bluuebunny/crossref_metadata_2025 huggingface dataset:
Decrease in β-Cell Proliferation Precedes Apoptosis during Diabetes Development in Bio-Breeding/Worcester Rat: Beneficial Role of Exendin-4
Authors: Pérez-Arana Gonzalo , Blandino-Rosano Manuel , Prada-Oliveira Arturo , Aguilar-Diosdado Manuel , Segundo Carmen
Published: April 2010

In autoimmune type 1 diabetes mellitus, proinflammatory cytokine-mediated apoptosis of β-cells has been considered to be the first event directly responsible for β-cell mass reduction. In the Bio-Breeding (BB) rat, an in vivo model used in the study of autoimmune diabetes, β-cell apoptosis is observed from 9 wk of age and takes place after an insulitis period that begins at an earlier age. Previous studies by our group have shown an antiproliferative effect of proinflammatory cytokines on cultured β-cells in Wistar rats, an effect that was partially reversed by Exendin-4, an analogue of glucagon-like peptide-1. In the current study, the changes in β-cell apoptosis and proliferation during insulitis stage were also determined in pancreatic tissue sections in normal and thymectomized BB rats, as well as in Wistar rats of 5, 7, 9, and 11 wk of age. Although stable β-cell proliferation in Wistar and thymectomized BB rats was observed along the course of the study, a decrease in β-cell proliferation and β-cell mass from the age of 5 wk, and prior to the commencement of apoptosis, was noted in BB rats. Exendin-4, in combination with anti-interferon-γ antibody, induced a near-total recovery of β-cell proliferation during the initial stages of insulitis. This highlights the importance of early intervention and, as well, the possibilities of new therapeutic approaches in preventing autoimmune diabetes by acting, initially, in the insulitis stage and, subsequently, on β-cell regeneration and on β-cell apoptosis.
Sulfatase 1 Is an Inhibitor of Ductal Morphogenesis with Sexually Dimorphic Expression in the Urogenital Sinus
Authors: Buresh Rita A. , Kuslak Sheri L. , Rusch Melissa A. , Vezina Chad M. , Selleck Scott B. , Marker Paul C.
Published: April 2010

The prostate gland develops from the urogenital sinus in response to circulating androgens. Androgens initiate and stimulate branching morphogenesis in the urogenital sinus via unknown mediators. Heparan sulfate proteoglycans are important extracellular molecules that sequester many growth factors in the extracellular matrix and facilitate signaling by some growth factors as part of ternary complexes that include growth factors, receptors, and heparan sulfate chains. Several enzymes modify the chemical structure of heparan sulfate to further regulate its activity. An examination of these enzymes for sexually dimorphic expression in the urogenital sinus identified Sulfatase 1 (Sulf1) as an enzyme that was down-regulated in the male urogenital sinus coincident with the initiation of prostatic morphogenesis. Down-regulation of Sulf1 was accompanied by an increase in the most highly sulfated forms of heparan sulfate, and a similar increase was observed in female urogenital sinuses treated with testosterone. Inhibiting de novo sulfation of heparan sulfate blocked prostatic morphogenesis, supporting the importance of heparan sulfate modification for prostate development. To functionally test the specific role of Sulf1 during prostate development, Sulf1 was ectopically expressed in the urogenital sinus. It partially inhibited testosterone-stimulated ductal morphogenesis, and it reduced the activation of fibroblast growth factor receptors as well as the ERK1 and ERK2 MAPKs. These data identify sulfatase 1 as an inhibitor of prostatic branching morphogenesis and growth factor signaling that is down-regulated as part of the normal response to androgen action in the male urogenital sinus.
Intermittent Parathyroid Hormone Administration Counteracts the Adverse Effects of Glucocorticoids on Osteoblast and Osteocyte Viability, Bone Formation, and Strength in Mice
Authors: Weinstein Robert S. , Jilka Robert L. , Almeida Maria , Roberson Paula K. , Manolagas Stavros C.
Published: April 2010

Glucocorticoids act directly on bone cells to decrease production of osteoblasts and osteoclasts, increase osteoblast and osteocyte apoptosis, and prolong osteoclast life span. Conversely, daily injections of PTH decrease osteoblast and osteocyte apoptosis and increase bone formation and strength. Using a mouse model, we investigated whether the recently demonstrated efficacy of PTH in glucocorticoid-induced bone disease results from the ability of this therapeutic modality to counteract at least some of the direct effects of glucocorticoids on bone cells. Glucocorticoid administration to 5- to 6-month-old Swiss-Webster mice for 28 d increased the prevalence of osteoblast and osteocyte apoptosis and decreased osteoblast number, activation frequency, and bone formation rate, resulting in reduced osteoid, wall and trabecular width, bone mineral density, and bone strength. In contrast, daily injections of PTH caused a decrease in osteoblast and osteocyte apoptosis and an increase in osteoblast number, activation frequency, bone formation rate, bone mineral density, and bone strength. The decreased osteocyte apoptosis was associated with increased bone strength. When the two agents were combined, all the adverse effects of glucocorticoid excess on bone were prevented. Likewise, in cultured osteoblastic cells, PTH attenuated the adverse effects of glucocorticoids on osteoblast survival and Wnt signaling via an Akt phosphorylation-dependent mechanism. We conclude that intermittent PTH administration directly counteracts the key pathogenetic mechanisms of glucocorticoid excess on bone, thus providing a mechanistic explanation of its efficacy against glucocorticoid-induced osteoporosis.
High-Fat Diet Increases Thyrotropin and Oxygen Consumption without Altering Circulating 3,5,3′-Triiodothyronine (T3) and Thyroxine in Rats: The Role of Iodothyronine Deiodinases, Reverse T3 Production, and Whole-Body Fat Oxidation
Authors: Araujo R. L. , Andrade B. M. , Padrón A. S. , Gaidhu M. P. , Perry R. L. S. , Carvalho D. P. , Ceddia R. B.
Published: April 2010

This study investigated the effects of obesity induced by high-fat (HF) diet on thyroid function and whole-body energy balance. To accomplish that, we assessed the effects of 8 wk of HF diet on several parameters of hypothalamus-pituitary-thyroid axis function. Serum total T4 and T3, rT3, and TSH, the activity of type 1 and type 2 deiodinases in central and peripheral tissues were determined. Also, we measured in vivo energy balance, substrate partitioning, and markers of leptin resistance. Here we provide novel evidence that prolonged positive energy balance acquired by feeding a HF diet induced hyperactivation of the hypothalamus-pituitary-thyroid axis, which was characterized by 2.24-, 1.6-, and 3.7-fold elevations in hypothalamic TRH expression, thyroid iodide uptake, and serum TSH, respectively. Serum T4 and T3 were normal together with augmented deiodinase type 1 activity in liver (1.3-fold) and kidney (1.2-fold) and increased (1.5-fold) serum rT3 in HF rats. Despite no increase in circulating levels of T3 and T4, whole-body oxygen consumption was increased, and substrate metabolism was shifted toward fat oxidation in HF rats. These in vivo metabolic adjustments were mainly driven by the fat content of the diet. Furthermore, spontaneous dark cycle physical activity was reduced by 30% in rats fed a HF diet, which limited energy expenditure and favored the development of obesity. Our findings provide new insight into the endocrine and physiological mechanisms that underlie the alterations in thyroid hormone availability, energy balance, and metabolic partitioning in HF diet-induced obesity.
Deoxyribonucleic Acid Methylation and Gene Expression of PPARGC1A in Human Muscle Is Influenced by High-Fat Overfeeding in a Birth-Weight-Dependent Manner
Authors: Brøns Charlotte , Jacobsen Stine , Nilsson Emma , Rönn Tina , Jensen Christine B. , Storgaard Heidi , Poulsen Pernille , Groop Leif , Ling Charlotte , Astrup Arne , Vaag Allan
Published: April 2010

Context: Low birth weight (LBW) and unhealthy diets are risk factors of metabolic disease including type 2 diabetes (T2D). Genetic, nongenetic, and epigenetic data propose a role of the key metabolic regulator peroxisome proliferator-activated receptor γ, coactivator 1α (PPARGC1A) in the development of T2D.

Objective: Our objective was to investigate gene expression and DNA methylation of PPARGC1A and coregulated oxidative phosphorylation (OXPHOS) genes in LBW and normal birth weight (NBW) subjects during control and high-fat diets.

Design, Subjects, and Main Outcome Measures: Twenty young healthy men with LBW and 26 matched NBW controls were studied after 5 d high-fat overfeeding (+50% calories) and after a control diet in a randomized manner. Hyperinsulinemic-euglycemic clamps were performed and skeletal muscle biopsies excised. DNA methylation and gene expression were measured using bisulfite sequencing and quantitative real-time PCR, respectively.

Results: When challenged with high-fat overfeeding, LBW subjects developed peripheral insulin resistance and reduced PPARGC1A and OXPHOS (P < 0.05) gene expression. PPARGC1A methylation was significantly higher in LBW subjects (P = 0.0002) during the control diet. However, PPARGC1A methylation increased in only NBW subjects after overfeeding in a reversible manner. DNA methylation of PPARGC1A did not correlate with mRNA expression.

Conclusions: LBW subjects developed peripheral insulin resistance and decreased gene expression of PPARGC1A and OXPHOS genes when challenged with fat overfeeding. The extent to which our finding of a constitutively increased DNA methylation in the PPARGC1A promoter in LBW subjects may contribute needs to be determined. We provide the first experimental support in humans that DNA methylation induced by overfeeding is reversible.
Simultaneous determination of multiple mRNA levels utilizing MALDI-TOF mass spectrometry and biotinylated dideoxynucleotides
Authors: Duffield Daniel Scott , Cai Li , Kim Sobin
Published: April 2010

Here we report an efficient method to simultaneously measure multiple mRNA levels utilizing mass spectrometry (MS) and molecular affinity isolation. In this approach, reverse transcription products of a group of mRNAs are subjected to competitive PCR with competitors and internal standards of known concentrations, and the PCR products are differentiated and quantified by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS to determine the mRNA levels. The method provides high accuracy in quantitative MS analysis due to the facilitated purification of oligonucleotides by molecular affinity isolation. Additionally, owing to the molecular affinity isolation, only those oligonucleotides required for expression level determination are introduced into the mass spectrometer, while other irrelevant reaction components that could overlap with peaks of gene transcripts or competitors are removed prior to MS analysis. Thus the approach enhances the parallel analysis of multiple gene transcripts by MS. Utilizing the method we have simultaneously measured mRNA levels of four genes (Rho, Nrl, Hprt, and Lhx2) in mouse retinal tissue.
Identification and characterization of anion binding sites in RNA
Authors: Kieft Jeffrey S. , Chase Elaine , Costantino David A. , Golden Barbara L.
Published: April 2010

Although RNA molecules are highly negatively charged, anions have been observed bound to RNA in crystal structures. It has been proposed that anion binding sites found within isolated RNAs represent regions of the molecule that could be involved in intermolecular interactions, indicating potential contact points for negatively charged amino acids from proteins or phosphate groups from an RNA. Several types of anion binding sites have been cataloged based on available structures. However, currently there is no method for unambiguously assigning anions to crystallographic electron density, and this has precluded more detailed analysis of RNA–anion interaction motifs and their significance. We therefore soaked selenate into two different types of RNA crystals and used the anomalous signal from these anions to identify binding sites in these RNA molecules unambiguously. Examination of these sites and comparison with other suspected anion binding sites reveals features of anion binding motifs, and shows that selenate may be a useful tool for studying RNA–anion interactions.
High-power impulse magnetron sputtering and its applications
Authors: Ehiasarian Arutiun P.
Published: April 2010

High-power impulse magnetron sputtering (HIPIMS) was introduced in the late 1990s as a unique physical vapor deposition method. The technology utilizes magnetron sputtering cathodes and high peak power density of up to 3 kW cm–2 on the target. The plasma produces a metal flux with high degree of ionization. HIPIMS has been successfully used as a substrate pretreatment method to enhance coating adhesion by promoting local epitaxial growth. As a deposition technology, HIPIMS produces high-density microstructure films. It has been industrialized and has successful applications in hard, electronic, and optical coatings.
Sources of inspiration: How design students learn from museum collections and other sources of inspiration
Authors: Reading Christina
Published: April 2010

We need a clearer picture of the ways in which students learn from museum collections and other sources of inspiration. Taking a phenomenographic approach this research suggests ways in which students learn from the collections, and argues that some students, lacking the motivation
and skills they need to enable them to get the best out of this important resource, find their engagement with museums challenging. The research concludes that Higher Education (HE) and museums will need to work collaboratively to champion measures to reinvigorate learning from these sources.
Intersections: The utility of an Assessment for Learning discourse for Design educators
Authors: Bohemia Erik , Harman Kerry , McDowell Liz
Published: April 2010

This paper explores the productiveness of the intersecting knowledge domains of Teaching and Learning and Design. More specifically it examines the utility of an Assessment for Learning (AfL) framework developed by researchers at the Centre for Excellence in Teaching and Learning (CETL)
at Northumbria University for articulating the curriculum design, delivery and assessment strategies employed in the Global Studio a design module conducted at a UK university. Using a case study methodology with the aim of compiling rich, practice-based knowledge (Denzin and Lincoln 2005),
we draw on data gathered throughout the development and delivery of the Global Studio in order to undertake our analysis. We suggest that many Assessment for Learning elements were implicitly embedded in this module. We propose that Assessment for Learning may provide a useful conceptual frame
for exploring pedagogical practices and student learning experiences more generally in the design studio.
The design and development of Genarrator at Bournemouth University
Authors: Pope James
Published: April 2010

Genarrator is a practice-based and pedagogy-driven project researching ways of enabling creative writers and designers to enter the world of interactive fiction. The overall aim of the project is to develop a software platform (also calledGenarrator) for students who want to create interactive digital fiction, but who do not have the web-design skills to use professional-level tools such as Flash. Funded by The Centre for Excellence in Media Practice (CEMP) at BU, James Pope is extending his empirical studies of readers' responses to interactive fiction, and expanding his teaching of new-media writing, by designing, developing and testingGenarrator. This paper reports on the empirical research which has led toGenarrator, outlines the role of the CETL in supporting the project, and explains the features and value of theGenarratorplatform.
Threshold concepts and the transport and product design curriculum: reports of research in progress
Authors: Osmond Jane , Bull Karen , Tovey Mike
Published: April 2010

In 2005, Coventry University was successful in bidding for Centre of Excellence in Teaching and Learning (CETL) funding from HEFCE, which led to the creation of the Centre of Excellence for Product and Automotive Design (CEPAD).

This article discusses pedagogic research carried out
by CEPAD to date, with a particular focus on the journey towards identifying one particular threshold concept in student transport and product design education. It also explores preliminary thoughts on how this identification of hitherto tacit knowledge can feed into the design thinking and
solutioning process. From this, the article offers some implications for the enhancement of teaching and learning within the design curriculum.
Determining the Oxidation Stability of Biodiesel and Blends Using a New Rapid Small Scale Oxidation Test (RSSOT)—The PetroOXY
Authors: Wierzbicki Volkmar
Published: April 2010

Oxidation stability is a physical property of liquid fuels used to describe the ageing behavior of fuels during transport and storage. In biodiesel and its blends with diesel, oxidation of fuel can result in acid formation and polymer solids which plug filters and leave problematic deposits throughout the fuel supply system. ASTM Fuel Specification Standards include both 100 % biodiesel and biofuel-blends. Of all these fuel standards only ASTM D6751, which is for 100 % biodiesel “as a blendstock,” mentions the test method EN 14112. Although the following fuel specification standards permit the blending of biodiesel into the fuel, to date these standards have not yet identified a suitable oxidation stability test method for blended fuels: ASTM D975 for diesel fuel oils (<5 % biodiesel); ASTM D396 for burner fuel oils (<5 % biodiesel); and ASTM D7467 for diesel fuel oil (6–20 % biodiesel). ASTM D2274 is the most frequently used method to characterize ageing behavior of diesel by determining the polymer (sludge) content of artificially aged fuel. ASTM D02.14 approved two new test methods for evaluation of oxidation stability. ASTM D7545 is a new method for testing oxidation stability of middle-distillates. ASTM D7525 is the sister method for gasoline. These methods utilize a new rapid small scale oxidation tester (RSSOT) named PetroOXY. Within the RSSOT’s test chamber, a 5 mL sample of fuel is combined with oxygen, at 700 kPa, and heated to 140°C. This initiates a fast oxidation whose results are determined by the time needed to achieve a pressure drop of 10 % in the system. Testing confirmed that the time needed to achieve the 10 % drop in pressure is directly related to the sample’s oxidation stability. The RSSOT-method is quicker than other actual methods evaluating the oxidation stability biodiesel, petroleum middle-distillates, and blends. Round-robins based upon this have been conducted in Europe and Japan.
The Application of Various Indicators for the Estimation of Carbonation and pH of Cement Based Materials
Authors: Yu Myoung-Youl , Lee Jae-Yong , Chung Chul-Woo
Published: April 2010

Carbonation decreases the pH of the concrete and breaks the passivity of reinforcing steel. Therefore, carbonation is related to potential rebar corrosion even though carbonation itself does not directly damage the integrity of the concrete. The phenolphthalein method, which is the most often used method of determining carbonation, however, has a reliability problem. Therefore, this research mainly focuses on the use of various indicators to find the possible substitutes for phenolphthalein. The early carbonation and pH of the carbonated specimen was also investigated using various indicators. It was found from the results that thymolphthalein was the best substitute for phenolphthalein, and a combination of phenolphthalein and thymolphthalein, tropaeolin O, and indigo carmine enabled us to estimate the early carbonation. This research also reported the successful application of various indicators which can be extended for the pH estimation of solid mortar specimen.
Coefficients of Thermal Expansion of Concrete with Different Coarse Aggregates–Texas Data
Authors: Lukefahr Elizabeth , Du Lianxiang
Published: April 2010

The first section of this paper summarizes the efforts of Texas Department of Transportation (TxDOT) to evaluate the coefficients of thermal expansion (COTEs) of a total of 93 concrete mixtures, of which the only difference is the coarse aggregate incorporated. The mean COTE value of siliceous gravel concrete is about 30 % higher than that of limestone concrete. The data in Texas shows that the upper 50 % COTE values of limestone concrete overlaps the lower 20 % COTE values of siliceous gravel concrete. The results strongly suggest that pre-qualification of coarse aggregate for typical paving concrete in aspect to COTE should be considered. A model by Emanuel and Hulsey is used to back calculate COTE of coarse aggregate. The second section of this article compares the COTE data set on existing pavement measured by Federal Highway Administration with those obtained at TxDOT concrete laboratory.
Novel therapeutic possibilities in systemic lupus erythematosus
Authors: Bazsó Anna , Poór Gyula , Gergely Péter , Kiss Emese
Published: April 2010

A szisztémás lupus erythematosus (SLE) autoimmun betegség, amely számos szervet és szervrendszert érint. Ennek következtében változatos klinikai tünetek és jellegzetes szerológiai eltérések jelennek meg. Annak ellenére, hogy a túlélés SLE-ben jelentősen javult az elmúlt évtizedek folyamán, a betegek körülbelül 10-20%-a nem reagál a hagyományos immunszuppresszív kezelések egyikére sem. A recidíva ennél is gyakoribb; diffúz proliferatív nephritisben ciklofoszfamidkezelést követően 30% körüli. A betegség patomechanizmusában különböző immunkompetens sejtek és gyulladásos mediátorok vesznek részt. Involvált mind az adaptív, mind a természetes immunitás. Ebből kifolyólag számos patogén alkotóelem és mechanizmus lehet terápiás beavatkozás célpontja. Jelen munkában a szerzők az SLE patogenezisének aspektusából ismertetik az ígéretesnek tűnő terápiás lehetőségeket és azok mechanizmusát. Áttekintik a T- és B-sejtek, a kostimulációs útvonalak, a citokinhálózat és a szolúbilis mediátorok befolyásolásának lehetőségeit, valamint az autológ haemopoeticus őssejt-transzplantáció jelenlegi állását.
Learning About Mason: A Collaborative Lesson With a Struggling Reader
Authors: Compton‐Lilly Catherine
Published: April 2010

In this Struggling Readers department, the author describes the collaborative lesson—a professional development strategy adapted from Reading Recovery. Collaborative lessons involve a small group of educators who collaborate to help a student who is struggling with reading. While collaborative lessons were initially designed by Reading Recovery professionals, they can be implemented with any struggling reader.

في قسم القراء المواجهين صعوبات في القراءة هذا، يصف المؤلف الدرس المتعاون—إستراتيجية تنمية حرفة مقتبسة من برنامج استعادة القراءة. وتضم الدروس المتعاونة مجموعة من المعلمين الذين يتعاونون لمساعدة طالب يواجه صعوبة في القراءة. ومع أن الدروس المتعاونة كانت مصممة أولاً على أيدي محترفي استعادة القراءة فإنها قد تنفذ مع أي قارئ مواجه صعوبة في القراءة.

作者在这个「有阅读困难的阅读者」的部门中描述一项协作教学，该项协作教学是改编自《恢复阅读能力教学方案》的一个专业培训策略。该协作教学课堂是由一小组的教育工作者协同帮助一名有阅读困难的学生。该协作教学课堂最初是由《恢复阅读能力教学方案》的专业人员设计，可以施教给任何有阅读困难的阅读者。

Dans cette rubrique Lecteurs en difficulté, présente la leçon en coopération — une stratégie de développement professionnel adaptée de Récupération de la lecture. Les leçons en coopération comportent un petit groupe de pédagogues qui coopèrent pour aider un élève en difficulté en lecture. Bien que les leçons en coopération ont été conçues à l'origine par des professionnels de Récupération de la lecture, il est possible de les mettre en place pour n'importe quel lecteur en difficulté.

В этом выпуске рубрики, посвященной проблемам детей, которым чтение дается нелегко, автор описывает “урок сотрудничества” – стратегию, взятую из программы “Возрождение чтения” (BP). На уроках сотрудничества небольшая группа педагогов объединяется для помощи слабо читающим ученикам. Изначально в этом формате имели право работать только профессионалы, прошедшие обучение по программе BP, но теперь эти методы адаптированы и их могут применять все учителя, работающие со слабо читающими школьниками.

En esta sección de Lectores con Dificultades, el autor describe la lección de colaboración—una estrategia de desarrollo profesional adaptada de Reading Recovery. Las lecciones de colaboración envuelven a un pequeño grupo de profesores que colaboran para ayudar al estudiante que tiene dificultades con la lectura. Aunque las lecciones de colaboración fueron diseñadas originalmente por profesionales de Reading Recovery, funcionan con cualquier lector con dificultades.
Targeting the TGF-β1 Pathway to Prevent Normal Tissue Injury After Cancer Therapy
Authors: Anscher Mitchell S.
Published: April 2010

With >10,000,000 cancer survivors in the U.S. alone, the late effects of cancer treatment are a significant public health issue. Over the past 15 years, much work has been done that has led to an improvement in our understanding of the molecular mechanisms underlying the development of normal tissue injury after cancer therapy. In many cases, these injuries are characterized at the histologic level by loss of parenchymal cells, excessive fibrosis, and tissue atrophy. Among the many cytokines involved in this process, transforming growth factor (TGF)-β1 is thought to play a pivotal role. TGF-β1 has a multitude of functions, including both promoting the formation and inhibiting the breakdown of connective tissue. It also inhibits epithelial cell proliferation. TGF-β1 is overexpressed at sites of injury after radiation and chemotherapy. Thus, TGF-β1 represents a logical target for molecular therapies designed to prevent or reduce normal tissue injury after cancer therapy. Herein, the evidence supporting the critical role of TGF-ß1 in the development of normal tissue injury after cancer therapy is reviewed and the results of recent research aimed at preventing normal tissue injury by targeting the TGF-ß1 pathway are presented.
Imaging in Radiation Oncology: A Perspective
Authors: Dawson Laura A. , Ménard Cynthia
Published: April 2010

An inherent goal of radiation therapy is to deliver enough dose to the tumor to eradicate all cancer cells or to palliate symptoms, while avoiding normal tissue injury. Imaging for cancer diagnosis, staging, treatment planning, and radiation targeting has been integrated in various ways to improve the chance of this occurring. A large spectrum of imaging strategies and technologies has evolved in parallel to advances in radiation delivery. The types of imaging can be categorized into offline imaging (outside the treatment room) and online imaging (inside the treatment room, conventionally termed image-guided radiation therapy). The direct integration of images in the radiotherapy planning process (physically or computationally) often entails trade-offs in imaging performance. Although such compromises may be acceptable given specific clinical objectives, general requirements for imaging performance are expected to increase as paradigms for radiation delivery evolve to address underlying biology and adapt to radiation responses. This paper reviews the integration of imaging and radiation oncology, and discusses challenges and opportunities for improving the practice of radiation oncology with imaging.
Gemcitabine plus metronomic 5-fluorouracil or capecitabine as a second-/third-line chemotherapy in advanced adrenocortical carcinoma: a multicenter phase II study
Authors: Sperone Paola , Ferrero Anna , Daffara Fulvia , Priola Adriano , Zaggia Barbara , Volante Marco , Santini Daniele , Vincenzi Bruno , Badalamenti Giuseppe , Intrivici Chiara , Del Buono Sabrina , De Francia Silvia , Kalomirakis Emmanouil , Ratti Riccardo , Angeli Alberto , Dogliotti Luigi , Papotti Mauro , Terzolo Massimo , Berruti Alfredo
Published: April 2010

Adrenocortical carcinoma (ACC) is a rare neoplasm characterized by poor prognosis. First-line systemic treatments in advanced disease include mitotane, either alone or in combination with chemotherapy. Studies evaluating second-line therapy options have obtained disappointing results. This trial assessed the activity and toxicity of gemcitabine plus metronomic fluoropyrimidines in heavily pretreated advanced ACC patients. From 1998 to 2008, 28 patients with advanced ACC progressing after mitotane plus one or two systemic chemotherapy lines were enrolled. They received a combination of i.v. gemcitabine (800 mg/m2, on days 1 and 8, every 21 days) and i.v. 5-fluorouracil protracted infusion (200 mg/m2/daily without interruption until progression) in the first six patients, or oral capecitabine (1500 mg/daily) in the subsequent patients. Mitotane administration was maintained in all cases. The rate of non-progressing patients after 4 months of treatment was 46.3%. A complete response was observed in 1 patient (3.5%); 1 patient (3.5%) obtained a partial regression, 11 patients (39.3%) obtained a disease stabilization and 15 patients (53.7%) progressed. Treatment was well tolerated, with grade III and IV toxicities consisting of leukopenia in six patients (21.4%), thrombocytopenia in one patient (3.5%), and mucositis in one patient (3.5%). Median time to progression and overall survival in the patient population were 5.3 (range: 1–43) and 9.8 months (range: 3–73) respectively. Gemcitabine plus metronomic fluoropyrimidines is a well-tolerated and moderately active regimen in heavily pretreated ACC patients.
Evaluation of leakage of fast setting cements used to restore teeth
Authors: Camilleri J.
Published: April 2010

The aim of the present study was to evaluate the marginal adaptation and material porosity to micro-organisms of prototype restorative dental materials using two microscopy techniques. Three fast-setting cements based on Portland cement, two cement composites and a dental material were used to restore human extracted teeth. The leakage to micro-organisms was evaluated by assessing leakage to dyes using both confocal and environmental electron microscope after immersion in rhodamine B dye for 24 h and longitudinal splitting of the tooth. The use of dye simulated the leakage of the system to micro-organisms present in the human mouth. The cements showed material porosity but no leakage was observed at the tooth cavity margins. The cement composites were more stable with less dye taken up by the material in comparison with the respective neat cement. Restorations made up of the dental material showed marginal leakage along their walls and along the restoration floor. The prototype cements showed a susceptibility to take up dye through the material rather than at the tooth to material interface. The dental material exhibited mostly marginal leakage. The expansive cement showed the highest amount of leakage. The two methods of evaluation showed contrasting results mostly evident when testing the dental cement.
Effect of chromium addition on the kinetics of hydration of dicalcium silicate phase
Authors: Parkash R. , Mehta S.K. , Dixit S. , Singh S. , Ahluwalia S.C. , Sharma J.M.
Published: April 2010

Samples of dicalcium silicate (C2H) using different precursors and 0·5 to 5·0% chromium oxide (Cr2O3) were prepared and hydrated in order to study the effect of different concentrations of chromium oxide on the kinetics of hydration of the pure and doped dicalcium silicate (C2S) phase. Hydrated samples of different age intervals up to 180 days were investigated by differential thermal analysis/thermo gravimetric analysis, X-ray diffraction and scanning electron microscopic techniques. In chromium oxide-doped dicalcium silicate phase, the hydration increased with the amount of chromium oxide was increased from 0·5 to 0·7% and then declined to become minimal at 5·0% chromium oxide concentration. The degree of hydration and extent of hydration uniformly increased as the concentration of the dopant was increased from zero to 0·7%.
Effect of steel corrosion pattern on RC beam performance
Authors: Zhang R. J. , Castel A. , François R.
Published: April 2010

Chloride-induced corrosion in reinforced concrete leads to a reduction of the steel cross-section and deterioration of the steel–concrete bond. In this paper, experimental results are presented in order to clarify the respective influence of these degradations on beam serviceability (deflection). Pitting corrosion simulations were performed and two naturally corroded beams (14 and 23 years old) were analysed. Corrosion simulations have shown that the reduction in steel cross-section due to local pitting corrosion does not affect serviceability. Increased deflection is due to deterioration of the steel-concrete bond (reduction of concrete tension stiffening). Experimental results obtained on two corroded beams broken and analysed after 14 years and 23 years of chloride exposure showed that, during the natural chloride-induced corrosion process, the corrosion pattern evolves in relation to the corrosion cracking. Localised pitting corrosion is responsible for the initiation of corrosion cracking. Then, as the width of the cracks develops, general corrosion becomes gradually the main corrosion pattern. According to these experimental results, a mechanical model is proposed for serviceability assessment, which takes into account the evolution of the corrosion pattern from local pitting corrosion to general reinforcement corrosion.
Assessing Gender Differences and Co-Offending Patterns of a Predominantly “Male-Oriented” Crime: A Comparison of a Cross-National Sample of Juvenile Boys and Girls Arrested for a Sexual Offense
Authors: Vandiver Donna M.
Published: April 2010

This study examines male–female differences of juveniles arrested for a sex offense. A cross-national sample of juvenile boys (n = 177) and a population of juvenile girls (n = 177) arrested for a sex offense are utilized for this analysis. It is hypothesized that (1) boys and girls differ substantially in their offending patterns. Based on Moffitt’s social-amplification hypothesis, it is also hypothesized that (2) juveniles who act with a co-offender commit more serious offenses (i.e., more likely to be arrested for rape and have more victims) compared to those who act alone. The results show boys differ from girls: juvenile girls are slightly younger, more likely to be White, more likely to have a co-offender, less likely to commit rape, and be processed formally by law enforcement. The results yielded indicated social amplification appears to occur when girls offend with a co-offender, but not when boys acted with a co-offender.
Organic‐Horizon Lead, Copper, and Zinc Contents of Mid‐Atlantic Forest Soils, 1978–2004
Authors: Johnson A. H. , Richter S. L.
Published: April 2010

Organic soil horizona were important sinks for atmospherically delivered Pb, Cu, and Zn throughout the latter part of the 20th century. By measuring the organic matter content and the concentrations and amounts of Pb, Cu, and Zn at 28 sites that had not been disturbed by fire or human activity between 1978 and 2004, we repeated a previous study of forest floor metal content in West Virginia, Maryland, Pennsylvania, New Jersey, New York, and Connecticut. Organic matter mass increased (P < 0.05) at many sites, but when all sites are pooled, there was not a statistically significant change. Lead concentration and mass in the forest floor decreased (P < 0.05) at nearly all sites, with median changes of −65 and −57%, respectively. The decrease in Pb amount was significantly correlated with O horizon thickness, suggesting that as litter, largely free of Pb, was added at the surface, the Pb added to the forest floor during the 20th century was migrating downward into the mineral soil. In 2004, Cu and Zn concentrations and amounts were dramatically lower at sites near point sources that had ceased operating in the 1970s or 1980s, and they decreased (P < 0.05) across the region. By 2004, nearly all of the sites had forest floor Pb, Cu, and Zn concentrations well below the levels associated with adverse effects on microbial respiration, suggesting that these metals are not altering forest floor decomposition or nutrient cycling rates.
Denitrification Enzyme Activity as an Indicator of Nitrate Movement through a Diversion Wetland
Authors: Gardner Lisa M. , White John R.
Published: April 2010

The Davis Pond freshwater diversion is intended to help restore Louisiana's coastal wetlands by reintroducing Mississippi River water to Barataria Basin. We hypothesized that the high NO3−concentration (2.0 mg NO3–N L−1) of the Mississippi River water would control the rate of denitrification in the receiving marsh given that the soils are saturated, anaerobic, and contain high C. Therefore, areas of high denitrification enzyme activity (DEA) in the marsh would represent soils exposed to river NO3−and actively involved in denitrification. Data from 88 soil samples (0–10 cm) collected throughout the marsh revealed significantly higher rates of DEA in a 715‐ha area adjacent to the diversion inflow. This area of generally high DEA contained >80% of all DEA observed while representing only 19% of the total marsh area at the low discharge rate of 39.5 m3s−1The area of high DEA coincided with the highest surface water NO3−and indicated that the marsh has a greater aerial capacity for NO3−removal than is utilized. A laboratory experiment suggested that soils loaded with external NO3−typically had higher DEA rates than soils receiving no added NO3−The DEA was strongly dependent on soil depth (92% of DEA occurred at 0–5 cm) and internal N cycling was substantial in this wetland soils. This study demonstrates the applicability of using soil DEA to map where denitrification activity is greatest, the aerial extent of soils involved in denitrification, and the general flow path of introduced nutrients in large wetlands where NO3−is the limiting factor for denitrification.
Differentiation of Soil Conditions over Low Relief Areas Using Feedback Dynamic Patterns
Authors: Zhu A-Xing , Liu Feng , Li Baolin , Pei Tao , Qin Chengzhi , Liu Gaohuan , Wang Yingjie , Chen Yaning , Ma Xingwang , Qi Feng , Zhou Chenghu
Published: April 2010

In many areas, such as plains and gently undulating terrain, easy‐to‐measure soil‐forming factors such as landform and vegetation do not co‐vary with soil conditions across space to the level that they can be effectively used in digital soil mapping. A challenging problem is how to develop a new environmental variable that co‐varies with soil spatial variation under these situations. This study examined the idea that change patterns (dynamic feedback patterns) of the land surface, such as those captured daily by remote sensing images during a short period (6–7 d) after a major rain event, can be used to differentiate soil types. To examine this idea, we selected two study areas with different climates: one in northeastern China and the other in northwestern China. Images from the Moderate Resolution Imaging Spectroradiometer (MODIS) were used to capture land surface feedback. To measure feedback dynamics, we used spectral information divergence (SID). Results of an independent‐samples t‐test showed that there was a significant difference in SID values between pixel pairs of the same soil subgroup and those of different subgroups. This indicated that areas with different soil types (subgroup level) exhibited significantly different dynamic feedback patterns, and areas within the same soil type have similar dynamic feedback patterns. It was also found that the more similar the soil types, the more similar the feedback patterns. These findings could lead to the development of a new environmental covariate that could be used to improve the accuracy of soil mapping in low‐relief areas.
Improving Hydraulic Conductivity Estimates from Minidisk Infiltrometer Measurements for Soils with Wide Pore‐Size Distributions
Authors: Dohnal Michal , Dusek Jaromir , Vogel Tomas
Published: April 2010

Disk infiltrometers are established as standard devices for measuring soil surface hydraulic properties. This study explored the validity of a semiempirical approach that is used to obtain estimates of the near‐saturated hydraulic conductivity from disk infiltrometer data. The approach was compared with two other estimation expressions. The analysis was based on three‐dimensional numerical modeling of the infiltration process, i.e., on synthetic data. The results of the validation procedure showed that the original expression performed best among the compared methods, but still failed for fine‐textured soils and the selected Cambisols. This is due to the overwhelming importance of lateral soil water movement by capillarity, which is not adequately addressed by any of the models. The study showed that improved estimates, specifically for fine‐textured soils and Cambisols and for small infiltrometer radii (minidisks), can be obtained by extending the original approach. This is achieved primarily (i) by using the modified van Genuchten parameterization of soil hydraulic functions instead of the original one, and (ii) by including a more representative set of soils in the objective function when optimizing the estimation formula.
Predicting the Spatial Variation of the Soil Organic Carbon Pool at a Regional Scale
Authors: Mishra Umakant , Lal Rattan , Liu Desheng , Van Meirvenne Marc
Published: April 2010

Estimates of soil organic C (SOC) storage and their variability at various spatial scales are essential to better understand the global C cycle, estimate C sink capacity, identify effective C sequestration strategies, and quantify the amount of SOC sequestered during a specific period of time. This study used a geographically weighted regression (GWR) approach to predict the SOC pool at a regional scale. The GWR considers varying relationships between the SOC pool and environmental variables across the study area. The range of the variogram of SOC observations was used to define a search radius in the GWR. Terrain attributes, climate data, land use data, bedrock geology, and normalized difference vegetation index data were used to predict the SOC pool for seven states in the midwestern United States. The prediction accuracy of this SOC pool map was compared with the multiple linear regression (MLR) and regression kriging (RK) approaches. Higher contrast and wider variability (1.73–39.3 kg m−2) of the SOC pool were predicted with lower global prediction errors (mean estimation error = −0.11 kg m−2, RMSE = 6.40 kg m−2) in GWR compared with the other approaches. A relative improvement of 22% over MLR and 2% over RK was observed in SOC prediction. The total SOC pool to the 0.5‐m depth was estimated to be 6.22 Pg. The results suggest that the GWR approach is a promising tool for regional‐scale SOC prediction.
Hydraulic Conductivity Function from Water Flow Similarity in Idealized‐ and Natural‐Structure Pores
Authors: Arya Lalit M. , Heitman J.L.
Published: April 2010

Our objective was to develop and evaluate a simple, primarily physically based hydraulic conductivity model for natural‐structure soils. The proposed model of the hydraulic conductivity function, K(θ), is based on particle‐size distribution (PSD), flow in idealized capillary tubes of uniform diameter, and measured saturated hydraulic conductivity (Ks). We assume that hydraulic conductivity at a given saturation is actually saturated conductivity of pores that remain filled at that saturation, i.e., insignificant contribution from unfilled pores. The PSD data are used to generate pore‐size distribution using the Arya–Paris model, based on soil water characteristics. Pores are first treated as idealized, and flow for each domain is calculated using the Hagen–Poiseuille flow equation. We further assume that the ratio of flow in any pore domain to total flow at saturation for idealized pores applies equally to natural‐structure pores. Using this equality, the total flow at saturation, obtained from measured Ks, is distributed among the natural pore domains. This approach is advantageous in that flow parameters remain constant for all soils. Using the model, we calculated K(θ) for 29 soils with a wide range of physical properties. Agreement between predicted and experimental data was excellent to good for 21 soils (r2 > 0.9 for 14 soils, >0.8 for 7 soils). Poorer agreement in the remaining soils was attributed to uncertainty in input and experimental K(θ) data. A 1:1 comparison of log‐transformed predicted and experimental data for the 29 soils (719 data pairs) showed significant scatter(r2 = 0.735, RMSE = 1.04), which is consistent with similar comparisons in the literature.
Using a New Criterion to Identify Sites for Mean Soil Water Storage Evaluation
Authors: Hu Wei , Shao Mingan , Reichardt Klaus
Published: April 2010

Establishing a few sites in which measurements of soil water storage (SWS) are time stable significantly reduces the efforts involved in determining average values of SWS. This study aimed to apply a new criterion—the mean absolute bias error (MABE)—to identify temporally stable sites for mean SWS evaluation. The performance of MABE was compared with that of the commonly used criterion, the standard deviation of relative difference (SDRD). From October 2004 to October 2008, SWS of four soil layers (0–1.0, 1.0–2.0, 2.0–3.0, and 3.0–4.0 m) was measured, using a neutron probe, at 28 sites on a hillslope of the Loess Plateau, China. A total of 37 SWS data sets taken over time were divided into two subsets, the first consisting of 22 dates collected during the calibration period from October 2004 to September 2006, and the second with 15 dates collected during the validation period from October 2006 to October 2008. The results showed that if a critical value of 5% for MABE was defined, more than half the sites were temporally stable for both periods, and the number of temporally stable sites generally increased with soil depth. Compared with SDRD, MABE was more suitable for the identification of time‐stable sites for mean SWS prediction. Since the absolute prediction error of drier sites is more sensitive to changes in relative difference in terms of mean SWS prediction, the sites of wet sectors should be preferable for mean SWS prediction for the same changes in relative difference.
Upscaling of Dynamic Soil Organic Carbon Pools in a North‐Central Florida Watershed
Authors: Vasques Gustavo M. , Grunwald Sabine , Sickman James O. , Comerford Nicholas B.
Published: April 2010

Regional‐scale assessment of soil C pools is essential to provide information for C cycling models, land management, and policy decisions, and elucidate the relative contribution of different C pools to total C (TC). We estimated TC and four soil C fractions, namely recalcitrant C (RC), hydrolyzable C (HC), hot‐water‐soluble C (SC), and mineralizable C (MC), at 0 to 30 cm across a 3585‐km2 mixed‐use watershed in north‐central Florida. We used lognormal block kriging (BK) and regression block kriging (RK) to upscale soil C using 102 training samples and compared the models using 39 validation samples. Regression kriging produced the most accurate models for TC and RC, whereas the labile C fractions (HC, SC, and MC) were best modeled by BK. Maps produced by BK showed similar spatial patterns due to the strong correlation between the labile C fractions and the similarity of their spatial dependence structure. Estimates of TC and RC were similar due to their high correlation and the similarity of their global trend models. Total soil C amounted to 27.40 Tg across the watershed, indicating the potential of these soils to store C. Recalcitrant C totaled 22.49 Tg (82% of TC), suggesting that a large amount of TC could be potentially stored for centuries to millennia. Our estimates of soil C and fractions within a mixed‐use watershed in Florida highlight the importance of appropriately characterizing the inherent spatial dependence structure of soil C, as well as relevant regional environmental patterns (e.g., hydrology), to better explain the variability of soil C.