bluuebunny/crossref_metadata_2025_split huggingface dataset:
Murine amniotic fluid stem cells contribute mesenchymal but not epithelial components to reconstituted mammary ducts
Authors: Klemmt Petra AB , Vafaizadeh Vida , Groner Bernd 
Published: August 2010

Abstract
Introduction
Amniotic fluid harbors cells indicative of all three germ layers, and pluripotent fetal amniotic fluid stem cells (AFSs) are considered potentially valuable for applications in cellular therapy and tissue engineering. We investigated whether it is possible to direct the cell fate of AFSs in vivo by transplantation experiments into a particular microenvironment, the mammary fat pad. This microenvironment provides the prerequisites to study stem cell function and the communication between mesenchymal and epithelial cells. On clearance of the endogenous epithelium, the ductal tree can be reconstituted by the transfer of exogenously provided mammary stem cells. Analogously, exogenously provided stem cells from other tissues can be investigated for their potential to contribute to mammary gland regeneration.

Methods
We derived pluripotent murine AFSs, measured the expression of stem cell markers, and confirmed their in vitro differentiation potential. AFSs were transplanted into cleared and non cleared fat pads of immunocompromised mice to evaluate their ability to assume particular cell fates under the instructive conditions of the fat-pad microenvironment and the hormonal stimulation during pregnancy.

Results
Transplantation of AFSs into cleared fat pads alone or in the presence of exogenous mammary epithelial cells caused their differentiation into stroma and adipocytes and replaced endogenous mesenchymal components surrounding the ducts in co-transplantation experiments. Similarly, transplantation of AFSs into fat pads that had not been previously cleared led to AFS-derived stromal cells surrounding the elongating endogenous ducts. AFSs expressed the marker protein α-SMA, but did not integrate into the myoepithelial cell layer of the ducts in virgin mice. With pregnancy, a small number of AFS-derived cells were present in acinar structures.

Conclusions
Our data demonstrate that the microenvironmental cues of the mammary fat pad cause AFSs to participate in mammary gland regeneration by providing mesenchymal components to emerging glandular structures, but do not incorporate or differentiate into ductal epithelial cells.
Human Epidermal Growth Factor Receptor 2 Assessment in a Case-Control Study: Comparison of Fluorescence In Situ Hybridization and Quantitative Reverse Transcription Polymerase Chain Reaction Performed by Central Laboratories
Authors: Baehner Frederick L. , Achacoso Ninah , Maddala Tara , Shak Steve , Quesenberry Charles P. , Goldstein Lynn C. , Gown Allen M. , Habel Laurel A. 
Published: August 2010

Purpose The optimal method to assess human epidermal growth factor receptor 2 (HER2) status remains highly controversial. Before reporting patient HER2 results, American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAP) guidelines mandate that laboratories demonstrate ≥ 95% concordance to another approved laboratory or methodology. Here, we compare central laboratory HER2 assessed by fluorescence in situ hybridization (FISH) and quantitative reverse transcriptase polymerase chain reaction (RT-PCR) using Oncotype DX in lymph node–negative, chemotherapy-untreated patients from a large Kaiser Permanente case-control study. Patients and Methods Breast cancer specimens from the Kaiser–Genomic Health study were examined. Central FISH assessment of HER2 amplification and polysomy 17 was conducted by PhenoPath Laboratories (ratios > 2.2, 1.8 to 2.2, and < 1.8 define HER2 positive, HER2 equivocal, and HER2 negative, respectively). HER2 expression by RT-PCR was conducted using Oncotype DX by Genomic Health (normalized expression units ≥ 11.5, 10.7 to < 11.5, and < 10.7 define HER2 positive, HER2 equivocal, and HER2 negative, respectively). Concordance analyses followed ASCO/CAP guidelines. Results HER2 concordance by central FISH and central RT-PCR was 97% (95% CI, 96% to 99%). Twelve percent (67 of 568 patients) and 11% (60 of 568 patients) of patients were HER2 positive by RT-PCR and FISH, respectively. HER2-positive patients had increased odds of dying from breast cancer compared with HER2-negative patients. Polysomy 17 was demonstrated in 12.5% of all patients and 33% of FISH-positive patients. Nineteen of 20 FISH-positive patients with polysomy 17 were also RT-PCR HER2 positive. Although not statistically significantly different, HER2-positive/polysomy 17 patients tended to have the worst prognosis, followed by HER2-positive/eusomic, HER2-negative/polysomy 17, and HER2-negative/eusomic patients. Conclusion There is a high degree of concordance between central FISH and quantitative RT-PCR using Oncotype DX for HER2 status, and the assay warrants additional study in a trastuzumab-treated population.
Delays in Adjuvant Chemotherapy Treatment Among Patients With Breast Cancer Are More Likely in African American and Hispanic Populations: A National Cohort Study 2004-2006
Authors: Fedewa Stacey A. , Ward Elizabeth M. , Stewart Andrew K. , Edge Stephen B. 
Published: August 2010

Purpose Previous studies have indicated poorer survival among women receiving adjuvant chemotherapy > 90 days after surgery compared with women receiving adjuvant chemotherapy within 90 days of surgery. Patients and Methods Women diagnosed between 2004 and 2006 with invasive breast cancer (stages I to III) and treated with surgery and adjuvant chemotherapy were selected from the National Cancer Database (n = 107,587). We evaluated factors associated with prolonged time to start adjuvant chemotherapy (≥ 60 and ≥ 90 days after surgical resection) using multivariable log binomial models to estimate risk ratios (RRs) and 95% CIs. Results The average time to adjuvant chemotherapy was 41.46 days (± 24.46 days). Overall, 85.2% and 95.8% of women received adjuvant chemotherapy within 60 and 90 days of surgery, respectively. African American and Hispanic patients had higher risk of 60-day delay (RR, 1.36; 95% CI, 1.30 to 1.41 and RR, 1.31; 95% CI, 1.23 to 1.39, respectively) and 90-day delay (RR, 1.56; 95% CI, 1.44 to 1.69 and RR, 1.41; 95% CI, 1.26 to 1.59, respectively) compared with white patients. Insurance type, stage, comorbidity, and facility type were also associated with adjuvant chemotherapy delay. Conclusion The majority of women in our study received adjuvant chemotherapy within the time frame (90 days) for which there is no evidence of poorer outcome. However, the rate of delay varied by patient and by clinical and facility factors. Future studies on the role of structural, physician, clinical, and patient factors in adjuvant chemotherapy delay in populations of women with higher rates of delay and potential interventions are needed.
Uptake and metabolism of arsenate, methylarsonate and arsenobetaine by axenic cultures of the phytoplankton Dunaliella tertiolecta
Authors: Duncan Elliott , Foster Simon , Maher William 
Published: August 2010

Abstract
Axenic cultures of the phytoplankton Dunaliella tertiolecta were dosed with either arsenate [As(V)], methylarsonate (MA) or arsenobetaine (AB) at environmentally realistic concentrations (2 μg l-1) to investigate incorporation and transformation of arsenic species. Total arsenic concentrations in cultures dosed with As(V) were significantly higher than those dosed with MA and AB (6–10 μg g-1 compared to 1–3 μg g-1). Arsenic concentrations in As(V)-dosed cultures increased over time, whereas arsenic concentrations in MA- and AB-dosed cultures remained constant, indicating that As(V) is rapidly and continuously incorporated into the cell in comparison to MA and AB. Arsenic was found predominantly in the residue fractions (29–55%) of all cultures, irrespective of culture age. This was attributed to the ability of inorganic arsenic as arsenite [As(III)] to bind to proteins and/or phytochelatins. 2-Dimethylarsinoylethanol (DMAE) was the main arsenic species found in lipid cell fractions. Within the water-soluble and residue cell fractions, arsenic was isolated primarily as As(V), although it is likely the extraction procedure may have converted some As(III) to As(V). Small amounts of As(III), MA, dimethylarsinate (DMA) and arsenoribosides were also found in the lipid and water soluble As fractions. All cultures showed an increase in DMA and arsenoriboside species over time. The significance of these results is that while AB, the major arsenical in marine animals, is not produced or accumulated by this phytoplankton species, the possible precursors to AB formation are produced.
Meiotic Chromosome Segregation in Triploid Strains ofSaccharomyces cerevisiae
Authors: Charles Jordan St , Hamilton Monica L , Petes Thomas D 
Published: August 2010

AbstractMeiosis in triploids results in four highly aneuploid gametes because six copies of each homolog must be segregated into four meiotic products. Using DNA microarrays and other physical approaches, we examined meiotic chromosome segregation in triploid strains of Saccharomyces cerevisiae. In most tetrads with four viable spores, two of the spores had two copies of a given homolog and two spores had only one copy. Chromosomes segregated randomly into viable spores without preferences for generating near haploid or near diploid spores. Using single-nucleotide polymorphisms, we showed that, in most tetrads, all three pairs of homologs recombined. Strains derived from some of the aneuploid spore colonies had very high frequencies of mitotic chromosome loss, resulting in genetically diverse populations of cells.
Prevalence of Streptococcal Pharyngitis and Streptococcal Carriage in Children: A Meta-analysis
Authors: Shaikh Nader , Leonard Erica , Martin Judith M. 
Published: August 2010

OBJECTIVES:
Prevalence estimates can help clinicians make informed decisions regarding diagnostic testing of children who present with symptoms of pharyngitis. We conducted a meta-analysis to determine the (1) prevalence of streptococcal infection among children who presented with sore throat and (2) prevalence of streptococcal carriage among asymptomatic children.

METHODS:
We searched Medline for articles on pediatric streptococcal pharyngitis. We included articles in our review when they contained data on the prevalence of group A Streptococcus (GAS) from pharyngeal specimens in children who were younger than 18 years. Two evaluators independently reviewed, rated, and abstracted data from each article. Prevalence estimates were pooled in a meta-analysis and stratified according to age group.

RESULTS:
Of the 266 articles retrieved, 29 met all inclusion criteria. Among children of all ages who present with sore throat, the pooled prevalence of GAS was 37% (95% confidence interval [CI]: 32%–43%). Children who were younger than 5 years had a lower prevalence of GAS (24% [95% CI: 21%–26%]). The prevalence of GAS carriage among well children with no signs or symptoms of pharyngitis was 12% (95% CI: 9%–14%).

CONCLUSIONS:
Prevalence rates of GAS disease and carriage varied by age; children who were younger than 5 years had lower rates of throat cultures that were positive for GAS.
Influence of Deposition Parameters on Surface Texturing of ZnO:Al Films Prepared by In-line RF Magnetron Sputtering
Authors: Cho Jun-Sik , Kim Young-Jin , Lee Jeong Chul , Park Sang-Hyun , Yoon Kyung Hoon 
Published: August 2010

AbstractA systematic study on the effect of sputtering deposition parameters on material properties of Al doped ZnO (ZnO:Al) films prepared by an in-line rf magnetron sputtering and on surface morphology of the films after wet etching process was carried out. For application to silicon thin film solar cells as a front electrode, the as-deposited films were surface-textured by a dilute HCl solution to improve the light scattering properties such as haze and angle resolved distribution of scattered light on the film surfaces. The microstructure of as-deposited films is affected significantly by the working pressure and film compactness decreases with increasing working pressure from 1.5 mTorr to 10 mTorr. High quality ZnO:Al films with electrical resistivity of 4.25 × 10-4 Ω cm and optical transmittance of 80% in a visible range are obtained at low working pressure of 1.5 mTorr and substrate temperature of 100℃. Crater-like surface morphologies are observed on the textured ZnO:Al films after wet etching. The size and shape of craters are closely dependent on the microstructure and film compactness of as-deposited films. Haze values of the textured ZnO:Al films are improved in a whole wavelength of 300 – 1100 nm compared to commercial SnO2:F films (Asahi U type) and incident light on the textured films is scattered effectively with 30° angle.
Increasing the Potential of Bioactive Glass as a Scaffold for Bone Tissue Engineering
Authors: Ammar Mohamed , Kaplan Max , Quinn Therese , Jedlicka Sabrina 
Published: August 2010

AbstractBioactive glass is known for its potential as a bone scaffold due to its ability to stimulate osteogenesis and differentiation of stem cells into bone cells. In an attempt to investigate if we can increase these potentials, we decorated the structure of the bioactive glass made by the sol-gel technique with 3 peptides sequences from different proteins known for their potentials to stimulate the osteogensis process (fibronectin, BMP-2 and protein kinase CKI). This material was tested with Human Mesenchymal Stem Cells (hMSCs) and MC-3T3 preosteoblasts to see the difference in the effect on uncommitted and committed cells. The bioactive glass sol with and without the peptides was dip coated onto glass cover slips, leading to a film of the material, surface decorated with the peptides of choice. The two cell types were seeded onto the materials in standard proliferation medium without additives for differentiation induction. Cells were also grown on tissue culture treated cover slips with and without differentiation induction media as positive and negative controls, respectively. The cells were grown on the materials for a total of five weeks, and were tested at four time points (weekly from week two) by immunocytochemical assays to investigate the levels of different osteogenic markers (osteopontin, osteocalcin and osteonectin) and by qRT-PCR to investigate the mRNA potential of the same proteins. On the native bioactive glass samples, the hMSCs and the MC-3T3s adhered poorly. On peptide-decorated samples, the hMSC adhered poorly, however, the MC-3T3 cells appear to differentiate at a rate that is equal to or faster than the positive control, indicating that the peptide effect is similar to that achieved by traditional BMP-2 soluble protein techniques. This supports our hypothesis that adding specific peptide sequences known for their effects in cells adhesion, proliferation and differentiation can increase the potential of the bioactive glass as a scaffold for bone tissue engineering. The data, however, leads to some questions regarding the MC-3T3 cell model for use in further studies.
Optically Active Defects in an InAsP/InP Quantum Well Monolithically Integrated on SrTiO3 (001)
Authors: Cheng Jun , El Akra Ahiram , Bru-Chevallier Catherine , Patriarche Gilles , LARGEAU Ludovic , Regreny Philippe , Hollinger Guy , Saint-Girons Guillaume 
Published: August 2010

AbstractThe optical properties of an InAsP/InP quantum well grown on a SrTiO3(001) substrate are analyzed. At 13K, the photoluminescence (PL) yield of the well is comparable to that of a reference well grown on an InP substrate. Increasing the temperature leads to the activation of non-radiative mechanisms for the sample grown on SrTiO3. The main non-radiative channel is related to the thermal excitation of the holes to the first heavy hole excited state, followed by the non-radiative recombination of the carriers on twins and/or domain boundaries, in the immediate vicinity of the well.
Island Structured Dielectric Thin Films by Scalable Self-Assembly
Authors: Sriram Sharath , Bhaskaran Madhu , Mitchell Arnan 
Published: August 2010

AbstractA self-assembly driven process to synthesize island-structured dielectric films is presented. An intermetallic reaction in platinized silicon substrates provides preferential growth sites for the complex oxide dielectric (strontium-doped lead zirconate titanate) layer. Microscopy and spectroscopy analyses have been used to propose a mechanism for this structuring process. This provides a simple and scalable process to synthesize films with increased surface area for sensors, especially those materials with a complex chemistry.
GPIIb/IIIa Receptor Antagonism Using Small Molecules Provides no Additive Long-Term Protection after Percutaneous Coronary Intervention as Compared to Clopidogrel Plus Aspirin
Authors: Schiariti Michele , Saladini Angela , Papalia Francesco , Grillo Placido , Nesta Cristina , Cuturello Domenico , Missiroli Bindo , Puddu Paolo Emilio 
Published: August 2010

Background:
There is some controversy as to whether tirofiban or eptifibatide, two small anti-aggregating drugs (AAD), may reduce the incidence of composite ischemic events within one year in patients undergoing percutaneous coronary intervention (PCI) in the real clinical world.

Methods:
We compared consecutive patients on oral double AAD (with clopidogrel and aspirin) who underwent PCI (n=207) and patients who were on single AAD and received a second AAD, just prior to PCI, and either high-dose tirofiban or double-bolus eptifibatide (double AAD plus small molecules group, n=666). The primary end point (incidence of composite ischemic events within one year) included death, acute myocardial infarction, unstable angina, stent thrombosis or repeat PCI or coronary bypass surgery (related to the target vessel PCI failure) and was modelled by Cox’s regression.

Results:
There were 89 composite ischemic events: 24 (11.6%) in double AAD alone and 65 (9.8%) in double AAD plus small molecules groups (log-rank test: p=0.36). Incidences by type of ischemic events were similar between the 2 groups. Based on 21 potential covariates fitted simultaneously, adjusted hazard ratios (HR and 95% confidence intervals) showed that age (HR 1.03, 1.01-1.06, p=0.01), diabetes (HR 1.68, 1.01-2.79, p=0.05) and intra aortic balloon pump (HR 5.12, 2.36-11.10, p=0.0001) were significant risk factors whereas thrombolysis by tenecteplase (HR 0.35, 0.13-0.98, p=0.05) and having had hypertension or anti-hypertensive treatment (HR 0.58, 0.36-0.93, p=0.03) were significant protectors for events. Whether small molecules were present provided a non significant additional benefit as compared to double AAD alone (HR 0.83, 0.51-1.36, p=0.46). Pre-PCI CK-MB were not useful to predict events (HR 1.01, 0.99-1.01, p=0.17).

Conclusions:
In clinical world patients undergoing PCI (rescue plus primary <13%) while on double AAD, based on clopidogrel plus aspirin, small molecules (tirofiban or eptifibatide) provided no additive long-term protection against the occurrence of composite ischemic events whereas thrombolysis by tenecteplase did.
Quality-of-Life Measures in Children and Adults With Type 1 Diabetes
Authors:   Juvenile Diabetes Research Foundation Continuous Glucose Monitoring Study Group
Published: August 2010

OBJECTIVE
To evaluate the impact of continuous glucose monitoring (CGM) on quality of life (QOL) among individuals with type 1 diabetes.

RESEARCH DESIGN AND METHODS
In a multicenter trial, 451 children and adults with type 1 diabetes were randomly assigned to CGM treatment or the control group. Generic and diabetes-specific QOL questionnaires were completed at baseline and 26 weeks by all participants and parents of participants &lt;18 years old, and the CGM satisfaction scale was completed by the CGM group (participants and parents) at 26 weeks.

RESULTS
After 26 weeks, QOL scores remained largely unchanged for both the treatment and the control group, although there was a slight difference favoring the adult CGM group on several subscales (P &lt; 0.05). There was substantial satisfaction with CGM technology after 26 weeks among participants and parents.

CONCLUSIONS
Baseline QOL was high, and the measures showed little change with CGM use, although a high level of CGM satisfaction was reported.
Durability of heavyweight concrete containing barite
Authors: Binici Hanifi 
Published: August 2010

AbstractThe supplementary waste barite aggregates deposit in Osmaniye, southern Turkey, has been estimated at around 500000000 tons based on 2007 records. The aim of the present study is to investigate the durability of concrete incorporating waste barite as coarse and river sand (RS), granule blast furnace slag (GBFS), granule basaltic pumice (GBP) and ≤4 mm granule barite (B) as fine aggregates. The properties of the fresh concrete determined included the air content, slump, slump loss and setting time. They also included the compressive strength, flexural and splitting tensile strengths and Young's modulus of elasticity, resistance to abrasion and sulphate resistance of hardened concrete. Besides these, control mortars were prepared with crushed limestone aggregates. The influence of waste barite as coarse aggregates and RS, GBFS, GBP and B as fine aggregates on the durability of the concretes was evaluated. The mass attenuation coefficients were calculated at photon energies of 1 keV to 100 GeV using XCOM and the obtained results were compared with the measurements at 0.66 and 1.25 MeV.The results showed the possibility of using these waste barite aggregates in the production of heavy concretes. In several cases, some of these properties have been improved. Durability of the concrete made with these waste aggregates was improved. Thus, these materials should be preferably used as aggregates in heavyweight concrete production.
Thermomechanical fatigue of 1.4849 cast steel – experiments and life prediction using a fracture mechanics approach
Authors: Seifert Thomas , Schweizer Christoph , Schlesinger Michael , Möser Martin , Eibl Martin 
Published: August 2010

AbstractIn this paper the thermomechanical fatigue properties of 1.4849 cast steel, which is used for exhaust manifolds and turbochargers, are investigated and a fracture mechanics based approach is used for fatigue life prediction. Isothermal low-cycle fatigue tests and thermomechanical fatigue tests are conducted in the temperature range from room temperature up to 1 000 °C. Fractographic investigations show that fracture occurs predominantly intergranularly at 600 °C, whereas mixed transgranular and intergranular crack growth is found otherwise. The methodology for fatigue life prediction is based on a time and temperature dependent cyclic plasticity model, which describes the transient stresses and strains, and on a law for time and temperature dependent microcrack growth. The crack growth law assumes that the increment in crack length in each cycle, da/dN, is correlated with the cyclic crack-tip opening displacement, δCTOD. An analytical fracture mechanics based estimate of δCTOD is used, which is derived for non-isothermal loadings. The fatigue lives of the low-cycle and the thermomechanical fatigue tests are predicted well with the model. Only predictions for the low-cycle fatigue tests at 600 °C, where integranular fracture is predominant, are non-conservative.