bluuebunny/crossref_metadata_2025 huggingface dataset:
Observations on cortical‐cell size and arrangement in some animal fibres
Authors: APPLEYARD H. M.
Published: November 2011

SYNOPSIS

The relation between the size and number of cortical cells and fibre thickness is discussed with reference to various animal fibres, including several types of wool, cashmere, alpaca, and camel hair. It was found that it was possible to distinguish camel hair in a mixture from the other fibres examined on the basis of cortical‐cell size but this was the limit of positive identification by this method. The arrangement and shape of cortical cells in fibres of different cross‐sectional shape was also compared.
Preparation of rodent kidney for light microscopy by freeze‐drying and embedding in water‐soluble methacrylate
Authors: MIDDLETON E.
Published: November 2011

SYNOPSIS

Methods for the elimination of five main artifacts common to frozen‐dried specimens embedded in methacrylate are described in detail. Two of these are associated with the drying technique and three to the methacrylate embedding process. One of the “drying” artifacts, contamination of the tissues by pump oil, can be overcome by inserting an oil trap between the vacuum pump and the freeze‐dryer. The other, “zoning” in the specimens, is shown to be due to incomplete drying. Using an Edwards TD2 or TD4 freeze dryer a point in the drying process is reached when the pressure exerted by the water extracted from the specimens equals that exerted by the residual water within the specimens. Drying then ceases and cannot be completed merely by prolonging the procedure. To complete drying, the tissues are transferred to a second clean drying head and the process is repeated.

Good impregnation of tissues is achieved by evacuating them in a chamber before adding the methacrylate, which is then allowed to penetrate the tissues at atmospheric pressure. This calls for a viscous methacrylate such as the glycol compound. The rate of penetration varies greatly for different tissues and methacrylates and a glycol/butyl methacrylate mixture penetrates frozen‐dried kidney very slowly at a rate of about 1 mm in twelve hours. The remaining artifacts are ballooning of the tissues, leaching out of material from them, and bubbling of the methacrylate. The properties of glycol, butyl, and methyl methacrylates, alone and in mixtures, have been studied in association with different catalyst concentrations. A mixture of 85 p.c. distilled glycol and 15 p.c. distilled butyl methacrylate with 0.5 p.c. benzoyl peroxide catalyst added, satisfies the vacuum embedding requirements, obviates ballooning of tissues and leaching out of material from them, does not bubble and produces a block with an acceptable cutting texture. It is necessary to polymerize some of the mixture to within ½ hour of completion for casting the final block.
The future of the electron microscope*
Authors: COSSLETT V. E.
Published: November 2011

SYNOPSIS

The future of electron microscopy lies as much with the conventional as with the newer instruments. The point resolving power of the latter is likely to be pushed to 1 Å, but only after a considerable effort in solving problems of mechanical and electrical stability. Progress in correcting the lens aberrations is even slower. Techniques of specimen preparation and microscope operation are continuously being improved, but will need even greater refinement if proper use is to be made of a 1 Å resolving power, e.g. for identifying bases in a nucleic acid molecule. Extension of the working voltage to 1 MeV and above is increasing the usefulness of the conventional electron microscope, particularly in metallurgy, and plans are now being made for even higher voltages.

Of the newer, unconventional instruments, the scanning electron microscope is already establishing a place for itself, especially in industrial applications where surface conditions on the microscale are important. It is likely to find increasing use in micro‐circuitry, but also in some branches of biological research, even if its resolving power cannot be brought below 100 Å. The combination of X‐ray spectrometry with electron microscopy holds promise of wide application, in the form of a hybrid electron microscope‐microanalyser. Secondary‐emission microscopes are slowly finding a place for themselves, mainly in applied science and technology. Mirror microscopes, for surface investigations, and ion microscopes, for microanalysis, are still in an early stage but have interesting possibilities. The field ion microscope, simplest in principle but sophisticated in technique, is unique in showing the position of individual atoms in a metal tip. It is already finding applications, especially in studies of radiation damage.
The xylem fibres of Salix fragilis, L
Authors: ROBARDS A. W.
Published: November 2011

SYNOPSIS

Gelatinous fibres of Salix fragilis L. are characterized by an inner layer of cellulose which is relatively unlignified when compared with normal wood fibres. The gelatinous layers of mature gelatinous fibres sometimes show a reaction with benzidine or with ruthenium red. Fibres may sometimes have a terminal lamella which borders the lumen. It is suggested that the irregular distribution of organelles within differentiating fusiform cells is responsible for the spasmodic histochemical reactions and presence of a terminal lamella.

The Coppick and Fowler method may be used for the localization of lignin in ultra‐thin sections.

Although starch grains have often been seen within fibres, their presence has not been clearly related to the presence of gelatinous fibres alone.

From light, polarizing and electron microscopical evidence, the walls of normal wood fibres have been found to be composed of S1 + S2 + S3 layers or of S1 + S2 layers only. The gelatinous fibres invariably have a gelatinous layer which may replace either the S3 or both the S3 + S2 layers.

Microfibrillar disorientations of the gelatinous layer as seen in carbon replicas appear to be caused by the presence of simple pits or incipient slip planes. It appears that the pits through the gelatinous layer may become distended during processing for light microscopy.

The convoluted appearance of the gelatinous layer in some sections is now considered to be an artifact brought about by processing and sectioning of fibres.

No evidence has been found that the gelatinous layer is formed other than by the gradual deposition of wall material, whether or not there may be periods of faster or slower wall synthesis.
Fine structure of Sfapheardella tceniformis (Foraminifera: Protozoa)
Authors: HEDLEY R. H. , PARRY D. M. , WAKEFIELD J. ST. J.
Published: November 2011

SYNOPSIS

A survey of ultrastructure in the relatively large Shepheardella tceniformis (Foraminifera) reveals several features not observed previously in this group of protozoans. Microtubules, 210–250 A in diameter, occurring in the pseudopodia and also in the cytoplasm, where they form a 1–2 μ peripheral layer, are illustrated and their possible function discussed. The huge interphasic nucleus has an envelope, roughly comparable but more complex than that found in Amoeba, which reverts to a conventional nuclear membrane during division. In the cytoplasm there are numerous 0.5 μ microbodies, of unknown function, superficially resembling vertebrate hepatic uricosomes, and which, so far as is known, are unique in protozoan ultra‐structure.
Changes in the fine structure of the mouse pancreatic acinar cell after fixation by chromium trioxide
Authors: MCCRAE J. M.
Published: November 2011

SYNOPSIS

The exocrine pancreatic cell of the mouse was the test object for the investigation. Tissue fixed with a 0.5 p.c. aqueous solution of chromium trioxide was embedded in Araldite and sections were examined with the electron microscope.

Chromium trioxide does not convert the cytoplasm into a coagulum. What appears to be a coagulum in optical microscopy is in fact a three‐dimensional network of ergastoplasm (endoplasmic reticulum), the cisterna of which retain their identity (though the ribosomes are not preserved).

The mitochondria are not destroyed, but no internal structure is seen. No vestige of the Golgi element remains.

The inner nuclear membrane is preserved, the outer only here and there. Nothing that could be interpreted as a thread‐like structure is seen in the nucleus. The nucleolus appears homogeneous.
Phylogenetic evidence for loss of sound production and a shift in sexual recognition signals in Hamadryas butterflies (Nymphalidae: Biblidinae)
Authors: GARZÓN‐ORDUÑA IVONNE J.
Published: November 2011

The neotropical butterfly genus Hamadryas Hübner comprises 20 species that exhibit an intriguing variation in their natural history traits. Although revised in 1983, no phylogenetic hypothesis was presented: the first phylogenetic hypothesis is estimated here based on 93 characters and including species from the three other genera in the tribe Ageroniini. The phylogeny is used to test the monophyly of the genus, establish the sister group of Hamadryas and identify its apomorphies. The tree allows the inference of patterns of character change in sound production and sexual dimorphism. Implied weights show that Hamadryas is monophyletic and corroborate Ectima Doubleday as a sister genus. Previously suggested subgenera for Hamadryas were non‐monophyletic, with the exception of the laodamia clade, supported by the presence of a complete sterigma. Sound production is inferred to be a derived condition in Hamadryas that has been lost in the laodamia clade. This, plus the presence of androconial organs and sexual dimorphism in the laodamia clade, suggests a shift in sexual recognition signalling. Furthermore, the phylogeny indicates that the colour pattern of males in the laodamia clade is novel, supporting a Darwinian origin of sexual dimorphism.
How to develop a simulation programme in urology
Authors: Ahmed Kamran , Amer Tarik , Challacombe Ben , Jaye Peter , Dasgupta Prokar , Khan Mohammad Shamim
Published: November 2011

What's known on the subject? and What does the study add?

Inanimate trainers and simulators have been shown to facilitate the skill acquisition of urologists. However, there are significant challenges to integrating standalone simulation programmes into mainstream urology curricula.

This study provides a framework to overcome these challenges and discusses the advantages of centralised urology simulation centres and their potential to serve as key adjuncts in the certification and validation process of urologists.

Fixed performance‐based outcomes of inanimate trainers and simulators have been praised as useful adjuncts in urology for reducing the learning curve associated with the acquisition of new technical and non‐technical skills without compromising patient safety. Simulators are becoming an integral part of the urology training curriculum and their effectiveness is totally dependent on the structure of the programme implemented. The present paper discusses the fundamental concepts of centralized urology centres and their potential to serve as key adjuncts in the certification and validation process of urologists. In summary, proficiency‐based curricula with well structured endpoints and objective tools for validating proficiency are critical in developing a simulation programme in urology. We concludes that more educational research into the outcomes of integrated urology curricula followed by trainee/trainer opinion surveys will help address some of these criteria.
The biogeography and filtering of woody plant functional diversity in North and South America
Authors: Swenson Nathan G. , Enquist Brian J. , Pither Jason , Kerkhoff Andrew J. , Boyle Brad , Weiser Michael D. , Elser James J. , Fagan William F. , Forero‐Montaña Jimena , Fyllas Nikolaos , Kraft Nathan J. B. , Lake Jeffrey K. , Moles Angela T. , Patiño Sandra , Phillips Oliver L. , Price Charles A. , Reich Peter B. , Quesada Carlos A. , Stegen James C. , Valencia Renato , Wright Ian J. , Wright S. Joseph , Andelman Sandy , Jørgensen Peter M. , Lacher Jr Thomas E. , Monteagudo Abel , Núñez‐Vargas M. Percy , Vasquez‐Martínez Rodolfo , Nolting Kristen M.
Published: November 2011

Aim  In recent years evidence has accumulated that plant species are differentially sorted from regional assemblages into local assemblages along local‐scale environmental gradients on the basis of their function and abiotic filtering. The favourability hypothesis in biogeography proposes that in climatically difficult regions abiotic filtering should produce a regional assemblage that is less functionally diverse than that expected given the species richness and the global pool of traits. Thus it seems likely that differential filtering of plant traits along local‐scale gradients may scale up to explain the distribution, diversity and filtering of plant traits in regional‐scale assemblages across continents. The present work aims to address this prediction.

Location  North and South America.

Methods  We combine a dataset comprising over 5.5 million georeferenced plant occurrence records with several large plant functional trait databases in order to: (1) quantify how several critical traits associated with plant performance and ecology vary across environmental gradients; and (2) provide the first test of whether the woody plants found within 1° and 5° map grid cells are more or less functionally diverse than expected, given their species richness, across broad gradients.

Results  The results show that, for many of the traits studied, the overall distribution of functional traits in tropical regions often exceeds the expectations of random sampling given the species richness. Conversely, temperate regions often had narrower functional trait distributions than their smaller species pools would suggest.

Main conclusion  The results show that the overall distribution of function does increase towards the equator, but the functional diversity within regional‐scale tropical assemblages is higher than that expected given their species richness. These results are consistent with the hypothesis that abiotic filtering constrains the overall distribution of function in temperate assemblages, but tropical assemblages are not as tightly constrained.
Quaternary and pre‐Quaternary historical legacies in the global distribution of a major tropical plant lineage
Authors: Kissling W. Daniel , Baker William J. , Balslev Henrik , Barfod Anders S. , Borchsenius Finn , Dransfield John , Govaerts Rafaël , Svenning Jens‐Christian
Published: November 2011

Aim  The relative importance of current climate and past historical legacies is hotly debated. Here, we assess their role in determining the global distribution and diversity patterns of palms (Arecaceae), a widespread, species‐rich group of keystone ecological importance in tropical ecosystems.

Location  Global.

Methods  We assembled country‐level species lists world‐wide and compiled associated data on potential contemporary environmental drivers (current climate, habitat heterogeneity, area, and insularity), Quaternary glacial–interglacial climate change and major biogeographic regions to evaluate to what extent the global distribution and species richness patterns in palms reflect Quaternary climatic oscillations or regional effects reflecting pre‐Quaternary legacies. We also assessed for the first time if historical legacies differ between continents and islands, providing novel insights into determinants of insular species richness.

Results  Palm species richness was significantly affected by Quaternary climate changes and further differed between biogeographic regions even when both current environmental conditions and Quaternary climate changes were accounted for. In contrast, global limits to the distribution of the palm family were best explained by current temperature while biogeographic regional differences were unimportant and Quaternary climate change caused only a small constraint. Historical legacies were weak on islands, with only a small regional effect and no effect of Quaternary climate changes.

Main conclusions  Strong historical legacies supplement current environment as determinants of palm species richness. These primarily comprise pre‐Quaternary historical effects, reflected in low African species richness (possibly linked to pre‐Quaternary extinctions) and outstandingly high Neotropical and Indomalayan palm species richness (possibly linked to these regions' long‐term climatic suitability for palms). In contrast to species richness, the global distribution of the family range is largely in equilibrium with current climate. The small historical effects on islands are consistent with climatic buffering from their oceanic environment.
Punishing Women, 1880–1905
Authors: Turner Jo
Published: November 2011

Police, prison and court data show that during the late 19th and early 20th Centuries Stafford magistrates overwhelmingly imposed small fines or short prison sentences on the women coming before them. The offending trajectories of the repeat female offenders in Stafford show that for most of them such punishments either had little or no deterrent effect. However those women who were perceived to live beyond the safe haven of a family were more likely not only to be sentenced to custody but also to find their custodial sentences becoming successive which, in turn, exacerbated their offending.
Introduction to a Virtual Special Issue on calcium signalling in plants
Authors: Brownlee Colin , Hetherington Alistair
Published: November 2011

Link to the Virtual Special Issue
Pentecostal dreaming and technologies of governmentality in a Melanesian society
Authors: EVES RICHARD
Published: November 2011

Among the Lelet of central New Ireland (Papua New Guinea), a dramatic increase in Pentecostalist fervor has produced significant changes in dreaming. Traditionally, the Lelet have valued dreaming as a means of access to knowledge and power. Now it is seen as a gift bestowed by the Holy Spirit, giving access to new and different forms of knowledge and power. Pentecostalism lays down many rules of conduct for the avoidance of sin, and dreams now play a role in policing them. Drawing on Michel Foucault's work on governmentality, I find that Lelet dreaming acts as a form of self‐scrutiny, reminding dreamers of the need to rectify their failures to follow Pentecostal precepts. Beyond this, dreams enable people to address the dilemmas that emerge when they embrace frameworks that impose radically different ways of being in the world than their previous religion did.
Mobility, liminality, and embodiment in urban Egypt
Authors: GHANNAM FARHA
Published: November 2011

In this article, I analyze urban mobilities by looking closely at the lives of a brother and sister from a low‐income neighborhood in Cairo, Egypt, and examining their individual mobilities in the context of Victor Turner's work on liminality and Pierre Bourdieu's writing on habitus and bodily hexis. I approach daily mobilities as embodied liminal encounters that are open to multiple possibilities. I show that the liminality of mobility may be the grounds for the reflection and reproduction of social hierarchies but may also create opportunities for questioning and reconfiguring inequalities, particularly in regard to class and gender.
Integrated pest management theory and practice
Authors: Kogan Marcos
Published: November 2011

Integration in pest management may be conceived at three distinct levels: (a) integration of tactics, (b) integration of the effects of multiple pest stresses, and (c) systems integration. The ecological basis of each is found in population, community or ecosystems processes, respectively. Most current IPM programs are attempts to integrate control tactics into management strategies and therefore only require knowledge of species and population ecology. Further advancement of IPM will require higher levels of integration but the experimental basis of and information on community and ecosystems processes are insufficient to permit reaching these levels. Mostly entomological examples in the grain legumes are used to demonstrate achievements of IPM at level a (tactical integration), and the difficulties involved in advancing towards integration of multiple pest stresses and systems integration (levels b and c). General requisites towards the design and implementation of IPM programs are outlined.
Host plant finding in phytophagous insects: the case of the Colorado potato beetle
Authors: Jermy Tibor , Szentesi Árpád , Horváth Judit
Published: November 2011

A short critical review is given on the literature of host plant finding in phytophagous insects with main emphasis on the Colorado potato beetle (Leptinotarsa decemlineata Say, col.: Chrysomelidae). The literature data are compared with the results of field experiments: (1) the foraging behaviour of adults was observed in a field arena on bare ground, and (2) adults were released in closed plant stands and recaptured by potted potato plants. It is concluded that host plant finding is a chance event in this species. The observed high directionality of move must be an adaptation increasing probability of host finding. Implications on population dynamics and agricultural practice are discussed.
Conflicting or Compatible: Beliefs About Religion and Science Among Emerging Adults in the United States1
Authors: Longest Kyle C. , Smith Christian
Published: November 2011

A wide‐held assumption is that increased religiousness is associated with stronger perceptions of a conflict between religion and science. This article examines this assumption using four distinct questions asked on the third wave of the National Study of Youth and Religion (NSYR). Results indicate a variety of viewpoints for constructing the relationship between science and religion, rather than a simple conflict‐compatibility continuum. Further, findings suggest that increased religiousness among emerging adults is associated with a stronger agreement in science and religion’s compatibility, rather than conflict. Incorporating New Age or non‐Western spiritual tradition and a strict adherence to fundamentalist Christian doctrine are associated with complex configurations of beliefs on the relationship between religion and science. Collectively, the findings among emerging adults contradict traditional assumptions about how religious experiences influence beliefs, suggesting that such social factors may influence beliefs and attitudes uniquely at different points in the lifecourse or across generations. More broadly, the findings speak to the ongoing debate about the extent to which differing social experiences may produce consistent or discordant sets of beliefs and values, and in turn how particular configurations may impact strategies of action across a range of life domains.
Review of the East Asian species of the genera Hybrizon Fallén and Ghilaromma Tobias (Hymenoptera: Ichneumonidae: Hybrizontinae)
Authors: KONISHI Kazuhiko , CHOI Moon‐Bo , LEE Jong‐Wook
Published: November 2011

East Asian species of the genera Hybrizon and Ghilaromma are reviewed. Four species of Hybrizon, H. buccatus (Brébisson 1825), H. ghilarovi Tobias, 1988, H. juncoi (Ceballos 1957) and H. flavofacialis Tobias, 1988 and two species of Ghilaromma, G. orientalis Tobias, 1988 and G. ussuriensis Tobias, 1988, were recognized. H. ghilarovi was recorded from Korea, Japan and China, while H. juncoi was recorded from Korea, for the first time. The specimens recorded from Japan as G. fuliginosi (Wilkinson, 1930) by Watanabe (1984) are referred to G. orientalis herein. This species is newly recorded from Korea and Japan. Keys to East Asian species of Hybrizon and the world species of Ghilaromma are also provided.
Astrocyte and Macrophage Regulation of YKL‐40 Expression and Cellular Response in Neuroinflammation
Authors: Bonneh‐Barkay Dafna , Bissel Stephanie J. , Kofler Julia , Starkey Adam , Wang Guoji , Wiley Clayton A.
Published: November 2011

Numerous inflammatory conditions are associated with elevated YKL‐40 expression by infiltrating macrophages. Thus, we were surprised to observe minimal macrophage and abundant astrocyte expression of YKL‐40 in neuroinflammatory conditions. The aims of the current study were to better delineate this discrepancy, characterize the factors that regulate YKL‐40 expression in macrophages and astrocytes and study whether YKL‐40 expression correlates with cell morphology and/or activation state. In vitro, macrophages expressed high levels of YKL‐40 that was induced by classical activation and inhibited by alternative activation. Cytokines released from macrophages induced YKL‐40 transcription in astrocytes that was accompanied by morphological changes and altered astrocytic motility. Because coculturing of astrocytes and macrophages did not reverse this in vitro expression pattern, additional components of the in vivo central nervous system (CNS) milieu must be required to suppress macrophage and induce astrocyte expression of YKL‐40.
Robust Design of Horizontal Axis Wind Turbines Using Taguchi Method
Authors: Hu Yi , Rao Singiresu S.
Published: November 2011

The robust design of horizontal axis wind turbines, including both parameter design and tolerance design, is presented. A simple way of designing robust horizontal axis wind turbine systems under realistic conditions is outlined with multiple design parameters (variables), multiple objectives, and multiple constraints simultaneously by using the traditional Taguchi method and its extensions. The performance of the turbines is predicted using the axial momentum theory and the blade element momentum theory. In the parameter design stage, the energy output of the turbine is maximized using the Taguchi method and an extended penalty-based Taguchi method is proposed to solve constrained parameter design problems. The results of the unconstrained and constrained parameter design problems, in terms of the objective function and constraints are compared. Using an appropriate set of tolerance settings of the parameters, the tolerance design problem is formulated so as to yield an economical design, while ensuring a minimal variability in the performance of the wind turbine. The resulting multi-objective tolerance design problem is solved using the traditional Taguchi method. The present work provides a simple and economical approach for the robust optimal design of horizontal axis wind turbines.
A Design Preference Elicitation Query as an Optimization Process
Authors: Ren Yi , Papalambros Panos Y.
Published: November 2011

We seek to elicit individual design preferences through human-computer interaction. During an iteration of the interactive session, the computer queries the subject by presenting a set of designs from which the subject must make a choice. The computer uses this choice feedback and creates the next set of designs using knowledge accumulated from previous choices. Under the hypothesis that human responses are deterministic, we discuss how query schemes in the elicitation task can be viewed mathematically as learning or optimization algorithms. Two query schemes are defined. Query type 1 considers the subject’s binary choices as definite preferences, i.e., only preferred designs are chosen, while others are skipped; query type 2 treats choices as comparisons among a set, i.e., preferred designs are chosen relative to those in the current set but may be dropped in future iterations. We show that query type 1 can be considered as an active learning problem, while type 2 as a “black-box” optimization problem. This paper concentrates on query type 2. Two algorithms based on support vector machine and efficient global optimization search are presented and discussed. Early user tests for vehicle exterior styling preference elicitation are also presented.
Detection of Pristine Gas Two Billion Years After the Big Bang
Authors: Fumagalli Michele , O'Meara John M. , Prochaska J. Xavier
Published: November 2011

Two cosmic clouds have been observed with a composition close to that of the universe before the first stars were formed.
Capnocytophaga Lung Abscess in a Patient with Metastatic Neuroendocrine Tumor
Authors: Thirumala Raghu , Rappo Urania , Babady N. Esther , Kamboj Mini , Chawla Mohit
Published: November 2011

Capnocytophaga
species are known commensals of the oral cavity of humans and animals (mainly dogs and cats) and are a rare cause of respiratory tract infections. We report a case of cavitary lung abscess caused by a
Capnocytophaga
species in a patient with a metastatic neuroendocrine tumor.
TWIST-THREE DISTRIBUTION f⊥(x, k⊥) IN LIGHT-FRONT HAMILTONIAN APPROACH
Authors: MUKHERJEE A. , KORRAPATI R.
Published: November 2011

We calculate the twist-three distribution f⊥(x, k⊥) contributing to Cahn effect in unpolarized semi-inclusive deep inelastic scattering. We use light-front Hamiltonian technique and take the state to be a dressed quark at one-loop in perturbation theory. The "genuine twist-three" contribution comes from the quark–gluon interaction part in the operator and is explicitly calculated. f⊥(x, k⊥) is compared with f1(x, k⊥).
LIE 3-ALGEBRA AND SUPER-AFFINIZATION OF SPLIT-OCTONIONS
Authors: CARRIÓN HECTOR L. , GIARDINO SERGIO
Published: November 2011

The purpose of this study is to extend the concept of a generalized Lie 3-algebra, known to the divisional algebra of the octonions 𝕆, to split-octonions 𝕊𝕆, which is non-divisional. This is achieved through the unification of the product of both of the algebras in a single operation. Accordingly, a notational device is introduced to unify the product of both algebras. We verify that 𝕊𝕆 is a Malcev algebra and we recalculate known relations for the structure constants in terms of the introduced structure tensor. Finally we construct the manifestly supersymmetric [Formula: see text] affine superalgebra. An application of the split Lie 3-algebra for a Bagger and Lambert gauge theory is also discussed.
Lipids promote survival, proliferation, and maintenance of differentiation of rat liver sinusoidal endothelial cells in vitro
Authors: Hang Ta-Chun , Lauffenburger Douglas A. , Griffith Linda G. , Stolz Donna B.
Published: November 2011

Primary rat liver sinusoidal endothelial cells (LSEC) are difficult to maintain in a differentiated state in culture for scientific studies or technological applications. Relatively little is known about molecular regulatory processes that affect LSEC differentiation because of this inability to maintain cellular viability and proper phenotypic characteristics for extended times in vitro, given that LSEC typically undergo death and detachment around 48–72 h even when treated with VEGF. We demonstrate that particular lipid supplements added to serum-free, VEGF-containing medium increase primary rat liver LSEC viability and maintain differentiation. Addition of a defined lipid combination, or even oleic acid (OA) alone, promotes LSEC survival beyond 72 h and proliferation to confluency. Moreover, assessment of LSEC cultures for endocytic function, CD32b surface expression, and exhibition of fenestrae showed that these differentiation characteristics were maintained when lipids were included in the medium. With respect to the underlying regulatory pathways, we found lipid supplement-enhanced phosphatidylinositol 3-kinase and MAPK signaling to be critical for ensuring LSEC function in a temporally dependent manner. Inhibition of Akt activity before 72 h prevents growth of SEC, whereas MEK inhibition past 72 h prevents survival and proliferation. Our findings indicate that OA and lipids modulate Akt/PKB signaling early in culture to mediate survival, followed by a switch to a dependence on ERK signaling pathways to maintain viability and induce proliferation after 72 h. We conclude that free fatty acids can support maintenance of liver LSEC cultures in vitro; key regulatory pathways involved include early Akt signaling followed by ERK signaling.
Validation of Genetic Sequence Variants as Prognostic Factors in Early-Stage Head and Neck Squamous Cell Cancer Survival
Authors: Azad Abul Kalam , Bairati Isabelle , Samson Elodie , Cheng Dangxiao , Mirshams Maryam , Qiu Xin , Savas Sevtap , Waldron John , Wang Changshu , Goldstein David , Xu Wei , Meyer Francois , Liu Geoffrey
Published: November 2011

Purpose: From the published literature, we identified 23 germ line sequence variants in 17 genes from hypothesis-generating studies that were associated with prognosis of head and neck cancer, including sequence variants of DNA repair (ERCC1, ERCC4, ERCC5, MSH2, XPA, ERCC2, XRCC1, XRCC3), DNA methylation (DNMT3B), cell cycle and proliferation (CCND1, TP53), xenobiotic metabolism (GSTM1, GSTT1, CYP2D6), metastatic -potential (MMP3), immunologic (CTLA4), and growth factor pathways (FGFR4). The purpose of this study was to validate the role of these 23 sequence variants for overall (OS) and disease-free survival (DFS) in a large, comprehensive, well-annotated data set of patients with head and neck cancer.

Experimental Design: We genotyped these sequence variants in 531 patients with stage I and II radiation-treated head and neck cancer (originally recruited for an alpha-tocopherol/beta-carotene placebo-controlled secondary prevention study), and analyzed using Cox proportional hazards models, stratified by treatment arm, adjusting for clinical prognostic factors.

Results: Two OS associations were statistically significant for each variant allele when compared with the wild-type: CTLA4: A49G [rs231775; adjusted HR (aHR), 1.32 (1.1–1.6); P = 0.01] and XRCC1: Arg339Gln [rs25487; aHR, 1.28 (1.05–1.57); P = 0.02]. Both of these sequence variants had significant results in the opposite direction as prior published literature. Two DFS associations were of borderline significance in the same direction as prior literature: ERCC2: Lys751Gln [rs13181; aHR, 0.80 (0.6–1.0); P = 0.05] and TP53: Arg72Pro [rs1042522; aHR, 1.28 (1.0–1.6); P = 0.03], comparing number of variant alleles with reference of zero variants.

Conclusions: None of the prognostic sequence variants previously published was validated for OS in our patients with early-stage radiation-treated head and neck cancer, though rs1381and rs1042522 had borderline significant association with DFS. Clin Cancer Res; 18(1); 196–206. ©2011 AACR.
The Association of CD46, SLAM and CD209 Cellular Receptor Gene SNPs with Variations in Measles Vaccine-Induced Immune Responses: A Replication Study and Examination of Novel Polymorphisms
Authors: Ovsyannikova Inna G. , Haralambieva Iana H. , Vierkant Robert A. , O’Byrne Megan M. , Jacobson Robert M. , Poland Gregory A.
Published: November 2011

Background: The measles virus (MV) interacts with two known cellular receptors: CD46 and SLAM. The transmembrane receptor CD209 interacts with MV and augments dendritic cell infection. Methods: 764 subjects previously immunized with measles-mumps-rubella vaccine were genotyped for 66 candidate SNPs in the CD46, SLAM and CD209 genes as part of a larger study. Results: A previously detected association of the CD46 SNP rs2724384 with measles-specific antibodies was successfully replicated in this study. Increased representation of the minor allele G for an intronic CD46 SNP was associated with an allele dose-related decrease (978 vs. 522 mIU/ml, p = 0.0007) in antibody levels. This polymorphism rs2724384 also demonstrated associations with IL-6 (p = 0.02), IFN-α (p = 0.007) and TNF-α (p = 0.0007) responses. Two polymorphisms (coding rs164288 and intronic rs11265452) in the SLAM gene that were associated with measles antibody levels in our previous study were associated with IFN-γ Elispot (p = 0.04) and IL-10 responses (p = 0.0008), respectively, in this study. We found associations between haplotypes, AACGGAATGGAAAG (p = 0.009) and GGCCGAGAGGAGAG (p < 0.001), in the CD46 gene and TNF-α secretion. Conclusion: Understanding the functional and mechanistic consequences of these genetic polymorphisms on immune response variations could assist in directing new measles and potentially other viral vaccine design, and in better understanding measles immunogenetics.
Synergistic Effect between BRAP Polymorphism and Diabetes on the Extent of Coronary Atherosclerosis in the Chinese Population
Authors: Hsu Po-Chao , Lin Tsung-Hsien , Su Ho-Ming , Juo Suh-Hang Hank , Lai Wen-Ter , Sheu Sheng-Hsiung
Published: November 2011

Objectives: Coronary artery disease (CAD) is a multifactorial disease and influenced by genetics. We previously reported that a single nucleotide polymorphism (rs11066001) in the BRAP gene was related to the risk of myocardial infarction. However, it is unclear whether rs11066001 is associated with the extent of coronary atherosclerosis. Methods: We enrolled 732 patients scheduled for diagnostic coronary angiography. Angiographic presence of significant CAD (0 or 1), clinical vessel score (CVS, 0–3 vessels) and diffuse score (DS, 0–11.5) were used to evaluate the extent of coronary atherosclerosis. Genotyping was carried out by the TaqMan technology. Results: Of all patients, 558 (76.2%) had significant CAD. The odds ratio for the GG to the AA genotype was 2.45 (95% CI 1.13–5.34, p = 0.024) for the presence of significant CAD. The CVS was correlated with the frequency of genotypes in the recessive model (p = 0.001). Regression analysis showed a significant association between rs11066001 and the presence of significant CAD and DS (all p < 0.05). There was a synergistic effect between rs11066001 and diabetes on the occurrence of significant CAD (p < 0.001 for interaction). Conclusion: The BRAP rs11066001 gene is associated with the extent of coronary atherosclerosis and has a synergistic effect with diabetes on the occurrence of significant CAD in the Chinese population.
Rap1-Rac1 Circuits Potentiate Platelet Activation
Authors: Stefanini Lucia , Boulaftali Yacine , Ouellette Timothy D. , Holinstat Michael , Désiré Laurent , Leblond Bertrand , Andre Patrick , Conley Pamela B. , Bergmeier Wolfgang
Published: November 2011

Objective—

The goal of this study was to investigate the potential crosstalk between Rap1 and Rac1, 2 small GTPases central to platelet activation, particularly downstream of the collagen receptor GPVI.

Methods and Results—

We compared the activation response of platelets with impaired Rap signaling (double knock-out; deficient in both the guanine nucleotide exchange factor, CalDAG-GEFI, and the Gi-coupled receptor for ADP, P2Y12), to that of wild-type platelets treated with a small-molecule Rac inhibitor, EHT 1864 (wild-type /EHT). We found that Rac1 is sequentially activated downstream of Rap1 on stimulation via GPVI. In return, Rac1 provides important feedback for both CalDAG-GEFI– and P2Y12-dependent activation of Rap1. When analyzing platelet responses controlled by Rac1, we observed (1) impaired lamellipodia formation, clot retraction, and granule release in both double knock-out and EHT 1864-treated wild-type platelets; and (2) reduced calcium store release in EHT 1864-treated wild-type but not double knock-out platelets. Consistent with the latter finding, we identified 2 pools of Rac1, one activated immediately downstream of GPVI and 1 activated downstream of Rap1.

Conclusion—

We demonstrate important crosstalk between Rap1 and Rac1 downstream of GPVI. Whereas Rap1 signaling directly controls sustained Rac1 activation, Rac1 affects CalDAG-GEFI– and P2Y12-dependent Rap1 activation via its role in calcium mobilization and granule/ADP release, respectively.
Response of Blood Pressure and Blood Glucose to Treatment With Recombinant Tissue-Type Plasminogen Activator in Acute Ischemic Stroke
Authors: Kerr Daniel M. , Fulton Rachael L. , Higgins Peter , Bath Philip M.W. , Shuaib Ashfaq , Lyden Patrick , Lees Kennedy R. ,   for the VISTA Collaborators*
Published: November 2011

Background and Purpose—

Elevations in blood pressure (BP) and blood glucose are common during stroke and may represent a stress response secondary to the acute neurological deficit. If so, they should settle more completely in recombinant tissue-type plasminogen activator (rtPA)-treated patients in association with improved neurological status.

Methods—

We performed a controlled comparison of 24-hour declines in BP and glucose in rtPA-treated and control patients from the Virtual Stroke International Stroke Trial Archive (VISTA) database. Twenty-four-hour falls in BP and glucose were compared using multiple regression to account for baseline imbalances. The logarithmic transformation of glucose was used and 24-hour differences expressed as ratios of 24 hours to admission geometric means. Two-way analysis of variance was used to test for interaction between rtPA and early improvement for 24-hour falls in BP and blood glucose.

Results—

BP analysis included 5406 patients (rtPA=41%) and glucose analysis 4288 (rtPA=37%). rtPA-treated patients were younger, less likely to have a history of hypertension or diabetes, and had more severe strokes on admission. BP and glucose were lower at baseline in rtPA-treated patients than control subjects. On regression, rtPA predicted significantly greater 24-hour falls in systolic BP (β=3.9; 95% CI, 2.8–5.0), diastolic BP (β=3.1; 95% CI, 2.4–3.9), and glucose (β=0.97; 95% CI, 0.95–0.99). rtPA did not interact with early neurological improvement for 24-hour falls in systolic BP (
P
=0.72), diastolic BP (
P
=0.79), or blood glucose (
P
=0.51).

Conclusions—

A stress response does not appear to be the principal cause of elevations in BP and glucose during stroke.
Concurrent Validity and Reliability of Retrospective Scoring of the Pediatric National Institutes of Health Stroke Scale
Authors: Beslow Lauren A. , Kasner Scott E. , Smith Sabrina E. , Mullen Michael T. , Kirschen Matthew P. , Bastian Rachel A. , Dowling Michael M. , Lo Warren , Jordan Lori C. , Bernard Timothy J. , Friedman Neil , deVeber Gabrielle , Kirton Adam , Abraham Lisa , Licht Daniel J. , Jawad Abbas F. , Ellenberg Jonas H. , Lautenbach Ebbing , Ichord Rebecca N.
Published: November 2011

Background and Purpose—

The Pediatric National Institutes of Health Stroke Scale (PedNIHSS), an adaptation of the adult National Institutes of Health Stroke Scale, is a quantitative measure of stroke severity shown to be reliable when scored prospectively. The ability to calculate the PedNIHSS score retrospectively would be invaluable in the conduct of observational pediatric stroke studies. The study objective was to assess the concurrent validity and reliability of estimating the PedNIHSS score retrospectively from medical records.

Methods—

Neurological examinations from medical records of 75 children enrolled in a prospective PedNIHSS validation study were photocopied. Four neurologists of varying training levels blinded to the prospective PedNIHSS scores reviewed the records and retrospectively assigned PedNIHSS scores. Retrospective scores were compared among raters and to the prospective scores.

Results—

Total retrospective PedNIHSS scores correlated highly with total prospective scores (
R
2
=0.76). Interrater reliability for the total scores was “excellent” (intraclass correlation coefficient, 0.95; 95% CI, 0.94–0.97). Interrater reliability for individual test items was “substantial” or “excellent” for 14 of 15 items.

Conclusions—

The PedNIHSS score can be scored retrospectively from medical records with a high degree of concurrent validity and reliability. This tool can be used to improve the quality of retrospective pediatric stroke studies.
Aortic Stiffness Predicts Functional Outcome in Patients After Ischemic Stroke
Authors: Gąsecki Dariusz , Rojek Agnieszka , Kwarciany Mariusz , Kubach Marlena , Boutouyrie Pierre , Nyka Walenty , Laurent Stephane , Narkiewicz Krzysztof
Published: November 2011

Background and Purpose—

Increased aortic stiffness (measured by carotid–femoral pulse wave velocity) and central augmentation index have been shown to independently predict cardiovascular events, including stroke. We studied whether pulse wave velocity and central augmentation index predict functional outcome after ischemic stroke.

Methods—

In a prospective study, we enrolled 99 patients with acute ischemic stroke (age 63.7±12.4 years, admission National Institutes of Health Stroke Scale score 6.6±6.6, mean±SD). Carotid–femoral pulse wave velocity and central augmentation index (SphygmoCor) were measured 1 week after stroke onset. Functional outcome was evaluated 90 days after stroke using the modified Rankin Scale with modified Rankin Scale score of 0 to 1 considered an excellent outcome.

Results—

In univariate analysis, low carotid–femoral pulse wave velocity (
P
=0.000001) and low central augmentation index (
P
=0.028) were significantly associated with excellent stroke outcome. Age, severity of stroke, presence of previous stroke, diabetes, heart rate, and peripheral pressures also predicted stroke functional outcome. In multivariate analysis, the predictive value of carotid–femoral pulse wave velocity (<9.4 m/s) remained significant (OR, 0.21; 95% CI, 0.06–0.79;
P
=0.02) after adjustment for age, National Institutes of Health Stroke Scale score on admission, and presence of previous stroke. By contrast, central augmentation index had no significant predictive value after adjustment.

Conclusions—

This study indicates that aortic stiffness is an independent predictor of functional outcome in patients with acute ischemic stroke.
Sensitivity of Idealized Squall-Line Simulations to the Level of Complexity Used in Two-Moment Bulk Microphysics Schemes
Authors: Van Weverberg Kwinten , Vogelmann Andrew M. , Morrison Hugh , Milbrandt Jason A.
Published: November 2011

This paper investigates the level of complexity that is needed within bulk microphysics schemes to represent the essential features associated with deep convection. To do so, the sensitivity of surface precipitation is evaluated in two-dimensional idealized squall-line simulations with respect to the level of complexity in the bulk microphysics schemes of H. Morrison et al. and of J. A. Milbrandt and M. K. Yau. Factors examined include the number of predicted moments for each of the precipitating hydrometeors, the number and nature of ice categories, and the conversion term formulations. First, it is shown that simulations of surface precipitation and cold pools are not only a two-moment representation of rain, as suggested by previous research, but also by two-moment representations for all precipitating hydrometeors. Cold pools weakened when both rain and graupel number concentrations were predicted, because size sorting led to larger graupel particles that melted into larger raindrops and caused less evaporative cooling. Second, surface precipitation was found to be less sensitive to the nature of the rimed ice species (hail or graupel). Production of hail in experiments including both graupel and hail strongly depends on an unphysical threshold that converts small hail back to graupel, indicating the need for a more physical treatment of the graupel-to-hail conversion. Third, it was shown that the differences in precipitation extremes between the two-moment microphysics schemes are mainly related to the treatment of drop breakup. It was also shown that, although the H. Morrison et al. scheme is dominated by deposition growth and low precipitation efficiency, the J. A. Milbrandt and M. K. Yau scheme is dominated by riming processes and high precipitation efficiency.
Lateral spreading of a fiber bundle via mechanical means
Authors: Irfan M. S. , Machavaram V. R. , Mahendran R. S. , Shotton-Gale N. , Wait C. F. , Paget M. A. , Hudson M. , Fernando G. F.
Published: November 2011

In the current study, the model, previously developed by Wilson, was reviewed and extended to predict the mechanically induced spreading of E-glass fiber bundles. The widths of the as-received E-glass fiber bundles were increased by 200–250% when subjected to a series of reciprocating motions. A 350–450% increase in the widths of the bundles was observed when the tension was released (tension-release mechanism) and the reciprocating motions repeated. The effect of the number of rods, angles and distances between them, and their relative geometry on the extent of fiber spreading was studied. The forces involved in fiber spreading are discussed using micro-mechanics involved in the fiber spreading.