studies. In buffered/aqueous solution, the moringin + α-CD complex has enhanced the water solubility and stability of this isothiocyanate by forming a stable inclusion system. Our results showed that moringin + α-CD inhibits the production of inflammatory mediators in LPS-stimulated macrophages by down-regulation of pro-inflammatory cytokines (TNF-α and IL-1β), by preventing IκB-α phosphorylation, translocation of the nuclear factor-κB (NF-κB), and also via the suppression of Akt and p38 phosphorylation. In addition, as a consequence of upstream inhibition of the inflammatory pathway following treatment with moringin + α-CD, the modulation of the oxidative stress (results focused on the expression of iNOS and nitrotyrosine) and apoptotic pathway (Bax and Bcl-2) was demonstrated. Therefore, moringin + α-CD appears to be a new relevant helpful tool to use in clinical practice for inflammation-associated disorders.

PA700, the regulatory complex of the 26S proteasome, interferes with alpha-synuclein assembly.

PubMed

Ghee, Medeva; Melki, Ronald; Michot, Nadine; Mallet, Jacques

2005-08-01

Parkinson's disease is characterized by the loss of dopaminergic neurons in the nigrostriatal pathway accompanied by the presence of intracellular cytoplasmic inclusions, termed Lewy bodies. Fibrillized alpha-synuclein forms the major component of Lewy bodies. We reported a specific interaction between rat alpha-synuclein and tat binding protein 1, a subunit of PA700, the regulatory complex of the 26S proteasome. It has been demonstrated that PA700 prevents the aggregation of misfolded, nonubiquinated substrates. In this study, we examine the effect of PA700 on the aggregation of wild-type and A53T mutant alpha-synuclein. PA700 inhibits both wild-type and A53T alpha-synuclein fibril formation as measured by Thioflavin T fluorescence. Using size exclusion chromatography, we present evidence for a stable PA700-alpha-synuclein complex. Sedimentation analyses reveal that PA700 sequesters alpha-synuclein in an assembly incompetent form. Analysis of the morphology of wild-type and A53T alpha-synuclein aggregates during the course of fibrillization by electron microscopy demonstrate the formation of amyloid-like fibrils. Secondary structure analyses of wild-type and A53T alpha-synuclein assembled in the presence of PA700 revealed a decrease in the overall amount of assembled alpha-synuclein with no significant change in protein conformation. Thus, PA700 acts on alpha-synuclein assembly and not on the structure of fibrils. We hypothesize that PA700 sequesters alpha-synuclein oligomeric species that are the precursors of the fibrillar form of the protein, thus preventing its assembly into fibrils.

On the interconnection of stable protein complexes: inter-complex hubs and their conservation in Saccharomyces cerevisiae and Homo sapiens networks.

PubMed

Guerra, Concettina

2015-01-01

Protein complexes are key molecular entities that perform a variety of essential cellular functions. The connectivity of proteins within a complex has been widely investigated with both experimental and computational techniques. We developed a computational approach to identify and characterise proteins that play a role in interconnecting complexes. We computed a measure of inter-complex centrality, the crossroad index, based on disjoint paths connecting proteins in distinct complexes and identified inter-complex hubs as proteins with a high value of the crossroad index. We applied the approach to a set of stable complexes in Saccharomyces cerevisiae and in Homo sapiens. Just as done for hubs, we evaluated the topological and biological properties of inter-complex hubs addressing the following questions. Do inter-complex hubs tend to be evolutionary conserved? What is the relation between crossroad index and essentiality? We found a good correlation between inter-complex hubs and both evolutionary conservation and essentiality.

Effect of amylopectin on the rheological properties of aqueous dispersions of starch-sodium palmitate complexes

USDA-ARS?s Scientific Manuscript database

Aqueous dispersions of normal and high-amylose corn starch were steam jet cooked and blended with aqueous solutions of sodium palmitate to form amylose inclusion complexes. Partial conversion of complexed sodium palmitate to palmitic acid by addition of acetic acid led to the formation of gels. Bl...

Life in Inclusive Classrooms: Storytelling with Disability Studies in Education. Occasional Paper Series 36

ERIC Educational Resources Information Center

Valente, Joseph Michael, Ed.; Danforth, Scot, Ed.

2016-01-01

This issue of the Occasional Papers Series aims to draw attention to the use of storytelling as a medium for provoking dialogue about inclusive classrooms and school communities. It offers readers stories of classroom life that provide insights into understanding the complexities that make up the lives of children with disabilities, their…

Critical Reflection by Teacher Candidates on Cases Based in their Experience: Teacher Education for Inclusive Education

ERIC Educational Resources Information Center

Hutchinson, Nancy L.

2004-01-01

Recent changes in education, including inclusion of students with disabilities, promise to heighten the complexity of teaching. Preparing reflective teachers may help to deal with these increasing demands. This paper reports analysis of critical reflection and two other features in cases authored by teacher candidates and submitted in a course on…

Between Inclusion and Fairness: Social Justice Perspective to Participation in Adult Education

ERIC Educational Resources Information Center

Boyadjieva, Pepka; Ilieva-Trichkova, Petya

2017-01-01

The article claims that equity is an indispensable dimension of the widening of access to adult education. Building on the understanding of social justice in adult education as a complex phenomenon, two indicators are developed: an index of inclusion and an index of fairness in participation in adult education. The article analyses social justice…

Developing and Implementing Quality Inclusive Education in Hong Kong: Implications for Teacher Education

ERIC Educational Resources Information Center

Forlin, Chris

2010-01-01

The government in Hong Kong has mandated that all schools should start to accept children with special educational needs by employing a whole school approach. This is not a simple move for teachers as inclusive education is complex, involving a range of issues including developing appropriate government and school policy; providing relevant…

Hot-melt extrusion as a continuous manufacturing process to form ternary cyclodextrin inclusion complexes.

PubMed

Thiry, Justine; Krier, Fabrice; Ratwatte, Shenelka; Thomassin, Jean-Michel; Jerome, Christine; Evrard, Brigitte

2017-01-01

The aim of this study was to evaluate hot-melt extrusion (HME) as a continuous process to form cyclodextrin (CD) inclusion complexes in order to increase the solubility and dissolution rate of itraconazole (ITZ), a class II model drug molecule of the Biopharmaceutics Classification System. Different CD derivatives were tested in a 1:1 (CD:ITZ) molar ratio to obtain CD ternary inclusion complexes in the presence of a polymer, namely Soluplus ® (SOL). The CD used in this series of experiments were β-cyclodextrin (βCD), hydroxypropyl-β-cyclodextrin (HPβCD) with degrees of substitution of 0.63 and 0.87, randomly methylated β-cyclodextrin (Rameb ® ), sulfobutylether-β-cyclodextrin (Captisol ® ) and methyl-β-cyclodextrin (Crysmeb ® ). Rheology testing and mini extrusion using a conical twin screw mini extruder were performed to test the processability of the different CD mixtures since CD are not thermoplastic. This allowed Captisol ® and Crysmeb ® to be discarded from the study due to their high impact on the viscosity of the SOL/ITZ mixture. The remaining CD were processed by HME in an 18mm twin screw extruder. Saturation concentration measurements confirmed the enhancement of solubility of ITZ for the four CD formulations. Biphasic dissolution tests indicated that all four formulations had faster release profiles compared to the SOL/ITZ solid dispersion. Formulations of HPβCD 0.63 and Rameb ® even reached 95% of ITZ released in both phases after 1h. The formulations were characterized using thermal differential scanning calorimetry and attenuated total reflectance infra-red analysis. These analyses confirmed that the increased release profile was due to the formation of ternary inclusion complexes. Copyright © 2016 Elsevier B.V. All rights reserved.

The role of capital realignment versus in situ stabilization for the treatment of slipped capital femoral epiphysis.

PubMed

Souder, Christopher D; Bomar, James D; Wenger, Dennis R

2014-12-01

Slipped capital femoral epiphysis (SCFE) can be treated by a variety of methods with the traditional method of in situ pin fixation being most commonly used. More recently, the Modified Dunn (Mod. Dunn) procedure consisting of capital realignment has been popularized as a treatment method for SCFE, particularly for more severe cases. Over the last 5 years, our institution has selectively used this method for more complex cases. The purpose of this article is to evaluate the differences between these 2 treatment methods in terms of avascular necrosis (AVN) rate, reoperation rate, and complication rate. Eighty-eight hips that were surgically treated for SCFE between July 2004 and June 2012 met our inclusion criteria. The in situ fixation group included 71 hips, whereas 17 hips were anatomically reduced with the Mod. Dunn procedure. Loder classification, severity, acuity, complication rate, and reoperation rate were determined for the 2 cohorts. The χ analysis was performed to evaluate the relationship between the treatment method and outcome. As expected, stable slips did well with in situ pinning with no cases of AVN, even in more severe slips. Ten stable slips were treated with the Mod. Dunn approach and 2 (20%) developed AVN. Unstable slips were more difficult to treat with 3 of the 7 hips stabilized in situ developing AVN (43%). Two of the 7 unstable slips treated by the Mod. Dunn procedure developed AVN (29%). The other outcomes studied (reoperation rate and complication rate) were not significantly related to the surgical treatment method (P = 0.732 and 0.261, respectively). In situ pinning remains a safe and predictable method for treatment of stable SCFE with no AVN noted, even in severe slips. Attempts to anatomically reduce stable slips led to severe AVN in 20% of cases, thus this treatment approach should be considered with caution. Treatment of unstable slips remains problematic with high AVN rates noted whether treated by in situ fixation or capital realignment (Mod. Dunn). Level III retrospective comparative study.

ESR study of the molecular orientation and dynamics of stable organic radicals included in the 1-D organic nanochannels of 2,4,6-tris-4-(chlorophenoxy)-1,3,5-triazine.

PubMed

Kobayashi, Hirokazu; Asaji, Tetsuo; Tani, Atsushi

2012-03-01

The molecular orientation and dynamics of the organic stable radicals such as 2,2,6,6-tetramethyl-1-piperidinyl-1-oxyl (TEMPO) or 4-hydroxy-TEMPO (TEMPOL) included in the one-dimensional (1-D) organic nanochannels of 2,4,6-tris-4-(chlorophenoxy)-1,3,5-triazine (CLPOT) were investigated by examining the inclusion compounds (ICs) diluted by the co-inclusion of non-radicals using ESR spectroscopy. Spectral simulation showed that the axial rotation of TEMPO or TEMPOL molecules is excited in the nanochannels with activation energies of 8 and 7 kJ mol(-1) , respectively. The rotation axis was estimated to be tilted towards the principal x direction in the axis system of the g-tensor of the respective radicals. This is quite different from that for similar ICs in the nanochannels of tris(o-phenylenedioxy)cyclotriphosphazene (TPP), in which the radicals are axially rotating around the principal axis y of the g-tensor. The difference is attributed to the larger nanospace of the CLPOT nanochannels. Copyright © 2012 John Wiley & Sons, Ltd.

Formation of distinct inclusion bodies by inhibition of ubiquitin-proteasome and autophagy-lysosome pathways.

PubMed

Lee, Junho; Yang, Kyu-Hwan; Joe, Cheol O; Kang, Seok-Seong

2011-01-14

Accumulation of misfolded proteins is caused by the impairment of protein quality control systems, such as ubiquitin-proteasome pathway (UPP) and autophagy-lysosome pathway (ALP). In this study, the formation of inclusion bodies was examined after the blockade of UPP and/or ALP in A549 cells. UPP inhibition induced a single and large inclusion body localized in microtubule-organizing center. Interestingly, however, ALP inhibition generated dispersed small inclusion bodies in the cytoplasm. Tuberous sclerosis complex 2 was selectively accumulated in the inclusion bodies of UPP-inhibited cells, but not those of ALP-inhibited cells. Blockade of transcription and translation entirely inhibited the formation of inclusion body induced by UPP inhibition, but partially by ALP inhibition. Moreover, the simultaneous inhibition of two protein catabolic pathways independently developed two distinct inclusion bodies within a single cell. These findings clearly demonstrated that dysfunction of each catabolic pathway induced formation and accumulation of unique inclusion bodies on the basis of morphology, localization and formation process in A549 cells. Copyright © 2010 Elsevier Inc. All rights reserved.

Minerals and melt inclusions as keys to understanding magma reservoir processes during formation of volcanic and plutonic mafic-ultramafic complexes in the Maimecha Kotui Province (Polar Siberia)

NASA Astrophysics Data System (ADS)

Simonov, Vladimir; Vasiliev, Yurii; Kotlyarov, Alexey; Stupakov, Sergey

2016-04-01

Magmatic complexes in the Maimecha Kotui Province (Polar Siberia) attract attention of researchers because they contain ultramafic volcanic rocks - meimechites, being products of crystallization of the ultrabasic deep mantle melts (Sobolev et al., 1991, 2009, 2011; Ryabchikov et al., 2002; Vasiliev, Gora, 2014). Effusive meimechites together with intrusive dunites of the Guli massif form ancient (253-246 Ma) volcanic and plutonic association, in which also pyroxenites and alkaline rocks are situated. Conditions of formation of this association were established with the help of minerals and melt inclusions study. The cumulative structure of the Guli massif dunites consists of rather large (2-4 mm) olivine crystals and dividing them zones (0.5-0.7 mm), filled with fine grains of clinopyroxenes and ore minerals (magnetite, ilmenite and chromite). The extended forms of well faceted pyroxene crystals testify to their fast growth from melt between cumulative olivines. Thus, crystallization of clinopyroxenes and ore minerals leads to formation between olivines ore pyroxenites, which are presented in the Guli massif by independent bodies. Analysis of olivine, Cr-spinel and clinopyroxene compositions testify to similarity of conditions of the Guli massif dunites crystallization on the one hand with formation of platinum-bearing Uralian-Alaskan-type mafic-ultramafic complexes and with another - show participation of meimechite magma. Major element composition of melt inclusions in Cr-spinel has shown that dunites of the Guli massif were crystallized with participation of subalkaline picrite magmatic systems, that are relative to melts, responsible of formation of platinum-bearing mafic-ultramafic complexes and meimechites. Peculiarities of trace and rare-earth elements distribution in melt inclusions in Cr-spinel of dunites are actually similar to inclusions in olivine of meimechites. Overall, data on composition of inclusions directly testify to formation of considered dunites from ultrabasic melt close to meimechite magma. The affinity of melts, forming dunites and meimechites, is confirmed by computer simulations, shown high crystallization temperature of olivines from dunites (1590-1415°C) (Simonov et al., 2014, 2015), actually coinciding with data on olivines from meimechite - 1600-1420°C (Sobolev et al., 1991, 2009). A part of this ultrabasic melts was crystallized in the magma chambers (with formation of cumulative dunites) and another part - came up to a surface with formation of effusive meimechites. Presence in Cr-spinels from Guli massif dunites melt inclusions with rather large (up to 50 μm) well faceted olivine crystals, situated in the quenching fine-grained association of minerals (clinopyroxene, feldspar and nepheline), testifies to change of a quiet mode of crystallization by sharp falling of parameters of magma during olivine cumulation in the magma chamber, that resulted in appearance of alkaline rocks. As a whole, minerals and melt inclusions study testify to formation of volcanic and plutonic complexes in the Maimecha Kotui Province (Polar Siberia) as a result of evolution of primary deep mantle ultrabasic melts (similar by its chemical composition to meimechites) during cumulative processes in the magma chambers.

Theoretical study of X⁻ · 1 · YF (1 = triazine, X = Cl, Br and I, Y = H, Cl, Br, I, PH₂ and AsH₂): noncovalently electron-withdrawing effects on anion-arene interactions.

PubMed

Chen, Yishan; Yao, Lifeng

2014-01-01

The ternary complexes X(-) · 1 · YF (1 = triazine, X = Cl, Br and I, Y = H, Cl, Br, I, PH2 and AsH2) have been investigated by MP2 calculations to understand the noncovalently electron-withdrawing effects on anion-arene interactions. The results indicate that in binary complexes (1 · X(-)), both weak σ-type and anion-π complexes can be formed for Cl(-) and Br(-), but only anion-π complex can be formed for I(-). Moreover, the hydrogen-bonding complex is the global minimum for all three halides in binary complexes. However, in ternary complexes, anion-π complex become unstable and only σ complex can retain in many cases for Cl(-) and Br(-). Anion-π complex keeps stable only when YF = HF. In contrast with binary complexes, σ complex become the global minimum for Cl(-) and Br(-) in ternary complexes. These changes in binding mode and strength are consistent with the results of covalently electron-withdrawing effects. However, in contrast with the covalently electron-withdrawing substituents, Cl(-) and Br(-) can attack the aromatic carbon atom to form a strong σ complex when the noncovalently electron-withdrawing effect is induced by halogen bonding. The binding behavior for I(-) is different from that for Cl(-) and Br(-) in two aspects. First, the anion-π complex for I(-) can also keep stable when the noncovalent interaction is halogen bonding. Second, the anion-π complex for I(-) is the global minimum when it can retain as a stable structure.

Design, synthesis, and biological evaluation of air-stable nafuredin-γ analogs as complex I inhibitors.

PubMed

Ohtawa, Masaki; Matsunaga, Mari; Fukunaga, Keiko; Shimizu, Risa; Shimizu, Eri; Arima, Shiho; Ohmori, Junko; Kita, Kiyoshi; Shiomi, Kazuro; Omura, Satoshi; Nagamitsu, Tohru

2015-03-01

Nafuredin-γ (2), converted from nafuredin (1) under mild basic conditions, demonstrates potent and selective inhibitory activity against helminth complex I. However, 2 is unstable in air because the conjugated dienes are oxygen-labile. To address this, we designed and synthesized air-stable nafuredin-γ analogs. Although the complex I inhibitory activities of all the new nafuredin-γ analogs were lower than that of 2, all were in the high nM range (IC50: 300-820nM). Copyright © 2015 Elsevier Ltd. All rights reserved.

Synthesis of the first radiolabeled 188Re N-heterocyclic carbene complex and initial studies on its potential use in radiopharmaceutical applications

PubMed Central

Wagner, Thomas; Zeglis, Brian M.; Groveman, Sam; Hille, Claudia; Pöthig, Alexander; Francesconi, Lynn C.; Herrmann, Wolfgang A.; Kühn, Fritz E.; Reiner, Thomas

2015-01-01

A novel approach towards the synthesis of radiolabeled organometallic rhenium complexes is presented. We successfully synthesized and analyzed the first 188Re-labeled N-heterocyclic biscarbene complex, trans-dioxobis(1,1′-methylene-bis(3,3′-diisopropylimidazolium-2-ylidene))188rhenium(V) hexafluorophosphate (188Re-4) via transmetalation using an air-stable and moisture-stable silver(I) biscarbene complex. In order to assess the viability of this complex as a potential lead structure for in vivo applications, the stability of the 188Re-NHC complex was tested in physiologically relevant media. Ultimately, our studies illustrate that the complex we synthesized dissociates rapidly and is therefore unsuitable for use in radiopharmaceuticals. However, it is clear that the transmetalation approach we have developed is a rapid, robust, and mild method for the synthesis of new 188Re-labeled carbene complexes. PMID:24889257

Dynamic transverse shear modulus for a heterogeneous fluid-filled porous solid containing cylindrical inclusions

NASA Astrophysics Data System (ADS)

Song, Yongjia; Hu, Hengshan; Rudnicki, John W.; Duan, Yunda

2016-09-01

An exact analytical solution is presented for the effective dynamic transverse shear modulus in a heterogeneous fluid-filled porous solid containing cylindrical inclusions. The complex and frequency-dependent properties of the dynamic shear modulus are caused by the physical mechanism of mesoscopic-scale wave-induced fluid flow whose scale is smaller than wavelength but larger than the size of pores. Our model consists of three phases: a long cylindrical inclusion, a cylindrical shell of poroelastic matrix material with different mechanical and/or hydraulic properties than the inclusion and an outer region of effective homogeneous medium of laterally infinite extent. The behavior of both the inclusion and the matrix is described by Biot's consolidation equations, whereas the surrounding effective medium which is used to describe the effective transverse shear properties of the inner poroelastic composite is assumed to be a viscoelastic solid whose complex transverse shear modulus needs to be determined. The determined effective transverse shear modulus is used to quantify the S-wave attenuation and velocity dispersion in heterogeneous fluid-filled poroelastic rocks. The calculation shows the relaxation frequency and relative position of various fluid saturation dispersion curves predicted by this study exhibit very good agreement with those of a previous 2-D finite-element simulation. For the double-porosity model (inclusions having a different solid frame than the matrix but the same pore fluid as the matrix) the effective shear modulus also exhibits a size-dependent characteristic that the relaxation frequency moves to lower frequencies by two orders of magnitude if the radius of the cylindrical poroelastic composite increases by one order of magnitude. For the patchy-saturation model (inclusions having the same solid frame as the matrix but with a different pore fluid from the matrix), the heterogeneity in pore fluid cannot cause any attenuation in the transverse shear modulus at all. A comparison with the case of spherical inclusions illustrates that the transverse shear modulus for the cylindrical inclusion exhibits more S-wave attenuation than spherical inclusions.

The development of a stable, coated pellet formulation of a water-sensitive drug, a case study: development of a stable core formulation.

PubMed

Fitzpatrick, Shaun; Taylor, Scott; Booth, Steven W; Newton, Michael J

2006-01-01

A development program has been carried out to provide a stable extrusion/spheronisation pellet formulation for a highly water-soluble drug, sitagliptin, which undergoes a change in physical form on processing and is subject to hydrolytic decomposition. A conventional extrusion/spheronization formulation resulted in significant degradation of the drug. The inclusion of glyceryl monostearate into the formulation was found to reduce the water levels required to such a level that there was no significant degradation of the drug during processing to form pellets. The use of a ram extruder to screen formulations with small quantities minimizes the need for the drug in the formulation-screening process, and the results from this method of extrusion were found to be translatable to the use of a screen extruder, which allowed scale-up of the process.

Process for producing an aggregate suitable for inclusion into a radiation shielding product

DOEpatents

Lessing, Paul A.; Kong, Peter C.

2000-01-01

The present invention is directed to methods for converting depleted uranium hexafluoride to a stable depleted uranium silicide in a one-step reaction. Uranium silicide provides a stable aggregate material that can be added to concrete to increase the density of the concrete and, consequently, shield gamma radiation. As used herein, the term "uranium silicide" is defined as a compound generically having the formula U.sub.x Si.sub.y, wherein the x represents the molecules of uranium and the y represent the molecules of silicon. In accordance with the present invention, uranium hexafluoride is converted to a uranium silicide by contacting the uranium hexafluoride with a silicon-containing material at a temperature in a range between about 1450.degree. C. and about 1750.degree. C. The stable depleted uranium silicide is included as an aggregate in a radiation shielding product, such as a concrete product.

Isolated glyoxylic acid-water 1:1 complexes in low temperature argon matrices.

PubMed

Lundell, Jan; Olbert-Majkut, Adriana

2015-02-05

The 1:1 hydrogen bonded complexes between glyoxylic acid (GA) and water are studied in low temperature argon matrices. Four different complex structures were found in deposited matrices. The lowest energy conformer (T1) of GA was found to form complex, where the water molecule was attached to the opposite side of the intramolecular hydrogen bond in the molecule (T1B). Interestingly, this complex was estimated to be+8.0 kJ mol(-1) higher in energy than the most stable structure (T1A), where the water is inserted into the internal hydrogen bond, and also found in solid argon but in smaller abundance. For the second-lowest energy conformer of GA (T2), the two lowest-energy complex structures were identified, with the most stable complex structure (T2A) also being the most abundant in the matrices. The difference between experiment and computational energetic order of the two complex structures of the same GA conformer is explained by contributions of deformation energy upon complexation and the effect of the environment. The computed BSSE-corrected interaction energies are for the two most stable complexes of the two GA conformers for T1A and T2A -42.11 and -45.03 kJ mol(-1), respectively, at the CCSD(T)/aug-cc-pVTZ//B3LYP/aug-cc-pVTZ level of theory. Copyright © 2013 Elsevier B.V. All rights reserved.

ELSiTO. a collaborative European initiative to foster social inclusion with persons experiencing mental illness.

PubMed

Ammeraal, M; Kantartzis, S; Burger, M; Bogeas, T; van der Molen, C; Vercruysse, L

2013-06-01

ELSiTO (Empowering Learning for Social Inclusion Through Occupation), an international collaborative partnership, with over 30 members from Belgium, Greece and the Netherlands, aimed to explore the nature and processes of social inclusion for persons experiencing mental illness. Members included persons experiencing mental illness and health professionals. Four international visits and local activities enabled a knowledge creation process that combined the experience of social inclusion as we lived and worked together with exploration of the processes of community projects, narratives of experiences and reflective workshops. Outcomes included identification and description of the following: the nature of social inclusion as lived by the participants; the critical elements that support inclusion; and the competences that are developed by all stakeholders during this process. The complex process of social inclusion is facilitated by doing together in environments that enable equality, trust, risk taking and realignment of power. These conceptual understandings of inclusion are discussed in relation to the ongoing activities of the partners, to their potential contribution to the education of occupational therapists (and other professionals) and to the development of socially inclusive occupation-based projects in the community. Copyright © 2013 John Wiley & Sons, Ltd.

A novel stable 3D luminescent uranyl complex for highly efficient and sensitive recognition of Ru3+ and biomolecules

NASA Astrophysics Data System (ADS)

Tian, Hong-Hong; Chen, Liang-Ting; Zhang, Rong-Lan; Zhao, Jian-She; Liu, Chi-Yang; Weng, Ng Seik

2018-02-01

A novel highly stable 3D luminescent uranyl coordination polymer, namely {[UO2(L)]·DMA}n (1), was assembled with uranyl salt and a glycine-derivative ligand [6-(carboxymethyl-amino)-4-oxo-4,5-dihydro-[1,3,5]triazin-2-ylamino]-acetic acid (H2L) under solvothermal reaction. Besides, It was found that complex 1 possesses excellent luminescent properties, particularly the efficient selectivity and sensitivity in the recognition of Ru3+, biomacromolecule bovine serum albumin (BSA), biological small molecules dopamine (DA), ascorbic acid (AA) and uric acid (UA) in the water solution based on a "turn-off" mechanism. Accordingly, the luminescent explorations also demonstrated that complex 1 could be acted as an efficient luminescent probe with high quenching efficiency and low detection limit for selectively detecting Ru3+ and biomolecules (DA, AA, UA and BSA). It was noted that the framework structure of complex 1 still remains highly stable after quenching, which was verified by powder X-ray diffraction (PXRD).

[Study on two preparation methods for beta-CD inclusion compound of four traditional Chinese medicine volatile oils].

PubMed

Li, Hailiang; Cui, Xiaoli; Tong, Yan; Gong, Muxin

2012-04-01

To compare inclusion effects and process conditions of two preparation methods-colloid mill and saturated solution-for beta-CD inclusion compound of four traditional Chinese medicine volatile oils and study the relationship between each process condition and volatile oil physical properties and the regularity of selective inclusion of volatile oil components. Volatile oils from Nardostachyos Radix et Rhizoma, Amomi Fructus, Zingiberis Rhizoma and Angelicaesinensis Radix were prepared using two methods in the orthogonal test. These inclusion compounds by optimized processes were assessed and compared by such methods as TLC, IR and scanning electron microscope. Inclusion oils were extracted by steam distillation, and the components found before and after inclusion were analyzed by GC-MS. Analysis showed that new inclusion compounds, but inclusion compounds prepared by the two processes had differences to some extent. The colloid mill method showed a better inclusion effect than the saturated solution method, indicating that their process conditions had relations with volatile oil physical properties. There were differences in the inclusion selectivity of components between each other. The colloid mill method for inclusion preparation is more suitable for industrial requirements. To prepare volatile oil inclusion compounds with heavy gravity and high refractive index, the colloid mill method needs longer time and more water, while the saturated solution method requires higher temperature and more beta-cyclodextrin. The inclusion complex prepared with the colloid mill method contains extended molecular weight chemical composition, but the kinds of components are reduced.

Construction and Characterization of a Chitosan-Immobilized-Enzyme and β-Cyclodextrin-Included-Ferrocene-Based Electrochemical Biosensor for H2O2 Detection

PubMed Central

Dong, Wenbo; Wang, Kaiyin; Chen, Yu; Li, Weiping; Ye, Yanchun; Jin, Shaohua

2017-01-01

An electrochemical detection biosensor was prepared with the chitosan-immobilized-enzyme (CTS-CAT) and β-cyclodextrin-included-ferrocene (β-CD-FE) complex for the determination of H2O2. Ferrocene (FE) was included in β-cyclodextrin (β-CD) to increase its stability. The structure of the β-CD-FE was characterized. The inclusion amount, inclusion rate, and electrochemical properties of inclusion complexes were determined to optimize the reaction conditions for the inclusion. CTS-CAT was prepared by a step-by-step immobilization method, which overcame the disadvantages of the conventional preparation methods. The immobilization conditions were optimized to obtain the desired enzyme activity. CTS-CAT/β-CD-FE composite electrodes were prepared by compositing the CTS-CAT with the β-CD-FE complex on a glassy carbon electrode and used for the electrochemical detection of H2O2. It was found that the CTS-CAT could produce a strong reduction peak current in response to H2O2 and the β-CD-FE could amplify the current signal. The peak current exhibited a linear relationship with the H2O2 concentration in the range of 1.0 × 10−7–6.0 × 10−3 mol/L. Our work provided a novel method for the construction of electrochemical biosensors with a fast response, good stability, high sensitivity, and a wide linear response range based on the composite of chitosan and cyclodextrin. PMID:28773229

Young children's communication and literacy: a qualitative study of language in the inclusive preschool.

PubMed

Kliewer, C

1995-06-01

Interactive and literacy-based language use of young children within the context of an inclusive preschool classroom was explored. An interpretivist framework and qualitative research methods, including participant observation, were used to examine and analyze language in five preschool classes that were composed of children with and without disabilities. Children's language use included spoken, written, signed, and typed. Results showed complex communicative and literacy language use on the part of young children outside conventional adult perspectives. Also, children who used expressive methods other than speech were often left out of the contexts where spoken language was richest and most complex.

Influence of valine enantiomer configuration on the molecular dynamics simulation of their separation by β-cyclodextrin

NASA Astrophysics Data System (ADS)

Alvira, Elena

2017-07-01

The influence of enantiomeric configurations on the separation of valine by β-cyclodextrin with different solvents, is analysed by a molecular dynamics simulation at constant temperature. Different methods to select the initial dispositions of valine enantiomers in the trajectories are proposed, and their influence on the interaction energy, residence time, elution order and capacity to form inclusion complexes is studied. The residence time is the most influenced quantity, whereas the capacity to form inclusion complexes is hardly affected by enantiomeric dispositions. In any case, guests tend to locate in the same areas of β-cyclodextrin but with different orientations according to disposition.

Electrospinning of cyclodextrin/linalool-inclusion complex nanofibers: Fast-dissolving nanofibrous web with prolonged release and antibacterial activity.

PubMed

Aytac, Zeynep; Yildiz, Zehra Irem; Kayaci-Senirmak, Fatma; Tekinay, Turgay; Uyar, Tamer

2017-09-15

The volatility and limited water solubility of linalool is a critical issue to be solved. Here, we demonstrated the electrospinning of polymer-free nanofibrous webs of cyclodextrin/linalool-inclusion complex (CD/linalool-IC-NFs). Three types of modified cyclodextrin (HPβCD, MβCD, and HPγCD) were used to electrospin CD/linalool-IC-NFs. Free-standing CD/linalool-IC-NFs facilitate maximum loading of linalool up to 12% (w/w). A significant amount of linalool (45-89%) was preserved in CD/linalool-IC-NFs, due to enhancement in the thermal stability of linalool by cyclodextrin inclusion complexation. Remarkably, CD/linalool-IC-NFs have shown fast-dissolving characteristics in which these nanofibrous webs dissolved in water within two seconds. Furthermore, linalool release from CD/linalool-IC-NFs inhibited growth of model Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria to a great extent. Briefly, characteristics of liquid linalool have been preserved in a solid nanofiber form and designed CD/linalool-IC-NFs confer high loading capacity, enhanced shelf life and strong antibacterial activity of linalool. Copyright © 2017 Elsevier Ltd. All rights reserved.

Electrochemical and surface plasmon resonance characterization of β-cyclodextrin-based self-assembled monolayers and evaluation of their inclusion complexes with glucocorticoids

NASA Astrophysics Data System (ADS)

Frasconi, Marco; Mazzei, Franco

2009-07-01

This paper describes the characterization of a self-assembled β-cyclodextrin (β-CD)-derivative monolayer (β-CD-SAM) on a gold surface and the study of their inclusion complexes with glucocorticoids. To this aim the arrangement of a self-assembled β-cyclodextrin-derivative monolayer on a gold surface was monitored in situ by means of surface plasmon resonance (SPR) spectroscopy and double-layer capacitance measurements. Film thickness and dielectric constant were evaluated for a monolayer of β-CD using one-color-approach SPR. The selectivity of the β-CD host surface was verified by using electroactive species permeable and impermeable in the β-CD cavity. The redox probe was selected according to its capacity to permeate the β-CD monolayer and its electrochemical behavior. In order to evaluate the feasibility of an inclusion complex between β-CD-SAM with some steroids such as cortisol and cortisone, voltammetric experiments in the presence of the redox probes as molecules competitive with the steroids have been performed. The formation constant of the surface host-guest by β-CD-SAM and the steroids under study was calculated.

The effect of mechanical grinding on the formation, crystalline changes and dissolution behaviour of the inclusion complex of telmisartan and β-cyclodextrins.

PubMed

Borba, Paola Aline Amarante; Pinotti, Marihá; Andrade, George Ricardo Santana; da Costa, Nivan Bezerra; Olchanheski Junior, Luiz Renato; Fernandes, Daniel; de Campos, Carlos Eduardo Maduro; Stulzer, Hellen Karine

2015-11-20

Telmisartan (TEL) was entrapped into β-cyclodextrin aiming the improvement of its biopharmaceutical properties of low solubility. A solid state grinding process was used to prepare the molecular inclusion complex (MIC) for up to 30min. The inclusion ratio of drug and β-cyclodextrin was established as 1:2 and 1:3 (mol/mol) by phase solubility study and Job Plot. DSC, XRPD and FTIR confirmed the molecular interactions between TEL and β-cyclodextrin. Computer molecular modeling supports the presence of hydrogen bonds between guest and host and demonstrated the most probable complexes configuration. MIC_1:2_30 and MIC_1:3_30 enhanced the dissolution rate of the drug achieving a delivery rate comparable with the reference medicine available in the market (81% and 87% in 5min, for MIC_1:3_30 and Micardis(®), respectively). These formulations showed rapid and effective antihypertensive effect against angiotensin II in rats up to 180min, with statistically significant results against placebo and control in the first 30min after administration. Copyright © 2015 Elsevier Ltd. All rights reserved.

Spectrofluorometric Determination of Putrescine: Optimization of the Putrescine-Orthophthaldehyde Complex Using Spectrofluorometry.

PubMed

Oyelakin, Oladele; Traoré, Moumouny; Mbye, El Hadji Babacar; Khonté, Abdourahmane; Cisse, Lamine; Faye, Abdoulaye N; Faye, Ousman; Mbaye, Moussa; Kital, Khemesse; Gaye-Seye, Mame Diabou; Coly, Atanasse; Tine, Alphonse; Delattre, François

2016-11-01

In alkaline medium, the complex formed between putrescine and orthophthalaldehyde was studied using spectrofluorescence. The derivative is kinetically stable 24 h after complexation. The stoichiometry of the complex is 1:1 at maximum fluorescence intensity, also 24 h after complexation.

Mineralogy, textures and mode of formation of a hibonite-bearing Allende inclusion

NASA Technical Reports Server (NTRS)

Allen, J. M.; Grossman, L.; Davis, A. M.; Hutcheon, I. D.

1978-01-01

The origin of a Type A, hibonite-rich, coarse-grained inclusion is investigated with the electron microprobe and petrographic and scanning electron microscopes. The primary phases are hibonite, rhonite, Ti-Al-pyroxene, spinel, perovskite and melilite. Evidence for the crystallization of the bulk of the primary phases, hibonite and melilite, from a melt is lacking, suggesting that they may have condensed directly from a solar nebular gas instead. Primary phases were intensely altered during a later condensation event which deposited grossular, anorthite, nepheline and wollastonite in veins and cavities. Four or five condensate rims were deposited as successive layers on the outside of the inclusion. From inside to outside, they consist of perovskite + spinel, nepheline + anorthite, Ti-Al-pyroxene + diopside, hedenbergite + or - wollastonite + or - andradite and, finally, prisms of diopside and hedenbergite with wollastonite and andradite. Reverse zoning in melilite; alteration phases and rim phases, which are not stable condensates from a gas of solar composition; and details of the sequence of rim condensates all suggest that the entire condensation history of this inclusion was interrupted by changes in pressure and/or temperature and/or gas phase composition.

Precipitation Behaviors of TiN Inclusion in GCr15 Bearing Steel Billet

NASA Astrophysics Data System (ADS)

Tian, Qianren; Wang, Guocheng; Zhao, Yang; Li, Jing; Wang, Qi

2018-06-01

There are many types of non-metallic TiN-based inclusions observed in GCr15 bearing steel, including single-particle TiN, multi-particle polymerized TiN, and complex inclusions like TiN-MnS, TiN-MgO-MgAl2O4 (TiN-MgO-MA), and TiN-MgAl2O4-MnS (TiN-MA-MnS). Thermodynamic calculations suggest that single-particle TiN precipitates dominate the mushy zone of GCr15 bearing steel. Kinetic calculations regarding TiN growth suggest that the final size of the single-particle TiN ranges between 1 and 6 μm in the initial concentration range of [pct Ti] = 0.0060 to 0.0079 and [pct N] = 0.0049 to 0.0070, at 1620 to 1640 K and a local cooling rate of 0.5 to 10 K/s. The multi-particle polymerized TiN are formed by single TiN particles in three stages: single-particle TiN inclusions approach each other drawn by the cavity bridge force (CBF), local active angles consolidate, and neck region sintering occurs. Based on the thermodynamic calculations of TiN, MnS, and MgO precipitation, the formation behaviors of complex inclusions of TiN-MnS, TiN-MgO-MA, and TiN-MA-MnS were investigated.

Extremely stable soluble high molecular mass multi-protein complex with DNase activity in human placental tissue.

PubMed

Burkova, Evgeniya E; Dmitrenok, Pavel S; Sedykh, Sergey E; Buneva, Valentina N; Soboleva, Svetlana E; Nevinsky, Georgy A

2014-01-01

Human placenta is an organ which protects, feeds, and regulates the grooving of the embryo. Therefore, identification and characterization of placental components including proteins and their multi-protein complexes is an important step to understanding the placenta function. We have obtained and analyzed for the first time an extremely stable multi-protein complex (SPC, ∼ 1000 kDa) from the soluble fraction of three human placentas. By gel filtration on Sepharose-4B, the SPC was well separated from other proteins of the placenta extract. Light scattering measurements and gel filtration showed that the SPC is stable in the presence of NaCl, MgCl2, acetonitrile, guanidinium chloride, and Triton in high concentrations, but dissociates efficiently in the presence of 8 M urea, 50 mM EDTA, and 0.5 M NaCl. Such a stable complex is unlikely to be a casual associate of different proteins. According to SDS-PAGE and MALDI mass spectrometry data, this complex contains many major glycosylated proteins with low and moderate molecular masses (MMs) 4-14 kDa and several moderately abundant (79.3, 68.5, 52.8, and 27.2 kDa) as well as minor proteins with higher MMs. The SPC treatment with dithiothreitol led to a disappearance of some protein bands and revealed proteins with lower MMs. The SPCs from three placentas efficiently hydrolyzed plasmid supercoiled DNA with comparable rates and possess at least two DNA-binding sites with different affinities for a 12-mer oligonucleotide. Progress in study of placental protein complexes can promote understanding of their biological functions.

Enantioseparation of mandelic acid derivatives by high performance liquid chromatography with substituted β-cyclodextrin as chiral mobile phase additive and evaluation of inclusion complex formation

PubMed Central

Tong, Shengqiang; Zhang, Hu; Shen, Mangmang

2014-01-01

The enantioseparation of ten mandelic acid derivatives was performed by reverse phase high performance liquid chromatography with hydroxypropyl-β-cyclodextrin (HP-β-CD) or sulfobutyl ether-β-cyclodextrin (SBE-β-CD) as chiral mobile phase additives, in which inclusion complex formations between cyclodextrins and enantiomers were evaluated. The effects of various factors such as the composition of mobile phase, concentration of cyclodextrins and column temperature on retention and enantioselectivity were studied. The peak resolutions and retention time of the enantiomers were strongly affected by the pH, the organic modifier and the type of β-cyclodextrin in the mobile phase, while the concentration of buffer solution and temperature had a relatively low effect on resolutions. Enantioseparations were successfully achieved on a Shimpack CLC-ODS column (150×4.6 mm i.d., 5 μm). The mobile phase was a mixture of acetonitrile and 0.10 mol L-1 of phosphate buffer at pH 2.68 containing 20 mmol L-1 of HP-β-CD or SBE-β-CD. Semi-preparative enantioseparation of about 10 mg of α-cyclohexylmandelic acid and α-cyclopentylmandelic acid were established individually. Cyclodextrin-enantiomer complex stoichiometries as well as binding constants were investigated. Results showed that stoichiomertries for all the inclusion complex of cyclodextrin-enantiomers were 1:1. PMID:24893270

Including Thermal Fluctuations in Actomyosin Stable States Increases the Predicted Force per Motor and Macroscopic Efficiency in Muscle Modelling

PubMed Central

2016-01-01

Muscle contractions are generated by cyclical interactions of myosin heads with actin filaments to form the actomyosin complex. To simulate actomyosin complex stable states, mathematical models usually define an energy landscape with a corresponding number of wells. The jumps between these wells are defined through rate constants. Almost all previous models assign these wells an infinite sharpness by imposing a relatively simple expression for the detailed balance, i.e., the ratio of the rate constants depends exponentially on the sole myosin elastic energy. Physically, this assumption corresponds to neglecting thermal fluctuations in the actomyosin complex stable states. By comparing three mathematical models, we examine the extent to which this hypothesis affects muscle model predictions at the single cross-bridge, single fiber, and organ levels in a ceteris paribus analysis. We show that including fluctuations in stable states allows the lever arm of the myosin to easily and dynamically explore all possible minima in the energy landscape, generating several backward and forward jumps between states during the lifetime of the actomyosin complex, whereas the infinitely sharp minima case is characterized by fewer jumps between states. Moreover, the analysis predicts that thermal fluctuations enable a more efficient contraction mechanism, in which a higher force is sustained by fewer attached cross-bridges. PMID:27626630

Novel Processing of Boron Carbide (B4C): Plasma Synthesized Nano Powders and Pressureless Sintering Forming of Complex Shapes

DTIC Science & Technology

2008-12-01

Figure 4. B4C plates formed via hot pressing with a curved shape. Commercial B4C shows a large number of lenticular graphitic inclusions, Figure 5...materials and they act as crack initiation points in flexure testing. Figure 5. SEM micrograph showing large lenticular graphitic inclusions in commercial

Learning about protein solubility from bacterial inclusion bodies

PubMed Central

Martínez-Alonso, Mónica; González-Montalbán, Nuria; García-Fruitós, Elena; Villaverde, Antonio

2009-01-01

The progressive solving of the conformation of aggregated proteins and the conceptual understanding of the biology of inclusion bodies in recombinant bacteria is providing exciting insights on protein folding and quality. Interestingly, newest data also show an unexpected functional and structural complexity of soluble recombinant protein species and picture the whole bacterial cell factory scenario as more intricate than formerly believed. PMID:19133126

The Inclusive Educational Process of Students with Visual Impairments in Spain: An Analysis from the Perspective of Organizations

ERIC Educational Resources Information Center

Simon, Cecilia; Echeita, Gerardo; Sandoval, Marta; Lopez, Mauricio

2010-01-01

Inclusive education is a complex and multidimensional process that, among other aspirations, tries to foster the rights of every student to obtain a high-quality education. This process focuses on the diversity of needs of all students by increasing participation in learning, cultures, and communities and reducing exclusion within and from…

A study on the spectroscopy and photophysics of 4-hydroxy-3-methoxybenzoic acid in different solvents, pH and β-cyclodextrin

NASA Astrophysics Data System (ADS)

Stalin, T.; Rajendiran, N.

2006-08-01

Effect of solvents, buffer solutions of different pH and β-cyclodextrin (β-CD) on the absorption and fluorescence spectra of 4-hydroxy-3-methoxybenzoic acid (vanillic acid, HMB) have been investigated and compared with 4-hydroxy-3,5-dimethoxybenzoic acid (HDMB). The inclusion complex of β-CD with HMB is investigated by UV-vis, fluorimetry, FT-IR, 1H NMR, scanning electron microscope (SEM) and semiempirical methods. The thermodynamic parameters (Δ G, Δ H and Δ S) of inclusion process are also determined. Solvent study shows in the S 0 state, HMB is more polar than HDMB, whereas the polarity is same in the S 1 state. pH studies suggest proton transfer reactions follow the same trend in HMB and HDMB molecules. β-CD studies indicates (i) HMB forms 1:1 inclusion complex with β-CD and (ii) unusual blue shift of hydroxyl ion (dianion) in the β-CD medium confirms OH group present in the interior part of the β-CD cavity and COOH group present in the upper part of the β-CD cavity. A mechanism is proposed to explain the inclusion process.

Iterative Monte Carlo analysis of spin-dependent parton distributions

DOE PAGES

Sato, Nobuo; Melnitchouk, Wally; Kuhn, Sebastian E.; ...

2016-04-05

We present a comprehensive new global QCD analysis of polarized inclusive deep-inelastic scattering, including the latest high-precision data on longitudinal and transverse polarization asymmetries from Jefferson Lab and elsewhere. The analysis is performed using a new iterative Monte Carlo fitting technique which generates stable fits to polarized parton distribution functions (PDFs) with statistically rigorous uncertainties. Inclusion of the Jefferson Lab data leads to a reduction in the PDF errors for the valence and sea quarks, as well as in the gluon polarization uncertainty at x ≳ 0.1. Furthermore, the study also provides the first determination of the flavor-separated twist-3 PDFsmore » and the d 2 moment of the nucleon within a global PDF analysis.« less

Deformation and the timing of gas generation and migration in the eastern Brooks Range foothills, Arctic National Wildlife Refuge, Alaska

USGS Publications Warehouse

Parris, T.M.; Burruss, R.C.; O'Sullivan, P. B.

2003-01-01

Along the southeast border of the 1002 Assessment Area in the Arctic National Wildlife Refuge, Alaska, an explicit link between gas generation and deformation in the Brooks Range fold and thrust belt is provided through petrographic, fluid inclusion, and stable isotope analyses of fracture cements integrated with zircon fission-track data. Predominantly quartz-cemented fractures, collected from thrusted Triassic and Jurassic rocks, contain crack-seal textures, healed microcracks, and curved crystals and fluid inclusion populations, which suggest that cement growth occurred before, during, and after deformation. Fluid inclusion homogenization temperatures (175-250??C) and temperature trends in fracture samples suggest that cements grew at 7-10 km depth during the transition from burial to uplift and during early uplift. CH4-rich (dry gas) inclusions in the Shublik Formation and Kingak Shale are consistent with inclusion entrapment at high thermal maturity for these source rocks. Pressure modeling of these CH4-rich inclusions suggests that pore fluids were overpressured during fracture cementation. Zircon fission-track data in the area record postdeposition denudation associated with early Brooks Range deformation at 64 ?? 3 Ma. With a closure temperature of 225-240??C, the zircon fission-track data overlap homogenization temperatures of coeval aqueous inclusions and inclusions containing dry gas in Kingak and Shublik fracture cements. This critical time-temperature relationship suggests that fracture cementation occurred during early Brooks Range deformation. Dry gas inclusions suggest that Shublik and Kingak source rocks had exceeded peak oil and gas generation temperatures at the time structural traps formed during early Brooks Range deformation. The timing of hydrocarbon generation with respect to deformation therefore represents an important exploration risk for gas exploration in this part of the Brooks Range fold and thrust belt. The persistence of gas high at thermal maturity levels suggests, however, that significant volumes of gas may have been generated.

Complexation of adamantyl compounds by beta-cyclodextrin and monoaminoderivatives.

PubMed

Carrazana, Jorge; Jover, Aida; Meijide, Francisco; Soto, Victor H; Vazquez Tato, José

2005-05-19

Since the beta-cyclodextrin cavity is not a smooth cone but has constrictions in the neighborhoods of the H3 and H5 atoms, the hypothesis that bulky hydrophobic guests can form two isomeric inclusion complexes (one of them, c(p), is formed by the entrance of the guest by the primary side of the cavity, and the other one, c(s), results from the entrance by the secondary side) is checked. Thus, the inclusion processes of two 1-substituted adamantyl derivatives (rimantidine and adamantylmethanol) with beta-cyclodextrin and its two monoamino derivatives at positions 6 (6-NH2beta-CD) and 3 (3-NH2beta-CD) were studied. From rotating-frame Overhauser enhancement spectroscopy experiments, it was deduced that both guests form c(s) complexes with beta-CD and 6-NH2beta-CD but c(p) complexes with 3-NH2beta-CD. In all cases, the hydrophilic group attached to the adamantyl residue protrudes toward the bulk solvent outside the cyclodextrin cavity. The thermodynamic parameters (free energy, equilibrium constant, enthalpy, and entropy) associated with the inclusion phenomena were measured by isothermal titration calorimetry experiments. From these results, the difference in the free energy for the formation of the two complexes, c(s) and c(p), for the same host/guest system has been estimated as being 11.5 +/- 0.8 kJ mol(-1). This large difference explains why under normal experimental conditions only one of the two complexes (c(s)) is detected. It is also concluded that a hyperboloid of revolution can be a better schematic picture to represent the actual geometry of the cyclodextrin cavities than the usual smooth cone or trapezium.

An annotated bibliography of Pyrrone and BBB publications

NASA Technical Reports Server (NTRS)

Burks, H. D.

1972-01-01

This annotated bibliography covers the research and development of two closely related classes of high-temperature polymers, polyimidazopyrrolones (Pyrrone) and bisbenzimidazo-benzophenanthrolines (BBB), from their inception in 1965 through 1971. This compilation of available reference information is not inclusive, but it is sufficiently complete to aid the polymer chemist and materials engineer in the research and development of these two high temperature stable polymeric systems.

The Effectiveness of the Consistency Management & Cooperative Discipline (CMCD) Model as a Student Empowerment and Achievement Enhancer: The Experiences of Two K-12 Inner-City School Systems

ERIC Educational Resources Information Center

Opuni, Kwame A.

2006-01-01

Consistency Management and Cooperative Discipline (CMCD) is a research-based K-12 discipline management program that builds on shared responsibility for learning and classroom organization through the cultivation of democratic and participatory practices that are fair, inclusive, and caring. CMCD seeks to provide a stable and orderly learning…

A stable partitioned FSI algorithm for rigid bodies and incompressible flow. Part I: Model problem analysis

NASA Astrophysics Data System (ADS)

Banks, J. W.; Henshaw, W. D.; Schwendeman, D. W.; Tang, Qi

2017-08-01

A stable partitioned algorithm is developed for fluid-structure interaction (FSI) problems involving viscous incompressible flow and rigid bodies. This added-mass partitioned (AMP) algorithm remains stable, without sub-iterations, for light and even zero mass rigid bodies when added-mass and viscous added-damping effects are large. The scheme is based on a generalized Robin interface condition for the fluid pressure that includes terms involving the linear acceleration and angular acceleration of the rigid body. Added-mass effects are handled in the Robin condition by inclusion of a boundary integral term that depends on the pressure. Added-damping effects due to the viscous shear forces on the body are treated by inclusion of added-damping tensors that are derived through a linearization of the integrals defining the force and torque. Added-damping effects may be important at low Reynolds number, or, for example, in the case of a rotating cylinder or rotating sphere when the rotational moments of inertia are small. In this first part of a two-part series, the properties of the AMP scheme are motivated and evaluated through the development and analysis of some model problems. The analysis shows when and why the traditional partitioned scheme becomes unstable due to either added-mass or added-damping effects. The analysis also identifies the proper form of the added-damping which depends on the discrete time-step and the grid-spacing normal to the rigid body. The results of the analysis are confirmed with numerical simulations that also demonstrate a second-order accurate implementation of the AMP scheme.

LAPAROSCOPIC MANAGEMENT OF RETROPERITONEAL INJURIES IN PENETRATING ABDOMINAL INJURIES.

PubMed

Mosai, F

2017-09-01

Laparoscopy in penetrating abdominal injuries is now accepted and practiced in many modern trauma centres. However its role in evaluating and managing retroperitoneal injuries is not yet well established. The aim of this study was to document our experience in using laparoscopy in a setting of penetrating abdominal injuries with suspected retroperitoneal injury in haemodynamically stable patients. A retrospective descriptive study of prospectively collected data from a trauma unit at Dr George Mukhari Academic Hospital (DGMAH) was done. All haemodynamically stable patients with penetrating abdominal injury who were offered laparoscopy from January 2012 to December 2015 were reviewed and those who met the inclusion criteria were analysed. A total of 284 patients with penetrating abdominal injuries were reviewed and 56 met the inclusion criteria and were analysed. The median age was 30.8 years (15-60 years) and males constituted 87.5% of the study population. The most common mechanism of injury was penetrating stab wounds (62.5%). Forty-five patients (80.3%) were managed laparoscopically, of these n=16 (28.5%) had retroperitoneal injuries that required surgical intervention. The most commonly injured organ was the colon (19.6%). The conversion rate was 19.6% with most common indication for conversion been active bleeding (14%). The complication rate was 7.14% (N=4) and were all Clavien-Dindo grade 3. There were no recorded missed injuries and no mortality. The positive outcomes documented in this study with no missed injuries and absence of mortality suggests that laparoscopy is a feasible option in managing stable patients with suspected retroperitoneal injuries.

A stable partitioned FSI algorithm for rigid bodies and incompressible flow. Part I: Model problem analysis

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

Banks, J. W.; Henshaw, W. D.; Schwendeman, D. W.

A stable partitioned algorithm is developed for fluid-structure interaction (FSI) problems involving viscous incompressible flow and rigid bodies. This added-mass partitioned (AMP) algorithm remains stable, without sub-iterations, for light and even zero mass rigid bodies when added-mass and viscous added-damping effects are large. The scheme is based on a generalized Robin interface condition for the fluid pressure that includes terms involving the linear acceleration and angular acceleration of the rigid body. Added mass effects are handled in the Robin condition by inclusion of a boundary integral term that depends on the pressure. Added-damping effects due to the viscous shear forcesmore » on the body are treated by inclusion of added-damping tensors that are derived through a linearization of the integrals defining the force and torque. Added-damping effects may be important at low Reynolds number, or, for example, in the case of a rotating cylinder or rotating sphere when the rotational moments of inertia are small. In this second part of a two-part series, the general formulation of the AMP scheme is presented including the form of the AMP interface conditions and added-damping tensors for general geometries. A fully second-order accurate implementation of the AMP scheme is developed in two dimensions based on a fractional-step method for the incompressible Navier-Stokes equations using finite difference methods and overlapping grids to handle the moving geometry. Here, the numerical scheme is verified on a number of difficult benchmark problems.« less

A stable partitioned FSI algorithm for rigid bodies and incompressible flow. Part I: Model problem analysis

DOE PAGES

Banks, J. W.; Henshaw, W. D.; Schwendeman, D. W.; ...

2017-01-20

A stable partitioned algorithm is developed for fluid-structure interaction (FSI) problems involving viscous incompressible flow and rigid bodies. This added-mass partitioned (AMP) algorithm remains stable, without sub-iterations, for light and even zero mass rigid bodies when added-mass and viscous added-damping effects are large. The scheme is based on a generalized Robin interface condition for the fluid pressure that includes terms involving the linear acceleration and angular acceleration of the rigid body. Added mass effects are handled in the Robin condition by inclusion of a boundary integral term that depends on the pressure. Added-damping effects due to the viscous shear forcesmore » on the body are treated by inclusion of added-damping tensors that are derived through a linearization of the integrals defining the force and torque. Added-damping effects may be important at low Reynolds number, or, for example, in the case of a rotating cylinder or rotating sphere when the rotational moments of inertia are small. In this second part of a two-part series, the general formulation of the AMP scheme is presented including the form of the AMP interface conditions and added-damping tensors for general geometries. A fully second-order accurate implementation of the AMP scheme is developed in two dimensions based on a fractional-step method for the incompressible Navier-Stokes equations using finite difference methods and overlapping grids to handle the moving geometry. Here, the numerical scheme is verified on a number of difficult benchmark problems.« less

Socially Inclusive Development: The Foundations for Decent Societies in East and Southern Africa.

PubMed

Abbott, Pamela; Wallace, Claire; Sapsford, Roger

2017-01-01

This article is concerned with how social processes and social provision are conceptualised and measured in societies in order to offer guidance on how to improve developmental progress. Significant advances have been made in developing multidimensional measures of development, but they provide little guidance to governments on how to build sustainable societies. We argue for the need to develop a theoretically informed social and policy framework that permits the foundations for building decent societies to be put in place by governments. In our view the recently developed Decent Society Model provides such a framework. Our example is the assessment of government provision, by function, within fourteen countries of East and Southern Africa. The context is the current debates about socially inclusive development, but we argue that it is necessary to range more widely, as social processes of different kinds are multiply interrelated. Social inclusion is recognised by governments as well as international agencies, including the World Bank and the United Nations, as not only an ethical imperative but smart economics; socially inclusive societies are more stable and have greater potential for economic growth. Societies that can develop sustainably need not only to be inclusive, however, but to provide economic security for all, to be socially cohesive and to empower citizens so that as individuals and communities they can take control over their own lives.

Interior Fracture Mechanism Analysis and Fatigue Life Prediction of Surface-Hardened Gear Steel under Axial Loading.

PubMed

Li, Wei; Deng, Hailong; Liu, Pengfei

2016-10-18

The interior defect-induced fracture of surface-hardened metallic materials in the long life region has become a key issue on engineering design. In the present study, the axial loading test with fully reversed condition was performed to examine the fatigue property of a surface-carburized low alloy gear steel in the long life region. Results show that this steel represents the duplex S-N (stress-number of cycles) characteristics without conventional fatigue limit related to 10⁷ cycles. Fatigue cracks are all originated from the interior inclusions in the matrix region due to the inhabitation effect of carburized layer. The inclusion induced fracture with fisheye occurs in the short life region below 5 × 10⁵ cycles, whereas the inclusion induced fracture with fine granular area (FGA) and fisheye occurs in the long life region beyond 10⁶ cycles. The stress intensity factor range at the front of FGA can be regarded as the threshold value controlling stable growth of interior long crack. The evaluated maximum inclusion size in the effective damage volume of specimen is about 27.29 μm. Considering the size relationships between fisheye and FGA, and inclusion, the developed life prediction method involving crack growth can be acceptable on the basis of the good agreement between the predicted and experimental results.

Phenotypic variability within the inclusion body spectrum of basophilic inclusion body disease and neuronal intermediate filament inclusion disease in frontotemporal lobar degenerations with FUS-positive inclusions.

PubMed

Gelpi, Ellen; Lladó, Albert; Clarimón, Jordi; Rey, Maria Jesús; Rivera, Rosa Maria; Ezquerra, Mario; Antonell, Anna; Navarro-Otano, Judith; Ribalta, Teresa; Piñol-Ripoll, Gerard; Pérez, Anna; Valldeoriola, Francesc; Ferrer, Isidre

2012-09-01

Basophilic inclusion body disease and neuronal intermediate filament inclusion disease (NIFID) are rare diseases included among frontotemporal lobar degenerations with FUS-positive inclusions (FTLD-FUS). We report clinical and pathologic features of 2 new patients and reevaluate neuropathologic characteristics of 2 previously described cases, including an early-onset case of basophilic inclusion body disease (aged 38 years) with a 5-year disease course and abundant FUS-positive inclusion bodies and 3 NIFID cases. One NIFID case (aged 37 years) presented with early-onset psychiatric disturbances and rapidly progressive cognitive decline. Two NIFID cases had later onset (aged 64 years and 70 years) and complex neurologic deficits. Postmortem neuropathologic studies in late-onset NIFID cases disclosed α-internexin-positive "hyaline conglomerate"-type inclusions that were positive with 1 commercial anti-FUS antibody directed to residues 200 and 250, but these were negative to amino acids 90 and 220 of human FUS. Early-onset NIFID had similar inclusions that were positive with both commercial anti-FUS antibodies. Genetic testing performed on all cases revealed no FUS gene mutations. These findings indicate that phenotypic variability in NIFID, including clinical manifestations and particular neuropathologic findings, may be related to the age at onset and individual differences in the evolution of lesions.

Electrogram fractionation in murine HL-1 atrial monolayer model.

PubMed

Umapathy, Karthikeyan; Masse, Stephane; Kolodziejska, Karolina; Veenhuyzen, George D; Chauhan, Vijay S; Husain, Mansoor; Farid, Talha; Downar, Eugene; Sevaptsidis, Elias; Nanthakumar, Kumaraswamy

2008-07-01

Complex fractionated atrial electrograms have been suggested as important targets for catheter ablation of atrial fibrillation. The etiology and the mechanism of these signals have not been completely elucidated because of limitations of interpretation of these signals in relation to simultaneously acquired signals in the neighboring atrial tissue. This study sought to study the origin of electrogram fractionation under the conditions of rotor formation and wave fragmentation, using atrial monolayer preparations. We performed optical mapping of 45 atrial monolayer preparations using a complementary metal oxide semiconductor (CMOS) Brainvision Ultima camera system (SciMedia-Brainvision, Tokyo, Japan). We observed stable rotors in 32 of the 45 recordings. The derived bipolar electrograms did not show complex fractionation at the core of the rotor in any of the 32 recordings. We were also able to show that 2 bipolar electrodes placed adjacent to the core of a stable rotor in a zone where there is no wave break will record electrical activity for the majority of the rotor's cycle length. In 13 of the 45 recordings, wave break or wave collision events were present. Of these, 8 of 13 recordings showed complex fractionation. In 19 of the 27, simulation of meandering rotors also showed complex fractionation. Complex fractionated electrograms can be recorded at sites of migrating rotors and wave break. No fractionation occurs at the core of a stable rotor. Electrograms that span the rotor cycle length and alternate between 2 bipoles that straddle the core can identify site of a stable rotor.

Preparation and Characterization of Amylose Inclusion Complexes for Drug Delivery Applications.

PubMed

Carbinatto, Fernanda M; Ribeiro, Tatiana S; Colnago, Luiz Alberto; Evangelista, Raul Cesar; Cury, Beatriz S F

2016-01-01

Amylose complexes with nimesulide (NMS) and praziquantel (PZQ) were prepared by a simple and low cost method, so that high yield (>57%) and drug content (up to 68.16%) were achieved. The influence of drug:polymer ratio, temperature, and presence of palmitic acid on the complexes properties was evaluated. Differential scanning calorimetry, X-ray diffraction, and nuclear magnetic resonance data evidenced the drug-polymer interaction and the formation of inclusion complexes with semi-crystalline structures related to type II complexes. The drug release rates from complexes were lowered in acid media (pH 1.2) and phosphate buffer (pH 6.9). The presence of pancreatin promoted a significant acceleration of the release rates of both drugs, evidencing the enzymatic degradability of these complexes. The highest enzymatic resistance of PZQ1:30PA60°C complex makes the release time longer and the full release of PZQ in phosphate buffer with pancreatin occurred at 240 min, whereas the complexes with NMS and PZQ1:5PA90°C did it in 60 min. According to the Weibull model, the drug release process in media without enzyme occurred by complex mechanisms involving diffusion, swelling, and erosion. In media containing pancreatin, generally, the better correlation was with the first order, evidencing the acceleration of the release rates of drugs in the early stages of the test, due to enzymatic degradation.

Exact simulation of max-stable processes.

PubMed

Dombry, Clément; Engelke, Sebastian; Oesting, Marco

2016-06-01

Max-stable processes play an important role as models for spatial extreme events. Their complex structure as the pointwise maximum over an infinite number of random functions makes their simulation difficult. Algorithms based on finite approximations are often inexact and computationally inefficient. We present a new algorithm for exact simulation of a max-stable process at a finite number of locations. It relies on the idea of simulating only the extremal functions, that is, those functions in the construction of a max-stable process that effectively contribute to the pointwise maximum. We further generalize the algorithm by Dieker & Mikosch (2015) for Brown-Resnick processes and use it for exact simulation via the spectral measure. We study the complexity of both algorithms, prove that our new approach via extremal functions is always more efficient, and provide closed-form expressions for their implementation that cover most popular models for max-stable processes and multivariate extreme value distributions. For simulation on dense grids, an adaptive design of the extremal function algorithm is proposed.

Benzocaine complexation with p-sulfonic acid calix[n]arene: experimental ((1) H-NMR) and theoretical approaches.

PubMed

Arantes, Lucas M; Varejão, Eduardo V V; Pelizzaro-Rocha, Karin J; Cereda, Cíntia M S; de Paula, Eneida; Lourenço, Maicon P; Duarte, Hélio A; Fernandes, Sergio A

2014-05-01

The aim of this work was to study the interaction between the local anesthetic benzocaine and p-sulfonic acid calix[n]arenes using NMR and theoretical calculations and to assess the effects of complexation on cytotoxicity of benzocaine. The architectures of the complexes were proposed according to (1) H NMR data (Job plot, binding constants, and ROESY) indicating details on the insertion of benzocaine in the cavity of the calix[n]arenes. The proposed inclusion compounds were optimized using the PM3 semiempirical method, and the electronic plus nuclear repulsion energy contributions were performed at the DFT level using the PBE exchange/correlation functional and the 6-311G(d) basis set. The remarkable agreement between experimental and theoretical approaches adds support to their use in the structural characterization of the inclusion complexes. In vitro cytotoxic tests showed that complexation intensifies the intrinsic toxicity of benzocaine, possibly by increasing the water solubility of the anesthetic and favoring its partitioning inside of biomembranes. © 2013 John Wiley & Sons A/S.

Bounds on complex polarizabilities and a new perspective on scattering by a lossy inclusion

NASA Astrophysics Data System (ADS)

Milton, Graeme W.

2017-09-01

Here, we obtain explicit formulas for bounds on the complex electrical polarizability at a given frequency of an inclusion with known volume that follow directly from the quasistatic bounds of Bergman and Milton on the effective complex dielectric constant of a two-phase medium. We also describe how analogous bounds on the orientationally averaged bulk and shear polarizabilities at a given frequency can be obtained from bounds on the effective complex bulk and shear moduli of a two-phase medium obtained by Milton, Gibiansky, and Berryman, using the quasistatic variational principles of Cherkaev and Gibiansky. We also show how the polarizability problem and the acoustic scattering problem can both be reformulated in an abstract setting as "Y problems." In the acoustic scattering context, to avoid explicit introduction of the Sommerfeld radiation condition, we introduce auxiliary fields at infinity and an appropriate "constitutive law" there, which forces the Sommerfeld radiation condition to hold. As a consequence, we obtain minimization variational principles for acoustic scattering that can be used to obtain bounds on the complex backwards scattering amplitude. Some explicit elementary bounds are given.

Gallic acid/hydroxypropyl-β-cyclodextrin complex: Improving solubility for application on in vitro/ in vivo Candida albicans biofilms

PubMed Central

Teodoro, Guilherme Rodrigues; Salvador, Marcos José; Koga-Ito, Cristiane Yumi

2017-01-01

The aim of this study was to increase the solubility of gallic acid (GA) for the treatment of Candida albicans biofilm, which is very difficult to treat and requires high drug concentrations. Cyclodextrins (CDs) were used for this purpose. Complexes were evaluated by phase-solubility studies, prepared by spray drying and characterized by drug loading, scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The complexes were tested on C. albicans biofilm using in vitro and in vivo models. HPβCD formed soluble inclusion complexes with GA. The percentage of GA in GA/HPβCD was 10.8 ± 0.01%. The SEM and DSC analyses confirmed the formation of inclusion complexes. GA/HPβCD maintained the antimicrobial activity of the pure GA. GA/HPβCD was effective on C. albicans biofilms of 24 and 48h. The in vivo results showed an anti-inflammatory activity of GA/HPβCD with no difference in invading hypha counting among the groups. This study encourages the development of new antifungal agents. PMID:28700692

Sporulation of Bacillus sphaericus 2297: an electron microscope study of crystal-like inclusion biogenesis and toxicity to mosquito larvae.

PubMed

Kalfon, A; Charles, J F; Bourgouin, C; de Barjac, H

1984-04-01

Sporulation of Bacillus sphaericus strain 2297 in a synchronous liquid culture was studied by electron microscopy. The t0 of sporulation occurred 7 h after the beginning of the lag phase. Crystal-like inclusions first appeared at t2 and reached their final size between t5 and t6. The release of the spore/inclusion complex occurred at about t15 (22 h after inoculation). Toxicity against Culex pipiens larvae was related to sporulation and appeared during the early stages of sporulation. The LC50 (24 h) decreased about 10(5)-fold between t0-2 and t7, in correlation with the formation of crystalline inclusions. Heat resistance of spores appeared later than toxicity.

Fault tolerance in protein interaction networks: stable bipartite subgraphs and redundant pathways.

PubMed

Brady, Arthur; Maxwell, Kyle; Daniels, Noah; Cowen, Lenore J

2009-01-01

As increasing amounts of high-throughput data for the yeast interactome become available, more system-wide properties are uncovered. One interesting question concerns the fault tolerance of protein interaction networks: whether there exist alternative pathways that can perform some required function if a gene essential to the main mechanism is defective, absent or suppressed. A signature pattern for redundant pathways is the BPM (between-pathway model) motif, introduced by Kelley and Ideker. Past methods proposed to search the yeast interactome for BPM motifs have had several important limitations. First, they have been driven heuristically by local greedy searches, which can lead to the inclusion of extra genes that may not belong in the motif; second, they have been validated solely by functional coherence of the putative pathways using GO enrichment, making it difficult to evaluate putative BPMs in the absence of already known biological annotation. We introduce stable bipartite subgraphs, and show they form a clean and efficient way of generating meaningful BPMs which naturally discard extra genes included by local greedy methods. We show by GO enrichment measures that our BPM set outperforms previous work, covering more known complexes and functional pathways. Perhaps most importantly, since our BPMs are initially generated by examining the genetic-interaction network only, the location of edges in the protein-protein physical interaction network can then be used to statistically validate each candidate BPM, even with sparse GO annotation (or none at all). We uncover some interesting biological examples of previously unknown putative redundant pathways in such areas as vesicle-mediated transport and DNA repair.

Fault Tolerance in Protein Interaction Networks: Stable Bipartite Subgraphs and Redundant Pathways

PubMed Central

Brady, Arthur; Maxwell, Kyle; Daniels, Noah; Cowen, Lenore J.

2009-01-01

As increasing amounts of high-throughput data for the yeast interactome become available, more system-wide properties are uncovered. One interesting question concerns the fault tolerance of protein interaction networks: whether there exist alternative pathways that can perform some required function if a gene essential to the main mechanism is defective, absent or suppressed. A signature pattern for redundant pathways is the BPM (between-pathway model) motif, introduced by Kelley and Ideker. Past methods proposed to search the yeast interactome for BPM motifs have had several important limitations. First, they have been driven heuristically by local greedy searches, which can lead to the inclusion of extra genes that may not belong in the motif; second, they have been validated solely by functional coherence of the putative pathways using GO enrichment, making it difficult to evaluate putative BPMs in the absence of already known biological annotation. We introduce stable bipartite subgraphs, and show they form a clean and efficient way of generating meaningful BPMs which naturally discard extra genes included by local greedy methods. We show by GO enrichment measures that our BPM set outperforms previous work, covering more known complexes and functional pathways. Perhaps most importantly, since our BPMs are initially generated by examining the genetic-interaction network only, the location of edges in the protein-protein physical interaction network can then be used to statistically validate each candidate BPM, even with sparse GO annotation (or none at all). We uncover some interesting biological examples of previously unknown putative redundant pathways in such areas as vesicle-mediated transport and DNA repair. PMID:19399174

Carbonate Mineral Assemblages as Inclusions in Yakutian Diamonds: TEM Verifications

NASA Astrophysics Data System (ADS)

Logvinova, A. M.; Wirth, R.; Sobolev, N. V.; Taylor, L. A.

2014-12-01

Carbonate mineral inclusions are quite rare in diamonds from the upper mantle, but are evidence for a carbonate abundance in the mantle. It is believed that such carbonatitic inclusions originated from high-density fluids (HDFs) that were enclosed in diamond during its growth. Using TEM and EPMA, several kinds of carbonate inclusions have been identified in Yakutian diamonds : aragonite, dolomite, magnesite, Ba-, Sr-, and Fe-rich carbonates. Most of them are represented by multi-phase inclusions of various chemically distinct carbonates, rich in Ca, Mg, and K and associated with minor amounts of silicate, oxide, saline, and volatile phases. Volatiles, leaving some porosity, played a significant role in the diamond growth. A single crystal of aragonite (60μm) is herein reported for the first time. This inclusion is located in the center of a diamond from the Komsomolskaya pipe. Careful CL imaging reveals the total absence of cracks around the aragonite inclusion - i.e., closed system. This inclusion has been identified by X-ray diffraction and microprobe analysis. At temperatures above 1000 0C, aragonite is only stable at high pressures of 5-6 GPa. Inside this aragonite, we observed nanocrystalline inclusions of titanite, Ni-rich sulfide, magnetite, water-bearing Mg-silicate, and fluid bubbles. Dolomite is common in carbonate multi-phase inclusions in diamonds from the Internatsionalnaya, Yubileinaya, and Udachnaya kimberlite pipes. Alluvial diamonds of the northeastern Siberian Platform are divided into two groups based on the composition of HDFs: 1) Mg-rich multi-phase inclusions (60% magnesite + dolomite + Fe-spinel + Ti-silicate + fluid bubbles); and 2) Ca-rich multi-phase inclusions (Ca,Ba-, Ca,Sr-, Ca,Fe-carbonates + Ti-silicate + Ba-apatite + fluid bubbles). High-density fluids also contain K. Volatiles in the fluid bubbles are represented by water, Cl, F, S, CO2, CH4, and heavy hydrocarbons. Origin of the second group of HDFs may be related to the non-silicate carbonatitic melt. We consider the primary hydrous, Сa-rich and Mg-poor carbonate melts as having formed in subducted oceanic crust. Variations of carbonate-inclusion compositions among diamonds indicate the variability in the source media during the formation of diamond and may be the result of metasomatic interaction with host rocks.

Persons with Epilepsy: Between Social Inclusion and Marginalisation

PubMed Central

Mlinar, Simona; Petek, Davorina; Cotič, Živa; Mencin Čeplak, Metka; Zaletel, Marjan

2016-01-01

Background. Epilepsy is a chronic neurological disorder that can lead to complex psychosocial consequences. Epilepsy can change the social status of persons with epilepsy (PWE) and has an effect on their social inclusion as well as their perception of social inclusion. This study aims to explore subjective experiences with social inclusion of PWE in Slovenia. Methods. This study takes a qualitative approach. Eleven semistructured interviews were conducted with eleven participants. Interviews were analysed using thematic analysis. Results. Epilepsy has physical, emotional, and social consequences. Physical consequences of epilepsy are mainly tiredness and exhaustion following an epileptic episode, frequently accompanied by headaches. Emotional consequences are different forms of fear. The main social consequence identified is a negative effect on PWE's social network, which leads to (self-)isolation and social distrust. Conclusion. PWE experience of social inclusion depends on various psychosocial factors and differs from person to person. The consequences of epilepsy are shown in PWE social contacts and their sense of social inclusion and autonomy. PMID:27212802

Persons with Epilepsy: Between Social Inclusion and Marginalisation.

PubMed

Mlinar, Simona; Petek, Davorina; Cotič, Živa; Mencin Čeplak, Metka; Zaletel, Marjan

2016-01-01

Epilepsy is a chronic neurological disorder that can lead to complex psychosocial consequences. Epilepsy can change the social status of persons with epilepsy (PWE) and has an effect on their social inclusion as well as their perception of social inclusion. This study aims to explore subjective experiences with social inclusion of PWE in Slovenia. This study takes a qualitative approach. Eleven semistructured interviews were conducted with eleven participants. Interviews were analysed using thematic analysis. Epilepsy has physical, emotional, and social consequences. Physical consequences of epilepsy are mainly tiredness and exhaustion following an epileptic episode, frequently accompanied by headaches. Emotional consequences are different forms of fear. The main social consequence identified is a negative effect on PWE's social network, which leads to (self-)isolation and social distrust. PWE experience of social inclusion depends on various psychosocial factors and differs from person to person. The consequences of epilepsy are shown in PWE social contacts and their sense of social inclusion and autonomy.

A Cognitive Complexity Metric Applied to Cognitive Development

ERIC Educational Resources Information Center

Andrews, Glenda; Halford, Graeme S.

2002-01-01

Two experiments tested predictions from a theory in which processing load depends on relational complexity (RC), the number of variables related in a single decision. Tasks from six domains (transitivity, hierarchical classification, class inclusion, cardinality, relative-clause sentence comprehension, and hypothesis testing) were administered to…

Quantum chemical density functional theory studies on the molecular structure and vibrational spectra of Gallic acid imprinted polymers

NASA Astrophysics Data System (ADS)

Pardeshi, Sushma; Dhodapkar, Rita; Kumar, Anupama

2013-12-01

Gallic acid (GA) is known by its antioxidant, anticarcinogenic properties and scavenger activity against several types of harmful free radicals. Molecularly imprinted polymers (MIPs) are used in separation of a pure compound from complex matrices. A stable template-monomer complex generates the MIPs with the highest affinity and selectivity for the template. The quantum chemical computations based on density functional theory (DFT) was used on the template Gallic acid (GA), monomer acrylic acid (AA) and GA-AA complex to study the nature of interactions involved in the GA-AA complex. B3LYP/6-31+G(2d,2p) model chemistry was used to optimize their structures and frequency calculations. The effect of porogen acetonitrile (ACN) on complex formation was included by using polarizable continuum model (PCM). The results demonstrated the formation of a stable GA-AA complex through the intermolecular hydrogen bonding between carboxylic acid groups of GA and AA. The Mulliken atomic charge analysis and simulated vibrational spectra also supported the stable hydrogen bonding interaction between the carboxylic acid groups of GA and AA with minimal interference of porogen ACN. Further, simulations on GA-AA mole ratio revealed that 1:4 GA-AA was optimum for synthesis of MIP for GA.

Single and multiphase inclusions in metapelitic garnets of the Rhodope Metamorphic Province, NE Greece.

PubMed

Mposkos, Evripidis; Perraki, Maria; Palikari, Sarra

2009-08-01

Single and multiphase inclusions in garnet porphyroblasts from the diamond-bearing pelitic gneisses were studied by means of combined Raman Spectroscopy and Electron Scanning Microscopy (SEM/EDX). They are either randomly distributed or with preferred orientation within the garnet host and their dimensions vary from less than 5 up to 60 microm. In the single-phase inclusions quartz, rutile, kyanite and graphite dominate. Biotite, zircon, apatite, monazite and allanite are also common. Two types of multiphase inclusions were recognized, hydrous silicate (Type I) and silicate-carbonate (Type II) ones. The carbon-bearing multiphase inclusions predominantly consist of Mg-siderite+graphite+CO(2)+muscovite+quartz formed by a high density carboniferous fluid rich in Fe, Mg, Si and less Ca, Mn, Al and K trapped in the growing garnet in a prograde stage of metamorphism at high-pressure (HP) conditions. The carbon-free multiphase inclusions predominantly consist of biotite+quartz+rutile+/-kyanite+muscovite formed through decompression-dehydration/melting reactions of pre-existing phengite. Single and multiphase inclusions are characterized by polygonal to negative crystal shape formed by dissolution-reprecipitation mechanism between the garnet host and the inclusions during the long lasting cooling period (>100 Ma) of the Kimi Complex.

Evolution of Oxide Inclusions in Si-Mn Killed Steels During Hot-Rolling Process

NASA Astrophysics Data System (ADS)

Yang, Wen; Guo, Changbo; Zhang, Lifeng; Ling, Haitao; Li, Chao

2017-10-01

The evolution of oxide inclusions in Si-Mn killed steels refined by slags of different basicity during a four-pass industrial hot-rolling process was investigated using an automated microscopy system. High-basicity refining slag induced the formation of CaO- and Al2O3-containing inclusions, while refining slag with 0.8 basicity induced dominant inclusions of SiO2 and MnO-SiO2. CaO-SiO2-Al2O3 inclusions mainly formed endogenously during solidification and cooling of Ca-containing steels, where Ca originated from slag-steel reactions. However, the larger-sized higher-CaO inclusions originated from slag entrainment. Different inclusions presented different hot-rolling behaviors. The inclusion composition changed by deformation and new phase formation. The dominant oxide types were unchanged under refinement by low-basicity slag; however, they changed under refinement with high-basicity slag. The deformation index of inclusions decreased with increasing accumulated reduction (AR) of the steel. The difference in deformation index between different inclusion types was the largest in the first rolling stage and decreased in subsequent stages. SiO2-CaO and SiO2-MnO-CaO inclusions had larger deformation indices during hot rolling but smaller indices in the last two stages. High-basicity slag increased inclusion complexity; from the perspective of cold-drawing performance, low-basicity refining slag is better for the industrial production of tire-cord steels.

External micro-PIXE analysis of fluid inclusions: Test of the LABEC facility on samples of quartz veins from Apuan Alps (Italy)

NASA Astrophysics Data System (ADS)

Massi, M.; Calusi, S.; Giuntini, L.; Ruggieri, G.; Dini, A.

2008-05-01

Fluid inclusions are small portions, usually smaller than 100 μm, of fluid trapped within minerals during or after growth. Their characteristics provide therefore fundamental information on nature and evolution of fluids present in the past in different geological environments. At the LABEC laboratory in Firenze, high-salinity fluid inclusions in quartz crystals, coming from the Apuan Alps metamorphic complex, were analysed at the external scanning microbeam. Results, although still preliminary, have already provided us with hints on fluid-rock interaction processes during the metamorphism of the Apuan Alps.

Characterization of aspartame-cyclodextrin complexation.

PubMed

Sohajda, Tamás; Béni, Szabolcs; Varga, Erzsébet; Iványi, Róbert; Rácz, Akos; Szente, Lajos; Noszál, Béla

2009-12-05

The inclusion complex formation of aspartame (guest) and various cyclodextrins (host) were examined using 1H NMR titration and capillary electrophoresis. Initially the protonation constants of aspartame were determined by NMR-pH titration with in situ pH measurement to yield log K1=7.83 and log K2=2.96. Based on these values the stability of the complexes formed by aspartame and 21 different cyclodextrins (CDs) were studied at pH 2.5, pH 5.2 and pH 9.0 values where aspartame exists predominantly in monocationic, zwitterionic and monoanionic form, respectively. The host cyclodextrin derivatives differed in various sidechains, degree of substitution, charge and purity so that the effect of these properties could be examined systematically. Concerning size, the seven-membered beta-cyclodextrin and its derivatives have been found to be the most suitable host molecules for complexation. Highest stability was observed for the acetylated derivative with a degree of substitution of 7. The purity of the CD enhanced the complexation while the degree of substitution did not provide obvious consequences. Finally, geometric aspects of the inclusion complex were assessed by 2D ROESY NMR and molecular modelling which proved that the guest's aromatic ring enters the wider end of the host cavity.

Assessment of Stone Complexity for PCNL: A Systematic Review of the Literature, How Best Can We Record Stone Complexity in PCNL?

PubMed

Withington, John; Armitage, James; Finch, William; Wiseman, Oliver; Glass, Jonathan; Burgess, Neil

2016-01-01

This study aims to systematically review the literature reporting tools for scoring stone complexity and the stratification of outcomes by stone complexity. In doing so, we aim to determine whether the evidence favors uniform adoption of any one scoring system. PubMed and Embase databases were systematically searched for relevant studies from 2004 to 2014. Reports selected according to predetermined inclusion and exclusion criteria were appraised in terms of methodologic quality and their findings summarized in structured tables. After review, 15 studies were considered suitable for inclusion. Four distinct scoring systems were identified and a further five studies that aimed to validate aspects of those scoring systems. Six studies reported the stratification of outcomes by stone complexity, without specifically defining a scoring system. All studies reported some correlation between stone complexity and stone clearance. Correlation with complications was less clearly established, where investigated. This review does not allow us to firmly recommend one scoring system over the other. However, the quality of evidence supporting validation of the Guy's Stone Score is marginally superior, according to the criteria applied in this study. Further evaluation of the interobserver reliability of this scoring system is required.

The influence of the preparation methods on the inclusion of model drugs in a beta-cyclodextrin cavity.

PubMed

Salústio, P J; Feio, G; Figueirinhas, J L; Pinto, J F; Cabral Marques, H M

2009-02-01

The work aims to prove the complexation of two model drugs (ibuprofen, IB and indomethacin, IN) by beta-cyclodextrin (betaCD), and the effect of water in such a process, and makes a comparison of their complexation yields. Two methods were considered: kneading of a binary mixture of the drug, betaCD, and inclusion of either IB or IN in aqueous solutions of betaCD. In the latter method water was removed by air stream, spray-drying and freeze-drying. To prove the formation of complexes in final products, optical microscopy, UV spectroscopy, IR spectroscopy, DSC, X-ray and NMR were considered. Each powder was added to an acidic solution (pH=2) to quantify the concentration of the drug inside betaCD cavity. Other media (pH=5 and 7) were used to prove the existence of drug not complexed in each powder, as the drugs solubility increases with the pH. It was observed that complexation occurred in all powders, and that the fraction of drug inside the betaCD did not depend neither on the method of complexation nor on the processes of drying considered.

A petrologic and ion microprobe study of a Vigarano Type B refractory inclusion - Evolution by multiple stages of alteration and melting

NASA Technical Reports Server (NTRS)

Macpherson, Glenn J.; Davis, Andrew M.

1993-01-01

A Type B Ca-, Al-rich 6-m-diam inclusion (CAI) found in the Vigarano C3V chondrite was inspected using optical and scanning electron microscopies and ion microprobe analyses. It was found that the primary constituents of the CAI inclusion are (in percent), melilite (52), fassaite, (20), anorthite (18), spinel (10), and trace Fe-Ni metal. It is noted that, while many of the properties of the inclusion indicate solidification from a melt droplet, the Al-26/Mg-26 isotopic systematics and some textural relationships are incompatible with single-stage closed system crystallization of a homogeneous molten droplet, indicating that the history of this inclusion must have been more complex than melt solidification alone. Moreover, there was unusually high content of Na in melilite, suggesting that the droplet did not form by melting of pristine high-temperature nebular condensates.

Corundum-Hibonite Inclusions and the Environments of High Temperature Processing in the Early Solar System

NASA Technical Reports Server (NTRS)

Needham, A. W.; Messenger, S.

2013-01-01

Calcium, Aluminum-rich inclusions (CAIs) are composed of the suite of minerals predicted to be the first to condense from a cooling gas of solar composition [1]. Yet, the first phase to condense, corundum, is rare in CAIs, having mostly reacted to form hibonite followed by other phases at lower temperatures. Many CAIs show evidence of complex post-formational histories, including condensation, evaporation, and melting [e.g. 2, 3]. However, the nature of these thermal events and the nebular environments in which they took place are poorly constrained. Some corundum and corundum-hibonite grains appear to have survived or avoided these complex CAI reprocessing events. Such ultra-refractory CAIs may provide a clearer record of the O isotopic composition of the Sun and the evolution of the O isotopic composition of the planet-forming region [4-6]. Here we present in situ O and Mg isotopic analyses of two corundum/hibonite inclusions that record differing formation histories.

Septins arrange F-actin-containing fibers on the Chlamydia trachomatis inclusion and are required for normal release of the inclusion by extrusion.

PubMed

Volceanov, Larisa; Herbst, Katharina; Biniossek, Martin; Schilling, Oliver; Haller, Dirk; Nölke, Thilo; Subbarayal, Prema; Rudel, Thomas; Zieger, Barbara; Häcker, Georg

2014-10-07

Chlamydia trachomatis is an obligate intracellular human pathogen that grows inside a membranous, cytosolic vacuole termed an inclusion. Septins are a group of 13 GTP-binding proteins that assemble into oligomeric complexes and that can form higher-order filaments. We report here that the septins SEPT2, -9, -11, and probably -7 form fibrillar structures around the chlamydial inclusion. Colocalization studies suggest that these septins combine with F actin into fibers that encase the inclusion. Targeting the expression of individual septins by RNA interference (RNAi) prevented the formation of septin fibers as well as the recruitment of actin to the inclusion. At the end of the developmental cycle of C. trachomatis, newly formed, infectious elementary bodies are released, and this release occurs at least in part through the organized extrusion of intact inclusions. RNAi against SEPT9 or against the combination of SEPT2/7/9 substantially reduced the number of extrusions from a culture of infected HeLa cells. The data suggest that a higher-order structure of four septins is involved in the recruitment or stabilization of the actin coat around the chlamydial inclusion and that this actin recruitment by septins is instrumental for the coordinated egress of C. trachomatis from human cells. The organization of F actin around parasite-containing vacuoles may be a broader response mechanism of mammalian cells to the infection by intracellular, vacuole-dwelling pathogens. Importance: Chlamydia trachomatis is a frequent bacterial pathogen throughout the world, causing mostly eye and genital infections. C. trachomatis can develop only inside host cells; it multiplies inside a membranous vacuole in the cytosol, termed an inclusion. The inclusion is covered by cytoskeletal "coats" or "cages," whose organization and function are poorly understood. We here report that a relatively little-characterized group of proteins, septins, is required to organize actin fibers on the inclusion and probably through actin the release of the inclusion. Septins are a group of GTP-binding proteins that can organize into heteromeric complexes and then into large filaments. Septins have previously been found to be involved in the interaction of the cell with bacteria in the cytosol. Our observation that they also organize a reaction to bacteria living in vacuoles suggests that they have a function in the recognition of foreign compartments by a parasitized human cell. Copyright © 2014 Volceanov et al.

Effect of guest drug character encapsulated in the cavity and intermolecular spaces of γ-cyclodextrins on the dissolution property of ternary γ-cyclodextrin complex.

PubMed

Liu, Nan; Higashi, Kenjirou; Ueda, Keisuke; Moribe, Kunikazu

2017-10-15

Various ternary Guest 2/(Guest 1/γ-cyclodextrin (CD)) complexes were prepared using a cogrinding and subsequent heating method, wherein Guest 1 was incorporated in the cavity of γ-CD and Guest 2 was incorporated into the intermolecular spaces between γ-CD columns. Dissolution fluxes of Guest 1 and Guest 2 from all ternary complexes were almost identical. The dissolution flux of flurbiprofen (Guest 1) from the ternary complexes depended on the solubility of Guest 2 drugs (naproxen

Improved natural rubber composites reinforced with a complex filler network of biobased nanoparticles and ionomer

USDA-ARS?s Scientific Manuscript database

Biobased rubber composites are renewable and sustainable. Significant improvement in modulus of rubber composite reinforced with hydrophilic filler was achieved with the inclusion of ionomers. Soy particles aided with ionomer, carboxylated styrene-butadiene (CSB), formed a strong complex filler netw...

Amoebal endosymbiont Parachlamydia acanthamoebae Bn9 can grow in immortal human epithelial HEp-2 cells at low temperature; an in vitro model system to study chlamydial evolution.

PubMed

Yamane, Chikayo; Yamazaki, Tomohiro; Nakamura, Shinji; Matsuo, Junji; Ishida, Kasumi; Yamazaki, Sumire; Oguri, Satoshi; Shouji, Natsumi; Hayashi, Yasuhiro; Yoshida, Mitsutaka; Yimin; Yamaguchi, Hiroyuki

2015-01-01

Ancient chlamydiae diverged into pathogenic and environmental chlamydiae 0.7-1.4 billion years ago. However, how pathogenic chlamydiae adapted to mammalian cells that provide a stable niche at approximately 37 °C, remains unknown, although environmental chlamydiae have evolved as endosymbionts of lower eukaryotes in harsh niches of relatively low temperatures. Hence, we assessed whether an environmental chlamydia, Parachlamydia Bn9, could grow in human HEp-2 cells at a low culture temperature of 30 °C. The assessment of inclusion formation by quantitative RT-PCR revealed that the numbers of bacterial inclusion bodies and the transcription level of 16SrRNA significantly increased after culture at 30 °C compared to at 37 °C. Confocal microscopy showed that the bacteria were located close to HEp-2 nuclei and were actively replicative. Transmission electron microscopy also revealed replicating bacteria consisting of reticular bodies, but with a few elementary bodies. Cytochalasin D and rifampicin inhibited inclusion formation. Lactacystin slightly inhibited bacterial inclusion formation. KEGG analysis using a draft genome sequence of the bacteria revealed that it possesses metabolic pathways almost identical to those of pathogenic chlamydia. Interestingly, comparative genomic analysis with pathogenic chlamydia revealed that the Parachlamydia similarly possess the genes encoding Type III secretion system, but lacking genes encoding inclusion membrane proteins (IncA to G) required for inclusion maturation. Taken together, we conclude that ancient chlamydiae had the potential to grow in human cells, but overcoming the thermal gap was a critical event for chlamydial adaptation to human cells.

Weak convergence to isotropic complex [Formula: see text] random measure.

PubMed

Wang, Jun; Li, Yunmeng; Sang, Liheng

2017-01-01

In this paper, we prove that an isotropic complex symmetric α -stable random measure ([Formula: see text]) can be approximated by a complex process constructed by integrals based on the Poisson process with random intensity.

Structural investigation of the β-cyclodextrin complexes with chiral bicyclic monoterpenes - Influence of the functionality group on the host-guest stoichiometry

NASA Astrophysics Data System (ADS)

Ceborska, Magdalena

2017-10-01

The crystal structures of the complexes of β-cyclodextrin with (+)- and (-)-camphors are presented. The comparison of the obtained crystal structures with available data for other complexes of β-cyclodextrin with chiral bicyclic monoterpenes (hydrocarbon (+)-fenchene and alcohols: (-)-isopinocampheol, and (+)-, and (-)-borneols) obtained from Cambridge Structural Database (CSD) shows the trend of alcohols to form dimeric complexes of 2:3 stoichiometry, while hydrocarbons and ketones prefer to form 2:2 host-guest inclusion complexes.

High-level ab initio studies of NO(X2Π)-O2(X3Σg -) van der Waals complexes in quartet states

NASA Astrophysics Data System (ADS)

Grein, Friedrich

2018-05-01

Geometry optimisations were performed on nine different structures of NO(X2Π)-O2(X3Σg-) van der Waals complexes in their quartet states, using the explicitly correlated RCCSD(T)-F12b method with basis sets up to the cc-pVQZ-F12 level. For the most stable configurations, counterpoise-corrected optimisations as well as extrapolations to the complete basis set (CBS) were performed. The X structure in the 4A‧ state was found to be most stable, with a CBS binding energy of -157 cm-1. The slipped tilted structures with N closer to O2 (Slipt-N), as well as the slipped parallel structure with O of NO closer to O2 (Slipp-O) in 4A″ states have binding energies of about -130 cm-1. C2v and linear complexes are less stable. According to calculated harmonic frequencies, the X isomer is bound. Isotropic hyperfine coupling constants of the complex are compared with those of the monomers.

Theoretical Study of Oxovanadium(IV) Complexation with Formamidoximate: Implications for the Design of Uranyl-Selective Adsorbents

DOE PAGES

Mehio, Nada; Ivanov, Alexander S.; Ladshaw, Austin P.; ...

2015-11-22

Poly(acrylamidoxime) fibers are the current state of the art adsorbent for mining uranium from seawater. However, the competition between uranyl (UO 2 2+) and vanadium ions poses a challenge to mining on the industrial scale. In this work, we employ density functional theory (DFT) and coupled-cluster methods (CCSD(T)) in the restricted formalism to investigate potential binding motifs of the oxovanadium(IV) ion (VO 2+) with the formamidoximate ligand. Consistent with experimental EXAFS data, the hydrated six-coordinate complex is predicted to be preferred over the hydrated five-coordinate complex. Here, our investigation of formamidoximate-VO 2+ complexes universally identified the most stable binding motifmore » formed by chelating a tautomerically rearranged imino hydroxylamine via the imino nitrogen and hydroxylamine oxygen. The alternative binding motifs for amidoxime chelation via a non-rearranged tautomer and 2 coordination are found to be ~11 kcal/mol less stable. Ultimately, the difference in the most stable VO 2+ and UO 2 2+ binding conformation has important implications for the design of more selective UO 2 2+ ligands.« less

Magnitude and nature of carbohydrate-aromatic interactions in fucose-phenol and fucose-indole complexes: CCSD(T) level interaction energy calculations.

PubMed

Tsuzuki, Seiji; Uchimaru, Tadafumi; Mikami, Masuhiro

2011-10-20

The CH/π contact structures of the fucose-phenol and fucose-indole complexes and the stabilization energies by formation of the complexes (E(form)) were studied by ab initio molecular orbital calculations. The three types of interactions (CH/π and OH/π interactions and OH/O hydrogen bonds) were compared and evaluated in a single molecular system and at the same level of theory. The E(form) calculated for the most stable CH/π contact structure of the fucose-phenol complex at the CCSD(T) level (-4.9 kcal/mol) is close to that for the most stable CH/π contact structure of the fucose-benzene complex (-4.5 kcal/mol). On the other hand the most stable CH/π contact structure of the fucose-indole complex has substantially larger E(form) (-6.5 kcal/mol). The dispersion interaction is the major source of the attraction in the CH/π contact structures of the fucose-phenol and fucose-indole complexes as in the case of the fucose-benzene complex. The electrostatic interactions in the CH/π contact structures are small (less than 1.5 kcal/mol). The nature of the interactions between the nonpolar surface of the carbohydrate and aromatic rings is completely different from that of the conventional hydrogen bonds where the electrostatic interaction is the major source of the attraction. The distributed multipole analysis and DFT-SATP analysis show that the dispersion interactions in the CH/π contact structure of fucose-indole complex are substantially larger than those in the CH/π contact structures of fucose-benzene and fucose-phenol complexes. The large dispersion interactions are responsible for the large E(form) for the fucose-indole complex.

Interactions between HIV-1 Reverse Transcriptase and the Downstream Template Strand in Stable Complexes with Primer-Template

PubMed Central

Rutvisuttinunt, Wiriya; Meyer, Peter R.; Scott, Walter A.

2008-01-01

Background Human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT) forms stable ternary complexes in which RT is bound tightly at fixed positions on the primer-template (P/T). We have probed downstream interactions between RT and the template strand in the complex containing the incoming dNTP (+1 dNTP•RT•P/T complex) and in the complex containing the pyrophosphate analog, foscarnet (foscarnet•RT•P/T complex). Methods and Results UV-induced cross-linking between RT and the DNA template strand was most efficient when a bromodeoxyuridine residue was placed in the +2 position (the first template position downstream from the incoming dNTP). Furthermore, formation of the +1 dNTP•RT•P/T complex on a biotin-containing template inhibited binding of streptavidin when biotin was in the +2 position on the template but not when the biotin was in the +3 position. Streptavidin pre-bound to a biotin residue in the template caused RT to stall two to three nucleotides upstream from the biotin residue. The downstream border of the complex formed by the stalled RT was mapped by digestion with exonuclease RecJF. UV-induced cross-linking of the complex formed by the pyrophosphate analog, foscarnet, with RT and P/T occurred preferentially with bromodeoxyuridine in the +1 position on the template in keeping with the location of RT one base upstream in the foscarnet•RT•P/T complex (i.e., in the pre-translocation position). Conclusions For +1 dNTP•RT•P/T and foscarnet•RT•P/T stable complexes, tight interactions were observed between RT and the first unpaired template nucleotide following the bound dNTP or the primer terminus, respectively. PMID:18974785

Hydrothermal dolomitization of the Bekhme formation (Upper Cretaceous), Zagros Basin, Kurdistan Region of Iraq: Record of oil migration and degradation

NASA Astrophysics Data System (ADS)

Mansurbeg, Howri; Morad, Daniel; Othman, Rushdy; Morad, Sadoon; Ceriani, Andrea; Al-Aasm, Ihsan; Kolo, Kamal; Spirov, Pavel; Proust, Jean Noel; Preat, Alain; Koyi, Hemin

2016-07-01

The common presence of oil seepages in dolostones is widespread in Cretaceous carbonate successions of the Kurdistan Region of Iraq. This integrated field, petrographic, chemical, stable C, O and Sr isotopes, and fluid inclusion study aims to link dolomitization to the origin and geochemical evolution of fluids and oil migration in the Upper Cretaceous Bekhme carbonates. Flux of hot basinal (hydrothermal) brines, which is suggested to have occurred during the Zagros Orogeny, resulted in dolomitization and cementation of vugs and fractures by coarse-crystalline saddle dolomite, equant calcite and anhydrite. The saddle dolomite and host dolostones have similar stable isotopic composition and formed prior to oil migration from hot (81-115 °C) basinal NaCl-MgCl2-H2O brines with salinities of 18-22 wt.% NaCl eq. The equant calcite cement, which surrounds and hence postdates saddle dolomite, has precipitated during oil migration from cooler (60-110 °C) NaCl-CaCl2-H2O brines (14-18 wt.% NaCl eq). The yellowish fluorescence color of oil inclusions in the equant calcite indicates that the oil had API gravity of 15-25° composition, which is lighter than present-day oil in the reservoirs (API of 10-17°). This difference in oil composition is attributed to oil degradation by the flux of meteoric water, which is evidenced by the low δ13C values (- 8.5‰ to - 3.9‰ VPDB) as well as by nil salinity and low temperature in fluid inclusions of late columnar calcite cement. This study demonstrates that linking fluid flux history and related diagenesis to the tectonic evolution of the basin provides important clues to the timing of oil migration, degradation and reservoir evolution.

Microwave gallium-68 radiochemistry for kinetically stable bis(thiosemicarbazone) complexes: structural investigations and cellular uptake under hypoxia.

PubMed

Alam, Israt S; Arrowsmith, Rory L; Cortezon-Tamarit, Fernando; Twyman, Frazer; Kociok-Köhn, Gabriele; Botchway, Stanley W; Dilworth, Jonathan R; Carroll, Laurence; Aboagye, Eric O; Pascu, Sofia I

2016-01-07

We report the microwave synthesis of several bis(thiosemicarbazones) and the rapid gallium-68 incorporation to give the corresponding metal complexes. These proved kinetically stable under 'cold' and 'hot' biological assays and were investigated using laser scanning confocal microscopy, flow cytometry and radioactive cell retention studies under normoxia and hypoxia. (68)Ga complex retention was found to be 34% higher in hypoxic cells than in normoxic cells over 30 min, further increasing to 53% at 120 min. Our data suggests that this class of gallium complexes show hypoxia selectivity suitable for imaging in living cells and in vivo tests by microPET in nude athymic mice showed that they are excreted within 1 h of their administration.

Chaotification of complex networks with impulsive control.

PubMed

Guan, Zhi-Hong; Liu, Feng; Li, Juan; Wang, Yan-Wu

2012-06-01

This paper investigates the chaotification problem of complex dynamical networks (CDN) with impulsive control. Both the discrete and continuous cases are studied. The method is presented to drive all states of every node in CDN to chaos. The proposed impulsive control strategy is effective for both the originally stable and unstable CDN. The upper bound of the impulse intervals for originally stable networks is derived. Finally, the effectiveness of the theoretical results is verified by numerical examples.

Complex symmetric matrices with strongly stable iterates

NASA Technical Reports Server (NTRS)

Tadmor, E.

1985-01-01

Complex-valued symmetric matrices are studied. A simple expression for the spectral norm of such matrices is obtained, by utilizing a unitarily congruent invariant form. A sharp criterion is provided for identifying those symmetric matrices whose spectral norm is not exceeding one: such strongly stable matrices are usually sought in connection with convergent difference approximations to partial differential equations. As an example, the derived criterion is applied to conclude the strong stability of a Lax-Wendroff scheme.

Modification of Alumina and Spinel Inclusions by Calcium in Liquid Steel

NASA Astrophysics Data System (ADS)

Verma, Neerav

2011-12-01

Steel Cleanliness plays a crucial role in determining steel properties such as toughness, ductility, formability, corrosion resistance and surface quality. The production of clean steel often involves the elimination or chemical and morphological modification of oxide and sulfide inclusions. Along with deteriorating the steel properties, solid inclusions can affect steel castability through nozzle clogging. Nozzle clogging occurs when solid inclusions accumulate in the caster pouring system such as the ladle shroud or submerged entry nozzle (SEN). Thus, it is important to understand how to achieve desired inclusion characteristics (shape, size and chemistry) through the steelmaking process. Among the various practices adopted in industries to counteract the effect of solid inclusions, modification of solid inclusions to liquid or partially liquid state through calcium treatment is one of the methods. Calcium can be used because it has a strong ability to form oxides and sulfides. In Al-killed steels, the most common inclusions are alumina (Al2O3) inclusions, which are solid at steelmaking temperatures. On calcium treatment, solid alumina inclusions are converted to calcium aluminates, which have liquidus temperatures lower than steelmaking temperature (1600°C) [14]. It has been found that alumina inclusions may contain some MgO and such inclusions are termed alumina magnesia spinels (Al2O3.xMgO) [18]. These spinels are more stable than alumina and it has been suggested that they might be more difficult to modify [18]. But, some authors have proposed that MgO can actually help in the liquefaction of inclusions, and have demonstrated successful modification of spinels by Ca treatment [20, 21]. In the present research, the mechanism of transformation of alumina and spinel inclusions upon calcium treatment was studied by characterizing transient evolution of inclusions. A vacuum induction was used for melting, making additions (Al, Al-Mg and CaSi2) and sampling. The samples were characterized for inclusion shape, size and chemistry through scanning electron microscopy (SEM). Automated inclusion analysis tools (like ASCAT [59, 91, 92], INCA-GSR [126]; Please refer section 6.4., page number 68) were employed to generate statistical information of the inclusions. Thermodynamic database software FACTSAGE [62] was used to determine thermochemistry of reactions, ternary phase diagrams (Ca-Al-S and Ca-Al-Mg systems). The compositions of the inclusions were tracked before and after calcium treatment to determine the effectiveness of calcium treatment. Extraction of inclusions through dissolution of iron in bromine-methanol solution was employed to reveal 3-D geometry of inclusions and analyze inclusions through EDS (Energy-dispersive X-ray spectroscopy) without any matrix effects. Various industrial samples were also analyzed to confirm the feasibility of various reaction mechanisms deduced through experiments. Successful modification of alumina and spinel inclusions by calcium was demonstrated [85, 86]. It was observed that these modification mechanisms proceed through transient phase (CaO, CaS) formation. In the case of spinels, preferential reduction of MgO part was also observed during calcium modification of spinels. The magnesium after MgO reduction by calcium can enter back into the melt or leave the melt in vapor form. The inclusion area fraction decreased after calcium treatment, but the inclusion concentration (number of inclusions per cm2) increased because inclusions shifted to a smaller size distribution after calcium treatment. Severe matrix effects during EDS analysis of inclusions were observed, due to which inclusion composition analyses can be significantly affected. *Please refer to dissertation for footnotes.

Determining the Binding Sites of β-Cyclodextrin and Peptides by Electron-Capture Dissociation High Resolution Tandem Mass Spectrometry

NASA Astrophysics Data System (ADS)

Qi, Yulin; Geib, Timon; Volmer, Dietrich A.

2015-07-01

Cyclodextrins (CDs) are a group of cyclic oligosaccharides, which readily form inclusion complexes with hydrophobic compounds to increase bioavailability, thus making CDs ideal drug excipients. Recent studies have also shown that CDs exhibit a wide range of protective effects, preventing proteins from aggregation, degradation, and folding. These effects strongly depend on the binding sites on the protein surface. CDs only exhibit weak interactions with amino acids, however; conventional analytical techniques therefore usually fail to reveal the exact location of the binding sites. Moreover, some studies even suggest that CD inclusion complexes are merely electrostatic adducts. Here, electron capture dissociation (ECD) was applied in this proof-of-concept study to examine the exact nature of the CD/peptide complexes, and CD binding sites were unambiguously located for the first time via Fourier-transform ion cyclotron resonance (FTICR) tandem mass spectrometry.

Dramatically Promoted Swelling of a Hydrogel by Pillar[6]arene-Ferrocene Complexation with Multistimuli Responsiveness.

PubMed

Ni, Mengfei; Zhang, Ning; Xia, Wei; Wu, Xuan; Yao, Chenhao; Liu, Xin; Hu, Xiao-Yu; Lin, Chen; Wang, Leyong

2016-05-25

The swelling-shrinking transition of hydrogels is crucial for their wide applications such as actuators and drug delivery. We hereby fabricated a smart hydrogel with ferrocene groups on pendant of polymer networks. While it was immersed in the water-soluble pillar[6]arene (WP6) aqueous solution, the hydrogel was dramatically swollen, which was an approximately 11-fold promotion in weight compared with that in pure water, due to the formation of the inclusion complexes between WP6 and ferrocene groups in the hydrogel. In particular, the well-swollen hydrogel exhibited good responsiveness to multistimuli including temperature, pH, redox, and competitive guests by tuning the dissociation/formation of WP6-ferrocene inclusion complexes or the strength of their charges. Meanwhile, potential application of such a smart hydrogel in pH-responsive drug release was demonstrated as well.

Bosniak Classification for Complex Renal Cysts Reevaluated: A Systematic Review.

PubMed

Schoots, Ivo G; Zaccai, Keren; Hunink, Myriam G; Verhagen, Paul C M S

2017-07-01

We systematically evaluated the Bosniak classification system with malignancy rates of each Bosniak category, and assessed the effectiveness related to surgical treatment and oncologic outcome based on recurrence and/or metastasis. In a systematic review according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement and the QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies) criteria, we selected 39 publications for inclusion in this analysis and categorized them into 1) surgical cohorts-all cysts treated surgically and 2) radiological cohorts-cysts with surgical treatment or radiological followup. A total of 3,036 complex renal cysts were categorized into Bosniak II, IIF, III and IV. In surgical and radiological cohorts pooled estimates showed a malignancy prevalence of 0.51 (0.44, 0.58) in Bosniak III and 0.89 (0.83, 0.92) in Bosniak IV cysts, respectively. Stable Bosniak IIF cysts showed a malignancy rate of less than 1% during radiological followup (surveillance). Bosniak IIF cysts, which showed reclassification to the Bosniak III/IV category during radiological followup (12%), showed malignancy in 85%, comparable to Bosniak IV cysts. The estimated surgical number needed to treat to avoid metastatic disease of Bosniak III and IV cysts was 140 and 40, respectively. The effectiveness of the Bosniak classification system for complex renal cysts was high in categories II, IIF and IV, but low in category III, and 49% of Bosniak III cysts was overtreated because of a benign outcome. This surgical overtreatment combined with the excellent outcome for Bosniak III cysts may suggest that surveillance is a rational alternative to surgery. This will require further study to assess whether surveillance of Bosniak III cysts will prove safe. Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Complex problems require complex solutions: the utility of social quality theory for addressing the Social Determinants of Health.

PubMed

Ward, Paul R; Meyer, Samantha B; Verity, Fiona; Gill, Tiffany K; Luong, Tini C N

2011-08-05

In order to improve the health of the most vulnerable groups in society, the WHO Commission on Social Determinants of Health (CSDH) called for multi-sectoral action, which requires research and policy on the multiple and inter-linking factors shaping health outcomes. Most conceptual tools available to researchers tend to focus on singular and specific social determinants of health (SDH) (e.g. social capital, empowerment, social inclusion). However, a new and innovative conceptual framework, known as social quality theory, facilitates a more complex and complete understanding of the SDH, with its focus on four domains: social cohesion, social inclusion, social empowerment and socioeconomic security, all within the same conceptual framework. This paper provides both an overview of social quality theory in addition to findings from a national survey of social quality in Australia, as a means of demonstrating the operationalisation of the theory. Data were collected using a national random postal survey of 1044 respondents in September, 2009. Multivariate logistic regression analysis was conducted. Statistical analysis revealed that people on lower incomes (less than $45000) experience worse social quality across all of the four domains: lower socio-economic security, lower levels of membership of organisations (lower social cohesion), higher levels of discrimination and less political action (lower social inclusion) and lower social empowerment. The findings were mixed in terms of age, with people over 65 years experiencing lower socio-economic security, but having higher levels of social cohesion, experiencing lower levels of discrimination (higher social inclusion) and engaging in more political action (higher social empowerment). In terms of gender, women had higher social cohesion than men, although also experienced more discrimination (lower social inclusion). Applying social quality theory allows researchers and policy makers to measure and respond to the multiple sources of oppression and advantage experienced by certain population groups, and to monitor the effectiveness of interventions over time.

Complex problems require complex solutions: the utility of social quality theory for addressing the Social Determinants of Health

PubMed Central

2011-01-01

Background In order to improve the health of the most vulnerable groups in society, the WHO Commission on Social Determinants of Health (CSDH) called for multi-sectoral action, which requires research and policy on the multiple and inter-linking factors shaping health outcomes. Most conceptual tools available to researchers tend to focus on singular and specific social determinants of health (SDH) (e.g. social capital, empowerment, social inclusion). However, a new and innovative conceptual framework, known as social quality theory, facilitates a more complex and complete understanding of the SDH, with its focus on four domains: social cohesion, social inclusion, social empowerment and socioeconomic security, all within the same conceptual framework. This paper provides both an overview of social quality theory in addition to findings from a national survey of social quality in Australia, as a means of demonstrating the operationalisation of the theory. Methods Data were collected using a national random postal survey of 1044 respondents in September, 2009. Multivariate logistic regression analysis was conducted. Results Statistical analysis revealed that people on lower incomes (less than $45000) experience worse social quality across all of the four domains: lower socio-economic security, lower levels of membership of organisations (lower social cohesion), higher levels of discrimination and less political action (lower social inclusion) and lower social empowerment. The findings were mixed in terms of age, with people over 65 years experiencing lower socio-economic security, but having higher levels of social cohesion, experiencing lower levels of discrimination (higher social inclusion) and engaging in more political action (higher social empowerment). In terms of gender, women had higher social cohesion than men, although also experienced more discrimination (lower social inclusion). Conclusions Applying social quality theory allows researchers and policy makers to measure and respond to the multiple sources of oppression and advantage experienced by certain population groups, and to monitor the effectiveness of interventions over time. PMID:21819576

The origin of fluids in the salt beds of the Delaware Basin, New Mexico and Texas

USGS Publications Warehouse

O'Neil, J.R.; Johnson, C.M.; White, L.D.; Roedder, E.

1986-01-01

Oxygen and hydrogen isotope analyses have been made of (1) brines from several wells in the salt deposits of the Delaware Basin, (2) inclusion fluids in halite crystals from the ERDA No. 9 site, and (3) local ground waters of meteoric origin. The isotopic compositions indicate that the brines are genetically related and that they probably originated from the evaporation of paleo-ocean waters. Although highly variable in solute contents, the brines have rather uniform isotopic compositions. The stable isotope compositions of brine from the ERDA No. 6 site (826.3 m depth) and fluid inclusions from the ERDA No. 9 site are variable but remarkably regular and show that (1) mixing with old or modern meteoric waters has occurred, the extent of mixing apparently decreasing with depth, and (2) water in the ERDA No. 6 brine may have originated from the dehydration of gypsum. Alternatively, the data may reflect simple evaporation of meteoric water on a previously dry marine flat. Stable isotope compositions of all the waters analyzed indicate that there has been fairly extensive mixing with ground water throughout the area, but that no significant circulation has occurred. The conclusions bear importantly on the suitability of these salt beds and others as repositories for nuclear waste. ?? 1986.

A complex magma mixing origin for rocks erupted in 1915, Lassen Peak, California

USGS Publications Warehouse

Clynne, M.A.

1999-01-01

The eruption of Lassen Peak in May 1915 produced four volcanic rock types within 3 days, and in the following order: (1) hybrid black dacite lava containing (2) undercooled andesitic inclusions, (3) compositionally banded pumice with dark andesite and light dacite bands, and (4) unbanded light dacite. All types represent stages of a complex mixing process between basaltic andesite and dacite that was interrupted by the eruption. They contain disequilibrium phenocryst assemblages characterized by the co-existence of magnesian olivine and quartz and by reacted and unreacted phenocrysts derived from the dacite. The petrography and crystal chemistry of the phenocrysts and the variation in rock compositions indicate that basaltic andesite intruded dacite magma and partially hybridized with it. Phenocrysts from the dacite magma were reacted. Cooling, cyrstallization, and vesiculation of the hybrid andesite magma converted it to a layer of mafic foam. The decreased density of the andesite magma destabilized and disrupted the foam. Blobs of foam rose into and were further cooled by the overlying dacite magma, forming the andesitic inclusions. Disaggregation of andesitic inclusions in the host dacite produced the black dacite and light dacite magmas. Formation of foam was a dynamic process. Removal of foam propagated the foam layer downward into the hybrid andesite magma. Eventually the thermal and compositional contrasts between the hybrid andesite and black dacite magmas were reduced. Then, they mixed directly, forming the dark andesite magma. About 40-50% andesitic inclusions were disaggregated into the host dacite to produce the hybrid black dacite. Thus, disaggregation of inclusions into small fragments and individual crystals can be an efficient magma-mixing process. Disaggregation of undercooled inclusions carrying reacted host-magma phenocrysts produces co-existing reacted and unreacted phenocrysts populations.

Formation kinetics and mechanism of metastable vacancy-dioxygen complex in neutron irradiated Czochralski silicon

NASA Astrophysics Data System (ADS)

Dong, Peng; Wang, Rong; Yu, Xuegong; Chen, Lin; Ma, Xiangyang; Yang, Deren

2017-07-01

We have quantitatively investigated the formation kinetics of metastable vacancy-dioxygen (VO2) complex in a structure of [VO + Oi], where a VO complex is trapped in a next-neighbor position to an interstitial oxygen atom (Oi). It is found that the VO annihilation is accompanied by the generation of metastable [VO + Oi] complex during annealing in the temperature range of 220-250 °C. The activation energy for [VO + Oi] generation appears at around 0.48 eV, which is much lower than the counterpart of stable VO2 complex. This indicates that the formation of [VO + Oi] complex originates from the reaction between VO and Oi. The ab initio calculations show that the formation energy of [VO + Oi] complex is larger than that of VO2 complex, which means that [VO + Oi] complex is thermodynamically unfavorable as compared to VO2 complex. However, the binding energy of [VO + Oi] complex is positive, indicating that [VO + Oi] complex is stable against decomposition of VO and Oi in silicon. It is believed that [VO + Oi] complex serves as the intermediate for VO to VO2 conversion.

Mechanisms Underlying the Formation of Complexes between Maize Starch and Lipids.

PubMed

Chao, Chen; Yu, Jinglin; Wang, Shuo; Copeland, Les; Wang, Shujun

2018-01-10

This study aimed to reveal the mechanism of formation of complexes between native maize starch (NMS) and different types of lipids, namely palmitic acid (PA), monopalmitate glycerol (MPG), dipalmitate glycerol (DPG), and tripalmitate glycerol (TPG). The complexing index followed the order of MPG (96.3%) > PA (41.8%) > TPG (8.3%) > DPG (1.1%), indicating that MPG formed more complexes with NMS than PA, and that few complexes were formed between NMS and DPG and TPG. The NMS-PA complex presented higher thermal transition temperatures and lower enthalpy change than the NMS-MPG complex, indicating that although MPG formed more starch complexes, they had less stable crystalline structures than the complex between NMS and PA. X-ray diffraction (XRD) and Raman spectroscopy showed that both MPG and PA formed V-type crystalline structures with NMS, and confirmed that no complexes were formed between NMS and DPG and TPG. We conclude that the monoglyceride formed more starch-lipid complex with maize starch than PA, but that the monoglyceride complex had a less stable structure than that formed with PA. The di- and triglycerides did not form complexes with maize starch.

Spray Dried Chitosan Microparticles for Intravesical Delivery of Celecoxib: Preparation and Characterization.

PubMed

Lopedota, Angela; Cutrignelli, Annalisa; Laquintana, Valentino; Denora, Nunzio; Iacobazzi, Rosa Maria; Perrone, Mara; Fanizza, Elisabetta; Mastrodonato, Maria; Mentino, Donatella; Lopalco, Antonio; Depalo, Nicoletta; Franco, Massimo

2016-09-01

Chitosan microparticles containing celecoxib (CB), were developed as chemoprevention of bladder cancer. Furthermore two inclusion complexes of CB with methyl-β-cyclodextrin (C1 and C2) were prepared to improve the solubility of the drug. C1 and C2 were obtained by freeze-drying and characterized in the solid state and in solution. Microparticles loaded with CB or C1 or C2 were prepared by spray drying and fully characterized. The yield and encapsulation efficiencies of microparticles depended by both the viscosity and the presence of the inclusion complex in the feed medium nebulised. Generally, the microparticles exhibited a spherical shape with mean diameter of approximately 2 μm which was compatible with local intravesical administration using a catheter. The CB release studies from the microparticles allowed us to identify both immediate release systems (microparticles including the complexes) and prolonged release systems (microparticles including CB alone). The latter exhibited good adhesion to the bladder mucosa, as highlighted by a mucoadhesion study. Histological studies revealed a desquamation of the superficial cells when the bladder mucosa was treated with microparticles loaded with CB, while the morphology of the urothelium did not change when it was treated with microparticles loaded with the inclusion complex. A new CB intravesical formulation than can easily be administered with a catheter and is able to release the drug at the target site for several hours was realized. This new delivery system could be a good alternative to classic oral CB administration.

Nanoaggregation of inclusion complexes of glibenclamide with cyclodextrins.

PubMed

Lucio, David; Irache, Juan Manuel; Font, María; Martínez-Ohárriz, María Cristina

2017-03-15

Glibenclamide is a sulfonylurea used for the oral treatment of type II diabetes mellitus. This drug shows low bioavailability as consequence of its low solubility. In order to solve this problem, the interaction with cyclodextrin has been proposed. This study tries to provide an explanation about the processes involved in the formation of GB-βCDs complexes, which have been interpreted in different ways by several authors. Among native cyclodextrins, βCD presents the most appropriate cavity to host glibenclamide molecules showing A L solubility diagrams (K 1:1 ≈1700M -1 ). However, [Formula: see text] solubility profiles were found for βCD derivatives, highlighting the coexistence of several phenomena involved in the drug solubility enhancement. At low CD concentration, the formation of inclusion complexes can be studied and the stability constants can be calculated (K 1:1 ≈1400M -1 ). Whereas at high CD concentration, the enhancement of GB solubility would be mainly attributed to the formation of nanoaggregates of CD and GB-CD complexes (sizes between 100 and 300nm). The inclusion mode into βCD occurs through the cyclohexyl ring of GB, adopting a semi-folded conformation which maximizes the hydrogen bond network. As consequence of all these phenomena, a 150-fold enhancement of drug solubility has been achieved using β-cyclodextrin derivatives. Thus, its use has proven to be an interesting tool to improve the oral administration of glibenclamide in accordance with dosage bulk and dose/solubility ratio requirements. Copyright © 2017 Elsevier B.V. All rights reserved.

Mathematical modelling of the transport of hydroxypropyl-β-cyclodextrin inclusion complexes of ranitidine hydrochloride and furosemide loaded chitosan nanoparticles across a Caco-2 cell monolayer.

PubMed

Sadighi, Armin; Ostad, S N; Rezayat, S M; Foroutan, M; Faramarzi, M A; Dorkoosh, F A

2012-01-17

Chitosan nanoparticles (CS-NPs) have been used to enhance the permeability of furosemide and ranitidine hydrochloride (ranitidine HCl) which were selected as candidates for two different biopharmaceutical drug classes having low permeability across Caco-2 cell monolayers. Drugs loaded CS-NPs were prepared by ionic gelation of CS and pentasodium tripolyphosphate (TPP) which added to the drugs inclusion complexes with hydroxypropyl-β-cyclodextrin (HP-βCD). The stability constants for furosemide/HP-βCD and ranitidine HCl/HP-βCD were calculated as 335 M(-1) and 410 M(-1), whereas the association efficiencies (AE%) of the drugs/HP-βCD inclusion complexes with CS-NPs were determined to be 23.0 and 19.5%, respectively. Zetasizer and scanning electron microscopy (SEM) were used to characterise drugs/HP-βCD-NPs size and morphology. Transport of both nano and non-nano formulations of drugs/HP-βCD complexes across a Caco-2 cell monolayer was assessed and fitted to mathematical models. Furosemide/HP-βCD-NPs demonstrated transport kinetics best suited for the Higuchi model, whereas other drug formulations demonstrated power law transportation behaviour. Permeability experiments revealed that furosemide/HP-βCD and ranitidine HCl/HP-βCD nano formulations greatly induce the opening of tight junctions and enhance drug transition through Caco-2 monolayers. Copyright © 2011 Elsevier B.V. All rights reserved.

[In-vitro evaluation of cinnarizine as a competing agent to beta-cyclodextrin inclusion complexes: effect of cinnarizine on the membrane permeation rate of progesterone from its beta-cyclodextrin inclusion complex].

PubMed

Muraoka, Atsushi; Tokumura, Tadakazu; Machida, Yoshiharu

2008-01-01

The use of competing agents is considered a powerful tool for the development of a drug-delivery system with drug/cyclodextrin inclusion complexes. However, there are very few studies examining this issue. To explain this phenomenon, it was thought that a competing agent with a sufficiently high stability constant had not yet been reported. In this study, cinnarizine (CN), which has a high stability constant with beta-cyclodextrin (beta-CD) and unique solubility characteristics, was selected, and its ability as a competing agent was examined in a membrane permeability study. The permeability study showed that the permeation rates of the drugs flurbiprofen, progesterone, and spironolactone decreased with their stability constants with the addition of beta-CD. In one of the drugs, progesterone (Pro), the decrease was restored by the addition of CN. The amount of CN added was a 1:1 molar ratio to the amount of Pro. However, no similar action was induced with the addition of DL-phenylalanine (Phe) in the permeation study at the 1:5 (Pro:Phe) molar ratio. These finding indicate that CN acts as a competing agent, and its action is much stronger than that of Phe.

Heat generated by dental implant drills during osteotomy-a review: heat generated by dental implant drills.

PubMed

Mishra, Sunil Kumar; Chowdhary, Ramesh

2014-06-01

Osseointegration is the more stable situation and results in a high success rate of dental implants. Heat generation during rotary cutting is one of the important factors influencing the development of osseointegration. To assess the various factors related to implant drills responsible for heat generation during osteotomy. To identify suitable literature, an electronic search was performed using Medline and Pubmed database. Articles published in between 1960 to February 2013 were searched. The search is focused on heat generated by dental implant drills during osteotomy. Various factors related to implant drill such effect of number of blades; drill design, drill fatigue, drill speed and force applied during osteotomies which were responsible for heat generation were reviewed. Titles and abstracts were screened, and literature that fulfilled the inclusion criteria was selected for a full-text reading. The initial literature search resulted in 299 articles out of which only 70 articles fulfils the inclusion criteria and were included in this systematic review. Many factors related to implant drill responsible for heat generation were found. Successful preparation of an implant cavity with minimal damage to the surrounding bone depends on the avoidance of excessive temperature generation during surgical drilling. The relationship between heat generated and implant drilling osteotomy is multifactorial in nature and its complexity has not been fully studied. Lack of scientific knowledge regarding this issue still exists. Further studies should be conducted to determine the various factors which generate less heat while osteotomy such as ideal ratio of force and speed in vivo, exact time to replace a drill, ideal drill design, irrigation system, drill-bone contact area.

Molecular Recognition: Detection of Colorless Compounds Based on Color Change

ERIC Educational Resources Information Center

Khalafi, Lida; Kashani, Samira; Karimi, Javad

2016-01-01

A laboratory experiment is described in which students measure the amount of cetirizine in allergy-treatment tablets based on molecular recognition. The basis of recognition is competition of cetirizine with phenolphthalein to form an inclusion complex with ß-cyclodextrin. Phenolphthalein is pinkish under basic condition, whereas it's complex form…

Learners with Profound and Complex Needs in Scotland's Colleges

ERIC Educational Resources Information Center

Her Majesty's Inspectorate of Education, 2009

2009-01-01

The Scottish Further and Higher Education Funding Council's (SFC) Corporate Plan (2009-12) makes clear its commitment to learners with profound and complex needs. Under "Outcome 2 Access, Inclusion and Progression" it states: "we will work with the Scottish Government, colleges and other stakeholders to ensure that appropriate…

Preparation and properties of amylose complexes prepared from hexadecylamine and its hydrochloride salt

USDA-ARS?s Scientific Manuscript database

Amylose inclusion complexes were prepared from jet-cooked aqueous mixtures of high amylose corn starch and 1-hexadecylamine (HDA). Slow-cooling produced torus/disc-shaped spherulites, whereas aggregates of smaller spherulites were obtained by rapid-cooling in ice. The morphologies and 6(1)V x-ray ...

Preparation of starch-stabilized silver nanoparticles from amylose-sodium palmitate inclusion complexes

USDA-ARS?s Scientific Manuscript database

Starch-stabilized silver nanoparticles were prepared from amylose-sodium palmitate complexes by first converting sodium palmitate to silver palmitate by reaction with silver nitrate and then reducing the silver ion to metallic silver. This process produced water solutions that could be dried and the...

Reduced Point Charge Models of Proteins: Effect of Protein-Water Interactions in Molecular Dynamics Simulations of Ubiquitin Systems.

PubMed

Leherte, Laurence; Vercauteren, Daniel P

2017-10-26

We investigate the influence of various solvent models on the structural stability and protein-water interface of three ubiquitin complexes (PDB access codes: 1Q0W , 2MBB , 2G3Q ) modeled using the Amber99sb force field (FF) and two different point charge distributions. A previously developed reduced point charge model (RPCM), wherein each amino acid residue is described by a limited number of point charges, is tested and compared to its all-atom (AA) version. The complexes are solvated in TIP4P-Ew or TIP3P type water molecules, involving either the scaling of the Lennard-Jones protein-O water interaction parameters, or the coarse-grain (CG) SIRAH water description. The best agreements between the RPCM and AA models were obtained for structural, protein-water, and ligand-ubiquitin properties when using the TIP4P-Ew water FF with a scaling factor γ of 0.7. At the RPCM level, a decrease in γ, or the inclusion of SIRAH particles, allows weakening of the protein-water interactions. It results in a slight collapse of the protein structure and a less compact hydration shell and, thus, in a decrease in the number of protein-water and water-water H-bonds. The dynamics of the surface protein atoms and of the water shell molecules are also slightly refrained, which allow the generation of stable RPCM trajectories.

Synergistic effect of signaling from receptors of soluble platelet agonists and outside-in signaling in formation of a stable fibrinogen-integrin αIIbβ3-actin cytoskeleton complex.

PubMed

Budnik, Ivan; Shenkman, Boris; Savion, Naphtali

2015-01-01

Thrombus formation in the injured vessel wall is a highly complex process involving various blood-born components that go through specific temporal and spatial changes as observed by intravital videomicroscopy. Platelets bind transiently to the developing thrombus and may either become stably incorporated into or disengage from the thrombus. The aim of the present study was to reveal the processes involved in the formation of a stable thrombus. Platelet-rich plasma and washed platelets were studied by the aggregometer. The aggregate stability was challenged by eptifibatide. Platelet Triton-insoluble fraction was prepared and the actin and αIIb content in the cytoskeleton was analyzed by western blot. Maximal actin polymerization is achieved 1min after platelet activation while maximal αIIbβ3-actin cytoskeleton association requires 5 to 10min of activation and fibrinogen-mediated platelet-to-platelet bridging. Thus, actin polymerization is dependent on platelet activation and requires neither αIIbβ3 integrin occupation nor platelet aggregation. Formation of a stable aggregate requires platelet activation for more than 1min, complete increase in actin cytoskeleton fraction and partial association of αIIbβ3 with the actin cytoskeleton. However, direct αIIbβ3 activation is not sufficient for cytoskeleton complex formation. Thus, stable αIIbβ3-fibrinogen interaction, representing stable aggregate, is achieved after more than 1min agonist activation, involving inside-out and outside-in signaling but not after direct integrin activation, involving only outside-in signaling. Formation of a stable fibrinogen-αIIbβ3-actin cytoskeleton complex is the result of the combined effect of platelet stimulation by soluble agonists, activation of αIIbβ3, fibrinogen binding and platelet-to-platelet bridging. Copyright © 2014 Elsevier Ltd. All rights reserved.

Attitudes towards the Inclusion of University Students with Disabilities: Development and Validation of a Scale Based on the Theory of Planned Behavior

ERIC Educational Resources Information Center

Fernández Faúndez, Eva María

2018-01-01

Introduction: The focus of our research converges on the analysis of attitudes and the prediction of the behavior of university students towards the inclusion of students with disabilities in university. The evaluation of attitudes and the prediction of behavior are complex, but it is fundamental because of the decisive impact they have on the…

The roles of fractional crystallization, magma mixing, crystal mush remobilization and volatile-melt interactions in the genesis of a young basalt-peralkaline rhyolite suite, the greater Olkaria volcanic complex, Kenya Rift valley

USGS Publications Warehouse

Macdonald, R.; Belkin, H.E.; Fitton, J.G.; Rogers, N.W.; Nejbert, K.; Tindle, A.G.; Marshall, A.S.

2008-01-01

The Greater Olkaria Volcanic Complex is a young (???20 ka) multi-centred lava and dome field dominated by the eruption of peralkaline rhyolites. Basaltic and trachytic magmas have been erupted peripherally to the complex and also form, with mugearites and benmoreites, an extensive suite of magmatic inclusions in the rhyolites. The eruptive rocks commonly represent mixed magmas and the magmatic inclusions are themselves two-, three- or four-component mixes. All rock types may carry xenocrysts of alkali feldspar, and less commonly plagioclase, derived from magma mixing and by remobilization of crystal mushes and/or plutonic rocks. Xenoliths in the range gabbro-syenite are common in the lavas and magmatic inclusions, the more salic varieties sometimes containing silicic glass representing partial melts and ranging in composition from anorthite ?? corundum- to acmite-normative. The peralkaline varieties are broadly similar, in major element terms, to the eruptive peralkaline rhyolites. The basalt-trachyte suite formed by a combination of fractional crystallization, magma mixing and resorption of earlier-formed crystals. Matrix glass in metaluminous trachytes has a peralkaline rhyolitic composition, indicating that the eruptive rhyolites may have formed by fractional crystallization of trachyte. Anomalous trace element enrichments (e.g. ??? 2000 ppm Y in a benmoreite) and negative Ce anomalies may have resulted from various Na- and K-enriched fluids evolving from melts of intermediate composition and either being lost from the system or enriched in other parts of the reservoirs. A small group of nepheline-normative, usually peralkaline, magmatic inclusions was formed by fluid transfer between peralkaline rhyolitic and benmoreitic magmas. The plumbing system of the complex consists of several independent reservoirs and conduits, repeatedly recharged by batches of mafic magma, with ubiquitous magma mixing. ?? The Author 2008. Published by Oxford University Press. All rights reserved.

Building an Open-source Simulation Platform of Acoustic Radiation Force-based Breast Elastography

PubMed Central

Wang, Yu; Peng, Bo; Jiang, Jingfeng

2017-01-01

Ultrasound-based elastography including strain elastography (SE), acoustic radiation force Impulse (ARFI) imaging, point shear wave elastography (pSWE) and supersonic shear imaging (SSI) have been used to differentiate breast tumors among other clinical applications. The objective of this study is to extend a previously published virtual simulation platform built for ultrasound quasi-static breast elastography toward acoustic radiation force-based breast elastography. Consequently, the extended virtual breast elastography simulation platform can be used to validate image pixels with known underlying soft tissue properties (i.e. “ground truth”) in complex, heterogeneous media, enhancing confidence in elastographic image interpretations. The proposed virtual breast elastography system inherited four key components from the previously published virtual simulation platform: an ultrasound simulator (Field II), a mesh generator (Tetgen), a finite element solver (FEBio) and a visualization and data processing package (VTK). Using a simple message passing mechanism, functionalities have now been extended to acoustic radiation force-based elastography simulations. Examples involving three different numerical breast models with increasing complexity – one uniform model, one simple inclusion model and one virtual complex breast model derived from magnetic resonance imaging data, were used to demonstrate capabilities of this extended virtual platform. Overall, simulation results were compared with the published results. In the uniform model, the estimated shear wave speed (SWS) values were within 4% compared to the predetermined SWS values. In the simple inclusion and the complex breast models, SWS values of all hard inclusions in soft backgrounds were slightly underestimated, similar to what has been reported. The elastic contrast values and visual observation show that ARFI images have higher spatial resolution, while SSI images can provide higher inclusion-to-background contrast. In summary, our initial results were consistent with our expectations and what have been reported in the literature. The proposed (open-source) simulation platform can serve as a single gateway to perform many elastographic simulations in a transparent manner, thereby promoting collaborative developments. PMID:28075330

SUPRAMOLECULAR COMPOSITE MATERIALS FROM CELLULOSE, CHITOSAN AND CYCLODEXTRIN: FACILE PREPARATION AND THEIR SELECTIVE INCLUSION COMPLEX FORMATION WITH ENDOCRINE DISRUPTORS

PubMed Central

Duri, Simon; Tran, Chieu D.

2013-01-01

We have successfully developed a simple and one step method to prepare high performance supramolecular polysaccharide composites from cellulose (CEL), chitosan (CS) and (2,3,6-tri-O-acetyl)-α-, β- and γ-cyclodextrin (α-, β- and γ-TCD). In this method, [BMIm+Cl−], an ionic liquid (IL), was used as a solvent to dissolve and prepare the composites. Since majority (>88%) of the IL used was recovered for reuse, the method is recyclable. XRD, FT-IR, NIR and SEM were used to monitor the dissolution process and to confirm that the polysaccharides were regenerated without any chemical modifications. It was found that unique properties of each component including superior mechanical properties (from CEL), excellent adsorbent for pollutants and toxins (from CS) and size/structure selectivity through inclusion complex formation (from TCDs) remain intact in the composites. Specifically, results from kinetics and adsorption isotherms show that while CS-based composites can effectively adsorb the endocrine disruptors (polychlrophenols, bisphenol-A), its adsorption is independent on the size and structure of the analytes. Conversely, the adsorption by γ-TCD-based composites exhibits strong dependency on size and structure of the analytes. For example, while all three TCD-based composites (i.e., α-, β- and γ-TCD) can effectively adsorb 2-, 3- and 4-chlorophenol, only γ-TCD-based composite can adsorb analytes with bulky groups including 3,4-dichloro- and 2,4,5-trichlorophenol. Furthermore, equilibrium sorption capacities for the analytes with bulky groups by γ-TCD-based composite are much higher than those by CS-based composites. Together, these results indicate that γ-TCD-based composite with its relatively larger cavity size can readily form inclusion complexes with analytes with bulky groups, and through inclusion complex formation, it can strongly adsorb much more analytes and with size/structure selectivity compared to CS-based composites which can adsorb the analyte only by surface adsorption. PMID:23517477

Reactive sputter deposition of piezoelectric Sc 0.12Al 0.88N for contour mode resonators

DOE PAGES

Henry, Michael David; Young, Travis Ryan; Douglas, Erica Ann; ...

2018-05-11

Substitution of Al by Sc has been predicted and demonstrated to improve the piezoelectric response in AlN for commercial market applications in radio frequency filter technologies. Although cosputtering with multiple targets have achieved Sc incorporation in excess of 40%, industrial processes requiring stable single target sputtering are currently limited. A major concern with sputter deposition of ScAl is the control over the presence of non-c-axis oriented crystal growth, referred to as inclusions here, while simultaneously controlling film stress for suspended microelectromechanical systems (MEMS) structures. In this paper, we describe 12.5% ScAl single target reactive sputter deposition process and establishes amore » direct relationship between the inclusion occurrences and compressive film stress allowing for the suppression of the c-axis instability on silicon (100) and Ti/TiN/AlCu seeding layers. An initial high film stress, for suppressing inclusions, is then balanced with a lower film stress deposition to control total film stress to prevent Euler buckling of suspended MEMS devices. Contour mode resonators fabricated using these films demonstrate effective coupling coefficients up to 2.7% with figures of merit of 42. Finally, this work provides a method to establish inclusion free films in ScAlN piezoelectric films for good quality factor devices.« less

Reactive sputter deposition of piezoelectric Sc 0.12Al 0.88N for contour mode resonators

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

Henry, Michael David; Young, Travis Ryan; Douglas, Erica Ann

Substitution of Al by Sc has been predicted and demonstrated to improve the piezoelectric response in AlN for commercial market applications in radio frequency filter technologies. Although cosputtering with multiple targets have achieved Sc incorporation in excess of 40%, industrial processes requiring stable single target sputtering are currently limited. A major concern with sputter deposition of ScAl is the control over the presence of non-c-axis oriented crystal growth, referred to as inclusions here, while simultaneously controlling film stress for suspended microelectromechanical systems (MEMS) structures. In this paper, we describe 12.5% ScAl single target reactive sputter deposition process and establishes amore » direct relationship between the inclusion occurrences and compressive film stress allowing for the suppression of the c-axis instability on silicon (100) and Ti/TiN/AlCu seeding layers. An initial high film stress, for suppressing inclusions, is then balanced with a lower film stress deposition to control total film stress to prevent Euler buckling of suspended MEMS devices. Contour mode resonators fabricated using these films demonstrate effective coupling coefficients up to 2.7% with figures of merit of 42. Finally, this work provides a method to establish inclusion free films in ScAlN piezoelectric films for good quality factor devices.« less

Reactive sputter deposition of piezoelectric Sc 0.12Al 0.88N for contour mode resonators

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

Henry, Michael David; Young, Travis Ryan; Douglas, Erica Ann

Substitution of Al by Sc has been predicted and demonstrated to improve the piezoelectric response in AlN for commercial market applications in radio frequency filter technologies. Although cosputtering with multiple targets have achieved Sc incorporation in excess of 40%, industrial processes requiring stable single target sputtering are currently limited. A major concern with sputter deposition of ScAl is the control over the presence of non-c-axis oriented crystal growth, referred to as inclusions here, while simultaneously controlling film stress for suspended microelectromechanical systems (MEMS) structures. This work describes 12.5% ScAl single target reactive sputter deposition process and establishes a direct relationshipmore » between the inclusion occurrences and compressive film stress allowing for the suppression of the c-axis instability on silicon (100) and Ti/TiN/AlCu seeding layers. An initial high film stress, for suppressing inclusions, is then balanced with a lower film stress deposition to control total film stress to prevent Euler buckling of suspended MEMS devices. Contour mode resonators fabricated using these films demonstrate effective coupling coefficients up to 2.7% with figures of merit of 42. Furthermore, this work provides a method to establish inclusion free films in ScAlN piezoelectric films for good quality factor devices.« less

Repeated-batch operation of immobilized β-galactosidase inclusion bodies-containing Escherichia coli cell reactor for lactose hydrolysis.

PubMed

Yeon, Ji-Hyeon; Jung, Kyung-Hwan

2011-09-01

In this study, we investigated the performance of an immobilized β-galactosidase inclusion bodies-containing Escherichia coli cell reactor, where the cells were immobilized in alginate beads, which were then used in repeated-batch operations for the hydrolysis of o-nitrophenyl-β-D-galactoside or lactose over the long-term. In particular, in the Tris buffer system, disintegration of the alginate beads was not observed during the operation, which was observed for the phosphate buffer system. The o-nitrophenyl-β-D-galactoside hydrolysis was operated successfully up to about 80 h, and the runs were successfully repeated at least eight times. In addition, hydrolysis of lactose was successfully carried out up to 240 h. Using Western blotting analyses, it was verified that the beta-galactosidase inclusion bodies were sustained in the alginate beads during the repeated-batch operations. Consequently, we experimentally verified that β-galactosidase inclusion bodies-containing Escherichia coli cells could be used in a repeated-batch reactor as a biocatalyst for the hydrolysis of o-nitrophenyl-β-D-galactoside or lactose. It is probable that this approach can be applied to enzymatic synthesis reactions for other biotechnology applications, particularly reactions that require long-term and stable operation.

C-Terminal Tyrosine Residue Modifications Modulate the Protective Phosphorylation of Serine 129 of α-Synuclein in a Yeast Model of Parkinson's Disease

PubMed Central

Lázaro, Diana F.; Pinho, Raquel; Valerius, Oliver; Outeiro, Tiago F.; Braus, Gerhard H.

2016-01-01

Parkinson´s disease (PD) is characterized by the presence of proteinaceous inclusions called Lewy bodies that are mainly composed of α-synuclein (αSyn). Elevated levels of oxidative or nitrative stresses have been implicated in αSyn related toxicity. Phosphorylation of αSyn on serine 129 (S129) modulates autophagic clearance of inclusions and is prominently found in Lewy bodies. The neighboring tyrosine residues Y125, Y133 and Y136 are phosphorylation and nitration sites. Using a yeast model of PD, we found that Y133 is required for protective S129 phosphorylation and for S129-independent proteasome clearance. αSyn can be nitrated and form stable covalent dimers originating from covalent crosslinking of two tyrosine residues. Nitrated tyrosine residues, but not di-tyrosine-crosslinked dimers, contributed to αSyn cytotoxicity and aggregation. Analysis of tyrosine residues involved in nitration and crosslinking revealed that the C-terminus, rather than the N-terminus of αSyn, is modified by nitration and di-tyrosine formation. The nitration level of wild-type αSyn was higher compared to that of A30P mutant that is non-toxic in yeast. A30P formed more dimers than wild-type αSyn, suggesting that dimer formation represents a cellular detoxification pathway in yeast. Deletion of the yeast flavohemoglobin gene YHB1 resulted in an increase of cellular nitrative stress and cytotoxicity leading to enhanced aggregation of A30P αSyn. Yhb1 protected yeast from A30P-induced mitochondrial fragmentation and peroxynitrite-induced nitrative stress. Strikingly, overexpression of neuroglobin, the human homolog of YHB1, protected against αSyn inclusion formation in mammalian cells. In total, our data suggest that C-terminal Y133 plays a major role in αSyn aggregate clearance by supporting the protective S129 phosphorylation for autophagy and by promoting proteasome clearance. C-terminal tyrosine nitration increases pathogenicity and can only be partially detoxified by αSyn di-tyrosine dimers. Our findings uncover a complex interplay between S129 phosphorylation and C-terminal tyrosine modifications of αSyn that likely participates in PD pathology. PMID:27341336

C-Terminal Tyrosine Residue Modifications Modulate the Protective Phosphorylation of Serine 129 of α-Synuclein in a Yeast Model of Parkinson's Disease.

PubMed

Kleinknecht, Alexandra; Popova, Blagovesta; Lázaro, Diana F; Pinho, Raquel; Valerius, Oliver; Outeiro, Tiago F; Braus, Gerhard H

2016-06-01

Parkinson´s disease (PD) is characterized by the presence of proteinaceous inclusions called Lewy bodies that are mainly composed of α-synuclein (αSyn). Elevated levels of oxidative or nitrative stresses have been implicated in αSyn related toxicity. Phosphorylation of αSyn on serine 129 (S129) modulates autophagic clearance of inclusions and is prominently found in Lewy bodies. The neighboring tyrosine residues Y125, Y133 and Y136 are phosphorylation and nitration sites. Using a yeast model of PD, we found that Y133 is required for protective S129 phosphorylation and for S129-independent proteasome clearance. αSyn can be nitrated and form stable covalent dimers originating from covalent crosslinking of two tyrosine residues. Nitrated tyrosine residues, but not di-tyrosine-crosslinked dimers, contributed to αSyn cytotoxicity and aggregation. Analysis of tyrosine residues involved in nitration and crosslinking revealed that the C-terminus, rather than the N-terminus of αSyn, is modified by nitration and di-tyrosine formation. The nitration level of wild-type αSyn was higher compared to that of A30P mutant that is non-toxic in yeast. A30P formed more dimers than wild-type αSyn, suggesting that dimer formation represents a cellular detoxification pathway in yeast. Deletion of the yeast flavohemoglobin gene YHB1 resulted in an increase of cellular nitrative stress and cytotoxicity leading to enhanced aggregation of A30P αSyn. Yhb1 protected yeast from A30P-induced mitochondrial fragmentation and peroxynitrite-induced nitrative stress. Strikingly, overexpression of neuroglobin, the human homolog of YHB1, protected against αSyn inclusion formation in mammalian cells. In total, our data suggest that C-terminal Y133 plays a major role in αSyn aggregate clearance by supporting the protective S129 phosphorylation for autophagy and by promoting proteasome clearance. C-terminal tyrosine nitration increases pathogenicity and can only be partially detoxified by αSyn di-tyrosine dimers. Our findings uncover a complex interplay between S129 phosphorylation and C-terminal tyrosine modifications of αSyn that likely participates in PD pathology.

Understanding the mechanism of DNA deactivation in ion therapy of cancer cells: hydrogen peroxide action*

NASA Astrophysics Data System (ADS)

Piatnytskyi, Dmytro V.; Zdorevskyi, Oleksiy O.; Perepelytsya, Sergiy M.; Volkov, Sergey N.

2015-11-01

Changes in the medium of biological cells under ion beam irradiation has been considered as a possible cause of cell function disruption in the living body. The interaction of hydrogen peroxide, a long-lived molecular product of water radiolysis, with active sites of DNA macromolecule was studied, and the formation of stable DNA-peroxide complexes was considered. The phosphate groups of the macromolecule backbone were picked out among the atomic groups of DNA double helix as a probable target for interaction with hydrogen peroxide molecules. Complexes consisting of combinations including: the DNA phosphate group, H2O2 and H2O molecules, and Na+ counterion, were considered. The counterions have been taken into consideration insofar as under the natural conditions they neutralise DNA sugar-phosphate backbone. The energy of the complexes have been determined by considering the electrostatic and the Van der Waals interactions within the framework of atom-atom potential functions. As a result, the stability of various configurations of molecular complexes was estimated. It was shown that DNA phosphate groups and counterions can form stable complexes with hydrogen peroxide molecules, which are as stable as the complexes with water molecules. It has been demonstrated that the formation of stable complexes of H2O2-Na+-PO4- may be detected experimentally by observing specific vibrations in the low-frequency Raman spectra. The interaction of H2O2 molecule with phosphate group of the double helix backbone can disrupt DNA biological function and induce the deactivation of the cell genetic apparatus. Thus, the production of hydrogen peroxide molecules in the nucleus of living cells can be considered as an additional mechanism by which high-energy ion beams destroy tumour cells during ion beam therapy. Contribution to the Topical Issue "COST Action Nano-IBCT: Nano-scale Processes Behind Ion-Beam Cancer Therapy", edited by Andrey Solov'yov, Nigel Mason, Gustavo García, Eugene Surdutovich.

Relevant role of dissolved humic matter in phosphorus bioavailability in natural and agronomical ecosystems through the formation of Humic-(Metal)-Phosphate complexes

NASA Astrophysics Data System (ADS)

Baigorri, Roberto; Urrutia, Óscar; Erro, Javier; Pazos-Pérez, Nicolás; María García-Mina, José

2016-04-01

Natural Organic Matter (NOM) and the NOM fraction present in soil solution (dissolved organic matter: DOM) are currently considered as fundamental actors in soil fertility and crop mineral nutrition. Indeed, decreases in crop yields as well as soil erosion are closely related to low values of NOM and, in fact, the use of organic amendments as both soil improvers and plant growth enhancers is very usual in countries with soils poor in NOM. This role of NOM (and DOM) seems to be associated with the presence of bio-transformed organic molecules (humic substances) with high cation chelating-complexing ability. In fact, bioavailable micronutrients with metallic character in soil solutions of alkaline and calcareous soils are forming stable complexes with DOM. This beneficial action of DOM also concerns other plant nutrients such as inorganic phosphate (Pi). Among the different mechanisms involved in the beneficial action of DOM on P bioavailability, the possible formation of poly-nuclear complexes including stable chemical bonds between negative binding sites in humic substances and Pi through metal bridges in soil solution might be relevant, especially in acidic soils. In fact, several studies have proven that these complexes can be obtained in the laboratory and are very efficient in prevent Pi soil fixation and improve Pi root uptake. However, clear experimental evidence about their presence in soil solutions of natural and agronomical soil ecosystems has not published yet. We present here experimental results supporting the real presence of stable Pi-metal-Humic (PMH) complexes in the soil solution of several acidic soils. The study is based on the physico-chemical characterization (31P-NMR, FTIR, TEM-EDAX, ICP-OES) of the DOM fraction isolated by ultrafiltration from the soil solution of several representative acidic soils. In average, more than 60 % of Pi was found in the soil solution humic fraction forming stable humic-metal (Fe, Al) complexes.

Energetic Ionic Liquids Based on Anionic Rare Earth Nitrate Complexes (Preprint)

DTIC Science & Technology

2008-07-10

a glass transition temperature (Tg) at -46 oC. However, it is only stable in dry air, and thus must be protected from water. At 75 oC, clear weight...involved highly toxic and corrosive chemicals, N2O4 and NOCl. Ligands which coordinate via oxygen atoms to a rare earth metal ion give rise to stable...complexes. Thus higher air and thermal stabilities may be obtained by introducing rare earth metal nitrates as main components of ionic liquids. We

Characterization of human glucocorticoid receptor complexes formed with DNA fragments containing or lacking glucocorticoid response elements

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

Tully, D.B.; Cidlowski, J.A.

1989-03-07

Sucrose density gradient shift assays were used to study the interactions of human glucocorticoid receptors (GR) with small DNA fragments either containing or lacking glucocorticoid response element (GRE) DNA consensus sequences. When crude cytoplasmic extracts containing ({sup 3}H)triamcinolone acetonide (({sup 3}H)TA) labeled GR were incubated with unlabeled DNA under conditions of DNA excess, a GRE-containing DNA fragment obtained from the 5' long terminal repeat of mouse mammary tumor virus (MMTV LTR) formed a stable 12-16S complex with activated, but not nonactivated, ({sup 3}H)TA receptor. By contrast, if the cytosols were treated with calf thymus DNA-cellulose to deplete non-GR-DNA-binding proteins priormore » to heat activation, a smaller 7-10S complex was formed with the MMTV LTR DNA fragment. Activated ({sup 3}H)TA receptor from DNA-cellulose pretreated cytosols also interacted with two similarly sized fragments from pBR322 DNA. Stability of the complexes formed between GR and these three DNA fragments was strongly affected by even moderate alterations in either the salt concentration or the pH of the gradient buffer. Under all conditions tested, the complex formed with the MMTV LTR DNA fragment was more stable than the complexes formed with either of the pBR322 DNA fragments. Together these observations indicate that the formation of stable complexes between activated GR and isolated DNA fragments requires the presence of GRE consensus sequences in the DNA.« less

Fluid Inclusion Study of Quartz Xenocrysts in Mafic Dykes from Kawant Area, Chhota Udaipur District, Gujarat, India

NASA Astrophysics Data System (ADS)

Randive, Kirtikumar; Hurai, Vratislav

2015-09-01

Unusual mafic dykes occur in the proximity of the Ambadongar Carbonatite Complex, Lower Narmada Valley, Gujarat, India. The dykes contain dense population of quartz xenocrysts within the basaltic matrix metasomatised by carbonate-rich fluids. Plagioclase feldspars, relict pyroxenes, chlorite, barite, rutile, magnetite, Fe-Ti oxides and glass were identified in the basaltic matrix. Quartz xenocrysts occur in various shapes and sizes and form an intricate growth pattern with carbonates. The xenocrysts are fractured and contain several types of primary and secondary, single phase and two-phase fluid inclusions. The two-phase inclusions are dominated by aqueous liquid, whereas the monophase inclusions are composed of carbonic gas and the aqueous inclusions homogenize to liquid between 226°C and 361°C. Majority of the inclusions are secondary in origin and are therefore unrelated to the crystallization of quartz. Moreover, the inclusions have mixed carbonic-aqueous compositions that inhibit their direct correlation with the crustal or mantle fluids. The composition of dilute CO2-rich fluids observed in the quartz xenocrysts appear similar to those exsolved during the final stages of evolution of the Amba Dongar carbonatites. However, the carbonates are devoid of fluid inclusions and therefore their genetic relation with the quartz xenocrysts cannot be established.

Pressure-temperature-fluid constraints for the Emmaville-Torrington emerald deposit, New South Wales, Australia: Fluid inclusion and stable isotope studies

NASA Astrophysics Data System (ADS)

Loughrey, Lara; Marshall, Dan; Jones, Peter; Millsteed, Paul; Main, Arthur

2012-06-01

The Emmaville-Torrington emeralds were first discovered in 1890 in quartz veins hosted within a Permian metasedimentary sequence, consisting of meta-siltstones, slates and quartzites intruded by pegmatite and aplite veins from the Moule Granite. The emerald deposit genesis is consistent with a typical granite-related emerald vein system. Emeralds from these veins display colour zonation alternating between emerald and clear beryl. Two fluid inclusion types are identified: three-phase (brine+vapour+halite) and two-phase (vapour+liquid) fluid inclusions. Fluid inclusion studies indicate the emeralds were precipitated from saline fluids ranging from approximately 33 mass percent NaCl equivalent. Formational pressures and temperatures of 350 to 400 °C and approximately 150 to 250 bars were derived from fluid inclusion and petrographic studies that also indicate emerald and beryl precipitation respectively from the liquid and vapour portions of a two-phase (boiling) system. The distinct colour zonations observed in the emerald from these deposits is the first recorded emerald locality which shows evidence of colour variation as a function of boiling. The primary three-phase and primary two-phase FITs are consistent with alternating chromium-rich `striped' colour banding. Alternating emerald zones with colourless beryl are due to chromium and vanadium partitioning in the liquid portion of the boiling system. The chemical variations observed at Emmaville-Torrington are similar to other colour zoned emeralds from other localities worldwide likely precipitated from a boiling system as well.

Engineering tumor cell targeting in nanoscale amyloidal materials

NASA Astrophysics Data System (ADS)

Unzueta, Ugutz; Seras-Franzoso, Joaquin; Virtudes Céspedes, María; Saccardo, Paolo; Cortés, Francisco; Rueda, Fabián; Garcia-Fruitós, Elena; Ferrer-Miralles, Neus; Mangues, Ramon; Vázquez, Esther; Villaverde, Antonio

2017-01-01

Bacterial inclusion bodies are non-toxic, mechanically stable and functional protein amyloids within the nanoscale size range that are able to naturally penetrate into mammalian cells, where they deliver the embedded protein in a functional form. The potential use of inclusion bodies in protein delivery or protein replacement therapies is strongly impaired by the absence of specificity in cell binding and penetration, thus preventing targeting. To address this issue, we have here explored whether the genetic fusion of two tumor-homing peptides, the CXCR4 ligands R9 and T22, to an inclusion body-forming green fluorescent protein (GFP), would keep the interaction potential and the functionality of the fused peptides and then confer CXCR4 specificity in cell binding and further uptake of the materials. The fusion proteins have been well produced in Escherichia coli in their full-length form, keeping the potential for fluorescence emission of the partner GFP. By using specific inhibitors of CXCR4 binding, we have demonstrated that the engineered protein particles are able to penetrate CXCR4+ cells, in a receptor-mediated way, without toxicity or visible cytopathic effects, proving the availability of the peptide ligands on the surface of inclusion bodies. Since no further modification is required upon their purification, the biological production of genetically targeted inclusion bodies opens a plethora of cost-effective possibilities in the tissue-specific intracellular transfer of functional proteins through the use of structurally and functionally tailored soft materials.

Inclusion compound of vitamin B6 in β-CD. Physico-chemical and structural investigations

NASA Astrophysics Data System (ADS)

Borodi, Gheorghe; Kacso, Irina; Farcaş, Sorin I.; Bratu, Ioan

2009-08-01

Structural and physico-chemical characterization of supramolecular assembly of vitamin B6 with β-cyclodextrin (β-CD) prepared by different methods (kneading, co-precipitation and freeze-drying) has been performed by using several spectroscopic techniques (FTIR, 1H NMR, UV-Vis), powder X-ray diffraction and DSC in order to evidence the inclusion compound formation. An analysis of the chemical shifts observed in the 1H-NMR spectra and of the vibrational frequency shifts led to the tentative conclusion that the vitamin B6 probably enters the cyclodextrin torus when forming the β-CD-vitamin B6 inclusion complex.

Association between eotaxin (CCL11), C-reactive protein, and antimicrobial antibodies in patients undergoing coronary angioplasty.

PubMed

Kaehler, Jan; Tuleweit, Anika; Steven, Daniel; Krempl, Tanja; Haar, Antje; Carstensen, Marion; Koester, Ralf; Terres, Wolfram; Meinertz, Thomas

2006-12-01

Eotaxin (CCL11) is a potent chemoattractant for eosinophils and lymphocytes. Apart from its functions in the eosinophilic system, eotaxin has been shown to be overexpressed in atherosclerosis. We therefore sought to determine whether chronic infection with Chlamydia pneumoniae or other infectious agents is correlated with concentrations of eotaxin or C-reactive protein since this mechanism could explain the finding that chronic infection stimulates smooth muscle cell migration and plaque development. Patients undergoing percutaneous coronary angioplasty (PCI) for acute coronary syndrome or stable angina were included in the study. Blood was drawn before PCI, at 6 weeks, and 6 and 12 months after coronary intervention. Eotaxin and C-reactive protein were determined by enzyme-linked immunosorbent assay (ELISA). Antibodies against Candida, C. pneumoniae, cytomegalovirus, Helicobacter pylori, and herpes simplex virus were measured by ELISA or immunofluorescence. Two hundred five consecutive patients undergoing PCI (stable angina, n = 136; acute coronary syndrome, n = 69) and 83 patients with normal coronary arteries were enrolled in the study. Eotaxin concentrations at inclusion were higher in patients with coronary artery disease than in control patients, p = .01, and comparable in patients with stable angina and those with acute coronary syndrome but did not correlate with C-reactive protein. Eotaxin concentrations at inclusion and during follow-up weakly correlated with concentrations of antibodies against C. pneumoniae, H. pylori, and herpes simplex virus but not with concentrations of antibodies against Candida or cytomegalovirus. Eotaxin concentrations and antibody titers against C. pneumoniae significantly increased following angioplasty and remained elevated thereafter. In conclusion, our data demonstrate that eotaxin concentrations are elevated independently from C-reactive protein in patients with coronary artery disease and correlate with antibodies against infectious agents known for chronic infection in humans.

The hydrothermal evolution of the Kawerau geothermal system, New Zealand

NASA Astrophysics Data System (ADS)

Milicich, S. D.; Chambefort, I.; Wilson, C. J. N.; Charlier, B. L. A.; Tepley, F. J.

2018-03-01

Hydrothermal alteration zoning and processes provide insights into the evolution of heat source(s) and fluid compositions associated with geothermal systems. Traditional petrological techniques, combined with hydrothermal alteration studies, stable isotope analyses and geochronology can resolve the nature of the fluids involved in hydrothermal processes and their changes through time. We report here new findings along with previous unpublished works on alteration patterns, fluid inclusion measurements and stable isotope data to provide insights into the thermal and chemical evolution of the Kawerau geothermal system, New Zealand. These data indicate the presence of two hydrothermal events that can be coupled with chronological data. The earlier period of hydrothermal activity was initiated at 400 ka, with the heat driving the hydrothermal system inferred to be from the magmatic system that gave rise to rhyolite lavas and sills of the Caxton Formation. Isotopic data fingerprint fluids attributed to this event as meteoric, indicating that the magma primarily served as a heat source driving fluid circulation, and was not releasing magmatic fluids in sufficient quantity to affect the rock mineralogy and thus inferred fluid compositions. The modern Kawerau system was initiated at 16 ka with hydrothermal eruptions linked to shallow intrusion of magma at the onset of activity that gave rise to the Putauaki andesite cone. Likely associated with this later event was a pulse of magmatic CO2, resulting in large-scale deposition of hydrothermal calcite enriched in 18O. Meteoric water-dominated fluids subsequently overwhelmed the magmatic fluids associated with this 18O-rich signature, and both the fluid inclusion microthermometry and stable isotope data reflect a change to the present-day fluid chemistry of low salinity, meteoric-dominated waters.

Structural characterization of recombinant IAV polymerase reveals a stable complex between viral PA-PB1 heterodimer and host RanBP5.

PubMed

Swale, Christopher; Monod, Alexandre; Tengo, Laura; Labaronne, Alice; Garzoni, Frédéric; Bourhis, Jean-Marie; Cusack, Stephen; Schoehn, Guy; Berger, Imre; Ruigrok, Rob W H; Crépin, Thibaut

2016-04-20

The genome of influenza A virus (IAV) comprises eight RNA segments (vRNA) which are transcribed and replicated by the heterotrimeric IAV RNA-dependent RNA-polymerase (RdRp). RdRp consists of three subunits (PA, PB1 and PB2) and binds both the highly conserved 3'- and 5'-ends of the vRNA segment. The IAV RdRp is an important antiviral target, but its structural mechanism has remained largely elusive to date. By applying a polyprotein strategy, we produced RdRp complexes and define a minimal human IAV RdRp core complex. We show that PA-PB1 forms a stable heterodimeric submodule that can strongly interact with 5'-vRNA. In contrast, 3'-vRNA recognition critically depends on the PB2 N-terminal domain. Moreover, we demonstrate that PA-PB1 forms a stable and stoichiometric complex with host nuclear import factor RanBP5 that can be modelled using SAXS and we show that the PA-PB1-RanPB5 complex is no longer capable of 5'-vRNA binding. Our results provide further evidence for a step-wise assembly of IAV structural components, regulated by nuclear transport mechanisms and host factor binding.

Association Mechanisms of Unsaturated C2 Hydrocarbons with Their Cations: Acetylene and Ethylene

NASA Technical Reports Server (NTRS)

Bera, Partha P.; Head-Gordon, Martin; Lee, Timothy J.

2013-01-01

The ion-molecule association mechanism of acetylene and ethylene with their cations is investigated by ab initio quantum chemical methods to understand the structures, association energies, and the vibrational and electronic spectra of the products. Stable puckered cyclic isomers are found as the result of first forming less stable linear and bridge isomers. The puckered cyclic complexes are calculated to be strongly bound, by 87, 35 and 56 kcal/mol for acetylene-acetylene cation, ethylene-ethylene cation and acetylene-ethylene cation, respectively. These stable complexes may be intermediates that participate in further association reactions. There are no association barriers, and no significant inter-conversion barriers, so the initial linear and bridge encounter complexes are unlikely to be observable. However, the energy gap between the bridged and cyclic puckered isomers greatly differs from complex to complex: it is 44 kcal/mol in C4H4 +, but only 6 kcal/mol in C4H8 +. The accurate CCSD(T) calculations summarized above are also compared against less computationally expensive MP2 and density functional theory (DFT) calculations for structures, relative energies, and vibrational spectra. Calculated vibrational spectra are compared against available experiments for cyclobutadiene cation. Electronic spectra are also calculated using time-dependent DFT.

Effects of expected-value information and display format on recognition of aircraft subsystem abnormalities

NASA Technical Reports Server (NTRS)

Palmer, Michael T.; Abbott, Kathy H.

1994-01-01

This study identifies improved methods to present system parameter information for detecting abnormal conditions and to identify system status. Two workstation experiments were conducted. The first experiment determined if including expected-value-range information in traditional parameter display formats affected subject performance. The second experiment determined if using a nontraditional parameter display format, which presented relative deviation from expected value, was better than traditional formats with expected-value ranges included. The inclusion of expected-value-range information onto traditional parameter formats was found to have essentially no effect. However, subjective results indicated support for including this information. The nontraditional column deviation parameter display format resulted in significantly fewer errors compared with traditional formats with expected-value-ranges included. In addition, error rates for the column deviation parameter display format remained stable as the scenario complexity increased, whereas error rates for the traditional parameter display formats with expected-value ranges increased. Subjective results also indicated that the subjects preferred this new format and thought that their performance was better with it. The column deviation parameter display format is recommended for display applications that require rapid recognition of out-of-tolerance conditions, especially for a large number of parameters.

A non-linear data mining parameter selection algorithm for continuous variables

PubMed Central

Razavi, Marianne; Brady, Sean

2017-01-01

In this article, we propose a new data mining algorithm, by which one can both capture the non-linearity in data and also find the best subset model. To produce an enhanced subset of the original variables, a preferred selection method should have the potential of adding a supplementary level of regression analysis that would capture complex relationships in the data via mathematical transformation of the predictors and exploration of synergistic effects of combined variables. The method that we present here has the potential to produce an optimal subset of variables, rendering the overall process of model selection more efficient. This algorithm introduces interpretable parameters by transforming the original inputs and also a faithful fit to the data. The core objective of this paper is to introduce a new estimation technique for the classical least square regression framework. This new automatic variable transformation and model selection method could offer an optimal and stable model that minimizes the mean square error and variability, while combining all possible subset selection methodology with the inclusion variable transformations and interactions. Moreover, this method controls multicollinearity, leading to an optimal set of explanatory variables. PMID:29131829

Protein aggregation as bacterial inclusion bodies is reversible.

PubMed

Carrió, M M; Villaverde, A

2001-01-26

Inclusion bodies are refractile, intracellular protein aggregates usually observed in bacteria upon targeted gene overexpression. Since their occurrence has a major economical impact in protein production bio-processes, in vitro refolding strategies are under continuous exploration. In this work, we prove spontaneous in vivo release of both beta-galactosidase and P22 tailspike polypeptides from inclusion bodies resulting in their almost complete disintegration and in the concomitant appearance of soluble, properly folded native proteins with full biological activity. Since, in particular, the tailspike protein exhibits an unusually slow and complex folding pathway involving deep interdigitation of beta-sheet structures, its in vivo refolding indicates that bacterial inclusion body proteins are not collapsed into an irreversible unfolded state. Then, inclusion bodies can be observed as transient deposits of folding-prone polypeptides, resulting from an unbalanced equilibrium between in vivo protein precipitation and refolding that can be actively displaced by arresting protein synthesis. The observation that the formation of big inclusion bodies is reversible in vivo can be also relevant in the context of amyloid diseases, in which deposition of important amounts of aggregated protein initiates the pathogenic process.

Expression, characterization of a novel nitrilase PpL19 from Pseudomonas psychrotolerans with S-selectivity toward mandelonitrile present in active inclusion bodies.

PubMed

Sun, Huihui; Gao, Wenyuan; Wang, Hualei; Wei, Dongzhi

2016-03-01

To identify a novel nitrilase with S-selectivity toward mandelonitrile that can produce (S)-mandelic acid in one step. A novel nitrilase PpL19 from Pseudomonas psychrotolerans L19 was discovered by genome mining. It showed S-selectivity with an enantiomeric excess of 52.7 % when used to hydrolyse (R, S)-mandelonitrile. No byproduct was observed. PpL19 was overexpressed in Escherichia coli BL21 (DE3) and formed inclusion bodies that were active toward mandelonitrile and stable across a broad range of temperature and pH. In addition, PpL19 hydrolysed nitriles with diverse structures; arylacetonitriles were the optimal substrates. Homology modelling and docking studies of both enantiomers of mandelonitrile in the active site of nitrilase PpL19 shed light on the enantioselectivity. A novel nitrilase PpL19 from P. psychrotolerans L19 was mined and distinguished from other nitrilases as it was expressed as an active inclusion body and showed S-selectivity toward mandelonitrile.

Pyrvinium pamoate changes alternative splicing of the serotonin receptor 2C by influencing its RNA structure

PubMed Central

Shen, Manli; Bellaousov, Stanislav; Hiller, Michael; de La Grange, Pierre; Creamer, Trevor P.; Malina, Orit; Sperling, Ruth; Mathews, David H.; Stoilov, Peter; Stamm, Stefan

2013-01-01

The serotonin receptor 2C plays a central role in mood and appetite control. It undergoes pre-mRNA editing as well as alternative splicing. The RNA editing suggests that the pre-mRNA forms a stable secondary structure in vivo. To identify substances that promote alternative exons inclusion, we set up a high-throughput screen and identified pyrvinium pamoate as a drug-promoting exon inclusion without editing. Circular dichroism spectroscopy indicates that pyrvinium pamoate binds directly to the pre-mRNA and changes its structure. SHAPE (selective 2′-hydroxyl acylation analysed by primer extension) assays show that part of the regulated 5′-splice site forms intramolecular base pairs that are removed by this structural change, which likely allows splice site recognition and exon inclusion. Genome-wide analyses show that pyrvinium pamoate regulates >300 alternative exons that form secondary structures enriched in A–U base pairs. Our data demonstrate that alternative splicing of structured pre-mRNAs can be regulated by small molecules that directly bind to the RNA, which is reminiscent to an RNA riboswitch. PMID:23393189

Encapsulation of CO2 into amorphous alpha-cyclodextrin powder at different moisture contents - Part 2: Characterization of complexed powders and determination of crystalline structure.

PubMed

Ho, Thao M; Howes, Tony; Jack, Kevin S; Bhandari, Bhesh R

2016-09-01

This study aims to characterize CO2-α-cyclodextrin (α-CD) inclusion complexes produced from amorphous α-CD powder at moisture contents (MC) close to or higher than the critical level of crystallization (e.g. 13, 15 and 17% MC on wet basis, w.b.) at 0.4 and 1.6MPa pressure for 72h. The results of (13)C NMR, SEM, DSC and X-ray analyses showed that these MC levels were high enough to induce crystallization of CO2-α-CD complexed powders during encapsulation, by which amount of CO2 encapsulated by amorphous α-CD powder was significantly increased. The formation of inclusion complexes were well confirmed by results of FTIR and (13)C NMR analyses through an appearance of a peak associated with CO2 on the FTIR (2334cm(-1)) and NMR (125.3ppm) spectra. Determination of crystal packing patterns of CO2-α-CD complexed powders showed that during crystallization, α-CD molecules were arranged in cage-type structure in which CO2 molecules were entrapped in isolated cavities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Preparation and Characterization of Nanoparticle β-Cyclodextrin:Geraniol Inclusion Complexes.

PubMed

Hadian, Zahra; Maleki, Majedeh; Abdi, Khosro; Atyabi, Fatemeh; Mohammadi, Abdoreza; Khaksar, Ramin

2018-01-01

The aim of the present study was to formulate β-cyclodextrin (β-CD) nanoparticles loaded with geraniol (GR) essential oil (EO) with appropriate physicochemical properties. Complexation of GR with β-CD was optimized by evaluation of four formulations, using the co-precipitation method, and the encapsulation efficiency (EE), loading, size, particle size distribution (PDI) and zeta potential were investigated. Further characterization was performed with nuclear magnetic resonance spectroscopy ( 1 H NMR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and infra-red (IR) spectroscopy analysis. Results showed that the physicochemical properties of the nanoparticles were affected by GR content in formulations that yielded nanoscale-size particles ranging from 111 to 258 nm. The highest encapsulation efficiency (79.4 ± 5.4%) was obtained when the molar ratio of EO to β-CD was 0.44: 0.13 with negative zeta potential (-21.1 ± 0.5 mV). The 1 H-NMR spectrum confirmed the formation structure of the EO and β-CD nanoparticle complex. Complexation with geraniol resulted in changes of IR profile, NMR chemical shifts, DSC properties, and SEM of β-cyclodextrin. Inclusion complex of essential oil with β-cyclodextrin was considered as promising bioactive materials for designing functional food.