bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of substrate stiffness on early human embryonic stem cell differentiation
Authors: Eroshenko Nikolai , Ramachandran Rukmani , Yadavalli Vamsi K , Rao Raj R 
Published: March 2013

Abstract

Background
The pluripotency and self renewing properties of human embryonic stem cells (hESC) make them a valuable tool in the fields of developmental biology, pharmacology and regenerative medicine. Therefore, there exists immense interest in devising strategies for hESC propagation and differentiation. Methods involving simulation of the native stem cell microenvironment, both chemical and physical, have received a lot of attention in recent years. Equally important is evidence that cells can also sense the mechanical properties of their microenvironment. In this study, we test the hypothesis that hESCs accept mechanical cues for differentiation from the substrate by culturing them on flexible polydimethylsiloxane (PDMS) of varying stiffness.

Results
PDMS substrates were prepared using available commercial formulations and characterized for stiffness, surface properties and efficiency of cell attachment and proliferation. Across different substrate stiffness, cell numbers, cell attachment and cell surface area were found to be similar. Expression of pluripotency markers decreased with increased time in culture across all PDMS substrates of varying stiffness. Analysis of gene expression of differentiation markers indicates that the differentiation process becomes less stochastic with longer culture times.

Conclusions
We evaluated the utility of PDMS substrates for stem cell propagation and substrate mediated differentiation. The stiffness affected gene expression of pluripotent and differentiation markers with results indicating that these substrate systems could potentially be used to direct hESC fate towards early mesodermal lineages. This study suggests that coupled with soluble factors, PDMS substrates could potentially be useful in generating defined populations of differentiated cells.
3-M syndrome associated with growth hormone deficiency: 18 year follow-up of a patient
Authors: Meazza Cristina , Lausch Ekkehard , Pagani Sara , Bozzola Elena , Calcaterra Valeria , Superti-Furga Andrea , Silengo Margherita , Bozzola Mauro 
Published: March 2013

Abstract
3-M syndrome is a rare autosomal recessive disorder that causes short stature, unusual facial features and skeletal abnormalities. Mutations in the CUL7, OBSL1 and CCDC8 genes could be responsible for 3-M syndrome.
Here we describe the growth and evolution of dismorphic features of an Italian boy with 3-M syndrome and growth hormone deficiency (GHD) from birth until adulthood. He was born full term with a very low birth weight (2400 g=−3.36 standard deviation score, SDS) and length (40.0 cm =−6.53 SDS). At birth he presented with a broad, fleshy nose with anteverted nostrils, thick and patulous lips, a square chin, curvilinear shaped eyebrows without synophrys, short thorax and long slender bones. Then, during childhood tall vertebral bodies, hip dislocation, transverse chest groove, winged scapulae and hyperextensible joints became more evident and the diagnosis of 3-M syndrome was made; this was also confirmed by the finding of a homozygous deletion in exon 18 of the CUL7 gene, which has not been previously described.
The patient also exhibited severe GHD (GH <5 ng/ml) and from the age of 18 months was treated with rhGH. Notwithstanding the early start of therapy and good compliance, his growth rate was always very low, except for the first two years of treatment and he achieved a final height of 132 cm (−6.42 SDS).
Possible rheumatoid arthritis subtypes in terms of rheumatoid factor, depression, diagnostic delay and emotional expression: an exploratory case-control study
Authors: Tillmann Taavi , Krishnadas Rajeev , Cavanagh Jonathan , Petrides KV 
Published: March 2013

Abstract
Introduction
Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis has been implicated in the pathology of rheumatoid arthritis (RA), particularly as vulnerable personality types are exposed to chronic stress. Emotions are powerful modulators of stress responses. However, little is known about whether patients with RA process emotions differently to matched controls. In this study we: 1) assessed whether the trait emotional intelligence (trait EI) scores of patients with RA differ from healthy controls at the facet level; 2) explored any subgroups in RA, in terms of trait EI and common risk factors.

Methods
A total of 637 patients with RA were compared to 496 controls on the trait EI Questionnaire (TEIQue). RA subgroups were explored in terms of trait EI, rheumatoid factor status (RF+/-), depression and time from onset of symptoms until diagnosis (diagnostic delay).

Results
The RA group rated themselves lower on Adaptability, Stress-management, Emotion management, Self-esteem, Sociability, Assertiveness, Impulsiveness and Well-being, and higher on Empathy and Relationships than healthy controls. The RF- subtype reported more time with depression (25.2 vs. 11.3 months), a longer diagnostic delay (3.0 vs. 1.7 years), and greater emotional expression (5.15 vs. 4.72), than the RF+ subtype. These differences were significant at the P <0.05 level, but not following strict Bonferroni corrections and should therefore be treated as indicative only. RF- patients with a longer diagnostic delay reported depression lasting three times longer (42.7 months), when compared to three other subtypes (11.0 to 12.7 months).

Conclusions
RA patients and controls differ in their emotion-related personality traits, as operationalized by trait EI. These differences may make people with RA more susceptible to chronic stress and HPA-axis dysregulation. RA may be a highly heterogeneous illness where at least two subtypes may be characterized by personality, psychiatric and immunological differences. RF- status, as well as diagnostic delay and emotional expression, may predict future risk of depression. Research on the causes of RA could benefit from a systems science approach.
Frequency-dependent seismic anisotropy due to fractures: Fluid flow versus scattering
Authors: Baird Alan F. , Kendall J.-Michael , Angus Doug A. 
Published: March 2013

Anisotropy is a useful attribute for the detection and characterization of aligned fracture sets in petroleum reservoirs. Unfortunately, many of the traditional effective medium theories for modeling the seismic properties of fractured rock are insensitive to the size of the constituent fractures. For example, the same pattern of anisotropy may be produced by a high concentration of small, stiff cracks or by a lower concentration of large, compliant fractures. The distinction between these models is important for assessing permeability anisotropy because fluid flow is dominated by the largest fractures. One method to gain further insight is through the analysis of frequency-dependent shear-wave splitting in microseismic data because fracture compliance is frequency dependent, and microseismic data are relatively rich in frequency content. We compared two potential mechanisms causing frequency-dependent compliance of fractures: (1) squirt flow in fractured porous rock and (2) wave scattering over rough fractures. Both models showed a sensitivity to average fracture size or compliance of the constituent fractures, and thus they provide a potential means to differentiate between anisotropy produced by small cracks or large fractures. We used both mechanisms to model frequency-dependent anisotropy data obtained from a fractured gas reservoir and invert for fracture parameters. Under certain conditions, the squirt-flow mechanism can cause significant frequency dependence in the microseismic band. However, the model is highly sensitive to the empirically derived mineral-scale relaxation time, which is poorly known and requires laboratory measurements to constrain. Conversely, producing a similar frequency response using the scattering model requires implausible fracture parameters; therefore, the squirt-flow model appears to be the most likely mechanism for microseismic applications. At higher frequencies, however, scattering may become more significant. Care should be taken when upscaling ultrasonic laboratory results for field-scale problems because different mechanisms may be at play within different frequency bands.
Insulin-Like Growth Factor Binding Protein 2 (IGFBP-2) Promotes Growth and Survival of Breast Epithelial Cells: Novel Regulation of the Estrogen Receptor
Authors: Foulstone Emily J. , Zeng Li , Perks Claire M. , Holly Jeff M. P. 
Published: March 2013

AbstractIn breast tumors IGF binding protein-2 (IGFBP-2) is elevated, and the presence of IGFBP-2 has been shown to correlate with malignancy. However, how IGFBP-2 contributes to the malignant state is still unclear. Silencing IGFBP-2 blocked cell proliferation and in MCF-7 cells increased cell death, indicating that IGFBP-2 was acting in both a mitogenic and a survival capacity. Exogenous IGFBP-2 acting via integrin receptors to reduce phosphatase and tensin homolog deleted from chromosome 10 (PTEN) levels protected these cells against death induced by various chemotherapeutic agents. This was dependent on a functional estrogen receptor (ER)-α because silencing ER-α blocked the ability of IGFBP-2 to confer cell survival. Loss of IGFBP-2 increased levels of PTEN and improved chemosensitivity of the cells, confirming its role as a survival factor. Silencing IGFBP-2 had no effect on the response to IGF-II, but responses to estrogen and tamoxifen were no longer observed due to loss of ER-α, which could be prevented by the inhibition of PTEN. Conversely, exogenous IGFBP-2 increased ER-α mRNA and protein in both normal and cancer cells via its interaction with integrin receptors. These actions of IGFBP-2 on ER-α involved the IGF-I receptor and activation of phosphatidylinositol 3-kinase in the cancer cells but were independent of this in normal breast cells. The production of IGFBP-2 by breast cancer cells enhances their proliferative potential, increases their survival, and protects them against chemotherapy-induced death. IGFBP-2 not only modulates IGFs and directly regulates PTEN but also has a role in maintaining ER-α expression.
CYP2J3 Gene Delivery Up-Regulated Adiponectin Expression via Reduced Endoplasmic Reticulum Stress in Adipocytes
Authors: Xu Xizhen , Tu Ling , Feng Wenjing , Ma Ben , Li Rui , Zheng Changlong , Li Geng , Wang Dao Wen 
Published: March 2013

Abstract
Ample evidences demonstrate that cytochrome P450 (CYP) epoxygenases metabolize arachidonic acid into epoxyeicosatrienoic acids (EETs), which play crucial and diverse roles in cardiovascular homeostasis. We and others have identified that EETs exert a beneficial role on insulin resistance and diabetes. This study investigated the effects of CYP2J3 epoxygenase gene delivery on adiponectin expression in rats treated with high-fat (HF) diet. CYP2J3 gene delivery in vivo increased EET generation, enhanced adiponectin expression and secretion and accompanied by activation of adiponectin downstream signaling, and decreased insulin resistance as determined by plasma insulin levels, insulin resistance index and glucose tolerance test, as well as phosphorylation of protein kinase B in both liver and muscle. Furthermore, CYP2J3 overexpression prevented HF diet-induced endoplasmic reticulum (ER) stress in adipose tissue of rats. Also, CYP2J3 gene transfection and exogenous administration of EETs inhibited thapsigargin-induced ER stress with increased adiponectin expression and secretion in differentiated 3T3-L1 adipocytes. Thus, CYP2J3 gene delivery up-regulated adiponectin expression and excretion in adipose tissue of rats treated with HF diet through inhibition of ER stress, which can decrease adiponectin expression. These results further highlight the beneficial roles of the CYP epoxygenase 2J3 and its metabolites EETs on adiponectin expression and secretion.
The Androgen Metabolite, 5α-Androstane-3β,17β-Diol (3β-Diol), Activates the Oxytocin Promoter Through an Estrogen Receptor-β Pathway
Authors: Hiroi Ryoko , Lacagnina Anthony F. , Hinds Laura R. , Carbone David G. , Uht Rosalie M. , Handa Robert J. 
Published: March 2013

AbstractTestosterone has been shown to suppress the acute stress-induced activation of the hypothalamic-pituitary-adrenal axis; however, the mechanisms underlying this response remain unclear. The hypothalamic-pituitary-adrenal axis is regulated by a neuroendocrine subpopulation of medial parvocellular neurons in the paraventricular nucleus of the hypothalamus (PVN). These neurons are devoid of androgen receptors (ARs). Therefore, a possibility is that the PVN target neurons respond to a metabolite in the testosterone catabolic pathway via an AR-independent mechanism. The dihydrotestosterone metabolite, 5α-androstane-3β,17β-diol (3β-diol), binds and activates estrogen receptor-β (ER-β), the predominant ER in the PVN. In the PVN, ER-β is coexpressed with oxytocin (OT). Therefore, we tested the hypothesis that 3β-diol regulates OT expression through ER-β activation. Treatment of ovariectomized rats with estradiol benzoate or 3β-diol for 4 days increased OT mRNA selectively in the midcaudal, but not rostral PVN compared with vehicle-treated controls. 3β-Diol treatment also increased OT mRNA in the hypothalamic N38 cell line in vitro. The functional interactions between 3β-diol and ER-β with the human OT promoter were examined using an OT promoter-luciferase reporter construct (OT-luc). In a dose-dependent manner, 3β-diol treatment increased OT-luc activity when cells were cotransfected with ER-β, but not ER-α. The 3β-diol–induced OT-luc activity was reduced by deletion of the promoter region containing the composite hormone response element (cHRE). Point mutations of the cHRE also prevented OT-luc activation by 3β-diol. These results indicate that 3β-diol induces OT promoter activity via ER-β–cHRE interactions.
Immuno-DNA-directed Assembly of Heterotypic Multicellular Systems
Authors: Shomorony Andre , Fan Rong 
Published: March 2013

Abstract
An immuno-DNA-directed assembly technique based on bifunctional conjugates of uniquely designed-ssDNA codes and antibodies specific to cell surface receptors enables rapid assembly of heterotypic cells into multicellular systems. It is a versatile and modular approach, and upon further development may find applications in microtissue engineering.
Shear-response Emulsion Prepared through Discontinuous Cubic Liquid Crystal
Authors: Yamashita Yuji , Sato Toshiko , Nagasawa Teruaki , Kubota Yoshiki , Musashi Mina , Kawamura Kimio , Koyama Masako , Sakamoto Kazutami , Yamaguchi Yoko 
Published: March 2013

Abstract
A novel emulsion and its preparation route were established in a quasi-ternary system with a nonionic surfactant, water, glycerol, and squalane. This emulsion is simply obtained by diluting a discontinuous cubic liquid crystal. It consists of giant floc in part, corresponding to the fraction of the discontinuous cubic liquid crystal. Contrary to common emulsification, our emulsion has an unique and abnormal shear-response: the semistable structure is breaking down gradually by applying a mechanical energy.
Particle Size Characterization of Commercial Raw Materials and Graphite nanoparticles of a Refractory Bricks Mix of the System Al2O3-SiC-C
Authors: Paniagua A. M. , Martinez J. , Mauro V. , Diaz E. 
Published: March 2013

ABSTRACTIn this work was studied the partial substitution in the design of a refractory mix of the fine crystalline graphite for prefabricate nanoparticles of the seam source of graphite, improving the refractory properties of the material, getting a better resistant to the chemical attack by the slag and steel liquid metal. The raw materials and nanoparticles of crystalline graphite were characterized by X-ray diffraction (XRD), Sherrer equation, and scanning electron microscopy (SEM). The nanoparticles size determines the crystalline of the graphite used in the mixes obtained after different steps of mechanic milling. The nanoparticles of materials were added to the mixes in different proportions. The commercial raw materials used for this investigation were: commercial silicon carbide high purity (97% SiC), calcined bauxite (85% Al2O3), alpha calcined alumina, and crystalline graphite (94% C). Additionally, six different sizes of graphite nanoparticles were selected. The particle size of the initial commercial graphite was 0.044mm and the final nanoparticles obtained in this investigation by mechanic milling was 18 nm. The measurement of the particle size of the nanoparticles was made by the Scherrer equation, XRD and SEM.
Preparation of Lithium Aluminum Layered Double Hydroxide from Ammonium Dawsonite and Lithium Carbonate
Authors: Soto C. A. Contreras , Ramos-Ramírez E. , Zamudio V. Reyes , Macías J. I. 
Published: March 2013

ABSTRACTAluminum lithium hydroxide carbonate hydrate, also known as Al/Li layered double hydroxide or Al-Li hydrotalcite-like compound [Al2Li(OH)6]2CO3•nH2O, was prepared by reaction of lithium carbonate with ammonium dawsonite [NH4Al(OH)2CO3]. The reaction of ammonium dawsonite with a lithium carbonate satured solution at different temperatures and lithium carbonate concentrations was studied. The obtained solids were characterized by differential thermal analysis (DTA), thermogravimetry (TGA), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and transmission electron microscopy (TEM). By this method, crystalline Li/Al LDH [Al2Li(OH)6]2CO3·3H2O can be obtained at 60 °C and 4 h reaction time.
Luminescence in a Ba(Ti,Zr)O3 Films Deposited by Ultrasonic Spray Pyrolysis Method
Authors: Medina D. Y. , Hernandez R. T. , Hernandez I. , Orozco S. 
Published: March 2013

ABSTRACTThe Ba(Ti,Zr)O3 powders was synthesized for many methods because its properties as a piezoelectric, dielectric and ferroelectric material that insert it as an functional material, but there is little information in the studied of its optical properties. In this work Ba(Ti,Zr)O3films were produced by ultrasonic spray pyrolysis method for optical applications. The precursors used were an barium acetyl-acetonate, titanium acetyl-acetonate, and zirconium acetyl-acetonate powders dissolved in a N-N, dimethylformamide solution. Optical and morphological properties of the films shown a non crystalline structure and its emission spectra shown a broad and intense luminescence at 468nm which correspond to visible emission in the green region.
Realistic simulation of polycrystalline CIGS absorbers and experimental verification
Authors: Maragliano C. , Stefancich M. , Rampino S. , Colace L. 
Published: March 2013

AbstractCu(InGa)Se2 solar cells modeling is challenging due to their complex electronic structure, to the presence of interface states between layer and grains and to the microcrystalline structure of the absorber. Here we present a ISE-TCAD based realistic absorber 3D model, with the specific objective to take into account, among several effects, these challenging aspects. The CdS/Cu(InGa)Se2 solar cell is modeled as an array of columnar microcells, connected in parallel, mimicking the polycrystalline nature of the absorber. The model optical and electrical parameters are optimized based on a review of available experimental material characterization and realization results. Simulation outcomes are compared with experimental data in order to validate the model.
Photoluminescent Effects on the Temperature Coefficient of Multi-Junction Solar Cells
Authors: Mokri Alaeddine , Emziane Mahieddine 
Published: March 2013

ABSTRACTIn this work, we re-evaluate the temperature coefficient in multi-junction solar cells by including the effects of radiative coupling (i.e. re-absorption of emitted photons within the cell) and eliminating radiative losses towards the substrate (i.e. use of a back mirror). The model developed is for two-junction devices, and it takes into account: the number of terminals, the energy bandgaps of the sub-cells, the light concentration, and whether a back mirror is used or not. The temperature coefficients obtained are compared with the case where no luminescent effects are considered. The results show that, in two-terminal and four-terminal devices, the sensitivity to temperature is almost the same whether luminescent effects are taken into account or not. However, these effects are most significant in three-terminal devices. In four-terminal devices, the results show that these effects depend to a large extent on the materials used, the design of the system, i.e. on the effectiveness of radiative exchange between the cells involved.
Large Pre- and Postexercise Rapid-Acting Insulin Reductions Preserve Glycemia and Prevent Early- but Not Late-Onset Hypoglycemia in Patients With Type 1 Diabetes
Authors: Campbell Matthew D. , Walker Mark , Trenell Michael I. , Jakovljevic Djordje G. , Stevenson Emma J. , Bracken Richard M. , Bain Stephen C. , West Daniel J. 
Published: March 2013

OBJECTIVETo examine the acute and 24-h glycemic responses to reductions in postexercise rapid-acting insulin dose in type 1 diabetic patients.RESEARCH DESIGN AND METHODSAfter preliminary testing, 11 male patients (24 ± 2 years, HbA1c 7.7 ± 0.3%; 61 ± 3.4 mmol/mol) attended the laboratory on three mornings. Patients consumed a standardized breakfast (1 g carbohydrate ⋅ kg−1 BM; 380 ± 10 kcal) and self-administered a 25% rapid-acting insulin dose 60 min prior to performing 45 min of treadmill running at 72.5 ± 0.9% VO2peak. At 60 min postexercise, patients ingested a meal (1 g carbohydrate ⋅ kg−1 BM; 660 ± 21 kcal) and administered a Full, 75%, or 50% rapid-acting insulin dose. Blood glucose concentrations were measured for 3 h postmeal. Interstitial glucose was recorded for 20 h after leaving the laboratory using a continuous glucose monitoring system.RESULTSAll glycemic responses were similar across conditions up to 60 min postexercise. After the postexercise meal, blood glucose was preserved under 50%, but declined under Full and 75%. Thence at 3 h, blood glucose was highest under 50% (50% [10.4 ± 1.2] vs. Full [6.2 ± 0.7] and 75% [7.6 ± 1.2 mmol ⋅ L−1], P = 0.029); throughout this period, all patients were protected against hypoglycemia under 50% (blood glucose ≤3.9; Full, n = 5; 75%, n = 2; 50%, n = 0). Fifty percent continued to protect patients against hypoglycemia for a further 4 h under free-living conditions. However, late-evening and nocturnal glycemia were similar; as a consequence, late-onset hypoglycemia was experienced under all conditions.CONCLUSIONSA 25% pre-exercise and 50% postexercise rapid-acting insulin dose preserves glycemia and protects patients against early-onset hypoglycemia (≤8 h). However, this strategy does not protect against late-onset postexercise hypoglycemia.