bluuebunny/crossref_metadata_2025 huggingface dataset:
Autotaxin: Its Role in Biology of Melanoma Cells and as a Pharmacological Target
Authors: Jankowski Maciej
Published: March 2011

Autotaxin (ATX) is an extracellular lysophospholipase D (lysoPLD) released from normal cells and cancer cells. Activity of ATX is detected in various biological fluids. The lysophosphatidic acid (LPA) is the main product of ATX. LPA acting through specific G protein-coupled receptors (LPA1-LPA6) affects immunological response, normal development, and malignant tumors' formation and progression. In this review, the impact of autotoxin on biology of melanoma cells and potential treatment is discussed.
Implementation of a Tool to Modify Behavior in a Chronic Disease Management Program
Authors: Gillespie Nicole D. , Lenz Thomas L.
Published: March 2011

Chronic diseases like diabetes, hypertension, and dyslipidemia continue to be a significant burden on the US health care system. As a result, many healthcare providers are implementing strategies to prevent the incidence of heart disease and other chronic conditions. Among these strategies are proper drug therapy and lifestyle modifications. Behavior change is often the rate-limiting step in the prevention and maintenance of lifestyle modifications. The purpose of this paper is to describe a tool used to guide the progression and assess the effectiveness of a cardiovascular risk reduction program. The tool uses the Transtheoretical Model of Behavior Change to determine the readiness and confidence to change specific lifestyle behaviors pertinent to cardiovascular health. The tool aids the practitioner in developing a patient-centered plan to implement and maintain lifestyle changes and can be tailored to use in any situation requiring a behavior change on the part of the patient.
Beneficial Regulation of Matrix Metalloproteinases for Skin Health
Authors: Philips Neena , Auler Susan , Hugo Raul , Gonzalez Salvador
Published: March 2011

Matrix metalloproteinases (MMPs) are essential to the remodeling of the extracellular matrix. While their upregulation facilitates aging and cancer, they are essential to epidermal differentiation and the prevention of wound scars. The pharmaceutical industry is active in identifying products that inhibit MMPs to prevent or treat aging and cancer and products that stimulate MMPs to prevent epidermal hyperproliferative diseases and wound scars.
The Roles of ADAMs Family Proteinases in Skin Diseases
Authors: Kawaguchi Masakazu , Hearing Vincent J.
Published: March 2011

A disintegrin and metalloproteinases (ADAMs) are members of a new gene family of transmembrane and secreted proteins, which belong to the zinc proteinase superfamily. These molecules are involved in various biological events such as cell adhesion, cell fusion, cell migration, membrane protein shedding, and proteolysis. Growing evidence now attests to the potential involvement of ADAMs proteinases in diverse processes such as skin wound healing, inflammation, pigmentation, tumor development, cell proliferation, and metastasis. This paper focuses on the roles of ADAMs proteinases in a wide variety of skin diseases.
Differential Effects of Dopaminergic Therapies on Dorsal and Ventral Striatum in Parkinson's Disease: Implications for Cognitive Function
Authors: MacDonald Penny A. , Monchi Oury
Published: March 2011

Cognitive abnormalities are a feature of Parkinson's disease (PD). Unlike motor symptoms that are clearly improved by dopaminergic therapy, the effect of dopamine replacement on cognition seems paradoxical. Some cognitive functions are improved whereas others are unaltered or even hindered. Our aim was to understand the effect of dopamine replacement therapy on various aspects of cognition. Whereas dorsal striatum receives dopamine input from the substantia nigra (SN), ventral striatum is innervated by dopamine-producing cells in the ventral tegmental area (VTA). In PD, degeneration of SN is substantially greater than cell loss in VTA and hence dopamine-deficiency is significantly greater in dorsal compared to ventral striatum. We suggest that dopamine supplementation improves functions mediated by dorsal striatum and impairs, or heightens to a pathological degree, operations ascribed to ventral striatum. We consider the extant literature in light of this principle. We also survey the effect of dopamine replacement on functional neuroimaging in PD relating the findings to this framework. This paper highlights the fact that currently, titration of therapy in PD is geared to optimizing dorsal striatum-mediated motor symptoms, at the expense of ventral striatum operations. Increased awareness of contrasting effects of dopamine replacement on dorsal versus ventral striatum functions will lead clinicians to survey a broader range of symptoms in determining optimal therapy, taking into account both those aspects of cognition that will be helped versus those that will be hindered by dopaminergic treatment.
Prevalence of Elevated Blood Pressure and Association with Obesity in Egyptian School Adolescents
Authors: Abolfotouh Mostafa A. , Sallam Sunny A. , Mohammed Mohammed S. , Loutfy Amany A. , Hasab Ali A.
Published: March 2011

Aim. To investigate the relationship between high blood pressure (HBP) and obesity in Egyptian adolescents.Methods. A cross-sectional study of 1500 adolescents (11–19 years) in Alexandria, Egypt, was conducted. Resting BP was measured and measurements were categorized using the 2004 fourth report on blood pressure screening recommendations. Additional measures included height, weight, and waist and hip circumferences. Obesity was determined based on BMI, waist circumference (WC) and waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR) indicators. Crude and adjusted odds ratios were used as measures of association between BP and obesity.Results. Prevalence rates of prehypertension and hypertension were 5.7% and 4.0%, respectively. Obesity was seen in 34.6%, 16.1%, 4.5%, and 16.7% according to BMI, WHR, WC, and WHtR, respectively. Adjusting for confounders, HBP was significantly associated with overall obesity based on BMI (OR=2.18, 95%,CI=1.38-3.44) and central obesity based on WC(OR=3.14, 95%,CI=1.67-5.94).Conclusion. Both overall obesity and central obesity were significant predictors of HBP in Egyptian adolescents.
Merkel cell tumor of the skin treated with localized radiotherapy: are widely negative margins required?
Authors: Trombetta Mark , Packard Matthew , Velosa Claudia , Silverman Jan , Werts Day , Parda David
Published: March 2011

Merkel's cell carcinoma is a rare cutaneous tumor that can affect a wide variety of sites throughout the body. Commonly, it affects the skin alone and the management of limited disease can be confusing since the natural history of the disease involves distant metastasis. Traditional management has required wide local excision with negative margins of resection. We describe a case treated with local therapy alone and review the literature to suggest that complete microscopic excision may not be required if adjuvant radiotherapy is used.
On Complemented Subspaces of Non-Archimedean Power Series Spaces
Authors: Śliwa Wiesław , Ziemkowska Agnieszka
Published: March 2011

The non-archimedean power series spaces, A1(a) and A∞(b), are the best known and most important examples of non-archimedean nuclear Fréchet spaces. We prove that the range of every continuous linear map from Ap(a) to Aq(b) has a Schauder basis if either p = 1 or p = ∞ and the set Mb,a of all bounded limit points of the double sequence (bi/aj )i, j∈ℕ is bounded. It follows that every complemented subspace of a power series space Ap(a) has a Schauder basis if either p = 1 or p = ∞ and the set Ma,a is bounded.
Inequalities for Eigenvalues of a General Clamped Plate Problem
Authors: Ghanbari K. , Shekarbeigi B.
Published: March 2011

Let D be a connected bounded domain in ℝn. Let 0 < μ1 ≤ μ2 ≤ … ≤ μk ≤ … be the eigenvalues of the following Dirichlet problem:

where V(x) is a nonnegative potential, and is positive. We prove the following inequalities:
Kiguradze-type Oscillation Theorems for Second Order Superlinear Dynamic Equations on Time Scales
Authors: Baoguo Jia , Erbe Lynn , Peterson Allan
Published: March 2011

Consider the second order superlinear dynamic equation

wherep∈C(, ℝ),is a time scale,ƒ: ℝ → ℝ is continuously differentiable and satisfiesƒ′(x) > 0, andx ƒ(x) > 0 forx≠ 0. Furthermore,f(x) also satisfies a superlinear condition, which includes the nonlinear functionƒ(x) =xαwith α > 1, commonly known as the Emden–Fowler case. Here the coefficient functionp(t) is allowed to be negative for arbitrarily large values oft. In addition to extending the result of Kiguradze for (∗) in the real case= ℝ, we obtain analogues in the difference equation andq-difference equation cases.
Tendencias de los diarios digitales en Perú
Authors: Yezers´ka Lyudmyla
Published: March 2011

Este artículo analiza algunas de las tendencias del desarrollo de los medios digitales en Perú. Para ello, se presentan los resultados obtenidos mediante una encuesta realizada a los responsables de las redacciones digitales de los periódicos nacionales de información general que, al finalizar la primera década de la existencia del ciberperiodismo en país (1995-2005), tenían ediciones en internet. Desde una perspectiva histórica, diferentes etapas de la evolución y consolidación de las ediciones diarias peruanas en internet, no han tenido una delimitación temporal definida. Cada medio ha avanzado a su ritmo, dependiendo –entre otros factores– del momento de entrada en la Red, del personal destinado a la publicación y, sobre todo, de la solidez de la empresa periodística y su política respecto a la edición digital. En relación con la presencia en internet, los diarios digitales han manifestado un crecimiento constante y numeroso, a lo largo de la primera década (1995-2005).
El montaje audiovisual como base narrativa para el cine documental interactivo: nuevos estudios
Authors: Porto Renó Denis
Published: March 2011

Este artículo presenta una revisión bibliográfica y los resultados del experimento-piloto de la investigación de doctorado “el montaje audiovisual como lenguaje narrativo para el cine documental interactivo”, que defiende la tesis de que hay características interactivas en el montaje audiovisual del cine, incluso como agente causador de la interactividad. La búsqueda de formatos audiovisuales interactivos están presentes en pesquisas internacionales, pero con miradas tecnológicas. Creemos que con la conclusión de este trabajo será posible proponer formatos de producción audiovisual interactiva para el cine, el vídeo, la televisión, el computador y el teléfono móvil, atendiendo las expectativas de la sociedad post-moderna.
La evolución del código cromático de las portadas de Abc, 1936-1939
Authors: Pérez Cuadrado Pedro
Published: March 2011

En 1936, Abc era un diario que editaba de forma notable y a todo color su edición dominical. El periódico imprimía ya entonces con dos sistemas diferentes –tipografía y huecograbado– y estaba a la vanguardia tecnológica. Este trabajo de investigación pretende, en primera instancia,  documentar cómo el diario español había llegado a alcanzar tal nivel de calidad y cómo, a partir de ésta, establece los procesos de estampación en color (tricromía primero y cuatricromía después) de forma regular y por primera vez en España para un medio de comunicación.
En la misma línea, se pretende hacer especial hincapié en los significados que el color propone en un medio impreso a mediados del siglo XX (todavía faltan más de 60 años para que el color sea una constante en la prensa diaria española) y cómo la guerra civil influiría de forma radical en este proceso: primero, para modificar los lenguajes de color en la estética belicista dominante y, por último, para hacerlo desaparecer definitivamente por razones obvias.
Imaging in Laryngeal Tumors
Authors: Varma Ravi , Jain Sanjay N
Published: March 2011

Imaging plays an important role in the diagnostic evaluation of laryngeal cancers. This article discusses important technical issues related to cross-sectional imaging modalities, imaging anatomy, patterns of tumor spread and the contribution of imaging in pretreatment staging and post-treatment surveillance.
Treatment Decision in the Management of Laryngeal Cancer: An Overview
Authors: Kannan R , Pradhan Sultan A
Published: March 2011

A spectrum of treatment plans and surgical procedures are available for management of laryngeal cancer. Transoral laser resection has proved an effective, minimally invasive and functionally satisfactory procedure for management of suitable T1 and T2 glottic cancers, and stage I-III supraglottic cancers. Introduction of chemoradiotherapy has also made great impact on the laryngeal preservation. The treatment of laryngeal cancer should be individualized according to the size and extent of the tumor, the age and physical condition of the patient, and the skill and experience of the surgeon with various treatment modalities and surgical procedures.
Near-total Laryngectomy
Authors: Pai Prathamesh S , Pradhan Sultan A
Published: March 2011

Dr. Bruce Pearson described near-total laryngectomy (NTL) in 19811a procedure which creates a biological shunt between the airway and the neopharynx to restore speech. Unlike other biological shunts, this is a dynamic myomucosal shunt which has universal applicability as seen by various series published from around the world.2-11We feel that the NTL procedure is oncologically safe and can provide a serviceable, prosthesis free voice and should be considered as a sound treatment option in advanced but lateralized cancers of the laryngopharynx. NTL has been described extensively in literature but we would like to highlight in this technical note a few modifications which we have found to be suitable and easily applicable by surgeons who regularly perform a total laryngectomy. We feel strongly that each and every surgeon who intends to treat laryngopharyngeal cancer should be well versed in this technique. A NTL shunt performed in a suitable patient gives the ability to phonate at will and makes the patient independent of a medical professional since the shunt is permanent and maintenance free.
Liberal Use of Pectoralis Major Muscle Flap Reduces Incidence of Pharyngocutaneous Fistula Following Salvage Laryngectomy
Authors: Souza Chris de , Chaturvedi Pankaj , Kale Shriketan
Published: March 2011

Patients undergoing salvage laryngectomy following chemoradiotherapy are more vulnerable to develop pharyngocutaneous fistula. This is due to fibrosis and reduced vascularity that results in poor postoperative healing. We are presenting a simple technique that can reduce this distressing complication. In patients where primary closure cannot be achieved, myocutaneous flap to reconstruct the pharynx reduces the incidence of postoperative complications. Similarly, buttressing of the suture line with the pectoralis major myofacial flap has been shown to reduce the fistula rates. Needless to say that pectoralis major muscle flap is a robust flap with acceptable complication rates.
Multi-scale interactions of geological processes during mineralization: cascade dynamics model and multifractal simulation
Authors: Yao L. , Cheng Q.
Published: March 2011

Abstract. Relations between mineralization and certain geological processes are established mostly by geologist's knowledge of field observations. However, these relations are descriptive and a quantitative model of how certain geological processes strengthen or hinder mineralization is not clear, that is to say, the mechanism of the interactions between mineralization and the geological framework has not been thoroughly studied. The dynamics behind these interactions are key in the understanding of fractal or multifractal formations caused by mineralization, among which singularities arise due to anomalous concentration of metals in narrow space. From a statistical point of view, we think that cascade dynamics play an important role in mineralization and studying them can reveal the nature of the various interactions throughout the process. We have constructed a multiplicative cascade model to simulate these dynamics. The probabilities of mineral deposit occurrences are used to represent direct results of mineralization. Multifractal simulation of probabilities of mineral potential based on our model is exemplified by a case study dealing with hydrothermal gold deposits in southern Nova Scotia, Canada. The extent of the impacts of certain geological processes on gold mineralization is related to the scale of the cascade process, especially to the maximum cascade division number nmax. Our research helps to understand how the singularity occurs during mineralization, which remains unanswered up to now, and the simulation may provide a more accurate distribution of mineral deposit occurrences that can be used to improve the results of the weights of evidence model in mapping mineral potential.
Production of Lentiviral Vectors in Protein‐free Media
Authors: Kuroda Hitoshi , Marino Michael P. , Kutner Robert H. , Reiser Jakob
Published: March 2011

The use of lentiviral vectors for transgene delivery in vitro and in vivo for applications in neuroscience, hematology, developmental biology, stem cell biology, and transgenesis has become commonplace. Lentiviral vectors provide an attractive toolfor transgene delivery in part because of their ability to incorporate(integrate)into the genomic DNA of target cells with high efficiency, especially in cells thatare not actively dividing. In addition, lentiviral vector‐mediated transgeneexpression can be maintained for long periods of time. In this unit, we describe protocols for lentiviral vector production in protein‐free media using polyethylenimine (PEI)‐mediated transfection, resulting in consistent lentiviral vector stocks. Such stocks are then concentrated by ultracentrifugation. We also provide reliable QPCR protocols to titrate lentiviral vectors based on vector DNA copies present in genomic DNA extracted from transduced cells. The vector production and titration protocol described here can be completed within 8 days. Curr. Protoc. Cell Biol. 50:26.8.1‐26.8.13. © 2011 by John Wiley & Sons, Inc.
Hyperostosis frontalis interna: What does it tell us about our health?
Authors: MAY Hila , Peled Nathan , Dar Gali , Abbas Janan , Hershkovitz Israel
Published: March 2011

Objectives: To examine whether the prevalence and severity of hyperostosis frontalis interna (HFI) has significantly changed during the past 100 years.

Methods: Two female populations, 100 years apart, were studied; 992 historic and 568 present day females. Detection of HFI was carried out via direct observation or CT images (Brilliance 64, Philips Medical Systems, Cleveland, Ohio). HFI was graded according to Hershkovitz et al.'s (1999) 4‐scale definition and according May et al.'s (2010c) 3‐scale definition.

Results: Following correction for age, present day females manifested a significantly higher HFI prevalence compared with historic females (P < 0.05). The risk of developing HFI was found to be approximately 2.5 times greater in present day females compared with females living 100 years ago (P < 0.05). In the young age cohort, present day females manifested a significantly higher prevalence of HFI type B (P < 0.05), whereas in the old age cohort, a significant difference in the prevalence of HFI types C and D was noted between the two groups (P < 0.05). HFI tended to appear at a younger age in the present population. The last two decades has witnessed an increase in HFI prevalence (from 55.6% to 75%).

Conclusions: HFI prevalence has increased during the last century, especially among young individuals, possibly indicating a profound change in human fertility patterns, together with the introduction of various hormonal treatments) and new dietary habits. Am. J. Hum. Biol., 2011. © 2011 Wiley‐Liss, Inc.
Treatment of intracerebral hemorrhage in animal models: Meta‐analysis
Authors: Frantzias Joseph , Sena Emily S. , Macleod Malcolm R. , Salman Rustam Al‐Shahi
Published: March 2011

Objective

Interventions that improve functional outcome after acute intracerebral hemorrhage (ICH) in animals might benefit humans. Therefore, we systematically reviewed the literature to find studies of nonsurgical treatments tested in animal models of ICH.

Methods

In July 2009 we searched Ovid Medline (from 1950), Embase (from 1980), and ISI Web of Knowledge (from 1969) for controlled animal studies of nonsurgical interventions given after the induction of ICH that reported neurobehavioral outcome. We assessed study quality and performed meta‐analysis using a weighted mean difference random effects model.

Results

Of 13,343 publications, 88 controlled studies described the effects of 64 different medical interventions (given a median of 2 hours after ICH induction) on 38 different neurobehavioral scales in 2,616 treated or control animals (median 14 rodents per study). Twenty‐seven (31%) studies randomized treatment allocation, and 7 (8%) reported allocation concealment; these studies had significantly smaller effect sizes than those without these attributes (p < 0.001). Of 64 interventions stem cells, calcium channel blockers, anti‐inflammatory drugs, iron chelators, and estrogens improved both structural outcomes and neurobehavioral scores in >1 study. Meta‐regression revealed that together, structural outcome and the intervention used accounted for 65% of the observed heterogeneity in neurobehavioral score (p < 0.001, adjusted r2 = 0.65).

Interpretation

Further animal studies of the interventions that we found to improve both functional and structural outcomes in animals, using better experimental designs, could target efforts to translate effective treatments for ICH in animals into randomized controlled trials in humans. Ann Neurol 2011
Alumina nanofibers obtained from poly(vinyl alcohol)/boehmite nanocomposites
Authors: Nakane Koji , Seto Mikita , Irie Satoshi , Ogihara Takashi , Ogata Nobuo
Published: March 2011

Poly(vinyl alcohol) (PVA)/boehmite nanocomposite (precursor) nanofibers were formed by electrospinning using a PVA aqueous solution of dispersed boehmite nanoparticles as the spinning solution. The alumina nanofibers were obtained by calcination of the precursor nanofibers between 500 and 1200°C. The specific surface area of the precursor nanofibers was around 6 m2/g, and that of the γ‐alumina nanofibers calcined at 500°C was around 300 m2/g. The specific surface areas and the fiber diameters were not affected by the alumina contents in the precursors. Also, the diameter of the alumina nanofibers was not affected by the calcination temperature of the precursor nanofibers. The pore characteristics of the alumina nanofibers decreased with increased calcination temperature due to the sintering, and nonporous α‐alumina nanofibers were obtained by calcination of the precursor nanofibers at 1200°C. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Effect of multistratification and film depth on the visualized dynamic sorption behavior of perylene in cellulose acetate films by a confocal laser scanning microscope technique
Authors: Hasegawa Takashi , Matsumoto Kiyoshi , Matsui Toshiro
Published: March 2011

The sorption behavior of a fluorescent reagent into a polymer film was visualized by confocal laser scanning microscopy (CLSM), and the effects of the additives, film types, and film depth on the diffusion coefficient (D) of the fluorescence reagent were examined. Perylene and cellulose acetate (CA) were used as a fluorescent reagent and a polymer material, respectively. Perylene dissolved in the additives triethylene glycol diacetate (TEGDA) and glycerol triacetate (GTA) was added to the CA film. Then, the evaluation of two types of CA films, a closed‐system cellulose acetate (CCA) sample and an open‐system cellulose acetate (OCA) sample, was conducted. At optimized CLSM conditions (with a scanning range at a 20‐μm depth from the CA film surface with 1‐μm intervals and a scanning speed of 1 fps), the sorption of perylene at the inner CA film was determined. The D values of perylene in the CA film were calculated pursuant to Fick's second law. Higher D values of perylene mixed with TEGDA versus those of perylene mixed with GTA were commonly obtained for the CCA sample (TEGDA: 8.9 × 10−15 m2/s > GTA: 1.7 × 10−15 m2/s) and the OCA sample (TEGDA: 11 × 10−15 m2/s > GTA: 3.3 × 10−15 m2/s) because of the higher chemical affinity of TEGDA with perylene than that of GTA. Perylene indicated a higher D value and was homogeneously distributed in the case of the OCA sample; we found that diffusivity and distribution of perylene in CA film were largely affected by the multistratification treatment. We also proved that the deeper the film depth was, the lower the diffusivity of perylene was, regardless of the types of additives and films. The factors considered for the film‐depth dependence of D were a gradual increase in the diffusion pathway for perylene caused by additive diffusion and the concentration dependence of the perylene D. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Electrical behavior of polyurethane derived from polyols synthesized with glycerol, phthalic anhydride, and oleic acid
Authors: Velayutham T. S. , Abd Majid W. H. , Gan S. N.
Published: March 2011

The direct current (DC) and alternating current (AC) conductivity of polyurethane (PUR) derived from polyols synthesized with glycerol, phthalic anhydride, and oleic acid were investigated in this article. The PUR was prepared by varying the oleic acid content in polyol (28, 40, and 65%) and the NCO/OH ratio of the PUR was varied to 1.2, 1.4, and 1.6. The electrical conduction studied by measuring the dependence of current on the applied field and temperature. Electrical conductivity in PUR was expressed by Arrhenius relations and the activation energies were calculated. Moreover, hyperbolic sine function was used to determine the conduction mechanism in PUR. It's presumed that the conduction mechanism was assisted by ions for the PUR which were contributed by oleic acid due to dissociation of protons and highly polar urethane groups in PUR. Furthermore, the dielectric behaviors of the material have been measured at room temperature in the frequency range of 100 Hz to 40 MHz. The frequency‐dependent conductivity of PUR materials has been analyzed using a Jonscher's power law expression and the plot exhibits the typical behavior of ionic materials, i.e., the DC plateau and the frequency dependent region. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Some properties of bacterial cellulose produced by new native strain Gluconacetobacter sp. A06O2 obtained from Turkish vinegar
Authors: Karahan Aynur Gül , Akoğlu Aylin , Çakır İbrahim , Kart Arzu , Çakmakçı M. Lütfü , Uygun Ayşegül , Göktepe Fatma
Published: March 2011

The aim of the study was to isolate and identify an acetic acid bacterial strain having high cellulose yield and to investigate some physicochemical properties of bacterial cellulose (BC). Acetic acid bacteria were isolated by using 62 samples (vinegar, fruit, vegetable, and soil) from different region of Turkey. The cellulose production ability of 153 isolates was determined. A strain (A06O2) having high and stable cellulose yield was identified by biochemical tests and 16S rRNA gene sequencing and compared with type strain Gluconacetobacter xylinus NRRL B‐759. Based on the results, strain A06O2 was named at the genus level as Gluconacetobacter, however, species level identification could not be made. Celluloses from both strains were purified to investigate the physicochemical properties such as thermal properties, solubility in various solvents, elemental composition, tensile properties, and surface properties by FTIR and SEM. The results showed that the cellulose samples of two bacterial strains differed in the physicochemical properties. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Nickel‐Catalyzed Allylic Substitution of Simple Alkenes
Authors: Matsubara Ryosuke , Jamison Timothy F.
Published: March 2011

This report describes a nickel‐catalyzed allylic substitution process of simple alkenes whereby an important structural motif, a 1,4‐diene, was prepared. The key to success is the use of an appropriate nickel–phosphine complex and a stoichiometric amount of silyl triflate. Reactions of 1‐alkyl‐substituted alkenes consistently provided 1,1‐disubstituted alkenes with high selectivity. Insight into the reaction mechanism as well as miscellaneous application of the developed catalytic process is also documented.
What is the most appropriate LCA method for measuring greenhouse gas emissions from bioenergy?
Authors: Aylott Matthew , Higson Adrian , Evans Geraint , Hamer Alison , Mortimer Nigel
Published: March 2011

Life cycle assessment (LCA) has become a vital tool in determining the sustainability of bioenergy. Matthew Aylott, Adrian Higson, Geraint Evans, Alison Hamer – from the UK's National Non‐Food Crops Centre – and Nigel Mortimer – North Energy Associates – explain how the assumptions we make and the method by which emissions are allocated in LCAs can have serious impacts on the conclusions we come to; conclusions which will shape the growth of the bioenergy sector. Copyright © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd
From songs to synapses: Molecular mechanisms of birdsong memory
Authors: Moorman Sanne , Mello Claudio V. , Bolhuis Johan J.
Published: March 2011

There are remarkable behavioral, neural, and genetic similarities between the way songbirds learn to sing and human infants learn to speak. Furthermore, the brain regions involved in birdsong learning, perception, and production have been identified and characterized in detail. In particular, the caudal medial nidopallium (the avian analog of the mammalian auditory‐association cortex) has been found to contain the neural substrate of auditory memory, paving the way for analyses of the underlying molecular mechanisms. Recently, the zebra finch genome was sequenced, and annotated cDNA databases representing over 15,000 unique brain‐expressed genes are available, enabling high‐throughput gene expression analyses. Here we review the involvement of immediate early genes (e.g. zenk and arc), their downstream targets (e.g. synapsins), and their regulatory signaling pathways (e.g. MAPK/ERK) in songbird memory. We propose that in‐depth investigations of zenk‐ and ERK‐dependent cascades will help to further unravel the molecular basis of auditory memory.
Does constructive neutral evolution play an important role in the origin of cellular complexity?
Authors: Speijer Dave
Published: March 2011

Recently, constructive neutral evolution has been touted as an important concept for the understanding of the emergence of cellular complexity. It has been invoked to help explain the development and retention of, amongst others, RNA splicing, RNA editing and ribosomal and mitochondrial respiratory chain complexity. The theory originated as a welcome explanation of isolated small scale cellular idiosyncrasies and as a reaction to ‘overselectionism’. Here I contend, that in its extended form, it has major conceptual problems, can not explain observed patterns of complex processes, is too easily dismissive of alternative selectionist models, underestimates the creative force of complexity as such, and – if seen as a major evolutionary mechanism for all organisms – could stifle further thought regarding the evolution of highly complex biological processes.
Intrinsic autotrophic biomass yield and productivity in algae: Modeling spectral and mixing‐rate dependence
Authors: Holland Alexandra D. , Wheeler Dean R.
Published: March 2011

For non‐inhibitory irradiances, the rate of algal biomass synthesis was modeled as the product of the algal autotrophic yield ΦDW and the flux of photons absorbed by the culture, as described using Beer‐Lambert law. As a contrast to earlier attempts, the use of scatter‐corrected extinction coefficients enabled the validation of such approach, which bypasses determination of photosynthesis‐irradiance (PI) kinetic parameters. The broad misconception that PI curves, or the equivalent use of specific growth rate expressions independent of the biomass concentration, can be extended to adequately model biomass production under light‐limitation is addressed. For inhibitory irradiances, a proposed mechanistic model, based on the photosynthetic units (PSU) concept, allows one to estimate a target speed νT across the photic zone in order to limit the flux of photons per cell to levels averting significant reductions in ΦDW. These modeled target speeds, on the order of 5–20 m s(1 for high outdoor irradiances, call for fundamental changes in reactor design to optimize biomass productivity. The presented analysis enables a straightforward bioreactor parameterization, which, in‐turn, guides the establishment of conditions ensuring maximum productivity and complete nutrients consumption. Additionally, solar and fluorescent lighting spectra were used to calculate energy to photon‐counts conversion factors.
Nitrogen starvation strategies and photobioreactor design for enhancing lipid content and lipid production of a newly isolated microalga Chlorella vulgaris ESP‐31: Implications for biofuels
Authors: Yeh Kuei‐Ling , Chang Jo‐Shu
Published: March 2011

Microalgae are recognized for serving as a sustainable source for biodiesel production. This study investigated the effect of nitrogen starvation strategies and photobioreactor design on the performance of lipid production and of CO2 fixation of an indigenous microalga Chlorella vulgaris ESP‐31. Comparison of single‐stage and two‐stage nitrogen starvation strategies shows that single‐stage cultivation on basal medium with low initial nitrogen source concentration (i.e., 0.313 g/L KNO3) was the most effective approach to enhance microalgal lipid production, attaining a lipid productivity of 78 mg/L/d and a lipid content of 55.9%. The lipid productivity of C. vulgaris ESP‐31 was further upgraded to 132.4 mg/L/d when it was grown in a vertical tubular photobioreactor with a high surface to volume ratio of 109.3 m2/m3. The high lipid productivity was also accompanied by fixation of 6.36 g CO2 during the 10‐day photoautotrophic growth with a CO2 fixation rate of 430 mg/L/d. Analysis of fatty acid composition of the microalgal lipid indicates that over 65% of fatty acids in the microalgal lipid are saturated [i.e., palmitic acid (C16:0) and stearic acid (C18:0)] and monounsaturated [i.e., oleic acid (C18:1)]. This lipid quality is suitable for biodiesel production.
Integration of biomolecules and nanomaterials: Towards highly selective and sensitive biosensors
Authors: Hyun Seok  , Park Tai Hyun
Published: March 2011

Significant efforts have been made toward the development of high‐performance biosensors for various applications. Advances in nanotechnology have resulted in the development of highly sensitive electrochemical sensing devices. It is believed that highly sensitive and selective biosensors can be realized through the integration of biomolecules and nanomaterial‐based sensor platforms. Numerous articles have described combining biomolecules as recognition elements with nanotechnology for the development of biosensors with enhanced selectivity and sensitivity. Recent advances in the development of biosensors through the integration of biomolecules with nanotechnology are reviewed in this article.
Mitochondria induce oxidative stress, generation of reactive oxygen species and redox state unbalance of the eye lens leading to human cataract formation: disruption of redox lens organization by phospholipid hydroperoxides as a common basis for cataract disease
Authors: Babizhayev Mark A.
Published: March 2011

The aging eye appears to be at considerable risk from oxidative stress. Lipid peroxidation (LPO) is one of the mechanisms of cataractogenesis, initiated by enhanced promotion of oxygen free radicals in the eye fluids and tissues and impaired enzymatic and non‐enzymatic antioxidant defenses of the crystalline lens. The present study proposes that mitochondria are one of the major sources of reactive oxygen species (ROS) in mammalian and human lens epithelial cells and that therapies that protect mitochondria in lens epithelial cells from damage and reduce damaging ROS generation may potentially ameliorate the effects of free radical‐induced oxidation that occur in aging ocular tissues and in human cataract diseases. It has been found that rather than complete removal of oxidants by the high levels of protective enzyme activities such as superoxide dismutase (SOD), catalase, lipid peroxidases in transparent lenses, the lens conversely, possess a balance between peroxidants and antioxidants in a way that normal lens tends to generate oxidants diffusing from lenticular tissues, shifting the redox status of the lens to become more oxidizing during both morphogenesis and aging. Release of the oxidants (O, H2O2, OH., and lipid hydroperoxides) by the intact lenses in the absence of respiratory inhibitors indicates that these metabolites are normal physiological products inversely related to the lens life‐span potential (maturity of cataract) generated through the metal‐ion catalyzed redox‐coupled pro‐oxidant activation of the lens reductants (ascorbic acid, glutathione). The membrane‐bound phospholipid (PL) hydroperoxides escape detoxification by the lens enzymatic reduction. The lens cells containing these species would be vulnerable to peroxidative attack which trigger the PL hydroperoxide‐dependent chain propagation of LPO and other damages in membrane (lipid and protein alterations). The increased concentrations of primary LPO products (diene conjugates, lipid hydroperoxides) and end fluorescent LPO products were detected in the lipid moiety of the aqueous humor samples obtained from patients with cataract as compared to normal donors. Since LPO is clinically important in many of the pathological effects and aging, new therapeutic modalities, such as patented N‐acetylcarnosine prodrug lubricant eye drops, should treat the incessant infliction of damage to the lens cells and biomolecules by reactive lipid peroxides and oxygen species and “refashion” the affected lens membranes in the lack of important metabolic detoxification of PL peroxides. Combined in ophthalmic formulations with N‐acetylcarnosine, mitochondria‐targeted antioxidants are promising to become investigated as a potential tool for treating a number of ROS‐related ocular diseases, including human cataracts. Copyright © 2011 John Wiley & Sons, Ltd.
Low‐temperature CH4 Catalytic Combustion over Pd Catalyst Supported on Co3O4 Nanocrystals with Well‐Defined Crystal Planes
Authors: Hu Linhua , Peng Qing , Li Yadong
Published: March 2011

We report a novel strategy to prepare supported Pd catalysts for low‐temperature methane combustion. The structure–property relationship of the catalysts was investigated by tuning the shape and crystal planes of supporting Co3O4 nanocrystals. Pd/Co3O4 nanosheets are more reactive than Pd/Co3O4 nanobelts and nanocubes with the same Pd loading. The strong surface interaction between the Co3O4 unit cell and the PdO unit cell on {112} crystal plane of Pd/Co3O4 nanosheets has been analyzed by using high resolution transmission electron microscopy and temperature programmed reduction experiments.
Self‐Assembled 3D Flowerlike Hierarchical Fe3O4@Bi2O3 Core–Shell Architectures and Their Enhanced Photocatalytic Activity under Visible Light
Authors: Wang Yang , Li Shikuo , Xing Xianran , Huang Fangzhi , Shen Yuhua , Xie Anjian , Wang Xiufang , Zhang Jian
Published: March 2011

Three‐dimensional (3D) flowerlike hierarchical Fe3O4@Bi2O3 core–shell architectures were synthesized by a simple and direct solvothermal route without any linker shell. The results indicated that the size of the 3D flowerlike hierarchical microspheres was about 420 nm and the shell was composed of several nanosheets with a thickness of 4–10 nm and a width of 100–140 nm. The saturation magnetization of the superparamagnetic composite microspheres was about 41 emu g−1 at room temperature. Moreover, the Fe3O4@Bi2O3 composite microspheres showed much higher (7–10 times) photocatalytic activity than commercial Bi2O3 particles under visible‐light irradiation. The possible formation mechanism was proposed for Ostwald ripening and the self‐assembled process. This novel composite material may have potential applications in water treatment, degradation of dye pollutants, and environmental cleaning, for example.
Conformations of Spermine in Adenosine Triphosphate Complex: The Structural Basis for Weak Bimolecular Interactions of Major Cellular Electrolytes
Authors: Maruyoshi Keisuke , Yamaguchi Toshiyuki , Demura Tetsuo , Matsumori Nobuaki , Oishi Tohru , Murata Michio
Published: March 2011

Selectively 2H‐ and 13C‐labeled spermines (SPM) were efficiently synthesized and analyzed by NMR spectroscopy to determine the spin–spin coupling constants for six conformationally relevant bonds. SPM that is composed of three alkyl moieties, a butanylene, and two propanylene chains undergoes a conformational change when interacting with multivalent anions (e.g., adenosine triphosphate (ATP), ATP–Mg2+, and tripolyphosphate). Upon interaction with ATP, the CC bonds, which affect the distance between the neighboring pairs of ammonium groups (i.e., N1/N5 and N5/N5′), increase the population of gauche rotamers by 17–20 % relative to those in the 4 HCl salt of SPM. However, the trend in increments of the gauche conformers for the SPM–ATP complex profoundly differs from that of the spermidine (SPD)–ATP complex. This implies that SPM may preferentially recognize the adenyl group of ATP rather than the tripolyphosphate moiety. This may account for the higher affinity of SPM to ATP–Mg2+ than with that of SPD, which chiefly interacts with β‐ and γ‐phosphates and is easily replaced by Mg2+. These results may provide a clue for the further understanding of the structural basis of polyamine biological functions.
A Novel and Convenient Synthesis of Benzonitriles: Electrophilic Cyanation of Aryl and Heteroaryl Bromides
Authors: Anbarasan Pazhamalai , Neumann Helfried , Beller Matthias
Published: March 2011

N‐Cyano‐N‐phenyl‐p‐methylbenzenesulfonamide has been used as a more benign electrophilic cyanation reagent for the synthesis of various benzonitriles from (hetero)aryl bromides via formation of Grignard reagents. Electronically different and sterically demanding aryl bromides including functionalized substrates and heteroaryl bromides are successfully cyanated in good to excellent yields. The efficiency of the present methodology is shown by the expeditious syntheses of interesting pharmaceutical intermediates. Notably, chemoselective monocyanation of dibromoarenes is also achieved.
Synthesis, Structure, and Reactivity of a Pyridine‐Stabilized Germanone
Authors: Yao Shenglai , Xiong Yun , Wang Wenyuan , Driess Matthias
Published: March 2011

The first isolable pyridine‐stabilized germanone has been prepared and its reactivity toward trimethylaluminum has been investigated. The germanone adduct results from a stepwise conversion that starts from 4‐dimethylaminopyridine (DMAP) and the ylide‐like N‐heterocyclic germylene LGe: (L=CH{(CCH2)(CMe)[N(aryl)]2}, aryl=2,6‐iPr2C6H3) (1) at room temperature, and gives the corresponding germylene–pyridine adduct L(DMAP)Ge: (2) in 91 % yield. The latter reacts with N2O at room temperature to form the desired germanone complex L(DMAP)GeO (3) in 73 % yield. The GeO distance of 1.646(2) Å in 3 is the shortest hitherto reported for a GeO species. The reaction of 3 with trimethylaluminum leads solely to the addition product LGe(Me)O[Al(DMAP)Me2] (4). The latter results from insertion of the GeO subunit into an AlMe bond of AlMe3 and concomitant migration of the DMAP ligand from germanium to the aluminum atom. Compounds 2–4 have been fully characterized by analytical and spectroscopic methods. Their molecular structures have been established by single‐crystal X‐ray crystallographic analysis.
Stereoselective degradation of diclofop‐methyl during alcohol fermentation process
Authors: Lu Yuele , Diao Jinling , Gu Xu , Zhang Yanfeng , Xu Peng , Wang Peng , Zhou Zhiqiang
Published: March 2011

Stereoselective degradation of Diclofop‐methyl (DM) has been found in alcohol fermentation of grape must and sucrose solution with dry yeast. A method was developed for separation and determination the two enantiomers of DM during the fermentation process by high‐performance liquid chromatography based on cellulose tri‐(3,5‐dimethylphenyl‐carbamate) chiral stationary phase. The results showed that the enantiomers of DM degraded following the first‐order kinetics in the sucrose solution and the degradation of DM enantiomers in grape must were biphasic (slow‐fast‐slow process). In the sucrose solution, half lives of (+)‐(R)‐DM and (−)‐(S)‐DM were calculated to be 8.5 h and 3.1 h, respectively. In the grape must, half life of (+)‐(R)‐DM was calculated to be 41.7 h while (−)‐(S)‐DM was 16.0 h. The result was that (−)‐(S)‐enantiomer degraded faster than the (+)‐(R)‐enantiomer in both alcohol fermentation. The results also showed that the differences of the enantioselective degradation of DM depended on the fermentation matrix. DM was configurationally stable in fermentation, showing no interconversion of (−)‐(S)‐ to (+)‐(R)‐ enantiomer, and vice‐versa. Chirality, 2011. © 2011 Wiley‐Liss, Inc.
Stochastic Modeling of Particle Formation in Fluidized Beds
Authors: Dernedde Mathias , Peglow Mirko , Tsotsas Evangelos
Published: March 2011

Die vorliegende Studie präsentiert die Anwendung einer stochastischen Lösungsmethode zur Populationsbilanzierung in Wirbelschicht‐Sprühagglomerationsprozessen. Die Monte‐Carlo‐Methode wird dabei als spezielles Lösungsverfahren genutzt, um eine diskrete Partikelprobe unter dem Einfluss von wirkenden Mikroprozessen im realen Prozess zu entwickeln. Besonderes Augenmerk wird auf die beispielhafte Beschreibung eines ausgewählten Mikroprozesses gelegt: der Vortrocknung von Tropfen zwischen Düse und Wirbelschicht.
Racial disparities and socioeconomic status in men diagnosed with testicular germ cell tumors
Authors: Sun Maxine , Abdollah Firas , Liberman Daniel , Abdo Al'a , Thuret Rodolphe , Tian Zhe , Shariat Shahrokh F. , Montorsi Francesco , Perrotte Paul , Karakiewicz Pierre I.
Published: March 2011

BACKGROUND:

Previous reports indicated that African‐American men with testicular germ cell tumors (TGCTs) have more aggressive tumor characteristics and less favorable outcomes than other men. The authors of this report evaluated the effects of race and socioeconomic status (SES) on stage distribution, overall mortality (OM), and cancer‐specific mortality (CSM) in men with TGCTs.

METHODS:

The Surveillance, Epidemiology, and End Results (SEER) database was used to identify 22,553 men who were diagnosed with TGCTs between 1988 and 2006. Kaplan‐Meier and Cox regression analyses were generated to predict OM and CSM. Covariates of the analyses included race, SES, age, histologic subtype, disease stage, procedure type, SEER registry, and year of diagnosis. The interaction between race and SES also was examined.

RESULTS:

Overall, there were 516 African‐American men, 21,090 Caucasian men, and 947 men of other races. African‐Americans (14.9%) and individuals with low SES (10.7%) had a higher proportion of distant stage disease. CSM and OM rates were significantly higher for African‐American patients and for patients who resided in low SES counties. Multivariate analyses revealed that African‐American men and men with low SES were more likely to die of OM and CSM relative to Caucasian men (P < .001) and men with high SES (P < .001), respectively. The interaction between race and SES was not significant.

CONCLUSIONS:

African‐American race and low SES appeared to predispose men to more advanced disease stages and to higher OM and CSM rates. These observations may warrant race‐specific and/or SES‐specific adjustments in the treatment of TGCT. Cancer 2011;. © 2011 American Cancer Society.