bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evidence that the Linker between the Methyltransferase and Helicase Domains of Potato Virus X Replicase Is Involved in Homologous RNA Recombination
Authors: Draghici Heidrun-Katharina , Varrelmann Mark 
Published: May 2009

ABSTRACTRecombination in RNA viruses, one of the main factors contributing to their genetic variability and evolution, is a widespread phenomenon. In this study, an in vivo assay to characterize RNA recombination in potato virus X (PVX), under high selection pressure, was established.Agrobacterium tumefacienswas used to express inNicotiana benthamianaleaf tissue both a PVX isolate labeled with green fluorescent protein (GFP) containing a coat protein deletion mutation (ΔCP) and a transcript encoding a functional coat protein +3′-ntr. Coexpression of the constructs led to virus movement and systemic infection; reconstituted recombinants were observed in 92% of inoculated plants. Similar results were obtained using particle bombardment, demonstrating that recombination mediated byA. tumefacienswas not responsible for the occurrence of PXC recombinants. The speed of recombination could be estimated by agroinfection of two PVX mutants lacking the 3′ and 5′ halves of the genome, respectively, with an overlap in the triple gene block 1 gene, allowing GFP expression only in the case of recombination. Ten different pentapeptide insertion scanning replicase mutants with replication abilities comparable to wild-type virus were applied in the different recombination assays. Two neighboring mutants affecting the linker between the methyltransferase and helicase domains were shown to be strongly debilitated in their ability to recombine. The possible functional separation of replication and recombination in the replicase molecule supports the model that RNA recombination represents a distinct function of this protein, although the underlying mechanism still needs to be investigated.
The M33 Chemokine Receptor Homolog of Murine Cytomegalovirus Exhibits a Differential Tissue-Specific Role during In Vivo Replication and Latency
Authors: Cardin Rhonda D. , Schaefer Gregory C. , Allen Janelle R. , Davis-Poynter Nicholas J. , Farrell Helen E. 
Published: May 2009

ABSTRACT

M33, encoded by murine cytomegalovirus (MCMV), is a member of the UL33 homolog G-protein-coupled receptor (GPCR) family and is conserved across all the betaherpesviruses. Infection of mice with recombinant viruses lacking M33 or containing specific signaling domain mutations in M33 results in significantly diminished MCMV infection of the salivary glands. To determine the role of M33 in viral dissemination and/or infection in other tissues, viral infection with wild-type K181 virus and an M33 mutant virus, ΔM33B
T2
, was characterized using two different routes of inoculation. Following both intraperitoneal (i.p.) and intranasal (i.n.) inoculation, M33 was attenuated for infection of the spleen and pancreas as early as 7 days after infection. Following i.p. inoculation, ΔM33B
T2
exhibited a severe defect in latency as measured by a diminished capacity to reactivate from spleens and lungs in reactivation assays (
P
< 0.001). Subsequent PCR analysis revealed markedly reduced ΔM33B
T2
viral DNA levels in the latently infected spleens, lungs, and bone marrow. Following i.n. inoculation, latent ΔM33B
T2
viral DNA was significantly reduced in the spleen and, in agreement with results from i.p. inoculation, did not reactivate from the spleen (
P
< 0.001). Furthermore, in vivo complementation of ΔM33B
T2
virus replication and/or dissemination to the salivary glands and pancreas was achieved by coinfection with wild-type virus. Overall, our data suggest a critical tissue-specific role for M33 during infection in the salivary glands, spleen, and pancreas but not the lungs. Our data suggest that M33 contributes to the efficient establishment or maintenance of long-term latent MCMV infection.
Latency-Associated Nuclear Antigen of Kaposi's Sarcoma-Associated Herpesvirus (KSHV) Upregulates Survivin Expression in KSHV-Associated B-Lymphoma Cells and Contributes to Their Proliferation
Authors: Lu Jie , Verma Subhash C. , Murakami Masanao , Cai Qiliang , Kumar Pankaj , Xiao Bingyi , Robertson Erle S. 
Published: May 2009

ABSTRACT

Survivin is a master regulator of cell proliferation and cell viability and is highly expressed in most human tumors. The molecular network linked to survivin expression in tumors has not been completely elucidated. In this study, we show that latency-associated nuclear antigen (LANA), a multifunctional protein of Kaposi's sarcoma-associated herpesvirus (KSHV) that is found in Kaposi's sarcoma tumors, upregulates survivin expression and increases the proliferation of KSHV-infected B cells. Analysis of pathway-specific gene arrays showed that survivin expression was highly upregulated in BJAB cells expressing LANA. The mRNA levels of survivin were also upregulated in HEK 293 and BJAB cells expressing LANA. Similarly, protein levels of survivin were significantly higher in LANA-expressing, as well as KSHV-infected, cells. Survivin promoter activity assays identified GC/Sp1 and p53
cis
-acting elements within the core promoter region as being important for LANA activity. Gel mobility shift assays revealed that LANA forms a complex with Sp1 or Sp1-like proteins bound to the GC/Sp1 box of the survivin promoter. In addition, a LANA/p53 complex bound to the p53
cis
-acting element within the survivin promoter, indicating that upregulation of survivin expression can also occur through suppression of p53 function. Furthermore, immunohistochemistry analyses revealed that survivin expression was upregulated in KSHV-associated Kaposi's sarcoma tissue, suggesting that LANA plays an important role in the upregulation of survivin expression in KSHV-infected endothelial cells. Knockdown of survivin expression by lentivirus-delivered small hairpin RNA resulted in loss of cell proliferation in KSHV-infected cells. Therefore, upregulation of survivin expression in KSHV-associated human cells contributes to their proliferation.
The Fowlpox Virus BCL-2 Homologue, FPV039, Interacts with Activated Bax and a Discrete Subset of BH3-Only Proteins To Inhibit Apoptosis
Authors: Banadyga Logan , Veugelers Kirstin , Campbell Stephanie , Barry Michele 
Published: May 2009

ABSTRACT
Apoptosis is a potent immune barrier against viral infection, and many viruses, including poxviruses, encode proteins to overcome this defense. Interestingly, the avipoxviruses, which include fowlpox and canarypox virus, are the only poxviruses known to encode proteins with obvious Bcl-2 sequence homology. We previously characterized the fowlpox virus protein FPV039 as a Bcl-2-like antiapoptotic protein that inhibits apoptosis by interacting with and inactivating the proapoptotic cellular protein Bak. However, both Bak and Bax can independently trigger cell death. Thus, to effectively inhibit apoptosis, a number of viruses also inhibit Bax. Here we show that FPV039 inhibited apoptosis induced by Bax overexpression and prevented both the conformational activation of Bax and the subsequent formation of Bax oligomers at the mitochondria, two critical steps in the induction of apoptosis. Additionally, FPV039 interacted with activated Bax in the context of Bax overexpression and virus infection. Importantly, the ability of FPV039 to interact with active Bax and inhibit Bax activity was dependent on the structurally conserved BH3 domain of FPV039, even though this domain possesses little sequence homology to other BH3 domains. FPV039 also inhibited apoptosis induced by the BH3-only proteins, upstream activators of Bak and Bax, despite interacting detectably with only two: BimL and Bik. Collectively, our data suggest that FPV039 inhibits apoptosis by sequestering and inactivating multiple proapoptotic Bcl-2 proteins, including certain BH3-only proteins and both of the critical “gatekeepers” of apoptosis, Bak and Bax.
Coronavirus Genetically Redirected to the Epidermal Growth Factor Receptor Exhibits Effective Antitumor Activity against a Malignant Glioblastoma
Authors: Verheije Monique H. , Lamfers Martine L. M. , Würdinger Thomas , Grinwis Guy C. M. , Gerritsen Winald R. , van Beusechem Victor W. , Rottier Peter J. M. 
Published: May 2009

ABSTRACTCoronaviruses are positive-strand RNA viruses with features attractive for oncolytic therapy. To investigate this potential, we redirected the coronavirus murine hepatitis virus (MHV), which is normally unable to infect human cells, to human tumor cells by using a soluble receptor (soR)-based expression construct fused to an epidermal growth factor (EGF) receptor targeting moiety. Addition of this adapter protein to MHV allowed infection of otherwise nonsusceptible, EGF receptor (EGFR)-expressing cell cultures. We introduced the sequence encoding the adaptor protein soR-EGF into the MHV genome to generate a self-targeted virus capable of multiround infection. The resulting recombinant MHV was viable and had indeed acquired the ability to infect all glioblastoma cell lines tested in vitro. Infection of malignant human glioblastoma U87ΔEGFR cells gave rise to release of progeny virus and efficient cell killing in vitro. To investigate the oncolytic capacity of the virus in vivo, we used an orthotopic U87ΔEGFR xenograft mouse model. Treatment of mice bearing a lethal intracranial U87ΔEGFR tumor by injection with MHVsoR-EGF significantly prolonged survival compared to phosphate-buffered saline-treated (P= 0.001) and control virus-treated (P= 0.004) animals, and no recurrent tumor load was observed. However, some adverse effects were seen in normal mouse brain tissues that were likely caused by the natural murine tropism of MHV. This is the first demonstration of oncolytic activity of a coronavirus in vivo. It suggests that nonhuman coronaviruses may be attractive new therapeutic agents against human tumors.
Viruses in the Anopheles A, Anopheles B, and Tete Serogroups in the
Orthobunyavirus
Genus (Family
Bunyaviridae
) Do Not Encode an NSs Protein
Authors: Mohamed Maizan , McLees Angela , Elliott Richard M. 
Published: May 2009

ABSTRACT

Viruses in the genus
Orthobunyavirus
, family
Bunyaviridae
, have a genome comprising three segments (called L, M, and S) of negative-sense RNA. Serological studies have classified the >170 named virus isolates into 18 serogroups, with a few additional as yet ungrouped viruses. Until now, molecular studies and full-length S-segment nucleotide sequences were available for representatives of eight serogroups; in all cases, the S segment encodes two proteins, N (nucleocapsid) and NSs (nonstructural), in overlapping open reading frames (ORFs) that are translated from the same mRNA. The NSs proteins of Bunyamwera virus (BUNV) and California serogroup viruses have been shown to play a role in inhibiting host cell mRNA and protein synthesis, thereby preventing induction of interferon (IFN). We have determined full-length sequences of the S segments of representative viruses in the Anopheles A, Anopheles B, and Tete serogroups, and we report here that these viruses do not show evidence of having an NSs ORF. In addition, these viruses have rather longer N proteins than those in the other serogroups. Most of the naturally occurring viruses that lack the NSs protein behaved like a recombinant BUNV with the NSs gene deleted in that they failed to prevent induction of IFN-β mRNA. However, Tacaiuma virus (TCMV) in the Anopheles A serogroup inhibited IFN induction in a manner similar to that of wild-type BUNV, suggesting that TCMV has evolved an alternative mechanism, not involving a typical NSs protein, to antagonize the host innate immune response.
Home Training, Local Corticosteroid Injection, or Radial Shock Wave Therapy for Greater Trochanter Pain Syndrome
Authors: Rompe Jan D. , Segal Neil A. , Cacchio Angelo , Furia John P. , Morral Antonio , Maffulli Nicola 
Published: May 2009

Background There are no controlled studies testing the efficacy of various nonoperative strategies for treatment of greater trochanter pain syndrome. Hypothesis The null hypothesis was that local corticosteroid injection, home training, and repetitive low-energy shock wave therapy produce equivalent outcomes 4 months from baseline. Study Design Randomized controlled clinical trial; Level of evidence, 2. Methods Two hundred twenty-nine patients with refractory unilateral greater trochanter pain syndrome were assigned sequentially to a home training program, a single local corticosteroid injection (25 mg prednisolone), or a repetitive low-energy radial shock wave treatment. Subjects underwent outcome assessments at baseline and at 1, 4, and 15 months. Primary outcome measures were degree of recovery, measured on a 6-point Likert scale (subjects with rating completely recovered or much improved were rated as treatment success), and severity of pain over the past week (0–10 points) at 4-month follow-up. Results One month from baseline, results after corticosteroid injection (success rate, 75%; pain rating, 2.2 points) were significantly better than those after home training (7%; 5.9 points) or shock wave therapy (13%; 5.6 points). Regarding treatment success at 4 months, radial shock wave therapy led to significantly better results (68%; 3.1 points) than did home training (41%; 5.2 points) and corticosteroid injection (51%; 4.5 points). The null hypothesis was rejected. Fifteen months from baseline, radial shock wave therapy (74%; 2.4 points) and home training (80%; 2.7 points) were significantly more successful than was corticosteroid injection (48%; 5.3 points). Conclusion The role of corticosteroid injection for greater trochanter pain syndrome needs to be reconsidered. Subjects should be properly informed about the advantages and disadvantages of the treatment options, including the economic burden. The significant short-term superiority of a single corticosteroid injection over home training and shock wave therapy declined after 1 month. Both corticosteroid injection and home training were significantly less successful than was shock wave therapy at 4-month follow-up. Corticosteroid injection was significantly less successful than was home training or shock wave therapy at 15-month follow-up.
Endothelial deletion of hypoxia-inducible factor–2α (HIF-2α) alters vascular function and tumor angiogenesis
Authors: Skuli Nicolas , Liu Liping , Runge Anja , Wang Tao , Yuan Lijun , Patel Sunny , Iruela-Arispe Luisa , Simon M. Celeste , Keith Brian 
Published: May 2009

AbstractHypoxia-inducible factor–2α (HIF-2α) is highly expressed in embryonic vascular endothelial cells (ECs) and activates the expression of target genes whose products modulate vascular function and angiogenesis. In this report, we describe a genetic model designed to test the physiologic consequences of deleting HIF-2α in murine endothelial cells. Surprisingly, mice with HIF-2α–deficient ECs developed normally but displayed a variety of phenotypes, including increased vessel permeability, aberrant endothelial cell ultrastructure, and pulmonary hypertension. Moreover, these animals exhibited defective tumor angiogenesis associated with increased hypoxic stress and tumor cell apoptosis. Immortalized HIF-2α–deficient ECs displayed decreased adhesion to extracellular matrix proteins and expressed reduced levels of transcripts encoding fibronectin, integrins, endothelin B receptor, angiopoietin 2, and delta-like ligand 4 (Dll4). Together, these data identify unique cell-autonomous functions for HIF-2α in vascular endothelial cells.
Protection from graft-versus-host disease by HIV-1 envelope protein gp120-mediated activation of human CD4+CD25+ regulatory T cells
Authors: Becker Christian , Taube Christian , Bopp Tobias , Becker Christoph , Michel Kai , Kubach Jan , Reuter Sebastian , Dehzad Nina , Neurath Markus F. , Reifenberg Kurt , Schneider Franz-Joseph , Schmitt Edgar , Jonuleit Helmut 
Published: May 2009

AbstractNaturally occurring CD4+CD25+ regulatory T cells (Tregs) represent a unique T-cell lineage that is endowed with the ability to actively suppress immune responses. Therefore, approaches to modulate Treg function in vivo could provide ways to enhance or reduce immune responses and lead to novel therapies. Here we show that the CD4 binding human immunodeficiency virus-1 envelope glycoprotein gp120 is a useful and potent tool for functional activation of human Tregs in vitro and in vivo. Gp120 activates human Tregs by binding and signaling through CD4. Upon stimulation with gp120, human Tregs accumulate cyclic adenosine monophosphate (cAMP) in their cytosol. Inhibition of endogeneous cAMP synthesis prevents gp120-mediated Treg activation. Employing a xenogeneic graft versus host disease model that has been shown to be applicable for the functional analysis of human Tregs in vivo, we further show that a single dose of gp120 is sufficient to prevent lethal graft versus host disease and that the tolerizing effect of gp120 is strictly dependent on the presence of human Tregs and their up-regulation of cAMP upon gp120-mediated activation. Our findings demonstrate that stimulation via the CD4 receptor represents a T-cell receptor–independent Treg activating pathway with potential to induce immunologic tolerance in vivo.
Both systemic and local application of Granulocyte-colony stimulating factor (G-CSF) is neuroprotective after retinal ganglion cell axotomy
Authors: Frank Tobias , Schlachetzki Johannes CM , Göricke Bettina , Meuer Katrin , Rohde Gundula , Dietz Gunnar PH , Bähr Mathias , Schneider Armin , Weishaupt Jochen H 
Published: May 2009

Abstract

Background
The hematopoietic Granulocyte-Colony Stimulating Factor (G-CSF) plays a crucial role in controlling the number of neutrophil progenitor cells. Its function is mediated via the G-CSF receptor, which was recently found to be expressed also in the central nervous system. In addition, G-CSF provided neuroprotection in models of neuronal cell death. Here we used the retinal ganglion cell (RGC) axotomy model to compare effects of local and systemic application of neuroprotective molecules.

Results
We found that the G-CSF receptor is robustly expressed by RGCs in vivo and in vitro. We thus evaluated G-CSF as a neuroprotectant for RGCs and found a dose-dependent neuroprotective effect of G-CSF on axotomized RGCs when given subcutaneously. As stem stell mobilization had previously been discussed as a possible contributor to the neuroprotective effects of G-CSF, we compared the local treatment of RGCs by injection of G-CSF into the vitreous body with systemic delivery by subcutaneous application. Both routes of application reduced retinal ganglion cell death to a comparable extent. Moreover, G-CSF enhanced the survival of immunopurified RGCs in vitro.

Conclusion
We thus show that G-CSF neuroprotection is at least partially independent of potential systemic effects and provide further evidence that the clinically applicable G-CSF could become a treatment option for both neurodegenerative diseases and glaucoma.
The diamidine DB75 targets the nucleus of Plasmodium falciparum
Authors: Purfield Anne E , Tidwell Richard R , Meshnick Steven R 
Published: May 2009

Abstract

Background
DB289, [2,5-bis(4-amidinophenyl)furan bis-O-methylamidoxime], is a broad spectrum anti-parasitic compound which has been shown to be effective against malaria in recent clinical trials. DB75, [2,5-bis(4-amidinophenyl)furan], is the active metabolite of this drug. The objective of this study was to determine the mechanism of action of DB75 in Plasmodium falciparum.

Methods
Live parasites were observed by confocal microscopy after treatment with organelle specific dyes and DB75, an inherently fluorescent compound. Parasites were exposed to DB75 and assessed for growth and morphological changes over time using blood smears and light microscopy. Also, to determine if DB75 affects gene transcription, real time PCR was used to monitor transcript levels over time for six developmentally expressed genes, including trophozoite antigen R45-like (PFD1175w), lactate dehydrogenase (PF13_0141), DNA primase (PFI0530c), isocitrate dehydrogenase (PF13_0242), merozoite surface protein-1 (PFI1475w), and merozoite surface protein-7 (PF13_0197).

Results
The results show that DB75 localizes in the parasite nucleus but not in other organelles. Once rings are exposed, parasites mature to the trophozoite stage and stall. No stage-dependent or gene-specific inhibition of transcription was seen. However, DB75 delayed peak transcription of trophozoite-stage genes.

Conclusion
Taken together, DB75 appears to concentrate in the nucleus and delay parasite maturation.
Ovarian serous adenocarcinoma identified during IVF: diagnostic approach, surgical management, and reproductive outcome
Authors: Walsh David J , Sills Eric Scott , Shkrobot Lyuda V , Gleeson Noreen C , Sheppard Mary N , Walsh Anthony PH 
Published: May 2009

Abstract

Background
To present a diagnostic evaluation and treatment strategy for serous adenocarcinoma of the ovary discovered during an in vitro fertilisation (IVF) sequence, and report on reproductive outcome after tumour resection and embryo transfer.

Case presentation
Cycle monitoring in IVF identified an abnormal ovarian lesion which was subjected to ultrasound-guided needle aspiration. Cytology suggested malignancy, and unilateral oophorectomy was performed after formal staging. After surgery, the patient underwent an anonymous donor oocyte IVF cycle which established a viable twin intrauterine pregnancy. No recurrence of cancer has been detected in the >72 month follow-up interval; mother and twin daughters continue to do well.

Conclusion
Suspicious adnexal structures noted during controlled ovarian hyperstimulation for IVF warrant assessment, and this report confirms the role of aspiration cytology in such cases. If uterine conservation is possible, successful livebirth can be achieved from IVF if donor oocyes are utilised, as described here.