bluuebunny/crossref_metadata_2025 huggingface dataset:
Human Chorionic Gonadotropin as a Central Regulator of Pregnancy Immune Tolerance
Authors: Schumacher Anne , Heinze Kristina , Witte Jeanette , Poloski Eileen , Linzke Nadja , Woidacki Katja , Zenclussen Ana C.
Published: February 2013

Normal pregnancy is characterized by an early expansion of regulatory T cells (Tregs), which is known to contribute to fetal tolerance. However, mechanisms and factors behind Treg expansion are not yet defined. Recently, we proposed that the pregnancy hormone human chorionic gonadotropin (hCG) efficiently attracts human Tregs to trophoblasts, favoring their accumulation locally. In this study, we hypothesized that hCG not only acts as a chemoattractant of Tregs but also plays a central role in pregnancy-induced immune tolerance. Virgin, normal pregnant, and abortion-prone female mice were treated either with 10 IU/ml hCG or PBS at days 0, 2, 4, and 6 of pregnancy. The hCG effect on Treg frequency and cytokine secretion was determined in Foxp3gfp females. hCG impact on Treg suppressive capacity was studied in vitro. In vivo, we investigated whether hCG enhances Treg suppressive capacity indirectly by modulating dendritic cell maturation in an established mouse model of disturbed fetal tolerance. Application of hCG increased Treg frequency in vivo and their suppressive activity in vitro. In females having spontaneous abortions, hCG provoked not only an augmentation of Treg numbers, but also normalized fetal abortion rates. hCG-generated Tregs were fully functional and could confer tolerance when adoptively transferred. hCG also retained dendritic cells in a tolerogenic state that is likely to contribute to both Treg expansion and prevention of abortion. Our results position hCG in a novel, so far unknown role as modulator of immune tolerance during pregnancy.
IL-10 Inhibits Mature Fibrotic Granuloma Formation during Mycobacterium tuberculosis Infection
Authors: Cyktor Joshua C. , Carruthers Bridget , Kominsky Rachel A. , Beamer Gillian L. , Stromberg Paul , Turner Joanne
Published: February 2013

Protective immunity and latent Mycobacterium tuberculosis infection in humans are associated with the formation of mature protective granulomas within the lung. Unfortunately, understanding the importance of such structures has been hindered by the lack of small-animal models that can develop mature granulomas. In this article, we describe for the first time, to our knowledge, the formation of mature, fibrotic M. tuberculosis–containing pulmonary granulomas in a mouse model of IL-10 deficiency (CBA/J IL-10−/−). Long-term control of M. tuberculosis infection in the absence of IL-10 was also associated with an early and enhanced capacity for Ag presentation and a significant increase in the generation of multifunctional T cells. Although IL-10 deficiency is known to enhance Th1 immune responses in general, we demonstrate in this study using transient anti–IL-10R treatment that it is the presence of IL-10 in vivo during the first month of M. tuberculosis infection that plays a definitive role in the inhibition of optimum protective immunity that can establish the environment for mature granuloma formation. Although the importance of IL-10 during M. tuberculosis infection has been debated, our data demonstrate that in CBA/J mice, IL-10 plays a significant early inhibitory role in preventing the development of protective immunity associated with containment of M. tuberculosis infection.
The Structural Wedge Domain of the Receptor-like Tyrosine Phosphatase CD45 Enforces B Cell Tolerance by Regulating Substrate Specificity
Authors: Zikherman Julie , Parameswaran Ramya , Hermiston Michelle , Weiss Arthur
Published: February 2013

CD45 is a receptor-like tyrosine phosphatase that positively regulates BCR signaling by dephosphorylating the inhibitory tyrosine of the Src family kinases. We showed previously that a single point mutation, E613R, introduced into the cytoplasmic membrane–proximal “wedge” domain of CD45 is sufficient to drive a lupus-like autoimmune disease on a susceptible genetic background. To clarify the molecular mechanism of this disease, we took advantage of a unique allelic series of mice in which the expression of CD45 is varied across a broad range. Although both E613R B cells and those with supraphysiologic CD45 expression exhibited hyperresponsive BCR signaling, they did so by opposite regulation of the Src family kinase Lyn. We demonstrated that the E613R allele of CD45 does not function as a hyper- or hypomorphic allele but rather alters the substrate specificity of CD45 for Lyn. Despite similarly enhancing BCR signaling, only B cells with supraphysiologic CD45 expression became anergic, whereas only mice harboring the E613R mutation developed frank autoimmunity on a susceptible genetic background. We showed that selective impairment of a Lyn-dependent negative-regulatory circuit in E613R B cells drove autoimmunity in E613R mice. This demonstrates that relaxing negative regulation of BCR signaling, rather than enhancing positive regulation, is critical for driving autoimmunity in this system.
Sustainable Corporate Entrepreneurship from a Strategic Corporate Social Responsibility Perspective
Authors: Atiq Muhammad , Karatas-Ozkan Mine
Published: February 2013

This paper explores the process of sustainable entrepreneurship from the perspective of strategic corporate social responsibility (CSR). Drawing on insights from entrepreneurship studies that focus on opportunity creation and enactment, along with the extant literature on CSR, the authors propose a conceptual framework for sustainable entrepreneurship that combines an entrepreneurial approach with sustainability. The authors suggest that sustainability should be embedded in the business operations of companies and that sustainable business practices should be driven by an entrepreneurial approach in order to create shared value – that is, value for the business as well as for society. Shared value creation is the outcome of sustainable corporate entrepreneurship.
Characterizing High-Growth Firms in New Zealand
Authors: Hinton Mark , Hamilton R.T.
Published: February 2013

This study characterizes high-growth New Zealand-owned firms operating in business-to-business relationships. Within a case study design featuring six such firms, four dimensions emerged that captured their key features: founders' characteristics; opportunity orientation; opportunity exploitation; and the management of growth. All the firms had joint founders who brought complementary skills and maintained external advice networks. The growth opportunities leveraged innovations of other firms. Exploitation was in niche areas in which there were both few competitors and small numbers of larger customers, facilitating intensive relationship marketing. The founders managed the businesses by developing a pro-growth culture among employees, but supported this through strong financial control systems and low debt preference. The lack of evidence on the characteristics of this important group of firms has contributed to poorly targeted policy. This paper begins to redress this situation.
Influence of Entrepreneurial Teams on the Growth Orientation of Early-Stage High-Tech SMEs in China
Authors: Xiao Li , Larson Mitch , North David
Published: February 2013

This paper examines the growth-orientation effects of specific entrepreneurial expertise in an emerging economy. It draws on face-to-face interviews with entrepreneurs of young high-tech small and medium-sized enterprises in the Chinese provinces of Guangdong and Guangxi. Using four measures of firm-level performance – that is, employment, profitability, sales turnover and internationalization – the findings show that different types of entrepreneurial teams have different growth intentions depending on the strengths of the team members. The ‘mixed’ type of team optimized performance in general and employment growth in particular, while ‘technology entrepreneurial’ teams were more profit-oriented, and ‘business practice entrepreneurial’ teams were more export-oriented.
In Situ Measurement of Vapor Uptake in the Rodent Upper Respiratory Tract
Authors: Morris John B. , Cichocki Joseph A. , Smith Gregory J.
Published: February 2013

The response of respiratory tract tissue target sites to inhaled vapors depends on the amount of inhaled vapor that is delivered to those sites. Direct measurement of vapor absorption within a specific airway of the living animal requires that the airway be isolated, which currently can only be performed on the upper airways. Towards this end, the upper respiratory tract (all airways anterior to the larynx) is surgically isolated in the anesthetized rat by tracheostomy and insertion of two endotracheal tubes, one leading anteriorly and the other posteriorly. The surgically manipulated animal is then placed in a nose‐only inhalation chamber and test‐vapor‐laden air is drawn through the isolated upper airways under defined air flow conditions via the anterior endotracheal tube. The animal spontaneously respires clean air into the lungs during this procedure via the posterior endotracheal tube. The concentration of test vapor in air entering and the air exiting the upper airways is measured by gas chromatography, and the difference in concentrations provides a measure of vapor absorption in that site. A rich database is available on upper respiratory tract vapor absorption as measured by this methodology, to which newly obtained data can be compared. These data have been instrumental not only in understanding the regional airway toxicity of inspired vapors, but also for developing mathematical models to describe inhaled vapor dosimetry. Curr. Protoc. Toxicol. 55:24.1.1‐24.1.10. © 2013 by John Wiley & Sons, Inc.
In Vitro Enrichment of Tumor‐Initiating Cells from Human Established Cell Lines
Authors: Benayoun Liat , Shaked Yuval
Published: February 2013

This unit describes protocols for culturing and subsequently enriching cancer stem cells (CSCs), also referred to as tumor‐initiating cells (TICs), from human established cell lines. TICs are thought to display the major cell population in the tumor with the proliferative capacity to seed tumors, implying that theyare critical in initiating and driving tumorigenesis. The protocols show the methods for enriching and subsequently characterizing TIC populations from a series of human tumors including glioblastoma, breast, and pancreatic tumors. Protocols evaluating the morphology, phenotypic, and functional properties of TICs are described. Long‐term cultures grown either as monolayers (“TIC‐low”) or as non‐adherent tumor spheres (“TIC‐high”) are generated. As a result, cells from the TIC‐high culture exhibit increased expression of stem cell surface markers, such as CD133, CD44, and CD24, high aldehyde dehydrogenase (ALDH) activity, and elevated expression levels of p21, in comparison to cells from the TIC‐low culture. Studying TICs by using such protocols is cost effective and is considered as a suitable and simple way for studying them. Curr. Protoc. Stem Cell Biol. 24:3.7.1‐3.7.15. © 2013 by John Wiley & Sons, Inc.
First experiences with the GORE® Septal Occluder in children and adults with atrial septal defects
Authors: Nyboe Camilla , Hjortdal Vibeke E. , Nielsen‐Kudsk Jens Erik
Published: February 2013

Objectives

In this study, we report the first experiences with the GORE® Septal Occluder in transcatheter treatment of patients with atrial septal defects (ASD).

Methods

Twenty‐two patients with secundum ASD were selected for GORE® Septal Occluder device closure. Mean age was 25.8 ± 4.6 years (range 4–60), 10 were children below the age of 15. Closure was guided by transeosophageal or intracardiac echocardiography and transthoracic echocardiography was used at follow‐up (median time 3 months). All defects were balloon sized and device size was chosen according to an occluder/defect size ratio ≥2.

Results

The mean ASD size was 11.4 ± 0.5 mm (range 6–15). All GORE® Septal Occluder sizes (15, 20, 25 and 30 mm) were used. Six patients had additional defects. The aortic rim was deficient in twelve patients and four patients had a septal aneurysm. Symptoms were seen in 17 patients and 19 had dilated right ventricles. Implantation was successful in all patients with no complications. Delivery was easy and intuitive by the new delivery system. None of the patients had residual shunts at follow‐up. Mean procedure time was 38 ± 5 min (range 20–120). All patients had resolution or improvement in symptoms. There were no new onset arrhythmias or AV valve regurgitation and right ventricular dimensions were normalized.

Conclusions

The GORE® Septal Occluder is an efficient device for closing ASDs up to 15 mm. It is feasible for defects with different anatomy including a deficient aortic rim, septal aneurysm and multiple fenestrations and due to its compliance and conformability it has a presumed low risk of erosion. © 2013 Wiley Periodicals, Inc.
Aorto‐right atrial fistula secondary to rupture of an occluded old saphenous venous graft to right coronary artery
Authors: Balestrini Carlos Sebastian , Saaibi José Federico , Ortiz Santiago Navas
Published: February 2013

We report a case of an acquired aorta–right atrial fistula, secondary to a ruptured proximal anastomosis of an old saphenous vein graft 12 years after a coronary artery bypass surgery, in a 57 year old patient with multiple cardiovascular risk factors. On admission, he presented with congestive heart failure and on examination a continuous murmur was detected on the right parasternal border. Catheterization showed a fistula from the proximal anastomosis of an occluded right coronary artery saphenous vein graft draining to the right atrium with a large left to right shunt. The fistula was successfully occluded by a percutaneous approach with a Life Tech duct occluder with complete resolution of heart failure. The patient was discharged one week afterwards. After a two‐year follow‐up, the fistula remained occluded. © 2013 Wiley Periodicals, Inc.
ChemInform Abstract: The Fluoride Route to Lindqvist Clusters: Synthesis and Crystal Structure of Layered Hexatantalate Na8Ta6O19·26H2O.
Authors: Britvin Sergey N. , Siidra Oleg I. , Lotnyk Andriy , Kienle Lorenz , Krivovichev Sergey V. , Depmeier Wulf
Published: February 2013

The title compound is synthesized by reacting H2TaF7 with 7M aq.
ChemInform Abstract: Synthesis, Structure, and Spectroscopic Characterization of Three Uranyl Phosphates with Unique Structural Units.
Authors: Wylie Ernest M. , Dawes Colleen M. , Burns Peter C.
Published: February 2013

The crystal structures of (III), (V), and (VII) are determined by single crystal XRD.
ChemInform Abstract: Remarkable Activation of an Alkyne [2 + 2 + 2]‐Cycloaddition Catalyst, 2‐Iminomethylpyridine (dipimp)/CoCl2·6H2O/Zn, by a Phthalate Additive.
Authors: Sugiyama Yu‐ki , Kariwa Takuma , Sakurada Tetsuya , Okamoto Sentaro
Published: February 2013

The procedure provides highly substituted benzene derivatives.
ChemInform Abstract: Regioselective Synthesis of Substituted Naphthalenes and Phenanthrenes by FeCl3‐Promoted Annulation of Aryl and Naphthyl Acetaldehydes with Alkynes.
Authors: Bu Xiuli , Hong Longcheng , Liu Ruiting , Hong Jianquan , Zhang Zhengxing , Zhou Xigeng
Published: February 2013

The present new procedure for the regioselective synthesis of substituted naphthalenes and phenanthrenes is only applicable to internal alkynes.
ChemInform Abstract: Visible‐Light‐Driven Oxidation of 1,3‐Dicarbonyl Compounds via Catalytic Disproportionation of TEMPO by Photoredox Catalysis.
Authors: Koike Takashi , Yasu Yusuke , Akita Munetaka
Published: February 2013

Visible light irradiation of a mixture of 1,3‐dicarbonyls and TEMPO in the presence of a photoredox catalyst affords two types of oxidized products.
ChemInform Abstract: Iron‐Catalyzed Alkyl—Alkyl Suzuki—Miyaura Coupling.
Authors: Hatakeyama Takuji , Hashimoto Toru , Kathriarachchi Kalum K. A. D. S. , Zenmyo Takeshi , Seike Hirofumi , Nakamura Masaharu
Published: February 2013

Magnesium tetraalkylborates prepared from olefins, BH3·Me2S, and iPrMgCl under optimized conditions are coupled with various primary and secondary alkyl bromides to give the corresponding long‐chain alkanes including fatty acid derivatives.
ChemInform Abstract: Direct Amidation of Carboxylic Acids Catalyzed by ortho‐Iodo Arylboronic Acids: Catalyst Optimization, Scope, and Preliminary Mechanistic Study Supporting a Peculiar Halogen Acceleration Effect.
Authors: Gernigon Nicolas , Al‐Zoubi Read M. , Hall Dennis G.
Published: February 2013

The ortho‐iodo arylboronic acid shown in the scheme efficiently promotes the direct amidation of carboxylic acids, which allows convenient formation of a wide range of carboxylic amides.
ChemInform Abstract: Enantioselective Copper‐Catalyzed 1,4‐Addition of Dialkylzincs to Enones Using a Novel N,N,P‐Cu(II) Complex.
Authors: Ebisu Yasuhiro , Kawamura Kenjiro , Hayashi Masahiko
Published: February 2013

The applied chiral ligand is prepared in a five‐step synthesis.
ChemInform Abstract: Rhodium‐Catalyzed [2 + 2] Cycloaddition of Ynamides with Nitroalkenes.
Authors: Smith Donna L. , Chidipudi Suresh Reddy , Goundry William R. , Lam Hon Wai
Published: February 2013

Ynamides bearing an aliphatic substituent generate only an inseparable mixture of diastereomers.
ChemInform Abstract: Direct Transformation of Secondary Amides into Secondary Amines: Triflic Anhydride Activated Reductive Alkylation.
Authors: Xiao Kai‐Jiong , Wang Ai‐E , Huang Pei‐Qiang
Published: February 2013

A one‐pot method for the direct transformation of secondary amides to secondary amines with different substituent patterns is developed.
ChemInform Abstract: Enantioselective Synthesis of Tertiary α‐Hydroxyketones from Unfunctionalized Ketones: Palladium‐Catalyzed Asymmetric Allylic Alkylation of Enolates.
Authors: Trost Barry M. , Koller Raffael , Schaeffner Benjamin
Published: February 2013

Highly functionalized tertiary α‐hydroxyketones are obtained in high yield with excellent enantioselectivity.
ChemInform Abstract: Synthesis of Substituted Phenanthrene by Iron(III)‐Catalyzed Intramolecular Alkyne—Carbonyl Metathesis.
Authors: Bera Krishnendu , Sarkar Soumen , Jalal Swapnadeep , Jana Umasish
Published: February 2013

A new and efficient method to prepare various substituted phenanthrenes is described.
ChemInform Abstract: Organocatalytic Asymmetric Synthesis of 3‐Chlorooxindoles Bearing Adjacent Quaternary—Tertiary Centers.
Authors: Noole Artur , Jaerving Ivar , Werner Franz , Lopp Margus , Milkov Andrei , Kanger Toenis
Published: February 2013

Aliphatic nitroolefins fail to react [cf.(VIa)].
ChemInform Abstract: Lewis Acid‐Catalyzed Friedel—Crafts Alkylations of 3‐Hydroxy‐2‐oxindole: An Efficient Approach to the Core Structure of Azonazine.
Authors: Ghosh Santanu , Kinthada Lakshmana K. , Bhunia Subhajit , Bisai Alakesh
Published: February 2013

A Lewis acid‐catalyzed Friedel—Crafts reaction of electron‐rich aromatics with oxindoles (I) is developed.
ChemInform Abstract: Synthesis of Indolylquinolines, Indolylacridines, and Indolylcyclopenta[b]quinolines from the Baylis—Hillman Adducts: An in situ [1,3]‐Sigmatropic Rearrangement of an Indole Nucleus to Access Indolylacridines and Indolylcyclopenta[b]quinolines.
Authors: Ramesh Chintakunta , Lei Po‐Min , Janreddy Donala , Kavala Veerababurao , Kuo Chun‐Wei , Yao Ching‐Fa
Published: February 2013

The coupling of cyclic Baylis—Hillman adducts like (I), (V), and (X) with indoles is found to result in formation of α‐ or γ‐heteroarylated products depending on the nature of educts.
ChemInform Abstract: Highly Regioselective and Practical Synthesis of 1‐Acyl‐5‐hydroxypyrazolines and 1‐Acyl Pyrazoles from 1,2‐Allenic Ketones and Hydrazides.
Authors: Guo Shenghai , Wang Jiliang , Guo Dongqiang , Zhang Xinying , Fan Xuesen
Published: February 2013

Condensation of allenic ketones (I) with hydrazides results in the formation of hydroxypyrazolines which can be easily converted into the corresponding pyrazoles by dehydration with BF3·Et2O.
ChemInform Abstract: Nitroimidazoles. Part 8. Synthesis and anti‐HIV Activity of New 4‐Nitroimidazole Derivatives Using the Suzuki Cross‐Coupling Reaction.
Authors: Al‐Soud Yaseen A. , Al‐Masoudi Najim A. , Al‐Suod Hossam H. , Pannecouque Christophe
Published: February 2013

Among the newly synthesized compounds, only derivative (Va) inhibits HIV‐1 and HIV‐2 replication.
ChemInform Abstract: Novel Synthesis and Antimicrobial Activity of 3‐Substituted 5‐Bromo‐7‐methyl‐1,2,4‐triazolo‐[3,4‐b]‐benzothiazoles.
Authors: Bhagat T. M. , Deshmukh S. K. , Kuberkar S. V.
Published: February 2013

All new compounds (VI), (VIII), (X) and (XIII) are tested for their antimicrobial activities.
ChemInform Abstract: Efficient and Rapid Synthesis of Highly Functionalized Novel Symmetric 1,4‐Dihydropyridines Using Glacial Acetic Acid as Solvent.
Authors: Thakrar Shailesh , Bavishi Abhay , Bhavsar Dhairya , Parekh Shrey , Vala Hardev , Radadiya Ashish , Parmar Manisha , Savant Mahesh , Shah Anamik
Published: February 2013

Novel 1,4‐dihydropyridines (III) (14 examples) bearing a pyrazole moiety in 4‐position are prepared by a variation of the classical Hantzsch synthesis.
ChemInform Abstract: Iridium‐Catalyzed Oxidant‐Free Dehydrogenative C—H Bond Functionalization: Selective Preparation of N‐Arylpiperidines Through Tandem Hydrogen Transfers.
Authors: Yuan Kedong , Jiang Fan , Sahli Zeyneb , Achard Mathieu , Roisnel Thierry , Bruneau Christian
Published: February 2013

Starting from easily accessible anilines, diols, and aldehydes, the piperidines are prepared by an atom‐economical method which is also compatible with the use of diethyl carbonate as an ecofriendly solvent.
ChemInform Abstract: A Simple Efficient Sequential One‐Pot Intermolecular Aza‐Michael Addition and Intramolecular Buchwald—Hartwig α‐Arylation of Amines: Synthesis of Functionalized Tetrahydroisoquinolines.
Authors: Reddy Alavala Gopi Krishna , Satyanarayana Gedu
Published: February 2013

Tetrahydroisoquinolines (IV) are efficiently synthesized from amines (I) via intermediate β‐aminoesters (III) which are not isolated but directly subjected to Pd‐catalyzed α‐arylation.
ChemInform Abstract: Catalysis by Lithium Perchlorate Enables Double‐Conjugate Addition of Electron‐Deficient Maleimides to 2‐Aminopyridines and 2‐Aminothiazoles.
Authors: Matviiuk Tetiana , Gorichko Marian , Kysil Andriy , Shishkina Svitlana , Shishkin Oleg , Voitenko Zoia
Published: February 2013

Lithium perchlorate is found to catalyze the conjugate addition of maleimides (II) to 2‐aminopyridines or 2‐aminothiazoles.
ChemInform Abstract: Facile Synthesis of 5‐Amino‐ and 7‐Amino‐6‐azaoxindole Derivatives.
Authors: Tzvetkov Nikolay T. , Mueller Christa E.
Published: February 2013

The synthesis of the title compounds, substructures of natural products and medicinal agents, starts with commercially available 2‐amino‐4‐chloropyridine (I).
ChemInform Abstract: Cyclobutene Ring‐Opening of Bicyclo[4.2.0]octa‐1,6‐dienes: Access to CF3‐Substituted 5,6,7,8‐Tetrahydro‐1,7‐naphthyridines.
Authors: Mailyan Artur K. , Peregudov Alexander S. , Dixneuf Pierre H. , Bruneau Christian , Osipov Sergey N.
Published: February 2013

Regioselective ring opening of bicyclo[4.2.0]octadienes followed by intramolecular cyclization of resulting diketones of type (III)/(VI) allows an efficient access to biologically important tetrahydro‐1,7‐naphthyridines.
ChemInform Abstract: Ecofriendly Synthesis of Tetrahydropyrimidine Derivatives in Aqueous Medium under Ultrasonic Irradiation.
Authors: Rao Valasani Koteswara , Babu Boppudi Hari , Babu Kilaru Raveendra , Srinivasulu Doddaga , Raju Chamarthi Naga
Published: February 2013

A simple, efficient, and ecofriendly procedure for the synthesis of tetrahydropyrimidines (III) is given.
ChemInform Abstract: Solid‐State Reactions During High‐Energy Milling of Mixed Powders
Authors: Trapp Johannes , Kieback Bernd
Published: February 2013

Review: emphasis on the formation of borides and carbides; 36 refs.
ChemInform Abstract: Diazo Hydroxides, Diazo Ethers and Related Species
Authors: Bravo‐Diaz Carlos D.
Published: February 2013

Review: 93 refs.
ChemInform Abstract: Bowl‐to‐Bowl Inversion of Sumanene Derivatives
Authors: Amaya Toru , Hirao Toshikazu
Published: February 2013

Review: 31 refs.
ChemInform Abstract: Organic Solid‐State Fluorescence: Strategies for Generating Switchable and Tunable Fluorescent Materials
Authors: Anthony Savarimuthu Philip
Published: February 2013

Review: 210 refs.
ChemInform Abstract: 1,1′‐Bis(diphenylphosphino)ferrocene in Functional Molecular Materials
Authors: Young David J. , Chien Sheau Wei , Hor T. S. Andy
Published: February 2013

Review: 59 refs.
ChemInform Abstract: Introduction to Electron Paramagnetic Resonance
Authors: Brustolon Marina , Van Doorslaer Sabine
Published: February 2013

Review: 61 refs.
Long telomeres in peripheral blood leukocytes are associated with an increased risk of soft tissue sarcoma
Authors: Xie Hui , Wu Xifeng , Wang Shui , Chang David , Pollock Raphael E. , Lev Dina , Gu Jian
Published: February 2013

BACKGROUND:

Human telomeres consisting of long, tandem repeats of the nucleotide sequence TTAGGG at the chromosome ends are essential for maintaining chromosomal stability. Previous epidemiologic studies have indicated that shorter telomere length in peripheral blood leukocytes (PBLs) is associated with the development of many cancers. However, the relation between PBL telomere length and the risk of soft tissue sarcoma (STS) has not been investigated.

METHODS:

The relative telomere length (RTL) was determined in PBLs using real‐time polymerase chain reaction in this case‐control study. The study participants included 137 patients with histologically confirmed STS (cases) who had received no prior chemotherapy or radiotherapy and 137 healthy controls who were frequency‐matched to cases on age, sex, and ethnicity.

RESULTS:

Patients in the case group had significantly longer RTL than controls (1.46 ± 0.42 for cases vs 1.15 ± 0.39 for controls; P < .001). By using median RTL in the controls as a cutoff level, individuals who had long telomere length were associated with a significantly increased risk of STS compared with those who had short telomere length (adjusted odds ratio, 4.71; 95% confidence interval, 2.63‐8.44). When participants were categorized further into 3 or 4 groups according to the tertile or quartile RTL values of healthy controls, a significant dose‐response relation was observed between longer RTL and increased risks of STS.

CONCLUSIONS:

The current results provided the first epidemiologic evidence that longer telomere length in PBLs is associated significantly with an increased risk of STS, potentially suggesting an important role for telomere maintenance in STS development. Cancer 2013. © 2013 American Cancer Society.
Harmony at LAST
Authors: Wilbur David C. , Darragh Teresa M.
Published: February 2013

The joint College of American Pathologists/American Society for Colposcopy and Cervical Pathology LAST Project provides evidence‐based consensus recommendations for a unified terminology for histopathologic classification of all human papillomavirus–associated squamous lesions of the lower anogenital tract. It also includes specific recommendations for biomarker use to increase reliability and reproducibility of histopathologic diagnoses.
Inefficient antimicrobial functions of innate phagocytes render infant mice more susceptible to bacterial infection
Authors: Zhang Qi , Coveney Andrew P. , Yu Shenglin , Liu Jing Hua , Li Yiping , Blankson Siobhan , Redmond H. Paul , Wang Jiang Huai , Wang Jian
Published: February 2013

Neonates and infants, due to the immaturity in their adaptive immunity, are thought to depend largely on the innate immune system for protection against bacterial infection. However, the innate immunity‐mediated antimicrobial response in neonates and infants is incompletely characterized. Here, we report that infant mice were more susceptible to microbial sepsis than adult mice, with significantly reduced bacterial clearance from the circulation and visceral organs. Infant PMNs exhibited less constitutive expression of the chemokine receptor CXCR2, and bacterial infection caused further reduction of PMN CXCR2 in infant mice compared with adult mice. This correlates with diminished in vitro chemotaxis of infant PMNs toward the chemoattractant CXCL2 and impaired in vivo recruitment of infant PMNs into the infectious site. Furthermore, consistent with the reduced antimicrobial response in vivo, infant macrophages displayed an impaired bactericidal activity with a defect in phagosome maturation after ingestion of either gram‐positive or gram‐negative bacteria. Thus, infant mice exhibit an increased vulnerability to microbial infection with delayed bacterial clearance, which is associated with the inefficiency in their innate phagocyte‐associated antimicrobial functions characterized by defects in PMN recruitment and macrophage phagosome maturation during microbial sepsis.
Water‐Soluble Phosphanes Derived from 1,3,5‐Triaza‐7‐phosphaadamantane and Their Reactivity towards Gold(I) Complexes
Authors: García‐Moreno Elena , Cerrada Elena , Bolsa M. José , Luquin Asunción , Laguna Mariano
Published: February 2013

New water‐soluble phosphanes derived from 1,3,5‐triaza‐7‐phosphaadamantane, namely, [PTA–R]Br (R = –CH2C≡CH, –CH2CONH2, –CH2COOH), are described. Coordination of these phosphanes and their previously reported counterparts (R = –CH2CN, –CH2Ph and –CH2COOMe) to gold(I) salts gives water‐soluble derivatives with chlorido, bromido or pentafluorophenyl coligands. The luminescence properties of all new compounds have been studied in the solid state and compared with the respective free PTA ligands. [PTA–CH2Ph]Br, [PTA–CH2COOMe]Br and [AuBr(PTA–CH2Ph)]Br have also been characterised by X‐ray diffraction analysis. Some of the new gold(I) compounds exhibit strong antiproliferative effects in the human ovarian carcinoma cell line A2780 and its cisplatin‐resistant variant (A2780cisR). A balanced relationship between lipophilicity and hydrophilicity is found in these derivatives, with distribution coefficients (log D7.4) that range from 0.14 to –0.40.
Synthesis of N‐Alkenylpurines by Rearrangements of the Corresponding N‐Allyl Isomers: Scopes and Limitations
Authors: Kania Jindrich , Gundersen Lise‐Lotte
Published: February 2013

N‐9‐ and N‐7‐alkenylpurines have been synthesized by rearrangement of the corresponding N‐allyl derivatives, often in good yields and with high stereoselectivity. Base promoted and transition metal mediated rearrangements have been studied. Simple allylpurines were easily rearranged with catalytic amounts of RuClH(CO)(PPh3)3. The efficiency of base promoted rearrangement was highly dependent on the detailed structure of the starting material, but this reaction often occurred with surprisingly high Z‐selectivity.
Re‐evaluating genetic models for porphyry Mo mineralization at Questa, New Mexico: Implications for ore deposition following silicic ignimbrite eruption
Authors: Rosera Joshua M. , Coleman Drew S. , Stein Holly J.
Published: February 2013

The Questa porphyry Mo deposit in New Mexico provides a unique opportunity to study the relationship between pluton assembly and mineralization in a long‐lived volcanic field. Magmatism along the caldera margin initiated at ~ 25.20 Ma and continued for ~ 770 ka. During this time, the emplacement of mineralizing intrusions progressed westward and culminated in the assembly of the Questa Mo deposit between 24.76 Ma and 24.50 Ma. Molybdenite Re/Os geochronology shows that mineralization occurred in multiple pulses without thermal resetting of the chronometer. Because most of the molybdenite samples used in this study are from previous fluid inclusion studies, we treat Re/Os molybdenite as a new thermochronometer. Molybdenite Re/Os ages are integrated with zircon U/Pb ages to evaluate the cooling histories within the Mo deposit. This study suggests that individual cycles of magma emplacement and mineralization cooled rapidly. In contrast to prior genetic models for the Questa Mo deposit, these data show that the mineralizing intrusions were generated via rapid melt generation, separation, and intrusion into the shallow crust without involvement in a long‐lived magma chamber. It is proposed that the anomalously high magma flux event associated with ignimbrite eruption transferred materials (Mo, volatiles) from the upper mantle necessary for immediately subsequent mineralization. Partial melting and scavenging within a deep‐crustal hybridized zone generated Mo‐rich magma that ascended to form the Questa deposit. Moreover, this hypothesis predicts an important connection between caldera‐forming systems and porphyry‐style mineralization that could be incorporated into future exploration models.
Microglia and macrophages differentially modulate cell death after brain injury caused by oxygen‐glucose deprivation in organotypic brain slices
Authors: Girard Sylvie , Brough David , Lopez‐Castejon Gloria , Giles James , Rothwell Nancy J. , Allan Stuart M.
Published: February 2013

Macrophage can adopt several phenotypes, process call polarization, which is crucial for shaping inflammatory responses to injury. It is not known if microglia, a resident brain macrophage population, polarizes in a similar way, and whether specific microglial phenotypes modulate cell death in response to brain injury. In this study, we show that both BV2‐microglia and mouse bone marrow derived macrophages (BMDMs) were able to adopt different phenotypes after LPS (M1) or IL‐4 (M2) treatment in vitro, but regulated cell death differently when added to mouse organotypic hippocampal brain slices. BMDMs induced cell death when added to control slices and exacerbated damage when combined with oxygen–glucose deprivation (OGD), independently of their phenotype. In contrast, vehicle‐ and M2‐BV2‐microglia were protective against OGD‐induced death. Direct treatment of brain slices with IL‐4 (without cell addition) was protective against OGD and induced an M2 phenotype in the slice. In vivo, intracerebral injection of LPS or IL‐4 in mice induced microglial phenotypes similar to the phenotypes observed in brain slices and in cultured cells. After injury induced by middle cerebral artery occlusion, microglial cells did not adopt classical M1/M2 phenotypes, suggesting that another subtype of regulatory phenotype was induced. This study highlights functional differences between macrophages and microglia, in response to brain injury with fundamentally different outcomes, even if both populations were able to adopt M1 or M2 phenotypes. These data suggest that macrophages infiltrating the brain from the periphery after an injury may be cytotoxic, independently of their phenotype, while microglia may be protective.
Mapping HF waves in the reconnection diffusion region
Authors: Viberg H. , Khotyaintsev Yu.V. , Vaivads A. , André M. , Pickett J.S.
Published: February 2013

We study in detail high‐frequency (HF) plasma waves between the electron cyclotron and plasma frequencies within a reconnection diffusion region (DR) encountered by Cluster in the magnetotail using continuous electric field waveforms. We identify three wave types, all observed within the separatrix regions: Langmuir waves (LW), electrostatic solitary waves (ESWs), and electron cyclotron waves (ECWs). This is the first time the ECWs have been observed inside this region. Direct comparison between waveforms and electron distributions are made at the timescale of one energy sweep of the electron detector (125 ms). Based on the wave and electron distribution characteristics, we find that the separatrix region has a stratified spatial structure. The outer part of the region is dominated by LW emissions related to suprathermal electron beams propagating away from the X‐line. Furthest in, nearest to the current sheet, we observe ESWs associated with counterstreaming electron populations. Studying HF waveforms allows for a precise mapping of kinetic boundaries in the reconnection region and helps to improve our understanding of the electron dynamics in the DR.
An adaptive dynamic combined energy minimization model for few‐view computed tomography reconstruction
Authors: Feng Jun , Zhang Jian‐Zhou
Published: February 2013

Recently, the potential harm of electromagnetic radiation used in computed tomography (CT) scanning has been paid much attention to. This makes the few‐view CT reconstruction become an important issue in medical imaging. In this article, an adaptive dynamic combined energy minimization model is proposed for few‐view CT reconstruction based on the compress sensing theory. The L2 energy of the image gradient and the total variation (TV) energy are combined, and the working regions of them are separated adaptively with a dynamic threshold. With the proposed model, the TV model's disadvantageous tendency of uniformly penalize the image gradient irrespective of the underlying image structures is overcome. Numerical experiments of the proposed model are performed with various insufficient data problems in fan‐beam CT and suggest that both the reconstruction speed and quality of the results are generally improved. © 2013 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 23, 44–52, 2013.
Linearity condition for orbital energies in density functional theory (III): Benchmark of total energies
Authors: Imamura Yutaka , Kobayashi Rie , Nakai Hiromi
Published: February 2013

This study presents a numerical assessment of total energy related physical quantities estimated using the orbital‐specific (OS) global and range‐separated hybrid functionals, designed to satisfy the linearity condition for orbital energies (LCOE). The numerical assessment demonstrates that accurate evaluation of the reaction energies, reaction barrier, and dissociation curve can be achieved via the OS hybrid functional, for systems in which self‐interaction is expected to be dominant. Therefore, the LCOE offers an accurate description of orbital energies as well as total energies for self‐interaction dominant systems. © 2013 Wiley Periodicals, Inc.
Enantioselective liquid–liquid extraction of (D, L)‐valine using metal–BINAP complex as chiral extractant
Authors: Tang Kewen , Fu Tao , Zhang Panliang
Published: February 2013

Background

Enantioselective liquid–liquid extraction is a very attractive technology for the production of enantiomerically pure compounds. The objective of this research is to investigate enantioselective liquid–liquid extraction of valine (Val) enantiomers with metal–BINAP complexes as enantioselective extractants.

Results

Results show that BINAP complex with copper(I) as central ion allows the separation of Val enantiomers with the highest operational selectivity. Efficiency of the extraction depends, often strongly, on a number of process variables, including types of organic solvents, pH of the aqueous phase, concentration of host and substrate, and temperature. Extraction performance of the system can be accurately predicted by the model. By modeling and experiment, an optimal extraction condition was obtained at a pH of 8 and the host concentration of 2.0 × 10‐3 mol L‐1 with the highest enantioselective (α) of 3.65 and performance factor (pf) of 0.086.

Conclusions

The presented data indicate that Val enantiomers can be efficiently separated by enantioselective liquid–liquid extraction. The model provides a powerful tool for calculating distribution ratio, enantioselectivity, enantiomeric excess and performance factor. It can be used for optimization of the reactive extraction systems. This paper can provide some valuable fundamental data for the production of enantiomerically pure amino acid enantiomers. © 2013 Society of Chemical Industry
THE EFFECTS OF RESPONSE‐COST PUNISHMENT ON INSTRUCTIONAL CONTROL DURING A CHOICE TASK
Authors: Fox Adam E. , Pietras Cynthia J.
Published: February 2013

The present study investigated the effects of punishing responses inconsistent with rules on instructional control during a choice task. In a procedure modeled after Hackenberg and Joker (1994), 7 adults were presented with repeated choices between progressive‐ and fixed‐time schedules of reinforcement and were given instructions (rules) for how to respond to maximize earnings. Across sessions, the progressive‐time schedule step size was manipulated so that the instructions became increasingly inaccurate, and deviating from the instructions produced greater earnings. The experiment consisted of two phases, Penalty and No Penalty. During the Penalty phase, deviating from the instructions produced a money‐loss penalty (response‐cost punishment). Two participants showed persistent instructional control and therefore completed only one phase (Penalty or No Penalty), and 1 participant showed little instructional control during the Penalty phase until the punishment magnitude was increased. In all 4 participants who experienced both Penalty and No Penalty phases, punishment increased the consistency of choices with the instructions, and in 2 of these participants punishment increased the progressive‐schedule step size at which choices began to systematically deviate from the instructions. These results show that monetary penalties for breaking with rules may enhance instructional control, but that deviations from rules still occur under punishment when such deviations produce greater reinforcement than rule following.
Ultrastructure of neurosecretory granule exocytosis by crayfish sinus gland induced with ionic manipulations
Authors: David ANDREW R. , Shivers Richard R.
Published: February 2013

Neurosecretory granule exocytosis from axon terminals in the crayfish (Orconectes virilis) sinus gland can be effected by alterations in intracellular ionic concentrations through modification of the bathing medium or by electrical stimulation. This may result in increased numbers of exocytotic profiles involving one granule (single exocytosis) or several granules (compound exocytosis), which we interpret as evidence of stimulated neurosecretion. Our results suggest that increased free intracellular Ca++ together with a decrease in intracellular K+ are prerequisite for and sufficient to elicit increased exocytosis from sinus gland terminals. Similar release, stimulated by horseradish peroxidase, indicates that local surface permeability changes are involved. A minor response to high‐K+‐Ringer, and secretion via compound exocytosis, are uncharacteristic of cells with a neural ancestry.
Incorporating endorectal MR elastography into multi‐parametric MRI for prostate cancer imaging: Initial feasibility in volunteers
Authors: Arani Arvin , Da Rosa Michael , Ramsay Elizabeth , Plewes Don B. , Haider Masoom A. , Chopra Rajiv
Published: February 2013

Purpose

To investigate the tolerability and technical feasibility of performing endorectal MR elastography (eMRE) in human volunteers within the representative age group commonly affected by prostate cancer.

Materials and Methods

Endorectal MRE was conducted on seven volunteers in a 1.5 Tesla (T) MR imager using a rigid endorectal coil. Another five volunteers were imaged on a 3T MR imager using an inflatable balloon type endorectal coil. Tolerability was accessed for vibration amplitudes of ±1–50 μm and for frequencies of 100–300 Hz.

Results

All 12 volunteers tolerated the displacements necessary to successfully perform eMRE. Shear waves with frequencies up to 300 Hz could propagate across the entire prostate using both coil designs.

Conclusion

The results of this study motivate further investigation of eMRE in prostate cancer patients to help determine if there is an added value of integrating eMRE into existing multi‐parametric prostate MRI exams. J. Magn. Reson. Imaging 2013;38:1251–1260. © 2013 Wiley Periodicals, Inc.
Serologic evidence of avian influenza virus infections among Nigerian agricultural workers
Authors: Okoye John , Eze Didacus , Krueger Whitney S. , Heil Gary L. , Friary John A. , Gray Gregory C.
Published: February 2013

Nigeria has had multiple incursions of highly pathogenic avian influenza A (HPAI) H5N1 virus into its poultry population since 2006. This study aimed to determine if Nigerians exposed to poultry had evidence of avian influenza virus transmission to man. Between 2008 and 2010, 316 adult farmers and open market workers and 54 age‐group matched, non‐animal exposed controls were enrolled in a prospective, population‐based study of zoonotic influenza transmission in four towns in southeastern Nigeria. Questionnaire data and sera obtained at the time of enrollment were examined for evidence of previous infection with 10 avian influenza virus strains. Serologic studies on sera collected at the time of enrollment showed modest evidence of previous infection with three avian‐origin influenza viruses (H5N1, H5N2, and H11N1) and one avian‐like H9N2 influenza virus, with eight (2.4%) of animal‐exposed subjects and two (3.7%) unexposed subjects having elevated microneutralization assay antibody titer levels (ranging from 1:10 to 1:80). Statistical analyses did not identify specific risk factors associated with the elevated antibody titers observed for these zoonotic influenza viruses. These data suggested only occasional virus transmission to humans in areas thought to have been enzootic for avian influenza virus. Prospective data from this cohort will help the authors to better understand the occurrence of zoonotic infections due to avian influenza viruses in Nigeria. J. Med. Virol. 85:670–676, 2013. © 2013 Wiley Periodicals, Inc.
SIRT1 regulates the neurogenic potential of neural precursors in the adult subventricular zone and hippocampus
Authors: Saharan Sumiti , Jhaveri Dhanisha J. , Bartlett Perry F.
Published: February 2013

Within the two neurogenic niches of the adult mammalian brain, i.e., the subventricular zone lining the lateral ventricle and the subgranular zone of the hippocampus, there exist distinct populations of proliferating neural precursor cells that differentiate to generate new neurons. Numerous studies have suggested that epigenetic regulation by histone‐modifying proteins is important in guiding precursor differentiation during development; however, the role of these proteins in regulating neural precursor activity in the adult neurogenic niches remains poorly understood. Here we examine the role of an NAD+‐dependent histone deacetylase, SIRT1, in modulating the neurogenic potential of neural precursors in the neurogenic niches of the adult mouse brain. We show that SIRT1 is expressed by proliferating adult subventricular zone and hippocampal neural precursors, although its transcript and protein levels are dramatically reduced during neural precursor differentiation. Utilizing a lentiviral‐mediated delivery strategy, we demonstrate that abrogation of SIRT1 signaling by RNAi does not affect neural precursor numbers or their proliferation. However, SIRT1 knock down results in a significant increase in neuronal production in both the subventricular zone and the hippocampus. In contrast, enhancing SIRT1 signaling either through lentiviral‐mediated SIRT1 overexpression or through use of the SIRT1 chemical activator Resveratrol prevents adult neural precursors from differentiating into neurons. Importantly, knock down of SIRT1 in hippocampal precursors in vivo, either through RNAi or through genetic ablation, promotes their neurogenic potential. These findings highlight SIRT1 signaling as a negative regulator of neuronal differentiation of adult subventricular zone and hippocampal neural precursors. © 2013 Wiley Periodicals, Inc.