bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation of Hematopoietic Stem Cells from Mouse Embryonic Stem Cells
Authors: McKinney‐Freeman Shannon L. , Naveiras Olaia , Daley George Q.
Published: February 2008

This unit describes a protocol for the isolation of cells from murine embryonic stem cells with hematopoietic stem cell activity, defined by the ability to reconstitute, long term, multiple lineages of the hematopoietic system of lethally irradiated mice. The protocol subjects hematopoietic progenitors specified in differentiating embryoid bodies to ectopic HoxB4 expression (delivered via retroviral infection), followed by coculture and expansion on OP9 stromal cells in the presence of hematopoietic cytokines for 10 days. The protocol results in the generation of hundreds of millions of cells that can rescue mice from lethal irradiation. Although little is known about the phenotype and frequency of the actual hematopoietic stem cell–like cell within the population of cells generated by this protocol, the protocol establishes a system in which these cells can be further studied and the results ultimately translated to the human system. Curr. Protoc. Stem Cell Biol. 4:1F.3.1‐1F.3.10. © 2008 by John Wiley & Sons, Inc.
Atomic Force Microscopy (AFM)
Authors: Trache Andreea , Meininger Gerald A.
Published: February 2008

The atomic force microscope (AFM) is an important tool for studying biological samples due to its ability to image surfaces under liquids. The AFM operates by physical interaction of a cantilever tip with the molecules on the cell surface. Adhesion forces between the tip and cell surface molecules are detected as cantilever deflections. Thus, the cantilever tip can be used to image live cells with atomic resolution and to probe single molecular events in living cells under physiological conditions. Currently, this is the only technique available that directly provides structural, mechanical, and functional information at high resolution. This unit presents the basic AFM components, modes of operation, useful tips for sample preparation, and a short review of AFM applications in microbiology. Curr. Protoc. Microbiol. 8:2C.2.1‐2C.2.17. © 2008 by John Wiley & Sons, Inc.
Use of Potato Virus X (PVX)–Based Vectors for Gene Expression and Virus‐Induced Gene Silencing (VIGS)
Authors: Lacomme Christophe , Chapman Sean
Published: February 2008

Potato virus X–based vectors are a well established system for rapid in planta studies. The vectors can be used for expression of proteins in plants and to down‐regulate genes through virus‐induced gene silencing. The development of binary‐based vectors for Agrobacterium delivery makes this system well suited to high‐throughput studies. Protocols are given for establishing infections to achieve expression and VIGS through in vitro transcription and Agrobacterium delivery to glasshouse and in vitro–grown plant material. Curr. Protoc. Microbiol. 8:16I.1.1‐16I.1.13. © 2008 by John Wiley & Sons, Inc.
The XVth World Congress of Psychiatric Genetics, October 7–11, 2007: Rapporteur summaries of oral presentations
Authors: Alkelai Anna , Baum Amber , Carless Melanie , Crowley James , DasBanerjee Tania , Dempster Emma , Docherty Sophia , Hare Elizabeth , Galsworthy Michael J , Grover Deepak , Glubb Dylan , Karlsson Robert , Mill Jonathan , Sen Srijan , Quinones Marlon P. , Vallender Eric J. , Verma Ranjana , Vijayan Neetha.N. , Villafuerte Sandra , Voineskos Aristotle N. , Volk Heather , Yu Lan , Zimmermann Petra , DeLisi Lynn E.
Published: February 2008

The World Congress of Psychiatric Genetics (WCPG) has become an annual event since the early 1990's sponsored by the International Society of Psychiatric Genetics (ISPG). Each year the latest published and unpublished findings are aired for discussion by representatives of the majority of research programs on this topic world‐wide. The 2007 congress was held in New York City and attracted over 1000 researchers. The topics emphasized included results from whole genome association studies, the significance of copy number variation and the important contributions of epigenetic events to psychiatric disorders. There were over 20 oral sessions devoted to these and other topics of interest. Young investigator recipients of travel awards served as rapporteurs to summarize sessions and these summaries follow.
The preparation and characterization of fiber reinforced alginate hydrogel
Authors: Qin Yimin
Published: February 2008

To prepare fiber reinforced alginate hydrogels, calcium alginate fibers were mixed with aqueous sodium alginate solutions. Tests were carried out to assess the amount of calcium ions released from two types of alginate fibers, i.e., those made from alginate rich in guluronic acid (high G) and in mannuronic acid (high M), respectively. Experimental results showed that more calcium ions were released from the high M fibers and the hydrogel made from the high M fibers had a higher viscosity than that made from high G fibers. The water absorption and donating properties of these hydrogels were assessed by placing them in contact with gelatine gels. The results showed that alginate hydrogels with a high alginate content are capable of absorbing water from gelatine gels, while those with a high water content are able to donate water. When silver containing particles were mixed into the alginate solution, it was also possible to prepare fiber reinforced alginate hydrogel with antimicrobial properties. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Fish use of ecohydraulic‐based mesohabitat units in a low‐gradient Illinois stream: implications for stream restoration
Authors: Schwartz John S. , Herricks Edwin E.
Published: February 2008

A classification scheme for ecohydraulic‐based mesohabitat units was developed for a summer low‐flow period. Mesohabitat unit designations were based on the integration of three‐dimensional channel hydraulics, geomorphic maintenance processes of bed morphology, and biological resource needs of fish. Ecological relevance of the units was evaluated by a study of fish mesohabitat use patterns, and species relationships to feeding guild. By portraying the stream as a mosaic of hydraulic habitat patches that provide specific biotic resource needs, this study's aim was to advance how ecological information may be incorporated into the stream restoration design process.

Nine mesohabitat units were designated, including pool‐front, ‐mid, and ‐rear units, scour pool, simple and complex riffles, glide, submerged point bar, and channel expansion marginal deadwater. Physical habitat structure differed among the nine mesohabitat units by length, water depth, and bed slope and complexity. Fish were collected in specific unit volumes by use of prepositioned areal electrofishing devices, in which distinct patterns of fish mesohabitat use were observed.

A key finding was the differences in fish assemblages among the pool units, in which fish densities were greatest in the pool‐front and scour pool units. Also, fish density in the pool‐front unit was positively correlated with pool entrance slope. Biomass was greatest in the pool‐front and ‐mid units, and it was correlated with maximum mid‐pool depth. Density and biomass were generally lowest in the pool‐rear unit. Other unique relationships were also observed among the mesohabitat units.

Based on feeding guild, patterns of fish mesohabitat use were observed for this summer low‐flow period; insectivores dominantly used pool‐front and scour pool units, herbivores dominantly used complex riffle units, and piscivores used pool‐front and ‐mid units.

Useful ecological information was derived from fish species‐habitat relationships observed in this study, linking mesohabitat units with species requirements for food resources. Such findings support advancements to ecological design strategies for stream restoration that promote hydraulic habitat diversity.

Copyright © 2008 John Wiley & Sons, Ltd.
The Moray Firth Seal Management Plan: an adaptive framework for balancing the conservation of seals, salmon, fisheries and wildlife tourism in the UK
Authors: Butler James R.A. , Middlemas Stuart J. , McKelvey Simon A. , McMyn Iain , Leyshon Ben , Walker Ian , Thompson Paul M. , Boyd Ian L. , Duck Callan , Armstrong John D. , Graham Isla M. , Baxter John M.
Published: February 2008

Within the Moray Firth, north‐east Scotland, there is a history of conflict between seals and salmon fisheries. Under the UK's Conservation of Seals Act 1970 (CoSA) seals are shot to protect fisheries. In 1999 six rivers in the Moray Firth were designated as Special Areas of Conservation (SACs) for Atlantic salmon under the EU Habitats Directive, and in 2000 an SAC for harbour seals was designated in the Dornoch Firth.

In the 1990s salmon stocks declined. Fisheries managers believed the decline was partly caused by seal predation and consequently increased shooting effort. In years 1993–2003 Moray Firth harbour seal numbers declined possibly due to shooting, posing a potential threat to the status of the Dornoch Firth SAC. Meanwhile wildlife tourism based on marine mammals has increased. The declines in salmon and harbour seals, and the implementation of the Habitats Directive forced a watershed in the approach of statutory authorities to managing seals, salmon and tourism.

In years 2002–2005 local District Salmon Fishery Boards, the Scottish Executive, Scottish Natural Heritage and stakeholders negotiated a pilot Moray Firth Seal Management Plan to restore the favourable conservation status of seal and salmon SACs, and to reduce shooting of harbour seals and seal predation on salmon.

Key facets of the plan are the management of the Moray Firth region under a CoSA Conservation Order; application of the Potential Biological Removal concept to identify a limit of seals to be killed; management areas where removal of seals is targeted to protect salmon, while avoiding seal pupping and tourism sites; a training and reporting system for marksmen; a research programme, and a framework allowing an annual review of the plan.

The plan was introduced in April 2005. A maximum limit of 60 harbour and 70 grey seals was set. Forty‐six harbour and 33 grey seals were killed in 2005 while in 2006 these figures were 16 and 42 respectively. Although the numbers killed were below the maximum limits in both years the returns raised questions about the plan's ability to manage seal shooting at netting stations. The plan provides a useful adaptive co‐management framework for balancing seal and salmon conservation with the protection of fisheries and/or fish farms and tourism for application in the UK and internationally.

Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis and Local Anesthetic Activity of Some Novel N‐[5‐(4‐Substituted)phenyl‐1,3,4‐oxadiazol‐2‐yl]‐2‐(Substituted)‐Acetamides
Authors: Rajak Harish , Kharya Murli Dhar , Mishra Pradeep
Published: February 2008

A novel series of acetamides carrying substituted‐1,3,4‐oxadiazole moiety were synthesized from reaction of 5‐aryl‐2‐chloroacetamido‐1,3,4‐oxadiazoles with different secondary amines. The local anesthetic potential of the compounds was investigated using rabbit corneal reflex method and guinea pig's wheal derm method. The present work is the only one of its kind reporting local anesthetic activity in acetamide system combined with 1,3,4‐oxadiazole nucleus. Lidocaine was selected as standard drug in evaluation of local anesthetic activity of synthesized oxadiazole analogues. Compound 19 was found to possess significant local anesthetic activity in both the models employed for evaluation of local anesthetic activity. Compound 20, 23, 28, 29 and 35 also demonstrated marked local anesthetic activities. Structure‐activity relationships among synthesized compounds were also established.
3,4‐Disubstituted‐1,2,3,4,5,6,7,8‐octahydroquinazoline‐2‐thiones: Synthesis, Antimicrobial Evaluation and QSAR Investigations Using Hansch Analysis
Authors: Minu Maninder , Thangadurai Ananda , Wakode Sharad R. , Agrawal Shyam S. , Narasimhan Balasubramanian
Published: February 2008

The 3,4‐disubstituted‐1,2,3,4,5,6,7,8‐octahydroquinazoline‐2‐thione derivatives were synthesized and characterized by physicochemical and spectral means, and the results of antimicrobial study of these compounds against Staphylococcus aureus, Escherichia coli, and Candida albicans by tube dilution method indicated that 4‐(4‐chlorophenyl)‐3‐(4‐nitrophenylsulfonyl)‐1,2,3,4,5,6,7,8‐octahydroquinazoline‐2‐thione 6 and 4‐(4‐fluorophenyl)‐3‐(4‐nitrophenylsulfonyl)‐1,2,3,4,5,6,7,8‐octahydroquinazoline‐2‐thione 12 were the most potential ones. Further, the QSAR studies by Hansch analysis applied to find out the correlation between physicochemical characteristics of synthesized compounds with antimicrobial activity demonstrated the contribution of electronic parameter, total energy (Te) and the topological parameter (valence second order molecular connectivity index (2χv)). Excellent statistically significant models were developed by Hansch approach (r2 = 0.828–0.898) for the three microorganisms under study. The cross‐validated r2 (q2), which is an indication of the predictive capability of the model for all cases was also very good (q2 = 0.776–0.875).
Antimalarial Drugs – What is in Use and What is in the Pipeline
Authors: Schlitzer Martin
Published: February 2008

Malaria continues to be a potentially fatal threat to almost half of the world's population. In light of this threat, the armory to fight this disease is rather limited. Resistance against the most common and affordable antimalarials is widespread. Only few new drugs are in clinical development, most of them belong to long used classes of antimalarial drugs. This review will concisely cover the drugs which are currently in use, and describe the drug candidates which are in clinical evaluation.
Hinweise zu Wind‐, Schnee und Silolasten in DIN 1055
Authors: Fingerloos Frank , Timm Günter
Published: February 2008

Mit der bauaufsichtlichen Einführung der Normenteile 3, 4, 5, 6 und 9 der DIN 1055er‐Reihe: “Einwirkungen auf Tragwerke” wurden einige zusätzliche oder abweichende Regelungen zu den Normteilen DIN 1055‐4 und DIN 1055‐5 über die Musterliste der Technischen Baubestimmungen bekannt gemacht, die im Beitrag erläutert werden. Diese betreffen Windlasten für Reihenmittelhäuser und Vordächer, Schneeanhäufungen an Höhenversprüngen sowie die Schneelasten an Dachtraufen. Auf einige Änderungen in DIN 1055‐6 zu den Silolasten wird hingewiesen.
Lebensdauerbemessung. Baustein für die Instandsetzungsplanung am Beispiel eines Parkhauses
Authors: Lay Sascha , Rucker Petra , Brandes Christian , Käppler Joachim , Boese Robert
Published: February 2008

Am Beispiel eines Parkhauses wird gezeigt, wie durch die Kombination eines voll‐probabilistischen Modells zur Abschätzung der Wahrscheinlichkeit von Bewehrungskorrosion infolge Tausalzeintrag in Beton mit einer darauf abgestimmten Untersuchungsstrategie ein bedarfsgerechtes und daher kosteneffizientes Instandsetzungskonzept entwickelt werden kann.
Infraleichtbeton
Authors: Schlaich Mike , Zareef Mohamed El
Published: February 2008

Als Infraleichtbeton bezeichnen wir Beton, dessen spezifisches Gewicht unterhalb der von der Norm angegebenen Werte für gefügedichten Leichtbeton, also unterhalb 800 kg/m3, liegt. Die mit dem geringen Gewicht einhergehenden guten Wärmedämmeigenschaften erlauben es, monolithische Sichtbetonbauten ohne weitere Wärmedämmung – energiesparend und nachhaltig – zu errichten. Ein an der Technischen Universität Berlin entwickelter Infraleichtbeton und ein damit gebautes Wohnhaus werden hier vorgestellt.
Pregnane Glycosides from Caralluma adscendens var. fimbriata
Authors: Kunert Olaf , Rao Vijayalakshmi Gurunath , Babu Gummadi Sridhar , Sujatha Palatheeya , Sivagamy Malayalam , Anuradha Sandala , Rao Belvotagi Venkatrao Adavi , Kumar Bobbala Ravi , Alex Robert Michael , Schühly Wolfgang , Kühnelt Doris , Rao Ghanakota Venkateshwara , Rao Achanta Venkata Narasimha Appa
Published: February 2008

Eleven novel pregnane glycosides, 2–7 and 9–13, of which four, i.e., 10–13, comprised a new pregnane‐type genin exhibiting a hydroxymethylene instead of a Me group at C(19), and the known pregnane glycoside stalagmoside V (8) were isolated from whole plants of Caralluma adscendens var. fimbriata, a native Indian succulent plant. Their structures were elucidated by extensive 2D‐NMR spectroscopic studies.
Composition, and Anti‐Inflammatory and Antioxidant Activities of the Volatile Oil from the Fruit Peel of Garcinia brasiliensis
Authors: Martins Felipe T. , Doriguetto Antônio C. , de Souza Thiago C. , de Souza Kamila R. D. , dos Santos Marcelo H. , Moreira Maria E. C. , Barbosa Luiz C. A.
Published: February 2008

The composition of the volatile oil obtained by hydrodistillation from the fruit peel of Garcinia brasiliensis (Mart.) Planch. et Triana was determined by GC/MS. A total of 38 components were identified, including γ‐muurolene (10.3%), spathulenol (8.7%), δ‐cadinene (8.3%), torreyol (8.0%), α‐cadinol (7.0%), cadalene (6.3%), and γ‐cadinene (5.3%). Oxygenated sesquiterpenes (43%) were the main group of compounds. The anti‐inflammatory activity of the volatile oil was evaluated through the rat‐paw edema model induced by carrageenan. Inhibition of the inflammatory process was noticed 3 h after carrageenan administration. In addition, the volatile oil showed poor antioxidant activity.
Cytotoxic Alkaloids from the Bulbs of Fritillaria hupehensis
Authors: Zhang Yong‐Hui , Yang Xi‐Liang , Zhang Peng , Zhou Xue‐Feng , Ruan Han‐Li , Pi Hui‐Fang , Wu Ji‐Zhou , Sun Han‐Dong
Published: February 2008

Phytochemical investigation of the bulbs of Fritillaria hupehensis resulted in the isolation and structural elucidation of four new steroidal penta‐ and hexacyclic veratraman‐ and cevan‐based alkaloids, respectively, compounds 1–4. They were obtained together with the known constituents ebeinine (5) and zhebeinine (6), which were isolated for the first time from this plant. The structures of the new isolates were established by spectroscopic and mass‐spectrometric analyses, in combination with chemical methods. All compounds were assayed for their cytotoxic effects towards HeLa and HepG2 cell lines. Compounds 1 and 2 showed significant inhibitory effects against both types of tumor cells, with IC50 values in the range 2.52–0.23 μM, similar as those for 5‐fluorouracil used as positive control.
Synthesis and Antiproliferative Evaluation of 4‐Anilino‐n‐methoxyfuro[2,3‐b]quinoline Derivatives (n=6, 7). Part 5
Authors: Chen Yeh‐Long , Lin Huan‐Chin , Yang Chia‐Ning , Lu Pei‐Jung , Tzeng Cherng‐Chyi
Published: February 2008

A series of 27 differently substituted 4‐anilinofuro[2,3‐b]quinolines were synthesized and evaluated for their antiproliferative activities against the HeLa, SKHep1, SAS, AGS, A549, and CE81T cell lines, cancers commonly found in Asian countries. Among the compounds tested, 1‐{4‐[(3‐chloro‐7‐methoxyfuro[2,3‐b]quinolin‐4‐yl)amino]phenyl}ethanone (1) was the most potent, with IC50 values of 3.1, 3.0, and 4.2 μM, resp., against the growth of HeLa, SKHep, and CE81T cells. Compound 1 was, thus, further evaluated by flow cytometry to evaluate its effect on the cell‐cycle distribution of HeLa cells. Our results indicated that 1 readily induces cell‐cycle arrest in the G2/M phase, followed by DNA fragmentation and, ultimately, cell death.
An Unusual Metabolite of Cimicidol‐3‐O‐β‐D‐xyloside from Cimicifugae rhizoma by Rat Intestinal Bacteria
Authors: Li Jian‐Xin , Li Jun‐Feng , Chen Song‐Jie , Yu Zhi‐Yong
Published: February 2008

Cimicidol‐3‐O‐β‐D‐xyloside (1), one of the main components isolated from Cimicifugae rhizoma, is an active component with antiosteoporotic effect. The metabolism of 1 by rat intestinal bacteria was investigated, and two metabolites, 11β‐hydroxycimigenol (2) and foetidinol (3), were isolated and characterized by spectroscopic means including two‐dimensional NMR. Furthermore, the structures of six intermediates in the bacterial incubation were proposed on the basis of LC/MS analyses, and the possible metabolic pathway of the formation of 2, which passes through a unique sequence including hydrolysis, hydroxylation, and reduction, is discussed in detail.
Identification of Herbarium Whole‐Leaf Samples of Epilobium Species by ATR‐IR Spectroscopy
Authors: Strgulc Krajšek Simona , Buh Primož , Zega Anamarija , Kreft Samo
Published: February 2008

A simple, high‐accuracy FT‐IR method based on attenuated total reflection (ATR) was developed for the rapid determination of leaf samples of Epilobium species. The method is superior to other analytical techniques, since there is no need of laborious sample preparation such as grinding or extraction and solvent removal. A total of 70 herbarium specimens, belonging to all 13 Epilobium and to 2 Chamerion species growing in Slovenia, were analyzed. With the 100 most‐informative wavenumbers in the range 700–1800 cm−1, we obtained over 90% accuracy of species identification, with discriminant multivariate statistical analysis on the measurements made on whole dried leaves.
The First Potent Subtype‐Selective Retinoid X Receptor (RXR) Agonist Possessing a 3‐Isopropoxy‐4‐isopropylphenylamino Moiety, NEt‐3IP (RXRα/β‐dual agonist)
Authors: Takamatsu Kayo , Takano Atsushi , Yakushiji Nobumasa , Morohashi Kazunori , Morishita Ken‐ichi , Matsuura Nobuyasu , Makishima Makoto , Tai Akihiro , Sasaki Kenji , Kakuta Hiroki
Published: February 2008

Retinoid X receptor (RXR) agonists (rexinoids) are attracting much attention for their use in treatment of cancers, including tamoxifen‐resistant breast cancer and taxol‐resistant lung cancer, and metabolic disease. However, known RXR agonists have a highly lipophilic character. In addition, no subtype‐selective RXR agonists have been found. We previously reported an RXRα‐preferential agonist 4‐[N‐methanesulfonyl‐N‐(5,5,8,8‐tetramethyl‐5,6,7,8‐tetrahydro‐2‐naphthyl)amino]benzoic acid (6 a). The RXR agonistic activity is much less than that of well‐known RXR agonists. To develop potent, less‐lipophilic, and subtype‐selective RXR agonists, we created new RXR agonists possessing alkoxy and isopropyl groups as a lipophilic domain of the common structure of well‐known RXR agonists. As a result, compounds possessing branched alkoxy groups, 6‐[N‐ethyl‐N‐(3‐isopropoxy‐4‐isopropylphenyl)amino]nicotinic acid (NEt‐3IP: 7 a) and 6‐[N‐ethyl‐N‐(3‐isobutoxy‐4‐isopropylphenyl)amino]nicotinic acid (NEt‐3IB: 7 c), showed RXR agonistic activity as potent as, or more potent than, the activities of representative RXR agonists. Moreover, NEt‐3IP (7 a) was found to be the first RXRα/β‐selective (or RXRα/β‐dual) agonist. Being potent, less lipophilic, and having RXR subtype‐selective activity, NEt‐3IP (7 a) is expected to become a new drug candidate and to be a useful biological tool for clarifying each RXR subtype function.
Colour matching experiments with RGB‐LEDs
Authors: Csuti P. , Schanda J.
Published: February 2008

CIE colorimetry breaks down when lights produced by narrow band RGB‐LEDs are matched with broad‐band lights. A colour matching experiment was set up and matches in a number of parts of the chromaticity diagram have been made, to determine the magnitude of the discrepancy. Differences between visual and instrumental matches increase as one moves in the chromaticity diagram from yellowish white lights toward greenish and bluish lights.

CIE TC 1‐36 recently suggested newly defined cone fundamentals: Applying a transformation of these to a space similar to the CIE XYZ space enables a much better prediction of the matches to be made. The difference between the visual match and its instrumental prediction decreases by a factor of two or even more.

The use of a cone fundamental based colorimetric system is recommended for LED colorimetry. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 108–112, 2008
An integrated color‐appearance model using CIELUV and its applications
Authors: Nayatani Yoshinobu , Sakai Hideki
Published: February 2008

A new type of color‐appearance model is presented together with its formulations. It is named In‐CAM(CIELUV), which means the integrated color‐appearance model using CIELUV space. Using the In‐CAM(CIELUV), we can integrate its fields of applications in both colorimetric engineering and artistic color design. Various applications are introduced in colorimetric and color design fields. The In‐CAM(CIELUV) connects directly colorimetric color space and perceptual Hue‐Tone color order systems. In other words, the In‐CAM (CIELUV) gives a colorimetric basis for Hue‐Tone system. The three color attributes in the In‐CAM(CIELUV) space are mutually independent. This is a very convenient feature for selecting color combinations. Some two‐color combinations selected systematically in the In‐CAM(CIELUV) space are shown. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 125–134, 2008
Uncertainty analysis for the NIST 0:45 Reflectometer
Authors: Early Edward A. , Nadal Maria E.
Published: February 2008

Sets of color tiles are available from the National Institute of Standards and Technology calibrated using the NIST 0:45 Reflectometer. The uncertainties associated with the measured values for the color tiles are an indispensable component of the calibration report that accompanies these tiles. A systematic, analytical approach developed previously was applied to the particular case of the reference instrument and color tile set, taking into account the operation and characteristics of the instrument and the spectral properties of the set. The primary sources of uncertainty were identified, and the resulting uncertainties in the color space values L*, a*, and b* were determined. In general, the uncertainties are lowest for those color tiles whose reflectance factors are nearly constant with wavelength. Published in 2008 by John Wiley & Sons, Inc. Col Res Appl, 33, 100–107, 2008
Unbinding Molecular Recognition Force Maps of Localized Single Receptor Molecules by Atomic Force Microscopy
Authors: Sotres Javier , Lostao Anabel , Wildling Linda , Ebner Andreas , Gómez‐Moreno Carlos , Gruber Hermann J. , Hinterdorfer Peter , Baró Arturo M.
Published: February 2008

Atomic force microscopy is a technique capable to study biological recognition processes at the single‐molecule level. In this work we operate the AFM in a force‐scan based mode, the jumping mode, where simultaneous topographic and tip–sample adhesion maps are acquired. This approach obtains the unbinding force between a well‐defined receptor molecule and a ligand attached to the AFM tip. The method is applied to the avidin–biotin system. In contrast with previous data, we obtain laterally resolved adhesion maps of avidin–biotin unbinding forces highly correlated with single avidin molecules in the corresponding topographic map. The scanning rate 250 pixel s−1 (2 min for a 128×128 image) is limited by the hydrodynamic drag force. We are able to build a rupture‐force distribution histogram that corresponds to a single defined molecule. Furthermore, we find that due to the motility of the polymer used as spacer to anchor the ligand to the tip, its direction at rupture does not generally coincide with the normal to the tip–sample, this introduces an appreciable error in the measured force.
Kinin‐B2 receptor expression and activity during differentiation of embryonic rat neurospheres
Authors: Martins Antonio H. , Alves Janaína M. , Trujillo Cleber A. , Schwindt Telma T. , Barnabé Gabriela F. , Motta Fabiana L. T. , Guimaraes Alessander O. , Casarini Dulce E. , Mello Luiz E. , Pesquero João B. , Ulrich Henning
Published: February 2008

Neural progenitor cells were isolated from rat fetal telencephalon and proliferate as neurospheres in the presence of EGF, FGF‐2, and heparin. In the absence of these growth factors, neurospheres differentiate into neurons, astrocytes, and oligodendrocytes. Using an embryonal carcinoma cell line as in vitro differentiation model, we have already demonstrated the presence of an autocrine loop system between kinin‐B2 receptor activity and secretion of its ligand bradykinin (BK) as prerequisites for final neuronal differentiation (Martins et al., J Biol Chem 2005; 280: 19576–19586). The aim of this study was to verify the activity of the kallikrein‐kinin system (KKS) during neural progenitor cell differentiation. Immunofluorescence studies and flow cytometry analysis revealed increases in glial fibrillary acidic protein and β‐3 tubulin expression and decrease in the number of nestin‐positive cells along neurospheres differentiation, indicating the transition of neural progenitor cells to astrocytes and neurons. Kinin‐B2 receptor expression and activity, secretion of BK into the medium, and presence of high‐molecular weight kininogen suggest the participation of the KKS in neurosphere differentiation. Functional kinin‐B2 receptors and BK secretion indicate an autocrine loop during neurosphere differentiation to neurons, astrocytes, and oligodendrocytes, reflecting events occurring during early brain development. © 2008 International Society for Analytical Cytology
Iron and Cobalt Complexes of 4‐Alkyl‐2,6‐diiminopyridine Ligands: Synthesis and Ethylene Polymerization Catalysis
Authors: Cámpora Juan , Naz A. Marcos , Palma Pilar , Rodríguez‐Delgado Antonio , Álvarez Eleuterio , Tritto Incoronata , Boggioni Laura
Published: February 2008

A new methodology for selective alkylation of the 2,6‐diiminopyridine (pdi) ligands allows the ready synthesis of new derivatives displaying 2‐methyl‐2‐phenylpropyl (neophyl), benzyl, or allyl groups in the 4‐position of the pyridine ring. A set of Fe and Co complexes containing the new ligands have been synthesized and fully characterized. The presence of 4‐neophyl or ‐benzyl groups does not perturb the performance of the complexes as ethylene polymerization catalysts, but the introduction of the 4‐allyl group leads to the production of higher molecular weight polymers. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Platinum(II) Complexes with the Diethyl Aminomethylphosphonate Ligand (amp): Characterization, Properties, and Unusual Solution Behavior
Authors: Cornacchia Daniele , Cerasino Leonardo , Pacifico Concetta , Natile Giovanni
Published: February 2008

Cisplatin is one of the most widely prescribed drugs for the treatment of solid tumors, even though its pharmacological potential is often limited by side effects (nephrotoxicity, neurotoxicity, alopecia) and a limited spectrum of activity. Overcoming these limitations is one of the most chased goals by researchers in the field of medicinal chemistry. Since phosphonates have a great selectivity for bone tissues, we have extended a previous study on a platinum(II) complex with a diethyl [(methylsulfinyl)methyl]phosphonate (smp) ligand, [PtCl2(S,O‐smp)], to another phosphonate ester ligand, diethyl aminomethylphosphonate (amp). Further interest in this investigation was generated by the observation that [PtCl2(S,O‐smp)] was capable of inhibiting matrix metalloproteinases (MMPs), which also play a role in tumor growth. The interaction of the amp ligand with the tetrachloroplatinate(II) anion resulted in the production of the mono‐ and bis(amp) adducts in which the ligand acts as a monodentate N‐coordinated species; however, no stable species with the chelating ligand could be isolated. A rationale for the different chelating abilities of amp and smp is offered. A solution of cis‐[PtCl2(N‐amp)2] in organic solvents is very stable if kept in the dark; if it is exposed to light, it undergoes a ready and clean cis/trans isomerization, affording the trans‐[PtCl2(N‐amp)2] complex. The compounds have been characterized by means of spectroscopic techniques (1H, 31P, and 195Pt NMR), ESI‐MS, and elemental analysis. In the case of trans‐[PtCl2(N‐amp)2], the X‐ray structure has revealed a peculiar in‐plane orientation of the amp ligand. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Lewis Acid Catalyzed Intermolecular Olefin Hydroamination: Scope, Limitation, and Mechanism
Authors: Cheng Xiaojuan , Xia Yuanzhi , Wei Hua , Xu Bin , Zhang Chongguang , Li Yahong , Qian Guimin , Zhang Xiaohua , Li Kai , Li Wu
Published: February 2008

Intermolecular olefin hydroamination was studied by various Lewis acids. The results of ZrCl4, FeCl3, BiCl3, and AlCl3 catalyzed reactions of norbornene with aromatic amines were compared, and BiCl3 was found to be the most effective catalyst to give high yields for various amines, whereas ZrCl4 could promote the reactions at relatively low temperatures. The FeCl3 catalyzed reactions were the most chemoselective and excellent yields could be achieved for certain amines by using AlCl3. A carbocation mechanism was proposed, and the controllable syntheses of allylamine and tetrahydroquinoline from isoprene and 2,5‐dichloroaniline were achieved by application of this mechanism. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
A Convenient Synthesis of Furanose‐Free D‐Fucose Per‐O‐Acetates and a Precursor for Anthrose
Authors: Hou Shujie , Kováč Pavol
Published: February 2008

Methyl 3,4‐O‐isopropylidene‐α‐ or β‐D‐galactopyranoside was iodinated with triiodoimidazole in the presence of triphenylphosphane and the corresponding 6‐deoxy‐6‐iodo derivatives 5 or 6, respectively, were converted to furanose‐free 1,2,3,4‐tetra‐O‐acetyl‐α,β‐D‐fucopyranose. A key intermediate for chemical synthesis of anthrose, a constituent of the tetrasaccharide of major glycoprotein of Bacillus anthracis exosporium, 1‐O‐acetyl‐4‐azido‐2‐O‐benzoyl‐3‐O‐benzyl‐4,6‐dideoxy‐α,β‐D‐glucopyranose, was synthesized from 5 or 6 in 7 steps. The latter was readily converted into the corresponding 1‐O‐trichloroacetimidate.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Palladium‐Catalysed Cross‐Coupling Reactions of Triorganoindium Reagents with Alkenyl Halides
Authors: Riveiros Ricardo , Saya Lucía , Pérez Sestelo José , Sarandeses Luis A.
Published: February 2008

The regio‐ and stereoselectivity of the palladium‐catalysed cross‐coupling reactions of indium organometallics withstereodefined 1‐haloalkenes and 1,1‐dihaloalkenes have been studied. Triorganoindium reagents (R3In; R = alkyl, alkenyl, aryl and alkynyl) can be stereospecifically coupled with stereodefined alkenyl iodides in good yields and short reaction times under palladium catalysis. Additionally, the palladium‐catalysed cross‐coupling reaction of R3In (90 mol‐%) with 1,1‐dibromo‐1‐alkenes gave dicoupling products in high yields. When the reaction was performed with 40 mol‐% of aryl‐, vinyl‐ and alkynylindium derivatives, trans‐selective monosubstitution products were obtained in moderate to good yields. These selective couplings were performed with [Pd2dba3]/P(2‐furyl)3 (1:1, 2 mol‐%) at 0 °C or, for 1,1‐dibromo‐1‐alkenes with an aromatic group in the β‐position, [Pd(DPEPhos)Cl2] (2 mol‐%) at room temperature as the catalytic system. The resulting (Z)‐monobromoalkenes can be further functionalized by cross‐coupling reaction with various R3In (R = alkyl, aryl and alkynyl) in the presence of [Pd(tBu3P)2] as catalyst, at room temperature, to provide trisubstituted olefins in good yields.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Long‐chained gemini surfactants for semipermanent wall coatings in capillary electrophoresis of proteins
Authors: Liu Qian , Yuan Jinbin , Li Yanqing , Yao Shouzhuo
Published: February 2008

In this paper, we presented the first example of using gemini surfactants as semipermanent coatings in CE for protein separation. These coatings are based on the self‐assembly of a series of cationic gemini surfactants, alkanediyl‐α,ω‐bis(dimethylalkylammonium bromide) (m‐s‐m), on the capillary wall. The coatings can keep stable for a long time without surfactant in the buffer, e.g., after the surfactants were removed from the buffer, the reversed EOF only decreased by 3.6 and 3.9% for 18‐2‐18 and 16‐2‐16 coatings over 60 min under continuous electrophoretic conditions. The coating stability increased with the alkyl chain length m. The double long chains of geminis (m ≥ 14) yielded a good coating stability; meanwhile, the spacer group acted as an EOF modifier. Thus, this bifunctional surfactant coating provided a new buffer‐independent method for EOF control. For 18‐s‐18 series, the best coating stability and largest EOF were obtained at s = 10. Ranging s from 3 to 10 yielded a linear fine‐tuning of EOF and thereby allowed the adjustment of the protein apparent mobility. Highly efficient separation (>500 000 plates/m) was achieved with all the 18‐s‐18 coatings. Excellent run‐to‐run and day‐to‐day reproducibility (RSD of migration time ≤0.7 and 4.3% for run‐to‐run and day‐to‐day assays, respectively) and fine recoveries (97.5–100.1%) of the protein samples indicated that the gemini semipermanent coatings were quite effective for the wall adsorption suppression of proteins.
Cationic surfactants for micellar electrokinetic chromatography: 2. Representative applications to acidic, basic, and hydrophobic analytes
Authors: Schnee Vincent P. , Palmer Christopher P.
Published: February 2008

Changes in MEKC chemical selectivity that are induced by changes in the headgroup structure of cationic surfactants are examined. Separations of acidic, basic, and hydrophobic solutes are examined. The acidic analytes are comprised of methoxyphenols, which are of interest due to their prevalence in wood smoke. The basic solutes consist of compounds often found in forensic urine analysis, and represent typical basic pharmaceuticals. The hydrophobic solutes are six pharmaceutical corticosteroids used in replacement therapy of adrenocortical insufficiency and nonspecific treatment of inflammatory and allergic conditions. The role of the headgroup was found to be quite significant when analyzing acidic compounds with not all the surfactants being able to resolve all of the analytes. The headgroup also induced migration order switches among the acidic analytes. All of the surfactants examined here in were found to be suitable for the analysis of basic analytes with each surfactant providing unique selectivity. The hydrophobic solutes were separated best with the larger more hydrophobic surfactant headgroups. The steroid separation with these two surfactants was achieved without the use of organic modifiers or a mixed micellar phase.
Determination of Acetic Acid in Fermentation Broth by Gas‐Diffusion Technique
Authors: Tippkötter N. , Deterding A. , Ulber R.
Published: February 2008

Due to the interfering effects of acetic acid in many fermentation processes, a gas‐diffusion technique was developed for the online determination of acetic acid. The measurements were accomplished with a flow diffusion analysis (FDA) unit from the TRACE Analytics GmbH, Braunschweig, Germany. The diffusion analysis is based on the UV‐absorbance of acetic acid at 205 nm. The measurement was achieved by the separation of an acceptor and a carrier stream (acidified fermentation broth) using a gas permeable polytetrafluoroethylene (PTFE) membrane, whereby broth constituents that would otherwise disturb the UV‐measurement of acetic acid, are held back efficiently. Merely, the fermentation by‐products, e.g. formic acid, is capable of diffusing through the membrane. While formic acid can disturb the measurement, carbon dioxide does not absorb at 205 nm. The method operates with time‐dependent sample enrichment. During the analysis, a small volume of the acceptor stream is stopped for a defined time interval in the acceptor chamber. During this period, the gaseous acetic acid diffuses through the membrane and is enriched in the acceptor chamber. Subsequently after the enrichment, the acceptor stream flows through a UV‐detector. The intensity of the signal is proportional to the acetic acid concentration. Online measurements in bioreactors via a sterile filtration probe have been accomplished. A linear calibration in the range of 0.5–5.0 g/L acetic acid with a relative standard deviation of <5 % was obtained. A sampling rate of 8 samples per hour was possible. The system was applied for the determination of acetic acid in E. coli fermentation broth. The instrument is easy to clean, very user‐friendly and does not require any toxic or expensive reagents.
Statistical and biological definitions of “anatomically modern” humans: Suggestions for a unified approach to modern morphology
Authors: Pearson Osbjorn M.
Published: February 2008

Much of the recent literature on the origin of modern humans has been plagued by an inability of the participants in the debate to agree on what constitutes “anatomically modern” morphology. An upshot of this disagreement has been an ongoing set of debates over which specimens are or are not anatomically modern and whether various fossil specimens such as the Florisbad cranium, Vindija Neanderthals, Klasies River Mouth mandibles, or Skhul‐Qafzeh hominins, all of which arguably possess some supposedly “modern” traits, qualify as genuinely “modern.” Such decisions frequently have implications with regard to how we reconstruct later hominin phylogenies and, ultimately, how we reconstruct the behaviors, adaptations, and evolution of Middle‐Late Pleistocene African hominins and their contemporaries.
The origin of modern anatomy: By speciation or intraspecific evolution?
Authors: Bräuer Günter
Published: February 2008

“Speciation remains the special case, the less frequent and more elusive phenomenon, often arising by default” (p 164).1

Over the last thirty years, great progress has been made regarding our understanding ofHomo sapiensevolution in Africa and, in particular, the origin of anatomically modern humans. However, in the mid‐1970s, the whole process ofHomo sapiensevolution in Africa was unclear and confusing. At that time it was widely assumed that very archaic‐looking hominins, also called the “Rhodesioids,” which included the specimens from Kabwe (Zambia), Saldanha (South Africa), and Eyasi (Tanzania), were spread over wide parts of the continent as recently as 30,000 or 40,000 years ago. Yet, at the same time, there were also indications from the Omo Kibish skeletal remains (Ethiopia) and the Border Cave specimens (South Africa) that anatomically modern humans had already been present somewhat earlier than 100,000 years B.P.2,3Thus, it was puzzling how such early moderns could fit in with the presence of very archaic humans still existing in Eastern and Southern Africa only 30,000 years ago.
Homo in the middle pleistocene: Hypodigms, variation, and species recognition
Authors: Rightmire G. Philip
Published: February 2008

It is generally accepted that modern humans evolved in Africa. This consensus has emerged in the last two decades, as molecular evidence has been coupled with findings from paleontology and prehistory. Patterns of DNA variation in living populations, morphology of fossils, and archeological traces can all be read to show that our species has deep roots in Africa and began to disperse into other regions only late in the Pleistocene. There are still questions about the timing of these dispersals and the extent to which modern people replaced or exchanged genes with other, more archaic groups, but new problems are now coming more clearly into focus. These relate to the ancestry of Homo sapiens in the Middle Pleistocene. In this essay, I emphasize the evidence available from Middle Pleistocene localities in Africa and Europe, exploring variation among individuals, composition of hypodigms, species‐level taxonomy, and evolutionary relationships of the hominin populations. One obvious difficulty is that the fossils are scarce. For the most part, only incomplete crania are available from African localities. The record is more comprehensive for the Sima de los Huesos in Spain, but principally crania and jaws are known from other European sites. This means that skull traits and measurements must provide the basis for sorting individuals to groups and building differential diagnoses. For much of the material, dating is still poorly controlled, although a few of the most important assemblages can now be placed more securely within a Middle Pleistocene chronological framework. Despite these constraints, it is possible to point toward tentative solutions.
Unusual Loss of Substituents in the Course of Cyclization of Tetrahydrobilines to Dihydroporphyrins
Authors: Damke Jan‐Erik , Latos‐Grażyński Lechosław , Montforts Franz‐Peter
Published: February 2008

Metallo‐tetrahydrobiline rac‐8 was prepared to investigate its cyclization directed to the formation of N‐confused chlorins. To achieve the site‐directed selectivity of the cyclization, the 2‐position of rac‐2 was activated by an electron‐withdrawing cyano function and its 1‐position was blocked by a methyl group. In spite of this provision, the cyclization occurred at the apparently blocked 1‐position with loss or migration of the methyl substituent.
Synthesis of 3‐Aminotropones from N‐Boc‐Protected Furan‐2‐amine (=tert‐Butyl Furan‐2‐ylcarbamate; Boc=(tert‐Butoxy)carbonyl) by Cycloaddition Reactions and Subsequent Rearrangement
Authors: Montaña Ángel M. , Barcia Juan A. , Kociok‐Köhn Gabriele , Font‐Bardia Mercè , Solans Xavier
Published: February 2008

The 3‐aminotropones (=3‐aminocyclohepta‐2,4,6‐trien‐1‐ones) 4 were prepared in two steps by i) a [4+3] cycloaddition reaction between a conveniently substituted α,α′‐dihalo ketone 1 and a furan‐2‐amine derivative 2 functionalized at C(2) by a protected amino group (→3), and ii) a base‐induced molecular rearrangement of the cycloadduct 3 via cleavage of the O‐bridge. A mechanism for the formation of 3‐aminotropones is proposed on the basis of the initial deprotonation of the [(tert‐butoxy)carbonyl]amino (BocNH) group of 3, followed by O‐bridge opening, an acid–base equilibrium, and finally an alkoxyaluminate elimination to afford the conjugated stable troponoid system (Scheme 7).
Selenium‐Containing Heterocycles from Isoselenocyanates: 4‐Methylselenazole Derivatives from the Reaction with Malononitrile and Propargyl Chloride
Authors: Sommen Geoffroy L. , Linden Anthony , Heimgartner Heinz
Published: February 2008

Aryl isoselenocyanates 1 react with malononitrile (6a) and propargyl chloride (8) in DMF in the presence of Et3N to give the corresponding 2‐(3‐aryl‐2,3‐dihydro‐4‐methyl‐1,3‐selenazol‐2‐ylidene)malononitriles 12 as major products. The analogous reaction takes place with benzoylacetonitrile (6f) instead of 6a. In some cases, the corresponding noncyclic 2‐[(arylamino)(prop‐2‐ynylselanyl)methylidene]malononitriles 9 were obtained as minor products. The structures of 9e and 11a have been established by X‐ray crystallography.
Heteroclitins N – Q, New Compounds from Stems of Kadsura heteroclita (Roxb.) Craib
Authors: Xu Li‐Jia , Liu Hai‐Tao , Peng Yong , Chen Si‐Bao , Chen Shi‐Lin , Xiao Pei‐Gen
Published: February 2008

From the stems of Kadsura heteroclita (Roxb.) Craib, a new novel C19 homolignan, heteroclitin N (1), as well as three new lignans, heteroclitins OQ (2–4), were isolated. Their structures were elucidated based on spectral analysis, including 1D and 2D NMR experiments. There is an additional spirocyclic oxirane system in heteroclitin O (2), which is the first example of a lignan with an oxirane ring in a spirobenzofuranoid dibenzocyclooctene structure in the genus Kadsura.
Synthesis of Optically Active 1‐(1‐Phenylethyl)‐1H‐imidazoles Derived from 1‐Phenylethylamine
Authors: Mlostoń Grzegorz , Mucha Paulina , Urbaniak Katarzyna , Broda Karolina , Heimgartner Heinz
Published: February 2008

The three‐component reaction of (R)‐ or (S)‐1‐phenylethylamine (6), formaldehyde, and an α‐(hydroxyimino) ketone 5, i.e., 3‐(hydroxyimino)butan‐2‐one (5a) or 2‐(hydroxyimino)‐1,2‐diphenylethanone (5b), yields the corresponding enantiomerically pure 1‐(1‐phenylethyl)‐1H‐imidazole 3‐oxide 7 in high yield (Schemes 2 and 3). The reactions are carried out either in MeOH or in AcOH. Smooth transformations of the N‐oxides into optically active 1‐(1‐phenylethyl)‐1H‐imidazoles 10 and 2,3‐dihydro‐1‐(1‐phenylethyl)‐1H‐imidazole‐2‐thiones 11 are achieved by treatment of 7 with Raney‐Ni and 2,2,4,4‐tetramethyl‐3‐thioxocyclobutanone (12), respectively (Scheme 4).
Three New Monoterpenoid Indole Alkaloids from Ervatamia flabelliformis
Authors: Liang Shuang , Chen Hai‐Sheng , Shen Yun‐Heng , Zhang Wei‐Dong , Jin Yong‐Sheng , Liu Run‐Hui
Published: February 2008

The three new monoterpenoid indole alkaloids 1–3 were isolated from the stems of Ervatamia flabelliformis. The structures were elucidated on the basis of spectral analysis and chemical derivatization.