bluuebunny/crossref_metadata_2025_split huggingface dataset:
A study on the heterobinuclear site of Co(salen)/TiO2SiO2 catalysts in the oxidative carbonylation of aniline
Authors: Mei Fu‐Ming , Chen Li‐Juan , Li Guang‐Xing 
Published: November 2009

AbstractTitania‐silica immobilized Co(salen) complexes containing the heterobinuclear site were prepared by the sol–gel method for the catalytic synthesis of methyl N‐phenylcarbamate (MPC) by the oxidative carbonylation of aniline. It was found that the Ti:Si mole ratio had an important effect on the catalytic performance of Co(salen) complexes. When the Ti:Si ratio was 0.1, titania‐silica supported Co(salophen) showed the best catalytic activity. Under the reaction conditions, Co(salophen)/TS‐0.1, 0.5 g, aniline 11 mmol, methanol 25 ml, KI 2.2 mmol, CO:O2 9:1, total pressure 6 MPa, 150 °C, 3 h, the conversion of aniline and the selectivity of MPC were 60.7 and 88.1%, respectively. The XRD studies showed that titania was highly dispersed in the silica matrix. Co(salophen)/TS‐0.1 was reused five times with no significant loss of the activity, and no Co leaching was observed in the reaction. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and reactivity of some diselenasila cycles containing an annelated dicarba‐closo‐dodecaborane(12) unit
Authors: Wrackmeyer Bernd , Klimkina Elena V. , Milius Wolfgang 
Published: November 2009

AbstractThe use of 1,2‐diselenolato‐1,2‐dicarba‐closo‐dodecaborane(12) dianions [1,2‐(1,2‐C2B10H10)Se2]2− prepared in situ as the dilithium salt may lead to irreproducible results. This is shown by the straightforward synthesis of silanes using the purified and isolated dianions, in contrast with previous less successful attempts. Thus, the reactions of the dianions with dichlorosilanes afford the five‐membered diselenasila cycles containing the SiMe2 or the SiPh2 units, and with 1,2‐dichloro‐tetramethyldisilane the six‐membered cycle containing the Si2Me4 unit. The latter was studied by X‐ray diffraction, and all products were characterized by multinuclear magnetic resonance (1H, 13C, 29Si, 77Se NMR) in solution. Novel isotope effects were detected in 13C and 77Se NMR spectra. Exchange reactions of the five‐ and six‐membered diselanasila cycles with chlorosilanes were studied. Copyright © 2009 John Wiley & Sons, Ltd.
Palladium(II)‐catalyzed catalytic aminocarbonylation and alkoxycarbonylation of terminal alkynes: regioselectivity controlled by the nucleophiles
Authors: Suleiman Rami , Tijani Jimoh , El Ali Bassam 
Published: November 2009

AbstractThe aminocarbonylation and alkoxycarbonylation reactions of terminal alkynes took place smoothly and efficiently using a catalyst system Pd(OAc)2–dppb–p‐TsOHCH3CNCO under relatively mild experimental conditions. The catalytic system was tested and optimized using two different nucleophiles: alcohols and amines. Phenylacetylene (1a) was considered as an alkyne along with diisobutylamine (2b1) and methanol (2c1) as nucleophiles. The results showed significant differences in the conversion of 1a and in the selectivity towards the gem or trans unsaturated esters or amides with these nucleophiles. The effects of the type of palladium catalysts, the type of ligands, the amount of dppb and the solvents were carefully studied. With diisobutylamine (2b1), excellent regioselectivity towards the 2‐acrylamides (gem isomer, 3ab1) was almost always observed, while trans‐α,β‐unsaturated esters 4ac1 was the predominant product with methanol (2c1) as a nucleophile. This remarkable sensitivity in the selectivity of the reaction indicates two different possible mechanistic pathways for these carbonylation reactions. Copyright © 2009 John Wiley & Sons, Ltd.
Evaluation of the Brain Network Organization From EEG Signals: A Preliminary Evidence in Stroke Patient
Authors: De Vico Fallani Fabrizio , Astolfi Laura , Cincotti Febo , Mattia Donatella , la Rocca Daria , Maksuti Elira , Salinari Serenella , Babiloni Fabio , Vegso Balazs , Kozmann Gyorgy , Nagy Zoltan 
Published: November 2009

AbstractSynchronous brain activity in motor cortex in perception or in complex cognitive processing has been the subject of several studies. The advanced analysis of cerebral electro‐physiological activity during the course of planning (PRE) or execution of movement (EXE) in a high temporal resolution could reveal interesting information about the brain functional organization in patients following stroke damage. High‐power (128 channels) electroencephalography registration was carried out on 8 healthy subjects and on a patient with stroke with capsular lacuna in the right hemisphere. For activation of motor cortex, the finger tapping paradigm was used. In this preliminary study, we tested a theoretical graph approach to characterize the task‐related spectral coherence. All of the obtained brain functional networks were analyzed by the connectivity degree, the degree distribution, and efficiency parameters in the Theta, Alpha, Beta, and Gamma bands during the PRE and EXE intervals. All the brain networks were found to hold a regular and ordered topology. However, significant differences (P < 0.01) emerged between the patient with stroke and the control subjects, independently of the neural processes related to the PRE or EXE periods. In the Beta (13–29 Hz) and Gamma (30–40 Hz) bands, the significant (P < 0.01) decrease in global‐ and local‐efficiency in the patient's networks, reflected a lower capacity to integrate communication between distant brain regions and a lower tendency to be modular. This weak organization is principally due to the significant (P < 0.01 Bonferroni corrected) increase in disconnected nodes together with the significant increase in the links in some other crucial vertices. Anat Rec, 292:2023–2031, 2009. © 2009 Wiley‐Liss, Inc.
Ischemic Tolerance: The Mechanisms of Neuroprotective Strategy
Authors: Lehotský Jan , Burda Jozef , DanielisovÁ Viera , Gottlieb Miroslav , Kaplán Peter , Saniová Beata 
Published: November 2009

AbstractThe phenomenon of ischemic tolerance perfectly describes this quote “What does not kill you makes you stronger.” Ischemic pre‐ or postconditioning is actually the strongest known procedure to prevent or reverse neurodegeneration. It works specifically in sensitive vulnerable neuronal populations, which are represented by pyramidal neurons in the hippocampal CA1 region. However, tolerance is effective in other brain cell populations as well. Although, its nomenclature is “ischemic” tolerance, the tolerant phenotype can also be induced by other stimuli that lead to delayed neuronal death (intoxication). Moreover, the recent data have proven that this phenomenon is not limited to application of sublethal stimuli before the lethal stress but reversed arrangement of events, sublethal stress after lethal insult, is rather equally effective. A very important term is called “cross conditioning.” Cross conditioning is the capability of one stressor to induce tolerance against another. So, since pre‐ or post‐conditioners can be used plenty of harmful stimuli, hypo‐ or hyperthermia and some physiological compounds, such as norepinephrine, bradykinin. Delayed neuronal death is the slow development of postischemic neurodegeneration. This allows an opportunity for a great therapeutic window of 2–3 days to reverse the cellular death process. Moreover, it seems that the mechanisms of ischemic tolerance‐delayed postconditioning could be used not only after ischemia but also in some other processes leading to apoptosis. Anat Rec, 292:2002–2012, 2009. © 2009 Wiley‐Liss, Inc.
Toward the Treatments with Neural Stem Cells: Experiences from Amyotrophic Lateral Sclerosis
Authors: Mitrečić Dinko , Gajović Srećko , Pochet Roland 
Published: November 2009

AbstractCommon pathological features of neurodegenerative diseases are progressive dysfunction and neuronal death. In amyotrophic lateral sclerosis (ALS), motor neurons are selectively affected, leading to death because of paralysis. The main therapeutic goal in neurodegenerative diseases is to diminish neural dysfunction and to replace non‐functional cells with the new ones. “Cell‐oriented” treatment strategies include isolation of neural stem cells (NSC), their controlled differentiation, and cellular injections targeting the affected region. Beneficial effects of injected cells result from the combination of cell replacement and secretion of the growth factors. Here, we summarize the current state of isolation and differentiation of NSC, and emphasize the embryo tail bud as a particular region where neuroepithelium differentiates from undifferentiated mesenchymal cells over the course of normal development. The possibility to obtain cells from autologous mesenchyme capable of integrating into affected regions represents a major challenge whose achievement should circumvent the pitfall of the immune reaction against transplanted cells. We also present our own results: when intravenously injected in symptomatic ALS rats, NSC migrated to the motor cortex and continued to differentiate. Thus, we illustrate that the use of NSC in rodent models of ALS may represent a paradigm for other neurodegenerative diseases. Anat Rec, 292:1962–1967, 2009. © 2009 Wiley‐Liss, Inc.
From Birth Till Death: Neurogenesis, Cell Cycle, and Neurodegeneration
Authors: Demir Ozlem , Singh Sheila , Klimaschewski Lars , Aksan Kurnaz Isil 
Published: November 2009

AbstractNeurogenesis in the embryo involves many signaling pathways and transcriptional programs and an elaborate orchestration of cell cycle exit in differentiating precursors. However, while the neurons differentiate into a plethora of different subtypes and different identities, they also presume a highly polar structure with a particular morphology of the cytoskeleton, thereby making it almost impossible for any differentiated cell to re‐enter the cell cycle. It has been observed that dysregulated or forced cell cycle reentry is closely linked to neurodegeneration and apoptosis in neurons, most likely through changes in the neurocytoskeleton. However, proliferative cells still exist within the nervous system, and adult neural stem cells (NSCs) have been identified in the Central Nervous System (CNS) in the past decade, raising a great stir in the neuroscience community. NSCs present a new therapeutic potential, and much effort has since gone into understanding the molecular mechanisms driving differentiation of specific neuronal lineages, such as dopaminergic neurons, for use in regenerative medicine, either through transplanted NSCs or manipulation of existing ones. Nevertheless, differentiation and proliferation are two sides of the same coin, just like tumorigenesis and degeneration. Tumor formation may be regarded as a de‐differentiation of tissues, where cell cycle mechanisms are reactivated in differentiated cell types. It is thus important to understand the molecular mechanisms underlying various brain tumors in this perspective. The recent Cancer Stem Cell (CSC) hypothesis also suggests the presence of Brain Tumor Initiating Cells (BTICs) within a tumor population, although the exact origin of these rare and mostly elusive BTICs are yet to be identified. This review attempts to investigate the correlation of neural stem cells/precursors, mature neurons, BTICs and brain tumors with respect to cell cycle regulation and the impact of cell cycle in neurodegeneration. Anat Rec, 292:1953–1961, 2009. © 2009 Wiley‐Liss, Inc.
In Vivo Morphological Changes in Animal Models of Amyotrophic Lateral Sclerosis and Alzheimer's‐Like Disease: MRI Approach
Authors: Andjus Pavle R. , Bataveljić Danijela , Vanhoutte Greetje , Mitrecic Dinko , Pizzolante Fabrizio , Djogo Nevena , Nicaise Charles , Kengne Fabrice Gankam , Gangitano Carlo , Michetti Fabrizio , van der Linden Annemie , Pochet Roland , Bačić Goran 
Published: November 2009

AbstractMagnetic resonance imaging (MRI) is the only noninvasive technique that provides structural information on both cell loss and metabolic changes. After reviewing all the results obtained in clinical studies, reliable biomarkers in neurological diseases are still lacking. Diffusional MRI, MR spectroscopy, and the assessment of regional atrophy are promising approaches, but they cannot be simultaneously used on a single patient. Thus, for further research progress, reliable animal models are needed. To this aim, we have used the clinical MRI to assess neurodegenerative processes in the hSOD‐1G93A ALS rat model and in the trimethyltin (TMT)‐treated model of Alzheimer's‐like disease. T2‐weighted (T2W) hyperintensive neurodegenerative foci were found in the brainstem of the ALS rat with apparent lateral ventricle dilation (T1W—hypointensity vs. T2W—hyperintensity). Degenerative processes in these areas were also confirmed by confocal images of GFAP‐positive astrogliosis. MRI after i.v.i. of magnetic anti‐CD4 antibodies indicated an accumulation of inflammatory cells near dilated ventricles. TMT‐treated rats also revealed the dilation of lateral ventricles. Expected deterioration in the hippocampus was not observed by clinical MRI, but immunocytochemistry could reveal significant redistribution of macro‐ and microglia in this structure. In both models, Gd‐DTPA contrast revealed a compromised blood brain barrier that may serve as the passage for inflammatory immune cells in the vicinity of dilated lateral ventricles. Moreover, in both models the midbrain region of the dorsal hippocampus was the target of BBB compromise, thus revealing a potentially vulnerable point that can be the primary target of neurodegeneration in the central nervous system. Anat Rec, 292:1882–1892, 2009. © 2009 Wiley‐Liss, Inc.
Synaptotagmins in Neurodegeneration
Authors: Glavan Gordana , Schliebs Reinhard , Živin Marko 
Published: November 2009

AbstractSynaptotagmins (Syts) are transmembrane proteins involved in the regulation of membrane trafficking. Here, we summarize literature data that provide growing evidence that several Syts are involved in the pathophysiological mechanisms of temporal lobe epilepsy and Parkinson's disease, as well as few reports related to brain ischemia and Alzheimer's disease (AD). We also report new data from our laboratories, showing changes of the expression of several Syts in Tg2576 mouse model of AD that may be related to neuroinflammation surrounding the β‐amyloid plaques. Furthermore, we demonstrate N‐methyl‐D‐aspartate receptor‐mediated upregulation of Syt 4 mRNA in a model of excitotoxic striatal lesion induced by unilateral striatal injection of quinolinic acid, associating the upregulation of Syt 4 with mechanisms of excitotoxicity. We propose that phamacological manipulation of Syt expression in animal models of neurodegeneration should be further explored, as it may help to clarify the role of individual Syt isoforms in the regulation of membrane trafficking in neurodegeneration. Anat Rec, 292:1849–1862, 2009. © 2009 Wiley‐Liss, Inc.
Plasticity and Neural Stem Cells in the Enteric Nervous System
Authors: Schäfer Karl‐Herbert , Ginneken Chris Van , Copray Sjef 
Published: November 2009

AbstractThe enteric nervous system (ENS) is a highly organized part of the autonomic nervous system, which innervates the whole gastrointestinal tract by several interconnected neuronal networks. The ENS changes during development and keeps throughout its lifespan a significant capacity to adapt to microenvironmental influences, be it in inflammatory bowel diseases or changing dietary habits. The presence of neural stem cells in the pre‐, postnatal, and adult gut might be one of the prerequisites to adapt to changing conditions. During the last decade, the ENS has increasingly come into the focus of clinical neural stem cell research, forming a considerable pool of neural crest derived stem cells, which could be used for cell therapy of dysganglionosis, that is, diseases based on the deficient or insufficient colonization of the gut by neural crest derived stem cells; in addition, the ENS could be an easily accessible neural stem cell source for cell replacement therapies for neurodegenerative disorders or traumatic lesions of the central nervous system. Anat Rec, 292:1940–1952, 2009. © 2009 Wiley‐Liss, Inc.
Laser‐Induced Autofluorescence Measurements on Brain Tissues
Authors: Pascu Alexandru , Romanitan Mihaela Oana , Delgado Josè‐Maria , Danaila Leon , Pascu Mihail–Lucian 
Published: November 2009

AbstractIt was demonstrated that comparison of the autofluorescence spectra induced with laser radiation in ultraviolet and visible allows the identification of brain tumor tissues and normal tissues as well as the difference between them. The measurements were performed on homogenates to ensure an optimal reproducibility of the results. We conclude that the autofluorescence spectra of the tumor samples are close to those measured for normal tissues, but there are differences between them that allow distinguishing the tumor from the normal tissue. One difference is that for each pair of tumor/normal tissue samples, the peak autofluorescence for the normal tissue is shifted with respect to that for the tumor–typically between 10 and 20 nm; overall autofluorescence intensity is also different for the components of the same pair, the difference being in the range 15%–30%. A parameter that can also be used is the variation of the ratio of some fluorescence intensity peaks between normal and tumor tissue samples. Measurements of this parameter yielded variations ranging between 10% and 40%. Another conclusion of the study is that in vitro experiments show that it is mandatory to use pairs of samples (normal/tumor tissue) taken from the same patient. The results show that, after further experimental in vitro tests, the method may be adapted to real‐time intraoperative conditions by measuring the autofluorescence of the tumor and of the adjacent normal tissue. Anat Rec, 292:2013–2022, 2009. © 2009 Wiley‐Liss, Inc.
Significance and importance: some common misapprehensions about statistics
Authors: Currey John D. , Baxter Paul D. , Pitchford Jonathan W. 
Published: November 2009

AbstractThere are many common misapprehensions about statistics that occur in the literature. We are sure that the three misapprehensions we deal with in this short review are widespread. They concern:

what P values mean;
what an insignificant result means, and what it does not mean; the question of the ‘power’ of a statistical test;
the difference between importance and statistical significance.

We produce no formulae or recipes for dealing with particular situations, instead we concentrate on the commonsense use of simple statistics. We emphasise that if the use of any but the simplest statistics is intended, it is much better to get proper statistical help before starting experiments, rather than afterwards. Copyright © 2009 John Wiley & Sons, Ltd.
Molecular and Supramolecular Structural Studies on Significant Repetitive Sequences of Resilin
Authors: Tamburro Antonio M. , Panariello Simona , Santopietro Valentina , Bracalello Angelo , Bochicchio Brigida , Pepe Antonietta 
Published: November 2009

AbstractResilin is a member of the family of elastomeric proteins and is found in specialised regions of the cuticle of most insects, and provides low stiffness, high strain and efficient energy storage. It is best known for its role in insect flight and the remarkable jumping ability of fleas and spittle bugs. In common with other elastomeric proteins, the recently identified Drosophila melanogaster proresilin shows glycine‐rich repetitive sequences; in particular the N‐ and C‐terminal regions of the protein are dominated by 18 repeats of a 15‐residue sequence (SDTYGAPGGGNGGRP) and eleven repeats of a 13‐residue sequence (GYSGGRPGGQDLG), respectively. We synthesised and analysed the molecular and supramolecular structure of some polypeptides with sequences belonging to the glycine‐rich repeated domain of D. melanogaster resilin. The conformational studies performed by CD, FTIR and NMR spectroscopies pointed to the coexistence of two main conformational features, such as folded β‐turns and (quasi)extended structures (e.g., poly‐L‐proline II conformation) in common with other elastomeric proteins; this suggests an elasticity mechanism for resilin common to other elastomeric proteins. Our data show that also in the case of resilin, repetitive sequences are characterised by autonomous structures almost independent of the remaining parts of the molecule as already extensively found for elastin. From a supramolecular point of view, a great tendency to aggregate in fibrous structures is observed, particularly for the resilin‐ inspired polypeptide (PGGGN)10. This is encouraging for the development of resilin‐based biomaterials for the production of biocompatible medical devices, as well as high performing elastic materials.
Biocatalysis with Thermostable Enzymes: Structure and Properties of a Thermophilic ‘ene’‐Reductase related to Old Yellow Enzyme
Authors: Adalbjörnsson Björn V. , Toogood Helen S. , Fryszkowska Anna , Pudney Christopher R. , Jowitt Thomas A. , Leys David , Scrutton Nigel S. 
Published: November 2009

AbstractWe report the crystal structure of a thermophilic “ene” reductase (TOYE) isolated from Thermoanaerobacter pseudethanolicus E39. The crystal structure reveals a tetrameric enzyme and an active site that is relatively large compared to most other structurally determined and related Old Yellow Enzymes. The enzyme adopts higher order oligomeric states (octamers and dodecamers) in solution, as revealed by sedimentation velocity and multiangle laser light scattering. Bead modelling indicates that the solution structure is consistent with the basic tetrameric structure observed in crystallographic studies and electron microscopy. TOYE is stable at high temperatures (Tm>70 °C) and shows increased resistance to denaturation in water‐miscible organic solvents compared to the mesophilic Old Yellow Enzyme family member, pentaerythritol tetranitrate reductase. TOYE has typical ene‐reductase properties of the Old Yellow Enzyme family. There is currently major interest in using Old Yellow Enzyme family members in the preparative biocatalysis of a number of activated alkenes. The increased stability of TOYE in organic solvents is advantageous for biotransformations in which water‐miscible organic solvents and biphasic reaction conditions are required to both deliver novel substrates and minimize product racemisation.
Entwicklung einer Enzymplattform für die biokatalytische C–C‐Verknüpfung
Authors: Pohl M. , Gocke D. , Müller M. , Kolter G. 
Published: November 2009

AbstractTrotz der wachsenden Beliebtheit von Enzymen als Biokatalysatoren in der organischen Synthese wird deren Anwendung oft dadurch eingeschränkt, dass ein geeignetes Enzym für eine spezielle gewünschte Reaktion nicht schnell genug verfügbar ist. Der Aufbau von Enzymplattformen kann die Suche nach geeigneten Enzymen entscheidend verkürzen. Es wird eine Enzymplattform für die Herstellung chiraler 2‐Hydroxyketone durch C–C‐Verknüpfung von Aldehyden vorgestellt. Chirale 2‐Hydroxyketone sind wertvolle Bausteine für die Herstellung von bioaktiven Molekülen z. B. in der Pharmazie und im Pflanzenschutz. Die Enzymplattform besteht aus diversen natürlichen und gentechnisch veränderten Enzymen. Durch die genaue Kenntnis von Reaktionsmechanismus und der dreidimensionalen Strukturen war es möglich, gezielt Enzymvarianten mit ganz speziellen Eigenschaften herzustellen, die eine große Vielfalt an 2‐Hydroxyketonen zugänglich machen können.