bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transcription of Subgenomic mRNA of Hepatitis Delta Virus Requires a Modified Hepatitis Delta Antigen That Is Distinct from Antigenomic RNA Synthesis
Authors: Tseng Chung-Hsin , Jeng King-Song , Lai Michael M. C. 
Published: July 2008

ABSTRACT
Hepatitis delta virus (HDV) contains a viroid-like, 1.7-kb circular RNA genome, which replicates via a double-rolling-circle model. However, the exact mechanism involved in HDV genome RNA replication and subgenomic mRNA transcription is still unclear. Our previous studies have shown that the replications of genomic and antigenomic HDV RNA strands have different sensitivities to α-amanitin and are associated with different nuclear bodies, suggesting that these two strands are synthesized in different transcription machineries in the cells. In this study, we developed a unique quantitative reverse transcription-PCR (qRT-PCR) procedure for detection of various HDV RNA species from an RNA transfection system. Using this qRT-PCR procedure and a series of HDV mutants, we demonstrated that Arg-13 methylation, Lys-72 acetylation, and Ser-177 phosphorylation of small hepatitis delta antigen (S-HDAg) are important for HDV mRNA transcription. In addition, these three S-HDAg modifications are dispensable for antigenomic RNA synthesis but are required for genomic RNA synthesis. Furthermore, the three RNA species had different sensitivities to acetylation and deacetylation inhibitors, showing that the metabolic requirements for the synthesis of HDV antigenomic RNA are different from those for the synthesis of genomic RNA and mRNA. In sum, our data support the hypothesis that the cellular machinery involved in the synthesis of HDV antigenomic RNA is different from that of genomic RNA synthesis and mRNA transcription, even though the antigenomic RNA and the mRNA are made from the same RNA template. We propose that acetylation and deacetylation of HDAg may provide a molecular switch for the synthesis of the different HDV RNA species.
A Mobile Functional Region of Kaposi's Sarcoma-Associated Herpesvirus ORF50 Protein Independently Regulates DNA Binding and Protein Abundance
Authors: Chang Pey-Jium , Shedd Duane , Miller George 
Published: July 2008

ABSTRACT

The protein encoded by open reading frame 50 (ORF50) of Kaposi's sarcoma-associated herpesvirus (KSHV) functions as a transcriptional activator and in lytic viral DNA replication to mediate the switch from latent viral infection to the lytic phase. Here we identify regulatory regions of ORF50 protein that independently control DNA binding and abundance of the protein. One region contains a DNA-binding inhibitory sequence (DBIS) located between amino acids (aa) 490 and 535 of ORF50. A cluster of basic amino acids in this sequence is important in inhibiting DNA binding. The DBIS can function at the N or C terminus or internally in the ORF50 protein. Since the DBIS is functional in ORF50 protein purified from
Escherichia coli
, it is likely to work through an intramolecular mechanism. The second regulatory region, a protein abundance regulatory signal (PARS), consists of two components. Component I of the PARS overlaps the DBIS but can be differentiated from the DBIS by specific substitution of basic amino acid residues. Component II of PARS is located between aa 590 and 650. Mutation or deletion of either component results in abundant expression of ORF50 protein. When the two-component PARS was fused to a heterologous protein, Glutathione
S
-transferase, the fusion protein was unstable. Mutations in the DBIS or PARS impair the capacity of ORF50 to activate direct and indirect target viral promoters. Since these overlapping regulatory motifs are located in the C-terminal transactivation domain, they are likely to be important in controlling many actions of ORF50 protein.
Aichi Virus 2A Protein Is Involved in Viral RNA Replication
Authors: Sasaki Jun , Taniguchi Koki 
Published: July 2008

ABSTRACT
The Aichi virus 2A protein is not a protease, unlike many other picornavirus 2A proteins, and it is related to a cellular protein, H-rev107. Here, we examined the replication properties of two 2A mutants in Vero cells and a cell-free translation/replication system. In one mutant, amino acids 36 to 126 were replaced with an unrelated amino acid sequence. In the other mutant, the NC motif conserved in the H-rev107 family of proteins was changed to alanine residues. The two mutations abolished virus replication in cells. The mutations affected both negative- and positive-strand synthesis, the defect in positive-strand synthesis being more severe than that in negative-strand synthesis.
Solid-Liquid Equilibrium in the Systems with an Ionic Liquid
Authors: Sedláková Zuzana , Sauton Hélène , Hynek Vladimír , Malijevská Ivona 
Published: July 2008

An active interest in ionic liquids has grown over the last years. This relatively new class of solvents appears to be potentially useful as a "greener" alternative to volatile organic compounds. This work was aimed at studying the effect of addition of the ionic liquid 1-butyl-3-methylimidazolium chloride to two systems (acetic acid (1)-formamide (2) and propionic acid (1)-formamide (2)) on formation of a compound in the solid phase. In previous work, the presence of a solid compound with a formula (CH3COOH)2·HCONH2 was investigated in the binary system acetic acid (1)-formamide (2) and a stable solid compound with a different formula CH3CH2COOH·(HCONH2)2 was found in the binary system propionic acid (1)-formamide (2). In both cases the compound formation is attributed to a strong cross-association (O···H···N). Solid-liquid equilibrium of the systems measured in this work was determined from time-temperature warming curves. In both measured ternary systems with a small addition of the ionic liquid 1-butyl-3-methylimidazolium chloride (i.e. the systems acetic acid (1)-formamide (2)-1-butyl-3-methylimidazolium chloride (3) and propionic acid (1)-formamide (2)-1-butyl-3-methylimidazolium chloride (3)) the above mentioned stable solid compounds are formed and the corresponding melting temperature of these compounds decreased. Dissociation parameters were modelled thermodynamically for solid adducts.
Dispersal in a sterile lichen-forming fungus,Thamnolia subuliformis(Ascomycotina: Icmadophilaceae)This paper is one of a selection of papers published in the Special Issue on Systematics Research.
Authors: Cassie David M. , Piercey-Normore Michele D. 
Published: July 2008

Thamnolia subuliformis (Ehrh.) Culb. is a sterile lichen-forming ascomycete with no known sexual or vegetative reproductive structures except fragments of thallus branches. The open tundra in northern Manitoba contains fragments of T. subuliformis randomly scattered over the landscape, giving the appearance that dispersal is common. This may provide a misleading impression of gene flow, but similar fragmentation is seen in seven other locally occurring species of lichen-forming fungi. The primary objective of this study was to examine the population structure of T. subuliformis using four multilocus markers (interspersed simple sequence repeats; ISSR) and a single locus marker (the presence/absence of a group I intron in the nuclear 18S rDNA locus). Significant population subdivision is reported for two different classifications of what constitutes a population. Thallus fragments of T. subuliformis may be intact and slow growing, having accumulated tissue over a long period of time, with low levels of gene flow occurring in localized areas. The presence of the group 1 intron in localized transects may suggest either that the intron was introduced recently and has not had sufficient time to disperse among populations, or that it has been lost in other locations.
The Power of Monitoring Stations and a CO2 Fertilization Effect: Evidence from Causal Relationships between NDVI and Carbon Dioxide
Authors: Kaufmann R. K. , Paletta L. F. , Tian H. Q. , Myneni R. B. , D’Arrigo R. D. 
Published: July 2008

Abstract
Two hypotheses are tested: 1) monitoring stations (e.g., Mauna Loa) are not able to measure changes in atmospheric concentrations of CO2 that are generated by changes in terrestrial vegetation at distant locations; 2) changes in the atmospheric concentration of carbon dioxide do not affect terrestrial vegetation at large scales under conditions that now exist in situ, by estimating statistical models of the relationship between satellite measurements of the normalized difference vegetation index (NDVI) and the atmospheric concentration of carbon dioxide measured at Mauna Loa and Point Barrow. To go beyond simple correlations, the notion of Granger causality is used. Results indicate that the authors are able to identify locations where and months when disturbances to the terrestrial biota “Granger cause” atmospheric CO2. The authors are also able to identify locations where and months when disturbances to the atmospheric concentration of carbon dioxide generate changes in NDVI. Together, these results provide large-scale support for a CO2 fertilization effect and an independent empirical basis on which observations at monitoring stations can be used to test hypotheses and validate models regarding effect of the terrestrial biota on atmospheric concentrations of carbon dioxide.
The Effect of Local Anesthetics Administered via Pain Pump on Chondrocyte Viability
Authors: Dragoo Jason L. , Korotkova Tatiana , Kanwar Raj , Wood Billy 
Published: July 2008

Background Chondrolysis initiated by postoperative, intra-articular pain pumps has recently been described by multiple institutions. Purpose To evaluate the in vitro chondrotoxicity of anesthetic formulations commonly used in pain pumps. Study Design Controlled laboratory study. Methods Freshly isolated human articular chondrocytes were cultured for 24-, 48-, and 72-hour trials in a custom bioreactor that mimics the metabolism of synovial fluid. Chondrocytes were perfused in Dulbecco's Modified Eagle's Medium 10% fetal bovine serum and one of the following medications: 1 % lidocaine, 1 % lidocaine with epinephrine, 0.25% bupivacaine, 0.25% bupivacaine with epinephrine, 0.5% bupivacaine, or 0.5% bupivacaine with epinephrine. Static and perfusion cultures with growth media were used as controls. All experiments were run in duplicate. Live/dead staining was performed, and the ratio of dead: Live cells was assessed by fluorescent microscopy and histomorphometry. Results Significantly more chondrocyte necrosis was found in all cultures with medications containing epinephrine ( P < .05) at all time points. Similar necrosis rates were exhibited in 0.25% and 0.5% bupivacaine compared with controls at 24 and 48 hours. However, 0.5% bupivacaine produced significantly more cell death at 72 hours. Similar necrosis rates were exhibited with 1 % lidocaine compared to controls at 24 hours. Conclusion In this in vitro model, 0.25% and 0.5% bupivacaine caused minimal chondrocyte necrosis when used in pain pumps for a maximum of 48 hours. All anesthetics containing epinephrine (pH  4) were chondrotoxic and cannot be advocated for pain pump use. The use of 0.5% bupivacaine for greater than 48 hours is not recommended. Clinical Relevance The results of this study may help improve the safety of intra-articular pain pump use by examining the effects of local anesthetics on chondrocyte viability.
Should SDMT substitute for PASAT in MSFC? A 5-year longitudinal study
Authors: Brochet B , Deloire MSA , Bonnet M , Salort-Campana E , Ouallet JC , Petry KG , Dousset V 
Published: July 2008

Background The multiple sclerosis functional composite (MSFC) includes the Paced Auditory Serial Addition test (PASAT) as a measure of cognition. Objectives and methods We compared the MSFC incorporating the Symbol Digit Modalities test (SDMT) (MSFC [sdmt]) to the usually applied MSFC (MSFC [pasat]) in a sample of 46 ptients with relapsing–remitting MS who were followed over a five-year period. Magnetic resonance imaging was performed at baseline. Results The Expanded Disability Status scale (EDSS) deteriorated significantly over 5 years ( P < 0.01), but MSFC scores remained stable. MSFC [sdmt] correlated with EDSS at all time points of evaluation, but MSFC [pasat] correlated with EDSS only at baseline, 1, and 5 years. The 5-year EDSS correlated significantly with baseline MSFC [sdmt] and MSFC [pasat] but did not correlate after adjustment for baseline EDSS. No significant correlation was found at baseline between MSFC and imaging parameters (lesion load, brain parenchymal fraction [BPF], ventricular fraction, mean magnetization transfer ratio of lesions and normal-appearing brain tissue), but baseline BPF correlated significantly with changes of SDMT z score ( P = 0.0003), MSFC [pasat] ( P = 0.006), and MSFC [sdmt] ( P = 0.0002) over 5 years. Conclusion We propose not to substitute PASAT by SDMT in the MSFC but to consider SDMT as a complementary useful approach to evaluate overall MS disease.
Multiple sclerosis: reduced proportion of circulating plasmacytoid dendritic cells expressing BDCA-2 and BDCA-4 and reduced production of IL-6 and IL-10 in response to herpes simplex virus type 1
Authors: Sanna A , Huang YM , Arru G , Fois ML , Link H , Rosati G , Sotgiu S 
Published: July 2008

Objective We hypothesized that autoaggressive immune responses observed in multiple sclerosis (MS) could be associated with an imbalance in proportion of immune cell subsets and in cytokine production in response to infection, including viruses. Methods We collected blood mononuclear cells (MNC) from 23 patients with MS and 23 sex- and age-matched healthy controls (HC) from the island of Sardinia, Italy, where the prevalence of MS is extraordinarily high. Using flow cytometry, we studied MNC for expression of blood dendritic cell antigens (BDCA)-2 and BDCA-4 surface markers reflecting the proportion of plasmacytoid dendritic cells (pDC) that produce type I interferons (IFNs) after virus challenge and promote Th2/anti-inflammtory cytokine production. In parallel, pro-inflammatory (interleukin [IL]-2, IL-12, IFN-γ), anti-inflammatory (IL-4, IL-10), and immuno-regulatory/pleiotropic cytokines (type I IFNs including IFN-α and β, IL-6) were measured before and after an in vitro exposure to herpes simplex virus type 1 (HSV-1). Results The subset of lineage negative (lin−), BDCA-2+ cells was lower in patients with MS compared with HC (0.08 ± 0.02% vs 0.24 ± 0.02%; P < 0.001). A similar pattern was observed for lin−BDCA-4+ cells (0.08 ± 0.02% vs 0.17% ± 0.03; P < 0.01). Spontaneous productions of IL-6 (45 ± 10 pg/mL vs 140 ± 26 pg/mL; P < 0.01) and IL-10 (17 ± 0.4 pg/mL vs 21 ± 1 pg/mL; P < 0.05) by MNC were lower in patients with MS compared with HC. Spontaneous production of IL-6 (6.5 ± 0.15 pg/mL vs 21 ± 5 pg/mL; P < 0.01 and IL-10 (11 ± 1 pg/mL vs 14 ± 3 pg/mL; P < 0.05) by pDC was also lower in patients with MS compared with HC. Exposure of MNC to HSV-1 showed, in both patients with MS and HC, increased production of IFN-α, IL-6, and IL-10 but decreased production of IL-4. In response to HSV-1 exposure, productions of IL-6 (165 ± 28 pg/mL vs 325 ± 35 pg/mL; P < 0.01) and IL-10 (27 ± 3 vs 33 ± 3 P < 0.05) by MNC as well as by pDC (IL-6: 28 ± 7 vs 39 ± 12 P < 0.05; IL-10: 14 ± 1 vs 16 ± 3 P < 0.05) were lower in patients with MS compared with HC. Conclusion The results implicate a new evidence for altered immune cells and reduced immune responses in response to viral challenge in MS.
Peroxisome proliferator-activated receptor-α reduces inflammation and vascular leakage in a murine model of acute lung injury
Authors: Schaefer M. B. , Pose A. , Ott J. , Hecker M. , Behnk A. , Schulz R. , Weissmann N. , Günther A. , Seeger W. , Mayer K. 
Published: July 2008

Acute lung injury (ALI) still represents a major cause of morbidity and mortality in intensive care units. Beneficial effects have been described after activation of the peroxisome proliferator-activated receptor (PPAR)-α by fibrates such as WY 14,643 (WY) in inflammatory models. In the present study, the impact of WY was investigated in a model of endotoxin (lipopolysaccharide; LPS)-induced ALI in mice.Intratracheal LPS challenge dose-dependently resulted in leukocyte invasion, protein leakage and release of tumour necrosis factor-α as well as macrophage inflammatory protein-2, prostaglandin E2and thromboxane B2into the alveolar space after 8 and 24 h. Lung ventilator compliance was reduced at both time-points. In isolated perfused mouse lungs, platelet-activating factor (PAF) induced an acute increase in pulmonary artery pressure (Ppa) and in capillary filtration coefficient (Kfc). WY significantly improved all features of ALIin vivoand blunted the increase inKfcin isolated perfused mice lungs. In mice with genetic deletion of PPAR-α, all characteristics of ALI,Ppa, andKfcwere not significantly different from wild-type mice but WY failed to improve ALI and PAF-induced increase inKfc.Activation of peroxisome proliferator-activated receptor-α by WY 14,643 reduced acute lung injury and vascular leakage. Fibrates may possess beneficial effects in acute pulmonary diseases beyond their lipid-lowering capability.
The epidermal growth factor receptor mediates allergic airway remodelling in the rat
Authors: Tamaoka M. , Hassan M. , McGovern T. , Ramos-Barbón D. , Jo T. , Yoshizawa Y. , Tolloczko B. , Hamid Q. , Martin J. G. 
Published: July 2008

The chronicity of bronchial asthma is attributed to persistent airway inflammation and to a variety of structural changes, or remodelling, that includes smooth muscle and goblet cell hyperplasia.To investigate the mechanisms of airway remodelling, the current authors used an established allergen (ovalbumin; OVA)-driven rodent model (the Brown Norway rat).Brown Norway rats were sensitised to OVA and challenged three times at 5-day intervals to evoke airway remodelling. The effects of an epidermal growth factor (EGF) receptor inhibitor, AG1478, and a cysteinyl leukotriene-1 receptor antagonist, montelukast, on epithelial and airway smooth muscle (ASM) cell proliferationin vivoin response to repeated OVA challenge were tested. Three challenges with leukotriene (LT)D4were given, to examine their effects on remodelling with and without AG1478 pretreatment.OVA challenges caused ASM hyperplasia, with an increase in mass, epithelial cell proliferation and goblet cell proliferation. AG1478 prevented the changes, as did montelukast. Multiple OVA challenges increased heparin-binding EGF-like growth factor but not EGF expression by airway epithelium. LTD4reproduced the changes in remodelling induced by OVA and this was blocked by AG1478.Allergen-induced airway epithelial and airway smooth muscle remodelling is mediated by cysteinyl leukotrienesviathe cysteinyl leukotriene-1 receptor with downstream effects on the epidermal growth factor receptor axis.
RNA interference for CFTR attenuates lung fluid absorption at birth in rats
Authors: Li Tianbo , Koshy Shyny , Folkesson Hans G 
Published: July 2008

Abstract

Background
Small interfering RNA (siRNA) against αENaC (α-subunit of the epithelial Na channel) and CFTR (cystic fibrosis transmembrane conductance regulator) was used to explore ENaC and CTFR function in newborn rat lungs.

Methods
Twenty-four hours after trans-thoracic intrapulmonary (ttip) injection of siRNA-generating plasmid DNA (pSi-0, pSi-4, or pSi-C2), we measured CFTR and ENaC expression, extravascular lung water, and mortality.

Results
αENaC and CFTR mRNA and protein decreased by ~80% and ~85%, respectively, following αENaC and CFTR silencing. Extravascular lung water and mortality increased after αENaC and CFTR-silencing. In pSi-C2-transfected isolated DLE cells there were attenuated CFTR mRNA and protein. In pSi-4-transfected DLE cells αENaC mRNA and protein were both reduced. Interestingly, CFTR-silencing also reduced αENaC mRNA and protein. αENaC silencing, on the other hand, only slightly reduced CFTR mRNA and protein.

Conclusion
Thus, ENaC and CFTR are both involved in the fluid secretion to absorption conversion around at birth.
New steroidal aromatase inhibitors: Suppression of estrogen-dependent breast cancer cell proliferation and induction of cell death
Authors: Cepa Margarida , Correia-da-Silva Georgina , da Silva Elisiário J Tavares , Roleira Fernanda MF , Borges Margarida , Teixeira Natércia A 
Published: July 2008

Abstract

Background
Aromatase, the cytochrome P-450 enzyme (CYP19) responsible for estrogen biosynthesis, is an important target for the treatment of estrogen-dependent breast cancer. In fact, the use of synthetic aromatase inhibitors (AI), which induce suppression of estrogen synthesis, has shown to be an effective alternative to the classical tamoxifen for the treatment of postmenopausal patients with ER-positive breast cancer. New AIs obtained, in our laboratory, by modification of the A and D-rings of the natural substrate of aromatase, compounds 3a and 4a, showed previously to efficiently suppress aromatase activity in placental microsomes. In the present study we have investigated the effects of these compounds on cell proliferation, cell cycle progression and induction of cell death using the estrogen-dependent human breast cancer cell line stably transfected with the aromatase gene, MCF-7 aro cells.

Results
The new steroids inhibit hormone-dependent proliferation of MCF-7aro cells in a time and dose-dependent manner, causing cell cycle arrest in G0/G1 phase and inducing cell death with features of apoptosis and autophagic cell death.

Conclusion
Our in vitro studies showed that the two steroidal AIs, 3a and 4a, are potent inhibitors of breast cancer cell proliferation. Moreover, it was also shown that the antiproliferative effects of these two steroids on MCF-7aro cells are mediated by disrupting cell cycle progression, through cell cycle arrest in G0/G1 phase and induction of cell death, being the dominant mechanism autophagic cell death. Our results are important for the elucidation of the cellular effects of steroidal AIs on breast cancer.
Conjugated linoleic acid induces apoptosis through estrogen receptor alpha in human breast tissue
Authors: Wang Li-Shu , Huang Yi-Wen , Liu Suling , Yan Pearlly , Lin Young C 
Published: July 2008

AbstractBackgroundConjugated linoleic acid (CLA), a naturally occurring fatty acid found in ruminant products such as milk and beef, has been shown to possess anti-cancer activities inin vivoanimal models andin vitrocell culture systems. In human breast cancer, the overall duration of estrogen exposure is the most important risk factor for developing estrogen-responsive breast cancer. Accordingly, it has been suggested that estrogen exposure reduces apoptosis through the up-regulation of the anti-apoptosis protein, Bcl-2. Bcl-2, an anti-apoptotic protein, regulates apoptosis and plays a crucial role in the development and growth regulation of normal and cancerous cells. Our research interest is to examine the effects of CLA on the induction of apoptosis in human breast tissues.MethodsThe localization of Bcl-2 in both normal and cancerous human breast tissues was determined by immunohistochemical staining and the Bcl-2 protein expression was tested by western blot analysis. Co-culture of epithelial cells and stromal cells was carried out in the presence or absence of CLA to evaluate apoptosis in the context of a cell-cell interaction.ResultsThe results showed that both normal and cancerous breast tissues were positive for Bcl-2 staining, which was higher overall in mammary ducts but very low in the surrounding stromal compartment. Interestingly, by quantifying the western blot data, basal Bcl-2 protein levels were higher in normal breast epithelial cells than in cancerous epithelial cells. Furthermore, treatment with 17β-estradiol (E2) stimulated growth and up-regulated Bcl-2 expression in estrogen responsive breast epithelial cells; however, these carcinogenic effects were diminished by either CLA or 4-Hydroxytamoxifen (Tam) and were suppressed further by the combination of CLA and Tam. In both one cell type cultured and co-culture systems, CLA induced cell apoptosis in ERα transfected MDA-MB-231 cells but not in the wild type MDA-MB-231 cells.ConclusionThese data, therefore, demonstrate that ERα plays important roles in CLA induced apoptosis in human breast tissues.