bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sphingomyelin synthase overexpression increases cholesterol accumulation and decreases cholesterol secretion in liver cells
Authors: Yan Nianlong , Ding Tingbo , Dong Jibin , Li Yue , Wu Manping 
Published: March 2011

Abstract

Background
Studies have shown that plasma high density lipoprotein cholesterol levels are negatively correlated with the development of atherosclerosis, whereas epidemiological studies have also shown that plasma sphingomyelin level is an independent risk factor for atherosclerosis.

Methods
To evaluate the relationship between cellular sphingomyelin level and cholesterol metabolism, we created two cell lines that overexpressed sphingomyelin synthase 1 or 2 (SMS1 or SMS2), using the Tet-off expression system.

Results
We found that SMS1 or SMS2 overexpression in Huh7 cells, a human hepatoma cell line, significantly increased the levels of intracellular sphingomyelin, cholesterol, and apolipoprotein A-I and decreased levels of apolipoprotein A-I and cholesterol in the cell culture medium, implying a defect in both processes.

Conclusions
Our findings indicate that the manipulation of sphingomyelin synthase activity could influence the metabolism of sphingomyelin, cholesterol and apolipoprotein A-I.
Malignant peripheral nerve sheath tumor arising from the greater omentum: Case report
Authors: Miguchi Masashi , Takakura Yuji , Egi Hiroyuki , Hinoi Takao , Adachi Tomohiro , Kawaguchi Yasuo , Shinomura Manabu , Tokunaga Masakazu , Okajima Masazumi , Ohdan Hideki 
Published: March 2011

Abstract
Malignant peripheral nerve sheath tumors (MPNSTs) are rare soft tissue tumors that arise from a peripheral nerve or exhibit nerve sheath differentiation. Most of these tumors arise on the trunk, extremities, or head and neck regions; they are very rarely located in the abdominal cavity. The patient was a 71-year-old man who was referred to our hospital for a mass and pain in the right lower abdomen. Abdominal computed tomography revealed a large (9 × 9 cm), well-circumscribed, lobulated, heterogeneously enhanced mass in the pelvis. Exploratory laparotomy revealed a large mass in the greater omentum, and the tumor was completely excised. Histopathological analysis revealed that the tumor was composed of spindle cells with high mitotic activity. On staining the tumor, positive results were obtained for S-100 but negative results were obtained for c-kit, cluster of differentiation (CD)34, α-smooth muscle actin, and desmin. These findings strongly supported a diagnosis of MPNST primarily arising from the greater omentum. To the best of our knowledge, this is the first reported case of an MPNST arising from the greater omentum. In this report, we have described the case of a patient with an MPNST arising from the greater omentum and have discussed the clinical characteristics and management of MPNSTs.
Expression of ATP-sensitive potassium channels in human pregnant myometrium
Authors: Xu Chen , You Xingji , Gao Lu , Zhang Lanmei , Hu Rong , Hui Ning , Olson David M , Ni Xin 
Published: March 2011

Abstract

Background
Potassium channels play critical roles in the regulation of cell membrane potential, which is central to the excitability of myometrium. The ATP-sensitive potassium (KATP) channel is one of the most abundant potassium channels in myometrium. The objectives of this study were to investigate the protein expression of KATP channel in human myometrium and determine the levels of KATP channel in lower and upper segmental myometrium before and after onset of labour.

Methods
Both lower segmental (LS) and upper segmental (US) myometrial biopsies were collected at cesarean section from pregnant women not-in-labour (TNL) or in-labour (TL) at term. Protein expression level and cellular localization of four KATP channel subunits in US and LS myometrium were determined by Western blot analysis and immunohistochemistry, respectively. The contractile activity of myometrial strip was measured under isometric conditions.

Results
Four KATP channel subunits, namely Kir6.1, Kir6.2, SUR1 and SUR2B were identified in pregnant myometrium. While found in vascular myocytes, these subunits appear to be preferentially expressed in myometrial myocytes. Diazoxide, a KATP channel opener, inhibited the spontaneous contractility of pregnant myometrium, suggesting that the KATP channels are functional in human pregnant myometrium. Diazoxide was less potent in TL strips than that in TNL strips. Interestingly, expression of SUR1 was greater in TL than TNL tissues, although no differences were found for SUR2B in these two tissues. For both lower and upper segmental myometrium, Kir6.1 and Kir6.2 were less in TL compared with TNL tissues.

Conclusions
Functional KATP channels are expressed in human pregnant myometrium. Down-regulation of Kir6.1 and Kir6.2 expression in myometrium may contribute to the enhanced uterine contractility associated with the onset of labour.
Measuring physical activity during pregnancy
Authors: Harrison Cheryce L , Thompson Russell G , Teede Helena J , Lombard Catherine B 
Published: March 2011

Abstract

Background
Currently, little is known about physical activity patterns in pregnancy with prior estimates predominantly based on subjective assessment measures that are prone to error. Given the increasing obesity rates and the importance of physical activity in pregnancy, we evaluated the relationship and agreement between subjective and objective physical activity assessment tools to inform researchers and clinicians on optimal assessment of physical activity in pregnancy.

Methods
48 pregnant women between 26-28 weeks gestation were recruited. The Yamax pedometer and Actigraph accelerometer were worn for 5-7 days under free living conditions and thereafter the International Physical Activity Questionnaire (IPAQ) was completed. IPAQ and pedometer estimates of activity were compared to the more robust and accurate accelerometer data.

Results
Of 48 women recruited, 30 women completed the study (mean age: 33.6 ± 4.7 years; mean BMI: 31.2 ± 5.1 kg/m2) and 18 were excluded (failure to wear [n = 8] and incomplete data [n = 10]). The accelerometer and pedometer correlated significantly on estimation of daily steps (ρ = 0.69, p < 0.01) and had good absolute agreement with low systematic error (mean difference: 505 ± 1498 steps/day). Accelerometer and IPAQ estimates of total, light and moderate Metabolic Equivalent minutes/day (MET min-1 day-1) were not significantly correlated and there was poor absolute agreement. Relative to the accelerometer, the IPAQ under predicted daily total METs (105.76 ± 259.13 min-1 day-1) and light METs (255.55 ± 128.41 min-1 day-1) and over predicted moderate METs (-112.25 ± 166.41 min-1 day-1).

Conclusion
Compared with the accelerometer, the pedometer appears to provide a reliable estimate of physical activity in pregnancy, whereas the subjective IPAQ measure performed less accurately in this setting. Future research measuring activity in pregnancy should optimally encompass objective measures of physical activity.

Trial Registration
Australian New Zealand Clinical Trial Registry Number: ACTRN12608000233325. Registered 7/5/2008.
Does perception equal reality? Weight misperception in relation to weight-related attitudes and behaviors among overweight and obese US adults
Authors: Duncan Dustin T , Wolin Kathleen Y , Scharoun-Lee Melissa , Ding Eric L , Warner Erica T , Bennett Gary G 
Published: March 2011

Abstract

Background
Weight misperception might preclude the adoption of healthful weight-related attitudes and behaviors among overweight and obese individuals, yet limited research exists in this area. We examined associations between weight misperception and several weight-related attitudes and behaviors among a nationally representative sample of overweight and obese US adults.

Methods
Data from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) were used. Analyses included non-pregnant, overweight and obese (measured body mass index ≥ 25) adults aged 20 and older. Weight misperception was identified among those who reported themselves as "underweight" or "about the right weight". Outcome variables and sample sizes were: weight-loss attitudes/behaviors (wanting to weigh less and having tried to lose weight; n = 4,784); dietary intake (total energy intake; n = 4,894); and physical activity (meets 2008 US physical activity recommendations, insufficiently active, and sedentary; n = 5,401). Multivariable regression models were stratified by gender and race/ethnicity. Analyses were conducted in 2009-2010.

Results
These overweight/obese men and women who misperceived their weight were 71% (RR 0.29, 95% CI 0.25-0.34) and 65% (RR 0.35, 95% CI 0.29-0.42) less likely to report that they want to lose weight and 60% (RR 0.40, 95% CI 0.30-0.52) and 56% (RR 0.44, 95% CI 0.32-0.59) less likely to have tried to lose weight within the past year, respectively, compared to those who accurately perceived themselves as overweight. Blacks were particularly less likely to have tried to lose weight. Weight misperception was not a significant predictor of total energy intake among most subgroups, but was associated with lower total energy intake among Hispanic women (change -252.72, 95% CI -433.25, -72.18). Men who misperceived their weight were less likely (RR 0.68, 95% CI 0.52-0.89) to be insufficiently active (the strongest results were among Black men) and women who misperceived their weight were less likely (RR 0.74, 95% CI 0.54, 1.00, p = 0.047) to meet activity recommendations compared to being sedentary.

Conclusion
Overall, weight misperception among overweight and obese adults was associated with less likelihood of interest in or attempts at weight loss and less physical activity. These associations varied by gender and race/ethnicity. This study highlights the importance of focusing on inaccurate weight perceptions in targeted weight loss efforts.
Increase of plasma IL-9 and decrease of plasma IL-5, IL-7, and IFN-γ in patients with chronic heart failure
Authors: Cappuzzello Claudia , Di Vito Luca , Melchionna Roberta , Melillo Guido , Silvestri Lorena , Cesareo Eleonora , Crea Filippo , Liuzzo Giovanna , Facchiano Antonio , Capogrossi Maurizio C , Napolitano Monica 
Published: March 2011

Abstract

Background
Several cytokines are associated with the development and/or progression of chronic heart failure (CHF). Our aim was to look more closely at the cytokine networks involved in CHF, and to assess whether disease etiology affects cytokine expression. The study population was comprised of a) 69 patients with stable CHF, New York Heart Association (NYHA) II/IV classes, secondary to ischaemic (ICM) and non ischaemic dilated (NIDCM) cardiomyopathy and b) 16 control subjects. We analyzed and compared the plasma levels of 27 pro- and anti-inflammatory mediators, in the study population and assessed for any possible correlation with echocardiographic parameters and disease duration.

Methods
27 cytokines and growth factors were analyzed in the plasma of ICM- (n = 42) and NIDCM (n = 27) NYHA class II-IV patients vs age- and gender-matched controls (n = 16) by a beadbased multiplex immunoassay. Statistical analysis was performed by ANOVA followed by Tukey post-hoc test for multiple comparison.

Results
Macrophage inflammatory protein (MIP)-1β, Vascular endothelial growth factor (VEGF), interleukin (IL)-9, Monocyte chemotactic protein (MCP)-1, and IL-8 plasma levels were increased in both ICM and NIDCM groups vs controls. In contrast, IL-7, IL-5, and Interferon (IFN)-γ were decreased in both ICM and NIDCM groups as compared to controls. Plasma IL-6 and IL-1 β were increased in ICM and decreased in NIDCM, vs controls, respectively.
IL-9 levels inversely correlated, in ICM patients, with left ventricular ejection fraction (LVEF) while IL-5 plasma levels inversely correlated with disease duration, in NYHA III/IV ICM patients.
This is the first time that both an increase of plasma IL-9, and a decrease of plasma IL-5, IL-7 and IFN-γ have been reported in ICM as well as in NIDCM groups, vs controls. Interestingly, such cytokines are part of a network of genes whose expression levels change during chronic heart failure. The altered expression levels of MIP-1 β, VEGF, MCP-1, IL-1 β, IL-6, and IL-8, found in this study, are in keeping with previous reports.

Conclusions
The increase of plasma IL-9, and the decrease of plasma IL-5, IL-7 and IFN-γ in ICM as well as in NIDCM groups vs controls may contribute to get further insights into the inflammatory pathways involved in CHF.
Constructal blade shape in nanofluids
Authors: Bai Chao , Wang Liqiu 
Published: March 2011

AbstractBlade configuration of nanofluids has been proven to perform much better than dispersed configuration for some heat conduction systems. The analytical analysis and numerical calculation are made for the cylinder--shaped and regular-rectangular-prism--shaped building blocks of the blade-configured heat conduction systems (using nanofluids as the heat conduction media) to find the optimal cross-sectional shape for the nanoparticle blade under the same composing materials, composition ratio, volumetric heat generation rate, and total building block volume. The regular-triangular-prism--shaped blade has been proven to perform better than all the other three kinds of blades, namely, the regular-rectangular-prism--shaped blade, the regular-hexagonal-prism--shaped blade, and the cylinder--shaped blade. Thus, the regular-triangular-prism--shaped blade is selected as the optimally shaped blade for the two kinds of building blocks that are considered in this study. It is also proven that the constructal cylinder--regular-triangular-prism building block performs better than the constructal regular-rectangular-prism--regular-triangular-prism building block.
High-quality reduced graphene oxide-nanocrystalline platinum hybrid materials prepared by simultaneous co-reduction of graphene oxide and chloroplatinic acid
Authors: Wang Yinjie , Liu Jincheng , Liu Lei , Sun Darren Delai 
Published: March 2011

AbstractReduced graphene oxide-nanocrystalline platinum (RGO-Pt) hybrid materials were synthesized by simultaneous co-reduction of graphene oxide (GO) and chloroplatinic acid with sodium citrate in water at 80°C, of pH 7 and 10. The resultant RGO-Pt hybrid materials were characterized using transmission electron microscopy (TEM), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy, and thermogravimetric analysis. Platinum (Pt) nanoparticles were anchored randomly onto the reduced GO (RGO) sheets with average mean diameters of 1.76 (pH 7) and 1.93 nm (pH 10). The significant Pt diffraction peaks and the decreased intensity of (002) peak in the XRD patterns of RGO-Pt hybrid materials confirmed that the Pt nanoparticles were anchored onto the RGO sheets and intercalated into the stacked RGO layers at these two pH values. The Pt loadings for the hybrid materials were determined as 36.83 (pH 7) and 49.18% (pH 10) by mass using XPS analysis. With the assistance of oleylamine, the resultant RGO-Pt hybrid materials were soluble in the nonpolar organic solvents, and the dispersion could remain stable for several months.
Theory and simulation of photogeneration and transport in Si-SiO
x
superlattice absorbers
Authors: Aeberhard Urs 
Published: March 2011

AbstractSi-SiO
x
superlattices are among the candidates that have been proposed as high band gap absorber material in all-Si tandem solar cell devices. Owing to the large potential barriers for photoexited charge carriers, transport in these devices is restricted to quantum-confined superlattice states. As a consequence of the finite number of wells and large built-in fields, the electronic spectrum can deviate considerably from the minibands of a regular superlattice. In this article, a quantum-kinetic theory based on the non-equilibrium Green's function formalism for an effective mass Hamiltonian is used for investigating photogeneration and transport in such devices for arbitrary geometry and operating conditions. By including the coupling of electrons to both photons and phonons, the theory is able to provide a microscopic picture of indirect generation, carrier relaxation, and inter-well transport mechanisms beyond the ballistic regime.
Temperature- and thickness-dependent elastic moduli of polymer thin films
Authors: Ao Zhimin , Li Sean 
Published: March 2011

AbstractThe mechanical properties of polymer ultrathin films are usually different from those of their counterparts in bulk. Understanding the effect of thickness on the mechanical properties of these films is crucial for their applications. However, it is a great challenge to measure their elastic modulus experimentally with in situ heating. In this study, a thermodynamic model for temperature- (T) and thickness (h)-dependent elastic moduli of polymer thin films Ef(T,h) is developed with verification by the reported experimental data on polystyrene (PS) thin films. For the PS thin films on a passivated substrate, Ef(T,h) decreases with the decreasing film thickness, when h is less than 60 nm at ambient temperature. However, the onset thickness (h*), at which thickness Ef(T,h) deviates from the bulk value, can be modulated by T. h* becomes larger at higher T because of the depression of the quenching depth, which determines the thickness of the surface layer δ.
Defect-related hysteresis in nanotube-based nano-electromechanical systems
Authors: Tsetseris Leonidas , Pantelides Sokrates T 
Published: March 2011

AbstractThe electronic properties of multi-walled carbon nanotubes (MWCNTs) depend on the positions of their walls with respect to neighboring shells. This fact can enable several applications of MWCNTs as nano-electromechanical systems (NEMS). In this article, we report the findings of a first-principles study on the stability and dynamics of point defects in double-walled carbon nanotubes (DWCNTs) and their role in the response of the host systems under inter-tube displacement. Key defect-related effects, namely, sudden energy changes and hysteresis, are identified, and their relevance to a host of MWCNT-based NEMS is highlighted. The results also demonstrate the dependence of these effects on defect clustering and chirality of DWCNT shells.
Experimental study of combustion characteristics of nanoscale metal and metal oxide additives in biofuel (ethanol)
Authors: Jones Matthew , Li Calvin H , Afjeh Abdollah , Peterson GP 
Published: March 2011

AbstractAn experimental investigation of the combustion behavior of nano-aluminum (n-Al) and nano-aluminum oxide (n-Al2O3) particles stably suspended in biofuel (ethanol) as a secondary energy carrier was conducted. The heat of combustion (HoC) was studied using a modified static bomb calorimeter system. Combustion element composition and surface morphology were evaluated using a SEM/EDS system. N-Al and n-Al2O3 particles of 50- and 36-nm diameters, respectively, were utilized in this investigation. Combustion experiments were performed with volume fractions of 1, 3, 5, 7, and 10% for n-Al, and 0.5, 1, 3, and 5% for n-Al2O3. The results indicate that the amount of heat released from ethanol combustion increases almost linearly with n-Al concentration. N-Al volume fractions of 1 and 3% did not show enhancement in the average volumetric HoC, but higher volume fractions of 5, 7, and 10% increased the volumetric HoC by 5.82, 8.65, and 15.31%, respectively. N-Al2O3 and heavily passivated n-Al additives did not participate in combustion reactively, and there was no contribution from Al2O3 to the HoC in the tests. A combustion model that utilized Chemical Equilibrium with Applications was conducted as well and was shown to be in good agreement with the experimental results.
Viscosity affected by nanoparticle aggregation in Al2O3-water nanofluids
Authors: Duan Fei , Kwek Dingtian , Crivoi Alexandru 
Published: March 2011

AbstractAn investigation on viscosity was conducted 2 weeks after the Al2O3-water nanofluids having dispersants were prepared at the volume concentration of 1-5%. The shear stress was observed with a non-Newtonian behavior. On further ultrasonic agitation treatment, the nanofluids resumed as a Newtonian fluids. The relative viscosity increases as the volume concentrations increases. At 5% volume concentration, an increment was about 60% in the re-ultrasonication nanofluids in comparison with the base fluid. The microstructure analysis indicates that a higher nanoparticle aggregation had been observed in the nanofluids before re-ultrasonication.
Enhancing surface heat transfer by carbon nanofins: towards an alternative to nanofluids?
Authors: Chiavazzo Eliodoro , Asinari Pietro 
Published: March 2011

Abstract
Background
Nanofluids are suspensions of nanoparticles and fibers which have recently attracted much attention because of their superior thermal properties. Nevertheless, it was proven that, due to modest dispersion of nanoparticles, such high expectations often remain unmet. In this article, by introducing the notion of nanofin, a possible solution is envisioned, where nanostructures with high aspect-ratio are sparsely attached to a solid surface (to avoid a significant disturbance on the fluid dynamic structures), and act as efficient thermal bridges within the boundary layer. As a result, particles are only needed in a small region of the fluid, while dispersion can be controlled in advance through design and manufacturing processes.

Results
Toward the end of implementing the above idea, we focus on single carbon nanotubes to enhance heat transfer between a surface and a fluid in contact with it. First, we investigate the thermal conductivity of the latter nanostructures by means of classical non-equilibrium molecular dynamics simulations. Next, thermal conductance at the interface between a single wall carbon nanotube (nanofin) and water molecules is assessed by means of both steady-state and transient numerical experiments.

Conclusions
Numerical evidences suggest a pretty favorable thermal boundary conductance (order of 107 W·m-2·K-1) which makes carbon nanotubes potential candidates for constructing nanofinned surfaces.
Japanese encephalitis virus co-opts the ER-stress response protein GRP78 for viral infectivity
Authors: Wu Yi-Ping , Chang Chung-Ming , Hung Chun-Yu , Tsai Meng-Chieh , Schuyler Scott C , Wang Robert Yung-Liang 
Published: March 2011

Abstract
The serum-free medium from Japanese encephalitis virus (JEV) infected Baby Hamster Kidney-21 (BHK-21) cell cultures was analyzed by liquid chromatography tandem mass spectrometry (LC-MS) to identify host proteins that were secreted upon viral infection. Five proteins were identified, including the molecular chaperones Hsp90, GRP78, and Hsp70. The functional role of GRP78 in the JEV life cycle was then investigated. Co-migration of GRP78 with JEV particles in sucrose density gradients was observed and co-localization of viral E protein with GRP78 was detected by immunofluorescence analysis in vivo. Knockdown of GRP78 expression by siRNA did not effect viral RNA replication, but did impair mature viral production. Mature viruses that do not co-fractionate with GPR78 displayed a significant decrease in viral infectivity. Our results support the hypothesis that JEV co-opts host cell GPR78 for use in viral maturation and in subsequent cellular infections.