bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seasonal and Geographical Influences on the Chemical Composition of Juniperus phoenicea L. Essential Oil Leaves from the Northern Tunisia
Authors: Medini Hanene , Elaissi Ameur , Farhat Farhat , Khouja Mohamed Larbi , Chemli Rachid , Harzallah‐Skhiri Fathia 
Published: September 2009

AbstractThe essential‐oil composition of 60 individual trees of Juniperus phoenicea L. from four Tunisian populations in three different periods were investigated by GC and GC/MS analyses. 59 Compounds were identified in the oils, and a relatively high variation in their contents was found. All the oils were dominated by the terpenic hydrocarbon fraction, and the main component was α‐pinene (20.28–40.86%). The results of the oil compositions were processed by hierarchical clustering and principal component analysis (PCA) allowing establishing four groups of essential‐oils differentiated by one compound or more. Pattern of geographic variation in essential‐oil composition indicated that individuals from the continental site (Makthar) were clearly distinguished from those from littoral localities (Tabarka, Hawaria, and Rimel).
Immunosuppressive Withanolides from Withania coagulans
Authors: Huang Chao‐Feng , Ma Lei , Sun Li‐Juan , Ali Mumtaz , Arfan Mohammad , Liu Jian‐Wen , Hu Li‐Hong 
Published: September 2009

AbstractSix new withanolides, withacoagulins A–F (1–6, resp.), together with ten known withanolides, 7–16, were isolated from the aerial parts of Withania coagulans. Their structures were determined by spectroscopic techniques including 1D‐ and 2D‐NMR (1H, 13C, HMQC, and HMBC) and MS experiments. These compounds, including the crude extracts of this herb, exhibited strong inhibitory activities on the T‐ and B‐cell proliferation.
Structural Variations and Molecular Dynamics of Rare‐Earth Metal Complexes with the N,N‐Bis(2‐{pyrid‐2‐yl}ethyl)hydroxylaminato Ligand
Authors: Hellmann Benjamin J. , Venugopal Ajay , Mix Andreas , Neumann Beate , Stammler Hans‐Georg , Willner Alexander , Pape Tanja , Hepp Alexander , Mitzel Norbert W. 
Published: September 2009

AbstractThe reaction of the donor‐functionalised N,N‐bis(2‐{pyrid‐2‐yl}ethyl)hydroxylamine and [LnCp3] (Cp=cyclopentadiene) resulted in the formation of bis(cyclopentadienyl) hydroxylaminato rare‐earth metal complexes of the general constitution [Ln(C5H5)2{ON(C2H4‐o‐Py)2}] (Py= pyridyl) with Ln=Lu (1), Y (2), Ho (3), Sm (4), Nd (5), Pr (6), La (7). These compounds were characterised by elemental analysis, mass spectrometry, NMR spectroscopy (for compounds 1, 2, 4 and 7) and single‐crystal X‐ray diffraction experiments. The complexes exhibit three different aggregation modes and binding motifs in the solid state. The late rare‐earth metal atoms (Lu, Y, Ho and Sm) form monomeric complexes of the formula [Ln(C5H5)2{η2‐ON(C2H4‐η1‐o‐Py)(C2H4‐o‐Py)}] (1–4, respectively), in which one of the pyridyl nitrogen donor atoms is bonded to the metal atom in addition to the side‐on coordinating hydroxylaminato unit. The larger Nd3+ and Pr3+ ions in 5 and 6 make the hydroxylaminato unit capable of dimerising through the oxygen atoms. This leads to the dimeric complexes [(Ln(C5H5)2{μ‐η1:η2‐ON(C2H4‐o‐Py)2})2] without metal–pyridine bonds. Compound 7 exhibits a dimeric coordination mode similar to the complexes 5 and 6, but, in addition, two pyridyl functions coordinate to the lanthanum atoms leading to the [(La(C5H5)2{ON(C2H4‐o‐Py)}{μ‐η1:η2‐ON(C2H4‐η1‐o‐Py)})2] complex. The aggregation trend is directly related to the size of the metal ions. The complexes with coordinative pyridine–metal bonds show highly dynamic behaviour in solution. The two pyridine nitrogen atoms rapidly change their coordination to the metal atom at ambient temperature. Variable‐temperature (VT) NMR experiments showed that this dynamic exchange can be frozen on the NMR timescale.
Metal–Organic Perovskites: Synthesis, Structures, and Magnetic Properties of [C(NH2)3][MII(HCOO)3] (M=Mn, Fe, Co, Ni, Cu, and Zn; C(NH2)3= Guanidinium)
Authors: Hu Ke‐Li , Kurmoo Mohamedally , Wang Zheming , Gao Song 
Published: September 2009

AbstractWe report the synthesis, crystal structures, and spectral, thermal, and magnetic properties of a family of metal–organic perovskite ABX3, [C(NH2)3][MII(HCOO)3], in which A=C(NH2)3 is guanidinium, B=M is a divalent metal ion (Mn, Fe, Co, Ni, Cu, or Zn), and X is the formate HCOO−. The compounds could be synthesized by either diffusion or hydrothermal methods from water or water‐rich solutions depending on the metal. The five members (Mn, Fe, Co, Ni, and Zn) are isostructural and crystallize in the orthorhombic space group Pnna, while the Cu member in Pna21. In the perovskite structures, the octahedrally coordinated metal ions are connected by the anti–anti formate bridges, thus forming the anionic NaCl‐type [M(HCOO)3]− frameworks, with the guanidinium in the nearly cubic cavities of the frameworks. The Jahn–Teller effect of Cu2+ results in a distorted anionic Cu–formate framework that can be regarded as Cu–formate chains through short basal CuO bonds linked by the long axial CuO bonds. These materials show higher thermal stability than other metal–organic perovskite series of [AmineH][M(HCOO)3] templated by the organic monoammonium cations (AmineH+) as a result of the stronger hydrogen bonding between guanidinium and the formate of the framework. A magnetic study revealed that the five magnetic members (except Zn) display spin‐canted antiferromagnetism, with a Néel temperature of 8.8 (Mn), 10.0 (Fe), 14.2 (Co), 34.2 (Ni), and 4.6 K (Cu). In addition to the general spin‐canted antiferromagnetism, the Fe compound shows two isothermal transformations (a spin‐flop and a spin‐flip to the paramagnetic phase) within 50 kOe. The Co member possesses quite a large canting angle. The Cu member is a magnetic system with low dimensional character and shows slow magnetic relaxation that probably results from the domain dynamics.
A DFT‐Based Analysis of the Grossly Varying Reactivity Pattern in Room‐Temperature Activation and Dehydrogenation of CH4 by Main‐Group Atomic M+ (M=Ga, Ge, As, and Se)
Authors: Zhang Xinhao , Schwarz Helmut 
Published: September 2009

AbstractInsight into the mechanism(s) of the recently reported thermal reactions of methane with the main‐group atomic cations Ga+, Ge+, As+ and Se+ (A. Shayesteh et al. J. Phys. Chem. A 2009, 113, 5602) has been obtained from DFT‐based calculations including relativistic effects. Excellent agreement with the experimental findings has been achieved, and a coherent description of the reactivity is provided. For example, the chemical inertness of the Ga+/CH4 couple is due to an endergonic formation of an encounter complex as well as a high endothermicity for the dehydrogenation of methane (ΔG298=84.7 kcal mol−1). For Ge+/CH4, formation of an encounter complex is slightly exergonic (ΔG298=−8.9 kcal mol−1) and thus is observed with low efficiency; the dehydrogenation path, however, is not accessible (ΔG298=13.6 kcal mol−1). For the Se+/CH4 couple, the significantly enhanced rate of adduct formation is suggested to result from a spin–orbit‐mediated quartet–doublet spin flip that generates the insertion product [(H)Se(CH3)]+, 2Se‐3, in its doublet state rather than forming a simple encounter complex. For the dehydrogenation of 2Se‐3 to generate 2[Se(CH2)]+, various mechanistic variants have been explored, all of which, however, involve transition structures that are located energetically above the entrance channel, thus preventing the reaction from occurring. In contrast, facile and efficient dehydrogenation of CH4 by ground‐state As+ (3P0) takes place, and this reaction constitutes a textbook example of the operation of a two‐state reactivity scenario. Here, a triplet–singlet conversion occurs along the oxidative insertion of As+ into the CH bond of CH4 to generate [(H)As(CH3)]+ in its singlet state. From this intermediate, which constitutes the global minimum on the As+/CH4 potential energy surface, dehydrogenation is brought about by a sequence of α‐hydrogen migration and reductive elimination of molecular hydrogen from the hydride carbene complex 1As‐5. The potential energy surfaces for the As+/CH4 couple are remarkably similar irrespective of including or ignoring relativistic effects in the calculations.
Microwave‐Assisted Cross‐Coupling and Hydrogenation Chemistry by Using Heterogeneous Transition‐Metal Catalysts: An Evaluation of the Role of Selective Catalyst Heating
Authors: Irfan Muhammed , Fuchs Michael , Glasnov Toma N. , Kappe C. Oliver 
Published: September 2009

AbstractThe concept of specific microwave effects in solid/liquid catalytic processes resulting from the selective heating of a microwave‐absorbing heterogeneous transition‐metal catalyst by using 2.45 GHz microwave irradiation was evaluated. As model transformations Ni/C‐, Cu/C‐, Pd/C‐, and Pd/Al2O3‐catalyzed carbon–carbon/carbon–heteroatom cross‐couplings and hydrogenation reactions were investigated. To probe the existence of specific microwave effects by means of selective catalyst heating in these transformations, control experiments comparing microwave dielectric heating and conventional thermal heating at the same reaction temperature were performed. Although the supported metal catalysts were experimentally found to be strongly microwave absorbing, for all chemistry examples investigated herein no differences in reaction rate or selectivity between microwave and conventional heating experiments under carefully controlled conditions were observed. This was true also for reactions that use low‐absorbing or microwave transparent solvents, and was independent of the microwave absorbtivity of the catalyst support material. In the case of hydrogenation reactions, the stirring speed was found to be a critical factor on the mass transfer between gas and liquid phase, influencing the rate of the hydrogenation in both microwave and conventionally heated experiments.
Synthesis of Modified 4H‐1,2,4‐Benzothiadiazine‐1,1‐dioxides and Determination of their Affinity and Selectivity for Different Types of KATPChannels
Authors: Lachenicht Stefan , Fischer Andreas , Schmidt Claas , Winkler Marcus , Rood Achim , Lemoine Horst , Braun Manfred 
Published: September 2009

Abstract4H‐1,2,4‐Benzothiadiazine‐1,1‐dioxides with various substituents in positions 3, 5, and 7 were synthesized and tested as KATPchannel agonists in artificial cell systems (CHO cells transfected with SUR1/Kir6.2, and HEK 293 transfected with SUR2B/Kir6.1) as model systems for insulin‐secreting pancreatic β‐cells and for smooth muscle cells, respectively. The effects of agonists were tested in intact cells using DiBAC4(3) [bis‐(1,3‐dibarbituric acid)trimethine oxanol] as a membrane potential dye, and the results compared with their binding affinity for the SUR2B‐type KATPchannels using the radioligand [3H]P1075. Compounds with cycloalkyl and (cycloalkyl)methyl side chains in position 3 had higher affinities towards the SUR2B/Kir6.1 receptor compared with the parent compound diazoxide (1 a). Compounds with bulky, nonpolar residues in position 3 exhibited remarkable selectivity for SUR2B‐type KATPchannels. The compound substituted with a bulky (1‐adamantyl)methyl residue exhibited micromolar affinity and activity on SUR2B‐type KATPchannels without being able to activate the SUR1‐type KATPchannels.
Is anti‐doping analysis so far from clinical, legal or forensic targets?: The added value of close relationships between related disciplines
Authors: Segura Jordi 
Published: September 2009

AbstractThere are many areas of common interest between anti‐doping laboratories and those working in the clinical, legal and forensic fields. In addition to methodological similarities, there are aspects of the findings in sport drug testing that overlap with other fields in such a way that sport drug testing and clinical, legal or forensic work may benefit from mutual interaction. Three recent examples are presented from the author's experience. Case report 1 concerns the clinical relevance of hCG findings in sport drug testing as potential indicators of the presence of a (testicular) tumour in athletes. Case report 2 refers to difficulties that accredited laboratories can encounter due to differences between national legal systems and the administrative regulation systems of sport authorities. The example involves a network of blood collection for further autologous transfusion. Case report 3 relates to additional forensic‐type investigations needed to interpret a situation where intoxication of a whole delegation was responsible for apparent doping cases. Clinical, legal and forensic fields must recognize the added value that some results and developments coming from anti‐doping laboratories may have. At the same time anti‐doping analysts should be aware of new issues, methodologies and problems appearing in related fields. Copyright © 2009 John Wiley & Sons, Ltd.
Total Synthesis of Phenanthro‐Quinolizidine Alkaloids: (±)‐Cryptopleurine, (±)‐Boehmeriasin A, (±)‐Boehmeriasin B and (±)‐Hydroxycryptopleurine
Authors: Cui Mingbo , Wang Qingmin 
Published: September 2009

AbstractThe first synthesis of (±)‐boehmeriasin A and B and a concise synthesis of (±)‐cryptopleurine and (±)‐hydroxycryptopleurine are described. The piperidine ring of these alkaloids was constructed by the coupling of the phenanthrene ring with 2‐bromopyridine through a nucleophilic substitution reaction and subsequent reduction of the resulting pyridyl ketone. The first crystal structure of a phenanthro‐quinolizidine alkaloid is also reported. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Thermal Rearrangements of Monoterpenes and Monoterpenoids
Authors: Stolle Achim , Ondruschka Bernd , Hopf Henning 
Published: September 2009

AbstractThe thermal conversions of monoterpenes and monoterpenoids are an interesting field of research with respect to mechanistic, kinetic, and theoretical issues. Since the beginning of the 20th century, these reactions have attracted the interest of many research groups, and even today there are sufficient problems and questions to deal with. This review covers the thermal isomerization chemistry of pinanes, pinenes, carenes, and thujenes over the past 70 years. Categorization of these compounds into groups, each of them being represented by a small parent molecule (cyclobutane, vinylcyclobutane, vinylcyclopropane), allows systematization of multitude of publications.
Synthesis of Deuterium‐Labeled Perfume Ingredients as Internal Standards for Their GC/MS Quantification
Authors: Chapuis Christian , Cantatore Carole , Fankhauser Peter , Challand René , Riedhauser Jean‐Jacques 
Published: September 2009

AbstractThe synthesis of various D‐labeled perfume ingredients (orris‐like, sandalwood‐like, musky, and amber‐like) is presented. These substances, possessing practically identical H2O/solid and solid/gas partition coefficients as their unlabeled analogues, are used as internal standards for the validation of a new analytical GC/MS method for the determination of low residual concentrations in H2O after biodegradability tests.
The heat transfer heterogeneities of bends in flow boiling of hairpin tubes
Authors: Meng Meng , Peng Xiao‐Feng 
Published: September 2009

AbstractA series of visual experiments were conducted for liquid– vapor two‐phase flow in hairpin tubes, and it was observed that most of the nucleation sites were located at the outer tube wall of the bend. From the simulation, it was concluded that the uneven velocity distribution in the bend induced the heat transfer heterogeneity. Furthermore, the nucleation of both the inner and outer tube wall of the bend and the wall temperature distribution were discussed to understand the physical phenomena. © 2009 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20269
Oxidative status in iron‐deficiency anemia
Authors: Yoo Jong‐Ha , Maeng Ho‐Young , Sun Young‐Kyu , Kim Young‐Ah , Park Dong‐Wook , Park Tae Sung , Lee Seung Tae , Choi Jong‐Rak 
Published: September 2009

AbstractOxidative stress is an imbalance between free radicals and antioxidant molecules that can play an important role in the pathogenesis of iron‐deficiency anemia (IDA). The aim of this study was to investigate oxidative status in patients with IDA and alteration of oxidative status after iron treatment. Thirty‐three female patients with IDA and 25 healthy controls were included in this study. Oxidant and total antioxidant capacity were determined using free oxygen radicals test and free oxygen radicals defence (Form CR 3000, Callegari, Parma, Italy). Catalase activity was measured by spectrophotometer using a commercially available kit (Bioxytech Catalase‐520, OxisResearch, Portland, OR). Oxidant activity in patients with IDA was significantly higher than controls (P<0.05), while total antioxidant and catalase activity were significantly lower (P<0.05). After treatment, oxidant, antioxidant, and catalase activity reached the levels of the control group, and no significant differences were observed among groups (P>0.05). In conclusion, our data indicate that blood reactive oxygen species was lower and total antioxidant and catalase activity were higher after rather than before treatment in patients with IDA. The results of our study support the higher oxidative stress hypothesis in IDA; however, due to the limited number of cases included, more studies may be required to confirm the results. J. Clin. Lab. Anal. 23:319–323, 2009. © 2009 Wiley‐Liss, Inc.
Correlation between Etest®, disk diffusion, and microdilution methods for antifungal susceptibility testing of Candida species from infection and colonization
Authors: Negri Melyssa , Henriques Mariana , Svidzinski Terezinha I.E. , Paula Claudete Rodrigues , Oliveira Rosário 
Published: September 2009

AbstractThe correlation between the microdilution (MD), Etest® (ET), and disk diffusion (DD) methods was determined for amphotericin B, itraconazole and fluconazole. The minimal inhibitory concentration (MIC) of those antifungal agents was established for a total of 70 Candida spp. isolates from colonization and infection. The species distribution was: Candida albicans (n=27), C. tropicalis (n=17), C. glabrata (n=16), C. parapsilosis (n=8), and C. lusitaniae (n=2). Non‐Candida albicans Candida species showed higher MICs for the three antifungal agents when compared with C. albicans isolates. The overall concordance (based on the MIC value obtainedwithin two dilutions) between the ET and the MD method was 83% for amphotericin B, 63% for itraconazole, and 64% for fluconazole. Considering the breakpoint, the agreement between the DD and MD methods was 71% for itraconazole and 67% for fluconazole. The DD zone diameters are highly reproducible and correlate well with the MD method, making agar‐based methods a viable alternative to MD for susceptibility testing. However, data on agar‐based tests for itraconazole and amphotericin B are yet scarce. Thus, further research must still be carried out to ensure the standardization to other antifungal agents. J. Clin. Lab. Anal. 23:324–330, 2009. © 2009 Wiley‐Liss, Inc.
Evaluation of DPC immulite 2000®Toxoplasma quantitative IgG/IgM kits for automated toxoplasmosis serology with immulite 2000®
Authors: Robert‐Gangneux Florence , Bourhis Chantal , Chevrier Sylviane , Gangneux Jean‐Pierre 
Published: September 2009

AbstractIn this study, we evaluated a new immunoassay for the automated detection of anti‐toxoplasma IgG and IgM with Immulite 2000® (DPC‐Siemens, La Garenne‐Colombes, France). We tested 280 sera from 112 patients with past infection (PI), 40 PI with residual IgM, 75 seronegatives, 16 infants (31 sera) monitored for neonatal screening of congenital toxoplasmosis, and 13 patients with recent seroconversion (SC) (22 sequential sera). Detection sensitivity and specificity for IgG were 99 and 100%, respectively. IgG titers obtained with Immulite 2000® were higher than with Vidas® (BioMérieux, Marcy I'Etoile, France) and Access® (Beckman‐Coulter, Villepinte, France) (paired Wilcoxon test z=4.44 and z=3.67, respectively, P<0.001). IgM specificity was 100%. Detection sensitivity for IgM was 100% in the SC group, 86% in congenitally infected infants, and 75% in PI with persistent IgM. IgM detection seemed less prolonged in time than with the IgM Access® and ISAGA® IgM techniques. J. Clin. Lab. Anal. 23:336–340, 2009. © 2009 Wiley‐Liss, Inc.
Epstein–Barr virus BZLF1 gene promoter variants in pediatric patients with acute infectious mononucleosis: Its comparison with pediatric lymphomas
Authors: Lorenzetti Mario Alejandro , Gutiérrez Marina Inés , Altcheh Jaime , Moscatelli Guillermo , Moroni Samanta , Chabay Paola Andrea , Preciado María Victoria 
Published: September 2009

AbstractEpstein–Barr virus genotypes can be distinguished by polymorphic variations in the genes encoding EBNA2, 3A, 3B, and 3C. The immediate early gene BZLF1 plays a key role in modulating the switch from latency to lytic replication and therefore enabling viral propagation. The aim of this study was to investigate and compare BZLF1 promoter sequence (Zp) variation in pediatric infectious mononucleosis (IM) and in pediatric EBV positive lymphoma biopsies. Zp was sequenced from peripheral blood mononuclear cells (PBMC) and throat swabs from 10 patients with IM at the time of diagnosis (D0) and during convalescence; and from 13 lymphoma biopsies. Zp − P and Zp − V3 variants were found in eight and one IM patients, as well as in five and six tumor biopsies, respectively. A correlation between viral genotype and Zp variant was found significant for Zp − V3 and EBV2 (P = 0.0002). One IM patient harbored two concomitant Zp variants. Regardless of anatomical compartment or stage of disease all IM patients displayed the same Zp variant along the course of the study. No new infections or adaptative selection of different variants was evidenced. A new Zp variant (Zp − V3 + 49) was described in two Hodgkin lymphomas, but not in IM. This is the first study to describe Zp variants compartmentalization in children with acute EBV infection and convalescence in a developing country; and comparing them with Zp variants in pediatric lymphomas from the same geographic area. J. Med. Virol. 81:1912–1917, 2009. © 2009 Wiley‐Liss, Inc.
Alterations in calcium signaling and a decrease in Bcl‐2 expression: Possible correlation with apoptosis in aged striatum
Authors: Ureshino R.P. , Bertoncini C.R. , Fernandes M.J.S. , Abdalla F.M.F. , Porto C.S. , Hsu Y.‐T. , Lopes G.S. , Smaili S.S. 
Published: September 2009

AbstractAging is a multifaceted process associated with various functional and structural deficits that might be evolved in degenerative diseases. It has been shown that neurodegenerative disorders are associated with alterations in Ca2+ homeostasis. Thus, in the present work, we have investigated Ca2+ signaling and apoptosis in aged striatum. Our results show that glutamate and NMDA evoke a greater Ca2+ rise in striatum slices from aged animals. However, this difference is not present when glutamate is tested in the absence of external Ca2+. Immunostaining of glutamate receptors shows that only NMDA receptors (NR1) are increased in the striatum of aged rats. Increases in mitochondrial Ca2+ content and in the reactive oxygen species levels were also observed in aged animals, which could be associated with tissue vulnerability. In addition, a decrease in the Bcl‐2 protein expression and an enhancement in apoptosis were also present in aged striatum. Together the results indicate that, in aged animals, alterations in Ca2+ handling coupled to an increase in ROS accumulation and a decrease in the prosurvival protein Bcl‐2 may contribute to apoptosis induction and cell death in rat striatum. © 2009 Wiley‐Liss, Inc.