bluuebunny/crossref_metadata_2025 huggingface dataset:
A role for the default mode network in the bases of disorders of consciousness
Authors: Fernández‐Espejo Davinia , Soddu Andrea , Cruse Damian , Palacios Eva M. , Junque Carme , Vanhaudenhuyse Audrey , Rivas Eva , Newcombe Virginia , Menon David K. , Pickard John D. , Laureys Steven , Owen Adrian M.
Published: April 2012

Objective:

Functional connectivity in the default mode network (DMN) is known to be reduced in patients with disorders of consciousness, to a different extent depending on their clinical severity. Nevertheless, the integrity of the structural architecture supporting this network and its relation with the exhibited functional disconnections are very poorly understood. We investigated the structural connectivity and white matter integrity of the DMN in patients with disorders of consciousness of varying clinical severity.

Methods:

Fifty‐two patients—19 in a vegetative state (VS), 27 in a minimally conscious state (MCS), and 6 emerging from a minimally conscious state (EMCS)—and 23 healthy volunteers participated in the study. Structural connectivity was assessed by means of probabilistic tractography, and the integrity of the resulting fibers was characterized by their mean fractional anisotropy values.

Results:

Patients showed significant impairments in all of the pathways connecting cortical regions within this network, as well as the pathway connecting the posterior cingulate cortex/precuneus with the thalamus, relative to the healthy volunteers. Moreover, the structural integrity of this pathway, as well as that of those connecting the posterior areas of the network, was correlated with the patients' behavioral signs for awareness, being higher in EMCS patients than those in the upper and lower ranges of the MCS patients, and lowest in VS patients.

Interpretation:

These results provide a possible neural substrate for the functional disconnection previously described in these patients, and reinforce the importance of the DMN in the genesis of awareness and the neural bases of its disorders. Ann Neurol 2012;72:335–343.
Structure regulation of silk fibroin films for controlled drug release
Authors: Wei Qiao‐Na , Huang Ai‐Min , Ma Lin , Huang Zilun , Huang Xi , Qiang Pan‐Pan , Gong Zhu‐Ping , Zhang Li
Published: April 2012

Silk fibroin (SF) films were prepared using a casting method and the change of secondary structure and crystal structure owing to treatment with ethanol–water mixtures of different concentrations was investigated by Fourier transform infrared spectroscopy and X‐ray diffraction. The results were used to reveal the influence of structure of SF matrix on the release kinetics of drug compounds incorporated. It was found that the content of silk II structure, constituted by β‐sheet, first increased and then decreased with increasing ethanol concentration ranging from 50 to 90%, reaching a maximum around 70–80%. The release kinetics of Rhodamine B, a model compound for small molecule drugs, was described by Peppas equation. The results indicated that Rhodamine B released from SF films via Fickian diffusion mechanism and the diffusional exponent n increased with increasing β‐sheet content in the matrix. The experimental data had a good linear fit, suggesting that the silk II crystal could be used as a natural regulator for drug release from SF material. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Investigation on flame retardancy and thermal degradation of flame retardant poly(butylene succinate)/bamboo fiber biocomposites
Authors: Nie Shibin , Liu Xueli , Dai Guanglong , Yuan Shujie , Cai Feng , Li Benxia , Hu Yuan
Published: April 2012

Poly(butylene succinate)/bamboo fiber (BBF) biocomposites were prepared by melt blending method. Microencapsulated ammonium polyphosphate (MCAPP) was used as flame retardants to prepare flame retardant BBF biocomposites. The thermal degradation and flame retardant properties of BBF biocomposites were investigated. The volatilized products of the thermal degradation of flame retardant BBF biocomposite are saturated hydrocarbons, unsaturated alkane, CO2, carboxylic acid, acid anhydride, aromatic compounds, NH3, and CH3OH. The peak of heat release rate (pHRR) and total heat release (THR) of flame retardant BF biocomposites decrease substantially compared with that without MCAPP. The pHRR value of flame retardant BBF biocomposites decreases from 443.2 to 236.2 kW m−2 and the THR value decreases from 62.0 to 36.1 kW m−2. Furthermore, MCAPP shows the best flame retardant property at the same loading, compared with other flame retardants such as Mg(OH)2, and Al(OH)3. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Adipic acid interaction enhances the mechanical and thermal stability of natural polymers
Authors: Mitra Tapas , Sailakshmi G. , Gnanamani A. , Mandal A. B.
Published: April 2012

Application of biopolymers for biomedical applications limits with the functional and structural properties of the materials. Crosslinkers are used to provide the requisite properties. The question on biocompatibility of the existing crosslinkers necessitates the need for alternative crosslinkers. In the present study, adipic acid was chosen as crosslinker and evaluated the mode of interaction with chitosan and type‐I collagen. A 3D scaffold biopolymer material was prepared using chitosan at 1.0% (w/v) and adipic acid at 0.2% (w/v), similarly collagen 0.5% (w/v) and adipic acid 0.2% (w/v) displayed an improved mechanical strength and in addition found biocompatible for NIH 3T3 fibroblast cells. The chemistry behind the interaction and the characteristics of the biopolymer material obtained upon crosslinking suggests that noncovalent interactions play the major role in deciding the property of the said materials and their suitability for biomedical applications. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Homocysteine Exposure Affects Early Hemodynamic Parameters of Embryonic Chicken Heart Function
Authors: Oosterbaan Annelien M. , Bon Els , Steegers‐Theunissen Regine P.M. , Van Der Steen Anton F.W. , Ursem Nicolette T.C.
Published: April 2012

Maternal hyperhomocysteinemia has been associated with an increased risk of newborns with a congenital heart defect. This has been substantiated in the chicken embryo, as congenital heart defects have been induced after homocysteine treatment. Comparable heart defects are observed in venous clipping studies, a model of altered embryonic blood flow. Because of this overlap in heart defects, our aim was to test the hypothesis that homocysteine would cause alterations in embryonic heart function that precede the structural malformations previously described. Therefore, Doppler flow velocity waveforms were recorded in both primitive ventricles and the outflow tract of the embryonic heart of homocysteine treated and control chicken embryos at embryonic day 3.5. Homocysteine treatment consisted of 50 μL 0.05 M L‐homocysteine thiolactone at 24, 48, and 72 hr. Homocysteine‐treated embryos displayed significantly lower mean heart rates of 134 (SD 22) bpm, compared to 150 (14) bpm in control embryos. Homocysteine treatment caused an inhibiting effect on hemodynamic parameters, and altered heart function was presented by a shift in the proportions of the different wave times in percentage of total cycle time. Homocysteine induces changes in hemodynamic parameters of early embryonic chicken heart function. These changes may precede morphological changes and contribute to the development of CHD defects through alterations in shear stress and shear stress related genes, as seen before in venous clipping studies. Anat Rec,, 2012. © 2012 Wiley Periodicals, Inc.
Map of nonprofit organization websites in Israel
Authors: Bar‐Ilan Judit , Azoulay Rina
Published: April 2012

In this study, we consider the structure and linking strategy of Hebrew websites of several nonprofit organizations. Because nonprofit organizations differ from commercial, educational, or governmental sectors, it is important to understand the ways they utilize the web. To the best of our knowledge, the linking structure of nonprofit organizations has not been previously studied.

We surveyed websites of 54 nonprofit organizations in Israel; most of these sites have at least 100 volunteers. We compared their orientation and contents and we built their linking map. We divided the organizations into four main groups: economic aid and citizen rights organizations, health aid organizations, organizations supporting families and individuals with special needs, and organizations for women and children. We found that the number of links inside the special needs group is much higher than in the other groups. We tried to explain this behavior by considering the data obtained from the site‐linking graph. The value of our results is in defining and testing a method to investigate a group of nonprofit organizations, using a case study of Israeli organizations.
Exposure classification of MRI workers in epidemiological studies
Authors: Hansson Mild Kjell , Hand Jeff , Hietanen Maila , Gowland Penny , Karpowicz Jolanta , Keevil Stephen , Lagroye Isabelle , van Rongen Eric , Scarfi Maria Rosaria , Wilén Jonna
Published: April 2012

We estimate that there are about 100,000 workers from different disciplines, such as radiographers, nurses, anesthetists, technicians, engineers, etc., who can be exposed to substantial electromagnetic fields (compared to normal background levels) around magnetic resonance imaging (MRI) scanners. There is a need for well‐designed epidemiological studies of MRI workers but since the exposure from MRI equipment is a very complex mixture of static magnetic fields, switched gradient magnetic fields, and radiofrequency electromagnetic fields (RF EMF), it is necessary to discuss how to assess the exposure in epidemiological studies. As an alternative to the use of job title as a proxy of exposure, we propose an exposure categorization for the different professions working with MRI equipment. Specifically, we propose defining exposure in three categories, depending on whether people are exposed to only the static field, to the static plus switched gradient fields or to the static plus switched gradient plus RF fields, as a basis for exposure assessment in epidemiological studies. Bioelectromagnetics 34:81–84, 2013. © 2012 Wiley Periodicals, Inc.
Hierarchical Bayesian modeling of heterogeneous cluster‐ and subject‐level associations between continuous and binary outcomes in dairy production
Authors: Bello Nora M. , Steibel Juan P. , Tempelman Robert J.
Published: April 2012

The augmentation of categorical outcomes with underlying Gaussian variables in bivariate generalized mixed effects models has facilitated the joint modeling of continuous and binary response variables. These models typically assume that random effects and residual effects (co)variances are homogeneous across all clusters and subjects, respectively. Motivated by conflicting evidence about the association between performance outcomes in dairy production systems, we consider the situation where these (co)variance parameters may themselves be functions of systematic and/or random effects. We present a hierarchical Bayesian extension of bivariate generalized linear models whereby functions of the (co)variance matrices are specified as linear combinations of fixed and random effects following a square‐root‐free Cholesky reparameterization that ensures necessary positive semidefinite constraints. We test the proposed model by simulation and apply it to the analysis of a dairy cattle data set in which the random herd‐level and residual cow‐level effects (co)variances between a continuous production trait and binary reproduction trait are modeled as functions of fixed management effects and random cluster effects.
Classification of and cytoreductive surgery for low-grade appendiceal mucinous neoplasms
Authors: McDonald J R , O'Dwyer S T , Rout S , Chakrabarty B , Sikand K , Fulford P E , Wilson M S , Renehan A G
Published: April 2012

Background

Low-grade appendiceal mucinous neoplasm (LAMN) is a precursor lesion for pseudomyxoma peritonei (PMP), which, if treated suboptimally, may later disseminate throughout the abdominal cavity. The role of cytoreductive surgery for these relatively early lesions is unclear.

Methods

Clinicopathological details and treatment outcomes of patients with a LAMN and disease limited to the appendix or immediate periappendiceal tissues, referred to a national treatment centre between 2002 and 2009, were evaluated prospectively.

Results

Of 379 patients with a diagnosis of PMP, 43 (median age 49 years) had LAMNs localized to the appendix and periappendiceal tissue. Thirty-two patients initially presented with symptoms of acute appendicitis or right iliac fossa pain. Two distinct lesions were identified: type I (disease confined to the appendiceal lumen) and type II (mucin and/or neoplastic epithelium in the appendiceal submucosa, wall and/or periappendiceal tissue, with or without perforation). Type I lesions were managed by a watch-and-wait surveillance policy with serial measurement of tumour markers and computed tomography in 14 of 16 patients. Seventeen of 27 patients with type II lesions underwent risk-reducing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy with low morbidity. After a median follow-up of 40 months, there was no disease progression in either treatment pathway.

Conclusion

This study identified two LAMN subtypes. Type II lesions have pathological features of increased risk for dissemination and should be considered for risk-reducing cytoreductive surgery.
Identification of the metabolites after oral administration of extract of ziziphi spinosae semen to rats or dogs by high‐performance liquid chromatography/linear ion trap FTICR hybrid mass spectrometry
Authors: Ren Yan , Wang Pengyuan , Wu Caisheng , Zhang Jinlan , Niu Chunyan
Published: April 2012

Ziziphi spinosae semen (ZSS) is a traditional Chinese medicine that has been widely used to treat insomnia and anxiety. Modern pharmacological studies have demonstrated that flavonoids are the main active compounds in ZSS. However, the metabolites and the metabolic pathways of flavonoids in ZSS have not been investigated thoroughly. In this study, a method based on high‐performance liquid chromatography coupled with Fourier transform ion cyclotron resonance mass spectrometry (HPLC/FTICR‐MS) was established to identify the metabolites of flavonoids after oral administration of extract of ZSS to rats or dogs, using parent mass list‐triggered data‐dependent multiple‐stage mass analysis at a resolving power of 50,000 in the external calibration mode. The mass accuracies obtained for all full‐scan analyses were less than 4 ppm (<2 ppm in most cases). A total of 15 compounds were detected in biological samples of rats and dogs, and nine compounds were identified. The metabolic pathways of flavonoids of ZSS in rats and dogs were proposed. The results may help better understand the material basis and pharmacological mechanism of ZSS. Copyright © 2012 John Wiley & Sons, Ltd.
Development and validation of a sensitive LC/MS/MS method for the determination of γ‐tocotrienol in rat plasma: application to pharmacokinetic studies
Authors: Liang Su , Bian Xiaomei , Ma Jing , Arogunjo Motolani , Deorukhkar Amit A. , Krishnan Sunil , Xie Huan
Published: April 2012

γ‐Tocotrienol has attracted much attention owing to its multiple health benefits. This study developed and validated a simple, specific, sensitive and reliable LC/MS/MS method to analyze γ‐tocotrienol in rat plasma. Plasma samples (50 μL) were extracted with internal standard solution (25 ng/mL of itraconazole) in acetonitrile (200 μL) with an average recovery of 44.7% and an average matrix effect of −2.9%. The separation of γ‐tocotrienol and internal standard from the plasma components was achieved with a Waters XTerra® MS C18 column with acetonitrile–water as mobile phase. Analysis was performed under positive ionization electrospray mass spectrometer via the multiple reaction monitoring. The standard curve was linear over a concentration range of 10–1000 ng/mL with correlation coefficient values >0.997. The method was validated with intra‐ and inter‐day accuracy (relative error) ranging from 1.79 to 9.17% and from 2.16 to 9.66%, respectively, and precision (coefficient of variation) ranged from 1.94 to 9.25% and from 2.37 to 10.08%, respectively. Short‐term stability, freeze–thaw stability and the processed sample stability tests were performed. This method was further applied to analyze γ‐tocotrienol plasma concentrations in rats at various time points after administration of a 2 mg/kg single intravenous dose, and a pharmacokinetic profile was successfully obtained. Copyright © 2012 John Wiley & Sons, Ltd.
Secoscabronine M, a novel diterpenoid from the Chinese bitter mushroom Sarcodon scabrosus
Authors: Shi Xin‐Wei , Zhang An‐Ling , Pescitelli Gennaro , Gao Jin‐Ming
Published: April 2012

Secoscabronine M (1) is a hemiacetal cyathane diterpenoid that was isolated from the fruiting bodies of the basidiomycete Sarcodon scabrosus (Fr.) Karst. Compound 1 possesses a novel structure with a bond cleavage between C‐3 and C‐4. The structure of the new compound was elucidated by means of spectroscopic methods, including two‐dimensional nuclear magnetic resonance experiments. The absolute configuration of 1 was established by analysis of circular dichroism spectroscopy and also by employing time‐dependent density functional theory calculations. In addition, compound 1 was confirmed to be an equilibrium mixture of two epimers (15S and 15R) at position C‐15 in polar solvents by one‐dimensional nuclear magnetic resonance analysis. Chirality 4:386–390, 2012. © 2012 Wiley Periodicals, Inc.
Comparison of Air Filter Tests under Real Life and Lab Conditions
Authors: Schmidt Frank , Breidenbach Achim , Däuber Eckhard
Published: April 2012

Aufgrund des neuen Entwurfs der EN 779 und der damit verbundenen Einführung eines Mindestwirkungsgrades ist erneut eine heftige Diskussion über die Verwertbarkeit der im Labor ermittelten Wirkungsgrade von Filtern insbesondere im Vergleich zu Betriebsergebnissen entfacht. Deshalb wurden im Rahmen dieser Studie Filter drei bzw. sechs Monate in einer Lüftungsanlage eingebaut. Diese im Realbetrieb gealterten Filter wurden im normkonformen Prüfstand einer DEHS‐Effizienzmessung unterzogen, d. h. Druckverluste und Wirkungsgrade wurden ermittelt und mit Werten im Neuzustand verglichen. Es erfolgten weitere Versuche am Filterelement, die auf unterschiedlichen Verfahren zur Entladung des Filters (Beaufschlagung mit Isopropanol, Tensiden und Dieselruß) beruhen.
Effect of Telmisartan on Paroxysmal Atrial Fibrillation Recurrence in Hypertensive Patients With Normal or Increased Left Atrial Size
Authors: Fogari Roberto , Zoppi Annalisa , Maffioli Pamela , Mugellini Amedeo , Preti Paola , Perrone Tiziano , Derosa Giuseppe
Published: April 2012

Background:

Hypertension is the most prevalent and potentially modifiable risk factor for atrial fibrillation (AF). In a previous secondary prevention study, the authors observed that the angiotensin II receptor blocker telmisartan was more effective than the calcium channel blocker amlodipine in preventing AF relapse in hypertensive patients with normal atrial size.

Hypothesis:

Telmisartan may be more effective than amlodipine in preventing AF recurrence in hypertensive patients with paroxysmal AF and normal or increased left atrial dimension (LAD).

Methods:

The authors assigned 378 mild hypertensive outpatients in sinus rhythm, but with ≥2 episodes of AF in the previous 6 months, to 1 of 2 groups. Group 1 comprised patients with LAD <40 mm in females and <45 mm in males. Group 2 comprised patients with LAD >40 mm and <45 mm in females and >45 mm and <50 mm in males. In both groups, patients were randomly treated with telmisartan or amlodipine for 1 year.

Results:

Systolic and diastolic blood pressure were similarly reduced by telmisartan and amlodipine in both groups. The AF recurrence rate was significantly lower in the telmisartan‐treated patients than in the amlodipine‐treated patients in both group 1 (12 vs 39, P < 0.01) and group 2 (40 vs 59, P < 0.05). Under telmisartan, the AF recurrence rate was significantly lower in group 1 than in group 2 (12.9% vs 42.1%, P < 0.05). Time to a first AF relapse was significantly longer with telmisartan than with amlodipine in both group 1 (176 ± 94 days vs 74 ± 61 days, P < 0.05) and group 2 (119 ± 65 days vs 38 ± 35 days, P < 0.05).

Conclusions:

Telmisartan was more effective than amlodipine in preventing AF recurrences in hypertensive patients with paroxysmal AF. Clin. Cardiol. 2012 DOI: 10.1002/clc.21994

The authors have no funding, financial relationships, or conflicts of interest to disclose.
Pubertal development predicts eating behaviors in adolescence
Authors: Baker Jessica H. , Thornton Laura M. , Lichtenstein Paul , Bulik Cynthia M.
Published: April 2012

Objective:

Early maturing girls are at increased risk for disordered eating. However, it is unclear if the association between puberty and disordered eating continues throughout pubertal development and if a similar association is exhibited in boys.

Method:

Participants included 1340 same‐ and 624 opposite‐sex twins from the Swedish Twin Study of Child and Adolescent Development. Pubertal development was assessed at age 13–14 with the pubertal development scale. General disordered eating, measured with the eating disorder inventory‐2 (EDI) was assessed at age 16–17, and dieting and purging behaviors were assessed at both ages 16–17 and 19–20. We applied analysis of variance and logistic regression analyses to determine whether pubertal development in early‐to‐mid adolescence predicted eating disorder‐related behaviors in late adolescence and young adulthood.

Results:

Pubertal development in early‐to‐mid adolescence was significantly associated with EDI scores and dieting in late adolescence. No significant association was observed between pubertal development and dieting and purging in young adulthood.

Discussion:

Complex combinations of cultural and biological influences likely converge during pubertal development increasing vulnerability to disordered eating. The impact of pubertal development on disordered eating appears to be limited to the adolescent period. © 2012 by Wiley Periodicals, Inc. (Int J Eat Disord 2012;45:819–826)
Route guidance by a car navigation system based on augmented reality
Authors: Akaho Kengo , Nakagawa Takashi , Yamaguchi Yoshihisa , Kawai Katsuya , Kato Hirokazu , Nishida Shogo
Published: April 2012

Car navigation systems play a prominent role in road traffic safety and traffic regulation. However, it is necessary to improve the route guidance of car navigation systems so that they accurately and quickly recognize small differences in location. Thus, to increase the ease of understanding and safety of car navigation systems, navigation systems based on augmented reality have been proposed for providing guidance at road intersections. We are currently developing a car navigation system based on augmented reality, called AR‐Navi. We investigated designs for the display of road intersection guidance that can be easily understood even when limited information is available and proposed a “best shot” display method that does not use moving images. In addition, we implemented a prototype system that includes these methods and conducted driving experiments on public roads to evaluate the ease of understanding and safety of AR‐Navi. Using the evaluation results, we confirmed that the ease of understanding and safety is similar in the case of AR‐Navi and CG‐Navi. We also clarified the characteristics of AR‐Navi. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 180(2): 43–54, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22278
Lanthanide‐Based Dinuclear Complexes Involving an o‐Quinone–Tetrathiafulvalene–o‐Quinone Bridging Ligand: X‐ray Structures, Magnetic and Photophysical Properties
Authors: Pointillart Fabrice , Kuropatov Viacheslav , Mitin Alexander , Maury Olivier , Le Gal Yann , Golhen Stéphane , Cador Olivier , Cherkasov Vladimir , Ouahab Lahcène
Published: April 2012

Six dinuclear complexes, [Ln2(hfac)6(H2O)2(L)] [Ln = Y (1) and Er (2)], [Yb2(hfac)6(L)] (3), [Ln2(tta)6(L)]·3CH2Cl2 [Ln = Y (4) and Er (5)] and [Yb2(tta)6(L)]·2C6H14 (6), have been prepared by coordination reactions between the [Ln(β‐diketonate)3]·2H2O (Ln = YIII, ErIII and YbIII; β‐diketonate = hfac– or tta–) building blocks and 4,4′,7,7′‐tetra‐tert‐butyl‐2,2′‐bi‐1,3‐benzodithiole‐5,5′,6,6′‐tetrone ligand (L), which acts as a bridge between the two metal centres. Their X‐ray structures reveal that the symmetries around the lanthanide atoms depend on the β‐diketonate anions and the size of the 4f ions. The dc magnetic measurements showed paramagnetic behaviour with thermal variations of the χMT products that depend on the crystal‐field symmetry around the 4f ions. The photophysical properties of the coordination complexes were studied by solid‐state absorption spectroscopy, and DFT calculations were carried out on the free ligand L and the diamagnetic YIII derivatives 1 and 4. Irradiation of the charge‐transfer (ILCT) band of L [λex = 700 nm (14285 cm–1)], 1 and 4 [λex = 750 nm (13335 cm–1)] induced weak fluorescence in L at 12500 cm–1 (for free L) and in 1 at 12200 cm–1, whereas in the case of 3, irradiation at 13335 cm–1 induced weak line‐shape emission assigned to the 2F5/2 → 2F7/2 (9880 cm–1) ytterbium‐centred transition. No residual charge‐transfer emission was observed in this last case attesting the efficient energy transfer from the excited charge‐transfer state to the 2F5/2 state. The weak intensity of the emissions should mainly be attributed to energy back‐transfer between the relaxed CT excited state and the CT state. Nevertheless, sensitisation of the YbIII luminescence in 3 was achieved through the lowest‐energy donor excited state (13585 cm–1) reported until now.
Conformational Preference in Bis(porphyrin) Tweezer Complexes: A Versatile Chirality Sensor for α‐Chiral Carboxylic Acids
Authors: Tanasova Marina , Borhan Babak
Published: April 2012

Metallated porphyrin tweezers have demonstrated a remarkable ability to function as reporters of absolute stereochemistry for a number of different classes of organic molecules. Flexibility in binding, however, can result in an ensemble of different Exciton Coupled Circular Dichroism (ECCD) active conformations that could lead to variable results. Linker flexibility was found to be a key determinant of binding conformation. Experimental results indicate that a balance between linker flexibility and rigidity could yield an optimum porphyrin tweezer that stabilizes a common conformation for all bound chiral guests. This leads to a more simplified approach to absolute stereochemical determination of asymmetry for small organic molecules. This was demonstrated by the use of a C3‐linked zincated porphyrin tweezer that yields a common conformational preference for a variety of α‐chiral carboxylic acids derivatized with a diamine carrier.
Voltammetry as a Reference Method in the Preparation Process of Plant Control Material Containing As, Pt and Tl
Authors: Kowalska Joanna , Giska Iwona , Jedynak Łukasz , Krasnodębska‐Ostręga Beata , Pałdyna Joanna , Sadowska Monika , Golimowski Jerzy
Published: April 2012

Voltammetric methods are very suitable and versatile techniques for the simultaneous metal determination in complex matrices after thorough mineralization. In the presented work, voltammetric methods were used as reference methods in the preparation process of control plant material. Determination of As, Pt, Tl and other elements (Cd, Cu, Pb, Zn) in plant material prepared in our laboratory is described. For quantitative determination of the elements two independent analytical methods were applied. To obtain plant material containing As, Pt and Tl white mustard (Sinapis alba L.) was hydroponically cultivated under controlled conditions in a nutrient solution with addition of As, Pt and Tl salts.
Multiplexed Ultrasensitive Determination of Adrenocorticotropin and Cortisol Hormones at a Dual Electrochemical Immunosensor
Authors: Moreno‐Guzmán María , González‐Cortés Araceli , Yáñez‐Sedeño Paloma , Pingarrón José M.
Published: April 2012

A novel dual electrochemical immunosensor for the multiplexed determination of adrenocorticotropin (ACTH) and cortisol is reported. Aminophenylboronic acid‐modified dual screen‐printed carbon electrodes were prepared on which the corresponding ACTH and cortisol antibodies were immobilized. Competitive immunoassays involved biotinylated ACTH and alkaline phosphatase labelled streptavidin, or alkaline phosphatase labelled cortisol. Differential pulse voltammetry upon 1‐naphtyl phosphate addition was employed to monitor the affinity reactions. The ranges of linearity were 5.0×10−5−0.1 and 0.1−500 ng/mL for ACTH and cortisol. The usefulness of the dual immunosensor was demonstrated by analyzing certified human serum samples with good recoveries.
Simplified universal method for determining electrolyte temperatures in a capillary electrophoresis instrument with forced‐air cooling
Authors: Patel Kevin H. , Evenhuis Christopher J. , Cherney Leonid T. , Krylov Sergey N.
Published: April 2012

Temperature increase due to resistive electrical heating is an inherent limitation of capillary electrophoresis (CE). Active cooling systems are used to decrease the temperature of the capillary, but their capacity is limited; and in addition, they leave “hot spots” at the detection interface and at the capillary ends. Until recently, the matter was complicated by the lack of a fast and generic method for temperature determination in efficiently and inefficiently cooled regions of the capillary. Our group recently introduced such a method, termed “Universal Method for determining Electrolyte Temperatures” (UMET). UMET is a probe‐less approach that requires only measuring current versus voltage for different voltages and processing the data using an iterative algorithm. Here, we apply UMET to develop a Simplified Universal Method of Temperature Determination (SUMET) for a CE instrument with a forced‐air cooling system using an Agilent 7100 CE instrument (Agilent Technologies, Saint Laurent, Quebec, Canada) as an example. We collected a wide set of empirical voltage–current data for a variety of buffers and capillary diameters. We further constructed empirical equations for temperature calculation in efficiently and inefficiently cooled parts of the capillary that require only the data from a single 1‐min voltage–current measurement. The equations are specific for the Agilent 7100 CE instrument (Agilent Technologies) but can be applied to all kinds of capillaries and buffers. Similar SUMET approaches can be developed for other CE instruments with forced‐air cooling using our approach.
Influence of molecular configuration and conformation on the electromigration of oligosaccharides in narrow bore capillaries
Authors: Mittermayr Stefan , Guttman András
Published: April 2012

Capillary electrophoresis enables fast, high efficiency separations of oligosaccharides, wherein positional and/or linkage isomers, bearing the same charge‐to‐mass ratio, can readily be separated based on hydrodynamic radius differences. Fundamental electrophoretic mobility theory was used to investigate the correlation between changes in hydrodynamic volume equivalent radius and corresponding electrophoretic characteristics of oligosaccharides with different molecular properties. Fluorescently derivatized isomeric malto‐, cello‐, and isomaltooligosaccharide ladders, differing only in their linkage type of α1→4, β1→4, and α1→6, respectively, as well as a sterically larger N‐acetylchitooligosaccharide ladder were used as model compounds. Mere differences in glycosidic linkage type or anomericity of isomeric oligo‐glucoses had a decisive impact on their electromigration behavior, thus reflecting discrepancies in hydrodynamic radii and associated molecular conformations. The impact of hydrogen bridges, and associated availability of hydroxyl groups, on the molecular conformations, was investigated by hydrophilic interaction liquid chromatography. The experimentally observed electrophoretic and chromatographic differences between isomeric oligo‐glucoses strongly suggested that special attention must be given when homooligosaccharide ladders are employed for normalization and comparability purposes, for example, in glucose unit calculation based structural elucidation.
The course of delirium in older long‐term care residents
Authors: Cole Martin G. , McCusker Jane , Voyer Philippe , Monette Johanne , Champoux Nathalie , Ciampi Antonio , Vu Minh , Belzile Eric
Published: April 2012

Objective

The purpose of this study was to determine the course of delirium in older long‐term care (LTC) residents.

Methods

A prospective cohort study of 279 residents in seven LTC facilities in Montreal and Quebec City, Canada, was conducted. The Mini Mental State Examination (MMSE), Confusion Assessment Method (CAM), Delirium Index (DI), Hierarchic Dementia Scale, Barthel Index, and Cornell Scale for Depression were completed at baseline. The MMSE, CAM, and DI were repeated weekly for 6 months. Information on medical problems and medication was abstracted from resident charts. Data were analyzed using descriptive statistics, Cox proportional hazard regression, and logistic regression.

Results

Of the 279 residents, 41 (14.7%) had 61 CAM‐defined incident episodes of delirium: 28 (10%) had one episode and 13 (4.7%) had two or more episodes. Episode duration was 7–63 days, mean, 11.3 (SD, 10.1) days. The mean episode DI score was 11.5 (SD, 3.5). Rates of recovery at 1, 2, 4, and 24 weeks were 57.4%, 67.2% 77.1%, and 80.3%, respectively. Most episodes were preceded or followed by one or more CAM core symptoms of delirium, sometimes lasting many weeks.

Conclusions

Confusion Assessment Method‐defined incident episodes of delirium in older LTC residents appear to last longer than episodes in acute care hospital patients, but rates of recovery at 4 and 24 weeks are similar. Notably, most episodes were preceded or followed by one or more CAM core symptoms of delirium. These findings have implications for clinical practice and research in LTC settings. Copyright © 2012 John Wiley & Sons, Ltd.
Chemokines and mitochondrial products activate neutrophils to amplify organ injury during mouse acute liver failure
Authors: Marques Pedro E. , Amaral Sylvia S. , Pires Daniele A. , Nogueira Laura L. , Soriani Frederico M. , Lima Braulio H.F. , Lopes Gabriel A.O. , Russo Remo C. , Ávila Thiago V. , Melgaço Juliana G. , Oliveira André G. , Pinto Marcelo A. , Lima Cristiano X. , De Paula Ana Maria , Cara Denise C. , Leite Maria F. , Teixeira Mauro M. , Menezes Gustavo Batista
Published: April 2012

Acetaminophen (APAP) is a safe analgesic and antipyretic drug. However, APAP overdose leads to massive hepatocyte death. Cell death during APAP toxicity occurs by oncotic necrosis, in which the release of intracellular contents can elicit a reactive inflammatory response. We have previously demonstrated that an intravascular gradient of chemokines and mitochondria-derived formyl peptides collaborate to guide neutrophils to sites of liver necrosis by CXC chemokine receptor 2 (CXCR2) and formyl peptide receptor 1 (FPR1), respectively. Here, we investigated the role of CXCR2 chemokines and mitochondrial products during APAP-induced liver injury and in liver neutrophil influx and hepatotoxicity. During APAP overdose, neutrophils accumulated into the liver, and blockage of neutrophil infiltration by anti–granulocyte receptor 1 depletion or combined CXCR2-FPR1 antagonism significantly prevented hepatotoxicity. In agreement with our

in vivo

data, isolated human neutrophils were cytotoxic to HepG2 cells when cocultured, and the mechanism of neutrophil killing was dependent on direct contact with HepG2 cells and the CXCR2-FPR1–signaling pathway. Also, in mice and humans, serum levels of both mitochondrial DNA (mitDNA) and CXCR2 chemokines were higher during acute liver injury, suggesting that necrosis products may reach remote organs through the circulation, leading to a systemic inflammatory response. Accordingly, APAP-treated mice exhibited marked systemic inflammation and lung injury, which was prevented by CXCR2-FPR1 blockage and Toll-like receptor 9 (TLR9) absence (TLR9−/− mice).

Conclusion:

Chemokines and mitochondrial products (e.g., formyl peptides and mitDNA) collaborate in neutrophil-mediated injury and systemic inflammation during acute liver failure. Hepatocyte death is amplified by liver neutrophil infiltration, and the release of necrotic products into the circulation may trigger a systemic inflammatory response and remote lung injury.
Natural killer p46High expression defines a natural killer cell subset that is potentially involved in control of hepatitis C virus replication and modulation of liver fibrosis
Authors: Krämer Benjamin , Körner Christian , Kebschull Moritz , Glässner Andreas , Eisenhardt Marianne , Nischalke Hans-Dieter , Alexander Michael , Sauerbruch Tilman , Spengler Ulrich , Nattermann Jacob
Published: April 2012

Natural killer (NK) cells play a role in the early control and natural course of hepatitis C virus (HCV) infection. NK cell function is regulated by a multitude of receptors, including activating NKp46 receptor. However, reports on NKp46 in hepatitis C are controversial. Therefore, we investigated the hepatic recruitment and function of NKp46(+) NK cells, considering differential surface expression of NKp46 resulting in NKp46High and NKp46Dim subsets. Intra- and extrahepatic NK-cell subsets from HCV-infected patients were characterized by flow cytometry. Cytotoxic activity and interferon-gamma (IFN-γ) secretion were studied using K-562, P815, and primary hepatic stellate cells as targets. Anti-HCV activity of NK-cell subsets was studied using the replicon system. Density of NKp46 surface expression clearly segregated NKp46Dim and NKp46High subsets, which differed significantly with respect to the coexpression of maturation markers and NK-cell receptors. More important, NKp46High NK cells showed a higher cytolytic activity and stronger IFN-γ secretion than NKp46Dim NK cells. Accordingly, NKp46High NK cells efficiently blocked HCV replication

in vitro

. Blocking experiments confirmed an important role for the NKp46 receptor. Furthermore, we found an intrahepatic accumulation of NKp46High NK cells. Of note, high cytolytic activity of NKp46High NK cells was also confirmed in the intrahepatic NK-cell population, and the frequency of intrahepatic NKp46High NK cells was inversely correlated with HCV-RNA levels and fibrosis stage.

Conclusions

: NKp46High expression defines a specific NK-cell subset that may be involved in both the suppression of HCV replication and HCV-associated liver damage underpinning the role of NK cells in the immunopathogenesis of HCV. (Hepatology 2012)
Protein arginine methyltransferase 1 regulates hepatic glucose production in a FoxO1-dependent manner
Authors: Choi Dahee , Oh Kyoung-Jin , Han Hye-Sook , Yoon Young-Sil , Jung Chang-Yun , Kim Seong-Tae , Koo Seung-Hoi
Published: April 2012

Postprandial insulin plays a critical role in suppressing hepatic glucose production to maintain euglycemia in mammals. Insulin-dependent activation of protein kinase B (Akt) regulates this process, in part, by inhibiting FoxO1-dependent hepatic gluconeogenesis by direct phosphorylation and subsequent cytoplasmic exclusion. Previously, it was demonstrated that protein arginine methyltransferase 1 (PRMT1)-dependent arginine modification of FoxO1 interferes with Akt-dependent phosphorylation, both in cancer cells and in the

Caenorhabditis elegans

model, suggesting that this additional modification of FoxO1 might be critical in its transcriptional activity. In this study, we attempted to directly test the effect of arginine methylation of FoxO1 on hepatic glucose metabolism. The ectopic expression of PRMT1 enhanced messenger RNA levels of FoxO1 target genes in gluconeogenesis, resulting in increased glucose production from primary hepatocytes. Phosphorylation of FoxO1 at serine 253 was reduced with PRMT1 expression, without affecting the serine 473 phosphorylation of Akt. Conversely, knockdown of PRMT1 promoted an inhibition of FoxO1 activity and hepatic gluconeogenesis by enhancing the phosphorylation of FoxO1. In addition, genetic haploinsufficiency of

Prmt1

reduced hepatic gluconeogenesis and blood-glucose levels in mouse models, underscoring the importance of this factor in hepatic glucose metabolism

in vivo

. Finally, we were able to observe an amelioration of the hyperglycemic phenotype of

db/db

mice with PRMT1 knockdown, showing a potential importance of this protein as a therapeutic target for the treatment of diabetes.

Conclusion:

Our data strongly suggest that the PRMT1-dependent regulation of FoxO1 is critical in hepatic glucose metabolism

in vivo

. (Hepatology 2012)
Healthcare financing in Yemen
Authors: Holst Jens , Gericke Christian A.
Published: April 2012

Yemen is a low‐middle‐income country where more than half of the population live in rural areas and lack access to the most basic health care. At US$40 per capita, Yemen's annual total health expenditure (THE) is among the lowest worldwide. This study analyses the preconditions and options for implementing basic social health protection in Yemen. It reveals a four‐tiered healthcare system characterised by high geographic and financial access barriers mainly for the poor. Out‐of‐pocket payments constitute 55% of THE, and cost‐sharing exemption schemes are not well organised. Resource‐allocation practices are inequitable because about 30% of THE gets spent on treatment abroad for a small number of patients, mainly from better‐off families. Against the background of a lack of social health protection, a series of small‐scale and often informal solidarity schemes have developed, and a number of public and private companies have set up health benefit schemes for their employees. Employment‐based schemes usually provide reasonable health care at an average annual cost of YR44 000 (US$200) per employee. In contrast, civil servants contribute to a mandatory health‐insurance scheme without receiving any additional health benefits in return. A number of options for initiating a pathway towards a universal health‐insurance system are discussed. Copyright © 2012 John Wiley & Sons, Ltd.
A population‐based study of human papillomavirus genotype prevalence in the United States: Baseline measures prior to mass human papillomavirus vaccination
Authors: Wheeler Cosette M. , Hunt William C. , Cuzick Jack , Langsfeld Erika , Pearse Amanda , Montoya George D. , Robertson Michael , Shearman Catherine A. , Castle Philip E. ,   For The New Mexico HPV Pap Registry Steering Committee
Published: April 2012

Currently, two prophylactic human papillomavirus (HPV) vaccines targeting HPV 16 and 18 have been shown to be highly efficacious for preventing precursor lesions although the effectiveness of these vaccines in real‐world clinical settings must still be determined. Toward this end, an ongoing statewide surveillance program was established in New Mexico to assess all aspects of cervical cancer preventive care. Given that the reduction in cervical cancer incidence is expected to take several decades to manifest, a systematic population‐based measurement of HPV type‐specific prevalence employing an age‐ and cytology‐stratified sample of 47,617 women attending for cervical screening was conducted prior to widespread HPV vaccination. A well‐validated polymerase chain reaction (PCR) method for 37 HPV genotypes was used to test liquid‐based cytology specimens. The prevalence for any of the 37 HPV types was 27.3% overall with a maximum of 52% at age of 20 years followed by a rapid decline at older ages. The HPV 16 prevalences in women aged ≤20 years, 21–29 years or ≥30 years were 9.6, 6.5 and 1.8%, respectively. The combined prevalences of HPV 16 and 18 in these age groups were 12.0, 8.3 and 2.4%, respectively. HPV 16 and/or HPV 18 were detected in 54.5% of high‐grade squamous intraepithelial (cytologic) lesions (HSIL) and in 25.0% of those with low‐grade SIL (LSIL). These baseline data enable estimates of maximum HPV vaccine impact across time and provide critical reference measurements important to assessing clinical benefits and potential harms of HPV vaccination including increases in nonvaccine HPV types (i.e., type replacement).
SOCS‐1 gene delivery cooperates with cisplatin plus pemetrexed to exhibit preclinical antitumor activity against malignant pleural mesothelioma
Authors: Iwahori Kota , Serada Satoshi , Fujimoto Minoru , Ripley Barry , Nomura Shintaro , Mizuguchi Hiroyuki , Shimada Kazuki , Takahashi Tsuyoshi , Kawase Ichiro , Kishimoto Tadamitsu , Naka Tetsuji
Published: April 2012

Malignant pleural mesothelioma (MPM) is an aggressive tumor with poor prognosis for which an effective therapy remains to be established. This study investigated the therapeutic potential of gene delivery using suppressor of cytokine signaling 1 (SOCS‐1), an endogenous inhibitor of intracellular signaling pathways, for the treatment of MPM. We infected MPM cells (MESO‐4, H28 and H226) with adenovirus‐expressing SOCS‐1 vector to examine the effect of SOCS‐1 overexpression on MPM cells. We evaluated the antitumor effect of SOCS‐1 gene delivery combined with cisplatin plus pemetrexed by cell proliferation, apoptosis and invasion assay. We also investigated the regulation of NF‐κB and STAT3 signaling related to apoptotic pathways. Furthermore, we evaluated the inhibition of tumor growth by SOCS‐1 gene delivery combined with cisplatin plus pemetrexed in vivo. SOCS‐1 gene delivery cooperated with cisplatin plus pemetrexed to inhibit cell proliferation, invasiveness and induction of apoptosis in MPM cells. SOCS‐1 regulated NF‐κB and STAT3 signaling to induce apoptosis in MESO‐4 and H226 cells. Furthermore, SOCS‐1 gene delivery cooperated with cisplatin plus pemetrexed to regulate NF‐κB signaling and significantly inhibit tumor growth of MPM in vivo. These results suggest that SOCS‐1 gene delivery has a potent antitumor effect against MPM and a potential for clinical use in combination with cisplatin plus pemetrexed.
Stirred flow bioreactor modulates chondrocyte growth and extracellular matrix biosynthesis in chitosan scaffolds
Authors: García Cruz Dunia Mercedes , Salmerón‐Sánchez Manuel , Gómez‐Ribelles José Luis
Published: April 2012

The aim of this study is to show the favorable effect of simple dynamic culture conditions on chondrogenesis of previously expanded human chondrocytes seeded in a macroporous scaffold with week cell‐pore walls adhesion. We obtained enhanced chondrogenesis by the combination of chitosan porous supports with a double micro‐ and macro‐pore structure and cell culture in a stirring bioreactor. Cell‐scaffold constructs were cultured under static or mechanically stimulated conditions using an intermittent stirred flow bioreactor during 28 days. In static culture, the chondrocytes were homogeneously distributed throughout the scaffold pores; cells adhered to the scaffold pore walls, showed extended morphology and were able to proliferate. Immunofluorescense and biochemical assays showed abundant type I collagen deposition at day 28. However, the behavior of chondrocytes submitted to mechanical stimuli in the bioreactor was completely different. Mechanical loading influenced cell morphology and extracellular matrix composition. Under dynamic conditions, chondrocytes kept their characteristic phenotype and tended to form cell aggregates surrounded by a layer of the main components of the hyaline cartilage extracellular matrix, type II collagen, and aggrecan. An enhanced aggrecan and collagen type II production was observed in engineered cartilage constructs cultured under stirred flow compared with those cultured under static conditions. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 100A: 2330–2341, 2012.