bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cytotoxic evaluation of Melia azedarach in comparison with, Azadirachta indica and its phytochemical investigation
Authors: Jafari Samineh , Saeidnia Soodabeh , Hajimehdipoor Homa , Ardekani Mohammad Reza Shams , Faramarzi Mohammad Ali , Hadjiakhoondi Abbas , Khanavi Mahnaz 
Published: May 2013

Abstract

Background

Melia azedarach L. is an important medicinal plant that is used for variety of ailments in Iranian traditional medicine. Azadirachta indica A. Juss is its allied species and possesses similar properties and effects. The present study was undertaken to investigate anticancer activity of these M. azedarach in comparison with A. indica on cancer cell lines and also to evaluate their safety in humans by testing them on normal cell line. The study also aimed to determine the active components that are responsible for medicinal effects of M. azedarach in traditional usages.

Methods
In this study, the cytotoxic activity of crude extracts from M. azedarach and A. indica leaves, pulps and seeds as well as three main fractions of their leaf extracts were assayed against HT-29, A-549, MCF-7 and HepG-2 and MDBK cell lines. MTT assay was used to evaluate their cytotoxic activities. Methanol leaf fraction of M. azedarach as the safest leaf fraction in terms of cytotoxicity was subjected for phytochemical study.

Results
Results of the present study indicated that seed kernel extract of M. azedarach had the highest cytotoxic activity and selectivity to cancer cell lines (IC50 range of 8.18- 60.10 Î¼g mL-1). In contrast to crude seed extract of A. indica, crude pulp and crude leaf extracts of this plant showed remarkably stronger anti-prolifrative activity (IC50 ranges of 83.45 - 212.16 Î¼g mL-1 and 34.11- 95.51 Î¼g mL-1 respectively) than those of M. azedarach (all IC50 values of both plants > 650 Î¼g mL-1). The phytochemical analysis led to the isolation of four flavonol 3-O-glycosides including rutin, kaempferol-3-O-robinobioside, kaempferol-3-O-rutinoside and isoquercetin along with a purin nucleoside, Î²-adenosine.

Conclusions
The anti-prolifrative potentials of extracts from different parts of M. azedarach and A. indica were determined. By comparison, methanol leaf fraction of M. azedarach seems to be safer in terms of cytotoxicity. Our study shows that flavonols are abundant in the leaves of M. azedarach and these compounds seem to be responsible for many of medicinal effects exploited in the traditional uses.
Strategies for obtaining unpublished drug trial data: a qualitative interview study
Authors: Wolfe Nicole , Gøtzsche Peter C , Bero Lisa 
Published: May 2013

Abstract

Background
Authors of systematic reviews have difficulty obtaining unpublished data for their reviews. This project aimed to provide an in-depth description of the experiences of authors in searching for and gaining access to unpublished data for their systematic reviews, and to give guidance on best practices for identifying, obtaining and using unpublished data.

Methods
This is a qualitative study analyzing in-depth interviews with authors of systematic reviews who have published Cochrane reviews or published systematic reviews outside of The Cochrane Library. We included participants who 1) were the first or senior author of a published systematic review of a drug intervention, 2) had expertise in conducting systematic reviews, searching for data, and assessing methodological biases, and 3) were able to participate in an interview in English. We used non-random sampling techniques to identify potential participants. Eighteen Cochrane authors were contacted and 16 agreed to be interviewed (89% response rate). Twenty-four non-Cochrane authors were contacted and 16 were interviewed (67% response rate).

Results
Respondents had different understandings of what was meant by unpublished data, including specific outcomes and methodological details. Contacting study authors was the most common method used to obtain unpublished data and the value of regulatory agencies as a data source was underappreciated. Using the data obtained was time consuming and labor intensive. Respondents described the collaboration with other colleagues and/or students required to organize, manage and use the data in their reviews, generally developing and using templates, spreadsheets and computer programs for data extraction and analysis. Respondents had a shared belief that data should be accessible but some had concerns about sharing their own data. Respondents believed that obtaining unpublished data for reviews has important public health implications. There was widespread support for government intervention to ensure open access to trial data.

Conclusions
Respondents uniformly agreed that the benefit of identifying unpublished data was worth the effort and was necessary to identify the true harms and benefits of drugs. Recent actions by government, such as increased availability of trial data from the European Medicines Agency, may make it easier to acquire critical drug trial data.
Measuring quality in diabetes care: an expert-based statistical approach
Authors: Bertsimas Dimitris , Czerwinski David , Kane Michael 
Published: May 2013

Abstract
We present a methodology for using health insurance claims data to monitor quality of care. The method uses a statistical model trained on the quality ratings of a medical expert. In a pilot study, the expert rated the quality of care received over the course of two years by 101 diabetes patients. A logistic regression model accurately identified the quality of care for 86% of the patients. Because the model uses data derived from patients’ health insurance claims it can be used to monitor the care being received by a large patient population. One important use of the model is to identify potential candidates for case management, especially patients with complicated medical histories.
Overdiagnosis in breast cancer screening: the importance of length of observation period and lead time
Authors: Duffy Stephen W , Parmar Dharmishta 
Published: May 2013

Abstract
Background
Overdiagnosis in breast cancer screening is a controversial topic. One difficulty in estimation of overdiagnosis is the separation of overdiagnosis from lead time that is the advance in the time of diagnosis of cancers, which confers an artificial increase in incidence when a screening programme is introduced.

Methods
We postulated a female population aged 50-79 with a similar age structure and age-specific breast cancer incidence as in England and Wales before the screening programme. We then imposed a two-yearly screening programme; screening women aged 50-69, to run for twenty years, with exponentially distributed lead time with an average of 40 months in screen-detected cancers. We imposed no effect of the screening on incidence other than lead time.

Results
Comparison of age- and time-specific incidence between the screened and unscreened populations showed a major effect of lead time, which could only be adjusted for by follow-up for more than two decades and including ten years after the last screen. From lead time alone, twenty-year observation at ages 50-69 would confer an observed excess incidence of 37%. The excess would only fall below 10% with 25 years or more follow-up. For the excess to be nullified, we would require 30 year follow-up including observation up to 10 years above the upper age limit for screening.

Conclusion
Studies using shorter observation periods will overestimate overdiagnosis by inclusion of cancers diagnosed early due to lead time among the nominally overdiagnosed tumours.
CRTC2 Is Required for β-Cell Function and Proliferation
Authors: Eberhard Chandra E. , Fu Accalia , Reeks Courtney , Screaton Robert A. 
Published: May 2013

Abstract
Previous work in insulinoma cell lines has established that calcineurin plays a critical role in the activation of cAMP-responsive element binding protein (Creb), a key transcription factor required for β-cell function and survival, by dephosphorylating the Creb coactivator Creb-regulated transcription coactivator (Crtc)2 at 2 regulatory sites, Ser171 and Ser275. Here, we report that Crtc2 is essential both for glucose-stimulated insulin secretion and cell survival in the β-cell. Endogenous Crtc2 activation is achieved via increasing glucose levels to the physiological feeding range, indicating that Crtc2 is a sensor that couples ambient glucose concentrations to Creb activity in the β-cell. Immunosuppressant drugs such as cyclosporin A and tacrolimus that target the protein phosphatase calcineurin are commonly administered after organ transplantation. Chronic use is associated with reduced insulin secretion and new onset diabetes, suggestive of pancreatic β-cell dysfunction. Importantly, we show that overexpression of a Crtc2 mutant rendered constitutively active by introduction of nonphosphorylatable alanine residues at Ser171 and Ser275 permits Creb target gene activation under conditions when calcineurin is inhibited. Taken together, these data suggest that promoting Crtc2-Creb activity is required for β-cell function and proliferation and promoting this pathway could ameliorate symptoms of new onset diabetes after transplantation.
Atomic-modeling and Simulation of Copper Sulfide as Micro Solid Lubricant
Authors: Sato Tomohiro , Hirai Yoshimasa , Fukui Takehisa , Ejima Takahiro , Takuma Masanori , Saitoh Ken-ichi 
Published: May 2013

ABSTRACTMany industries have developed new materials as substitutes for lead in solid lubricants. For example, lead bronze, a Cu-Pb alloy that has been used for slide bearings, has been replaced by a Cu alloy containing sulfide. The development of Pb-free Cu alloys has received considerable attention recently. Pb and sulfide are types of solid lubricants; in particular, MoS2 (molybdenum disulfide) is a popular sulfide lubricant. This study focuses on a material that contains Cu2S. The properties of Cu2S as a solid lubricant are unknown. First principles (FP) and molecular dynamics (MD) are used to clarify the lubrication mechanism of Cu2S. The atomiclevel stable structure of Cu2S is evaluated by FP under specific sliding conditions. The Cu2S lubrication mechanism is clarified by MD using the FP results for the interatomic potential functions. It is clarified that there is a specific slip system and the Cu-S bonds that exists above and below the layers of the slip system are very strong.
Polycaprolactone-Hydroxyapatite Composite Membrane Scaffolds for Bone Tissue Engineering
Authors: Morelli Sabrina , Facciolo Daniele , Messina Antonietta , Piscioneri Antonella , Salerno Simona , Drioli Enrico , De Bartolo Loredana 
Published: May 2013

ABSTRACTBone tissue engineering typically involves the use of porous, bioresorbable scaffolds to serve as temporary, three-dimensional scaffolds to guide cell attachment, differentiation, proliferation, and subsequent tissue regeneration. In this study we developed a composite membrane scaffold by phase inversion technique by using biodegradable polyester, Polycaprolactone (PCL), with hydroxyapatite (HA) in order to develop novel controlled nanostructured biomaterials for bone tissue engineering applications.After preparation, membrane scaffolds were characterized in order to evaluate its morphological, physico-chemical and mechanical properties and then used for the cell culture.Our experimental design consists to apply the knowledge of natural bone tissue remodelling in an in vitro membrane biohybrid system. We used human mesenchymal stem cells for culture in the membrane scaffolds inducing the differentiation in osteoblasts and human monocytes to trigger osteoclastogenesis. Osteoclastic resorption of the scaffold material would lead to subsequent induction of osteoblasts and faster bone formation with mesenchymal stem cells. Our results show that osteoblasts and osteoclasts were successfully differentiated in the developed PCL-HA membrane scaffold. This membrane system will lead to insights in the creation of a controllable osteoinductive microenvironment based on the specific properties (e.g. basic composition, surface chemistry, architecture) and on the function (resorption coupled to proliferation and differentiation) of defined cellular systems.
Methodology for Combined Neutron Diffraction and Bragg Edge Imaging
Authors: Woracek R. , Bunn J.R. , Penumadu D. , Tremsin A. , Siriruk A. , Kardjilov N. , Manke I. , Boin M. , Hilger A. , Hubbard C.R. , Clausen B. , Sisneros T.A. 
Published: May 2013

ABSTRACTSimultaneous use of neutron diffraction and attenuation based transmission Bragg edge imaging for strain measurements is demonstrated in this paper using the pulse neutron source at Los Alamos National Laboratory. Cylindrical samples made from ferritic steel have been subjected to in-situ elastic loading in tension and torsion. Lattice strains were investigated for both deformation modes by time-of-flight (TOF) neutron diffraction using two detector banks at 2θ of ±90°. At the same time, the transmitted portion of the neutron beam was recorded with the goal to analyze the position and shape of the Bragg edges, using a novel time/energy resolved Microchannel Plate (MCP) detector with pixel size of 55 µm and a 28x28 mm2 field of view. Lattice strains obtained using neutron diffraction indicate that the deformation path (tension versus torsion) has important effect on their evolution and related results are summarized.The emphasis of this paper is to explain the aspects of the experimental setup and data interpretation associated with neutron Bragg edge transmission technique for obtaining through-thickness averaged strain measurements. Implications of using transmission imaging based strain mapping for samples subjected to deformation under tensile loading (where stress at a given cross-section is constant) versus torsional loading (where stress varies linearly from center to outer radius) are discussed. In the case of samples subjected to tensile loading, analysis of the Bragg edge shifts provides the strain value in the direction of the transmitted beam. Thus, three strain components are measured simultaneously when performing Bragg edge imaging in addition to diffraction using two detector banks. For specimens subjected to pure shear by torsion, the Bragg edge transmission technique cannot readily provide quantitative strain information as the mid-point of the Bragg edge does not shift uniformly due to external loading, but results in a broadening of the Bragg edge. Such information can be used to describe the variation of strain distribution along the transmitted beam direction. Spatially resolved Bragg edge maps will be very helpful to detect d-spacing inhomogeneities within the illuminated volume, which may remain undetected when using diffraction only measurements.
Nucleation and growth of CdS nanoparticles observed by ultrafast SAXS
Authors: Schiener A. , Wlochowitz T. , Gerth S. , Unruh T. , Rempel A. , Amenitsch H. , Magerl A. 
Published: May 2013

ABSTRACTAqueous solutions containing Cd2+ and S2- ions have been brought together in a T-mixer, and the formation of CdS nanoparticles has been monitored by ultrafast X-ray small angle scattering down to 0.2 ms. While no particle formation is observed for a laminar flow, their growth can be followed in-situ for conditions of turbulent flow.
Impact of Gate Metal on Surface States Distribution and Effective Surface Barrier Height in AlGaN/GaN Heterostructures
Authors: Goyal Nitin , Fjeldly Tor A. 
Published: May 2013

ABSTRACTA physics based model is presented to describe the surface donor density distribution for metal/AlGaN/GaN structures. This model partly relies on experimental observations to describe the reduction that takes place in surface donor density when the metal gate is deposited. This new model is based on our previous work on the bare surface barrier height for both unrelaxed and partially relaxed barrier layers. The model predictions are consistent with reported experimental data.
Factors Explaining Racial/Ethnic Disparities in Rates of Physician Recommendation for Colorectal Cancer Screening
Authors: Ahmed Nasar U. , Pelletier Valerie , Winter Kelly , Albatineh Ahmed N. 
Published: May 2013

Objectives. Physician recommendation plays a crucial role in receiving endoscopic screening for colorectal cancer (CRC). This study explored factors associated with racial/ethnic differences in rates of screening recommendation.Methods. Data on 5900 adults eligible for endoscopic screening were obtained from the National Health Interview Survey. Odds ratios of receiving an endoscopy recommendation were calculated for selected variables. Planned, sequenced logistic regressions were conducted to examine the extent to which socioeconomic and health care variables account for racial/ethnic disparities in recommendation rates.Results. Differential rates were observed for CRC screening and screening recommendations among racial/ethnic groups. Compared with Whites, Hispanics were 34% less likely (P < .01) and Blacks were 26% less likely (P < .05) to receive this recommendation. The main predictors that emerged in sequenced analysis were education for Hispanics and Blacks and income for Blacks. After accounting for the effects of usual source of care, insurance coverage, and education, the disparity reduced and became statistically insignificant.Conclusions. Socioeconomic status and access to health care may explain major racial/ethnic disparities in CRC screening recommendation rates.
Bicycle Guidelines and Crash Rates on Cycle Tracks in the United States
Authors: Lusk Anne C. , Morency Patrick , Miranda-Moreno Luis F. , Willett Walter C. , Dennerlein Jack T. 
Published: May 2013

Objectives. We studied state-adopted bicycle guidelines to determine whether cycle tracks (physically separated, bicycle-exclusive paths adjacent to sidewalks) were recommended, whether they were built, and their crash rate. Methods. We analyzed and compared US bicycle facility guidelines published between 1972 and 1999. We identified 19 cycle tracks in the United States and collected extensive data on cycle track design, usage, and crash history from local communities. We used bicycle counts and crash data to estimate crash rates. Results. A bicycle facility guideline written in 1972 endorsed cycle tracks but American Association of State Highway and Transportation Officials (AASHTO) guidelines (1974–1999) discouraged or did not include cycle tracks and did not cite research about crash rates on cycle tracks. For the 19 US cycle tracks we examined, the overall crash rate was 2.3 (95% confidence interval = 1.7, 3.0) per 1 million bicycle kilometers. Conclusions. AASHTO bicycle guidelines are not explicitly based on rigorous or up-to-date research. Our results show that the risk of bicycle–vehicle crashes is lower on US cycle tracks than published crashes rates on roadways. This study and previous investigations support building cycle tracks.
Public Health and Law Collaboration: The Philadelphia Lead Court Study
Authors: Campbell Carla , Gracely Ed , Pan Sarah , Cummings Curtis , Palermo Peter , Gould George 
Published: May 2013

Objectives. We determined whether Philadelphia Lead Court is effective in enforcing lead hazard remediation in the homes of children with elevated blood lead levels. Methods. We created a deidentified data set for properties with an initial failed home inspection (IFHI) for lead hazards from January 1, 1998, through December 31, 2008, and compared compliance rates within the first year and time to compliance for lead hazard remediation between 1998 and 2002 (precourt period) and between 2003 and 2008 (court period). We evaluated predictors of time to compliance. Results. Within 1 year of the IFHI, 6.6% of the precourt and 76.8% of the court cases achieved compliance (P < .001) for the 3764 homes with data. Four years after the IFHI, 18% had attained compliance in the precourt period compared with 83.1% for the court period (P < .001). A proportional hazard analysis found that compliance was 8 times more likely in the court than the precourt period (P < .001). Conclusions. Lead court was more effective than precourt enforcement strategies. Most properties were remediated within 1 year of the IFHI, and time to compliance was significantly reduced. This model court could be replicated in other cities with similar enforcement problems.
Increasing Children’s Physical Activity During School Recess Periods
Authors: Chin John J. , Ludwig David 
Published: May 2013

Objectives. We examined whether schools’ participation in the Recess Enhancement Program (REP) in the spring of 2011 was associated with higher rates of children’s vigorous physical activity. Methods. In REP, a coach guides children through age-appropriate games aimed at increasing their physical activity. During recess at 25 New York City public elementary schools (15 REP, 10 non-REP), researchers visually scanned predetermined areas (n = 1339 scans), recording the number of sedentary, walking, and very active children. Results. Multivariate statistical analysis found that participation in REP was a significant predictor (P = .027) of the rate of vigorous physical activity (percentage very active in scan area) whose least-squares means were 41% in REP schools and 27% in non-REP schools. A significantly higher rate in REP schools persisted when the coach was not in the scan area, suggesting a change in the recess culture of REP schools. Conclusions. The rate of vigorous physical activity in REP schools was 14 percentage points, or 52%, higher than the rate in non-REP schools. This low-cost intervention might be a valuable addition to the tools for combating childhood obesity and worth replicating elsewhere.
Pathways to Early Violent Death: The Voices of Serious Violent Youth Offenders
Authors: Richardson Joseph B. , Brown Jerry , Van Brakle Michelle 
Published: May 2013

Quantitative studies have uncovered factors associated with early violent death among youth offenders detained in the juvenile justice system, but little is known about the contextual factors associated with pathways to early violent death among youths detained in adult jails. We interviewed young Black male serious violent youth offenders detained in an adult jail to understand their experience of violence. Their narratives reveal how the code of the street, informal rules that govern interpersonal violence among poor inner-city Black male youths, increases the likelihood of violent victimization. Youth offenders detained in adult jails have the lowest rate of service provision among all jail populations. We have addressed how services for youth offenders can be improved to reduce the pathways to early violent death.
Creating Smoke-Free Places Through the UN Convention on the Rights of Persons With Disabilities
Authors: Rutkow Lainie , Vernick Jon S. , Tung Gregory J. , Cohen Joanna E. 
Published: May 2013

In some high-, middle-, and low-income countries, law has been employed to limit individuals’ secondhand smoke exposure. Innovative legal tools are still needed, especially in low- and middle-income countries where smoking prevalence continues to rise. For some persons with severe respiratory conditions, the presence of secondhand smoke is intolerable and prevents their entrance into restaurants and other venues. With its adoption of the Convention on the Rights of Persons with Disabilities (CRPD) in 2006, the United Nations gave countries a new way to promote the rights of disabled individuals and simultaneously address secondhand smoke exposure. We analyze the CRPD’s potential to advance tobacco control goals and offer recommendations for advocates, policymakers, and others seeking to apply this approach.