bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cathepsin B Mediates Cleavage of Herpes Simplex Virus Type 1 Origin Binding Protein (OBP) To Yield OBPC-1, and Cleavage Is Dependent upon Viral DNA Replication
Authors: Link Malen A. , Silva Laurie A. , Schaffer Priscilla A. 
Published: June 2007

ABSTRACT
Although the seven viral proteins required for herpes simplex virus type 1 (HSV-1) DNA replication have been identified, the mechanism by which viral DNA synthesis is regulated is unclear. HSV-1 DNA replication is thought to occur in two stages: origin-dependent DNA replication (stage I) mediated by the origin binding protein (OBP), followed by origin- and OBP-independent DNA replication (stage II). The mechanism that facilitates the switch from stage I to stage II is unknown; however, it must involve the loss of OBP function or OBP itself from the replication initiation complex. Previous studies from this laboratory identified a transcript (UL8.5) and protein (OBPC) that are in frame with and comprise the C terminus of the gene specifying OBP. Because of its DNA binding ability, OBPC has been hypothesized to mediate the switch from stage I to stage II. Here, we identify a second protein (OBPC-2) that is also in frame with the C terminus of OBP but comprises a smaller portion of the protein. We demonstrate that the protein originally identified (OBPC-1) is a cathepsin B-mediated cleavage product of OBP, while OBPC-2 may be the product of the UL8.5 transcript. We further demonstrate that the cleavage of OBP to yield OBPC-1 is dependent upon viral DNA replication. These results suggest that cleavage may be a mechanism by which OBP levels and/or activity are regulated during infection.
Caveolar Endocytosis Is Critical for BK Virus Infection of Human Renal Proximal Tubular Epithelial Cells
Authors: Moriyama Takahito , Marquez J. Pablo , Wakatsuki Tetsuro , Sorokin Andrey 
Published: June 2007

ABSTRACT
In recent years, BK virus (BKV) nephritis after renal transplantation has become a severe problem. The exact mechanisms of BKV cell entry and subsequent intracellular trafficking remain unknown. Since human renal proximal tubular epithelial cells (HRPTEC) represent a main natural target of BKV nephritis, analysis of BKV infection of HRPTEC is necessary to obtain additional insights into BKV biology and to develop novel strategies for the treatment of BKV nephritis. We coincubated HRPTEC with BKV and the cholesterol-depleting agents methyl beta cyclodextrin (MBCD) and nystatin (Nys), drugs inhibiting caveolar endocytosis. The percentage of infected cells (detected by immunofluorescence) and the cellular levels of BKV large T antigen expression (detected by Western blot analysis) were significantly decreased in both MBCD- and Nys-treated HPRTEC compared to the level in HRPTEC incubated with BKV alone. HRPTEC infection by BKV was also tested after small interfering RNA (siRNA)-dependent depletion of either the caveolar structural protein caveolin-1 (Cav-1) or clathrin, the major structural protein of clathrin-coated pits. BKV infection was inhibited in HRPTEC transfected with Cav-1 siRNA but not in HRPTEC transfected with clathrin siRNA. The colocalization of labeled BKV particles with either Cav-1 or clathrin was investigated by using fluorescent microscopy and image cross-correlation spectroscopy. The rate of colocalization of BKV with Cav-1 peaked at 4 h after incubation. Colocalization with clathrin was insignificant at all time points. These results suggest that BKV entered into HRPTEC via caveolae, not clathrin-coated pits, and that BKV is maximally associated with caveolae at 4 h after infection, prior to relocation to a different intracellular compartment.
Proline 35 of Human Immunodeficiency Virus Type 1 (HIV-1) Vpr Regulates the Integrity of the N-Terminal Helix and the Incorporation of Vpr into Virus Particles and Supports the Replication of R5-Tropic HIV-1 in Human Lymphoid Tissue Ex Vivo
Authors: Votteler Jörg , Studtrucker Nicole , Sörgel Stefan , Münch Jan , Rücker Elke , Kirchhoff Frank , Schick Bernhard , Henklein Peter , Fossen Torgils , Bruns Karsten , Sharma Alok , Wray Victor , Schubert Ulrich 
Published: June 2007

ABSTRACT

Mutational analysis of the four conserved proline residues in human immunodeficiency virus type 1 (HIV-1) Vpr reveals that only Pro-35 is required for efficient replication of R5-tropic, but not of X4-tropic, viruses in human lymphoid tissue (HLT) cultivated ex vivo. While Vpr-mediated apoptosis and G
2
cell cycle arrest, as well as the expression and subcellular localization of Vpr, were independent, the capacity for encapsidation of Vpr into budding virions was dependent on Pro-35.
1
H nuclear magnetic resonance data suggest that mutation of Pro-35 causes a conformational change in the hydrophobic core of the molecule, whose integrity is required for the encapsidation of Vpr, and thus, Pro-35 supports the replication of R5-tropic HIV-1 in HLT.
Nonlinear Mean Ergodic Theorems for Semigroups in Hilbert Spaces
Authors: Temir Seyit , Gul Ozlem 
Published: June 2007

AbstractLet "Equation missing" be a nonempty subset (not necessarily closed and convex) of a Hilbert space and let "Equation missing" be a semigroup on "Equation missing" and let "Equation missing" be an almost orbit of "Equation missing". In this paper, we prove that every almost orbit of "Equation missing" is almost weakly and strongly convergent to its asymptotic center.
Prostate Cancer Associated with p53 and Rb Deficiency Arises from the Stem/Progenitor Cell–Enriched Proximal Region of Prostatic Ducts
Authors: Zhou Zongxiang , Flesken-Nikitin Andrea , Nikitin Alexander Yu. 
Published: June 2007

Abstract
Recently, we have shown that prostate epithelium–specific deficiency for p53 and Rb tumor suppressors leads to metastatic cancer, exhibiting features of both luminal and neuroendocrine differentiation. Using stage-by-stage evaluation of carcinogenesis in this model, we report that all malignant neoplasms arise from the proximal region of the prostatic ducts, the compartment highly enriched for prostatic stem/progenitor cells. In close similarity to reported properties of prostatic stem cells, the cells of the earliest neoplastic lesions express stem cell marker stem cell antigen 1 and are not sensitive to androgen withdrawal. Like a subset of normal cells located in the proximal region of prostatic ducts, the early neoplastic cells coexpress luminal epithelium markers cytokeratin 8, androgen receptor, and neuroendocrine markers synaptophysin and chromogranin A. Inactivation of p53 and Rb also takes place in the lineage-committed transit-amplifying and/or differentiated cells of the distal region of the prostatic ducts. However, the resulting prostatic intraepithelial neoplasms never progress to carcinoma by the time of mouse death. Interestingly, in an ectopic transplantation assay, early mutant cells derived from either region of the prostatic ducts are capable of forming neoplasms within 3 months. These findings indicate that p53 and Rb are critically important for the regulation of the prostatic stem cell compartment, the transformation in which may lead to particularly aggressive cancers in the context of microenvironment. [Cancer Res 2007;67(12):5683–90]
Direct interaction between Kit and the interleukin-7 receptor
Authors: Jahn Thomas , Sindhu Simran , Gooch Stacie , Seipel Petra , Lavori Philip , Leifheit Erica , Weinberg Kenneth 
Published: June 2007

AbstractIn vivo analyses of thymopoiesis in mice defective in signaling through Kit and γc or Kit and IL-7Rα demonstrate synergy and partial complementation of γc or IL-7–mediated signaling by the Kit signaling pathway. Our molecular analysis in T-lymphoid cells as well as in nonhematopoietic cells shows that Kit and IL-7R signaling pathways directly interact. KL-mediated activation of Kit induced strong tyrosine phosphorylation of γc and IL-7Rα in the absence of IL-7. Activated Kit formed a complex with either IL-7Rα or γc, and tyrosine phosphorylation of both subunits occurred independently of Jak3, suggesting that γc and IL-7Rα are each direct substrates of Kit. Kit activated Jak3 in an IL-7R–dependent manner. Moreover, deficient Stat5 activation of the Kit mutant YY567/569FF lacking intrinsic Src activation capacity was partially reconstituted in the presence of IL-7R and Jak3. Based on the molecular data, we propose a model of Kit-mediated functional activation of γc-containing receptors such as IL-7R, similar to the interaction between Kit and Epo-R. Such indirect activation of the Jak-Stat pathway induced by the interaction between an RTK and type I cytokine receptor could be the underlying mechanism for a context-specific signaling repertoire of a pleiotropic RTK-like Kit.
Factor H–mediated cell surface protection from complement is critical for the survival of PNH erythrocytes
Authors: Ferreira Viviana P. , Pangburn Michael K. 
Published: June 2007

AbstractParoxysmal nocturnal hemoglobinuria (PNH) cells are partially (type II) or completely (type III) deficient in GPI-linked complement regulatory proteins CD59 and CD55. PNH III erythrocytes circulate 6 to 60 days in vivo. Why these cells are not lysed as rapidly by complement as unprotected foreign cells, which normally lyse within minutes, remains undetermined. Factor H plays a key role in the homeostasis of complement in fluid phase and on cell surfaces. We have recently shown that a recombinant protein encompassing the C-terminus of factor H (rH19-20) specifically blocks cell-surface complement regulatory functions of factor H without affecting fluid-phase control of complement. Here we show that PNH II and III cells become highly susceptible to complement-mediated lysis by nonacidified normal human serum in vitro, when the cell surface complement-regulatory functions of factor H are blocked. The results indicate that cells deficient in surface-bound regulators are protected for extended periods of time by factor H.
A mitogenomic approach to the taxonomy of pollocks: Theragra chalcogramma and T. finnmarchica represent one single species
Authors: Ursvik Anita , Breines Ragna , Christiansen Jørgen Schou , Fevolden Svein-Erik , Coucheron Dag H , Johansen Steinar D 
Published: June 2007

Abstract

Background
The walleye pollock (Theragra chalcogramma) and Norwegian pollock (T. finnmarchica) are confined to the North Pacific and North Atlantic Oceans, respectively, and considered as distinct species within the family Gadidae. We have determined the complete mtDNA nucleotide sequence of two specimens of Norwegian pollock and compared the sequences to that of 10 specimens of walleye pollock representing stocks from the Sea of Japan and the Bering Sea, 2 specimens of Atlantic cod (Gadus morhua), and 2 specimens of haddock (Melanogrammus aeglefinus).

Results
A total number of 204 variable positions were identified among the 12 pollock specimens, but no specific substitution pattern could be identified between the walleye and Norwegian pollocks. Phylogenetic analysis using 16.500 homologous mtDNA nucleotide positions clearly identify the Norwegian pollock within the walleye pollock species cluster. Furthermore, the Norwegian pollock sequences were most similar to mitochondrial genotypes present in walleye pollock specimens from the Sea of Japan, an observation supported both by neighbor-joining, maximum parsimony, and maximum likelihood analyses.

Conclusion
We infer that walleye pollock and Norwegian pollock represent one single species and that Norwegian pollock has been recently introduced from the Pacific to the Atlantic Oceans.
Microbial larvicides for malaria control in The Gambia
Authors: Majambere Silas , Lindsay Steven W , Green Clare , Kandeh Balla , Fillinger Ulrike 
Published: June 2007

Abstract

Background
Mosquito larval control may prove to be an effective tool for incorporating into integrated vector management (IVM) strategies for reducing malaria transmission. Here the efficacy of microbial larvicides against Anopheles gambiae s.l. was tested in preparation for a large-scale larviciding programme in The Gambia.

Methods
The impact of water-dispersible (WDG) and corn granule (CG) formulations of commercial Bacillus sphaericus strain 2362 (Bs; VectoLex®) and Bacillus thuringiensis var.israelensis strain AM65-52 (Bti; VectoBac®) on larval development were tested under laboratory and field conditions to (1) identify the susceptibility of local vectors, (2) evaluate the residual effect and re-treatment intervals, (3) test the effectiveness of the microbials under operational application conditions and (4) develop a method for large-scale application.

Results
The major malaria vectors were highly susceptible to both microbials. The lethal concentration (LC) to kill 95% of third instar larvae of Anopheles gambiae s.s. after 24 hours was 0.023 mg/l (14.9 BsITU/l) for Bs WDG and 0.132 mg/l (396 ITU/l) for Bti WDG. In general Bs had little residual effect under field conditions even when the application rate was 200 times greater than the LC95. However, there was a residual effect up to 10 days in standardized field tests implemented during the dry season. Both microbials achieved 100% mortality of larvae 24–48 hours post-application but late instar larvae were detected 4 days after treatment. Pupae development was reduced by 94% (95% Confidence Interval = 90.8–97.5%) at weekly re-treatment intervals. Field tests showed that Bs had no residual activity against anopheline larvae. Both microbials provided complete protection when applied weekly. The basic training of personnel in identification of habitats, calibration of application equipment and active larviciding proved to be successful and achieved full coverage and control of mosquito larvae for three months under fully operational conditions.

Conclusion
Environmentally safe microbial larvicides can significantly reduce larval abundance in the natural habitats of The Gambia and could be a useful tool for inclusion in an IVM programme. The costs of the intervention in this setting could be reduced with formulations that provide a greater residual effect.
Human neuronal cell protein responses to Nipah virus infection
Authors: Chang Li-Yen , Ali AR Mohd , Hassan Sharifah Syed , AbuBakar Sazaly 
Published: June 2007

Abstract

Background
Nipah virus (NiV), a recently discovered zoonotic virus infects and replicates in several human cell types. Its replication in human neuronal cells, however, is less efficient in comparison to other fully susceptible cells. In the present study, the SK-N-MC human neuronal cell protein response to NiV infection is examined using proteomic approaches.

Results
Method for separation of the NiV-infected human neuronal cell proteins using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) was established. At least 800 protein spots were resolved of which seven were unique, six were significantly up-regulated and eight were significantly down-regulated. Six of these altered proteins were identified using mass spectrometry (MS) and confirmed using MS/MS. The heterogenous nuclear ribonucleoprotein (hnRNP) F, guanine nucleotide binding protein (G protein), voltage-dependent anion channel 2 (VDAC2) and cytochrome bc1 were present in abundance in the NiV-infected SK-N-MC cells in contrast to hnRNPs H and H2 that were significantly down-regulated.

Conclusion
Several human neuronal cell proteins that are differentially expressed following NiV infection are identified. The proteins are associated with various cellular functions and their abundance reflects their significance in the cytopathologic responses to the infection and the regulation of NiV replication. The potential importance of the ratio of hnRNP F, and hnRNPs H and H2 in regulation of NiV replication, the association of the mitochondrial protein with the cytopathologic responses to the infection and induction of apoptosis are highlighted.
Cyclooxygenase activity is important for efficient replication of mouse hepatitis virus at an early stage of infection
Authors: Raaben Matthijs , Einerhand Alexandra WC , Taminiau Lucas JA , van Houdt Michel , Bouma Janneke , Raatgeep Rolien H , Büller Hans A , de Haan Cornelis AM , Rossen John WA 
Published: June 2007

AbstractCyclooxygenases (COXs) play a significant role in many different viral infections with respect to replication and pathogenesis. Here we investigated the role of COXs in the mouse hepatitis coronavirus (MHV) infection cycle. Blocking COX activity by different inhibitors or by RNA interference affected MHV infection in different cells. The COX inhibitors reduced MHV infection at a post-binding step, but early in the replication cycle. Both viral RNA and viral protein synthesis were affected with subsequent loss of progeny virus production. Thus, COX activity appears to be required for efficient MHV replication, providing a potential target for anti-coronaviral therapy.
Polymorphonuclear leukocyte transverse migration induces rapid alterations in endothelial focal contacts
Authors: Su Wen-Hong , Chen Hsiun-ing , Jen Chauying J 
Published: June 2007

AbstractTransmigrated polymorphonuclear leukocytes (PMNs) usually undergo subendothelial transverse migration before penetrating into inner tissue layers. Whether or how endothelial cells (ECs) respond to the PMN migrating underneath them is unknown. A tissue flow chamber was used to establish a fMLP gradient and to observe PMN transverse migration along with its associated endothelial responses in culture (on a collagen gel) or in vascular tissues. Our results indicated that transversely migrating PMNs were in direct contact with the basal side of ECs. Contrasting to focal adhesion kinase (FAK) or proteins with phosphorylated tyrosine, paxillin disappeared rapidly (&lt;1 min) from endothelial focal contacts afterencountering the leukocyte’s leading edge and soon rejoined them after the PMN had left. In addition, FAK moved away or became dephosphorylated when PMNs remained at the same subendothelial location for longer than 10 min, leaving actin filaments apparently unaltered. Unlike PMN transendothelial migration, PMN transverse migration did not induce any detectable endothelial calcium signaling. Taken together, our findings indicated that PMN transverse migration interrupted endothelial-matrix interactions and induced rapid alterations in endothelial focal contact composition.
IL-21 promotes T lymphocyte survival by activating the phosphatidylinositol-3 kinase signaling cascade
Authors: Ostiguy Valérie , Allard Ève-Line , Marquis Miriam , Leignadier Julie , Labrecque Nathalie 
Published: June 2007

AbstractIL21 is a Type I cytokine, which uses the common γ chain (γc) in its receptor. As members of the γc cytokine/cytokine receptors family play crucial role in the differentiation, activation, and survival of lymphocytes, we have investigated if IL-21 could promote T cell survival and thus, contribute to T cell homeostasis and expansion. Unlike most γc cytokine receptors, we report that IL-21R is constitutively expressed by all mature T lymphocytes and that stromal cells of lymphoid organs are a constitutive source of IL-21. These observations are reminiscent of what is observed for IL-7/IL-7R, which control T cell survival and homeostasis and suggest a role for IL-21 in T cell homeostasis. Indeed, our results show that IL-21 is a survival factor for resting and activated T cells. Moreover, the ability of IL-21 to costimulate T cell proliferation is mediated by enhancing T cell viability. Further investigation of how IL-21R signaling induces T cell survival shows for the first time that IL-21 binding to its receptor activates the PI-3K signaling pathway and induces Bcl-2 expression. Moreover, the activation of the PI-3K signaling pathway is essential for IL-21-mediated T cell survival. Our data provide a new role for IL-21 in the immune system, which might be used to improve T cell homeostasis in immunocompromised patients.
Objective measurement of physical activity in Macaca fascicularis
Authors: Corbett Wayne T. , Schey Harry M. , Green A. W. 
Published: June 2007

The mean and standard deviation over 24 h for 3 groups of animals - active, intermediate and inactive - in physical activity units were 10948 ± 3360, 2611 ± 1973 and 484 ± 316 respectively. The differences were significant ( P = 0·004), demonstrating the ability of the method to distinguish between groups that can be visibly differentiated. The small within-animal physical activity standard deviation (18·85 PAU) obtained in another group, suggests that it also yields reliable physical activity measurements for non-human primates. The monitoring device used can discriminate between individual nonhuman primate physical activity levels in a free-living environment and does not alter daily behaviour. This makes possible the study of the relationship between physical activity and atherosclerosis in nonhuman primates.
Transmission of B virus infection between monkeys especially in relation to breeding colonies
Authors: Zwartouw H. T. , MacArthur Judy A. , Boulter E. A. , Seamer J. H. , Marston J. H. , Chamove A. S. 
Published: June 2007

Studies of B virus ( Herpesvirus simiae) antibody in several species of macaque lead to the following generalizations. Newborn monkeys are not infected with B virus, even when born of seropositive mothers. Young monkeys remain uninfected until they become adults. The majority of adults develop B virus antibody unless their physical contact with seropositive adults is restricted. These observations are consistent with sexual transmission of B virus and classification of the disease in monkeys as venereal. However, infection at oral and dermal sites also occurs and may play a part in monkey-to-monkey transmission. Epizootics of B virus occurred during early attempts to start B virus-free breeding colonies. They appeared to originate from reactivated latent B virus in adult monkeys which had only low titres of antibody. The stress produced when groups of adult strangers were assembled to form breeding colonies was the most effective known inducer of latent B virus. Total exclusion of animals with any trace of antibody has enabled the establishment of new breeding colonies which are free from B virus.
The use of lignocaine-prilocaine local anaesthetic cream for pain-free venepuncture in laboratory animals
Authors: Flecknell P. A. , Liles J. H. , Williamson H. A. 
Published: June 2007

An assessment was made of the effects of topical application of a eutectic mixture of local anaesthetics (EMLA cream) in a number of species of laboratory animals. Application of EMLA cream enabled percutaneous insertion of catheters into the cephalic vein in dogs and cats and the marginal ear vein in rabbits without causing any detectable pain or discomfort. Application to the tail in rats prior to percutaneous cannulation of the lateral tail vein did not produce a significant reduction in the behavioural responses to venepuncture. EMLA cream represents a useful refinement of current techniques for intravenous injection in some species, and is especially valuable when the procedure is to be undertaken by an inexperienced operator.