bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of protoberberine alkaloids in medicinal plants based on acidic potassium permanganate chemiluminescence system
Authors: Xu Xueqin , Lin Qiang , He Xiaoyan , Fu FengFu , Chen Guonan 
Published: September 2009

AbstractA simple method was established to determine protoberberine alkaloids in Cortex Phellodendri and Rhizoma Coptidis based on an acidic potassium permanganate chemiluminescence (CL) system. The optimum conditions for the CL reaction between protoberberine alkaloids and potassium permanganate were studied in detail. Under the optimum conditions, the linear response ranges for berberine, palmatine and jatrorrhizine were 0.038–7.27, 0.031–18.1 and 0.012–3.61 μg/mL with detection limits of 0.005, 0.004 and 0.0007 μg/mL, respectively. This method was successfully applied to determine the content of protoberberine alkaloids (calculated using berberine as an index) in Cortex Phellodendri and Rhizoma Coptidis. In addition, a possible mechanism of this CL reaction was proposed on the basis of the investigation of CL, UV and fluorescent spectra of protoberberine alkaloids in acidic solution containing potassium permanganate. Copyright © 2009 John Wiley & Sons, Ltd.
Resonance Rayleigh‐scattering spectral method for the determination of some aminoglycoside antibiotics using CdTe quantum dots as a probe
Authors: Wang Lei , Peng Juanjuan , Liu Zhengwen , He Youqiu 
Published: September 2009

AbstractA novel method is used for the determination of some aminoglycoside antibiotics (AGs) such as etimicin (ETM), isepamicin (ISP) and amikacin (AMK). It is based on the resonance Rayleigh scattering (RRS) intensities enhanced by AGs‐induced CdTe quantum dots aggregation. Under the optimum conditions, the increments in RRS intensity were directly proportional to the concentration of AGs in certain ranges. At the same time, the second‐order scattering, the frequency‐doubling scattering and the frequency‐trebling scattering intensities were also enhanced and their increments were proportional to the concentration of AGs. Among them, the RRS method had the highest sensitivity; the linear ranges and detection limits for ETM, ISP and AMK were 0.085–7.2, 0.0067–1.2, 0.017–6.0 and 0.025, 0.0051, 0.0020 μg mL−1. This method was applied to the measurement of AGs in human serum and urine with satisfactory results. In addition, the reaction mechanism and the reasons for the enhancement of RRS are discussed using fluorescence, RRS, transmission electron microscope technology and quantum chemistry method. Copyright © 2009 John Wiley & Sons, Ltd.
Medical and psychiatric problems among men and women in a community corrections residential setting
Authors: Gunter Tracy D. , Philibert Robert , Hollenbeck Nancy 
Published: September 2009

AbstractThough the medical and mental health morbidity of incarcerated offenders has been discussed in a number of recent reports, very few data have been published concerning medical and mental health problems facing those on community corrections supervision. In this study of community corrections offenders utilizing residential facilities, we found that frequencies of substance use disorders, other mental health disorders, and medical problems exceeded frequencies found in the community and, in some cases, were higher than frequencies found in incarcerated individuals. Of particular concern were the high frequencies of substance use disorders, traumatic brain injury, anxiety states, suicidal ideation, and prior self‐harm. While the level of self‐reported medical and mental health service utilization was higher than expected, it appeared low relative to the disease burden reported by this special population. We conclude that concurrent evaluation and treatment of medical and psychiatric problems during the process of community supervision is indicated in this population. Copyright © 2009 John Wiley & Sons, Ltd.
Malingering in a correctional setting: the use of the Structured Interview of Reported Symptoms in a jail sample
Authors: McDermott Barbara E. , Sokolov Gregory 
Published: September 2009

AbstractThe ability to detect malingering in the correctional setting is of paramount importance. The burgeoning jail and prison population combined with statutory requirements for the provision of mental health treatment require that only those most in need receive these services. Several structured assessments have been developed to assist in the identification of individuals more likely to be feigning psychiatric symptoms. Prior to the development of these specialized assessments, subscales of standard psychological tests were used as an indicator of assessment attitudes, for both malingering and other dissimulation. At the Sacramento County (CA) Jail, the Structured Interview of Reported Symptoms (SIRS) is routinely administered when clinicians feel there is a possibility that an inmate receiving psychiatric services may be feigning or exaggerating his/her symptoms. Our study examined data from these evaluations of inmates in conjunction with other clinical data (e.g., psychiatric diagnosis, educational level) to determine those factors most associated with malingering in jail inmates. Our results indicate that the prevalence of malingering in our sample was quite high: over 66% were found to be malingering based on the scoring criteria for the SIRS. Inmates diagnosed with Antisocial Personality Disorder were no more likely to feign symptoms than inmates without this diagnosis. Inmates designated as malingering in their charts were no more likely to be found malingering on the SIRS, suggesting that they may have adopted an effective strategy. Copyright © 2009 John Wiley & Sons, Ltd.
Structure‐Specific Recognition of Friedreich's Ataxia (GAA)n Repeats by Benzoquinoquinoxaline Derivatives
Authors: Bergquist Helen , Nikravesh Abbas , Fernández Raquel Domingo , Larsson Veronica , Nguyen Chi‐Hung , Good Liam , Zain Rula 
Published: September 2009

AbstractExpansion of GAA triplet repeats in intron 1 of the FXN gene reduces frataxin expression and causes Friedreich's ataxia. (GAA)n repeats form non‐B‐DNA structures, including triple helix H‐DNA and higher‐order structures (sticky DNA). In the proposed mechanisms of frataxin gene silencing, central unanswered questions involve the characterization of non‐B‐DNA structure(s) that are strongly suggested to play a role in frataxin expression. Here we examined (GAA)n binding by triplex‐stabilizing benzoquinoquinoxaline (BQQ) and the corresponding triplex‐DNA‐cleaving BQQ‐1,10‐phenanthroline (BQQ‐OP) compounds. We also examined the ability of these compounds to act as structural probes for H‐DNA formation within higher‐order structures at pathological frataxin sequences in plasmids. DNA‐complex‐formation analyses with a gel‐mobility‐shift assay and sequence‐specific probing of H‐DNA‐forming (GAA)n sequences by single‐strand oligonucleotides and triplex‐directed cleavage demonstrated that a parallel pyrimidine (rather than purine) triplex is the more stable motif formed at (GAA)n repeats under physiologically relevant conditions.
Selective Catalytic Hydrogenation of Functionalized Nitroarenes: An Update
Authors: Blaser Hans‐Ulrich , Steiner Heinz , Studer Martin 
Published: September 2009

AbstractIn this update, progress made in the last decade for the selective catalytic hydrogenation of nitroarenes in the presence of other reducible functions is reviewed. The main focus is on catalytic systems capable of reducing nitro groups with very high chemoselectivity in substrates containing carbon–carbon or carbon–nitrogen double or triple bonds, carbonyl or benzyl groups, and multiple Cl, Br, or I substituents. The performance of new catalyst types is described, most notably of gold‐based catalysts, but also of modified classical Pt, Pd, and Ni catalysts, as well as homogeneous catalysts. The best results for the various chemoselectivity problems are compiled and assessed with regard to their versatility and synthetic viability. In addition, progress in understanding mechanistic aspects are briefly described.
Highly Enhanced Phenol Hydroxylation in [h0h]‐Oriented Fe–ZSM‐5 Membranes
Authors: Lang Lin , Liu Xiufeng , Hu Mingliang , Zhang Baoquan 
Published: September 2009

AbstractCatechol (CAT) and hydroquinone (HQ) are two important diphenol isomers with a variety of industrial applications. The hydroxylation of phenol catalyzed by transition metal (TM) substituted ZSM‐5 is an environmentally benign route for diphenol production, which is usually governed by intracrystalline diffusion. Therefore, the availability of highly oriented TM‐ZSM‐5 membranes and their utilization in an interphase membrane reactor can significantly promote the hydroxylation of phenol. The continuous and [h0h]‐oriented Fe–ZSM‐5 membrane on the porous α‐Al2O3 was prepared using a new seeded growth method. Characterization was carried out by using SEM, XRD, UV/Vis, and EPMA techniques, which demonstrated that the [h0h]‐oriented membrane consists of Fe substituted ZSM‐5 crystal grains with an Si/Fe ratio of approximately 75. Compared with the catalytic performance of different sized Fe–ZSM‐5 grains loaded in the traditional slurry reactor, the [h0h]‐oriented Fe–ZSM‐5 membrane in the interphase membrane reactor showed significantly improved phenol conversion and selectivity for CAT and HQ due to the molecular path control in the zeolite membranes.
A Mechanism of Adsorption of β‐Nicotinamide Adenine Dinucleotide on Graphene Sheets: Experiment and Theory
Authors: Pumera Martin , Scipioni Roberto , Iwai Hideo , Ohno Takahisa , Miyahara Yuji , Boero Mauro 
Published: September 2009

Abstractβ‐Nicotinamide adenine dinucleotide (NAD+) and its reduced form (NADH) play major roles in the development of electrochemical enzyme biosensors and biofuel cells. Unfortunately, the oxidation of NADH at carbon electrodes suffers from passivation of the electrodes and a decrease in passing currents. Here, we investigate experimentally and theoretically the reasons for such passivation. High‐resolution X‐ray photoelectron spectroscopy (HR‐XPS), voltammetry, and amperometry show that adsorption occurs on the edges and “edge‐like” defects of graphene sheets. HR‐XPS and ab initio molecular dynamics show that the adsorption of NAD+ molecules on the edges of graphene happens due to interaction with oxygen‐containing groups such as carboxylic groups, while graphene edges substituted only with hydrogen are prone to passivation.
Oxidative Interception of the Hydroamination Pathway: A Gold‐Catalyzed Diamination of Alkenes
Authors: Iglesias Alvaro , Muñiz Kilian 
Published: September 2009

AbstractA complimentary diamination of alkenes by using homogeneous gold catalysts is described. The reaction is one of very few examples of homogeneous gold oxidation catalysis and proceeds with high selectivity under mild conditions. Individual steps of the suggested catalytic cycle were investigated on isolated model gold complexes, and new pathways for gold‐catalyzed amination reactions were established. The key step is an intramolecular alkyl–nitrogen bond formation from a gold(III) intermediate. This process validates the concept of reductive elimination from high oxidation catalyst states for this type of CN bond forming reactions.
High‐Affinity Inhibitors of tRNA‐Guanine Transglycosylase Replacing the Function of a Structural Water Cluster
Authors: Kohler Philipp C. , Ritschel Tina , Schweizer W. Bernd , Klebe Gerhard , Diederich François 
Published: September 2009

AbstractThe tRNA‐modifying enzyme tRNA–guanine transglycosylase (TGT) is essential for the pathogenic mechanism of Shigella flexneri, the causing agent of the bacterial diarrheal disease shigellosis. Herein, the synthesis of a new class of rationally designed 6‐amino‐imidazo[4,5‐g]quinazolin‐8(7H)‐one‐ (lin‐benzoguanine) based inhibitors of TGT are reported. In order to accommodate a small hydrophobic crevice opening near the binding site of ribose‐34, 2‐aminoethyl substituents were introduced in position 4 of the heterocyclic scaffold. For this purpose, a synthetic sequence consisting of iodination, Suzuki cross‐coupling, hydroboration, Mitsunobu reaction, and Gabriel synthesis was employed, furnishing a primary amine that served as a common intermediate for the preparation of a series of derivatives. The resulting ligands displayed very low inhibition constants, down to Ki=2 nM. Substantial additional inhibitory potency is gained by interaction of terminal lipophilic groups attached to the substituent at position 4 with the hydrophobic crevice shaped by Val45 and Leu68. At the same time, the secondary ammonium center in the substituent displaces a cluster of water molecules, solvating the catalytic residues Asp102 and Asp280, without loss in binding affinity. In addition, a synthetic intermediate with an unusual 3,6,7,8,9,10‐hexahydroimidazo[4,5‐g][1,3]benzodiazepine core, as confirmed by X‐ray analysis, is reported.
Vinylation of Nitro‐Substituted Indoles, Quinolinones, and Anilides with Grignard Reagents
Authors: Egris Riccardo , Villacampa Mercedes , Menéndez J. Carlos 
Published: September 2009

AbstractThe reaction of vinyl Grignard reagents with o‐methoxynitroarenes containing an electron‐releasing substituent para to the nitro group proceeds through a pathway that is different from the initially expected Bartoli indole synthesis. Thus, instead of giving fused indole derivatives, these reactions provide a very mild and efficient new procedure for the synthesis of synthetically relevant aromatic systems containing an o‐nitrovinyl moiety, such as 5‐nitro‐4‐vinylindoles, 6‐nitro‐7‐vinylindoles, 6‐nitro‐5‐vinyl‐2(1H)quinolinones, and 4‐nitro‐3‐vinylanilines.
Azoles as Reactive Nucleophiles with Cyclic Perfluoroalkenes
Authors: Garg Sonali , Twamley Brendan , Zeng Zhuo , Shreeve Jean'ne M. 
Published: September 2009

AbstractDi‐ and multiazole‐substituted fluorocyclic products (2–13) were readily synthesized in good to high yields. These were synthesized by nucleophilic substitution reactions of perfluorocycloalkenes with azoles (i.e., imidazole, triazole) involving simple reaction procedures. Interestingly, these azoles were later found to be reactive not only with the vinylic, but also with the allylic fluorine atoms. This resulted in the substitution of up to six azoles on the fluorinated rings. Stoichiometry plays a key role in determining the degree of substitution. For comparison, the analogous reactions of N‐substituted 1‐(trimethylsilyl)‐imidazole and 1‐(trimethylsilyl)‐1,2,4‐triazole were also investigated. All of the new compounds were fully characterized by elemental, spectral (19F, 1H, 13C NMR), and thermal differential scanning calorimetry (DSC) analyses.
Studies on the Synthesis and Activity of Three Tripalladium Complexes Containing Planaramine Ligands
Authors: Farhad Mohammad , Yu Jun Qing , Beale Philip , Fisher Keith , Huq Fazlul 
Published: September 2009

AbstractThe present study deals with the synthesis, characterization and activity against human cancer cell lines: A2780, A2780cisR and A2780ZD0473R of three tripalladium complexes, MH3, MH4 and MH5, that each have two planaramine ligands bound to the central metal ion. Cellular uptake levels, extent of DNA binding, and nature of interaction with salmon sperm and pBR322 plasmid DNA were determined for each complex. Palladium compounds are much more reactive than their corresponding platinum derivatives, which makes them therapeutically inactive but toxic. However, the results of the present study suggest that significant antitumour activity can be introduced in palladium complexes by lessening their reactivity by the introduction of sterically hindered ligands such as 2‐hydroxypyridine, 3‐hydroxypyridine and 4‐hydroxypyridine. When bound to the central palladium ion, 4‐hydroxypyridine appears to be more activating than 2‐hydroxypyridine and 3‐hydroxypyridine, suggesting that noncovalent interactions, such as hydrogen bonding, may also be key determinants of antitumour activity in addition to the steric effect. While cisplatin binds with DNA to form intrastrand GG adducts that causes local bending of a DNA strand, these planaramine‐derived palladium complexes are expected to bind with DNA and form a number of long‐range interstrand GG adducts that would cause a global change in DNA conformation, provided the tripalladium cations in MH3, MH4 and MH5 persist under physiological conditions.
Ionic Association of the Ionic Liquids [C4mim][BF4], [C4mim][PF6], and [Cnmim]Br in Molecular Solvents
Authors: Wang Huiyong , Wang Jianji , Zhang Sheli , Pei Yuanchao , Zhuo Kelei 
Published: September 2009

AbstractConsidering the ionic nature of ionic liquids (ILs), ionic association is expected to be essential in solutions of ILs and to have an important influence on their applications. Although numerous studies have been reported for the ionic association behavior of ILs in solution, quantitative results are quite scarce. Herein, the conductivities of the ILs [Cnmim]Br (n=4, 6, 8, 10, 12), [C4mim][BF4], and [C4mim][PF6] in various molecular solvents (water, methanol, 1‐propanol, 1‐pentanol, acetonitrile, and acetone) are determined at 298.15 K as a function of IL concentration. The conductance data are analyzed by the Lee–Wheaton conductivity equation in terms of the ionic association constant (KA) and the limiting molar conductance (Λm0). Combined with the values for the Br− anion reported in the literature, the limiting molar conductivities and the transference numbers of the cations and [BF4]− and [PF6]− anions are calculated in the molecular solvents. It is shown that the alkyl chain length of the cations and type of anion affect the ionic association constants and limiting molar conductivities of the ILs. For a given anion (Br−), the Λm0 values decrease with increasing alkyl chain length of the cations in all the molecular solvents, whereas the KA values of the ILs decrease in organic solvents but increase in water as the alkyl chain length of the cations increases. For the [C4mim]+ cation, the limiting molar conductivities of the ILs decrease in the order Br−>[BF4]−>[PF6]−, and their ionic association constants follow the order [BF4]−>[PF6]−>Br− in water, acetone, and acetonitrile. Furthermore, and similar to the classical electrolytes, a linear relationship is observed between ln KA of the ILs and the reciprocal of the dielectric constants of the molecular solvents. The ILs are solvated to a different extent by the molecular solvents, and ionic association is affected significantly by ionic solvation. This information is expected to be useful for the modulation of the IL conductance by the alkyl chain length of the cations, type of anion, and physical properties of the molecular solvents.
Use of flow cytometry as a quality control device for liquid‐based cervical cytology specimens
Authors: Kottaridi Christine , Georgoulakis John , Kassanos Dimitrios , Pappas Asimakis , Spathis Aris , Margari Niki , Aninos Dionissios , Karakitsos Petros 
Published: September 2009

AbstractBackground:Cervical cancer is the second most common cancer in women worldwide comprising a major concern of public health. Liquid‐based cytology provides significantly more effective detection of low‐grade intraepithelial neoplasia or more severe lesions, without loss of diagnostic specificity and reduces the number of cases classified as unsatisfactory. The objective of the study is the evaluation of flow cytometry as a rapid tool for quality control of the liquid specimen adequacy for the purpose of precise cytological diagnosis in detecting cervical abnormalities.Methods:A total of 1,854 women undergoing routine cervical cytology joined this cohort study. A monolayer smear was prepared and 1 ml aliquot was removed and prepared for flow cytometric analysis. Cells were fixed and run on a Partec CyFlow SL, with front scatter (FSS) and side scatter (SSC) set on logarithmic scale. The forward scatter versus side scatter dot‐plot was used for the distinction of ectocervical, endocervical, and polymorphonuclear cells.Results:In the total of 1,854 cases, 15 specimens (0.8%) were characterized by the cytopathologist as unsatisfactory. Inadequacy was confirmed by flow cytometric analysis for four samples. Monolayer smears were reprepared for the remaining 11 samples. After the second microscopic observation, six out of the 11 cases (54.5%) were found to be satisfactory, whereas the remaining five were still designated as unsatisfactory by the cytopathologist.Conclusion:The parallel screening of adequacy by quantification of cell populations with flow cytometry can serve as an internal control for diagnosis and can overall decrease the number of unsatisfactory samples. © 2009 Clinical Cytometry Society
Chains of Alkaline Metal Cations and Tetracyanidoborato Anions – Syntheses, Structures and Properties of the New [AI(18‐crown‐6)][B(CN)4)] (AI = Cs, Rb)
Authors: Bernsdorf Arne , Köckerling Martin 
Published: September 2009

Abstract[Cs(18‐crown‐6)][B(CN)4] and [Rb(18‐crown‐6)][B(CN)4] can be obtained as colourless transparent crystals by slow evaporation of the solvent of aqueous solutions of these compounds. Both substances crystallise in the monoclinic crystal system; [Cs(18‐crown‐6)][B(CN)4]: C2/c, a = 13.819(1), b = 15.841(1), c = 10.1717(7) Å, β = 92.117(4)°, V = 2225.0(3) Å3, Z = 4; [Rb(18‐crown‐6)][B(CN)4]: P21/n, a = 14.237(2), b = 9.455(1), c = 15.942(2) Å, β = 94.319(4)°, V = 2139.9(5) Å3, Z = 4. These compounds are characterised by unprecedented linear coordination chains. Double rows of alkaline metal cations, encapsulated in 18‐crown‐6 ether molecules, which are oriented approximately face‐to‐face, are interconnected by tetracyanidoborato anions. Nevertheless, the connectivity differs significantly between the two compounds. In the Cs compound the [B(CN)4]− anions are tetrafunctional with two CN groups coordinating in a chelate‐type mode to one Cs cation, whereas the other two CN groups bridge two neighbouring Cs cations of the opposite row of [Cs(18‐crown‐6)]+ units. In the Rb compound only two of the four CN groups are bonded to the cations, the other two are uncoordinated. The bonded CN groups bridge between two Rb cations of opposite rows. These two compounds show that the[B(CN)4]− anion has a tremendous variability of coordination modes. Not only can 3D network structures be formed by using [B(CN)4]− anionic units but also low‐dimensional structures, as shown by these two new compounds. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
NHTS: A Hollow, Noble‐Metal‐Modified Titanium Silicalite
Authors: Shi Chunfeng , Zhu Bin , Lin Min , Long Jun 
Published: September 2009

AbstractThe major drawback of direct oxidation technology (onsite hydrogen peroxide production followed by its conversion into organic oxides without refining) is the design and preparation of the bifunctional catalysts used therein. Herein we present a bifunctional catalytic material (NHTS), which is synthesized by a revised semi‐in‐situ method that allows a noble metal to be distributed throughout the titanosilicate framework and also results in a redistribution of active Ti species throughout the crystals, thereby enriching the surface of the hollow crystals with catalytic species. This compound has been characterized by various techniques and its activity and selectivity for the direct epoxidation of propylene investigated. The results indicate that NHTS shows a very ordered MFI topology, with the noble metal incorporated in the framework, and a hollow structure, which makes it a good alternative for catalytic oxidations. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)