bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enantioselective Dehydrogenation of Alkan‐2‐ols by Gaseous (BINOLate)Ni+
Authors: Novara Francesca R. , Schwarz Helmut , Schröder Detlef 
Published: December 2007

AbstractElectrospray ionization of methanolic solutions of nickel(II) nitrate, 1,1′‐binaphthalene‐2,2′‐diol (BINOL), and secondary alcohols (ROH) inter alia affords monocationic complexes of the type [(BINOLate)Ni(ROH)]+, where BINOLate stands for singly deprotonated BINOL. Upon collision‐induced dissociation (CID), the mass‐selected ions undergo competing fragmentations involving loss of the alcohol ligand and expulsion of the corresponding carbonyl compound. The latter reaction leads to the hydride complex [(BINOL)Ni(H)]+ and can thus be regarded as the reversal of the reduction of ketones with metal hydrides. The possibility of the occurrence of enantioselective gas‐phase reactions is probed for combinations of chiral BINOLate ligands with chiral alkan‐2‐ols. Whereas aliphatic alkan‐2‐ols do not show pronounced chiral effects, enantioselective bond activation is observed for 1‐phenylethanol, indicating an interaction of the aromatic ring of the alkanol with the positively charged metal center.
Synthesis of Spiropyrimidodiazepines and Spirodiazepinopurines by Tandem Nitroso‐ene/Diels–Alder Reactions
Authors: Zhang Fang‐Li , Vasella Andrea 
Published: December 2007

AbstractNew spirocyclic heterocycles 8, 16, 19/20, 25, 27, and 30 derived from pyrimido[4,5‐b][1,4]diazepin]‐8′(9′H)‐one were synthesised by a tandem nitroso‐ene/Diels–Alder reaction of 4‐(alkenoylamino)‐5‐nitrosopyrimides. The crystal structure of 16 was established by X‐ray analysis. It is characterised by four pairs of intermolecular H‐bonds linking every two molecules in the unit cell. Sequential imine reduction and intramolecular condensation of the C(4′)‐(acylamino)‐pyrimido[4,5‐b][1,4]diazepines 27 and 30 led to the [1,4]diazepino[1,2,3‐gh]purines 28/29 and 31, respectively.
Thermolysis of Imidates: A New Method for the Generation of Carbonyl Ylides
Authors: Nikolaev Vsevolod V. , Linden Anthony , Heimgartner Heinz 
Published: December 2007

AbstractThermolysis of dimethyl 2‐[(3‐oxo‐3H‐isoindol‐1‐yl)oxy]malonate (8) promotes a [1,4]‐H shift in the imidic NCOCH fragment of the starting molecule, which leads to a reactive carbonyl ylide. This carbonyl ylide can be trapped by the CN bond of imidates and imines, as well as the CO bond of benzaldehyde. The corresponding cycloadducts 11, 14, and 16 are formed regioselectively in good yields (60–95%) and with high stereoselectivity. In the case of 11, the minor cycloadduct in solution undergoes an isomerization to give the more stable stereoisomer. The structures of two cycloadducts, i.e., 11a and 14a, have been established by X‐ray crystallography.
A Novel ‘Domino‐Click Approach’ to Unsymmetrical Bis‐1H‐1,2,3‐triazoles
Authors: Banday Abid H. , Arora Bhupinder S. , Alam Mohammed S. , Kumar Halmuthur M. Sampath 
Published: December 2007

AbstractAryl azides 1 were treated with allenylmagnesium bromide (2) to generate 1,5‐disubstituted butynyl‐1H‐1,2,3‐triazoles 3 in a domino fashion, which upon CuI‐catalyzed 1,3‐dipolar cycloaddition with aryl azides 4 afforded novel bis‐1H‐1,2,3‐triazoles 5 in quantitative yields (Scheme 1 and Table).
ent‐Kaurane Diterpenoids from Isodon japonicus
Authors: Yang Li‐Bin , Huang Sheng‐Xiong , Li Li‐Mei , Zhao Yong , Lei Chun , Xiao Wei‐Lie , Pu Jian‐Xin , Han Quan‐Bin , Sun Han‐Dong 
Published: December 2007

AbstractTwo new 6,7‐seco‐ent‐kaurane diterpenoids, isojaponins A (1) and B (2), together with 18 known ent‐kaurane diterpenoids were isolated from the aerial parts of Isodon japonicus. The structures of the two new compounds were elucidated by extensive 1D‐ and 2D‐NMR spectroscopic methods in combination with MS experiments.
Nine New Sesquiterpenes from Dendrobium nobile
Authors: Zhang Xue , Liu Hong‐Wei , Gao Hao , Han Hui‐Ying , Wang Nai‐Li , Wu Hou‐Ming , Yao Xin‐Sheng , Wang Zhao 
Published: December 2007

AbstractNine new sesquiterpenes, i.e., dendronobilins A–I (1–9), with copacamphane‐type (1), picrotoxane‐type (2–6), muurolene‐type (7), alloaromadendrane‐type (8), and cyclocopacamphane‐type (9) skeletons, were isolated from the 60% EtOH extract of the stems of Dendrobium nobile. Their structures were established as (1R,2R,4S,5S,6S,8S,9R)‐2,8‐dihydroxycopacamphan‐15‐one (1), (2β,3β,4β,5β)‐2,4,11‐trihydroxypicrotoxano‐3(15)‐lactone (2), (2β,3β,5β,9α,11β)‐2,11‐epoxy‐9,11,13‐trihydroxypicrotoxano‐3(15)‐lactone (3), (2β,3β,5β,12R*)‐2,11,13‐trihydroxypicrotoxano‐3(15)‐lactone (4), (2β,3β,5β,12S*)‐2,11,13‐trihydroxypicrotoxano‐3(15)‐lactone (5), (2β,3β,5β,9α)‐9,10‐cyclo‐2,11,13‐trihydroxypicrotoxano‐3(15)‐lactone (6), (9β,10α)‐muurol‐4‐ene‐9,10,11‐triol (7), (10α)‐alloaromadendrane‐10,12,14‐triol (8), and (5β)‐cyclocopacamphane‐5,12,15‐triol (9) on the basis of spectroscopic analysis. The absolute configuration of compound 1 was tentatively assigned as (1R,2R,4S,5S,6S,8S,9R) according to its CD spectrum and the octant rule. Compounds 1 and 4–9 were inactive in our preliminary in vitro immunomodulatory bioassay.
Alkaloids from Fruits of Daphniphyllum oldhamii
Authors: Gan Li‐She , Wang Xiao‐Ning , Fan Cheng‐Qi , Wu Yan , Yue Jian‐Min 
Published: December 2007

AbstractSeventeen Daphniphyllum alkaloids, including two new pentacyclic alkaloids, yuzuric acid (1) and daphnezomic acid (2), and 15 known ones, were isolated from the fruits of Daphniphyllum oldhamii. The structures and configuration of the two new alkaloids were determined on the basis of spectroscopic methods, especially 2D NMR techniques.
A Novel Method for the Synthesis of Substituted Benzochromenes by Ethylenediamine Diacetate‐Catalyzed Cyclizations of Naphthalenols to α,β‐Unsaturated Aldehydes. Concise Synthesis of the Natural Products Lapachenole, Dihydrolapachenole, and Mollugin
Authors: Lee Yong Rok , Kim Yun Mi 
Published: December 2007

AbstractA new synthetic route for biologically interesting benzochromenes was developed starting from naphthalenols and α,β‐unsaturated aldehydes in the presence of ethylenediamine diacetate. This methodology was applied for the total synthesis of the biologically important natural products lapachenole, dihydrolapachenole, and mollugin with a benzochromene moiety.
One‐Pot Synthesis of 4‐(Alkylamino)‐1‐(arylsulfonyl)‐3‐benzoyl‐1,5‐ dihydro‐5‐hydroxy‐5‐phenyl‐2H‐pyrrol‐2‐ones via a Multicomponent Reaction
Authors: Alizadeh Abdolali , Rezvanian Atieh , Zhu Long‐Guan 
Published: December 2007

AbstractAn effective route to novel 4‐(alkylamino)‐1‐(arylsulfonyl)‐3‐benzoyl‐1,5‐dihydro‐5‐hydroxy‐5‐phenyl‐2H‐pyrrol‐2‐ones 10 is described (Scheme 2). This involves the reaction of an enamine, derived from the addition of a primary amine 5 to 1,4‐diphenylbut‐2‐yne‐1,4‐dione, with an arenesulfonyl isocyanate 7. Some of these pyrrolones 10 exhibit a dynamic NMR behavior in solution because of restricted rotation around the CN bond resulting from conjugation of the side‐chain N‐atom with the adjacent α,β‐unsaturated ketone group, and two rotamers are in equilibrium with each other in solution (10 ⇌ 11; Scheme 3). The structures of the highly functionalized compounds 10 were corroborated spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS), by elemental analyses, and, in the case of 10a, by X‐ray crystallography. A plausible mechanism for the reaction is proposed (Scheme 4).
A Guaianolide Sesquiterpene, a Chromenone, and a Flavanone from Ligularia macrophylla
Authors: Wang Qi , Chen Daofeng 
Published: December 2007

AbstractThree new compounds, (5β,9β)‐guaia‐6,10(14)‐dien‐9‐ol (=rel‐(1R,3aS,5R,8aR)‐1,2,3,3a,4,5,6,8a‐octahydro‐1‐methyl‐4‐methylene‐7‐(1‐methylethyl)azulen‐5‐ol; 1), 6‐acetyl‐8‐methoxy‐2,3‐dimethylchromen‐4‐one (=6‐acetyl‐8‐methoxy‐2,3‐dimethyl‐4H‐1‐benzopyran‐4‐one; 2), and (2S)‐3′‐hydroxy‐5′,7‐dimethoxyflavanone (=(2S)‐2,3‐dihydro‐2‐(3‐hydroxy‐5‐methoxyphenyl)‐7‐methoxy‐4H‐1‐benzopyran‐4‐one; 3) were isolated from the roots and rhizomes of Ligularia macrophylla, together with seven known compounds. Their structures and configurations were elucidated by spectroscopic methods, including 2D‐NMR techniques.
Association of catechol‐O‐methyltransferase variants with loudness dependence of auditory evoked potentials
Authors: Juckel Georg , Kawohl Wolfram , Giegling Ina , Mavrogiorgou Paraskevi , Winter Christine , Pogarell Oliver , Mulert Christoph , Hegerl Ulrich , Rujescu Dan 
Published: December 2007

AbstractObjectiveThe loudness dependence of auditory evoked potentials (LDAEP) provides a measure of the central serotonergic activity. As dopamine transporter availabilities also correlate with LDAEP, a dopaminergic influence is probable. The enzyme catechol‐O‐methyltransferase (COMT) is involved in the inactivation of synaptic dopamine. The aim of this study was to investigate the relationship between genetic variants of the COMT gene influencing synaptic dopamine levels and the LDAEP.MethodsRs737865 in intron 1, rs4680 coding for a Val158Met substitution and rs165599 in the 3′ region were investigated in 95 carefully selected healthy subjects of German descent (41 males, 54 females). The LDAEP was calculated as a linear regression slope with stimulus intensity as independent and N1/P2‐amplitude as dependent variables.ResultsSingle marker analysis showed weak associations for two single nucleotide polymorphisms (SNPs) (rs737865: CC vs. T allele carrier; rs4680: G‐allele carrier vs. AA homozygotes). A‐G (rs4680–rs165599) was associated with lower LDAEP scores. Accordingly, haplotype analysis with all SNPs (rs737865–rs4680–rs165599) showed that the T‐A‐G haplotype was associated with lower scores.ConclusionsThese findings support the hypothesis that the LDAEP is also influenced by dopaminergic transmission. However, replications of these very preliminary but potentially important findings in independent samples are needed. Copyright © 2007 John Wiley & Sons, Ltd.
Magnetic resonance imaging‐based detection of glial brain tumors in mice after antiangiogenic treatment
Authors: Claes An , Gambarota Giulio , Hamans Bob , van Tellingen Olaf , Wesseling Pieter , Maass Cathy , Heerschap Arend , Leenders William 
Published: December 2007

AbstractProper delineation of gliomas using contrast‐enhanced magnetic resonance imaging (CE‐MRI) poses a problem in neuro‐oncology. The blood brain barrier (BBB) in areas of diffuse‐infiltrative growth may be intact, precluding extravasation and subsequent MR‐based detection of the contrast agent gadolinium diethylenetriaminepenta‐acetic acid (Gd‐DTPA). Treatment with antiangiogenic compounds may further complicate tumor detection as such compounds can restore the BBB in angiogenic regions. The increasing number of clinical trials with antiangiogenic compounds for treatment of gliomas calls for the development of alternative imaging modalities. Here we investigated whether CE‐MRI using ultrasmall particles of iron oxide (USPIO, Sinerem®) as blood pool contrast agent has additional value for detection of glioma in the brain of nude mice. We compared conventional T1‐weighted Gd‐DTPA‐enhanced MRI to T2*‐weighted USPIO‐enhanced MRI in mice carrying orthotopic U87 glioma, which were either or not treated with the antiangiogenic compound vandetanib (ZD6474, ZACTIMA™). In untreated animals, vessel leakage within the tumor and a relatively high tumor blood volume resulted in good MRI visibility with Gd‐DTPA‐ and USPIO‐enhanced MRI, respectively. Consistent with previous findings, vandetanib treatment restored the BBB in the tumor vasculature, resulting in loss of tumor detectability in Gd‐DTPA MRI. However, due to decreased blood volume, treated tumors could be readily detected in USPIO‐enhanced MRI scans. Our findings suggest that Gd‐DTPA MRI results in overestimation of the effect of antiangiogenic therapy of glioma and that USPIO‐MRI provides an important complementary diagnostic tool to evaluate response to antiangiogenic therapy of these tumors. © 2007 Wiley‐Liss, Inc.
Past, present and future of atomic force microscopy in life sciences and medicine
Authors: Parot Pierre , Dufrêne Yves F. , Hinterdorfer Peter , Le Grimellec Christian , Navajas Daniel , Pellequer Jean‐Luc , Scheuring Simon 
Published: December 2007

AbstractTo introduce this special issue of the Journal of Molecular Recognition dedicated to the applications of atomic force microscopy (AFM) in life sciences, this paper presents a short summary of the history of AFM in biology. Based on contributions from the first international conference of AFM in biological sciences and medicine (AFM BioMed Barcelona, 19–21 April 2007), we present and discuss recent progress made using AFM for studying cells and cellular interactions, probing single molecules, imaging biosurfaces at high resolution and investigating model membranes and their interactions. Future prospects in these different fields are also highlighted. Copyright © 2007 John Wiley & Sons, Ltd.
Structural characterization of pulsed laser deposited poly(methylmethacrylate) thin films
Authors: Fazio B. , Trusso S. , Fazio E. , Neri F. 
Published: December 2007

AbstractCross‐linking content and polymerization degree of poly(methylmethacrylate) PMMA thin films have been investigated by means of Fourier transform infrared and micro‐Raman spectroscopic techniques. The samples were deposited by means of pulsed laser ablation of a PMMA target at room temperature. The laser fluence was varied from 0.5 J/cm2 up to 4 J/cm2. Experimental results show that it is possible to deposit PMMA thin films with a very low monomer content (smaller than 3%) and to modulate the cross‐linking occurrence upon tuning the laser fluence. Moreover, the effect of the post‐deposition thermal treatment on the polymerization degree has been exploited. Then, we estimated the value of the polymerization enthalpy, which is comparable to the value at which the complete conversion of monomers in polymer is reached. Copyright © 2007 John Wiley & Sons, Ltd.
TEM/local excision: Indications, techniques, outcomes, and the future
Authors: Saclarides Theodore J. 
Published: December 2007

AbstractTransanal endoscopic microsurgery (TEM) has emerged as a safe method for excising virtually any rectal adenoma and carefully selected cancers. Extended applications include treatment of extra‐ and supra‐sphincteric fistulae, rectovaginal fistulae, anastomotic strictures, and sinus tracts. The procedure utilizes an air‐tight system, long shafted instruments, high‐quality magnifying optics, and constant carbon dioxide insufflation, all of which facilitate a precise excision and closure with clear margins. Complications are few, most patients can be treated as an outpatient. J. Surg. Oncol. 2007;96:644–650. © 2007 Wiley‐Liss, Inc.
KTP laser and nitinol alloy stents: Are they compatible?
Authors: Young Orla , Kirrane F. , Hughes J.P. , Fenton J.E. 
Published: December 2007

AbstractBackground/ObjectiveNitinol alloy stents are in frequent use in recanalizing malignant airway stenoses. Potassium titanyl phosphate (KTP) is one of the lasers of choice in removal of obstructing airway lesions. There is a paucity of research regarding the safety of these advances working together.Study Design/Materials and MethodsIn vitro study involving direct contact application of KTP laser with nitinol alloy stents under microscope guidance in varying gaseous environments.ResultsStent damage can occur once power settings exceed one watt. Complete stent destruction occurs regardless of gaseous environment at a mere three watts of power.ConclusionsOur results suggest that KTP laser is unsafe to use in the presence of a nitinol alloy stent, regardless of the gaseous environment. Lasers Surg. Med. 39:803–807, 2007. © 2007 Wiley‐Liss, Inc.
Diode laser hair removal around ileo‐colo ostomys is safe, effective and beneficial: A pilot study
Authors: van der Ploeg‐Westerveld Jos , Wagter Jacqueline , van Gemert Martin J.C. , Neumann H.A.M. , Bour H. , Zwart A. 
Published: December 2007

AbstractBackground and ObjectiveHair removal around an ileo‐colo ostomy can cause a number of problems. We compared laser hair removal with mechanical shaving around the ostomy.MethodEleven patients were selected with hairy skin around the ostomy for therapy with an AlGaAs diode laser at 800 nm. Three to four treatments were given with an interval of 6 weeks.ResultsTen patients completed laser therapy. The average hair reduction was 60% based on visual inspection. Shaving frequency reduced from once a week to once every 6 weeks.ConclusionsLaser hair removal likely becomes the preferred method in ostomy patients. Lasers Surg. Med. 39:773–775, 2007. © 2007 Wiley‐Liss, Inc.
Dynamic skin cooling with an environmentally compatible alternative cryogen during laser surgery
Authors: Jia Wangcun , Svaasand Lars O. , Nguyen Thang B. , Nelson J. Stuart 
Published: December 2007

AbstractBackground and ObjectivesCryogen spray cooling with tetrafluoroethane (R134a) has been used to enhance epidermal protection during dermatologic laser surgery. However, R134a has a very high global warming potential (GWP = 1300). Our objective was to evaluate the cooling effectiveness of an alternative cryogen with a much lower GWP, namely liquid carbon dioxide (CO2, GWP = 1).Study Design/Materials and MethodsA thin‐film thermocouple deposited on an epoxy skin phantom was used to measure surface temperature (Ts) variations induced by R134a or CO2 sprays. The temperature distribution in the skin phantom was estimated using Ts and Duhamel's method. Impact pressure and noise level of both cryogen sprays were measured with a dynamic sensor and sound meter, respectively. Consumption of both cryogens was also evaluated.ResultsFor R134a sprays, Ts was kept almost constant after 15 milliseconds. For CO2 sprays, Ts decreased continuously during the entire spurt of 50 milliseconds. The minimum Ts induced by the CO2 sprays was lower than that induced by R134a when the spurt duration was longer than 35 milliseconds. Numerical simulation shows that CO2 sprays were able to induce very similar temperature reductions in the skin phantom as compared to R134a sprays when the spurt duration and delay time were selected appropriately. R134a sprays induced an impact pressure of 3.6 kPa, as compared to 43.1 kPa for CO2 sprays. The maximum noise level for R134a sprays was 109 dBA as compared to 135 dBA for the CO2 sprays. The R134a consumption for a 50 milliseconds spurt is 67 mg as compared to 225 mg for a CO2 spurt of the same duration.ConclusionsCO2 sprays are expected to have similar skin cooling efficacy as R134a sprays. Although the CO2 consumption is higher than R134a, its contribution to global warming is still much less than R134a. The effects of varying spurt durations on in vivo human skin and the impact on cutaneous blood flow require further investigation. Lasers Surg. Med. 39:776–781, 2007. © 2007 Wiley‐Liss, Inc.
Effect of low‐level laser therapy on bone repair: Histological study in rats
Authors: Pretel Hermes , Lizarelli Rosane F.Z. , Ramalho Lizeti T.O. 
Published: December 2007

AbstractBackground and ObjectivesBone remodeling is characterized as a cyclic and lengthy process. It is currently accepted that not only this dynamics is triggered by a biological process, but also biochemical, electrical, and mechanical stimuli are key factors for the maintenance of bone tissue. The hypothesis that low‐level laser therapy (LLLT) may favor bone repair has been suggested. The purpose of this study was to evaluate the bone repair in defects created in rat lower jaws after stimulation with infrared LLLT directly on the injured tissue.Study Design/Materials and MethodsBone defects were prepared on the mandibles of 30 Holtzman rats allocated in two groups (n = 15), which were divided in three evaluation period (15, 45, and 60 days), with five animals each. control group—no treatment of the defect; laser group—single laser irradiation with a GaAlAs semiconductor diode laser device (λ = 780 nm; P = 35 mW; t = 40 s; Θ = 1.0 mm; D = 178 J/cm2; E = 1.4 J) directly on the defect area. The rats were sacrificed at the pre‐established periods and the mandibles were removed and processed for staining with hematoxylin and eosin, Masson's Trichrome and picrosirius techniques.ResultsThe histological results showed bone formation in both groups. However, the laser group exhibited an advanced tissue response compared to the control group, abbreviating the initial inflammatory reaction and promoting rapid new bone matrix formation at 15 and 45 days (P<0.05). On the other hand, there were no significant differences between the groups at 60 days.ConclusionThe use of infrared LLLT directly to the injured tissue showed a biostimulating effect on bone remodeling by stimulating the modulation of the initial inflammatory response and anticipating the resolution to normal conditions at the earlier periods. However, there were no differences between the groups at 60 days. Lasers Surg. Med. 39:788–796, 2007. © 2007 Wiley‐Liss, Inc.
Erratum: Reciprocity of exposure time and irradiance on energy density during photoradiation on wound healing in a murine pressure ulcer model
Authors: Lanzafame Raymond J. , Stadler Istvan , Kurtz Andrew F. , Connelly Roger , Timothy Peter A. , Brondon Philip , Olson Donald 
Published: December 2007

AbstractIn this original published article, Dr. Peter, Sr's name was misprinted. It should be Timothy A. Peter, Sr.
Progression of cortical and spinal dysfunctions over time in amyotrophic lateral sclerosis
Authors: Attarian Shahram , Vedel Jean‐Pierre , Pouget Jean , Schmied Annie 
Published: December 2007

AbstractIn view of the conflicting results about the links between lower and upper motor neuron (LMN, UMN) dysfunction in amyotrophic lateral sclerosis (ALS), we undertook this study to correlate their changes over time. Single motor units (MUs) were characterized by their macro‐MU potentials, twitch amplitude, and excitatory responses to transcranial magnetic stimulation (TMS). Ten ALS patients were studied 2 to 4 times and their data were subdivided into epochs corresponding to mean disease duration of 12 (58 MUs), 20 (60 MUs), 32 (50 MUs), 43 (40 MUs), and 168 months (55 MUs). The MU size increased and the contractile effectiveness and the excitatory response rates decreased significantly with time. The contractile effectiveness of MUs producing normal excitatory responses decreased with time, whereas a gradual loss of excitatory responses was observed among MUs with normal electromechanical properties. Since no correlation was found between UMN and LMN dysfunction, we conclude that UMN and LMN probably degenerate independently in ALS. Muscle Nerve, 2008
Using forward calculations of the magnetic field perturbation due to a realistic vascular model to explore the BOLD effect
Authors: Marques José P. , Bowtell R. W. 
Published: December 2007

AbstractThis paper assesses the reliability of the infinite cylinder model used previously in the literature to simulate blood oxygenation level dependent (BOLD) signal changes. A three‐dimensional finite element method was applied to a realistic model of the cortical vasculature, and the results compared with those generated from a simple model of the vasculature as a set of independent, randomly oriented, infinite cylinders. The realistic model is based on scanning electron microscopy measurements of the terminal vascular bed in the superficial cortex of the rat. Good agreement is found between the two models with regard to the extravascular R2* and R2 dependence on the cerebral blood volume and blood oxygenation fraction. Using the realistic model, it is also possible to gain further understanding of the relative importance of intravascular and extravascular BOLD contrast. A simple parameterisation of the dependence of the relaxation rates on relative cerebral blood volume and blood–tissue susceptibility difference was carried out, allowing discussion of the variation in the form of the haemodynamic response with field strength. Copyright © 2007 John Wiley & Sons, Ltd.