bluuebunny/crossref_metadata_2025 huggingface dataset:
Room Temperature Ammonia Gas Sensing Using Mixed Conductor based TEMPOS Structures
Authors: Saroch Mamta , Srivastava Sunita , Fink Dietmar , Chandra Amita
Published: October 2008

The current/voltage characteristics of mixed (ion+electron) conductor-based ‘TEMPOS’ (Tunable Electronic Material with Pores in Oxide on Silicon) structures are reported. TEMPOS are novel electronic MOS-like structures having etched swift heavy ion tracks (i.e., nanopores) in the dielectric layer filled with some conducting material. The three contacts (two on top and one on the bottom), which resemble the classical bipolar or field effect transistor arrangements are, in principle, interchangeable when the overall electrical resistance along the tracks and on the surface are similar. Consequently, three configurations are obtained by interchanging the top contacts with the base contact in electronic circuits. The current/voltage characteristics show a diode like behaviour. Impedance measurements have been made for TEMPOS structures with tracks filled with ion conductors and also mixed conductors to study the ammonia sensing behaviour. The impedance has been found to be a function of frequency and magnitude of the applied signal and concentration of the ammonia solution. This is attributed to the large number of charge carriers (here protons) available for conduction on exposure to ammonia and also to the large surface to volume ratio of the polymer composites embedded in the ion tracks. The measurement of both, the real and imaginary parts of impedance allows one to enhance the detection sensitivity greatly.
Thermogravimetric approach for determining the degree of conversion in radiation‐polymerized DADMAC
Authors: Francis Sanju , Varshney Lalit , Mitra Debasish , Sabharwal Sunil
Published: October 2008

The degree of conversion of the monomer diallyldimethylammonium chloride (DADMAC) to its polymer, poly(DADMAC), was determined using dynamic thermogravimetry (TG). DADMAC solution was exposed to different radiation doses, and the degree of conversion of the monomer to the polymer was determined from a calibration plot generated previously from solutions containing known monomer–polymer ratios. The concentration of monomer and polymer in the mixture was estimated by measuring the weight loss corresponding to the steps involved in the thermograms. By employing the method, polymerization of DADMAC as a function of irradiation dose was studied. The degree of conversion of DADMAC increases considerably during the initial stages of irradiation, up to a dose of 40 kGy, after which the increase in conversion is not very significant. To validate the method, the degree of conversion was also determined by classical gravimetry, and the results were found to be in good agreement. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Voltammetric studies of dendrimer multilayers: Layer‐by‐layer assembly of metal‐peptide dendrimers multilayers
Authors: Appoh Francis E. , Kraatz Heinz‐Bernhard
Published: October 2008

Multilayer films of metal‐peptide dendrimers having a ferrocene core were constructed on gold surfaces functionalized with mercaptoundecanoic acid using a layer‐by‐layer approach for film construction. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to monitor the redox activity and stability of these films. The multilayer films showed good stability and exhibited direct electron transfer with the underlying electrode. The specific active surface concentration can be varied by the number of layers, the nature of the dendrimer, and the nature of metal ions used. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and investigation of a new macroporous monolithic material based on an N‐hydroxyphthalimide ester of acrylic acid‐co‐glycidyl methacrylate‐co‐ethylene dimethacrylate terpolymer
Authors: Slabospitskaya M. Yu , Vlakh E. G. , Saprykina N. N. , Tennikova T. B.
Published: October 2008

A macroporous monolithic material based on an N‐hydroxyphthalimide ester of acrylic acid‐co‐glycidyl methacrylate‐co‐ethylene dimethacrylate terpolymer was synthesized by photoinitiated free‐radical polymerization. Several porogenic solvents, such as cyclohexanol, dodecanol, and poly(ethylene glycol)s, were tested to obtain the monolithic material with an optimal pore size allowing unrestricted penetration of large molecule (proteins) into a three‐dimensional porous space. The new monolithic material was covalently bound to an inert surface (glass) directly in the polymerization step, and it was suggested as a solid matrix for the development of new types of three‐dimensional protein microarrays (biochips). A demonstration of the potential of the suggested microarray platform as well as optimization of microarray performance conditions was realized with a model mouse immunoglobulin G/goat anti‐mouse immunoglobulin G affinity pair. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation of ultraviolet‐cured bisphenol A epoxy diacrylate/montmorillonite nanocomposites with a bifunctional, reactive, organically modified montmorillonite as the only initiator via in situ polymerization
Authors: Zang Yangling , Xu Weijian , Liu Guangpeng , Qiu Deyue , Su Shengpei
Published: October 2008

A bifunctional reactive surfactant containing a polymerizable methacrylate group and a benzophenone group, [2‐(methacryloyloxy)ethyl](4‐benzoylbenzyl)dimethylammonium bromide (MDAB), was synthesized to modify montmorillonite (MMT) for the preparation of nanocomposites via photoinduced polymerization. Fourier transform infrared, thermogravimetric analysis, and X‐ray diffraction results indicated that MDAB‐modified MMT was obtained and had intercalated structures. The morphology of the ultraviolet‐cured bisphenol A epoxy diacrylate/MMT nanocomposites prepared from the organically modified MMTs was studied with X‐ray diffraction and transmission electron microscopy, and the results showed an intercalated structure with partial exfoliation for all the samples. Experimental results from thermogravimetric analysis, differential scanning calorimetry, and mechanical property testing also indicated that the thermal and mechanical properties of the ultraviolet‐cured nanocomposites were significantly enhanced by the presence of this bifunctional, reactive, organically modified MMT. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Racemic compound against racemic conglomerate formation: The crystal properties of allylbenzylmethylphenylphosphonium iodide as compared with the nitrogen analogue
Authors: Bredikhin Alexander A. , Eliseenkova Rimma M. , Bredikhina Zemfira A. , Dobrynin Alexey B. , Kostyanovsky Remir G.
Published: October 2008

Although racemic allylbenzylmethylphenylammonium iodide 1b displays spontaneous resolution crystallizing in a homochiral mode as a conglomerate, its phosphonium analogue rac‐2b crystallizes in a heterochiral lattice forming racemic compound in the solid state. The more pronounced conformation freedom for 2b molecules manifests itself by multiple molecules crystallization (Z′ = 3) of (S)‐2b with the three independent molecules having different conformation. Chirality, 2009. © 2008 Wiley‐Liss, Inc.
Successful Conversion of Recent‐onset Atrial Fibrillation by Sequential Administration of up to Three Antiarrhythmic Drugs
Authors: Milicevic Goran , Gavranovic Zeljka , Bakula Miro , Pazur Vedran , Frank Branimir
Published: October 2008

Background

Short‐term conversion attempt of recent‐onset atrial fibrillation (AF) in the emergency room fails too often. Many patients and doctors still prefer pharmacological to electrical solutions in such cases.

Hypothesis

Sequential administration of up to 3 antiarrhythmic drugs of different classes of action (amiodarone, propafenone, and quinidine) may achieve conversion in such patients.

Method

One hundred and forty consecutive patients with recent‐onset AF were transferred to the intensive cardiac care unit after a failed 2‐h conversion attempt in the emergency room. First‐line drug for conversion was continued up to a full dose, and was chosen by AF etiology, or in recurrent AF episodes, empirically. In nonresponders, the failed drug was replaced by a drug of another class, and if the second‐line drug failed it was replaced by a drug of the third‐line. Electrical cardioversion was the final solution for nonresponders.

Results

Sixty percent of patients reached sinus rhythm by the first‐line drug therapy, 34% by the second‐line, and 4% by the third‐line. Seventy‐five percent of patients achieved conversion within 26 h, and 95% of patients achieved conversion within 40 h. Three patients were electrically cardioverted due to hemodynamical instability. Two episodes of Torsade de Pointes ventricular tachycardia were self‐terminated.

Conclusion

Sequential usage of up to 3 antiarrhythmic drugs of different classes of action provides almost complete success in conversion of recent‐onset AF in patients refractory to short‐term conversion attempt in the emergency room. Copyright © 2008 Wiley Periodicals, Inc.
Association Between Serum C‐reactive Protein Elevation and Atrial Fibrillation After First Anterior Myocardial Infarction
Authors: Gedikli Omer , Orem Cihan , Baykan Merih , Karahan Caner , Kucukosmanoglu Mehmet , Sahin Sinan , Korkmaz Levent , Yilmaz Hulya , Celik Sukru
Published: October 2008

Background

Elevated inflammatory markers have been found to correlate with higher risk for cardiac events in patients with acute myocardial infarction (AMI). It has been suggested that C‐reactive protein (CRP) may be involved in the initiation process of atrial fibrillation (AF). However, the role of CRP levels in the occurence of AF in patients with AMI has not been studied. This study investigated whether CRP is a risk factor for AF in patients with acute anterior MI.

Methods

We prospectively evaluated 92 consecutive patients (25 women and 67 men; aged 58 ± 11 y) with a first acute anterior wall MI. Blood samples were obtained at the time of admission to the hospital, and serum CRP levels were measured by an ultrasensitive immunonephelometry method. All patients were evaluated by echocardiography to measure the left ventricular (LV) diameter and functions. All patients were monitored continuously for the detection of AF in the coronary care unit.

Results

Atrial fibrillation occured in 19 (20%) of 92 patients. Univariate analysis showed that patients with AF had an advanced age (63 ± 9.9 versus 56.7 ± 11.7 y, p = 0.034), higher serum CRP level (2.95 ± 2.5 versus 1.71 ± 2.12 mg/dL, p = 0.034), larger LV end‐systolic volume (74 ± 15 versus 63 ± 19, mL p = 0.02), higher LV ejection fraction (31.1 ± 6.2 versus 38.4 ± 10%, p = 0.001), and larger left atrial (LA) diameter (37.1 ± 4.2 versus 34.7 ± 3.3 mm, p = 0.01). In multivariate analysis, only age (odds ratio [OR]: 1.05, 95% confidence interval [CI]: 1–1.11, p = 0.036) and CRP levels (OR: 1.27, 95% CI: 1–1.59, p = 0.039) were independent predictors of AF.

Conclusion

These results suggest that CRP may be a risk factor for AF in patients with acute anterior wall MI. Copyright © 2008 Wiley Periodicals, Inc.
Burden and Timing of Premature Atrial Contractions After Electrical Cardioversion of Persistent Atrial Fibrillation Do Not Predict Its Recurrence
Authors: Poçi Dritan , Abrahamsson Britt‐Marie , Bergfeldt Lennart , Edvardsson Nils
Published: October 2008

Background

The heart is susceptible to recurrence of atrial fibrillation (AF) during the period immediately following conversion to sinus rhythm (SR). It is less clear whether various onset or trigger mechanisms can predict AF recurrence after direct current (DC) cardioversion of persistent AF.

Methods

In this study, 172 patients (117 men), mean age 69 ± 11 y, and with persistent AF underwent elective electrical cardioversion. A detailed analysis was made of the heart rhythm and potential AF trigger mechanisms based on 5 min electrocardiogram (ECG) recordings after conversion.

Results

Of 151 patients discharged in SR, 45 (30%) had a recurrence of AF within 1 wk. Premature atrial contractions (PACs) were the most common potential trigger, occurring on an average of 3/min. They were equally frequent in patients with and without immediate and early reinitiation of AF, and in patients with and without AF recurrence at the 1‐wk follow‐up visit. Other trigger mechanisms were too infrequent to allow conclusions.

Conclusion

Premature atrial contractions were the most common potential trigger mechanism occurring immediately after cardioversion in patients with persistent AF. However, they neither predicted immediate and/or early reinitiations, nor recurrences during the first wk after cardioversion. Copyright © 2008 Wiley Periodicals, Inc.
Systolic Total Narrowing of Left Anterior Descending Coronary Artery and Flow Interruption Secondary to Myocardial Bridge: A Rare Case Report and Review of Literature
Authors: Kacmaz Fehmi , Alyan Omer , Ilkay Erdogan
Published: October 2008

A 33‐y‐old man was admitted to the emergency department with sudden onset of severe substernal chest pain radiating to the left arm and neck. No pathological signs were recorded upon physical examination. The admission electrocardiogram (ECG) recorded during chest pain showed a large anterior wall myocardial infarction. Intravenous (IV) infusion of 1.5 million units of streptokinase over 1 h was initiated. Coronary angiography revealed total narrowing and flow interruption in the midsegment of the left anterior descending (LAD) coronary artery secondary to a myocardial bridge during systole and disappearance with diastole. He was discharged on aspirin (300 mg/d), metoprolol (100 mg/d), enalapril (10 mg twice daily), and atorvastatin (40 mg/d) treatment at the follow‐up period. Copyright © 2008 Wiley Periodicals, Inc.
Wnt/frizzled family members mediate olfactory sensory neuron axon extension
Authors: Rodriguez‐Gil Diego J. , Greer Charles A.
Published: October 2008

The main olfactory epithelium from a postnatal day 4 mouse. Tissue was stained for olfactory marker protein (OMP, red), Wnt‐5a (green) and DRAQ5 (blue). All the mature, OMP‐expressing, olfactory sensory neurons showed Wnt‐5a expression. Wnt‐5a expression appears to cap the nucleus of olfactory sensory neurons apically in a position that is consistent with the localization of the endoplasmic reticulum and Golgi apparatus. J. Comp. Neurol. 511:301–317, 2008. © 2008 Wiley‐Liss, Inc.
Expression of HPV L1 capsid protein in cervical specimens with HPV infection
Authors: Lee Heejeong , Lee Kyung‐Ji , Jung Chan‐Kwon , Hong Jae‐Hwa , Lee Youn‐Soo , Choi Young‐Jin , Lee Kyo‐Young , Park Gyeongsin
Published: October 2008

We tried to investigate the expression rate of human papillomavirus (HPV) L1 capsid protein in uterine cervical specimens and correlate it with the grade of dysplasia, HPV genotype and age of the patients. Among uterine cervical specimens proved to have HPV by DNA genotyping test, eighty cytology‐biopsy matched cases and 22 unmatched cytology specimens were selected. Immunostaining for L1 capsid protein was performed on both cervical smears and tissue sections. The L1 capsid protein was expressed mainly in the nuclei, but occasionally in the cytoplasm of cells located in the superficial layer of squamous epithelium. The immunostaining for L1 capsid protein showed positive reaction in 47 cases (46.1%) of cervical smears and in 10 cases (12.5%) of tissue sections (P = 0.001). Cytologic diagnosis revealed a higher expression rate in LSILs (25/33; 75.8%) than in HSILs and cervical cancers (8/20; 40.0% and 2/5; 40%, respectively) (P = 0.006). In LSILs, cases with low‐risk type HPV showed a higher L1 capsid expression rate than those with the high‐risk type HPV (88.9% vs. 70.8%). The L1 capsid expression rate decreased in the over‐40‐year‐old age group compared to the younger age (49.2% vs. 50.8%). Cytology smears were superior to tissue sections for the detection of L1 capsid protein expression. LSILs and HPV low‐risk group showed higher L1 capsid expression rate than HSILs and HPV high‐risk group, which suggests that L1 capsid expression might be related to a favorable disease biology. Diagn. Cytopathol. 2008. © 2008 Wiley‐Liss, Inc.
Epidermal inclusion cyst: Cytomorphological features and differential diagnosis
Authors: Handa Uma , Chhabra Seema , Mohan Harsh
Published: October 2008

Aspirates from 162 epidermal inclusion cysts (EIC) from 157 patients were analyzed in order to elaborate on specific cytologic features. The most common site involved was the head and neck region (96 cases; 59.2%). The maximum patients were in the 3rd and 4th decades of life. Aspirates from EIC showed a clear background, with high cellularity, and nucleate and anucleate squames. Keratinous material was seen in some cases but the amount was less compared with the cellular elements. In 31 cases, a diagnosis of infected EIC was made on the basis of dense inflammatory infiltrate in addition to the squames. Histopatholgy was available in 56 cases out of which EIC was diagnosed in 45 cases. The remaining 11 cases were dermoid cyst (5 cases), branchial cyst (2 cases), pilomatricoma (2 cases), and sebaceous and thyroglossal cyst (1 case each). Thus, EIC should be differentiated from other squamous cell containing lesions. Diagn. Cytopathol. 2008. © 2008 Wiley‐Liss, Inc.
MAP3Ks as central regulators of cell fate during development
Authors: Craig Evisabel A. , Stevens Mark V. , Vaillancourt Richard R. , Camenisch Todd D.
Published: October 2008

The cytoplasmic serine/threonine kinases transduce extracellular signals into regulatory events that impact cellular responses. The induction of one kinase triggers the activation of several downstream kinases, leading to the regulation of transcription factors to affect gene function. This arrangement allows for the kinase cascade to be amplified, and integrated according to the cellular context. An upstream mitogen or growth factor signal initiates a module of three kinases: a mitogen‐activated protein (MAP) kinase kinase kinase (MAPKKK; e.g., Raf) that phosphorylates and activates a MAP kinase kinase (MAPKK; e.g., MEK) and finally activation of MAP kinase (MAPK; e.g., ERK). Thus, this MAP3K‐MAP2K‐MAPK module represents critical effectors that regulate extracellular stimuli into cellular responses, such as differentiation, proliferation, and apoptosis all of which function during development. There are 21 characterized MAP3Ks that activate known MAP2Ks, and they function in many aspects of developmental biology. This review summarizes known transduction routes linked to each MAP3K and highlights mouse models that provide clues to their physiological functions. This perspective reveals that some of these MAP3K effectors may have redundant functions, and also serve as unique nexus depending on the context of the signaling pathway. Developmental Dynamics 237:3102–3114, 2008. © 2008 Wiley‐Liss, Inc.
Seasonal and interannual variation of streamflow pathways and biogeochemical implications in semi‐arid, forested catchments in Valles Caldera, New Mexico
Authors: Liu Fengjing , Parmenter Robert , Brooks Paul D. , Conklin Martha H. , Bales Roger C.
Published: October 2008

Pathways of streamflow were investigated using geochemical tracers in ungauged headwater and higher‐order streams in the semi‐arid, forested, Valles Caldera, New Mexico. Combining diagnostic tools of mixing models and endmember mixing analysis (EMMA) shows that streamflow at East Fork Jemez River and San Antonio West (both > 120 km2) was controlled by mixing of three endmembers: near‐surface runoff, subsurface flow and groundwater. The contribution of near‐surface runoff was primarily controlled by soil moisture and evapotranspiration, and was much higher in wet years (2005 and 2007) than a dry year (2006) and during the spring snowmelt than in the summer monsoon. Streamflow at the San Antonio Toledo headwater catchment (55 km2) was dominated by subsurface flow alone, consistent with the distribution of coarse‐textured, well‐drained soils at higher elevations. During the snowmelt period and at catchments with higher near‐surface runoff contributions, nutrient concentrations in streams were found to be higher, as a result of nutrient leaching from the upper organic‐rich soil horizons by near‐surface runoff. These results highlight the importance of seasonal and interannual variability of hydrology in semi‐arid regions, and the role of flowpaths in controlling sources of nutrients in streams. Copyright © 2008 John Wiley & Sons, Ltd.
Evaluation of distributed soil moisture simulations through field observations during the North American monsoon in Redondo Creek, New Mexico
Authors: Mahmood Taufique H. , Vivoni Enrique R.
Published: October 2008

Soil moisture is a key ecohydrological variable connecting ecosystem functions with hydrological processes in forested mountain basins. Nevertheless, few studies have investigated the spatiotemporal variations of soil moisture in mountainous settings or attempted to understand these through a modelling framework. In this study, we evaluate distributed soil moisture simulations in the Redondo Creek, New Mexico, using a set of field observations consisting of hourly data at a weather station and daily samples of soil moisture obtained during an intensive field campaign. Results indicate that simulated soil moisture patterns during the North American monsoon (NAM) are in reasonable agreement with observations across a range of ecosystems (wetland, grassland and forest). Using a set of temporal and spatial statistics, we quantify the distributed model performance at the point, ecosystem and basin scales. We find improved performance at the grassland and forest sites as compared to the near‐stream wetlands. As a strong test of the model, we also compare the observed and simulated soil moisture probability density functions across the different ecosystems, finding that the overall match for grassland and forest was superior to the wetland areas. On the basis of the model simulations, we quantify, through visual inspection and geostatistical analysis, the controlling factors (rainfall, topography, vegetation and soils) on the soil moisture spatial patterns at different stages during the summer monsoon. Confidence in the distributed model gained through this analysis can open avenues for process studies and basin‐scale predictions of mountain ecohydrology. Copyright © 2008 John Wiley & Sons, Ltd.
Comparison of soil moisture and meteorological controls on pine and spruce transpiration
Authors: Small Eric E. , McConnell Joseph R.
Published: October 2008

Transpiration is an important component of the water balance in the high elevation headwaters of semi‐arid drainage basins. We compare the importance of soil moisture and meteorological controls on transpiration and quantify how these controls are different at a ponderosa pine site and a spruce site in the Jemez river drainage basin of northern New Mexico, a sub‐basin of the Rio Grande. If only soil moisture controls fluctuations in transpiration, then simple hydrologic models focussed only on soil moisture limitations are reasonable for water balance studies. If meteorological controls are also critical, then more complex models are required.

We measured volumetric water content in the soil and sap velocity, and assumed that transpiration is proportional to sap velocity. Ponderosa sap velocity varies with root zone soil moisture. Nearly all of the scatter in the ponderosa sap velocity–soil moisture relationship can be predicted using a simple model of potential evapotranspiration (ET), which depends only on measured incident radiation and air temperature. Therefore, simple hydrologic models of ponderosa pine transpiration are warranted. In contrast, spruce sap velocity does not clearly covary with soil moisture. Including variations in potential evapotranspiration does not clarify the relationship between sap velocity and soil moisture. Likewise, variations in radiation, air temperature, and vapour pressure do not explain the observed fluctuations in sap velocity, at least according to the standard models and parameters for meteorological restrictions on transpiration. Both the simple and more complex models commonly used to predict transpiration are not adequate to model the water balance in the spruce forest studied here. Copyright © 2008 John Wiley & Sons, Ltd.
A Convenient Mode to Stabilize MI Metal Ions by Using Thiosemicarbazones
Authors: Castiñeiras Alfonso , Pedrido Rosa , Pérez‐Alonso Gael
Published: October 2008

We investigated the coordinative behaviour of the phosphanylthiosemicarbazone ligand 2‐[2‐(diphenylphosphanyl)benzylidene]‐N‐phenylthiosemicarbazone (HLPPh) towards coinage MI metal ions (M = Cu, Ag, Au). The complexes obtained, with formulae [Cu(HLPPh)2]Br (1), [Cu(HLPPh)2]I·H2O (2), [Ag(HLPPh)(NO3)]·3H2O (3) and [Au2(HLPPh)2]·3CH3OH (4), were satisfactorily characterized by elemental analysis, IR and 1H/31P NMR spectroscopy as well as ESI mass spectrometry. In addition, we obtained the crystal structure of the complex [Au2(μ‐S,P‐HLPPh)2]Cl2 (5), which is the first example of a homoleptic thiosemicarbazone AuI complex, because the AuI ion has been stabilized by exclusively using a phosphanylthiosemicarbazone ligand. We also performed preliminary luminescence studies for these complexes, as well as the screening of its biological activity against human cervical carcinoma (HeLa) cells. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Asymmetric Malonic and Acetoacetic Acid Syntheses – A Century of Enantioselective Decarboxylative Protonations
Authors: Blanchet Jérôme , Baudoux Jérôme , Amere Mukkanti , Lasne Marie‐Claire , Rouden Jacques
Published: October 2008

The enantioselective decarboxylative protonation (EDP) of malonic or acetoacetic acid derivatives is a synthetic methodology by which the chirality of the product is generated during the enol/enolate protonation step. Although EDP is a century‐old reaction, it has not received much attention until recently. This review focuses on the EDP as an alternative to the strong‐base‐mediated deprotonation/asymmetric reprotonation for the stereocontrol of C–H bond formation. The diverse synthetic approaches are classified according to the type of catalysis used, which are organic, metallic or enzymatic.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Kinetic Resolution of β‐Alkenyl‐, β‐Alkynyl‐ and β‐Flavenyl‐Substituted β‐Hydroxy Esters in Asymmetric Dehydration
Authors: Lee Min Hee , Choi Eui Ta , Kim Dajung , Lee Yoon Min , Park Yong Sun
Published: October 2008

Catalytic asymmetric dehydration of β‐alkenyl‐ or alkynyl‐substituted β‐hydroxy esters by kinetic resolution has been investigated with five different chiral ligands 3–7. The kinetic resolution of a variety of racemic β‐hydroxy tert‐butyl esters in the presence of a prolinol chiral ligand and BrZnCH2CO2tBu provided highly enantio‐enriched β‐hydroxy esters 9–22 with selectivity factors ranging from 11 to 59. In addition, the application of this asymmetric synthetic methodology to the preparation of enantio‐enriched flavene derivatives 23–29 is demonstrated. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Dynamic two state stochastic models for ecological regime shifts
Authors: Møller Jan Kloppenborg , Carstensen Jacob , Madsen Henrik , Andersen Tom
Published: October 2008

A simple non‐linear stochastic two state, discrete‐time model is presented. The interaction between benthic and pelagic vegetation in aquatic ecosystems subject to changing external nutrient loading is described by the non‐linear functions. The dynamical behavior of the deterministic part of the model illustrates that hysteresis effect and regime shifts can be obtained for a limited range of parameter values only. The effect of multiplicative noise components entering at different levels of the model is presented and discussed. Including noise leads to very different results on the stability of regimes, depending on how the noise propagates through the system. The dynamical properties of a system should therefore be described through propagation of the state distributions rather than the state means and consequently, stochastic models should be compared in a probabilistic framework. Copyright © 2008 John Wiley & Sons, Ltd.
An in‐home geriatric programme for vulnerable community‐dwelling older people improves the detection of dementia in primary care
Authors: Perry M. , Melis R. J. F. , Teerenstra S. , Drašković I. , van Achterberg T. , van Eijken M. I. J. , Lucassen P. , Rikkert M. G. M. Olde
Published: October 2008

Background/objective

Dementia is under‐diagnosed in primary care. This study investigated whether an in‐home geriatric assessment and management programme could improve the identification of patients with dementia in primary care.

Methods

A secondary analysis was performed, using data of a randomised controlled trial that studied the effects of an in‐home geriatric evaluation and management programme compared with usual care. In this trial, 151 vulnerable community‐dwelling patients, aged 70 years and older, participated: 86 in the intervention group and 66 in de control group. The effect of the programme on the dementia detection rate was determined by comparing the number of new dementia diagnoses in both study arms at 6 months follow‐up.

Results

Of all 151 participants, 38 (25%) had a registered dementia diagnosis at baseline. During follow‐up, 23 of 113 patients without a registered dementia diagnosis at baseline were identified as suffering from dementia. The difference between the numbers of new dementia diagnoses in the intervention group (19 of 66 patients) and the control group (4 of 47 patients) was significant. (p = 0.02)

Conclusion

An in‐home geriatric assessment and management programme for vulnerable older patients improves the detection of dementia and can therefore contribute to overcoming of under‐diagnosis of dementia. Copyright © 2008 John Wiley & Sons, Ltd.
Angiosarcoma developing after curative induction chemotherapy and radiotherapy for locally advanced squamous cell carcinoma of the larynx
Authors: Gagnon Patrick J. , Galderisi Chad , Page Brandi R. , Holland John M.
Published: October 2008

Background

Angiosarcoma arising after radiation is described in breast cancer but occurs elsewhere. Here, we present an angiosarcoma of the neck occurring after curative chemoradiation.

Methods

This is a case of angiosarcoma developing 5 years after curative therapy for T3N0 squamous cell carcinoma of the supraglottic larynx. Therapy consisted of 3 cycles of induction cisplatin/5‐fluorouracil chemotherapy followed by radiotherapy. The patient did well until developing a rapidly progressive lesion of the left neck. Examination showed a 7‐cm mass and biopsy revealed angiosarcoma. CT scans assessed the local extent of the tumor and ruled out metastatic disease prior to initiating therapy.

Results

Therapy consisted of 4 cycles of paclitaxel chemotherapy. At completion, examination revealed mild induration of the neck with near‐complete resolution of the mass. Imaging confirmed this excellent response.

Conclusion

This rare therapy‐related second malignancy developed after curative larynx‐preserving treatment. Paclitaxel was an effective therapy in this setting. © 2008 Wiley Periodicals, Inc. Head Neck, 2009
Mandibular osteotomies for access to select parapharyngeal space neoplasms
Authors: Kolokythas Antonia , Eisele David W. , El‐Sayed Ivan , Schmidt Brian L.
Published: October 2008

Background

Tumors involving the parapharyngeal space present a challenge of surgical access.

Methods

We reviewed all parapharyngeal space tumors resected at the University of California, San Francisco, between 2003 and 2006 and identified 14 patients who had a mandibular osteotomy to enhance surgical access to the parapharyngeal space.

Results

The surgical approach for the 14 patients who had a mandibulotomy was accomplished via either 1 or 2 mandibular osteotomies. A single paramedian osteotomy between the canine and the first premolar was used in 4 cases, whereas a combination of a horizontal osteotomy above the lingula and a paramedian osteotomy between the canine and first premolar was employed in 8 cases. A lingual dental splint and rigid fixation were used to achieve mandibular stabilization and fixation.

Conclusion

We found that the single and double mandibular osteotomies provided excellent surgical access allowing for total tumor removal with few sequelae. © 2008 Wiley Periodicals, Inc. Head Neck, 2009
In vivo investigation of CD133 as a putative marker of cancer stem cells in Hep‐2 cell line
Authors: Wei Xu Dong , Zhou Liang , Cheng Lei , Tian Jie , Jiang Jack J. , MacCallum Julia
Published: October 2008

Background

Mounting evidence suggests that most tumors consist of a heterogeneous population of cells with a subset population that has the exclusive tumorigenic ability. They are called cancer stem cells (CSCs). CSCs can self‐renew to generate additional CSCs and also differentiate to generate phenotypically diverse cancer cells with limited proliferative potential. They have been identified in a variety of tumors. In this study, we identify the marker of CSCs in the established human laryngeal tumor Hep‐2 cell line in vivo. Our in vitro experiment shown as CD133, a 5‐transmembrane glycoprotein expressed in Hep‐2 cell line. CD133 was supposed as a candidate of CSC in laryngeal carcinoma. In this study, the expression of CD133 was detected in a Hep‐2 cell line. Applying the magnetic cell sorting (MACS) technology, we reported the results of purifying CD133 positive cells from a Hep‐2 cell line. Three‐type cells' tumor‐forming ability was examined in vivo to identify the marker of CSCs in Hep‐2 cell line.

Methods

CD133 was selected as a putative marker of CSC in laryngeal carcinoma, Hep‐2 cell lines. Flow cytometry was used to detect the expression of CD133 in the Hep‐2 cell line. Immunomagnetic beads were applied to purify CD133‐positive cells. CD133(+), CD133(−) tumor cells, and unsorted Hep‐2 cells were injected into severe combined immune deficiency (SCID) mice individually to observe tumor‐forming ability.

Results

Only a small proportion (3.15% ± 0.83%) of cells in the Hep‐2 cell line express the CD133 marker. In comparison with CD133(−) tumor cells and unsorted cells, CD133(+) cells possess a marked capacity for tumor formation in vivo (p <.05).

Conclusion

CD133 is 1 of the markers for CSCs in human laryngeal tumors of the Hep‐2 cell line. Work on the characterization of these cells provides a powerful tool to investigate the tumorigenic process in the larynx and to develop therapies targeting the CSC. © 2008 Wiley Periodicals, Inc. Head Neck, 2009
Incidence and risk factors of bisphosphonate‐associated osteonecrosis of the jaws
Authors: Stumpe Matthew R. , Chandra Rakesh K. , Yunus Furhan , Samant Sandeep
Published: October 2008

Background

Intravenous bisphosphonate therapy has been used for treatment of benign and malignant bone diseases and has been linked to osteonecrosis of the jaws.

Methods

Records of 638 patients treated with intravenous bisphosphonates were reviewed. Drug used, number of infusions, dosing interval, dosage, duration, and occasion of osteonecrosis, diagnosed by history and physical examination, were analyzed.

Results

The overall incidence of osteonecrosis was 0.94% (6/638). No significant relationship was observed between the incidence of osteonecrosis and demographic parameters, primary tumor, cumulative drug dose, or dosing interval. However, patients who developed osteonecrosis had a significantly greater mean number of infusions (p = .016) and significantly greater mean hours of infusion time (p = .0036).

Conclusions

The findings suggest positive correlation between the development of osteonecrosis and drug exposure as measured by number of infusions and total infusion hours. However, the relatively low incidence of osteonecrosis precluded definition of a direct dose–response relationship. © 2008 Wiley Periodicals, Inc. Head Neck, 2009
Prospective study of early detection of pharyngeal superficial carcinoma with the narrowband imaging laryngoscope
Authors: Ugumori Toru , Muto Manabu , Hayashi Ryuichi , Hayashi Tomomasa , Kishimoto Seiji
Published: October 2008

Background

The newly developed narrowband imaging (NBI) gastrointestinal endoscope makes possible the detection of superficial carcinoma in the oropharynx and hypopharynx, which is difficult with the conventional laryngoscope. Here, we investigated whether the combined use of laryngoscope with NBI allows the detection of superficial carcinoma in this region.

Methods

A total of 51 superficial, histologically confirmed lesions in 29 patients were studied. The quality of visualization of superficial carcinoma in the oropharynx and hypopharynx using the NBI‐equipped laryngoscope was evaluated in comparison with the results by conventional laryngoscopy.

Results

The NBI laryngoscope provided better detection of the irregular microvascular pattern of carcinoma than the conventional laryngoscope (p <.05) and better visualization of the demarcation line (p <.05), and thus significantly better visualization of the lesions.

Conclusion

The NBI laryngoscope may play an important role in the diagnosis and treatment of superficial carcinoma in the oropharynx and hypopharynx. © 2008 Wiley Periodicals, Inc. Head Neck, 2009
In vitro–targeted gene identification in patients with hepatitis C using a genome-wide microarray technology #
Authors: Hagist Susanne , Sültmann Holger , Millonig Gunda , Hebling Ulrike , Kieslich Dörthe , Kuner Rupert , Balaguer Sabrina , Seitz Helmut-Karl , Poustka Annemarie , Mueller Sebastian
Published: October 2008

Iron in association with reactive oxygen species (ROS) is highly toxic, aggravating oxidative stress reactions. Increased iron not only plays an important role in the progression of hereditary hemochromatosis (HH) but also in common liver diseases such as chronic hepatitis C. The underlying mechanisms of hepatitis C virus (HCV)-mediated iron accumulation, however, are poorly understood. We introduce an in vitro–targeted approach to identify ROS/iron-regulated genes in patients with HCV using a genome-wide DNA microarray. The sensitivity of the 32,231 complementary DNA clone-carrying microarray was approximately 20% as estimated by detecting target genes of the genome-wide transcription factor hypoxia inducible factor 1α. Upon in vitro challenge to iron and oxidative stress, 265 iron-related and 1326 ROS-related genes could be identified in HepG2 cells; 233 significantly regulated genes were found in patients with mild (HCV) or severe (HH) iron deposition. Notably, 17 of the in vitro–selected genes corresponded to the genes identified in patients with HCV or HH. Among them, natriuretic peptide precursor B (NPPB) was the only iron-regulated gene identified in vitro that was differentially regulated between HCV and HH. Reverse-transcription polymerase chain reaction confirmed most of the microarray-identified genes in an even larger group of patients (n = 12). In patients with HCV, these included genes that are associated with RNA processing (MED9/NFAT, NSUN2), proliferation, differentiation, hypoxia, or iron metabolism (ISG20, MIG6, HIG2, CA9, NDRG1), whereas none of the nine known iron-related genes showed significant differences between HCV and HH. Conclusion: Although high-density microarray technology is less suitable for routine liver diagnosis, its use in combination with prior in vitro selection is a powerful approach to identify candidate genes relevant for liver disease. (Hepatology 2009;49:378–386.)
Missense mutations and single nucleotide polymorphisms in ABCB11 impair bile salt export pump processing and function or disrupt pre-messenger RNA splicing #
Authors: Byrne Jane A. , Strautnieks Sandra S. , Ihrke Gudrun , Pagani Franco , Knisely A. S. , Linton Kenneth J. , Mieli-Vergani Giorgina , Thompson Richard J.
Published: October 2008

The gene encoding the human bile salt export pump (BSEP), ABCB11, is mutated in several forms of intrahepatic cholestasis. Here we classified the majority (63) of known ABCB11 missense mutations and 21 single-nucleotide polymorphisms (SNPs) to determine whether they caused abnormal ABCB11 pre-messenger RNA splicing, abnormal processing of BSEP protein, or alterations in BSEP protein function. Using an in vitro minigene system to analyze splicing events, we found reduced wild-type splicing for 20 mutations/SNPs, with normal mRNA levels reduced to 5% or less in eight cases. The common ABCB11 missense mutation encoding D482G enhanced aberrant splicing, whereas the common SNP A1028A promoted exon skipping. Addition of exogenous splicing factors modulated several splicing defects. Of the mutants expressed in vitro in CHO-K1 cells, most appeared to be retained in the endoplasmic reticulum and degraded. A minority had BSEP levels similar to wild-type. The SNP variant A444 had reduced levels of protein compared with V444. Treatment with glycerol and incubation at reduced temperature overcame processing defects for several mutants, including E297G. Taurocholate transport by two assessed mutants, N490D and A570T, was reduced compared with wild-type. Conclusion: This work is a comprehensive analysis of 80% of ABCB11 missense mutations and single-nucleotide polymorphisms at pre-mRNA splicing and protein processing/functional levels. We show that aberrant pre-mRNA splicing occurs in a considerable number of cases, leading to reduced levels of normal mRNA. Thus, primary defects at either the protein or the mRNA level (or both) contribute significantly to BSEP deficiency. These results will help to develop mutation-specific therapies for children and adults suffering from intrahepatic cholestasis due to BSEP deficiency. (Hepatology 2008.)
The novel CD4+CD25+ regulatory T cell effector molecule fibrinogen-like protein 2 contributes to the outcome of murine fulminant viral hepatitis #
Authors: Shalev Itay , Wong Kit Man , Foerster Katharina , Zhu Yi , Chan Cecilia , Maknojia Asif , Zhang Jianhua , Ma Xue-Zhong , Yang Xiao Chun , Gao Julia Fang , Liu Hao , Selzner Nazia , Clark David A. , Adeyi Oyedele , Phillips James M. , Gorczynski Reginald R. , Grant David , McGilvray Ian , Levy Gary
Published: October 2008

Fulminant viral hepatitis (FH) remains an important clinical problem in which the underlying pathogenesis is not well understood. Here, we present insight into the immunological mechanisms involved in FH caused by murine hepatitis virus strain 3 (MHV-3), indicating a critical role for CD4+CD25+ regulatory T cells (Tregs) and production of the novel Treg effector molecule FGL2. Before infection with MHV-3, susceptible BALB/cJ mice had increased numbers of Tregs and expression of fgl2 messenger RNA (mRNA) and FGL2 protein compared with resistant A/J mice. After MHV-3 infection, plasma levels of FGL2 in BALB/cJ mice were significantly increased, correlating with increased percentage of Tregs. Treatment with anti-FGL2 antibody completely inhibited Treg activity and protected susceptible BALB/cJ mice against MHV-3-liver injury and mortality. Adoptive transfer of wild-type Tregs into resistant fgl2
−/− mice increased their mortality caused by MHV-3 infection, whereas transfer of peritoneal exudate macrophages had no adverse effect. Conclusion: This study demonstrates that FGL2 is an important effector cytokine of Tregs that contributes to susceptibility to MHV-3–induced FH. The results further suggest that targeting FGL2 may lead to the development of novel treatment approaches for acute viral hepatitis infection. (Hepatology 2009.)
14‐3‐3β‐Rac1‐p21 activated kinase signaling regulates Akt1‐mediated cytoskeletal organization, lamellipodia formation and fibronectin matrix assembly
Authors: Somanath Payaningal R. , Byzova Tatiana V.
Published: October 2008

Akt1 belongs to the three‐gene Akt family and functions as a serine–threonine kinase regulating phosphorylation of an array of substrates and mediating cellular processes such as cell migration, proliferation, survival, and cell cycle. Our previous studies have established the importance of Akt1 in angiogenesis and absence of Akt1 resulted in impaired integrin activation, adhesion, migration, and extracellular matrix assembly by endothelial cells and fibroblasts. In this study, we identify the downstream signaling pathways activated by Akt1 in the regulation of these cellular events. We demonstrate here that Akt1 is necessary for the growth factor stimulated activation of 14‐3‐3β‐Rac1‐p21 activated kinase (Pak) pathway in endothelial cells and fibroblasts. While activation of Akt1 resulted in translocation of Rac1 to membrane ruffles, enhanced Rac1 activity, Pak1 phosphorylation, and lamellipodia formation, resulting in enhanced adhesion and assembly of fibronectin, inhibition of Akt1 resulted in inhibition of these processes due to impaired Rac1‐Pak signaling. Formation of lamellipodia, adhesion, and fibronectin assembly by myristoylated Akt1 expression in NIH 3T3 fibroblasts was inhibited by co‐expression with either dominant negative Rac1 or dominant negative Pak1. In contrast, impaired lamellipodia formation, adhesion, and fibronectin assembly by dominant negative‐Akt1 expression was rescued by co‐expression with either constitutively active‐Rac1 or ‐Pak1. Moreover, previously reported defects in adhesion and extracellular matrix assembly by Akt1−/− fibroblasts could be rescued by expression with either active‐Rac1 or ‐Pak1, implying the importance of Rac1‐Pak signaling in growth factor stimulated cytoskeletal assembly, lamellipodia formation and cell migration in endothelial cells and fibroblasts downstream of Akt1 activation. J. Cell. Physiol. 218: 394–404, 2009. © 2008 Wiley‐Liss, Inc.
Preparation of sodium carboxymethyl cellulose from paper sludge
Authors: He Xiaojia , Wu Shaozu , Fu Dongkang , Ni Jinren
Published: October 2008

BACKGROUND: This paper describes the reuse of paper sludge, an industrial solid waste, for the preparation of sodium carboxymethyl cellulose (CMC). The process includes pretreatment, basification and etherification.

RESULTS: The optimal pretreatment condition involved the addition of 6.7% hydrochloric acid to the paper sludge for 30 min at 70 °C. The order of factors influencing the effect of reaction was: etherification temperature > sodium hydroxide dose > basification temperature > etherification time > sodium chloroacetate dose. The optimal preparation condition of CMC was: mpapersludge: msodiumhydroxide: msodiumchloroacetate = 0.9:0.8:1.15; basification at 40 °C; etherification at 60 °C for 1 h. Under these conditions, certified CMC with viscosity less than 20 mPa· s, DS more than 0.50 and purity more than 90% was produced. The results of Fourier transform infrared (FTIR) and X‐ray diffraction (XRD) spectra analyses indicated that the product has characteristics of high degree of substitution (DS) and low crystallinity. The coated paper using CMC prepared from paper sludge as a water retention agent can meet the quality standards of GB/T 10335.1‐2005.

CONCLUSION: Preparation of CMC from paper sludge can be considered a feasible alternative, generating value‐added product and contributing to solving environmental problems resulting from paper sludge. Copyright © 2008 Society of Chemical Industry