bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nanosilver induces minimal lung toxicity or inflammation in a subacute murine inhalation model
Authors: Stebounova Larissa V , Adamcakova-Dodd Andrea , Kim Jong Sung , Park Heaweon , O'Shaughnessy Patrick T , Grassian Vicki H , Thorne Peter S 
Published: February 2011

Abstract

Background
There is increasing interest in the environmental and health consequences of silver nanoparticles as the use of this material becomes widespread. Although human exposure to nanosilver is increasing, only a few studies address possible toxic effect of inhaled nanosilver. The objective of this study was to determine whether very small commercially available nanosilver induces pulmonary toxicity in mice following inhalation exposure.

Results
In this study, mice were exposed sub-acutely by inhalation to well-characterized nanosilver (3.3 mg/m3, 4 hours/day, 10 days, 5 ± 2 nm primary size). Toxicity was assessed by enumeration of total and differential cells, determination of total protein, lactate dehydrogenase activity and inflammatory cytokines in bronchoalveolar lavage fluid. Lungs were evaluated for histopathologic changes and the presence of silver. In contrast to published in vitro studies, minimal inflammatory response or toxicity was found following exposure to nanosilver in our in vivo study. The median retained dose of nanosilver in the lungs measured by inductively coupled plasma - optical emission spectroscopy (ICP-OES) was 31 μg/g lung (dry weight) immediately after the final exposure, 10 μg/g following exposure and a 3-wk rest period and zero in sham-exposed controls. Dissolution studies showed that nanosilver did not dissolve in solutions mimicking the intracellular or extracellular milieu.

Conclusions
Mice exposed to nanosilver showed minimal pulmonary inflammation or cytotoxicity following sub-acute exposures. However, longer term exposures with higher lung burdens of nanosilver are needed to ensure that there are no chronic effects and to evaluate possible translocation to other organs.
Mathematical model of uptake and metabolism of arsenic(III) in human hepatocytes - Incorporation of cellular antioxidant response and threshold-dependent behavior
Authors: Stamatelos Spyros K , Brinkerhoff Christopher J , Isukapalli Sastry S , Georgopoulos Panos G 
Published: February 2011

Abstract

Background
Arsenic is an environmental pollutant, potent human toxicant, and oxidative stress agent with a multiplicity of health effects associated with both acute and chronic exposures. A semi-mechanistic cellular-level toxicokinetic (TK) model was developed in order to describe the uptake, biotransformation and clearance of arsenical species in human hepatocytes. Notable features of this model are the incorporation of arsenic-glutathione complex formation and a "switch-like" formulation to describe the antioxidant response of hepatocytes to arsenic exposure.

Results
The cellular-level TK model applies mass action kinetics in order to predict the concentrations of trivalent and pentavalent arsenicals in hepatocytes. The model simulates uptake of arsenite (iAsIII) via aquaporin isozymes 9 (AQP9s), glutathione (GSH) conjugation, methylation by arsenic methyltransferase (AS3MT), efflux through multidrug resistant proteins (MRPs) and the induced antioxidant response via thioredoxin reductase (TR) activity. The model was parameterized by optimization of model estimates for arsenite (iAsIII), monomethylated (MMA) and dimethylated (DMA) arsenicals concentrations with time-course experimental data in human hepatocytes for a time span of 48 hours, and dose-response data at 24 hours for a range of arsenite concentrations from 0.1 to 10 μM. Global sensitivity analysis of the model showed that at low doses the transport parameters had a dominant role, whereas at higher doses the biotransformation parameters were the most significant. A parametric comparison of the TK model with an analogous model developed for rat hepatocytes from the literature demonstrated that the biotransformation of arsenite (e.g. GSH conjugation) has a large role in explaining the variation in methylation between rats and humans.

Conclusions
The cellular-level TK model captures the temporal modes of arsenical accumulation in human hepatocytes. It highlighted the key biological processes that influence arsenic metabolism by explicitly modelling the metabolic network of GSH-adducts formation. The parametric comparison with the TK model developed for rats suggests that the variability in GSH conjugation could have an important role in inter-species variability of arsenical methylation. The TK model can be incorporated into larger-scale physiologically based toxicokinetic (PBTK) models of arsenic for improving the estimates of PBTK model parameters.
Upregulation of microRNA-451 increases cisplatin sensitivity of non-small cell lung cancer cell line (A549)
Authors: Bian Hai-Bo , Pan Xuan , Yang Jin-Song , Wang Zhao-Xia , De Wei 
Published: February 2011

Abstract

Background
Recently, miR-451 as a tumor suppressor has been reported in other studies. However, whether miR-451 can affect the sensitivity of non-small cell lung cancer (NSCLC) cells to cisplatin (DDP) remains unclear. The aim of this study is to evaluate the roles of miR-451 in the sensitivity of NSCLC cells to DDP.

Methods
Quantitative RT-PCR assay was performed to detect the expression of miR-451 in 10 pairs of NSCLC and noncancerous tissue samples. pcDNA-GW/EmGFP-miR-451 was stably transfected into NSCLC cell line (A549). Then, the effects of miR-451 upregulation on growth, colony formation and apoptosis of A549 cells were investigated. Finally, the effects of miR-451 upregulation on in vitro and in vivo sensitivity of A549 cells of DDP were also determined.

Results
The level of miR-451 expression in NSCLC tissues was significantly higher than that in corresponding noncancerous tissues. Ectopic overexpression of miR-451 could significantly inhibit growth and induce apoptosis of A549 cells. Moreover, ectopic overexpression of miR-451 could sensitize A549 cells to DDP possibly by increasing DDP-induced apoptosis which might be associated with the inactivation of Akt signaling pathway.

Conclusions
This study demonstrated for the first time that combination of DDP application with miR-451 upregulation might be a potential strategy for the treatment of human NSCLC.
Insulin-Induced Oxidative Stress Up-Regulates Heme Oxygenase-1 via Diverse Signaling Cascades in the C2 Skeletal Myoblast Cell Line
Authors: Aggeli Ioanna-Katerina , Theofilatos Dimitris , Beis Isidoros , Gaitanaki Catherine 
Published: February 2011

AbstractImpaired insulin sensitivity (insulin resistance) is a common denominator in many metabolic disorders, exerting pleiotropic effects on skeletal muscle, liver, and adipose tissue function. Heme oxygenase-1 (HOX-1), the rate-limiting enzyme in heme catabolism, has recently been shown to confer an antidiabetic effect while regulating cellular redox-buffering capacity. Therefore, in the present study, we probed into the mechanisms underlying the effect of insulin on HOX-1 in C2 skeletal myoblasts. Hence, insulin was found to suppress C2 myoblasts viability via stimulation of oxidative stress, with HOX-1 counteracting this action. Insulin induced HOX-1 expression in a time- and dose-dependent manner, an effect attenuated by selective inhibitors of ERK1/2 (PD98059), Src (4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d] pyrimidine), and c-Jun terminal kinases 1 and 2 (SP600125) pathways. Furthermore, nuclear factor-κB role in insulin-induced HOX-1 up-regulation was verified, with ERK1/2, Src, and c-Jun terminal kinases 1 and 2 mediating p65-nuclear factor-κB subunit phosphorylation. Overall, our novel findings highlight for the first time the transduction mechanisms mediating HOX-1 induction in insulin-treated C2 myoblasts. This effect was established to be cell type specific because insulin failed to promote HOX-1 expression in HepG2 hepatoma cells. Deciphering the signaling networks involved in insulin-stimulated HOX-1 up-regulation is of prominent significance because it may potentially contribute to elucidation of the mechanisms involved in associated metabolic pathologies.
Photoinduced Triplet States of Photoconductive TTF Derivatives Including a Fluorescent Group
Authors: Furukawa Ko , Sugishima Yasuo , Fujiwara Hideki , Nakamura Toshikazu 
Published: February 2011

Abstract
The spin dynamics of photoconductive tetrathiafulvalene (TTF) derivatives containing 2,5-diphenyl-1,3,4-oxadiazole (PPD) was examined using time-resolved electron spin resonance (TR-ESR) spectroscopy. TR-ESR signals of a frozen solution sample under visible excitation were attributed to the excited triplet state T1, which was populated via intersystem crossing from the excited singlet state S1 as confirmed by TR-ESR spectral simulations. From DFT calculations, the spin-density distribution of the T1 state was found to be concentrated around the linker between the TTF and PPD molecules.
Convenient Synthesis of Dibenzo[a,h]anthracenes and Picenes via C–H Arylation of Acetophenones with Arenediboronates
Authors: Kitazawa Kentaroh , Kochi Takuya , Nitani Masashi , Ie Yutaka , Aso Yoshio , Kakiuchi Fumitoshi 
Published: February 2011

Abstract
A new convenient method for the synthesis of dibenzo[a,h]anthracenes and picenes using ruthenium-catalyzed regioselective C–H arylation of aromatic ketones has been developed. Acetophenone derivatives and 1,4-benzenediboronates were coupled in 2:1 ratios to form p-terphenyl derivatives. Conversion of the acetyl group to an ethynyl group, followed by cycloaromatization provided the desired fused aromatic compounds. An organic field-effect transistor fabricated from one of these products gave moderate hole mobility.
Evaluation of the Menarini/ARKRAY ADAMS A1c HA-8180V analyser for HbA1c
Authors: Weykamp Cas , Lenters-Westra Erna , van der Vuurst Hans , Slingerland Robbert , Siebelder Carla , Visser-Dekkers Willeke 
Published: February 2011

Abstract

Background: We report an evaluation of the Menarini/ARKRAY ADAMS A1c HA-8180V analyser (HA-8180V), the fifth generation Menarini/ARKRAY ion-exchange HPLC for the measurement of HbA1c.

Methods: We evaluated the analytical performance, the measurement of haemoglobin variants and the performance in comparison to major analytical methods.

Results: Within-run, between-run and total CV were 0.2%, 0.4% and 0.7% at low HbA1c concentrations and 0.2%, 0.2% and 0.4% at high HbA1c concentrations, respectively. Trueness revealed a maximum deviation of 0.8 mmol/mol (IFCC units) or 0.1% (NGSP units) over the relevant analytical range. Linearity, carry-over and linear drift were excellent. Labile-HbA1c, carbamylated haemoglobin, icteric samples and variation in hematocrit did not affect HbA1c outcome. Haemoglobin variants AS, AC and F do not affect HbA1c outcome and are explicitly identified and correctly quantified. HbA1c can not be measured in samples with AE and AD, but these variants are identified correctly. In comparison to other methods used at present, the HA-8180V shows excellent performance.

Conclusions: The HA-8180V performs at a high level and is fit for any clinical application.
A case of primary aldosteronism in pregnancy: do LH and GNRH receptors have a potential role in regulating aldosterone secretion?
Authors: Albiger N M , Sartorato P , Mariniello B , Iacobone M , Finco I , Fassina A , Mantero F 
Published: February 2011

ObjectiveThe mechanisms inducing steroidogenesis in primary aldosteronism (PA) remain poorly defined. It was recently demonstrated that some G-protein-coupled receptors are abnormally expressed in aldosterone-producing adenomas (APA). We evaluated the potential role of LH and GNRH receptors (LHR (or LHCGR) and GNRHR) in regulating aldosterone secretion in a patient with APA arising during pregnancy (index case) and in a subset of other patients with PA.Patients and methodsGNRH test was performed in the index case, 11 other PA, and 5 controls. GNRHR and LHR expressions were examined in 23 APA and 6 normal tissues.ResultsAldosterone response increased significantly (114%) in the index case after GNRH test was performed preoperatively, while it was blunted after adrenalectomy. Aldosterone also increased after human chorionic gonadotropin and triptorelin stimulation. A partial aldosterone response to GNRH was observed in other 7/11 PA, while a significant response was observed in two patients. Controls did not respond to GNRH test.GNRHR was overexpressed and LHR expression was moderate in the APA tissue from the index case. Moreover, LHR was found in normal adrenals and overexpressed in 6/22 APA. GNRHR was overexpressed in 6/22 APA, 2 of them with a 95- and 109-fold higher expression than normal. A correlation between the clinical and molecular findings was observed in five out of seven patients.ConclusionWe describe a case of PA diagnosed during pregnancy, which appeared to correlate with aberrant LHR and GNRHR expression. Our findings suggest that a subset of patients with PA has aberrant LHR and GNRHR expression, which could modulate aldosterone secretion.
A novel HESX1 splice mutation causes isolated GH deficiency by interfering with mRNA processing
Authors: Vivenza Daniela , Godi Michela , Faienza Maria Felicia , Mellone Simona , Moia Stefania , Rapa Anna , Petri Antonella , Bellone Simonetta , Riccomagno Stefania , Cavallo Luciano , Giordano Mara , Bona Gianni 
Published: February 2011

ObjectiveMutations inHESX1represent a rare cause of GH deficiency (GHD) associated with a broad spectrum of other anomalies. We searched for causative mutations in a cohort of 244 Italian patients affected by combined and isolated GHD (IGHD).MethodsTheHESX1gene-coding region and exon–intron boundaries were screened by denaturing HPLC scanning.ResultsA novel mutation adjacent to the invariant donor splice site of intron 2 (c.357+3G>A) was identified at the heterozygous state in an IGHD patient. Thein vitroandin vivomRNA analysis of the wild-typeHESX1allele revealed the presence of the whole cDNA and two isoforms lacking exon 2 and exons 2–3 respectively. The mutantHESX1allele yielded only two splicing products, the whole cDNA and the cDNA missing exons 2–3, whereas the mRNA lacking exon 2 was absent. Anin vitroassay demonstrated that the exon 2-deleted mRNA, predicting a prematurely truncated protein, is subjected to nonsense-mediated mRNA decay (NMD).ConclusionsThec.357+3G>Amutation prevents the generation of one of the alternative isoforms normally produced by the wild-type allele, predicting a truncated HESX1 protein. The mutation is likely to cause IGHD in the heterozygous patient by interfering with the downregulation ofHESX1expression mediated by alternative splicing and NMD.Our results open new insight into the mechanism ofHESX1regulation suggesting that the coupling of alternative splicing and NMD might play a fundamental role in directing theHESX1expression, and that the alteration of this process might lead to severe consequences.
Investigation of Pressure Monitoring Methods for Xing1-2 Field, Daqing
Authors: Zhang X. , Gao P. , Yin D. 
Published: February 2011

Abstract
In this research, both reservoir simulation and well testing were employed to investigate the average reservoir pressure in the Xing 1-2, a multilayer sandstone reservoir. The concrete methods included the well testing, Peaceman, and volumetric weighted average method (VWA). The average reservoir pressures for the last three years of the monitoring wells were calculated. The results showed diversities among three methods at each well pattern. The factors which caused diversities in three methods have been categorized, like the geological uncertainties, production impact, the difference in mathematical methods, etc. The wells in low pressure zones were detected and analyzed. By reducing the influence of referenceless interpretations, the system provided more accurate interpretations. The results were also used to optimize the monitored wells and to offer reference for the improvement of the injection and production system.
The Use of Wireline Formation Tester for Optimization of Conventional Well Test Design and Interpretation
Authors: Kumar Vikash , Dunlap James , Klimentos Theodore , Khan Zuber A. , Farooqui M. Y. 
Published: February 2011

Abstract
During the exploration and appraisal phases field data is collected for the determination of reservoir parameters which will govern the Field Development and production strategy. Permeability-thickness, hydrocarbon properties and reservoir extent are critical parameters acquired during this phase which are used to evaluate expected well and reservoir performance. Dynamic Flow tests, combined with Downhole Fluid Analysis and fluid samples are commonly used to obtain this information. The most common flow tests today use either Wireline Formation Testers (WFT) for small scale tests, or Drill Stem Tests (DST) for larger scale flow tests. This paper will describe a workflow in which the information acquired from the small scale WFT tests can be used to optimize the design and execution of the larger, and typically more costly, DST’s. The ultimate goal of the workflow is to increase the value of the information obtained, and the overall success rate of the DST’s performed.
Accurate Inflow Profile Prediction of Horizontal Wells Using a Newly Developed Coupled Reservoir and Wellbore Flow Equations
Authors: Kabir Akim , Vargas Jose A. 
Published: February 2011

Abstract
Despite their widespread use, horizontal wells continue to underperform compared to our expectations. This is mainly due to lack of our understanding and ability to predict accurate inflow profile as a result of pressure drop along the wellbore. Stand- alone inflow equations do not calculate accurate inflow profile. In order to get the best performance from a horizontal well, a uniform inflow profile achievement is important. This cannot be addressed unless the inflow profile is quantified.
In this work we describe coupling of some analytical reservoir flow models with wellbore flow models for predicting ac- curate inflow profile of long horizontal wells. S. D. Joshi and Babu-Odeh inflow equation options have been implemented in this coupled solution. Continuity equations are used to calculate pressure drop in the wellbore. A coupling algorithm has been proposed which converges reasonably quickly giving accurate picture of the inflow profile. Results obtained from this work have been compared with some published work which is encouraging. Also results of a few case studies have been discussed which show the effect of a few completion/ fluid parameters on pressure & flux profile of these (horizontal) wells. The ulti- mate goal of this work is to come up with a stand-alone computer program which will be able to model not only the inflow performance relationship of these wells, but also will be able to come up with detailed inflow profiles along the completed interval of horizontal wells for various completion options with varying parameters.
Application of Telemetry Technology In High-Pressure Wells To Improve Data Accuracy in Drill Stem Tests
Authors: Haddad Josmar , Salguero Alejandro , Jaimes Carrie 
Published: February 2011

Abstract
Drill-stem testing (DST) has been used for many years in the oilfield to establish reliable reservoir characterization. The DST data are used to provide estimated production, fluid analysis, and to help design the final completion and production facilities.
More recently, discoveries in abnormal pressure gradients and deep formations have not only pushed the capabilities of traditional equipment and procedures, but also increased the safety hazards inherent to DST operations. At surface, high pressures, the presence of H2S, and toxic well fluids increase the difficulty in deployment of real-time data acquisition and sampling equipment via wireline. Downhole, the high hydrostatic pressures normally found in deep environments can hinder the operation of the downhole tools. Often, to achieve high hydrostatic pressures, the operator is forced to use drilling muds which may have very low pressure transmissibility and solids problems that interfere with annulus-pressure/pulse-response tools.
The need to improve the quality of information gathered during DSTs in hostile environments has driven a major oilfield engineering company to research concepts that could improve capabilities of traditional DST systems.
This research led to the development of a novel telemetry system that uses acoustic bi-directional acoustic transmission through the tubing string. This system, compact and easy to deploy into the well, provides real-time data-acquisition flexibility in various depths in the string, enabling the constant monitoring of the wellbore conditions throughout the DST. It’s design, applications, and ability to simplify job procedures, reduce risks, and improve quality of information when linked to data acquisition and tool operation, will be the focus of this paper.
This new system provides greater efficiency in acquiring data in deeper, high-pressure DST environments than are currently possible with the standard methods.
Comparing Wireline Formation Tester Derived Productivity Index to Drill Stem Test
Authors: Khong Chee Kin , Li Chen , Ayan Cosan , Xu Liqiang , Jun Cai , Guo Shusheng , Wang Wu Mu , Zhongtian Hao , Fuxi Pan , Zhongjian Tan , Jun Yang Hong 
Published: February 2011

Abstract
Drill stem test (DST) derived average effective permeability and productivity is our industry's accepted standard but DST expenses are not always justified especially in development wells. Although zonal contribution could be measured by production logging survey but this requires an additional well intervention operation and most likely interruption of production as well. Zonal productivity modeled correctly in a well is of immense value for reservoir management. In exploration well, accurate productivity index prior to DST is invaluable for operational planning, while in development well accurate productivity index is crucial for completion design.
If dynamic data is not available, zonal productivity had been estimated based on permeability derived from petrophysical log data. Single probe open-hole wireline formation tester (OH-WFT) pretest mobility is often used to calibrate log data estimated permeability. However, OH-WFT pretest almost always measure the invaded or drilling induced damaged zone and is at a scale much smaller than DST derived average permeability.
Interval Pressure Transient Test using wireline formation tester estimate permeability further away from invaded or drilling induced damaged zone provides a more accurate permeability measurement. Multi-probe or Single-probe WFT is an attractive option when borehole condition does not allow wireline formation tester with straddle packer (WFT-PA) operation.
For Single-probe WFT data, permeability anisotropy has to be assumed while permeability anisotropy can be calculated from Multi-probe or Packer-probe pressure data. WFT estimated permeability from pressure transient analysis allows zonal productivity to be calculated, utilizing also pressure, temperature, fluid data, zonal thickness, completed interval and formation dip data.
Log data modeled zonal productivity from static data had resulted in off-forecast compared to actual well performance. In this paper, multi-probe and packer-probe wireline formation tester permeability test is used to derive zonal productivity. This productivity estimate is compared to actual DST productivity index.