bluuebunny/crossref_metadata_2025_split huggingface dataset:
Definition of a Conserved Immunodominant Domain on Hepatitis C Virus E2 Glycoprotein by Neutralizing Human Monoclonal Antibodies
Authors: Keck Zhen-Yong , Li Ta-Kai , Xia Jinming , Gal-Tanamy Meital , Olson Oakley , Li Sophia H. , Patel Arvind H. , Ball Jonathan K. , Lemon Stanley M. , Foung Steven K. H. 
Published: April 2008

ABSTRACT
Development of a successful hepatitis C virus (HCV) vaccine requires the definition of neutralization epitopes that are conserved among different HCV genotypes. Five human monoclonal antibodies (HMAbs) are described that cross-compete with other antibodies to a cluster of overlapping epitopes, previously designated domain B. Each HMAb broadly neutralizes retroviral pseudotype particles expressing HCV E1 and E2 glycoproteins, as well as the infectious chimeric genotype 1a and genotype 2a viruses. Alanine substitutions of residues within a region of E2 involved in binding to CD81 showed that critical E2 contact residues involved in the binding of representative antibodies are identical to those involved in the binding of E2 to CD81.
Functional and Structural Dynamics of Hepadnavirus Reverse Transcriptase during Protein-Primed Initiation of Reverse Transcription: Effects of Metal Ions
Authors: Lin Li , Wan Fen , Hu Jianming 
Published: April 2008

ABSTRACT

Reverse transcription in hepadnaviruses is primed by the viral reverse transcriptase (RT) (protein priming) and requires the interaction between the RT and a specific viral RNA template termed ε. Protein priming is resistant to a number of RT inhibitors that can block subsequent viral DNA elongation and likely requires a distinct “priming” conformation. Furthermore, protein priming may consist of two distinct stages, i.e., the attachment of the first deoxynucleotide to RT (initiation) and the subsequent addition of 2 or 3 deoxynucleotides (polymerization). In particular, a truncated duck hepatitis B virus RT (MiniRT2) is competent in initiation but defective in polymerization when tested in the presence of Mg
2+
. Given the known effects of metal ions on the activities of various DNA and RNA polymerases, we tested if metal ions could affect hepadnavirus RT priming. We report here that Mn
2+
, in comparison with Mg
2+
, showed dramatic effects on the priming activity of MiniRT2 as well as the full-length RT. First and foremost, MiniRT2 exhibited full polymerization activity in the presence of Mn
2+
, indicating that MiniRT2 contains all sequences essential for polymerization but is unable to transition from initiation to polymerization with Mg
2+
. Second, the initiation activities of MiniRT2 and the full-length RT were much stronger with Mn
2+
. Third, the nucleotide and template specificities during protein priming were decreased in the presence of Mn
2+
. Fourth, polymerization was sensitive to inhibition by a pyrophosphate analog in the presence of Mn
2+
but not in the presence of Mg
2+
. Finally, limited proteolysis provided direct evidence that the priming active MiniRT2 adopted distinct conformations depending on the presence of Mn
2+
versus that of Mg
2+
and that the transition from initiation to polymerization was accompanied by RT conformational change.
Drinking policies and exercise-associated hyponatraemia: is anyone still promoting overdrinking?
Authors: Beltrami F G , Hew-Butler T , Noakes T D 
Published: April 2008

Objectives:The purpose of this review is to describe the evolution of hydration research and advice on drinking during exercise from published scientific papers, books and non-scientific material (advertisements and magazine contents) and detail how erroneous advice is likely propagated throughout the global sports medicine community.Design:Hydration advice from sports-linked entities, the scientific community, exercise physiology textbooks and non-scientific sources was analysed historically and compared with the most recent scientific evidence.Conclusions:Drinking policies during exercise have changed substantially throughout history. Since the mid-1990s, however, there has been an increase in the promotion of overdrinking by athletes. While the scientific community is slowly moving away from “blanket” hydration advice in which one form of advice fits all and towards more modest, individualised, hydration guidelines in which thirst is recognised as the best physiological indicator of each subject’s fluid needs during exercise, marketing departments of the global sports drink industry continue to promote overdrinking.
Sprayed glass fibre reinforced polymer masonry columns under concentric and eccentric loadingThis article is one of a selection of papers published in this Special Issue on Masonry.
Authors: Shaheen E. , Shrive N. G. 
Published: April 2008

Strengthening masonry columns by spraying them with glass fibre reinforced polymer (GFRP) was investigated experimentally. The study was aimed at assessing the strength and strain increases imparted by the technique under both concentric and eccentric axial loading. Plain and steel-reinforced columns were tested. Twenty-four columns were constructed from Type S mortar and straight and bullnose clay masonry units. The columns were 1 m high and either 290 mm × 290 mm or 390 mm × 390 mm in cross section. Two thicknesses of sprayed GFRP (SGFRP) were attempted, but it was found to be difficult to maintain uniform thickness. Nevertheless, with only minor increases in strength, large increases in strain capacity were achieved with both the plain and reinforced columns under concentric axial compression. Eccentric loading reduced the effect of the SGFRP laminate on the strength of masonry columns. Failure of SGFRP included both mode I and mode III fractures.
Dry-cast concrete masonry products: properties and durabilityThis article is one of a selection of papers published in this Special Issue on Masonry.
Authors: Chidiac S. E. , Zibara H. 
Published: April 2008

Performance of dry-cast concrete masonry products (DCCMPs), which are becoming the product of choice for many applications, has yet to be assessed in a comprehensive manner. This study was undertaken to investigate the effects of mix design and manufacturing parameters on the mechanical and transport properties, as well as the freeze–thaw (F/T) durabilities, of DCCMPs. The variables studied were water to cement ratio, mixing time, vibration time, and curing regime. Freeze–thaw durability was assessed in accordance with the American Society for Testing and Materials (ASTM) standard C1262 by exposing specimens to four conditions: water, 3% NaCl, 4% CaCl2, and 4% MgCl2 solutions. Results revealed that 3% NaCl exposure yielded the most mass loss due to scaling, whereas 4% MgCl2 exposure exhibited the least. Increase in either water content, vibration time, mixing time, or use of moist curing led to improvement in the mechanical properties, refinement of large pores in the range of 40 to 400 μm, reduction of total porosity, and enhancement of F/T durability of capstones. Ionic sorptivity yielded a strong statistical correlation with mass loss due to F/T action in the presence of 3% NaCl and 4% CaCl2.
Hyperphosphorylated Cortactin in Cancer Cells Plays an Inhibitory Role in Cell Motility
Authors: Jia Lin , Uekita Takamasa , Sakai Ryuichi 
Published: April 2008

Abstract
Cortactin is frequently overexpressed in cancer cells, and changes of the levels of its tyrosine phosphorylation have been observed in several cancer cells. However, how the expression level and phosphorylation state of cortactin would influence the ultimate cellular function of cancer cells is unknown. In this study, we analyzed the role of cortactin in gastric and breast cancer cell lines using RNA interference technique and found that knockdown of cortactin inhibited cell migration in a subset of gastric cancer cells with a lower level of its tyrosine phosphorylation, whereas it greatly enhanced cell migration and increased tyrosine phosphorylation of p130Cas in other subsets of cells with hyperphosphorylated cortactin. Consistent results were obtained when hyperphosphorylation of cortactin was induced in MCF7 breast cancer cells by expressing Fyn tyrosine kinase. Additionally, immunostaining analysis showed that knockdown of hyperphosphorylated cortactin resulted in the recruitment of p130Cas to focal adhesions. These results suggest that cortactin hyperphosphorylation suppresses cell migration possibly through the inhibition of membrane localization and tyrosine phosphorylation of p130Cas. (Mol Cancer Res 2008;6(4):654–62)
Vascular Endothelial Growth Factor Stimulates Organ-Specific Host Matrix Metalloproteinase-9 Expression and Ovarian Cancer Invasion
Authors: Belotti Dorina , Calcagno Catia , Garofalo Angela , Caronia Daniela , Riccardi Elena , Giavazzi Raffaella , Taraboletti Giulia 
Published: April 2008

AbstractVascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMP) regulate each other, contributing to tumor progression. We have previously reported that MMP9 induces the release of tumor VEGF, promoting ascites formation in human ovarian carcinoma xenografts. The aim of this study was to investigate whether tumor-derived VEGF regulated the expression of gelatinase by the stroma, influencing the invasive properties of ovarian tumors. Tumor variants derived from 1A9 human ovarian carcinoma, stably expressing VEGF121 in the sense (1A9-VS-1) and antisense orientations (1A9-VAS-3), were used. In vivo, zymographic analysis of tumors from 1A9-VS-1 implanted in the peritoneal cavity of nude mice showed higher levels of gelatinases, particularly murine MMP9, indicating that VEGF stimulates host expression of the matrix-degrading enzyme. Murine MMP9 expression was also high in the ovaries of mice bearing 1A9-VS-1 tumors. The effect on host MMP9 activity was organ-specific. The levels of host pro-MMP9 in ovaries correlated with the plasma levels of tumor VEGF and with the selective invasion of the ovaries. Induction of host MMP9 expression in tumors and ovaries was independent of the site of tumor growth as it was seen in mice carrying both intraperitoneal and subcutaneous tumors. The anti-VEGF antibody bevacizumab (Avastin) inhibited MMP9 expression and tumor invasion in the ovaries of mice bearing 1A9-VS-1 tumors. These findings point to a complex cross-talk between VEGF and MMPs in the progression of ovarian tumor and suggest the possibility of using VEGF inhibitors to affect MMP-dependent tumor invasion. (Mol Cancer Res 2008;6(4):525–34)
DNA Damage Responses: Mechanisms and Roles in Human Disease
Authors: Kastan Michael B. 
Published: April 2008

Abstract
Significant progress has been made in recent years in elucidating the molecular controls of cellular responses to DNA damage in mammalian cells. Much of our understanding of the mechanisms involved in cellular DNA damage response pathways has come from studies of human cancer susceptibility syndromes that are altered in DNA damage responses. Ataxia-telangiectasia mutated (ATM), the gene mutated in the disorder ataxia-telangiectasia, codes for a protein kinase that is a central mediator of responses to DNA double-strand breaks (DSB) in cells. Once activated, ATM phosphorylates numerous substrates in the cell that modulate the response of the cell to the DNA damage. We recently developed a novel system to create DNA DSBs at defined endogenous sites in the human genome and used this system to detect protein recruitment and loss at and around these breaks by chromatin immunoprecipitation. Results from this system showed the functional importance of ATM kinase activity and phosphorylation in the response to DSBs and supported a model in which ordered chromatin structure changes that occur after DNA breakage and that depend on functional NBS1 and ATM facilitate DNA DSB repair. Insights about these pathways provide us with opportunities to develop new approaches to benefit patients. Examples and opportunities for developing inhibitors that act as sensitizers to chemotherapy or radiation therapy or activators that could improve responses to cellular stresses, such as oxidative damage, are discussed. Relevant to the latter, we have shown benefits of an ATM activator in disease settings ranging from metabolic syndrome to cancer prevention. (Mol Cancer Res 2008;6(4):517–24)
Keratohyalin-like granules in embryonic and regenerating epidermis of lizards and Sphenodon punctatus (Reptilia, Lepidosauria)
Authors: Alibardi Lorenzo 
Published: April 2008

AbstractEpidermal shedding in lepidosaurians is determined by the formation of an intraepidermal shedding complex, made of an upper clear layer which interdigitates with a lower oberhautchen layer. The latter produces species-specific microornamentations. The ultrastructure of embryonic and regenerating epidermis in seven species of lizards representing five different squamate families (Gekkonidae, Agamidae, Lacertidae, Iguanidae and Scincidae), and on the regenerating caudal epidermis of the tuatara (Sphenodon punctatus, suborder Sphenodontia), has shown a broad variation in dimension and morphology of keratohyalin-like granules present in the clear layer of the shedding complex. Where the oberhautchen ornamentations are well developed, like in the setae of the climbing pads, keratohyalin-like granules appear more irregular, larger or more numerous. The present study suggests that keratohyalin-like granules might be involved in the formation of a fibrous network around the forming oberhautchen microornamentations.
A new Bolivian species of the genus Telmatobius (Anura: Leptodactylidae) with a humeral spine
Authors: Lavilla E.O. , Ergueta Sandoval Patricia 
Published: April 2008

Abstract
A new species of the genus Telmatobius is described based on two adult males from Chuspipata, Provincia Nor-Yungas, Departamento La Paz, Boliva, at 3050 m asl. This is the second species of the genus known to have an evident, externally projected humeral spine.
Phénologie de la reproduction chez Pelodytes punctatus Daudin, 1802 (Amphibia, Anura)
Authors: Guyétant R. , Temmermans W. , Avrillier J.N. 
Published: April 2008

Abstract
Pelodytes punctatus est une espèce dont les biotopes de reproduction sont localisés en plaine principalement (90% des cas). De nouvelles données sur la phénologie de la reproduction ainsi que sur le type de milieu ont été collectées durant 6 ans sur 4 régions comprenant plus de 35 sites. La période de ponte principale survient au printemps mais on peut en observer une deuxième en automne dans le sud de la France. Les œufs sont fixés en cordons par les femelles sur les tiges de plantes aquatiques. Le succès de l'éclosion dépend de l'oxygénation de l'eau. La croissance larvaire est relativement rapide en conditions contrôlées (19°C ± 1°C) et les têtards se métamorphosent 40 à 60 jours après l'éclosion. Dans le sud, deux catégories de têtards sont observées en automne, les plus petits hivernent et se métamorphosent durant le printemps suivant.
Development of testes and differentiation of germ cells in water frogs of the Rana esculenta - complex (Amphibia, Anura)
Authors: Ogielska Maria , Bartmańska Jolanta 
Published: April 2008

Abstract
The European water frog, Rana esculenta, is a hybrid whose genome is composed of haploid chromosome sets of its parental species R. lessonae and R. ridibunda. Prior to meiosis one of the parental sets is discarded and the other is duplicated (hybridogenesis). In the parental species sex differentiation begins at tadpole stages 28-30 (Gosner, 1960), at stages 30-36 the testes are composed of proliferating pale spermatogonia 1°. At stages 36-39 a new class of spermatogonia I° (dark) appears. Before first hibernation, seminiferous lobules are filled with cysts containing germ cells at various stages of spermatogenesis up to elongating spermatids. In R. esculenta gonad development is affected from the earliest stages: the gonads are smaller and composed of reduced number of spermatogonia I°. The phase of pale spermatogonia I° proliferation is prolonged up to the second year of life. The structure of the gonads, as well as that of germ cells themselves, are often abnormal.
Foraging modes in lacertid lizards from southern Africa
Authors: Cooper William E. , Whiting Martin J. 
Published: April 2008

AbstractMost lacertids are active foragers, but intrafamilial variation in foraging mode is greater than in most lizard families. We collected data on eight species of African lacertids to assess this variation. Both active and ambush foraging occurred within Pedioplanis and Meroles. Meroles ctenodactylus had a proportion of time moving and proportion of attacked prey detected while moving intermediate to those for actively foraging and ambushing Pedioplanis, but its number of movements per minute was exceptionally high. This species has a unique mixed foraging mode. Like active foragers, it seeks food by tongue-flicking while moving and spends a high percentage of the time moving. Like ambush foragers, it searches visually for prey during pauses between movements. Our findings confirm published data on four Kalahari lacertids. We discuss the history of foraging modes in advanced lacertids.
The Agonistic Behaviour of Juvenile Blennius Pholis L. (Teleostei)
Authors: Gibson R.N. 
Published: April 2008

AbstractThe agonistic behaviour of juvenile Blennius pholis, L. was observed in tanks of 28 x 43 x 30 cm and 75 x 40 x 30 cm, the larger tanks thus having a floor area 2.5 times that of the smaller tanks. The smaller tanks contained two fish, the larger ones either two or five fish. Those containing five fish thus had a population density equivalent to the smaller tanks. Eight main elements of agonistic behaviour were observed. They were; advancing, threatening, charging, snapping, fleeing, chasing, retreating and submitting. It was found that charging, fleeing, and chasing were by far the most common elements performed. Charging, threatening and chasing were performed most frequently by dominant fish, fleeing and retreating by subordinate fish. Advancing was performed more or less equally by both dominant and subordinate fish. It is suggested that submission is a displacement activity. Size difference was the main factor deciding dominance and the intensity of aggression, but the onset of light, food, available space, and the activity of the fish concerned were also of importance. The size of the tank and the number of fish it contained had an effect upon the relationship between size difference and the intensity of aggression. In the smaller tanks the intensity of aggression was directly related to the difference in size between the two fish. This relationship was not as clear in the larger tanks. Territoriality in the normally accepted sense of the word was not observed, because the fish were not seen to defend any particular area of the tank against others. A hypothesis suggesting the existence of 'individual distances' is put forward, in which the fish are considered to defend a particular area of space around themselves. These individual distances fluctuate in size according to the state of the aggressive drive of the individual and the amount of space available to it for movement. An attempt is made to relate the behaviour observed in the laboratory to that occurring in nature.
Preoptic Activation of Frog Mating Behavior
Authors: Schmidt Robert S. 
Published: April 2008

AbstractThe effects of preoptic lesions on mating calling and mate orientation were studied in Rana pipiens and several species of tree frogs (Hylidae). Mating calling was evoked by electrical stimulation of the preoptic area of Rana pipiens and Bufo americanus. A new chronic electrode holder is described. It is concluded that the region of the dorsal magnocellular preoptic nucleus is needed for mate orientation and that the region of the ventral magnocellular preoptic nucleus is needed for mating calling. It is suggested that these preoptic regions may act mainly as activators of more posterior "centers". Mating calling may have evolved through the origin of connections between pre-existing preoptic activators and a pre-existing release calling "center", rather than through the origin of a new mating calling "center".
60- to 1-Min Rainfall-Rate Conversion: Comparison of Existing Prediction Methods with Data Obtained in the Southeast Asia Region
Authors: Mandeep J. S. , Hassan S. I. S. 
Published: April 2008

AbstractRainfall-rate statistics are frequently derived on the basis of rain gauge recordings with effective integration times of 10 min or longer. The conversion of such data to equivalent statistics for an effective integration time of 1 min is very important to predict rainfall attenuation at a location accurately. Because of the limited availability of 1-min rainfall-rate data, conversion of available rainfall-rate distributions with longer integration times to the desired 1-min distributions is needed. Several methods for converting 60-min rainfall rates to 1-min rainfall rates are tested against measured rainfall rates from tropical, high-rainfall-rate regions. Segal’s method was found to perform the best overall when compared with other conversion methods.
Flood Fatalities in the United States
Authors: Ashley Sharon T. , Ashley Walker S. 
Published: April 2008

Abstract
This study compiles a nationwide database of flood fatalities for the contiguous United States from 1959 to 2005. Assembled data include the location of fatalities, age and gender of victims, activity and/or setting of fatalities, and the type of flood events responsible for each fatality report. Because of uncertainties in the number of flood deaths in Louisiana from Hurricane Katrina, these data are not included in the study. Analysis of these data reveals that a majority of fatalities are caused by flash floods. People between the ages of 10 and 29 and &gt;60 yr of age are found to be more vulnerable to floods. Findings reveal that human behavior contributes to flood fatality occurrences. These results also suggest that future structural modifications of flood control designs (e.g., culverts and bridges) may not reduce the number of fatalities nationwide. Spatially, flood fatalities are distributed across the United States, with high-fatality regions observed along the northeast Interstate-95 corridor, the Ohio River valley, and near the Balcones Escarpment in south-central Texas. The unique distributions found are likely driven by both physical vulnerabilities for flooding as well as the social vulnerabilities.
Cluster Sequencing to Analyze Synoptic Transitions Affecting Regional Ozone
Authors: Beaver Scott , Palazoglu Ahmet , Tanrikulu Saffet 
Published: April 2008

Abstract
Synoptic conditions are known to strongly influence mesoscale flows and hence local ozone levels in the San Francisco Bay Area of California. Sets of individual days sharing certain combinations of synoptic features constitute “static” meteorological patterns (or regimes) that account for much of the variability in regional ozone levels. Upon labeling each day of the core Bay Area ozone season using a small number of synoptic regimes, the resulting daily sequence of static patterns indicates the time evolution of the synoptic system through a series of regimes realized for various durations. Further insight into ozone buildup processes can be gained by examining this sequence of static labels to identify “dynamic” meteorological patterns affecting local ozone levels. Transition probabilities between each pair of synoptic regimes are modeled using binomial statistics to determine transitions that are either energetically favored or disfavored to occur. The persistency of the meteorological regimes is additionally considered to complement the transition probabilities in forming a more complete statistical characterization of the synoptic evolution. The sequencing method allows identification of two scenarios under which exceedance of air quality standards occurs in the Bay Area.