bluuebunny/crossref_metadata_2025 huggingface dataset:
Cytologic examination of bronchoalveolar lavage fluid from immunosuppressed patients
Authors: Al‐Za'abi Ali Mohammed , MacDonald Scott , Geddie William , Boerner Scott L.
Published: October 2007

Pulmonary infiltrates in immunocompromised patients frequently represent infections. This study was undertaken to evaluate cytologic examination of bronchoalveolar lavage samples and the value of different preparations and silver staining. Over 6 mo, 336 samples were collected from 155 immunosuppressed patients in whom both cytologic and microbiologic studies were performed. In 27 samples, the cytology, microbiology or both demonstrated the presence of infectious agents. In four cases, cytology identified neoplastic process. Cytology had a sensitivity of 34.6% for detection of infection, which increased to 42.9% when Cytomegalovirus was excluded. Cytology detected 6 of 15 cases of Aspergillus, including three cases not detected by microbiology and 3 of 4 cases of Pneumocystis, but did not identify any of the Cytomegalovirus cases. The type of preparations did not affect detection of the organism when present in cytologic samples and silver staining did not appear to have added value in examination of these samples. Diagn. Cytopathol. 2007;35:710–714. © 2007 Wiley‐Liss, Inc.
Asymmetric Cyclization of 2′‐Hydroxychalcones to Flavanones: Catalysis by Chiral Brønsted Acids and Bases
Authors: Dittmer Claudia , Raabe Gerhard , Hintermann Lukas
Published: October 2007

The asymmetric cyclization of 2′‐hydroxychalcones to flavanones is a basic, enzyme‐catalyzed step in the biosynthesis of flavonoid natural products, but poses a long‐standing problem for asymmetric catalysis with small molecule catalysts. Earlier claims concerning the realization of an asymmetric flavanone synthesis by means of camphorsulfonic acid as chiral Brønsted acid catalysts were reinvestigated using accurate HPLC methods for quantification of enantiomer ratios. The previous claims of asymmetric induction were thus shown to be untenable. On the other hand, cinchona alkaloids serve as chiral Brønsted base mediators for the asymmetric cyclization of either 6′‐substituted 2′‐hydroxychalcones or 2′,6′‐dihydroxychalcones. 2′,6′‐Dihydroxy‐4,4′‐dimethoxychalcone, for instance, cyclized to give the naturally occurring naringenin‐4′,7‐dimethyl ether in up to 64 % ee at 81 % conversion. The catalysis shows a marked dependency of the enantiomeric excess of the product on the catalyst, solvent and reactant concentration. Based on these successful examples of asymmetric cyclizations of 2′‐hydroxychalcones to flavanones, requirements for more active asymmetric catalysts can be defined.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Fullerene Derivatives Substituted with Differently Branched Phenyleneethynylene Dendrons: Synthesis, Electronic and Excited State Properties
Authors: Clifford John N. , Gégout Aline , Zhang Sheng , Pereira de Freitas Rossimiriam , Urbani Maxence , Holler Michel , Ceroni Paola , Nierengarten Jean‐François , Armaroli Nicola
Published: October 2007

Fullerene derivatives functionalized with isomeric phenyleneethynylene‐based dendrons possessing either 1,3,5‐triethynylbenzene or 1,2,4‐triethynylbenzene branching units have been prepared. The electrochemical properties of these compounds are not strongly dependent on the branching patterns since the corresponding redox processes are localized either on the C60 cage (acceptor unit) or on the dialkyloxybenzene moieties (donor units) at the dendron periphery. The photophysical investigations performed in CH2Cl2 have revealed an ultrafast dendron → C60 energy transfer in all these hybrid systems. Importantly, the different π‐conjugation patterns in the two series have a dramatic effect on their electronic properties as attested by the differences observed in their absorption and emission spectra. The lower lying absorption onset and the wider spectral profile of the dyads with 1,2,4‐triethynylbenzene branching units when compared to their 1,3,5‐triethynylbenzene analogues clearly points out an improved light harvesting capability. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Dealing with the past and facing the future: mediators of the effects of collective guilt and shame in Bosnia and Herzegovina
Authors: Brown Rupert , Cehajic Sabina
Published: October 2007

Two studies are reported which examined potential mediators of the effects of collective guilt and shame on reparation attitudes. Samples of young Bosnian Serbs (Ns = 173, 247) were asked to report their feelings of guilt and shame for what their group had done during the 1992–1995 war in Bosnia Herzegovina. They also reported their attitudes towards making reparation to Bosnian Muslims. Both collective guilt and shame positively predicted reparation attitudes, but these associations were differently mediated. The effects of guilt were mediated by empathy for the outgroup, while the effects of shame were mediated by self‐pity and empathy. The theoretical and applied implications of these findings are discussed. Copyright © 2007 John Wiley & Sons, Ltd.
Simultaneous chiral resolution of monosaccharides as 8‐aminonaphthalene‐1,3,6‐trisulfonate derivatives by ligand‐exchange CE using borate as a central ion of the chiral selector
Authors: Kodama Shuji , Aizawa Sen‐ichi , Taga Atsushi , Yamashita Tomohisa , Kemmei Tomoko , Yamamoto Atsushi , Hayakawa Kazuichi
Published: October 2007

Six reducing monosaccharides (mannose, galactose, fucose, glucose, xylose, and arabinose) were derivatized with 8‐aminonaphthalene‐1,3,6‐trisulfonate (ANTS). Based on the chiral ligand‐exchange principle using borate as a central ion of the chiral selector and (S)‐3‐amino‐1,2‐propanediol (SAP) as a chiral selector ligand, all of the six ANTS‐monosaccharides were simultaneously enantioseparated using absorbance at 245 nm for detection. The optimum conditions for both high resolution and moderately short migration time consisted of 200 mM SAP–200 mM borate buffer (pH 9.2) containing 10% ACN as a BGE at 30°C with an applied voltage of +30 kV. It was revealed that the proposed chiral ligand‐exchange CE using the SAP–borate system was applicable to enantioseparation of not only diols but also polyols.
Optimization of structural control via a smart NEURO‐FBG control system
Authors: Lin Tzu‐Kang , Chiu Jen‐Chang , Chang Kuo‐Chun
Published: October 2007

This study improves a NEURO‐FBG active control system to mature the concept of a smart structure. Originally, a system similar to the human brain is created from FBG sensors and neural networks. The system comprises three parts, namely, a structural condition surveillance system, a NEURO‐FBG converter, and a NEURO‐FBG controller. To solve the inherent time‐consuming and reliability problem of the NEURO‐FBG converter, a new technology is first proposed, and the relationship between inter‐story drift and strain data is established. Global indices such as displacement and velocity of the structure are then reconstructed for searching the optimal control force of the actuator. Meanwhile, the soundness of a building with hydraulic actuators is also an important issue to be solved. To make the building sound, the characteristics of earthquakes are considered for enhancing the performance of the NEURO‐FBG controller. Theoretical analysis shows satisfactory improvement to the control efficiency of both displacement and acceleration. To verify the enhanced system, a series of shaking table tests was conducted. Experimental results demonstrated that the new NEURO‐FBG system can effectively manage the structure; and the controller, taking into consideration the ground acceleration effect, is more reliable and robust for practical application than a conventional controller. Copyright © 2007 John Wiley & Sons, Ltd.
Palynological studies on Egyptian species of subfamily Asteroideae‐Compositae (tribes Astereae, Calenduleae and Eupatorieae)
Authors: El‐Garf I. I. A. , Osman A. K.
Published: October 2007

Pollen morphology of twelve species representing ten genera of subfamily Asteroideae‐Compositae (tribes Astereae, Calenduleae and Eupatorieae) was investigated using light and scanning electron microscopy. Pollen were studied to show all possible characteristic features like shape, size, apertures, wall stratification … etc., with special reference to the specific characters of each pollen type. Three pollen types were recognized viz Calenduleae pollen type, Grangeinae pollen type, and Conyza pollen type. Description of each type, a key to the investigated taxa as well as light and scanning electron microscope. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Taxonomical significance of the morphological and scanning electron microscopic surface patterns of cypselas in some members of the tribe Heliantheae (Asteraceae)
Authors: Garg S. K. , Sharma K. C.
Published: October 2007

Data on morphological, histological and scanning electron microscopic studies on cypselas in 23 species belonging to nine subtribes of the tribe Heliantheae (Asteraceae) are presented. Developmental anatomy in two representative species showed that the two zoned ovary wall matures into a pericarp where the two zones are cemented by a black coloured deposition. The middle layers degenerate at maturity and only two layered seed coat persists. The surface patterns as revealed by SEM are species specific with some common similarities. Based on these characters supplemented by the histo‐morphological characters of the cypselas, a tentative key for identification and interrelationships of the species studied have been prepared. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bibliographia phytosociologica Mongolia
Authors: Hilbig W.
Published: October 2007

In Ergänzung zu den bisherigen zwei Teilen der Bibliographie vegetationskundlicher, vegetationsökologischer, floristischer und pflanzengeographischer Arbeiten über die Mongolei wird in vorliegender Arbeit Teil III der Bibliographie vorgelegt. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural and metamorphic evolution of the phengite‐bearing schists of the northern Adula Nappe (Central Alps, Switzerland)
Authors: Zulbati F.
Published: October 2007

Phengite‐bearing schists of the northern Adula Nappe experienced a polymetamorphic and polycyclic evolution that was associated with five deformation episodes. Evidence of a pre‐Alpine metamorphic event is preserved within garnet cores of some amphibole‐bearing schists. The D1 and D2 deformation episodes are recorded by S1 and S2 foliations preserved only within metre‐scale domains of low‐D3 strain. S1 is a relict foliation. Blueschist‐facies conditions at 565 ± 10°C and 11.5 ± 1.5 kbar were attained during D2 and were associated with the development of isoclinal folding and an S2 foliation. The D3 episode took place at 665 ± 50°C and 11.5 ± 2.1 kbar and was responsible for the development of a transpositive S3 foliation. The D4 episode took place at T < 550 ± 10°C and was associated with the development of a discrete S4 foliation and S‐C structures. The D5 episode is recorded by sub‐vertical metre‐scale open folds or centimetre‐scale kinks.

The structural and metamorphic evolution described here indicates that the northern and central parts of the Adula Nappe were distinct continental crustal fragments and were brought together under amphibolite‐facies conditions. Copyright © 2007 John Wiley & Sons, Ltd.
Effects of indoor gardening on sleep, agitation, and cognition in dementia patients—a pilot study
Authors: Lee Y. , Kim S.
Published: October 2007

Objective

A pilot study was performed to examine the efficacy of indoor gardening on sleep, agitation and cognition of dementia patients.

Method

Twenty‐three institutionalized dementia patients who had sleep disturbance and/or agitation participated in a 5‐week study protocol of 1 week of baseline and 4 weeks of treatment. The study design was a one group repeated measures study. For the first and fifth week of the study period, sleep patterns, agitation, and cognition were evaluated using a sleep diary, Modified Cohen‐Mansfield Agitation Inventory and revised Hasegawa Dementia Scale respectively.

Results

Significant improvement in wake after sleep onset, nap, nocturnal sleep time, and nocturnal sleep efficiency was identified. On the contrary sleep onset time, wake‐up time, total sleep time did not change after indoor gardening. Agitation and cognition score was significantly improved.

Conclusion

Indoor gardening was found to be effective for sleep, agitation, and cognition of dementia patients. Randomized controlled studies of larger sample size are needed to confirm treatment effect. Copyright © 2007 John Wiley & Sons, Ltd.
Hippocampal involvement in recollection but not familiarity across time: A prospective study
Authors: Suchan Boris , Gayk Anna E , Schmid Gebhard , Köster Odo , Daum Irene
Published: October 2007

For medial temporal lobe (MTL) involvement in memory formation, it is as yet unclear whether the MTL represents a single or dual (recollection/familiarity) memory system. A further controversial issue is whether or not the hippocampus is critical for the familiarity component of recognition memory. The present prospective fMRI study aimed to investigate changes of MTL involvement in recollection and familiarity at three time points following new learning: immediately after encoding, after 3 weeks and after 6 weeks. Significant hippocampal activation was observed for recollection relative to correct rejection responses at all three intervals. In addition, a decrease of signal changes in the perirhinal cortex was observed for the familiarity versus correct rejection contrasts. These findings support the idea that the MTL is a dual memory system. They also indicate a lasting hippocampal involvement in the recollection component of recognition memory and a decrease of perirhinal cortex activation associated with familiarity for time periods up to 6 weeks after new learning. © 2007 Wiley‐Liss, Inc.
Continuous drip infusion of low dose cytarabine and etoposide with granulocyte colony‐stimulating factor for elderly patients with acute myeloid leukaemia ineligible for intensive chemotherapy
Authors: Kanemura Nobuhiro , Tsurumi Hisashi , Kasahara Senji , Hara Takeshi , Yamada Toshiki , Sawada Michio , Goto Naoe , Kitagawa Jun‐ichi , Shimizu Masahito , Oyama Masami , Moriwaki Hisataka
Published: October 2007

Backgrounds and objectives

The optimal strategy for the management of elderly patients with acute myeloid leukaemia (AML) is still controversial. We previously reported the effectiveness of low dose cytarabine (Ara‐C) and etoposide (VP‐16) (AV therapy) for those elderly AML patients ineligible for intensive chemotherapy. We initiated the present feasibility study to improve the efficacy by using glanulocyte‐colony stimulating factor (G‐CSF) with AV therapy (AVG therapy).

Patients and methods

The eligibility for enrolment was AML patients according to the World Health Organization (WHO) criteria who were over 60 years of age and who had difficulty in tolerating intensive chemotherapy due to their poor performance status (PS) or some comorbidities. They were given continuous drip infusion of Ara‐C (20 mg/body) and VP‐16 (50 mg/body) for 7–14 days, and were also simultaneously administered G‐CSF (150 μg/m2) once daily.

Results

The median age of consecutively enrolled 25 patients was 73 years. Eighteen (72%) patients achieved complete remission (CR). The 1‐year overall survival (OS) and the 3‐year OS rates were 69% and 22%, respectively. The 1‐year disease free survival (DFS) rate in CR patients was 44%. The major regimen related toxicities of grade 3 or 4 were only febrile neutropenia in 15 patients (60%). No regimen‐related mortality was observed.

Conclusion

AVG therapy was therefore found to be an effective and well‐tolerated regimen for remission induction in elderly AML patients with poor PS or comorbidity. Copyright © 2007 John Wiley & Sons, Ltd.
Tide‐induced groundwater head fluctuation in a coastal aquifer system with a submarine outcrop covered by a thin silt layer
Authors: Ren Yakun , Tang Zhonghua , Zhao Lichun
Published: October 2007

We present an analytical solution of groundwater head response to tidal fluctuation in a coastal multilayered aquifer system consisting of an unconfined aquifer, a leaky confined aquifer and a semi‐permeable layer between them. The submarine outcrop of the confined aquifer is covered by a thin silt layer. A mathematical model and the analytical solution of this model are given. The silt layer reduces the amplitude of the hydraulic head fluctuation by a constant factor, and shifts the phase by a positive constant (time lag), both of which depend on the leakances of the silt layer and the semi‐permeable layer. The time lag is less than 1·5 h and 3·0 h for semi‐diurnal and diurnal sea tides respectively. When the leakance of the semi‐permeable layer or the silt layer assumes certain special values, the solution becomes the existing solutions derived by previous researchers. The amplitude of the hydraulic head fluctuation in the confined aquifer increases with the leakance of the silt layer and decreases with the leakance of the semi‐permeable layer, whereas the phase shift of the fluctuation decreases with both of them. A hypothetical example shows that neglecting the silt layer may result in significant parameter estimation discrepancy between the amplitude attenuation and the time‐lag fittings. Copyright © 2007 John Wiley & Sons, Ltd.
Bacteria transport in an unsaturated porous media: incorporation of air–water interface area model into transport modelling
Authors: Kim Min‐Kyu , Kim Song‐Bae , Park Seong‐Jik
Published: October 2007

The bacterial transport model into which the air–water interface (AWI) area model is incorporated is developed in this study. At the outset, the AWI area models are analysed to determine the appropriate model. In the analysis, three models are evaluated with the previously reported experimental data, and the modified form of the Niemet et al. (2002) model is selected as an appropriate AWI area model, which is then combined into the transport model. The bacterial transport model is used to fit the bacterial breakthrough data in an unsaturated porous media from the literature, and the fitting results show that the model matches well with the observed data at three different air contents by varying the specific AWI area. On the basis of the sorption‐related parameters determined from the literature, simulations are performed to examine bacterial transport in three different soils under unsaturated and transient flow conditions. The results illustrate that bacteria can travel to different depths in unsaturated soils depending on the soil type and water content. Even if the predictive model presented in this study is not comprehensive, it will help to understand bacterial transport behaviour in an unsaturated porous media. Copyright © 2007 John Wiley & Sons, Ltd.
Spectrophotometric properties of surface water dissolved organic matter in an afforested upland peat catchment
Authors: Baker Andy , Bolton Lucy , Newson Malcolm , Spencer Robert G. M.
Published: October 2007

Many upland catchments in the UK have undergone afforestation; their characteristic waterlogged soils require extensive pre‐plantation ground drainage to allow tree establishment. In peatland areas this can result in very highly coloured runoff and enhanced dissolved organic matter (DOM) export in rivers of naturally high concentrations. In 1966, the Coalburn Experimental Catchment, northern England, was established to investigate the impact of afforestation on an upland peat catchment. Here we report the variations in DOM spectrophotometric properties of streamflow in the catchment at canopy closure, especially with respect to potential carbon sources within the artificial drainage ditches. Drainage ditches are characterized by water that has higher absorption coefficients and which is more highly coloured than in the catchment tributaries. Ditched, afforested areas produce more highly‐coloured runoff waters that are more fluorescent and absorbent normalized to carbon concentration compared to ditches in open moorland. Ditches that had been experimentally re‐excavated have organic matter of different spectrophotometric character, with higher dissolved organic carbon concentration and less aromatic or lower molecular weight material. It is hypothesized that this is due to the exposure of bare peat faces within and adjacent to the ditches that are more susceptible to drying compared to vegetated areas. The large extent of this drainage network acts as both a rapid transport network increasing hydrological connectivity and a pool for the storage of DOM, which is of different spectrophotometric character under low flow conditions, depending on management conditions. Copyright © 2007 John Wiley & Sons, Ltd.
Response of plant growth to surface water balance during a summer dry period in the Kazakhstan steppe
Authors: Iijima Yoshihiro , Kawaragi Tsuneo , Ito Takehiko , Akshalov Kanat , Tsunekawa Atsushi , Shinoda Masato
Published: October 2007

In drylands, water deficit is the primary factor limiting plant growth. In the present study, surface energy balance and plant growth (above‐ground and below‐ground biomass) were measured continuously during the 2002 growing season in semiarid grassland in the northern part of Kazakhstan, Central Asia. Although there was above normal total rainfall during the 2002 growing season (May–November; 244 mm over 183 days), there was a dry period during July and August. Evaporative water was effectively supplied by precipitation and surface soil moisture during the wet season (May and June), during which time above‐ground biomass increased. During the early stages of the dry period, mature plants were likely to tap deeper sources of soil moisture, representing stored snowmelt water. As the soil moisture content decreased during the summer dry period due to the high levels of evapotranspiration and lack of precipitation, the evaporative fraction and above‐ground biomass rapidly decreased, whereas the below‐ground biomass increased. These results suggest that in summer, soil moisture acts to store water, and that soil moisture is essential for plant growth as a direct source of water during the dry period in natural grasslands in the Kazakhstan steppe. Copyright © 2007 John Wiley & Sons, Ltd.
Modelling the probability of occurrence of shallow landslides and channelized debris flows using GEOtop‐FS
Authors: Simoni Silvia , Zanotti Fabrizio , Bertoldi Giacomo , Rigon Riccardo
Published: October 2007

This paper describes a coupled, distributed, hydrological‐geotechnical model, GEOtop‐FS, which simulates the probability of occurrence of shallow landslides and debris flows. We use a hydrological distributed model, GEOtop, which, models latent and sensible heat fluxes and surface runoff, and computes soil moisture in 3‐D by solving Richards'equation numerically, together with an infinite‐slope geotechnical model, GEOtop‐FS. The combined model allows both the hydraulic and geotechnical properties of soil to be considered and realistically modelled. In particular, the model has been conceived to make direct use of field surveys, geotechnical characteristics and soil moisture measurements. In the model the depth of available sediments is also used to characterize the hydraulic properties of the area examined.

To account for the uncertainty related to the natural variability in the factors influencing the stability of natural slopes, the safety factor is computed with a probabilistic approach. In order to determine the likelihood of slope failures, soil parameters are assigned distributions instead of single deterministic values.

The analysis presented was carried out for an alpine watershed, located in the Friuli region, Italy, for which some geological and geotechnical data were available. In the past, this watershed experienced landslides and debris flows during intense storms following long and moderate intensity rainfall events. The distributed coupled GEOtop‐FS model was calibrated by reproducing some of these events and validated in order to map future failure probabilities. Copyright © 2007 John Wiley & Sons, Ltd.
Vulnerability of water resources, vegetation productivity and soil erosion to climate change in Mediterranean watersheds
Authors: Nunes João Pedro , Seixas Júlia , Pacheco Nuno Ricardo
Published: October 2007

Climate change is expected to increase temperatures and lower rainfall in Mediterranean regions; however, there is a great degree of uncertainty as to the amount of change. This limits the prediction capacity of models to quantify impacts on water resources, vegetation productivity and erosion. This work circumvents this problem by analysing the sensitivity of these variables to varying degrees of temperature change (increased by up to 6·4 °C), rainfall (reduced by up to 40%) and atmospheric CO2 concentrations (increased by up to 100%). The SWAT watershed model was applied to 18 large watersheds in two contrasting regions of Portugal, one humid and one semi‐arid; incremental changes to climate variables were simulated using a stochastic weather generator. The main results indicate that water runoff, particularly subsurface runoff, is highly sensitive to these climate change trends (down by 80%). The biomass growth of most species showed a declining trend (wheat down by 40%), due to the negative impacts of increasing temperatures, dampened by higher CO2 concentrations. Mediterranean species, however, showed a positive response to milder degrees of climate change. Changes to erosion depended on the interactions between the decline in surface runoff (driving erosion rates downward) and biomass growth (driving erosion rates upward). For the milder rainfall changes, soil erosion showed a significant increasing trend in wheat fields (up to 150% in the humid watersheds), well above the recovery capacity of the soil. Overall, the results indicate a shift of the humid watersheds to acquire semi‐arid characteristics, such as more irregular river flows and increasingly marginal conditions for agricultural production. Copyright © 2007 John Wiley & Sons, Ltd.
Groundwater–surface water interactions, nutrient fluxes and ecological response in river corridors: Translating science into effective environmental management
Authors: Smith J. W. N. , Bonell M. , Gibert J. , McDowell W. H. , Sudicky E. A. , Turner J. V. , Harris R. C.
Published: October 2007

A summary is provided of the second in a series of Integrated Science Initiative workshops supported by the UNESCO International Hydrological Programme. The workshop brought together hydrologists, ecologists, biogeochemists, hydrogeologists and natural resource managers to discuss the processes that occur in hyporheic and riparian ecotones. The principal objectives were to share new ideas on the importance of biogeochemical processes that affect nutrients at the groundwater–surface water interface, to understand the impact of nutrient flux on stream (principally hyporheic) ecology, and to identify the management strategies for river corridors to mitigate the effects of nutrients applied to land and discharged via groundwater into rivers. The workshop concluded that: (1) more interdisciplinary research and environmental management practices are needed to better understand, predict and manage processes at the interface of environmental compartments; (2) the goal of environmental regulations to improve ecological health requires a holistic approach integrating our understanding of the ecological, hydrological, biogeochemical and physical processes; (3) upscaling spatially and temporally variable processes remains difficult and may hinder translation of research at micro‐scales (molecular to grain size) into macro‐scale (reach to catchment) decision‐making; (4) scientists need to better communicate existing research to river managers, while smanagers must better communicate policy and regulatory‐driven science requirements to researchers. Existing models, such as those that simulate stream–hyporheic exchange, are not widely known and rarely used by environmental managers. Copyright © 2007 John Wiley & Sons, Ltd.
Effects of carboxyamidotriazole on in vitro models of imatinib‐resistant chronic myeloid leukemia
Authors: Alessandro Riccardo , Fontana Simona , Giordano Margherita , Corrado Chiara , Colomba Paolo , Flugy Anna Maria , Santoro Alessandra , Kohn Elise C. , De Leo Giacomo
Published: October 2007

Although imatinib mesylate (IM) has revolutionized the treatment of chronic myeloid leukemia (CML), some patients develop resistance with progression of leukemia. Alternative or additional targeting of signaling pathways deregulated in bcr‐abl‐driven CML cells may provide a feasible option for improving clinical response and overcoming resistance. In this study, we show that carboxyamidotriazole (CAI), an orally bioavailable calcium influx and signal transduction inhibitor, is equally effective in inhibiting the proliferation and bcr‐abl dependent‐ and independent‐signaling pathways in imatinib‐resistant CML cells. CAI inhibits phosphorylation of cellular proteins including STAT5 and CrkL at concentrations that induce apoptosis in IM‐resistant CML cells. The combination of imatinib and CAI also down‐regulated bcr‐abl protein levels. Since CAI is already available for clinical use, these results suggest that it may be an effective addition to the armamentarium of drugs for the treatment of CML. J. Cell. Physiol. 215: 111–121, 2008. © 2007 Wiley‐Liss, Inc.
Engineering a circularly permuted GFP scaffold for peptide presentation
Authors: Paschke Matthias , Tiede Christian , Höhne Wolfgang
Published: October 2007

The use of peptides as in vivo and in vitro ligand binding agents is hampered by the high flexibility, low stability and lack of intrinsic detection signal of peptide aptamers. Recent attempts to overcome these limitations included the integration of the binding peptide into a stable protein scaffold. In this paper, we present the optimization and testing of a circularly permuted variant of the green fluorescent protein (GFP). We examined the ability of the optimized scaffold to accept peptide insertions at three different regions. The three regions chosen are localized in close spatial proximity to each other and support different conformations of the inserted peptides. In all the three regions peptides with a biased, but still comprehensive, amino acid repertoire could be presented without disturbing the function of the optimized GFP‐scaffold. Copyright © 2007 John Wiley & Sons, Ltd.
Properties and molecular evolution of human GLUD2 (neural and testicular tissue‐specific) glutamate dehydrogenase
Authors: Kanavouras Konstantinos , Mastorodemos Vasileios , Borompokas Nikolas , Spanaki Cleanthe , Plaitakis Andreas
Published: October 2007

Glutamate dehydrogenase (GDH) is an enzyme central to the metabolism of glutamate that also plays a role in cellular energetics. In the human, GDH exists in a housekeeping isoenzyme (hGDH1) encoded by the GLUD1 gene and a neural and testicular tissue‐specific isoform (hGDH2) encoded by the GLUD2 gene. There is evolutionary evidence that the GLUD1 was retroposed to the X chromosome in the ape ancestor (>23 million years ago), where it gave rise to GLUD2 through random mutations and directional selection. In the human, the two mature GDH isoproteins are highly homologous, differing in only 16 of their 505 amino acid residues. Functional analyses of highly purified recombinant wild‐type hGDH2 revealed that this adaptive evolution dissociated the enzyme from GTP control, permitted regulation almost entirely by ADP and/or L‐leucine, and fine‐tuned its activity to the relatively low cellular pH that occurs in synaptic astrocytes during excitatory transmission. Study of structure‐function relationships, using site‐directed mutagenesis of GLUD1 at single sites differing from GLUD2, showed that the Arg443Ser and the Gly456Ala change reproduced some, but not all, of the properties of hGDH2. In addition, we created a double hGDH1 mutant that had both Arg443Ser and Gly456Ala in the same polypeptide chain. Functional analyses revealed that the doubly mutated enzyme did not acquire all the characteristics of the wild‐type hGDH2. Hence, additional amino acid changes, acting in concert with Arg443Ser and Gly456Ala, ought to be responsible the unique properties of the brain‐specific human isoenzyme. © 2007 Wiley‐Liss, Inc.
Seasonality of modern pollen and sediment deposition in an estuarine context: the Severn Estuary Levels, southwest England
Authors: Allen J. R. L. , Dark Petra
Published: October 2007

Recent sedimentological and palynological research on subfossil Holocene banded sediments from the Severn Estuary Levels suggested seasonality of deposition, registered by variations in mineral grain‐size and pollen assemblages between different parts of the bands. Here we provide data that strengthen this interpretation from sampling of modern sediments and pollen deposition on an active mudflat and saltmarsh on the margin of the Severn Estuary, and comparison with a vegetation survey and contemporary records of climate, river and tidal regimes. The results of grain‐size analysis indicate deposition of comparatively coarse‐grained silts during the relatively cool and windy conditions of winter and comparatively fine‐grained sediments during relatively warm and calm summer months. Pollen analysis demonstrates the significance of long‐term storage of pollen grains and fern spores in the estuarine waterbody, superimposed on which seasonal variations in pollen inputs from local and regional vegetation remain detectable. Copyright © 2007 John Wiley & Sons, Ltd.
Electrochromatographic separation on a poly(dimethylsiloxane)/glass chip by integration of a capillary containing an acrylate monolithic stationary phase
Authors: Blas Maximilien , Delaunay Nathalie , Rocca Jean‐Louis
Published: October 2007

In this paper, we present an approach to perform electrochromatographic separations on poly(dimethylsiloxane) chips: a fused‐silica capillary containing a stationary phase was introduced directly into the chip. This approach would offer great flexibility since capillary modification methods are well known, and thus, with this kind of chip, different microfluidic devices having various functionalizations could be prepared. Electrophoretic separations were first achieved by integrating an empty capillary into the chip to evaluate the analytical performances of this system. They were compared to those obtained with a classical chip. Finally, an electrochromatographic separation involving a capillary containing a hexyl acrylate‐based monolith was performed. These preliminary results show this approach to be promising.
Elementary reaction step model of the N‐nitrosation of ammonia
Authors: Silva Gabriel Da , Dlugogorski Bogdan Z. , Kennedy Eric M.
Published: October 2007

This contribution develops a comprehensive kinetic model of the N‐nitrosation reaction mechanism, consisting almost entirely of elementary reaction steps and applies it to study the nitrosation of ammonia. The reaction mechanism features 26 species and 22 reactions, with 8 parallel reaction pathways for ammonia nitrosation and a side pathway for nitrous acid decomposition. We compiled forward and reverse rate constants for each of the reactions, either from the literature sources or by correlation with known rate and equilibrium constants. The concentration of each reaction species with respect to time can be obtained for any set of initial concentrations by invoking a simultaneous solution to the system of ordinary differential equations describing the reaction mechanism. The model successfully predicts previous experimental results for ammonia nitrosation, with and without the addition of the catalyst thiocyanate. The effect of pH on the rate and mechanism of ammonia nitrosation was studied with the model. For uncatalyzed nitrosation, the results indicate that between pH 6.0 and 1.5 the reaction proceeds predominantly via reaction with N2O3, whereas ON+ nitrosation becomes the preferred pathway below pH 1.5. ONSCN is the dominant nitrosating agent across the entire pH range studied when the nucleophile thiocyanate was added in appreciable quantities. However, with the weak nucleophile Cl−, nitrosation by N2O3 and ON+ governed the reaction kinetics at high and low pH, respectively. We demonstrate that nitrosating agent formation is rapid and does not limit the rate of ammonia nitrosation; however, nitrosating agent formation could become the rate‐limiting step for the nitrosation of highly reactive substrates. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 39: 645–656, 2007
Metallomicelle catalysis: Hydrolysis of p‐nitrophenyl picolinate induced by Schiff base Co(II) complexes in a Gemini surfactant micellar solution
Authors: Jiang Weidong , Xu Bin , Li Jianzhang , Lin Qi , Zeng Xiancheng , Chen Hua
Published: October 2007

Two Schiff base cobalt(II) complexes containing crowned substituents have been synthesized and employed to promote the hydrolysis of p‐nitrophenyl picolinate (PNPP) in a buffered micellar solution formed by a cationic Gemini surfactant, bis(hexadecyldimethylammonium)hexane bromide (G(hex)C16, 2Br−) over a pH range of 6.50–8.50. In comparison, the reactivity of PNPP hydrolysis catalyzed by the same catalysts in the other micellar system, formed by a conventional single‐chain analogue, that is, hexadecyltrimethylammonium bromide (CTAB), has also been evaluated under a selected condition. The results clearly reveal that the two metallomicelles made of the aforementioned Co(II) complexes and the G(hex)C16 are both efficient for catalyzing PNPP hydrolysis with about 3 orders of magnitude in rate acceleration compared with the background rate of PNPP spontaneous hydrolysis. Moreover, the rates of PNPP hydrolysis catalyzed by the two cobalt(II) complexes in G(hex)C16 micelles are about 2 times higher than in CTAB micelles, correspondingly. In addition, observations show that steric hindrance of substituents of the two complexes is also one of the major influencing factors in the PNPP hydrolytic reaction. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 39: 672–680, 2007
A Novel Poly(4‐methyl‐2‐pentyne)/TiO2 Hybrid Nanocomposite Membrane for Natural Gas Conditioning: Butane/Methane Separation
Authors: Yave Wilfredo , Shishatskiy Sergey , Abetz Volker , Matson Samira , Litvinova Elena , Khotimskiy Valeriy , Peinemann Klaus‐Viktor
Published: October 2007

Poly(4‐methyl‐2‐pentyne) (PMP)/TiO2 hybrid nanocomposite membranes have been investigated for natural gas conditioning. Tailor‐made PMP with 35% cis‐content was identified as an attractive material to prepare nanocomposite membranes; it presented good stability towards organic vapors and optimal properties for butane/methane separation. The PMP/TiO2 hybrid nanocomposite membranes presented an improvement of butane permeability and butane/methane selectivity. The addition of TiO2 nanoparticles to the PMP enhanced the selectivity more effectively than fumed‐silica, and it is attractively higher than those currently reported in the open literature.

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Fabrication of Superhydrophobic and Superoleophilic Polystyrene Surfaces by a Facile One‐Step Method
Authors: Tu Cheng‐Wei , Tsai Chia‐Hua , Wang Chih‐Feng , Kuo Shiao‐Wei , Chang Feng‐Chih
Published: October 2007

A facile one‐step method has been developed to prepare both superhydrophobic and superoleophilic surfaces of polystyrene (PS) without any chemical modification. A rough film consisting of micro‐bead and nano‐fiber mixed structures is formed by spraying a PS solution onto a large area and any type of substrate. The mixed structures with such unique wettability properties can be used in oil/water separation and as oil sorbents.

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A Click Approach to Chiral‐Dendronized Polyfluorene Derivatives
Authors: Liu Zi‐Tong , He Yan‐Mei , Li Bao‐Lin , Liu Ji , Fan Qing‐Hua
Published: October 2007

A new kind of chiral‐dendronized binaphthyl‐containing polyfluorene derivatives has been synthesized through “click chemistry” efficiently. The resulting copolymers exhibited desirable properties, such as excellent solubility, good thermal stability, and considerably high molecular weights. The photophysical properties of the copolymers were investigated in details, and the results indicated that the combination of chiral binaphthyl unit and bulky dendron could effectively suppress intermolecular packing and aggregation. In addition, the investigation of circular dichroism behavior of these chiral‐dendronized copolymers showed a strong Cotton effect at long wavelength (373–379 nm), indicating that the chirality of the binaphthyl units was transferred to the whole polyfluorene backbone.

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Novel Anti‐Microbial Host‐Guest Complexes Based on Cationic β‐Cyclodextrin Polymers and Triclosan/Butylparaben
Authors: Guan Yong , Qian Liying , Xiao Huining
Published: October 2007

The preparation of novel cationic β‐cyclodextrin polymers (CPβCDs) and its complexes with butylparaben and triclosan were reported in this paper. FT‐IR and two‐dimensional (2D) 1H–1H gradient correlated spectroscopy (gCOSY) NMR spectra confirmed that the antibiotics could be included inside the lipophilic cavities of CPβCDs. The water solubility of the antibiotics was improved significantly after inclusion with CPβCDs. The results also suggest that it was easier for butylparaben, which had relatively small molecular size, to form the complexes with CPβCDs than triclosan. Due to the targeting effect after the inclusion with cationic CPβCDs, the anti‐microbial activity of butylparaben was also enhanced substantially. However, similar improvement was not obvious for triclosan.

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Isolation and identification of metabolites from dihydromyricetin
Authors: Zhang Yansong , Que Sheng , Yang Xiuwei , Wang Bin , Qiao Liang , Zhao Yuying
Published: October 2007

Dihydromyricetin (DHM) is the major bioactive constituent of Rattan Tea, which is the tender stems and leaves of Ampelopsis grossendentata. Seven metabolites (2–8) of DHM (1) were obtained by the chromatographic method. The metabolites 2–5 were obtained from the urine of rats administered orally with DHM; and metabolites 6–8 were detected in the fecal specimens of rats, which were also produced by human intestinal bacteria (HIB) in vitro, and were separated from the cultured media of HIB containing DHM. Their structures were elucidated as 5,7,3′,5′‐tetrahydroxyflavanonol (2); 5,7,3′,5′‐tetrahydroxy‐4′‐methoxyflavanonol (3); 5,7,4′,5′‐tetrahydroxy‐3′‐methoxyflavanonol (4); and dihydromyricetin‐O‐5‐β‐D‐glucuronide (5); (2R,3S)‐5,7,3′,4′,5′‐pentahydroxyflavanonol (6); 3,4,5,7,3′,4′,5′‐hepthydroxyflavan (7) and 5,7,3′,4′,5′‐pentahydroxyflavanone (8) on the basis of UV, NMR and LC‐MS/MS data. These seven metabolites were formed through familiar metabolic reactions. Dihydromyricetin‐O‐5‐β‐D‐glucuronide (5) is a new compound. The 13C‐NMR data of (2) and (4) are reported for the first time. Copyright © 2007 John Wiley & Sons, Ltd.
Purity analysis of hydrogen cyanide, cyanogen chloride and phosgene by quantitative 13C NMR spectroscopy
Authors: Henderson Terry J. , Cullinan David B.
Published: October 2007

Hydrogen cyanide, cyanogen chloride and phosgene are produced in tremendously large quantities today by the chemical industry. The compounds are also particularly attractive to foreign states and terrorists seeking an inexpensive mass‐destruction capability. Along with contemporary warfare agents, therefore, the US Army evaluates protective equipment used by warfighters and domestic emergency responders against the compounds, and requires their certification at ≥ 95 carbon atom % before use. We have investigated the 13C spin‐lattice relaxation behavior of the compounds to develop a quantitative NMR method for characterizing chemical lots supplied to the Army. Behavior was assessed at 75 and 126 MHz for temperatures between 5 and 15 °C to hold the compounds in their liquid states, dramatically improving detection sensitivity. T1 values for cyanogen chloride and phosgene were somewhat comparable, ranging between 20 and 31 s. Hydrogen cyanide values were significantly shorter at 10–18 s, most likely because of a 1H13C dipolar contribution to relaxation not possible for the other compounds. The T1 measurements were used to derive relaxation delays for collecting the quantitative 13C data sets. At 126 MHz, only a single data acquisition with a cryogenic probehead gave a signal‐to‐noise ratio exceeding that necessary for certifying the compounds at ≥ 95 carbon atom % and 99% confidence. Data acquired at 75 MHz with a conventional probehead, however, required ≥ 5 acquisitions to reach this certifying signal‐to‐noise ratio for phosgene, and ≥ 12 acquisitions were required for the other compounds under these same conditions. In terms of accuracy and execution time, the NMR method rivals typical chromatographic methods. Published in 2007 by John Wiley & Sons, Ltd.
The 14N quadrupole coupling in hexamethylene triperoxide diamine (HMTD)
Authors: Persons John , Harbison Gerard S.
Published: October 2007

Using high‐field NMR, we have determined the magnitude of the nuclear quadrupole interaction in hexamethylene triperoxide diamine (HMTD), the explosive allegedly used in the London bombings of July 2005. The experimental quadrupolar coupling constant, 5.334 MHz, is in good agreement with quantum chemical calculations. The predicted single zero‐field transition frequency should lie in a relatively empty part of the 14N nuclear quadrupole resonance (NQR) spectrum; the spin relaxation rate is reasonably fast. Copyright © 2007 John Wiley & Sons, Ltd.
Solid state NMR characterization of individual compounds and solid solutions formed in Sc2O3V2O5Nb2O5Ta2O5 system
Authors: Khabibulin Dzhalil , Romanenko Konstantin , Zuev Mikhail , Lapina Olga
Published: October 2007

In this study, 51V, 45Sc and 93Nb MAS NMR combined with satellite transition spectroscopy analysis were used to characterize the complex solid mixtures: VNb9(1−x)Ta9xO25, ScNb(1−x)TaxO4 and ScNb2(1−x)Ta2xVO9 (x = 0, 0.3, 0.5, 0.7, 1.0). This led us to describe the structures of Sc and V sites. The conclusions were based on accurate values for 51V quadrupole coupling and chemical shift tensors obtained with 51V MAS NMR/SATRAS for VNb9O25, VTa9O25 and ScVO4. The 45Sc NMR parameters have been obtained for Sc2O3, ScVO4, ScNbO4 and ScTaO4. On the basis of 45Sc NMR and data available from literature, the ranges of the 45Sc chemical shift have been established for ScO6 and ScO8. The gradual change of the 45Sc and 51V NMR parameters with x confirms the formation of solid solutions in the process of synthesis of VNb9(1−x)Ta9xO25 and ScNb(1−x)TaxO4, in contrast to ScNb2(1−x)Ta2xVO9. The cation sublattice of ScNb(1−x)TaxO4 is found to be in octahedral coordination. The V sites in VNb9(1−x)Ta9xO25 are present in the form of slightly distorted tetrahedra. The 93Nb NMR parameters have been obtained for VNb9O25. Copyright © 2007 John Wiley & Sons, Ltd.
Direct observation of the unstable intermediates in radical addition reaction by using an interfacing microchip combined with an NMR
Authors: Nakakoshi Masamichi , Ueda Masafumi , Sakurai Satoshi , Asakura K. , Utsumi Hiroshi , Miyata Okiko , Naito Takeaki , Takahashi Yutaka
Published: October 2007

Direct observation of the unstable intermediate in the radical addition reaction of the oxime ether 1 mediated by triethylborane (Et3B) is described using 1H and 11B micro channeled cell for synthesis monitoring (MICCS), which was recently developed as an interfacing microchip for NMR. It was possible that the signal of the intermediate was observed as a result of using MICCS technique with a standard NMR instrument. This result supports the structure of the intermediate analyzed by diffusion‐ordered spectroscopy (DOSY) NMR method in a previous paper. The procedure of micro channeled cell for synthesis monitoring‐nuclear magnetic resonance (MICCS‐NMR) was much easier than that of DOSY method. It was proven that it could be applied to the reaction in an anhydrous condition. Copyright © 2007 John Wiley & Sons, Ltd.