bluuebunny/crossref_metadata_2025_split huggingface dataset:
Innate Immune Responses and Permissiveness to Ranavirus Infection of Peritoneal Leukocytes in the FrogXenopus laevis
Authors: Morales Heidi D. , Abramowitz Lara , Gertz Jacqueline , Sowa Jessica , Vogel Ashley , Robert Jacques 
Published: March 2010

ABSTRACTRanaviruses such as frog virus 3 ([FV3] familyIridoviridae) are increasingly prevalent pathogens that infect reptiles, amphibians, and fish worldwide. Whereas studies in the frogXenopus laevishave revealed the critical involvement of CD8 T-cell and antibody responses in host resistance to FV3, little is known about the role played by innate immunity to infection with this virus. We have investigated the occurrence, composition, activation status, and permissiveness to infection of peritoneal leukocytes (PLs) inXenopusadults during FV3 infection by microscopy, flow cytometry, and reverse transcription-PCR. The total number of PLs and the relative fraction of activated mononucleated macrophage-like cells significantly increase as early as 1 day postinfection (dpi), followed by NK cells at 3 dpi, before the peak of the T-cell response at 6 dpi. FV3 infection also induces a rapid upregulation of proinflammatory genes including arginase 1, interleukin-1β, and tumor necrosis factor alpha. Although PLs are susceptible to FV3 infection, as evidenced by apoptotic cells, active FV3 transcription, and the detection of viral particles by electron microscopy, the infection is weaker (fewer infectious particles), more transitory, and involves a smaller fraction (less than 1%) of PLs than the kidney, the main site of infection. However, viral DNA remains detectable in PLs for at least 3 weeks postinfection, past the point of viral clearance observed in the kidneys. This suggests that although PLs are actively involved in anti-FV3 immune responses, some of these cells can be permissive and harbor quiescent, asymptomatic FV3.
Binding Site on the Transferrin Receptor for the Parvovirus Capsid and Effects of Altered Affinity on Cell Uptake and Infection
Authors: Goodman Laura B. , Lyi Sangbom M. , Johnson Natalie C. , Cifuente Javier O. , Hafenstein Susan L. , Parrish Colin R. 
Published: March 2010

ABSTRACTCanine parvovirus (CPV) and its relative feline panleukopenia virus (FPV) bind the transferrin receptor type 1 (TfR) to infect their host cells but show differences in the interactions with the feline and canine TfRs that determine viral host range and tissue tropism. We changed apical and protease-like domain residues by introducing point mutations and adding or removing glycosylation signals, and we then examined the interactions of those mutant TfRs with the capsids. Most substitutions had little effect on virus binding and uptake. However, mutations of several sites in the apical domain of the receptor either prevented binding to the capsids or reduced the affinity of receptor binding to various degrees. Glycans within the virus binding face of the apical domain also controlled capsid binding. CPV, but not the related feline parvovirus, could use receptors containing a canine TfR-specific glycosylation to mediate efficient infection, while addition of other N-linked glycosylation sites into the virus binding face of the feline apical domain reduced or eliminated both binding and infection. Replacement of critical feline TfR residue 221 with every amino acid had effects on binding and infection which were significantly associated with the biochemical properties of the residue replaced. Receptors with reduced affinities mostly showed proportional changes in their ability to mediate infection. Testing feline TfR variants for their binding and uptake patterns in cells showed that low-affinity versions bound fewer capsids and also differed in attachment to the cell surface and filopodia, but transport to the perinuclear endosome was similar.
The First Complete Papillomavirus Genome Characterized from a Marsupial Host: a Novel Isolate from
Bettongia penicillata
Authors: Bennett Mark D. , Reiss Andrea , Stevens Hans , Heylen Elisabeth , Van Ranst Marc , Wayne Adrian , Slaven Michael , Mills Jennifer N. , Warren Kristin S. , O'Hara Amanda J. , Nicholls Philip K. 
Published: March 2010

ABSTRACT

The first fully sequenced papillomavirus (PV) of marsupials, tentatively named
Bettongia penicillata
papillomavirus type 1 (BpPV1), was detected in papillomas from a woylie (
Bettongia penicillata ogilbyi
). The circular, double-stranded DNA genome contains 7,737 bp and encodes 7 open reading frames (ORFs),
E6
,
E7
,
E1
,
E2
,
E4
,
L2
, and
L1
, in typical PV conformation. BpPV1 is a close-to-root PV with
L1
and
L2
ORFs most similar to European hedgehog PV and bandicoot papillomatosis carcinomatosis virus types 1 and 2 (BPCV1 and -2). It appears that the BPCVs arose by recombination between an ancient PV and an ancient polyomavirus more than 10 million years ago.
Prevalence ofTrichomonas vaginalisinfection in women attending a major gynaecological hospital in Greece: a cross-sectional study
Authors: Piperaki Evangelia-Theophano , Theodora Marianna , Mendris Michael , Barbitsa Louisa , Pitiriga Vassiliki , Antsaklis Aris , Tsakris Athanassios 
Published: March 2010

BackgroundThe prevalence ofTrichomonas vaginalisis not accurately estimated, since it is not a reportable disease.AimsTo assess the prevalence ofT vaginalisinfection in women attending a Greek gynaecological hospital and to evaluate four diagnostic methods forT vaginalisinfection.Methods255 symptomatic and 247 asymptomatic women were included in the study during 2006–07; 372 were Greek and 130 were immigrants.T vaginaliswas detected in vaginal samples, using wet mount, culture in modified Diamond's medium, antigen detection and two PCR assays, targeting different regions ofT vaginalisgenome. Specimens were considered positive forT vaginalis, when tested positive either by culture or by both PCRs.Results23 women (4.6%) were positive forT vaginalis. Seven of the 23 positive samples (30.4%) were only PCR-positive. Infection was more prevalent in symptomatic women (6.7%) than in asymptomatic ones (2.4%).T vaginaliswas more frequently detected in immigrants (7.9%) than in Greek women (3.3%).Gardnerella vaginalisinfection was significantly more frequent in women infected withT vaginalis. PCR was the most sensitive method (100%), followed by culture (69.6%), wet mount (69.6%) and latex agglutination (54.6%). Agreement between PCR and culture as well as wet mount examination was very good (κ=0.79).ConclusionsThe study shows a relatively low percentage of trichomoniasis in the female population living in Athens. The infection was more prevalent among immigrants, and a proportion of the infected women was asymptomatic. The tested methods had good agreement and PCR was found to improve the diagnostic yield considerably.
Human herpesvirus type 8 in patients with cirrhosis independent of thrombocytopenia
Authors: Chou A-L , Huang W-W , Lin M-N , Su C-C 
Published: March 2010

BackgroundHigh seroprevalence of human herpesvirus type 8 (HHV-8) in patients with cirrhosis has been reported to be associated with thrombocytopenia. Severe cirrhosis is always complicated with ascites. HHV-8 DNA levels in effusion from patients with primary effusion lymphoma has been reported to be significantly greater than in blood. The status of HHV-8 antibody and DNA in cirrhotic ascites is unclear.AimsTo assess the status of HHV-8 antibody and DNA in cirrhotic ascites compared to that in cirrhotic plasma.MethodsPlasma and ascites samples were collected from 85 patients with cirrhosis. HHV-8 antibody and DNA were detected by immunofluorescence assay and PCR, respectively.ResultsMale patients seropositive for HHV-8 antibody were significantly younger than seropositive female patients (p=0.0039). The seropositive rate in patients with cirrhosis was not associated with thrombocytopenia (p=0.6860). Both positive rate and titres of antibody in plasma were much greater than in ascites (p<0.0001). More male or Child–Pugh class C than female or class B seropositive patients were positive for ascites. No hepatitis C virus-related ascites were positive for antibody. Neither plasma nor ascites samples from any subject were positive for HHV-8 DNA.ConclusionsIn patients with cirrhosis, the seropositive rate for HHV-8 antibody is independent of thrombocytopenia. The positive rate for HHV-8 antibody in cirrhotic ascites seems to be associated with sex, disease severity and disease aetiology.
Glomus indicum, a new arbuscular mycorrhizal fungus
Authors: Błaszkowski Janusz , Wubet Tesfaye , Harikumar Variampally Sankar , Ryszka Przemysław , Buscot François 
Published: March 2010

A new arbuscular mycorrhizal fungal species of the genus Glomus , Glomus indicum (Glomeromycota), forming small, hyaline spores in hypogeous aggregates is described and illustrated. The spores are globose to subglobose, (17–)32(–52) µm in diameter, rarely egg-shaped, oblong to irregular, 17–38 µm × 19–43 µm. The single spore wall of G. indicum consists of two hyaline layers: a mucilaginous, short-lived, thin outer layer staining pinkish to pink in Melzer's reagent and a laminate, smooth, permanent, thicker inner layer. Glomus indicum was found in the rhizosphere of Euphorbia heterophylla L. naturally growing in coastal sands of Alappuzha in Kerala State of South India and Lactuca sativa L. cultivated in Asmara, Eritrea, North East Africa. In single-species cultures with Plantago lanceolata L. as the host plant, G. indicum formed vesicular-arbuscular mycorrhiza. Molecular analysis of the phylogenetic position of G. indicum based on both SSU and ITS rDNA sequences showed the fungus to be a new species with its own cluster. Besides the sites where the spores were observed, sequence types belonging to the G. indicum cluster were documented from environmental samples mainly in the USA, Estonia, and Australia, suggesting the wide occurrence of the species. A key to all known species of the Glomeromycota producing hyaline to light-coloured glomoid spores is provided.
Turnover and fractionation of carbon and nitrogen stable isotopes in tissues of a migratory coastal predator, summer flounder (Paralichthys dentatus)
Authors: Buchheister Andre , Latour Robert J. 
Published: March 2010

Migratory and mobile fishes such as summer flounder ( Paralichthys dentatus ) often utilize dietary resources with stable isotope signatures that vary over time and space, potentially confounding diet analyses if tissues with slow turnover are sampled before reaching isotopic equilibrium. A laboratory diet-shift study was conducted using juvenile and young adult summer flounder to (i) determine isotopic turnover rates and fractionations of δ13C and δ15N in liver, whole blood, and white muscle and (ii) estimate the relative importance of growth and metabolic processes on isotopic turnover. Isotopic turnover rates were consistently ranked liver > blood > muscle owing to increased metabolic activities of liver and blood. Carbon and nitrogen half-lives ranged from 10 to 20 days (liver), 22 to 44 days (blood), and 49 to 107 days (muscle), indicating that liver and blood are more useful than muscle as shorter-term dietary indicators for summer flounder and other migratory fishes. Growth-based fractionation estimates of wild flounder tissues ranged from 0.71‰ to 3.27‰ for carbon and from 2.28‰ to 2.80‰ for nitrogen and included the first explicit estimates for isotopic fractionation in fish blood. A generalized model for predicting the time scale of isotopic turnover from growth-based turnover parameters was also developed to help evaluate isotopic equilibrium assumptions of fishes in the field.
Thermal reaction norms in sperm performance of Atlantic cod (Gadus morhua)
Authors: Purchase Craig F. , Butts Ian A.E. , Alonso-Fernández Alexandre , Trippel Edward A. 
Published: March 2010

Phenotypic plasticity occurs when a genotype produces variable phenotypes under different environments; the shapes of such responses are known as norms of reaction. The genetic scale at which reaction norms can be determined is restricted by the experimental unit that can be exposed to variable environments. This has limited their description beyond the family level in higher organisms, thus hindering our understanding of differences in plasticity at the scale of the individual. Using a three-year common-garden experiment, we quantify reaction norms in sperm performance of individual genotypes within different families of Atlantic cod ( Gadus morhua ). Cod sperm showed phenotypic plasticity in swimming performance across temperatures (3, 6, 11, and 21 °C), but the pattern of the response depended upon how long sperm had been swimming (30, 60, 120, or 180 s), i.e., plasticity in plasticity. Sperm generally swam fastest at intermediate temperatures when first assessed at 30 s after activation. However, a significant genotype × environment interaction was present, indicating inter-individual differences in phenotypic plasticity. To our knowledge, this is the first study to describe variable sperm performance across environmental conditions as a reaction norm. The results have potential theoretical, conservation, and aquaculture implications.
Mixed micelles of poly(styrene-b-3-(methacryloylamino)propyltrimethylammonium chloride-b-ethylene oxide) and anionic amphiphiles in aqueous solutions
Authors: Liu Jingjing , Yoneda Airi , Liu Dian , Yokoyama Yuuichi , Yusa Shin-ichi , Nakashima Kenichi 
Published: March 2010

The micelles of poly(styrene-b-3-(methacryloylamino)propyltrimethylammonium chloride-b-ethylene oxide) (PS-b-PMAPTAC-b-PEO) have been successfully prepared in aqueous solutions. The micelles have a PS core, cationic PMAPTAC shell, and PEO corona. Due to the short PS chain (degree of polymerization = 8), the formation of micelles is difficult at a low concentration, and the micelles are detected only at concentrations higher than 1 g L–1. The addition of anionic amphiphiles, such as sodium dodecyl sulfate (SDS) and poly(methacrylic acid) (PMAA), induces the formation of mixed micelles at a low concentration level of the polymer (~0.005 g L–1). This can be ascribed to insolubilization of the cationic PMAPTAC block due to charge neutralization by the anionic amphiphiles. The binding of SDS or PMAA to the PMAPTAC block is confirmed by zeta-potential measurements. The mixed micelles are characterized by dynamic light scattering (DLS), scanning electron microscopy (SEM), and fluorescence measurements. Based on DLS measurements, it is revealed that the hydrodynamic diameter of the mixed micelles falls in the range of 120–130 nm. SEM measurements provided clear pictures of mixed micelles with a spherical morphology. The kinetics of exchange of organic dyes between the micelle particles was investigated by fluorescence techniques. The result indicates that the exchange of the dyes between the micelle particles takes places within a time scale of seconds.
How switching the substituent of a pyrene derivative from a methyl to a butyl affects the fluorescence response of polystyrene randomly labeled with pyrene
Authors: Ingratta Mark , Mathew Manoj , Duhamel Jean 
Published: March 2010

A series of polystyrenes randomly labeled with 1-pyrenebutanol were prepared by copolymerizing styrene and 1-pyrenebutylacrylate yielding the CoBuE–PS series. Solutions of CoBuE–PS were prepared in nine organic solvents having viscosities ranging from 0.36 to 5.5 mPa·s and the fluorescence spectra and pyrene monomer and excimer fluorescence decays were acquired. Analysis of the fluorescence spectra yielded the IE/IM ratio, whereas analysis of the fluorescence decays with the fluorescence blob model (FBM) yielded the parameters N blobo , <kblob × Nblob> , and k blobo . These parameters were compared to those obtained with two other series of pyrene-labeled polystyrenes, which had been studied earlier, namely CoA–PS and CoE–PS where pyrene was attached to the polymer backbone via a methylamide and benzyl methylether linker, respectively. Although the parameters IE/IM, N blobo , <kblob × Nblob>, and k blobo took different values according to the specific nature of the linker connecting pyrene to the polystyrene backbone, they exhibited trends that were quite similar for all the pyrene-labeled polystyrene constructs. The excellent agreement between the parameters retrieved for the three different types of pyrene-labeled polystyrenes suggests that the FBM accounts satisfyingly for differences in the nature of the label used, while still retrieving information pertinent to the polymer of interest.
Biomaterials for neural-tissue engineering — Chitosan supports the survival, migration, and differentiation of adult-derived neural stem and progenitor cells
Authors: Scanga Vanessa I. , Goraltchouk Alex , Nussaiba Nasser , Shoichet Molly S. , Morshead Cindi M. 
Published: March 2010

Neural precursor cells (NPCs or stem and progenitor cells) are promising in transplantation strategies to treat an injury to the central nervous system, such as a spinal cord injury (SCI), because of their ability to differentiate into neurons and glia. Transplantation studies to date have met with limited success for a number of reasons, including poor cell survival. One way to encourage cell survival in injured tissue is to provide the cells with a scaffold to enhance their survival, their integration, and potentially their differentiation into appropriate cell types. Towards this end, four amine-functionalized hydrogels were screened in vitro for adult murine NPC viability, migration, and differentiation: chitosan, poly(oligoethylene oxide dimethacrylate-co-2-amino ethyl methacrylate), blends of poly(oligoethylene oxide dimethacrylate-co-2-amino ethyl methacrylate), and poly(vinyl alcohol), and poly(glycerol dimethacrylate-co-2-amino ethyl methacrylate). The greatest cell viability was found on chitosan at all times examined, Chitosan had the greatest surface amine content and the lowest equilibrium water content, which likely contributed to the greater NPC viability observed over three weeks in culture. Only chitosan supported survival of multipotent stem cells and the differentiation of the progenitors into neurons, astrocytes, and oligodendrocytes. Plating intact NPC colonies revealed greater cell migration on chitosan relative to the other hydrogels. Importantly, long term cultures on chitosan showed no significant difference in total cell counts over time, suggesting no net cell growth. Together, these findings reveal chitosan as a promising material for the delivery of adult NPC cell-based therapies.
A study of the intermolecular branch frequency dependence of tie-chain concentration in single-site linear low-density polyethylene blown films by a new FTIR method
Authors: Wang Mingtao , Li Nan , Choi Phillip , Zhang Yaolin 
Published: March 2010

The relative concentrations of tie chains (TCs) in six single-site linear low-density polyethylene blown films (LLDPE) were measured using a polarized Fourier transform infrared (FTIR) technique along with a newly developed sample preparation strategy. Before the FTIR measurements, the films were first subjected to a tensile strain of 20% using a homemade appliance and then annealed at a temperature of 60 °C over a time period of 24 h to relax all nonTCs in the amorphous phase. The relative TC concentrations were inferred from the FTIR measurement of the orientation order of the amorphous chains in the stretched films. It is believed that a greater concentration of TCs leads to a higher orientation order for the amorphous chains. The results showed that the quantity of TCs is essentially determined by the chains with the appropriate branch frequency (∼12 branches per 1000 backbone carbons based upon the films used in this work), especially those of the high molar mass chains as formation of TCs requires suitable ethylene sequence lengths between branches. The dart impact strength of the films appeared to be positively related to the relative concentration of TCs; films with greater concentrations showed higher dart impact strength. No clear correlations were observed between the relative concentration of TCs and the tear resistance of the films. However, the TC concentration seems to be related to the magnitude of the difference between the transverse direction and machine direction tear resistance.
The impact of Sirex noctilio in Pinus resinosa and Pinus sylvestris stands in New York and Ontario
Authors: Dodds Kevin J. , de Groot Peter , Orwig David A. 
Published: March 2010

Sirex noctilio Fabricius has a long history as an invasive insect species in pine plantations throughout the Southern Hemisphere and has been recently discovered in North America, where it is uncertain how this insect will behave in pine ecosystems. To assess the impact and attack behavior of S. noctilio, forest surveys and measurements from attacked and unattacked trees were taken in nine Pinus resinosa Ait. and Pinus sylvestris L. plantations in New York, USA, and Ontario, Canada. There was a trend of S. noctilio attacking suppressed trees with smaller live crowns and reduced growth. Some S. noctilio attacks were also found in dominant crown classes but at a lower rate than overtopped or intermediate classes. Sirex noctilio appeared to have more of an impact in P. sylvestris forests, as they attacked more stems (9%–18%) and higher basal area (1.6–5.5 m2/ha) than P. resinosa stands (3%–8% of stems and 0.4–2.4 m2/ha). Dead trees with signs of Siricidae and dead from other causes were also quantified, and in some P. resinosa stands, levels were greater in magnitude than S. noctilio losses. Data from this study suggest that silvicultural treatments should be a key component of integrated pest management plans for S. noctilio.
Landscape-scale parameterization of a tree-level forest growth model: a k-nearest neighbor imputation approach incorporating LiDAR data
Authors: Falkowski Michael J. , Hudak Andrew T. , Crookston Nicholas L. , Gessler Paul E. , Uebler Edward H. , Smith Alistair M.S. 
Published: March 2010

Sustainable forest management requires timely, detailed forest inventory data across large areas, which is difficult to obtain via traditional forest inventory techniques. This study evaluated k-nearest neighbor imputation models incorporating LiDAR data to predict tree-level inventory data (individual tree height, diameter at breast height, and species) across a 12 100 ha study area in northeastern Oregon, USA. The primary objective was to provide spatially explicit data to parameterize the Forest Vegetation Simulator, a tree-level forest growth model. The final imputation model utilized LiDAR-derived height measurements and topographic variables to spatially predict tree-level forest inventory data. When compared with an independent data set, the accuracy of forest inventory metrics was high; the root mean square difference of imputed basal area and stem volume estimates were 5 m2·ha–1 and 16 m3·ha–1, respectively. However, the error of imputed forest inventory metrics incorporating small trees (e.g., quadratic mean diameter, tree density) was considerably higher. Forest Vegetation Simulator growth projections based upon imputed forest inventory data follow trends similar to growth projections based upon independent inventory data. This study represents a significant improvement in our capabilities to predict detailed, tree-level forest inventory data across large areas, which could ultimately lead to more informed forest management practices and policies.