bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intracellular Processing, Glycosylation, and Cell Surface Expression of Human Metapneumovirus Attachment Glycoprotein
Authors: Liu Li , Bastien Nathalie , Li Yan 
Published: October 2007

ABSTRACT

The biosynthesis and posttranslational processing of human metapneumovirus attachment G glycoprotein were investigated. After pulse-labeling, the G protein accumulated as three species with molecular weights of 45,000, 50,000, and 53,000 (45K, 50K, and 53K, respectively).
N
-Glycosidase digestion indicated that these forms represent the unglycosylated precursor and N-glycosylated intermediate products, respectively. After an appropriate chase, these three naive forms were further processed to a mature 97K form. The presence of O-linked sugars in mature G protein was confirmed by
O
-glycanase digestion and lectin-binding assay using
Arachis hypogaea
(peanut agglutinin), an O-glycan-specific lectin. In addition, in the O-glycosylation-deficient cell line (CHO ldlD cell), the G protein could not be processed to the mature form unless the exogenous Gal and GalNAc were supplemented, which provided added evidence supporting the O-linked glycosylation of G protein. The maturation of G was completely blocked by monensin but was partially sensitive to brefeldin A (BFA), suggesting the O-linked glycosylation of G initiated in the trans-Golgi compartment and terminated in the trans-Golgi network. Enzymatic deglycosylation analysis confirmed that the BFA-G was a partial mature form containing N-linked oligosaccharides and various amounts of O-linked carbohydrate side chains. The expression of G protein at the cell surface could be detected by indirect immunofluorescence staining assay. Furthermore, cell surface immunoprecipitation displayed an efficient intracellular transport of G protein.
RNA Binding Domain of Jamestown Canyon Virus S Segment RNAs
Authors: Ogg Monica M. , Patterson Jean L. 
Published: October 2007

ABSTRACT

Jamestown Canyon virus (JCV) is a member of the
Bunyaviridae
family,
Orthobunyavirus
genus, California serogroup. Replication and, ultimately, assembly and packaging rely on the process of encapsidation. Therefore, the ability of viral RNAs (vRNAs) (genomic and antigenomic) to interact with the nucleocapsid protein (N protein) and the location of this binding domain on the RNAs are of interest. The questions to be addressed are the following. Where is the binding domain located on both the vRNA and cRNA strands, is this RNA bound when double or single stranded, and does this identified region have the ability to transform the binding potential of nonviral RNA? Full-length viral and complementary S segment RNA, as well as 3′ deletion mutants of both vRNA and cRNA, nonviral RNA, and hybrid viral/nonviral RNA, were analyzed for their ability to interact with bacterially expressed JCV N protein. RNA-nucleocapsid interactions were examined by UV cross-linking, filter binding assays, and the generation of hybrid RNA to help define the area responsible for RNA-protein binding. The assays identified the region responsible for binding to the nucleocapsid as being contained within the 5′ half of both the genomic and antigenomic RNAs. This region, if placed within nonviral RNA, is capable of altering the binding potential of nonviral RNA to levels seen with wild-type vRNAs.
Prion Strain- and Species-Dependent Effects of Antiprion Molecules in Primary Neuronal Cultures
Authors: Cronier Sabrina , Beringue Vincent , Bellon Anne , Peyrin Jean-Michel , Laude Hubert 
Published: October 2007

ABSTRACTTransmissible spongiform encephalopathies (TSE) arise as a consequence of infection of the central nervous system by prions and are incurable. To date, most antiprion compounds identified by in vitro screening failed to exhibit therapeutic activity in animals, thus calling for new assays that could more accurately predict their in vivo potency. Primary nerve cell cultures are routinely used to assess neurotoxicity of chemical compounds. Here, we report that prion strains from different species can propagate in primary neuronal cultures derived from transgenic mouse lines overexpressing ovine, murine, hamster, or human prion protein. Using this newly developed cell system, the activity of three generic compounds known to cure prion-infected cell lines was evaluated. We show that the antiprion activity observed in neuronal cultures is species or strain dependent and recapitulates to some extent the activity reported in vivo in rodent models. Therefore, infected primary neuronal cultures may be a relevant system in which to investigate the efficacy and mode of action of antiprion drugs, including toward human transmissible spongiform encephalopathy agents.
Identification of Regions and Residues in Feline Junctional Adhesion Molecule Required for Feline Calicivirus Binding and Infection
Authors: Ossiboff Robert J. , Parker John S. L. 
Published: October 2007

ABSTRACTThe feline junctional adhesion molecule A (fJAM-A) is a functional receptor for feline calicivirus (FCV). fJAM-A is a member of the immunoglobulin superfamily (IgSF) and consists of two Ig-like extracellular domains (D1 and D2), a membrane-spanning domain, and a short cytoplasmic tail. To identify regions of fJAM-A that interact with FCV, we purified recombinant fJAM-A ectodomain and D1 and D2 domains. We found that preincubation of FCV with the ectodomain or D1 was sufficient to inhibit FCV infection in plaque reduction assays. In enzyme-linked immunosorbent assays, FCV binding to fJAM-A ectodomain was concentration dependent and saturable; however, FCV bound D1 alone weakly and was unable to bind D2. To characterize FCV binding to surface-expressed fJAM-A, we transfected truncated and chimeric forms of fJAM-A into a nonpermissive cell line and assayed binding by flow cytometry. Only D1 was necessary for FCV binding to cells; all other domains could be replaced. Using a structure-guided mutational approach, we identified three mutants of fJAM-A within D1 (D42N, K43N, and S97A) that exhibited significantly decreased capacities to bind FCV. In contrast to our finding that D1 mediated FCV binding, we found that all domains of fJAM-A were necessary to confer susceptibility to FCV infection. Furthermore, surface expression of fJAM-A was not sufficient to permit FCV infection by all of the isolates we investigated. This indicates that (i) other cellular factors are required to permit productive FCV infection and (ii) individual FCV isolates differ in the factors they require.
Antiviral Antibodies Are Necessary To Prevent Cytotoxic T-Lymphocyte Escape in Mice Infected with a Coronavirus
Authors: Butler Noah S. , Dandekar Ajai A. , Perlman Stanley 
Published: October 2007

ABSTRACTMutation within virus-derived CD8 T-cell epitopes can effectively abrogate cytotoxic T-lymphocyte (CTL) recognition and impede virus clearance in infected hosts. These so-called “CTL escape variant viruses” are commonly selected during persistent infections and are associated with rapid disease progression and increased disease severity. Herein, we tested whether antiviral antibody-mediated suppression of virus replication and subsequent virus clearance were necessary for preventing CTL escape in coronavirus-infected mice. We found that compared to wild-type mice, B-cell-deficient mice did not efficiently clear infectious virus, uniformly developed clinical disease, and harbored CTL escape variant viruses. These data directly demonstrate a critical role for antiviral antibody in protecting from the selective outgrowth of CTL escape variant viruses.
Ubiquitin Depletion and Dominant-Negative VPS4 Inhibit Rhabdovirus Budding without Affecting Alphavirus Budding
Authors: Taylor Gwen M. , Hanson Phyllis I. , Kielian Margaret 
Published: October 2007

ABSTRACT
The budding reactions of a number of enveloped viruses use the cellular machinery involved in the formation of the luminal vesicles of endosomal multivesicular bodies (MVB). Budding of these viruses is dependent on the presence of specific late-domain motifs in membrane-associated viral proteins. Such budding reactions usually involve ubiquitin and are blocked by expression of an ATPase-deficient form of VPS4, a cellular AAA+ ATPase believed to be required late in the MVB pathway for the disassembly/release of the MVB machinery. Here we examined the role of the MVB pathway in the budding of the late-domain-containing rhabdovirus vesicular stomatitis virus (VSV) and the alphavirus Semliki Forest virus (SFV). We tested early and late steps in the MVB pathway by depleting ubiquitin with the proteasome inhibitor MG-132 and by using cell lines inducibly expressing VPS4A or VPS4B protein. As previously shown, VSV budding was strongly dependent on ubiquitin. In contrast to the findings of previous studies with VPS4A, expression of ATPase-deficient mutants of either VPS4A or VPS4B inhibited VSV budding. Inhibition by VPS4 required the presence of the PPPY late domain on the VSV matrix protein and resulted in the accumulation of nonreleased VSV particles at the plasma membrane. In contrast, SFV budding was independent of both ubiquitin and the activity of VPS4, perhaps reflecting the important role of the highly organized envelope protein lattice during alphavirus budding.
Temperature-Sensitive Mutations in the Putative Herpes Simplex Virus Type 1 Terminase Subunits pU
L
15 and pU
L
33 Preclude Viral DNA Cleavage/Packaging and Interaction with pU
L
28 at the Nonpermissive Temperature
Authors: Yang Kui , Poon Alice P. W. , Roizman Bernard , Baines Joel D. 
Published: October 2007

ABSTRACT

Terminases comprise essential components of molecular motors required to package viral DNA into capsids in a variety of DNA virus systems. Previous studies indicated that the herpes simplex virus type 1 U
L
15 protein (pU
L
15) interacts with the pU
L
28 moiety of a pU
L
28-pU
L
33 complex to form the likely viral terminase. In the current study, a novel temperature-sensitive mutant virus was shown to contain a mutation in U
L
33 codon 61 predicted to change threonine to proline. At the nonpermissive temperature, this virus, designated ts8-22, replicated viral DNA and produced capsids that became enveloped at the inner nuclear membrane but failed to form plaques or to cleave or package viral DNA. Incubation at the nonpermissive temperature also precluded coimmunoprecipitation of U
L
33 protein with its normal interaction partners encoded by U
L
28 and U
L
15 in ts8-22-infected cells and with pU
L
28 in transient-expression assays. Moreover, a temperature-sensitive mutation in U
L
15 precluded coimmunoprecipitation of pU
L
15 with the U
L
28 and U
L
33 proteins at the nonpermissive temperature. We conclude that interactions between putative terminase components are tightly linked to successful viral DNA cleavage and packaging.
ON TWO THEOREMS OF QUINZII AND RENT CONTROLLED HOUSING ALLOCATION IN SWEDEN
Authors: ERIKSSON KIMMO , SJÖSTRAND JONAS 
Published: October 2007

The Swedish rent control system creates a white market for swapping rental contracts and a black market for selling rental contracts. Empirical data suggests that in this black-and-white market some people act according to utility functions that are both discontinuous and locally decreasing in money. We discuss Quinzii's theorem for the nonemptiness of the core of generalized house-swapping games, and show how it can be extended to cover the Swedish game. In a second part, we show how this theorem of Quinzii and her second theorem on nonemptiness of the core in two-sided models are both special cases of a more general theorem.
Inactivation of NF-κB by 3,3′-diindolylmethane contributes to increased apoptosis induced by chemotherapeutic agent in breast cancer cells
Authors: Rahman KM Wahidur , Ali Shadan , Aboukameel Amro , Sarkar Sanila H. , Wang Zhiwei , Philip Philip A. , Sakr Wael A. , Raz Avraham 
Published: October 2007

AbstractConstitutive activation of Akt or nuclear factor-κB (NF-κB) has been reported to play a role in de novo resistance of cancer cells to chemotherapeutic agents, which is a major cause of treatment failure in cancer chemotherapy. Previous studies have shown that 3,3′-diindolylmethane (DIM), a major in vivo acid-catalyzed condensation product of indole-3-carbinol, is a potent inducer of apoptosis, inhibitor of tumor angiogenesis, and inactivator of Akt/NF-κB signaling in breast cancer cells. However, little is known regarding the inactivation of Akt/NF-κB that leads to chemosensitization of breast cancer cells to chemotherapeutic agents, such as Taxotere. Therefore, we examined whether the inactivation Akt/NF-κB signaling caused by B-DIM could sensitize breast cancer cells to chemotherapeutic agents both in vitro and in vivo. MDA-MB-231 cells were simultaneously treated with 15 to 45 μmol/L B-DIM and 0.5 to 1.0 nmol/L Taxotere for 24 to 72 h. Cell growth inhibition assay, apoptosis assay, electrophoretic mobility shift assay, and Western blotting were done. The combination treatment of 30 μmol/L B-DIM with 1.0 nmol/L Taxotere elicited significantly greater inhibition of cell growth compared with either agent alone. The combination treatment induced greater apoptosis in MDA-MB-231 cells compared with single agents. Moreover, we found that NF-κB activity was significantly decreased in cells treated with B-DIM and Taxotere. We also have tested our hypothesis using transfection studies, followed by combination treatment with B-DIM/Taxotere, and found that combination treatment significantly inhibited cell growth and induced apoptosis in MDA-MB-231 breast cancer cells mediated by the inactivation of NF-κB, a specific target in vitro and in vivo. These results were also supported by animal experiments, which clearly showed that B-DIM sensitized the breast tumors to Taxotere, which resulted in greater antitumor activity mediated by the inhibition of Akt and NF-κB. Collectively, our results clearly suggest that inhibition of Akt/NF-κB signaling by B-DIM leads to chemosensitization of breast cancer cells to Taxotere, which may contribute to increased growth inhibition and apoptosis in breast cancer cells. The data obtained from our studies could be a novel breakthrough in cancer therapeutics by using nontoxic agents, such as B-DIM, in combination with other conventional therapeutic agents, such as Taxotere. [Mol Cancer Ther 2007;6(10):2757–65]
A new species of the genus Physalaemus Fitzinger, 1826 (Anura, Leiuperidae) from Southeastern Brazil
Authors: Gonçalves Cruz Carlos Albert , Barreto Nascimento Luciana , Neves Feio Renato 
Published: October 2007

Abstract
A new species of the genus Physalaemus from the Atlantic Rain Forest of the
state of Minas Gerais is described. It belongs to P. signifer species group
and is characterized by well-developed vocal sac, second finger with the
same size of the fourth, granulate dorsal skin, large inguinal gland with
black ocelli, presence of dorso-lateral folds, and advertisement call
composed by harmonic notes, generally four, being the last shorter than the
others. Information on tadpole external morphology are also presented.
Altitudinal variation in reproductive strategy of the toad-headed lizard, Phrynocephalus vlangalii in North Tibet Plateau (Qinghai)
Authors: Jin Yuan-Ting , Liu Nai-Fa 
Published: October 2007

AbstractPhrynocephalus vlangalii, a toad-headed viviparous sand lizard, is endemic in the Northern Tibet (Qinghai) Plateau in China. Lizards were collected from 14 localities along the large altitudinal gradient (2289-4565 m a.s.l) to analyze the variation of reproductive traits among localities. Both litter size and mean offspring (scaled embryo) mass were positively correlated with female snout-vent length (SVL). Females produced fewer and larger offspring with increasing elevation when the effect of body size (SVL) was removed. This strategy may possibly be correlated with early survival and growth of offspring. The decreased litter size cline along altitudinal gradient might be correlated with more anatomical constraints at higher altitudes. The lizard has lower coefficient of variation (CV) of litter size at higher environments. Moreover, females from higher elevations had less reproductive investment (relative litter mass, RLM). Study concluded that P. vlangalii fit into the common pattern of higher elevation animals that have smaller clutches of larger offspring and lower reproductive effort.
Seasonal variation in the diet of a population of Hyla arborea from Romania
Authors: Kovács Éva-Hajnalka , Sas István , Covaciu-Marcov Severus-Daniel , Hartel Tibor , Cupsa Diana , Groza Marius 
Published: October 2007

Abstract
We examined the diet of Hyla arborea over its entire activity period (March
to late September, 2004), and analysed a total of 585 adult samples. From
the stomach contents we identified plant remains, shed-skin fragments, and
animals. We identified a total of 2976 prey items, almost all of which
originated from the terrestrial environment. Adult araneans and coleopterans
were the most abundant prey items in the diet of the studied tree frogs.
Some of the prey items become abundant in certain parts of the year (e.g.
Homoptera, Lepidoptera larvae, Trichoptera). The dietary diversity index is
high and exhibits seasonal changes. During the period of study an important
seasonal change was observed in feeding intensity and in the type of
consumed prey. Our results show that Hyla arborea has a broad dietary
diversity which was expected as a consequence of exploiting the habitat both
vertically and horizontally, possibly allowing access to a broader spectrum
of prey.
Studies on specialized epidermal derivatives in igianian lizards. I. Gross morphology, topography and histology of callose scales in the Asian Rock Agama, Laudakia himalayana (Steindachner, 1869) (Squamata: Agamidae)
Authors: Dujsebayeva Tatjana , Ananjeva Natalia , Miroschnichenko Larissa 
Published: October 2007

AbstractThe integument of juvenile, yearling and adult specimens of the Asian Rock Agama, Laudakia himalayana from the Western Pamir Mountains has been studied. Different degree of callose scale development was recorded in all groups of specimens. There are sexually dimorphic and age differences in their grossform, number and topography. The results are discussed with reference to available ecological and behavioral data concerning agamids and other lacertilian clades.
Expression and water calcium dependence of calcium transporter isoforms in zebrafish gill mitochondrion-rich cells
Authors: Liao Bo-Kai , Deng Ang-Ni , Chen Shyh-Chi , Chou Ming-Yi , Hwang Pung-Pung 
Published: October 2007

Abstract

Background
Freshwater fish absorb Ca2+ predominantly from ambient water, and more than 97% of Ca2+ uptake is achieved by active transport through gill mitochondrion-rich (MR) cells. In the current model for Ca2+ uptake in gill MR cells, Ca2+ passively enters the cytosol via the epithelium Ca2+ channel (ECaC), and then is extruded into the plasma through the basolateral Na+/Ca2+ exchanger (NCX) and plasma membrane Ca2+-ATPase (PMCA). However, no convincing molecular or cellular evidence has been available to support the role of specific PMCA and/or NCX isoforms in this model. Zebrafish (Danio rerio) is a good model for analyzing isoforms of a gene because of the plentiful genomic databases and expression sequence tag (EST) data.

Results
Using a strategy of BLAST from the zebrafish genome database (Sanger Institute), 6 isoforms of PMCAs (PMCA1a, PMCA1b, PMCA2, PMCA3a, PMCA3b, and PMCA4) and 7 isoforms of NCXs (NCX1a, NCX1b, NCX2a, NCX2b, NCX3, NCX4a, and NCX4b) were identified. In the reverse-transcriptase polymerase chain reaction (RT-PCR) analysis, 5 PMCAs and 2 NCXs were ubiquitously expressed in various tissues including gills. Triple fluorescence in situ hybridization and immunocytochemistry showed the colocalization of zecac, zpmca2, and zncx1b mRNAs in a portion of gill MR cells (using Na+-K+-ATPase as the marker), implying a subset of ionocytes specifically responsible for the transepithelial Ca2+ uptake in zebrafish gills. The gene expressions in gills of high- or low-Ca2+-acclimated zebrafish by quantitative real-time PCR analysis showed that zecac was the only gene regulated in response to environmental Ca2+ levels, while zpmcas and zncxs remained steady.

Conclusion
The present study provides molecular evidence for the specific isoforms of Ca2+ transporters, zECaC, zPMCA2, and zNCX1b, supporting the current Ca2+ uptake model, in which ECaC may play a role as the major regulatory target for this mechanism during environmental challenge.
A pilot study on pupillary and cardiovascular changes induced by stereoscopic video movies
Authors: Oyamada Hiroshi , Iijima Atsuhiko , Tanaka Akira , Ukai Kazuhiko , Toda Haruo , Sugita Norihiro , Yoshizawa Makoto , Bando Takehiko 
Published: October 2007

Abstract

Background
Taking advantage of developed image technology, it is expected that image presentation would be utilized to promote health in the field of medical care and public health. To accumulate knowledge on biomedical effects induced by image presentation, an essential prerequisite for these purposes, studies on autonomic responses in more than one physiological system would be necessary. In this study, changes in parameters of the pupillary light reflex and cardiovascular reflex evoked by motion pictures were examined, which would be utilized to evaluate the effects of images, and to avoid side effects.

Methods
Three stereoscopic video movies with different properties were field-sequentially rear-projected through two LCD projectors on an 80-inch screen. Seven healthy young subjects watched movies in a dark room. Pupillary parameters were measured before and after presentation of movies by an infrared pupillometer. ECG and radial blood pressure were continuously monitored. The maximum cross-correlation coefficient between heart rate and blood pressure, ρmax, was used as an index to evaluate changes in the cardiovascular reflex.

Results
Parameters of pupillary and cardiovascular reflexes changed differently after subjects watched three different video movies. Amplitudes of the pupillary light reflex, CR, increased when subjects watched two CG movies (movies A and D), while they did not change after watching a movie with the real scenery (movie R). The ρmax was significantly larger after presentation of the movie D. Scores of the questionnaire for subjective evaluation of physical condition increased after presentation of all movies, but their relationship with changes in CR and ρmax was different in three movies. Possible causes of these biomedical differences are discussed.

Conclusion
The autonomic responses were effective to monitor biomedical effects induced by image presentation. Further accumulation of data on multiple autonomic functions would contribute to develop the tools which evaluate the effects of image presentation to select applicable procedures and to avoid side effects in the medical care and rehabilitation.
Finding disease candidate genes by liquid association
Authors: Li Ker-Chau , Palotie Aarno , Yuan Shinsheng , Bronnikov Denis , Chen Daniel , Wei Xuelian , Choi Oi-Wa , Saarela Janna , Peltonen Leena 
Published: October 2007

AbstractA novel approach to finding candidate genes by using gene expression data through liquid association is developed and used to identify multiple sclerosis susceptibility candidate genes.