bluuebunny/crossref_metadata_2025 huggingface dataset:
Pituitary cyst presenting with hyponatremia and increased secretion of brain natriuretic peptide
Authors: Son Jae-Hyun , Fujimaki Takamitsu , Tsuchiya Yoshiaki , Ishii Teruyuki , Takagi Kiyoshi , Nakagomi Tadayoshi
Published: May 2009

✓ In most cases of pituitary cyst there are no clinical symptoms and the lesions are found incidentally. The authors report the case of a 60-year-old man with a pituitary cyst causing visual disturbance and hyponatremia. The patient presented with appetite loss and general fatigue. On admission, blood workup showed severe hyponatremia (112 mEq/L), and bitemporal hemianopsia was observed on neurological examination. Magnetic resonance imaging revealed an intra- and suprasellar region cystic mass extending to the frontal base and hypothalamic area. The serum level of brain natriuretic peptide (BNP) was elevated (92 pg/ml) with polyuria and excessive Na excretion. Transsphenoidal surgery was performed to drain the cyst. The cyst wall was partially excised and the cystic fluid was aspirated. The secretion of BNP normalized postoperatively, and the hyponatremia and visual symptoms resolved. Histological examination, including an electron microscopy study, confirmed the diagnosis of a simple cyst. This appears to be the first reported case of a pituitary simple cyst associated with hyponatremia and an elevated BNP level.
Harvey Cushing and Oskar Hirsch: early forefathers of modern transsphenoidal surgery
Authors: LIU James K. , Cohen-Gadol Aaron A. , Laws Edward R. , Cole Chad D. , Kan Peter , Couldwell William T.
Published: May 2009

✓ The transnasal transsphenoidal approach is the preferred route for removal of most lesions of the sella turcica. The concept of transnasal surgery traversing the sphenoid sinus to reach the sella has existed for nearly a century. A comprehensive historical overview of the evolution of transsphenoidal surgery has been reported previously. In the present vignette, the authors focus on transsphenoidal surgery in the early 1900s, particularly on the methods advocated by Harvey Cushing and Oskar Hirsch, two prominent pituitary surgeons who pioneered the transsphenoidal technique. Cushing championed the sublabial approach, whereas Hirsch was the master of the endonasal route. Coincidentally, both surgeons independently performed the submucous septal resection for the first time on June 4, 1910. Although Cushing's and Hirsch's approaches were predicated on the work of their predecessors, their transsphenoidal procedures became the two most popular techniques and, for future generations of pituitary surgeons, laid the foundation for modern transsphenoidal surgery. In this comparative analysis, the authors compare the operative nuances of the approaches of Cushing and Hirsch and describe the contributions of these pioneers to modern transsphenoidal surgery.
Effects of a Thiosemicarbazide Camphene Derivative on Trichophyton mentagrophytes
Authors: Yamaguchi Mirian Ueda , Barbosa da Silva Ana Paula , Ueda-Nakamura Tânia , Dias Filho Benedito Prado , Conceição da Silva Cleuza , Nakamura Celso Vataru
Published: May 2009

Thiosemicarbazides are compounds known for their biological activity, particularly their antimicrobial properties, which include activity against fungi. The difficulty of treating fungal diseases induced us to assess the antifungal properties of some novel thiosemicarbazide compounds. We selected the natural products limonene and camphene as sources for the preparation of these new thiosemicarbazide derivatives. The compound N(4)-[2,2-dimethyl-3-methylnorbornane]-thiosemicarbazide (TIO C) showed an antifungal effect on Trichophyton mentagrophytes, with values of MIC = 55 mmol L-1 and MFC = 110 mmol L-1. Scanning-electron microscopy showed a decrease in mycelium development and morphological alterations of T. mentagrophytes cultured on nail fragments and treated with TIO C. In an attempt to discover its mode of action, we noted that ergosterol is apparently not a target of TIO C activity. An effect of TIO C on T. mentagrophytes cell walls and dividing cross-walls was shown by observed impairment of the fluorescence of tissues stained with calcofluor white, a specific marker for fungal chitin, suggesting that the compound can affect and damage the cell-wall structure or may interfere with its formation, during cell division, growth, and morphogenesis. This approach to the synthesis of new derivatives might provide interesting compounds with greater biological activity in pharmacological research.
Antimicrobial Activity of Six Pomegranate (Punica granatum L.) Varieties and Their Relation to Some of Their Pomological and Phytonutrient Characteristics
Authors: Duman Ahmet  D. , Ozgen Mustafa , Dayisoylu Kenan  S. , Erbil Nurcan , Durgac Coskun
Published: May 2009

Arils from six pomegranate (Punica granatum L.) varieties grown in the Mediterranean region of Turkey were tested for their antimicrobial properties by the agar diffusion and minimum inhibitory concentration (MIC) methods against seven bacteria: (Bacillus megaterium DSM 32, Pseudomonas aeruginosa DSM 9027, Staphylococcus aureus Cowan 1, Corynebacterium xerosis UC 9165, Escherichia coli DM, Enterococcus faecalis A10, Micrococcus luteus LA 2971), and threefungi (Kluvyeromyces marxianus A230, Rhodotorula rubra MC12, Candida albicans ATCC 1023). It has been observed that the pomegranate aril extracts had antimicrobial effect on all microorganisms, giving inhibition zones ranging in size from 13 to 26 mm. The MIC values for active pomegranate extracts ranged between 30 and >90 µg/mL. The results obtained appeared to confirm the antimicrobial potential of the Punica granatum varieties.
Phenoxypropylamines: Synthesis and Antiulcer Evaluation
Authors: Zhang Hui , Zhang Bao-Yan , Zhang Qian-Yun , Zhao Dong-Mei , Wang Jia-Mei
Published: May 2009

We have synthesized a number of phenoxypropylamines from N-{3-[3-(1-piperidinylmethyl)phenoxy]propyl}chloroacetamide (3). All the products have been characterized by elemental analysis, 1H-NMR and MS. The biological activity effects of the title compounds were examined. From the biological activity results, we found that two of themshowed significant gastric acid antisecretory activity.
Effect of Land Cover Heterogeneity on Soil Moisture Retrieval Using Active Microwave Remote Sensing Data
Authors: Lakhankar Tarendra , Ghedira Hosni , Temimi Marouane , Azar Amir  E. , Khanbilvardi Reza
Published: May 2009

This study addresses the issue of the variability and heterogeneity problems that are expected from a sensor with a larger footprint having homogenous and heterogeneous sub-pixels. Improved understanding of spatial variability of soil surface characteristics such as land cover and vegetation in larger footprint are critical in remote sensing based soil moisture retrieval. This study analyzes the sub-pixel variability (standard deviation of sub-grid pixels) of Normalized Difference Vegetation Index and SAR backscatter. Back-propagation neural network was used for soil moisture retrieval from active microwave remote sensing data from Southern Great Plains of Oklahoma. The effect of land cover heterogeneity (number of different vegetation species within pixels) on soil moisture retrieval using active microwave remote sensing data was investigated. The presence of heterogeneous vegetation cover reduced the accuracy of the derived soil moisture using microwave remote sensing data. The results from this study can be used to characterize the uncertainty in soil moisture retrieval in the context of Soil Moisture Active and Passive (SMAP) mission which will have larger footprint.
Micro-Pattern Guided Adhesion of Osteoblasts on Diamond Surfaces
Authors: Rezek Bohuslav , Michalíková Lenka , Ukraintsev Egor , Kromka Alexander , Kalbacova Marie
Published: May 2009

Microscopic chemical patterning of diamond surfaces by hydrogen and oxygen surface atoms is used for self-assembly of human osteoblastic cells into micro-arrays. The cell adhesion and assembly is further controlled by concentration of cells (2,500-10,000 cells/cm2)and fetal bovine serum (0-15%). The cells are characterized by fluorescence microscopy of actin fibers and nuclei. The serum protein adsorption is studied by atomic force microscopy (AFM). The cells are arranged selectively on O-terminated patterns into 30-200 μm wide arrays. Higher cell concentrations allow colonization of unfavorable H-terminated regions due to mutual cell communication. There is no cell selectivity without the proteins in the medium. Based on the AFM, the proteins are present on both H- and O-terminated surfaces. Pronounced differences in their thickness, surface roughness, morphology, and phase imagesindicate different conformation of the proteins and explain the cell selectivity.
Metal Ion Enhanced Charge Transfer in a Terpyridine-bis-Pyrene System
Authors: D’Aléo Anthony , Cecchetto Elio , De Cola Luisa , Williams René M.
Published: May 2009

The synthesis, electrochemical and photophysical properties of a branched molecule 3,5-bis(pyrene-1-yl)-4'-phenyl-2,2':6',2''-terpyridine are reported. Spectroscopy in different solvents reveals that an optical electron transfer from the pyrene donor to the terpyridyl electron acceptor can occur in polar media, as the system displays both charge transfer (CT) absorption and CT emission. Furthermore, the study of the zinc complex as well as the bis-protonated form shows an enhancement of the electron transfer character of the system, by an increase of the acceptor strength. This is accompanied by a large increase of the non-radiative processes. With sub-nanosecond transient absorption spectroscopy, the CT state, consisting of the pyrene radical cation and the terpyridine radical anion, has been detected. At room temperature, the study of the nanosecond transient absorption spectra reveals the formation of a low-lying triplet excited state that we attribute to the pyrene moiety through which the CT state decays. At 77K, the absence of the terpyridine triplet emission also suggests the population of a low-lying triplet state of the pyrene unit.
Patterns of hybridization and introgression between invasiveUlmus pumila(Ulmaceae) and nativeU. rubra
Authors: Zalapa Juan E. , Brunet Johanne , Guries Raymond P.
Published: May 2009

Natural hybridization between introduced species and their native congeners occurs frequently and can create serious conservation concerns.Ulmus pumila(Siberian elm) is an introduced Asian elm species that has naturalized in the United States and is now considered invasive in 41 states. Red elm (U. rubra), a native to the eastern United States, often occurs in sympatry with Siberian elm, and the two species are thought to hybridize. Here, we genetically characterized reference populations of the two elm species to identify species‐specific microsatellite alleles. These markers were used to classify individuals in putative hybrid zones as parental species or hybrids, assess the extent of hybridization, and track patterns of introgression. We identified nineU. rubra, 32U. pumila, and 51 hybrid individuals in our hybrid zones. Of the 51 hybrids, 35 were classified as first‐generation hybrids and 16 as backcrosses. The majority of the backcrosses (88%) were introgressed towardU. pumila. Our classification of genotypes was consistent whether we used manual classification, principal coordinate analyses or Bayesian clustering. We observed greater genetic diversity and new combination of alleles in the hybrids. Our study indicates widespread hybridization betweenU. pumilaandU. rubraand an asymmetric pattern of introgression towardU. pumila.
Peak Flow Rate During Induced Cough: A Predictor of Successful Decannulation of a Tracheotomy Tube in Neurosurgical Patients
Authors: Chan Linda Y. Y. , Jones Alice Y. M. , Chung Raymond C. K. , Hung K. N.
Published: May 2009

Background An accurate predictor of successful decannulation in neurosurgical patients that indicates the best time for tracheotomy decannulation would minimize the risks of continued cannulation and unsuccessful decannulation.

Objective To determine whether the peak flow rate during induced cough is an appropriate predictor of successful decannulation.

Methods A total of 32 neurosurgical patients with a tracheotomy were enrolled. The highest peak expiratory flow rate during 3 induced coughs, the total volume of tracheal secretions collected in 6 hours, and scores on the Glasgow Coma Scale were recorded. Logistic regression analysis was applied to determine the relationship between these variables and successful decannulation (reintubation not required within 72 hours).

Results Decannulation was attempted in 23 of 32 patients. The remaining 9 patients were considered clinically inappropriate for the procedure. Of the 23 patients decannulated, 2 required reinsertion of the tracheotomy tube. Analysis revealed that peak flow rate during induced cough (odds ratio, 1.12; 95% confidence interval, 1.02–1.23) was independently associated with successful decannulation (accuracy, 75%; sensitivity, 85.7%; specificity, 54.5%). The receiver operating characteristic curve indicated an optimal cutoff point of 29 L/min.

Conclusion Measurement of peak flow rate during induced cough is a simple and reproducible intervention that improves predictability of successful decannulation in patients with tracheotomy.
N‐Heterocyclic Carbene Gold(I) Catalyzed Transformation of N‐Tethered 1,5‐Bisallenes to 6,7‐Dimethylene‐3‐azabicyclo[3.1.1]heptanes
Authors: Kim Soo Min , Park Ji Hoon , Kang Youn Kyung , Chung Young Keun
Published: May 2009

Die losen Enden verknüpft: N‐Ts‐verbrückte Bisallene (N‐Ts=N‐(p‐Tolylsulfonamid) liefern in Gegenwart eines kationischen Gold‐NHC‐Katalysators (NHC=N‐heterocyclisches Carben) neuartige Cycloisomerisierungsprodukte, 6,7‐Dimethylenazabicyclo[3.1.1]heptane, in hohen Ausbeuten (siehe Schema; IPr=N,N′‐Bis(2,6‐diisopropylphenyl)imidazol‐2‐yliden).

magnified image
Palladium‐Catalyzed Cyanation of CarbonCarbon Triple Bonds Under Aerobic Conditions
Authors: Arai Shigeru , Sato Takashi , Koike Yuka , Hayashi Michino , Nishida Atsushi
Published: May 2009

Ohne Sauerstoff geht nichts: Die Titelreaktion nutzt zwei Arten der Cyanierung, eine syn‐ und eine anti‐Cyanopalladierung, als Schlüsselschritte dieser katalytischen Reaktion. Die Umsetzung eignet sich auch für die dicyanierende Cyclisierung von Diin‐ und Eninderivaten (siehe Schema).

magnified image
Local and Collective Motions in Precise Polyolefins with Alkyl Branches: A Combination of 2H and 13C Solid‐State NMR Spectroscopy
Authors: Wei Yuying , Graf Robert , Sworen John C. , Cheng Chi‐Yuan , Bowers Clifford R. , Wagener Kenneth B. , Spiess Hans Wolfgang
Published: May 2009

Die Beweglichkeit linearer Polymere ändert sich beim Verzweigen, was die Prozessierbar‐ und Ziehfähigkeit stark beeinflusst. Regelmäßig verzweigte Modellpolyolefine wurden mit modernen Festkörper‐NMR‐Techniken untersucht und Verdrillungen um die Verzweigungen in den kristallinen Bereichen identifiziert. Bei wenigen Verzweigungen sind die Verdrillbewegungen entkoppelt, bei hoher Verzweigung findet eine kollektive Bewegung statt (siehe Bild).

magnified image
An Optical Approach for Drug Screening Based on Light‐Harvesting Conjugated Polyelectrolytes
Authors: An Lingling , Liu Libing , Wang Shu , Bazan Guillermo C.
Published: May 2009

Wirkstoffe schalten das Licht aus: Konjugierte Polyelektrolyte (CPEs) wurden in Fluoreszenzassays zum Echtzeit‐Screening von niedermolekularen Verbindungen genutzt (siehe Bild), welche die für die virale Replikation wichtige RNA‐Protein‐Komplexierung verhindern und damit als Kandidaten für die weitere Wirkstoffentwicklung dienen können.

magnified image
Enantiospezifische Synthese und Allylierung ausschließlich Kohlenstoff‐substituierter, α‐chiraler Allylstannane
Authors: Schmidtmann Eric S. , Oestreich Martin
Published: May 2009

Endlich frei wurde der Weg zu den Titelverbindungen in nahezu enantiomerenreiner Form mit einem Bis(triorganostannyl)zinkreagens (siehe Schema). Diastereoselektive thermische (links) und Lewis‐Säure‐vermittelte Folgereaktionen (rechts) veranschaulichen das Synthesepotenzial dieser Verbindungen.

magnified image
Tellurium(II)‐Centered Dications from the Pseudohalide “Te(OTf)2”
Authors: Dutton Jason L. , Tuononen Heikki M. , Ragogna Paul J.
Published: May 2009

Pyridin‐ oder Carbenderivate als Liganden ermöglichen die Synthese von tellurzentrierten Dikationen, darunter einem dikationischen Telluranalogon des kürzlich synthetisierten „Carbodicarbens“, in hoher Ausbeute. Entscheidend für den Zugang zu diesen Verbindungen ist die Isolierung einer basenstabilisierten Form von TeOTf2 (siehe Struktur), einem neuen hoch elektrophilen Reagens für die Tellurchemie.

magnified image
Palladium‐Catalyzed Cyanation of CarbonCarbon Triple Bonds Under Aerobic Conditions
Authors: Arai Shigeru , Sato Takashi , Koike Yuka , Hayashi Michino , Nishida Atsushi
Published: May 2009

Essential oxygen: The title transformation involves two different modes of cyanation, syn and anti cyanopalladation, as the key steps in this catalytic reaction. These processes enable successful dicyanative cyclization of diyne and enyne derivatives (see scheme).

magnified image
Amplification of the Cotton Effect of a Single Chromophore through Liposomal Ordering—Stereochemical Assignment of Plakinic Acids I and J
Authors: Dalisay Doralyn S. , Quach Tim , Nicholas Gillian N. , Molinski Tadeusz F.
Published: May 2009

A dramatic effect is observed when acyclic N‐(2‐naphthamides) of medium‐chain 1‐amino‐2‐methylalkanes are partially ordered with the help of liposomes: the Cotton effect arising from π–π* transitions of the terminal naphthamide chromophor is enormously enhanced. This effect was exploited to assign the configuration of new polyketide peroxides such as 1 from the sponge Plakortis halichondroides.

magnified image
Enantiospecific Synthesis and Allylation of All‐Carbon‐Substituted α‐Chiral Allylic Stannanes
Authors: Schmidtmann Eric S. , Oestreich Martin
Published: May 2009

Once difficult to obtain, the title compounds can be prepared in virtually enantiomerically pure form with a bis(triorganostannyl) zinc reagent (see scheme). Subsequent diastereoselective thermal (left) and Lewis acid promoted reactions (right) illustrate the synthetic potential of these compounds.

magnified image
A Powerful Chiral Counteranion Motif for Asymmetric Catalysis
Authors: García‐García Pilar , Lay Frank , García‐García Patricia , Rabalakos Constantinos , List Benjamin
Published: May 2009

Room to swing a cat: A chiral disulfonimide has been designed as a powerful new motif for asymmetric catalysis. As a first illustration, a highly efficient and enantioselective Mukaiyama aldol reaction has been developed (see scheme). The actual catalyst is proposed to be an N‐silyl imide which is generated in situ.

magnified image
A one‐pot, stereoselective synthesis of 2‐ethoxycarbonyl‐substituted 1,3‐dienes and 1,3‐enynes by hydrostannylation–Stille tandem reaction of tributyltin hydride with alkynyl esters and alkenyl or alkynyl halides
Authors: Cai Mingzhong , Fang Xiaoniu , Dai Ruchun , Zha Lingfang
Published: May 2009

2‐Ethoxycarbonyl‐substituted 1,3‐dienes and 1,3‐enynes can be stereoselectively synthesized in one pot under mild conditions, in good yields, by the palladium‐catalyzed hydrostannylation of alkynyl esters, followed by Stille coupling with alkenyl or alkynyl halides, respectively. Copyright © 2009 John Wiley & Sons, Ltd.
Analysis of query keywords of sports‐related queries using visualization and clustering
Authors: Zhang Jin , Wolfram Dietmar , Wang Peiling
Published: May 2009

The authors investigated 11 sports‐related query keywords extracted from a public search engine query log to better understand sports‐related information seeking on the Internet. After the query log contents were cleaned and query data were parsed, popular sports‐related keywords were identified, along with frequently co‐occurring query terms associated with the identified keywords. Relationships among each sports‐related focus keyword and its related keywords were characterized and grouped using multidimensional scaling (MDS) in combination with traditional hierarchical clustering methods. The two approaches were synthesized in a visual context by highlighting the results of the hierarchical clustering analysis in the visual MDS configuration. Important events, people, subjects, merchandise, and so on related to a sport were illustrated, and relationships among the sports were analyzed. A small‐scale comparative study of sports searches with and without term assistance was conducted. Searches that used search term assistance by relying on previous query term relationships outperformed the searches without the search term assistance. The findings of this study provide insights into sports information seeking behavior on the Internet. The developed method also may be applied to other query log subject areas.
Normal and abnormal anatomy of the cerebellar vermis in midgestational human fetuses
Authors: Kapur Raj P. , Mahony Barry S. , Finch Lisa , Siebert Joseph R.
Published: May 2009

BACKGROUND:

Evaluation of the cerebellar vermis is an important component of fetal autopsy, but lack of an established approach, inadequate normal anatomic data, and the subtle nature of some cerebellar malformations negatively affect concordance between prenatal ultrasound and autopsy diagnoses.

METHODS:

Gross anatomy and sagittal histologic sections of vermis from 26 midgestation fetuses with no posterior fossa anomalies detected by prenatal ultrasound or autopsy were examined to establish stage‐specific norms. These were compared to data from three fetuses with prenatal ultrasound diagnoses of hypoplasia or absence of the cerebellar vermis, each of which had no or equivocal gross cerebellar malformation at autopsy.

RESULTS:

Two findings segregated cases from controls: (1) The ratio of the rostro‐caudal length of the vermis to that of the cerebellar hemispheres was shorter for cases (<0.7), in comparison with controls (0.7–1). (2) The lobules of the vermis, particularly in the posterior lobe, were less arborized, and the nodulus (caudal‐most lobule) was elongated. Prenatal sonograms from the three cases predicted more severe vermis hypoplasia than was evident at autopsy.

CONCLUSIONS:

Prenatal ultrasound images that suggest moderate‐to‐severe hypoplasia of the cerebellar vermis may reflect relatively subtle malformations, which are recognized histologically by direct comparison with stage‐matched control data. The data in this series and others suggest a somewhat consistent pattern of lobular malformation, which affects the caudal cerebellum, particularly the nodulus, most severely. Rotation of the cerebellum, secondary to an enlarged fourth ventricle, may account for discordance between ultrasound and autopsy findings. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc.
Effect of ultra‐strong static magnetic field on bacteria: Application of Fourier‐transform infrared spectroscopy combined with cluster analysis and deconvolution
Authors: Hu Xing , Qiu Zunan , Wang Yerui , She Zichao , Qian Guangren , Ren Zhongming
Published: May 2009

A new method based on Fourier‐transform infrared (FTIR) spectroscopy combined with cluster analysis and deconvolution was established to investigate the biological effect of an ultra‐strong static magnetic field (SMF) of 10.0 T on Escherichia coli and Staphylococcus aureus. FTIR spectroscopy was applied to characterize the spectroscopic fingerprints of these bacterial cells with or without the treatment of the SMF. After the calculation, the results of cluster analysis indicated that the SMF had significant effects on E. coli compared with S. aureus, and the effects were reflected by the changes of spectral region of 1500–1200 cm−1. The deconvolution results of this major indication region showed that the composition and conformation of nucleic acid, protein, and fatty acid of E. coli were altered under the magnetic conditions. Bioelectromagnetics 30:500–507, 2009. © 2009 Wiley‐Liss, Inc.
Chemiluminescence from luminol solution after illumination of a 355 nm pulse laser
Authors: Min Lingyue , Wu Xing‐Zheng
Published: May 2009

Chemiluminescence (CL) on the time scale of microseconds to milliseconds from luminol solution after illumination of a 355 nm pulse laser is reported. It was found that the CL is the emission from 3‐aminophthalate ion (AP*). In CL decay after the pulse laser illumination, a peak was observed from about 200 to 30 µs depending on the laser power and the luminol concentration. It seemed that there was a fast and slow decay process; their kinetics were greatly dependent on the laser power and the luminol concentration. Dissolved oxygen was involved in the CL and played the same role on the whole time scale of microseconds to milliseconds. Involvement of reactive oxygen species such as H2O2, 1O2, O2•− and OH in the CL was examined by adding their scavengers. Experimental results suggested that the possibility of involvement of H2O2 and 1O2 in the CL was low. The CL in time periods less than 50 µs might be related to •OH. The •O2•−‐induced CL increased with time after 50 µs and became dominant on the time scale of milliseconds. The CL was considered to be caused by both the photoionization and type I reaction mechanisms. Copyright © 2009 John Wiley & Sons, Ltd.
Review: Correlations between oxygen affinity and sequence classifications of plant hemoglobins
Authors: Smagghe Benoit J. , Hoy Julie A. , Percifield Ryan , Kundu Suman , Hargrove Mark S. , Sarath Gautam , Hilbert Jean‐Louis , Watts Richard A. , Dennis Elizabeth S. , Peacock W. James , Dewilde Sylvia , Moens Luc , Blouin George C. , Olson John S. , Appleby Cyril A.
Published: May 2009

Plants express three phylogenetic classes of hemoglobins (Hb) based on sequence analyses. Class 1 and 2 Hbs are full‐length globins with the classical eight helix Mb‐like fold, whereas Class 3 plant Hbs resemble the truncated globins found in bacteria. With the exception of the specialized leghemoglobins, the physiological functions of these plant hemoglobins remain unknown. We have reviewed and, in some cases, measured new oxygen binding properties of a large number of Class 1 and 2 plant nonsymbiotic Hbs and leghemoglobins. We found that sequence classification correlates with distinct extents of hexacoordination with the distal histidine and markedly different overall oxygen affinities and association and dissociation rate constants. These results suggest strong selective pressure for the evolution of distinct physiological functions. The leghemoglobins evolved from the Class 2 globins and show no hexacoordination, very high rates of O2 binding (∼250 μM−1 s−1), moderately high rates of O2 dissociation (∼5–15 s−1), and high oxygen affinity (Kd or P50 ≈ 50 nM). These properties both facilitate O2 diffusion to respiring N2 fixing bacteria and reduce O2 tension in the root nodules of legumes. The Class 1 plant Hbs show weak hexacoordination (KHisE7 ≈ 2), moderate rates of O2 binding (∼25 μM−1 s−1), very small rates of O2 dissociation (∼0.16 s−1), and remarkably high O2 affinities (P50 ≈ 2 nM), suggesting a function involving O2 and nitric oxide (NO) scavenging. The Class 2 Hbs exhibit strong hexacoordination (KHisE7 ≈ 100), low rates of O2 binding (∼1 μM−1 s−1), moderately low O2 dissociation rate constants (∼1 s−1), and moderate, Mb‐like O2 affinities (P50 ≈ 340 nM), perhaps suggesting a sensing role for sustained low, micromolar levels of oxygen. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 1083–1096, 2009.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Simulating gaze attention behaviors for crowds
Authors: Grillon Helena , Thalmann Daniel
Published: May 2009

Crowd animation is a topic of high interest which offers many challenges. One of the most important is the trade‐off between rich, realistic behaviors, and computational costs. To this end, much effort has been put into creating variety in character representation and animation. Nevertheless, one aspect still lacking realism in virtual crowd characters resides in their attention behaviors. In this paper, we propose a framework to add gaze attention behaviors to crowd animations. First, we automatically extract interest points from character or object trajectories in pre‐ existing animations. For a given character, we assign a set of elementary scores based on parameters such as distance or speed to all other characters or objects in the scene. We then combine these subscores in an overall scoring function. The scores obtained from this function form a set of gaze constraints that determine where and when each character should look. We finally enforce these constraints with an optimized dedicated gaze Inverse Kinematics (IK) solver. It first computes the displacement maps for the constraints to be satisfied. It then smoothly propagates these displacements over an automatically defined number of frames. We demonstrate the efficiency of our method and our visually convincing results through various examples. Copyright © 2009 John Wiley & Sons, Ltd.
Pressure corrected SPH for fluid animation
Authors: Bao Kai , Zhang Hui , Zheng Lili , Wu Enhua
Published: May 2009

We present a novel pressure correction scheme for the Smoothed Particle Hydrodynamics (SPH) for fluid animation. In the conventional SPH method, equations of state (EOS) are employed to relate the pressure to the particle density. To enforce the volume conservation, high speeds of sound are usually required, which leads to very small time steps and noisy pressure distribution. The problem remains one of the main reasons of numerical instability in SPH. In the paper, a new extra pressure correction scheme is proposed to transport the local pressure disturbance to the neighboring area and no solution of the Poisson equation is required. As a result, smoother pressure distribution and more efficient simulation are achieved. The proposed method has been used to simulate free surface problems. The results demonstrate the validation of the present SPH method. Surface tension and fluid fragmentation can be well handled. Copyright © 2009 John Wiley & Sons, Ltd.
A Targeted Releasable Affinity Probe (TRAP) for In Vivo Photocrosslinking
Authors: Yan Ping , Wang Ting , Newton Gregory J. , Knyushko Tatyana V. , Xiong Yijia , Bigelow Diana J. , Squier Thomas C. , Mayer M. Uljana
Published: May 2009

A protein TRAP: The in vivo photocrosslinking of TRAP after its intracellular targeting to a binding sequence on the bait protein stabilizes protein interactions. Because the crosslinker is releasable, simple mass spectrometry can be used to identify the protein binding sites after purification.

magnified image

Protein crosslinking, especially coupled to mass‐spectrometric identification, is increasingly used to determine protein binding partners and protein–protein interfaces for isolated protein complexes. The modification of crosslinkers to permit their targeted use in living cells is of considerable importance for studying protein‐interaction networks, which are commonly modulated through weak interactions that are formed transiently to permit rapid cellular response to environmental changes. We have therefore synthesized a targeted and releasable affinity probe (TRAP) consisting of a biarsenical fluorescein linked to benzophenone that binds to a tetracysteine sequence in a protein engineered for specific labeling. Here, the utility of TRAP for capturing protein binding partners upon photoactivation of the benzophenone moiety has been demonstrated in living bacteria and mammalian cells. In addition, ligand exchange of the arsenic–sulfur bonds between TRAP and the tetracysteine sequence to added dithiols results in fluorophore transfer to the crosslinked binding partner. In isolated protein complexes, this release from the original binding site permits the identification of the proximal binding interface through mass spectrometric fragmentation and computational sequence identification.
Synthesis and Application of Peptide Arrays: Quo Vadis SPOT Technology
Authors: Volkmer Rudolf
Published: May 2009

Hitting the SPOT: In 1992, Ronald Frank published the first seminal paper on simultaneous parallel synthesis of multiple peptides on filter paper. He defined the approach as SPOT synthesis, an easy technique for positionally addressable, parallel chemical synthesis on a membrane support. Here, a basic overview of this technology is presented and a recently published applications are highlighted. At the end, the future of peptide arrays is discussed.

magnified image
Selective Antifolates for Chemically Labeling Proteins in Mammalian Cells
Authors: Pedró Rosa Laura E. , Reddy D. Rajasekhar , Queener Sherry F. , Miller Lawrence W.
Published: May 2009

Antifolate labels: Molecules that bind specifically and with high affinity to proteins can be developed into powerful tools for chemical biology. The interaction between substituted 5‐benzyl pyrimidines and dihydrofolate reductase can be exploited for chemically labeling fusion proteins in mammalian cells.

magnified image
Higher‐order analogues of the Tracy‐Widom distribution and the Painlevé II hierarchy
Authors: Claeys Tom , Krasovsky Igor , Its Alexander
Published: May 2009

We study Fredholm determinants related to a family of kernels that describe the edge eigenvalue behavior in unitary random matrix models with critical edge points. The kernels are natural higher‐order analogues of the Airy kernel and are built out of functions associated with the Painlevé I hierarchy. The Fredholm determinants related to those kernels are higher‐order generalizations of the Tracy‐Widom distribution. We give an explicit expression for the determinants in terms of a distinguished smooth solution to the Painlevé II hierarchy. In addition, we compute large gap asymptotics for the Fredholm determinants. © 2009 Wiley Periodicals, Inc.
Well‐posedness for compressible Euler equations with physical vacuum singularity
Authors: Jang Juhi , Masmoudi Nader
Published: May 2009

An important problem in the theory of compressible gas flows is to understand the singular behavior of vacuum states. The main difficulty lies in the fact that the system becomes degenerate at the vacuum boundary, where the characteristic speeds u ± c coincide and have unbounded spatial derivative since c behaves like x1/2 close to the boundary. In this paper, we overcome this difficulty by presenting a new formulation and new energy spaces. We establish the local‐in‐time well‐posedness of one‐dimensional compressible Euler equations for isentropic flows with the physical vacuum singularity in some spaces adapted to the singularity. © 2009 Wiley Periodicals, Inc.
Neoepitopes reveal the features of type II collagen cleavage and the identity of a collagenase involved in the transformation of the epiphyses anlagen in development
Authors: Lee Eunice R. , Lamplugh Lisa , Kluczyk Beata , Leblond Charles P. , Mort John S.
Published: May 2009

In long bone development, the evolution of the cartilaginous anlagen into a secondary ossification center is initiated by the formation of canals. The excavation to create the canals is achieved through lysis of the two major cartilage components, aggrecan, and the type II collagen (COL2) fibril. The present study examines the lysis of the fibril. Because it is known that matrix metalloproteinases (MMPs) cleave COL2 in vitro at the Gly775‐Leu776 bond, it has been reasoned that, if such cleavage is detected in relation to the canals, it can be concluded that a collagenase is involved. Furthermore, because MMPs undergo change in domain structure with activation resulting in propeptide domain loss then, if such a loss is revealed in relation to the cleavage of COL2, this MMP is likely involved. The collective findings reveal that COL2 is attacked at the afore‐described susceptible peptide bond at the surface of cartilage canals and, that MMP‐13 cleaves it. Developmental Dynamics 238:1547–1563, 2009. © 2009 Wiley‐Liss, Inc.
In vitro organogenesis from undifferentiated cells in Xenopus
Authors: Asashima Makoto , Ito Yuzuru , Chan Techuan , Michiue Tatsuo , Nakanishi Mio , Suzuki Kan , Hitachi Keisuke , Okabayashi Koji , Kondow Akiko , Ariizumi Takashi
Published: May 2009

Amphibians have been used for over a century as experimental animals. In the field of developmental biology in particular, much knowledge has been accumulated from studies on amphibians, mainly because they are easy to observe and handle. Xenopus laevis is one of the most intensely investigated amphibians in developmental biology at the molecular level. Thus, Xenopus is highly suitable for studies on the mechanisms of organ differentiation from not only a single fertilized egg, as in normal development, but also from undifferentiated cells, as in the case of in vitro organogenesis. Based on the established in vitro organogenesis methods, we have identified many genes that are indispensable for normal development in various organs. These experimental systems are useful for investigations of embryonic development and for advancing regenerative medicine. Developmental Dynamics 238:1309–1320, 2009. © 2009 Wiley‐Liss, Inc.
Finding partners: How BMPs select their targets
Authors: Blitz Ira L. , Cho Ken W.Y.
Published: May 2009

The bone morphogenetic protein (BMP) signaling pathway is a conserved and evolutionarily ancient regulatory module affecting a large variety of cellular behaviors. The evolutionary flexibility in using BMP responses presumably arose by co‐option of a canonical BMP signaling cascade to regulate the transcription of diverse batteries of target genes. This begs the question of how seemingly interchangeable BMP signaling components elicit widely different outputs in different cell types, an important issue in the context of understanding how BMP signaling integrates with gene regulatory networks to control development. Because a molecular understanding of how BMP signaling activates different batteries of target genes is an essential prerequisite to comprehending the roles of BMPs in regulating cellular responses, here we review the current knowledge of how BMP‐regulated target genes are selected by the signal transduction machinery. We highlight recent studies suggesting the evolutionary conservation of BMP target gene regulation signaling by Schnurri family zinc finger proteins. Developmental Dynamics 238:1321–1331, 2009. © 2009 Wiley‐Liss, Inc.
Stabilization of {RuNO}6 and {RuNO}7 States in [RuII(trpy)(bik)(NO)]n+ {trpy = 2,2′:6′,2″‐terpyridine, bik = 2,2′‐bis(1‐methylimidazolyl) ketone} – Formation, Reactivity, and Photorelease of Metal‐Bound Nitrosyl
Authors: De Prinaka , Sarkar Biprajit , Maji Somnath , Das Atanu Kumar , Bulak Ece , Mobin Shaikh M. , Kaim Wolfgang , Lahiri Goutam Kumar
Published: May 2009

Ruthenium nitrosyl complexes have been isolated in the {RuNO}6 and {RuNO}7 configurations, employing the following reaction pathway for [Ru(trpy)(bik)(X)]n+: X = Cl–, [1](ClO4) → X = CH3CN, [2](ClO4)2 → X = NO2–, [3](ClO4) → X = NO+, [4](ClO4)3 → X = NO·, [4](ClO4)2. The single‐crystal X‐ray structures of [1](ClO4)·(C6H6)·H2O, [2](ClO4)2·H2O, and [3](ClO4)·H2O have been determined. The successive NO+/NO· (reversible) and NO·/NO– (irreversible) reduction processes of [4]3+ appear at +0.36 and –0.40 V vs. SCE, respectively. While the ν(C=O) frequency of the bik ligand at about 1630 cm–1 is largely invariant on complexation and reduction, the ν(NO) frequency for the {RuNO}6 state in [4]3+ at 1950 cm–1 shifts to about 1640 cm–1 on one‐electron reduction to the {RuNO}7 form in [4]2+, reflecting the predominant NO+ → NO· character of this electron transfer. However, a sizeable contribution from ruthenium with its high spin‐orbit coupling constant to the singly occupied molecular orbital (SOMO) is apparent from the enhanced g anisotropy in the EPR spectrum [4]2+ (g1 = 2.015, g2 = 1.995, g3 = 1.881; gav = 1.965; Δg = 0.134). The {RuNO}6 unit in [4]3+ reacts with OH– via an associatively activated process (ΔS# = –126.5 ± 2 J K–1 mol–1) with a second‐order rate constant of k = 3.3 × 10–2 M–1 s–1, leading to the corresponding nitro complex [3]+. On exposure to light both {RuNO}6 and {RuNO}7 in [4]3+ and [4]2+ undergo Ru–NO photocleavage in CH3CN via the formation of [Ru(trpy)(bik)(CH3CN)]2+, [2]2+. The rate of photocleavage of the RuII–NO+ bond in [4]3+ (kNO, 8.57 ×10–1 s–1, t1/2 = 0.80 s) is found to be much faster than that of the RuII–NO· bond in [4]2+, [kNO·, 5.45 × 10–4 s–1, t1/2 = 21.2 min (= 1272 s)]. The photoreleased nitrosyl can be trapped as an Mb‐NO adduct.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Tuning Electronic Properties of Biomimetic [2Fe‐2S] Clusters by Ligand Variations
Authors: Ballmann Joachim , Dechert Sebastian , Demeshko Serhiy , Meyer Franc
Published: May 2009

Electronic effects of coordinated thiolate ligands on biomimetic [2Fe‐2S] cluster cores have been examined by using three 2,2′‐dithiobiphenyl chelate ligands that differ by the backbone substituents (Cl, H, tBu). While the X‐ray crystallographic analyses show little structural variation and Mössbauer spectra reveal only subtle differences for the three complexes 1–3, superconducting quantum interference device (SQUID) magnetic data and UV/Vis spectroscopy in solution demonstrate that the different ligand environments cause significant electronic changes in the cluster cores. In particular, potentials for the one‐electron reduction differ drastically over almost 0.5 V among the series. Due to the tight chelate arrangement, the reduced mixed‐valent species are relatively stable on the electrochemical time scale, which is unusual for all‐S‐ligated [2Fe‐2S] systems. The set of new complexes 1–3 thus provides a valuable platform to investigate reactivity patterns and the effect of electronic variations in biomimetic [2Fe‐2S] clusters. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Organometallic Osmium(II) and Ruthenium(II) Biphenyl Sandwich Complexes: X‐ray Crystal Structures and 187Os NMR Spectroscopic Studies in Solution
Authors: Gray Jennifer C. , Pagelot Alain , Collins Anna , Fabbiani Francesca P. A. , Parsons Simon , Sadler Peter J.
Published: May 2009

We report the synthesis of the ruthenium(II) and osmium(II) organometallic sandwich complexes [Ru(η6‐bip)2](OTf)2 (1) and [Os(η6‐bip)2](OTf)2 (2) containing biphenyl (bip) as the arene ligand, and the X‐ray crystal structures of 1·MeOH and 2. The unit cell of the osmium complex contains molecules in which the unbound phenyl ring of the biphenyl ligands exists in both staggered and eclipsed configurations, whereas for the ruthenium complex the rings are only eclipsed. Both crystal structures possess CH/π and π–π stacking interactions. 187Os (nuclear spin 1/2, natural abundance of 1.64 %) has a very low gyromagnetic ratio and is one of the most insensitive nuclei in the periodic table. We show that inverse NMR spectroscopic detection by the use of 1H/187Os heteronuclear multiple bond correlation (HMBC) spectroscopy allows the ready observation of the 187Os resonance of complex 2 via couplings to arene ring protons. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Diet‐dependent occurrence of CLA isomers in rumen and duodenal digesta of slaughtered bulls
Authors: Dannenberger Dirk , Nuernberg Karin , Nuernberg Gerd
Published: May 2009

This study examined the effects of linolenic acid‐rich vs. linoleic acid‐rich feeding system on the occurrence of individual CLA isomers in the rumen and duodenum digesta of German Holstein and German Simmental bulls using Ag+‐HPLC/DAD. The diet affected the biosynthesis of individual CLA isomers in the rumen of the bulls of both breeds. The isomer t‐11,c‐13 CLA was detected as the most abundant isomer in the rumen of linolenic acid‐rich diet‐fed bulls, up to six times higher compared to linoleic acid‐rich diet‐fed bulls. However, the main isomer in muscle lipid, c‐9,t‐11 CLA, was produced to a low extent in the rumen of linolenic acid‐rich diet‐fed bulls compared to higher concentrations of this isomer in the rumen of linoleic acid‐rich diet‐fed bulls. The isomers t‐7,c‐9 CLA and t‐8,c‐10 CLA were not present in the rumen samples of bulls fed both diets; however, abundant t‐7,c‐9 CLA was identified in the duodenum. The CLA isomers t‐12,t‐14 CLA and t‐11,t‐13 CLA were identified as the main t,t CLA isomers in the rumen, and were significantly enhanced in the rumen of linolenic acid‐rich diet‐fed compared to linoleic acid‐rich diet‐fed bulls. In contrast to c‐9,t‐11 CLA, the t,t CLA isomers seem to be biosynthesized predominantly in the rumen, further transported via the duodenum and finally deposited in the tissue lipids mainly in linolenic acid‐rich diet‐fed bulls. This was shown earlier for muscle and subcutaneous fat samples from the same animal experiment.
Catalytic Enantioselective Aldol Additions to Ketones
Authors: Adachi Shinya , Harada Toshiro
Published: May 2009

Enantioselective aldol addition to ketones has received growing attention since the resulting tertiary aldols are valuable building blocks for many biologically active compounds. Recently, several catalytic methodologies have been developed based on the activation of acceptor ketones and/or nucleophile enolates, overcoming problems associated with the lower reactivity and decreased steric discrimination of ketones compared to aldehydes. This microreview presents an overview of the progresses in the catalytic enantioselective aldol additions to ketones. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
An Exhaustive Conformational Evaluation of the HIV‐1 Inhibitor BMS‐378806 through Theoretical Calculations and Nuclear Magnetic Resonance Spectroscopy
Authors: Colombo Diego , Villa Stefania , Solano Lucrezia , Legnani Laura , Marinone Albini Franca , Toma Lucio
Published: May 2009

BMS‐378806 (1) is an azaindole derivative known to interfere with the HIV‐1 entry process by targeting the viral gp120 envelope glycoprotein and inhibiting its interaction to cellular CD4 receptors. To give a detailed comprehension of its conformational features, a theoretical study of 1 was performed at the B3LYP/6‐31G(d) level of calculation. Tenths of populated conformations were located and grouped into four families corresponding to the possible arrangements at the two planar amido functions. In agreement with these results, the high‐field 1H NMR spectrum of 1, recorded at 248 K, showed four distinct series of signals easily attributable to each family, thus confirming on experimental grounds the very high degree of conformational mobility of the compound. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Intramolecular Acceleration of Asymmetric Epoxide Ring‐Opening by Dendritic Polyglycerol Salen–CrIII Complexes
Authors: Keilitz Juliane , Haag Rainer
Published: May 2009

We present the synthesis of symmetrical (pyrrolidine‐salen)CrIII complexes immobilized on hyperbranched polyglycerol 1 through linkers of different lengths and their application in the asymmetric ring‐opening of meso‐epoxides. This reaction proceeded through a cooperative bimetallic mechanism and for the polymeric catalysts a positive dendritic effect with regard to the reaction rate was found. In addition, the introduction of long linkers (C6, C10, and C18) forced the favored head‐to‐tail orientation of two catalyst molecules and led to greater enantioselectivity with ee values of 48 % (cyclohexene oxide) and 64 % (cyclopentene oxide) for the ring‐opening of meso‐epoxides with TMSN3 catalyzed by hPG‐C10‐CrCl (13). The soluble polyglycerol‐supported catalyst was recovered five times by dialysis to afford similar activities and a 10 % increase in the enantioselectivity.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)