bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hsp22 (HspB8/H11) knockdown induces sam68 expression and stimulates proliferation of glioblastoma cells
Authors: Modem Suhasini , Chinnakannu Kannagi , Bai Uma , Reddy G. Prem‐Veer , Reddy Thipparthi R. 
Published: June 2011

AbstractSam68 (Src‐associated protein in mitosis 68 kDa) is a multifunctional protein, known to govern cellular signal transduction, transcription, RNA metabolism, proliferation, apoptosis, and HIV‐1 replication. Although intrinsic mechanisms that modulate Sam68 function are beginning to emerge, the regulatory events contributing to its expression remain elusive. We previously reported that heat shock protein‐22 (Hsp22) antagonizes Sam68 function in rev‐response element (RRE)‐mediated gene expression. We now demonstrate that Sam68 levels correlate inversely with Hsp22 in a variety of cells, including U87, Jurkat, 293T, and U‐937. In U87 glioblastoma cells, which contained high levels of Hsp22 than other cell lines tested, Hsp22 knockdown dramatically increased both Sam68 mRNA and protein, altered cellular morphology, and enhanced cell proliferation. This heightened proliferation was associated with a sharp decrease in G0/G1 and a corresponding increase in S and G2/M phases in exponentially growing cultures. The increased S phase population in turn correlated with enhanced expression of cell cycle regulatory proteins such as cyclin E, cyclin A, ribonucleotide reductase (RNR), and proliferating cell nuclear antigen (PCNA), which are required for the transition of cells from G1 to S phase. Collectively, our results demonstrate for the first time that Hsp22 regulates Sam68 expression and the ratio of Sam68 to Hsp22 may determine the proliferative potential of glioblastoma cells. J. Cell. Physiol. 226: 2747–2751, 2011. © 2011 Wiley‐Liss, Inc.
Inhibition of human methionine adenosyltransferase 1A transcription by coding region methylation
Authors: Tomasi Maria Lauda , Li Tony W.H. , Li Mei , Mato José M. , Lu Shelly C. 
Published: June 2011

AbstractTwo genes (MAT1A and MAT2A) encode for the essential enzyme methionine adenosyltransferase (MAT). MAT1A is silenced in hepatocellular carcinoma (HCC), and absence of MAT1A leads to spontaneous development of HCC in mice. Previous report correlated promoter methylation to silencing of MAT1A but definitive proof was lacking. Here we investigated the role of methylation in regulating MAT1A expression. There are three MspI/HpaII sites from −1,913 to +160 of the human MAT1A gene (numbered relative to the translational start site) at position −977, +10, and +88. Bisulfite treatment and DNA sequencing, and Southern blot analysis showed that methylation at +10 and +88, but not −977, correlated with lack of MAT1A expression. MAT1A promoter construct methylated at −977, +10 or +88 position has 0.7‐fold, 3‐fold, and 1.6‐fold lower promoter activity, respectively. Methylation at −977 and +10 did not inhibit the promoter more than methylation at +10 alone; while methylation at +10 and +88 reduced promoter activity by 60%. Mutation of +10 and +88 sites also resulted in 40% reduction of promoter activity. Reactivation of MAT1A correlated with demethylation of +10 and +88. In vitro transcription assay showed that methylation or mutation of +10 and +88 sites reduced transcription. In conclusion, our data support the novel finding that methylation of the MAT1A coding region can inhibit gene transcription. This represents a key mechanism for decreased MAT1A expression in HCC and a target for therapy. To our knowledge, this is the first example of coding region methylation inhibiting transcription of a mammalian gene. J. Cell. Physiol. 227: 1583–1591, 2012. © 2011 Wiley Periodicals, Inc.
Molecular characterization of myosin phosphatase in endothelium
Authors: Kim Kyung‐mi , Csortos Csilla , Czikora Istvan , Fulton David , Umapathy Nagavedi S. , Olah Gabor , Verin Alexander D. 
Published: June 2011

AbstractThe phosphorylation status of myosin light chain (MLC) is regulated by both MLC kinases and type 1 Ser/Thr phosphatase (PPase 1), MLC phosphatase (MLCP) activities. The activity of the catalytic subunit of MLCP (CS1β) towards myosin depends on its associated regulatory subunit, namely myosin PPase targeting subunit 1 (MYPT1). Our previously published data strongly suggested the involvement of MLCP in endothelial cell (EC) barrier regulation. In this study, our new data demonstrate that inhibition of MLCP by either CS1β or MYPT1 siRNA‐based depletion results in significant attenuation of purine nucleotide (ATP and adenosine)‐induced EC barrier enhancement. Consistent with the data, thrombin‐induced EC F‐actin stress fiber formation and permeability increase were attenuated by the ectopic expression of constitutively active (C/A) MYPT1. The data demonstrated for the first time direct involvement of MLCP in EC barrier enhancement/protection. Cloning of MYPT1 in human pulmonary artery EC (HPAEC) revealed the presence of two MYPT1 isoforms, long and variant 2 (V2) lacking 56 amino acids from 553 to 609 of human MYPT1 long, which were previously identified in HeLa and HEK 293 cells. Our data demonstrated that in Cos‐7 cells ectopically expressed EC MYPT1 isoforms co‐immunoprecipitated with intact CS1β suggesting the importance of PPase 1 activity for the formation of functional complex of MYPT1/CS1β. Interestingly, MYPT1 V2 shows decreased binding affinity compared to MYPT1 long for radixin (novel MLCP substrate and a member of ERM family proteins). These results suggest functional difference between EC MYPT1 isoforms in the regulation of MLCP activity and cytoskeleton. J. Cell. Physiol. 227: 1701–1708, 2012. © 2011 Wiley Periodicals, Inc.
Microalgae biodiesel via in situ methanolysis
Authors: Carvalho Júnior Rui M. , Vargas José V. C. , Ramos Luiz P. , Marino Cláudia E. B. , Torres Jonas C. L. 
Published: June 2011

AbstractBACKGROUND: Microalgae have recently been considered a potential feedstock for biodiesel production, since they do not compete with agricultural land, unlike oil crops. However, the production processes must be energetically and economically viable. Therefore, an in situ methanolysis process is proposed for biodiesel production directly from microalgae biomass, to avoid the need for the separation and extraction steps.RESULTS: Biodiesel was obtained using methanol as the methylation reactant for the transesterification reaction and hydrochloric acid as the catalyst precursor, at 80 °C for 2 h of reaction. A mass return of 23.07 ± 2.76% (m/m) was obtained. Spectrometry in the infrared region showed that the product had equivalent bands of axial deformation of CO, CO and CH, i.e. an ester. Tests showed the chromatographic profile of fatty acids in the sample. A process energetic efficiency value of 1.17 was obtained for microalgae derived biodiesel, which is higher than from soybean and sunflower, reportedly 1.06 and 1.12.CONCLUSIONS: Industrial sustainability results from low energetic, economic and environmental losses. The microalgae in situ methanolysis process showed greater fuel available energy than energy consumption, therefore is energetically sustainable. Economic and environmental issues should still be addressed. Copyright © 2011 Society of Chemical Industry
Assessing the use of xylanase and laccases in biobleaching stages of a TCF sequence for flax pulp
Authors: Fillat Amanda , Roncero M. Blanca , Vidal Teresa 
Published: June 2011

AbstractBACKGROUND: In this study, two different laccases were used in combination with various mediators as biobleaching agents in a TCF sequence for flax fibre and pulp. Thus, non‐commercial laccase from Pycnoporus cinnabarinus (PcL) was used with the synthetic mediator violuric acid (VA) or the natural mediator syringaldehyde (SA), and commercial laccase from Myceliophthora thermophila (MtL) was used with the natural mediator methyl syringate (MS). Each laccase–mediator treatment was used in the following TCF bleaching sequence: LQPo (Q denoting a chelating stage and Po a pressurized alkaline peroxide treatment). Also, a xylanase pretreatment was carried out for first time here to assess its effect on flax fibre. Pulp (kappa number, viscosity and brightness) and effluent properties (COD, colour, residual activity and toxicity) were determined after each bleaching stage. The hexenuronic acid (HexA) content of the pulp was also determined to assess its integrity.RESULTS: The best L stage was PcL + VA, which provided a final brightness and kappa number of 81% ISO and 1.3, respectively. Using a xylanase pretreatment was found to efficiently remove HexA and enhance delignification by laccase (final kappa number 0.7).CONCLUSIONS: These results warrant upscaling any of these biobleaching sequences for flax pulp as they provide environmentally sustainable flax fibre with a high cellulose content and brightness above 80% ISO. Copyright © 2011 Society of Chemical Industry
Topography of four different endodontic rotary systems, before and after being used for the 12th time
Authors: Yamazaki‐Arasaki Andréa , Cabrales Ricardo , Santos Marcelo Dos , Kleine Brígida , Prokopowitsch Igor 
Published: June 2011

AbstractRoot canal preparation may damage NiTi instruments resulting in wear and deformation. The aim of this study was to make a comparative evaluation of the surface topography of the cervical third of four different rotary systems, before and after being used twelve times, in 1.440 resin blocks with simulated root canals with standardized 45° curvatures, and analyzed by atomic force microscopy &&num;150; AFM. The blocks were divided into four groups and prepared according to the manufacturers recommendations: Group 1 ‐ K3®; Group 2 ‐ Protaper Universal®; Group 3 ‐ Twisted Files® and Group 4 ‐ Biorace®. After each preparation, the instruments were washed and autoclaved. A total of 240 instruments were selected, being 30 new instruments and 30 after having been used for the 12th time, from each group. These instruments were analyzed by AFM and for quantitative evaluation, the mean RMS (Root mean square) values of the cervical third of the specimens from the four groups were used. The result showed that all the rotary files used for the 12th time suffered wear with change in the topography of the cervical region of the active portion of the file (ANOVA p < 0.01). Classifying the specimens in increasing order, from the least to the greatest wear suffered, Group 3 (2.8993 nm) presented the least wear, followed by Group 4 (12.2520 nm), Group 1 (36.0043 nm) and lastly, Group 2 (59.8750 nm) with the largest amount of cervical surface wear. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
Neurotrophin Trk receptors in the brain of a teleost fish, Nothobranchius furzeri
Authors: D'Angelo Livia , de Girolamo Paolo , Cellerino Alessandro , Tozzini Eva Terzibasi , Castaldo Luciana , Lucini Carla 
Published: June 2011

AbstractTrk neurotrophin receptors are transmembrane tyrosine kinase proteins known as TrkA, TrkB, and TrkC. TrkA is the high affinity receptor for nerve growth factor, TrkB is the one for both brain‐derived neurotrophic factor and neurotrophin‐4, and TrkC is the preferred receptor for neurotrophin‐3. In the adult mammalian brain, neurotrophins are important regulators of neuronal function and plasticity. This study is based on Nothobranchius furzeri, a teleost fish that is becoming an ideal candidate as animal model for aging studies because its life expectancy in captivity is of just 3 months. In adult N. furzeri, all three investigated neurotrophin Trk receptors were immunohistochemically detected in each brain region. TrkA positive neuronal perikarya were localized in the dorsal and ventral areas of the telencephalon and in the cortical nucleus; TrkB immunoreactivity was observed in neuronal perikarya of the dorsal and ventral areas of the telencephalon, the diffuse inferior lobe of the hypothalamus, and Purkinje cells; TrkC positive neuronal perikarya were detected in the most aboral region of the telencephalon, in the magnocellular preoptic nucleus and in few neurons dispersed in the hypothalamus. Numerous positive fibers were widely distributed throughout the brain. Radial glial cells lining the mesencephalic and rhombencephalic ventricles showed immunoreactivity to all three Trks. These findings suggest an involvement of neurotrophins in many aspects of biology of adult N. furzeri. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
Enhanced delivery of monomethoxypoly(ethylene glycol)‐poly(lactic‐co‐glycolic acid)‐poly l‐lysine nanoparticles loading platelet‐derived growth factor BB small interfering RNA by ultrasound and/or microbubbles to rat retinal pigment epithelium cells
Authors: Du Jing , Shi Qiu Sheng , Sun Ying , Liu Pei Feng , Zhu Ming Jie , Du Lian Fang , Duan You Rong 
Published: June 2011

AbstractBackgroundA novel small interfering RNA (siRNA) delivery method based on the combined use of nanoparticles (NPs) with ultrasound (US) and/or microbubbles (MBs) was introduced in the present study. We investigated the efficacy and safety of US and/or MBs‐enhanced delivery of monomethoxypoly(ethylene glycol)‐poly(lactic‐co‐glycolic acid)‐poly l‐lysine (mPEG‐PLGA‐PLL) NPs loading platelet‐derived growth factor BB (PDGF‐BB) siRNA to rat retinal pigment epithelium (RPE)‐J cells.MethodsThe effect of US and/or MBs on the delivery of NPs containing Cy3‐labeled siRNA was evaluated by fluorescence microscopy and flow cytometry. Potential toxicity of NPs and cell viability under different conditions of US and/or MBs were assessed by the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide method.ResultsThe results obtained showed that low intensity US or 15–20% MBs could increase the delivery efficiency of a lower concentration of mPEG‐PLGA‐PLL NPs loading siRNA to RPE‐J cells, whereas the combination of US with MBs under the optimal conditions for the enhancement of NPs delivery did not further increase the cellular uptake of NPs compared to either US or MBs alone (p = 0.072 and p = 0.488, respectively). Under the optimal condition for US‐enhanced NPs delivery, the enhanced PDGF‐BB gene silencing with a combination of US and NPs encapsulating siRNA resulted in a significant decrease of mRNA and protein expression levels compared to NPs alone.ConclusionsUS and/or MBs could be used safely to enhance the delivery of NPs loading siRNA to rat RPE‐J cells. A combination of the chemical (mPEG‐PLGA‐PLL NPs loading siRNA) and physical (US) approaches could more effectively downregulate the mRNA and protein expression of PDGF‐BB. Copyright © 2011 John Wiley & Sons, Ltd.
Structural identification of SAR‐943 metabolites generated by human liver microsomes in vitro using mass spectrometry in combination with analysis of fragmentation patterns
Authors: Strom Tobin , Shokati Touraj , Klawitter Jost , Klawitter Jelena , Hoffman Keith , Schiebel Hans‐Martin , Christians Uwe 
Published: June 2011

AbstractSAR‐943 (32‐deoxo rapamycin) is a proliferation signal inhibitor via interaction with the mammalian target of rapamycin (mTOR). Most importantly, SAR‐943 has improved chemical stability compared to rapamycin (sirolimus) and is currently under investigation as a drug coated on coronary stents. It was the goal of this study to identify the SAR‐943 metabolites generated after incubation with human liver microsomes using high‐resolution mass spectrometry (MS) and MS/iontrap (MSn) and comparison of fragmentation patterns of the metabolites with those of SAR‐943 and other known rapamycin derivatives. Our study showed that SAR‐943 is mainly hydroxylated and/or demethylated by human liver microsomes. The structures of the following metabolites were identified: O‐demethylated metabolites: 39‐O‐desmethyl, 16‐O‐desmethyl and 27‐O‐desmethyl SAR‐943; hydroxylated metabolites: hydroxy piperidine SAR‐943, 11‐hydroxy, 12‐hydroxy, 14‐hydroxy, 23‐hydroxy, 24‐hydroxy, 25‐hydroxy, 46‐hydroxy and 49‐hydroxy SAR‐943; didemethylated metabolites: 16,39‐O‐didesmethyl and 27,39‐O‐didesmethyl SAR‐943; demethylated‐hydroxylated metabolites: 39‐O‐desmethyl, 23‐ or 24‐hydroxy and 39‐O‐desmethyl, hydroxy piperidine SAR‐943 and dihydroxylated metabolites: 12‐,23‐ or 24‐dihydroxy SAR‐943. In addition, several other demethylated‐hydroxylated and dihydroxylated metabolites were detected. However, their exact structures could not be identified. Copyright © 2011 John Wiley & Sons, Ltd.
Low‐level persistence of human papillomavirus 16 DNA in a cohort of closely followed adolescent women
Authors: Weaver B. , Shew M. , Qadadri B. , Tu W. , Tong Y. , Denski C. , Fortenberry J.D. , Ermel A. , Brown D. 
Published: June 2011

AbstractMost human papillomavirus (HPV) infections in young women become undetectable by standard assays after a few months. It is possible that many HPV infections do not actually clear, but persist at very low levels for years, becoming detected again later in life. The purpose of this study is to describe HPV 16 clearance, reappearance, and low‐level persistence in a cohort of adolescent women. Adolescent women (N = 66), not vaccinated against HPV, were recruited from 1998 to 2008 into a longitudinal study. Self‐collected vaginal samples were obtained quarterly and tested for HPV by Linear Array HPV Genotyping Test (LA‐HPV). To explore low‐level persistence, a type‐specific nested PCR for HPV 16 (TSN‐PCR‐16) was developed. Women with HPV 16 detected by LA‐HPV had their negative swabs retested with TSN‐PCR‐16. Forty‐two participants with HPV 16, followed for a mean of 6.3 years, were analyzed. Using LA‐HPV, the median duration of HPV 16 detection was 428 days (SD 852.5 days). TSN‐PCR‐16 detected HPV 16 during periods of LA‐HPV non‐detection in samples from many women. Using a combination of LA‐HPV and TSN‐PCR‐16 results, the median duration of HPV 16 detection was 1,022.5 days (SD 943.7 days). The durations of detection differed significantly between the two methods (P = 0.0042) with a mean difference of 434.5 days. In adolescent females, duration of HPV 16 detection was significantly longer when TSN‐PCR‐16 was combined with LA‐HPV. Some apparently cleared HPV 16 could be shown to persist at low levels using nested PCR. J. Med. Virol. 83:1362–1369, 2011. © 2011 Wiley‐Liss, Inc.
Characterization of hepatitis B virus in turkish blood donors, and the prevalence of the SP1 splice variant
Authors: Cox Laura E. , Arslan Önder , Allain Jean‐Pierre 
Published: June 2011

AbstractHepatitis B is a disease of the liver that can manifest acutely, or persist chronically as a result of infection with the hepatitis B virus (HBV). Turkey has a moderate endemicity level of HBV infection, and all data published to date has shown this to be of genotype D, predominantly of subgenotype D1. However the sequences of very few full genomes have been published. The aim of this study was to characterize the molecular profile of hepatitis B virus in asymptomatic, first‐time Turkish blood donors. The results confirm that genotype D, subgenotype D1 is the most prevalent HBV strain in Turkey, accounting for 94% of cases. Subgenotypes D2 and D3 were present as minority strains (4% and 2%, respectively). A singly spliced HBV variant that is capable of forming defective HBV particles and has been associated with apoptosis and activation of T‐cell responses was also detected in 52.5% of samples screened, co‐circulating with wild type genomes. J. Med. Virol. 83:1321–1325, 2011. © 2011 Wiley‐Liss, Inc.
Effect of antiretroviral drugs on the quality of semen
Authors: Lambert‐Niclot Sidonie , Poirot Catherine , Tubiana Roland , Houssaini Allal , Soulié Cathia , Dominguez Stéphanie , Schubert Benoit , Prades Marie , Bonmarchand Manuela , Calvez Vincent , Flandre Philippe , Peytavin Gilles , Marcelin Anne‐Geneviève 
Published: June 2011

AbstractThe aim of this cross‐sectional study was to determine which antiretroviral drugs (ARVs) are associated with changes in the characteristics of semen and the impact of these ARVs according to their score penetration into the male genital compartment. Data from 144 men infected with HIV‐1 enrolled in an Assisted Reproductive Technology program were analyzed retrospectively. A seminal penetration score of ARV was based on the available literature. The nonparametric Kruskal–Wallis test and chi‐square test were used. There was no difference on sperm parameters between NRTI, NNRTI, or PI regimen. In patients receiving NRTIs or PIs no differences were observed between antiretrovirals of these classes. However, in patients receiving NNRTIs, nevirapine (n = 22) was associated with a higher percentage of progressively motile spermatozoa (P < 0.0001) versus efavirenz (n = 38) as well as vitality (P = 0.0004). No relationship was observed between semen quality and the penetration score. NRTIs and PIs were not associated with any semen changes. Nevirapine was associated with a better quality of semen versus efavirenz. It would be of interest to validate, improve and test our penetration score in a prospective study. J. Med. Virol. 83:1391–1394, 2011. © 2011 Wiley‐Liss, Inc.
Contribution of common and recently described respiratory viruses to annual hospitalizations in children in South Africa
Authors: Venter Marietjie , Lassaunière Ria , Kresfelder Tina Louise , Westerberg Yvette , Visser Adele 
Published: June 2011

AbstractThe contribution of viruses to lower respiratory tract disease in sub‐Saharan Africa where human immunodeficiency virus may exacerbate respiratory infections is not well defined. No data exist on some of these viruses for Southern Africa. Comprehensive molecular screening may define the role of these viruses as single and co‐infections in a population with a high HIV‐AIDS burden. To address this, children less than 5 years of age with respiratory infections from 3 public sector hospitals, Pretoria South Africa were screened for 14 respiratory viruses, by PCR over 2 years. Healthy control children from the same region were included. Rhinovirus was identified in 33% of patients, RSV (30.1%), PIV‐3 (7.8%), hBoV (6.1%), adenovirus (5.7%), hMPV (4.8%), influenza A (3.4%), coronavirus NL63 (2.1%), and OC43 (1.8%). PIV‐1, PIV‐2, CoV‐229E, ‐HKU1, and influenza B occurred in <1.5% of patients. Most cases with adenovirus, influenza A, hMPV, hBoV, coronaviruses, and WU virus occurred as co‐infections while RSV, PIV‐3, and rhinovirus were identified most frequently as the only respiratory pathogen. Rhinovirus but not RSV or PIV‐3 was also frequently identified in healthy controls. A higher HIV sero‐prevalence was noticed in patients with co‐infections although co‐infections were not associated with more severe disease. RSV, hPMV, PIV‐3, and influenza viruses had defined seasons while rhinovirus, adenovirus, and coronavirus infections occurred year round in this temporal region of sub‐Saharan Africa. J. Med. Virol. 83:1458–1468, 2011. © 2011 Wiley‐Liss, Inc.