bluuebunny/crossref_metadata_2025 huggingface dataset:
Modification of cosθ coil shape in superconducting dipole magnets for reducing the coil size
Authors: Sarma P. R. , Ibomcha N. , Bhandari R. K.
Published: December 2004

In coil-dominated superconducting dipole magnets the coil size and hence the cost of the magnet can be reduced by optimizing the shape of the coil. We have used the variational calculus and a random search technique to show that the coil shape markedly deviates from the conventional cosθ design when one reduces the coil size while holding the field and field quality to specified values. A block-coil dipole giving a field of 7.0T has been designed on the basis of the optimization. With iron yoke this can give a field of 8.4T.
Use of a Joule–Thomson micro-refrigerator to cool a radio-frequency coil for magnetic resonance microscopy
Authors: Wright A. C. , Song H. K. , Elliott D. M. , Wehrli F. W.
Published: December 2004

A method is described for cryogenically cooling a rf detector coil, as used in high-resolution magnetic resonance imaging (MRI), to enhance image signal-to-noise ratio (SNR). By incorporating the rf coil into a Joule–Thomson micro-refrigerator, the coil is precision-cooled to 70K using only a source of high-pressure nitrogen gas at room temperature, avoiding the need for liquid cryogens. The rf coil is insulated by a glass vacuum dewar that permits its use in proximity to biological tissues. Design and operation of the cryogenic system are described and its performance is demonstrated in a 1.5T clinical MRI scanner with images of a water phantom and a sheep intervertebral disc specimen. SNR gains of two to three times were obtained, compared to a similar coil at room temperature. The potential of this technology for local high-resolution MRI is discussed.
Revision of the New Zealand species of Hydropeza Sinclair (Diptera : Empidoidea : Ragas-group)
Authors: Sinclair Bradley J. , McLellan Ian D.
Published: December 2004

The New Zealand species of Hydropeza Sinclair are revised and include the following ten species: H. agnetis, sp. nov., H. akatarawa, sp. nov., H. clarae, sp. nov., H. daviesi, sp. nov., H. longipennae (Miller), H. milleri, sp. nov., H. paniculata, sp. nov., H. tutoko, sp. nov., H. vockerothi, sp. nov. and H. wardi, sp. nov. All species are described and male genitalia illustrated. Adults skate about on pools and below small cascades in cool montane streams. The New Zealand fauna is divided into two groups, with the H. longipennae-group assigned as the sister-group to all remaining species of the genus. Only one species is currently known from North Island, with all remaining species confined primarily to west of the Alpine Fault in South Island. The distribution patterns in South Island are examined and implications discussed.
Influenza virus entry and infection require host cell N-linked glycoprotein
Authors: Chu Victor C. , Whittaker Gary R.
Published: December 2004

A widely held view of influenza virus infection is that the viral receptor consists of cell surface carbohydrate sialic acid, which can be present as glycoprotein or glycolipid. Here, we examined influenza virus entry and infection in Lec1 cells, a mutant CHO cell line deficient in terminal N-linked glycosylation caused by a mutation in the
N
-acetylglucosaminyltransferase I (GnT1) gene. We show that influenza virus cannot infect Lec1 cells, despite having full capacity to undergo virus binding and fusion. Lec1 cells also show no virus replication defect, and infection was restored in Lec1 cells expressing wild-type GnT1. Viruses were apparently arrested at the level of internalization from the plasma membrane and were not endocytosed. Lec1 cells were refractory to infection by several strains of influenza virus, including H1 and H3 strains of influenza A, as well as influenza B virus. Finally, cleavage of N-glycans from wild-type CHO cells markedly reduced infection by influenza virus. We suggest that influenza virus specifically requires N-linked glycoprotein for entry into cells, and that sialic acid, although acting as an efficient attachment factor, is not sufficient as an influenza virus receptor
in vivo
.
Enemy-free space maintains swallowtail butterfly host shift
Authors: Murphy Shannon M.
Published: December 2004

Natural enemies can be significant sources of mortality for herbivorous insects and therefore important agents of natural selection. One might expect selection to favor herbivores that escape from their natural enemies into enemy-free space. Although this is an appealing idea, it has received little empirical support, and no studies have documented enemy-free space as part of a nonagricultural, nonartificial host shift. The Alaskan swallowtail butterfly,Papilio machaon aliaska, uses as host plants a species in the family Apiaceae (Cnidium cnidiifolium) along with two Asteraceae species (Artemisia arcticaandPetasites frigidus). I analyzed growth and survival ofP. m. aliaskalarvae in the field on the three host plants in treatments that either exposed or protected them from predators. I found that, in the presence of predators, larval survival is greater on the novel hosts (Asteraceae) than on the ancestral host (Apiaceae), but that in the absence of predators survival and growth are greater on the ancestral host. These results are a demonstration of enemy-free space as a mechanism for maintaining a naturally occurring host shift.
Ribavirin suppresses eIF4E-mediated oncogenic transformation by physical mimicry of the 7-methyl guanosine mRNA cap
Authors: Kentsis Alex , Topisirovic Ivan , Culjkovic Biljana , Shao Ling , Borden Katherine L. B.
Published: December 2004

The eukaryotic translation initiation factor eIF4E is deregulated in many human cancers, and its overexpression in cells leads to malignant transformation. Oncogenic properties of eIF4E are directly linked to its ability to bind 7-methyl guanosine of the 5′ mRNA. Here, we observe that the antiviral guanosine analogue ribavirin binds to eIF4E with micromolar affinity at the functional site used by 7-methyl guanosine mRNA cap, competes with eIF4E:mRNA binding, and, at low micromolar concentrations, selectively disrupts eIF4E subcellular organization and transport and translation of mRNAs posttranscriptionally regulated by eIF4E, thereby reducing levels of oncogenes such as cyclin D1. Ribavirin potently suppresses eIF4E-mediated oncogenic transformation of murine cells
in vitro
, of tumor growth of a mouse model of eIF4E-dependent human squamous cell carcinoma
in vivo
, and of colony formation of eIF4E-dependent acute myelogenous leukemia cells derived from human patients. These findings describe a specific, potent, and unforeseen mechanism of action of ribavirin. Quantum mechanical and NMR structural studies offer directions for the development of derivatives with improved cytostatic and antiviral properties. In all, ribavirin's association with eIF4E may provide a pharmacologic means for the interruption of posttranscriptional networks of oncogenes that maintain and enhance neoplasia and malignancy in human cancer.
Triacylglycerol Hydrolase Is Localized to the Endoplasmic Reticulum by an Unusual Retrieval Sequence where It Participates in VLDL Assembly without Utilizing VLDL Lipids as Substrates
Authors: Gilham Dean , Alam Mustafa , Gao Wenhui , Vance Dennis E. , Lehner Richard
Published: December 2004

The majority of hepatic intracellular triacylglycerol (TG) is mobilized by lipolysis followed by reesterification to reassemble TG before incorporation into a very-low-density lipoprotein (VLDL) particle. Triacylglycerol hydrolase (TGH) is a lipase that hydrolyzes TG within hepatocytes. Immunogold electron microscopy in transfected cells revealed a disparate distribution of this enzyme within the endoplasmic reticulum (ER), with particularly intense localization in regions surrounding mitochondria. TGH is localized to the lumen of the ER by the C-terminal tetrapeptide sequence HIEL functioning as an ER retention signal. Deletion of HIEL resulted in secretion of catalytically active TGH. Mutation of HIEL to KDEL, which is the consensus ER retrieval sequence in animal cells, also resulted in ER retention and conservation of lipolytic activity. However, KDEL-TGH was not as efficient at mobilizing lipids for VLDL secretion and exhibited an altered distribution within the ER. TGH is a glycoprotein, but glycosylation is not required for catalytic activity. TGH does not hydrolyze apolipoprotein B–associated lipids. This suggests a mechanism for vectored movement of TGs onto developing VLDL in the ER as TGH may mobilize TG for VLDL assembly, but will not access this lipid once it is associated with VLDL.
A Dynamic Actin Cytoskeleton Functions at Multiple Stages of Clathrin-mediated Endocytosis
Authors: Yarar Defne , Waterman-Storer Clare M. , Schmid Sandra L.
Published: December 2004

Clathrin-mediated endocytosis in mammalian cells is critical for a variety of cellular processes including nutrient uptake and cell surface receptor down-regulation. Despite the findings that numerous endocytic accessory proteins directly or indirectly regulate actin dynamics and that actin assembly is spatially and temporally coordinated with endocytosis, direct functional evidence for a role of actin during clathrin-coated vesicle formation is lacking. Here, we take parallel biochemical and microscopic approaches to address the contribution of actin polymerization/depolymerization dynamics to clathrin-mediated endocytosis. When measured using live-cell fluorescence microscopy, disruption of the F-actin assembly and disassembly cycle with latrunculin A or jasplakinolide results in near complete cessation of all aspects of clathrin-coated structure (CCS) dynamics. Stage-specific biochemical assays and quantitative fluorescence and electron microscopic analyses establish that F-actin dynamics are required for multiple distinct stages of clathrin-coated vesicle formation, including coated pit formation, constriction, and internalization. In addition, F-actin dynamics are required for observed diverse CCS behaviors, including splitting of CCSs from larger CCSs, merging of CCSs, and lateral mobility on the cell surface. Our results demonstrate a key role for actin during clathrin-mediated endocytosis in mammalian cells.
Quantitative Trait Loci Mapping for Ethanol Sensitivity and Neurotensin Receptor Density in an F2 Intercross Derived From Inbred High and Low Alcohol Sensitivity Selectively Bred Rat Lines
Authors: Radcliffe Richard A. , Erwin V Gene , Draski Laura , Hoffmann Sarah , Edwards Joel , Deng Xin‐Sheng , Bludeau Pequita , Fay Tina , Lundquist Kristy , Asperi William , Deitrich Richard A.
Published: December 2004

Background: Genetic variance in initial sensitivity to ethanol has been implicated as a risk factor for the development of alcoholism. Identification of the genes that confer differential initial sensitivity is an important goal for the development of new treatment strategies and for a comprehensive understanding of the mechanism of ethanol's action. Quantitative trait loci (QTL) mapping for initial sensitivity and other ethanol‐related behavioral traits in model organisms has become an important first step for the ultimate identification of genes that contribute to variation in ethanol responses.

Methods: An F2 intercross was made from the Inbred High and Low Alcohol Sensitivity rat lines (IHAS and ILAS). The F2 rats were tested for duration of the loss of righting reflex test (LORR); blood ethanol concentration at regain of righting reflex (BECrrr); BEC at the first time to reach criterion on the rotarod after 1.6 g/kg of ethanol (BEC1); acute functional tolerance on the rotarod (AFT); and high‐affinity neurotensin receptor (NTR1) density in the nucleus accumbens (NAc), caudate putamen (CP), and ventral midbrain (VMB). A full genome scan with an average marker spacing of 16.8 cM for interval QTL mapping was conducted on the F2 rats (N= 363).

Results: Seven significant or suggestive QTL were detected for LORR, one for BECrrr, three for BEC1, two for NTR1 binding in the CP, and one for binding in the NAc, but none were mapped for AFT or NTR1 binding density in the VMB. Effect size of the seven LORR QTL, the trait for which the parental strains were selected, ranged from 3 to 4%, with all accounting for ∼22% of the total phenotypic variation. One of the LORR QTL on chromosome 2 (∼87 cM) was significant, and a second QTL on chromosome 5 (∼37 cM) was suggestive for both LORR and BECrrr.

Conclusions: The results indicate that segregating populations derived from the IHAS and ILAS strains can be used for mapping ethanol sensitivity QTL. The chromosome 2 LORR QTL may confer variation in ethanol metabolism, whereas the chromosome 5 LORR/BECrrr QTL likely mediates central nervous system ethanol sensitivity. The small number or absence of QTL for BEC1, AFT, and NTR1 receptor density suggests that genetic variation for these traits is minimal in the IHAS/ILAS strains and/or the effect size of QTL for these traits is too small to be mapped efficiently in this sample of F2 rats. The ultimate identification of genes underlying these alcohol sensitivity QTL will contribute to our understanding of the actions of alcohol in the central nervous system if not to a deeper understanding of the genetic risk factors for alcoholism.
Preserved Vasopressin Response to Osmostimulation Despite Decreased Basal Vasopressin Levels in Long‐Term Abstinent Alcoholics
Authors: Jahn Henriette , Döring Wolf K.H. , Krampe Henning , Sieg Sonja , Werner Carola , Poser Wolfgang , Brunner Edgar , Ehrenreich Hannelore
Published: December 2004

Background: Basal arginine vasopressin (AVP) plasma levels in alcoholic patients are persistently decreased over months of controlled alcohol abstinence. As a potential explanation of this phenomenon, a reduction of AVP immunoreactive neurons was described in the hypothalamus of alcohol‐dependent humans and rodents. This study was therefore designed to examine whether long‐term abstinent alcoholics have a compromised response of AVP to osmostimulation.

Methods: Fifteen male alcoholics, aged 42 ± 2 years, were examined (1) over 12 months of strictly controlled abstinence (longitudinal study) and (2) during an osmostimulation test (5% NaCl infusion at 0.06 ml/kg/min over 2 hr) and were compared with 15 healthy male subjects, aged 41 ± 2 years. AVP and routine laboratory parameters, including electrolytes and osmolality, were measured.

Results: Starting from lower basal concentrations, alcoholics showed increases similar to those of controls in AVP and plasma osmolality after osmostimulation. The first sensation of thirst was announced significantly later by alcoholics than by controls. Twenty‐hour‐posttest urine volume and sodium excretion were reduced in alcoholics compared with controls.

Conclusions: Despite their persistently decreased basal AVP plasma levels, long‐term abstinent alcoholics have a well preserved AVP response to osmostimulation. This finding indicates a peripheral suppression of AVP levels that is most likely due to a regulatory set‐point shift toward hypotonic hyperhydration, rather than to a reduced central capacity of AVP secretion.
Testing the Level of Response to Alcohol: Social Information Processing Model of Alcoholism Risk—A 20‐Year Prospective Study
Authors: Schuckit Marc A. , Smith Tom L. , Anderson Kristen G. , Brown Sandra A.
Published: December 2004

Background: The low level of response (LR) to alcohol is a genetically influenced characteristic associated with an enhanced risk for alcohol use disorders (AUDs). An optimal understanding of how this intermediate phenotype relates to the AUD risk requires evaluation of the milieu in which LR operates, and this study tested an LR/social information processing model in adult men.

Methods: Almost 300 Caucasian males (97% of those eligible, to date) from the San Diego Prospective Study participated in an alcohol challenge at approximately age 20 and were evaluated with a structural equation model regarding their expectations of the effects of alcohol, drinking among peers, use of alcohol to cope with stress, and alcohol‐related problems during follow‐up.

Results: The direct paths in the structural equation model in these 40‐year‐old men explained 58% of the variance of the alcoholic outcome at age 40 and 35% at age 35 while demonstrating good fitness characteristics. The LR to alcohol was related to the family history of AUDs and to the alcoholic outcome; the latter primarily operated through the use of alcohol to cope with stress. Although drinking in peers and expectations of the effects of alcohol both contributed to the model in these 40‐year‐old men, they were not directly related to LR.

Conclusions: The results continue to support the importance of the low LR to alcohol as a predictor of AUDs, even when evaluated in the context of additional relevant characteristics. Future evaluations of adolescent and young adult subjects will also explore the potential importance of expectations of the effects of alcohol and drinking among peers as mediators or moderators of alcoholism risk among subjects with a low LR.
Cigarette Smoking Exacerbates Chronic Alcohol‐Induced Brain Damage: A Preliminary Metabolite Imaging Study
Authors: Durazzo Timothy C. , Gazdzinski Stefan , Banys Peter , Meyerhoff Dieter J.
Published: December 2004

Background: Cigarette smoking is common among alcohol‐dependent individuals. Nevertheless, previous research has typically not accounted for the potential independent or compounding effects of cigarette smoking on alcohol‐induced brain injury and neurocognition.

Methods: Twenty‐four 1‐week‐abstinent recovering alcoholics (RAs; 14 smokers and 10 nonsmokers) in treatment and 26 light‐drinking controls (7 smokers and 19 nonsmokers) were compared on measures of common brain metabolites in gray matter and white matter of the major lobes, basal ganglia, midbrain, and cerebellar vermis, obtained via multislice short–echo time proton magnetic resonance spectroscopic imaging. Smoking and nonsmoking RAs were also contrasted on measures of neurocognitive functioning, as well as laboratory markers of drinking severity and nutritional status.

Results: Chronic alcohol dependence, independent of smoking, was associated with lower concentrations of frontal N‐acetylaspartate (NAA) and frontal choline‐containing compounds, as well as lower parietal and thalamic choline. Smoking RAs had lower NAA concentrations in frontal white matter and midbrain and lower midbrain choline than nonsmoking RAs. A four‐group analysis of covariance also demonstrated that chronic cigarette smoking was associated with lower midbrain NAA and choline and with lower vermian choline. In smoking RAs, heavier drinking was associated with heavier smoking, which correlated with numerous subcortical metabolite abnormalities. The 1‐week‐abstinent smoking and nonsmoking RAs did not differ significantly on a brief neurocognitive battery. In smoking RAs, lower cerebellar vermis NAA was associated with poorer visuomotor scanning speed and incidental learning, and in nonsmoking RAs lower vermis NAA was related to poorer visuospatial learning and memory.

Conclusions: These human in vivo proton magnetic resonance spectroscopic imaging findings indicate that chronic cigarette smoking exacerbates chronic alcohol‐induced neuronal injury and cell membrane damage in the frontal lobes of RAs and has independent adverse effects on neuronal viability and cell membranes in the midbrain and on cell membranes of the cerebellar vermis. Higher smoking levels are associated with metabolite concentrations in select subcortical structures. Greater consideration of the potential effects of comorbid cigarette smoking on alcohol‐induced brain damage and other diseases affecting the central nervous system is warranted.
In vitro and in vivo specificity of ubiquitination and degradation of STAT1 and STAT2 by the V proteins of the paramyxoviruses simian virus 5 and human parainfluenza virus type 2
Authors: Precious B. , Young D. F. , Andrejeva L. , Goodbourn S. , Randall R. E.
Published: December 2004

Previous work has documented that the V protein of simian virus 5 (SV5) targets STAT1 for proteasome-mediated degradation, whilst the V protein of human parainfluenza virus type 2 (hPIV2) targets STAT2. Here, it was shown that the processes of ubiquitination and degradation could be reconstructed in vitro by using programmed rabbit reticulocyte lysates. Using this system, the addition of bacterially expressed and purified SV5 V protein to programmed lysates was demonstrated to result in the polyubiquitination and degradation of in vitro-translated STAT1, but only if human STAT2 was also present. Surprisingly, in the same assay, purified hPIV2 V protein induced the polyubiquitination of both STAT1 and STAT2. In the light of these in vitro results, the specificity of degradation of STAT1 and STAT2 by SV5 and hPIV2 in tissue-culture cells was re-examined. As previously reported, STAT1 could not be detected in human cells that expressed SV5 V protein constitutively, whilst STAT2 could not be detected in human cells that expressed hPIV2 V protein, although the levels of STAT1 may also have been reduced in some human cells infected with hPIV2. In contrast, STAT1 could not be detected, whereas STAT2 remained present, in a variety of animal cells, including canine (MDCK) cells, that expressed the V protein of either SV5 or hPIV2. Thus, the V protein of SV5 appears to be highly specific for STAT1 degradation, but the V protein of hPIV2 is more promiscuous.
Upregulation of functionally active vascular endothelial growth factor by human cytomegalovirus
Authors: Reinhardt Barbara , Schaarschmidt Peter , Bossert Andrea , Lüske Anke , Finkenzeller Günter , Mertens Thomas , Michel Detlef
Published: December 2004

Human cytomegalovirus (HCMV) infection is known to modulate host gene expression and has been linked to the pathogenesis of vasculopathies; however, relevant pathomechanisms are still unclear. It was shown that HCMV infection leads to upregulation of vascular endothelial growth factor (VEGF) expression in human foreskin fibroblasts and coronary artery smooth muscle cells (SMC). Activation of VEGF transcription by HCMV infection was confirmed by transient-expression experiments, which revealed that a short promoter fragment, pLuc135 (−85 to +50), is sufficient for activation. Site-directed mutagenesis of Sp1-recognition sites within this fragment abolished the upregulation of transcription. Functional VEGF protein is released into the culture supernatant of infected SMC. Incubation of endothelial cells with supernatants from HCMV-infected SMC cultures induced upregulation of VEGF receptor-2 expression on endothelial cells, as well as a significant upregulation of DNA synthesis, implicating cell proliferation. The mean incline of DNA synthesis at 48 and 72 h post-infection was 148 and 197 %, respectively. Addition of neutralizing antibodies against VEGF completely abolished this effect. Supernatants from SMC cultures incubated with UV-inactivated virus induced a comparable effect. This virus-induced paracrine effect may represent a molecular mechanism for HCMV-induced pathogenesis, such as inflammatory vasculopathies, by inducing a proatherogenic phenotype in SMC.
Influence of residue 44 on the activity of the M2 proton channel of influenza A virus
Authors: Betakova Tatiana , Ciampor Fedor , Hay Alan J.
Published: December 2004

The influenza A virus M2 proton channel plays a role in two stages of virus replication. The proteins of two closely related strains of the avian H7 subtype of influenza A virus, Rostock and Weybridge, were found to differ in their pH-modulating activities and activation characteristics. Of three amino acid differences at residues 27, 38 and 44 within the membrane-spanning domain, substitution at residue 44 was necessary and sufficient to account for differences in trans-Golgi pH-modulating activity, whereas changes in all three were required to switch the activation characteristics of the Weybridge M2 to those of the Rostock M2. These results not only separate the two phenomena genetically, but also indicate that the ‘unique’ activation characteristics of the Rostock M2 channel were selected specifically. In addition, they point to the importance of functional complementarity between the activation characteristics of the M2 channel and the pH of membrane fusion by haemagglutinin during virus entry.
A novel class of herpesvirus with bivalve hosts
Authors: Davison Andrew J. , Trus Benes L. , Cheng Naiqian , Steven Alasdair C. , Watson Moira S. , Cunningham Charles , Deuff Rose-Marie Le , Renault Tristan
Published: December 2004

Ostreid herpesvirus 1 (OsHV-1) is the only member of the Herpesviridae that has an invertebrate host and is associated with sporadic mortality in the Pacific oyster (Crassostrea gigas) and other bivalve species. Cryo-electron microscopy of purified capsids revealed the distinctive T=16 icosahedral structure characteristic of herpesviruses, although the preparations examined lacked pentons. The gross genome organization of OsHV-1 was similar to that of certain mammalian herpesviruses (including herpes simplex virus and human cytomegalovirus), consisting of two invertible unique regions (UL, 167·8 kbp; US, 3·4 kbp) each flanked by inverted repeats (TRL/IRL, 7·6 kbp; TRS/IRS, 9·8 kbp), with an additional unique sequence (X, 1·5 kbp) between IRL and IRS. Of the 124 unique genes predicted from the 207 439 bp genome sequence, 38 were members of 12 families of related genes and encoded products related to helicases, inhibitors of apoptosis, deoxyuridine triphosphatase and RING-finger proteins, in addition to membrane-associated proteins. Eight genes in three of the families appeared to be fragmented. Other genes that did not belong to the families were predicted to encode DNA polymerase, the two subunits of ribonucleotide reductase, a helicase, a primase, the ATPase subunit of terminase, a RecB-like protein, additional RING-like proteins, an ion channel and several other membrane-associated proteins. Sequence comparisons showed that OsHV-1 is at best tenuously related to the two classes of vertebrate herpesviruses (those associated with mammals, birds and reptiles, and those associated with bony fish and amphibians). OsHV-1 thus represents a third major class of the herpesviruses.
Part of the C-terminal tail of the envelope gp41 transmembrane glycoprotein of human immunodeficiency virus type 1 is exposed on the surface of infected cells and is involved in virus-mediated cell fusion
Authors: Cheung Linda , McLain Lesley , Hollier Mark J. , Reading Steven A. , Dimmock Nigel J.
Published: December 2004

The C-terminal tail of the gp41 transmembrane glycoprotein of the human immunodeficiency virus type 1 (HIV-1) virion is usually thought to be inside the virion, but it has been shown recently that part of the tail is exposed on the virion exterior. Here, using a panel of antibodies, it was demonstrated that the same part of the tail is exposed on the surface of HIV-1-infected C8166 lymphoblastoid cells and HeLa cells infected with a gp41-expressing vaccinia virus recombinant. Both types of infected cell failed to react with p17 matrix protein-specific IgGs until permeabilized with saponin, confirming the integrity of the plasma membrane. Cell-surface exposure of the gp41 tail was independently demonstrated by inhibition of HIV-1-mediated cell–cell fusion by one of the gp41 tail-specific antibodies. These data also implicate the exposed region of the gp41 C-terminal tail either directly or indirectly in the viral fusion process. Its surface exposure suggests that the gp41 C-terminal tail may be a candidate for immune intervention or chemotherapy of infection.
Mapping the RNA-binding domain on the Apple chlorotic leaf spot virus movement protein
Authors: Isogai Masamichi , Yoshikawa Nobuyuki
Published: December 2004

The RNA-binding properties of the cell-to-cell movement protein (MP) of Apple chlorotic leaf spot virus were analysed. MP was expressed in Escherichia coli and was used in UV-crosslinking analysis, using a digoxigenin–UTP-labelled RNA probe and gel-retardation analysis. The analyses demonstrated that MP bound cooperatively to single-stranded RNA (ssRNA). When analysed for NaCl dependence of the RNA-binding activity, the majority of the MP could bind ssRNA even in binding buffer with 1 M NaCl. Furthermore, competition binding experiments showed that the MP bound preferentially to ssRNA and single-stranded DNA without sequence specificity. MP deletion mutants were used to identify the RNA-binding domain by UV-crosslinking analysis. Amino acid residues 82–126 and 127–287 potentially contain two independently active, single-stranded nucleic acid-binding domains.
Herpes simplex virus type 1 glycoprotein H binds to αvβ3 integrins
Authors: Parry Christopher , Bell Susanne , Minson Tony , Browne Helena
Published: December 2004

Glycoprotein H (gH) homologues are found in all members of the herpes virus family, and gH is one of the virion envelope glycoproteins that is essential for virus entry. In this study, a recombinant soluble form of Herpes simplex virus type 1 (HSV-1) gH, in which the ectodomain is fused to the Fc-binding region of IgG, has been generated. This was expressed in mammalian cells together with gL and the resulting gHFc–gL heterodimer was purified using Protein A Sepharose. Low-affinity cell binding assays showed that gHFc–gL bound specifically to Vero cells and mutation of a potential integrin-binding motif, Arg-Gly-Asp (RGD), in gH abolished binding. CHO cells failed to bind in this assay. However, CHO cells expressing the human αvβ3 integrin bound efficiently to gHFc–gL, suggesting that HSV-1 gH can bind to cells using αvβ3 integrins and that this binding is mediated by the RGD motif in the gH ectodomain.
Maternal serum and umbilical cord tumor marker levels at term pregnancy
Authors: Kiran Gurkan , Kiran Hakan , Guler Fatma Inanc , Ekerbicer Hasan Cetin , Kilinc Metin
Published: December 2004

Background.  The aim of the study was to compare the levels in fetal and maternal compartments of cancer antigen (CA) 125, CA 15‐3, carbohydrate antigen (CA) 19‐9, and carcinoembryonic antigen (CEA) and to determine the effects of fetal sex, parity, and fetal weight on umbilical cord (UC) and maternal serum (MS) levels of these markers.

Methods.  MS and UC levels of these markers were determined in blood samples taken simultaneously during cesarean delivery for 53 cases. All statistical analyses were performed using nonparametric tests (Wilcoxon's signed rank test, Mann–Whitney U‐test, Kruskal–Wallis anova). Correlations were evaluated with Spearman's rank correlation coefficients.

Results.  All marker levels of MS were significantly different to those of UC. There was no association between MS and UC levels of four markers and fetal sex. No significant difference could be demonstrated between fetal weight and marker levels in MS and UC. No significant difference could be demonstrated between parity and marker levels except CEA in MS that was elevated in multigravida group.

Conclusions.  Our results support that all markers except CA 15‐3 have oncofetal origin. We concluded that further studies are required to reveal the effects of fetal sex on MS CA 19‐9 and effects of parity on MS CEA levels.
Episiotomy and perineal tears presumed to be imminent: the influence on the urethral pressure profile, analmanometric and other pelvic floor findings – follow‐up study of a randomized controlled trial
Authors: Dannecker Christian , Hillemanns Peter , Strauss Alexander , Hasbargen Uwe , Hepp Hermann , Anthuber Christoph
Published: December 2004

Background.  The influence of the restrictive use of episiotomy at perineal tears judged to be imminent on the urethral pressure profile, analmanometric, and other pelvic floor findings is unknown.

Methods.  Follow‐up study of a randomized controlled trial with two perineal management policies includes the use of episiotomy: (a) only for fetal indications and (b) in addition at a tear presumed to be imminent. Participants were 146 primiparous women with an uncomplicated singleton pregnancy >34 weeks of gestation. For the intention‐to‐treat analysis, 68 women after vaginal delivery were included who delivered a live full‐term baby between January 1999 and September 2000.

Outcome measures.  Maximum urethral closure pressure (MUCP, cmH2O), functional urethral length (mm), maximum anal pressure (MAP, mmHg), functional anal sphincter length (ASL, mmHg) at rest and during contraction, and pelvic floor muscle strength (5‐grade Oxford score) are the outcome measures. The rate of dyspareunia, urinary incontinence, and anorectal incontinence was documented.

Results.  At a mean follow up of 7.3 months, there were no statistically significant differences between the two groups (a versus b): mean MUCP at rest (98 versus 101 cmH2O), during contraction (95 versus 103 cmH2O), mean MAP at rest (113 versus 121 mmHg), during contraction (143 versus 166 mmHg), mean ASL at rest (50 versus 50 mmHg), during contraction (42 versus 45 mmHg), mean pelvic floor muscle strength (2.2 versus 2.6), no pain during sexual intercourse (79 versus 67%), prevalence of urinary incontinence (48 versus 27%), and anorectal incontinence (19 versus 24%).

Conclusions.  Episiotomy at a perineal tear presumed to be imminent does not have any advantage with regard to pelvic floor function and should be avoided.
Impact of vaginal surgery on sexuality and quality of life in women with urinary incontinence or genital descensus
Authors: Helström Lotti , Nilsson Bo
Published: December 2004

Aim.  To study the effect of vaginal surgery for urinary incontinence and genital descensus on sexual function and quality of life.

Methods.  The day before surgery, 118 women, of whom 41 were admitted for urinary incontinence and 77 for genital descensus, accepted to complete a questionnaire containing questions of uterovaginal symptoms, quality of life, and sexuality. One year later, 101 women, of them 88 were sexually active, accepted to complete the same questionnaire by mail.

Results.  The women reported improvement in two different scales for quality of life, and there was no difference between surgery for genital descensus and that for urinary stress incontinence. The total score for sexual variables was deteriorated, and the mean frequency of sexual intercourse was reduced. Among women with genital descensus, 14% experienced more urinary incontinence and 13% more dyspareunia after the operation.

Conclusion.  Although pelvic floor disorders are known to impair sexual function, there was no improvement in sexuality after surgery for urinary incontinence or genital descensus. On the contrary, it seems that sexual function might deteriorate and dyspareunia get worse after vaginal surgery. The explanation for this might be vulnerability to disturbance of vaginal nerve and blood supply of the vaginal wall resulting in impaired sexual arousal and lubrication.
Views of midwives and gynecologists on legal abortion – a population‐based study
Authors: Hammarstedt Meta , Jacobsson Lars , Wulff Marianne , Lalos Ann
Published: December 2004

Background.  Little is known about staffs' attitudes and experiences of legal abortion. The aim of this study was to gain knowledge about the views of Swedish midwives and gynecologists on legal abortion. Another aim was to investigate differences between professions and possible impacting factors on these views.

Methods.  A questionnaire was sent to a random sample of 258 midwives and 269 gynecologists. The response rate was 84%.

Results.  The vast majority of all respondents supported the legislation on induced abortion. A great majority also believed that the woman alone should make the decision, and that abortion was not used as a form of contraception. Generally, there were smaller differences among views of female and male gynecologists than among views of female gynecologists and female midwives. For example, female midwives disagreed more than female gynecologists with the statement: ‘Legal abortion should be permitted even if the woman has felt fetal movements’. The most impacting factors on views were the extent to which the staffs had been working with legal abortion, especially during the last year, and type of profession. Views were, however, not influenced by private experiences of legal abortion.

Conclusions.  The present study highlights that midwives and gynecologists overwhelmingly agree that legal abortion should be allowed. The more experience of working with legal abortion, especially current experience, the less restrictive gynecologists and midwives are in their views. Compared with previous studies, staffs have become more liberal in their attitudes toward abortion and the relevant legislation.
Low‐impact exercise during pregnancy – a study of safety
Authors: Larsson Linnea , Lindqvist Pelle G.
Published: December 2004

Background.  Exercise is an important part of many women's lives. Women are often advised to refrain from physical exercise during pregnancy. The reason given is mainly safety, i.e. fear of maternal hyperthermia, which is known to be related to neural tube defects. However, exercise during pregnancy has not been shown to be related to hyperthermia.

Objective.  To study temperature and oxygen saturation responses to low‐impact exercise in healthy pregnant women.

Methods.  Forty pregnant women and 11 controls participating in low‐impact aerobic exercise were monitored before exercise, at maximum‐exercise level, and after exercise with regard to core temperature, heart rate, and oxygen saturation level.

Results.  The core temperature among the pregnant women did not increase significantly at maximum exercise or after exercise (36.5 versus 36.7 or 36.5 °C, P = 0.1, P = 0.5). None of the pregnant women were even close to approaching a dangerous body temperature at an intensity level of 69% of their maximum heart rate. As compared with pre‐exercise values, oxygen saturation among pregnant women was significantly reduced at both maximum‐exercise and postexercise measurements, but no measurement was below 95% in oxygen saturation.

Conclusion.  Low‐impact aerobics at about 70% of one's maximum heart rate appears to be safe in terms of risk of maternal hyperthermia.
Factors affecting the post‐release survival of cultured juvenile Pseudopleuronectes americanus
Authors: Fairchild E. A. , Howell W. H.
Published: December 2004

Laboratory experiments were performed with cultured and wild juvenile winter flounder Pseudopleuronectes americanus to evaluate differences in behaviour and adaptation affecting post‐release vulnerability to predation. Studies revealed that the cryptic abilities of cultured winter flounder increased over time. Sediment‐naïve, cultured fish required a minimum of 2 days to improve their burying skills and at least 90 days for colour adaptation to match the sediment. Cultured winter flounder selected sediments consisting of small grains and colours matching their own pigment. Cultured winter flounder, regardless of their colour, were significantly more vulnerable to predation by birds. Additionally, cultured fish reacted differently than wild winter flounder when exposed to cues from a potential predator.
Embryo survival and smolt to adult survival in second‐generation outbred coho salmon
Authors: Smoker W. W. , Wang I. A. , Gharrett A. J. , Hard J. J.
Published: December 2004

Outbreeding depression was not detectable in observations of embryonic survival and of survival of smolts to adulthood relative to controls in coho salmon Oncorhynchus kisutch experimentally outbred over two generations by crossing fish from three widely separated populations. Survival in outbred coho salmon was not detectably less than that in second‐generation hybrid controls or second‐generation parental controls. Variation of embryonic survival was affected by the maternal source population and by individual females but not by the paternal source population or by individual males. Survival of smolts to adulthood at sea was greater in one second‐generation control group than in two others, but survival in second‐generation outbred groups was no less than in parental controls or hybrid controls.
Escapees of potentially invasive fishes from an ornamental aquaculture facility: the case of topmouth gudgeon Pseudorasbora parva
Authors: Beyer K.
Published: December 2004

Accidental escapees from aquacultural facilities are an ongoing problem facing scientists, conservationists, policy makers and naturalists throughout the world. The topmouth gudgeon Pseudorasbora parva, a small cyprinid native to Southeast Asia, was introduced to Romanian waters in 1960 via the aquaculture trade and has since spread throughout Europe. It first appeared in England in an ornamental fish farm near Romsey in Hampshire. The aim of the present study was to quantify the dispersal of this potentially highly invasive species from an ornamental fish farm into the wild. In order to measure the dispersal of escapees, intensive electrofishing surveys were carried out between June and September 2003 in the catchment downstream of the fish farm. The distribution of topmouth gudgeon in the catchment was found to be limited and patchy. The presence of small individuals suggests that the species has successfully established itself in the wild, but this remains to be confirmed. The results were examined in light of invasion theory principles of biological resistance and ecological fitness.
Influence of rearing method on ide Leuciscus idus L. juvenile survival under pike and pikeperch predation
Authors: Ciesla M. , Kaczkowski Z.
Published: December 2004

The influence of rearing methods on ide Leuciscus idus L. juvenile survival under pike and pikeperch predation was investigated. Survival of two groups of ide was compared: group (1) consisted of juveniles reared in tanks under fully controlled conditions, while group (2) consisted of pond‐reared juveniles. Both groups were obtained from the same parents, separated at the larval stage in early spring and cultured in the different environments until late autumn. Juveniles from both groups were placed in tanks with pike or pikeperch, and their survival compared after one, three and six days of exposure to the predators.
Laboratory simulation of the effects of environmental salinity on wild‐caught juveniles of European sea bass Dicentrarchus labrax and gilthead seabream Sparus aurata
Authors: Conides A. J. , Glamuzina B. , Papaconstantinou C.
Published: December 2004

Gilthead seabream Sparus aurata and European sea bass Dicentrarchus labrax, are two important species in Mediterranean aquaculture. In the wild, their juveniles occur in brackish areas such as lagoons and river deltas. Even though the juveniles seem to favour brackish environments, low salinity incurs an energy cost for osmoregulation. This paper presents the results of a series of laboratory experiments exploring the effects of salinity on growth, feeding, food conversion, survival and maintenance energy requirements of wild‐caught juveniles. The fish were kept in the laboratory, divided in groups of 20 in small tanks of 50 l each, and supplied with biologically filtered seawater of four salinity levels (8, 18, 28‰ and natural seawater) and fixed temperature (20 ± 1·4° C). The fish were fed pelleted feed throughout the experiment. Both species showed great similarity in their responses to lower salinities. Satiation time for both species increased with decreasing salinity, while maintenance requirements (required daily ration and energy) increased as with increasing salinity. Growth and feed conversion is highest for salinities around 28‰ and lower for salinities above and below. Both species share common physiological features, and intermediate salinities are optimal for their performance in nature and in captivity.
Testing predictions of the critical period for survival concept using experiments with stocked Atlantic salmon
Authors: Nislow K. H. , Einum S. , Folt C. L.
Published: December 2004

Two separate field experiments were performed in the U.S.A. and Norway with stocked Atlantic salmonSalmo salar. In the Norwegian experiment, the offspring of early‐spawning fish which had larger eggs and emerged a few days before offspring of later spawning fish had consistently higher survival rates. In the U.S.A. experiment, stream sections with higher proportions of favourable foraging locations during the critical period (the transition from dependence on maternally‐derived yolk reserves to independent feeding) had lower loss rates of fish stocked as unfed fry. These results provide support for the critical period concept (CPC) in Atlantic salmon, underscores the utility of a manipulative approach to achieve further advances in knowledge of Atlantic salmon ecology and provide additional guidance to management and restoration. A mechanistic, conceptual model for density dependence is presented to identify important knowledge gaps that remain to further evaluate the importance of the CPC for Atlantic salmon population regulation.
Swimming activity of seabass: comparing patterns obtained in natural environment and in re‐circulating tanks under high density
Authors: Bégout Anras M.‐L. , Lagardère J. P. , Covès D.
Published: December 2004

Seabass (Dicentrarchus labrax) swimming activity was compared between natural environments and aquaculture facilities. Behaviour under natural conditions was assessed in a saltmarsh pond (250 m2, 18 × 14 × 0·8 m) using acoustic telemetry. From several surveys, we documented the diel activity rhythm and demonstrated group effects on swimming patterns and amplitudes by comparing activity of solitary fish with that of a fish living in a group of 60. Consequences of weather variability were also analysed and revealed a high sensitivity of fish to atmospheric conditions for both swimming and demand‐feeding behaviour. Behaviour in fish tanks was also studied using acoustic telemetry, as part of the EUREKA EU1 960 ‘Aqua‐Maki 2’ project investigating aspects of fish culture in re‐circulating tanks under high density. A re‐circulating hexagonal tank (5·4 × 5·4 m, 1·8 m depth, 48 m3) was equipped with positioning and demand‐feeding systems, oxygen and temperature probes. Initial density was 50 kg m3 in March and rose to 90 kg m3 at the end of the experiment in May. During this period, the movements of nine fish were continuously recorded for 24 h each, reaching a total of six 24 h episode at eight days interval. Swimming activity was analysed in terms of activity rhythms and space occupation specially around feeding events. The two data set and main results will be presented and compared to assess seabass behavioural plasticity and sensitivity to husbandry conditions.
Comparison of maturation timing, egg size and fecundity between hatchery lines of chinook salmon and their wild donor stocks
Authors: Joyce J. E. , Wertheimer A. C. , Gray A. , Thrower F.
Published: December 2004

Increasing concern has been expressed about the genetic effects of cultured salmonid fishes on natural populations. Avoidance of extreme negative outcomes was one reason for the establishment of a genetic management policy for the State of Alaska. However, domestication within the hatchery may still cause divergence from the wild donor population. This divergence could potentially lead to adverse impacts on wild stocks through straying and introgression. This study examines potential domestication in two Alaskan chinook salmon stocks. The Little Port Walter (LPW) Hatchery Chickamin River stock resulted from a small collection of wild broodstock in 1976. The LPW Unuk stock was founded with a larger number of individuals in 1976 and has had subsequent infusion of wild gametes. These lines have been maintained at LPW through ocean ranching of tagged smolts. Comparisons are made between the hatchery lines, progeny of wild chinook collected from the Chickamin and Unuk Rivers, and hybrids between the hatchery and wild groups. Mature ocean‐ranched female chinook salmon returning to the facility were periodically graded for ripeness and spawned. Body size and meristic measurements were collected from these mature spawners. Maturation timing, fecundity, and individual egg size of these fourth generation hatchery fish are compared with that of offspring of wild fish from the same donor stock. Stock of origin is confirmed for all spawners and offspring using microsatellite DNA analysis.