bluuebunny/crossref_metadata_2025 huggingface dataset:
Peripherally induced human regulatory T cells uncouple Kv1.3 activation from TCR‐associated signaling
Authors: Reneer Mary C. , Estes Daniel J. , Vélez‐Ortega Alejandra C. , Norris Andrea , Mayer Michael , Marti Francesc
Published: August 2011

Peripherally induced Tregs (iTregs) are being recognized as a functional and physiologically relevant T‐cell subset. Understanding the molecular basis of their development is a necessary step before the therapeutic potential of iTreg manipulation can be exploited. In this study, we report that the differentiation of primary human T cells to suppressor iTregs involves the relocation of key proximal TCR signaling elements to the highly active IL‐2‐Receptor (IL‐2‐R) pathway. In addition to the recruitment of lymphocyte‐specific protein tyrosine kinase (Lck) to the IL‐2‐R complex, we identified the dissociation of the voltage‐gated K+ channel Kv1.3 from the TCR pathway and its functional coupling to the IL‐2‐R. The regulatory switch of Kv1.3 activity in iTregs may constitute an important contributing factor in the signaling rewiring associated with the development of peripheral human iTregs and sheds new light upon the reciprocal crosstalk between the TCR and the IL‐2‐R pathways.
Simple and Efficient: Ethylene Glycol Isonitrile Gold(I) Chlorides for the Formation and Stabilization of Gold Nanoparticles
Authors: Tuchscherer André , Schaarschmidt Dieter , Schulze Steffen , Hietschold Michael , Lang Heinrich
Published: August 2011

Ethylene glycol isonitriles C≡N(CH2CH2O)nCH3 (5a, n = 1; 5b, n = 3; 5c, n = 4) with different chain lengths were prepared by using straightforward synthesis methodologies including the Gabriel synthesis and an Appel‐type reaction protocol. Upon treatment with [AuCl(SMe)2], compounds 5a–c gave the corresponding isocyanide gold(I) chlorides [AuCl{C≡N(CH2CH2O)nCH3}] (7a, n = 1; 7b, n = 3; 7c, n = 4). Single‐crystal X‐ray diffraction studies reveal a polymeric (7a) or dimeric (7c) structure with aurophilic interactions. Gold(I) complexes 7a–c were applied in the formation and stabilization of gold nanoparticles (AuNPs). The isonitriles with their ethylene glycol functionalities, which provide multiple donating capabilities, are able to stabilize the encapsulated gold colloids. The reduction of 7a–c by the addition of Na[BH4] in tetrahydrofuran or methanol produces AuNPs without the further addition of any stabilizer, since metal‐organic 7a–c combine the stabilizing component and gold source in one molecule. The dependency of different solvents, concentrations, and varying ethylene glycol chain lengths on the NP size and size distribution is reported. Characterization by TEM, UV/Vis spectroscopy, and XRPD revealed that AuNPs are formed with a size between 6.4(±1.4) to 9.5(±2.3) nm in methanol and 18.2(±2.3) to 27.2(±3.5) nm in tetrahydrofuran.
Carbon‐to‐Carbon Anion Relay Chemistry: Facile Generation of Substituted Allyllithium Species
Authors: Zheng Pinguan , Cai Zhengxin , Garimallaprabhakaran Aswinkumar , Rooshenas Parham , Schreiner Peter R. , Harmata Michael
Published: August 2011

Treatment of [2‐(2‐bromophenyl)allyl]trimethylsilane with tBuLi in THF at –78 °C resulted in the rapid migration of the trimethylsilyl group to afford an allylic organolithium that can be easily trapped by a wide range of electrophiles. This is a rare example of a synthetically useful and efficientcarbon‐to‐carbon migration of a silicon group and represents a new approach to allylic organolithium species using anion relay chemistry.
Preparation and Properties of Reference Electrodes Based on Silver Paste Amalgam
Authors: Yosypchuk Bogdan , Barek Jiří , Yosypchuk Oksana
Published: August 2011

The preparation and testing of saturated calomel electrodes (SCE‐AgPA), mercury‐mercurous sulfate (MMSE‐AgPA) and mercury‐mercuric oxide (MMOE‐AgPA) reference electrodes based on silver paste amalgam are described. All three electrodes have shown long‐term stability of their potentials (ESCE‐AgPA=−0.56±0.34 mV; EMMSE‐AgPA=391.5±1.4 mV; EMMOE‐AgPA=−104.9±0.7 mV vs. classical SCE; test time was 14 months). All paste amalgam electrodes have potentials close to their analogues with metallic mercury. They can therefore replace each other without any recalculation. Peak potentials of anodic dissolution of cadmium measured with the SCE‐AgPA and SCE are identical. The greatest resistance to polarization was registered with the SCE‐AgPA and significantly lower with other tested electrodes.
Sensitive Electrochemical Sensor for Determination of Methyldopa Based on Polypyrrole/Carbon Nanoparticle Composite Thin Film Made by In Situ Electropolymerization
Authors: Shahrokhian Saeed , Saberi Reyhaneh‐Sadat , Kamalzadeh Zahra
Published: August 2011

A composite surface coating is prepared by electropolymerization of a mixture of pyrrole and carbon nanoparticles onto a glassy carbon electrode (GCE). The microscopic structure and morphology of the composite film is characterized by scanning electron microscopy. The modified electrode offers a considerable improvement in voltammetric sensitivity toward methyldopa (m‐dopa), compared to the bare and polypyrrole‐coated GCEs. A significantly enhanced anodic peak current together with a remarkable increase in sharpness of the cyclic voltammetric (CV) signals are observed for the detection of m‐dopa. The effect of experimental parameters, such as scan rate and pH, are investigated by monitoring CV responses toward m‐dopa. It is found that a maximum current response can be obtained at pH 3.0 under a diffusion controlled process. A wide linear dynamic range (0.2–50 µM) with a detection limit of 60 nM is achieved for m‐dopa. The excellent response characteristics, e.g., high sensitivity, very good repeatability and reproducibility, and low detection limit, have made the prepared sensor suitable for the analysis of m‐dopa in pharmaceutical and clinical preparations.
Catalytic Adsorptive Stripping Chronopotentiometric Determination of Hexavalent Chromium at a Silver Amalgam Film Electrode of Prolonged Application
Authors: Bobrowski Andrzej , Kapturski Paweł , Zarębski Jerzy
Published: August 2011

The paper reports on the application of stripping chronopotentiometry for the determination of chromium(VI) at a silver‐based amalgam film electrode. It is the first attempt to apply such a detection system for the speciation of chromium. The procedure utilized catalytic reduction of nitrate ions induced by the instantaneous chromium(III)‐DTPA complex, accumulated at the electrode surface. The chronopotentiometric step is realized in the constant current mode. Several key parameters, such as the deposition potential, deposition time, nitrate concentration and stripping current were optimized. The detection limit obtained for 15 s of accumulation time was estimated at 0.025 µg/L. The repeatability of the signal was 6.1 %.
Amperometric Sensing Based on Glutathione Protected Au25 Nanoparticles and Their pH Dependent Electrocatalytic Activity
Authors: Kumar S. Senthil , Kwak Kyuju , Lee Dongil
Published: August 2011

We report here the electrochemical behavior of quantum sized glutathione protected Au25 nanoclusters and their use in electrochemical sensing. The Au25 modified electrode was found to show excellent electrocatalytic activity towards the oxidation of ascorbic acid and dopamine over a wide linear range from 0.71 to 44.4 µM. The modified electrode exhibited pH dependent electrocatalytic activity, which was attributed to the consequence of electrostatic attraction/repulsion between the charged Au25 clusters and the charged analytes at different pH. This result demonstrates the feasibility of enhancing the sensing selectivity among the charged analytes by controlling the charges on the clusters.
Standardized Characterization of a Flow Through Microbial Fuel Cell
Authors: Higgins Scott R. , Lau Carolin , Atanassov Plamen , Minteer Shelley D. , Cooney Michael J.
Published: August 2011

Microbial fuel cell research is a relatively new and fast growing field of interdisciplinary effort that has drawn scientists from several disparate disciplines. Consequently, establishing a “common language” regarding the “means and ways” of experimental preparation, data collection and characterization to obtain accurate and comparable figures of merit (describing microbial fuel cell performance) has proven difficult. We present a methodology for comprehensive engineering analysis from inoculation through batch, fed‐batch and finally continuous flow operation, and detail how a modified stack cell design complements this. More, our cell is able to operate near the thermodynamic maximum potential for oxidation of lactate.
Development of an Electrochemical Biosensor for the Rapid Detection of Cholera Toxin Using Air Stable Lipid Films with incorporated Ganglioside GM1
Authors: Nikoleli Georgia‐Paraskevi , Nikolelis Dimitrios P. , Tzamtzis Nikolaos
Published: August 2011

The present work describes the investigations of electrochemical interactions of cholera toxin with stabilized lipid films supported on a methacrylate polymer on a glass fiber filter with incorporated ganglioside GM1 for the development of a biosensor for cholera toxin. The analyte was injected into the flowing streams of a carrier electrolyte solution, the flow of the solution stops for 5 min and an ion current transient was obtained, the magnitude of which is correlated to the toxin concentration with detection limits of 0.06 µM. The method was applied in blood serum samples. Further work is directed to the rapid detection of other toxins used in bioterrorism using this novel ultrathin film technology.
Joint channel‐network coding strategies for networks with low‐complexity relays
Authors: Johnson Sarah J. , Ong Lawrence , Kellett Christopher M.
Published: August 2011

We investigate joint network and channel coding schemes for networks when relay nodes are not capable of performing channel coding operations. Rather, channel encoding is performed at the source node, whereas channel decoding is carried out only at the destination nodes. We examine three different decoding strategies: independent network‐then‐channel decoding, serial network and channel decoding, and joint network and channel decoding. Furthermore, we describe how to implement such joint network and channel decoding using iteratively decodable error correction codes. Using simple networks as a model, we derive achievable rate regions and use simulations to demonstrate the effectiveness of the three decoders. Copyright © 2011 John Wiley & Sons, Ltd.
Effects of bilirubin and sera from jaundiced patients on osteoblasts: Contribution to the development of osteoporosis in liver diseases
Authors: Ruiz-Gaspà Silvia , Martinez-Ferrer Angels , Guañabens Nuria , Dubreuil Marta , Peris Pilar , Enjuanes Anna , de Osaba Maria Jesús Martinez , Alvarez Luisa , Monegal Ana , Combalia Andrés , Parés Albert
Published: August 2011

Low bone formation is considered to be the main feature in osteoporosis associated with cholestatic and end-stage liver diseases, although the consequences of retained substances in chronic cholestasis on bone cells have scarcely been studied. Therefore, we analyzed the effects of bilirubin and serum from jaundiced patients on viability, differentiation, mineralization, and gene expression in the cells involved in bone formation. The experiments were performed in human primary osteoblasts and SAOS-2 human osteosarcoma cells. Unconjugated bilirubin or serum from jaundiced patients resulted in a dose-dependent decrease in osteoblast viability. Concentrations of bilirubin or jaundiced serum without effects on cell survival significantly diminished osteoblast differentiation. Mineralization was significantly reduced by exposure to 50 μM bilirubin at all time points (from −32% to −55%) and jaundiced sera resulted in a significant decrease on cell mineralization as well. Furthermore, bilirubin down-regulated

RUNX2

(runt-related transcription factor 2) gene expression, a basic osteogenic factor involved in osteoblast differentiation, and serum from jaundiced patients significantly up-regulated the

RANKL/OPG

(receptor activator of nuclear factor-κB ligand/osteoprotegerin) gene expression ratio, a system closely involved in osteoblast-induced osteoclastogenesis.

Conclusion:

Besides decreased cell viability, unconjugated bilirubin and serum from jaundiced patients led to defective consequences on osteoblasts. Moreover, jaundiced serum up-regulates the system involved in osteoblast-induced osteoclastogenesis. These results support the deleterious consequences of increased bilirubin in advanced chronic cholestasis and in end-stage liver diseases, resulting in disturbed bone formation related to osteoblast dysfunction. (Hepatology 2011)
A polymorphism that delays fibrosis in hepatitis C promotes alternative splicing of AZIN1 , reducing fibrogenesis
Authors: Paris Andrew J. , Snapir Zohar , Christopherson Cindy D. , Kwok Shirley Y. , Lee Ursula E. , Ghiassi-Nejad Zahra , Kocabayoglu Peri , Sninsky John J. , Llovet Josep M. , Kahana Chaim , Friedman Scott L.
Published: August 2011

Among several single-nucleotide polymorphisms (SNPs) that correlate with fibrosis progression in chronic HCV, an SNP in the antizyme inhibitor (AzI) gene is most strongly associated with slow fibrosis progression. Our aim was to identify the mechanism(s) underlying this observation by exploring the impact of the AzI SNP on hepatic stellate cell (HSC) activity. Seven novel AZIN1 splice variants (“SV2-8”) were cloned by polymerase chain reaction from the LX2 human HSC line. Expression of a minigene in LX2 containing the

AZIN1

slow-fibrosis SNP yielded a 1.67-fold increase in AZIN1 splice variant 2 (AZIN1 SV2) messenger RNA (mRNA) (

P

= 0.05). In healthy human leukocytes, the SNP variant also correlated with significantly increased SV2 mRNA. Cells (293T) transfected with short hairpin RNA (shRNA) complementary to the exonic splicing chaperone SRp40 expressed 30% less SRp40 (

P

= 0.044) and 43% more AzI SV2 (

P

= 0.021) than control shRNA-expressing cells, mimicking the effect of the sequence variant. LX2 cells transfected with

AZIN1

full-length complementary DNA expressed 35% less collagen I mRNA (

P

= 0.09) and 18% less α-smooth muscle actin mRNA (

P

= 0.09). Transient transfection of AZIN1 SV2 complementary DNA into LX2 cells reduced collagen I gene expression by 64% (

P

= 0.001) and α-smooth muscle actin by 43% (

P

= 0.005) compared to vector-transfected controls, paralleling changes in protein expression. Both AZIN1 and AZIN-SV2 mRNAs are detectable in normal human liver and reduced in HCV cirrhotic livers. The AZIN1-SV2 acts via a polyamine-independent pathway, as it neither interacts with antizyme nor affects the ability of AZIN1 lacking this variant to neutralize antizyme.

Conclusion:

An SNP variant in the

AZIN1

gene leads to enhanced generation of a novel alternative splice form that modifies the fibrogenic potential of HSCs. (Hepatology 2011)
Impact of seasonal variations in hydrological stresses and spatial variations in geologic conditions on a TCE plume at an industrial complex in Wonju, Korea
Authors: Yang Jae‐Ha , Lee Kang‐Kun , Clement T. Prabhakar
Published: August 2011

Spatial and temporal variations in a trichloroethylene (TCE) plume at an industrial complex in Wonju, Korea, were examined based on hydrogeological data and seven rounds of groundwater quality data collected over a year. The site has considerable vertical heterogeneities; the top layer of soil is covered by impermeable paving material at several locations, followed by a series of reclaimed or residual soil layers, and with weathered rocks to the crystalline biotite granite at the bottom. Areal heterogeneity in the surface conditions plays an important role in controlling groundwater recharge. The heterogeneity structure is influenced by complex surface conditions paved with asphalt and concrete. Owing to the presence of limited recharge area and concentrated summer precipitation events, the effects of seasonal variations on groundwater hydraulics tend to diminish with distance from the recharge area. This result was established by analysing the influence of the contrasting surface recharge conditions between the near‐source zone and the far zone, and the seasonally concentrated precipitation on the transport patterns of a TCE plume. In addition, variations in the plume's downstream contaminant flux levels were also analysed along a transect line near the source zone. The results show that the general tendency of the TCE plume contaminant concentration and mass discharges were reproducible if we account for seasonal recharge variations and the associated changes in the groundwater level. During recharge events, the TCE concentration variations appear to be influenced by leaching of the residual dense non‐aqueous‐phase liquid (DNAPL) TCE trapped in the unsaturated zone. This result shows that seasonal variations in contaminant plume near the source zone is inevitable at this site, and that these variations indicate the presence of residual DNAPL at or above the water table, at least in some isolated locations. Copyright © 2011 John Wiley & Sons, Ltd.
Linking spatial patterns of perched groundwater storage and stormflow generation processes in a headwater forested catchment
Authors: Ali Geneviève A. , L'Heureux Caroline , Roy André G. , Turmel Marie‐Claude , Courchesne François
Published: August 2011

This study examined hydropedological patterns and storage–discharge relationships towards catchment process understanding at a small forested site, the Hermine (Laurentians, Quebec, Canada). The catchment is characterized by a steep surface topography and a shallow, irregular, low‐permeability soil layer (LPSL), thus offering two possible main hydrologic drivers for runoff generation and routing. Using spatially detailed topographic data of the soil surface and the LPSL, water table levels measured at 94 locations on 50 occasions were expressed as 5 perched groundwater (PGW) storage variables: (i) a binary index illustrating the presence/absence of surface water, (ii) a soil saturation deficit, (iii) a water table elevation above the LPSL, (iv) a classification of sites as being in a dry, filling or spilling subsurface depression, and (v) a water table elevation above an underlying filled subsurface depression. The most common proxies for PGW storage, namely the saturation deficit and the location of surface saturated areas, were least appropriate to portray the Hermine catchment dynamics. Patterns of PGW storage were initially important during a rainstorm to trigger a response at the outlet but then remained unchanged even though streamflows continued to increase up to a higher order of magnitude. Hydraulically limited water tables were shown to exist in some areas, thus hinting towards the coexistence of rapid lateral preferential flow and slower subsurface flow. Most importantly, discontinuous storage–discharge relationships at the point‐scale combined into continuous relationships at the catchment‐scale, a result which can be seen as an emergent property of the Hermine catchment. Copyright © 2011 John Wiley & Sons, Ltd.
The seismic signatures of the surge wave from the 2009 Xiaolin landslide‐dam breach in Taiwan
Authors: Feng Zheng‐yi
Published: August 2011

The catastrophic Xiaolin landslide occurred on 9 August 2009, after Typhoon Morakot struck Taiwan. This landslide formed a dam that subsequently breached, burying and flooding the village of Xiaolin. Seismic signals were induced by the landslide and dam breaching and recorded at the Jiaxian broadband seismic station in Taiwan. The time‐frequency spectra for the data from this station were analysed to extract the seismic characteristics of the landslide and to deduce the timing of processes associated with the landslide dam‐break flooding. The duration of the river blockage, the time of the dam breach, the duration of the surge wave and the mean speed of the surge wave were estimated, and the hydrological implications of the flood behaviour were interpreted. The spectral characteristics of the different stream discharges were also studied. Stream water level/discharge is closely related to the frequency of the seismic signals. The broadband stations are particularly useful for flood monitoring due to their ability to continuously record measurements and their high sensitivity. Copyright © 2011 John Wiley & Sons, Ltd.
Supramolecular Assembly and Binding in Aqueous Solution: Useful Tips Regarding the Hofmeister and Hydrophobic Effects
Authors: Gibb Bruce C.
Published: August 2011

The self‐assembly of structurally discrete entities, and supramolecular chemistry in general, continues to expand into the aqueous realm. To do so, however, requires a firm understanding of the properties of aqueous solution, and how these “change the rules” for binding and assembly relative to organic solvents. In this mini‐review we highlight the state‐of‐the‐art understanding of the supramolecular properties of water, and how these influence the design of hosts and self‐assembling systems.
Accurate prediction of the enthalpies of formation for xanthophylls
Authors: Lii Jenn‐Huei , Liao Fu‐Xing , Hu Ching‐Han
Published: August 2011

This study investigates the applications of computational approaches in the prediction of enthalpies of formation (ΔHf) for C‐, H‐, and O‐containing compounds. Molecular mechanics (MM4) molecular mechanics method, density functional theory (DFT) combined with the atomic equivalent (AE) and group equivalent (GE) schemes, and DFT‐based correlation corrected atomization (CCAZ) were used. We emphasized on the application to xanthophylls, C‐, H‐, and O‐containing carotenoids which consist of ∼ 100 atoms and extended π‐delocaization systems. Within the training set, MM4 predictions are more accurate than those obtained using AE and GE; however a systematic underestimation was observed in the extended systems. ΔHf for the training set molecules predicted by CCAZ combined with DFT are in very good agreement with the G3 results. The average absolute deviations (AADs) of CCAZ combined with B3LYP and MPWB1K are 0.38 and 0.53 kcal/mol compared with the G3 data, and are 0.74 and 0.69 kcal/mol compared with the available experimental data, respectively. Consistency of the CCAZ approach for the selected xanthophylls is revealed by the AAD of 2.68 kcal/mol between B3LYP‐CCAZ and MPWB1K‐CCAZ. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Synthesis of a stable‐isotope‐labeled biotinylated pentasaccharide conjugate (EP217609), a dual‐effect anticoagulant drug
Authors: Richard Sébastien , El Hadri Ahmed , Goedheijt Marcel Schreuder , Heisen Michel , Vader Jan , Wiegerinck Peter , Petitou Maurice
Published: August 2011

EP217609 is a neutralizable dual‐effect anticoagulant under clinical investigation in cardiopulmonary bypass during cardiac surgery. Stable‐isotope‐labeled EP217609 was synthesized as an internal standard for mass spectrometry in support of bioassays. EP217609 was obtained in six steps starting from three building blocks in an overall yield of 42%, with a chemical purity of >99%. Thus, coupling between the N‐protected labeled biotin‐lysine 4, prepared in three steps from [13C,15N]‐l‐lysine 2, and the pentasaccharide‐spacer‐amine 6 was first performed. Removal of the Cbz protective group to 8 followed by coupling of the activated peptidomimetic building‐block 10 gave the immediate precursor of EP217609, which could be obtained after catalytic hydrogenolysis of 1,2,4‐oxadiazol‐5(2H)‐one into amidine.
Lactosaminated N‐succinyl‐chitosan as a liver‐targeted carrier of 99mTc in vivo for nuclear imaging and biodistribution
Authors: Hawary Dalia L. , Motaleb Mohamed A. , Farag Hamed , Guirguis Osiris W. , Elsabee Maher Z.
Published: August 2011

Lactosaminated N‐succinyl‐chitosan (LNSC), a water‐soluble biodegradable derivative of chitosan, was prepared, characterized, and investigated for nuclear imaging and body distribution. The labeling efficiency of LNSC was examined with 99mTc, and the obtained complex was used as liver‐targeted delivery system in vivo for nuclear imaging, and its biodistribution within the body was studied. The labeling efficiency with 99mTc was investigated for time of reaction, effect of substrate amount, effect of stannous chloride (SnCl2) concentration, and effect of the pH of the reaction mixture, in order to approach the optimum condition for labeling technique. It was found that the maximum yield for labeling of 2.5‐mg 99mTc‐LNSC was 96.9% when 50 µg of SnCl2 was used at pH 3.5–5, at room temperature and 5‐min reaction time. An in vivo biodistribution study of radiolabeled LNSC was carried out in female Wistar rats, and the body distribution profile was recorded by gamma scintigraphy. The biodistribution of 99mTc‐labeled LNSC (99mTc‐LNSC) in each organ was calculated as a percentage of the injected dose per gram of tissue (%ID/g). 99mTc‐LNSC was shown to be a highly potential approach for liver imaging. Moreover, the rapid excretion of LNSC through the kidneys suggests that water‐soluble chitosan derivatives are good carriers of radioactive elements that do not accumulate in the body. The results indicate that the easy and inexpensive extraction, and thus the ready availability, of chitosan and its derivatives makes them potentially useful for applications in scintigraphic imaging.
A method for preparing sodium acrylate‐d3, a useful and stable precursor for deuterated acrylic monomers
Authors: Yang Jun , Hong Kunlun , Bonnesen Peter V.
Published: August 2011

A convenient and economical method for converting propiolic acid to sodium acrylate‐d3 is described. Successive D/H exchange of the alkyne proton of sodium propiolate (prepared from propiolic acid) using D2O affords sodium propiolate‐d having up to 99 at.% D. Sodium propiolate‐d can be partially reduced to sodium acrylate‐d3 with 90% conversion and 89% yield using D2 and the Lindlar catalyst, with control of reaction parameters to maximize conversion while minimizing over‐reduction. Copyright © 2011 John Wiley & Sons, Ltd.
Salivary gland function evaluated by diffusion‐weighted MR imaging with gustatory stimulation: Preliminary results
Authors: Kato Hiroki , Kanematsu Masayuki , Toida Makoto , Kawaguchi Tomoko , Shibata Toshiyuki , Kajita Kimihiro , Hoshi Hiroaki
Published: August 2011

Purpose:

To evaluate the usefulness of diffusion‐weighted MR imaging using a transient gustatory stimulation method in patients with xerostomia.

Materials and Methods:

Ten consecutive patients complaining of xerostomia and 10 healthy volunteers were examined with a 1.5 Tesla (T) MR unit. All study subjects completed a questionnaire, and patients underwent salivary gland scintigraphy and Saxon test. T1‐, T2‐, and diffusion‐weighted MR images were obtained before stimulation. One minute after gustatory stimulation with lemon juice, diffusion‐weighted sequence was repeated 9 times. A radiologist evaluated signal intensities and apparent diffusion coefficients (ADCs) in parotid and submandibular glands. ADC increase rate (IR) and times to maximum ADC (Tmax) were assessed.

Results:

IRs showed a moderate positive correlation with washout rates by scintigraphy for parotid (r = 0.554, P < 0.05) and submandibular (r = 0.617, P < 0.01) glands. Furthermore, Tmax values of parotid and submandibular glands were significantly higher in patients (420 ± 226 and 357 ± 232 s, respectively) than in volunteers (181 ± 68 and 200 ± 75 s, respectively) (P < 0.01).

Conclusion:

Our preliminary results indicate that diffusion‐weighted MR imaging using a transient gustatory stimulation method is potentially useful for evaluating patients with xerostomia. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Diffusion‐weighted imaging of the healthy pancreas: Apparent diffusion coefficient values of the normal head, body, and tail calculated from different sets of b‐values
Authors: Schoennagel Bjoern P. , Habermann Christian R. , Roesch Magdalena , Hahne Jasmin D. , Arndt Christiane , Kleibeler Laura , Petersen Kay U. , Graessner Joachim , Adam Gerhard , Herrmann Jochen
Published: August 2011

Purpose:

To evaluate differences in apparent diffusion coefficient (ADC) values between head, body, and tail regions and the impact of sets of b‐values used in diffusion weighted imaging (DWI) of the normal pancreas.

Materials and Methods:

In 51 healthy volunteers echo‐planar DWI of the pancreas was prospectively performed with b‐values of 50, 400, and 800 s/mm2. All four possible combinations of b‐values were used to calculate ADC values in a total of 587 regions in the pancreas head, body, and tail regions. Dependency of ADC values on the anatomical regions and on the applied sets of b‐values was calculated using multivariate analysis of variance (ANOVA).

Results:

Mean ADC values differed significantly between the anatomical regions with the lowest values measured in the pancreatic tail (head 1.13 ± 0.20, body 1.05 ± 0.20, and tail 0.94 ± 0.18 × 10−3 mm2/s; P < 0.05). ANOVA showed no dependency of ADC values on the sets of b‐values used.

Conclusion:

ADC values differed significantly between the pancreatic head, body, and tail region, with decreasing ADC values toward the tail. Cautious interpretation of DWI results with adjusted, normalized values adapted to the anatomical region seems advisable. The knowledge of such differences may enhance the method's capability to differentiate between different pancreatic pathologies. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
On‐tissue chemical derivatization of 3‐methoxysalicylamine for MALDI‐imaging mass spectrometry
Authors: Chacon Almary , Zagol‐Ikapitte Irene , Amarnath Venkataraman , Reyzer Michelle L. , Oates John A. , Caprioli Richard M. , Boutaud Olivier
Published: August 2011

MALDI‐imaging mass spectrometry (IMS) has been shown to be a powerful tool to study drug distributions in organ tissue as well as whole animal bodies. Nevertheless, not all drugs are amenable to MALDI while others may be limited by poor sensitivity poor sensitivity. The use of chemical derivatization to improve detection of small molecules by mass spectrometry techniques is well documented. To our knowledge, however, this approach has not been applied to direct tissue analysis of small organic molecules. In this manuscript, we demonstrate the use of on‐tissue chemical derivatization of a small organic molecule, 3‐methoxysalicylamine (3‐MoSA) a scavenger of γ‐ketoaldehydes. Derivatization of 3‐MoSA with 1,1′‐thiocarbonyldiimidazole (TCDI) results in an oxothiazolidine derivative which is detected with much greater sensitivity by MALDI than 3‐MoSA itself. TCDI treatment of tissue from mice dosed with 3‐MoSA allowed images to be obtained showing its spatial distribution as well as its pharmacokinetic profile in different organs. These images correlated well with results obtained from HPLC‐MS/MS analyses of the same tissues. These results provide proof‐of‐concept that on‐tissue chemical derivatization can be used to improve detection of a small organic molecule by MALDI‐IMS. Copyright © 2011 John Wiley & Sons, Ltd.
Clinical features and molecular epidemiology of rotavirus and norovirus infections in Libyan children
Authors: Abugalia Mohamed , Cuevas Luis , Kirby Andrew , Dove Winifred , Nakagomi Osamu , Nakagomi Toyoko , Kara Majdi , Gweder Rabia , Smeo Mohamed , Cunliffe Nigel
Published: August 2011

Rotaviruses and noroviruses are leading viral causes of diarrhoea in children. A cross‐sectional study was undertaken among children aged <5 years with acute gastroenteritis at Al‐Jala Children's Hospital, Tripoli, Libya, from October 2007 to September 2008. Of 1,090 fecal samples collected, 260 from inpatients and 830 from outpatients, all inpatients and approximately a third of outpatients, selected systematically, were investigated for rotavirus and norovirus infection by ELISA and real‐time RT‐PCR, respectively. Of 520 fecal samples examined (inpatients = 260, outpatients = 260), 164 (31.5%) had rotavirus and 91 (17.5%) had norovirus detected. Rotavirus was identified more often among inpatients than outpatients (35.8% vs. 27.3% respectively, P = 0.038). Norovirus was detected more commonly among outpatients than inpatients (21.2% vs. 13.8% respectively, P = 0.028). The peak incidence of infection with both viruses was among children aged between 6 and 11 months. The number of rotavirus cases was highest between November and June with a peak detection rate of 50% in January. Norovirus occurred most commonly from May through August with a peak detection rate of 47% in August. The most prevalent rotavirus genotypes were P[8], G9 (n = 116, 65.9%), followed by P[8],G1 (n = 49, 27.8%); a single P[9], G3 strain was detected. There were seven distinct electropherotypes among the G9 strains and all belonged to VP7 Lineage III. Among 91 noroviruses identified, 90 were genogroup II. Of 26 genogroup II noroviruses examined, all were genotype GII.4. Rotaviruses and noroviruses are both important causes of gastrointestinal infection among young children in Libya. J. Med. Virol. 83:1849–1856, 2011. © 2011 Wiley‐Liss, Inc.
Fatal type 7 adenovirus associated with human bocavirus infection in a healthy child
Authors: Heydari Hosein , Mamishi Setare , Khotaei Ghamar‐Taj , Moradi Sara
Published: August 2011

Adenovirus is a common cause of acute upper respiratory tract infection and rarely causes respiratory failure or septic shock in immunocompetent patients. Severe disease is confined to immunocompromised patients. Human bocavirus (HBoV) is known as the fourth most common virus in respiratory samples from healthy subjects. In patients with respiratory complaints, it can be found alone or, more often, in combination with other viruses known to cause respiratory complaints. A well‐documented fatal case of HBoV and adenovirus pneumonia with myocarditis in an immunocompetent child is described. J. Med. Virol. 83:1762–1763, 2011. © 2011 Wiley‐Liss, Inc.
Respiratory viruses involved in influenza‐like illness in a Greek pediatric population during the winter period of the years 2005–2008
Authors: Pogka Vasiliki , Kossivakis Athanasios , Kalliaropoulos Antonios , Moutousi Afroditi , Sgouras Dionyssios , Panagiotopoulos Takis , Chrousos George P. , Theodoridou Maria , Syriopoulou Vassiliki P. , Mentis Andreas F.
Published: August 2011

Viruses are the major cause of pediatric respiratory tract infection and yet many suspected cases of illness remain uncharacterized. This study aimed to determine the distribution of several respiratory viruses in children diagnosed as having influenza‐like illness, over the winter period of 2005–2008. Molecular assays including conventional and real time PCR protocols, were employed to screen respiratory specimens, collected by clinicians of the Influenza sentinel system and of outpatient pediatric clinics, for identification of several respiratory viruses. Of 1,272 specimens tested, 814 (64%) were positive for at least one virus and included 387 influenza viruses, 160 rhinoviruses, 155 respiratory syncytial viruses, 95 adenoviruses, 81 bocaviruses, 47 parainfluenza viruses, 44 metapneumoviruses, and 30 coronaviruses. Simultaneous presence of two or three viruses was observed in 173 of the above positive cases, 21% of which included influenza virus and rhinovirus. The majority of positive cases occurred during January and February. Influenza virus predominated in children older than 1 year old, with type B being the dominant type for the first season and subtypes A/H3N2 and A/H1N1 the following two winter seasons, respectively. Respiratory syncytial virus prevailed in children younger than 2 years old, with subtypes A and B alternating from year to year. This is the most comprehensive study of the epidemiology of respiratory viruses in Greece, indicating influenza, rhinovirus and respiratory syncytial virus as major contributors to influenza‐like illness in children. J. Med. Virol. 83:1841–1848, 2011. © 2011 Wiley‐Liss, Inc.
Prevalence of human papillomavirus genotypes and associated cervical squamous intraepithelial lesions in HIV‐infected women in Botswana
Authors: MacLeod Iain J. , O'Donnell Belinda , Moyo Sikhulile , Lockman Shahin , Shapiro Roger L. , Kayembe Mukendi , van Widenfelt Erik , Makhema Joseph , Essex M. , Wester Carolyn
Published: August 2011

Human papillomaviruses (HPV) constitute one of the most prevalent sexually transmitted infections and are the etiological agents for invasive cervical cancer, the predominant cancer among women in Botswana. However, the prevalence of HPV genotypes in Botswana has yet to be reported.

One hundred thirty‐nine endocervical swabs were taken at baseline from HIV‐1 infected, HSV‐2 seropositive women enrolled in a longitudinal cohort study designed to assess the influence of herpes simplex virus‐2 (HSV‐2) infection on genital tract shedding of HIV‐1. Extracted DNA was evaluated for the presence of low‐risk and high‐risk HPV using the Roche Linear Array.

Genotyping identified HPV in 95 of 139 women of which 61/95 were infected with high‐risk HPV and 56/95 with low‐risk HPV. The median number of genotypes was 2 (IQR: 1–4). The most prevalent HPV genotype in HIV‐infected women was HPV 58. Abnormal cervical cytology was detected in 87/127 women and was associated with contemporaneous HPV infection (RR = 1.43, 95% CI: 1.05–1.93; P = 0.02).

HPV prevalence was high among HIV‐infected women with infection by multiple genotypes being widespread. The associations attributed to specific oncogenic HPV subtypes and cervical squamous intraepithelial lesions presented here provide critical information to inform future vaccine policy within Botswana. J. Med. Virol. 83:1689–1695, 2011. © 2011 Wiley‐Liss, Inc.
Confirmation of an association between single nucleotide polymorphisms in the VDR gene with respiratory syncytial virus related disease in South African Children
Authors: Kresfelder T.L. , Janssen R. , Bont L. , Venter M.
Published: August 2011

Respiratory syncytial virus is a leading cause of lower respiratory tract infection in infants. Disease severity has been linked to host immune responses and polymorphisms in genes associated with innate immunity. A large‐scale genetics study of single nucleotide polymorphisms (SNPs) in children in the Netherlands identified SNPs in the vitamin D receptor (VDR) and JUN genes which have a strong association with an increased risk of developing bronchiolitis following the first respiratory syncytial virus (RSV) infection. The Toll‐like receptor 4 (TLR4) gene has two SNPs which have been associated previously with RSV disease severity in various populations. The aim of this study was to determine if these SNPs may be associated with RSV disease in African children in South Africa. RSV patient (n = 296) and control (n = 113) groups were established (median ages: 3 and 3.5 months) and DNA extracted from the collected specimens. Real‐time polymerase chain reaction using hydrolysis probes was used to screen for SNPs in the VDR (Thr1Meth; rs10735810), TLR4 (Asp299Gly; rs4986790 and Thr399Ile; rs4986791) and JUN (c.750G/A; rs11688) genes. Carriers of the VDR (Thr1Meth) SNP minor T allele were more prone to RSV disease than individuals in the control group. The TLR4 (Asp299Gly), TLR4 (Thr399Ile), and JUN (c.750G/A) SNPs showed no significant association with RSV disease. It is concluded that children carrying the minor T allele of the VDR (Thr1Meth) SNP may be predisposed to RSV disease, as this SNP was identified as a risk factor for severe RSV disease in South African children, confirming the findings in the Netherlands. J. Med. Virol. 83:1834–1840, 2011. © 2011 Wiley‐Liss, Inc.
Acute West Nile virus neuroinvasive infections: Cross‐reactivity with dengue virus and tick‐borne encephalitis virus
Authors: Papa Anna , Karabaxoglou Dimitra , Kansouzidou Athina
Published: August 2011

Cross‐reactions in serology are common among flaviviruses. During the outbreak of West Nile virus (WNV) infections in Greece in 2010, WNV IgM‐positive serum and cerebrospinal fluid samples were tested for the presence of IgM and IgG antibodies against Dengue virus (DENV) and tick‐borne encephalitis virus. Higher cross‐reactivity was observed in IgM antibodies between WNV and DENV; however, the index of the WNV antibodies was in all cases higher than that of the DENV antibodies. There is a need for caution when evaluating serologic results of flaviviral infections, while efforts have to be focused on the development of diagnostic assays with increased specificity. J. Med. Virol. 83:1861–1865, 2011. © 2011 Wiley‐Liss, Inc.
High prevalence of BK Polyomavirus Sequences in Human Papillomavirus‐16‐Positive Precancerous Cervical Lesions
Authors: Comar Manola , Bonifacio Daniela , Zanconati Fabrizio , Di Napoli Michela , Isidoro Erica , Martini Fernanda , Torelli Lucio , Tognon Mauro
Published: August 2011

High‐ and low‐grade cervical lesions were analyzed for the presence of polyomavirus (PYV) and human papillomavirus (HPV) sequences. In precancerous cervical lesions, the overall prevalence of PYV sequences was 44% (41/93). Specifically, among the PYV‐positive samples, 83% (34/41) tested positive for BK polyomavirus (BKV) sequences, whereas 17% (7/41) were positive for JC‐virus. None of the samples were positive for simian virus 40. The presence of BKV DNA in high‐grade squamous intraepithelial lesions was confirmed by in situ PCR. BKV sequences were detected more frequently in high‐grade squamous intraepithelial lesions, together with the genotype HPV‐16. The association of BKV with precancerous cervical lesions suggests that this polyomavirus participates with HPV‐16 in the cell transformation process. Alternatively, BKV might multiply better in HPV‐16‐positive cells from precancerous cervical lesions than in HPV‐16‐negative cells. J. Med. Virol. 83:1770–1776, 2011. © 2011 Wiley‐Liss, Inc.
Genotype‐specific effects on left ventricular function in parvovirus B19‐positive patients with dilated cardiomyopathy
Authors: Ruppert Volker , Meyer Thomas , Balbach Anna , Richter Anette , Müller Hans‐Helge , Maisch Bernhard , Pankuweit Sabine ,   on behalf of the German Heart Failure Network
Published: August 2011

Genotype‐specific effects of parvovirus B19 (B19V) infections on left ventricular function in patients with dilated cardiomyopathy (DCM) have not been investigated so far. In this prospective clinical study, the prevalences of B19V genotypes in endomyocardial biopsies from patients presenting with inflammatory heart disease and DCM were determined. A total of 139 consecutive patients were included in the study; among them 53 patients were diagnosed as DCM. Among the total study cohort, B19V DNA was detected in 65 study participants (46.8%). Genotyping of the B19V genomes in the total cohort identified genotype 1 in 38 samples (27.3%), genotype 2 in 25 samples (18.0%), and genotype 3 in only two patients (1.4%). During an average follow‐up period of 8 months left ventricular ejection fraction (LVEF) improved significantly both in B19V‐positive (7.1 ± 13.8%, n = 17, P = 0.038) as well as B19V‐negative patients with DCM (9.5 ± 13.9%, n = 20, P = 0.017). However, mean LVEF improved only in patients with genotype 1 (11.0 ± 14.4%, n = 7), whereas it even decreased in patients with genotype 2 (−6.2 ± 6.3%, n = 5, P = 0.033). These data from a small sample of patients diagnosed as DCM suggested that myocardial function during short‐time follow‐up differed between genetic variants of B19V. Patients with genotype 1 were on average younger than genotype 2 and appeared to be more prone to a beneficial course of left ventricular function than patients with genotype 2. Future studies with larger sample sizes and longer follow‐up periods will be required to confirm this observation. J. Med. Virol. 83:1818–1825, 2011. © 2011 Wiley‐Liss, Inc.
Co‐circulation HIV‐1 subtypes B, C, and CRF31_BC in a drug‐naïve population from Southernmost Brazil: Analysis of primary resistance mutations
Authors: de Medeiros Rúbia Marília , Junqueira Dennis Maletich , Matte Maria Cristina Cotta , Barcellos Nêmora Tregnago , Chies José Artur Bogo , Matos Almeida Sabrina Esteves
Published: August 2011

In Southernmost Brazil HIV‐1 subtypes B, C, and CRF31_BC co‐circulates and, since 1996 with the implementation of free access to highly active antiretroviral treatment (HAART), this epidemic is under a quite characteristic selective pressure. The profile of mutations and polymorphisms in the protease (PR) and reverse transcriptase (RT) genes of HIV‐1 from untreated patients living in Porto Alegre, Southernmost Brazil were evaluated in order to identify the subtypes and circulating drug resistant genotypes. Blood samples from 99 HIV‐1 positive drugs‐naïve patients were collected from 2006 to 2007 in Porto Alegre, Brazil. HIV PR and RT genes were amplified, sequenced, and subtyped. The HIV‐1 genotyping was performed by partial sequence analysis of the pol in the HIV Drug Resistance Database of Stanford University. Phylogenetic analyses allowed to classify the HIV samples according to their subtypes: B (26.2%), C (39.4%), F (1.1%), CRF31_CB (19.2%), and URF (14.1%). Eight (8.1%) samples showed primary resistance mutations according to the Calibrated Population Resistance tool based in the 2009 Surveillance Drug Resistance Mutation list. Two samples presented resistance mutations to PI, three NRTI and three NNRTI. There was no significant association between presence of resistant genotypes and subtypes, but resistance mutations seem to be less frequent in the subtype C. In addition, this study describes for the first time the mutational profile of CRF31_BC to PI, NRTI, and NNRTI. Genetic analyses of HIV‐1 from naïve patients are a promising and important method for surveillance of HIV infection. J. Med. Virol. 83:1682–1688, 2011. © 2011 Wiley‐Liss, Inc.
Human metapneumovirus in patients with respiratory tract infection in Kuwait
Authors: Al‐Turab Mariam , Chehadeh Wassim , Al‐Mulla Fahd , Al‐Nakib Widad
Published: August 2011

Human metapneumovirus (hMPV) has been recognized as an important cause of respiratory tract infections in all age groups and in all geographical area. The role of hMPV in causing respiratory tract infections in Kuwait was not yet investigated. The aim of this study was to determine the prevalence of hMPV infection in Kuwait among patients with respiratory tract infection with respect to other respiratory viruses. During January–December 2009, 460 respiratory samples from 388 patients with respiratory tract infection were collected from different hospitals. They were tested for hMPV RNA by real‐time PCR, and for other respiratory viruses by conventional PCR. Out of 388 patients, 110 (28%) were positive for viral respiratory infections; 21 (5.4%) were positive for hMPV, 29 (7.5%) were positive for rhinovirus, 13 (4%) were positive for respiratory syncytial virus, and 10 (3%) were positive for adenovirus. Most (n = 19, 90.5%) of hMPV‐positive patients were admitted to the intensive care unit, 76% of them were of age 2 years and below, and 24% of age 59 years and above. All hMPV‐positive elderly patients had pneumonia while 50% of hMPV‐positive infants had bronchopneumonia. Children with hMPV/rhinovirus co‐infection (n = 3, 1%) had recurrent chest infection and frequent intensive care unit admission. The hMPV infection was mostly detected between December and May, and genotype B was more prevalent than genotype A. This is the first study demonstrating the prevalence of hMPV infection in Kuwait, and suggests that hMPV infection is prevalent in infants and elderly patients with lower respiratory tract infection. J. Med. Virol. 83:1811–1817, 2011. © 2011 Wiley‐Liss, Inc.