bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reversed phase‐HPLC for rapid determination of polyphenols in flowers of rose species
Authors: Kumar Neeraj , Bhandari Pamita , Singh Bikram , Gupta Ajai P. , Kaul Vijay K. 
Published: January 2008

AbstractA rapid, simple, sensitive, robust, and improved HPLC method was developed and validated for determination of 10 polyphenols, namely gallic acid, catechin, epicatechin, rutin, m‐coumaric acid, quercitrin, myricetin, quercetin, apigenin, and kaempferol in fresh flowers of Rosa bourboniana and R. brunonii and in both fresh flowers and marc (left after industrial distillation of rose oil) of R. damascena. Six polyphenols, gallic acid, rutin, quercitrin, myricetin, quercetin, and kaempferol, were detected and quantified in all extracts. The chromatographic separation of 10 polyphenols was achieved in less than 16 min by RP‐HPLC (Phenomenex, Luna C18 (2) column, 5 μm, 250 mm×4.6 mm) using linear gradient elution of water and acetonitrile (0.02% trifluroacetic acid) with a flow rate of 1 mL/min at λ 280 nm. Standard calibration curves were linear in the range of 0.39–500 μg/mL. Good results were achieved with respect to repeatability (RSD <3%) and recovery (98.6–100.8%). The method was validated for linearity, accuracy, repeatability, LOD, and LOQ.
Headspace single‐drop microextraction of herbal essential oils
Authors: Adam Martin , Dobiáš Petr , Eisner Aleš , Ventura Karel 
Published: January 2008

AbstractA method employing the headspace single‐drop microextraction (HS‐SDME) is presented for the determination of essential oils in dried herbal leaves. By optimising the key experimental parameters, a linear response for the individual target compounds was obtained in the concentration range from LOQ to 4 mg/mL (r2 = 0.9912–0.9998), with LODs from 3.3 up to 20.5 μg per 100 g of dried leaves, and the repeatability within the RSD of 2.1–8.9%. The HS‐SDME‐based procedure, enabling a rapid and simple analysis of essential oils in herbs, was applied to selected real samples (nine essential oils in four different samples) in combination with GC‐FID identification and quantification of the target volatiles.
Dystonia in the Woodhouse Sakati syndrome: A new family and literature review
Authors: Schneider Susanne A. , Bhatia Kailash P. 
Published: January 2008

AbstractWoodhouse Sakati syndrome is a rare autosomal recessive neuroendocrine disorder characterized by the combination of alopecia, hypogonadism, diabetes mellitus, mental retardation, sensory neural deafness and extrapyramidal features. Movement disorders mainly consist of dystonia and chorea of the limbs with onset in adolescence. Facial muscles are usually spared, but dysarthria is common. Pyramidal features and peripheral abnormalities are inconsistent features. Most of the reported families are from the Middle Eastern countries although rarely Caucasian cases have been described. Here we present clinical details of two affected siblings from a new Middle East family and draw attention of movement disorder specialists to this entity. We summarize findings from pervious cases with particular focus on neurological and movement disorder features. © 2007 Movement Disorder Society
Voluntary, spontaneous, and reflex blinking in Parkinson's disease
Authors: Agostino Rocco , Bologna Matteo , Dinapoli Loredana , Gregori Bruno , Fabbrini Giovanni , Accornero Neri , Berardelli Alfredo 
Published: January 2008

AbstractBlinking, a motor act consisting of a closing and an opening eyelid movement, can be performed voluntarily, spontaneously, and reflexly. In this study we investigated the kinematic features of voluntary, spontaneous, and reflex blinking in patients with Parkinson's disease (PD), OFF and ON dopaminergic treatment. Patients were asked to blink voluntarily as fast as possible. Spontaneous blinking was recorded for a minute during which the subjects just relaxed. Reflex blinking was evoked by electrical stimulation on the supraorbital nerve. Eyelid movements were recorded with the SMART analyzer motion system. Patients OFF therapy paused longer than controls during voluntary blinking but not during spontaneous and reflex blinking. The blink rate tended to be lower in patients OFF therapy than in controls and the spontaneous blinking had abnormally low amplitude and peak velocity. Finally, in patients OFF therapy the excitability of the neural circuit mediating the closing phase of the reflex blinking was enhanced. Dopaminergic treatment shortened the pause during voluntary blinking and increased the blink rate. In PD patients the longer pauses between the closing and opening phase in comparison to normal subjects, suggest bradykinesia of voluntary blinking. PD patients also display kinematic abnormalities of spontaneous blinking and changes in the excitability of the closing phase of reflex blinking. © 2007 Movement Disorder Society
Assessment of idiopathic rapid‐eye‐movement sleep behavior disorder by transcranial sonography, olfactory function test, and FP‐CIT‐SPECT
Authors: Unger Marcus M. , Möller Jens C. , Stiasny‐Kolster Karin , Mankel Katharina , Berg Daniela , Walter Uwe , Hoeffken Helmut , Mayer Geert , Oertel Wolfgang H. 
Published: January 2008

AbstractIdiopathic rapid‐eye‐movement (REM) sleep behavior disorder (iRBD) has been suggested to be a risk factor for subsequent development of neurodegenerative disorders, especially Parkinson's disease (PD) and other α‐synucleinopathies. At present, it is not possible to predict whether or not an iRBD patient will eventually develop PD. Here, we report 5 iRBD patients who underwent a test battery comprising a neurological examination (including UPDRS rating), mini mental state examination testing, transcranial sonography, olfactory function testing, and presynaptic dopamine transporter imaging with FP‐CIT‐SPECT. Our preliminary data show the diverse pattern of individual combinations of pathological findings when a multimodal assessment approach is applied in this patient group. Large‐size longitudinal studies in iRBD patients are required to evaluate the usefulness of diagnostic tests to identify the subgroup of iRBD patients that is prone to develop PD. © 2007 Movement Disorder Society
Structure–function relationship of inhibitory Smads: Structural flexibility contributes to functional divergence
Authors: Hariharan Ramkumar , Pillai M. Radhakrishna 
Published: January 2008

AbstractSmads are a small family of eukaryotic transcription regulators that play key roles in the transforming growth factor‐beta signaling cascade. Smad6 and Smad7, the inhibitory or I‐Smads, inhibit signaling downstream of TGF‐beta type I receptors, thereby acting as negative regulators of signaling mediated by TGF‐beta superfamily of ligands. Smad6 is known to specifically inhibit BMP type I receptor mediated signaling, while Smad7 is a more general inhibitor, able to block signaling mediated by a set of related TGF‐beta type I receptors, including type I receptors for BMP and TGF‐beta/Activin. In this study we have sought to understand the structural basis for this functional divergence of I‐Smads. We have created homology‐based models for the MH1 and MH2 domains of the two I‐Smads and have carried out detailed molecular dynamics (MD) simulations of these proteins in explicit solvent to investigate the flexibility of the domains. The molecular models show that the I‐Smads have lost many of the secondary structural elements found in the R‐Smads, giving rise to longer loops in the tertiary structure of Smad6 and Smad7. Detailed analysis of the structural models and the MD trajectories clearly reveal that compared to Smad6, Smad7 has a more flexible overall folding, marked by the presence of highly flexible amino acid residues in functionally important regions of the protein. Interestingly, three of these residues—Phe411, Lys401, and Cys406, map to L3 loop of Smad7 MH2 domain, which is a critical structural determinant in Smad–type I receptor interactions. The increased structural flexibility of Smad7, arising out of longer, more flexible loops in its MH2 domain, might enable Smad7 to interact with a set of related yet structurally diverse type I receptors. Taken together with experimental evidence published in recent literature that hint at structural factors underlying the generic nature of inhibition by Smad7, our results strongly suggest that structural flexibility could be a prime contributor to the functional differences between Smad6 and Smad7. Additionally, we have been able to use the Smad7 structural model to successfully rationalize the results of in vitro site‐specific mutagenesis experiments in published literature. This also provides biological validation for our model. Apart from this, analysis of the MH1 molcular model of Smad6 delineates a basic patch on the surface of the domain that might take part in nonspecific DNA binding by Smad6. This finding is consistent with earlier experimental data and is relevant since the characteristic beta‐hairpin DNA binding element of R‐Smads is completely absent in the I‐Smads. Finally, the molecular models described here can serve to guide future biochemical and genetic studies on I‐Smads. Proteins 2008. © 2008 Wiley‐Liss, Inc.
In silico study of the human rhodopsin and meta rhodopsin II/S‐arrestin complexes: Impact of single point mutations related to retina degenerative diseases
Authors: Mokarzel‐Falcón Leonardo , Padrón‐García Juan Alexander , Carrasco‐Velar Ramón , Berry Colin , Montero‐Cabrera Luis A. 
Published: January 2008

AbstractWe propose two models of the human S‐arrestin/rhodopsin complex in the inactive dark adapted rhodopsin and meta rhodopsin II form, obtained by homology modeling and knowledge based docking. First, a homology model for the human S‐arrestin was built and validated by molecular dynamics, showing an average root mean square deviation difference from the pattern behavior of 0.76 Å. Then, combining the human S‐arrestin model and the modeled structure of the two human rhodopsin forms, we propose two models of interaction for the human S‐arrestin/rhodopsin complex. The models involve two S‐arrestin regions related to the N domain (residues 68–78; 170–182) and a third constituent of the C domain (248–253), with the rhodopsin C terminus (330–348). Of the 22 single point mutations related to retinitis pigmentosa and congenital night blindness located in the cytoplasmatic portion of rhodopsin or in S‐arrestin, our models locate 16 in the interaction region and relate two others to possible dimer formation. Our calculations also predict that the light activated complex is more stable than the dark adapted rhodopsin and, therefore, of higher affinity to S‐arrestin. Proteins 2008. © 2008 Wiley‐Liss, Inc.
X‐ray crystal structure of the B component of Hemolysin BL from Bacillus cereus
Authors: Madegowda Mahendra , Eswaramoorthy Subramaniam , Burley Stephen K. , Swaminathan Subramanyam 
Published: January 2008

AbstractBacillus cereus Hemolysin BL enterotoxin, a ternary complex of three proteins, is the causative agent of food poisoning and requires all three components for virulence. The X‐ray structure of the binding domain of HBL suggests that it may form a pore similar to other soluble channel forming proteins. A putative pathway of pore formation is discussed. Proteins 2008; 71:534–540. Published 2007 Wiley‐Liss, Inc.
The failure of pronatalism in developed states ‘with cultural–ethnic hegemony’: the Israeli lesson
Authors: Winckler O. 
Published: January 2008

AbstractDuring the past two decades, the ‘hot’ demographic issue in the developed states ‘with cultural–ethnic hegemony’ changed radically – from a focus on ‘global demographic pressure’, namely, the ‘Malthusian syndrome’ of rapid population growth in the developing countries, to the ethno‐religious composition of their own populations. The solution adopted by many of these countries to tackle the twin demographic challenges of population ageing and the changing dependency ratio was the implementation of pronatalist policies which aimed at reducing their dependence upon labour immigration. This article examines the efficiency of these pronatalist policies through the Israeli case. The core questions of the article are: Has the Israeli pronatalist policy achieved its basic aims? What influence did the Israeli natalist policy and the child allowance structure have on the fertility patterns of the Israeli‐Arabs? What can be learned from the Israeli experience regarding the efficiency of these pronatalist policies in developed states? The major lesson from the Israeli experience is that, to a large extent, these pronatalist polices failed. The fertility rate of the Jewish middle class, the Christian‐Arabs and the Druze steadily declined, while that of the Israeli‐Muslims, although lower since the 1960s, is still twice that of the Jewish middle class. One can find a similar situation in all of the developed states ‘with cultural–ethnic hegemony.’ Thus, the inescapable conclusion is that in democratic‐developed societies, in which women enjoy equity in every respect, fertility rates will eventually decline to below replacement‐level regardless of pronatalist financial benefits. Consequently, the process of the developed states ‘with cultural–ethnic hegemony’ becoming developed states ‘without cultural–ethnic hegemony’ is irreversible due to the constant need for massive labour immigration. In the case of Israel, at the dawn of the twenty‐first century, there are high fertility rates in only two communities – the Ultra‐Orthodox Jews and the Muslims – paradoxically the two ‘non‐Zionist’ communities. Copyright © 2008 John Wiley & Sons, Ltd.
Kinetics of Cinnamoyl Glycerol Formation
Authors: Holser Ronald A. 
Published: January 2008

AbstractThe esterifications of glycerol with cinnamic acid, 2‐methoxy cinnamic acid, and 4‐methoxy cinnamic acid were investigated in batch reactions. Conversions of over 50% were achieved for cinnamic acid and 4‐methoxy cinnamic acid within 8 h. After 24 h, conversions of over 80% were obtained for cinnamic acid and 4‐methoxy cinnamic acid. Conversions of 33 and 40% were observed for 2‐methoxy cinnamic acid after 8 and 24 h, respectively. These reactions were modeled by a system of sequential first‐order rate expressions. Kinetic parameters were estimated from experimental data fit to the model equations.
Tense over time: testing the Agreement/Tense Omission Model as an account of the pattern of tense-marking provision in early child English
Authors: PINE JULIAN M. , CONTI-RAMSDEN GINA , JOSEPH KATE L. , LIEVEN ELENA V. M. , SERRATRICE LUDOVICA 
Published: January 2008

ABSTRACTThe Agreement/Tense Omission Model (ATOM) predicts that English-speaking children will show similar patterns of provision across different tense-marking morphemes (Rice, Wexler & Hershberger, 1998). The aim of the present study was to test this prediction by examining provision rates for third person singular present tense and first and third person singular forms of copula BE and auxiliary BE in longitudinal data from eleven English-speaking children between the ages of 1 ; 10 and 3 ; 0. The results show, first, that there were systematic differences in the provision rates of the different morphemes; second, that there were systematic differences in the rate at which all of the three morphemes were provided with pronominal and lexical subjects; and, third, that there were systematic differences in the rate at which copula BE and auxiliary BE were provided with the third person singular pronominal subjects It and He and the first person singular subject pronoun I. These results replicate those of Wilson (2003), while controlling for some possible objections to Wilson's analysis. They thus provide further evidence against the generativist view that children's rates of provision of different tense-marking morphemes are determined by a single underlying factor, and are consistent with the constructivist view that children's rates of provision reflect the gradual accumulation of knowledge about tense marking, with much of children's early knowledge being embedded in lexically specific constructions.
PHOTOPROCESSES IN THE ORGANIC SOLID STATE*
Authors: Hochstrasser Robin M. 
Published: January 2008

Summary The various known photo‐relaxation phenomena in organic crystals are reviewed. The discussion is confined to molecular crystals, and aggregates of organic molecules, in which the low‐lying excited electronic states are either πpgr;*, nπ*, or electron‐transfer type. The pathways for excitation in isolated molecules with these types of electronic states are compared with the corresponding process in solids.Particular emphasis is placed on the possible roles of intersystem crossing, triplet‐triplet energy transfer and annihilation in solid state photochemistry. Free and localized excitons, energy migration between impurity traps, and some aspects of photoconduction in organic materials are discussed.
MECHANISMS AND RATES OF RADIATIONLESS ENERGY TRANSFER
Authors: BENNETT R. O. , KELLOGG R. E. 
Published: January 2008

Abstract— Radiationless energy transfer between large molecules has been studied in samples in which a coulombic interaction can be expected to dominate other processes. Measurement of the effect of energy transfer on the lifetime of the donor yields information on the distance dependence of the interaction. The “Forster” formulation of energy transfer due to a coulombic dipole‐dipole interaction has been found to describe accurately the results of both singlet‐singlet and triplet‐singlet transfer. In the latter case, the experimental data are sufficiently precise to be analyzed in a manner suggested by Inokuti and Hirayama, leading to the conclusion that a pure dipole–dipole interaction induces the transfer.RESUMENSe ha estudiado la transferencia no radiativa de energía de moleculas grandes en sistemas en los que la interacción electrostática domina otros procesos. La medición del efecto de la transferencia de energía en la vida media del donor da información sobre la dependencia de distancia de la interacción. La teoria de Förster para la transferencia de energía debida a interacciones electrostaticas dipolo–dipolo se encontró que describe con gran exactitud los resultados obtenidos en el caso de transferencia singulete‐singulete y triplete‐singulete, en este último los datos experimentales son suficientemente precisos como para ser analizados mediante el procedimiento surgerido por Inokuti y Hirayama, Ilevando a la conclusión de que la interacción dipolo–dipolo induce transferencia de energía.
STUDIES ON MUTAGENESIS INDUCED IN VITRO*
Authors: GROSSMAN LAWRENCE 
Published: January 2008

Abstract— The effective reducción of cytosine, whether in polymer form as a template or in monomer form as a substrate, is recognized in the RN A polymerase system as uracil or thymine. reducción can be brought about by photohydration to form cytosine hydrate, reaction with hydroxylamine to form a 5,6‐reduced monoadduct, or by direct chemical reduction.A novel tautomeric intermediate is postulated which has permitted the assay of cytosine hydrates in native and denatured DNA.It is suggested that the most probable u.v. photoproduct responsible for the mutagenesis of DNA is the cytosine hydrate.Similar modification of uracil or thymine results in loss of recognition at both polymer and monomer levels. Reiteration is observed when polyuridylic acid is either chemically reduced or irradiated with u.v.RESUMENLa reducción efectiva de la citosina en forma de polímero, como “template” o en forma de monómero como sustrato, puede reconocerse en el sistema RNA polimerasa como uracilo o timina. La reducción puede ocurrir por fotohidratación para formar hidrato de citosina puede reaccionar con hidroxilamina, o puede sufrir una reducción química directa. Se postula un nuevo intermediario que ha permitido ensayar hidratos de la citosina en DNA nativo y desnaturalizado. Se sugiere que el fotoproducto más probable responsable por esta mutagénesis del DNA es el hidrato de citosina. Modificaciones similares del uracilo o la timina resulta de una pérdida de reconocimiento a nivel de polimero o monomero.
Conservation of Genetic Alterations in Recurrent Melanoma Supports the Melanoma Stem Cell Hypothesis
Authors: Sabatino Marianna , Zhao Yingdong , Voiculescu Sonia , Monaco Alessandro , Robbins Paul , Karai Laszlo , Nickoloff Brian J. , Maio Michele , Selleri Silvia , Marincola Francesco M. , Wang Ena 
Published: January 2008

AbstractIt is generally accepted that human cancers derive from a mutated single cell. However, the genetic steps characterizing various stages of progression remain unclear. Studying a unique case of metastatic melanoma, we observed that cell lines derived from metachronous metastases arising over a decade retained a central core of genetic stability in spite of divergent phenotypes. In the present study, we expanded our previous observations comparing these autologous cell lines of clonal derivation with allogeneic ones and correlated array comparative genomic hybridization (aCGH) with gene expression profiling to determine their relative contribution to the dynamics of disease progression. aCGH and gene expression profiling were performed on autologous cell lines and allogeneic melanoma cell lines originating from other patients. A striking correlation existed between total extent of genetic imbalances, global transcriptional patterns, and cellular phenotypes. They did not follow a strict temporal progression but stemmed independently at various time points from a central core of genetic stability best explained according to the cancer stem cell hypothesis. Although their contribution was intertwined, genomic imbalances detectable by aCGH contributed only 25% of the transcriptional traits determining autologous tumor distinctiveness. Our study provides important insights about the dynamics of cancer progression and supports the development of targeted anticancer therapies aimed against stable genetic factors that are maintained throughout the end stage of disease. [Cancer Res 2008;68(1):122–31]
Is B-Raf a Good Therapeutic Target for Melanoma and Other Malignancies?
Authors: Madhunapantula SubbaRao V. , Robertson Gavin P. 
Published: January 2008

Abstract
The RAF family members, A-Raf, B-Raf, and C-Raf (or Raf-1), are intermediate molecules in the mitogen-activated protein (MAP) kinase [Ras/Raf/MAP kinase/extracellular signal–regulated kinase (Erk) kinase (MEK)/Erk] pathway, which relays extracellular signals from the cell membrane to the nucleus via a cascade of phosphorylation events ultimately promoting cancer development. This pathway is activated by mutation in ∼7% of all human cancers. B-Raf is one of the proteins frequently mutated to an active form during tumor development. Therefore, B-Raf is an attractive cancer target but lack of clinical efficacy using agents targeting this protein has raised serious doubts about its therapeutic utility. Design of more effective B-Raf inhibitory agents, targeting other members of the signaling cascade for greater clinical efficacy or inhibiting B-Raf in combination with other targets, is being evaluated to resolve these perplexing issues. Here, we discuss recent progress, using preclinical models and clinical studies, to resolve the controversy of whether B-Raf would be a good therapeutic target for melanoma and other malignancies. [Cancer Res 2008;68(1):5–8]